+static int nvme_init_subsystem(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id)
+{
+ struct nvme_subsystem *subsys, *found;
+ int ret;
+
+ subsys = kzalloc(sizeof(*subsys), GFP_KERNEL);
+ if (!subsys)
+ return -ENOMEM;
+ ret = ida_simple_get(&nvme_subsystems_ida, 0, 0, GFP_KERNEL);
+ if (ret < 0) {
+ kfree(subsys);
+ return ret;
+ }
+ subsys->instance = ret;
+ mutex_init(&subsys->lock);
+ kref_init(&subsys->ref);
+ INIT_LIST_HEAD(&subsys->ctrls);
+ nvme_init_subnqn(subsys, ctrl, id);
+ memcpy(subsys->serial, id->sn, sizeof(subsys->serial));
+ memcpy(subsys->model, id->mn, sizeof(subsys->model));
+ memcpy(subsys->firmware_rev, id->fr, sizeof(subsys->firmware_rev));
+ subsys->vendor_id = le16_to_cpu(id->vid);
+ subsys->cmic = id->cmic;
+
+ subsys->dev.class = nvme_subsys_class;
+ subsys->dev.release = nvme_release_subsystem;
+ dev_set_name(&subsys->dev, "nvme-subsys%d", subsys->instance);
+ device_initialize(&subsys->dev);
+
Any reason to do all this before we know if we found an existing
subsystem? Also can the enumeration become with "holes" because you
acquire a subsystem ida temporarily and free it (and another subsystem
just came in)? Not a big issue though...