From b27652d935f41793c5e229a1e8b3a8bb3afe3cc1 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Thu, 24 Dec 2020 12:55:56 -0500 Subject: mm/filemap: Add FGP_STABLE Allow filemap_get_folio() to wait for writeback to complete (if the filesystem wants that behaviour). This is the folio equivalent of grab_cache_page_write_begin(), which is moved into the folio-compat file as a reminder to migrate all the code using it. This paves the way for getting rid of AOP_FLAG_NOFS once grab_cache_page_write_begin() is removed. Kernel grows by 11 bytes. filemap_get_folio() grows by 33 bytes but grab_cache_page_write_begin() shrinks by 22 bytes to make up for it. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: David Howells Acked-by: Vlastimil Babka --- mm/folio-compat.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'mm/folio-compat.c') diff --git a/mm/folio-compat.c b/mm/folio-compat.c index e833e680e944..5b6ae1da314e 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -116,6 +116,7 @@ int add_to_page_cache_lru(struct page *page, struct address_space *mapping, } EXPORT_SYMBOL(add_to_page_cache_lru); +noinline struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, int fgp_flags, gfp_t gfp) { @@ -127,3 +128,15 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, return folio_file_page(folio, index); } EXPORT_SYMBOL(pagecache_get_page); + +struct page *grab_cache_page_write_begin(struct address_space *mapping, + pgoff_t index, unsigned flags) +{ + unsigned fgp_flags = FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE; + + if (flags & AOP_FLAG_NOFS) + fgp_flags |= FGP_NOFS; + return pagecache_get_page(mapping, index, fgp_flags, + mapping_gfp_mask(mapping)); +} +EXPORT_SYMBOL(grab_cache_page_write_begin); -- cgit v1.2.3-58-ga151