diff options
| author | Joe Thornber <ejt@redhat.com> | 2015-02-27 15:09:12 +0100 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2015-02-27 15:59:12 +0100 |
| commit | 5f027a3bf184d1d36e68745f7cd3718a8b879cc0 (patch) | |
| tree | e20a70437603a46f5dbf98474ba03ada49ea9e4a /drivers/md | |
| parent | Linux 4.0-rc1 (diff) | |
| download | linux-5f027a3bf184d1d36e68745f7cd3718a8b879cc0.tar.xz linux-5f027a3bf184d1d36e68745f7cd3718a8b879cc0.zip | |
dm thin: fix to consistently zero-fill reads to unprovisioned blocks
It was always intended that a read to an unprovisioned block will return
zeroes regardless of whether the pool is in read-only or read-write
mode. thin_bio_map() was inconsistent with its handling of such reads
when the pool is in read-only mode, it now properly zero-fills the bios
it returns in response to unprovisioned block reads.
Eliminate thin_bio_map()'s special read-only mode handling of -ENODATA
and just allow the IO to be deferred to the worker which will result in
pool->process_bio() handling the IO (which already properly zero-fills
reads to unprovisioned blocks).
Reported-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-thin.c | 11 |
1 files changed, 0 insertions, 11 deletions
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index 654773cb1eee..921aafd12aee 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -2358,17 +2358,6 @@ static int thin_bio_map(struct dm_target *ti, struct bio *bio) return DM_MAPIO_REMAPPED; case -ENODATA: - if (get_pool_mode(tc->pool) == PM_READ_ONLY) { - /* - * This block isn't provisioned, and we have no way - * of doing so. - */ - handle_unserviceable_bio(tc->pool, bio); - cell_defer_no_holder(tc, virt_cell); - return DM_MAPIO_SUBMITTED; - } - /* fall through */ - case -EWOULDBLOCK: thin_defer_cell(tc, virt_cell); return DM_MAPIO_SUBMITTED; |