diff options
Diffstat (limited to 'mm/hugetlb.c')
| -rw-r--r-- | mm/hugetlb.c | 1400 |
1 files changed, 992 insertions, 408 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index bb0b7c128015..0b7656e804d1 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1,6 +1,6 @@ /* * Generic hugetlb support. - * (C) William Irwin, April 2004 + * (C) Nadia Yvette Chambers, April 2004 */ #include <linux/list.h> #include <linux/init.h> @@ -21,20 +21,22 @@ #include <linux/rmap.h> #include <linux/swap.h> #include <linux/swapops.h> +#include <linux/page-isolation.h> #include <asm/page.h> #include <asm/pgtable.h> -#include <asm/io.h> +#include <asm/tlb.h> +#include <linux/io.h> #include <linux/hugetlb.h> +#include <linux/hugetlb_cgroup.h> #include <linux/node.h> #include "internal.h" const unsigned long hugetlb_zero = 0, hugetlb_infinity = ~0UL; -static gfp_t htlb_alloc_mask = GFP_HIGHUSER; unsigned long hugepages_treat_as_movable; -static int max_hstate; +int hugetlb_max_hstate __read_mostly; unsigned int default_hstate_idx; struct hstate hstates[HUGE_MAX_HSTATE]; @@ -45,27 +47,103 @@ static struct hstate * __initdata parsed_hstate; static unsigned long __initdata default_hstate_max_huge_pages; static unsigned long __initdata default_hstate_size; -#define for_each_hstate(h) \ - for ((h) = hstates; (h) < &hstates[max_hstate]; (h)++) - /* - * Protects updates to hugepage_freelists, nr_huge_pages, and free_huge_pages + * Protects updates to hugepage_freelists, hugepage_activelist, nr_huge_pages, + * free_huge_pages, and surplus_huge_pages. */ -static DEFINE_SPINLOCK(hugetlb_lock); +DEFINE_SPINLOCK(hugetlb_lock); + +static inline void unlock_or_release_subpool(struct hugepage_subpool *spool) +{ + bool free = (spool->count == 0) && (spool->used_hpages == 0); + + spin_unlock(&spool->lock); + + /* If no pages are used, and no other handles to the subpool + * remain, free the subpool the subpool remain */ + if (free) + kfree(spool); +} + +struct hugepage_subpool *hugepage_new_subpool(long nr_blocks) +{ + struct hugepage_subpool *spool; + + spool = kmalloc(sizeof(*spool), GFP_KERNEL); + if (!spool) + return NULL; + + spin_lock_init(&spool->lock); + spool->count = 1; + spool->max_hpages = nr_blocks; + spool->used_hpages = 0; + + return spool; +} + +void hugepage_put_subpool(struct hugepage_subpool *spool) +{ + spin_lock(&spool->lock); + BUG_ON(!spool->count); + spool->count--; + unlock_or_release_subpool(spool); +} + +static int hugepage_subpool_get_pages(struct hugepage_subpool *spool, + long delta) +{ + int ret = 0; + + if (!spool) + return 0; + + spin_lock(&spool->lock); + if ((spool->used_hpages + delta) <= spool->max_hpages) { + spool->used_hpages += delta; + } else { + ret = -ENOMEM; + } + spin_unlock(&spool->lock); + + return ret; +} + +static void hugepage_subpool_put_pages(struct hugepage_subpool *spool, + long delta) +{ + if (!spool) + return; + + spin_lock(&spool->lock); + spool->used_hpages -= delta; + /* If hugetlbfs_put_super couldn't free spool due to + * an outstanding quota reference, free it now. */ + unlock_or_release_subpool(spool); +} + +static inline struct hugepage_subpool *subpool_inode(struct inode *inode) +{ + return HUGETLBFS_SB(inode->i_sb)->spool; +} + +static inline struct hugepage_subpool *subpool_vma(struct vm_area_struct *vma) +{ + return subpool_inode(file_inode(vma->vm_file)); +} /* * Region tracking -- allows tracking of reservations and instantiated pages * across the pages in a mapping. * * The region data structures are protected by a combination of the mmap_sem - * and the hugetlb_instantion_mutex. To access or modify a region the caller + * and the hugetlb_instantiation_mutex. To access or modify a region the caller * must either hold the mmap_sem for write, or the mmap_sem for read and - * the hugetlb_instantiation mutex: + * the hugetlb_instantiation_mutex: * - * down_write(&mm->mmap_sem); + * down_write(&mm->mmap_sem); * or - * down_read(&mm->mmap_sem); - * mutex_lock(&hugetlb_instantiation_mutex); + * down_read(&mm->mmap_sem); + * mutex_lock(&hugetlb_instantiation_mutex); */ struct file_region { struct list_head link; @@ -146,7 +224,7 @@ static long region_chg(struct list_head *head, long f, long t) if (rg->from > t) return chg; - /* We overlap with this area, if it extends futher than + /* We overlap with this area, if it extends further than * us then we must extend ourselves. Account for its * existing reservation. */ if (rg->to > t) { @@ -195,8 +273,8 @@ static long region_count(struct list_head *head, long f, long t) /* Locate each segment we overlap with, and count that overlap. */ list_for_each_entry(rg, head, link) { - int seg_from; - int seg_to; + long seg_from; + long seg_to; if (rg->to <= f) continue; @@ -242,7 +320,7 @@ unsigned long vma_kernel_pagesize(struct vm_area_struct *vma) hstate = hstate_vma(vma); - return 1UL << (hstate->order + PAGE_SHIFT); + return 1UL << huge_page_shift(hstate); } EXPORT_SYMBOL_GPL(vma_kernel_pagesize); @@ -357,25 +435,6 @@ static int is_vma_resv_set(struct vm_area_struct *vma, unsigned long flag) return (get_vma_private_data(vma) & flag) != 0; } -/* Decrement the reserved pages in the hugepage pool by one */ -static void decrement_hugepage_resv_vma(struct hstate *h, - struct vm_area_struct *vma) -{ - if (vma->vm_flags & VM_NORESERVE) - return; - - if (vma->vm_flags & VM_MAYSHARE) { - /* Shared mappings always use reserves */ - h->resv_huge_pages--; - } else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { - /* - * Only the process that called mmap() has reserves for - * private mappings. - */ - h->resv_huge_pages--; - } -} - /* Reset counters to 0 and clear all HPAGE_RESV_* flags */ void reset_vma_resv_huge_pages(struct vm_area_struct *vma) { @@ -385,12 +444,35 @@ void reset_vma_resv_huge_pages(struct vm_area_struct *vma) } /* Returns true if the VMA has associated reserve pages */ -static int vma_has_reserves(struct vm_area_struct *vma) +static int vma_has_reserves(struct vm_area_struct *vma, long chg) { + if (vma->vm_flags & VM_NORESERVE) { + /* + * This address is already reserved by other process(chg == 0), + * so, we should decrement reserved count. Without decrementing, + * reserve count remains after releasing inode, because this + * allocated page will go into page cache and is regarded as + * coming from reserved pool in releasing step. Currently, we + * don't have any other solution to deal with this situation + * properly, so add work-around here. + */ + if (vma->vm_flags & VM_MAYSHARE && chg == 0) + return 1; + else + return 0; + } + + /* Shared mappings always use reserves */ if (vma->vm_flags & VM_MAYSHARE) return 1; + + /* + * Only the process that called mmap() has reserves for + * private mappings. + */ if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) return 1; + return 0; } @@ -431,7 +513,7 @@ void copy_huge_page(struct page *dst, struct page *src) static void enqueue_huge_page(struct hstate *h, struct page *page) { int nid = page_to_nid(page); - list_add(&page->lru, &h->hugepage_freelists[nid]); + list_move(&page->lru, &h->hugepage_freelists[nid]); h->free_huge_pages++; h->free_huge_pages_node[nid]++; } @@ -440,19 +522,35 @@ static struct page *dequeue_huge_page_node(struct hstate *h, int nid) { struct page *page; - if (list_empty(&h->hugepage_freelists[nid])) + list_for_each_entry(page, &h->hugepage_freelists[nid], lru) + if (!is_migrate_isolate_page(page)) + break; + /* + * if 'non-isolated free hugepage' not found on the list, + * the allocation fails. + */ + if (&h->hugepage_freelists[nid] == &page->lru) return NULL; - page = list_entry(h->hugepage_freelists[nid].next, struct page, lru); - list_del(&page->lru); + list_move(&page->lru, &h->hugepage_activelist); set_page_refcounted(page); h->free_huge_pages--; h->free_huge_pages_node[nid]--; return page; } +/* Movability of hugepages depends on migration support. */ +static inline gfp_t htlb_alloc_mask(struct hstate *h) +{ + if (hugepages_treat_as_movable || hugepage_migration_support(h)) + return GFP_HIGHUSER_MOVABLE; + else + return GFP_HIGHUSER; +} + static struct page *dequeue_huge_page_vma(struct hstate *h, struct vm_area_struct *vma, - unsigned long address, int avoid_reserve) + unsigned long address, int avoid_reserve, + long chg) { struct page *page = NULL; struct mempolicy *mpol; @@ -460,38 +558,50 @@ static struct page *dequeue_huge_page_vma(struct hstate *h, struct zonelist *zonelist; struct zone *zone; struct zoneref *z; + unsigned int cpuset_mems_cookie; - get_mems_allowed(); - zonelist = huge_zonelist(vma, address, - htlb_alloc_mask, &mpol, &nodemask); /* * A child process with MAP_PRIVATE mappings created by their parent * have no page reserves. This check ensures that reservations are * not "stolen". The child may still get SIGKILLed */ - if (!vma_has_reserves(vma) && + if (!vma_has_reserves(vma, chg) && h->free_huge_pages - h->resv_huge_pages == 0) goto err; /* If reserves cannot be used, ensure enough pages are in the pool */ if (avoid_reserve && h->free_huge_pages - h->resv_huge_pages == 0) - goto err;; + goto err; + +retry_cpuset: + cpuset_mems_cookie = get_mems_allowed(); + zonelist = huge_zonelist(vma, address, + htlb_alloc_mask(h), &mpol, &nodemask); for_each_zone_zonelist_nodemask(zone, z, zonelist, MAX_NR_ZONES - 1, nodemask) { - if (cpuset_zone_allowed_softwall(zone, htlb_alloc_mask)) { + if (cpuset_zone_allowed_softwall(zone, htlb_alloc_mask(h))) { page = dequeue_huge_page_node(h, zone_to_nid(zone)); if (page) { - if (!avoid_reserve) - decrement_hugepage_resv_vma(h, vma); + if (avoid_reserve) + break; + if (!vma_has_reserves(vma, chg)) + break; + + SetPagePrivate(page); + h->resv_huge_pages--; break; } } } -err: + mpol_cond_put(mpol); - put_mems_allowed(); + if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !page)) + goto retry_cpuset; return page; + +err: + return NULL; } static void update_and_free_page(struct hstate *h, struct page *page) @@ -503,10 +613,12 @@ static void update_and_free_page(struct hstate *h, struct page *page) h->nr_huge_pages--; h->nr_huge_pages_node[page_to_nid(page)]--; for (i = 0; i < pages_per_huge_page(h); i++) { - page[i].flags &= ~(1 << PG_locked | 1 << PG_error | 1 << PG_referenced | - 1 << PG_dirty | 1 << PG_active | 1 << PG_reserved | - 1 << PG_private | 1<< PG_writeback); + page[i].flags &= ~(1 << PG_locked | 1 << PG_error | + 1 << PG_referenced | 1 << PG_dirty | + 1 << PG_active | 1 << PG_reserved | + 1 << PG_private | 1 << PG_writeback); } + VM_BUG_ON(hugetlb_cgroup_from_page(page)); set_compound_page_dtor(page, NULL); set_page_refcounted(page); arch_release_hugepage(page); @@ -532,32 +644,43 @@ static void free_huge_page(struct page *page) */ struct hstate *h = page_hstate(page); int nid = page_to_nid(page); - struct address_space *mapping; + struct hugepage_subpool *spool = + (struct hugepage_subpool *)page_private(page); + bool restore_reserve; - mapping = (struct address_space *) page_private(page); set_page_private(page, 0); page->mapping = NULL; BUG_ON(page_count(page)); BUG_ON(page_mapcount(page)); - INIT_LIST_HEAD(&page->lru); + restore_reserve = PagePrivate(page); + ClearPagePrivate(page); spin_lock(&hugetlb_lock); + hugetlb_cgroup_uncharge_page(hstate_index(h), + pages_per_huge_page(h), page); + if (restore_reserve) + h->resv_huge_pages++; + if (h->surplus_huge_pages_node[nid] && huge_page_order(h) < MAX_ORDER) { + /* remove the page from active list */ + list_del(&page->lru); update_and_free_page(h, page); h->surplus_huge_pages--; h->surplus_huge_pages_node[nid]--; } else { + arch_clear_hugepage_flags(page); enqueue_huge_page(h, page); } spin_unlock(&hugetlb_lock); - if (mapping) - hugetlb_put_quota(mapping, 1); + hugepage_subpool_put_pages(spool, 1); } static void prep_new_huge_page(struct hstate *h, struct page *page, int nid) { + INIT_LIST_HEAD(&page->lru); set_compound_page_dtor(page, free_huge_page); spin_lock(&hugetlb_lock); + set_hugetlb_cgroup(page, NULL); h->nr_huge_pages++; h->nr_huge_pages_node[nid]++; spin_unlock(&hugetlb_lock); @@ -573,12 +696,32 @@ static void prep_compound_gigantic_page(struct page *page, unsigned long order) /* we rely on prep_new_huge_page to set the destructor */ set_compound_order(page, order); __SetPageHead(page); + __ClearPageReserved(page); for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) { __SetPageTail(p); + /* + * For gigantic hugepages allocated through bootmem at + * boot, it's safer to be consistent with the not-gigantic + * hugepages and clear the PG_reserved bit from all tail pages + * too. Otherwse drivers using get_user_pages() to access tail + * pages may get the reference counting wrong if they see + * PG_reserved set on a tail page (despite the head page not + * having PG_reserved set). Enforcing this consistency between + * head and tail pages allows drivers to optimize away a check + * on the head page when they need know if put_page() is needed + * after get_user_pages(). + */ + __ClearPageReserved(p); + set_page_count(p, 0); p->first_page = page; } } +/* + * PageHuge() only returns true for hugetlbfs pages, but not for normal or + * transparent huge pages. See the PageTransHuge() documentation for more + * details. + */ int PageHuge(struct page *page) { compound_page_dtor *dtor; @@ -591,9 +734,25 @@ int PageHuge(struct page *page) return dtor == free_huge_page; } - EXPORT_SYMBOL_GPL(PageHuge); +pgoff_t __basepage_index(struct page *page) +{ + struct page *page_head = compound_head(page); + pgoff_t index = page_index(page_head); + unsigned long compound_idx; + + if (!PageHuge(page_head)) + return page_index(page); + + if (compound_order(page_head) >= MAX_ORDER) + compound_idx = page_to_pfn(page) - page_to_pfn(page_head); + else + compound_idx = page - page_head; + + return (index << compound_order(page_head)) + compound_idx; +} + static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) { struct page *page; @@ -602,7 +761,7 @@ static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid) return NULL; page = alloc_pages_exact_node(nid, - htlb_alloc_mask|__GFP_COMP|__GFP_THISNODE| + htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE| __GFP_REPEAT|__GFP_NOWARN, huge_page_order(h)); if (page) { @@ -659,33 +818,6 @@ static int hstate_next_node_to_alloc(struct hstate *h, return nid; } -static int alloc_fresh_huge_page(struct hstate *h, nodemask_t *nodes_allowed) -{ - struct page *page; - int start_nid; - int next_nid; - int ret = 0; - - start_nid = hstate_next_node_to_alloc(h, nodes_allowed); - next_nid = start_nid; - - do { - page = alloc_fresh_huge_page_node(h, next_nid); - if (page) { - ret = 1; - break; - } - next_nid = hstate_next_node_to_alloc(h, nodes_allowed); - } while (next_nid != start_nid); - - if (ret) - count_vm_event(HTLB_BUDDY_PGALLOC); - else - count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); - - return ret; -} - /* * helper for free_pool_huge_page() - return the previously saved * node ["this node"] from which to free a huge page. Advance the @@ -704,6 +836,40 @@ static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed) return nid; } +#define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask) \ + for (nr_nodes = nodes_weight(*mask); \ + nr_nodes > 0 && \ + ((node = hstate_next_node_to_alloc(hs, mask)) || 1); \ + nr_nodes--) + +#define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \ + for (nr_nodes = nodes_weight(*mask); \ + nr_nodes > 0 && \ + ((node = hstate_next_node_to_free(hs, mask)) || 1); \ + nr_nodes--) + +static int alloc_fresh_huge_page(struct hstate *h, nodemask_t *nodes_allowed) +{ + struct page *page; + int nr_nodes, node; + int ret = 0; + + for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { + page = alloc_fresh_huge_page_node(h, node); + if (page) { + ret = 1; + break; + } + } + + if (ret) + count_vm_event(HTLB_BUDDY_PGALLOC); + else + count_vm_event(HTLB_BUDDY_PGALLOC_FAIL); + + return ret; +} + /* * Free huge page from pool from next node to free. * Attempt to keep persistent huge pages more or less @@ -713,40 +879,73 @@ static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed) static int free_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed, bool acct_surplus) { - int start_nid; - int next_nid; + int nr_nodes, node; int ret = 0; - start_nid = hstate_next_node_to_free(h, nodes_allowed); - next_nid = start_nid; - - do { + for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { /* * If we're returning unused surplus pages, only examine * nodes with surplus pages. */ - if ((!acct_surplus || h->surplus_huge_pages_node[next_nid]) && - !list_empty(&h->hugepage_freelists[next_nid])) { + if ((!acct_surplus || h->surplus_huge_pages_node[node]) && + !list_empty(&h->hugepage_freelists[node])) { struct page *page = - list_entry(h->hugepage_freelists[next_nid].next, + list_entry(h->hugepage_freelists[node].next, struct page, lru); list_del(&page->lru); h->free_huge_pages--; - h->free_huge_pages_node[next_nid]--; + h->free_huge_pages_node[node]--; if (acct_surplus) { h->surplus_huge_pages--; - h->surplus_huge_pages_node[next_nid]--; + h->surplus_huge_pages_node[node]--; } update_and_free_page(h, page); ret = 1; break; } - next_nid = hstate_next_node_to_free(h, nodes_allowed); - } while (next_nid != start_nid); + } return ret; } +/* + * Dissolve a given free hugepage into free buddy pages. This function does + * nothing for in-use (including surplus) hugepages. + */ +static void dissolve_free_huge_page(struct page *page) +{ + spin_lock(&hugetlb_lock); + if (PageHuge(page) && !page_count(page)) { + struct hstate *h = page_hstate(page); + int nid = page_to_nid(page); + list_del(&page->lru); + h->free_huge_pages--; + h->free_huge_pages_node[nid]--; + update_and_free_page(h, page); + } + spin_unlock(&hugetlb_lock); +} + +/* + * Dissolve free hugepages in a given pfn range. Used by memory hotplug to + * make specified memory blocks removable from the system. + * Note that start_pfn should aligned with (minimum) hugepage size. + */ +void dissolve_free_huge_pages(unsigned long start_pfn, unsigned long end_pfn) +{ + unsigned int order = 8 * sizeof(void *); + unsigned long pfn; + struct hstate *h; + + /* Set scan step to minimum hugepage size */ + for_each_hstate(h) + if (order > huge_page_order(h)) + order = huge_page_order(h); + VM_BUG_ON(!IS_ALIGNED(start_pfn, 1 << order)); + for (pfn = start_pfn; pfn < end_pfn; pfn += 1 << order) + dissolve_free_huge_page(pfn_to_page(pfn)); +} + static struct page *alloc_buddy_huge_page(struct hstate *h, int nid) { struct page *page; @@ -789,23 +988,25 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid) spin_unlock(&hugetlb_lock); if (nid == NUMA_NO_NODE) - page = alloc_pages(htlb_alloc_mask|__GFP_COMP| + page = alloc_pages(htlb_alloc_mask(h)|__GFP_COMP| __GFP_REPEAT|__GFP_NOWARN, huge_page_order(h)); else page = alloc_pages_exact_node(nid, - htlb_alloc_mask|__GFP_COMP|__GFP_THISNODE| + htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE| __GFP_REPEAT|__GFP_NOWARN, huge_page_order(h)); if (page && arch_prepare_hugepage(page)) { __free_pages(page, huge_page_order(h)); - return NULL; + page = NULL; } spin_lock(&hugetlb_lock); if (page) { + INIT_LIST_HEAD(&page->lru); r_nid = page_to_nid(page); set_compound_page_dtor(page, free_huge_page); + set_hugetlb_cgroup(page, NULL); /* * We incremented the global counters already */ @@ -829,10 +1030,11 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid) */ struct page *alloc_huge_page_node(struct hstate *h, int nid) { - struct page *page; + struct page *page = NULL; spin_lock(&hugetlb_lock); - page = dequeue_huge_page_node(h, nid); + if (h->free_huge_pages - h->resv_huge_pages > 0) + page = dequeue_huge_page_node(h, nid); spin_unlock(&hugetlb_lock); if (!page) @@ -842,7 +1044,7 @@ struct page *alloc_huge_page_node(struct hstate *h, int nid) } /* - * Increase the hugetlb pool such that it can accomodate a reservation + * Increase the hugetlb pool such that it can accommodate a reservation * of size 'delta'. */ static int gather_surplus_pages(struct hstate *h, int delta) @@ -851,6 +1053,7 @@ static int gather_surplus_pages(struct hstate *h, int delta) struct page *page, *tmp; int ret, i; int needed, allocated; + bool alloc_ok = true; needed = (h->resv_huge_pages + delta) - h->free_huge_pages; if (needed <= 0) { @@ -866,17 +1069,13 @@ retry: spin_unlock(&hugetlb_lock); for (i = 0; i < needed; i++) { page = alloc_buddy_huge_page(h, NUMA_NO_NODE); - if (!page) - /* - * We were not able to allocate enough pages to - * satisfy the entire reservation so we free what - * we've allocated so far. - */ - goto free; - + if (!page) { + alloc_ok = false; + break; + } list_add(&page->lru, &surplus_list); } - allocated += needed; + allocated += i; /* * After retaking hugetlb_lock, we need to recalculate 'needed' @@ -885,12 +1084,19 @@ retry: spin_lock(&hugetlb_lock); needed = (h->resv_huge_pages + delta) - (h->free_huge_pages + allocated); - if (needed > 0) - goto retry; - + if (needed > 0) { + if (alloc_ok) + goto retry; + /* + * We were not able to allocate enough pages to + * satisfy the entire reservation so we free what + * we've allocated so far. + */ + goto free; + } /* * The surplus_list now contains _at_least_ the number of extra pages - * needed to accomodate the reservation. Add the appropriate number + * needed to accommodate the reservation. Add the appropriate number * of pages to the hugetlb pool and free the extras back to the buddy * allocator. Commit the entire reservation here to prevent another * process from stealing the pages as they are added to the pool but @@ -900,12 +1106,10 @@ retry: h->resv_huge_pages += delta; ret = 0; - spin_unlock(&hugetlb_lock); /* Free the needed pages to the hugetlb pool */ list_for_each_entry_safe(page, tmp, &surplus_list, lru) { if ((--needed) < 0) break; - list_del(&page->lru); /* * This page is now managed by the hugetlb allocator and has * no users -- drop the buddy allocator's reference. @@ -914,15 +1118,12 @@ retry: VM_BUG_ON(page_count(page)); enqueue_huge_page(h, page); } +free: + spin_unlock(&hugetlb_lock); /* Free unnecessary surplus pages to the buddy allocator */ -free: - if (!list_empty(&surplus_list)) { - list_for_each_entry_safe(page, tmp, &surplus_list, lru) { - list_del(&page->lru); - put_page(page); - } - } + list_for_each_entry_safe(page, tmp, &surplus_list, lru) + put_page(page); spin_lock(&hugetlb_lock); return ret; @@ -957,7 +1158,7 @@ static void return_unused_surplus_pages(struct hstate *h, * on-line nodes with memory and will handle the hstate accounting. */ while (nr_pages--) { - if (!free_pool_huge_page(h, &node_states[N_HIGH_MEMORY], 1)) + if (!free_pool_huge_page(h, &node_states[N_MEMORY], 1)) break; } } @@ -965,11 +1166,12 @@ static void return_unused_surplus_pages(struct hstate *h, /* * Determine if the huge page at addr within the vma has an associated * reservation. Where it does not we will need to logically increase - * reservation and actually increase quota before an allocation can occur. - * Where any new reservation would be required the reservation change is - * prepared, but not committed. Once the page has been quota'd allocated - * an instantiated the change should be committed via vma_commit_reservation. - * No action is required on failure. + * reservation and actually increase subpool usage before an allocation + * can occur. Where any new reservation would be required the + * reservation change is prepared, but not committed. Once the page + * has been allocated from the subpool and instantiated the change should + * be committed via vma_commit_reservation. No action is required on + * failure. */ static long vma_needs_reservation(struct hstate *h, struct vm_area_struct *vma, unsigned long addr) @@ -988,9 +1190,9 @@ static long vma_needs_reservation(struct hstate *h, } else { long err; pgoff_t idx = vma_hugecache_offset(h, vma, addr); - struct resv_map *reservations = vma_resv_map(vma); + struct resv_map *resv = vma_resv_map(vma); - err = region_chg(&reservations->regions, idx, idx + 1); + err = region_chg(&resv->regions, idx, idx + 1); if (err < 0) return err; return 0; @@ -1008,66 +1210,94 @@ static void vma_commit_reservation(struct hstate *h, } else if (is_vma_resv_set(vma, HPAGE_RESV_OWNER)) { pgoff_t idx = vma_hugecache_offset(h, vma, addr); - struct resv_map *reservations = vma_resv_map(vma); + struct resv_map *resv = vma_resv_map(vma); /* Mark this page used in the map. */ - region_add(&reservations->regions, idx, idx + 1); + region_add(&resv->regions, idx, idx + 1); } } static struct page *alloc_huge_page(struct vm_area_struct *vma, unsigned long addr, int avoid_reserve) { + struct hugepage_subpool *spool = subpool_vma(vma); struct hstate *h = hstate_vma(vma); struct page *page; - struct address_space *mapping = vma->vm_file->f_mapping; - struct inode *inode = mapping->host; long chg; + int ret, idx; + struct hugetlb_cgroup *h_cg; + idx = hstate_index(h); /* - * Processes that did not create the mapping will have no reserves and - * will not have accounted against quota. Check that the quota can be - * made before satisfying the allocation - * MAP_NORESERVE mappings may also need pages and quota allocated - * if no reserve mapping overlaps. + * Processes that did not create the mapping will have no + * reserves and will not have accounted against subpool + * limit. Check that the subpool limit can be made before + * satisfying the allocation MAP_NORESERVE mappings may also + * need pages and subpool limit allocated allocated if no reserve + * mapping overlaps. */ chg = vma_needs_reservation(h, vma, addr); if (chg < 0) - return ERR_PTR(chg); - if (chg) - if (hugetlb_get_quota(inode->i_mapping, chg)) + return ERR_PTR(-ENOMEM); + if (chg || avoid_reserve) + if (hugepage_subpool_get_pages(spool, 1)) return ERR_PTR(-ENOSPC); + ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg); + if (ret) { + if (chg || avoid_reserve) + hugepage_subpool_put_pages(spool, 1); + return ERR_PTR(-ENOSPC); + } spin_lock(&hugetlb_lock); - page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve); - spin_unlock(&hugetlb_lock); - + page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, chg); if (!page) { + spin_unlock(&hugetlb_lock); page = alloc_buddy_huge_page(h, NUMA_NO_NODE); if (!page) { - hugetlb_put_quota(inode->i_mapping, chg); - return ERR_PTR(-VM_FAULT_SIGBUS); + hugetlb_cgroup_uncharge_cgroup(idx, + pages_per_huge_page(h), + h_cg); + if (chg || avoid_reserve) + hugepage_subpool_put_pages(spool, 1); + return ERR_PTR(-ENOSPC); } + spin_lock(&hugetlb_lock); + list_move(&page->lru, &h->hugepage_activelist); + /* Fall through */ } + hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, page); + spin_unlock(&hugetlb_lock); - set_page_private(page, (unsigned long) mapping); + set_page_private(page, (unsigned long)spool); vma_commit_reservation(h, vma, addr); + return page; +} +/* + * alloc_huge_page()'s wrapper which simply returns the page if allocation + * succeeds, otherwise NULL. This function is called from new_vma_page(), + * where no ERR_VALUE is expected to be returned. + */ +struct page *alloc_huge_page_noerr(struct vm_area_struct *vma, + unsigned long addr, int avoid_reserve) +{ + struct page *page = alloc_huge_page(vma, addr, avoid_reserve); + if (IS_ERR(page)) + page = NULL; return page; } int __weak alloc_bootmem_huge_page(struct hstate *h) { struct huge_bootmem_page *m; - int nr_nodes = nodes_weight(node_states[N_HIGH_MEMORY]); + int nr_nodes, node; - while (nr_nodes) { + for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) { void *addr; - addr = __alloc_bootmem_node_nopanic( - NODE_DATA(hstate_next_node_to_alloc(h, - &node_states[N_HIGH_MEMORY])), + addr = __alloc_bootmem_node_nopanic(NODE_DATA(node), huge_page_size(h), huge_page_size(h), 0); if (addr) { @@ -1079,7 +1309,6 @@ int __weak alloc_bootmem_huge_page(struct hstate *h) m = addr; goto found; } - nr_nodes--; } return 0; @@ -1105,12 +1334,28 @@ static void __init gather_bootmem_prealloc(void) struct huge_bootmem_page *m; list_for_each_entry(m, &huge_boot_pages, list) { - struct page *page = virt_to_page(m); struct hstate *h = m->hstate; - __ClearPageReserved(page); + struct page *page; + +#ifdef CONFIG_HIGHMEM + page = pfn_to_page(m->phys >> PAGE_SHIFT); + free_bootmem_late((unsigned long)m, + sizeof(struct huge_bootmem_page)); +#else + page = virt_to_page(m); +#endif WARN_ON(page_count(page) != 1); prep_compound_huge_page(page, h->order); + WARN_ON(PageReserved(page)); prep_new_huge_page(h, page, page_to_nid(page)); + /* + * If we had gigantic hugepages allocated at boot time, we need + * to restore the 'stolen' pages to totalram_pages in order to + * fix confusing memory reports from free(1) and another + * side-effects, like CommitLimit going negative. + */ + if (h->order > (MAX_ORDER - 1)) + adjust_managed_page_count(page, 1 << h->order); } } @@ -1123,7 +1368,7 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h) if (!alloc_bootmem_huge_page(h)) break; } else if (!alloc_fresh_huge_page(h, - &node_states[N_HIGH_MEMORY])) + &node_states[N_MEMORY])) break; } h->max_huge_pages = i; @@ -1157,8 +1402,7 @@ static void __init report_hugepages(void) for_each_hstate(h) { char buf[32]; - printk(KERN_INFO "HugeTLB registered %s page size, " - "pre-allocated %ld pages\n", + pr_info("HugeTLB registered %s page size, pre-allocated %ld pages\n", memfmt(buf, huge_page_size(h)), h->free_huge_pages); } @@ -1203,48 +1447,28 @@ static inline void try_to_free_low(struct hstate *h, unsigned long count, static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed, int delta) { - int start_nid, next_nid; - int ret = 0; + int nr_nodes, node; VM_BUG_ON(delta != -1 && delta != 1); - if (delta < 0) - start_nid = hstate_next_node_to_alloc(h, nodes_allowed); - else - start_nid = hstate_next_node_to_free(h, nodes_allowed); - next_nid = start_nid; - - do { - int nid = next_nid; - if (delta < 0) { - /* - * To shrink on this node, there must be a surplus page - */ - if (!h->surplus_huge_pages_node[nid]) { - next_nid = hstate_next_node_to_alloc(h, - nodes_allowed); - continue; - } + if (delta < 0) { + for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) { + if (h->surplus_huge_pages_node[node]) + goto found; } - if (delta > 0) { - /* - * Surplus cannot exceed the total number of pages - */ - if (h->surplus_huge_pages_node[nid] >= - h->nr_huge_pages_node[nid]) { - next_nid = hstate_next_node_to_free(h, - nodes_allowed); - continue; - } + } else { + for_each_node_mask_to_free(h, nr_nodes, node, nodes_allowed) { + if (h->surplus_huge_pages_node[node] < + h->nr_huge_pages_node[node]) + goto found; } + } + return 0; - h->surplus_huge_pages += delta; - h->surplus_huge_pages_node[nid] += delta; - ret = 1; - break; - } while (next_nid != start_nid); - - return ret; +found: + h->surplus_huge_pages += delta; + h->surplus_huge_pages_node[node] += delta; + return 1; } #define persistent_huge_pages(h) (h->nr_huge_pages - h->surplus_huge_pages) @@ -1374,7 +1598,7 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy, struct hstate *h; NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY); - err = strict_strtoul(buf, 10, &count); + err = kstrtoul(buf, 10, &count); if (err) goto out; @@ -1391,7 +1615,7 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy, if (!(obey_mempolicy && init_nodemask_of_mempolicy(nodes_allowed))) { NODEMASK_FREE(nodes_allowed); - nodes_allowed = &node_states[N_HIGH_MEMORY]; + nodes_allowed = &node_states[N_MEMORY]; } } else if (nodes_allowed) { /* @@ -1401,11 +1625,11 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy, count += h->nr_huge_pages - h->nr_huge_pages_node[nid]; init_nodemask_of_node(nodes_allowed, nid); } else - nodes_allowed = &node_states[N_HIGH_MEMORY]; + nodes_allowed = &node_states[N_MEMORY]; h->max_huge_pages = set_max_huge_pages(h, count, nodes_allowed); - if (nodes_allowed != &node_states[N_HIGH_MEMORY]) + if (nodes_allowed != &node_states[N_MEMORY]) NODEMASK_FREE(nodes_allowed); return len; @@ -1465,7 +1689,7 @@ static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, if (h->order >= MAX_ORDER) return -EINVAL; - err = strict_strtoul(buf, 10, &input); + err = kstrtoul(buf, 10, &input); if (err) return err; @@ -1540,7 +1764,7 @@ static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent, struct attribute_group *hstate_attr_group) { int retval; - int hi = h - hstates; + int hi = hstate_index(h); hstate_kobjs[hi] = kobject_create_and_add(h->name, parent); if (!hstate_kobjs[hi]) @@ -1566,8 +1790,7 @@ static void __init hugetlb_sysfs_init(void) err = hugetlb_sysfs_add_hstate(h, hugepages_kobj, hstate_kobjs, &hstate_attr_group); if (err) - printk(KERN_ERR "Hugetlb: Unable to add hstate %s", - h->name); + pr_err("Hugetlb: Unable to add hstate %s", h->name); } } @@ -1575,9 +1798,9 @@ static void __init hugetlb_sysfs_init(void) /* * node_hstate/s - associate per node hstate attributes, via their kobjects, - * with node sysdevs in node_devices[] using a parallel array. The array - * index of a node sysdev or _hstate == node id. - * This is here to avoid any static dependency of the node sysdev driver, in + * with node devices in node_devices[] using a parallel array. The array + * index of a node device or _hstate == node id. + * This is here to avoid any static dependency of the node device driver, in * the base kernel, on the hugetlb module. */ struct node_hstate { @@ -1587,7 +1810,7 @@ struct node_hstate { struct node_hstate node_hstates[MAX_NUMNODES]; /* - * A subset of global hstate attributes for node sysdevs + * A subset of global hstate attributes for node devices */ static struct attribute *per_node_hstate_attrs[] = { &nr_hugepages_attr.attr, @@ -1601,7 +1824,7 @@ static struct attribute_group per_node_hstate_attr_group = { }; /* - * kobj_to_node_hstate - lookup global hstate for node sysdev hstate attr kobj. + * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj. * Returns node id via non-NULL nidp. */ static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) @@ -1624,29 +1847,31 @@ static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp) } /* - * Unregister hstate attributes from a single node sysdev. + * Unregister hstate attributes from a single node device. * No-op if no hstate attributes attached. */ -void hugetlb_unregister_node(struct node *node) +static void hugetlb_unregister_node(struct node *node) { struct hstate *h; - struct node_hstate *nhs = &node_hstates[node->sysdev.id]; + struct node_hstate *nhs = &node_hstates[node->dev.id]; if (!nhs->hugepages_kobj) return; /* no hstate attributes */ - for_each_hstate(h) - if (nhs->hstate_kobjs[h - hstates]) { - kobject_put(nhs->hstate_kobjs[h - hstates]); - nhs->hstate_kobjs[h - hstates] = NULL; + for_each_hstate(h) { + int idx = hstate_index(h); + if (nhs->hstate_kobjs[idx]) { + kobject_put(nhs->hstate_kobjs[idx]); + nhs->hstate_kobjs[idx] = NULL; } + } kobject_put(nhs->hugepages_kobj); nhs->hugepages_kobj = NULL; } /* - * hugetlb module exit: unregister hstate attributes from node sysdevs + * hugetlb module exit: unregister hstate attributes from node devices * that have them. */ static void hugetlb_unregister_all_nodes(void) @@ -1654,7 +1879,7 @@ static void hugetlb_unregister_all_nodes(void) int nid; /* - * disable node sysdev registrations. + * disable node device registrations. */ register_hugetlbfs_with_node(NULL, NULL); @@ -1662,24 +1887,24 @@ static void hugetlb_unregister_all_nodes(void) * remove hstate attributes from any nodes that have them. */ for (nid = 0; nid < nr_node_ids; nid++) - hugetlb_unregister_node(&node_devices[nid]); + hugetlb_unregister_node(node_devices[nid]); } /* - * Register hstate attributes for a single node sysdev. + * Register hstate attributes for a single node device. * No-op if attributes already registered. */ -void hugetlb_register_node(struct node *node) +static void hugetlb_register_node(struct node *node) { struct hstate *h; - struct node_hstate *nhs = &node_hstates[node->sysdev.id]; + struct node_hstate *nhs = &node_hstates[node->dev.id]; int err; if (nhs->hugepages_kobj) return; /* already allocated */ nhs->hugepages_kobj = kobject_create_and_add("hugepages", - &node->sysdev.kobj); + &node->dev.kobj); if (!nhs->hugepages_kobj) return; @@ -1688,9 +1913,8 @@ void hugetlb_register_node(struct node *node) nhs->hstate_kobjs, &per_node_hstate_attr_group); if (err) { - printk(KERN_ERR "Hugetlb: Unable to add hstate %s" - " for node %d\n", - h->name, node->sysdev.id); + pr_err("Hugetlb: Unable to add hstate %s for node %d\n", + h->name, node->dev.id); hugetlb_unregister_node(node); break; } @@ -1699,21 +1923,21 @@ void hugetlb_register_node(struct node *node) /* * hugetlb init time: register hstate attributes for all registered node - * sysdevs of nodes that have memory. All on-line nodes should have - * registered their associated sysdev by this time. + * devices of nodes that have memory. All on-line nodes should have + * registered their associated device by this time. */ static void hugetlb_register_all_nodes(void) { int nid; - for_each_node_state(nid, N_HIGH_MEMORY) { - struct node *node = &node_devices[nid]; - if (node->sysdev.id == nid) + for_each_node_state(nid, N_MEMORY) { + struct node *node = node_devices[nid]; + if (node->dev.id == nid) hugetlb_register_node(node); } /* - * Let the node sysdev driver know we're here so it can + * Let the node device driver know we're here so it can * [un]register hstate attributes on node hotplug. */ register_hugetlbfs_with_node(hugetlb_register_node, @@ -1742,7 +1966,7 @@ static void __exit hugetlb_exit(void) hugetlb_unregister_all_nodes(); for_each_hstate(h) { - kobject_put(hstate_kobjs[h - hstates]); + kobject_put(hstate_kobjs[hstate_index(h)]); } kobject_put(hugepages_kobj); @@ -1763,19 +1987,17 @@ static int __init hugetlb_init(void) if (!size_to_hstate(default_hstate_size)) hugetlb_add_hstate(HUGETLB_PAGE_ORDER); } - default_hstate_idx = size_to_hstate(default_hstate_size) - hstates; + default_hstate_idx = hstate_index(size_to_hstate(default_hstate_size)); if (default_hstate_max_huge_pages) default_hstate.max_huge_pages = default_hstate_max_huge_pages; hugetlb_init_hstates(); - gather_bootmem_prealloc(); - report_hugepages(); hugetlb_sysfs_init(); - hugetlb_register_all_nodes(); + hugetlb_cgroup_file_init(); return 0; } @@ -1788,20 +2010,21 @@ void __init hugetlb_add_hstate(unsigned order) unsigned long i; if (size_to_hstate(PAGE_SIZE << order)) { - printk(KERN_WARNING "hugepagesz= specified twice, ignoring\n"); + pr_warning("hugepagesz= specified twice, ignoring\n"); return; } - BUG_ON(max_hstate >= HUGE_MAX_HSTATE); + BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE); BUG_ON(order == 0); - h = &hstates[max_hstate++]; + h = &hstates[hugetlb_max_hstate++]; h->order = order; h->mask = ~((1ULL << (order + PAGE_SHIFT)) - 1); h->nr_huge_pages = 0; h->free_huge_pages = 0; for (i = 0; i < MAX_NUMNODES; ++i) INIT_LIST_HEAD(&h->hugepage_freelists[i]); - h->next_nid_to_alloc = first_node(node_states[N_HIGH_MEMORY]); - h->next_nid_to_free = first_node(node_states[N_HIGH_MEMORY]); + INIT_LIST_HEAD(&h->hugepage_activelist); + h->next_nid_to_alloc = first_node(node_states[N_MEMORY]); + h->next_nid_to_free = first_node(node_states[N_MEMORY]); snprintf(h->name, HSTATE_NAME_LEN, "hugepages-%lukB", huge_page_size(h)/1024); @@ -1814,17 +2037,17 @@ static int __init hugetlb_nrpages_setup(char *s) static unsigned long *last_mhp; /* - * !max_hstate means we haven't parsed a hugepagesz= parameter yet, + * !hugetlb_max_hstate means we haven't parsed a hugepagesz= parameter yet, * so this hugepages= parameter goes to the "default hstate". */ - if (!max_hstate) + if (!hugetlb_max_hstate) mhp = &default_hstate_max_huge_pages; else mhp = &parsed_hstate->max_huge_pages; if (mhp == last_mhp) { - printk(KERN_WARNING "hugepages= specified twice without " - "interleaving hugepagesz=, ignoring\n"); + pr_warning("hugepages= specified twice without " + "interleaving hugepagesz=, ignoring\n"); return 1; } @@ -1836,7 +2059,7 @@ static int __init hugetlb_nrpages_setup(char *s) * But we need to allocate >= MAX_ORDER hstates here early to still * use the bootmem allocator. */ - if (max_hstate && parsed_hstate->order >= MAX_ORDER) + if (hugetlb_max_hstate && parsed_hstate->order >= MAX_ORDER) hugetlb_hstate_alloc_pages(parsed_hstate); last_mhp = mhp; @@ -1872,8 +2095,7 @@ static int hugetlb_sysctl_handler_common(bool obey_mempolicy, unsigned long tmp; int ret; - if (!write) - tmp = h->max_huge_pages; + tmp = h->max_huge_pages; if (write && h->order >= MAX_ORDER) return -EINVAL; @@ -1890,11 +2112,11 @@ static int hugetlb_sysctl_handler_common(bool obey_mempolicy, if (!(obey_mempolicy && init_nodemask_of_mempolicy(nodes_allowed))) { NODEMASK_FREE(nodes_allowed); - nodes_allowed = &node_states[N_HIGH_MEMORY]; + nodes_allowed = &node_states[N_MEMORY]; } h->max_huge_pages = set_max_huge_pages(h, tmp, nodes_allowed); - if (nodes_allowed != &node_states[N_HIGH_MEMORY]) + if (nodes_allowed != &node_states[N_MEMORY]) NODEMASK_FREE(nodes_allowed); } out: @@ -1918,18 +2140,6 @@ int hugetlb_mempolicy_sysctl_handler(struct ctl_table *table, int write, } #endif /* CONFIG_NUMA */ -int hugetlb_treat_movable_handler(struct ctl_table *table, int write, - void __user *buffer, - size_t *length, loff_t *ppos) -{ - proc_dointvec(table, write, buffer, length, ppos); - if (hugepages_treat_as_movable) - htlb_alloc_mask = GFP_HIGHUSER_MOVABLE; - else - htlb_alloc_mask = GFP_HIGHUSER; - return 0; -} - int hugetlb_overcommit_handler(struct ctl_table *table, int write, void __user *buffer, size_t *length, loff_t *ppos) @@ -1938,8 +2148,7 @@ int hugetlb_overcommit_handler(struct ctl_table *table, int write, unsigned long tmp; int ret; - if (!write) - tmp = h->nr_overcommit_huge_pages; + tmp = h->nr_overcommit_huge_pages; if (write && h->order >= MAX_ORDER) return -EINVAL; @@ -1989,11 +2198,30 @@ int hugetlb_report_node_meminfo(int nid, char *buf) nid, h->surplus_huge_pages_node[nid]); } +void hugetlb_show_meminfo(void) +{ + struct hstate *h; + int nid; + + for_each_node_state(nid, N_MEMORY) + for_each_hstate(h) + pr_info("Node %d hugepages_total=%u hugepages_free=%u hugepages_surp=%u hugepages_size=%lukB\n", + nid, + h->nr_huge_pages_node[nid], + h->free_huge_pages_node[nid], + h->surplus_huge_pages_node[nid], + 1UL << (huge_page_order(h) + PAGE_SHIFT - 10)); +} + /* Return the number pages of memory we physically have, in PAGE_SIZE units. */ unsigned long hugetlb_total_pages(void) { - struct hstate *h = &default_hstate; - return h->nr_huge_pages * pages_per_huge_page(h); + struct hstate *h; + unsigned long nr_total_pages = 0; + + for_each_hstate(h) + nr_total_pages += h->nr_huge_pages * pages_per_huge_page(h); + return nr_total_pages; } static int hugetlb_acct_memory(struct hstate *h, long delta) @@ -2039,40 +2267,50 @@ out: static void hugetlb_vm_op_open(struct vm_area_struct *vma) { - struct resv_map *reservations = vma_resv_map(vma); + struct resv_map *resv = vma_resv_map(vma); /* * This new VMA should share its siblings reservation map if present. * The VMA will only ever have a valid reservation map pointer where * it is being copied for another still existing VMA. As that VMA - * has a reference to the reservation map it cannot dissappear until + * has a reference to the reservation map it cannot disappear until * after this open call completes. It is therefore safe to take a * new reference here without additional locking. */ - if (reservations) - kref_get(&reservations->refs); + if (resv) + kref_get(&resv->refs); +} + +static void resv_map_put(struct vm_area_struct *vma) +{ + struct resv_map *resv = vma_resv_map(vma); + + if (!resv) + return; + kref_put(&resv->refs, resv_map_release); } static void hugetlb_vm_op_close(struct vm_area_struct *vma) { struct hstate *h = hstate_vma(vma); - struct resv_map *reservations = vma_resv_map(vma); + struct resv_map *resv = vma_resv_map(vma); + struct hugepage_subpool *spool = subpool_vma(vma); unsigned long reserve; unsigned long start; unsigned long end; - if (reservations) { + if (resv) { start = vma_hugecache_offset(h, vma, vma->vm_start); end = vma_hugecache_offset(h, vma, vma->vm_end); reserve = (end - start) - - region_count(&reservations->regions, start, end); + region_count(&resv->regions, start, end); - kref_put(&reservations->refs, resv_map_release); + resv_map_put(vma); if (reserve) { hugetlb_acct_memory(h, -reserve); - hugetlb_put_quota(vma->vm_file->f_mapping, reserve); + hugepage_subpool_put_pages(spool, reserve); } } } @@ -2101,13 +2339,15 @@ static pte_t make_huge_pte(struct vm_area_struct *vma, struct page *page, pte_t entry; if (writable) { - entry = - pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot))); + entry = huge_pte_mkwrite(huge_pte_mkdirty(mk_huge_pte(page, + vma->vm_page_prot))); } else { - entry = huge_pte_wrprotect(mk_pte(page, vma->vm_page_prot)); + entry = huge_pte_wrprotect(mk_huge_pte(page, + vma->vm_page_prot)); } entry = pte_mkyoung(entry); entry = pte_mkhuge(entry); + entry = arch_make_huge_pte(entry, vma, page, writable); return entry; } @@ -2117,10 +2357,9 @@ static void set_huge_ptep_writable(struct vm_area_struct *vma, { pte_t entry; - entry = pte_mkwrite(pte_mkdirty(huge_ptep_get(ptep))); - if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) { + entry = huge_pte_mkwrite(huge_pte_mkdirty(huge_ptep_get(ptep))); + if (huge_ptep_set_access_flags(vma, address, ptep, entry, 1)) update_mmu_cache(vma, address, ptep); - } } @@ -2175,9 +2414,9 @@ static int is_hugetlb_entry_migration(pte_t pte) if (huge_pte_none(pte) || pte_present(pte)) return 0; swp = pte_to_swp_entry(pte); - if (non_swap_entry(swp) && is_migration_entry(swp)) { + if (non_swap_entry(swp) && is_migration_entry(swp)) return 1; - } else + else return 0; } @@ -2188,36 +2427,34 @@ static int is_hugetlb_entry_hwpoisoned(pte_t pte) if (huge_pte_none(pte) || pte_present(pte)) return 0; swp = pte_to_swp_entry(pte); - if (non_swap_entry(swp) && is_hwpoison_entry(swp)) { + if (non_swap_entry(swp) && is_hwpoison_entry(swp)) return 1; - } else + else return 0; } -void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, - unsigned long end, struct page *ref_page) +void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma, + unsigned long start, unsigned long end, + struct page *ref_page) { + int force_flush = 0; struct mm_struct *mm = vma->vm_mm; unsigned long address; pte_t *ptep; pte_t pte; struct page *page; - struct page *tmp; struct hstate *h = hstate_vma(vma); unsigned long sz = huge_page_size(h); - - /* - * A page gathering list, protected by per file i_mmap_lock. The - * lock is used to avoid list corruption from multiple unmapping - * of the same page since we are using page->lru. - */ - LIST_HEAD(page_list); + const unsigned long mmun_start = start; /* For mmu_notifiers */ + const unsigned long mmun_end = end; /* For mmu_notifiers */ WARN_ON(!is_vm_hugetlb_page(vma)); BUG_ON(start & ~huge_page_mask(h)); BUG_ON(end & ~huge_page_mask(h)); - mmu_notifier_invalidate_range_start(mm, start, end); + tlb_start_vma(tlb, vma); + mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); +again: spin_lock(&mm->page_table_lock); for (address = start; address < end; address += sz) { ptep = huge_pte_offset(mm, address); @@ -2227,16 +2464,25 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, if (huge_pmd_unshare(mm, &address, ptep)) continue; + pte = huge_ptep_get(ptep); + if (huge_pte_none(pte)) + continue; + + /* + * HWPoisoned hugepage is already unmapped and dropped reference + */ + if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { + huge_pte_clear(mm, address, ptep); + continue; + } + + page = pte_page(pte); /* * If a reference page is supplied, it is because a specific * page is being unmapped, not a range. Ensure the page we * are about to unmap is the actual page of interest. */ if (ref_page) { - pte = huge_ptep_get(ptep); - if (huge_pte_none(pte)) - continue; - page = pte_page(pte); if (page != ref_page) continue; @@ -2249,36 +2495,64 @@ void __unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, } pte = huge_ptep_get_and_clear(mm, address, ptep); - if (huge_pte_none(pte)) - continue; - - /* - * HWPoisoned hugepage is already unmapped and dropped reference - */ - if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) - continue; - - page = pte_page(pte); - if (pte_dirty(pte)) + tlb_remove_tlb_entry(tlb, ptep, address); + if (huge_pte_dirty(pte)) set_page_dirty(page); - list_add(&page->lru, &page_list); + + page_remove_rmap(page); + force_flush = !__tlb_remove_page(tlb, page); + if (force_flush) + break; + /* Bail out after unmapping reference page if supplied */ + if (ref_page) + break; } spin_unlock(&mm->page_table_lock); - flush_tlb_range(vma, start, end); - mmu_notifier_invalidate_range_end(mm, start, end); - list_for_each_entry_safe(page, tmp, &page_list, lru) { - page_remove_rmap(page); - list_del(&page->lru); - put_page(page); + /* + * mmu_gather ran out of room to batch pages, we break out of + * the PTE lock to avoid doing the potential expensive TLB invalidate + * and page-free while holding it. + */ + if (force_flush) { + force_flush = 0; + tlb_flush_mmu(tlb); + if (address < end && !ref_page) + goto again; } + mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); + tlb_end_vma(tlb, vma); +} + +void __unmap_hugepage_range_final(struct mmu_gather *tlb, + struct vm_area_struct *vma, unsigned long start, + unsigned long end, struct page *ref_page) +{ + __unmap_hugepage_range(tlb, vma, start, end, ref_page); + + /* + * Clear this flag so that x86's huge_pmd_share page_table_shareable + * test will fail on a vma being torn down, and not grab a page table + * on its way out. We're lucky that the flag has such an appropriate + * name, and can in fact be safely cleared here. We could clear it + * before the __unmap_hugepage_range above, but all that's necessary + * is to clear it before releasing the i_mmap_mutex. This works + * because in the context this is called, the VMA is about to be + * destroyed and the i_mmap_mutex is held. + */ + vma->vm_flags &= ~VM_MAYSHARE; } void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, unsigned long end, struct page *ref_page) { - spin_lock(&vma->vm_file->f_mapping->i_mmap_lock); - __unmap_hugepage_range(vma, start, end, ref_page); - spin_unlock(&vma->vm_file->f_mapping->i_mmap_lock); + struct mm_struct *mm; + struct mmu_gather tlb; + + mm = vma->vm_mm; + + tlb_gather_mmu(&tlb, mm, start, end); + __unmap_hugepage_range(&tlb, vma, start, end, ref_page); + tlb_finish_mmu(&tlb, start, end); } /* @@ -2293,7 +2567,6 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, struct hstate *h = hstate_vma(vma); struct vm_area_struct *iter_vma; struct address_space *mapping; - struct prio_tree_iter iter; pgoff_t pgoff; /* @@ -2301,17 +2574,17 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, * from page cache lookup which is in HPAGE_SIZE units. */ address = address & huge_page_mask(h); - pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) - + (vma->vm_pgoff >> PAGE_SHIFT); - mapping = (struct address_space *)page_private(page); + pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + + vma->vm_pgoff; + mapping = file_inode(vma->vm_file)->i_mapping; /* * Take the mapping lock for the duration of the table walk. As * this mapping should be shared between all the VMAs, * __unmap_hugepage_range() is called as the lock is already held */ - spin_lock(&mapping->i_mmap_lock); - vma_prio_tree_foreach(iter_vma, &iter, &mapping->i_mmap, pgoff, pgoff) { + mutex_lock(&mapping->i_mmap_mutex); + vma_interval_tree_foreach(iter_vma, &mapping->i_mmap, pgoff, pgoff) { /* Do not unmap the current VMA */ if (iter_vma == vma) continue; @@ -2324,17 +2597,19 @@ static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, * from the time of fork. This would look like data corruption */ if (!is_vma_resv_set(iter_vma, HPAGE_RESV_OWNER)) - __unmap_hugepage_range(iter_vma, - address, address + huge_page_size(h), - page); + unmap_hugepage_range(iter_vma, address, + address + huge_page_size(h), page); } - spin_unlock(&mapping->i_mmap_lock); + mutex_unlock(&mapping->i_mmap_mutex); return 1; } /* * Hugetlb_cow() should be called with page lock of the original hugepage held. + * Called with hugetlb_instantiation_mutex held and pte_page locked so we + * cannot race with other handlers or page migration. + * Keep the pte_same checks anyway to make transition from the mutex easier. */ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, pte_t *ptep, pte_t pte, @@ -2342,18 +2617,17 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma, { struct hstate *h = hstate_vma(vma); struct page *old_page, *new_page; - int avoidcopy; int outside_reserve = 0; + unsigned long mmun_start; /* For mmu_notifiers */ + unsigned long mmun_end; /* For mmu_notifiers */ old_page = pte_page(pte); retry_avoidcopy: /* If no-one else is actually using this page, avoid the copy * and just make the page writable */ - avoidcopy = (page_mapcount(old_page) == 1); - if (avoidcopy) { - if (PageAnon(old_page)) - page_move_anon_rmap(old_page, vma, address); + if (page_mapcount(old_page) == 1 && PageAnon(old_page)) { + page_move_anon_rmap(old_page, vma, address); set_huge_ptep_writable(vma, address, ptep); return 0; } @@ -2367,8 +2641,7 @@ retry_avoidcopy: * at the time of fork() could consume its reserves on COW instead * of the full address range. */ - if (!(vma->vm_flags & VM_MAYSHARE) && - is_vma_resv_set(vma, HPAGE_RESV_OWNER) && + if (is_vma_resv_set(vma, HPAGE_RESV_OWNER) && old_page != pagecache_page) outside_reserve = 1; @@ -2379,6 +2652,7 @@ retry_avoidcopy: new_page = alloc_huge_page(vma, address, outside_reserve); if (IS_ERR(new_page)) { + long err = PTR_ERR(new_page); page_cache_release(old_page); /* @@ -2391,17 +2665,26 @@ retry_avoidcopy: if (outside_reserve) { BUG_ON(huge_pte_none(pte)); if (unmap_ref_private(mm, vma, old_page, address)) { - BUG_ON(page_count(old_page) != 1); BUG_ON(huge_pte_none(pte)); spin_lock(&mm->page_table_lock); - goto retry_avoidcopy; + ptep = huge_pte_offset(mm, address & huge_page_mask(h)); + if (likely(pte_same(huge_ptep_get(ptep), pte))) + goto retry_avoidcopy; + /* + * race occurs while re-acquiring page_table_lock, and + * our job is done. + */ + return 0; } WARN_ON_ONCE(1); } /* Caller expects lock to be held */ spin_lock(&mm->page_table_lock); - return -PTR_ERR(new_page); + if (err == -ENOMEM) + return VM_FAULT_OOM; + else + return VM_FAULT_SIGBUS; } /* @@ -2409,6 +2692,8 @@ retry_avoidcopy: * anon_vma prepared. */ if (unlikely(anon_vma_prepare(vma))) { + page_cache_release(new_page); + page_cache_release(old_page); /* Caller expects lock to be held */ spin_lock(&mm->page_table_lock); return VM_FAULT_OOM; @@ -2418,6 +2703,9 @@ retry_avoidcopy: pages_per_huge_page(h)); __SetPageUptodate(new_page); + mmun_start = address & huge_page_mask(h); + mmun_end = mmun_start + huge_page_size(h); + mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); /* * Retake the page_table_lock to check for racing updates * before the page tables are altered @@ -2425,10 +2713,9 @@ retry_avoidcopy: spin_lock(&mm->page_table_lock); ptep = huge_pte_offset(mm, address & huge_page_mask(h)); if (likely(pte_same(huge_ptep_get(ptep), pte))) { + ClearPagePrivate(new_page); + /* Break COW */ - mmu_notifier_invalidate_range_start(mm, - address & huge_page_mask(h), - (address & huge_page_mask(h)) + huge_page_size(h)); huge_ptep_clear_flush(vma, address, ptep); set_huge_pte_at(mm, address, ptep, make_huge_pte(vma, new_page, 1)); @@ -2436,12 +2723,14 @@ retry_avoidcopy: hugepage_add_new_anon_rmap(new_page, vma, address); /* Make the old page be freed below */ new_page = old_page; - mmu_notifier_invalidate_range_end(mm, - address & huge_page_mask(h), - (address & huge_page_mask(h)) + huge_page_size(h)); } + spin_unlock(&mm->page_table_lock); + mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); page_cache_release(new_page); page_cache_release(old_page); + + /* Caller expects lock to be held */ + spin_lock(&mm->page_table_lock); return 0; } @@ -2483,6 +2772,7 @@ static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma, { struct hstate *h = hstate_vma(vma); int ret = VM_FAULT_SIGBUS; + int anon_rmap = 0; pgoff_t idx; unsigned long size; struct page *page; @@ -2492,12 +2782,11 @@ static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma, /* * Currently, we are forced to kill the process in the event the * original mapper has unmapped pages from the child due to a failed - * COW. Warn that such a situation has occured as it may not be obvious + * COW. Warn that such a situation has occurred as it may not be obvious */ if (is_vma_resv_set(vma, HPAGE_RESV_UNMAPPED)) { - printk(KERN_WARNING - "PID %d killed due to inadequate hugepage pool\n", - current->pid); + pr_warning("PID %d killed due to inadequate hugepage pool\n", + current->pid); return ret; } @@ -2516,7 +2805,11 @@ retry: goto out; page = alloc_huge_page(vma, address, 0); if (IS_ERR(page)) { - ret = -PTR_ERR(page); + ret = PTR_ERR(page); + if (ret == -ENOMEM) + ret = VM_FAULT_OOM; + else + ret = VM_FAULT_SIGBUS; goto out; } clear_huge_page(page, address, pages_per_huge_page(h)); @@ -2533,18 +2826,18 @@ retry: goto retry; goto out; } + ClearPagePrivate(page); spin_lock(&inode->i_lock); inode->i_blocks += blocks_per_huge_page(h); spin_unlock(&inode->i_lock); - page_dup_rmap(page); } else { lock_page(page); if (unlikely(anon_vma_prepare(vma))) { ret = VM_FAULT_OOM; goto backout_unlocked; } - hugepage_add_new_anon_rmap(page, vma, address); + anon_rmap = 1; } } else { /* @@ -2553,11 +2846,10 @@ retry: * So we need to block hugepage fault by PG_hwpoison bit check. */ if (unlikely(PageHWPoison(page))) { - ret = VM_FAULT_HWPOISON | - VM_FAULT_SET_HINDEX(h - hstates); + ret = VM_FAULT_HWPOISON | + VM_FAULT_SET_HINDEX(hstate_index(h)); goto backout_unlocked; } - page_dup_rmap(page); } /* @@ -2581,6 +2873,12 @@ retry: if (!huge_pte_none(huge_ptep_get(ptep))) goto backout; + if (anon_rmap) { + ClearPagePrivate(page); + hugepage_add_new_anon_rmap(page, vma, address); + } + else + page_dup_rmap(page); new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) && (vma->vm_flags & VM_SHARED))); set_huge_pte_at(mm, address, ptep, new_pte); @@ -2614,15 +2912,17 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, static DEFINE_MUTEX(hugetlb_instantiation_mutex); struct hstate *h = hstate_vma(vma); + address &= huge_page_mask(h); + ptep = huge_pte_offset(mm, address); if (ptep) { entry = huge_ptep_get(ptep); if (unlikely(is_hugetlb_entry_migration(entry))) { - migration_entry_wait(mm, (pmd_t *)ptep, address); + migration_entry_wait_huge(mm, ptep); return 0; } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) - return VM_FAULT_HWPOISON_LARGE | - VM_FAULT_SET_HINDEX(h - hstates); + return VM_FAULT_HWPOISON_LARGE | + VM_FAULT_SET_HINDEX(hstate_index(h)); } ptep = huge_pte_alloc(mm, address, huge_page_size(h)); @@ -2651,7 +2951,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, * page now as it is used to determine if a reservation has been * consumed. */ - if ((flags & FAULT_FLAG_WRITE) && !pte_write(entry)) { + if ((flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) { if (vma_needs_reservation(h, vma, address) < 0) { ret = VM_FAULT_OOM; goto out_mutex; @@ -2670,6 +2970,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, * so no worry about deadlock. */ page = pte_page(entry); + get_page(page); if (page != pagecache_page) lock_page(page); @@ -2680,12 +2981,12 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, if (flags & FAULT_FLAG_WRITE) { - if (!pte_write(entry)) { + if (!huge_pte_write(entry)) { ret = hugetlb_cow(mm, vma, address, ptep, entry, pagecache_page); goto out_page_table_lock; } - entry = pte_mkdirty(entry); + entry = huge_pte_mkdirty(entry); } entry = pte_mkyoung(entry); if (huge_ptep_set_access_flags(vma, address, ptep, entry, @@ -2701,6 +3002,7 @@ out_page_table_lock: } if (page != pagecache_page) unlock_page(page); + put_page(page); out_mutex: mutex_unlock(&hugetlb_instantiation_mutex); @@ -2708,23 +3010,14 @@ out_mutex: return ret; } -/* Can be overriden by architectures */ -__attribute__((weak)) struct page * -follow_huge_pud(struct mm_struct *mm, unsigned long address, - pud_t *pud, int write) -{ - BUG(); - return NULL; -} - -int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, - struct page **pages, struct vm_area_struct **vmas, - unsigned long *position, int *length, int i, - unsigned int flags) +long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, + struct page **pages, struct vm_area_struct **vmas, + unsigned long *position, unsigned long *nr_pages, + long i, unsigned int flags) { unsigned long pfn_offset; unsigned long vaddr = *position; - int remainder = *length; + unsigned long remainder = *nr_pages; struct hstate *h = hstate_vma(vma); spin_lock(&mm->page_table_lock); @@ -2754,8 +3047,19 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, break; } - if (absent || - ((flags & FOLL_WRITE) && !pte_write(huge_ptep_get(pte)))) { + /* + * We need call hugetlb_fault for both hugepages under migration + * (in which case hugetlb_fault waits for the migration,) and + * hwpoisoned hugepages (in which case we need to prevent the + * caller from accessing to them.) In order to do this, we use + * here is_swap_pte instead of is_hugetlb_entry_migration and + * is_hugetlb_entry_hwpoisoned. This is because it simply covers + * both cases, and because we can't follow correct pages + * directly from any kind of swap entries. + */ + if (absent || is_swap_pte(huge_ptep_get(pte)) || + ((flags & FOLL_WRITE) && + !huge_pte_write(huge_ptep_get(pte)))) { int ret; spin_unlock(&mm->page_table_lock); @@ -2794,13 +3098,13 @@ same_page: } } spin_unlock(&mm->page_table_lock); - *length = remainder; + *nr_pages = remainder; *position = vaddr; return i ? i : -EFAULT; } -void hugetlb_change_protection(struct vm_area_struct *vma, +unsigned long hugetlb_change_protection(struct vm_area_struct *vma, unsigned long address, unsigned long end, pgprot_t newprot) { struct mm_struct *mm = vma->vm_mm; @@ -2808,44 +3112,57 @@ void hugetlb_change_protection(struct vm_area_struct *vma, pte_t *ptep; pte_t pte; struct hstate *h = hstate_vma(vma); + unsigned long pages = 0; BUG_ON(address >= end); flush_cache_range(vma, address, end); - spin_lock(&vma->vm_file->f_mapping->i_mmap_lock); + mutex_lock(&vma->vm_file->f_mapping->i_mmap_mutex); spin_lock(&mm->page_table_lock); for (; address < end; address += huge_page_size(h)) { ptep = huge_pte_offset(mm, address); if (!ptep) continue; - if (huge_pmd_unshare(mm, &address, ptep)) + if (huge_pmd_unshare(mm, &address, ptep)) { + pages++; continue; + } if (!huge_pte_none(huge_ptep_get(ptep))) { pte = huge_ptep_get_and_clear(mm, address, ptep); - pte = pte_mkhuge(pte_modify(pte, newprot)); + pte = pte_mkhuge(huge_pte_modify(pte, newprot)); + pte = arch_make_huge_pte(pte, vma, NULL, 0); set_huge_pte_at(mm, address, ptep, pte); + pages++; } } spin_unlock(&mm->page_table_lock); - spin_unlock(&vma->vm_file->f_mapping->i_mmap_lock); - + /* + * Must flush TLB before releasing i_mmap_mutex: x86's huge_pmd_unshare + * may have cleared our pud entry and done put_page on the page table: + * once we release i_mmap_mutex, another task can do the final put_page + * and that page table be reused and filled with junk. + */ flush_tlb_range(vma, start, end); + mutex_unlock(&vma->vm_file->f_mapping->i_mmap_mutex); + + return pages << h->order; } int hugetlb_reserve_pages(struct inode *inode, long from, long to, struct vm_area_struct *vma, - int acctflag) + vm_flags_t vm_flags) { long ret, chg; struct hstate *h = hstate_inode(inode); + struct hugepage_subpool *spool = subpool_inode(inode); /* * Only apply hugepage reservation if asked. At fault time, an * attempt will be made for VM_NORESERVE to allocate a page - * and filesystem quota without using reserves + * without using reserves */ - if (acctflag & VM_NORESERVE) + if (vm_flags & VM_NORESERVE) return 0; /* @@ -2867,21 +3184,25 @@ int hugetlb_reserve_pages(struct inode *inode, set_vma_resv_flags(vma, HPAGE_RESV_OWNER); } - if (chg < 0) - return chg; + if (chg < 0) { + ret = chg; + goto out_err; + } - /* There must be enough filesystem quota for the mapping */ - if (hugetlb_get_quota(inode->i_mapping, chg)) - return -ENOSPC; + /* There must be enough pages in the subpool for the mapping */ + if (hugepage_subpool_get_pages(spool, chg)) { + ret = -ENOSPC; + goto out_err; + } /* * Check enough hugepages are available for the reservation. - * Hand back the quota if there are not + * Hand the pages back to the subpool if there are not */ ret = hugetlb_acct_memory(h, chg); if (ret < 0) { - hugetlb_put_quota(inode->i_mapping, chg); - return ret; + hugepage_subpool_put_pages(spool, chg); + goto out_err; } /* @@ -2898,21 +3219,236 @@ int hugetlb_reserve_pages(struct inode *inode, if (!vma || vma->vm_flags & VM_MAYSHARE) region_add(&inode->i_mapping->private_list, from, to); return 0; +out_err: + if (vma) + resv_map_put(vma); + return ret; } void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed) { struct hstate *h = hstate_inode(inode); long chg = region_truncate(&inode->i_mapping->private_list, offset); + struct hugepage_subpool *spool = subpool_inode(inode); spin_lock(&inode->i_lock); inode->i_blocks -= (blocks_per_huge_page(h) * freed); spin_unlock(&inode->i_lock); - hugetlb_put_quota(inode->i_mapping, (chg - freed)); + hugepage_subpool_put_pages(spool, (chg - freed)); hugetlb_acct_memory(h, -(chg - freed)); } +#ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE +static unsigned long page_table_shareable(struct vm_area_struct *svma, + struct vm_area_struct *vma, + unsigned long addr, pgoff_t idx) +{ + unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) + + svma->vm_start; + unsigned long sbase = saddr & PUD_MASK; + unsigned long s_end = sbase + PUD_SIZE; + + /* Allow segments to share if only one is marked locked */ + unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED; + unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED; + + /* + * match the virtual addresses, permission and the alignment of the + * page table page. + */ + if (pmd_index(addr) != pmd_index(saddr) || + vm_flags != svm_flags || + sbase < svma->vm_start || svma->vm_end < s_end) + return 0; + + return saddr; +} + +static int vma_shareable(struct vm_area_struct *vma, unsigned long addr) +{ + unsigned long base = addr & PUD_MASK; + unsigned long end = base + PUD_SIZE; + + /* + * check on proper vm_flags and page table alignment + */ + if (vma->vm_flags & VM_MAYSHARE && + vma->vm_start <= base && end <= vma->vm_end) + return 1; + return 0; +} + +/* + * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() + * and returns the corresponding pte. While this is not necessary for the + * !shared pmd case because we can allocate the pmd later as well, it makes the + * code much cleaner. pmd allocation is essential for the shared case because + * pud has to be populated inside the same i_mmap_mutex section - otherwise + * racing tasks could either miss the sharing (see huge_pte_offset) or select a + * bad pmd for sharing. + */ +pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) +{ + struct vm_area_struct *vma = find_vma(mm, addr); + struct address_space *mapping = vma->vm_file->f_mapping; + pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + + vma->vm_pgoff; + struct vm_area_struct *svma; + unsigned long saddr; + pte_t *spte = NULL; + pte_t *pte; + + if (!vma_shareable(vma, addr)) + return (pte_t *)pmd_alloc(mm, pud, addr); + + mutex_lock(&mapping->i_mmap_mutex); + vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { + if (svma == vma) + continue; + + saddr = page_table_shareable(svma, vma, addr, idx); + if (saddr) { + spte = huge_pte_offset(svma->vm_mm, saddr); + if (spte) { + get_page(virt_to_page(spte)); + break; + } + } + } + + if (!spte) + goto out; + + spin_lock(&mm->page_table_lock); + if (pud_none(*pud)) + pud_populate(mm, pud, + (pmd_t *)((unsigned long)spte & PAGE_MASK)); + else + put_page(virt_to_page(spte)); + spin_unlock(&mm->page_table_lock); +out: + pte = (pte_t *)pmd_alloc(mm, pud, addr); + mutex_unlock(&mapping->i_mmap_mutex); + return pte; +} + +/* + * unmap huge page backed by shared pte. + * + * Hugetlb pte page is ref counted at the time of mapping. If pte is shared + * indicated by page_count > 1, unmap is achieved by clearing pud and + * decrementing the ref count. If count == 1, the pte page is not shared. + * + * called with vma->vm_mm->page_table_lock held. + * + * returns: 1 successfully unmapped a shared pte page + * 0 the underlying pte page is not shared, or it is the last user + */ +int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) +{ + pgd_t *pgd = pgd_offset(mm, *addr); + pud_t *pud = pud_offset(pgd, *addr); + + BUG_ON(page_count(virt_to_page(ptep)) == 0); + if (page_count(virt_to_page(ptep)) == 1) + return 0; + + pud_clear(pud); + put_page(virt_to_page(ptep)); + *addr = ALIGN(*addr, HPAGE_SIZE * PTRS_PER_PTE) - HPAGE_SIZE; + return 1; +} +#define want_pmd_share() (1) +#else /* !CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ +pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) +{ + return NULL; +} +#define want_pmd_share() (0) +#endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ + +#ifdef CONFIG_ARCH_WANT_GENERAL_HUGETLB +pte_t *huge_pte_alloc(struct mm_struct *mm, + unsigned long addr, unsigned long sz) +{ + pgd_t *pgd; + pud_t *pud; + pte_t *pte = NULL; + + pgd = pgd_offset(mm, addr); + pud = pud_alloc(mm, pgd, addr); + if (pud) { + if (sz == PUD_SIZE) { + pte = (pte_t *)pud; + } else { + BUG_ON(sz != PMD_SIZE); + if (want_pmd_share() && pud_none(*pud)) + pte = huge_pmd_share(mm, addr, pud); + else + pte = (pte_t *)pmd_alloc(mm, pud, addr); + } + } + BUG_ON(pte && !pte_none(*pte) && !pte_huge(*pte)); + + return pte; +} + +pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd = NULL; + + pgd = pgd_offset(mm, addr); + if (pgd_present(*pgd)) { + pud = pud_offset(pgd, addr); + if (pud_present(*pud)) { + if (pud_huge(*pud)) + return (pte_t *)pud; + pmd = pmd_offset(pud, addr); + } + } + return (pte_t *) pmd; +} + +struct page * +follow_huge_pmd(struct mm_struct *mm, unsigned long address, + pmd_t *pmd, int write) +{ + struct page *page; + + page = pte_page(*(pte_t *)pmd); + if (page) + page += ((address & ~PMD_MASK) >> PAGE_SHIFT); + return page; +} + +struct page * +follow_huge_pud(struct mm_struct *mm, unsigned long address, + pud_t *pud, int write) +{ + struct page *page; + + page = pte_page(*(pte_t *)pud); + if (page) + page += ((address & ~PUD_MASK) >> PAGE_SHIFT); + return page; +} + +#else /* !CONFIG_ARCH_WANT_GENERAL_HUGETLB */ + +/* Can be overriden by architectures */ +__attribute__((weak)) struct page * +follow_huge_pud(struct mm_struct *mm, unsigned long address, + pud_t *pud, int write) +{ + BUG(); + return NULL; +} + +#endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */ + #ifdef CONFIG_MEMORY_FAILURE /* Should be called in hugetlb_lock */ @@ -2941,7 +3477,13 @@ int dequeue_hwpoisoned_huge_page(struct page *hpage) spin_lock(&hugetlb_lock); if (is_hugepage_on_freelist(hpage)) { - list_del(&hpage->lru); + /* + * Hwpoisoned hugepage isn't linked to activelist or freelist, + * but dangling hpage->lru can trigger list-debug warnings + * (this happens when we call unpoison_memory() on it), + * so let it point to itself with list_del_init(). + */ + list_del_init(&hpage->lru); set_page_refcounted(hpage); h->free_huge_pages--; h->free_huge_pages_node[nid]--; @@ -2951,3 +3493,45 @@ int dequeue_hwpoisoned_huge_page(struct page *hpage) return ret; } #endif + +bool isolate_huge_page(struct page *page, struct list_head *list) +{ + VM_BUG_ON(!PageHead(page)); + if (!get_page_unless_zero(page)) + return false; + spin_lock(&hugetlb_lock); + list_move_tail(&page->lru, list); + spin_unlock(&hugetlb_lock); + return true; +} + +void putback_active_hugepage(struct page *page) +{ + VM_BUG_ON(!PageHead(page)); + spin_lock(&hugetlb_lock); + list_move_tail(&page->lru, &(page_hstate(page))->hugepage_activelist); + spin_unlock(&hugetlb_lock); + put_page(page); +} + +bool is_hugepage_active(struct page *page) +{ + VM_BUG_ON(!PageHuge(page)); + /* + * This function can be called for a tail page because the caller, + * scan_movable_pages, scans through a given pfn-range which typically + * covers one memory block. In systems using gigantic hugepage (1GB + * for x86_64,) a hugepage is larger than a memory block, and we don't + * support migrating such large hugepages for now, so return false + * when called for tail pages. + */ + if (PageTail(page)) + return false; + /* + * Refcount of a hwpoisoned hugepages is 1, but they are not active, + * so we should return false for them. + */ + if (unlikely(PageHWPoison(page))) + return false; + return page_count(page) > 0; +} |