The namespace disk names must be unique for the lifetime of the subsystem. This was accomplished by using their parent subsystems' instances which were allocated independently from the controllers connected to that subsystem. This allowed name prefixes assigned to namespaces to match a controller from an unrelated subsystem, and has created confusion among users examining device nodes.

Ensure a namespace's subsystem instance never clashes with a controller instance of another subsystem by transferring the instance ownership to the parent subsystem from the first controller discovered in that subsystem.

Reviewed-by: Logan Gunthorpe logang@deltatee.com Signed-off-by: Keith Busch kbusch@kernel.org Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Minwoo Im minwoo.im@samsung.com Reviewed-by: Hannes Reinecke hare@suse.com Reviewed-off-by: Sagi Grimberg sagi@grimberg.me Signed-off-by: Sagi Grimberg sagi@grimberg.me --- drivers/nvme/host/core.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 8c760493354f..576da5820a57 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -88,7 +88,6 @@ EXPORT_SYMBOL_GPL(nvme_reset_wq); struct workqueue_struct *nvme_delete_wq; EXPORT_SYMBOL_GPL(nvme_delete_wq);

-static DEFINE_IDA(nvme_subsystems_ida); static LIST_HEAD(nvme_subsystems); static DEFINE_MUTEX(nvme_subsystems_lock);

@@ -2308,7 +2307,8 @@ static void nvme_release_subsystem(struct device *dev) struct nvme_subsystem *subsys = container_of(dev, struct nvme_subsystem, dev);

- ida_simple_remove(&nvme_subsystems_ida, subsys->instance); + if (subsys->instance >= 0) + ida_simple_remove(&nvme_instance_ida, subsys->instance); kfree(subsys); }

@@ -2419,12 +2419,8 @@ static int nvme_init_subsystem(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id) 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; + + subsys->instance = -1; mutex_init(&subsys->lock); kref_init(&subsys->ref); INIT_LIST_HEAD(&subsys->ctrls); @@ -2439,7 +2435,7 @@ static int nvme_init_subsystem(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id) subsys->dev.class = nvme_subsys_class; subsys->dev.release = nvme_release_subsystem; subsys->dev.groups = nvme_subsys_attrs_groups; - dev_set_name(&subsys->dev, "nvme-subsys%d", subsys->instance); + dev_set_name(&subsys->dev, "nvme-subsys%d", ctrl->instance); device_initialize(&subsys->dev);

mutex_lock(&nvme_subsystems_lock); @@ -2472,6 +2468,8 @@ static int nvme_init_subsystem(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id) list_add_tail(&subsys->entry, &nvme_subsystems); }

+ if (!found) + subsys->instance = ctrl->instance; ctrl->subsys = subsys; mutex_unlock(&nvme_subsystems_lock);

@@ -3749,7 +3747,9 @@ static void nvme_free_ctrl(struct device *dev) container_of(dev, struct nvme_ctrl, ctrl_device); struct nvme_subsystem *subsys = ctrl->subsys;

- ida_simple_remove(&nvme_instance_ida, ctrl->instance); + if (subsys && ctrl->instance != subsys->instance) + ida_simple_remove(&nvme_instance_ida, ctrl->instance); + kfree(ctrl->effects); nvme_mpath_uninit(ctrl); __free_page(ctrl->discard_page); @@ -4009,7 +4009,6 @@ int __init nvme_core_init(void)

void nvme_core_exit(void) { - ida_destroy(&nvme_subsystems_ida); class_destroy(nvme_subsys_class); class_destroy(nvme_class); unregister_chrdev_region(nvme_chr_devt, NVME_MINORS);