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 void transport_put_cmd(struct se_cmd *cmd);
69 static void target_complete_ok_work(struct work_struct *work);
70 
71 int init_se_kmem_caches(void)
72 {
73 	se_sess_cache = kmem_cache_create("se_sess_cache",
74 			sizeof(struct se_session), __alignof__(struct se_session),
75 			0, NULL);
76 	if (!se_sess_cache) {
77 		pr_err("kmem_cache_create() for struct se_session"
78 				" failed\n");
79 		goto out;
80 	}
81 	se_ua_cache = kmem_cache_create("se_ua_cache",
82 			sizeof(struct se_ua), __alignof__(struct se_ua),
83 			0, NULL);
84 	if (!se_ua_cache) {
85 		pr_err("kmem_cache_create() for struct se_ua failed\n");
86 		goto out_free_sess_cache;
87 	}
88 	t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
89 			sizeof(struct t10_pr_registration),
90 			__alignof__(struct t10_pr_registration), 0, NULL);
91 	if (!t10_pr_reg_cache) {
92 		pr_err("kmem_cache_create() for struct t10_pr_registration"
93 				" failed\n");
94 		goto out_free_ua_cache;
95 	}
96 	t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
97 			sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
98 			0, NULL);
99 	if (!t10_alua_lu_gp_cache) {
100 		pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
101 				" failed\n");
102 		goto out_free_pr_reg_cache;
103 	}
104 	t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
105 			sizeof(struct t10_alua_lu_gp_member),
106 			__alignof__(struct t10_alua_lu_gp_member), 0, NULL);
107 	if (!t10_alua_lu_gp_mem_cache) {
108 		pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
109 				"cache failed\n");
110 		goto out_free_lu_gp_cache;
111 	}
112 	t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
113 			sizeof(struct t10_alua_tg_pt_gp),
114 			__alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
115 	if (!t10_alua_tg_pt_gp_cache) {
116 		pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
117 				"cache failed\n");
118 		goto out_free_lu_gp_mem_cache;
119 	}
120 	t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
121 			"t10_alua_tg_pt_gp_mem_cache",
122 			sizeof(struct t10_alua_tg_pt_gp_member),
123 			__alignof__(struct t10_alua_tg_pt_gp_member),
124 			0, NULL);
125 	if (!t10_alua_tg_pt_gp_mem_cache) {
126 		pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
127 				"mem_t failed\n");
128 		goto out_free_tg_pt_gp_cache;
129 	}
130 
131 	target_completion_wq = alloc_workqueue("target_completion",
132 					       WQ_MEM_RECLAIM, 0);
133 	if (!target_completion_wq)
134 		goto out_free_tg_pt_gp_mem_cache;
135 
136 	return 0;
137 
138 out_free_tg_pt_gp_mem_cache:
139 	kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
140 out_free_tg_pt_gp_cache:
141 	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
142 out_free_lu_gp_mem_cache:
143 	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
144 out_free_lu_gp_cache:
145 	kmem_cache_destroy(t10_alua_lu_gp_cache);
146 out_free_pr_reg_cache:
147 	kmem_cache_destroy(t10_pr_reg_cache);
148 out_free_ua_cache:
149 	kmem_cache_destroy(se_ua_cache);
150 out_free_sess_cache:
151 	kmem_cache_destroy(se_sess_cache);
152 out:
153 	return -ENOMEM;
154 }
155 
156 void release_se_kmem_caches(void)
157 {
158 	destroy_workqueue(target_completion_wq);
159 	kmem_cache_destroy(se_sess_cache);
160 	kmem_cache_destroy(se_ua_cache);
161 	kmem_cache_destroy(t10_pr_reg_cache);
162 	kmem_cache_destroy(t10_alua_lu_gp_cache);
163 	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
164 	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
165 	kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
166 }
167 
168 /* This code ensures unique mib indexes are handed out. */
169 static DEFINE_SPINLOCK(scsi_mib_index_lock);
170 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
171 
172 /*
173  * Allocate a new row index for the entry type specified
174  */
175 u32 scsi_get_new_index(scsi_index_t type)
176 {
177 	u32 new_index;
178 
179 	BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
180 
181 	spin_lock(&scsi_mib_index_lock);
182 	new_index = ++scsi_mib_index[type];
183 	spin_unlock(&scsi_mib_index_lock);
184 
185 	return new_index;
186 }
187 
188 void transport_subsystem_check_init(void)
189 {
190 	int ret;
191 	static int sub_api_initialized;
192 
193 	if (sub_api_initialized)
194 		return;
195 
196 	ret = request_module("target_core_iblock");
197 	if (ret != 0)
198 		pr_err("Unable to load target_core_iblock\n");
199 
200 	ret = request_module("target_core_file");
201 	if (ret != 0)
202 		pr_err("Unable to load target_core_file\n");
203 
204 	ret = request_module("target_core_pscsi");
205 	if (ret != 0)
206 		pr_err("Unable to load target_core_pscsi\n");
207 
208 	sub_api_initialized = 1;
209 }
210 
211 struct se_session *transport_init_session(void)
212 {
213 	struct se_session *se_sess;
214 
215 	se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
216 	if (!se_sess) {
217 		pr_err("Unable to allocate struct se_session from"
218 				" se_sess_cache\n");
219 		return ERR_PTR(-ENOMEM);
220 	}
221 	INIT_LIST_HEAD(&se_sess->sess_list);
222 	INIT_LIST_HEAD(&se_sess->sess_acl_list);
223 	INIT_LIST_HEAD(&se_sess->sess_cmd_list);
224 	spin_lock_init(&se_sess->sess_cmd_lock);
225 	kref_init(&se_sess->sess_kref);
226 
227 	return se_sess;
228 }
229 EXPORT_SYMBOL(transport_init_session);
230 
231 /*
232  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
233  */
234 void __transport_register_session(
235 	struct se_portal_group *se_tpg,
236 	struct se_node_acl *se_nacl,
237 	struct se_session *se_sess,
238 	void *fabric_sess_ptr)
239 {
240 	unsigned char buf[PR_REG_ISID_LEN];
241 
242 	se_sess->se_tpg = se_tpg;
243 	se_sess->fabric_sess_ptr = fabric_sess_ptr;
244 	/*
245 	 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
246 	 *
247 	 * Only set for struct se_session's that will actually be moving I/O.
248 	 * eg: *NOT* discovery sessions.
249 	 */
250 	if (se_nacl) {
251 		/*
252 		 * If the fabric module supports an ISID based TransportID,
253 		 * save this value in binary from the fabric I_T Nexus now.
254 		 */
255 		if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
256 			memset(&buf[0], 0, PR_REG_ISID_LEN);
257 			se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
258 					&buf[0], PR_REG_ISID_LEN);
259 			se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
260 		}
261 		kref_get(&se_nacl->acl_kref);
262 
263 		spin_lock_irq(&se_nacl->nacl_sess_lock);
264 		/*
265 		 * The se_nacl->nacl_sess pointer will be set to the
266 		 * last active I_T Nexus for each struct se_node_acl.
267 		 */
268 		se_nacl->nacl_sess = se_sess;
269 
270 		list_add_tail(&se_sess->sess_acl_list,
271 			      &se_nacl->acl_sess_list);
272 		spin_unlock_irq(&se_nacl->nacl_sess_lock);
273 	}
274 	list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
275 
276 	pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
277 		se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
278 }
279 EXPORT_SYMBOL(__transport_register_session);
280 
281 void transport_register_session(
282 	struct se_portal_group *se_tpg,
283 	struct se_node_acl *se_nacl,
284 	struct se_session *se_sess,
285 	void *fabric_sess_ptr)
286 {
287 	unsigned long flags;
288 
289 	spin_lock_irqsave(&se_tpg->session_lock, flags);
290 	__transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
291 	spin_unlock_irqrestore(&se_tpg->session_lock, flags);
292 }
293 EXPORT_SYMBOL(transport_register_session);
294 
295 static void target_release_session(struct kref *kref)
296 {
297 	struct se_session *se_sess = container_of(kref,
298 			struct se_session, sess_kref);
299 	struct se_portal_group *se_tpg = se_sess->se_tpg;
300 
301 	se_tpg->se_tpg_tfo->close_session(se_sess);
302 }
303 
304 void target_get_session(struct se_session *se_sess)
305 {
306 	kref_get(&se_sess->sess_kref);
307 }
308 EXPORT_SYMBOL(target_get_session);
309 
310 void target_put_session(struct se_session *se_sess)
311 {
312 	struct se_portal_group *tpg = se_sess->se_tpg;
313 
314 	if (tpg->se_tpg_tfo->put_session != NULL) {
315 		tpg->se_tpg_tfo->put_session(se_sess);
316 		return;
317 	}
318 	kref_put(&se_sess->sess_kref, target_release_session);
319 }
320 EXPORT_SYMBOL(target_put_session);
321 
322 static void target_complete_nacl(struct kref *kref)
323 {
324 	struct se_node_acl *nacl = container_of(kref,
325 				struct se_node_acl, acl_kref);
326 
327 	complete(&nacl->acl_free_comp);
328 }
329 
330 void target_put_nacl(struct se_node_acl *nacl)
331 {
332 	kref_put(&nacl->acl_kref, target_complete_nacl);
333 }
334 
335 void transport_deregister_session_configfs(struct se_session *se_sess)
336 {
337 	struct se_node_acl *se_nacl;
338 	unsigned long flags;
339 	/*
340 	 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
341 	 */
342 	se_nacl = se_sess->se_node_acl;
343 	if (se_nacl) {
344 		spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
345 		if (se_nacl->acl_stop == 0)
346 			list_del(&se_sess->sess_acl_list);
347 		/*
348 		 * If the session list is empty, then clear the pointer.
349 		 * Otherwise, set the struct se_session pointer from the tail
350 		 * element of the per struct se_node_acl active session list.
351 		 */
352 		if (list_empty(&se_nacl->acl_sess_list))
353 			se_nacl->nacl_sess = NULL;
354 		else {
355 			se_nacl->nacl_sess = container_of(
356 					se_nacl->acl_sess_list.prev,
357 					struct se_session, sess_acl_list);
358 		}
359 		spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
360 	}
361 }
362 EXPORT_SYMBOL(transport_deregister_session_configfs);
363 
364 void transport_free_session(struct se_session *se_sess)
365 {
366 	kmem_cache_free(se_sess_cache, se_sess);
367 }
368 EXPORT_SYMBOL(transport_free_session);
369 
370 void transport_deregister_session(struct se_session *se_sess)
371 {
372 	struct se_portal_group *se_tpg = se_sess->se_tpg;
373 	struct target_core_fabric_ops *se_tfo;
374 	struct se_node_acl *se_nacl;
375 	unsigned long flags;
376 	bool comp_nacl = true;
377 
378 	if (!se_tpg) {
379 		transport_free_session(se_sess);
380 		return;
381 	}
382 	se_tfo = se_tpg->se_tpg_tfo;
383 
384 	spin_lock_irqsave(&se_tpg->session_lock, flags);
385 	list_del(&se_sess->sess_list);
386 	se_sess->se_tpg = NULL;
387 	se_sess->fabric_sess_ptr = NULL;
388 	spin_unlock_irqrestore(&se_tpg->session_lock, flags);
389 
390 	/*
391 	 * Determine if we need to do extra work for this initiator node's
392 	 * struct se_node_acl if it had been previously dynamically generated.
393 	 */
394 	se_nacl = se_sess->se_node_acl;
395 
396 	spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
397 	if (se_nacl && se_nacl->dynamic_node_acl) {
398 		if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
399 			list_del(&se_nacl->acl_list);
400 			se_tpg->num_node_acls--;
401 			spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
402 			core_tpg_wait_for_nacl_pr_ref(se_nacl);
403 			core_free_device_list_for_node(se_nacl, se_tpg);
404 			se_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
405 
406 			comp_nacl = false;
407 			spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
408 		}
409 	}
410 	spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
411 
412 	pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
413 		se_tpg->se_tpg_tfo->get_fabric_name());
414 	/*
415 	 * If last kref is dropping now for an explict NodeACL, awake sleeping
416 	 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
417 	 * removal context.
418 	 */
419 	if (se_nacl && comp_nacl == true)
420 		target_put_nacl(se_nacl);
421 
422 	transport_free_session(se_sess);
423 }
424 EXPORT_SYMBOL(transport_deregister_session);
425 
426 /*
427  * Called with cmd->t_state_lock held.
428  */
429 static void target_remove_from_state_list(struct se_cmd *cmd)
430 {
431 	struct se_device *dev = cmd->se_dev;
432 	unsigned long flags;
433 
434 	if (!dev)
435 		return;
436 
437 	if (cmd->transport_state & CMD_T_BUSY)
438 		return;
439 
440 	spin_lock_irqsave(&dev->execute_task_lock, flags);
441 	if (cmd->state_active) {
442 		list_del(&cmd->state_list);
443 		cmd->state_active = false;
444 	}
445 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
446 }
447 
448 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists)
449 {
450 	unsigned long flags;
451 
452 	spin_lock_irqsave(&cmd->t_state_lock, flags);
453 	/*
454 	 * Determine if IOCTL context caller in requesting the stopping of this
455 	 * command for LUN shutdown purposes.
456 	 */
457 	if (cmd->transport_state & CMD_T_LUN_STOP) {
458 		pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
459 			__func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
460 
461 		cmd->transport_state &= ~CMD_T_ACTIVE;
462 		if (remove_from_lists)
463 			target_remove_from_state_list(cmd);
464 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
465 
466 		complete(&cmd->transport_lun_stop_comp);
467 		return 1;
468 	}
469 
470 	if (remove_from_lists) {
471 		target_remove_from_state_list(cmd);
472 
473 		/*
474 		 * Clear struct se_cmd->se_lun before the handoff to FE.
475 		 */
476 		cmd->se_lun = NULL;
477 	}
478 
479 	/*
480 	 * Determine if frontend context caller is requesting the stopping of
481 	 * this command for frontend exceptions.
482 	 */
483 	if (cmd->transport_state & CMD_T_STOP) {
484 		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
485 			__func__, __LINE__,
486 			cmd->se_tfo->get_task_tag(cmd));
487 
488 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
489 
490 		complete(&cmd->t_transport_stop_comp);
491 		return 1;
492 	}
493 
494 	cmd->transport_state &= ~CMD_T_ACTIVE;
495 	if (remove_from_lists) {
496 		/*
497 		 * Some fabric modules like tcm_loop can release
498 		 * their internally allocated I/O reference now and
499 		 * struct se_cmd now.
500 		 *
501 		 * Fabric modules are expected to return '1' here if the
502 		 * se_cmd being passed is released at this point,
503 		 * or zero if not being released.
504 		 */
505 		if (cmd->se_tfo->check_stop_free != NULL) {
506 			spin_unlock_irqrestore(&cmd->t_state_lock, flags);
507 			return cmd->se_tfo->check_stop_free(cmd);
508 		}
509 	}
510 
511 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
512 	return 0;
513 }
514 
515 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
516 {
517 	return transport_cmd_check_stop(cmd, true);
518 }
519 
520 static void transport_lun_remove_cmd(struct se_cmd *cmd)
521 {
522 	struct se_lun *lun = cmd->se_lun;
523 	unsigned long flags;
524 
525 	if (!lun)
526 		return;
527 
528 	spin_lock_irqsave(&cmd->t_state_lock, flags);
529 	if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
530 		cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
531 		target_remove_from_state_list(cmd);
532 	}
533 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
534 
535 	spin_lock_irqsave(&lun->lun_cmd_lock, flags);
536 	if (!list_empty(&cmd->se_lun_node))
537 		list_del_init(&cmd->se_lun_node);
538 	spin_unlock_irqrestore(&lun->lun_cmd_lock, flags);
539 }
540 
541 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
542 {
543 	if (transport_cmd_check_stop_to_fabric(cmd))
544 		return;
545 	if (remove)
546 		transport_put_cmd(cmd);
547 }
548 
549 static void target_complete_failure_work(struct work_struct *work)
550 {
551 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
552 
553 	transport_generic_request_failure(cmd,
554 			TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
555 }
556 
557 /*
558  * Used when asking transport to copy Sense Data from the underlying
559  * Linux/SCSI struct scsi_cmnd
560  */
561 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
562 {
563 	struct se_device *dev = cmd->se_dev;
564 
565 	WARN_ON(!cmd->se_lun);
566 
567 	if (!dev)
568 		return NULL;
569 
570 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
571 		return NULL;
572 
573 	cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
574 
575 	pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
576 		dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
577 	return cmd->sense_buffer;
578 }
579 
580 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
581 {
582 	struct se_device *dev = cmd->se_dev;
583 	int success = scsi_status == GOOD;
584 	unsigned long flags;
585 
586 	cmd->scsi_status = scsi_status;
587 
588 
589 	spin_lock_irqsave(&cmd->t_state_lock, flags);
590 	cmd->transport_state &= ~CMD_T_BUSY;
591 
592 	if (dev && dev->transport->transport_complete) {
593 		dev->transport->transport_complete(cmd,
594 				cmd->t_data_sg,
595 				transport_get_sense_buffer(cmd));
596 		if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
597 			success = 1;
598 	}
599 
600 	/*
601 	 * See if we are waiting to complete for an exception condition.
602 	 */
603 	if (cmd->transport_state & CMD_T_REQUEST_STOP) {
604 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
605 		complete(&cmd->task_stop_comp);
606 		return;
607 	}
608 
609 	if (!success)
610 		cmd->transport_state |= CMD_T_FAILED;
611 
612 	/*
613 	 * Check for case where an explict ABORT_TASK has been received
614 	 * and transport_wait_for_tasks() will be waiting for completion..
615 	 */
616 	if (cmd->transport_state & CMD_T_ABORTED &&
617 	    cmd->transport_state & CMD_T_STOP) {
618 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
619 		complete(&cmd->t_transport_stop_comp);
620 		return;
621 	} else if (cmd->transport_state & CMD_T_FAILED) {
622 		INIT_WORK(&cmd->work, target_complete_failure_work);
623 	} else {
624 		INIT_WORK(&cmd->work, target_complete_ok_work);
625 	}
626 
627 	cmd->t_state = TRANSPORT_COMPLETE;
628 	cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
629 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
630 
631 	queue_work(target_completion_wq, &cmd->work);
632 }
633 EXPORT_SYMBOL(target_complete_cmd);
634 
635 static void target_add_to_state_list(struct se_cmd *cmd)
636 {
637 	struct se_device *dev = cmd->se_dev;
638 	unsigned long flags;
639 
640 	spin_lock_irqsave(&dev->execute_task_lock, flags);
641 	if (!cmd->state_active) {
642 		list_add_tail(&cmd->state_list, &dev->state_list);
643 		cmd->state_active = true;
644 	}
645 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
646 }
647 
648 /*
649  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
650  */
651 static void transport_write_pending_qf(struct se_cmd *cmd);
652 static void transport_complete_qf(struct se_cmd *cmd);
653 
654 void target_qf_do_work(struct work_struct *work)
655 {
656 	struct se_device *dev = container_of(work, struct se_device,
657 					qf_work_queue);
658 	LIST_HEAD(qf_cmd_list);
659 	struct se_cmd *cmd, *cmd_tmp;
660 
661 	spin_lock_irq(&dev->qf_cmd_lock);
662 	list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
663 	spin_unlock_irq(&dev->qf_cmd_lock);
664 
665 	list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
666 		list_del(&cmd->se_qf_node);
667 		atomic_dec(&dev->dev_qf_count);
668 		smp_mb__after_atomic_dec();
669 
670 		pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
671 			" context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
672 			(cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
673 			(cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
674 			: "UNKNOWN");
675 
676 		if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
677 			transport_write_pending_qf(cmd);
678 		else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
679 			transport_complete_qf(cmd);
680 	}
681 }
682 
683 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
684 {
685 	switch (cmd->data_direction) {
686 	case DMA_NONE:
687 		return "NONE";
688 	case DMA_FROM_DEVICE:
689 		return "READ";
690 	case DMA_TO_DEVICE:
691 		return "WRITE";
692 	case DMA_BIDIRECTIONAL:
693 		return "BIDI";
694 	default:
695 		break;
696 	}
697 
698 	return "UNKNOWN";
699 }
700 
701 void transport_dump_dev_state(
702 	struct se_device *dev,
703 	char *b,
704 	int *bl)
705 {
706 	*bl += sprintf(b + *bl, "Status: ");
707 	if (dev->export_count)
708 		*bl += sprintf(b + *bl, "ACTIVATED");
709 	else
710 		*bl += sprintf(b + *bl, "DEACTIVATED");
711 
712 	*bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
713 	*bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
714 		dev->dev_attrib.block_size,
715 		dev->dev_attrib.hw_max_sectors);
716 	*bl += sprintf(b + *bl, "        ");
717 }
718 
719 void transport_dump_vpd_proto_id(
720 	struct t10_vpd *vpd,
721 	unsigned char *p_buf,
722 	int p_buf_len)
723 {
724 	unsigned char buf[VPD_TMP_BUF_SIZE];
725 	int len;
726 
727 	memset(buf, 0, VPD_TMP_BUF_SIZE);
728 	len = sprintf(buf, "T10 VPD Protocol Identifier: ");
729 
730 	switch (vpd->protocol_identifier) {
731 	case 0x00:
732 		sprintf(buf+len, "Fibre Channel\n");
733 		break;
734 	case 0x10:
735 		sprintf(buf+len, "Parallel SCSI\n");
736 		break;
737 	case 0x20:
738 		sprintf(buf+len, "SSA\n");
739 		break;
740 	case 0x30:
741 		sprintf(buf+len, "IEEE 1394\n");
742 		break;
743 	case 0x40:
744 		sprintf(buf+len, "SCSI Remote Direct Memory Access"
745 				" Protocol\n");
746 		break;
747 	case 0x50:
748 		sprintf(buf+len, "Internet SCSI (iSCSI)\n");
749 		break;
750 	case 0x60:
751 		sprintf(buf+len, "SAS Serial SCSI Protocol\n");
752 		break;
753 	case 0x70:
754 		sprintf(buf+len, "Automation/Drive Interface Transport"
755 				" Protocol\n");
756 		break;
757 	case 0x80:
758 		sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
759 		break;
760 	default:
761 		sprintf(buf+len, "Unknown 0x%02x\n",
762 				vpd->protocol_identifier);
763 		break;
764 	}
765 
766 	if (p_buf)
767 		strncpy(p_buf, buf, p_buf_len);
768 	else
769 		pr_debug("%s", buf);
770 }
771 
772 void
773 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
774 {
775 	/*
776 	 * Check if the Protocol Identifier Valid (PIV) bit is set..
777 	 *
778 	 * from spc3r23.pdf section 7.5.1
779 	 */
780 	 if (page_83[1] & 0x80) {
781 		vpd->protocol_identifier = (page_83[0] & 0xf0);
782 		vpd->protocol_identifier_set = 1;
783 		transport_dump_vpd_proto_id(vpd, NULL, 0);
784 	}
785 }
786 EXPORT_SYMBOL(transport_set_vpd_proto_id);
787 
788 int transport_dump_vpd_assoc(
789 	struct t10_vpd *vpd,
790 	unsigned char *p_buf,
791 	int p_buf_len)
792 {
793 	unsigned char buf[VPD_TMP_BUF_SIZE];
794 	int ret = 0;
795 	int len;
796 
797 	memset(buf, 0, VPD_TMP_BUF_SIZE);
798 	len = sprintf(buf, "T10 VPD Identifier Association: ");
799 
800 	switch (vpd->association) {
801 	case 0x00:
802 		sprintf(buf+len, "addressed logical unit\n");
803 		break;
804 	case 0x10:
805 		sprintf(buf+len, "target port\n");
806 		break;
807 	case 0x20:
808 		sprintf(buf+len, "SCSI target device\n");
809 		break;
810 	default:
811 		sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
812 		ret = -EINVAL;
813 		break;
814 	}
815 
816 	if (p_buf)
817 		strncpy(p_buf, buf, p_buf_len);
818 	else
819 		pr_debug("%s", buf);
820 
821 	return ret;
822 }
823 
824 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
825 {
826 	/*
827 	 * The VPD identification association..
828 	 *
829 	 * from spc3r23.pdf Section 7.6.3.1 Table 297
830 	 */
831 	vpd->association = (page_83[1] & 0x30);
832 	return transport_dump_vpd_assoc(vpd, NULL, 0);
833 }
834 EXPORT_SYMBOL(transport_set_vpd_assoc);
835 
836 int transport_dump_vpd_ident_type(
837 	struct t10_vpd *vpd,
838 	unsigned char *p_buf,
839 	int p_buf_len)
840 {
841 	unsigned char buf[VPD_TMP_BUF_SIZE];
842 	int ret = 0;
843 	int len;
844 
845 	memset(buf, 0, VPD_TMP_BUF_SIZE);
846 	len = sprintf(buf, "T10 VPD Identifier Type: ");
847 
848 	switch (vpd->device_identifier_type) {
849 	case 0x00:
850 		sprintf(buf+len, "Vendor specific\n");
851 		break;
852 	case 0x01:
853 		sprintf(buf+len, "T10 Vendor ID based\n");
854 		break;
855 	case 0x02:
856 		sprintf(buf+len, "EUI-64 based\n");
857 		break;
858 	case 0x03:
859 		sprintf(buf+len, "NAA\n");
860 		break;
861 	case 0x04:
862 		sprintf(buf+len, "Relative target port identifier\n");
863 		break;
864 	case 0x08:
865 		sprintf(buf+len, "SCSI name string\n");
866 		break;
867 	default:
868 		sprintf(buf+len, "Unsupported: 0x%02x\n",
869 				vpd->device_identifier_type);
870 		ret = -EINVAL;
871 		break;
872 	}
873 
874 	if (p_buf) {
875 		if (p_buf_len < strlen(buf)+1)
876 			return -EINVAL;
877 		strncpy(p_buf, buf, p_buf_len);
878 	} else {
879 		pr_debug("%s", buf);
880 	}
881 
882 	return ret;
883 }
884 
885 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
886 {
887 	/*
888 	 * The VPD identifier type..
889 	 *
890 	 * from spc3r23.pdf Section 7.6.3.1 Table 298
891 	 */
892 	vpd->device_identifier_type = (page_83[1] & 0x0f);
893 	return transport_dump_vpd_ident_type(vpd, NULL, 0);
894 }
895 EXPORT_SYMBOL(transport_set_vpd_ident_type);
896 
897 int transport_dump_vpd_ident(
898 	struct t10_vpd *vpd,
899 	unsigned char *p_buf,
900 	int p_buf_len)
901 {
902 	unsigned char buf[VPD_TMP_BUF_SIZE];
903 	int ret = 0;
904 
905 	memset(buf, 0, VPD_TMP_BUF_SIZE);
906 
907 	switch (vpd->device_identifier_code_set) {
908 	case 0x01: /* Binary */
909 		snprintf(buf, sizeof(buf),
910 			"T10 VPD Binary Device Identifier: %s\n",
911 			&vpd->device_identifier[0]);
912 		break;
913 	case 0x02: /* ASCII */
914 		snprintf(buf, sizeof(buf),
915 			"T10 VPD ASCII Device Identifier: %s\n",
916 			&vpd->device_identifier[0]);
917 		break;
918 	case 0x03: /* UTF-8 */
919 		snprintf(buf, sizeof(buf),
920 			"T10 VPD UTF-8 Device Identifier: %s\n",
921 			&vpd->device_identifier[0]);
922 		break;
923 	default:
924 		sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
925 			" 0x%02x", vpd->device_identifier_code_set);
926 		ret = -EINVAL;
927 		break;
928 	}
929 
930 	if (p_buf)
931 		strncpy(p_buf, buf, p_buf_len);
932 	else
933 		pr_debug("%s", buf);
934 
935 	return ret;
936 }
937 
938 int
939 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
940 {
941 	static const char hex_str[] = "0123456789abcdef";
942 	int j = 0, i = 4; /* offset to start of the identifier */
943 
944 	/*
945 	 * The VPD Code Set (encoding)
946 	 *
947 	 * from spc3r23.pdf Section 7.6.3.1 Table 296
948 	 */
949 	vpd->device_identifier_code_set = (page_83[0] & 0x0f);
950 	switch (vpd->device_identifier_code_set) {
951 	case 0x01: /* Binary */
952 		vpd->device_identifier[j++] =
953 				hex_str[vpd->device_identifier_type];
954 		while (i < (4 + page_83[3])) {
955 			vpd->device_identifier[j++] =
956 				hex_str[(page_83[i] & 0xf0) >> 4];
957 			vpd->device_identifier[j++] =
958 				hex_str[page_83[i] & 0x0f];
959 			i++;
960 		}
961 		break;
962 	case 0x02: /* ASCII */
963 	case 0x03: /* UTF-8 */
964 		while (i < (4 + page_83[3]))
965 			vpd->device_identifier[j++] = page_83[i++];
966 		break;
967 	default:
968 		break;
969 	}
970 
971 	return transport_dump_vpd_ident(vpd, NULL, 0);
972 }
973 EXPORT_SYMBOL(transport_set_vpd_ident);
974 
975 sense_reason_t
976 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
977 {
978 	struct se_device *dev = cmd->se_dev;
979 
980 	if (cmd->unknown_data_length) {
981 		cmd->data_length = size;
982 	} else if (size != cmd->data_length) {
983 		pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
984 			" %u does not match SCSI CDB Length: %u for SAM Opcode:"
985 			" 0x%02x\n", cmd->se_tfo->get_fabric_name(),
986 				cmd->data_length, size, cmd->t_task_cdb[0]);
987 
988 		if (cmd->data_direction == DMA_TO_DEVICE) {
989 			pr_err("Rejecting underflow/overflow"
990 					" WRITE data\n");
991 			return TCM_INVALID_CDB_FIELD;
992 		}
993 		/*
994 		 * Reject READ_* or WRITE_* with overflow/underflow for
995 		 * type SCF_SCSI_DATA_CDB.
996 		 */
997 		if (dev->dev_attrib.block_size != 512)  {
998 			pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
999 				" CDB on non 512-byte sector setup subsystem"
1000 				" plugin: %s\n", dev->transport->name);
1001 			/* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1002 			return TCM_INVALID_CDB_FIELD;
1003 		}
1004 		/*
1005 		 * For the overflow case keep the existing fabric provided
1006 		 * ->data_length.  Otherwise for the underflow case, reset
1007 		 * ->data_length to the smaller SCSI expected data transfer
1008 		 * length.
1009 		 */
1010 		if (size > cmd->data_length) {
1011 			cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1012 			cmd->residual_count = (size - cmd->data_length);
1013 		} else {
1014 			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1015 			cmd->residual_count = (cmd->data_length - size);
1016 			cmd->data_length = size;
1017 		}
1018 	}
1019 
1020 	return 0;
1021 
1022 }
1023 
1024 /*
1025  * Used by fabric modules containing a local struct se_cmd within their
1026  * fabric dependent per I/O descriptor.
1027  */
1028 void transport_init_se_cmd(
1029 	struct se_cmd *cmd,
1030 	struct target_core_fabric_ops *tfo,
1031 	struct se_session *se_sess,
1032 	u32 data_length,
1033 	int data_direction,
1034 	int task_attr,
1035 	unsigned char *sense_buffer)
1036 {
1037 	INIT_LIST_HEAD(&cmd->se_lun_node);
1038 	INIT_LIST_HEAD(&cmd->se_delayed_node);
1039 	INIT_LIST_HEAD(&cmd->se_qf_node);
1040 	INIT_LIST_HEAD(&cmd->se_cmd_list);
1041 	INIT_LIST_HEAD(&cmd->state_list);
1042 	init_completion(&cmd->transport_lun_fe_stop_comp);
1043 	init_completion(&cmd->transport_lun_stop_comp);
1044 	init_completion(&cmd->t_transport_stop_comp);
1045 	init_completion(&cmd->cmd_wait_comp);
1046 	init_completion(&cmd->task_stop_comp);
1047 	spin_lock_init(&cmd->t_state_lock);
1048 	cmd->transport_state = CMD_T_DEV_ACTIVE;
1049 
1050 	cmd->se_tfo = tfo;
1051 	cmd->se_sess = se_sess;
1052 	cmd->data_length = data_length;
1053 	cmd->data_direction = data_direction;
1054 	cmd->sam_task_attr = task_attr;
1055 	cmd->sense_buffer = sense_buffer;
1056 
1057 	cmd->state_active = false;
1058 }
1059 EXPORT_SYMBOL(transport_init_se_cmd);
1060 
1061 static sense_reason_t
1062 transport_check_alloc_task_attr(struct se_cmd *cmd)
1063 {
1064 	struct se_device *dev = cmd->se_dev;
1065 
1066 	/*
1067 	 * Check if SAM Task Attribute emulation is enabled for this
1068 	 * struct se_device storage object
1069 	 */
1070 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1071 		return 0;
1072 
1073 	if (cmd->sam_task_attr == MSG_ACA_TAG) {
1074 		pr_debug("SAM Task Attribute ACA"
1075 			" emulation is not supported\n");
1076 		return TCM_INVALID_CDB_FIELD;
1077 	}
1078 	/*
1079 	 * Used to determine when ORDERED commands should go from
1080 	 * Dormant to Active status.
1081 	 */
1082 	cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1083 	smp_mb__after_atomic_inc();
1084 	pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1085 			cmd->se_ordered_id, cmd->sam_task_attr,
1086 			dev->transport->name);
1087 	return 0;
1088 }
1089 
1090 sense_reason_t
1091 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1092 {
1093 	struct se_device *dev = cmd->se_dev;
1094 	unsigned long flags;
1095 	sense_reason_t ret;
1096 
1097 	/*
1098 	 * Ensure that the received CDB is less than the max (252 + 8) bytes
1099 	 * for VARIABLE_LENGTH_CMD
1100 	 */
1101 	if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1102 		pr_err("Received SCSI CDB with command_size: %d that"
1103 			" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1104 			scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1105 		return TCM_INVALID_CDB_FIELD;
1106 	}
1107 	/*
1108 	 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1109 	 * allocate the additional extended CDB buffer now..  Otherwise
1110 	 * setup the pointer from __t_task_cdb to t_task_cdb.
1111 	 */
1112 	if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1113 		cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1114 						GFP_KERNEL);
1115 		if (!cmd->t_task_cdb) {
1116 			pr_err("Unable to allocate cmd->t_task_cdb"
1117 				" %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1118 				scsi_command_size(cdb),
1119 				(unsigned long)sizeof(cmd->__t_task_cdb));
1120 			return TCM_OUT_OF_RESOURCES;
1121 		}
1122 	} else
1123 		cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1124 	/*
1125 	 * Copy the original CDB into cmd->
1126 	 */
1127 	memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1128 
1129 	/*
1130 	 * Check for an existing UNIT ATTENTION condition
1131 	 */
1132 	ret = target_scsi3_ua_check(cmd);
1133 	if (ret)
1134 		return ret;
1135 
1136 	ret = target_alua_state_check(cmd);
1137 	if (ret)
1138 		return ret;
1139 
1140 	ret = target_check_reservation(cmd);
1141 	if (ret) {
1142 		cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1143 		return ret;
1144 	}
1145 
1146 	ret = dev->transport->parse_cdb(cmd);
1147 	if (ret)
1148 		return ret;
1149 
1150 	ret = transport_check_alloc_task_attr(cmd);
1151 	if (ret)
1152 		return ret;
1153 
1154 	spin_lock_irqsave(&cmd->t_state_lock, flags);
1155 	cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1156 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1157 
1158 	spin_lock(&cmd->se_lun->lun_sep_lock);
1159 	if (cmd->se_lun->lun_sep)
1160 		cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1161 	spin_unlock(&cmd->se_lun->lun_sep_lock);
1162 	return 0;
1163 }
1164 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1165 
1166 /*
1167  * Used by fabric module frontends to queue tasks directly.
1168  * Many only be used from process context only
1169  */
1170 int transport_handle_cdb_direct(
1171 	struct se_cmd *cmd)
1172 {
1173 	sense_reason_t ret;
1174 
1175 	if (!cmd->se_lun) {
1176 		dump_stack();
1177 		pr_err("cmd->se_lun is NULL\n");
1178 		return -EINVAL;
1179 	}
1180 	if (in_interrupt()) {
1181 		dump_stack();
1182 		pr_err("transport_generic_handle_cdb cannot be called"
1183 				" from interrupt context\n");
1184 		return -EINVAL;
1185 	}
1186 	/*
1187 	 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1188 	 * outstanding descriptors are handled correctly during shutdown via
1189 	 * transport_wait_for_tasks()
1190 	 *
1191 	 * Also, we don't take cmd->t_state_lock here as we only expect
1192 	 * this to be called for initial descriptor submission.
1193 	 */
1194 	cmd->t_state = TRANSPORT_NEW_CMD;
1195 	cmd->transport_state |= CMD_T_ACTIVE;
1196 
1197 	/*
1198 	 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1199 	 * so follow TRANSPORT_NEW_CMD processing thread context usage
1200 	 * and call transport_generic_request_failure() if necessary..
1201 	 */
1202 	ret = transport_generic_new_cmd(cmd);
1203 	if (ret)
1204 		transport_generic_request_failure(cmd, ret);
1205 	return 0;
1206 }
1207 EXPORT_SYMBOL(transport_handle_cdb_direct);
1208 
1209 static sense_reason_t
1210 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1211 		u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1212 {
1213 	if (!sgl || !sgl_count)
1214 		return 0;
1215 
1216 	/*
1217 	 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1218 	 * scatterlists already have been set to follow what the fabric
1219 	 * passes for the original expected data transfer length.
1220 	 */
1221 	if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1222 		pr_warn("Rejecting SCSI DATA overflow for fabric using"
1223 			" SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1224 		return TCM_INVALID_CDB_FIELD;
1225 	}
1226 
1227 	cmd->t_data_sg = sgl;
1228 	cmd->t_data_nents = sgl_count;
1229 
1230 	if (sgl_bidi && sgl_bidi_count) {
1231 		cmd->t_bidi_data_sg = sgl_bidi;
1232 		cmd->t_bidi_data_nents = sgl_bidi_count;
1233 	}
1234 	cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1235 	return 0;
1236 }
1237 
1238 /*
1239  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1240  * 			 se_cmd + use pre-allocated SGL memory.
1241  *
1242  * @se_cmd: command descriptor to submit
1243  * @se_sess: associated se_sess for endpoint
1244  * @cdb: pointer to SCSI CDB
1245  * @sense: pointer to SCSI sense buffer
1246  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1247  * @data_length: fabric expected data transfer length
1248  * @task_addr: SAM task attribute
1249  * @data_dir: DMA data direction
1250  * @flags: flags for command submission from target_sc_flags_tables
1251  * @sgl: struct scatterlist memory for unidirectional mapping
1252  * @sgl_count: scatterlist count for unidirectional mapping
1253  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1254  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1255  *
1256  * Returns non zero to signal active I/O shutdown failure.  All other
1257  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1258  * but still return zero here.
1259  *
1260  * This may only be called from process context, and also currently
1261  * assumes internal allocation of fabric payload buffer by target-core.
1262  */
1263 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1264 		unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1265 		u32 data_length, int task_attr, int data_dir, int flags,
1266 		struct scatterlist *sgl, u32 sgl_count,
1267 		struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1268 {
1269 	struct se_portal_group *se_tpg;
1270 	sense_reason_t rc;
1271 	int ret;
1272 
1273 	se_tpg = se_sess->se_tpg;
1274 	BUG_ON(!se_tpg);
1275 	BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1276 	BUG_ON(in_interrupt());
1277 	/*
1278 	 * Initialize se_cmd for target operation.  From this point
1279 	 * exceptions are handled by sending exception status via
1280 	 * target_core_fabric_ops->queue_status() callback
1281 	 */
1282 	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1283 				data_length, data_dir, task_attr, sense);
1284 	if (flags & TARGET_SCF_UNKNOWN_SIZE)
1285 		se_cmd->unknown_data_length = 1;
1286 	/*
1287 	 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1288 	 * se_sess->sess_cmd_list.  A second kref_get here is necessary
1289 	 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1290 	 * kref_put() to happen during fabric packet acknowledgement.
1291 	 */
1292 	ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1293 	if (ret)
1294 		return ret;
1295 	/*
1296 	 * Signal bidirectional data payloads to target-core
1297 	 */
1298 	if (flags & TARGET_SCF_BIDI_OP)
1299 		se_cmd->se_cmd_flags |= SCF_BIDI;
1300 	/*
1301 	 * Locate se_lun pointer and attach it to struct se_cmd
1302 	 */
1303 	rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1304 	if (rc) {
1305 		transport_send_check_condition_and_sense(se_cmd, rc, 0);
1306 		target_put_sess_cmd(se_sess, se_cmd);
1307 		return 0;
1308 	}
1309 
1310 	rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1311 	if (rc != 0) {
1312 		transport_generic_request_failure(se_cmd, rc);
1313 		return 0;
1314 	}
1315 	/*
1316 	 * When a non zero sgl_count has been passed perform SGL passthrough
1317 	 * mapping for pre-allocated fabric memory instead of having target
1318 	 * core perform an internal SGL allocation..
1319 	 */
1320 	if (sgl_count != 0) {
1321 		BUG_ON(!sgl);
1322 
1323 		/*
1324 		 * A work-around for tcm_loop as some userspace code via
1325 		 * scsi-generic do not memset their associated read buffers,
1326 		 * so go ahead and do that here for type non-data CDBs.  Also
1327 		 * note that this is currently guaranteed to be a single SGL
1328 		 * for this case by target core in target_setup_cmd_from_cdb()
1329 		 * -> transport_generic_cmd_sequencer().
1330 		 */
1331 		if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1332 		     se_cmd->data_direction == DMA_FROM_DEVICE) {
1333 			unsigned char *buf = NULL;
1334 
1335 			if (sgl)
1336 				buf = kmap(sg_page(sgl)) + sgl->offset;
1337 
1338 			if (buf) {
1339 				memset(buf, 0, sgl->length);
1340 				kunmap(sg_page(sgl));
1341 			}
1342 		}
1343 
1344 		rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1345 				sgl_bidi, sgl_bidi_count);
1346 		if (rc != 0) {
1347 			transport_generic_request_failure(se_cmd, rc);
1348 			return 0;
1349 		}
1350 	}
1351 	/*
1352 	 * Check if we need to delay processing because of ALUA
1353 	 * Active/NonOptimized primary access state..
1354 	 */
1355 	core_alua_check_nonop_delay(se_cmd);
1356 
1357 	transport_handle_cdb_direct(se_cmd);
1358 	return 0;
1359 }
1360 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1361 
1362 /*
1363  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1364  *
1365  * @se_cmd: command descriptor to submit
1366  * @se_sess: associated se_sess for endpoint
1367  * @cdb: pointer to SCSI CDB
1368  * @sense: pointer to SCSI sense buffer
1369  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1370  * @data_length: fabric expected data transfer length
1371  * @task_addr: SAM task attribute
1372  * @data_dir: DMA data direction
1373  * @flags: flags for command submission from target_sc_flags_tables
1374  *
1375  * Returns non zero to signal active I/O shutdown failure.  All other
1376  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1377  * but still return zero here.
1378  *
1379  * This may only be called from process context, and also currently
1380  * assumes internal allocation of fabric payload buffer by target-core.
1381  *
1382  * It also assumes interal target core SGL memory allocation.
1383  */
1384 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1385 		unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1386 		u32 data_length, int task_attr, int data_dir, int flags)
1387 {
1388 	return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1389 			unpacked_lun, data_length, task_attr, data_dir,
1390 			flags, NULL, 0, NULL, 0);
1391 }
1392 EXPORT_SYMBOL(target_submit_cmd);
1393 
1394 static void target_complete_tmr_failure(struct work_struct *work)
1395 {
1396 	struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1397 
1398 	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1399 	se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1400 
1401 	transport_cmd_check_stop_to_fabric(se_cmd);
1402 }
1403 
1404 /**
1405  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1406  *                     for TMR CDBs
1407  *
1408  * @se_cmd: command descriptor to submit
1409  * @se_sess: associated se_sess for endpoint
1410  * @sense: pointer to SCSI sense buffer
1411  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1412  * @fabric_context: fabric context for TMR req
1413  * @tm_type: Type of TM request
1414  * @gfp: gfp type for caller
1415  * @tag: referenced task tag for TMR_ABORT_TASK
1416  * @flags: submit cmd flags
1417  *
1418  * Callable from all contexts.
1419  **/
1420 
1421 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1422 		unsigned char *sense, u32 unpacked_lun,
1423 		void *fabric_tmr_ptr, unsigned char tm_type,
1424 		gfp_t gfp, unsigned int tag, int flags)
1425 {
1426 	struct se_portal_group *se_tpg;
1427 	int ret;
1428 
1429 	se_tpg = se_sess->se_tpg;
1430 	BUG_ON(!se_tpg);
1431 
1432 	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1433 			      0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1434 	/*
1435 	 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1436 	 * allocation failure.
1437 	 */
1438 	ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1439 	if (ret < 0)
1440 		return -ENOMEM;
1441 
1442 	if (tm_type == TMR_ABORT_TASK)
1443 		se_cmd->se_tmr_req->ref_task_tag = tag;
1444 
1445 	/* See target_submit_cmd for commentary */
1446 	ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1447 	if (ret) {
1448 		core_tmr_release_req(se_cmd->se_tmr_req);
1449 		return ret;
1450 	}
1451 
1452 	ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1453 	if (ret) {
1454 		/*
1455 		 * For callback during failure handling, push this work off
1456 		 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1457 		 */
1458 		INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1459 		schedule_work(&se_cmd->work);
1460 		return 0;
1461 	}
1462 	transport_generic_handle_tmr(se_cmd);
1463 	return 0;
1464 }
1465 EXPORT_SYMBOL(target_submit_tmr);
1466 
1467 /*
1468  * If the cmd is active, request it to be stopped and sleep until it
1469  * has completed.
1470  */
1471 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1472 {
1473 	bool was_active = false;
1474 
1475 	if (cmd->transport_state & CMD_T_BUSY) {
1476 		cmd->transport_state |= CMD_T_REQUEST_STOP;
1477 		spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1478 
1479 		pr_debug("cmd %p waiting to complete\n", cmd);
1480 		wait_for_completion(&cmd->task_stop_comp);
1481 		pr_debug("cmd %p stopped successfully\n", cmd);
1482 
1483 		spin_lock_irqsave(&cmd->t_state_lock, *flags);
1484 		cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1485 		cmd->transport_state &= ~CMD_T_BUSY;
1486 		was_active = true;
1487 	}
1488 
1489 	return was_active;
1490 }
1491 
1492 /*
1493  * Handle SAM-esque emulation for generic transport request failures.
1494  */
1495 void transport_generic_request_failure(struct se_cmd *cmd,
1496 		sense_reason_t sense_reason)
1497 {
1498 	int ret = 0;
1499 
1500 	pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1501 		" CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1502 		cmd->t_task_cdb[0]);
1503 	pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1504 		cmd->se_tfo->get_cmd_state(cmd),
1505 		cmd->t_state, sense_reason);
1506 	pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1507 		(cmd->transport_state & CMD_T_ACTIVE) != 0,
1508 		(cmd->transport_state & CMD_T_STOP) != 0,
1509 		(cmd->transport_state & CMD_T_SENT) != 0);
1510 
1511 	/*
1512 	 * For SAM Task Attribute emulation for failed struct se_cmd
1513 	 */
1514 	transport_complete_task_attr(cmd);
1515 
1516 	switch (sense_reason) {
1517 	case TCM_NON_EXISTENT_LUN:
1518 	case TCM_UNSUPPORTED_SCSI_OPCODE:
1519 	case TCM_INVALID_CDB_FIELD:
1520 	case TCM_INVALID_PARAMETER_LIST:
1521 	case TCM_PARAMETER_LIST_LENGTH_ERROR:
1522 	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1523 	case TCM_UNKNOWN_MODE_PAGE:
1524 	case TCM_WRITE_PROTECTED:
1525 	case TCM_ADDRESS_OUT_OF_RANGE:
1526 	case TCM_CHECK_CONDITION_ABORT_CMD:
1527 	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1528 	case TCM_CHECK_CONDITION_NOT_READY:
1529 		break;
1530 	case TCM_OUT_OF_RESOURCES:
1531 		sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1532 		break;
1533 	case TCM_RESERVATION_CONFLICT:
1534 		/*
1535 		 * No SENSE Data payload for this case, set SCSI Status
1536 		 * and queue the response to $FABRIC_MOD.
1537 		 *
1538 		 * Uses linux/include/scsi/scsi.h SAM status codes defs
1539 		 */
1540 		cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1541 		/*
1542 		 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1543 		 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1544 		 * CONFLICT STATUS.
1545 		 *
1546 		 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1547 		 */
1548 		if (cmd->se_sess &&
1549 		    cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1550 			core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1551 				cmd->orig_fe_lun, 0x2C,
1552 				ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1553 
1554 		ret = cmd->se_tfo->queue_status(cmd);
1555 		if (ret == -EAGAIN || ret == -ENOMEM)
1556 			goto queue_full;
1557 		goto check_stop;
1558 	default:
1559 		pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1560 			cmd->t_task_cdb[0], sense_reason);
1561 		sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1562 		break;
1563 	}
1564 
1565 	ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1566 	if (ret == -EAGAIN || ret == -ENOMEM)
1567 		goto queue_full;
1568 
1569 check_stop:
1570 	transport_lun_remove_cmd(cmd);
1571 	if (!transport_cmd_check_stop_to_fabric(cmd))
1572 		;
1573 	return;
1574 
1575 queue_full:
1576 	cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1577 	transport_handle_queue_full(cmd, cmd->se_dev);
1578 }
1579 EXPORT_SYMBOL(transport_generic_request_failure);
1580 
1581 static void __target_execute_cmd(struct se_cmd *cmd)
1582 {
1583 	sense_reason_t ret;
1584 
1585 	spin_lock_irq(&cmd->t_state_lock);
1586 	cmd->transport_state |= (CMD_T_BUSY|CMD_T_SENT);
1587 	spin_unlock_irq(&cmd->t_state_lock);
1588 
1589 	if (cmd->execute_cmd) {
1590 		ret = cmd->execute_cmd(cmd);
1591 		if (ret) {
1592 			spin_lock_irq(&cmd->t_state_lock);
1593 			cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1594 			spin_unlock_irq(&cmd->t_state_lock);
1595 
1596 			transport_generic_request_failure(cmd, ret);
1597 		}
1598 	}
1599 }
1600 
1601 static bool target_handle_task_attr(struct se_cmd *cmd)
1602 {
1603 	struct se_device *dev = cmd->se_dev;
1604 
1605 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1606 		return false;
1607 
1608 	/*
1609 	 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1610 	 * to allow the passed struct se_cmd list of tasks to the front of the list.
1611 	 */
1612 	switch (cmd->sam_task_attr) {
1613 	case MSG_HEAD_TAG:
1614 		pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1615 			 "se_ordered_id: %u\n",
1616 			 cmd->t_task_cdb[0], cmd->se_ordered_id);
1617 		return false;
1618 	case MSG_ORDERED_TAG:
1619 		atomic_inc(&dev->dev_ordered_sync);
1620 		smp_mb__after_atomic_inc();
1621 
1622 		pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1623 			 " se_ordered_id: %u\n",
1624 			 cmd->t_task_cdb[0], cmd->se_ordered_id);
1625 
1626 		/*
1627 		 * Execute an ORDERED command if no other older commands
1628 		 * exist that need to be completed first.
1629 		 */
1630 		if (!atomic_read(&dev->simple_cmds))
1631 			return false;
1632 		break;
1633 	default:
1634 		/*
1635 		 * For SIMPLE and UNTAGGED Task Attribute commands
1636 		 */
1637 		atomic_inc(&dev->simple_cmds);
1638 		smp_mb__after_atomic_inc();
1639 		break;
1640 	}
1641 
1642 	if (atomic_read(&dev->dev_ordered_sync) == 0)
1643 		return false;
1644 
1645 	spin_lock(&dev->delayed_cmd_lock);
1646 	list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1647 	spin_unlock(&dev->delayed_cmd_lock);
1648 
1649 	pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1650 		" delayed CMD list, se_ordered_id: %u\n",
1651 		cmd->t_task_cdb[0], cmd->sam_task_attr,
1652 		cmd->se_ordered_id);
1653 	return true;
1654 }
1655 
1656 void target_execute_cmd(struct se_cmd *cmd)
1657 {
1658 	/*
1659 	 * If the received CDB has aleady been aborted stop processing it here.
1660 	 */
1661 	if (transport_check_aborted_status(cmd, 1)) {
1662 		complete(&cmd->transport_lun_stop_comp);
1663 		return;
1664 	}
1665 
1666 	/*
1667 	 * Determine if IOCTL context caller in requesting the stopping of this
1668 	 * command for LUN shutdown purposes.
1669 	 */
1670 	spin_lock_irq(&cmd->t_state_lock);
1671 	if (cmd->transport_state & CMD_T_LUN_STOP) {
1672 		pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
1673 			__func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
1674 
1675 		cmd->transport_state &= ~CMD_T_ACTIVE;
1676 		spin_unlock_irq(&cmd->t_state_lock);
1677 		complete(&cmd->transport_lun_stop_comp);
1678 		return;
1679 	}
1680 	/*
1681 	 * Determine if frontend context caller is requesting the stopping of
1682 	 * this command for frontend exceptions.
1683 	 */
1684 	if (cmd->transport_state & CMD_T_STOP) {
1685 		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1686 			__func__, __LINE__,
1687 			cmd->se_tfo->get_task_tag(cmd));
1688 
1689 		spin_unlock_irq(&cmd->t_state_lock);
1690 		complete(&cmd->t_transport_stop_comp);
1691 		return;
1692 	}
1693 
1694 	cmd->t_state = TRANSPORT_PROCESSING;
1695 	cmd->transport_state |= CMD_T_ACTIVE;
1696 	spin_unlock_irq(&cmd->t_state_lock);
1697 
1698 	if (!target_handle_task_attr(cmd))
1699 		__target_execute_cmd(cmd);
1700 }
1701 EXPORT_SYMBOL(target_execute_cmd);
1702 
1703 /*
1704  * Process all commands up to the last received ORDERED task attribute which
1705  * requires another blocking boundary
1706  */
1707 static void target_restart_delayed_cmds(struct se_device *dev)
1708 {
1709 	for (;;) {
1710 		struct se_cmd *cmd;
1711 
1712 		spin_lock(&dev->delayed_cmd_lock);
1713 		if (list_empty(&dev->delayed_cmd_list)) {
1714 			spin_unlock(&dev->delayed_cmd_lock);
1715 			break;
1716 		}
1717 
1718 		cmd = list_entry(dev->delayed_cmd_list.next,
1719 				 struct se_cmd, se_delayed_node);
1720 		list_del(&cmd->se_delayed_node);
1721 		spin_unlock(&dev->delayed_cmd_lock);
1722 
1723 		__target_execute_cmd(cmd);
1724 
1725 		if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1726 			break;
1727 	}
1728 }
1729 
1730 /*
1731  * Called from I/O completion to determine which dormant/delayed
1732  * and ordered cmds need to have their tasks added to the execution queue.
1733  */
1734 static void transport_complete_task_attr(struct se_cmd *cmd)
1735 {
1736 	struct se_device *dev = cmd->se_dev;
1737 
1738 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1739 		return;
1740 
1741 	if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1742 		atomic_dec(&dev->simple_cmds);
1743 		smp_mb__after_atomic_dec();
1744 		dev->dev_cur_ordered_id++;
1745 		pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1746 			" SIMPLE: %u\n", dev->dev_cur_ordered_id,
1747 			cmd->se_ordered_id);
1748 	} else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1749 		dev->dev_cur_ordered_id++;
1750 		pr_debug("Incremented dev_cur_ordered_id: %u for"
1751 			" HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1752 			cmd->se_ordered_id);
1753 	} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1754 		atomic_dec(&dev->dev_ordered_sync);
1755 		smp_mb__after_atomic_dec();
1756 
1757 		dev->dev_cur_ordered_id++;
1758 		pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1759 			" %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1760 	}
1761 
1762 	target_restart_delayed_cmds(dev);
1763 }
1764 
1765 static void transport_complete_qf(struct se_cmd *cmd)
1766 {
1767 	int ret = 0;
1768 
1769 	transport_complete_task_attr(cmd);
1770 
1771 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1772 		ret = cmd->se_tfo->queue_status(cmd);
1773 		if (ret)
1774 			goto out;
1775 	}
1776 
1777 	switch (cmd->data_direction) {
1778 	case DMA_FROM_DEVICE:
1779 		ret = cmd->se_tfo->queue_data_in(cmd);
1780 		break;
1781 	case DMA_TO_DEVICE:
1782 		if (cmd->t_bidi_data_sg) {
1783 			ret = cmd->se_tfo->queue_data_in(cmd);
1784 			if (ret < 0)
1785 				break;
1786 		}
1787 		/* Fall through for DMA_TO_DEVICE */
1788 	case DMA_NONE:
1789 		ret = cmd->se_tfo->queue_status(cmd);
1790 		break;
1791 	default:
1792 		break;
1793 	}
1794 
1795 out:
1796 	if (ret < 0) {
1797 		transport_handle_queue_full(cmd, cmd->se_dev);
1798 		return;
1799 	}
1800 	transport_lun_remove_cmd(cmd);
1801 	transport_cmd_check_stop_to_fabric(cmd);
1802 }
1803 
1804 static void transport_handle_queue_full(
1805 	struct se_cmd *cmd,
1806 	struct se_device *dev)
1807 {
1808 	spin_lock_irq(&dev->qf_cmd_lock);
1809 	list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1810 	atomic_inc(&dev->dev_qf_count);
1811 	smp_mb__after_atomic_inc();
1812 	spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1813 
1814 	schedule_work(&cmd->se_dev->qf_work_queue);
1815 }
1816 
1817 static void target_complete_ok_work(struct work_struct *work)
1818 {
1819 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1820 	int ret;
1821 
1822 	/*
1823 	 * Check if we need to move delayed/dormant tasks from cmds on the
1824 	 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1825 	 * Attribute.
1826 	 */
1827 	transport_complete_task_attr(cmd);
1828 
1829 	/*
1830 	 * Check to schedule QUEUE_FULL work, or execute an existing
1831 	 * cmd->transport_qf_callback()
1832 	 */
1833 	if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1834 		schedule_work(&cmd->se_dev->qf_work_queue);
1835 
1836 	/*
1837 	 * Check if we need to send a sense buffer from
1838 	 * the struct se_cmd in question.
1839 	 */
1840 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1841 		WARN_ON(!cmd->scsi_status);
1842 		ret = transport_send_check_condition_and_sense(
1843 					cmd, 0, 1);
1844 		if (ret == -EAGAIN || ret == -ENOMEM)
1845 			goto queue_full;
1846 
1847 		transport_lun_remove_cmd(cmd);
1848 		transport_cmd_check_stop_to_fabric(cmd);
1849 		return;
1850 	}
1851 	/*
1852 	 * Check for a callback, used by amongst other things
1853 	 * XDWRITE_READ_10 emulation.
1854 	 */
1855 	if (cmd->transport_complete_callback)
1856 		cmd->transport_complete_callback(cmd);
1857 
1858 	switch (cmd->data_direction) {
1859 	case DMA_FROM_DEVICE:
1860 		spin_lock(&cmd->se_lun->lun_sep_lock);
1861 		if (cmd->se_lun->lun_sep) {
1862 			cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1863 					cmd->data_length;
1864 		}
1865 		spin_unlock(&cmd->se_lun->lun_sep_lock);
1866 
1867 		ret = cmd->se_tfo->queue_data_in(cmd);
1868 		if (ret == -EAGAIN || ret == -ENOMEM)
1869 			goto queue_full;
1870 		break;
1871 	case DMA_TO_DEVICE:
1872 		spin_lock(&cmd->se_lun->lun_sep_lock);
1873 		if (cmd->se_lun->lun_sep) {
1874 			cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
1875 				cmd->data_length;
1876 		}
1877 		spin_unlock(&cmd->se_lun->lun_sep_lock);
1878 		/*
1879 		 * Check if we need to send READ payload for BIDI-COMMAND
1880 		 */
1881 		if (cmd->t_bidi_data_sg) {
1882 			spin_lock(&cmd->se_lun->lun_sep_lock);
1883 			if (cmd->se_lun->lun_sep) {
1884 				cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1885 					cmd->data_length;
1886 			}
1887 			spin_unlock(&cmd->se_lun->lun_sep_lock);
1888 			ret = cmd->se_tfo->queue_data_in(cmd);
1889 			if (ret == -EAGAIN || ret == -ENOMEM)
1890 				goto queue_full;
1891 			break;
1892 		}
1893 		/* Fall through for DMA_TO_DEVICE */
1894 	case DMA_NONE:
1895 		ret = cmd->se_tfo->queue_status(cmd);
1896 		if (ret == -EAGAIN || ret == -ENOMEM)
1897 			goto queue_full;
1898 		break;
1899 	default:
1900 		break;
1901 	}
1902 
1903 	transport_lun_remove_cmd(cmd);
1904 	transport_cmd_check_stop_to_fabric(cmd);
1905 	return;
1906 
1907 queue_full:
1908 	pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
1909 		" data_direction: %d\n", cmd, cmd->data_direction);
1910 	cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1911 	transport_handle_queue_full(cmd, cmd->se_dev);
1912 }
1913 
1914 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
1915 {
1916 	struct scatterlist *sg;
1917 	int count;
1918 
1919 	for_each_sg(sgl, sg, nents, count)
1920 		__free_page(sg_page(sg));
1921 
1922 	kfree(sgl);
1923 }
1924 
1925 static inline void transport_free_pages(struct se_cmd *cmd)
1926 {
1927 	if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
1928 		return;
1929 
1930 	transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
1931 	cmd->t_data_sg = NULL;
1932 	cmd->t_data_nents = 0;
1933 
1934 	transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
1935 	cmd->t_bidi_data_sg = NULL;
1936 	cmd->t_bidi_data_nents = 0;
1937 }
1938 
1939 /**
1940  * transport_release_cmd - free a command
1941  * @cmd:       command to free
1942  *
1943  * This routine unconditionally frees a command, and reference counting
1944  * or list removal must be done in the caller.
1945  */
1946 static void transport_release_cmd(struct se_cmd *cmd)
1947 {
1948 	BUG_ON(!cmd->se_tfo);
1949 
1950 	if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1951 		core_tmr_release_req(cmd->se_tmr_req);
1952 	if (cmd->t_task_cdb != cmd->__t_task_cdb)
1953 		kfree(cmd->t_task_cdb);
1954 	/*
1955 	 * If this cmd has been setup with target_get_sess_cmd(), drop
1956 	 * the kref and call ->release_cmd() in kref callback.
1957 	 */
1958 	 if (cmd->check_release != 0) {
1959 		target_put_sess_cmd(cmd->se_sess, cmd);
1960 		return;
1961 	}
1962 	cmd->se_tfo->release_cmd(cmd);
1963 }
1964 
1965 /**
1966  * transport_put_cmd - release a reference to a command
1967  * @cmd:       command to release
1968  *
1969  * This routine releases our reference to the command and frees it if possible.
1970  */
1971 static void transport_put_cmd(struct se_cmd *cmd)
1972 {
1973 	unsigned long flags;
1974 
1975 	spin_lock_irqsave(&cmd->t_state_lock, flags);
1976 	if (atomic_read(&cmd->t_fe_count) &&
1977 	    !atomic_dec_and_test(&cmd->t_fe_count)) {
1978 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1979 		return;
1980 	}
1981 
1982 	if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
1983 		cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
1984 		target_remove_from_state_list(cmd);
1985 	}
1986 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1987 
1988 	transport_free_pages(cmd);
1989 	transport_release_cmd(cmd);
1990 	return;
1991 }
1992 
1993 void *transport_kmap_data_sg(struct se_cmd *cmd)
1994 {
1995 	struct scatterlist *sg = cmd->t_data_sg;
1996 	struct page **pages;
1997 	int i;
1998 
1999 	/*
2000 	 * We need to take into account a possible offset here for fabrics like
2001 	 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2002 	 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2003 	 */
2004 	if (!cmd->t_data_nents)
2005 		return NULL;
2006 
2007 	BUG_ON(!sg);
2008 	if (cmd->t_data_nents == 1)
2009 		return kmap(sg_page(sg)) + sg->offset;
2010 
2011 	/* >1 page. use vmap */
2012 	pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2013 	if (!pages)
2014 		return NULL;
2015 
2016 	/* convert sg[] to pages[] */
2017 	for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2018 		pages[i] = sg_page(sg);
2019 	}
2020 
2021 	cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2022 	kfree(pages);
2023 	if (!cmd->t_data_vmap)
2024 		return NULL;
2025 
2026 	return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2027 }
2028 EXPORT_SYMBOL(transport_kmap_data_sg);
2029 
2030 void transport_kunmap_data_sg(struct se_cmd *cmd)
2031 {
2032 	if (!cmd->t_data_nents) {
2033 		return;
2034 	} else if (cmd->t_data_nents == 1) {
2035 		kunmap(sg_page(cmd->t_data_sg));
2036 		return;
2037 	}
2038 
2039 	vunmap(cmd->t_data_vmap);
2040 	cmd->t_data_vmap = NULL;
2041 }
2042 EXPORT_SYMBOL(transport_kunmap_data_sg);
2043 
2044 static int
2045 transport_generic_get_mem(struct se_cmd *cmd)
2046 {
2047 	u32 length = cmd->data_length;
2048 	unsigned int nents;
2049 	struct page *page;
2050 	gfp_t zero_flag;
2051 	int i = 0;
2052 
2053 	nents = DIV_ROUND_UP(length, PAGE_SIZE);
2054 	cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
2055 	if (!cmd->t_data_sg)
2056 		return -ENOMEM;
2057 
2058 	cmd->t_data_nents = nents;
2059 	sg_init_table(cmd->t_data_sg, nents);
2060 
2061 	zero_flag = cmd->se_cmd_flags & SCF_SCSI_DATA_CDB ? 0 : __GFP_ZERO;
2062 
2063 	while (length) {
2064 		u32 page_len = min_t(u32, length, PAGE_SIZE);
2065 		page = alloc_page(GFP_KERNEL | zero_flag);
2066 		if (!page)
2067 			goto out;
2068 
2069 		sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
2070 		length -= page_len;
2071 		i++;
2072 	}
2073 	return 0;
2074 
2075 out:
2076 	while (i > 0) {
2077 		i--;
2078 		__free_page(sg_page(&cmd->t_data_sg[i]));
2079 	}
2080 	kfree(cmd->t_data_sg);
2081 	cmd->t_data_sg = NULL;
2082 	return -ENOMEM;
2083 }
2084 
2085 /*
2086  * Allocate any required resources to execute the command.  For writes we
2087  * might not have the payload yet, so notify the fabric via a call to
2088  * ->write_pending instead. Otherwise place it on the execution queue.
2089  */
2090 sense_reason_t
2091 transport_generic_new_cmd(struct se_cmd *cmd)
2092 {
2093 	int ret = 0;
2094 
2095 	/*
2096 	 * Determine is the TCM fabric module has already allocated physical
2097 	 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2098 	 * beforehand.
2099 	 */
2100 	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2101 	    cmd->data_length) {
2102 		ret = transport_generic_get_mem(cmd);
2103 		if (ret < 0)
2104 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2105 	}
2106 
2107 	atomic_inc(&cmd->t_fe_count);
2108 
2109 	/*
2110 	 * If this command is not a write we can execute it right here,
2111 	 * for write buffers we need to notify the fabric driver first
2112 	 * and let it call back once the write buffers are ready.
2113 	 */
2114 	target_add_to_state_list(cmd);
2115 	if (cmd->data_direction != DMA_TO_DEVICE) {
2116 		target_execute_cmd(cmd);
2117 		return 0;
2118 	}
2119 
2120 	spin_lock_irq(&cmd->t_state_lock);
2121 	cmd->t_state = TRANSPORT_WRITE_PENDING;
2122 	spin_unlock_irq(&cmd->t_state_lock);
2123 
2124 	transport_cmd_check_stop(cmd, false);
2125 
2126 	ret = cmd->se_tfo->write_pending(cmd);
2127 	if (ret == -EAGAIN || ret == -ENOMEM)
2128 		goto queue_full;
2129 
2130 	/* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2131 	WARN_ON(ret);
2132 
2133 	return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2134 
2135 queue_full:
2136 	pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2137 	cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2138 	transport_handle_queue_full(cmd, cmd->se_dev);
2139 	return 0;
2140 }
2141 EXPORT_SYMBOL(transport_generic_new_cmd);
2142 
2143 static void transport_write_pending_qf(struct se_cmd *cmd)
2144 {
2145 	int ret;
2146 
2147 	ret = cmd->se_tfo->write_pending(cmd);
2148 	if (ret == -EAGAIN || ret == -ENOMEM) {
2149 		pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2150 			 cmd);
2151 		transport_handle_queue_full(cmd, cmd->se_dev);
2152 	}
2153 }
2154 
2155 void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2156 {
2157 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2158 		if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2159 			 transport_wait_for_tasks(cmd);
2160 
2161 		transport_release_cmd(cmd);
2162 	} else {
2163 		if (wait_for_tasks)
2164 			transport_wait_for_tasks(cmd);
2165 
2166 		if (cmd->se_lun)
2167 			transport_lun_remove_cmd(cmd);
2168 
2169 		transport_put_cmd(cmd);
2170 	}
2171 }
2172 EXPORT_SYMBOL(transport_generic_free_cmd);
2173 
2174 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2175  * @se_sess:	session to reference
2176  * @se_cmd:	command descriptor to add
2177  * @ack_kref:	Signal that fabric will perform an ack target_put_sess_cmd()
2178  */
2179 int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2180 			       bool ack_kref)
2181 {
2182 	unsigned long flags;
2183 	int ret = 0;
2184 
2185 	kref_init(&se_cmd->cmd_kref);
2186 	/*
2187 	 * Add a second kref if the fabric caller is expecting to handle
2188 	 * fabric acknowledgement that requires two target_put_sess_cmd()
2189 	 * invocations before se_cmd descriptor release.
2190 	 */
2191 	if (ack_kref == true) {
2192 		kref_get(&se_cmd->cmd_kref);
2193 		se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2194 	}
2195 
2196 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2197 	if (se_sess->sess_tearing_down) {
2198 		ret = -ESHUTDOWN;
2199 		goto out;
2200 	}
2201 	list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2202 	se_cmd->check_release = 1;
2203 
2204 out:
2205 	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2206 	return ret;
2207 }
2208 EXPORT_SYMBOL(target_get_sess_cmd);
2209 
2210 static void target_release_cmd_kref(struct kref *kref)
2211 {
2212 	struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2213 	struct se_session *se_sess = se_cmd->se_sess;
2214 
2215 	if (list_empty(&se_cmd->se_cmd_list)) {
2216 		spin_unlock(&se_sess->sess_cmd_lock);
2217 		se_cmd->se_tfo->release_cmd(se_cmd);
2218 		return;
2219 	}
2220 	if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2221 		spin_unlock(&se_sess->sess_cmd_lock);
2222 		complete(&se_cmd->cmd_wait_comp);
2223 		return;
2224 	}
2225 	list_del(&se_cmd->se_cmd_list);
2226 	spin_unlock(&se_sess->sess_cmd_lock);
2227 
2228 	se_cmd->se_tfo->release_cmd(se_cmd);
2229 }
2230 
2231 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2232  * @se_sess:	session to reference
2233  * @se_cmd:	command descriptor to drop
2234  */
2235 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2236 {
2237 	return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2238 			&se_sess->sess_cmd_lock);
2239 }
2240 EXPORT_SYMBOL(target_put_sess_cmd);
2241 
2242 /* target_sess_cmd_list_set_waiting - Flag all commands in
2243  *         sess_cmd_list to complete cmd_wait_comp.  Set
2244  *         sess_tearing_down so no more commands are queued.
2245  * @se_sess:	session to flag
2246  */
2247 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2248 {
2249 	struct se_cmd *se_cmd;
2250 	unsigned long flags;
2251 
2252 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2253 
2254 	WARN_ON(se_sess->sess_tearing_down);
2255 	se_sess->sess_tearing_down = 1;
2256 
2257 	list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list)
2258 		se_cmd->cmd_wait_set = 1;
2259 
2260 	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2261 }
2262 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2263 
2264 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2265  * @se_sess:    session to wait for active I/O
2266  * @wait_for_tasks:	Make extra transport_wait_for_tasks call
2267  */
2268 void target_wait_for_sess_cmds(
2269 	struct se_session *se_sess,
2270 	int wait_for_tasks)
2271 {
2272 	struct se_cmd *se_cmd, *tmp_cmd;
2273 	bool rc = false;
2274 
2275 	list_for_each_entry_safe(se_cmd, tmp_cmd,
2276 				&se_sess->sess_cmd_list, se_cmd_list) {
2277 		list_del(&se_cmd->se_cmd_list);
2278 
2279 		pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2280 			" %d\n", se_cmd, se_cmd->t_state,
2281 			se_cmd->se_tfo->get_cmd_state(se_cmd));
2282 
2283 		if (wait_for_tasks) {
2284 			pr_debug("Calling transport_wait_for_tasks se_cmd: %p t_state: %d,"
2285 				" fabric state: %d\n", se_cmd, se_cmd->t_state,
2286 				se_cmd->se_tfo->get_cmd_state(se_cmd));
2287 
2288 			rc = transport_wait_for_tasks(se_cmd);
2289 
2290 			pr_debug("After transport_wait_for_tasks se_cmd: %p t_state: %d,"
2291 				" fabric state: %d\n", se_cmd, se_cmd->t_state,
2292 				se_cmd->se_tfo->get_cmd_state(se_cmd));
2293 		}
2294 
2295 		if (!rc) {
2296 			wait_for_completion(&se_cmd->cmd_wait_comp);
2297 			pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2298 				" fabric state: %d\n", se_cmd, se_cmd->t_state,
2299 				se_cmd->se_tfo->get_cmd_state(se_cmd));
2300 		}
2301 
2302 		se_cmd->se_tfo->release_cmd(se_cmd);
2303 	}
2304 }
2305 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2306 
2307 /*	transport_lun_wait_for_tasks():
2308  *
2309  *	Called from ConfigFS context to stop the passed struct se_cmd to allow
2310  *	an struct se_lun to be successfully shutdown.
2311  */
2312 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
2313 {
2314 	unsigned long flags;
2315 	int ret = 0;
2316 
2317 	/*
2318 	 * If the frontend has already requested this struct se_cmd to
2319 	 * be stopped, we can safely ignore this struct se_cmd.
2320 	 */
2321 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2322 	if (cmd->transport_state & CMD_T_STOP) {
2323 		cmd->transport_state &= ~CMD_T_LUN_STOP;
2324 
2325 		pr_debug("ConfigFS ITT[0x%08x] - CMD_T_STOP, skipping\n",
2326 			 cmd->se_tfo->get_task_tag(cmd));
2327 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2328 		transport_cmd_check_stop(cmd, false);
2329 		return -EPERM;
2330 	}
2331 	cmd->transport_state |= CMD_T_LUN_FE_STOP;
2332 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2333 
2334 	// XXX: audit task_flags checks.
2335 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2336 	if ((cmd->transport_state & CMD_T_BUSY) &&
2337 	    (cmd->transport_state & CMD_T_SENT)) {
2338 		if (!target_stop_cmd(cmd, &flags))
2339 			ret++;
2340 	}
2341 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2342 
2343 	pr_debug("ConfigFS: cmd: %p stop tasks ret:"
2344 			" %d\n", cmd, ret);
2345 	if (!ret) {
2346 		pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
2347 				cmd->se_tfo->get_task_tag(cmd));
2348 		wait_for_completion(&cmd->transport_lun_stop_comp);
2349 		pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
2350 				cmd->se_tfo->get_task_tag(cmd));
2351 	}
2352 
2353 	return 0;
2354 }
2355 
2356 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
2357 {
2358 	struct se_cmd *cmd = NULL;
2359 	unsigned long lun_flags, cmd_flags;
2360 	/*
2361 	 * Do exception processing and return CHECK_CONDITION status to the
2362 	 * Initiator Port.
2363 	 */
2364 	spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2365 	while (!list_empty(&lun->lun_cmd_list)) {
2366 		cmd = list_first_entry(&lun->lun_cmd_list,
2367 		       struct se_cmd, se_lun_node);
2368 		list_del_init(&cmd->se_lun_node);
2369 
2370 		spin_lock(&cmd->t_state_lock);
2371 		pr_debug("SE_LUN[%d] - Setting cmd->transport"
2372 			"_lun_stop for  ITT: 0x%08x\n",
2373 			cmd->se_lun->unpacked_lun,
2374 			cmd->se_tfo->get_task_tag(cmd));
2375 		cmd->transport_state |= CMD_T_LUN_STOP;
2376 		spin_unlock(&cmd->t_state_lock);
2377 
2378 		spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2379 
2380 		if (!cmd->se_lun) {
2381 			pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
2382 				cmd->se_tfo->get_task_tag(cmd),
2383 				cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2384 			BUG();
2385 		}
2386 		/*
2387 		 * If the Storage engine still owns the iscsi_cmd_t, determine
2388 		 * and/or stop its context.
2389 		 */
2390 		pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
2391 			"_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
2392 			cmd->se_tfo->get_task_tag(cmd));
2393 
2394 		if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
2395 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2396 			continue;
2397 		}
2398 
2399 		pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
2400 			"_wait_for_tasks(): SUCCESS\n",
2401 			cmd->se_lun->unpacked_lun,
2402 			cmd->se_tfo->get_task_tag(cmd));
2403 
2404 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2405 		if (!(cmd->transport_state & CMD_T_DEV_ACTIVE)) {
2406 			spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2407 			goto check_cond;
2408 		}
2409 		cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
2410 		target_remove_from_state_list(cmd);
2411 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2412 
2413 		/*
2414 		 * The Storage engine stopped this struct se_cmd before it was
2415 		 * send to the fabric frontend for delivery back to the
2416 		 * Initiator Node.  Return this SCSI CDB back with an
2417 		 * CHECK_CONDITION status.
2418 		 */
2419 check_cond:
2420 		transport_send_check_condition_and_sense(cmd,
2421 				TCM_NON_EXISTENT_LUN, 0);
2422 		/*
2423 		 *  If the fabric frontend is waiting for this iscsi_cmd_t to
2424 		 * be released, notify the waiting thread now that LU has
2425 		 * finished accessing it.
2426 		 */
2427 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2428 		if (cmd->transport_state & CMD_T_LUN_FE_STOP) {
2429 			pr_debug("SE_LUN[%d] - Detected FE stop for"
2430 				" struct se_cmd: %p ITT: 0x%08x\n",
2431 				lun->unpacked_lun,
2432 				cmd, cmd->se_tfo->get_task_tag(cmd));
2433 
2434 			spin_unlock_irqrestore(&cmd->t_state_lock,
2435 					cmd_flags);
2436 			transport_cmd_check_stop(cmd, false);
2437 			complete(&cmd->transport_lun_fe_stop_comp);
2438 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2439 			continue;
2440 		}
2441 		pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
2442 			lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
2443 
2444 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2445 		spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2446 	}
2447 	spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2448 }
2449 
2450 static int transport_clear_lun_thread(void *p)
2451 {
2452 	struct se_lun *lun = p;
2453 
2454 	__transport_clear_lun_from_sessions(lun);
2455 	complete(&lun->lun_shutdown_comp);
2456 
2457 	return 0;
2458 }
2459 
2460 int transport_clear_lun_from_sessions(struct se_lun *lun)
2461 {
2462 	struct task_struct *kt;
2463 
2464 	kt = kthread_run(transport_clear_lun_thread, lun,
2465 			"tcm_cl_%u", lun->unpacked_lun);
2466 	if (IS_ERR(kt)) {
2467 		pr_err("Unable to start clear_lun thread\n");
2468 		return PTR_ERR(kt);
2469 	}
2470 	wait_for_completion(&lun->lun_shutdown_comp);
2471 
2472 	return 0;
2473 }
2474 
2475 /**
2476  * transport_wait_for_tasks - wait for completion to occur
2477  * @cmd:	command to wait
2478  *
2479  * Called from frontend fabric context to wait for storage engine
2480  * to pause and/or release frontend generated struct se_cmd.
2481  */
2482 bool transport_wait_for_tasks(struct se_cmd *cmd)
2483 {
2484 	unsigned long flags;
2485 
2486 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2487 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2488 	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2489 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2490 		return false;
2491 	}
2492 
2493 	if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2494 	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2495 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2496 		return false;
2497 	}
2498 	/*
2499 	 * If we are already stopped due to an external event (ie: LUN shutdown)
2500 	 * sleep until the connection can have the passed struct se_cmd back.
2501 	 * The cmd->transport_lun_stopped_sem will be upped by
2502 	 * transport_clear_lun_from_sessions() once the ConfigFS context caller
2503 	 * has completed its operation on the struct se_cmd.
2504 	 */
2505 	if (cmd->transport_state & CMD_T_LUN_STOP) {
2506 		pr_debug("wait_for_tasks: Stopping"
2507 			" wait_for_completion(&cmd->t_tasktransport_lun_fe"
2508 			"_stop_comp); for ITT: 0x%08x\n",
2509 			cmd->se_tfo->get_task_tag(cmd));
2510 		/*
2511 		 * There is a special case for WRITES where a FE exception +
2512 		 * LUN shutdown means ConfigFS context is still sleeping on
2513 		 * transport_lun_stop_comp in transport_lun_wait_for_tasks().
2514 		 * We go ahead and up transport_lun_stop_comp just to be sure
2515 		 * here.
2516 		 */
2517 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2518 		complete(&cmd->transport_lun_stop_comp);
2519 		wait_for_completion(&cmd->transport_lun_fe_stop_comp);
2520 		spin_lock_irqsave(&cmd->t_state_lock, flags);
2521 
2522 		target_remove_from_state_list(cmd);
2523 		/*
2524 		 * At this point, the frontend who was the originator of this
2525 		 * struct se_cmd, now owns the structure and can be released through
2526 		 * normal means below.
2527 		 */
2528 		pr_debug("wait_for_tasks: Stopped"
2529 			" wait_for_completion(&cmd->t_tasktransport_lun_fe_"
2530 			"stop_comp); for ITT: 0x%08x\n",
2531 			cmd->se_tfo->get_task_tag(cmd));
2532 
2533 		cmd->transport_state &= ~CMD_T_LUN_STOP;
2534 	}
2535 
2536 	if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2537 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2538 		return false;
2539 	}
2540 
2541 	cmd->transport_state |= CMD_T_STOP;
2542 
2543 	pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2544 		" i_state: %d, t_state: %d, CMD_T_STOP\n",
2545 		cmd, cmd->se_tfo->get_task_tag(cmd),
2546 		cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2547 
2548 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2549 
2550 	wait_for_completion(&cmd->t_transport_stop_comp);
2551 
2552 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2553 	cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2554 
2555 	pr_debug("wait_for_tasks: Stopped wait_for_completion("
2556 		"&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2557 		cmd->se_tfo->get_task_tag(cmd));
2558 
2559 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2560 
2561 	return true;
2562 }
2563 EXPORT_SYMBOL(transport_wait_for_tasks);
2564 
2565 static int transport_get_sense_codes(
2566 	struct se_cmd *cmd,
2567 	u8 *asc,
2568 	u8 *ascq)
2569 {
2570 	*asc = cmd->scsi_asc;
2571 	*ascq = cmd->scsi_ascq;
2572 
2573 	return 0;
2574 }
2575 
2576 int
2577 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2578 		sense_reason_t reason, int from_transport)
2579 {
2580 	unsigned char *buffer = cmd->sense_buffer;
2581 	unsigned long flags;
2582 	u8 asc = 0, ascq = 0;
2583 
2584 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2585 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2586 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2587 		return 0;
2588 	}
2589 	cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2590 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2591 
2592 	if (!reason && from_transport)
2593 		goto after_reason;
2594 
2595 	if (!from_transport)
2596 		cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2597 
2598 	/*
2599 	 * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2600 	 * SENSE KEY values from include/scsi/scsi.h
2601 	 */
2602 	switch (reason) {
2603 	case TCM_NO_SENSE:
2604 		/* CURRENT ERROR */
2605 		buffer[0] = 0x70;
2606 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2607 		/* Not Ready */
2608 		buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2609 		/* NO ADDITIONAL SENSE INFORMATION */
2610 		buffer[SPC_ASC_KEY_OFFSET] = 0;
2611 		buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2612 		break;
2613 	case TCM_NON_EXISTENT_LUN:
2614 		/* CURRENT ERROR */
2615 		buffer[0] = 0x70;
2616 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2617 		/* ILLEGAL REQUEST */
2618 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2619 		/* LOGICAL UNIT NOT SUPPORTED */
2620 		buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2621 		break;
2622 	case TCM_UNSUPPORTED_SCSI_OPCODE:
2623 	case TCM_SECTOR_COUNT_TOO_MANY:
2624 		/* CURRENT ERROR */
2625 		buffer[0] = 0x70;
2626 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2627 		/* ILLEGAL REQUEST */
2628 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2629 		/* INVALID COMMAND OPERATION CODE */
2630 		buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2631 		break;
2632 	case TCM_UNKNOWN_MODE_PAGE:
2633 		/* CURRENT ERROR */
2634 		buffer[0] = 0x70;
2635 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2636 		/* ILLEGAL REQUEST */
2637 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2638 		/* INVALID FIELD IN CDB */
2639 		buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2640 		break;
2641 	case TCM_CHECK_CONDITION_ABORT_CMD:
2642 		/* CURRENT ERROR */
2643 		buffer[0] = 0x70;
2644 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2645 		/* ABORTED COMMAND */
2646 		buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2647 		/* BUS DEVICE RESET FUNCTION OCCURRED */
2648 		buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2649 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2650 		break;
2651 	case TCM_INCORRECT_AMOUNT_OF_DATA:
2652 		/* CURRENT ERROR */
2653 		buffer[0] = 0x70;
2654 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2655 		/* ABORTED COMMAND */
2656 		buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2657 		/* WRITE ERROR */
2658 		buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2659 		/* NOT ENOUGH UNSOLICITED DATA */
2660 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2661 		break;
2662 	case TCM_INVALID_CDB_FIELD:
2663 		/* CURRENT ERROR */
2664 		buffer[0] = 0x70;
2665 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2666 		/* ILLEGAL REQUEST */
2667 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2668 		/* INVALID FIELD IN CDB */
2669 		buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2670 		break;
2671 	case TCM_INVALID_PARAMETER_LIST:
2672 		/* CURRENT ERROR */
2673 		buffer[0] = 0x70;
2674 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2675 		/* ILLEGAL REQUEST */
2676 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2677 		/* INVALID FIELD IN PARAMETER LIST */
2678 		buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2679 		break;
2680 	case TCM_PARAMETER_LIST_LENGTH_ERROR:
2681 		/* CURRENT ERROR */
2682 		buffer[0] = 0x70;
2683 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2684 		/* ILLEGAL REQUEST */
2685 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2686 		/* PARAMETER LIST LENGTH ERROR */
2687 		buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2688 		break;
2689 	case TCM_UNEXPECTED_UNSOLICITED_DATA:
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 		/* WRITE ERROR */
2696 		buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2697 		/* UNEXPECTED_UNSOLICITED_DATA */
2698 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2699 		break;
2700 	case TCM_SERVICE_CRC_ERROR:
2701 		/* CURRENT ERROR */
2702 		buffer[0] = 0x70;
2703 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2704 		/* ABORTED COMMAND */
2705 		buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2706 		/* PROTOCOL SERVICE CRC ERROR */
2707 		buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2708 		/* N/A */
2709 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2710 		break;
2711 	case TCM_SNACK_REJECTED:
2712 		/* CURRENT ERROR */
2713 		buffer[0] = 0x70;
2714 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2715 		/* ABORTED COMMAND */
2716 		buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2717 		/* READ ERROR */
2718 		buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2719 		/* FAILED RETRANSMISSION REQUEST */
2720 		buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2721 		break;
2722 	case TCM_WRITE_PROTECTED:
2723 		/* CURRENT ERROR */
2724 		buffer[0] = 0x70;
2725 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2726 		/* DATA PROTECT */
2727 		buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2728 		/* WRITE PROTECTED */
2729 		buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2730 		break;
2731 	case TCM_ADDRESS_OUT_OF_RANGE:
2732 		/* CURRENT ERROR */
2733 		buffer[0] = 0x70;
2734 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2735 		/* ILLEGAL REQUEST */
2736 		buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2737 		/* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2738 		buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2739 		break;
2740 	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2741 		/* CURRENT ERROR */
2742 		buffer[0] = 0x70;
2743 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2744 		/* UNIT ATTENTION */
2745 		buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2746 		core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2747 		buffer[SPC_ASC_KEY_OFFSET] = asc;
2748 		buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2749 		break;
2750 	case TCM_CHECK_CONDITION_NOT_READY:
2751 		/* CURRENT ERROR */
2752 		buffer[0] = 0x70;
2753 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2754 		/* Not Ready */
2755 		buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2756 		transport_get_sense_codes(cmd, &asc, &ascq);
2757 		buffer[SPC_ASC_KEY_OFFSET] = asc;
2758 		buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2759 		break;
2760 	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2761 	default:
2762 		/* CURRENT ERROR */
2763 		buffer[0] = 0x70;
2764 		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2765 		/*
2766 		 * Returning ILLEGAL REQUEST would cause immediate IO errors on
2767 		 * Solaris initiators.  Returning NOT READY instead means the
2768 		 * operations will be retried a finite number of times and we
2769 		 * can survive intermittent errors.
2770 		 */
2771 		buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2772 		/* LOGICAL UNIT COMMUNICATION FAILURE */
2773 		buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2774 		break;
2775 	}
2776 	/*
2777 	 * This code uses linux/include/scsi/scsi.h SAM status codes!
2778 	 */
2779 	cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2780 	/*
2781 	 * Automatically padded, this value is encoded in the fabric's
2782 	 * data_length response PDU containing the SCSI defined sense data.
2783 	 */
2784 	cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2785 
2786 after_reason:
2787 	return cmd->se_tfo->queue_status(cmd);
2788 }
2789 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2790 
2791 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2792 {
2793 	if (!(cmd->transport_state & CMD_T_ABORTED))
2794 		return 0;
2795 
2796 	if (!send_status || (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
2797 		return 1;
2798 
2799 	pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2800 		 cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2801 
2802 	cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
2803 	cmd->se_tfo->queue_status(cmd);
2804 
2805 	return 1;
2806 }
2807 EXPORT_SYMBOL(transport_check_aborted_status);
2808 
2809 void transport_send_task_abort(struct se_cmd *cmd)
2810 {
2811 	unsigned long flags;
2812 
2813 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2814 	if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION | SCF_SENT_DELAYED_TAS)) {
2815 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2816 		return;
2817 	}
2818 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2819 
2820 	/*
2821 	 * If there are still expected incoming fabric WRITEs, we wait
2822 	 * until until they have completed before sending a TASK_ABORTED
2823 	 * response.  This response with TASK_ABORTED status will be
2824 	 * queued back to fabric module by transport_check_aborted_status().
2825 	 */
2826 	if (cmd->data_direction == DMA_TO_DEVICE) {
2827 		if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2828 			cmd->transport_state |= CMD_T_ABORTED;
2829 			smp_mb__after_atomic_inc();
2830 		}
2831 	}
2832 	cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2833 
2834 	transport_lun_remove_cmd(cmd);
2835 
2836 	pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2837 		" ITT: 0x%08x\n", cmd->t_task_cdb[0],
2838 		cmd->se_tfo->get_task_tag(cmd));
2839 
2840 	cmd->se_tfo->queue_status(cmd);
2841 }
2842 
2843 static void target_tmr_work(struct work_struct *work)
2844 {
2845 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2846 	struct se_device *dev = cmd->se_dev;
2847 	struct se_tmr_req *tmr = cmd->se_tmr_req;
2848 	int ret;
2849 
2850 	switch (tmr->function) {
2851 	case TMR_ABORT_TASK:
2852 		core_tmr_abort_task(dev, tmr, cmd->se_sess);
2853 		break;
2854 	case TMR_ABORT_TASK_SET:
2855 	case TMR_CLEAR_ACA:
2856 	case TMR_CLEAR_TASK_SET:
2857 		tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2858 		break;
2859 	case TMR_LUN_RESET:
2860 		ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2861 		tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2862 					 TMR_FUNCTION_REJECTED;
2863 		break;
2864 	case TMR_TARGET_WARM_RESET:
2865 		tmr->response = TMR_FUNCTION_REJECTED;
2866 		break;
2867 	case TMR_TARGET_COLD_RESET:
2868 		tmr->response = TMR_FUNCTION_REJECTED;
2869 		break;
2870 	default:
2871 		pr_err("Uknown TMR function: 0x%02x.\n",
2872 				tmr->function);
2873 		tmr->response = TMR_FUNCTION_REJECTED;
2874 		break;
2875 	}
2876 
2877 	cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2878 	cmd->se_tfo->queue_tm_rsp(cmd);
2879 
2880 	transport_cmd_check_stop_to_fabric(cmd);
2881 }
2882 
2883 int transport_generic_handle_tmr(
2884 	struct se_cmd *cmd)
2885 {
2886 	INIT_WORK(&cmd->work, target_tmr_work);
2887 	queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2888 	return 0;
2889 }
2890 EXPORT_SYMBOL(transport_generic_handle_tmr);
2891