diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2011-08-13 12:58:21 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-08-29 13:29:11 -0700 |
| commit | 45df4b8977852ea12d6ed19f6c87e6765f6c31e5 (patch) | |
| tree | 50111bd57a1849b89b0b0578c31788077bda6452 /fs | |
| parent | 4eddd2a50f2548c6c83081fde8fdbc3de07626f6 (diff) | |
ext4: fix nomblk_io_submit option so it correctly converts uninit blocks
commit 9dd75f1f1a02d656a11a7b9b9e6c2759b9c1e946 upstream.
Bug discovered by Jan Kara:
Finally, commit 1449032be17abb69116dbc393f67ceb8bd034f92 returned back
the old IO submission code but apparently it forgot to return the old
handling of uninitialized buffers so we unconditionnaly call
block_write_full_page() without specifying end_io function. So AFAICS
we never convert unwritten extents to written in some cases. For
example when I mount the fs as: mount -t ext4 -o
nomblk_io_submit,dioread_nolock /dev/ubdb /mnt and do
int fd = open(argv[1], O_RDWR | O_CREAT | O_TRUNC, 0600);
char buf[1024];
memset(buf, 'a', sizeof(buf));
fallocate(fd, 0, 0, 16384);
write(fd, buf, sizeof(buf));
I get a file full of zeros (after remounting the filesystem so that
pagecache is dropped) instead of seeing the first KB contain 'a's.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/inode.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 5390b4da0dd..b864839e1d6 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2156,7 +2156,12 @@ static int mpage_da_submit_io(struct mpage_da_data *mpd, else if (test_opt(inode->i_sb, MBLK_IO_SUBMIT)) err = ext4_bio_write_page(&io_submit, page, len, mpd->wbc); - else + else if (buffer_uninit(page_bufs)) { + ext4_set_bh_endio(page_bufs, inode); + err = block_write_full_page_endio(page, + noalloc_get_block_write, + mpd->wbc, ext4_end_io_buffer_write); + } else err = block_write_full_page(page, noalloc_get_block_write, mpd->wbc); |