[SCSI] libfc: export seq_release() for users of seq_assign()

Target modules using lport->tt.seq_assign() get a hold on the
exchange but have no way of releasing it.  Add that.

Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c
index 1f124c0..a3d6402 100644
--- a/drivers/scsi/libfc/fc_exch.c
+++ b/drivers/scsi/libfc/fc_exch.c
@@ -1282,6 +1282,8 @@
  * @fp:    The request frame
  *
  * On success, the sequence pointer will be returned and also in fr_seq(@fp).
+ * A reference will be held on the exchange/sequence for the caller, which
+ * must call fc_seq_release().
  */
 static struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp)
 {
@@ -1299,6 +1301,15 @@
 }
 
 /**
+ * fc_seq_release() - Release the hold
+ * @sp:    The sequence.
+ */
+static void fc_seq_release(struct fc_seq *sp)
+{
+	fc_exch_release(fc_seq_exch(sp));
+}
+
+/**
  * fc_exch_recv_req() - Handler for an incoming request
  * @lport: The local port that received the request
  * @mp:	   The EM that the exchange is on
@@ -2369,6 +2380,9 @@
 	if (!lport->tt.seq_assign)
 		lport->tt.seq_assign = fc_seq_assign;
 
+	if (!lport->tt.seq_release)
+		lport->tt.seq_release = fc_seq_release;
+
 	return 0;
 }
 EXPORT_SYMBOL(fc_exch_init);