[PATCH V3 03/10] nvme: centralize queue action nvme_kill_queues()

[Chaitanya Kulkarni]

There is no point in having 7 different functions which are differing
with just one line.

The helper functions for ctrl queue management can be centralized with
the help of the descriptive enums for action. This avoids code
duplication which spans across the 7 functions as compare to one
function and exporting 7 symbols as compare to one symbol.

This patch merges nvme_kill_queue() into newly introduced
nvme_queue_act() which handles the queue management.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni at wdc.com>
---
 drivers/nvme/host/core.c | 37 ++++++++++++++++++++++---------------
 drivers/nvme/host/nvme.h |  6 +++++-
 drivers/nvme/host/pci.c  |  4 ++--
 3 files changed, 29 insertions(+), 18 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 297835bda996..b39aafcbdde9 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -4107,7 +4107,7 @@ void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
 	 * potentially having to clean up the failed sync later.
 	 */
 	if (ctrl->state == NVME_CTRL_DEAD)
-		nvme_kill_queues(ctrl);
+		nvme_queue_act(ctrl, NVME_KILL_QUEUES);
 
 	xa_lock(&ctrl->namespaces);
 	xa_for_each(&ctrl->namespaces, idx, ns) {
@@ -4452,26 +4452,33 @@ int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
 }
 EXPORT_SYMBOL_GPL(nvme_init_ctrl);
 
-/**
- * nvme_kill_queues(): Ends all namespace queues
- * @ctrl: the dead controller that needs to end
- *
- * Call this function when the driver determines it is unable to get the
- * controller in a state capable of servicing IO.
- */
-void nvme_kill_queues(struct nvme_ctrl *ctrl)
+void nvme_queue_act(struct nvme_ctrl *ctrl, enum nvme_queue_act op)
 {
 	struct nvme_ns *ns;
 	unsigned long idx;
 
-	/* Forcibly unquiesce queues to avoid blocking dispatch */
-	if (ctrl->admin_q && !blk_queue_dying(ctrl->admin_q))
-		blk_mq_unquiesce_queue(ctrl->admin_q);
+	switch (op) {
+	case NVME_KILL_QUEUES:
+		/* Forcibly unquiesce queues to avoid blocking dispatch */
+		if (ctrl->admin_q && !blk_queue_dying(ctrl->admin_q))
+			blk_mq_unquiesce_queue(ctrl->admin_q);
+		break;
+	default:
+		break;
+	}
 
-	xa_for_each(&ctrl->namespaces, idx, ns)
-		nvme_set_queue_dying(ns);
+	xa_for_each(&ctrl->namespaces, idx, ns) {
+		switch (op) {
+		case NVME_KILL_QUEUES:
+			nvme_set_queue_dying(ns);
+			break;
+		default:
+			pr_warn("invalid %s op 0x%x\n", __func__, op);
+			break;
+		}
+	}
 }
-EXPORT_SYMBOL_GPL(nvme_kill_queues);
+EXPORT_SYMBOL_GPL(nvme_queue_act);
 
 void nvme_unfreeze(struct nvme_ctrl *ctrl)
 {
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 1e8dedee74df..b1cde85e9a85 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -545,9 +545,13 @@ int nvme_sec_submit(void *data, u16 spsp, u8 secp, void *buffer, size_t len,
 void nvme_complete_async_event(struct nvme_ctrl *ctrl, __le16 status,
 		volatile union nvme_result *res);
 
+enum nvme_queue_act {
+	NVME_KILL_QUEUES = 1,
+};
+
+void nvme_queue_act(struct nvme_ctrl *ctrl, enum nvme_queue_act op);
 void nvme_stop_queues(struct nvme_ctrl *ctrl);
 void nvme_start_queues(struct nvme_ctrl *ctrl);
-void nvme_kill_queues(struct nvme_ctrl *ctrl);
 void nvme_sync_queues(struct nvme_ctrl *ctrl);
 void nvme_unfreeze(struct nvme_ctrl *ctrl);
 void nvme_wait_freeze(struct nvme_ctrl *ctrl);
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 19e27dd17108..ce04a76a48af 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2509,7 +2509,7 @@ static void nvme_remove_dead_ctrl(struct nvme_dev *dev)
 	nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
 	nvme_get_ctrl(&dev->ctrl);
 	nvme_dev_disable(dev, false);
-	nvme_kill_queues(&dev->ctrl);
+	nvme_queue_act(&dev->ctrl, NVME_KILL_QUEUES);
 	if (!queue_work(nvme_wq, &dev->remove_work))
 		nvme_put_ctrl(&dev->ctrl);
 }
@@ -2617,7 +2617,7 @@ static void nvme_reset_work(struct work_struct *work)
 	 */
 	if (dev->online_queues < 2) {
 		dev_warn(dev->ctrl.device, "IO queues not created\n");
-		nvme_kill_queues(&dev->ctrl);
+		nvme_queue_act(&dev->ctrl, NVME_KILL_QUEUES);
 		nvme_remove_namespaces(&dev->ctrl);
 		nvme_free_tagset(dev);
 	} else {
-- 
2.26.0