jbd2: checksum journal superblock

Calculate and verify a checksum covering the journal superblock.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 71e77dddebf1..a9632bc55d97 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;
 };
 
 /*