From: Nicholas Bellinger <[email protected]> This patch introduces loopback support for a nvme host controller per nvmet_port instance model, following what we've done in drivers/target/loopback/ for allowing multiple host LLDs to co-exist.
It changes nvme_loop_add_port() to use struct nvme_loop_port and take the nvmf_host_add() reference, and invokes device_register() to nvme_loop_driver_probe() to kick off controller creation within nvme_loop_create_ctrl(). This allows nvme_loop_queue_rq to setup iod->req.port to the per nvmet_port pointer, instead of a single hardcoded global nvmet_loop_port. Subsequently, it also adds nvme_loop_remove_port() to call device_unregister() and call nvme_loop_del_ctrl() and nvmf_free_options() to drop nvmet_port's struct nvmf_host rereference, when the nvmet_port_binding is being removed from the associated nvmet_subsys. Cc: Jens Axboe <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Keith Busch <[email protected]> Cc: Jay Freyensee <[email protected]> Cc: Martin Petersen <[email protected]> Cc: Sagi Grimberg <[email protected]> Cc: Hannes Reinecke <[email protected]> Cc: Mike Christie <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> --- drivers/nvme/target/loop.c | 205 ++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 185 insertions(+), 20 deletions(-) diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c index 08b4fbb..e9f31d4 100644 --- a/drivers/nvme/target/loop.c +++ b/drivers/nvme/target/loop.c @@ -45,6 +45,13 @@ struct nvme_loop_iod { struct scatterlist first_sgl[]; }; +struct nvme_loop_port { + struct device dev; + struct nvmf_ctrl_options *opts; + struct nvme_ctrl *ctrl; + struct nvmet_port port; +}; + struct nvme_loop_ctrl { spinlock_t lock; struct nvme_loop_queue *queues; @@ -61,6 +68,8 @@ struct nvme_loop_ctrl { struct nvmet_ctrl *target_ctrl; struct work_struct delete_work; struct work_struct reset_work; + + struct nvme_loop_port *port; }; static inline struct nvme_loop_ctrl *to_loop_ctrl(struct nvme_ctrl *ctrl) @@ -74,8 +83,6 @@ struct nvme_loop_queue { struct nvme_loop_ctrl *ctrl; }; -static struct nvmet_port *nvmet_loop_port; - static LIST_HEAD(nvme_loop_ctrl_list); static DEFINE_MUTEX(nvme_loop_ctrl_mutex); @@ -172,7 +179,8 @@ static int nvme_loop_queue_rq(struct blk_mq_hw_ctx *hctx, return ret; iod->cmd.common.flags |= NVME_CMD_SGL_METABUF; - iod->req.port = nvmet_loop_port; + iod->req.port = &queue->ctrl->port->port; + if (!nvmet_req_init(&iod->req, &queue->nvme_cq, &queue->nvme_sq, &nvme_loop_ops)) { nvme_cleanup_cmd(req); @@ -599,6 +607,8 @@ out_destroy_queues: static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev, struct nvmf_ctrl_options *opts) { + struct nvme_loop_port *loop_port = container_of(dev, + struct nvme_loop_port, dev); struct nvme_loop_ctrl *ctrl; bool changed; int ret; @@ -607,6 +617,7 @@ static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev, if (!ctrl) return ERR_PTR(-ENOMEM); ctrl->ctrl.opts = opts; + ctrl->port = loop_port; INIT_LIST_HEAD(&ctrl->list); INIT_WORK(&ctrl->delete_work, nvme_loop_del_ctrl_work); @@ -681,29 +692,135 @@ out_put_ctrl: return ERR_PTR(ret); } -static int nvme_loop_add_port(struct nvmet_port *port) +static int nvme_loop_driver_probe(struct device *dev) { - /* - * XXX: disalow adding more than one port so - * there is no connection rejections when a - * a subsystem is assigned to a port for which - * loop doesn't have a pointer. - * This scenario would be possible if we allowed - * more than one port to be added and a subsystem - * was assigned to a port other than nvmet_loop_port. - */ + struct nvme_loop_port *loop_port = container_of(dev, + struct nvme_loop_port, dev); + struct nvme_ctrl *ctrl; - if (nvmet_loop_port) - return -EPERM; + ctrl = nvme_loop_create_ctrl(dev, loop_port->opts); + if (IS_ERR(ctrl)) + return PTR_ERR(ctrl); - nvmet_loop_port = port; + loop_port->ctrl = ctrl; return 0; } -static void nvme_loop_remove_port(struct nvmet_port *port) +static int nvme_loop_driver_remove(struct device *dev) +{ + struct nvme_loop_port *loop_port = container_of(dev, + struct nvme_loop_port, dev); + struct nvme_ctrl *ctrl = loop_port->ctrl; + struct nvmf_ctrl_options *opts = loop_port->opts; + + nvme_loop_del_ctrl(ctrl); + nvmf_free_options(opts); + return 0; +} + +static int pseudo_bus_match(struct device *dev, + struct device_driver *dev_driver) +{ + return 1; +} + +static struct bus_type nvme_loop_bus = { + .name = "nvme_loop_bus", + .match = pseudo_bus_match, + .probe = nvme_loop_driver_probe, + .remove = nvme_loop_driver_remove, +}; + +static struct device_driver nvme_loop_driverfs = { + .name = "nvme_loop", + .bus = &nvme_loop_bus, +}; + +static void nvme_loop_release_adapter(struct device *dev) { - if (port == nvmet_loop_port) - nvmet_loop_port = NULL; + struct nvme_loop_port *loop_port = container_of(dev, + struct nvme_loop_port, dev); + + kfree(loop_port); +} + +static struct device *nvme_loop_primary; + +static int nvme_loop_add_port(struct nvmet_port_binding *pb) +{ + struct nvmet_subsys *subsys = pb->nf_subsys; + struct nvme_loop_port *loop_port; + struct nvmf_ctrl_options *opts; + struct device *dev; + int ret; + + loop_port = kzalloc(sizeof(*loop_port), GFP_KERNEL); + if (!loop_port) + return -ENOMEM; + + mutex_init(&loop_port->port.port_binding_mutex); + INIT_LIST_HEAD(&loop_port->port.port_binding_list); + loop_port->port.priv = loop_port; + loop_port->port.nf_subsys = pb->nf_subsys; + loop_port->port.nf_ops = pb->nf_ops; + pb->port = &loop_port->port; + + opts = kzalloc(sizeof(*opts), GFP_KERNEL); + if (!opts) { + kfree(loop_port); + return -ENOMEM; + } + loop_port->opts = opts; + + /* Set defaults */ + opts->queue_size = NVMF_DEF_QUEUE_SIZE; + opts->nr_io_queues = num_online_cpus(); + opts->tl_retry_count = 2; + opts->reconnect_delay = NVMF_DEF_RECONNECT_DELAY; + opts->kato = NVME_DEFAULT_KATO; + + opts->host = nvmf_host_add(NULL); + if (!opts->host) { + kfree(opts); + kfree(loop_port); + return -ENOMEM; + } + + opts->transport = kstrdup("loop", GFP_KERNEL); + opts->subsysnqn = kstrdup(subsys->subsysnqn, GFP_KERNEL); + + dev = &loop_port->dev; + dev->bus = &nvme_loop_bus; + dev->parent = nvme_loop_primary; + dev->release = &nvme_loop_release_adapter; + dev_set_name(dev, "nvme_loop_ctrl:%s", subsys->subsysnqn); + + nvmet_port_binding_enable(pb, &loop_port->port); + + ret = device_register(dev); + if (ret) { + pr_err("device_register() failed: %d\n", ret); + nvmet_port_binding_disable(pb, &loop_port->port); + nvmf_free_options(opts); + kfree(loop_port); + return ret; + } + + return 0; +} + +static void nvme_loop_remove_port(struct nvmet_port_binding *pb) +{ + struct nvmet_port *port = pb->port; + struct nvme_loop_port *loop_port; + + if (!port) + return; + + loop_port = container_of(port, struct nvme_loop_port, port); + nvmet_port_binding_disable(pb, &loop_port->port); + + device_unregister(&loop_port->dev); } static struct nvmet_fabrics_ops nvme_loop_ops = { @@ -720,13 +837,59 @@ static struct nvmf_transport_ops nvme_loop_transport = { .create_ctrl = nvme_loop_create_ctrl, }; +static int nvme_loop_alloc_core_bus(void) +{ + int ret; + + nvme_loop_primary = root_device_register("nvme_loop_0"); + if (IS_ERR(nvme_loop_primary)) { + pr_err("Unable to allocate nvme_loop_primary\n"); + return PTR_ERR(nvme_loop_primary); + } + + ret = bus_register(&nvme_loop_bus); + if (ret) { + pr_err("bus_register() failed for nvme_loop_bus\n"); + goto dev_unreg; + } + + ret = driver_register(&nvme_loop_driverfs); + if (ret) { + pr_err("driver_register() failed for" + " nvme_loop_driverfs\n"); + goto bus_unreg; + } + + return ret; + +bus_unreg: + bus_unregister(&nvme_loop_bus); +dev_unreg: + root_device_unregister(nvme_loop_primary); + return ret; +} + +static void nvme_loop_release_core_bus(void) +{ + driver_unregister(&nvme_loop_driverfs); + bus_unregister(&nvme_loop_bus); + root_device_unregister(nvme_loop_primary); +} + static int __init nvme_loop_init_module(void) { int ret; - ret = nvmet_register_transport(&nvme_loop_ops); + ret = nvme_loop_alloc_core_bus(); if (ret) return ret; + + ret = nvmet_register_transport(&nvme_loop_ops); + if (ret) { + nvme_loop_release_core_bus(); + return ret; + } + nvmf_register_transport(&nvme_loop_transport); return 0; } @@ -744,6 +907,8 @@ static void __exit nvme_loop_cleanup_module(void) mutex_unlock(&nvme_loop_ctrl_mutex); flush_scheduled_work(); + + nvme_loop_release_core_bus(); } module_init(nvme_loop_init_module); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
