diff options
Diffstat (limited to 'drivers/target/target_core_transport.c')
| -rw-r--r-- | drivers/target/target_core_transport.c | 3670 |
1 files changed, 3670 insertions, 0 deletions
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c new file mode 100644 index 000000000..0686882bc --- /dev/null +++ b/drivers/target/target_core_transport.c @@ -0,0 +1,3670 @@ +// 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 <nab@kernel.org> + * + ******************************************************************************/ + +#include <linux/net.h> +#include <linux/delay.h> +#include <linux/string.h> +#include <linux/timer.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/kthread.h> +#include <linux/in.h> +#include <linux/cdrom.h> +#include <linux/module.h> +#include <linux/ratelimit.h> +#include <linux/vmalloc.h> +#include <asm/unaligned.h> +#include <net/sock.h> +#include <net/tcp.h> +#include <scsi/scsi_proto.h> +#include <scsi/scsi_common.h> + +#include <target/target_core_base.h> +#include <target/target_core_backend.h> +#include <target/target_core_fabric.h> + +#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 <trace/events/target.h> + +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); + kfree(cmd_cnt); +} +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; +} |