From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Darrick J. Wong" Subject: [PATCH 4/9] mke2fs: store checksum seed at format time Date: Sat, 13 Feb 2016 14:37:51 -0800 Message-ID: <20160213223751.25381.93488.stgit@birch.djwong.org> References: <20160213223725.25381.20929.stgit@birch.djwong.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: linux-ext4@vger.kernel.org To: tytso@mit.edu, darrick.wong@oracle.com Return-path: Received: from aserp1040.oracle.com ([141.146.126.69]:33952 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751064AbcBMWhy (ORCPT ); Sat, 13 Feb 2016 17:37:54 -0500 In-Reply-To: <20160213223725.25381.20929.stgit@birch.djwong.org> Sender: linux-ext4-owner@vger.kernel.org List-ID: Allow users to turn on metadata_csum_seed at format time so that UUIDs can be live-changed at any time. Signed-off-by: Darrick J. Wong --- misc/mke2fs.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/misc/mke2fs.c b/misc/mke2fs.c index dd467f2..7d31e42 100644 --- a/misc/mke2fs.c +++ b/misc/mke2fs.c @@ -1074,7 +1074,8 @@ static __u32 ok_features[3] = { EXT4_FEATURE_INCOMPAT_MMP | EXT4_FEATURE_INCOMPAT_64BIT| EXT4_FEATURE_INCOMPAT_INLINE_DATA| - EXT4_FEATURE_INCOMPAT_ENCRYPT, + EXT4_FEATURE_INCOMPAT_ENCRYPT | + EXT4_FEATURE_INCOMPAT_CSUM_SEED, /* R/O compat */ EXT2_FEATURE_RO_COMPAT_LARGE_FILE| EXT4_FEATURE_RO_COMPAT_HUGE_FILE| @@ -2774,6 +2775,13 @@ int main (int argc, char *argv[]) "Pass -O 64bit to rectify.\n")); } + if (ext2fs_has_feature_csum_seed(fs->super) && + !ext2fs_has_feature_metadata_csum(fs->super)) { + printf("%s", _("The metadata_csum_seed feature " + "requres the metadata_csum feature.\n")); + exit(1); + } + /* Calculate journal blocks */ if (!journal_device && ((journal_size) || ext2fs_has_feature_journal(&fs_param))) @@ -2829,6 +2837,11 @@ int main (int argc, char *argv[]) } } else uuid_generate(fs->super->s_uuid); + + if (ext2fs_has_feature_csum_seed(fs->super)) + fs->super->s_checksum_seed = ext2fs_crc32c_le(~0, + fs->super->s_uuid, sizeof(fs->super->s_uuid)); + ext2fs_init_csum_seed(fs); /*