xfs: fix broken bhold behavior in xrep_roll_ag_trans

In xrep_roll_ag_trans, the transaction roll will always set sc->tp to
the new transaction, even if committing the old one fails.  A bare
transaction roll leaves the buffer(s) locked but not joined to the new
transaction, so it's not necessary to release the hold if the roll
fails.  Remove the incorrect xfs_trans_bhold_release calls.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

fs/xfs/scrub/repair.c

@@ -136,10 +136,16 @@ xrep_roll_ag_trans(
 	if (sc->sa.agfl_bp)
 		xfs_trans_bhold(sc->tp, sc->sa.agfl_bp);
 
-	/* Roll the transaction. */
+	/*
+	 * Roll the transaction.  We still own the buffer and the buffer lock
+	 * regardless of whether or not the roll succeeds.  If the roll fails,
+	 * the buffers will be released during teardown on our way out of the
+	 * kernel.  If it succeeds, we join them to the new transaction and
+	 * move on.
+	 */
 	error = xfs_trans_roll(&sc->tp);
 	if (error)
-		goto out_release;
+		return error;
 
 	/* Join AG headers to the new transaction. */
 	if (sc->sa.agi_bp)
@@ -150,21 +156,6 @@ xrep_roll_ag_trans(
 		xfs_trans_bjoin(sc->tp, sc->sa.agfl_bp);
 
 	return 0;
-
-out_release:
-	/*
-	 * Rolling failed, so release the hold on the buffers.  The
-	 * buffers will be released during teardown on our way out
-	 * of the kernel.
-	 */
-	if (sc->sa.agi_bp)
-		xfs_trans_bhold_release(sc->tp, sc->sa.agi_bp);
-	if (sc->sa.agf_bp)
-		xfs_trans_bhold_release(sc->tp, sc->sa.agf_bp);
-	if (sc->sa.agfl_bp)
-		xfs_trans_bhold_release(sc->tp, sc->sa.agfl_bp);
-
-	return error;
 }
 
 /*