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/mm.h> 8e1759c21SAlexey Dobriyan #include <linux/seq_file.h> 91da177e4SLinus Torvalds #include <linux/sysctl.h> 101da177e4SLinus Torvalds #include <linux/highmem.h> 11cddb8a5cSAndrea Arcangeli #include <linux/mmu_notifier.h> 121da177e4SLinus Torvalds #include <linux/nodemask.h> 1363551ae0SDavid Gibson #include <linux/pagemap.h> 145da7ca86SChristoph Lameter #include <linux/mempolicy.h> 153b32123dSGideon Israel Dsouza #include <linux/compiler.h> 16aea47ff3SChristoph Lameter #include <linux/cpuset.h> 173935baa9SDavid Gibson #include <linux/mutex.h> 18aa888a74SAndi Kleen #include <linux/bootmem.h> 19a3437870SNishanth Aravamudan #include <linux/sysfs.h> 205a0e3ad6STejun Heo #include <linux/slab.h> 210fe6e20bSNaoya Horiguchi #include <linux/rmap.h> 22fd6a03edSNaoya Horiguchi #include <linux/swap.h> 23fd6a03edSNaoya Horiguchi #include <linux/swapops.h> 24c8721bbbSNaoya Horiguchi #include <linux/page-isolation.h> 258382d914SDavidlohr Bueso #include <linux/jhash.h> 26d6606683SLinus Torvalds 2763551ae0SDavid Gibson #include <asm/page.h> 2863551ae0SDavid Gibson #include <asm/pgtable.h> 2924669e58SAneesh Kumar K.V #include <asm/tlb.h> 3063551ae0SDavid Gibson 3124669e58SAneesh Kumar K.V #include <linux/io.h> 3263551ae0SDavid Gibson #include <linux/hugetlb.h> 339dd540e2SAneesh Kumar K.V #include <linux/hugetlb_cgroup.h> 349a305230SLee Schermerhorn #include <linux/node.h> 357835e98bSNick Piggin #include "internal.h" 361da177e4SLinus Torvalds 37753162cdSAndrey Ryabinin int hugepages_treat_as_movable; 38a5516438SAndi Kleen 39c3f38a38SAneesh Kumar K.V int hugetlb_max_hstate __read_mostly; 40e5ff2159SAndi Kleen unsigned int default_hstate_idx; 41e5ff2159SAndi Kleen struct hstate hstates[HUGE_MAX_HSTATE]; 42641844f5SNaoya Horiguchi /* 43641844f5SNaoya Horiguchi * Minimum page order among possible hugepage sizes, set to a proper value 44641844f5SNaoya Horiguchi * at boot time. 45641844f5SNaoya Horiguchi */ 46641844f5SNaoya Horiguchi static unsigned int minimum_order __read_mostly = UINT_MAX; 47e5ff2159SAndi Kleen 4853ba51d2SJon Tollefson __initdata LIST_HEAD(huge_boot_pages); 4953ba51d2SJon Tollefson 50e5ff2159SAndi Kleen /* for command line parsing */ 51e5ff2159SAndi Kleen static struct hstate * __initdata parsed_hstate; 52e5ff2159SAndi Kleen static unsigned long __initdata default_hstate_max_huge_pages; 53e11bfbfcSNick Piggin static unsigned long __initdata default_hstate_size; 549fee021dSVaishali Thakkar static bool __initdata parsed_valid_hugepagesz = true; 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 14809a95e29SMike Kravetz /* minimum size accounting */ 14909a95e29SMike Kravetz if (spool->min_hpages != -1 && spool->rsv_hpages) { 1501c5ecae3SMike Kravetz if (delta > spool->rsv_hpages) { 1511c5ecae3SMike Kravetz /* 1521c5ecae3SMike Kravetz * Asking for more reserves than those already taken on 1531c5ecae3SMike Kravetz * behalf of subpool. Return difference. 1541c5ecae3SMike Kravetz */ 1551c5ecae3SMike Kravetz ret = delta - spool->rsv_hpages; 1561c5ecae3SMike Kravetz spool->rsv_hpages = 0; 1571c5ecae3SMike Kravetz } else { 1581c5ecae3SMike Kravetz ret = 0; /* reserves already accounted for */ 1591c5ecae3SMike Kravetz spool->rsv_hpages -= delta; 1601c5ecae3SMike Kravetz } 1611c5ecae3SMike Kravetz } 1621c5ecae3SMike Kravetz 1631c5ecae3SMike Kravetz unlock_ret: 1641c5ecae3SMike Kravetz spin_unlock(&spool->lock); 16590481622SDavid Gibson return ret; 16690481622SDavid Gibson } 16790481622SDavid Gibson 1681c5ecae3SMike Kravetz /* 1691c5ecae3SMike Kravetz * Subpool accounting for freeing and unreserving pages. 1701c5ecae3SMike Kravetz * Return the number of global page reservations that must be dropped. 1711c5ecae3SMike Kravetz * The return value may only be different than the passed value (delta) 1721c5ecae3SMike Kravetz * in the case where a subpool minimum size must be maintained. 1731c5ecae3SMike Kravetz */ 1741c5ecae3SMike Kravetz static long hugepage_subpool_put_pages(struct hugepage_subpool *spool, 17590481622SDavid Gibson long delta) 17690481622SDavid Gibson { 1771c5ecae3SMike Kravetz long ret = delta; 1781c5ecae3SMike Kravetz 17990481622SDavid Gibson if (!spool) 1801c5ecae3SMike Kravetz return delta; 18190481622SDavid Gibson 18290481622SDavid Gibson spin_lock(&spool->lock); 1831c5ecae3SMike Kravetz 1841c5ecae3SMike Kravetz if (spool->max_hpages != -1) /* maximum size accounting */ 18590481622SDavid Gibson spool->used_hpages -= delta; 1861c5ecae3SMike Kravetz 18709a95e29SMike Kravetz /* minimum size accounting */ 18809a95e29SMike Kravetz if (spool->min_hpages != -1 && spool->used_hpages < spool->min_hpages) { 1891c5ecae3SMike Kravetz if (spool->rsv_hpages + delta <= spool->min_hpages) 1901c5ecae3SMike Kravetz ret = 0; 1911c5ecae3SMike Kravetz else 1921c5ecae3SMike Kravetz ret = spool->rsv_hpages + delta - spool->min_hpages; 1931c5ecae3SMike Kravetz 1941c5ecae3SMike Kravetz spool->rsv_hpages += delta; 1951c5ecae3SMike Kravetz if (spool->rsv_hpages > spool->min_hpages) 1961c5ecae3SMike Kravetz spool->rsv_hpages = spool->min_hpages; 1971c5ecae3SMike Kravetz } 1981c5ecae3SMike Kravetz 1991c5ecae3SMike Kravetz /* 2001c5ecae3SMike Kravetz * If hugetlbfs_put_super couldn't free spool due to an outstanding 2011c5ecae3SMike Kravetz * quota reference, free it now. 2021c5ecae3SMike Kravetz */ 20390481622SDavid Gibson unlock_or_release_subpool(spool); 2041c5ecae3SMike Kravetz 2051c5ecae3SMike Kravetz return ret; 20690481622SDavid Gibson } 20790481622SDavid Gibson 20890481622SDavid Gibson static inline struct hugepage_subpool *subpool_inode(struct inode *inode) 20990481622SDavid Gibson { 21090481622SDavid Gibson return HUGETLBFS_SB(inode->i_sb)->spool; 21190481622SDavid Gibson } 21290481622SDavid Gibson 21390481622SDavid Gibson static inline struct hugepage_subpool *subpool_vma(struct vm_area_struct *vma) 21490481622SDavid Gibson { 215496ad9aaSAl Viro return subpool_inode(file_inode(vma->vm_file)); 21690481622SDavid Gibson } 21790481622SDavid Gibson 218e7c4b0bfSAndy Whitcroft /* 21996822904SAndy Whitcroft * Region tracking -- allows tracking of reservations and instantiated pages 22096822904SAndy Whitcroft * across the pages in a mapping. 22184afd99bSAndy Whitcroft * 2221dd308a7SMike Kravetz * The region data structures are embedded into a resv_map and protected 2231dd308a7SMike Kravetz * by a resv_map's lock. The set of regions within the resv_map represent 2241dd308a7SMike Kravetz * reservations for huge pages, or huge pages that have already been 2251dd308a7SMike Kravetz * instantiated within the map. The from and to elements are huge page 2261dd308a7SMike Kravetz * indicies into the associated mapping. from indicates the starting index 2271dd308a7SMike Kravetz * of the region. to represents the first index past the end of the region. 2281dd308a7SMike Kravetz * 2291dd308a7SMike Kravetz * For example, a file region structure with from == 0 and to == 4 represents 2301dd308a7SMike Kravetz * four huge pages in a mapping. It is important to note that the to element 2311dd308a7SMike Kravetz * represents the first element past the end of the region. This is used in 2321dd308a7SMike Kravetz * arithmetic as 4(to) - 0(from) = 4 huge pages in the region. 2331dd308a7SMike Kravetz * 2341dd308a7SMike Kravetz * Interval notation of the form [from, to) will be used to indicate that 2351dd308a7SMike Kravetz * the endpoint from is inclusive and to is exclusive. 23696822904SAndy Whitcroft */ 23796822904SAndy Whitcroft struct file_region { 23896822904SAndy Whitcroft struct list_head link; 23996822904SAndy Whitcroft long from; 24096822904SAndy Whitcroft long to; 24196822904SAndy Whitcroft }; 24296822904SAndy Whitcroft 2431dd308a7SMike Kravetz /* 2441dd308a7SMike Kravetz * Add the huge page range represented by [f, t) to the reserve 2455e911373SMike Kravetz * map. In the normal case, existing regions will be expanded 2465e911373SMike Kravetz * to accommodate the specified range. Sufficient regions should 2475e911373SMike Kravetz * exist for expansion due to the previous call to region_chg 2485e911373SMike Kravetz * with the same range. However, it is possible that region_del 2495e911373SMike Kravetz * could have been called after region_chg and modifed the map 2505e911373SMike Kravetz * in such a way that no region exists to be expanded. In this 2515e911373SMike Kravetz * case, pull a region descriptor from the cache associated with 2525e911373SMike Kravetz * the map and use that for the new range. 253cf3ad20bSMike Kravetz * 254cf3ad20bSMike Kravetz * Return the number of new huge pages added to the map. This 255cf3ad20bSMike Kravetz * number is greater than or equal to zero. 2561dd308a7SMike Kravetz */ 2571406ec9bSJoonsoo Kim static long region_add(struct resv_map *resv, long f, long t) 25896822904SAndy Whitcroft { 2591406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 26096822904SAndy Whitcroft struct file_region *rg, *nrg, *trg; 261cf3ad20bSMike Kravetz long add = 0; 26296822904SAndy Whitcroft 2637b24d861SDavidlohr Bueso spin_lock(&resv->lock); 26496822904SAndy Whitcroft /* Locate the region we are either in or before. */ 26596822904SAndy Whitcroft list_for_each_entry(rg, head, link) 26696822904SAndy Whitcroft if (f <= rg->to) 26796822904SAndy Whitcroft break; 26896822904SAndy Whitcroft 2695e911373SMike Kravetz /* 2705e911373SMike Kravetz * If no region exists which can be expanded to include the 2715e911373SMike Kravetz * specified range, the list must have been modified by an 2725e911373SMike Kravetz * interleving call to region_del(). Pull a region descriptor 2735e911373SMike Kravetz * from the cache and use it for this range. 2745e911373SMike Kravetz */ 2755e911373SMike Kravetz if (&rg->link == head || t < rg->from) { 2765e911373SMike Kravetz VM_BUG_ON(resv->region_cache_count <= 0); 2775e911373SMike Kravetz 2785e911373SMike Kravetz resv->region_cache_count--; 2795e911373SMike Kravetz nrg = list_first_entry(&resv->region_cache, struct file_region, 2805e911373SMike Kravetz link); 2815e911373SMike Kravetz list_del(&nrg->link); 2825e911373SMike Kravetz 2835e911373SMike Kravetz nrg->from = f; 2845e911373SMike Kravetz nrg->to = t; 2855e911373SMike Kravetz list_add(&nrg->link, rg->link.prev); 2865e911373SMike Kravetz 2875e911373SMike Kravetz add += t - f; 2885e911373SMike Kravetz goto out_locked; 2895e911373SMike Kravetz } 2905e911373SMike Kravetz 29196822904SAndy Whitcroft /* Round our left edge to the current segment if it encloses us. */ 29296822904SAndy Whitcroft if (f > rg->from) 29396822904SAndy Whitcroft f = rg->from; 29496822904SAndy Whitcroft 29596822904SAndy Whitcroft /* Check for and consume any regions we now overlap with. */ 29696822904SAndy Whitcroft nrg = rg; 29796822904SAndy Whitcroft list_for_each_entry_safe(rg, trg, rg->link.prev, link) { 29896822904SAndy Whitcroft if (&rg->link == head) 29996822904SAndy Whitcroft break; 30096822904SAndy Whitcroft if (rg->from > t) 30196822904SAndy Whitcroft break; 30296822904SAndy Whitcroft 30396822904SAndy Whitcroft /* If this area reaches higher then extend our area to 30496822904SAndy Whitcroft * include it completely. If this is not the first area 30596822904SAndy Whitcroft * which we intend to reuse, free it. */ 30696822904SAndy Whitcroft if (rg->to > t) 30796822904SAndy Whitcroft t = rg->to; 30896822904SAndy Whitcroft if (rg != nrg) { 309cf3ad20bSMike Kravetz /* Decrement return value by the deleted range. 310cf3ad20bSMike Kravetz * Another range will span this area so that by 311cf3ad20bSMike Kravetz * end of routine add will be >= zero 312cf3ad20bSMike Kravetz */ 313cf3ad20bSMike Kravetz add -= (rg->to - rg->from); 31496822904SAndy Whitcroft list_del(&rg->link); 31596822904SAndy Whitcroft kfree(rg); 31696822904SAndy Whitcroft } 31796822904SAndy Whitcroft } 318cf3ad20bSMike Kravetz 319cf3ad20bSMike Kravetz add += (nrg->from - f); /* Added to beginning of region */ 32096822904SAndy Whitcroft nrg->from = f; 321cf3ad20bSMike Kravetz add += t - nrg->to; /* Added to end of region */ 32296822904SAndy Whitcroft nrg->to = t; 323cf3ad20bSMike Kravetz 3245e911373SMike Kravetz out_locked: 3255e911373SMike Kravetz resv->adds_in_progress--; 3267b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 327cf3ad20bSMike Kravetz VM_BUG_ON(add < 0); 328cf3ad20bSMike Kravetz return add; 32996822904SAndy Whitcroft } 33096822904SAndy Whitcroft 3311dd308a7SMike Kravetz /* 3321dd308a7SMike Kravetz * Examine the existing reserve map and determine how many 3331dd308a7SMike Kravetz * huge pages in the specified range [f, t) are NOT currently 3341dd308a7SMike Kravetz * represented. This routine is called before a subsequent 3351dd308a7SMike Kravetz * call to region_add that will actually modify the reserve 3361dd308a7SMike Kravetz * map to add the specified range [f, t). region_chg does 3371dd308a7SMike Kravetz * not change the number of huge pages represented by the 3381dd308a7SMike Kravetz * map. However, if the existing regions in the map can not 3391dd308a7SMike Kravetz * be expanded to represent the new range, a new file_region 3401dd308a7SMike Kravetz * structure is added to the map as a placeholder. This is 3411dd308a7SMike Kravetz * so that the subsequent region_add call will have all the 3421dd308a7SMike Kravetz * regions it needs and will not fail. 3431dd308a7SMike Kravetz * 3445e911373SMike Kravetz * Upon entry, region_chg will also examine the cache of region descriptors 3455e911373SMike Kravetz * associated with the map. If there are not enough descriptors cached, one 3465e911373SMike Kravetz * will be allocated for the in progress add operation. 3475e911373SMike Kravetz * 3485e911373SMike Kravetz * Returns the number of huge pages that need to be added to the existing 3495e911373SMike Kravetz * reservation map for the range [f, t). This number is greater or equal to 3505e911373SMike Kravetz * zero. -ENOMEM is returned if a new file_region structure or cache entry 3515e911373SMike Kravetz * is needed and can not be allocated. 3521dd308a7SMike Kravetz */ 3531406ec9bSJoonsoo Kim static long region_chg(struct resv_map *resv, long f, long t) 35496822904SAndy Whitcroft { 3551406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 3567b24d861SDavidlohr Bueso struct file_region *rg, *nrg = NULL; 35796822904SAndy Whitcroft long chg = 0; 35896822904SAndy Whitcroft 3597b24d861SDavidlohr Bueso retry: 3607b24d861SDavidlohr Bueso spin_lock(&resv->lock); 3615e911373SMike Kravetz retry_locked: 3625e911373SMike Kravetz resv->adds_in_progress++; 3635e911373SMike Kravetz 3645e911373SMike Kravetz /* 3655e911373SMike Kravetz * Check for sufficient descriptors in the cache to accommodate 3665e911373SMike Kravetz * the number of in progress add operations. 3675e911373SMike Kravetz */ 3685e911373SMike Kravetz if (resv->adds_in_progress > resv->region_cache_count) { 3695e911373SMike Kravetz struct file_region *trg; 3705e911373SMike Kravetz 3715e911373SMike Kravetz VM_BUG_ON(resv->adds_in_progress - resv->region_cache_count > 1); 3725e911373SMike Kravetz /* Must drop lock to allocate a new descriptor. */ 3735e911373SMike Kravetz resv->adds_in_progress--; 3745e911373SMike Kravetz spin_unlock(&resv->lock); 3755e911373SMike Kravetz 3765e911373SMike Kravetz trg = kmalloc(sizeof(*trg), GFP_KERNEL); 377dbe409e4SMike Kravetz if (!trg) { 378dbe409e4SMike Kravetz kfree(nrg); 3795e911373SMike Kravetz return -ENOMEM; 380dbe409e4SMike Kravetz } 3815e911373SMike Kravetz 3825e911373SMike Kravetz spin_lock(&resv->lock); 3835e911373SMike Kravetz list_add(&trg->link, &resv->region_cache); 3845e911373SMike Kravetz resv->region_cache_count++; 3855e911373SMike Kravetz goto retry_locked; 3865e911373SMike Kravetz } 3875e911373SMike Kravetz 38896822904SAndy Whitcroft /* Locate the region we are before or in. */ 38996822904SAndy Whitcroft list_for_each_entry(rg, head, link) 39096822904SAndy Whitcroft if (f <= rg->to) 39196822904SAndy Whitcroft break; 39296822904SAndy Whitcroft 39396822904SAndy Whitcroft /* If we are below the current region then a new region is required. 39496822904SAndy Whitcroft * Subtle, allocate a new region at the position but make it zero 39596822904SAndy Whitcroft * size such that we can guarantee to record the reservation. */ 39696822904SAndy Whitcroft if (&rg->link == head || t < rg->from) { 3977b24d861SDavidlohr Bueso if (!nrg) { 3985e911373SMike Kravetz resv->adds_in_progress--; 3997b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 40096822904SAndy Whitcroft nrg = kmalloc(sizeof(*nrg), GFP_KERNEL); 40196822904SAndy Whitcroft if (!nrg) 40296822904SAndy Whitcroft return -ENOMEM; 4037b24d861SDavidlohr Bueso 40496822904SAndy Whitcroft nrg->from = f; 40596822904SAndy Whitcroft nrg->to = f; 40696822904SAndy Whitcroft INIT_LIST_HEAD(&nrg->link); 4077b24d861SDavidlohr Bueso goto retry; 4087b24d861SDavidlohr Bueso } 40996822904SAndy Whitcroft 4107b24d861SDavidlohr Bueso list_add(&nrg->link, rg->link.prev); 4117b24d861SDavidlohr Bueso chg = t - f; 4127b24d861SDavidlohr Bueso goto out_nrg; 41396822904SAndy Whitcroft } 41496822904SAndy Whitcroft 41596822904SAndy Whitcroft /* Round our left edge to the current segment if it encloses us. */ 41696822904SAndy Whitcroft if (f > rg->from) 41796822904SAndy Whitcroft f = rg->from; 41896822904SAndy Whitcroft chg = t - f; 41996822904SAndy Whitcroft 42096822904SAndy Whitcroft /* Check for and consume any regions we now overlap with. */ 42196822904SAndy Whitcroft list_for_each_entry(rg, rg->link.prev, link) { 42296822904SAndy Whitcroft if (&rg->link == head) 42396822904SAndy Whitcroft break; 42496822904SAndy Whitcroft if (rg->from > t) 4257b24d861SDavidlohr Bueso goto out; 42696822904SAndy Whitcroft 42725985edcSLucas De Marchi /* We overlap with this area, if it extends further than 42896822904SAndy Whitcroft * us then we must extend ourselves. Account for its 42996822904SAndy Whitcroft * existing reservation. */ 43096822904SAndy Whitcroft if (rg->to > t) { 43196822904SAndy Whitcroft chg += rg->to - t; 43296822904SAndy Whitcroft t = rg->to; 43396822904SAndy Whitcroft } 43496822904SAndy Whitcroft chg -= rg->to - rg->from; 43596822904SAndy Whitcroft } 4367b24d861SDavidlohr Bueso 4377b24d861SDavidlohr Bueso out: 4387b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 4397b24d861SDavidlohr Bueso /* We already know we raced and no longer need the new region */ 4407b24d861SDavidlohr Bueso kfree(nrg); 4417b24d861SDavidlohr Bueso return chg; 4427b24d861SDavidlohr Bueso out_nrg: 4437b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 44496822904SAndy Whitcroft return chg; 44596822904SAndy Whitcroft } 44696822904SAndy Whitcroft 4471dd308a7SMike Kravetz /* 4485e911373SMike Kravetz * Abort the in progress add operation. The adds_in_progress field 4495e911373SMike Kravetz * of the resv_map keeps track of the operations in progress between 4505e911373SMike Kravetz * calls to region_chg and region_add. Operations are sometimes 4515e911373SMike Kravetz * aborted after the call to region_chg. In such cases, region_abort 4525e911373SMike Kravetz * is called to decrement the adds_in_progress counter. 4535e911373SMike Kravetz * 4545e911373SMike Kravetz * NOTE: The range arguments [f, t) are not needed or used in this 4555e911373SMike Kravetz * routine. They are kept to make reading the calling code easier as 4565e911373SMike Kravetz * arguments will match the associated region_chg call. 4575e911373SMike Kravetz */ 4585e911373SMike Kravetz static void region_abort(struct resv_map *resv, long f, long t) 4595e911373SMike Kravetz { 4605e911373SMike Kravetz spin_lock(&resv->lock); 4615e911373SMike Kravetz VM_BUG_ON(!resv->region_cache_count); 4625e911373SMike Kravetz resv->adds_in_progress--; 4635e911373SMike Kravetz spin_unlock(&resv->lock); 4645e911373SMike Kravetz } 4655e911373SMike Kravetz 4665e911373SMike Kravetz /* 467feba16e2SMike Kravetz * Delete the specified range [f, t) from the reserve map. If the 468feba16e2SMike Kravetz * t parameter is LONG_MAX, this indicates that ALL regions after f 469feba16e2SMike Kravetz * should be deleted. Locate the regions which intersect [f, t) 470feba16e2SMike Kravetz * and either trim, delete or split the existing regions. 471feba16e2SMike Kravetz * 472feba16e2SMike Kravetz * Returns the number of huge pages deleted from the reserve map. 473feba16e2SMike Kravetz * In the normal case, the return value is zero or more. In the 474feba16e2SMike Kravetz * case where a region must be split, a new region descriptor must 475feba16e2SMike Kravetz * be allocated. If the allocation fails, -ENOMEM will be returned. 476feba16e2SMike Kravetz * NOTE: If the parameter t == LONG_MAX, then we will never split 477feba16e2SMike Kravetz * a region and possibly return -ENOMEM. Callers specifying 478feba16e2SMike Kravetz * t == LONG_MAX do not need to check for -ENOMEM error. 4791dd308a7SMike Kravetz */ 480feba16e2SMike Kravetz static long region_del(struct resv_map *resv, long f, long t) 48196822904SAndy Whitcroft { 4821406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 48396822904SAndy Whitcroft struct file_region *rg, *trg; 484feba16e2SMike Kravetz struct file_region *nrg = NULL; 485feba16e2SMike Kravetz long del = 0; 48696822904SAndy Whitcroft 487feba16e2SMike Kravetz retry: 4887b24d861SDavidlohr Bueso spin_lock(&resv->lock); 489feba16e2SMike Kravetz list_for_each_entry_safe(rg, trg, head, link) { 490dbe409e4SMike Kravetz /* 491dbe409e4SMike Kravetz * Skip regions before the range to be deleted. file_region 492dbe409e4SMike Kravetz * ranges are normally of the form [from, to). However, there 493dbe409e4SMike Kravetz * may be a "placeholder" entry in the map which is of the form 494dbe409e4SMike Kravetz * (from, to) with from == to. Check for placeholder entries 495dbe409e4SMike Kravetz * at the beginning of the range to be deleted. 496dbe409e4SMike Kravetz */ 497dbe409e4SMike Kravetz if (rg->to <= f && (rg->to != rg->from || rg->to != f)) 498feba16e2SMike Kravetz continue; 499dbe409e4SMike Kravetz 500feba16e2SMike Kravetz if (rg->from >= t) 50196822904SAndy Whitcroft break; 50296822904SAndy Whitcroft 503feba16e2SMike Kravetz if (f > rg->from && t < rg->to) { /* Must split region */ 504feba16e2SMike Kravetz /* 505feba16e2SMike Kravetz * Check for an entry in the cache before dropping 506feba16e2SMike Kravetz * lock and attempting allocation. 507feba16e2SMike Kravetz */ 508feba16e2SMike Kravetz if (!nrg && 509feba16e2SMike Kravetz resv->region_cache_count > resv->adds_in_progress) { 510feba16e2SMike Kravetz nrg = list_first_entry(&resv->region_cache, 511feba16e2SMike Kravetz struct file_region, 512feba16e2SMike Kravetz link); 513feba16e2SMike Kravetz list_del(&nrg->link); 514feba16e2SMike Kravetz resv->region_cache_count--; 51596822904SAndy Whitcroft } 51696822904SAndy Whitcroft 517feba16e2SMike Kravetz if (!nrg) { 518feba16e2SMike Kravetz spin_unlock(&resv->lock); 519feba16e2SMike Kravetz nrg = kmalloc(sizeof(*nrg), GFP_KERNEL); 520feba16e2SMike Kravetz if (!nrg) 521feba16e2SMike Kravetz return -ENOMEM; 522feba16e2SMike Kravetz goto retry; 523feba16e2SMike Kravetz } 524feba16e2SMike Kravetz 525feba16e2SMike Kravetz del += t - f; 526feba16e2SMike Kravetz 527feba16e2SMike Kravetz /* New entry for end of split region */ 528feba16e2SMike Kravetz nrg->from = t; 529feba16e2SMike Kravetz nrg->to = rg->to; 530feba16e2SMike Kravetz INIT_LIST_HEAD(&nrg->link); 531feba16e2SMike Kravetz 532feba16e2SMike Kravetz /* Original entry is trimmed */ 533feba16e2SMike Kravetz rg->to = f; 534feba16e2SMike Kravetz 535feba16e2SMike Kravetz list_add(&nrg->link, &rg->link); 536feba16e2SMike Kravetz nrg = NULL; 53796822904SAndy Whitcroft break; 538feba16e2SMike Kravetz } 539feba16e2SMike Kravetz 540feba16e2SMike Kravetz if (f <= rg->from && t >= rg->to) { /* Remove entire region */ 541feba16e2SMike Kravetz del += rg->to - rg->from; 54296822904SAndy Whitcroft list_del(&rg->link); 54396822904SAndy Whitcroft kfree(rg); 544feba16e2SMike Kravetz continue; 54596822904SAndy Whitcroft } 5467b24d861SDavidlohr Bueso 547feba16e2SMike Kravetz if (f <= rg->from) { /* Trim beginning of region */ 548feba16e2SMike Kravetz del += t - rg->from; 549feba16e2SMike Kravetz rg->from = t; 550feba16e2SMike Kravetz } else { /* Trim end of region */ 551feba16e2SMike Kravetz del += rg->to - f; 552feba16e2SMike Kravetz rg->to = f; 553feba16e2SMike Kravetz } 554feba16e2SMike Kravetz } 555feba16e2SMike Kravetz 5567b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 557feba16e2SMike Kravetz kfree(nrg); 558feba16e2SMike Kravetz return del; 55996822904SAndy Whitcroft } 56096822904SAndy Whitcroft 5611dd308a7SMike Kravetz /* 562b5cec28dSMike Kravetz * A rare out of memory error was encountered which prevented removal of 563b5cec28dSMike Kravetz * the reserve map region for a page. The huge page itself was free'ed 564b5cec28dSMike Kravetz * and removed from the page cache. This routine will adjust the subpool 565b5cec28dSMike Kravetz * usage count, and the global reserve count if needed. By incrementing 566b5cec28dSMike Kravetz * these counts, the reserve map entry which could not be deleted will 567b5cec28dSMike Kravetz * appear as a "reserved" entry instead of simply dangling with incorrect 568b5cec28dSMike Kravetz * counts. 569b5cec28dSMike Kravetz */ 57072e2936cSzhong jiang void hugetlb_fix_reserve_counts(struct inode *inode) 571b5cec28dSMike Kravetz { 572b5cec28dSMike Kravetz struct hugepage_subpool *spool = subpool_inode(inode); 573b5cec28dSMike Kravetz long rsv_adjust; 574b5cec28dSMike Kravetz 575b5cec28dSMike Kravetz rsv_adjust = hugepage_subpool_get_pages(spool, 1); 57672e2936cSzhong jiang if (rsv_adjust) { 577b5cec28dSMike Kravetz struct hstate *h = hstate_inode(inode); 578b5cec28dSMike Kravetz 579b5cec28dSMike Kravetz hugetlb_acct_memory(h, 1); 580b5cec28dSMike Kravetz } 581b5cec28dSMike Kravetz } 582b5cec28dSMike Kravetz 583b5cec28dSMike Kravetz /* 5841dd308a7SMike Kravetz * Count and return the number of huge pages in the reserve map 5851dd308a7SMike Kravetz * that intersect with the range [f, t). 5861dd308a7SMike Kravetz */ 5871406ec9bSJoonsoo Kim static long region_count(struct resv_map *resv, long f, long t) 58884afd99bSAndy Whitcroft { 5891406ec9bSJoonsoo Kim struct list_head *head = &resv->regions; 59084afd99bSAndy Whitcroft struct file_region *rg; 59184afd99bSAndy Whitcroft long chg = 0; 59284afd99bSAndy Whitcroft 5937b24d861SDavidlohr Bueso spin_lock(&resv->lock); 59484afd99bSAndy Whitcroft /* Locate each segment we overlap with, and count that overlap. */ 59584afd99bSAndy Whitcroft list_for_each_entry(rg, head, link) { 596f2135a4aSWang Sheng-Hui long seg_from; 597f2135a4aSWang Sheng-Hui long seg_to; 59884afd99bSAndy Whitcroft 59984afd99bSAndy Whitcroft if (rg->to <= f) 60084afd99bSAndy Whitcroft continue; 60184afd99bSAndy Whitcroft if (rg->from >= t) 60284afd99bSAndy Whitcroft break; 60384afd99bSAndy Whitcroft 60484afd99bSAndy Whitcroft seg_from = max(rg->from, f); 60584afd99bSAndy Whitcroft seg_to = min(rg->to, t); 60684afd99bSAndy Whitcroft 60784afd99bSAndy Whitcroft chg += seg_to - seg_from; 60884afd99bSAndy Whitcroft } 6097b24d861SDavidlohr Bueso spin_unlock(&resv->lock); 61084afd99bSAndy Whitcroft 61184afd99bSAndy Whitcroft return chg; 61284afd99bSAndy Whitcroft } 61384afd99bSAndy Whitcroft 61496822904SAndy Whitcroft /* 615e7c4b0bfSAndy Whitcroft * Convert the address within this vma to the page offset within 616e7c4b0bfSAndy Whitcroft * the mapping, in pagecache page units; huge pages here. 617e7c4b0bfSAndy Whitcroft */ 618a5516438SAndi Kleen static pgoff_t vma_hugecache_offset(struct hstate *h, 619a5516438SAndi Kleen struct vm_area_struct *vma, unsigned long address) 620e7c4b0bfSAndy Whitcroft { 621a5516438SAndi Kleen return ((address - vma->vm_start) >> huge_page_shift(h)) + 622a5516438SAndi Kleen (vma->vm_pgoff >> huge_page_order(h)); 623e7c4b0bfSAndy Whitcroft } 624e7c4b0bfSAndy Whitcroft 6250fe6e20bSNaoya Horiguchi pgoff_t linear_hugepage_index(struct vm_area_struct *vma, 6260fe6e20bSNaoya Horiguchi unsigned long address) 6270fe6e20bSNaoya Horiguchi { 6280fe6e20bSNaoya Horiguchi return vma_hugecache_offset(hstate_vma(vma), vma, address); 6290fe6e20bSNaoya Horiguchi } 630dee41079SDan Williams EXPORT_SYMBOL_GPL(linear_hugepage_index); 6310fe6e20bSNaoya Horiguchi 63284afd99bSAndy Whitcroft /* 63308fba699SMel Gorman * Return the size of the pages allocated when backing a VMA. In the majority 63408fba699SMel Gorman * cases this will be same size as used by the page table entries. 63508fba699SMel Gorman */ 63608fba699SMel Gorman unsigned long vma_kernel_pagesize(struct vm_area_struct *vma) 63708fba699SMel Gorman { 63808fba699SMel Gorman struct hstate *hstate; 63908fba699SMel Gorman 64008fba699SMel Gorman if (!is_vm_hugetlb_page(vma)) 64108fba699SMel Gorman return PAGE_SIZE; 64208fba699SMel Gorman 64308fba699SMel Gorman hstate = hstate_vma(vma); 64408fba699SMel Gorman 6452415cf12SWanpeng Li return 1UL << huge_page_shift(hstate); 64608fba699SMel Gorman } 647f340ca0fSJoerg Roedel EXPORT_SYMBOL_GPL(vma_kernel_pagesize); 64808fba699SMel Gorman 64908fba699SMel Gorman /* 6503340289dSMel Gorman * Return the page size being used by the MMU to back a VMA. In the majority 6513340289dSMel Gorman * of cases, the page size used by the kernel matches the MMU size. On 6523340289dSMel Gorman * architectures where it differs, an architecture-specific version of this 6533340289dSMel Gorman * function is required. 6543340289dSMel Gorman */ 6553340289dSMel Gorman #ifndef vma_mmu_pagesize 6563340289dSMel Gorman unsigned long vma_mmu_pagesize(struct vm_area_struct *vma) 6573340289dSMel Gorman { 6583340289dSMel Gorman return vma_kernel_pagesize(vma); 6593340289dSMel Gorman } 6603340289dSMel Gorman #endif 6613340289dSMel Gorman 6623340289dSMel Gorman /* 66384afd99bSAndy Whitcroft * Flags for MAP_PRIVATE reservations. These are stored in the bottom 66484afd99bSAndy Whitcroft * bits of the reservation map pointer, which are always clear due to 66584afd99bSAndy Whitcroft * alignment. 66684afd99bSAndy Whitcroft */ 66784afd99bSAndy Whitcroft #define HPAGE_RESV_OWNER (1UL << 0) 66884afd99bSAndy Whitcroft #define HPAGE_RESV_UNMAPPED (1UL << 1) 66904f2cbe3SMel Gorman #define HPAGE_RESV_MASK (HPAGE_RESV_OWNER | HPAGE_RESV_UNMAPPED) 67084afd99bSAndy Whitcroft 671a1e78772SMel Gorman /* 672a1e78772SMel Gorman * These helpers are used to track how many pages are reserved for 673a1e78772SMel Gorman * faults in a MAP_PRIVATE mapping. Only the process that called mmap() 674a1e78772SMel Gorman * is guaranteed to have their future faults succeed. 675a1e78772SMel Gorman * 676a1e78772SMel Gorman * With the exception of reset_vma_resv_huge_pages() which is called at fork(), 677a1e78772SMel Gorman * the reserve counters are updated with the hugetlb_lock held. It is safe 678a1e78772SMel Gorman * to reset the VMA at fork() time as it is not in use yet and there is no 679a1e78772SMel Gorman * chance of the global counters getting corrupted as a result of the values. 68084afd99bSAndy Whitcroft * 68184afd99bSAndy Whitcroft * The private mapping reservation is represented in a subtly different 68284afd99bSAndy Whitcroft * manner to a shared mapping. A shared mapping has a region map associated 68384afd99bSAndy Whitcroft * with the underlying file, this region map represents the backing file 68484afd99bSAndy Whitcroft * pages which have ever had a reservation assigned which this persists even 68584afd99bSAndy Whitcroft * after the page is instantiated. A private mapping has a region map 68684afd99bSAndy Whitcroft * associated with the original mmap which is attached to all VMAs which 68784afd99bSAndy Whitcroft * reference it, this region map represents those offsets which have consumed 68884afd99bSAndy Whitcroft * reservation ie. where pages have been instantiated. 689a1e78772SMel Gorman */ 690e7c4b0bfSAndy Whitcroft static unsigned long get_vma_private_data(struct vm_area_struct *vma) 691e7c4b0bfSAndy Whitcroft { 692e7c4b0bfSAndy Whitcroft return (unsigned long)vma->vm_private_data; 693e7c4b0bfSAndy Whitcroft } 694e7c4b0bfSAndy Whitcroft 695e7c4b0bfSAndy Whitcroft static void set_vma_private_data(struct vm_area_struct *vma, 696e7c4b0bfSAndy Whitcroft unsigned long value) 697e7c4b0bfSAndy Whitcroft { 698e7c4b0bfSAndy Whitcroft vma->vm_private_data = (void *)value; 699e7c4b0bfSAndy Whitcroft } 700e7c4b0bfSAndy Whitcroft 7019119a41eSJoonsoo Kim struct resv_map *resv_map_alloc(void) 70284afd99bSAndy Whitcroft { 70384afd99bSAndy Whitcroft struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL); 7045e911373SMike Kravetz struct file_region *rg = kmalloc(sizeof(*rg), GFP_KERNEL); 7055e911373SMike Kravetz 7065e911373SMike Kravetz if (!resv_map || !rg) { 7075e911373SMike Kravetz kfree(resv_map); 7085e911373SMike Kravetz kfree(rg); 70984afd99bSAndy Whitcroft return NULL; 7105e911373SMike Kravetz } 71184afd99bSAndy Whitcroft 71284afd99bSAndy Whitcroft kref_init(&resv_map->refs); 7137b24d861SDavidlohr Bueso spin_lock_init(&resv_map->lock); 71484afd99bSAndy Whitcroft INIT_LIST_HEAD(&resv_map->regions); 71584afd99bSAndy Whitcroft 7165e911373SMike Kravetz resv_map->adds_in_progress = 0; 7175e911373SMike Kravetz 7185e911373SMike Kravetz INIT_LIST_HEAD(&resv_map->region_cache); 7195e911373SMike Kravetz list_add(&rg->link, &resv_map->region_cache); 7205e911373SMike Kravetz resv_map->region_cache_count = 1; 7215e911373SMike Kravetz 72284afd99bSAndy Whitcroft return resv_map; 72384afd99bSAndy Whitcroft } 72484afd99bSAndy Whitcroft 7259119a41eSJoonsoo Kim void resv_map_release(struct kref *ref) 72684afd99bSAndy Whitcroft { 72784afd99bSAndy Whitcroft struct resv_map *resv_map = container_of(ref, struct resv_map, refs); 7285e911373SMike Kravetz struct list_head *head = &resv_map->region_cache; 7295e911373SMike Kravetz struct file_region *rg, *trg; 73084afd99bSAndy Whitcroft 73184afd99bSAndy Whitcroft /* Clear out any active regions before we release the map. */ 732feba16e2SMike Kravetz region_del(resv_map, 0, LONG_MAX); 7335e911373SMike Kravetz 7345e911373SMike Kravetz /* ... and any entries left in the cache */ 7355e911373SMike Kravetz list_for_each_entry_safe(rg, trg, head, link) { 7365e911373SMike Kravetz list_del(&rg->link); 7375e911373SMike Kravetz kfree(rg); 7385e911373SMike Kravetz } 7395e911373SMike Kravetz 7405e911373SMike Kravetz VM_BUG_ON(resv_map->adds_in_progress); 7415e911373SMike Kravetz 74284afd99bSAndy Whitcroft kfree(resv_map); 74384afd99bSAndy Whitcroft } 74484afd99bSAndy Whitcroft 7454e35f483SJoonsoo Kim static inline struct resv_map *inode_resv_map(struct inode *inode) 7464e35f483SJoonsoo Kim { 7474e35f483SJoonsoo Kim return inode->i_mapping->private_data; 7484e35f483SJoonsoo Kim } 7494e35f483SJoonsoo Kim 75084afd99bSAndy Whitcroft static struct resv_map *vma_resv_map(struct vm_area_struct *vma) 751a1e78772SMel Gorman { 75281d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 7534e35f483SJoonsoo Kim if (vma->vm_flags & VM_MAYSHARE) { 7544e35f483SJoonsoo Kim struct address_space *mapping = vma->vm_file->f_mapping; 7554e35f483SJoonsoo Kim struct inode *inode = mapping->host; 7564e35f483SJoonsoo Kim 7574e35f483SJoonsoo Kim return inode_resv_map(inode); 7584e35f483SJoonsoo Kim 7594e35f483SJoonsoo Kim } else { 76084afd99bSAndy Whitcroft return (struct resv_map *)(get_vma_private_data(vma) & 76184afd99bSAndy Whitcroft ~HPAGE_RESV_MASK); 7624e35f483SJoonsoo Kim } 763a1e78772SMel Gorman } 764a1e78772SMel Gorman 76584afd99bSAndy Whitcroft static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map) 766a1e78772SMel Gorman { 76781d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 76881d1b09cSSasha Levin VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); 769a1e78772SMel Gorman 77084afd99bSAndy Whitcroft set_vma_private_data(vma, (get_vma_private_data(vma) & 77184afd99bSAndy Whitcroft HPAGE_RESV_MASK) | (unsigned long)map); 77204f2cbe3SMel Gorman } 77304f2cbe3SMel Gorman 77404f2cbe3SMel Gorman static void set_vma_resv_flags(struct vm_area_struct *vma, unsigned long flags) 77504f2cbe3SMel Gorman { 77681d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 77781d1b09cSSasha Levin VM_BUG_ON_VMA(vma->vm_flags & VM_MAYSHARE, vma); 778e7c4b0bfSAndy Whitcroft 779e7c4b0bfSAndy Whitcroft set_vma_private_data(vma, get_vma_private_data(vma) | flags); 78004f2cbe3SMel Gorman } 78104f2cbe3SMel Gorman 78204f2cbe3SMel Gorman static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag) 78304f2cbe3SMel Gorman { 78481d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 785e7c4b0bfSAndy Whitcroft 786e7c4b0bfSAndy Whitcroft return (get_vma_private_data(vma) & flag) != 0; 787a1e78772SMel Gorman } 788a1e78772SMel Gorman 78904f2cbe3SMel Gorman /* Reset counters to 0 and clear all HPAGE_RESV_* flags */ 790a1e78772SMel Gorman void reset_vma_resv_huge_pages(struct vm_area_struct *vma) 791a1e78772SMel Gorman { 79281d1b09cSSasha Levin VM_BUG_ON_VMA(!is_vm_hugetlb_page(vma), vma); 793f83a275dSMel Gorman if (!(vma->vm_flags & VM_MAYSHARE)) 794a1e78772SMel Gorman vma->vm_private_data = (void *)0; 795a1e78772SMel Gorman } 796a1e78772SMel Gorman 797a1e78772SMel Gorman /* Returns true if the VMA has associated reserve pages */ 798559ec2f8SNicholas Krause static bool vma_has_reserves(struct vm_area_struct *vma, long chg) 799a1e78772SMel Gorman { 800af0ed73eSJoonsoo Kim if (vma->vm_flags & VM_NORESERVE) { 801af0ed73eSJoonsoo Kim /* 802af0ed73eSJoonsoo Kim * This address is already reserved by other process(chg == 0), 803af0ed73eSJoonsoo Kim * so, we should decrement reserved count. Without decrementing, 804af0ed73eSJoonsoo Kim * reserve count remains after releasing inode, because this 805af0ed73eSJoonsoo Kim * allocated page will go into page cache and is regarded as 806af0ed73eSJoonsoo Kim * coming from reserved pool in releasing step. Currently, we 807af0ed73eSJoonsoo Kim * don't have any other solution to deal with this situation 808af0ed73eSJoonsoo Kim * properly, so add work-around here. 809af0ed73eSJoonsoo Kim */ 810af0ed73eSJoonsoo Kim if (vma->vm_flags & VM_MAYSHARE && chg == 0) 811559ec2f8SNicholas Krause return true; 812af0ed73eSJoonsoo Kim else 813559ec2f8SNicholas Krause return false; 814af0ed73eSJoonsoo Kim } 815a63884e9SJoonsoo Kim 816a63884e9SJoonsoo Kim /* Shared mappings always use reserves */ 8171fb1b0e9SMike Kravetz if (vma->vm_flags & VM_MAYSHARE) { 8181fb1b0e9SMike Kravetz /* 8191fb1b0e9SMike Kravetz * We know VM_NORESERVE is not set. Therefore, there SHOULD 8201fb1b0e9SMike Kravetz * be a region map for all pages. The only situation where 8211fb1b0e9SMike Kravetz * there is no region map is if a hole was punched via 8221fb1b0e9SMike Kravetz * fallocate. In this case, there really are no reverves to 8231fb1b0e9SMike Kravetz * use. This situation is indicated if chg != 0. 8241fb1b0e9SMike Kravetz */ 8251fb1b0e9SMike Kravetz if (chg) 8261fb1b0e9SMike Kravetz return false; 8271fb1b0e9SMike Kravetz else 828559ec2f8SNicholas Krause return true; 8291fb1b0e9SMike Kravetz } 830a63884e9SJoonsoo Kim 831a63884e9SJoonsoo Kim /* 832a63884e9SJoonsoo Kim * Only the process that called mmap() has reserves for 833a63884e9SJoonsoo Kim * private mappings. 834a63884e9SJoonsoo Kim */ 83567961f9dSMike Kravetz if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { 83667961f9dSMike Kravetz /* 83767961f9dSMike Kravetz * Like the shared case above, a hole punch or truncate 83867961f9dSMike Kravetz * could have been performed on the private mapping. 83967961f9dSMike Kravetz * Examine the value of chg to determine if reserves 84067961f9dSMike Kravetz * actually exist or were previously consumed. 84167961f9dSMike Kravetz * Very Subtle - The value of chg comes from a previous 84267961f9dSMike Kravetz * call to vma_needs_reserves(). The reserve map for 84367961f9dSMike Kravetz * private mappings has different (opposite) semantics 84467961f9dSMike Kravetz * than that of shared mappings. vma_needs_reserves() 84567961f9dSMike Kravetz * has already taken this difference in semantics into 84667961f9dSMike Kravetz * account. Therefore, the meaning of chg is the same 84767961f9dSMike Kravetz * as in the shared case above. Code could easily be 84867961f9dSMike Kravetz * combined, but keeping it separate draws attention to 84967961f9dSMike Kravetz * subtle differences. 85067961f9dSMike Kravetz */ 85167961f9dSMike Kravetz if (chg) 85267961f9dSMike Kravetz return false; 85367961f9dSMike Kravetz else 854559ec2f8SNicholas Krause return true; 85567961f9dSMike Kravetz } 856a63884e9SJoonsoo Kim 857559ec2f8SNicholas Krause return false; 858a1e78772SMel Gorman } 859a1e78772SMel Gorman 860a5516438SAndi Kleen static void enqueue_huge_page(struct hstate *h, struct page *page) 8611da177e4SLinus Torvalds { 8621da177e4SLinus Torvalds int nid = page_to_nid(page); 8630edaecfaSAneesh Kumar K.V list_move(&page->lru, &h->hugepage_freelists[nid]); 864a5516438SAndi Kleen h->free_huge_pages++; 865a5516438SAndi Kleen h->free_huge_pages_node[nid]++; 8661da177e4SLinus Torvalds } 8671da177e4SLinus Torvalds 868bf50bab2SNaoya Horiguchi static struct page *dequeue_huge_page_node(struct hstate *h, int nid) 869bf50bab2SNaoya Horiguchi { 870bf50bab2SNaoya Horiguchi struct page *page; 871bf50bab2SNaoya Horiguchi 872c8721bbbSNaoya Horiguchi list_for_each_entry(page, &h->hugepage_freelists[nid], lru) 873c8721bbbSNaoya Horiguchi if (!is_migrate_isolate_page(page)) 874c8721bbbSNaoya Horiguchi break; 875c8721bbbSNaoya Horiguchi /* 876c8721bbbSNaoya Horiguchi * if 'non-isolated free hugepage' not found on the list, 877c8721bbbSNaoya Horiguchi * the allocation fails. 878c8721bbbSNaoya Horiguchi */ 879c8721bbbSNaoya Horiguchi if (&h->hugepage_freelists[nid] == &page->lru) 880bf50bab2SNaoya Horiguchi return NULL; 8810edaecfaSAneesh Kumar K.V list_move(&page->lru, &h->hugepage_activelist); 882a9869b83SNaoya Horiguchi set_page_refcounted(page); 883bf50bab2SNaoya Horiguchi h->free_huge_pages--; 884bf50bab2SNaoya Horiguchi h->free_huge_pages_node[nid]--; 885bf50bab2SNaoya Horiguchi return page; 886bf50bab2SNaoya Horiguchi } 887bf50bab2SNaoya Horiguchi 88886cdb465SNaoya Horiguchi /* Movability of hugepages depends on migration support. */ 88986cdb465SNaoya Horiguchi static inline gfp_t htlb_alloc_mask(struct hstate *h) 89086cdb465SNaoya Horiguchi { 891100873d7SNaoya Horiguchi if (hugepages_treat_as_movable || hugepage_migration_supported(h)) 89286cdb465SNaoya Horiguchi return GFP_HIGHUSER_MOVABLE; 89386cdb465SNaoya Horiguchi else 89486cdb465SNaoya Horiguchi return GFP_HIGHUSER; 89586cdb465SNaoya Horiguchi } 89686cdb465SNaoya Horiguchi 897a5516438SAndi Kleen static struct page *dequeue_huge_page_vma(struct hstate *h, 898a5516438SAndi Kleen struct vm_area_struct *vma, 899af0ed73eSJoonsoo Kim unsigned long address, int avoid_reserve, 900af0ed73eSJoonsoo Kim long chg) 9011da177e4SLinus Torvalds { 902b1c12cbcSKonstantin Khlebnikov struct page *page = NULL; 903480eccf9SLee Schermerhorn struct mempolicy *mpol; 90419770b32SMel Gorman nodemask_t *nodemask; 905c0ff7453SMiao Xie struct zonelist *zonelist; 906dd1a239fSMel Gorman struct zone *zone; 907dd1a239fSMel Gorman struct zoneref *z; 908cc9a6c87SMel Gorman unsigned int cpuset_mems_cookie; 9091da177e4SLinus Torvalds 910a1e78772SMel Gorman /* 911a1e78772SMel Gorman * A child process with MAP_PRIVATE mappings created by their parent 912a1e78772SMel Gorman * have no page reserves. This check ensures that reservations are 913a1e78772SMel Gorman * not "stolen". The child may still get SIGKILLed 914a1e78772SMel Gorman */ 915af0ed73eSJoonsoo Kim if (!vma_has_reserves(vma, chg) && 916a5516438SAndi Kleen h->free_huge_pages - h->resv_huge_pages == 0) 917c0ff7453SMiao Xie goto err; 918a1e78772SMel Gorman 91904f2cbe3SMel Gorman /* If reserves cannot be used, ensure enough pages are in the pool */ 920a5516438SAndi Kleen if (avoid_reserve && h->free_huge_pages - h->resv_huge_pages == 0) 9216eab04a8SJustin P. Mattock goto err; 92204f2cbe3SMel Gorman 9239966c4bbSJoonsoo Kim retry_cpuset: 924d26914d1SMel Gorman cpuset_mems_cookie = read_mems_allowed_begin(); 9259966c4bbSJoonsoo Kim zonelist = huge_zonelist(vma, address, 92686cdb465SNaoya Horiguchi htlb_alloc_mask(h), &mpol, &nodemask); 9279966c4bbSJoonsoo Kim 92819770b32SMel Gorman for_each_zone_zonelist_nodemask(zone, z, zonelist, 92919770b32SMel Gorman MAX_NR_ZONES - 1, nodemask) { 930344736f2SVladimir Davydov if (cpuset_zone_allowed(zone, htlb_alloc_mask(h))) { 931bf50bab2SNaoya Horiguchi page = dequeue_huge_page_node(h, zone_to_nid(zone)); 932bf50bab2SNaoya Horiguchi if (page) { 933af0ed73eSJoonsoo Kim if (avoid_reserve) 934af0ed73eSJoonsoo Kim break; 935af0ed73eSJoonsoo Kim if (!vma_has_reserves(vma, chg)) 936af0ed73eSJoonsoo Kim break; 937af0ed73eSJoonsoo Kim 93807443a85SJoonsoo Kim SetPagePrivate(page); 939a63884e9SJoonsoo Kim h->resv_huge_pages--; 9405ab3ee7bSKen Chen break; 9411da177e4SLinus Torvalds } 9423abf7afdSAndrew Morton } 943bf50bab2SNaoya Horiguchi } 944cc9a6c87SMel Gorman 945cc9a6c87SMel Gorman mpol_cond_put(mpol); 946d26914d1SMel Gorman if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie))) 947cc9a6c87SMel Gorman goto retry_cpuset; 948cc9a6c87SMel Gorman return page; 949cc9a6c87SMel Gorman 950c0ff7453SMiao Xie err: 951cc9a6c87SMel Gorman return NULL; 9521da177e4SLinus Torvalds } 9531da177e4SLinus Torvalds 9541cac6f2cSLuiz Capitulino /* 9551cac6f2cSLuiz Capitulino * common helper functions for hstate_next_node_to_{alloc|free}. 9561cac6f2cSLuiz Capitulino * We may have allocated or freed a huge page based on a different 9571cac6f2cSLuiz Capitulino * nodes_allowed previously, so h->next_node_to_{alloc|free} might 9581cac6f2cSLuiz Capitulino * be outside of *nodes_allowed. Ensure that we use an allowed 9591cac6f2cSLuiz Capitulino * node for alloc or free. 9601cac6f2cSLuiz Capitulino */ 9611cac6f2cSLuiz Capitulino static int next_node_allowed(int nid, nodemask_t *nodes_allowed) 9621cac6f2cSLuiz Capitulino { 9630edaf86cSAndrew Morton nid = next_node_in(nid, *nodes_allowed); 9641cac6f2cSLuiz Capitulino VM_BUG_ON(nid >= MAX_NUMNODES); 9651cac6f2cSLuiz Capitulino 9661cac6f2cSLuiz Capitulino return nid; 9671cac6f2cSLuiz Capitulino } 9681cac6f2cSLuiz Capitulino 9691cac6f2cSLuiz Capitulino static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed) 9701cac6f2cSLuiz Capitulino { 9711cac6f2cSLuiz Capitulino if (!node_isset(nid, *nodes_allowed)) 9721cac6f2cSLuiz Capitulino nid = next_node_allowed(nid, nodes_allowed); 9731cac6f2cSLuiz Capitulino return nid; 9741cac6f2cSLuiz Capitulino } 9751cac6f2cSLuiz Capitulino 9761cac6f2cSLuiz Capitulino /* 9771cac6f2cSLuiz Capitulino * returns the previously saved node ["this node"] from which to 9781cac6f2cSLuiz Capitulino * allocate a persistent huge page for the pool and advance the 9791cac6f2cSLuiz Capitulino * next node from which to allocate, handling wrap at end of node 9801cac6f2cSLuiz Capitulino * mask. 9811cac6f2cSLuiz Capitulino */ 9821cac6f2cSLuiz Capitulino static int hstate_next_node_to_alloc(struct hstate *h, 9831cac6f2cSLuiz Capitulino nodemask_t *nodes_allowed) 9841cac6f2cSLuiz Capitulino { 9851cac6f2cSLuiz Capitulino int nid; 9861cac6f2cSLuiz Capitulino 9871cac6f2cSLuiz Capitulino VM_BUG_ON(!nodes_allowed); 9881cac6f2cSLuiz Capitulino 9891cac6f2cSLuiz Capitulino nid = get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed); 9901cac6f2cSLuiz Capitulino h->next_nid_to_alloc = next_node_allowed(nid, nodes_allowed); 9911cac6f2cSLuiz Capitulino 9921cac6f2cSLuiz Capitulino return nid; 9931cac6f2cSLuiz Capitulino } 9941cac6f2cSLuiz Capitulino 9951cac6f2cSLuiz Capitulino /* 9961cac6f2cSLuiz Capitulino * helper for free_pool_huge_page() - return the previously saved 9971cac6f2cSLuiz Capitulino * node ["this node"] from which to free a huge page. Advance the 9981cac6f2cSLuiz Capitulino * next node id whether or not we find a free huge page to free so 9991cac6f2cSLuiz Capitulino * that the next attempt to free addresses the next node. 10001cac6f2cSLuiz Capitulino */ 10011cac6f2cSLuiz Capitulino static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed) 10021cac6f2cSLuiz Capitulino { 10031cac6f2cSLuiz Capitulino int nid; 10041cac6f2cSLuiz Capitulino 10051cac6f2cSLuiz Capitulino VM_BUG_ON(!nodes_allowed); 10061cac6f2cSLuiz Capitulino 10071cac6f2cSLuiz Capitulino nid = get_valid_node_allowed(h->next_nid_to_free, nodes_allowed); 10081cac6f2cSLuiz Capitulino h->next_nid_to_free = next_node_allowed(nid, nodes_allowed); 10091cac6f2cSLuiz Capitulino 10101cac6f2cSLuiz Capitulino return nid; 10111cac6f2cSLuiz Capitulino } 10121cac6f2cSLuiz Capitulino 10131cac6f2cSLuiz Capitulino #define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask) \ 10141cac6f2cSLuiz Capitulino for (nr_nodes = nodes_weight(*mask); \ 10151cac6f2cSLuiz Capitulino nr_nodes > 0 && \ 10161cac6f2cSLuiz Capitulino ((node = hstate_next_node_to_alloc(hs, mask)) || 1); \ 10171cac6f2cSLuiz Capitulino nr_nodes--) 10181cac6f2cSLuiz Capitulino 10191cac6f2cSLuiz Capitulino #define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \ 10201cac6f2cSLuiz Capitulino for (nr_nodes = nodes_weight(*mask); \ 10211cac6f2cSLuiz Capitulino nr_nodes > 0 && \ 10221cac6f2cSLuiz Capitulino ((node = hstate_next_node_to_free(hs, mask)) || 1); \ 10231cac6f2cSLuiz Capitulino nr_nodes--) 10241cac6f2cSLuiz Capitulino 1025461a7184SYisheng Xie #if defined(CONFIG_ARCH_HAS_GIGANTIC_PAGE) && \ 1026d08de8e2SGerald Schaefer ((defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || \ 1027d08de8e2SGerald Schaefer defined(CONFIG_CMA)) 1028944d9fecSLuiz Capitulino static void destroy_compound_gigantic_page(struct page *page, 1029d00181b9SKirill A. Shutemov unsigned int order) 1030944d9fecSLuiz Capitulino { 1031944d9fecSLuiz Capitulino int i; 1032944d9fecSLuiz Capitulino int nr_pages = 1 << order; 1033944d9fecSLuiz Capitulino struct page *p = page + 1; 1034944d9fecSLuiz Capitulino 1035c8cc708aSGerald Schaefer atomic_set(compound_mapcount_ptr(page), 0); 1036944d9fecSLuiz Capitulino for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { 10371d798ca3SKirill A. Shutemov clear_compound_head(p); 1038944d9fecSLuiz Capitulino set_page_refcounted(p); 1039944d9fecSLuiz Capitulino } 1040944d9fecSLuiz Capitulino 1041944d9fecSLuiz Capitulino set_compound_order(page, 0); 1042944d9fecSLuiz Capitulino __ClearPageHead(page); 1043944d9fecSLuiz Capitulino } 1044944d9fecSLuiz Capitulino 1045d00181b9SKirill A. Shutemov static void free_gigantic_page(struct page *page, unsigned int order) 1046944d9fecSLuiz Capitulino { 1047944d9fecSLuiz Capitulino free_contig_range(page_to_pfn(page), 1 << order); 1048944d9fecSLuiz Capitulino } 1049944d9fecSLuiz Capitulino 1050944d9fecSLuiz Capitulino static int __alloc_gigantic_page(unsigned long start_pfn, 1051944d9fecSLuiz Capitulino unsigned long nr_pages) 1052944d9fecSLuiz Capitulino { 1053944d9fecSLuiz Capitulino unsigned long end_pfn = start_pfn + nr_pages; 1054944d9fecSLuiz Capitulino return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE); 1055944d9fecSLuiz Capitulino } 1056944d9fecSLuiz Capitulino 1057f44b2ddaSJoonsoo Kim static bool pfn_range_valid_gigantic(struct zone *z, 1058f44b2ddaSJoonsoo Kim unsigned long start_pfn, unsigned long nr_pages) 1059944d9fecSLuiz Capitulino { 1060944d9fecSLuiz Capitulino unsigned long i, end_pfn = start_pfn + nr_pages; 1061944d9fecSLuiz Capitulino struct page *page; 1062944d9fecSLuiz Capitulino 1063944d9fecSLuiz Capitulino for (i = start_pfn; i < end_pfn; i++) { 1064944d9fecSLuiz Capitulino if (!pfn_valid(i)) 1065944d9fecSLuiz Capitulino return false; 1066944d9fecSLuiz Capitulino 1067944d9fecSLuiz Capitulino page = pfn_to_page(i); 1068944d9fecSLuiz Capitulino 1069f44b2ddaSJoonsoo Kim if (page_zone(page) != z) 1070f44b2ddaSJoonsoo Kim return false; 1071f44b2ddaSJoonsoo Kim 1072944d9fecSLuiz Capitulino if (PageReserved(page)) 1073944d9fecSLuiz Capitulino return false; 1074944d9fecSLuiz Capitulino 1075944d9fecSLuiz Capitulino if (page_count(page) > 0) 1076944d9fecSLuiz Capitulino return false; 1077944d9fecSLuiz Capitulino 1078944d9fecSLuiz Capitulino if (PageHuge(page)) 1079944d9fecSLuiz Capitulino return false; 1080944d9fecSLuiz Capitulino } 1081944d9fecSLuiz Capitulino 1082944d9fecSLuiz Capitulino return true; 1083944d9fecSLuiz Capitulino } 1084944d9fecSLuiz Capitulino 1085944d9fecSLuiz Capitulino static bool zone_spans_last_pfn(const struct zone *zone, 1086944d9fecSLuiz Capitulino unsigned long start_pfn, unsigned long nr_pages) 1087944d9fecSLuiz Capitulino { 1088944d9fecSLuiz Capitulino unsigned long last_pfn = start_pfn + nr_pages - 1; 1089944d9fecSLuiz Capitulino return zone_spans_pfn(zone, last_pfn); 1090944d9fecSLuiz Capitulino } 1091944d9fecSLuiz Capitulino 1092d00181b9SKirill A. Shutemov static struct page *alloc_gigantic_page(int nid, unsigned int order) 1093944d9fecSLuiz Capitulino { 1094944d9fecSLuiz Capitulino unsigned long nr_pages = 1 << order; 1095944d9fecSLuiz Capitulino unsigned long ret, pfn, flags; 1096944d9fecSLuiz Capitulino struct zone *z; 1097944d9fecSLuiz Capitulino 1098944d9fecSLuiz Capitulino z = NODE_DATA(nid)->node_zones; 1099944d9fecSLuiz Capitulino for (; z - NODE_DATA(nid)->node_zones < MAX_NR_ZONES; z++) { 1100944d9fecSLuiz Capitulino spin_lock_irqsave(&z->lock, flags); 1101944d9fecSLuiz Capitulino 1102944d9fecSLuiz Capitulino pfn = ALIGN(z->zone_start_pfn, nr_pages); 1103944d9fecSLuiz Capitulino while (zone_spans_last_pfn(z, pfn, nr_pages)) { 1104f44b2ddaSJoonsoo Kim if (pfn_range_valid_gigantic(z, pfn, nr_pages)) { 1105944d9fecSLuiz Capitulino /* 1106944d9fecSLuiz Capitulino * We release the zone lock here because 1107944d9fecSLuiz Capitulino * alloc_contig_range() will also lock the zone 1108944d9fecSLuiz Capitulino * at some point. If there's an allocation 1109944d9fecSLuiz Capitulino * spinning on this lock, it may win the race 1110944d9fecSLuiz Capitulino * and cause alloc_contig_range() to fail... 1111944d9fecSLuiz Capitulino */ 1112944d9fecSLuiz Capitulino spin_unlock_irqrestore(&z->lock, flags); 1113944d9fecSLuiz Capitulino ret = __alloc_gigantic_page(pfn, nr_pages); 1114944d9fecSLuiz Capitulino if (!ret) 1115944d9fecSLuiz Capitulino return pfn_to_page(pfn); 1116944d9fecSLuiz Capitulino spin_lock_irqsave(&z->lock, flags); 1117944d9fecSLuiz Capitulino } 1118944d9fecSLuiz Capitulino pfn += nr_pages; 1119944d9fecSLuiz Capitulino } 1120944d9fecSLuiz Capitulino 1121944d9fecSLuiz Capitulino spin_unlock_irqrestore(&z->lock, flags); 1122944d9fecSLuiz Capitulino } 1123944d9fecSLuiz Capitulino 1124944d9fecSLuiz Capitulino return NULL; 1125944d9fecSLuiz Capitulino } 1126944d9fecSLuiz Capitulino 1127944d9fecSLuiz Capitulino static void prep_new_huge_page(struct hstate *h, struct page *page, int nid); 1128d00181b9SKirill A. Shutemov static void prep_compound_gigantic_page(struct page *page, unsigned int order); 1129944d9fecSLuiz Capitulino 1130944d9fecSLuiz Capitulino static struct page *alloc_fresh_gigantic_page_node(struct hstate *h, int nid) 1131944d9fecSLuiz Capitulino { 1132944d9fecSLuiz Capitulino struct page *page; 1133944d9fecSLuiz Capitulino 1134944d9fecSLuiz Capitulino page = alloc_gigantic_page(nid, huge_page_order(h)); 1135944d9fecSLuiz Capitulino if (page) { 1136944d9fecSLuiz Capitulino prep_compound_gigantic_page(page, huge_page_order(h)); 1137944d9fecSLuiz Capitulino prep_new_huge_page(h, page, nid); 1138944d9fecSLuiz Capitulino } 1139944d9fecSLuiz Capitulino 1140944d9fecSLuiz Capitulino return page; 1141944d9fecSLuiz Capitulino } 1142944d9fecSLuiz Capitulino 1143944d9fecSLuiz Capitulino static int alloc_fresh_gigantic_page(struct hstate *h, 1144944d9fecSLuiz Capitulino nodemask_t *nodes_allowed) 1145944d9fecSLuiz Capitulino { 1146944d9fecSLuiz Capitulino struct page *page = NULL; 1147944d9fecSLuiz Capitulino int nr_nodes, node; 1148944d9fecSLuiz Capitulino 1149944d9fecSLuiz Capitulino for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { 1150944d9fecSLuiz Capitulino page = alloc_fresh_gigantic_page_node(h, node); 1151944d9fecSLuiz Capitulino if (page) 1152944d9fecSLuiz Capitulino return 1; 1153944d9fecSLuiz Capitulino } 1154944d9fecSLuiz Capitulino 1155944d9fecSLuiz Capitulino return 0; 1156944d9fecSLuiz Capitulino } 1157944d9fecSLuiz Capitulino 1158944d9fecSLuiz Capitulino static inline bool gigantic_page_supported(void) { return true; } 1159944d9fecSLuiz Capitulino #else 1160944d9fecSLuiz Capitulino static inline bool gigantic_page_supported(void) { return false; } 1161d00181b9SKirill A. Shutemov static inline void free_gigantic_page(struct page *page, unsigned int order) { } 1162944d9fecSLuiz Capitulino static inline void destroy_compound_gigantic_page(struct page *page, 1163d00181b9SKirill A. Shutemov unsigned int order) { } 1164944d9fecSLuiz Capitulino static inline int alloc_fresh_gigantic_page(struct hstate *h, 1165944d9fecSLuiz Capitulino nodemask_t *nodes_allowed) { return 0; } 1166944d9fecSLuiz Capitulino #endif 1167944d9fecSLuiz Capitulino 1168a5516438SAndi Kleen static void update_and_free_page(struct hstate *h, struct page *page) 11696af2acb6SAdam Litke { 11706af2acb6SAdam Litke int i; 1171a5516438SAndi Kleen 1172944d9fecSLuiz Capitulino if (hstate_is_gigantic(h) && !gigantic_page_supported()) 1173944d9fecSLuiz Capitulino return; 117418229df5SAndy Whitcroft 1175a5516438SAndi Kleen h->nr_huge_pages--; 1176a5516438SAndi Kleen h->nr_huge_pages_node[page_to_nid(page)]--; 1177a5516438SAndi Kleen for (i = 0; i < pages_per_huge_page(h); i++) { 117832f84528SChris Forbes page[i].flags &= ~(1 << PG_locked | 1 << PG_error | 117932f84528SChris Forbes 1 << PG_referenced | 1 << PG_dirty | 1180a7407a27SLuiz Capitulino 1 << PG_active | 1 << PG_private | 1181a7407a27SLuiz Capitulino 1 << PG_writeback); 11826af2acb6SAdam Litke } 1183309381feSSasha Levin VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page), page); 1184f1e61557SKirill A. Shutemov set_compound_page_dtor(page, NULL_COMPOUND_DTOR); 11856af2acb6SAdam Litke set_page_refcounted(page); 1186944d9fecSLuiz Capitulino if (hstate_is_gigantic(h)) { 1187944d9fecSLuiz Capitulino destroy_compound_gigantic_page(page, huge_page_order(h)); 1188944d9fecSLuiz Capitulino free_gigantic_page(page, huge_page_order(h)); 1189944d9fecSLuiz Capitulino } else { 1190a5516438SAndi Kleen __free_pages(page, huge_page_order(h)); 11916af2acb6SAdam Litke } 1192944d9fecSLuiz Capitulino } 11936af2acb6SAdam Litke 1194e5ff2159SAndi Kleen struct hstate *size_to_hstate(unsigned long size) 1195e5ff2159SAndi Kleen { 1196e5ff2159SAndi Kleen struct hstate *h; 1197e5ff2159SAndi Kleen 1198e5ff2159SAndi Kleen for_each_hstate(h) { 1199e5ff2159SAndi Kleen if (huge_page_size(h) == size) 1200e5ff2159SAndi Kleen return h; 1201e5ff2159SAndi Kleen } 1202e5ff2159SAndi Kleen return NULL; 1203e5ff2159SAndi Kleen } 1204e5ff2159SAndi Kleen 1205bcc54222SNaoya Horiguchi /* 1206bcc54222SNaoya Horiguchi * Test to determine whether the hugepage is "active/in-use" (i.e. being linked 1207bcc54222SNaoya Horiguchi * to hstate->hugepage_activelist.) 1208bcc54222SNaoya Horiguchi * 1209bcc54222SNaoya Horiguchi * This function can be called for tail pages, but never returns true for them. 1210bcc54222SNaoya Horiguchi */ 1211bcc54222SNaoya Horiguchi bool page_huge_active(struct page *page) 1212bcc54222SNaoya Horiguchi { 1213bcc54222SNaoya Horiguchi VM_BUG_ON_PAGE(!PageHuge(page), page); 1214bcc54222SNaoya Horiguchi return PageHead(page) && PagePrivate(&page[1]); 1215bcc54222SNaoya Horiguchi } 1216bcc54222SNaoya Horiguchi 1217bcc54222SNaoya Horiguchi /* never called for tail page */ 1218bcc54222SNaoya Horiguchi static void set_page_huge_active(struct page *page) 1219bcc54222SNaoya Horiguchi { 1220bcc54222SNaoya Horiguchi VM_BUG_ON_PAGE(!PageHeadHuge(page), page); 1221bcc54222SNaoya Horiguchi SetPagePrivate(&page[1]); 1222bcc54222SNaoya Horiguchi } 1223bcc54222SNaoya Horiguchi 1224bcc54222SNaoya Horiguchi static void clear_page_huge_active(struct page *page) 1225bcc54222SNaoya Horiguchi { 1226bcc54222SNaoya Horiguchi VM_BUG_ON_PAGE(!PageHeadHuge(page), page); 1227bcc54222SNaoya Horiguchi ClearPagePrivate(&page[1]); 1228bcc54222SNaoya Horiguchi } 1229bcc54222SNaoya Horiguchi 12308f1d26d0SAtsushi Kumagai void free_huge_page(struct page *page) 123127a85ef1SDavid Gibson { 1232a5516438SAndi Kleen /* 1233a5516438SAndi Kleen * Can't pass hstate in here because it is called from the 1234a5516438SAndi Kleen * compound page destructor. 1235a5516438SAndi Kleen */ 1236e5ff2159SAndi Kleen struct hstate *h = page_hstate(page); 12377893d1d5SAdam Litke int nid = page_to_nid(page); 123890481622SDavid Gibson struct hugepage_subpool *spool = 123990481622SDavid Gibson (struct hugepage_subpool *)page_private(page); 124007443a85SJoonsoo Kim bool restore_reserve; 124127a85ef1SDavid Gibson 1242e5df70abSAndy Whitcroft set_page_private(page, 0); 124323be7468SMel Gorman page->mapping = NULL; 1244b4330afbSMike Kravetz VM_BUG_ON_PAGE(page_count(page), page); 1245b4330afbSMike Kravetz VM_BUG_ON_PAGE(page_mapcount(page), page); 124607443a85SJoonsoo Kim restore_reserve = PagePrivate(page); 124716c794b4SJoonsoo Kim ClearPagePrivate(page); 124827a85ef1SDavid Gibson 12491c5ecae3SMike Kravetz /* 12501c5ecae3SMike Kravetz * A return code of zero implies that the subpool will be under its 12511c5ecae3SMike Kravetz * minimum size if the reservation is not restored after page is free. 12521c5ecae3SMike Kravetz * Therefore, force restore_reserve operation. 12531c5ecae3SMike Kravetz */ 12541c5ecae3SMike Kravetz if (hugepage_subpool_put_pages(spool, 1) == 0) 12551c5ecae3SMike Kravetz restore_reserve = true; 12561c5ecae3SMike Kravetz 125727a85ef1SDavid Gibson spin_lock(&hugetlb_lock); 1258bcc54222SNaoya Horiguchi clear_page_huge_active(page); 12596d76dcf4SAneesh Kumar K.V hugetlb_cgroup_uncharge_page(hstate_index(h), 12606d76dcf4SAneesh Kumar K.V pages_per_huge_page(h), page); 126107443a85SJoonsoo Kim if (restore_reserve) 126207443a85SJoonsoo Kim h->resv_huge_pages++; 126307443a85SJoonsoo Kim 1264944d9fecSLuiz Capitulino if (h->surplus_huge_pages_node[nid]) { 12650edaecfaSAneesh Kumar K.V /* remove the page from active list */ 12660edaecfaSAneesh Kumar K.V list_del(&page->lru); 1267a5516438SAndi Kleen update_and_free_page(h, page); 1268a5516438SAndi Kleen h->surplus_huge_pages--; 1269a5516438SAndi Kleen h->surplus_huge_pages_node[nid]--; 12707893d1d5SAdam Litke } else { 12715d3a551cSWill Deacon arch_clear_hugepage_flags(page); 1272a5516438SAndi Kleen enqueue_huge_page(h, page); 12737893d1d5SAdam Litke } 127427a85ef1SDavid Gibson spin_unlock(&hugetlb_lock); 127527a85ef1SDavid Gibson } 127627a85ef1SDavid Gibson 1277a5516438SAndi Kleen static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) 1278b7ba30c6SAndi Kleen { 12790edaecfaSAneesh Kumar K.V INIT_LIST_HEAD(&page->lru); 1280f1e61557SKirill A. Shutemov set_compound_page_dtor(page, HUGETLB_PAGE_DTOR); 1281b7ba30c6SAndi Kleen spin_lock(&hugetlb_lock); 12829dd540e2SAneesh Kumar K.V set_hugetlb_cgroup(page, NULL); 1283a5516438SAndi Kleen h->nr_huge_pages++; 1284a5516438SAndi Kleen h->nr_huge_pages_node[nid]++; 1285b7ba30c6SAndi Kleen spin_unlock(&hugetlb_lock); 1286b7ba30c6SAndi Kleen put_page(page); /* free it into the hugepage allocator */ 1287b7ba30c6SAndi Kleen } 1288b7ba30c6SAndi Kleen 1289d00181b9SKirill A. Shutemov static void prep_compound_gigantic_page(struct page *page, unsigned int order) 129020a0307cSWu Fengguang { 129120a0307cSWu Fengguang int i; 129220a0307cSWu Fengguang int nr_pages = 1 << order; 129320a0307cSWu Fengguang struct page *p = page + 1; 129420a0307cSWu Fengguang 129520a0307cSWu Fengguang /* we rely on prep_new_huge_page to set the destructor */ 129620a0307cSWu Fengguang set_compound_order(page, order); 1297ef5a22beSAndrea Arcangeli __ClearPageReserved(page); 1298de09d31dSKirill A. Shutemov __SetPageHead(page); 129920a0307cSWu Fengguang for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { 1300ef5a22beSAndrea Arcangeli /* 1301ef5a22beSAndrea Arcangeli * For gigantic hugepages allocated through bootmem at 1302ef5a22beSAndrea Arcangeli * boot, it's safer to be consistent with the not-gigantic 1303ef5a22beSAndrea Arcangeli * hugepages and clear the PG_reserved bit from all tail pages 1304ef5a22beSAndrea Arcangeli * too. Otherwse drivers using get_user_pages() to access tail 1305ef5a22beSAndrea Arcangeli * pages may get the reference counting wrong if they see 1306ef5a22beSAndrea Arcangeli * PG_reserved set on a tail page (despite the head page not 1307ef5a22beSAndrea Arcangeli * having PG_reserved set). Enforcing this consistency between 1308ef5a22beSAndrea Arcangeli * head and tail pages allows drivers to optimize away a check 1309ef5a22beSAndrea Arcangeli * on the head page when they need know if put_page() is needed 1310ef5a22beSAndrea Arcangeli * after get_user_pages(). 1311ef5a22beSAndrea Arcangeli */ 1312ef5a22beSAndrea Arcangeli __ClearPageReserved(p); 131358a84aa9SYouquan Song set_page_count(p, 0); 13141d798ca3SKirill A. Shutemov set_compound_head(p, page); 131520a0307cSWu Fengguang } 1316b4330afbSMike Kravetz atomic_set(compound_mapcount_ptr(page), -1); 131720a0307cSWu Fengguang } 131820a0307cSWu Fengguang 13197795912cSAndrew Morton /* 13207795912cSAndrew Morton * PageHuge() only returns true for hugetlbfs pages, but not for normal or 13217795912cSAndrew Morton * transparent huge pages. See the PageTransHuge() documentation for more 13227795912cSAndrew Morton * details. 13237795912cSAndrew Morton */ 132420a0307cSWu Fengguang int PageHuge(struct page *page) 132520a0307cSWu Fengguang { 132620a0307cSWu Fengguang if (!PageCompound(page)) 132720a0307cSWu Fengguang return 0; 132820a0307cSWu Fengguang 132920a0307cSWu Fengguang page = compound_head(page); 1330f1e61557SKirill A. Shutemov return page[1].compound_dtor == HUGETLB_PAGE_DTOR; 133120a0307cSWu Fengguang } 133243131e14SNaoya Horiguchi EXPORT_SYMBOL_GPL(PageHuge); 133343131e14SNaoya Horiguchi 133427c73ae7SAndrea Arcangeli /* 133527c73ae7SAndrea Arcangeli * PageHeadHuge() only returns true for hugetlbfs head page, but not for 133627c73ae7SAndrea Arcangeli * normal or transparent huge pages. 133727c73ae7SAndrea Arcangeli */ 133827c73ae7SAndrea Arcangeli int PageHeadHuge(struct page *page_head) 133927c73ae7SAndrea Arcangeli { 134027c73ae7SAndrea Arcangeli if (!PageHead(page_head)) 134127c73ae7SAndrea Arcangeli return 0; 134227c73ae7SAndrea Arcangeli 1343758f66a2SAndrew Morton return get_compound_page_dtor(page_head) == free_huge_page; 134427c73ae7SAndrea Arcangeli } 134527c73ae7SAndrea Arcangeli 134613d60f4bSZhang Yi pgoff_t __basepage_index(struct page *page) 134713d60f4bSZhang Yi { 134813d60f4bSZhang Yi struct page *page_head = compound_head(page); 134913d60f4bSZhang Yi pgoff_t index = page_index(page_head); 135013d60f4bSZhang Yi unsigned long compound_idx; 135113d60f4bSZhang Yi 135213d60f4bSZhang Yi if (!PageHuge(page_head)) 135313d60f4bSZhang Yi return page_index(page); 135413d60f4bSZhang Yi 135513d60f4bSZhang Yi if (compound_order(page_head) >= MAX_ORDER) 135613d60f4bSZhang Yi compound_idx = page_to_pfn(page) - page_to_pfn(page_head); 135713d60f4bSZhang Yi else 135813d60f4bSZhang Yi compound_idx = page - page_head; 135913d60f4bSZhang Yi 136013d60f4bSZhang Yi return (index << compound_order(page_head)) + compound_idx; 136113d60f4bSZhang Yi } 136213d60f4bSZhang Yi 1363a5516438SAndi Kleen static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) 13641da177e4SLinus Torvalds { 13651da177e4SLinus Torvalds struct page *page; 1366f96efd58SJoe Jin 136796db800fSVlastimil Babka page = __alloc_pages_node(nid, 136886cdb465SNaoya Horiguchi htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE| 1369551883aeSNishanth Aravamudan __GFP_REPEAT|__GFP_NOWARN, 1370a5516438SAndi Kleen huge_page_order(h)); 13711da177e4SLinus Torvalds if (page) { 1372a5516438SAndi Kleen prep_new_huge_page(h, page, nid); 13731da177e4SLinus Torvalds } 137463b4613cSNishanth Aravamudan 137563b4613cSNishanth Aravamudan return page; 137663b4613cSNishanth Aravamudan } 137763b4613cSNishanth Aravamudan 1378b2261026SJoonsoo Kim static int alloc_fresh_huge_page(struct hstate *h, nodemask_t *nodes_allowed) 1379b2261026SJoonsoo Kim { 1380b2261026SJoonsoo Kim struct page *page; 1381b2261026SJoonsoo Kim int nr_nodes, node; 1382b2261026SJoonsoo Kim int ret = 0; 1383b2261026SJoonsoo Kim 1384b2261026SJoonsoo Kim for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { 1385b2261026SJoonsoo Kim page = alloc_fresh_huge_page_node(h, node); 1386b2261026SJoonsoo Kim if (page) { 1387b2261026SJoonsoo Kim ret = 1; 1388b2261026SJoonsoo Kim break; 1389b2261026SJoonsoo Kim } 1390b2261026SJoonsoo Kim } 1391b2261026SJoonsoo Kim 1392b2261026SJoonsoo Kim if (ret) 1393b2261026SJoonsoo Kim count_vm_event(HTLB_BUDDY_PGALLOC); 1394b2261026SJoonsoo Kim else 1395b2261026SJoonsoo Kim count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); 1396b2261026SJoonsoo Kim 1397b2261026SJoonsoo Kim return ret; 1398b2261026SJoonsoo Kim } 1399b2261026SJoonsoo Kim 1400e8c5c824SLee Schermerhorn /* 1401e8c5c824SLee Schermerhorn * Free huge page from pool from next node to free. 1402e8c5c824SLee Schermerhorn * Attempt to keep persistent huge pages more or less 1403e8c5c824SLee Schermerhorn * balanced over allowed nodes. 1404e8c5c824SLee Schermerhorn * Called with hugetlb_lock locked. 1405e8c5c824SLee Schermerhorn */ 14066ae11b27SLee Schermerhorn static int free_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed, 14076ae11b27SLee Schermerhorn bool acct_surplus) 1408e8c5c824SLee Schermerhorn { 1409b2261026SJoonsoo Kim int nr_nodes, node; 1410e8c5c824SLee Schermerhorn int ret = 0; 1411e8c5c824SLee Schermerhorn 1412b2261026SJoonsoo Kim for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { 1413685f3457SLee Schermerhorn /* 1414685f3457SLee Schermerhorn * If we're returning unused surplus pages, only examine 1415685f3457SLee Schermerhorn * nodes with surplus pages. 1416685f3457SLee Schermerhorn */ 1417b2261026SJoonsoo Kim if ((!acct_surplus || h->surplus_huge_pages_node[node]) && 1418b2261026SJoonsoo Kim !list_empty(&h->hugepage_freelists[node])) { 1419e8c5c824SLee Schermerhorn struct page *page = 1420b2261026SJoonsoo Kim list_entry(h->hugepage_freelists[node].next, 1421e8c5c824SLee Schermerhorn struct page, lru); 1422e8c5c824SLee Schermerhorn list_del(&page->lru); 1423e8c5c824SLee Schermerhorn h->free_huge_pages--; 1424b2261026SJoonsoo Kim h->free_huge_pages_node[node]--; 1425685f3457SLee Schermerhorn if (acct_surplus) { 1426685f3457SLee Schermerhorn h->surplus_huge_pages--; 1427b2261026SJoonsoo Kim h->surplus_huge_pages_node[node]--; 1428685f3457SLee Schermerhorn } 1429e8c5c824SLee Schermerhorn update_and_free_page(h, page); 1430e8c5c824SLee Schermerhorn ret = 1; 14319a76db09SLee Schermerhorn break; 1432e8c5c824SLee Schermerhorn } 1433b2261026SJoonsoo Kim } 1434e8c5c824SLee Schermerhorn 1435e8c5c824SLee Schermerhorn return ret; 1436e8c5c824SLee Schermerhorn } 1437e8c5c824SLee Schermerhorn 1438c8721bbbSNaoya Horiguchi /* 1439c8721bbbSNaoya Horiguchi * Dissolve a given free hugepage into free buddy pages. This function does 1440082d5b6bSGerald Schaefer * nothing for in-use (including surplus) hugepages. Returns -EBUSY if the 1441082d5b6bSGerald Schaefer * number of free hugepages would be reduced below the number of reserved 1442082d5b6bSGerald Schaefer * hugepages. 1443c8721bbbSNaoya Horiguchi */ 1444082d5b6bSGerald Schaefer static int dissolve_free_huge_page(struct page *page) 1445c8721bbbSNaoya Horiguchi { 1446082d5b6bSGerald Schaefer int rc = 0; 1447082d5b6bSGerald Schaefer 1448c8721bbbSNaoya Horiguchi spin_lock(&hugetlb_lock); 1449c8721bbbSNaoya Horiguchi if (PageHuge(page) && !page_count(page)) { 14502247bb33SGerald Schaefer struct page *head = compound_head(page); 14512247bb33SGerald Schaefer struct hstate *h = page_hstate(head); 14522247bb33SGerald Schaefer int nid = page_to_nid(head); 1453082d5b6bSGerald Schaefer if (h->free_huge_pages - h->resv_huge_pages == 0) { 1454082d5b6bSGerald Schaefer rc = -EBUSY; 1455082d5b6bSGerald Schaefer goto out; 1456082d5b6bSGerald Schaefer } 14572247bb33SGerald Schaefer list_del(&head->lru); 1458c8721bbbSNaoya Horiguchi h->free_huge_pages--; 1459c8721bbbSNaoya Horiguchi h->free_huge_pages_node[nid]--; 1460c1470b33Szhong jiang h->max_huge_pages--; 14612247bb33SGerald Schaefer update_and_free_page(h, head); 1462c8721bbbSNaoya Horiguchi } 1463082d5b6bSGerald Schaefer out: 1464c8721bbbSNaoya Horiguchi spin_unlock(&hugetlb_lock); 1465082d5b6bSGerald Schaefer return rc; 1466c8721bbbSNaoya Horiguchi } 1467c8721bbbSNaoya Horiguchi 1468c8721bbbSNaoya Horiguchi /* 1469c8721bbbSNaoya Horiguchi * Dissolve free hugepages in a given pfn range. Used by memory hotplug to 1470c8721bbbSNaoya Horiguchi * make specified memory blocks removable from the system. 14712247bb33SGerald Schaefer * Note that this will dissolve a free gigantic hugepage completely, if any 14722247bb33SGerald Schaefer * part of it lies within the given range. 1473082d5b6bSGerald Schaefer * Also note that if dissolve_free_huge_page() returns with an error, all 1474082d5b6bSGerald Schaefer * free hugepages that were dissolved before that error are lost. 1475c8721bbbSNaoya Horiguchi */ 1476082d5b6bSGerald Schaefer int dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn) 1477c8721bbbSNaoya Horiguchi { 1478c8721bbbSNaoya Horiguchi unsigned long pfn; 1479eb03aa00SGerald Schaefer struct page *page; 1480082d5b6bSGerald Schaefer int rc = 0; 1481c8721bbbSNaoya Horiguchi 1482d0177639SLi Zhong if (!hugepages_supported()) 1483082d5b6bSGerald Schaefer return rc; 1484d0177639SLi Zhong 1485eb03aa00SGerald Schaefer for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << minimum_order) { 1486eb03aa00SGerald Schaefer page = pfn_to_page(pfn); 1487eb03aa00SGerald Schaefer if (PageHuge(page) && !page_count(page)) { 1488eb03aa00SGerald Schaefer rc = dissolve_free_huge_page(page); 1489eb03aa00SGerald Schaefer if (rc) 1490082d5b6bSGerald Schaefer break; 1491eb03aa00SGerald Schaefer } 1492eb03aa00SGerald Schaefer } 1493082d5b6bSGerald Schaefer 1494082d5b6bSGerald Schaefer return rc; 1495c8721bbbSNaoya Horiguchi } 1496c8721bbbSNaoya Horiguchi 1497099730d6SDave Hansen /* 1498099730d6SDave Hansen * There are 3 ways this can get called: 1499099730d6SDave Hansen * 1. With vma+addr: we use the VMA's memory policy 1500099730d6SDave Hansen * 2. With !vma, but nid=NUMA_NO_NODE: We try to allocate a huge 1501099730d6SDave Hansen * page from any node, and let the buddy allocator itself figure 1502099730d6SDave Hansen * it out. 1503099730d6SDave Hansen * 3. With !vma, but nid!=NUMA_NO_NODE. We allocate a huge page 1504099730d6SDave Hansen * strictly from 'nid' 1505099730d6SDave Hansen */ 1506099730d6SDave Hansen static struct page *__hugetlb_alloc_buddy_huge_page(struct hstate *h, 1507099730d6SDave Hansen struct vm_area_struct *vma, unsigned long addr, int nid) 1508099730d6SDave Hansen { 1509099730d6SDave Hansen int order = huge_page_order(h); 1510099730d6SDave Hansen gfp_t gfp = htlb_alloc_mask(h)|__GFP_COMP|__GFP_REPEAT|__GFP_NOWARN; 1511099730d6SDave Hansen unsigned int cpuset_mems_cookie; 1512099730d6SDave Hansen 1513099730d6SDave Hansen /* 1514099730d6SDave Hansen * We need a VMA to get a memory policy. If we do not 1515e0ec90eeSDave Hansen * have one, we use the 'nid' argument. 1516e0ec90eeSDave Hansen * 1517e0ec90eeSDave Hansen * The mempolicy stuff below has some non-inlined bits 1518e0ec90eeSDave Hansen * and calls ->vm_ops. That makes it hard to optimize at 1519e0ec90eeSDave Hansen * compile-time, even when NUMA is off and it does 1520e0ec90eeSDave Hansen * nothing. This helps the compiler optimize it out. 1521099730d6SDave Hansen */ 1522e0ec90eeSDave Hansen if (!IS_ENABLED(CONFIG_NUMA) || !vma) { 1523099730d6SDave Hansen /* 1524099730d6SDave Hansen * If a specific node is requested, make sure to 1525099730d6SDave Hansen * get memory from there, but only when a node 1526099730d6SDave Hansen * is explicitly specified. 1527099730d6SDave Hansen */ 1528099730d6SDave Hansen if (nid != NUMA_NO_NODE) 1529099730d6SDave Hansen gfp |= __GFP_THISNODE; 1530099730d6SDave Hansen /* 1531099730d6SDave Hansen * Make sure to call something that can handle 1532099730d6SDave Hansen * nid=NUMA_NO_NODE 1533099730d6SDave Hansen */ 1534099730d6SDave Hansen return alloc_pages_node(nid, gfp, order); 1535099730d6SDave Hansen } 1536099730d6SDave Hansen 1537099730d6SDave Hansen /* 1538099730d6SDave Hansen * OK, so we have a VMA. Fetch the mempolicy and try to 1539e0ec90eeSDave Hansen * allocate a huge page with it. We will only reach this 1540e0ec90eeSDave Hansen * when CONFIG_NUMA=y. 1541099730d6SDave Hansen */ 1542099730d6SDave Hansen do { 1543099730d6SDave Hansen struct page *page; 1544099730d6SDave Hansen struct mempolicy *mpol; 1545099730d6SDave Hansen struct zonelist *zl; 1546099730d6SDave Hansen nodemask_t *nodemask; 1547099730d6SDave Hansen 1548099730d6SDave Hansen cpuset_mems_cookie = read_mems_allowed_begin(); 1549099730d6SDave Hansen zl = huge_zonelist(vma, addr, gfp, &mpol, &nodemask); 1550099730d6SDave Hansen mpol_cond_put(mpol); 1551099730d6SDave Hansen page = __alloc_pages_nodemask(gfp, order, zl, nodemask); 1552099730d6SDave Hansen if (page) 1553099730d6SDave Hansen return page; 1554099730d6SDave Hansen } while (read_mems_allowed_retry(cpuset_mems_cookie)); 1555099730d6SDave Hansen 1556099730d6SDave Hansen return NULL; 1557099730d6SDave Hansen } 1558099730d6SDave Hansen 1559099730d6SDave Hansen /* 1560099730d6SDave Hansen * There are two ways to allocate a huge page: 1561099730d6SDave Hansen * 1. When you have a VMA and an address (like a fault) 1562099730d6SDave Hansen * 2. When you have no VMA (like when setting /proc/.../nr_hugepages) 1563099730d6SDave Hansen * 1564099730d6SDave Hansen * 'vma' and 'addr' are only for (1). 'nid' is always NUMA_NO_NODE in 1565099730d6SDave Hansen * this case which signifies that the allocation should be done with 1566099730d6SDave Hansen * respect for the VMA's memory policy. 1567099730d6SDave Hansen * 1568099730d6SDave Hansen * For (2), we ignore 'vma' and 'addr' and use 'nid' exclusively. This 1569099730d6SDave Hansen * implies that memory policies will not be taken in to account. 1570099730d6SDave Hansen */ 1571099730d6SDave Hansen static struct page *__alloc_buddy_huge_page(struct hstate *h, 1572099730d6SDave Hansen struct vm_area_struct *vma, unsigned long addr, int nid) 15737893d1d5SAdam Litke { 15747893d1d5SAdam Litke struct page *page; 1575bf50bab2SNaoya Horiguchi unsigned int r_nid; 15767893d1d5SAdam Litke 1577bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 1578aa888a74SAndi Kleen return NULL; 1579aa888a74SAndi Kleen 1580d1c3fb1fSNishanth Aravamudan /* 1581099730d6SDave Hansen * Make sure that anyone specifying 'nid' is not also specifying a VMA. 1582099730d6SDave Hansen * This makes sure the caller is picking _one_ of the modes with which 1583099730d6SDave Hansen * we can call this function, not both. 1584099730d6SDave Hansen */ 1585099730d6SDave Hansen if (vma || (addr != -1)) { 1586e0ec90eeSDave Hansen VM_WARN_ON_ONCE(addr == -1); 1587e0ec90eeSDave Hansen VM_WARN_ON_ONCE(nid != NUMA_NO_NODE); 1588099730d6SDave Hansen } 1589099730d6SDave Hansen /* 1590d1c3fb1fSNishanth Aravamudan * Assume we will successfully allocate the surplus page to 1591d1c3fb1fSNishanth Aravamudan * prevent racing processes from causing the surplus to exceed 1592d1c3fb1fSNishanth Aravamudan * overcommit 1593d1c3fb1fSNishanth Aravamudan * 1594d1c3fb1fSNishanth Aravamudan * This however introduces a different race, where a process B 1595d1c3fb1fSNishanth Aravamudan * tries to grow the static hugepage pool while alloc_pages() is 1596d1c3fb1fSNishanth Aravamudan * called by process A. B will only examine the per-node 1597d1c3fb1fSNishanth Aravamudan * counters in determining if surplus huge pages can be 1598d1c3fb1fSNishanth Aravamudan * converted to normal huge pages in adjust_pool_surplus(). A 1599d1c3fb1fSNishanth Aravamudan * won't be able to increment the per-node counter, until the 1600d1c3fb1fSNishanth Aravamudan * lock is dropped by B, but B doesn't drop hugetlb_lock until 1601d1c3fb1fSNishanth Aravamudan * no more huge pages can be converted from surplus to normal 1602d1c3fb1fSNishanth Aravamudan * state (and doesn't try to convert again). Thus, we have a 1603d1c3fb1fSNishanth Aravamudan * case where a surplus huge page exists, the pool is grown, and 1604d1c3fb1fSNishanth Aravamudan * the surplus huge page still exists after, even though it 1605d1c3fb1fSNishanth Aravamudan * should just have been converted to a normal huge page. This 1606d1c3fb1fSNishanth Aravamudan * does not leak memory, though, as the hugepage will be freed 1607d1c3fb1fSNishanth Aravamudan * once it is out of use. It also does not allow the counters to 1608d1c3fb1fSNishanth Aravamudan * go out of whack in adjust_pool_surplus() as we don't modify 1609d1c3fb1fSNishanth Aravamudan * the node values until we've gotten the hugepage and only the 1610d1c3fb1fSNishanth Aravamudan * per-node value is checked there. 1611d1c3fb1fSNishanth Aravamudan */ 1612d1c3fb1fSNishanth Aravamudan spin_lock(&hugetlb_lock); 1613a5516438SAndi Kleen if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) { 1614d1c3fb1fSNishanth Aravamudan spin_unlock(&hugetlb_lock); 1615d1c3fb1fSNishanth Aravamudan return NULL; 1616d1c3fb1fSNishanth Aravamudan } else { 1617a5516438SAndi Kleen h->nr_huge_pages++; 1618a5516438SAndi Kleen h->surplus_huge_pages++; 1619d1c3fb1fSNishanth Aravamudan } 1620d1c3fb1fSNishanth Aravamudan spin_unlock(&hugetlb_lock); 1621d1c3fb1fSNishanth Aravamudan 1622099730d6SDave Hansen page = __hugetlb_alloc_buddy_huge_page(h, vma, addr, nid); 1623d1c3fb1fSNishanth Aravamudan 16247893d1d5SAdam Litke spin_lock(&hugetlb_lock); 1625d1c3fb1fSNishanth Aravamudan if (page) { 16260edaecfaSAneesh Kumar K.V INIT_LIST_HEAD(&page->lru); 1627bf50bab2SNaoya Horiguchi r_nid = page_to_nid(page); 1628f1e61557SKirill A. Shutemov set_compound_page_dtor(page, HUGETLB_PAGE_DTOR); 16299dd540e2SAneesh Kumar K.V set_hugetlb_cgroup(page, NULL); 1630d1c3fb1fSNishanth Aravamudan /* 1631d1c3fb1fSNishanth Aravamudan * We incremented the global counters already 1632d1c3fb1fSNishanth Aravamudan */ 1633bf50bab2SNaoya Horiguchi h->nr_huge_pages_node[r_nid]++; 1634bf50bab2SNaoya Horiguchi h->surplus_huge_pages_node[r_nid]++; 16353b116300SAdam Litke __count_vm_event(HTLB_BUDDY_PGALLOC); 1636d1c3fb1fSNishanth Aravamudan } else { 1637a5516438SAndi Kleen h->nr_huge_pages--; 1638a5516438SAndi Kleen h->surplus_huge_pages--; 16393b116300SAdam Litke __count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); 16407893d1d5SAdam Litke } 1641d1c3fb1fSNishanth Aravamudan spin_unlock(&hugetlb_lock); 16427893d1d5SAdam Litke 16437893d1d5SAdam Litke return page; 16447893d1d5SAdam Litke } 16457893d1d5SAdam Litke 1646e4e574b7SAdam Litke /* 1647099730d6SDave Hansen * Allocate a huge page from 'nid'. Note, 'nid' may be 1648099730d6SDave Hansen * NUMA_NO_NODE, which means that it may be allocated 1649099730d6SDave Hansen * anywhere. 1650099730d6SDave Hansen */ 1651e0ec90eeSDave Hansen static 1652099730d6SDave Hansen struct page *__alloc_buddy_huge_page_no_mpol(struct hstate *h, int nid) 1653099730d6SDave Hansen { 1654099730d6SDave Hansen unsigned long addr = -1; 1655099730d6SDave Hansen 1656099730d6SDave Hansen return __alloc_buddy_huge_page(h, NULL, addr, nid); 1657099730d6SDave Hansen } 1658099730d6SDave Hansen 1659099730d6SDave Hansen /* 1660099730d6SDave Hansen * Use the VMA's mpolicy to allocate a huge page from the buddy. 1661099730d6SDave Hansen */ 1662e0ec90eeSDave Hansen static 1663099730d6SDave Hansen struct page *__alloc_buddy_huge_page_with_mpol(struct hstate *h, 1664099730d6SDave Hansen struct vm_area_struct *vma, unsigned long addr) 1665099730d6SDave Hansen { 1666099730d6SDave Hansen return __alloc_buddy_huge_page(h, vma, addr, NUMA_NO_NODE); 1667099730d6SDave Hansen } 1668099730d6SDave Hansen 1669099730d6SDave Hansen /* 1670bf50bab2SNaoya Horiguchi * This allocation function is useful in the context where vma is irrelevant. 1671bf50bab2SNaoya Horiguchi * E.g. soft-offlining uses this function because it only cares physical 1672bf50bab2SNaoya Horiguchi * address of error page. 1673bf50bab2SNaoya Horiguchi */ 1674bf50bab2SNaoya Horiguchi struct page *alloc_huge_page_node(struct hstate *h, int nid) 1675bf50bab2SNaoya Horiguchi { 16764ef91848SJoonsoo Kim struct page *page = NULL; 1677bf50bab2SNaoya Horiguchi 1678bf50bab2SNaoya Horiguchi spin_lock(&hugetlb_lock); 16794ef91848SJoonsoo Kim if (h->free_huge_pages - h->resv_huge_pages > 0) 1680bf50bab2SNaoya Horiguchi page = dequeue_huge_page_node(h, nid); 1681bf50bab2SNaoya Horiguchi spin_unlock(&hugetlb_lock); 1682bf50bab2SNaoya Horiguchi 168394ae8ba7SAneesh Kumar K.V if (!page) 1684099730d6SDave Hansen page = __alloc_buddy_huge_page_no_mpol(h, nid); 1685bf50bab2SNaoya Horiguchi 1686bf50bab2SNaoya Horiguchi return page; 1687bf50bab2SNaoya Horiguchi } 1688bf50bab2SNaoya Horiguchi 1689bf50bab2SNaoya Horiguchi /* 169025985edcSLucas De Marchi * Increase the hugetlb pool such that it can accommodate a reservation 1691e4e574b7SAdam Litke * of size 'delta'. 1692e4e574b7SAdam Litke */ 1693a5516438SAndi Kleen static int gather_surplus_pages(struct hstate *h, int delta) 1694e4e574b7SAdam Litke { 1695e4e574b7SAdam Litke struct list_head surplus_list; 1696e4e574b7SAdam Litke struct page *page, *tmp; 1697e4e574b7SAdam Litke int ret, i; 1698e4e574b7SAdam Litke int needed, allocated; 169928073b02SHillf Danton bool alloc_ok = true; 1700e4e574b7SAdam Litke 1701a5516438SAndi Kleen needed = (h->resv_huge_pages + delta) - h->free_huge_pages; 1702ac09b3a1SAdam Litke if (needed <= 0) { 1703a5516438SAndi Kleen h->resv_huge_pages += delta; 1704e4e574b7SAdam Litke return 0; 1705ac09b3a1SAdam Litke } 1706e4e574b7SAdam Litke 1707e4e574b7SAdam Litke allocated = 0; 1708e4e574b7SAdam Litke INIT_LIST_HEAD(&surplus_list); 1709e4e574b7SAdam Litke 1710e4e574b7SAdam Litke ret = -ENOMEM; 1711e4e574b7SAdam Litke retry: 1712e4e574b7SAdam Litke spin_unlock(&hugetlb_lock); 1713e4e574b7SAdam Litke for (i = 0; i < needed; i++) { 1714099730d6SDave Hansen page = __alloc_buddy_huge_page_no_mpol(h, NUMA_NO_NODE); 171528073b02SHillf Danton if (!page) { 171628073b02SHillf Danton alloc_ok = false; 171728073b02SHillf Danton break; 171828073b02SHillf Danton } 1719e4e574b7SAdam Litke list_add(&page->lru, &surplus_list); 1720e4e574b7SAdam Litke } 172128073b02SHillf Danton allocated += i; 1722e4e574b7SAdam Litke 1723e4e574b7SAdam Litke /* 1724e4e574b7SAdam Litke * After retaking hugetlb_lock, we need to recalculate 'needed' 1725e4e574b7SAdam Litke * because either resv_huge_pages or free_huge_pages may have changed. 1726e4e574b7SAdam Litke */ 1727e4e574b7SAdam Litke spin_lock(&hugetlb_lock); 1728a5516438SAndi Kleen needed = (h->resv_huge_pages + delta) - 1729a5516438SAndi Kleen (h->free_huge_pages + allocated); 173028073b02SHillf Danton if (needed > 0) { 173128073b02SHillf Danton if (alloc_ok) 1732e4e574b7SAdam Litke goto retry; 173328073b02SHillf Danton /* 173428073b02SHillf Danton * We were not able to allocate enough pages to 173528073b02SHillf Danton * satisfy the entire reservation so we free what 173628073b02SHillf Danton * we've allocated so far. 173728073b02SHillf Danton */ 173828073b02SHillf Danton goto free; 173928073b02SHillf Danton } 1740e4e574b7SAdam Litke /* 1741e4e574b7SAdam Litke * The surplus_list now contains _at_least_ the number of extra pages 174225985edcSLucas De Marchi * needed to accommodate the reservation. Add the appropriate number 1743e4e574b7SAdam Litke * of pages to the hugetlb pool and free the extras back to the buddy 1744ac09b3a1SAdam Litke * allocator. Commit the entire reservation here to prevent another 1745ac09b3a1SAdam Litke * process from stealing the pages as they are added to the pool but 1746ac09b3a1SAdam Litke * before they are reserved. 1747e4e574b7SAdam Litke */ 1748e4e574b7SAdam Litke needed += allocated; 1749a5516438SAndi Kleen h->resv_huge_pages += delta; 1750e4e574b7SAdam Litke ret = 0; 1751a9869b83SNaoya Horiguchi 175219fc3f0aSAdam Litke /* Free the needed pages to the hugetlb pool */ 175319fc3f0aSAdam Litke list_for_each_entry_safe(page, tmp, &surplus_list, lru) { 175419fc3f0aSAdam Litke if ((--needed) < 0) 175519fc3f0aSAdam Litke break; 1756a9869b83SNaoya Horiguchi /* 1757a9869b83SNaoya Horiguchi * This page is now managed by the hugetlb allocator and has 1758a9869b83SNaoya Horiguchi * no users -- drop the buddy allocator's reference. 1759a9869b83SNaoya Horiguchi */ 1760a9869b83SNaoya Horiguchi put_page_testzero(page); 1761309381feSSasha Levin VM_BUG_ON_PAGE(page_count(page), page); 1762a5516438SAndi Kleen enqueue_huge_page(h, page); 176319fc3f0aSAdam Litke } 176428073b02SHillf Danton free: 1765b0365c8dSHillf Danton spin_unlock(&hugetlb_lock); 176619fc3f0aSAdam Litke 176719fc3f0aSAdam Litke /* Free unnecessary surplus pages to the buddy allocator */ 1768c0d934baSJoonsoo Kim list_for_each_entry_safe(page, tmp, &surplus_list, lru) 1769a9869b83SNaoya Horiguchi put_page(page); 177019fc3f0aSAdam Litke spin_lock(&hugetlb_lock); 1771e4e574b7SAdam Litke 1772e4e574b7SAdam Litke return ret; 1773e4e574b7SAdam Litke } 1774e4e574b7SAdam Litke 1775e4e574b7SAdam Litke /* 1776e4e574b7SAdam Litke * When releasing a hugetlb pool reservation, any surplus pages that were 1777e4e574b7SAdam Litke * allocated to satisfy the reservation must be explicitly freed if they were 1778e4e574b7SAdam Litke * never used. 1779685f3457SLee Schermerhorn * Called with hugetlb_lock held. 1780e4e574b7SAdam Litke */ 1781a5516438SAndi Kleen static void return_unused_surplus_pages(struct hstate *h, 1782a5516438SAndi Kleen unsigned long unused_resv_pages) 1783e4e574b7SAdam Litke { 1784e4e574b7SAdam Litke unsigned long nr_pages; 1785e4e574b7SAdam Litke 1786ac09b3a1SAdam Litke /* Uncommit the reservation */ 1787a5516438SAndi Kleen h->resv_huge_pages -= unused_resv_pages; 1788ac09b3a1SAdam Litke 1789aa888a74SAndi Kleen /* Cannot return gigantic pages currently */ 1790bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 1791aa888a74SAndi Kleen return; 1792aa888a74SAndi Kleen 1793a5516438SAndi Kleen nr_pages = min(unused_resv_pages, h->surplus_huge_pages); 1794e4e574b7SAdam Litke 1795685f3457SLee Schermerhorn /* 1796685f3457SLee Schermerhorn * We want to release as many surplus pages as possible, spread 17979b5e5d0fSLee Schermerhorn * evenly across all nodes with memory. Iterate across these nodes 17989b5e5d0fSLee Schermerhorn * until we can no longer free unreserved surplus pages. This occurs 17999b5e5d0fSLee Schermerhorn * when the nodes with surplus pages have no free pages. 18009b5e5d0fSLee Schermerhorn * free_pool_huge_page() will balance the the freed pages across the 18019b5e5d0fSLee Schermerhorn * on-line nodes with memory and will handle the hstate accounting. 1802685f3457SLee Schermerhorn */ 1803685f3457SLee Schermerhorn while (nr_pages--) { 18048cebfcd0SLai Jiangshan if (!free_pool_huge_page(h, &node_states[N_MEMORY], 1)) 1805685f3457SLee Schermerhorn break; 18067848a4bfSMizuma, Masayoshi cond_resched_lock(&hugetlb_lock); 1807e4e574b7SAdam Litke } 1808e4e574b7SAdam Litke } 1809e4e574b7SAdam Litke 18105e911373SMike Kravetz 1811c37f9fb1SAndy Whitcroft /* 1812feba16e2SMike Kravetz * vma_needs_reservation, vma_commit_reservation and vma_end_reservation 18135e911373SMike Kravetz * are used by the huge page allocation routines to manage reservations. 1814cf3ad20bSMike Kravetz * 1815cf3ad20bSMike Kravetz * vma_needs_reservation is called to determine if the huge page at addr 1816cf3ad20bSMike Kravetz * within the vma has an associated reservation. If a reservation is 1817cf3ad20bSMike Kravetz * needed, the value 1 is returned. The caller is then responsible for 1818cf3ad20bSMike Kravetz * managing the global reservation and subpool usage counts. After 1819cf3ad20bSMike Kravetz * the huge page has been allocated, vma_commit_reservation is called 1820feba16e2SMike Kravetz * to add the page to the reservation map. If the page allocation fails, 1821feba16e2SMike Kravetz * the reservation must be ended instead of committed. vma_end_reservation 1822feba16e2SMike Kravetz * is called in such cases. 1823cf3ad20bSMike Kravetz * 1824cf3ad20bSMike Kravetz * In the normal case, vma_commit_reservation returns the same value 1825cf3ad20bSMike Kravetz * as the preceding vma_needs_reservation call. The only time this 1826cf3ad20bSMike Kravetz * is not the case is if a reserve map was changed between calls. It 1827cf3ad20bSMike Kravetz * is the responsibility of the caller to notice the difference and 1828cf3ad20bSMike Kravetz * take appropriate action. 182996b96a96SMike Kravetz * 183096b96a96SMike Kravetz * vma_add_reservation is used in error paths where a reservation must 183196b96a96SMike Kravetz * be restored when a newly allocated huge page must be freed. It is 183296b96a96SMike Kravetz * to be called after calling vma_needs_reservation to determine if a 183396b96a96SMike Kravetz * reservation exists. 1834c37f9fb1SAndy Whitcroft */ 18355e911373SMike Kravetz enum vma_resv_mode { 18365e911373SMike Kravetz VMA_NEEDS_RESV, 18375e911373SMike Kravetz VMA_COMMIT_RESV, 1838feba16e2SMike Kravetz VMA_END_RESV, 183996b96a96SMike Kravetz VMA_ADD_RESV, 18405e911373SMike Kravetz }; 1841cf3ad20bSMike Kravetz static long __vma_reservation_common(struct hstate *h, 1842cf3ad20bSMike Kravetz struct vm_area_struct *vma, unsigned long addr, 18435e911373SMike Kravetz enum vma_resv_mode mode) 1844c37f9fb1SAndy Whitcroft { 18454e35f483SJoonsoo Kim struct resv_map *resv; 18464e35f483SJoonsoo Kim pgoff_t idx; 1847cf3ad20bSMike Kravetz long ret; 1848c37f9fb1SAndy Whitcroft 18494e35f483SJoonsoo Kim resv = vma_resv_map(vma); 18504e35f483SJoonsoo Kim if (!resv) 1851c37f9fb1SAndy Whitcroft return 1; 1852c37f9fb1SAndy Whitcroft 18534e35f483SJoonsoo Kim idx = vma_hugecache_offset(h, vma, addr); 18545e911373SMike Kravetz switch (mode) { 18555e911373SMike Kravetz case VMA_NEEDS_RESV: 1856cf3ad20bSMike Kravetz ret = region_chg(resv, idx, idx + 1); 18575e911373SMike Kravetz break; 18585e911373SMike Kravetz case VMA_COMMIT_RESV: 18595e911373SMike Kravetz ret = region_add(resv, idx, idx + 1); 18605e911373SMike Kravetz break; 1861feba16e2SMike Kravetz case VMA_END_RESV: 18625e911373SMike Kravetz region_abort(resv, idx, idx + 1); 18635e911373SMike Kravetz ret = 0; 18645e911373SMike Kravetz break; 186596b96a96SMike Kravetz case VMA_ADD_RESV: 186696b96a96SMike Kravetz if (vma->vm_flags & VM_MAYSHARE) 186796b96a96SMike Kravetz ret = region_add(resv, idx, idx + 1); 186896b96a96SMike Kravetz else { 186996b96a96SMike Kravetz region_abort(resv, idx, idx + 1); 187096b96a96SMike Kravetz ret = region_del(resv, idx, idx + 1); 187196b96a96SMike Kravetz } 187296b96a96SMike Kravetz break; 18735e911373SMike Kravetz default: 18745e911373SMike Kravetz BUG(); 18755e911373SMike Kravetz } 187684afd99bSAndy Whitcroft 18774e35f483SJoonsoo Kim if (vma->vm_flags & VM_MAYSHARE) 1878cf3ad20bSMike Kravetz return ret; 187967961f9dSMike Kravetz else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) && ret >= 0) { 188067961f9dSMike Kravetz /* 188167961f9dSMike Kravetz * In most cases, reserves always exist for private mappings. 188267961f9dSMike Kravetz * However, a file associated with mapping could have been 188367961f9dSMike Kravetz * hole punched or truncated after reserves were consumed. 188467961f9dSMike Kravetz * As subsequent fault on such a range will not use reserves. 188567961f9dSMike Kravetz * Subtle - The reserve map for private mappings has the 188667961f9dSMike Kravetz * opposite meaning than that of shared mappings. If NO 188767961f9dSMike Kravetz * entry is in the reserve map, it means a reservation exists. 188867961f9dSMike Kravetz * If an entry exists in the reserve map, it means the 188967961f9dSMike Kravetz * reservation has already been consumed. As a result, the 189067961f9dSMike Kravetz * return value of this routine is the opposite of the 189167961f9dSMike Kravetz * value returned from reserve map manipulation routines above. 189267961f9dSMike Kravetz */ 189367961f9dSMike Kravetz if (ret) 189467961f9dSMike Kravetz return 0; 189567961f9dSMike Kravetz else 189667961f9dSMike Kravetz return 1; 189767961f9dSMike Kravetz } 18984e35f483SJoonsoo Kim else 1899cf3ad20bSMike Kravetz return ret < 0 ? ret : 0; 190084afd99bSAndy Whitcroft } 1901cf3ad20bSMike Kravetz 1902cf3ad20bSMike Kravetz static long vma_needs_reservation(struct hstate *h, 1903a5516438SAndi Kleen struct vm_area_struct *vma, unsigned long addr) 1904c37f9fb1SAndy Whitcroft { 19055e911373SMike Kravetz return __vma_reservation_common(h, vma, addr, VMA_NEEDS_RESV); 1906cf3ad20bSMike Kravetz } 1907c37f9fb1SAndy Whitcroft 1908cf3ad20bSMike Kravetz static long vma_commit_reservation(struct hstate *h, 1909cf3ad20bSMike Kravetz struct vm_area_struct *vma, unsigned long addr) 1910cf3ad20bSMike Kravetz { 19115e911373SMike Kravetz return __vma_reservation_common(h, vma, addr, VMA_COMMIT_RESV); 19125e911373SMike Kravetz } 19135e911373SMike Kravetz 1914feba16e2SMike Kravetz static void vma_end_reservation(struct hstate *h, 19155e911373SMike Kravetz struct vm_area_struct *vma, unsigned long addr) 19165e911373SMike Kravetz { 1917feba16e2SMike Kravetz (void)__vma_reservation_common(h, vma, addr, VMA_END_RESV); 1918c37f9fb1SAndy Whitcroft } 1919c37f9fb1SAndy Whitcroft 192096b96a96SMike Kravetz static long vma_add_reservation(struct hstate *h, 192196b96a96SMike Kravetz struct vm_area_struct *vma, unsigned long addr) 192296b96a96SMike Kravetz { 192396b96a96SMike Kravetz return __vma_reservation_common(h, vma, addr, VMA_ADD_RESV); 192496b96a96SMike Kravetz } 192596b96a96SMike Kravetz 192696b96a96SMike Kravetz /* 192796b96a96SMike Kravetz * This routine is called to restore a reservation on error paths. In the 192896b96a96SMike Kravetz * specific error paths, a huge page was allocated (via alloc_huge_page) 192996b96a96SMike Kravetz * and is about to be freed. If a reservation for the page existed, 193096b96a96SMike Kravetz * alloc_huge_page would have consumed the reservation and set PagePrivate 193196b96a96SMike Kravetz * in the newly allocated page. When the page is freed via free_huge_page, 193296b96a96SMike Kravetz * the global reservation count will be incremented if PagePrivate is set. 193396b96a96SMike Kravetz * However, free_huge_page can not adjust the reserve map. Adjust the 193496b96a96SMike Kravetz * reserve map here to be consistent with global reserve count adjustments 193596b96a96SMike Kravetz * to be made by free_huge_page. 193696b96a96SMike Kravetz */ 193796b96a96SMike Kravetz static void restore_reserve_on_error(struct hstate *h, 193896b96a96SMike Kravetz struct vm_area_struct *vma, unsigned long address, 193996b96a96SMike Kravetz struct page *page) 194096b96a96SMike Kravetz { 194196b96a96SMike Kravetz if (unlikely(PagePrivate(page))) { 194296b96a96SMike Kravetz long rc = vma_needs_reservation(h, vma, address); 194396b96a96SMike Kravetz 194496b96a96SMike Kravetz if (unlikely(rc < 0)) { 194596b96a96SMike Kravetz /* 194696b96a96SMike Kravetz * Rare out of memory condition in reserve map 194796b96a96SMike Kravetz * manipulation. Clear PagePrivate so that 194896b96a96SMike Kravetz * global reserve count will not be incremented 194996b96a96SMike Kravetz * by free_huge_page. This will make it appear 195096b96a96SMike Kravetz * as though the reservation for this page was 195196b96a96SMike Kravetz * consumed. This may prevent the task from 195296b96a96SMike Kravetz * faulting in the page at a later time. This 195396b96a96SMike Kravetz * is better than inconsistent global huge page 195496b96a96SMike Kravetz * accounting of reserve counts. 195596b96a96SMike Kravetz */ 195696b96a96SMike Kravetz ClearPagePrivate(page); 195796b96a96SMike Kravetz } else if (rc) { 195896b96a96SMike Kravetz rc = vma_add_reservation(h, vma, address); 195996b96a96SMike Kravetz if (unlikely(rc < 0)) 196096b96a96SMike Kravetz /* 196196b96a96SMike Kravetz * See above comment about rare out of 196296b96a96SMike Kravetz * memory condition. 196396b96a96SMike Kravetz */ 196496b96a96SMike Kravetz ClearPagePrivate(page); 196596b96a96SMike Kravetz } else 196696b96a96SMike Kravetz vma_end_reservation(h, vma, address); 196796b96a96SMike Kravetz } 196896b96a96SMike Kravetz } 196996b96a96SMike Kravetz 197070c3547eSMike Kravetz struct page *alloc_huge_page(struct vm_area_struct *vma, 197104f2cbe3SMel Gorman unsigned long addr, int avoid_reserve) 1972348ea204SAdam Litke { 197390481622SDavid Gibson struct hugepage_subpool *spool = subpool_vma(vma); 1974a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 1975348ea204SAdam Litke struct page *page; 1976d85f69b0SMike Kravetz long map_chg, map_commit; 1977d85f69b0SMike Kravetz long gbl_chg; 19786d76dcf4SAneesh Kumar K.V int ret, idx; 19796d76dcf4SAneesh Kumar K.V struct hugetlb_cgroup *h_cg; 19802fc39cecSAdam Litke 19816d76dcf4SAneesh Kumar K.V idx = hstate_index(h); 1982a1e78772SMel Gorman /* 1983d85f69b0SMike Kravetz * Examine the region/reserve map to determine if the process 1984d85f69b0SMike Kravetz * has a reservation for the page to be allocated. A return 1985d85f69b0SMike Kravetz * code of zero indicates a reservation exists (no change). 1986a1e78772SMel Gorman */ 1987d85f69b0SMike Kravetz map_chg = gbl_chg = vma_needs_reservation(h, vma, addr); 1988d85f69b0SMike Kravetz if (map_chg < 0) 198976dcee75SAneesh Kumar K.V return ERR_PTR(-ENOMEM); 1990d85f69b0SMike Kravetz 1991d85f69b0SMike Kravetz /* 1992d85f69b0SMike Kravetz * Processes that did not create the mapping will have no 1993d85f69b0SMike Kravetz * reserves as indicated by the region/reserve map. Check 1994d85f69b0SMike Kravetz * that the allocation will not exceed the subpool limit. 1995d85f69b0SMike Kravetz * Allocations for MAP_NORESERVE mappings also need to be 1996d85f69b0SMike Kravetz * checked against any subpool limit. 1997d85f69b0SMike Kravetz */ 1998d85f69b0SMike Kravetz if (map_chg || avoid_reserve) { 1999d85f69b0SMike Kravetz gbl_chg = hugepage_subpool_get_pages(spool, 1); 2000d85f69b0SMike Kravetz if (gbl_chg < 0) { 2001feba16e2SMike Kravetz vma_end_reservation(h, vma, addr); 200276dcee75SAneesh Kumar K.V return ERR_PTR(-ENOSPC); 20035e911373SMike Kravetz } 200490d8b7e6SAdam Litke 2005d85f69b0SMike Kravetz /* 2006d85f69b0SMike Kravetz * Even though there was no reservation in the region/reserve 2007d85f69b0SMike Kravetz * map, there could be reservations associated with the 2008d85f69b0SMike Kravetz * subpool that can be used. This would be indicated if the 2009d85f69b0SMike Kravetz * return value of hugepage_subpool_get_pages() is zero. 2010d85f69b0SMike Kravetz * However, if avoid_reserve is specified we still avoid even 2011d85f69b0SMike Kravetz * the subpool reservations. 2012d85f69b0SMike Kravetz */ 2013d85f69b0SMike Kravetz if (avoid_reserve) 2014d85f69b0SMike Kravetz gbl_chg = 1; 2015d85f69b0SMike Kravetz } 2016d85f69b0SMike Kravetz 20176d76dcf4SAneesh Kumar K.V ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg); 20188f34af6fSJianyu Zhan if (ret) 20198f34af6fSJianyu Zhan goto out_subpool_put; 20208f34af6fSJianyu Zhan 2021a1e78772SMel Gorman spin_lock(&hugetlb_lock); 2022d85f69b0SMike Kravetz /* 2023d85f69b0SMike Kravetz * glb_chg is passed to indicate whether or not a page must be taken 2024d85f69b0SMike Kravetz * from the global free pool (global change). gbl_chg == 0 indicates 2025d85f69b0SMike Kravetz * a reservation exists for the allocation. 2026d85f69b0SMike Kravetz */ 2027d85f69b0SMike Kravetz page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, gbl_chg); 202881a6fcaeSJoonsoo Kim if (!page) { 202994ae8ba7SAneesh Kumar K.V spin_unlock(&hugetlb_lock); 2030099730d6SDave Hansen page = __alloc_buddy_huge_page_with_mpol(h, vma, addr); 20318f34af6fSJianyu Zhan if (!page) 20328f34af6fSJianyu Zhan goto out_uncharge_cgroup; 2033a88c7695SNaoya Horiguchi if (!avoid_reserve && vma_has_reserves(vma, gbl_chg)) { 2034a88c7695SNaoya Horiguchi SetPagePrivate(page); 2035a88c7695SNaoya Horiguchi h->resv_huge_pages--; 2036a88c7695SNaoya Horiguchi } 203779dbb236SAneesh Kumar K.V spin_lock(&hugetlb_lock); 203879dbb236SAneesh Kumar K.V list_move(&page->lru, &h->hugepage_activelist); 203981a6fcaeSJoonsoo Kim /* Fall through */ 2040a1e78772SMel Gorman } 204181a6fcaeSJoonsoo Kim hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, page); 204281a6fcaeSJoonsoo Kim spin_unlock(&hugetlb_lock); 2043a1e78772SMel Gorman 204490481622SDavid Gibson set_page_private(page, (unsigned long)spool); 2045a1e78772SMel Gorman 2046d85f69b0SMike Kravetz map_commit = vma_commit_reservation(h, vma, addr); 2047d85f69b0SMike Kravetz if (unlikely(map_chg > map_commit)) { 204833039678SMike Kravetz /* 204933039678SMike Kravetz * The page was added to the reservation map between 205033039678SMike Kravetz * vma_needs_reservation and vma_commit_reservation. 205133039678SMike Kravetz * This indicates a race with hugetlb_reserve_pages. 205233039678SMike Kravetz * Adjust for the subpool count incremented above AND 205333039678SMike Kravetz * in hugetlb_reserve_pages for the same page. Also, 205433039678SMike Kravetz * the reservation count added in hugetlb_reserve_pages 205533039678SMike Kravetz * no longer applies. 205633039678SMike Kravetz */ 205733039678SMike Kravetz long rsv_adjust; 205833039678SMike Kravetz 205933039678SMike Kravetz rsv_adjust = hugepage_subpool_put_pages(spool, 1); 206033039678SMike Kravetz hugetlb_acct_memory(h, -rsv_adjust); 206133039678SMike Kravetz } 20627893d1d5SAdam Litke return page; 20638f34af6fSJianyu Zhan 20648f34af6fSJianyu Zhan out_uncharge_cgroup: 20658f34af6fSJianyu Zhan hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg); 20668f34af6fSJianyu Zhan out_subpool_put: 2067d85f69b0SMike Kravetz if (map_chg || avoid_reserve) 20688f34af6fSJianyu Zhan hugepage_subpool_put_pages(spool, 1); 2069feba16e2SMike Kravetz vma_end_reservation(h, vma, addr); 20708f34af6fSJianyu Zhan return ERR_PTR(-ENOSPC); 2071b45b5bd6SDavid Gibson } 2072b45b5bd6SDavid Gibson 207374060e4dSNaoya Horiguchi /* 207474060e4dSNaoya Horiguchi * alloc_huge_page()'s wrapper which simply returns the page if allocation 207574060e4dSNaoya Horiguchi * succeeds, otherwise NULL. This function is called from new_vma_page(), 207674060e4dSNaoya Horiguchi * where no ERR_VALUE is expected to be returned. 207774060e4dSNaoya Horiguchi */ 207874060e4dSNaoya Horiguchi struct page *alloc_huge_page_noerr(struct vm_area_struct *vma, 207974060e4dSNaoya Horiguchi unsigned long addr, int avoid_reserve) 208074060e4dSNaoya Horiguchi { 208174060e4dSNaoya Horiguchi struct page *page = alloc_huge_page(vma, addr, avoid_reserve); 208274060e4dSNaoya Horiguchi if (IS_ERR(page)) 208374060e4dSNaoya Horiguchi page = NULL; 208474060e4dSNaoya Horiguchi return page; 208574060e4dSNaoya Horiguchi } 208674060e4dSNaoya Horiguchi 208791f47662SCyrill Gorcunov int __weak alloc_bootmem_huge_page(struct hstate *h) 2088aa888a74SAndi Kleen { 2089aa888a74SAndi Kleen struct huge_bootmem_page *m; 2090b2261026SJoonsoo Kim int nr_nodes, node; 2091aa888a74SAndi Kleen 2092b2261026SJoonsoo Kim for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) { 2093aa888a74SAndi Kleen void *addr; 2094aa888a74SAndi Kleen 20958b89a116SGrygorii Strashko addr = memblock_virt_alloc_try_nid_nopanic( 20968b89a116SGrygorii Strashko huge_page_size(h), huge_page_size(h), 20978b89a116SGrygorii Strashko 0, BOOTMEM_ALLOC_ACCESSIBLE, node); 2098aa888a74SAndi Kleen if (addr) { 2099aa888a74SAndi Kleen /* 2100aa888a74SAndi Kleen * Use the beginning of the huge page to store the 2101aa888a74SAndi Kleen * huge_bootmem_page struct (until gather_bootmem 2102aa888a74SAndi Kleen * puts them into the mem_map). 2103aa888a74SAndi Kleen */ 2104aa888a74SAndi Kleen m = addr; 2105aa888a74SAndi Kleen goto found; 2106aa888a74SAndi Kleen } 2107aa888a74SAndi Kleen } 2108aa888a74SAndi Kleen return 0; 2109aa888a74SAndi Kleen 2110aa888a74SAndi Kleen found: 2111df994eadSLuiz Capitulino BUG_ON(!IS_ALIGNED(virt_to_phys(m), huge_page_size(h))); 2112aa888a74SAndi Kleen /* Put them into a private list first because mem_map is not up yet */ 2113aa888a74SAndi Kleen list_add(&m->list, &huge_boot_pages); 2114aa888a74SAndi Kleen m->hstate = h; 2115aa888a74SAndi Kleen return 1; 2116aa888a74SAndi Kleen } 2117aa888a74SAndi Kleen 2118d00181b9SKirill A. Shutemov static void __init prep_compound_huge_page(struct page *page, 2119d00181b9SKirill A. Shutemov unsigned int order) 212018229df5SAndy Whitcroft { 212118229df5SAndy Whitcroft if (unlikely(order > (MAX_ORDER - 1))) 212218229df5SAndy Whitcroft prep_compound_gigantic_page(page, order); 212318229df5SAndy Whitcroft else 212418229df5SAndy Whitcroft prep_compound_page(page, order); 212518229df5SAndy Whitcroft } 212618229df5SAndy Whitcroft 2127aa888a74SAndi Kleen /* Put bootmem huge pages into the standard lists after mem_map is up */ 2128aa888a74SAndi Kleen static void __init gather_bootmem_prealloc(void) 2129aa888a74SAndi Kleen { 2130aa888a74SAndi Kleen struct huge_bootmem_page *m; 2131aa888a74SAndi Kleen 2132aa888a74SAndi Kleen list_for_each_entry(m, &huge_boot_pages, list) { 2133aa888a74SAndi Kleen struct hstate *h = m->hstate; 2134ee8f248dSBecky Bruce struct page *page; 2135ee8f248dSBecky Bruce 2136ee8f248dSBecky Bruce #ifdef CONFIG_HIGHMEM 2137ee8f248dSBecky Bruce page = pfn_to_page(m->phys >> PAGE_SHIFT); 21388b89a116SGrygorii Strashko memblock_free_late(__pa(m), 2139ee8f248dSBecky Bruce sizeof(struct huge_bootmem_page)); 2140ee8f248dSBecky Bruce #else 2141ee8f248dSBecky Bruce page = virt_to_page(m); 2142ee8f248dSBecky Bruce #endif 2143aa888a74SAndi Kleen WARN_ON(page_count(page) != 1); 214418229df5SAndy Whitcroft prep_compound_huge_page(page, h->order); 2145ef5a22beSAndrea Arcangeli WARN_ON(PageReserved(page)); 2146aa888a74SAndi Kleen prep_new_huge_page(h, page, page_to_nid(page)); 2147b0320c7bSRafael Aquini /* 2148b0320c7bSRafael Aquini * If we had gigantic hugepages allocated at boot time, we need 2149b0320c7bSRafael Aquini * to restore the 'stolen' pages to totalram_pages in order to 2150b0320c7bSRafael Aquini * fix confusing memory reports from free(1) and another 2151b0320c7bSRafael Aquini * side-effects, like CommitLimit going negative. 2152b0320c7bSRafael Aquini */ 2153bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 21543dcc0571SJiang Liu adjust_managed_page_count(page, 1 << h->order); 2155aa888a74SAndi Kleen } 2156aa888a74SAndi Kleen } 2157aa888a74SAndi Kleen 21588faa8b07SAndi Kleen static void __init hugetlb_hstate_alloc_pages(struct hstate *h) 21591da177e4SLinus Torvalds { 21601da177e4SLinus Torvalds unsigned long i; 21611da177e4SLinus Torvalds 2162e5ff2159SAndi Kleen for (i = 0; i < h->max_huge_pages; ++i) { 2163bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) { 2164aa888a74SAndi Kleen if (!alloc_bootmem_huge_page(h)) 2165aa888a74SAndi Kleen break; 21669b5e5d0fSLee Schermerhorn } else if (!alloc_fresh_huge_page(h, 21678cebfcd0SLai Jiangshan &node_states[N_MEMORY])) 21681da177e4SLinus Torvalds break; 21691da177e4SLinus Torvalds } 21708faa8b07SAndi Kleen h->max_huge_pages = i; 2171e5ff2159SAndi Kleen } 2172e5ff2159SAndi Kleen 2173e5ff2159SAndi Kleen static void __init hugetlb_init_hstates(void) 2174e5ff2159SAndi Kleen { 2175e5ff2159SAndi Kleen struct hstate *h; 2176e5ff2159SAndi Kleen 2177e5ff2159SAndi Kleen for_each_hstate(h) { 2178641844f5SNaoya Horiguchi if (minimum_order > huge_page_order(h)) 2179641844f5SNaoya Horiguchi minimum_order = huge_page_order(h); 2180641844f5SNaoya Horiguchi 21818faa8b07SAndi Kleen /* oversize hugepages were init'ed in early boot */ 2182bae7f4aeSLuiz Capitulino if (!hstate_is_gigantic(h)) 21838faa8b07SAndi Kleen hugetlb_hstate_alloc_pages(h); 2184e5ff2159SAndi Kleen } 2185641844f5SNaoya Horiguchi VM_BUG_ON(minimum_order == UINT_MAX); 2186e5ff2159SAndi Kleen } 2187e5ff2159SAndi Kleen 21884abd32dbSAndi Kleen static char * __init memfmt(char *buf, unsigned long n) 21894abd32dbSAndi Kleen { 21904abd32dbSAndi Kleen if (n >= (1UL << 30)) 21914abd32dbSAndi Kleen sprintf(buf, "%lu GB", n >> 30); 21924abd32dbSAndi Kleen else if (n >= (1UL << 20)) 21934abd32dbSAndi Kleen sprintf(buf, "%lu MB", n >> 20); 21944abd32dbSAndi Kleen else 21954abd32dbSAndi Kleen sprintf(buf, "%lu KB", n >> 10); 21964abd32dbSAndi Kleen return buf; 21974abd32dbSAndi Kleen } 21984abd32dbSAndi Kleen 2199e5ff2159SAndi Kleen static void __init report_hugepages(void) 2200e5ff2159SAndi Kleen { 2201e5ff2159SAndi Kleen struct hstate *h; 2202e5ff2159SAndi Kleen 2203e5ff2159SAndi Kleen for_each_hstate(h) { 22044abd32dbSAndi Kleen char buf[32]; 2205ffb22af5SAndrew Morton pr_info("HugeTLB registered %s page size, pre-allocated %ld pages\n", 22064abd32dbSAndi Kleen memfmt(buf, huge_page_size(h)), 22074abd32dbSAndi Kleen h->free_huge_pages); 2208e5ff2159SAndi Kleen } 2209e5ff2159SAndi Kleen } 2210e5ff2159SAndi Kleen 22111da177e4SLinus Torvalds #ifdef CONFIG_HIGHMEM 22126ae11b27SLee Schermerhorn static void try_to_free_low(struct hstate *h, unsigned long count, 22136ae11b27SLee Schermerhorn nodemask_t *nodes_allowed) 22141da177e4SLinus Torvalds { 22154415cc8dSChristoph Lameter int i; 22164415cc8dSChristoph Lameter 2217bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 2218aa888a74SAndi Kleen return; 2219aa888a74SAndi Kleen 22206ae11b27SLee Schermerhorn for_each_node_mask(i, *nodes_allowed) { 22211da177e4SLinus Torvalds struct page *page, *next; 2222a5516438SAndi Kleen struct list_head *freel = &h->hugepage_freelists[i]; 2223a5516438SAndi Kleen list_for_each_entry_safe(page, next, freel, lru) { 2224a5516438SAndi Kleen if (count >= h->nr_huge_pages) 22256b0c880dSAdam Litke return; 22261da177e4SLinus Torvalds if (PageHighMem(page)) 22271da177e4SLinus Torvalds continue; 22281da177e4SLinus Torvalds list_del(&page->lru); 2229e5ff2159SAndi Kleen update_and_free_page(h, page); 2230a5516438SAndi Kleen h->free_huge_pages--; 2231a5516438SAndi Kleen h->free_huge_pages_node[page_to_nid(page)]--; 22321da177e4SLinus Torvalds } 22331da177e4SLinus Torvalds } 22341da177e4SLinus Torvalds } 22351da177e4SLinus Torvalds #else 22366ae11b27SLee Schermerhorn static inline void try_to_free_low(struct hstate *h, unsigned long count, 22376ae11b27SLee Schermerhorn nodemask_t *nodes_allowed) 22381da177e4SLinus Torvalds { 22391da177e4SLinus Torvalds } 22401da177e4SLinus Torvalds #endif 22411da177e4SLinus Torvalds 224220a0307cSWu Fengguang /* 224320a0307cSWu Fengguang * Increment or decrement surplus_huge_pages. Keep node-specific counters 224420a0307cSWu Fengguang * balanced by operating on them in a round-robin fashion. 224520a0307cSWu Fengguang * Returns 1 if an adjustment was made. 224620a0307cSWu Fengguang */ 22476ae11b27SLee Schermerhorn static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, 22486ae11b27SLee Schermerhorn int delta) 224920a0307cSWu Fengguang { 2250b2261026SJoonsoo Kim int nr_nodes, node; 225120a0307cSWu Fengguang 225220a0307cSWu Fengguang VM_BUG_ON(delta != -1 && delta != 1); 225320a0307cSWu Fengguang 2254e8c5c824SLee Schermerhorn if (delta < 0) { 2255b2261026SJoonsoo Kim for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { 2256b2261026SJoonsoo Kim if (h->surplus_huge_pages_node[node]) 2257b2261026SJoonsoo Kim goto found; 2258b2261026SJoonsoo Kim } 2259b2261026SJoonsoo Kim } else { 2260b2261026SJoonsoo Kim for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { 2261b2261026SJoonsoo Kim if (h->surplus_huge_pages_node[node] < 2262b2261026SJoonsoo Kim h->nr_huge_pages_node[node]) 2263b2261026SJoonsoo Kim goto found; 2264e8c5c824SLee Schermerhorn } 22659a76db09SLee Schermerhorn } 2266b2261026SJoonsoo Kim return 0; 226720a0307cSWu Fengguang 2268b2261026SJoonsoo Kim found: 226920a0307cSWu Fengguang h->surplus_huge_pages += delta; 2270b2261026SJoonsoo Kim h->surplus_huge_pages_node[node] += delta; 2271b2261026SJoonsoo Kim return 1; 227220a0307cSWu Fengguang } 227320a0307cSWu Fengguang 2274a5516438SAndi Kleen #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) 22756ae11b27SLee Schermerhorn static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count, 22766ae11b27SLee Schermerhorn nodemask_t *nodes_allowed) 22771da177e4SLinus Torvalds { 22787893d1d5SAdam Litke unsigned long min_count, ret; 22791da177e4SLinus Torvalds 2280944d9fecSLuiz Capitulino if (hstate_is_gigantic(h) && !gigantic_page_supported()) 2281aa888a74SAndi Kleen return h->max_huge_pages; 2282aa888a74SAndi Kleen 22837893d1d5SAdam Litke /* 22847893d1d5SAdam Litke * Increase the pool size 22857893d1d5SAdam Litke * First take pages out of surplus state. Then make up the 22867893d1d5SAdam Litke * remaining difference by allocating fresh huge pages. 2287d1c3fb1fSNishanth Aravamudan * 2288d15c7c09SNaoya Horiguchi * We might race with __alloc_buddy_huge_page() here and be unable 2289d1c3fb1fSNishanth Aravamudan * to convert a surplus huge page to a normal huge page. That is 2290d1c3fb1fSNishanth Aravamudan * not critical, though, it just means the overall size of the 2291d1c3fb1fSNishanth Aravamudan * pool might be one hugepage larger than it needs to be, but 2292d1c3fb1fSNishanth Aravamudan * within all the constraints specified by the sysctls. 22937893d1d5SAdam Litke */ 22941da177e4SLinus Torvalds spin_lock(&hugetlb_lock); 2295a5516438SAndi Kleen while (h->surplus_huge_pages && count > persistent_huge_pages(h)) { 22966ae11b27SLee Schermerhorn if (!adjust_pool_surplus(h, nodes_allowed, -1)) 22977893d1d5SAdam Litke break; 22987893d1d5SAdam Litke } 22997893d1d5SAdam Litke 2300a5516438SAndi Kleen while (count > persistent_huge_pages(h)) { 23017893d1d5SAdam Litke /* 23027893d1d5SAdam Litke * If this allocation races such that we no longer need the 23037893d1d5SAdam Litke * page, free_huge_page will handle it by freeing the page 23047893d1d5SAdam Litke * and reducing the surplus. 23057893d1d5SAdam Litke */ 23067893d1d5SAdam Litke spin_unlock(&hugetlb_lock); 2307649920c6SJia He 2308649920c6SJia He /* yield cpu to avoid soft lockup */ 2309649920c6SJia He cond_resched(); 2310649920c6SJia He 2311944d9fecSLuiz Capitulino if (hstate_is_gigantic(h)) 2312944d9fecSLuiz Capitulino ret = alloc_fresh_gigantic_page(h, nodes_allowed); 2313944d9fecSLuiz Capitulino else 23146ae11b27SLee Schermerhorn ret = alloc_fresh_huge_page(h, nodes_allowed); 23157893d1d5SAdam Litke spin_lock(&hugetlb_lock); 23167893d1d5SAdam Litke if (!ret) 23177893d1d5SAdam Litke goto out; 23187893d1d5SAdam Litke 2319536240f2SMel Gorman /* Bail for signals. Probably ctrl-c from user */ 2320536240f2SMel Gorman if (signal_pending(current)) 2321536240f2SMel Gorman goto out; 23227893d1d5SAdam Litke } 23237893d1d5SAdam Litke 23247893d1d5SAdam Litke /* 23257893d1d5SAdam Litke * Decrease the pool size 23267893d1d5SAdam Litke * First return free pages to the buddy allocator (being careful 23277893d1d5SAdam Litke * to keep enough around to satisfy reservations). Then place 23287893d1d5SAdam Litke * pages into surplus state as needed so the pool will shrink 23297893d1d5SAdam Litke * to the desired size as pages become free. 2330d1c3fb1fSNishanth Aravamudan * 2331d1c3fb1fSNishanth Aravamudan * By placing pages into the surplus state independent of the 2332d1c3fb1fSNishanth Aravamudan * overcommit value, we are allowing the surplus pool size to 2333d1c3fb1fSNishanth Aravamudan * exceed overcommit. There are few sane options here. Since 2334d15c7c09SNaoya Horiguchi * __alloc_buddy_huge_page() is checking the global counter, 2335d1c3fb1fSNishanth Aravamudan * though, we'll note that we're not allowed to exceed surplus 2336d1c3fb1fSNishanth Aravamudan * and won't grow the pool anywhere else. Not until one of the 2337d1c3fb1fSNishanth Aravamudan * sysctls are changed, or the surplus pages go out of use. 23387893d1d5SAdam Litke */ 2339a5516438SAndi Kleen min_count = h->resv_huge_pages + h->nr_huge_pages - h->free_huge_pages; 23406b0c880dSAdam Litke min_count = max(count, min_count); 23416ae11b27SLee Schermerhorn try_to_free_low(h, min_count, nodes_allowed); 2342a5516438SAndi Kleen while (min_count < persistent_huge_pages(h)) { 23436ae11b27SLee Schermerhorn if (!free_pool_huge_page(h, nodes_allowed, 0)) 23441da177e4SLinus Torvalds break; 234555f67141SMizuma, Masayoshi cond_resched_lock(&hugetlb_lock); 23461da177e4SLinus Torvalds } 2347a5516438SAndi Kleen while (count < persistent_huge_pages(h)) { 23486ae11b27SLee Schermerhorn if (!adjust_pool_surplus(h, nodes_allowed, 1)) 23497893d1d5SAdam Litke break; 23507893d1d5SAdam Litke } 23517893d1d5SAdam Litke out: 2352a5516438SAndi Kleen ret = persistent_huge_pages(h); 23531da177e4SLinus Torvalds spin_unlock(&hugetlb_lock); 23547893d1d5SAdam Litke return ret; 23551da177e4SLinus Torvalds } 23561da177e4SLinus Torvalds 2357a3437870SNishanth Aravamudan #define HSTATE_ATTR_RO(_name) \ 2358a3437870SNishanth Aravamudan static struct kobj_attribute _name##_attr = __ATTR_RO(_name) 2359a3437870SNishanth Aravamudan 2360a3437870SNishanth Aravamudan #define HSTATE_ATTR(_name) \ 2361a3437870SNishanth Aravamudan static struct kobj_attribute _name##_attr = \ 2362a3437870SNishanth Aravamudan __ATTR(_name, 0644, _name##_show, _name##_store) 2363a3437870SNishanth Aravamudan 2364a3437870SNishanth Aravamudan static struct kobject *hugepages_kobj; 2365a3437870SNishanth Aravamudan static struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; 2366a3437870SNishanth Aravamudan 23679a305230SLee Schermerhorn static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp); 23689a305230SLee Schermerhorn 23699a305230SLee Schermerhorn static struct hstate *kobj_to_hstate(struct kobject *kobj, int *nidp) 2370a3437870SNishanth Aravamudan { 2371a3437870SNishanth Aravamudan int i; 23729a305230SLee Schermerhorn 2373a3437870SNishanth Aravamudan for (i = 0; i < HUGE_MAX_HSTATE; i++) 23749a305230SLee Schermerhorn if (hstate_kobjs[i] == kobj) { 23759a305230SLee Schermerhorn if (nidp) 23769a305230SLee Schermerhorn *nidp = NUMA_NO_NODE; 2377a3437870SNishanth Aravamudan return &hstates[i]; 23789a305230SLee Schermerhorn } 23799a305230SLee Schermerhorn 23809a305230SLee Schermerhorn return kobj_to_node_hstate(kobj, nidp); 2381a3437870SNishanth Aravamudan } 2382a3437870SNishanth Aravamudan 238306808b08SLee Schermerhorn static ssize_t nr_hugepages_show_common(struct kobject *kobj, 2384a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2385a3437870SNishanth Aravamudan { 23869a305230SLee Schermerhorn struct hstate *h; 23879a305230SLee Schermerhorn unsigned long nr_huge_pages; 23889a305230SLee Schermerhorn int nid; 23899a305230SLee Schermerhorn 23909a305230SLee Schermerhorn h = kobj_to_hstate(kobj, &nid); 23919a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) 23929a305230SLee Schermerhorn nr_huge_pages = h->nr_huge_pages; 23939a305230SLee Schermerhorn else 23949a305230SLee Schermerhorn nr_huge_pages = h->nr_huge_pages_node[nid]; 23959a305230SLee Schermerhorn 23969a305230SLee Schermerhorn return sprintf(buf, "%lu\n", nr_huge_pages); 2397a3437870SNishanth Aravamudan } 2398adbe8726SEric B Munson 2399238d3c13SDavid Rientjes static ssize_t __nr_hugepages_store_common(bool obey_mempolicy, 2400238d3c13SDavid Rientjes struct hstate *h, int nid, 2401238d3c13SDavid Rientjes unsigned long count, size_t len) 2402a3437870SNishanth Aravamudan { 2403a3437870SNishanth Aravamudan int err; 2404bad44b5bSDavid Rientjes NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY); 2405a3437870SNishanth Aravamudan 2406944d9fecSLuiz Capitulino if (hstate_is_gigantic(h) && !gigantic_page_supported()) { 2407adbe8726SEric B Munson err = -EINVAL; 2408adbe8726SEric B Munson goto out; 2409adbe8726SEric B Munson } 2410adbe8726SEric B Munson 24119a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) { 24129a305230SLee Schermerhorn /* 24139a305230SLee Schermerhorn * global hstate attribute 24149a305230SLee Schermerhorn */ 24159a305230SLee Schermerhorn if (!(obey_mempolicy && 24169a305230SLee Schermerhorn init_nodemask_of_mempolicy(nodes_allowed))) { 241706808b08SLee Schermerhorn NODEMASK_FREE(nodes_allowed); 24188cebfcd0SLai Jiangshan nodes_allowed = &node_states[N_MEMORY]; 241906808b08SLee Schermerhorn } 24209a305230SLee Schermerhorn } else if (nodes_allowed) { 24219a305230SLee Schermerhorn /* 24229a305230SLee Schermerhorn * per node hstate attribute: adjust count to global, 24239a305230SLee Schermerhorn * but restrict alloc/free to the specified node. 24249a305230SLee Schermerhorn */ 24259a305230SLee Schermerhorn count += h->nr_huge_pages - h->nr_huge_pages_node[nid]; 24269a305230SLee Schermerhorn init_nodemask_of_node(nodes_allowed, nid); 24279a305230SLee Schermerhorn } else 24288cebfcd0SLai Jiangshan nodes_allowed = &node_states[N_MEMORY]; 24299a305230SLee Schermerhorn 243006808b08SLee Schermerhorn h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed); 2431a3437870SNishanth Aravamudan 24328cebfcd0SLai Jiangshan if (nodes_allowed != &node_states[N_MEMORY]) 243306808b08SLee Schermerhorn NODEMASK_FREE(nodes_allowed); 243406808b08SLee Schermerhorn 243506808b08SLee Schermerhorn return len; 2436adbe8726SEric B Munson out: 2437adbe8726SEric B Munson NODEMASK_FREE(nodes_allowed); 2438adbe8726SEric B Munson return err; 243906808b08SLee Schermerhorn } 244006808b08SLee Schermerhorn 2441238d3c13SDavid Rientjes static ssize_t nr_hugepages_store_common(bool obey_mempolicy, 2442238d3c13SDavid Rientjes struct kobject *kobj, const char *buf, 2443238d3c13SDavid Rientjes size_t len) 2444238d3c13SDavid Rientjes { 2445238d3c13SDavid Rientjes struct hstate *h; 2446238d3c13SDavid Rientjes unsigned long count; 2447238d3c13SDavid Rientjes int nid; 2448238d3c13SDavid Rientjes int err; 2449238d3c13SDavid Rientjes 2450238d3c13SDavid Rientjes err = kstrtoul(buf, 10, &count); 2451238d3c13SDavid Rientjes if (err) 2452238d3c13SDavid Rientjes return err; 2453238d3c13SDavid Rientjes 2454238d3c13SDavid Rientjes h = kobj_to_hstate(kobj, &nid); 2455238d3c13SDavid Rientjes return __nr_hugepages_store_common(obey_mempolicy, h, nid, count, len); 2456238d3c13SDavid Rientjes } 2457238d3c13SDavid Rientjes 245806808b08SLee Schermerhorn static ssize_t nr_hugepages_show(struct kobject *kobj, 245906808b08SLee Schermerhorn struct kobj_attribute *attr, char *buf) 246006808b08SLee Schermerhorn { 246106808b08SLee Schermerhorn return nr_hugepages_show_common(kobj, attr, buf); 246206808b08SLee Schermerhorn } 246306808b08SLee Schermerhorn 246406808b08SLee Schermerhorn static ssize_t nr_hugepages_store(struct kobject *kobj, 246506808b08SLee Schermerhorn struct kobj_attribute *attr, const char *buf, size_t len) 246606808b08SLee Schermerhorn { 2467238d3c13SDavid Rientjes return nr_hugepages_store_common(false, kobj, buf, len); 2468a3437870SNishanth Aravamudan } 2469a3437870SNishanth Aravamudan HSTATE_ATTR(nr_hugepages); 2470a3437870SNishanth Aravamudan 247106808b08SLee Schermerhorn #ifdef CONFIG_NUMA 247206808b08SLee Schermerhorn 247306808b08SLee Schermerhorn /* 247406808b08SLee Schermerhorn * hstate attribute for optionally mempolicy-based constraint on persistent 247506808b08SLee Schermerhorn * huge page alloc/free. 247606808b08SLee Schermerhorn */ 247706808b08SLee Schermerhorn static ssize_t nr_hugepages_mempolicy_show(struct kobject *kobj, 247806808b08SLee Schermerhorn struct kobj_attribute *attr, char *buf) 247906808b08SLee Schermerhorn { 248006808b08SLee Schermerhorn return nr_hugepages_show_common(kobj, attr, buf); 248106808b08SLee Schermerhorn } 248206808b08SLee Schermerhorn 248306808b08SLee Schermerhorn static ssize_t nr_hugepages_mempolicy_store(struct kobject *kobj, 248406808b08SLee Schermerhorn struct kobj_attribute *attr, const char *buf, size_t len) 248506808b08SLee Schermerhorn { 2486238d3c13SDavid Rientjes return nr_hugepages_store_common(true, kobj, buf, len); 248706808b08SLee Schermerhorn } 248806808b08SLee Schermerhorn HSTATE_ATTR(nr_hugepages_mempolicy); 248906808b08SLee Schermerhorn #endif 249006808b08SLee Schermerhorn 249106808b08SLee Schermerhorn 2492a3437870SNishanth Aravamudan static ssize_t nr_overcommit_hugepages_show(struct kobject *kobj, 2493a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2494a3437870SNishanth Aravamudan { 24959a305230SLee Schermerhorn struct hstate *h = kobj_to_hstate(kobj, NULL); 2496a3437870SNishanth Aravamudan return sprintf(buf, "%lu\n", h->nr_overcommit_huge_pages); 2497a3437870SNishanth Aravamudan } 2498adbe8726SEric B Munson 2499a3437870SNishanth Aravamudan static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, 2500a3437870SNishanth Aravamudan struct kobj_attribute *attr, const char *buf, size_t count) 2501a3437870SNishanth Aravamudan { 2502a3437870SNishanth Aravamudan int err; 2503a3437870SNishanth Aravamudan unsigned long input; 25049a305230SLee Schermerhorn struct hstate *h = kobj_to_hstate(kobj, NULL); 2505a3437870SNishanth Aravamudan 2506bae7f4aeSLuiz Capitulino if (hstate_is_gigantic(h)) 2507adbe8726SEric B Munson return -EINVAL; 2508adbe8726SEric B Munson 25093dbb95f7SJingoo Han err = kstrtoul(buf, 10, &input); 2510a3437870SNishanth Aravamudan if (err) 251173ae31e5SEric B Munson return err; 2512a3437870SNishanth Aravamudan 2513a3437870SNishanth Aravamudan spin_lock(&hugetlb_lock); 2514a3437870SNishanth Aravamudan h->nr_overcommit_huge_pages = input; 2515a3437870SNishanth Aravamudan spin_unlock(&hugetlb_lock); 2516a3437870SNishanth Aravamudan 2517a3437870SNishanth Aravamudan return count; 2518a3437870SNishanth Aravamudan } 2519a3437870SNishanth Aravamudan HSTATE_ATTR(nr_overcommit_hugepages); 2520a3437870SNishanth Aravamudan 2521a3437870SNishanth Aravamudan static ssize_t free_hugepages_show(struct kobject *kobj, 2522a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2523a3437870SNishanth Aravamudan { 25249a305230SLee Schermerhorn struct hstate *h; 25259a305230SLee Schermerhorn unsigned long free_huge_pages; 25269a305230SLee Schermerhorn int nid; 25279a305230SLee Schermerhorn 25289a305230SLee Schermerhorn h = kobj_to_hstate(kobj, &nid); 25299a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) 25309a305230SLee Schermerhorn free_huge_pages = h->free_huge_pages; 25319a305230SLee Schermerhorn else 25329a305230SLee Schermerhorn free_huge_pages = h->free_huge_pages_node[nid]; 25339a305230SLee Schermerhorn 25349a305230SLee Schermerhorn return sprintf(buf, "%lu\n", free_huge_pages); 2535a3437870SNishanth Aravamudan } 2536a3437870SNishanth Aravamudan HSTATE_ATTR_RO(free_hugepages); 2537a3437870SNishanth Aravamudan 2538a3437870SNishanth Aravamudan static ssize_t resv_hugepages_show(struct kobject *kobj, 2539a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2540a3437870SNishanth Aravamudan { 25419a305230SLee Schermerhorn struct hstate *h = kobj_to_hstate(kobj, NULL); 2542a3437870SNishanth Aravamudan return sprintf(buf, "%lu\n", h->resv_huge_pages); 2543a3437870SNishanth Aravamudan } 2544a3437870SNishanth Aravamudan HSTATE_ATTR_RO(resv_hugepages); 2545a3437870SNishanth Aravamudan 2546a3437870SNishanth Aravamudan static ssize_t surplus_hugepages_show(struct kobject *kobj, 2547a3437870SNishanth Aravamudan struct kobj_attribute *attr, char *buf) 2548a3437870SNishanth Aravamudan { 25499a305230SLee Schermerhorn struct hstate *h; 25509a305230SLee Schermerhorn unsigned long surplus_huge_pages; 25519a305230SLee Schermerhorn int nid; 25529a305230SLee Schermerhorn 25539a305230SLee Schermerhorn h = kobj_to_hstate(kobj, &nid); 25549a305230SLee Schermerhorn if (nid == NUMA_NO_NODE) 25559a305230SLee Schermerhorn surplus_huge_pages = h->surplus_huge_pages; 25569a305230SLee Schermerhorn else 25579a305230SLee Schermerhorn surplus_huge_pages = h->surplus_huge_pages_node[nid]; 25589a305230SLee Schermerhorn 25599a305230SLee Schermerhorn return sprintf(buf, "%lu\n", surplus_huge_pages); 2560a3437870SNishanth Aravamudan } 2561a3437870SNishanth Aravamudan HSTATE_ATTR_RO(surplus_hugepages); 2562a3437870SNishanth Aravamudan 2563a3437870SNishanth Aravamudan static struct attribute *hstate_attrs[] = { 2564a3437870SNishanth Aravamudan &nr_hugepages_attr.attr, 2565a3437870SNishanth Aravamudan &nr_overcommit_hugepages_attr.attr, 2566a3437870SNishanth Aravamudan &free_hugepages_attr.attr, 2567a3437870SNishanth Aravamudan &resv_hugepages_attr.attr, 2568a3437870SNishanth Aravamudan &surplus_hugepages_attr.attr, 256906808b08SLee Schermerhorn #ifdef CONFIG_NUMA 257006808b08SLee Schermerhorn &nr_hugepages_mempolicy_attr.attr, 257106808b08SLee Schermerhorn #endif 2572a3437870SNishanth Aravamudan NULL, 2573a3437870SNishanth Aravamudan }; 2574a3437870SNishanth Aravamudan 2575a3437870SNishanth Aravamudan static struct attribute_group hstate_attr_group = { 2576a3437870SNishanth Aravamudan .attrs = hstate_attrs, 2577a3437870SNishanth Aravamudan }; 2578a3437870SNishanth Aravamudan 2579094e9539SJeff Mahoney static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent, 25809a305230SLee Schermerhorn struct kobject **hstate_kobjs, 25819a305230SLee Schermerhorn struct attribute_group *hstate_attr_group) 2582a3437870SNishanth Aravamudan { 2583a3437870SNishanth Aravamudan int retval; 2584972dc4deSAneesh Kumar K.V int hi = hstate_index(h); 2585a3437870SNishanth Aravamudan 25869a305230SLee Schermerhorn hstate_kobjs[hi] = kobject_create_and_add(h->name, parent); 25879a305230SLee Schermerhorn if (!hstate_kobjs[hi]) 2588a3437870SNishanth Aravamudan return -ENOMEM; 2589a3437870SNishanth Aravamudan 25909a305230SLee Schermerhorn retval = sysfs_create_group(hstate_kobjs[hi], hstate_attr_group); 2591a3437870SNishanth Aravamudan if (retval) 25929a305230SLee Schermerhorn kobject_put(hstate_kobjs[hi]); 2593a3437870SNishanth Aravamudan 2594a3437870SNishanth Aravamudan return retval; 2595a3437870SNishanth Aravamudan } 2596a3437870SNishanth Aravamudan 2597a3437870SNishanth Aravamudan static void __init hugetlb_sysfs_init(void) 2598a3437870SNishanth Aravamudan { 2599a3437870SNishanth Aravamudan struct hstate *h; 2600a3437870SNishanth Aravamudan int err; 2601a3437870SNishanth Aravamudan 2602a3437870SNishanth Aravamudan hugepages_kobj = kobject_create_and_add("hugepages", mm_kobj); 2603a3437870SNishanth Aravamudan if (!hugepages_kobj) 2604a3437870SNishanth Aravamudan return; 2605a3437870SNishanth Aravamudan 2606a3437870SNishanth Aravamudan for_each_hstate(h) { 26079a305230SLee Schermerhorn err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, 26089a305230SLee Schermerhorn hstate_kobjs, &hstate_attr_group); 2609a3437870SNishanth Aravamudan if (err) 2610ffb22af5SAndrew Morton pr_err("Hugetlb: Unable to add hstate %s", h->name); 2611a3437870SNishanth Aravamudan } 2612a3437870SNishanth Aravamudan } 2613a3437870SNishanth Aravamudan 26149a305230SLee Schermerhorn #ifdef CONFIG_NUMA 26159a305230SLee Schermerhorn 26169a305230SLee Schermerhorn /* 26179a305230SLee Schermerhorn * node_hstate/s - associate per node hstate attributes, via their kobjects, 261810fbcf4cSKay Sievers * with node devices in node_devices[] using a parallel array. The array 261910fbcf4cSKay Sievers * index of a node device or _hstate == node id. 262010fbcf4cSKay Sievers * This is here to avoid any static dependency of the node device driver, in 26219a305230SLee Schermerhorn * the base kernel, on the hugetlb module. 26229a305230SLee Schermerhorn */ 26239a305230SLee Schermerhorn struct node_hstate { 26249a305230SLee Schermerhorn struct kobject *hugepages_kobj; 26259a305230SLee Schermerhorn struct kobject *hstate_kobjs[HUGE_MAX_HSTATE]; 26269a305230SLee Schermerhorn }; 2627b4e289a6SAlexander Kuleshov static struct node_hstate node_hstates[MAX_NUMNODES]; 26289a305230SLee Schermerhorn 26299a305230SLee Schermerhorn /* 263010fbcf4cSKay Sievers * A subset of global hstate attributes for node devices 26319a305230SLee Schermerhorn */ 26329a305230SLee Schermerhorn static struct attribute *per_node_hstate_attrs[] = { 26339a305230SLee Schermerhorn &nr_hugepages_attr.attr, 26349a305230SLee Schermerhorn &free_hugepages_attr.attr, 26359a305230SLee Schermerhorn &surplus_hugepages_attr.attr, 26369a305230SLee Schermerhorn NULL, 26379a305230SLee Schermerhorn }; 26389a305230SLee Schermerhorn 26399a305230SLee Schermerhorn static struct attribute_group per_node_hstate_attr_group = { 26409a305230SLee Schermerhorn .attrs = per_node_hstate_attrs, 26419a305230SLee Schermerhorn }; 26429a305230SLee Schermerhorn 26439a305230SLee Schermerhorn /* 264410fbcf4cSKay Sievers * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj. 26459a305230SLee Schermerhorn * Returns node id via non-NULL nidp. 26469a305230SLee Schermerhorn */ 26479a305230SLee Schermerhorn static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) 26489a305230SLee Schermerhorn { 26499a305230SLee Schermerhorn int nid; 26509a305230SLee Schermerhorn 26519a305230SLee Schermerhorn for (nid = 0; nid < nr_node_ids; nid++) { 26529a305230SLee Schermerhorn struct node_hstate *nhs = &node_hstates[nid]; 26539a305230SLee Schermerhorn int i; 26549a305230SLee Schermerhorn for (i = 0; i < HUGE_MAX_HSTATE; i++) 26559a305230SLee Schermerhorn if (nhs->hstate_kobjs[i] == kobj) { 26569a305230SLee Schermerhorn if (nidp) 26579a305230SLee Schermerhorn *nidp = nid; 26589a305230SLee Schermerhorn return &hstates[i]; 26599a305230SLee Schermerhorn } 26609a305230SLee Schermerhorn } 26619a305230SLee Schermerhorn 26629a305230SLee Schermerhorn BUG(); 26639a305230SLee Schermerhorn return NULL; 26649a305230SLee Schermerhorn } 26659a305230SLee Schermerhorn 26669a305230SLee Schermerhorn /* 266710fbcf4cSKay Sievers * Unregister hstate attributes from a single node device. 26689a305230SLee Schermerhorn * No-op if no hstate attributes attached. 26699a305230SLee Schermerhorn */ 26703cd8b44fSClaudiu Ghioc static void hugetlb_unregister_node(struct node *node) 26719a305230SLee Schermerhorn { 26729a305230SLee Schermerhorn struct hstate *h; 267310fbcf4cSKay Sievers struct node_hstate *nhs = &node_hstates[node->dev.id]; 26749a305230SLee Schermerhorn 26759a305230SLee Schermerhorn if (!nhs->hugepages_kobj) 26769b5e5d0fSLee Schermerhorn return; /* no hstate attributes */ 26779a305230SLee Schermerhorn 2678972dc4deSAneesh Kumar K.V for_each_hstate(h) { 2679972dc4deSAneesh Kumar K.V int idx = hstate_index(h); 2680972dc4deSAneesh Kumar K.V if (nhs->hstate_kobjs[idx]) { 2681972dc4deSAneesh Kumar K.V kobject_put(nhs->hstate_kobjs[idx]); 2682972dc4deSAneesh Kumar K.V nhs->hstate_kobjs[idx] = NULL; 2683972dc4deSAneesh Kumar K.V } 26849a305230SLee Schermerhorn } 26859a305230SLee Schermerhorn 26869a305230SLee Schermerhorn kobject_put(nhs->hugepages_kobj); 26879a305230SLee Schermerhorn nhs->hugepages_kobj = NULL; 26889a305230SLee Schermerhorn } 26899a305230SLee Schermerhorn 26909a305230SLee Schermerhorn 26919a305230SLee Schermerhorn /* 269210fbcf4cSKay Sievers * Register hstate attributes for a single node device. 26939a305230SLee Schermerhorn * No-op if attributes already registered. 26949a305230SLee Schermerhorn */ 26953cd8b44fSClaudiu Ghioc static void hugetlb_register_node(struct node *node) 26969a305230SLee Schermerhorn { 26979a305230SLee Schermerhorn struct hstate *h; 269810fbcf4cSKay Sievers struct node_hstate *nhs = &node_hstates[node->dev.id]; 26999a305230SLee Schermerhorn int err; 27009a305230SLee Schermerhorn 27019a305230SLee Schermerhorn if (nhs->hugepages_kobj) 27029a305230SLee Schermerhorn return; /* already allocated */ 27039a305230SLee Schermerhorn 27049a305230SLee Schermerhorn nhs->hugepages_kobj = kobject_create_and_add("hugepages", 270510fbcf4cSKay Sievers &node->dev.kobj); 27069a305230SLee Schermerhorn if (!nhs->hugepages_kobj) 27079a305230SLee Schermerhorn return; 27089a305230SLee Schermerhorn 27099a305230SLee Schermerhorn for_each_hstate(h) { 27109a305230SLee Schermerhorn err = hugetlb_sysfs_add_hstate(h, nhs->hugepages_kobj, 27119a305230SLee Schermerhorn nhs->hstate_kobjs, 27129a305230SLee Schermerhorn &per_node_hstate_attr_group); 27139a305230SLee Schermerhorn if (err) { 2714ffb22af5SAndrew Morton pr_err("Hugetlb: Unable to add hstate %s for node %d\n", 271510fbcf4cSKay Sievers h->name, node->dev.id); 27169a305230SLee Schermerhorn hugetlb_unregister_node(node); 27179a305230SLee Schermerhorn break; 27189a305230SLee Schermerhorn } 27199a305230SLee Schermerhorn } 27209a305230SLee Schermerhorn } 27219a305230SLee Schermerhorn 27229a305230SLee Schermerhorn /* 27239b5e5d0fSLee Schermerhorn * hugetlb init time: register hstate attributes for all registered node 272410fbcf4cSKay Sievers * devices of nodes that have memory. All on-line nodes should have 272510fbcf4cSKay Sievers * registered their associated device by this time. 27269a305230SLee Schermerhorn */ 27277d9ca000SLuiz Capitulino static void __init hugetlb_register_all_nodes(void) 27289a305230SLee Schermerhorn { 27299a305230SLee Schermerhorn int nid; 27309a305230SLee Schermerhorn 27318cebfcd0SLai Jiangshan for_each_node_state(nid, N_MEMORY) { 27328732794bSWen Congyang struct node *node = node_devices[nid]; 273310fbcf4cSKay Sievers if (node->dev.id == nid) 27349a305230SLee Schermerhorn hugetlb_register_node(node); 27359a305230SLee Schermerhorn } 27369a305230SLee Schermerhorn 27379a305230SLee Schermerhorn /* 273810fbcf4cSKay Sievers * Let the node device driver know we're here so it can 27399a305230SLee Schermerhorn * [un]register hstate attributes on node hotplug. 27409a305230SLee Schermerhorn */ 27419a305230SLee Schermerhorn register_hugetlbfs_with_node(hugetlb_register_node, 27429a305230SLee Schermerhorn hugetlb_unregister_node); 27439a305230SLee Schermerhorn } 27449a305230SLee Schermerhorn #else /* !CONFIG_NUMA */ 27459a305230SLee Schermerhorn 27469a305230SLee Schermerhorn static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) 27479a305230SLee Schermerhorn { 27489a305230SLee Schermerhorn BUG(); 27499a305230SLee Schermerhorn if (nidp) 27509a305230SLee Schermerhorn *nidp = -1; 27519a305230SLee Schermerhorn return NULL; 27529a305230SLee Schermerhorn } 27539a305230SLee Schermerhorn 27549a305230SLee Schermerhorn static void hugetlb_register_all_nodes(void) { } 27559a305230SLee Schermerhorn 27569a305230SLee Schermerhorn #endif 27579a305230SLee Schermerhorn 2758a3437870SNishanth Aravamudan static int __init hugetlb_init(void) 2759a3437870SNishanth Aravamudan { 27608382d914SDavidlohr Bueso int i; 27618382d914SDavidlohr Bueso 2762457c1b27SNishanth Aravamudan if (!hugepages_supported()) 27630ef89d25SBenjamin Herrenschmidt return 0; 2764a3437870SNishanth Aravamudan 2765e11bfbfcSNick Piggin if (!size_to_hstate(default_hstate_size)) { 2766e11bfbfcSNick Piggin default_hstate_size = HPAGE_SIZE; 2767e11bfbfcSNick Piggin if (!size_to_hstate(default_hstate_size)) 2768a3437870SNishanth Aravamudan hugetlb_add_hstate(HUGETLB_PAGE_ORDER); 2769a3437870SNishanth Aravamudan } 2770972dc4deSAneesh Kumar K.V default_hstate_idx = hstate_index(size_to_hstate(default_hstate_size)); 2771f8b74815SVaishali Thakkar if (default_hstate_max_huge_pages) { 2772f8b74815SVaishali Thakkar if (!default_hstate.max_huge_pages) 2773e11bfbfcSNick Piggin default_hstate.max_huge_pages = default_hstate_max_huge_pages; 2774f8b74815SVaishali Thakkar } 2775a3437870SNishanth Aravamudan 2776a3437870SNishanth Aravamudan hugetlb_init_hstates(); 2777aa888a74SAndi Kleen gather_bootmem_prealloc(); 2778a3437870SNishanth Aravamudan report_hugepages(); 2779a3437870SNishanth Aravamudan 2780a3437870SNishanth Aravamudan hugetlb_sysfs_init(); 27819a305230SLee Schermerhorn hugetlb_register_all_nodes(); 27827179e7bfSJianguo Wu hugetlb_cgroup_file_init(); 27839a305230SLee Schermerhorn 27848382d914SDavidlohr Bueso #ifdef CONFIG_SMP 27858382d914SDavidlohr Bueso num_fault_mutexes = roundup_pow_of_two(8 * num_possible_cpus()); 27868382d914SDavidlohr Bueso #else 27878382d914SDavidlohr Bueso num_fault_mutexes = 1; 27888382d914SDavidlohr Bueso #endif 2789c672c7f2SMike Kravetz hugetlb_fault_mutex_table = 27908382d914SDavidlohr Bueso kmalloc(sizeof(struct mutex) * num_fault_mutexes, GFP_KERNEL); 2791c672c7f2SMike Kravetz BUG_ON(!hugetlb_fault_mutex_table); 27928382d914SDavidlohr Bueso 27938382d914SDavidlohr Bueso for (i = 0; i < num_fault_mutexes; i++) 2794c672c7f2SMike Kravetz mutex_init(&hugetlb_fault_mutex_table[i]); 2795a3437870SNishanth Aravamudan return 0; 2796a3437870SNishanth Aravamudan } 27973e89e1c5SPaul Gortmaker subsys_initcall(hugetlb_init); 2798a3437870SNishanth Aravamudan 2799a3437870SNishanth Aravamudan /* Should be called on processing a hugepagesz=... option */ 28009fee021dSVaishali Thakkar void __init hugetlb_bad_size(void) 28019fee021dSVaishali Thakkar { 28029fee021dSVaishali Thakkar parsed_valid_hugepagesz = false; 28039fee021dSVaishali Thakkar } 28049fee021dSVaishali Thakkar 2805d00181b9SKirill A. Shutemov void __init hugetlb_add_hstate(unsigned int order) 2806a3437870SNishanth Aravamudan { 2807a3437870SNishanth Aravamudan struct hstate *h; 28088faa8b07SAndi Kleen unsigned long i; 28098faa8b07SAndi Kleen 2810a3437870SNishanth Aravamudan if (size_to_hstate(PAGE_SIZE << order)) { 2811598d8091SJoe Perches pr_warn("hugepagesz= specified twice, ignoring\n"); 2812a3437870SNishanth Aravamudan return; 2813a3437870SNishanth Aravamudan } 281447d38344SAneesh Kumar K.V BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE); 2815a3437870SNishanth Aravamudan BUG_ON(order == 0); 281647d38344SAneesh Kumar K.V h = &hstates[hugetlb_max_hstate++]; 2817a3437870SNishanth Aravamudan h->order = order; 2818a3437870SNishanth Aravamudan h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1); 28198faa8b07SAndi Kleen h->nr_huge_pages = 0; 28208faa8b07SAndi Kleen h->free_huge_pages = 0; 28218faa8b07SAndi Kleen for (i = 0; i < MAX_NUMNODES; ++i) 28228faa8b07SAndi Kleen INIT_LIST_HEAD(&h->hugepage_freelists[i]); 28230edaecfaSAneesh Kumar K.V INIT_LIST_HEAD(&h->hugepage_activelist); 282454f18d35SAndrew Morton h->next_nid_to_alloc = first_memory_node; 282554f18d35SAndrew Morton h->next_nid_to_free = first_memory_node; 2826a3437870SNishanth Aravamudan snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB", 2827a3437870SNishanth Aravamudan huge_page_size(h)/1024); 28288faa8b07SAndi Kleen 2829a3437870SNishanth Aravamudan parsed_hstate = h; 2830a3437870SNishanth Aravamudan } 2831a3437870SNishanth Aravamudan 2832e11bfbfcSNick Piggin static int __init hugetlb_nrpages_setup(char *s) 2833a3437870SNishanth Aravamudan { 2834a3437870SNishanth Aravamudan unsigned long *mhp; 28358faa8b07SAndi Kleen static unsigned long *last_mhp; 2836a3437870SNishanth Aravamudan 28379fee021dSVaishali Thakkar if (!parsed_valid_hugepagesz) { 28389fee021dSVaishali Thakkar pr_warn("hugepages = %s preceded by " 28399fee021dSVaishali Thakkar "an unsupported hugepagesz, ignoring\n", s); 28409fee021dSVaishali Thakkar parsed_valid_hugepagesz = true; 28419fee021dSVaishali Thakkar return 1; 28429fee021dSVaishali Thakkar } 2843a3437870SNishanth Aravamudan /* 284447d38344SAneesh Kumar K.V * !hugetlb_max_hstate means we haven't parsed a hugepagesz= parameter yet, 2845a3437870SNishanth Aravamudan * so this hugepages= parameter goes to the "default hstate". 2846a3437870SNishanth Aravamudan */ 28479fee021dSVaishali Thakkar else if (!hugetlb_max_hstate) 2848a3437870SNishanth Aravamudan mhp = &default_hstate_max_huge_pages; 2849a3437870SNishanth Aravamudan else 2850a3437870SNishanth Aravamudan mhp = &parsed_hstate->max_huge_pages; 2851a3437870SNishanth Aravamudan 28528faa8b07SAndi Kleen if (mhp == last_mhp) { 2853598d8091SJoe Perches pr_warn("hugepages= specified twice without interleaving hugepagesz=, ignoring\n"); 28548faa8b07SAndi Kleen return 1; 28558faa8b07SAndi Kleen } 28568faa8b07SAndi Kleen 2857a3437870SNishanth Aravamudan if (sscanf(s, "%lu", mhp) <= 0) 2858a3437870SNishanth Aravamudan *mhp = 0; 2859a3437870SNishanth Aravamudan 28608faa8b07SAndi Kleen /* 28618faa8b07SAndi Kleen * Global state is always initialized later in hugetlb_init. 28628faa8b07SAndi Kleen * But we need to allocate >= MAX_ORDER hstates here early to still 28638faa8b07SAndi Kleen * use the bootmem allocator. 28648faa8b07SAndi Kleen */ 286547d38344SAneesh Kumar K.V if (hugetlb_max_hstate && parsed_hstate->order >= MAX_ORDER) 28668faa8b07SAndi Kleen hugetlb_hstate_alloc_pages(parsed_hstate); 28678faa8b07SAndi Kleen 28688faa8b07SAndi Kleen last_mhp = mhp; 28698faa8b07SAndi Kleen 2870a3437870SNishanth Aravamudan return 1; 2871a3437870SNishanth Aravamudan } 2872e11bfbfcSNick Piggin __setup("hugepages=", hugetlb_nrpages_setup); 2873e11bfbfcSNick Piggin 2874e11bfbfcSNick Piggin static int __init hugetlb_default_setup(char *s) 2875e11bfbfcSNick Piggin { 2876e11bfbfcSNick Piggin default_hstate_size = memparse(s, &s); 2877e11bfbfcSNick Piggin return 1; 2878e11bfbfcSNick Piggin } 2879e11bfbfcSNick Piggin __setup("default_hugepagesz=", hugetlb_default_setup); 2880a3437870SNishanth Aravamudan 28818a213460SNishanth Aravamudan static unsigned int cpuset_mems_nr(unsigned int *array) 28828a213460SNishanth Aravamudan { 28838a213460SNishanth Aravamudan int node; 28848a213460SNishanth Aravamudan unsigned int nr = 0; 28858a213460SNishanth Aravamudan 28868a213460SNishanth Aravamudan for_each_node_mask(node, cpuset_current_mems_allowed) 28878a213460SNishanth Aravamudan nr += array[node]; 28888a213460SNishanth Aravamudan 28898a213460SNishanth Aravamudan return nr; 28908a213460SNishanth Aravamudan } 28918a213460SNishanth Aravamudan 28928a213460SNishanth Aravamudan #ifdef CONFIG_SYSCTL 289306808b08SLee Schermerhorn static int hugetlb_sysctl_handler_common(bool obey_mempolicy, 289406808b08SLee Schermerhorn struct ctl_table *table, int write, 289506808b08SLee Schermerhorn void __user *buffer, size_t *length, loff_t *ppos) 28961da177e4SLinus Torvalds { 2897e5ff2159SAndi Kleen struct hstate *h = &default_hstate; 2898238d3c13SDavid Rientjes unsigned long tmp = h->max_huge_pages; 289908d4a246SMichal Hocko int ret; 2900e5ff2159SAndi Kleen 2901457c1b27SNishanth Aravamudan if (!hugepages_supported()) 290286613628SJan Stancek return -EOPNOTSUPP; 2903457c1b27SNishanth Aravamudan 2904e5ff2159SAndi Kleen table->data = &tmp; 2905e5ff2159SAndi Kleen table->maxlen = sizeof(unsigned long); 290608d4a246SMichal Hocko ret = proc_doulongvec_minmax(table, write, buffer, length, ppos); 290708d4a246SMichal Hocko if (ret) 290808d4a246SMichal Hocko goto out; 2909e5ff2159SAndi Kleen 2910238d3c13SDavid Rientjes if (write) 2911238d3c13SDavid Rientjes ret = __nr_hugepages_store_common(obey_mempolicy, h, 2912238d3c13SDavid Rientjes NUMA_NO_NODE, tmp, *length); 291308d4a246SMichal Hocko out: 291408d4a246SMichal Hocko return ret; 29151da177e4SLinus Torvalds } 2916396faf03SMel Gorman 291706808b08SLee Schermerhorn int hugetlb_sysctl_handler(struct ctl_table *table, int write, 291806808b08SLee Schermerhorn void __user *buffer, size_t *length, loff_t *ppos) 291906808b08SLee Schermerhorn { 292006808b08SLee Schermerhorn 292106808b08SLee Schermerhorn return hugetlb_sysctl_handler_common(false, table, write, 292206808b08SLee Schermerhorn buffer, length, ppos); 292306808b08SLee Schermerhorn } 292406808b08SLee Schermerhorn 292506808b08SLee Schermerhorn #ifdef CONFIG_NUMA 292606808b08SLee Schermerhorn int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, 292706808b08SLee Schermerhorn void __user *buffer, size_t *length, loff_t *ppos) 292806808b08SLee Schermerhorn { 292906808b08SLee Schermerhorn return hugetlb_sysctl_handler_common(true, table, write, 293006808b08SLee Schermerhorn buffer, length, ppos); 293106808b08SLee Schermerhorn } 293206808b08SLee Schermerhorn #endif /* CONFIG_NUMA */ 293306808b08SLee Schermerhorn 2934a3d0c6aaSNishanth Aravamudan int hugetlb_overcommit_handler(struct ctl_table *table, int write, 29358d65af78SAlexey Dobriyan void __user *buffer, 2936a3d0c6aaSNishanth Aravamudan size_t *length, loff_t *ppos) 2937a3d0c6aaSNishanth Aravamudan { 2938a5516438SAndi Kleen struct hstate *h = &default_hstate; 2939e5ff2159SAndi Kleen unsigned long tmp; 294008d4a246SMichal Hocko int ret; 2941e5ff2159SAndi Kleen 2942457c1b27SNishanth Aravamudan if (!hugepages_supported()) 294386613628SJan Stancek return -EOPNOTSUPP; 2944457c1b27SNishanth Aravamudan 2945e5ff2159SAndi Kleen tmp = h->nr_overcommit_huge_pages; 2946e5ff2159SAndi Kleen 2947bae7f4aeSLuiz Capitulino if (write && hstate_is_gigantic(h)) 2948adbe8726SEric B Munson return -EINVAL; 2949adbe8726SEric B Munson 2950e5ff2159SAndi Kleen table->data = &tmp; 2951e5ff2159SAndi Kleen table->maxlen = sizeof(unsigned long); 295208d4a246SMichal Hocko ret = proc_doulongvec_minmax(table, write, buffer, length, ppos); 295308d4a246SMichal Hocko if (ret) 295408d4a246SMichal Hocko goto out; 2955e5ff2159SAndi Kleen 2956e5ff2159SAndi Kleen if (write) { 2957064d9efeSNishanth Aravamudan spin_lock(&hugetlb_lock); 2958e5ff2159SAndi Kleen h->nr_overcommit_huge_pages = tmp; 2959a3d0c6aaSNishanth Aravamudan spin_unlock(&hugetlb_lock); 2960e5ff2159SAndi Kleen } 296108d4a246SMichal Hocko out: 296208d4a246SMichal Hocko return ret; 2963a3d0c6aaSNishanth Aravamudan } 2964a3d0c6aaSNishanth Aravamudan 29651da177e4SLinus Torvalds #endif /* CONFIG_SYSCTL */ 29661da177e4SLinus Torvalds 2967e1759c21SAlexey Dobriyan void hugetlb_report_meminfo(struct seq_file *m) 29681da177e4SLinus Torvalds { 2969a5516438SAndi Kleen struct hstate *h = &default_hstate; 2970457c1b27SNishanth Aravamudan if (!hugepages_supported()) 2971457c1b27SNishanth Aravamudan return; 2972e1759c21SAlexey Dobriyan seq_printf(m, 29731da177e4SLinus Torvalds "HugePages_Total: %5lu\n" 29741da177e4SLinus Torvalds "HugePages_Free: %5lu\n" 2975b45b5bd6SDavid Gibson "HugePages_Rsvd: %5lu\n" 29767893d1d5SAdam Litke "HugePages_Surp: %5lu\n" 29774f98a2feSRik van Riel "Hugepagesize: %8lu kB\n", 2978a5516438SAndi Kleen h->nr_huge_pages, 2979a5516438SAndi Kleen h->free_huge_pages, 2980a5516438SAndi Kleen h->resv_huge_pages, 2981a5516438SAndi Kleen h->surplus_huge_pages, 2982a5516438SAndi Kleen 1UL << (huge_page_order(h) + PAGE_SHIFT - 10)); 29831da177e4SLinus Torvalds } 29841da177e4SLinus Torvalds 29851da177e4SLinus Torvalds int hugetlb_report_node_meminfo(int nid, char *buf) 29861da177e4SLinus Torvalds { 2987a5516438SAndi Kleen struct hstate *h = &default_hstate; 2988457c1b27SNishanth Aravamudan if (!hugepages_supported()) 2989457c1b27SNishanth Aravamudan return 0; 29901da177e4SLinus Torvalds return sprintf(buf, 29911da177e4SLinus Torvalds "Node %d HugePages_Total: %5u\n" 2992a1de0919SNishanth Aravamudan "Node %d HugePages_Free: %5u\n" 2993a1de0919SNishanth Aravamudan "Node %d HugePages_Surp: %5u\n", 2994a5516438SAndi Kleen nid, h->nr_huge_pages_node[nid], 2995a5516438SAndi Kleen nid, h->free_huge_pages_node[nid], 2996a5516438SAndi Kleen nid, h->surplus_huge_pages_node[nid]); 29971da177e4SLinus Torvalds } 29981da177e4SLinus Torvalds 2999949f7ec5SDavid Rientjes void hugetlb_show_meminfo(void) 3000949f7ec5SDavid Rientjes { 3001949f7ec5SDavid Rientjes struct hstate *h; 3002949f7ec5SDavid Rientjes int nid; 3003949f7ec5SDavid Rientjes 3004457c1b27SNishanth Aravamudan if (!hugepages_supported()) 3005457c1b27SNishanth Aravamudan return; 3006457c1b27SNishanth Aravamudan 3007949f7ec5SDavid Rientjes for_each_node_state(nid, N_MEMORY) 3008949f7ec5SDavid Rientjes for_each_hstate(h) 3009949f7ec5SDavid Rientjes pr_info("Node %d hugepages_total=%u hugepages_free=%u hugepages_surp=%u hugepages_size=%lukB\n", 3010949f7ec5SDavid Rientjes nid, 3011949f7ec5SDavid Rientjes h->nr_huge_pages_node[nid], 3012949f7ec5SDavid Rientjes h->free_huge_pages_node[nid], 3013949f7ec5SDavid Rientjes h->surplus_huge_pages_node[nid], 3014949f7ec5SDavid Rientjes 1UL << (huge_page_order(h) + PAGE_SHIFT - 10)); 3015949f7ec5SDavid Rientjes } 3016949f7ec5SDavid Rientjes 30175d317b2bSNaoya Horiguchi void hugetlb_report_usage(struct seq_file *m, struct mm_struct *mm) 30185d317b2bSNaoya Horiguchi { 30195d317b2bSNaoya Horiguchi seq_printf(m, "HugetlbPages:\t%8lu kB\n", 30205d317b2bSNaoya Horiguchi atomic_long_read(&mm->hugetlb_usage) << (PAGE_SHIFT - 10)); 30215d317b2bSNaoya Horiguchi } 30225d317b2bSNaoya Horiguchi 30231da177e4SLinus Torvalds /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ 30241da177e4SLinus Torvalds unsigned long hugetlb_total_pages(void) 30251da177e4SLinus Torvalds { 3026d0028588SWanpeng Li struct hstate *h; 3027d0028588SWanpeng Li unsigned long nr_total_pages = 0; 3028d0028588SWanpeng Li 3029d0028588SWanpeng Li for_each_hstate(h) 3030d0028588SWanpeng Li nr_total_pages += h->nr_huge_pages * pages_per_huge_page(h); 3031d0028588SWanpeng Li return nr_total_pages; 30321da177e4SLinus Torvalds } 30331da177e4SLinus Torvalds 3034a5516438SAndi Kleen static int hugetlb_acct_memory(struct hstate *h, long delta) 3035fc1b8a73SMel Gorman { 3036fc1b8a73SMel Gorman int ret = -ENOMEM; 3037fc1b8a73SMel Gorman 3038fc1b8a73SMel Gorman spin_lock(&hugetlb_lock); 3039fc1b8a73SMel Gorman /* 3040fc1b8a73SMel Gorman * When cpuset is configured, it breaks the strict hugetlb page 3041fc1b8a73SMel Gorman * reservation as the accounting is done on a global variable. Such 3042fc1b8a73SMel Gorman * reservation is completely rubbish in the presence of cpuset because 3043fc1b8a73SMel Gorman * the reservation is not checked against page availability for the 3044fc1b8a73SMel Gorman * current cpuset. Application can still potentially OOM'ed by kernel 3045fc1b8a73SMel Gorman * with lack of free htlb page in cpuset that the task is in. 3046fc1b8a73SMel Gorman * Attempt to enforce strict accounting with cpuset is almost 3047fc1b8a73SMel Gorman * impossible (or too ugly) because cpuset is too fluid that 3048fc1b8a73SMel Gorman * task or memory node can be dynamically moved between cpusets. 3049fc1b8a73SMel Gorman * 3050fc1b8a73SMel Gorman * The change of semantics for shared hugetlb mapping with cpuset is 3051fc1b8a73SMel Gorman * undesirable. However, in order to preserve some of the semantics, 3052fc1b8a73SMel Gorman * we fall back to check against current free page availability as 3053fc1b8a73SMel Gorman * a best attempt and hopefully to minimize the impact of changing 3054fc1b8a73SMel Gorman * semantics that cpuset has. 3055fc1b8a73SMel Gorman */ 3056fc1b8a73SMel Gorman if (delta > 0) { 3057a5516438SAndi Kleen if (gather_surplus_pages(h, delta) < 0) 3058fc1b8a73SMel Gorman goto out; 3059fc1b8a73SMel Gorman 3060a5516438SAndi Kleen if (delta > cpuset_mems_nr(h->free_huge_pages_node)) { 3061a5516438SAndi Kleen return_unused_surplus_pages(h, delta); 3062fc1b8a73SMel Gorman goto out; 3063fc1b8a73SMel Gorman } 3064fc1b8a73SMel Gorman } 3065fc1b8a73SMel Gorman 3066fc1b8a73SMel Gorman ret = 0; 3067fc1b8a73SMel Gorman if (delta < 0) 3068a5516438SAndi Kleen return_unused_surplus_pages(h, (unsigned long) -delta); 3069fc1b8a73SMel Gorman 3070fc1b8a73SMel Gorman out: 3071fc1b8a73SMel Gorman spin_unlock(&hugetlb_lock); 3072fc1b8a73SMel Gorman return ret; 3073fc1b8a73SMel Gorman } 3074fc1b8a73SMel Gorman 307584afd99bSAndy Whitcroft static void hugetlb_vm_op_open(struct vm_area_struct *vma) 307684afd99bSAndy Whitcroft { 3077f522c3acSJoonsoo Kim struct resv_map *resv = vma_resv_map(vma); 307884afd99bSAndy Whitcroft 307984afd99bSAndy Whitcroft /* 308084afd99bSAndy Whitcroft * This new VMA should share its siblings reservation map if present. 308184afd99bSAndy Whitcroft * The VMA will only ever have a valid reservation map pointer where 308284afd99bSAndy Whitcroft * it is being copied for another still existing VMA. As that VMA 308325985edcSLucas De Marchi * has a reference to the reservation map it cannot disappear until 308484afd99bSAndy Whitcroft * after this open call completes. It is therefore safe to take a 308584afd99bSAndy Whitcroft * new reference here without additional locking. 308684afd99bSAndy Whitcroft */ 30874e35f483SJoonsoo Kim if (resv && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) 3088f522c3acSJoonsoo Kim kref_get(&resv->refs); 308984afd99bSAndy Whitcroft } 309084afd99bSAndy Whitcroft 3091a1e78772SMel Gorman static void hugetlb_vm_op_close(struct vm_area_struct *vma) 3092a1e78772SMel Gorman { 3093a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 3094f522c3acSJoonsoo Kim struct resv_map *resv = vma_resv_map(vma); 309590481622SDavid Gibson struct hugepage_subpool *spool = subpool_vma(vma); 30964e35f483SJoonsoo Kim unsigned long reserve, start, end; 30971c5ecae3SMike Kravetz long gbl_reserve; 309884afd99bSAndy Whitcroft 30994e35f483SJoonsoo Kim if (!resv || !is_vma_resv_set(vma, HPAGE_RESV_OWNER)) 31004e35f483SJoonsoo Kim return; 31014e35f483SJoonsoo Kim 3102a5516438SAndi Kleen start = vma_hugecache_offset(h, vma, vma->vm_start); 3103a5516438SAndi Kleen end = vma_hugecache_offset(h, vma, vma->vm_end); 310484afd99bSAndy Whitcroft 31054e35f483SJoonsoo Kim reserve = (end - start) - region_count(resv, start, end); 310684afd99bSAndy Whitcroft 3107f031dd27SJoonsoo Kim kref_put(&resv->refs, resv_map_release); 310884afd99bSAndy Whitcroft 31097251ff78SAdam Litke if (reserve) { 31101c5ecae3SMike Kravetz /* 31111c5ecae3SMike Kravetz * Decrement reserve counts. The global reserve count may be 31121c5ecae3SMike Kravetz * adjusted if the subpool has a minimum size. 31131c5ecae3SMike Kravetz */ 31141c5ecae3SMike Kravetz gbl_reserve = hugepage_subpool_put_pages(spool, reserve); 31151c5ecae3SMike Kravetz hugetlb_acct_memory(h, -gbl_reserve); 31167251ff78SAdam Litke } 3117a1e78772SMel Gorman } 3118a1e78772SMel Gorman 31191da177e4SLinus Torvalds /* 31201da177e4SLinus Torvalds * We cannot handle pagefaults against hugetlb pages at all. They cause 31211da177e4SLinus Torvalds * handle_mm_fault() to try to instantiate regular-sized pages in the 31221da177e4SLinus Torvalds * hugegpage VMA. do_page_fault() is supposed to trap this, so BUG is we get 31231da177e4SLinus Torvalds * this far. 31241da177e4SLinus Torvalds */ 3125d0217ac0SNick Piggin static int hugetlb_vm_op_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 31261da177e4SLinus Torvalds { 31271da177e4SLinus Torvalds BUG(); 3128d0217ac0SNick Piggin return 0; 31291da177e4SLinus Torvalds } 31301da177e4SLinus Torvalds 3131f0f37e2fSAlexey Dobriyan const struct vm_operations_struct hugetlb_vm_ops = { 3132d0217ac0SNick Piggin .fault = hugetlb_vm_op_fault, 313384afd99bSAndy Whitcroft .open = hugetlb_vm_op_open, 3134a1e78772SMel Gorman .close = hugetlb_vm_op_close, 31351da177e4SLinus Torvalds }; 31361da177e4SLinus Torvalds 31371e8f889bSDavid Gibson static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, 31381e8f889bSDavid Gibson int writable) 313963551ae0SDavid Gibson { 314063551ae0SDavid Gibson pte_t entry; 314163551ae0SDavid Gibson 31421e8f889bSDavid Gibson if (writable) { 3143106c992aSGerald Schaefer entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page, 3144106c992aSGerald Schaefer vma->vm_page_prot))); 314563551ae0SDavid Gibson } else { 3146106c992aSGerald Schaefer entry = huge_pte_wrprotect(mk_huge_pte(page, 3147106c992aSGerald Schaefer vma->vm_page_prot)); 314863551ae0SDavid Gibson } 314963551ae0SDavid Gibson entry = pte_mkyoung(entry); 315063551ae0SDavid Gibson entry = pte_mkhuge(entry); 3151d9ed9faaSChris Metcalf entry = arch_make_huge_pte(entry, vma, page, writable); 315263551ae0SDavid Gibson 315363551ae0SDavid Gibson return entry; 315463551ae0SDavid Gibson } 315563551ae0SDavid Gibson 31561e8f889bSDavid Gibson static void set_huge_ptep_writable(struct vm_area_struct *vma, 31571e8f889bSDavid Gibson unsigned long address, pte_t *ptep) 31581e8f889bSDavid Gibson { 31591e8f889bSDavid Gibson pte_t entry; 31601e8f889bSDavid Gibson 3161106c992aSGerald Schaefer entry = huge_pte_mkwrite(huge_pte_mkdirty(huge_ptep_get(ptep))); 316232f84528SChris Forbes if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) 31634b3073e1SRussell King update_mmu_cache(vma, address, ptep); 31641e8f889bSDavid Gibson } 31651e8f889bSDavid Gibson 31664a705fefSNaoya Horiguchi static int is_hugetlb_entry_migration(pte_t pte) 31674a705fefSNaoya Horiguchi { 31684a705fefSNaoya Horiguchi swp_entry_t swp; 31694a705fefSNaoya Horiguchi 31704a705fefSNaoya Horiguchi if (huge_pte_none(pte) || pte_present(pte)) 31714a705fefSNaoya Horiguchi return 0; 31724a705fefSNaoya Horiguchi swp = pte_to_swp_entry(pte); 31734a705fefSNaoya Horiguchi if (non_swap_entry(swp) && is_migration_entry(swp)) 31744a705fefSNaoya Horiguchi return 1; 31754a705fefSNaoya Horiguchi else 31764a705fefSNaoya Horiguchi return 0; 31774a705fefSNaoya Horiguchi } 31784a705fefSNaoya Horiguchi 31794a705fefSNaoya Horiguchi static int is_hugetlb_entry_hwpoisoned(pte_t pte) 31804a705fefSNaoya Horiguchi { 31814a705fefSNaoya Horiguchi swp_entry_t swp; 31824a705fefSNaoya Horiguchi 31834a705fefSNaoya Horiguchi if (huge_pte_none(pte) || pte_present(pte)) 31844a705fefSNaoya Horiguchi return 0; 31854a705fefSNaoya Horiguchi swp = pte_to_swp_entry(pte); 31864a705fefSNaoya Horiguchi if (non_swap_entry(swp) && is_hwpoison_entry(swp)) 31874a705fefSNaoya Horiguchi return 1; 31884a705fefSNaoya Horiguchi else 31894a705fefSNaoya Horiguchi return 0; 31904a705fefSNaoya Horiguchi } 31911e8f889bSDavid Gibson 319263551ae0SDavid Gibson int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, 319363551ae0SDavid Gibson struct vm_area_struct *vma) 319463551ae0SDavid Gibson { 319563551ae0SDavid Gibson pte_t *src_pte, *dst_pte, entry; 319663551ae0SDavid Gibson struct page *ptepage; 31971c59827dSHugh Dickins unsigned long addr; 31981e8f889bSDavid Gibson int cow; 3199a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 3200a5516438SAndi Kleen unsigned long sz = huge_page_size(h); 3201e8569dd2SAndreas Sandberg unsigned long mmun_start; /* For mmu_notifiers */ 3202e8569dd2SAndreas Sandberg unsigned long mmun_end; /* For mmu_notifiers */ 3203e8569dd2SAndreas Sandberg int ret = 0; 32041e8f889bSDavid Gibson 32051e8f889bSDavid Gibson cow = (vma->vm_flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE; 320663551ae0SDavid Gibson 3207e8569dd2SAndreas Sandberg mmun_start = vma->vm_start; 3208e8569dd2SAndreas Sandberg mmun_end = vma->vm_end; 3209e8569dd2SAndreas Sandberg if (cow) 3210e8569dd2SAndreas Sandberg mmu_notifier_invalidate_range_start(src, mmun_start, mmun_end); 3211e8569dd2SAndreas Sandberg 3212a5516438SAndi Kleen for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) { 3213cb900f41SKirill A. Shutemov spinlock_t *src_ptl, *dst_ptl; 3214c74df32cSHugh Dickins src_pte = huge_pte_offset(src, addr); 3215c74df32cSHugh Dickins if (!src_pte) 3216c74df32cSHugh Dickins continue; 3217a5516438SAndi Kleen dst_pte = huge_pte_alloc(dst, addr, sz); 3218e8569dd2SAndreas Sandberg if (!dst_pte) { 3219e8569dd2SAndreas Sandberg ret = -ENOMEM; 3220e8569dd2SAndreas Sandberg break; 3221e8569dd2SAndreas Sandberg } 3222c5c99429SLarry Woodman 3223c5c99429SLarry Woodman /* If the pagetables are shared don't copy or take references */ 3224c5c99429SLarry Woodman if (dst_pte == src_pte) 3225c5c99429SLarry Woodman continue; 3226c5c99429SLarry Woodman 3227cb900f41SKirill A. Shutemov dst_ptl = huge_pte_lock(h, dst, dst_pte); 3228cb900f41SKirill A. Shutemov src_ptl = huge_pte_lockptr(h, src, src_pte); 3229cb900f41SKirill A. Shutemov spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); 32304a705fefSNaoya Horiguchi entry = huge_ptep_get(src_pte); 32314a705fefSNaoya Horiguchi if (huge_pte_none(entry)) { /* skip none entry */ 32324a705fefSNaoya Horiguchi ; 32334a705fefSNaoya Horiguchi } else if (unlikely(is_hugetlb_entry_migration(entry) || 32344a705fefSNaoya Horiguchi is_hugetlb_entry_hwpoisoned(entry))) { 32354a705fefSNaoya Horiguchi swp_entry_t swp_entry = pte_to_swp_entry(entry); 32364a705fefSNaoya Horiguchi 32374a705fefSNaoya Horiguchi if (is_write_migration_entry(swp_entry) && cow) { 32384a705fefSNaoya Horiguchi /* 32394a705fefSNaoya Horiguchi * COW mappings require pages in both 32404a705fefSNaoya Horiguchi * parent and child to be set to read. 32414a705fefSNaoya Horiguchi */ 32424a705fefSNaoya Horiguchi make_migration_entry_read(&swp_entry); 32434a705fefSNaoya Horiguchi entry = swp_entry_to_pte(swp_entry); 32444a705fefSNaoya Horiguchi set_huge_pte_at(src, addr, src_pte, entry); 32454a705fefSNaoya Horiguchi } 32464a705fefSNaoya Horiguchi set_huge_pte_at(dst, addr, dst_pte, entry); 32474a705fefSNaoya Horiguchi } else { 324834ee645eSJoerg Roedel if (cow) { 32497f2e9525SGerald Schaefer huge_ptep_set_wrprotect(src, addr, src_pte); 325034ee645eSJoerg Roedel mmu_notifier_invalidate_range(src, mmun_start, 325134ee645eSJoerg Roedel mmun_end); 325234ee645eSJoerg Roedel } 32530253d634SNaoya Horiguchi entry = huge_ptep_get(src_pte); 325463551ae0SDavid Gibson ptepage = pte_page(entry); 325563551ae0SDavid Gibson get_page(ptepage); 325653f9263bSKirill A. Shutemov page_dup_rmap(ptepage, true); 325763551ae0SDavid Gibson set_huge_pte_at(dst, addr, dst_pte, entry); 32585d317b2bSNaoya Horiguchi hugetlb_count_add(pages_per_huge_page(h), dst); 32591c59827dSHugh Dickins } 3260cb900f41SKirill A. Shutemov spin_unlock(src_ptl); 3261cb900f41SKirill A. Shutemov spin_unlock(dst_ptl); 326263551ae0SDavid Gibson } 326363551ae0SDavid Gibson 3264e8569dd2SAndreas Sandberg if (cow) 3265e8569dd2SAndreas Sandberg mmu_notifier_invalidate_range_end(src, mmun_start, mmun_end); 3266e8569dd2SAndreas Sandberg 3267e8569dd2SAndreas Sandberg return ret; 326863551ae0SDavid Gibson } 326963551ae0SDavid Gibson 327024669e58SAneesh Kumar K.V void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, 327124669e58SAneesh Kumar K.V unsigned long start, unsigned long end, 327224669e58SAneesh Kumar K.V struct page *ref_page) 327363551ae0SDavid Gibson { 327463551ae0SDavid Gibson struct mm_struct *mm = vma->vm_mm; 327563551ae0SDavid Gibson unsigned long address; 3276c7546f8fSDavid Gibson pte_t *ptep; 327763551ae0SDavid Gibson pte_t pte; 3278cb900f41SKirill A. Shutemov spinlock_t *ptl; 327963551ae0SDavid Gibson struct page *page; 3280a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 3281a5516438SAndi Kleen unsigned long sz = huge_page_size(h); 32822ec74c3eSSagi Grimberg const unsigned long mmun_start = start; /* For mmu_notifiers */ 32832ec74c3eSSagi Grimberg const unsigned long mmun_end = end; /* For mmu_notifiers */ 3284a5516438SAndi Kleen 328563551ae0SDavid Gibson WARN_ON(!is_vm_hugetlb_page(vma)); 3286a5516438SAndi Kleen BUG_ON(start & ~huge_page_mask(h)); 3287a5516438SAndi Kleen BUG_ON(end & ~huge_page_mask(h)); 328863551ae0SDavid Gibson 328924669e58SAneesh Kumar K.V tlb_start_vma(tlb, vma); 32902ec74c3eSSagi Grimberg mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); 3291569f48b8SHillf Danton address = start; 3292569f48b8SHillf Danton for (; address < end; address += sz) { 3293c7546f8fSDavid Gibson ptep = huge_pte_offset(mm, address); 3294c7546f8fSDavid Gibson if (!ptep) 3295c7546f8fSDavid Gibson continue; 3296c7546f8fSDavid Gibson 3297cb900f41SKirill A. Shutemov ptl = huge_pte_lock(h, mm, ptep); 329831d49da5SAneesh Kumar K.V if (huge_pmd_unshare(mm, &address, ptep)) { 329931d49da5SAneesh Kumar K.V spin_unlock(ptl); 330031d49da5SAneesh Kumar K.V continue; 330131d49da5SAneesh Kumar K.V } 330239dde65cSChen, Kenneth W 33036629326bSHillf Danton pte = huge_ptep_get(ptep); 330431d49da5SAneesh Kumar K.V if (huge_pte_none(pte)) { 330531d49da5SAneesh Kumar K.V spin_unlock(ptl); 330631d49da5SAneesh Kumar K.V continue; 330731d49da5SAneesh Kumar K.V } 33086629326bSHillf Danton 33096629326bSHillf Danton /* 33109fbc1f63SNaoya Horiguchi * Migrating hugepage or HWPoisoned hugepage is already 33119fbc1f63SNaoya Horiguchi * unmapped and its refcount is dropped, so just clear pte here. 33126629326bSHillf Danton */ 33139fbc1f63SNaoya Horiguchi if (unlikely(!pte_present(pte))) { 3314106c992aSGerald Schaefer huge_pte_clear(mm, address, ptep); 331531d49da5SAneesh Kumar K.V spin_unlock(ptl); 331631d49da5SAneesh Kumar K.V continue; 33178c4894c6SNaoya Horiguchi } 33186629326bSHillf Danton 33196629326bSHillf Danton page = pte_page(pte); 332004f2cbe3SMel Gorman /* 332104f2cbe3SMel Gorman * If a reference page is supplied, it is because a specific 332204f2cbe3SMel Gorman * page is being unmapped, not a range. Ensure the page we 332304f2cbe3SMel Gorman * are about to unmap is the actual page of interest. 332404f2cbe3SMel Gorman */ 332504f2cbe3SMel Gorman if (ref_page) { 332631d49da5SAneesh Kumar K.V if (page != ref_page) { 332731d49da5SAneesh Kumar K.V spin_unlock(ptl); 332831d49da5SAneesh Kumar K.V continue; 332931d49da5SAneesh Kumar K.V } 333004f2cbe3SMel Gorman /* 333104f2cbe3SMel Gorman * Mark the VMA as having unmapped its page so that 333204f2cbe3SMel Gorman * future faults in this VMA will fail rather than 333304f2cbe3SMel Gorman * looking like data was lost 333404f2cbe3SMel Gorman */ 333504f2cbe3SMel Gorman set_vma_resv_flags(vma, HPAGE_RESV_UNMAPPED); 333604f2cbe3SMel Gorman } 333704f2cbe3SMel Gorman 3338c7546f8fSDavid Gibson pte = huge_ptep_get_and_clear(mm, address, ptep); 333924669e58SAneesh Kumar K.V tlb_remove_tlb_entry(tlb, ptep, address); 3340106c992aSGerald Schaefer if (huge_pte_dirty(pte)) 33416649a386SKen Chen set_page_dirty(page); 33429e81130bSHillf Danton 33435d317b2bSNaoya Horiguchi hugetlb_count_sub(pages_per_huge_page(h), mm); 3344d281ee61SKirill A. Shutemov page_remove_rmap(page, true); 334531d49da5SAneesh Kumar K.V 3346cb900f41SKirill A. Shutemov spin_unlock(ptl); 3347e77b0852SAneesh Kumar K.V tlb_remove_page_size(tlb, page, huge_page_size(h)); 334824669e58SAneesh Kumar K.V /* 334931d49da5SAneesh Kumar K.V * Bail out after unmapping reference page if supplied 335024669e58SAneesh Kumar K.V */ 335131d49da5SAneesh Kumar K.V if (ref_page) 335231d49da5SAneesh Kumar K.V break; 3353fe1668aeSChen, Kenneth W } 33542ec74c3eSSagi Grimberg mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); 335524669e58SAneesh Kumar K.V tlb_end_vma(tlb, vma); 33561da177e4SLinus Torvalds } 335763551ae0SDavid Gibson 3358d833352aSMel Gorman void __unmap_hugepage_range_final(struct mmu_gather *tlb, 3359d833352aSMel Gorman struct vm_area_struct *vma, unsigned long start, 3360d833352aSMel Gorman unsigned long end, struct page *ref_page) 3361d833352aSMel Gorman { 3362d833352aSMel Gorman __unmap_hugepage_range(tlb, vma, start, end, ref_page); 3363d833352aSMel Gorman 3364d833352aSMel Gorman /* 3365d833352aSMel Gorman * Clear this flag so that x86's huge_pmd_share page_table_shareable 3366d833352aSMel Gorman * test will fail on a vma being torn down, and not grab a page table 3367d833352aSMel Gorman * on its way out. We're lucky that the flag has such an appropriate 3368d833352aSMel Gorman * name, and can in fact be safely cleared here. We could clear it 3369d833352aSMel Gorman * before the __unmap_hugepage_range above, but all that's necessary 3370c8c06efaSDavidlohr Bueso * is to clear it before releasing the i_mmap_rwsem. This works 3371d833352aSMel Gorman * because in the context this is called, the VMA is about to be 3372c8c06efaSDavidlohr Bueso * destroyed and the i_mmap_rwsem is held. 3373d833352aSMel Gorman */ 3374d833352aSMel Gorman vma->vm_flags &= ~VM_MAYSHARE; 3375d833352aSMel Gorman } 3376d833352aSMel Gorman 3377502717f4SChen, Kenneth W void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, 337804f2cbe3SMel Gorman unsigned long end, struct page *ref_page) 3379502717f4SChen, Kenneth W { 338024669e58SAneesh Kumar K.V struct mm_struct *mm; 338124669e58SAneesh Kumar K.V struct mmu_gather tlb; 338224669e58SAneesh Kumar K.V 338324669e58SAneesh Kumar K.V mm = vma->vm_mm; 338424669e58SAneesh Kumar K.V 33852b047252SLinus Torvalds tlb_gather_mmu(&tlb, mm, start, end); 338624669e58SAneesh Kumar K.V __unmap_hugepage_range(&tlb, vma, start, end, ref_page); 338724669e58SAneesh Kumar K.V tlb_finish_mmu(&tlb, start, end); 3388502717f4SChen, Kenneth W } 3389502717f4SChen, Kenneth W 339004f2cbe3SMel Gorman /* 339104f2cbe3SMel Gorman * This is called when the original mapper is failing to COW a MAP_PRIVATE 339204f2cbe3SMel Gorman * mappping it owns the reserve page for. The intention is to unmap the page 339304f2cbe3SMel Gorman * from other VMAs and let the children be SIGKILLed if they are faulting the 339404f2cbe3SMel Gorman * same region. 339504f2cbe3SMel Gorman */ 33962f4612afSDavidlohr Bueso static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, 33972a4b3dedSHarvey Harrison struct page *page, unsigned long address) 339804f2cbe3SMel Gorman { 33997526674dSAdam Litke struct hstate *h = hstate_vma(vma); 340004f2cbe3SMel Gorman struct vm_area_struct *iter_vma; 340104f2cbe3SMel Gorman struct address_space *mapping; 340204f2cbe3SMel Gorman pgoff_t pgoff; 340304f2cbe3SMel Gorman 340404f2cbe3SMel Gorman /* 340504f2cbe3SMel Gorman * vm_pgoff is in PAGE_SIZE units, hence the different calculation 340604f2cbe3SMel Gorman * from page cache lookup which is in HPAGE_SIZE units. 340704f2cbe3SMel Gorman */ 34087526674dSAdam Litke address = address & huge_page_mask(h); 340936e4f20aSMichal Hocko pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + 341036e4f20aSMichal Hocko vma->vm_pgoff; 341193c76a3dSAl Viro mapping = vma->vm_file->f_mapping; 341204f2cbe3SMel Gorman 34134eb2b1dcSMel Gorman /* 34144eb2b1dcSMel Gorman * Take the mapping lock for the duration of the table walk. As 34154eb2b1dcSMel Gorman * this mapping should be shared between all the VMAs, 34164eb2b1dcSMel Gorman * __unmap_hugepage_range() is called as the lock is already held 34174eb2b1dcSMel Gorman */ 341883cde9e8SDavidlohr Bueso i_mmap_lock_write(mapping); 34196b2dbba8SMichel Lespinasse vma_interval_tree_foreach(iter_vma, &mapping->i_mmap, pgoff, pgoff) { 342004f2cbe3SMel Gorman /* Do not unmap the current VMA */ 342104f2cbe3SMel Gorman if (iter_vma == vma) 342204f2cbe3SMel Gorman continue; 342304f2cbe3SMel Gorman 342404f2cbe3SMel Gorman /* 34252f84a899SMel Gorman * Shared VMAs have their own reserves and do not affect 34262f84a899SMel Gorman * MAP_PRIVATE accounting but it is possible that a shared 34272f84a899SMel Gorman * VMA is using the same page so check and skip such VMAs. 34282f84a899SMel Gorman */ 34292f84a899SMel Gorman if (iter_vma->vm_flags & VM_MAYSHARE) 34302f84a899SMel Gorman continue; 34312f84a899SMel Gorman 34322f84a899SMel Gorman /* 343304f2cbe3SMel Gorman * Unmap the page from other VMAs without their own reserves. 343404f2cbe3SMel Gorman * They get marked to be SIGKILLed if they fault in these 343504f2cbe3SMel Gorman * areas. This is because a future no-page fault on this VMA 343604f2cbe3SMel Gorman * could insert a zeroed page instead of the data existing 343704f2cbe3SMel Gorman * from the time of fork. This would look like data corruption 343804f2cbe3SMel Gorman */ 343904f2cbe3SMel Gorman if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER)) 344024669e58SAneesh Kumar K.V unmap_hugepage_range(iter_vma, address, 344124669e58SAneesh Kumar K.V address + huge_page_size(h), page); 344204f2cbe3SMel Gorman } 344383cde9e8SDavidlohr Bueso i_mmap_unlock_write(mapping); 344404f2cbe3SMel Gorman } 344504f2cbe3SMel Gorman 34460fe6e20bSNaoya Horiguchi /* 34470fe6e20bSNaoya Horiguchi * Hugetlb_cow() should be called with page lock of the original hugepage held. 3448ef009b25SMichal Hocko * Called with hugetlb_instantiation_mutex held and pte_page locked so we 3449ef009b25SMichal Hocko * cannot race with other handlers or page migration. 3450ef009b25SMichal Hocko * Keep the pte_same checks anyway to make transition from the mutex easier. 34510fe6e20bSNaoya Horiguchi */ 34521e8f889bSDavid Gibson static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, 34533999f52eSAneesh Kumar K.V unsigned long address, pte_t *ptep, 3454cb900f41SKirill A. Shutemov struct page *pagecache_page, spinlock_t *ptl) 34551e8f889bSDavid Gibson { 34563999f52eSAneesh Kumar K.V pte_t pte; 3457a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 34581e8f889bSDavid Gibson struct page *old_page, *new_page; 3459ad4404a2SDavidlohr Bueso int ret = 0, outside_reserve = 0; 34602ec74c3eSSagi Grimberg unsigned long mmun_start; /* For mmu_notifiers */ 34612ec74c3eSSagi Grimberg unsigned long mmun_end; /* For mmu_notifiers */ 34621e8f889bSDavid Gibson 34633999f52eSAneesh Kumar K.V pte = huge_ptep_get(ptep); 34641e8f889bSDavid Gibson old_page = pte_page(pte); 34651e8f889bSDavid Gibson 346604f2cbe3SMel Gorman retry_avoidcopy: 34671e8f889bSDavid Gibson /* If no-one else is actually using this page, avoid the copy 34681e8f889bSDavid Gibson * and just make the page writable */ 346937a2140dSJoonsoo Kim if (page_mapcount(old_page) == 1 && PageAnon(old_page)) { 34705a49973dSHugh Dickins page_move_anon_rmap(old_page, vma); 34711e8f889bSDavid Gibson set_huge_ptep_writable(vma, address, ptep); 347283c54070SNick Piggin return 0; 34731e8f889bSDavid Gibson } 34741e8f889bSDavid Gibson 347504f2cbe3SMel Gorman /* 347604f2cbe3SMel Gorman * If the process that created a MAP_PRIVATE mapping is about to 347704f2cbe3SMel Gorman * perform a COW due to a shared page count, attempt to satisfy 347804f2cbe3SMel Gorman * the allocation without using the existing reserves. The pagecache 347904f2cbe3SMel Gorman * page is used to determine if the reserve at this address was 348004f2cbe3SMel Gorman * consumed or not. If reserves were used, a partial faulted mapping 348104f2cbe3SMel Gorman * at the time of fork() could consume its reserves on COW instead 348204f2cbe3SMel Gorman * of the full address range. 348304f2cbe3SMel Gorman */ 34845944d011SJoonsoo Kim if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) && 348504f2cbe3SMel Gorman old_page != pagecache_page) 348604f2cbe3SMel Gorman outside_reserve = 1; 348704f2cbe3SMel Gorman 348809cbfeafSKirill A. Shutemov get_page(old_page); 3489b76c8cfbSLarry Woodman 3490ad4404a2SDavidlohr Bueso /* 3491ad4404a2SDavidlohr Bueso * Drop page table lock as buddy allocator may be called. It will 3492ad4404a2SDavidlohr Bueso * be acquired again before returning to the caller, as expected. 3493ad4404a2SDavidlohr Bueso */ 3494cb900f41SKirill A. Shutemov spin_unlock(ptl); 349504f2cbe3SMel Gorman new_page = alloc_huge_page(vma, address, outside_reserve); 34961e8f889bSDavid Gibson 34972fc39cecSAdam Litke if (IS_ERR(new_page)) { 349804f2cbe3SMel Gorman /* 349904f2cbe3SMel Gorman * If a process owning a MAP_PRIVATE mapping fails to COW, 350004f2cbe3SMel Gorman * it is due to references held by a child and an insufficient 350104f2cbe3SMel Gorman * huge page pool. To guarantee the original mappers 350204f2cbe3SMel Gorman * reliability, unmap the page from child processes. The child 350304f2cbe3SMel Gorman * may get SIGKILLed if it later faults. 350404f2cbe3SMel Gorman */ 350504f2cbe3SMel Gorman if (outside_reserve) { 350609cbfeafSKirill A. Shutemov put_page(old_page); 350704f2cbe3SMel Gorman BUG_ON(huge_pte_none(pte)); 35082f4612afSDavidlohr Bueso unmap_ref_private(mm, vma, old_page, address); 350904f2cbe3SMel Gorman BUG_ON(huge_pte_none(pte)); 3510cb900f41SKirill A. Shutemov spin_lock(ptl); 3511a734bcc8SHillf Danton ptep = huge_pte_offset(mm, address & huge_page_mask(h)); 3512a9af0c5dSNaoya Horiguchi if (likely(ptep && 3513a9af0c5dSNaoya Horiguchi pte_same(huge_ptep_get(ptep), pte))) 351404f2cbe3SMel Gorman goto retry_avoidcopy; 3515a734bcc8SHillf Danton /* 3516cb900f41SKirill A. Shutemov * race occurs while re-acquiring page table 3517cb900f41SKirill A. Shutemov * lock, and our job is done. 3518a734bcc8SHillf Danton */ 3519a734bcc8SHillf Danton return 0; 352004f2cbe3SMel Gorman } 352104f2cbe3SMel Gorman 3522ad4404a2SDavidlohr Bueso ret = (PTR_ERR(new_page) == -ENOMEM) ? 3523ad4404a2SDavidlohr Bueso VM_FAULT_OOM : VM_FAULT_SIGBUS; 3524ad4404a2SDavidlohr Bueso goto out_release_old; 35251e8f889bSDavid Gibson } 35261e8f889bSDavid Gibson 35270fe6e20bSNaoya Horiguchi /* 35280fe6e20bSNaoya Horiguchi * When the original hugepage is shared one, it does not have 35290fe6e20bSNaoya Horiguchi * anon_vma prepared. 35300fe6e20bSNaoya Horiguchi */ 353144e2aa93SDean Nelson if (unlikely(anon_vma_prepare(vma))) { 3532ad4404a2SDavidlohr Bueso ret = VM_FAULT_OOM; 3533ad4404a2SDavidlohr Bueso goto out_release_all; 353444e2aa93SDean Nelson } 35350fe6e20bSNaoya Horiguchi 353647ad8475SAndrea Arcangeli copy_user_huge_page(new_page, old_page, address, vma, 353747ad8475SAndrea Arcangeli pages_per_huge_page(h)); 35380ed361deSNick Piggin __SetPageUptodate(new_page); 3539bcc54222SNaoya Horiguchi set_page_huge_active(new_page); 35401e8f889bSDavid Gibson 35412ec74c3eSSagi Grimberg mmun_start = address & huge_page_mask(h); 35422ec74c3eSSagi Grimberg mmun_end = mmun_start + huge_page_size(h); 35432ec74c3eSSagi Grimberg mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); 3544ad4404a2SDavidlohr Bueso 3545b76c8cfbSLarry Woodman /* 3546cb900f41SKirill A. Shutemov * Retake the page table lock to check for racing updates 3547b76c8cfbSLarry Woodman * before the page tables are altered 3548b76c8cfbSLarry Woodman */ 3549cb900f41SKirill A. Shutemov spin_lock(ptl); 3550a5516438SAndi Kleen ptep = huge_pte_offset(mm, address & huge_page_mask(h)); 3551a9af0c5dSNaoya Horiguchi if (likely(ptep && pte_same(huge_ptep_get(ptep), pte))) { 355207443a85SJoonsoo Kim ClearPagePrivate(new_page); 355307443a85SJoonsoo Kim 35541e8f889bSDavid Gibson /* Break COW */ 35558fe627ecSGerald Schaefer huge_ptep_clear_flush(vma, address, ptep); 355634ee645eSJoerg Roedel mmu_notifier_invalidate_range(mm, mmun_start, mmun_end); 35571e8f889bSDavid Gibson set_huge_pte_at(mm, address, ptep, 35581e8f889bSDavid Gibson make_huge_pte(vma, new_page, 1)); 3559d281ee61SKirill A. Shutemov page_remove_rmap(old_page, true); 3560cd67f0d2SNaoya Horiguchi hugepage_add_new_anon_rmap(new_page, vma, address); 35611e8f889bSDavid Gibson /* Make the old page be freed below */ 35621e8f889bSDavid Gibson new_page = old_page; 35631e8f889bSDavid Gibson } 3564cb900f41SKirill A. Shutemov spin_unlock(ptl); 35652ec74c3eSSagi Grimberg mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); 3566ad4404a2SDavidlohr Bueso out_release_all: 356796b96a96SMike Kravetz restore_reserve_on_error(h, vma, address, new_page); 356809cbfeafSKirill A. Shutemov put_page(new_page); 3569ad4404a2SDavidlohr Bueso out_release_old: 357009cbfeafSKirill A. Shutemov put_page(old_page); 35718312034fSJoonsoo Kim 3572ad4404a2SDavidlohr Bueso spin_lock(ptl); /* Caller expects lock to be held */ 3573ad4404a2SDavidlohr Bueso return ret; 35741e8f889bSDavid Gibson } 35751e8f889bSDavid Gibson 357604f2cbe3SMel Gorman /* Return the pagecache page at a given address within a VMA */ 3577a5516438SAndi Kleen static struct page *hugetlbfs_pagecache_page(struct hstate *h, 3578a5516438SAndi Kleen struct vm_area_struct *vma, unsigned long address) 357904f2cbe3SMel Gorman { 358004f2cbe3SMel Gorman struct address_space *mapping; 3581e7c4b0bfSAndy Whitcroft pgoff_t idx; 358204f2cbe3SMel Gorman 358304f2cbe3SMel Gorman mapping = vma->vm_file->f_mapping; 3584a5516438SAndi Kleen idx = vma_hugecache_offset(h, vma, address); 358504f2cbe3SMel Gorman 358604f2cbe3SMel Gorman return find_lock_page(mapping, idx); 358704f2cbe3SMel Gorman } 358804f2cbe3SMel Gorman 35893ae77f43SHugh Dickins /* 35903ae77f43SHugh Dickins * Return whether there is a pagecache page to back given address within VMA. 35913ae77f43SHugh Dickins * Caller follow_hugetlb_page() holds page_table_lock so we cannot lock_page. 35923ae77f43SHugh Dickins */ 35933ae77f43SHugh Dickins static bool hugetlbfs_pagecache_present(struct hstate *h, 35942a15efc9SHugh Dickins struct vm_area_struct *vma, unsigned long address) 35952a15efc9SHugh Dickins { 35962a15efc9SHugh Dickins struct address_space *mapping; 35972a15efc9SHugh Dickins pgoff_t idx; 35982a15efc9SHugh Dickins struct page *page; 35992a15efc9SHugh Dickins 36002a15efc9SHugh Dickins mapping = vma->vm_file->f_mapping; 36012a15efc9SHugh Dickins idx = vma_hugecache_offset(h, vma, address); 36022a15efc9SHugh Dickins 36032a15efc9SHugh Dickins page = find_get_page(mapping, idx); 36042a15efc9SHugh Dickins if (page) 36052a15efc9SHugh Dickins put_page(page); 36062a15efc9SHugh Dickins return page != NULL; 36072a15efc9SHugh Dickins } 36082a15efc9SHugh Dickins 3609ab76ad54SMike Kravetz int huge_add_to_page_cache(struct page *page, struct address_space *mapping, 3610ab76ad54SMike Kravetz pgoff_t idx) 3611ab76ad54SMike Kravetz { 3612ab76ad54SMike Kravetz struct inode *inode = mapping->host; 3613ab76ad54SMike Kravetz struct hstate *h = hstate_inode(inode); 3614ab76ad54SMike Kravetz int err = add_to_page_cache(page, mapping, idx, GFP_KERNEL); 3615ab76ad54SMike Kravetz 3616ab76ad54SMike Kravetz if (err) 3617ab76ad54SMike Kravetz return err; 3618ab76ad54SMike Kravetz ClearPagePrivate(page); 3619ab76ad54SMike Kravetz 3620ab76ad54SMike Kravetz spin_lock(&inode->i_lock); 3621ab76ad54SMike Kravetz inode->i_blocks += blocks_per_huge_page(h); 3622ab76ad54SMike Kravetz spin_unlock(&inode->i_lock); 3623ab76ad54SMike Kravetz return 0; 3624ab76ad54SMike Kravetz } 3625ab76ad54SMike Kravetz 3626a1ed3ddaSRobert P. J. Day static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma, 36278382d914SDavidlohr Bueso struct address_space *mapping, pgoff_t idx, 3628788c7df4SHugh Dickins unsigned long address, pte_t *ptep, unsigned int flags) 3629ac9b9c66SHugh Dickins { 3630a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 3631ac9b9c66SHugh Dickins int ret = VM_FAULT_SIGBUS; 3632409eb8c2SHillf Danton int anon_rmap = 0; 36334c887265SAdam Litke unsigned long size; 36344c887265SAdam Litke struct page *page; 36351e8f889bSDavid Gibson pte_t new_pte; 3636cb900f41SKirill A. Shutemov spinlock_t *ptl; 36374c887265SAdam Litke 363804f2cbe3SMel Gorman /* 363904f2cbe3SMel Gorman * Currently, we are forced to kill the process in the event the 364004f2cbe3SMel Gorman * original mapper has unmapped pages from the child due to a failed 364125985edcSLucas De Marchi * COW. Warn that such a situation has occurred as it may not be obvious 364204f2cbe3SMel Gorman */ 364304f2cbe3SMel Gorman if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) { 3644910154d5SGeoffrey Thomas pr_warn_ratelimited("PID %d killed due to inadequate hugepage pool\n", 364504f2cbe3SMel Gorman current->pid); 364604f2cbe3SMel Gorman return ret; 364704f2cbe3SMel Gorman } 364804f2cbe3SMel Gorman 36494c887265SAdam Litke /* 36504c887265SAdam Litke * Use page lock to guard against racing truncation 36514c887265SAdam Litke * before we get page_table_lock. 36524c887265SAdam Litke */ 36536bda666aSChristoph Lameter retry: 36546bda666aSChristoph Lameter page = find_lock_page(mapping, idx); 36556bda666aSChristoph Lameter if (!page) { 3656a5516438SAndi Kleen size = i_size_read(mapping->host) >> huge_page_shift(h); 3657ebed4bfcSHugh Dickins if (idx >= size) 3658ebed4bfcSHugh Dickins goto out; 365904f2cbe3SMel Gorman page = alloc_huge_page(vma, address, 0); 36602fc39cecSAdam Litke if (IS_ERR(page)) { 366176dcee75SAneesh Kumar K.V ret = PTR_ERR(page); 366276dcee75SAneesh Kumar K.V if (ret == -ENOMEM) 366376dcee75SAneesh Kumar K.V ret = VM_FAULT_OOM; 366476dcee75SAneesh Kumar K.V else 366576dcee75SAneesh Kumar K.V ret = VM_FAULT_SIGBUS; 36666bda666aSChristoph Lameter goto out; 36676bda666aSChristoph Lameter } 366847ad8475SAndrea Arcangeli clear_huge_page(page, address, pages_per_huge_page(h)); 36690ed361deSNick Piggin __SetPageUptodate(page); 3670bcc54222SNaoya Horiguchi set_page_huge_active(page); 3671ac9b9c66SHugh Dickins 3672f83a275dSMel Gorman if (vma->vm_flags & VM_MAYSHARE) { 3673ab76ad54SMike Kravetz int err = huge_add_to_page_cache(page, mapping, idx); 36746bda666aSChristoph Lameter if (err) { 36756bda666aSChristoph Lameter put_page(page); 36766bda666aSChristoph Lameter if (err == -EEXIST) 36776bda666aSChristoph Lameter goto retry; 36786bda666aSChristoph Lameter goto out; 36796bda666aSChristoph Lameter } 368023be7468SMel Gorman } else { 36816bda666aSChristoph Lameter lock_page(page); 36820fe6e20bSNaoya Horiguchi if (unlikely(anon_vma_prepare(vma))) { 36830fe6e20bSNaoya Horiguchi ret = VM_FAULT_OOM; 36840fe6e20bSNaoya Horiguchi goto backout_unlocked; 368523be7468SMel Gorman } 3686409eb8c2SHillf Danton anon_rmap = 1; 36870fe6e20bSNaoya Horiguchi } 36880fe6e20bSNaoya Horiguchi } else { 368957303d80SAndy Whitcroft /* 3690998b4382SNaoya Horiguchi * If memory error occurs between mmap() and fault, some process 3691998b4382SNaoya Horiguchi * don't have hwpoisoned swap entry for errored virtual address. 3692998b4382SNaoya Horiguchi * So we need to block hugepage fault by PG_hwpoison bit check. 3693fd6a03edSNaoya Horiguchi */ 3694fd6a03edSNaoya Horiguchi if (unlikely(PageHWPoison(page))) { 3695aa50d3a7SAndi Kleen ret = VM_FAULT_HWPOISON | 3696972dc4deSAneesh Kumar K.V VM_FAULT_SET_HINDEX(hstate_index(h)); 3697fd6a03edSNaoya Horiguchi goto backout_unlocked; 36986bda666aSChristoph Lameter } 3699998b4382SNaoya Horiguchi } 37001e8f889bSDavid Gibson 370157303d80SAndy Whitcroft /* 370257303d80SAndy Whitcroft * If we are going to COW a private mapping later, we examine the 370357303d80SAndy Whitcroft * pending reservations for this page now. This will ensure that 370457303d80SAndy Whitcroft * any allocations necessary to record that reservation occur outside 370557303d80SAndy Whitcroft * the spinlock. 370657303d80SAndy Whitcroft */ 37075e911373SMike Kravetz if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { 37082b26736cSAndy Whitcroft if (vma_needs_reservation(h, vma, address) < 0) { 37092b26736cSAndy Whitcroft ret = VM_FAULT_OOM; 37102b26736cSAndy Whitcroft goto backout_unlocked; 37112b26736cSAndy Whitcroft } 37125e911373SMike Kravetz /* Just decrements count, does not deallocate */ 3713feba16e2SMike Kravetz vma_end_reservation(h, vma, address); 37145e911373SMike Kravetz } 371557303d80SAndy Whitcroft 37168bea8052SAneesh Kumar K.V ptl = huge_pte_lock(h, mm, ptep); 3717a5516438SAndi Kleen size = i_size_read(mapping->host) >> huge_page_shift(h); 37184c887265SAdam Litke if (idx >= size) 37194c887265SAdam Litke goto backout; 37204c887265SAdam Litke 372183c54070SNick Piggin ret = 0; 37227f2e9525SGerald Schaefer if (!huge_pte_none(huge_ptep_get(ptep))) 37234c887265SAdam Litke goto backout; 37244c887265SAdam Litke 372507443a85SJoonsoo Kim if (anon_rmap) { 372607443a85SJoonsoo Kim ClearPagePrivate(page); 3727409eb8c2SHillf Danton hugepage_add_new_anon_rmap(page, vma, address); 3728ac714904SChoi Gi-yong } else 372953f9263bSKirill A. Shutemov page_dup_rmap(page, true); 37301e8f889bSDavid Gibson new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) 37311e8f889bSDavid Gibson && (vma->vm_flags & VM_SHARED))); 37321e8f889bSDavid Gibson set_huge_pte_at(mm, address, ptep, new_pte); 37331e8f889bSDavid Gibson 37345d317b2bSNaoya Horiguchi hugetlb_count_add(pages_per_huge_page(h), mm); 3735788c7df4SHugh Dickins if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) { 37361e8f889bSDavid Gibson /* Optimization, do the COW without a second fault */ 37373999f52eSAneesh Kumar K.V ret = hugetlb_cow(mm, vma, address, ptep, page, ptl); 37381e8f889bSDavid Gibson } 37391e8f889bSDavid Gibson 3740cb900f41SKirill A. Shutemov spin_unlock(ptl); 37414c887265SAdam Litke unlock_page(page); 37424c887265SAdam Litke out: 3743ac9b9c66SHugh Dickins return ret; 37444c887265SAdam Litke 37454c887265SAdam Litke backout: 3746cb900f41SKirill A. Shutemov spin_unlock(ptl); 37472b26736cSAndy Whitcroft backout_unlocked: 37484c887265SAdam Litke unlock_page(page); 374996b96a96SMike Kravetz restore_reserve_on_error(h, vma, address, page); 37504c887265SAdam Litke put_page(page); 37514c887265SAdam Litke goto out; 3752ac9b9c66SHugh Dickins } 3753ac9b9c66SHugh Dickins 37548382d914SDavidlohr Bueso #ifdef CONFIG_SMP 3755c672c7f2SMike Kravetz u32 hugetlb_fault_mutex_hash(struct hstate *h, struct mm_struct *mm, 37568382d914SDavidlohr Bueso struct vm_area_struct *vma, 37578382d914SDavidlohr Bueso struct address_space *mapping, 37588382d914SDavidlohr Bueso pgoff_t idx, unsigned long address) 37598382d914SDavidlohr Bueso { 37608382d914SDavidlohr Bueso unsigned long key[2]; 37618382d914SDavidlohr Bueso u32 hash; 37628382d914SDavidlohr Bueso 37638382d914SDavidlohr Bueso if (vma->vm_flags & VM_SHARED) { 37648382d914SDavidlohr Bueso key[0] = (unsigned long) mapping; 37658382d914SDavidlohr Bueso key[1] = idx; 37668382d914SDavidlohr Bueso } else { 37678382d914SDavidlohr Bueso key[0] = (unsigned long) mm; 37688382d914SDavidlohr Bueso key[1] = address >> huge_page_shift(h); 37698382d914SDavidlohr Bueso } 37708382d914SDavidlohr Bueso 37718382d914SDavidlohr Bueso hash = jhash2((u32 *)&key, sizeof(key)/sizeof(u32), 0); 37728382d914SDavidlohr Bueso 37738382d914SDavidlohr Bueso return hash & (num_fault_mutexes - 1); 37748382d914SDavidlohr Bueso } 37758382d914SDavidlohr Bueso #else 37768382d914SDavidlohr Bueso /* 37778382d914SDavidlohr Bueso * For uniprocesor systems we always use a single mutex, so just 37788382d914SDavidlohr Bueso * return 0 and avoid the hashing overhead. 37798382d914SDavidlohr Bueso */ 3780c672c7f2SMike Kravetz u32 hugetlb_fault_mutex_hash(struct hstate *h, struct mm_struct *mm, 37818382d914SDavidlohr Bueso struct vm_area_struct *vma, 37828382d914SDavidlohr Bueso struct address_space *mapping, 37838382d914SDavidlohr Bueso pgoff_t idx, unsigned long address) 37848382d914SDavidlohr Bueso { 37858382d914SDavidlohr Bueso return 0; 37868382d914SDavidlohr Bueso } 37878382d914SDavidlohr Bueso #endif 37888382d914SDavidlohr Bueso 378986e5216fSAdam Litke int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, 3790788c7df4SHugh Dickins unsigned long address, unsigned int flags) 379186e5216fSAdam Litke { 37928382d914SDavidlohr Bueso pte_t *ptep, entry; 3793cb900f41SKirill A. Shutemov spinlock_t *ptl; 37941e8f889bSDavid Gibson int ret; 37958382d914SDavidlohr Bueso u32 hash; 37968382d914SDavidlohr Bueso pgoff_t idx; 37970fe6e20bSNaoya Horiguchi struct page *page = NULL; 379857303d80SAndy Whitcroft struct page *pagecache_page = NULL; 3799a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 38008382d914SDavidlohr Bueso struct address_space *mapping; 38010f792cf9SNaoya Horiguchi int need_wait_lock = 0; 380286e5216fSAdam Litke 38031e16a539SKAMEZAWA Hiroyuki address &= huge_page_mask(h); 38041e16a539SKAMEZAWA Hiroyuki 3805fd6a03edSNaoya Horiguchi ptep = huge_pte_offset(mm, address); 3806fd6a03edSNaoya Horiguchi if (ptep) { 3807fd6a03edSNaoya Horiguchi entry = huge_ptep_get(ptep); 3808290408d4SNaoya Horiguchi if (unlikely(is_hugetlb_entry_migration(entry))) { 3809cb900f41SKirill A. Shutemov migration_entry_wait_huge(vma, mm, ptep); 3810290408d4SNaoya Horiguchi return 0; 3811290408d4SNaoya Horiguchi } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) 3812aa50d3a7SAndi Kleen return VM_FAULT_HWPOISON_LARGE | 3813972dc4deSAneesh Kumar K.V VM_FAULT_SET_HINDEX(hstate_index(h)); 38140d777df5SNaoya Horiguchi } else { 3815a5516438SAndi Kleen ptep = huge_pte_alloc(mm, address, huge_page_size(h)); 381686e5216fSAdam Litke if (!ptep) 381786e5216fSAdam Litke return VM_FAULT_OOM; 38180d777df5SNaoya Horiguchi } 381986e5216fSAdam Litke 38208382d914SDavidlohr Bueso mapping = vma->vm_file->f_mapping; 38218382d914SDavidlohr Bueso idx = vma_hugecache_offset(h, vma, address); 38228382d914SDavidlohr Bueso 38233935baa9SDavid Gibson /* 38243935baa9SDavid Gibson * Serialize hugepage allocation and instantiation, so that we don't 38253935baa9SDavid Gibson * get spurious allocation failures if two CPUs race to instantiate 38263935baa9SDavid Gibson * the same page in the page cache. 38273935baa9SDavid Gibson */ 3828c672c7f2SMike Kravetz hash = hugetlb_fault_mutex_hash(h, mm, vma, mapping, idx, address); 3829c672c7f2SMike Kravetz mutex_lock(&hugetlb_fault_mutex_table[hash]); 38308382d914SDavidlohr Bueso 38317f2e9525SGerald Schaefer entry = huge_ptep_get(ptep); 38327f2e9525SGerald Schaefer if (huge_pte_none(entry)) { 38338382d914SDavidlohr Bueso ret = hugetlb_no_page(mm, vma, mapping, idx, address, ptep, flags); 3834b4d1d99fSDavid Gibson goto out_mutex; 38353935baa9SDavid Gibson } 383686e5216fSAdam Litke 383783c54070SNick Piggin ret = 0; 38381e8f889bSDavid Gibson 383957303d80SAndy Whitcroft /* 38400f792cf9SNaoya Horiguchi * entry could be a migration/hwpoison entry at this point, so this 38410f792cf9SNaoya Horiguchi * check prevents the kernel from going below assuming that we have 38420f792cf9SNaoya Horiguchi * a active hugepage in pagecache. This goto expects the 2nd page fault, 38430f792cf9SNaoya Horiguchi * and is_hugetlb_entry_(migration|hwpoisoned) check will properly 38440f792cf9SNaoya Horiguchi * handle it. 38450f792cf9SNaoya Horiguchi */ 38460f792cf9SNaoya Horiguchi if (!pte_present(entry)) 38470f792cf9SNaoya Horiguchi goto out_mutex; 38480f792cf9SNaoya Horiguchi 38490f792cf9SNaoya Horiguchi /* 385057303d80SAndy Whitcroft * If we are going to COW the mapping later, we examine the pending 385157303d80SAndy Whitcroft * reservations for this page now. This will ensure that any 385257303d80SAndy Whitcroft * allocations necessary to record that reservation occur outside the 385357303d80SAndy Whitcroft * spinlock. For private mappings, we also lookup the pagecache 385457303d80SAndy Whitcroft * page now as it is used to determine if a reservation has been 385557303d80SAndy Whitcroft * consumed. 385657303d80SAndy Whitcroft */ 3857106c992aSGerald Schaefer if ((flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) { 38582b26736cSAndy Whitcroft if (vma_needs_reservation(h, vma, address) < 0) { 38592b26736cSAndy Whitcroft ret = VM_FAULT_OOM; 3860b4d1d99fSDavid Gibson goto out_mutex; 38612b26736cSAndy Whitcroft } 38625e911373SMike Kravetz /* Just decrements count, does not deallocate */ 3863feba16e2SMike Kravetz vma_end_reservation(h, vma, address); 386457303d80SAndy Whitcroft 3865f83a275dSMel Gorman if (!(vma->vm_flags & VM_MAYSHARE)) 386657303d80SAndy Whitcroft pagecache_page = hugetlbfs_pagecache_page(h, 386757303d80SAndy Whitcroft vma, address); 386857303d80SAndy Whitcroft } 386957303d80SAndy Whitcroft 38700f792cf9SNaoya Horiguchi ptl = huge_pte_lock(h, mm, ptep); 38710fe6e20bSNaoya Horiguchi 38721e8f889bSDavid Gibson /* Check for a racing update before calling hugetlb_cow */ 3873b4d1d99fSDavid Gibson if (unlikely(!pte_same(entry, huge_ptep_get(ptep)))) 3874cb900f41SKirill A. Shutemov goto out_ptl; 3875b4d1d99fSDavid Gibson 38760f792cf9SNaoya Horiguchi /* 38770f792cf9SNaoya Horiguchi * hugetlb_cow() requires page locks of pte_page(entry) and 38780f792cf9SNaoya Horiguchi * pagecache_page, so here we need take the former one 38790f792cf9SNaoya Horiguchi * when page != pagecache_page or !pagecache_page. 38800f792cf9SNaoya Horiguchi */ 38810f792cf9SNaoya Horiguchi page = pte_page(entry); 38820f792cf9SNaoya Horiguchi if (page != pagecache_page) 38830f792cf9SNaoya Horiguchi if (!trylock_page(page)) { 38840f792cf9SNaoya Horiguchi need_wait_lock = 1; 38850f792cf9SNaoya Horiguchi goto out_ptl; 38860f792cf9SNaoya Horiguchi } 38870f792cf9SNaoya Horiguchi 38880f792cf9SNaoya Horiguchi get_page(page); 3889b4d1d99fSDavid Gibson 3890788c7df4SHugh Dickins if (flags & FAULT_FLAG_WRITE) { 3891106c992aSGerald Schaefer if (!huge_pte_write(entry)) { 38923999f52eSAneesh Kumar K.V ret = hugetlb_cow(mm, vma, address, ptep, 3893cb900f41SKirill A. Shutemov pagecache_page, ptl); 38940f792cf9SNaoya Horiguchi goto out_put_page; 3895b4d1d99fSDavid Gibson } 3896106c992aSGerald Schaefer entry = huge_pte_mkdirty(entry); 3897b4d1d99fSDavid Gibson } 3898b4d1d99fSDavid Gibson entry = pte_mkyoung(entry); 3899788c7df4SHugh Dickins if (huge_ptep_set_access_flags(vma, address, ptep, entry, 3900788c7df4SHugh Dickins flags & FAULT_FLAG_WRITE)) 39014b3073e1SRussell King update_mmu_cache(vma, address, ptep); 39020f792cf9SNaoya Horiguchi out_put_page: 39030f792cf9SNaoya Horiguchi if (page != pagecache_page) 39040f792cf9SNaoya Horiguchi unlock_page(page); 39050f792cf9SNaoya Horiguchi put_page(page); 3906cb900f41SKirill A. Shutemov out_ptl: 3907cb900f41SKirill A. Shutemov spin_unlock(ptl); 390857303d80SAndy Whitcroft 390957303d80SAndy Whitcroft if (pagecache_page) { 391057303d80SAndy Whitcroft unlock_page(pagecache_page); 391157303d80SAndy Whitcroft put_page(pagecache_page); 391257303d80SAndy Whitcroft } 3913b4d1d99fSDavid Gibson out_mutex: 3914c672c7f2SMike Kravetz mutex_unlock(&hugetlb_fault_mutex_table[hash]); 39150f792cf9SNaoya Horiguchi /* 39160f792cf9SNaoya Horiguchi * Generally it's safe to hold refcount during waiting page lock. But 39170f792cf9SNaoya Horiguchi * here we just wait to defer the next page fault to avoid busy loop and 39180f792cf9SNaoya Horiguchi * the page is not used after unlocked before returning from the current 39190f792cf9SNaoya Horiguchi * page fault. So we are safe from accessing freed page, even if we wait 39200f792cf9SNaoya Horiguchi * here without taking refcount. 39210f792cf9SNaoya Horiguchi */ 39220f792cf9SNaoya Horiguchi if (need_wait_lock) 39230f792cf9SNaoya Horiguchi wait_on_page_locked(page); 39241e8f889bSDavid Gibson return ret; 392586e5216fSAdam Litke } 392686e5216fSAdam Litke 392728a35716SMichel Lespinasse long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, 392863551ae0SDavid Gibson struct page **pages, struct vm_area_struct **vmas, 392928a35716SMichel Lespinasse unsigned long *position, unsigned long *nr_pages, 393028a35716SMichel Lespinasse long i, unsigned int flags) 393163551ae0SDavid Gibson { 3932d5d4b0aaSChen, Kenneth W unsigned long pfn_offset; 3933d5d4b0aaSChen, Kenneth W unsigned long vaddr = *position; 393428a35716SMichel Lespinasse unsigned long remainder = *nr_pages; 3935a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 393663551ae0SDavid Gibson 393763551ae0SDavid Gibson while (vaddr < vma->vm_end && remainder) { 393863551ae0SDavid Gibson pte_t *pte; 3939cb900f41SKirill A. Shutemov spinlock_t *ptl = NULL; 39402a15efc9SHugh Dickins int absent; 394163551ae0SDavid Gibson struct page *page; 394263551ae0SDavid Gibson 39434c887265SAdam Litke /* 394402057967SDavid Rientjes * If we have a pending SIGKILL, don't keep faulting pages and 394502057967SDavid Rientjes * potentially allocating memory. 394602057967SDavid Rientjes */ 394702057967SDavid Rientjes if (unlikely(fatal_signal_pending(current))) { 394802057967SDavid Rientjes remainder = 0; 394902057967SDavid Rientjes break; 395002057967SDavid Rientjes } 395102057967SDavid Rientjes 395202057967SDavid Rientjes /* 39534c887265SAdam Litke * Some archs (sparc64, sh*) have multiple pte_ts to 39542a15efc9SHugh Dickins * each hugepage. We have to make sure we get the 39554c887265SAdam Litke * first, for the page indexing below to work. 3956cb900f41SKirill A. Shutemov * 3957cb900f41SKirill A. Shutemov * Note that page table lock is not held when pte is null. 39584c887265SAdam Litke */ 3959a5516438SAndi Kleen pte = huge_pte_offset(mm, vaddr & huge_page_mask(h)); 3960cb900f41SKirill A. Shutemov if (pte) 3961cb900f41SKirill A. Shutemov ptl = huge_pte_lock(h, mm, pte); 39622a15efc9SHugh Dickins absent = !pte || huge_pte_none(huge_ptep_get(pte)); 396363551ae0SDavid Gibson 39642a15efc9SHugh Dickins /* 39652a15efc9SHugh Dickins * When coredumping, it suits get_dump_page if we just return 39663ae77f43SHugh Dickins * an error where there's an empty slot with no huge pagecache 39673ae77f43SHugh Dickins * to back it. This way, we avoid allocating a hugepage, and 39683ae77f43SHugh Dickins * the sparse dumpfile avoids allocating disk blocks, but its 39693ae77f43SHugh Dickins * huge holes still show up with zeroes where they need to be. 39702a15efc9SHugh Dickins */ 39713ae77f43SHugh Dickins if (absent && (flags & FOLL_DUMP) && 39723ae77f43SHugh Dickins !hugetlbfs_pagecache_present(h, vma, vaddr)) { 3973cb900f41SKirill A. Shutemov if (pte) 3974cb900f41SKirill A. Shutemov spin_unlock(ptl); 39752a15efc9SHugh Dickins remainder = 0; 39762a15efc9SHugh Dickins break; 39772a15efc9SHugh Dickins } 39782a15efc9SHugh Dickins 39799cc3a5bdSNaoya Horiguchi /* 39809cc3a5bdSNaoya Horiguchi * We need call hugetlb_fault for both hugepages under migration 39819cc3a5bdSNaoya Horiguchi * (in which case hugetlb_fault waits for the migration,) and 39829cc3a5bdSNaoya Horiguchi * hwpoisoned hugepages (in which case we need to prevent the 39839cc3a5bdSNaoya Horiguchi * caller from accessing to them.) In order to do this, we use 39849cc3a5bdSNaoya Horiguchi * here is_swap_pte instead of is_hugetlb_entry_migration and 39859cc3a5bdSNaoya Horiguchi * is_hugetlb_entry_hwpoisoned. This is because it simply covers 39869cc3a5bdSNaoya Horiguchi * both cases, and because we can't follow correct pages 39879cc3a5bdSNaoya Horiguchi * directly from any kind of swap entries. 39889cc3a5bdSNaoya Horiguchi */ 39899cc3a5bdSNaoya Horiguchi if (absent || is_swap_pte(huge_ptep_get(pte)) || 3990106c992aSGerald Schaefer ((flags & FOLL_WRITE) && 3991106c992aSGerald Schaefer !huge_pte_write(huge_ptep_get(pte)))) { 39924c887265SAdam Litke int ret; 39934c887265SAdam Litke 3994cb900f41SKirill A. Shutemov if (pte) 3995cb900f41SKirill A. Shutemov spin_unlock(ptl); 39962a15efc9SHugh Dickins ret = hugetlb_fault(mm, vma, vaddr, 39972a15efc9SHugh Dickins (flags & FOLL_WRITE) ? FAULT_FLAG_WRITE : 0); 3998a89182c7SAdam Litke if (!(ret & VM_FAULT_ERROR)) 39994c887265SAdam Litke continue; 40004c887265SAdam Litke 40011c59827dSHugh Dickins remainder = 0; 40021c59827dSHugh Dickins break; 40031c59827dSHugh Dickins } 400463551ae0SDavid Gibson 4005a5516438SAndi Kleen pfn_offset = (vaddr & ~huge_page_mask(h)) >> PAGE_SHIFT; 40067f2e9525SGerald Schaefer page = pte_page(huge_ptep_get(pte)); 4007d5d4b0aaSChen, Kenneth W same_page: 4008d6692183SChen, Kenneth W if (pages) { 400969d177c2SAndy Whitcroft pages[i] = mem_map_offset(page, pfn_offset); 4010ddc58f27SKirill A. Shutemov get_page(pages[i]); 4011d6692183SChen, Kenneth W } 401263551ae0SDavid Gibson 401363551ae0SDavid Gibson if (vmas) 401463551ae0SDavid Gibson vmas[i] = vma; 401563551ae0SDavid Gibson 401663551ae0SDavid Gibson vaddr += PAGE_SIZE; 4017d5d4b0aaSChen, Kenneth W ++pfn_offset; 401863551ae0SDavid Gibson --remainder; 401963551ae0SDavid Gibson ++i; 4020d5d4b0aaSChen, Kenneth W if (vaddr < vma->vm_end && remainder && 4021a5516438SAndi Kleen pfn_offset < pages_per_huge_page(h)) { 4022d5d4b0aaSChen, Kenneth W /* 4023d5d4b0aaSChen, Kenneth W * We use pfn_offset to avoid touching the pageframes 4024d5d4b0aaSChen, Kenneth W * of this compound page. 4025d5d4b0aaSChen, Kenneth W */ 4026d5d4b0aaSChen, Kenneth W goto same_page; 4027d5d4b0aaSChen, Kenneth W } 4028cb900f41SKirill A. Shutemov spin_unlock(ptl); 402963551ae0SDavid Gibson } 403028a35716SMichel Lespinasse *nr_pages = remainder; 403163551ae0SDavid Gibson *position = vaddr; 403263551ae0SDavid Gibson 40332a15efc9SHugh Dickins return i ? i : -EFAULT; 403463551ae0SDavid Gibson } 40358f860591SZhang, Yanmin 40365491ae7bSAneesh Kumar K.V #ifndef __HAVE_ARCH_FLUSH_HUGETLB_TLB_RANGE 40375491ae7bSAneesh Kumar K.V /* 40385491ae7bSAneesh Kumar K.V * ARCHes with special requirements for evicting HUGETLB backing TLB entries can 40395491ae7bSAneesh Kumar K.V * implement this. 40405491ae7bSAneesh Kumar K.V */ 40415491ae7bSAneesh Kumar K.V #define flush_hugetlb_tlb_range(vma, addr, end) flush_tlb_range(vma, addr, end) 40425491ae7bSAneesh Kumar K.V #endif 40435491ae7bSAneesh Kumar K.V 40447da4d641SPeter Zijlstra unsigned long hugetlb_change_protection(struct vm_area_struct *vma, 40458f860591SZhang, Yanmin unsigned long address, unsigned long end, pgprot_t newprot) 40468f860591SZhang, Yanmin { 40478f860591SZhang, Yanmin struct mm_struct *mm = vma->vm_mm; 40488f860591SZhang, Yanmin unsigned long start = address; 40498f860591SZhang, Yanmin pte_t *ptep; 40508f860591SZhang, Yanmin pte_t pte; 4051a5516438SAndi Kleen struct hstate *h = hstate_vma(vma); 40527da4d641SPeter Zijlstra unsigned long pages = 0; 40538f860591SZhang, Yanmin 40548f860591SZhang, Yanmin BUG_ON(address >= end); 40558f860591SZhang, Yanmin flush_cache_range(vma, address, end); 40568f860591SZhang, Yanmin 4057a5338093SRik van Riel mmu_notifier_invalidate_range_start(mm, start, end); 405883cde9e8SDavidlohr Bueso i_mmap_lock_write(vma->vm_file->f_mapping); 4059a5516438SAndi Kleen for (; address < end; address += huge_page_size(h)) { 4060cb900f41SKirill A. Shutemov spinlock_t *ptl; 40618f860591SZhang, Yanmin ptep = huge_pte_offset(mm, address); 40628f860591SZhang, Yanmin if (!ptep) 40638f860591SZhang, Yanmin continue; 4064cb900f41SKirill A. Shutemov ptl = huge_pte_lock(h, mm, ptep); 40657da4d641SPeter Zijlstra if (huge_pmd_unshare(mm, &address, ptep)) { 40667da4d641SPeter Zijlstra pages++; 4067cb900f41SKirill A. Shutemov spin_unlock(ptl); 406839dde65cSChen, Kenneth W continue; 40697da4d641SPeter Zijlstra } 4070a8bda28dSNaoya Horiguchi pte = huge_ptep_get(ptep); 4071a8bda28dSNaoya Horiguchi if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { 4072a8bda28dSNaoya Horiguchi spin_unlock(ptl); 4073a8bda28dSNaoya Horiguchi continue; 4074a8bda28dSNaoya Horiguchi } 4075a8bda28dSNaoya Horiguchi if (unlikely(is_hugetlb_entry_migration(pte))) { 4076a8bda28dSNaoya Horiguchi swp_entry_t entry = pte_to_swp_entry(pte); 4077a8bda28dSNaoya Horiguchi 4078a8bda28dSNaoya Horiguchi if (is_write_migration_entry(entry)) { 4079a8bda28dSNaoya Horiguchi pte_t newpte; 4080a8bda28dSNaoya Horiguchi 4081a8bda28dSNaoya Horiguchi make_migration_entry_read(&entry); 4082a8bda28dSNaoya Horiguchi newpte = swp_entry_to_pte(entry); 4083a8bda28dSNaoya Horiguchi set_huge_pte_at(mm, address, ptep, newpte); 4084a8bda28dSNaoya Horiguchi pages++; 4085a8bda28dSNaoya Horiguchi } 4086a8bda28dSNaoya Horiguchi spin_unlock(ptl); 4087a8bda28dSNaoya Horiguchi continue; 4088a8bda28dSNaoya Horiguchi } 4089a8bda28dSNaoya Horiguchi if (!huge_pte_none(pte)) { 40908f860591SZhang, Yanmin pte = huge_ptep_get_and_clear(mm, address, ptep); 4091106c992aSGerald Schaefer pte = pte_mkhuge(huge_pte_modify(pte, newprot)); 4092be7517d6STony Lu pte = arch_make_huge_pte(pte, vma, NULL, 0); 40938f860591SZhang, Yanmin set_huge_pte_at(mm, address, ptep, pte); 40947da4d641SPeter Zijlstra pages++; 40958f860591SZhang, Yanmin } 4096cb900f41SKirill A. Shutemov spin_unlock(ptl); 40978f860591SZhang, Yanmin } 4098d833352aSMel Gorman /* 4099c8c06efaSDavidlohr Bueso * Must flush TLB before releasing i_mmap_rwsem: x86's huge_pmd_unshare 4100d833352aSMel Gorman * may have cleared our pud entry and done put_page on the page table: 4101c8c06efaSDavidlohr Bueso * once we release i_mmap_rwsem, another task can do the final put_page 4102d833352aSMel Gorman * and that page table be reused and filled with junk. 4103d833352aSMel Gorman */ 41045491ae7bSAneesh Kumar K.V flush_hugetlb_tlb_range(vma, start, end); 410534ee645eSJoerg Roedel mmu_notifier_invalidate_range(mm, start, end); 410683cde9e8SDavidlohr Bueso i_mmap_unlock_write(vma->vm_file->f_mapping); 4107a5338093SRik van Riel mmu_notifier_invalidate_range_end(mm, start, end); 41087da4d641SPeter Zijlstra 41097da4d641SPeter Zijlstra return pages << h->order; 41108f860591SZhang, Yanmin } 41118f860591SZhang, Yanmin 4112a1e78772SMel Gorman int hugetlb_reserve_pages(struct inode *inode, 4113a1e78772SMel Gorman long from, long to, 41145a6fe125SMel Gorman struct vm_area_struct *vma, 4115ca16d140SKOSAKI Motohiro vm_flags_t vm_flags) 4116e4e574b7SAdam Litke { 411717c9d12eSMel Gorman long ret, chg; 4118a5516438SAndi Kleen struct hstate *h = hstate_inode(inode); 411990481622SDavid Gibson struct hugepage_subpool *spool = subpool_inode(inode); 41209119a41eSJoonsoo Kim struct resv_map *resv_map; 41211c5ecae3SMike Kravetz long gbl_reserve; 4122e4e574b7SAdam Litke 4123a1e78772SMel Gorman /* 412417c9d12eSMel Gorman * Only apply hugepage reservation if asked. At fault time, an 412517c9d12eSMel Gorman * attempt will be made for VM_NORESERVE to allocate a page 412690481622SDavid Gibson * without using reserves 412717c9d12eSMel Gorman */ 4128ca16d140SKOSAKI Motohiro if (vm_flags & VM_NORESERVE) 412917c9d12eSMel Gorman return 0; 413017c9d12eSMel Gorman 413117c9d12eSMel Gorman /* 4132a1e78772SMel Gorman * Shared mappings base their reservation on the number of pages that 4133a1e78772SMel Gorman * are already allocated on behalf of the file. Private mappings need 4134a1e78772SMel Gorman * to reserve the full area even if read-only as mprotect() may be 4135a1e78772SMel Gorman * called to make the mapping read-write. Assume !vma is a shm mapping 4136a1e78772SMel Gorman */ 41379119a41eSJoonsoo Kim if (!vma || vma->vm_flags & VM_MAYSHARE) { 41384e35f483SJoonsoo Kim resv_map = inode_resv_map(inode); 41399119a41eSJoonsoo Kim 41401406ec9bSJoonsoo Kim chg = region_chg(resv_map, from, to); 41419119a41eSJoonsoo Kim 41429119a41eSJoonsoo Kim } else { 41439119a41eSJoonsoo Kim resv_map = resv_map_alloc(); 41445a6fe125SMel Gorman if (!resv_map) 41455a6fe125SMel Gorman return -ENOMEM; 41465a6fe125SMel Gorman 414717c9d12eSMel Gorman chg = to - from; 414817c9d12eSMel Gorman 41495a6fe125SMel Gorman set_vma_resv_map(vma, resv_map); 41505a6fe125SMel Gorman set_vma_resv_flags(vma, HPAGE_RESV_OWNER); 41515a6fe125SMel Gorman } 41525a6fe125SMel Gorman 4153c50ac050SDave Hansen if (chg < 0) { 4154c50ac050SDave Hansen ret = chg; 4155c50ac050SDave Hansen goto out_err; 4156c50ac050SDave Hansen } 415717c9d12eSMel Gorman 41581c5ecae3SMike Kravetz /* 41591c5ecae3SMike Kravetz * There must be enough pages in the subpool for the mapping. If 41601c5ecae3SMike Kravetz * the subpool has a minimum size, there may be some global 41611c5ecae3SMike Kravetz * reservations already in place (gbl_reserve). 41621c5ecae3SMike Kravetz */ 41631c5ecae3SMike Kravetz gbl_reserve = hugepage_subpool_get_pages(spool, chg); 41641c5ecae3SMike Kravetz if (gbl_reserve < 0) { 4165c50ac050SDave Hansen ret = -ENOSPC; 4166c50ac050SDave Hansen goto out_err; 4167c50ac050SDave Hansen } 416817c9d12eSMel Gorman 416917c9d12eSMel Gorman /* 417017c9d12eSMel Gorman * Check enough hugepages are available for the reservation. 417190481622SDavid Gibson * Hand the pages back to the subpool if there are not 417217c9d12eSMel Gorman */ 41731c5ecae3SMike Kravetz ret = hugetlb_acct_memory(h, gbl_reserve); 417417c9d12eSMel Gorman if (ret < 0) { 41751c5ecae3SMike Kravetz /* put back original number of pages, chg */ 41761c5ecae3SMike Kravetz (void)hugepage_subpool_put_pages(spool, chg); 4177c50ac050SDave Hansen goto out_err; 417817c9d12eSMel Gorman } 417917c9d12eSMel Gorman 418017c9d12eSMel Gorman /* 418117c9d12eSMel Gorman * Account for the reservations made. Shared mappings record regions 418217c9d12eSMel Gorman * that have reservations as they are shared by multiple VMAs. 418317c9d12eSMel Gorman * When the last VMA disappears, the region map says how much 418417c9d12eSMel Gorman * the reservation was and the page cache tells how much of 418517c9d12eSMel Gorman * the reservation was consumed. Private mappings are per-VMA and 418617c9d12eSMel Gorman * only the consumed reservations are tracked. When the VMA 418717c9d12eSMel Gorman * disappears, the original reservation is the VMA size and the 418817c9d12eSMel Gorman * consumed reservations are stored in the map. Hence, nothing 418917c9d12eSMel Gorman * else has to be done for private mappings here 419017c9d12eSMel Gorman */ 419133039678SMike Kravetz if (!vma || vma->vm_flags & VM_MAYSHARE) { 419233039678SMike Kravetz long add = region_add(resv_map, from, to); 419333039678SMike Kravetz 419433039678SMike Kravetz if (unlikely(chg > add)) { 419533039678SMike Kravetz /* 419633039678SMike Kravetz * pages in this range were added to the reserve 419733039678SMike Kravetz * map between region_chg and region_add. This 419833039678SMike Kravetz * indicates a race with alloc_huge_page. Adjust 419933039678SMike Kravetz * the subpool and reserve counts modified above 420033039678SMike Kravetz * based on the difference. 420133039678SMike Kravetz */ 420233039678SMike Kravetz long rsv_adjust; 420333039678SMike Kravetz 420433039678SMike Kravetz rsv_adjust = hugepage_subpool_put_pages(spool, 420533039678SMike Kravetz chg - add); 420633039678SMike Kravetz hugetlb_acct_memory(h, -rsv_adjust); 420733039678SMike Kravetz } 420833039678SMike Kravetz } 4209a43a8c39SChen, Kenneth W return 0; 4210c50ac050SDave Hansen out_err: 42115e911373SMike Kravetz if (!vma || vma->vm_flags & VM_MAYSHARE) 42125e911373SMike Kravetz region_abort(resv_map, from, to); 4213f031dd27SJoonsoo Kim if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER)) 4214f031dd27SJoonsoo Kim kref_put(&resv_map->refs, resv_map_release); 4215c50ac050SDave Hansen return ret; 4216a43a8c39SChen, Kenneth W } 4217a43a8c39SChen, Kenneth W 4218b5cec28dSMike Kravetz long hugetlb_unreserve_pages(struct inode *inode, long start, long end, 4219b5cec28dSMike Kravetz long freed) 4220a43a8c39SChen, Kenneth W { 4221a5516438SAndi Kleen struct hstate *h = hstate_inode(inode); 42224e35f483SJoonsoo Kim struct resv_map *resv_map = inode_resv_map(inode); 42239119a41eSJoonsoo Kim long chg = 0; 422490481622SDavid Gibson struct hugepage_subpool *spool = subpool_inode(inode); 42251c5ecae3SMike Kravetz long gbl_reserve; 422645c682a6SKen Chen 4227b5cec28dSMike Kravetz if (resv_map) { 4228b5cec28dSMike Kravetz chg = region_del(resv_map, start, end); 4229b5cec28dSMike Kravetz /* 4230b5cec28dSMike Kravetz * region_del() can fail in the rare case where a region 4231b5cec28dSMike Kravetz * must be split and another region descriptor can not be 4232b5cec28dSMike Kravetz * allocated. If end == LONG_MAX, it will not fail. 4233b5cec28dSMike Kravetz */ 4234b5cec28dSMike Kravetz if (chg < 0) 4235b5cec28dSMike Kravetz return chg; 4236b5cec28dSMike Kravetz } 4237b5cec28dSMike Kravetz 423845c682a6SKen Chen spin_lock(&inode->i_lock); 4239e4c6f8beSEric Sandeen inode->i_blocks -= (blocks_per_huge_page(h) * freed); 424045c682a6SKen Chen spin_unlock(&inode->i_lock); 424145c682a6SKen Chen 42421c5ecae3SMike Kravetz /* 42431c5ecae3SMike Kravetz * If the subpool has a minimum size, the number of global 42441c5ecae3SMike Kravetz * reservations to be released may be adjusted. 42451c5ecae3SMike Kravetz */ 42461c5ecae3SMike Kravetz gbl_reserve = hugepage_subpool_put_pages(spool, (chg - freed)); 42471c5ecae3SMike Kravetz hugetlb_acct_memory(h, -gbl_reserve); 4248b5cec28dSMike Kravetz 4249b5cec28dSMike Kravetz return 0; 4250a43a8c39SChen, Kenneth W } 425193f70f90SNaoya Horiguchi 42523212b535SSteve Capper #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE 42533212b535SSteve Capper static unsigned long page_table_shareable(struct vm_area_struct *svma, 42543212b535SSteve Capper struct vm_area_struct *vma, 42553212b535SSteve Capper unsigned long addr, pgoff_t idx) 42563212b535SSteve Capper { 42573212b535SSteve Capper unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) + 42583212b535SSteve Capper svma->vm_start; 42593212b535SSteve Capper unsigned long sbase = saddr & PUD_MASK; 42603212b535SSteve Capper unsigned long s_end = sbase + PUD_SIZE; 42613212b535SSteve Capper 42623212b535SSteve Capper /* Allow segments to share if only one is marked locked */ 4263de60f5f1SEric B Munson unsigned long vm_flags = vma->vm_flags & VM_LOCKED_CLEAR_MASK; 4264de60f5f1SEric B Munson unsigned long svm_flags = svma->vm_flags & VM_LOCKED_CLEAR_MASK; 42653212b535SSteve Capper 42663212b535SSteve Capper /* 42673212b535SSteve Capper * match the virtual addresses, permission and the alignment of the 42683212b535SSteve Capper * page table page. 42693212b535SSteve Capper */ 42703212b535SSteve Capper if (pmd_index(addr) != pmd_index(saddr) || 42713212b535SSteve Capper vm_flags != svm_flags || 42723212b535SSteve Capper sbase < svma->vm_start || svma->vm_end < s_end) 42733212b535SSteve Capper return 0; 42743212b535SSteve Capper 42753212b535SSteve Capper return saddr; 42763212b535SSteve Capper } 42773212b535SSteve Capper 427831aafb45SNicholas Krause static bool vma_shareable(struct vm_area_struct *vma, unsigned long addr) 42793212b535SSteve Capper { 42803212b535SSteve Capper unsigned long base = addr & PUD_MASK; 42813212b535SSteve Capper unsigned long end = base + PUD_SIZE; 42823212b535SSteve Capper 42833212b535SSteve Capper /* 42843212b535SSteve Capper * check on proper vm_flags and page table alignment 42853212b535SSteve Capper */ 42863212b535SSteve Capper if (vma->vm_flags & VM_MAYSHARE && 42873212b535SSteve Capper vma->vm_start <= base && end <= vma->vm_end) 428831aafb45SNicholas Krause return true; 428931aafb45SNicholas Krause return false; 42903212b535SSteve Capper } 42913212b535SSteve Capper 42923212b535SSteve Capper /* 42933212b535SSteve Capper * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() 42943212b535SSteve Capper * and returns the corresponding pte. While this is not necessary for the 42953212b535SSteve Capper * !shared pmd case because we can allocate the pmd later as well, it makes the 42963212b535SSteve Capper * code much cleaner. pmd allocation is essential for the shared case because 4297c8c06efaSDavidlohr Bueso * pud has to be populated inside the same i_mmap_rwsem section - otherwise 42983212b535SSteve Capper * racing tasks could either miss the sharing (see huge_pte_offset) or select a 42993212b535SSteve Capper * bad pmd for sharing. 43003212b535SSteve Capper */ 43013212b535SSteve Capper pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) 43023212b535SSteve Capper { 43033212b535SSteve Capper struct vm_area_struct *vma = find_vma(mm, addr); 43043212b535SSteve Capper struct address_space *mapping = vma->vm_file->f_mapping; 43053212b535SSteve Capper pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + 43063212b535SSteve Capper vma->vm_pgoff; 43073212b535SSteve Capper struct vm_area_struct *svma; 43083212b535SSteve Capper unsigned long saddr; 43093212b535SSteve Capper pte_t *spte = NULL; 43103212b535SSteve Capper pte_t *pte; 4311cb900f41SKirill A. Shutemov spinlock_t *ptl; 43123212b535SSteve Capper 43133212b535SSteve Capper if (!vma_shareable(vma, addr)) 43143212b535SSteve Capper return (pte_t *)pmd_alloc(mm, pud, addr); 43153212b535SSteve Capper 431683cde9e8SDavidlohr Bueso i_mmap_lock_write(mapping); 43173212b535SSteve Capper vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { 43183212b535SSteve Capper if (svma == vma) 43193212b535SSteve Capper continue; 43203212b535SSteve Capper 43213212b535SSteve Capper saddr = page_table_shareable(svma, vma, addr, idx); 43223212b535SSteve Capper if (saddr) { 43233212b535SSteve Capper spte = huge_pte_offset(svma->vm_mm, saddr); 43243212b535SSteve Capper if (spte) { 43253212b535SSteve Capper get_page(virt_to_page(spte)); 43263212b535SSteve Capper break; 43273212b535SSteve Capper } 43283212b535SSteve Capper } 43293212b535SSteve Capper } 43303212b535SSteve Capper 43313212b535SSteve Capper if (!spte) 43323212b535SSteve Capper goto out; 43333212b535SSteve Capper 43348bea8052SAneesh Kumar K.V ptl = huge_pte_lock(hstate_vma(vma), mm, spte); 4335dc6c9a35SKirill A. Shutemov if (pud_none(*pud)) { 43363212b535SSteve Capper pud_populate(mm, pud, 43373212b535SSteve Capper (pmd_t *)((unsigned long)spte & PAGE_MASK)); 4338c17b1f42SKirill A. Shutemov mm_inc_nr_pmds(mm); 4339dc6c9a35SKirill A. Shutemov } else { 43403212b535SSteve Capper put_page(virt_to_page(spte)); 4341dc6c9a35SKirill A. Shutemov } 4342cb900f41SKirill A. Shutemov spin_unlock(ptl); 43433212b535SSteve Capper out: 43443212b535SSteve Capper pte = (pte_t *)pmd_alloc(mm, pud, addr); 434583cde9e8SDavidlohr Bueso i_mmap_unlock_write(mapping); 43463212b535SSteve Capper return pte; 43473212b535SSteve Capper } 43483212b535SSteve Capper 43493212b535SSteve Capper /* 43503212b535SSteve Capper * unmap huge page backed by shared pte. 43513212b535SSteve Capper * 43523212b535SSteve Capper * Hugetlb pte page is ref counted at the time of mapping. If pte is shared 43533212b535SSteve Capper * indicated by page_count > 1, unmap is achieved by clearing pud and 43543212b535SSteve Capper * decrementing the ref count. If count == 1, the pte page is not shared. 43553212b535SSteve Capper * 4356cb900f41SKirill A. Shutemov * called with page table lock held. 43573212b535SSteve Capper * 43583212b535SSteve Capper * returns: 1 successfully unmapped a shared pte page 43593212b535SSteve Capper * 0 the underlying pte page is not shared, or it is the last user 43603212b535SSteve Capper */ 43613212b535SSteve Capper int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) 43623212b535SSteve Capper { 43633212b535SSteve Capper pgd_t *pgd = pgd_offset(mm, *addr); 43643212b535SSteve Capper pud_t *pud = pud_offset(pgd, *addr); 43653212b535SSteve Capper 43663212b535SSteve Capper BUG_ON(page_count(virt_to_page(ptep)) == 0); 43673212b535SSteve Capper if (page_count(virt_to_page(ptep)) == 1) 43683212b535SSteve Capper return 0; 43693212b535SSteve Capper 43703212b535SSteve Capper pud_clear(pud); 43713212b535SSteve Capper put_page(virt_to_page(ptep)); 4372dc6c9a35SKirill A. Shutemov mm_dec_nr_pmds(mm); 43733212b535SSteve Capper *addr = ALIGN(*addr, HPAGE_SIZE * PTRS_PER_PTE) - HPAGE_SIZE; 43743212b535SSteve Capper return 1; 43753212b535SSteve Capper } 43769e5fc74cSSteve Capper #define want_pmd_share() (1) 43779e5fc74cSSteve Capper #else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ 43789e5fc74cSSteve Capper pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) 43799e5fc74cSSteve Capper { 43809e5fc74cSSteve Capper return NULL; 43819e5fc74cSSteve Capper } 4382e81f2d22SZhang Zhen 4383e81f2d22SZhang Zhen int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) 4384e81f2d22SZhang Zhen { 4385e81f2d22SZhang Zhen return 0; 4386e81f2d22SZhang Zhen } 43879e5fc74cSSteve Capper #define want_pmd_share() (0) 43883212b535SSteve Capper #endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ 43893212b535SSteve Capper 43909e5fc74cSSteve Capper #ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB 43919e5fc74cSSteve Capper pte_t *huge_pte_alloc(struct mm_struct *mm, 43929e5fc74cSSteve Capper unsigned long addr, unsigned long sz) 43939e5fc74cSSteve Capper { 43949e5fc74cSSteve Capper pgd_t *pgd; 43959e5fc74cSSteve Capper pud_t *pud; 43969e5fc74cSSteve Capper pte_t *pte = NULL; 43979e5fc74cSSteve Capper 43989e5fc74cSSteve Capper pgd = pgd_offset(mm, addr); 43999e5fc74cSSteve Capper pud = pud_alloc(mm, pgd, addr); 44009e5fc74cSSteve Capper if (pud) { 44019e5fc74cSSteve Capper if (sz == PUD_SIZE) { 44029e5fc74cSSteve Capper pte = (pte_t *)pud; 44039e5fc74cSSteve Capper } else { 44049e5fc74cSSteve Capper BUG_ON(sz != PMD_SIZE); 44059e5fc74cSSteve Capper if (want_pmd_share() && pud_none(*pud)) 44069e5fc74cSSteve Capper pte = huge_pmd_share(mm, addr, pud); 44079e5fc74cSSteve Capper else 44089e5fc74cSSteve Capper pte = (pte_t *)pmd_alloc(mm, pud, addr); 44099e5fc74cSSteve Capper } 44109e5fc74cSSteve Capper } 44114e666314SMichal Hocko BUG_ON(pte && pte_present(*pte) && !pte_huge(*pte)); 44129e5fc74cSSteve Capper 44139e5fc74cSSteve Capper return pte; 44149e5fc74cSSteve Capper } 44159e5fc74cSSteve Capper 44169e5fc74cSSteve Capper pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) 44179e5fc74cSSteve Capper { 44189e5fc74cSSteve Capper pgd_t *pgd; 44199e5fc74cSSteve Capper pud_t *pud; 44209e5fc74cSSteve Capper pmd_t *pmd = NULL; 44219e5fc74cSSteve Capper 44229e5fc74cSSteve Capper pgd = pgd_offset(mm, addr); 44239e5fc74cSSteve Capper if (pgd_present(*pgd)) { 44249e5fc74cSSteve Capper pud = pud_offset(pgd, addr); 44259e5fc74cSSteve Capper if (pud_present(*pud)) { 44269e5fc74cSSteve Capper if (pud_huge(*pud)) 44279e5fc74cSSteve Capper return (pte_t *)pud; 44289e5fc74cSSteve Capper pmd = pmd_offset(pud, addr); 44299e5fc74cSSteve Capper } 44309e5fc74cSSteve Capper } 44319e5fc74cSSteve Capper return (pte_t *) pmd; 44329e5fc74cSSteve Capper } 44339e5fc74cSSteve Capper 443461f77edaSNaoya Horiguchi #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ 443561f77edaSNaoya Horiguchi 443661f77edaSNaoya Horiguchi /* 443761f77edaSNaoya Horiguchi * These functions are overwritable if your architecture needs its own 443861f77edaSNaoya Horiguchi * behavior. 443961f77edaSNaoya Horiguchi */ 444061f77edaSNaoya Horiguchi struct page * __weak 444161f77edaSNaoya Horiguchi follow_huge_addr(struct mm_struct *mm, unsigned long address, 444261f77edaSNaoya Horiguchi int write) 444361f77edaSNaoya Horiguchi { 444461f77edaSNaoya Horiguchi return ERR_PTR(-EINVAL); 444561f77edaSNaoya Horiguchi } 444661f77edaSNaoya Horiguchi 444761f77edaSNaoya Horiguchi struct page * __weak 44489e5fc74cSSteve Capper follow_huge_pmd(struct mm_struct *mm, unsigned long address, 4449e66f17ffSNaoya Horiguchi pmd_t *pmd, int flags) 44509e5fc74cSSteve Capper { 4451e66f17ffSNaoya Horiguchi struct page *page = NULL; 4452e66f17ffSNaoya Horiguchi spinlock_t *ptl; 4453e66f17ffSNaoya Horiguchi retry: 4454e66f17ffSNaoya Horiguchi ptl = pmd_lockptr(mm, pmd); 4455e66f17ffSNaoya Horiguchi spin_lock(ptl); 4456e66f17ffSNaoya Horiguchi /* 4457e66f17ffSNaoya Horiguchi * make sure that the address range covered by this pmd is not 4458e66f17ffSNaoya Horiguchi * unmapped from other threads. 4459e66f17ffSNaoya Horiguchi */ 4460e66f17ffSNaoya Horiguchi if (!pmd_huge(*pmd)) 4461e66f17ffSNaoya Horiguchi goto out; 4462e66f17ffSNaoya Horiguchi if (pmd_present(*pmd)) { 446397534127SGerald Schaefer page = pmd_page(*pmd) + ((address & ~PMD_MASK) >> PAGE_SHIFT); 4464e66f17ffSNaoya Horiguchi if (flags & FOLL_GET) 4465e66f17ffSNaoya Horiguchi get_page(page); 4466e66f17ffSNaoya Horiguchi } else { 4467e66f17ffSNaoya Horiguchi if (is_hugetlb_entry_migration(huge_ptep_get((pte_t *)pmd))) { 4468e66f17ffSNaoya Horiguchi spin_unlock(ptl); 4469e66f17ffSNaoya Horiguchi __migration_entry_wait(mm, (pte_t *)pmd, ptl); 4470e66f17ffSNaoya Horiguchi goto retry; 4471e66f17ffSNaoya Horiguchi } 4472e66f17ffSNaoya Horiguchi /* 4473e66f17ffSNaoya Horiguchi * hwpoisoned entry is treated as no_page_table in 4474e66f17ffSNaoya Horiguchi * follow_page_mask(). 4475e66f17ffSNaoya Horiguchi */ 4476e66f17ffSNaoya Horiguchi } 4477e66f17ffSNaoya Horiguchi out: 4478e66f17ffSNaoya Horiguchi spin_unlock(ptl); 44799e5fc74cSSteve Capper return page; 44809e5fc74cSSteve Capper } 44819e5fc74cSSteve Capper 448261f77edaSNaoya Horiguchi struct page * __weak 44839e5fc74cSSteve Capper follow_huge_pud(struct mm_struct *mm, unsigned long address, 4484e66f17ffSNaoya Horiguchi pud_t *pud, int flags) 44859e5fc74cSSteve Capper { 4486e66f17ffSNaoya Horiguchi if (flags & FOLL_GET) 4487e66f17ffSNaoya Horiguchi return NULL; 44889e5fc74cSSteve Capper 4489e66f17ffSNaoya Horiguchi return pte_page(*(pte_t *)pud) + ((address & ~PUD_MASK) >> PAGE_SHIFT); 44909e5fc74cSSteve Capper } 44919e5fc74cSSteve Capper 4492d5bd9106SAndi Kleen #ifdef CONFIG_MEMORY_FAILURE 4493d5bd9106SAndi Kleen 449493f70f90SNaoya Horiguchi /* 449593f70f90SNaoya Horiguchi * This function is called from memory failure code. 449693f70f90SNaoya Horiguchi */ 44976de2b1aaSNaoya Horiguchi int dequeue_hwpoisoned_huge_page(struct page *hpage) 449893f70f90SNaoya Horiguchi { 449993f70f90SNaoya Horiguchi struct hstate *h = page_hstate(hpage); 450093f70f90SNaoya Horiguchi int nid = page_to_nid(hpage); 45016de2b1aaSNaoya Horiguchi int ret = -EBUSY; 450293f70f90SNaoya Horiguchi 450393f70f90SNaoya Horiguchi spin_lock(&hugetlb_lock); 45047e1f049eSNaoya Horiguchi /* 45057e1f049eSNaoya Horiguchi * Just checking !page_huge_active is not enough, because that could be 45067e1f049eSNaoya Horiguchi * an isolated/hwpoisoned hugepage (which have >0 refcount). 45077e1f049eSNaoya Horiguchi */ 45087e1f049eSNaoya Horiguchi if (!page_huge_active(hpage) && !page_count(hpage)) { 450956f2fb14SNaoya Horiguchi /* 451056f2fb14SNaoya Horiguchi * Hwpoisoned hugepage isn't linked to activelist or freelist, 451156f2fb14SNaoya Horiguchi * but dangling hpage->lru can trigger list-debug warnings 451256f2fb14SNaoya Horiguchi * (this happens when we call unpoison_memory() on it), 451356f2fb14SNaoya Horiguchi * so let it point to itself with list_del_init(). 451456f2fb14SNaoya Horiguchi */ 451556f2fb14SNaoya Horiguchi list_del_init(&hpage->lru); 45168c6c2ecbSNaoya Horiguchi set_page_refcounted(hpage); 451793f70f90SNaoya Horiguchi h->free_huge_pages--; 451893f70f90SNaoya Horiguchi h->free_huge_pages_node[nid]--; 45196de2b1aaSNaoya Horiguchi ret = 0; 452093f70f90SNaoya Horiguchi } 45216de2b1aaSNaoya Horiguchi spin_unlock(&hugetlb_lock); 45226de2b1aaSNaoya Horiguchi return ret; 45236de2b1aaSNaoya Horiguchi } 45246de2b1aaSNaoya Horiguchi #endif 452531caf665SNaoya Horiguchi 452631caf665SNaoya Horiguchi bool isolate_huge_page(struct page *page, struct list_head *list) 452731caf665SNaoya Horiguchi { 4528bcc54222SNaoya Horiguchi bool ret = true; 4529bcc54222SNaoya Horiguchi 4530309381feSSasha Levin VM_BUG_ON_PAGE(!PageHead(page), page); 453131caf665SNaoya Horiguchi spin_lock(&hugetlb_lock); 4532bcc54222SNaoya Horiguchi if (!page_huge_active(page) || !get_page_unless_zero(page)) { 4533bcc54222SNaoya Horiguchi ret = false; 4534bcc54222SNaoya Horiguchi goto unlock; 4535bcc54222SNaoya Horiguchi } 4536bcc54222SNaoya Horiguchi clear_page_huge_active(page); 453731caf665SNaoya Horiguchi list_move_tail(&page->lru, list); 4538bcc54222SNaoya Horiguchi unlock: 453931caf665SNaoya Horiguchi spin_unlock(&hugetlb_lock); 4540bcc54222SNaoya Horiguchi return ret; 454131caf665SNaoya Horiguchi } 454231caf665SNaoya Horiguchi 454331caf665SNaoya Horiguchi void putback_active_hugepage(struct page *page) 454431caf665SNaoya Horiguchi { 4545309381feSSasha Levin VM_BUG_ON_PAGE(!PageHead(page), page); 454631caf665SNaoya Horiguchi spin_lock(&hugetlb_lock); 4547bcc54222SNaoya Horiguchi set_page_huge_active(page); 454831caf665SNaoya Horiguchi list_move_tail(&page->lru, &(page_hstate(page))->hugepage_activelist); 454931caf665SNaoya Horiguchi spin_unlock(&hugetlb_lock); 455031caf665SNaoya Horiguchi put_page(page); 455131caf665SNaoya Horiguchi } 4552