[PATCH v3 3/3] mm: Wait for writeback when grabbing pages to begin a write
From: Darrick J. Wong <hidden>
Date: 2011-05-04 17:42:27
Also in:
linux-fsdevel, linux-mm, linux-scsi, lkml
Subsystem:
memory management, page cache, the rest · Maintainers:
Andrew Morton, Matthew Wilcox, Linus Torvalds
When grabbing a page for a buffered IO write, the mm should wait for writeback on the page to complete so that the page does not become writable during the IO operation. Signed-off-by: Darrick J. Wong <redacted> --- mm/filemap.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/mm/filemap.c b/mm/filemap.c
index c641edf..c22675f 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c@@ -2287,8 +2287,10 @@ struct page *grab_cache_page_write_begin(struct address_space *mapping, gfp_notmask = __GFP_FS; repeat: page = find_lock_page(mapping, index); - if (page) + if (page) { + wait_on_page_writeback(page); return page; + } page = __page_cache_alloc(mapping_gfp_mask(mapping) & ~gfp_notmask); if (!page)
@@ -2301,6 +2303,7 @@ repeat: goto repeat; return NULL; } + wait_on_page_writeback(page); return page; } EXPORT_SYMBOL(grab_cache_page_write_begin);