11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * Generic hugetlb support. 36d49e352SNadia Yvette Chambers * (C) Nadia Yvette Chambers, April 2004 41da177e4SLinus Torvalds */ 51da177e4SLinus Torvalds #include <linux/list.h> 61da177e4SLinus Torvalds #include <linux/init.h> 71da177e4SLinus Torvalds #include <linux/module.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> 19aa888a74SAndi Kleen #include <linux/bootmem.h> 20a3437870SNishanth Aravamudan #include <linux/sysfs.h> 215a0e3ad6STejun Heo #include <linux/slab.h> 220fe6e20bSNaoya Horiguchi #include <linux/rmap.h> 23fd6a03edSNaoya Horiguchi #include <linux/swap.h> 24fd6a03edSNaoya Horiguchi #include <linux/swapops.h> 25c8721bbbSNaoya Horiguchi #include <linux/page-isolation.h> 268382d914SDavidlohr Bueso #include <linux/jhash.h> 27d6606683SLinus Torvalds 2863551ae0SDavid Gibson #include <asm/page.h> 2963551ae0SDavid Gibson #include <asm/pgtable.h> 3024669e58SAneesh Kumar K.V #include <asm/tlb.h> 3163551ae0SDavid Gibson 3224669e58SAneesh Kumar K.V #include <linux/io.h> 3363551ae0SDavid Gibson #include <linux/hugetlb.h> 349dd540e2SAneesh Kumar K.V #include <linux/hugetlb_cgroup.h> 359a305230SLee Schermerhorn #include <linux/node.h> 367835e98bSNick Piggin #include "internal.h" 371da177e4SLinus Torvalds 38753162cdSAndrey Ryabinin int hugepages_treat_as_movable; 39a5516438SAndi Kleen 40c3f38a38SAneesh Kumar K.V int hugetlb_max_hstate __read_mostly; 41e5ff2159SAndi Kleen unsigned int default_hstate_idx; 42e5ff2159SAndi Kleen struct hstate hstates[HUGE_MAX_HSTATE]; 43641844f5SNaoya Horiguchi /* 44641844f5SNaoya Horiguchi * Minimum page order among possible hugepage sizes, set to a proper value 45641844f5SNaoya Horiguchi * at boot time. 46641844f5SNaoya Horiguchi */ 47641844f5SNaoya Horiguchi static unsigned int minimum_order __read_mostly = UINT_MAX; 48e5ff2159SAndi Kleen 4953ba51d2SJon Tollefson __initdata LIST_HEAD(huge_boot_pages); 5053ba51d2SJon Tollefson 51e5ff2159SAndi Kleen /* for command line parsing */ 52e5ff2159SAndi Kleen static struct hstate * __initdata parsed_hstate; 53e5ff2159SAndi Kleen static unsigned long __initdata default_hstate_max_huge_pages; 54e11bfbfcSNick Piggin static unsigned long __initdata default_hstate_size; 55e5ff2159SAndi Kleen 563935baa9SDavid Gibson /* 5731caf665SNaoya Horiguchi * Protects updates to hugepage_freelists, hugepage_activelist, nr_huge_pages, 5831caf665SNaoya Horiguchi * free_huge_pages, and surplus_huge_pages. 593935baa9SDavid Gibson */ 60c3f38a38SAneesh Kumar K.V DEFINE_SPINLOCK(hugetlb_lock); 610bd0f9fbSEric Paris 628382d914SDavidlohr Bueso /* 638382d914SDavidlohr Bueso * Serializes faults on the same logical page. This is used to 648382d914SDavidlohr Bueso * prevent spurious OOMs when the hugepage pool is fully utilized. 658382d914SDavidlohr Bueso */ 668382d914SDavidlohr Bueso static int num_fault_mutexes; 67c672c7f2SMike Kravetz struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp; 688382d914SDavidlohr Bueso 697ca02d0aSMike Kravetz /* Forward declaration */ 707ca02d0aSMike Kravetz static int hugetlb_acct_memory(struct hstate *h, long delta); 717ca02d0aSMike Kravetz 7290481622SDavid Gibson static inline void unlock_or_release_subpool(struct hugepage_subpool *spool) 7390481622SDavid Gibson { 7490481622SDavid Gibson bool free = (spool->count == 0) && (spool->used_hpages == 0); 7590481622SDavid Gibson 7690481622SDavid Gibson spin_unlock(&spool->lock); 7790481622SDavid Gibson 7890481622SDavid Gibson /* If no pages are used, and no other handles to the subpool 797ca02d0aSMike Kravetz * remain, give up any reservations mased on minimum size and 807ca02d0aSMike Kravetz * free the subpool */ 817ca02d0aSMike Kravetz if (free) { 827ca02d0aSMike Kravetz if (spool->min_hpages != -1) 837ca02d0aSMike Kravetz hugetlb_acct_memory(spool->hstate, 847ca02d0aSMike Kravetz -spool->min_hpages); 8590481622SDavid Gibson kfree(spool); 8690481622SDavid Gibson } 877ca02d0aSMike Kravetz } 8890481622SDavid Gibson 897ca02d0aSMike Kravetz struct hugepage_subpool *hugepage_new_subpool(struct hstate *h, long max_hpages, 907ca02d0aSMike Kravetz long min_hpages) 9190481622SDavid Gibson { 9290481622SDavid Gibson struct hugepage_subpool *spool; 9390481622SDavid Gibson 94c6a91820SMike Kravetz spool = kzalloc(sizeof(*spool), GFP_KERNEL); 9590481622SDavid Gibson if (!spool) 9690481622SDavid Gibson return NULL; 9790481622SDavid Gibson 9890481622SDavid Gibson spin_lock_init(&spool->lock); 9990481622SDavid Gibson spool->count = 1; 1007ca02d0aSMike Kravetz spool->max_hpages = max_hpages; 1017ca02d0aSMike Kravetz spool->hstate = h; 1027ca02d0aSMike Kravetz spool->min_hpages = min_hpages; 1037ca02d0aSMike Kravetz 1047ca02d0aSMike Kravetz if (min_hpages != -1 && hugetlb_acct_memory(h, min_hpages)) { 1057ca02d0aSMike Kravetz kfree(spool); 1067ca02d0aSMike Kravetz return NULL; 1077ca02d0aSMike Kravetz } 1087ca02d0aSMike Kravetz spool->rsv_hpages = min_hpages; 10990481622SDavid Gibson 11090481622SDavid Gibson return spool; 11190481622SDavid Gibson } 11290481622SDavid Gibson 11390481622SDavid Gibson void hugepage_put_subpool(struct hugepage_subpool *spool) 11490481622SDavid Gibson { 11590481622SDavid Gibson spin_lock(&spool->lock); 11690481622SDavid Gibson BUG_ON(!spool->count); 11790481622SDavid Gibson spool->count--; 11890481622SDavid Gibson unlock_or_release_subpool(spool); 11990481622SDavid Gibson } 12090481622SDavid Gibson 1211c5ecae3SMike Kravetz /* 1221c5ecae3SMike Kravetz * Subpool accounting for allocating and reserving pages. 1231c5ecae3SMike Kravetz * Return -ENOMEM if there are not enough resources to satisfy the 1241c5ecae3SMike Kravetz * the request. Otherwise, return the number of pages by which the 1251c5ecae3SMike Kravetz * global pools must be adjusted (upward). The returned value may 1261c5ecae3SMike Kravetz * only be different than the passed value (delta) in the case where 1271c5ecae3SMike Kravetz * a subpool minimum size must be manitained. 1281c5ecae3SMike Kravetz */ 1291c5ecae3SMike Kravetz static long hugepage_subpool_get_pages(struct hugepage_subpool *spool, 13090481622SDavid Gibson long delta) 13190481622SDavid Gibson { 1321c5ecae3SMike Kravetz long ret = delta; 13390481622SDavid Gibson 13490481622SDavid Gibson if (!spool) 1351c5ecae3SMike Kravetz return ret; 13690481622SDavid Gibson 13790481622SDavid Gibson spin_lock(&spool->lock); 13890481622SDavid Gibson 1391c5ecae3SMike Kravetz if (spool->max_hpages != -1) { /* maximum size accounting */ 1401c5ecae3SMike Kravetz if ((spool->used_hpages + delta) <= spool->max_hpages) 1411c5ecae3SMike Kravetz spool->used_hpages += delta; 1421c5ecae3SMike Kravetz else { 1431c5ecae3SMike Kravetz ret = -ENOMEM; 1441c5ecae3SMike Kravetz goto unlock_ret; 1451c5ecae3SMike Kravetz } 1461c5ecae3SMike Kravetz } 1471c5ecae3SMike Kravetz 1481c5ecae3SMike Kravetz if (spool->min_hpages != -1) { /* minimum size accounting */ 1491c5ecae3SMike Kravetz if (delta > spool->rsv_hpages) { 1501c5ecae3SMike Kravetz /* 1511c5ecae3SMike Kravetz * Asking for more reserves than those already taken on 1521c5ecae3SMike Kravetz * behalf of subpool. Return difference. 1531c5ecae3SMike Kravetz */ 1541c5ecae3SMike Kravetz ret = delta - spool->rsv_hpages; 1551c5ecae3SMike Kravetz spool->rsv_hpages = 0; 1561c5ecae3SMike Kravetz } else { 1571c5ecae3SMike Kravetz ret = 0; /* reserves already accounted for */ 1581c5ecae3SMike Kravetz spool->rsv_hpages -= delta; 1591c5ecae3SMike Kravetz } 1601c5ecae3SMike Kravetz } 1611c5ecae3SMike Kravetz 1621c5ecae3SMike Kravetz unlock_ret: 1631c5ecae3SMike Kravetz spin_unlock(&spool->lock); 16490481622SDavid Gibson return ret; 16590481622SDavid Gibson } 16690481622SDavid Gibson 1671c5ecae3SMike Kravetz /* 1681c5ecae3SMike Kravetz * Subpool accounting for freeing and unreserving pages. 1691c5ecae3SMike Kravetz * Return the number of global page reservations that must be dropped. 1701c5ecae3SMike Kravetz * The return value may only be different than the passed value (delta) 1711c5ecae3SMike Kravetz * in the case where a subpool minimum size must be maintained. 1721c5ecae3SMike Kravetz */ 1731c5ecae3SMike Kravetz static long hugepage_subpool_put_pages(struct hugepage_subpool *spool, 17490481622SDavid Gibson long delta) 17590481622SDavid Gibson { 1761c5ecae3SMike Kravetz long ret = delta; 1771c5ecae3SMike Kravetz 17890481622SDavid Gibson if (!spool) 1791c5ecae3SMike Kravetz return delta; 18090481622SDavid Gibson 18190481622SDavid Gibson spin_lock(&spool->lock); 1821c5ecae3SMike Kravetz 1831c5ecae3SMike Kravetz if (spool->max_hpages != -1) /* maximum size accounting */ 18490481622SDavid Gibson spool->used_hpages -= delta; 1851c5ecae3SMike Kravetz 1861c5ecae3SMike Kravetz if (spool->min_hpages != -1) { /* minimum size accounting */ 1871c5ecae3SMike Kravetz if (spool->rsv_hpages + delta <= spool->min_hpages) 1881c5ecae3SMike Kravetz ret = 0; 1891c5ecae3SMike Kravetz else 1901c5ecae3SMike Kravetz ret = spool->rsv_hpages + delta - spool->min_hpages; 1911c5ecae3SMike Kravetz 1921c5ecae3SMike Kravetz spool->rsv_hpages += delta; 1931c5ecae3SMike Kravetz if (spool->rsv_hpages > spool->min_hpages) 1941c5ecae3SMike Kravetz spool->rsv_hpages = spool->min_hpages; 1951c5ecae3SMike Kravetz } 1961c5ecae3SMike Kravetz 1971c5ecae3SMike Kravetz /* 1981c5ecae3SMike Kravetz * If hugetlbfs_put_super couldn't free spool due to an outstanding 1991c5ecae3SMike Kravetz * quota reference, free it now. 2001c5ecae3SMike Kravetz */ 20190481622SDavid Gibson unlock_or_release_subpool(spool); 2021c5ecae3SMike Kravetz 2031c5ecae3SMike Kravetz return ret; 20490481622SDavid Gibson } 20590481622SDavid Gibson 20690481622SDavid Gibson static inline struct hugepage_subpool *subpool_inode(struct inode *inode) 20790481622SDavid Gibson { 20890481622SDavid Gibson return HUGETLBFS_SB(inode->i_sb)->spool; 20990481622SDavid Gibson } 21090481622SDavid Gibson 21190481622SDavid Gibson static inline struct hugepage_subpool *subpool_vma(struct vm_area_struct *vma) 21290481622SDavid Gibson { 213496ad9aaSAl Viro return subpool_inode(file_inode(vma->vm_file)); 21490481622SDavid Gibson } 21590481622SDavid Gibson 216e7c4b0bfSAndy Whitcroft /* 21796822904SAndy Whitcroft * Region tracking -- allows tracking of reservations and instantiated pages 21896822904SAndy Whitcroft * across the pages in a mapping. 21984afd99bSAndy Whitcroft * 2201dd308a7SMike Kravetz * The region data structures are embedded into a resv_map and protected 2211dd308a7SMike Kravetz * by a resv_map's lock. The set of regions within the resv_map represent 2221dd308a7SMike Kravetz * reservations for huge pages, or huge pages that have already been 2231dd308a7SMike Kravetz * instantiated within the map. The from and to elements are huge page 2241dd308a7SMike Kravetz * indicies into the associated mapping. from indicates the starting index 2251dd308a7SMike Kravetz * of the region. to represents the first index past the end of the region. 2261dd308a7SMike Kravetz * 2271dd308a7SMike Kravetz * For example, a file region structure with from == 0 and to == 4 represents 2281dd308a7SMike Kravetz * four huge pages in a mapping. It is important to note that the to element 2291dd308a7SMike Kravetz * represents the first element past the end of the region. This is used in 2301dd308a7SMike Kravetz * arithmetic as 4(to) - 0(from) = 4 huge pages in the region. 2311dd308a7SMike Kravetz * 2321dd308a7SMike Kravetz * Interval notation of the form [from, to) will be used to indicate that 2331dd308a7SMike Kravetz * the endpoint from is inclusive and to is exclusive. 23496822904SAndy Whitcroft */ 23596822904SAndy Whitcroft struct file_region { 23696822904SAndy Whitcroft struct list_head link; 23796822904SAndy Whitcroft long from; 23896822904SAndy Whitcroft long to; 23996822904SAndy Whitcroft }; 24096822904SAndy Whitcroft 2411dd308a7SMike Kravetz /* 2421dd308a7SMike Kravetz * Add the huge page range represented by [f, t) to the reserve 2435e911373SMike Kravetz * map. In the normal case, existing regions will be expanded 2445e911373SMike Kravetz * to accommodate the specified range. Sufficient regions should 2455e911373SMike Kravetz * exist for expansion due to the previous call to region_chg 2465e911373SMike Kravetz * with the same range. However, it is possible that region_del 2475e911373SMike Kravetz * could have been called after region_chg and modifed the map 2485e911373SMike Kravetz * in such a way that no region exists to be expanded. In this 2495e911373SMike Kravetz * case, pull a region descriptor from the cache associated with 2505e911373SMike Kravetz * the map and use that for the new range. 251cf3ad20bSMike Kravetz * 252cf3ad20bSMike Kravetz * Return the number of new huge pages added to the map. This 253cf3ad20bSMike Kravetz * number is greater than or equal to zero. 2541dd308a7SMike Kravetz */ 2551406ec9bSJoonsoo Kim static long region_add(struct resv_map *resv, long f, long t) 25696822904SAndy Whitcroft { 2571406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 25896822904SAndy Whitcroft struct file_region *rg, *nrg, *trg; 259cf3ad20bSMike Kravetz long add = 0; 26096822904SAndy Whitcroft 2617b24d861SDavidlohr Bueso spin_lock(&resv->lock); 26296822904SAndy Whitcroft /* Locate the region we are either in or before. */ 26396822904SAndy Whitcroft list_for_each_entry(rg, head, link) 26496822904SAndy Whitcroft if (f <= rg->to) 26596822904SAndy Whitcroft break; 26696822904SAndy Whitcroft 2675e911373SMike Kravetz /* 2685e911373SMike Kravetz * If no region exists which can be expanded to include the 2695e911373SMike Kravetz * specified range, the list must have been modified by an 2705e911373SMike Kravetz * interleving call to region_del(). Pull a region descriptor 2715e911373SMike Kravetz * from the cache and use it for this range. 2725e911373SMike Kravetz */ 2735e911373SMike Kravetz if (&rg->link == head || t < rg->from) { 2745e911373SMike Kravetz VM_BUG_ON(resv->region_cache_count <= 0); 2755e911373SMike Kravetz 2765e911373SMike Kravetz resv->region_cache_count--; 2775e911373SMike Kravetz nrg = list_first_entry(&resv->region_cache, struct file_region, 2785e911373SMike Kravetz link); 2795e911373SMike Kravetz list_del(&nrg->link); 2805e911373SMike Kravetz 2815e911373SMike Kravetz nrg->from = f; 2825e911373SMike Kravetz nrg->to = t; 2835e911373SMike Kravetz list_add(&nrg->link, rg->link.prev); 2845e911373SMike Kravetz 2855e911373SMike Kravetz add += t - f; 2865e911373SMike Kravetz goto out_locked; 2875e911373SMike Kravetz } 2885e911373SMike Kravetz 28996822904SAndy Whitcroft /* Round our left edge to the current segment if it encloses us. */ 29096822904SAndy Whitcroft if (f > rg->from) 29196822904SAndy Whitcroft f = rg->from; 29296822904SAndy Whitcroft 29396822904SAndy Whitcroft /* Check for and consume any regions we now overlap with. */ 29496822904SAndy Whitcroft nrg = rg; 29596822904SAndy Whitcroft list_for_each_entry_safe(rg, trg, rg->link.prev, link) { 29696822904SAndy Whitcroft if (&rg->link == head) 29796822904SAndy Whitcroft break; 29896822904SAndy Whitcroft if (rg->from > t) 29996822904SAndy Whitcroft break; 30096822904SAndy Whitcroft 30196822904SAndy Whitcroft /* If this area reaches higher then extend our area to 30296822904SAndy Whitcroft * include it completely. If this is not the first area 30396822904SAndy Whitcroft * which we intend to reuse, free it. */ 30496822904SAndy Whitcroft if (rg->to > t) 30596822904SAndy Whitcroft t = rg->to; 30696822904SAndy Whitcroft if (rg != nrg) { 307cf3ad20bSMike Kravetz /* Decrement return value by the deleted range. 308cf3ad20bSMike Kravetz * Another range will span this area so that by 309cf3ad20bSMike Kravetz * end of routine add will be >= zero 310cf3ad20bSMike Kravetz */ 311cf3ad20bSMike Kravetz add -= (rg->to - rg->from); 31296822904SAndy Whitcroft list_del(&rg->link); 31396822904SAndy Whitcroft kfree(rg); 31496822904SAndy Whitcroft } 31596822904SAndy Whitcroft } 316cf3ad20bSMike Kravetz 317cf3ad20bSMike Kravetz add += (nrg->from - f); /* Added to beginning of region */ 31896822904SAndy Whitcroft nrg->from = f; 319cf3ad20bSMike Kravetz add += t - nrg->to; /* Added to end of region */ 32096822904SAndy Whitcroft nrg->to = t; 321cf3ad20bSMike Kravetz 3225e911373SMike Kravetz out_locked: 3235e911373SMike Kravetz resv->adds_in_progress--; 3247b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 325cf3ad20bSMike Kravetz VM_BUG_ON(add < 0); 326cf3ad20bSMike Kravetz return add; 32796822904SAndy Whitcroft } 32896822904SAndy Whitcroft 3291dd308a7SMike Kravetz /* 3301dd308a7SMike Kravetz * Examine the existing reserve map and determine how many 3311dd308a7SMike Kravetz * huge pages in the specified range [f, t) are NOT currently 3321dd308a7SMike Kravetz * represented. This routine is called before a subsequent 3331dd308a7SMike Kravetz * call to region_add that will actually modify the reserve 3341dd308a7SMike Kravetz * map to add the specified range [f, t). region_chg does 3351dd308a7SMike Kravetz * not change the number of huge pages represented by the 3361dd308a7SMike Kravetz * map. However, if the existing regions in the map can not 3371dd308a7SMike Kravetz * be expanded to represent the new range, a new file_region 3381dd308a7SMike Kravetz * structure is added to the map as a placeholder. This is 3391dd308a7SMike Kravetz * so that the subsequent region_add call will have all the 3401dd308a7SMike Kravetz * regions it needs and will not fail. 3411dd308a7SMike Kravetz * 3425e911373SMike Kravetz * Upon entry, region_chg will also examine the cache of region descriptors 3435e911373SMike Kravetz * associated with the map. If there are not enough descriptors cached, one 3445e911373SMike Kravetz * will be allocated for the in progress add operation. 3455e911373SMike Kravetz * 3465e911373SMike Kravetz * Returns the number of huge pages that need to be added to the existing 3475e911373SMike Kravetz * reservation map for the range [f, t). This number is greater or equal to 3485e911373SMike Kravetz * zero. -ENOMEM is returned if a new file_region structure or cache entry 3495e911373SMike Kravetz * is needed and can not be allocated. 3501dd308a7SMike Kravetz */ 3511406ec9bSJoonsoo Kim static long region_chg(struct resv_map *resv, long f, long t) 35296822904SAndy Whitcroft { 3531406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 3547b24d861SDavidlohr Bueso struct file_region *rg, *nrg = NULL; 35596822904SAndy Whitcroft long chg = 0; 35696822904SAndy Whitcroft 3577b24d861SDavidlohr Bueso retry: 3587b24d861SDavidlohr Bueso spin_lock(&resv->lock); 3595e911373SMike Kravetz retry_locked: 3605e911373SMike Kravetz resv->adds_in_progress++; 3615e911373SMike Kravetz 3625e911373SMike Kravetz /* 3635e911373SMike Kravetz * Check for sufficient descriptors in the cache to accommodate 3645e911373SMike Kravetz * the number of in progress add operations. 3655e911373SMike Kravetz */ 3665e911373SMike Kravetz if (resv->adds_in_progress > resv->region_cache_count) { 3675e911373SMike Kravetz struct file_region *trg; 3685e911373SMike Kravetz 3695e911373SMike Kravetz VM_BUG_ON(resv->adds_in_progress - resv->region_cache_count > 1); 3705e911373SMike Kravetz /* Must drop lock to allocate a new descriptor. */ 3715e911373SMike Kravetz resv->adds_in_progress--; 3725e911373SMike Kravetz spin_unlock(&resv->lock); 3735e911373SMike Kravetz 3745e911373SMike Kravetz trg = kmalloc(sizeof(*trg), GFP_KERNEL); 3755e911373SMike Kravetz if (!trg) 3765e911373SMike Kravetz return -ENOMEM; 3775e911373SMike Kravetz 3785e911373SMike Kravetz spin_lock(&resv->lock); 3795e911373SMike Kravetz list_add(&trg->link, &resv->region_cache); 3805e911373SMike Kravetz resv->region_cache_count++; 3815e911373SMike Kravetz goto retry_locked; 3825e911373SMike Kravetz } 3835e911373SMike Kravetz 38496822904SAndy Whitcroft /* Locate the region we are before or in. */ 38596822904SAndy Whitcroft list_for_each_entry(rg, head, link) 38696822904SAndy Whitcroft if (f <= rg->to) 38796822904SAndy Whitcroft break; 38896822904SAndy Whitcroft 38996822904SAndy Whitcroft /* If we are below the current region then a new region is required. 39096822904SAndy Whitcroft * Subtle, allocate a new region at the position but make it zero 39196822904SAndy Whitcroft * size such that we can guarantee to record the reservation. */ 39296822904SAndy Whitcroft if (&rg->link == head || t < rg->from) { 3937b24d861SDavidlohr Bueso if (!nrg) { 3945e911373SMike Kravetz resv->adds_in_progress--; 3957b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 39696822904SAndy Whitcroft nrg = kmalloc(sizeof(*nrg), GFP_KERNEL); 39796822904SAndy Whitcroft if (!nrg) 39896822904SAndy Whitcroft return -ENOMEM; 3997b24d861SDavidlohr Bueso 40096822904SAndy Whitcroft nrg->from = f; 40196822904SAndy Whitcroft nrg->to = f; 40296822904SAndy Whitcroft INIT_LIST_HEAD(&nrg->link); 4037b24d861SDavidlohr Bueso goto retry; 4047b24d861SDavidlohr Bueso } 40596822904SAndy Whitcroft 4067b24d861SDavidlohr Bueso list_add(&nrg->link, rg->link.prev); 4077b24d861SDavidlohr Bueso chg = t - f; 4087b24d861SDavidlohr Bueso goto out_nrg; 40996822904SAndy Whitcroft } 41096822904SAndy Whitcroft 41196822904SAndy Whitcroft /* Round our left edge to the current segment if it encloses us. */ 41296822904SAndy Whitcroft if (f > rg->from) 41396822904SAndy Whitcroft f = rg->from; 41496822904SAndy Whitcroft chg = t - f; 41596822904SAndy Whitcroft 41696822904SAndy Whitcroft /* Check for and consume any regions we now overlap with. */ 41796822904SAndy Whitcroft list_for_each_entry(rg, rg->link.prev, link) { 41896822904SAndy Whitcroft if (&rg->link == head) 41996822904SAndy Whitcroft break; 42096822904SAndy Whitcroft if (rg->from > t) 4217b24d861SDavidlohr Bueso goto out; 42296822904SAndy Whitcroft 42325985edcSLucas De Marchi /* We overlap with this area, if it extends further than 42496822904SAndy Whitcroft * us then we must extend ourselves. Account for its 42596822904SAndy Whitcroft * existing reservation. */ 42696822904SAndy Whitcroft if (rg->to > t) { 42796822904SAndy Whitcroft chg += rg->to - t; 42896822904SAndy Whitcroft t = rg->to; 42996822904SAndy Whitcroft } 43096822904SAndy Whitcroft chg -= rg->to - rg->from; 43196822904SAndy Whitcroft } 4327b24d861SDavidlohr Bueso 4337b24d861SDavidlohr Bueso out: 4347b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 4357b24d861SDavidlohr Bueso /* We already know we raced and no longer need the new region */ 4367b24d861SDavidlohr Bueso kfree(nrg); 4377b24d861SDavidlohr Bueso return chg; 4387b24d861SDavidlohr Bueso out_nrg: 4397b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 44096822904SAndy Whitcroft return chg; 44196822904SAndy Whitcroft } 44296822904SAndy Whitcroft 4431dd308a7SMike Kravetz /* 4445e911373SMike Kravetz * Abort the in progress add operation. The adds_in_progress field 4455e911373SMike Kravetz * of the resv_map keeps track of the operations in progress between 4465e911373SMike Kravetz * calls to region_chg and region_add. Operations are sometimes 4475e911373SMike Kravetz * aborted after the call to region_chg. In such cases, region_abort 4485e911373SMike Kravetz * is called to decrement the adds_in_progress counter. 4495e911373SMike Kravetz * 4505e911373SMike Kravetz * NOTE: The range arguments [f, t) are not needed or used in this 4515e911373SMike Kravetz * routine. They are kept to make reading the calling code easier as 4525e911373SMike Kravetz * arguments will match the associated region_chg call. 4535e911373SMike Kravetz */ 4545e911373SMike Kravetz static void region_abort(struct resv_map *resv, long f, long t) 4555e911373SMike Kravetz { 4565e911373SMike Kravetz spin_lock(&resv->lock); 4575e911373SMike Kravetz VM_BUG_ON(!resv->region_cache_count); 4585e911373SMike Kravetz resv->adds_in_progress--; 4595e911373SMike Kravetz spin_unlock(&resv->lock); 4605e911373SMike Kravetz } 4615e911373SMike Kravetz 4625e911373SMike Kravetz /* 463feba16e2SMike Kravetz * Delete the specified range [f, t) from the reserve map. If the 464feba16e2SMike Kravetz * t parameter is LONG_MAX, this indicates that ALL regions after f 465feba16e2SMike Kravetz * should be deleted. Locate the regions which intersect [f, t) 466feba16e2SMike Kravetz * and either trim, delete or split the existing regions. 467feba16e2SMike Kravetz * 468feba16e2SMike Kravetz * Returns the number of huge pages deleted from the reserve map. 469feba16e2SMike Kravetz * In the normal case, the return value is zero or more. In the 470feba16e2SMike Kravetz * case where a region must be split, a new region descriptor must 471feba16e2SMike Kravetz * be allocated. If the allocation fails, -ENOMEM will be returned. 472feba16e2SMike Kravetz * NOTE: If the parameter t == LONG_MAX, then we will never split 473feba16e2SMike Kravetz * a region and possibly return -ENOMEM. Callers specifying 474feba16e2SMike Kravetz * t == LONG_MAX do not need to check for -ENOMEM error. 4751dd308a7SMike Kravetz */ 476feba16e2SMike Kravetz static long region_del(struct resv_map *resv, long f, long t) 47796822904SAndy Whitcroft { 4781406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 47996822904SAndy Whitcroft struct file_region *rg, *trg; 480feba16e2SMike Kravetz struct file_region *nrg = NULL; 481feba16e2SMike Kravetz long del = 0; 48296822904SAndy Whitcroft 483feba16e2SMike Kravetz retry: 4847b24d861SDavidlohr Bueso spin_lock(&resv->lock); 485feba16e2SMike Kravetz list_for_each_entry_safe(rg, trg, head, link) { 486feba16e2SMike Kravetz if (rg->to <= f) 487feba16e2SMike Kravetz continue; 488feba16e2SMike Kravetz if (rg->from >= t) 48996822904SAndy Whitcroft break; 49096822904SAndy Whitcroft 491feba16e2SMike Kravetz if (f > rg->from && t < rg->to) { /* Must split region */ 492feba16e2SMike Kravetz /* 493feba16e2SMike Kravetz * Check for an entry in the cache before dropping 494feba16e2SMike Kravetz * lock and attempting allocation. 495feba16e2SMike Kravetz */ 496feba16e2SMike Kravetz if (!nrg && 497feba16e2SMike Kravetz resv->region_cache_count > resv->adds_in_progress) { 498feba16e2SMike Kravetz nrg = list_first_entry(&resv->region_cache, 499feba16e2SMike Kravetz struct file_region, 500feba16e2SMike Kravetz link); 501feba16e2SMike Kravetz list_del(&nrg->link); 502feba16e2SMike Kravetz resv->region_cache_count--; 50396822904SAndy Whitcroft } 50496822904SAndy Whitcroft 505feba16e2SMike Kravetz if (!nrg) { 506feba16e2SMike Kravetz spin_unlock(&resv->lock); 507feba16e2SMike Kravetz nrg = kmalloc(sizeof(*nrg), GFP_KERNEL); 508feba16e2SMike Kravetz if (!nrg) 509feba16e2SMike Kravetz return -ENOMEM; 510feba16e2SMike Kravetz goto retry; 511feba16e2SMike Kravetz } 512feba16e2SMike Kravetz 513feba16e2SMike Kravetz del += t - f; 514feba16e2SMike Kravetz 515feba16e2SMike Kravetz /* New entry for end of split region */ 516feba16e2SMike Kravetz nrg->from = t; 517feba16e2SMike Kravetz nrg->to = rg->to; 518feba16e2SMike Kravetz INIT_LIST_HEAD(&nrg->link); 519feba16e2SMike Kravetz 520feba16e2SMike Kravetz /* Original entry is trimmed */ 521feba16e2SMike Kravetz rg->to = f; 522feba16e2SMike Kravetz 523feba16e2SMike Kravetz list_add(&nrg->link, &rg->link); 524feba16e2SMike Kravetz nrg = NULL; 52596822904SAndy Whitcroft break; 526feba16e2SMike Kravetz } 527feba16e2SMike Kravetz 528feba16e2SMike Kravetz if (f <= rg->from && t >= rg->to) { /* Remove entire region */ 529feba16e2SMike Kravetz del += rg->to - rg->from; 53096822904SAndy Whitcroft list_del(&rg->link); 53196822904SAndy Whitcroft kfree(rg); 532feba16e2SMike Kravetz continue; 53396822904SAndy Whitcroft } 5347b24d861SDavidlohr Bueso 535feba16e2SMike Kravetz if (f <= rg->from) { /* Trim beginning of region */ 536feba16e2SMike Kravetz del += t - rg->from; 537feba16e2SMike Kravetz rg->from = t; 538feba16e2SMike Kravetz } else { /* Trim end of region */ 539feba16e2SMike Kravetz del += rg->to - f; 540feba16e2SMike Kravetz rg->to = f; 541feba16e2SMike Kravetz } 542feba16e2SMike Kravetz } 543feba16e2SMike Kravetz 5447b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 545feba16e2SMike Kravetz kfree(nrg); 546feba16e2SMike Kravetz return del; 54796822904SAndy Whitcroft } 54896822904SAndy Whitcroft 5491dd308a7SMike Kravetz /* 550b5cec28dSMike Kravetz * A rare out of memory error was encountered which prevented removal of 551b5cec28dSMike Kravetz * the reserve map region for a page. The huge page itself was free'ed 552b5cec28dSMike Kravetz * and removed from the page cache. This routine will adjust the subpool 553b5cec28dSMike Kravetz * usage count, and the global reserve count if needed. By incrementing 554b5cec28dSMike Kravetz * these counts, the reserve map entry which could not be deleted will 555b5cec28dSMike Kravetz * appear as a "reserved" entry instead of simply dangling with incorrect 556b5cec28dSMike Kravetz * counts. 557b5cec28dSMike Kravetz */ 558b5cec28dSMike Kravetz void hugetlb_fix_reserve_counts(struct inode *inode, bool restore_reserve) 559b5cec28dSMike Kravetz { 560b5cec28dSMike Kravetz struct hugepage_subpool *spool = subpool_inode(inode); 561b5cec28dSMike Kravetz long rsv_adjust; 562b5cec28dSMike Kravetz 563b5cec28dSMike Kravetz rsv_adjust = hugepage_subpool_get_pages(spool, 1); 564b5cec28dSMike Kravetz if (restore_reserve && rsv_adjust) { 565b5cec28dSMike Kravetz struct hstate *h = hstate_inode(inode); 566b5cec28dSMike Kravetz 567b5cec28dSMike Kravetz hugetlb_acct_memory(h, 1); 568b5cec28dSMike Kravetz } 569b5cec28dSMike Kravetz } 570b5cec28dSMike Kravetz 571b5cec28dSMike Kravetz /* 5721dd308a7SMike Kravetz * Count and return the number of huge pages in the reserve map 5731dd308a7SMike Kravetz * that intersect with the range [f, t). 5741dd308a7SMike Kravetz */ 5751406ec9bSJoonsoo Kim static long region_count(struct resv_map *resv, long f, long t) 57684afd99bSAndy Whitcroft { 5771406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 57884afd99bSAndy Whitcroft struct file_region *rg; 57984afd99bSAndy Whitcroft long chg = 0; 58084afd99bSAndy Whitcroft 5817b24d861SDavidlohr Bueso spin_lock(&resv->lock); 58284afd99bSAndy Whitcroft /* Locate each segment we overlap with, and count that overlap. */ 58384afd99bSAndy Whitcroft list_for_each_entry(rg, head, link) { 584f2135a4aSWang Sheng-Hui long seg_from; 585f2135a4aSWang Sheng-Hui long seg_to; 58684afd99bSAndy Whitcroft 58784afd99bSAndy Whitcroft if (rg->to <= f) 58884afd99bSAndy Whitcroft continue; 58984afd99bSAndy Whitcroft if (rg->from >= t) 59084afd99bSAndy Whitcroft break; 59184afd99bSAndy Whitcroft 59284afd99bSAndy Whitcroft seg_from = max(rg->from, f); 59384afd99bSAndy Whitcroft seg_to = min(rg->to, t); 59484afd99bSAndy Whitcroft 59584afd99bSAndy Whitcroft chg += seg_to - seg_from; 59684afd99bSAndy Whitcroft } 5977b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 59884afd99bSAndy Whitcroft 59984afd99bSAndy Whitcroft return chg; 60084afd99bSAndy Whitcroft } 60184afd99bSAndy Whitcroft 60296822904SAndy Whitcroft /* 603e7c4b0bfSAndy Whitcroft * Convert the address within this vma to the page offset within 604e7c4b0bfSAndy Whitcroft * the mapping, in pagecache page units; huge pages here. 605e7c4b0bfSAndy Whitcroft */ 606a5516438SAndi Kleen static pgoff_t vma_hugecache_offset(struct hstate *h, 607a5516438SAndi Kleen struct vm_area_struct *vma, unsigned long address) 608e7c4b0bfSAndy Whitcroft { 609a5516438SAndi Kleen return ((address - vma->vm_start) >> huge_page_shift(h)) + 610a5516438SAndi Kleen (vma->vm_pgoff >> huge_page_order(h)); 611e7c4b0bfSAndy Whitcroft } 612e7c4b0bfSAndy Whitcroft 6130fe6e20bSNaoya Horiguchi pgoff_t linear_hugepage_index(struct vm_area_struct *vma, 6140fe6e20bSNaoya Horiguchi unsigned long address) 6150fe6e20bSNaoya Horiguchi { 6160fe6e20bSNaoya Horiguchi return vma_hugecache_offset(hstate_vma(vma), vma, address); 6170fe6e20bSNaoya Horiguchi } 6180fe6e20bSNaoya Horiguchi 61984afd99bSAndy Whitcroft /* 62008fba699SMel Gorman * Return the size of the pages allocated when backing a VMA. In the majority 62108fba699SMel Gorman * cases this will be same size as used by the page table entries. 62208fba699SMel Gorman */ 62308fba699SMel Gorman unsigned long vma_kernel_pagesize(struct vm_area_struct *vma) 62408fba699SMel Gorman { 62508fba699SMel Gorman struct hstate *hstate; 62608fba699SMel Gorman 62708fba699SMel Gorman if (!is_vm_hugetlb_page(vma)) 62808fba699SMel Gorman return PAGE_SIZE; 62908fba699SMel Gorman 63008fba699SMel Gorman hstate = hstate_vma(vma); 63108fba699SMel Gorman 6322415cf12SWanpeng Li return 1UL << huge_page_shift(hstate); 63308fba699SMel Gorman } 634f340ca0fSJoerg Roedel EXPORT_SYMBOL_GPL(vma_kernel_pagesize); 63508fba699SMel Gorman 63608fba699SMel Gorman /* 6373340289dSMel Gorman * Return the page size being used by the MMU to back a VMA. In the majority 6383340289dSMel Gorman * of cases, the page size used by the kernel matches the MMU size. On 6393340289dSMel Gorman * architectures where it differs, an architecture-specific version of this 6403340289dSMel Gorman * function is required. 6413340289dSMel Gorman */ 6423340289dSMel Gorman #ifndef vma_mmu_pagesize 6433340289dSMel Gorman unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) 6443340289dSMel Gorman { 6453340289dSMel Gorman return vma_kernel_pagesize(vma); 6463340289dSMel Gorman } 6473340289dSMel Gorman #endif 6483340289dSMel Gorman 6493340289dSMel Gorman /* 65084afd99bSAndy Whitcroft * Flags for MAP_PRIVATE reservations. These are stored in the bottom 65184afd99bSAndy Whitcroft * bits of the reservation map pointer, which are always clear due to 65284afd99bSAndy Whitcroft * alignment. 65384afd99bSAndy Whitcroft */ 65484afd99bSAndy Whitcroft #define HPAGE_RESV_OWNER (1UL << 0) 65584afd99bSAndy Whitcroft #define HPAGE_RESV_UNMAPPED (1UL << 1) 65604f2cbe3SMel Gorman #define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED) 65784afd99bSAndy Whitcroft 658a1e78772SMel Gorman /* 659a1e78772SMel Gorman * These helpers are used to track how many pages are reserved for 660a1e78772SMel Gorman * faults in a MAP_PRIVATE mapping. Only the process that called mmap() 661a1e78772SMel Gorman * is guaranteed to have their future faults succeed. 662a1e78772SMel Gorman * 663a1e78772SMel Gorman * With the exception of reset_vma_resv_huge_pages() which is called at fork(), 664a1e78772SMel Gorman * the reserve counters are updated with the hugetlb_lock held. It is safe 665a1e78772SMel Gorman * to reset the VMA at fork() time as it is not in use yet and there is no 666a1e78772SMel Gorman * chance of the global counters getting corrupted as a result of the values. 66784afd99bSAndy Whitcroft * 66884afd99bSAndy Whitcroft * The private mapping reservation is represented in a subtly different 66984afd99bSAndy Whitcroft * manner to a shared mapping. A shared mapping has a region map associated 67084afd99bSAndy Whitcroft * with the underlying file, this region map represents the backing file 67184afd99bSAndy Whitcroft * pages which have ever had a reservation assigned which this persists even 67284afd99bSAndy Whitcroft * after the page is instantiated. A private mapping has a region map 67384afd99bSAndy Whitcroft * associated with the original mmap which is attached to all VMAs which 67484afd99bSAndy Whitcroft * reference it, this region map represents those offsets which have consumed 67584afd99bSAndy Whitcroft * reservation ie. where pages have been instantiated. 676a1e78772SMel Gorman */ 677e7c4b0bfSAndy Whitcroft static unsigned long get_vma_private_data(struct vm_area_struct *vma) 678e7c4b0bfSAndy Whitcroft { 679e7c4b0bfSAndy Whitcroft return (unsigned long)vma->vm_private_data; 680e7c4b0bfSAndy Whitcroft } 681e7c4b0bfSAndy Whitcroft 682e7c4b0bfSAndy Whitcroft static void set_vma_private_data(struct vm_area_struct *vma, 683e7c4b0bfSAndy Whitcroft unsigned long value) 684e7c4b0bfSAndy Whitcroft { 685e7c4b0bfSAndy Whitcroft vma->vm_private_data = (void *)value; 686e7c4b0bfSAndy Whitcroft } 687e7c4b0bfSAndy Whitcroft 6889119a41eSJoonsoo Kim struct resv_map *resv_map_alloc(void) 68984afd99bSAndy Whitcroft { 69084afd99bSAndy Whitcroft struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL); 6915e911373SMike Kravetz struct file_region *rg = kmalloc(sizeof(*rg), GFP_KERNEL); 6925e911373SMike Kravetz 6935e911373SMike Kravetz if (!resv_map || !rg) { 6945e911373SMike Kravetz kfree(resv_map); 6955e911373SMike Kravetz kfree(rg); 69684afd99bSAndy Whitcroft return NULL; 6975e911373SMike Kravetz } 69884afd99bSAndy Whitcroft 69984afd99bSAndy Whitcroft kref_init(&resv_map->refs); 7007b24d861SDavidlohr Bueso spin_lock_init(&resv_map->lock); 70184afd99bSAndy Whitcroft INIT_LIST_HEAD(&resv_map->regions); 70284afd99bSAndy Whitcroft 7035e911373SMike Kravetz resv_map->adds_in_progress = 0; 7045e911373SMike Kravetz 7055e911373SMike Kravetz INIT_LIST_HEAD(&resv_map->region_cache); 7065e911373SMike Kravetz list_add(&rg->link, &resv_map->region_cache); 7075e911373SMike Kravetz resv_map->region_cache_count = 1; 7085e911373SMike Kravetz 70984afd99bSAndy Whitcroft return resv_map; 71084afd99bSAndy Whitcroft } 71184afd99bSAndy Whitcroft 7129119a41eSJoonsoo Kim void resv_map_release(struct kref *ref) 71384afd99bSAndy Whitcroft { 71484afd99bSAndy Whitcroft struct resv_map *resv_map = container_of(ref, struct resv_map, refs); 7155e911373SMike Kravetz struct list_head *head = &resv_map->region_cache; 7165e911373SMike Kravetz struct file_region *rg, *trg; 71784afd99bSAndy Whitcroft 71884afd99bSAndy Whitcroft /* Clear out any active regions before we release the map. */ 719feba16e2SMike Kravetz region_del(resv_map, 0, LONG_MAX); 7205e911373SMike Kravetz 7215e911373SMike Kravetz /* ... and any entries left in the cache */ 7225e911373SMike Kravetz list_for_each_entry_safe(rg, trg, head, link) { 7235e911373SMike Kravetz list_del(&rg->link); 7245e911373SMike Kravetz kfree(rg); 7255e911373SMike Kravetz } 7265e911373SMike Kravetz 7275e911373SMike Kravetz VM_BUG_ON(resv_map->adds_in_progress); 7285e911373SMike Kravetz 72984afd99bSAndy Whitcroft kfree(resv_map); 73084afd99bSAndy Whitcroft } 73184afd99bSAndy Whitcroft 7324e35f483SJoonsoo Kim static inline struct resv_map *inode_resv_map(struct inode *inode) 7334e35f483SJoonsoo Kim { 7344e35f483SJoonsoo Kim return inode->i_mapping->private_data; 7354e35f483SJoonsoo Kim } 7364e35f483SJoonsoo Kim 73784afd99bSAndy Whitcroft static struct resv_map *vma_resv_map(struct vm_area_struct *vma) 738a1e78772SMel Gorman { 73981d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 7404e35f483SJoonsoo Kim if (vma->vm_flags & VM_MAYSHARE) { 7414e35f483SJoonsoo Kim struct address_space *mapping = vma->vm_file->f_mapping; 7424e35f483SJoonsoo Kim struct inode *inode = mapping->host; 7434e35f483SJoonsoo Kim 7444e35f483SJoonsoo Kim return inode_resv_map(inode); 7454e35f483SJoonsoo Kim 7464e35f483SJoonsoo Kim } else { 74784afd99bSAndy Whitcroft return (struct resv_map *)(get_vma_private_data(vma) & 74884afd99bSAndy Whitcroft ~HPAGE_RESV_MASK); 7494e35f483SJoonsoo Kim } 750a1e78772SMel Gorman } 751a1e78772SMel Gorman 75284afd99bSAndy Whitcroft static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map) 753a1e78772SMel Gorman { 75481d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 75581d1b09cSSasha Levin VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); 756a1e78772SMel Gorman 75784afd99bSAndy Whitcroft set_vma_private_data(vma, (get_vma_private_data(vma) & 75884afd99bSAndy Whitcroft HPAGE_RESV_MASK) | (unsigned long)map); 75904f2cbe3SMel Gorman } 76004f2cbe3SMel Gorman 76104f2cbe3SMel Gorman static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags) 76204f2cbe3SMel Gorman { 76381d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 76481d1b09cSSasha Levin VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); 765e7c4b0bfSAndy Whitcroft 766e7c4b0bfSAndy Whitcroft set_vma_private_data(vma, get_vma_private_data(vma) | flags); 76704f2cbe3SMel Gorman } 76804f2cbe3SMel Gorman 76904f2cbe3SMel Gorman static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag) 77004f2cbe3SMel Gorman { 77181d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 772e7c4b0bfSAndy Whitcroft 773e7c4b0bfSAndy Whitcroft return (get_vma_private_data(vma) & flag) != 0; 774a1e78772SMel Gorman } 775a1e78772SMel Gorman 77604f2cbe3SMel Gorman /* Reset counters to 0 and clear all HPAGE_RESV_* flags */ 777a1e78772SMel Gorman void reset_vma_resv_huge_pages(struct vm_area_struct *vma) 778a1e78772SMel Gorman { 77981d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 780f83a275dSMel Gorman if (!(vma->vm_flags & VM_MAYSHARE)) 781a1e78772SMel Gorman vma->vm_private_data = (void *)0; 782a1e78772SMel Gorman } 783a1e78772SMel Gorman 784a1e78772SMel Gorman /* Returns true if the VMA has associated reserve pages */ 785559ec2f8SNicholas Krause static bool vma_has_reserves(struct vm_area_struct *vma, long chg) 786a1e78772SMel Gorman { 787af0ed73eSJoonsoo Kim if (vma->vm_flags & VM_NORESERVE) { 788af0ed73eSJoonsoo Kim /* 789af0ed73eSJoonsoo Kim * This address is already reserved by other process(chg == 0), 790af0ed73eSJoonsoo Kim * so, we should decrement reserved count. Without decrementing, 791af0ed73eSJoonsoo Kim * reserve count remains after releasing inode, because this 792af0ed73eSJoonsoo Kim * allocated page will go into page cache and is regarded as 793af0ed73eSJoonsoo Kim * coming from reserved pool in releasing step. Currently, we 794af0ed73eSJoonsoo Kim * don't have any other solution to deal with this situation 795af0ed73eSJoonsoo Kim * properly, so add work-around here. 796af0ed73eSJoonsoo Kim */ 797af0ed73eSJoonsoo Kim if (vma->vm_flags & VM_MAYSHARE && chg == 0) 798559ec2f8SNicholas Krause return true; 799af0ed73eSJoonsoo Kim else 800559ec2f8SNicholas Krause return false; 801af0ed73eSJoonsoo Kim } 802a63884e9SJoonsoo Kim 803a63884e9SJoonsoo Kim /* Shared mappings always use reserves */ 8041fb1b0e9SMike Kravetz if (vma->vm_flags & VM_MAYSHARE) { 8051fb1b0e9SMike Kravetz /* 8061fb1b0e9SMike Kravetz * We know VM_NORESERVE is not set. Therefore, there SHOULD 8071fb1b0e9SMike Kravetz * be a region map for all pages. The only situation where 8081fb1b0e9SMike Kravetz * there is no region map is if a hole was punched via 8091fb1b0e9SMike Kravetz * fallocate. In this case, there really are no reverves to 8101fb1b0e9SMike Kravetz * use. This situation is indicated if chg != 0. 8111fb1b0e9SMike Kravetz */ 8121fb1b0e9SMike Kravetz if (chg) 8131fb1b0e9SMike Kravetz return false; 8141fb1b0e9SMike Kravetz else 815559ec2f8SNicholas Krause return true; 8161fb1b0e9SMike Kravetz } 817a63884e9SJoonsoo Kim 818a63884e9SJoonsoo Kim /* 819a63884e9SJoonsoo Kim * Only the process that called mmap() has reserves for 820a63884e9SJoonsoo Kim * private mappings. 821a63884e9SJoonsoo Kim */ 8227f09ca51SMel Gorman if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) 823559ec2f8SNicholas Krause return true; 824a63884e9SJoonsoo Kim 825559ec2f8SNicholas Krause return false; 826a1e78772SMel Gorman } 827a1e78772SMel Gorman 828a5516438SAndi Kleen static void enqueue_huge_page(struct hstate *h, struct page *page) 8291da177e4SLinus Torvalds { 8301da177e4SLinus Torvalds int nid = page_to_nid(page); 8310edaecfaSAneesh Kumar K.V list_move(&page->lru, &h->hugepage_freelists[nid]); 832a5516438SAndi Kleen h->free_huge_pages++; 833a5516438SAndi Kleen h->free_huge_pages_node[nid]++; 8341da177e4SLinus Torvalds } 8351da177e4SLinus Torvalds 836bf50bab2SNaoya Horiguchi static struct page *dequeue_huge_page_node(struct hstate *h, int nid) 837bf50bab2SNaoya Horiguchi { 838bf50bab2SNaoya Horiguchi struct page *page; 839bf50bab2SNaoya Horiguchi 840c8721bbbSNaoya Horiguchi list_for_each_entry(page, &h->hugepage_freelists[nid], lru) 841c8721bbbSNaoya Horiguchi if (!is_migrate_isolate_page(page)) 842c8721bbbSNaoya Horiguchi break; 843c8721bbbSNaoya Horiguchi /* 844c8721bbbSNaoya Horiguchi * if 'non-isolated free hugepage' not found on the list, 845c8721bbbSNaoya Horiguchi * the allocation fails. 846c8721bbbSNaoya Horiguchi */ 847c8721bbbSNaoya Horiguchi if (&h->hugepage_freelists[nid] == &page->lru) 848bf50bab2SNaoya Horiguchi return NULL; 8490edaecfaSAneesh Kumar K.V list_move(&page->lru, &h->hugepage_activelist); 850a9869b83SNaoya Horiguchi set_page_refcounted(page); 851bf50bab2SNaoya Horiguchi h->free_huge_pages--; 852bf50bab2SNaoya Horiguchi h->free_huge_pages_node[nid]--; 853bf50bab2SNaoya Horiguchi return page; 854bf50bab2SNaoya Horiguchi } 855bf50bab2SNaoya Horiguchi 85686cdb465SNaoya Horiguchi /* Movability of hugepages depends on migration support. */ 85786cdb465SNaoya Horiguchi static inline gfp_t htlb_alloc_mask(struct hstate *h) 85886cdb465SNaoya Horiguchi { 859100873d7SNaoya Horiguchi if (hugepages_treat_as_movable || hugepage_migration_supported(h)) 86086cdb465SNaoya Horiguchi return GFP_HIGHUSER_MOVABLE; 86186cdb465SNaoya Horiguchi else 86286cdb465SNaoya Horiguchi return GFP_HIGHUSER; 86386cdb465SNaoya Horiguchi } 86486cdb465SNaoya Horiguchi 865a5516438SAndi Kleen static struct page *dequeue_huge_page_vma(struct hstate *h, 866a5516438SAndi Kleen struct vm_area_struct *vma, 867af0ed73eSJoonsoo Kim unsigned long address, int avoid_reserve, 868af0ed73eSJoonsoo Kim long chg) 8691da177e4SLinus Torvalds { 870b1c12cbcSKonstantin Khlebnikov struct page *page = NULL; 871480eccf9SLee Schermerhorn struct mempolicy *mpol; 87219770b32SMel Gorman nodemask_t *nodemask; 873c0ff7453SMiao Xie struct zonelist *zonelist; 874dd1a239fSMel Gorman struct zone *zone; 875dd1a239fSMel Gorman struct zoneref *z; 876cc9a6c87SMel Gorman unsigned int cpuset_mems_cookie; 8771da177e4SLinus Torvalds 878a1e78772SMel Gorman /* 879a1e78772SMel Gorman * A child process with MAP_PRIVATE mappings created by their parent 880a1e78772SMel Gorman * have no page reserves. This check ensures that reservations are 881a1e78772SMel Gorman * not "stolen". The child may still get SIGKILLed 882a1e78772SMel Gorman */ 883af0ed73eSJoonsoo Kim if (!vma_has_reserves(vma, chg) && 884a5516438SAndi Kleen h->free_huge_pages - h->resv_huge_pages == 0) 885c0ff7453SMiao Xie goto err; 886a1e78772SMel Gorman 88704f2cbe3SMel Gorman /* If reserves cannot be used, ensure enough pages are in the pool */ 888a5516438SAndi Kleen if (avoid_reserve && h->free_huge_pages - h->resv_huge_pages == 0) 8896eab04a8SJustin P. Mattock goto err; 89004f2cbe3SMel Gorman 8919966c4bbSJoonsoo Kim retry_cpuset: 892d26914d1SMel Gorman cpuset_mems_cookie = read_mems_allowed_begin(); 8939966c4bbSJoonsoo Kim zonelist = huge_zonelist(vma, address, 89486cdb465SNaoya Horiguchi htlb_alloc_mask(h), &mpol, &nodemask); 8959966c4bbSJoonsoo Kim 89619770b32SMel Gorman for_each_zone_zonelist_nodemask(zone, z, zonelist, 89719770b32SMel Gorman MAX_NR_ZONES - 1, nodemask) { 898344736f2SVladimir Davydov if (cpuset_zone_allowed(zone, htlb_alloc_mask(h))) { 899bf50bab2SNaoya Horiguchi page = dequeue_huge_page_node(h, zone_to_nid(zone)); 900bf50bab2SNaoya Horiguchi if (page) { 901af0ed73eSJoonsoo Kim if (avoid_reserve) 902af0ed73eSJoonsoo Kim break; 903af0ed73eSJoonsoo Kim if (!vma_has_reserves(vma, chg)) 904af0ed73eSJoonsoo Kim break; 905af0ed73eSJoonsoo Kim 90607443a85SJoonsoo Kim SetPagePrivate(page); 907a63884e9SJoonsoo Kim h->resv_huge_pages--; 9085ab3ee7bSKen Chen break; 9091da177e4SLinus Torvalds } 9103abf7afdSAndrew Morton } 911bf50bab2SNaoya Horiguchi } 912cc9a6c87SMel Gorman 913cc9a6c87SMel Gorman mpol_cond_put(mpol); 914d26914d1SMel Gorman if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie))) 915cc9a6c87SMel Gorman goto retry_cpuset; 916cc9a6c87SMel Gorman return page; 917cc9a6c87SMel Gorman 918c0ff7453SMiao Xie err: 919cc9a6c87SMel Gorman return NULL; 9201da177e4SLinus Torvalds } 9211da177e4SLinus Torvalds 9221cac6f2cSLuiz Capitulino /* 9231cac6f2cSLuiz Capitulino * common helper functions for hstate_next_node_to_{alloc|free}. 9241cac6f2cSLuiz Capitulino * We may have allocated or freed a huge page based on a different 9251cac6f2cSLuiz Capitulino * nodes_allowed previously, so h->next_node_to_{alloc|free} might 9261cac6f2cSLuiz Capitulino * be outside of *nodes_allowed. Ensure that we use an allowed 9271cac6f2cSLuiz Capitulino * node for alloc or free. 9281cac6f2cSLuiz Capitulino */ 9291cac6f2cSLuiz Capitulino static int next_node_allowed(int nid, nodemask_t *nodes_allowed) 9301cac6f2cSLuiz Capitulino { 9311cac6f2cSLuiz Capitulino nid = next_node(nid, *nodes_allowed); 9321cac6f2cSLuiz Capitulino if (nid == MAX_NUMNODES) 9331cac6f2cSLuiz Capitulino nid = first_node(*nodes_allowed); 9341cac6f2cSLuiz Capitulino VM_BUG_ON(nid >= MAX_NUMNODES); 9351cac6f2cSLuiz Capitulino 9361cac6f2cSLuiz Capitulino return nid; 9371cac6f2cSLuiz Capitulino } 9381cac6f2cSLuiz Capitulino 9391cac6f2cSLuiz Capitulino static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed) 9401cac6f2cSLuiz Capitulino { 9411cac6f2cSLuiz Capitulino if (!node_isset(nid, *nodes_allowed)) 9421cac6f2cSLuiz Capitulino nid = next_node_allowed(nid, nodes_allowed); 9431cac6f2cSLuiz Capitulino return nid; 9441cac6f2cSLuiz Capitulino } 9451cac6f2cSLuiz Capitulino 9461cac6f2cSLuiz Capitulino /* 9471cac6f2cSLuiz Capitulino * returns the previously saved node ["this node"] from which to 9481cac6f2cSLuiz Capitulino * allocate a persistent huge page for the pool and advance the 9491cac6f2cSLuiz Capitulino * next node from which to allocate, handling wrap at end of node 9501cac6f2cSLuiz Capitulino * mask. 9511cac6f2cSLuiz Capitulino */ 9521cac6f2cSLuiz Capitulino static int hstate_next_node_to_alloc(struct hstate *h, 9531cac6f2cSLuiz Capitulino nodemask_t *nodes_allowed) 9541cac6f2cSLuiz Capitulino { 9551cac6f2cSLuiz Capitulino int nid; 9561cac6f2cSLuiz Capitulino 9571cac6f2cSLuiz Capitulino VM_BUG_ON(!nodes_allowed); 9581cac6f2cSLuiz Capitulino 9591cac6f2cSLuiz Capitulino nid = get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed); 9601cac6f2cSLuiz Capitulino h->next_nid_to_alloc = next_node_allowed(nid, nodes_allowed); 9611cac6f2cSLuiz Capitulino 9621cac6f2cSLuiz Capitulino return nid; 9631cac6f2cSLuiz Capitulino } 9641cac6f2cSLuiz Capitulino 9651cac6f2cSLuiz Capitulino /* 9661cac6f2cSLuiz Capitulino * helper for free_pool_huge_page() - return the previously saved 9671cac6f2cSLuiz Capitulino * node ["this node"] from which to free a huge page. Advance the 9681cac6f2cSLuiz Capitulino * next node id whether or not we find a free huge page to free so 9691cac6f2cSLuiz Capitulino * that the next attempt to free addresses the next node. 9701cac6f2cSLuiz Capitulino */ 9711cac6f2cSLuiz Capitulino static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed) 9721cac6f2cSLuiz Capitulino { 9731cac6f2cSLuiz Capitulino int nid; 9741cac6f2cSLuiz Capitulino 9751cac6f2cSLuiz Capitulino VM_BUG_ON(!nodes_allowed); 9761cac6f2cSLuiz Capitulino 9771cac6f2cSLuiz Capitulino nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed); 9781cac6f2cSLuiz Capitulino h->next_nid_to_free = next_node_allowed(nid, nodes_allowed); 9791cac6f2cSLuiz Capitulino 9801cac6f2cSLuiz Capitulino return nid; 9811cac6f2cSLuiz Capitulino } 9821cac6f2cSLuiz Capitulino 9831cac6f2cSLuiz Capitulino #define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask) \ 9841cac6f2cSLuiz Capitulino for (nr_nodes = nodes_weight(*mask); \ 9851cac6f2cSLuiz Capitulino nr_nodes > 0 && \ 9861cac6f2cSLuiz Capitulino ((node = hstate_next_node_to_alloc(hs, mask)) || 1); \ 9871cac6f2cSLuiz Capitulino nr_nodes--) 9881cac6f2cSLuiz Capitulino 9891cac6f2cSLuiz Capitulino #define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \ 9901cac6f2cSLuiz Capitulino for (nr_nodes = nodes_weight(*mask); \ 9911cac6f2cSLuiz Capitulino nr_nodes > 0 && \ 9921cac6f2cSLuiz Capitulino ((node = hstate_next_node_to_free(hs, mask)) || 1); \ 9931cac6f2cSLuiz Capitulino nr_nodes--) 9941cac6f2cSLuiz Capitulino 995944d9fecSLuiz Capitulino #if defined(CONFIG_CMA) && defined(CONFIG_X86_64) 996944d9fecSLuiz Capitulino static void destroy_compound_gigantic_page(struct page *page, 997944d9fecSLuiz Capitulino unsigned long order) 998944d9fecSLuiz Capitulino { 999944d9fecSLuiz Capitulino int i; 1000944d9fecSLuiz Capitulino int nr_pages = 1 << order; 1001944d9fecSLuiz Capitulino struct page *p = page + 1; 1002944d9fecSLuiz Capitulino 1003944d9fecSLuiz Capitulino for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { 1004944d9fecSLuiz Capitulino __ClearPageTail(p); 1005944d9fecSLuiz Capitulino set_page_refcounted(p); 1006944d9fecSLuiz Capitulino p->first_page = NULL; 1007944d9fecSLuiz Capitulino } 1008944d9fecSLuiz Capitulino 1009944d9fecSLuiz Capitulino set_compound_order(page, 0); 1010944d9fecSLuiz Capitulino __ClearPageHead(page); 1011944d9fecSLuiz Capitulino } 1012944d9fecSLuiz Capitulino 1013944d9fecSLuiz Capitulino static void free_gigantic_page(struct page *page, unsigned order) 1014944d9fecSLuiz Capitulino { 1015944d9fecSLuiz Capitulino free_contig_range(page_to_pfn(page), 1 << order); 1016944d9fecSLuiz Capitulino } 1017944d9fecSLuiz Capitulino 1018944d9fecSLuiz Capitulino static int __alloc_gigantic_page(unsigned long start_pfn, 1019944d9fecSLuiz Capitulino unsigned long nr_pages) 1020944d9fecSLuiz Capitulino { 1021944d9fecSLuiz Capitulino unsigned long end_pfn = start_pfn + nr_pages; 1022944d9fecSLuiz Capitulino return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE); 1023944d9fecSLuiz Capitulino } 1024944d9fecSLuiz Capitulino 1025944d9fecSLuiz Capitulino static bool pfn_range_valid_gigantic(unsigned long start_pfn, 1026944d9fecSLuiz Capitulino unsigned long nr_pages) 1027944d9fecSLuiz Capitulino { 1028944d9fecSLuiz Capitulino unsigned long i, end_pfn = start_pfn + nr_pages; 1029944d9fecSLuiz Capitulino struct page *page; 1030944d9fecSLuiz Capitulino 1031944d9fecSLuiz Capitulino for (i = start_pfn; i < end_pfn; i++) { 1032944d9fecSLuiz Capitulino if (!pfn_valid(i)) 1033944d9fecSLuiz Capitulino return false; 1034944d9fecSLuiz Capitulino 1035944d9fecSLuiz Capitulino page = pfn_to_page(i); 1036944d9fecSLuiz Capitulino 1037944d9fecSLuiz Capitulino if (PageReserved(page)) 1038944d9fecSLuiz Capitulino return false; 1039944d9fecSLuiz Capitulino 1040944d9fecSLuiz Capitulino if (page_count(page) > 0) 1041944d9fecSLuiz Capitulino return false; 1042944d9fecSLuiz Capitulino 1043944d9fecSLuiz Capitulino if (PageHuge(page)) 1044944d9fecSLuiz Capitulino return false; 1045944d9fecSLuiz Capitulino } 1046944d9fecSLuiz Capitulino 1047944d9fecSLuiz Capitulino return true; 1048944d9fecSLuiz Capitulino } 1049944d9fecSLuiz Capitulino 1050944d9fecSLuiz Capitulino static bool zone_spans_last_pfn(const struct zone *zone, 1051944d9fecSLuiz Capitulino unsigned long start_pfn, unsigned long nr_pages) 1052944d9fecSLuiz Capitulino { 1053944d9fecSLuiz Capitulino unsigned long last_pfn = start_pfn + nr_pages - 1; 1054944d9fecSLuiz Capitulino return zone_spans_pfn(zone, last_pfn); 1055944d9fecSLuiz Capitulino } 1056944d9fecSLuiz Capitulino 1057944d9fecSLuiz Capitulino static struct page *alloc_gigantic_page(int nid, unsigned order) 1058944d9fecSLuiz Capitulino { 1059944d9fecSLuiz Capitulino unsigned long nr_pages = 1 << order; 1060944d9fecSLuiz Capitulino unsigned long ret, pfn, flags; 1061944d9fecSLuiz Capitulino struct zone *z; 1062944d9fecSLuiz Capitulino 1063944d9fecSLuiz Capitulino z = NODE_DATA(nid)->node_zones; 1064944d9fecSLuiz Capitulino for (; z - NODE_DATA(nid)->node_zones < MAX_NR_ZONES; z++) { 1065944d9fecSLuiz Capitulino spin_lock_irqsave(&z->lock, flags); 1066944d9fecSLuiz Capitulino 1067944d9fecSLuiz Capitulino pfn = ALIGN(z->zone_start_pfn, nr_pages); 1068944d9fecSLuiz Capitulino while (zone_spans_last_pfn(z, pfn, nr_pages)) { 1069944d9fecSLuiz Capitulino if (pfn_range_valid_gigantic(pfn, nr_pages)) { 1070944d9fecSLuiz Capitulino /* 1071944d9fecSLuiz Capitulino * We release the zone lock here because 1072944d9fecSLuiz Capitulino * alloc_contig_range() will also lock the zone 1073944d9fecSLuiz Capitulino * at some point. If there's an allocation 1074944d9fecSLuiz Capitulino * spinning on this lock, it may win the race 1075944d9fecSLuiz Capitulino * and cause alloc_contig_range() to fail... 1076944d9fecSLuiz Capitulino */ 1077944d9fecSLuiz Capitulino spin_unlock_irqrestore(&z->lock, flags); 1078944d9fecSLuiz Capitulino ret = __alloc_gigantic_page(pfn, nr_pages); 1079944d9fecSLuiz Capitulino if (!ret) 1080944d9fecSLuiz Capitulino return pfn_to_page(pfn); 1081944d9fecSLuiz Capitulino spin_lock_irqsave(&z->lock, flags); 1082944d9fecSLuiz Capitulino } 1083944d9fecSLuiz Capitulino pfn += nr_pages; 1084944d9fecSLuiz Capitulino } 1085944d9fecSLuiz Capitulino 1086944d9fecSLuiz Capitulino spin_unlock_irqrestore(&z->lock, flags); 1087944d9fecSLuiz Capitulino } 1088944d9fecSLuiz Capitulino 1089944d9fecSLuiz Capitulino return NULL; 1090944d9fecSLuiz Capitulino } 1091944d9fecSLuiz Capitulino 1092944d9fecSLuiz Capitulino static void prep_new_huge_page(struct hstate *h, struct page *page, int nid); 1093944d9fecSLuiz Capitulino static void prep_compound_gigantic_page(struct page *page, unsigned long order); 1094944d9fecSLuiz Capitulino 1095944d9fecSLuiz Capitulino static struct page *alloc_fresh_gigantic_page_node(struct hstate *h, int nid) 1096944d9fecSLuiz Capitulino { 1097944d9fecSLuiz Capitulino struct page *page; 1098944d9fecSLuiz Capitulino 1099944d9fecSLuiz Capitulino page = alloc_gigantic_page(nid, huge_page_order(h)); 1100944d9fecSLuiz Capitulino if (page) { 1101944d9fecSLuiz Capitulino prep_compound_gigantic_page(page, huge_page_order(h)); 1102944d9fecSLuiz Capitulino prep_new_huge_page(h, page, nid); 1103944d9fecSLuiz Capitulino } 1104944d9fecSLuiz Capitulino 1105944d9fecSLuiz Capitulino return page; 1106944d9fecSLuiz Capitulino } 1107944d9fecSLuiz Capitulino 1108944d9fecSLuiz Capitulino static int alloc_fresh_gigantic_page(struct hstate *h, 1109944d9fecSLuiz Capitulino nodemask_t *nodes_allowed) 1110944d9fecSLuiz Capitulino { 1111944d9fecSLuiz Capitulino struct page *page = NULL; 1112944d9fecSLuiz Capitulino int nr_nodes, node; 1113944d9fecSLuiz Capitulino 1114944d9fecSLuiz Capitulino for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { 1115944d9fecSLuiz Capitulino page = alloc_fresh_gigantic_page_node(h, node); 1116944d9fecSLuiz Capitulino if (page) 1117944d9fecSLuiz Capitulino return 1; 1118944d9fecSLuiz Capitulino } 1119944d9fecSLuiz Capitulino 1120944d9fecSLuiz Capitulino return 0; 1121944d9fecSLuiz Capitulino } 1122944d9fecSLuiz Capitulino 1123944d9fecSLuiz Capitulino static inline bool gigantic_page_supported(void) { return true; } 1124944d9fecSLuiz Capitulino #else 1125944d9fecSLuiz Capitulino static inline bool gigantic_page_supported(void) { return false; } 1126944d9fecSLuiz Capitulino static inline void free_gigantic_page(struct page *page, unsigned order) { } 1127944d9fecSLuiz Capitulino static inline void destroy_compound_gigantic_page(struct page *page, 1128944d9fecSLuiz Capitulino unsigned long order) { } 1129944d9fecSLuiz Capitulino static inline int alloc_fresh_gigantic_page(struct hstate *h, 1130944d9fecSLuiz Capitulino nodemask_t *nodes_allowed) { return 0; } 1131944d9fecSLuiz Capitulino #endif 1132944d9fecSLuiz Capitulino 1133a5516438SAndi Kleen static void update_and_free_page(struct hstate *h, struct page *page) 11346af2acb6SAdam Litke { 11356af2acb6SAdam Litke int i; 1136a5516438SAndi Kleen 1137944d9fecSLuiz Capitulino if (hstate_is_gigantic(h) && !gigantic_page_supported()) 1138944d9fecSLuiz Capitulino return; 113918229df5SAndy Whitcroft 1140a5516438SAndi Kleen h->nr_huge_pages--; 1141a5516438SAndi Kleen h->nr_huge_pages_node[page_to_nid(page)]--; 1142a5516438SAndi Kleen for (i = 0; i < pages_per_huge_page(h); i++) { 114332f84528SChris Forbes page[i].flags &= ~(1 << PG_locked | 1 << PG_error | 114432f84528SChris Forbes 1 << PG_referenced | 1 << PG_dirty | 1145a7407a27SLuiz Capitulino 1 << PG_active | 1 << PG_private | 1146a7407a27SLuiz Capitulino 1 << PG_writeback); 11476af2acb6SAdam Litke } 1148309381feSSasha Levin VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page), page); 11496af2acb6SAdam Litke set_compound_page_dtor(page, NULL); 11506af2acb6SAdam Litke set_page_refcounted(page); 1151944d9fecSLuiz Capitulino if (hstate_is_gigantic(h)) { 1152944d9fecSLuiz Capitulino destroy_compound_gigantic_page(page, huge_page_order(h)); 1153944d9fecSLuiz Capitulino free_gigantic_page(page, huge_page_order(h)); 1154944d9fecSLuiz Capitulino } else { 1155a5516438SAndi Kleen __free_pages(page, huge_page_order(h)); 11566af2acb6SAdam Litke } 1157944d9fecSLuiz Capitulino } 11586af2acb6SAdam Litke 1159e5ff2159SAndi Kleen struct hstate *size_to_hstate(unsigned long size) 1160e5ff2159SAndi Kleen { 1161e5ff2159SAndi Kleen struct hstate *h; 1162e5ff2159SAndi Kleen 1163e5ff2159SAndi Kleen for_each_hstate(h) { 1164e5ff2159SAndi Kleen if (huge_page_size(h) == size) 1165e5ff2159SAndi Kleen return h; 1166e5ff2159SAndi Kleen } 1167e5ff2159SAndi Kleen return NULL; 1168e5ff2159SAndi Kleen } 1169e5ff2159SAndi Kleen 1170bcc54222SNaoya Horiguchi /* 1171bcc54222SNaoya Horiguchi * Test to determine whether the hugepage is "active/in-use" (i.e. being linked 1172bcc54222SNaoya Horiguchi * to hstate->hugepage_activelist.) 1173bcc54222SNaoya Horiguchi * 1174bcc54222SNaoya Horiguchi * This function can be called for tail pages, but never returns true for them. 1175bcc54222SNaoya Horiguchi */ 1176bcc54222SNaoya Horiguchi bool page_huge_active(struct page *page) 1177bcc54222SNaoya Horiguchi { 1178bcc54222SNaoya Horiguchi VM_BUG_ON_PAGE(!PageHuge(page), page); 1179bcc54222SNaoya Horiguchi return PageHead(page) && PagePrivate(&page[1]); 1180bcc54222SNaoya Horiguchi } 1181bcc54222SNaoya Horiguchi 1182bcc54222SNaoya Horiguchi /* never called for tail page */ 1183bcc54222SNaoya Horiguchi static void set_page_huge_active(struct page *page) 1184bcc54222SNaoya Horiguchi { 1185bcc54222SNaoya Horiguchi VM_BUG_ON_PAGE(!PageHeadHuge(page), page); 1186bcc54222SNaoya Horiguchi SetPagePrivate(&page[1]); 1187bcc54222SNaoya Horiguchi } 1188bcc54222SNaoya Horiguchi 1189bcc54222SNaoya Horiguchi static void clear_page_huge_active(struct page *page) 1190bcc54222SNaoya Horiguchi { 1191bcc54222SNaoya Horiguchi VM_BUG_ON_PAGE(!PageHeadHuge(page), page); 1192bcc54222SNaoya Horiguchi ClearPagePrivate(&page[1]); 1193bcc54222SNaoya Horiguchi } 1194bcc54222SNaoya Horiguchi 11958f1d26d0SAtsushi Kumagai void free_huge_page(struct page *page) 119627a85ef1SDavid Gibson { 1197a5516438SAndi Kleen /* 1198a5516438SAndi Kleen * Can't pass hstate in here because it is called from the 1199a5516438SAndi Kleen * compound page destructor. 1200a5516438SAndi Kleen */ 1201e5ff2159SAndi Kleen struct hstate *h = page_hstate(page); 12027893d1d5SAdam Litke int nid = page_to_nid(page); 120390481622SDavid Gibson struct hugepage_subpool *spool = 120490481622SDavid Gibson (struct hugepage_subpool *)page_private(page); 120507443a85SJoonsoo Kim bool restore_reserve; 120627a85ef1SDavid Gibson 1207e5df70abSAndy Whitcroft set_page_private(page, 0); 120823be7468SMel Gorman page->mapping = NULL; 12097893d1d5SAdam Litke BUG_ON(page_count(page)); 12100fe6e20bSNaoya Horiguchi BUG_ON(page_mapcount(page)); 121107443a85SJoonsoo Kim restore_reserve = PagePrivate(page); 121216c794b4SJoonsoo Kim ClearPagePrivate(page); 121327a85ef1SDavid Gibson 12141c5ecae3SMike Kravetz /* 12151c5ecae3SMike Kravetz * A return code of zero implies that the subpool will be under its 12161c5ecae3SMike Kravetz * minimum size if the reservation is not restored after page is free. 12171c5ecae3SMike Kravetz * Therefore, force restore_reserve operation. 12181c5ecae3SMike Kravetz */ 12191c5ecae3SMike Kravetz if (hugepage_subpool_put_pages(spool, 1) == 0) 12201c5ecae3SMike Kravetz restore_reserve = true; 12211c5ecae3SMike Kravetz 122227a85ef1SDavid Gibson spin_lock(&hugetlb_lock); 1223bcc54222SNaoya Horiguchi clear_page_huge_active(page); 12246d76dcf4SAneesh Kumar K.V hugetlb_cgroup_uncharge_page(hstate_index(h), 12256d76dcf4SAneesh Kumar K.V pages_per_huge_page(h), page); 122607443a85SJoonsoo Kim if (restore_reserve) 122707443a85SJoonsoo Kim h->resv_huge_pages++; 122807443a85SJoonsoo Kim 1229944d9fecSLuiz Capitulino if (h->surplus_huge_pages_node[nid]) { 12300edaecfaSAneesh Kumar K.V /* remove the page from active list */ 12310edaecfaSAneesh Kumar K.V list_del(&page->lru); 1232a5516438SAndi Kleen update_and_free_page(h, page); 1233a5516438SAndi Kleen h->surplus_huge_pages--; 1234a5516438SAndi Kleen h->surplus_huge_pages_node[nid]--; 12357893d1d5SAdam Litke } else { 12365d3a551cSWill Deacon arch_clear_hugepage_flags(page); 1237a5516438SAndi Kleen enqueue_huge_page(h, page); 12387893d1d5SAdam Litke } 123927a85ef1SDavid Gibson spin_unlock(&hugetlb_lock); 124027a85ef1SDavid Gibson } 124127a85ef1SDavid Gibson 1242a5516438SAndi Kleen static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) 1243b7ba30c6SAndi Kleen { 12440edaecfaSAneesh Kumar K.V INIT_LIST_HEAD(&page->lru); 1245b7ba30c6SAndi Kleen set_compound_page_dtor(page, free_huge_page); 1246b7ba30c6SAndi Kleen spin_lock(&hugetlb_lock); 12479dd540e2SAneesh Kumar K.V set_hugetlb_cgroup(page, NULL); 1248a5516438SAndi Kleen h->nr_huge_pages++; 1249a5516438SAndi Kleen h->nr_huge_pages_node[nid]++; 1250b7ba30c6SAndi Kleen spin_unlock(&hugetlb_lock); 1251b7ba30c6SAndi Kleen put_page(page); /* free it into the hugepage allocator */ 1252b7ba30c6SAndi Kleen } 1253b7ba30c6SAndi Kleen 12542906dd52SLuiz Capitulino static void prep_compound_gigantic_page(struct page *page, unsigned long order) 125520a0307cSWu Fengguang { 125620a0307cSWu Fengguang int i; 125720a0307cSWu Fengguang int nr_pages = 1 << order; 125820a0307cSWu Fengguang struct page *p = page + 1; 125920a0307cSWu Fengguang 126020a0307cSWu Fengguang /* we rely on prep_new_huge_page to set the destructor */ 126120a0307cSWu Fengguang set_compound_order(page, order); 126220a0307cSWu Fengguang __SetPageHead(page); 1263ef5a22beSAndrea Arcangeli __ClearPageReserved(page); 126420a0307cSWu Fengguang for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { 1265ef5a22beSAndrea Arcangeli /* 1266ef5a22beSAndrea Arcangeli * For gigantic hugepages allocated through bootmem at 1267ef5a22beSAndrea Arcangeli * boot, it's safer to be consistent with the not-gigantic 1268ef5a22beSAndrea Arcangeli * hugepages and clear the PG_reserved bit from all tail pages 1269ef5a22beSAndrea Arcangeli * too. Otherwse drivers using get_user_pages() to access tail 1270ef5a22beSAndrea Arcangeli * pages may get the reference counting wrong if they see 1271ef5a22beSAndrea Arcangeli * PG_reserved set on a tail page (despite the head page not 1272ef5a22beSAndrea Arcangeli * having PG_reserved set). Enforcing this consistency between 1273ef5a22beSAndrea Arcangeli * head and tail pages allows drivers to optimize away a check 1274ef5a22beSAndrea Arcangeli * on the head page when they need know if put_page() is needed 1275ef5a22beSAndrea Arcangeli * after get_user_pages(). 1276ef5a22beSAndrea Arcangeli */ 1277ef5a22beSAndrea Arcangeli __ClearPageReserved(p); 127858a84aa9SYouquan Song set_page_count(p, 0); 127920a0307cSWu Fengguang p->first_page = page; 128044fc8057SDavid Rientjes /* Make sure p->first_page is always valid for PageTail() */ 128144fc8057SDavid Rientjes smp_wmb(); 128244fc8057SDavid Rientjes __SetPageTail(p); 128320a0307cSWu Fengguang } 128420a0307cSWu Fengguang } 128520a0307cSWu Fengguang 12867795912cSAndrew Morton /* 12877795912cSAndrew Morton * PageHuge() only returns true for hugetlbfs pages, but not for normal or 12887795912cSAndrew Morton * transparent huge pages. See the PageTransHuge() documentation for more 12897795912cSAndrew Morton * details. 12907795912cSAndrew Morton */ 129120a0307cSWu Fengguang int PageHuge(struct page *page) 129220a0307cSWu Fengguang { 129320a0307cSWu Fengguang if (!PageCompound(page)) 129420a0307cSWu Fengguang return 0; 129520a0307cSWu Fengguang 129620a0307cSWu Fengguang page = compound_head(page); 1297758f66a2SAndrew Morton return get_compound_page_dtor(page) == free_huge_page; 129820a0307cSWu Fengguang } 129943131e14SNaoya Horiguchi EXPORT_SYMBOL_GPL(PageHuge); 130043131e14SNaoya Horiguchi 130127c73ae7SAndrea Arcangeli /* 130227c73ae7SAndrea Arcangeli * PageHeadHuge() only returns true for hugetlbfs head page, but not for 130327c73ae7SAndrea Arcangeli * normal or transparent huge pages. 130427c73ae7SAndrea Arcangeli */ 130527c73ae7SAndrea Arcangeli int PageHeadHuge(struct page *page_head) 130627c73ae7SAndrea Arcangeli { 130727c73ae7SAndrea Arcangeli if (!PageHead(page_head)) 130827c73ae7SAndrea Arcangeli return 0; 130927c73ae7SAndrea Arcangeli 1310758f66a2SAndrew Morton return get_compound_page_dtor(page_head) == free_huge_page; 131127c73ae7SAndrea Arcangeli } 131227c73ae7SAndrea Arcangeli 131313d60f4bSZhang Yi pgoff_t __basepage_index(struct page *page) 131413d60f4bSZhang Yi { 131513d60f4bSZhang Yi struct page *page_head = compound_head(page); 131613d60f4bSZhang Yi pgoff_t index = page_index(page_head); 131713d60f4bSZhang Yi unsigned long compound_idx; 131813d60f4bSZhang Yi 131913d60f4bSZhang Yi if (!PageHuge(page_head)) 132013d60f4bSZhang Yi return page_index(page); 132113d60f4bSZhang Yi 132213d60f4bSZhang Yi if (compound_order(page_head) >= MAX_ORDER) 132313d60f4bSZhang Yi compound_idx = page_to_pfn(page) - page_to_pfn(page_head); 132413d60f4bSZhang Yi else 132513d60f4bSZhang Yi compound_idx = page - page_head; 132613d60f4bSZhang Yi 132713d60f4bSZhang Yi return (index << compound_order(page_head)) + compound_idx; 132813d60f4bSZhang Yi } 132913d60f4bSZhang Yi 1330a5516438SAndi Kleen static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) 13311da177e4SLinus Torvalds { 13321da177e4SLinus Torvalds struct page *page; 1333f96efd58SJoe Jin 133496db800fSVlastimil Babka page = __alloc_pages_node(nid, 133586cdb465SNaoya Horiguchi htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE| 1336551883aeSNishanth Aravamudan __GFP_REPEAT|__GFP_NOWARN, 1337a5516438SAndi Kleen huge_page_order(h)); 13381da177e4SLinus Torvalds if (page) { 1339a5516438SAndi Kleen prep_new_huge_page(h, page, nid); 13401da177e4SLinus Torvalds } 134163b4613cSNishanth Aravamudan 134263b4613cSNishanth Aravamudan return page; 134363b4613cSNishanth Aravamudan } 134463b4613cSNishanth Aravamudan 1345b2261026SJoonsoo Kim static int alloc_fresh_huge_page(struct hstate *h, nodemask_t *nodes_allowed) 1346b2261026SJoonsoo Kim { 1347b2261026SJoonsoo Kim struct page *page; 1348b2261026SJoonsoo Kim int nr_nodes, node; 1349b2261026SJoonsoo Kim int ret = 0; 1350b2261026SJoonsoo Kim 1351b2261026SJoonsoo Kim for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { 1352b2261026SJoonsoo Kim page = alloc_fresh_huge_page_node(h, node); 1353b2261026SJoonsoo Kim if (page) { 1354b2261026SJoonsoo Kim ret = 1; 1355b2261026SJoonsoo Kim break; 1356b2261026SJoonsoo Kim } 1357b2261026SJoonsoo Kim } 1358b2261026SJoonsoo Kim 1359b2261026SJoonsoo Kim if (ret) 1360b2261026SJoonsoo Kim count_vm_event(HTLB_BUDDY_PGALLOC); 1361b2261026SJoonsoo Kim else 1362b2261026SJoonsoo Kim count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); 1363b2261026SJoonsoo Kim 1364b2261026SJoonsoo Kim return ret; 1365b2261026SJoonsoo Kim } 1366b2261026SJoonsoo Kim 1367e8c5c824SLee Schermerhorn /* 1368e8c5c824SLee Schermerhorn * Free huge page from pool from next node to free. 1369e8c5c824SLee Schermerhorn * Attempt to keep persistent huge pages more or less 1370e8c5c824SLee Schermerhorn * balanced over allowed nodes. 1371e8c5c824SLee Schermerhorn * Called with hugetlb_lock locked. 1372e8c5c824SLee Schermerhorn */ 13736ae11b27SLee Schermerhorn static int free_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed, 13746ae11b27SLee Schermerhorn bool acct_surplus) 1375e8c5c824SLee Schermerhorn { 1376b2261026SJoonsoo Kim int nr_nodes, node; 1377e8c5c824SLee Schermerhorn int ret = 0; 1378e8c5c824SLee Schermerhorn 1379b2261026SJoonsoo Kim for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { 1380685f3457SLee Schermerhorn /* 1381685f3457SLee Schermerhorn * If we're returning unused surplus pages, only examine 1382685f3457SLee Schermerhorn * nodes with surplus pages. 1383685f3457SLee Schermerhorn */ 1384b2261026SJoonsoo Kim if ((!acct_surplus || h->surplus_huge_pages_node[node]) && 1385b2261026SJoonsoo Kim !list_empty(&h->hugepage_freelists[node])) { 1386e8c5c824SLee Schermerhorn struct page *page = 1387b2261026SJoonsoo Kim list_entry(h->hugepage_freelists[node].next, 1388e8c5c824SLee Schermerhorn struct page, lru); 1389e8c5c824SLee Schermerhorn list_del(&page->lru); 1390e8c5c824SLee Schermerhorn h->free_huge_pages--; 1391b2261026SJoonsoo Kim h->free_huge_pages_node[node]--; 1392685f3457SLee Schermerhorn if (acct_surplus) { 1393685f3457SLee Schermerhorn h->surplus_huge_pages--; 1394b2261026SJoonsoo Kim h->surplus_huge_pages_node[node]--; 1395685f3457SLee Schermerhorn } 1396e8c5c824SLee Schermerhorn update_and_free_page(h, page); 1397e8c5c824SLee Schermerhorn ret = 1; 13989a76db09SLee Schermerhorn break; 1399e8c5c824SLee Schermerhorn } 1400b2261026SJoonsoo Kim } 1401e8c5c824SLee Schermerhorn 1402e8c5c824SLee Schermerhorn return ret; 1403e8c5c824SLee Schermerhorn } 1404e8c5c824SLee Schermerhorn 1405c8721bbbSNaoya Horiguchi /* 1406c8721bbbSNaoya Horiguchi * Dissolve a given free hugepage into free buddy pages. This function does 1407c8721bbbSNaoya Horiguchi * nothing for in-use (including surplus) hugepages. 1408c8721bbbSNaoya Horiguchi */ 1409c8721bbbSNaoya Horiguchi static void dissolve_free_huge_page(struct page *page) 1410c8721bbbSNaoya Horiguchi { 1411c8721bbbSNaoya Horiguchi spin_lock(&hugetlb_lock); 1412c8721bbbSNaoya Horiguchi if (PageHuge(page) && !page_count(page)) { 1413c8721bbbSNaoya Horiguchi struct hstate *h = page_hstate(page); 1414c8721bbbSNaoya Horiguchi int nid = page_to_nid(page); 1415c8721bbbSNaoya Horiguchi list_del(&page->lru); 1416c8721bbbSNaoya Horiguchi h->free_huge_pages--; 1417c8721bbbSNaoya Horiguchi h->free_huge_pages_node[nid]--; 1418c8721bbbSNaoya Horiguchi update_and_free_page(h, page); 1419c8721bbbSNaoya Horiguchi } 1420c8721bbbSNaoya Horiguchi spin_unlock(&hugetlb_lock); 1421c8721bbbSNaoya Horiguchi } 1422c8721bbbSNaoya Horiguchi 1423c8721bbbSNaoya Horiguchi /* 1424c8721bbbSNaoya Horiguchi * Dissolve free hugepages in a given pfn range. Used by memory hotplug to 1425c8721bbbSNaoya Horiguchi * make specified memory blocks removable from the system. 1426c8721bbbSNaoya Horiguchi * Note that start_pfn should aligned with (minimum) hugepage size. 1427c8721bbbSNaoya Horiguchi */ 1428c8721bbbSNaoya Horiguchi void dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn) 1429c8721bbbSNaoya Horiguchi { 1430c8721bbbSNaoya Horiguchi unsigned long pfn; 1431c8721bbbSNaoya Horiguchi 1432d0177639SLi Zhong if (!hugepages_supported()) 1433d0177639SLi Zhong return; 1434d0177639SLi Zhong 1435641844f5SNaoya Horiguchi VM_BUG_ON(!IS_ALIGNED(start_pfn, 1 << minimum_order)); 1436641844f5SNaoya Horiguchi for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << minimum_order) 1437c8721bbbSNaoya Horiguchi dissolve_free_huge_page(pfn_to_page(pfn)); 1438c8721bbbSNaoya Horiguchi } 1439c8721bbbSNaoya Horiguchi 1440bf50bab2SNaoya Horiguchi static struct page *alloc_buddy_huge_page(struct hstate *h, int nid) 14417893d1d5SAdam Litke { 14427893d1d5SAdam Litke struct page *page; 1443bf50bab2SNaoya Horiguchi unsigned int r_nid; 14447893d1d5SAdam Litke 1445bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 1446aa888a74SAndi Kleen return NULL; 1447aa888a74SAndi Kleen 1448d1c3fb1fSNishanth Aravamudan /* 1449d1c3fb1fSNishanth Aravamudan * Assume we will successfully allocate the surplus page to 1450d1c3fb1fSNishanth Aravamudan * prevent racing processes from causing the surplus to exceed 1451d1c3fb1fSNishanth Aravamudan * overcommit 1452d1c3fb1fSNishanth Aravamudan * 1453d1c3fb1fSNishanth Aravamudan * This however introduces a different race, where a process B 1454d1c3fb1fSNishanth Aravamudan * tries to grow the static hugepage pool while alloc_pages() is 1455d1c3fb1fSNishanth Aravamudan * called by process A. B will only examine the per-node 1456d1c3fb1fSNishanth Aravamudan * counters in determining if surplus huge pages can be 1457d1c3fb1fSNishanth Aravamudan * converted to normal huge pages in adjust_pool_surplus(). A 1458d1c3fb1fSNishanth Aravamudan * won't be able to increment the per-node counter, until the 1459d1c3fb1fSNishanth Aravamudan * lock is dropped by B, but B doesn't drop hugetlb_lock until 1460d1c3fb1fSNishanth Aravamudan * no more huge pages can be converted from surplus to normal 1461d1c3fb1fSNishanth Aravamudan * state (and doesn't try to convert again). Thus, we have a 1462d1c3fb1fSNishanth Aravamudan * case where a surplus huge page exists, the pool is grown, and 1463d1c3fb1fSNishanth Aravamudan * the surplus huge page still exists after, even though it 1464d1c3fb1fSNishanth Aravamudan * should just have been converted to a normal huge page. This 1465d1c3fb1fSNishanth Aravamudan * does not leak memory, though, as the hugepage will be freed 1466d1c3fb1fSNishanth Aravamudan * once it is out of use. It also does not allow the counters to 1467d1c3fb1fSNishanth Aravamudan * go out of whack in adjust_pool_surplus() as we don't modify 1468d1c3fb1fSNishanth Aravamudan * the node values until we've gotten the hugepage and only the 1469d1c3fb1fSNishanth Aravamudan * per-node value is checked there. 1470d1c3fb1fSNishanth Aravamudan */ 1471d1c3fb1fSNishanth Aravamudan spin_lock(&hugetlb_lock); 1472a5516438SAndi Kleen if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) { 1473d1c3fb1fSNishanth Aravamudan spin_unlock(&hugetlb_lock); 1474d1c3fb1fSNishanth Aravamudan return NULL; 1475d1c3fb1fSNishanth Aravamudan } else { 1476a5516438SAndi Kleen h->nr_huge_pages++; 1477a5516438SAndi Kleen h->surplus_huge_pages++; 1478d1c3fb1fSNishanth Aravamudan } 1479d1c3fb1fSNishanth Aravamudan spin_unlock(&hugetlb_lock); 1480d1c3fb1fSNishanth Aravamudan 1481bf50bab2SNaoya Horiguchi if (nid == NUMA_NO_NODE) 148286cdb465SNaoya Horiguchi page = alloc_pages(htlb_alloc_mask(h)|__GFP_COMP| 1483551883aeSNishanth Aravamudan __GFP_REPEAT|__GFP_NOWARN, 1484a5516438SAndi Kleen huge_page_order(h)); 1485bf50bab2SNaoya Horiguchi else 148696db800fSVlastimil Babka page = __alloc_pages_node(nid, 148786cdb465SNaoya Horiguchi htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE| 1488bf50bab2SNaoya Horiguchi __GFP_REPEAT|__GFP_NOWARN, huge_page_order(h)); 1489d1c3fb1fSNishanth Aravamudan 14907893d1d5SAdam Litke spin_lock(&hugetlb_lock); 1491d1c3fb1fSNishanth Aravamudan if (page) { 14920edaecfaSAneesh Kumar K.V INIT_LIST_HEAD(&page->lru); 1493bf50bab2SNaoya Horiguchi r_nid = page_to_nid(page); 1494d1c3fb1fSNishanth Aravamudan set_compound_page_dtor(page, free_huge_page); 14959dd540e2SAneesh Kumar K.V set_hugetlb_cgroup(page, NULL); 1496d1c3fb1fSNishanth Aravamudan /* 1497d1c3fb1fSNishanth Aravamudan * We incremented the global counters already 1498d1c3fb1fSNishanth Aravamudan */ 1499bf50bab2SNaoya Horiguchi h->nr_huge_pages_node[r_nid]++; 1500bf50bab2SNaoya Horiguchi h->surplus_huge_pages_node[r_nid]++; 15013b116300SAdam Litke __count_vm_event(HTLB_BUDDY_PGALLOC); 1502d1c3fb1fSNishanth Aravamudan } else { 1503a5516438SAndi Kleen h->nr_huge_pages--; 1504a5516438SAndi Kleen h->surplus_huge_pages--; 15053b116300SAdam Litke __count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); 15067893d1d5SAdam Litke } 1507d1c3fb1fSNishanth Aravamudan spin_unlock(&hugetlb_lock); 15087893d1d5SAdam Litke 15097893d1d5SAdam Litke return page; 15107893d1d5SAdam Litke } 15117893d1d5SAdam Litke 1512e4e574b7SAdam Litke /* 1513bf50bab2SNaoya Horiguchi * This allocation function is useful in the context where vma is irrelevant. 1514bf50bab2SNaoya Horiguchi * E.g. soft-offlining uses this function because it only cares physical 1515bf50bab2SNaoya Horiguchi * address of error page. 1516bf50bab2SNaoya Horiguchi */ 1517bf50bab2SNaoya Horiguchi struct page *alloc_huge_page_node(struct hstate *h, int nid) 1518bf50bab2SNaoya Horiguchi { 15194ef91848SJoonsoo Kim struct page *page = NULL; 1520bf50bab2SNaoya Horiguchi 1521bf50bab2SNaoya Horiguchi spin_lock(&hugetlb_lock); 15224ef91848SJoonsoo Kim if (h->free_huge_pages - h->resv_huge_pages > 0) 1523bf50bab2SNaoya Horiguchi page = dequeue_huge_page_node(h, nid); 1524bf50bab2SNaoya Horiguchi spin_unlock(&hugetlb_lock); 1525bf50bab2SNaoya Horiguchi 152694ae8ba7SAneesh Kumar K.V if (!page) 1527bf50bab2SNaoya Horiguchi page = alloc_buddy_huge_page(h, nid); 1528bf50bab2SNaoya Horiguchi 1529bf50bab2SNaoya Horiguchi return page; 1530bf50bab2SNaoya Horiguchi } 1531bf50bab2SNaoya Horiguchi 1532bf50bab2SNaoya Horiguchi /* 153325985edcSLucas De Marchi * Increase the hugetlb pool such that it can accommodate a reservation 1534e4e574b7SAdam Litke * of size 'delta'. 1535e4e574b7SAdam Litke */ 1536a5516438SAndi Kleen static int gather_surplus_pages(struct hstate *h, int delta) 1537e4e574b7SAdam Litke { 1538e4e574b7SAdam Litke struct list_head surplus_list; 1539e4e574b7SAdam Litke struct page *page, *tmp; 1540e4e574b7SAdam Litke int ret, i; 1541e4e574b7SAdam Litke int needed, allocated; 154228073b02SHillf Danton bool alloc_ok = true; 1543e4e574b7SAdam Litke 1544a5516438SAndi Kleen needed = (h->resv_huge_pages + delta) - h->free_huge_pages; 1545ac09b3a1SAdam Litke if (needed <= 0) { 1546a5516438SAndi Kleen h->resv_huge_pages += delta; 1547e4e574b7SAdam Litke return 0; 1548ac09b3a1SAdam Litke } 1549e4e574b7SAdam Litke 1550e4e574b7SAdam Litke allocated = 0; 1551e4e574b7SAdam Litke INIT_LIST_HEAD(&surplus_list); 1552e4e574b7SAdam Litke 1553e4e574b7SAdam Litke ret = -ENOMEM; 1554e4e574b7SAdam Litke retry: 1555e4e574b7SAdam Litke spin_unlock(&hugetlb_lock); 1556e4e574b7SAdam Litke for (i = 0; i < needed; i++) { 1557bf50bab2SNaoya Horiguchi page = alloc_buddy_huge_page(h, NUMA_NO_NODE); 155828073b02SHillf Danton if (!page) { 155928073b02SHillf Danton alloc_ok = false; 156028073b02SHillf Danton break; 156128073b02SHillf Danton } 1562e4e574b7SAdam Litke list_add(&page->lru, &surplus_list); 1563e4e574b7SAdam Litke } 156428073b02SHillf Danton allocated += i; 1565e4e574b7SAdam Litke 1566e4e574b7SAdam Litke /* 1567e4e574b7SAdam Litke * After retaking hugetlb_lock, we need to recalculate 'needed' 1568e4e574b7SAdam Litke * because either resv_huge_pages or free_huge_pages may have changed. 1569e4e574b7SAdam Litke */ 1570e4e574b7SAdam Litke spin_lock(&hugetlb_lock); 1571a5516438SAndi Kleen needed = (h->resv_huge_pages + delta) - 1572a5516438SAndi Kleen (h->free_huge_pages + allocated); 157328073b02SHillf Danton if (needed > 0) { 157428073b02SHillf Danton if (alloc_ok) 1575e4e574b7SAdam Litke goto retry; 157628073b02SHillf Danton /* 157728073b02SHillf Danton * We were not able to allocate enough pages to 157828073b02SHillf Danton * satisfy the entire reservation so we free what 157928073b02SHillf Danton * we've allocated so far. 158028073b02SHillf Danton */ 158128073b02SHillf Danton goto free; 158228073b02SHillf Danton } 1583e4e574b7SAdam Litke /* 1584e4e574b7SAdam Litke * The surplus_list now contains _at_least_ the number of extra pages 158525985edcSLucas De Marchi * needed to accommodate the reservation. Add the appropriate number 1586e4e574b7SAdam Litke * of pages to the hugetlb pool and free the extras back to the buddy 1587ac09b3a1SAdam Litke * allocator. Commit the entire reservation here to prevent another 1588ac09b3a1SAdam Litke * process from stealing the pages as they are added to the pool but 1589ac09b3a1SAdam Litke * before they are reserved. 1590e4e574b7SAdam Litke */ 1591e4e574b7SAdam Litke needed += allocated; 1592a5516438SAndi Kleen h->resv_huge_pages += delta; 1593e4e574b7SAdam Litke ret = 0; 1594a9869b83SNaoya Horiguchi 159519fc3f0aSAdam Litke /* Free the needed pages to the hugetlb pool */ 159619fc3f0aSAdam Litke list_for_each_entry_safe(page, tmp, &surplus_list, lru) { 159719fc3f0aSAdam Litke if ((--needed) < 0) 159819fc3f0aSAdam Litke break; 1599a9869b83SNaoya Horiguchi /* 1600a9869b83SNaoya Horiguchi * This page is now managed by the hugetlb allocator and has 1601a9869b83SNaoya Horiguchi * no users -- drop the buddy allocator's reference. 1602a9869b83SNaoya Horiguchi */ 1603a9869b83SNaoya Horiguchi put_page_testzero(page); 1604309381feSSasha Levin VM_BUG_ON_PAGE(page_count(page), page); 1605a5516438SAndi Kleen enqueue_huge_page(h, page); 160619fc3f0aSAdam Litke } 160728073b02SHillf Danton free: 1608b0365c8dSHillf Danton spin_unlock(&hugetlb_lock); 160919fc3f0aSAdam Litke 161019fc3f0aSAdam Litke /* Free unnecessary surplus pages to the buddy allocator */ 1611c0d934baSJoonsoo Kim list_for_each_entry_safe(page, tmp, &surplus_list, lru) 1612a9869b83SNaoya Horiguchi put_page(page); 161319fc3f0aSAdam Litke spin_lock(&hugetlb_lock); 1614e4e574b7SAdam Litke 1615e4e574b7SAdam Litke return ret; 1616e4e574b7SAdam Litke } 1617e4e574b7SAdam Litke 1618e4e574b7SAdam Litke /* 1619e4e574b7SAdam Litke * When releasing a hugetlb pool reservation, any surplus pages that were 1620e4e574b7SAdam Litke * allocated to satisfy the reservation must be explicitly freed if they were 1621e4e574b7SAdam Litke * never used. 1622685f3457SLee Schermerhorn * Called with hugetlb_lock held. 1623e4e574b7SAdam Litke */ 1624a5516438SAndi Kleen static void return_unused_surplus_pages(struct hstate *h, 1625a5516438SAndi Kleen unsigned long unused_resv_pages) 1626e4e574b7SAdam Litke { 1627e4e574b7SAdam Litke unsigned long nr_pages; 1628e4e574b7SAdam Litke 1629ac09b3a1SAdam Litke /* Uncommit the reservation */ 1630a5516438SAndi Kleen h->resv_huge_pages -= unused_resv_pages; 1631ac09b3a1SAdam Litke 1632aa888a74SAndi Kleen /* Cannot return gigantic pages currently */ 1633bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 1634aa888a74SAndi Kleen return; 1635aa888a74SAndi Kleen 1636a5516438SAndi Kleen nr_pages = min(unused_resv_pages, h->surplus_huge_pages); 1637e4e574b7SAdam Litke 1638685f3457SLee Schermerhorn /* 1639685f3457SLee Schermerhorn * We want to release as many surplus pages as possible, spread 16409b5e5d0fSLee Schermerhorn * evenly across all nodes with memory. Iterate across these nodes 16419b5e5d0fSLee Schermerhorn * until we can no longer free unreserved surplus pages. This occurs 16429b5e5d0fSLee Schermerhorn * when the nodes with surplus pages have no free pages. 16439b5e5d0fSLee Schermerhorn * free_pool_huge_page() will balance the the freed pages across the 16449b5e5d0fSLee Schermerhorn * on-line nodes with memory and will handle the hstate accounting. 1645685f3457SLee Schermerhorn */ 1646685f3457SLee Schermerhorn while (nr_pages--) { 16478cebfcd0SLai Jiangshan if (!free_pool_huge_page(h, &node_states[N_MEMORY], 1)) 1648685f3457SLee Schermerhorn break; 16497848a4bfSMizuma, Masayoshi cond_resched_lock(&hugetlb_lock); 1650e4e574b7SAdam Litke } 1651e4e574b7SAdam Litke } 1652e4e574b7SAdam Litke 16535e911373SMike Kravetz 1654c37f9fb1SAndy Whitcroft /* 1655feba16e2SMike Kravetz * vma_needs_reservation, vma_commit_reservation and vma_end_reservation 16565e911373SMike Kravetz * are used by the huge page allocation routines to manage reservations. 1657cf3ad20bSMike Kravetz * 1658cf3ad20bSMike Kravetz * vma_needs_reservation is called to determine if the huge page at addr 1659cf3ad20bSMike Kravetz * within the vma has an associated reservation. If a reservation is 1660cf3ad20bSMike Kravetz * needed, the value 1 is returned. The caller is then responsible for 1661cf3ad20bSMike Kravetz * managing the global reservation and subpool usage counts. After 1662cf3ad20bSMike Kravetz * the huge page has been allocated, vma_commit_reservation is called 1663feba16e2SMike Kravetz * to add the page to the reservation map. If the page allocation fails, 1664feba16e2SMike Kravetz * the reservation must be ended instead of committed. vma_end_reservation 1665feba16e2SMike Kravetz * is called in such cases. 1666cf3ad20bSMike Kravetz * 1667cf3ad20bSMike Kravetz * In the normal case, vma_commit_reservation returns the same value 1668cf3ad20bSMike Kravetz * as the preceding vma_needs_reservation call. The only time this 1669cf3ad20bSMike Kravetz * is not the case is if a reserve map was changed between calls. It 1670cf3ad20bSMike Kravetz * is the responsibility of the caller to notice the difference and 1671cf3ad20bSMike Kravetz * take appropriate action. 1672c37f9fb1SAndy Whitcroft */ 16735e911373SMike Kravetz enum vma_resv_mode { 16745e911373SMike Kravetz VMA_NEEDS_RESV, 16755e911373SMike Kravetz VMA_COMMIT_RESV, 1676feba16e2SMike Kravetz VMA_END_RESV, 16775e911373SMike Kravetz }; 1678cf3ad20bSMike Kravetz static long __vma_reservation_common(struct hstate *h, 1679cf3ad20bSMike Kravetz struct vm_area_struct *vma, unsigned long addr, 16805e911373SMike Kravetz enum vma_resv_mode mode) 1681c37f9fb1SAndy Whitcroft { 16824e35f483SJoonsoo Kim struct resv_map *resv; 16834e35f483SJoonsoo Kim pgoff_t idx; 1684cf3ad20bSMike Kravetz long ret; 1685c37f9fb1SAndy Whitcroft 16864e35f483SJoonsoo Kim resv = vma_resv_map(vma); 16874e35f483SJoonsoo Kim if (!resv) 1688c37f9fb1SAndy Whitcroft return 1; 1689c37f9fb1SAndy Whitcroft 16904e35f483SJoonsoo Kim idx = vma_hugecache_offset(h, vma, addr); 16915e911373SMike Kravetz switch (mode) { 16925e911373SMike Kravetz case VMA_NEEDS_RESV: 1693cf3ad20bSMike Kravetz ret = region_chg(resv, idx, idx + 1); 16945e911373SMike Kravetz break; 16955e911373SMike Kravetz case VMA_COMMIT_RESV: 16965e911373SMike Kravetz ret = region_add(resv, idx, idx + 1); 16975e911373SMike Kravetz break; 1698feba16e2SMike Kravetz case VMA_END_RESV: 16995e911373SMike Kravetz region_abort(resv, idx, idx + 1); 17005e911373SMike Kravetz ret = 0; 17015e911373SMike Kravetz break; 17025e911373SMike Kravetz default: 17035e911373SMike Kravetz BUG(); 17045e911373SMike Kravetz } 170584afd99bSAndy Whitcroft 17064e35f483SJoonsoo Kim if (vma->vm_flags & VM_MAYSHARE) 1707cf3ad20bSMike Kravetz return ret; 17084e35f483SJoonsoo Kim else 1709cf3ad20bSMike Kravetz return ret < 0 ? ret : 0; 171084afd99bSAndy Whitcroft } 1711cf3ad20bSMike Kravetz 1712cf3ad20bSMike Kravetz static long vma_needs_reservation(struct hstate *h, 1713a5516438SAndi Kleen struct vm_area_struct *vma, unsigned long addr) 1714c37f9fb1SAndy Whitcroft { 17155e911373SMike Kravetz return __vma_reservation_common(h, vma, addr, VMA_NEEDS_RESV); 1716cf3ad20bSMike Kravetz } 1717c37f9fb1SAndy Whitcroft 1718cf3ad20bSMike Kravetz static long vma_commit_reservation(struct hstate *h, 1719cf3ad20bSMike Kravetz struct vm_area_struct *vma, unsigned long addr) 1720cf3ad20bSMike Kravetz { 17215e911373SMike Kravetz return __vma_reservation_common(h, vma, addr, VMA_COMMIT_RESV); 17225e911373SMike Kravetz } 17235e911373SMike Kravetz 1724feba16e2SMike Kravetz static void vma_end_reservation(struct hstate *h, 17255e911373SMike Kravetz struct vm_area_struct *vma, unsigned long addr) 17265e911373SMike Kravetz { 1727feba16e2SMike Kravetz (void)__vma_reservation_common(h, vma, addr, VMA_END_RESV); 1728c37f9fb1SAndy Whitcroft } 1729c37f9fb1SAndy Whitcroft 173070c3547eSMike Kravetz struct page *alloc_huge_page(struct vm_area_struct *vma, 173104f2cbe3SMel Gorman unsigned long addr, int avoid_reserve) 1732348ea204SAdam Litke { 173390481622SDavid Gibson struct hugepage_subpool *spool = subpool_vma(vma); 1734a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 1735348ea204SAdam Litke struct page *page; 1736d85f69b0SMike Kravetz long map_chg, map_commit; 1737d85f69b0SMike Kravetz long gbl_chg; 17386d76dcf4SAneesh Kumar K.V int ret, idx; 17396d76dcf4SAneesh Kumar K.V struct hugetlb_cgroup *h_cg; 17402fc39cecSAdam Litke 17416d76dcf4SAneesh Kumar K.V idx = hstate_index(h); 1742a1e78772SMel Gorman /* 1743d85f69b0SMike Kravetz * Examine the region/reserve map to determine if the process 1744d85f69b0SMike Kravetz * has a reservation for the page to be allocated. A return 1745d85f69b0SMike Kravetz * code of zero indicates a reservation exists (no change). 1746a1e78772SMel Gorman */ 1747d85f69b0SMike Kravetz map_chg = gbl_chg = vma_needs_reservation(h, vma, addr); 1748d85f69b0SMike Kravetz if (map_chg < 0) 174976dcee75SAneesh Kumar K.V return ERR_PTR(-ENOMEM); 1750d85f69b0SMike Kravetz 1751d85f69b0SMike Kravetz /* 1752d85f69b0SMike Kravetz * Processes that did not create the mapping will have no 1753d85f69b0SMike Kravetz * reserves as indicated by the region/reserve map. Check 1754d85f69b0SMike Kravetz * that the allocation will not exceed the subpool limit. 1755d85f69b0SMike Kravetz * Allocations for MAP_NORESERVE mappings also need to be 1756d85f69b0SMike Kravetz * checked against any subpool limit. 1757d85f69b0SMike Kravetz */ 1758d85f69b0SMike Kravetz if (map_chg || avoid_reserve) { 1759d85f69b0SMike Kravetz gbl_chg = hugepage_subpool_get_pages(spool, 1); 1760d85f69b0SMike Kravetz if (gbl_chg < 0) { 1761feba16e2SMike Kravetz vma_end_reservation(h, vma, addr); 176276dcee75SAneesh Kumar K.V return ERR_PTR(-ENOSPC); 17635e911373SMike Kravetz } 176490d8b7e6SAdam Litke 1765d85f69b0SMike Kravetz /* 1766d85f69b0SMike Kravetz * Even though there was no reservation in the region/reserve 1767d85f69b0SMike Kravetz * map, there could be reservations associated with the 1768d85f69b0SMike Kravetz * subpool that can be used. This would be indicated if the 1769d85f69b0SMike Kravetz * return value of hugepage_subpool_get_pages() is zero. 1770d85f69b0SMike Kravetz * However, if avoid_reserve is specified we still avoid even 1771d85f69b0SMike Kravetz * the subpool reservations. 1772d85f69b0SMike Kravetz */ 1773d85f69b0SMike Kravetz if (avoid_reserve) 1774d85f69b0SMike Kravetz gbl_chg = 1; 1775d85f69b0SMike Kravetz } 1776d85f69b0SMike Kravetz 17776d76dcf4SAneesh Kumar K.V ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg); 17788f34af6fSJianyu Zhan if (ret) 17798f34af6fSJianyu Zhan goto out_subpool_put; 17808f34af6fSJianyu Zhan 1781a1e78772SMel Gorman spin_lock(&hugetlb_lock); 1782d85f69b0SMike Kravetz /* 1783d85f69b0SMike Kravetz * glb_chg is passed to indicate whether or not a page must be taken 1784d85f69b0SMike Kravetz * from the global free pool (global change). gbl_chg == 0 indicates 1785d85f69b0SMike Kravetz * a reservation exists for the allocation. 1786d85f69b0SMike Kravetz */ 1787d85f69b0SMike Kravetz page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, gbl_chg); 178881a6fcaeSJoonsoo Kim if (!page) { 178994ae8ba7SAneesh Kumar K.V spin_unlock(&hugetlb_lock); 1790bf50bab2SNaoya Horiguchi page = alloc_buddy_huge_page(h, NUMA_NO_NODE); 17918f34af6fSJianyu Zhan if (!page) 17928f34af6fSJianyu Zhan goto out_uncharge_cgroup; 17938f34af6fSJianyu Zhan 179479dbb236SAneesh Kumar K.V spin_lock(&hugetlb_lock); 179579dbb236SAneesh Kumar K.V list_move(&page->lru, &h->hugepage_activelist); 179681a6fcaeSJoonsoo Kim /* Fall through */ 1797a1e78772SMel Gorman } 179881a6fcaeSJoonsoo Kim hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, page); 179981a6fcaeSJoonsoo Kim spin_unlock(&hugetlb_lock); 1800a1e78772SMel Gorman 180190481622SDavid Gibson set_page_private(page, (unsigned long)spool); 1802a1e78772SMel Gorman 1803d85f69b0SMike Kravetz map_commit = vma_commit_reservation(h, vma, addr); 1804d85f69b0SMike Kravetz if (unlikely(map_chg > map_commit)) { 180533039678SMike Kravetz /* 180633039678SMike Kravetz * The page was added to the reservation map between 180733039678SMike Kravetz * vma_needs_reservation and vma_commit_reservation. 180833039678SMike Kravetz * This indicates a race with hugetlb_reserve_pages. 180933039678SMike Kravetz * Adjust for the subpool count incremented above AND 181033039678SMike Kravetz * in hugetlb_reserve_pages for the same page. Also, 181133039678SMike Kravetz * the reservation count added in hugetlb_reserve_pages 181233039678SMike Kravetz * no longer applies. 181333039678SMike Kravetz */ 181433039678SMike Kravetz long rsv_adjust; 181533039678SMike Kravetz 181633039678SMike Kravetz rsv_adjust = hugepage_subpool_put_pages(spool, 1); 181733039678SMike Kravetz hugetlb_acct_memory(h, -rsv_adjust); 181833039678SMike Kravetz } 18197893d1d5SAdam Litke return page; 18208f34af6fSJianyu Zhan 18218f34af6fSJianyu Zhan out_uncharge_cgroup: 18228f34af6fSJianyu Zhan hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg); 18238f34af6fSJianyu Zhan out_subpool_put: 1824d85f69b0SMike Kravetz if (map_chg || avoid_reserve) 18258f34af6fSJianyu Zhan hugepage_subpool_put_pages(spool, 1); 1826feba16e2SMike Kravetz vma_end_reservation(h, vma, addr); 18278f34af6fSJianyu Zhan return ERR_PTR(-ENOSPC); 1828b45b5bd6SDavid Gibson } 1829b45b5bd6SDavid Gibson 183074060e4dSNaoya Horiguchi /* 183174060e4dSNaoya Horiguchi * alloc_huge_page()'s wrapper which simply returns the page if allocation 183274060e4dSNaoya Horiguchi * succeeds, otherwise NULL. This function is called from new_vma_page(), 183374060e4dSNaoya Horiguchi * where no ERR_VALUE is expected to be returned. 183474060e4dSNaoya Horiguchi */ 183574060e4dSNaoya Horiguchi struct page *alloc_huge_page_noerr(struct vm_area_struct *vma, 183674060e4dSNaoya Horiguchi unsigned long addr, int avoid_reserve) 183774060e4dSNaoya Horiguchi { 183874060e4dSNaoya Horiguchi struct page *page = alloc_huge_page(vma, addr, avoid_reserve); 183974060e4dSNaoya Horiguchi if (IS_ERR(page)) 184074060e4dSNaoya Horiguchi page = NULL; 184174060e4dSNaoya Horiguchi return page; 184274060e4dSNaoya Horiguchi } 184374060e4dSNaoya Horiguchi 184491f47662SCyrill Gorcunov int __weak alloc_bootmem_huge_page(struct hstate *h) 1845aa888a74SAndi Kleen { 1846aa888a74SAndi Kleen struct huge_bootmem_page *m; 1847b2261026SJoonsoo Kim int nr_nodes, node; 1848aa888a74SAndi Kleen 1849b2261026SJoonsoo Kim for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) { 1850aa888a74SAndi Kleen void *addr; 1851aa888a74SAndi Kleen 18528b89a116SGrygorii Strashko addr = memblock_virt_alloc_try_nid_nopanic( 18538b89a116SGrygorii Strashko huge_page_size(h), huge_page_size(h), 18548b89a116SGrygorii Strashko 0, BOOTMEM_ALLOC_ACCESSIBLE, node); 1855aa888a74SAndi Kleen if (addr) { 1856aa888a74SAndi Kleen /* 1857aa888a74SAndi Kleen * Use the beginning of the huge page to store the 1858aa888a74SAndi Kleen * huge_bootmem_page struct (until gather_bootmem 1859aa888a74SAndi Kleen * puts them into the mem_map). 1860aa888a74SAndi Kleen */ 1861aa888a74SAndi Kleen m = addr; 1862aa888a74SAndi Kleen goto found; 1863aa888a74SAndi Kleen } 1864aa888a74SAndi Kleen } 1865aa888a74SAndi Kleen return 0; 1866aa888a74SAndi Kleen 1867aa888a74SAndi Kleen found: 1868df994eadSLuiz Capitulino BUG_ON(!IS_ALIGNED(virt_to_phys(m), huge_page_size(h))); 1869aa888a74SAndi Kleen /* Put them into a private list first because mem_map is not up yet */ 1870aa888a74SAndi Kleen list_add(&m->list, &huge_boot_pages); 1871aa888a74SAndi Kleen m->hstate = h; 1872aa888a74SAndi Kleen return 1; 1873aa888a74SAndi Kleen } 1874aa888a74SAndi Kleen 1875f412c97aSDavid Rientjes static void __init prep_compound_huge_page(struct page *page, int order) 187618229df5SAndy Whitcroft { 187718229df5SAndy Whitcroft if (unlikely(order > (MAX_ORDER - 1))) 187818229df5SAndy Whitcroft prep_compound_gigantic_page(page, order); 187918229df5SAndy Whitcroft else 188018229df5SAndy Whitcroft prep_compound_page(page, order); 188118229df5SAndy Whitcroft } 188218229df5SAndy Whitcroft 1883aa888a74SAndi Kleen /* Put bootmem huge pages into the standard lists after mem_map is up */ 1884aa888a74SAndi Kleen static void __init gather_bootmem_prealloc(void) 1885aa888a74SAndi Kleen { 1886aa888a74SAndi Kleen struct huge_bootmem_page *m; 1887aa888a74SAndi Kleen 1888aa888a74SAndi Kleen list_for_each_entry(m, &huge_boot_pages, list) { 1889aa888a74SAndi Kleen struct hstate *h = m->hstate; 1890ee8f248dSBecky Bruce struct page *page; 1891ee8f248dSBecky Bruce 1892ee8f248dSBecky Bruce #ifdef CONFIG_HIGHMEM 1893ee8f248dSBecky Bruce page = pfn_to_page(m->phys >> PAGE_SHIFT); 18948b89a116SGrygorii Strashko memblock_free_late(__pa(m), 1895ee8f248dSBecky Bruce sizeof(struct huge_bootmem_page)); 1896ee8f248dSBecky Bruce #else 1897ee8f248dSBecky Bruce page = virt_to_page(m); 1898ee8f248dSBecky Bruce #endif 1899aa888a74SAndi Kleen WARN_ON(page_count(page) != 1); 190018229df5SAndy Whitcroft prep_compound_huge_page(page, h->order); 1901ef5a22beSAndrea Arcangeli WARN_ON(PageReserved(page)); 1902aa888a74SAndi Kleen prep_new_huge_page(h, page, page_to_nid(page)); 1903b0320c7bSRafael Aquini /* 1904b0320c7bSRafael Aquini * If we had gigantic hugepages allocated at boot time, we need 1905b0320c7bSRafael Aquini * to restore the 'stolen' pages to totalram_pages in order to 1906b0320c7bSRafael Aquini * fix confusing memory reports from free(1) and another 1907b0320c7bSRafael Aquini * side-effects, like CommitLimit going negative. 1908b0320c7bSRafael Aquini */ 1909bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 19103dcc0571SJiang Liu adjust_managed_page_count(page, 1 << h->order); 1911aa888a74SAndi Kleen } 1912aa888a74SAndi Kleen } 1913aa888a74SAndi Kleen 19148faa8b07SAndi Kleen static void __init hugetlb_hstate_alloc_pages(struct hstate *h) 19151da177e4SLinus Torvalds { 19161da177e4SLinus Torvalds unsigned long i; 19171da177e4SLinus Torvalds 1918e5ff2159SAndi Kleen for (i = 0; i < h->max_huge_pages; ++i) { 1919bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) { 1920aa888a74SAndi Kleen if (!alloc_bootmem_huge_page(h)) 1921aa888a74SAndi Kleen break; 19229b5e5d0fSLee Schermerhorn } else if (!alloc_fresh_huge_page(h, 19238cebfcd0SLai Jiangshan &node_states[N_MEMORY])) 19241da177e4SLinus Torvalds break; 19251da177e4SLinus Torvalds } 19268faa8b07SAndi Kleen h->max_huge_pages = i; 1927e5ff2159SAndi Kleen } 1928e5ff2159SAndi Kleen 1929e5ff2159SAndi Kleen static void __init hugetlb_init_hstates(void) 1930e5ff2159SAndi Kleen { 1931e5ff2159SAndi Kleen struct hstate *h; 1932e5ff2159SAndi Kleen 1933e5ff2159SAndi Kleen for_each_hstate(h) { 1934641844f5SNaoya Horiguchi if (minimum_order > huge_page_order(h)) 1935641844f5SNaoya Horiguchi minimum_order = huge_page_order(h); 1936641844f5SNaoya Horiguchi 19378faa8b07SAndi Kleen /* oversize hugepages were init'ed in early boot */ 1938bae7f4aeSLuiz Capitulino if (!hstate_is_gigantic(h)) 19398faa8b07SAndi Kleen hugetlb_hstate_alloc_pages(h); 1940e5ff2159SAndi Kleen } 1941641844f5SNaoya Horiguchi VM_BUG_ON(minimum_order == UINT_MAX); 1942e5ff2159SAndi Kleen } 1943e5ff2159SAndi Kleen 19444abd32dbSAndi Kleen static char * __init memfmt(char *buf, unsigned long n) 19454abd32dbSAndi Kleen { 19464abd32dbSAndi Kleen if (n >= (1UL << 30)) 19474abd32dbSAndi Kleen sprintf(buf, "%lu GB", n >> 30); 19484abd32dbSAndi Kleen else if (n >= (1UL << 20)) 19494abd32dbSAndi Kleen sprintf(buf, "%lu MB", n >> 20); 19504abd32dbSAndi Kleen else 19514abd32dbSAndi Kleen sprintf(buf, "%lu KB", n >> 10); 19524abd32dbSAndi Kleen return buf; 19534abd32dbSAndi Kleen } 19544abd32dbSAndi Kleen 1955e5ff2159SAndi Kleen static void __init report_hugepages(void) 1956e5ff2159SAndi Kleen { 1957e5ff2159SAndi Kleen struct hstate *h; 1958e5ff2159SAndi Kleen 1959e5ff2159SAndi Kleen for_each_hstate(h) { 19604abd32dbSAndi Kleen char buf[32]; 1961ffb22af5SAndrew Morton pr_info("HugeTLB registered %s page size, pre-allocated %ld pages\n", 19624abd32dbSAndi Kleen memfmt(buf, huge_page_size(h)), 19634abd32dbSAndi Kleen h->free_huge_pages); 1964e5ff2159SAndi Kleen } 1965e5ff2159SAndi Kleen } 1966e5ff2159SAndi Kleen 19671da177e4SLinus Torvalds #ifdef CONFIG_HIGHMEM 19686ae11b27SLee Schermerhorn static void try_to_free_low(struct hstate *h, unsigned long count, 19696ae11b27SLee Schermerhorn nodemask_t *nodes_allowed) 19701da177e4SLinus Torvalds { 19714415cc8dSChristoph Lameter int i; 19724415cc8dSChristoph Lameter 1973bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 1974aa888a74SAndi Kleen return; 1975aa888a74SAndi Kleen 19766ae11b27SLee Schermerhorn for_each_node_mask(i, *nodes_allowed) { 19771da177e4SLinus Torvalds struct page *page, *next; 1978a5516438SAndi Kleen struct list_head *freel = &h->hugepage_freelists[i]; 1979a5516438SAndi Kleen list_for_each_entry_safe(page, next, freel, lru) { 1980a5516438SAndi Kleen if (count >= h->nr_huge_pages) 19816b0c880dSAdam Litke return; 19821da177e4SLinus Torvalds if (PageHighMem(page)) 19831da177e4SLinus Torvalds continue; 19841da177e4SLinus Torvalds list_del(&page->lru); 1985e5ff2159SAndi Kleen update_and_free_page(h, page); 1986a5516438SAndi Kleen h->free_huge_pages--; 1987a5516438SAndi Kleen h->free_huge_pages_node[page_to_nid(page)]--; 19881da177e4SLinus Torvalds } 19891da177e4SLinus Torvalds } 19901da177e4SLinus Torvalds } 19911da177e4SLinus Torvalds #else 19926ae11b27SLee Schermerhorn static inline void try_to_free_low(struct hstate *h, unsigned long count, 19936ae11b27SLee Schermerhorn nodemask_t *nodes_allowed) 19941da177e4SLinus Torvalds { 19951da177e4SLinus Torvalds } 19961da177e4SLinus Torvalds #endif 19971da177e4SLinus Torvalds 199820a0307cSWu Fengguang /* 199920a0307cSWu Fengguang * Increment or decrement surplus_huge_pages. Keep node-specific counters 200020a0307cSWu Fengguang * balanced by operating on them in a round-robin fashion. 200120a0307cSWu Fengguang * Returns 1 if an adjustment was made. 200220a0307cSWu Fengguang */ 20036ae11b27SLee Schermerhorn static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, 20046ae11b27SLee Schermerhorn int delta) 200520a0307cSWu Fengguang { 2006b2261026SJoonsoo Kim int nr_nodes, node; 200720a0307cSWu Fengguang 200820a0307cSWu Fengguang VM_BUG_ON(delta != -1 && delta != 1); 200920a0307cSWu Fengguang 2010e8c5c824SLee Schermerhorn if (delta < 0) { 2011b2261026SJoonsoo Kim for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { 2012b2261026SJoonsoo Kim if (h->surplus_huge_pages_node[node]) 2013b2261026SJoonsoo Kim goto found; 2014b2261026SJoonsoo Kim } 2015b2261026SJoonsoo Kim } else { 2016b2261026SJoonsoo Kim for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { 2017b2261026SJoonsoo Kim if (h->surplus_huge_pages_node[node] < 2018b2261026SJoonsoo Kim h->nr_huge_pages_node[node]) 2019b2261026SJoonsoo Kim goto found; 2020e8c5c824SLee Schermerhorn } 20219a76db09SLee Schermerhorn } 2022b2261026SJoonsoo Kim return 0; 202320a0307cSWu Fengguang 2024b2261026SJoonsoo Kim found: 202520a0307cSWu Fengguang h->surplus_huge_pages += delta; 2026b2261026SJoonsoo Kim h->surplus_huge_pages_node[node] += delta; 2027b2261026SJoonsoo Kim return 1; 202820a0307cSWu Fengguang } 202920a0307cSWu Fengguang 2030a5516438SAndi Kleen #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) 20316ae11b27SLee Schermerhorn static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count, 20326ae11b27SLee Schermerhorn nodemask_t *nodes_allowed) 20331da177e4SLinus Torvalds { 20347893d1d5SAdam Litke unsigned long min_count, ret; 20351da177e4SLinus Torvalds 2036944d9fecSLuiz Capitulino if (hstate_is_gigantic(h) && !gigantic_page_supported()) 2037aa888a74SAndi Kleen return h->max_huge_pages; 2038aa888a74SAndi Kleen 20397893d1d5SAdam Litke /* 20407893d1d5SAdam Litke * Increase the pool size 20417893d1d5SAdam Litke * First take pages out of surplus state. Then make up the 20427893d1d5SAdam Litke * remaining difference by allocating fresh huge pages. 2043d1c3fb1fSNishanth Aravamudan * 2044d1c3fb1fSNishanth Aravamudan * We might race with alloc_buddy_huge_page() here and be unable 2045d1c3fb1fSNishanth Aravamudan * to convert a surplus huge page to a normal huge page. That is 2046d1c3fb1fSNishanth Aravamudan * not critical, though, it just means the overall size of the 2047d1c3fb1fSNishanth Aravamudan * pool might be one hugepage larger than it needs to be, but 2048d1c3fb1fSNishanth Aravamudan * within all the constraints specified by the sysctls. 20497893d1d5SAdam Litke */ 20501da177e4SLinus Torvalds spin_lock(&hugetlb_lock); 2051a5516438SAndi Kleen while (h->surplus_huge_pages && count > persistent_huge_pages(h)) { 20526ae11b27SLee Schermerhorn if (!adjust_pool_surplus(h, nodes_allowed, -1)) 20537893d1d5SAdam Litke break; 20547893d1d5SAdam Litke } 20557893d1d5SAdam Litke 2056a5516438SAndi Kleen while (count > persistent_huge_pages(h)) { 20577893d1d5SAdam Litke /* 20587893d1d5SAdam Litke * If this allocation races such that we no longer need the 20597893d1d5SAdam Litke * page, free_huge_page will handle it by freeing the page 20607893d1d5SAdam Litke * and reducing the surplus. 20617893d1d5SAdam Litke */ 20627893d1d5SAdam Litke spin_unlock(&hugetlb_lock); 2063944d9fecSLuiz Capitulino if (hstate_is_gigantic(h)) 2064944d9fecSLuiz Capitulino ret = alloc_fresh_gigantic_page(h, nodes_allowed); 2065944d9fecSLuiz Capitulino else 20666ae11b27SLee Schermerhorn ret = alloc_fresh_huge_page(h, nodes_allowed); 20677893d1d5SAdam Litke spin_lock(&hugetlb_lock); 20687893d1d5SAdam Litke if (!ret) 20697893d1d5SAdam Litke goto out; 20707893d1d5SAdam Litke 2071536240f2SMel Gorman /* Bail for signals. Probably ctrl-c from user */ 2072536240f2SMel Gorman if (signal_pending(current)) 2073536240f2SMel Gorman goto out; 20747893d1d5SAdam Litke } 20757893d1d5SAdam Litke 20767893d1d5SAdam Litke /* 20777893d1d5SAdam Litke * Decrease the pool size 20787893d1d5SAdam Litke * First return free pages to the buddy allocator (being careful 20797893d1d5SAdam Litke * to keep enough around to satisfy reservations). Then place 20807893d1d5SAdam Litke * pages into surplus state as needed so the pool will shrink 20817893d1d5SAdam Litke * to the desired size as pages become free. 2082d1c3fb1fSNishanth Aravamudan * 2083d1c3fb1fSNishanth Aravamudan * By placing pages into the surplus state independent of the 2084d1c3fb1fSNishanth Aravamudan * overcommit value, we are allowing the surplus pool size to 2085d1c3fb1fSNishanth Aravamudan * exceed overcommit. There are few sane options here. Since 2086d1c3fb1fSNishanth Aravamudan * alloc_buddy_huge_page() is checking the global counter, 2087d1c3fb1fSNishanth Aravamudan * though, we'll note that we're not allowed to exceed surplus 2088d1c3fb1fSNishanth Aravamudan * and won't grow the pool anywhere else. Not until one of the 2089d1c3fb1fSNishanth Aravamudan * sysctls are changed, or the surplus pages go out of use. 20907893d1d5SAdam Litke */ 2091a5516438SAndi Kleen min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages; 20926b0c880dSAdam Litke min_count = max(count, min_count); 20936ae11b27SLee Schermerhorn try_to_free_low(h, min_count, nodes_allowed); 2094a5516438SAndi Kleen while (min_count < persistent_huge_pages(h)) { 20956ae11b27SLee Schermerhorn if (!free_pool_huge_page(h, nodes_allowed, 0)) 20961da177e4SLinus Torvalds break; 209755f67141SMizuma, Masayoshi cond_resched_lock(&hugetlb_lock); 20981da177e4SLinus Torvalds } 2099a5516438SAndi Kleen while (count < persistent_huge_pages(h)) { 21006ae11b27SLee Schermerhorn if (!adjust_pool_surplus(h, nodes_allowed, 1)) 21017893d1d5SAdam Litke break; 21027893d1d5SAdam Litke } 21037893d1d5SAdam Litke out: 2104a5516438SAndi Kleen ret = persistent_huge_pages(h); 21051da177e4SLinus Torvalds spin_unlock(&hugetlb_lock); 21067893d1d5SAdam Litke return ret; 21071da177e4SLinus Torvalds } 21081da177e4SLinus Torvalds 2109a3437870SNishanth Aravamudan #define HSTATE_ATTR_RO(_name) \ 2110a3437870SNishanth Aravamudan static struct kobj_attribute _name##_attr = __ATTR_RO(_name) 2111a3437870SNishanth Aravamudan 2112a3437870SNishanth Aravamudan #define HSTATE_ATTR(_name) \ 2113a3437870SNishanth Aravamudan static struct kobj_attribute _name##_attr = \ 2114a3437870SNishanth Aravamudan __ATTR(_name, 0644, _name##_show, _name##_store) 2115a3437870SNishanth Aravamudan 2116a3437870SNishanth Aravamudan static struct kobject *hugepages_kobj; 2117a3437870SNishanth Aravamudan static struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; 2118a3437870SNishanth Aravamudan 21199a305230SLee Schermerhorn static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp); 21209a305230SLee Schermerhorn 21219a305230SLee Schermerhorn static struct hstate *kobj_to_hstate(struct kobject *kobj, int *nidp) 2122a3437870SNishanth Aravamudan { 2123a3437870SNishanth Aravamudan int i; 21249a305230SLee Schermerhorn 2125a3437870SNishanth Aravamudan for (i = 0; i < HUGE_MAX_HSTATE; i++) 21269a305230SLee Schermerhorn if (hstate_kobjs[i] == kobj) { 21279a305230SLee Schermerhorn if (nidp) 21289a305230SLee Schermerhorn *nidp = NUMA_NO_NODE; 2129a3437870SNishanth Aravamudan return &hstates[i]; 21309a305230SLee Schermerhorn } 21319a305230SLee Schermerhorn 21329a305230SLee Schermerhorn return kobj_to_node_hstate(kobj, nidp); 2133a3437870SNishanth Aravamudan } 2134a3437870SNishanth Aravamudan 213506808b08SLee Schermerhorn static ssize_t nr_hugepages_show_common(struct kobject *kobj, 2136a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2137a3437870SNishanth Aravamudan { 21389a305230SLee Schermerhorn struct hstate *h; 21399a305230SLee Schermerhorn unsigned long nr_huge_pages; 21409a305230SLee Schermerhorn int nid; 21419a305230SLee Schermerhorn 21429a305230SLee Schermerhorn h = kobj_to_hstate(kobj, &nid); 21439a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) 21449a305230SLee Schermerhorn nr_huge_pages = h->nr_huge_pages; 21459a305230SLee Schermerhorn else 21469a305230SLee Schermerhorn nr_huge_pages = h->nr_huge_pages_node[nid]; 21479a305230SLee Schermerhorn 21489a305230SLee Schermerhorn return sprintf(buf, "%lu\n", nr_huge_pages); 2149a3437870SNishanth Aravamudan } 2150adbe8726SEric B Munson 2151238d3c13SDavid Rientjes static ssize_t __nr_hugepages_store_common(bool obey_mempolicy, 2152238d3c13SDavid Rientjes struct hstate *h, int nid, 2153238d3c13SDavid Rientjes unsigned long count, size_t len) 2154a3437870SNishanth Aravamudan { 2155a3437870SNishanth Aravamudan int err; 2156bad44b5bSDavid Rientjes NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY); 2157a3437870SNishanth Aravamudan 2158944d9fecSLuiz Capitulino if (hstate_is_gigantic(h) && !gigantic_page_supported()) { 2159adbe8726SEric B Munson err = -EINVAL; 2160adbe8726SEric B Munson goto out; 2161adbe8726SEric B Munson } 2162adbe8726SEric B Munson 21639a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) { 21649a305230SLee Schermerhorn /* 21659a305230SLee Schermerhorn * global hstate attribute 21669a305230SLee Schermerhorn */ 21679a305230SLee Schermerhorn if (!(obey_mempolicy && 21689a305230SLee Schermerhorn init_nodemask_of_mempolicy(nodes_allowed))) { 216906808b08SLee Schermerhorn NODEMASK_FREE(nodes_allowed); 21708cebfcd0SLai Jiangshan nodes_allowed = &node_states[N_MEMORY]; 217106808b08SLee Schermerhorn } 21729a305230SLee Schermerhorn } else if (nodes_allowed) { 21739a305230SLee Schermerhorn /* 21749a305230SLee Schermerhorn * per node hstate attribute: adjust count to global, 21759a305230SLee Schermerhorn * but restrict alloc/free to the specified node. 21769a305230SLee Schermerhorn */ 21779a305230SLee Schermerhorn count += h->nr_huge_pages - h->nr_huge_pages_node[nid]; 21789a305230SLee Schermerhorn init_nodemask_of_node(nodes_allowed, nid); 21799a305230SLee Schermerhorn } else 21808cebfcd0SLai Jiangshan nodes_allowed = &node_states[N_MEMORY]; 21819a305230SLee Schermerhorn 218206808b08SLee Schermerhorn h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed); 2183a3437870SNishanth Aravamudan 21848cebfcd0SLai Jiangshan if (nodes_allowed != &node_states[N_MEMORY]) 218506808b08SLee Schermerhorn NODEMASK_FREE(nodes_allowed); 218606808b08SLee Schermerhorn 218706808b08SLee Schermerhorn return len; 2188adbe8726SEric B Munson out: 2189adbe8726SEric B Munson NODEMASK_FREE(nodes_allowed); 2190adbe8726SEric B Munson return err; 219106808b08SLee Schermerhorn } 219206808b08SLee Schermerhorn 2193238d3c13SDavid Rientjes static ssize_t nr_hugepages_store_common(bool obey_mempolicy, 2194238d3c13SDavid Rientjes struct kobject *kobj, const char *buf, 2195238d3c13SDavid Rientjes size_t len) 2196238d3c13SDavid Rientjes { 2197238d3c13SDavid Rientjes struct hstate *h; 2198238d3c13SDavid Rientjes unsigned long count; 2199238d3c13SDavid Rientjes int nid; 2200238d3c13SDavid Rientjes int err; 2201238d3c13SDavid Rientjes 2202238d3c13SDavid Rientjes err = kstrtoul(buf, 10, &count); 2203238d3c13SDavid Rientjes if (err) 2204238d3c13SDavid Rientjes return err; 2205238d3c13SDavid Rientjes 2206238d3c13SDavid Rientjes h = kobj_to_hstate(kobj, &nid); 2207238d3c13SDavid Rientjes return __nr_hugepages_store_common(obey_mempolicy, h, nid, count, len); 2208238d3c13SDavid Rientjes } 2209238d3c13SDavid Rientjes 221006808b08SLee Schermerhorn static ssize_t nr_hugepages_show(struct kobject *kobj, 221106808b08SLee Schermerhorn struct kobj_attribute *attr, char *buf) 221206808b08SLee Schermerhorn { 221306808b08SLee Schermerhorn return nr_hugepages_show_common(kobj, attr, buf); 221406808b08SLee Schermerhorn } 221506808b08SLee Schermerhorn 221606808b08SLee Schermerhorn static ssize_t nr_hugepages_store(struct kobject *kobj, 221706808b08SLee Schermerhorn struct kobj_attribute *attr, const char *buf, size_t len) 221806808b08SLee Schermerhorn { 2219238d3c13SDavid Rientjes return nr_hugepages_store_common(false, kobj, buf, len); 2220a3437870SNishanth Aravamudan } 2221a3437870SNishanth Aravamudan HSTATE_ATTR(nr_hugepages); 2222a3437870SNishanth Aravamudan 222306808b08SLee Schermerhorn #ifdef CONFIG_NUMA 222406808b08SLee Schermerhorn 222506808b08SLee Schermerhorn /* 222606808b08SLee Schermerhorn * hstate attribute for optionally mempolicy-based constraint on persistent 222706808b08SLee Schermerhorn * huge page alloc/free. 222806808b08SLee Schermerhorn */ 222906808b08SLee Schermerhorn static ssize_t nr_hugepages_mempolicy_show(struct kobject *kobj, 223006808b08SLee Schermerhorn struct kobj_attribute *attr, char *buf) 223106808b08SLee Schermerhorn { 223206808b08SLee Schermerhorn return nr_hugepages_show_common(kobj, attr, buf); 223306808b08SLee Schermerhorn } 223406808b08SLee Schermerhorn 223506808b08SLee Schermerhorn static ssize_t nr_hugepages_mempolicy_store(struct kobject *kobj, 223606808b08SLee Schermerhorn struct kobj_attribute *attr, const char *buf, size_t len) 223706808b08SLee Schermerhorn { 2238238d3c13SDavid Rientjes return nr_hugepages_store_common(true, kobj, buf, len); 223906808b08SLee Schermerhorn } 224006808b08SLee Schermerhorn HSTATE_ATTR(nr_hugepages_mempolicy); 224106808b08SLee Schermerhorn #endif 224206808b08SLee Schermerhorn 224306808b08SLee Schermerhorn 2244a3437870SNishanth Aravamudan static ssize_t nr_overcommit_hugepages_show(struct kobject *kobj, 2245a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2246a3437870SNishanth Aravamudan { 22479a305230SLee Schermerhorn struct hstate *h = kobj_to_hstate(kobj, NULL); 2248a3437870SNishanth Aravamudan return sprintf(buf, "%lu\n", h->nr_overcommit_huge_pages); 2249a3437870SNishanth Aravamudan } 2250adbe8726SEric B Munson 2251a3437870SNishanth Aravamudan static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, 2252a3437870SNishanth Aravamudan struct kobj_attribute *attr, const char *buf, size_t count) 2253a3437870SNishanth Aravamudan { 2254a3437870SNishanth Aravamudan int err; 2255a3437870SNishanth Aravamudan unsigned long input; 22569a305230SLee Schermerhorn struct hstate *h = kobj_to_hstate(kobj, NULL); 2257a3437870SNishanth Aravamudan 2258bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 2259adbe8726SEric B Munson return -EINVAL; 2260adbe8726SEric B Munson 22613dbb95f7SJingoo Han err = kstrtoul(buf, 10, &input); 2262a3437870SNishanth Aravamudan if (err) 226373ae31e5SEric B Munson return err; 2264a3437870SNishanth Aravamudan 2265a3437870SNishanth Aravamudan spin_lock(&hugetlb_lock); 2266a3437870SNishanth Aravamudan h->nr_overcommit_huge_pages = input; 2267a3437870SNishanth Aravamudan spin_unlock(&hugetlb_lock); 2268a3437870SNishanth Aravamudan 2269a3437870SNishanth Aravamudan return count; 2270a3437870SNishanth Aravamudan } 2271a3437870SNishanth Aravamudan HSTATE_ATTR(nr_overcommit_hugepages); 2272a3437870SNishanth Aravamudan 2273a3437870SNishanth Aravamudan static ssize_t free_hugepages_show(struct kobject *kobj, 2274a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2275a3437870SNishanth Aravamudan { 22769a305230SLee Schermerhorn struct hstate *h; 22779a305230SLee Schermerhorn unsigned long free_huge_pages; 22789a305230SLee Schermerhorn int nid; 22799a305230SLee Schermerhorn 22809a305230SLee Schermerhorn h = kobj_to_hstate(kobj, &nid); 22819a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) 22829a305230SLee Schermerhorn free_huge_pages = h->free_huge_pages; 22839a305230SLee Schermerhorn else 22849a305230SLee Schermerhorn free_huge_pages = h->free_huge_pages_node[nid]; 22859a305230SLee Schermerhorn 22869a305230SLee Schermerhorn return sprintf(buf, "%lu\n", free_huge_pages); 2287a3437870SNishanth Aravamudan } 2288a3437870SNishanth Aravamudan HSTATE_ATTR_RO(free_hugepages); 2289a3437870SNishanth Aravamudan 2290a3437870SNishanth Aravamudan static ssize_t resv_hugepages_show(struct kobject *kobj, 2291a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2292a3437870SNishanth Aravamudan { 22939a305230SLee Schermerhorn struct hstate *h = kobj_to_hstate(kobj, NULL); 2294a3437870SNishanth Aravamudan return sprintf(buf, "%lu\n", h->resv_huge_pages); 2295a3437870SNishanth Aravamudan } 2296a3437870SNishanth Aravamudan HSTATE_ATTR_RO(resv_hugepages); 2297a3437870SNishanth Aravamudan 2298a3437870SNishanth Aravamudan static ssize_t surplus_hugepages_show(struct kobject *kobj, 2299a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2300a3437870SNishanth Aravamudan { 23019a305230SLee Schermerhorn struct hstate *h; 23029a305230SLee Schermerhorn unsigned long surplus_huge_pages; 23039a305230SLee Schermerhorn int nid; 23049a305230SLee Schermerhorn 23059a305230SLee Schermerhorn h = kobj_to_hstate(kobj, &nid); 23069a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) 23079a305230SLee Schermerhorn surplus_huge_pages = h->surplus_huge_pages; 23089a305230SLee Schermerhorn else 23099a305230SLee Schermerhorn surplus_huge_pages = h->surplus_huge_pages_node[nid]; 23109a305230SLee Schermerhorn 23119a305230SLee Schermerhorn return sprintf(buf, "%lu\n", surplus_huge_pages); 2312a3437870SNishanth Aravamudan } 2313a3437870SNishanth Aravamudan HSTATE_ATTR_RO(surplus_hugepages); 2314a3437870SNishanth Aravamudan 2315a3437870SNishanth Aravamudan static struct attribute *hstate_attrs[] = { 2316a3437870SNishanth Aravamudan &nr_hugepages_attr.attr, 2317a3437870SNishanth Aravamudan &nr_overcommit_hugepages_attr.attr, 2318a3437870SNishanth Aravamudan &free_hugepages_attr.attr, 2319a3437870SNishanth Aravamudan &resv_hugepages_attr.attr, 2320a3437870SNishanth Aravamudan &surplus_hugepages_attr.attr, 232106808b08SLee Schermerhorn #ifdef CONFIG_NUMA 232206808b08SLee Schermerhorn &nr_hugepages_mempolicy_attr.attr, 232306808b08SLee Schermerhorn #endif 2324a3437870SNishanth Aravamudan NULL, 2325a3437870SNishanth Aravamudan }; 2326a3437870SNishanth Aravamudan 2327a3437870SNishanth Aravamudan static struct attribute_group hstate_attr_group = { 2328a3437870SNishanth Aravamudan .attrs = hstate_attrs, 2329a3437870SNishanth Aravamudan }; 2330a3437870SNishanth Aravamudan 2331094e9539SJeff Mahoney static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent, 23329a305230SLee Schermerhorn struct kobject **hstate_kobjs, 23339a305230SLee Schermerhorn struct attribute_group *hstate_attr_group) 2334a3437870SNishanth Aravamudan { 2335a3437870SNishanth Aravamudan int retval; 2336972dc4deSAneesh Kumar K.V int hi = hstate_index(h); 2337a3437870SNishanth Aravamudan 23389a305230SLee Schermerhorn hstate_kobjs[hi] = kobject_create_and_add(h->name, parent); 23399a305230SLee Schermerhorn if (!hstate_kobjs[hi]) 2340a3437870SNishanth Aravamudan return -ENOMEM; 2341a3437870SNishanth Aravamudan 23429a305230SLee Schermerhorn retval = sysfs_create_group(hstate_kobjs[hi], hstate_attr_group); 2343a3437870SNishanth Aravamudan if (retval) 23449a305230SLee Schermerhorn kobject_put(hstate_kobjs[hi]); 2345a3437870SNishanth Aravamudan 2346a3437870SNishanth Aravamudan return retval; 2347a3437870SNishanth Aravamudan } 2348a3437870SNishanth Aravamudan 2349a3437870SNishanth Aravamudan static void __init hugetlb_sysfs_init(void) 2350a3437870SNishanth Aravamudan { 2351a3437870SNishanth Aravamudan struct hstate *h; 2352a3437870SNishanth Aravamudan int err; 2353a3437870SNishanth Aravamudan 2354a3437870SNishanth Aravamudan hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj); 2355a3437870SNishanth Aravamudan if (!hugepages_kobj) 2356a3437870SNishanth Aravamudan return; 2357a3437870SNishanth Aravamudan 2358a3437870SNishanth Aravamudan for_each_hstate(h) { 23599a305230SLee Schermerhorn err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, 23609a305230SLee Schermerhorn hstate_kobjs, &hstate_attr_group); 2361a3437870SNishanth Aravamudan if (err) 2362ffb22af5SAndrew Morton pr_err("Hugetlb: Unable to add hstate %s", h->name); 2363a3437870SNishanth Aravamudan } 2364a3437870SNishanth Aravamudan } 2365a3437870SNishanth Aravamudan 23669a305230SLee Schermerhorn #ifdef CONFIG_NUMA 23679a305230SLee Schermerhorn 23689a305230SLee Schermerhorn /* 23699a305230SLee Schermerhorn * node_hstate/s - associate per node hstate attributes, via their kobjects, 237010fbcf4cSKay Sievers * with node devices in node_devices[] using a parallel array. The array 237110fbcf4cSKay Sievers * index of a node device or _hstate == node id. 237210fbcf4cSKay Sievers * This is here to avoid any static dependency of the node device driver, in 23739a305230SLee Schermerhorn * the base kernel, on the hugetlb module. 23749a305230SLee Schermerhorn */ 23759a305230SLee Schermerhorn struct node_hstate { 23769a305230SLee Schermerhorn struct kobject *hugepages_kobj; 23779a305230SLee Schermerhorn struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; 23789a305230SLee Schermerhorn }; 23799a305230SLee Schermerhorn struct node_hstate node_hstates[MAX_NUMNODES]; 23809a305230SLee Schermerhorn 23819a305230SLee Schermerhorn /* 238210fbcf4cSKay Sievers * A subset of global hstate attributes for node devices 23839a305230SLee Schermerhorn */ 23849a305230SLee Schermerhorn static struct attribute *per_node_hstate_attrs[] = { 23859a305230SLee Schermerhorn &nr_hugepages_attr.attr, 23869a305230SLee Schermerhorn &free_hugepages_attr.attr, 23879a305230SLee Schermerhorn &surplus_hugepages_attr.attr, 23889a305230SLee Schermerhorn NULL, 23899a305230SLee Schermerhorn }; 23909a305230SLee Schermerhorn 23919a305230SLee Schermerhorn static struct attribute_group per_node_hstate_attr_group = { 23929a305230SLee Schermerhorn .attrs = per_node_hstate_attrs, 23939a305230SLee Schermerhorn }; 23949a305230SLee Schermerhorn 23959a305230SLee Schermerhorn /* 239610fbcf4cSKay Sievers * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj. 23979a305230SLee Schermerhorn * Returns node id via non-NULL nidp. 23989a305230SLee Schermerhorn */ 23999a305230SLee Schermerhorn static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) 24009a305230SLee Schermerhorn { 24019a305230SLee Schermerhorn int nid; 24029a305230SLee Schermerhorn 24039a305230SLee Schermerhorn for (nid = 0; nid < nr_node_ids; nid++) { 24049a305230SLee Schermerhorn struct node_hstate *nhs = &node_hstates[nid]; 24059a305230SLee Schermerhorn int i; 24069a305230SLee Schermerhorn for (i = 0; i < HUGE_MAX_HSTATE; i++) 24079a305230SLee Schermerhorn if (nhs->hstate_kobjs[i] == kobj) { 24089a305230SLee Schermerhorn if (nidp) 24099a305230SLee Schermerhorn *nidp = nid; 24109a305230SLee Schermerhorn return &hstates[i]; 24119a305230SLee Schermerhorn } 24129a305230SLee Schermerhorn } 24139a305230SLee Schermerhorn 24149a305230SLee Schermerhorn BUG(); 24159a305230SLee Schermerhorn return NULL; 24169a305230SLee Schermerhorn } 24179a305230SLee Schermerhorn 24189a305230SLee Schermerhorn /* 241910fbcf4cSKay Sievers * Unregister hstate attributes from a single node device. 24209a305230SLee Schermerhorn * No-op if no hstate attributes attached. 24219a305230SLee Schermerhorn */ 24223cd8b44fSClaudiu Ghioc static void hugetlb_unregister_node(struct node *node) 24239a305230SLee Schermerhorn { 24249a305230SLee Schermerhorn struct hstate *h; 242510fbcf4cSKay Sievers struct node_hstate *nhs = &node_hstates[node->dev.id]; 24269a305230SLee Schermerhorn 24279a305230SLee Schermerhorn if (!nhs->hugepages_kobj) 24289b5e5d0fSLee Schermerhorn return; /* no hstate attributes */ 24299a305230SLee Schermerhorn 2430972dc4deSAneesh Kumar K.V for_each_hstate(h) { 2431972dc4deSAneesh Kumar K.V int idx = hstate_index(h); 2432972dc4deSAneesh Kumar K.V if (nhs->hstate_kobjs[idx]) { 2433972dc4deSAneesh Kumar K.V kobject_put(nhs->hstate_kobjs[idx]); 2434972dc4deSAneesh Kumar K.V nhs->hstate_kobjs[idx] = NULL; 2435972dc4deSAneesh Kumar K.V } 24369a305230SLee Schermerhorn } 24379a305230SLee Schermerhorn 24389a305230SLee Schermerhorn kobject_put(nhs->hugepages_kobj); 24399a305230SLee Schermerhorn nhs->hugepages_kobj = NULL; 24409a305230SLee Schermerhorn } 24419a305230SLee Schermerhorn 24429a305230SLee Schermerhorn /* 244310fbcf4cSKay Sievers * hugetlb module exit: unregister hstate attributes from node devices 24449a305230SLee Schermerhorn * that have them. 24459a305230SLee Schermerhorn */ 24469a305230SLee Schermerhorn static void hugetlb_unregister_all_nodes(void) 24479a305230SLee Schermerhorn { 24489a305230SLee Schermerhorn int nid; 24499a305230SLee Schermerhorn 24509a305230SLee Schermerhorn /* 245110fbcf4cSKay Sievers * disable node device registrations. 24529a305230SLee Schermerhorn */ 24539a305230SLee Schermerhorn register_hugetlbfs_with_node(NULL, NULL); 24549a305230SLee Schermerhorn 24559a305230SLee Schermerhorn /* 24569a305230SLee Schermerhorn * remove hstate attributes from any nodes that have them. 24579a305230SLee Schermerhorn */ 24589a305230SLee Schermerhorn for (nid = 0; nid < nr_node_ids; nid++) 24598732794bSWen Congyang hugetlb_unregister_node(node_devices[nid]); 24609a305230SLee Schermerhorn } 24619a305230SLee Schermerhorn 24629a305230SLee Schermerhorn /* 246310fbcf4cSKay Sievers * Register hstate attributes for a single node device. 24649a305230SLee Schermerhorn * No-op if attributes already registered. 24659a305230SLee Schermerhorn */ 24663cd8b44fSClaudiu Ghioc static void hugetlb_register_node(struct node *node) 24679a305230SLee Schermerhorn { 24689a305230SLee Schermerhorn struct hstate *h; 246910fbcf4cSKay Sievers struct node_hstate *nhs = &node_hstates[node->dev.id]; 24709a305230SLee Schermerhorn int err; 24719a305230SLee Schermerhorn 24729a305230SLee Schermerhorn if (nhs->hugepages_kobj) 24739a305230SLee Schermerhorn return; /* already allocated */ 24749a305230SLee Schermerhorn 24759a305230SLee Schermerhorn nhs->hugepages_kobj = kobject_create_and_add("hugepages", 247610fbcf4cSKay Sievers &node->dev.kobj); 24779a305230SLee Schermerhorn if (!nhs->hugepages_kobj) 24789a305230SLee Schermerhorn return; 24799a305230SLee Schermerhorn 24809a305230SLee Schermerhorn for_each_hstate(h) { 24819a305230SLee Schermerhorn err = hugetlb_sysfs_add_hstate(h, nhs->hugepages_kobj, 24829a305230SLee Schermerhorn nhs->hstate_kobjs, 24839a305230SLee Schermerhorn &per_node_hstate_attr_group); 24849a305230SLee Schermerhorn if (err) { 2485ffb22af5SAndrew Morton pr_err("Hugetlb: Unable to add hstate %s for node %d\n", 248610fbcf4cSKay Sievers h->name, node->dev.id); 24879a305230SLee Schermerhorn hugetlb_unregister_node(node); 24889a305230SLee Schermerhorn break; 24899a305230SLee Schermerhorn } 24909a305230SLee Schermerhorn } 24919a305230SLee Schermerhorn } 24929a305230SLee Schermerhorn 24939a305230SLee Schermerhorn /* 24949b5e5d0fSLee Schermerhorn * hugetlb init time: register hstate attributes for all registered node 249510fbcf4cSKay Sievers * devices of nodes that have memory. All on-line nodes should have 249610fbcf4cSKay Sievers * registered their associated device by this time. 24979a305230SLee Schermerhorn */ 24987d9ca000SLuiz Capitulino static void __init hugetlb_register_all_nodes(void) 24999a305230SLee Schermerhorn { 25009a305230SLee Schermerhorn int nid; 25019a305230SLee Schermerhorn 25028cebfcd0SLai Jiangshan for_each_node_state(nid, N_MEMORY) { 25038732794bSWen Congyang struct node *node = node_devices[nid]; 250410fbcf4cSKay Sievers if (node->dev.id == nid) 25059a305230SLee Schermerhorn hugetlb_register_node(node); 25069a305230SLee Schermerhorn } 25079a305230SLee Schermerhorn 25089a305230SLee Schermerhorn /* 250910fbcf4cSKay Sievers * Let the node device driver know we're here so it can 25109a305230SLee Schermerhorn * [un]register hstate attributes on node hotplug. 25119a305230SLee Schermerhorn */ 25129a305230SLee Schermerhorn register_hugetlbfs_with_node(hugetlb_register_node, 25139a305230SLee Schermerhorn hugetlb_unregister_node); 25149a305230SLee Schermerhorn } 25159a305230SLee Schermerhorn #else /* !CONFIG_NUMA */ 25169a305230SLee Schermerhorn 25179a305230SLee Schermerhorn static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) 25189a305230SLee Schermerhorn { 25199a305230SLee Schermerhorn BUG(); 25209a305230SLee Schermerhorn if (nidp) 25219a305230SLee Schermerhorn *nidp = -1; 25229a305230SLee Schermerhorn return NULL; 25239a305230SLee Schermerhorn } 25249a305230SLee Schermerhorn 25259a305230SLee Schermerhorn static void hugetlb_unregister_all_nodes(void) { } 25269a305230SLee Schermerhorn 25279a305230SLee Schermerhorn static void hugetlb_register_all_nodes(void) { } 25289a305230SLee Schermerhorn 25299a305230SLee Schermerhorn #endif 25309a305230SLee Schermerhorn 2531a3437870SNishanth Aravamudan static void __exit hugetlb_exit(void) 2532a3437870SNishanth Aravamudan { 2533a3437870SNishanth Aravamudan struct hstate *h; 2534a3437870SNishanth Aravamudan 25359a305230SLee Schermerhorn hugetlb_unregister_all_nodes(); 25369a305230SLee Schermerhorn 2537a3437870SNishanth Aravamudan for_each_hstate(h) { 2538972dc4deSAneesh Kumar K.V kobject_put(hstate_kobjs[hstate_index(h)]); 2539a3437870SNishanth Aravamudan } 2540a3437870SNishanth Aravamudan 2541a3437870SNishanth Aravamudan kobject_put(hugepages_kobj); 2542c672c7f2SMike Kravetz kfree(hugetlb_fault_mutex_table); 2543a3437870SNishanth Aravamudan } 2544a3437870SNishanth Aravamudan module_exit(hugetlb_exit); 2545a3437870SNishanth Aravamudan 2546a3437870SNishanth Aravamudan static int __init hugetlb_init(void) 2547a3437870SNishanth Aravamudan { 25488382d914SDavidlohr Bueso int i; 25498382d914SDavidlohr Bueso 2550457c1b27SNishanth Aravamudan if (!hugepages_supported()) 25510ef89d25SBenjamin Herrenschmidt return 0; 2552a3437870SNishanth Aravamudan 2553e11bfbfcSNick Piggin if (!size_to_hstate(default_hstate_size)) { 2554e11bfbfcSNick Piggin default_hstate_size = HPAGE_SIZE; 2555e11bfbfcSNick Piggin if (!size_to_hstate(default_hstate_size)) 2556a3437870SNishanth Aravamudan hugetlb_add_hstate(HUGETLB_PAGE_ORDER); 2557a3437870SNishanth Aravamudan } 2558972dc4deSAneesh Kumar K.V default_hstate_idx = hstate_index(size_to_hstate(default_hstate_size)); 2559e11bfbfcSNick Piggin if (default_hstate_max_huge_pages) 2560e11bfbfcSNick Piggin default_hstate.max_huge_pages = default_hstate_max_huge_pages; 2561a3437870SNishanth Aravamudan 2562a3437870SNishanth Aravamudan hugetlb_init_hstates(); 2563aa888a74SAndi Kleen gather_bootmem_prealloc(); 2564a3437870SNishanth Aravamudan report_hugepages(); 2565a3437870SNishanth Aravamudan 2566a3437870SNishanth Aravamudan hugetlb_sysfs_init(); 25679a305230SLee Schermerhorn hugetlb_register_all_nodes(); 25687179e7bfSJianguo Wu hugetlb_cgroup_file_init(); 25699a305230SLee Schermerhorn 25708382d914SDavidlohr Bueso #ifdef CONFIG_SMP 25718382d914SDavidlohr Bueso num_fault_mutexes = roundup_pow_of_two(8 * num_possible_cpus()); 25728382d914SDavidlohr Bueso #else 25738382d914SDavidlohr Bueso num_fault_mutexes = 1; 25748382d914SDavidlohr Bueso #endif 2575c672c7f2SMike Kravetz hugetlb_fault_mutex_table = 25768382d914SDavidlohr Bueso kmalloc(sizeof(struct mutex) * num_fault_mutexes, GFP_KERNEL); 2577c672c7f2SMike Kravetz BUG_ON(!hugetlb_fault_mutex_table); 25788382d914SDavidlohr Bueso 25798382d914SDavidlohr Bueso for (i = 0; i < num_fault_mutexes; i++) 2580c672c7f2SMike Kravetz mutex_init(&hugetlb_fault_mutex_table[i]); 2581a3437870SNishanth Aravamudan return 0; 2582a3437870SNishanth Aravamudan } 2583a3437870SNishanth Aravamudan module_init(hugetlb_init); 2584a3437870SNishanth Aravamudan 2585a3437870SNishanth Aravamudan /* Should be called on processing a hugepagesz=... option */ 2586a3437870SNishanth Aravamudan void __init hugetlb_add_hstate(unsigned order) 2587a3437870SNishanth Aravamudan { 2588a3437870SNishanth Aravamudan struct hstate *h; 25898faa8b07SAndi Kleen unsigned long i; 25908faa8b07SAndi Kleen 2591a3437870SNishanth Aravamudan if (size_to_hstate(PAGE_SIZE << order)) { 2592ffb22af5SAndrew Morton pr_warning("hugepagesz= specified twice, ignoring\n"); 2593a3437870SNishanth Aravamudan return; 2594a3437870SNishanth Aravamudan } 259547d38344SAneesh Kumar K.V BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE); 2596a3437870SNishanth Aravamudan BUG_ON(order == 0); 259747d38344SAneesh Kumar K.V h = &hstates[hugetlb_max_hstate++]; 2598a3437870SNishanth Aravamudan h->order = order; 2599a3437870SNishanth Aravamudan h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1); 26008faa8b07SAndi Kleen h->nr_huge_pages = 0; 26018faa8b07SAndi Kleen h->free_huge_pages = 0; 26028faa8b07SAndi Kleen for (i = 0; i < MAX_NUMNODES; ++i) 26038faa8b07SAndi Kleen INIT_LIST_HEAD(&h->hugepage_freelists[i]); 26040edaecfaSAneesh Kumar K.V INIT_LIST_HEAD(&h->hugepage_activelist); 26058cebfcd0SLai Jiangshan h->next_nid_to_alloc = first_node(node_states[N_MEMORY]); 26068cebfcd0SLai Jiangshan h->next_nid_to_free = first_node(node_states[N_MEMORY]); 2607a3437870SNishanth Aravamudan snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB", 2608a3437870SNishanth Aravamudan huge_page_size(h)/1024); 26098faa8b07SAndi Kleen 2610a3437870SNishanth Aravamudan parsed_hstate = h; 2611a3437870SNishanth Aravamudan } 2612a3437870SNishanth Aravamudan 2613e11bfbfcSNick Piggin static int __init hugetlb_nrpages_setup(char *s) 2614a3437870SNishanth Aravamudan { 2615a3437870SNishanth Aravamudan unsigned long *mhp; 26168faa8b07SAndi Kleen static unsigned long *last_mhp; 2617a3437870SNishanth Aravamudan 2618a3437870SNishanth Aravamudan /* 261947d38344SAneesh Kumar K.V * !hugetlb_max_hstate means we haven't parsed a hugepagesz= parameter yet, 2620a3437870SNishanth Aravamudan * so this hugepages= parameter goes to the "default hstate". 2621a3437870SNishanth Aravamudan */ 262247d38344SAneesh Kumar K.V if (!hugetlb_max_hstate) 2623a3437870SNishanth Aravamudan mhp = &default_hstate_max_huge_pages; 2624a3437870SNishanth Aravamudan else 2625a3437870SNishanth Aravamudan mhp = &parsed_hstate->max_huge_pages; 2626a3437870SNishanth Aravamudan 26278faa8b07SAndi Kleen if (mhp == last_mhp) { 2628ffb22af5SAndrew Morton pr_warning("hugepages= specified twice without " 26298faa8b07SAndi Kleen "interleaving hugepagesz=, ignoring\n"); 26308faa8b07SAndi Kleen return 1; 26318faa8b07SAndi Kleen } 26328faa8b07SAndi Kleen 2633a3437870SNishanth Aravamudan if (sscanf(s, "%lu", mhp) <= 0) 2634a3437870SNishanth Aravamudan *mhp = 0; 2635a3437870SNishanth Aravamudan 26368faa8b07SAndi Kleen /* 26378faa8b07SAndi Kleen * Global state is always initialized later in hugetlb_init. 26388faa8b07SAndi Kleen * But we need to allocate >= MAX_ORDER hstates here early to still 26398faa8b07SAndi Kleen * use the bootmem allocator. 26408faa8b07SAndi Kleen */ 264147d38344SAneesh Kumar K.V if (hugetlb_max_hstate && parsed_hstate->order >= MAX_ORDER) 26428faa8b07SAndi Kleen hugetlb_hstate_alloc_pages(parsed_hstate); 26438faa8b07SAndi Kleen 26448faa8b07SAndi Kleen last_mhp = mhp; 26458faa8b07SAndi Kleen 2646a3437870SNishanth Aravamudan return 1; 2647a3437870SNishanth Aravamudan } 2648e11bfbfcSNick Piggin __setup("hugepages=", hugetlb_nrpages_setup); 2649e11bfbfcSNick Piggin 2650e11bfbfcSNick Piggin static int __init hugetlb_default_setup(char *s) 2651e11bfbfcSNick Piggin { 2652e11bfbfcSNick Piggin default_hstate_size = memparse(s, &s); 2653e11bfbfcSNick Piggin return 1; 2654e11bfbfcSNick Piggin } 2655e11bfbfcSNick Piggin __setup("default_hugepagesz=", hugetlb_default_setup); 2656a3437870SNishanth Aravamudan 26578a213460SNishanth Aravamudan static unsigned int cpuset_mems_nr(unsigned int *array) 26588a213460SNishanth Aravamudan { 26598a213460SNishanth Aravamudan int node; 26608a213460SNishanth Aravamudan unsigned int nr = 0; 26618a213460SNishanth Aravamudan 26628a213460SNishanth Aravamudan for_each_node_mask(node, cpuset_current_mems_allowed) 26638a213460SNishanth Aravamudan nr += array[node]; 26648a213460SNishanth Aravamudan 26658a213460SNishanth Aravamudan return nr; 26668a213460SNishanth Aravamudan } 26678a213460SNishanth Aravamudan 26688a213460SNishanth Aravamudan #ifdef CONFIG_SYSCTL 266906808b08SLee Schermerhorn static int hugetlb_sysctl_handler_common(bool obey_mempolicy, 267006808b08SLee Schermerhorn struct ctl_table *table, int write, 267106808b08SLee Schermerhorn void __user *buffer, size_t *length, loff_t *ppos) 26721da177e4SLinus Torvalds { 2673e5ff2159SAndi Kleen struct hstate *h = &default_hstate; 2674238d3c13SDavid Rientjes unsigned long tmp = h->max_huge_pages; 267508d4a246SMichal Hocko int ret; 2676e5ff2159SAndi Kleen 2677457c1b27SNishanth Aravamudan if (!hugepages_supported()) 2678457c1b27SNishanth Aravamudan return -ENOTSUPP; 2679457c1b27SNishanth Aravamudan 2680e5ff2159SAndi Kleen table->data = &tmp; 2681e5ff2159SAndi Kleen table->maxlen = sizeof(unsigned long); 268208d4a246SMichal Hocko ret = proc_doulongvec_minmax(table, write, buffer, length, ppos); 268308d4a246SMichal Hocko if (ret) 268408d4a246SMichal Hocko goto out; 2685e5ff2159SAndi Kleen 2686238d3c13SDavid Rientjes if (write) 2687238d3c13SDavid Rientjes ret = __nr_hugepages_store_common(obey_mempolicy, h, 2688238d3c13SDavid Rientjes NUMA_NO_NODE, tmp, *length); 268908d4a246SMichal Hocko out: 269008d4a246SMichal Hocko return ret; 26911da177e4SLinus Torvalds } 2692396faf03SMel Gorman 269306808b08SLee Schermerhorn int hugetlb_sysctl_handler(struct ctl_table *table, int write, 269406808b08SLee Schermerhorn void __user *buffer, size_t *length, loff_t *ppos) 269506808b08SLee Schermerhorn { 269606808b08SLee Schermerhorn 269706808b08SLee Schermerhorn return hugetlb_sysctl_handler_common(false, table, write, 269806808b08SLee Schermerhorn buffer, length, ppos); 269906808b08SLee Schermerhorn } 270006808b08SLee Schermerhorn 270106808b08SLee Schermerhorn #ifdef CONFIG_NUMA 270206808b08SLee Schermerhorn int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, 270306808b08SLee Schermerhorn void __user *buffer, size_t *length, loff_t *ppos) 270406808b08SLee Schermerhorn { 270506808b08SLee Schermerhorn return hugetlb_sysctl_handler_common(true, table, write, 270606808b08SLee Schermerhorn buffer, length, ppos); 270706808b08SLee Schermerhorn } 270806808b08SLee Schermerhorn #endif /* CONFIG_NUMA */ 270906808b08SLee Schermerhorn 2710a3d0c6aaSNishanth Aravamudan int hugetlb_overcommit_handler(struct ctl_table *table, int write, 27118d65af78SAlexey Dobriyan void __user *buffer, 2712a3d0c6aaSNishanth Aravamudan size_t *length, loff_t *ppos) 2713a3d0c6aaSNishanth Aravamudan { 2714a5516438SAndi Kleen struct hstate *h = &default_hstate; 2715e5ff2159SAndi Kleen unsigned long tmp; 271608d4a246SMichal Hocko int ret; 2717e5ff2159SAndi Kleen 2718457c1b27SNishanth Aravamudan if (!hugepages_supported()) 2719457c1b27SNishanth Aravamudan return -ENOTSUPP; 2720457c1b27SNishanth Aravamudan 2721e5ff2159SAndi Kleen tmp = h->nr_overcommit_huge_pages; 2722e5ff2159SAndi Kleen 2723bae7f4aeSLuiz Capitulino if (write && hstate_is_gigantic(h)) 2724adbe8726SEric B Munson return -EINVAL; 2725adbe8726SEric B Munson 2726e5ff2159SAndi Kleen table->data = &tmp; 2727e5ff2159SAndi Kleen table->maxlen = sizeof(unsigned long); 272808d4a246SMichal Hocko ret = proc_doulongvec_minmax(table, write, buffer, length, ppos); 272908d4a246SMichal Hocko if (ret) 273008d4a246SMichal Hocko goto out; 2731e5ff2159SAndi Kleen 2732e5ff2159SAndi Kleen if (write) { 2733064d9efeSNishanth Aravamudan spin_lock(&hugetlb_lock); 2734e5ff2159SAndi Kleen h->nr_overcommit_huge_pages = tmp; 2735a3d0c6aaSNishanth Aravamudan spin_unlock(&hugetlb_lock); 2736e5ff2159SAndi Kleen } 273708d4a246SMichal Hocko out: 273808d4a246SMichal Hocko return ret; 2739a3d0c6aaSNishanth Aravamudan } 2740a3d0c6aaSNishanth Aravamudan 27411da177e4SLinus Torvalds #endif /* CONFIG_SYSCTL */ 27421da177e4SLinus Torvalds 2743e1759c21SAlexey Dobriyan void hugetlb_report_meminfo(struct seq_file *m) 27441da177e4SLinus Torvalds { 2745a5516438SAndi Kleen struct hstate *h = &default_hstate; 2746457c1b27SNishanth Aravamudan if (!hugepages_supported()) 2747457c1b27SNishanth Aravamudan return; 2748e1759c21SAlexey Dobriyan seq_printf(m, 27491da177e4SLinus Torvalds "HugePages_Total: %5lu\n" 27501da177e4SLinus Torvalds "HugePages_Free: %5lu\n" 2751b45b5bd6SDavid Gibson "HugePages_Rsvd: %5lu\n" 27527893d1d5SAdam Litke "HugePages_Surp: %5lu\n" 27534f98a2feSRik van Riel "Hugepagesize: %8lu kB\n", 2754a5516438SAndi Kleen h->nr_huge_pages, 2755a5516438SAndi Kleen h->free_huge_pages, 2756a5516438SAndi Kleen h->resv_huge_pages, 2757a5516438SAndi Kleen h->surplus_huge_pages, 2758a5516438SAndi Kleen 1UL << (huge_page_order(h) + PAGE_SHIFT - 10)); 27591da177e4SLinus Torvalds } 27601da177e4SLinus Torvalds 27611da177e4SLinus Torvalds int hugetlb_report_node_meminfo(int nid, char *buf) 27621da177e4SLinus Torvalds { 2763a5516438SAndi Kleen struct hstate *h = &default_hstate; 2764457c1b27SNishanth Aravamudan if (!hugepages_supported()) 2765457c1b27SNishanth Aravamudan return 0; 27661da177e4SLinus Torvalds return sprintf(buf, 27671da177e4SLinus Torvalds "Node %d HugePages_Total: %5u\n" 2768a1de0919SNishanth Aravamudan "Node %d HugePages_Free: %5u\n" 2769a1de0919SNishanth Aravamudan "Node %d HugePages_Surp: %5u\n", 2770a5516438SAndi Kleen nid, h->nr_huge_pages_node[nid], 2771a5516438SAndi Kleen nid, h->free_huge_pages_node[nid], 2772a5516438SAndi Kleen nid, h->surplus_huge_pages_node[nid]); 27731da177e4SLinus Torvalds } 27741da177e4SLinus Torvalds 2775949f7ec5SDavid Rientjes void hugetlb_show_meminfo(void) 2776949f7ec5SDavid Rientjes { 2777949f7ec5SDavid Rientjes struct hstate *h; 2778949f7ec5SDavid Rientjes int nid; 2779949f7ec5SDavid Rientjes 2780457c1b27SNishanth Aravamudan if (!hugepages_supported()) 2781457c1b27SNishanth Aravamudan return; 2782457c1b27SNishanth Aravamudan 2783949f7ec5SDavid Rientjes for_each_node_state(nid, N_MEMORY) 2784949f7ec5SDavid Rientjes for_each_hstate(h) 2785949f7ec5SDavid Rientjes pr_info("Node %d hugepages_total=%u hugepages_free=%u hugepages_surp=%u hugepages_size=%lukB\n", 2786949f7ec5SDavid Rientjes nid, 2787949f7ec5SDavid Rientjes h->nr_huge_pages_node[nid], 2788949f7ec5SDavid Rientjes h->free_huge_pages_node[nid], 2789949f7ec5SDavid Rientjes h->surplus_huge_pages_node[nid], 2790949f7ec5SDavid Rientjes 1UL << (huge_page_order(h) + PAGE_SHIFT - 10)); 2791949f7ec5SDavid Rientjes } 2792949f7ec5SDavid Rientjes 27931da177e4SLinus Torvalds /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ 27941da177e4SLinus Torvalds unsigned long hugetlb_total_pages(void) 27951da177e4SLinus Torvalds { 2796d0028588SWanpeng Li struct hstate *h; 2797d0028588SWanpeng Li unsigned long nr_total_pages = 0; 2798d0028588SWanpeng Li 2799d0028588SWanpeng Li for_each_hstate(h) 2800d0028588SWanpeng Li nr_total_pages += h->nr_huge_pages * pages_per_huge_page(h); 2801d0028588SWanpeng Li return nr_total_pages; 28021da177e4SLinus Torvalds } 28031da177e4SLinus Torvalds 2804a5516438SAndi Kleen static int hugetlb_acct_memory(struct hstate *h, long delta) 2805fc1b8a73SMel Gorman { 2806fc1b8a73SMel Gorman int ret = -ENOMEM; 2807fc1b8a73SMel Gorman 2808fc1b8a73SMel Gorman spin_lock(&hugetlb_lock); 2809fc1b8a73SMel Gorman /* 2810fc1b8a73SMel Gorman * When cpuset is configured, it breaks the strict hugetlb page 2811fc1b8a73SMel Gorman * reservation as the accounting is done on a global variable. Such 2812fc1b8a73SMel Gorman * reservation is completely rubbish in the presence of cpuset because 2813fc1b8a73SMel Gorman * the reservation is not checked against page availability for the 2814fc1b8a73SMel Gorman * current cpuset. Application can still potentially OOM'ed by kernel 2815fc1b8a73SMel Gorman * with lack of free htlb page in cpuset that the task is in. 2816fc1b8a73SMel Gorman * Attempt to enforce strict accounting with cpuset is almost 2817fc1b8a73SMel Gorman * impossible (or too ugly) because cpuset is too fluid that 2818fc1b8a73SMel Gorman * task or memory node can be dynamically moved between cpusets. 2819fc1b8a73SMel Gorman * 2820fc1b8a73SMel Gorman * The change of semantics for shared hugetlb mapping with cpuset is 2821fc1b8a73SMel Gorman * undesirable. However, in order to preserve some of the semantics, 2822fc1b8a73SMel Gorman * we fall back to check against current free page availability as 2823fc1b8a73SMel Gorman * a best attempt and hopefully to minimize the impact of changing 2824fc1b8a73SMel Gorman * semantics that cpuset has. 2825fc1b8a73SMel Gorman */ 2826fc1b8a73SMel Gorman if (delta > 0) { 2827a5516438SAndi Kleen if (gather_surplus_pages(h, delta) < 0) 2828fc1b8a73SMel Gorman goto out; 2829fc1b8a73SMel Gorman 2830a5516438SAndi Kleen if (delta > cpuset_mems_nr(h->free_huge_pages_node)) { 2831a5516438SAndi Kleen return_unused_surplus_pages(h, delta); 2832fc1b8a73SMel Gorman goto out; 2833fc1b8a73SMel Gorman } 2834fc1b8a73SMel Gorman } 2835fc1b8a73SMel Gorman 2836fc1b8a73SMel Gorman ret = 0; 2837fc1b8a73SMel Gorman if (delta < 0) 2838a5516438SAndi Kleen return_unused_surplus_pages(h, (unsigned long) -delta); 2839fc1b8a73SMel Gorman 2840fc1b8a73SMel Gorman out: 2841fc1b8a73SMel Gorman spin_unlock(&hugetlb_lock); 2842fc1b8a73SMel Gorman return ret; 2843fc1b8a73SMel Gorman } 2844fc1b8a73SMel Gorman 284584afd99bSAndy Whitcroft static void hugetlb_vm_op_open(struct vm_area_struct *vma) 284684afd99bSAndy Whitcroft { 2847f522c3acSJoonsoo Kim struct resv_map *resv = vma_resv_map(vma); 284884afd99bSAndy Whitcroft 284984afd99bSAndy Whitcroft /* 285084afd99bSAndy Whitcroft * This new VMA should share its siblings reservation map if present. 285184afd99bSAndy Whitcroft * The VMA will only ever have a valid reservation map pointer where 285284afd99bSAndy Whitcroft * it is being copied for another still existing VMA. As that VMA 285325985edcSLucas De Marchi * has a reference to the reservation map it cannot disappear until 285484afd99bSAndy Whitcroft * after this open call completes. It is therefore safe to take a 285584afd99bSAndy Whitcroft * new reference here without additional locking. 285684afd99bSAndy Whitcroft */ 28574e35f483SJoonsoo Kim if (resv && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) 2858f522c3acSJoonsoo Kim kref_get(&resv->refs); 285984afd99bSAndy Whitcroft } 286084afd99bSAndy Whitcroft 2861a1e78772SMel Gorman static void hugetlb_vm_op_close(struct vm_area_struct *vma) 2862a1e78772SMel Gorman { 2863a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 2864f522c3acSJoonsoo Kim struct resv_map *resv = vma_resv_map(vma); 286590481622SDavid Gibson struct hugepage_subpool *spool = subpool_vma(vma); 28664e35f483SJoonsoo Kim unsigned long reserve, start, end; 28671c5ecae3SMike Kravetz long gbl_reserve; 286884afd99bSAndy Whitcroft 28694e35f483SJoonsoo Kim if (!resv || !is_vma_resv_set(vma, HPAGE_RESV_OWNER)) 28704e35f483SJoonsoo Kim return; 28714e35f483SJoonsoo Kim 2872a5516438SAndi Kleen start = vma_hugecache_offset(h, vma, vma->vm_start); 2873a5516438SAndi Kleen end = vma_hugecache_offset(h, vma, vma->vm_end); 287484afd99bSAndy Whitcroft 28754e35f483SJoonsoo Kim reserve = (end - start) - region_count(resv, start, end); 287684afd99bSAndy Whitcroft 2877f031dd27SJoonsoo Kim kref_put(&resv->refs, resv_map_release); 287884afd99bSAndy Whitcroft 28797251ff78SAdam Litke if (reserve) { 28801c5ecae3SMike Kravetz /* 28811c5ecae3SMike Kravetz * Decrement reserve counts. The global reserve count may be 28821c5ecae3SMike Kravetz * adjusted if the subpool has a minimum size. 28831c5ecae3SMike Kravetz */ 28841c5ecae3SMike Kravetz gbl_reserve = hugepage_subpool_put_pages(spool, reserve); 28851c5ecae3SMike Kravetz hugetlb_acct_memory(h, -gbl_reserve); 28867251ff78SAdam Litke } 2887a1e78772SMel Gorman } 2888a1e78772SMel Gorman 28891da177e4SLinus Torvalds /* 28901da177e4SLinus Torvalds * We cannot handle pagefaults against hugetlb pages at all. They cause 28911da177e4SLinus Torvalds * handle_mm_fault() to try to instantiate regular-sized pages in the 28921da177e4SLinus Torvalds * hugegpage VMA. do_page_fault() is supposed to trap this, so BUG is we get 28931da177e4SLinus Torvalds * this far. 28941da177e4SLinus Torvalds */ 2895d0217ac0SNick Piggin static int hugetlb_vm_op_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 28961da177e4SLinus Torvalds { 28971da177e4SLinus Torvalds BUG(); 2898d0217ac0SNick Piggin return 0; 28991da177e4SLinus Torvalds } 29001da177e4SLinus Torvalds 2901f0f37e2fSAlexey Dobriyan const struct vm_operations_struct hugetlb_vm_ops = { 2902d0217ac0SNick Piggin .fault = hugetlb_vm_op_fault, 290384afd99bSAndy Whitcroft .open = hugetlb_vm_op_open, 2904a1e78772SMel Gorman .close = hugetlb_vm_op_close, 29051da177e4SLinus Torvalds }; 29061da177e4SLinus Torvalds 29071e8f889bSDavid Gibson static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, 29081e8f889bSDavid Gibson int writable) 290963551ae0SDavid Gibson { 291063551ae0SDavid Gibson pte_t entry; 291163551ae0SDavid Gibson 29121e8f889bSDavid Gibson if (writable) { 2913106c992aSGerald Schaefer entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page, 2914106c992aSGerald Schaefer vma->vm_page_prot))); 291563551ae0SDavid Gibson } else { 2916106c992aSGerald Schaefer entry = huge_pte_wrprotect(mk_huge_pte(page, 2917106c992aSGerald Schaefer vma->vm_page_prot)); 291863551ae0SDavid Gibson } 291963551ae0SDavid Gibson entry = pte_mkyoung(entry); 292063551ae0SDavid Gibson entry = pte_mkhuge(entry); 2921d9ed9faaSChris Metcalf entry = arch_make_huge_pte(entry, vma, page, writable); 292263551ae0SDavid Gibson 292363551ae0SDavid Gibson return entry; 292463551ae0SDavid Gibson } 292563551ae0SDavid Gibson 29261e8f889bSDavid Gibson static void set_huge_ptep_writable(struct vm_area_struct *vma, 29271e8f889bSDavid Gibson unsigned long address, pte_t *ptep) 29281e8f889bSDavid Gibson { 29291e8f889bSDavid Gibson pte_t entry; 29301e8f889bSDavid Gibson 2931106c992aSGerald Schaefer entry = huge_pte_mkwrite(huge_pte_mkdirty(huge_ptep_get(ptep))); 293232f84528SChris Forbes if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) 29334b3073e1SRussell King update_mmu_cache(vma, address, ptep); 29341e8f889bSDavid Gibson } 29351e8f889bSDavid Gibson 29364a705fefSNaoya Horiguchi static int is_hugetlb_entry_migration(pte_t pte) 29374a705fefSNaoya Horiguchi { 29384a705fefSNaoya Horiguchi swp_entry_t swp; 29394a705fefSNaoya Horiguchi 29404a705fefSNaoya Horiguchi if (huge_pte_none(pte) || pte_present(pte)) 29414a705fefSNaoya Horiguchi return 0; 29424a705fefSNaoya Horiguchi swp = pte_to_swp_entry(pte); 29434a705fefSNaoya Horiguchi if (non_swap_entry(swp) && is_migration_entry(swp)) 29444a705fefSNaoya Horiguchi return 1; 29454a705fefSNaoya Horiguchi else 29464a705fefSNaoya Horiguchi return 0; 29474a705fefSNaoya Horiguchi } 29484a705fefSNaoya Horiguchi 29494a705fefSNaoya Horiguchi static int is_hugetlb_entry_hwpoisoned(pte_t pte) 29504a705fefSNaoya Horiguchi { 29514a705fefSNaoya Horiguchi swp_entry_t swp; 29524a705fefSNaoya Horiguchi 29534a705fefSNaoya Horiguchi if (huge_pte_none(pte) || pte_present(pte)) 29544a705fefSNaoya Horiguchi return 0; 29554a705fefSNaoya Horiguchi swp = pte_to_swp_entry(pte); 29564a705fefSNaoya Horiguchi if (non_swap_entry(swp) && is_hwpoison_entry(swp)) 29574a705fefSNaoya Horiguchi return 1; 29584a705fefSNaoya Horiguchi else 29594a705fefSNaoya Horiguchi return 0; 29604a705fefSNaoya Horiguchi } 29611e8f889bSDavid Gibson 296263551ae0SDavid Gibson int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, 296363551ae0SDavid Gibson struct vm_area_struct *vma) 296463551ae0SDavid Gibson { 296563551ae0SDavid Gibson pte_t *src_pte, *dst_pte, entry; 296663551ae0SDavid Gibson struct page *ptepage; 29671c59827dSHugh Dickins unsigned long addr; 29681e8f889bSDavid Gibson int cow; 2969a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 2970a5516438SAndi Kleen unsigned long sz = huge_page_size(h); 2971e8569dd2SAndreas Sandberg unsigned long mmun_start; /* For mmu_notifiers */ 2972e8569dd2SAndreas Sandberg unsigned long mmun_end; /* For mmu_notifiers */ 2973e8569dd2SAndreas Sandberg int ret = 0; 29741e8f889bSDavid Gibson 29751e8f889bSDavid Gibson cow = (vma->vm_flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE; 297663551ae0SDavid Gibson 2977e8569dd2SAndreas Sandberg mmun_start = vma->vm_start; 2978e8569dd2SAndreas Sandberg mmun_end = vma->vm_end; 2979e8569dd2SAndreas Sandberg if (cow) 2980e8569dd2SAndreas Sandberg mmu_notifier_invalidate_range_start(src, mmun_start, mmun_end); 2981e8569dd2SAndreas Sandberg 2982a5516438SAndi Kleen for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) { 2983cb900f41SKirill A. Shutemov spinlock_t *src_ptl, *dst_ptl; 2984c74df32cSHugh Dickins src_pte = huge_pte_offset(src, addr); 2985c74df32cSHugh Dickins if (!src_pte) 2986c74df32cSHugh Dickins continue; 2987a5516438SAndi Kleen dst_pte = huge_pte_alloc(dst, addr, sz); 2988e8569dd2SAndreas Sandberg if (!dst_pte) { 2989e8569dd2SAndreas Sandberg ret = -ENOMEM; 2990e8569dd2SAndreas Sandberg break; 2991e8569dd2SAndreas Sandberg } 2992c5c99429SLarry Woodman 2993c5c99429SLarry Woodman /* If the pagetables are shared don't copy or take references */ 2994c5c99429SLarry Woodman if (dst_pte == src_pte) 2995c5c99429SLarry Woodman continue; 2996c5c99429SLarry Woodman 2997cb900f41SKirill A. Shutemov dst_ptl = huge_pte_lock(h, dst, dst_pte); 2998cb900f41SKirill A. Shutemov src_ptl = huge_pte_lockptr(h, src, src_pte); 2999cb900f41SKirill A. Shutemov spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); 30004a705fefSNaoya Horiguchi entry = huge_ptep_get(src_pte); 30014a705fefSNaoya Horiguchi if (huge_pte_none(entry)) { /* skip none entry */ 30024a705fefSNaoya Horiguchi ; 30034a705fefSNaoya Horiguchi } else if (unlikely(is_hugetlb_entry_migration(entry) || 30044a705fefSNaoya Horiguchi is_hugetlb_entry_hwpoisoned(entry))) { 30054a705fefSNaoya Horiguchi swp_entry_t swp_entry = pte_to_swp_entry(entry); 30064a705fefSNaoya Horiguchi 30074a705fefSNaoya Horiguchi if (is_write_migration_entry(swp_entry) && cow) { 30084a705fefSNaoya Horiguchi /* 30094a705fefSNaoya Horiguchi * COW mappings require pages in both 30104a705fefSNaoya Horiguchi * parent and child to be set to read. 30114a705fefSNaoya Horiguchi */ 30124a705fefSNaoya Horiguchi make_migration_entry_read(&swp_entry); 30134a705fefSNaoya Horiguchi entry = swp_entry_to_pte(swp_entry); 30144a705fefSNaoya Horiguchi set_huge_pte_at(src, addr, src_pte, entry); 30154a705fefSNaoya Horiguchi } 30164a705fefSNaoya Horiguchi set_huge_pte_at(dst, addr, dst_pte, entry); 30174a705fefSNaoya Horiguchi } else { 301834ee645eSJoerg Roedel if (cow) { 30197f2e9525SGerald Schaefer huge_ptep_set_wrprotect(src, addr, src_pte); 302034ee645eSJoerg Roedel mmu_notifier_invalidate_range(src, mmun_start, 302134ee645eSJoerg Roedel mmun_end); 302234ee645eSJoerg Roedel } 30230253d634SNaoya Horiguchi entry = huge_ptep_get(src_pte); 302463551ae0SDavid Gibson ptepage = pte_page(entry); 302563551ae0SDavid Gibson get_page(ptepage); 30260fe6e20bSNaoya Horiguchi page_dup_rmap(ptepage); 302763551ae0SDavid Gibson set_huge_pte_at(dst, addr, dst_pte, entry); 30281c59827dSHugh Dickins } 3029cb900f41SKirill A. Shutemov spin_unlock(src_ptl); 3030cb900f41SKirill A. Shutemov spin_unlock(dst_ptl); 303163551ae0SDavid Gibson } 303263551ae0SDavid Gibson 3033e8569dd2SAndreas Sandberg if (cow) 3034e8569dd2SAndreas Sandberg mmu_notifier_invalidate_range_end(src, mmun_start, mmun_end); 3035e8569dd2SAndreas Sandberg 3036e8569dd2SAndreas Sandberg return ret; 303763551ae0SDavid Gibson } 303863551ae0SDavid Gibson 303924669e58SAneesh Kumar K.V void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 304024669e58SAneesh Kumar K.V unsigned long start, unsigned long end, 304124669e58SAneesh Kumar K.V struct page *ref_page) 304263551ae0SDavid Gibson { 304324669e58SAneesh Kumar K.V int force_flush = 0; 304463551ae0SDavid Gibson struct mm_struct *mm = vma->vm_mm; 304563551ae0SDavid Gibson unsigned long address; 3046c7546f8fSDavid Gibson pte_t *ptep; 304763551ae0SDavid Gibson pte_t pte; 3048cb900f41SKirill A. Shutemov spinlock_t *ptl; 304963551ae0SDavid Gibson struct page *page; 3050a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 3051a5516438SAndi Kleen unsigned long sz = huge_page_size(h); 30522ec74c3eSSagi Grimberg const unsigned long mmun_start = start; /* For mmu_notifiers */ 30532ec74c3eSSagi Grimberg const unsigned long mmun_end = end; /* For mmu_notifiers */ 3054a5516438SAndi Kleen 305563551ae0SDavid Gibson WARN_ON(!is_vm_hugetlb_page(vma)); 3056a5516438SAndi Kleen BUG_ON(start & ~huge_page_mask(h)); 3057a5516438SAndi Kleen BUG_ON(end & ~huge_page_mask(h)); 305863551ae0SDavid Gibson 305924669e58SAneesh Kumar K.V tlb_start_vma(tlb, vma); 30602ec74c3eSSagi Grimberg mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); 3061569f48b8SHillf Danton address = start; 306224669e58SAneesh Kumar K.V again: 3063569f48b8SHillf Danton for (; address < end; address += sz) { 3064c7546f8fSDavid Gibson ptep = huge_pte_offset(mm, address); 3065c7546f8fSDavid Gibson if (!ptep) 3066c7546f8fSDavid Gibson continue; 3067c7546f8fSDavid Gibson 3068cb900f41SKirill A. Shutemov ptl = huge_pte_lock(h, mm, ptep); 306939dde65cSChen, Kenneth W if (huge_pmd_unshare(mm, &address, ptep)) 3070cb900f41SKirill A. Shutemov goto unlock; 307139dde65cSChen, Kenneth W 30726629326bSHillf Danton pte = huge_ptep_get(ptep); 30736629326bSHillf Danton if (huge_pte_none(pte)) 3074cb900f41SKirill A. Shutemov goto unlock; 30756629326bSHillf Danton 30766629326bSHillf Danton /* 30779fbc1f63SNaoya Horiguchi * Migrating hugepage or HWPoisoned hugepage is already 30789fbc1f63SNaoya Horiguchi * unmapped and its refcount is dropped, so just clear pte here. 30796629326bSHillf Danton */ 30809fbc1f63SNaoya Horiguchi if (unlikely(!pte_present(pte))) { 3081106c992aSGerald Schaefer huge_pte_clear(mm, address, ptep); 3082cb900f41SKirill A. Shutemov goto unlock; 30838c4894c6SNaoya Horiguchi } 30846629326bSHillf Danton 30856629326bSHillf Danton page = pte_page(pte); 308604f2cbe3SMel Gorman /* 308704f2cbe3SMel Gorman * If a reference page is supplied, it is because a specific 308804f2cbe3SMel Gorman * page is being unmapped, not a range. Ensure the page we 308904f2cbe3SMel Gorman * are about to unmap is the actual page of interest. 309004f2cbe3SMel Gorman */ 309104f2cbe3SMel Gorman if (ref_page) { 309204f2cbe3SMel Gorman if (page != ref_page) 3093cb900f41SKirill A. Shutemov goto unlock; 309404f2cbe3SMel Gorman 309504f2cbe3SMel Gorman /* 309604f2cbe3SMel Gorman * Mark the VMA as having unmapped its page so that 309704f2cbe3SMel Gorman * future faults in this VMA will fail rather than 309804f2cbe3SMel Gorman * looking like data was lost 309904f2cbe3SMel Gorman */ 310004f2cbe3SMel Gorman set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED); 310104f2cbe3SMel Gorman } 310204f2cbe3SMel Gorman 3103c7546f8fSDavid Gibson pte = huge_ptep_get_and_clear(mm, address, ptep); 310424669e58SAneesh Kumar K.V tlb_remove_tlb_entry(tlb, ptep, address); 3105106c992aSGerald Schaefer if (huge_pte_dirty(pte)) 31066649a386SKen Chen set_page_dirty(page); 31079e81130bSHillf Danton 310824669e58SAneesh Kumar K.V page_remove_rmap(page); 310924669e58SAneesh Kumar K.V force_flush = !__tlb_remove_page(tlb, page); 3110cb900f41SKirill A. Shutemov if (force_flush) { 3111569f48b8SHillf Danton address += sz; 3112cb900f41SKirill A. Shutemov spin_unlock(ptl); 31139e81130bSHillf Danton break; 311463551ae0SDavid Gibson } 3115cb900f41SKirill A. Shutemov /* Bail out after unmapping reference page if supplied */ 3116cb900f41SKirill A. Shutemov if (ref_page) { 3117cb900f41SKirill A. Shutemov spin_unlock(ptl); 3118cb900f41SKirill A. Shutemov break; 3119cb900f41SKirill A. Shutemov } 3120cb900f41SKirill A. Shutemov unlock: 3121cb900f41SKirill A. Shutemov spin_unlock(ptl); 3122cb900f41SKirill A. Shutemov } 312324669e58SAneesh Kumar K.V /* 312424669e58SAneesh Kumar K.V * mmu_gather ran out of room to batch pages, we break out of 312524669e58SAneesh Kumar K.V * the PTE lock to avoid doing the potential expensive TLB invalidate 312624669e58SAneesh Kumar K.V * and page-free while holding it. 312724669e58SAneesh Kumar K.V */ 312824669e58SAneesh Kumar K.V if (force_flush) { 312924669e58SAneesh Kumar K.V force_flush = 0; 313024669e58SAneesh Kumar K.V tlb_flush_mmu(tlb); 313124669e58SAneesh Kumar K.V if (address < end && !ref_page) 313224669e58SAneesh Kumar K.V goto again; 3133fe1668aeSChen, Kenneth W } 31342ec74c3eSSagi Grimberg mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); 313524669e58SAneesh Kumar K.V tlb_end_vma(tlb, vma); 31361da177e4SLinus Torvalds } 313763551ae0SDavid Gibson 3138d833352aSMel Gorman void __unmap_hugepage_range_final(struct mmu_gather *tlb, 3139d833352aSMel Gorman struct vm_area_struct *vma, unsigned long start, 3140d833352aSMel Gorman unsigned long end, struct page *ref_page) 3141d833352aSMel Gorman { 3142d833352aSMel Gorman __unmap_hugepage_range(tlb, vma, start, end, ref_page); 3143d833352aSMel Gorman 3144d833352aSMel Gorman /* 3145d833352aSMel Gorman * Clear this flag so that x86's huge_pmd_share page_table_shareable 3146d833352aSMel Gorman * test will fail on a vma being torn down, and not grab a page table 3147d833352aSMel Gorman * on its way out. We're lucky that the flag has such an appropriate 3148d833352aSMel Gorman * name, and can in fact be safely cleared here. We could clear it 3149d833352aSMel Gorman * before the __unmap_hugepage_range above, but all that's necessary 3150c8c06efaSDavidlohr Bueso * is to clear it before releasing the i_mmap_rwsem. This works 3151d833352aSMel Gorman * because in the context this is called, the VMA is about to be 3152c8c06efaSDavidlohr Bueso * destroyed and the i_mmap_rwsem is held. 3153d833352aSMel Gorman */ 3154d833352aSMel Gorman vma->vm_flags &= ~VM_MAYSHARE; 3155d833352aSMel Gorman } 3156d833352aSMel Gorman 3157502717f4SChen, Kenneth W void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, 315804f2cbe3SMel Gorman unsigned long end, struct page *ref_page) 3159502717f4SChen, Kenneth W { 316024669e58SAneesh Kumar K.V struct mm_struct *mm; 316124669e58SAneesh Kumar K.V struct mmu_gather tlb; 316224669e58SAneesh Kumar K.V 316324669e58SAneesh Kumar K.V mm = vma->vm_mm; 316424669e58SAneesh Kumar K.V 31652b047252SLinus Torvalds tlb_gather_mmu(&tlb, mm, start, end); 316624669e58SAneesh Kumar K.V __unmap_hugepage_range(&tlb, vma, start, end, ref_page); 316724669e58SAneesh Kumar K.V tlb_finish_mmu(&tlb, start, end); 3168502717f4SChen, Kenneth W } 3169502717f4SChen, Kenneth W 317004f2cbe3SMel Gorman /* 317104f2cbe3SMel Gorman * This is called when the original mapper is failing to COW a MAP_PRIVATE 317204f2cbe3SMel Gorman * mappping it owns the reserve page for. The intention is to unmap the page 317304f2cbe3SMel Gorman * from other VMAs and let the children be SIGKILLed if they are faulting the 317404f2cbe3SMel Gorman * same region. 317504f2cbe3SMel Gorman */ 31762f4612afSDavidlohr Bueso static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, 31772a4b3dedSHarvey Harrison struct page *page, unsigned long address) 317804f2cbe3SMel Gorman { 31797526674dSAdam Litke struct hstate *h = hstate_vma(vma); 318004f2cbe3SMel Gorman struct vm_area_struct *iter_vma; 318104f2cbe3SMel Gorman struct address_space *mapping; 318204f2cbe3SMel Gorman pgoff_t pgoff; 318304f2cbe3SMel Gorman 318404f2cbe3SMel Gorman /* 318504f2cbe3SMel Gorman * vm_pgoff is in PAGE_SIZE units, hence the different calculation 318604f2cbe3SMel Gorman * from page cache lookup which is in HPAGE_SIZE units. 318704f2cbe3SMel Gorman */ 31887526674dSAdam Litke address = address & huge_page_mask(h); 318936e4f20aSMichal Hocko pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + 319036e4f20aSMichal Hocko vma->vm_pgoff; 3191496ad9aaSAl Viro mapping = file_inode(vma->vm_file)->i_mapping; 319204f2cbe3SMel Gorman 31934eb2b1dcSMel Gorman /* 31944eb2b1dcSMel Gorman * Take the mapping lock for the duration of the table walk. As 31954eb2b1dcSMel Gorman * this mapping should be shared between all the VMAs, 31964eb2b1dcSMel Gorman * __unmap_hugepage_range() is called as the lock is already held 31974eb2b1dcSMel Gorman */ 319883cde9e8SDavidlohr Bueso i_mmap_lock_write(mapping); 31996b2dbba8SMichel Lespinasse vma_interval_tree_foreach(iter_vma, &mapping->i_mmap, pgoff, pgoff) { 320004f2cbe3SMel Gorman /* Do not unmap the current VMA */ 320104f2cbe3SMel Gorman if (iter_vma == vma) 320204f2cbe3SMel Gorman continue; 320304f2cbe3SMel Gorman 320404f2cbe3SMel Gorman /* 32052f84a899SMel Gorman * Shared VMAs have their own reserves and do not affect 32062f84a899SMel Gorman * MAP_PRIVATE accounting but it is possible that a shared 32072f84a899SMel Gorman * VMA is using the same page so check and skip such VMAs. 32082f84a899SMel Gorman */ 32092f84a899SMel Gorman if (iter_vma->vm_flags & VM_MAYSHARE) 32102f84a899SMel Gorman continue; 32112f84a899SMel Gorman 32122f84a899SMel Gorman /* 321304f2cbe3SMel Gorman * Unmap the page from other VMAs without their own reserves. 321404f2cbe3SMel Gorman * They get marked to be SIGKILLed if they fault in these 321504f2cbe3SMel Gorman * areas. This is because a future no-page fault on this VMA 321604f2cbe3SMel Gorman * could insert a zeroed page instead of the data existing 321704f2cbe3SMel Gorman * from the time of fork. This would look like data corruption 321804f2cbe3SMel Gorman */ 321904f2cbe3SMel Gorman if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER)) 322024669e58SAneesh Kumar K.V unmap_hugepage_range(iter_vma, address, 322124669e58SAneesh Kumar K.V address + huge_page_size(h), page); 322204f2cbe3SMel Gorman } 322383cde9e8SDavidlohr Bueso i_mmap_unlock_write(mapping); 322404f2cbe3SMel Gorman } 322504f2cbe3SMel Gorman 32260fe6e20bSNaoya Horiguchi /* 32270fe6e20bSNaoya Horiguchi * Hugetlb_cow() should be called with page lock of the original hugepage held. 3228ef009b25SMichal Hocko * Called with hugetlb_instantiation_mutex held and pte_page locked so we 3229ef009b25SMichal Hocko * cannot race with other handlers or page migration. 3230ef009b25SMichal Hocko * Keep the pte_same checks anyway to make transition from the mutex easier. 32310fe6e20bSNaoya Horiguchi */ 32321e8f889bSDavid Gibson static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, 323304f2cbe3SMel Gorman unsigned long address, pte_t *ptep, pte_t pte, 3234cb900f41SKirill A. Shutemov struct page *pagecache_page, spinlock_t *ptl) 32351e8f889bSDavid Gibson { 3236a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 32371e8f889bSDavid Gibson struct page *old_page, *new_page; 3238ad4404a2SDavidlohr Bueso int ret = 0, outside_reserve = 0; 32392ec74c3eSSagi Grimberg unsigned long mmun_start; /* For mmu_notifiers */ 32402ec74c3eSSagi Grimberg unsigned long mmun_end; /* For mmu_notifiers */ 32411e8f889bSDavid Gibson 32421e8f889bSDavid Gibson old_page = pte_page(pte); 32431e8f889bSDavid Gibson 324404f2cbe3SMel Gorman retry_avoidcopy: 32451e8f889bSDavid Gibson /* If no-one else is actually using this page, avoid the copy 32461e8f889bSDavid Gibson * and just make the page writable */ 324737a2140dSJoonsoo Kim if (page_mapcount(old_page) == 1 && PageAnon(old_page)) { 32480fe6e20bSNaoya Horiguchi page_move_anon_rmap(old_page, vma, address); 32491e8f889bSDavid Gibson set_huge_ptep_writable(vma, address, ptep); 325083c54070SNick Piggin return 0; 32511e8f889bSDavid Gibson } 32521e8f889bSDavid Gibson 325304f2cbe3SMel Gorman /* 325404f2cbe3SMel Gorman * If the process that created a MAP_PRIVATE mapping is about to 325504f2cbe3SMel Gorman * perform a COW due to a shared page count, attempt to satisfy 325604f2cbe3SMel Gorman * the allocation without using the existing reserves. The pagecache 325704f2cbe3SMel Gorman * page is used to determine if the reserve at this address was 325804f2cbe3SMel Gorman * consumed or not. If reserves were used, a partial faulted mapping 325904f2cbe3SMel Gorman * at the time of fork() could consume its reserves on COW instead 326004f2cbe3SMel Gorman * of the full address range. 326104f2cbe3SMel Gorman */ 32625944d011SJoonsoo Kim if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) && 326304f2cbe3SMel Gorman old_page != pagecache_page) 326404f2cbe3SMel Gorman outside_reserve = 1; 326504f2cbe3SMel Gorman 32661e8f889bSDavid Gibson page_cache_get(old_page); 3267b76c8cfbSLarry Woodman 3268ad4404a2SDavidlohr Bueso /* 3269ad4404a2SDavidlohr Bueso * Drop page table lock as buddy allocator may be called. It will 3270ad4404a2SDavidlohr Bueso * be acquired again before returning to the caller, as expected. 3271ad4404a2SDavidlohr Bueso */ 3272cb900f41SKirill A. Shutemov spin_unlock(ptl); 327304f2cbe3SMel Gorman new_page = alloc_huge_page(vma, address, outside_reserve); 32741e8f889bSDavid Gibson 32752fc39cecSAdam Litke if (IS_ERR(new_page)) { 327604f2cbe3SMel Gorman /* 327704f2cbe3SMel Gorman * If a process owning a MAP_PRIVATE mapping fails to COW, 327804f2cbe3SMel Gorman * it is due to references held by a child and an insufficient 327904f2cbe3SMel Gorman * huge page pool. To guarantee the original mappers 328004f2cbe3SMel Gorman * reliability, unmap the page from child processes. The child 328104f2cbe3SMel Gorman * may get SIGKILLed if it later faults. 328204f2cbe3SMel Gorman */ 328304f2cbe3SMel Gorman if (outside_reserve) { 3284ad4404a2SDavidlohr Bueso page_cache_release(old_page); 328504f2cbe3SMel Gorman BUG_ON(huge_pte_none(pte)); 32862f4612afSDavidlohr Bueso unmap_ref_private(mm, vma, old_page, address); 328704f2cbe3SMel Gorman BUG_ON(huge_pte_none(pte)); 3288cb900f41SKirill A. Shutemov spin_lock(ptl); 3289a734bcc8SHillf Danton ptep = huge_pte_offset(mm, address & huge_page_mask(h)); 3290a9af0c5dSNaoya Horiguchi if (likely(ptep && 3291a9af0c5dSNaoya Horiguchi pte_same(huge_ptep_get(ptep), pte))) 329204f2cbe3SMel Gorman goto retry_avoidcopy; 3293a734bcc8SHillf Danton /* 3294cb900f41SKirill A. Shutemov * race occurs while re-acquiring page table 3295cb900f41SKirill A. Shutemov * lock, and our job is done. 3296a734bcc8SHillf Danton */ 3297a734bcc8SHillf Danton return 0; 329804f2cbe3SMel Gorman } 329904f2cbe3SMel Gorman 3300ad4404a2SDavidlohr Bueso ret = (PTR_ERR(new_page) == -ENOMEM) ? 3301ad4404a2SDavidlohr Bueso VM_FAULT_OOM : VM_FAULT_SIGBUS; 3302ad4404a2SDavidlohr Bueso goto out_release_old; 33031e8f889bSDavid Gibson } 33041e8f889bSDavid Gibson 33050fe6e20bSNaoya Horiguchi /* 33060fe6e20bSNaoya Horiguchi * When the original hugepage is shared one, it does not have 33070fe6e20bSNaoya Horiguchi * anon_vma prepared. 33080fe6e20bSNaoya Horiguchi */ 330944e2aa93SDean Nelson if (unlikely(anon_vma_prepare(vma))) { 3310ad4404a2SDavidlohr Bueso ret = VM_FAULT_OOM; 3311ad4404a2SDavidlohr Bueso goto out_release_all; 331244e2aa93SDean Nelson } 33130fe6e20bSNaoya Horiguchi 331447ad8475SAndrea Arcangeli copy_user_huge_page(new_page, old_page, address, vma, 331547ad8475SAndrea Arcangeli pages_per_huge_page(h)); 33160ed361deSNick Piggin __SetPageUptodate(new_page); 3317bcc54222SNaoya Horiguchi set_page_huge_active(new_page); 33181e8f889bSDavid Gibson 33192ec74c3eSSagi Grimberg mmun_start = address & huge_page_mask(h); 33202ec74c3eSSagi Grimberg mmun_end = mmun_start + huge_page_size(h); 33212ec74c3eSSagi Grimberg mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); 3322ad4404a2SDavidlohr Bueso 3323b76c8cfbSLarry Woodman /* 3324cb900f41SKirill A. Shutemov * Retake the page table lock to check for racing updates 3325b76c8cfbSLarry Woodman * before the page tables are altered 3326b76c8cfbSLarry Woodman */ 3327cb900f41SKirill A. Shutemov spin_lock(ptl); 3328a5516438SAndi Kleen ptep = huge_pte_offset(mm, address & huge_page_mask(h)); 3329a9af0c5dSNaoya Horiguchi if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { 333007443a85SJoonsoo Kim ClearPagePrivate(new_page); 333107443a85SJoonsoo Kim 33321e8f889bSDavid Gibson /* Break COW */ 33338fe627ecSGerald Schaefer huge_ptep_clear_flush(vma, address, ptep); 333434ee645eSJoerg Roedel mmu_notifier_invalidate_range(mm, mmun_start, mmun_end); 33351e8f889bSDavid Gibson set_huge_pte_at(mm, address, ptep, 33361e8f889bSDavid Gibson make_huge_pte(vma, new_page, 1)); 33370fe6e20bSNaoya Horiguchi page_remove_rmap(old_page); 3338cd67f0d2SNaoya Horiguchi hugepage_add_new_anon_rmap(new_page, vma, address); 33391e8f889bSDavid Gibson /* Make the old page be freed below */ 33401e8f889bSDavid Gibson new_page = old_page; 33411e8f889bSDavid Gibson } 3342cb900f41SKirill A. Shutemov spin_unlock(ptl); 33432ec74c3eSSagi Grimberg mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); 3344ad4404a2SDavidlohr Bueso out_release_all: 33451e8f889bSDavid Gibson page_cache_release(new_page); 3346ad4404a2SDavidlohr Bueso out_release_old: 33471e8f889bSDavid Gibson page_cache_release(old_page); 33488312034fSJoonsoo Kim 3349ad4404a2SDavidlohr Bueso spin_lock(ptl); /* Caller expects lock to be held */ 3350ad4404a2SDavidlohr Bueso return ret; 33511e8f889bSDavid Gibson } 33521e8f889bSDavid Gibson 335304f2cbe3SMel Gorman /* Return the pagecache page at a given address within a VMA */ 3354a5516438SAndi Kleen static struct page *hugetlbfs_pagecache_page(struct hstate *h, 3355a5516438SAndi Kleen struct vm_area_struct *vma, unsigned long address) 335604f2cbe3SMel Gorman { 335704f2cbe3SMel Gorman struct address_space *mapping; 3358e7c4b0bfSAndy Whitcroft pgoff_t idx; 335904f2cbe3SMel Gorman 336004f2cbe3SMel Gorman mapping = vma->vm_file->f_mapping; 3361a5516438SAndi Kleen idx = vma_hugecache_offset(h, vma, address); 336204f2cbe3SMel Gorman 336304f2cbe3SMel Gorman return find_lock_page(mapping, idx); 336404f2cbe3SMel Gorman } 336504f2cbe3SMel Gorman 33663ae77f43SHugh Dickins /* 33673ae77f43SHugh Dickins * Return whether there is a pagecache page to back given address within VMA. 33683ae77f43SHugh Dickins * Caller follow_hugetlb_page() holds page_table_lock so we cannot lock_page. 33693ae77f43SHugh Dickins */ 33703ae77f43SHugh Dickins static bool hugetlbfs_pagecache_present(struct hstate *h, 33712a15efc9SHugh Dickins struct vm_area_struct *vma, unsigned long address) 33722a15efc9SHugh Dickins { 33732a15efc9SHugh Dickins struct address_space *mapping; 33742a15efc9SHugh Dickins pgoff_t idx; 33752a15efc9SHugh Dickins struct page *page; 33762a15efc9SHugh Dickins 33772a15efc9SHugh Dickins mapping = vma->vm_file->f_mapping; 33782a15efc9SHugh Dickins idx = vma_hugecache_offset(h, vma, address); 33792a15efc9SHugh Dickins 33802a15efc9SHugh Dickins page = find_get_page(mapping, idx); 33812a15efc9SHugh Dickins if (page) 33822a15efc9SHugh Dickins put_page(page); 33832a15efc9SHugh Dickins return page != NULL; 33842a15efc9SHugh Dickins } 33852a15efc9SHugh Dickins 3386ab76ad54SMike Kravetz int huge_add_to_page_cache(struct page *page, struct address_space *mapping, 3387ab76ad54SMike Kravetz pgoff_t idx) 3388ab76ad54SMike Kravetz { 3389ab76ad54SMike Kravetz struct inode *inode = mapping->host; 3390ab76ad54SMike Kravetz struct hstate *h = hstate_inode(inode); 3391ab76ad54SMike Kravetz int err = add_to_page_cache(page, mapping, idx, GFP_KERNEL); 3392ab76ad54SMike Kravetz 3393ab76ad54SMike Kravetz if (err) 3394ab76ad54SMike Kravetz return err; 3395ab76ad54SMike Kravetz ClearPagePrivate(page); 3396ab76ad54SMike Kravetz 3397ab76ad54SMike Kravetz spin_lock(&inode->i_lock); 3398ab76ad54SMike Kravetz inode->i_blocks += blocks_per_huge_page(h); 3399ab76ad54SMike Kravetz spin_unlock(&inode->i_lock); 3400ab76ad54SMike Kravetz return 0; 3401ab76ad54SMike Kravetz } 3402ab76ad54SMike Kravetz 3403a1ed3ddaSRobert P. J. Day static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma, 34048382d914SDavidlohr Bueso struct address_space *mapping, pgoff_t idx, 3405788c7df4SHugh Dickins unsigned long address, pte_t *ptep, unsigned int flags) 3406ac9b9c66SHugh Dickins { 3407a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 3408ac9b9c66SHugh Dickins int ret = VM_FAULT_SIGBUS; 3409409eb8c2SHillf Danton int anon_rmap = 0; 34104c887265SAdam Litke unsigned long size; 34114c887265SAdam Litke struct page *page; 34121e8f889bSDavid Gibson pte_t new_pte; 3413cb900f41SKirill A. Shutemov spinlock_t *ptl; 34144c887265SAdam Litke 341504f2cbe3SMel Gorman /* 341604f2cbe3SMel Gorman * Currently, we are forced to kill the process in the event the 341704f2cbe3SMel Gorman * original mapper has unmapped pages from the child due to a failed 341825985edcSLucas De Marchi * COW. Warn that such a situation has occurred as it may not be obvious 341904f2cbe3SMel Gorman */ 342004f2cbe3SMel Gorman if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) { 3421ffb22af5SAndrew Morton pr_warning("PID %d killed due to inadequate hugepage pool\n", 342204f2cbe3SMel Gorman current->pid); 342304f2cbe3SMel Gorman return ret; 342404f2cbe3SMel Gorman } 342504f2cbe3SMel Gorman 34264c887265SAdam Litke /* 34274c887265SAdam Litke * Use page lock to guard against racing truncation 34284c887265SAdam Litke * before we get page_table_lock. 34294c887265SAdam Litke */ 34306bda666aSChristoph Lameter retry: 34316bda666aSChristoph Lameter page = find_lock_page(mapping, idx); 34326bda666aSChristoph Lameter if (!page) { 3433a5516438SAndi Kleen size = i_size_read(mapping->host) >> huge_page_shift(h); 3434ebed4bfcSHugh Dickins if (idx >= size) 3435ebed4bfcSHugh Dickins goto out; 343604f2cbe3SMel Gorman page = alloc_huge_page(vma, address, 0); 34372fc39cecSAdam Litke if (IS_ERR(page)) { 343876dcee75SAneesh Kumar K.V ret = PTR_ERR(page); 343976dcee75SAneesh Kumar K.V if (ret == -ENOMEM) 344076dcee75SAneesh Kumar K.V ret = VM_FAULT_OOM; 344176dcee75SAneesh Kumar K.V else 344276dcee75SAneesh Kumar K.V ret = VM_FAULT_SIGBUS; 34436bda666aSChristoph Lameter goto out; 34446bda666aSChristoph Lameter } 344547ad8475SAndrea Arcangeli clear_huge_page(page, address, pages_per_huge_page(h)); 34460ed361deSNick Piggin __SetPageUptodate(page); 3447bcc54222SNaoya Horiguchi set_page_huge_active(page); 3448ac9b9c66SHugh Dickins 3449f83a275dSMel Gorman if (vma->vm_flags & VM_MAYSHARE) { 3450ab76ad54SMike Kravetz int err = huge_add_to_page_cache(page, mapping, idx); 34516bda666aSChristoph Lameter if (err) { 34526bda666aSChristoph Lameter put_page(page); 34536bda666aSChristoph Lameter if (err == -EEXIST) 34546bda666aSChristoph Lameter goto retry; 34556bda666aSChristoph Lameter goto out; 34566bda666aSChristoph Lameter } 345723be7468SMel Gorman } else { 34586bda666aSChristoph Lameter lock_page(page); 34590fe6e20bSNaoya Horiguchi if (unlikely(anon_vma_prepare(vma))) { 34600fe6e20bSNaoya Horiguchi ret = VM_FAULT_OOM; 34610fe6e20bSNaoya Horiguchi goto backout_unlocked; 346223be7468SMel Gorman } 3463409eb8c2SHillf Danton anon_rmap = 1; 34640fe6e20bSNaoya Horiguchi } 34650fe6e20bSNaoya Horiguchi } else { 346657303d80SAndy Whitcroft /* 3467998b4382SNaoya Horiguchi * If memory error occurs between mmap() and fault, some process 3468998b4382SNaoya Horiguchi * don't have hwpoisoned swap entry for errored virtual address. 3469998b4382SNaoya Horiguchi * So we need to block hugepage fault by PG_hwpoison bit check. 3470fd6a03edSNaoya Horiguchi */ 3471fd6a03edSNaoya Horiguchi if (unlikely(PageHWPoison(page))) { 3472aa50d3a7SAndi Kleen ret = VM_FAULT_HWPOISON | 3473972dc4deSAneesh Kumar K.V VM_FAULT_SET_HINDEX(hstate_index(h)); 3474fd6a03edSNaoya Horiguchi goto backout_unlocked; 34756bda666aSChristoph Lameter } 3476998b4382SNaoya Horiguchi } 34771e8f889bSDavid Gibson 347857303d80SAndy Whitcroft /* 347957303d80SAndy Whitcroft * If we are going to COW a private mapping later, we examine the 348057303d80SAndy Whitcroft * pending reservations for this page now. This will ensure that 348157303d80SAndy Whitcroft * any allocations necessary to record that reservation occur outside 348257303d80SAndy Whitcroft * the spinlock. 348357303d80SAndy Whitcroft */ 34845e911373SMike Kravetz if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { 34852b26736cSAndy Whitcroft if (vma_needs_reservation(h, vma, address) < 0) { 34862b26736cSAndy Whitcroft ret = VM_FAULT_OOM; 34872b26736cSAndy Whitcroft goto backout_unlocked; 34882b26736cSAndy Whitcroft } 34895e911373SMike Kravetz /* Just decrements count, does not deallocate */ 3490feba16e2SMike Kravetz vma_end_reservation(h, vma, address); 34915e911373SMike Kravetz } 349257303d80SAndy Whitcroft 3493cb900f41SKirill A. Shutemov ptl = huge_pte_lockptr(h, mm, ptep); 3494cb900f41SKirill A. Shutemov spin_lock(ptl); 3495a5516438SAndi Kleen size = i_size_read(mapping->host) >> huge_page_shift(h); 34964c887265SAdam Litke if (idx >= size) 34974c887265SAdam Litke goto backout; 34984c887265SAdam Litke 349983c54070SNick Piggin ret = 0; 35007f2e9525SGerald Schaefer if (!huge_pte_none(huge_ptep_get(ptep))) 35014c887265SAdam Litke goto backout; 35024c887265SAdam Litke 350307443a85SJoonsoo Kim if (anon_rmap) { 350407443a85SJoonsoo Kim ClearPagePrivate(page); 3505409eb8c2SHillf Danton hugepage_add_new_anon_rmap(page, vma, address); 3506ac714904SChoi Gi-yong } else 3507409eb8c2SHillf Danton page_dup_rmap(page); 35081e8f889bSDavid Gibson new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) 35091e8f889bSDavid Gibson && (vma->vm_flags & VM_SHARED))); 35101e8f889bSDavid Gibson set_huge_pte_at(mm, address, ptep, new_pte); 35111e8f889bSDavid Gibson 3512788c7df4SHugh Dickins if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { 35131e8f889bSDavid Gibson /* Optimization, do the COW without a second fault */ 3514cb900f41SKirill A. Shutemov ret = hugetlb_cow(mm, vma, address, ptep, new_pte, page, ptl); 35151e8f889bSDavid Gibson } 35161e8f889bSDavid Gibson 3517cb900f41SKirill A. Shutemov spin_unlock(ptl); 35184c887265SAdam Litke unlock_page(page); 35194c887265SAdam Litke out: 3520ac9b9c66SHugh Dickins return ret; 35214c887265SAdam Litke 35224c887265SAdam Litke backout: 3523cb900f41SKirill A. Shutemov spin_unlock(ptl); 35242b26736cSAndy Whitcroft backout_unlocked: 35254c887265SAdam Litke unlock_page(page); 35264c887265SAdam Litke put_page(page); 35274c887265SAdam Litke goto out; 3528ac9b9c66SHugh Dickins } 3529ac9b9c66SHugh Dickins 35308382d914SDavidlohr Bueso #ifdef CONFIG_SMP 3531c672c7f2SMike Kravetz u32 hugetlb_fault_mutex_hash(struct hstate *h, struct mm_struct *mm, 35328382d914SDavidlohr Bueso struct vm_area_struct *vma, 35338382d914SDavidlohr Bueso struct address_space *mapping, 35348382d914SDavidlohr Bueso pgoff_t idx, unsigned long address) 35358382d914SDavidlohr Bueso { 35368382d914SDavidlohr Bueso unsigned long key[2]; 35378382d914SDavidlohr Bueso u32 hash; 35388382d914SDavidlohr Bueso 35398382d914SDavidlohr Bueso if (vma->vm_flags & VM_SHARED) { 35408382d914SDavidlohr Bueso key[0] = (unsigned long) mapping; 35418382d914SDavidlohr Bueso key[1] = idx; 35428382d914SDavidlohr Bueso } else { 35438382d914SDavidlohr Bueso key[0] = (unsigned long) mm; 35448382d914SDavidlohr Bueso key[1] = address >> huge_page_shift(h); 35458382d914SDavidlohr Bueso } 35468382d914SDavidlohr Bueso 35478382d914SDavidlohr Bueso hash = jhash2((u32 *)&key, sizeof(key)/sizeof(u32), 0); 35488382d914SDavidlohr Bueso 35498382d914SDavidlohr Bueso return hash & (num_fault_mutexes - 1); 35508382d914SDavidlohr Bueso } 35518382d914SDavidlohr Bueso #else 35528382d914SDavidlohr Bueso /* 35538382d914SDavidlohr Bueso * For uniprocesor systems we always use a single mutex, so just 35548382d914SDavidlohr Bueso * return 0 and avoid the hashing overhead. 35558382d914SDavidlohr Bueso */ 3556c672c7f2SMike Kravetz u32 hugetlb_fault_mutex_hash(struct hstate *h, struct mm_struct *mm, 35578382d914SDavidlohr Bueso struct vm_area_struct *vma, 35588382d914SDavidlohr Bueso struct address_space *mapping, 35598382d914SDavidlohr Bueso pgoff_t idx, unsigned long address) 35608382d914SDavidlohr Bueso { 35618382d914SDavidlohr Bueso return 0; 35628382d914SDavidlohr Bueso } 35638382d914SDavidlohr Bueso #endif 35648382d914SDavidlohr Bueso 356586e5216fSAdam Litke int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, 3566788c7df4SHugh Dickins unsigned long address, unsigned int flags) 356786e5216fSAdam Litke { 35688382d914SDavidlohr Bueso pte_t *ptep, entry; 3569cb900f41SKirill A. Shutemov spinlock_t *ptl; 35701e8f889bSDavid Gibson int ret; 35718382d914SDavidlohr Bueso u32 hash; 35728382d914SDavidlohr Bueso pgoff_t idx; 35730fe6e20bSNaoya Horiguchi struct page *page = NULL; 357457303d80SAndy Whitcroft struct page *pagecache_page = NULL; 3575a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 35768382d914SDavidlohr Bueso struct address_space *mapping; 35770f792cf9SNaoya Horiguchi int need_wait_lock = 0; 357886e5216fSAdam Litke 35791e16a539SKAMEZAWA Hiroyuki address &= huge_page_mask(h); 35801e16a539SKAMEZAWA Hiroyuki 3581fd6a03edSNaoya Horiguchi ptep = huge_pte_offset(mm, address); 3582fd6a03edSNaoya Horiguchi if (ptep) { 3583fd6a03edSNaoya Horiguchi entry = huge_ptep_get(ptep); 3584290408d4SNaoya Horiguchi if (unlikely(is_hugetlb_entry_migration(entry))) { 3585cb900f41SKirill A. Shutemov migration_entry_wait_huge(vma, mm, ptep); 3586290408d4SNaoya Horiguchi return 0; 3587290408d4SNaoya Horiguchi } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) 3588aa50d3a7SAndi Kleen return VM_FAULT_HWPOISON_LARGE | 3589972dc4deSAneesh Kumar K.V VM_FAULT_SET_HINDEX(hstate_index(h)); 3590fd6a03edSNaoya Horiguchi } 3591fd6a03edSNaoya Horiguchi 3592a5516438SAndi Kleen ptep = huge_pte_alloc(mm, address, huge_page_size(h)); 359386e5216fSAdam Litke if (!ptep) 359486e5216fSAdam Litke return VM_FAULT_OOM; 359586e5216fSAdam Litke 35968382d914SDavidlohr Bueso mapping = vma->vm_file->f_mapping; 35978382d914SDavidlohr Bueso idx = vma_hugecache_offset(h, vma, address); 35988382d914SDavidlohr Bueso 35993935baa9SDavid Gibson /* 36003935baa9SDavid Gibson * Serialize hugepage allocation and instantiation, so that we don't 36013935baa9SDavid Gibson * get spurious allocation failures if two CPUs race to instantiate 36023935baa9SDavid Gibson * the same page in the page cache. 36033935baa9SDavid Gibson */ 3604c672c7f2SMike Kravetz hash = hugetlb_fault_mutex_hash(h, mm, vma, mapping, idx, address); 3605c672c7f2SMike Kravetz mutex_lock(&hugetlb_fault_mutex_table[hash]); 36068382d914SDavidlohr Bueso 36077f2e9525SGerald Schaefer entry = huge_ptep_get(ptep); 36087f2e9525SGerald Schaefer if (huge_pte_none(entry)) { 36098382d914SDavidlohr Bueso ret = hugetlb_no_page(mm, vma, mapping, idx, address, ptep, flags); 3610b4d1d99fSDavid Gibson goto out_mutex; 36113935baa9SDavid Gibson } 361286e5216fSAdam Litke 361383c54070SNick Piggin ret = 0; 36141e8f889bSDavid Gibson 361557303d80SAndy Whitcroft /* 36160f792cf9SNaoya Horiguchi * entry could be a migration/hwpoison entry at this point, so this 36170f792cf9SNaoya Horiguchi * check prevents the kernel from going below assuming that we have 36180f792cf9SNaoya Horiguchi * a active hugepage in pagecache. This goto expects the 2nd page fault, 36190f792cf9SNaoya Horiguchi * and is_hugetlb_entry_(migration|hwpoisoned) check will properly 36200f792cf9SNaoya Horiguchi * handle it. 36210f792cf9SNaoya Horiguchi */ 36220f792cf9SNaoya Horiguchi if (!pte_present(entry)) 36230f792cf9SNaoya Horiguchi goto out_mutex; 36240f792cf9SNaoya Horiguchi 36250f792cf9SNaoya Horiguchi /* 362657303d80SAndy Whitcroft * If we are going to COW the mapping later, we examine the pending 362757303d80SAndy Whitcroft * reservations for this page now. This will ensure that any 362857303d80SAndy Whitcroft * allocations necessary to record that reservation occur outside the 362957303d80SAndy Whitcroft * spinlock. For private mappings, we also lookup the pagecache 363057303d80SAndy Whitcroft * page now as it is used to determine if a reservation has been 363157303d80SAndy Whitcroft * consumed. 363257303d80SAndy Whitcroft */ 3633106c992aSGerald Schaefer if ((flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) { 36342b26736cSAndy Whitcroft if (vma_needs_reservation(h, vma, address) < 0) { 36352b26736cSAndy Whitcroft ret = VM_FAULT_OOM; 3636b4d1d99fSDavid Gibson goto out_mutex; 36372b26736cSAndy Whitcroft } 36385e911373SMike Kravetz /* Just decrements count, does not deallocate */ 3639feba16e2SMike Kravetz vma_end_reservation(h, vma, address); 364057303d80SAndy Whitcroft 3641f83a275dSMel Gorman if (!(vma->vm_flags & VM_MAYSHARE)) 364257303d80SAndy Whitcroft pagecache_page = hugetlbfs_pagecache_page(h, 364357303d80SAndy Whitcroft vma, address); 364457303d80SAndy Whitcroft } 364557303d80SAndy Whitcroft 36460f792cf9SNaoya Horiguchi ptl = huge_pte_lock(h, mm, ptep); 36470fe6e20bSNaoya Horiguchi 36481e8f889bSDavid Gibson /* Check for a racing update before calling hugetlb_cow */ 3649b4d1d99fSDavid Gibson if (unlikely(!pte_same(entry, huge_ptep_get(ptep)))) 3650cb900f41SKirill A. Shutemov goto out_ptl; 3651b4d1d99fSDavid Gibson 36520f792cf9SNaoya Horiguchi /* 36530f792cf9SNaoya Horiguchi * hugetlb_cow() requires page locks of pte_page(entry) and 36540f792cf9SNaoya Horiguchi * pagecache_page, so here we need take the former one 36550f792cf9SNaoya Horiguchi * when page != pagecache_page or !pagecache_page. 36560f792cf9SNaoya Horiguchi */ 36570f792cf9SNaoya Horiguchi page = pte_page(entry); 36580f792cf9SNaoya Horiguchi if (page != pagecache_page) 36590f792cf9SNaoya Horiguchi if (!trylock_page(page)) { 36600f792cf9SNaoya Horiguchi need_wait_lock = 1; 36610f792cf9SNaoya Horiguchi goto out_ptl; 36620f792cf9SNaoya Horiguchi } 36630f792cf9SNaoya Horiguchi 36640f792cf9SNaoya Horiguchi get_page(page); 3665b4d1d99fSDavid Gibson 3666788c7df4SHugh Dickins if (flags & FAULT_FLAG_WRITE) { 3667106c992aSGerald Schaefer if (!huge_pte_write(entry)) { 366857303d80SAndy Whitcroft ret = hugetlb_cow(mm, vma, address, ptep, entry, 3669cb900f41SKirill A. Shutemov pagecache_page, ptl); 36700f792cf9SNaoya Horiguchi goto out_put_page; 3671b4d1d99fSDavid Gibson } 3672106c992aSGerald Schaefer entry = huge_pte_mkdirty(entry); 3673b4d1d99fSDavid Gibson } 3674b4d1d99fSDavid Gibson entry = pte_mkyoung(entry); 3675788c7df4SHugh Dickins if (huge_ptep_set_access_flags(vma, address, ptep, entry, 3676788c7df4SHugh Dickins flags & FAULT_FLAG_WRITE)) 36774b3073e1SRussell King update_mmu_cache(vma, address, ptep); 36780f792cf9SNaoya Horiguchi out_put_page: 36790f792cf9SNaoya Horiguchi if (page != pagecache_page) 36800f792cf9SNaoya Horiguchi unlock_page(page); 36810f792cf9SNaoya Horiguchi put_page(page); 3682cb900f41SKirill A. Shutemov out_ptl: 3683cb900f41SKirill A. Shutemov spin_unlock(ptl); 368457303d80SAndy Whitcroft 368557303d80SAndy Whitcroft if (pagecache_page) { 368657303d80SAndy Whitcroft unlock_page(pagecache_page); 368757303d80SAndy Whitcroft put_page(pagecache_page); 368857303d80SAndy Whitcroft } 3689b4d1d99fSDavid Gibson out_mutex: 3690c672c7f2SMike Kravetz mutex_unlock(&hugetlb_fault_mutex_table[hash]); 36910f792cf9SNaoya Horiguchi /* 36920f792cf9SNaoya Horiguchi * Generally it's safe to hold refcount during waiting page lock. But 36930f792cf9SNaoya Horiguchi * here we just wait to defer the next page fault to avoid busy loop and 36940f792cf9SNaoya Horiguchi * the page is not used after unlocked before returning from the current 36950f792cf9SNaoya Horiguchi * page fault. So we are safe from accessing freed page, even if we wait 36960f792cf9SNaoya Horiguchi * here without taking refcount. 36970f792cf9SNaoya Horiguchi */ 36980f792cf9SNaoya Horiguchi if (need_wait_lock) 36990f792cf9SNaoya Horiguchi wait_on_page_locked(page); 37001e8f889bSDavid Gibson return ret; 370186e5216fSAdam Litke } 370286e5216fSAdam Litke 370328a35716SMichel Lespinasse long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, 370463551ae0SDavid Gibson struct page **pages, struct vm_area_struct **vmas, 370528a35716SMichel Lespinasse unsigned long *position, unsigned long *nr_pages, 370628a35716SMichel Lespinasse long i, unsigned int flags) 370763551ae0SDavid Gibson { 3708d5d4b0aaSChen, Kenneth W unsigned long pfn_offset; 3709d5d4b0aaSChen, Kenneth W unsigned long vaddr = *position; 371028a35716SMichel Lespinasse unsigned long remainder = *nr_pages; 3711a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 371263551ae0SDavid Gibson 371363551ae0SDavid Gibson while (vaddr < vma->vm_end && remainder) { 371463551ae0SDavid Gibson pte_t *pte; 3715cb900f41SKirill A. Shutemov spinlock_t *ptl = NULL; 37162a15efc9SHugh Dickins int absent; 371763551ae0SDavid Gibson struct page *page; 371863551ae0SDavid Gibson 37194c887265SAdam Litke /* 372002057967SDavid Rientjes * If we have a pending SIGKILL, don't keep faulting pages and 372102057967SDavid Rientjes * potentially allocating memory. 372202057967SDavid Rientjes */ 372302057967SDavid Rientjes if (unlikely(fatal_signal_pending(current))) { 372402057967SDavid Rientjes remainder = 0; 372502057967SDavid Rientjes break; 372602057967SDavid Rientjes } 372702057967SDavid Rientjes 372802057967SDavid Rientjes /* 37294c887265SAdam Litke * Some archs (sparc64, sh*) have multiple pte_ts to 37302a15efc9SHugh Dickins * each hugepage. We have to make sure we get the 37314c887265SAdam Litke * first, for the page indexing below to work. 3732cb900f41SKirill A. Shutemov * 3733cb900f41SKirill A. Shutemov * Note that page table lock is not held when pte is null. 37344c887265SAdam Litke */ 3735a5516438SAndi Kleen pte = huge_pte_offset(mm, vaddr & huge_page_mask(h)); 3736cb900f41SKirill A. Shutemov if (pte) 3737cb900f41SKirill A. Shutemov ptl = huge_pte_lock(h, mm, pte); 37382a15efc9SHugh Dickins absent = !pte || huge_pte_none(huge_ptep_get(pte)); 373963551ae0SDavid Gibson 37402a15efc9SHugh Dickins /* 37412a15efc9SHugh Dickins * When coredumping, it suits get_dump_page if we just return 37423ae77f43SHugh Dickins * an error where there's an empty slot with no huge pagecache 37433ae77f43SHugh Dickins * to back it. This way, we avoid allocating a hugepage, and 37443ae77f43SHugh Dickins * the sparse dumpfile avoids allocating disk blocks, but its 37453ae77f43SHugh Dickins * huge holes still show up with zeroes where they need to be. 37462a15efc9SHugh Dickins */ 37473ae77f43SHugh Dickins if (absent && (flags & FOLL_DUMP) && 37483ae77f43SHugh Dickins !hugetlbfs_pagecache_present(h, vma, vaddr)) { 3749cb900f41SKirill A. Shutemov if (pte) 3750cb900f41SKirill A. Shutemov spin_unlock(ptl); 37512a15efc9SHugh Dickins remainder = 0; 37522a15efc9SHugh Dickins break; 37532a15efc9SHugh Dickins } 37542a15efc9SHugh Dickins 37559cc3a5bdSNaoya Horiguchi /* 37569cc3a5bdSNaoya Horiguchi * We need call hugetlb_fault for both hugepages under migration 37579cc3a5bdSNaoya Horiguchi * (in which case hugetlb_fault waits for the migration,) and 37589cc3a5bdSNaoya Horiguchi * hwpoisoned hugepages (in which case we need to prevent the 37599cc3a5bdSNaoya Horiguchi * caller from accessing to them.) In order to do this, we use 37609cc3a5bdSNaoya Horiguchi * here is_swap_pte instead of is_hugetlb_entry_migration and 37619cc3a5bdSNaoya Horiguchi * is_hugetlb_entry_hwpoisoned. This is because it simply covers 37629cc3a5bdSNaoya Horiguchi * both cases, and because we can't follow correct pages 37639cc3a5bdSNaoya Horiguchi * directly from any kind of swap entries. 37649cc3a5bdSNaoya Horiguchi */ 37659cc3a5bdSNaoya Horiguchi if (absent || is_swap_pte(huge_ptep_get(pte)) || 3766106c992aSGerald Schaefer ((flags & FOLL_WRITE) && 3767106c992aSGerald Schaefer !huge_pte_write(huge_ptep_get(pte)))) { 37684c887265SAdam Litke int ret; 37694c887265SAdam Litke 3770cb900f41SKirill A. Shutemov if (pte) 3771cb900f41SKirill A. Shutemov spin_unlock(ptl); 37722a15efc9SHugh Dickins ret = hugetlb_fault(mm, vma, vaddr, 37732a15efc9SHugh Dickins (flags & FOLL_WRITE) ? FAULT_FLAG_WRITE : 0); 3774a89182c7SAdam Litke if (!(ret & VM_FAULT_ERROR)) 37754c887265SAdam Litke continue; 37764c887265SAdam Litke 37771c59827dSHugh Dickins remainder = 0; 37781c59827dSHugh Dickins break; 37791c59827dSHugh Dickins } 378063551ae0SDavid Gibson 3781a5516438SAndi Kleen pfn_offset = (vaddr & ~huge_page_mask(h)) >> PAGE_SHIFT; 37827f2e9525SGerald Schaefer page = pte_page(huge_ptep_get(pte)); 3783d5d4b0aaSChen, Kenneth W same_page: 3784d6692183SChen, Kenneth W if (pages) { 378569d177c2SAndy Whitcroft pages[i] = mem_map_offset(page, pfn_offset); 3786a0368d4eSAndrea Arcangeli get_page_foll(pages[i]); 3787d6692183SChen, Kenneth W } 378863551ae0SDavid Gibson 378963551ae0SDavid Gibson if (vmas) 379063551ae0SDavid Gibson vmas[i] = vma; 379163551ae0SDavid Gibson 379263551ae0SDavid Gibson vaddr += PAGE_SIZE; 3793d5d4b0aaSChen, Kenneth W ++pfn_offset; 379463551ae0SDavid Gibson --remainder; 379563551ae0SDavid Gibson ++i; 3796d5d4b0aaSChen, Kenneth W if (vaddr < vma->vm_end && remainder && 3797a5516438SAndi Kleen pfn_offset < pages_per_huge_page(h)) { 3798d5d4b0aaSChen, Kenneth W /* 3799d5d4b0aaSChen, Kenneth W * We use pfn_offset to avoid touching the pageframes 3800d5d4b0aaSChen, Kenneth W * of this compound page. 3801d5d4b0aaSChen, Kenneth W */ 3802d5d4b0aaSChen, Kenneth W goto same_page; 3803d5d4b0aaSChen, Kenneth W } 3804cb900f41SKirill A. Shutemov spin_unlock(ptl); 380563551ae0SDavid Gibson } 380628a35716SMichel Lespinasse *nr_pages = remainder; 380763551ae0SDavid Gibson *position = vaddr; 380863551ae0SDavid Gibson 38092a15efc9SHugh Dickins return i ? i : -EFAULT; 381063551ae0SDavid Gibson } 38118f860591SZhang, Yanmin 38127da4d641SPeter Zijlstra unsigned long hugetlb_change_protection(struct vm_area_struct *vma, 38138f860591SZhang, Yanmin unsigned long address, unsigned long end, pgprot_t newprot) 38148f860591SZhang, Yanmin { 38158f860591SZhang, Yanmin struct mm_struct *mm = vma->vm_mm; 38168f860591SZhang, Yanmin unsigned long start = address; 38178f860591SZhang, Yanmin pte_t *ptep; 38188f860591SZhang, Yanmin pte_t pte; 3819a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 38207da4d641SPeter Zijlstra unsigned long pages = 0; 38218f860591SZhang, Yanmin 38228f860591SZhang, Yanmin BUG_ON(address >= end); 38238f860591SZhang, Yanmin flush_cache_range(vma, address, end); 38248f860591SZhang, Yanmin 3825a5338093SRik van Riel mmu_notifier_invalidate_range_start(mm, start, end); 382683cde9e8SDavidlohr Bueso i_mmap_lock_write(vma->vm_file->f_mapping); 3827a5516438SAndi Kleen for (; address < end; address += huge_page_size(h)) { 3828cb900f41SKirill A. Shutemov spinlock_t *ptl; 38298f860591SZhang, Yanmin ptep = huge_pte_offset(mm, address); 38308f860591SZhang, Yanmin if (!ptep) 38318f860591SZhang, Yanmin continue; 3832cb900f41SKirill A. Shutemov ptl = huge_pte_lock(h, mm, ptep); 38337da4d641SPeter Zijlstra if (huge_pmd_unshare(mm, &address, ptep)) { 38347da4d641SPeter Zijlstra pages++; 3835cb900f41SKirill A. Shutemov spin_unlock(ptl); 383639dde65cSChen, Kenneth W continue; 38377da4d641SPeter Zijlstra } 3838a8bda28dSNaoya Horiguchi pte = huge_ptep_get(ptep); 3839a8bda28dSNaoya Horiguchi if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { 3840a8bda28dSNaoya Horiguchi spin_unlock(ptl); 3841a8bda28dSNaoya Horiguchi continue; 3842a8bda28dSNaoya Horiguchi } 3843a8bda28dSNaoya Horiguchi if (unlikely(is_hugetlb_entry_migration(pte))) { 3844a8bda28dSNaoya Horiguchi swp_entry_t entry = pte_to_swp_entry(pte); 3845a8bda28dSNaoya Horiguchi 3846a8bda28dSNaoya Horiguchi if (is_write_migration_entry(entry)) { 3847a8bda28dSNaoya Horiguchi pte_t newpte; 3848a8bda28dSNaoya Horiguchi 3849a8bda28dSNaoya Horiguchi make_migration_entry_read(&entry); 3850a8bda28dSNaoya Horiguchi newpte = swp_entry_to_pte(entry); 3851a8bda28dSNaoya Horiguchi set_huge_pte_at(mm, address, ptep, newpte); 3852a8bda28dSNaoya Horiguchi pages++; 3853a8bda28dSNaoya Horiguchi } 3854a8bda28dSNaoya Horiguchi spin_unlock(ptl); 3855a8bda28dSNaoya Horiguchi continue; 3856a8bda28dSNaoya Horiguchi } 3857a8bda28dSNaoya Horiguchi if (!huge_pte_none(pte)) { 38588f860591SZhang, Yanmin pte = huge_ptep_get_and_clear(mm, address, ptep); 3859106c992aSGerald Schaefer pte = pte_mkhuge(huge_pte_modify(pte, newprot)); 3860be7517d6STony Lu pte = arch_make_huge_pte(pte, vma, NULL, 0); 38618f860591SZhang, Yanmin set_huge_pte_at(mm, address, ptep, pte); 38627da4d641SPeter Zijlstra pages++; 38638f860591SZhang, Yanmin } 3864cb900f41SKirill A. Shutemov spin_unlock(ptl); 38658f860591SZhang, Yanmin } 3866d833352aSMel Gorman /* 3867c8c06efaSDavidlohr Bueso * Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare 3868d833352aSMel Gorman * may have cleared our pud entry and done put_page on the page table: 3869c8c06efaSDavidlohr Bueso * once we release i_mmap_rwsem, another task can do the final put_page 3870d833352aSMel Gorman * and that page table be reused and filled with junk. 3871d833352aSMel Gorman */ 38728f860591SZhang, Yanmin flush_tlb_range(vma, start, end); 387334ee645eSJoerg Roedel mmu_notifier_invalidate_range(mm, start, end); 387483cde9e8SDavidlohr Bueso i_mmap_unlock_write(vma->vm_file->f_mapping); 3875a5338093SRik van Riel mmu_notifier_invalidate_range_end(mm, start, end); 38767da4d641SPeter Zijlstra 38777da4d641SPeter Zijlstra return pages << h->order; 38788f860591SZhang, Yanmin } 38798f860591SZhang, Yanmin 3880a1e78772SMel Gorman int hugetlb_reserve_pages(struct inode *inode, 3881a1e78772SMel Gorman long from, long to, 38825a6fe125SMel Gorman struct vm_area_struct *vma, 3883ca16d140SKOSAKI Motohiro vm_flags_t vm_flags) 3884e4e574b7SAdam Litke { 388517c9d12eSMel Gorman long ret, chg; 3886a5516438SAndi Kleen struct hstate *h = hstate_inode(inode); 388790481622SDavid Gibson struct hugepage_subpool *spool = subpool_inode(inode); 38889119a41eSJoonsoo Kim struct resv_map *resv_map; 38891c5ecae3SMike Kravetz long gbl_reserve; 3890e4e574b7SAdam Litke 3891a1e78772SMel Gorman /* 389217c9d12eSMel Gorman * Only apply hugepage reservation if asked. At fault time, an 389317c9d12eSMel Gorman * attempt will be made for VM_NORESERVE to allocate a page 389490481622SDavid Gibson * without using reserves 389517c9d12eSMel Gorman */ 3896ca16d140SKOSAKI Motohiro if (vm_flags & VM_NORESERVE) 389717c9d12eSMel Gorman return 0; 389817c9d12eSMel Gorman 389917c9d12eSMel Gorman /* 3900a1e78772SMel Gorman * Shared mappings base their reservation on the number of pages that 3901a1e78772SMel Gorman * are already allocated on behalf of the file. Private mappings need 3902a1e78772SMel Gorman * to reserve the full area even if read-only as mprotect() may be 3903a1e78772SMel Gorman * called to make the mapping read-write. Assume !vma is a shm mapping 3904a1e78772SMel Gorman */ 39059119a41eSJoonsoo Kim if (!vma || vma->vm_flags & VM_MAYSHARE) { 39064e35f483SJoonsoo Kim resv_map = inode_resv_map(inode); 39079119a41eSJoonsoo Kim 39081406ec9bSJoonsoo Kim chg = region_chg(resv_map, from, to); 39099119a41eSJoonsoo Kim 39109119a41eSJoonsoo Kim } else { 39119119a41eSJoonsoo Kim resv_map = resv_map_alloc(); 39125a6fe125SMel Gorman if (!resv_map) 39135a6fe125SMel Gorman return -ENOMEM; 39145a6fe125SMel Gorman 391517c9d12eSMel Gorman chg = to - from; 391617c9d12eSMel Gorman 39175a6fe125SMel Gorman set_vma_resv_map(vma, resv_map); 39185a6fe125SMel Gorman set_vma_resv_flags(vma, HPAGE_RESV_OWNER); 39195a6fe125SMel Gorman } 39205a6fe125SMel Gorman 3921c50ac050SDave Hansen if (chg < 0) { 3922c50ac050SDave Hansen ret = chg; 3923c50ac050SDave Hansen goto out_err; 3924c50ac050SDave Hansen } 392517c9d12eSMel Gorman 39261c5ecae3SMike Kravetz /* 39271c5ecae3SMike Kravetz * There must be enough pages in the subpool for the mapping. If 39281c5ecae3SMike Kravetz * the subpool has a minimum size, there may be some global 39291c5ecae3SMike Kravetz * reservations already in place (gbl_reserve). 39301c5ecae3SMike Kravetz */ 39311c5ecae3SMike Kravetz gbl_reserve = hugepage_subpool_get_pages(spool, chg); 39321c5ecae3SMike Kravetz if (gbl_reserve < 0) { 3933c50ac050SDave Hansen ret = -ENOSPC; 3934c50ac050SDave Hansen goto out_err; 3935c50ac050SDave Hansen } 393617c9d12eSMel Gorman 393717c9d12eSMel Gorman /* 393817c9d12eSMel Gorman * Check enough hugepages are available for the reservation. 393990481622SDavid Gibson * Hand the pages back to the subpool if there are not 394017c9d12eSMel Gorman */ 39411c5ecae3SMike Kravetz ret = hugetlb_acct_memory(h, gbl_reserve); 394217c9d12eSMel Gorman if (ret < 0) { 39431c5ecae3SMike Kravetz /* put back original number of pages, chg */ 39441c5ecae3SMike Kravetz (void)hugepage_subpool_put_pages(spool, chg); 3945c50ac050SDave Hansen goto out_err; 394617c9d12eSMel Gorman } 394717c9d12eSMel Gorman 394817c9d12eSMel Gorman /* 394917c9d12eSMel Gorman * Account for the reservations made. Shared mappings record regions 395017c9d12eSMel Gorman * that have reservations as they are shared by multiple VMAs. 395117c9d12eSMel Gorman * When the last VMA disappears, the region map says how much 395217c9d12eSMel Gorman * the reservation was and the page cache tells how much of 395317c9d12eSMel Gorman * the reservation was consumed. Private mappings are per-VMA and 395417c9d12eSMel Gorman * only the consumed reservations are tracked. When the VMA 395517c9d12eSMel Gorman * disappears, the original reservation is the VMA size and the 395617c9d12eSMel Gorman * consumed reservations are stored in the map. Hence, nothing 395717c9d12eSMel Gorman * else has to be done for private mappings here 395817c9d12eSMel Gorman */ 395933039678SMike Kravetz if (!vma || vma->vm_flags & VM_MAYSHARE) { 396033039678SMike Kravetz long add = region_add(resv_map, from, to); 396133039678SMike Kravetz 396233039678SMike Kravetz if (unlikely(chg > add)) { 396333039678SMike Kravetz /* 396433039678SMike Kravetz * pages in this range were added to the reserve 396533039678SMike Kravetz * map between region_chg and region_add. This 396633039678SMike Kravetz * indicates a race with alloc_huge_page. Adjust 396733039678SMike Kravetz * the subpool and reserve counts modified above 396833039678SMike Kravetz * based on the difference. 396933039678SMike Kravetz */ 397033039678SMike Kravetz long rsv_adjust; 397133039678SMike Kravetz 397233039678SMike Kravetz rsv_adjust = hugepage_subpool_put_pages(spool, 397333039678SMike Kravetz chg - add); 397433039678SMike Kravetz hugetlb_acct_memory(h, -rsv_adjust); 397533039678SMike Kravetz } 397633039678SMike Kravetz } 3977a43a8c39SChen, Kenneth W return 0; 3978c50ac050SDave Hansen out_err: 39795e911373SMike Kravetz if (!vma || vma->vm_flags & VM_MAYSHARE) 39805e911373SMike Kravetz region_abort(resv_map, from, to); 3981f031dd27SJoonsoo Kim if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) 3982f031dd27SJoonsoo Kim kref_put(&resv_map->refs, resv_map_release); 3983c50ac050SDave Hansen return ret; 3984a43a8c39SChen, Kenneth W } 3985a43a8c39SChen, Kenneth W 3986b5cec28dSMike Kravetz long hugetlb_unreserve_pages(struct inode *inode, long start, long end, 3987b5cec28dSMike Kravetz long freed) 3988a43a8c39SChen, Kenneth W { 3989a5516438SAndi Kleen struct hstate *h = hstate_inode(inode); 39904e35f483SJoonsoo Kim struct resv_map *resv_map = inode_resv_map(inode); 39919119a41eSJoonsoo Kim long chg = 0; 399290481622SDavid Gibson struct hugepage_subpool *spool = subpool_inode(inode); 39931c5ecae3SMike Kravetz long gbl_reserve; 399445c682a6SKen Chen 3995b5cec28dSMike Kravetz if (resv_map) { 3996b5cec28dSMike Kravetz chg = region_del(resv_map, start, end); 3997b5cec28dSMike Kravetz /* 3998b5cec28dSMike Kravetz * region_del() can fail in the rare case where a region 3999b5cec28dSMike Kravetz * must be split and another region descriptor can not be 4000b5cec28dSMike Kravetz * allocated. If end == LONG_MAX, it will not fail. 4001b5cec28dSMike Kravetz */ 4002b5cec28dSMike Kravetz if (chg < 0) 4003b5cec28dSMike Kravetz return chg; 4004b5cec28dSMike Kravetz } 4005b5cec28dSMike Kravetz 400645c682a6SKen Chen spin_lock(&inode->i_lock); 4007e4c6f8beSEric Sandeen inode->i_blocks -= (blocks_per_huge_page(h) * freed); 400845c682a6SKen Chen spin_unlock(&inode->i_lock); 400945c682a6SKen Chen 40101c5ecae3SMike Kravetz /* 40111c5ecae3SMike Kravetz * If the subpool has a minimum size, the number of global 40121c5ecae3SMike Kravetz * reservations to be released may be adjusted. 40131c5ecae3SMike Kravetz */ 40141c5ecae3SMike Kravetz gbl_reserve = hugepage_subpool_put_pages(spool, (chg - freed)); 40151c5ecae3SMike Kravetz hugetlb_acct_memory(h, -gbl_reserve); 4016b5cec28dSMike Kravetz 4017b5cec28dSMike Kravetz return 0; 4018a43a8c39SChen, Kenneth W } 401993f70f90SNaoya Horiguchi 40203212b535SSteve Capper #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE 40213212b535SSteve Capper static unsigned long page_table_shareable(struct vm_area_struct *svma, 40223212b535SSteve Capper struct vm_area_struct *vma, 40233212b535SSteve Capper unsigned long addr, pgoff_t idx) 40243212b535SSteve Capper { 40253212b535SSteve Capper unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) + 40263212b535SSteve Capper svma->vm_start; 40273212b535SSteve Capper unsigned long sbase = saddr & PUD_MASK; 40283212b535SSteve Capper unsigned long s_end = sbase + PUD_SIZE; 40293212b535SSteve Capper 40303212b535SSteve Capper /* Allow segments to share if only one is marked locked */ 40313212b535SSteve Capper unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED; 40323212b535SSteve Capper unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED; 40333212b535SSteve Capper 40343212b535SSteve Capper /* 40353212b535SSteve Capper * match the virtual addresses, permission and the alignment of the 40363212b535SSteve Capper * page table page. 40373212b535SSteve Capper */ 40383212b535SSteve Capper if (pmd_index(addr) != pmd_index(saddr) || 40393212b535SSteve Capper vm_flags != svm_flags || 40403212b535SSteve Capper sbase < svma->vm_start || svma->vm_end < s_end) 40413212b535SSteve Capper return 0; 40423212b535SSteve Capper 40433212b535SSteve Capper return saddr; 40443212b535SSteve Capper } 40453212b535SSteve Capper 404631aafb45SNicholas Krause static bool vma_shareable(struct vm_area_struct *vma, unsigned long addr) 40473212b535SSteve Capper { 40483212b535SSteve Capper unsigned long base = addr & PUD_MASK; 40493212b535SSteve Capper unsigned long end = base + PUD_SIZE; 40503212b535SSteve Capper 40513212b535SSteve Capper /* 40523212b535SSteve Capper * check on proper vm_flags and page table alignment 40533212b535SSteve Capper */ 40543212b535SSteve Capper if (vma->vm_flags & VM_MAYSHARE && 40553212b535SSteve Capper vma->vm_start <= base && end <= vma->vm_end) 405631aafb45SNicholas Krause return true; 405731aafb45SNicholas Krause return false; 40583212b535SSteve Capper } 40593212b535SSteve Capper 40603212b535SSteve Capper /* 40613212b535SSteve Capper * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() 40623212b535SSteve Capper * and returns the corresponding pte. While this is not necessary for the 40633212b535SSteve Capper * !shared pmd case because we can allocate the pmd later as well, it makes the 40643212b535SSteve Capper * code much cleaner. pmd allocation is essential for the shared case because 4065c8c06efaSDavidlohr Bueso * pud has to be populated inside the same i_mmap_rwsem section - otherwise 40663212b535SSteve Capper * racing tasks could either miss the sharing (see huge_pte_offset) or select a 40673212b535SSteve Capper * bad pmd for sharing. 40683212b535SSteve Capper */ 40693212b535SSteve Capper pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) 40703212b535SSteve Capper { 40713212b535SSteve Capper struct vm_area_struct *vma = find_vma(mm, addr); 40723212b535SSteve Capper struct address_space *mapping = vma->vm_file->f_mapping; 40733212b535SSteve Capper pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + 40743212b535SSteve Capper vma->vm_pgoff; 40753212b535SSteve Capper struct vm_area_struct *svma; 40763212b535SSteve Capper unsigned long saddr; 40773212b535SSteve Capper pte_t *spte = NULL; 40783212b535SSteve Capper pte_t *pte; 4079cb900f41SKirill A. Shutemov spinlock_t *ptl; 40803212b535SSteve Capper 40813212b535SSteve Capper if (!vma_shareable(vma, addr)) 40823212b535SSteve Capper return (pte_t *)pmd_alloc(mm, pud, addr); 40833212b535SSteve Capper 408483cde9e8SDavidlohr Bueso i_mmap_lock_write(mapping); 40853212b535SSteve Capper vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { 40863212b535SSteve Capper if (svma == vma) 40873212b535SSteve Capper continue; 40883212b535SSteve Capper 40893212b535SSteve Capper saddr = page_table_shareable(svma, vma, addr, idx); 40903212b535SSteve Capper if (saddr) { 40913212b535SSteve Capper spte = huge_pte_offset(svma->vm_mm, saddr); 40923212b535SSteve Capper if (spte) { 4093dc6c9a35SKirill A. Shutemov mm_inc_nr_pmds(mm); 40943212b535SSteve Capper get_page(virt_to_page(spte)); 40953212b535SSteve Capper break; 40963212b535SSteve Capper } 40973212b535SSteve Capper } 40983212b535SSteve Capper } 40993212b535SSteve Capper 41003212b535SSteve Capper if (!spte) 41013212b535SSteve Capper goto out; 41023212b535SSteve Capper 4103cb900f41SKirill A. Shutemov ptl = huge_pte_lockptr(hstate_vma(vma), mm, spte); 4104cb900f41SKirill A. Shutemov spin_lock(ptl); 4105dc6c9a35SKirill A. Shutemov if (pud_none(*pud)) { 41063212b535SSteve Capper pud_populate(mm, pud, 41073212b535SSteve Capper (pmd_t *)((unsigned long)spte & PAGE_MASK)); 4108dc6c9a35SKirill A. Shutemov } else { 41093212b535SSteve Capper put_page(virt_to_page(spte)); 4110dc6c9a35SKirill A. Shutemov mm_inc_nr_pmds(mm); 4111dc6c9a35SKirill A. Shutemov } 4112cb900f41SKirill A. Shutemov spin_unlock(ptl); 41133212b535SSteve Capper out: 41143212b535SSteve Capper pte = (pte_t *)pmd_alloc(mm, pud, addr); 411583cde9e8SDavidlohr Bueso i_mmap_unlock_write(mapping); 41163212b535SSteve Capper return pte; 41173212b535SSteve Capper } 41183212b535SSteve Capper 41193212b535SSteve Capper /* 41203212b535SSteve Capper * unmap huge page backed by shared pte. 41213212b535SSteve Capper * 41223212b535SSteve Capper * Hugetlb pte page is ref counted at the time of mapping. If pte is shared 41233212b535SSteve Capper * indicated by page_count > 1, unmap is achieved by clearing pud and 41243212b535SSteve Capper * decrementing the ref count. If count == 1, the pte page is not shared. 41253212b535SSteve Capper * 4126cb900f41SKirill A. Shutemov * called with page table lock held. 41273212b535SSteve Capper * 41283212b535SSteve Capper * returns: 1 successfully unmapped a shared pte page 41293212b535SSteve Capper * 0 the underlying pte page is not shared, or it is the last user 41303212b535SSteve Capper */ 41313212b535SSteve Capper int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) 41323212b535SSteve Capper { 41333212b535SSteve Capper pgd_t *pgd = pgd_offset(mm, *addr); 41343212b535SSteve Capper pud_t *pud = pud_offset(pgd, *addr); 41353212b535SSteve Capper 41363212b535SSteve Capper BUG_ON(page_count(virt_to_page(ptep)) == 0); 41373212b535SSteve Capper if (page_count(virt_to_page(ptep)) == 1) 41383212b535SSteve Capper return 0; 41393212b535SSteve Capper 41403212b535SSteve Capper pud_clear(pud); 41413212b535SSteve Capper put_page(virt_to_page(ptep)); 4142dc6c9a35SKirill A. Shutemov mm_dec_nr_pmds(mm); 41433212b535SSteve Capper *addr = ALIGN(*addr, HPAGE_SIZE * PTRS_PER_PTE) - HPAGE_SIZE; 41443212b535SSteve Capper return 1; 41453212b535SSteve Capper } 41469e5fc74cSSteve Capper #define want_pmd_share() (1) 41479e5fc74cSSteve Capper #else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ 41489e5fc74cSSteve Capper pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) 41499e5fc74cSSteve Capper { 41509e5fc74cSSteve Capper return NULL; 41519e5fc74cSSteve Capper } 4152e81f2d22SZhang Zhen 4153e81f2d22SZhang Zhen int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) 4154e81f2d22SZhang Zhen { 4155e81f2d22SZhang Zhen return 0; 4156e81f2d22SZhang Zhen } 41579e5fc74cSSteve Capper #define want_pmd_share() (0) 41583212b535SSteve Capper #endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ 41593212b535SSteve Capper 41609e5fc74cSSteve Capper #ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB 41619e5fc74cSSteve Capper pte_t *huge_pte_alloc(struct mm_struct *mm, 41629e5fc74cSSteve Capper unsigned long addr, unsigned long sz) 41639e5fc74cSSteve Capper { 41649e5fc74cSSteve Capper pgd_t *pgd; 41659e5fc74cSSteve Capper pud_t *pud; 41669e5fc74cSSteve Capper pte_t *pte = NULL; 41679e5fc74cSSteve Capper 41689e5fc74cSSteve Capper pgd = pgd_offset(mm, addr); 41699e5fc74cSSteve Capper pud = pud_alloc(mm, pgd, addr); 41709e5fc74cSSteve Capper if (pud) { 41719e5fc74cSSteve Capper if (sz == PUD_SIZE) { 41729e5fc74cSSteve Capper pte = (pte_t *)pud; 41739e5fc74cSSteve Capper } else { 41749e5fc74cSSteve Capper BUG_ON(sz != PMD_SIZE); 41759e5fc74cSSteve Capper if (want_pmd_share() && pud_none(*pud)) 41769e5fc74cSSteve Capper pte = huge_pmd_share(mm, addr, pud); 41779e5fc74cSSteve Capper else 41789e5fc74cSSteve Capper pte = (pte_t *)pmd_alloc(mm, pud, addr); 41799e5fc74cSSteve Capper } 41809e5fc74cSSteve Capper } 41819e5fc74cSSteve Capper BUG_ON(pte && !pte_none(*pte) && !pte_huge(*pte)); 41829e5fc74cSSteve Capper 41839e5fc74cSSteve Capper return pte; 41849e5fc74cSSteve Capper } 41859e5fc74cSSteve Capper 41869e5fc74cSSteve Capper pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) 41879e5fc74cSSteve Capper { 41889e5fc74cSSteve Capper pgd_t *pgd; 41899e5fc74cSSteve Capper pud_t *pud; 41909e5fc74cSSteve Capper pmd_t *pmd = NULL; 41919e5fc74cSSteve Capper 41929e5fc74cSSteve Capper pgd = pgd_offset(mm, addr); 41939e5fc74cSSteve Capper if (pgd_present(*pgd)) { 41949e5fc74cSSteve Capper pud = pud_offset(pgd, addr); 41959e5fc74cSSteve Capper if (pud_present(*pud)) { 41969e5fc74cSSteve Capper if (pud_huge(*pud)) 41979e5fc74cSSteve Capper return (pte_t *)pud; 41989e5fc74cSSteve Capper pmd = pmd_offset(pud, addr); 41999e5fc74cSSteve Capper } 42009e5fc74cSSteve Capper } 42019e5fc74cSSteve Capper return (pte_t *) pmd; 42029e5fc74cSSteve Capper } 42039e5fc74cSSteve Capper 420461f77edaSNaoya Horiguchi #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ 420561f77edaSNaoya Horiguchi 420661f77edaSNaoya Horiguchi /* 420761f77edaSNaoya Horiguchi * These functions are overwritable if your architecture needs its own 420861f77edaSNaoya Horiguchi * behavior. 420961f77edaSNaoya Horiguchi */ 421061f77edaSNaoya Horiguchi struct page * __weak 421161f77edaSNaoya Horiguchi follow_huge_addr(struct mm_struct *mm, unsigned long address, 421261f77edaSNaoya Horiguchi int write) 421361f77edaSNaoya Horiguchi { 421461f77edaSNaoya Horiguchi return ERR_PTR(-EINVAL); 421561f77edaSNaoya Horiguchi } 421661f77edaSNaoya Horiguchi 421761f77edaSNaoya Horiguchi struct page * __weak 42189e5fc74cSSteve Capper follow_huge_pmd(struct mm_struct *mm, unsigned long address, 4219e66f17ffSNaoya Horiguchi pmd_t *pmd, int flags) 42209e5fc74cSSteve Capper { 4221e66f17ffSNaoya Horiguchi struct page *page = NULL; 4222e66f17ffSNaoya Horiguchi spinlock_t *ptl; 4223e66f17ffSNaoya Horiguchi retry: 4224e66f17ffSNaoya Horiguchi ptl = pmd_lockptr(mm, pmd); 4225e66f17ffSNaoya Horiguchi spin_lock(ptl); 4226e66f17ffSNaoya Horiguchi /* 4227e66f17ffSNaoya Horiguchi * make sure that the address range covered by this pmd is not 4228e66f17ffSNaoya Horiguchi * unmapped from other threads. 4229e66f17ffSNaoya Horiguchi */ 4230e66f17ffSNaoya Horiguchi if (!pmd_huge(*pmd)) 4231e66f17ffSNaoya Horiguchi goto out; 4232e66f17ffSNaoya Horiguchi if (pmd_present(*pmd)) { 423397534127SGerald Schaefer page = pmd_page(*pmd) + ((address & ~PMD_MASK) >> PAGE_SHIFT); 4234e66f17ffSNaoya Horiguchi if (flags & FOLL_GET) 4235e66f17ffSNaoya Horiguchi get_page(page); 4236e66f17ffSNaoya Horiguchi } else { 4237e66f17ffSNaoya Horiguchi if (is_hugetlb_entry_migration(huge_ptep_get((pte_t *)pmd))) { 4238e66f17ffSNaoya Horiguchi spin_unlock(ptl); 4239e66f17ffSNaoya Horiguchi __migration_entry_wait(mm, (pte_t *)pmd, ptl); 4240e66f17ffSNaoya Horiguchi goto retry; 4241e66f17ffSNaoya Horiguchi } 4242e66f17ffSNaoya Horiguchi /* 4243e66f17ffSNaoya Horiguchi * hwpoisoned entry is treated as no_page_table in 4244e66f17ffSNaoya Horiguchi * follow_page_mask(). 4245e66f17ffSNaoya Horiguchi */ 4246e66f17ffSNaoya Horiguchi } 4247e66f17ffSNaoya Horiguchi out: 4248e66f17ffSNaoya Horiguchi spin_unlock(ptl); 42499e5fc74cSSteve Capper return page; 42509e5fc74cSSteve Capper } 42519e5fc74cSSteve Capper 425261f77edaSNaoya Horiguchi struct page * __weak 42539e5fc74cSSteve Capper follow_huge_pud(struct mm_struct *mm, unsigned long address, 4254e66f17ffSNaoya Horiguchi pud_t *pud, int flags) 42559e5fc74cSSteve Capper { 4256e66f17ffSNaoya Horiguchi if (flags & FOLL_GET) 4257e66f17ffSNaoya Horiguchi return NULL; 42589e5fc74cSSteve Capper 4259e66f17ffSNaoya Horiguchi return pte_page(*(pte_t *)pud) + ((address & ~PUD_MASK) >> PAGE_SHIFT); 42609e5fc74cSSteve Capper } 42619e5fc74cSSteve Capper 4262d5bd9106SAndi Kleen #ifdef CONFIG_MEMORY_FAILURE 4263d5bd9106SAndi Kleen 426493f70f90SNaoya Horiguchi /* 426593f70f90SNaoya Horiguchi * This function is called from memory failure code. 426693f70f90SNaoya Horiguchi * Assume the caller holds page lock of the head page. 426793f70f90SNaoya Horiguchi */ 42686de2b1aaSNaoya Horiguchi int dequeue_hwpoisoned_huge_page(struct page *hpage) 426993f70f90SNaoya Horiguchi { 427093f70f90SNaoya Horiguchi struct hstate *h = page_hstate(hpage); 427193f70f90SNaoya Horiguchi int nid = page_to_nid(hpage); 42726de2b1aaSNaoya Horiguchi int ret = -EBUSY; 427393f70f90SNaoya Horiguchi 427493f70f90SNaoya Horiguchi spin_lock(&hugetlb_lock); 42757e1f049eSNaoya Horiguchi /* 42767e1f049eSNaoya Horiguchi * Just checking !page_huge_active is not enough, because that could be 42777e1f049eSNaoya Horiguchi * an isolated/hwpoisoned hugepage (which have >0 refcount). 42787e1f049eSNaoya Horiguchi */ 42797e1f049eSNaoya Horiguchi if (!page_huge_active(hpage) && !page_count(hpage)) { 428056f2fb14SNaoya Horiguchi /* 428156f2fb14SNaoya Horiguchi * Hwpoisoned hugepage isn't linked to activelist or freelist, 428256f2fb14SNaoya Horiguchi * but dangling hpage->lru can trigger list-debug warnings 428356f2fb14SNaoya Horiguchi * (this happens when we call unpoison_memory() on it), 428456f2fb14SNaoya Horiguchi * so let it point to itself with list_del_init(). 428556f2fb14SNaoya Horiguchi */ 428656f2fb14SNaoya Horiguchi list_del_init(&hpage->lru); 42878c6c2ecbSNaoya Horiguchi set_page_refcounted(hpage); 428893f70f90SNaoya Horiguchi h->free_huge_pages--; 428993f70f90SNaoya Horiguchi h->free_huge_pages_node[nid]--; 42906de2b1aaSNaoya Horiguchi ret = 0; 429193f70f90SNaoya Horiguchi } 42926de2b1aaSNaoya Horiguchi spin_unlock(&hugetlb_lock); 42936de2b1aaSNaoya Horiguchi return ret; 42946de2b1aaSNaoya Horiguchi } 42956de2b1aaSNaoya Horiguchi #endif 429631caf665SNaoya Horiguchi 429731caf665SNaoya Horiguchi bool isolate_huge_page(struct page *page, struct list_head *list) 429831caf665SNaoya Horiguchi { 4299bcc54222SNaoya Horiguchi bool ret = true; 4300bcc54222SNaoya Horiguchi 4301309381feSSasha Levin VM_BUG_ON_PAGE(!PageHead(page), page); 430231caf665SNaoya Horiguchi spin_lock(&hugetlb_lock); 4303bcc54222SNaoya Horiguchi if (!page_huge_active(page) || !get_page_unless_zero(page)) { 4304bcc54222SNaoya Horiguchi ret = false; 4305bcc54222SNaoya Horiguchi goto unlock; 4306bcc54222SNaoya Horiguchi } 4307bcc54222SNaoya Horiguchi clear_page_huge_active(page); 430831caf665SNaoya Horiguchi list_move_tail(&page->lru, list); 4309bcc54222SNaoya Horiguchi unlock: 431031caf665SNaoya Horiguchi spin_unlock(&hugetlb_lock); 4311bcc54222SNaoya Horiguchi return ret; 431231caf665SNaoya Horiguchi } 431331caf665SNaoya Horiguchi 431431caf665SNaoya Horiguchi void putback_active_hugepage(struct page *page) 431531caf665SNaoya Horiguchi { 4316309381feSSasha Levin VM_BUG_ON_PAGE(!PageHead(page), page); 431731caf665SNaoya Horiguchi spin_lock(&hugetlb_lock); 4318bcc54222SNaoya Horiguchi set_page_huge_active(page); 431931caf665SNaoya Horiguchi list_move_tail(&page->lru, &(page_hstate(page))->hugepage_activelist); 432031caf665SNaoya Horiguchi spin_unlock(&hugetlb_lock); 432131caf665SNaoya Horiguchi put_page(page); 432231caf665SNaoya Horiguchi } 4323