diff options
Diffstat (limited to 'mm/shmem.c')
| -rw-r--r-- | mm/shmem.c | 934 |
1 files changed, 833 insertions, 101 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index 24463b67b6ef..2ac19a61d565 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -32,6 +32,7 @@ #include <linux/export.h> #include <linux/swap.h> #include <linux/uio.h> +#include <linux/khugepaged.h> static struct vfsmount *shm_mnt; @@ -97,14 +98,6 @@ struct shmem_falloc { pgoff_t nr_unswapped; /* how often writepage refused to swap out */ }; -/* Flag allocation requirements to shmem_getpage */ -enum sgp_type { - SGP_READ, /* don't exceed i_size, don't allocate page */ - SGP_CACHE, /* don't exceed i_size, may allocate page */ - SGP_WRITE, /* may exceed i_size, may allocate !Uptodate page */ - SGP_FALLOC, /* like SGP_WRITE, but make existing page Uptodate */ -}; - #ifdef CONFIG_TMPFS static unsigned long shmem_default_max_blocks(void) { @@ -124,7 +117,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index, struct page **pagep, enum sgp_type sgp, gfp_t gfp, struct mm_struct *fault_mm, int *fault_type); -static inline int shmem_getpage(struct inode *inode, pgoff_t index, +int shmem_getpage(struct inode *inode, pgoff_t index, struct page **pagep, enum sgp_type sgp) { return shmem_getpage_gfp(inode, index, pagep, sgp, @@ -173,10 +166,13 @@ static inline int shmem_reacct_size(unsigned long flags, * shmem_getpage reports shmem_acct_block failure as -ENOSPC not -ENOMEM, * so that a failure on a sparse tmpfs mapping will give SIGBUS not OOM. */ -static inline int shmem_acct_block(unsigned long flags) +static inline int shmem_acct_block(unsigned long flags, long pages) { - return (flags & VM_NORESERVE) ? - security_vm_enough_memory_mm(current->mm, VM_ACCT(PAGE_SIZE)) : 0; + if (!(flags & VM_NORESERVE)) + return 0; + + return security_vm_enough_memory_mm(current->mm, + pages * VM_ACCT(PAGE_SIZE)); } static inline void shmem_unacct_blocks(unsigned long flags, long pages) @@ -192,6 +188,7 @@ static const struct inode_operations shmem_inode_operations; static const struct inode_operations shmem_dir_inode_operations; static const struct inode_operations shmem_special_inode_operations; static const struct vm_operations_struct shmem_vm_ops; +static struct file_system_type shmem_fs_type; static LIST_HEAD(shmem_swaplist); static DEFINE_MUTEX(shmem_swaplist_mutex); @@ -249,6 +246,53 @@ static void shmem_recalc_inode(struct inode *inode) } } +bool shmem_charge(struct inode *inode, long pages) +{ + struct shmem_inode_info *info = SHMEM_I(inode); + struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb); + unsigned long flags; + + if (shmem_acct_block(info->flags, pages)) + return false; + spin_lock_irqsave(&info->lock, flags); + info->alloced += pages; + inode->i_blocks += pages * BLOCKS_PER_PAGE; + shmem_recalc_inode(inode); + spin_unlock_irqrestore(&info->lock, flags); + inode->i_mapping->nrpages += pages; + + if (!sbinfo->max_blocks) + return true; + if (percpu_counter_compare(&sbinfo->used_blocks, + sbinfo->max_blocks - pages) > 0) { + inode->i_mapping->nrpages -= pages; + spin_lock_irqsave(&info->lock, flags); + info->alloced -= pages; + shmem_recalc_inode(inode); + spin_unlock_irqrestore(&info->lock, flags); + + return false; + } + percpu_counter_add(&sbinfo->used_blocks, pages); + return true; +} + +void shmem_uncharge(struct inode *inode, long pages) +{ + struct shmem_inode_info *info = SHMEM_I(inode); + struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb); + unsigned long flags; + + spin_lock_irqsave(&info->lock, flags); + info->alloced -= pages; + inode->i_blocks -= pages * BLOCKS_PER_PAGE; + shmem_recalc_inode(inode); + spin_unlock_irqrestore(&info->lock, flags); + + if (sbinfo->max_blocks) + percpu_counter_sub(&sbinfo->used_blocks, pages); +} + /* * Replace item expected in radix tree by a new item, while holding tree lock. */ @@ -289,36 +333,256 @@ static bool shmem_confirm_swap(struct address_space *mapping, } /* + * Definitions for "huge tmpfs": tmpfs mounted with the huge= option + * + * SHMEM_HUGE_NEVER: + * disables huge pages for the mount; + * SHMEM_HUGE_ALWAYS: + * enables huge pages for the mount; + * SHMEM_HUGE_WITHIN_SIZE: + * only allocate huge pages if the page will be fully within i_size, + * also respect fadvise()/madvise() hints; + * SHMEM_HUGE_ADVISE: + * only allocate huge pages if requested with fadvise()/madvise(); + */ + +#define SHMEM_HUGE_NEVER 0 +#define SHMEM_HUGE_ALWAYS 1 +#define SHMEM_HUGE_WITHIN_SIZE 2 +#define SHMEM_HUGE_ADVISE 3 + +/* + * Special values. + * Only can be set via /sys/kernel/mm/transparent_hugepage/shmem_enabled: + * + * SHMEM_HUGE_DENY: + * disables huge on shm_mnt and all mounts, for emergency use; + * SHMEM_HUGE_FORCE: + * enables huge on shm_mnt and all mounts, w/o needing option, for testing; + * + */ +#define SHMEM_HUGE_DENY (-1) +#define SHMEM_HUGE_FORCE (-2) + +#ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE +/* ifdef here to avoid bloating shmem.o when not necessary */ + +int shmem_huge __read_mostly; + +static int shmem_parse_huge(const char *str) +{ + if (!strcmp(str, "never")) + return SHMEM_HUGE_NEVER; + if (!strcmp(str, "always")) + return SHMEM_HUGE_ALWAYS; + if (!strcmp(str, "within_size")) + return SHMEM_HUGE_WITHIN_SIZE; + if (!strcmp(str, "advise")) + return SHMEM_HUGE_ADVISE; + if (!strcmp(str, "deny")) + return SHMEM_HUGE_DENY; + if (!strcmp(str, "force")) + return SHMEM_HUGE_FORCE; + return -EINVAL; +} + +static const char *shmem_format_huge(int huge) +{ + switch (huge) { + case SHMEM_HUGE_NEVER: + return "never"; + case SHMEM_HUGE_ALWAYS: + return "always"; + case SHMEM_HUGE_WITHIN_SIZE: + return "within_size"; + case SHMEM_HUGE_ADVISE: + return "advise"; + case SHMEM_HUGE_DENY: + return "deny"; + case SHMEM_HUGE_FORCE: + return "force"; + default: + VM_BUG_ON(1); + return "bad_val"; + } +} + +static unsigned long shmem_unused_huge_shrink(struct shmem_sb_info *sbinfo, + struct shrink_control *sc, unsigned long nr_to_split) +{ + LIST_HEAD(list), *pos, *next; + struct inode *inode; + struct shmem_inode_info *info; + struct page *page; + unsigned long batch = sc ? sc->nr_to_scan : 128; + int removed = 0, split = 0; + + if (list_empty(&sbinfo->shrinklist)) + return SHRINK_STOP; + + spin_lock(&sbinfo->shrinklist_lock); + list_for_each_safe(pos, next, &sbinfo->shrinklist) { + info = list_entry(pos, struct shmem_inode_info, shrinklist); + + /* pin the inode */ + inode = igrab(&info->vfs_inode); + + /* inode is about to be evicted */ + if (!inode) { + list_del_init(&info->shrinklist); + removed++; + goto next; + } + + /* Check if there's anything to gain */ + if (round_up(inode->i_size, PAGE_SIZE) == + round_up(inode->i_size, HPAGE_PMD_SIZE)) { + list_del_init(&info->shrinklist); + removed++; + iput(inode); + goto next; + } + + list_move(&info->shrinklist, &list); +next: + if (!--batch) + break; + } + spin_unlock(&sbinfo->shrinklist_lock); + + list_for_each_safe(pos, next, &list) { + int ret; + + info = list_entry(pos, struct shmem_inode_info, shrinklist); + inode = &info->vfs_inode; + + if (nr_to_split && split >= nr_to_split) { + iput(inode); + continue; + } + + page = find_lock_page(inode->i_mapping, + (inode->i_size & HPAGE_PMD_MASK) >> PAGE_SHIFT); + if (!page) + goto drop; + + if (!PageTransHuge(page)) { + unlock_page(page); + put_page(page); + goto drop; + } + + ret = split_huge_page(page); + unlock_page(page); + put_page(page); + + if (ret) { + /* split failed: leave it on the list */ + iput(inode); + continue; + } + + split++; +drop: + list_del_init(&info->shrinklist); + removed++; + iput(inode); + } + + spin_lock(&sbinfo->shrinklist_lock); + list_splice_tail(&list, &sbinfo->shrinklist); + sbinfo->shrinklist_len -= removed; + spin_unlock(&sbinfo->shrinklist_lock); + + return split; +} + +static long shmem_unused_huge_scan(struct super_block *sb, + struct shrink_control *sc) +{ + struct shmem_sb_info *sbinfo = SHMEM_SB(sb); + + if (!READ_ONCE(sbinfo->shrinklist_len)) + return SHRINK_STOP; + + return shmem_unused_huge_shrink(sbinfo, sc, 0); +} + +static long shmem_unused_huge_count(struct super_block *sb, + struct shrink_control *sc) +{ + struct shmem_sb_info *sbinfo = SHMEM_SB(sb); + return READ_ONCE(sbinfo->shrinklist_len); +} +#else /* !CONFIG_TRANSPARENT_HUGE_PAGECACHE */ + +#define shmem_huge SHMEM_HUGE_DENY + +static unsigned long shmem_unused_huge_shrink(struct shmem_sb_info *sbinfo, + struct shrink_control *sc, unsigned long nr_to_split) +{ + return 0; +} +#endif /* CONFIG_TRANSPARENT_HUGE_PAGECACHE */ + +/* * Like add_to_page_cache_locked, but error if expected item has gone. */ static int shmem_add_to_page_cache(struct page *page, struct address_space *mapping, pgoff_t index, void *expected) { - int error; + int error, nr = hpage_nr_pages(page); + VM_BUG_ON_PAGE(PageTail(page), page); + VM_BUG_ON_PAGE(index != round_down(index, nr), page); VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(!PageSwapBacked(page), page); + VM_BUG_ON(expected && PageTransHuge(page)); - get_page(page); + page_ref_add(page, nr); page->mapping = mapping; page->index = index; spin_lock_irq(&mapping->tree_lock); - if (!expected) + if (PageTransHuge(page)) { + void __rcu **results; + pgoff_t idx; + int i; + + error = 0; + if (radix_tree_gang_lookup_slot(&mapping->page_tree, + &results, &idx, index, 1) && + idx < index + HPAGE_PMD_NR) { + error = -EEXIST; + } + + if (!error) { + for (i = 0; i < HPAGE_PMD_NR; i++) { + error = radix_tree_insert(&mapping->page_tree, + index + i, page + i); + VM_BUG_ON(error); + } + count_vm_event(THP_FILE_ALLOC); + } + } else if (!expected) { error = radix_tree_insert(&mapping->page_tree, index, page); - else + } else { error = shmem_radix_tree_replace(mapping, index, expected, page); + } + if (!error) { - mapping->nrpages++; - __inc_zone_page_state(page, NR_FILE_PAGES); - __inc_zone_page_state(page, NR_SHMEM); + mapping->nrpages += nr; + if (PageTransHuge(page)) + __inc_node_page_state(page, NR_SHMEM_THPS); + __mod_node_page_state(page_pgdat(page), NR_FILE_PAGES, nr); + __mod_node_page_state(page_pgdat(page), NR_SHMEM, nr); spin_unlock_irq(&mapping->tree_lock); } else { page->mapping = NULL; spin_unlock_irq(&mapping->tree_lock); - put_page(page); + page_ref_sub(page, nr); } return error; } @@ -331,12 +595,14 @@ static void shmem_delete_from_page_cache(struct page *page, void *radswap) struct address_space *mapping = page->mapping; int error; + VM_BUG_ON_PAGE(PageCompound(page), page); + spin_lock_irq(&mapping->tree_lock); error = shmem_radix_tree_replace(mapping, page->index, page, radswap); page->mapping = NULL; mapping->nrpages--; - __dec_zone_page_state(page, NR_FILE_PAGES); - __dec_zone_page_state(page, NR_SHMEM); + __dec_node_page_state(page, NR_FILE_PAGES); + __dec_node_page_state(page, NR_SHMEM); spin_unlock_irq(&mapping->tree_lock); put_page(page); BUG_ON(error); @@ -510,10 +776,33 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, continue; } + VM_BUG_ON_PAGE(page_to_pgoff(page) != index, page); + if (!trylock_page(page)) continue; + + if (PageTransTail(page)) { + /* Middle of THP: zero out the page */ + clear_highpage(page); + unlock_page(page); + continue; + } else if (PageTransHuge(page)) { + if (index == round_down(end, HPAGE_PMD_NR)) { + /* + * Range ends in the middle of THP: + * zero out the page + */ + clear_highpage(page); + unlock_page(page); + continue; + } + index += HPAGE_PMD_NR - 1; + i += HPAGE_PMD_NR - 1; + } + if (!unfalloc || !PageUptodate(page)) { - if (page->mapping == mapping) { + VM_BUG_ON_PAGE(PageTail(page), page); + if (page_mapping(page) == mapping) { VM_BUG_ON_PAGE(PageWriteback(page), page); truncate_inode_page(mapping, page); } @@ -589,8 +878,36 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, } lock_page(page); + + if (PageTransTail(page)) { + /* Middle of THP: zero out the page */ + clear_highpage(page); + unlock_page(page); + /* + * Partial thp truncate due 'start' in middle + * of THP: don't need to look on these pages + * again on !pvec.nr restart. + */ + if (index != round_down(end, HPAGE_PMD_NR)) + start++; + continue; + } else if (PageTransHuge(page)) { + if (index == round_down(end, HPAGE_PMD_NR)) { + /* + * Range ends in the middle of THP: + * zero out the page + */ + clear_highpage(page); + unlock_page(page); + continue; + } + index += HPAGE_PMD_NR - 1; + i += HPAGE_PMD_NR - 1; + } + if (!unfalloc || !PageUptodate(page)) { - if (page->mapping == mapping) { + VM_BUG_ON_PAGE(PageTail(page), page); + if (page_mapping(page) == mapping) { VM_BUG_ON_PAGE(PageWriteback(page), page); truncate_inode_page(mapping, page); } else { @@ -607,10 +924,10 @@ static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend, index++; } - spin_lock(&info->lock); + spin_lock_irq(&info->lock); info->swapped -= nr_swaps_freed; shmem_recalc_inode(inode); - spin_unlock(&info->lock); + spin_unlock_irq(&info->lock); } void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) @@ -627,9 +944,9 @@ static int shmem_getattr(struct vfsmount *mnt, struct dentry *dentry, struct shmem_inode_info *info = SHMEM_I(inode); if (info->alloced - info->swapped != inode->i_mapping->nrpages) { - spin_lock(&info->lock); + spin_lock_irq(&info->lock); shmem_recalc_inode(inode); - spin_unlock(&info->lock); + spin_unlock_irq(&info->lock); } generic_fillattr(inode, stat); return 0; @@ -639,6 +956,7 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr) { struct inode *inode = d_inode(dentry); struct shmem_inode_info *info = SHMEM_I(inode); + struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb); int error; error = inode_change_ok(inode, attr); @@ -674,6 +992,20 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr) if (oldsize > holebegin) unmap_mapping_range(inode->i_mapping, holebegin, 0, 1); + + /* + * Part of the huge page can be beyond i_size: subject + * to shrink under memory pressure. + */ + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE)) { + spin_lock(&sbinfo->shrinklist_lock); + if (list_empty(&info->shrinklist)) { + list_add_tail(&info->shrinklist, + &sbinfo->shrinklist); + sbinfo->shrinklist_len++; + } + spin_unlock(&sbinfo->shrinklist_lock); + } } } @@ -686,11 +1018,20 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr) static void shmem_evict_inode(struct inode *inode) { struct shmem_inode_info *info = SHMEM_I(inode); + struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb); if (inode->i_mapping->a_ops == &shmem_aops) { shmem_unacct_size(info->flags, inode->i_size); inode->i_size = 0; shmem_truncate_range(inode, 0, (loff_t)-1); + if (!list_empty(&info->shrinklist)) { + spin_lock(&sbinfo->shrinklist_lock); + if (!list_empty(&info->shrinklist)) { + list_del_init(&info->shrinklist); + sbinfo->shrinklist_len--; + } + spin_unlock(&sbinfo->shrinklist_lock); + } if (!list_empty(&info->swaplist)) { mutex_lock(&shmem_swaplist_mutex); list_del_init(&info->swaplist); @@ -773,9 +1114,9 @@ static int shmem_unuse_inode(struct shmem_inode_info *info, delete_from_swap_cache(*pagep); set_page_dirty(*pagep); if (!error) { - spin_lock(&info->lock); + spin_lock_irq(&info->lock); info->swapped--; - spin_unlock(&info->lock); + spin_unlock_irq(&info->lock); swap_free(swap); } } @@ -848,6 +1189,7 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc) swp_entry_t swap; pgoff_t index; + VM_BUG_ON_PAGE(PageCompound(page), page); BUG_ON(!PageLocked(page)); mapping = page->mapping; index = page->index; @@ -922,10 +1264,10 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc) list_add_tail(&info->swaplist, &shmem_swaplist); if (add_to_swap_cache(page, swap, GFP_ATOMIC) == 0) { - spin_lock(&info->lock); + spin_lock_irq(&info->lock); shmem_recalc_inode(inode); info->swapped++; - spin_unlock(&info->lock); + spin_unlock_irq(&info->lock); swap_shmem_alloc(swap); shmem_delete_from_page_cache(page, swp_to_radix_entry(swap)); @@ -984,24 +1326,63 @@ static inline struct mempolicy *shmem_get_sbmpol(struct shmem_sb_info *sbinfo) #define vm_policy vm_private_data #endif +static void shmem_pseudo_vma_init(struct vm_area_struct *vma, + struct shmem_inode_info *info, pgoff_t index) +{ + /* Create a pseudo vma that just contains the policy */ + vma->vm_start = 0; + /* Bias interleave by inode number to distribute better across nodes */ + vma->vm_pgoff = index + info->vfs_inode.i_ino; + vma->vm_ops = NULL; + vma->vm_policy = mpol_shared_policy_lookup(&info->policy, index); +} + +static void shmem_pseudo_vma_destroy(struct vm_area_struct *vma) +{ + /* Drop reference taken by mpol_shared_policy_lookup() */ + mpol_cond_put(vma->vm_policy); +} + static struct page *shmem_swapin(swp_entry_t swap, gfp_t gfp, struct shmem_inode_info *info, pgoff_t index) { struct vm_area_struct pvma; struct page *page; - /* Create a pseudo vma that just contains the policy */ - pvma.vm_start = 0; - /* Bias interleave by inode number to distribute better across nodes */ - pvma.vm_pgoff = index + info->vfs_inode.i_ino; - pvma.vm_ops = NULL; - pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, index); - + shmem_pseudo_vma_init(&pvma, info, index); page = swapin_readahead(swap, gfp, &pvma, 0); + shmem_pseudo_vma_destroy(&pvma); - /* Drop reference taken by mpol_shared_policy_lookup() */ - mpol_cond_put(pvma.vm_policy); + return page; +} +static struct page *shmem_alloc_hugepage(gfp_t gfp, + struct shmem_inode_info *info, pgoff_t index) +{ + struct vm_area_struct pvma; + struct inode *inode = &info->vfs_inode; + struct address_space *mapping = inode->i_mapping; + pgoff_t idx, hindex = round_down(index, HPAGE_PMD_NR); + void __rcu **results; + struct page *page; + + if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE)) + return NULL; + + rcu_read_lock(); + if (radix_tree_gang_lookup_slot(&mapping->page_tree, &results, &idx, + hindex, 1) && idx < hindex + HPAGE_PMD_NR) { + rcu_read_unlock(); + return NULL; + } + rcu_read_unlock(); + + shmem_pseudo_vma_init(&pvma, info, hindex); + page = alloc_pages_vma(gfp | __GFP_COMP | __GFP_NORETRY | __GFP_NOWARN, + HPAGE_PMD_ORDER, &pvma, 0, numa_node_id(), true); + shmem_pseudo_vma_destroy(&pvma); + if (page) + prep_transhuge_page(page); return page; } @@ -1011,23 +1392,51 @@ static struct page *shmem_alloc_page(gfp_t gfp, struct vm_area_struct pvma; struct page *page; - /* Create a pseudo vma that just contains the policy */ - pvma.vm_start = 0; - /* Bias interleave by inode number to distribute better across nodes */ - pvma.vm_pgoff = index + info->vfs_inode.i_ino; - pvma.vm_ops = NULL; - pvma.vm_policy = mpol_shared_policy_lookup(&info->policy, index); + shmem_pseudo_vma_init(&pvma, info, index); + page = alloc_page_vma(gfp, &pvma, 0); + shmem_pseudo_vma_destroy(&pvma); - page = alloc_pages_vma(gfp, 0, &pvma, 0, numa_node_id(), false); + return page; +} + +static struct page *shmem_alloc_and_acct_page(gfp_t gfp, + struct shmem_inode_info *info, struct shmem_sb_info *sbinfo, + pgoff_t index, bool huge) +{ + struct page *page; + int nr; + int err = -ENOSPC; + + if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE)) + huge = false; + nr = huge ? HPAGE_PMD_NR : 1; + + if (shmem_acct_block(info->flags, nr)) + goto failed; + if (sbinfo->max_blocks) { + if (percpu_counter_compare(&sbinfo->used_blocks, + sbinfo->max_blocks - nr) > 0) + goto unacct; + percpu_counter_add(&sbinfo->used_blocks, nr); + } + + if (huge) + page = shmem_alloc_hugepage(gfp, info, index); + else + page = shmem_alloc_page(gfp, info, index); if (page) { __SetPageLocked(page); __SetPageSwapBacked(page); + return page; } - /* Drop reference taken by mpol_shared_policy_lookup() */ - mpol_cond_put(pvma.vm_policy); - - return page; + err = -ENOMEM; + if (sbinfo->max_blocks) + percpu_counter_add(&sbinfo->used_blocks, -nr); +unacct: + shmem_unacct_blocks(info->flags, nr); +failed: + return ERR_PTR(err); } /* @@ -1084,8 +1493,8 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp, error = shmem_radix_tree_replace(swap_mapping, swap_index, oldpage, newpage); if (!error) { - __inc_zone_page_state(newpage, NR_FILE_PAGES); - __dec_zone_page_state(oldpage, NR_FILE_PAGES); + __inc_node_page_state(newpage, NR_FILE_PAGES); + __dec_node_page_state(oldpage, NR_FILE_PAGES); } spin_unlock_irq(&swap_mapping->tree_lock); @@ -1132,12 +1541,16 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index, struct mem_cgroup *memcg; struct page *page; swp_entry_t swap; + enum sgp_type sgp_huge = sgp; + pgoff_t hindex = index; int error; int once = 0; int alloced = 0; if (index > (MAX_LFS_FILESIZE >> PAGE_SHIFT)) return -EFBIG; + if (sgp == SGP_NOHUGE || sgp == SGP_HUGE) + sgp = SGP_CACHE; repeat: swap.val = 0; page = find_lock_entry(mapping, index); @@ -1240,10 +1653,10 @@ repeat: mem_cgroup_commit_charge(page, memcg, true, false); - spin_lock(&info->lock); + spin_lock_irq(&info->lock); info->swapped--; shmem_recalc_inode(inode); - spin_unlock(&info->lock); + spin_unlock_irq(&info->lock); if (sgp == SGP_WRITE) mark_page_accessed(page); @@ -1253,51 +1666,111 @@ repeat: swap_free(swap); } else { - if (shmem_acct_block(info->flags)) { - error = -ENOSPC; - goto failed; + /* shmem_symlink() */ + if (mapping->a_ops != &shmem_aops) + goto alloc_nohuge; + if (shmem_huge == SHMEM_HUGE_DENY || sgp_huge == SGP_NOHUGE) + goto alloc_nohuge; + if (shmem_huge == SHMEM_HUGE_FORCE) + goto alloc_huge; + switch (sbinfo->huge) { + loff_t i_size; + pgoff_t off; + case SHMEM_HUGE_NEVER: + goto alloc_nohuge; + case SHMEM_HUGE_WITHIN_SIZE: + off = round_up(index, HPAGE_PMD_NR); + i_size = round_up(i_size_read(inode), PAGE_SIZE); + if (i_size >= HPAGE_PMD_SIZE && + i_size >> PAGE_SHIFT >= off) + goto alloc_huge; + /* fallthrough */ + case SHMEM_HUGE_ADVISE: + if (sgp_huge == SGP_HUGE) + goto alloc_huge; + /* TODO: implement fadvise() hints */ + goto alloc_nohuge; + } + +alloc_huge: + page = shmem_alloc_and_acct_page(gfp, info, sbinfo, + index, true); + if (IS_ERR(page)) { +alloc_nohuge: page = shmem_alloc_and_acct_page(gfp, info, sbinfo, + index, false); } - if (sbinfo->max_blocks) { - if (percpu_counter_compare(&sbinfo->used_blocks, - sbinfo->max_blocks) >= 0) { - error = -ENOSPC; - goto unacct; + if (IS_ERR(page)) { + int retry = 5; + error = PTR_ERR(page); + page = NULL; + if (error != -ENOSPC) + goto failed; + /* + * Try to reclaim some spece by splitting a huge page + * beyond i_size on the filesystem. + */ + while (retry--) { + int ret; + ret = shmem_unused_huge_shrink(sbinfo, NULL, 1); + if (ret == SHRINK_STOP) + break; + if (ret) + goto alloc_nohuge; } - percpu_counter_inc(&sbinfo->used_blocks); + goto failed; } - page = shmem_alloc_page(gfp, info, index); - if (!page) { - error = -ENOMEM; - goto decused; - } + if (PageTransHuge(page)) + hindex = round_down(index, HPAGE_PMD_NR); + else + hindex = index; + if (sgp == SGP_WRITE) __SetPageReferenced(page); error = mem_cgroup_try_charge(page, charge_mm, gfp, &memcg, - false); + PageTransHuge(page)); if (error) - goto decused; - error = radix_tree_maybe_preload(gfp & GFP_RECLAIM_MASK); + goto unacct; + error = radix_tree_maybe_preload_order(gfp & GFP_RECLAIM_MASK, + compound_order(page)); if (!error) { - error = shmem_add_to_page_cache(page, mapping, index, + error = shmem_add_to_page_cache(page, mapping, hindex, NULL); radix_tree_preload_end(); } if (error) { - mem_cgroup_cancel_charge(page, memcg, false); - goto decused; + mem_cgroup_cancel_charge(page, memcg, + PageTransHuge(page)); + goto unacct; } - mem_cgroup_commit_charge(page, memcg, false, false); + mem_cgroup_commit_charge(page, memcg, false, + PageTransHuge(page)); lru_cache_add_anon(page); - spin_lock(&info->lock); - info->alloced++; - inode->i_blocks += BLOCKS_PER_PAGE; + spin_lock_irq(&info->lock); + info->alloced += 1 << compound_order(page); + inode->i_blocks += BLOCKS_PER_PAGE << compound_order(page); shmem_recalc_inode(inode); - spin_unlock(&info->lock); + spin_unlock_irq(&info->lock); alloced = true; + if (PageTransHuge(page) && + DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE) < + hindex + HPAGE_PMD_NR - 1) { + /* + * Part of the huge page is beyond i_size: subject + * to shrink under memory pressure. + */ + spin_lock(&sbinfo->shrinklist_lock); + if (list_empty(&info->shrinklist)) { + list_add_tail(&info->shrinklist, + &sbinfo->shrinklist); + sbinfo->shrinklist_len++; + } + spin_unlock(&sbinfo->shrinklist_lock); + } + /* * Let SGP_FALLOC use the SGP_WRITE optimization on a new page. */ @@ -1309,10 +1782,15 @@ clear: * but SGP_FALLOC on a page fallocated earlier must initialize * it now, lest undo on failure cancel our earlier guarantee. */ - if (sgp != SGP_WRITE) { - clear_highpage(page); - flush_dcache_page(page); - SetPageUptodate(page); + if (sgp != SGP_WRITE && !PageUptodate(page)) { + struct page *head = compound_head(page); + int i; + + for (i = 0; i < (1 << compound_order(head)); i++) { + clear_highpage(head + i); + flush_dcache_page(head + i); + } + SetPageUptodate(head); } } @@ -1322,24 +1800,30 @@ clear: if (alloced) { ClearPageDirty(page); delete_from_page_cache(page); - spin_lock(&info->lock); + spin_lock_irq(&info->lock); shmem_recalc_inode(inode); - spin_unlock(&info->lock); + spin_unlock_irq(&info->lock); } error = -EINVAL; goto unlock; } - *pagep = page; + *pagep = page + index - hindex; return 0; /* * Error recovery. */ -decused: - if (sbinfo->max_blocks) - percpu_counter_add(&sbinfo->used_blocks, -1); unacct: - shmem_unacct_blocks(info->flags, 1); + if (sbinfo->max_blocks) + percpu_counter_sub(&sbinfo->used_blocks, + 1 << compound_order(page)); + shmem_unacct_blocks(info->flags, 1 << compound_order(page)); + + if (PageTransHuge(page)) { + unlock_page(page); + put_page(page); + goto alloc_nohuge; + } failed: if (swap.val && !shmem_confirm_swap(mapping, index, swap)) error = -EEXIST; @@ -1350,9 +1834,9 @@ unlock: } if (error == -ENOSPC && !once++) { info = SHMEM_I(inode); - spin_lock(&info->lock); + spin_lock_irq(&info->lock); shmem_recalc_inode(inode); - spin_unlock(&info->lock); + spin_unlock_irq(&info->lock); goto repeat; } if (error == -EEXIST) /* from above or from radix_tree_insert */ @@ -1364,6 +1848,7 @@ static int shmem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { struct inode *inode = file_inode(vma->vm_file); gfp_t gfp = mapping_gfp_mask(inode->i_mapping); + enum sgp_type sgp; int error; int ret = VM_FAULT_LOCKED; @@ -1425,13 +1910,107 @@ static int shmem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) spin_unlock(&inode->i_lock); } - error = shmem_getpage_gfp(inode, vmf->pgoff, &vmf->page, SGP_CACHE, + sgp = SGP_CACHE; + if (vma->vm_flags & VM_HUGEPAGE) + sgp = SGP_HUGE; + else if (vma->vm_flags & VM_NOHUGEPAGE) + sgp = SGP_NOHUGE; + + error = shmem_getpage_gfp(inode, vmf->pgoff, &vmf->page, sgp, gfp, vma->vm_mm, &ret); if (error) return ((error == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS); return ret; } +unsigned long shmem_get_unmapped_area(struct file *file, + unsigned long uaddr, unsigned long len, + unsigned long pgoff, unsigned long flags) +{ + unsigned long (*get_area)(struct file *, + unsigned long, unsigned long, unsigned long, unsigned long); + unsigned long addr; + unsigned long offset; + unsigned long inflated_len; + unsigned long inflated_addr; + unsigned long inflated_offset; + + if (len > TASK_SIZE) + return -ENOMEM; + + get_area = current->mm->get_unmapped_area; + addr = get_area(file, uaddr, len, pgoff, flags); + + if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE)) + return addr; + if (IS_ERR_VALUE(addr)) + return addr; + if (addr & ~PAGE_MASK) + return addr; + if (addr > TASK_SIZE - len) + return addr; + + if (shmem_huge == SHMEM_HUGE_DENY) + return addr; + if (len < HPAGE_PMD_SIZE) + return addr; + if (flags & MAP_FIXED) + return addr; + /* + * Our priority is to support MAP_SHARED mapped hugely; + * and support MAP_PRIVATE mapped hugely too, until it is COWed. + * But if caller specified an address hint, respect that as before. + */ + if (uaddr) + return addr; + + if (shmem_huge != SHMEM_HUGE_FORCE) { + struct super_block *sb; + + if (file) { + VM_BUG_ON(file->f_op != &shmem_file_operations); + sb = file_inode(file)->i_sb; + } else { + /* + * Called directly from mm/mmap.c, or drivers/char/mem.c + * for "/dev/zero", to create a shared anonymous object. + */ + if (IS_ERR(shm_mnt)) + return addr; + sb = shm_mnt->mnt_sb; + } + if (SHMEM_SB(sb)->huge != SHMEM_HUGE_NEVER) + return addr; + } + + offset = (pgoff << PAGE_SHIFT) & (HPAGE_PMD_SIZE-1); + if (offset && offset + len < 2 * HPAGE_PMD_SIZE) + return addr; + if ((addr & (HPAGE_PMD_SIZE-1)) == offset) + return addr; + + inflated_len = len + HPAGE_PMD_SIZE - PAGE_SIZE; + if (inflated_len > TASK_SIZE) + return addr; + if (inflated_len < len) + return addr; + + inflated_addr = get_area(NULL, 0, inflated_len, 0, flags); + if (IS_ERR_VALUE(inflated_addr)) + return addr; + if (inflated_addr & ~PAGE_MASK) + return addr; + + inflated_offset = inflated_addr & (HPAGE_PMD_SIZE-1); + inflated_addr += offset - inflated_offset; + if (inflated_offset > offset) + inflated_addr += HPAGE_PMD_SIZE; + + if (inflated_addr > TASK_SIZE - len) + return addr; + return inflated_addr; +} + #ifdef CONFIG_NUMA static int shmem_set_policy(struct vm_area_struct *vma, struct mempolicy *mpol) { @@ -1456,7 +2035,7 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user) struct shmem_inode_info *info = SHMEM_I(inode); int retval = -ENOMEM; - spin_lock(&info->lock); + spin_lock_irq(&info->lock); if (lock && !(info->flags & VM_LOCKED)) { if (!user_shm_lock(inode->i_size, user)) goto out_nomem; @@ -1471,7 +2050,7 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user) retval = 0; out_nomem: - spin_unlock(&info->lock); + spin_unlock_irq(&info->lock); return retval; } @@ -1479,6 +2058,11 @@ static int shmem_mmap(struct file *file, struct vm_area_struct *vma) { file_accessed(file); vma->vm_ops = &shmem_vm_ops; + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE) && + ((vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK) < + (vma->vm_end & HPAGE_PMD_MASK)) { + khugepaged_enter(vma, vma->vm_flags); + } return 0; } @@ -1504,6 +2088,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode spin_lock_init(&info->lock); info->seals = F_SEAL_SEAL; info->flags = flags & VM_NORESERVE; + INIT_LIST_HEAD(&info->shrinklist); INIT_LIST_HEAD(&info->swaplist); simple_xattrs_init(&info->xattrs); cache_no_acl(inode); @@ -1589,12 +2174,23 @@ shmem_write_end(struct file *file, struct address_space *mapping, i_size_write(inode, pos + copied); if (!PageUptodate(page)) { + struct page *head = compound_head(page); + if (PageTransCompound(page)) { + int i; + + for (i = 0; i < HPAGE_PMD_NR; i++) { + if (head + i == page) + continue; + clear_highpage(head + i); + flush_dcache_page(head + i); + } + } if (copied < PAGE_SIZE) { unsigned from = pos & (PAGE_SIZE - 1); zero_user_segments(page, 0, from, from + copied, PAGE_SIZE); } - SetPageUptodate(page); + SetPageUptodate(head); } set_page_dirty(page); unlock_page(page); @@ -2225,9 +2821,11 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset, error = shmem_getpage(inode, index, &page, SGP_FALLOC); if (error) { /* Remove the !PageUptodate pages we added */ - shmem_undo_range(inode, - (loff_t)start << PAGE_SHIFT, - ((loff_t)index << PAGE_SHIFT) - 1, true); + if (index > start) { + shmem_undo_range(inode, + (loff_t)start << PAGE_SHIFT, + ((loff_t)index << PAGE_SHIFT) - 1, true); + } goto undone; } @@ -2858,11 +3456,24 @@ static int shmem_parse_options(char *options, struct shmem_sb_info *sbinfo, sbinfo->gid = make_kgid(current_user_ns(), gid); if (!gid_valid(sbinfo->gid)) goto bad_val; +#ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE + } else if (!strcmp(this_char, "huge")) { + int huge; + huge = shmem_parse_huge(value); + if (huge < 0) + goto bad_val; + if (!has_transparent_hugepage() && + huge != SHMEM_HUGE_NEVER) + goto bad_val; + sbinfo->huge = huge; +#endif +#ifdef CONFIG_NUMA } else if (!strcmp(this_char,"mpol")) { mpol_put(mpol); mpol = NULL; if (mpol_parse_str(value, &mpol)) goto bad_val; +#endif } else { pr_err("tmpfs: Bad mount option %s\n", this_char); goto error; @@ -2908,6 +3519,7 @@ static int shmem_remount_fs(struct super_block *sb, int *flags, char *data) goto out; error = 0; + sbinfo->huge = config.huge; sbinfo->max_blocks = config.max_blocks; sbinfo->max_inodes = config.max_inodes; sbinfo->free_inodes = config.max_inodes - inodes; @@ -2941,6 +3553,11 @@ static int shmem_show_options(struct seq_file *seq, struct dentry *root) if (!gid_eq(sbinfo->gid, GLOBAL_ROOT_GID)) seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, sbinfo->gid)); +#ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE + /* Rightly or wrongly, show huge mount option unmasked by shmem_huge */ + if (sbinfo->huge) + seq_printf(seq, ",huge=%s", shmem_format_huge(sbinfo->huge)); +#endif shmem_show_mpol(seq, sbinfo->mpol); return 0; } @@ -3070,6 +3687,8 @@ int shmem_fill_super(struct super_block *sb, void *data, int silent) if (percpu_counter_init(&sbinfo->used_blocks, 0, GFP_KERNEL)) goto failed; sbinfo->free_inodes = sbinfo->max_inodes; + spin_lock_init(&sbinfo->shrinklist_lock); + INIT_LIST_HEAD(&sbinfo->shrinklist); sb->s_maxbytes = MAX_LFS_FILESIZE; sb->s_blocksize = PAGE_SIZE; @@ -3159,6 +3778,7 @@ static const struct address_space_operations shmem_aops = { static const struct file_operations shmem_file_operations = { .mmap = shmem_mmap, + .get_unmapped_area = shmem_get_unmapped_area, #ifdef CONFIG_TMPFS .llseek = shmem_file_llseek, .read_iter = shmem_file_read_iter, @@ -3231,6 +3851,10 @@ static const struct super_operations shmem_ops = { .evict_inode = shmem_evict_inode, .drop_inode = generic_delete_inode, .put_super = shmem_put_super, +#ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE + .nr_cached_objects = shmem_unused_huge_count, + .free_cached_objects = shmem_unused_huge_scan, +#endif }; static const struct vm_operations_struct shmem_vm_ops = { @@ -3280,6 +3904,13 @@ int __init shmem_init(void) pr_err("Could not kern_mount tmpfs\n"); goto out1; } + +#ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE + if (has_transparent_hugepage() && shmem_huge < SHMEM_HUGE_DENY) + SHMEM_SB(shm_mnt->mnt_sb)->huge = shmem_huge; + else + shmem_huge = 0; /* just in case it was patched */ +#endif return 0; out1: @@ -3291,6 +3922,91 @@ out3: return error; } +#if defined(CONFIG_TRANSPARENT_HUGE_PAGECACHE) && defined(CONFIG_SYSFS) +static ssize_t shmem_enabled_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + int values[] = { + SHMEM_HUGE_ALWAYS, + SHMEM_HUGE_WITHIN_SIZE, + SHMEM_HUGE_ADVISE, + SHMEM_HUGE_NEVER, + SHMEM_HUGE_DENY, + SHMEM_HUGE_FORCE, + }; + int i, count; + + for (i = 0, count = 0; i < ARRAY_SIZE(values); i++) { + const char *fmt = shmem_huge == values[i] ? "[%s] " : "%s "; + + count += sprintf(buf + count, fmt, + shmem_format_huge(values[i])); + } + buf[count - 1] = '\n'; + return count; +} + +static ssize_t shmem_enabled_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + char tmp[16]; + int huge; + + if (count + 1 > sizeof(tmp)) + return -EINVAL; + memcpy(tmp, buf, count); + tmp[count] = '\0'; + if (count && tmp[count - 1] == '\n') + tmp[count - 1] = '\0'; + + huge = shmem_parse_huge(tmp); + if (huge == -EINVAL) + return -EINVAL; + if (!has_transparent_hugepage() && + huge != SHMEM_HUGE_NEVER && huge != SHMEM_HUGE_DENY) + return -EINVAL; + + shmem_huge = huge; + if (shmem_huge < SHMEM_HUGE_DENY) + SHMEM_SB(shm_mnt->mnt_sb)->huge = shmem_huge; + return count; +} + +struct kobj_attribute shmem_enabled_attr = + __ATTR(shmem_enabled, 0644, shmem_enabled_show, shmem_enabled_store); + +bool shmem_huge_enabled(struct vm_area_struct *vma) +{ + struct inode *inode = file_inode(vma->vm_file); + struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb); + loff_t i_size; + pgoff_t off; + + if (shmem_huge == SHMEM_HUGE_FORCE) + return true; + if (shmem_huge == SHMEM_HUGE_DENY) + return false; + switch (sbinfo->huge) { + case SHMEM_HUGE_NEVER: + return false; + case SHMEM_HUGE_ALWAYS: + return true; + case SHMEM_HUGE_WITHIN_SIZE: + off = round_up(vma->vm_pgoff, HPAGE_PMD_NR); + i_size = round_up(i_size_read(inode), PAGE_SIZE); + if (i_size >= HPAGE_PMD_SIZE && + i_size >> PAGE_SHIFT >= off) + return true; + case SHMEM_HUGE_ADVISE: + /* TODO: implement fadvise() hints */ + return (vma->vm_flags & VM_HUGEPAGE); + default: + VM_BUG_ON(1); + return false; + } +} +#endif /* CONFIG_TRANSPARENT_HUGE_PAGECACHE && CONFIG_SYSFS */ + #else /* !CONFIG_SHMEM */ /* @@ -3333,6 +4049,15 @@ void shmem_unlock_mapping(struct address_space *mapping) { } +#ifdef CONFIG_MMU +unsigned long shmem_get_unmapped_area(struct file *file, + unsigned long addr, unsigned long len, + unsigned long pgoff, unsigned long flags) +{ + return current->mm->get_unmapped_area(file, addr, len, pgoff, flags); +} +#endif + void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend) { truncate_inode_pages_range(inode->i_mapping, lstart, lend); @@ -3459,6 +4184,13 @@ int shmem_zero_setup(struct vm_area_struct *vma) fput(vma->vm_file); vma->vm_file = file; vma->vm_ops = &shmem_vm_ops; + + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGE_PAGECACHE) && + ((vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK) < + (vma->vm_end & HPAGE_PMD_MASK)) { + khugepaged_enter(vma, vma->vm_flags); + } + return 0; } |