diff options
| author | Christoph Hellwig <hch@lst.de> | 2017-02-06 22:00:54 +0100 |
|---|---|---|
| committer | Darrick J. Wong <darrick.wong@oracle.com> | 2017-02-07 02:47:46 +0100 |
| commit | 54a4ef8af4e0dc5c983d17fcb9cf5fd25666d94e (patch) | |
| tree | 47f55c2f61169e2774cd73770c2237ff9356a5ec /.get_maintainer.ignore | |
| parent | xfs: reset b_first_retry_time when clear the retry status of xfs_buf_t (diff) | |
| download | linux-54a4ef8af4e0dc5c983d17fcb9cf5fd25666d94e.tar.xz linux-54a4ef8af4e0dc5c983d17fcb9cf5fd25666d94e.zip | |
xfs: reject all unaligned direct writes to reflinked files
We currently fall back from direct to buffered writes if we detect a
remaining shared extent in the iomap_begin callback. But by the time
iomap_begin is called for the potentially unaligned end block we might
have already written most of the data to disk, which we'd now write
again using buffered I/O. To avoid this reject all writes to reflinked
files before starting I/O so that we are guaranteed to only write the
data once.
The alternative would be to unshare the unaligned start and/or end block
before doing the I/O. I think that's doable, and will actually be
required to support reflinks on DAX file system. But it will take a
little more time and I'd rather get rid of the double write ASAP.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Diffstat (limited to '.get_maintainer.ignore')
0 files changed, 0 insertions, 0 deletions