The patch titled Subject: mm: methods for teaching filesystems about PG_swapcache pages has been removed from the -mm tree. Its filename was mm-methods-for-teaching-filesystems-about-pg_swapcache-pages.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Mel Gorman <mgorman@xxxxxxx> Subject: mm: methods for teaching filesystems about PG_swapcache pages In order to teach filesystems to handle swap cache pages, three new page functions are introduced: pgoff_t page_file_index(struct page *); loff_t page_file_offset(struct page *); struct address_space *page_file_mapping(struct page *); page_file_index() - gives the offset of this page in the file in PAGE_CACHE_SIZE blocks. Like page->index is for mapped pages, this function also gives the correct index for PG_swapcache pages. page_file_offset() - uses page_file_index(), so that it will give the expected result, even for PG_swapcache pages. page_file_mapping() - gives the mapping backing the actual page; that is for swap cache pages it will give swap_file->f_mapping. Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Signed-off-by: Mel Gorman <mgorman@xxxxxxx> Reviewed-by: Rik van Riel <riel@xxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: David S. Miller <davem@xxxxxxxxxxxxx> Cc: Eric B Munson <emunson@xxxxxxxxx> Cc: Eric Paris <eparis@xxxxxxxxxx> Cc: James Morris <jmorris@xxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Mike Christie <michaelc@xxxxxxxxxxx> Cc: Neil Brown <neilb@xxxxxxx> Cc: Sebastian Andrzej Siewior <sebastian@xxxxxxxxxxxxx> Cc: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> Cc: Xiaotian Feng <dfeng@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/mm.h | 25 +++++++++++++++++++++++++ include/linux/pagemap.h | 5 +++++ include/linux/swap.h | 1 + mm/swapfile.c | 26 ++++++++++++++++++++++++++ 4 files changed, 57 insertions(+) diff -puN include/linux/mm.h~mm-methods-for-teaching-filesystems-about-pg_swapcache-pages include/linux/mm.h --- a/include/linux/mm.h~mm-methods-for-teaching-filesystems-about-pg_swapcache-pages +++ a/include/linux/mm.h @@ -805,6 +805,17 @@ static inline void *page_rmapping(struct return (void *)((unsigned long)page->mapping & ~PAGE_MAPPING_FLAGS); } +extern struct address_space *__page_file_mapping(struct page *); + +static inline +struct address_space *page_file_mapping(struct page *page) +{ + if (unlikely(PageSwapCache(page))) + return __page_file_mapping(page); + + return page->mapping; +} + static inline int PageAnon(struct page *page) { return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0; @@ -821,6 +832,20 @@ static inline pgoff_t page_index(struct return page->index; } +extern pgoff_t __page_file_index(struct page *page); + +/* + * Return the file index of the page. Regular pagecache pages use ->index + * whereas swapcache pages use swp_offset(->private) + */ +static inline pgoff_t page_file_index(struct page *page) +{ + if (unlikely(PageSwapCache(page))) + return __page_file_index(page); + + return page->index; +} + /* * Return true if this page is mapped into pagetables. */ diff -puN include/linux/pagemap.h~mm-methods-for-teaching-filesystems-about-pg_swapcache-pages include/linux/pagemap.h --- a/include/linux/pagemap.h~mm-methods-for-teaching-filesystems-about-pg_swapcache-pages +++ a/include/linux/pagemap.h @@ -286,6 +286,11 @@ static inline loff_t page_offset(struct return ((loff_t)page->index) << PAGE_CACHE_SHIFT; } +static inline loff_t page_file_offset(struct page *page) +{ + return ((loff_t)page_file_index(page)) << PAGE_CACHE_SHIFT; +} + extern pgoff_t linear_hugepage_index(struct vm_area_struct *vma, unsigned long address); diff -puN include/linux/swap.h~mm-methods-for-teaching-filesystems-about-pg_swapcache-pages include/linux/swap.h --- a/include/linux/swap.h~mm-methods-for-teaching-filesystems-about-pg_swapcache-pages +++ a/include/linux/swap.h @@ -356,6 +356,7 @@ extern unsigned int count_swap_pages(int extern sector_t map_swap_page(struct page *, struct block_device **); extern sector_t swapdev_block(int, pgoff_t); extern int page_swapcount(struct page *); +extern struct swap_info_struct *page_swap_info(struct page *); extern int reuse_swap_page(struct page *); extern int try_to_free_swap(struct page *); struct backing_dev_info; diff -puN mm/swapfile.c~mm-methods-for-teaching-filesystems-about-pg_swapcache-pages mm/swapfile.c --- a/mm/swapfile.c~mm-methods-for-teaching-filesystems-about-pg_swapcache-pages +++ a/mm/swapfile.c @@ -33,6 +33,7 @@ #include <linux/oom.h> #include <linux/frontswap.h> #include <linux/swapfile.h> +#include <linux/export.h> #include <asm/pgtable.h> #include <asm/tlbflush.h> @@ -2285,6 +2286,31 @@ int swapcache_prepare(swp_entry_t entry) return __swap_duplicate(entry, SWAP_HAS_CACHE); } +struct swap_info_struct *page_swap_info(struct page *page) +{ + swp_entry_t swap = { .val = page_private(page) }; + BUG_ON(!PageSwapCache(page)); + return swap_info[swp_type(swap)]; +} + +/* + * out-of-line __page_file_ methods to avoid include hell. + */ +struct address_space *__page_file_mapping(struct page *page) +{ + VM_BUG_ON(!PageSwapCache(page)); + return page_swap_info(page)->swap_file->f_mapping; +} +EXPORT_SYMBOL_GPL(__page_file_mapping); + +pgoff_t __page_file_index(struct page *page) +{ + swp_entry_t swap = { .val = page_private(page) }; + VM_BUG_ON(!PageSwapCache(page)); + return swp_offset(swap); +} +EXPORT_SYMBOL_GPL(__page_file_index); + /* * add_swap_count_continuation - called when a swap count is duplicated * beyond SWAP_MAP_MAX, it allocates a new page and links that to the entry's _ Patches currently in -mm which might be from mgorman@xxxxxxx are origin.patch linux-next.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html