nvme: split nvme_uninit_ctrl into stop and uninit

Usually before we teardown the controller we want to:
1. complete/cancel any ctrl inflight works
2. remove ctrl namespaces (only for removal though, resets
   shouldn't remove any namespaces).

but we do not want to destroy the controller device as
we might use it for logging during the teardown stage.

This patch adds nvme_start_ctrl() which queues inflight
controller works (aen, ns scan, queue start and keep-alive
if kato is set) and nvme_stop_ctrl() which cancels the works
namespace removal is left to the callers to handle.

Move nvme_uninit_ctrl after we are done with the
controller device.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
index 8d55e78..d666ada 100644
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -2232,7 +2232,6 @@
 out_delete_hw_queues:
 	nvme_fc_delete_hw_io_queues(ctrl);
 out_cleanup_blk_queue:
-	nvme_stop_keep_alive(&ctrl->ctrl);
 	blk_cleanup_queue(ctrl->ctrl.connect_q);
 out_free_tag_set:
 	blk_mq_free_tag_set(&ctrl->tag_set);
@@ -2366,8 +2365,6 @@
 		goto out_disconnect_admin_queue;
 	}
 
-	nvme_start_keep_alive(&ctrl->ctrl);
-
 	/* FC-NVME supports normal SGL Data Block Descriptors */
 
 	if (opts->queue_size > ctrl->ctrl.maxcmd) {
@@ -2401,17 +2398,12 @@
 
 	ctrl->ctrl.nr_reconnects = 0;
 
-	if (ctrl->ctrl.queue_count > 1) {
-		nvme_start_queues(&ctrl->ctrl);
-		nvme_queue_scan(&ctrl->ctrl);
-		nvme_queue_async_events(&ctrl->ctrl);
-	}
+	nvme_start_ctrl(&ctrl->ctrl);
 
 	return 0;	/* Success */
 
 out_term_aen_ops:
 	nvme_fc_term_aen_ops(ctrl);
-	nvme_stop_keep_alive(&ctrl->ctrl);
 out_disconnect_admin_queue:
 	/* send a Disconnect(association) LS to fc-nvme target */
 	nvme_fc_xmt_disconnect_assoc(ctrl);
@@ -2434,8 +2426,6 @@
 {
 	unsigned long flags;
 
-	nvme_stop_keep_alive(&ctrl->ctrl);
-
 	spin_lock_irqsave(&ctrl->lock, flags);
 	ctrl->flags |= FCCTRL_TERMIO;
 	ctrl->iocnt = 0;
@@ -2517,7 +2507,8 @@
 
 	cancel_work_sync(&ctrl->ctrl.reset_work);
 	cancel_delayed_work_sync(&ctrl->connect_work);
-
+	nvme_stop_ctrl(&ctrl->ctrl);
+	nvme_remove_namespaces(&ctrl->ctrl);
 	/*
 	 * kill the association on the link side.  this will block
 	 * waiting for io to terminate
@@ -2612,6 +2603,7 @@
 		container_of(work, struct nvme_fc_ctrl, ctrl.reset_work);
 	int ret;
 
+	nvme_stop_ctrl(&ctrl->ctrl);
 	/* will block will waiting for io to terminate */
 	nvme_fc_delete_association(ctrl);