nvmet: Cleanup discovery execute handlers

Push the lid and cns check into their respective handlers and, while
we're at it, rename the functions to be consistent with other
discovery handlers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
[split patch, update changelog]
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/nvme/target/discovery.c

@@ -157,7 +157,7 @@ static size_t discovery_log_entries(struct nvmet_req *req)
 	return entries;
 }
 
-static void nvmet_execute_get_disc_log_page(struct nvmet_req *req)
+static void nvmet_execute_disc_get_log_page(struct nvmet_req *req)
 {
 	const int entry_size = sizeof(struct nvmf_disc_rsp_page_entry);
 	struct nvmet_ctrl *ctrl = req->sq->ctrl;
@@ -171,6 +171,13 @@ static void nvmet_execute_get_disc_log_page(struct nvmet_req *req)
 	u16 status = 0;
 	void *buffer;
 
+	if (req->cmd->get_log_page.lid != NVME_LOG_DISC) {
+		req->error_loc =
+			offsetof(struct nvme_get_log_page_command, lid);
+		status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+		goto out;
+	}
+
 	/* Spec requires dword aligned offsets */
 	if (offset & 0x3) {
 		status = NVME_SC_INVALID_FIELD | NVME_SC_DNR;
@@ -227,12 +234,18 @@ static void nvmet_execute_get_disc_log_page(struct nvmet_req *req)
 	nvmet_req_complete(req, status);
 }
 
-static void nvmet_execute_identify_disc_ctrl(struct nvmet_req *req)
+static void nvmet_execute_disc_identify(struct nvmet_req *req)
 {
 	struct nvmet_ctrl *ctrl = req->sq->ctrl;
 	struct nvme_id_ctrl *id;
 	u16 status = 0;
 
+	if (req->cmd->identify.cns != NVME_ID_CNS_CTRL) {
+		req->error_loc = offsetof(struct nvme_identify, cns);
+		status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+		goto out;
+	}
+
 	id = kzalloc(sizeof(*id), GFP_KERNEL);
 	if (!id) {
 		status = NVME_SC_INTERNAL;
@@ -344,31 +357,12 @@ u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
 		return 0;
 	case nvme_admin_get_log_page:
 		req->data_len = nvmet_get_log_page_len(cmd);
-
-		switch (cmd->get_log_page.lid) {
-		case NVME_LOG_DISC:
-			req->execute = nvmet_execute_get_disc_log_page;
+		req->execute = nvmet_execute_disc_get_log_page;
 		return 0;
-		default:
-			pr_err("unsupported get_log_page lid %d\n",
-			       cmd->get_log_page.lid);
-			req->error_loc =
-				offsetof(struct nvme_get_log_page_command, lid);
-			return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
-		}
 	case nvme_admin_identify:
 		req->data_len = NVME_IDENTIFY_DATA_SIZE;
-		switch (cmd->identify.cns) {
-		case NVME_ID_CNS_CTRL:
-			req->execute =
-				nvmet_execute_identify_disc_ctrl;
+		req->execute = nvmet_execute_disc_identify;
 		return 0;
-		default:
-			pr_err("unsupported identify cns %d\n",
-			       cmd->identify.cns);
-			req->error_loc = offsetof(struct nvme_identify, cns);
-			return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
-		}
 	default:
 		pr_err("unhandled cmd %d\n", cmd->common.opcode);
 		req->error_loc = offsetof(struct nvme_common_command, opcode);