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. This change is needed to provide page stability during writes for all filesystems. Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx> --- mm/filemap.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index c641edf..fd0e7f2 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2288,7 +2288,7 @@ struct page *grab_cache_page_write_begin(struct address_space *mapping, repeat: page = find_lock_page(mapping, index); if (page) - return page; + goto found; page = __page_cache_alloc(mapping_gfp_mask(mapping) & ~gfp_notmask); if (!page) @@ -2301,6 +2301,8 @@ repeat: goto repeat; return NULL; } +found: + wait_on_page_writeback(page); return page; } EXPORT_SYMBOL(grab_cache_page_write_begin); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>