diff options
| author | Josef Bacik <jbacik@fusionio.com> | 2013-07-02 10:38:02 -0400 |
|---|---|---|
| committer | Josef Bacik <jbacik@fusionio.com> | 2013-07-02 11:51:49 -0400 |
| commit | 0e267c44c3a402d35111d1935be1167240b5b79f (patch) | |
| tree | d09bc2390133da4ca34a4d11ca34ef524d03a87d | |
| parent | 7fb7d76f96bfcbea25007d190ba828b18e13d29d (diff) | |
Btrfs: wait ordered range before doing direct io
My recent truncate patch uncovered this bug, but I can reproduce it without the
truncate patch. If you mount with -o compress-force, do a direct write to some
area, do a buffered write to some other area, and then do a direct read you will
get the wrong data for where you did the buffered write. This is because the
generic direct io helpers only call filemap_write_and_wait once, and for
compression we need it twice. So to be safe add the btrfs_wait_ordered_range to
the start of the direct io function to make sure any compressed writes have
truly been written. This patch makes xfstests 130 pass when you mount with -o
compress-force=lzo. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
| -rw-r--r-- | fs/btrfs/inode.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 0a43d42268f7..55dda871437f 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c | |||
| @@ -7270,8 +7270,16 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, | |||
| 7270 | atomic_inc(&inode->i_dio_count); | 7270 | atomic_inc(&inode->i_dio_count); |
| 7271 | smp_mb__after_atomic_inc(); | 7271 | smp_mb__after_atomic_inc(); |
| 7272 | 7272 | ||
| 7273 | /* | ||
| 7274 | * The generic stuff only does filemap_write_and_wait_range, which isn't | ||
| 7275 | * enough if we've written compressed pages to this area, so we need to | ||
| 7276 | * call btrfs_wait_ordered_range to make absolutely sure that any | ||
| 7277 | * outstanding dirty pages are on disk. | ||
| 7278 | */ | ||
| 7279 | count = iov_length(iov, nr_segs); | ||
| 7280 | btrfs_wait_ordered_range(inode, offset, count); | ||
| 7281 | |||
| 7273 | if (rw & WRITE) { | 7282 | if (rw & WRITE) { |
| 7274 | count = iov_length(iov, nr_segs); | ||
| 7275 | /* | 7283 | /* |
| 7276 | * If the write DIO is beyond the EOF, we need update | 7284 | * If the write DIO is beyond the EOF, we need update |
| 7277 | * the isize, but it is protected by i_mutex. So we can | 7285 | * the isize, but it is protected by i_mutex. So we can |