From: Tao Ma Date: Mon, 9 Jul 2012 20:29:27 +0000 (-0400) Subject: ext4: use s_csum_seed instead of i_csum_seed for xattr block X-Git-Tag: v3.6-rc1~69^2~17 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=41eb70dde42b2360074a559a6f1fc49860a50179;p=pandora-kernel.git ext4: use s_csum_seed instead of i_csum_seed for xattr block In xattr block operation, we use h_refcount to indicate whether the xattr block is shared among many inodes. And xattr block csum uses s_csum_seed if it is shared and i_csum_seed if it belongs to one inode. But this has a problem. So consider the block is shared first bewteen inode A and B, and B has some xattr update and CoW the xattr block. When it updates the *old* xattr block(because of the h_refcount change) and calls ext4_xattr_release_block, we has no idea that inode A is the real owner of the *old* xattr block and we can't use the i_csum_seed of inode A either in xattr block csum calculation. And I don't think we have an easy way to find inode A. So this patch just removes the tricky i_csum_seed and we now uses s_csum_seed every time for the xattr block csum. The corresponding patch for the e2fsprogs will be sent in another patch. This is spotted by xfstests 117. Signed-off-by: Tao Ma Signed-off-by: "Theodore Ts'o" Acked-by: Darrick J. Wong --- Reading git-diff-tree failed