1 /*******************************************************************************
2 * Filename: target_core_transport.c
4 * This file contains the Generic Target Engine Core.
6 * (c) Copyright 2002-2013 Datera, Inc.
8 * Nicholas A. Bellinger <nab@kernel.org>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 ******************************************************************************/
26 #include <linux/net.h>
27 #include <linux/delay.h>
28 #include <linux/string.h>
29 #include <linux/timer.h>
30 #include <linux/slab.h>
31 #include <linux/spinlock.h>
32 #include <linux/kthread.h>
34 #include <linux/cdrom.h>
35 #include <linux/module.h>
36 #include <linux/ratelimit.h>
37 #include <linux/vmalloc.h>
38 #include <asm/unaligned.h>
41 #include <scsi/scsi_proto.h>
42 #include <scsi/scsi_common.h>
44 #include <target/target_core_base.h>
45 #include <target/target_core_backend.h>
46 #include <target/target_core_fabric.h>
48 #include "target_core_internal.h"
49 #include "target_core_alua.h"
50 #include "target_core_pr.h"
51 #include "target_core_ua.h"
53 #define CREATE_TRACE_POINTS
54 #include <trace/events/target.h>
56 static struct workqueue_struct *target_completion_wq;
57 static struct kmem_cache *se_sess_cache;
58 struct kmem_cache *se_ua_cache;
59 struct kmem_cache *t10_pr_reg_cache;
60 struct kmem_cache *t10_alua_lu_gp_cache;
61 struct kmem_cache *t10_alua_lu_gp_mem_cache;
62 struct kmem_cache *t10_alua_tg_pt_gp_cache;
63 struct kmem_cache *t10_alua_lba_map_cache;
64 struct kmem_cache *t10_alua_lba_map_mem_cache;
66 static void transport_complete_task_attr(struct se_cmd *cmd);
67 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason);
68 static void transport_handle_queue_full(struct se_cmd *cmd,
69 struct se_device *dev, int err, bool write_pending);
70 static void target_complete_ok_work(struct work_struct *work);
72 int init_se_kmem_caches(void)
74 se_sess_cache = kmem_cache_create("se_sess_cache",
75 sizeof(struct se_session), __alignof__(struct se_session),
78 pr_err("kmem_cache_create() for struct se_session"
82 se_ua_cache = kmem_cache_create("se_ua_cache",
83 sizeof(struct se_ua), __alignof__(struct se_ua),
86 pr_err("kmem_cache_create() for struct se_ua failed\n");
87 goto out_free_sess_cache;
89 t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
90 sizeof(struct t10_pr_registration),
91 __alignof__(struct t10_pr_registration), 0, NULL);
92 if (!t10_pr_reg_cache) {
93 pr_err("kmem_cache_create() for struct t10_pr_registration"
95 goto out_free_ua_cache;
97 t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
98 sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
100 if (!t10_alua_lu_gp_cache) {
101 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
103 goto out_free_pr_reg_cache;
105 t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
106 sizeof(struct t10_alua_lu_gp_member),
107 __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
108 if (!t10_alua_lu_gp_mem_cache) {
109 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
111 goto out_free_lu_gp_cache;
113 t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
114 sizeof(struct t10_alua_tg_pt_gp),
115 __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
116 if (!t10_alua_tg_pt_gp_cache) {
117 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
119 goto out_free_lu_gp_mem_cache;
121 t10_alua_lba_map_cache = kmem_cache_create(
122 "t10_alua_lba_map_cache",
123 sizeof(struct t10_alua_lba_map),
124 __alignof__(struct t10_alua_lba_map), 0, NULL);
125 if (!t10_alua_lba_map_cache) {
126 pr_err("kmem_cache_create() for t10_alua_lba_map_"
128 goto out_free_tg_pt_gp_cache;
130 t10_alua_lba_map_mem_cache = kmem_cache_create(
131 "t10_alua_lba_map_mem_cache",
132 sizeof(struct t10_alua_lba_map_member),
133 __alignof__(struct t10_alua_lba_map_member), 0, NULL);
134 if (!t10_alua_lba_map_mem_cache) {
135 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
137 goto out_free_lba_map_cache;
140 target_completion_wq = alloc_workqueue("target_completion",
142 if (!target_completion_wq)
143 goto out_free_lba_map_mem_cache;
147 out_free_lba_map_mem_cache:
148 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
149 out_free_lba_map_cache:
150 kmem_cache_destroy(t10_alua_lba_map_cache);
151 out_free_tg_pt_gp_cache:
152 kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
153 out_free_lu_gp_mem_cache:
154 kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
155 out_free_lu_gp_cache:
156 kmem_cache_destroy(t10_alua_lu_gp_cache);
157 out_free_pr_reg_cache:
158 kmem_cache_destroy(t10_pr_reg_cache);
160 kmem_cache_destroy(se_ua_cache);
162 kmem_cache_destroy(se_sess_cache);
167 void release_se_kmem_caches(void)
169 destroy_workqueue(target_completion_wq);
170 kmem_cache_destroy(se_sess_cache);
171 kmem_cache_destroy(se_ua_cache);
172 kmem_cache_destroy(t10_pr_reg_cache);
173 kmem_cache_destroy(t10_alua_lu_gp_cache);
174 kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
175 kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
176 kmem_cache_destroy(t10_alua_lba_map_cache);
177 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
180 /* This code ensures unique mib indexes are handed out. */
181 static DEFINE_SPINLOCK(scsi_mib_index_lock);
182 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
185 * Allocate a new row index for the entry type specified
187 u32 scsi_get_new_index(scsi_index_t type)
191 BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
193 spin_lock(&scsi_mib_index_lock);
194 new_index = ++scsi_mib_index[type];
195 spin_unlock(&scsi_mib_index_lock);
200 void transport_subsystem_check_init(void)
203 static int sub_api_initialized;
205 if (sub_api_initialized)
208 ret = request_module("target_core_iblock");
210 pr_err("Unable to load target_core_iblock\n");
212 ret = request_module("target_core_file");
214 pr_err("Unable to load target_core_file\n");
216 ret = request_module("target_core_pscsi");
218 pr_err("Unable to load target_core_pscsi\n");
220 ret = request_module("target_core_user");
222 pr_err("Unable to load target_core_user\n");
224 sub_api_initialized = 1;
227 static void target_release_sess_cmd_refcnt(struct percpu_ref *ref)
229 struct se_session *sess = container_of(ref, typeof(*sess), cmd_count);
231 wake_up(&sess->cmd_list_wq);
235 * transport_init_session - initialize a session object
236 * @se_sess: Session object pointer.
238 * The caller must have zero-initialized @se_sess before calling this function.
240 int transport_init_session(struct se_session *se_sess)
242 INIT_LIST_HEAD(&se_sess->sess_list);
243 INIT_LIST_HEAD(&se_sess->sess_acl_list);
244 INIT_LIST_HEAD(&se_sess->sess_cmd_list);
245 spin_lock_init(&se_sess->sess_cmd_lock);
246 init_waitqueue_head(&se_sess->cmd_list_wq);
247 return percpu_ref_init(&se_sess->cmd_count,
248 target_release_sess_cmd_refcnt, 0, GFP_KERNEL);
250 EXPORT_SYMBOL(transport_init_session);
253 * transport_alloc_session - allocate a session object and initialize it
254 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
256 struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
258 struct se_session *se_sess;
261 se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
263 pr_err("Unable to allocate struct se_session from"
265 return ERR_PTR(-ENOMEM);
267 ret = transport_init_session(se_sess);
269 kmem_cache_free(se_sess_cache, se_sess);
272 se_sess->sup_prot_ops = sup_prot_ops;
276 EXPORT_SYMBOL(transport_alloc_session);
279 * transport_alloc_session_tags - allocate target driver private data
280 * @se_sess: Session pointer.
281 * @tag_num: Maximum number of in-flight commands between initiator and target.
282 * @tag_size: Size in bytes of the private data a target driver associates with
285 int transport_alloc_session_tags(struct se_session *se_sess,
286 unsigned int tag_num, unsigned int tag_size)
290 se_sess->sess_cmd_map = kcalloc(tag_size, tag_num,
291 GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
292 if (!se_sess->sess_cmd_map) {
293 se_sess->sess_cmd_map = vzalloc(array_size(tag_size, tag_num));
294 if (!se_sess->sess_cmd_map) {
295 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
300 rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
301 false, GFP_KERNEL, NUMA_NO_NODE);
303 pr_err("Unable to init se_sess->sess_tag_pool,"
304 " tag_num: %u\n", tag_num);
305 kvfree(se_sess->sess_cmd_map);
306 se_sess->sess_cmd_map = NULL;
312 EXPORT_SYMBOL(transport_alloc_session_tags);
315 * transport_init_session_tags - allocate a session and target driver private data
316 * @tag_num: Maximum number of in-flight commands between initiator and target.
317 * @tag_size: Size in bytes of the private data a target driver associates with
319 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
321 static struct se_session *
322 transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
323 enum target_prot_op sup_prot_ops)
325 struct se_session *se_sess;
328 if (tag_num != 0 && !tag_size) {
329 pr_err("init_session_tags called with percpu-ida tag_num:"
330 " %u, but zero tag_size\n", tag_num);
331 return ERR_PTR(-EINVAL);
333 if (!tag_num && tag_size) {
334 pr_err("init_session_tags called with percpu-ida tag_size:"
335 " %u, but zero tag_num\n", tag_size);
336 return ERR_PTR(-EINVAL);
339 se_sess = transport_alloc_session(sup_prot_ops);
343 rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
345 transport_free_session(se_sess);
346 return ERR_PTR(-ENOMEM);
353 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
355 void __transport_register_session(
356 struct se_portal_group *se_tpg,
357 struct se_node_acl *se_nacl,
358 struct se_session *se_sess,
359 void *fabric_sess_ptr)
361 const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
362 unsigned char buf[PR_REG_ISID_LEN];
365 se_sess->se_tpg = se_tpg;
366 se_sess->fabric_sess_ptr = fabric_sess_ptr;
368 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
370 * Only set for struct se_session's that will actually be moving I/O.
371 * eg: *NOT* discovery sessions.
376 * Determine if fabric allows for T10-PI feature bits exposed to
377 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
379 * If so, then always save prot_type on a per se_node_acl node
380 * basis and re-instate the previous sess_prot_type to avoid
381 * disabling PI from below any previously initiator side
384 if (se_nacl->saved_prot_type)
385 se_sess->sess_prot_type = se_nacl->saved_prot_type;
386 else if (tfo->tpg_check_prot_fabric_only)
387 se_sess->sess_prot_type = se_nacl->saved_prot_type =
388 tfo->tpg_check_prot_fabric_only(se_tpg);
390 * If the fabric module supports an ISID based TransportID,
391 * save this value in binary from the fabric I_T Nexus now.
393 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
394 memset(&buf[0], 0, PR_REG_ISID_LEN);
395 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
396 &buf[0], PR_REG_ISID_LEN);
397 se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
400 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
402 * The se_nacl->nacl_sess pointer will be set to the
403 * last active I_T Nexus for each struct se_node_acl.
405 se_nacl->nacl_sess = se_sess;
407 list_add_tail(&se_sess->sess_acl_list,
408 &se_nacl->acl_sess_list);
409 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
411 list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
413 pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
414 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
416 EXPORT_SYMBOL(__transport_register_session);
418 void transport_register_session(
419 struct se_portal_group *se_tpg,
420 struct se_node_acl *se_nacl,
421 struct se_session *se_sess,
422 void *fabric_sess_ptr)
426 spin_lock_irqsave(&se_tpg->session_lock, flags);
427 __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
428 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
430 EXPORT_SYMBOL(transport_register_session);
433 target_setup_session(struct se_portal_group *tpg,
434 unsigned int tag_num, unsigned int tag_size,
435 enum target_prot_op prot_op,
436 const char *initiatorname, void *private,
437 int (*callback)(struct se_portal_group *,
438 struct se_session *, void *))
440 struct se_session *sess;
443 * If the fabric driver is using percpu-ida based pre allocation
444 * of I/O descriptor tags, go ahead and perform that setup now..
447 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
449 sess = transport_alloc_session(prot_op);
454 sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
455 (unsigned char *)initiatorname);
456 if (!sess->se_node_acl) {
457 transport_free_session(sess);
458 return ERR_PTR(-EACCES);
461 * Go ahead and perform any remaining fabric setup that is
462 * required before transport_register_session().
464 if (callback != NULL) {
465 int rc = callback(tpg, sess, private);
467 transport_free_session(sess);
472 transport_register_session(tpg, sess->se_node_acl, sess, private);
475 EXPORT_SYMBOL(target_setup_session);
477 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
479 struct se_session *se_sess;
482 spin_lock_bh(&se_tpg->session_lock);
483 list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
484 if (!se_sess->se_node_acl)
486 if (!se_sess->se_node_acl->dynamic_node_acl)
488 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
491 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
492 se_sess->se_node_acl->initiatorname);
493 len += 1; /* Include NULL terminator */
495 spin_unlock_bh(&se_tpg->session_lock);
499 EXPORT_SYMBOL(target_show_dynamic_sessions);
501 static void target_complete_nacl(struct kref *kref)
503 struct se_node_acl *nacl = container_of(kref,
504 struct se_node_acl, acl_kref);
505 struct se_portal_group *se_tpg = nacl->se_tpg;
507 if (!nacl->dynamic_stop) {
508 complete(&nacl->acl_free_comp);
512 mutex_lock(&se_tpg->acl_node_mutex);
513 list_del_init(&nacl->acl_list);
514 mutex_unlock(&se_tpg->acl_node_mutex);
516 core_tpg_wait_for_nacl_pr_ref(nacl);
517 core_free_device_list_for_node(nacl, se_tpg);
521 void target_put_nacl(struct se_node_acl *nacl)
523 kref_put(&nacl->acl_kref, target_complete_nacl);
525 EXPORT_SYMBOL(target_put_nacl);
527 void transport_deregister_session_configfs(struct se_session *se_sess)
529 struct se_node_acl *se_nacl;
532 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
534 se_nacl = se_sess->se_node_acl;
536 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
537 if (!list_empty(&se_sess->sess_acl_list))
538 list_del_init(&se_sess->sess_acl_list);
540 * If the session list is empty, then clear the pointer.
541 * Otherwise, set the struct se_session pointer from the tail
542 * element of the per struct se_node_acl active session list.
544 if (list_empty(&se_nacl->acl_sess_list))
545 se_nacl->nacl_sess = NULL;
547 se_nacl->nacl_sess = container_of(
548 se_nacl->acl_sess_list.prev,
549 struct se_session, sess_acl_list);
551 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
554 EXPORT_SYMBOL(transport_deregister_session_configfs);
556 void transport_free_session(struct se_session *se_sess)
558 struct se_node_acl *se_nacl = se_sess->se_node_acl;
561 * Drop the se_node_acl->nacl_kref obtained from within
562 * core_tpg_get_initiator_node_acl().
565 struct se_portal_group *se_tpg = se_nacl->se_tpg;
566 const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
569 se_sess->se_node_acl = NULL;
572 * Also determine if we need to drop the extra ->cmd_kref if
573 * it had been previously dynamically generated, and
574 * the endpoint is not caching dynamic ACLs.
576 mutex_lock(&se_tpg->acl_node_mutex);
577 if (se_nacl->dynamic_node_acl &&
578 !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
579 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
580 if (list_empty(&se_nacl->acl_sess_list))
581 se_nacl->dynamic_stop = true;
582 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
584 if (se_nacl->dynamic_stop)
585 list_del_init(&se_nacl->acl_list);
587 mutex_unlock(&se_tpg->acl_node_mutex);
589 if (se_nacl->dynamic_stop)
590 target_put_nacl(se_nacl);
592 target_put_nacl(se_nacl);
594 if (se_sess->sess_cmd_map) {
595 sbitmap_queue_free(&se_sess->sess_tag_pool);
596 kvfree(se_sess->sess_cmd_map);
598 percpu_ref_exit(&se_sess->cmd_count);
599 kmem_cache_free(se_sess_cache, se_sess);
601 EXPORT_SYMBOL(transport_free_session);
603 void transport_deregister_session(struct se_session *se_sess)
605 struct se_portal_group *se_tpg = se_sess->se_tpg;
609 transport_free_session(se_sess);
613 spin_lock_irqsave(&se_tpg->session_lock, flags);
614 list_del(&se_sess->sess_list);
615 se_sess->se_tpg = NULL;
616 se_sess->fabric_sess_ptr = NULL;
617 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
619 pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
620 se_tpg->se_tpg_tfo->get_fabric_name());
622 * If last kref is dropping now for an explicit NodeACL, awake sleeping
623 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
624 * removal context from within transport_free_session() code.
626 * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
627 * to release all remaining generate_node_acl=1 created ACL resources.
630 transport_free_session(se_sess);
632 EXPORT_SYMBOL(transport_deregister_session);
634 void target_remove_session(struct se_session *se_sess)
636 transport_deregister_session_configfs(se_sess);
637 transport_deregister_session(se_sess);
639 EXPORT_SYMBOL(target_remove_session);
641 static void target_remove_from_state_list(struct se_cmd *cmd)
643 struct se_device *dev = cmd->se_dev;
649 spin_lock_irqsave(&dev->execute_task_lock, flags);
650 if (cmd->state_active) {
651 list_del(&cmd->state_list);
652 cmd->state_active = false;
654 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
658 * This function is called by the target core after the target core has
659 * finished processing a SCSI command or SCSI TMF. Both the regular command
660 * processing code and the code for aborting commands can call this
661 * function. CMD_T_STOP is set if and only if another thread is waiting
662 * inside transport_wait_for_tasks() for t_transport_stop_comp.
664 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
668 target_remove_from_state_list(cmd);
671 * Clear struct se_cmd->se_lun before the handoff to FE.
675 spin_lock_irqsave(&cmd->t_state_lock, flags);
677 * Determine if frontend context caller is requesting the stopping of
678 * this command for frontend exceptions.
680 if (cmd->transport_state & CMD_T_STOP) {
681 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
682 __func__, __LINE__, cmd->tag);
684 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
686 complete_all(&cmd->t_transport_stop_comp);
689 cmd->transport_state &= ~CMD_T_ACTIVE;
690 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
693 * Some fabric modules like tcm_loop can release their internally
694 * allocated I/O reference and struct se_cmd now.
696 * Fabric modules are expected to return '1' here if the se_cmd being
697 * passed is released at this point, or zero if not being released.
699 return cmd->se_tfo->check_stop_free(cmd);
702 static void transport_lun_remove_cmd(struct se_cmd *cmd)
704 struct se_lun *lun = cmd->se_lun;
709 if (cmpxchg(&cmd->lun_ref_active, true, false))
710 percpu_ref_put(&lun->lun_ref);
713 int transport_cmd_finish_abort(struct se_cmd *cmd)
715 bool send_tas = cmd->transport_state & CMD_T_TAS;
716 bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF);
720 transport_send_task_abort(cmd);
722 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
723 transport_lun_remove_cmd(cmd);
725 * Allow the fabric driver to unmap any resources before
726 * releasing the descriptor via TFO->release_cmd()
729 cmd->se_tfo->aborted_task(cmd);
731 if (transport_cmd_check_stop_to_fabric(cmd))
733 if (!send_tas && ack_kref)
734 ret = target_put_sess_cmd(cmd);
739 static void target_complete_failure_work(struct work_struct *work)
741 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
743 transport_generic_request_failure(cmd,
744 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
748 * Used when asking transport to copy Sense Data from the underlying
749 * Linux/SCSI struct scsi_cmnd
751 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
753 struct se_device *dev = cmd->se_dev;
755 WARN_ON(!cmd->se_lun);
760 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
763 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
765 pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
766 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
767 return cmd->sense_buffer;
770 void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
772 unsigned char *cmd_sense_buf;
775 spin_lock_irqsave(&cmd->t_state_lock, flags);
776 cmd_sense_buf = transport_get_sense_buffer(cmd);
777 if (!cmd_sense_buf) {
778 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
782 cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
783 memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
784 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
786 EXPORT_SYMBOL(transport_copy_sense_to_cmd);
788 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
790 struct se_device *dev = cmd->se_dev;
794 cmd->scsi_status = scsi_status;
796 spin_lock_irqsave(&cmd->t_state_lock, flags);
797 switch (cmd->scsi_status) {
798 case SAM_STAT_CHECK_CONDITION:
799 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
810 * Check for case where an explicit ABORT_TASK has been received
811 * and transport_wait_for_tasks() will be waiting for completion..
813 if (cmd->transport_state & CMD_T_ABORTED ||
814 cmd->transport_state & CMD_T_STOP) {
815 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
817 * If COMPARE_AND_WRITE was stopped by __transport_wait_for_tasks(),
818 * release se_device->caw_sem obtained by sbc_compare_and_write()
819 * since target_complete_ok_work() or target_complete_failure_work()
820 * won't be called to invoke the normal CAW completion callbacks.
822 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
825 complete_all(&cmd->t_transport_stop_comp);
827 } else if (!success) {
828 INIT_WORK(&cmd->work, target_complete_failure_work);
830 INIT_WORK(&cmd->work, target_complete_ok_work);
833 cmd->t_state = TRANSPORT_COMPLETE;
834 cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
835 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
837 if (cmd->se_cmd_flags & SCF_USE_CPUID)
838 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
840 queue_work(target_completion_wq, &cmd->work);
842 EXPORT_SYMBOL(target_complete_cmd);
844 void target_set_cmd_data_length(struct se_cmd *cmd, int length)
846 if (length < cmd->data_length) {
847 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
848 cmd->residual_count += cmd->data_length - length;
850 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
851 cmd->residual_count = cmd->data_length - length;
854 cmd->data_length = length;
857 EXPORT_SYMBOL(target_set_cmd_data_length);
859 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
861 if (scsi_status == SAM_STAT_GOOD ||
862 cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) {
863 target_set_cmd_data_length(cmd, length);
866 target_complete_cmd(cmd, scsi_status);
868 EXPORT_SYMBOL(target_complete_cmd_with_length);
870 static void target_add_to_state_list(struct se_cmd *cmd)
872 struct se_device *dev = cmd->se_dev;
875 spin_lock_irqsave(&dev->execute_task_lock, flags);
876 if (!cmd->state_active) {
877 list_add_tail(&cmd->state_list, &dev->state_list);
878 cmd->state_active = true;
880 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
884 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
886 static void transport_write_pending_qf(struct se_cmd *cmd);
887 static void transport_complete_qf(struct se_cmd *cmd);
889 void target_qf_do_work(struct work_struct *work)
891 struct se_device *dev = container_of(work, struct se_device,
893 LIST_HEAD(qf_cmd_list);
894 struct se_cmd *cmd, *cmd_tmp;
896 spin_lock_irq(&dev->qf_cmd_lock);
897 list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
898 spin_unlock_irq(&dev->qf_cmd_lock);
900 list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
901 list_del(&cmd->se_qf_node);
902 atomic_dec_mb(&dev->dev_qf_count);
904 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
905 " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
906 (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
907 (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
910 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
911 transport_write_pending_qf(cmd);
912 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
913 cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
914 transport_complete_qf(cmd);
918 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
920 switch (cmd->data_direction) {
923 case DMA_FROM_DEVICE:
927 case DMA_BIDIRECTIONAL:
936 void transport_dump_dev_state(
937 struct se_device *dev,
941 *bl += sprintf(b + *bl, "Status: ");
942 if (dev->export_count)
943 *bl += sprintf(b + *bl, "ACTIVATED");
945 *bl += sprintf(b + *bl, "DEACTIVATED");
947 *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
948 *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
949 dev->dev_attrib.block_size,
950 dev->dev_attrib.hw_max_sectors);
951 *bl += sprintf(b + *bl, " ");
954 void transport_dump_vpd_proto_id(
956 unsigned char *p_buf,
959 unsigned char buf[VPD_TMP_BUF_SIZE];
962 memset(buf, 0, VPD_TMP_BUF_SIZE);
963 len = sprintf(buf, "T10 VPD Protocol Identifier: ");
965 switch (vpd->protocol_identifier) {
967 sprintf(buf+len, "Fibre Channel\n");
970 sprintf(buf+len, "Parallel SCSI\n");
973 sprintf(buf+len, "SSA\n");
976 sprintf(buf+len, "IEEE 1394\n");
979 sprintf(buf+len, "SCSI Remote Direct Memory Access"
983 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
986 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
989 sprintf(buf+len, "Automation/Drive Interface Transport"
993 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
996 sprintf(buf+len, "Unknown 0x%02x\n",
997 vpd->protocol_identifier);
1002 strncpy(p_buf, buf, p_buf_len);
1004 pr_debug("%s", buf);
1008 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1011 * Check if the Protocol Identifier Valid (PIV) bit is set..
1013 * from spc3r23.pdf section 7.5.1
1015 if (page_83[1] & 0x80) {
1016 vpd->protocol_identifier = (page_83[0] & 0xf0);
1017 vpd->protocol_identifier_set = 1;
1018 transport_dump_vpd_proto_id(vpd, NULL, 0);
1021 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1023 int transport_dump_vpd_assoc(
1024 struct t10_vpd *vpd,
1025 unsigned char *p_buf,
1028 unsigned char buf[VPD_TMP_BUF_SIZE];
1032 memset(buf, 0, VPD_TMP_BUF_SIZE);
1033 len = sprintf(buf, "T10 VPD Identifier Association: ");
1035 switch (vpd->association) {
1037 sprintf(buf+len, "addressed logical unit\n");
1040 sprintf(buf+len, "target port\n");
1043 sprintf(buf+len, "SCSI target device\n");
1046 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1052 strncpy(p_buf, buf, p_buf_len);
1054 pr_debug("%s", buf);
1059 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1062 * The VPD identification association..
1064 * from spc3r23.pdf Section 7.6.3.1 Table 297
1066 vpd->association = (page_83[1] & 0x30);
1067 return transport_dump_vpd_assoc(vpd, NULL, 0);
1069 EXPORT_SYMBOL(transport_set_vpd_assoc);
1071 int transport_dump_vpd_ident_type(
1072 struct t10_vpd *vpd,
1073 unsigned char *p_buf,
1076 unsigned char buf[VPD_TMP_BUF_SIZE];
1080 memset(buf, 0, VPD_TMP_BUF_SIZE);
1081 len = sprintf(buf, "T10 VPD Identifier Type: ");
1083 switch (vpd->device_identifier_type) {
1085 sprintf(buf+len, "Vendor specific\n");
1088 sprintf(buf+len, "T10 Vendor ID based\n");
1091 sprintf(buf+len, "EUI-64 based\n");
1094 sprintf(buf+len, "NAA\n");
1097 sprintf(buf+len, "Relative target port identifier\n");
1100 sprintf(buf+len, "SCSI name string\n");
1103 sprintf(buf+len, "Unsupported: 0x%02x\n",
1104 vpd->device_identifier_type);
1110 if (p_buf_len < strlen(buf)+1)
1112 strncpy(p_buf, buf, p_buf_len);
1114 pr_debug("%s", buf);
1120 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1123 * The VPD identifier type..
1125 * from spc3r23.pdf Section 7.6.3.1 Table 298
1127 vpd->device_identifier_type = (page_83[1] & 0x0f);
1128 return transport_dump_vpd_ident_type(vpd, NULL, 0);
1130 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1132 int transport_dump_vpd_ident(
1133 struct t10_vpd *vpd,
1134 unsigned char *p_buf,
1137 unsigned char buf[VPD_TMP_BUF_SIZE];
1140 memset(buf, 0, VPD_TMP_BUF_SIZE);
1142 switch (vpd->device_identifier_code_set) {
1143 case 0x01: /* Binary */
1144 snprintf(buf, sizeof(buf),
1145 "T10 VPD Binary Device Identifier: %s\n",
1146 &vpd->device_identifier[0]);
1148 case 0x02: /* ASCII */
1149 snprintf(buf, sizeof(buf),
1150 "T10 VPD ASCII Device Identifier: %s\n",
1151 &vpd->device_identifier[0]);
1153 case 0x03: /* UTF-8 */
1154 snprintf(buf, sizeof(buf),
1155 "T10 VPD UTF-8 Device Identifier: %s\n",
1156 &vpd->device_identifier[0]);
1159 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1160 " 0x%02x", vpd->device_identifier_code_set);
1166 strncpy(p_buf, buf, p_buf_len);
1168 pr_debug("%s", buf);
1174 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1176 static const char hex_str[] = "0123456789abcdef";
1177 int j = 0, i = 4; /* offset to start of the identifier */
1180 * The VPD Code Set (encoding)
1182 * from spc3r23.pdf Section 7.6.3.1 Table 296
1184 vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1185 switch (vpd->device_identifier_code_set) {
1186 case 0x01: /* Binary */
1187 vpd->device_identifier[j++] =
1188 hex_str[vpd->device_identifier_type];
1189 while (i < (4 + page_83[3])) {
1190 vpd->device_identifier[j++] =
1191 hex_str[(page_83[i] & 0xf0) >> 4];
1192 vpd->device_identifier[j++] =
1193 hex_str[page_83[i] & 0x0f];
1197 case 0x02: /* ASCII */
1198 case 0x03: /* UTF-8 */
1199 while (i < (4 + page_83[3]))
1200 vpd->device_identifier[j++] = page_83[i++];
1206 return transport_dump_vpd_ident(vpd, NULL, 0);
1208 EXPORT_SYMBOL(transport_set_vpd_ident);
1210 static sense_reason_t
1211 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1216 if (!cmd->se_tfo->max_data_sg_nents)
1217 return TCM_NO_SENSE;
1219 * Check if fabric enforced maximum SGL entries per I/O descriptor
1220 * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT +
1221 * residual_count and reduce original cmd->data_length to maximum
1222 * length based on single PAGE_SIZE entry scatter-lists.
1224 mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1225 if (cmd->data_length > mtl) {
1227 * If an existing CDB overflow is present, calculate new residual
1228 * based on CDB size minus fabric maximum transfer length.
1230 * If an existing CDB underflow is present, calculate new residual
1231 * based on original cmd->data_length minus fabric maximum transfer
1234 * Otherwise, set the underflow residual based on cmd->data_length
1235 * minus fabric maximum transfer length.
1237 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1238 cmd->residual_count = (size - mtl);
1239 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1240 u32 orig_dl = size + cmd->residual_count;
1241 cmd->residual_count = (orig_dl - mtl);
1243 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1244 cmd->residual_count = (cmd->data_length - mtl);
1246 cmd->data_length = mtl;
1248 * Reset sbc_check_prot() calculated protection payload
1249 * length based upon the new smaller MTL.
1251 if (cmd->prot_length) {
1252 u32 sectors = (mtl / dev->dev_attrib.block_size);
1253 cmd->prot_length = dev->prot_length * sectors;
1256 return TCM_NO_SENSE;
1260 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1262 struct se_device *dev = cmd->se_dev;
1264 if (cmd->unknown_data_length) {
1265 cmd->data_length = size;
1266 } else if (size != cmd->data_length) {
1267 pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1268 " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1269 " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1270 cmd->data_length, size, cmd->t_task_cdb[0]);
1272 if (cmd->data_direction == DMA_TO_DEVICE) {
1273 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1274 pr_err_ratelimited("Rejecting underflow/overflow"
1275 " for WRITE data CDB\n");
1276 return TCM_INVALID_CDB_FIELD;
1279 * Some fabric drivers like iscsi-target still expect to
1280 * always reject overflow writes. Reject this case until
1281 * full fabric driver level support for overflow writes
1282 * is introduced tree-wide.
1284 if (size > cmd->data_length) {
1285 pr_err_ratelimited("Rejecting overflow for"
1286 " WRITE control CDB\n");
1287 return TCM_INVALID_CDB_FIELD;
1291 * Reject READ_* or WRITE_* with overflow/underflow for
1292 * type SCF_SCSI_DATA_CDB.
1294 if (dev->dev_attrib.block_size != 512) {
1295 pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1296 " CDB on non 512-byte sector setup subsystem"
1297 " plugin: %s\n", dev->transport->name);
1298 /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1299 return TCM_INVALID_CDB_FIELD;
1302 * For the overflow case keep the existing fabric provided
1303 * ->data_length. Otherwise for the underflow case, reset
1304 * ->data_length to the smaller SCSI expected data transfer
1307 if (size > cmd->data_length) {
1308 cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1309 cmd->residual_count = (size - cmd->data_length);
1311 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1312 cmd->residual_count = (cmd->data_length - size);
1313 cmd->data_length = size;
1317 return target_check_max_data_sg_nents(cmd, dev, size);
1322 * Used by fabric modules containing a local struct se_cmd within their
1323 * fabric dependent per I/O descriptor.
1325 * Preserves the value of @cmd->tag.
1327 void transport_init_se_cmd(
1329 const struct target_core_fabric_ops *tfo,
1330 struct se_session *se_sess,
1334 unsigned char *sense_buffer)
1336 INIT_LIST_HEAD(&cmd->se_delayed_node);
1337 INIT_LIST_HEAD(&cmd->se_qf_node);
1338 INIT_LIST_HEAD(&cmd->se_cmd_list);
1339 INIT_LIST_HEAD(&cmd->state_list);
1340 init_completion(&cmd->t_transport_stop_comp);
1342 spin_lock_init(&cmd->t_state_lock);
1343 INIT_WORK(&cmd->work, NULL);
1344 kref_init(&cmd->cmd_kref);
1347 cmd->se_sess = se_sess;
1348 cmd->data_length = data_length;
1349 cmd->data_direction = data_direction;
1350 cmd->sam_task_attr = task_attr;
1351 cmd->sense_buffer = sense_buffer;
1353 cmd->state_active = false;
1355 EXPORT_SYMBOL(transport_init_se_cmd);
1357 static sense_reason_t
1358 transport_check_alloc_task_attr(struct se_cmd *cmd)
1360 struct se_device *dev = cmd->se_dev;
1363 * Check if SAM Task Attribute emulation is enabled for this
1364 * struct se_device storage object
1366 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1369 if (cmd->sam_task_attr == TCM_ACA_TAG) {
1370 pr_debug("SAM Task Attribute ACA"
1371 " emulation is not supported\n");
1372 return TCM_INVALID_CDB_FIELD;
1379 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1381 struct se_device *dev = cmd->se_dev;
1385 * Ensure that the received CDB is less than the max (252 + 8) bytes
1386 * for VARIABLE_LENGTH_CMD
1388 if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1389 pr_err("Received SCSI CDB with command_size: %d that"
1390 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1391 scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1392 return TCM_INVALID_CDB_FIELD;
1395 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1396 * allocate the additional extended CDB buffer now.. Otherwise
1397 * setup the pointer from __t_task_cdb to t_task_cdb.
1399 if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1400 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1402 if (!cmd->t_task_cdb) {
1403 pr_err("Unable to allocate cmd->t_task_cdb"
1404 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1405 scsi_command_size(cdb),
1406 (unsigned long)sizeof(cmd->__t_task_cdb));
1407 return TCM_OUT_OF_RESOURCES;
1410 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1412 * Copy the original CDB into cmd->
1414 memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1416 trace_target_sequencer_start(cmd);
1418 ret = dev->transport->parse_cdb(cmd);
1419 if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1420 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1421 cmd->se_tfo->get_fabric_name(),
1422 cmd->se_sess->se_node_acl->initiatorname,
1423 cmd->t_task_cdb[0]);
1427 ret = transport_check_alloc_task_attr(cmd);
1431 cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1432 atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1435 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1438 * Used by fabric module frontends to queue tasks directly.
1439 * May only be used from process context.
1441 int transport_handle_cdb_direct(
1448 pr_err("cmd->se_lun is NULL\n");
1451 if (in_interrupt()) {
1453 pr_err("transport_generic_handle_cdb cannot be called"
1454 " from interrupt context\n");
1458 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1459 * outstanding descriptors are handled correctly during shutdown via
1460 * transport_wait_for_tasks()
1462 * Also, we don't take cmd->t_state_lock here as we only expect
1463 * this to be called for initial descriptor submission.
1465 cmd->t_state = TRANSPORT_NEW_CMD;
1466 cmd->transport_state |= CMD_T_ACTIVE;
1469 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1470 * so follow TRANSPORT_NEW_CMD processing thread context usage
1471 * and call transport_generic_request_failure() if necessary..
1473 ret = transport_generic_new_cmd(cmd);
1475 transport_generic_request_failure(cmd, ret);
1478 EXPORT_SYMBOL(transport_handle_cdb_direct);
1481 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1482 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1484 if (!sgl || !sgl_count)
1488 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1489 * scatterlists already have been set to follow what the fabric
1490 * passes for the original expected data transfer length.
1492 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1493 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1494 " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1495 return TCM_INVALID_CDB_FIELD;
1498 cmd->t_data_sg = sgl;
1499 cmd->t_data_nents = sgl_count;
1500 cmd->t_bidi_data_sg = sgl_bidi;
1501 cmd->t_bidi_data_nents = sgl_bidi_count;
1503 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1508 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1509 * se_cmd + use pre-allocated SGL memory.
1511 * @se_cmd: command descriptor to submit
1512 * @se_sess: associated se_sess for endpoint
1513 * @cdb: pointer to SCSI CDB
1514 * @sense: pointer to SCSI sense buffer
1515 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1516 * @data_length: fabric expected data transfer length
1517 * @task_attr: SAM task attribute
1518 * @data_dir: DMA data direction
1519 * @flags: flags for command submission from target_sc_flags_tables
1520 * @sgl: struct scatterlist memory for unidirectional mapping
1521 * @sgl_count: scatterlist count for unidirectional mapping
1522 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1523 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1524 * @sgl_prot: struct scatterlist memory protection information
1525 * @sgl_prot_count: scatterlist count for protection information
1527 * Task tags are supported if the caller has set @se_cmd->tag.
1529 * Returns non zero to signal active I/O shutdown failure. All other
1530 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1531 * but still return zero here.
1533 * This may only be called from process context, and also currently
1534 * assumes internal allocation of fabric payload buffer by target-core.
1536 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1537 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1538 u32 data_length, int task_attr, int data_dir, int flags,
1539 struct scatterlist *sgl, u32 sgl_count,
1540 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1541 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1543 struct se_portal_group *se_tpg;
1547 se_tpg = se_sess->se_tpg;
1549 BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1550 BUG_ON(in_interrupt());
1552 * Initialize se_cmd for target operation. From this point
1553 * exceptions are handled by sending exception status via
1554 * target_core_fabric_ops->queue_status() callback
1556 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1557 data_length, data_dir, task_attr, sense);
1559 if (flags & TARGET_SCF_USE_CPUID)
1560 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1562 se_cmd->cpuid = WORK_CPU_UNBOUND;
1564 if (flags & TARGET_SCF_UNKNOWN_SIZE)
1565 se_cmd->unknown_data_length = 1;
1567 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1568 * se_sess->sess_cmd_list. A second kref_get here is necessary
1569 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1570 * kref_put() to happen during fabric packet acknowledgement.
1572 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1576 * Signal bidirectional data payloads to target-core
1578 if (flags & TARGET_SCF_BIDI_OP)
1579 se_cmd->se_cmd_flags |= SCF_BIDI;
1581 * Locate se_lun pointer and attach it to struct se_cmd
1583 rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1585 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1586 target_put_sess_cmd(se_cmd);
1590 rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1592 transport_generic_request_failure(se_cmd, rc);
1597 * Save pointers for SGLs containing protection information,
1600 if (sgl_prot_count) {
1601 se_cmd->t_prot_sg = sgl_prot;
1602 se_cmd->t_prot_nents = sgl_prot_count;
1603 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1607 * When a non zero sgl_count has been passed perform SGL passthrough
1608 * mapping for pre-allocated fabric memory instead of having target
1609 * core perform an internal SGL allocation..
1611 if (sgl_count != 0) {
1615 * A work-around for tcm_loop as some userspace code via
1616 * scsi-generic do not memset their associated read buffers,
1617 * so go ahead and do that here for type non-data CDBs. Also
1618 * note that this is currently guaranteed to be a single SGL
1619 * for this case by target core in target_setup_cmd_from_cdb()
1620 * -> transport_generic_cmd_sequencer().
1622 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1623 se_cmd->data_direction == DMA_FROM_DEVICE) {
1624 unsigned char *buf = NULL;
1627 buf = kmap(sg_page(sgl)) + sgl->offset;
1630 memset(buf, 0, sgl->length);
1631 kunmap(sg_page(sgl));
1635 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1636 sgl_bidi, sgl_bidi_count);
1638 transport_generic_request_failure(se_cmd, rc);
1644 * Check if we need to delay processing because of ALUA
1645 * Active/NonOptimized primary access state..
1647 core_alua_check_nonop_delay(se_cmd);
1649 transport_handle_cdb_direct(se_cmd);
1652 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1655 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1657 * @se_cmd: command descriptor to submit
1658 * @se_sess: associated se_sess for endpoint
1659 * @cdb: pointer to SCSI CDB
1660 * @sense: pointer to SCSI sense buffer
1661 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1662 * @data_length: fabric expected data transfer length
1663 * @task_attr: SAM task attribute
1664 * @data_dir: DMA data direction
1665 * @flags: flags for command submission from target_sc_flags_tables
1667 * Task tags are supported if the caller has set @se_cmd->tag.
1669 * Returns non zero to signal active I/O shutdown failure. All other
1670 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1671 * but still return zero here.
1673 * This may only be called from process context, and also currently
1674 * assumes internal allocation of fabric payload buffer by target-core.
1676 * It also assumes interal target core SGL memory allocation.
1678 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1679 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1680 u32 data_length, int task_attr, int data_dir, int flags)
1682 return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1683 unpacked_lun, data_length, task_attr, data_dir,
1684 flags, NULL, 0, NULL, 0, NULL, 0);
1686 EXPORT_SYMBOL(target_submit_cmd);
1688 static void target_complete_tmr_failure(struct work_struct *work)
1690 struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1692 se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1693 se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1695 transport_lun_remove_cmd(se_cmd);
1696 transport_cmd_check_stop_to_fabric(se_cmd);
1699 static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
1702 struct se_cmd *se_cmd;
1703 unsigned long flags;
1706 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
1707 list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
1708 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1711 if (se_cmd->tag == tag) {
1712 *unpacked_lun = se_cmd->orig_fe_lun;
1717 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
1723 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1726 * @se_cmd: command descriptor to submit
1727 * @se_sess: associated se_sess for endpoint
1728 * @sense: pointer to SCSI sense buffer
1729 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1730 * @fabric_tmr_ptr: fabric context for TMR req
1731 * @tm_type: Type of TM request
1732 * @gfp: gfp type for caller
1733 * @tag: referenced task tag for TMR_ABORT_TASK
1734 * @flags: submit cmd flags
1736 * Callable from all contexts.
1739 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1740 unsigned char *sense, u64 unpacked_lun,
1741 void *fabric_tmr_ptr, unsigned char tm_type,
1742 gfp_t gfp, u64 tag, int flags)
1744 struct se_portal_group *se_tpg;
1747 se_tpg = se_sess->se_tpg;
1750 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1751 0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1753 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1754 * allocation failure.
1756 ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1760 if (tm_type == TMR_ABORT_TASK)
1761 se_cmd->se_tmr_req->ref_task_tag = tag;
1763 /* See target_submit_cmd for commentary */
1764 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1766 core_tmr_release_req(se_cmd->se_tmr_req);
1770 * If this is ABORT_TASK with no explicit fabric provided LUN,
1771 * go ahead and search active session tags for a match to figure
1772 * out unpacked_lun for the original se_cmd.
1774 if (tm_type == TMR_ABORT_TASK && (flags & TARGET_SCF_LOOKUP_LUN_FROM_TAG)) {
1775 if (!target_lookup_lun_from_tag(se_sess, tag, &unpacked_lun))
1779 ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1783 transport_generic_handle_tmr(se_cmd);
1787 * For callback during failure handling, push this work off
1788 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1791 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1792 schedule_work(&se_cmd->work);
1795 EXPORT_SYMBOL(target_submit_tmr);
1798 * Handle SAM-esque emulation for generic transport request failures.
1800 void transport_generic_request_failure(struct se_cmd *cmd,
1801 sense_reason_t sense_reason)
1803 int ret = 0, post_ret = 0;
1805 pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
1807 target_show_cmd("-----[ ", cmd);
1810 * For SAM Task Attribute emulation for failed struct se_cmd
1812 transport_complete_task_attr(cmd);
1815 * Handle special case for COMPARE_AND_WRITE failure, where the
1816 * callback is expected to drop the per device ->caw_sem.
1818 if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1819 cmd->transport_complete_callback)
1820 cmd->transport_complete_callback(cmd, false, &post_ret);
1822 if (transport_check_aborted_status(cmd, 1))
1825 switch (sense_reason) {
1826 case TCM_NON_EXISTENT_LUN:
1827 case TCM_UNSUPPORTED_SCSI_OPCODE:
1828 case TCM_INVALID_CDB_FIELD:
1829 case TCM_INVALID_PARAMETER_LIST:
1830 case TCM_PARAMETER_LIST_LENGTH_ERROR:
1831 case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1832 case TCM_UNKNOWN_MODE_PAGE:
1833 case TCM_WRITE_PROTECTED:
1834 case TCM_ADDRESS_OUT_OF_RANGE:
1835 case TCM_CHECK_CONDITION_ABORT_CMD:
1836 case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1837 case TCM_CHECK_CONDITION_NOT_READY:
1838 case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1839 case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1840 case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1841 case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1842 case TCM_TOO_MANY_TARGET_DESCS:
1843 case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
1844 case TCM_TOO_MANY_SEGMENT_DESCS:
1845 case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
1847 case TCM_OUT_OF_RESOURCES:
1848 cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
1851 cmd->scsi_status = SAM_STAT_BUSY;
1853 case TCM_RESERVATION_CONFLICT:
1855 * No SENSE Data payload for this case, set SCSI Status
1856 * and queue the response to $FABRIC_MOD.
1858 * Uses linux/include/scsi/scsi.h SAM status codes defs
1860 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1862 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1863 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1866 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1869 cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1870 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1871 cmd->orig_fe_lun, 0x2C,
1872 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1877 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1878 cmd->t_task_cdb[0], sense_reason);
1879 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1883 ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1888 transport_lun_remove_cmd(cmd);
1889 transport_cmd_check_stop_to_fabric(cmd);
1893 trace_target_cmd_complete(cmd);
1894 ret = cmd->se_tfo->queue_status(cmd);
1898 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
1900 EXPORT_SYMBOL(transport_generic_request_failure);
1902 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1906 if (!cmd->execute_cmd) {
1907 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1912 * Check for an existing UNIT ATTENTION condition after
1913 * target_handle_task_attr() has done SAM task attr
1914 * checking, and possibly have already defered execution
1915 * out to target_restart_delayed_cmds() context.
1917 ret = target_scsi3_ua_check(cmd);
1921 ret = target_alua_state_check(cmd);
1925 ret = target_check_reservation(cmd);
1927 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1932 ret = cmd->execute_cmd(cmd);
1936 spin_lock_irq(&cmd->t_state_lock);
1937 cmd->transport_state &= ~CMD_T_SENT;
1938 spin_unlock_irq(&cmd->t_state_lock);
1940 transport_generic_request_failure(cmd, ret);
1943 static int target_write_prot_action(struct se_cmd *cmd)
1947 * Perform WRITE_INSERT of PI using software emulation when backend
1948 * device has PI enabled, if the transport has not already generated
1949 * PI using hardware WRITE_INSERT offload.
1951 switch (cmd->prot_op) {
1952 case TARGET_PROT_DOUT_INSERT:
1953 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1954 sbc_dif_generate(cmd);
1956 case TARGET_PROT_DOUT_STRIP:
1957 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1960 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1961 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1962 sectors, 0, cmd->t_prot_sg, 0);
1963 if (unlikely(cmd->pi_err)) {
1964 spin_lock_irq(&cmd->t_state_lock);
1965 cmd->transport_state &= ~CMD_T_SENT;
1966 spin_unlock_irq(&cmd->t_state_lock);
1967 transport_generic_request_failure(cmd, cmd->pi_err);
1978 static bool target_handle_task_attr(struct se_cmd *cmd)
1980 struct se_device *dev = cmd->se_dev;
1982 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1985 cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
1988 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1989 * to allow the passed struct se_cmd list of tasks to the front of the list.
1991 switch (cmd->sam_task_attr) {
1993 atomic_inc_mb(&dev->non_ordered);
1994 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1995 cmd->t_task_cdb[0]);
1997 case TCM_ORDERED_TAG:
1998 atomic_inc_mb(&dev->delayed_cmd_count);
2000 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
2001 cmd->t_task_cdb[0]);
2005 * For SIMPLE and UNTAGGED Task Attribute commands
2007 atomic_inc_mb(&dev->non_ordered);
2009 if (atomic_read(&dev->delayed_cmd_count) == 0)
2014 if (cmd->sam_task_attr != TCM_ORDERED_TAG) {
2015 atomic_inc_mb(&dev->delayed_cmd_count);
2017 * We will account for this when we dequeue from the delayed
2020 atomic_dec_mb(&dev->non_ordered);
2023 spin_lock(&dev->delayed_cmd_lock);
2024 list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
2025 spin_unlock(&dev->delayed_cmd_lock);
2027 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
2028 cmd->t_task_cdb[0], cmd->sam_task_attr);
2030 * We may have no non ordered cmds when this function started or we
2031 * could have raced with the last simple/head cmd completing, so kick
2032 * the delayed handler here.
2034 schedule_work(&dev->delayed_cmd_work);
2038 static int __transport_check_aborted_status(struct se_cmd *, int);
2040 void target_execute_cmd(struct se_cmd *cmd)
2043 * Determine if frontend context caller is requesting the stopping of
2044 * this command for frontend exceptions.
2046 * If the received CDB has aleady been aborted stop processing it here.
2048 spin_lock_irq(&cmd->t_state_lock);
2049 if (__transport_check_aborted_status(cmd, 1)) {
2050 spin_unlock_irq(&cmd->t_state_lock);
2053 if (cmd->transport_state & CMD_T_STOP) {
2054 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2055 __func__, __LINE__, cmd->tag);
2057 spin_unlock_irq(&cmd->t_state_lock);
2058 complete_all(&cmd->t_transport_stop_comp);
2062 cmd->t_state = TRANSPORT_PROCESSING;
2063 cmd->transport_state &= ~CMD_T_PRE_EXECUTE;
2064 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
2065 spin_unlock_irq(&cmd->t_state_lock);
2067 if (target_write_prot_action(cmd))
2070 if (target_handle_task_attr(cmd)) {
2071 spin_lock_irq(&cmd->t_state_lock);
2072 cmd->transport_state &= ~CMD_T_SENT;
2073 spin_unlock_irq(&cmd->t_state_lock);
2077 __target_execute_cmd(cmd, true);
2079 EXPORT_SYMBOL(target_execute_cmd);
2082 * Process all commands up to the last received ORDERED task attribute which
2083 * requires another blocking boundary
2085 void target_do_delayed_work(struct work_struct *work)
2087 struct se_device *dev = container_of(work, struct se_device,
2090 spin_lock(&dev->delayed_cmd_lock);
2091 while (!dev->ordered_sync_in_progress) {
2094 if (list_empty(&dev->delayed_cmd_list))
2097 cmd = list_entry(dev->delayed_cmd_list.next,
2098 struct se_cmd, se_delayed_node);
2100 if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2102 * Check if we started with:
2103 * [ordered] [simple] [ordered]
2104 * and we are now at the last ordered so we have to wait
2105 * for the simple cmd.
2107 if (atomic_read(&dev->non_ordered) > 0)
2110 dev->ordered_sync_in_progress = true;
2113 list_del(&cmd->se_delayed_node);
2114 atomic_dec_mb(&dev->delayed_cmd_count);
2115 spin_unlock(&dev->delayed_cmd_lock);
2117 if (cmd->sam_task_attr != TCM_ORDERED_TAG)
2118 atomic_inc_mb(&dev->non_ordered);
2120 cmd->transport_state |= CMD_T_SENT;
2122 __target_execute_cmd(cmd, true);
2124 spin_lock(&dev->delayed_cmd_lock);
2126 spin_unlock(&dev->delayed_cmd_lock);
2130 * Called from I/O completion to determine which dormant/delayed
2131 * and ordered cmds need to have their tasks added to the execution queue.
2133 static void transport_complete_task_attr(struct se_cmd *cmd)
2135 struct se_device *dev = cmd->se_dev;
2137 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2140 if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2143 if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
2144 atomic_dec_mb(&dev->non_ordered);
2145 dev->dev_cur_ordered_id++;
2146 } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
2147 atomic_dec_mb(&dev->non_ordered);
2148 dev->dev_cur_ordered_id++;
2149 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
2150 dev->dev_cur_ordered_id);
2151 } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2152 spin_lock(&dev->delayed_cmd_lock);
2153 dev->ordered_sync_in_progress = false;
2154 spin_unlock(&dev->delayed_cmd_lock);
2156 dev->dev_cur_ordered_id++;
2157 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
2158 dev->dev_cur_ordered_id);
2160 cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2163 if (atomic_read(&dev->delayed_cmd_count) > 0)
2164 schedule_work(&dev->delayed_cmd_work);
2167 static void transport_complete_qf(struct se_cmd *cmd)
2171 transport_complete_task_attr(cmd);
2173 * If a fabric driver ->write_pending() or ->queue_data_in() callback
2174 * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2175 * the same callbacks should not be retried. Return CHECK_CONDITION
2176 * if a scsi_status is not already set.
2178 * If a fabric driver ->queue_status() has returned non zero, always
2179 * keep retrying no matter what..
2181 if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2182 if (cmd->scsi_status)
2185 translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2190 * Check if we need to send a sense buffer from
2191 * the struct se_cmd in question. We do NOT want
2192 * to take this path of the IO has been marked as
2193 * needing to be treated like a "normal read". This
2194 * is the case if it's a tape read, and either the
2195 * FM, EOM, or ILI bits are set, but there is no
2198 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2199 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2202 switch (cmd->data_direction) {
2203 case DMA_FROM_DEVICE:
2204 /* queue status if not treating this as a normal read */
2205 if (cmd->scsi_status &&
2206 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2209 trace_target_cmd_complete(cmd);
2210 ret = cmd->se_tfo->queue_data_in(cmd);
2213 if (cmd->se_cmd_flags & SCF_BIDI) {
2214 ret = cmd->se_tfo->queue_data_in(cmd);
2220 trace_target_cmd_complete(cmd);
2221 ret = cmd->se_tfo->queue_status(cmd);
2228 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2231 transport_lun_remove_cmd(cmd);
2232 transport_cmd_check_stop_to_fabric(cmd);
2235 static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2236 int err, bool write_pending)
2239 * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2240 * ->queue_data_in() callbacks from new process context.
2242 * Otherwise for other errors, transport_complete_qf() will send
2243 * CHECK_CONDITION via ->queue_status() instead of attempting to
2244 * retry associated fabric driver data-transfer callbacks.
2246 if (err == -EAGAIN || err == -ENOMEM) {
2247 cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2248 TRANSPORT_COMPLETE_QF_OK;
2250 pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2251 cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2254 spin_lock_irq(&dev->qf_cmd_lock);
2255 list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2256 atomic_inc_mb(&dev->dev_qf_count);
2257 spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2259 schedule_work(&cmd->se_dev->qf_work_queue);
2262 static bool target_read_prot_action(struct se_cmd *cmd)
2264 switch (cmd->prot_op) {
2265 case TARGET_PROT_DIN_STRIP:
2266 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2267 u32 sectors = cmd->data_length >>
2268 ilog2(cmd->se_dev->dev_attrib.block_size);
2270 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2271 sectors, 0, cmd->t_prot_sg,
2277 case TARGET_PROT_DIN_INSERT:
2278 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2281 sbc_dif_generate(cmd);
2290 static void target_complete_ok_work(struct work_struct *work)
2292 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2296 * Check if we need to move delayed/dormant tasks from cmds on the
2297 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2300 transport_complete_task_attr(cmd);
2303 * Check to schedule QUEUE_FULL work, or execute an existing
2304 * cmd->transport_qf_callback()
2306 if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2307 schedule_work(&cmd->se_dev->qf_work_queue);
2310 * Check if we need to send a sense buffer from
2311 * the struct se_cmd in question. We do NOT want
2312 * to take this path of the IO has been marked as
2313 * needing to be treated like a "normal read". This
2314 * is the case if it's a tape read, and either the
2315 * FM, EOM, or ILI bits are set, but there is no
2318 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2319 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2320 WARN_ON(!cmd->scsi_status);
2321 ret = transport_send_check_condition_and_sense(
2326 transport_lun_remove_cmd(cmd);
2327 transport_cmd_check_stop_to_fabric(cmd);
2331 * Check for a callback, used by amongst other things
2332 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2334 if (cmd->transport_complete_callback) {
2336 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2337 bool zero_dl = !(cmd->data_length);
2340 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2341 if (!rc && !post_ret) {
2347 ret = transport_send_check_condition_and_sense(cmd,
2352 transport_lun_remove_cmd(cmd);
2353 transport_cmd_check_stop_to_fabric(cmd);
2359 switch (cmd->data_direction) {
2360 case DMA_FROM_DEVICE:
2362 * if this is a READ-type IO, but SCSI status
2363 * is set, then skip returning data and just
2364 * return the status -- unless this IO is marked
2365 * as needing to be treated as a normal read,
2366 * in which case we want to go ahead and return
2367 * the data. This happens, for example, for tape
2368 * reads with the FM, EOM, or ILI bits set, with
2371 if (cmd->scsi_status &&
2372 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2375 atomic_long_add(cmd->data_length,
2376 &cmd->se_lun->lun_stats.tx_data_octets);
2378 * Perform READ_STRIP of PI using software emulation when
2379 * backend had PI enabled, if the transport will not be
2380 * performing hardware READ_STRIP offload.
2382 if (target_read_prot_action(cmd)) {
2383 ret = transport_send_check_condition_and_sense(cmd,
2388 transport_lun_remove_cmd(cmd);
2389 transport_cmd_check_stop_to_fabric(cmd);
2393 trace_target_cmd_complete(cmd);
2394 ret = cmd->se_tfo->queue_data_in(cmd);
2399 atomic_long_add(cmd->data_length,
2400 &cmd->se_lun->lun_stats.rx_data_octets);
2402 * Check if we need to send READ payload for BIDI-COMMAND
2404 if (cmd->se_cmd_flags & SCF_BIDI) {
2405 atomic_long_add(cmd->data_length,
2406 &cmd->se_lun->lun_stats.tx_data_octets);
2407 ret = cmd->se_tfo->queue_data_in(cmd);
2415 trace_target_cmd_complete(cmd);
2416 ret = cmd->se_tfo->queue_status(cmd);
2424 transport_lun_remove_cmd(cmd);
2425 transport_cmd_check_stop_to_fabric(cmd);
2429 pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2430 " data_direction: %d\n", cmd, cmd->data_direction);
2432 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2435 void target_free_sgl(struct scatterlist *sgl, int nents)
2437 sgl_free_n_order(sgl, nents, 0);
2439 EXPORT_SYMBOL(target_free_sgl);
2441 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2444 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2445 * emulation, and free + reset pointers if necessary..
2447 if (!cmd->t_data_sg_orig)
2450 kfree(cmd->t_data_sg);
2451 cmd->t_data_sg = cmd->t_data_sg_orig;
2452 cmd->t_data_sg_orig = NULL;
2453 cmd->t_data_nents = cmd->t_data_nents_orig;
2454 cmd->t_data_nents_orig = 0;
2457 static inline void transport_free_pages(struct se_cmd *cmd)
2459 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2460 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2461 cmd->t_prot_sg = NULL;
2462 cmd->t_prot_nents = 0;
2465 if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2467 * Release special case READ buffer payload required for
2468 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2470 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2471 target_free_sgl(cmd->t_bidi_data_sg,
2472 cmd->t_bidi_data_nents);
2473 cmd->t_bidi_data_sg = NULL;
2474 cmd->t_bidi_data_nents = 0;
2476 transport_reset_sgl_orig(cmd);
2479 transport_reset_sgl_orig(cmd);
2481 target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2482 cmd->t_data_sg = NULL;
2483 cmd->t_data_nents = 0;
2485 target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2486 cmd->t_bidi_data_sg = NULL;
2487 cmd->t_bidi_data_nents = 0;
2490 void *transport_kmap_data_sg(struct se_cmd *cmd)
2492 struct scatterlist *sg = cmd->t_data_sg;
2493 struct page **pages;
2497 * We need to take into account a possible offset here for fabrics like
2498 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2499 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2501 if (!cmd->t_data_nents)
2505 if (cmd->t_data_nents == 1)
2506 return kmap(sg_page(sg)) + sg->offset;
2508 /* >1 page. use vmap */
2509 pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2513 /* convert sg[] to pages[] */
2514 for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2515 pages[i] = sg_page(sg);
2518 cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
2520 if (!cmd->t_data_vmap)
2523 return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2525 EXPORT_SYMBOL(transport_kmap_data_sg);
2527 void transport_kunmap_data_sg(struct se_cmd *cmd)
2529 if (!cmd->t_data_nents) {
2531 } else if (cmd->t_data_nents == 1) {
2532 kunmap(sg_page(cmd->t_data_sg));
2536 vunmap(cmd->t_data_vmap);
2537 cmd->t_data_vmap = NULL;
2539 EXPORT_SYMBOL(transport_kunmap_data_sg);
2542 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2543 bool zero_page, bool chainable)
2545 gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2547 *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2548 return *sgl ? 0 : -ENOMEM;
2550 EXPORT_SYMBOL(target_alloc_sgl);
2553 * Allocate any required resources to execute the command. For writes we
2554 * might not have the payload yet, so notify the fabric via a call to
2555 * ->write_pending instead. Otherwise place it on the execution queue.
2558 transport_generic_new_cmd(struct se_cmd *cmd)
2560 unsigned long flags;
2562 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2564 if (cmd->prot_op != TARGET_PROT_NORMAL &&
2565 !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2566 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2567 cmd->prot_length, true, false);
2569 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2573 * Determine is the TCM fabric module has already allocated physical
2574 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2577 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2580 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2581 (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2584 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2585 bidi_length = cmd->t_task_nolb *
2586 cmd->se_dev->dev_attrib.block_size;
2588 bidi_length = cmd->data_length;
2590 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2591 &cmd->t_bidi_data_nents,
2592 bidi_length, zero_flag, false);
2594 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2597 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2598 cmd->data_length, zero_flag, false);
2600 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2601 } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2604 * Special case for COMPARE_AND_WRITE with fabrics
2605 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2607 u32 caw_length = cmd->t_task_nolb *
2608 cmd->se_dev->dev_attrib.block_size;
2610 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2611 &cmd->t_bidi_data_nents,
2612 caw_length, zero_flag, false);
2614 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2617 * If this command is not a write we can execute it right here,
2618 * for write buffers we need to notify the fabric driver first
2619 * and let it call back once the write buffers are ready.
2621 target_add_to_state_list(cmd);
2622 if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2623 target_execute_cmd(cmd);
2627 spin_lock_irqsave(&cmd->t_state_lock, flags);
2628 cmd->t_state = TRANSPORT_WRITE_PENDING;
2630 * Determine if frontend context caller is requesting the stopping of
2631 * this command for frontend exceptions.
2633 if (cmd->transport_state & CMD_T_STOP) {
2634 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2635 __func__, __LINE__, cmd->tag);
2637 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2639 complete_all(&cmd->t_transport_stop_comp);
2642 cmd->transport_state &= ~CMD_T_ACTIVE;
2643 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2645 ret = cmd->se_tfo->write_pending(cmd);
2652 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2653 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2656 EXPORT_SYMBOL(transport_generic_new_cmd);
2658 static void transport_write_pending_qf(struct se_cmd *cmd)
2660 unsigned long flags;
2664 spin_lock_irqsave(&cmd->t_state_lock, flags);
2665 stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2666 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2669 pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2670 __func__, __LINE__, cmd->tag);
2671 complete_all(&cmd->t_transport_stop_comp);
2675 ret = cmd->se_tfo->write_pending(cmd);
2677 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2679 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2684 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2685 unsigned long *flags);
2687 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2689 unsigned long flags;
2691 spin_lock_irqsave(&cmd->t_state_lock, flags);
2692 __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2693 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2697 * This function is called by frontend drivers after processing of a command
2700 * The protocol for ensuring that either the regular flow or the TMF
2701 * code drops one reference is as follows:
2702 * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
2703 * the frontend driver to drop one reference, synchronously or asynchronously.
2704 * - During regular command processing the target core sets CMD_T_COMPLETE
2705 * before invoking one of the .queue_*() functions.
2706 * - The code that aborts commands skips commands and TMFs for which
2707 * CMD_T_COMPLETE has been set.
2708 * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
2709 * commands that will be aborted.
2710 * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
2711 * transport_generic_free_cmd() skips its call to target_put_sess_cmd().
2712 * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
2713 * be called and will drop a reference.
2714 * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
2715 * will be called. transport_cmd_finish_abort() will drop the final reference.
2717 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2719 DECLARE_COMPLETION_ONSTACK(compl);
2721 bool aborted = false, tas = false;
2724 target_wait_free_cmd(cmd, &aborted, &tas);
2726 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
2728 * Handle WRITE failure case where transport_generic_new_cmd()
2729 * has already added se_cmd to state_list, but fabric has
2730 * failed command before I/O submission.
2732 if (cmd->state_active)
2733 target_remove_from_state_list(cmd);
2736 transport_lun_remove_cmd(cmd);
2739 cmd->compl = &compl;
2740 if (!aborted || tas)
2741 ret = target_put_sess_cmd(cmd);
2743 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2744 wait_for_completion(&compl);
2749 EXPORT_SYMBOL(transport_generic_free_cmd);
2752 * target_get_sess_cmd - Add command to active ->sess_cmd_list
2753 * @se_cmd: command descriptor to add
2754 * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
2756 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2758 struct se_session *se_sess = se_cmd->se_sess;
2759 unsigned long flags;
2763 * Add a second kref if the fabric caller is expecting to handle
2764 * fabric acknowledgement that requires two target_put_sess_cmd()
2765 * invocations before se_cmd descriptor release.
2768 if (!kref_get_unless_zero(&se_cmd->cmd_kref))
2771 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2774 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2775 if (se_sess->sess_tearing_down) {
2779 se_cmd->transport_state |= CMD_T_PRE_EXECUTE;
2780 list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2781 percpu_ref_get(&se_sess->cmd_count);
2783 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2785 if (ret && ack_kref)
2786 target_put_sess_cmd(se_cmd);
2790 EXPORT_SYMBOL(target_get_sess_cmd);
2792 static void target_free_cmd_mem(struct se_cmd *cmd)
2794 transport_free_pages(cmd);
2796 if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2797 core_tmr_release_req(cmd->se_tmr_req);
2798 if (cmd->t_task_cdb != cmd->__t_task_cdb)
2799 kfree(cmd->t_task_cdb);
2802 static void target_release_cmd_kref(struct kref *kref)
2804 struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2805 struct se_session *se_sess = se_cmd->se_sess;
2806 struct completion *compl = se_cmd->compl;
2807 unsigned long flags;
2810 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2811 list_del_init(&se_cmd->se_cmd_list);
2812 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2815 target_free_cmd_mem(se_cmd);
2816 se_cmd->se_tfo->release_cmd(se_cmd);
2820 percpu_ref_put(&se_sess->cmd_count);
2824 * target_put_sess_cmd - decrease the command reference count
2825 * @se_cmd: command to drop a reference from
2827 * Returns 1 if and only if this target_put_sess_cmd() call caused the
2828 * refcount to drop to zero. Returns zero otherwise.
2830 int target_put_sess_cmd(struct se_cmd *se_cmd)
2832 return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2834 EXPORT_SYMBOL(target_put_sess_cmd);
2836 static const char *data_dir_name(enum dma_data_direction d)
2839 case DMA_BIDIRECTIONAL: return "BIDI";
2840 case DMA_TO_DEVICE: return "WRITE";
2841 case DMA_FROM_DEVICE: return "READ";
2842 case DMA_NONE: return "NONE";
2848 static const char *cmd_state_name(enum transport_state_table t)
2851 case TRANSPORT_NO_STATE: return "NO_STATE";
2852 case TRANSPORT_NEW_CMD: return "NEW_CMD";
2853 case TRANSPORT_WRITE_PENDING: return "WRITE_PENDING";
2854 case TRANSPORT_PROCESSING: return "PROCESSING";
2855 case TRANSPORT_COMPLETE: return "COMPLETE";
2856 case TRANSPORT_ISTATE_PROCESSING:
2857 return "ISTATE_PROCESSING";
2858 case TRANSPORT_COMPLETE_QF_WP: return "COMPLETE_QF_WP";
2859 case TRANSPORT_COMPLETE_QF_OK: return "COMPLETE_QF_OK";
2860 case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR";
2866 static void target_append_str(char **str, const char *txt)
2870 *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
2871 kstrdup(txt, GFP_ATOMIC);
2876 * Convert a transport state bitmask into a string. The caller is
2877 * responsible for freeing the returned pointer.
2879 static char *target_ts_to_str(u32 ts)
2883 if (ts & CMD_T_ABORTED)
2884 target_append_str(&str, "aborted");
2885 if (ts & CMD_T_ACTIVE)
2886 target_append_str(&str, "active");
2887 if (ts & CMD_T_COMPLETE)
2888 target_append_str(&str, "complete");
2889 if (ts & CMD_T_SENT)
2890 target_append_str(&str, "sent");
2891 if (ts & CMD_T_STOP)
2892 target_append_str(&str, "stop");
2893 if (ts & CMD_T_FABRIC_STOP)
2894 target_append_str(&str, "fabric_stop");
2899 static const char *target_tmf_name(enum tcm_tmreq_table tmf)
2902 case TMR_ABORT_TASK: return "ABORT_TASK";
2903 case TMR_ABORT_TASK_SET: return "ABORT_TASK_SET";
2904 case TMR_CLEAR_ACA: return "CLEAR_ACA";
2905 case TMR_CLEAR_TASK_SET: return "CLEAR_TASK_SET";
2906 case TMR_LUN_RESET: return "LUN_RESET";
2907 case TMR_TARGET_WARM_RESET: return "TARGET_WARM_RESET";
2908 case TMR_TARGET_COLD_RESET: return "TARGET_COLD_RESET";
2909 case TMR_UNKNOWN: break;
2914 void target_show_cmd(const char *pfx, struct se_cmd *cmd)
2916 char *ts_str = target_ts_to_str(cmd->transport_state);
2917 const u8 *cdb = cmd->t_task_cdb;
2918 struct se_tmr_req *tmf = cmd->se_tmr_req;
2920 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2921 pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
2922 pfx, cdb[0], cdb[1], cmd->tag,
2923 data_dir_name(cmd->data_direction),
2924 cmd->se_tfo->get_cmd_state(cmd),
2925 cmd_state_name(cmd->t_state), cmd->data_length,
2926 kref_read(&cmd->cmd_kref), ts_str);
2928 pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
2929 pfx, target_tmf_name(tmf->function), cmd->tag,
2930 tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
2931 cmd_state_name(cmd->t_state),
2932 kref_read(&cmd->cmd_kref), ts_str);
2936 EXPORT_SYMBOL(target_show_cmd);
2939 * target_sess_cmd_list_set_waiting - Set sess_tearing_down so no new commands are queued.
2940 * @se_sess: session to flag
2942 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2944 unsigned long flags;
2946 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2947 se_sess->sess_tearing_down = 1;
2948 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2950 percpu_ref_kill(&se_sess->cmd_count);
2952 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2955 * target_wait_for_sess_cmds - Wait for outstanding commands
2956 * @se_sess: session to wait for active I/O
2958 void target_wait_for_sess_cmds(struct se_session *se_sess)
2963 WARN_ON_ONCE(!se_sess->sess_tearing_down);
2966 ret = wait_event_timeout(se_sess->cmd_list_wq,
2967 percpu_ref_is_zero(&se_sess->cmd_count),
2969 list_for_each_entry(cmd, &se_sess->sess_cmd_list, se_cmd_list)
2970 target_show_cmd("session shutdown: still waiting for ",
2974 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2976 static void target_lun_confirm(struct percpu_ref *ref)
2978 struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
2980 complete(&lun->lun_ref_comp);
2983 void transport_clear_lun_ref(struct se_lun *lun)
2986 * Mark the percpu-ref as DEAD, switch to atomic_t mode, drop
2987 * the initial reference and schedule confirm kill to be
2988 * executed after one full RCU grace period has completed.
2990 percpu_ref_kill_and_confirm(&lun->lun_ref, target_lun_confirm);
2992 * The first completion waits for percpu_ref_switch_to_atomic_rcu()
2993 * to call target_lun_confirm after lun->lun_ref has been marked
2994 * as __PERCPU_REF_DEAD on all CPUs, and switches to atomic_t
2995 * mode so that percpu_ref_tryget_live() lookup of lun->lun_ref
2996 * fails for all new incoming I/O.
2998 wait_for_completion(&lun->lun_ref_comp);
3000 * The second completion waits for percpu_ref_put_many() to
3001 * invoke ->release() after lun->lun_ref has switched to
3002 * atomic_t mode, and lun->lun_ref.count has reached zero.
3004 * At this point all target-core lun->lun_ref references have
3005 * been dropped via transport_lun_remove_cmd(), and it's safe
3006 * to proceed with the remaining LUN shutdown.
3008 wait_for_completion(&lun->lun_shutdown_comp);
3012 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
3013 bool *aborted, bool *tas, unsigned long *flags)
3014 __releases(&cmd->t_state_lock)
3015 __acquires(&cmd->t_state_lock)
3017 lockdep_assert_held(&cmd->t_state_lock);
3020 cmd->transport_state |= CMD_T_FABRIC_STOP;
3022 if (cmd->transport_state & CMD_T_ABORTED)
3025 if (cmd->transport_state & CMD_T_TAS)
3028 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
3029 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3032 if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
3033 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3036 if (!(cmd->transport_state & CMD_T_ACTIVE))
3039 if (fabric_stop && *aborted)
3042 cmd->transport_state |= CMD_T_STOP;
3044 target_show_cmd("wait_for_tasks: Stopping ", cmd);
3046 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
3048 while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
3050 target_show_cmd("wait for tasks: ", cmd);
3052 spin_lock_irqsave(&cmd->t_state_lock, *flags);
3053 cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
3055 pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
3056 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
3062 * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
3063 * @cmd: command to wait on
3065 bool transport_wait_for_tasks(struct se_cmd *cmd)
3067 unsigned long flags;
3068 bool ret, aborted = false, tas = false;
3070 spin_lock_irqsave(&cmd->t_state_lock, flags);
3071 ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
3072 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3076 EXPORT_SYMBOL(transport_wait_for_tasks);
3082 bool add_sector_info;
3085 static const struct sense_info sense_info_table[] = {
3089 [TCM_NON_EXISTENT_LUN] = {
3090 .key = ILLEGAL_REQUEST,
3091 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
3093 [TCM_UNSUPPORTED_SCSI_OPCODE] = {
3094 .key = ILLEGAL_REQUEST,
3095 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3097 [TCM_SECTOR_COUNT_TOO_MANY] = {
3098 .key = ILLEGAL_REQUEST,
3099 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3101 [TCM_UNKNOWN_MODE_PAGE] = {
3102 .key = ILLEGAL_REQUEST,
3103 .asc = 0x24, /* INVALID FIELD IN CDB */
3105 [TCM_CHECK_CONDITION_ABORT_CMD] = {
3106 .key = ABORTED_COMMAND,
3107 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3110 [TCM_INCORRECT_AMOUNT_OF_DATA] = {
3111 .key = ABORTED_COMMAND,
3112 .asc = 0x0c, /* WRITE ERROR */
3113 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3115 [TCM_INVALID_CDB_FIELD] = {
3116 .key = ILLEGAL_REQUEST,
3117 .asc = 0x24, /* INVALID FIELD IN CDB */
3119 [TCM_INVALID_PARAMETER_LIST] = {
3120 .key = ILLEGAL_REQUEST,
3121 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3123 [TCM_TOO_MANY_TARGET_DESCS] = {
3124 .key = ILLEGAL_REQUEST,
3126 .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3128 [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3129 .key = ILLEGAL_REQUEST,
3131 .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3133 [TCM_TOO_MANY_SEGMENT_DESCS] = {
3134 .key = ILLEGAL_REQUEST,
3136 .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3138 [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3139 .key = ILLEGAL_REQUEST,
3141 .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3143 [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3144 .key = ILLEGAL_REQUEST,
3145 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3147 [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3148 .key = ILLEGAL_REQUEST,
3149 .asc = 0x0c, /* WRITE ERROR */
3150 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3152 [TCM_SERVICE_CRC_ERROR] = {
3153 .key = ABORTED_COMMAND,
3154 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3155 .ascq = 0x05, /* N/A */
3157 [TCM_SNACK_REJECTED] = {
3158 .key = ABORTED_COMMAND,
3159 .asc = 0x11, /* READ ERROR */
3160 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3162 [TCM_WRITE_PROTECTED] = {
3163 .key = DATA_PROTECT,
3164 .asc = 0x27, /* WRITE PROTECTED */
3166 [TCM_ADDRESS_OUT_OF_RANGE] = {
3167 .key = ILLEGAL_REQUEST,
3168 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3170 [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3171 .key = UNIT_ATTENTION,
3173 [TCM_CHECK_CONDITION_NOT_READY] = {
3176 [TCM_MISCOMPARE_VERIFY] = {
3178 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3181 [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
3182 .key = ABORTED_COMMAND,
3184 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
3185 .add_sector_info = true,
3187 [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
3188 .key = ABORTED_COMMAND,
3190 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
3191 .add_sector_info = true,
3193 [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
3194 .key = ABORTED_COMMAND,
3196 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
3197 .add_sector_info = true,
3199 [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
3200 .key = COPY_ABORTED,
3202 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
3205 [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
3207 * Returning ILLEGAL REQUEST would cause immediate IO errors on
3208 * Solaris initiators. Returning NOT READY instead means the
3209 * operations will be retried a finite number of times and we
3210 * can survive intermittent errors.
3213 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
3215 [TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
3217 * From spc4r22 section5.7.7,5.7.8
3218 * If a PERSISTENT RESERVE OUT command with a REGISTER service action
3219 * or a REGISTER AND IGNORE EXISTING KEY service action or
3220 * REGISTER AND MOVE service actionis attempted,
3221 * but there are insufficient device server resources to complete the
3222 * operation, then the command shall be terminated with CHECK CONDITION
3223 * status, with the sense key set to ILLEGAL REQUEST,and the additonal
3224 * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
3226 .key = ILLEGAL_REQUEST,
3228 .ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
3233 * translate_sense_reason - translate a sense reason into T10 key, asc and ascq
3234 * @cmd: SCSI command in which the resulting sense buffer or SCSI status will
3236 * @reason: LIO sense reason code. If this argument has the value
3237 * TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If
3238 * dequeuing a unit attention fails due to multiple commands being processed
3239 * concurrently, set the command status to BUSY.
3241 * Return: 0 upon success or -EINVAL if the sense buffer is too small.
3243 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
3245 const struct sense_info *si;
3246 u8 *buffer = cmd->sense_buffer;
3247 int r = (__force int)reason;
3249 bool desc_format = target_sense_desc_format(cmd->se_dev);
3251 if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
3252 si = &sense_info_table[r];
3254 si = &sense_info_table[(__force int)
3255 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3258 if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
3259 if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc,
3261 cmd->scsi_status = SAM_STAT_BUSY;
3264 } else if (si->asc == 0) {
3265 WARN_ON_ONCE(cmd->scsi_asc == 0);
3266 asc = cmd->scsi_asc;
3267 ascq = cmd->scsi_ascq;
3273 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
3274 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
3275 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
3276 scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
3277 if (si->add_sector_info)
3278 WARN_ON_ONCE(scsi_set_sense_information(buffer,
3279 cmd->scsi_sense_length,
3280 cmd->bad_sector) < 0);
3284 transport_send_check_condition_and_sense(struct se_cmd *cmd,
3285 sense_reason_t reason, int from_transport)
3287 unsigned long flags;
3289 spin_lock_irqsave(&cmd->t_state_lock, flags);
3290 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
3291 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3294 cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
3295 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3297 if (!from_transport)
3298 translate_sense_reason(cmd, reason);
3300 trace_target_cmd_complete(cmd);
3301 return cmd->se_tfo->queue_status(cmd);
3303 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
3305 static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
3306 __releases(&cmd->t_state_lock)
3307 __acquires(&cmd->t_state_lock)
3311 assert_spin_locked(&cmd->t_state_lock);
3312 WARN_ON_ONCE(!irqs_disabled());
3314 if (!(cmd->transport_state & CMD_T_ABORTED))
3317 * If cmd has been aborted but either no status is to be sent or it has
3318 * already been sent, just return
3320 if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
3322 cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3326 pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
3327 " 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);
3329 cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
3330 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3331 trace_target_cmd_complete(cmd);
3333 spin_unlock_irq(&cmd->t_state_lock);
3334 ret = cmd->se_tfo->queue_status(cmd);
3336 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
3337 spin_lock_irq(&cmd->t_state_lock);
3342 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
3346 spin_lock_irq(&cmd->t_state_lock);
3347 ret = __transport_check_aborted_status(cmd, send_status);
3348 spin_unlock_irq(&cmd->t_state_lock);
3352 EXPORT_SYMBOL(transport_check_aborted_status);
3354 void transport_send_task_abort(struct se_cmd *cmd)
3356 unsigned long flags;
3359 spin_lock_irqsave(&cmd->t_state_lock, flags);
3360 if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
3361 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3364 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3367 * If there are still expected incoming fabric WRITEs, we wait
3368 * until until they have completed before sending a TASK_ABORTED
3369 * response. This response with TASK_ABORTED status will be
3370 * queued back to fabric module by transport_check_aborted_status().
3372 if (cmd->data_direction == DMA_TO_DEVICE) {
3373 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
3374 spin_lock_irqsave(&cmd->t_state_lock, flags);
3375 if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) {
3376 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3379 cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3380 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3385 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3387 transport_lun_remove_cmd(cmd);
3389 pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
3390 cmd->t_task_cdb[0], cmd->tag);
3392 trace_target_cmd_complete(cmd);
3393 ret = cmd->se_tfo->queue_status(cmd);
3395 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
3398 static void target_tmr_work(struct work_struct *work)
3400 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3401 struct se_device *dev = cmd->se_dev;
3402 struct se_tmr_req *tmr = cmd->se_tmr_req;
3403 unsigned long flags;
3406 spin_lock_irqsave(&cmd->t_state_lock, flags);
3407 if (cmd->transport_state & CMD_T_ABORTED) {
3408 tmr->response = TMR_FUNCTION_REJECTED;
3409 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3412 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3414 switch (tmr->function) {
3415 case TMR_ABORT_TASK:
3416 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3418 case TMR_ABORT_TASK_SET:
3420 case TMR_CLEAR_TASK_SET:
3421 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3424 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3425 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3426 TMR_FUNCTION_REJECTED;
3427 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3428 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3429 cmd->orig_fe_lun, 0x29,
3430 ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3433 case TMR_TARGET_WARM_RESET:
3434 tmr->response = TMR_FUNCTION_REJECTED;
3436 case TMR_TARGET_COLD_RESET:
3437 tmr->response = TMR_FUNCTION_REJECTED;
3440 pr_err("Unknown TMR function: 0x%02x.\n",
3442 tmr->response = TMR_FUNCTION_REJECTED;
3446 spin_lock_irqsave(&cmd->t_state_lock, flags);
3447 if (cmd->transport_state & CMD_T_ABORTED) {
3448 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3451 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3453 cmd->se_tfo->queue_tm_rsp(cmd);
3456 transport_lun_remove_cmd(cmd);
3457 transport_cmd_check_stop_to_fabric(cmd);
3460 int transport_generic_handle_tmr(
3463 unsigned long flags;
3464 bool aborted = false;
3466 spin_lock_irqsave(&cmd->t_state_lock, flags);
3467 if (cmd->transport_state & CMD_T_ABORTED) {
3470 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3471 cmd->transport_state |= CMD_T_ACTIVE;
3473 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3476 pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d"
3477 "ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function,
3478 cmd->se_tmr_req->ref_task_tag, cmd->tag);
3479 transport_lun_remove_cmd(cmd);
3480 transport_cmd_check_stop_to_fabric(cmd);
3484 INIT_WORK(&cmd->work, target_tmr_work);
3485 queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3488 EXPORT_SYMBOL(transport_generic_handle_tmr);
3491 target_check_wce(struct se_device *dev)
3495 if (dev->transport->get_write_cache)
3496 wce = dev->transport->get_write_cache(dev);
3497 else if (dev->dev_attrib.emulate_write_cache > 0)
3504 target_check_fua(struct se_device *dev)
3506 return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;