diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h index 2704729777ef..96e970485b6c 100644 --- a/include/linux/mm_inline.h +++ b/include/linux/mm_inline.h @@ -1,3 +1,28 @@ +#ifndef LINUX_MM_INLINE_H +#define LINUX_MM_INLINE_H + +/** + * page_is_file_cache - should the page be on a file LRU or anon LRU? + * @page: the page to test + * + * Returns !0 if @page is page cache page backed by a regular filesystem, + * or 0 if @page is anonymous, tmpfs or otherwise ram or swap backed. + * Used by functions that manipulate the LRU lists, to sort a page + * onto the right LRU list. + * + * We would like to get this info without a page flag, but the state + * needs to survive until the page is last deleted from the LRU, which + * could be as far down as __page_cache_release. + */ +static inline int page_is_file_cache(struct page *page) +{ + if (PageSwapBacked(page)) + return 0; + + /* The page is page cache backed by a normal filesystem. */ + return 1; +} + static inline void add_page_to_lru_list(struct zone *zone, struct page *page, enum lru_list l) { @@ -65,3 +90,5 @@ static inline enum lru_list page_lru(struct page *page) return lru; } + +#endif diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index c74d3e875314..57b688cfb5e2 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -93,6 +93,7 @@ enum pageflags { PG_mappedtodisk, /* Has blocks allocated on-disk */ PG_reclaim, /* To be reclaimed asap */ PG_buddy, /* Page is free, on buddy lists */ + PG_swapbacked, /* Page is backed by RAM/swap */ #ifdef CONFIG_IA64_UNCACHED_ALLOCATOR PG_uncached, /* Page has been mapped as uncached */ #endif @@ -176,6 +177,7 @@ PAGEFLAG(SavePinned, savepinned); /* Xen */ PAGEFLAG(Reserved, reserved) __CLEARPAGEFLAG(Reserved, reserved) PAGEFLAG(Private, private) __CLEARPAGEFLAG(Private, private) __SETPAGEFLAG(Private, private) +PAGEFLAG(SwapBacked, swapbacked) __CLEARPAGEFLAG(SwapBacked, swapbacked) __PAGEFLAG(SlobPage, slob_page) __PAGEFLAG(SlobFree, slob_free) @@ -334,7 +336,8 @@ static inline void __ClearPageTail(struct page *page) * Flags checked in bad_page(). Pages on the free list should not have * these flags set. It they are, there is a problem. */ -#define PAGE_FLAGS_CLEAR_WHEN_BAD (PAGE_FLAGS | 1 << PG_reclaim | 1 << PG_dirty) +#define PAGE_FLAGS_CLEAR_WHEN_BAD (PAGE_FLAGS | \ + 1 << PG_reclaim | 1 << PG_dirty | 1 << PG_swapbacked) /* * Flags checked when a page is freed. Pages being freed should not have @@ -347,7 +350,8 @@ static inline void __ClearPageTail(struct page *page) * Pages being prepped should not have these flags set. It they are, there * is a problem. */ -#define PAGE_FLAGS_CHECK_AT_PREP (PAGE_FLAGS | 1 << PG_reserved | 1 << PG_dirty) +#define PAGE_FLAGS_CHECK_AT_PREP (PAGE_FLAGS | \ + 1 << PG_reserved | 1 << PG_dirty | 1 << PG_swapbacked) #endif /* !__GENERATING_BOUNDS_H */ #endif /* PAGE_FLAGS_H */ diff --git a/mm/memory.c b/mm/memory.c index 1002f473f497..7512933dcc10 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1888,6 +1888,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, ptep_clear_flush_notify(vma, address, page_table); set_pte_at(mm, address, page_table, entry); update_mmu_cache(vma, address, entry); + SetPageSwapBacked(new_page); lru_cache_add_active(new_page); page_add_new_anon_rmap(new_page, vma, address); @@ -2382,6 +2383,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, if (!pte_none(*page_table)) goto release; inc_mm_counter(mm, anon_rss); + SetPageSwapBacked(page); lru_cache_add_active(page); page_add_new_anon_rmap(page, vma, address); set_pte_at(mm, address, page_table, entry); @@ -2523,6 +2525,7 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma, set_pte_at(mm, address, page_table, entry); if (anon) { inc_mm_counter(mm, anon_rss); + SetPageSwapBacked(page); lru_cache_add_active(page); page_add_new_anon_rmap(page, vma, address); } else { diff --git a/mm/migrate.c b/mm/migrate.c index ad15b5ef2599..c07327487111 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -572,6 +572,8 @@ static int move_to_new_page(struct page *newpage, struct page *page) /* Prepare mapping for the new page.*/ newpage->index = page->index; newpage->mapping = page->mapping; + if (PageSwapBacked(page)) + SetPageSwapBacked(newpage); mapping = page_mapping(page); if (!mapping) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index ee7a96ef40dc..2099904d6cc4 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -462,6 +462,8 @@ static inline int free_pages_check(struct page *page) bad_page(page); if (PageDirty(page)) __ClearPageDirty(page); + if (PageSwapBacked(page)) + __ClearPageSwapBacked(page); /* * For now, we report if PG_reserved was found set, but do not * clear it, and do not free the page. But we shall soon need diff --git a/mm/shmem.c b/mm/shmem.c index d87958a5f03e..fd421ed703ed 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1367,6 +1367,7 @@ static int shmem_getpage(struct inode *inode, unsigned long idx, error = -ENOMEM; goto failed; } + SetPageSwapBacked(filepage); /* Precharge page while we can wait, compensate after */ error = mem_cgroup_cache_charge(filepage, current->mm, diff --git a/mm/swap_state.c b/mm/swap_state.c index 797c3831cbec..7a3ece0b5a3b 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -75,6 +75,7 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask) BUG_ON(!PageLocked(page)); BUG_ON(PageSwapCache(page)); BUG_ON(PagePrivate(page)); + BUG_ON(!PageSwapBacked(page)); error = radix_tree_preload(gfp_mask); if (!error) { page_cache_get(page); @@ -303,6 +304,7 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, * May fail (-ENOMEM) if radix-tree node allocation failed. */ set_page_locked(new_page); + SetPageSwapBacked(new_page); err = add_to_swap_cache(new_page, entry, gfp_mask & GFP_KERNEL); if (likely(!err)) { /* @@ -312,6 +314,7 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, swap_readpage(NULL, new_page); return new_page; } + ClearPageSwapBacked(new_page); clear_page_locked(new_page); swap_free(entry); } while (err != -ENOMEM);