IB SRP initiator patches for kernel 3.12

index 17b58f4..aed5b75 100644
@@ -390,7 +390,7 @@ static int srp_send_req(struct srp_target_port *target)
 	req->param.responder_resources	      = 4;
 	req->param.remote_cm_response_timeout = 20;
 	req->param.local_cm_response_timeout  = 20;
-	req->param.retry_count 		      = 7;
+	req->param.retry_count                = target->tl_retry_count;
 	req->param.rnr_retry_count 	      = 7;
 	req->param.max_cm_retries 	      = 15;
 

@@ -1907,6 +1907,14 @@ static ssize_t show_comp_vector(struct device *dev,
 	return sprintf(buf, "%d\n", target->comp_vector);
 }
 
+static ssize_t show_tl_retry_count(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct srp_target_port *target = host_to_target(class_to_shost(dev));
+
+	return sprintf(buf, "%d\n", target->tl_retry_count);
+}
+
 static ssize_t show_cmd_sg_entries(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {

@@ -1934,6 +1942,7 @@ static DEVICE_ATTR(zero_req_lim,    S_IRUGO, show_zero_req_lim,	   NULL);
 static DEVICE_ATTR(local_ib_port,   S_IRUGO, show_local_ib_port,   NULL);
 static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
 static DEVICE_ATTR(comp_vector,     S_IRUGO, show_comp_vector,     NULL);
+static DEVICE_ATTR(tl_retry_count,  S_IRUGO, show_tl_retry_count,  NULL);
 static DEVICE_ATTR(cmd_sg_entries,  S_IRUGO, show_cmd_sg_entries,  NULL);
 static DEVICE_ATTR(allow_ext_sg,    S_IRUGO, show_allow_ext_sg,    NULL);
 

@@ -1949,6 +1958,7 @@ static struct device_attribute *srp_host_attrs[] = {
 	&dev_attr_local_ib_port,
 	&dev_attr_local_ib_device,
 	&dev_attr_comp_vector,
+	&dev_attr_tl_retry_count,
 	&dev_attr_cmd_sg_entries,
 	&dev_attr_allow_ext_sg,
 	NULL

@@ -2073,6 +2083,7 @@ enum {
 	SRP_OPT_ALLOW_EXT_SG	= 1 << 10,
 	SRP_OPT_SG_TABLESIZE	= 1 << 11,
 	SRP_OPT_COMP_VECTOR	= 1 << 12,
+	SRP_OPT_TL_RETRY_COUNT	= 1 << 13,
 	SRP_OPT_ALL		= (SRP_OPT_ID_EXT	|
 				   SRP_OPT_IOC_GUID	|
 				   SRP_OPT_DGID		|

@@ -2094,6 +2105,7 @@ static const match_table_t srp_opt_tokens = {
 	{ SRP_OPT_ALLOW_EXT_SG,		"allow_ext_sg=%u"	},
 	{ SRP_OPT_SG_TABLESIZE,		"sg_tablesize=%u"	},
 	{ SRP_OPT_COMP_VECTOR,		"comp_vector=%u"	},
+	{ SRP_OPT_TL_RETRY_COUNT,	"tl_retry_count=%u"	},
 	{ SRP_OPT_ERR,			NULL 			}
 };
 

@@ -2257,6 +2269,15 @@ static int srp_parse_options(const char *buf, struct srp_target_port *target)
 			target->comp_vector = token;
 			break;
 
+		case SRP_OPT_TL_RETRY_COUNT:
+			if (match_int(args, &token) || token < 2 || token > 7) {
+				pr_warn("bad tl_retry_count parameter '%s' (must be a number between 2 and 7)\n",
+					p);
+				goto out;
+			}
+			target->tl_retry_count = token;
+			break;
+
 		default:
 			pr_warn("unknown parameter or missing value '%s' in target creation request\n",
 				p);

@@ -2311,6 +2332,7 @@ static ssize_t srp_create_target(struct device *dev,
 	target->cmd_sg_cnt	= cmd_sg_entries;
 	target->sg_tablesize	= indirect_sg_entries ? : cmd_sg_entries;
 	target->allow_ext_sg	= allow_ext_sg;
+	target->tl_retry_count	= 7;
 
 	ret = srp_parse_options(buf, target);
 	if (ret)

index e641088..84d821b 100644
@@ -157,6 +157,7 @@ struct srp_target_port {
 	unsigned int		scsi_id;
 	unsigned int		sg_tablesize;
 	int			comp_vector;
+	int			tl_retry_count;
 
 	struct ib_sa_path_rec	path;
 	__be16			orig_dgid[8];

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96 lines not on this page · raw message

index 414fd02..5551f3b 100644
@@ -86,6 +86,27 @@ module_param(topspin_workarounds, int, 0444);
 MODULE_PARM_DESC(topspin_workarounds,
 		 "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
 
+static struct kernel_param_ops srp_tmo_ops;
+
+static int srp_fast_io_fail_tmo = 15;
+module_param_cb(fast_io_fail_tmo, &srp_tmo_ops, &srp_fast_io_fail_tmo,
+		S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(fast_io_fail_tmo,
+		 "Number of seconds between the observation of a transport"
+		 " layer error and failing all I/O. \"off\" means that this"
+		 " functionality is disabled.");
+
+static int srp_dev_loss_tmo = 60;
+module_param_cb(dev_loss_tmo, &srp_tmo_ops, &srp_dev_loss_tmo,
+		S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(dev_loss_tmo,
+		 "Maximum number of seconds that the SRP transport should"
+		 " insulate transport layer errors. After this time has been"
+		 " exceeded the SCSI host is removed. Should be"
+		 " between 1 and " __stringify(SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
+		 " if fast_io_fail_tmo has not been set. \"off\" means that"
+		 " this functionality is disabled.");
+
 static void srp_add_one(struct ib_device *device);
 static void srp_remove_one(struct ib_device *device);
 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr);

@@ -102,6 +123,44 @@ static struct ib_client srp_client = {
 
 static struct ib_sa_client srp_sa_client;
 
+static int srp_tmo_get(char *buffer, const struct kernel_param *kp)
+{
+	int tmo = *(int *)kp->arg;
+
+	if (tmo >= 0)
+		return sprintf(buffer, "%d", tmo);
+	else
+		return sprintf(buffer, "off");
+}
+
+static int srp_tmo_set(const char *val, const struct kernel_param *kp)
+{
+	int tmo, res;
+
+	if (strncmp(val, "off", 3) != 0) {
+		res = kstrtoint(val, 0, &tmo);
+		if (res)
+			goto out;
+	} else {
+		tmo = -1;
+	}
+	if (kp->arg == &srp_fast_io_fail_tmo)
+		res = srp_tmo_valid(tmo, srp_dev_loss_tmo);
+	else
+		res = srp_tmo_valid(srp_fast_io_fail_tmo, tmo);
+	if (res)
+		goto out;
+	*(int *)kp->arg = tmo;
+
+out:
+	return res;
+}
+
+static struct kernel_param_ops srp_tmo_ops = {
+	.get = srp_tmo_get,
+	.set = srp_tmo_set,
+};
+
 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
 {
 	return (struct srp_target_port *) host->hostdata;

@@ -689,23 +748,42 @@ static void srp_free_req(struct srp_target_port *target,
 	spin_unlock_irqrestore(&target->lock, flags);
 }
 
-static void srp_reset_req(struct srp_target_port *target, struct srp_request *req)
+static void srp_finish_req(struct srp_target_port *target,
+			   struct srp_request *req, int result)
 {
 	struct scsi_cmnd *scmnd = srp_claim_req(target, req, NULL);
 
 	if (scmnd) {
 		srp_free_req(target, req, scmnd, 0);
-		scmnd->result = DID_RESET << 16;
+		scmnd->result = result;
 		scmnd->scsi_done(scmnd);
 	}
 }
 
-static int srp_reconnect_target(struct srp_target_port *target)
+static void srp_terminate_io(struct srp_rport *rport)
 {
-	struct Scsi_Host *shost = target->scsi_host;
-	int i, ret;
+	struct srp_target_port *target = rport->lld_data;
+	int i;
+
+	for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
+		struct srp_request *req = &target->req_ring[i];
+		srp_finish_req(target, req, DID_TRANSPORT_FAILFAST << 16);
+	}
+}
 
-	scsi_target_block(&shost->shost_gendev);
+/*
+ * It is up to the caller to ensure that srp_rport_reconnect() calls are
+ * serialized and that no concurrent srp_queuecommand(), srp_abort(),
+ * srp_reset_device() or srp_reset_host() calls will occur while this function
+ * is in progress. One way to realize that is not to call this function
+ * directly but to call srp_reconnect_rport() instead since that last function
+ * serializes calls of this function via rport->mutex and also blocks
+ * srp_queuecommand() calls before invoking this function.
+ */
+static int srp_rport_reconnect(struct srp_rport *rport)
+{
+	struct srp_target_port *target = rport->lld_data;
+	int i, ret;
 
 	srp_disconnect_target(target);
 	/*

@@ -726,8 +804,7 @@ static int srp_reconnect_target(struct srp_target_port *target)
 
 	for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
 		struct srp_request *req = &target->req_ring[i];
-		if (req->scmnd)
-			srp_reset_req(target, req);
+		srp_finish_req(target, req, DID_RESET << 16);
 	}
 
 	INIT_LIST_HEAD(&target->free_tx);

@@ -737,28 +814,9 @@ static int srp_reconnect_target(struct srp_target_port *target)
 	if (ret == 0)
 		ret = srp_connect_target(target);
 
-	scsi_target_unblock(&shost->shost_gendev, ret == 0 ? SDEV_RUNNING :
-			    SDEV_TRANSPORT_OFFLINE);
-	target->transport_offline = !!ret;
-
-	if (ret)
-		goto err;
-
-	shost_printk(KERN_INFO, target->scsi_host, PFX "reconnect succeeded\n");
-
-	return ret;
-
-err:
-	shost_printk(KERN_ERR, target->scsi_host,
-		     PFX "reconnect failed (%d), removing target port.\n", ret);
-
-	/*
-	 * We couldn't reconnect, so kill our target port off.
-	 * However, we have to defer the real removal because we
-	 * are in the context of the SCSI error handler now, which
-	 * will deadlock if we call scsi_remove_host().
-	 */
-	srp_queue_remove_work(target);
+	if (ret == 0)
+		shost_printk(KERN_INFO, target->scsi_host,
+			     PFX "reconnect succeeded\n");
 
 	return ret;
 }

@@ -1356,10 +1414,11 @@ static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
 	struct srp_cmd *cmd;
 	struct ib_device *dev;
 	unsigned long flags;
-	int len;
+	int len, result;
 
-	if (unlikely(target->transport_offline)) {
-		scmnd->result = DID_NO_CONNECT << 16;
+	result = srp_chkready(target->rport);
+	if (unlikely(result)) {
+		scmnd->result = result;
 		scmnd->scsi_done(scmnd);
 		return 0;
 	}

@@ -1757,7 +1816,7 @@ static int srp_abort(struct scsi_cmnd *scmnd)
 	if (srp_send_tsk_mgmt(target, req->index, scmnd->device->lun,
 			      SRP_TSK_ABORT_TASK) == 0)
 		ret = SUCCESS;
-	else if (target->transport_offline)
+	else if (target->rport->state == SRP_RPORT_LOST)
 		ret = FAST_IO_FAIL;
 	else
 		ret = FAILED;

@@ -1784,7 +1843,7 @@ static int srp_reset_device(struct scsi_cmnd *scmnd)
 	for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
 		struct srp_request *req = &target->req_ring[i];
 		if (req->scmnd && req->scmnd->device == scmnd->device)
-			srp_reset_req(target, req);
+			srp_finish_req(target, req, DID_RESET << 16);
 	}
 
 	return SUCCESS;

@@ -1793,14 +1852,10 @@ static int srp_reset_device(struct scsi_cmnd *scmnd)
 static int srp_reset_host(struct scsi_cmnd *scmnd)
 {
 	struct srp_target_port *target = host_to_target(scmnd->device->host);
-	int ret = FAILED;
 
 	shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
 
-	if (!srp_reconnect_target(target))
-		ret = SUCCESS;
-
-	return ret;
+	return srp_reconnect_rport(target->rport) == 0 ? SUCCESS : FAILED;
 }
 
 static int srp_slave_configure(struct scsi_device *sdev)

@@ -2637,7 +2692,13 @@ static void srp_remove_one(struct ib_device *device)
 }
 
 static struct srp_function_template ib_srp_transport_functions = {
+	.has_rport_state	 = true,
+	.reset_timer_if_blocked	 = true,
+	.fast_io_fail_tmo	 = &srp_fast_io_fail_tmo,
+	.dev_loss_tmo		 = &srp_dev_loss_tmo,
+	.reconnect		 = srp_rport_reconnect,
 	.rport_delete		 = srp_rport_delete,
+	.terminate_rport_io	 = srp_terminate_io,
 };
 
 static int __init srp_init_module(void)

index 2a1768f..fd1817e 100644
@@ -140,7 +140,6 @@ struct srp_target_port {
 	unsigned int		cmd_sg_cnt;
 	unsigned int		indirect_size;
 	bool			allow_ext_sg;
-	bool			transport_offline;
 
 	/* Everything above this point is used in the hot path of
 	 * command processing. Try to keep them packed into cachelines.

index 5551f3b..ceb84b6 100644
@@ -593,6 +593,7 @@ static void srp_remove_target(struct srp_target_port *target)
 	srp_disconnect_target(target);
 	ib_destroy_cm_id(target->cm_id);
 	srp_free_target_ib(target);
+	cancel_work_sync(&target->tl_err_work);
 	srp_rport_put(target->rport);
 	srp_free_req_data(target);
 

@@ -1363,6 +1364,21 @@ static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
 			     PFX "Recv failed with error code %d\n", res);
 }
 
+/**
+ * srp_tl_err_work() - handle a transport layer error
+ *
+ * Note: This function may get invoked before the rport has been created,
+ * hence the target->rport test.
+ */
+static void srp_tl_err_work(struct work_struct *work)
+{
+	struct srp_target_port *target;
+
+	target = container_of(work, struct srp_target_port, tl_err_work);
+	if (target->rport)
+		srp_start_tl_fail_timers(target->rport);
+}
+
 static void srp_handle_qp_err(enum ib_wc_status wc_status, bool send_err,
 			      struct srp_target_port *target)
 {

@@ -1371,6 +1387,7 @@ static void srp_handle_qp_err(enum ib_wc_status wc_status, bool send_err,
 			     PFX "failed %s status %d\n",
 			     send_err ? "send" : "receive",
 			     wc_status);
+		queue_work(system_long_wq, &target->tl_err_work);
 	}
 	target->qp_in_error = true;
 }

@@ -1733,6 +1750,7 @@ static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
 		if (ib_send_cm_drep(cm_id, NULL, 0))
 			shost_printk(KERN_ERR, target->scsi_host,
 				     PFX "Sending CM DREP failed\n");
+		queue_work(system_long_wq, &target->tl_err_work);
 		break;
 
 	case IB_CM_TIMEWAIT_EXIT:

@@ -2419,6 +2437,7 @@ static ssize_t srp_create_target(struct device *dev,
 			     sizeof (struct srp_indirect_buf) +
 			     target->cmd_sg_cnt * sizeof (struct srp_direct_buf);
 
+	INIT_WORK(&target->tl_err_work, srp_tl_err_work);
 	INIT_WORK(&target->remove_work, srp_remove_work);
 	spin_lock_init(&target->lock);
 	INIT_LIST_HEAD(&target->free_tx);

index fd1817e..446b045 100644
@@ -177,6 +177,7 @@ struct srp_target_port {
 	struct srp_iu	       *rx_ring[SRP_RQ_SIZE];
 	struct srp_request	req_ring[SRP_CMD_SQ_SIZE];
 
+	struct work_struct	tl_err_work;
 	struct work_struct	remove_work;
 
 	struct list_head	list;

index 675e203..04a97b6 100644
@@ -41,7 +41,7 @@ struct srp_host_attrs {
 #define to_srp_host_attrs(host)	((struct srp_host_attrs *)(host)->shost_data)
 
 #define SRP_HOST_ATTRS 0
-#define SRP_RPORT_ATTRS 6
+#define SRP_RPORT_ATTRS 8
 
 struct srp_internal {
 	struct scsi_transport_template t;

@@ -69,11 +69,13 @@ static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r)
  * are finished in a reasonable time. Hence do not allow the fast I/O fail
  * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT. Furthermore, these
  * parameters must be such that multipath can detect failed paths timely.
- * Hence do not allow both parameters to be disabled simultaneously.
+ * Hence do not allow all three parameters to be disabled simultaneously.
  */
-int srp_tmo_valid(int fast_io_fail_tmo, int dev_loss_tmo)
+int srp_tmo_valid(int reconnect_delay, int fast_io_fail_tmo, int dev_loss_tmo)
 {
-	if (fast_io_fail_tmo < 0 && dev_loss_tmo < 0)
+	if (reconnect_delay < 0 && fast_io_fail_tmo < 0 && dev_loss_tmo < 0)
+		return -EINVAL;
+	if (reconnect_delay == 0)
 		return -EINVAL;
 	if (fast_io_fail_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
 		return -EINVAL;

@@ -202,6 +204,56 @@ static int srp_parse_tmo(int *tmo, const char *buf)
 	return res;
 }
 
+static ssize_t show_reconnect_delay(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct srp_rport *rport = transport_class_to_srp_rport(dev);
+
+	return srp_show_tmo(buf, rport->reconnect_delay);
+}
+
+static ssize_t store_reconnect_delay(struct device *dev,
+				     struct device_attribute *attr,
+				     const char *buf, const size_t count)
+{
+	struct srp_rport *rport = transport_class_to_srp_rport(dev);
+	int res, delay;
+
+	res = srp_parse_tmo(&delay, buf);
+	if (res)
+		goto out;
+	res = srp_tmo_valid(delay, rport->fast_io_fail_tmo,
+			    rport->dev_loss_tmo);
+	if (res)
+		goto out;
+
+	if (rport->reconnect_delay <= 0 && delay > 0 &&
+	    rport->state != SRP_RPORT_RUNNING) {
+		queue_delayed_work(system_long_wq, &rport->reconnect_work,
+				   delay * HZ);
+	} else if (delay <= 0) {
+		cancel_delayed_work(&rport->reconnect_work);
+	}
+	rport->reconnect_delay = delay;
+	res = count;
+
+out:
+	return res;
+}
+
+static DEVICE_ATTR(reconnect_delay, S_IRUGO | S_IWUSR, show_reconnect_delay,
+		   store_reconnect_delay);
+
+static ssize_t show_failed_reconnects(struct device *dev,
+				      struct device_attribute *attr, char *buf)
+{
+	struct srp_rport *rport = transport_class_to_srp_rport(dev);
+
+	return sprintf(buf, "%d\n", rport->failed_reconnects);
+}
+
+static DEVICE_ATTR(failed_reconnects, S_IRUGO, show_failed_reconnects, NULL);
+
 static ssize_t show_srp_rport_fast_io_fail_tmo(struct device *dev,
 					       struct device_attribute *attr,
 					       char *buf)

@@ -222,7 +274,8 @@ static ssize_t store_srp_rport_fast_io_fail_tmo(struct device *dev,
 	res = srp_parse_tmo(&fast_io_fail_tmo, buf);
 	if (res)
 		goto out;
-	res = srp_tmo_valid(fast_io_fail_tmo, rport->dev_loss_tmo);
+	res = srp_tmo_valid(rport->reconnect_delay, fast_io_fail_tmo,
+			    rport->dev_loss_tmo);
 	if (res)
 		goto out;
 	rport->fast_io_fail_tmo = fast_io_fail_tmo;

@@ -256,7 +309,8 @@ static ssize_t store_srp_rport_dev_loss_tmo(struct device *dev,
 	res = srp_parse_tmo(&dev_loss_tmo, buf);
 	if (res)
 		goto out;
-	res = srp_tmo_valid(rport->fast_io_fail_tmo, dev_loss_tmo);
+	res = srp_tmo_valid(rport->reconnect_delay, rport->fast_io_fail_tmo,
+			    dev_loss_tmo);
 	if (res)
 		goto out;
 	rport->dev_loss_tmo = dev_loss_tmo;

@@ -312,6 +366,29 @@ invalid:
 	return -EINVAL;
 }
 
+/**
+ * srp_reconnect_work() - reconnect and schedule a new attempt if necessary
+ */
+static void srp_reconnect_work(struct work_struct *work)
+{
+	struct srp_rport *rport = container_of(to_delayed_work(work),
+					struct srp_rport, reconnect_work);
+	struct Scsi_Host *shost = rport_to_shost(rport);
+	int delay, res;
+
+	res = srp_reconnect_rport(rport);
+	if (res != 0) {
+		shost_printk(KERN_ERR, shost,
+			     "reconnect attempt %d failed (%d)\n",
+			     ++rport->failed_reconnects, res);
+		delay = rport->reconnect_delay *
+			min(100, max(1, rport->failed_reconnects - 10));
+		if (delay > 0)
+			queue_delayed_work(system_long_wq,
+					   &rport->reconnect_work, delay * HZ);
+	}
+}
+
 static void __rport_fail_io_fast(struct srp_rport *rport)
 {
 	struct Scsi_Host *shost = rport_to_shost(rport);

@@ -370,16 +447,21 @@ static void rport_dev_loss_timedout(struct work_struct *work)
 static void __srp_start_tl_fail_timers(struct srp_rport *rport)
 {
 	struct Scsi_Host *shost = rport_to_shost(rport);
-	int fast_io_fail_tmo, dev_loss_tmo;
+	int delay, fast_io_fail_tmo, dev_loss_tmo;
 
 	lockdep_assert_held(&rport->mutex);
 
 	if (!rport->deleted) {
+		delay = rport->reconnect_delay;
 		fast_io_fail_tmo = rport->fast_io_fail_tmo;
 		dev_loss_tmo = rport->dev_loss_tmo;
 		pr_debug("%s current state: %d\n",
 			 dev_name(&shost->shost_gendev), rport->state);
 
+		if (delay > 0)
+			queue_delayed_work(system_long_wq,
+					   &rport->reconnect_work,
+					   1UL * delay * HZ);
 		if (fast_io_fail_tmo >= 0 &&
 		    srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) {
 			pr_debug("%s new state: %d\n",

@@ -480,6 +562,7 @@ int srp_reconnect_rport(struct srp_rport *rport)
 		cancel_delayed_work(&rport->fast_io_fail_work);
 		cancel_delayed_work(&rport->dev_loss_work);
 
+		rport->failed_reconnects = 0;
 		srp_rport_set_state(rport, SRP_RPORT_RUNNING);
 		scsi_target_unblock(&shost->shost_gendev, SDEV_RUNNING);
 		/*

@@ -538,6 +621,7 @@ static void srp_rport_release(struct device *dev)
 {
 	struct srp_rport *rport = dev_to_rport(dev);
 
+	cancel_delayed_work_sync(&rport->reconnect_work);
 	cancel_delayed_work_sync(&rport->fast_io_fail_work);
 	cancel_delayed_work_sync(&rport->dev_loss_work);
 

@@ -634,6 +718,10 @@ struct srp_rport *srp_rport_add(struct Scsi_Host *shost,
 	memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id));
 	rport->roles = ids->roles;
 
+	if (i->f->reconnect)
+		rport->reconnect_delay = i->f->reconnect_delay ?
+			*i->f->reconnect_delay : 10;
+	INIT_DELAYED_WORK(&rport->reconnect_work, srp_reconnect_work);
 	rport->fast_io_fail_tmo = i->f->fast_io_fail_tmo ?
 		*i->f->fast_io_fail_tmo : 15;
 	rport->dev_loss_tmo = i->f->dev_loss_tmo ? *i->f->dev_loss_tmo : 60;

@@ -772,6 +860,10 @@ srp_attach_transport(struct srp_function_template *ft)
 		i->rport_attrs[count++] = &dev_attr_fast_io_fail_tmo;
 		i->rport_attrs[count++] = &dev_attr_dev_loss_tmo;
 	}
+	if (ft->reconnect) {
+		i->rport_attrs[count++] = &dev_attr_reconnect_delay;
+		i->rport_attrs[count++] = &dev_attr_failed_reconnects;
+	}
 	if (ft->rport_delete)
 		i->rport_attrs[count++] = &dev_attr_delete;
 	i->rport_attrs[count++] = NULL;

index ee70016..4ebf691 100644
@@ -31,7 +31,8 @@ enum srp_rport_state {
 /**
  * struct srp_rport
  * @lld_data: LLD private data.
- * @mutex:    Protects against concurrent rport fast_io_fail / dev_loss_tmo.
+ * @mutex:    Protects against concurrent rport reconnect / fast_io_fail /
+ *   dev_loss_tmo activity.
  */
 struct srp_rport {
 	/* for initiator and target drivers */

@@ -48,6 +49,9 @@ struct srp_rport {
 	struct mutex		mutex;
 	enum srp_rport_state	state;
 	bool			deleted;
+	int			reconnect_delay;
+	int			failed_reconnects;
+	struct delayed_work	reconnect_work;
 	int			fast_io_fail_tmo;
 	int			dev_loss_tmo;
 	struct delayed_work	fast_io_fail_work;

@@ -60,6 +64,7 @@ struct srp_rport {
  *     dev_loss_tmo sysfs attribute for an rport.
  * @reset_timer_if_blocked: Whether or srp_timed_out() should reset the command
  *     timer if the device on which it has been queued is blocked.
+ * @reconnect_delay: If not NULL, points to the default reconnect_delay value.
  * @fast_io_fail_tmo: If not NULL, points to the default fast_io_fail_tmo value.
  * @dev_loss_tmo: If not NULL, points to the default dev_loss_tmo value.
  * @reconnect: Callback function for reconnecting to the target. See also

@@ -71,6 +76,7 @@ struct srp_function_template {
 	/* for initiator drivers */
 	bool has_rport_state;
 	bool reset_timer_if_blocked;
+	int *reconnect_delay;
 	int *fast_io_fail_tmo;
 	int *dev_loss_tmo;
 	int (*reconnect)(struct srp_rport *rport);

@@ -90,7 +96,8 @@ extern void srp_rport_put(struct srp_rport *rport);
 extern struct srp_rport *srp_rport_add(struct Scsi_Host *,
 				       struct srp_rport_identifiers *);
 extern void srp_rport_del(struct srp_rport *);
-extern int srp_tmo_valid(int fast_io_fail_tmo, int dev_loss_tmo);
+extern int srp_tmo_valid(int reconnect_delay, int fast_io_fail_tmo,
+			 int dev_loss_tmo);
 extern int srp_reconnect_rport(struct srp_rport *rport);
 extern void srp_start_tl_fail_timers(struct srp_rport *rport);
 extern void srp_remove_host(struct Scsi_Host *);

131 lines not on this page · raw message

index 4be3eb8..da60d11 100644
@@ -1965,6 +1965,14 @@ static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
 	return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
 }
 
+static ssize_t show_sgid(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct srp_target_port *target = host_to_target(class_to_shost(dev));
+
+	return sprintf(buf, "%pI6\n", target->path.sgid.raw);
+}
+
 static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
 			 char *buf)
 {

@@ -2049,6 +2057,7 @@ static DEVICE_ATTR(id_ext,	    S_IRUGO, show_id_ext,	   NULL);
 static DEVICE_ATTR(ioc_guid,	    S_IRUGO, show_ioc_guid,	   NULL);
 static DEVICE_ATTR(service_id,	    S_IRUGO, show_service_id,	   NULL);
 static DEVICE_ATTR(pkey,	    S_IRUGO, show_pkey,		   NULL);
+static DEVICE_ATTR(sgid,	    S_IRUGO, show_sgid,		   NULL);
 static DEVICE_ATTR(dgid,	    S_IRUGO, show_dgid,		   NULL);
 static DEVICE_ATTR(orig_dgid,	    S_IRUGO, show_orig_dgid,	   NULL);
 static DEVICE_ATTR(req_lim,         S_IRUGO, show_req_lim,         NULL);

@@ -2065,6 +2074,7 @@ static struct device_attribute *srp_host_attrs[] = {
 	&dev_attr_ioc_guid,
 	&dev_attr_service_id,
 	&dev_attr_pkey,
+	&dev_attr_sgid,
 	&dev_attr_dgid,
 	&dev_attr_orig_dgid,
 	&dev_attr_req_lim,

index da60d11..fdc0bc1 100644
@@ -576,6 +576,42 @@ static void srp_free_req_data(struct srp_target_port *target)
 	}
 }
 
+static int srp_alloc_req_data(struct srp_target_port *target)
+{
+	struct srp_device *srp_dev = target->srp_host->srp_dev;
+	struct ib_device *ibdev = srp_dev->dev;
+	struct srp_request *req;
+	dma_addr_t dma_addr;
+	int i, ret = -ENOMEM;
+
+	INIT_LIST_HEAD(&target->free_reqs);
+
+	for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
+		req = &target->req_ring[i];
+		req->fmr_list = kmalloc(target->cmd_sg_cnt * sizeof(void *),
+					GFP_KERNEL);
+		req->map_page = kmalloc(SRP_FMR_SIZE * sizeof(void *),
+					GFP_KERNEL);
+		req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
+		if (!req->fmr_list || !req->map_page || !req->indirect_desc)
+			goto out;
+
+		dma_addr = ib_dma_map_single(ibdev, req->indirect_desc,
+					     target->indirect_size,
+					     DMA_TO_DEVICE);
+		if (ib_dma_mapping_error(ibdev, dma_addr))
+			goto out;
+
+		req->indirect_dma_addr = dma_addr;
+		req->index = i;
+		list_add_tail(&req->list, &target->free_reqs);
+	}
+	ret = 0;
+
+out:
+	return ret;
+}
+
 /**
  * srp_del_scsi_host_attr() - Remove attributes defined in the host template.
  * @shost: SCSI host whose attributes to remove from sysfs.

@@ -2433,8 +2469,7 @@ static ssize_t srp_create_target(struct device *dev,
 	struct Scsi_Host *target_host;
 	struct srp_target_port *target;
 	struct ib_device *ibdev = host->srp_dev->dev;
-	dma_addr_t dma_addr;
-	int i, ret;
+	int ret;
 
 	target_host = scsi_host_alloc(&srp_template,
 				      sizeof (struct srp_target_port));

@@ -2490,28 +2525,9 @@ static ssize_t srp_create_target(struct device *dev,
 	INIT_WORK(&target->remove_work, srp_remove_work);
 	spin_lock_init(&target->lock);
 	INIT_LIST_HEAD(&target->free_tx);
-	INIT_LIST_HEAD(&target->free_reqs);
-	for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
-		struct srp_request *req = &target->req_ring[i];
-
-		req->fmr_list = kmalloc(target->cmd_sg_cnt * sizeof (void *),
-					GFP_KERNEL);
-		req->map_page = kmalloc(SRP_FMR_SIZE * sizeof (void *),
-					GFP_KERNEL);
-		req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
-		if (!req->fmr_list || !req->map_page || !req->indirect_desc)
-			goto err_free_mem;
-
-		dma_addr = ib_dma_map_single(ibdev, req->indirect_desc,
-					     target->indirect_size,
-					     DMA_TO_DEVICE);
-		if (ib_dma_mapping_error(ibdev, dma_addr))
-			goto err_free_mem;
-
-		req->indirect_dma_addr = dma_addr;
-		req->index = i;
-		list_add_tail(&req->list, &target->free_reqs);
-	}
+	ret = srp_alloc_req_data(target);
+	if (ret)
+		goto err_free_mem;
 
 	ib_query_gid(ibdev, host->port, 0, &target->path.sgid);
 

index fdc0bc1..b0a37ff 100644
@@ -299,16 +299,16 @@ static int srp_create_target_ib(struct srp_target_port *target)
 		return -ENOMEM;
 
 	recv_cq = ib_create_cq(target->srp_host->srp_dev->dev,
-			       srp_recv_completion, NULL, target, SRP_RQ_SIZE,
-			       target->comp_vector);
+			       srp_recv_completion, NULL, target,
+			       target->queue_size, target->comp_vector);
 	if (IS_ERR(recv_cq)) {
 		ret = PTR_ERR(recv_cq);
 		goto err;
 	}
 
 	send_cq = ib_create_cq(target->srp_host->srp_dev->dev,
-			       srp_send_completion, NULL, target, SRP_SQ_SIZE,
-			       target->comp_vector);
+			       srp_send_completion, NULL, target,
+			       target->queue_size, target->comp_vector);
 	if (IS_ERR(send_cq)) {
 		ret = PTR_ERR(send_cq);
 		goto err_recv_cq;

@@ -317,8 +317,8 @@ static int srp_create_target_ib(struct srp_target_port *target)
 	ib_req_notify_cq(recv_cq, IB_CQ_NEXT_COMP);
 
 	init_attr->event_handler       = srp_qp_event;
-	init_attr->cap.max_send_wr     = SRP_SQ_SIZE;
-	init_attr->cap.max_recv_wr     = SRP_RQ_SIZE;
+	init_attr->cap.max_send_wr     = target->queue_size;
+	init_attr->cap.max_recv_wr     = target->queue_size;
 	init_attr->cap.max_recv_sge    = 1;
 	init_attr->cap.max_send_sge    = 1;
 	init_attr->sq_sig_type         = IB_SIGNAL_ALL_WR;

@@ -364,6 +364,10 @@ err:
 	return ret;
 }
 
+/*
+ * Note: this function may be called without srp_alloc_iu_bufs() having been
+ * invoked. Hence the target->[rt]x_ring checks.
+ */
 static void srp_free_target_ib(struct srp_target_port *target)
 {
 	int i;

@@ -375,10 +379,18 @@ static void srp_free_target_ib(struct srp_target_port *target)
 	target->qp = NULL;
 	target->send_cq = target->recv_cq = NULL;
 
-	for (i = 0; i < SRP_RQ_SIZE; ++i)
-		srp_free_iu(target->srp_host, target->rx_ring[i]);
-	for (i = 0; i < SRP_SQ_SIZE; ++i)
-		srp_free_iu(target->srp_host, target->tx_ring[i]);
+	if (target->rx_ring) {
+		for (i = 0; i < target->queue_size; ++i)
+			srp_free_iu(target->srp_host, target->rx_ring[i]);
+		kfree(target->rx_ring);
+		target->rx_ring = NULL;
+	}
+	if (target->tx_ring) {
+		for (i = 0; i < target->queue_size; ++i)
+			srp_free_iu(target->srp_host, target->tx_ring[i]);
+		kfree(target->tx_ring);
+		target->tx_ring = NULL;
+	}
 }
 
 static void srp_path_rec_completion(int status,

@@ -564,7 +576,11 @@ static void srp_free_req_data(struct srp_target_port *target)
 	struct srp_request *req;
 	int i;
 
-	for (i = 0, req = target->req_ring; i < SRP_CMD_SQ_SIZE; ++i, ++req) {
+	if (!target->req_ring)
+		return;
+
+	for (i = 0; i < target->req_ring_size; ++i) {
+		req = &target->req_ring[i];
 		kfree(req->fmr_list);
 		kfree(req->map_page);
 		if (req->indirect_dma_addr) {

@@ -574,6 +590,9 @@ static void srp_free_req_data(struct srp_target_port *target)
 		}
 		kfree(req->indirect_desc);
 	}
+
+	kfree(target->req_ring);
+	target->req_ring = NULL;
 }
 
 static int srp_alloc_req_data(struct srp_target_port *target)

@@ -586,7 +605,12 @@ static int srp_alloc_req_data(struct srp_target_port *target)
 
 	INIT_LIST_HEAD(&target->free_reqs);
 
-	for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
+	target->req_ring = kzalloc(target->req_ring_size *
+				   sizeof(*target->req_ring), GFP_KERNEL);
+	if (!target->req_ring)
+		goto out;
+
+	for (i = 0; i < target->req_ring_size; ++i) {
 		req = &target->req_ring[i];
 		req->fmr_list = kmalloc(target->cmd_sg_cnt * sizeof(void *),
 					GFP_KERNEL);

@@ -811,7 +835,7 @@ static void srp_terminate_io(struct srp_rport *rport)
 	struct srp_target_port *target = rport->lld_data;
 	int i;
 
-	for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
+	for (i = 0; i < target->req_ring_size; ++i) {
 		struct srp_request *req = &target->req_ring[i];
 		srp_finish_req(target, req, DID_TRANSPORT_FAILFAST << 16);
 	}

@@ -848,13 +872,13 @@ static int srp_rport_reconnect(struct srp_rport *rport)
 	else
 		srp_create_target_ib(target);
 
-	for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
+	for (i = 0; i < target->req_ring_size; ++i) {
 		struct srp_request *req = &target->req_ring[i];
 		srp_finish_req(target, req, DID_RESET << 16);
 	}
 
 	INIT_LIST_HEAD(&target->free_tx);
-	for (i = 0; i < SRP_SQ_SIZE; ++i)
+	for (i = 0; i < target->queue_size; ++i)
 		list_add(&target->tx_ring[i]->list, &target->free_tx);
 
 	if (ret == 0)

@@ -1562,11 +1586,24 @@ err_unlock:
 	return SCSI_MLQUEUE_HOST_BUSY;
 }
 
+/*
+ * Note: the resources allocated in this function are freed in
+ * srp_free_target_ib().
+ */
 static int srp_alloc_iu_bufs(struct srp_target_port *target)
 {
 	int i;
 
-	for (i = 0; i < SRP_RQ_SIZE; ++i) {
+	target->rx_ring = kzalloc(target->queue_size * sizeof(*target->rx_ring),
+				  GFP_KERNEL);
+	if (!target->rx_ring)
+		goto err_no_ring;
+	target->tx_ring = kzalloc(target->queue_size * sizeof(*target->tx_ring),
+				  GFP_KERNEL);
+	if (!target->tx_ring)
+		goto err_no_ring;
+
+	for (i = 0; i < target->queue_size; ++i) {
 		target->rx_ring[i] = srp_alloc_iu(target->srp_host,
 						  target->max_ti_iu_len,
 						  GFP_KERNEL, DMA_FROM_DEVICE);

@@ -1574,7 +1611,7 @@ static int srp_alloc_iu_bufs(struct srp_target_port *target)
 			goto err;
 	}
 
-	for (i = 0; i < SRP_SQ_SIZE; ++i) {
+	for (i = 0; i < target->queue_size; ++i) {
 		target->tx_ring[i] = srp_alloc_iu(target->srp_host,
 						  target->max_iu_len,
 						  GFP_KERNEL, DMA_TO_DEVICE);

@@ -1587,16 +1624,18 @@ static int srp_alloc_iu_bufs(struct srp_target_port *target)
 	return 0;
 
 err:
-	for (i = 0; i < SRP_RQ_SIZE; ++i) {
+	for (i = 0; i < target->queue_size; ++i) {
 		srp_free_iu(target->srp_host, target->rx_ring[i]);
-		target->rx_ring[i] = NULL;
-	}
-
-	for (i = 0; i < SRP_SQ_SIZE; ++i) {
 		srp_free_iu(target->srp_host, target->tx_ring[i]);
-		target->tx_ring[i] = NULL;
 	}
 
+
+err_no_ring:
+	kfree(target->tx_ring);
+	target->tx_ring = NULL;
+	kfree(target->rx_ring);
+	target->rx_ring = NULL;
+
 	return -ENOMEM;
 }
 

@@ -1647,6 +1686,9 @@ static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
 		target->scsi_host->can_queue
 			= min(target->req_lim - SRP_TSK_MGMT_SQ_SIZE,
 			      target->scsi_host->can_queue);
+		target->scsi_host->cmd_per_lun
+			= min_t(int, target->scsi_host->can_queue,
+				target->scsi_host->cmd_per_lun);
 	} else {
 		shost_printk(KERN_WARNING, target->scsi_host,
 			     PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);

@@ -1654,7 +1696,7 @@ static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
 		goto error;
 	}
 
-	if (!target->rx_ring[0]) {
+	if (!target->rx_ring) {
 		ret = srp_alloc_iu_bufs(target);
 		if (ret)
 			goto error;

@@ -1674,7 +1716,7 @@ static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
 	if (ret)
 		goto error_free;
 
-	for (i = 0; i < SRP_RQ_SIZE; i++) {
+	for (i = 0; i < target->queue_size; i++) {
 		struct srp_iu *iu = target->rx_ring[i];
 		ret = srp_post_recv(target, iu);
 		if (ret)

@@ -1933,7 +1975,7 @@ static int srp_reset_device(struct scsi_cmnd *scmnd)
 	if (target->tsk_mgmt_status)
 		return FAILED;
 
-	for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
+	for (i = 0; i < target->req_ring_size; ++i) {
 		struct srp_request *req = &target->req_ring[i];
 		if (req->scmnd && req->scmnd->device == scmnd->device)
 			srp_finish_req(target, req, DID_RESET << 16);

@@ -2136,9 +2178,9 @@ static struct scsi_host_template srp_template = {
 	.eh_host_reset_handler		= srp_reset_host,
 	.skip_settle_delay		= true,
 	.sg_tablesize			= SRP_DEF_SG_TABLESIZE,
-	.can_queue			= SRP_CMD_SQ_SIZE,
+	.can_queue			= SRP_DEFAULT_CMD_SQ_SIZE,
 	.this_id			= -1,
-	.cmd_per_lun			= SRP_CMD_SQ_SIZE,
+	.cmd_per_lun			= SRP_DEFAULT_CMD_SQ_SIZE,
 	.use_clustering			= ENABLE_CLUSTERING,
 	.shost_attrs			= srp_host_attrs
 };

@@ -2245,6 +2287,7 @@ enum {
 	SRP_OPT_SG_TABLESIZE	= 1 << 11,
 	SRP_OPT_COMP_VECTOR	= 1 << 12,
 	SRP_OPT_TL_RETRY_COUNT	= 1 << 13,
+	SRP_OPT_CAN_QUEUE	= 1 << 14,
 	SRP_OPT_ALL		= (SRP_OPT_ID_EXT	|
 				   SRP_OPT_IOC_GUID	|
 				   SRP_OPT_DGID		|

@@ -2267,6 +2310,7 @@ static const match_table_t srp_opt_tokens = {
 	{ SRP_OPT_SG_TABLESIZE,		"sg_tablesize=%u"	},
 	{ SRP_OPT_COMP_VECTOR,		"comp_vector=%u"	},
 	{ SRP_OPT_TL_RETRY_COUNT,	"tl_retry_count=%u"	},
+	{ SRP_OPT_CAN_QUEUE,		"can_queue=%d"		},
 	{ SRP_OPT_ERR,			NULL 			}
 };
 

@@ -2361,13 +2405,25 @@ static int srp_parse_options(const char *buf, struct srp_target_port *target)
 			target->scsi_host->max_sectors = token;
 			break;
 
+		case SRP_OPT_CAN_QUEUE:
+			if (match_int(args, &token) || token < 1) {
+				pr_warn("bad can_queue parameter '%s'\n", p);
+				goto out;
+			}
+			target->scsi_host->can_queue = token;
+			target->queue_size = token + SRP_RSP_SQ_SIZE +
+					     SRP_TSK_MGMT_SQ_SIZE;
+			if (!(opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
+				target->scsi_host->cmd_per_lun = token;
+			break;
+
 		case SRP_OPT_MAX_CMD_PER_LUN:
-			if (match_int(args, &token)) {
+			if (match_int(args, &token) || token < 1) {
 				pr_warn("bad max cmd_per_lun parameter '%s'\n",
 					p);
 				goto out;
 			}
-			target->scsi_host->cmd_per_lun = min(token, SRP_CMD_SQ_SIZE);
+			target->scsi_host->cmd_per_lun = token;
 			break;
 
 		case SRP_OPT_IO_CLASS:

@@ -2455,6 +2511,12 @@ static int srp_parse_options(const char *buf, struct srp_target_port *target)
 				pr_warn("target creation request is missing parameter '%s'\n",
 					srp_opt_tokens[i].pattern);
 
+	if (target->scsi_host->cmd_per_lun > target->scsi_host->can_queue
+	    && (opt_mask & SRP_OPT_MAX_CMD_PER_LUN))
+		pr_warn("cmd_per_lun = %d > can_queue = %d\n",
+			target->scsi_host->cmd_per_lun,
+			target->scsi_host->can_queue);
+
 out:
 	kfree(options);
 	return ret;

@@ -2493,11 +2555,14 @@ static ssize_t srp_create_target(struct device *dev,
 	target->sg_tablesize	= indirect_sg_entries ? : cmd_sg_entries;
 	target->allow_ext_sg	= allow_ext_sg;
 	target->tl_retry_count	= 7;
+	target->queue_size	= SRP_DEFAULT_QUEUE_SIZE;
 
 	ret = srp_parse_options(buf, target);
 	if (ret)
 		goto err;
 
+	target->req_ring_size = target->queue_size - SRP_TSK_MGMT_SQ_SIZE;
+
 	if (!srp_conn_unique(target->srp_host, target)) {
 		shost_printk(KERN_INFO, target->scsi_host,
 			     PFX "Already connected to target port with id_ext=%016llx;ioc_guid=%016llx;initiator_ext=%016llx\n",

index 446b045..5756810 100644
@@ -57,14 +57,11 @@ enum {
 	SRP_MAX_LUN		= 512,
 	SRP_DEF_SG_TABLESIZE	= 12,
 
-	SRP_RQ_SHIFT    	= 6,
-	SRP_RQ_SIZE		= 1 << SRP_RQ_SHIFT,
-
-	SRP_SQ_SIZE		= SRP_RQ_SIZE,
+	SRP_DEFAULT_QUEUE_SIZE	= 1 << 6,
 	SRP_RSP_SQ_SIZE		= 1,
-	SRP_REQ_SQ_SIZE		= SRP_SQ_SIZE - SRP_RSP_SQ_SIZE,
 	SRP_TSK_MGMT_SQ_SIZE	= 1,
-	SRP_CMD_SQ_SIZE		= SRP_REQ_SQ_SIZE - SRP_TSK_MGMT_SQ_SIZE,
+	SRP_DEFAULT_CMD_SQ_SIZE = SRP_DEFAULT_QUEUE_SIZE - SRP_RSP_SQ_SIZE -
+				  SRP_TSK_MGMT_SQ_SIZE,
 
 	SRP_TAG_NO_REQ		= ~0U,
 	SRP_TAG_TSK_MGMT	= 1U << 31,

@@ -156,6 +153,8 @@ struct srp_target_port {
 	char			target_name[32];
 	unsigned int		scsi_id;
 	unsigned int		sg_tablesize;
+	int			queue_size;
+	int			req_ring_size;
 	int			comp_vector;
 	int			tl_retry_count;
 

@@ -173,9 +172,9 @@ struct srp_target_port {
 
 	int			zero_req_lim;
 
-	struct srp_iu	       *tx_ring[SRP_SQ_SIZE];
-	struct srp_iu	       *rx_ring[SRP_RQ_SIZE];
-	struct srp_request	req_ring[SRP_CMD_SQ_SIZE];
+	struct srp_iu	       **tx_ring;
+	struct srp_iu	       **rx_ring;
+	struct srp_request	*req_ring;
 
 	struct work_struct	tl_err_work;
 	struct work_struct	remove_work;

index aed5b75..414fd02 100644
@@ -528,11 +528,13 @@ static void srp_remove_target(struct srp_target_port *target)
 	WARN_ON_ONCE(target->state != SRP_TARGET_REMOVED);
 
 	srp_del_scsi_host_attr(target->scsi_host);
+	srp_rport_get(target->rport);
 	srp_remove_host(target->scsi_host);
 	scsi_remove_host(target->scsi_host);
 	srp_disconnect_target(target);
 	ib_destroy_cm_id(target->cm_id);
 	srp_free_target_ib(target);
+	srp_rport_put(target->rport);
 	srp_free_req_data(target);
 
 	spin_lock(&target->srp_host->target_lock);

@@ -2004,6 +2006,7 @@ static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
 	}
 
 	rport->lld_data = target;
+	target->rport = rport;
 
 	spin_lock(&host->target_lock);
 	list_add_tail(&target->list, &host->target_list);

index 84d821b..2a1768f 100644
@@ -153,6 +153,7 @@ struct srp_target_port {
 	u16			io_class;
 	struct srp_host	       *srp_host;
 	struct Scsi_Host       *scsi_host;
+	struct srp_rport       *rport;
 	char			target_name[32];
 	unsigned int		scsi_id;
 	unsigned int		sg_tablesize;

index f379c7f..f7ba94a 100644
@@ -185,6 +185,24 @@ static int srp_host_match(struct attribute_container *cont, struct device *dev)
 }
 
 /**
+ * srp_rport_get() - increment rport reference count
+ */
+void srp_rport_get(struct srp_rport *rport)
+{
+	get_device(&rport->dev);
+}
+EXPORT_SYMBOL(srp_rport_get);
+
+/**
+ * srp_rport_put() - decrement rport reference count
+ */
+void srp_rport_put(struct srp_rport *rport)
+{
+	put_device(&rport->dev);
+}
+EXPORT_SYMBOL(srp_rport_put);
+
+/**
  * srp_rport_add - add a SRP remote port to the device hierarchy
  * @shost:	scsi host the remote port is connected to.
  * @ids:	The port id for the remote port.

index ff0f04a..5a2d2d1 100644
@@ -38,6 +38,8 @@ extern struct scsi_transport_template *
 srp_attach_transport(struct srp_function_template *);
 extern void srp_release_transport(struct scsi_transport_template *);
 
+extern void srp_rport_get(struct srp_rport *rport);
+extern void srp_rport_put(struct srp_rport *rport);
 extern struct srp_rport *srp_rport_add(struct Scsi_Host *,
 				       struct srp_rport_identifiers *);
 extern void srp_rport_del(struct srp_rport *);