xfs: add pre-write metadata buffer verifier callbacks

These verifiers are essentially the same code as the read verifiers,
but do not require ioend processing. Hence factor the read verifier
functions and add a new write verifier wrapper that is used as the
callback.

This is done as one large patch for all verifiers rather than one
patch per verifier as the change is largely mechanical. This
includes hooking up the write verifier via the read verifier
function.

Hooking up the write verifier for buffers obtained via
xfs_trans_get_buf() will be done in a separate patch as that touches
code in many different places rather than just the verifier
functions.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

1 files changed, 16 insertions, 1 deletions

diff --git a/fs/xfs/xfs_ialloc.c b/fs/xfs/xfs_ialloc.c
index 5bd255e5f7b8..070f41845572 100644
--- a/fs/xfs/xfs_ialloc.c
+++ b/fs/xfs/xfs_ialloc.c
@@ -1473,7 +1473,7 @@ xfs_check_agi_unlinked(
 #endif
 
 static void
-xfs_agi_read_verify(
+xfs_agi_verify(
         struct xfs_buf  *bp)
 {
         struct xfs_mount *mp = bp->b_target->bt_mount;
@@ -1502,6 +1502,21 @@ xfs_agi_read_verify(
                 xfs_buf_ioerror(bp, EFSCORRUPTED);
         }
         xfs_check_agi_unlinked(agi);
+}
+
+static void
+xfs_agi_write_verify(
+        struct xfs_buf  *bp)
+{
+        xfs_agi_verify(bp);
+}
+
+void
+xfs_agi_read_verify(
+        struct xfs_buf  *bp)
+{
+        xfs_agi_verify(bp);
+        bp->b_pre_io = xfs_agi_write_verify;
         bp->b_iodone = NULL;
         xfs_buf_ioend(bp, 0);
 }