diff options
Diffstat (limited to 'drivers/nvme/target/core.c')
| -rw-r--r-- | drivers/nvme/target/core.c | 1260 |
1 files changed, 1260 insertions, 0 deletions
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c new file mode 100644 index 000000000..1a35d73c3 --- /dev/null +++ b/drivers/nvme/target/core.c @@ -0,0 +1,1260 @@ +/* + * Common code for the NVMe target. + * Copyright (c) 2015-2016 HGST, a Western Digital Company. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/module.h> +#include <linux/random.h> +#include <linux/rculist.h> + +#include "nvmet.h" + +struct workqueue_struct *buffered_io_wq; +static const struct nvmet_fabrics_ops *nvmet_transports[NVMF_TRTYPE_MAX]; +static DEFINE_IDA(cntlid_ida); + +/* + * This read/write semaphore is used to synchronize access to configuration + * information on a target system that will result in discovery log page + * information change for at least one host. + * The full list of resources to protected by this semaphore is: + * + * - subsystems list + * - per-subsystem allowed hosts list + * - allow_any_host subsystem attribute + * - nvmet_genctr + * - the nvmet_transports array + * + * When updating any of those lists/structures write lock should be obtained, + * while when reading (popolating discovery log page or checking host-subsystem + * link) read lock is obtained to allow concurrent reads. + */ +DECLARE_RWSEM(nvmet_config_sem); + +u32 nvmet_ana_group_enabled[NVMET_MAX_ANAGRPS + 1]; +u64 nvmet_ana_chgcnt; +DECLARE_RWSEM(nvmet_ana_sem); + +static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port, + const char *subsysnqn); + +u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf, + size_t len) +{ + if (sg_pcopy_from_buffer(req->sg, req->sg_cnt, buf, len, off) != len) + return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR; + return 0; +} + +u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf, size_t len) +{ + if (sg_pcopy_to_buffer(req->sg, req->sg_cnt, buf, len, off) != len) + return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR; + return 0; +} + +u16 nvmet_zero_sgl(struct nvmet_req *req, off_t off, size_t len) +{ + if (sg_zero_buffer(req->sg, req->sg_cnt, len, off) != len) + return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR; + return 0; +} + +static unsigned int nvmet_max_nsid(struct nvmet_subsys *subsys) +{ + struct nvmet_ns *ns; + + if (list_empty(&subsys->namespaces)) + return 0; + + ns = list_last_entry(&subsys->namespaces, struct nvmet_ns, dev_link); + return ns->nsid; +} + +static u32 nvmet_async_event_result(struct nvmet_async_event *aen) +{ + return aen->event_type | (aen->event_info << 8) | (aen->log_page << 16); +} + +static void nvmet_async_events_free(struct nvmet_ctrl *ctrl) +{ + struct nvmet_req *req; + + while (1) { + mutex_lock(&ctrl->lock); + if (!ctrl->nr_async_event_cmds) { + mutex_unlock(&ctrl->lock); + return; + } + + req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds]; + mutex_unlock(&ctrl->lock); + nvmet_req_complete(req, NVME_SC_INTERNAL | NVME_SC_DNR); + } +} + +static void nvmet_async_event_work(struct work_struct *work) +{ + struct nvmet_ctrl *ctrl = + container_of(work, struct nvmet_ctrl, async_event_work); + struct nvmet_async_event *aen; + struct nvmet_req *req; + + while (1) { + mutex_lock(&ctrl->lock); + aen = list_first_entry_or_null(&ctrl->async_events, + struct nvmet_async_event, entry); + if (!aen || !ctrl->nr_async_event_cmds) { + mutex_unlock(&ctrl->lock); + return; + } + + req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds]; + nvmet_set_result(req, nvmet_async_event_result(aen)); + + list_del(&aen->entry); + kfree(aen); + + mutex_unlock(&ctrl->lock); + nvmet_req_complete(req, 0); + } +} + +static void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type, + u8 event_info, u8 log_page) +{ + struct nvmet_async_event *aen; + + aen = kmalloc(sizeof(*aen), GFP_KERNEL); + if (!aen) + return; + + aen->event_type = event_type; + aen->event_info = event_info; + aen->log_page = log_page; + + mutex_lock(&ctrl->lock); + list_add_tail(&aen->entry, &ctrl->async_events); + mutex_unlock(&ctrl->lock); + + schedule_work(&ctrl->async_event_work); +} + +static bool nvmet_aen_disabled(struct nvmet_ctrl *ctrl, u32 aen) +{ + if (!(READ_ONCE(ctrl->aen_enabled) & aen)) + return true; + return test_and_set_bit(aen, &ctrl->aen_masked); +} + +static void nvmet_add_to_changed_ns_log(struct nvmet_ctrl *ctrl, __le32 nsid) +{ + u32 i; + + mutex_lock(&ctrl->lock); + if (ctrl->nr_changed_ns > NVME_MAX_CHANGED_NAMESPACES) + goto out_unlock; + + for (i = 0; i < ctrl->nr_changed_ns; i++) { + if (ctrl->changed_ns_list[i] == nsid) + goto out_unlock; + } + + if (ctrl->nr_changed_ns == NVME_MAX_CHANGED_NAMESPACES) { + ctrl->changed_ns_list[0] = cpu_to_le32(0xffffffff); + ctrl->nr_changed_ns = U32_MAX; + goto out_unlock; + } + + ctrl->changed_ns_list[ctrl->nr_changed_ns++] = nsid; +out_unlock: + mutex_unlock(&ctrl->lock); +} + +void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid) +{ + struct nvmet_ctrl *ctrl; + + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) { + nvmet_add_to_changed_ns_log(ctrl, cpu_to_le32(nsid)); + if (nvmet_aen_disabled(ctrl, NVME_AEN_CFG_NS_ATTR)) + continue; + nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE, + NVME_AER_NOTICE_NS_CHANGED, + NVME_LOG_CHANGED_NS); + } +} + +void nvmet_send_ana_event(struct nvmet_subsys *subsys, + struct nvmet_port *port) +{ + struct nvmet_ctrl *ctrl; + + mutex_lock(&subsys->lock); + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) { + if (port && ctrl->port != port) + continue; + if (nvmet_aen_disabled(ctrl, NVME_AEN_CFG_ANA_CHANGE)) + continue; + nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE, + NVME_AER_NOTICE_ANA, NVME_LOG_ANA); + } + mutex_unlock(&subsys->lock); +} + +void nvmet_port_send_ana_event(struct nvmet_port *port) +{ + struct nvmet_subsys_link *p; + + down_read(&nvmet_config_sem); + list_for_each_entry(p, &port->subsystems, entry) + nvmet_send_ana_event(p->subsys, port); + up_read(&nvmet_config_sem); +} + +int nvmet_register_transport(const struct nvmet_fabrics_ops *ops) +{ + int ret = 0; + + down_write(&nvmet_config_sem); + if (nvmet_transports[ops->type]) + ret = -EINVAL; + else + nvmet_transports[ops->type] = ops; + up_write(&nvmet_config_sem); + + return ret; +} +EXPORT_SYMBOL_GPL(nvmet_register_transport); + +void nvmet_unregister_transport(const struct nvmet_fabrics_ops *ops) +{ + down_write(&nvmet_config_sem); + nvmet_transports[ops->type] = NULL; + up_write(&nvmet_config_sem); +} +EXPORT_SYMBOL_GPL(nvmet_unregister_transport); + +int nvmet_enable_port(struct nvmet_port *port) +{ + const struct nvmet_fabrics_ops *ops; + int ret; + + lockdep_assert_held(&nvmet_config_sem); + + ops = nvmet_transports[port->disc_addr.trtype]; + if (!ops) { + up_write(&nvmet_config_sem); + request_module("nvmet-transport-%d", port->disc_addr.trtype); + down_write(&nvmet_config_sem); + ops = nvmet_transports[port->disc_addr.trtype]; + if (!ops) { + pr_err("transport type %d not supported\n", + port->disc_addr.trtype); + return -EINVAL; + } + } + + if (!try_module_get(ops->owner)) + return -EINVAL; + + ret = ops->add_port(port); + if (ret) { + module_put(ops->owner); + return ret; + } + + /* If the transport didn't set inline_data_size, then disable it. */ + if (port->inline_data_size < 0) + port->inline_data_size = 0; + + port->enabled = true; + return 0; +} + +void nvmet_disable_port(struct nvmet_port *port) +{ + const struct nvmet_fabrics_ops *ops; + + lockdep_assert_held(&nvmet_config_sem); + + port->enabled = false; + + ops = nvmet_transports[port->disc_addr.trtype]; + ops->remove_port(port); + module_put(ops->owner); +} + +static void nvmet_keep_alive_timer(struct work_struct *work) +{ + struct nvmet_ctrl *ctrl = container_of(to_delayed_work(work), + struct nvmet_ctrl, ka_work); + + pr_err("ctrl %d keep-alive timer (%d seconds) expired!\n", + ctrl->cntlid, ctrl->kato); + + nvmet_ctrl_fatal_error(ctrl); +} + +static void nvmet_start_keep_alive_timer(struct nvmet_ctrl *ctrl) +{ + if (unlikely(ctrl->kato == 0)) + return; + + pr_debug("ctrl %d start keep-alive timer for %d secs\n", + ctrl->cntlid, ctrl->kato); + + INIT_DELAYED_WORK(&ctrl->ka_work, nvmet_keep_alive_timer); + schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ); +} + +static void nvmet_stop_keep_alive_timer(struct nvmet_ctrl *ctrl) +{ + if (unlikely(ctrl->kato == 0)) + return; + + pr_debug("ctrl %d stop keep-alive\n", ctrl->cntlid); + + cancel_delayed_work_sync(&ctrl->ka_work); +} + +static struct nvmet_ns *__nvmet_find_namespace(struct nvmet_ctrl *ctrl, + __le32 nsid) +{ + struct nvmet_ns *ns; + + list_for_each_entry_rcu(ns, &ctrl->subsys->namespaces, dev_link) { + if (ns->nsid == le32_to_cpu(nsid)) + return ns; + } + + return NULL; +} + +struct nvmet_ns *nvmet_find_namespace(struct nvmet_ctrl *ctrl, __le32 nsid) +{ + struct nvmet_ns *ns; + + rcu_read_lock(); + ns = __nvmet_find_namespace(ctrl, nsid); + if (ns) + percpu_ref_get(&ns->ref); + rcu_read_unlock(); + + return ns; +} + +static void nvmet_destroy_namespace(struct percpu_ref *ref) +{ + struct nvmet_ns *ns = container_of(ref, struct nvmet_ns, ref); + + complete(&ns->disable_done); +} + +void nvmet_put_namespace(struct nvmet_ns *ns) +{ + percpu_ref_put(&ns->ref); +} + +static void nvmet_ns_dev_disable(struct nvmet_ns *ns) +{ + nvmet_bdev_ns_disable(ns); + nvmet_file_ns_disable(ns); +} + +int nvmet_ns_enable(struct nvmet_ns *ns) +{ + struct nvmet_subsys *subsys = ns->subsys; + int ret; + + mutex_lock(&subsys->lock); + ret = -EMFILE; + if (subsys->nr_namespaces == NVMET_MAX_NAMESPACES) + goto out_unlock; + ret = 0; + if (ns->enabled) + goto out_unlock; + + ret = nvmet_bdev_ns_enable(ns); + if (ret == -ENOTBLK) + ret = nvmet_file_ns_enable(ns); + if (ret) + goto out_unlock; + + ret = percpu_ref_init(&ns->ref, nvmet_destroy_namespace, + 0, GFP_KERNEL); + if (ret) + goto out_dev_put; + + if (ns->nsid > subsys->max_nsid) + subsys->max_nsid = ns->nsid; + + /* + * The namespaces list needs to be sorted to simplify the implementation + * of the Identify Namepace List subcommand. + */ + if (list_empty(&subsys->namespaces)) { + list_add_tail_rcu(&ns->dev_link, &subsys->namespaces); + } else { + struct nvmet_ns *old; + + list_for_each_entry_rcu(old, &subsys->namespaces, dev_link) { + BUG_ON(ns->nsid == old->nsid); + if (ns->nsid < old->nsid) + break; + } + + list_add_tail_rcu(&ns->dev_link, &old->dev_link); + } + subsys->nr_namespaces++; + + nvmet_ns_changed(subsys, ns->nsid); + ns->enabled = true; + ret = 0; +out_unlock: + mutex_unlock(&subsys->lock); + return ret; +out_dev_put: + nvmet_ns_dev_disable(ns); + goto out_unlock; +} + +void nvmet_ns_disable(struct nvmet_ns *ns) +{ + struct nvmet_subsys *subsys = ns->subsys; + + mutex_lock(&subsys->lock); + if (!ns->enabled) + goto out_unlock; + + ns->enabled = false; + list_del_rcu(&ns->dev_link); + if (ns->nsid == subsys->max_nsid) + subsys->max_nsid = nvmet_max_nsid(subsys); + mutex_unlock(&subsys->lock); + + /* + * Now that we removed the namespaces from the lookup list, we + * can kill the per_cpu ref and wait for any remaining references + * to be dropped, as well as a RCU grace period for anyone only + * using the namepace under rcu_read_lock(). Note that we can't + * use call_rcu here as we need to ensure the namespaces have + * been fully destroyed before unloading the module. + */ + percpu_ref_kill(&ns->ref); + synchronize_rcu(); + wait_for_completion(&ns->disable_done); + percpu_ref_exit(&ns->ref); + + mutex_lock(&subsys->lock); + subsys->nr_namespaces--; + nvmet_ns_changed(subsys, ns->nsid); + nvmet_ns_dev_disable(ns); +out_unlock: + mutex_unlock(&subsys->lock); +} + +void nvmet_ns_free(struct nvmet_ns *ns) +{ + nvmet_ns_disable(ns); + + down_write(&nvmet_ana_sem); + nvmet_ana_group_enabled[ns->anagrpid]--; + up_write(&nvmet_ana_sem); + + kfree(ns->device_path); + kfree(ns); +} + +struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid) +{ + struct nvmet_ns *ns; + + ns = kzalloc(sizeof(*ns), GFP_KERNEL); + if (!ns) + return NULL; + + INIT_LIST_HEAD(&ns->dev_link); + init_completion(&ns->disable_done); + + ns->nsid = nsid; + ns->subsys = subsys; + + down_write(&nvmet_ana_sem); + ns->anagrpid = NVMET_DEFAULT_ANA_GRPID; + nvmet_ana_group_enabled[ns->anagrpid]++; + up_write(&nvmet_ana_sem); + + uuid_gen(&ns->uuid); + ns->buffered_io = false; + + return ns; +} + +static void __nvmet_req_complete(struct nvmet_req *req, u16 status) +{ + u32 old_sqhd, new_sqhd; + u16 sqhd; + + if (status) + nvmet_set_status(req, status); + + if (req->sq->size) { + do { + old_sqhd = req->sq->sqhd; + new_sqhd = (old_sqhd + 1) % req->sq->size; + } while (cmpxchg(&req->sq->sqhd, old_sqhd, new_sqhd) != + old_sqhd); + } + sqhd = req->sq->sqhd & 0x0000FFFF; + req->rsp->sq_head = cpu_to_le16(sqhd); + req->rsp->sq_id = cpu_to_le16(req->sq->qid); + req->rsp->command_id = req->cmd->common.command_id; + + if (req->ns) + nvmet_put_namespace(req->ns); + req->ops->queue_response(req); +} + +void nvmet_req_complete(struct nvmet_req *req, u16 status) +{ + __nvmet_req_complete(req, status); + percpu_ref_put(&req->sq->ref); +} +EXPORT_SYMBOL_GPL(nvmet_req_complete); + +void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq, + u16 qid, u16 size) +{ + cq->qid = qid; + cq->size = size; + + ctrl->cqs[qid] = cq; +} + +void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq, + u16 qid, u16 size) +{ + sq->sqhd = 0; + sq->qid = qid; + sq->size = size; + + ctrl->sqs[qid] = sq; +} + +static void nvmet_confirm_sq(struct percpu_ref *ref) +{ + struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref); + + complete(&sq->confirm_done); +} + +void nvmet_sq_destroy(struct nvmet_sq *sq) +{ + /* + * If this is the admin queue, complete all AERs so that our + * queue doesn't have outstanding requests on it. + */ + if (sq->ctrl && sq->ctrl->sqs && sq->ctrl->sqs[0] == sq) + nvmet_async_events_free(sq->ctrl); + percpu_ref_kill_and_confirm(&sq->ref, nvmet_confirm_sq); + wait_for_completion(&sq->confirm_done); + wait_for_completion(&sq->free_done); + percpu_ref_exit(&sq->ref); + + if (sq->ctrl) { + nvmet_ctrl_put(sq->ctrl); + sq->ctrl = NULL; /* allows reusing the queue later */ + } +} +EXPORT_SYMBOL_GPL(nvmet_sq_destroy); + +static void nvmet_sq_free(struct percpu_ref *ref) +{ + struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref); + + complete(&sq->free_done); +} + +int nvmet_sq_init(struct nvmet_sq *sq) +{ + int ret; + + ret = percpu_ref_init(&sq->ref, nvmet_sq_free, 0, GFP_KERNEL); + if (ret) { + pr_err("percpu_ref init failed!\n"); + return ret; + } + init_completion(&sq->free_done); + init_completion(&sq->confirm_done); + + return 0; +} +EXPORT_SYMBOL_GPL(nvmet_sq_init); + +static inline u16 nvmet_check_ana_state(struct nvmet_port *port, + struct nvmet_ns *ns) +{ + enum nvme_ana_state state = port->ana_state[ns->anagrpid]; + + if (unlikely(state == NVME_ANA_INACCESSIBLE)) + return NVME_SC_ANA_INACCESSIBLE; + if (unlikely(state == NVME_ANA_PERSISTENT_LOSS)) + return NVME_SC_ANA_PERSISTENT_LOSS; + if (unlikely(state == NVME_ANA_CHANGE)) + return NVME_SC_ANA_TRANSITION; + return 0; +} + +static inline u16 nvmet_io_cmd_check_access(struct nvmet_req *req) +{ + if (unlikely(req->ns->readonly)) { + switch (req->cmd->common.opcode) { + case nvme_cmd_read: + case nvme_cmd_flush: + break; + default: + return NVME_SC_NS_WRITE_PROTECTED; + } + } + + return 0; +} + +static u16 nvmet_parse_io_cmd(struct nvmet_req *req) +{ + struct nvme_command *cmd = req->cmd; + u16 ret; + + ret = nvmet_check_ctrl_status(req, cmd); + if (unlikely(ret)) + return ret; + + req->ns = nvmet_find_namespace(req->sq->ctrl, cmd->rw.nsid); + if (unlikely(!req->ns)) + return NVME_SC_INVALID_NS | NVME_SC_DNR; + ret = nvmet_check_ana_state(req->port, req->ns); + if (unlikely(ret)) + return ret; + ret = nvmet_io_cmd_check_access(req); + if (unlikely(ret)) + return ret; + + if (req->ns->file) + return nvmet_file_parse_io_cmd(req); + else + return nvmet_bdev_parse_io_cmd(req); +} + +bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq, + struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops) +{ + u8 flags = req->cmd->common.flags; + u16 status; + + req->cq = cq; + req->sq = sq; + req->ops = ops; + req->sg = NULL; + req->sg_cnt = 0; + req->transfer_len = 0; + req->rsp->status = 0; + req->ns = NULL; + + /* no support for fused commands yet */ + if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) { + status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; + goto fail; + } + + /* + * For fabrics, PSDT field shall describe metadata pointer (MPTR) that + * contains an address of a single contiguous physical buffer that is + * byte aligned. + */ + if (unlikely((flags & NVME_CMD_SGL_ALL) != NVME_CMD_SGL_METABUF)) { + status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; + goto fail; + } + + if (unlikely(!req->sq->ctrl)) + /* will return an error for any Non-connect command: */ + status = nvmet_parse_connect_cmd(req); + else if (likely(req->sq->qid != 0)) + status = nvmet_parse_io_cmd(req); + else if (req->cmd->common.opcode == nvme_fabrics_command) + status = nvmet_parse_fabrics_cmd(req); + else if (req->sq->ctrl->subsys->type == NVME_NQN_DISC) + status = nvmet_parse_discovery_cmd(req); + else + status = nvmet_parse_admin_cmd(req); + + if (status) + goto fail; + + if (unlikely(!percpu_ref_tryget_live(&sq->ref))) { + status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; + goto fail; + } + + return true; + +fail: + __nvmet_req_complete(req, status); + return false; +} +EXPORT_SYMBOL_GPL(nvmet_req_init); + +void nvmet_req_uninit(struct nvmet_req *req) +{ + percpu_ref_put(&req->sq->ref); + if (req->ns) + nvmet_put_namespace(req->ns); +} +EXPORT_SYMBOL_GPL(nvmet_req_uninit); + +void nvmet_req_execute(struct nvmet_req *req) +{ + if (unlikely(req->data_len != req->transfer_len)) + nvmet_req_complete(req, NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR); + else + req->execute(req); +} +EXPORT_SYMBOL_GPL(nvmet_req_execute); + +static inline bool nvmet_cc_en(u32 cc) +{ + return (cc >> NVME_CC_EN_SHIFT) & 0x1; +} + +static inline u8 nvmet_cc_css(u32 cc) +{ + return (cc >> NVME_CC_CSS_SHIFT) & 0x7; +} + +static inline u8 nvmet_cc_mps(u32 cc) +{ + return (cc >> NVME_CC_MPS_SHIFT) & 0xf; +} + +static inline u8 nvmet_cc_ams(u32 cc) +{ + return (cc >> NVME_CC_AMS_SHIFT) & 0x7; +} + +static inline u8 nvmet_cc_shn(u32 cc) +{ + return (cc >> NVME_CC_SHN_SHIFT) & 0x3; +} + +static inline u8 nvmet_cc_iosqes(u32 cc) +{ + return (cc >> NVME_CC_IOSQES_SHIFT) & 0xf; +} + +static inline u8 nvmet_cc_iocqes(u32 cc) +{ + return (cc >> NVME_CC_IOCQES_SHIFT) & 0xf; +} + +static void nvmet_start_ctrl(struct nvmet_ctrl *ctrl) +{ + lockdep_assert_held(&ctrl->lock); + + /* + * Only I/O controllers should verify iosqes,iocqes. + * Strictly speaking, the spec says a discovery controller + * should verify iosqes,iocqes are zeroed, however that + * would break backwards compatibility, so don't enforce it. + */ + if (ctrl->subsys->type != NVME_NQN_DISC && + (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES || + nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES)) { + ctrl->csts = NVME_CSTS_CFS; + return; + } + + if (nvmet_cc_mps(ctrl->cc) != 0 || + nvmet_cc_ams(ctrl->cc) != 0 || + nvmet_cc_css(ctrl->cc) != 0) { + ctrl->csts = NVME_CSTS_CFS; + return; + } + + ctrl->csts = NVME_CSTS_RDY; + + /* + * Controllers that are not yet enabled should not really enforce the + * keep alive timeout, but we still want to track a timeout and cleanup + * in case a host died before it enabled the controller. Hence, simply + * reset the keep alive timer when the controller is enabled. + */ + if (ctrl->kato) + mod_delayed_work(system_wq, &ctrl->ka_work, ctrl->kato * HZ); +} + +static void nvmet_clear_ctrl(struct nvmet_ctrl *ctrl) +{ + lockdep_assert_held(&ctrl->lock); + + /* XXX: tear down queues? */ + ctrl->csts &= ~NVME_CSTS_RDY; + ctrl->cc = 0; +} + +void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new) +{ + u32 old; + + mutex_lock(&ctrl->lock); + old = ctrl->cc; + ctrl->cc = new; + + if (nvmet_cc_en(new) && !nvmet_cc_en(old)) + nvmet_start_ctrl(ctrl); + if (!nvmet_cc_en(new) && nvmet_cc_en(old)) + nvmet_clear_ctrl(ctrl); + if (nvmet_cc_shn(new) && !nvmet_cc_shn(old)) { + nvmet_clear_ctrl(ctrl); + ctrl->csts |= NVME_CSTS_SHST_CMPLT; + } + if (!nvmet_cc_shn(new) && nvmet_cc_shn(old)) + ctrl->csts &= ~NVME_CSTS_SHST_CMPLT; + mutex_unlock(&ctrl->lock); +} + +static void nvmet_init_cap(struct nvmet_ctrl *ctrl) +{ + /* command sets supported: NVMe command set: */ + ctrl->cap = (1ULL << 37); + /* CC.EN timeout in 500msec units: */ + ctrl->cap |= (15ULL << 24); + /* maximum queue entries supported: */ + ctrl->cap |= NVMET_QUEUE_SIZE - 1; +} + +u16 nvmet_ctrl_find_get(const char *subsysnqn, const char *hostnqn, u16 cntlid, + struct nvmet_req *req, struct nvmet_ctrl **ret) +{ + struct nvmet_subsys *subsys; + struct nvmet_ctrl *ctrl; + u16 status = 0; + + subsys = nvmet_find_get_subsys(req->port, subsysnqn); + if (!subsys) { + pr_warn("connect request for invalid subsystem %s!\n", + subsysnqn); + req->rsp->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn); + return NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR; + } + + mutex_lock(&subsys->lock); + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) { + if (ctrl->cntlid == cntlid) { + if (strncmp(hostnqn, ctrl->hostnqn, NVMF_NQN_SIZE)) { + pr_warn("hostnqn mismatch.\n"); + continue; + } + if (!kref_get_unless_zero(&ctrl->ref)) + continue; + + *ret = ctrl; + goto out; + } + } + + pr_warn("could not find controller %d for subsys %s / host %s\n", + cntlid, subsysnqn, hostnqn); + req->rsp->result.u32 = IPO_IATTR_CONNECT_DATA(cntlid); + status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR; + +out: + mutex_unlock(&subsys->lock); + nvmet_subsys_put(subsys); + return status; +} + +u16 nvmet_check_ctrl_status(struct nvmet_req *req, struct nvme_command *cmd) +{ + if (unlikely(!(req->sq->ctrl->cc & NVME_CC_ENABLE))) { + pr_err("got cmd %d while CC.EN == 0 on qid = %d\n", + cmd->common.opcode, req->sq->qid); + return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR; + } + + if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) { + pr_err("got cmd %d while CSTS.RDY == 0 on qid = %d\n", + cmd->common.opcode, req->sq->qid); + return NVME_SC_CMD_SEQ_ERROR | NVME_SC_DNR; + } + return 0; +} + +static bool __nvmet_host_allowed(struct nvmet_subsys *subsys, + const char *hostnqn) +{ + struct nvmet_host_link *p; + + if (subsys->allow_any_host) + return true; + + list_for_each_entry(p, &subsys->hosts, entry) { + if (!strcmp(nvmet_host_name(p->host), hostnqn)) + return true; + } + + return false; +} + +static bool nvmet_host_discovery_allowed(struct nvmet_req *req, + const char *hostnqn) +{ + struct nvmet_subsys_link *s; + + list_for_each_entry(s, &req->port->subsystems, entry) { + if (__nvmet_host_allowed(s->subsys, hostnqn)) + return true; + } + + return false; +} + +bool nvmet_host_allowed(struct nvmet_req *req, struct nvmet_subsys *subsys, + const char *hostnqn) +{ + lockdep_assert_held(&nvmet_config_sem); + + if (subsys->type == NVME_NQN_DISC) + return nvmet_host_discovery_allowed(req, hostnqn); + else + return __nvmet_host_allowed(subsys, hostnqn); +} + +static void nvmet_fatal_error_handler(struct work_struct *work) +{ + struct nvmet_ctrl *ctrl = + container_of(work, struct nvmet_ctrl, fatal_err_work); + + pr_err("ctrl %d fatal error occurred!\n", ctrl->cntlid); + ctrl->ops->delete_ctrl(ctrl); +} + +u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn, + struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp) +{ + struct nvmet_subsys *subsys; + struct nvmet_ctrl *ctrl; + int ret; + u16 status; + + status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR; + subsys = nvmet_find_get_subsys(req->port, subsysnqn); + if (!subsys) { + pr_warn("connect request for invalid subsystem %s!\n", + subsysnqn); + req->rsp->result.u32 = IPO_IATTR_CONNECT_DATA(subsysnqn); + goto out; + } + + status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR; + down_read(&nvmet_config_sem); + if (!nvmet_host_allowed(req, subsys, hostnqn)) { + pr_info("connect by host %s for subsystem %s not allowed\n", + hostnqn, subsysnqn); + req->rsp->result.u32 = IPO_IATTR_CONNECT_DATA(hostnqn); + up_read(&nvmet_config_sem); + status = NVME_SC_CONNECT_INVALID_HOST | NVME_SC_DNR; + goto out_put_subsystem; + } + up_read(&nvmet_config_sem); + + status = NVME_SC_INTERNAL; + ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL); + if (!ctrl) + goto out_put_subsystem; + mutex_init(&ctrl->lock); + + nvmet_init_cap(ctrl); + + ctrl->port = req->port; + + INIT_WORK(&ctrl->async_event_work, nvmet_async_event_work); + INIT_LIST_HEAD(&ctrl->async_events); + INIT_WORK(&ctrl->fatal_err_work, nvmet_fatal_error_handler); + + memcpy(ctrl->subsysnqn, subsysnqn, NVMF_NQN_SIZE); + memcpy(ctrl->hostnqn, hostnqn, NVMF_NQN_SIZE); + + kref_init(&ctrl->ref); + ctrl->subsys = subsys; + WRITE_ONCE(ctrl->aen_enabled, NVMET_AEN_CFG_OPTIONAL); + + ctrl->changed_ns_list = kmalloc_array(NVME_MAX_CHANGED_NAMESPACES, + sizeof(__le32), GFP_KERNEL); + if (!ctrl->changed_ns_list) + goto out_free_ctrl; + + ctrl->cqs = kcalloc(subsys->max_qid + 1, + sizeof(struct nvmet_cq *), + GFP_KERNEL); + if (!ctrl->cqs) + goto out_free_changed_ns_list; + + ctrl->sqs = kcalloc(subsys->max_qid + 1, + sizeof(struct nvmet_sq *), + GFP_KERNEL); + if (!ctrl->sqs) + goto out_free_cqs; + + ret = ida_simple_get(&cntlid_ida, + NVME_CNTLID_MIN, NVME_CNTLID_MAX, + GFP_KERNEL); + if (ret < 0) { + status = NVME_SC_CONNECT_CTRL_BUSY | NVME_SC_DNR; + goto out_free_sqs; + } + ctrl->cntlid = ret; + + ctrl->ops = req->ops; + if (ctrl->subsys->type == NVME_NQN_DISC) { + /* Don't accept keep-alive timeout for discovery controllers */ + if (kato) { + status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; + goto out_remove_ida; + } + + /* + * Discovery controllers use some arbitrary high value in order + * to cleanup stale discovery sessions + * + * From the latest base diff RC: + * "The Keep Alive command is not supported by + * Discovery controllers. A transport may specify a + * fixed Discovery controller activity timeout value + * (e.g., 2 minutes). If no commands are received + * by a Discovery controller within that time + * period, the controller may perform the + * actions for Keep Alive Timer expiration". + */ + ctrl->kato = NVMET_DISC_KATO; + } else { + /* keep-alive timeout in seconds */ + ctrl->kato = DIV_ROUND_UP(kato, 1000); + } + nvmet_start_keep_alive_timer(ctrl); + + mutex_lock(&subsys->lock); + list_add_tail(&ctrl->subsys_entry, &subsys->ctrls); + mutex_unlock(&subsys->lock); + + *ctrlp = ctrl; + return 0; + +out_remove_ida: + ida_simple_remove(&cntlid_ida, ctrl->cntlid); +out_free_sqs: + kfree(ctrl->sqs); +out_free_cqs: + kfree(ctrl->cqs); +out_free_changed_ns_list: + kfree(ctrl->changed_ns_list); +out_free_ctrl: + kfree(ctrl); +out_put_subsystem: + nvmet_subsys_put(subsys); +out: + return status; +} + +static void nvmet_ctrl_free(struct kref *ref) +{ + struct nvmet_ctrl *ctrl = container_of(ref, struct nvmet_ctrl, ref); + struct nvmet_subsys *subsys = ctrl->subsys; + + mutex_lock(&subsys->lock); + list_del(&ctrl->subsys_entry); + mutex_unlock(&subsys->lock); + + nvmet_stop_keep_alive_timer(ctrl); + + flush_work(&ctrl->async_event_work); + cancel_work_sync(&ctrl->fatal_err_work); + + ida_simple_remove(&cntlid_ida, ctrl->cntlid); + + kfree(ctrl->sqs); + kfree(ctrl->cqs); + kfree(ctrl->changed_ns_list); + kfree(ctrl); + + nvmet_subsys_put(subsys); +} + +void nvmet_ctrl_put(struct nvmet_ctrl *ctrl) +{ + kref_put(&ctrl->ref, nvmet_ctrl_free); +} + +void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl) +{ + mutex_lock(&ctrl->lock); + if (!(ctrl->csts & NVME_CSTS_CFS)) { + ctrl->csts |= NVME_CSTS_CFS; + schedule_work(&ctrl->fatal_err_work); + } + mutex_unlock(&ctrl->lock); +} +EXPORT_SYMBOL_GPL(nvmet_ctrl_fatal_error); + +static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port, + const char *subsysnqn) +{ + struct nvmet_subsys_link *p; + + if (!port) + return NULL; + + if (!strncmp(NVME_DISC_SUBSYS_NAME, subsysnqn, + NVMF_NQN_SIZE)) { + if (!kref_get_unless_zero(&nvmet_disc_subsys->ref)) + return NULL; + return nvmet_disc_subsys; + } + + down_read(&nvmet_config_sem); + list_for_each_entry(p, &port->subsystems, entry) { + if (!strncmp(p->subsys->subsysnqn, subsysnqn, + NVMF_NQN_SIZE)) { + if (!kref_get_unless_zero(&p->subsys->ref)) + break; + up_read(&nvmet_config_sem); + return p->subsys; + } + } + up_read(&nvmet_config_sem); + return NULL; +} + +struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn, + enum nvme_subsys_type type) +{ + struct nvmet_subsys *subsys; + + subsys = kzalloc(sizeof(*subsys), GFP_KERNEL); + if (!subsys) + return NULL; + + subsys->ver = NVME_VS(1, 3, 0); /* NVMe 1.3.0 */ + /* generate a random serial number as our controllers are ephemeral: */ + get_random_bytes(&subsys->serial, sizeof(subsys->serial)); + + switch (type) { + case NVME_NQN_NVME: + subsys->max_qid = NVMET_NR_QUEUES; + break; + case NVME_NQN_DISC: + subsys->max_qid = 0; + break; + default: + pr_err("%s: Unknown Subsystem type - %d\n", __func__, type); + kfree(subsys); + return NULL; + } + subsys->type = type; + subsys->subsysnqn = kstrndup(subsysnqn, NVMF_NQN_SIZE, + GFP_KERNEL); + if (!subsys->subsysnqn) { + kfree(subsys); + return NULL; + } + + kref_init(&subsys->ref); + + mutex_init(&subsys->lock); + INIT_LIST_HEAD(&subsys->namespaces); + INIT_LIST_HEAD(&subsys->ctrls); + INIT_LIST_HEAD(&subsys->hosts); + + return subsys; +} + +static void nvmet_subsys_free(struct kref *ref) +{ + struct nvmet_subsys *subsys = + container_of(ref, struct nvmet_subsys, ref); + + WARN_ON_ONCE(!list_empty(&subsys->namespaces)); + + kfree(subsys->subsysnqn); + kfree(subsys); +} + +void nvmet_subsys_del_ctrls(struct nvmet_subsys *subsys) +{ + struct nvmet_ctrl *ctrl; + + mutex_lock(&subsys->lock); + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) + ctrl->ops->delete_ctrl(ctrl); + mutex_unlock(&subsys->lock); +} + +void nvmet_subsys_put(struct nvmet_subsys *subsys) +{ + kref_put(&subsys->ref, nvmet_subsys_free); +} + +static int __init nvmet_init(void) +{ + int error; + + nvmet_ana_group_enabled[NVMET_DEFAULT_ANA_GRPID] = 1; + + buffered_io_wq = alloc_workqueue("nvmet-buffered-io-wq", + WQ_MEM_RECLAIM, 0); + if (!buffered_io_wq) { + error = -ENOMEM; + goto out; + } + + error = nvmet_init_discovery(); + if (error) + goto out_free_work_queue; + + error = nvmet_init_configfs(); + if (error) + goto out_exit_discovery; + return 0; + +out_exit_discovery: + nvmet_exit_discovery(); +out_free_work_queue: + destroy_workqueue(buffered_io_wq); +out: + return error; +} + +static void __exit nvmet_exit(void) +{ + nvmet_exit_configfs(); + nvmet_exit_discovery(); + ida_destroy(&cntlid_ida); + destroy_workqueue(buffered_io_wq); + + BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_entry) != 1024); + BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_hdr) != 1024); +} + +module_init(nvmet_init); +module_exit(nvmet_exit); + +MODULE_LICENSE("GPL v2"); |