The patch titled Subject: mm: add folio_flush_mapping() has been added to the -mm mm-unstable branch. Its filename is mm-add-folio_flush_mapping.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-add-folio_flush_mapping.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: mm: add folio_flush_mapping() Date: Mon, 10 Jul 2023 21:43:05 +0100 This is the folio equivalent of page_mapping_file(), but rename it to make it clear that it's very different from page_file_mapping(). Theoretically, there's nothing flush-only about it, but there are no other users today, and I doubt there will be; it's almost always more useful to know the swapfile's mapping or the swapcache's mapping. Link: https://lkml.kernel.org/r/20230710204339.3554919-5-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx> Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/pagemap.h | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) --- a/include/linux/pagemap.h~mm-add-folio_flush_mapping +++ a/include/linux/pagemap.h @@ -389,6 +389,26 @@ static inline struct address_space *foli return folio->mapping; } +/** + * folio_flush_mapping - Find the file mapping this folio belongs to. + * @folio: The folio. + * + * For folios which are in the page cache, return the mapping that this + * page belongs to. Anonymous folios return NULL, even if they're in + * the swap cache. Other kinds of folio also return NULL. + * + * This is ONLY used by architecture cache flushing code. If you aren't + * writing cache flushing code, you want either folio_mapping() or + * folio_file_mapping(). + */ +static inline struct address_space *folio_flush_mapping(struct folio *folio) +{ + if (unlikely(folio_test_swapcache(folio))) + return NULL; + + return folio_mapping(folio); +} + static inline struct address_space *page_file_mapping(struct page *page) { return folio_file_mapping(page_folio(page)); @@ -399,11 +419,7 @@ static inline struct address_space *page */ static inline struct address_space *page_mapping_file(struct page *page) { - struct folio *folio = page_folio(page); - - if (unlikely(folio_test_swapcache(folio))) - return NULL; - return folio_mapping(folio); + return folio_flush_mapping(page_folio(page)); } /** _ Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are rmap-pass-the-folio-to-__page_check_anon_rmap.patch minmax-add-in_range-macro.patch mm-convert-page_table_check_pte_set-to-page_table_check_ptes_set.patch mm-add-generic-flush_icache_pages-and-documentation.patch mm-add-folio_flush_mapping.patch mm-remove-arch_implements_flush_dcache_folio.patch mm-add-default-definition-of-set_ptes.patch alpha-implement-the-new-page-table-range-api.patch arc-implement-the-new-page-table-range-api.patch arm-implement-the-new-page-table-range-api.patch arm64-implement-the-new-page-table-range-api.patch csky-implement-the-new-page-table-range-api.patch hexagon-implement-the-new-page-table-range-api.patch ia64-implement-the-new-page-table-range-api.patch loongarch-implement-the-new-page-table-range-api.patch m68k-implement-the-new-page-table-range-api.patch microblaze-implement-the-new-page-table-range-api.patch mips-implement-the-new-page-table-range-api.patch nios2-implement-the-new-page-table-range-api.patch openrisc-implement-the-new-page-table-range-api.patch parisc-implement-the-new-page-table-range-api.patch powerpc-implement-the-new-page-table-range-api.patch riscv-implement-the-new-page-table-range-api.patch s390-implement-the-new-page-table-range-api.patch sh-implement-the-new-page-table-range-api.patch sparc32-implement-the-new-page-table-range-api.patch sparc64-implement-the-new-page-table-range-api.patch um-implement-the-new-page-table-range-api.patch x86-implement-the-new-page-table-range-api.patch xtensa-implement-the-new-page-table-range-api.patch mm-remove-page_mapping_file.patch mm-rationalise-flush_icache_pages-and-flush_icache_page.patch mm-tidy-up-set_ptes-definition.patch mm-use-flush_icache_pages-in-do_set_pmd.patch mm-call-update_mmu_cache_range-in-more-page-fault-handling-paths.patch