[PATCH 3/6] xfs: inode unlinked list needs to recalculate the inode CRC

Dave Chinner
2013-06-03T05:29:09Z

From: Dave Chinner <dchinner@redhat.com>

The inode unlinked list manipulations operate directly on the inode
buffer, and so bypass the inode CRC calculation mechanisms. Hence an
inode on the unlinked list has an invalid CRC. Fix this by
recalculating the CRC whenever we modify an unlinked list pointer in
an inode, ncluding during log recovery. This is trivial to do and
results in unlinked list operations always leaving a consistent
inode in the buffer.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/xfs_inode.c | 16 ++++++++++++++++
fs/xfs/xfs_log_recover.c | 9 +++++++++
2 files changed, 25 insertions(+)

diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index efbe1ac..c50e785 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -1638,6 +1638,10 @@ xfs_iunlink(
dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
offset = ip->i_imap.im_boffset +
offsetof(xfs_dinode_t, di_next_unlinked);
+
+ /* need to recalc the inode CRC if appropriate */
+ xfs_dinode_calc_crc(mp, dip);
+
xfs_trans_inode_buf(tp, ibp);
xfs_trans_log_buf(tp, ibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
@@ -1723,6 +1727,10 @@ xfs_iunlink_remove(
dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
offset = ip->i_imap.im_boffset +
offsetof(xfs_dinode_t, di_next_unlinked);
+
+ /* need to recalc the inode CRC if appropriate */
+ xfs_dinode_calc_crc(mp, dip);
+
xfs_trans_inode_buf(tp, ibp);
xfs_trans_log_buf(tp, ibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
@@ -1796,6 +1804,10 @@ xfs_iunlink_remove(
dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
offset = ip->i_imap.im_boffset +
offsetof(xfs_dinode_t, di_next_unlinked);
+
+ /* need to recalc the inode CRC if appropriate */
+ xfs_dinode_calc_crc(mp, dip);
+
xfs_trans_inode_buf(tp, ibp);
xfs_trans_log_buf(tp, ibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
@@ -1809,6 +1821,10 @@ xfs_iunlink_remove(
last_dip->di_next_unlinked = cpu_to_be32(next_agino);
ASSERT(next_agino != 0);
offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
+
+ /* need to recalc the inode CRC if appropriate */
+ xfs_dinode_calc_crc(mp, dip);
+
xfs_trans_inode_buf(tp, last_ibp);
xfs_trans_log_buf(tp, last_ibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 83088d9..45a85ff 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -1912,6 +1912,15 @@ xlog_recover_do_inode_buffer(
buffer_nextp = (xfs_agino_t *)xfs_buf_offset(bp,
next_unlinked_offset);
*buffer_nextp = *logged_nextp;
+
+ /*
+ * If necessary, recalculate the CRC in the on-disk inode. We
+ * have to leave the inode in a consistent state for whoever
+ * reads it next....
+ */
+ xfs_dinode_calc_crc(mp, (struct xfs_dinode *)
+ xfs_buf_offset(bp, i * mp->m_sb.sb_inodesize));
+
}

return 0;
--
1.7.10.4