nvme_fc: Support ctrl_loss_tmo

Sync with Sagi's recent addition of ctrl_loss_tmo in the core fabrics
layer.

Remove local connect limits and connect_attempts variable.
Use fabrics new nr_connects variable and use of nvmf_should_reconnect()
Refactor duplicate reconnect failure code.

Addresses review comment by Sagi on controller reset support:
http://lists.infradead.org/pipermail/linux-nvme/2017-April/009261.html

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/fc.c

@@ -45,8 +45,6 @@ enum nvme_fc_queue_flags {
 
 #define NVMEFC_QUEUE_DELAY	3		/* ms units */
 
-#define NVME_FC_MAX_CONNECT_ATTEMPTS	1
-
 struct nvme_fc_queue {
 	struct nvme_fc_ctrl	*ctrl;
 	struct device		*dev;
@@ -165,7 +163,6 @@ struct nvme_fc_ctrl {
 	struct work_struct	delete_work;
 	struct work_struct	reset_work;
 	struct delayed_work	connect_work;
-	int			connect_attempts;
 
 	struct kref		ref;
 	u32			flags;
@@ -2305,7 +2302,7 @@ nvme_fc_create_association(struct nvme_fc_ctrl *ctrl)
 	int ret;
 	bool changed;
 
-	ctrl->connect_attempts++;
+	++ctrl->ctrl.opts->nr_reconnects;
 
 	/*
 	 * Create the admin queue
@@ -2402,7 +2399,7 @@ nvme_fc_create_association(struct nvme_fc_ctrl *ctrl)
 	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
 	WARN_ON_ONCE(!changed);
 
-	ctrl->connect_attempts = 0;
+	ctrl->ctrl.opts->nr_reconnects = 0;
 
 	kref_get(&ctrl->ctrl.kref);
 
@@ -2545,16 +2542,22 @@ nvme_fc_delete_ctrl_work(struct work_struct *work)
 	nvme_put_ctrl(&ctrl->ctrl);
 }
 
+static bool
+__nvme_fc_schedule_delete_work(struct nvme_fc_ctrl *ctrl)
+{
+	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING))
+		return true;
+
+	if (!queue_work(nvme_fc_wq, &ctrl->delete_work))
+		return true;
+
+	return false;
+}
+
 static int
 __nvme_fc_del_ctrl(struct nvme_fc_ctrl *ctrl)
 {
-	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING))
+	return __nvme_fc_schedule_delete_work(ctrl) ? -EBUSY : 0;
-		return -EBUSY;
-
-	if (!queue_work(nvme_fc_wq, &ctrl->delete_work))
-		return -EBUSY;
-
-	return 0;
 }
 
 /*
@@ -2579,6 +2582,35 @@ nvme_fc_del_nvme_ctrl(struct nvme_ctrl *nctrl)
 	return ret;
 }
 
+static void
+nvme_fc_reconnect_or_delete(struct nvme_fc_ctrl *ctrl, int status)
+{
+	/* If we are resetting/deleting then do nothing */
+	if (ctrl->ctrl.state != NVME_CTRL_RECONNECTING) {
+		WARN_ON_ONCE(ctrl->ctrl.state == NVME_CTRL_NEW ||
+			ctrl->ctrl.state == NVME_CTRL_LIVE);
+		return;
+	}
+
+	dev_warn(ctrl->ctrl.device,
+		"NVME-FC{%d}: reset: Reconnect attempt failed (%d)\n",
+		ctrl->cnum, status);
+
+	if (nvmf_should_reconnect(&ctrl->ctrl)) {
+		dev_info(ctrl->ctrl.device,
+			"NVME-FC{%d}: Reconnect attempt in %d seconds.\n",
+			ctrl->cnum, ctrl->ctrl.opts->reconnect_delay);
+		queue_delayed_work(nvme_fc_wq, &ctrl->connect_work,
+				ctrl->ctrl.opts->reconnect_delay * HZ);
+	} else {
+		dev_info(ctrl->ctrl.device,
+				"NVME-FC{%d}: Max reconnect attempts (%d) "
+				"reached. Removing controller\n",
+				ctrl->cnum, ctrl->ctrl.opts->nr_reconnects);
+		WARN_ON(__nvme_fc_schedule_delete_work(ctrl));
+	}
+}
+
 static void
 nvme_fc_reset_ctrl_work(struct work_struct *work)
 {
@@ -2590,34 +2622,9 @@ nvme_fc_reset_ctrl_work(struct work_struct *work)
 	nvme_fc_delete_association(ctrl);
 
 	ret = nvme_fc_create_association(ctrl);
-	if (ret) {
+	if (ret)
-		dev_warn(ctrl->ctrl.device,
+		nvme_fc_reconnect_or_delete(ctrl, ret);
-			"NVME-FC{%d}: reset: Reconnect attempt failed (%d)\n",
+	else
-			ctrl->cnum, ret);
-		if (ctrl->connect_attempts >= NVME_FC_MAX_CONNECT_ATTEMPTS) {
-			dev_warn(ctrl->ctrl.device,
-				"NVME-FC{%d}: Max reconnect attempts (%d) "
-				"reached. Removing controller\n",
-				ctrl->cnum, ctrl->connect_attempts);
-
-			if (!nvme_change_ctrl_state(&ctrl->ctrl,
-				NVME_CTRL_DELETING)) {
-				dev_err(ctrl->ctrl.device,
-					"NVME-FC{%d}: failed to change state "
-					"to DELETING\n", ctrl->cnum);
-				return;
-			}
-
-			WARN_ON(!queue_work(nvme_fc_wq, &ctrl->delete_work));
-			return;
-		}
-
-		dev_warn(ctrl->ctrl.device,
-			"NVME-FC{%d}: Reconnect attempt in %d seconds.\n",
-			ctrl->cnum, ctrl->ctrl.opts->reconnect_delay);
-		queue_delayed_work(nvme_fc_wq, &ctrl->connect_work,
-				ctrl->ctrl.opts->reconnect_delay * HZ);
-	} else
 		dev_info(ctrl->ctrl.device,
 			"NVME-FC{%d}: controller reset complete\n", ctrl->cnum);
 }
@@ -2670,34 +2677,9 @@ nvme_fc_connect_ctrl_work(struct work_struct *work)
 				struct nvme_fc_ctrl, connect_work);
 
 	ret = nvme_fc_create_association(ctrl);
-	if (ret) {
+	if (ret)
-		dev_warn(ctrl->ctrl.device,
+		nvme_fc_reconnect_or_delete(ctrl, ret);
-			"NVME-FC{%d}: Reconnect attempt failed (%d)\n",
+	else
-			ctrl->cnum, ret);
-		if (ctrl->connect_attempts >= NVME_FC_MAX_CONNECT_ATTEMPTS) {
-			dev_warn(ctrl->ctrl.device,
-				"NVME-FC{%d}: Max reconnect attempts (%d) "
-				"reached. Removing controller\n",
-				ctrl->cnum, ctrl->connect_attempts);
-
-			if (!nvme_change_ctrl_state(&ctrl->ctrl,
-				NVME_CTRL_DELETING)) {
-				dev_err(ctrl->ctrl.device,
-					"NVME-FC{%d}: failed to change state "
-					"to DELETING\n", ctrl->cnum);
-				return;
-			}
-
-			WARN_ON(!queue_work(nvme_fc_wq, &ctrl->delete_work));
-			return;
-		}
-
-		dev_warn(ctrl->ctrl.device,
-			"NVME-FC{%d}: Reconnect attempt in %d seconds.\n",
-			ctrl->cnum, ctrl->ctrl.opts->reconnect_delay);
-		queue_delayed_work(nvme_fc_wq, &ctrl->connect_work,
-				ctrl->ctrl.opts->reconnect_delay * HZ);
-	} else
 		dev_info(ctrl->ctrl.device,
 			"NVME-FC{%d}: controller reconnect complete\n",
 			ctrl->cnum);
@@ -2969,7 +2951,7 @@ nvme_fc_create_ctrl(struct device *dev, struct nvmf_ctrl_options *opts)
 static struct nvmf_transport_ops nvme_fc_transport = {
 	.name		= "fc",
 	.required_opts	= NVMF_OPT_TRADDR | NVMF_OPT_HOST_TRADDR,
-	.allowed_opts	= NVMF_OPT_RECONNECT_DELAY,
+	.allowed_opts	= NVMF_OPT_RECONNECT_DELAY | NVMF_OPT_CTRL_LOSS_TMO,
 	.create_ctrl	= nvme_fc_create_ctrl,
 };