xref: /linux/drivers/target/target_core_transport.c (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
1 /*******************************************************************************
2  * Filename:  target_core_transport.c
3  *
4  * This file contains the Generic Target Engine Core.
5  *
6  * (c) Copyright 2002-2012 RisingTide Systems LLC.
7  *
8  * Nicholas A. Bellinger <nab@kernel.org>
9  *
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.
14  *
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.
19  *
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.
23  *
24  ******************************************************************************/
25 
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/blkdev.h>
32 #include <linux/spinlock.h>
33 #include <linux/kthread.h>
34 #include <linux/in.h>
35 #include <linux/cdrom.h>
36 #include <linux/module.h>
37 #include <linux/ratelimit.h>
38 #include <asm/unaligned.h>
39 #include <net/sock.h>
40 #include <net/tcp.h>
41 #include <scsi/scsi.h>
42 #include <scsi/scsi_cmnd.h>
43 #include <scsi/scsi_tcq.h>
44 
45 #include <target/target_core_base.h>
46 #include <target/target_core_backend.h>
47 #include <target/target_core_fabric.h>
48 #include <target/target_core_configfs.h>
49 
50 #include "target_core_internal.h"
51 #include "target_core_alua.h"
52 #include "target_core_pr.h"
53 #include "target_core_ua.h"
54 
55 static struct workqueue_struct *target_completion_wq;
56 static struct kmem_cache *se_sess_cache;
57 struct kmem_cache *se_ua_cache;
58 struct kmem_cache *t10_pr_reg_cache;
59 struct kmem_cache *t10_alua_lu_gp_cache;
60 struct kmem_cache *t10_alua_lu_gp_mem_cache;
61 struct kmem_cache *t10_alua_tg_pt_gp_cache;
62 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
63 
64 static void transport_complete_task_attr(struct se_cmd *cmd);
65 static void transport_handle_queue_full(struct se_cmd *cmd,
66 		struct se_device *dev);
67 static int transport_generic_get_mem(struct se_cmd *cmd);
68 static int target_get_sess_cmd(struct se_session *, struct se_cmd *, bool);
69 static void transport_put_cmd(struct se_cmd *cmd);
70 static void target_complete_ok_work(struct work_struct *work);
71 
72 int init_se_kmem_caches(void)
73 {
74 	se_sess_cache = kmem_cache_create("se_sess_cache",
75 			sizeof(struct se_session), __alignof__(struct se_session),
76 			0, NULL);
77 	if (!se_sess_cache) {
78 		pr_err("kmem_cache_create() for struct se_session"
79 				" failed\n");
80 		goto out;
81 	}
82 	se_ua_cache = kmem_cache_create("se_ua_cache",
83 			sizeof(struct se_ua), __alignof__(struct se_ua),
84 			0, NULL);
85 	if (!se_ua_cache) {
86 		pr_err("kmem_cache_create() for struct se_ua failed\n");
87 		goto out_free_sess_cache;
88 	}
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"
94 				" failed\n");
95 		goto out_free_ua_cache;
96 	}
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),
99 			0, NULL);
100 	if (!t10_alua_lu_gp_cache) {
101 		pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
102 				" failed\n");
103 		goto out_free_pr_reg_cache;
104 	}
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_"
110 				"cache failed\n");
111 		goto out_free_lu_gp_cache;
112 	}
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_"
118 				"cache failed\n");
119 		goto out_free_lu_gp_mem_cache;
120 	}
121 	t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
122 			"t10_alua_tg_pt_gp_mem_cache",
123 			sizeof(struct t10_alua_tg_pt_gp_member),
124 			__alignof__(struct t10_alua_tg_pt_gp_member),
125 			0, NULL);
126 	if (!t10_alua_tg_pt_gp_mem_cache) {
127 		pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
128 				"mem_t failed\n");
129 		goto out_free_tg_pt_gp_cache;
130 	}
131 
132 	target_completion_wq = alloc_workqueue("target_completion",
133 					       WQ_MEM_RECLAIM, 0);
134 	if (!target_completion_wq)
135 		goto out_free_tg_pt_gp_mem_cache;
136 
137 	return 0;
138 
139 out_free_tg_pt_gp_mem_cache:
140 	kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
141 out_free_tg_pt_gp_cache:
142 	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
143 out_free_lu_gp_mem_cache:
144 	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
145 out_free_lu_gp_cache:
146 	kmem_cache_destroy(t10_alua_lu_gp_cache);
147 out_free_pr_reg_cache:
148 	kmem_cache_destroy(t10_pr_reg_cache);
149 out_free_ua_cache:
150 	kmem_cache_destroy(se_ua_cache);
151 out_free_sess_cache:
152 	kmem_cache_destroy(se_sess_cache);
153 out:
154 	return -ENOMEM;
155 }
156 
157 void release_se_kmem_caches(void)
158 {
159 	destroy_workqueue(target_completion_wq);
160 	kmem_cache_destroy(se_sess_cache);
161 	kmem_cache_destroy(se_ua_cache);
162 	kmem_cache_destroy(t10_pr_reg_cache);
163 	kmem_cache_destroy(t10_alua_lu_gp_cache);
164 	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
165 	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
166 	kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
167 }
168 
169 /* This code ensures unique mib indexes are handed out. */
170 static DEFINE_SPINLOCK(scsi_mib_index_lock);
171 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
172 
173 /*
174  * Allocate a new row index for the entry type specified
175  */
176 u32 scsi_get_new_index(scsi_index_t type)
177 {
178 	u32 new_index;
179 
180 	BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
181 
182 	spin_lock(&scsi_mib_index_lock);
183 	new_index = ++scsi_mib_index[type];
184 	spin_unlock(&scsi_mib_index_lock);
185 
186 	return new_index;
187 }
188 
189 void transport_subsystem_check_init(void)
190 {
191 	int ret;
192 	static int sub_api_initialized;
193 
194 	if (sub_api_initialized)
195 		return;
196 
197 	ret = request_module("target_core_iblock");
198 	if (ret != 0)
199 		pr_err("Unable to load target_core_iblock\n");
200 
201 	ret = request_module("target_core_file");
202 	if (ret != 0)
203 		pr_err("Unable to load target_core_file\n");
204 
205 	ret = request_module("target_core_pscsi");
206 	if (ret != 0)
207 		pr_err("Unable to load target_core_pscsi\n");
208 
209 	sub_api_initialized = 1;
210 }
211 
212 struct se_session *transport_init_session(void)
213 {
214 	struct se_session *se_sess;
215 
216 	se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
217 	if (!se_sess) {
218 		pr_err("Unable to allocate struct se_session from"
219 				" se_sess_cache\n");
220 		return ERR_PTR(-ENOMEM);
221 	}
222 	INIT_LIST_HEAD(&se_sess->sess_list);
223 	INIT_LIST_HEAD(&se_sess->sess_acl_list);
224 	INIT_LIST_HEAD(&se_sess->sess_cmd_list);
225 	spin_lock_init(&se_sess->sess_cmd_lock);
226 	kref_init(&se_sess->sess_kref);
227 
228 	return se_sess;
229 }
230 EXPORT_SYMBOL(transport_init_session);
231 
232 /*
233  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
234  */
235 void __transport_register_session(
236 	struct se_portal_group *se_tpg,
237 	struct se_node_acl *se_nacl,
238 	struct se_session *se_sess,
239 	void *fabric_sess_ptr)
240 {
241 	unsigned char buf[PR_REG_ISID_LEN];
242 
243 	se_sess->se_tpg = se_tpg;
244 	se_sess->fabric_sess_ptr = fabric_sess_ptr;
245 	/*
246 	 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
247 	 *
248 	 * Only set for struct se_session's that will actually be moving I/O.
249 	 * eg: *NOT* discovery sessions.
250 	 */
251 	if (se_nacl) {
252 		/*
253 		 * If the fabric module supports an ISID based TransportID,
254 		 * save this value in binary from the fabric I_T Nexus now.
255 		 */
256 		if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
257 			memset(&buf[0], 0, PR_REG_ISID_LEN);
258 			se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
259 					&buf[0], PR_REG_ISID_LEN);
260 			se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
261 		}
262 		kref_get(&se_nacl->acl_kref);
263 
264 		spin_lock_irq(&se_nacl->nacl_sess_lock);
265 		/*
266 		 * The se_nacl->nacl_sess pointer will be set to the
267 		 * last active I_T Nexus for each struct se_node_acl.
268 		 */
269 		se_nacl->nacl_sess = se_sess;
270 
271 		list_add_tail(&se_sess->sess_acl_list,
272 			      &se_nacl->acl_sess_list);
273 		spin_unlock_irq(&se_nacl->nacl_sess_lock);
274 	}
275 	list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
276 
277 	pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
278 		se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
279 }
280 EXPORT_SYMBOL(__transport_register_session);
281 
282 void transport_register_session(
283 	struct se_portal_group *se_tpg,
284 	struct se_node_acl *se_nacl,
285 	struct se_session *se_sess,
286 	void *fabric_sess_ptr)
287 {
288 	unsigned long flags;
289 
290 	spin_lock_irqsave(&se_tpg->session_lock, flags);
291 	__transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
292 	spin_unlock_irqrestore(&se_tpg->session_lock, flags);
293 }
294 EXPORT_SYMBOL(transport_register_session);
295 
296 static void target_release_session(struct kref *kref)
297 {
298 	struct se_session *se_sess = container_of(kref,
299 			struct se_session, sess_kref);
300 	struct se_portal_group *se_tpg = se_sess->se_tpg;
301 
302 	se_tpg->se_tpg_tfo->close_session(se_sess);
303 }
304 
305 void target_get_session(struct se_session *se_sess)
306 {
307 	kref_get(&se_sess->sess_kref);
308 }
309 EXPORT_SYMBOL(target_get_session);
310 
311 void target_put_session(struct se_session *se_sess)
312 {
313 	struct se_portal_group *tpg = se_sess->se_tpg;
314 
315 	if (tpg->se_tpg_tfo->put_session != NULL) {
316 		tpg->se_tpg_tfo->put_session(se_sess);
317 		return;
318 	}
319 	kref_put(&se_sess->sess_kref, target_release_session);
320 }
321 EXPORT_SYMBOL(target_put_session);
322 
323 static void target_complete_nacl(struct kref *kref)
324 {
325 	struct se_node_acl *nacl = container_of(kref,
326 				struct se_node_acl, acl_kref);
327 
328 	complete(&nacl->acl_free_comp);
329 }
330 
331 void target_put_nacl(struct se_node_acl *nacl)
332 {
333 	kref_put(&nacl->acl_kref, target_complete_nacl);
334 }
335 
336 void transport_deregister_session_configfs(struct se_session *se_sess)
337 {
338 	struct se_node_acl *se_nacl;
339 	unsigned long flags;
340 	/*
341 	 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
342 	 */
343 	se_nacl = se_sess->se_node_acl;
344 	if (se_nacl) {
345 		spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
346 		if (se_nacl->acl_stop == 0)
347 			list_del(&se_sess->sess_acl_list);
348 		/*
349 		 * If the session list is empty, then clear the pointer.
350 		 * Otherwise, set the struct se_session pointer from the tail
351 		 * element of the per struct se_node_acl active session list.
352 		 */
353 		if (list_empty(&se_nacl->acl_sess_list))
354 			se_nacl->nacl_sess = NULL;
355 		else {
356 			se_nacl->nacl_sess = container_of(
357 					se_nacl->acl_sess_list.prev,
358 					struct se_session, sess_acl_list);
359 		}
360 		spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
361 	}
362 }
363 EXPORT_SYMBOL(transport_deregister_session_configfs);
364 
365 void transport_free_session(struct se_session *se_sess)
366 {
367 	kmem_cache_free(se_sess_cache, se_sess);
368 }
369 EXPORT_SYMBOL(transport_free_session);
370 
371 void transport_deregister_session(struct se_session *se_sess)
372 {
373 	struct se_portal_group *se_tpg = se_sess->se_tpg;
374 	struct target_core_fabric_ops *se_tfo;
375 	struct se_node_acl *se_nacl;
376 	unsigned long flags;
377 	bool comp_nacl = true;
378 
379 	if (!se_tpg) {
380 		transport_free_session(se_sess);
381 		return;
382 	}
383 	se_tfo = se_tpg->se_tpg_tfo;
384 
385 	spin_lock_irqsave(&se_tpg->session_lock, flags);
386 	list_del(&se_sess->sess_list);
387 	se_sess->se_tpg = NULL;
388 	se_sess->fabric_sess_ptr = NULL;
389 	spin_unlock_irqrestore(&se_tpg->session_lock, flags);
390 
391 	/*
392 	 * Determine if we need to do extra work for this initiator node's
393 	 * struct se_node_acl if it had been previously dynamically generated.
394 	 */
395 	se_nacl = se_sess->se_node_acl;
396 
397 	spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
398 	if (se_nacl && se_nacl->dynamic_node_acl) {
399 		if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
400 			list_del(&se_nacl->acl_list);
401 			se_tpg->num_node_acls--;
402 			spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
403 			core_tpg_wait_for_nacl_pr_ref(se_nacl);
404 			core_free_device_list_for_node(se_nacl, se_tpg);
405 			se_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
406 
407 			comp_nacl = false;
408 			spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
409 		}
410 	}
411 	spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
412 
413 	pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
414 		se_tpg->se_tpg_tfo->get_fabric_name());
415 	/*
416 	 * If last kref is dropping now for an explict NodeACL, awake sleeping
417 	 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
418 	 * removal context.
419 	 */
420 	if (se_nacl && comp_nacl == true)
421 		target_put_nacl(se_nacl);
422 
423 	transport_free_session(se_sess);
424 }
425 EXPORT_SYMBOL(transport_deregister_session);
426 
427 /*
428  * Called with cmd->t_state_lock held.
429  */
430 static void target_remove_from_state_list(struct se_cmd *cmd)
431 {
432 	struct se_device *dev = cmd->se_dev;
433 	unsigned long flags;
434 
435 	if (!dev)
436 		return;
437 
438 	if (cmd->transport_state & CMD_T_BUSY)
439 		return;
440 
441 	spin_lock_irqsave(&dev->execute_task_lock, flags);
442 	if (cmd->state_active) {
443 		list_del(&cmd->state_list);
444 		cmd->state_active = false;
445 	}
446 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
447 }
448 
449 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists)
450 {
451 	unsigned long flags;
452 
453 	spin_lock_irqsave(&cmd->t_state_lock, flags);
454 	/*
455 	 * Determine if IOCTL context caller in requesting the stopping of this
456 	 * command for LUN shutdown purposes.
457 	 */
458 	if (cmd->transport_state & CMD_T_LUN_STOP) {
459 		pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
460 			__func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
461 
462 		cmd->transport_state &= ~CMD_T_ACTIVE;
463 		if (remove_from_lists)
464 			target_remove_from_state_list(cmd);
465 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
466 
467 		complete(&cmd->transport_lun_stop_comp);
468 		return 1;
469 	}
470 
471 	if (remove_from_lists) {
472 		target_remove_from_state_list(cmd);
473 
474 		/*
475 		 * Clear struct se_cmd->se_lun before the handoff to FE.
476 		 */
477 		cmd->se_lun = NULL;
478 	}
479 
480 	/*
481 	 * Determine if frontend context caller is requesting the stopping of
482 	 * this command for frontend exceptions.
483 	 */
484 	if (cmd->transport_state & CMD_T_STOP) {
485 		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
486 			__func__, __LINE__,
487 			cmd->se_tfo->get_task_tag(cmd));
488 
489 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
490 
491 		complete(&cmd->t_transport_stop_comp);
492 		return 1;
493 	}
494 
495 	cmd->transport_state &= ~CMD_T_ACTIVE;
496 	if (remove_from_lists) {
497 		/*
498 		 * Some fabric modules like tcm_loop can release
499 		 * their internally allocated I/O reference now and
500 		 * struct se_cmd now.
501 		 *
502 		 * Fabric modules are expected to return '1' here if the
503 		 * se_cmd being passed is released at this point,
504 		 * or zero if not being released.
505 		 */
506 		if (cmd->se_tfo->check_stop_free != NULL) {
507 			spin_unlock_irqrestore(&cmd->t_state_lock, flags);
508 			return cmd->se_tfo->check_stop_free(cmd);
509 		}
510 	}
511 
512 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
513 	return 0;
514 }
515 
516 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
517 {
518 	return transport_cmd_check_stop(cmd, true);
519 }
520 
521 static void transport_lun_remove_cmd(struct se_cmd *cmd)
522 {
523 	struct se_lun *lun = cmd->se_lun;
524 	unsigned long flags;
525 
526 	if (!lun)
527 		return;
528 
529 	spin_lock_irqsave(&cmd->t_state_lock, flags);
530 	if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
531 		cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
532 		target_remove_from_state_list(cmd);
533 	}
534 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
535 
536 	spin_lock_irqsave(&lun->lun_cmd_lock, flags);
537 	if (!list_empty(&cmd->se_lun_node))
538 		list_del_init(&cmd->se_lun_node);
539 	spin_unlock_irqrestore(&lun->lun_cmd_lock, flags);
540 }
541 
542 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
543 {
544 	if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
545 		transport_lun_remove_cmd(cmd);
546 
547 	if (transport_cmd_check_stop_to_fabric(cmd))
548 		return;
549 	if (remove)
550 		transport_put_cmd(cmd);
551 }
552 
553 static void target_complete_failure_work(struct work_struct *work)
554 {
555 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
556 
557 	transport_generic_request_failure(cmd,
558 			TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
559 }
560 
561 /*
562  * Used when asking transport to copy Sense Data from the underlying
563  * Linux/SCSI struct scsi_cmnd
564  */
565 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
566 {
567 	struct se_device *dev = cmd->se_dev;
568 
569 	WARN_ON(!cmd->se_lun);
570 
571 	if (!dev)
572 		return NULL;
573 
574 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
575 		return NULL;
576 
577 	cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
578 
579 	pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
580 		dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
581 	return cmd->sense_buffer;
582 }
583 
584 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
585 {
586 	struct se_device *dev = cmd->se_dev;
587 	int success = scsi_status == GOOD;
588 	unsigned long flags;
589 
590 	cmd->scsi_status = scsi_status;
591 
592 
593 	spin_lock_irqsave(&cmd->t_state_lock, flags);
594 	cmd->transport_state &= ~CMD_T_BUSY;
595 
596 	if (dev && dev->transport->transport_complete) {
597 		dev->transport->transport_complete(cmd,
598 				cmd->t_data_sg,
599 				transport_get_sense_buffer(cmd));
600 		if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
601 			success = 1;
602 	}
603 
604 	/*
605 	 * See if we are waiting to complete for an exception condition.
606 	 */
607 	if (cmd->transport_state & CMD_T_REQUEST_STOP) {
608 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
609 		complete(&cmd->task_stop_comp);
610 		return;
611 	}
612 
613 	if (!success)
614 		cmd->transport_state |= CMD_T_FAILED;
615 
616 	/*
617 	 * Check for case where an explict ABORT_TASK has been received
618 	 * and transport_wait_for_tasks() will be waiting for completion..
619 	 */
620 	if (cmd->transport_state & CMD_T_ABORTED &&
621 	    cmd->transport_state & CMD_T_STOP) {
622 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
623 		complete(&cmd->t_transport_stop_comp);
624 		return;
625 	} else if (cmd->transport_state & CMD_T_FAILED) {
626 		INIT_WORK(&cmd->work, target_complete_failure_work);
627 	} else {
628 		INIT_WORK(&cmd->work, target_complete_ok_work);
629 	}
630 
631 	cmd->t_state = TRANSPORT_COMPLETE;
632 	cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
633 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
634 
635 	queue_work(target_completion_wq, &cmd->work);
636 }
637 EXPORT_SYMBOL(target_complete_cmd);
638 
639 static void target_add_to_state_list(struct se_cmd *cmd)
640 {
641 	struct se_device *dev = cmd->se_dev;
642 	unsigned long flags;
643 
644 	spin_lock_irqsave(&dev->execute_task_lock, flags);
645 	if (!cmd->state_active) {
646 		list_add_tail(&cmd->state_list, &dev->state_list);
647 		cmd->state_active = true;
648 	}
649 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
650 }
651 
652 /*
653  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
654  */
655 static void transport_write_pending_qf(struct se_cmd *cmd);
656 static void transport_complete_qf(struct se_cmd *cmd);
657 
658 void target_qf_do_work(struct work_struct *work)
659 {
660 	struct se_device *dev = container_of(work, struct se_device,
661 					qf_work_queue);
662 	LIST_HEAD(qf_cmd_list);
663 	struct se_cmd *cmd, *cmd_tmp;
664 
665 	spin_lock_irq(&dev->qf_cmd_lock);
666 	list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
667 	spin_unlock_irq(&dev->qf_cmd_lock);
668 
669 	list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
670 		list_del(&cmd->se_qf_node);
671 		atomic_dec(&dev->dev_qf_count);
672 		smp_mb__after_atomic_dec();
673 
674 		pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
675 			" context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
676 			(cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
677 			(cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
678 			: "UNKNOWN");
679 
680 		if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
681 			transport_write_pending_qf(cmd);
682 		else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
683 			transport_complete_qf(cmd);
684 	}
685 }
686 
687 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
688 {
689 	switch (cmd->data_direction) {
690 	case DMA_NONE:
691 		return "NONE";
692 	case DMA_FROM_DEVICE:
693 		return "READ";
694 	case DMA_TO_DEVICE:
695 		return "WRITE";
696 	case DMA_BIDIRECTIONAL:
697 		return "BIDI";
698 	default:
699 		break;
700 	}
701 
702 	return "UNKNOWN";
703 }
704 
705 void transport_dump_dev_state(
706 	struct se_device *dev,
707 	char *b,
708 	int *bl)
709 {
710 	*bl += sprintf(b + *bl, "Status: ");
711 	if (dev->export_count)
712 		*bl += sprintf(b + *bl, "ACTIVATED");
713 	else
714 		*bl += sprintf(b + *bl, "DEACTIVATED");
715 
716 	*bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
717 	*bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
718 		dev->dev_attrib.block_size,
719 		dev->dev_attrib.hw_max_sectors);
720 	*bl += sprintf(b + *bl, "        ");
721 }
722 
723 void transport_dump_vpd_proto_id(
724 	struct t10_vpd *vpd,
725 	unsigned char *p_buf,
726 	int p_buf_len)
727 {
728 	unsigned char buf[VPD_TMP_BUF_SIZE];
729 	int len;
730 
731 	memset(buf, 0, VPD_TMP_BUF_SIZE);
732 	len = sprintf(buf, "T10 VPD Protocol Identifier: ");
733 
734 	switch (vpd->protocol_identifier) {
735 	case 0x00:
736 		sprintf(buf+len, "Fibre Channel\n");
737 		break;
738 	case 0x10:
739 		sprintf(buf+len, "Parallel SCSI\n");
740 		break;
741 	case 0x20:
742 		sprintf(buf+len, "SSA\n");
743 		break;
744 	case 0x30:
745 		sprintf(buf+len, "IEEE 1394\n");
746 		break;
747 	case 0x40:
748 		sprintf(buf+len, "SCSI Remote Direct Memory Access"
749 				" Protocol\n");
750 		break;
751 	case 0x50:
752 		sprintf(buf+len, "Internet SCSI (iSCSI)\n");
753 		break;
754 	case 0x60:
755 		sprintf(buf+len, "SAS Serial SCSI Protocol\n");
756 		break;
757 	case 0x70:
758 		sprintf(buf+len, "Automation/Drive Interface Transport"
759 				" Protocol\n");
760 		break;
761 	case 0x80:
762 		sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
763 		break;
764 	default:
765 		sprintf(buf+len, "Unknown 0x%02x\n",
766 				vpd->protocol_identifier);
767 		break;
768 	}
769 
770 	if (p_buf)
771 		strncpy(p_buf, buf, p_buf_len);
772 	else
773 		pr_debug("%s", buf);
774 }
775 
776 void
777 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
778 {
779 	/*
780 	 * Check if the Protocol Identifier Valid (PIV) bit is set..
781 	 *
782 	 * from spc3r23.pdf section 7.5.1
783 	 */
784 	 if (page_83[1] & 0x80) {
785 		vpd->protocol_identifier = (page_83[0] & 0xf0);
786 		vpd->protocol_identifier_set = 1;
787 		transport_dump_vpd_proto_id(vpd, NULL, 0);
788 	}
789 }
790 EXPORT_SYMBOL(transport_set_vpd_proto_id);
791 
792 int transport_dump_vpd_assoc(
793 	struct t10_vpd *vpd,
794 	unsigned char *p_buf,
795 	int p_buf_len)
796 {
797 	unsigned char buf[VPD_TMP_BUF_SIZE];
798 	int ret = 0;
799 	int len;
800 
801 	memset(buf, 0, VPD_TMP_BUF_SIZE);
802 	len = sprintf(buf, "T10 VPD Identifier Association: ");
803 
804 	switch (vpd->association) {
805 	case 0x00:
806 		sprintf(buf+len, "addressed logical unit\n");
807 		break;
808 	case 0x10:
809 		sprintf(buf+len, "target port\n");
810 		break;
811 	case 0x20:
812 		sprintf(buf+len, "SCSI target device\n");
813 		break;
814 	default:
815 		sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
816 		ret = -EINVAL;
817 		break;
818 	}
819 
820 	if (p_buf)
821 		strncpy(p_buf, buf, p_buf_len);
822 	else
823 		pr_debug("%s", buf);
824 
825 	return ret;
826 }
827 
828 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
829 {
830 	/*
831 	 * The VPD identification association..
832 	 *
833 	 * from spc3r23.pdf Section 7.6.3.1 Table 297
834 	 */
835 	vpd->association = (page_83[1] & 0x30);
836 	return transport_dump_vpd_assoc(vpd, NULL, 0);
837 }
838 EXPORT_SYMBOL(transport_set_vpd_assoc);
839 
840 int transport_dump_vpd_ident_type(
841 	struct t10_vpd *vpd,
842 	unsigned char *p_buf,
843 	int p_buf_len)
844 {
845 	unsigned char buf[VPD_TMP_BUF_SIZE];
846 	int ret = 0;
847 	int len;
848 
849 	memset(buf, 0, VPD_TMP_BUF_SIZE);
850 	len = sprintf(buf, "T10 VPD Identifier Type: ");
851 
852 	switch (vpd->device_identifier_type) {
853 	case 0x00:
854 		sprintf(buf+len, "Vendor specific\n");
855 		break;
856 	case 0x01:
857 		sprintf(buf+len, "T10 Vendor ID based\n");
858 		break;
859 	case 0x02:
860 		sprintf(buf+len, "EUI-64 based\n");
861 		break;
862 	case 0x03:
863 		sprintf(buf+len, "NAA\n");
864 		break;
865 	case 0x04:
866 		sprintf(buf+len, "Relative target port identifier\n");
867 		break;
868 	case 0x08:
869 		sprintf(buf+len, "SCSI name string\n");
870 		break;
871 	default:
872 		sprintf(buf+len, "Unsupported: 0x%02x\n",
873 				vpd->device_identifier_type);
874 		ret = -EINVAL;
875 		break;
876 	}
877 
878 	if (p_buf) {
879 		if (p_buf_len < strlen(buf)+1)
880 			return -EINVAL;
881 		strncpy(p_buf, buf, p_buf_len);
882 	} else {
883 		pr_debug("%s", buf);
884 	}
885 
886 	return ret;
887 }
888 
889 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
890 {
891 	/*
892 	 * The VPD identifier type..
893 	 *
894 	 * from spc3r23.pdf Section 7.6.3.1 Table 298
895 	 */
896 	vpd->device_identifier_type = (page_83[1] & 0x0f);
897 	return transport_dump_vpd_ident_type(vpd, NULL, 0);
898 }
899 EXPORT_SYMBOL(transport_set_vpd_ident_type);
900 
901 int transport_dump_vpd_ident(
902 	struct t10_vpd *vpd,
903 	unsigned char *p_buf,
904 	int p_buf_len)
905 {
906 	unsigned char buf[VPD_TMP_BUF_SIZE];
907 	int ret = 0;
908 
909 	memset(buf, 0, VPD_TMP_BUF_SIZE);
910 
911 	switch (vpd->device_identifier_code_set) {
912 	case 0x01: /* Binary */
913 		sprintf(buf, "T10 VPD Binary Device Identifier: %s\n",
914 			&vpd->device_identifier[0]);
915 		break;
916 	case 0x02: /* ASCII */
917 		sprintf(buf, "T10 VPD ASCII Device Identifier: %s\n",
918 			&vpd->device_identifier[0]);
919 		break;
920 	case 0x03: /* UTF-8 */
921 		sprintf(buf, "T10 VPD UTF-8 Device Identifier: %s\n",
922 			&vpd->device_identifier[0]);
923 		break;
924 	default:
925 		sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
926 			" 0x%02x", vpd->device_identifier_code_set);
927 		ret = -EINVAL;
928 		break;
929 	}
930 
931 	if (p_buf)
932 		strncpy(p_buf, buf, p_buf_len);
933 	else
934 		pr_debug("%s", buf);
935 
936 	return ret;
937 }
938 
939 int
940 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
941 {
942 	static const char hex_str[] = "0123456789abcdef";
943 	int j = 0, i = 4; /* offset to start of the identifier */
944 
945 	/*
946 	 * The VPD Code Set (encoding)
947 	 *
948 	 * from spc3r23.pdf Section 7.6.3.1 Table 296
949 	 */
950 	vpd->device_identifier_code_set = (page_83[0] & 0x0f);
951 	switch (vpd->device_identifier_code_set) {
952 	case 0x01: /* Binary */
953 		vpd->device_identifier[j++] =
954 				hex_str[vpd->device_identifier_type];
955 		while (i < (4 + page_83[3])) {
956 			vpd->device_identifier[j++] =
957 				hex_str[(page_83[i] & 0xf0) >> 4];
958 			vpd->device_identifier[j++] =
959 				hex_str[page_83[i] & 0x0f];
960 			i++;
961 		}
962 		break;
963 	case 0x02: /* ASCII */
964 	case 0x03: /* UTF-8 */
965 		while (i < (4 + page_83[3]))
966 			vpd->device_identifier[j++] = page_83[i++];
967 		break;
968 	default:
969 		break;
970 	}
971 
972 	return transport_dump_vpd_ident(vpd, NULL, 0);
973 }
974 EXPORT_SYMBOL(transport_set_vpd_ident);
975 
976 sense_reason_t
977 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
978 {
979 	struct se_device *dev = cmd->se_dev;
980 
981 	if (cmd->unknown_data_length) {
982 		cmd->data_length = size;
983 	} else if (size != cmd->data_length) {
984 		pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
985 			" %u does not match SCSI CDB Length: %u for SAM Opcode:"
986 			" 0x%02x\n", cmd->se_tfo->get_fabric_name(),
987 				cmd->data_length, size, cmd->t_task_cdb[0]);
988 
989 		if (cmd->data_direction == DMA_TO_DEVICE) {
990 			pr_err("Rejecting underflow/overflow"
991 					" WRITE data\n");
992 			return TCM_INVALID_CDB_FIELD;
993 		}
994 		/*
995 		 * Reject READ_* or WRITE_* with overflow/underflow for
996 		 * type SCF_SCSI_DATA_CDB.
997 		 */
998 		if (dev->dev_attrib.block_size != 512)  {
999 			pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1000 				" CDB on non 512-byte sector setup subsystem"
1001 				" plugin: %s\n", dev->transport->name);
1002 			/* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1003 			return TCM_INVALID_CDB_FIELD;
1004 		}
1005 		/*
1006 		 * For the overflow case keep the existing fabric provided
1007 		 * ->data_length.  Otherwise for the underflow case, reset
1008 		 * ->data_length to the smaller SCSI expected data transfer
1009 		 * length.
1010 		 */
1011 		if (size > cmd->data_length) {
1012 			cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1013 			cmd->residual_count = (size - cmd->data_length);
1014 		} else {
1015 			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1016 			cmd->residual_count = (cmd->data_length - size);
1017 			cmd->data_length = size;
1018 		}
1019 	}
1020 
1021 	return 0;
1022 
1023 }
1024 
1025 /*
1026  * Used by fabric modules containing a local struct se_cmd within their
1027  * fabric dependent per I/O descriptor.
1028  */
1029 void transport_init_se_cmd(
1030 	struct se_cmd *cmd,
1031 	struct target_core_fabric_ops *tfo,
1032 	struct se_session *se_sess,
1033 	u32 data_length,
1034 	int data_direction,
1035 	int task_attr,
1036 	unsigned char *sense_buffer)
1037 {
1038 	INIT_LIST_HEAD(&cmd->se_lun_node);
1039 	INIT_LIST_HEAD(&cmd->se_delayed_node);
1040 	INIT_LIST_HEAD(&cmd->se_qf_node);
1041 	INIT_LIST_HEAD(&cmd->se_cmd_list);
1042 	INIT_LIST_HEAD(&cmd->state_list);
1043 	init_completion(&cmd->transport_lun_fe_stop_comp);
1044 	init_completion(&cmd->transport_lun_stop_comp);
1045 	init_completion(&cmd->t_transport_stop_comp);
1046 	init_completion(&cmd->cmd_wait_comp);
1047 	init_completion(&cmd->task_stop_comp);
1048 	spin_lock_init(&cmd->t_state_lock);
1049 	cmd->transport_state = CMD_T_DEV_ACTIVE;
1050 
1051 	cmd->se_tfo = tfo;
1052 	cmd->se_sess = se_sess;
1053 	cmd->data_length = data_length;
1054 	cmd->data_direction = data_direction;
1055 	cmd->sam_task_attr = task_attr;
1056 	cmd->sense_buffer = sense_buffer;
1057 
1058 	cmd->state_active = false;
1059 }
1060 EXPORT_SYMBOL(transport_init_se_cmd);
1061 
1062 static sense_reason_t
1063 transport_check_alloc_task_attr(struct se_cmd *cmd)
1064 {
1065 	struct se_device *dev = cmd->se_dev;
1066 
1067 	/*
1068 	 * Check if SAM Task Attribute emulation is enabled for this
1069 	 * struct se_device storage object
1070 	 */
1071 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1072 		return 0;
1073 
1074 	if (cmd->sam_task_attr == MSG_ACA_TAG) {
1075 		pr_debug("SAM Task Attribute ACA"
1076 			" emulation is not supported\n");
1077 		return TCM_INVALID_CDB_FIELD;
1078 	}
1079 	/*
1080 	 * Used to determine when ORDERED commands should go from
1081 	 * Dormant to Active status.
1082 	 */
1083 	cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1084 	smp_mb__after_atomic_inc();
1085 	pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1086 			cmd->se_ordered_id, cmd->sam_task_attr,
1087 			dev->transport->name);
1088 	return 0;
1089 }
1090 
1091 sense_reason_t
1092 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1093 {
1094 	struct se_device *dev = cmd->se_dev;
1095 	unsigned long flags;
1096 	sense_reason_t ret;
1097 
1098 	/*
1099 	 * Ensure that the received CDB is less than the max (252 + 8) bytes
1100 	 * for VARIABLE_LENGTH_CMD
1101 	 */
1102 	if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1103 		pr_err("Received SCSI CDB with command_size: %d that"
1104 			" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1105 			scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1106 		return TCM_INVALID_CDB_FIELD;
1107 	}
1108 	/*
1109 	 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1110 	 * allocate the additional extended CDB buffer now..  Otherwise
1111 	 * setup the pointer from __t_task_cdb to t_task_cdb.
1112 	 */
1113 	if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1114 		cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1115 						GFP_KERNEL);
1116 		if (!cmd->t_task_cdb) {
1117 			pr_err("Unable to allocate cmd->t_task_cdb"
1118 				" %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1119 				scsi_command_size(cdb),
1120 				(unsigned long)sizeof(cmd->__t_task_cdb));
1121 			return TCM_OUT_OF_RESOURCES;
1122 		}
1123 	} else
1124 		cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1125 	/*
1126 	 * Copy the original CDB into cmd->
1127 	 */
1128 	memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1129 
1130 	/*
1131 	 * Check for an existing UNIT ATTENTION condition
1132 	 */
1133 	ret = target_scsi3_ua_check(cmd);
1134 	if (ret)
1135 		return ret;
1136 
1137 	ret = target_alua_state_check(cmd);
1138 	if (ret)
1139 		return ret;
1140 
1141 	ret = target_check_reservation(cmd);
1142 	if (ret)
1143 		return ret;
1144 
1145 	ret = dev->transport->parse_cdb(cmd);
1146 	if (ret)
1147 		return ret;
1148 
1149 	ret = transport_check_alloc_task_attr(cmd);
1150 	if (ret)
1151 		return ret;
1152 
1153 	spin_lock_irqsave(&cmd->t_state_lock, flags);
1154 	cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1155 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1156 
1157 	spin_lock(&cmd->se_lun->lun_sep_lock);
1158 	if (cmd->se_lun->lun_sep)
1159 		cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1160 	spin_unlock(&cmd->se_lun->lun_sep_lock);
1161 	return 0;
1162 }
1163 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1164 
1165 /*
1166  * Used by fabric module frontends to queue tasks directly.
1167  * Many only be used from process context only
1168  */
1169 int transport_handle_cdb_direct(
1170 	struct se_cmd *cmd)
1171 {
1172 	sense_reason_t ret;
1173 
1174 	if (!cmd->se_lun) {
1175 		dump_stack();
1176 		pr_err("cmd->se_lun is NULL\n");
1177 		return -EINVAL;
1178 	}
1179 	if (in_interrupt()) {
1180 		dump_stack();
1181 		pr_err("transport_generic_handle_cdb cannot be called"
1182 				" from interrupt context\n");
1183 		return -EINVAL;
1184 	}
1185 	/*
1186 	 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1187 	 * outstanding descriptors are handled correctly during shutdown via
1188 	 * transport_wait_for_tasks()
1189 	 *
1190 	 * Also, we don't take cmd->t_state_lock here as we only expect
1191 	 * this to be called for initial descriptor submission.
1192 	 */
1193 	cmd->t_state = TRANSPORT_NEW_CMD;
1194 	cmd->transport_state |= CMD_T_ACTIVE;
1195 
1196 	/*
1197 	 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1198 	 * so follow TRANSPORT_NEW_CMD processing thread context usage
1199 	 * and call transport_generic_request_failure() if necessary..
1200 	 */
1201 	ret = transport_generic_new_cmd(cmd);
1202 	if (ret)
1203 		transport_generic_request_failure(cmd, ret);
1204 	return 0;
1205 }
1206 EXPORT_SYMBOL(transport_handle_cdb_direct);
1207 
1208 static sense_reason_t
1209 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1210 		u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1211 {
1212 	if (!sgl || !sgl_count)
1213 		return 0;
1214 
1215 	/*
1216 	 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1217 	 * scatterlists already have been set to follow what the fabric
1218 	 * passes for the original expected data transfer length.
1219 	 */
1220 	if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1221 		pr_warn("Rejecting SCSI DATA overflow for fabric using"
1222 			" SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1223 		return TCM_INVALID_CDB_FIELD;
1224 	}
1225 
1226 	cmd->t_data_sg = sgl;
1227 	cmd->t_data_nents = sgl_count;
1228 
1229 	if (sgl_bidi && sgl_bidi_count) {
1230 		cmd->t_bidi_data_sg = sgl_bidi;
1231 		cmd->t_bidi_data_nents = sgl_bidi_count;
1232 	}
1233 	cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1234 	return 0;
1235 }
1236 
1237 /*
1238  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1239  * 			 se_cmd + use pre-allocated SGL memory.
1240  *
1241  * @se_cmd: command descriptor to submit
1242  * @se_sess: associated se_sess for endpoint
1243  * @cdb: pointer to SCSI CDB
1244  * @sense: pointer to SCSI sense buffer
1245  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1246  * @data_length: fabric expected data transfer length
1247  * @task_addr: SAM task attribute
1248  * @data_dir: DMA data direction
1249  * @flags: flags for command submission from target_sc_flags_tables
1250  * @sgl: struct scatterlist memory for unidirectional mapping
1251  * @sgl_count: scatterlist count for unidirectional mapping
1252  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1253  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1254  *
1255  * Returns non zero to signal active I/O shutdown failure.  All other
1256  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1257  * but still return zero here.
1258  *
1259  * This may only be called from process context, and also currently
1260  * assumes internal allocation of fabric payload buffer by target-core.
1261  */
1262 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1263 		unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1264 		u32 data_length, int task_attr, int data_dir, int flags,
1265 		struct scatterlist *sgl, u32 sgl_count,
1266 		struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1267 {
1268 	struct se_portal_group *se_tpg;
1269 	sense_reason_t rc;
1270 	int ret;
1271 
1272 	se_tpg = se_sess->se_tpg;
1273 	BUG_ON(!se_tpg);
1274 	BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1275 	BUG_ON(in_interrupt());
1276 	/*
1277 	 * Initialize se_cmd for target operation.  From this point
1278 	 * exceptions are handled by sending exception status via
1279 	 * target_core_fabric_ops->queue_status() callback
1280 	 */
1281 	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1282 				data_length, data_dir, task_attr, sense);
1283 	if (flags & TARGET_SCF_UNKNOWN_SIZE)
1284 		se_cmd->unknown_data_length = 1;
1285 	/*
1286 	 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1287 	 * se_sess->sess_cmd_list.  A second kref_get here is necessary
1288 	 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1289 	 * kref_put() to happen during fabric packet acknowledgement.
1290 	 */
1291 	ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1292 	if (ret)
1293 		return ret;
1294 	/*
1295 	 * Signal bidirectional data payloads to target-core
1296 	 */
1297 	if (flags & TARGET_SCF_BIDI_OP)
1298 		se_cmd->se_cmd_flags |= SCF_BIDI;
1299 	/*
1300 	 * Locate se_lun pointer and attach it to struct se_cmd
1301 	 */
1302 	rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1303 	if (rc) {
1304 		transport_send_check_condition_and_sense(se_cmd, rc, 0);
1305 		target_put_sess_cmd(se_sess, se_cmd);
1306 		return 0;
1307 	}
1308 
1309 	rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1310 	if (rc != 0) {
1311 		transport_generic_request_failure(se_cmd, rc);
1312 		return 0;
1313 	}
1314 	/*
1315 	 * When a non zero sgl_count has been passed perform SGL passthrough
1316 	 * mapping for pre-allocated fabric memory instead of having target
1317 	 * core perform an internal SGL allocation..
1318 	 */
1319 	if (sgl_count != 0) {
1320 		BUG_ON(!sgl);
1321 
1322 		/*
1323 		 * A work-around for tcm_loop as some userspace code via
1324 		 * scsi-generic do not memset their associated read buffers,
1325 		 * so go ahead and do that here for type non-data CDBs.  Also
1326 		 * note that this is currently guaranteed to be a single SGL
1327 		 * for this case by target core in target_setup_cmd_from_cdb()
1328 		 * -> transport_generic_cmd_sequencer().
1329 		 */
1330 		if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1331 		     se_cmd->data_direction == DMA_FROM_DEVICE) {
1332 			unsigned char *buf = NULL;
1333 
1334 			if (sgl)
1335 				buf = kmap(sg_page(sgl)) + sgl->offset;
1336 
1337 			if (buf) {
1338 				memset(buf, 0, sgl->length);
1339 				kunmap(sg_page(sgl));
1340 			}
1341 		}
1342 
1343 		rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1344 				sgl_bidi, sgl_bidi_count);
1345 		if (rc != 0) {
1346 			transport_generic_request_failure(se_cmd, rc);
1347 			return 0;
1348 		}
1349 	}
1350 	/*
1351 	 * Check if we need to delay processing because of ALUA
1352 	 * Active/NonOptimized primary access state..
1353 	 */
1354 	core_alua_check_nonop_delay(se_cmd);
1355 
1356 	transport_handle_cdb_direct(se_cmd);
1357 	return 0;
1358 }
1359 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1360 
1361 /*
1362  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1363  *
1364  * @se_cmd: command descriptor to submit
1365  * @se_sess: associated se_sess for endpoint
1366  * @cdb: pointer to SCSI CDB
1367  * @sense: pointer to SCSI sense buffer
1368  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1369  * @data_length: fabric expected data transfer length
1370  * @task_addr: SAM task attribute
1371  * @data_dir: DMA data direction
1372  * @flags: flags for command submission from target_sc_flags_tables
1373  *
1374  * Returns non zero to signal active I/O shutdown failure.  All other
1375  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1376  * but still return zero here.
1377  *
1378  * This may only be called from process context, and also currently
1379  * assumes internal allocation of fabric payload buffer by target-core.
1380  *
1381  * It also assumes interal target core SGL memory allocation.
1382  */
1383 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1384 		unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1385 		u32 data_length, int task_attr, int data_dir, int flags)
1386 {
1387 	return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1388 			unpacked_lun, data_length, task_attr, data_dir,
1389 			flags, NULL, 0, NULL, 0);
1390 }
1391 EXPORT_SYMBOL(target_submit_cmd);
1392 
1393 static void target_complete_tmr_failure(struct work_struct *work)
1394 {
1395 	struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1396 
1397 	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1398 	se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1399 }
1400 
1401 /**
1402  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1403  *                     for TMR CDBs
1404  *
1405  * @se_cmd: command descriptor to submit
1406  * @se_sess: associated se_sess for endpoint
1407  * @sense: pointer to SCSI sense buffer
1408  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1409  * @fabric_context: fabric context for TMR req
1410  * @tm_type: Type of TM request
1411  * @gfp: gfp type for caller
1412  * @tag: referenced task tag for TMR_ABORT_TASK
1413  * @flags: submit cmd flags
1414  *
1415  * Callable from all contexts.
1416  **/
1417 
1418 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1419 		unsigned char *sense, u32 unpacked_lun,
1420 		void *fabric_tmr_ptr, unsigned char tm_type,
1421 		gfp_t gfp, unsigned int tag, int flags)
1422 {
1423 	struct se_portal_group *se_tpg;
1424 	int ret;
1425 
1426 	se_tpg = se_sess->se_tpg;
1427 	BUG_ON(!se_tpg);
1428 
1429 	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1430 			      0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1431 	/*
1432 	 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1433 	 * allocation failure.
1434 	 */
1435 	ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1436 	if (ret < 0)
1437 		return -ENOMEM;
1438 
1439 	if (tm_type == TMR_ABORT_TASK)
1440 		se_cmd->se_tmr_req->ref_task_tag = tag;
1441 
1442 	/* See target_submit_cmd for commentary */
1443 	ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1444 	if (ret) {
1445 		core_tmr_release_req(se_cmd->se_tmr_req);
1446 		return ret;
1447 	}
1448 
1449 	ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1450 	if (ret) {
1451 		/*
1452 		 * For callback during failure handling, push this work off
1453 		 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1454 		 */
1455 		INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1456 		schedule_work(&se_cmd->work);
1457 		return 0;
1458 	}
1459 	transport_generic_handle_tmr(se_cmd);
1460 	return 0;
1461 }
1462 EXPORT_SYMBOL(target_submit_tmr);
1463 
1464 /*
1465  * If the cmd is active, request it to be stopped and sleep until it
1466  * has completed.
1467  */
1468 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1469 {
1470 	bool was_active = false;
1471 
1472 	if (cmd->transport_state & CMD_T_BUSY) {
1473 		cmd->transport_state |= CMD_T_REQUEST_STOP;
1474 		spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1475 
1476 		pr_debug("cmd %p waiting to complete\n", cmd);
1477 		wait_for_completion(&cmd->task_stop_comp);
1478 		pr_debug("cmd %p stopped successfully\n", cmd);
1479 
1480 		spin_lock_irqsave(&cmd->t_state_lock, *flags);
1481 		cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1482 		cmd->transport_state &= ~CMD_T_BUSY;
1483 		was_active = true;
1484 	}
1485 
1486 	return was_active;
1487 }
1488 
1489 /*
1490  * Handle SAM-esque emulation for generic transport request failures.
1491  */
1492 void transport_generic_request_failure(struct se_cmd *cmd,
1493 		sense_reason_t sense_reason)
1494 {
1495 	int ret = 0;
1496 
1497 	pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1498 		" CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1499 		cmd->t_task_cdb[0]);
1500 	pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1501 		cmd->se_tfo->get_cmd_state(cmd),
1502 		cmd->t_state, sense_reason);
1503 	pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1504 		(cmd->transport_state & CMD_T_ACTIVE) != 0,
1505 		(cmd->transport_state & CMD_T_STOP) != 0,
1506 		(cmd->transport_state & CMD_T_SENT) != 0);
1507 
1508 	/*
1509 	 * For SAM Task Attribute emulation for failed struct se_cmd
1510 	 */
1511 	transport_complete_task_attr(cmd);
1512 
1513 	switch (sense_reason) {
1514 	case TCM_NON_EXISTENT_LUN:
1515 	case TCM_UNSUPPORTED_SCSI_OPCODE:
1516 	case TCM_INVALID_CDB_FIELD:
1517 	case TCM_INVALID_PARAMETER_LIST:
1518 	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1519 	case TCM_UNKNOWN_MODE_PAGE:
1520 	case TCM_WRITE_PROTECTED:
1521 	case TCM_ADDRESS_OUT_OF_RANGE:
1522 	case TCM_CHECK_CONDITION_ABORT_CMD:
1523 	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1524 	case TCM_CHECK_CONDITION_NOT_READY:
1525 		break;
1526 	case TCM_OUT_OF_RESOURCES:
1527 		sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1528 		break;
1529 	case TCM_RESERVATION_CONFLICT:
1530 		/*
1531 		 * No SENSE Data payload for this case, set SCSI Status
1532 		 * and queue the response to $FABRIC_MOD.
1533 		 *
1534 		 * Uses linux/include/scsi/scsi.h SAM status codes defs
1535 		 */
1536 		cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1537 		/*
1538 		 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1539 		 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1540 		 * CONFLICT STATUS.
1541 		 *
1542 		 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1543 		 */
1544 		if (cmd->se_sess &&
1545 		    cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1546 			core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1547 				cmd->orig_fe_lun, 0x2C,
1548 				ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1549 
1550 		ret = cmd->se_tfo->queue_status(cmd);
1551 		if (ret == -EAGAIN || ret == -ENOMEM)
1552 			goto queue_full;
1553 		goto check_stop;
1554 	default:
1555 		pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1556 			cmd->t_task_cdb[0], sense_reason);
1557 		sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1558 		break;
1559 	}
1560 
1561 	ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1562 	if (ret == -EAGAIN || ret == -ENOMEM)
1563 		goto queue_full;
1564 
1565 check_stop:
1566 	transport_lun_remove_cmd(cmd);
1567 	if (!transport_cmd_check_stop_to_fabric(cmd))
1568 		;
1569 	return;
1570 
1571 queue_full:
1572 	cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1573 	transport_handle_queue_full(cmd, cmd->se_dev);
1574 }
1575 EXPORT_SYMBOL(transport_generic_request_failure);
1576 
1577 static void __target_execute_cmd(struct se_cmd *cmd)
1578 {
1579 	sense_reason_t ret;
1580 
1581 	spin_lock_irq(&cmd->t_state_lock);
1582 	cmd->transport_state |= (CMD_T_BUSY|CMD_T_SENT);
1583 	spin_unlock_irq(&cmd->t_state_lock);
1584 
1585 	if (cmd->execute_cmd) {
1586 		ret = cmd->execute_cmd(cmd);
1587 		if (ret) {
1588 			spin_lock_irq(&cmd->t_state_lock);
1589 			cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1590 			spin_unlock_irq(&cmd->t_state_lock);
1591 
1592 			transport_generic_request_failure(cmd, ret);
1593 		}
1594 	}
1595 }
1596 
1597 static bool target_handle_task_attr(struct se_cmd *cmd)
1598 {
1599 	struct se_device *dev = cmd->se_dev;
1600 
1601 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1602 		return false;
1603 
1604 	/*
1605 	 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1606 	 * to allow the passed struct se_cmd list of tasks to the front of the list.
1607 	 */
1608 	switch (cmd->sam_task_attr) {
1609 	case MSG_HEAD_TAG:
1610 		pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1611 			 "se_ordered_id: %u\n",
1612 			 cmd->t_task_cdb[0], cmd->se_ordered_id);
1613 		return false;
1614 	case MSG_ORDERED_TAG:
1615 		atomic_inc(&dev->dev_ordered_sync);
1616 		smp_mb__after_atomic_inc();
1617 
1618 		pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1619 			 " se_ordered_id: %u\n",
1620 			 cmd->t_task_cdb[0], cmd->se_ordered_id);
1621 
1622 		/*
1623 		 * Execute an ORDERED command if no other older commands
1624 		 * exist that need to be completed first.
1625 		 */
1626 		if (!atomic_read(&dev->simple_cmds))
1627 			return false;
1628 		break;
1629 	default:
1630 		/*
1631 		 * For SIMPLE and UNTAGGED Task Attribute commands
1632 		 */
1633 		atomic_inc(&dev->simple_cmds);
1634 		smp_mb__after_atomic_inc();
1635 		break;
1636 	}
1637 
1638 	if (atomic_read(&dev->dev_ordered_sync) == 0)
1639 		return false;
1640 
1641 	spin_lock(&dev->delayed_cmd_lock);
1642 	list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1643 	spin_unlock(&dev->delayed_cmd_lock);
1644 
1645 	pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1646 		" delayed CMD list, se_ordered_id: %u\n",
1647 		cmd->t_task_cdb[0], cmd->sam_task_attr,
1648 		cmd->se_ordered_id);
1649 	return true;
1650 }
1651 
1652 void target_execute_cmd(struct se_cmd *cmd)
1653 {
1654 	/*
1655 	 * If the received CDB has aleady been aborted stop processing it here.
1656 	 */
1657 	if (transport_check_aborted_status(cmd, 1)) {
1658 		complete(&cmd->transport_lun_stop_comp);
1659 		return;
1660 	}
1661 
1662 	/*
1663 	 * Determine if IOCTL context caller in requesting the stopping of this
1664 	 * command for LUN shutdown purposes.
1665 	 */
1666 	spin_lock_irq(&cmd->t_state_lock);
1667 	if (cmd->transport_state & CMD_T_LUN_STOP) {
1668 		pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
1669 			__func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
1670 
1671 		cmd->transport_state &= ~CMD_T_ACTIVE;
1672 		spin_unlock_irq(&cmd->t_state_lock);
1673 		complete(&cmd->transport_lun_stop_comp);
1674 		return;
1675 	}
1676 	/*
1677 	 * Determine if frontend context caller is requesting the stopping of
1678 	 * this command for frontend exceptions.
1679 	 */
1680 	if (cmd->transport_state & CMD_T_STOP) {
1681 		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1682 			__func__, __LINE__,
1683 			cmd->se_tfo->get_task_tag(cmd));
1684 
1685 		spin_unlock_irq(&cmd->t_state_lock);
1686 		complete(&cmd->t_transport_stop_comp);
1687 		return;
1688 	}
1689 
1690 	cmd->t_state = TRANSPORT_PROCESSING;
1691 	spin_unlock_irq(&cmd->t_state_lock);
1692 
1693 	if (!target_handle_task_attr(cmd))
1694 		__target_execute_cmd(cmd);
1695 }
1696 EXPORT_SYMBOL(target_execute_cmd);
1697 
1698 /*
1699  * Process all commands up to the last received ORDERED task attribute which
1700  * requires another blocking boundary
1701  */
1702 static void target_restart_delayed_cmds(struct se_device *dev)
1703 {
1704 	for (;;) {
1705 		struct se_cmd *cmd;
1706 
1707 		spin_lock(&dev->delayed_cmd_lock);
1708 		if (list_empty(&dev->delayed_cmd_list)) {
1709 			spin_unlock(&dev->delayed_cmd_lock);
1710 			break;
1711 		}
1712 
1713 		cmd = list_entry(dev->delayed_cmd_list.next,
1714 				 struct se_cmd, se_delayed_node);
1715 		list_del(&cmd->se_delayed_node);
1716 		spin_unlock(&dev->delayed_cmd_lock);
1717 
1718 		__target_execute_cmd(cmd);
1719 
1720 		if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1721 			break;
1722 	}
1723 }
1724 
1725 /*
1726  * Called from I/O completion to determine which dormant/delayed
1727  * and ordered cmds need to have their tasks added to the execution queue.
1728  */
1729 static void transport_complete_task_attr(struct se_cmd *cmd)
1730 {
1731 	struct se_device *dev = cmd->se_dev;
1732 
1733 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1734 		return;
1735 
1736 	if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1737 		atomic_dec(&dev->simple_cmds);
1738 		smp_mb__after_atomic_dec();
1739 		dev->dev_cur_ordered_id++;
1740 		pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1741 			" SIMPLE: %u\n", dev->dev_cur_ordered_id,
1742 			cmd->se_ordered_id);
1743 	} else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1744 		dev->dev_cur_ordered_id++;
1745 		pr_debug("Incremented dev_cur_ordered_id: %u for"
1746 			" HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1747 			cmd->se_ordered_id);
1748 	} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1749 		atomic_dec(&dev->dev_ordered_sync);
1750 		smp_mb__after_atomic_dec();
1751 
1752 		dev->dev_cur_ordered_id++;
1753 		pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1754 			" %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1755 	}
1756 
1757 	target_restart_delayed_cmds(dev);
1758 }
1759 
1760 static void transport_complete_qf(struct se_cmd *cmd)
1761 {
1762 	int ret = 0;
1763 
1764 	transport_complete_task_attr(cmd);
1765 
1766 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1767 		ret = cmd->se_tfo->queue_status(cmd);
1768 		if (ret)
1769 			goto out;
1770 	}
1771 
1772 	switch (cmd->data_direction) {
1773 	case DMA_FROM_DEVICE:
1774 		ret = cmd->se_tfo->queue_data_in(cmd);
1775 		break;
1776 	case DMA_TO_DEVICE:
1777 		if (cmd->t_bidi_data_sg) {
1778 			ret = cmd->se_tfo->queue_data_in(cmd);
1779 			if (ret < 0)
1780 				break;
1781 		}
1782 		/* Fall through for DMA_TO_DEVICE */
1783 	case DMA_NONE:
1784 		ret = cmd->se_tfo->queue_status(cmd);
1785 		break;
1786 	default:
1787 		break;
1788 	}
1789 
1790 out:
1791 	if (ret < 0) {
1792 		transport_handle_queue_full(cmd, cmd->se_dev);
1793 		return;
1794 	}
1795 	transport_lun_remove_cmd(cmd);
1796 	transport_cmd_check_stop_to_fabric(cmd);
1797 }
1798 
1799 static void transport_handle_queue_full(
1800 	struct se_cmd *cmd,
1801 	struct se_device *dev)
1802 {
1803 	spin_lock_irq(&dev->qf_cmd_lock);
1804 	list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1805 	atomic_inc(&dev->dev_qf_count);
1806 	smp_mb__after_atomic_inc();
1807 	spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1808 
1809 	schedule_work(&cmd->se_dev->qf_work_queue);
1810 }
1811 
1812 static void target_complete_ok_work(struct work_struct *work)
1813 {
1814 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1815 	int ret;
1816 
1817 	/*
1818 	 * Check if we need to move delayed/dormant tasks from cmds on the
1819 	 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1820 	 * Attribute.
1821 	 */
1822 	transport_complete_task_attr(cmd);
1823 
1824 	/*
1825 	 * Check to schedule QUEUE_FULL work, or execute an existing
1826 	 * cmd->transport_qf_callback()
1827 	 */
1828 	if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1829 		schedule_work(&cmd->se_dev->qf_work_queue);
1830 
1831 	/*
1832 	 * Check if we need to send a sense buffer from
1833 	 * the struct se_cmd in question.
1834 	 */
1835 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1836 		WARN_ON(!cmd->scsi_status);
1837 		ret = transport_send_check_condition_and_sense(
1838 					cmd, 0, 1);
1839 		if (ret == -EAGAIN || ret == -ENOMEM)
1840 			goto queue_full;
1841 
1842 		transport_lun_remove_cmd(cmd);
1843 		transport_cmd_check_stop_to_fabric(cmd);
1844 		return;
1845 	}
1846 	/*
1847 	 * Check for a callback, used by amongst other things
1848 	 * XDWRITE_READ_10 emulation.
1849 	 */
1850 	if (cmd->transport_complete_callback)
1851 		cmd->transport_complete_callback(cmd);
1852 
1853 	switch (cmd->data_direction) {
1854 	case DMA_FROM_DEVICE:
1855 		spin_lock(&cmd->se_lun->lun_sep_lock);
1856 		if (cmd->se_lun->lun_sep) {
1857 			cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1858 					cmd->data_length;
1859 		}
1860 		spin_unlock(&cmd->se_lun->lun_sep_lock);
1861 
1862 		ret = cmd->se_tfo->queue_data_in(cmd);
1863 		if (ret == -EAGAIN || ret == -ENOMEM)
1864 			goto queue_full;
1865 		break;
1866 	case DMA_TO_DEVICE:
1867 		spin_lock(&cmd->se_lun->lun_sep_lock);
1868 		if (cmd->se_lun->lun_sep) {
1869 			cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
1870 				cmd->data_length;
1871 		}
1872 		spin_unlock(&cmd->se_lun->lun_sep_lock);
1873 		/*
1874 		 * Check if we need to send READ payload for BIDI-COMMAND
1875 		 */
1876 		if (cmd->t_bidi_data_sg) {
1877 			spin_lock(&cmd->se_lun->lun_sep_lock);
1878 			if (cmd->se_lun->lun_sep) {
1879 				cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1880 					cmd->data_length;
1881 			}
1882 			spin_unlock(&cmd->se_lun->lun_sep_lock);
1883 			ret = cmd->se_tfo->queue_data_in(cmd);
1884 			if (ret == -EAGAIN || ret == -ENOMEM)
1885 				goto queue_full;
1886 			break;
1887 		}
1888 		/* Fall through for DMA_TO_DEVICE */
1889 	case DMA_NONE:
1890 		ret = cmd->se_tfo->queue_status(cmd);
1891 		if (ret == -EAGAIN || ret == -ENOMEM)
1892 			goto queue_full;
1893 		break;
1894 	default:
1895 		break;
1896 	}
1897 
1898 	transport_lun_remove_cmd(cmd);
1899 	transport_cmd_check_stop_to_fabric(cmd);
1900 	return;
1901 
1902 queue_full:
1903 	pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
1904 		" data_direction: %d\n", cmd, cmd->data_direction);
1905 	cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1906 	transport_handle_queue_full(cmd, cmd->se_dev);
1907 }
1908 
1909 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
1910 {
1911 	struct scatterlist *sg;
1912 	int count;
1913 
1914 	for_each_sg(sgl, sg, nents, count)
1915 		__free_page(sg_page(sg));
1916 
1917 	kfree(sgl);
1918 }
1919 
1920 static inline void transport_free_pages(struct se_cmd *cmd)
1921 {
1922 	if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
1923 		return;
1924 
1925 	transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
1926 	cmd->t_data_sg = NULL;
1927 	cmd->t_data_nents = 0;
1928 
1929 	transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
1930 	cmd->t_bidi_data_sg = NULL;
1931 	cmd->t_bidi_data_nents = 0;
1932 }
1933 
1934 /**
1935  * transport_release_cmd - free a command
1936  * @cmd:       command to free
1937  *
1938  * This routine unconditionally frees a command, and reference counting
1939  * or list removal must be done in the caller.
1940  */
1941 static void transport_release_cmd(struct se_cmd *cmd)
1942 {
1943 	BUG_ON(!cmd->se_tfo);
1944 
1945 	if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1946 		core_tmr_release_req(cmd->se_tmr_req);
1947 	if (cmd->t_task_cdb != cmd->__t_task_cdb)
1948 		kfree(cmd->t_task_cdb);
1949 	/*
1950 	 * If this cmd has been setup with target_get_sess_cmd(), drop
1951 	 * the kref and call ->release_cmd() in kref callback.
1952 	 */
1953 	 if (cmd->check_release != 0) {
1954 		target_put_sess_cmd(cmd->se_sess, cmd);
1955 		return;
1956 	}
1957 	cmd->se_tfo->release_cmd(cmd);
1958 }
1959 
1960 /**
1961  * transport_put_cmd - release a reference to a command
1962  * @cmd:       command to release
1963  *
1964  * This routine releases our reference to the command and frees it if possible.
1965  */
1966 static void transport_put_cmd(struct se_cmd *cmd)
1967 {
1968 	unsigned long flags;
1969 
1970 	spin_lock_irqsave(&cmd->t_state_lock, flags);
1971 	if (atomic_read(&cmd->t_fe_count) &&
1972 	    !atomic_dec_and_test(&cmd->t_fe_count)) {
1973 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1974 		return;
1975 	}
1976 
1977 	if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
1978 		cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
1979 		target_remove_from_state_list(cmd);
1980 	}
1981 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1982 
1983 	transport_free_pages(cmd);
1984 	transport_release_cmd(cmd);
1985 	return;
1986 }
1987 
1988 void *transport_kmap_data_sg(struct se_cmd *cmd)
1989 {
1990 	struct scatterlist *sg = cmd->t_data_sg;
1991 	struct page **pages;
1992 	int i;
1993 
1994 	/*
1995 	 * We need to take into account a possible offset here for fabrics like
1996 	 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
1997 	 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
1998 	 */
1999 	if (!cmd->t_data_nents)
2000 		return NULL;
2001 
2002 	BUG_ON(!sg);
2003 	if (cmd->t_data_nents == 1)
2004 		return kmap(sg_page(sg)) + sg->offset;
2005 
2006 	/* >1 page. use vmap */
2007 	pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2008 	if (!pages)
2009 		return NULL;
2010 
2011 	/* convert sg[] to pages[] */
2012 	for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2013 		pages[i] = sg_page(sg);
2014 	}
2015 
2016 	cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2017 	kfree(pages);
2018 	if (!cmd->t_data_vmap)
2019 		return NULL;
2020 
2021 	return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2022 }
2023 EXPORT_SYMBOL(transport_kmap_data_sg);
2024 
2025 void transport_kunmap_data_sg(struct se_cmd *cmd)
2026 {
2027 	if (!cmd->t_data_nents) {
2028 		return;
2029 	} else if (cmd->t_data_nents == 1) {
2030 		kunmap(sg_page(cmd->t_data_sg));
2031 		return;
2032 	}
2033 
2034 	vunmap(cmd->t_data_vmap);
2035 	cmd->t_data_vmap = NULL;
2036 }
2037 EXPORT_SYMBOL(transport_kunmap_data_sg);
2038 
2039 static int
2040 transport_generic_get_mem(struct se_cmd *cmd)
2041 {
2042 	u32 length = cmd->data_length;
2043 	unsigned int nents;
2044 	struct page *page;
2045 	gfp_t zero_flag;
2046 	int i = 0;
2047 
2048 	nents = DIV_ROUND_UP(length, PAGE_SIZE);
2049 	cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
2050 	if (!cmd->t_data_sg)
2051 		return -ENOMEM;
2052 
2053 	cmd->t_data_nents = nents;
2054 	sg_init_table(cmd->t_data_sg, nents);
2055 
2056 	zero_flag = cmd->se_cmd_flags & SCF_SCSI_DATA_CDB ? 0 : __GFP_ZERO;
2057 
2058 	while (length) {
2059 		u32 page_len = min_t(u32, length, PAGE_SIZE);
2060 		page = alloc_page(GFP_KERNEL | zero_flag);
2061 		if (!page)
2062 			goto out;
2063 
2064 		sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
2065 		length -= page_len;
2066 		i++;
2067 	}
2068 	return 0;
2069 
2070 out:
2071 	while (i > 0) {
2072 		i--;
2073 		__free_page(sg_page(&cmd->t_data_sg[i]));
2074 	}
2075 	kfree(cmd->t_data_sg);
2076 	cmd->t_data_sg = NULL;
2077 	return -ENOMEM;
2078 }
2079 
2080 /*
2081  * Allocate any required resources to execute the command.  For writes we
2082  * might not have the payload yet, so notify the fabric via a call to
2083  * ->write_pending instead. Otherwise place it on the execution queue.
2084  */
2085 sense_reason_t
2086 transport_generic_new_cmd(struct se_cmd *cmd)
2087 {
2088 	int ret = 0;
2089 
2090 	/*
2091 	 * Determine is the TCM fabric module has already allocated physical
2092 	 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2093 	 * beforehand.
2094 	 */
2095 	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2096 	    cmd->data_length) {
2097 		ret = transport_generic_get_mem(cmd);
2098 		if (ret < 0)
2099 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2100 	}
2101 
2102 	atomic_inc(&cmd->t_fe_count);
2103 
2104 	/*
2105 	 * If this command is not a write we can execute it right here,
2106 	 * for write buffers we need to notify the fabric driver first
2107 	 * and let it call back once the write buffers are ready.
2108 	 */
2109 	target_add_to_state_list(cmd);
2110 	if (cmd->data_direction != DMA_TO_DEVICE) {
2111 		target_execute_cmd(cmd);
2112 		return 0;
2113 	}
2114 
2115 	spin_lock_irq(&cmd->t_state_lock);
2116 	cmd->t_state = TRANSPORT_WRITE_PENDING;
2117 	spin_unlock_irq(&cmd->t_state_lock);
2118 
2119 	transport_cmd_check_stop(cmd, false);
2120 
2121 	ret = cmd->se_tfo->write_pending(cmd);
2122 	if (ret == -EAGAIN || ret == -ENOMEM)
2123 		goto queue_full;
2124 
2125 	/* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2126 	WARN_ON(ret);
2127 
2128 	return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2129 
2130 queue_full:
2131 	pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2132 	cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2133 	transport_handle_queue_full(cmd, cmd->se_dev);
2134 	return 0;
2135 }
2136 EXPORT_SYMBOL(transport_generic_new_cmd);
2137 
2138 static void transport_write_pending_qf(struct se_cmd *cmd)
2139 {
2140 	int ret;
2141 
2142 	ret = cmd->se_tfo->write_pending(cmd);
2143 	if (ret == -EAGAIN || ret == -ENOMEM) {
2144 		pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2145 			 cmd);
2146 		transport_handle_queue_full(cmd, cmd->se_dev);
2147 	}
2148 }
2149 
2150 void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2151 {
2152 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2153 		if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2154 			 transport_wait_for_tasks(cmd);
2155 
2156 		transport_release_cmd(cmd);
2157 	} else {
2158 		if (wait_for_tasks)
2159 			transport_wait_for_tasks(cmd);
2160 
2161 		core_dec_lacl_count(cmd->se_sess->se_node_acl, cmd);
2162 
2163 		if (cmd->se_lun)
2164 			transport_lun_remove_cmd(cmd);
2165 
2166 		transport_put_cmd(cmd);
2167 	}
2168 }
2169 EXPORT_SYMBOL(transport_generic_free_cmd);
2170 
2171 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2172  * @se_sess:	session to reference
2173  * @se_cmd:	command descriptor to add
2174  * @ack_kref:	Signal that fabric will perform an ack target_put_sess_cmd()
2175  */
2176 static int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2177 			       bool ack_kref)
2178 {
2179 	unsigned long flags;
2180 	int ret = 0;
2181 
2182 	kref_init(&se_cmd->cmd_kref);
2183 	/*
2184 	 * Add a second kref if the fabric caller is expecting to handle
2185 	 * fabric acknowledgement that requires two target_put_sess_cmd()
2186 	 * invocations before se_cmd descriptor release.
2187 	 */
2188 	if (ack_kref == true) {
2189 		kref_get(&se_cmd->cmd_kref);
2190 		se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2191 	}
2192 
2193 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2194 	if (se_sess->sess_tearing_down) {
2195 		ret = -ESHUTDOWN;
2196 		goto out;
2197 	}
2198 	list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2199 	se_cmd->check_release = 1;
2200 
2201 out:
2202 	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2203 	return ret;
2204 }
2205 
2206 static void target_release_cmd_kref(struct kref *kref)
2207 {
2208 	struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2209 	struct se_session *se_sess = se_cmd->se_sess;
2210 	unsigned long flags;
2211 
2212 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2213 	if (list_empty(&se_cmd->se_cmd_list)) {
2214 		spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2215 		se_cmd->se_tfo->release_cmd(se_cmd);
2216 		return;
2217 	}
2218 	if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2219 		spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2220 		complete(&se_cmd->cmd_wait_comp);
2221 		return;
2222 	}
2223 	list_del(&se_cmd->se_cmd_list);
2224 	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2225 
2226 	se_cmd->se_tfo->release_cmd(se_cmd);
2227 }
2228 
2229 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2230  * @se_sess:	session to reference
2231  * @se_cmd:	command descriptor to drop
2232  */
2233 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2234 {
2235 	return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2236 }
2237 EXPORT_SYMBOL(target_put_sess_cmd);
2238 
2239 /* target_sess_cmd_list_set_waiting - Flag all commands in
2240  *         sess_cmd_list to complete cmd_wait_comp.  Set
2241  *         sess_tearing_down so no more commands are queued.
2242  * @se_sess:	session to flag
2243  */
2244 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2245 {
2246 	struct se_cmd *se_cmd;
2247 	unsigned long flags;
2248 
2249 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2250 
2251 	WARN_ON(se_sess->sess_tearing_down);
2252 	se_sess->sess_tearing_down = 1;
2253 
2254 	list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list)
2255 		se_cmd->cmd_wait_set = 1;
2256 
2257 	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2258 }
2259 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2260 
2261 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2262  * @se_sess:    session to wait for active I/O
2263  * @wait_for_tasks:	Make extra transport_wait_for_tasks call
2264  */
2265 void target_wait_for_sess_cmds(
2266 	struct se_session *se_sess,
2267 	int wait_for_tasks)
2268 {
2269 	struct se_cmd *se_cmd, *tmp_cmd;
2270 	bool rc = false;
2271 
2272 	list_for_each_entry_safe(se_cmd, tmp_cmd,
2273 				&se_sess->sess_cmd_list, se_cmd_list) {
2274 		list_del(&se_cmd->se_cmd_list);
2275 
2276 		pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2277 			" %d\n", se_cmd, se_cmd->t_state,
2278 			se_cmd->se_tfo->get_cmd_state(se_cmd));
2279 
2280 		if (wait_for_tasks) {
2281 			pr_debug("Calling transport_wait_for_tasks se_cmd: %p t_state: %d,"
2282 				" fabric state: %d\n", se_cmd, se_cmd->t_state,
2283 				se_cmd->se_tfo->get_cmd_state(se_cmd));
2284 
2285 			rc = transport_wait_for_tasks(se_cmd);
2286 
2287 			pr_debug("After transport_wait_for_tasks se_cmd: %p t_state: %d,"
2288 				" fabric state: %d\n", se_cmd, se_cmd->t_state,
2289 				se_cmd->se_tfo->get_cmd_state(se_cmd));
2290 		}
2291 
2292 		if (!rc) {
2293 			wait_for_completion(&se_cmd->cmd_wait_comp);
2294 			pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2295 				" fabric state: %d\n", se_cmd, se_cmd->t_state,
2296 				se_cmd->se_tfo->get_cmd_state(se_cmd));
2297 		}
2298 
2299 		se_cmd->se_tfo->release_cmd(se_cmd);
2300 	}
2301 }
2302 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2303 
2304 /*	transport_lun_wait_for_tasks():
2305  *
2306  *	Called from ConfigFS context to stop the passed struct se_cmd to allow
2307  *	an struct se_lun to be successfully shutdown.
2308  */
2309 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
2310 {
2311 	unsigned long flags;
2312 	int ret = 0;
2313 
2314 	/*
2315 	 * If the frontend has already requested this struct se_cmd to
2316 	 * be stopped, we can safely ignore this struct se_cmd.
2317 	 */
2318 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2319 	if (cmd->transport_state & CMD_T_STOP) {
2320 		cmd->transport_state &= ~CMD_T_LUN_STOP;
2321 
2322 		pr_debug("ConfigFS ITT[0x%08x] - CMD_T_STOP, skipping\n",
2323 			 cmd->se_tfo->get_task_tag(cmd));
2324 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2325 		transport_cmd_check_stop(cmd, false);
2326 		return -EPERM;
2327 	}
2328 	cmd->transport_state |= CMD_T_LUN_FE_STOP;
2329 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2330 
2331 	// XXX: audit task_flags checks.
2332 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2333 	if ((cmd->transport_state & CMD_T_BUSY) &&
2334 	    (cmd->transport_state & CMD_T_SENT)) {
2335 		if (!target_stop_cmd(cmd, &flags))
2336 			ret++;
2337 	}
2338 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2339 
2340 	pr_debug("ConfigFS: cmd: %p stop tasks ret:"
2341 			" %d\n", cmd, ret);
2342 	if (!ret) {
2343 		pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
2344 				cmd->se_tfo->get_task_tag(cmd));
2345 		wait_for_completion(&cmd->transport_lun_stop_comp);
2346 		pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
2347 				cmd->se_tfo->get_task_tag(cmd));
2348 	}
2349 
2350 	return 0;
2351 }
2352 
2353 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
2354 {
2355 	struct se_cmd *cmd = NULL;
2356 	unsigned long lun_flags, cmd_flags;
2357 	/*
2358 	 * Do exception processing and return CHECK_CONDITION status to the
2359 	 * Initiator Port.
2360 	 */
2361 	spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2362 	while (!list_empty(&lun->lun_cmd_list)) {
2363 		cmd = list_first_entry(&lun->lun_cmd_list,
2364 		       struct se_cmd, se_lun_node);
2365 		list_del_init(&cmd->se_lun_node);
2366 
2367 		spin_lock(&cmd->t_state_lock);
2368 		pr_debug("SE_LUN[%d] - Setting cmd->transport"
2369 			"_lun_stop for  ITT: 0x%08x\n",
2370 			cmd->se_lun->unpacked_lun,
2371 			cmd->se_tfo->get_task_tag(cmd));
2372 		cmd->transport_state |= CMD_T_LUN_STOP;
2373 		spin_unlock(&cmd->t_state_lock);
2374 
2375 		spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2376 
2377 		if (!cmd->se_lun) {
2378 			pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
2379 				cmd->se_tfo->get_task_tag(cmd),
2380 				cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2381 			BUG();
2382 		}
2383 		/*
2384 		 * If the Storage engine still owns the iscsi_cmd_t, determine
2385 		 * and/or stop its context.
2386 		 */
2387 		pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
2388 			"_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
2389 			cmd->se_tfo->get_task_tag(cmd));
2390 
2391 		if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
2392 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2393 			continue;
2394 		}
2395 
2396 		pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
2397 			"_wait_for_tasks(): SUCCESS\n",
2398 			cmd->se_lun->unpacked_lun,
2399 			cmd->se_tfo->get_task_tag(cmd));
2400 
2401 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2402 		if (!(cmd->transport_state & CMD_T_DEV_ACTIVE)) {
2403 			spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2404 			goto check_cond;
2405 		}
2406 		cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
2407 		target_remove_from_state_list(cmd);
2408 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2409 
2410 		/*
2411 		 * The Storage engine stopped this struct se_cmd before it was
2412 		 * send to the fabric frontend for delivery back to the
2413 		 * Initiator Node.  Return this SCSI CDB back with an
2414 		 * CHECK_CONDITION status.
2415 		 */
2416 check_cond:
2417 		transport_send_check_condition_and_sense(cmd,
2418 				TCM_NON_EXISTENT_LUN, 0);
2419 		/*
2420 		 *  If the fabric frontend is waiting for this iscsi_cmd_t to
2421 		 * be released, notify the waiting thread now that LU has
2422 		 * finished accessing it.
2423 		 */
2424 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2425 		if (cmd->transport_state & CMD_T_LUN_FE_STOP) {
2426 			pr_debug("SE_LUN[%d] - Detected FE stop for"
2427 				" struct se_cmd: %p ITT: 0x%08x\n",
2428 				lun->unpacked_lun,
2429 				cmd, cmd->se_tfo->get_task_tag(cmd));
2430 
2431 			spin_unlock_irqrestore(&cmd->t_state_lock,
2432 					cmd_flags);
2433 			transport_cmd_check_stop(cmd, false);
2434 			complete(&cmd->transport_lun_fe_stop_comp);
2435 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2436 			continue;
2437 		}
2438 		pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
2439 			lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
2440 
2441 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2442 		spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2443 	}
2444 	spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2445 }
2446 
2447 static int transport_clear_lun_thread(void *p)
2448 {
2449 	struct se_lun *lun = p;
2450 
2451 	__transport_clear_lun_from_sessions(lun);
2452 	complete(&lun->lun_shutdown_comp);
2453 
2454 	return 0;
2455 }
2456 
2457 int transport_clear_lun_from_sessions(struct se_lun *lun)
2458 {
2459 	struct task_struct *kt;
2460 
2461 	kt = kthread_run(transport_clear_lun_thread, lun,
2462 			"tcm_cl_%u", lun->unpacked_lun);
2463 	if (IS_ERR(kt)) {
2464 		pr_err("Unable to start clear_lun thread\n");
2465 		return PTR_ERR(kt);
2466 	}
2467 	wait_for_completion(&lun->lun_shutdown_comp);
2468 
2469 	return 0;
2470 }
2471 
2472 /**
2473  * transport_wait_for_tasks - wait for completion to occur
2474  * @cmd:	command to wait
2475  *
2476  * Called from frontend fabric context to wait for storage engine
2477  * to pause and/or release frontend generated struct se_cmd.
2478  */
2479 bool transport_wait_for_tasks(struct se_cmd *cmd)
2480 {
2481 	unsigned long flags;
2482 
2483 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2484 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2485 	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2486 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2487 		return false;
2488 	}
2489 
2490 	if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2491 	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2492 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2493 		return false;
2494 	}
2495 	/*
2496 	 * If we are already stopped due to an external event (ie: LUN shutdown)
2497 	 * sleep until the connection can have the passed struct se_cmd back.
2498 	 * The cmd->transport_lun_stopped_sem will be upped by
2499 	 * transport_clear_lun_from_sessions() once the ConfigFS context caller
2500 	 * has completed its operation on the struct se_cmd.
2501 	 */
2502 	if (cmd->transport_state & CMD_T_LUN_STOP) {
2503 		pr_debug("wait_for_tasks: Stopping"
2504 			" wait_for_completion(&cmd->t_tasktransport_lun_fe"
2505 			"_stop_comp); for ITT: 0x%08x\n",
2506 			cmd->se_tfo->get_task_tag(cmd));
2507 		/*
2508 		 * There is a special case for WRITES where a FE exception +
2509 		 * LUN shutdown means ConfigFS context is still sleeping on
2510 		 * transport_lun_stop_comp in transport_lun_wait_for_tasks().
2511 		 * We go ahead and up transport_lun_stop_comp just to be sure
2512 		 * here.
2513 		 */
2514 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2515 		complete(&cmd->transport_lun_stop_comp);
2516 		wait_for_completion(&cmd->transport_lun_fe_stop_comp);
2517 		spin_lock_irqsave(&cmd->t_state_lock, flags);
2518 
2519 		target_remove_from_state_list(cmd);
2520 		/*
2521 		 * At this point, the frontend who was the originator of this
2522 		 * struct se_cmd, now owns the structure and can be released through
2523 		 * normal means below.
2524 		 */
2525 		pr_debug("wait_for_tasks: Stopped"
2526 			" wait_for_completion(&cmd->t_tasktransport_lun_fe_"
2527 			"stop_comp); for ITT: 0x%08x\n",
2528 			cmd->se_tfo->get_task_tag(cmd));
2529 
2530 		cmd->transport_state &= ~CMD_T_LUN_STOP;
2531 	}
2532 
2533 	if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2534 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2535 		return false;
2536 	}
2537 
2538 	cmd->transport_state |= CMD_T_STOP;
2539 
2540 	pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2541 		" i_state: %d, t_state: %d, CMD_T_STOP\n",
2542 		cmd, cmd->se_tfo->get_task_tag(cmd),
2543 		cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2544 
2545 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2546 
2547 	wait_for_completion(&cmd->t_transport_stop_comp);
2548 
2549 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2550 	cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2551 
2552 	pr_debug("wait_for_tasks: Stopped wait_for_completion("
2553 		"&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2554 		cmd->se_tfo->get_task_tag(cmd));
2555 
2556 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2557 
2558 	return true;
2559 }
2560 EXPORT_SYMBOL(transport_wait_for_tasks);
2561 
2562 static int transport_get_sense_codes(
2563 	struct se_cmd *cmd,
2564 	u8 *asc,
2565 	u8 *ascq)
2566 {
2567 	*asc = cmd->scsi_asc;
2568 	*ascq = cmd->scsi_ascq;
2569 
2570 	return 0;
2571 }
2572 
2573 int
2574 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2575 		sense_reason_t reason, int from_transport)
2576 {
2577 	unsigned char *buffer = cmd->sense_buffer;
2578 	unsigned long flags;
2579 	u8 asc = 0, ascq = 0;
2580 
2581 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2582 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2583 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2584 		return 0;
2585 	}
2586 	cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2587 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2588 
2589 	if (!reason && from_transport)
2590 		goto after_reason;
2591 
2592 	if (!from_transport)
2593 		cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2594 
2595 	/*
2596 	 * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2597 	 * SENSE KEY values from include/scsi/scsi.h
2598 	 */
2599 	switch (reason) {
2600 	case TCM_NON_EXISTENT_LUN:
2601 		/* CURRENT ERROR */
2602 		buffer[0] = 0x70;
2603 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2604 		/* ILLEGAL REQUEST */
2605 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2606 		/* LOGICAL UNIT NOT SUPPORTED */
2607 		buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2608 		break;
2609 	case TCM_UNSUPPORTED_SCSI_OPCODE:
2610 	case TCM_SECTOR_COUNT_TOO_MANY:
2611 		/* CURRENT ERROR */
2612 		buffer[0] = 0x70;
2613 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2614 		/* ILLEGAL REQUEST */
2615 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2616 		/* INVALID COMMAND OPERATION CODE */
2617 		buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2618 		break;
2619 	case TCM_UNKNOWN_MODE_PAGE:
2620 		/* CURRENT ERROR */
2621 		buffer[0] = 0x70;
2622 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2623 		/* ILLEGAL REQUEST */
2624 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2625 		/* INVALID FIELD IN CDB */
2626 		buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2627 		break;
2628 	case TCM_CHECK_CONDITION_ABORT_CMD:
2629 		/* CURRENT ERROR */
2630 		buffer[0] = 0x70;
2631 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2632 		/* ABORTED COMMAND */
2633 		buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2634 		/* BUS DEVICE RESET FUNCTION OCCURRED */
2635 		buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2636 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2637 		break;
2638 	case TCM_INCORRECT_AMOUNT_OF_DATA:
2639 		/* CURRENT ERROR */
2640 		buffer[0] = 0x70;
2641 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2642 		/* ABORTED COMMAND */
2643 		buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2644 		/* WRITE ERROR */
2645 		buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2646 		/* NOT ENOUGH UNSOLICITED DATA */
2647 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2648 		break;
2649 	case TCM_INVALID_CDB_FIELD:
2650 		/* CURRENT ERROR */
2651 		buffer[0] = 0x70;
2652 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2653 		/* ILLEGAL REQUEST */
2654 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2655 		/* INVALID FIELD IN CDB */
2656 		buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2657 		break;
2658 	case TCM_INVALID_PARAMETER_LIST:
2659 		/* CURRENT ERROR */
2660 		buffer[0] = 0x70;
2661 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2662 		/* ILLEGAL REQUEST */
2663 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2664 		/* INVALID FIELD IN PARAMETER LIST */
2665 		buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2666 		break;
2667 	case TCM_UNEXPECTED_UNSOLICITED_DATA:
2668 		/* CURRENT ERROR */
2669 		buffer[0] = 0x70;
2670 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2671 		/* ABORTED COMMAND */
2672 		buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2673 		/* WRITE ERROR */
2674 		buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2675 		/* UNEXPECTED_UNSOLICITED_DATA */
2676 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2677 		break;
2678 	case TCM_SERVICE_CRC_ERROR:
2679 		/* CURRENT ERROR */
2680 		buffer[0] = 0x70;
2681 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2682 		/* ABORTED COMMAND */
2683 		buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2684 		/* PROTOCOL SERVICE CRC ERROR */
2685 		buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2686 		/* N/A */
2687 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2688 		break;
2689 	case TCM_SNACK_REJECTED:
2690 		/* CURRENT ERROR */
2691 		buffer[0] = 0x70;
2692 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2693 		/* ABORTED COMMAND */
2694 		buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2695 		/* READ ERROR */
2696 		buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2697 		/* FAILED RETRANSMISSION REQUEST */
2698 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2699 		break;
2700 	case TCM_WRITE_PROTECTED:
2701 		/* CURRENT ERROR */
2702 		buffer[0] = 0x70;
2703 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2704 		/* DATA PROTECT */
2705 		buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2706 		/* WRITE PROTECTED */
2707 		buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2708 		break;
2709 	case TCM_ADDRESS_OUT_OF_RANGE:
2710 		/* CURRENT ERROR */
2711 		buffer[0] = 0x70;
2712 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2713 		/* ILLEGAL REQUEST */
2714 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2715 		/* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2716 		buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2717 		break;
2718 	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2719 		/* CURRENT ERROR */
2720 		buffer[0] = 0x70;
2721 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2722 		/* UNIT ATTENTION */
2723 		buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2724 		core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2725 		buffer[SPC_ASC_KEY_OFFSET] = asc;
2726 		buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2727 		break;
2728 	case TCM_CHECK_CONDITION_NOT_READY:
2729 		/* CURRENT ERROR */
2730 		buffer[0] = 0x70;
2731 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2732 		/* Not Ready */
2733 		buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2734 		transport_get_sense_codes(cmd, &asc, &ascq);
2735 		buffer[SPC_ASC_KEY_OFFSET] = asc;
2736 		buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2737 		break;
2738 	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2739 	default:
2740 		/* CURRENT ERROR */
2741 		buffer[0] = 0x70;
2742 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2743 		/* ILLEGAL REQUEST */
2744 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2745 		/* LOGICAL UNIT COMMUNICATION FAILURE */
2746 		buffer[SPC_ASC_KEY_OFFSET] = 0x80;
2747 		break;
2748 	}
2749 	/*
2750 	 * This code uses linux/include/scsi/scsi.h SAM status codes!
2751 	 */
2752 	cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2753 	/*
2754 	 * Automatically padded, this value is encoded in the fabric's
2755 	 * data_length response PDU containing the SCSI defined sense data.
2756 	 */
2757 	cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2758 
2759 after_reason:
2760 	return cmd->se_tfo->queue_status(cmd);
2761 }
2762 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2763 
2764 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2765 {
2766 	if (!(cmd->transport_state & CMD_T_ABORTED))
2767 		return 0;
2768 
2769 	if (!send_status || (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
2770 		return 1;
2771 
2772 	pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2773 		 cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2774 
2775 	cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
2776 	cmd->se_tfo->queue_status(cmd);
2777 
2778 	return 1;
2779 }
2780 EXPORT_SYMBOL(transport_check_aborted_status);
2781 
2782 void transport_send_task_abort(struct se_cmd *cmd)
2783 {
2784 	unsigned long flags;
2785 
2786 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2787 	if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION | SCF_SENT_DELAYED_TAS)) {
2788 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2789 		return;
2790 	}
2791 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2792 
2793 	/*
2794 	 * If there are still expected incoming fabric WRITEs, we wait
2795 	 * until until they have completed before sending a TASK_ABORTED
2796 	 * response.  This response with TASK_ABORTED status will be
2797 	 * queued back to fabric module by transport_check_aborted_status().
2798 	 */
2799 	if (cmd->data_direction == DMA_TO_DEVICE) {
2800 		if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2801 			cmd->transport_state |= CMD_T_ABORTED;
2802 			smp_mb__after_atomic_inc();
2803 		}
2804 	}
2805 	cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2806 
2807 	pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2808 		" ITT: 0x%08x\n", cmd->t_task_cdb[0],
2809 		cmd->se_tfo->get_task_tag(cmd));
2810 
2811 	cmd->se_tfo->queue_status(cmd);
2812 }
2813 
2814 static void target_tmr_work(struct work_struct *work)
2815 {
2816 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2817 	struct se_device *dev = cmd->se_dev;
2818 	struct se_tmr_req *tmr = cmd->se_tmr_req;
2819 	int ret;
2820 
2821 	switch (tmr->function) {
2822 	case TMR_ABORT_TASK:
2823 		core_tmr_abort_task(dev, tmr, cmd->se_sess);
2824 		break;
2825 	case TMR_ABORT_TASK_SET:
2826 	case TMR_CLEAR_ACA:
2827 	case TMR_CLEAR_TASK_SET:
2828 		tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2829 		break;
2830 	case TMR_LUN_RESET:
2831 		ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2832 		tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2833 					 TMR_FUNCTION_REJECTED;
2834 		break;
2835 	case TMR_TARGET_WARM_RESET:
2836 		tmr->response = TMR_FUNCTION_REJECTED;
2837 		break;
2838 	case TMR_TARGET_COLD_RESET:
2839 		tmr->response = TMR_FUNCTION_REJECTED;
2840 		break;
2841 	default:
2842 		pr_err("Uknown TMR function: 0x%02x.\n",
2843 				tmr->function);
2844 		tmr->response = TMR_FUNCTION_REJECTED;
2845 		break;
2846 	}
2847 
2848 	cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2849 	cmd->se_tfo->queue_tm_rsp(cmd);
2850 
2851 	transport_cmd_check_stop_to_fabric(cmd);
2852 }
2853 
2854 int transport_generic_handle_tmr(
2855 	struct se_cmd *cmd)
2856 {
2857 	INIT_WORK(&cmd->work, target_tmr_work);
2858 	queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2859 	return 0;
2860 }
2861 EXPORT_SYMBOL(transport_generic_handle_tmr);
2862