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>

---
 drivers/scsi/libfc/fc_exch.c |   14 ++++++++++++++
 include/scsi/libfc.h         |    7 +++++++
 2 files changed, 21 insertions(+), 0 deletions(-)


---
diff --git a/drivers/scsi/libfc/fc_exch.c b/drivers/scsi/libfc/fc_exch.c
index 0000ddf..0deb901 100644
--- a/drivers/scsi/libfc/fc_exch.c
+++ b/drivers/scsi/libfc/fc_exch.c
@@ -1252,6 +1252,8 @@ free:
  * @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)
 {
@@ -1269,6 +1271,15 @@ static struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp)
 }
 
 /**
+ * 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
@@ -2337,6 +2348,9 @@ int fc_exch_init(struct fc_lport *lport)
 	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);
diff --git a/include/scsi/libfc.h b/include/scsi/libfc.h
index af8a6e8..875e3a8 100644
--- a/include/scsi/libfc.h
+++ b/include/scsi/libfc.h
@@ -574,6 +574,13 @@ struct libfc_function_template {
 			     void *arg);
 
 	/*
+	 * Release the reference on the sequence returned by seq_assign().
+	 *
+	 * STATUS: OPTIONAL
+	 */
+	void (*seq_release)(struct fc_seq *);
+
+	/*
 	 * Reset an exchange manager, completing all sequences and exchanges.
 	 * If s_id is non-zero, reset only exchanges originating from that FID.
 	 * If d_id is non-zero, reset only exchanges sending to that FID.