[SCSI] libfc: don't require a local exchange for incoming requests

Incoming requests shouldn't require a local exchange if we're
just going to reply with one or two frames and don't expect
anything further.  Don't allocate exchanges for such requests
until requested by the upper-layer protocol.

The sequence is always NULL for new requests, so remove
that as an argument to request handlers.

Also change the first argument to lport->tt.seq_els_rsp_send
from the sequence pointer to the received frame pointer, to
supply the exchange IDs and destination ID info.
Signed-off-by: Joe Eykholt <jeykholt@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

drivers/scsi/fcoe/libfcoe.c

@@ -2341,20 +2341,19 @@ static int fcoe_ctlr_vn_recv(struct fcoe_ctlr *fip, struct sk_buff *skb)
 
 /**
  * fcoe_ctlr_disc_recv - discovery receive handler for VN2VN mode.
- * @fip: The FCoE controller
+ * @lport: The local port
+ * @fp: The received frame
  *
  * This should never be called since we don't see RSCNs or other
  * fabric-generated ELSes.
  */
-static void fcoe_ctlr_disc_recv(struct fc_seq *seq, struct fc_frame *fp,
-				struct fc_lport *lport)
+static void fcoe_ctlr_disc_recv(struct fc_lport *lport, struct fc_frame *fp)
 {
 	struct fc_seq_els_data rjt_data;
 
-	rjt_data.fp = NULL;
 	rjt_data.reason = ELS_RJT_UNSUP;
 	rjt_data.explan = ELS_EXPL_NONE;
-	lport->tt.seq_els_rsp_send(seq, ELS_LS_RJT, &rjt_data);
+	lport->tt.seq_els_rsp_send(fp, ELS_LS_RJT, &rjt_data);
 	fc_frame_free(fp);
 }
 

drivers/scsi/libfc/fc_disc.c

@@ -75,15 +75,13 @@ void fc_disc_stop_rports(struct fc_disc *disc)
 
 /**
  * fc_disc_recv_rscn_req() - Handle Registered State Change Notification (RSCN)
- * @sp:	   The sequence of the RSCN exchange
+ * @disc:  The discovery object to which the RSCN applies
  * @fp:	   The RSCN frame
- * @lport: The local port that the request will be sent on
  *
  * Locking Note: This function expects that the disc_mutex is locked
  *		 before it is called.
  */
-static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp,
-				  struct fc_disc *disc)
+static void fc_disc_recv_rscn_req(struct fc_disc *disc, struct fc_frame *fp)
 {
 	struct fc_lport *lport;
 	struct fc_els_rscn *rp;
@@ -151,7 +149,7 @@ static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp,
 			break;
 		}
 	}
-	lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL);
+	lport->tt.seq_els_rsp_send(fp, ELS_LS_ACC, NULL);
 
 	/*
 	 * If not doing a complete rediscovery, do GPN_ID on
@@ -177,25 +175,22 @@ static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp,
 	return;
 reject:
 	FC_DISC_DBG(disc, "Received a bad RSCN frame\n");
-	rjt_data.fp = NULL;
 	rjt_data.reason = ELS_RJT_LOGIC;
 	rjt_data.explan = ELS_EXPL_NONE;
-	lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+	lport->tt.seq_els_rsp_send(fp, ELS_LS_RJT, &rjt_data);
 	fc_frame_free(fp);
 }
 
 /**
  * fc_disc_recv_req() - Handle incoming requests
- * @sp:	   The sequence of the request exchange
- * @fp:	   The request frame
  * @lport: The local port receiving the request
+ * @fp:	   The request frame
  *
  * Locking Note: This function is called from the EM and will lock
  *		 the disc_mutex before calling the handler for the
  *		 request.
  */
-static void fc_disc_recv_req(struct fc_seq *sp, struct fc_frame *fp,
-			     struct fc_lport *lport)
+static void fc_disc_recv_req(struct fc_lport *lport, struct fc_frame *fp)
 {
 	u8 op;
 	struct fc_disc *disc = &lport->disc;
@@ -204,7 +199,7 @@ static void fc_disc_recv_req(struct fc_seq *sp, struct fc_frame *fp,
 	switch (op) {
 	case ELS_RSCN:
 		mutex_lock(&disc->disc_mutex);
-		fc_disc_recv_rscn_req(sp, fp, disc);
+		fc_disc_recv_rscn_req(disc, fp);
 		mutex_unlock(&disc->disc_mutex);
 		break;
 	default:

drivers/scsi/libfc/fc_lport.c

@@ -375,34 +375,31 @@ static void fc_lport_add_fc4_type(struct fc_lport *lport, enum fc_fh_type type)
 
 /**
  * fc_lport_recv_rlir_req() - Handle received Registered Link Incident Report.
- * @sp:	   The sequence in the RLIR exchange
- * @fp:	   The RLIR request frame
  * @lport: Fibre Channel local port recieving the RLIR
+ * @fp:	   The RLIR request frame
  *
  * Locking Note: The lport lock is expected to be held before calling
  * this function.
  */
-static void fc_lport_recv_rlir_req(struct fc_seq *sp, struct fc_frame *fp,
-				   struct fc_lport *lport)
+static void fc_lport_recv_rlir_req(struct fc_lport *lport, struct fc_frame *fp)
 {
 	FC_LPORT_DBG(lport, "Received RLIR request while in state %s\n",
 		     fc_lport_state(lport));
 
-	lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL);
+	lport->tt.seq_els_rsp_send(fp, ELS_LS_ACC, NULL);
 	fc_frame_free(fp);
 }
 
 /**
  * fc_lport_recv_echo_req() - Handle received ECHO request
- * @sp:	   The sequence in the ECHO exchange
- * @fp:	   ECHO request frame
  * @lport: The local port recieving the ECHO
+ * @fp:	   ECHO request frame
  *
  * Locking Note: The lport lock is expected to be held before calling
  * this function.
  */
-static void fc_lport_recv_echo_req(struct fc_seq *sp, struct fc_frame *in_fp,
-				   struct fc_lport *lport)
+static void fc_lport_recv_echo_req(struct fc_lport *lport,
+				   struct fc_frame *in_fp)
 {
 	struct fc_frame *fp;
 	unsigned int len;
@@ -431,15 +428,14 @@ static void fc_lport_recv_echo_req(struct fc_seq *sp, struct fc_frame *in_fp,
 
 /**
  * fc_lport_recv_rnid_req() - Handle received Request Node ID data request
- * @sp:	   The sequence in the RNID exchange
- * @fp:	   The RNID request frame
  * @lport: The local port recieving the RNID
+ * @fp:	   The RNID request frame
  *
  * Locking Note: The lport lock is expected to be held before calling
  * this function.
  */
-static void fc_lport_recv_rnid_req(struct fc_seq *sp, struct fc_frame *in_fp,
-				   struct fc_lport *lport)
+static void fc_lport_recv_rnid_req(struct fc_lport *lport,
+				   struct fc_frame *in_fp)
 {
 	struct fc_frame *fp;
 	struct fc_els_rnid *req;
@@ -457,10 +453,9 @@ static void fc_lport_recv_rnid_req(struct fc_seq *sp, struct fc_frame *in_fp,
 
 	req = fc_frame_payload_get(in_fp, sizeof(*req));
 	if (!req) {
-		rjt_data.fp = NULL;
 		rjt_data.reason = ELS_RJT_LOGIC;
 		rjt_data.explan = ELS_EXPL_NONE;
-		lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+		lport->tt.seq_els_rsp_send(in_fp, ELS_LS_RJT, &rjt_data);
 	} else {
 		fmt = req->rnid_fmt;
 		len = sizeof(*rp);
@@ -492,17 +487,15 @@ static void fc_lport_recv_rnid_req(struct fc_seq *sp, struct fc_frame *in_fp,
 
 /**
  * fc_lport_recv_logo_req() - Handle received fabric LOGO request
- * @sp:	   The sequence in the LOGO exchange
- * @fp:	   The LOGO request frame
  * @lport: The local port recieving the LOGO
+ * @fp:	   The LOGO request frame
  *
  * Locking Note: The lport lock is exected to be held before calling
  * this function.
  */
-static void fc_lport_recv_logo_req(struct fc_seq *sp, struct fc_frame *fp,
-				   struct fc_lport *lport)
+static void fc_lport_recv_logo_req(struct fc_lport *lport, struct fc_frame *fp)
 {
-	lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL);
+	lport->tt.seq_els_rsp_send(fp, ELS_LS_ACC, NULL);
 	fc_lport_enter_reset(lport);
 	fc_frame_free(fp);
 }
@@ -773,9 +766,8 @@ EXPORT_SYMBOL(fc_lport_set_local_id);
 
 /**
  * fc_lport_recv_flogi_req() - Receive a FLOGI request
- * @sp_in: The sequence the FLOGI is on
- * @rx_fp: The FLOGI frame
  * @lport: The local port that recieved the request
+ * @rx_fp: The FLOGI frame
  *
  * A received FLOGI request indicates a point-to-point connection.
  * Accept it with the common service parameters indicating our N port.
@@ -784,13 +776,11 @@ EXPORT_SYMBOL(fc_lport_set_local_id);
  * Locking Note: The lport lock is expected to be held before calling
  * this function.
  */
-static void fc_lport_recv_flogi_req(struct fc_seq *sp_in,
-				    struct fc_frame *rx_fp,
-				    struct fc_lport *lport)
+static void fc_lport_recv_flogi_req(struct fc_lport *lport,
+				    struct fc_frame *rx_fp)
 {
 	struct fc_frame *fp;
 	struct fc_frame_header *fh;
-	struct fc_seq *sp;
 	struct fc_els_flogi *flp;
 	struct fc_els_flogi *new_flp;
 	u64 remote_wwpn;
@@ -850,16 +840,13 @@ static void fc_lport_recv_flogi_req(struct fc_seq *sp_in,
 	}
 	fc_lport_ptp_setup(lport, remote_fid, remote_wwpn,
 			   get_unaligned_be64(&flp->fl_wwnn));
-
 out:
-	sp = fr_seq(rx_fp);
 	fc_frame_free(rx_fp);
 }
 
 /**
  * fc_lport_recv_req() - The generic lport request handler
  * @lport: The local port that received the request
- * @sp:	   The sequence the request is on
  * @fp:	   The request frame
  *
  * This function will see if the lport handles the request or
@@ -868,11 +855,10 @@ static void fc_lport_recv_flogi_req(struct fc_seq *sp_in,
  * Locking Note: This function should not be called with the lport
  *		 lock held becuase it will grab the lock.
  */
-static void fc_lport_recv_req(struct fc_lport *lport, struct fc_seq *sp,
-			      struct fc_frame *fp)
+static void fc_lport_recv_req(struct fc_lport *lport, struct fc_frame *fp)
 {
 	struct fc_frame_header *fh = fc_frame_header_get(fp);
-	void (*recv) (struct fc_seq *, struct fc_frame *, struct fc_lport *);
+	void (*recv)(struct fc_lport *, struct fc_frame *);
 
 	mutex_lock(&lport->lp_mutex);
 
@@ -912,19 +898,13 @@ static void fc_lport_recv_req(struct fc_lport *lport, struct fc_seq *sp,
 			break;
 		}
 
-		recv(sp, fp, lport);
+		recv(lport, fp);
 	} else {
 		FC_LPORT_DBG(lport, "dropping invalid frame (eof %x)\n",
 			     fr_eof(fp));
 		fc_frame_free(fp);
 	}
 	mutex_unlock(&lport->lp_mutex);
-
-	/*
-	 *  The common exch_done for all request may not be good
-	 *  if any request requires longer hold on exhange. XXX
-	 */
-	lport->tt.exch_done(sp);
 }
 
 /**

include/scsi/libfc.h

@@ -249,14 +249,12 @@ struct fcoe_dev_stats {
 
 /**
  * struct fc_seq_els_data - ELS data used for passing ELS specific responses
- * @fp:     The ELS frame
  * @reason: The reason for rejection
  * @explan: The explaination of the rejection
  *
  * Mainly used by the exchange manager layer.
  */
 struct fc_seq_els_data {
-	struct fc_frame *fp;
 	enum fc_els_rjt_reason reason;
 	enum fc_els_rjt_explan explan;
 };
@@ -519,12 +517,11 @@ struct libfc_function_template {
 			struct fc_frame *);
 
 	/*
-	 * Send an ELS response using infomation from a previous
-	 * exchange and sequence.
+	 * Send an ELS response using infomation from the received frame.
 	 *
 	 * STATUS: OPTIONAL
 	 */
-	void (*seq_els_rsp_send)(struct fc_seq *, enum fc_els_cmd,
+	void (*seq_els_rsp_send)(struct fc_frame *, enum fc_els_cmd,
 				 struct fc_seq_els_data *);
 
 	/*
@@ -583,8 +580,7 @@ struct libfc_function_template {
 	 *
 	 * STATUS: OPTIONAL
 	 */
-	void (*lport_recv)(struct fc_lport *, struct fc_seq *,
-			   struct fc_frame *);
+	void (*lport_recv)(struct fc_lport *, struct fc_frame *);
 
 	/*
 	 * Reset the local port.
@@ -646,8 +642,7 @@ struct libfc_function_template {
 	 *
 	 * STATUS: OPTIONAL
 	 */
-	void (*rport_recv_req)(struct fc_seq *, struct fc_frame *,
-			       struct fc_lport *);
+	void (*rport_recv_req)(struct fc_lport *, struct fc_frame *);
 
 	/*
 	 * lookup an rport by it's port ID.
@@ -693,8 +688,7 @@ struct libfc_function_template {
 	 *
 	 * STATUS: OPTIONAL
 	 */
-	void (*disc_recv_req)(struct fc_seq *, struct fc_frame *,
-			      struct fc_lport *);
+	void (*disc_recv_req)(struct fc_lport *, struct fc_frame *);
 
 	/*
 	 * Start discovery for a local port.