dm cache metadata: do not allow the data block size to change

The block size for the dm-cache's data device must remained fixed for
the life of the cache.  Disallow any attempt to change the cache's data
block size.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Cc: stable@vger.kernel.org
This commit is contained in:
Mike Snitzer 2014-07-14 16:59:39 -04:00
parent 9aec8629ec
commit 048e5a07f2

View File

@ -425,6 +425,15 @@ static int __open_metadata(struct dm_cache_metadata *cmd)
disk_super = dm_block_data(sblock);
/* Verify the data block size hasn't changed */
if (le32_to_cpu(disk_super->data_block_size) != cmd->data_block_size) {
DMERR("changing the data block size (from %u to %llu) is not supported",
le32_to_cpu(disk_super->data_block_size),
(unsigned long long)cmd->data_block_size);
r = -EINVAL;
goto bad;
}
r = __check_incompat_features(disk_super, cmd);
if (r < 0)
goto bad;