ocfs2: Fix deadlock when allocating page

We cannot call grab_cache_page() when holding filesystem locks or with
a transaction started as grab_cache_page() calls page allocation with
GFP_KERNEL flag and thus page reclaim can recurse back into the filesystem
causing deadlocks or various assertion failures. We have to use
find_or_create_page() instead and pass it GFP_NOFS as we do with other
allocations.

Acked-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Tao Ma <tao.ma@oracle.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 6b2be0f2eacd..2caa3a7a1a39 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -783,7 +783,7 @@ static int ocfs2_write_zero_page(struct inode *inode, u64 abs_from,
         BUG_ON(abs_to > (((u64)index + 1) << PAGE_CACHE_SHIFT));
         BUG_ON(abs_from & (inode->i_blkbits - 1));
 
-        page = grab_cache_page(mapping, index);
+        page = find_or_create_page(mapping, index, GFP_NOFS);
         if (!page) {
                 ret = -ENOMEM;
                 mlog_errno(ret);