diff options
| -rw-r--r-- | Documentation/core-api/mm-api.rst | 2 | ||||
| -rw-r--r-- | include/linux/mm.h | 14 | ||||
| -rw-r--r-- | include/linux/pagemap.h | 35 | ||||
| -rw-r--r-- | include/linux/swap.h | 6 | ||||
| -rw-r--r-- | mm/Makefile | 2 | ||||
| -rw-r--r-- | mm/folio-compat.c | 13 | ||||
| -rw-r--r-- | mm/swapfile.c | 8 | ||||
| -rw-r--r-- | mm/util.c | 30 |
8 files changed, 77 insertions, 33 deletions
diff --git a/Documentation/core-api/mm-api.rst b/Documentation/core-api/mm-api.rst index 971149f5d241..395835f9289f 100644 --- a/Documentation/core-api/mm-api.rst +++ b/Documentation/core-api/mm-api.rst @@ -101,3 +101,5 @@ More Memory Management Functions :internal: .. kernel-doc:: include/linux/page_ref.h .. kernel-doc:: include/linux/mmzone.h +.. kernel-doc:: mm/util.c + :functions: folio_mapping diff --git a/include/linux/mm.h b/include/linux/mm.h index 63685d953ce0..bc5c38e1f780 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1755,19 +1755,6 @@ void page_address_init(void); extern void *page_rmapping(struct page *page); extern struct anon_vma *page_anon_vma(struct page *page); -extern struct address_space *page_mapping(struct page *page); - -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; -} - extern pgoff_t __page_file_index(struct page *page); /* @@ -1782,7 +1769,6 @@ static inline pgoff_t page_index(struct page *page) } bool page_mapped(struct page *page); -struct address_space *page_mapping(struct page *page); /* * Return true only if the page has been allocated with diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 3354117a1dae..0ca96a40fabe 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -162,14 +162,45 @@ static inline void filemap_nr_thps_dec(struct address_space *mapping) void release_pages(struct page **pages, int nr); +struct address_space *page_mapping(struct page *); +struct address_space *folio_mapping(struct folio *); +struct address_space *swapcache_mapping(struct folio *); + +/** + * folio_file_mapping - Find the mapping this folio belongs to. + * @folio: The folio. + * + * For folios which are in the page cache, return the mapping that this + * page belongs to. Folios in the swap cache return the mapping of the + * swap file or swap device where the data is stored. This is different + * from the mapping returned by folio_mapping(). The only reason to + * use it is if, like NFS, you return 0 from ->activate_swapfile. + * + * Do not call this for folios which aren't in the page cache or swap cache. + */ +static inline struct address_space *folio_file_mapping(struct folio *folio) +{ + if (unlikely(folio_test_swapcache(folio))) + return swapcache_mapping(folio); + + return folio->mapping; +} + +static inline struct address_space *page_file_mapping(struct page *page) +{ + return folio_file_mapping(page_folio(page)); +} + /* * For file cache pages, return the address_space, otherwise return NULL */ static inline struct address_space *page_mapping_file(struct page *page) { - if (unlikely(PageSwapCache(page))) + struct folio *folio = page_folio(page); + + if (unlikely(folio_test_swapcache(folio))) return NULL; - return page_mapping(page); + return folio_mapping(folio); } static inline bool page_cache_add_speculative(struct page *page, int count) diff --git a/include/linux/swap.h b/include/linux/swap.h index ba52f3a3478e..85607c6c0cba 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -320,6 +320,12 @@ struct vma_swap_readahead { #endif }; +static inline swp_entry_t folio_swap_entry(struct folio *folio) +{ + swp_entry_t entry = { .val = page_private(&folio->page) }; + return entry; +} + /* linux/mm/workingset.c */ void workingset_age_nonresident(struct lruvec *lruvec, unsigned long nr_pages); void *workingset_eviction(struct page *page, struct mem_cgroup *target_memcg); diff --git a/mm/Makefile b/mm/Makefile index fc60a40ce954..d6c0042e3aa0 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -46,7 +46,7 @@ mmu-$(CONFIG_MMU) += process_vm_access.o endif obj-y := filemap.o mempool.o oom_kill.o fadvise.o \ - maccess.o page-writeback.o \ + maccess.o page-writeback.o folio-compat.o \ readahead.o swap.o truncate.o vmscan.o shmem.o \ util.o mmzone.o vmstat.o backing-dev.o \ mm_init.o percpu.o slab_common.o \ diff --git a/mm/folio-compat.c b/mm/folio-compat.c new file mode 100644 index 000000000000..5e107aa30a62 --- /dev/null +++ b/mm/folio-compat.c @@ -0,0 +1,13 @@ +/* + * Compatibility functions which bloat the callers too much to make inline. + * All of the callers of these functions should be converted to use folios + * eventually. + */ + +#include <linux/pagemap.h> + +struct address_space *page_mapping(struct page *page) +{ + return folio_mapping(page_folio(page)); +} +EXPORT_SYMBOL(page_mapping); diff --git a/mm/swapfile.c b/mm/swapfile.c index 22d10f713848..e3dcaeecc50f 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3534,13 +3534,13 @@ struct swap_info_struct *page_swap_info(struct page *page) } /* - * out-of-line __page_file_ methods to avoid include hell. + * out-of-line methods to avoid include hell. */ -struct address_space *__page_file_mapping(struct page *page) +struct address_space *swapcache_mapping(struct folio *folio) { - return page_swap_info(page)->swap_file->f_mapping; + return page_swap_info(&folio->page)->swap_file->f_mapping; } -EXPORT_SYMBOL_GPL(__page_file_mapping); +EXPORT_SYMBOL_GPL(swapcache_mapping); pgoff_t __page_file_index(struct page *page) { diff --git a/mm/util.c b/mm/util.c index bacabe446906..6c1fe9bee30a 100644 --- a/mm/util.c +++ b/mm/util.c @@ -705,30 +705,36 @@ struct anon_vma *page_anon_vma(struct page *page) return __page_rmapping(page); } -struct address_space *page_mapping(struct page *page) +/** + * folio_mapping - Find the mapping where this folio is stored. + * @folio: The folio. + * + * For folios which are in the page cache, return the mapping that this + * page belongs to. Folios in the swap cache return the swap mapping + * this page is stored in (which is different from the mapping for the + * swap file or swap device where the data is stored). + * + * You can call this for folios which aren't in the swap cache or page + * cache and it will return NULL. + */ +struct address_space *folio_mapping(struct folio *folio) { struct address_space *mapping; - page = compound_head(page); - /* This happens if someone calls flush_dcache_page on slab page */ - if (unlikely(PageSlab(page))) + if (unlikely(folio_test_slab(folio))) return NULL; - if (unlikely(PageSwapCache(page))) { - swp_entry_t entry; - - entry.val = page_private(page); - return swap_address_space(entry); - } + if (unlikely(folio_test_swapcache(folio))) + return swap_address_space(folio_swap_entry(folio)); - mapping = page->mapping; + mapping = folio->mapping; if ((unsigned long)mapping & PAGE_MAPPING_ANON) return NULL; return (void *)((unsigned long)mapping & ~PAGE_MAPPING_FLAGS); } -EXPORT_SYMBOL(page_mapping); +EXPORT_SYMBOL(folio_mapping); /* Slow path of page_mapcount() for compound pages */ int __page_mapcount(struct page *page) |