[PATCH 5/6] ocfs2: Wait for page writeback to provide stable pages

When stable pages are required, we have to wait if the page is just
going to disk and we want to modify it. Add proper callback to
ocfs2_grab_pages_for_write().

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <jlbec@evilplan.org>
CC: Mark Fasheh <redacted>
From: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Darrick J. Wong <redacted>
---
 fs/ocfs2/aops.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 6577432..9796330 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c

@@ -1194,6 +1194,7 @@ static int ocfs2_grab_pages_for_write(struct address_space *mapping,
 				goto out;
 			}
 		}
+		wait_for_stable_page(wc->w_pages[i]);
 
 		if (index == target_index)
 			wc->w_target_page = wc->w_pages[i];