nvmet: register discovery subsystem as 'current'

Register the discovery subsystem as the 'current' discovery subsystem,
and add a new discovery log page entry for it.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/target/core.c

@@ -1541,6 +1541,7 @@ struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
 		subsys->max_qid = NVMET_NR_QUEUES;
 		break;
 	case NVME_NQN_DISC:
+	case NVME_NQN_CURR:
 		subsys->max_qid = 0;
 		break;
 	default:

drivers/nvme/target/discovery.c

@@ -146,7 +146,7 @@ static size_t discovery_log_entries(struct nvmet_req *req)
 	struct nvmet_ctrl *ctrl = req->sq->ctrl;
 	struct nvmet_subsys_link *p;
 	struct nvmet_port *r;
-	size_t entries = 0;
+	size_t entries = 1;
 
 	list_for_each_entry(p, &req->port->subsystems, entry) {
 		if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn))
@@ -171,6 +171,7 @@ static void nvmet_execute_disc_get_log_page(struct nvmet_req *req)
 	u32 numrec = 0;
 	u16 status = 0;
 	void *buffer;
+	char traddr[NVMF_TRADDR_SIZE];
 
 	if (!nvmet_check_transfer_len(req, data_len))
 		return;
@@ -203,15 +204,19 @@ static void nvmet_execute_disc_get_log_page(struct nvmet_req *req)
 		status = NVME_SC_INTERNAL;
 		goto out;
 	}
-
 	hdr = buffer;
-	list_for_each_entry(p, &req->port->subsystems, entry) {
-		char traddr[NVMF_TRADDR_SIZE];
 
+	nvmet_set_disc_traddr(req, req->port, traddr);
+
+	nvmet_format_discovery_entry(hdr, req->port,
+				     nvmet_disc_subsys->subsysnqn,
+				     traddr, NVME_NQN_CURR, numrec);
+	numrec++;
+
+	list_for_each_entry(p, &req->port->subsystems, entry) {
 		if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn))
 			continue;
 
-		nvmet_set_disc_traddr(req, req->port, traddr);
 		nvmet_format_discovery_entry(hdr, req->port,
 				p->subsys->subsysnqn, traddr,
 				NVME_NQN_NVME, numrec);
@@ -389,7 +394,7 @@ u16 nvmet_parse_discovery_cmd(struct nvmet_req *req)
 int __init nvmet_init_discovery(void)
 {
 	nvmet_disc_subsys =
-		nvmet_subsys_alloc(NVME_DISC_SUBSYS_NAME, NVME_NQN_DISC);
+		nvmet_subsys_alloc(NVME_DISC_SUBSYS_NAME, NVME_NQN_CURR);
 	return PTR_ERR_OR_ZERO(nvmet_disc_subsys);
 }