diff options
| author | Yongqiang Yang <xiaoqiangnk@gmail.com> | 2011-12-13 21:51:55 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-12-21 12:58:34 -0800 |
| commit | 8afe1f656c3cb0eff4219e3a4a22b95579148ad6 (patch) | |
| tree | bb5b6bb6462a21ee858a9af7d7bd4551979223c0 | |
| parent | d118bc3aec8134c35f9de6dbb85d6c30d71a1b54 (diff) | |
ext4: avoid potential hang in mpage_submit_io() when blocksize < pagesize
commit 13a79a4741d37fda2fbafb953f0f301dc007928f upstream.
If there is an unwritten but clean buffer in a page and there is a
dirty buffer after the buffer, then mpage_submit_io does not write the
dirty buffer out. As a result, da_writepages loops forever.
This patch fixes the problem by checking dirty flag.
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | fs/ext4/inode.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index d33c7375bfda..5dbdb6b91ae7 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1261,8 +1261,11 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd, clear_buffer_unwritten(bh); } - /* skip page if block allocation undone */ - if (buffer_delay(bh) || buffer_unwritten(bh)) + /* + * skip page if block allocation undone and + * block is dirty + */ + if (ext4_bh_delay_or_unwritten(NULL, bh)) skip_page = 1; bh = bh->b_this_page; block_start += bh->b_size; |