From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756662AbaHHUly (ORCPT ); Fri, 8 Aug 2014 16:41:54 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:40148 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756495AbaHHUlt (ORCPT ); Fri, 8 Aug 2014 16:41:49 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Mike Snitzer , Kamal Mostafa Subject: [PATCH 3.13 140/259] dm thin metadata: do not allow the data block size to change Date: Fri, 8 Aug 2014 13:39:23 -0700 Message-Id: <1407530482-4483-141-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1407530482-4483-1-git-send-email-kamal@canonical.com> References: <1407530482-4483-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13.11.6 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Mike Snitzer commit 9aec8629ec829fc9403788cd959e05dd87988bd1 upstream. 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 Acked-by: Joe Thornber Signed-off-by: Kamal Mostafa --- drivers/md/dm-thin-metadata.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c index 07a6ea3..b63095c 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; -- 1.9.1