// SPDX-License-Identifier: GPL-2.0-or-later /******************************************************************************* * Filename: target_core_transport.c * * This file contains the Generic Target Engine Core. * * (c) Copyright 2002-2013 Datera, Inc. * * Nicholas A. Bellinger * ******************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "target_core_internal.h" #include "target_core_alua.h" #include "target_core_pr.h" #include "target_core_ua.h" #define CREATE_TRACE_POINTS #include static struct workqueue_struct *target_completion_wq; static struct workqueue_struct *target_submission_wq; static struct kmem_cache *se_sess_cache; struct kmem_cache *se_ua_cache; struct kmem_cache *t10_pr_reg_cache; struct kmem_cache *t10_alua_lu_gp_cache; struct kmem_cache *t10_alua_lu_gp_mem_cache; struct kmem_cache *t10_alua_tg_pt_gp_cache; struct kmem_cache *t10_alua_lba_map_cache; struct kmem_cache *t10_alua_lba_map_mem_cache; static void transport_complete_task_attr(struct se_cmd *cmd); static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason); static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev, int err, bool write_pending); static void target_complete_ok_work(struct work_struct *work); int init_se_kmem_caches(void) { se_sess_cache = kmem_cache_create("se_sess_cache", sizeof(struct se_session), __alignof__(struct se_session), 0, NULL); if (!se_sess_cache) { pr_err("kmem_cache_create() for struct se_session" " failed\n"); goto out; } se_ua_cache = kmem_cache_create("se_ua_cache", sizeof(struct se_ua), __alignof__(struct se_ua), 0, NULL); if (!se_ua_cache) { pr_err("kmem_cache_create() for struct se_ua failed\n"); goto out_free_sess_cache; } t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache", sizeof(struct t10_pr_registration), __alignof__(struct t10_pr_registration), 0, NULL); if (!t10_pr_reg_cache) { pr_err("kmem_cache_create() for struct t10_pr_registration" " failed\n"); goto out_free_ua_cache; } t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache", sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp), 0, NULL); if (!t10_alua_lu_gp_cache) { pr_err("kmem_cache_create() for t10_alua_lu_gp_cache" " failed\n"); goto out_free_pr_reg_cache; } t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache", sizeof(struct t10_alua_lu_gp_member), __alignof__(struct t10_alua_lu_gp_member), 0, NULL); if (!t10_alua_lu_gp_mem_cache) { pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_" "cache failed\n"); goto out_free_lu_gp_cache; } t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache", sizeof(struct t10_alua_tg_pt_gp), __alignof__(struct t10_alua_tg_pt_gp), 0, NULL); if (!t10_alua_tg_pt_gp_cache) { pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_" "cache failed\n"); goto out_free_lu_gp_mem_cache; } t10_alua_lba_map_cache = kmem_cache_create( "t10_alua_lba_map_cache", sizeof(struct t10_alua_lba_map), __alignof__(struct t10_alua_lba_map), 0, NULL); if (!t10_alua_lba_map_cache) { pr_err("kmem_cache_create() for t10_alua_lba_map_" "cache failed\n"); goto out_free_tg_pt_gp_cache; } t10_alua_lba_map_mem_cache = kmem_cache_create( "t10_alua_lba_map_mem_cache", sizeof(struct t10_alua_lba_map_member), __alignof__(struct t10_alua_lba_map_member), 0, NULL); if (!t10_alua_lba_map_mem_cache) { pr_err("kmem_cache_create() for t10_alua_lba_map_mem_" "cache failed\n"); goto out_free_lba_map_cache; } target_completion_wq = alloc_workqueue("target_completion", WQ_MEM_RECLAIM, 0); if (!target_completion_wq) goto out_free_lba_map_mem_cache; target_submission_wq = alloc_workqueue("target_submission", WQ_MEM_RECLAIM, 0); if (!target_submission_wq) goto out_free_completion_wq; return 0; out_free_completion_wq: destroy_workqueue(target_completion_wq); out_free_lba_map_mem_cache: kmem_cache_destroy(t10_alua_lba_map_mem_cache); out_free_lba_map_cache: kmem_cache_destroy(t10_alua_lba_map_cache); out_free_tg_pt_gp_cache: kmem_cache_destroy(t10_alua_tg_pt_gp_cache); out_free_lu_gp_mem_cache: kmem_cache_destroy(t10_alua_lu_gp_mem_cache); out_free_lu_gp_cache: kmem_cache_destroy(t10_alua_lu_gp_cache); out_free_pr_reg_cache: kmem_cache_destroy(t10_pr_reg_cache); out_free_ua_cache: kmem_cache_destroy(se_ua_cache); out_free_sess_cache: kmem_cache_destroy(se_sess_cache); out: return -ENOMEM; } void release_se_kmem_caches(void) { destroy_workqueue(target_submission_wq); destroy_workqueue(target_completion_wq); kmem_cache_destroy(se_sess_cache); kmem_cache_destroy(se_ua_cache); kmem_cache_destroy(t10_pr_reg_cache); kmem_cache_destroy(t10_alua_lu_gp_cache); kmem_cache_destroy(t10_alua_lu_gp_mem_cache); kmem_cache_destroy(t10_alua_tg_pt_gp_cache); kmem_cache_destroy(t10_alua_lba_map_cache); kmem_cache_destroy(t10_alua_lba_map_mem_cache); } /* This code ensures unique mib indexes are handed out. */ static DEFINE_SPINLOCK(scsi_mib_index_lock); static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX]; /* * Allocate a new row index for the entry type specified */ u32 scsi_get_new_index(scsi_index_t type) { u32 new_index; BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX)); spin_lock(&scsi_mib_index_lock); new_index = ++scsi_mib_index[type]; spin_unlock(&scsi_mib_index_lock); return new_index; } void transport_subsystem_check_init(void) { int ret; static int sub_api_initialized; if (sub_api_initialized) return; ret = IS_ENABLED(CONFIG_TCM_IBLOCK) && request_module("target_core_iblock"); if (ret != 0) pr_err("Unable to load target_core_iblock\n"); ret = IS_ENABLED(CONFIG_TCM_FILEIO) && request_module("target_core_file"); if (ret != 0) pr_err("Unable to load target_core_file\n"); ret = IS_ENABLED(CONFIG_TCM_PSCSI) && request_module("target_core_pscsi"); if (ret != 0) pr_err("Unable to load target_core_pscsi\n"); ret = IS_ENABLED(CONFIG_TCM_USER2) && request_module("target_core_user"); if (ret != 0) pr_err("Unable to load target_core_user\n"); sub_api_initialized = 1; } static void target_release_cmd_refcnt(struct percpu_ref *ref) { struct target_cmd_counter *cmd_cnt = container_of(ref, typeof(*cmd_cnt), refcnt); wake_up(&cmd_cnt->refcnt_wq); } struct target_cmd_counter *target_alloc_cmd_counter(void) { struct target_cmd_counter *cmd_cnt; int rc; cmd_cnt = kzalloc(sizeof(*cmd_cnt), GFP_KERNEL); if (!cmd_cnt) return NULL; init_completion(&cmd_cnt->stop_done); init_waitqueue_head(&cmd_cnt->refcnt_wq); atomic_set(&cmd_cnt->stopped, 0); rc = percpu_ref_init(&cmd_cnt->refcnt, target_release_cmd_refcnt, 0, GFP_KERNEL); if (rc) goto free_cmd_cnt; return cmd_cnt; free_cmd_cnt: kfree(cmd_cnt); return NULL; } EXPORT_SYMBOL_GPL(target_alloc_cmd_counter); void target_free_cmd_counter(struct target_cmd_counter *cmd_cnt) { /* * Drivers like loop do not call target_stop_session during session * shutdown so we have to drop the ref taken at init time here. */ if (!atomic_read(&cmd_cnt->stopped)) percpu_ref_put(&cmd_cnt->refcnt); percpu_ref_exit(&cmd_cnt->refcnt); } EXPORT_SYMBOL_GPL(target_free_cmd_counter); /** * transport_init_session - initialize a session object * @se_sess: Session object pointer. * * The caller must have zero-initialized @se_sess before calling this function. */ void transport_init_session(struct se_session *se_sess) { INIT_LIST_HEAD(&se_sess->sess_list); INIT_LIST_HEAD(&se_sess->sess_acl_list); spin_lock_init(&se_sess->sess_cmd_lock); } EXPORT_SYMBOL(transport_init_session); /** * transport_alloc_session - allocate a session object and initialize it * @sup_prot_ops: bitmask that defines which T10-PI modes are supported. */ struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops) { struct se_session *se_sess; se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL); if (!se_sess) { pr_err("Unable to allocate struct se_session from" " se_sess_cache\n"); return ERR_PTR(-ENOMEM); } transport_init_session(se_sess); se_sess->sup_prot_ops = sup_prot_ops; return se_sess; } EXPORT_SYMBOL(transport_alloc_session); /** * transport_alloc_session_tags - allocate target driver private data * @se_sess: Session pointer. * @tag_num: Maximum number of in-flight commands between initiator and target. * @tag_size: Size in bytes of the private data a target driver associates with * each command. */ int transport_alloc_session_tags(struct se_session *se_sess, unsigned int tag_num, unsigned int tag_size) { int rc; se_sess->sess_cmd_map = kvcalloc(tag_size, tag_num, GFP_KERNEL | __GFP_RETRY_MAYFAIL); if (!se_sess->sess_cmd_map) { pr_err("Unable to allocate se_sess->sess_cmd_map\n"); return -ENOMEM; } rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1, false, GFP_KERNEL, NUMA_NO_NODE); if (rc < 0) { pr_err("Unable to init se_sess->sess_tag_pool," " tag_num: %u\n", tag_num); kvfree(se_sess->sess_cmd_map); se_sess->sess_cmd_map = NULL; return -ENOMEM; } return 0; } EXPORT_SYMBOL(transport_alloc_session_tags); /** * transport_init_session_tags - allocate a session and target driver private data * @tag_num: Maximum number of in-flight commands between initiator and target. * @tag_size: Size in bytes of the private data a target driver associates with * each command. * @sup_prot_ops: bitmask that defines which T10-PI modes are supported. */ static struct se_session * transport_init_session_tags(unsigned int tag_num, unsigned int tag_size, enum target_prot_op sup_prot_ops) { struct se_session *se_sess; int rc; if (tag_num != 0 && !tag_size) { pr_err("init_session_tags called with percpu-ida tag_num:" " %u, but zero tag_size\n", tag_num); return ERR_PTR(-EINVAL); } if (!tag_num && tag_size) { pr_err("init_session_tags called with percpu-ida tag_size:" " %u, but zero tag_num\n", tag_size); return ERR_PTR(-EINVAL); } se_sess = transport_alloc_session(sup_prot_ops); if (IS_ERR(se_sess)) return se_sess; rc = transport_alloc_session_tags(se_sess, tag_num, tag_size); if (rc < 0) { transport_free_session(se_sess); return ERR_PTR(-ENOMEM); } return se_sess; } /* * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called. */ void __transport_register_session( struct se_portal_group *se_tpg, struct se_node_acl *se_nacl, struct se_session *se_sess, void *fabric_sess_ptr) { const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo; unsigned char buf[PR_REG_ISID_LEN]; unsigned long flags; se_sess->se_tpg = se_tpg; se_sess->fabric_sess_ptr = fabric_sess_ptr; /* * Used by struct se_node_acl's under ConfigFS to locate active se_session-t * * Only set for struct se_session's that will actually be moving I/O. * eg: *NOT* discovery sessions. */ if (se_nacl) { /* * * Determine if fabric allows for T10-PI feature bits exposed to * initiators for device backends with !dev->dev_attrib.pi_prot_type. * * If so, then always save prot_type on a per se_node_acl node * basis and re-instate the previous sess_prot_type to avoid * disabling PI from below any previously initiator side * registered LUNs. */ if (se_nacl->saved_prot_type) se_sess->sess_prot_type = se_nacl->saved_prot_type; else if (tfo->tpg_check_prot_fabric_only) se_sess->sess_prot_type = se_nacl->saved_prot_type = tfo->tpg_check_prot_fabric_only(se_tpg); /* * If the fabric module supports an ISID based TransportID, * save this value in binary from the fabric I_T Nexus now. */ if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) { memset(&buf[0], 0, PR_REG_ISID_LEN); se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &buf[0], PR_REG_ISID_LEN); se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]); } spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags); /* * The se_nacl->nacl_sess pointer will be set to the * last active I_T Nexus for each struct se_node_acl. */ se_nacl->nacl_sess = se_sess; list_add_tail(&se_sess->sess_acl_list, &se_nacl->acl_sess_list); spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags); } list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list); pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n", se_tpg->se_tpg_tfo->fabric_name, se_sess->fabric_sess_ptr); } EXPORT_SYMBOL(__transport_register_session); void transport_register_session( struct se_portal_group *se_tpg, struct se_node_acl *se_nacl, struct se_session *se_sess, void *fabric_sess_ptr) { unsigned long flags; spin_lock_irqsave(&se_tpg->session_lock, flags); __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr); spin_unlock_irqrestore(&se_tpg->session_lock, flags); } EXPORT_SYMBOL(transport_register_session); struct se_session * target_setup_session(struct se_portal_group *tpg, unsigned int tag_num, unsigned int tag_size, enum target_prot_op prot_op, const char *initiatorname, void *private, int (*callback)(struct se_portal_group *, struct se_session *, void *)) { struct target_cmd_counter *cmd_cnt; struct se_session *sess; int rc; cmd_cnt = target_alloc_cmd_counter(); if (!cmd_cnt) return ERR_PTR(-ENOMEM); /* * If the fabric driver is using percpu-ida based pre allocation * of I/O descriptor tags, go ahead and perform that setup now.. */ if (tag_num != 0) sess = transport_init_session_tags(tag_num, tag_size, prot_op); else sess = transport_alloc_session(prot_op); if (IS_ERR(sess)) { rc = PTR_ERR(sess); goto free_cnt; } sess->cmd_cnt = cmd_cnt; sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg, (unsigned char *)initiatorname); if (!sess->se_node_acl) { rc = -EACCES; goto free_sess; } /* * Go ahead and perform any remaining fabric setup that is * required before transport_register_session(). */ if (callback != NULL) { rc = callback(tpg, sess, private); if (rc) goto free_sess; } transport_register_session(tpg, sess->se_node_acl, sess, private); return sess; free_sess: transport_free_session(sess); return ERR_PTR(rc); free_cnt: target_free_cmd_counter(cmd_cnt); return ERR_PTR(rc); } EXPORT_SYMBOL(target_setup_session); ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page) { struct se_session *se_sess; ssize_t len = 0; spin_lock_bh(&se_tpg->session_lock); list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) { if (!se_sess->se_node_acl) continue; if (!se_sess->se_node_acl->dynamic_node_acl) continue; if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE) break; len += snprintf(page + len, PAGE_SIZE - len, "%s\n", se_sess->se_node_acl->initiatorname); len += 1; /* Include NULL terminator */ } spin_unlock_bh(&se_tpg->session_lock); return len; } EXPORT_SYMBOL(target_show_dynamic_sessions); static void target_complete_nacl(struct kref *kref) { struct se_node_acl *nacl = container_of(kref, struct se_node_acl, acl_kref); struct se_portal_group *se_tpg = nacl->se_tpg; if (!nacl->dynamic_stop) { complete(&nacl->acl_free_comp); return; } mutex_lock(&se_tpg->acl_node_mutex); list_del_init(&nacl->acl_list); mutex_unlock(&se_tpg->acl_node_mutex); core_tpg_wait_for_nacl_pr_ref(nacl); core_free_device_list_for_node(nacl, se_tpg); kfree(nacl); } void target_put_nacl(struct se_node_acl *nacl) { kref_put(&nacl->acl_kref, target_complete_nacl); } EXPORT_SYMBOL(target_put_nacl); void transport_deregister_session_configfs(struct se_session *se_sess) { struct se_node_acl *se_nacl; unsigned long flags; /* * Used by struct se_node_acl's under ConfigFS to locate active struct se_session */ se_nacl = se_sess->se_node_acl; if (se_nacl) { spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags); if (!list_empty(&se_sess->sess_acl_list)) list_del_init(&se_sess->sess_acl_list); /* * If the session list is empty, then clear the pointer. * Otherwise, set the struct se_session pointer from the tail * element of the per struct se_node_acl active session list. */ if (list_empty(&se_nacl->acl_sess_list)) se_nacl->nacl_sess = NULL; else { se_nacl->nacl_sess = container_of( se_nacl->acl_sess_list.prev, struct se_session, sess_acl_list); } spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags); } } EXPORT_SYMBOL(transport_deregister_session_configfs); void transport_free_session(struct se_session *se_sess) { struct se_node_acl *se_nacl = se_sess->se_node_acl; /* * Drop the se_node_acl->nacl_kref obtained from within * core_tpg_get_initiator_node_acl(). */ if (se_nacl) { struct se_portal_group *se_tpg = se_nacl->se_tpg; const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo; unsigned long flags; se_sess->se_node_acl = NULL; /* * Also determine if we need to drop the extra ->cmd_kref if * it had been previously dynamically generated, and * the endpoint is not caching dynamic ACLs. */ mutex_lock(&se_tpg->acl_node_mutex); if (se_nacl->dynamic_node_acl && !se_tfo->tpg_check_demo_mode_cache(se_tpg)) { spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags); if (list_empty(&se_nacl->acl_sess_list)) se_nacl->dynamic_stop = true; spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags); if (se_nacl->dynamic_stop) list_del_init(&se_nacl->acl_list); } mutex_unlock(&se_tpg->acl_node_mutex); if (se_nacl->dynamic_stop) target_put_nacl(se_nacl); target_put_nacl(se_nacl); } if (se_sess->sess_cmd_map) { sbitmap_queue_free(&se_sess->sess_tag_pool); kvfree(se_sess->sess_cmd_map); } if (se_sess->cmd_cnt) target_free_cmd_counter(se_sess->cmd_cnt); kmem_cache_free(se_sess_cache, se_sess); } EXPORT_SYMBOL(transport_free_session); static int target_release_res(struct se_device *dev, void *data) { struct se_session *sess = data; if (dev->reservation_holder == sess) target_release_reservation(dev); return 0; } void transport_deregister_session(struct se_session *se_sess) { struct se_portal_group *se_tpg = se_sess->se_tpg; unsigned long flags; if (!se_tpg) { transport_free_session(se_sess); return; } spin_lock_irqsave(&se_tpg->session_lock, flags); list_del(&se_sess->sess_list); se_sess->se_tpg = NULL; se_sess->fabric_sess_ptr = NULL; spin_unlock_irqrestore(&se_tpg->session_lock, flags); /* * Since the session is being removed, release SPC-2 * reservations held by the session that is disappearing. */ target_for_each_device(target_release_res, se_sess); pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n", se_tpg->se_tpg_tfo->fabric_name); /* * If last kref is dropping now for an explicit NodeACL, awake sleeping * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group * removal context from within transport_free_session() code. * * For dynamic ACL, target_put_nacl() uses target_complete_nacl() * to release all remaining generate_node_acl=1 created ACL resources. */ transport_free_session(se_sess); } EXPORT_SYMBOL(transport_deregister_session); void target_remove_session(struct se_session *se_sess) { transport_deregister_session_configfs(se_sess); transport_deregister_session(se_sess); } EXPORT_SYMBOL(target_remove_session); static void target_remove_from_state_list(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; unsigned long flags; if (!dev) return; spin_lock_irqsave(&dev->queues[cmd->cpuid].lock, flags); if (cmd->state_active) { list_del(&cmd->state_list); cmd->state_active = false; } spin_unlock_irqrestore(&dev->queues[cmd->cpuid].lock, flags); } static void target_remove_from_tmr_list(struct se_cmd *cmd) { struct se_device *dev = NULL; unsigned long flags; if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) dev = cmd->se_tmr_req->tmr_dev; if (dev) { spin_lock_irqsave(&dev->se_tmr_lock, flags); if (cmd->se_tmr_req->tmr_dev) list_del_init(&cmd->se_tmr_req->tmr_list); spin_unlock_irqrestore(&dev->se_tmr_lock, flags); } } /* * This function is called by the target core after the target core has * finished processing a SCSI command or SCSI TMF. Both the regular command * processing code and the code for aborting commands can call this * function. CMD_T_STOP is set if and only if another thread is waiting * inside transport_wait_for_tasks() for t_transport_stop_comp. */ static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd) { unsigned long flags; spin_lock_irqsave(&cmd->t_state_lock, flags); /* * Determine if frontend context caller is requesting the stopping of * this command for frontend exceptions. */ if (cmd->transport_state & CMD_T_STOP) { pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n", __func__, __LINE__, cmd->tag); spin_unlock_irqrestore(&cmd->t_state_lock, flags); complete_all(&cmd->t_transport_stop_comp); return 1; } cmd->transport_state &= ~CMD_T_ACTIVE; spin_unlock_irqrestore(&cmd->t_state_lock, flags); /* * Some fabric modules like tcm_loop can release their internally * allocated I/O reference and struct se_cmd now. * * Fabric modules are expected to return '1' here if the se_cmd being * passed is released at this point, or zero if not being released. */ return cmd->se_tfo->check_stop_free(cmd); } static void transport_lun_remove_cmd(struct se_cmd *cmd) { struct se_lun *lun = cmd->se_lun; if (!lun) return; target_remove_from_state_list(cmd); target_remove_from_tmr_list(cmd); if (cmpxchg(&cmd->lun_ref_active, true, false)) percpu_ref_put(&lun->lun_ref); /* * Clear struct se_cmd->se_lun before the handoff to FE. */ cmd->se_lun = NULL; } static void target_complete_failure_work(struct work_struct *work) { struct se_cmd *cmd = container_of(work, struct se_cmd, work); transport_generic_request_failure(cmd, cmd->sense_reason); } /* * Used when asking transport to copy Sense Data from the underlying * Linux/SCSI struct scsi_cmnd */ static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; WARN_ON(!cmd->se_lun); if (!dev) return NULL; if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) return NULL; cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER; pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n", dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status); return cmd->sense_buffer; } void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense) { unsigned char *cmd_sense_buf; unsigned long flags; spin_lock_irqsave(&cmd->t_state_lock, flags); cmd_sense_buf = transport_get_sense_buffer(cmd); if (!cmd_sense_buf) { spin_unlock_irqrestore(&cmd->t_state_lock, flags); return; } cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE; memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length); spin_unlock_irqrestore(&cmd->t_state_lock, flags); } EXPORT_SYMBOL(transport_copy_sense_to_cmd); static void target_handle_abort(struct se_cmd *cmd) { bool tas = cmd->transport_state & CMD_T_TAS; bool ack_kref = cmd->se_cmd_flags & SCF_ACK_KREF; int ret; pr_debug("tag %#llx: send_abort_response = %d\n", cmd->tag, tas); if (tas) { if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) { cmd->scsi_status = SAM_STAT_TASK_ABORTED; pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag); trace_target_cmd_complete(cmd); ret = cmd->se_tfo->queue_status(cmd); if (ret) { transport_handle_queue_full(cmd, cmd->se_dev, ret, false); return; } } else { cmd->se_tmr_req->response = TMR_FUNCTION_REJECTED; cmd->se_tfo->queue_tm_rsp(cmd); } } else { /* * Allow the fabric driver to unmap any resources before * releasing the descriptor via TFO->release_cmd(). */ cmd->se_tfo->aborted_task(cmd); if (ack_kref) WARN_ON_ONCE(target_put_sess_cmd(cmd) != 0); /* * To do: establish a unit attention condition on the I_T * nexus associated with cmd. See also the paragraph "Aborting * commands" in SAM. */ } WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0); transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); } static void target_abort_work(struct work_struct *work) { struct se_cmd *cmd = container_of(work, struct se_cmd, work); target_handle_abort(cmd); } static bool target_cmd_interrupted(struct se_cmd *cmd) { int post_ret; if (cmd->transport_state & CMD_T_ABORTED) { if (cmd->transport_complete_callback) cmd->transport_complete_callback(cmd, false, &post_ret); INIT_WORK(&cmd->work, target_abort_work); queue_work(target_completion_wq, &cmd->work); return true; } else if (cmd->transport_state & CMD_T_STOP) { if (cmd->transport_complete_callback) cmd->transport_complete_callback(cmd, false, &post_ret); complete_all(&cmd->t_transport_stop_comp); return true; } return false; } /* May be called from interrupt context so must not sleep. */ void target_complete_cmd_with_sense(struct se_cmd *cmd, u8 scsi_status, sense_reason_t sense_reason) { struct se_wwn *wwn = cmd->se_sess->se_tpg->se_tpg_wwn; int success, cpu; unsigned long flags; if (target_cmd_interrupted(cmd)) return; cmd->scsi_status = scsi_status; cmd->sense_reason = sense_reason; spin_lock_irqsave(&cmd->t_state_lock, flags); switch (cmd->scsi_status) { case SAM_STAT_CHECK_CONDITION: if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) success = 1; else success = 0; break; default: success = 1; break; } cmd->t_state = TRANSPORT_COMPLETE; cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE); spin_unlock_irqrestore(&cmd->t_state_lock, flags); INIT_WORK(&cmd->work, success ? target_complete_ok_work : target_complete_failure_work); if (!wwn || wwn->cmd_compl_affinity == SE_COMPL_AFFINITY_CPUID) cpu = cmd->cpuid; else cpu = wwn->cmd_compl_affinity; queue_work_on(cpu, target_completion_wq, &cmd->work); } EXPORT_SYMBOL(target_complete_cmd_with_sense); void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status) { target_complete_cmd_with_sense(cmd, scsi_status, scsi_status ? TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE : TCM_NO_SENSE); } EXPORT_SYMBOL(target_complete_cmd); void target_set_cmd_data_length(struct se_cmd *cmd, int length) { if (length < cmd->data_length) { if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) { cmd->residual_count += cmd->data_length - length; } else { cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT; cmd->residual_count = cmd->data_length - length; } cmd->data_length = length; } } EXPORT_SYMBOL(target_set_cmd_data_length); void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length) { if (scsi_status == SAM_STAT_GOOD || cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) { target_set_cmd_data_length(cmd, length); } target_complete_cmd(cmd, scsi_status); } EXPORT_SYMBOL(target_complete_cmd_with_length); static void target_add_to_state_list(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; unsigned long flags; spin_lock_irqsave(&dev->queues[cmd->cpuid].lock, flags); if (!cmd->state_active) { list_add_tail(&cmd->state_list, &dev->queues[cmd->cpuid].state_list); cmd->state_active = true; } spin_unlock_irqrestore(&dev->queues[cmd->cpuid].lock, flags); } /* * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status */ static void transport_write_pending_qf(struct se_cmd *cmd); static void transport_complete_qf(struct se_cmd *cmd); void target_qf_do_work(struct work_struct *work) { struct se_device *dev = container_of(work, struct se_device, qf_work_queue); LIST_HEAD(qf_cmd_list); struct se_cmd *cmd, *cmd_tmp; spin_lock_irq(&dev->qf_cmd_lock); list_splice_init(&dev->qf_cmd_list, &qf_cmd_list); spin_unlock_irq(&dev->qf_cmd_lock); list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) { list_del(&cmd->se_qf_node); atomic_dec_mb(&dev->dev_qf_count); pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue" " context: %s\n", cmd->se_tfo->fabric_name, cmd, (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" : (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING" : "UNKNOWN"); if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) transport_write_pending_qf(cmd); else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK || cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) transport_complete_qf(cmd); } } unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd) { switch (cmd->data_direction) { case DMA_NONE: return "NONE"; case DMA_FROM_DEVICE: return "READ"; case DMA_TO_DEVICE: return "WRITE"; case DMA_BIDIRECTIONAL: return "BIDI"; default: break; } return "UNKNOWN"; } void transport_dump_dev_state( struct se_device *dev, char *b, int *bl) { *bl += sprintf(b + *bl, "Status: "); if (dev->export_count) *bl += sprintf(b + *bl, "ACTIVATED"); else *bl += sprintf(b + *bl, "DEACTIVATED"); *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth); *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n", dev->dev_attrib.block_size, dev->dev_attrib.hw_max_sectors); *bl += sprintf(b + *bl, " "); } void transport_dump_vpd_proto_id( struct t10_vpd *vpd, unsigned char *p_buf, int p_buf_len) { unsigned char buf[VPD_TMP_BUF_SIZE]; int len; memset(buf, 0, VPD_TMP_BUF_SIZE); len = sprintf(buf, "T10 VPD Protocol Identifier: "); switch (vpd->protocol_identifier) { case 0x00: sprintf(buf+len, "Fibre Channel\n"); break; case 0x10: sprintf(buf+len, "Parallel SCSI\n"); break; case 0x20: sprintf(buf+len, "SSA\n"); break; case 0x30: sprintf(buf+len, "IEEE 1394\n"); break; case 0x40: sprintf(buf+len, "SCSI Remote Direct Memory Access" " Protocol\n"); break; case 0x50: sprintf(buf+len, "Internet SCSI (iSCSI)\n"); break; case 0x60: sprintf(buf+len, "SAS Serial SCSI Protocol\n"); break; case 0x70: sprintf(buf+len, "Automation/Drive Interface Transport" " Protocol\n"); break; case 0x80: sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n"); break; default: sprintf(buf+len, "Unknown 0x%02x\n", vpd->protocol_identifier); break; } if (p_buf) strncpy(p_buf, buf, p_buf_len); else pr_debug("%s", buf); } void transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83) { /* * Check if the Protocol Identifier Valid (PIV) bit is set.. * * from spc3r23.pdf section 7.5.1 */ if (page_83[1] & 0x80) { vpd->protocol_identifier = (page_83[0] & 0xf0); vpd->protocol_identifier_set = 1; transport_dump_vpd_proto_id(vpd, NULL, 0); } } EXPORT_SYMBOL(transport_set_vpd_proto_id); int transport_dump_vpd_assoc( struct t10_vpd *vpd, unsigned char *p_buf, int p_buf_len) { unsigned char buf[VPD_TMP_BUF_SIZE]; int ret = 0; int len; memset(buf, 0, VPD_TMP_BUF_SIZE); len = sprintf(buf, "T10 VPD Identifier Association: "); switch (vpd->association) { case 0x00: sprintf(buf+len, "addressed logical unit\n"); break; case 0x10: sprintf(buf+len, "target port\n"); break; case 0x20: sprintf(buf+len, "SCSI target device\n"); break; default: sprintf(buf+len, "Unknown 0x%02x\n", vpd->association); ret = -EINVAL; break; } if (p_buf) strncpy(p_buf, buf, p_buf_len); else pr_debug("%s", buf); return ret; } int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83) { /* * The VPD identification association.. * * from spc3r23.pdf Section 7.6.3.1 Table 297 */ vpd->association = (page_83[1] & 0x30); return transport_dump_vpd_assoc(vpd, NULL, 0); } EXPORT_SYMBOL(transport_set_vpd_assoc); int transport_dump_vpd_ident_type( struct t10_vpd *vpd, unsigned char *p_buf, int p_buf_len) { unsigned char buf[VPD_TMP_BUF_SIZE]; int ret = 0; int len; memset(buf, 0, VPD_TMP_BUF_SIZE); len = sprintf(buf, "T10 VPD Identifier Type: "); switch (vpd->device_identifier_type) { case 0x00: sprintf(buf+len, "Vendor specific\n"); break; case 0x01: sprintf(buf+len, "T10 Vendor ID based\n"); break; case 0x02: sprintf(buf+len, "EUI-64 based\n"); break; case 0x03: sprintf(buf+len, "NAA\n"); break; case 0x04: sprintf(buf+len, "Relative target port identifier\n"); break; case 0x08: sprintf(buf+len, "SCSI name string\n"); break; default: sprintf(buf+len, "Unsupported: 0x%02x\n", vpd->device_identifier_type); ret = -EINVAL; break; } if (p_buf) { if (p_buf_len < strlen(buf)+1) return -EINVAL; strncpy(p_buf, buf, p_buf_len); } else { pr_debug("%s", buf); } return ret; } int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83) { /* * The VPD identifier type.. * * from spc3r23.pdf Section 7.6.3.1 Table 298 */ vpd->device_identifier_type = (page_83[1] & 0x0f); return transport_dump_vpd_ident_type(vpd, NULL, 0); } EXPORT_SYMBOL(transport_set_vpd_ident_type); int transport_dump_vpd_ident( struct t10_vpd *vpd, unsigned char *p_buf, int p_buf_len) { unsigned char buf[VPD_TMP_BUF_SIZE]; int ret = 0; memset(buf, 0, VPD_TMP_BUF_SIZE); switch (vpd->device_identifier_code_set) { case 0x01: /* Binary */ snprintf(buf, sizeof(buf), "T10 VPD Binary Device Identifier: %s\n", &vpd->device_identifier[0]); break; case 0x02: /* ASCII */ snprintf(buf, sizeof(buf), "T10 VPD ASCII Device Identifier: %s\n", &vpd->device_identifier[0]); break; case 0x03: /* UTF-8 */ snprintf(buf, sizeof(buf), "T10 VPD UTF-8 Device Identifier: %s\n", &vpd->device_identifier[0]); break; default: sprintf(buf, "T10 VPD Device Identifier encoding unsupported:" " 0x%02x", vpd->device_identifier_code_set); ret = -EINVAL; break; } if (p_buf) strncpy(p_buf, buf, p_buf_len); else pr_debug("%s", buf); return ret; } int transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83) { static const char hex_str[] = "0123456789abcdef"; int j = 0, i = 4; /* offset to start of the identifier */ /* * The VPD Code Set (encoding) * * from spc3r23.pdf Section 7.6.3.1 Table 296 */ vpd->device_identifier_code_set = (page_83[0] & 0x0f); switch (vpd->device_identifier_code_set) { case 0x01: /* Binary */ vpd->device_identifier[j++] = hex_str[vpd->device_identifier_type]; while (i < (4 + page_83[3])) { vpd->device_identifier[j++] = hex_str[(page_83[i] & 0xf0) >> 4]; vpd->device_identifier[j++] = hex_str[page_83[i] & 0x0f]; i++; } break; case 0x02: /* ASCII */ case 0x03: /* UTF-8 */ while (i < (4 + page_83[3])) vpd->device_identifier[j++] = page_83[i++]; break; default: break; } return transport_dump_vpd_ident(vpd, NULL, 0); } EXPORT_SYMBOL(transport_set_vpd_ident); static sense_reason_t target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev, unsigned int size) { u32 mtl; if (!cmd->se_tfo->max_data_sg_nents) return TCM_NO_SENSE; /* * Check if fabric enforced maximum SGL entries per I/O descriptor * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT + * residual_count and reduce original cmd->data_length to maximum * length based on single PAGE_SIZE entry scatter-lists. */ mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE); if (cmd->data_length > mtl) { /* * If an existing CDB overflow is present, calculate new residual * based on CDB size minus fabric maximum transfer length. * * If an existing CDB underflow is present, calculate new residual * based on original cmd->data_length minus fabric maximum transfer * length. * * Otherwise, set the underflow residual based on cmd->data_length * minus fabric maximum transfer length. */ if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) { cmd->residual_count = (size - mtl); } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) { u32 orig_dl = size + cmd->residual_count; cmd->residual_count = (orig_dl - mtl); } else { cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT; cmd->residual_count = (cmd->data_length - mtl); } cmd->data_length = mtl; /* * Reset sbc_check_prot() calculated protection payload * length based upon the new smaller MTL. */ if (cmd->prot_length) { u32 sectors = (mtl / dev->dev_attrib.block_size); cmd->prot_length = dev->prot_length * sectors; } } return TCM_NO_SENSE; } /** * target_cmd_size_check - Check whether there will be a residual. * @cmd: SCSI command. * @size: Data buffer size derived from CDB. The data buffer size provided by * the SCSI transport driver is available in @cmd->data_length. * * Compare the data buffer size from the CDB with the data buffer limit from the transport * header. Set @cmd->residual_count and SCF_OVERFLOW_BIT or SCF_UNDERFLOW_BIT if necessary. * * Note: target drivers set @cmd->data_length by calling __target_init_cmd(). * * Return: TCM_NO_SENSE */ sense_reason_t target_cmd_size_check(struct se_cmd *cmd, unsigned int size) { struct se_device *dev = cmd->se_dev; if (cmd->unknown_data_length) { cmd->data_length = size; } else if (size != cmd->data_length) { pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:" " %u does not match SCSI CDB Length: %u for SAM Opcode:" " 0x%02x\n", cmd->se_tfo->fabric_name, cmd->data_length, size, cmd->t_task_cdb[0]); /* * For READ command for the overflow case keep the existing * fabric provided ->data_length. Otherwise for the underflow * case, reset ->data_length to the smaller SCSI expected data * transfer length. */ if (size > cmd->data_length) { cmd->se_cmd_flags |= SCF_OVERFLOW_BIT; cmd->residual_count = (size - cmd->data_length); } else { cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT; cmd->residual_count = (cmd->data_length - size); /* * Do not truncate ->data_length for WRITE command to * dump all payload */ if (cmd->data_direction == DMA_FROM_DEVICE) { cmd->data_length = size; } } if (cmd->data_direction == DMA_TO_DEVICE) { if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) { pr_err_ratelimited("Rejecting underflow/overflow" " for WRITE data CDB\n"); return TCM_INVALID_FIELD_IN_COMMAND_IU; } /* * Some fabric drivers like iscsi-target still expect to * always reject overflow writes. Reject this case until * full fabric driver level support for overflow writes * is introduced tree-wide. */ if (size > cmd->data_length) { pr_err_ratelimited("Rejecting overflow for" " WRITE control CDB\n"); return TCM_INVALID_CDB_FIELD; } } } return target_check_max_data_sg_nents(cmd, dev, size); } /* * Used by fabric modules containing a local struct se_cmd within their * fabric dependent per I/O descriptor. * * Preserves the value of @cmd->tag. */ void __target_init_cmd(struct se_cmd *cmd, const struct target_core_fabric_ops *tfo, struct se_session *se_sess, u32 data_length, int data_direction, int task_attr, unsigned char *sense_buffer, u64 unpacked_lun, struct target_cmd_counter *cmd_cnt) { INIT_LIST_HEAD(&cmd->se_delayed_node); INIT_LIST_HEAD(&cmd->se_qf_node); INIT_LIST_HEAD(&cmd->state_list); init_completion(&cmd->t_transport_stop_comp); cmd->free_compl = NULL; cmd->abrt_compl = NULL; spin_lock_init(&cmd->t_state_lock); INIT_WORK(&cmd->work, NULL); kref_init(&cmd->cmd_kref); cmd->t_task_cdb = &cmd->__t_task_cdb[0]; cmd->se_tfo = tfo; cmd->se_sess = se_sess; cmd->data_length = data_length; cmd->data_direction = data_direction; cmd->sam_task_attr = task_attr; cmd->sense_buffer = sense_buffer; cmd->orig_fe_lun = unpacked_lun; cmd->cmd_cnt = cmd_cnt; if (!(cmd->se_cmd_flags & SCF_USE_CPUID)) cmd->cpuid = raw_smp_processor_id(); cmd->state_active = false; } EXPORT_SYMBOL(__target_init_cmd); static sense_reason_t transport_check_alloc_task_attr(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; /* * Check if SAM Task Attribute emulation is enabled for this * struct se_device storage object */ if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH) return 0; if (cmd->sam_task_attr == TCM_ACA_TAG) { pr_debug("SAM Task Attribute ACA" " emulation is not supported\n"); return TCM_INVALID_CDB_FIELD; } return 0; } sense_reason_t target_cmd_init_cdb(struct se_cmd *cmd, unsigned char *cdb, gfp_t gfp) { sense_reason_t ret; /* * Ensure that the received CDB is less than the max (252 + 8) bytes * for VARIABLE_LENGTH_CMD */ if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) { pr_err("Received SCSI CDB with command_size: %d that" " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n", scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE); ret = TCM_INVALID_CDB_FIELD; goto err; } /* * If the received CDB is larger than TCM_MAX_COMMAND_SIZE, * allocate the additional extended CDB buffer now.. Otherwise * setup the pointer from __t_task_cdb to t_task_cdb. */ if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) { cmd->t_task_cdb = kzalloc(scsi_command_size(cdb), gfp); if (!cmd->t_task_cdb) { pr_err("Unable to allocate cmd->t_task_cdb" " %u > sizeof(cmd->__t_task_cdb): %lu ops\n", scsi_command_size(cdb), (unsigned long)sizeof(cmd->__t_task_cdb)); ret = TCM_OUT_OF_RESOURCES; goto err; } } /* * Copy the original CDB into cmd-> */ memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb)); trace_target_sequencer_start(cmd); return 0; err: /* * Copy the CDB here to allow trace_target_cmd_complete() to * print the cdb to the trace buffers. */ memcpy(cmd->t_task_cdb, cdb, min(scsi_command_size(cdb), (unsigned int)TCM_MAX_COMMAND_SIZE)); return ret; } EXPORT_SYMBOL(target_cmd_init_cdb); sense_reason_t target_cmd_parse_cdb(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; sense_reason_t ret; ret = dev->transport->parse_cdb(cmd); if (ret == TCM_UNSUPPORTED_SCSI_OPCODE) pr_debug_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n", cmd->se_tfo->fabric_name, cmd->se_sess->se_node_acl->initiatorname, cmd->t_task_cdb[0]); if (ret) return ret; ret = transport_check_alloc_task_attr(cmd); if (ret) return ret; cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE; atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus); return 0; } EXPORT_SYMBOL(target_cmd_parse_cdb); /* * Used by fabric module frontends to queue tasks directly. * May only be used from process context. */ int transport_handle_cdb_direct( struct se_cmd *cmd) { sense_reason_t ret; might_sleep(); if (!cmd->se_lun) { dump_stack(); pr_err("cmd->se_lun is NULL\n"); return -EINVAL; } /* * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that * outstanding descriptors are handled correctly during shutdown via * transport_wait_for_tasks() * * Also, we don't take cmd->t_state_lock here as we only expect * this to be called for initial descriptor submission. */ cmd->t_state = TRANSPORT_NEW_CMD; cmd->transport_state |= CMD_T_ACTIVE; /* * transport_generic_new_cmd() is already handling QUEUE_FULL, * so follow TRANSPORT_NEW_CMD processing thread context usage * and call transport_generic_request_failure() if necessary.. */ ret = transport_generic_new_cmd(cmd); if (ret) transport_generic_request_failure(cmd, ret); return 0; } EXPORT_SYMBOL(transport_handle_cdb_direct); sense_reason_t transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count) { if (!sgl || !sgl_count) return 0; /* * Reject SCSI data overflow with map_mem_to_cmd() as incoming * scatterlists already have been set to follow what the fabric * passes for the original expected data transfer length. */ if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) { pr_warn("Rejecting SCSI DATA overflow for fabric using" " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n"); return TCM_INVALID_CDB_FIELD; } cmd->t_data_sg = sgl; cmd->t_data_nents = sgl_count; cmd->t_bidi_data_sg = sgl_bidi; cmd->t_bidi_data_nents = sgl_bidi_count; cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC; return 0; } /** * target_init_cmd - initialize se_cmd * @se_cmd: command descriptor to init * @se_sess: associated se_sess for endpoint * @sense: pointer to SCSI sense buffer * @unpacked_lun: unpacked LUN to reference for struct se_lun * @data_length: fabric expected data transfer length * @task_attr: SAM task attribute * @data_dir: DMA data direction * @flags: flags for command submission from target_sc_flags_tables * * Task tags are supported if the caller has set @se_cmd->tag. * * Returns: * - less than zero to signal active I/O shutdown failure. * - zero on success. * * If the fabric driver calls target_stop_session, then it must check the * return code and handle failures. This will never fail for other drivers, * and the return code can be ignored. */ int target_init_cmd(struct se_cmd *se_cmd, struct se_session *se_sess, unsigned char *sense, u64 unpacked_lun, u32 data_length, int task_attr, int data_dir, int flags) { struct se_portal_group *se_tpg; se_tpg = se_sess->se_tpg; BUG_ON(!se_tpg); BUG_ON(se_cmd->se_tfo || se_cmd->se_sess); if (flags & TARGET_SCF_USE_CPUID) se_cmd->se_cmd_flags |= SCF_USE_CPUID; /* * Signal bidirectional data payloads to target-core */ if (flags & TARGET_SCF_BIDI_OP) se_cmd->se_cmd_flags |= SCF_BIDI; if (flags & TARGET_SCF_UNKNOWN_SIZE) se_cmd->unknown_data_length = 1; /* * Initialize se_cmd for target operation. From this point * exceptions are handled by sending exception status via * target_core_fabric_ops->queue_status() callback */ __target_init_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, data_length, data_dir, task_attr, sense, unpacked_lun, se_sess->cmd_cnt); /* * Obtain struct se_cmd->cmd_kref reference. A second kref_get here is * necessary for fabrics using TARGET_SCF_ACK_KREF that expect a second * kref_put() to happen during fabric packet acknowledgement. */ return target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF); } EXPORT_SYMBOL_GPL(target_init_cmd); /** * target_submit_prep - prepare cmd for submission * @se_cmd: command descriptor to prep * @cdb: pointer to SCSI CDB * @sgl: struct scatterlist memory for unidirectional mapping * @sgl_count: scatterlist count for unidirectional mapping * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping * @sgl_bidi_count: scatterlist count for bidirectional READ mapping * @sgl_prot: struct scatterlist memory protection information * @sgl_prot_count: scatterlist count for protection information * @gfp: gfp allocation type * * Returns: * - less than zero to signal failure. * - zero on success. * * If failure is returned, lio will the callers queue_status to complete * the cmd. */ int target_submit_prep(struct se_cmd *se_cmd, unsigned char *cdb, struct scatterlist *sgl, u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count, struct scatterlist *sgl_prot, u32 sgl_prot_count, gfp_t gfp) { sense_reason_t rc; rc = target_cmd_init_cdb(se_cmd, cdb, gfp); if (rc) goto send_cc_direct; /* * Locate se_lun pointer and attach it to struct se_cmd */ rc = transport_lookup_cmd_lun(se_cmd); if (rc) goto send_cc_direct; rc = target_cmd_parse_cdb(se_cmd); if (rc != 0) goto generic_fail; /* * Save pointers for SGLs containing protection information, * if present. */ if (sgl_prot_count) { se_cmd->t_prot_sg = sgl_prot; se_cmd->t_prot_nents = sgl_prot_count; se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC; } /* * When a non zero sgl_count has been passed perform SGL passthrough * mapping for pre-allocated fabric memory instead of having target * core perform an internal SGL allocation.. */ if (sgl_count != 0) { BUG_ON(!sgl); rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count, sgl_bidi, sgl_bidi_count); if (rc != 0) goto generic_fail; } return 0; send_cc_direct: transport_send_check_condition_and_sense(se_cmd, rc, 0); target_put_sess_cmd(se_cmd); return -EIO; generic_fail: transport_generic_request_failure(se_cmd, rc); return -EIO; } EXPORT_SYMBOL_GPL(target_submit_prep); /** * target_submit - perform final initialization and submit cmd to LIO core * @se_cmd: command descriptor to submit * * target_submit_prep must have been called on the cmd, and this must be * called from process context. */ void target_submit(struct se_cmd *se_cmd) { struct scatterlist *sgl = se_cmd->t_data_sg; unsigned char *buf = NULL; might_sleep(); if (se_cmd->t_data_nents != 0) { BUG_ON(!sgl); /* * A work-around for tcm_loop as some userspace code via * scsi-generic do not memset their associated read buffers, * so go ahead and do that here for type non-data CDBs. Also * note that this is currently guaranteed to be a single SGL * for this case by target core in target_setup_cmd_from_cdb() * -> transport_generic_cmd_sequencer(). */ if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && se_cmd->data_direction == DMA_FROM_DEVICE) { if (sgl) buf = kmap(sg_page(sgl)) + sgl->offset; if (buf) { memset(buf, 0, sgl->length); kunmap(sg_page(sgl)); } } } /* * Check if we need to delay processing because of ALUA * Active/NonOptimized primary access state.. */ core_alua_check_nonop_delay(se_cmd); transport_handle_cdb_direct(se_cmd); } EXPORT_SYMBOL_GPL(target_submit); /** * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd * * @se_cmd: command descriptor to submit * @se_sess: associated se_sess for endpoint * @cdb: pointer to SCSI CDB * @sense: pointer to SCSI sense buffer * @unpacked_lun: unpacked LUN to reference for struct se_lun * @data_length: fabric expected data transfer length * @task_attr: SAM task attribute * @data_dir: DMA data direction * @flags: flags for command submission from target_sc_flags_tables * * Task tags are supported if the caller has set @se_cmd->tag. * * This may only be called from process context, and also currently * assumes internal allocation of fabric payload buffer by target-core. * * It also assumes interal target core SGL memory allocation. * * This function must only be used by drivers that do their own * sync during shutdown and does not use target_stop_session. If there * is a failure this function will call into the fabric driver's * queue_status with a CHECK_CONDITION. */ void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess, unsigned char *cdb, unsigned char *sense, u64 unpacked_lun, u32 data_length, int task_attr, int data_dir, int flags) { int rc; rc = target_init_cmd(se_cmd, se_sess, sense, unpacked_lun, data_length, task_attr, data_dir, flags); WARN(rc, "Invalid target_submit_cmd use. Driver must not use target_stop_session or call target_init_cmd directly.\n"); if (rc) return; if (target_submit_prep(se_cmd, cdb, NULL, 0, NULL, 0, NULL, 0, GFP_KERNEL)) return; target_submit(se_cmd); } EXPORT_SYMBOL(target_submit_cmd); static struct se_dev_plug *target_plug_device(struct se_device *se_dev) { struct se_dev_plug *se_plug; if (!se_dev->transport->plug_device) return NULL; se_plug = se_dev->transport->plug_device(se_dev); if (!se_plug) return NULL; se_plug->se_dev = se_dev; /* * We have a ref to the lun at this point, but the cmds could * complete before we unplug, so grab a ref to the se_device so we * can call back into the backend. */ config_group_get(&se_dev->dev_group); return se_plug; } static void target_unplug_device(struct se_dev_plug *se_plug) { struct se_device *se_dev = se_plug->se_dev; se_dev->transport->unplug_device(se_plug); config_group_put(&se_dev->dev_group); } void target_queued_submit_work(struct work_struct *work) { struct se_cmd_queue *sq = container_of(work, struct se_cmd_queue, work); struct se_cmd *se_cmd, *next_cmd; struct se_dev_plug *se_plug = NULL; struct se_device *se_dev = NULL; struct llist_node *cmd_list; cmd_list = llist_del_all(&sq->cmd_list); if (!cmd_list) /* Previous call took what we were queued to submit */ return; cmd_list = llist_reverse_order(cmd_list); llist_for_each_entry_safe(se_cmd, next_cmd, cmd_list, se_cmd_list) { if (!se_dev) { se_dev = se_cmd->se_dev; se_plug = target_plug_device(se_dev); } target_submit(se_cmd); } if (se_plug) target_unplug_device(se_plug); } /** * target_queue_submission - queue the cmd to run on the LIO workqueue * @se_cmd: command descriptor to submit */ void target_queue_submission(struct se_cmd *se_cmd) { struct se_device *se_dev = se_cmd->se_dev; int cpu = se_cmd->cpuid; struct se_cmd_queue *sq; sq = &se_dev->queues[cpu].sq; llist_add(&se_cmd->se_cmd_list, &sq->cmd_list); queue_work_on(cpu, target_submission_wq, &sq->work); } EXPORT_SYMBOL_GPL(target_queue_submission); static void target_complete_tmr_failure(struct work_struct *work) { struct se_cmd *se_cmd = container_of(work, struct se_cmd, work); se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST; se_cmd->se_tfo->queue_tm_rsp(se_cmd); transport_lun_remove_cmd(se_cmd); transport_cmd_check_stop_to_fabric(se_cmd); } /** * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd * for TMR CDBs * * @se_cmd: command descriptor to submit * @se_sess: associated se_sess for endpoint * @sense: pointer to SCSI sense buffer * @unpacked_lun: unpacked LUN to reference for struct se_lun * @fabric_tmr_ptr: fabric context for TMR req * @tm_type: Type of TM request * @gfp: gfp type for caller * @tag: referenced task tag for TMR_ABORT_TASK * @flags: submit cmd flags * * Callable from all contexts. **/ int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess, unsigned char *sense, u64 unpacked_lun, void *fabric_tmr_ptr, unsigned char tm_type, gfp_t gfp, u64 tag, int flags) { struct se_portal_group *se_tpg; int ret; se_tpg = se_sess->se_tpg; BUG_ON(!se_tpg); __target_init_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0, DMA_NONE, TCM_SIMPLE_TAG, sense, unpacked_lun, se_sess->cmd_cnt); /* * FIXME: Currently expect caller to handle se_cmd->se_tmr_req * allocation failure. */ ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp); if (ret < 0) return -ENOMEM; if (tm_type == TMR_ABORT_TASK) se_cmd->se_tmr_req->ref_task_tag = tag; /* See target_submit_cmd for commentary */ ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF); if (ret) { core_tmr_release_req(se_cmd->se_tmr_req); return ret; } ret = transport_lookup_tmr_lun(se_cmd); if (ret) goto failure; transport_generic_handle_tmr(se_cmd); return 0; /* * For callback during failure handling, push this work off * to process context with TMR_LUN_DOES_NOT_EXIST status. */ failure: INIT_WORK(&se_cmd->work, target_complete_tmr_failure); schedule_work(&se_cmd->work); return 0; } EXPORT_SYMBOL(target_submit_tmr); /* * Handle SAM-esque emulation for generic transport request failures. */ void transport_generic_request_failure(struct se_cmd *cmd, sense_reason_t sense_reason) { int ret = 0, post_ret; pr_debug("-----[ Storage Engine Exception; sense_reason %d\n", sense_reason); target_show_cmd("-----[ ", cmd); /* * For SAM Task Attribute emulation for failed struct se_cmd */ transport_complete_task_attr(cmd); if (cmd->transport_complete_callback) cmd->transport_complete_callback(cmd, false, &post_ret); if (cmd->transport_state & CMD_T_ABORTED) { INIT_WORK(&cmd->work, target_abort_work); queue_work(target_completion_wq, &cmd->work); return; } switch (sense_reason) { case TCM_NON_EXISTENT_LUN: case TCM_UNSUPPORTED_SCSI_OPCODE: case TCM_INVALID_CDB_FIELD: case TCM_INVALID_PARAMETER_LIST: case TCM_PARAMETER_LIST_LENGTH_ERROR: case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE: case TCM_UNKNOWN_MODE_PAGE: case TCM_WRITE_PROTECTED: case TCM_ADDRESS_OUT_OF_RANGE: case TCM_CHECK_CONDITION_ABORT_CMD: case TCM_CHECK_CONDITION_UNIT_ATTENTION: case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED: case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED: case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED: case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE: case TCM_TOO_MANY_TARGET_DESCS: case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE: case TCM_TOO_MANY_SEGMENT_DESCS: case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE: case TCM_INVALID_FIELD_IN_COMMAND_IU: case TCM_ALUA_TG_PT_STANDBY: case TCM_ALUA_TG_PT_UNAVAILABLE: case TCM_ALUA_STATE_TRANSITION: case TCM_ALUA_OFFLINE: break; case TCM_OUT_OF_RESOURCES: cmd->scsi_status = SAM_STAT_TASK_SET_FULL; goto queue_status; case TCM_LUN_BUSY: cmd->scsi_status = SAM_STAT_BUSY; goto queue_status; case TCM_RESERVATION_CONFLICT: /* * No SENSE Data payload for this case, set SCSI Status * and queue the response to $FABRIC_MOD. * * Uses linux/include/scsi/scsi.h SAM status codes defs */ cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT; /* * For UA Interlock Code 11b, a RESERVATION CONFLICT will * establish a UNIT ATTENTION with PREVIOUS RESERVATION * CONFLICT STATUS. * * See spc4r17, section 7.4.6 Control Mode Page, Table 349 */ if (cmd->se_sess && cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == TARGET_UA_INTLCK_CTRL_ESTABLISH_UA) { target_ua_allocate_lun(cmd->se_sess->se_node_acl, cmd->orig_fe_lun, 0x2C, ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS); } goto queue_status; default: pr_err("Unknown transport error for CDB 0x%02x: %d\n", cmd->t_task_cdb[0], sense_reason); sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE; break; } ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0); if (ret) goto queue_full; check_stop: transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; queue_status: trace_target_cmd_complete(cmd); ret = cmd->se_tfo->queue_status(cmd); if (!ret) goto check_stop; queue_full: transport_handle_queue_full(cmd, cmd->se_dev, ret, false); } EXPORT_SYMBOL(transport_generic_request_failure); void __target_execute_cmd(struct se_cmd *cmd, bool do_checks) { sense_reason_t ret; if (!cmd->execute_cmd) { ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; goto err; } if (do_checks) { /* * Check for an existing UNIT ATTENTION condition after * target_handle_task_attr() has done SAM task attr * checking, and possibly have already defered execution * out to target_restart_delayed_cmds() context. */ ret = target_scsi3_ua_check(cmd); if (ret) goto err; ret = target_alua_state_check(cmd); if (ret) goto err; ret = target_check_reservation(cmd); if (ret) { cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT; goto err; } } ret = cmd->execute_cmd(cmd); if (!ret) return; err: spin_lock_irq(&cmd->t_state_lock); cmd->transport_state &= ~CMD_T_SENT; spin_unlock_irq(&cmd->t_state_lock); transport_generic_request_failure(cmd, ret); } static int target_write_prot_action(struct se_cmd *cmd) { u32 sectors; /* * Perform WRITE_INSERT of PI using software emulation when backend * device has PI enabled, if the transport has not already generated * PI using hardware WRITE_INSERT offload. */ switch (cmd->prot_op) { case TARGET_PROT_DOUT_INSERT: if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT)) sbc_dif_generate(cmd); break; case TARGET_PROT_DOUT_STRIP: if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP) break; sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size); cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 0, cmd->t_prot_sg, 0); if (unlikely(cmd->pi_err)) { spin_lock_irq(&cmd->t_state_lock); cmd->transport_state &= ~CMD_T_SENT; spin_unlock_irq(&cmd->t_state_lock); transport_generic_request_failure(cmd, cmd->pi_err); return -1; } break; default: break; } return 0; } static bool target_handle_task_attr(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH) return false; cmd->se_cmd_flags |= SCF_TASK_ATTR_SET; /* * Check for the existence of HEAD_OF_QUEUE, and if true return 1 * to allow the passed struct se_cmd list of tasks to the front of the list. */ switch (cmd->sam_task_attr) { case TCM_HEAD_TAG: atomic_inc_mb(&dev->non_ordered); pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n", cmd->t_task_cdb[0]); return false; case TCM_ORDERED_TAG: atomic_inc_mb(&dev->delayed_cmd_count); pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n", cmd->t_task_cdb[0]); break; default: /* * For SIMPLE and UNTAGGED Task Attribute commands */ atomic_inc_mb(&dev->non_ordered); if (atomic_read(&dev->delayed_cmd_count) == 0) return false; break; } if (cmd->sam_task_attr != TCM_ORDERED_TAG) { atomic_inc_mb(&dev->delayed_cmd_count); /* * We will account for this when we dequeue from the delayed * list. */ atomic_dec_mb(&dev->non_ordered); } spin_lock_irq(&cmd->t_state_lock); cmd->transport_state &= ~CMD_T_SENT; spin_unlock_irq(&cmd->t_state_lock); spin_lock(&dev->delayed_cmd_lock); list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list); spin_unlock(&dev->delayed_cmd_lock); pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn", cmd->t_task_cdb[0], cmd->sam_task_attr); /* * We may have no non ordered cmds when this function started or we * could have raced with the last simple/head cmd completing, so kick * the delayed handler here. */ schedule_work(&dev->delayed_cmd_work); return true; } void target_execute_cmd(struct se_cmd *cmd) { /* * Determine if frontend context caller is requesting the stopping of * this command for frontend exceptions. * * If the received CDB has already been aborted stop processing it here. */ if (target_cmd_interrupted(cmd)) return; spin_lock_irq(&cmd->t_state_lock); cmd->t_state = TRANSPORT_PROCESSING; cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT; spin_unlock_irq(&cmd->t_state_lock); if (target_write_prot_action(cmd)) return; if (target_handle_task_attr(cmd)) return; __target_execute_cmd(cmd, true); } EXPORT_SYMBOL(target_execute_cmd); /* * Process all commands up to the last received ORDERED task attribute which * requires another blocking boundary */ void target_do_delayed_work(struct work_struct *work) { struct se_device *dev = container_of(work, struct se_device, delayed_cmd_work); spin_lock(&dev->delayed_cmd_lock); while (!dev->ordered_sync_in_progress) { struct se_cmd *cmd; if (list_empty(&dev->delayed_cmd_list)) break; cmd = list_entry(dev->delayed_cmd_list.next, struct se_cmd, se_delayed_node); if (cmd->sam_task_attr == TCM_ORDERED_TAG) { /* * Check if we started with: * [ordered] [simple] [ordered] * and we are now at the last ordered so we have to wait * for the simple cmd. */ if (atomic_read(&dev->non_ordered) > 0) break; dev->ordered_sync_in_progress = true; } list_del(&cmd->se_delayed_node); atomic_dec_mb(&dev->delayed_cmd_count); spin_unlock(&dev->delayed_cmd_lock); if (cmd->sam_task_attr != TCM_ORDERED_TAG) atomic_inc_mb(&dev->non_ordered); cmd->transport_state |= CMD_T_SENT; __target_execute_cmd(cmd, true); spin_lock(&dev->delayed_cmd_lock); } spin_unlock(&dev->delayed_cmd_lock); } /* * Called from I/O completion to determine which dormant/delayed * and ordered cmds need to have their tasks added to the execution queue. */ static void transport_complete_task_attr(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH) return; if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET)) goto restart; if (cmd->sam_task_attr == TCM_SIMPLE_TAG) { atomic_dec_mb(&dev->non_ordered); dev->dev_cur_ordered_id++; } else if (cmd->sam_task_attr == TCM_HEAD_TAG) { atomic_dec_mb(&dev->non_ordered); dev->dev_cur_ordered_id++; pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n", dev->dev_cur_ordered_id); } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) { spin_lock(&dev->delayed_cmd_lock); dev->ordered_sync_in_progress = false; spin_unlock(&dev->delayed_cmd_lock); dev->dev_cur_ordered_id++; pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n", dev->dev_cur_ordered_id); } cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET; restart: if (atomic_read(&dev->delayed_cmd_count) > 0) schedule_work(&dev->delayed_cmd_work); } static void transport_complete_qf(struct se_cmd *cmd) { int ret = 0; transport_complete_task_attr(cmd); /* * If a fabric driver ->write_pending() or ->queue_data_in() callback * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and * the same callbacks should not be retried. Return CHECK_CONDITION * if a scsi_status is not already set. * * If a fabric driver ->queue_status() has returned non zero, always * keep retrying no matter what.. */ if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) { if (cmd->scsi_status) goto queue_status; translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE); goto queue_status; } /* * Check if we need to send a sense buffer from * the struct se_cmd in question. We do NOT want * to take this path of the IO has been marked as * needing to be treated like a "normal read". This * is the case if it's a tape read, and either the * FM, EOM, or ILI bits are set, but there is no * sense data. */ if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) && cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) goto queue_status; switch (cmd->data_direction) { case DMA_FROM_DEVICE: /* queue status if not treating this as a normal read */ if (cmd->scsi_status && !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL)) goto queue_status; trace_target_cmd_complete(cmd); ret = cmd->se_tfo->queue_data_in(cmd); break; case DMA_TO_DEVICE: if (cmd->se_cmd_flags & SCF_BIDI) { ret = cmd->se_tfo->queue_data_in(cmd); break; } fallthrough; case DMA_NONE: queue_status: trace_target_cmd_complete(cmd); ret = cmd->se_tfo->queue_status(cmd); break; default: break; } if (ret < 0) { transport_handle_queue_full(cmd, cmd->se_dev, ret, false); return; } transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); } static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev, int err, bool write_pending) { /* * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or * ->queue_data_in() callbacks from new process context. * * Otherwise for other errors, transport_complete_qf() will send * CHECK_CONDITION via ->queue_status() instead of attempting to * retry associated fabric driver data-transfer callbacks. */ if (err == -EAGAIN || err == -ENOMEM) { cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP : TRANSPORT_COMPLETE_QF_OK; } else { pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err); cmd->t_state = TRANSPORT_COMPLETE_QF_ERR; } spin_lock_irq(&dev->qf_cmd_lock); list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list); atomic_inc_mb(&dev->dev_qf_count); spin_unlock_irq(&cmd->se_dev->qf_cmd_lock); schedule_work(&cmd->se_dev->qf_work_queue); } static bool target_read_prot_action(struct se_cmd *cmd) { switch (cmd->prot_op) { case TARGET_PROT_DIN_STRIP: if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) { u32 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size); cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 0, cmd->t_prot_sg, 0); if (cmd->pi_err) return true; } break; case TARGET_PROT_DIN_INSERT: if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT) break; sbc_dif_generate(cmd); break; default: break; } return false; } static void target_complete_ok_work(struct work_struct *work) { struct se_cmd *cmd = container_of(work, struct se_cmd, work); int ret; /* * Check if we need to move delayed/dormant tasks from cmds on the * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task * Attribute. */ transport_complete_task_attr(cmd); /* * Check to schedule QUEUE_FULL work, or execute an existing * cmd->transport_qf_callback() */ if (atomic_read(&cmd->se_dev->dev_qf_count) != 0) schedule_work(&cmd->se_dev->qf_work_queue); /* * Check if we need to send a sense buffer from * the struct se_cmd in question. We do NOT want * to take this path of the IO has been marked as * needing to be treated like a "normal read". This * is the case if it's a tape read, and either the * FM, EOM, or ILI bits are set, but there is no * sense data. */ if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) && cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) { WARN_ON(!cmd->scsi_status); ret = transport_send_check_condition_and_sense( cmd, 0, 1); if (ret) goto queue_full; transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; } /* * Check for a callback, used by amongst other things * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation. */ if (cmd->transport_complete_callback) { sense_reason_t rc; bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE); bool zero_dl = !(cmd->data_length); int post_ret = 0; rc = cmd->transport_complete_callback(cmd, true, &post_ret); if (!rc && !post_ret) { if (caw && zero_dl) goto queue_rsp; return; } else if (rc) { ret = transport_send_check_condition_and_sense(cmd, rc, 0); if (ret) goto queue_full; transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; } } queue_rsp: switch (cmd->data_direction) { case DMA_FROM_DEVICE: /* * if this is a READ-type IO, but SCSI status * is set, then skip returning data and just * return the status -- unless this IO is marked * as needing to be treated as a normal read, * in which case we want to go ahead and return * the data. This happens, for example, for tape * reads with the FM, EOM, or ILI bits set, with * no sense data. */ if (cmd->scsi_status && !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL)) goto queue_status; atomic_long_add(cmd->data_length, &cmd->se_lun->lun_stats.tx_data_octets); /* * Perform READ_STRIP of PI using software emulation when * backend had PI enabled, if the transport will not be * performing hardware READ_STRIP offload. */ if (target_read_prot_action(cmd)) { ret = transport_send_check_condition_and_sense(cmd, cmd->pi_err, 0); if (ret) goto queue_full; transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; } trace_target_cmd_complete(cmd); ret = cmd->se_tfo->queue_data_in(cmd); if (ret) goto queue_full; break; case DMA_TO_DEVICE: atomic_long_add(cmd->data_length, &cmd->se_lun->lun_stats.rx_data_octets); /* * Check if we need to send READ payload for BIDI-COMMAND */ if (cmd->se_cmd_flags & SCF_BIDI) { atomic_long_add(cmd->data_length, &cmd->se_lun->lun_stats.tx_data_octets); ret = cmd->se_tfo->queue_data_in(cmd); if (ret) goto queue_full; break; } fallthrough; case DMA_NONE: queue_status: trace_target_cmd_complete(cmd); ret = cmd->se_tfo->queue_status(cmd); if (ret) goto queue_full; break; default: break; } transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; queue_full: pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p," " data_direction: %d\n", cmd, cmd->data_direction); transport_handle_queue_full(cmd, cmd->se_dev, ret, false); } void target_free_sgl(struct scatterlist *sgl, int nents) { sgl_free_n_order(sgl, nents, 0); } EXPORT_SYMBOL(target_free_sgl); static inline void transport_reset_sgl_orig(struct se_cmd *cmd) { /* * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE * emulation, and free + reset pointers if necessary.. */ if (!cmd->t_data_sg_orig) return; kfree(cmd->t_data_sg); cmd->t_data_sg = cmd->t_data_sg_orig; cmd->t_data_sg_orig = NULL; cmd->t_data_nents = cmd->t_data_nents_orig; cmd->t_data_nents_orig = 0; } static inline void transport_free_pages(struct se_cmd *cmd) { if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) { target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents); cmd->t_prot_sg = NULL; cmd->t_prot_nents = 0; } if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) { /* * Release special case READ buffer payload required for * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE */ if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) { target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents); cmd->t_bidi_data_sg = NULL; cmd->t_bidi_data_nents = 0; } transport_reset_sgl_orig(cmd); return; } transport_reset_sgl_orig(cmd); target_free_sgl(cmd->t_data_sg, cmd->t_data_nents); cmd->t_data_sg = NULL; cmd->t_data_nents = 0; target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents); cmd->t_bidi_data_sg = NULL; cmd->t_bidi_data_nents = 0; } void *transport_kmap_data_sg(struct se_cmd *cmd) { struct scatterlist *sg = cmd->t_data_sg; struct page **pages; int i; /* * We need to take into account a possible offset here for fabrics like * tcm_loop who may be using a contig buffer from the SCSI midlayer for * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd() */ if (!cmd->t_data_nents) return NULL; BUG_ON(!sg); if (cmd->t_data_nents == 1) return kmap(sg_page(sg)) + sg->offset; /* >1 page. use vmap */ pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL); if (!pages) return NULL; /* convert sg[] to pages[] */ for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) { pages[i] = sg_page(sg); } cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL); kfree(pages); if (!cmd->t_data_vmap) return NULL; return cmd->t_data_vmap + cmd->t_data_sg[0].offset; } EXPORT_SYMBOL(transport_kmap_data_sg); void transport_kunmap_data_sg(struct se_cmd *cmd) { if (!cmd->t_data_nents) { return; } else if (cmd->t_data_nents == 1) { kunmap(sg_page(cmd->t_data_sg)); return; } vunmap(cmd->t_data_vmap); cmd->t_data_vmap = NULL; } EXPORT_SYMBOL(transport_kunmap_data_sg); int target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length, bool zero_page, bool chainable) { gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0); *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents); return *sgl ? 0 : -ENOMEM; } EXPORT_SYMBOL(target_alloc_sgl); /* * Allocate any required resources to execute the command. For writes we * might not have the payload yet, so notify the fabric via a call to * ->write_pending instead. Otherwise place it on the execution queue. */ sense_reason_t transport_generic_new_cmd(struct se_cmd *cmd) { unsigned long flags; int ret = 0; bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB); if (cmd->prot_op != TARGET_PROT_NORMAL && !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) { ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents, cmd->prot_length, true, false); if (ret < 0) return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } /* * Determine if the TCM fabric module has already allocated physical * memory, and is directly calling transport_generic_map_mem_to_cmd() * beforehand. */ if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) && cmd->data_length) { if ((cmd->se_cmd_flags & SCF_BIDI) || (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) { u32 bidi_length; if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) bidi_length = cmd->t_task_nolb * cmd->se_dev->dev_attrib.block_size; else bidi_length = cmd->data_length; ret = target_alloc_sgl(&cmd->t_bidi_data_sg, &cmd->t_bidi_data_nents, bidi_length, zero_flag, false); if (ret < 0) return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents, cmd->data_length, zero_flag, false); if (ret < 0) return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) && cmd->data_length) { /* * Special case for COMPARE_AND_WRITE with fabrics * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC. */ u32 caw_length = cmd->t_task_nolb * cmd->se_dev->dev_attrib.block_size; ret = target_alloc_sgl(&cmd->t_bidi_data_sg, &cmd->t_bidi_data_nents, caw_length, zero_flag, false); if (ret < 0) return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } /* * If this command is not a write we can execute it right here, * for write buffers we need to notify the fabric driver first * and let it call back once the write buffers are ready. */ target_add_to_state_list(cmd); if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) { target_execute_cmd(cmd); return 0; } spin_lock_irqsave(&cmd->t_state_lock, flags); cmd->t_state = TRANSPORT_WRITE_PENDING; /* * Determine if frontend context caller is requesting the stopping of * this command for frontend exceptions. */ if (cmd->transport_state & CMD_T_STOP && !cmd->se_tfo->write_pending_must_be_called) { pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n", __func__, __LINE__, cmd->tag); spin_unlock_irqrestore(&cmd->t_state_lock, flags); complete_all(&cmd->t_transport_stop_comp); return 0; } cmd->transport_state &= ~CMD_T_ACTIVE; spin_unlock_irqrestore(&cmd->t_state_lock, flags); ret = cmd->se_tfo->write_pending(cmd); if (ret) goto queue_full; return 0; queue_full: pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd); transport_handle_queue_full(cmd, cmd->se_dev, ret, true); return 0; } EXPORT_SYMBOL(transport_generic_new_cmd); static void transport_write_pending_qf(struct se_cmd *cmd) { unsigned long flags; int ret; bool stop; spin_lock_irqsave(&cmd->t_state_lock, flags); stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED)); spin_unlock_irqrestore(&cmd->t_state_lock, flags); if (stop) { pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n", __func__, __LINE__, cmd->tag); complete_all(&cmd->t_transport_stop_comp); return; } ret = cmd->se_tfo->write_pending(cmd); if (ret) { pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd); transport_handle_queue_full(cmd, cmd->se_dev, ret, true); } } static bool __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *, unsigned long *flags); static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas) { unsigned long flags; spin_lock_irqsave(&cmd->t_state_lock, flags); __transport_wait_for_tasks(cmd, true, aborted, tas, &flags); spin_unlock_irqrestore(&cmd->t_state_lock, flags); } /* * Call target_put_sess_cmd() and wait until target_release_cmd_kref(@cmd) has * finished. */ void target_put_cmd_and_wait(struct se_cmd *cmd) { DECLARE_COMPLETION_ONSTACK(compl); WARN_ON_ONCE(cmd->abrt_compl); cmd->abrt_compl = &compl; target_put_sess_cmd(cmd); wait_for_completion(&compl); } /* * This function is called by frontend drivers after processing of a command * has finished. * * The protocol for ensuring that either the regular frontend command * processing flow or target_handle_abort() code drops one reference is as * follows: * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause * the frontend driver to call this function synchronously or asynchronously. * That will cause one reference to be dropped. * - During regular command processing the target core sets CMD_T_COMPLETE * before invoking one of the .queue_*() functions. * - The code that aborts commands skips commands and TMFs for which * CMD_T_COMPLETE has been set. * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for * commands that will be aborted. * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set * transport_generic_free_cmd() skips its call to target_put_sess_cmd(). * - For aborted commands for which CMD_T_TAS has been set .queue_status() will * be called and will drop a reference. * - For aborted commands for which CMD_T_TAS has not been set .aborted_task() * will be called. target_handle_abort() will drop the final reference. */ int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks) { DECLARE_COMPLETION_ONSTACK(compl); int ret = 0; bool aborted = false, tas = false; if (wait_for_tasks) target_wait_free_cmd(cmd, &aborted, &tas); if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) { /* * Handle WRITE failure case where transport_generic_new_cmd() * has already added se_cmd to state_list, but fabric has * failed command before I/O submission. */ if (cmd->state_active) target_remove_from_state_list(cmd); if (cmd->se_lun) transport_lun_remove_cmd(cmd); } if (aborted) cmd->free_compl = &compl; ret = target_put_sess_cmd(cmd); if (aborted) { pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag); wait_for_completion(&compl); ret = 1; } return ret; } EXPORT_SYMBOL(transport_generic_free_cmd); /** * target_get_sess_cmd - Verify the session is accepting cmds and take ref * @se_cmd: command descriptor to add * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd() */ int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref) { int ret = 0; /* * Add a second kref if the fabric caller is expecting to handle * fabric acknowledgement that requires two target_put_sess_cmd() * invocations before se_cmd descriptor release. */ if (ack_kref) { kref_get(&se_cmd->cmd_kref); se_cmd->se_cmd_flags |= SCF_ACK_KREF; } /* * Users like xcopy do not use counters since they never do a stop * and wait. */ if (se_cmd->cmd_cnt) { if (!percpu_ref_tryget_live(&se_cmd->cmd_cnt->refcnt)) ret = -ESHUTDOWN; } if (ret && ack_kref) target_put_sess_cmd(se_cmd); return ret; } EXPORT_SYMBOL(target_get_sess_cmd); static void target_free_cmd_mem(struct se_cmd *cmd) { transport_free_pages(cmd); if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) core_tmr_release_req(cmd->se_tmr_req); if (cmd->t_task_cdb != cmd->__t_task_cdb) kfree(cmd->t_task_cdb); } static void target_release_cmd_kref(struct kref *kref) { struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref); struct target_cmd_counter *cmd_cnt = se_cmd->cmd_cnt; struct completion *free_compl = se_cmd->free_compl; struct completion *abrt_compl = se_cmd->abrt_compl; target_free_cmd_mem(se_cmd); se_cmd->se_tfo->release_cmd(se_cmd); if (free_compl) complete(free_compl); if (abrt_compl) complete(abrt_compl); if (cmd_cnt) percpu_ref_put(&cmd_cnt->refcnt); } /** * target_put_sess_cmd - decrease the command reference count * @se_cmd: command to drop a reference from * * Returns 1 if and only if this target_put_sess_cmd() call caused the * refcount to drop to zero. Returns zero otherwise. */ int target_put_sess_cmd(struct se_cmd *se_cmd) { return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref); } EXPORT_SYMBOL(target_put_sess_cmd); static const char *data_dir_name(enum dma_data_direction d) { switch (d) { case DMA_BIDIRECTIONAL: return "BIDI"; case DMA_TO_DEVICE: return "WRITE"; case DMA_FROM_DEVICE: return "READ"; case DMA_NONE: return "NONE"; } return "(?)"; } static const char *cmd_state_name(enum transport_state_table t) { switch (t) { case TRANSPORT_NO_STATE: return "NO_STATE"; case TRANSPORT_NEW_CMD: return "NEW_CMD"; case TRANSPORT_WRITE_PENDING: return "WRITE_PENDING"; case TRANSPORT_PROCESSING: return "PROCESSING"; case TRANSPORT_COMPLETE: return "COMPLETE"; case TRANSPORT_ISTATE_PROCESSING: return "ISTATE_PROCESSING"; case TRANSPORT_COMPLETE_QF_WP: return "COMPLETE_QF_WP"; case TRANSPORT_COMPLETE_QF_OK: return "COMPLETE_QF_OK"; case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR"; } return "(?)"; } static void target_append_str(char **str, const char *txt) { char *prev = *str; *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) : kstrdup(txt, GFP_ATOMIC); kfree(prev); } /* * Convert a transport state bitmask into a string. The caller is * responsible for freeing the returned pointer. */ static char *target_ts_to_str(u32 ts) { char *str = NULL; if (ts & CMD_T_ABORTED) target_append_str(&str, "aborted"); if (ts & CMD_T_ACTIVE) target_append_str(&str, "active"); if (ts & CMD_T_COMPLETE) target_append_str(&str, "complete"); if (ts & CMD_T_SENT) target_append_str(&str, "sent"); if (ts & CMD_T_STOP) target_append_str(&str, "stop"); if (ts & CMD_T_FABRIC_STOP) target_append_str(&str, "fabric_stop"); return str; } static const char *target_tmf_name(enum tcm_tmreq_table tmf) { switch (tmf) { case TMR_ABORT_TASK: return "ABORT_TASK"; case TMR_ABORT_TASK_SET: return "ABORT_TASK_SET"; case TMR_CLEAR_ACA: return "CLEAR_ACA"; case TMR_CLEAR_TASK_SET: return "CLEAR_TASK_SET"; case TMR_LUN_RESET: return "LUN_RESET"; case TMR_TARGET_WARM_RESET: return "TARGET_WARM_RESET"; case TMR_TARGET_COLD_RESET: return "TARGET_COLD_RESET"; case TMR_LUN_RESET_PRO: return "LUN_RESET_PRO"; case TMR_UNKNOWN: break; } return "(?)"; } void target_show_cmd(const char *pfx, struct se_cmd *cmd) { char *ts_str = target_ts_to_str(cmd->transport_state); const u8 *cdb = cmd->t_task_cdb; struct se_tmr_req *tmf = cmd->se_tmr_req; if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) { pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n", pfx, cdb[0], cdb[1], cmd->tag, data_dir_name(cmd->data_direction), cmd->se_tfo->get_cmd_state(cmd), cmd_state_name(cmd->t_state), cmd->data_length, kref_read(&cmd->cmd_kref), ts_str); } else { pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n", pfx, target_tmf_name(tmf->function), cmd->tag, tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd), cmd_state_name(cmd->t_state), kref_read(&cmd->cmd_kref), ts_str); } kfree(ts_str); } EXPORT_SYMBOL(target_show_cmd); static void target_stop_cmd_counter_confirm(struct percpu_ref *ref) { struct target_cmd_counter *cmd_cnt = container_of(ref, struct target_cmd_counter, refcnt); complete_all(&cmd_cnt->stop_done); } /** * target_stop_cmd_counter - Stop new IO from being added to the counter. * @cmd_cnt: counter to stop */ void target_stop_cmd_counter(struct target_cmd_counter *cmd_cnt) { pr_debug("Stopping command counter.\n"); if (!atomic_cmpxchg(&cmd_cnt->stopped, 0, 1)) percpu_ref_kill_and_confirm(&cmd_cnt->refcnt, target_stop_cmd_counter_confirm); } EXPORT_SYMBOL_GPL(target_stop_cmd_counter); /** * target_stop_session - Stop new IO from being queued on the session. * @se_sess: session to stop */ void target_stop_session(struct se_session *se_sess) { target_stop_cmd_counter(se_sess->cmd_cnt); } EXPORT_SYMBOL(target_stop_session); /** * target_wait_for_cmds - Wait for outstanding cmds. * @cmd_cnt: counter to wait for active I/O for. */ void target_wait_for_cmds(struct target_cmd_counter *cmd_cnt) { int ret; WARN_ON_ONCE(!atomic_read(&cmd_cnt->stopped)); do { pr_debug("Waiting for running cmds to complete.\n"); ret = wait_event_timeout(cmd_cnt->refcnt_wq, percpu_ref_is_zero(&cmd_cnt->refcnt), 180 * HZ); } while (ret <= 0); wait_for_completion(&cmd_cnt->stop_done); pr_debug("Waiting for cmds done.\n"); } EXPORT_SYMBOL_GPL(target_wait_for_cmds); /** * target_wait_for_sess_cmds - Wait for outstanding commands * @se_sess: session to wait for active I/O */ void target_wait_for_sess_cmds(struct se_session *se_sess) { target_wait_for_cmds(se_sess->cmd_cnt); } EXPORT_SYMBOL(target_wait_for_sess_cmds); /* * Prevent that new percpu_ref_tryget_live() calls succeed and wait until * all references to the LUN have been released. Called during LUN shutdown. */ void transport_clear_lun_ref(struct se_lun *lun) { percpu_ref_kill(&lun->lun_ref); wait_for_completion(&lun->lun_shutdown_comp); } static bool __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop, bool *aborted, bool *tas, unsigned long *flags) __releases(&cmd->t_state_lock) __acquires(&cmd->t_state_lock) { lockdep_assert_held(&cmd->t_state_lock); if (fabric_stop) cmd->transport_state |= CMD_T_FABRIC_STOP; if (cmd->transport_state & CMD_T_ABORTED) *aborted = true; if (cmd->transport_state & CMD_T_TAS) *tas = true; if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) && !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) return false; if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) && !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) return false; if (!(cmd->transport_state & CMD_T_ACTIVE)) return false; if (fabric_stop && *aborted) return false; cmd->transport_state |= CMD_T_STOP; target_show_cmd("wait_for_tasks: Stopping ", cmd); spin_unlock_irqrestore(&cmd->t_state_lock, *flags); while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp, 180 * HZ)) target_show_cmd("wait for tasks: ", cmd); spin_lock_irqsave(&cmd->t_state_lock, *flags); cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP); pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->" "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag); return true; } /** * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp * @cmd: command to wait on */ bool transport_wait_for_tasks(struct se_cmd *cmd) { unsigned long flags; bool ret, aborted = false, tas = false; spin_lock_irqsave(&cmd->t_state_lock, flags); ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags); spin_unlock_irqrestore(&cmd->t_state_lock, flags); return ret; } EXPORT_SYMBOL(transport_wait_for_tasks); struct sense_detail { u8 key; u8 asc; u8 ascq; bool add_sense_info; }; static const struct sense_detail sense_detail_table[] = { [TCM_NO_SENSE] = { .key = NOT_READY }, [TCM_NON_EXISTENT_LUN] = { .key = ILLEGAL_REQUEST, .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */ }, [TCM_UNSUPPORTED_SCSI_OPCODE] = { .key = ILLEGAL_REQUEST, .asc = 0x20, /* INVALID COMMAND OPERATION CODE */ }, [TCM_SECTOR_COUNT_TOO_MANY] = { .key = ILLEGAL_REQUEST, .asc = 0x20, /* INVALID COMMAND OPERATION CODE */ }, [TCM_UNKNOWN_MODE_PAGE] = { .key = ILLEGAL_REQUEST, .asc = 0x24, /* INVALID FIELD IN CDB */ }, [TCM_CHECK_CONDITION_ABORT_CMD] = { .key = ABORTED_COMMAND, .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */ .ascq = 0x03, }, [TCM_INCORRECT_AMOUNT_OF_DATA] = { .key = ABORTED_COMMAND, .asc = 0x0c, /* WRITE ERROR */ .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */ }, [TCM_INVALID_CDB_FIELD] = { .key = ILLEGAL_REQUEST, .asc = 0x24, /* INVALID FIELD IN CDB */ }, [TCM_INVALID_PARAMETER_LIST] = { .key = ILLEGAL_REQUEST, .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */ }, [TCM_TOO_MANY_TARGET_DESCS] = { .key = ILLEGAL_REQUEST, .asc = 0x26, .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */ }, [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = { .key = ILLEGAL_REQUEST, .asc = 0x26, .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */ }, [TCM_TOO_MANY_SEGMENT_DESCS] = { .key = ILLEGAL_REQUEST, .asc = 0x26, .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */ }, [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = { .key = ILLEGAL_REQUEST, .asc = 0x26, .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */ }, [TCM_PARAMETER_LIST_LENGTH_ERROR] = { .key = ILLEGAL_REQUEST, .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */ }, [TCM_UNEXPECTED_UNSOLICITED_DATA] = { .key = ILLEGAL_REQUEST, .asc = 0x0c, /* WRITE ERROR */ .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */ }, [TCM_SERVICE_CRC_ERROR] = { .key = ABORTED_COMMAND, .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */ .ascq = 0x05, /* N/A */ }, [TCM_SNACK_REJECTED] = { .key = ABORTED_COMMAND, .asc = 0x11, /* READ ERROR */ .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */ }, [TCM_WRITE_PROTECTED] = { .key = DATA_PROTECT, .asc = 0x27, /* WRITE PROTECTED */ }, [TCM_ADDRESS_OUT_OF_RANGE] = { .key = ILLEGAL_REQUEST, .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */ }, [TCM_CHECK_CONDITION_UNIT_ATTENTION] = { .key = UNIT_ATTENTION, }, [TCM_MISCOMPARE_VERIFY] = { .key = MISCOMPARE, .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */ .ascq = 0x00, .add_sense_info = true, }, [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = { .key = ABORTED_COMMAND, .asc = 0x10, .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */ .add_sense_info = true, }, [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = { .key = ABORTED_COMMAND, .asc = 0x10, .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */ .add_sense_info = true, }, [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = { .key = ABORTED_COMMAND, .asc = 0x10, .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */ .add_sense_info = true, }, [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = { .key = COPY_ABORTED, .asc = 0x0d, .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */ }, [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = { /* * Returning ILLEGAL REQUEST would cause immediate IO errors on * Solaris initiators. Returning NOT READY instead means the * operations will be retried a finite number of times and we * can survive intermittent errors. */ .key = NOT_READY, .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */ }, [TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = { /* * From spc4r22 section5.7.7,5.7.8 * If a PERSISTENT RESERVE OUT command with a REGISTER service action * or a REGISTER AND IGNORE EXISTING KEY service action or * REGISTER AND MOVE service actionis attempted, * but there are insufficient device server resources to complete the * operation, then the command shall be terminated with CHECK CONDITION * status, with the sense key set to ILLEGAL REQUEST,and the additonal * sense code set to INSUFFICIENT REGISTRATION RESOURCES. */ .key = ILLEGAL_REQUEST, .asc = 0x55, .ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */ }, [TCM_INVALID_FIELD_IN_COMMAND_IU] = { .key = ILLEGAL_REQUEST, .asc = 0x0e, .ascq = 0x03, /* INVALID FIELD IN COMMAND INFORMATION UNIT */ }, [TCM_ALUA_TG_PT_STANDBY] = { .key = NOT_READY, .asc = 0x04, .ascq = ASCQ_04H_ALUA_TG_PT_STANDBY, }, [TCM_ALUA_TG_PT_UNAVAILABLE] = { .key = NOT_READY, .asc = 0x04, .ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE, }, [TCM_ALUA_STATE_TRANSITION] = { .key = NOT_READY, .asc = 0x04, .ascq = ASCQ_04H_ALUA_STATE_TRANSITION, }, [TCM_ALUA_OFFLINE] = { .key = NOT_READY, .asc = 0x04, .ascq = ASCQ_04H_ALUA_OFFLINE, }, }; /** * translate_sense_reason - translate a sense reason into T10 key, asc and ascq * @cmd: SCSI command in which the resulting sense buffer or SCSI status will * be stored. * @reason: LIO sense reason code. If this argument has the value * TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If * dequeuing a unit attention fails due to multiple commands being processed * concurrently, set the command status to BUSY. * * Return: 0 upon success or -EINVAL if the sense buffer is too small. */ static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason) { const struct sense_detail *sd; u8 *buffer = cmd->sense_buffer; int r = (__force int)reason; u8 key, asc, ascq; bool desc_format = target_sense_desc_format(cmd->se_dev); if (r < ARRAY_SIZE(sense_detail_table) && sense_detail_table[r].key) sd = &sense_detail_table[r]; else sd = &sense_detail_table[(__force int) TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE]; key = sd->key; if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) { if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc, &ascq)) { cmd->scsi_status = SAM_STAT_BUSY; return; } } else { WARN_ON_ONCE(sd->asc == 0); asc = sd->asc; ascq = sd->ascq; } cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE; cmd->scsi_status = SAM_STAT_CHECK_CONDITION; cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER; scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq); if (sd->add_sense_info) WARN_ON_ONCE(scsi_set_sense_information(buffer, cmd->scsi_sense_length, cmd->sense_info) < 0); } int transport_send_check_condition_and_sense(struct se_cmd *cmd, sense_reason_t reason, int from_transport) { unsigned long flags; WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB); spin_lock_irqsave(&cmd->t_state_lock, flags); if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) { spin_unlock_irqrestore(&cmd->t_state_lock, flags); return 0; } cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION; spin_unlock_irqrestore(&cmd->t_state_lock, flags); if (!from_transport) translate_sense_reason(cmd, reason); trace_target_cmd_complete(cmd); return cmd->se_tfo->queue_status(cmd); } EXPORT_SYMBOL(transport_send_check_condition_and_sense); /** * target_send_busy - Send SCSI BUSY status back to the initiator * @cmd: SCSI command for which to send a BUSY reply. * * Note: Only call this function if target_submit_cmd*() failed. */ int target_send_busy(struct se_cmd *cmd) { WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB); cmd->scsi_status = SAM_STAT_BUSY; trace_target_cmd_complete(cmd); return cmd->se_tfo->queue_status(cmd); } EXPORT_SYMBOL(target_send_busy); static void target_tmr_work(struct work_struct *work) { struct se_cmd *cmd = container_of(work, struct se_cmd, work); struct se_device *dev = cmd->se_dev; struct se_tmr_req *tmr = cmd->se_tmr_req; int ret; if (cmd->transport_state & CMD_T_ABORTED) goto aborted; switch (tmr->function) { case TMR_ABORT_TASK: core_tmr_abort_task(dev, tmr, cmd->se_sess); break; case TMR_ABORT_TASK_SET: case TMR_CLEAR_ACA: case TMR_CLEAR_TASK_SET: tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED; break; case TMR_LUN_RESET: ret = core_tmr_lun_reset(dev, tmr, NULL, NULL); tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE : TMR_FUNCTION_REJECTED; if (tmr->response == TMR_FUNCTION_COMPLETE) { target_dev_ua_allocate(dev, 0x29, ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED); } break; case TMR_TARGET_WARM_RESET: tmr->response = TMR_FUNCTION_REJECTED; break; case TMR_TARGET_COLD_RESET: tmr->response = TMR_FUNCTION_REJECTED; break; default: pr_err("Unknown TMR function: 0x%02x.\n", tmr->function); tmr->response = TMR_FUNCTION_REJECTED; break; } if (cmd->transport_state & CMD_T_ABORTED) goto aborted; cmd->se_tfo->queue_tm_rsp(cmd); transport_lun_remove_cmd(cmd); transport_cmd_check_stop_to_fabric(cmd); return; aborted: target_handle_abort(cmd); } int transport_generic_handle_tmr( struct se_cmd *cmd) { unsigned long flags; bool aborted = false; spin_lock_irqsave(&cmd->t_state_lock, flags); if (cmd->transport_state & CMD_T_ABORTED) { aborted = true; } else { cmd->t_state = TRANSPORT_ISTATE_PROCESSING; cmd->transport_state |= CMD_T_ACTIVE; } spin_unlock_irqrestore(&cmd->t_state_lock, flags); if (aborted) { pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function, cmd->se_tmr_req->ref_task_tag, cmd->tag); target_handle_abort(cmd); return 0; } INIT_WORK(&cmd->work, target_tmr_work); schedule_work(&cmd->work); return 0; } EXPORT_SYMBOL(transport_generic_handle_tmr); bool target_check_wce(struct se_device *dev) { bool wce = false; if (dev->transport->get_write_cache) wce = dev->transport->get_write_cache(dev); else if (dev->dev_attrib.emulate_write_cache > 0) wce = true; return wce; } bool target_check_fua(struct se_device *dev) { return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0; }