1457c8996SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 21da177e4SLinus Torvalds /* 31da177e4SLinus Torvalds * Generic hugetlb support. 46d49e352SNadia Yvette Chambers * (C) Nadia Yvette Chambers, April 2004 51da177e4SLinus Torvalds */ 61da177e4SLinus Torvalds #include <linux/list.h> 71da177e4SLinus Torvalds #include <linux/init.h> 81da177e4SLinus Torvalds #include <linux/mm.h> 9e1759c21SAlexey Dobriyan #include <linux/seq_file.h> 101da177e4SLinus Torvalds #include <linux/sysctl.h> 111da177e4SLinus Torvalds #include <linux/highmem.h> 12cddb8a5cSAndrea Arcangeli #include <linux/mmu_notifier.h> 131da177e4SLinus Torvalds #include <linux/nodemask.h> 1463551ae0SDavid Gibson #include <linux/pagemap.h> 155da7ca86SChristoph Lameter #include <linux/mempolicy.h> 163b32123dSGideon Israel Dsouza #include <linux/compiler.h> 17aea47ff3SChristoph Lameter #include <linux/cpuset.h> 183935baa9SDavid Gibson #include <linux/mutex.h> 1997ad1087SMike Rapoport #include <linux/memblock.h> 20a3437870SNishanth Aravamudan #include <linux/sysfs.h> 215a0e3ad6STejun Heo #include <linux/slab.h> 22bbe88753SJoonsoo Kim #include <linux/sched/mm.h> 2363489f8eSMike Kravetz #include <linux/mmdebug.h> 24174cd4b1SIngo Molnar #include <linux/sched/signal.h> 250fe6e20bSNaoya Horiguchi #include <linux/rmap.h> 26c6247f72SMatthew Wilcox #include <linux/string_helpers.h> 27fd6a03edSNaoya Horiguchi #include <linux/swap.h> 28fd6a03edSNaoya Horiguchi #include <linux/swapops.h> 298382d914SDavidlohr Bueso #include <linux/jhash.h> 3098fa15f3SAnshuman Khandual #include <linux/numa.h> 31c77c0a8aSWaiman Long #include <linux/llist.h> 32cf11e85fSRoman Gushchin #include <linux/cma.h> 338cc5fcbbSMina Almasry #include <linux/migrate.h> 34d6606683SLinus Torvalds 3563551ae0SDavid Gibson #include <asm/page.h> 36ca15ca40SMike Rapoport #include <asm/pgalloc.h> 3724669e58SAneesh Kumar K.V #include <asm/tlb.h> 3863551ae0SDavid Gibson 3924669e58SAneesh Kumar K.V #include <linux/io.h> 4063551ae0SDavid Gibson #include <linux/hugetlb.h> 419dd540e2SAneesh Kumar K.V #include <linux/hugetlb_cgroup.h> 429a305230SLee Schermerhorn #include <linux/node.h> 43ab5ac90aSMichal Hocko #include <linux/page_owner.h> 447835e98bSNick Piggin #include "internal.h" 45f41f2ed4SMuchun Song #include "hugetlb_vmemmap.h" 461da177e4SLinus Torvalds 47c3f38a38SAneesh Kumar K.V int hugetlb_max_hstate __read_mostly; 48e5ff2159SAndi Kleen unsigned int default_hstate_idx; 49e5ff2159SAndi Kleen struct hstate hstates[HUGE_MAX_HSTATE]; 50cf11e85fSRoman Gushchin 51dbda8feaSBarry Song #ifdef CONFIG_CMA 52cf11e85fSRoman Gushchin static struct cma *hugetlb_cma[MAX_NUMNODES]; 53a01f4390SMike Kravetz static bool hugetlb_cma_page(struct page *page, unsigned int order) 54a01f4390SMike Kravetz { 55a01f4390SMike Kravetz return cma_pages_valid(hugetlb_cma[page_to_nid(page)], page, 56a01f4390SMike Kravetz 1 << order); 57a01f4390SMike Kravetz } 58a01f4390SMike Kravetz #else 59a01f4390SMike Kravetz static bool hugetlb_cma_page(struct page *page, unsigned int order) 60a01f4390SMike Kravetz { 61a01f4390SMike Kravetz return false; 62a01f4390SMike Kravetz } 63dbda8feaSBarry Song #endif 64dbda8feaSBarry Song static unsigned long hugetlb_cma_size __initdata; 65cf11e85fSRoman Gushchin 66641844f5SNaoya Horiguchi /* 67641844f5SNaoya Horiguchi * Minimum page order among possible hugepage sizes, set to a proper value 68641844f5SNaoya Horiguchi * at boot time. 69641844f5SNaoya Horiguchi */ 70641844f5SNaoya Horiguchi static unsigned int minimum_order __read_mostly = UINT_MAX; 71e5ff2159SAndi Kleen 7253ba51d2SJon Tollefson __initdata LIST_HEAD(huge_boot_pages); 7353ba51d2SJon Tollefson 74e5ff2159SAndi Kleen /* for command line parsing */ 75e5ff2159SAndi Kleen static struct hstate * __initdata parsed_hstate; 76e5ff2159SAndi Kleen static unsigned long __initdata default_hstate_max_huge_pages; 779fee021dSVaishali Thakkar static bool __initdata parsed_valid_hugepagesz = true; 78282f4214SMike Kravetz static bool __initdata parsed_default_hugepagesz; 79e5ff2159SAndi Kleen 803935baa9SDavid Gibson /* 8131caf665SNaoya Horiguchi * Protects updates to hugepage_freelists, hugepage_activelist, nr_huge_pages, 8231caf665SNaoya Horiguchi * free_huge_pages, and surplus_huge_pages. 833935baa9SDavid Gibson */ 84c3f38a38SAneesh Kumar K.V DEFINE_SPINLOCK(hugetlb_lock); 850bd0f9fbSEric Paris 868382d914SDavidlohr Bueso /* 878382d914SDavidlohr Bueso * Serializes faults on the same logical page. This is used to 888382d914SDavidlohr Bueso * prevent spurious OOMs when the hugepage pool is fully utilized. 898382d914SDavidlohr Bueso */ 908382d914SDavidlohr Bueso static int num_fault_mutexes; 91c672c7f2SMike Kravetz struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp; 928382d914SDavidlohr Bueso 937ca02d0aSMike Kravetz /* Forward declaration */ 947ca02d0aSMike Kravetz static int hugetlb_acct_memory(struct hstate *h, long delta); 957ca02d0aSMike Kravetz 961d88433bSMiaohe Lin static inline bool subpool_is_free(struct hugepage_subpool *spool) 971d88433bSMiaohe Lin { 981d88433bSMiaohe Lin if (spool->count) 991d88433bSMiaohe Lin return false; 1001d88433bSMiaohe Lin if (spool->max_hpages != -1) 1011d88433bSMiaohe Lin return spool->used_hpages == 0; 1021d88433bSMiaohe Lin if (spool->min_hpages != -1) 1031d88433bSMiaohe Lin return spool->rsv_hpages == spool->min_hpages; 1041d88433bSMiaohe Lin 1051d88433bSMiaohe Lin return true; 1061d88433bSMiaohe Lin } 1071d88433bSMiaohe Lin 108db71ef79SMike Kravetz static inline void unlock_or_release_subpool(struct hugepage_subpool *spool, 109db71ef79SMike Kravetz unsigned long irq_flags) 11090481622SDavid Gibson { 111db71ef79SMike Kravetz spin_unlock_irqrestore(&spool->lock, irq_flags); 11290481622SDavid Gibson 11390481622SDavid Gibson /* If no pages are used, and no other handles to the subpool 1147c8de358SEthon Paul * remain, give up any reservations based on minimum size and 1157ca02d0aSMike Kravetz * free the subpool */ 1161d88433bSMiaohe Lin if (subpool_is_free(spool)) { 1177ca02d0aSMike Kravetz if (spool->min_hpages != -1) 1187ca02d0aSMike Kravetz hugetlb_acct_memory(spool->hstate, 1197ca02d0aSMike Kravetz -spool->min_hpages); 12090481622SDavid Gibson kfree(spool); 12190481622SDavid Gibson } 1227ca02d0aSMike Kravetz } 12390481622SDavid Gibson 1247ca02d0aSMike Kravetz struct hugepage_subpool *hugepage_new_subpool(struct hstate *h, long max_hpages, 1257ca02d0aSMike Kravetz long min_hpages) 12690481622SDavid Gibson { 12790481622SDavid Gibson struct hugepage_subpool *spool; 12890481622SDavid Gibson 129c6a91820SMike Kravetz spool = kzalloc(sizeof(*spool), GFP_KERNEL); 13090481622SDavid Gibson if (!spool) 13190481622SDavid Gibson return NULL; 13290481622SDavid Gibson 13390481622SDavid Gibson spin_lock_init(&spool->lock); 13490481622SDavid Gibson spool->count = 1; 1357ca02d0aSMike Kravetz spool->max_hpages = max_hpages; 1367ca02d0aSMike Kravetz spool->hstate = h; 1377ca02d0aSMike Kravetz spool->min_hpages = min_hpages; 1387ca02d0aSMike Kravetz 1397ca02d0aSMike Kravetz if (min_hpages != -1 && hugetlb_acct_memory(h, min_hpages)) { 1407ca02d0aSMike Kravetz kfree(spool); 1417ca02d0aSMike Kravetz return NULL; 1427ca02d0aSMike Kravetz } 1437ca02d0aSMike Kravetz spool->rsv_hpages = min_hpages; 14490481622SDavid Gibson 14590481622SDavid Gibson return spool; 14690481622SDavid Gibson } 14790481622SDavid Gibson 14890481622SDavid Gibson void hugepage_put_subpool(struct hugepage_subpool *spool) 14990481622SDavid Gibson { 150db71ef79SMike Kravetz unsigned long flags; 151db71ef79SMike Kravetz 152db71ef79SMike Kravetz spin_lock_irqsave(&spool->lock, flags); 15390481622SDavid Gibson BUG_ON(!spool->count); 15490481622SDavid Gibson spool->count--; 155db71ef79SMike Kravetz unlock_or_release_subpool(spool, flags); 15690481622SDavid Gibson } 15790481622SDavid Gibson 1581c5ecae3SMike Kravetz /* 1591c5ecae3SMike Kravetz * Subpool accounting for allocating and reserving pages. 1601c5ecae3SMike Kravetz * Return -ENOMEM if there are not enough resources to satisfy the 1619e7ee400SRandy Dunlap * request. Otherwise, return the number of pages by which the 1621c5ecae3SMike Kravetz * global pools must be adjusted (upward). The returned value may 1631c5ecae3SMike Kravetz * only be different than the passed value (delta) in the case where 1647c8de358SEthon Paul * a subpool minimum size must be maintained. 1651c5ecae3SMike Kravetz */ 1661c5ecae3SMike Kravetz static long hugepage_subpool_get_pages(struct hugepage_subpool *spool, 16790481622SDavid Gibson long delta) 16890481622SDavid Gibson { 1691c5ecae3SMike Kravetz long ret = delta; 17090481622SDavid Gibson 17190481622SDavid Gibson if (!spool) 1721c5ecae3SMike Kravetz return ret; 17390481622SDavid Gibson 174db71ef79SMike Kravetz spin_lock_irq(&spool->lock); 17590481622SDavid Gibson 1761c5ecae3SMike Kravetz if (spool->max_hpages != -1) { /* maximum size accounting */ 1771c5ecae3SMike Kravetz if ((spool->used_hpages + delta) <= spool->max_hpages) 1781c5ecae3SMike Kravetz spool->used_hpages += delta; 1791c5ecae3SMike Kravetz else { 1801c5ecae3SMike Kravetz ret = -ENOMEM; 1811c5ecae3SMike Kravetz goto unlock_ret; 1821c5ecae3SMike Kravetz } 1831c5ecae3SMike Kravetz } 1841c5ecae3SMike Kravetz 18509a95e29SMike Kravetz /* minimum size accounting */ 18609a95e29SMike Kravetz if (spool->min_hpages != -1 && spool->rsv_hpages) { 1871c5ecae3SMike Kravetz if (delta > spool->rsv_hpages) { 1881c5ecae3SMike Kravetz /* 1891c5ecae3SMike Kravetz * Asking for more reserves than those already taken on 1901c5ecae3SMike Kravetz * behalf of subpool. Return difference. 1911c5ecae3SMike Kravetz */ 1921c5ecae3SMike Kravetz ret = delta - spool->rsv_hpages; 1931c5ecae3SMike Kravetz spool->rsv_hpages = 0; 1941c5ecae3SMike Kravetz } else { 1951c5ecae3SMike Kravetz ret = 0; /* reserves already accounted for */ 1961c5ecae3SMike Kravetz spool->rsv_hpages -= delta; 1971c5ecae3SMike Kravetz } 1981c5ecae3SMike Kravetz } 1991c5ecae3SMike Kravetz 2001c5ecae3SMike Kravetz unlock_ret: 201db71ef79SMike Kravetz spin_unlock_irq(&spool->lock); 20290481622SDavid Gibson return ret; 20390481622SDavid Gibson } 20490481622SDavid Gibson 2051c5ecae3SMike Kravetz /* 2061c5ecae3SMike Kravetz * Subpool accounting for freeing and unreserving pages. 2071c5ecae3SMike Kravetz * Return the number of global page reservations that must be dropped. 2081c5ecae3SMike Kravetz * The return value may only be different than the passed value (delta) 2091c5ecae3SMike Kravetz * in the case where a subpool minimum size must be maintained. 2101c5ecae3SMike Kravetz */ 2111c5ecae3SMike Kravetz static long hugepage_subpool_put_pages(struct hugepage_subpool *spool, 21290481622SDavid Gibson long delta) 21390481622SDavid Gibson { 2141c5ecae3SMike Kravetz long ret = delta; 215db71ef79SMike Kravetz unsigned long flags; 2161c5ecae3SMike Kravetz 21790481622SDavid Gibson if (!spool) 2181c5ecae3SMike Kravetz return delta; 21990481622SDavid Gibson 220db71ef79SMike Kravetz spin_lock_irqsave(&spool->lock, flags); 2211c5ecae3SMike Kravetz 2221c5ecae3SMike Kravetz if (spool->max_hpages != -1) /* maximum size accounting */ 22390481622SDavid Gibson spool->used_hpages -= delta; 2241c5ecae3SMike Kravetz 22509a95e29SMike Kravetz /* minimum size accounting */ 22609a95e29SMike Kravetz if (spool->min_hpages != -1 && spool->used_hpages < spool->min_hpages) { 2271c5ecae3SMike Kravetz if (spool->rsv_hpages + delta <= spool->min_hpages) 2281c5ecae3SMike Kravetz ret = 0; 2291c5ecae3SMike Kravetz else 2301c5ecae3SMike Kravetz ret = spool->rsv_hpages + delta - spool->min_hpages; 2311c5ecae3SMike Kravetz 2321c5ecae3SMike Kravetz spool->rsv_hpages += delta; 2331c5ecae3SMike Kravetz if (spool->rsv_hpages > spool->min_hpages) 2341c5ecae3SMike Kravetz spool->rsv_hpages = spool->min_hpages; 2351c5ecae3SMike Kravetz } 2361c5ecae3SMike Kravetz 2371c5ecae3SMike Kravetz /* 2381c5ecae3SMike Kravetz * If hugetlbfs_put_super couldn't free spool due to an outstanding 2391c5ecae3SMike Kravetz * quota reference, free it now. 2401c5ecae3SMike Kravetz */ 241db71ef79SMike Kravetz unlock_or_release_subpool(spool, flags); 2421c5ecae3SMike Kravetz 2431c5ecae3SMike Kravetz return ret; 24490481622SDavid Gibson } 24590481622SDavid Gibson 24690481622SDavid Gibson static inline struct hugepage_subpool *subpool_inode(struct inode *inode) 24790481622SDavid Gibson { 24890481622SDavid Gibson return HUGETLBFS_SB(inode->i_sb)->spool; 24990481622SDavid Gibson } 25090481622SDavid Gibson 25190481622SDavid Gibson static inline struct hugepage_subpool *subpool_vma(struct vm_area_struct *vma) 25290481622SDavid Gibson { 253496ad9aaSAl Viro return subpool_inode(file_inode(vma->vm_file)); 25490481622SDavid Gibson } 25590481622SDavid Gibson 2560db9d74eSMina Almasry /* Helper that removes a struct file_region from the resv_map cache and returns 2570db9d74eSMina Almasry * it for use. 2580db9d74eSMina Almasry */ 2590db9d74eSMina Almasry static struct file_region * 2600db9d74eSMina Almasry get_file_region_entry_from_cache(struct resv_map *resv, long from, long to) 2610db9d74eSMina Almasry { 2620db9d74eSMina Almasry struct file_region *nrg = NULL; 2630db9d74eSMina Almasry 2640db9d74eSMina Almasry VM_BUG_ON(resv->region_cache_count <= 0); 2650db9d74eSMina Almasry 2660db9d74eSMina Almasry resv->region_cache_count--; 2670db9d74eSMina Almasry nrg = list_first_entry(&resv->region_cache, struct file_region, link); 2680db9d74eSMina Almasry list_del(&nrg->link); 2690db9d74eSMina Almasry 2700db9d74eSMina Almasry nrg->from = from; 2710db9d74eSMina Almasry nrg->to = to; 2720db9d74eSMina Almasry 2730db9d74eSMina Almasry return nrg; 2740db9d74eSMina Almasry } 2750db9d74eSMina Almasry 276075a61d0SMina Almasry static void copy_hugetlb_cgroup_uncharge_info(struct file_region *nrg, 277075a61d0SMina Almasry struct file_region *rg) 278075a61d0SMina Almasry { 279075a61d0SMina Almasry #ifdef CONFIG_CGROUP_HUGETLB 280075a61d0SMina Almasry nrg->reservation_counter = rg->reservation_counter; 281075a61d0SMina Almasry nrg->css = rg->css; 282075a61d0SMina Almasry if (rg->css) 283075a61d0SMina Almasry css_get(rg->css); 284075a61d0SMina Almasry #endif 285075a61d0SMina Almasry } 286075a61d0SMina Almasry 287075a61d0SMina Almasry /* Helper that records hugetlb_cgroup uncharge info. */ 288075a61d0SMina Almasry static void record_hugetlb_cgroup_uncharge_info(struct hugetlb_cgroup *h_cg, 289075a61d0SMina Almasry struct hstate *h, 290075a61d0SMina Almasry struct resv_map *resv, 291075a61d0SMina Almasry struct file_region *nrg) 292075a61d0SMina Almasry { 293075a61d0SMina Almasry #ifdef CONFIG_CGROUP_HUGETLB 294075a61d0SMina Almasry if (h_cg) { 295075a61d0SMina Almasry nrg->reservation_counter = 296075a61d0SMina Almasry &h_cg->rsvd_hugepage[hstate_index(h)]; 297075a61d0SMina Almasry nrg->css = &h_cg->css; 298d85aecf2SMiaohe Lin /* 299d85aecf2SMiaohe Lin * The caller will hold exactly one h_cg->css reference for the 300d85aecf2SMiaohe Lin * whole contiguous reservation region. But this area might be 301d85aecf2SMiaohe Lin * scattered when there are already some file_regions reside in 302d85aecf2SMiaohe Lin * it. As a result, many file_regions may share only one css 303d85aecf2SMiaohe Lin * reference. In order to ensure that one file_region must hold 304d85aecf2SMiaohe Lin * exactly one h_cg->css reference, we should do css_get for 305d85aecf2SMiaohe Lin * each file_region and leave the reference held by caller 306d85aecf2SMiaohe Lin * untouched. 307d85aecf2SMiaohe Lin */ 308d85aecf2SMiaohe Lin css_get(&h_cg->css); 309075a61d0SMina Almasry if (!resv->pages_per_hpage) 310075a61d0SMina Almasry resv->pages_per_hpage = pages_per_huge_page(h); 311075a61d0SMina Almasry /* pages_per_hpage should be the same for all entries in 312075a61d0SMina Almasry * a resv_map. 313075a61d0SMina Almasry */ 314075a61d0SMina Almasry VM_BUG_ON(resv->pages_per_hpage != pages_per_huge_page(h)); 315075a61d0SMina Almasry } else { 316075a61d0SMina Almasry nrg->reservation_counter = NULL; 317075a61d0SMina Almasry nrg->css = NULL; 318075a61d0SMina Almasry } 319075a61d0SMina Almasry #endif 320075a61d0SMina Almasry } 321075a61d0SMina Almasry 322d85aecf2SMiaohe Lin static void put_uncharge_info(struct file_region *rg) 323d85aecf2SMiaohe Lin { 324d85aecf2SMiaohe Lin #ifdef CONFIG_CGROUP_HUGETLB 325d85aecf2SMiaohe Lin if (rg->css) 326d85aecf2SMiaohe Lin css_put(rg->css); 327d85aecf2SMiaohe Lin #endif 328d85aecf2SMiaohe Lin } 329d85aecf2SMiaohe Lin 330a9b3f867SMina Almasry static bool has_same_uncharge_info(struct file_region *rg, 331a9b3f867SMina Almasry struct file_region *org) 332a9b3f867SMina Almasry { 333a9b3f867SMina Almasry #ifdef CONFIG_CGROUP_HUGETLB 334a9b3f867SMina Almasry return rg && org && 335a9b3f867SMina Almasry rg->reservation_counter == org->reservation_counter && 336a9b3f867SMina Almasry rg->css == org->css; 337a9b3f867SMina Almasry 338a9b3f867SMina Almasry #else 339a9b3f867SMina Almasry return true; 340a9b3f867SMina Almasry #endif 341a9b3f867SMina Almasry } 342a9b3f867SMina Almasry 343a9b3f867SMina Almasry static void coalesce_file_region(struct resv_map *resv, struct file_region *rg) 344a9b3f867SMina Almasry { 345a9b3f867SMina Almasry struct file_region *nrg = NULL, *prg = NULL; 346a9b3f867SMina Almasry 347a9b3f867SMina Almasry prg = list_prev_entry(rg, link); 348a9b3f867SMina Almasry if (&prg->link != &resv->regions && prg->to == rg->from && 349a9b3f867SMina Almasry has_same_uncharge_info(prg, rg)) { 350a9b3f867SMina Almasry prg->to = rg->to; 351a9b3f867SMina Almasry 352a9b3f867SMina Almasry list_del(&rg->link); 353d85aecf2SMiaohe Lin put_uncharge_info(rg); 354a9b3f867SMina Almasry kfree(rg); 355a9b3f867SMina Almasry 3567db5e7b6SWei Yang rg = prg; 357a9b3f867SMina Almasry } 358a9b3f867SMina Almasry 359a9b3f867SMina Almasry nrg = list_next_entry(rg, link); 360a9b3f867SMina Almasry if (&nrg->link != &resv->regions && nrg->from == rg->to && 361a9b3f867SMina Almasry has_same_uncharge_info(nrg, rg)) { 362a9b3f867SMina Almasry nrg->from = rg->from; 363a9b3f867SMina Almasry 364a9b3f867SMina Almasry list_del(&rg->link); 365d85aecf2SMiaohe Lin put_uncharge_info(rg); 366a9b3f867SMina Almasry kfree(rg); 367a9b3f867SMina Almasry } 368a9b3f867SMina Almasry } 369a9b3f867SMina Almasry 3702103cf9cSPeter Xu static inline long 3712103cf9cSPeter Xu hugetlb_resv_map_add(struct resv_map *map, struct file_region *rg, long from, 3722103cf9cSPeter Xu long to, struct hstate *h, struct hugetlb_cgroup *cg, 3732103cf9cSPeter Xu long *regions_needed) 3742103cf9cSPeter Xu { 3752103cf9cSPeter Xu struct file_region *nrg; 3762103cf9cSPeter Xu 3772103cf9cSPeter Xu if (!regions_needed) { 3782103cf9cSPeter Xu nrg = get_file_region_entry_from_cache(map, from, to); 3792103cf9cSPeter Xu record_hugetlb_cgroup_uncharge_info(cg, h, map, nrg); 3802103cf9cSPeter Xu list_add(&nrg->link, rg->link.prev); 3812103cf9cSPeter Xu coalesce_file_region(map, nrg); 3822103cf9cSPeter Xu } else 3832103cf9cSPeter Xu *regions_needed += 1; 3842103cf9cSPeter Xu 3852103cf9cSPeter Xu return to - from; 3862103cf9cSPeter Xu } 3872103cf9cSPeter Xu 388972a3da3SWei Yang /* 389972a3da3SWei Yang * Must be called with resv->lock held. 390972a3da3SWei Yang * 391972a3da3SWei Yang * Calling this with regions_needed != NULL will count the number of pages 392972a3da3SWei Yang * to be added but will not modify the linked list. And regions_needed will 393972a3da3SWei Yang * indicate the number of file_regions needed in the cache to carry out to add 394972a3da3SWei Yang * the regions for this range. 395d75c6af9SMina Almasry */ 396d75c6af9SMina Almasry static long add_reservation_in_range(struct resv_map *resv, long f, long t, 397075a61d0SMina Almasry struct hugetlb_cgroup *h_cg, 398972a3da3SWei Yang struct hstate *h, long *regions_needed) 399d75c6af9SMina Almasry { 4000db9d74eSMina Almasry long add = 0; 401d75c6af9SMina Almasry struct list_head *head = &resv->regions; 4020db9d74eSMina Almasry long last_accounted_offset = f; 4032103cf9cSPeter Xu struct file_region *rg = NULL, *trg = NULL; 404d75c6af9SMina Almasry 4050db9d74eSMina Almasry if (regions_needed) 4060db9d74eSMina Almasry *regions_needed = 0; 407d75c6af9SMina Almasry 4080db9d74eSMina Almasry /* In this loop, we essentially handle an entry for the range 4090db9d74eSMina Almasry * [last_accounted_offset, rg->from), at every iteration, with some 4100db9d74eSMina Almasry * bounds checking. 4110db9d74eSMina Almasry */ 4120db9d74eSMina Almasry list_for_each_entry_safe(rg, trg, head, link) { 4130db9d74eSMina Almasry /* Skip irrelevant regions that start before our range. */ 4140db9d74eSMina Almasry if (rg->from < f) { 4150db9d74eSMina Almasry /* If this region ends after the last accounted offset, 4160db9d74eSMina Almasry * then we need to update last_accounted_offset. 4170db9d74eSMina Almasry */ 4180db9d74eSMina Almasry if (rg->to > last_accounted_offset) 4190db9d74eSMina Almasry last_accounted_offset = rg->to; 4200db9d74eSMina Almasry continue; 4210db9d74eSMina Almasry } 422d75c6af9SMina Almasry 4230db9d74eSMina Almasry /* When we find a region that starts beyond our range, we've 4240db9d74eSMina Almasry * finished. 4250db9d74eSMina Almasry */ 426ca7e0457SPeter Xu if (rg->from >= t) 427d75c6af9SMina Almasry break; 428d75c6af9SMina Almasry 4290db9d74eSMina Almasry /* Add an entry for last_accounted_offset -> rg->from, and 4300db9d74eSMina Almasry * update last_accounted_offset. 431d75c6af9SMina Almasry */ 4322103cf9cSPeter Xu if (rg->from > last_accounted_offset) 4332103cf9cSPeter Xu add += hugetlb_resv_map_add(resv, rg, 4342103cf9cSPeter Xu last_accounted_offset, 4352103cf9cSPeter Xu rg->from, h, h_cg, 4362103cf9cSPeter Xu regions_needed); 437d75c6af9SMina Almasry 4380db9d74eSMina Almasry last_accounted_offset = rg->to; 4390db9d74eSMina Almasry } 4400db9d74eSMina Almasry 4410db9d74eSMina Almasry /* Handle the case where our range extends beyond 4420db9d74eSMina Almasry * last_accounted_offset. 4430db9d74eSMina Almasry */ 4442103cf9cSPeter Xu if (last_accounted_offset < t) 4452103cf9cSPeter Xu add += hugetlb_resv_map_add(resv, rg, last_accounted_offset, 4462103cf9cSPeter Xu t, h, h_cg, regions_needed); 4470db9d74eSMina Almasry 4480db9d74eSMina Almasry VM_BUG_ON(add < 0); 4490db9d74eSMina Almasry return add; 4500db9d74eSMina Almasry } 4510db9d74eSMina Almasry 4520db9d74eSMina Almasry /* Must be called with resv->lock acquired. Will drop lock to allocate entries. 4530db9d74eSMina Almasry */ 4540db9d74eSMina Almasry static int allocate_file_region_entries(struct resv_map *resv, 4550db9d74eSMina Almasry int regions_needed) 4560db9d74eSMina Almasry __must_hold(&resv->lock) 4570db9d74eSMina Almasry { 4580db9d74eSMina Almasry struct list_head allocated_regions; 4590db9d74eSMina Almasry int to_allocate = 0, i = 0; 4600db9d74eSMina Almasry struct file_region *trg = NULL, *rg = NULL; 4610db9d74eSMina Almasry 4620db9d74eSMina Almasry VM_BUG_ON(regions_needed < 0); 4630db9d74eSMina Almasry 4640db9d74eSMina Almasry INIT_LIST_HEAD(&allocated_regions); 4650db9d74eSMina Almasry 4660db9d74eSMina Almasry /* 4670db9d74eSMina Almasry * Check for sufficient descriptors in the cache to accommodate 4680db9d74eSMina Almasry * the number of in progress add operations plus regions_needed. 4690db9d74eSMina Almasry * 4700db9d74eSMina Almasry * This is a while loop because when we drop the lock, some other call 4710db9d74eSMina Almasry * to region_add or region_del may have consumed some region_entries, 4720db9d74eSMina Almasry * so we keep looping here until we finally have enough entries for 4730db9d74eSMina Almasry * (adds_in_progress + regions_needed). 4740db9d74eSMina Almasry */ 4750db9d74eSMina Almasry while (resv->region_cache_count < 4760db9d74eSMina Almasry (resv->adds_in_progress + regions_needed)) { 4770db9d74eSMina Almasry to_allocate = resv->adds_in_progress + regions_needed - 4780db9d74eSMina Almasry resv->region_cache_count; 4790db9d74eSMina Almasry 4800db9d74eSMina Almasry /* At this point, we should have enough entries in the cache 481f0953a1bSIngo Molnar * for all the existing adds_in_progress. We should only be 4820db9d74eSMina Almasry * needing to allocate for regions_needed. 4830db9d74eSMina Almasry */ 4840db9d74eSMina Almasry VM_BUG_ON(resv->region_cache_count < resv->adds_in_progress); 4850db9d74eSMina Almasry 4860db9d74eSMina Almasry spin_unlock(&resv->lock); 4870db9d74eSMina Almasry for (i = 0; i < to_allocate; i++) { 4880db9d74eSMina Almasry trg = kmalloc(sizeof(*trg), GFP_KERNEL); 4890db9d74eSMina Almasry if (!trg) 4900db9d74eSMina Almasry goto out_of_memory; 4910db9d74eSMina Almasry list_add(&trg->link, &allocated_regions); 4920db9d74eSMina Almasry } 4930db9d74eSMina Almasry 4940db9d74eSMina Almasry spin_lock(&resv->lock); 4950db9d74eSMina Almasry 496d3ec7b6eSWei Yang list_splice(&allocated_regions, &resv->region_cache); 497d3ec7b6eSWei Yang resv->region_cache_count += to_allocate; 4980db9d74eSMina Almasry } 4990db9d74eSMina Almasry 5000db9d74eSMina Almasry return 0; 5010db9d74eSMina Almasry 5020db9d74eSMina Almasry out_of_memory: 5030db9d74eSMina Almasry list_for_each_entry_safe(rg, trg, &allocated_regions, link) { 504d75c6af9SMina Almasry list_del(&rg->link); 505d75c6af9SMina Almasry kfree(rg); 506d75c6af9SMina Almasry } 5070db9d74eSMina Almasry return -ENOMEM; 508d75c6af9SMina Almasry } 509d75c6af9SMina Almasry 5101dd308a7SMike Kravetz /* 5111dd308a7SMike Kravetz * Add the huge page range represented by [f, t) to the reserve 5120db9d74eSMina Almasry * map. Regions will be taken from the cache to fill in this range. 5130db9d74eSMina Almasry * Sufficient regions should exist in the cache due to the previous 5140db9d74eSMina Almasry * call to region_chg with the same range, but in some cases the cache will not 5150db9d74eSMina Almasry * have sufficient entries due to races with other code doing region_add or 5160db9d74eSMina Almasry * region_del. The extra needed entries will be allocated. 517cf3ad20bSMike Kravetz * 5180db9d74eSMina Almasry * regions_needed is the out value provided by a previous call to region_chg. 5190db9d74eSMina Almasry * 5200db9d74eSMina Almasry * Return the number of new huge pages added to the map. This number is greater 5210db9d74eSMina Almasry * than or equal to zero. If file_region entries needed to be allocated for 5227c8de358SEthon Paul * this operation and we were not able to allocate, it returns -ENOMEM. 5230db9d74eSMina Almasry * region_add of regions of length 1 never allocate file_regions and cannot 5240db9d74eSMina Almasry * fail; region_chg will always allocate at least 1 entry and a region_add for 5250db9d74eSMina Almasry * 1 page will only require at most 1 entry. 5261dd308a7SMike Kravetz */ 5270db9d74eSMina Almasry static long region_add(struct resv_map *resv, long f, long t, 528075a61d0SMina Almasry long in_regions_needed, struct hstate *h, 529075a61d0SMina Almasry struct hugetlb_cgroup *h_cg) 53096822904SAndy Whitcroft { 5310db9d74eSMina Almasry long add = 0, actual_regions_needed = 0; 53296822904SAndy Whitcroft 5337b24d861SDavidlohr Bueso spin_lock(&resv->lock); 5340db9d74eSMina Almasry retry: 5350db9d74eSMina Almasry 5360db9d74eSMina Almasry /* Count how many regions are actually needed to execute this add. */ 537972a3da3SWei Yang add_reservation_in_range(resv, f, t, NULL, NULL, 538972a3da3SWei Yang &actual_regions_needed); 53996822904SAndy Whitcroft 5405e911373SMike Kravetz /* 5410db9d74eSMina Almasry * Check for sufficient descriptors in the cache to accommodate 5420db9d74eSMina Almasry * this add operation. Note that actual_regions_needed may be greater 5430db9d74eSMina Almasry * than in_regions_needed, as the resv_map may have been modified since 5440db9d74eSMina Almasry * the region_chg call. In this case, we need to make sure that we 5450db9d74eSMina Almasry * allocate extra entries, such that we have enough for all the 5460db9d74eSMina Almasry * existing adds_in_progress, plus the excess needed for this 5470db9d74eSMina Almasry * operation. 5485e911373SMike Kravetz */ 5490db9d74eSMina Almasry if (actual_regions_needed > in_regions_needed && 5500db9d74eSMina Almasry resv->region_cache_count < 5510db9d74eSMina Almasry resv->adds_in_progress + 5520db9d74eSMina Almasry (actual_regions_needed - in_regions_needed)) { 5530db9d74eSMina Almasry /* region_add operation of range 1 should never need to 5540db9d74eSMina Almasry * allocate file_region entries. 5550db9d74eSMina Almasry */ 5560db9d74eSMina Almasry VM_BUG_ON(t - f <= 1); 5575e911373SMike Kravetz 5580db9d74eSMina Almasry if (allocate_file_region_entries( 5590db9d74eSMina Almasry resv, actual_regions_needed - in_regions_needed)) { 5600db9d74eSMina Almasry return -ENOMEM; 5615e911373SMike Kravetz } 5625e911373SMike Kravetz 5630db9d74eSMina Almasry goto retry; 5640db9d74eSMina Almasry } 565cf3ad20bSMike Kravetz 566972a3da3SWei Yang add = add_reservation_in_range(resv, f, t, h_cg, h, NULL); 5670db9d74eSMina Almasry 5680db9d74eSMina Almasry resv->adds_in_progress -= in_regions_needed; 5690db9d74eSMina Almasry 5707b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 571cf3ad20bSMike Kravetz return add; 57296822904SAndy Whitcroft } 57396822904SAndy Whitcroft 5741dd308a7SMike Kravetz /* 5751dd308a7SMike Kravetz * Examine the existing reserve map and determine how many 5761dd308a7SMike Kravetz * huge pages in the specified range [f, t) are NOT currently 5771dd308a7SMike Kravetz * represented. This routine is called before a subsequent 5781dd308a7SMike Kravetz * call to region_add that will actually modify the reserve 5791dd308a7SMike Kravetz * map to add the specified range [f, t). region_chg does 5801dd308a7SMike Kravetz * not change the number of huge pages represented by the 5810db9d74eSMina Almasry * map. A number of new file_region structures is added to the cache as a 5820db9d74eSMina Almasry * placeholder, for the subsequent region_add call to use. At least 1 5830db9d74eSMina Almasry * file_region structure is added. 5840db9d74eSMina Almasry * 5850db9d74eSMina Almasry * out_regions_needed is the number of regions added to the 5860db9d74eSMina Almasry * resv->adds_in_progress. This value needs to be provided to a follow up call 5870db9d74eSMina Almasry * to region_add or region_abort for proper accounting. 5885e911373SMike Kravetz * 5895e911373SMike Kravetz * Returns the number of huge pages that need to be added to the existing 5905e911373SMike Kravetz * reservation map for the range [f, t). This number is greater or equal to 5915e911373SMike Kravetz * zero. -ENOMEM is returned if a new file_region structure or cache entry 5925e911373SMike Kravetz * is needed and can not be allocated. 5931dd308a7SMike Kravetz */ 5940db9d74eSMina Almasry static long region_chg(struct resv_map *resv, long f, long t, 5950db9d74eSMina Almasry long *out_regions_needed) 59696822904SAndy Whitcroft { 59796822904SAndy Whitcroft long chg = 0; 59896822904SAndy Whitcroft 5997b24d861SDavidlohr Bueso spin_lock(&resv->lock); 6005e911373SMike Kravetz 601972a3da3SWei Yang /* Count how many hugepages in this range are NOT represented. */ 602075a61d0SMina Almasry chg = add_reservation_in_range(resv, f, t, NULL, NULL, 603972a3da3SWei Yang out_regions_needed); 6045e911373SMike Kravetz 6050db9d74eSMina Almasry if (*out_regions_needed == 0) 6060db9d74eSMina Almasry *out_regions_needed = 1; 6075e911373SMike Kravetz 6080db9d74eSMina Almasry if (allocate_file_region_entries(resv, *out_regions_needed)) 6095e911373SMike Kravetz return -ENOMEM; 6105e911373SMike Kravetz 6110db9d74eSMina Almasry resv->adds_in_progress += *out_regions_needed; 61296822904SAndy Whitcroft 6137b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 61496822904SAndy Whitcroft return chg; 61596822904SAndy Whitcroft } 61696822904SAndy Whitcroft 6171dd308a7SMike Kravetz /* 6185e911373SMike Kravetz * Abort the in progress add operation. The adds_in_progress field 6195e911373SMike Kravetz * of the resv_map keeps track of the operations in progress between 6205e911373SMike Kravetz * calls to region_chg and region_add. Operations are sometimes 6215e911373SMike Kravetz * aborted after the call to region_chg. In such cases, region_abort 6220db9d74eSMina Almasry * is called to decrement the adds_in_progress counter. regions_needed 6230db9d74eSMina Almasry * is the value returned by the region_chg call, it is used to decrement 6240db9d74eSMina Almasry * the adds_in_progress counter. 6255e911373SMike Kravetz * 6265e911373SMike Kravetz * NOTE: The range arguments [f, t) are not needed or used in this 6275e911373SMike Kravetz * routine. They are kept to make reading the calling code easier as 6285e911373SMike Kravetz * arguments will match the associated region_chg call. 6295e911373SMike Kravetz */ 6300db9d74eSMina Almasry static void region_abort(struct resv_map *resv, long f, long t, 6310db9d74eSMina Almasry long regions_needed) 6325e911373SMike Kravetz { 6335e911373SMike Kravetz spin_lock(&resv->lock); 6345e911373SMike Kravetz VM_BUG_ON(!resv->region_cache_count); 6350db9d74eSMina Almasry resv->adds_in_progress -= regions_needed; 6365e911373SMike Kravetz spin_unlock(&resv->lock); 6375e911373SMike Kravetz } 6385e911373SMike Kravetz 6395e911373SMike Kravetz /* 640feba16e2SMike Kravetz * Delete the specified range [f, t) from the reserve map. If the 641feba16e2SMike Kravetz * t parameter is LONG_MAX, this indicates that ALL regions after f 642feba16e2SMike Kravetz * should be deleted. Locate the regions which intersect [f, t) 643feba16e2SMike Kravetz * and either trim, delete or split the existing regions. 644feba16e2SMike Kravetz * 645feba16e2SMike Kravetz * Returns the number of huge pages deleted from the reserve map. 646feba16e2SMike Kravetz * In the normal case, the return value is zero or more. In the 647feba16e2SMike Kravetz * case where a region must be split, a new region descriptor must 648feba16e2SMike Kravetz * be allocated. If the allocation fails, -ENOMEM will be returned. 649feba16e2SMike Kravetz * NOTE: If the parameter t == LONG_MAX, then we will never split 650feba16e2SMike Kravetz * a region and possibly return -ENOMEM. Callers specifying 651feba16e2SMike Kravetz * t == LONG_MAX do not need to check for -ENOMEM error. 6521dd308a7SMike Kravetz */ 653feba16e2SMike Kravetz static long region_del(struct resv_map *resv, long f, long t) 65496822904SAndy Whitcroft { 6551406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 65696822904SAndy Whitcroft struct file_region *rg, *trg; 657feba16e2SMike Kravetz struct file_region *nrg = NULL; 658feba16e2SMike Kravetz long del = 0; 65996822904SAndy Whitcroft 660feba16e2SMike Kravetz retry: 6617b24d861SDavidlohr Bueso spin_lock(&resv->lock); 662feba16e2SMike Kravetz list_for_each_entry_safe(rg, trg, head, link) { 663dbe409e4SMike Kravetz /* 664dbe409e4SMike Kravetz * Skip regions before the range to be deleted. file_region 665dbe409e4SMike Kravetz * ranges are normally of the form [from, to). However, there 666dbe409e4SMike Kravetz * may be a "placeholder" entry in the map which is of the form 667dbe409e4SMike Kravetz * (from, to) with from == to. Check for placeholder entries 668dbe409e4SMike Kravetz * at the beginning of the range to be deleted. 669dbe409e4SMike Kravetz */ 670dbe409e4SMike Kravetz if (rg->to <= f && (rg->to != rg->from || rg->to != f)) 671feba16e2SMike Kravetz continue; 672dbe409e4SMike Kravetz 673feba16e2SMike Kravetz if (rg->from >= t) 67496822904SAndy Whitcroft break; 67596822904SAndy Whitcroft 676feba16e2SMike Kravetz if (f > rg->from && t < rg->to) { /* Must split region */ 677feba16e2SMike Kravetz /* 678feba16e2SMike Kravetz * Check for an entry in the cache before dropping 679feba16e2SMike Kravetz * lock and attempting allocation. 680feba16e2SMike Kravetz */ 681feba16e2SMike Kravetz if (!nrg && 682feba16e2SMike Kravetz resv->region_cache_count > resv->adds_in_progress) { 683feba16e2SMike Kravetz nrg = list_first_entry(&resv->region_cache, 684feba16e2SMike Kravetz struct file_region, 685feba16e2SMike Kravetz link); 686feba16e2SMike Kravetz list_del(&nrg->link); 687feba16e2SMike Kravetz resv->region_cache_count--; 68896822904SAndy Whitcroft } 68996822904SAndy Whitcroft 690feba16e2SMike Kravetz if (!nrg) { 691feba16e2SMike Kravetz spin_unlock(&resv->lock); 692feba16e2SMike Kravetz nrg = kmalloc(sizeof(*nrg), GFP_KERNEL); 693feba16e2SMike Kravetz if (!nrg) 694feba16e2SMike Kravetz return -ENOMEM; 695feba16e2SMike Kravetz goto retry; 696feba16e2SMike Kravetz } 697feba16e2SMike Kravetz 698feba16e2SMike Kravetz del += t - f; 69979aa925bSMike Kravetz hugetlb_cgroup_uncharge_file_region( 700d85aecf2SMiaohe Lin resv, rg, t - f, false); 701feba16e2SMike Kravetz 702feba16e2SMike Kravetz /* New entry for end of split region */ 703feba16e2SMike Kravetz nrg->from = t; 704feba16e2SMike Kravetz nrg->to = rg->to; 705075a61d0SMina Almasry 706075a61d0SMina Almasry copy_hugetlb_cgroup_uncharge_info(nrg, rg); 707075a61d0SMina Almasry 708feba16e2SMike Kravetz INIT_LIST_HEAD(&nrg->link); 709feba16e2SMike Kravetz 710feba16e2SMike Kravetz /* Original entry is trimmed */ 711feba16e2SMike Kravetz rg->to = f; 712feba16e2SMike Kravetz 713feba16e2SMike Kravetz list_add(&nrg->link, &rg->link); 714feba16e2SMike Kravetz nrg = NULL; 71596822904SAndy Whitcroft break; 716feba16e2SMike Kravetz } 717feba16e2SMike Kravetz 718feba16e2SMike Kravetz if (f <= rg->from && t >= rg->to) { /* Remove entire region */ 719feba16e2SMike Kravetz del += rg->to - rg->from; 720075a61d0SMina Almasry hugetlb_cgroup_uncharge_file_region(resv, rg, 721d85aecf2SMiaohe Lin rg->to - rg->from, true); 72296822904SAndy Whitcroft list_del(&rg->link); 72396822904SAndy Whitcroft kfree(rg); 724feba16e2SMike Kravetz continue; 72596822904SAndy Whitcroft } 7267b24d861SDavidlohr Bueso 727feba16e2SMike Kravetz if (f <= rg->from) { /* Trim beginning of region */ 728075a61d0SMina Almasry hugetlb_cgroup_uncharge_file_region(resv, rg, 729d85aecf2SMiaohe Lin t - rg->from, false); 730075a61d0SMina Almasry 73179aa925bSMike Kravetz del += t - rg->from; 73279aa925bSMike Kravetz rg->from = t; 73379aa925bSMike Kravetz } else { /* Trim end of region */ 734075a61d0SMina Almasry hugetlb_cgroup_uncharge_file_region(resv, rg, 735d85aecf2SMiaohe Lin rg->to - f, false); 73679aa925bSMike Kravetz 73779aa925bSMike Kravetz del += rg->to - f; 73879aa925bSMike Kravetz rg->to = f; 739feba16e2SMike Kravetz } 740feba16e2SMike Kravetz } 741feba16e2SMike Kravetz 7427b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 743feba16e2SMike Kravetz kfree(nrg); 744feba16e2SMike Kravetz return del; 74596822904SAndy Whitcroft } 74696822904SAndy Whitcroft 7471dd308a7SMike Kravetz /* 748b5cec28dSMike Kravetz * A rare out of memory error was encountered which prevented removal of 749b5cec28dSMike Kravetz * the reserve map region for a page. The huge page itself was free'ed 750b5cec28dSMike Kravetz * and removed from the page cache. This routine will adjust the subpool 751b5cec28dSMike Kravetz * usage count, and the global reserve count if needed. By incrementing 752b5cec28dSMike Kravetz * these counts, the reserve map entry which could not be deleted will 753b5cec28dSMike Kravetz * appear as a "reserved" entry instead of simply dangling with incorrect 754b5cec28dSMike Kravetz * counts. 755b5cec28dSMike Kravetz */ 75672e2936cSzhong jiang void hugetlb_fix_reserve_counts(struct inode *inode) 757b5cec28dSMike Kravetz { 758b5cec28dSMike Kravetz struct hugepage_subpool *spool = subpool_inode(inode); 759b5cec28dSMike Kravetz long rsv_adjust; 760da56388cSMiaohe Lin bool reserved = false; 761b5cec28dSMike Kravetz 762b5cec28dSMike Kravetz rsv_adjust = hugepage_subpool_get_pages(spool, 1); 763da56388cSMiaohe Lin if (rsv_adjust > 0) { 764b5cec28dSMike Kravetz struct hstate *h = hstate_inode(inode); 765b5cec28dSMike Kravetz 766da56388cSMiaohe Lin if (!hugetlb_acct_memory(h, 1)) 767da56388cSMiaohe Lin reserved = true; 768da56388cSMiaohe Lin } else if (!rsv_adjust) { 769da56388cSMiaohe Lin reserved = true; 770b5cec28dSMike Kravetz } 771da56388cSMiaohe Lin 772da56388cSMiaohe Lin if (!reserved) 773da56388cSMiaohe Lin pr_warn("hugetlb: Huge Page Reserved count may go negative.\n"); 774b5cec28dSMike Kravetz } 775b5cec28dSMike Kravetz 776b5cec28dSMike Kravetz /* 7771dd308a7SMike Kravetz * Count and return the number of huge pages in the reserve map 7781dd308a7SMike Kravetz * that intersect with the range [f, t). 7791dd308a7SMike Kravetz */ 7801406ec9bSJoonsoo Kim static long region_count(struct resv_map *resv, long f, long t) 78184afd99bSAndy Whitcroft { 7821406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 78384afd99bSAndy Whitcroft struct file_region *rg; 78484afd99bSAndy Whitcroft long chg = 0; 78584afd99bSAndy Whitcroft 7867b24d861SDavidlohr Bueso spin_lock(&resv->lock); 78784afd99bSAndy Whitcroft /* Locate each segment we overlap with, and count that overlap. */ 78884afd99bSAndy Whitcroft list_for_each_entry(rg, head, link) { 789f2135a4aSWang Sheng-Hui long seg_from; 790f2135a4aSWang Sheng-Hui long seg_to; 79184afd99bSAndy Whitcroft 79284afd99bSAndy Whitcroft if (rg->to <= f) 79384afd99bSAndy Whitcroft continue; 79484afd99bSAndy Whitcroft if (rg->from >= t) 79584afd99bSAndy Whitcroft break; 79684afd99bSAndy Whitcroft 79784afd99bSAndy Whitcroft seg_from = max(rg->from, f); 79884afd99bSAndy Whitcroft seg_to = min(rg->to, t); 79984afd99bSAndy Whitcroft 80084afd99bSAndy Whitcroft chg += seg_to - seg_from; 80184afd99bSAndy Whitcroft } 8027b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 80384afd99bSAndy Whitcroft 80484afd99bSAndy Whitcroft return chg; 80584afd99bSAndy Whitcroft } 80684afd99bSAndy Whitcroft 80796822904SAndy Whitcroft /* 808e7c4b0bfSAndy Whitcroft * Convert the address within this vma to the page offset within 809e7c4b0bfSAndy Whitcroft * the mapping, in pagecache page units; huge pages here. 810e7c4b0bfSAndy Whitcroft */ 811a5516438SAndi Kleen static pgoff_t vma_hugecache_offset(struct hstate *h, 812a5516438SAndi Kleen struct vm_area_struct *vma, unsigned long address) 813e7c4b0bfSAndy Whitcroft { 814a5516438SAndi Kleen return ((address - vma->vm_start) >> huge_page_shift(h)) + 815a5516438SAndi Kleen (vma->vm_pgoff >> huge_page_order(h)); 816e7c4b0bfSAndy Whitcroft } 817e7c4b0bfSAndy Whitcroft 8180fe6e20bSNaoya Horiguchi pgoff_t linear_hugepage_index(struct vm_area_struct *vma, 8190fe6e20bSNaoya Horiguchi unsigned long address) 8200fe6e20bSNaoya Horiguchi { 8210fe6e20bSNaoya Horiguchi return vma_hugecache_offset(hstate_vma(vma), vma, address); 8220fe6e20bSNaoya Horiguchi } 823dee41079SDan Williams EXPORT_SYMBOL_GPL(linear_hugepage_index); 8240fe6e20bSNaoya Horiguchi 82584afd99bSAndy Whitcroft /* 82608fba699SMel Gorman * Return the size of the pages allocated when backing a VMA. In the majority 82708fba699SMel Gorman * cases this will be same size as used by the page table entries. 82808fba699SMel Gorman */ 82908fba699SMel Gorman unsigned long vma_kernel_pagesize(struct vm_area_struct *vma) 83008fba699SMel Gorman { 83105ea8860SDan Williams if (vma->vm_ops && vma->vm_ops->pagesize) 83205ea8860SDan Williams return vma->vm_ops->pagesize(vma); 83308fba699SMel Gorman return PAGE_SIZE; 83408fba699SMel Gorman } 835f340ca0fSJoerg Roedel EXPORT_SYMBOL_GPL(vma_kernel_pagesize); 83608fba699SMel Gorman 83708fba699SMel Gorman /* 8383340289dSMel Gorman * Return the page size being used by the MMU to back a VMA. In the majority 8393340289dSMel Gorman * of cases, the page size used by the kernel matches the MMU size. On 84009135cc5SDan Williams * architectures where it differs, an architecture-specific 'strong' 84109135cc5SDan Williams * version of this symbol is required. 8423340289dSMel Gorman */ 84309135cc5SDan Williams __weak unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) 8443340289dSMel Gorman { 8453340289dSMel Gorman return vma_kernel_pagesize(vma); 8463340289dSMel Gorman } 8473340289dSMel Gorman 8483340289dSMel Gorman /* 84984afd99bSAndy Whitcroft * Flags for MAP_PRIVATE reservations. These are stored in the bottom 85084afd99bSAndy Whitcroft * bits of the reservation map pointer, which are always clear due to 85184afd99bSAndy Whitcroft * alignment. 85284afd99bSAndy Whitcroft */ 85384afd99bSAndy Whitcroft #define HPAGE_RESV_OWNER (1UL << 0) 85484afd99bSAndy Whitcroft #define HPAGE_RESV_UNMAPPED (1UL << 1) 85504f2cbe3SMel Gorman #define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED) 85684afd99bSAndy Whitcroft 857a1e78772SMel Gorman /* 858a1e78772SMel Gorman * These helpers are used to track how many pages are reserved for 859a1e78772SMel Gorman * faults in a MAP_PRIVATE mapping. Only the process that called mmap() 860a1e78772SMel Gorman * is guaranteed to have their future faults succeed. 861a1e78772SMel Gorman * 862a1e78772SMel Gorman * With the exception of reset_vma_resv_huge_pages() which is called at fork(), 863a1e78772SMel Gorman * the reserve counters are updated with the hugetlb_lock held. It is safe 864a1e78772SMel Gorman * to reset the VMA at fork() time as it is not in use yet and there is no 865a1e78772SMel Gorman * chance of the global counters getting corrupted as a result of the values. 86684afd99bSAndy Whitcroft * 86784afd99bSAndy Whitcroft * The private mapping reservation is represented in a subtly different 86884afd99bSAndy Whitcroft * manner to a shared mapping. A shared mapping has a region map associated 86984afd99bSAndy Whitcroft * with the underlying file, this region map represents the backing file 87084afd99bSAndy Whitcroft * pages which have ever had a reservation assigned which this persists even 87184afd99bSAndy Whitcroft * after the page is instantiated. A private mapping has a region map 87284afd99bSAndy Whitcroft * associated with the original mmap which is attached to all VMAs which 87384afd99bSAndy Whitcroft * reference it, this region map represents those offsets which have consumed 87484afd99bSAndy Whitcroft * reservation ie. where pages have been instantiated. 875a1e78772SMel Gorman */ 876e7c4b0bfSAndy Whitcroft static unsigned long get_vma_private_data(struct vm_area_struct *vma) 877e7c4b0bfSAndy Whitcroft { 878e7c4b0bfSAndy Whitcroft return (unsigned long)vma->vm_private_data; 879e7c4b0bfSAndy Whitcroft } 880e7c4b0bfSAndy Whitcroft 881e7c4b0bfSAndy Whitcroft static void set_vma_private_data(struct vm_area_struct *vma, 882e7c4b0bfSAndy Whitcroft unsigned long value) 883e7c4b0bfSAndy Whitcroft { 884e7c4b0bfSAndy Whitcroft vma->vm_private_data = (void *)value; 885e7c4b0bfSAndy Whitcroft } 886e7c4b0bfSAndy Whitcroft 887e9fe92aeSMina Almasry static void 888e9fe92aeSMina Almasry resv_map_set_hugetlb_cgroup_uncharge_info(struct resv_map *resv_map, 889e9fe92aeSMina Almasry struct hugetlb_cgroup *h_cg, 890e9fe92aeSMina Almasry struct hstate *h) 891e9fe92aeSMina Almasry { 892e9fe92aeSMina Almasry #ifdef CONFIG_CGROUP_HUGETLB 893e9fe92aeSMina Almasry if (!h_cg || !h) { 894e9fe92aeSMina Almasry resv_map->reservation_counter = NULL; 895e9fe92aeSMina Almasry resv_map->pages_per_hpage = 0; 896e9fe92aeSMina Almasry resv_map->css = NULL; 897e9fe92aeSMina Almasry } else { 898e9fe92aeSMina Almasry resv_map->reservation_counter = 899e9fe92aeSMina Almasry &h_cg->rsvd_hugepage[hstate_index(h)]; 900e9fe92aeSMina Almasry resv_map->pages_per_hpage = pages_per_huge_page(h); 901e9fe92aeSMina Almasry resv_map->css = &h_cg->css; 902e9fe92aeSMina Almasry } 903e9fe92aeSMina Almasry #endif 904e9fe92aeSMina Almasry } 905e9fe92aeSMina Almasry 9069119a41eSJoonsoo Kim struct resv_map *resv_map_alloc(void) 90784afd99bSAndy Whitcroft { 90884afd99bSAndy Whitcroft struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL); 9095e911373SMike Kravetz struct file_region *rg = kmalloc(sizeof(*rg), GFP_KERNEL); 9105e911373SMike Kravetz 9115e911373SMike Kravetz if (!resv_map || !rg) { 9125e911373SMike Kravetz kfree(resv_map); 9135e911373SMike Kravetz kfree(rg); 91484afd99bSAndy Whitcroft return NULL; 9155e911373SMike Kravetz } 91684afd99bSAndy Whitcroft 91784afd99bSAndy Whitcroft kref_init(&resv_map->refs); 9187b24d861SDavidlohr Bueso spin_lock_init(&resv_map->lock); 91984afd99bSAndy Whitcroft INIT_LIST_HEAD(&resv_map->regions); 92084afd99bSAndy Whitcroft 9215e911373SMike Kravetz resv_map->adds_in_progress = 0; 922e9fe92aeSMina Almasry /* 923e9fe92aeSMina Almasry * Initialize these to 0. On shared mappings, 0's here indicate these 924e9fe92aeSMina Almasry * fields don't do cgroup accounting. On private mappings, these will be 925e9fe92aeSMina Almasry * re-initialized to the proper values, to indicate that hugetlb cgroup 926e9fe92aeSMina Almasry * reservations are to be un-charged from here. 927e9fe92aeSMina Almasry */ 928e9fe92aeSMina Almasry resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, NULL, NULL); 9295e911373SMike Kravetz 9305e911373SMike Kravetz INIT_LIST_HEAD(&resv_map->region_cache); 9315e911373SMike Kravetz list_add(&rg->link, &resv_map->region_cache); 9325e911373SMike Kravetz resv_map->region_cache_count = 1; 9335e911373SMike Kravetz 93484afd99bSAndy Whitcroft return resv_map; 93584afd99bSAndy Whitcroft } 93684afd99bSAndy Whitcroft 9379119a41eSJoonsoo Kim void resv_map_release(struct kref *ref) 93884afd99bSAndy Whitcroft { 93984afd99bSAndy Whitcroft struct resv_map *resv_map = container_of(ref, struct resv_map, refs); 9405e911373SMike Kravetz struct list_head *head = &resv_map->region_cache; 9415e911373SMike Kravetz struct file_region *rg, *trg; 94284afd99bSAndy Whitcroft 94384afd99bSAndy Whitcroft /* Clear out any active regions before we release the map. */ 944feba16e2SMike Kravetz region_del(resv_map, 0, LONG_MAX); 9455e911373SMike Kravetz 9465e911373SMike Kravetz /* ... and any entries left in the cache */ 9475e911373SMike Kravetz list_for_each_entry_safe(rg, trg, head, link) { 9485e911373SMike Kravetz list_del(&rg->link); 9495e911373SMike Kravetz kfree(rg); 9505e911373SMike Kravetz } 9515e911373SMike Kravetz 9525e911373SMike Kravetz VM_BUG_ON(resv_map->adds_in_progress); 9535e911373SMike Kravetz 95484afd99bSAndy Whitcroft kfree(resv_map); 95584afd99bSAndy Whitcroft } 95684afd99bSAndy Whitcroft 9574e35f483SJoonsoo Kim static inline struct resv_map *inode_resv_map(struct inode *inode) 9584e35f483SJoonsoo Kim { 959f27a5136SMike Kravetz /* 960f27a5136SMike Kravetz * At inode evict time, i_mapping may not point to the original 961f27a5136SMike Kravetz * address space within the inode. This original address space 962f27a5136SMike Kravetz * contains the pointer to the resv_map. So, always use the 963f27a5136SMike Kravetz * address space embedded within the inode. 964f27a5136SMike Kravetz * The VERY common case is inode->mapping == &inode->i_data but, 965f27a5136SMike Kravetz * this may not be true for device special inodes. 966f27a5136SMike Kravetz */ 967f27a5136SMike Kravetz return (struct resv_map *)(&inode->i_data)->private_data; 9684e35f483SJoonsoo Kim } 9694e35f483SJoonsoo Kim 97084afd99bSAndy Whitcroft static struct resv_map *vma_resv_map(struct vm_area_struct *vma) 971a1e78772SMel Gorman { 97281d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 9734e35f483SJoonsoo Kim if (vma->vm_flags & VM_MAYSHARE) { 9744e35f483SJoonsoo Kim struct address_space *mapping = vma->vm_file->f_mapping; 9754e35f483SJoonsoo Kim struct inode *inode = mapping->host; 9764e35f483SJoonsoo Kim 9774e35f483SJoonsoo Kim return inode_resv_map(inode); 9784e35f483SJoonsoo Kim 9794e35f483SJoonsoo Kim } else { 98084afd99bSAndy Whitcroft return (struct resv_map *)(get_vma_private_data(vma) & 98184afd99bSAndy Whitcroft ~HPAGE_RESV_MASK); 9824e35f483SJoonsoo Kim } 983a1e78772SMel Gorman } 984a1e78772SMel Gorman 98584afd99bSAndy Whitcroft static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map) 986a1e78772SMel Gorman { 98781d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 98881d1b09cSSasha Levin VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); 989a1e78772SMel Gorman 99084afd99bSAndy Whitcroft set_vma_private_data(vma, (get_vma_private_data(vma) & 99184afd99bSAndy Whitcroft HPAGE_RESV_MASK) | (unsigned long)map); 99204f2cbe3SMel Gorman } 99304f2cbe3SMel Gorman 99404f2cbe3SMel Gorman static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags) 99504f2cbe3SMel Gorman { 99681d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 99781d1b09cSSasha Levin VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); 998e7c4b0bfSAndy Whitcroft 999e7c4b0bfSAndy Whitcroft set_vma_private_data(vma, get_vma_private_data(vma) | flags); 100004f2cbe3SMel Gorman } 100104f2cbe3SMel Gorman 100204f2cbe3SMel Gorman static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag) 100304f2cbe3SMel Gorman { 100481d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 1005e7c4b0bfSAndy Whitcroft 1006e7c4b0bfSAndy Whitcroft return (get_vma_private_data(vma) & flag) != 0; 1007a1e78772SMel Gorman } 1008a1e78772SMel Gorman 100904f2cbe3SMel Gorman /* Reset counters to 0 and clear all HPAGE_RESV_* flags */ 1010a1e78772SMel Gorman void reset_vma_resv_huge_pages(struct vm_area_struct *vma) 1011a1e78772SMel Gorman { 101281d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 1013f83a275dSMel Gorman if (!(vma->vm_flags & VM_MAYSHARE)) 1014a1e78772SMel Gorman vma->vm_private_data = (void *)0; 1015a1e78772SMel Gorman } 1016a1e78772SMel Gorman 1017a1e78772SMel Gorman /* Returns true if the VMA has associated reserve pages */ 1018559ec2f8SNicholas Krause static bool vma_has_reserves(struct vm_area_struct *vma, long chg) 1019a1e78772SMel Gorman { 1020af0ed73eSJoonsoo Kim if (vma->vm_flags & VM_NORESERVE) { 1021af0ed73eSJoonsoo Kim /* 1022af0ed73eSJoonsoo Kim * This address is already reserved by other process(chg == 0), 1023af0ed73eSJoonsoo Kim * so, we should decrement reserved count. Without decrementing, 1024af0ed73eSJoonsoo Kim * reserve count remains after releasing inode, because this 1025af0ed73eSJoonsoo Kim * allocated page will go into page cache and is regarded as 1026af0ed73eSJoonsoo Kim * coming from reserved pool in releasing step. Currently, we 1027af0ed73eSJoonsoo Kim * don't have any other solution to deal with this situation 1028af0ed73eSJoonsoo Kim * properly, so add work-around here. 1029af0ed73eSJoonsoo Kim */ 1030af0ed73eSJoonsoo Kim if (vma->vm_flags & VM_MAYSHARE && chg == 0) 1031559ec2f8SNicholas Krause return true; 1032af0ed73eSJoonsoo Kim else 1033559ec2f8SNicholas Krause return false; 1034af0ed73eSJoonsoo Kim } 1035a63884e9SJoonsoo Kim 1036a63884e9SJoonsoo Kim /* Shared mappings always use reserves */ 10371fb1b0e9SMike Kravetz if (vma->vm_flags & VM_MAYSHARE) { 10381fb1b0e9SMike Kravetz /* 10391fb1b0e9SMike Kravetz * We know VM_NORESERVE is not set. Therefore, there SHOULD 10401fb1b0e9SMike Kravetz * be a region map for all pages. The only situation where 10411fb1b0e9SMike Kravetz * there is no region map is if a hole was punched via 10427c8de358SEthon Paul * fallocate. In this case, there really are no reserves to 10431fb1b0e9SMike Kravetz * use. This situation is indicated if chg != 0. 10441fb1b0e9SMike Kravetz */ 10451fb1b0e9SMike Kravetz if (chg) 10461fb1b0e9SMike Kravetz return false; 10471fb1b0e9SMike Kravetz else 1048559ec2f8SNicholas Krause return true; 10491fb1b0e9SMike Kravetz } 1050a63884e9SJoonsoo Kim 1051a63884e9SJoonsoo Kim /* 1052a63884e9SJoonsoo Kim * Only the process that called mmap() has reserves for 1053a63884e9SJoonsoo Kim * private mappings. 1054a63884e9SJoonsoo Kim */ 105567961f9dSMike Kravetz if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { 105667961f9dSMike Kravetz /* 105767961f9dSMike Kravetz * Like the shared case above, a hole punch or truncate 105867961f9dSMike Kravetz * could have been performed on the private mapping. 105967961f9dSMike Kravetz * Examine the value of chg to determine if reserves 106067961f9dSMike Kravetz * actually exist or were previously consumed. 106167961f9dSMike Kravetz * Very Subtle - The value of chg comes from a previous 106267961f9dSMike Kravetz * call to vma_needs_reserves(). The reserve map for 106367961f9dSMike Kravetz * private mappings has different (opposite) semantics 106467961f9dSMike Kravetz * than that of shared mappings. vma_needs_reserves() 106567961f9dSMike Kravetz * has already taken this difference in semantics into 106667961f9dSMike Kravetz * account. Therefore, the meaning of chg is the same 106767961f9dSMike Kravetz * as in the shared case above. Code could easily be 106867961f9dSMike Kravetz * combined, but keeping it separate draws attention to 106967961f9dSMike Kravetz * subtle differences. 107067961f9dSMike Kravetz */ 107167961f9dSMike Kravetz if (chg) 107267961f9dSMike Kravetz return false; 107367961f9dSMike Kravetz else 1074559ec2f8SNicholas Krause return true; 107567961f9dSMike Kravetz } 1076a63884e9SJoonsoo Kim 1077559ec2f8SNicholas Krause return false; 1078a1e78772SMel Gorman } 1079a1e78772SMel Gorman 1080a5516438SAndi Kleen static void enqueue_huge_page(struct hstate *h, struct page *page) 10811da177e4SLinus Torvalds { 10821da177e4SLinus Torvalds int nid = page_to_nid(page); 10839487ca60SMike Kravetz 10849487ca60SMike Kravetz lockdep_assert_held(&hugetlb_lock); 1085b65a4edaSMike Kravetz VM_BUG_ON_PAGE(page_count(page), page); 1086b65a4edaSMike Kravetz 10870edaecfaSAneesh Kumar K.V list_move(&page->lru, &h->hugepage_freelists[nid]); 1088a5516438SAndi Kleen h->free_huge_pages++; 1089a5516438SAndi Kleen h->free_huge_pages_node[nid]++; 10906c037149SMike Kravetz SetHPageFreed(page); 10911da177e4SLinus Torvalds } 10921da177e4SLinus Torvalds 109394310cbcSAnshuman Khandual static struct page *dequeue_huge_page_node_exact(struct hstate *h, int nid) 1094bf50bab2SNaoya Horiguchi { 1095bf50bab2SNaoya Horiguchi struct page *page; 10961a08ae36SPavel Tatashin bool pin = !!(current->flags & PF_MEMALLOC_PIN); 1097bf50bab2SNaoya Horiguchi 10989487ca60SMike Kravetz lockdep_assert_held(&hugetlb_lock); 1099bbe88753SJoonsoo Kim list_for_each_entry(page, &h->hugepage_freelists[nid], lru) { 11008e3560d9SPavel Tatashin if (pin && !is_pinnable_page(page)) 1101bbe88753SJoonsoo Kim continue; 1102bbe88753SJoonsoo Kim 11036664bfc8SWei Yang if (PageHWPoison(page)) 11046664bfc8SWei Yang continue; 1105bbe88753SJoonsoo Kim 11060edaecfaSAneesh Kumar K.V list_move(&page->lru, &h->hugepage_activelist); 1107a9869b83SNaoya Horiguchi set_page_refcounted(page); 11086c037149SMike Kravetz ClearHPageFreed(page); 1109bf50bab2SNaoya Horiguchi h->free_huge_pages--; 1110bf50bab2SNaoya Horiguchi h->free_huge_pages_node[nid]--; 1111bf50bab2SNaoya Horiguchi return page; 1112bf50bab2SNaoya Horiguchi } 1113bf50bab2SNaoya Horiguchi 11146664bfc8SWei Yang return NULL; 11156664bfc8SWei Yang } 11166664bfc8SWei Yang 11173e59fcb0SMichal Hocko static struct page *dequeue_huge_page_nodemask(struct hstate *h, gfp_t gfp_mask, int nid, 11183e59fcb0SMichal Hocko nodemask_t *nmask) 111994310cbcSAnshuman Khandual { 11203e59fcb0SMichal Hocko unsigned int cpuset_mems_cookie; 11213e59fcb0SMichal Hocko struct zonelist *zonelist; 11223e59fcb0SMichal Hocko struct zone *zone; 11233e59fcb0SMichal Hocko struct zoneref *z; 112498fa15f3SAnshuman Khandual int node = NUMA_NO_NODE; 11253e59fcb0SMichal Hocko 11263e59fcb0SMichal Hocko zonelist = node_zonelist(nid, gfp_mask); 11273e59fcb0SMichal Hocko 11283e59fcb0SMichal Hocko retry_cpuset: 11293e59fcb0SMichal Hocko cpuset_mems_cookie = read_mems_allowed_begin(); 11303e59fcb0SMichal Hocko for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), nmask) { 113194310cbcSAnshuman Khandual struct page *page; 113294310cbcSAnshuman Khandual 11333e59fcb0SMichal Hocko if (!cpuset_zone_allowed(zone, gfp_mask)) 11343e59fcb0SMichal Hocko continue; 11353e59fcb0SMichal Hocko /* 11363e59fcb0SMichal Hocko * no need to ask again on the same node. Pool is node rather than 11373e59fcb0SMichal Hocko * zone aware 11383e59fcb0SMichal Hocko */ 11393e59fcb0SMichal Hocko if (zone_to_nid(zone) == node) 11403e59fcb0SMichal Hocko continue; 11413e59fcb0SMichal Hocko node = zone_to_nid(zone); 114294310cbcSAnshuman Khandual 114394310cbcSAnshuman Khandual page = dequeue_huge_page_node_exact(h, node); 114494310cbcSAnshuman Khandual if (page) 114594310cbcSAnshuman Khandual return page; 114694310cbcSAnshuman Khandual } 11473e59fcb0SMichal Hocko if (unlikely(read_mems_allowed_retry(cpuset_mems_cookie))) 11483e59fcb0SMichal Hocko goto retry_cpuset; 11493e59fcb0SMichal Hocko 115094310cbcSAnshuman Khandual return NULL; 115194310cbcSAnshuman Khandual } 115294310cbcSAnshuman Khandual 1153a5516438SAndi Kleen static struct page *dequeue_huge_page_vma(struct hstate *h, 1154a5516438SAndi Kleen struct vm_area_struct *vma, 1155af0ed73eSJoonsoo Kim unsigned long address, int avoid_reserve, 1156af0ed73eSJoonsoo Kim long chg) 11571da177e4SLinus Torvalds { 1158cfcaa66fSBen Widawsky struct page *page = NULL; 1159480eccf9SLee Schermerhorn struct mempolicy *mpol; 116004ec6264SVlastimil Babka gfp_t gfp_mask; 11613e59fcb0SMichal Hocko nodemask_t *nodemask; 116204ec6264SVlastimil Babka int nid; 11631da177e4SLinus Torvalds 1164a1e78772SMel Gorman /* 1165a1e78772SMel Gorman * A child process with MAP_PRIVATE mappings created by their parent 1166a1e78772SMel Gorman * have no page reserves. This check ensures that reservations are 1167a1e78772SMel Gorman * not "stolen". The child may still get SIGKILLed 1168a1e78772SMel Gorman */ 1169af0ed73eSJoonsoo Kim if (!vma_has_reserves(vma, chg) && 1170a5516438SAndi Kleen h->free_huge_pages - h->resv_huge_pages == 0) 1171c0ff7453SMiao Xie goto err; 1172a1e78772SMel Gorman 117304f2cbe3SMel Gorman /* If reserves cannot be used, ensure enough pages are in the pool */ 1174a5516438SAndi Kleen if (avoid_reserve && h->free_huge_pages - h->resv_huge_pages == 0) 11756eab04a8SJustin P. Mattock goto err; 117604f2cbe3SMel Gorman 117704ec6264SVlastimil Babka gfp_mask = htlb_alloc_mask(h); 117804ec6264SVlastimil Babka nid = huge_node(vma, address, gfp_mask, &mpol, &nodemask); 1179cfcaa66fSBen Widawsky 1180cfcaa66fSBen Widawsky if (mpol_is_preferred_many(mpol)) { 11813e59fcb0SMichal Hocko page = dequeue_huge_page_nodemask(h, gfp_mask, nid, nodemask); 1182cfcaa66fSBen Widawsky 1183cfcaa66fSBen Widawsky /* Fallback to all nodes if page==NULL */ 1184cfcaa66fSBen Widawsky nodemask = NULL; 1185cfcaa66fSBen Widawsky } 1186cfcaa66fSBen Widawsky 1187cfcaa66fSBen Widawsky if (!page) 1188cfcaa66fSBen Widawsky page = dequeue_huge_page_nodemask(h, gfp_mask, nid, nodemask); 1189cfcaa66fSBen Widawsky 11903e59fcb0SMichal Hocko if (page && !avoid_reserve && vma_has_reserves(vma, chg)) { 1191d6995da3SMike Kravetz SetHPageRestoreReserve(page); 1192a63884e9SJoonsoo Kim h->resv_huge_pages--; 1193bf50bab2SNaoya Horiguchi } 1194cc9a6c87SMel Gorman 1195cc9a6c87SMel Gorman mpol_cond_put(mpol); 1196cc9a6c87SMel Gorman return page; 1197cc9a6c87SMel Gorman 1198c0ff7453SMiao Xie err: 1199cc9a6c87SMel Gorman return NULL; 12001da177e4SLinus Torvalds } 12011da177e4SLinus Torvalds 12021cac6f2cSLuiz Capitulino /* 12031cac6f2cSLuiz Capitulino * common helper functions for hstate_next_node_to_{alloc|free}. 12041cac6f2cSLuiz Capitulino * We may have allocated or freed a huge page based on a different 12051cac6f2cSLuiz Capitulino * nodes_allowed previously, so h->next_node_to_{alloc|free} might 12061cac6f2cSLuiz Capitulino * be outside of *nodes_allowed. Ensure that we use an allowed 12071cac6f2cSLuiz Capitulino * node for alloc or free. 12081cac6f2cSLuiz Capitulino */ 12091cac6f2cSLuiz Capitulino static int next_node_allowed(int nid, nodemask_t *nodes_allowed) 12101cac6f2cSLuiz Capitulino { 12110edaf86cSAndrew Morton nid = next_node_in(nid, *nodes_allowed); 12121cac6f2cSLuiz Capitulino VM_BUG_ON(nid >= MAX_NUMNODES); 12131cac6f2cSLuiz Capitulino 12141cac6f2cSLuiz Capitulino return nid; 12151cac6f2cSLuiz Capitulino } 12161cac6f2cSLuiz Capitulino 12171cac6f2cSLuiz Capitulino static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed) 12181cac6f2cSLuiz Capitulino { 12191cac6f2cSLuiz Capitulino if (!node_isset(nid, *nodes_allowed)) 12201cac6f2cSLuiz Capitulino nid = next_node_allowed(nid, nodes_allowed); 12211cac6f2cSLuiz Capitulino return nid; 12221cac6f2cSLuiz Capitulino } 12231cac6f2cSLuiz Capitulino 12241cac6f2cSLuiz Capitulino /* 12251cac6f2cSLuiz Capitulino * returns the previously saved node ["this node"] from which to 12261cac6f2cSLuiz Capitulino * allocate a persistent huge page for the pool and advance the 12271cac6f2cSLuiz Capitulino * next node from which to allocate, handling wrap at end of node 12281cac6f2cSLuiz Capitulino * mask. 12291cac6f2cSLuiz Capitulino */ 12301cac6f2cSLuiz Capitulino static int hstate_next_node_to_alloc(struct hstate *h, 12311cac6f2cSLuiz Capitulino nodemask_t *nodes_allowed) 12321cac6f2cSLuiz Capitulino { 12331cac6f2cSLuiz Capitulino int nid; 12341cac6f2cSLuiz Capitulino 12351cac6f2cSLuiz Capitulino VM_BUG_ON(!nodes_allowed); 12361cac6f2cSLuiz Capitulino 12371cac6f2cSLuiz Capitulino nid = get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed); 12381cac6f2cSLuiz Capitulino h->next_nid_to_alloc = next_node_allowed(nid, nodes_allowed); 12391cac6f2cSLuiz Capitulino 12401cac6f2cSLuiz Capitulino return nid; 12411cac6f2cSLuiz Capitulino } 12421cac6f2cSLuiz Capitulino 12431cac6f2cSLuiz Capitulino /* 124410c6ec49SMike Kravetz * helper for remove_pool_huge_page() - return the previously saved 12451cac6f2cSLuiz Capitulino * node ["this node"] from which to free a huge page. Advance the 12461cac6f2cSLuiz Capitulino * next node id whether or not we find a free huge page to free so 12471cac6f2cSLuiz Capitulino * that the next attempt to free addresses the next node. 12481cac6f2cSLuiz Capitulino */ 12491cac6f2cSLuiz Capitulino static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed) 12501cac6f2cSLuiz Capitulino { 12511cac6f2cSLuiz Capitulino int nid; 12521cac6f2cSLuiz Capitulino 12531cac6f2cSLuiz Capitulino VM_BUG_ON(!nodes_allowed); 12541cac6f2cSLuiz Capitulino 12551cac6f2cSLuiz Capitulino nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed); 12561cac6f2cSLuiz Capitulino h->next_nid_to_free = next_node_allowed(nid, nodes_allowed); 12571cac6f2cSLuiz Capitulino 12581cac6f2cSLuiz Capitulino return nid; 12591cac6f2cSLuiz Capitulino } 12601cac6f2cSLuiz Capitulino 12611cac6f2cSLuiz Capitulino #define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask) \ 12621cac6f2cSLuiz Capitulino for (nr_nodes = nodes_weight(*mask); \ 12631cac6f2cSLuiz Capitulino nr_nodes > 0 && \ 12641cac6f2cSLuiz Capitulino ((node = hstate_next_node_to_alloc(hs, mask)) || 1); \ 12651cac6f2cSLuiz Capitulino nr_nodes--) 12661cac6f2cSLuiz Capitulino 12671cac6f2cSLuiz Capitulino #define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \ 12681cac6f2cSLuiz Capitulino for (nr_nodes = nodes_weight(*mask); \ 12691cac6f2cSLuiz Capitulino nr_nodes > 0 && \ 12701cac6f2cSLuiz Capitulino ((node = hstate_next_node_to_free(hs, mask)) || 1); \ 12711cac6f2cSLuiz Capitulino nr_nodes--) 12721cac6f2cSLuiz Capitulino 1273e1073d1eSAneesh Kumar K.V #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE 1274*34d9e35bSMike Kravetz static void __destroy_compound_gigantic_page(struct page *page, 1275*34d9e35bSMike Kravetz unsigned int order, bool demote) 1276944d9fecSLuiz Capitulino { 1277944d9fecSLuiz Capitulino int i; 1278944d9fecSLuiz Capitulino int nr_pages = 1 << order; 1279944d9fecSLuiz Capitulino struct page *p = page + 1; 1280944d9fecSLuiz Capitulino 1281c8cc708aSGerald Schaefer atomic_set(compound_mapcount_ptr(page), 0); 128247e29d32SJohn Hubbard atomic_set(compound_pincount_ptr(page), 0); 128347e29d32SJohn Hubbard 1284944d9fecSLuiz Capitulino for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { 1285a01f4390SMike Kravetz p->mapping = NULL; 12861d798ca3SKirill A. Shutemov clear_compound_head(p); 1287*34d9e35bSMike Kravetz if (!demote) 1288944d9fecSLuiz Capitulino set_page_refcounted(p); 1289944d9fecSLuiz Capitulino } 1290944d9fecSLuiz Capitulino 1291944d9fecSLuiz Capitulino set_compound_order(page, 0); 1292ba9c1201SGerald Schaefer page[1].compound_nr = 0; 1293944d9fecSLuiz Capitulino __ClearPageHead(page); 1294944d9fecSLuiz Capitulino } 1295944d9fecSLuiz Capitulino 1296*34d9e35bSMike Kravetz static void destroy_compound_gigantic_page(struct page *page, 1297*34d9e35bSMike Kravetz unsigned int order) 1298*34d9e35bSMike Kravetz { 1299*34d9e35bSMike Kravetz __destroy_compound_gigantic_page(page, order, false); 1300*34d9e35bSMike Kravetz } 1301*34d9e35bSMike Kravetz 1302d00181b9SKirill A. Shutemov static void free_gigantic_page(struct page *page, unsigned int order) 1303944d9fecSLuiz Capitulino { 1304cf11e85fSRoman Gushchin /* 1305cf11e85fSRoman Gushchin * If the page isn't allocated using the cma allocator, 1306cf11e85fSRoman Gushchin * cma_release() returns false. 1307cf11e85fSRoman Gushchin */ 1308dbda8feaSBarry Song #ifdef CONFIG_CMA 1309dbda8feaSBarry Song if (cma_release(hugetlb_cma[page_to_nid(page)], page, 1 << order)) 1310cf11e85fSRoman Gushchin return; 1311dbda8feaSBarry Song #endif 1312cf11e85fSRoman Gushchin 1313944d9fecSLuiz Capitulino free_contig_range(page_to_pfn(page), 1 << order); 1314944d9fecSLuiz Capitulino } 1315944d9fecSLuiz Capitulino 13164eb0716eSAlexandre Ghiti #ifdef CONFIG_CONTIG_ALLOC 1317d9cc948fSMichal Hocko static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask, 1318d9cc948fSMichal Hocko int nid, nodemask_t *nodemask) 1319944d9fecSLuiz Capitulino { 132004adbc3fSMiaohe Lin unsigned long nr_pages = pages_per_huge_page(h); 1321953f064aSLi Xinhai if (nid == NUMA_NO_NODE) 1322953f064aSLi Xinhai nid = numa_mem_id(); 1323944d9fecSLuiz Capitulino 1324dbda8feaSBarry Song #ifdef CONFIG_CMA 1325dbda8feaSBarry Song { 1326cf11e85fSRoman Gushchin struct page *page; 1327cf11e85fSRoman Gushchin int node; 1328cf11e85fSRoman Gushchin 1329953f064aSLi Xinhai if (hugetlb_cma[nid]) { 1330953f064aSLi Xinhai page = cma_alloc(hugetlb_cma[nid], nr_pages, 1331953f064aSLi Xinhai huge_page_order(h), true); 1332953f064aSLi Xinhai if (page) 1333953f064aSLi Xinhai return page; 1334953f064aSLi Xinhai } 1335953f064aSLi Xinhai 1336953f064aSLi Xinhai if (!(gfp_mask & __GFP_THISNODE)) { 1337cf11e85fSRoman Gushchin for_each_node_mask(node, *nodemask) { 1338953f064aSLi Xinhai if (node == nid || !hugetlb_cma[node]) 1339cf11e85fSRoman Gushchin continue; 1340cf11e85fSRoman Gushchin 1341cf11e85fSRoman Gushchin page = cma_alloc(hugetlb_cma[node], nr_pages, 1342cf11e85fSRoman Gushchin huge_page_order(h), true); 1343cf11e85fSRoman Gushchin if (page) 1344cf11e85fSRoman Gushchin return page; 1345cf11e85fSRoman Gushchin } 1346cf11e85fSRoman Gushchin } 1347953f064aSLi Xinhai } 1348dbda8feaSBarry Song #endif 1349cf11e85fSRoman Gushchin 13505e27a2dfSAnshuman Khandual return alloc_contig_pages(nr_pages, gfp_mask, nid, nodemask); 1351944d9fecSLuiz Capitulino } 1352944d9fecSLuiz Capitulino 13534eb0716eSAlexandre Ghiti #else /* !CONFIG_CONTIG_ALLOC */ 13544eb0716eSAlexandre Ghiti static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask, 13554eb0716eSAlexandre Ghiti int nid, nodemask_t *nodemask) 13564eb0716eSAlexandre Ghiti { 13574eb0716eSAlexandre Ghiti return NULL; 13584eb0716eSAlexandre Ghiti } 13594eb0716eSAlexandre Ghiti #endif /* CONFIG_CONTIG_ALLOC */ 1360944d9fecSLuiz Capitulino 1361e1073d1eSAneesh Kumar K.V #else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */ 1362d9cc948fSMichal Hocko static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask, 13634eb0716eSAlexandre Ghiti int nid, nodemask_t *nodemask) 13644eb0716eSAlexandre Ghiti { 13654eb0716eSAlexandre Ghiti return NULL; 13664eb0716eSAlexandre Ghiti } 1367d00181b9SKirill A. Shutemov static inline void free_gigantic_page(struct page *page, unsigned int order) { } 1368944d9fecSLuiz Capitulino static inline void destroy_compound_gigantic_page(struct page *page, 1369d00181b9SKirill A. Shutemov unsigned int order) { } 1370944d9fecSLuiz Capitulino #endif 1371944d9fecSLuiz Capitulino 13726eb4e88aSMike Kravetz /* 13736eb4e88aSMike Kravetz * Remove hugetlb page from lists, and update dtor so that page appears 1374*34d9e35bSMike Kravetz * as just a compound page. 1375*34d9e35bSMike Kravetz * 1376*34d9e35bSMike Kravetz * A reference is held on the page, except in the case of demote. 13776eb4e88aSMike Kravetz * 13786eb4e88aSMike Kravetz * Must be called with hugetlb lock held. 13796eb4e88aSMike Kravetz */ 1380*34d9e35bSMike Kravetz static void __remove_hugetlb_page(struct hstate *h, struct page *page, 1381*34d9e35bSMike Kravetz bool adjust_surplus, 1382*34d9e35bSMike Kravetz bool demote) 13836eb4e88aSMike Kravetz { 13846eb4e88aSMike Kravetz int nid = page_to_nid(page); 13856eb4e88aSMike Kravetz 13866eb4e88aSMike Kravetz VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page), page); 13876eb4e88aSMike Kravetz VM_BUG_ON_PAGE(hugetlb_cgroup_from_page_rsvd(page), page); 13886eb4e88aSMike Kravetz 13899487ca60SMike Kravetz lockdep_assert_held(&hugetlb_lock); 13906eb4e88aSMike Kravetz if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) 13916eb4e88aSMike Kravetz return; 13926eb4e88aSMike Kravetz 13936eb4e88aSMike Kravetz list_del(&page->lru); 13946eb4e88aSMike Kravetz 13956eb4e88aSMike Kravetz if (HPageFreed(page)) { 13966eb4e88aSMike Kravetz h->free_huge_pages--; 13976eb4e88aSMike Kravetz h->free_huge_pages_node[nid]--; 13986eb4e88aSMike Kravetz } 13996eb4e88aSMike Kravetz if (adjust_surplus) { 14006eb4e88aSMike Kravetz h->surplus_huge_pages--; 14016eb4e88aSMike Kravetz h->surplus_huge_pages_node[nid]--; 14026eb4e88aSMike Kravetz } 14036eb4e88aSMike Kravetz 1404e32d20c0SMike Kravetz /* 1405e32d20c0SMike Kravetz * Very subtle 1406e32d20c0SMike Kravetz * 1407e32d20c0SMike Kravetz * For non-gigantic pages set the destructor to the normal compound 1408e32d20c0SMike Kravetz * page dtor. This is needed in case someone takes an additional 1409e32d20c0SMike Kravetz * temporary ref to the page, and freeing is delayed until they drop 1410e32d20c0SMike Kravetz * their reference. 1411e32d20c0SMike Kravetz * 1412e32d20c0SMike Kravetz * For gigantic pages set the destructor to the null dtor. This 1413e32d20c0SMike Kravetz * destructor will never be called. Before freeing the gigantic 1414e32d20c0SMike Kravetz * page destroy_compound_gigantic_page will turn the compound page 1415e32d20c0SMike Kravetz * into a simple group of pages. After this the destructor does not 1416e32d20c0SMike Kravetz * apply. 1417e32d20c0SMike Kravetz * 1418e32d20c0SMike Kravetz * This handles the case where more than one ref is held when and 1419e32d20c0SMike Kravetz * after update_and_free_page is called. 1420*34d9e35bSMike Kravetz * 1421*34d9e35bSMike Kravetz * In the case of demote we do not ref count the page as it will soon 1422*34d9e35bSMike Kravetz * be turned into a page of smaller size. 1423e32d20c0SMike Kravetz */ 1424*34d9e35bSMike Kravetz if (!demote) 14256eb4e88aSMike Kravetz set_page_refcounted(page); 1426e32d20c0SMike Kravetz if (hstate_is_gigantic(h)) 14276eb4e88aSMike Kravetz set_compound_page_dtor(page, NULL_COMPOUND_DTOR); 1428e32d20c0SMike Kravetz else 1429e32d20c0SMike Kravetz set_compound_page_dtor(page, COMPOUND_PAGE_DTOR); 14306eb4e88aSMike Kravetz 14316eb4e88aSMike Kravetz h->nr_huge_pages--; 14326eb4e88aSMike Kravetz h->nr_huge_pages_node[nid]--; 14336eb4e88aSMike Kravetz } 14346eb4e88aSMike Kravetz 1435*34d9e35bSMike Kravetz static void remove_hugetlb_page(struct hstate *h, struct page *page, 1436*34d9e35bSMike Kravetz bool adjust_surplus) 1437*34d9e35bSMike Kravetz { 1438*34d9e35bSMike Kravetz __remove_hugetlb_page(h, page, adjust_surplus, false); 1439*34d9e35bSMike Kravetz } 1440*34d9e35bSMike Kravetz 1441ad2fa371SMuchun Song static void add_hugetlb_page(struct hstate *h, struct page *page, 1442ad2fa371SMuchun Song bool adjust_surplus) 1443ad2fa371SMuchun Song { 1444ad2fa371SMuchun Song int zeroed; 1445ad2fa371SMuchun Song int nid = page_to_nid(page); 1446ad2fa371SMuchun Song 1447ad2fa371SMuchun Song VM_BUG_ON_PAGE(!HPageVmemmapOptimized(page), page); 1448ad2fa371SMuchun Song 1449ad2fa371SMuchun Song lockdep_assert_held(&hugetlb_lock); 1450ad2fa371SMuchun Song 1451ad2fa371SMuchun Song INIT_LIST_HEAD(&page->lru); 1452ad2fa371SMuchun Song h->nr_huge_pages++; 1453ad2fa371SMuchun Song h->nr_huge_pages_node[nid]++; 1454ad2fa371SMuchun Song 1455ad2fa371SMuchun Song if (adjust_surplus) { 1456ad2fa371SMuchun Song h->surplus_huge_pages++; 1457ad2fa371SMuchun Song h->surplus_huge_pages_node[nid]++; 1458ad2fa371SMuchun Song } 1459ad2fa371SMuchun Song 1460ad2fa371SMuchun Song set_compound_page_dtor(page, HUGETLB_PAGE_DTOR); 1461ad2fa371SMuchun Song set_page_private(page, 0); 1462ad2fa371SMuchun Song SetHPageVmemmapOptimized(page); 1463ad2fa371SMuchun Song 1464ad2fa371SMuchun Song /* 1465b65a4edaSMike Kravetz * This page is about to be managed by the hugetlb allocator and 1466b65a4edaSMike Kravetz * should have no users. Drop our reference, and check for others 1467b65a4edaSMike Kravetz * just in case. 1468ad2fa371SMuchun Song */ 1469ad2fa371SMuchun Song zeroed = put_page_testzero(page); 1470b65a4edaSMike Kravetz if (!zeroed) 1471b65a4edaSMike Kravetz /* 1472b65a4edaSMike Kravetz * It is VERY unlikely soneone else has taken a ref on 1473b65a4edaSMike Kravetz * the page. In this case, we simply return as the 1474b65a4edaSMike Kravetz * hugetlb destructor (free_huge_page) will be called 1475b65a4edaSMike Kravetz * when this other ref is dropped. 1476b65a4edaSMike Kravetz */ 1477b65a4edaSMike Kravetz return; 1478b65a4edaSMike Kravetz 1479ad2fa371SMuchun Song arch_clear_hugepage_flags(page); 1480ad2fa371SMuchun Song enqueue_huge_page(h, page); 1481ad2fa371SMuchun Song } 1482ad2fa371SMuchun Song 1483b65d4adbSMuchun Song static void __update_and_free_page(struct hstate *h, struct page *page) 14846af2acb6SAdam Litke { 14856af2acb6SAdam Litke int i; 1486dbfee5aeSMike Kravetz struct page *subpage = page; 1487a5516438SAndi Kleen 14884eb0716eSAlexandre Ghiti if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) 1489944d9fecSLuiz Capitulino return; 149018229df5SAndy Whitcroft 1491ad2fa371SMuchun Song if (alloc_huge_page_vmemmap(h, page)) { 1492ad2fa371SMuchun Song spin_lock_irq(&hugetlb_lock); 1493ad2fa371SMuchun Song /* 1494ad2fa371SMuchun Song * If we cannot allocate vmemmap pages, just refuse to free the 1495ad2fa371SMuchun Song * page and put the page back on the hugetlb free list and treat 1496ad2fa371SMuchun Song * as a surplus page. 1497ad2fa371SMuchun Song */ 1498ad2fa371SMuchun Song add_hugetlb_page(h, page, true); 1499ad2fa371SMuchun Song spin_unlock_irq(&hugetlb_lock); 1500ad2fa371SMuchun Song return; 1501ad2fa371SMuchun Song } 1502ad2fa371SMuchun Song 1503dbfee5aeSMike Kravetz for (i = 0; i < pages_per_huge_page(h); 1504dbfee5aeSMike Kravetz i++, subpage = mem_map_next(subpage, page, i)) { 1505dbfee5aeSMike Kravetz subpage->flags &= ~(1 << PG_locked | 1 << PG_error | 150632f84528SChris Forbes 1 << PG_referenced | 1 << PG_dirty | 1507a7407a27SLuiz Capitulino 1 << PG_active | 1 << PG_private | 1508a7407a27SLuiz Capitulino 1 << PG_writeback); 15096af2acb6SAdam Litke } 1510a01f4390SMike Kravetz 1511a01f4390SMike Kravetz /* 1512a01f4390SMike Kravetz * Non-gigantic pages demoted from CMA allocated gigantic pages 1513a01f4390SMike Kravetz * need to be given back to CMA in free_gigantic_page. 1514a01f4390SMike Kravetz */ 1515a01f4390SMike Kravetz if (hstate_is_gigantic(h) || 1516a01f4390SMike Kravetz hugetlb_cma_page(page, huge_page_order(h))) { 1517944d9fecSLuiz Capitulino destroy_compound_gigantic_page(page, huge_page_order(h)); 1518944d9fecSLuiz Capitulino free_gigantic_page(page, huge_page_order(h)); 1519944d9fecSLuiz Capitulino } else { 1520a5516438SAndi Kleen __free_pages(page, huge_page_order(h)); 15216af2acb6SAdam Litke } 1522944d9fecSLuiz Capitulino } 15236af2acb6SAdam Litke 1524b65d4adbSMuchun Song /* 1525b65d4adbSMuchun Song * As update_and_free_page() can be called under any context, so we cannot 1526b65d4adbSMuchun Song * use GFP_KERNEL to allocate vmemmap pages. However, we can defer the 1527b65d4adbSMuchun Song * actual freeing in a workqueue to prevent from using GFP_ATOMIC to allocate 1528b65d4adbSMuchun Song * the vmemmap pages. 1529b65d4adbSMuchun Song * 1530b65d4adbSMuchun Song * free_hpage_workfn() locklessly retrieves the linked list of pages to be 1531b65d4adbSMuchun Song * freed and frees them one-by-one. As the page->mapping pointer is going 1532b65d4adbSMuchun Song * to be cleared in free_hpage_workfn() anyway, it is reused as the llist_node 1533b65d4adbSMuchun Song * structure of a lockless linked list of huge pages to be freed. 1534b65d4adbSMuchun Song */ 1535b65d4adbSMuchun Song static LLIST_HEAD(hpage_freelist); 1536b65d4adbSMuchun Song 1537b65d4adbSMuchun Song static void free_hpage_workfn(struct work_struct *work) 1538b65d4adbSMuchun Song { 1539b65d4adbSMuchun Song struct llist_node *node; 1540b65d4adbSMuchun Song 1541b65d4adbSMuchun Song node = llist_del_all(&hpage_freelist); 1542b65d4adbSMuchun Song 1543b65d4adbSMuchun Song while (node) { 1544b65d4adbSMuchun Song struct page *page; 1545b65d4adbSMuchun Song struct hstate *h; 1546b65d4adbSMuchun Song 1547b65d4adbSMuchun Song page = container_of((struct address_space **)node, 1548b65d4adbSMuchun Song struct page, mapping); 1549b65d4adbSMuchun Song node = node->next; 1550b65d4adbSMuchun Song page->mapping = NULL; 1551b65d4adbSMuchun Song /* 1552b65d4adbSMuchun Song * The VM_BUG_ON_PAGE(!PageHuge(page), page) in page_hstate() 1553b65d4adbSMuchun Song * is going to trigger because a previous call to 1554b65d4adbSMuchun Song * remove_hugetlb_page() will set_compound_page_dtor(page, 1555b65d4adbSMuchun Song * NULL_COMPOUND_DTOR), so do not use page_hstate() directly. 1556b65d4adbSMuchun Song */ 1557b65d4adbSMuchun Song h = size_to_hstate(page_size(page)); 1558b65d4adbSMuchun Song 1559b65d4adbSMuchun Song __update_and_free_page(h, page); 1560b65d4adbSMuchun Song 1561b65d4adbSMuchun Song cond_resched(); 1562b65d4adbSMuchun Song } 1563b65d4adbSMuchun Song } 1564b65d4adbSMuchun Song static DECLARE_WORK(free_hpage_work, free_hpage_workfn); 1565b65d4adbSMuchun Song 1566b65d4adbSMuchun Song static inline void flush_free_hpage_work(struct hstate *h) 1567b65d4adbSMuchun Song { 1568b65d4adbSMuchun Song if (free_vmemmap_pages_per_hpage(h)) 1569b65d4adbSMuchun Song flush_work(&free_hpage_work); 1570b65d4adbSMuchun Song } 1571b65d4adbSMuchun Song 1572b65d4adbSMuchun Song static void update_and_free_page(struct hstate *h, struct page *page, 1573b65d4adbSMuchun Song bool atomic) 1574b65d4adbSMuchun Song { 1575ad2fa371SMuchun Song if (!HPageVmemmapOptimized(page) || !atomic) { 1576b65d4adbSMuchun Song __update_and_free_page(h, page); 1577b65d4adbSMuchun Song return; 1578b65d4adbSMuchun Song } 1579b65d4adbSMuchun Song 1580b65d4adbSMuchun Song /* 1581b65d4adbSMuchun Song * Defer freeing to avoid using GFP_ATOMIC to allocate vmemmap pages. 1582b65d4adbSMuchun Song * 1583b65d4adbSMuchun Song * Only call schedule_work() if hpage_freelist is previously 1584b65d4adbSMuchun Song * empty. Otherwise, schedule_work() had been called but the workfn 1585b65d4adbSMuchun Song * hasn't retrieved the list yet. 1586b65d4adbSMuchun Song */ 1587b65d4adbSMuchun Song if (llist_add((struct llist_node *)&page->mapping, &hpage_freelist)) 1588b65d4adbSMuchun Song schedule_work(&free_hpage_work); 1589b65d4adbSMuchun Song } 1590b65d4adbSMuchun Song 159110c6ec49SMike Kravetz static void update_and_free_pages_bulk(struct hstate *h, struct list_head *list) 159210c6ec49SMike Kravetz { 159310c6ec49SMike Kravetz struct page *page, *t_page; 159410c6ec49SMike Kravetz 159510c6ec49SMike Kravetz list_for_each_entry_safe(page, t_page, list, lru) { 1596b65d4adbSMuchun Song update_and_free_page(h, page, false); 159710c6ec49SMike Kravetz cond_resched(); 159810c6ec49SMike Kravetz } 159910c6ec49SMike Kravetz } 160010c6ec49SMike Kravetz 1601e5ff2159SAndi Kleen struct hstate *size_to_hstate(unsigned long size) 1602e5ff2159SAndi Kleen { 1603e5ff2159SAndi Kleen struct hstate *h; 1604e5ff2159SAndi Kleen 1605e5ff2159SAndi Kleen for_each_hstate(h) { 1606e5ff2159SAndi Kleen if (huge_page_size(h) == size) 1607e5ff2159SAndi Kleen return h; 1608e5ff2159SAndi Kleen } 1609e5ff2159SAndi Kleen return NULL; 1610e5ff2159SAndi Kleen } 1611e5ff2159SAndi Kleen 1612db71ef79SMike Kravetz void free_huge_page(struct page *page) 161327a85ef1SDavid Gibson { 1614a5516438SAndi Kleen /* 1615a5516438SAndi Kleen * Can't pass hstate in here because it is called from the 1616a5516438SAndi Kleen * compound page destructor. 1617a5516438SAndi Kleen */ 1618e5ff2159SAndi Kleen struct hstate *h = page_hstate(page); 16197893d1d5SAdam Litke int nid = page_to_nid(page); 1620d6995da3SMike Kravetz struct hugepage_subpool *spool = hugetlb_page_subpool(page); 162107443a85SJoonsoo Kim bool restore_reserve; 1622db71ef79SMike Kravetz unsigned long flags; 162327a85ef1SDavid Gibson 1624b4330afbSMike Kravetz VM_BUG_ON_PAGE(page_count(page), page); 1625b4330afbSMike Kravetz VM_BUG_ON_PAGE(page_mapcount(page), page); 16268ace22bcSYongkai Wu 1627d6995da3SMike Kravetz hugetlb_set_page_subpool(page, NULL); 16288ace22bcSYongkai Wu page->mapping = NULL; 1629d6995da3SMike Kravetz restore_reserve = HPageRestoreReserve(page); 1630d6995da3SMike Kravetz ClearHPageRestoreReserve(page); 163127a85ef1SDavid Gibson 16321c5ecae3SMike Kravetz /* 1633d6995da3SMike Kravetz * If HPageRestoreReserve was set on page, page allocation consumed a 16340919e1b6SMike Kravetz * reservation. If the page was associated with a subpool, there 16350919e1b6SMike Kravetz * would have been a page reserved in the subpool before allocation 16360919e1b6SMike Kravetz * via hugepage_subpool_get_pages(). Since we are 'restoring' the 16376c26d310SMiaohe Lin * reservation, do not call hugepage_subpool_put_pages() as this will 16380919e1b6SMike Kravetz * remove the reserved page from the subpool. 16390919e1b6SMike Kravetz */ 16400919e1b6SMike Kravetz if (!restore_reserve) { 16410919e1b6SMike Kravetz /* 16420919e1b6SMike Kravetz * A return code of zero implies that the subpool will be 16430919e1b6SMike Kravetz * under its minimum size if the reservation is not restored 16440919e1b6SMike Kravetz * after page is free. Therefore, force restore_reserve 16450919e1b6SMike Kravetz * operation. 16461c5ecae3SMike Kravetz */ 16471c5ecae3SMike Kravetz if (hugepage_subpool_put_pages(spool, 1) == 0) 16481c5ecae3SMike Kravetz restore_reserve = true; 16490919e1b6SMike Kravetz } 16501c5ecae3SMike Kravetz 1651db71ef79SMike Kravetz spin_lock_irqsave(&hugetlb_lock, flags); 16528f251a3dSMike Kravetz ClearHPageMigratable(page); 16536d76dcf4SAneesh Kumar K.V hugetlb_cgroup_uncharge_page(hstate_index(h), 16546d76dcf4SAneesh Kumar K.V pages_per_huge_page(h), page); 165508cf9fafSMina Almasry hugetlb_cgroup_uncharge_page_rsvd(hstate_index(h), 165608cf9fafSMina Almasry pages_per_huge_page(h), page); 165707443a85SJoonsoo Kim if (restore_reserve) 165807443a85SJoonsoo Kim h->resv_huge_pages++; 165907443a85SJoonsoo Kim 16609157c311SMike Kravetz if (HPageTemporary(page)) { 16616eb4e88aSMike Kravetz remove_hugetlb_page(h, page, false); 1662db71ef79SMike Kravetz spin_unlock_irqrestore(&hugetlb_lock, flags); 1663b65d4adbSMuchun Song update_and_free_page(h, page, true); 1664ab5ac90aSMichal Hocko } else if (h->surplus_huge_pages_node[nid]) { 16650edaecfaSAneesh Kumar K.V /* remove the page from active list */ 16666eb4e88aSMike Kravetz remove_hugetlb_page(h, page, true); 1667db71ef79SMike Kravetz spin_unlock_irqrestore(&hugetlb_lock, flags); 1668b65d4adbSMuchun Song update_and_free_page(h, page, true); 16697893d1d5SAdam Litke } else { 16705d3a551cSWill Deacon arch_clear_hugepage_flags(page); 1671a5516438SAndi Kleen enqueue_huge_page(h, page); 1672db71ef79SMike Kravetz spin_unlock_irqrestore(&hugetlb_lock, flags); 167327a85ef1SDavid Gibson } 16741121828aSMike Kravetz } 167527a85ef1SDavid Gibson 1676d3d99fccSOscar Salvador /* 1677d3d99fccSOscar Salvador * Must be called with the hugetlb lock held 1678d3d99fccSOscar Salvador */ 1679d3d99fccSOscar Salvador static void __prep_account_new_huge_page(struct hstate *h, int nid) 1680d3d99fccSOscar Salvador { 1681d3d99fccSOscar Salvador lockdep_assert_held(&hugetlb_lock); 1682d3d99fccSOscar Salvador h->nr_huge_pages++; 1683d3d99fccSOscar Salvador h->nr_huge_pages_node[nid]++; 1684d3d99fccSOscar Salvador } 1685d3d99fccSOscar Salvador 1686f41f2ed4SMuchun Song static void __prep_new_huge_page(struct hstate *h, struct page *page) 1687b7ba30c6SAndi Kleen { 1688f41f2ed4SMuchun Song free_huge_page_vmemmap(h, page); 16890edaecfaSAneesh Kumar K.V INIT_LIST_HEAD(&page->lru); 1690f1e61557SKirill A. Shutemov set_compound_page_dtor(page, HUGETLB_PAGE_DTOR); 1691ff546117SMike Kravetz hugetlb_set_page_subpool(page, NULL); 16929dd540e2SAneesh Kumar K.V set_hugetlb_cgroup(page, NULL); 16931adc4d41SMina Almasry set_hugetlb_cgroup_rsvd(page, NULL); 1694d3d99fccSOscar Salvador } 1695d3d99fccSOscar Salvador 1696d3d99fccSOscar Salvador static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) 1697d3d99fccSOscar Salvador { 1698f41f2ed4SMuchun Song __prep_new_huge_page(h, page); 1699db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 1700d3d99fccSOscar Salvador __prep_account_new_huge_page(h, nid); 1701db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 1702b7ba30c6SAndi Kleen } 1703b7ba30c6SAndi Kleen 1704*34d9e35bSMike Kravetz static bool __prep_compound_gigantic_page(struct page *page, unsigned int order, 1705*34d9e35bSMike Kravetz bool demote) 170620a0307cSWu Fengguang { 17077118fc29SMike Kravetz int i, j; 170820a0307cSWu Fengguang int nr_pages = 1 << order; 170920a0307cSWu Fengguang struct page *p = page + 1; 171020a0307cSWu Fengguang 171120a0307cSWu Fengguang /* we rely on prep_new_huge_page to set the destructor */ 171220a0307cSWu Fengguang set_compound_order(page, order); 1713ef5a22beSAndrea Arcangeli __ClearPageReserved(page); 1714de09d31dSKirill A. Shutemov __SetPageHead(page); 171520a0307cSWu Fengguang for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { 1716ef5a22beSAndrea Arcangeli /* 1717ef5a22beSAndrea Arcangeli * For gigantic hugepages allocated through bootmem at 1718ef5a22beSAndrea Arcangeli * boot, it's safer to be consistent with the not-gigantic 1719ef5a22beSAndrea Arcangeli * hugepages and clear the PG_reserved bit from all tail pages 17207c8de358SEthon Paul * too. Otherwise drivers using get_user_pages() to access tail 1721ef5a22beSAndrea Arcangeli * pages may get the reference counting wrong if they see 1722ef5a22beSAndrea Arcangeli * PG_reserved set on a tail page (despite the head page not 1723ef5a22beSAndrea Arcangeli * having PG_reserved set). Enforcing this consistency between 1724ef5a22beSAndrea Arcangeli * head and tail pages allows drivers to optimize away a check 1725ef5a22beSAndrea Arcangeli * on the head page when they need know if put_page() is needed 1726ef5a22beSAndrea Arcangeli * after get_user_pages(). 1727ef5a22beSAndrea Arcangeli */ 1728ef5a22beSAndrea Arcangeli __ClearPageReserved(p); 17297118fc29SMike Kravetz /* 17307118fc29SMike Kravetz * Subtle and very unlikely 17317118fc29SMike Kravetz * 17327118fc29SMike Kravetz * Gigantic 'page allocators' such as memblock or cma will 17337118fc29SMike Kravetz * return a set of pages with each page ref counted. We need 17347118fc29SMike Kravetz * to turn this set of pages into a compound page with tail 17357118fc29SMike Kravetz * page ref counts set to zero. Code such as speculative page 17367118fc29SMike Kravetz * cache adding could take a ref on a 'to be' tail page. 17377118fc29SMike Kravetz * We need to respect any increased ref count, and only set 17387118fc29SMike Kravetz * the ref count to zero if count is currently 1. If count 1739416d85edSMike Kravetz * is not 1, we return an error. An error return indicates 1740416d85edSMike Kravetz * the set of pages can not be converted to a gigantic page. 1741416d85edSMike Kravetz * The caller who allocated the pages should then discard the 1742416d85edSMike Kravetz * pages using the appropriate free interface. 1743*34d9e35bSMike Kravetz * 1744*34d9e35bSMike Kravetz * In the case of demote, the ref count will be zero. 17457118fc29SMike Kravetz */ 1746*34d9e35bSMike Kravetz if (!demote) { 17477118fc29SMike Kravetz if (!page_ref_freeze(p, 1)) { 1748416d85edSMike Kravetz pr_warn("HugeTLB page can not be used due to unexpected inflated ref count\n"); 17497118fc29SMike Kravetz goto out_error; 17507118fc29SMike Kravetz } 1751*34d9e35bSMike Kravetz } else { 1752*34d9e35bSMike Kravetz VM_BUG_ON_PAGE(page_count(p), p); 1753*34d9e35bSMike Kravetz } 175458a84aa9SYouquan Song set_page_count(p, 0); 17551d798ca3SKirill A. Shutemov set_compound_head(p, page); 175620a0307cSWu Fengguang } 1757b4330afbSMike Kravetz atomic_set(compound_mapcount_ptr(page), -1); 175847e29d32SJohn Hubbard atomic_set(compound_pincount_ptr(page), 0); 17597118fc29SMike Kravetz return true; 17607118fc29SMike Kravetz 17617118fc29SMike Kravetz out_error: 17627118fc29SMike Kravetz /* undo tail page modifications made above */ 17637118fc29SMike Kravetz p = page + 1; 17647118fc29SMike Kravetz for (j = 1; j < i; j++, p = mem_map_next(p, page, j)) { 17657118fc29SMike Kravetz clear_compound_head(p); 17667118fc29SMike Kravetz set_page_refcounted(p); 17677118fc29SMike Kravetz } 17687118fc29SMike Kravetz /* need to clear PG_reserved on remaining tail pages */ 17697118fc29SMike Kravetz for (; j < nr_pages; j++, p = mem_map_next(p, page, j)) 17707118fc29SMike Kravetz __ClearPageReserved(p); 17717118fc29SMike Kravetz set_compound_order(page, 0); 17727118fc29SMike Kravetz page[1].compound_nr = 0; 17737118fc29SMike Kravetz __ClearPageHead(page); 17747118fc29SMike Kravetz return false; 177520a0307cSWu Fengguang } 177620a0307cSWu Fengguang 1777*34d9e35bSMike Kravetz static bool prep_compound_gigantic_page(struct page *page, unsigned int order) 1778*34d9e35bSMike Kravetz { 1779*34d9e35bSMike Kravetz return __prep_compound_gigantic_page(page, order, false); 1780*34d9e35bSMike Kravetz } 1781*34d9e35bSMike Kravetz 17827795912cSAndrew Morton /* 17837795912cSAndrew Morton * PageHuge() only returns true for hugetlbfs pages, but not for normal or 17847795912cSAndrew Morton * transparent huge pages. See the PageTransHuge() documentation for more 17857795912cSAndrew Morton * details. 17867795912cSAndrew Morton */ 178720a0307cSWu Fengguang int PageHuge(struct page *page) 178820a0307cSWu Fengguang { 178920a0307cSWu Fengguang if (!PageCompound(page)) 179020a0307cSWu Fengguang return 0; 179120a0307cSWu Fengguang 179220a0307cSWu Fengguang page = compound_head(page); 1793f1e61557SKirill A. Shutemov return page[1].compound_dtor == HUGETLB_PAGE_DTOR; 179420a0307cSWu Fengguang } 179543131e14SNaoya Horiguchi EXPORT_SYMBOL_GPL(PageHuge); 179643131e14SNaoya Horiguchi 179727c73ae7SAndrea Arcangeli /* 179827c73ae7SAndrea Arcangeli * PageHeadHuge() only returns true for hugetlbfs head page, but not for 179927c73ae7SAndrea Arcangeli * normal or transparent huge pages. 180027c73ae7SAndrea Arcangeli */ 180127c73ae7SAndrea Arcangeli int PageHeadHuge(struct page *page_head) 180227c73ae7SAndrea Arcangeli { 180327c73ae7SAndrea Arcangeli if (!PageHead(page_head)) 180427c73ae7SAndrea Arcangeli return 0; 180527c73ae7SAndrea Arcangeli 1806d4af73e3SVlastimil Babka return page_head[1].compound_dtor == HUGETLB_PAGE_DTOR; 180727c73ae7SAndrea Arcangeli } 180827c73ae7SAndrea Arcangeli 1809c0d0381aSMike Kravetz /* 1810c0d0381aSMike Kravetz * Find and lock address space (mapping) in write mode. 1811c0d0381aSMike Kravetz * 1812336bf30eSMike Kravetz * Upon entry, the page is locked which means that page_mapping() is 1813336bf30eSMike Kravetz * stable. Due to locking order, we can only trylock_write. If we can 1814336bf30eSMike Kravetz * not get the lock, simply return NULL to caller. 1815c0d0381aSMike Kravetz */ 1816c0d0381aSMike Kravetz struct address_space *hugetlb_page_mapping_lock_write(struct page *hpage) 1817c0d0381aSMike Kravetz { 1818336bf30eSMike Kravetz struct address_space *mapping = page_mapping(hpage); 1819c0d0381aSMike Kravetz 1820c0d0381aSMike Kravetz if (!mapping) 1821c0d0381aSMike Kravetz return mapping; 1822c0d0381aSMike Kravetz 1823c0d0381aSMike Kravetz if (i_mmap_trylock_write(mapping)) 1824c0d0381aSMike Kravetz return mapping; 1825c0d0381aSMike Kravetz 1826c0d0381aSMike Kravetz return NULL; 1827c0d0381aSMike Kravetz } 1828c0d0381aSMike Kravetz 1829fe19bd3dSHugh Dickins pgoff_t hugetlb_basepage_index(struct page *page) 183013d60f4bSZhang Yi { 183113d60f4bSZhang Yi struct page *page_head = compound_head(page); 183213d60f4bSZhang Yi pgoff_t index = page_index(page_head); 183313d60f4bSZhang Yi unsigned long compound_idx; 183413d60f4bSZhang Yi 183513d60f4bSZhang Yi if (compound_order(page_head) >= MAX_ORDER) 183613d60f4bSZhang Yi compound_idx = page_to_pfn(page) - page_to_pfn(page_head); 183713d60f4bSZhang Yi else 183813d60f4bSZhang Yi compound_idx = page - page_head; 183913d60f4bSZhang Yi 184013d60f4bSZhang Yi return (index << compound_order(page_head)) + compound_idx; 184113d60f4bSZhang Yi } 184213d60f4bSZhang Yi 18430c397daeSMichal Hocko static struct page *alloc_buddy_huge_page(struct hstate *h, 1844f60858f9SMike Kravetz gfp_t gfp_mask, int nid, nodemask_t *nmask, 1845f60858f9SMike Kravetz nodemask_t *node_alloc_noretry) 18461da177e4SLinus Torvalds { 1847af0fb9dfSMichal Hocko int order = huge_page_order(h); 18481da177e4SLinus Torvalds struct page *page; 1849f60858f9SMike Kravetz bool alloc_try_hard = true; 1850f96efd58SJoe Jin 1851f60858f9SMike Kravetz /* 1852f60858f9SMike Kravetz * By default we always try hard to allocate the page with 1853f60858f9SMike Kravetz * __GFP_RETRY_MAYFAIL flag. However, if we are allocating pages in 1854f60858f9SMike Kravetz * a loop (to adjust global huge page counts) and previous allocation 1855f60858f9SMike Kravetz * failed, do not continue to try hard on the same node. Use the 1856f60858f9SMike Kravetz * node_alloc_noretry bitmap to manage this state information. 1857f60858f9SMike Kravetz */ 1858f60858f9SMike Kravetz if (node_alloc_noretry && node_isset(nid, *node_alloc_noretry)) 1859f60858f9SMike Kravetz alloc_try_hard = false; 1860f60858f9SMike Kravetz gfp_mask |= __GFP_COMP|__GFP_NOWARN; 1861f60858f9SMike Kravetz if (alloc_try_hard) 1862f60858f9SMike Kravetz gfp_mask |= __GFP_RETRY_MAYFAIL; 1863af0fb9dfSMichal Hocko if (nid == NUMA_NO_NODE) 1864af0fb9dfSMichal Hocko nid = numa_mem_id(); 186584172f4bSMatthew Wilcox (Oracle) page = __alloc_pages(gfp_mask, order, nid, nmask); 1866af0fb9dfSMichal Hocko if (page) 1867af0fb9dfSMichal Hocko __count_vm_event(HTLB_BUDDY_PGALLOC); 1868af0fb9dfSMichal Hocko else 1869af0fb9dfSMichal Hocko __count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); 187063b4613cSNishanth Aravamudan 1871f60858f9SMike Kravetz /* 1872f60858f9SMike Kravetz * If we did not specify __GFP_RETRY_MAYFAIL, but still got a page this 1873f60858f9SMike Kravetz * indicates an overall state change. Clear bit so that we resume 1874f60858f9SMike Kravetz * normal 'try hard' allocations. 1875f60858f9SMike Kravetz */ 1876f60858f9SMike Kravetz if (node_alloc_noretry && page && !alloc_try_hard) 1877f60858f9SMike Kravetz node_clear(nid, *node_alloc_noretry); 1878f60858f9SMike Kravetz 1879f60858f9SMike Kravetz /* 1880f60858f9SMike Kravetz * If we tried hard to get a page but failed, set bit so that 1881f60858f9SMike Kravetz * subsequent attempts will not try as hard until there is an 1882f60858f9SMike Kravetz * overall state change. 1883f60858f9SMike Kravetz */ 1884f60858f9SMike Kravetz if (node_alloc_noretry && !page && alloc_try_hard) 1885f60858f9SMike Kravetz node_set(nid, *node_alloc_noretry); 1886f60858f9SMike Kravetz 188763b4613cSNishanth Aravamudan return page; 188863b4613cSNishanth Aravamudan } 188963b4613cSNishanth Aravamudan 1890af0fb9dfSMichal Hocko /* 18910c397daeSMichal Hocko * Common helper to allocate a fresh hugetlb page. All specific allocators 18920c397daeSMichal Hocko * should use this function to get new hugetlb pages 18930c397daeSMichal Hocko */ 18940c397daeSMichal Hocko static struct page *alloc_fresh_huge_page(struct hstate *h, 1895f60858f9SMike Kravetz gfp_t gfp_mask, int nid, nodemask_t *nmask, 1896f60858f9SMike Kravetz nodemask_t *node_alloc_noretry) 18970c397daeSMichal Hocko { 18980c397daeSMichal Hocko struct page *page; 18997118fc29SMike Kravetz bool retry = false; 19000c397daeSMichal Hocko 19017118fc29SMike Kravetz retry: 19020c397daeSMichal Hocko if (hstate_is_gigantic(h)) 19030c397daeSMichal Hocko page = alloc_gigantic_page(h, gfp_mask, nid, nmask); 19040c397daeSMichal Hocko else 19050c397daeSMichal Hocko page = alloc_buddy_huge_page(h, gfp_mask, 1906f60858f9SMike Kravetz nid, nmask, node_alloc_noretry); 19070c397daeSMichal Hocko if (!page) 19080c397daeSMichal Hocko return NULL; 19090c397daeSMichal Hocko 19107118fc29SMike Kravetz if (hstate_is_gigantic(h)) { 19117118fc29SMike Kravetz if (!prep_compound_gigantic_page(page, huge_page_order(h))) { 19127118fc29SMike Kravetz /* 19137118fc29SMike Kravetz * Rare failure to convert pages to compound page. 19147118fc29SMike Kravetz * Free pages and try again - ONCE! 19157118fc29SMike Kravetz */ 19167118fc29SMike Kravetz free_gigantic_page(page, huge_page_order(h)); 19177118fc29SMike Kravetz if (!retry) { 19187118fc29SMike Kravetz retry = true; 19197118fc29SMike Kravetz goto retry; 19207118fc29SMike Kravetz } 19217118fc29SMike Kravetz return NULL; 19227118fc29SMike Kravetz } 19237118fc29SMike Kravetz } 19240c397daeSMichal Hocko prep_new_huge_page(h, page, page_to_nid(page)); 19250c397daeSMichal Hocko 19260c397daeSMichal Hocko return page; 19270c397daeSMichal Hocko } 19280c397daeSMichal Hocko 19290c397daeSMichal Hocko /* 1930af0fb9dfSMichal Hocko * Allocates a fresh page to the hugetlb allocator pool in the node interleaved 1931af0fb9dfSMichal Hocko * manner. 1932af0fb9dfSMichal Hocko */ 1933f60858f9SMike Kravetz static int alloc_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed, 1934f60858f9SMike Kravetz nodemask_t *node_alloc_noretry) 1935b2261026SJoonsoo Kim { 1936b2261026SJoonsoo Kim struct page *page; 1937b2261026SJoonsoo Kim int nr_nodes, node; 1938af0fb9dfSMichal Hocko gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; 1939b2261026SJoonsoo Kim 1940b2261026SJoonsoo Kim for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { 1941f60858f9SMike Kravetz page = alloc_fresh_huge_page(h, gfp_mask, node, nodes_allowed, 1942f60858f9SMike Kravetz node_alloc_noretry); 1943af0fb9dfSMichal Hocko if (page) 1944b2261026SJoonsoo Kim break; 1945b2261026SJoonsoo Kim } 1946b2261026SJoonsoo Kim 1947af0fb9dfSMichal Hocko if (!page) 1948af0fb9dfSMichal Hocko return 0; 1949b2261026SJoonsoo Kim 1950af0fb9dfSMichal Hocko put_page(page); /* free it into the hugepage allocator */ 1951af0fb9dfSMichal Hocko 1952af0fb9dfSMichal Hocko return 1; 1953b2261026SJoonsoo Kim } 1954b2261026SJoonsoo Kim 1955e8c5c824SLee Schermerhorn /* 195610c6ec49SMike Kravetz * Remove huge page from pool from next node to free. Attempt to keep 195710c6ec49SMike Kravetz * persistent huge pages more or less balanced over allowed nodes. 195810c6ec49SMike Kravetz * This routine only 'removes' the hugetlb page. The caller must make 195910c6ec49SMike Kravetz * an additional call to free the page to low level allocators. 1960e8c5c824SLee Schermerhorn * Called with hugetlb_lock locked. 1961e8c5c824SLee Schermerhorn */ 196210c6ec49SMike Kravetz static struct page *remove_pool_huge_page(struct hstate *h, 196310c6ec49SMike Kravetz nodemask_t *nodes_allowed, 19646ae11b27SLee Schermerhorn bool acct_surplus) 1965e8c5c824SLee Schermerhorn { 1966b2261026SJoonsoo Kim int nr_nodes, node; 196710c6ec49SMike Kravetz struct page *page = NULL; 1968e8c5c824SLee Schermerhorn 19699487ca60SMike Kravetz lockdep_assert_held(&hugetlb_lock); 1970b2261026SJoonsoo Kim for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { 1971685f3457SLee Schermerhorn /* 1972685f3457SLee Schermerhorn * If we're returning unused surplus pages, only examine 1973685f3457SLee Schermerhorn * nodes with surplus pages. 1974685f3457SLee Schermerhorn */ 1975b2261026SJoonsoo Kim if ((!acct_surplus || h->surplus_huge_pages_node[node]) && 1976b2261026SJoonsoo Kim !list_empty(&h->hugepage_freelists[node])) { 197710c6ec49SMike Kravetz page = list_entry(h->hugepage_freelists[node].next, 1978e8c5c824SLee Schermerhorn struct page, lru); 19796eb4e88aSMike Kravetz remove_hugetlb_page(h, page, acct_surplus); 19809a76db09SLee Schermerhorn break; 1981e8c5c824SLee Schermerhorn } 1982b2261026SJoonsoo Kim } 1983e8c5c824SLee Schermerhorn 198410c6ec49SMike Kravetz return page; 1985e8c5c824SLee Schermerhorn } 1986e8c5c824SLee Schermerhorn 1987c8721bbbSNaoya Horiguchi /* 1988c8721bbbSNaoya Horiguchi * Dissolve a given free hugepage into free buddy pages. This function does 1989faf53defSNaoya Horiguchi * nothing for in-use hugepages and non-hugepages. 1990faf53defSNaoya Horiguchi * This function returns values like below: 1991faf53defSNaoya Horiguchi * 1992ad2fa371SMuchun Song * -ENOMEM: failed to allocate vmemmap pages to free the freed hugepages 1993ad2fa371SMuchun Song * when the system is under memory pressure and the feature of 1994ad2fa371SMuchun Song * freeing unused vmemmap pages associated with each hugetlb page 1995ad2fa371SMuchun Song * is enabled. 1996faf53defSNaoya Horiguchi * -EBUSY: failed to dissolved free hugepages or the hugepage is in-use 1997faf53defSNaoya Horiguchi * (allocated or reserved.) 1998faf53defSNaoya Horiguchi * 0: successfully dissolved free hugepages or the page is not a 1999faf53defSNaoya Horiguchi * hugepage (considered as already dissolved) 2000c8721bbbSNaoya Horiguchi */ 2001c3114a84SAnshuman Khandual int dissolve_free_huge_page(struct page *page) 2002c8721bbbSNaoya Horiguchi { 20036bc9b564SNaoya Horiguchi int rc = -EBUSY; 2004082d5b6bSGerald Schaefer 20057ffddd49SMuchun Song retry: 2006faf53defSNaoya Horiguchi /* Not to disrupt normal path by vainly holding hugetlb_lock */ 2007faf53defSNaoya Horiguchi if (!PageHuge(page)) 2008faf53defSNaoya Horiguchi return 0; 2009faf53defSNaoya Horiguchi 2010db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 2011faf53defSNaoya Horiguchi if (!PageHuge(page)) { 2012faf53defSNaoya Horiguchi rc = 0; 2013faf53defSNaoya Horiguchi goto out; 2014faf53defSNaoya Horiguchi } 2015faf53defSNaoya Horiguchi 2016faf53defSNaoya Horiguchi if (!page_count(page)) { 20172247bb33SGerald Schaefer struct page *head = compound_head(page); 20182247bb33SGerald Schaefer struct hstate *h = page_hstate(head); 20196bc9b564SNaoya Horiguchi if (h->free_huge_pages - h->resv_huge_pages == 0) 2020082d5b6bSGerald Schaefer goto out; 20217ffddd49SMuchun Song 20227ffddd49SMuchun Song /* 20237ffddd49SMuchun Song * We should make sure that the page is already on the free list 20247ffddd49SMuchun Song * when it is dissolved. 20257ffddd49SMuchun Song */ 20266c037149SMike Kravetz if (unlikely(!HPageFreed(head))) { 2027db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 20287ffddd49SMuchun Song cond_resched(); 20297ffddd49SMuchun Song 20307ffddd49SMuchun Song /* 20317ffddd49SMuchun Song * Theoretically, we should return -EBUSY when we 20327ffddd49SMuchun Song * encounter this race. In fact, we have a chance 20337ffddd49SMuchun Song * to successfully dissolve the page if we do a 20347ffddd49SMuchun Song * retry. Because the race window is quite small. 20357ffddd49SMuchun Song * If we seize this opportunity, it is an optimization 20367ffddd49SMuchun Song * for increasing the success rate of dissolving page. 20377ffddd49SMuchun Song */ 20387ffddd49SMuchun Song goto retry; 20397ffddd49SMuchun Song } 20407ffddd49SMuchun Song 2041ad2fa371SMuchun Song remove_hugetlb_page(h, head, false); 2042ad2fa371SMuchun Song h->max_huge_pages--; 2043ad2fa371SMuchun Song spin_unlock_irq(&hugetlb_lock); 2044ad2fa371SMuchun Song 2045c3114a84SAnshuman Khandual /* 2046ad2fa371SMuchun Song * Normally update_and_free_page will allocate required vmemmmap 2047ad2fa371SMuchun Song * before freeing the page. update_and_free_page will fail to 2048ad2fa371SMuchun Song * free the page if it can not allocate required vmemmap. We 2049ad2fa371SMuchun Song * need to adjust max_huge_pages if the page is not freed. 2050ad2fa371SMuchun Song * Attempt to allocate vmemmmap here so that we can take 2051ad2fa371SMuchun Song * appropriate action on failure. 2052ad2fa371SMuchun Song */ 2053ad2fa371SMuchun Song rc = alloc_huge_page_vmemmap(h, head); 2054ad2fa371SMuchun Song if (!rc) { 2055ad2fa371SMuchun Song /* 2056ad2fa371SMuchun Song * Move PageHWPoison flag from head page to the raw 2057ad2fa371SMuchun Song * error page, which makes any subpages rather than 2058ad2fa371SMuchun Song * the error page reusable. 2059c3114a84SAnshuman Khandual */ 2060c3114a84SAnshuman Khandual if (PageHWPoison(head) && page != head) { 2061c3114a84SAnshuman Khandual SetPageHWPoison(page); 2062c3114a84SAnshuman Khandual ClearPageHWPoison(head); 2063c3114a84SAnshuman Khandual } 2064b65d4adbSMuchun Song update_and_free_page(h, head, false); 2065ad2fa371SMuchun Song } else { 2066ad2fa371SMuchun Song spin_lock_irq(&hugetlb_lock); 2067ad2fa371SMuchun Song add_hugetlb_page(h, head, false); 2068ad2fa371SMuchun Song h->max_huge_pages++; 2069ad2fa371SMuchun Song spin_unlock_irq(&hugetlb_lock); 2070ad2fa371SMuchun Song } 2071ad2fa371SMuchun Song 2072ad2fa371SMuchun Song return rc; 2073c8721bbbSNaoya Horiguchi } 2074082d5b6bSGerald Schaefer out: 2075db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 2076082d5b6bSGerald Schaefer return rc; 2077c8721bbbSNaoya Horiguchi } 2078c8721bbbSNaoya Horiguchi 2079c8721bbbSNaoya Horiguchi /* 2080c8721bbbSNaoya Horiguchi * Dissolve free hugepages in a given pfn range. Used by memory hotplug to 2081c8721bbbSNaoya Horiguchi * make specified memory blocks removable from the system. 20822247bb33SGerald Schaefer * Note that this will dissolve a free gigantic hugepage completely, if any 20832247bb33SGerald Schaefer * part of it lies within the given range. 2084082d5b6bSGerald Schaefer * Also note that if dissolve_free_huge_page() returns with an error, all 2085082d5b6bSGerald Schaefer * free hugepages that were dissolved before that error are lost. 2086c8721bbbSNaoya Horiguchi */ 2087082d5b6bSGerald Schaefer int dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn) 2088c8721bbbSNaoya Horiguchi { 2089c8721bbbSNaoya Horiguchi unsigned long pfn; 2090eb03aa00SGerald Schaefer struct page *page; 2091082d5b6bSGerald Schaefer int rc = 0; 2092c8721bbbSNaoya Horiguchi 2093d0177639SLi Zhong if (!hugepages_supported()) 2094082d5b6bSGerald Schaefer return rc; 2095d0177639SLi Zhong 2096eb03aa00SGerald Schaefer for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << minimum_order) { 2097eb03aa00SGerald Schaefer page = pfn_to_page(pfn); 2098eb03aa00SGerald Schaefer rc = dissolve_free_huge_page(page); 2099eb03aa00SGerald Schaefer if (rc) 2100082d5b6bSGerald Schaefer break; 2101eb03aa00SGerald Schaefer } 2102082d5b6bSGerald Schaefer 2103082d5b6bSGerald Schaefer return rc; 2104c8721bbbSNaoya Horiguchi } 2105c8721bbbSNaoya Horiguchi 2106ab5ac90aSMichal Hocko /* 2107ab5ac90aSMichal Hocko * Allocates a fresh surplus page from the page allocator. 2108ab5ac90aSMichal Hocko */ 21090c397daeSMichal Hocko static struct page *alloc_surplus_huge_page(struct hstate *h, gfp_t gfp_mask, 2110b65a4edaSMike Kravetz int nid, nodemask_t *nmask, bool zero_ref) 21117893d1d5SAdam Litke { 21129980d744SMichal Hocko struct page *page = NULL; 2113b65a4edaSMike Kravetz bool retry = false; 21147893d1d5SAdam Litke 2115bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 2116aa888a74SAndi Kleen return NULL; 2117aa888a74SAndi Kleen 2118db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 21199980d744SMichal Hocko if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) 21209980d744SMichal Hocko goto out_unlock; 2121db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 2122d1c3fb1fSNishanth Aravamudan 2123b65a4edaSMike Kravetz retry: 2124f60858f9SMike Kravetz page = alloc_fresh_huge_page(h, gfp_mask, nid, nmask, NULL); 21259980d744SMichal Hocko if (!page) 21260c397daeSMichal Hocko return NULL; 2127d1c3fb1fSNishanth Aravamudan 2128db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 21299980d744SMichal Hocko /* 21309980d744SMichal Hocko * We could have raced with the pool size change. 21319980d744SMichal Hocko * Double check that and simply deallocate the new page 21329980d744SMichal Hocko * if we would end up overcommiting the surpluses. Abuse 21339980d744SMichal Hocko * temporary page to workaround the nasty free_huge_page 21349980d744SMichal Hocko * codeflow 21359980d744SMichal Hocko */ 21369980d744SMichal Hocko if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) { 21379157c311SMike Kravetz SetHPageTemporary(page); 2138db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 21399980d744SMichal Hocko put_page(page); 21402bf753e6SKai Shen return NULL; 2141b65a4edaSMike Kravetz } 2142b65a4edaSMike Kravetz 2143b65a4edaSMike Kravetz if (zero_ref) { 2144b65a4edaSMike Kravetz /* 2145b65a4edaSMike Kravetz * Caller requires a page with zero ref count. 2146b65a4edaSMike Kravetz * We will drop ref count here. If someone else is holding 2147b65a4edaSMike Kravetz * a ref, the page will be freed when they drop it. Abuse 2148b65a4edaSMike Kravetz * temporary page flag to accomplish this. 2149b65a4edaSMike Kravetz */ 2150b65a4edaSMike Kravetz SetHPageTemporary(page); 2151b65a4edaSMike Kravetz if (!put_page_testzero(page)) { 2152b65a4edaSMike Kravetz /* 2153b65a4edaSMike Kravetz * Unexpected inflated ref count on freshly allocated 2154b65a4edaSMike Kravetz * huge. Retry once. 2155b65a4edaSMike Kravetz */ 2156b65a4edaSMike Kravetz pr_info("HugeTLB unexpected inflated ref count on freshly allocated page\n"); 2157b65a4edaSMike Kravetz spin_unlock_irq(&hugetlb_lock); 2158b65a4edaSMike Kravetz if (retry) 2159b65a4edaSMike Kravetz return NULL; 2160b65a4edaSMike Kravetz 2161b65a4edaSMike Kravetz retry = true; 2162b65a4edaSMike Kravetz goto retry; 2163b65a4edaSMike Kravetz } 2164b65a4edaSMike Kravetz ClearHPageTemporary(page); 2165b65a4edaSMike Kravetz } 2166b65a4edaSMike Kravetz 21679980d744SMichal Hocko h->surplus_huge_pages++; 21684704dea3SMichal Hocko h->surplus_huge_pages_node[page_to_nid(page)]++; 21699980d744SMichal Hocko 21709980d744SMichal Hocko out_unlock: 2171db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 21727893d1d5SAdam Litke 21737893d1d5SAdam Litke return page; 21747893d1d5SAdam Litke } 21757893d1d5SAdam Litke 2176bbe88753SJoonsoo Kim static struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask, 2177ab5ac90aSMichal Hocko int nid, nodemask_t *nmask) 2178ab5ac90aSMichal Hocko { 2179ab5ac90aSMichal Hocko struct page *page; 2180ab5ac90aSMichal Hocko 2181ab5ac90aSMichal Hocko if (hstate_is_gigantic(h)) 2182ab5ac90aSMichal Hocko return NULL; 2183ab5ac90aSMichal Hocko 2184f60858f9SMike Kravetz page = alloc_fresh_huge_page(h, gfp_mask, nid, nmask, NULL); 2185ab5ac90aSMichal Hocko if (!page) 2186ab5ac90aSMichal Hocko return NULL; 2187ab5ac90aSMichal Hocko 2188ab5ac90aSMichal Hocko /* 2189ab5ac90aSMichal Hocko * We do not account these pages as surplus because they are only 2190ab5ac90aSMichal Hocko * temporary and will be released properly on the last reference 2191ab5ac90aSMichal Hocko */ 21929157c311SMike Kravetz SetHPageTemporary(page); 2193ab5ac90aSMichal Hocko 2194ab5ac90aSMichal Hocko return page; 2195ab5ac90aSMichal Hocko } 2196ab5ac90aSMichal Hocko 2197e4e574b7SAdam Litke /* 2198099730d6SDave Hansen * Use the VMA's mpolicy to allocate a huge page from the buddy. 2199099730d6SDave Hansen */ 2200e0ec90eeSDave Hansen static 22010c397daeSMichal Hocko struct page *alloc_buddy_huge_page_with_mpol(struct hstate *h, 2202099730d6SDave Hansen struct vm_area_struct *vma, unsigned long addr) 2203099730d6SDave Hansen { 2204cfcaa66fSBen Widawsky struct page *page = NULL; 2205aaf14e40SMichal Hocko struct mempolicy *mpol; 2206aaf14e40SMichal Hocko gfp_t gfp_mask = htlb_alloc_mask(h); 2207aaf14e40SMichal Hocko int nid; 2208aaf14e40SMichal Hocko nodemask_t *nodemask; 2209aaf14e40SMichal Hocko 2210aaf14e40SMichal Hocko nid = huge_node(vma, addr, gfp_mask, &mpol, &nodemask); 2211cfcaa66fSBen Widawsky if (mpol_is_preferred_many(mpol)) { 2212cfcaa66fSBen Widawsky gfp_t gfp = gfp_mask | __GFP_NOWARN; 2213cfcaa66fSBen Widawsky 2214cfcaa66fSBen Widawsky gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL); 2215cfcaa66fSBen Widawsky page = alloc_surplus_huge_page(h, gfp, nid, nodemask, false); 2216cfcaa66fSBen Widawsky 2217cfcaa66fSBen Widawsky /* Fallback to all nodes if page==NULL */ 2218cfcaa66fSBen Widawsky nodemask = NULL; 2219cfcaa66fSBen Widawsky } 2220cfcaa66fSBen Widawsky 2221cfcaa66fSBen Widawsky if (!page) 2222b65a4edaSMike Kravetz page = alloc_surplus_huge_page(h, gfp_mask, nid, nodemask, false); 2223aaf14e40SMichal Hocko mpol_cond_put(mpol); 2224aaf14e40SMichal Hocko return page; 2225099730d6SDave Hansen } 2226099730d6SDave Hansen 2227ab5ac90aSMichal Hocko /* page migration callback function */ 22283e59fcb0SMichal Hocko struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid, 2229d92bbc27SJoonsoo Kim nodemask_t *nmask, gfp_t gfp_mask) 22304db9b2efSMichal Hocko { 2231db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 22324db9b2efSMichal Hocko if (h->free_huge_pages - h->resv_huge_pages > 0) { 22333e59fcb0SMichal Hocko struct page *page; 22343e59fcb0SMichal Hocko 22353e59fcb0SMichal Hocko page = dequeue_huge_page_nodemask(h, gfp_mask, preferred_nid, nmask); 22363e59fcb0SMichal Hocko if (page) { 2237db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 22383e59fcb0SMichal Hocko return page; 22394db9b2efSMichal Hocko } 22404db9b2efSMichal Hocko } 2241db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 22424db9b2efSMichal Hocko 22430c397daeSMichal Hocko return alloc_migrate_huge_page(h, gfp_mask, preferred_nid, nmask); 22444db9b2efSMichal Hocko } 22454db9b2efSMichal Hocko 2246ebd63723SMichal Hocko /* mempolicy aware migration callback */ 2247389c8178SMichal Hocko struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma, 2248389c8178SMichal Hocko unsigned long address) 2249ebd63723SMichal Hocko { 2250ebd63723SMichal Hocko struct mempolicy *mpol; 2251ebd63723SMichal Hocko nodemask_t *nodemask; 2252ebd63723SMichal Hocko struct page *page; 2253ebd63723SMichal Hocko gfp_t gfp_mask; 2254ebd63723SMichal Hocko int node; 2255ebd63723SMichal Hocko 2256ebd63723SMichal Hocko gfp_mask = htlb_alloc_mask(h); 2257ebd63723SMichal Hocko node = huge_node(vma, address, gfp_mask, &mpol, &nodemask); 2258d92bbc27SJoonsoo Kim page = alloc_huge_page_nodemask(h, node, nodemask, gfp_mask); 2259ebd63723SMichal Hocko mpol_cond_put(mpol); 2260ebd63723SMichal Hocko 2261ebd63723SMichal Hocko return page; 2262ebd63723SMichal Hocko } 2263ebd63723SMichal Hocko 2264bf50bab2SNaoya Horiguchi /* 226525985edcSLucas De Marchi * Increase the hugetlb pool such that it can accommodate a reservation 2266e4e574b7SAdam Litke * of size 'delta'. 2267e4e574b7SAdam Litke */ 22680a4f3d1bSLiu Xiang static int gather_surplus_pages(struct hstate *h, long delta) 22691b2a1e7bSJules Irenge __must_hold(&hugetlb_lock) 2270e4e574b7SAdam Litke { 2271e4e574b7SAdam Litke struct list_head surplus_list; 2272e4e574b7SAdam Litke struct page *page, *tmp; 22730a4f3d1bSLiu Xiang int ret; 22740a4f3d1bSLiu Xiang long i; 22750a4f3d1bSLiu Xiang long needed, allocated; 227628073b02SHillf Danton bool alloc_ok = true; 2277e4e574b7SAdam Litke 22789487ca60SMike Kravetz lockdep_assert_held(&hugetlb_lock); 2279a5516438SAndi Kleen needed = (h->resv_huge_pages + delta) - h->free_huge_pages; 2280ac09b3a1SAdam Litke if (needed <= 0) { 2281a5516438SAndi Kleen h->resv_huge_pages += delta; 2282e4e574b7SAdam Litke return 0; 2283ac09b3a1SAdam Litke } 2284e4e574b7SAdam Litke 2285e4e574b7SAdam Litke allocated = 0; 2286e4e574b7SAdam Litke INIT_LIST_HEAD(&surplus_list); 2287e4e574b7SAdam Litke 2288e4e574b7SAdam Litke ret = -ENOMEM; 2289e4e574b7SAdam Litke retry: 2290db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 2291e4e574b7SAdam Litke for (i = 0; i < needed; i++) { 22920c397daeSMichal Hocko page = alloc_surplus_huge_page(h, htlb_alloc_mask(h), 2293b65a4edaSMike Kravetz NUMA_NO_NODE, NULL, true); 229428073b02SHillf Danton if (!page) { 229528073b02SHillf Danton alloc_ok = false; 229628073b02SHillf Danton break; 229728073b02SHillf Danton } 2298e4e574b7SAdam Litke list_add(&page->lru, &surplus_list); 229969ed779aSDavid Rientjes cond_resched(); 2300e4e574b7SAdam Litke } 230128073b02SHillf Danton allocated += i; 2302e4e574b7SAdam Litke 2303e4e574b7SAdam Litke /* 2304e4e574b7SAdam Litke * After retaking hugetlb_lock, we need to recalculate 'needed' 2305e4e574b7SAdam Litke * because either resv_huge_pages or free_huge_pages may have changed. 2306e4e574b7SAdam Litke */ 2307db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 2308a5516438SAndi Kleen needed = (h->resv_huge_pages + delta) - 2309a5516438SAndi Kleen (h->free_huge_pages + allocated); 231028073b02SHillf Danton if (needed > 0) { 231128073b02SHillf Danton if (alloc_ok) 2312e4e574b7SAdam Litke goto retry; 231328073b02SHillf Danton /* 231428073b02SHillf Danton * We were not able to allocate enough pages to 231528073b02SHillf Danton * satisfy the entire reservation so we free what 231628073b02SHillf Danton * we've allocated so far. 231728073b02SHillf Danton */ 231828073b02SHillf Danton goto free; 231928073b02SHillf Danton } 2320e4e574b7SAdam Litke /* 2321e4e574b7SAdam Litke * The surplus_list now contains _at_least_ the number of extra pages 232225985edcSLucas De Marchi * needed to accommodate the reservation. Add the appropriate number 2323e4e574b7SAdam Litke * of pages to the hugetlb pool and free the extras back to the buddy 2324ac09b3a1SAdam Litke * allocator. Commit the entire reservation here to prevent another 2325ac09b3a1SAdam Litke * process from stealing the pages as they are added to the pool but 2326ac09b3a1SAdam Litke * before they are reserved. 2327e4e574b7SAdam Litke */ 2328e4e574b7SAdam Litke needed += allocated; 2329a5516438SAndi Kleen h->resv_huge_pages += delta; 2330e4e574b7SAdam Litke ret = 0; 2331a9869b83SNaoya Horiguchi 233219fc3f0aSAdam Litke /* Free the needed pages to the hugetlb pool */ 233319fc3f0aSAdam Litke list_for_each_entry_safe(page, tmp, &surplus_list, lru) { 233419fc3f0aSAdam Litke if ((--needed) < 0) 233519fc3f0aSAdam Litke break; 2336b65a4edaSMike Kravetz /* Add the page to the hugetlb allocator */ 2337a5516438SAndi Kleen enqueue_huge_page(h, page); 233819fc3f0aSAdam Litke } 233928073b02SHillf Danton free: 2340db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 234119fc3f0aSAdam Litke 2342b65a4edaSMike Kravetz /* 2343b65a4edaSMike Kravetz * Free unnecessary surplus pages to the buddy allocator. 2344b65a4edaSMike Kravetz * Pages have no ref count, call free_huge_page directly. 2345b65a4edaSMike Kravetz */ 2346c0d934baSJoonsoo Kim list_for_each_entry_safe(page, tmp, &surplus_list, lru) 2347b65a4edaSMike Kravetz free_huge_page(page); 2348db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 2349e4e574b7SAdam Litke 2350e4e574b7SAdam Litke return ret; 2351e4e574b7SAdam Litke } 2352e4e574b7SAdam Litke 2353e4e574b7SAdam Litke /* 2354e5bbc8a6SMike Kravetz * This routine has two main purposes: 2355e5bbc8a6SMike Kravetz * 1) Decrement the reservation count (resv_huge_pages) by the value passed 2356e5bbc8a6SMike Kravetz * in unused_resv_pages. This corresponds to the prior adjustments made 2357e5bbc8a6SMike Kravetz * to the associated reservation map. 2358e5bbc8a6SMike Kravetz * 2) Free any unused surplus pages that may have been allocated to satisfy 2359e5bbc8a6SMike Kravetz * the reservation. As many as unused_resv_pages may be freed. 2360e4e574b7SAdam Litke */ 2361a5516438SAndi Kleen static void return_unused_surplus_pages(struct hstate *h, 2362a5516438SAndi Kleen unsigned long unused_resv_pages) 2363e4e574b7SAdam Litke { 2364e4e574b7SAdam Litke unsigned long nr_pages; 236510c6ec49SMike Kravetz struct page *page; 236610c6ec49SMike Kravetz LIST_HEAD(page_list); 236710c6ec49SMike Kravetz 23689487ca60SMike Kravetz lockdep_assert_held(&hugetlb_lock); 236910c6ec49SMike Kravetz /* Uncommit the reservation */ 237010c6ec49SMike Kravetz h->resv_huge_pages -= unused_resv_pages; 2371e4e574b7SAdam Litke 2372aa888a74SAndi Kleen /* Cannot return gigantic pages currently */ 2373bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 2374e5bbc8a6SMike Kravetz goto out; 2375aa888a74SAndi Kleen 2376e5bbc8a6SMike Kravetz /* 2377e5bbc8a6SMike Kravetz * Part (or even all) of the reservation could have been backed 2378e5bbc8a6SMike Kravetz * by pre-allocated pages. Only free surplus pages. 2379e5bbc8a6SMike Kravetz */ 2380a5516438SAndi Kleen nr_pages = min(unused_resv_pages, h->surplus_huge_pages); 2381e4e574b7SAdam Litke 2382685f3457SLee Schermerhorn /* 2383685f3457SLee Schermerhorn * We want to release as many surplus pages as possible, spread 23849b5e5d0fSLee Schermerhorn * evenly across all nodes with memory. Iterate across these nodes 23859b5e5d0fSLee Schermerhorn * until we can no longer free unreserved surplus pages. This occurs 23869b5e5d0fSLee Schermerhorn * when the nodes with surplus pages have no free pages. 238710c6ec49SMike Kravetz * remove_pool_huge_page() will balance the freed pages across the 23889b5e5d0fSLee Schermerhorn * on-line nodes with memory and will handle the hstate accounting. 2389685f3457SLee Schermerhorn */ 2390685f3457SLee Schermerhorn while (nr_pages--) { 239110c6ec49SMike Kravetz page = remove_pool_huge_page(h, &node_states[N_MEMORY], 1); 239210c6ec49SMike Kravetz if (!page) 2393e5bbc8a6SMike Kravetz goto out; 239410c6ec49SMike Kravetz 239510c6ec49SMike Kravetz list_add(&page->lru, &page_list); 2396e4e574b7SAdam Litke } 2397e5bbc8a6SMike Kravetz 2398e5bbc8a6SMike Kravetz out: 2399db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 240010c6ec49SMike Kravetz update_and_free_pages_bulk(h, &page_list); 2401db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 2402e4e574b7SAdam Litke } 2403e4e574b7SAdam Litke 24045e911373SMike Kravetz 2405c37f9fb1SAndy Whitcroft /* 2406feba16e2SMike Kravetz * vma_needs_reservation, vma_commit_reservation and vma_end_reservation 24075e911373SMike Kravetz * are used by the huge page allocation routines to manage reservations. 2408cf3ad20bSMike Kravetz * 2409cf3ad20bSMike Kravetz * vma_needs_reservation is called to determine if the huge page at addr 2410cf3ad20bSMike Kravetz * within the vma has an associated reservation. If a reservation is 2411cf3ad20bSMike Kravetz * needed, the value 1 is returned. The caller is then responsible for 2412cf3ad20bSMike Kravetz * managing the global reservation and subpool usage counts. After 2413cf3ad20bSMike Kravetz * the huge page has been allocated, vma_commit_reservation is called 2414feba16e2SMike Kravetz * to add the page to the reservation map. If the page allocation fails, 2415feba16e2SMike Kravetz * the reservation must be ended instead of committed. vma_end_reservation 2416feba16e2SMike Kravetz * is called in such cases. 2417cf3ad20bSMike Kravetz * 2418cf3ad20bSMike Kravetz * In the normal case, vma_commit_reservation returns the same value 2419cf3ad20bSMike Kravetz * as the preceding vma_needs_reservation call. The only time this 2420cf3ad20bSMike Kravetz * is not the case is if a reserve map was changed between calls. It 2421cf3ad20bSMike Kravetz * is the responsibility of the caller to notice the difference and 2422cf3ad20bSMike Kravetz * take appropriate action. 242396b96a96SMike Kravetz * 242496b96a96SMike Kravetz * vma_add_reservation is used in error paths where a reservation must 242596b96a96SMike Kravetz * be restored when a newly allocated huge page must be freed. It is 242696b96a96SMike Kravetz * to be called after calling vma_needs_reservation to determine if a 242796b96a96SMike Kravetz * reservation exists. 2428846be085SMike Kravetz * 2429846be085SMike Kravetz * vma_del_reservation is used in error paths where an entry in the reserve 2430846be085SMike Kravetz * map was created during huge page allocation and must be removed. It is to 2431846be085SMike Kravetz * be called after calling vma_needs_reservation to determine if a reservation 2432846be085SMike Kravetz * exists. 2433c37f9fb1SAndy Whitcroft */ 24345e911373SMike Kravetz enum vma_resv_mode { 24355e911373SMike Kravetz VMA_NEEDS_RESV, 24365e911373SMike Kravetz VMA_COMMIT_RESV, 2437feba16e2SMike Kravetz VMA_END_RESV, 243896b96a96SMike Kravetz VMA_ADD_RESV, 2439846be085SMike Kravetz VMA_DEL_RESV, 24405e911373SMike Kravetz }; 2441cf3ad20bSMike Kravetz static long __vma_reservation_common(struct hstate *h, 2442cf3ad20bSMike Kravetz struct vm_area_struct *vma, unsigned long addr, 24435e911373SMike Kravetz enum vma_resv_mode mode) 2444c37f9fb1SAndy Whitcroft { 24454e35f483SJoonsoo Kim struct resv_map *resv; 24464e35f483SJoonsoo Kim pgoff_t idx; 2447cf3ad20bSMike Kravetz long ret; 24480db9d74eSMina Almasry long dummy_out_regions_needed; 2449c37f9fb1SAndy Whitcroft 24504e35f483SJoonsoo Kim resv = vma_resv_map(vma); 24514e35f483SJoonsoo Kim if (!resv) 2452c37f9fb1SAndy Whitcroft return 1; 2453c37f9fb1SAndy Whitcroft 24544e35f483SJoonsoo Kim idx = vma_hugecache_offset(h, vma, addr); 24555e911373SMike Kravetz switch (mode) { 24565e911373SMike Kravetz case VMA_NEEDS_RESV: 24570db9d74eSMina Almasry ret = region_chg(resv, idx, idx + 1, &dummy_out_regions_needed); 24580db9d74eSMina Almasry /* We assume that vma_reservation_* routines always operate on 24590db9d74eSMina Almasry * 1 page, and that adding to resv map a 1 page entry can only 24600db9d74eSMina Almasry * ever require 1 region. 24610db9d74eSMina Almasry */ 24620db9d74eSMina Almasry VM_BUG_ON(dummy_out_regions_needed != 1); 24635e911373SMike Kravetz break; 24645e911373SMike Kravetz case VMA_COMMIT_RESV: 2465075a61d0SMina Almasry ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); 24660db9d74eSMina Almasry /* region_add calls of range 1 should never fail. */ 24670db9d74eSMina Almasry VM_BUG_ON(ret < 0); 24685e911373SMike Kravetz break; 2469feba16e2SMike Kravetz case VMA_END_RESV: 24700db9d74eSMina Almasry region_abort(resv, idx, idx + 1, 1); 24715e911373SMike Kravetz ret = 0; 24725e911373SMike Kravetz break; 247396b96a96SMike Kravetz case VMA_ADD_RESV: 24740db9d74eSMina Almasry if (vma->vm_flags & VM_MAYSHARE) { 2475075a61d0SMina Almasry ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); 24760db9d74eSMina Almasry /* region_add calls of range 1 should never fail. */ 24770db9d74eSMina Almasry VM_BUG_ON(ret < 0); 24780db9d74eSMina Almasry } else { 24790db9d74eSMina Almasry region_abort(resv, idx, idx + 1, 1); 248096b96a96SMike Kravetz ret = region_del(resv, idx, idx + 1); 248196b96a96SMike Kravetz } 248296b96a96SMike Kravetz break; 2483846be085SMike Kravetz case VMA_DEL_RESV: 2484846be085SMike Kravetz if (vma->vm_flags & VM_MAYSHARE) { 2485846be085SMike Kravetz region_abort(resv, idx, idx + 1, 1); 2486846be085SMike Kravetz ret = region_del(resv, idx, idx + 1); 2487846be085SMike Kravetz } else { 2488846be085SMike Kravetz ret = region_add(resv, idx, idx + 1, 1, NULL, NULL); 2489846be085SMike Kravetz /* region_add calls of range 1 should never fail. */ 2490846be085SMike Kravetz VM_BUG_ON(ret < 0); 2491846be085SMike Kravetz } 2492846be085SMike Kravetz break; 24935e911373SMike Kravetz default: 24945e911373SMike Kravetz BUG(); 24955e911373SMike Kravetz } 249684afd99bSAndy Whitcroft 2497846be085SMike Kravetz if (vma->vm_flags & VM_MAYSHARE || mode == VMA_DEL_RESV) 2498cf3ad20bSMike Kravetz return ret; 249967961f9dSMike Kravetz /* 2500bf3d12b9SMiaohe Lin * We know private mapping must have HPAGE_RESV_OWNER set. 2501bf3d12b9SMiaohe Lin * 250267961f9dSMike Kravetz * In most cases, reserves always exist for private mappings. 250367961f9dSMike Kravetz * However, a file associated with mapping could have been 250467961f9dSMike Kravetz * hole punched or truncated after reserves were consumed. 250567961f9dSMike Kravetz * As subsequent fault on such a range will not use reserves. 250667961f9dSMike Kravetz * Subtle - The reserve map for private mappings has the 250767961f9dSMike Kravetz * opposite meaning than that of shared mappings. If NO 250867961f9dSMike Kravetz * entry is in the reserve map, it means a reservation exists. 250967961f9dSMike Kravetz * If an entry exists in the reserve map, it means the 251067961f9dSMike Kravetz * reservation has already been consumed. As a result, the 251167961f9dSMike Kravetz * return value of this routine is the opposite of the 251267961f9dSMike Kravetz * value returned from reserve map manipulation routines above. 251367961f9dSMike Kravetz */ 2514bf3d12b9SMiaohe Lin if (ret > 0) 251567961f9dSMike Kravetz return 0; 2516bf3d12b9SMiaohe Lin if (ret == 0) 251767961f9dSMike Kravetz return 1; 2518bf3d12b9SMiaohe Lin return ret; 251984afd99bSAndy Whitcroft } 2520cf3ad20bSMike Kravetz 2521cf3ad20bSMike Kravetz static long vma_needs_reservation(struct hstate *h, 2522a5516438SAndi Kleen struct vm_area_struct *vma, unsigned long addr) 2523c37f9fb1SAndy Whitcroft { 25245e911373SMike Kravetz return __vma_reservation_common(h, vma, addr, VMA_NEEDS_RESV); 2525cf3ad20bSMike Kravetz } 2526c37f9fb1SAndy Whitcroft 2527cf3ad20bSMike Kravetz static long vma_commit_reservation(struct hstate *h, 2528cf3ad20bSMike Kravetz struct vm_area_struct *vma, unsigned long addr) 2529cf3ad20bSMike Kravetz { 25305e911373SMike Kravetz return __vma_reservation_common(h, vma, addr, VMA_COMMIT_RESV); 25315e911373SMike Kravetz } 25325e911373SMike Kravetz 2533feba16e2SMike Kravetz static void vma_end_reservation(struct hstate *h, 25345e911373SMike Kravetz struct vm_area_struct *vma, unsigned long addr) 25355e911373SMike Kravetz { 2536feba16e2SMike Kravetz (void)__vma_reservation_common(h, vma, addr, VMA_END_RESV); 2537c37f9fb1SAndy Whitcroft } 2538c37f9fb1SAndy Whitcroft 253996b96a96SMike Kravetz static long vma_add_reservation(struct hstate *h, 254096b96a96SMike Kravetz struct vm_area_struct *vma, unsigned long addr) 254196b96a96SMike Kravetz { 254296b96a96SMike Kravetz return __vma_reservation_common(h, vma, addr, VMA_ADD_RESV); 254396b96a96SMike Kravetz } 254496b96a96SMike Kravetz 2545846be085SMike Kravetz static long vma_del_reservation(struct hstate *h, 2546846be085SMike Kravetz struct vm_area_struct *vma, unsigned long addr) 254796b96a96SMike Kravetz { 2548846be085SMike Kravetz return __vma_reservation_common(h, vma, addr, VMA_DEL_RESV); 2549846be085SMike Kravetz } 2550846be085SMike Kravetz 2551846be085SMike Kravetz /* 2552846be085SMike Kravetz * This routine is called to restore reservation information on error paths. 2553846be085SMike Kravetz * It should ONLY be called for pages allocated via alloc_huge_page(), and 2554846be085SMike Kravetz * the hugetlb mutex should remain held when calling this routine. 2555846be085SMike Kravetz * 2556846be085SMike Kravetz * It handles two specific cases: 2557846be085SMike Kravetz * 1) A reservation was in place and the page consumed the reservation. 2558846be085SMike Kravetz * HPageRestoreReserve is set in the page. 2559846be085SMike Kravetz * 2) No reservation was in place for the page, so HPageRestoreReserve is 2560846be085SMike Kravetz * not set. However, alloc_huge_page always updates the reserve map. 2561846be085SMike Kravetz * 2562846be085SMike Kravetz * In case 1, free_huge_page later in the error path will increment the 2563846be085SMike Kravetz * global reserve count. But, free_huge_page does not have enough context 2564846be085SMike Kravetz * to adjust the reservation map. This case deals primarily with private 2565846be085SMike Kravetz * mappings. Adjust the reserve map here to be consistent with global 2566846be085SMike Kravetz * reserve count adjustments to be made by free_huge_page. Make sure the 2567846be085SMike Kravetz * reserve map indicates there is a reservation present. 2568846be085SMike Kravetz * 2569846be085SMike Kravetz * In case 2, simply undo reserve map modifications done by alloc_huge_page. 2570846be085SMike Kravetz */ 2571846be085SMike Kravetz void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma, 2572846be085SMike Kravetz unsigned long address, struct page *page) 2573846be085SMike Kravetz { 257496b96a96SMike Kravetz long rc = vma_needs_reservation(h, vma, address); 257596b96a96SMike Kravetz 2576846be085SMike Kravetz if (HPageRestoreReserve(page)) { 2577846be085SMike Kravetz if (unlikely(rc < 0)) 257896b96a96SMike Kravetz /* 257996b96a96SMike Kravetz * Rare out of memory condition in reserve map 2580d6995da3SMike Kravetz * manipulation. Clear HPageRestoreReserve so that 258196b96a96SMike Kravetz * global reserve count will not be incremented 258296b96a96SMike Kravetz * by free_huge_page. This will make it appear 258396b96a96SMike Kravetz * as though the reservation for this page was 258496b96a96SMike Kravetz * consumed. This may prevent the task from 258596b96a96SMike Kravetz * faulting in the page at a later time. This 258696b96a96SMike Kravetz * is better than inconsistent global huge page 258796b96a96SMike Kravetz * accounting of reserve counts. 258896b96a96SMike Kravetz */ 2589d6995da3SMike Kravetz ClearHPageRestoreReserve(page); 2590846be085SMike Kravetz else if (rc) 2591846be085SMike Kravetz (void)vma_add_reservation(h, vma, address); 2592846be085SMike Kravetz else 2593846be085SMike Kravetz vma_end_reservation(h, vma, address); 2594846be085SMike Kravetz } else { 2595846be085SMike Kravetz if (!rc) { 259696b96a96SMike Kravetz /* 2597846be085SMike Kravetz * This indicates there is an entry in the reserve map 2598c7b1850dSMike Kravetz * not added by alloc_huge_page. We know it was added 2599846be085SMike Kravetz * before the alloc_huge_page call, otherwise 2600846be085SMike Kravetz * HPageRestoreReserve would be set on the page. 2601846be085SMike Kravetz * Remove the entry so that a subsequent allocation 2602846be085SMike Kravetz * does not consume a reservation. 260396b96a96SMike Kravetz */ 2604846be085SMike Kravetz rc = vma_del_reservation(h, vma, address); 2605846be085SMike Kravetz if (rc < 0) 2606846be085SMike Kravetz /* 2607846be085SMike Kravetz * VERY rare out of memory condition. Since 2608846be085SMike Kravetz * we can not delete the entry, set 2609846be085SMike Kravetz * HPageRestoreReserve so that the reserve 2610846be085SMike Kravetz * count will be incremented when the page 2611846be085SMike Kravetz * is freed. This reserve will be consumed 2612846be085SMike Kravetz * on a subsequent allocation. 2613846be085SMike Kravetz */ 2614846be085SMike Kravetz SetHPageRestoreReserve(page); 2615846be085SMike Kravetz } else if (rc < 0) { 2616846be085SMike Kravetz /* 2617846be085SMike Kravetz * Rare out of memory condition from 2618846be085SMike Kravetz * vma_needs_reservation call. Memory allocation is 2619846be085SMike Kravetz * only attempted if a new entry is needed. Therefore, 2620846be085SMike Kravetz * this implies there is not an entry in the 2621846be085SMike Kravetz * reserve map. 2622846be085SMike Kravetz * 2623846be085SMike Kravetz * For shared mappings, no entry in the map indicates 2624846be085SMike Kravetz * no reservation. We are done. 2625846be085SMike Kravetz */ 2626846be085SMike Kravetz if (!(vma->vm_flags & VM_MAYSHARE)) 2627846be085SMike Kravetz /* 2628846be085SMike Kravetz * For private mappings, no entry indicates 2629846be085SMike Kravetz * a reservation is present. Since we can 2630846be085SMike Kravetz * not add an entry, set SetHPageRestoreReserve 2631846be085SMike Kravetz * on the page so reserve count will be 2632846be085SMike Kravetz * incremented when freed. This reserve will 2633846be085SMike Kravetz * be consumed on a subsequent allocation. 2634846be085SMike Kravetz */ 2635846be085SMike Kravetz SetHPageRestoreReserve(page); 263696b96a96SMike Kravetz } else 2637846be085SMike Kravetz /* 2638846be085SMike Kravetz * No reservation present, do nothing 2639846be085SMike Kravetz */ 264096b96a96SMike Kravetz vma_end_reservation(h, vma, address); 264196b96a96SMike Kravetz } 264296b96a96SMike Kravetz } 264396b96a96SMike Kravetz 2644369fa227SOscar Salvador /* 2645369fa227SOscar Salvador * alloc_and_dissolve_huge_page - Allocate a new page and dissolve the old one 2646369fa227SOscar Salvador * @h: struct hstate old page belongs to 2647369fa227SOscar Salvador * @old_page: Old page to dissolve 2648ae37c7ffSOscar Salvador * @list: List to isolate the page in case we need to 2649369fa227SOscar Salvador * Returns 0 on success, otherwise negated error. 2650369fa227SOscar Salvador */ 2651ae37c7ffSOscar Salvador static int alloc_and_dissolve_huge_page(struct hstate *h, struct page *old_page, 2652ae37c7ffSOscar Salvador struct list_head *list) 2653369fa227SOscar Salvador { 2654369fa227SOscar Salvador gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE; 2655369fa227SOscar Salvador int nid = page_to_nid(old_page); 2656b65a4edaSMike Kravetz bool alloc_retry = false; 2657369fa227SOscar Salvador struct page *new_page; 2658369fa227SOscar Salvador int ret = 0; 2659369fa227SOscar Salvador 2660369fa227SOscar Salvador /* 2661369fa227SOscar Salvador * Before dissolving the page, we need to allocate a new one for the 2662f41f2ed4SMuchun Song * pool to remain stable. Here, we allocate the page and 'prep' it 2663f41f2ed4SMuchun Song * by doing everything but actually updating counters and adding to 2664f41f2ed4SMuchun Song * the pool. This simplifies and let us do most of the processing 2665f41f2ed4SMuchun Song * under the lock. 2666369fa227SOscar Salvador */ 2667b65a4edaSMike Kravetz alloc_retry: 2668369fa227SOscar Salvador new_page = alloc_buddy_huge_page(h, gfp_mask, nid, NULL, NULL); 2669369fa227SOscar Salvador if (!new_page) 2670369fa227SOscar Salvador return -ENOMEM; 2671b65a4edaSMike Kravetz /* 2672b65a4edaSMike Kravetz * If all goes well, this page will be directly added to the free 2673b65a4edaSMike Kravetz * list in the pool. For this the ref count needs to be zero. 2674b65a4edaSMike Kravetz * Attempt to drop now, and retry once if needed. It is VERY 2675b65a4edaSMike Kravetz * unlikely there is another ref on the page. 2676b65a4edaSMike Kravetz * 2677b65a4edaSMike Kravetz * If someone else has a reference to the page, it will be freed 2678b65a4edaSMike Kravetz * when they drop their ref. Abuse temporary page flag to accomplish 2679b65a4edaSMike Kravetz * this. Retry once if there is an inflated ref count. 2680b65a4edaSMike Kravetz */ 2681b65a4edaSMike Kravetz SetHPageTemporary(new_page); 2682b65a4edaSMike Kravetz if (!put_page_testzero(new_page)) { 2683b65a4edaSMike Kravetz if (alloc_retry) 2684b65a4edaSMike Kravetz return -EBUSY; 2685b65a4edaSMike Kravetz 2686b65a4edaSMike Kravetz alloc_retry = true; 2687b65a4edaSMike Kravetz goto alloc_retry; 2688b65a4edaSMike Kravetz } 2689b65a4edaSMike Kravetz ClearHPageTemporary(new_page); 2690b65a4edaSMike Kravetz 2691f41f2ed4SMuchun Song __prep_new_huge_page(h, new_page); 2692369fa227SOscar Salvador 2693369fa227SOscar Salvador retry: 2694369fa227SOscar Salvador spin_lock_irq(&hugetlb_lock); 2695369fa227SOscar Salvador if (!PageHuge(old_page)) { 2696369fa227SOscar Salvador /* 2697369fa227SOscar Salvador * Freed from under us. Drop new_page too. 2698369fa227SOscar Salvador */ 2699369fa227SOscar Salvador goto free_new; 2700369fa227SOscar Salvador } else if (page_count(old_page)) { 2701369fa227SOscar Salvador /* 2702ae37c7ffSOscar Salvador * Someone has grabbed the page, try to isolate it here. 2703ae37c7ffSOscar Salvador * Fail with -EBUSY if not possible. 2704369fa227SOscar Salvador */ 2705ae37c7ffSOscar Salvador spin_unlock_irq(&hugetlb_lock); 2706ae37c7ffSOscar Salvador if (!isolate_huge_page(old_page, list)) 2707369fa227SOscar Salvador ret = -EBUSY; 2708ae37c7ffSOscar Salvador spin_lock_irq(&hugetlb_lock); 2709369fa227SOscar Salvador goto free_new; 2710369fa227SOscar Salvador } else if (!HPageFreed(old_page)) { 2711369fa227SOscar Salvador /* 2712369fa227SOscar Salvador * Page's refcount is 0 but it has not been enqueued in the 2713369fa227SOscar Salvador * freelist yet. Race window is small, so we can succeed here if 2714369fa227SOscar Salvador * we retry. 2715369fa227SOscar Salvador */ 2716369fa227SOscar Salvador spin_unlock_irq(&hugetlb_lock); 2717369fa227SOscar Salvador cond_resched(); 2718369fa227SOscar Salvador goto retry; 2719369fa227SOscar Salvador } else { 2720369fa227SOscar Salvador /* 2721369fa227SOscar Salvador * Ok, old_page is still a genuine free hugepage. Remove it from 2722369fa227SOscar Salvador * the freelist and decrease the counters. These will be 2723369fa227SOscar Salvador * incremented again when calling __prep_account_new_huge_page() 2724369fa227SOscar Salvador * and enqueue_huge_page() for new_page. The counters will remain 2725369fa227SOscar Salvador * stable since this happens under the lock. 2726369fa227SOscar Salvador */ 2727369fa227SOscar Salvador remove_hugetlb_page(h, old_page, false); 2728369fa227SOscar Salvador 2729369fa227SOscar Salvador /* 2730b65a4edaSMike Kravetz * Ref count on new page is already zero as it was dropped 2731b65a4edaSMike Kravetz * earlier. It can be directly added to the pool free list. 2732369fa227SOscar Salvador */ 2733369fa227SOscar Salvador __prep_account_new_huge_page(h, nid); 2734369fa227SOscar Salvador enqueue_huge_page(h, new_page); 2735369fa227SOscar Salvador 2736369fa227SOscar Salvador /* 2737369fa227SOscar Salvador * Pages have been replaced, we can safely free the old one. 2738369fa227SOscar Salvador */ 2739369fa227SOscar Salvador spin_unlock_irq(&hugetlb_lock); 2740b65d4adbSMuchun Song update_and_free_page(h, old_page, false); 2741369fa227SOscar Salvador } 2742369fa227SOscar Salvador 2743369fa227SOscar Salvador return ret; 2744369fa227SOscar Salvador 2745369fa227SOscar Salvador free_new: 2746369fa227SOscar Salvador spin_unlock_irq(&hugetlb_lock); 2747b65a4edaSMike Kravetz /* Page has a zero ref count, but needs a ref to be freed */ 2748b65a4edaSMike Kravetz set_page_refcounted(new_page); 2749b65d4adbSMuchun Song update_and_free_page(h, new_page, false); 2750369fa227SOscar Salvador 2751369fa227SOscar Salvador return ret; 2752369fa227SOscar Salvador } 2753369fa227SOscar Salvador 2754ae37c7ffSOscar Salvador int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list) 2755369fa227SOscar Salvador { 2756369fa227SOscar Salvador struct hstate *h; 2757369fa227SOscar Salvador struct page *head; 2758ae37c7ffSOscar Salvador int ret = -EBUSY; 2759369fa227SOscar Salvador 2760369fa227SOscar Salvador /* 2761369fa227SOscar Salvador * The page might have been dissolved from under our feet, so make sure 2762369fa227SOscar Salvador * to carefully check the state under the lock. 2763369fa227SOscar Salvador * Return success when racing as if we dissolved the page ourselves. 2764369fa227SOscar Salvador */ 2765369fa227SOscar Salvador spin_lock_irq(&hugetlb_lock); 2766369fa227SOscar Salvador if (PageHuge(page)) { 2767369fa227SOscar Salvador head = compound_head(page); 2768369fa227SOscar Salvador h = page_hstate(head); 2769369fa227SOscar Salvador } else { 2770369fa227SOscar Salvador spin_unlock_irq(&hugetlb_lock); 2771369fa227SOscar Salvador return 0; 2772369fa227SOscar Salvador } 2773369fa227SOscar Salvador spin_unlock_irq(&hugetlb_lock); 2774369fa227SOscar Salvador 2775369fa227SOscar Salvador /* 2776369fa227SOscar Salvador * Fence off gigantic pages as there is a cyclic dependency between 2777369fa227SOscar Salvador * alloc_contig_range and them. Return -ENOMEM as this has the effect 2778369fa227SOscar Salvador * of bailing out right away without further retrying. 2779369fa227SOscar Salvador */ 2780369fa227SOscar Salvador if (hstate_is_gigantic(h)) 2781369fa227SOscar Salvador return -ENOMEM; 2782369fa227SOscar Salvador 2783ae37c7ffSOscar Salvador if (page_count(head) && isolate_huge_page(head, list)) 2784ae37c7ffSOscar Salvador ret = 0; 2785ae37c7ffSOscar Salvador else if (!page_count(head)) 2786ae37c7ffSOscar Salvador ret = alloc_and_dissolve_huge_page(h, head, list); 2787ae37c7ffSOscar Salvador 2788ae37c7ffSOscar Salvador return ret; 2789369fa227SOscar Salvador } 2790369fa227SOscar Salvador 279170c3547eSMike Kravetz struct page *alloc_huge_page(struct vm_area_struct *vma, 279204f2cbe3SMel Gorman unsigned long addr, int avoid_reserve) 2793348ea204SAdam Litke { 279490481622SDavid Gibson struct hugepage_subpool *spool = subpool_vma(vma); 2795a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 2796348ea204SAdam Litke struct page *page; 2797d85f69b0SMike Kravetz long map_chg, map_commit; 2798d85f69b0SMike Kravetz long gbl_chg; 27996d76dcf4SAneesh Kumar K.V int ret, idx; 28006d76dcf4SAneesh Kumar K.V struct hugetlb_cgroup *h_cg; 280108cf9fafSMina Almasry bool deferred_reserve; 28022fc39cecSAdam Litke 28036d76dcf4SAneesh Kumar K.V idx = hstate_index(h); 2804a1e78772SMel Gorman /* 2805d85f69b0SMike Kravetz * Examine the region/reserve map to determine if the process 2806d85f69b0SMike Kravetz * has a reservation for the page to be allocated. A return 2807d85f69b0SMike Kravetz * code of zero indicates a reservation exists (no change). 2808a1e78772SMel Gorman */ 2809d85f69b0SMike Kravetz map_chg = gbl_chg = vma_needs_reservation(h, vma, addr); 2810d85f69b0SMike Kravetz if (map_chg < 0) 281176dcee75SAneesh Kumar K.V return ERR_PTR(-ENOMEM); 2812d85f69b0SMike Kravetz 2813d85f69b0SMike Kravetz /* 2814d85f69b0SMike Kravetz * Processes that did not create the mapping will have no 2815d85f69b0SMike Kravetz * reserves as indicated by the region/reserve map. Check 2816d85f69b0SMike Kravetz * that the allocation will not exceed the subpool limit. 2817d85f69b0SMike Kravetz * Allocations for MAP_NORESERVE mappings also need to be 2818d85f69b0SMike Kravetz * checked against any subpool limit. 2819d85f69b0SMike Kravetz */ 2820d85f69b0SMike Kravetz if (map_chg || avoid_reserve) { 2821d85f69b0SMike Kravetz gbl_chg = hugepage_subpool_get_pages(spool, 1); 2822d85f69b0SMike Kravetz if (gbl_chg < 0) { 2823feba16e2SMike Kravetz vma_end_reservation(h, vma, addr); 282476dcee75SAneesh Kumar K.V return ERR_PTR(-ENOSPC); 28255e911373SMike Kravetz } 282690d8b7e6SAdam Litke 2827d85f69b0SMike Kravetz /* 2828d85f69b0SMike Kravetz * Even though there was no reservation in the region/reserve 2829d85f69b0SMike Kravetz * map, there could be reservations associated with the 2830d85f69b0SMike Kravetz * subpool that can be used. This would be indicated if the 2831d85f69b0SMike Kravetz * return value of hugepage_subpool_get_pages() is zero. 2832d85f69b0SMike Kravetz * However, if avoid_reserve is specified we still avoid even 2833d85f69b0SMike Kravetz * the subpool reservations. 2834d85f69b0SMike Kravetz */ 2835d85f69b0SMike Kravetz if (avoid_reserve) 2836d85f69b0SMike Kravetz gbl_chg = 1; 2837d85f69b0SMike Kravetz } 2838d85f69b0SMike Kravetz 283908cf9fafSMina Almasry /* If this allocation is not consuming a reservation, charge it now. 284008cf9fafSMina Almasry */ 28416501fe5fSMiaohe Lin deferred_reserve = map_chg || avoid_reserve; 284208cf9fafSMina Almasry if (deferred_reserve) { 284308cf9fafSMina Almasry ret = hugetlb_cgroup_charge_cgroup_rsvd( 284408cf9fafSMina Almasry idx, pages_per_huge_page(h), &h_cg); 28458f34af6fSJianyu Zhan if (ret) 28468f34af6fSJianyu Zhan goto out_subpool_put; 284708cf9fafSMina Almasry } 284808cf9fafSMina Almasry 284908cf9fafSMina Almasry ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg); 285008cf9fafSMina Almasry if (ret) 285108cf9fafSMina Almasry goto out_uncharge_cgroup_reservation; 28528f34af6fSJianyu Zhan 2853db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 2854d85f69b0SMike Kravetz /* 2855d85f69b0SMike Kravetz * glb_chg is passed to indicate whether or not a page must be taken 2856d85f69b0SMike Kravetz * from the global free pool (global change). gbl_chg == 0 indicates 2857d85f69b0SMike Kravetz * a reservation exists for the allocation. 2858d85f69b0SMike Kravetz */ 2859d85f69b0SMike Kravetz page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, gbl_chg); 286081a6fcaeSJoonsoo Kim if (!page) { 2861db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 28620c397daeSMichal Hocko page = alloc_buddy_huge_page_with_mpol(h, vma, addr); 28638f34af6fSJianyu Zhan if (!page) 28648f34af6fSJianyu Zhan goto out_uncharge_cgroup; 2865a88c7695SNaoya Horiguchi if (!avoid_reserve && vma_has_reserves(vma, gbl_chg)) { 2866d6995da3SMike Kravetz SetHPageRestoreReserve(page); 2867a88c7695SNaoya Horiguchi h->resv_huge_pages--; 2868a88c7695SNaoya Horiguchi } 2869db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 287015a8d68eSWei Yang list_add(&page->lru, &h->hugepage_activelist); 287181a6fcaeSJoonsoo Kim /* Fall through */ 2872a1e78772SMel Gorman } 287381a6fcaeSJoonsoo Kim hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, page); 287408cf9fafSMina Almasry /* If allocation is not consuming a reservation, also store the 287508cf9fafSMina Almasry * hugetlb_cgroup pointer on the page. 287608cf9fafSMina Almasry */ 287708cf9fafSMina Almasry if (deferred_reserve) { 287808cf9fafSMina Almasry hugetlb_cgroup_commit_charge_rsvd(idx, pages_per_huge_page(h), 287908cf9fafSMina Almasry h_cg, page); 288008cf9fafSMina Almasry } 288108cf9fafSMina Almasry 2882db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 2883a1e78772SMel Gorman 2884d6995da3SMike Kravetz hugetlb_set_page_subpool(page, spool); 2885a1e78772SMel Gorman 2886d85f69b0SMike Kravetz map_commit = vma_commit_reservation(h, vma, addr); 2887d85f69b0SMike Kravetz if (unlikely(map_chg > map_commit)) { 288833039678SMike Kravetz /* 288933039678SMike Kravetz * The page was added to the reservation map between 289033039678SMike Kravetz * vma_needs_reservation and vma_commit_reservation. 289133039678SMike Kravetz * This indicates a race with hugetlb_reserve_pages. 289233039678SMike Kravetz * Adjust for the subpool count incremented above AND 289333039678SMike Kravetz * in hugetlb_reserve_pages for the same page. Also, 289433039678SMike Kravetz * the reservation count added in hugetlb_reserve_pages 289533039678SMike Kravetz * no longer applies. 289633039678SMike Kravetz */ 289733039678SMike Kravetz long rsv_adjust; 289833039678SMike Kravetz 289933039678SMike Kravetz rsv_adjust = hugepage_subpool_put_pages(spool, 1); 290033039678SMike Kravetz hugetlb_acct_memory(h, -rsv_adjust); 290179aa925bSMike Kravetz if (deferred_reserve) 290279aa925bSMike Kravetz hugetlb_cgroup_uncharge_page_rsvd(hstate_index(h), 290379aa925bSMike Kravetz pages_per_huge_page(h), page); 290433039678SMike Kravetz } 29057893d1d5SAdam Litke return page; 29068f34af6fSJianyu Zhan 29078f34af6fSJianyu Zhan out_uncharge_cgroup: 29088f34af6fSJianyu Zhan hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg); 290908cf9fafSMina Almasry out_uncharge_cgroup_reservation: 291008cf9fafSMina Almasry if (deferred_reserve) 291108cf9fafSMina Almasry hugetlb_cgroup_uncharge_cgroup_rsvd(idx, pages_per_huge_page(h), 291208cf9fafSMina Almasry h_cg); 29138f34af6fSJianyu Zhan out_subpool_put: 2914d85f69b0SMike Kravetz if (map_chg || avoid_reserve) 29158f34af6fSJianyu Zhan hugepage_subpool_put_pages(spool, 1); 2916feba16e2SMike Kravetz vma_end_reservation(h, vma, addr); 29178f34af6fSJianyu Zhan return ERR_PTR(-ENOSPC); 2918b45b5bd6SDavid Gibson } 2919b45b5bd6SDavid Gibson 2920e24a1307SAneesh Kumar K.V int alloc_bootmem_huge_page(struct hstate *h) 2921e24a1307SAneesh Kumar K.V __attribute__ ((weak, alias("__alloc_bootmem_huge_page"))); 2922e24a1307SAneesh Kumar K.V int __alloc_bootmem_huge_page(struct hstate *h) 2923aa888a74SAndi Kleen { 2924aa888a74SAndi Kleen struct huge_bootmem_page *m; 2925b2261026SJoonsoo Kim int nr_nodes, node; 2926aa888a74SAndi Kleen 2927b2261026SJoonsoo Kim for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) { 2928aa888a74SAndi Kleen void *addr; 2929aa888a74SAndi Kleen 2930eb31d559SMike Rapoport addr = memblock_alloc_try_nid_raw( 29318b89a116SGrygorii Strashko huge_page_size(h), huge_page_size(h), 293297ad1087SMike Rapoport 0, MEMBLOCK_ALLOC_ACCESSIBLE, node); 2933aa888a74SAndi Kleen if (addr) { 2934aa888a74SAndi Kleen /* 2935aa888a74SAndi Kleen * Use the beginning of the huge page to store the 2936aa888a74SAndi Kleen * huge_bootmem_page struct (until gather_bootmem 2937aa888a74SAndi Kleen * puts them into the mem_map). 2938aa888a74SAndi Kleen */ 2939aa888a74SAndi Kleen m = addr; 2940aa888a74SAndi Kleen goto found; 2941aa888a74SAndi Kleen } 2942aa888a74SAndi Kleen } 2943aa888a74SAndi Kleen return 0; 2944aa888a74SAndi Kleen 2945aa888a74SAndi Kleen found: 2946df994eadSLuiz Capitulino BUG_ON(!IS_ALIGNED(virt_to_phys(m), huge_page_size(h))); 2947aa888a74SAndi Kleen /* Put them into a private list first because mem_map is not up yet */ 2948330d6e48SCannon Matthews INIT_LIST_HEAD(&m->list); 2949aa888a74SAndi Kleen list_add(&m->list, &huge_boot_pages); 2950aa888a74SAndi Kleen m->hstate = h; 2951aa888a74SAndi Kleen return 1; 2952aa888a74SAndi Kleen } 2953aa888a74SAndi Kleen 295448b8d744SMike Kravetz /* 295548b8d744SMike Kravetz * Put bootmem huge pages into the standard lists after mem_map is up. 295648b8d744SMike Kravetz * Note: This only applies to gigantic (order > MAX_ORDER) pages. 295748b8d744SMike Kravetz */ 2958aa888a74SAndi Kleen static void __init gather_bootmem_prealloc(void) 2959aa888a74SAndi Kleen { 2960aa888a74SAndi Kleen struct huge_bootmem_page *m; 2961aa888a74SAndi Kleen 2962aa888a74SAndi Kleen list_for_each_entry(m, &huge_boot_pages, list) { 296340d18ebfSMike Kravetz struct page *page = virt_to_page(m); 2964aa888a74SAndi Kleen struct hstate *h = m->hstate; 2965ee8f248dSBecky Bruce 296648b8d744SMike Kravetz VM_BUG_ON(!hstate_is_gigantic(h)); 2967aa888a74SAndi Kleen WARN_ON(page_count(page) != 1); 29687118fc29SMike Kravetz if (prep_compound_gigantic_page(page, huge_page_order(h))) { 2969ef5a22beSAndrea Arcangeli WARN_ON(PageReserved(page)); 2970aa888a74SAndi Kleen prep_new_huge_page(h, page, page_to_nid(page)); 29717118fc29SMike Kravetz put_page(page); /* add to the hugepage allocator */ 29727118fc29SMike Kravetz } else { 2973416d85edSMike Kravetz /* VERY unlikely inflated ref count on a tail page */ 29747118fc29SMike Kravetz free_gigantic_page(page, huge_page_order(h)); 29757118fc29SMike Kravetz } 2976af0fb9dfSMichal Hocko 2977b0320c7bSRafael Aquini /* 297848b8d744SMike Kravetz * We need to restore the 'stolen' pages to totalram_pages 297948b8d744SMike Kravetz * in order to fix confusing memory reports from free(1) and 298048b8d744SMike Kravetz * other side-effects, like CommitLimit going negative. 2981b0320c7bSRafael Aquini */ 2982c78a7f36SMiaohe Lin adjust_managed_page_count(page, pages_per_huge_page(h)); 2983520495feSCannon Matthews cond_resched(); 2984aa888a74SAndi Kleen } 2985aa888a74SAndi Kleen } 2986aa888a74SAndi Kleen 29878faa8b07SAndi Kleen static void __init hugetlb_hstate_alloc_pages(struct hstate *h) 29881da177e4SLinus Torvalds { 29891da177e4SLinus Torvalds unsigned long i; 2990f60858f9SMike Kravetz nodemask_t *node_alloc_noretry; 2991f60858f9SMike Kravetz 2992f60858f9SMike Kravetz if (!hstate_is_gigantic(h)) { 2993f60858f9SMike Kravetz /* 2994f60858f9SMike Kravetz * Bit mask controlling how hard we retry per-node allocations. 2995f60858f9SMike Kravetz * Ignore errors as lower level routines can deal with 2996f60858f9SMike Kravetz * node_alloc_noretry == NULL. If this kmalloc fails at boot 2997f60858f9SMike Kravetz * time, we are likely in bigger trouble. 2998f60858f9SMike Kravetz */ 2999f60858f9SMike Kravetz node_alloc_noretry = kmalloc(sizeof(*node_alloc_noretry), 3000f60858f9SMike Kravetz GFP_KERNEL); 3001f60858f9SMike Kravetz } else { 3002f60858f9SMike Kravetz /* allocations done at boot time */ 3003f60858f9SMike Kravetz node_alloc_noretry = NULL; 3004f60858f9SMike Kravetz } 3005f60858f9SMike Kravetz 3006f60858f9SMike Kravetz /* bit mask controlling how hard we retry per-node allocations */ 3007f60858f9SMike Kravetz if (node_alloc_noretry) 3008f60858f9SMike Kravetz nodes_clear(*node_alloc_noretry); 30091da177e4SLinus Torvalds 3010e5ff2159SAndi Kleen for (i = 0; i < h->max_huge_pages; ++i) { 3011bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) { 3012dbda8feaSBarry Song if (hugetlb_cma_size) { 3013cf11e85fSRoman Gushchin pr_warn_once("HugeTLB: hugetlb_cma is enabled, skip boot time allocation\n"); 30147ecc9565SChen Wandun goto free; 3015cf11e85fSRoman Gushchin } 3016aa888a74SAndi Kleen if (!alloc_bootmem_huge_page(h)) 3017aa888a74SAndi Kleen break; 30180c397daeSMichal Hocko } else if (!alloc_pool_huge_page(h, 3019f60858f9SMike Kravetz &node_states[N_MEMORY], 3020f60858f9SMike Kravetz node_alloc_noretry)) 30211da177e4SLinus Torvalds break; 302269ed779aSDavid Rientjes cond_resched(); 30231da177e4SLinus Torvalds } 3024d715cf80SLiam R. Howlett if (i < h->max_huge_pages) { 3025d715cf80SLiam R. Howlett char buf[32]; 3026d715cf80SLiam R. Howlett 3027c6247f72SMatthew Wilcox string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); 3028d715cf80SLiam R. Howlett pr_warn("HugeTLB: allocating %lu of page size %s failed. Only allocated %lu hugepages.\n", 3029d715cf80SLiam R. Howlett h->max_huge_pages, buf, i); 30308faa8b07SAndi Kleen h->max_huge_pages = i; 3031e5ff2159SAndi Kleen } 30327ecc9565SChen Wandun free: 3033f60858f9SMike Kravetz kfree(node_alloc_noretry); 3034d715cf80SLiam R. Howlett } 3035e5ff2159SAndi Kleen 3036e5ff2159SAndi Kleen static void __init hugetlb_init_hstates(void) 3037e5ff2159SAndi Kleen { 303879dfc695SMike Kravetz struct hstate *h, *h2; 3039e5ff2159SAndi Kleen 3040e5ff2159SAndi Kleen for_each_hstate(h) { 3041641844f5SNaoya Horiguchi if (minimum_order > huge_page_order(h)) 3042641844f5SNaoya Horiguchi minimum_order = huge_page_order(h); 3043641844f5SNaoya Horiguchi 30448faa8b07SAndi Kleen /* oversize hugepages were init'ed in early boot */ 3045bae7f4aeSLuiz Capitulino if (!hstate_is_gigantic(h)) 30468faa8b07SAndi Kleen hugetlb_hstate_alloc_pages(h); 304779dfc695SMike Kravetz 304879dfc695SMike Kravetz /* 304979dfc695SMike Kravetz * Set demote order for each hstate. Note that 305079dfc695SMike Kravetz * h->demote_order is initially 0. 305179dfc695SMike Kravetz * - We can not demote gigantic pages if runtime freeing 305279dfc695SMike Kravetz * is not supported, so skip this. 3053a01f4390SMike Kravetz * - If CMA allocation is possible, we can not demote 3054a01f4390SMike Kravetz * HUGETLB_PAGE_ORDER or smaller size pages. 305579dfc695SMike Kravetz */ 305679dfc695SMike Kravetz if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) 305779dfc695SMike Kravetz continue; 3058a01f4390SMike Kravetz if (hugetlb_cma_size && h->order <= HUGETLB_PAGE_ORDER) 3059a01f4390SMike Kravetz continue; 306079dfc695SMike Kravetz for_each_hstate(h2) { 306179dfc695SMike Kravetz if (h2 == h) 306279dfc695SMike Kravetz continue; 306379dfc695SMike Kravetz if (h2->order < h->order && 306479dfc695SMike Kravetz h2->order > h->demote_order) 306579dfc695SMike Kravetz h->demote_order = h2->order; 306679dfc695SMike Kravetz } 3067e5ff2159SAndi Kleen } 3068641844f5SNaoya Horiguchi VM_BUG_ON(minimum_order == UINT_MAX); 3069e5ff2159SAndi Kleen } 3070e5ff2159SAndi Kleen 3071e5ff2159SAndi Kleen static void __init report_hugepages(void) 3072e5ff2159SAndi Kleen { 3073e5ff2159SAndi Kleen struct hstate *h; 3074e5ff2159SAndi Kleen 3075e5ff2159SAndi Kleen for_each_hstate(h) { 30764abd32dbSAndi Kleen char buf[32]; 3077c6247f72SMatthew Wilcox 3078c6247f72SMatthew Wilcox string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32); 3079ffb22af5SAndrew Morton pr_info("HugeTLB registered %s page size, pre-allocated %ld pages\n", 3080c6247f72SMatthew Wilcox buf, h->free_huge_pages); 3081e5ff2159SAndi Kleen } 3082e5ff2159SAndi Kleen } 3083e5ff2159SAndi Kleen 30841da177e4SLinus Torvalds #ifdef CONFIG_HIGHMEM 30856ae11b27SLee Schermerhorn static void try_to_free_low(struct hstate *h, unsigned long count, 30866ae11b27SLee Schermerhorn nodemask_t *nodes_allowed) 30871da177e4SLinus Torvalds { 30884415cc8dSChristoph Lameter int i; 30891121828aSMike Kravetz LIST_HEAD(page_list); 30904415cc8dSChristoph Lameter 30919487ca60SMike Kravetz lockdep_assert_held(&hugetlb_lock); 3092bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 3093aa888a74SAndi Kleen return; 3094aa888a74SAndi Kleen 30951121828aSMike Kravetz /* 30961121828aSMike Kravetz * Collect pages to be freed on a list, and free after dropping lock 30971121828aSMike Kravetz */ 30986ae11b27SLee Schermerhorn for_each_node_mask(i, *nodes_allowed) { 309910c6ec49SMike Kravetz struct page *page, *next; 3100a5516438SAndi Kleen struct list_head *freel = &h->hugepage_freelists[i]; 3101a5516438SAndi Kleen list_for_each_entry_safe(page, next, freel, lru) { 3102a5516438SAndi Kleen if (count >= h->nr_huge_pages) 31031121828aSMike Kravetz goto out; 31041da177e4SLinus Torvalds if (PageHighMem(page)) 31051da177e4SLinus Torvalds continue; 31066eb4e88aSMike Kravetz remove_hugetlb_page(h, page, false); 31071121828aSMike Kravetz list_add(&page->lru, &page_list); 31081121828aSMike Kravetz } 31091121828aSMike Kravetz } 31101121828aSMike Kravetz 31111121828aSMike Kravetz out: 3112db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 311310c6ec49SMike Kravetz update_and_free_pages_bulk(h, &page_list); 3114db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 31151da177e4SLinus Torvalds } 31161da177e4SLinus Torvalds #else 31176ae11b27SLee Schermerhorn static inline void try_to_free_low(struct hstate *h, unsigned long count, 31186ae11b27SLee Schermerhorn nodemask_t *nodes_allowed) 31191da177e4SLinus Torvalds { 31201da177e4SLinus Torvalds } 31211da177e4SLinus Torvalds #endif 31221da177e4SLinus Torvalds 312320a0307cSWu Fengguang /* 312420a0307cSWu Fengguang * Increment or decrement surplus_huge_pages. Keep node-specific counters 312520a0307cSWu Fengguang * balanced by operating on them in a round-robin fashion. 312620a0307cSWu Fengguang * Returns 1 if an adjustment was made. 312720a0307cSWu Fengguang */ 31286ae11b27SLee Schermerhorn static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, 31296ae11b27SLee Schermerhorn int delta) 313020a0307cSWu Fengguang { 3131b2261026SJoonsoo Kim int nr_nodes, node; 313220a0307cSWu Fengguang 31339487ca60SMike Kravetz lockdep_assert_held(&hugetlb_lock); 313420a0307cSWu Fengguang VM_BUG_ON(delta != -1 && delta != 1); 313520a0307cSWu Fengguang 3136e8c5c824SLee Schermerhorn if (delta < 0) { 3137b2261026SJoonsoo Kim for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { 3138b2261026SJoonsoo Kim if (h->surplus_huge_pages_node[node]) 3139b2261026SJoonsoo Kim goto found; 3140b2261026SJoonsoo Kim } 3141b2261026SJoonsoo Kim } else { 3142b2261026SJoonsoo Kim for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { 3143b2261026SJoonsoo Kim if (h->surplus_huge_pages_node[node] < 3144b2261026SJoonsoo Kim h->nr_huge_pages_node[node]) 3145b2261026SJoonsoo Kim goto found; 3146e8c5c824SLee Schermerhorn } 31479a76db09SLee Schermerhorn } 3148b2261026SJoonsoo Kim return 0; 314920a0307cSWu Fengguang 3150b2261026SJoonsoo Kim found: 315120a0307cSWu Fengguang h->surplus_huge_pages += delta; 3152b2261026SJoonsoo Kim h->surplus_huge_pages_node[node] += delta; 3153b2261026SJoonsoo Kim return 1; 315420a0307cSWu Fengguang } 315520a0307cSWu Fengguang 3156a5516438SAndi Kleen #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) 3157fd875dcaSMike Kravetz static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid, 31586ae11b27SLee Schermerhorn nodemask_t *nodes_allowed) 31591da177e4SLinus Torvalds { 31607893d1d5SAdam Litke unsigned long min_count, ret; 316110c6ec49SMike Kravetz struct page *page; 316210c6ec49SMike Kravetz LIST_HEAD(page_list); 3163f60858f9SMike Kravetz NODEMASK_ALLOC(nodemask_t, node_alloc_noretry, GFP_KERNEL); 3164f60858f9SMike Kravetz 3165f60858f9SMike Kravetz /* 3166f60858f9SMike Kravetz * Bit mask controlling how hard we retry per-node allocations. 3167f60858f9SMike Kravetz * If we can not allocate the bit mask, do not attempt to allocate 3168f60858f9SMike Kravetz * the requested huge pages. 3169f60858f9SMike Kravetz */ 3170f60858f9SMike Kravetz if (node_alloc_noretry) 3171f60858f9SMike Kravetz nodes_clear(*node_alloc_noretry); 3172f60858f9SMike Kravetz else 3173f60858f9SMike Kravetz return -ENOMEM; 31741da177e4SLinus Torvalds 317529383967SMike Kravetz /* 317629383967SMike Kravetz * resize_lock mutex prevents concurrent adjustments to number of 317729383967SMike Kravetz * pages in hstate via the proc/sysfs interfaces. 317829383967SMike Kravetz */ 317929383967SMike Kravetz mutex_lock(&h->resize_lock); 3180b65d4adbSMuchun Song flush_free_hpage_work(h); 3181db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 31824eb0716eSAlexandre Ghiti 31834eb0716eSAlexandre Ghiti /* 3184fd875dcaSMike Kravetz * Check for a node specific request. 3185fd875dcaSMike Kravetz * Changing node specific huge page count may require a corresponding 3186fd875dcaSMike Kravetz * change to the global count. In any case, the passed node mask 3187fd875dcaSMike Kravetz * (nodes_allowed) will restrict alloc/free to the specified node. 3188fd875dcaSMike Kravetz */ 3189fd875dcaSMike Kravetz if (nid != NUMA_NO_NODE) { 3190fd875dcaSMike Kravetz unsigned long old_count = count; 3191fd875dcaSMike Kravetz 3192fd875dcaSMike Kravetz count += h->nr_huge_pages - h->nr_huge_pages_node[nid]; 3193fd875dcaSMike Kravetz /* 3194fd875dcaSMike Kravetz * User may have specified a large count value which caused the 3195fd875dcaSMike Kravetz * above calculation to overflow. In this case, they wanted 3196fd875dcaSMike Kravetz * to allocate as many huge pages as possible. Set count to 3197fd875dcaSMike Kravetz * largest possible value to align with their intention. 3198fd875dcaSMike Kravetz */ 3199fd875dcaSMike Kravetz if (count < old_count) 3200fd875dcaSMike Kravetz count = ULONG_MAX; 3201fd875dcaSMike Kravetz } 3202fd875dcaSMike Kravetz 3203fd875dcaSMike Kravetz /* 32044eb0716eSAlexandre Ghiti * Gigantic pages runtime allocation depend on the capability for large 32054eb0716eSAlexandre Ghiti * page range allocation. 32064eb0716eSAlexandre Ghiti * If the system does not provide this feature, return an error when 32074eb0716eSAlexandre Ghiti * the user tries to allocate gigantic pages but let the user free the 32084eb0716eSAlexandre Ghiti * boottime allocated gigantic pages. 32094eb0716eSAlexandre Ghiti */ 32104eb0716eSAlexandre Ghiti if (hstate_is_gigantic(h) && !IS_ENABLED(CONFIG_CONTIG_ALLOC)) { 32114eb0716eSAlexandre Ghiti if (count > persistent_huge_pages(h)) { 3212db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 321329383967SMike Kravetz mutex_unlock(&h->resize_lock); 3214f60858f9SMike Kravetz NODEMASK_FREE(node_alloc_noretry); 32154eb0716eSAlexandre Ghiti return -EINVAL; 32164eb0716eSAlexandre Ghiti } 32174eb0716eSAlexandre Ghiti /* Fall through to decrease pool */ 32184eb0716eSAlexandre Ghiti } 3219aa888a74SAndi Kleen 32207893d1d5SAdam Litke /* 32217893d1d5SAdam Litke * Increase the pool size 32227893d1d5SAdam Litke * First take pages out of surplus state. Then make up the 32237893d1d5SAdam Litke * remaining difference by allocating fresh huge pages. 3224d1c3fb1fSNishanth Aravamudan * 32250c397daeSMichal Hocko * We might race with alloc_surplus_huge_page() here and be unable 3226d1c3fb1fSNishanth Aravamudan * to convert a surplus huge page to a normal huge page. That is 3227d1c3fb1fSNishanth Aravamudan * not critical, though, it just means the overall size of the 3228d1c3fb1fSNishanth Aravamudan * pool might be one hugepage larger than it needs to be, but 3229d1c3fb1fSNishanth Aravamudan * within all the constraints specified by the sysctls. 32307893d1d5SAdam Litke */ 3231a5516438SAndi Kleen while (h->surplus_huge_pages && count > persistent_huge_pages(h)) { 32326ae11b27SLee Schermerhorn if (!adjust_pool_surplus(h, nodes_allowed, -1)) 32337893d1d5SAdam Litke break; 32347893d1d5SAdam Litke } 32357893d1d5SAdam Litke 3236a5516438SAndi Kleen while (count > persistent_huge_pages(h)) { 32377893d1d5SAdam Litke /* 32387893d1d5SAdam Litke * If this allocation races such that we no longer need the 32397893d1d5SAdam Litke * page, free_huge_page will handle it by freeing the page 32407893d1d5SAdam Litke * and reducing the surplus. 32417893d1d5SAdam Litke */ 3242db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 3243649920c6SJia He 3244649920c6SJia He /* yield cpu to avoid soft lockup */ 3245649920c6SJia He cond_resched(); 3246649920c6SJia He 3247f60858f9SMike Kravetz ret = alloc_pool_huge_page(h, nodes_allowed, 3248f60858f9SMike Kravetz node_alloc_noretry); 3249db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 32507893d1d5SAdam Litke if (!ret) 32517893d1d5SAdam Litke goto out; 32527893d1d5SAdam Litke 3253536240f2SMel Gorman /* Bail for signals. Probably ctrl-c from user */ 3254536240f2SMel Gorman if (signal_pending(current)) 3255536240f2SMel Gorman goto out; 32567893d1d5SAdam Litke } 32577893d1d5SAdam Litke 32587893d1d5SAdam Litke /* 32597893d1d5SAdam Litke * Decrease the pool size 32607893d1d5SAdam Litke * First return free pages to the buddy allocator (being careful 32617893d1d5SAdam Litke * to keep enough around to satisfy reservations). Then place 32627893d1d5SAdam Litke * pages into surplus state as needed so the pool will shrink 32637893d1d5SAdam Litke * to the desired size as pages become free. 3264d1c3fb1fSNishanth Aravamudan * 3265d1c3fb1fSNishanth Aravamudan * By placing pages into the surplus state independent of the 3266d1c3fb1fSNishanth Aravamudan * overcommit value, we are allowing the surplus pool size to 3267d1c3fb1fSNishanth Aravamudan * exceed overcommit. There are few sane options here. Since 32680c397daeSMichal Hocko * alloc_surplus_huge_page() is checking the global counter, 3269d1c3fb1fSNishanth Aravamudan * though, we'll note that we're not allowed to exceed surplus 3270d1c3fb1fSNishanth Aravamudan * and won't grow the pool anywhere else. Not until one of the 3271d1c3fb1fSNishanth Aravamudan * sysctls are changed, or the surplus pages go out of use. 32727893d1d5SAdam Litke */ 3273a5516438SAndi Kleen min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages; 32746b0c880dSAdam Litke min_count = max(count, min_count); 32756ae11b27SLee Schermerhorn try_to_free_low(h, min_count, nodes_allowed); 327610c6ec49SMike Kravetz 327710c6ec49SMike Kravetz /* 327810c6ec49SMike Kravetz * Collect pages to be removed on list without dropping lock 327910c6ec49SMike Kravetz */ 3280a5516438SAndi Kleen while (min_count < persistent_huge_pages(h)) { 328110c6ec49SMike Kravetz page = remove_pool_huge_page(h, nodes_allowed, 0); 328210c6ec49SMike Kravetz if (!page) 32831da177e4SLinus Torvalds break; 328410c6ec49SMike Kravetz 328510c6ec49SMike Kravetz list_add(&page->lru, &page_list); 32861da177e4SLinus Torvalds } 328710c6ec49SMike Kravetz /* free the pages after dropping lock */ 3288db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 328910c6ec49SMike Kravetz update_and_free_pages_bulk(h, &page_list); 3290b65d4adbSMuchun Song flush_free_hpage_work(h); 3291db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 329210c6ec49SMike Kravetz 3293a5516438SAndi Kleen while (count < persistent_huge_pages(h)) { 32946ae11b27SLee Schermerhorn if (!adjust_pool_surplus(h, nodes_allowed, 1)) 32957893d1d5SAdam Litke break; 32967893d1d5SAdam Litke } 32977893d1d5SAdam Litke out: 32984eb0716eSAlexandre Ghiti h->max_huge_pages = persistent_huge_pages(h); 3299db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 330029383967SMike Kravetz mutex_unlock(&h->resize_lock); 33014eb0716eSAlexandre Ghiti 3302f60858f9SMike Kravetz NODEMASK_FREE(node_alloc_noretry); 3303f60858f9SMike Kravetz 33044eb0716eSAlexandre Ghiti return 0; 33051da177e4SLinus Torvalds } 33061da177e4SLinus Torvalds 330779dfc695SMike Kravetz static int demote_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed) 330879dfc695SMike Kravetz __must_hold(&hugetlb_lock) 330979dfc695SMike Kravetz { 331079dfc695SMike Kravetz int rc = 0; 331179dfc695SMike Kravetz 331279dfc695SMike Kravetz lockdep_assert_held(&hugetlb_lock); 331379dfc695SMike Kravetz 331479dfc695SMike Kravetz /* We should never get here if no demote order */ 331579dfc695SMike Kravetz if (!h->demote_order) { 331679dfc695SMike Kravetz pr_warn("HugeTLB: NULL demote order passed to demote_pool_huge_page.\n"); 331779dfc695SMike Kravetz return -EINVAL; /* internal error */ 331879dfc695SMike Kravetz } 331979dfc695SMike Kravetz 332079dfc695SMike Kravetz /* 332179dfc695SMike Kravetz * TODO - demote fucntionality will be added in subsequent patch 332279dfc695SMike Kravetz */ 332379dfc695SMike Kravetz return rc; 332479dfc695SMike Kravetz } 332579dfc695SMike Kravetz 3326a3437870SNishanth Aravamudan #define HSTATE_ATTR_RO(_name) \ 3327a3437870SNishanth Aravamudan static struct kobj_attribute _name##_attr = __ATTR_RO(_name) 3328a3437870SNishanth Aravamudan 332979dfc695SMike Kravetz #define HSTATE_ATTR_WO(_name) \ 333079dfc695SMike Kravetz static struct kobj_attribute _name##_attr = __ATTR_WO(_name) 333179dfc695SMike Kravetz 3332a3437870SNishanth Aravamudan #define HSTATE_ATTR(_name) \ 3333a3437870SNishanth Aravamudan static struct kobj_attribute _name##_attr = \ 3334a3437870SNishanth Aravamudan __ATTR(_name, 0644, _name##_show, _name##_store) 3335a3437870SNishanth Aravamudan 3336a3437870SNishanth Aravamudan static struct kobject *hugepages_kobj; 3337a3437870SNishanth Aravamudan static struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; 3338a3437870SNishanth Aravamudan 33399a305230SLee Schermerhorn static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp); 33409a305230SLee Schermerhorn 33419a305230SLee Schermerhorn static struct hstate *kobj_to_hstate(struct kobject *kobj, int *nidp) 3342a3437870SNishanth Aravamudan { 3343a3437870SNishanth Aravamudan int i; 33449a305230SLee Schermerhorn 3345a3437870SNishanth Aravamudan for (i = 0; i < HUGE_MAX_HSTATE; i++) 33469a305230SLee Schermerhorn if (hstate_kobjs[i] == kobj) { 33479a305230SLee Schermerhorn if (nidp) 33489a305230SLee Schermerhorn *nidp = NUMA_NO_NODE; 3349a3437870SNishanth Aravamudan return &hstates[i]; 33509a305230SLee Schermerhorn } 33519a305230SLee Schermerhorn 33529a305230SLee Schermerhorn return kobj_to_node_hstate(kobj, nidp); 3353a3437870SNishanth Aravamudan } 3354a3437870SNishanth Aravamudan 335506808b08SLee Schermerhorn static ssize_t nr_hugepages_show_common(struct kobject *kobj, 3356a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 3357a3437870SNishanth Aravamudan { 33589a305230SLee Schermerhorn struct hstate *h; 33599a305230SLee Schermerhorn unsigned long nr_huge_pages; 33609a305230SLee Schermerhorn int nid; 33619a305230SLee Schermerhorn 33629a305230SLee Schermerhorn h = kobj_to_hstate(kobj, &nid); 33639a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) 33649a305230SLee Schermerhorn nr_huge_pages = h->nr_huge_pages; 33659a305230SLee Schermerhorn else 33669a305230SLee Schermerhorn nr_huge_pages = h->nr_huge_pages_node[nid]; 33679a305230SLee Schermerhorn 3368ae7a927dSJoe Perches return sysfs_emit(buf, "%lu\n", nr_huge_pages); 3369a3437870SNishanth Aravamudan } 3370adbe8726SEric B Munson 3371238d3c13SDavid Rientjes static ssize_t __nr_hugepages_store_common(bool obey_mempolicy, 3372238d3c13SDavid Rientjes struct hstate *h, int nid, 3373238d3c13SDavid Rientjes unsigned long count, size_t len) 3374a3437870SNishanth Aravamudan { 3375a3437870SNishanth Aravamudan int err; 33762d0adf7eSOscar Salvador nodemask_t nodes_allowed, *n_mask; 3377a3437870SNishanth Aravamudan 33782d0adf7eSOscar Salvador if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported()) 33792d0adf7eSOscar Salvador return -EINVAL; 3380adbe8726SEric B Munson 33819a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) { 33829a305230SLee Schermerhorn /* 33839a305230SLee Schermerhorn * global hstate attribute 33849a305230SLee Schermerhorn */ 33859a305230SLee Schermerhorn if (!(obey_mempolicy && 33862d0adf7eSOscar Salvador init_nodemask_of_mempolicy(&nodes_allowed))) 33872d0adf7eSOscar Salvador n_mask = &node_states[N_MEMORY]; 33882d0adf7eSOscar Salvador else 33892d0adf7eSOscar Salvador n_mask = &nodes_allowed; 33902d0adf7eSOscar Salvador } else { 33919a305230SLee Schermerhorn /* 3392fd875dcaSMike Kravetz * Node specific request. count adjustment happens in 3393fd875dcaSMike Kravetz * set_max_huge_pages() after acquiring hugetlb_lock. 33949a305230SLee Schermerhorn */ 33952d0adf7eSOscar Salvador init_nodemask_of_node(&nodes_allowed, nid); 33962d0adf7eSOscar Salvador n_mask = &nodes_allowed; 3397fd875dcaSMike Kravetz } 33989a305230SLee Schermerhorn 33992d0adf7eSOscar Salvador err = set_max_huge_pages(h, count, nid, n_mask); 340006808b08SLee Schermerhorn 34014eb0716eSAlexandre Ghiti return err ? err : len; 340206808b08SLee Schermerhorn } 340306808b08SLee Schermerhorn 3404238d3c13SDavid Rientjes static ssize_t nr_hugepages_store_common(bool obey_mempolicy, 3405238d3c13SDavid Rientjes struct kobject *kobj, const char *buf, 3406238d3c13SDavid Rientjes size_t len) 3407238d3c13SDavid Rientjes { 3408238d3c13SDavid Rientjes struct hstate *h; 3409238d3c13SDavid Rientjes unsigned long count; 3410238d3c13SDavid Rientjes int nid; 3411238d3c13SDavid Rientjes int err; 3412238d3c13SDavid Rientjes 3413238d3c13SDavid Rientjes err = kstrtoul(buf, 10, &count); 3414238d3c13SDavid Rientjes if (err) 3415238d3c13SDavid Rientjes return err; 3416238d3c13SDavid Rientjes 3417238d3c13SDavid Rientjes h = kobj_to_hstate(kobj, &nid); 3418238d3c13SDavid Rientjes return __nr_hugepages_store_common(obey_mempolicy, h, nid, count, len); 3419238d3c13SDavid Rientjes } 3420238d3c13SDavid Rientjes 342106808b08SLee Schermerhorn static ssize_t nr_hugepages_show(struct kobject *kobj, 342206808b08SLee Schermerhorn struct kobj_attribute *attr, char *buf) 342306808b08SLee Schermerhorn { 342406808b08SLee Schermerhorn return nr_hugepages_show_common(kobj, attr, buf); 342506808b08SLee Schermerhorn } 342606808b08SLee Schermerhorn 342706808b08SLee Schermerhorn static ssize_t nr_hugepages_store(struct kobject *kobj, 342806808b08SLee Schermerhorn struct kobj_attribute *attr, const char *buf, size_t len) 342906808b08SLee Schermerhorn { 3430238d3c13SDavid Rientjes return nr_hugepages_store_common(false, kobj, buf, len); 3431a3437870SNishanth Aravamudan } 3432a3437870SNishanth Aravamudan HSTATE_ATTR(nr_hugepages); 3433a3437870SNishanth Aravamudan 343406808b08SLee Schermerhorn #ifdef CONFIG_NUMA 343506808b08SLee Schermerhorn 343606808b08SLee Schermerhorn /* 343706808b08SLee Schermerhorn * hstate attribute for optionally mempolicy-based constraint on persistent 343806808b08SLee Schermerhorn * huge page alloc/free. 343906808b08SLee Schermerhorn */ 344006808b08SLee Schermerhorn static ssize_t nr_hugepages_mempolicy_show(struct kobject *kobj, 3441ae7a927dSJoe Perches struct kobj_attribute *attr, 3442ae7a927dSJoe Perches char *buf) 344306808b08SLee Schermerhorn { 344406808b08SLee Schermerhorn return nr_hugepages_show_common(kobj, attr, buf); 344506808b08SLee Schermerhorn } 344606808b08SLee Schermerhorn 344706808b08SLee Schermerhorn static ssize_t nr_hugepages_mempolicy_store(struct kobject *kobj, 344806808b08SLee Schermerhorn struct kobj_attribute *attr, const char *buf, size_t len) 344906808b08SLee Schermerhorn { 3450238d3c13SDavid Rientjes return nr_hugepages_store_common(true, kobj, buf, len); 345106808b08SLee Schermerhorn } 345206808b08SLee Schermerhorn HSTATE_ATTR(nr_hugepages_mempolicy); 345306808b08SLee Schermerhorn #endif 345406808b08SLee Schermerhorn 345506808b08SLee Schermerhorn 3456a3437870SNishanth Aravamudan static ssize_t nr_overcommit_hugepages_show(struct kobject *kobj, 3457a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 3458a3437870SNishanth Aravamudan { 34599a305230SLee Schermerhorn struct hstate *h = kobj_to_hstate(kobj, NULL); 3460ae7a927dSJoe Perches return sysfs_emit(buf, "%lu\n", h->nr_overcommit_huge_pages); 3461a3437870SNishanth Aravamudan } 3462adbe8726SEric B Munson 3463a3437870SNishanth Aravamudan static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, 3464a3437870SNishanth Aravamudan struct kobj_attribute *attr, const char *buf, size_t count) 3465a3437870SNishanth Aravamudan { 3466a3437870SNishanth Aravamudan int err; 3467a3437870SNishanth Aravamudan unsigned long input; 34689a305230SLee Schermerhorn struct hstate *h = kobj_to_hstate(kobj, NULL); 3469a3437870SNishanth Aravamudan 3470bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 3471adbe8726SEric B Munson return -EINVAL; 3472adbe8726SEric B Munson 34733dbb95f7SJingoo Han err = kstrtoul(buf, 10, &input); 3474a3437870SNishanth Aravamudan if (err) 347573ae31e5SEric B Munson return err; 3476a3437870SNishanth Aravamudan 3477db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 3478a3437870SNishanth Aravamudan h->nr_overcommit_huge_pages = input; 3479db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 3480a3437870SNishanth Aravamudan 3481a3437870SNishanth Aravamudan return count; 3482a3437870SNishanth Aravamudan } 3483a3437870SNishanth Aravamudan HSTATE_ATTR(nr_overcommit_hugepages); 3484a3437870SNishanth Aravamudan 3485a3437870SNishanth Aravamudan static ssize_t free_hugepages_show(struct kobject *kobj, 3486a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 3487a3437870SNishanth Aravamudan { 34889a305230SLee Schermerhorn struct hstate *h; 34899a305230SLee Schermerhorn unsigned long free_huge_pages; 34909a305230SLee Schermerhorn int nid; 34919a305230SLee Schermerhorn 34929a305230SLee Schermerhorn h = kobj_to_hstate(kobj, &nid); 34939a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) 34949a305230SLee Schermerhorn free_huge_pages = h->free_huge_pages; 34959a305230SLee Schermerhorn else 34969a305230SLee Schermerhorn free_huge_pages = h->free_huge_pages_node[nid]; 34979a305230SLee Schermerhorn 3498ae7a927dSJoe Perches return sysfs_emit(buf, "%lu\n", free_huge_pages); 3499a3437870SNishanth Aravamudan } 3500a3437870SNishanth Aravamudan HSTATE_ATTR_RO(free_hugepages); 3501a3437870SNishanth Aravamudan 3502a3437870SNishanth Aravamudan static ssize_t resv_hugepages_show(struct kobject *kobj, 3503a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 3504a3437870SNishanth Aravamudan { 35059a305230SLee Schermerhorn struct hstate *h = kobj_to_hstate(kobj, NULL); 3506ae7a927dSJoe Perches return sysfs_emit(buf, "%lu\n", h->resv_huge_pages); 3507a3437870SNishanth Aravamudan } 3508a3437870SNishanth Aravamudan HSTATE_ATTR_RO(resv_hugepages); 3509a3437870SNishanth Aravamudan 3510a3437870SNishanth Aravamudan static ssize_t surplus_hugepages_show(struct kobject *kobj, 3511a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 3512a3437870SNishanth Aravamudan { 35139a305230SLee Schermerhorn struct hstate *h; 35149a305230SLee Schermerhorn unsigned long surplus_huge_pages; 35159a305230SLee Schermerhorn int nid; 35169a305230SLee Schermerhorn 35179a305230SLee Schermerhorn h = kobj_to_hstate(kobj, &nid); 35189a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) 35199a305230SLee Schermerhorn surplus_huge_pages = h->surplus_huge_pages; 35209a305230SLee Schermerhorn else 35219a305230SLee Schermerhorn surplus_huge_pages = h->surplus_huge_pages_node[nid]; 35229a305230SLee Schermerhorn 3523ae7a927dSJoe Perches return sysfs_emit(buf, "%lu\n", surplus_huge_pages); 3524a3437870SNishanth Aravamudan } 3525a3437870SNishanth Aravamudan HSTATE_ATTR_RO(surplus_hugepages); 3526a3437870SNishanth Aravamudan 352779dfc695SMike Kravetz static ssize_t demote_store(struct kobject *kobj, 352879dfc695SMike Kravetz struct kobj_attribute *attr, const char *buf, size_t len) 352979dfc695SMike Kravetz { 353079dfc695SMike Kravetz unsigned long nr_demote; 353179dfc695SMike Kravetz unsigned long nr_available; 353279dfc695SMike Kravetz nodemask_t nodes_allowed, *n_mask; 353379dfc695SMike Kravetz struct hstate *h; 353479dfc695SMike Kravetz int err = 0; 353579dfc695SMike Kravetz int nid; 353679dfc695SMike Kravetz 353779dfc695SMike Kravetz err = kstrtoul(buf, 10, &nr_demote); 353879dfc695SMike Kravetz if (err) 353979dfc695SMike Kravetz return err; 354079dfc695SMike Kravetz h = kobj_to_hstate(kobj, &nid); 354179dfc695SMike Kravetz 354279dfc695SMike Kravetz if (nid != NUMA_NO_NODE) { 354379dfc695SMike Kravetz init_nodemask_of_node(&nodes_allowed, nid); 354479dfc695SMike Kravetz n_mask = &nodes_allowed; 354579dfc695SMike Kravetz } else { 354679dfc695SMike Kravetz n_mask = &node_states[N_MEMORY]; 354779dfc695SMike Kravetz } 354879dfc695SMike Kravetz 354979dfc695SMike Kravetz /* Synchronize with other sysfs operations modifying huge pages */ 355079dfc695SMike Kravetz mutex_lock(&h->resize_lock); 355179dfc695SMike Kravetz spin_lock_irq(&hugetlb_lock); 355279dfc695SMike Kravetz 355379dfc695SMike Kravetz while (nr_demote) { 355479dfc695SMike Kravetz /* 355579dfc695SMike Kravetz * Check for available pages to demote each time thorough the 355679dfc695SMike Kravetz * loop as demote_pool_huge_page will drop hugetlb_lock. 355779dfc695SMike Kravetz * 355879dfc695SMike Kravetz * NOTE: demote_pool_huge_page does not yet drop hugetlb_lock 355979dfc695SMike Kravetz * but will when full demote functionality is added in a later 356079dfc695SMike Kravetz * patch. 356179dfc695SMike Kravetz */ 356279dfc695SMike Kravetz if (nid != NUMA_NO_NODE) 356379dfc695SMike Kravetz nr_available = h->free_huge_pages_node[nid]; 356479dfc695SMike Kravetz else 356579dfc695SMike Kravetz nr_available = h->free_huge_pages; 356679dfc695SMike Kravetz nr_available -= h->resv_huge_pages; 356779dfc695SMike Kravetz if (!nr_available) 356879dfc695SMike Kravetz break; 356979dfc695SMike Kravetz 357079dfc695SMike Kravetz err = demote_pool_huge_page(h, n_mask); 357179dfc695SMike Kravetz if (err) 357279dfc695SMike Kravetz break; 357379dfc695SMike Kravetz 357479dfc695SMike Kravetz nr_demote--; 357579dfc695SMike Kravetz } 357679dfc695SMike Kravetz 357779dfc695SMike Kravetz spin_unlock_irq(&hugetlb_lock); 357879dfc695SMike Kravetz mutex_unlock(&h->resize_lock); 357979dfc695SMike Kravetz 358079dfc695SMike Kravetz if (err) 358179dfc695SMike Kravetz return err; 358279dfc695SMike Kravetz return len; 358379dfc695SMike Kravetz } 358479dfc695SMike Kravetz HSTATE_ATTR_WO(demote); 358579dfc695SMike Kravetz 358679dfc695SMike Kravetz static ssize_t demote_size_show(struct kobject *kobj, 358779dfc695SMike Kravetz struct kobj_attribute *attr, char *buf) 358879dfc695SMike Kravetz { 358979dfc695SMike Kravetz int nid; 359079dfc695SMike Kravetz struct hstate *h = kobj_to_hstate(kobj, &nid); 359179dfc695SMike Kravetz unsigned long demote_size = (PAGE_SIZE << h->demote_order) / SZ_1K; 359279dfc695SMike Kravetz 359379dfc695SMike Kravetz return sysfs_emit(buf, "%lukB\n", demote_size); 359479dfc695SMike Kravetz } 359579dfc695SMike Kravetz 359679dfc695SMike Kravetz static ssize_t demote_size_store(struct kobject *kobj, 359779dfc695SMike Kravetz struct kobj_attribute *attr, 359879dfc695SMike Kravetz const char *buf, size_t count) 359979dfc695SMike Kravetz { 360079dfc695SMike Kravetz struct hstate *h, *demote_hstate; 360179dfc695SMike Kravetz unsigned long demote_size; 360279dfc695SMike Kravetz unsigned int demote_order; 360379dfc695SMike Kravetz int nid; 360479dfc695SMike Kravetz 360579dfc695SMike Kravetz demote_size = (unsigned long)memparse(buf, NULL); 360679dfc695SMike Kravetz 360779dfc695SMike Kravetz demote_hstate = size_to_hstate(demote_size); 360879dfc695SMike Kravetz if (!demote_hstate) 360979dfc695SMike Kravetz return -EINVAL; 361079dfc695SMike Kravetz demote_order = demote_hstate->order; 3611a01f4390SMike Kravetz if (demote_order < HUGETLB_PAGE_ORDER) 3612a01f4390SMike Kravetz return -EINVAL; 361379dfc695SMike Kravetz 361479dfc695SMike Kravetz /* demote order must be smaller than hstate order */ 361579dfc695SMike Kravetz h = kobj_to_hstate(kobj, &nid); 361679dfc695SMike Kravetz if (demote_order >= h->order) 361779dfc695SMike Kravetz return -EINVAL; 361879dfc695SMike Kravetz 361979dfc695SMike Kravetz /* resize_lock synchronizes access to demote size and writes */ 362079dfc695SMike Kravetz mutex_lock(&h->resize_lock); 362179dfc695SMike Kravetz h->demote_order = demote_order; 362279dfc695SMike Kravetz mutex_unlock(&h->resize_lock); 362379dfc695SMike Kravetz 362479dfc695SMike Kravetz return count; 362579dfc695SMike Kravetz } 362679dfc695SMike Kravetz HSTATE_ATTR(demote_size); 362779dfc695SMike Kravetz 3628a3437870SNishanth Aravamudan static struct attribute *hstate_attrs[] = { 3629a3437870SNishanth Aravamudan &nr_hugepages_attr.attr, 3630a3437870SNishanth Aravamudan &nr_overcommit_hugepages_attr.attr, 3631a3437870SNishanth Aravamudan &free_hugepages_attr.attr, 3632a3437870SNishanth Aravamudan &resv_hugepages_attr.attr, 3633a3437870SNishanth Aravamudan &surplus_hugepages_attr.attr, 363406808b08SLee Schermerhorn #ifdef CONFIG_NUMA 363506808b08SLee Schermerhorn &nr_hugepages_mempolicy_attr.attr, 363606808b08SLee Schermerhorn #endif 3637a3437870SNishanth Aravamudan NULL, 3638a3437870SNishanth Aravamudan }; 3639a3437870SNishanth Aravamudan 364067e5ed96SArvind Yadav static const struct attribute_group hstate_attr_group = { 3641a3437870SNishanth Aravamudan .attrs = hstate_attrs, 3642a3437870SNishanth Aravamudan }; 3643a3437870SNishanth Aravamudan 364479dfc695SMike Kravetz static struct attribute *hstate_demote_attrs[] = { 364579dfc695SMike Kravetz &demote_size_attr.attr, 364679dfc695SMike Kravetz &demote_attr.attr, 364779dfc695SMike Kravetz NULL, 364879dfc695SMike Kravetz }; 364979dfc695SMike Kravetz 365079dfc695SMike Kravetz static const struct attribute_group hstate_demote_attr_group = { 365179dfc695SMike Kravetz .attrs = hstate_demote_attrs, 365279dfc695SMike Kravetz }; 365379dfc695SMike Kravetz 3654094e9539SJeff Mahoney static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent, 36559a305230SLee Schermerhorn struct kobject **hstate_kobjs, 365667e5ed96SArvind Yadav const struct attribute_group *hstate_attr_group) 3657a3437870SNishanth Aravamudan { 3658a3437870SNishanth Aravamudan int retval; 3659972dc4deSAneesh Kumar K.V int hi = hstate_index(h); 3660a3437870SNishanth Aravamudan 36619a305230SLee Schermerhorn hstate_kobjs[hi] = kobject_create_and_add(h->name, parent); 36629a305230SLee Schermerhorn if (!hstate_kobjs[hi]) 3663a3437870SNishanth Aravamudan return -ENOMEM; 3664a3437870SNishanth Aravamudan 36659a305230SLee Schermerhorn retval = sysfs_create_group(hstate_kobjs[hi], hstate_attr_group); 3666cc2205a6SMiaohe Lin if (retval) { 36679a305230SLee Schermerhorn kobject_put(hstate_kobjs[hi]); 3668cc2205a6SMiaohe Lin hstate_kobjs[hi] = NULL; 3669cc2205a6SMiaohe Lin } 3670a3437870SNishanth Aravamudan 367179dfc695SMike Kravetz if (h->demote_order) { 367279dfc695SMike Kravetz if (sysfs_create_group(hstate_kobjs[hi], 367379dfc695SMike Kravetz &hstate_demote_attr_group)) 367479dfc695SMike Kravetz pr_warn("HugeTLB unable to create demote interfaces for %s\n", h->name); 367579dfc695SMike Kravetz } 367679dfc695SMike Kravetz 3677a3437870SNishanth Aravamudan return retval; 3678a3437870SNishanth Aravamudan } 3679a3437870SNishanth Aravamudan 3680a3437870SNishanth Aravamudan static void __init hugetlb_sysfs_init(void) 3681a3437870SNishanth Aravamudan { 3682a3437870SNishanth Aravamudan struct hstate *h; 3683a3437870SNishanth Aravamudan int err; 3684a3437870SNishanth Aravamudan 3685a3437870SNishanth Aravamudan hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj); 3686a3437870SNishanth Aravamudan if (!hugepages_kobj) 3687a3437870SNishanth Aravamudan return; 3688a3437870SNishanth Aravamudan 3689a3437870SNishanth Aravamudan for_each_hstate(h) { 36909a305230SLee Schermerhorn err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, 36919a305230SLee Schermerhorn hstate_kobjs, &hstate_attr_group); 3692a3437870SNishanth Aravamudan if (err) 3693282f4214SMike Kravetz pr_err("HugeTLB: Unable to add hstate %s", h->name); 3694a3437870SNishanth Aravamudan } 3695a3437870SNishanth Aravamudan } 3696a3437870SNishanth Aravamudan 36979a305230SLee Schermerhorn #ifdef CONFIG_NUMA 36989a305230SLee Schermerhorn 36999a305230SLee Schermerhorn /* 37009a305230SLee Schermerhorn * node_hstate/s - associate per node hstate attributes, via their kobjects, 370110fbcf4cSKay Sievers * with node devices in node_devices[] using a parallel array. The array 370210fbcf4cSKay Sievers * index of a node device or _hstate == node id. 370310fbcf4cSKay Sievers * This is here to avoid any static dependency of the node device driver, in 37049a305230SLee Schermerhorn * the base kernel, on the hugetlb module. 37059a305230SLee Schermerhorn */ 37069a305230SLee Schermerhorn struct node_hstate { 37079a305230SLee Schermerhorn struct kobject *hugepages_kobj; 37089a305230SLee Schermerhorn struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; 37099a305230SLee Schermerhorn }; 3710b4e289a6SAlexander Kuleshov static struct node_hstate node_hstates[MAX_NUMNODES]; 37119a305230SLee Schermerhorn 37129a305230SLee Schermerhorn /* 371310fbcf4cSKay Sievers * A subset of global hstate attributes for node devices 37149a305230SLee Schermerhorn */ 37159a305230SLee Schermerhorn static struct attribute *per_node_hstate_attrs[] = { 37169a305230SLee Schermerhorn &nr_hugepages_attr.attr, 37179a305230SLee Schermerhorn &free_hugepages_attr.attr, 37189a305230SLee Schermerhorn &surplus_hugepages_attr.attr, 37199a305230SLee Schermerhorn NULL, 37209a305230SLee Schermerhorn }; 37219a305230SLee Schermerhorn 372267e5ed96SArvind Yadav static const struct attribute_group per_node_hstate_attr_group = { 37239a305230SLee Schermerhorn .attrs = per_node_hstate_attrs, 37249a305230SLee Schermerhorn }; 37259a305230SLee Schermerhorn 37269a305230SLee Schermerhorn /* 372710fbcf4cSKay Sievers * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj. 37289a305230SLee Schermerhorn * Returns node id via non-NULL nidp. 37299a305230SLee Schermerhorn */ 37309a305230SLee Schermerhorn static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) 37319a305230SLee Schermerhorn { 37329a305230SLee Schermerhorn int nid; 37339a305230SLee Schermerhorn 37349a305230SLee Schermerhorn for (nid = 0; nid < nr_node_ids; nid++) { 37359a305230SLee Schermerhorn struct node_hstate *nhs = &node_hstates[nid]; 37369a305230SLee Schermerhorn int i; 37379a305230SLee Schermerhorn for (i = 0; i < HUGE_MAX_HSTATE; i++) 37389a305230SLee Schermerhorn if (nhs->hstate_kobjs[i] == kobj) { 37399a305230SLee Schermerhorn if (nidp) 37409a305230SLee Schermerhorn *nidp = nid; 37419a305230SLee Schermerhorn return &hstates[i]; 37429a305230SLee Schermerhorn } 37439a305230SLee Schermerhorn } 37449a305230SLee Schermerhorn 37459a305230SLee Schermerhorn BUG(); 37469a305230SLee Schermerhorn return NULL; 37479a305230SLee Schermerhorn } 37489a305230SLee Schermerhorn 37499a305230SLee Schermerhorn /* 375010fbcf4cSKay Sievers * Unregister hstate attributes from a single node device. 37519a305230SLee Schermerhorn * No-op if no hstate attributes attached. 37529a305230SLee Schermerhorn */ 37533cd8b44fSClaudiu Ghioc static void hugetlb_unregister_node(struct node *node) 37549a305230SLee Schermerhorn { 37559a305230SLee Schermerhorn struct hstate *h; 375610fbcf4cSKay Sievers struct node_hstate *nhs = &node_hstates[node->dev.id]; 37579a305230SLee Schermerhorn 37589a305230SLee Schermerhorn if (!nhs->hugepages_kobj) 37599b5e5d0fSLee Schermerhorn return; /* no hstate attributes */ 37609a305230SLee Schermerhorn 3761972dc4deSAneesh Kumar K.V for_each_hstate(h) { 3762972dc4deSAneesh Kumar K.V int idx = hstate_index(h); 3763972dc4deSAneesh Kumar K.V if (nhs->hstate_kobjs[idx]) { 3764972dc4deSAneesh Kumar K.V kobject_put(nhs->hstate_kobjs[idx]); 3765972dc4deSAneesh Kumar K.V nhs->hstate_kobjs[idx] = NULL; 3766972dc4deSAneesh Kumar K.V } 37679a305230SLee Schermerhorn } 37689a305230SLee Schermerhorn 37699a305230SLee Schermerhorn kobject_put(nhs->hugepages_kobj); 37709a305230SLee Schermerhorn nhs->hugepages_kobj = NULL; 37719a305230SLee Schermerhorn } 37729a305230SLee Schermerhorn 37739a305230SLee Schermerhorn 37749a305230SLee Schermerhorn /* 377510fbcf4cSKay Sievers * Register hstate attributes for a single node device. 37769a305230SLee Schermerhorn * No-op if attributes already registered. 37779a305230SLee Schermerhorn */ 37783cd8b44fSClaudiu Ghioc static void hugetlb_register_node(struct node *node) 37799a305230SLee Schermerhorn { 37809a305230SLee Schermerhorn struct hstate *h; 378110fbcf4cSKay Sievers struct node_hstate *nhs = &node_hstates[node->dev.id]; 37829a305230SLee Schermerhorn int err; 37839a305230SLee Schermerhorn 37849a305230SLee Schermerhorn if (nhs->hugepages_kobj) 37859a305230SLee Schermerhorn return; /* already allocated */ 37869a305230SLee Schermerhorn 37879a305230SLee Schermerhorn nhs->hugepages_kobj = kobject_create_and_add("hugepages", 378810fbcf4cSKay Sievers &node->dev.kobj); 37899a305230SLee Schermerhorn if (!nhs->hugepages_kobj) 37909a305230SLee Schermerhorn return; 37919a305230SLee Schermerhorn 37929a305230SLee Schermerhorn for_each_hstate(h) { 37939a305230SLee Schermerhorn err = hugetlb_sysfs_add_hstate(h, nhs->hugepages_kobj, 37949a305230SLee Schermerhorn nhs->hstate_kobjs, 37959a305230SLee Schermerhorn &per_node_hstate_attr_group); 37969a305230SLee Schermerhorn if (err) { 3797282f4214SMike Kravetz pr_err("HugeTLB: Unable to add hstate %s for node %d\n", 379810fbcf4cSKay Sievers h->name, node->dev.id); 37999a305230SLee Schermerhorn hugetlb_unregister_node(node); 38009a305230SLee Schermerhorn break; 38019a305230SLee Schermerhorn } 38029a305230SLee Schermerhorn } 38039a305230SLee Schermerhorn } 38049a305230SLee Schermerhorn 38059a305230SLee Schermerhorn /* 38069b5e5d0fSLee Schermerhorn * hugetlb init time: register hstate attributes for all registered node 380710fbcf4cSKay Sievers * devices of nodes that have memory. All on-line nodes should have 380810fbcf4cSKay Sievers * registered their associated device by this time. 38099a305230SLee Schermerhorn */ 38107d9ca000SLuiz Capitulino static void __init hugetlb_register_all_nodes(void) 38119a305230SLee Schermerhorn { 38129a305230SLee Schermerhorn int nid; 38139a305230SLee Schermerhorn 38148cebfcd0SLai Jiangshan for_each_node_state(nid, N_MEMORY) { 38158732794bSWen Congyang struct node *node = node_devices[nid]; 381610fbcf4cSKay Sievers if (node->dev.id == nid) 38179a305230SLee Schermerhorn hugetlb_register_node(node); 38189a305230SLee Schermerhorn } 38199a305230SLee Schermerhorn 38209a305230SLee Schermerhorn /* 382110fbcf4cSKay Sievers * Let the node device driver know we're here so it can 38229a305230SLee Schermerhorn * [un]register hstate attributes on node hotplug. 38239a305230SLee Schermerhorn */ 38249a305230SLee Schermerhorn register_hugetlbfs_with_node(hugetlb_register_node, 38259a305230SLee Schermerhorn hugetlb_unregister_node); 38269a305230SLee Schermerhorn } 38279a305230SLee Schermerhorn #else /* !CONFIG_NUMA */ 38289a305230SLee Schermerhorn 38299a305230SLee Schermerhorn static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) 38309a305230SLee Schermerhorn { 38319a305230SLee Schermerhorn BUG(); 38329a305230SLee Schermerhorn if (nidp) 38339a305230SLee Schermerhorn *nidp = -1; 38349a305230SLee Schermerhorn return NULL; 38359a305230SLee Schermerhorn } 38369a305230SLee Schermerhorn 38379a305230SLee Schermerhorn static void hugetlb_register_all_nodes(void) { } 38389a305230SLee Schermerhorn 38399a305230SLee Schermerhorn #endif 38409a305230SLee Schermerhorn 3841a3437870SNishanth Aravamudan static int __init hugetlb_init(void) 3842a3437870SNishanth Aravamudan { 38438382d914SDavidlohr Bueso int i; 38448382d914SDavidlohr Bueso 3845d6995da3SMike Kravetz BUILD_BUG_ON(sizeof_field(struct page, private) * BITS_PER_BYTE < 3846d6995da3SMike Kravetz __NR_HPAGEFLAGS); 3847d6995da3SMike Kravetz 3848c2833a5bSMike Kravetz if (!hugepages_supported()) { 3849c2833a5bSMike Kravetz if (hugetlb_max_hstate || default_hstate_max_huge_pages) 3850c2833a5bSMike Kravetz pr_warn("HugeTLB: huge pages not supported, ignoring associated command-line parameters\n"); 38510ef89d25SBenjamin Herrenschmidt return 0; 3852d715cf80SLiam R. Howlett } 3853d715cf80SLiam R. Howlett 3854282f4214SMike Kravetz /* 3855282f4214SMike Kravetz * Make sure HPAGE_SIZE (HUGETLB_PAGE_ORDER) hstate exists. Some 3856282f4214SMike Kravetz * architectures depend on setup being done here. 3857282f4214SMike Kravetz */ 3858a3437870SNishanth Aravamudan hugetlb_add_hstate(HUGETLB_PAGE_ORDER); 3859282f4214SMike Kravetz if (!parsed_default_hugepagesz) { 3860282f4214SMike Kravetz /* 3861282f4214SMike Kravetz * If we did not parse a default huge page size, set 3862282f4214SMike Kravetz * default_hstate_idx to HPAGE_SIZE hstate. And, if the 3863282f4214SMike Kravetz * number of huge pages for this default size was implicitly 3864282f4214SMike Kravetz * specified, set that here as well. 3865282f4214SMike Kravetz * Note that the implicit setting will overwrite an explicit 3866282f4214SMike Kravetz * setting. A warning will be printed in this case. 3867282f4214SMike Kravetz */ 3868282f4214SMike Kravetz default_hstate_idx = hstate_index(size_to_hstate(HPAGE_SIZE)); 3869f8b74815SVaishali Thakkar if (default_hstate_max_huge_pages) { 3870282f4214SMike Kravetz if (default_hstate.max_huge_pages) { 3871282f4214SMike Kravetz char buf[32]; 3872282f4214SMike Kravetz 3873282f4214SMike Kravetz string_get_size(huge_page_size(&default_hstate), 3874282f4214SMike Kravetz 1, STRING_UNITS_2, buf, 32); 3875282f4214SMike Kravetz pr_warn("HugeTLB: Ignoring hugepages=%lu associated with %s page size\n", 3876282f4214SMike Kravetz default_hstate.max_huge_pages, buf); 3877282f4214SMike Kravetz pr_warn("HugeTLB: Using hugepages=%lu for number of default huge pages\n", 3878282f4214SMike Kravetz default_hstate_max_huge_pages); 3879282f4214SMike Kravetz } 3880282f4214SMike Kravetz default_hstate.max_huge_pages = 3881282f4214SMike Kravetz default_hstate_max_huge_pages; 3882282f4214SMike Kravetz } 3883f8b74815SVaishali Thakkar } 3884a3437870SNishanth Aravamudan 3885cf11e85fSRoman Gushchin hugetlb_cma_check(); 3886a3437870SNishanth Aravamudan hugetlb_init_hstates(); 3887aa888a74SAndi Kleen gather_bootmem_prealloc(); 3888a3437870SNishanth Aravamudan report_hugepages(); 3889a3437870SNishanth Aravamudan 3890a3437870SNishanth Aravamudan hugetlb_sysfs_init(); 38919a305230SLee Schermerhorn hugetlb_register_all_nodes(); 38927179e7bfSJianguo Wu hugetlb_cgroup_file_init(); 38939a305230SLee Schermerhorn 38948382d914SDavidlohr Bueso #ifdef CONFIG_SMP 38958382d914SDavidlohr Bueso num_fault_mutexes = roundup_pow_of_two(8 * num_possible_cpus()); 38968382d914SDavidlohr Bueso #else 38978382d914SDavidlohr Bueso num_fault_mutexes = 1; 38988382d914SDavidlohr Bueso #endif 3899c672c7f2SMike Kravetz hugetlb_fault_mutex_table = 39006da2ec56SKees Cook kmalloc_array(num_fault_mutexes, sizeof(struct mutex), 39016da2ec56SKees Cook GFP_KERNEL); 3902c672c7f2SMike Kravetz BUG_ON(!hugetlb_fault_mutex_table); 39038382d914SDavidlohr Bueso 39048382d914SDavidlohr Bueso for (i = 0; i < num_fault_mutexes; i++) 3905c672c7f2SMike Kravetz mutex_init(&hugetlb_fault_mutex_table[i]); 3906a3437870SNishanth Aravamudan return 0; 3907a3437870SNishanth Aravamudan } 39083e89e1c5SPaul Gortmaker subsys_initcall(hugetlb_init); 3909a3437870SNishanth Aravamudan 3910ae94da89SMike Kravetz /* Overwritten by architectures with more huge page sizes */ 3911ae94da89SMike Kravetz bool __init __attribute((weak)) arch_hugetlb_valid_size(unsigned long size) 39129fee021dSVaishali Thakkar { 3913ae94da89SMike Kravetz return size == HPAGE_SIZE; 39149fee021dSVaishali Thakkar } 39159fee021dSVaishali Thakkar 3916d00181b9SKirill A. Shutemov void __init hugetlb_add_hstate(unsigned int order) 3917a3437870SNishanth Aravamudan { 3918a3437870SNishanth Aravamudan struct hstate *h; 39198faa8b07SAndi Kleen unsigned long i; 39208faa8b07SAndi Kleen 3921a3437870SNishanth Aravamudan if (size_to_hstate(PAGE_SIZE << order)) { 3922a3437870SNishanth Aravamudan return; 3923a3437870SNishanth Aravamudan } 392447d38344SAneesh Kumar K.V BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE); 3925a3437870SNishanth Aravamudan BUG_ON(order == 0); 392647d38344SAneesh Kumar K.V h = &hstates[hugetlb_max_hstate++]; 392729383967SMike Kravetz mutex_init(&h->resize_lock); 3928a3437870SNishanth Aravamudan h->order = order; 3929aca78307SMiaohe Lin h->mask = ~(huge_page_size(h) - 1); 39308faa8b07SAndi Kleen for (i = 0; i < MAX_NUMNODES; ++i) 39318faa8b07SAndi Kleen INIT_LIST_HEAD(&h->hugepage_freelists[i]); 39320edaecfaSAneesh Kumar K.V INIT_LIST_HEAD(&h->hugepage_activelist); 393354f18d35SAndrew Morton h->next_nid_to_alloc = first_memory_node; 393454f18d35SAndrew Morton h->next_nid_to_free = first_memory_node; 3935a3437870SNishanth Aravamudan snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB", 3936a3437870SNishanth Aravamudan huge_page_size(h)/1024); 393777490587SMuchun Song hugetlb_vmemmap_init(h); 39388faa8b07SAndi Kleen 3939a3437870SNishanth Aravamudan parsed_hstate = h; 3940a3437870SNishanth Aravamudan } 3941a3437870SNishanth Aravamudan 3942282f4214SMike Kravetz /* 3943282f4214SMike Kravetz * hugepages command line processing 3944282f4214SMike Kravetz * hugepages normally follows a valid hugepagsz or default_hugepagsz 3945282f4214SMike Kravetz * specification. If not, ignore the hugepages value. hugepages can also 3946282f4214SMike Kravetz * be the first huge page command line option in which case it implicitly 3947282f4214SMike Kravetz * specifies the number of huge pages for the default size. 3948282f4214SMike Kravetz */ 3949282f4214SMike Kravetz static int __init hugepages_setup(char *s) 3950a3437870SNishanth Aravamudan { 3951a3437870SNishanth Aravamudan unsigned long *mhp; 39528faa8b07SAndi Kleen static unsigned long *last_mhp; 3953a3437870SNishanth Aravamudan 39549fee021dSVaishali Thakkar if (!parsed_valid_hugepagesz) { 3955282f4214SMike Kravetz pr_warn("HugeTLB: hugepages=%s does not follow a valid hugepagesz, ignoring\n", s); 39569fee021dSVaishali Thakkar parsed_valid_hugepagesz = true; 3957282f4214SMike Kravetz return 0; 39589fee021dSVaishali Thakkar } 3959282f4214SMike Kravetz 3960a3437870SNishanth Aravamudan /* 3961282f4214SMike Kravetz * !hugetlb_max_hstate means we haven't parsed a hugepagesz= parameter 3962282f4214SMike Kravetz * yet, so this hugepages= parameter goes to the "default hstate". 3963282f4214SMike Kravetz * Otherwise, it goes with the previously parsed hugepagesz or 3964282f4214SMike Kravetz * default_hugepagesz. 3965a3437870SNishanth Aravamudan */ 39669fee021dSVaishali Thakkar else if (!hugetlb_max_hstate) 3967a3437870SNishanth Aravamudan mhp = &default_hstate_max_huge_pages; 3968a3437870SNishanth Aravamudan else 3969a3437870SNishanth Aravamudan mhp = &parsed_hstate->max_huge_pages; 3970a3437870SNishanth Aravamudan 39718faa8b07SAndi Kleen if (mhp == last_mhp) { 3972282f4214SMike Kravetz pr_warn("HugeTLB: hugepages= specified twice without interleaving hugepagesz=, ignoring hugepages=%s\n", s); 3973282f4214SMike Kravetz return 0; 39748faa8b07SAndi Kleen } 39758faa8b07SAndi Kleen 3976a3437870SNishanth Aravamudan if (sscanf(s, "%lu", mhp) <= 0) 3977a3437870SNishanth Aravamudan *mhp = 0; 3978a3437870SNishanth Aravamudan 39798faa8b07SAndi Kleen /* 39808faa8b07SAndi Kleen * Global state is always initialized later in hugetlb_init. 398104adbc3fSMiaohe Lin * But we need to allocate gigantic hstates here early to still 39828faa8b07SAndi Kleen * use the bootmem allocator. 39838faa8b07SAndi Kleen */ 398404adbc3fSMiaohe Lin if (hugetlb_max_hstate && hstate_is_gigantic(parsed_hstate)) 39858faa8b07SAndi Kleen hugetlb_hstate_alloc_pages(parsed_hstate); 39868faa8b07SAndi Kleen 39878faa8b07SAndi Kleen last_mhp = mhp; 39888faa8b07SAndi Kleen 3989a3437870SNishanth Aravamudan return 1; 3990a3437870SNishanth Aravamudan } 3991282f4214SMike Kravetz __setup("hugepages=", hugepages_setup); 3992e11bfbfcSNick Piggin 3993282f4214SMike Kravetz /* 3994282f4214SMike Kravetz * hugepagesz command line processing 3995282f4214SMike Kravetz * A specific huge page size can only be specified once with hugepagesz. 3996282f4214SMike Kravetz * hugepagesz is followed by hugepages on the command line. The global 3997282f4214SMike Kravetz * variable 'parsed_valid_hugepagesz' is used to determine if prior 3998282f4214SMike Kravetz * hugepagesz argument was valid. 3999282f4214SMike Kravetz */ 4000359f2544SMike Kravetz static int __init hugepagesz_setup(char *s) 4001e11bfbfcSNick Piggin { 4002359f2544SMike Kravetz unsigned long size; 4003282f4214SMike Kravetz struct hstate *h; 4004282f4214SMike Kravetz 4005282f4214SMike Kravetz parsed_valid_hugepagesz = false; 4006359f2544SMike Kravetz size = (unsigned long)memparse(s, NULL); 4007359f2544SMike Kravetz 4008359f2544SMike Kravetz if (!arch_hugetlb_valid_size(size)) { 4009282f4214SMike Kravetz pr_err("HugeTLB: unsupported hugepagesz=%s\n", s); 4010359f2544SMike Kravetz return 0; 4011359f2544SMike Kravetz } 4012359f2544SMike Kravetz 4013282f4214SMike Kravetz h = size_to_hstate(size); 4014282f4214SMike Kravetz if (h) { 4015282f4214SMike Kravetz /* 4016282f4214SMike Kravetz * hstate for this size already exists. This is normally 4017282f4214SMike Kravetz * an error, but is allowed if the existing hstate is the 4018282f4214SMike Kravetz * default hstate. More specifically, it is only allowed if 4019282f4214SMike Kravetz * the number of huge pages for the default hstate was not 4020282f4214SMike Kravetz * previously specified. 4021282f4214SMike Kravetz */ 4022282f4214SMike Kravetz if (!parsed_default_hugepagesz || h != &default_hstate || 4023282f4214SMike Kravetz default_hstate.max_huge_pages) { 4024282f4214SMike Kravetz pr_warn("HugeTLB: hugepagesz=%s specified twice, ignoring\n", s); 402538237830SMike Kravetz return 0; 402638237830SMike Kravetz } 402738237830SMike Kravetz 4028282f4214SMike Kravetz /* 4029282f4214SMike Kravetz * No need to call hugetlb_add_hstate() as hstate already 4030282f4214SMike Kravetz * exists. But, do set parsed_hstate so that a following 4031282f4214SMike Kravetz * hugepages= parameter will be applied to this hstate. 4032282f4214SMike Kravetz */ 4033282f4214SMike Kravetz parsed_hstate = h; 4034282f4214SMike Kravetz parsed_valid_hugepagesz = true; 4035e11bfbfcSNick Piggin return 1; 4036e11bfbfcSNick Piggin } 4037282f4214SMike Kravetz 4038359f2544SMike Kravetz hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT); 4039282f4214SMike Kravetz parsed_valid_hugepagesz = true; 4040359f2544SMike Kravetz return 1; 4041359f2544SMike Kravetz } 4042359f2544SMike Kravetz __setup("hugepagesz=", hugepagesz_setup); 4043359f2544SMike Kravetz 4044282f4214SMike Kravetz /* 4045282f4214SMike Kravetz * default_hugepagesz command line input 4046282f4214SMike Kravetz * Only one instance of default_hugepagesz allowed on command line. 4047282f4214SMike Kravetz */ 4048ae94da89SMike Kravetz static int __init default_hugepagesz_setup(char *s) 4049e11bfbfcSNick Piggin { 4050ae94da89SMike Kravetz unsigned long size; 4051ae94da89SMike Kravetz 4052282f4214SMike Kravetz parsed_valid_hugepagesz = false; 4053282f4214SMike Kravetz if (parsed_default_hugepagesz) { 4054282f4214SMike Kravetz pr_err("HugeTLB: default_hugepagesz previously specified, ignoring %s\n", s); 4055282f4214SMike Kravetz return 0; 4056282f4214SMike Kravetz } 4057282f4214SMike Kravetz 4058282f4214SMike Kravetz size = (unsigned long)memparse(s, NULL); 4059282f4214SMike Kravetz 4060282f4214SMike Kravetz if (!arch_hugetlb_valid_size(size)) { 4061282f4214SMike Kravetz pr_err("HugeTLB: unsupported default_hugepagesz=%s\n", s); 4062282f4214SMike Kravetz return 0; 4063282f4214SMike Kravetz } 4064282f4214SMike Kravetz 4065282f4214SMike Kravetz hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT); 4066282f4214SMike Kravetz parsed_valid_hugepagesz = true; 4067282f4214SMike Kravetz parsed_default_hugepagesz = true; 4068282f4214SMike Kravetz default_hstate_idx = hstate_index(size_to_hstate(size)); 4069282f4214SMike Kravetz 4070282f4214SMike Kravetz /* 4071282f4214SMike Kravetz * The number of default huge pages (for this size) could have been 4072282f4214SMike Kravetz * specified as the first hugetlb parameter: hugepages=X. If so, 4073282f4214SMike Kravetz * then default_hstate_max_huge_pages is set. If the default huge 4074282f4214SMike Kravetz * page size is gigantic (>= MAX_ORDER), then the pages must be 4075282f4214SMike Kravetz * allocated here from bootmem allocator. 4076282f4214SMike Kravetz */ 4077282f4214SMike Kravetz if (default_hstate_max_huge_pages) { 4078282f4214SMike Kravetz default_hstate.max_huge_pages = default_hstate_max_huge_pages; 4079282f4214SMike Kravetz if (hstate_is_gigantic(&default_hstate)) 4080282f4214SMike Kravetz hugetlb_hstate_alloc_pages(&default_hstate); 4081282f4214SMike Kravetz default_hstate_max_huge_pages = 0; 4082282f4214SMike Kravetz } 4083282f4214SMike Kravetz 4084e11bfbfcSNick Piggin return 1; 4085e11bfbfcSNick Piggin } 4086ae94da89SMike Kravetz __setup("default_hugepagesz=", default_hugepagesz_setup); 4087a3437870SNishanth Aravamudan 40888ca39e68SMuchun Song static unsigned int allowed_mems_nr(struct hstate *h) 40898a213460SNishanth Aravamudan { 40908a213460SNishanth Aravamudan int node; 40918a213460SNishanth Aravamudan unsigned int nr = 0; 40928ca39e68SMuchun Song nodemask_t *mpol_allowed; 40938ca39e68SMuchun Song unsigned int *array = h->free_huge_pages_node; 40948ca39e68SMuchun Song gfp_t gfp_mask = htlb_alloc_mask(h); 40958a213460SNishanth Aravamudan 40968ca39e68SMuchun Song mpol_allowed = policy_nodemask_current(gfp_mask); 40978ca39e68SMuchun Song 40988ca39e68SMuchun Song for_each_node_mask(node, cpuset_current_mems_allowed) { 4099c93b0a99SJiapeng Zhong if (!mpol_allowed || node_isset(node, *mpol_allowed)) 41008a213460SNishanth Aravamudan nr += array[node]; 41018ca39e68SMuchun Song } 41028a213460SNishanth Aravamudan 41038a213460SNishanth Aravamudan return nr; 41048a213460SNishanth Aravamudan } 41058a213460SNishanth Aravamudan 41068a213460SNishanth Aravamudan #ifdef CONFIG_SYSCTL 410717743798SMuchun Song static int proc_hugetlb_doulongvec_minmax(struct ctl_table *table, int write, 410817743798SMuchun Song void *buffer, size_t *length, 410917743798SMuchun Song loff_t *ppos, unsigned long *out) 411017743798SMuchun Song { 411117743798SMuchun Song struct ctl_table dup_table; 411217743798SMuchun Song 411317743798SMuchun Song /* 411417743798SMuchun Song * In order to avoid races with __do_proc_doulongvec_minmax(), we 411517743798SMuchun Song * can duplicate the @table and alter the duplicate of it. 411617743798SMuchun Song */ 411717743798SMuchun Song dup_table = *table; 411817743798SMuchun Song dup_table.data = out; 411917743798SMuchun Song 412017743798SMuchun Song return proc_doulongvec_minmax(&dup_table, write, buffer, length, ppos); 412117743798SMuchun Song } 412217743798SMuchun Song 412306808b08SLee Schermerhorn static int hugetlb_sysctl_handler_common(bool obey_mempolicy, 412406808b08SLee Schermerhorn struct ctl_table *table, int write, 412532927393SChristoph Hellwig void *buffer, size_t *length, loff_t *ppos) 41261da177e4SLinus Torvalds { 4127e5ff2159SAndi Kleen struct hstate *h = &default_hstate; 4128238d3c13SDavid Rientjes unsigned long tmp = h->max_huge_pages; 412908d4a246SMichal Hocko int ret; 4130e5ff2159SAndi Kleen 4131457c1b27SNishanth Aravamudan if (!hugepages_supported()) 413286613628SJan Stancek return -EOPNOTSUPP; 4133457c1b27SNishanth Aravamudan 413417743798SMuchun Song ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos, 413517743798SMuchun Song &tmp); 413608d4a246SMichal Hocko if (ret) 413708d4a246SMichal Hocko goto out; 4138e5ff2159SAndi Kleen 4139238d3c13SDavid Rientjes if (write) 4140238d3c13SDavid Rientjes ret = __nr_hugepages_store_common(obey_mempolicy, h, 4141238d3c13SDavid Rientjes NUMA_NO_NODE, tmp, *length); 414208d4a246SMichal Hocko out: 414308d4a246SMichal Hocko return ret; 41441da177e4SLinus Torvalds } 4145396faf03SMel Gorman 414606808b08SLee Schermerhorn int hugetlb_sysctl_handler(struct ctl_table *table, int write, 414732927393SChristoph Hellwig void *buffer, size_t *length, loff_t *ppos) 414806808b08SLee Schermerhorn { 414906808b08SLee Schermerhorn 415006808b08SLee Schermerhorn return hugetlb_sysctl_handler_common(false, table, write, 415106808b08SLee Schermerhorn buffer, length, ppos); 415206808b08SLee Schermerhorn } 415306808b08SLee Schermerhorn 415406808b08SLee Schermerhorn #ifdef CONFIG_NUMA 415506808b08SLee Schermerhorn int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, 415632927393SChristoph Hellwig void *buffer, size_t *length, loff_t *ppos) 415706808b08SLee Schermerhorn { 415806808b08SLee Schermerhorn return hugetlb_sysctl_handler_common(true, table, write, 415906808b08SLee Schermerhorn buffer, length, ppos); 416006808b08SLee Schermerhorn } 416106808b08SLee Schermerhorn #endif /* CONFIG_NUMA */ 416206808b08SLee Schermerhorn 4163a3d0c6aaSNishanth Aravamudan int hugetlb_overcommit_handler(struct ctl_table *table, int write, 416432927393SChristoph Hellwig void *buffer, size_t *length, loff_t *ppos) 4165a3d0c6aaSNishanth Aravamudan { 4166a5516438SAndi Kleen struct hstate *h = &default_hstate; 4167e5ff2159SAndi Kleen unsigned long tmp; 416808d4a246SMichal Hocko int ret; 4169e5ff2159SAndi Kleen 4170457c1b27SNishanth Aravamudan if (!hugepages_supported()) 417186613628SJan Stancek return -EOPNOTSUPP; 4172457c1b27SNishanth Aravamudan 4173e5ff2159SAndi Kleen tmp = h->nr_overcommit_huge_pages; 4174e5ff2159SAndi Kleen 4175bae7f4aeSLuiz Capitulino if (write && hstate_is_gigantic(h)) 4176adbe8726SEric B Munson return -EINVAL; 4177adbe8726SEric B Munson 417817743798SMuchun Song ret = proc_hugetlb_doulongvec_minmax(table, write, buffer, length, ppos, 417917743798SMuchun Song &tmp); 418008d4a246SMichal Hocko if (ret) 418108d4a246SMichal Hocko goto out; 4182e5ff2159SAndi Kleen 4183e5ff2159SAndi Kleen if (write) { 4184db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 4185e5ff2159SAndi Kleen h->nr_overcommit_huge_pages = tmp; 4186db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 4187e5ff2159SAndi Kleen } 418808d4a246SMichal Hocko out: 418908d4a246SMichal Hocko return ret; 4190a3d0c6aaSNishanth Aravamudan } 4191a3d0c6aaSNishanth Aravamudan 41921da177e4SLinus Torvalds #endif /* CONFIG_SYSCTL */ 41931da177e4SLinus Torvalds 4194e1759c21SAlexey Dobriyan void hugetlb_report_meminfo(struct seq_file *m) 41951da177e4SLinus Torvalds { 4196fcb2b0c5SRoman Gushchin struct hstate *h; 4197fcb2b0c5SRoman Gushchin unsigned long total = 0; 4198fcb2b0c5SRoman Gushchin 4199457c1b27SNishanth Aravamudan if (!hugepages_supported()) 4200457c1b27SNishanth Aravamudan return; 4201fcb2b0c5SRoman Gushchin 4202fcb2b0c5SRoman Gushchin for_each_hstate(h) { 4203fcb2b0c5SRoman Gushchin unsigned long count = h->nr_huge_pages; 4204fcb2b0c5SRoman Gushchin 4205aca78307SMiaohe Lin total += huge_page_size(h) * count; 4206fcb2b0c5SRoman Gushchin 4207fcb2b0c5SRoman Gushchin if (h == &default_hstate) 4208e1759c21SAlexey Dobriyan seq_printf(m, 42091da177e4SLinus Torvalds "HugePages_Total: %5lu\n" 42101da177e4SLinus Torvalds "HugePages_Free: %5lu\n" 4211b45b5bd6SDavid Gibson "HugePages_Rsvd: %5lu\n" 42127893d1d5SAdam Litke "HugePages_Surp: %5lu\n" 42134f98a2feSRik van Riel "Hugepagesize: %8lu kB\n", 4214fcb2b0c5SRoman Gushchin count, 4215a5516438SAndi Kleen h->free_huge_pages, 4216a5516438SAndi Kleen h->resv_huge_pages, 4217a5516438SAndi Kleen h->surplus_huge_pages, 4218aca78307SMiaohe Lin huge_page_size(h) / SZ_1K); 4219fcb2b0c5SRoman Gushchin } 4220fcb2b0c5SRoman Gushchin 4221aca78307SMiaohe Lin seq_printf(m, "Hugetlb: %8lu kB\n", total / SZ_1K); 42221da177e4SLinus Torvalds } 42231da177e4SLinus Torvalds 42247981593bSJoe Perches int hugetlb_report_node_meminfo(char *buf, int len, int nid) 42251da177e4SLinus Torvalds { 4226a5516438SAndi Kleen struct hstate *h = &default_hstate; 42277981593bSJoe Perches 4228457c1b27SNishanth Aravamudan if (!hugepages_supported()) 4229457c1b27SNishanth Aravamudan return 0; 42307981593bSJoe Perches 42317981593bSJoe Perches return sysfs_emit_at(buf, len, 42321da177e4SLinus Torvalds "Node %d HugePages_Total: %5u\n" 4233a1de0919SNishanth Aravamudan "Node %d HugePages_Free: %5u\n" 4234a1de0919SNishanth Aravamudan "Node %d HugePages_Surp: %5u\n", 4235a5516438SAndi Kleen nid, h->nr_huge_pages_node[nid], 4236a5516438SAndi Kleen nid, h->free_huge_pages_node[nid], 4237a5516438SAndi Kleen nid, h->surplus_huge_pages_node[nid]); 42381da177e4SLinus Torvalds } 42391da177e4SLinus Torvalds 4240949f7ec5SDavid Rientjes void hugetlb_show_meminfo(void) 4241949f7ec5SDavid Rientjes { 4242949f7ec5SDavid Rientjes struct hstate *h; 4243949f7ec5SDavid Rientjes int nid; 4244949f7ec5SDavid Rientjes 4245457c1b27SNishanth Aravamudan if (!hugepages_supported()) 4246457c1b27SNishanth Aravamudan return; 4247457c1b27SNishanth Aravamudan 4248949f7ec5SDavid Rientjes for_each_node_state(nid, N_MEMORY) 4249949f7ec5SDavid Rientjes for_each_hstate(h) 4250949f7ec5SDavid Rientjes pr_info("Node %d hugepages_total=%u hugepages_free=%u hugepages_surp=%u hugepages_size=%lukB\n", 4251949f7ec5SDavid Rientjes nid, 4252949f7ec5SDavid Rientjes h->nr_huge_pages_node[nid], 4253949f7ec5SDavid Rientjes h->free_huge_pages_node[nid], 4254949f7ec5SDavid Rientjes h->surplus_huge_pages_node[nid], 4255aca78307SMiaohe Lin huge_page_size(h) / SZ_1K); 4256949f7ec5SDavid Rientjes } 4257949f7ec5SDavid Rientjes 42585d317b2bSNaoya Horiguchi void hugetlb_report_usage(struct seq_file *m, struct mm_struct *mm) 42595d317b2bSNaoya Horiguchi { 42605d317b2bSNaoya Horiguchi seq_printf(m, "HugetlbPages:\t%8lu kB\n", 42615d317b2bSNaoya Horiguchi atomic_long_read(&mm->hugetlb_usage) << (PAGE_SHIFT - 10)); 42625d317b2bSNaoya Horiguchi } 42635d317b2bSNaoya Horiguchi 42641da177e4SLinus Torvalds /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ 42651da177e4SLinus Torvalds unsigned long hugetlb_total_pages(void) 42661da177e4SLinus Torvalds { 4267d0028588SWanpeng Li struct hstate *h; 4268d0028588SWanpeng Li unsigned long nr_total_pages = 0; 4269d0028588SWanpeng Li 4270d0028588SWanpeng Li for_each_hstate(h) 4271d0028588SWanpeng Li nr_total_pages += h->nr_huge_pages * pages_per_huge_page(h); 4272d0028588SWanpeng Li return nr_total_pages; 42731da177e4SLinus Torvalds } 42741da177e4SLinus Torvalds 4275a5516438SAndi Kleen static int hugetlb_acct_memory(struct hstate *h, long delta) 4276fc1b8a73SMel Gorman { 4277fc1b8a73SMel Gorman int ret = -ENOMEM; 4278fc1b8a73SMel Gorman 42790aa7f354SMiaohe Lin if (!delta) 42800aa7f354SMiaohe Lin return 0; 42810aa7f354SMiaohe Lin 4282db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 4283fc1b8a73SMel Gorman /* 4284fc1b8a73SMel Gorman * When cpuset is configured, it breaks the strict hugetlb page 4285fc1b8a73SMel Gorman * reservation as the accounting is done on a global variable. Such 4286fc1b8a73SMel Gorman * reservation is completely rubbish in the presence of cpuset because 4287fc1b8a73SMel Gorman * the reservation is not checked against page availability for the 4288fc1b8a73SMel Gorman * current cpuset. Application can still potentially OOM'ed by kernel 4289fc1b8a73SMel Gorman * with lack of free htlb page in cpuset that the task is in. 4290fc1b8a73SMel Gorman * Attempt to enforce strict accounting with cpuset is almost 4291fc1b8a73SMel Gorman * impossible (or too ugly) because cpuset is too fluid that 4292fc1b8a73SMel Gorman * task or memory node can be dynamically moved between cpusets. 4293fc1b8a73SMel Gorman * 4294fc1b8a73SMel Gorman * The change of semantics for shared hugetlb mapping with cpuset is 4295fc1b8a73SMel Gorman * undesirable. However, in order to preserve some of the semantics, 4296fc1b8a73SMel Gorman * we fall back to check against current free page availability as 4297fc1b8a73SMel Gorman * a best attempt and hopefully to minimize the impact of changing 4298fc1b8a73SMel Gorman * semantics that cpuset has. 42998ca39e68SMuchun Song * 43008ca39e68SMuchun Song * Apart from cpuset, we also have memory policy mechanism that 43018ca39e68SMuchun Song * also determines from which node the kernel will allocate memory 43028ca39e68SMuchun Song * in a NUMA system. So similar to cpuset, we also should consider 43038ca39e68SMuchun Song * the memory policy of the current task. Similar to the description 43048ca39e68SMuchun Song * above. 4305fc1b8a73SMel Gorman */ 4306fc1b8a73SMel Gorman if (delta > 0) { 4307a5516438SAndi Kleen if (gather_surplus_pages(h, delta) < 0) 4308fc1b8a73SMel Gorman goto out; 4309fc1b8a73SMel Gorman 43108ca39e68SMuchun Song if (delta > allowed_mems_nr(h)) { 4311a5516438SAndi Kleen return_unused_surplus_pages(h, delta); 4312fc1b8a73SMel Gorman goto out; 4313fc1b8a73SMel Gorman } 4314fc1b8a73SMel Gorman } 4315fc1b8a73SMel Gorman 4316fc1b8a73SMel Gorman ret = 0; 4317fc1b8a73SMel Gorman if (delta < 0) 4318a5516438SAndi Kleen return_unused_surplus_pages(h, (unsigned long) -delta); 4319fc1b8a73SMel Gorman 4320fc1b8a73SMel Gorman out: 4321db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 4322fc1b8a73SMel Gorman return ret; 4323fc1b8a73SMel Gorman } 4324fc1b8a73SMel Gorman 432584afd99bSAndy Whitcroft static void hugetlb_vm_op_open(struct vm_area_struct *vma) 432684afd99bSAndy Whitcroft { 4327f522c3acSJoonsoo Kim struct resv_map *resv = vma_resv_map(vma); 432884afd99bSAndy Whitcroft 432984afd99bSAndy Whitcroft /* 433084afd99bSAndy Whitcroft * This new VMA should share its siblings reservation map if present. 433184afd99bSAndy Whitcroft * The VMA will only ever have a valid reservation map pointer where 433284afd99bSAndy Whitcroft * it is being copied for another still existing VMA. As that VMA 433325985edcSLucas De Marchi * has a reference to the reservation map it cannot disappear until 433484afd99bSAndy Whitcroft * after this open call completes. It is therefore safe to take a 433584afd99bSAndy Whitcroft * new reference here without additional locking. 433684afd99bSAndy Whitcroft */ 433709a26e83SMike Kravetz if (resv && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { 433809a26e83SMike Kravetz resv_map_dup_hugetlb_cgroup_uncharge_info(resv); 4339f522c3acSJoonsoo Kim kref_get(&resv->refs); 434084afd99bSAndy Whitcroft } 434109a26e83SMike Kravetz } 434284afd99bSAndy Whitcroft 4343a1e78772SMel Gorman static void hugetlb_vm_op_close(struct vm_area_struct *vma) 4344a1e78772SMel Gorman { 4345a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 4346f522c3acSJoonsoo Kim struct resv_map *resv = vma_resv_map(vma); 434790481622SDavid Gibson struct hugepage_subpool *spool = subpool_vma(vma); 43484e35f483SJoonsoo Kim unsigned long reserve, start, end; 43491c5ecae3SMike Kravetz long gbl_reserve; 435084afd99bSAndy Whitcroft 43514e35f483SJoonsoo Kim if (!resv || !is_vma_resv_set(vma, HPAGE_RESV_OWNER)) 43524e35f483SJoonsoo Kim return; 43534e35f483SJoonsoo Kim 4354a5516438SAndi Kleen start = vma_hugecache_offset(h, vma, vma->vm_start); 4355a5516438SAndi Kleen end = vma_hugecache_offset(h, vma, vma->vm_end); 435684afd99bSAndy Whitcroft 43574e35f483SJoonsoo Kim reserve = (end - start) - region_count(resv, start, end); 4358e9fe92aeSMina Almasry hugetlb_cgroup_uncharge_counter(resv, start, end); 43597251ff78SAdam Litke if (reserve) { 43601c5ecae3SMike Kravetz /* 43611c5ecae3SMike Kravetz * Decrement reserve counts. The global reserve count may be 43621c5ecae3SMike Kravetz * adjusted if the subpool has a minimum size. 43631c5ecae3SMike Kravetz */ 43641c5ecae3SMike Kravetz gbl_reserve = hugepage_subpool_put_pages(spool, reserve); 43651c5ecae3SMike Kravetz hugetlb_acct_memory(h, -gbl_reserve); 43667251ff78SAdam Litke } 4367e9fe92aeSMina Almasry 4368e9fe92aeSMina Almasry kref_put(&resv->refs, resv_map_release); 4369a1e78772SMel Gorman } 4370a1e78772SMel Gorman 437131383c68SDan Williams static int hugetlb_vm_op_split(struct vm_area_struct *vma, unsigned long addr) 437231383c68SDan Williams { 437331383c68SDan Williams if (addr & ~(huge_page_mask(hstate_vma(vma)))) 437431383c68SDan Williams return -EINVAL; 437531383c68SDan Williams return 0; 437631383c68SDan Williams } 437731383c68SDan Williams 437805ea8860SDan Williams static unsigned long hugetlb_vm_op_pagesize(struct vm_area_struct *vma) 437905ea8860SDan Williams { 4380aca78307SMiaohe Lin return huge_page_size(hstate_vma(vma)); 438105ea8860SDan Williams } 438205ea8860SDan Williams 43831da177e4SLinus Torvalds /* 43841da177e4SLinus Torvalds * We cannot handle pagefaults against hugetlb pages at all. They cause 43851da177e4SLinus Torvalds * handle_mm_fault() to try to instantiate regular-sized pages in the 43866c26d310SMiaohe Lin * hugepage VMA. do_page_fault() is supposed to trap this, so BUG is we get 43871da177e4SLinus Torvalds * this far. 43881da177e4SLinus Torvalds */ 4389b3ec9f33SSouptick Joarder static vm_fault_t hugetlb_vm_op_fault(struct vm_fault *vmf) 43901da177e4SLinus Torvalds { 43911da177e4SLinus Torvalds BUG(); 4392d0217ac0SNick Piggin return 0; 43931da177e4SLinus Torvalds } 43941da177e4SLinus Torvalds 4395eec3636aSJane Chu /* 4396eec3636aSJane Chu * When a new function is introduced to vm_operations_struct and added 4397eec3636aSJane Chu * to hugetlb_vm_ops, please consider adding the function to shm_vm_ops. 4398eec3636aSJane Chu * This is because under System V memory model, mappings created via 4399eec3636aSJane Chu * shmget/shmat with "huge page" specified are backed by hugetlbfs files, 4400eec3636aSJane Chu * their original vm_ops are overwritten with shm_vm_ops. 4401eec3636aSJane Chu */ 4402f0f37e2fSAlexey Dobriyan const struct vm_operations_struct hugetlb_vm_ops = { 4403d0217ac0SNick Piggin .fault = hugetlb_vm_op_fault, 440484afd99bSAndy Whitcroft .open = hugetlb_vm_op_open, 4405a1e78772SMel Gorman .close = hugetlb_vm_op_close, 4406dd3b614fSDmitry Safonov .may_split = hugetlb_vm_op_split, 440705ea8860SDan Williams .pagesize = hugetlb_vm_op_pagesize, 44081da177e4SLinus Torvalds }; 44091da177e4SLinus Torvalds 44101e8f889bSDavid Gibson static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, 44111e8f889bSDavid Gibson int writable) 441263551ae0SDavid Gibson { 441363551ae0SDavid Gibson pte_t entry; 441479c1c594SChristophe Leroy unsigned int shift = huge_page_shift(hstate_vma(vma)); 441563551ae0SDavid Gibson 44161e8f889bSDavid Gibson if (writable) { 4417106c992aSGerald Schaefer entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page, 4418106c992aSGerald Schaefer vma->vm_page_prot))); 441963551ae0SDavid Gibson } else { 4420106c992aSGerald Schaefer entry = huge_pte_wrprotect(mk_huge_pte(page, 4421106c992aSGerald Schaefer vma->vm_page_prot)); 442263551ae0SDavid Gibson } 442363551ae0SDavid Gibson entry = pte_mkyoung(entry); 442463551ae0SDavid Gibson entry = pte_mkhuge(entry); 442579c1c594SChristophe Leroy entry = arch_make_huge_pte(entry, shift, vma->vm_flags); 442663551ae0SDavid Gibson 442763551ae0SDavid Gibson return entry; 442863551ae0SDavid Gibson } 442963551ae0SDavid Gibson 44301e8f889bSDavid Gibson static void set_huge_ptep_writable(struct vm_area_struct *vma, 44311e8f889bSDavid Gibson unsigned long address, pte_t *ptep) 44321e8f889bSDavid Gibson { 44331e8f889bSDavid Gibson pte_t entry; 44341e8f889bSDavid Gibson 4435106c992aSGerald Schaefer entry = huge_pte_mkwrite(huge_pte_mkdirty(huge_ptep_get(ptep))); 443632f84528SChris Forbes if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) 44374b3073e1SRussell King update_mmu_cache(vma, address, ptep); 44381e8f889bSDavid Gibson } 44391e8f889bSDavid Gibson 4440d5ed7444SAneesh Kumar K.V bool is_hugetlb_entry_migration(pte_t pte) 44414a705fefSNaoya Horiguchi { 44424a705fefSNaoya Horiguchi swp_entry_t swp; 44434a705fefSNaoya Horiguchi 44444a705fefSNaoya Horiguchi if (huge_pte_none(pte) || pte_present(pte)) 4445d5ed7444SAneesh Kumar K.V return false; 44464a705fefSNaoya Horiguchi swp = pte_to_swp_entry(pte); 4447d79d176aSBaoquan He if (is_migration_entry(swp)) 4448d5ed7444SAneesh Kumar K.V return true; 44494a705fefSNaoya Horiguchi else 4450d5ed7444SAneesh Kumar K.V return false; 44514a705fefSNaoya Horiguchi } 44524a705fefSNaoya Horiguchi 44533e5c3600SBaoquan He static bool is_hugetlb_entry_hwpoisoned(pte_t pte) 44544a705fefSNaoya Horiguchi { 44554a705fefSNaoya Horiguchi swp_entry_t swp; 44564a705fefSNaoya Horiguchi 44574a705fefSNaoya Horiguchi if (huge_pte_none(pte) || pte_present(pte)) 44583e5c3600SBaoquan He return false; 44594a705fefSNaoya Horiguchi swp = pte_to_swp_entry(pte); 4460d79d176aSBaoquan He if (is_hwpoison_entry(swp)) 44613e5c3600SBaoquan He return true; 44624a705fefSNaoya Horiguchi else 44633e5c3600SBaoquan He return false; 44644a705fefSNaoya Horiguchi } 44651e8f889bSDavid Gibson 44664eae4efaSPeter Xu static void 44674eae4efaSPeter Xu hugetlb_install_page(struct vm_area_struct *vma, pte_t *ptep, unsigned long addr, 44684eae4efaSPeter Xu struct page *new_page) 44694eae4efaSPeter Xu { 44704eae4efaSPeter Xu __SetPageUptodate(new_page); 44714eae4efaSPeter Xu set_huge_pte_at(vma->vm_mm, addr, ptep, make_huge_pte(vma, new_page, 1)); 44724eae4efaSPeter Xu hugepage_add_new_anon_rmap(new_page, vma, addr); 44734eae4efaSPeter Xu hugetlb_count_add(pages_per_huge_page(hstate_vma(vma)), vma->vm_mm); 44744eae4efaSPeter Xu ClearHPageRestoreReserve(new_page); 44754eae4efaSPeter Xu SetHPageMigratable(new_page); 44764eae4efaSPeter Xu } 44774eae4efaSPeter Xu 447863551ae0SDavid Gibson int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, 447963551ae0SDavid Gibson struct vm_area_struct *vma) 448063551ae0SDavid Gibson { 44815e41540cSMike Kravetz pte_t *src_pte, *dst_pte, entry, dst_entry; 448263551ae0SDavid Gibson struct page *ptepage; 44831c59827dSHugh Dickins unsigned long addr; 4484ca6eb14dSPeter Xu bool cow = is_cow_mapping(vma->vm_flags); 4485a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 4486a5516438SAndi Kleen unsigned long sz = huge_page_size(h); 44874eae4efaSPeter Xu unsigned long npages = pages_per_huge_page(h); 4488c0d0381aSMike Kravetz struct address_space *mapping = vma->vm_file->f_mapping; 4489ac46d4f3SJérôme Glisse struct mmu_notifier_range range; 4490e8569dd2SAndreas Sandberg int ret = 0; 44911e8f889bSDavid Gibson 4492ac46d4f3SJérôme Glisse if (cow) { 44937269f999SJérôme Glisse mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, src, 44946f4f13e8SJérôme Glisse vma->vm_start, 4495ac46d4f3SJérôme Glisse vma->vm_end); 4496ac46d4f3SJérôme Glisse mmu_notifier_invalidate_range_start(&range); 4497c0d0381aSMike Kravetz } else { 4498c0d0381aSMike Kravetz /* 4499c0d0381aSMike Kravetz * For shared mappings i_mmap_rwsem must be held to call 4500c0d0381aSMike Kravetz * huge_pte_alloc, otherwise the returned ptep could go 4501c0d0381aSMike Kravetz * away if part of a shared pmd and another thread calls 4502c0d0381aSMike Kravetz * huge_pmd_unshare. 4503c0d0381aSMike Kravetz */ 4504c0d0381aSMike Kravetz i_mmap_lock_read(mapping); 4505ac46d4f3SJérôme Glisse } 4506e8569dd2SAndreas Sandberg 4507a5516438SAndi Kleen for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) { 4508cb900f41SKirill A. Shutemov spinlock_t *src_ptl, *dst_ptl; 45097868a208SPunit Agrawal src_pte = huge_pte_offset(src, addr, sz); 4510c74df32cSHugh Dickins if (!src_pte) 4511c74df32cSHugh Dickins continue; 4512aec44e0fSPeter Xu dst_pte = huge_pte_alloc(dst, vma, addr, sz); 4513e8569dd2SAndreas Sandberg if (!dst_pte) { 4514e8569dd2SAndreas Sandberg ret = -ENOMEM; 4515e8569dd2SAndreas Sandberg break; 4516e8569dd2SAndreas Sandberg } 4517c5c99429SLarry Woodman 45185e41540cSMike Kravetz /* 45195e41540cSMike Kravetz * If the pagetables are shared don't copy or take references. 45205e41540cSMike Kravetz * dst_pte == src_pte is the common case of src/dest sharing. 45215e41540cSMike Kravetz * 45225e41540cSMike Kravetz * However, src could have 'unshared' and dst shares with 45235e41540cSMike Kravetz * another vma. If dst_pte !none, this implies sharing. 45245e41540cSMike Kravetz * Check here before taking page table lock, and once again 45255e41540cSMike Kravetz * after taking the lock below. 45265e41540cSMike Kravetz */ 45275e41540cSMike Kravetz dst_entry = huge_ptep_get(dst_pte); 45285e41540cSMike Kravetz if ((dst_pte == src_pte) || !huge_pte_none(dst_entry)) 4529c5c99429SLarry Woodman continue; 4530c5c99429SLarry Woodman 4531cb900f41SKirill A. Shutemov dst_ptl = huge_pte_lock(h, dst, dst_pte); 4532cb900f41SKirill A. Shutemov src_ptl = huge_pte_lockptr(h, src, src_pte); 4533cb900f41SKirill A. Shutemov spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); 45344a705fefSNaoya Horiguchi entry = huge_ptep_get(src_pte); 45355e41540cSMike Kravetz dst_entry = huge_ptep_get(dst_pte); 45364eae4efaSPeter Xu again: 45375e41540cSMike Kravetz if (huge_pte_none(entry) || !huge_pte_none(dst_entry)) { 45385e41540cSMike Kravetz /* 45395e41540cSMike Kravetz * Skip if src entry none. Also, skip in the 45405e41540cSMike Kravetz * unlikely case dst entry !none as this implies 45415e41540cSMike Kravetz * sharing with another vma. 45425e41540cSMike Kravetz */ 45434a705fefSNaoya Horiguchi ; 45444a705fefSNaoya Horiguchi } else if (unlikely(is_hugetlb_entry_migration(entry) || 45454a705fefSNaoya Horiguchi is_hugetlb_entry_hwpoisoned(entry))) { 45464a705fefSNaoya Horiguchi swp_entry_t swp_entry = pte_to_swp_entry(entry); 45474a705fefSNaoya Horiguchi 45484dd845b5SAlistair Popple if (is_writable_migration_entry(swp_entry) && cow) { 45494a705fefSNaoya Horiguchi /* 45504a705fefSNaoya Horiguchi * COW mappings require pages in both 45514a705fefSNaoya Horiguchi * parent and child to be set to read. 45524a705fefSNaoya Horiguchi */ 45534dd845b5SAlistair Popple swp_entry = make_readable_migration_entry( 45544dd845b5SAlistair Popple swp_offset(swp_entry)); 45554a705fefSNaoya Horiguchi entry = swp_entry_to_pte(swp_entry); 4556e5251fd4SPunit Agrawal set_huge_swap_pte_at(src, addr, src_pte, 4557e5251fd4SPunit Agrawal entry, sz); 45584a705fefSNaoya Horiguchi } 4559e5251fd4SPunit Agrawal set_huge_swap_pte_at(dst, addr, dst_pte, entry, sz); 45604a705fefSNaoya Horiguchi } else { 45614eae4efaSPeter Xu entry = huge_ptep_get(src_pte); 45624eae4efaSPeter Xu ptepage = pte_page(entry); 45634eae4efaSPeter Xu get_page(ptepage); 45644eae4efaSPeter Xu 45654eae4efaSPeter Xu /* 45664eae4efaSPeter Xu * This is a rare case where we see pinned hugetlb 45674eae4efaSPeter Xu * pages while they're prone to COW. We need to do the 45684eae4efaSPeter Xu * COW earlier during fork. 45694eae4efaSPeter Xu * 45704eae4efaSPeter Xu * When pre-allocating the page or copying data, we 45714eae4efaSPeter Xu * need to be without the pgtable locks since we could 45724eae4efaSPeter Xu * sleep during the process. 45734eae4efaSPeter Xu */ 45744eae4efaSPeter Xu if (unlikely(page_needs_cow_for_dma(vma, ptepage))) { 45754eae4efaSPeter Xu pte_t src_pte_old = entry; 45764eae4efaSPeter Xu struct page *new; 45774eae4efaSPeter Xu 45784eae4efaSPeter Xu spin_unlock(src_ptl); 45794eae4efaSPeter Xu spin_unlock(dst_ptl); 45804eae4efaSPeter Xu /* Do not use reserve as it's private owned */ 45814eae4efaSPeter Xu new = alloc_huge_page(vma, addr, 1); 45824eae4efaSPeter Xu if (IS_ERR(new)) { 45834eae4efaSPeter Xu put_page(ptepage); 45844eae4efaSPeter Xu ret = PTR_ERR(new); 45854eae4efaSPeter Xu break; 45864eae4efaSPeter Xu } 45874eae4efaSPeter Xu copy_user_huge_page(new, ptepage, addr, vma, 45884eae4efaSPeter Xu npages); 45894eae4efaSPeter Xu put_page(ptepage); 45904eae4efaSPeter Xu 45914eae4efaSPeter Xu /* Install the new huge page if src pte stable */ 45924eae4efaSPeter Xu dst_ptl = huge_pte_lock(h, dst, dst_pte); 45934eae4efaSPeter Xu src_ptl = huge_pte_lockptr(h, src, src_pte); 45944eae4efaSPeter Xu spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); 45954eae4efaSPeter Xu entry = huge_ptep_get(src_pte); 45964eae4efaSPeter Xu if (!pte_same(src_pte_old, entry)) { 4597846be085SMike Kravetz restore_reserve_on_error(h, vma, addr, 4598846be085SMike Kravetz new); 45994eae4efaSPeter Xu put_page(new); 46004eae4efaSPeter Xu /* dst_entry won't change as in child */ 46014eae4efaSPeter Xu goto again; 46024eae4efaSPeter Xu } 46034eae4efaSPeter Xu hugetlb_install_page(vma, dst_pte, addr, new); 46044eae4efaSPeter Xu spin_unlock(src_ptl); 46054eae4efaSPeter Xu spin_unlock(dst_ptl); 46064eae4efaSPeter Xu continue; 46074eae4efaSPeter Xu } 46084eae4efaSPeter Xu 460934ee645eSJoerg Roedel if (cow) { 46100f10851eSJérôme Glisse /* 46110f10851eSJérôme Glisse * No need to notify as we are downgrading page 46120f10851eSJérôme Glisse * table protection not changing it to point 46130f10851eSJérôme Glisse * to a new page. 46140f10851eSJérôme Glisse * 4615ad56b738SMike Rapoport * See Documentation/vm/mmu_notifier.rst 46160f10851eSJérôme Glisse */ 46177f2e9525SGerald Schaefer huge_ptep_set_wrprotect(src, addr, src_pte); 461884894e1cSPeter Xu entry = huge_pte_wrprotect(entry); 461934ee645eSJoerg Roedel } 46204eae4efaSPeter Xu 462153f9263bSKirill A. Shutemov page_dup_rmap(ptepage, true); 462263551ae0SDavid Gibson set_huge_pte_at(dst, addr, dst_pte, entry); 46234eae4efaSPeter Xu hugetlb_count_add(npages, dst); 46241c59827dSHugh Dickins } 4625cb900f41SKirill A. Shutemov spin_unlock(src_ptl); 4626cb900f41SKirill A. Shutemov spin_unlock(dst_ptl); 462763551ae0SDavid Gibson } 462863551ae0SDavid Gibson 4629e8569dd2SAndreas Sandberg if (cow) 4630ac46d4f3SJérôme Glisse mmu_notifier_invalidate_range_end(&range); 4631c0d0381aSMike Kravetz else 4632c0d0381aSMike Kravetz i_mmap_unlock_read(mapping); 4633e8569dd2SAndreas Sandberg 4634e8569dd2SAndreas Sandberg return ret; 463563551ae0SDavid Gibson } 463663551ae0SDavid Gibson 463773c54763SPeter Xu static void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 463824669e58SAneesh Kumar K.V unsigned long start, unsigned long end, 463924669e58SAneesh Kumar K.V struct page *ref_page) 464063551ae0SDavid Gibson { 464163551ae0SDavid Gibson struct mm_struct *mm = vma->vm_mm; 464263551ae0SDavid Gibson unsigned long address; 4643c7546f8fSDavid Gibson pte_t *ptep; 464463551ae0SDavid Gibson pte_t pte; 4645cb900f41SKirill A. Shutemov spinlock_t *ptl; 464663551ae0SDavid Gibson struct page *page; 4647a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 4648a5516438SAndi Kleen unsigned long sz = huge_page_size(h); 4649ac46d4f3SJérôme Glisse struct mmu_notifier_range range; 4650a5516438SAndi Kleen 465163551ae0SDavid Gibson WARN_ON(!is_vm_hugetlb_page(vma)); 4652a5516438SAndi Kleen BUG_ON(start & ~huge_page_mask(h)); 4653a5516438SAndi Kleen BUG_ON(end & ~huge_page_mask(h)); 465463551ae0SDavid Gibson 465507e32661SAneesh Kumar K.V /* 465607e32661SAneesh Kumar K.V * This is a hugetlb vma, all the pte entries should point 465707e32661SAneesh Kumar K.V * to huge page. 465807e32661SAneesh Kumar K.V */ 4659ed6a7935SPeter Zijlstra tlb_change_page_size(tlb, sz); 466024669e58SAneesh Kumar K.V tlb_start_vma(tlb, vma); 4661dff11abeSMike Kravetz 4662dff11abeSMike Kravetz /* 4663dff11abeSMike Kravetz * If sharing possible, alert mmu notifiers of worst case. 4664dff11abeSMike Kravetz */ 46656f4f13e8SJérôme Glisse mmu_notifier_range_init(&range, MMU_NOTIFY_UNMAP, 0, vma, mm, start, 46666f4f13e8SJérôme Glisse end); 4667ac46d4f3SJérôme Glisse adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); 4668ac46d4f3SJérôme Glisse mmu_notifier_invalidate_range_start(&range); 4669569f48b8SHillf Danton address = start; 4670569f48b8SHillf Danton for (; address < end; address += sz) { 46717868a208SPunit Agrawal ptep = huge_pte_offset(mm, address, sz); 4672c7546f8fSDavid Gibson if (!ptep) 4673c7546f8fSDavid Gibson continue; 4674c7546f8fSDavid Gibson 4675cb900f41SKirill A. Shutemov ptl = huge_pte_lock(h, mm, ptep); 467634ae204fSMike Kravetz if (huge_pmd_unshare(mm, vma, &address, ptep)) { 467731d49da5SAneesh Kumar K.V spin_unlock(ptl); 4678dff11abeSMike Kravetz /* 4679dff11abeSMike Kravetz * We just unmapped a page of PMDs by clearing a PUD. 4680dff11abeSMike Kravetz * The caller's TLB flush range should cover this area. 4681dff11abeSMike Kravetz */ 468231d49da5SAneesh Kumar K.V continue; 468331d49da5SAneesh Kumar K.V } 468439dde65cSChen, Kenneth W 46856629326bSHillf Danton pte = huge_ptep_get(ptep); 468631d49da5SAneesh Kumar K.V if (huge_pte_none(pte)) { 468731d49da5SAneesh Kumar K.V spin_unlock(ptl); 468831d49da5SAneesh Kumar K.V continue; 468931d49da5SAneesh Kumar K.V } 46906629326bSHillf Danton 46916629326bSHillf Danton /* 46929fbc1f63SNaoya Horiguchi * Migrating hugepage or HWPoisoned hugepage is already 46939fbc1f63SNaoya Horiguchi * unmapped and its refcount is dropped, so just clear pte here. 46946629326bSHillf Danton */ 46959fbc1f63SNaoya Horiguchi if (unlikely(!pte_present(pte))) { 46969386fac3SPunit Agrawal huge_pte_clear(mm, address, ptep, sz); 469731d49da5SAneesh Kumar K.V spin_unlock(ptl); 469831d49da5SAneesh Kumar K.V continue; 46998c4894c6SNaoya Horiguchi } 47006629326bSHillf Danton 47016629326bSHillf Danton page = pte_page(pte); 470204f2cbe3SMel Gorman /* 470304f2cbe3SMel Gorman * If a reference page is supplied, it is because a specific 470404f2cbe3SMel Gorman * page is being unmapped, not a range. Ensure the page we 470504f2cbe3SMel Gorman * are about to unmap is the actual page of interest. 470604f2cbe3SMel Gorman */ 470704f2cbe3SMel Gorman if (ref_page) { 470831d49da5SAneesh Kumar K.V if (page != ref_page) { 470931d49da5SAneesh Kumar K.V spin_unlock(ptl); 471031d49da5SAneesh Kumar K.V continue; 471131d49da5SAneesh Kumar K.V } 471204f2cbe3SMel Gorman /* 471304f2cbe3SMel Gorman * Mark the VMA as having unmapped its page so that 471404f2cbe3SMel Gorman * future faults in this VMA will fail rather than 471504f2cbe3SMel Gorman * looking like data was lost 471604f2cbe3SMel Gorman */ 471704f2cbe3SMel Gorman set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED); 471804f2cbe3SMel Gorman } 471904f2cbe3SMel Gorman 4720c7546f8fSDavid Gibson pte = huge_ptep_get_and_clear(mm, address, ptep); 4721b528e4b6SAneesh Kumar K.V tlb_remove_huge_tlb_entry(h, tlb, ptep, address); 4722106c992aSGerald Schaefer if (huge_pte_dirty(pte)) 47236649a386SKen Chen set_page_dirty(page); 47249e81130bSHillf Danton 47255d317b2bSNaoya Horiguchi hugetlb_count_sub(pages_per_huge_page(h), mm); 4726d281ee61SKirill A. Shutemov page_remove_rmap(page, true); 472731d49da5SAneesh Kumar K.V 4728cb900f41SKirill A. Shutemov spin_unlock(ptl); 4729e77b0852SAneesh Kumar K.V tlb_remove_page_size(tlb, page, huge_page_size(h)); 473024669e58SAneesh Kumar K.V /* 473131d49da5SAneesh Kumar K.V * Bail out after unmapping reference page if supplied 473224669e58SAneesh Kumar K.V */ 473331d49da5SAneesh Kumar K.V if (ref_page) 473431d49da5SAneesh Kumar K.V break; 4735fe1668aeSChen, Kenneth W } 4736ac46d4f3SJérôme Glisse mmu_notifier_invalidate_range_end(&range); 473724669e58SAneesh Kumar K.V tlb_end_vma(tlb, vma); 47381da177e4SLinus Torvalds } 473963551ae0SDavid Gibson 4740d833352aSMel Gorman void __unmap_hugepage_range_final(struct mmu_gather *tlb, 4741d833352aSMel Gorman struct vm_area_struct *vma, unsigned long start, 4742d833352aSMel Gorman unsigned long end, struct page *ref_page) 4743d833352aSMel Gorman { 4744d833352aSMel Gorman __unmap_hugepage_range(tlb, vma, start, end, ref_page); 4745d833352aSMel Gorman 4746d833352aSMel Gorman /* 4747d833352aSMel Gorman * Clear this flag so that x86's huge_pmd_share page_table_shareable 4748d833352aSMel Gorman * test will fail on a vma being torn down, and not grab a page table 4749d833352aSMel Gorman * on its way out. We're lucky that the flag has such an appropriate 4750d833352aSMel Gorman * name, and can in fact be safely cleared here. We could clear it 4751d833352aSMel Gorman * before the __unmap_hugepage_range above, but all that's necessary 4752c8c06efaSDavidlohr Bueso * is to clear it before releasing the i_mmap_rwsem. This works 4753d833352aSMel Gorman * because in the context this is called, the VMA is about to be 4754c8c06efaSDavidlohr Bueso * destroyed and the i_mmap_rwsem is held. 4755d833352aSMel Gorman */ 4756d833352aSMel Gorman vma->vm_flags &= ~VM_MAYSHARE; 4757d833352aSMel Gorman } 4758d833352aSMel Gorman 4759502717f4SChen, Kenneth W void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, 476004f2cbe3SMel Gorman unsigned long end, struct page *ref_page) 4761502717f4SChen, Kenneth W { 476224669e58SAneesh Kumar K.V struct mmu_gather tlb; 4763dff11abeSMike Kravetz 4764a72afd87SWill Deacon tlb_gather_mmu(&tlb, vma->vm_mm); 476524669e58SAneesh Kumar K.V __unmap_hugepage_range(&tlb, vma, start, end, ref_page); 4766ae8eba8bSWill Deacon tlb_finish_mmu(&tlb); 4767502717f4SChen, Kenneth W } 4768502717f4SChen, Kenneth W 476904f2cbe3SMel Gorman /* 477004f2cbe3SMel Gorman * This is called when the original mapper is failing to COW a MAP_PRIVATE 4771578b7725SZhiyuan Dai * mapping it owns the reserve page for. The intention is to unmap the page 477204f2cbe3SMel Gorman * from other VMAs and let the children be SIGKILLed if they are faulting the 477304f2cbe3SMel Gorman * same region. 477404f2cbe3SMel Gorman */ 47752f4612afSDavidlohr Bueso static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, 47762a4b3dedSHarvey Harrison struct page *page, unsigned long address) 477704f2cbe3SMel Gorman { 47787526674dSAdam Litke struct hstate *h = hstate_vma(vma); 477904f2cbe3SMel Gorman struct vm_area_struct *iter_vma; 478004f2cbe3SMel Gorman struct address_space *mapping; 478104f2cbe3SMel Gorman pgoff_t pgoff; 478204f2cbe3SMel Gorman 478304f2cbe3SMel Gorman /* 478404f2cbe3SMel Gorman * vm_pgoff is in PAGE_SIZE units, hence the different calculation 478504f2cbe3SMel Gorman * from page cache lookup which is in HPAGE_SIZE units. 478604f2cbe3SMel Gorman */ 47877526674dSAdam Litke address = address & huge_page_mask(h); 478836e4f20aSMichal Hocko pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + 478936e4f20aSMichal Hocko vma->vm_pgoff; 479093c76a3dSAl Viro mapping = vma->vm_file->f_mapping; 479104f2cbe3SMel Gorman 47924eb2b1dcSMel Gorman /* 47934eb2b1dcSMel Gorman * Take the mapping lock for the duration of the table walk. As 47944eb2b1dcSMel Gorman * this mapping should be shared between all the VMAs, 47954eb2b1dcSMel Gorman * __unmap_hugepage_range() is called as the lock is already held 47964eb2b1dcSMel Gorman */ 479783cde9e8SDavidlohr Bueso i_mmap_lock_write(mapping); 47986b2dbba8SMichel Lespinasse vma_interval_tree_foreach(iter_vma, &mapping->i_mmap, pgoff, pgoff) { 479904f2cbe3SMel Gorman /* Do not unmap the current VMA */ 480004f2cbe3SMel Gorman if (iter_vma == vma) 480104f2cbe3SMel Gorman continue; 480204f2cbe3SMel Gorman 480304f2cbe3SMel Gorman /* 48042f84a899SMel Gorman * Shared VMAs have their own reserves and do not affect 48052f84a899SMel Gorman * MAP_PRIVATE accounting but it is possible that a shared 48062f84a899SMel Gorman * VMA is using the same page so check and skip such VMAs. 48072f84a899SMel Gorman */ 48082f84a899SMel Gorman if (iter_vma->vm_flags & VM_MAYSHARE) 48092f84a899SMel Gorman continue; 48102f84a899SMel Gorman 48112f84a899SMel Gorman /* 481204f2cbe3SMel Gorman * Unmap the page from other VMAs without their own reserves. 481304f2cbe3SMel Gorman * They get marked to be SIGKILLed if they fault in these 481404f2cbe3SMel Gorman * areas. This is because a future no-page fault on this VMA 481504f2cbe3SMel Gorman * could insert a zeroed page instead of the data existing 481604f2cbe3SMel Gorman * from the time of fork. This would look like data corruption 481704f2cbe3SMel Gorman */ 481804f2cbe3SMel Gorman if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER)) 481924669e58SAneesh Kumar K.V unmap_hugepage_range(iter_vma, address, 482024669e58SAneesh Kumar K.V address + huge_page_size(h), page); 482104f2cbe3SMel Gorman } 482283cde9e8SDavidlohr Bueso i_mmap_unlock_write(mapping); 482304f2cbe3SMel Gorman } 482404f2cbe3SMel Gorman 48250fe6e20bSNaoya Horiguchi /* 48260fe6e20bSNaoya Horiguchi * Hugetlb_cow() should be called with page lock of the original hugepage held. 4827ef009b25SMichal Hocko * Called with hugetlb_instantiation_mutex held and pte_page locked so we 4828ef009b25SMichal Hocko * cannot race with other handlers or page migration. 4829ef009b25SMichal Hocko * Keep the pte_same checks anyway to make transition from the mutex easier. 48300fe6e20bSNaoya Horiguchi */ 48312b740303SSouptick Joarder static vm_fault_t hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, 4832974e6d66SHuang Ying unsigned long address, pte_t *ptep, 4833cb900f41SKirill A. Shutemov struct page *pagecache_page, spinlock_t *ptl) 48341e8f889bSDavid Gibson { 48353999f52eSAneesh Kumar K.V pte_t pte; 4836a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 48371e8f889bSDavid Gibson struct page *old_page, *new_page; 48382b740303SSouptick Joarder int outside_reserve = 0; 48392b740303SSouptick Joarder vm_fault_t ret = 0; 4840974e6d66SHuang Ying unsigned long haddr = address & huge_page_mask(h); 4841ac46d4f3SJérôme Glisse struct mmu_notifier_range range; 48421e8f889bSDavid Gibson 48433999f52eSAneesh Kumar K.V pte = huge_ptep_get(ptep); 48441e8f889bSDavid Gibson old_page = pte_page(pte); 48451e8f889bSDavid Gibson 484604f2cbe3SMel Gorman retry_avoidcopy: 48471e8f889bSDavid Gibson /* If no-one else is actually using this page, avoid the copy 48481e8f889bSDavid Gibson * and just make the page writable */ 484937a2140dSJoonsoo Kim if (page_mapcount(old_page) == 1 && PageAnon(old_page)) { 48505a49973dSHugh Dickins page_move_anon_rmap(old_page, vma); 48515b7a1d40SHuang Ying set_huge_ptep_writable(vma, haddr, ptep); 485283c54070SNick Piggin return 0; 48531e8f889bSDavid Gibson } 48541e8f889bSDavid Gibson 485504f2cbe3SMel Gorman /* 485604f2cbe3SMel Gorman * If the process that created a MAP_PRIVATE mapping is about to 485704f2cbe3SMel Gorman * perform a COW due to a shared page count, attempt to satisfy 485804f2cbe3SMel Gorman * the allocation without using the existing reserves. The pagecache 485904f2cbe3SMel Gorman * page is used to determine if the reserve at this address was 486004f2cbe3SMel Gorman * consumed or not. If reserves were used, a partial faulted mapping 486104f2cbe3SMel Gorman * at the time of fork() could consume its reserves on COW instead 486204f2cbe3SMel Gorman * of the full address range. 486304f2cbe3SMel Gorman */ 48645944d011SJoonsoo Kim if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) && 486504f2cbe3SMel Gorman old_page != pagecache_page) 486604f2cbe3SMel Gorman outside_reserve = 1; 486704f2cbe3SMel Gorman 486809cbfeafSKirill A. Shutemov get_page(old_page); 4869b76c8cfbSLarry Woodman 4870ad4404a2SDavidlohr Bueso /* 4871ad4404a2SDavidlohr Bueso * Drop page table lock as buddy allocator may be called. It will 4872ad4404a2SDavidlohr Bueso * be acquired again before returning to the caller, as expected. 4873ad4404a2SDavidlohr Bueso */ 4874cb900f41SKirill A. Shutemov spin_unlock(ptl); 48755b7a1d40SHuang Ying new_page = alloc_huge_page(vma, haddr, outside_reserve); 48761e8f889bSDavid Gibson 48772fc39cecSAdam Litke if (IS_ERR(new_page)) { 487804f2cbe3SMel Gorman /* 487904f2cbe3SMel Gorman * If a process owning a MAP_PRIVATE mapping fails to COW, 488004f2cbe3SMel Gorman * it is due to references held by a child and an insufficient 488104f2cbe3SMel Gorman * huge page pool. To guarantee the original mappers 488204f2cbe3SMel Gorman * reliability, unmap the page from child processes. The child 488304f2cbe3SMel Gorman * may get SIGKILLed if it later faults. 488404f2cbe3SMel Gorman */ 488504f2cbe3SMel Gorman if (outside_reserve) { 4886e7dd91c4SMike Kravetz struct address_space *mapping = vma->vm_file->f_mapping; 4887e7dd91c4SMike Kravetz pgoff_t idx; 4888e7dd91c4SMike Kravetz u32 hash; 4889e7dd91c4SMike Kravetz 489009cbfeafSKirill A. Shutemov put_page(old_page); 489104f2cbe3SMel Gorman BUG_ON(huge_pte_none(pte)); 4892e7dd91c4SMike Kravetz /* 4893e7dd91c4SMike Kravetz * Drop hugetlb_fault_mutex and i_mmap_rwsem before 4894e7dd91c4SMike Kravetz * unmapping. unmapping needs to hold i_mmap_rwsem 4895e7dd91c4SMike Kravetz * in write mode. Dropping i_mmap_rwsem in read mode 4896e7dd91c4SMike Kravetz * here is OK as COW mappings do not interact with 4897e7dd91c4SMike Kravetz * PMD sharing. 4898e7dd91c4SMike Kravetz * 4899e7dd91c4SMike Kravetz * Reacquire both after unmap operation. 4900e7dd91c4SMike Kravetz */ 4901e7dd91c4SMike Kravetz idx = vma_hugecache_offset(h, vma, haddr); 4902e7dd91c4SMike Kravetz hash = hugetlb_fault_mutex_hash(mapping, idx); 4903e7dd91c4SMike Kravetz mutex_unlock(&hugetlb_fault_mutex_table[hash]); 4904e7dd91c4SMike Kravetz i_mmap_unlock_read(mapping); 4905e7dd91c4SMike Kravetz 49065b7a1d40SHuang Ying unmap_ref_private(mm, vma, old_page, haddr); 4907e7dd91c4SMike Kravetz 4908e7dd91c4SMike Kravetz i_mmap_lock_read(mapping); 4909e7dd91c4SMike Kravetz mutex_lock(&hugetlb_fault_mutex_table[hash]); 4910cb900f41SKirill A. Shutemov spin_lock(ptl); 49115b7a1d40SHuang Ying ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); 4912a9af0c5dSNaoya Horiguchi if (likely(ptep && 4913a9af0c5dSNaoya Horiguchi pte_same(huge_ptep_get(ptep), pte))) 491404f2cbe3SMel Gorman goto retry_avoidcopy; 4915a734bcc8SHillf Danton /* 4916cb900f41SKirill A. Shutemov * race occurs while re-acquiring page table 4917cb900f41SKirill A. Shutemov * lock, and our job is done. 4918a734bcc8SHillf Danton */ 4919a734bcc8SHillf Danton return 0; 492004f2cbe3SMel Gorman } 492104f2cbe3SMel Gorman 49222b740303SSouptick Joarder ret = vmf_error(PTR_ERR(new_page)); 4923ad4404a2SDavidlohr Bueso goto out_release_old; 49241e8f889bSDavid Gibson } 49251e8f889bSDavid Gibson 49260fe6e20bSNaoya Horiguchi /* 49270fe6e20bSNaoya Horiguchi * When the original hugepage is shared one, it does not have 49280fe6e20bSNaoya Horiguchi * anon_vma prepared. 49290fe6e20bSNaoya Horiguchi */ 493044e2aa93SDean Nelson if (unlikely(anon_vma_prepare(vma))) { 4931ad4404a2SDavidlohr Bueso ret = VM_FAULT_OOM; 4932ad4404a2SDavidlohr Bueso goto out_release_all; 493344e2aa93SDean Nelson } 49340fe6e20bSNaoya Horiguchi 4935974e6d66SHuang Ying copy_user_huge_page(new_page, old_page, address, vma, 493647ad8475SAndrea Arcangeli pages_per_huge_page(h)); 49370ed361deSNick Piggin __SetPageUptodate(new_page); 49381e8f889bSDavid Gibson 49397269f999SJérôme Glisse mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, mm, haddr, 49406f4f13e8SJérôme Glisse haddr + huge_page_size(h)); 4941ac46d4f3SJérôme Glisse mmu_notifier_invalidate_range_start(&range); 4942ad4404a2SDavidlohr Bueso 4943b76c8cfbSLarry Woodman /* 4944cb900f41SKirill A. Shutemov * Retake the page table lock to check for racing updates 4945b76c8cfbSLarry Woodman * before the page tables are altered 4946b76c8cfbSLarry Woodman */ 4947cb900f41SKirill A. Shutemov spin_lock(ptl); 49485b7a1d40SHuang Ying ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); 4949a9af0c5dSNaoya Horiguchi if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { 4950d6995da3SMike Kravetz ClearHPageRestoreReserve(new_page); 495107443a85SJoonsoo Kim 49521e8f889bSDavid Gibson /* Break COW */ 49535b7a1d40SHuang Ying huge_ptep_clear_flush(vma, haddr, ptep); 4954ac46d4f3SJérôme Glisse mmu_notifier_invalidate_range(mm, range.start, range.end); 49555b7a1d40SHuang Ying set_huge_pte_at(mm, haddr, ptep, 49561e8f889bSDavid Gibson make_huge_pte(vma, new_page, 1)); 4957d281ee61SKirill A. Shutemov page_remove_rmap(old_page, true); 49585b7a1d40SHuang Ying hugepage_add_new_anon_rmap(new_page, vma, haddr); 49598f251a3dSMike Kravetz SetHPageMigratable(new_page); 49601e8f889bSDavid Gibson /* Make the old page be freed below */ 49611e8f889bSDavid Gibson new_page = old_page; 49621e8f889bSDavid Gibson } 4963cb900f41SKirill A. Shutemov spin_unlock(ptl); 4964ac46d4f3SJérôme Glisse mmu_notifier_invalidate_range_end(&range); 4965ad4404a2SDavidlohr Bueso out_release_all: 4966c7b1850dSMike Kravetz /* No restore in case of successful pagetable update (Break COW) */ 4967c7b1850dSMike Kravetz if (new_page != old_page) 49685b7a1d40SHuang Ying restore_reserve_on_error(h, vma, haddr, new_page); 496909cbfeafSKirill A. Shutemov put_page(new_page); 4970ad4404a2SDavidlohr Bueso out_release_old: 497109cbfeafSKirill A. Shutemov put_page(old_page); 49728312034fSJoonsoo Kim 4973ad4404a2SDavidlohr Bueso spin_lock(ptl); /* Caller expects lock to be held */ 4974ad4404a2SDavidlohr Bueso return ret; 49751e8f889bSDavid Gibson } 49761e8f889bSDavid Gibson 497704f2cbe3SMel Gorman /* Return the pagecache page at a given address within a VMA */ 4978a5516438SAndi Kleen static struct page *hugetlbfs_pagecache_page(struct hstate *h, 4979a5516438SAndi Kleen struct vm_area_struct *vma, unsigned long address) 498004f2cbe3SMel Gorman { 498104f2cbe3SMel Gorman struct address_space *mapping; 4982e7c4b0bfSAndy Whitcroft pgoff_t idx; 498304f2cbe3SMel Gorman 498404f2cbe3SMel Gorman mapping = vma->vm_file->f_mapping; 4985a5516438SAndi Kleen idx = vma_hugecache_offset(h, vma, address); 498604f2cbe3SMel Gorman 498704f2cbe3SMel Gorman return find_lock_page(mapping, idx); 498804f2cbe3SMel Gorman } 498904f2cbe3SMel Gorman 49903ae77f43SHugh Dickins /* 49913ae77f43SHugh Dickins * Return whether there is a pagecache page to back given address within VMA. 49923ae77f43SHugh Dickins * Caller follow_hugetlb_page() holds page_table_lock so we cannot lock_page. 49933ae77f43SHugh Dickins */ 49943ae77f43SHugh Dickins static bool hugetlbfs_pagecache_present(struct hstate *h, 49952a15efc9SHugh Dickins struct vm_area_struct *vma, unsigned long address) 49962a15efc9SHugh Dickins { 49972a15efc9SHugh Dickins struct address_space *mapping; 49982a15efc9SHugh Dickins pgoff_t idx; 49992a15efc9SHugh Dickins struct page *page; 50002a15efc9SHugh Dickins 50012a15efc9SHugh Dickins mapping = vma->vm_file->f_mapping; 50022a15efc9SHugh Dickins idx = vma_hugecache_offset(h, vma, address); 50032a15efc9SHugh Dickins 50042a15efc9SHugh Dickins page = find_get_page(mapping, idx); 50052a15efc9SHugh Dickins if (page) 50062a15efc9SHugh Dickins put_page(page); 50072a15efc9SHugh Dickins return page != NULL; 50082a15efc9SHugh Dickins } 50092a15efc9SHugh Dickins 5010ab76ad54SMike Kravetz int huge_add_to_page_cache(struct page *page, struct address_space *mapping, 5011ab76ad54SMike Kravetz pgoff_t idx) 5012ab76ad54SMike Kravetz { 5013ab76ad54SMike Kravetz struct inode *inode = mapping->host; 5014ab76ad54SMike Kravetz struct hstate *h = hstate_inode(inode); 5015ab76ad54SMike Kravetz int err = add_to_page_cache(page, mapping, idx, GFP_KERNEL); 5016ab76ad54SMike Kravetz 5017ab76ad54SMike Kravetz if (err) 5018ab76ad54SMike Kravetz return err; 5019d6995da3SMike Kravetz ClearHPageRestoreReserve(page); 5020ab76ad54SMike Kravetz 502122146c3cSMike Kravetz /* 502222146c3cSMike Kravetz * set page dirty so that it will not be removed from cache/file 502322146c3cSMike Kravetz * by non-hugetlbfs specific code paths. 502422146c3cSMike Kravetz */ 502522146c3cSMike Kravetz set_page_dirty(page); 502622146c3cSMike Kravetz 5027ab76ad54SMike Kravetz spin_lock(&inode->i_lock); 5028ab76ad54SMike Kravetz inode->i_blocks += blocks_per_huge_page(h); 5029ab76ad54SMike Kravetz spin_unlock(&inode->i_lock); 5030ab76ad54SMike Kravetz return 0; 5031ab76ad54SMike Kravetz } 5032ab76ad54SMike Kravetz 50337677f7fdSAxel Rasmussen static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma, 50347677f7fdSAxel Rasmussen struct address_space *mapping, 50357677f7fdSAxel Rasmussen pgoff_t idx, 50367677f7fdSAxel Rasmussen unsigned int flags, 50377677f7fdSAxel Rasmussen unsigned long haddr, 50387677f7fdSAxel Rasmussen unsigned long reason) 50397677f7fdSAxel Rasmussen { 50407677f7fdSAxel Rasmussen vm_fault_t ret; 50417677f7fdSAxel Rasmussen u32 hash; 50427677f7fdSAxel Rasmussen struct vm_fault vmf = { 50437677f7fdSAxel Rasmussen .vma = vma, 50447677f7fdSAxel Rasmussen .address = haddr, 50457677f7fdSAxel Rasmussen .flags = flags, 50467677f7fdSAxel Rasmussen 50477677f7fdSAxel Rasmussen /* 50487677f7fdSAxel Rasmussen * Hard to debug if it ends up being 50497677f7fdSAxel Rasmussen * used by a callee that assumes 50507677f7fdSAxel Rasmussen * something about the other 50517677f7fdSAxel Rasmussen * uninitialized fields... same as in 50527677f7fdSAxel Rasmussen * memory.c 50537677f7fdSAxel Rasmussen */ 50547677f7fdSAxel Rasmussen }; 50557677f7fdSAxel Rasmussen 50567677f7fdSAxel Rasmussen /* 50577677f7fdSAxel Rasmussen * hugetlb_fault_mutex and i_mmap_rwsem must be 50587677f7fdSAxel Rasmussen * dropped before handling userfault. Reacquire 50597677f7fdSAxel Rasmussen * after handling fault to make calling code simpler. 50607677f7fdSAxel Rasmussen */ 50617677f7fdSAxel Rasmussen hash = hugetlb_fault_mutex_hash(mapping, idx); 50627677f7fdSAxel Rasmussen mutex_unlock(&hugetlb_fault_mutex_table[hash]); 50637677f7fdSAxel Rasmussen i_mmap_unlock_read(mapping); 50647677f7fdSAxel Rasmussen ret = handle_userfault(&vmf, reason); 50657677f7fdSAxel Rasmussen i_mmap_lock_read(mapping); 50667677f7fdSAxel Rasmussen mutex_lock(&hugetlb_fault_mutex_table[hash]); 50677677f7fdSAxel Rasmussen 50687677f7fdSAxel Rasmussen return ret; 50697677f7fdSAxel Rasmussen } 50707677f7fdSAxel Rasmussen 50712b740303SSouptick Joarder static vm_fault_t hugetlb_no_page(struct mm_struct *mm, 50722b740303SSouptick Joarder struct vm_area_struct *vma, 50738382d914SDavidlohr Bueso struct address_space *mapping, pgoff_t idx, 5074788c7df4SHugh Dickins unsigned long address, pte_t *ptep, unsigned int flags) 5075ac9b9c66SHugh Dickins { 5076a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 50772b740303SSouptick Joarder vm_fault_t ret = VM_FAULT_SIGBUS; 5078409eb8c2SHillf Danton int anon_rmap = 0; 50794c887265SAdam Litke unsigned long size; 50804c887265SAdam Litke struct page *page; 50811e8f889bSDavid Gibson pte_t new_pte; 5082cb900f41SKirill A. Shutemov spinlock_t *ptl; 5083285b8dcaSHuang Ying unsigned long haddr = address & huge_page_mask(h); 5084c7b1850dSMike Kravetz bool new_page, new_pagecache_page = false; 50854c887265SAdam Litke 508604f2cbe3SMel Gorman /* 508704f2cbe3SMel Gorman * Currently, we are forced to kill the process in the event the 508804f2cbe3SMel Gorman * original mapper has unmapped pages from the child due to a failed 508925985edcSLucas De Marchi * COW. Warn that such a situation has occurred as it may not be obvious 509004f2cbe3SMel Gorman */ 509104f2cbe3SMel Gorman if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) { 5092910154d5SGeoffrey Thomas pr_warn_ratelimited("PID %d killed due to inadequate hugepage pool\n", 509304f2cbe3SMel Gorman current->pid); 509404f2cbe3SMel Gorman return ret; 509504f2cbe3SMel Gorman } 509604f2cbe3SMel Gorman 50974c887265SAdam Litke /* 509887bf91d3SMike Kravetz * We can not race with truncation due to holding i_mmap_rwsem. 509987bf91d3SMike Kravetz * i_size is modified when holding i_mmap_rwsem, so check here 510087bf91d3SMike Kravetz * once for faults beyond end of file. 51014c887265SAdam Litke */ 5102a5516438SAndi Kleen size = i_size_read(mapping->host) >> huge_page_shift(h); 5103ebed4bfcSHugh Dickins if (idx >= size) 5104ebed4bfcSHugh Dickins goto out; 51051a1aad8aSMike Kravetz 510687bf91d3SMike Kravetz retry: 5107c7b1850dSMike Kravetz new_page = false; 510887bf91d3SMike Kravetz page = find_lock_page(mapping, idx); 510987bf91d3SMike Kravetz if (!page) { 51107677f7fdSAxel Rasmussen /* Check for page in userfault range */ 51111a1aad8aSMike Kravetz if (userfaultfd_missing(vma)) { 51127677f7fdSAxel Rasmussen ret = hugetlb_handle_userfault(vma, mapping, idx, 51137677f7fdSAxel Rasmussen flags, haddr, 51147677f7fdSAxel Rasmussen VM_UFFD_MISSING); 51151a1aad8aSMike Kravetz goto out; 51161a1aad8aSMike Kravetz } 51171a1aad8aSMike Kravetz 5118285b8dcaSHuang Ying page = alloc_huge_page(vma, haddr, 0); 51192fc39cecSAdam Litke if (IS_ERR(page)) { 51204643d67eSMike Kravetz /* 51214643d67eSMike Kravetz * Returning error will result in faulting task being 51224643d67eSMike Kravetz * sent SIGBUS. The hugetlb fault mutex prevents two 51234643d67eSMike Kravetz * tasks from racing to fault in the same page which 51244643d67eSMike Kravetz * could result in false unable to allocate errors. 51254643d67eSMike Kravetz * Page migration does not take the fault mutex, but 51264643d67eSMike Kravetz * does a clear then write of pte's under page table 51274643d67eSMike Kravetz * lock. Page fault code could race with migration, 51284643d67eSMike Kravetz * notice the clear pte and try to allocate a page 51294643d67eSMike Kravetz * here. Before returning error, get ptl and make 51304643d67eSMike Kravetz * sure there really is no pte entry. 51314643d67eSMike Kravetz */ 51324643d67eSMike Kravetz ptl = huge_pte_lock(h, mm, ptep); 51334643d67eSMike Kravetz ret = 0; 5134d83e6c8aSMiaohe Lin if (huge_pte_none(huge_ptep_get(ptep))) 51352b740303SSouptick Joarder ret = vmf_error(PTR_ERR(page)); 5136d83e6c8aSMiaohe Lin spin_unlock(ptl); 51376bda666aSChristoph Lameter goto out; 51386bda666aSChristoph Lameter } 513947ad8475SAndrea Arcangeli clear_huge_page(page, address, pages_per_huge_page(h)); 51400ed361deSNick Piggin __SetPageUptodate(page); 5141cb6acd01SMike Kravetz new_page = true; 5142ac9b9c66SHugh Dickins 5143f83a275dSMel Gorman if (vma->vm_flags & VM_MAYSHARE) { 5144ab76ad54SMike Kravetz int err = huge_add_to_page_cache(page, mapping, idx); 51456bda666aSChristoph Lameter if (err) { 51466bda666aSChristoph Lameter put_page(page); 51476bda666aSChristoph Lameter if (err == -EEXIST) 51486bda666aSChristoph Lameter goto retry; 51496bda666aSChristoph Lameter goto out; 51506bda666aSChristoph Lameter } 5151c7b1850dSMike Kravetz new_pagecache_page = true; 515223be7468SMel Gorman } else { 51536bda666aSChristoph Lameter lock_page(page); 51540fe6e20bSNaoya Horiguchi if (unlikely(anon_vma_prepare(vma))) { 51550fe6e20bSNaoya Horiguchi ret = VM_FAULT_OOM; 51560fe6e20bSNaoya Horiguchi goto backout_unlocked; 515723be7468SMel Gorman } 5158409eb8c2SHillf Danton anon_rmap = 1; 51590fe6e20bSNaoya Horiguchi } 51600fe6e20bSNaoya Horiguchi } else { 516157303d80SAndy Whitcroft /* 5162998b4382SNaoya Horiguchi * If memory error occurs between mmap() and fault, some process 5163998b4382SNaoya Horiguchi * don't have hwpoisoned swap entry for errored virtual address. 5164998b4382SNaoya Horiguchi * So we need to block hugepage fault by PG_hwpoison bit check. 5165fd6a03edSNaoya Horiguchi */ 5166fd6a03edSNaoya Horiguchi if (unlikely(PageHWPoison(page))) { 51670eb98f15SMiaohe Lin ret = VM_FAULT_HWPOISON_LARGE | 5168972dc4deSAneesh Kumar K.V VM_FAULT_SET_HINDEX(hstate_index(h)); 5169fd6a03edSNaoya Horiguchi goto backout_unlocked; 51706bda666aSChristoph Lameter } 51717677f7fdSAxel Rasmussen 51727677f7fdSAxel Rasmussen /* Check for page in userfault range. */ 51737677f7fdSAxel Rasmussen if (userfaultfd_minor(vma)) { 51747677f7fdSAxel Rasmussen unlock_page(page); 51757677f7fdSAxel Rasmussen put_page(page); 51767677f7fdSAxel Rasmussen ret = hugetlb_handle_userfault(vma, mapping, idx, 51777677f7fdSAxel Rasmussen flags, haddr, 51787677f7fdSAxel Rasmussen VM_UFFD_MINOR); 51797677f7fdSAxel Rasmussen goto out; 51807677f7fdSAxel Rasmussen } 5181998b4382SNaoya Horiguchi } 51821e8f889bSDavid Gibson 518357303d80SAndy Whitcroft /* 518457303d80SAndy Whitcroft * If we are going to COW a private mapping later, we examine the 518557303d80SAndy Whitcroft * pending reservations for this page now. This will ensure that 518657303d80SAndy Whitcroft * any allocations necessary to record that reservation occur outside 518757303d80SAndy Whitcroft * the spinlock. 518857303d80SAndy Whitcroft */ 51895e911373SMike Kravetz if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { 5190285b8dcaSHuang Ying if (vma_needs_reservation(h, vma, haddr) < 0) { 51912b26736cSAndy Whitcroft ret = VM_FAULT_OOM; 51922b26736cSAndy Whitcroft goto backout_unlocked; 51932b26736cSAndy Whitcroft } 51945e911373SMike Kravetz /* Just decrements count, does not deallocate */ 5195285b8dcaSHuang Ying vma_end_reservation(h, vma, haddr); 51965e911373SMike Kravetz } 519757303d80SAndy Whitcroft 51988bea8052SAneesh Kumar K.V ptl = huge_pte_lock(h, mm, ptep); 519983c54070SNick Piggin ret = 0; 52007f2e9525SGerald Schaefer if (!huge_pte_none(huge_ptep_get(ptep))) 52014c887265SAdam Litke goto backout; 52024c887265SAdam Litke 520307443a85SJoonsoo Kim if (anon_rmap) { 5204d6995da3SMike Kravetz ClearHPageRestoreReserve(page); 5205285b8dcaSHuang Ying hugepage_add_new_anon_rmap(page, vma, haddr); 5206ac714904SChoi Gi-yong } else 520753f9263bSKirill A. Shutemov page_dup_rmap(page, true); 52081e8f889bSDavid Gibson new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) 52091e8f889bSDavid Gibson && (vma->vm_flags & VM_SHARED))); 5210285b8dcaSHuang Ying set_huge_pte_at(mm, haddr, ptep, new_pte); 52111e8f889bSDavid Gibson 52125d317b2bSNaoya Horiguchi hugetlb_count_add(pages_per_huge_page(h), mm); 5213788c7df4SHugh Dickins if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { 52141e8f889bSDavid Gibson /* Optimization, do the COW without a second fault */ 5215974e6d66SHuang Ying ret = hugetlb_cow(mm, vma, address, ptep, page, ptl); 52161e8f889bSDavid Gibson } 52171e8f889bSDavid Gibson 5218cb900f41SKirill A. Shutemov spin_unlock(ptl); 5219cb6acd01SMike Kravetz 5220cb6acd01SMike Kravetz /* 52218f251a3dSMike Kravetz * Only set HPageMigratable in newly allocated pages. Existing pages 52228f251a3dSMike Kravetz * found in the pagecache may not have HPageMigratableset if they have 52238f251a3dSMike Kravetz * been isolated for migration. 5224cb6acd01SMike Kravetz */ 5225cb6acd01SMike Kravetz if (new_page) 52268f251a3dSMike Kravetz SetHPageMigratable(page); 5227cb6acd01SMike Kravetz 52284c887265SAdam Litke unlock_page(page); 52294c887265SAdam Litke out: 5230ac9b9c66SHugh Dickins return ret; 52314c887265SAdam Litke 52324c887265SAdam Litke backout: 5233cb900f41SKirill A. Shutemov spin_unlock(ptl); 52342b26736cSAndy Whitcroft backout_unlocked: 52354c887265SAdam Litke unlock_page(page); 5236c7b1850dSMike Kravetz /* restore reserve for newly allocated pages not in page cache */ 5237c7b1850dSMike Kravetz if (new_page && !new_pagecache_page) 5238285b8dcaSHuang Ying restore_reserve_on_error(h, vma, haddr, page); 52394c887265SAdam Litke put_page(page); 52404c887265SAdam Litke goto out; 5241ac9b9c66SHugh Dickins } 5242ac9b9c66SHugh Dickins 52438382d914SDavidlohr Bueso #ifdef CONFIG_SMP 5244188b04a7SWei Yang u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx) 52458382d914SDavidlohr Bueso { 52468382d914SDavidlohr Bueso unsigned long key[2]; 52478382d914SDavidlohr Bueso u32 hash; 52488382d914SDavidlohr Bueso 52498382d914SDavidlohr Bueso key[0] = (unsigned long) mapping; 52508382d914SDavidlohr Bueso key[1] = idx; 52518382d914SDavidlohr Bueso 525255254636SMike Kravetz hash = jhash2((u32 *)&key, sizeof(key)/(sizeof(u32)), 0); 52538382d914SDavidlohr Bueso 52548382d914SDavidlohr Bueso return hash & (num_fault_mutexes - 1); 52558382d914SDavidlohr Bueso } 52568382d914SDavidlohr Bueso #else 52578382d914SDavidlohr Bueso /* 52586c26d310SMiaohe Lin * For uniprocessor systems we always use a single mutex, so just 52598382d914SDavidlohr Bueso * return 0 and avoid the hashing overhead. 52608382d914SDavidlohr Bueso */ 5261188b04a7SWei Yang u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx) 52628382d914SDavidlohr Bueso { 52638382d914SDavidlohr Bueso return 0; 52648382d914SDavidlohr Bueso } 52658382d914SDavidlohr Bueso #endif 52668382d914SDavidlohr Bueso 52672b740303SSouptick Joarder vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, 5268788c7df4SHugh Dickins unsigned long address, unsigned int flags) 526986e5216fSAdam Litke { 52708382d914SDavidlohr Bueso pte_t *ptep, entry; 5271cb900f41SKirill A. Shutemov spinlock_t *ptl; 52722b740303SSouptick Joarder vm_fault_t ret; 52738382d914SDavidlohr Bueso u32 hash; 52748382d914SDavidlohr Bueso pgoff_t idx; 52750fe6e20bSNaoya Horiguchi struct page *page = NULL; 527657303d80SAndy Whitcroft struct page *pagecache_page = NULL; 5277a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 52788382d914SDavidlohr Bueso struct address_space *mapping; 52790f792cf9SNaoya Horiguchi int need_wait_lock = 0; 5280285b8dcaSHuang Ying unsigned long haddr = address & huge_page_mask(h); 528186e5216fSAdam Litke 5282285b8dcaSHuang Ying ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); 5283fd6a03edSNaoya Horiguchi if (ptep) { 5284c0d0381aSMike Kravetz /* 5285c0d0381aSMike Kravetz * Since we hold no locks, ptep could be stale. That is 5286c0d0381aSMike Kravetz * OK as we are only making decisions based on content and 5287c0d0381aSMike Kravetz * not actually modifying content here. 5288c0d0381aSMike Kravetz */ 5289fd6a03edSNaoya Horiguchi entry = huge_ptep_get(ptep); 5290290408d4SNaoya Horiguchi if (unlikely(is_hugetlb_entry_migration(entry))) { 5291cb900f41SKirill A. Shutemov migration_entry_wait_huge(vma, mm, ptep); 5292290408d4SNaoya Horiguchi return 0; 5293290408d4SNaoya Horiguchi } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) 5294aa50d3a7SAndi Kleen return VM_FAULT_HWPOISON_LARGE | 5295972dc4deSAneesh Kumar K.V VM_FAULT_SET_HINDEX(hstate_index(h)); 5296b43a9990SMike Kravetz } 52978382d914SDavidlohr Bueso 5298c0d0381aSMike Kravetz /* 5299c0d0381aSMike Kravetz * Acquire i_mmap_rwsem before calling huge_pte_alloc and hold 530087bf91d3SMike Kravetz * until finished with ptep. This serves two purposes: 530187bf91d3SMike Kravetz * 1) It prevents huge_pmd_unshare from being called elsewhere 530287bf91d3SMike Kravetz * and making the ptep no longer valid. 530387bf91d3SMike Kravetz * 2) It synchronizes us with i_size modifications during truncation. 5304c0d0381aSMike Kravetz * 5305c0d0381aSMike Kravetz * ptep could have already be assigned via huge_pte_offset. That 5306c0d0381aSMike Kravetz * is OK, as huge_pte_alloc will return the same value unless 5307c0d0381aSMike Kravetz * something has changed. 5308c0d0381aSMike Kravetz */ 5309ddeaab32SMike Kravetz mapping = vma->vm_file->f_mapping; 5310c0d0381aSMike Kravetz i_mmap_lock_read(mapping); 5311aec44e0fSPeter Xu ptep = huge_pte_alloc(mm, vma, haddr, huge_page_size(h)); 5312c0d0381aSMike Kravetz if (!ptep) { 5313c0d0381aSMike Kravetz i_mmap_unlock_read(mapping); 5314c0d0381aSMike Kravetz return VM_FAULT_OOM; 5315c0d0381aSMike Kravetz } 5316ddeaab32SMike Kravetz 53173935baa9SDavid Gibson /* 53183935baa9SDavid Gibson * Serialize hugepage allocation and instantiation, so that we don't 53193935baa9SDavid Gibson * get spurious allocation failures if two CPUs race to instantiate 53203935baa9SDavid Gibson * the same page in the page cache. 53213935baa9SDavid Gibson */ 5322c0d0381aSMike Kravetz idx = vma_hugecache_offset(h, vma, haddr); 5323188b04a7SWei Yang hash = hugetlb_fault_mutex_hash(mapping, idx); 5324c672c7f2SMike Kravetz mutex_lock(&hugetlb_fault_mutex_table[hash]); 53258382d914SDavidlohr Bueso 53267f2e9525SGerald Schaefer entry = huge_ptep_get(ptep); 53277f2e9525SGerald Schaefer if (huge_pte_none(entry)) { 53288382d914SDavidlohr Bueso ret = hugetlb_no_page(mm, vma, mapping, idx, address, ptep, flags); 5329b4d1d99fSDavid Gibson goto out_mutex; 53303935baa9SDavid Gibson } 533186e5216fSAdam Litke 533283c54070SNick Piggin ret = 0; 53331e8f889bSDavid Gibson 533457303d80SAndy Whitcroft /* 53350f792cf9SNaoya Horiguchi * entry could be a migration/hwpoison entry at this point, so this 53360f792cf9SNaoya Horiguchi * check prevents the kernel from going below assuming that we have 53377c8de358SEthon Paul * an active hugepage in pagecache. This goto expects the 2nd page 53387c8de358SEthon Paul * fault, and is_hugetlb_entry_(migration|hwpoisoned) check will 53397c8de358SEthon Paul * properly handle it. 53400f792cf9SNaoya Horiguchi */ 53410f792cf9SNaoya Horiguchi if (!pte_present(entry)) 53420f792cf9SNaoya Horiguchi goto out_mutex; 53430f792cf9SNaoya Horiguchi 53440f792cf9SNaoya Horiguchi /* 534557303d80SAndy Whitcroft * If we are going to COW the mapping later, we examine the pending 534657303d80SAndy Whitcroft * reservations for this page now. This will ensure that any 534757303d80SAndy Whitcroft * allocations necessary to record that reservation occur outside the 534857303d80SAndy Whitcroft * spinlock. For private mappings, we also lookup the pagecache 534957303d80SAndy Whitcroft * page now as it is used to determine if a reservation has been 535057303d80SAndy Whitcroft * consumed. 535157303d80SAndy Whitcroft */ 5352106c992aSGerald Schaefer if ((flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) { 5353285b8dcaSHuang Ying if (vma_needs_reservation(h, vma, haddr) < 0) { 53542b26736cSAndy Whitcroft ret = VM_FAULT_OOM; 5355b4d1d99fSDavid Gibson goto out_mutex; 53562b26736cSAndy Whitcroft } 53575e911373SMike Kravetz /* Just decrements count, does not deallocate */ 5358285b8dcaSHuang Ying vma_end_reservation(h, vma, haddr); 535957303d80SAndy Whitcroft 5360f83a275dSMel Gorman if (!(vma->vm_flags & VM_MAYSHARE)) 536157303d80SAndy Whitcroft pagecache_page = hugetlbfs_pagecache_page(h, 5362285b8dcaSHuang Ying vma, haddr); 536357303d80SAndy Whitcroft } 536457303d80SAndy Whitcroft 53650f792cf9SNaoya Horiguchi ptl = huge_pte_lock(h, mm, ptep); 53660fe6e20bSNaoya Horiguchi 53671e8f889bSDavid Gibson /* Check for a racing update before calling hugetlb_cow */ 5368b4d1d99fSDavid Gibson if (unlikely(!pte_same(entry, huge_ptep_get(ptep)))) 5369cb900f41SKirill A. Shutemov goto out_ptl; 5370b4d1d99fSDavid Gibson 53710f792cf9SNaoya Horiguchi /* 53720f792cf9SNaoya Horiguchi * hugetlb_cow() requires page locks of pte_page(entry) and 53730f792cf9SNaoya Horiguchi * pagecache_page, so here we need take the former one 53740f792cf9SNaoya Horiguchi * when page != pagecache_page or !pagecache_page. 53750f792cf9SNaoya Horiguchi */ 53760f792cf9SNaoya Horiguchi page = pte_page(entry); 53770f792cf9SNaoya Horiguchi if (page != pagecache_page) 53780f792cf9SNaoya Horiguchi if (!trylock_page(page)) { 53790f792cf9SNaoya Horiguchi need_wait_lock = 1; 53800f792cf9SNaoya Horiguchi goto out_ptl; 53810f792cf9SNaoya Horiguchi } 53820f792cf9SNaoya Horiguchi 53830f792cf9SNaoya Horiguchi get_page(page); 5384b4d1d99fSDavid Gibson 5385788c7df4SHugh Dickins if (flags & FAULT_FLAG_WRITE) { 5386106c992aSGerald Schaefer if (!huge_pte_write(entry)) { 5387974e6d66SHuang Ying ret = hugetlb_cow(mm, vma, address, ptep, 5388cb900f41SKirill A. Shutemov pagecache_page, ptl); 53890f792cf9SNaoya Horiguchi goto out_put_page; 5390b4d1d99fSDavid Gibson } 5391106c992aSGerald Schaefer entry = huge_pte_mkdirty(entry); 5392b4d1d99fSDavid Gibson } 5393b4d1d99fSDavid Gibson entry = pte_mkyoung(entry); 5394285b8dcaSHuang Ying if (huge_ptep_set_access_flags(vma, haddr, ptep, entry, 5395788c7df4SHugh Dickins flags & FAULT_FLAG_WRITE)) 5396285b8dcaSHuang Ying update_mmu_cache(vma, haddr, ptep); 53970f792cf9SNaoya Horiguchi out_put_page: 53980f792cf9SNaoya Horiguchi if (page != pagecache_page) 53990f792cf9SNaoya Horiguchi unlock_page(page); 54000f792cf9SNaoya Horiguchi put_page(page); 5401cb900f41SKirill A. Shutemov out_ptl: 5402cb900f41SKirill A. Shutemov spin_unlock(ptl); 540357303d80SAndy Whitcroft 540457303d80SAndy Whitcroft if (pagecache_page) { 540557303d80SAndy Whitcroft unlock_page(pagecache_page); 540657303d80SAndy Whitcroft put_page(pagecache_page); 540757303d80SAndy Whitcroft } 5408b4d1d99fSDavid Gibson out_mutex: 5409c672c7f2SMike Kravetz mutex_unlock(&hugetlb_fault_mutex_table[hash]); 5410c0d0381aSMike Kravetz i_mmap_unlock_read(mapping); 54110f792cf9SNaoya Horiguchi /* 54120f792cf9SNaoya Horiguchi * Generally it's safe to hold refcount during waiting page lock. But 54130f792cf9SNaoya Horiguchi * here we just wait to defer the next page fault to avoid busy loop and 54140f792cf9SNaoya Horiguchi * the page is not used after unlocked before returning from the current 54150f792cf9SNaoya Horiguchi * page fault. So we are safe from accessing freed page, even if we wait 54160f792cf9SNaoya Horiguchi * here without taking refcount. 54170f792cf9SNaoya Horiguchi */ 54180f792cf9SNaoya Horiguchi if (need_wait_lock) 54190f792cf9SNaoya Horiguchi wait_on_page_locked(page); 54201e8f889bSDavid Gibson return ret; 542186e5216fSAdam Litke } 542286e5216fSAdam Litke 5423714c1891SAxel Rasmussen #ifdef CONFIG_USERFAULTFD 54248fb5debcSMike Kravetz /* 54258fb5debcSMike Kravetz * Used by userfaultfd UFFDIO_COPY. Based on mcopy_atomic_pte with 54268fb5debcSMike Kravetz * modifications for huge pages. 54278fb5debcSMike Kravetz */ 54288fb5debcSMike Kravetz int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, 54298fb5debcSMike Kravetz pte_t *dst_pte, 54308fb5debcSMike Kravetz struct vm_area_struct *dst_vma, 54318fb5debcSMike Kravetz unsigned long dst_addr, 54328fb5debcSMike Kravetz unsigned long src_addr, 5433f6191471SAxel Rasmussen enum mcopy_atomic_mode mode, 54348fb5debcSMike Kravetz struct page **pagep) 54358fb5debcSMike Kravetz { 5436f6191471SAxel Rasmussen bool is_continue = (mode == MCOPY_ATOMIC_CONTINUE); 54378cc5fcbbSMina Almasry struct hstate *h = hstate_vma(dst_vma); 54388cc5fcbbSMina Almasry struct address_space *mapping = dst_vma->vm_file->f_mapping; 54398cc5fcbbSMina Almasry pgoff_t idx = vma_hugecache_offset(h, dst_vma, dst_addr); 54401e392147SAndrea Arcangeli unsigned long size; 54411c9e8defSMike Kravetz int vm_shared = dst_vma->vm_flags & VM_SHARED; 54428fb5debcSMike Kravetz pte_t _dst_pte; 54438fb5debcSMike Kravetz spinlock_t *ptl; 54448cc5fcbbSMina Almasry int ret = -ENOMEM; 54458fb5debcSMike Kravetz struct page *page; 5446f6191471SAxel Rasmussen int writable; 5447c7b1850dSMike Kravetz bool new_pagecache_page = false; 54488fb5debcSMike Kravetz 5449f6191471SAxel Rasmussen if (is_continue) { 5450f6191471SAxel Rasmussen ret = -EFAULT; 5451f6191471SAxel Rasmussen page = find_lock_page(mapping, idx); 5452f6191471SAxel Rasmussen if (!page) 5453f6191471SAxel Rasmussen goto out; 5454f6191471SAxel Rasmussen } else if (!*pagep) { 5455d84cf06eSMina Almasry /* If a page already exists, then it's UFFDIO_COPY for 5456d84cf06eSMina Almasry * a non-missing case. Return -EEXIST. 5457d84cf06eSMina Almasry */ 5458d84cf06eSMina Almasry if (vm_shared && 5459d84cf06eSMina Almasry hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { 5460d84cf06eSMina Almasry ret = -EEXIST; 54618fb5debcSMike Kravetz goto out; 5462d84cf06eSMina Almasry } 5463d84cf06eSMina Almasry 5464d84cf06eSMina Almasry page = alloc_huge_page(dst_vma, dst_addr, 0); 5465d84cf06eSMina Almasry if (IS_ERR(page)) { 5466d84cf06eSMina Almasry ret = -ENOMEM; 5467d84cf06eSMina Almasry goto out; 5468d84cf06eSMina Almasry } 54698fb5debcSMike Kravetz 54708fb5debcSMike Kravetz ret = copy_huge_page_from_user(page, 54718fb5debcSMike Kravetz (const void __user *) src_addr, 5472810a56b9SMike Kravetz pages_per_huge_page(h), false); 54738fb5debcSMike Kravetz 5474c1e8d7c6SMichel Lespinasse /* fallback to copy_from_user outside mmap_lock */ 54758fb5debcSMike Kravetz if (unlikely(ret)) { 54769e368259SAndrea Arcangeli ret = -ENOENT; 54778cc5fcbbSMina Almasry /* Free the allocated page which may have 54788cc5fcbbSMina Almasry * consumed a reservation. 54798cc5fcbbSMina Almasry */ 54808cc5fcbbSMina Almasry restore_reserve_on_error(h, dst_vma, dst_addr, page); 54818cc5fcbbSMina Almasry put_page(page); 54828cc5fcbbSMina Almasry 54838cc5fcbbSMina Almasry /* Allocate a temporary page to hold the copied 54848cc5fcbbSMina Almasry * contents. 54858cc5fcbbSMina Almasry */ 54868cc5fcbbSMina Almasry page = alloc_huge_page_vma(h, dst_vma, dst_addr); 54878cc5fcbbSMina Almasry if (!page) { 54888cc5fcbbSMina Almasry ret = -ENOMEM; 54898cc5fcbbSMina Almasry goto out; 54908cc5fcbbSMina Almasry } 54918fb5debcSMike Kravetz *pagep = page; 54928cc5fcbbSMina Almasry /* Set the outparam pagep and return to the caller to 54938cc5fcbbSMina Almasry * copy the contents outside the lock. Don't free the 54948cc5fcbbSMina Almasry * page. 54958cc5fcbbSMina Almasry */ 54968fb5debcSMike Kravetz goto out; 54978fb5debcSMike Kravetz } 54988fb5debcSMike Kravetz } else { 54998cc5fcbbSMina Almasry if (vm_shared && 55008cc5fcbbSMina Almasry hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { 55018cc5fcbbSMina Almasry put_page(*pagep); 55028cc5fcbbSMina Almasry ret = -EEXIST; 55038cc5fcbbSMina Almasry *pagep = NULL; 55048cc5fcbbSMina Almasry goto out; 55058cc5fcbbSMina Almasry } 55068cc5fcbbSMina Almasry 55078cc5fcbbSMina Almasry page = alloc_huge_page(dst_vma, dst_addr, 0); 55088cc5fcbbSMina Almasry if (IS_ERR(page)) { 55098cc5fcbbSMina Almasry ret = -ENOMEM; 55108cc5fcbbSMina Almasry *pagep = NULL; 55118cc5fcbbSMina Almasry goto out; 55128cc5fcbbSMina Almasry } 55138cc5fcbbSMina Almasry copy_huge_page(page, *pagep); 55148cc5fcbbSMina Almasry put_page(*pagep); 55158fb5debcSMike Kravetz *pagep = NULL; 55168fb5debcSMike Kravetz } 55178fb5debcSMike Kravetz 55188fb5debcSMike Kravetz /* 55198fb5debcSMike Kravetz * The memory barrier inside __SetPageUptodate makes sure that 55208fb5debcSMike Kravetz * preceding stores to the page contents become visible before 55218fb5debcSMike Kravetz * the set_pte_at() write. 55228fb5debcSMike Kravetz */ 55238fb5debcSMike Kravetz __SetPageUptodate(page); 55248fb5debcSMike Kravetz 5525f6191471SAxel Rasmussen /* Add shared, newly allocated pages to the page cache. */ 5526f6191471SAxel Rasmussen if (vm_shared && !is_continue) { 55271e392147SAndrea Arcangeli size = i_size_read(mapping->host) >> huge_page_shift(h); 55281e392147SAndrea Arcangeli ret = -EFAULT; 55291e392147SAndrea Arcangeli if (idx >= size) 55301e392147SAndrea Arcangeli goto out_release_nounlock; 55311c9e8defSMike Kravetz 55321e392147SAndrea Arcangeli /* 55331e392147SAndrea Arcangeli * Serialization between remove_inode_hugepages() and 55341e392147SAndrea Arcangeli * huge_add_to_page_cache() below happens through the 55351e392147SAndrea Arcangeli * hugetlb_fault_mutex_table that here must be hold by 55361e392147SAndrea Arcangeli * the caller. 55371e392147SAndrea Arcangeli */ 55381c9e8defSMike Kravetz ret = huge_add_to_page_cache(page, mapping, idx); 55391c9e8defSMike Kravetz if (ret) 55401c9e8defSMike Kravetz goto out_release_nounlock; 5541c7b1850dSMike Kravetz new_pagecache_page = true; 55421c9e8defSMike Kravetz } 55431c9e8defSMike Kravetz 55448fb5debcSMike Kravetz ptl = huge_pte_lockptr(h, dst_mm, dst_pte); 55458fb5debcSMike Kravetz spin_lock(ptl); 55468fb5debcSMike Kravetz 55471e392147SAndrea Arcangeli /* 55481e392147SAndrea Arcangeli * Recheck the i_size after holding PT lock to make sure not 55491e392147SAndrea Arcangeli * to leave any page mapped (as page_mapped()) beyond the end 55501e392147SAndrea Arcangeli * of the i_size (remove_inode_hugepages() is strict about 55511e392147SAndrea Arcangeli * enforcing that). If we bail out here, we'll also leave a 55521e392147SAndrea Arcangeli * page in the radix tree in the vm_shared case beyond the end 55531e392147SAndrea Arcangeli * of the i_size, but remove_inode_hugepages() will take care 55541e392147SAndrea Arcangeli * of it as soon as we drop the hugetlb_fault_mutex_table. 55551e392147SAndrea Arcangeli */ 55561e392147SAndrea Arcangeli size = i_size_read(mapping->host) >> huge_page_shift(h); 55571e392147SAndrea Arcangeli ret = -EFAULT; 55581e392147SAndrea Arcangeli if (idx >= size) 55591e392147SAndrea Arcangeli goto out_release_unlock; 55601e392147SAndrea Arcangeli 55618fb5debcSMike Kravetz ret = -EEXIST; 55628fb5debcSMike Kravetz if (!huge_pte_none(huge_ptep_get(dst_pte))) 55638fb5debcSMike Kravetz goto out_release_unlock; 55648fb5debcSMike Kravetz 55651c9e8defSMike Kravetz if (vm_shared) { 55661c9e8defSMike Kravetz page_dup_rmap(page, true); 55671c9e8defSMike Kravetz } else { 5568d6995da3SMike Kravetz ClearHPageRestoreReserve(page); 55698fb5debcSMike Kravetz hugepage_add_new_anon_rmap(page, dst_vma, dst_addr); 55701c9e8defSMike Kravetz } 55718fb5debcSMike Kravetz 5572f6191471SAxel Rasmussen /* For CONTINUE on a non-shared VMA, don't set VM_WRITE for CoW. */ 5573f6191471SAxel Rasmussen if (is_continue && !vm_shared) 5574f6191471SAxel Rasmussen writable = 0; 5575f6191471SAxel Rasmussen else 5576f6191471SAxel Rasmussen writable = dst_vma->vm_flags & VM_WRITE; 5577f6191471SAxel Rasmussen 5578f6191471SAxel Rasmussen _dst_pte = make_huge_pte(dst_vma, page, writable); 5579f6191471SAxel Rasmussen if (writable) 55808fb5debcSMike Kravetz _dst_pte = huge_pte_mkdirty(_dst_pte); 55818fb5debcSMike Kravetz _dst_pte = pte_mkyoung(_dst_pte); 55828fb5debcSMike Kravetz 55838fb5debcSMike Kravetz set_huge_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte); 55848fb5debcSMike Kravetz 55858fb5debcSMike Kravetz (void)huge_ptep_set_access_flags(dst_vma, dst_addr, dst_pte, _dst_pte, 55868fb5debcSMike Kravetz dst_vma->vm_flags & VM_WRITE); 55878fb5debcSMike Kravetz hugetlb_count_add(pages_per_huge_page(h), dst_mm); 55888fb5debcSMike Kravetz 55898fb5debcSMike Kravetz /* No need to invalidate - it was non-present before */ 55908fb5debcSMike Kravetz update_mmu_cache(dst_vma, dst_addr, dst_pte); 55918fb5debcSMike Kravetz 55928fb5debcSMike Kravetz spin_unlock(ptl); 5593f6191471SAxel Rasmussen if (!is_continue) 55948f251a3dSMike Kravetz SetHPageMigratable(page); 5595f6191471SAxel Rasmussen if (vm_shared || is_continue) 55961c9e8defSMike Kravetz unlock_page(page); 55978fb5debcSMike Kravetz ret = 0; 55988fb5debcSMike Kravetz out: 55998fb5debcSMike Kravetz return ret; 56008fb5debcSMike Kravetz out_release_unlock: 56018fb5debcSMike Kravetz spin_unlock(ptl); 5602f6191471SAxel Rasmussen if (vm_shared || is_continue) 56031c9e8defSMike Kravetz unlock_page(page); 56045af10dfdSAndrea Arcangeli out_release_nounlock: 5605c7b1850dSMike Kravetz if (!new_pagecache_page) 5606846be085SMike Kravetz restore_reserve_on_error(h, dst_vma, dst_addr, page); 56078fb5debcSMike Kravetz put_page(page); 56088fb5debcSMike Kravetz goto out; 56098fb5debcSMike Kravetz } 5610714c1891SAxel Rasmussen #endif /* CONFIG_USERFAULTFD */ 56118fb5debcSMike Kravetz 561282e5d378SJoao Martins static void record_subpages_vmas(struct page *page, struct vm_area_struct *vma, 561382e5d378SJoao Martins int refs, struct page **pages, 561482e5d378SJoao Martins struct vm_area_struct **vmas) 561582e5d378SJoao Martins { 561682e5d378SJoao Martins int nr; 561782e5d378SJoao Martins 561882e5d378SJoao Martins for (nr = 0; nr < refs; nr++) { 561982e5d378SJoao Martins if (likely(pages)) 562082e5d378SJoao Martins pages[nr] = mem_map_offset(page, nr); 562182e5d378SJoao Martins if (vmas) 562282e5d378SJoao Martins vmas[nr] = vma; 562382e5d378SJoao Martins } 562482e5d378SJoao Martins } 562582e5d378SJoao Martins 562628a35716SMichel Lespinasse long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, 562763551ae0SDavid Gibson struct page **pages, struct vm_area_struct **vmas, 562828a35716SMichel Lespinasse unsigned long *position, unsigned long *nr_pages, 56294f6da934SPeter Xu long i, unsigned int flags, int *locked) 563063551ae0SDavid Gibson { 5631d5d4b0aaSChen, Kenneth W unsigned long pfn_offset; 5632d5d4b0aaSChen, Kenneth W unsigned long vaddr = *position; 563328a35716SMichel Lespinasse unsigned long remainder = *nr_pages; 5634a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 56350fa5bc40SJoao Martins int err = -EFAULT, refs; 563663551ae0SDavid Gibson 563763551ae0SDavid Gibson while (vaddr < vma->vm_end && remainder) { 563863551ae0SDavid Gibson pte_t *pte; 5639cb900f41SKirill A. Shutemov spinlock_t *ptl = NULL; 56402a15efc9SHugh Dickins int absent; 564163551ae0SDavid Gibson struct page *page; 564263551ae0SDavid Gibson 56434c887265SAdam Litke /* 564402057967SDavid Rientjes * If we have a pending SIGKILL, don't keep faulting pages and 564502057967SDavid Rientjes * potentially allocating memory. 564602057967SDavid Rientjes */ 5647fa45f116SDavidlohr Bueso if (fatal_signal_pending(current)) { 564802057967SDavid Rientjes remainder = 0; 564902057967SDavid Rientjes break; 565002057967SDavid Rientjes } 565102057967SDavid Rientjes 565202057967SDavid Rientjes /* 56534c887265SAdam Litke * Some archs (sparc64, sh*) have multiple pte_ts to 56542a15efc9SHugh Dickins * each hugepage. We have to make sure we get the 56554c887265SAdam Litke * first, for the page indexing below to work. 5656cb900f41SKirill A. Shutemov * 5657cb900f41SKirill A. Shutemov * Note that page table lock is not held when pte is null. 56584c887265SAdam Litke */ 56597868a208SPunit Agrawal pte = huge_pte_offset(mm, vaddr & huge_page_mask(h), 56607868a208SPunit Agrawal huge_page_size(h)); 5661cb900f41SKirill A. Shutemov if (pte) 5662cb900f41SKirill A. Shutemov ptl = huge_pte_lock(h, mm, pte); 56632a15efc9SHugh Dickins absent = !pte || huge_pte_none(huge_ptep_get(pte)); 566463551ae0SDavid Gibson 56652a15efc9SHugh Dickins /* 56662a15efc9SHugh Dickins * When coredumping, it suits get_dump_page if we just return 56673ae77f43SHugh Dickins * an error where there's an empty slot with no huge pagecache 56683ae77f43SHugh Dickins * to back it. This way, we avoid allocating a hugepage, and 56693ae77f43SHugh Dickins * the sparse dumpfile avoids allocating disk blocks, but its 56703ae77f43SHugh Dickins * huge holes still show up with zeroes where they need to be. 56712a15efc9SHugh Dickins */ 56723ae77f43SHugh Dickins if (absent && (flags & FOLL_DUMP) && 56733ae77f43SHugh Dickins !hugetlbfs_pagecache_present(h, vma, vaddr)) { 5674cb900f41SKirill A. Shutemov if (pte) 5675cb900f41SKirill A. Shutemov spin_unlock(ptl); 56762a15efc9SHugh Dickins remainder = 0; 56772a15efc9SHugh Dickins break; 56782a15efc9SHugh Dickins } 56792a15efc9SHugh Dickins 56809cc3a5bdSNaoya Horiguchi /* 56819cc3a5bdSNaoya Horiguchi * We need call hugetlb_fault for both hugepages under migration 56829cc3a5bdSNaoya Horiguchi * (in which case hugetlb_fault waits for the migration,) and 56839cc3a5bdSNaoya Horiguchi * hwpoisoned hugepages (in which case we need to prevent the 56849cc3a5bdSNaoya Horiguchi * caller from accessing to them.) In order to do this, we use 56859cc3a5bdSNaoya Horiguchi * here is_swap_pte instead of is_hugetlb_entry_migration and 56869cc3a5bdSNaoya Horiguchi * is_hugetlb_entry_hwpoisoned. This is because it simply covers 56879cc3a5bdSNaoya Horiguchi * both cases, and because we can't follow correct pages 56889cc3a5bdSNaoya Horiguchi * directly from any kind of swap entries. 56899cc3a5bdSNaoya Horiguchi */ 56909cc3a5bdSNaoya Horiguchi if (absent || is_swap_pte(huge_ptep_get(pte)) || 5691106c992aSGerald Schaefer ((flags & FOLL_WRITE) && 5692106c992aSGerald Schaefer !huge_pte_write(huge_ptep_get(pte)))) { 56932b740303SSouptick Joarder vm_fault_t ret; 569487ffc118SAndrea Arcangeli unsigned int fault_flags = 0; 56954c887265SAdam Litke 5696cb900f41SKirill A. Shutemov if (pte) 5697cb900f41SKirill A. Shutemov spin_unlock(ptl); 569887ffc118SAndrea Arcangeli if (flags & FOLL_WRITE) 569987ffc118SAndrea Arcangeli fault_flags |= FAULT_FLAG_WRITE; 57004f6da934SPeter Xu if (locked) 570171335f37SPeter Xu fault_flags |= FAULT_FLAG_ALLOW_RETRY | 570271335f37SPeter Xu FAULT_FLAG_KILLABLE; 570387ffc118SAndrea Arcangeli if (flags & FOLL_NOWAIT) 570487ffc118SAndrea Arcangeli fault_flags |= FAULT_FLAG_ALLOW_RETRY | 570587ffc118SAndrea Arcangeli FAULT_FLAG_RETRY_NOWAIT; 570687ffc118SAndrea Arcangeli if (flags & FOLL_TRIED) { 57074426e945SPeter Xu /* 57084426e945SPeter Xu * Note: FAULT_FLAG_ALLOW_RETRY and 57094426e945SPeter Xu * FAULT_FLAG_TRIED can co-exist 57104426e945SPeter Xu */ 571187ffc118SAndrea Arcangeli fault_flags |= FAULT_FLAG_TRIED; 571287ffc118SAndrea Arcangeli } 571387ffc118SAndrea Arcangeli ret = hugetlb_fault(mm, vma, vaddr, fault_flags); 571487ffc118SAndrea Arcangeli if (ret & VM_FAULT_ERROR) { 57152be7cfedSDaniel Jordan err = vm_fault_to_errno(ret, flags); 57161c59827dSHugh Dickins remainder = 0; 57171c59827dSHugh Dickins break; 57181c59827dSHugh Dickins } 571987ffc118SAndrea Arcangeli if (ret & VM_FAULT_RETRY) { 57204f6da934SPeter Xu if (locked && 57211ac25013SAndrea Arcangeli !(fault_flags & FAULT_FLAG_RETRY_NOWAIT)) 57224f6da934SPeter Xu *locked = 0; 572387ffc118SAndrea Arcangeli *nr_pages = 0; 572487ffc118SAndrea Arcangeli /* 572587ffc118SAndrea Arcangeli * VM_FAULT_RETRY must not return an 572687ffc118SAndrea Arcangeli * error, it will return zero 572787ffc118SAndrea Arcangeli * instead. 572887ffc118SAndrea Arcangeli * 572987ffc118SAndrea Arcangeli * No need to update "position" as the 573087ffc118SAndrea Arcangeli * caller will not check it after 573187ffc118SAndrea Arcangeli * *nr_pages is set to 0. 573287ffc118SAndrea Arcangeli */ 573387ffc118SAndrea Arcangeli return i; 573487ffc118SAndrea Arcangeli } 573587ffc118SAndrea Arcangeli continue; 573687ffc118SAndrea Arcangeli } 573763551ae0SDavid Gibson 5738a5516438SAndi Kleen pfn_offset = (vaddr & ~huge_page_mask(h)) >> PAGE_SHIFT; 57397f2e9525SGerald Schaefer page = pte_page(huge_ptep_get(pte)); 57408fde12caSLinus Torvalds 57418fde12caSLinus Torvalds /* 5742acbfb087SZhigang Lu * If subpage information not requested, update counters 5743acbfb087SZhigang Lu * and skip the same_page loop below. 5744acbfb087SZhigang Lu */ 5745acbfb087SZhigang Lu if (!pages && !vmas && !pfn_offset && 5746acbfb087SZhigang Lu (vaddr + huge_page_size(h) < vma->vm_end) && 5747acbfb087SZhigang Lu (remainder >= pages_per_huge_page(h))) { 5748acbfb087SZhigang Lu vaddr += huge_page_size(h); 5749acbfb087SZhigang Lu remainder -= pages_per_huge_page(h); 5750acbfb087SZhigang Lu i += pages_per_huge_page(h); 5751acbfb087SZhigang Lu spin_unlock(ptl); 5752acbfb087SZhigang Lu continue; 5753acbfb087SZhigang Lu } 5754acbfb087SZhigang Lu 5755d08af0a5SJoao Martins /* vaddr may not be aligned to PAGE_SIZE */ 5756d08af0a5SJoao Martins refs = min3(pages_per_huge_page(h) - pfn_offset, remainder, 5757d08af0a5SJoao Martins (vma->vm_end - ALIGN_DOWN(vaddr, PAGE_SIZE)) >> PAGE_SHIFT); 57580fa5bc40SJoao Martins 575982e5d378SJoao Martins if (pages || vmas) 576082e5d378SJoao Martins record_subpages_vmas(mem_map_offset(page, pfn_offset), 576182e5d378SJoao Martins vma, refs, 576282e5d378SJoao Martins likely(pages) ? pages + i : NULL, 576382e5d378SJoao Martins vmas ? vmas + i : NULL); 576463551ae0SDavid Gibson 576582e5d378SJoao Martins if (pages) { 57660fa5bc40SJoao Martins /* 57670fa5bc40SJoao Martins * try_grab_compound_head() should always succeed here, 57680fa5bc40SJoao Martins * because: a) we hold the ptl lock, and b) we've just 57690fa5bc40SJoao Martins * checked that the huge page is present in the page 57700fa5bc40SJoao Martins * tables. If the huge page is present, then the tail 57710fa5bc40SJoao Martins * pages must also be present. The ptl prevents the 57720fa5bc40SJoao Martins * head page and tail pages from being rearranged in 57730fa5bc40SJoao Martins * any way. So this page must be available at this 57740fa5bc40SJoao Martins * point, unless the page refcount overflowed: 57750fa5bc40SJoao Martins */ 577682e5d378SJoao Martins if (WARN_ON_ONCE(!try_grab_compound_head(pages[i], 57770fa5bc40SJoao Martins refs, 57780fa5bc40SJoao Martins flags))) { 57790fa5bc40SJoao Martins spin_unlock(ptl); 57800fa5bc40SJoao Martins remainder = 0; 57810fa5bc40SJoao Martins err = -ENOMEM; 57820fa5bc40SJoao Martins break; 57830fa5bc40SJoao Martins } 5784d5d4b0aaSChen, Kenneth W } 578582e5d378SJoao Martins 578682e5d378SJoao Martins vaddr += (refs << PAGE_SHIFT); 578782e5d378SJoao Martins remainder -= refs; 578882e5d378SJoao Martins i += refs; 578982e5d378SJoao Martins 5790cb900f41SKirill A. Shutemov spin_unlock(ptl); 579163551ae0SDavid Gibson } 579228a35716SMichel Lespinasse *nr_pages = remainder; 579387ffc118SAndrea Arcangeli /* 579487ffc118SAndrea Arcangeli * setting position is actually required only if remainder is 579587ffc118SAndrea Arcangeli * not zero but it's faster not to add a "if (remainder)" 579687ffc118SAndrea Arcangeli * branch. 579787ffc118SAndrea Arcangeli */ 579863551ae0SDavid Gibson *position = vaddr; 579963551ae0SDavid Gibson 58002be7cfedSDaniel Jordan return i ? i : err; 580163551ae0SDavid Gibson } 58028f860591SZhang, Yanmin 58037da4d641SPeter Zijlstra unsigned long hugetlb_change_protection(struct vm_area_struct *vma, 58048f860591SZhang, Yanmin unsigned long address, unsigned long end, pgprot_t newprot) 58058f860591SZhang, Yanmin { 58068f860591SZhang, Yanmin struct mm_struct *mm = vma->vm_mm; 58078f860591SZhang, Yanmin unsigned long start = address; 58088f860591SZhang, Yanmin pte_t *ptep; 58098f860591SZhang, Yanmin pte_t pte; 5810a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 58117da4d641SPeter Zijlstra unsigned long pages = 0; 5812dff11abeSMike Kravetz bool shared_pmd = false; 5813ac46d4f3SJérôme Glisse struct mmu_notifier_range range; 5814dff11abeSMike Kravetz 5815dff11abeSMike Kravetz /* 5816dff11abeSMike Kravetz * In the case of shared PMDs, the area to flush could be beyond 5817ac46d4f3SJérôme Glisse * start/end. Set range.start/range.end to cover the maximum possible 5818dff11abeSMike Kravetz * range if PMD sharing is possible. 5819dff11abeSMike Kravetz */ 58207269f999SJérôme Glisse mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_VMA, 58217269f999SJérôme Glisse 0, vma, mm, start, end); 5822ac46d4f3SJérôme Glisse adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); 58238f860591SZhang, Yanmin 58248f860591SZhang, Yanmin BUG_ON(address >= end); 5825ac46d4f3SJérôme Glisse flush_cache_range(vma, range.start, range.end); 58268f860591SZhang, Yanmin 5827ac46d4f3SJérôme Glisse mmu_notifier_invalidate_range_start(&range); 582883cde9e8SDavidlohr Bueso i_mmap_lock_write(vma->vm_file->f_mapping); 5829a5516438SAndi Kleen for (; address < end; address += huge_page_size(h)) { 5830cb900f41SKirill A. Shutemov spinlock_t *ptl; 58317868a208SPunit Agrawal ptep = huge_pte_offset(mm, address, huge_page_size(h)); 58328f860591SZhang, Yanmin if (!ptep) 58338f860591SZhang, Yanmin continue; 5834cb900f41SKirill A. Shutemov ptl = huge_pte_lock(h, mm, ptep); 583534ae204fSMike Kravetz if (huge_pmd_unshare(mm, vma, &address, ptep)) { 58367da4d641SPeter Zijlstra pages++; 5837cb900f41SKirill A. Shutemov spin_unlock(ptl); 5838dff11abeSMike Kravetz shared_pmd = true; 583939dde65cSChen, Kenneth W continue; 58407da4d641SPeter Zijlstra } 5841a8bda28dSNaoya Horiguchi pte = huge_ptep_get(ptep); 5842a8bda28dSNaoya Horiguchi if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { 5843a8bda28dSNaoya Horiguchi spin_unlock(ptl); 5844a8bda28dSNaoya Horiguchi continue; 5845a8bda28dSNaoya Horiguchi } 5846a8bda28dSNaoya Horiguchi if (unlikely(is_hugetlb_entry_migration(pte))) { 5847a8bda28dSNaoya Horiguchi swp_entry_t entry = pte_to_swp_entry(pte); 5848a8bda28dSNaoya Horiguchi 58494dd845b5SAlistair Popple if (is_writable_migration_entry(entry)) { 5850a8bda28dSNaoya Horiguchi pte_t newpte; 5851a8bda28dSNaoya Horiguchi 58524dd845b5SAlistair Popple entry = make_readable_migration_entry( 58534dd845b5SAlistair Popple swp_offset(entry)); 5854a8bda28dSNaoya Horiguchi newpte = swp_entry_to_pte(entry); 5855e5251fd4SPunit Agrawal set_huge_swap_pte_at(mm, address, ptep, 5856e5251fd4SPunit Agrawal newpte, huge_page_size(h)); 5857a8bda28dSNaoya Horiguchi pages++; 5858a8bda28dSNaoya Horiguchi } 5859a8bda28dSNaoya Horiguchi spin_unlock(ptl); 5860a8bda28dSNaoya Horiguchi continue; 5861a8bda28dSNaoya Horiguchi } 5862a8bda28dSNaoya Horiguchi if (!huge_pte_none(pte)) { 5863023bdd00SAneesh Kumar K.V pte_t old_pte; 586479c1c594SChristophe Leroy unsigned int shift = huge_page_shift(hstate_vma(vma)); 5865023bdd00SAneesh Kumar K.V 5866023bdd00SAneesh Kumar K.V old_pte = huge_ptep_modify_prot_start(vma, address, ptep); 5867023bdd00SAneesh Kumar K.V pte = pte_mkhuge(huge_pte_modify(old_pte, newprot)); 586879c1c594SChristophe Leroy pte = arch_make_huge_pte(pte, shift, vma->vm_flags); 5869023bdd00SAneesh Kumar K.V huge_ptep_modify_prot_commit(vma, address, ptep, old_pte, pte); 58707da4d641SPeter Zijlstra pages++; 58718f860591SZhang, Yanmin } 5872cb900f41SKirill A. Shutemov spin_unlock(ptl); 58738f860591SZhang, Yanmin } 5874d833352aSMel Gorman /* 5875c8c06efaSDavidlohr Bueso * Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare 5876d833352aSMel Gorman * may have cleared our pud entry and done put_page on the page table: 5877c8c06efaSDavidlohr Bueso * once we release i_mmap_rwsem, another task can do the final put_page 5878dff11abeSMike Kravetz * and that page table be reused and filled with junk. If we actually 5879dff11abeSMike Kravetz * did unshare a page of pmds, flush the range corresponding to the pud. 5880d833352aSMel Gorman */ 5881dff11abeSMike Kravetz if (shared_pmd) 5882ac46d4f3SJérôme Glisse flush_hugetlb_tlb_range(vma, range.start, range.end); 5883dff11abeSMike Kravetz else 58845491ae7bSAneesh Kumar K.V flush_hugetlb_tlb_range(vma, start, end); 58850f10851eSJérôme Glisse /* 58860f10851eSJérôme Glisse * No need to call mmu_notifier_invalidate_range() we are downgrading 58870f10851eSJérôme Glisse * page table protection not changing it to point to a new page. 58880f10851eSJérôme Glisse * 5889ad56b738SMike Rapoport * See Documentation/vm/mmu_notifier.rst 58900f10851eSJérôme Glisse */ 589183cde9e8SDavidlohr Bueso i_mmap_unlock_write(vma->vm_file->f_mapping); 5892ac46d4f3SJérôme Glisse mmu_notifier_invalidate_range_end(&range); 58937da4d641SPeter Zijlstra 58947da4d641SPeter Zijlstra return pages << h->order; 58958f860591SZhang, Yanmin } 58968f860591SZhang, Yanmin 589733b8f84aSMike Kravetz /* Return true if reservation was successful, false otherwise. */ 589833b8f84aSMike Kravetz bool hugetlb_reserve_pages(struct inode *inode, 5899a1e78772SMel Gorman long from, long to, 59005a6fe125SMel Gorman struct vm_area_struct *vma, 5901ca16d140SKOSAKI Motohiro vm_flags_t vm_flags) 5902e4e574b7SAdam Litke { 590333b8f84aSMike Kravetz long chg, add = -1; 5904a5516438SAndi Kleen struct hstate *h = hstate_inode(inode); 590590481622SDavid Gibson struct hugepage_subpool *spool = subpool_inode(inode); 59069119a41eSJoonsoo Kim struct resv_map *resv_map; 5907075a61d0SMina Almasry struct hugetlb_cgroup *h_cg = NULL; 59080db9d74eSMina Almasry long gbl_reserve, regions_needed = 0; 5909e4e574b7SAdam Litke 591063489f8eSMike Kravetz /* This should never happen */ 591163489f8eSMike Kravetz if (from > to) { 591263489f8eSMike Kravetz VM_WARN(1, "%s called with a negative range\n", __func__); 591333b8f84aSMike Kravetz return false; 591463489f8eSMike Kravetz } 591563489f8eSMike Kravetz 5916a1e78772SMel Gorman /* 591717c9d12eSMel Gorman * Only apply hugepage reservation if asked. At fault time, an 591817c9d12eSMel Gorman * attempt will be made for VM_NORESERVE to allocate a page 591990481622SDavid Gibson * without using reserves 592017c9d12eSMel Gorman */ 5921ca16d140SKOSAKI Motohiro if (vm_flags & VM_NORESERVE) 592233b8f84aSMike Kravetz return true; 592317c9d12eSMel Gorman 592417c9d12eSMel Gorman /* 5925a1e78772SMel Gorman * Shared mappings base their reservation on the number of pages that 5926a1e78772SMel Gorman * are already allocated on behalf of the file. Private mappings need 5927a1e78772SMel Gorman * to reserve the full area even if read-only as mprotect() may be 5928a1e78772SMel Gorman * called to make the mapping read-write. Assume !vma is a shm mapping 5929a1e78772SMel Gorman */ 59309119a41eSJoonsoo Kim if (!vma || vma->vm_flags & VM_MAYSHARE) { 5931f27a5136SMike Kravetz /* 5932f27a5136SMike Kravetz * resv_map can not be NULL as hugetlb_reserve_pages is only 5933f27a5136SMike Kravetz * called for inodes for which resv_maps were created (see 5934f27a5136SMike Kravetz * hugetlbfs_get_inode). 5935f27a5136SMike Kravetz */ 59364e35f483SJoonsoo Kim resv_map = inode_resv_map(inode); 59379119a41eSJoonsoo Kim 59380db9d74eSMina Almasry chg = region_chg(resv_map, from, to, ®ions_needed); 59399119a41eSJoonsoo Kim 59409119a41eSJoonsoo Kim } else { 5941e9fe92aeSMina Almasry /* Private mapping. */ 59429119a41eSJoonsoo Kim resv_map = resv_map_alloc(); 59435a6fe125SMel Gorman if (!resv_map) 594433b8f84aSMike Kravetz return false; 59455a6fe125SMel Gorman 594617c9d12eSMel Gorman chg = to - from; 594717c9d12eSMel Gorman 59485a6fe125SMel Gorman set_vma_resv_map(vma, resv_map); 59495a6fe125SMel Gorman set_vma_resv_flags(vma, HPAGE_RESV_OWNER); 59505a6fe125SMel Gorman } 59515a6fe125SMel Gorman 595233b8f84aSMike Kravetz if (chg < 0) 5953c50ac050SDave Hansen goto out_err; 595417c9d12eSMel Gorman 595533b8f84aSMike Kravetz if (hugetlb_cgroup_charge_cgroup_rsvd(hstate_index(h), 595633b8f84aSMike Kravetz chg * pages_per_huge_page(h), &h_cg) < 0) 5957075a61d0SMina Almasry goto out_err; 5958075a61d0SMina Almasry 5959075a61d0SMina Almasry if (vma && !(vma->vm_flags & VM_MAYSHARE) && h_cg) { 5960075a61d0SMina Almasry /* For private mappings, the hugetlb_cgroup uncharge info hangs 5961075a61d0SMina Almasry * of the resv_map. 5962075a61d0SMina Almasry */ 5963075a61d0SMina Almasry resv_map_set_hugetlb_cgroup_uncharge_info(resv_map, h_cg, h); 5964075a61d0SMina Almasry } 5965075a61d0SMina Almasry 59661c5ecae3SMike Kravetz /* 59671c5ecae3SMike Kravetz * There must be enough pages in the subpool for the mapping. If 59681c5ecae3SMike Kravetz * the subpool has a minimum size, there may be some global 59691c5ecae3SMike Kravetz * reservations already in place (gbl_reserve). 59701c5ecae3SMike Kravetz */ 59711c5ecae3SMike Kravetz gbl_reserve = hugepage_subpool_get_pages(spool, chg); 597233b8f84aSMike Kravetz if (gbl_reserve < 0) 5973075a61d0SMina Almasry goto out_uncharge_cgroup; 597417c9d12eSMel Gorman 597517c9d12eSMel Gorman /* 597617c9d12eSMel Gorman * Check enough hugepages are available for the reservation. 597790481622SDavid Gibson * Hand the pages back to the subpool if there are not 597817c9d12eSMel Gorman */ 597933b8f84aSMike Kravetz if (hugetlb_acct_memory(h, gbl_reserve) < 0) 5980075a61d0SMina Almasry goto out_put_pages; 598117c9d12eSMel Gorman 598217c9d12eSMel Gorman /* 598317c9d12eSMel Gorman * Account for the reservations made. Shared mappings record regions 598417c9d12eSMel Gorman * that have reservations as they are shared by multiple VMAs. 598517c9d12eSMel Gorman * When the last VMA disappears, the region map says how much 598617c9d12eSMel Gorman * the reservation was and the page cache tells how much of 598717c9d12eSMel Gorman * the reservation was consumed. Private mappings are per-VMA and 598817c9d12eSMel Gorman * only the consumed reservations are tracked. When the VMA 598917c9d12eSMel Gorman * disappears, the original reservation is the VMA size and the 599017c9d12eSMel Gorman * consumed reservations are stored in the map. Hence, nothing 599117c9d12eSMel Gorman * else has to be done for private mappings here 599217c9d12eSMel Gorman */ 599333039678SMike Kravetz if (!vma || vma->vm_flags & VM_MAYSHARE) { 5994075a61d0SMina Almasry add = region_add(resv_map, from, to, regions_needed, h, h_cg); 599533039678SMike Kravetz 59960db9d74eSMina Almasry if (unlikely(add < 0)) { 59970db9d74eSMina Almasry hugetlb_acct_memory(h, -gbl_reserve); 5998075a61d0SMina Almasry goto out_put_pages; 59990db9d74eSMina Almasry } else if (unlikely(chg > add)) { 600033039678SMike Kravetz /* 600133039678SMike Kravetz * pages in this range were added to the reserve 600233039678SMike Kravetz * map between region_chg and region_add. This 600333039678SMike Kravetz * indicates a race with alloc_huge_page. Adjust 600433039678SMike Kravetz * the subpool and reserve counts modified above 600533039678SMike Kravetz * based on the difference. 600633039678SMike Kravetz */ 600733039678SMike Kravetz long rsv_adjust; 600833039678SMike Kravetz 6009d85aecf2SMiaohe Lin /* 6010d85aecf2SMiaohe Lin * hugetlb_cgroup_uncharge_cgroup_rsvd() will put the 6011d85aecf2SMiaohe Lin * reference to h_cg->css. See comment below for detail. 6012d85aecf2SMiaohe Lin */ 6013075a61d0SMina Almasry hugetlb_cgroup_uncharge_cgroup_rsvd( 6014075a61d0SMina Almasry hstate_index(h), 6015075a61d0SMina Almasry (chg - add) * pages_per_huge_page(h), h_cg); 6016075a61d0SMina Almasry 601733039678SMike Kravetz rsv_adjust = hugepage_subpool_put_pages(spool, 601833039678SMike Kravetz chg - add); 601933039678SMike Kravetz hugetlb_acct_memory(h, -rsv_adjust); 6020d85aecf2SMiaohe Lin } else if (h_cg) { 6021d85aecf2SMiaohe Lin /* 6022d85aecf2SMiaohe Lin * The file_regions will hold their own reference to 6023d85aecf2SMiaohe Lin * h_cg->css. So we should release the reference held 6024d85aecf2SMiaohe Lin * via hugetlb_cgroup_charge_cgroup_rsvd() when we are 6025d85aecf2SMiaohe Lin * done. 6026d85aecf2SMiaohe Lin */ 6027d85aecf2SMiaohe Lin hugetlb_cgroup_put_rsvd_cgroup(h_cg); 602833039678SMike Kravetz } 602933039678SMike Kravetz } 603033b8f84aSMike Kravetz return true; 603133b8f84aSMike Kravetz 6032075a61d0SMina Almasry out_put_pages: 6033075a61d0SMina Almasry /* put back original number of pages, chg */ 6034075a61d0SMina Almasry (void)hugepage_subpool_put_pages(spool, chg); 6035075a61d0SMina Almasry out_uncharge_cgroup: 6036075a61d0SMina Almasry hugetlb_cgroup_uncharge_cgroup_rsvd(hstate_index(h), 6037075a61d0SMina Almasry chg * pages_per_huge_page(h), h_cg); 6038c50ac050SDave Hansen out_err: 60395e911373SMike Kravetz if (!vma || vma->vm_flags & VM_MAYSHARE) 60400db9d74eSMina Almasry /* Only call region_abort if the region_chg succeeded but the 60410db9d74eSMina Almasry * region_add failed or didn't run. 60420db9d74eSMina Almasry */ 60430db9d74eSMina Almasry if (chg >= 0 && add < 0) 60440db9d74eSMina Almasry region_abort(resv_map, from, to, regions_needed); 6045f031dd27SJoonsoo Kim if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) 6046f031dd27SJoonsoo Kim kref_put(&resv_map->refs, resv_map_release); 604733b8f84aSMike Kravetz return false; 6048a43a8c39SChen, Kenneth W } 6049a43a8c39SChen, Kenneth W 6050b5cec28dSMike Kravetz long hugetlb_unreserve_pages(struct inode *inode, long start, long end, 6051b5cec28dSMike Kravetz long freed) 6052a43a8c39SChen, Kenneth W { 6053a5516438SAndi Kleen struct hstate *h = hstate_inode(inode); 60544e35f483SJoonsoo Kim struct resv_map *resv_map = inode_resv_map(inode); 60559119a41eSJoonsoo Kim long chg = 0; 605690481622SDavid Gibson struct hugepage_subpool *spool = subpool_inode(inode); 60571c5ecae3SMike Kravetz long gbl_reserve; 605845c682a6SKen Chen 6059f27a5136SMike Kravetz /* 6060f27a5136SMike Kravetz * Since this routine can be called in the evict inode path for all 6061f27a5136SMike Kravetz * hugetlbfs inodes, resv_map could be NULL. 6062f27a5136SMike Kravetz */ 6063b5cec28dSMike Kravetz if (resv_map) { 6064b5cec28dSMike Kravetz chg = region_del(resv_map, start, end); 6065b5cec28dSMike Kravetz /* 6066b5cec28dSMike Kravetz * region_del() can fail in the rare case where a region 6067b5cec28dSMike Kravetz * must be split and another region descriptor can not be 6068b5cec28dSMike Kravetz * allocated. If end == LONG_MAX, it will not fail. 6069b5cec28dSMike Kravetz */ 6070b5cec28dSMike Kravetz if (chg < 0) 6071b5cec28dSMike Kravetz return chg; 6072b5cec28dSMike Kravetz } 6073b5cec28dSMike Kravetz 607445c682a6SKen Chen spin_lock(&inode->i_lock); 6075e4c6f8beSEric Sandeen inode->i_blocks -= (blocks_per_huge_page(h) * freed); 607645c682a6SKen Chen spin_unlock(&inode->i_lock); 607745c682a6SKen Chen 60781c5ecae3SMike Kravetz /* 60791c5ecae3SMike Kravetz * If the subpool has a minimum size, the number of global 60801c5ecae3SMike Kravetz * reservations to be released may be adjusted. 6081dddf31a4SMiaohe Lin * 6082dddf31a4SMiaohe Lin * Note that !resv_map implies freed == 0. So (chg - freed) 6083dddf31a4SMiaohe Lin * won't go negative. 60841c5ecae3SMike Kravetz */ 60851c5ecae3SMike Kravetz gbl_reserve = hugepage_subpool_put_pages(spool, (chg - freed)); 60861c5ecae3SMike Kravetz hugetlb_acct_memory(h, -gbl_reserve); 6087b5cec28dSMike Kravetz 6088b5cec28dSMike Kravetz return 0; 6089a43a8c39SChen, Kenneth W } 609093f70f90SNaoya Horiguchi 60913212b535SSteve Capper #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE 60923212b535SSteve Capper static unsigned long page_table_shareable(struct vm_area_struct *svma, 60933212b535SSteve Capper struct vm_area_struct *vma, 60943212b535SSteve Capper unsigned long addr, pgoff_t idx) 60953212b535SSteve Capper { 60963212b535SSteve Capper unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) + 60973212b535SSteve Capper svma->vm_start; 60983212b535SSteve Capper unsigned long sbase = saddr & PUD_MASK; 60993212b535SSteve Capper unsigned long s_end = sbase + PUD_SIZE; 61003212b535SSteve Capper 61013212b535SSteve Capper /* Allow segments to share if only one is marked locked */ 6102de60f5f1SEric B Munson unsigned long vm_flags = vma->vm_flags & VM_LOCKED_CLEAR_MASK; 6103de60f5f1SEric B Munson unsigned long svm_flags = svma->vm_flags & VM_LOCKED_CLEAR_MASK; 61043212b535SSteve Capper 61053212b535SSteve Capper /* 61063212b535SSteve Capper * match the virtual addresses, permission and the alignment of the 61073212b535SSteve Capper * page table page. 61083212b535SSteve Capper */ 61093212b535SSteve Capper if (pmd_index(addr) != pmd_index(saddr) || 61103212b535SSteve Capper vm_flags != svm_flags || 611107e51edfSMiaohe Lin !range_in_vma(svma, sbase, s_end)) 61123212b535SSteve Capper return 0; 61133212b535SSteve Capper 61143212b535SSteve Capper return saddr; 61153212b535SSteve Capper } 61163212b535SSteve Capper 611731aafb45SNicholas Krause static bool vma_shareable(struct vm_area_struct *vma, unsigned long addr) 61183212b535SSteve Capper { 61193212b535SSteve Capper unsigned long base = addr & PUD_MASK; 61203212b535SSteve Capper unsigned long end = base + PUD_SIZE; 61213212b535SSteve Capper 61223212b535SSteve Capper /* 61233212b535SSteve Capper * check on proper vm_flags and page table alignment 61243212b535SSteve Capper */ 6125017b1660SMike Kravetz if (vma->vm_flags & VM_MAYSHARE && range_in_vma(vma, base, end)) 612631aafb45SNicholas Krause return true; 612731aafb45SNicholas Krause return false; 61283212b535SSteve Capper } 61293212b535SSteve Capper 6130c1991e07SPeter Xu bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr) 6131c1991e07SPeter Xu { 6132c1991e07SPeter Xu #ifdef CONFIG_USERFAULTFD 6133c1991e07SPeter Xu if (uffd_disable_huge_pmd_share(vma)) 6134c1991e07SPeter Xu return false; 6135c1991e07SPeter Xu #endif 6136c1991e07SPeter Xu return vma_shareable(vma, addr); 6137c1991e07SPeter Xu } 6138c1991e07SPeter Xu 61393212b535SSteve Capper /* 6140017b1660SMike Kravetz * Determine if start,end range within vma could be mapped by shared pmd. 6141017b1660SMike Kravetz * If yes, adjust start and end to cover range associated with possible 6142017b1660SMike Kravetz * shared pmd mappings. 6143017b1660SMike Kravetz */ 6144017b1660SMike Kravetz void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, 6145017b1660SMike Kravetz unsigned long *start, unsigned long *end) 6146017b1660SMike Kravetz { 6147a1ba9da8SLi Xinhai unsigned long v_start = ALIGN(vma->vm_start, PUD_SIZE), 6148a1ba9da8SLi Xinhai v_end = ALIGN_DOWN(vma->vm_end, PUD_SIZE); 6149017b1660SMike Kravetz 6150a1ba9da8SLi Xinhai /* 6151f0953a1bSIngo Molnar * vma needs to span at least one aligned PUD size, and the range 6152f0953a1bSIngo Molnar * must be at least partially within in. 6153a1ba9da8SLi Xinhai */ 6154a1ba9da8SLi Xinhai if (!(vma->vm_flags & VM_MAYSHARE) || !(v_end > v_start) || 6155a1ba9da8SLi Xinhai (*end <= v_start) || (*start >= v_end)) 6156017b1660SMike Kravetz return; 6157017b1660SMike Kravetz 615875802ca6SPeter Xu /* Extend the range to be PUD aligned for a worst case scenario */ 6159a1ba9da8SLi Xinhai if (*start > v_start) 6160a1ba9da8SLi Xinhai *start = ALIGN_DOWN(*start, PUD_SIZE); 6161017b1660SMike Kravetz 6162a1ba9da8SLi Xinhai if (*end < v_end) 6163a1ba9da8SLi Xinhai *end = ALIGN(*end, PUD_SIZE); 6164017b1660SMike Kravetz } 6165017b1660SMike Kravetz 6166017b1660SMike Kravetz /* 61673212b535SSteve Capper * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() 61683212b535SSteve Capper * and returns the corresponding pte. While this is not necessary for the 61693212b535SSteve Capper * !shared pmd case because we can allocate the pmd later as well, it makes the 6170c0d0381aSMike Kravetz * code much cleaner. 6171c0d0381aSMike Kravetz * 61720bf7b64eSMike Kravetz * This routine must be called with i_mmap_rwsem held in at least read mode if 61730bf7b64eSMike Kravetz * sharing is possible. For hugetlbfs, this prevents removal of any page 61740bf7b64eSMike Kravetz * table entries associated with the address space. This is important as we 61750bf7b64eSMike Kravetz * are setting up sharing based on existing page table entries (mappings). 61760bf7b64eSMike Kravetz * 61770bf7b64eSMike Kravetz * NOTE: This routine is only called from huge_pte_alloc. Some callers of 61780bf7b64eSMike Kravetz * huge_pte_alloc know that sharing is not possible and do not take 61790bf7b64eSMike Kravetz * i_mmap_rwsem as a performance optimization. This is handled by the 61800bf7b64eSMike Kravetz * if !vma_shareable check at the beginning of the routine. i_mmap_rwsem is 61810bf7b64eSMike Kravetz * only required for subsequent processing. 61823212b535SSteve Capper */ 6183aec44e0fSPeter Xu pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, 6184aec44e0fSPeter Xu unsigned long addr, pud_t *pud) 61853212b535SSteve Capper { 61863212b535SSteve Capper struct address_space *mapping = vma->vm_file->f_mapping; 61873212b535SSteve Capper pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + 61883212b535SSteve Capper vma->vm_pgoff; 61893212b535SSteve Capper struct vm_area_struct *svma; 61903212b535SSteve Capper unsigned long saddr; 61913212b535SSteve Capper pte_t *spte = NULL; 61923212b535SSteve Capper pte_t *pte; 6193cb900f41SKirill A. Shutemov spinlock_t *ptl; 61943212b535SSteve Capper 61950bf7b64eSMike Kravetz i_mmap_assert_locked(mapping); 61963212b535SSteve Capper vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { 61973212b535SSteve Capper if (svma == vma) 61983212b535SSteve Capper continue; 61993212b535SSteve Capper 62003212b535SSteve Capper saddr = page_table_shareable(svma, vma, addr, idx); 62013212b535SSteve Capper if (saddr) { 62027868a208SPunit Agrawal spte = huge_pte_offset(svma->vm_mm, saddr, 62037868a208SPunit Agrawal vma_mmu_pagesize(svma)); 62043212b535SSteve Capper if (spte) { 62053212b535SSteve Capper get_page(virt_to_page(spte)); 62063212b535SSteve Capper break; 62073212b535SSteve Capper } 62083212b535SSteve Capper } 62093212b535SSteve Capper } 62103212b535SSteve Capper 62113212b535SSteve Capper if (!spte) 62123212b535SSteve Capper goto out; 62133212b535SSteve Capper 62148bea8052SAneesh Kumar K.V ptl = huge_pte_lock(hstate_vma(vma), mm, spte); 6215dc6c9a35SKirill A. Shutemov if (pud_none(*pud)) { 62163212b535SSteve Capper pud_populate(mm, pud, 62173212b535SSteve Capper (pmd_t *)((unsigned long)spte & PAGE_MASK)); 6218c17b1f42SKirill A. Shutemov mm_inc_nr_pmds(mm); 6219dc6c9a35SKirill A. Shutemov } else { 62203212b535SSteve Capper put_page(virt_to_page(spte)); 6221dc6c9a35SKirill A. Shutemov } 6222cb900f41SKirill A. Shutemov spin_unlock(ptl); 62233212b535SSteve Capper out: 62243212b535SSteve Capper pte = (pte_t *)pmd_alloc(mm, pud, addr); 62253212b535SSteve Capper return pte; 62263212b535SSteve Capper } 62273212b535SSteve Capper 62283212b535SSteve Capper /* 62293212b535SSteve Capper * unmap huge page backed by shared pte. 62303212b535SSteve Capper * 62313212b535SSteve Capper * Hugetlb pte page is ref counted at the time of mapping. If pte is shared 62323212b535SSteve Capper * indicated by page_count > 1, unmap is achieved by clearing pud and 62333212b535SSteve Capper * decrementing the ref count. If count == 1, the pte page is not shared. 62343212b535SSteve Capper * 6235c0d0381aSMike Kravetz * Called with page table lock held and i_mmap_rwsem held in write mode. 62363212b535SSteve Capper * 62373212b535SSteve Capper * returns: 1 successfully unmapped a shared pte page 62383212b535SSteve Capper * 0 the underlying pte page is not shared, or it is the last user 62393212b535SSteve Capper */ 624034ae204fSMike Kravetz int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma, 624134ae204fSMike Kravetz unsigned long *addr, pte_t *ptep) 62423212b535SSteve Capper { 62433212b535SSteve Capper pgd_t *pgd = pgd_offset(mm, *addr); 6244c2febafcSKirill A. Shutemov p4d_t *p4d = p4d_offset(pgd, *addr); 6245c2febafcSKirill A. Shutemov pud_t *pud = pud_offset(p4d, *addr); 62463212b535SSteve Capper 624734ae204fSMike Kravetz i_mmap_assert_write_locked(vma->vm_file->f_mapping); 62483212b535SSteve Capper BUG_ON(page_count(virt_to_page(ptep)) == 0); 62493212b535SSteve Capper if (page_count(virt_to_page(ptep)) == 1) 62503212b535SSteve Capper return 0; 62513212b535SSteve Capper 62523212b535SSteve Capper pud_clear(pud); 62533212b535SSteve Capper put_page(virt_to_page(ptep)); 6254dc6c9a35SKirill A. Shutemov mm_dec_nr_pmds(mm); 62553212b535SSteve Capper *addr = ALIGN(*addr, HPAGE_SIZE * PTRS_PER_PTE) - HPAGE_SIZE; 62563212b535SSteve Capper return 1; 62573212b535SSteve Capper } 6258c1991e07SPeter Xu 62599e5fc74cSSteve Capper #else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ 6260aec44e0fSPeter Xu pte_t *huge_pmd_share(struct mm_struct *mm, struct vm_area_struct *vma, 6261aec44e0fSPeter Xu unsigned long addr, pud_t *pud) 62629e5fc74cSSteve Capper { 62639e5fc74cSSteve Capper return NULL; 62649e5fc74cSSteve Capper } 6265e81f2d22SZhang Zhen 626634ae204fSMike Kravetz int huge_pmd_unshare(struct mm_struct *mm, struct vm_area_struct *vma, 626734ae204fSMike Kravetz unsigned long *addr, pte_t *ptep) 6268e81f2d22SZhang Zhen { 6269e81f2d22SZhang Zhen return 0; 6270e81f2d22SZhang Zhen } 6271017b1660SMike Kravetz 6272017b1660SMike Kravetz void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, 6273017b1660SMike Kravetz unsigned long *start, unsigned long *end) 6274017b1660SMike Kravetz { 6275017b1660SMike Kravetz } 6276c1991e07SPeter Xu 6277c1991e07SPeter Xu bool want_pmd_share(struct vm_area_struct *vma, unsigned long addr) 6278c1991e07SPeter Xu { 6279c1991e07SPeter Xu return false; 6280c1991e07SPeter Xu } 62813212b535SSteve Capper #endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ 62823212b535SSteve Capper 62839e5fc74cSSteve Capper #ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB 6284aec44e0fSPeter Xu pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, 62859e5fc74cSSteve Capper unsigned long addr, unsigned long sz) 62869e5fc74cSSteve Capper { 62879e5fc74cSSteve Capper pgd_t *pgd; 6288c2febafcSKirill A. Shutemov p4d_t *p4d; 62899e5fc74cSSteve Capper pud_t *pud; 62909e5fc74cSSteve Capper pte_t *pte = NULL; 62919e5fc74cSSteve Capper 62929e5fc74cSSteve Capper pgd = pgd_offset(mm, addr); 6293f4f0a3d8SKirill A. Shutemov p4d = p4d_alloc(mm, pgd, addr); 6294f4f0a3d8SKirill A. Shutemov if (!p4d) 6295f4f0a3d8SKirill A. Shutemov return NULL; 6296c2febafcSKirill A. Shutemov pud = pud_alloc(mm, p4d, addr); 62979e5fc74cSSteve Capper if (pud) { 62989e5fc74cSSteve Capper if (sz == PUD_SIZE) { 62999e5fc74cSSteve Capper pte = (pte_t *)pud; 63009e5fc74cSSteve Capper } else { 63019e5fc74cSSteve Capper BUG_ON(sz != PMD_SIZE); 6302c1991e07SPeter Xu if (want_pmd_share(vma, addr) && pud_none(*pud)) 6303aec44e0fSPeter Xu pte = huge_pmd_share(mm, vma, addr, pud); 63049e5fc74cSSteve Capper else 63059e5fc74cSSteve Capper pte = (pte_t *)pmd_alloc(mm, pud, addr); 63069e5fc74cSSteve Capper } 63079e5fc74cSSteve Capper } 63084e666314SMichal Hocko BUG_ON(pte && pte_present(*pte) && !pte_huge(*pte)); 63099e5fc74cSSteve Capper 63109e5fc74cSSteve Capper return pte; 63119e5fc74cSSteve Capper } 63129e5fc74cSSteve Capper 63139b19df29SPunit Agrawal /* 63149b19df29SPunit Agrawal * huge_pte_offset() - Walk the page table to resolve the hugepage 63159b19df29SPunit Agrawal * entry at address @addr 63169b19df29SPunit Agrawal * 63178ac0b81aSLi Xinhai * Return: Pointer to page table entry (PUD or PMD) for 63188ac0b81aSLi Xinhai * address @addr, or NULL if a !p*d_present() entry is encountered and the 63199b19df29SPunit Agrawal * size @sz doesn't match the hugepage size at this level of the page 63209b19df29SPunit Agrawal * table. 63219b19df29SPunit Agrawal */ 63227868a208SPunit Agrawal pte_t *huge_pte_offset(struct mm_struct *mm, 63237868a208SPunit Agrawal unsigned long addr, unsigned long sz) 63249e5fc74cSSteve Capper { 63259e5fc74cSSteve Capper pgd_t *pgd; 6326c2febafcSKirill A. Shutemov p4d_t *p4d; 63278ac0b81aSLi Xinhai pud_t *pud; 63288ac0b81aSLi Xinhai pmd_t *pmd; 63299e5fc74cSSteve Capper 63309e5fc74cSSteve Capper pgd = pgd_offset(mm, addr); 6331c2febafcSKirill A. Shutemov if (!pgd_present(*pgd)) 6332c2febafcSKirill A. Shutemov return NULL; 6333c2febafcSKirill A. Shutemov p4d = p4d_offset(pgd, addr); 6334c2febafcSKirill A. Shutemov if (!p4d_present(*p4d)) 6335c2febafcSKirill A. Shutemov return NULL; 63369b19df29SPunit Agrawal 6337c2febafcSKirill A. Shutemov pud = pud_offset(p4d, addr); 63388ac0b81aSLi Xinhai if (sz == PUD_SIZE) 63398ac0b81aSLi Xinhai /* must be pud huge, non-present or none */ 63409e5fc74cSSteve Capper return (pte_t *)pud; 63418ac0b81aSLi Xinhai if (!pud_present(*pud)) 63428ac0b81aSLi Xinhai return NULL; 63438ac0b81aSLi Xinhai /* must have a valid entry and size to go further */ 63449b19df29SPunit Agrawal 63459e5fc74cSSteve Capper pmd = pmd_offset(pud, addr); 63468ac0b81aSLi Xinhai /* must be pmd huge, non-present or none */ 63479e5fc74cSSteve Capper return (pte_t *)pmd; 63489e5fc74cSSteve Capper } 63499e5fc74cSSteve Capper 635061f77edaSNaoya Horiguchi #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ 635161f77edaSNaoya Horiguchi 635261f77edaSNaoya Horiguchi /* 635361f77edaSNaoya Horiguchi * These functions are overwritable if your architecture needs its own 635461f77edaSNaoya Horiguchi * behavior. 635561f77edaSNaoya Horiguchi */ 635661f77edaSNaoya Horiguchi struct page * __weak 635761f77edaSNaoya Horiguchi follow_huge_addr(struct mm_struct *mm, unsigned long address, 635861f77edaSNaoya Horiguchi int write) 635961f77edaSNaoya Horiguchi { 636061f77edaSNaoya Horiguchi return ERR_PTR(-EINVAL); 636161f77edaSNaoya Horiguchi } 636261f77edaSNaoya Horiguchi 636361f77edaSNaoya Horiguchi struct page * __weak 63644dc71451SAneesh Kumar K.V follow_huge_pd(struct vm_area_struct *vma, 63654dc71451SAneesh Kumar K.V unsigned long address, hugepd_t hpd, int flags, int pdshift) 63664dc71451SAneesh Kumar K.V { 63674dc71451SAneesh Kumar K.V WARN(1, "hugepd follow called with no support for hugepage directory format\n"); 63684dc71451SAneesh Kumar K.V return NULL; 63694dc71451SAneesh Kumar K.V } 63704dc71451SAneesh Kumar K.V 63714dc71451SAneesh Kumar K.V struct page * __weak 63729e5fc74cSSteve Capper follow_huge_pmd(struct mm_struct *mm, unsigned long address, 6373e66f17ffSNaoya Horiguchi pmd_t *pmd, int flags) 63749e5fc74cSSteve Capper { 6375e66f17ffSNaoya Horiguchi struct page *page = NULL; 6376e66f17ffSNaoya Horiguchi spinlock_t *ptl; 6377c9d398faSNaoya Horiguchi pte_t pte; 63783faa52c0SJohn Hubbard 63793faa52c0SJohn Hubbard /* FOLL_GET and FOLL_PIN are mutually exclusive. */ 63803faa52c0SJohn Hubbard if (WARN_ON_ONCE((flags & (FOLL_PIN | FOLL_GET)) == 63813faa52c0SJohn Hubbard (FOLL_PIN | FOLL_GET))) 63823faa52c0SJohn Hubbard return NULL; 63833faa52c0SJohn Hubbard 6384e66f17ffSNaoya Horiguchi retry: 6385e66f17ffSNaoya Horiguchi ptl = pmd_lockptr(mm, pmd); 6386e66f17ffSNaoya Horiguchi spin_lock(ptl); 6387e66f17ffSNaoya Horiguchi /* 6388e66f17ffSNaoya Horiguchi * make sure that the address range covered by this pmd is not 6389e66f17ffSNaoya Horiguchi * unmapped from other threads. 6390e66f17ffSNaoya Horiguchi */ 6391e66f17ffSNaoya Horiguchi if (!pmd_huge(*pmd)) 6392e66f17ffSNaoya Horiguchi goto out; 6393c9d398faSNaoya Horiguchi pte = huge_ptep_get((pte_t *)pmd); 6394c9d398faSNaoya Horiguchi if (pte_present(pte)) { 639597534127SGerald Schaefer page = pmd_page(*pmd) + ((address & ~PMD_MASK) >> PAGE_SHIFT); 63963faa52c0SJohn Hubbard /* 63973faa52c0SJohn Hubbard * try_grab_page() should always succeed here, because: a) we 63983faa52c0SJohn Hubbard * hold the pmd (ptl) lock, and b) we've just checked that the 63993faa52c0SJohn Hubbard * huge pmd (head) page is present in the page tables. The ptl 64003faa52c0SJohn Hubbard * prevents the head page and tail pages from being rearranged 64013faa52c0SJohn Hubbard * in any way. So this page must be available at this point, 64023faa52c0SJohn Hubbard * unless the page refcount overflowed: 64033faa52c0SJohn Hubbard */ 64043faa52c0SJohn Hubbard if (WARN_ON_ONCE(!try_grab_page(page, flags))) { 64053faa52c0SJohn Hubbard page = NULL; 64063faa52c0SJohn Hubbard goto out; 64073faa52c0SJohn Hubbard } 6408e66f17ffSNaoya Horiguchi } else { 6409c9d398faSNaoya Horiguchi if (is_hugetlb_entry_migration(pte)) { 6410e66f17ffSNaoya Horiguchi spin_unlock(ptl); 6411e66f17ffSNaoya Horiguchi __migration_entry_wait(mm, (pte_t *)pmd, ptl); 6412e66f17ffSNaoya Horiguchi goto retry; 6413e66f17ffSNaoya Horiguchi } 6414e66f17ffSNaoya Horiguchi /* 6415e66f17ffSNaoya Horiguchi * hwpoisoned entry is treated as no_page_table in 6416e66f17ffSNaoya Horiguchi * follow_page_mask(). 6417e66f17ffSNaoya Horiguchi */ 6418e66f17ffSNaoya Horiguchi } 6419e66f17ffSNaoya Horiguchi out: 6420e66f17ffSNaoya Horiguchi spin_unlock(ptl); 64219e5fc74cSSteve Capper return page; 64229e5fc74cSSteve Capper } 64239e5fc74cSSteve Capper 642461f77edaSNaoya Horiguchi struct page * __weak 64259e5fc74cSSteve Capper follow_huge_pud(struct mm_struct *mm, unsigned long address, 6426e66f17ffSNaoya Horiguchi pud_t *pud, int flags) 64279e5fc74cSSteve Capper { 64283faa52c0SJohn Hubbard if (flags & (FOLL_GET | FOLL_PIN)) 6429e66f17ffSNaoya Horiguchi return NULL; 64309e5fc74cSSteve Capper 6431e66f17ffSNaoya Horiguchi return pte_page(*(pte_t *)pud) + ((address & ~PUD_MASK) >> PAGE_SHIFT); 64329e5fc74cSSteve Capper } 64339e5fc74cSSteve Capper 6434faaa5b62SAnshuman Khandual struct page * __weak 6435faaa5b62SAnshuman Khandual follow_huge_pgd(struct mm_struct *mm, unsigned long address, pgd_t *pgd, int flags) 6436faaa5b62SAnshuman Khandual { 64373faa52c0SJohn Hubbard if (flags & (FOLL_GET | FOLL_PIN)) 6438faaa5b62SAnshuman Khandual return NULL; 6439faaa5b62SAnshuman Khandual 6440faaa5b62SAnshuman Khandual return pte_page(*(pte_t *)pgd) + ((address & ~PGDIR_MASK) >> PAGE_SHIFT); 6441faaa5b62SAnshuman Khandual } 6442faaa5b62SAnshuman Khandual 644331caf665SNaoya Horiguchi bool isolate_huge_page(struct page *page, struct list_head *list) 644431caf665SNaoya Horiguchi { 6445bcc54222SNaoya Horiguchi bool ret = true; 6446bcc54222SNaoya Horiguchi 6447db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 64488f251a3dSMike Kravetz if (!PageHeadHuge(page) || 64498f251a3dSMike Kravetz !HPageMigratable(page) || 64500eb2df2bSMuchun Song !get_page_unless_zero(page)) { 6451bcc54222SNaoya Horiguchi ret = false; 6452bcc54222SNaoya Horiguchi goto unlock; 6453bcc54222SNaoya Horiguchi } 64548f251a3dSMike Kravetz ClearHPageMigratable(page); 645531caf665SNaoya Horiguchi list_move_tail(&page->lru, list); 6456bcc54222SNaoya Horiguchi unlock: 6457db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 6458bcc54222SNaoya Horiguchi return ret; 645931caf665SNaoya Horiguchi } 646031caf665SNaoya Horiguchi 646125182f05SNaoya Horiguchi int get_hwpoison_huge_page(struct page *page, bool *hugetlb) 646225182f05SNaoya Horiguchi { 646325182f05SNaoya Horiguchi int ret = 0; 646425182f05SNaoya Horiguchi 646525182f05SNaoya Horiguchi *hugetlb = false; 646625182f05SNaoya Horiguchi spin_lock_irq(&hugetlb_lock); 646725182f05SNaoya Horiguchi if (PageHeadHuge(page)) { 646825182f05SNaoya Horiguchi *hugetlb = true; 646925182f05SNaoya Horiguchi if (HPageFreed(page) || HPageMigratable(page)) 647025182f05SNaoya Horiguchi ret = get_page_unless_zero(page); 64710ed950d1SNaoya Horiguchi else 64720ed950d1SNaoya Horiguchi ret = -EBUSY; 647325182f05SNaoya Horiguchi } 647425182f05SNaoya Horiguchi spin_unlock_irq(&hugetlb_lock); 647525182f05SNaoya Horiguchi return ret; 647625182f05SNaoya Horiguchi } 647725182f05SNaoya Horiguchi 647831caf665SNaoya Horiguchi void putback_active_hugepage(struct page *page) 647931caf665SNaoya Horiguchi { 6480db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 64818f251a3dSMike Kravetz SetHPageMigratable(page); 648231caf665SNaoya Horiguchi list_move_tail(&page->lru, &(page_hstate(page))->hugepage_activelist); 6483db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 648431caf665SNaoya Horiguchi put_page(page); 648531caf665SNaoya Horiguchi } 6486ab5ac90aSMichal Hocko 6487ab5ac90aSMichal Hocko void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason) 6488ab5ac90aSMichal Hocko { 6489ab5ac90aSMichal Hocko struct hstate *h = page_hstate(oldpage); 6490ab5ac90aSMichal Hocko 6491ab5ac90aSMichal Hocko hugetlb_cgroup_migrate(oldpage, newpage); 6492ab5ac90aSMichal Hocko set_page_owner_migrate_reason(newpage, reason); 6493ab5ac90aSMichal Hocko 6494ab5ac90aSMichal Hocko /* 6495ab5ac90aSMichal Hocko * transfer temporary state of the new huge page. This is 6496ab5ac90aSMichal Hocko * reverse to other transitions because the newpage is going to 6497ab5ac90aSMichal Hocko * be final while the old one will be freed so it takes over 6498ab5ac90aSMichal Hocko * the temporary status. 6499ab5ac90aSMichal Hocko * 6500ab5ac90aSMichal Hocko * Also note that we have to transfer the per-node surplus state 6501ab5ac90aSMichal Hocko * here as well otherwise the global surplus count will not match 6502ab5ac90aSMichal Hocko * the per-node's. 6503ab5ac90aSMichal Hocko */ 65049157c311SMike Kravetz if (HPageTemporary(newpage)) { 6505ab5ac90aSMichal Hocko int old_nid = page_to_nid(oldpage); 6506ab5ac90aSMichal Hocko int new_nid = page_to_nid(newpage); 6507ab5ac90aSMichal Hocko 65089157c311SMike Kravetz SetHPageTemporary(oldpage); 65099157c311SMike Kravetz ClearHPageTemporary(newpage); 6510ab5ac90aSMichal Hocko 65115af1ab1dSMiaohe Lin /* 65125af1ab1dSMiaohe Lin * There is no need to transfer the per-node surplus state 65135af1ab1dSMiaohe Lin * when we do not cross the node. 65145af1ab1dSMiaohe Lin */ 65155af1ab1dSMiaohe Lin if (new_nid == old_nid) 65165af1ab1dSMiaohe Lin return; 6517db71ef79SMike Kravetz spin_lock_irq(&hugetlb_lock); 6518ab5ac90aSMichal Hocko if (h->surplus_huge_pages_node[old_nid]) { 6519ab5ac90aSMichal Hocko h->surplus_huge_pages_node[old_nid]--; 6520ab5ac90aSMichal Hocko h->surplus_huge_pages_node[new_nid]++; 6521ab5ac90aSMichal Hocko } 6522db71ef79SMike Kravetz spin_unlock_irq(&hugetlb_lock); 6523ab5ac90aSMichal Hocko } 6524ab5ac90aSMichal Hocko } 6525cf11e85fSRoman Gushchin 65266dfeaff9SPeter Xu /* 65276dfeaff9SPeter Xu * This function will unconditionally remove all the shared pmd pgtable entries 65286dfeaff9SPeter Xu * within the specific vma for a hugetlbfs memory range. 65296dfeaff9SPeter Xu */ 65306dfeaff9SPeter Xu void hugetlb_unshare_all_pmds(struct vm_area_struct *vma) 65316dfeaff9SPeter Xu { 65326dfeaff9SPeter Xu struct hstate *h = hstate_vma(vma); 65336dfeaff9SPeter Xu unsigned long sz = huge_page_size(h); 65346dfeaff9SPeter Xu struct mm_struct *mm = vma->vm_mm; 65356dfeaff9SPeter Xu struct mmu_notifier_range range; 65366dfeaff9SPeter Xu unsigned long address, start, end; 65376dfeaff9SPeter Xu spinlock_t *ptl; 65386dfeaff9SPeter Xu pte_t *ptep; 65396dfeaff9SPeter Xu 65406dfeaff9SPeter Xu if (!(vma->vm_flags & VM_MAYSHARE)) 65416dfeaff9SPeter Xu return; 65426dfeaff9SPeter Xu 65436dfeaff9SPeter Xu start = ALIGN(vma->vm_start, PUD_SIZE); 65446dfeaff9SPeter Xu end = ALIGN_DOWN(vma->vm_end, PUD_SIZE); 65456dfeaff9SPeter Xu 65466dfeaff9SPeter Xu if (start >= end) 65476dfeaff9SPeter Xu return; 65486dfeaff9SPeter Xu 65496dfeaff9SPeter Xu /* 65506dfeaff9SPeter Xu * No need to call adjust_range_if_pmd_sharing_possible(), because 65516dfeaff9SPeter Xu * we have already done the PUD_SIZE alignment. 65526dfeaff9SPeter Xu */ 65536dfeaff9SPeter Xu mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, mm, 65546dfeaff9SPeter Xu start, end); 65556dfeaff9SPeter Xu mmu_notifier_invalidate_range_start(&range); 65566dfeaff9SPeter Xu i_mmap_lock_write(vma->vm_file->f_mapping); 65576dfeaff9SPeter Xu for (address = start; address < end; address += PUD_SIZE) { 65586dfeaff9SPeter Xu unsigned long tmp = address; 65596dfeaff9SPeter Xu 65606dfeaff9SPeter Xu ptep = huge_pte_offset(mm, address, sz); 65616dfeaff9SPeter Xu if (!ptep) 65626dfeaff9SPeter Xu continue; 65636dfeaff9SPeter Xu ptl = huge_pte_lock(h, mm, ptep); 65646dfeaff9SPeter Xu /* We don't want 'address' to be changed */ 65656dfeaff9SPeter Xu huge_pmd_unshare(mm, vma, &tmp, ptep); 65666dfeaff9SPeter Xu spin_unlock(ptl); 65676dfeaff9SPeter Xu } 65686dfeaff9SPeter Xu flush_hugetlb_tlb_range(vma, start, end); 65696dfeaff9SPeter Xu i_mmap_unlock_write(vma->vm_file->f_mapping); 65706dfeaff9SPeter Xu /* 65716dfeaff9SPeter Xu * No need to call mmu_notifier_invalidate_range(), see 65726dfeaff9SPeter Xu * Documentation/vm/mmu_notifier.rst. 65736dfeaff9SPeter Xu */ 65746dfeaff9SPeter Xu mmu_notifier_invalidate_range_end(&range); 65756dfeaff9SPeter Xu } 65766dfeaff9SPeter Xu 6577cf11e85fSRoman Gushchin #ifdef CONFIG_CMA 6578cf11e85fSRoman Gushchin static bool cma_reserve_called __initdata; 6579cf11e85fSRoman Gushchin 6580cf11e85fSRoman Gushchin static int __init cmdline_parse_hugetlb_cma(char *p) 6581cf11e85fSRoman Gushchin { 6582cf11e85fSRoman Gushchin hugetlb_cma_size = memparse(p, &p); 6583cf11e85fSRoman Gushchin return 0; 6584cf11e85fSRoman Gushchin } 6585cf11e85fSRoman Gushchin 6586cf11e85fSRoman Gushchin early_param("hugetlb_cma", cmdline_parse_hugetlb_cma); 6587cf11e85fSRoman Gushchin 6588cf11e85fSRoman Gushchin void __init hugetlb_cma_reserve(int order) 6589cf11e85fSRoman Gushchin { 6590cf11e85fSRoman Gushchin unsigned long size, reserved, per_node; 6591cf11e85fSRoman Gushchin int nid; 6592cf11e85fSRoman Gushchin 6593cf11e85fSRoman Gushchin cma_reserve_called = true; 6594cf11e85fSRoman Gushchin 6595cf11e85fSRoman Gushchin if (!hugetlb_cma_size) 6596cf11e85fSRoman Gushchin return; 6597cf11e85fSRoman Gushchin 6598cf11e85fSRoman Gushchin if (hugetlb_cma_size < (PAGE_SIZE << order)) { 6599cf11e85fSRoman Gushchin pr_warn("hugetlb_cma: cma area should be at least %lu MiB\n", 6600cf11e85fSRoman Gushchin (PAGE_SIZE << order) / SZ_1M); 6601a01f4390SMike Kravetz hugetlb_cma_size = 0; 6602cf11e85fSRoman Gushchin return; 6603cf11e85fSRoman Gushchin } 6604cf11e85fSRoman Gushchin 6605cf11e85fSRoman Gushchin /* 6606cf11e85fSRoman Gushchin * If 3 GB area is requested on a machine with 4 numa nodes, 6607cf11e85fSRoman Gushchin * let's allocate 1 GB on first three nodes and ignore the last one. 6608cf11e85fSRoman Gushchin */ 6609cf11e85fSRoman Gushchin per_node = DIV_ROUND_UP(hugetlb_cma_size, nr_online_nodes); 6610cf11e85fSRoman Gushchin pr_info("hugetlb_cma: reserve %lu MiB, up to %lu MiB per node\n", 6611cf11e85fSRoman Gushchin hugetlb_cma_size / SZ_1M, per_node / SZ_1M); 6612cf11e85fSRoman Gushchin 6613cf11e85fSRoman Gushchin reserved = 0; 6614cf11e85fSRoman Gushchin for_each_node_state(nid, N_ONLINE) { 6615cf11e85fSRoman Gushchin int res; 66162281f797SBarry Song char name[CMA_MAX_NAME]; 6617cf11e85fSRoman Gushchin 6618cf11e85fSRoman Gushchin size = min(per_node, hugetlb_cma_size - reserved); 6619cf11e85fSRoman Gushchin size = round_up(size, PAGE_SIZE << order); 6620cf11e85fSRoman Gushchin 66212281f797SBarry Song snprintf(name, sizeof(name), "hugetlb%d", nid); 6622a01f4390SMike Kravetz /* 6623a01f4390SMike Kravetz * Note that 'order per bit' is based on smallest size that 6624a01f4390SMike Kravetz * may be returned to CMA allocator in the case of 6625a01f4390SMike Kravetz * huge page demotion. 6626a01f4390SMike Kravetz */ 6627a01f4390SMike Kravetz res = cma_declare_contiguous_nid(0, size, 0, 6628a01f4390SMike Kravetz PAGE_SIZE << HUGETLB_PAGE_ORDER, 662929d0f41dSBarry Song 0, false, name, 6630cf11e85fSRoman Gushchin &hugetlb_cma[nid], nid); 6631cf11e85fSRoman Gushchin if (res) { 6632cf11e85fSRoman Gushchin pr_warn("hugetlb_cma: reservation failed: err %d, node %d", 6633cf11e85fSRoman Gushchin res, nid); 6634cf11e85fSRoman Gushchin continue; 6635cf11e85fSRoman Gushchin } 6636cf11e85fSRoman Gushchin 6637cf11e85fSRoman Gushchin reserved += size; 6638cf11e85fSRoman Gushchin pr_info("hugetlb_cma: reserved %lu MiB on node %d\n", 6639cf11e85fSRoman Gushchin size / SZ_1M, nid); 6640cf11e85fSRoman Gushchin 6641cf11e85fSRoman Gushchin if (reserved >= hugetlb_cma_size) 6642cf11e85fSRoman Gushchin break; 6643cf11e85fSRoman Gushchin } 6644a01f4390SMike Kravetz 6645a01f4390SMike Kravetz if (!reserved) 6646a01f4390SMike Kravetz /* 6647a01f4390SMike Kravetz * hugetlb_cma_size is used to determine if allocations from 6648a01f4390SMike Kravetz * cma are possible. Set to zero if no cma regions are set up. 6649a01f4390SMike Kravetz */ 6650a01f4390SMike Kravetz hugetlb_cma_size = 0; 6651cf11e85fSRoman Gushchin } 6652cf11e85fSRoman Gushchin 6653cf11e85fSRoman Gushchin void __init hugetlb_cma_check(void) 6654cf11e85fSRoman Gushchin { 6655cf11e85fSRoman Gushchin if (!hugetlb_cma_size || cma_reserve_called) 6656cf11e85fSRoman Gushchin return; 6657cf11e85fSRoman Gushchin 6658cf11e85fSRoman Gushchin pr_warn("hugetlb_cma: the option isn't supported by current arch\n"); 6659cf11e85fSRoman Gushchin } 6660cf11e85fSRoman Gushchin 6661cf11e85fSRoman Gushchin #endif /* CONFIG_CMA */ 6662