From: "Darrick J. Wong" <djwong@us.ibm.com>
To: Andreas Dilger <adilger.kernel@dilger.ca>,
Theodore Tso <tytso@mit.edu>,
"Darrick J. Wong" <djwong@us.ibm.com>
Cc: Sunil Mushran <sunil.mushran@oracle.com>,
Martin K Petersen <martin.petersen@oracle.com>,
Greg Freemyer <greg.freemyer@gmail.com>,
Amir Goldstein <amir73il@gmail.com>,
linux-kernel <linux-kernel@vger.kernel.org>,
Andi Kleen <andi@firstfloor.org>, Mingming Cao <cmm@us.ibm.com>,
Joel Becker <jlbec@evilplan.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-ext4@vger.kernel.org, Coly Li <colyli@gmail.com>
Subject: [PATCH 18/23] jbd2: Update structure definitions and flags to support extended checksumming
Date: Tue, 13 Dec 2011 16:48:17 -0800 [thread overview]
Message-ID: <20111214004817.28243.43348.stgit@elm3c44.beaverton.ibm.com> (raw)
In-Reply-To: <20111214004613.28243.54122.stgit@elm3c44.beaverton.ibm.com>
Add structure definitions, flags, and constants to extend checksum protection
to all journal blocks.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
---
fs/jbd2/journal.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/jbd2.h | 3 +++
2 files changed, 53 insertions(+), 0 deletions(-)
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index bb7f03f..bc80533 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -109,6 +109,34 @@ int jbd2_verify_csum_type(journal_t *j, journal_superblock_t *sb)
return sb->s_checksum_type == JBD2_CRC32C_CHKSUM;
}
+static __u32 jbd2_superblock_csum(journal_t *j, journal_superblock_t *sb)
+{
+ __u32 csum, old_csum;
+
+ old_csum = sb->s_checksum;
+ sb->s_checksum = 0;
+ csum = jbd2_chksum(j, ~0, (char *)sb, sizeof(journal_superblock_t));
+ sb->s_checksum = old_csum;
+
+ return cpu_to_be32(csum);
+}
+
+int jbd2_superblock_csum_verify(journal_t *j, journal_superblock_t *sb)
+{
+ if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2))
+ return 1;
+
+ return sb->s_checksum == jbd2_superblock_csum(j, sb);
+}
+
+void jbd2_superblock_csum_set(journal_t *j, journal_superblock_t *sb)
+{
+ if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2))
+ return;
+
+ sb->s_checksum = jbd2_superblock_csum(j, sb);
+}
+
/*
* Helper function used to manage commit timeouts
*/
@@ -1178,6 +1206,7 @@ void jbd2_journal_update_superblock(journal_t *journal, int wait)
sb->s_sequence = cpu_to_be32(journal->j_tail_sequence);
sb->s_start = cpu_to_be32(journal->j_tail);
sb->s_errno = cpu_to_be32(journal->j_errno);
+ jbd2_superblock_csum_set(journal, sb);
read_unlock(&journal->j_state_lock);
BUFFER_TRACE(bh, "marking dirty");
@@ -1295,6 +1324,17 @@ static int journal_get_superblock(journal_t *journal)
}
}
+ /* Check superblock checksum */
+ if (!jbd2_superblock_csum_verify(journal, sb)) {
+ printk(KERN_ERR "JBD: journal checksum error\n");
+ goto out;
+ }
+
+ /* Precompute checksum seed for all metadata */
+ if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2))
+ journal->j_csum_seed = jbd2_chksum(journal, ~0, sb->s_uuid,
+ sizeof(sb->s_uuid));
+
set_buffer_verified(bh);
return 0;
@@ -1581,6 +1621,13 @@ int jbd2_journal_set_features (journal_t *journal, unsigned long compat,
return 0;
}
}
+
+ /* Precompute checksum seed for all metadata */
+ if (JBD2_HAS_INCOMPAT_FEATURE(journal,
+ JBD2_FEATURE_INCOMPAT_CSUM_V2))
+ journal->j_csum_seed = jbd2_chksum(journal, ~0,
+ sb->s_uuid,
+ sizeof(sb->s_uuid));
}
/* If enabling v1 checksums, downgrade superblock */
@@ -1591,6 +1638,7 @@ int jbd2_journal_set_features (journal_t *journal, unsigned long compat,
sb->s_feature_compat |= cpu_to_be32(compat);
sb->s_feature_ro_compat |= cpu_to_be32(ro);
sb->s_feature_incompat |= cpu_to_be32(incompat);
+ jbd2_journal_update_superblock(journal, 0);
return 1;
#undef COMPAT_FEATURE_ON
@@ -1621,6 +1669,7 @@ void jbd2_journal_clear_features(journal_t *journal, unsigned long compat,
sb->s_feature_compat &= ~cpu_to_be32(compat);
sb->s_feature_ro_compat &= ~cpu_to_be32(ro);
sb->s_feature_incompat &= ~cpu_to_be32(incompat);
+ jbd2_journal_update_superblock(journal, 0);
}
EXPORT_SYMBOL(jbd2_journal_clear_features);
@@ -1669,6 +1718,7 @@ static int journal_convert_superblock_v1(journal_t *journal,
sb->s_nr_users = cpu_to_be32(1);
sb->s_header.h_blocktype = cpu_to_be32(JBD2_SUPERBLOCK_V2);
+ jbd2_superblock_csum_set(journal, sb);
journal->j_format_version = 2;
bh = journal->j_sb_buffer;
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 5b2abf9..51d4a0b 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -969,6 +969,9 @@ struct journal_s
/* Reference to checksum algorithm driver via cryptoapi */
struct crypto_shash *j_chksum_driver;
+
+ /* Precomputed journal UUID checksum for seeding other checksums */
+ __u32 j_csum_seed;
};
/*
next prev parent reply other threads:[~2011-12-14 0:48 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-12-14 0:46 [PATCH v2.2 00/23] ext4: Add metadata checksumming Darrick J. Wong
2011-12-14 0:46 ` [PATCH 01/23] ext4: Create a new BH_Verified flag to avoid unnecessary metadata validation Darrick J. Wong
2011-12-14 0:46 ` [PATCH 03/23] ext4: Record the checksum algorithm in use in the superblock Darrick J. Wong
2011-12-14 0:46 ` [PATCH 04/23] ext4: Only call out to crc32c if necessary Darrick J. Wong
2011-12-14 0:47 ` [PATCH 13/23] ext4: Add new feature to make block group checksums use metadata_csum algorithm Darrick J. Wong
2011-12-14 0:47 ` [PATCH 14/23] ext4: Add checksums to the MMP block Darrick J. Wong
2011-12-14 0:47 ` [PATCH 15/23] jbd2: Change disk layout for metadata checksumming Darrick J. Wong
2011-12-14 0:48 ` [PATCH 16/23] jbd2: Enable journal clients to enable v2 checksumming Darrick J. Wong
2011-12-14 0:48 ` [PATCH 17/23] jbd2: Grab a reference to the crc32c driver only when necessary Darrick J. Wong
2011-12-14 0:48 ` Darrick J. Wong [this message]
2011-12-14 0:48 ` [PATCH 19/23] jbd2: Checksum revocation blocks Darrick J. Wong
2011-12-14 0:48 ` [PATCH 20/23] jbd2: Checksum descriptor blocks Darrick J. Wong
2011-12-14 0:48 ` [PATCH 21/23] jbd2: Checksum commit blocks Darrick J. Wong
2011-12-14 0:48 ` [PATCH 22/23] jbd2: Checksum data blocks that are stored in the journal Darrick J. Wong
2011-12-14 0:48 ` [PATCH 23/23] ext4/jbd2: Add metadata checksumming to the list of supported features Darrick J. Wong
2011-12-14 1:10 ` [PATCH v2.2 00/23] ext4: Add metadata checksumming Darrick J. Wong
2011-12-14 1:31 ` Darrick J. Wong
2012-01-06 18:46 ` Andreas Dilger
2012-01-06 18:57 ` Darrick J. Wong
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20111214004817.28243.43348.stgit@elm3c44.beaverton.ibm.com \
--to=djwong@us.ibm.com \
--cc=adilger.kernel@dilger.ca \
--cc=amir73il@gmail.com \
--cc=andi@firstfloor.org \
--cc=cmm@us.ibm.com \
--cc=colyli@gmail.com \
--cc=greg.freemyer@gmail.com \
--cc=jlbec@evilplan.org \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=martin.petersen@oracle.com \
--cc=sunil.mushran@oracle.com \
--cc=tytso@mit.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).