nvmet: return bool from nvmet_passthru_ctrl and nvmet_is_passthru_req

The target core code never needs the host-side nvme_ctrl structure.
Open code two uses of nvmet_is_passthru_req in passthru.c, and then
switch the helpers used by the core to return bool.  Also rename the
fuctions to better match their usage:

  nvmet_passthru_ctrl -> nvmet_is_passthru_subsys
  nvmet_req_passthru_ctrl -> nvmet_is_passthru_req

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

drivers/nvme/target/admin-cmd.c

@@ -1015,7 +1015,7 @@ u16 nvmet_parse_admin_cmd(struct nvmet_req *req)
 	if (unlikely(ret))
 		return ret;
 
-	if (nvmet_req_passthru_ctrl(req))
+	if (nvmet_is_passthru_req(req))
 		return nvmet_parse_passthru_admin_cmd(req);
 
 	switch (cmd->common.opcode) {

drivers/nvme/target/configfs.c

@@ -1028,7 +1028,7 @@ nvmet_subsys_attr_version_store_locked(struct nvmet_subsys *subsys,
 	}
 
 	/* passthru subsystems use the underlying controller's version */
-	if (nvmet_passthru_ctrl(subsys))
+	if (nvmet_is_passthru_subsys(subsys))
 		return -EINVAL;
 
 	ret = sscanf(page, "%d.%d.%d\n", &major, &minor, &tertiary);

drivers/nvme/target/core.c

@@ -553,7 +553,7 @@ int nvmet_ns_enable(struct nvmet_ns *ns)
 	mutex_lock(&subsys->lock);
 	ret = 0;
 
-	if (nvmet_passthru_ctrl(subsys)) {
+	if (nvmet_is_passthru_subsys(subsys)) {
 		pr_info("cannot enable both passthru and regular namespaces for a single subsystem");
 		goto out_unlock;
 	}
@@ -869,7 +869,7 @@ static u16 nvmet_parse_io_cmd(struct nvmet_req *req)
 	if (unlikely(ret))
 		return ret;
 
-	if (nvmet_req_passthru_ctrl(req))
+	if (nvmet_is_passthru_req(req))
 		return nvmet_parse_passthru_io_cmd(req);
 
 	ret = nvmet_req_find_ns(req);
@@ -1207,7 +1207,7 @@ static void nvmet_init_cap(struct nvmet_ctrl *ctrl)
 	/* maximum queue entries supported: */
 	ctrl->cap |= NVMET_QUEUE_SIZE - 1;
 
-	if (nvmet_passthru_ctrl(ctrl->subsys))
+	if (nvmet_is_passthru_subsys(ctrl->subsys))
 		nvmet_passthrough_override_cap(ctrl);
 }
 

drivers/nvme/target/nvmet.h

@@ -582,7 +582,7 @@ int nvmet_passthru_ctrl_enable(struct nvmet_subsys *subsys);
 void nvmet_passthru_ctrl_disable(struct nvmet_subsys *subsys);
 u16 nvmet_parse_passthru_admin_cmd(struct nvmet_req *req);
 u16 nvmet_parse_passthru_io_cmd(struct nvmet_req *req);
-static inline struct nvme_ctrl *nvmet_passthru_ctrl(struct nvmet_subsys *subsys)
+static inline bool nvmet_is_passthru_subsys(struct nvmet_subsys *subsys)
 {
 	return subsys->passthru_ctrl;
 }
@@ -601,16 +601,15 @@ static inline u16 nvmet_parse_passthru_io_cmd(struct nvmet_req *req)
 {
 	return 0;
 }
-static inline struct nvme_ctrl *nvmet_passthru_ctrl(struct nvmet_subsys *subsys)
+static inline bool nvmet_is_passthru_subsys(struct nvmet_subsys *subsys)
 {
 	return NULL;
 }
 #endif /* CONFIG_NVME_TARGET_PASSTHRU */
 
-static inline struct nvme_ctrl *
-nvmet_req_passthru_ctrl(struct nvmet_req *req)
+static inline bool nvmet_is_passthru_req(struct nvmet_req *req)
 {
-	return nvmet_passthru_ctrl(nvmet_req_subsys(req));
+	return nvmet_is_passthru_subsys(nvmet_req_subsys(req));
 }
 
 void nvmet_passthrough_override_cap(struct nvmet_ctrl *ctrl);

drivers/nvme/target/passthru.c

@@ -228,7 +228,7 @@ static int nvmet_passthru_map_sg(struct nvmet_req *req, struct request *rq)
 
 static void nvmet_passthru_execute_cmd(struct nvmet_req *req)
 {
-	struct nvme_ctrl *ctrl = nvmet_req_passthru_ctrl(req);
+	struct nvme_ctrl *ctrl = nvmet_req_subsys(req)->passthru_ctrl;
 	struct request_queue *q = ctrl->admin_q;
 	struct nvme_ns *ns = NULL;
 	struct request *rq = NULL;
@@ -309,7 +309,7 @@ out:
  */
 static void nvmet_passthru_set_host_behaviour(struct nvmet_req *req)
 {
-	struct nvme_ctrl *ctrl = nvmet_req_passthru_ctrl(req);
+	struct nvme_ctrl *ctrl = nvmet_req_subsys(req)->passthru_ctrl;
 	struct nvme_feat_host_behavior *host;
 	u16 status = NVME_SC_INTERNAL;
 	int ret;