From: "Darrick J. Wong" Subject: [PATCH 42/51] libext2fs: Change on-disk journal layout to support metadata checksumming Date: Sat, 07 Jan 2012 00:37:25 -0800 Message-ID: <20120107083725.25788.90779.stgit@elm3c44.beaverton.ibm.com> References: <20120107083256.25788.41238.stgit@elm3c44.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Sunil Mushran , Amir Goldstein , Andi Kleen , Mingming Cao , Joel Becker , linux-ext4@vger.kernel.org, Coly Li To: Andreas Dilger , Theodore Tso , "Darrick J. Wong" Return-path: Received: from e6.ny.us.ibm.com ([32.97.182.146]:41840 "EHLO e6.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752879Ab2AGIiN (ORCPT ); Sat, 7 Jan 2012 03:38:13 -0500 Received: from /spool/local by e6.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sat, 7 Jan 2012 03:38:12 -0500 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay04.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q078bRRx332514 for ; Sat, 7 Jan 2012 03:37:27 -0500 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q078bQei001788 for ; Sat, 7 Jan 2012 03:37:27 -0500 In-Reply-To: <20120107083256.25788.41238.stgit@elm3c44.beaverton.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Define flags and change journal structure definitions to support v2 journal checksumming. Signed-off-by: Darrick J. Wong --- lib/ext2fs/kernel-jbd.h | 30 +++++++++++++++++++++++++++--- 1 files changed, 27 insertions(+), 3 deletions(-) diff --git a/lib/ext2fs/kernel-jbd.h b/lib/ext2fs/kernel-jbd.h index 066c031..570bfa6 100644 --- a/lib/ext2fs/kernel-jbd.h +++ b/lib/ext2fs/kernel-jbd.h @@ -114,12 +114,24 @@ typedef struct journal_header_s #define JBD2_CRC32_CHKSUM 1 #define JBD2_MD5_CHKSUM 2 #define JBD2_SHA1_CHKSUM 3 +#define JBD2_CRC32C_CHKSUM 4 #define JBD2_CRC32_CHKSUM_SIZE 4 #define JBD2_CHECKSUM_BYTES (32 / sizeof(__u32)) /* * Commit block header for storing transactional checksums: + * + * NOTE: If FEATURE_COMPAT_CHECKSUM (checksum v1) is set, the h_chksum* + * fields are used to store a checksum of the descriptor and data blocks. + * + * If FEATURE_INCOMPAT_CSUM_V2 (checksum v2) is set, then the h_chksum + * field is used to store crc32c(uuid+commit_block). Each journal metadata + * block gets its own checksum, and data block checksums are stored in + * journal_block_tag (in the descriptor). The other h_chksum* fields are + * not used. + * + * Checksum v1 and v2 are mutually exclusive features. */ struct commit_header { __u32 h_magic; @@ -141,11 +153,17 @@ typedef struct journal_block_tag_s __u32 t_blocknr; /* The on-disk block number */ __u32 t_flags; /* See below */ __u32 t_blocknr_high; /* most-significant high 32bits. */ + __u32 t_checksum; /* crc32c(uuid+seq+block) */ } journal_block_tag_t; #define JBD_TAG_SIZE64 (sizeof(journal_block_tag_t)) #define JBD_TAG_SIZE32 (8) +/* Tail of descriptor block, for checksumming */ +struct journal_block_tail { + __u32 t_checksum; +}; + /* * The revoke descriptor: used on disk to describe a series of blocks to * be revoked from the log @@ -156,6 +174,10 @@ typedef struct journal_revoke_header_s int r_count; /* Count of bytes used in the block */ } journal_revoke_header_t; +/* Tail of revoke block, for checksumming */ +struct journal_revoke_tail { + __u32 r_checksum; +}; /* Definitions for the journal tag flags word: */ #define JFS_FLAG_ESCAPE 1 /* on-disk block is escaped */ @@ -205,7 +227,10 @@ typedef struct journal_superblock_s __u32 s_max_trans_data; /* Limit of data blocks per trans. */ /* 0x0050 */ - __u32 s_padding[44]; + __u8 s_checksum_type; /* checksum type */ + __u8 s_padding2[3]; + __u32 s_padding[42]; + __u32 s_checksum; /* crc32c(superblock) */ /* 0x0100 */ __u8 s_users[16*48]; /* ids of all fs'es sharing the log */ @@ -224,11 +249,10 @@ typedef struct journal_superblock_s #define JFS_FEATURE_COMPAT_CHECKSUM 0x00000001 -#define JFS_FEATURE_INCOMPAT_REVOKE 0x00000001