diff options
author | Mike Snitzer <snitzer@redhat.com> | 2014-07-14 16:35:54 -0400 |
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committer | Mike Snitzer <snitzer@redhat.com> | 2014-07-15 14:05:26 -0400 |
commit | 9aec8629ec829fc9403788cd959e05dd87988bd1 (patch) | |
tree | 16ef5465ee0b354f266fcdec89240f64212ef622 | |
parent | 7a7a3b45fed9a144dbf766ee842a4c5d0632b81d (diff) | |
download | linux-9aec8629ec829fc9403788cd959e05dd87988bd1.tar.bz2 |
dm thin metadata: do not allow the data block size to change
The block size for the thin-pool's data device must remained fixed for
the life of the thin-pool. Disallow any attempt to change the
thin-pool's data block size.
It should be noted that attempting to change the data block size via
thin-pool table reload will be ignored as a side-effect of the thin-pool
handover that the thin-pool target does during thin-pool table reload.
Here is an example outcome of attempting to load a thin-pool table that
reduced the thin-pool's data block size from 1024K to 512K.
Before:
kernel: device-mapper: thin: 253:4: growing the data device from 204800 to 409600 blocks
After:
kernel: device-mapper: thin metadata: changing the data block size (from 2048 to 1024) is not supported
kernel: device-mapper: table: 253:4: thin-pool: Error creating metadata object
kernel: device-mapper: ioctl: error adding target to table
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Cc: stable@vger.kernel.org
-rw-r--r-- | drivers/md/dm-thin-metadata.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c index b086a945edcb..e9d33ad59df5 100644 --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -613,6 +613,15 @@ static int __open_metadata(struct dm_pool_metadata *pmd) disk_super = dm_block_data(sblock); + /* Verify the data block size hasn't changed */ + if (le32_to_cpu(disk_super->data_block_size) != pmd->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)pmd->data_block_size); + r = -EINVAL; + goto bad_unlock_sblock; + } + r = __check_incompat_features(disk_super, pmd); if (r < 0) goto bad_unlock_sblock; |