- Changed the identification string displayed by the ibsrpdm tool from

"Mellanox OFED SRP target" to "SCST SRP target" to reflect that this
  version of the SRP target is distributed through the SCST project.
- Added kernel parameter use_port_guid_in_session_name that allows to
  use the original session naming scheme of the SRP target. This should
  make it again possible to connect to a multiport SRP target by masking
  out redundant paths on the target.
- Made sure that whenever a login is rejected that a kernel message is
  generated (printk()) such that this information ends up in
  /var/log/messages.


git-svn-id: http://svn.code.sf.net/p/scst/svn/trunk@1055 d57e44dd-8a1f-0410-8b47-8ef2f437770f

srpt/src/ib_srpt.c

@@ -62,7 +62,7 @@
 #define SRPT_PROC_TRACE_LEVEL_NAME	"trace_level"
 #endif
 
-#define MELLANOX_SRPT_ID_STRING	"Mellanox OFED SRP target"
+#define MELLANOX_SRPT_ID_STRING	"SCST SRP target"
 
 MODULE_AUTHOR("Vu Pham");
 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol target "
@@ -85,6 +85,7 @@ struct srpt_thread {
 static u64 srpt_service_guid;
 /* List of srpt_device structures. */
 static atomic_t srpt_device_count;
+static int use_port_guid_in_session_name;
 static int thread;
 static struct srpt_thread srpt_thread;
 static DECLARE_WAIT_QUEUE_HEAD(ioctx_list_waitQ);
@@ -100,6 +101,11 @@ MODULE_PARM_DESC(thread,
 		 "Executing ioctx in thread context. Default 0, i.e. soft IRQ, "
 		 "where possible");
 
+module_param(use_port_guid_in_session_name, bool, 0444);
+MODULE_PARM_DESC(use_port_guid_in_session_name,
+		 "Use target port ID in the SCST session name such that"
+		 " redundant paths between multiport systems can be masked.");
+
 static void srpt_add_one(struct ib_device *device);
 static void srpt_remove_one(struct ib_device *device);
 static void srpt_unregister_mad_agent(struct srpt_device *sdev);
@@ -1600,8 +1606,32 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
 	u32 it_iu_len;
 	int ret = 0;
 
+#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 18)
+	WARN_ON(!sdev || !private_data);
 	if (!sdev || !private_data)
 		return -EINVAL;
+#else
+	if (WARN_ON(!sdev || !private_data))
+		return -EINVAL;
+#endif
+
+	req = (struct srp_login_req *)private_data;
+
+	it_iu_len = be32_to_cpu(req->req_it_iu_len);
+
+	printk(KERN_INFO PFX "received SRP_LOGIN_REQ with"
+	    " i_port_id 0x%llx:0x%llx, t_port_id 0x%llx:0x%llx and length %d"
+	    " on port %d (guid=0x%llx:0x%llx)\n",
+	    (unsigned long long)be64_to_cpu(*(u64 *)&req->initiator_port_id[0]),
+	    (unsigned long long)be64_to_cpu(*(u64 *)&req->initiator_port_id[8]),
+	    (unsigned long long)be64_to_cpu(*(u64 *)&req->target_port_id[0]),
+	    (unsigned long long)be64_to_cpu(*(u64 *)&req->target_port_id[8]),
+	    it_iu_len,
+	    param->port,
+	    (unsigned long long)be64_to_cpu(*(u64 *)
+				&sdev->port[param->port - 1].gid.raw[0]),
+	    (unsigned long long)be64_to_cpu(*(u64 *)
+				&sdev->port[param->port - 1].gid.raw[8]));
 
 	rsp = kzalloc(sizeof *rsp, GFP_KERNEL);
 	rej = kzalloc(sizeof *rej, GFP_KERNEL);
@@ -1612,23 +1642,12 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
 		goto out;
 	}
 
-	req = (struct srp_login_req *)private_data;
-
-	it_iu_len = be32_to_cpu(req->req_it_iu_len);
-
-	TRACE_DBG("Host login i_port_id=0x%llx:0x%llx t_port_id=0x%llx:0x%llx"
-	    " it_iu_len=%d",
-	    (unsigned long long)be64_to_cpu(*(u64 *)&req->initiator_port_id[0]),
-	    (unsigned long long)be64_to_cpu(*(u64 *)&req->initiator_port_id[8]),
-	    (unsigned long long)be64_to_cpu(*(u64 *)&req->target_port_id[0]),
-	    (unsigned long long)be64_to_cpu(*(u64 *)&req->target_port_id[8]),
-	    it_iu_len);
-
 	if (it_iu_len > MAX_MESSAGE_SIZE || it_iu_len < 64) {
 		rej->reason =
 		    cpu_to_be32(SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE);
 		ret = -EINVAL;
-		TRACE_DBG("Reject invalid it_iu_len=%d", it_iu_len);
+		printk(KERN_ERR PFX "rejected SRP_LOGIN_REQ because its"
+		       " length (%d bytes) is invalid\n", it_iu_len);
 		goto reject;
 	}
 
@@ -1661,10 +1680,17 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
 				rsp->rsp_flags =
 					SRP_LOGIN_RSP_MULTICHAN_TERMINATED;
 
-				if (prev_state == RDMA_CHANNEL_LIVE)
+				if (prev_state == RDMA_CHANNEL_LIVE) {
 					ib_send_cm_dreq(ch->cm_id, NULL, 0);
-				else if (prev_state ==
+					printk(KERN_ERR PFX "disconnected"
+					  " session %s because a new"
+					  " SRP_LOGIN_REQ has been received.\n",
+					  ch->sess_name);
+				} else if (prev_state ==
 					 RDMA_CHANNEL_CONNECTING) {
+					printk(KERN_ERR PFX "rejected"
+					  " SRP_LOGIN_REQ because another login"
+					  " request is being processed.\n");
 					ib_send_cm_rej(ch->cm_id,
 						       IB_CM_REJ_NO_RESOURCES,
 						       NULL, 0, NULL, 0);
@@ -1687,14 +1713,16 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
 		rej->reason =
 		    cpu_to_be32(SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL);
 		ret = -ENOMEM;
-		TRACE_DBG("%s", "Reject invalid target_port_id");
+		printk(KERN_ERR PFX "rejected SRP_LOGIN_REQ because it"
+		       " has an invalid target port identifier\n");
 		goto reject;
 	}
 
 	ch = kzalloc(sizeof *ch, GFP_KERNEL);
 	if (!ch) {
 		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
-		TRACE_DBG("%s", "Reject failed allocate rdma_ch");
+		printk(KERN_ERR PFX "rejected SRP_LOGIN_REQ because out of"
+		       " memory\n");
 		ret = -ENOMEM;
 		goto reject;
 	}
@@ -1711,27 +1739,50 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
 	ret = srpt_create_ch_ib(ch);
 	if (ret) {
 		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
-		TRACE_DBG("%s", "Reject failed to create rdma_ch");
+		printk(KERN_ERR PFX "rejected SRP_LOGIN_REQ because creating"
+		       " a new RDMA channel failed\n");
 		goto free_ch;
 	}
 
 	ret = srpt_ch_qp_rtr(ch, ch->qp);
 	if (ret) {
 		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
-		TRACE_DBG("Reject failed qp to rtr/rts ret=%d", ret);
+		printk(KERN_ERR PFX "rejected SRP_LOGIN_REQ because enabling"
+		       " RTR failed (error code = %d)\n", ret);
 		goto destroy_ib;
 	}
 
-	snprintf(ch->sess_name, sizeof(ch->sess_name),
-		 "0x%016llx%016llx",
-		 (unsigned long long)be64_to_cpu(*(u64 *)ch->i_port_id),
-		 (unsigned long long)be64_to_cpu(*(u64 *)(ch->i_port_id + 8)));
+	if (use_port_guid_in_session_name) {
+		/*
+		 * If the kernel module parameter use_port_guid_in_session_name
+		 * has been specified, use a combination of the target port
+		 * GUID and the initiator port ID as the session name. This
+		 * was the original behavior of the SRP target implementation
+		 * (i.e. before the SRPT was included in OFED 1.3).
+		 */
+		snprintf(ch->sess_name, sizeof(ch->sess_name),
+			 "0x%016llx%016llx",
+			 (unsigned long long)be64_to_cpu(*(u64 *)
+				&sdev->port[param->port - 1].gid.raw[8]),
+			 (unsigned long long)be64_to_cpu(*(u64 *)
+				(ch->i_port_id + 8)));
+	} else {
+		/*
+		 * Default behavior: use the initator port identifier as the
+		 * session name.
+		 */
+		snprintf(ch->sess_name, sizeof(ch->sess_name),
+			 "0x%016llx%016llx",
+			 (unsigned long long)be64_to_cpu(*(u64 *)ch->i_port_id),
+			 (unsigned long long)be64_to_cpu(*(u64 *)
+				 (ch->i_port_id + 8)));
+	}
 
 	TRACE_DBG("registering session %s", ch->sess_name);
 
 	BUG_ON(!sdev->scst_tgt);
 	ch->scst_sess = scst_register_session(sdev->scst_tgt, 0, ch->sess_name,
-				  NULL, NULL);
+					      NULL, NULL);
 	if (!ch->scst_sess) {
 		rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
 		TRACE_DBG("%s", "Failed to create scst sess");
@@ -1765,8 +1816,11 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
 	rep_param->initiator_depth = 4;
 
 	ret = ib_send_cm_rep(cm_id, rep_param);
-	if (ret)
+	if (ret) {
+		printk(KERN_ERR PFX "sending SRP_LOGIN_REQ response failed"
+		       " (error code = %d)\n", ret);
 		goto release_channel;
+	}
 
 	spin_lock_irq(&sdev->spinlock);
 	list_add_tail(&ch->list, &sdev->rch_list);