1 /*******************************************************************************
2  * Filename:  target_core_transport.c
3  *
4  * This file contains the Generic Target Engine Core.
5  *
6  * Copyright (c) 2002, 2003, 2004, 2005 PyX Technologies, Inc.
7  * Copyright (c) 2005, 2006, 2007 SBE, Inc.
8  * Copyright (c) 2007-2010 Rising Tide Systems
9  * Copyright (c) 2008-2010 Linux-iSCSI.org
10  *
11  * Nicholas A. Bellinger <nab@kernel.org>
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26  *
27  ******************************************************************************/
28 
29 #include <linux/version.h>
30 #include <linux/net.h>
31 #include <linux/delay.h>
32 #include <linux/string.h>
33 #include <linux/timer.h>
34 #include <linux/slab.h>
35 #include <linux/blkdev.h>
36 #include <linux/spinlock.h>
37 #include <linux/kthread.h>
38 #include <linux/in.h>
39 #include <linux/cdrom.h>
40 #include <asm/unaligned.h>
41 #include <net/sock.h>
42 #include <net/tcp.h>
43 #include <scsi/scsi.h>
44 #include <scsi/scsi_cmnd.h>
45 #include <scsi/scsi_tcq.h>
46 
47 #include <target/target_core_base.h>
48 #include <target/target_core_device.h>
49 #include <target/target_core_tmr.h>
50 #include <target/target_core_tpg.h>
51 #include <target/target_core_transport.h>
52 #include <target/target_core_fabric_ops.h>
53 #include <target/target_core_configfs.h>
54 
55 #include "target_core_alua.h"
56 #include "target_core_hba.h"
57 #include "target_core_pr.h"
58 #include "target_core_scdb.h"
59 #include "target_core_ua.h"
60 
61 static int sub_api_initialized;
62 
63 static struct kmem_cache *se_cmd_cache;
64 static struct kmem_cache *se_sess_cache;
65 struct kmem_cache *se_tmr_req_cache;
66 struct kmem_cache *se_ua_cache;
67 struct kmem_cache *t10_pr_reg_cache;
68 struct kmem_cache *t10_alua_lu_gp_cache;
69 struct kmem_cache *t10_alua_lu_gp_mem_cache;
70 struct kmem_cache *t10_alua_tg_pt_gp_cache;
71 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
72 
73 /* Used for transport_dev_get_map_*() */
74 typedef int (*map_func_t)(struct se_task *, u32);
75 
76 static int transport_generic_write_pending(struct se_cmd *);
77 static int transport_processing_thread(void *param);
78 static int __transport_execute_tasks(struct se_device *dev);
79 static void transport_complete_task_attr(struct se_cmd *cmd);
80 static int transport_complete_qf(struct se_cmd *cmd);
81 static void transport_handle_queue_full(struct se_cmd *cmd,
82 		struct se_device *dev, int (*qf_callback)(struct se_cmd *));
83 static void transport_direct_request_timeout(struct se_cmd *cmd);
84 static void transport_free_dev_tasks(struct se_cmd *cmd);
85 static u32 transport_allocate_tasks(struct se_cmd *cmd,
86 		unsigned long long starting_lba,
87 		enum dma_data_direction data_direction,
88 		struct scatterlist *sgl, unsigned int nents);
89 static int transport_generic_get_mem(struct se_cmd *cmd);
90 static int transport_generic_remove(struct se_cmd *cmd,
91 		int session_reinstatement);
92 static void transport_release_fe_cmd(struct se_cmd *cmd);
93 static void transport_remove_cmd_from_queue(struct se_cmd *cmd,
94 		struct se_queue_obj *qobj);
95 static int transport_set_sense_codes(struct se_cmd *cmd, u8 asc, u8 ascq);
96 static void transport_stop_all_task_timers(struct se_cmd *cmd);
97 
98 int init_se_kmem_caches(void)
99 {
100 	se_cmd_cache = kmem_cache_create("se_cmd_cache",
101 			sizeof(struct se_cmd), __alignof__(struct se_cmd), 0, NULL);
102 	if (!se_cmd_cache) {
103 		pr_err("kmem_cache_create for struct se_cmd failed\n");
104 		goto out;
105 	}
106 	se_tmr_req_cache = kmem_cache_create("se_tmr_cache",
107 			sizeof(struct se_tmr_req), __alignof__(struct se_tmr_req),
108 			0, NULL);
109 	if (!se_tmr_req_cache) {
110 		pr_err("kmem_cache_create() for struct se_tmr_req"
111 				" failed\n");
112 		goto out;
113 	}
114 	se_sess_cache = kmem_cache_create("se_sess_cache",
115 			sizeof(struct se_session), __alignof__(struct se_session),
116 			0, NULL);
117 	if (!se_sess_cache) {
118 		pr_err("kmem_cache_create() for struct se_session"
119 				" failed\n");
120 		goto out;
121 	}
122 	se_ua_cache = kmem_cache_create("se_ua_cache",
123 			sizeof(struct se_ua), __alignof__(struct se_ua),
124 			0, NULL);
125 	if (!se_ua_cache) {
126 		pr_err("kmem_cache_create() for struct se_ua failed\n");
127 		goto out;
128 	}
129 	t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
130 			sizeof(struct t10_pr_registration),
131 			__alignof__(struct t10_pr_registration), 0, NULL);
132 	if (!t10_pr_reg_cache) {
133 		pr_err("kmem_cache_create() for struct t10_pr_registration"
134 				" failed\n");
135 		goto out;
136 	}
137 	t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
138 			sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
139 			0, NULL);
140 	if (!t10_alua_lu_gp_cache) {
141 		pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
142 				" failed\n");
143 		goto out;
144 	}
145 	t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
146 			sizeof(struct t10_alua_lu_gp_member),
147 			__alignof__(struct t10_alua_lu_gp_member), 0, NULL);
148 	if (!t10_alua_lu_gp_mem_cache) {
149 		pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
150 				"cache failed\n");
151 		goto out;
152 	}
153 	t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
154 			sizeof(struct t10_alua_tg_pt_gp),
155 			__alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
156 	if (!t10_alua_tg_pt_gp_cache) {
157 		pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
158 				"cache failed\n");
159 		goto out;
160 	}
161 	t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
162 			"t10_alua_tg_pt_gp_mem_cache",
163 			sizeof(struct t10_alua_tg_pt_gp_member),
164 			__alignof__(struct t10_alua_tg_pt_gp_member),
165 			0, NULL);
166 	if (!t10_alua_tg_pt_gp_mem_cache) {
167 		pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
168 				"mem_t failed\n");
169 		goto out;
170 	}
171 
172 	return 0;
173 out:
174 	if (se_cmd_cache)
175 		kmem_cache_destroy(se_cmd_cache);
176 	if (se_tmr_req_cache)
177 		kmem_cache_destroy(se_tmr_req_cache);
178 	if (se_sess_cache)
179 		kmem_cache_destroy(se_sess_cache);
180 	if (se_ua_cache)
181 		kmem_cache_destroy(se_ua_cache);
182 	if (t10_pr_reg_cache)
183 		kmem_cache_destroy(t10_pr_reg_cache);
184 	if (t10_alua_lu_gp_cache)
185 		kmem_cache_destroy(t10_alua_lu_gp_cache);
186 	if (t10_alua_lu_gp_mem_cache)
187 		kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
188 	if (t10_alua_tg_pt_gp_cache)
189 		kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
190 	if (t10_alua_tg_pt_gp_mem_cache)
191 		kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
192 	return -ENOMEM;
193 }
194 
195 void release_se_kmem_caches(void)
196 {
197 	kmem_cache_destroy(se_cmd_cache);
198 	kmem_cache_destroy(se_tmr_req_cache);
199 	kmem_cache_destroy(se_sess_cache);
200 	kmem_cache_destroy(se_ua_cache);
201 	kmem_cache_destroy(t10_pr_reg_cache);
202 	kmem_cache_destroy(t10_alua_lu_gp_cache);
203 	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
204 	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
205 	kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
206 }
207 
208 /* This code ensures unique mib indexes are handed out. */
209 static DEFINE_SPINLOCK(scsi_mib_index_lock);
210 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
211 
212 /*
213  * Allocate a new row index for the entry type specified
214  */
215 u32 scsi_get_new_index(scsi_index_t type)
216 {
217 	u32 new_index;
218 
219 	BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
220 
221 	spin_lock(&scsi_mib_index_lock);
222 	new_index = ++scsi_mib_index[type];
223 	spin_unlock(&scsi_mib_index_lock);
224 
225 	return new_index;
226 }
227 
228 void transport_init_queue_obj(struct se_queue_obj *qobj)
229 {
230 	atomic_set(&qobj->queue_cnt, 0);
231 	INIT_LIST_HEAD(&qobj->qobj_list);
232 	init_waitqueue_head(&qobj->thread_wq);
233 	spin_lock_init(&qobj->cmd_queue_lock);
234 }
235 EXPORT_SYMBOL(transport_init_queue_obj);
236 
237 static int transport_subsystem_reqmods(void)
238 {
239 	int ret;
240 
241 	ret = request_module("target_core_iblock");
242 	if (ret != 0)
243 		pr_err("Unable to load target_core_iblock\n");
244 
245 	ret = request_module("target_core_file");
246 	if (ret != 0)
247 		pr_err("Unable to load target_core_file\n");
248 
249 	ret = request_module("target_core_pscsi");
250 	if (ret != 0)
251 		pr_err("Unable to load target_core_pscsi\n");
252 
253 	ret = request_module("target_core_stgt");
254 	if (ret != 0)
255 		pr_err("Unable to load target_core_stgt\n");
256 
257 	return 0;
258 }
259 
260 int transport_subsystem_check_init(void)
261 {
262 	int ret;
263 
264 	if (sub_api_initialized)
265 		return 0;
266 	/*
267 	 * Request the loading of known TCM subsystem plugins..
268 	 */
269 	ret = transport_subsystem_reqmods();
270 	if (ret < 0)
271 		return ret;
272 
273 	sub_api_initialized = 1;
274 	return 0;
275 }
276 
277 struct se_session *transport_init_session(void)
278 {
279 	struct se_session *se_sess;
280 
281 	se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
282 	if (!se_sess) {
283 		pr_err("Unable to allocate struct se_session from"
284 				" se_sess_cache\n");
285 		return ERR_PTR(-ENOMEM);
286 	}
287 	INIT_LIST_HEAD(&se_sess->sess_list);
288 	INIT_LIST_HEAD(&se_sess->sess_acl_list);
289 
290 	return se_sess;
291 }
292 EXPORT_SYMBOL(transport_init_session);
293 
294 /*
295  * Called with spin_lock_bh(&struct se_portal_group->session_lock called.
296  */
297 void __transport_register_session(
298 	struct se_portal_group *se_tpg,
299 	struct se_node_acl *se_nacl,
300 	struct se_session *se_sess,
301 	void *fabric_sess_ptr)
302 {
303 	unsigned char buf[PR_REG_ISID_LEN];
304 
305 	se_sess->se_tpg = se_tpg;
306 	se_sess->fabric_sess_ptr = fabric_sess_ptr;
307 	/*
308 	 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
309 	 *
310 	 * Only set for struct se_session's that will actually be moving I/O.
311 	 * eg: *NOT* discovery sessions.
312 	 */
313 	if (se_nacl) {
314 		/*
315 		 * If the fabric module supports an ISID based TransportID,
316 		 * save this value in binary from the fabric I_T Nexus now.
317 		 */
318 		if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
319 			memset(&buf[0], 0, PR_REG_ISID_LEN);
320 			se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
321 					&buf[0], PR_REG_ISID_LEN);
322 			se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
323 		}
324 		spin_lock_irq(&se_nacl->nacl_sess_lock);
325 		/*
326 		 * The se_nacl->nacl_sess pointer will be set to the
327 		 * last active I_T Nexus for each struct se_node_acl.
328 		 */
329 		se_nacl->nacl_sess = se_sess;
330 
331 		list_add_tail(&se_sess->sess_acl_list,
332 			      &se_nacl->acl_sess_list);
333 		spin_unlock_irq(&se_nacl->nacl_sess_lock);
334 	}
335 	list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
336 
337 	pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
338 		se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
339 }
340 EXPORT_SYMBOL(__transport_register_session);
341 
342 void transport_register_session(
343 	struct se_portal_group *se_tpg,
344 	struct se_node_acl *se_nacl,
345 	struct se_session *se_sess,
346 	void *fabric_sess_ptr)
347 {
348 	spin_lock_bh(&se_tpg->session_lock);
349 	__transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
350 	spin_unlock_bh(&se_tpg->session_lock);
351 }
352 EXPORT_SYMBOL(transport_register_session);
353 
354 void transport_deregister_session_configfs(struct se_session *se_sess)
355 {
356 	struct se_node_acl *se_nacl;
357 	unsigned long flags;
358 	/*
359 	 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
360 	 */
361 	se_nacl = se_sess->se_node_acl;
362 	if (se_nacl) {
363 		spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
364 		list_del(&se_sess->sess_acl_list);
365 		/*
366 		 * If the session list is empty, then clear the pointer.
367 		 * Otherwise, set the struct se_session pointer from the tail
368 		 * element of the per struct se_node_acl active session list.
369 		 */
370 		if (list_empty(&se_nacl->acl_sess_list))
371 			se_nacl->nacl_sess = NULL;
372 		else {
373 			se_nacl->nacl_sess = container_of(
374 					se_nacl->acl_sess_list.prev,
375 					struct se_session, sess_acl_list);
376 		}
377 		spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
378 	}
379 }
380 EXPORT_SYMBOL(transport_deregister_session_configfs);
381 
382 void transport_free_session(struct se_session *se_sess)
383 {
384 	kmem_cache_free(se_sess_cache, se_sess);
385 }
386 EXPORT_SYMBOL(transport_free_session);
387 
388 void transport_deregister_session(struct se_session *se_sess)
389 {
390 	struct se_portal_group *se_tpg = se_sess->se_tpg;
391 	struct se_node_acl *se_nacl;
392 
393 	if (!se_tpg) {
394 		transport_free_session(se_sess);
395 		return;
396 	}
397 
398 	spin_lock_bh(&se_tpg->session_lock);
399 	list_del(&se_sess->sess_list);
400 	se_sess->se_tpg = NULL;
401 	se_sess->fabric_sess_ptr = NULL;
402 	spin_unlock_bh(&se_tpg->session_lock);
403 
404 	/*
405 	 * Determine if we need to do extra work for this initiator node's
406 	 * struct se_node_acl if it had been previously dynamically generated.
407 	 */
408 	se_nacl = se_sess->se_node_acl;
409 	if (se_nacl) {
410 		spin_lock_bh(&se_tpg->acl_node_lock);
411 		if (se_nacl->dynamic_node_acl) {
412 			if (!se_tpg->se_tpg_tfo->tpg_check_demo_mode_cache(
413 					se_tpg)) {
414 				list_del(&se_nacl->acl_list);
415 				se_tpg->num_node_acls--;
416 				spin_unlock_bh(&se_tpg->acl_node_lock);
417 
418 				core_tpg_wait_for_nacl_pr_ref(se_nacl);
419 				core_free_device_list_for_node(se_nacl, se_tpg);
420 				se_tpg->se_tpg_tfo->tpg_release_fabric_acl(se_tpg,
421 						se_nacl);
422 				spin_lock_bh(&se_tpg->acl_node_lock);
423 			}
424 		}
425 		spin_unlock_bh(&se_tpg->acl_node_lock);
426 	}
427 
428 	transport_free_session(se_sess);
429 
430 	pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
431 		se_tpg->se_tpg_tfo->get_fabric_name());
432 }
433 EXPORT_SYMBOL(transport_deregister_session);
434 
435 /*
436  * Called with cmd->t_state_lock held.
437  */
438 static void transport_all_task_dev_remove_state(struct se_cmd *cmd)
439 {
440 	struct se_device *dev;
441 	struct se_task *task;
442 	unsigned long flags;
443 
444 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
445 		dev = task->se_dev;
446 		if (!dev)
447 			continue;
448 
449 		if (atomic_read(&task->task_active))
450 			continue;
451 
452 		if (!atomic_read(&task->task_state_active))
453 			continue;
454 
455 		spin_lock_irqsave(&dev->execute_task_lock, flags);
456 		list_del(&task->t_state_list);
457 		pr_debug("Removed ITT: 0x%08x dev: %p task[%p]\n",
458 			cmd->se_tfo->get_task_tag(cmd), dev, task);
459 		spin_unlock_irqrestore(&dev->execute_task_lock, flags);
460 
461 		atomic_set(&task->task_state_active, 0);
462 		atomic_dec(&cmd->t_task_cdbs_ex_left);
463 	}
464 }
465 
466 /*	transport_cmd_check_stop():
467  *
468  *	'transport_off = 1' determines if t_transport_active should be cleared.
469  *	'transport_off = 2' determines if task_dev_state should be removed.
470  *
471  *	A non-zero u8 t_state sets cmd->t_state.
472  *	Returns 1 when command is stopped, else 0.
473  */
474 static int transport_cmd_check_stop(
475 	struct se_cmd *cmd,
476 	int transport_off,
477 	u8 t_state)
478 {
479 	unsigned long flags;
480 
481 	spin_lock_irqsave(&cmd->t_state_lock, flags);
482 	/*
483 	 * Determine if IOCTL context caller in requesting the stopping of this
484 	 * command for LUN shutdown purposes.
485 	 */
486 	if (atomic_read(&cmd->transport_lun_stop)) {
487 		pr_debug("%s:%d atomic_read(&cmd->transport_lun_stop)"
488 			" == TRUE for ITT: 0x%08x\n", __func__, __LINE__,
489 			cmd->se_tfo->get_task_tag(cmd));
490 
491 		cmd->deferred_t_state = cmd->t_state;
492 		cmd->t_state = TRANSPORT_DEFERRED_CMD;
493 		atomic_set(&cmd->t_transport_active, 0);
494 		if (transport_off == 2)
495 			transport_all_task_dev_remove_state(cmd);
496 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
497 
498 		complete(&cmd->transport_lun_stop_comp);
499 		return 1;
500 	}
501 	/*
502 	 * Determine if frontend context caller is requesting the stopping of
503 	 * this command for frontend exceptions.
504 	 */
505 	if (atomic_read(&cmd->t_transport_stop)) {
506 		pr_debug("%s:%d atomic_read(&cmd->t_transport_stop) =="
507 			" TRUE for ITT: 0x%08x\n", __func__, __LINE__,
508 			cmd->se_tfo->get_task_tag(cmd));
509 
510 		cmd->deferred_t_state = cmd->t_state;
511 		cmd->t_state = TRANSPORT_DEFERRED_CMD;
512 		if (transport_off == 2)
513 			transport_all_task_dev_remove_state(cmd);
514 
515 		/*
516 		 * Clear struct se_cmd->se_lun before the transport_off == 2 handoff
517 		 * to FE.
518 		 */
519 		if (transport_off == 2)
520 			cmd->se_lun = NULL;
521 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
522 
523 		complete(&cmd->t_transport_stop_comp);
524 		return 1;
525 	}
526 	if (transport_off) {
527 		atomic_set(&cmd->t_transport_active, 0);
528 		if (transport_off == 2) {
529 			transport_all_task_dev_remove_state(cmd);
530 			/*
531 			 * Clear struct se_cmd->se_lun before the transport_off == 2
532 			 * handoff to fabric module.
533 			 */
534 			cmd->se_lun = NULL;
535 			/*
536 			 * Some fabric modules like tcm_loop can release
537 			 * their internally allocated I/O reference now and
538 			 * struct se_cmd now.
539 			 */
540 			if (cmd->se_tfo->check_stop_free != NULL) {
541 				spin_unlock_irqrestore(
542 					&cmd->t_state_lock, flags);
543 
544 				cmd->se_tfo->check_stop_free(cmd);
545 				return 1;
546 			}
547 		}
548 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
549 
550 		return 0;
551 	} else if (t_state)
552 		cmd->t_state = t_state;
553 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
554 
555 	return 0;
556 }
557 
558 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
559 {
560 	return transport_cmd_check_stop(cmd, 2, 0);
561 }
562 
563 static void transport_lun_remove_cmd(struct se_cmd *cmd)
564 {
565 	struct se_lun *lun = cmd->se_lun;
566 	unsigned long flags;
567 
568 	if (!lun)
569 		return;
570 
571 	spin_lock_irqsave(&cmd->t_state_lock, flags);
572 	if (!atomic_read(&cmd->transport_dev_active)) {
573 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
574 		goto check_lun;
575 	}
576 	atomic_set(&cmd->transport_dev_active, 0);
577 	transport_all_task_dev_remove_state(cmd);
578 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
579 
580 
581 check_lun:
582 	spin_lock_irqsave(&lun->lun_cmd_lock, flags);
583 	if (atomic_read(&cmd->transport_lun_active)) {
584 		list_del(&cmd->se_lun_node);
585 		atomic_set(&cmd->transport_lun_active, 0);
586 #if 0
587 		pr_debug("Removed ITT: 0x%08x from LUN LIST[%d]\n"
588 			cmd->se_tfo->get_task_tag(cmd), lun->unpacked_lun);
589 #endif
590 	}
591 	spin_unlock_irqrestore(&lun->lun_cmd_lock, flags);
592 }
593 
594 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
595 {
596 	transport_remove_cmd_from_queue(cmd, &cmd->se_dev->dev_queue_obj);
597 	transport_lun_remove_cmd(cmd);
598 
599 	if (transport_cmd_check_stop_to_fabric(cmd))
600 		return;
601 	if (remove)
602 		transport_generic_remove(cmd, 0);
603 }
604 
605 void transport_cmd_finish_abort_tmr(struct se_cmd *cmd)
606 {
607 	transport_remove_cmd_from_queue(cmd, &cmd->se_dev->dev_queue_obj);
608 
609 	if (transport_cmd_check_stop_to_fabric(cmd))
610 		return;
611 
612 	transport_generic_remove(cmd, 0);
613 }
614 
615 static void transport_add_cmd_to_queue(
616 	struct se_cmd *cmd,
617 	int t_state)
618 {
619 	struct se_device *dev = cmd->se_dev;
620 	struct se_queue_obj *qobj = &dev->dev_queue_obj;
621 	unsigned long flags;
622 
623 	INIT_LIST_HEAD(&cmd->se_queue_node);
624 
625 	if (t_state) {
626 		spin_lock_irqsave(&cmd->t_state_lock, flags);
627 		cmd->t_state = t_state;
628 		atomic_set(&cmd->t_transport_active, 1);
629 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
630 	}
631 
632 	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
633 	if (cmd->se_cmd_flags & SCF_EMULATE_QUEUE_FULL) {
634 		cmd->se_cmd_flags &= ~SCF_EMULATE_QUEUE_FULL;
635 		list_add(&cmd->se_queue_node, &qobj->qobj_list);
636 	} else
637 		list_add_tail(&cmd->se_queue_node, &qobj->qobj_list);
638 	atomic_inc(&cmd->t_transport_queue_active);
639 	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
640 
641 	atomic_inc(&qobj->queue_cnt);
642 	wake_up_interruptible(&qobj->thread_wq);
643 }
644 
645 static struct se_cmd *
646 transport_get_cmd_from_queue(struct se_queue_obj *qobj)
647 {
648 	struct se_cmd *cmd;
649 	unsigned long flags;
650 
651 	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
652 	if (list_empty(&qobj->qobj_list)) {
653 		spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
654 		return NULL;
655 	}
656 	cmd = list_first_entry(&qobj->qobj_list, struct se_cmd, se_queue_node);
657 
658 	atomic_dec(&cmd->t_transport_queue_active);
659 
660 	list_del(&cmd->se_queue_node);
661 	atomic_dec(&qobj->queue_cnt);
662 	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
663 
664 	return cmd;
665 }
666 
667 static void transport_remove_cmd_from_queue(struct se_cmd *cmd,
668 		struct se_queue_obj *qobj)
669 {
670 	struct se_cmd *t;
671 	unsigned long flags;
672 
673 	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
674 	if (!atomic_read(&cmd->t_transport_queue_active)) {
675 		spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
676 		return;
677 	}
678 
679 	list_for_each_entry(t, &qobj->qobj_list, se_queue_node)
680 		if (t == cmd) {
681 			atomic_dec(&cmd->t_transport_queue_active);
682 			atomic_dec(&qobj->queue_cnt);
683 			list_del(&cmd->se_queue_node);
684 			break;
685 		}
686 	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
687 
688 	if (atomic_read(&cmd->t_transport_queue_active)) {
689 		pr_err("ITT: 0x%08x t_transport_queue_active: %d\n",
690 			cmd->se_tfo->get_task_tag(cmd),
691 			atomic_read(&cmd->t_transport_queue_active));
692 	}
693 }
694 
695 /*
696  * Completion function used by TCM subsystem plugins (such as FILEIO)
697  * for queueing up response from struct se_subsystem_api->do_task()
698  */
699 void transport_complete_sync_cache(struct se_cmd *cmd, int good)
700 {
701 	struct se_task *task = list_entry(cmd->t_task_list.next,
702 				struct se_task, t_list);
703 
704 	if (good) {
705 		cmd->scsi_status = SAM_STAT_GOOD;
706 		task->task_scsi_status = GOOD;
707 	} else {
708 		task->task_scsi_status = SAM_STAT_CHECK_CONDITION;
709 		task->task_error_status = PYX_TRANSPORT_ILLEGAL_REQUEST;
710 		task->task_se_cmd->transport_error_status =
711 					PYX_TRANSPORT_ILLEGAL_REQUEST;
712 	}
713 
714 	transport_complete_task(task, good);
715 }
716 EXPORT_SYMBOL(transport_complete_sync_cache);
717 
718 /*	transport_complete_task():
719  *
720  *	Called from interrupt and non interrupt context depending
721  *	on the transport plugin.
722  */
723 void transport_complete_task(struct se_task *task, int success)
724 {
725 	struct se_cmd *cmd = task->task_se_cmd;
726 	struct se_device *dev = task->se_dev;
727 	int t_state;
728 	unsigned long flags;
729 #if 0
730 	pr_debug("task: %p CDB: 0x%02x obj_ptr: %p\n", task,
731 			cmd->t_task_cdb[0], dev);
732 #endif
733 	if (dev)
734 		atomic_inc(&dev->depth_left);
735 
736 	spin_lock_irqsave(&cmd->t_state_lock, flags);
737 	atomic_set(&task->task_active, 0);
738 
739 	/*
740 	 * See if any sense data exists, if so set the TASK_SENSE flag.
741 	 * Also check for any other post completion work that needs to be
742 	 * done by the plugins.
743 	 */
744 	if (dev && dev->transport->transport_complete) {
745 		if (dev->transport->transport_complete(task) != 0) {
746 			cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
747 			task->task_sense = 1;
748 			success = 1;
749 		}
750 	}
751 
752 	/*
753 	 * See if we are waiting for outstanding struct se_task
754 	 * to complete for an exception condition
755 	 */
756 	if (atomic_read(&task->task_stop)) {
757 		/*
758 		 * Decrement cmd->t_se_count if this task had
759 		 * previously thrown its timeout exception handler.
760 		 */
761 		if (atomic_read(&task->task_timeout)) {
762 			atomic_dec(&cmd->t_se_count);
763 			atomic_set(&task->task_timeout, 0);
764 		}
765 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
766 
767 		complete(&task->task_stop_comp);
768 		return;
769 	}
770 	/*
771 	 * If the task's timeout handler has fired, use the t_task_cdbs_timeout
772 	 * left counter to determine when the struct se_cmd is ready to be queued to
773 	 * the processing thread.
774 	 */
775 	if (atomic_read(&task->task_timeout)) {
776 		if (!atomic_dec_and_test(
777 				&cmd->t_task_cdbs_timeout_left)) {
778 			spin_unlock_irqrestore(&cmd->t_state_lock,
779 				flags);
780 			return;
781 		}
782 		t_state = TRANSPORT_COMPLETE_TIMEOUT;
783 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
784 
785 		transport_add_cmd_to_queue(cmd, t_state);
786 		return;
787 	}
788 	atomic_dec(&cmd->t_task_cdbs_timeout_left);
789 
790 	/*
791 	 * Decrement the outstanding t_task_cdbs_left count.  The last
792 	 * struct se_task from struct se_cmd will complete itself into the
793 	 * device queue depending upon int success.
794 	 */
795 	if (!atomic_dec_and_test(&cmd->t_task_cdbs_left)) {
796 		if (!success)
797 			cmd->t_tasks_failed = 1;
798 
799 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
800 		return;
801 	}
802 
803 	if (!success || cmd->t_tasks_failed) {
804 		t_state = TRANSPORT_COMPLETE_FAILURE;
805 		if (!task->task_error_status) {
806 			task->task_error_status =
807 				PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
808 			cmd->transport_error_status =
809 				PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
810 		}
811 	} else {
812 		atomic_set(&cmd->t_transport_complete, 1);
813 		t_state = TRANSPORT_COMPLETE_OK;
814 	}
815 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
816 
817 	transport_add_cmd_to_queue(cmd, t_state);
818 }
819 EXPORT_SYMBOL(transport_complete_task);
820 
821 /*
822  * Called by transport_add_tasks_from_cmd() once a struct se_cmd's
823  * struct se_task list are ready to be added to the active execution list
824  * struct se_device
825 
826  * Called with se_dev_t->execute_task_lock called.
827  */
828 static inline int transport_add_task_check_sam_attr(
829 	struct se_task *task,
830 	struct se_task *task_prev,
831 	struct se_device *dev)
832 {
833 	/*
834 	 * No SAM Task attribute emulation enabled, add to tail of
835 	 * execution queue
836 	 */
837 	if (dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED) {
838 		list_add_tail(&task->t_execute_list, &dev->execute_task_list);
839 		return 0;
840 	}
841 	/*
842 	 * HEAD_OF_QUEUE attribute for received CDB, which means
843 	 * the first task that is associated with a struct se_cmd goes to
844 	 * head of the struct se_device->execute_task_list, and task_prev
845 	 * after that for each subsequent task
846 	 */
847 	if (task->task_se_cmd->sam_task_attr == MSG_HEAD_TAG) {
848 		list_add(&task->t_execute_list,
849 				(task_prev != NULL) ?
850 				&task_prev->t_execute_list :
851 				&dev->execute_task_list);
852 
853 		pr_debug("Set HEAD_OF_QUEUE for task CDB: 0x%02x"
854 				" in execution queue\n",
855 				task->task_se_cmd->t_task_cdb[0]);
856 		return 1;
857 	}
858 	/*
859 	 * For ORDERED, SIMPLE or UNTAGGED attribute tasks once they have been
860 	 * transitioned from Dermant -> Active state, and are added to the end
861 	 * of the struct se_device->execute_task_list
862 	 */
863 	list_add_tail(&task->t_execute_list, &dev->execute_task_list);
864 	return 0;
865 }
866 
867 /*	__transport_add_task_to_execute_queue():
868  *
869  *	Called with se_dev_t->execute_task_lock called.
870  */
871 static void __transport_add_task_to_execute_queue(
872 	struct se_task *task,
873 	struct se_task *task_prev,
874 	struct se_device *dev)
875 {
876 	int head_of_queue;
877 
878 	head_of_queue = transport_add_task_check_sam_attr(task, task_prev, dev);
879 	atomic_inc(&dev->execute_tasks);
880 
881 	if (atomic_read(&task->task_state_active))
882 		return;
883 	/*
884 	 * Determine if this task needs to go to HEAD_OF_QUEUE for the
885 	 * state list as well.  Running with SAM Task Attribute emulation
886 	 * will always return head_of_queue == 0 here
887 	 */
888 	if (head_of_queue)
889 		list_add(&task->t_state_list, (task_prev) ?
890 				&task_prev->t_state_list :
891 				&dev->state_task_list);
892 	else
893 		list_add_tail(&task->t_state_list, &dev->state_task_list);
894 
895 	atomic_set(&task->task_state_active, 1);
896 
897 	pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n",
898 		task->task_se_cmd->se_tfo->get_task_tag(task->task_se_cmd),
899 		task, dev);
900 }
901 
902 static void transport_add_tasks_to_state_queue(struct se_cmd *cmd)
903 {
904 	struct se_device *dev;
905 	struct se_task *task;
906 	unsigned long flags;
907 
908 	spin_lock_irqsave(&cmd->t_state_lock, flags);
909 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
910 		dev = task->se_dev;
911 
912 		if (atomic_read(&task->task_state_active))
913 			continue;
914 
915 		spin_lock(&dev->execute_task_lock);
916 		list_add_tail(&task->t_state_list, &dev->state_task_list);
917 		atomic_set(&task->task_state_active, 1);
918 
919 		pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n",
920 			task->task_se_cmd->se_tfo->get_task_tag(
921 			task->task_se_cmd), task, dev);
922 
923 		spin_unlock(&dev->execute_task_lock);
924 	}
925 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
926 }
927 
928 static void transport_add_tasks_from_cmd(struct se_cmd *cmd)
929 {
930 	struct se_device *dev = cmd->se_dev;
931 	struct se_task *task, *task_prev = NULL;
932 	unsigned long flags;
933 
934 	spin_lock_irqsave(&dev->execute_task_lock, flags);
935 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
936 		if (atomic_read(&task->task_execute_queue))
937 			continue;
938 		/*
939 		 * __transport_add_task_to_execute_queue() handles the
940 		 * SAM Task Attribute emulation if enabled
941 		 */
942 		__transport_add_task_to_execute_queue(task, task_prev, dev);
943 		atomic_set(&task->task_execute_queue, 1);
944 		task_prev = task;
945 	}
946 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
947 }
948 
949 /*	transport_remove_task_from_execute_queue():
950  *
951  *
952  */
953 void transport_remove_task_from_execute_queue(
954 	struct se_task *task,
955 	struct se_device *dev)
956 {
957 	unsigned long flags;
958 
959 	if (atomic_read(&task->task_execute_queue) == 0) {
960 		dump_stack();
961 		return;
962 	}
963 
964 	spin_lock_irqsave(&dev->execute_task_lock, flags);
965 	list_del(&task->t_execute_list);
966 	atomic_set(&task->task_execute_queue, 0);
967 	atomic_dec(&dev->execute_tasks);
968 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
969 }
970 
971 /*
972  * Handle QUEUE_FULL / -EAGAIN status
973  */
974 
975 static void target_qf_do_work(struct work_struct *work)
976 {
977 	struct se_device *dev = container_of(work, struct se_device,
978 					qf_work_queue);
979 	struct se_cmd *cmd, *cmd_tmp;
980 
981 	spin_lock_irq(&dev->qf_cmd_lock);
982 	list_for_each_entry_safe(cmd, cmd_tmp, &dev->qf_cmd_list, se_qf_node) {
983 
984 		list_del(&cmd->se_qf_node);
985 		atomic_dec(&dev->dev_qf_count);
986 		smp_mb__after_atomic_dec();
987 		spin_unlock_irq(&dev->qf_cmd_lock);
988 
989 		pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
990 			" context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
991 			(cmd->t_state == TRANSPORT_COMPLETE_OK) ? "COMPLETE_OK" :
992 			(cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
993 			: "UNKNOWN");
994 		/*
995 		 * The SCF_EMULATE_QUEUE_FULL flag will be cleared once se_cmd
996 		 * has been added to head of queue
997 		 */
998 		transport_add_cmd_to_queue(cmd, cmd->t_state);
999 
1000 		spin_lock_irq(&dev->qf_cmd_lock);
1001 	}
1002 	spin_unlock_irq(&dev->qf_cmd_lock);
1003 }
1004 
1005 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
1006 {
1007 	switch (cmd->data_direction) {
1008 	case DMA_NONE:
1009 		return "NONE";
1010 	case DMA_FROM_DEVICE:
1011 		return "READ";
1012 	case DMA_TO_DEVICE:
1013 		return "WRITE";
1014 	case DMA_BIDIRECTIONAL:
1015 		return "BIDI";
1016 	default:
1017 		break;
1018 	}
1019 
1020 	return "UNKNOWN";
1021 }
1022 
1023 void transport_dump_dev_state(
1024 	struct se_device *dev,
1025 	char *b,
1026 	int *bl)
1027 {
1028 	*bl += sprintf(b + *bl, "Status: ");
1029 	switch (dev->dev_status) {
1030 	case TRANSPORT_DEVICE_ACTIVATED:
1031 		*bl += sprintf(b + *bl, "ACTIVATED");
1032 		break;
1033 	case TRANSPORT_DEVICE_DEACTIVATED:
1034 		*bl += sprintf(b + *bl, "DEACTIVATED");
1035 		break;
1036 	case TRANSPORT_DEVICE_SHUTDOWN:
1037 		*bl += sprintf(b + *bl, "SHUTDOWN");
1038 		break;
1039 	case TRANSPORT_DEVICE_OFFLINE_ACTIVATED:
1040 	case TRANSPORT_DEVICE_OFFLINE_DEACTIVATED:
1041 		*bl += sprintf(b + *bl, "OFFLINE");
1042 		break;
1043 	default:
1044 		*bl += sprintf(b + *bl, "UNKNOWN=%d", dev->dev_status);
1045 		break;
1046 	}
1047 
1048 	*bl += sprintf(b + *bl, "  Execute/Left/Max Queue Depth: %d/%d/%d",
1049 		atomic_read(&dev->execute_tasks), atomic_read(&dev->depth_left),
1050 		dev->queue_depth);
1051 	*bl += sprintf(b + *bl, "  SectorSize: %u  MaxSectors: %u\n",
1052 		dev->se_sub_dev->se_dev_attrib.block_size, dev->se_sub_dev->se_dev_attrib.max_sectors);
1053 	*bl += sprintf(b + *bl, "        ");
1054 }
1055 
1056 /*	transport_release_all_cmds():
1057  *
1058  *
1059  */
1060 static void transport_release_all_cmds(struct se_device *dev)
1061 {
1062 	struct se_cmd *cmd, *tcmd;
1063 	int bug_out = 0, t_state;
1064 	unsigned long flags;
1065 
1066 	spin_lock_irqsave(&dev->dev_queue_obj.cmd_queue_lock, flags);
1067 	list_for_each_entry_safe(cmd, tcmd, &dev->dev_queue_obj.qobj_list,
1068 				se_queue_node) {
1069 		t_state = cmd->t_state;
1070 		list_del(&cmd->se_queue_node);
1071 		spin_unlock_irqrestore(&dev->dev_queue_obj.cmd_queue_lock,
1072 				flags);
1073 
1074 		pr_err("Releasing ITT: 0x%08x, i_state: %u,"
1075 			" t_state: %u directly\n",
1076 			cmd->se_tfo->get_task_tag(cmd),
1077 			cmd->se_tfo->get_cmd_state(cmd), t_state);
1078 
1079 		transport_release_fe_cmd(cmd);
1080 		bug_out = 1;
1081 
1082 		spin_lock_irqsave(&dev->dev_queue_obj.cmd_queue_lock, flags);
1083 	}
1084 	spin_unlock_irqrestore(&dev->dev_queue_obj.cmd_queue_lock, flags);
1085 #if 0
1086 	if (bug_out)
1087 		BUG();
1088 #endif
1089 }
1090 
1091 void transport_dump_vpd_proto_id(
1092 	struct t10_vpd *vpd,
1093 	unsigned char *p_buf,
1094 	int p_buf_len)
1095 {
1096 	unsigned char buf[VPD_TMP_BUF_SIZE];
1097 	int len;
1098 
1099 	memset(buf, 0, VPD_TMP_BUF_SIZE);
1100 	len = sprintf(buf, "T10 VPD Protocol Identifier: ");
1101 
1102 	switch (vpd->protocol_identifier) {
1103 	case 0x00:
1104 		sprintf(buf+len, "Fibre Channel\n");
1105 		break;
1106 	case 0x10:
1107 		sprintf(buf+len, "Parallel SCSI\n");
1108 		break;
1109 	case 0x20:
1110 		sprintf(buf+len, "SSA\n");
1111 		break;
1112 	case 0x30:
1113 		sprintf(buf+len, "IEEE 1394\n");
1114 		break;
1115 	case 0x40:
1116 		sprintf(buf+len, "SCSI Remote Direct Memory Access"
1117 				" Protocol\n");
1118 		break;
1119 	case 0x50:
1120 		sprintf(buf+len, "Internet SCSI (iSCSI)\n");
1121 		break;
1122 	case 0x60:
1123 		sprintf(buf+len, "SAS Serial SCSI Protocol\n");
1124 		break;
1125 	case 0x70:
1126 		sprintf(buf+len, "Automation/Drive Interface Transport"
1127 				" Protocol\n");
1128 		break;
1129 	case 0x80:
1130 		sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
1131 		break;
1132 	default:
1133 		sprintf(buf+len, "Unknown 0x%02x\n",
1134 				vpd->protocol_identifier);
1135 		break;
1136 	}
1137 
1138 	if (p_buf)
1139 		strncpy(p_buf, buf, p_buf_len);
1140 	else
1141 		pr_debug("%s", buf);
1142 }
1143 
1144 void
1145 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1146 {
1147 	/*
1148 	 * Check if the Protocol Identifier Valid (PIV) bit is set..
1149 	 *
1150 	 * from spc3r23.pdf section 7.5.1
1151 	 */
1152 	 if (page_83[1] & 0x80) {
1153 		vpd->protocol_identifier = (page_83[0] & 0xf0);
1154 		vpd->protocol_identifier_set = 1;
1155 		transport_dump_vpd_proto_id(vpd, NULL, 0);
1156 	}
1157 }
1158 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1159 
1160 int transport_dump_vpd_assoc(
1161 	struct t10_vpd *vpd,
1162 	unsigned char *p_buf,
1163 	int p_buf_len)
1164 {
1165 	unsigned char buf[VPD_TMP_BUF_SIZE];
1166 	int ret = 0;
1167 	int len;
1168 
1169 	memset(buf, 0, VPD_TMP_BUF_SIZE);
1170 	len = sprintf(buf, "T10 VPD Identifier Association: ");
1171 
1172 	switch (vpd->association) {
1173 	case 0x00:
1174 		sprintf(buf+len, "addressed logical unit\n");
1175 		break;
1176 	case 0x10:
1177 		sprintf(buf+len, "target port\n");
1178 		break;
1179 	case 0x20:
1180 		sprintf(buf+len, "SCSI target device\n");
1181 		break;
1182 	default:
1183 		sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1184 		ret = -EINVAL;
1185 		break;
1186 	}
1187 
1188 	if (p_buf)
1189 		strncpy(p_buf, buf, p_buf_len);
1190 	else
1191 		pr_debug("%s", buf);
1192 
1193 	return ret;
1194 }
1195 
1196 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1197 {
1198 	/*
1199 	 * The VPD identification association..
1200 	 *
1201 	 * from spc3r23.pdf Section 7.6.3.1 Table 297
1202 	 */
1203 	vpd->association = (page_83[1] & 0x30);
1204 	return transport_dump_vpd_assoc(vpd, NULL, 0);
1205 }
1206 EXPORT_SYMBOL(transport_set_vpd_assoc);
1207 
1208 int transport_dump_vpd_ident_type(
1209 	struct t10_vpd *vpd,
1210 	unsigned char *p_buf,
1211 	int p_buf_len)
1212 {
1213 	unsigned char buf[VPD_TMP_BUF_SIZE];
1214 	int ret = 0;
1215 	int len;
1216 
1217 	memset(buf, 0, VPD_TMP_BUF_SIZE);
1218 	len = sprintf(buf, "T10 VPD Identifier Type: ");
1219 
1220 	switch (vpd->device_identifier_type) {
1221 	case 0x00:
1222 		sprintf(buf+len, "Vendor specific\n");
1223 		break;
1224 	case 0x01:
1225 		sprintf(buf+len, "T10 Vendor ID based\n");
1226 		break;
1227 	case 0x02:
1228 		sprintf(buf+len, "EUI-64 based\n");
1229 		break;
1230 	case 0x03:
1231 		sprintf(buf+len, "NAA\n");
1232 		break;
1233 	case 0x04:
1234 		sprintf(buf+len, "Relative target port identifier\n");
1235 		break;
1236 	case 0x08:
1237 		sprintf(buf+len, "SCSI name string\n");
1238 		break;
1239 	default:
1240 		sprintf(buf+len, "Unsupported: 0x%02x\n",
1241 				vpd->device_identifier_type);
1242 		ret = -EINVAL;
1243 		break;
1244 	}
1245 
1246 	if (p_buf) {
1247 		if (p_buf_len < strlen(buf)+1)
1248 			return -EINVAL;
1249 		strncpy(p_buf, buf, p_buf_len);
1250 	} else {
1251 		pr_debug("%s", buf);
1252 	}
1253 
1254 	return ret;
1255 }
1256 
1257 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1258 {
1259 	/*
1260 	 * The VPD identifier type..
1261 	 *
1262 	 * from spc3r23.pdf Section 7.6.3.1 Table 298
1263 	 */
1264 	vpd->device_identifier_type = (page_83[1] & 0x0f);
1265 	return transport_dump_vpd_ident_type(vpd, NULL, 0);
1266 }
1267 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1268 
1269 int transport_dump_vpd_ident(
1270 	struct t10_vpd *vpd,
1271 	unsigned char *p_buf,
1272 	int p_buf_len)
1273 {
1274 	unsigned char buf[VPD_TMP_BUF_SIZE];
1275 	int ret = 0;
1276 
1277 	memset(buf, 0, VPD_TMP_BUF_SIZE);
1278 
1279 	switch (vpd->device_identifier_code_set) {
1280 	case 0x01: /* Binary */
1281 		sprintf(buf, "T10 VPD Binary Device Identifier: %s\n",
1282 			&vpd->device_identifier[0]);
1283 		break;
1284 	case 0x02: /* ASCII */
1285 		sprintf(buf, "T10 VPD ASCII Device Identifier: %s\n",
1286 			&vpd->device_identifier[0]);
1287 		break;
1288 	case 0x03: /* UTF-8 */
1289 		sprintf(buf, "T10 VPD UTF-8 Device Identifier: %s\n",
1290 			&vpd->device_identifier[0]);
1291 		break;
1292 	default:
1293 		sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1294 			" 0x%02x", vpd->device_identifier_code_set);
1295 		ret = -EINVAL;
1296 		break;
1297 	}
1298 
1299 	if (p_buf)
1300 		strncpy(p_buf, buf, p_buf_len);
1301 	else
1302 		pr_debug("%s", buf);
1303 
1304 	return ret;
1305 }
1306 
1307 int
1308 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1309 {
1310 	static const char hex_str[] = "0123456789abcdef";
1311 	int j = 0, i = 4; /* offset to start of the identifer */
1312 
1313 	/*
1314 	 * The VPD Code Set (encoding)
1315 	 *
1316 	 * from spc3r23.pdf Section 7.6.3.1 Table 296
1317 	 */
1318 	vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1319 	switch (vpd->device_identifier_code_set) {
1320 	case 0x01: /* Binary */
1321 		vpd->device_identifier[j++] =
1322 				hex_str[vpd->device_identifier_type];
1323 		while (i < (4 + page_83[3])) {
1324 			vpd->device_identifier[j++] =
1325 				hex_str[(page_83[i] & 0xf0) >> 4];
1326 			vpd->device_identifier[j++] =
1327 				hex_str[page_83[i] & 0x0f];
1328 			i++;
1329 		}
1330 		break;
1331 	case 0x02: /* ASCII */
1332 	case 0x03: /* UTF-8 */
1333 		while (i < (4 + page_83[3]))
1334 			vpd->device_identifier[j++] = page_83[i++];
1335 		break;
1336 	default:
1337 		break;
1338 	}
1339 
1340 	return transport_dump_vpd_ident(vpd, NULL, 0);
1341 }
1342 EXPORT_SYMBOL(transport_set_vpd_ident);
1343 
1344 static void core_setup_task_attr_emulation(struct se_device *dev)
1345 {
1346 	/*
1347 	 * If this device is from Target_Core_Mod/pSCSI, disable the
1348 	 * SAM Task Attribute emulation.
1349 	 *
1350 	 * This is currently not available in upsream Linux/SCSI Target
1351 	 * mode code, and is assumed to be disabled while using TCM/pSCSI.
1352 	 */
1353 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) {
1354 		dev->dev_task_attr_type = SAM_TASK_ATTR_PASSTHROUGH;
1355 		return;
1356 	}
1357 
1358 	dev->dev_task_attr_type = SAM_TASK_ATTR_EMULATED;
1359 	pr_debug("%s: Using SAM_TASK_ATTR_EMULATED for SPC: 0x%02x"
1360 		" device\n", dev->transport->name,
1361 		dev->transport->get_device_rev(dev));
1362 }
1363 
1364 static void scsi_dump_inquiry(struct se_device *dev)
1365 {
1366 	struct t10_wwn *wwn = &dev->se_sub_dev->t10_wwn;
1367 	int i, device_type;
1368 	/*
1369 	 * Print Linux/SCSI style INQUIRY formatting to the kernel ring buffer
1370 	 */
1371 	pr_debug("  Vendor: ");
1372 	for (i = 0; i < 8; i++)
1373 		if (wwn->vendor[i] >= 0x20)
1374 			pr_debug("%c", wwn->vendor[i]);
1375 		else
1376 			pr_debug(" ");
1377 
1378 	pr_debug("  Model: ");
1379 	for (i = 0; i < 16; i++)
1380 		if (wwn->model[i] >= 0x20)
1381 			pr_debug("%c", wwn->model[i]);
1382 		else
1383 			pr_debug(" ");
1384 
1385 	pr_debug("  Revision: ");
1386 	for (i = 0; i < 4; i++)
1387 		if (wwn->revision[i] >= 0x20)
1388 			pr_debug("%c", wwn->revision[i]);
1389 		else
1390 			pr_debug(" ");
1391 
1392 	pr_debug("\n");
1393 
1394 	device_type = dev->transport->get_device_type(dev);
1395 	pr_debug("  Type:   %s ", scsi_device_type(device_type));
1396 	pr_debug("                 ANSI SCSI revision: %02x\n",
1397 				dev->transport->get_device_rev(dev));
1398 }
1399 
1400 struct se_device *transport_add_device_to_core_hba(
1401 	struct se_hba *hba,
1402 	struct se_subsystem_api *transport,
1403 	struct se_subsystem_dev *se_dev,
1404 	u32 device_flags,
1405 	void *transport_dev,
1406 	struct se_dev_limits *dev_limits,
1407 	const char *inquiry_prod,
1408 	const char *inquiry_rev)
1409 {
1410 	int force_pt;
1411 	struct se_device  *dev;
1412 
1413 	dev = kzalloc(sizeof(struct se_device), GFP_KERNEL);
1414 	if (!dev) {
1415 		pr_err("Unable to allocate memory for se_dev_t\n");
1416 		return NULL;
1417 	}
1418 
1419 	transport_init_queue_obj(&dev->dev_queue_obj);
1420 	dev->dev_flags		= device_flags;
1421 	dev->dev_status		|= TRANSPORT_DEVICE_DEACTIVATED;
1422 	dev->dev_ptr		= transport_dev;
1423 	dev->se_hba		= hba;
1424 	dev->se_sub_dev		= se_dev;
1425 	dev->transport		= transport;
1426 	atomic_set(&dev->active_cmds, 0);
1427 	INIT_LIST_HEAD(&dev->dev_list);
1428 	INIT_LIST_HEAD(&dev->dev_sep_list);
1429 	INIT_LIST_HEAD(&dev->dev_tmr_list);
1430 	INIT_LIST_HEAD(&dev->execute_task_list);
1431 	INIT_LIST_HEAD(&dev->delayed_cmd_list);
1432 	INIT_LIST_HEAD(&dev->ordered_cmd_list);
1433 	INIT_LIST_HEAD(&dev->state_task_list);
1434 	INIT_LIST_HEAD(&dev->qf_cmd_list);
1435 	spin_lock_init(&dev->execute_task_lock);
1436 	spin_lock_init(&dev->delayed_cmd_lock);
1437 	spin_lock_init(&dev->ordered_cmd_lock);
1438 	spin_lock_init(&dev->state_task_lock);
1439 	spin_lock_init(&dev->dev_alua_lock);
1440 	spin_lock_init(&dev->dev_reservation_lock);
1441 	spin_lock_init(&dev->dev_status_lock);
1442 	spin_lock_init(&dev->dev_status_thr_lock);
1443 	spin_lock_init(&dev->se_port_lock);
1444 	spin_lock_init(&dev->se_tmr_lock);
1445 	spin_lock_init(&dev->qf_cmd_lock);
1446 
1447 	dev->queue_depth	= dev_limits->queue_depth;
1448 	atomic_set(&dev->depth_left, dev->queue_depth);
1449 	atomic_set(&dev->dev_ordered_id, 0);
1450 
1451 	se_dev_set_default_attribs(dev, dev_limits);
1452 
1453 	dev->dev_index = scsi_get_new_index(SCSI_DEVICE_INDEX);
1454 	dev->creation_time = get_jiffies_64();
1455 	spin_lock_init(&dev->stats_lock);
1456 
1457 	spin_lock(&hba->device_lock);
1458 	list_add_tail(&dev->dev_list, &hba->hba_dev_list);
1459 	hba->dev_count++;
1460 	spin_unlock(&hba->device_lock);
1461 	/*
1462 	 * Setup the SAM Task Attribute emulation for struct se_device
1463 	 */
1464 	core_setup_task_attr_emulation(dev);
1465 	/*
1466 	 * Force PR and ALUA passthrough emulation with internal object use.
1467 	 */
1468 	force_pt = (hba->hba_flags & HBA_FLAGS_INTERNAL_USE);
1469 	/*
1470 	 * Setup the Reservations infrastructure for struct se_device
1471 	 */
1472 	core_setup_reservations(dev, force_pt);
1473 	/*
1474 	 * Setup the Asymmetric Logical Unit Assignment for struct se_device
1475 	 */
1476 	if (core_setup_alua(dev, force_pt) < 0)
1477 		goto out;
1478 
1479 	/*
1480 	 * Startup the struct se_device processing thread
1481 	 */
1482 	dev->process_thread = kthread_run(transport_processing_thread, dev,
1483 					  "LIO_%s", dev->transport->name);
1484 	if (IS_ERR(dev->process_thread)) {
1485 		pr_err("Unable to create kthread: LIO_%s\n",
1486 			dev->transport->name);
1487 		goto out;
1488 	}
1489 	/*
1490 	 * Setup work_queue for QUEUE_FULL
1491 	 */
1492 	INIT_WORK(&dev->qf_work_queue, target_qf_do_work);
1493 	/*
1494 	 * Preload the initial INQUIRY const values if we are doing
1495 	 * anything virtual (IBLOCK, FILEIO, RAMDISK), but not for TCM/pSCSI
1496 	 * passthrough because this is being provided by the backend LLD.
1497 	 * This is required so that transport_get_inquiry() copies these
1498 	 * originals once back into DEV_T10_WWN(dev) for the virtual device
1499 	 * setup.
1500 	 */
1501 	if (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) {
1502 		if (!inquiry_prod || !inquiry_rev) {
1503 			pr_err("All non TCM/pSCSI plugins require"
1504 				" INQUIRY consts\n");
1505 			goto out;
1506 		}
1507 
1508 		strncpy(&dev->se_sub_dev->t10_wwn.vendor[0], "LIO-ORG", 8);
1509 		strncpy(&dev->se_sub_dev->t10_wwn.model[0], inquiry_prod, 16);
1510 		strncpy(&dev->se_sub_dev->t10_wwn.revision[0], inquiry_rev, 4);
1511 	}
1512 	scsi_dump_inquiry(dev);
1513 
1514 	return dev;
1515 out:
1516 	kthread_stop(dev->process_thread);
1517 
1518 	spin_lock(&hba->device_lock);
1519 	list_del(&dev->dev_list);
1520 	hba->dev_count--;
1521 	spin_unlock(&hba->device_lock);
1522 
1523 	se_release_vpd_for_dev(dev);
1524 
1525 	kfree(dev);
1526 
1527 	return NULL;
1528 }
1529 EXPORT_SYMBOL(transport_add_device_to_core_hba);
1530 
1531 /*	transport_generic_prepare_cdb():
1532  *
1533  *	Since the Initiator sees iSCSI devices as LUNs,  the SCSI CDB will
1534  *	contain the iSCSI LUN in bits 7-5 of byte 1 as per SAM-2.
1535  *	The point of this is since we are mapping iSCSI LUNs to
1536  *	SCSI Target IDs having a non-zero LUN in the CDB will throw the
1537  *	devices and HBAs for a loop.
1538  */
1539 static inline void transport_generic_prepare_cdb(
1540 	unsigned char *cdb)
1541 {
1542 	switch (cdb[0]) {
1543 	case READ_10: /* SBC - RDProtect */
1544 	case READ_12: /* SBC - RDProtect */
1545 	case READ_16: /* SBC - RDProtect */
1546 	case SEND_DIAGNOSTIC: /* SPC - SELF-TEST Code */
1547 	case VERIFY: /* SBC - VRProtect */
1548 	case VERIFY_16: /* SBC - VRProtect */
1549 	case WRITE_VERIFY: /* SBC - VRProtect */
1550 	case WRITE_VERIFY_12: /* SBC - VRProtect */
1551 		break;
1552 	default:
1553 		cdb[1] &= 0x1f; /* clear logical unit number */
1554 		break;
1555 	}
1556 }
1557 
1558 static struct se_task *
1559 transport_generic_get_task(struct se_cmd *cmd,
1560 		enum dma_data_direction data_direction)
1561 {
1562 	struct se_task *task;
1563 	struct se_device *dev = cmd->se_dev;
1564 
1565 	task = dev->transport->alloc_task(cmd->t_task_cdb);
1566 	if (!task) {
1567 		pr_err("Unable to allocate struct se_task\n");
1568 		return NULL;
1569 	}
1570 
1571 	INIT_LIST_HEAD(&task->t_list);
1572 	INIT_LIST_HEAD(&task->t_execute_list);
1573 	INIT_LIST_HEAD(&task->t_state_list);
1574 	init_completion(&task->task_stop_comp);
1575 	task->task_se_cmd = cmd;
1576 	task->se_dev = dev;
1577 	task->task_data_direction = data_direction;
1578 
1579 	return task;
1580 }
1581 
1582 static int transport_generic_cmd_sequencer(struct se_cmd *, unsigned char *);
1583 
1584 /*
1585  * Used by fabric modules containing a local struct se_cmd within their
1586  * fabric dependent per I/O descriptor.
1587  */
1588 void transport_init_se_cmd(
1589 	struct se_cmd *cmd,
1590 	struct target_core_fabric_ops *tfo,
1591 	struct se_session *se_sess,
1592 	u32 data_length,
1593 	int data_direction,
1594 	int task_attr,
1595 	unsigned char *sense_buffer)
1596 {
1597 	INIT_LIST_HEAD(&cmd->se_lun_node);
1598 	INIT_LIST_HEAD(&cmd->se_delayed_node);
1599 	INIT_LIST_HEAD(&cmd->se_ordered_node);
1600 	INIT_LIST_HEAD(&cmd->se_qf_node);
1601 
1602 	INIT_LIST_HEAD(&cmd->t_task_list);
1603 	init_completion(&cmd->transport_lun_fe_stop_comp);
1604 	init_completion(&cmd->transport_lun_stop_comp);
1605 	init_completion(&cmd->t_transport_stop_comp);
1606 	spin_lock_init(&cmd->t_state_lock);
1607 	atomic_set(&cmd->transport_dev_active, 1);
1608 
1609 	cmd->se_tfo = tfo;
1610 	cmd->se_sess = se_sess;
1611 	cmd->data_length = data_length;
1612 	cmd->data_direction = data_direction;
1613 	cmd->sam_task_attr = task_attr;
1614 	cmd->sense_buffer = sense_buffer;
1615 }
1616 EXPORT_SYMBOL(transport_init_se_cmd);
1617 
1618 static int transport_check_alloc_task_attr(struct se_cmd *cmd)
1619 {
1620 	/*
1621 	 * Check if SAM Task Attribute emulation is enabled for this
1622 	 * struct se_device storage object
1623 	 */
1624 	if (cmd->se_dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED)
1625 		return 0;
1626 
1627 	if (cmd->sam_task_attr == MSG_ACA_TAG) {
1628 		pr_debug("SAM Task Attribute ACA"
1629 			" emulation is not supported\n");
1630 		return -EINVAL;
1631 	}
1632 	/*
1633 	 * Used to determine when ORDERED commands should go from
1634 	 * Dormant to Active status.
1635 	 */
1636 	cmd->se_ordered_id = atomic_inc_return(&cmd->se_dev->dev_ordered_id);
1637 	smp_mb__after_atomic_inc();
1638 	pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1639 			cmd->se_ordered_id, cmd->sam_task_attr,
1640 			cmd->se_dev->transport->name);
1641 	return 0;
1642 }
1643 
1644 void transport_free_se_cmd(
1645 	struct se_cmd *se_cmd)
1646 {
1647 	if (se_cmd->se_tmr_req)
1648 		core_tmr_release_req(se_cmd->se_tmr_req);
1649 	/*
1650 	 * Check and free any extended CDB buffer that was allocated
1651 	 */
1652 	if (se_cmd->t_task_cdb != se_cmd->__t_task_cdb)
1653 		kfree(se_cmd->t_task_cdb);
1654 }
1655 EXPORT_SYMBOL(transport_free_se_cmd);
1656 
1657 static void transport_generic_wait_for_tasks(struct se_cmd *, int, int);
1658 
1659 /*	transport_generic_allocate_tasks():
1660  *
1661  *	Called from fabric RX Thread.
1662  */
1663 int transport_generic_allocate_tasks(
1664 	struct se_cmd *cmd,
1665 	unsigned char *cdb)
1666 {
1667 	int ret;
1668 
1669 	transport_generic_prepare_cdb(cdb);
1670 
1671 	/*
1672 	 * This is needed for early exceptions.
1673 	 */
1674 	cmd->transport_wait_for_tasks = &transport_generic_wait_for_tasks;
1675 
1676 	/*
1677 	 * Ensure that the received CDB is less than the max (252 + 8) bytes
1678 	 * for VARIABLE_LENGTH_CMD
1679 	 */
1680 	if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1681 		pr_err("Received SCSI CDB with command_size: %d that"
1682 			" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1683 			scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1684 		return -EINVAL;
1685 	}
1686 	/*
1687 	 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1688 	 * allocate the additional extended CDB buffer now..  Otherwise
1689 	 * setup the pointer from __t_task_cdb to t_task_cdb.
1690 	 */
1691 	if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1692 		cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1693 						GFP_KERNEL);
1694 		if (!cmd->t_task_cdb) {
1695 			pr_err("Unable to allocate cmd->t_task_cdb"
1696 				" %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1697 				scsi_command_size(cdb),
1698 				(unsigned long)sizeof(cmd->__t_task_cdb));
1699 			return -ENOMEM;
1700 		}
1701 	} else
1702 		cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1703 	/*
1704 	 * Copy the original CDB into cmd->
1705 	 */
1706 	memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1707 	/*
1708 	 * Setup the received CDB based on SCSI defined opcodes and
1709 	 * perform unit attention, persistent reservations and ALUA
1710 	 * checks for virtual device backends.  The cmd->t_task_cdb
1711 	 * pointer is expected to be setup before we reach this point.
1712 	 */
1713 	ret = transport_generic_cmd_sequencer(cmd, cdb);
1714 	if (ret < 0)
1715 		return ret;
1716 	/*
1717 	 * Check for SAM Task Attribute Emulation
1718 	 */
1719 	if (transport_check_alloc_task_attr(cmd) < 0) {
1720 		cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1721 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
1722 		return -EINVAL;
1723 	}
1724 	spin_lock(&cmd->se_lun->lun_sep_lock);
1725 	if (cmd->se_lun->lun_sep)
1726 		cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1727 	spin_unlock(&cmd->se_lun->lun_sep_lock);
1728 	return 0;
1729 }
1730 EXPORT_SYMBOL(transport_generic_allocate_tasks);
1731 
1732 /*
1733  * Used by fabric module frontends not defining a TFO->new_cmd_map()
1734  * to queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD statis
1735  */
1736 int transport_generic_handle_cdb(
1737 	struct se_cmd *cmd)
1738 {
1739 	if (!cmd->se_lun) {
1740 		dump_stack();
1741 		pr_err("cmd->se_lun is NULL\n");
1742 		return -EINVAL;
1743 	}
1744 
1745 	transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD);
1746 	return 0;
1747 }
1748 EXPORT_SYMBOL(transport_generic_handle_cdb);
1749 
1750 /*
1751  * Used by fabric module frontends to queue tasks directly.
1752  * Many only be used from process context only
1753  */
1754 int transport_handle_cdb_direct(
1755 	struct se_cmd *cmd)
1756 {
1757 	if (!cmd->se_lun) {
1758 		dump_stack();
1759 		pr_err("cmd->se_lun is NULL\n");
1760 		return -EINVAL;
1761 	}
1762 	if (in_interrupt()) {
1763 		dump_stack();
1764 		pr_err("transport_generic_handle_cdb cannot be called"
1765 				" from interrupt context\n");
1766 		return -EINVAL;
1767 	}
1768 
1769 	return transport_generic_new_cmd(cmd);
1770 }
1771 EXPORT_SYMBOL(transport_handle_cdb_direct);
1772 
1773 /*
1774  * Used by fabric module frontends defining a TFO->new_cmd_map() caller
1775  * to  queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD_MAP in order to
1776  * complete setup in TCM process context w/ TFO->new_cmd_map().
1777  */
1778 int transport_generic_handle_cdb_map(
1779 	struct se_cmd *cmd)
1780 {
1781 	if (!cmd->se_lun) {
1782 		dump_stack();
1783 		pr_err("cmd->se_lun is NULL\n");
1784 		return -EINVAL;
1785 	}
1786 
1787 	transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD_MAP);
1788 	return 0;
1789 }
1790 EXPORT_SYMBOL(transport_generic_handle_cdb_map);
1791 
1792 /*	transport_generic_handle_data():
1793  *
1794  *
1795  */
1796 int transport_generic_handle_data(
1797 	struct se_cmd *cmd)
1798 {
1799 	/*
1800 	 * For the software fabric case, then we assume the nexus is being
1801 	 * failed/shutdown when signals are pending from the kthread context
1802 	 * caller, so we return a failure.  For the HW target mode case running
1803 	 * in interrupt code, the signal_pending() check is skipped.
1804 	 */
1805 	if (!in_interrupt() && signal_pending(current))
1806 		return -EPERM;
1807 	/*
1808 	 * If the received CDB has aleady been ABORTED by the generic
1809 	 * target engine, we now call transport_check_aborted_status()
1810 	 * to queue any delated TASK_ABORTED status for the received CDB to the
1811 	 * fabric module as we are expecting no further incoming DATA OUT
1812 	 * sequences at this point.
1813 	 */
1814 	if (transport_check_aborted_status(cmd, 1) != 0)
1815 		return 0;
1816 
1817 	transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_WRITE);
1818 	return 0;
1819 }
1820 EXPORT_SYMBOL(transport_generic_handle_data);
1821 
1822 /*	transport_generic_handle_tmr():
1823  *
1824  *
1825  */
1826 int transport_generic_handle_tmr(
1827 	struct se_cmd *cmd)
1828 {
1829 	/*
1830 	 * This is needed for early exceptions.
1831 	 */
1832 	cmd->transport_wait_for_tasks = &transport_generic_wait_for_tasks;
1833 
1834 	transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_TMR);
1835 	return 0;
1836 }
1837 EXPORT_SYMBOL(transport_generic_handle_tmr);
1838 
1839 void transport_generic_free_cmd_intr(
1840 	struct se_cmd *cmd)
1841 {
1842 	transport_add_cmd_to_queue(cmd, TRANSPORT_FREE_CMD_INTR);
1843 }
1844 EXPORT_SYMBOL(transport_generic_free_cmd_intr);
1845 
1846 static int transport_stop_tasks_for_cmd(struct se_cmd *cmd)
1847 {
1848 	struct se_task *task, *task_tmp;
1849 	unsigned long flags;
1850 	int ret = 0;
1851 
1852 	pr_debug("ITT[0x%08x] - Stopping tasks\n",
1853 		cmd->se_tfo->get_task_tag(cmd));
1854 
1855 	/*
1856 	 * No tasks remain in the execution queue
1857 	 */
1858 	spin_lock_irqsave(&cmd->t_state_lock, flags);
1859 	list_for_each_entry_safe(task, task_tmp,
1860 				&cmd->t_task_list, t_list) {
1861 		pr_debug("task_no[%d] - Processing task %p\n",
1862 				task->task_no, task);
1863 		/*
1864 		 * If the struct se_task has not been sent and is not active,
1865 		 * remove the struct se_task from the execution queue.
1866 		 */
1867 		if (!atomic_read(&task->task_sent) &&
1868 		    !atomic_read(&task->task_active)) {
1869 			spin_unlock_irqrestore(&cmd->t_state_lock,
1870 					flags);
1871 			transport_remove_task_from_execute_queue(task,
1872 					task->se_dev);
1873 
1874 			pr_debug("task_no[%d] - Removed from execute queue\n",
1875 				task->task_no);
1876 			spin_lock_irqsave(&cmd->t_state_lock, flags);
1877 			continue;
1878 		}
1879 
1880 		/*
1881 		 * If the struct se_task is active, sleep until it is returned
1882 		 * from the plugin.
1883 		 */
1884 		if (atomic_read(&task->task_active)) {
1885 			atomic_set(&task->task_stop, 1);
1886 			spin_unlock_irqrestore(&cmd->t_state_lock,
1887 					flags);
1888 
1889 			pr_debug("task_no[%d] - Waiting to complete\n",
1890 				task->task_no);
1891 			wait_for_completion(&task->task_stop_comp);
1892 			pr_debug("task_no[%d] - Stopped successfully\n",
1893 				task->task_no);
1894 
1895 			spin_lock_irqsave(&cmd->t_state_lock, flags);
1896 			atomic_dec(&cmd->t_task_cdbs_left);
1897 
1898 			atomic_set(&task->task_active, 0);
1899 			atomic_set(&task->task_stop, 0);
1900 		} else {
1901 			pr_debug("task_no[%d] - Did nothing\n", task->task_no);
1902 			ret++;
1903 		}
1904 
1905 		__transport_stop_task_timer(task, &flags);
1906 	}
1907 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1908 
1909 	return ret;
1910 }
1911 
1912 /*
1913  * Handle SAM-esque emulation for generic transport request failures.
1914  */
1915 static void transport_generic_request_failure(
1916 	struct se_cmd *cmd,
1917 	struct se_device *dev,
1918 	int complete,
1919 	int sc)
1920 {
1921 	int ret = 0;
1922 
1923 	pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1924 		" CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1925 		cmd->t_task_cdb[0]);
1926 	pr_debug("-----[ i_state: %d t_state/def_t_state:"
1927 		" %d/%d transport_error_status: %d\n",
1928 		cmd->se_tfo->get_cmd_state(cmd),
1929 		cmd->t_state, cmd->deferred_t_state,
1930 		cmd->transport_error_status);
1931 	pr_debug("-----[ t_tasks: %d t_task_cdbs_left: %d"
1932 		" t_task_cdbs_sent: %d t_task_cdbs_ex_left: %d --"
1933 		" t_transport_active: %d t_transport_stop: %d"
1934 		" t_transport_sent: %d\n", cmd->t_task_list_num,
1935 		atomic_read(&cmd->t_task_cdbs_left),
1936 		atomic_read(&cmd->t_task_cdbs_sent),
1937 		atomic_read(&cmd->t_task_cdbs_ex_left),
1938 		atomic_read(&cmd->t_transport_active),
1939 		atomic_read(&cmd->t_transport_stop),
1940 		atomic_read(&cmd->t_transport_sent));
1941 
1942 	transport_stop_all_task_timers(cmd);
1943 
1944 	if (dev)
1945 		atomic_inc(&dev->depth_left);
1946 	/*
1947 	 * For SAM Task Attribute emulation for failed struct se_cmd
1948 	 */
1949 	if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
1950 		transport_complete_task_attr(cmd);
1951 
1952 	if (complete) {
1953 		transport_direct_request_timeout(cmd);
1954 		cmd->transport_error_status = PYX_TRANSPORT_LU_COMM_FAILURE;
1955 	}
1956 
1957 	switch (cmd->transport_error_status) {
1958 	case PYX_TRANSPORT_UNKNOWN_SAM_OPCODE:
1959 		cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1960 		break;
1961 	case PYX_TRANSPORT_REQ_TOO_MANY_SECTORS:
1962 		cmd->scsi_sense_reason = TCM_SECTOR_COUNT_TOO_MANY;
1963 		break;
1964 	case PYX_TRANSPORT_INVALID_CDB_FIELD:
1965 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
1966 		break;
1967 	case PYX_TRANSPORT_INVALID_PARAMETER_LIST:
1968 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1969 		break;
1970 	case PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES:
1971 		if (!sc)
1972 			transport_new_cmd_failure(cmd);
1973 		/*
1974 		 * Currently for PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES,
1975 		 * we force this session to fall back to session
1976 		 * recovery.
1977 		 */
1978 		cmd->se_tfo->fall_back_to_erl0(cmd->se_sess);
1979 		cmd->se_tfo->stop_session(cmd->se_sess, 0, 0);
1980 
1981 		goto check_stop;
1982 	case PYX_TRANSPORT_LU_COMM_FAILURE:
1983 	case PYX_TRANSPORT_ILLEGAL_REQUEST:
1984 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1985 		break;
1986 	case PYX_TRANSPORT_UNKNOWN_MODE_PAGE:
1987 		cmd->scsi_sense_reason = TCM_UNKNOWN_MODE_PAGE;
1988 		break;
1989 	case PYX_TRANSPORT_WRITE_PROTECTED:
1990 		cmd->scsi_sense_reason = TCM_WRITE_PROTECTED;
1991 		break;
1992 	case PYX_TRANSPORT_RESERVATION_CONFLICT:
1993 		/*
1994 		 * No SENSE Data payload for this case, set SCSI Status
1995 		 * and queue the response to $FABRIC_MOD.
1996 		 *
1997 		 * Uses linux/include/scsi/scsi.h SAM status codes defs
1998 		 */
1999 		cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
2000 		/*
2001 		 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
2002 		 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
2003 		 * CONFLICT STATUS.
2004 		 *
2005 		 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
2006 		 */
2007 		if (cmd->se_sess &&
2008 		    cmd->se_dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 2)
2009 			core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
2010 				cmd->orig_fe_lun, 0x2C,
2011 				ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
2012 
2013 		ret = cmd->se_tfo->queue_status(cmd);
2014 		if (ret == -EAGAIN)
2015 			goto queue_full;
2016 		goto check_stop;
2017 	case PYX_TRANSPORT_USE_SENSE_REASON:
2018 		/*
2019 		 * struct se_cmd->scsi_sense_reason already set
2020 		 */
2021 		break;
2022 	default:
2023 		pr_err("Unknown transport error for CDB 0x%02x: %d\n",
2024 			cmd->t_task_cdb[0],
2025 			cmd->transport_error_status);
2026 		cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
2027 		break;
2028 	}
2029 
2030 	if (!sc)
2031 		transport_new_cmd_failure(cmd);
2032 	else {
2033 		ret = transport_send_check_condition_and_sense(cmd,
2034 				cmd->scsi_sense_reason, 0);
2035 		if (ret == -EAGAIN)
2036 			goto queue_full;
2037 	}
2038 
2039 check_stop:
2040 	transport_lun_remove_cmd(cmd);
2041 	if (!transport_cmd_check_stop_to_fabric(cmd))
2042 		;
2043 	return;
2044 
2045 queue_full:
2046 	cmd->t_state = TRANSPORT_COMPLETE_OK;
2047 	transport_handle_queue_full(cmd, cmd->se_dev, transport_complete_qf);
2048 }
2049 
2050 static void transport_direct_request_timeout(struct se_cmd *cmd)
2051 {
2052 	unsigned long flags;
2053 
2054 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2055 	if (!atomic_read(&cmd->t_transport_timeout)) {
2056 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2057 		return;
2058 	}
2059 	if (atomic_read(&cmd->t_task_cdbs_timeout_left)) {
2060 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2061 		return;
2062 	}
2063 
2064 	atomic_sub(atomic_read(&cmd->t_transport_timeout),
2065 		   &cmd->t_se_count);
2066 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2067 }
2068 
2069 static void transport_generic_request_timeout(struct se_cmd *cmd)
2070 {
2071 	unsigned long flags;
2072 
2073 	/*
2074 	 * Reset cmd->t_se_count to allow transport_generic_remove()
2075 	 * to allow last call to free memory resources.
2076 	 */
2077 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2078 	if (atomic_read(&cmd->t_transport_timeout) > 1) {
2079 		int tmp = (atomic_read(&cmd->t_transport_timeout) - 1);
2080 
2081 		atomic_sub(tmp, &cmd->t_se_count);
2082 	}
2083 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2084 
2085 	transport_generic_remove(cmd, 0);
2086 }
2087 
2088 static inline u32 transport_lba_21(unsigned char *cdb)
2089 {
2090 	return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
2091 }
2092 
2093 static inline u32 transport_lba_32(unsigned char *cdb)
2094 {
2095 	return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
2096 }
2097 
2098 static inline unsigned long long transport_lba_64(unsigned char *cdb)
2099 {
2100 	unsigned int __v1, __v2;
2101 
2102 	__v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
2103 	__v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
2104 
2105 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
2106 }
2107 
2108 /*
2109  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
2110  */
2111 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
2112 {
2113 	unsigned int __v1, __v2;
2114 
2115 	__v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
2116 	__v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
2117 
2118 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
2119 }
2120 
2121 static void transport_set_supported_SAM_opcode(struct se_cmd *se_cmd)
2122 {
2123 	unsigned long flags;
2124 
2125 	spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2126 	se_cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
2127 	spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2128 }
2129 
2130 /*
2131  * Called from interrupt context.
2132  */
2133 static void transport_task_timeout_handler(unsigned long data)
2134 {
2135 	struct se_task *task = (struct se_task *)data;
2136 	struct se_cmd *cmd = task->task_se_cmd;
2137 	unsigned long flags;
2138 
2139 	pr_debug("transport task timeout fired! task: %p cmd: %p\n", task, cmd);
2140 
2141 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2142 	if (task->task_flags & TF_STOP) {
2143 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2144 		return;
2145 	}
2146 	task->task_flags &= ~TF_RUNNING;
2147 
2148 	/*
2149 	 * Determine if transport_complete_task() has already been called.
2150 	 */
2151 	if (!atomic_read(&task->task_active)) {
2152 		pr_debug("transport task: %p cmd: %p timeout task_active"
2153 				" == 0\n", task, cmd);
2154 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2155 		return;
2156 	}
2157 
2158 	atomic_inc(&cmd->t_se_count);
2159 	atomic_inc(&cmd->t_transport_timeout);
2160 	cmd->t_tasks_failed = 1;
2161 
2162 	atomic_set(&task->task_timeout, 1);
2163 	task->task_error_status = PYX_TRANSPORT_TASK_TIMEOUT;
2164 	task->task_scsi_status = 1;
2165 
2166 	if (atomic_read(&task->task_stop)) {
2167 		pr_debug("transport task: %p cmd: %p timeout task_stop"
2168 				" == 1\n", task, cmd);
2169 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2170 		complete(&task->task_stop_comp);
2171 		return;
2172 	}
2173 
2174 	if (!atomic_dec_and_test(&cmd->t_task_cdbs_left)) {
2175 		pr_debug("transport task: %p cmd: %p timeout non zero"
2176 				" t_task_cdbs_left\n", task, cmd);
2177 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2178 		return;
2179 	}
2180 	pr_debug("transport task: %p cmd: %p timeout ZERO t_task_cdbs_left\n",
2181 			task, cmd);
2182 
2183 	cmd->t_state = TRANSPORT_COMPLETE_FAILURE;
2184 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2185 
2186 	transport_add_cmd_to_queue(cmd, TRANSPORT_COMPLETE_FAILURE);
2187 }
2188 
2189 /*
2190  * Called with cmd->t_state_lock held.
2191  */
2192 static void transport_start_task_timer(struct se_task *task)
2193 {
2194 	struct se_device *dev = task->se_dev;
2195 	int timeout;
2196 
2197 	if (task->task_flags & TF_RUNNING)
2198 		return;
2199 	/*
2200 	 * If the task_timeout is disabled, exit now.
2201 	 */
2202 	timeout = dev->se_sub_dev->se_dev_attrib.task_timeout;
2203 	if (!timeout)
2204 		return;
2205 
2206 	init_timer(&task->task_timer);
2207 	task->task_timer.expires = (get_jiffies_64() + timeout * HZ);
2208 	task->task_timer.data = (unsigned long) task;
2209 	task->task_timer.function = transport_task_timeout_handler;
2210 
2211 	task->task_flags |= TF_RUNNING;
2212 	add_timer(&task->task_timer);
2213 #if 0
2214 	pr_debug("Starting task timer for cmd: %p task: %p seconds:"
2215 		" %d\n", task->task_se_cmd, task, timeout);
2216 #endif
2217 }
2218 
2219 /*
2220  * Called with spin_lock_irq(&cmd->t_state_lock) held.
2221  */
2222 void __transport_stop_task_timer(struct se_task *task, unsigned long *flags)
2223 {
2224 	struct se_cmd *cmd = task->task_se_cmd;
2225 
2226 	if (!task->task_flags & TF_RUNNING)
2227 		return;
2228 
2229 	task->task_flags |= TF_STOP;
2230 	spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2231 
2232 	del_timer_sync(&task->task_timer);
2233 
2234 	spin_lock_irqsave(&cmd->t_state_lock, *flags);
2235 	task->task_flags &= ~TF_RUNNING;
2236 	task->task_flags &= ~TF_STOP;
2237 }
2238 
2239 static void transport_stop_all_task_timers(struct se_cmd *cmd)
2240 {
2241 	struct se_task *task = NULL, *task_tmp;
2242 	unsigned long flags;
2243 
2244 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2245 	list_for_each_entry_safe(task, task_tmp,
2246 				&cmd->t_task_list, t_list)
2247 		__transport_stop_task_timer(task, &flags);
2248 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2249 }
2250 
2251 static inline int transport_tcq_window_closed(struct se_device *dev)
2252 {
2253 	if (dev->dev_tcq_window_closed++ <
2254 			PYX_TRANSPORT_WINDOW_CLOSED_THRESHOLD) {
2255 		msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_SHORT);
2256 	} else
2257 		msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_LONG);
2258 
2259 	wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
2260 	return 0;
2261 }
2262 
2263 /*
2264  * Called from Fabric Module context from transport_execute_tasks()
2265  *
2266  * The return of this function determins if the tasks from struct se_cmd
2267  * get added to the execution queue in transport_execute_tasks(),
2268  * or are added to the delayed or ordered lists here.
2269  */
2270 static inline int transport_execute_task_attr(struct se_cmd *cmd)
2271 {
2272 	if (cmd->se_dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED)
2273 		return 1;
2274 	/*
2275 	 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
2276 	 * to allow the passed struct se_cmd list of tasks to the front of the list.
2277 	 */
2278 	 if (cmd->sam_task_attr == MSG_HEAD_TAG) {
2279 		atomic_inc(&cmd->se_dev->dev_hoq_count);
2280 		smp_mb__after_atomic_inc();
2281 		pr_debug("Added HEAD_OF_QUEUE for CDB:"
2282 			" 0x%02x, se_ordered_id: %u\n",
2283 			cmd->t_task_cdb[0],
2284 			cmd->se_ordered_id);
2285 		return 1;
2286 	} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
2287 		spin_lock(&cmd->se_dev->ordered_cmd_lock);
2288 		list_add_tail(&cmd->se_ordered_node,
2289 				&cmd->se_dev->ordered_cmd_list);
2290 		spin_unlock(&cmd->se_dev->ordered_cmd_lock);
2291 
2292 		atomic_inc(&cmd->se_dev->dev_ordered_sync);
2293 		smp_mb__after_atomic_inc();
2294 
2295 		pr_debug("Added ORDERED for CDB: 0x%02x to ordered"
2296 				" list, se_ordered_id: %u\n",
2297 				cmd->t_task_cdb[0],
2298 				cmd->se_ordered_id);
2299 		/*
2300 		 * Add ORDERED command to tail of execution queue if
2301 		 * no other older commands exist that need to be
2302 		 * completed first.
2303 		 */
2304 		if (!atomic_read(&cmd->se_dev->simple_cmds))
2305 			return 1;
2306 	} else {
2307 		/*
2308 		 * For SIMPLE and UNTAGGED Task Attribute commands
2309 		 */
2310 		atomic_inc(&cmd->se_dev->simple_cmds);
2311 		smp_mb__after_atomic_inc();
2312 	}
2313 	/*
2314 	 * Otherwise if one or more outstanding ORDERED task attribute exist,
2315 	 * add the dormant task(s) built for the passed struct se_cmd to the
2316 	 * execution queue and become in Active state for this struct se_device.
2317 	 */
2318 	if (atomic_read(&cmd->se_dev->dev_ordered_sync) != 0) {
2319 		/*
2320 		 * Otherwise, add cmd w/ tasks to delayed cmd queue that
2321 		 * will be drained upon completion of HEAD_OF_QUEUE task.
2322 		 */
2323 		spin_lock(&cmd->se_dev->delayed_cmd_lock);
2324 		cmd->se_cmd_flags |= SCF_DELAYED_CMD_FROM_SAM_ATTR;
2325 		list_add_tail(&cmd->se_delayed_node,
2326 				&cmd->se_dev->delayed_cmd_list);
2327 		spin_unlock(&cmd->se_dev->delayed_cmd_lock);
2328 
2329 		pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
2330 			" delayed CMD list, se_ordered_id: %u\n",
2331 			cmd->t_task_cdb[0], cmd->sam_task_attr,
2332 			cmd->se_ordered_id);
2333 		/*
2334 		 * Return zero to let transport_execute_tasks() know
2335 		 * not to add the delayed tasks to the execution list.
2336 		 */
2337 		return 0;
2338 	}
2339 	/*
2340 	 * Otherwise, no ORDERED task attributes exist..
2341 	 */
2342 	return 1;
2343 }
2344 
2345 /*
2346  * Called from fabric module context in transport_generic_new_cmd() and
2347  * transport_generic_process_write()
2348  */
2349 static int transport_execute_tasks(struct se_cmd *cmd)
2350 {
2351 	int add_tasks;
2352 
2353 	if (se_dev_check_online(cmd->se_orig_obj_ptr) != 0) {
2354 		cmd->transport_error_status = PYX_TRANSPORT_LU_COMM_FAILURE;
2355 		transport_generic_request_failure(cmd, NULL, 0, 1);
2356 		return 0;
2357 	}
2358 
2359 	/*
2360 	 * Call transport_cmd_check_stop() to see if a fabric exception
2361 	 * has occurred that prevents execution.
2362 	 */
2363 	if (!transport_cmd_check_stop(cmd, 0, TRANSPORT_PROCESSING)) {
2364 		/*
2365 		 * Check for SAM Task Attribute emulation and HEAD_OF_QUEUE
2366 		 * attribute for the tasks of the received struct se_cmd CDB
2367 		 */
2368 		add_tasks = transport_execute_task_attr(cmd);
2369 		if (!add_tasks)
2370 			goto execute_tasks;
2371 		/*
2372 		 * This calls transport_add_tasks_from_cmd() to handle
2373 		 * HEAD_OF_QUEUE ordering for SAM Task Attribute emulation
2374 		 * (if enabled) in __transport_add_task_to_execute_queue() and
2375 		 * transport_add_task_check_sam_attr().
2376 		 */
2377 		transport_add_tasks_from_cmd(cmd);
2378 	}
2379 	/*
2380 	 * Kick the execution queue for the cmd associated struct se_device
2381 	 * storage object.
2382 	 */
2383 execute_tasks:
2384 	__transport_execute_tasks(cmd->se_dev);
2385 	return 0;
2386 }
2387 
2388 /*
2389  * Called to check struct se_device tcq depth window, and once open pull struct se_task
2390  * from struct se_device->execute_task_list and
2391  *
2392  * Called from transport_processing_thread()
2393  */
2394 static int __transport_execute_tasks(struct se_device *dev)
2395 {
2396 	int error;
2397 	struct se_cmd *cmd = NULL;
2398 	struct se_task *task = NULL;
2399 	unsigned long flags;
2400 
2401 	/*
2402 	 * Check if there is enough room in the device and HBA queue to send
2403 	 * struct se_tasks to the selected transport.
2404 	 */
2405 check_depth:
2406 	if (!atomic_read(&dev->depth_left))
2407 		return transport_tcq_window_closed(dev);
2408 
2409 	dev->dev_tcq_window_closed = 0;
2410 
2411 	spin_lock_irq(&dev->execute_task_lock);
2412 	if (list_empty(&dev->execute_task_list)) {
2413 		spin_unlock_irq(&dev->execute_task_lock);
2414 		return 0;
2415 	}
2416 	task = list_first_entry(&dev->execute_task_list,
2417 				struct se_task, t_execute_list);
2418 	list_del(&task->t_execute_list);
2419 	atomic_set(&task->task_execute_queue, 0);
2420 	atomic_dec(&dev->execute_tasks);
2421 	spin_unlock_irq(&dev->execute_task_lock);
2422 
2423 	atomic_dec(&dev->depth_left);
2424 
2425 	cmd = task->task_se_cmd;
2426 
2427 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2428 	atomic_set(&task->task_active, 1);
2429 	atomic_set(&task->task_sent, 1);
2430 	atomic_inc(&cmd->t_task_cdbs_sent);
2431 
2432 	if (atomic_read(&cmd->t_task_cdbs_sent) ==
2433 	    cmd->t_task_list_num)
2434 		atomic_set(&cmd->transport_sent, 1);
2435 
2436 	transport_start_task_timer(task);
2437 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2438 	/*
2439 	 * The struct se_cmd->transport_emulate_cdb() function pointer is used
2440 	 * to grab REPORT_LUNS and other CDBs we want to handle before they hit the
2441 	 * struct se_subsystem_api->do_task() caller below.
2442 	 */
2443 	if (cmd->transport_emulate_cdb) {
2444 		error = cmd->transport_emulate_cdb(cmd);
2445 		if (error != 0) {
2446 			cmd->transport_error_status = error;
2447 			atomic_set(&task->task_active, 0);
2448 			atomic_set(&cmd->transport_sent, 0);
2449 			transport_stop_tasks_for_cmd(cmd);
2450 			transport_generic_request_failure(cmd, dev, 0, 1);
2451 			goto check_depth;
2452 		}
2453 		/*
2454 		 * Handle the successful completion for transport_emulate_cdb()
2455 		 * for synchronous operation, following SCF_EMULATE_CDB_ASYNC
2456 		 * Otherwise the caller is expected to complete the task with
2457 		 * proper status.
2458 		 */
2459 		if (!(cmd->se_cmd_flags & SCF_EMULATE_CDB_ASYNC)) {
2460 			cmd->scsi_status = SAM_STAT_GOOD;
2461 			task->task_scsi_status = GOOD;
2462 			transport_complete_task(task, 1);
2463 		}
2464 	} else {
2465 		/*
2466 		 * Currently for all virtual TCM plugins including IBLOCK, FILEIO and
2467 		 * RAMDISK we use the internal transport_emulate_control_cdb() logic
2468 		 * with struct se_subsystem_api callers for the primary SPC-3 TYPE_DISK
2469 		 * LUN emulation code.
2470 		 *
2471 		 * For TCM/pSCSI and all other SCF_SCSI_DATA_SG_IO_CDB I/O tasks we
2472 		 * call ->do_task() directly and let the underlying TCM subsystem plugin
2473 		 * code handle the CDB emulation.
2474 		 */
2475 		if ((dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) &&
2476 		    (!(task->task_se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)))
2477 			error = transport_emulate_control_cdb(task);
2478 		else
2479 			error = dev->transport->do_task(task);
2480 
2481 		if (error != 0) {
2482 			cmd->transport_error_status = error;
2483 			atomic_set(&task->task_active, 0);
2484 			atomic_set(&cmd->transport_sent, 0);
2485 			transport_stop_tasks_for_cmd(cmd);
2486 			transport_generic_request_failure(cmd, dev, 0, 1);
2487 		}
2488 	}
2489 
2490 	goto check_depth;
2491 
2492 	return 0;
2493 }
2494 
2495 void transport_new_cmd_failure(struct se_cmd *se_cmd)
2496 {
2497 	unsigned long flags;
2498 	/*
2499 	 * Any unsolicited data will get dumped for failed command inside of
2500 	 * the fabric plugin
2501 	 */
2502 	spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2503 	se_cmd->se_cmd_flags |= SCF_SE_CMD_FAILED;
2504 	se_cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2505 	spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2506 }
2507 
2508 static void transport_nop_wait_for_tasks(struct se_cmd *, int, int);
2509 
2510 static inline u32 transport_get_sectors_6(
2511 	unsigned char *cdb,
2512 	struct se_cmd *cmd,
2513 	int *ret)
2514 {
2515 	struct se_device *dev = cmd->se_dev;
2516 
2517 	/*
2518 	 * Assume TYPE_DISK for non struct se_device objects.
2519 	 * Use 8-bit sector value.
2520 	 */
2521 	if (!dev)
2522 		goto type_disk;
2523 
2524 	/*
2525 	 * Use 24-bit allocation length for TYPE_TAPE.
2526 	 */
2527 	if (dev->transport->get_device_type(dev) == TYPE_TAPE)
2528 		return (u32)(cdb[2] << 16) + (cdb[3] << 8) + cdb[4];
2529 
2530 	/*
2531 	 * Everything else assume TYPE_DISK Sector CDB location.
2532 	 * Use 8-bit sector value.
2533 	 */
2534 type_disk:
2535 	return (u32)cdb[4];
2536 }
2537 
2538 static inline u32 transport_get_sectors_10(
2539 	unsigned char *cdb,
2540 	struct se_cmd *cmd,
2541 	int *ret)
2542 {
2543 	struct se_device *dev = cmd->se_dev;
2544 
2545 	/*
2546 	 * Assume TYPE_DISK for non struct se_device objects.
2547 	 * Use 16-bit sector value.
2548 	 */
2549 	if (!dev)
2550 		goto type_disk;
2551 
2552 	/*
2553 	 * XXX_10 is not defined in SSC, throw an exception
2554 	 */
2555 	if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2556 		*ret = -EINVAL;
2557 		return 0;
2558 	}
2559 
2560 	/*
2561 	 * Everything else assume TYPE_DISK Sector CDB location.
2562 	 * Use 16-bit sector value.
2563 	 */
2564 type_disk:
2565 	return (u32)(cdb[7] << 8) + cdb[8];
2566 }
2567 
2568 static inline u32 transport_get_sectors_12(
2569 	unsigned char *cdb,
2570 	struct se_cmd *cmd,
2571 	int *ret)
2572 {
2573 	struct se_device *dev = cmd->se_dev;
2574 
2575 	/*
2576 	 * Assume TYPE_DISK for non struct se_device objects.
2577 	 * Use 32-bit sector value.
2578 	 */
2579 	if (!dev)
2580 		goto type_disk;
2581 
2582 	/*
2583 	 * XXX_12 is not defined in SSC, throw an exception
2584 	 */
2585 	if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2586 		*ret = -EINVAL;
2587 		return 0;
2588 	}
2589 
2590 	/*
2591 	 * Everything else assume TYPE_DISK Sector CDB location.
2592 	 * Use 32-bit sector value.
2593 	 */
2594 type_disk:
2595 	return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
2596 }
2597 
2598 static inline u32 transport_get_sectors_16(
2599 	unsigned char *cdb,
2600 	struct se_cmd *cmd,
2601 	int *ret)
2602 {
2603 	struct se_device *dev = cmd->se_dev;
2604 
2605 	/*
2606 	 * Assume TYPE_DISK for non struct se_device objects.
2607 	 * Use 32-bit sector value.
2608 	 */
2609 	if (!dev)
2610 		goto type_disk;
2611 
2612 	/*
2613 	 * Use 24-bit allocation length for TYPE_TAPE.
2614 	 */
2615 	if (dev->transport->get_device_type(dev) == TYPE_TAPE)
2616 		return (u32)(cdb[12] << 16) + (cdb[13] << 8) + cdb[14];
2617 
2618 type_disk:
2619 	return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
2620 		    (cdb[12] << 8) + cdb[13];
2621 }
2622 
2623 /*
2624  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
2625  */
2626 static inline u32 transport_get_sectors_32(
2627 	unsigned char *cdb,
2628 	struct se_cmd *cmd,
2629 	int *ret)
2630 {
2631 	/*
2632 	 * Assume TYPE_DISK for non struct se_device objects.
2633 	 * Use 32-bit sector value.
2634 	 */
2635 	return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
2636 		    (cdb[30] << 8) + cdb[31];
2637 
2638 }
2639 
2640 static inline u32 transport_get_size(
2641 	u32 sectors,
2642 	unsigned char *cdb,
2643 	struct se_cmd *cmd)
2644 {
2645 	struct se_device *dev = cmd->se_dev;
2646 
2647 	if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2648 		if (cdb[1] & 1) { /* sectors */
2649 			return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
2650 		} else /* bytes */
2651 			return sectors;
2652 	}
2653 #if 0
2654 	pr_debug("Returning block_size: %u, sectors: %u == %u for"
2655 			" %s object\n", dev->se_sub_dev->se_dev_attrib.block_size, sectors,
2656 			dev->se_sub_dev->se_dev_attrib.block_size * sectors,
2657 			dev->transport->name);
2658 #endif
2659 	return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
2660 }
2661 
2662 static void transport_xor_callback(struct se_cmd *cmd)
2663 {
2664 	unsigned char *buf, *addr;
2665 	struct scatterlist *sg;
2666 	unsigned int offset;
2667 	int i;
2668 	int count;
2669 	/*
2670 	 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
2671 	 *
2672 	 * 1) read the specified logical block(s);
2673 	 * 2) transfer logical blocks from the data-out buffer;
2674 	 * 3) XOR the logical blocks transferred from the data-out buffer with
2675 	 *    the logical blocks read, storing the resulting XOR data in a buffer;
2676 	 * 4) if the DISABLE WRITE bit is set to zero, then write the logical
2677 	 *    blocks transferred from the data-out buffer; and
2678 	 * 5) transfer the resulting XOR data to the data-in buffer.
2679 	 */
2680 	buf = kmalloc(cmd->data_length, GFP_KERNEL);
2681 	if (!buf) {
2682 		pr_err("Unable to allocate xor_callback buf\n");
2683 		return;
2684 	}
2685 	/*
2686 	 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
2687 	 * into the locally allocated *buf
2688 	 */
2689 	sg_copy_to_buffer(cmd->t_data_sg,
2690 			  cmd->t_data_nents,
2691 			  buf,
2692 			  cmd->data_length);
2693 
2694 	/*
2695 	 * Now perform the XOR against the BIDI read memory located at
2696 	 * cmd->t_mem_bidi_list
2697 	 */
2698 
2699 	offset = 0;
2700 	for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
2701 		addr = kmap_atomic(sg_page(sg), KM_USER0);
2702 		if (!addr)
2703 			goto out;
2704 
2705 		for (i = 0; i < sg->length; i++)
2706 			*(addr + sg->offset + i) ^= *(buf + offset + i);
2707 
2708 		offset += sg->length;
2709 		kunmap_atomic(addr, KM_USER0);
2710 	}
2711 
2712 out:
2713 	kfree(buf);
2714 }
2715 
2716 /*
2717  * Used to obtain Sense Data from underlying Linux/SCSI struct scsi_cmnd
2718  */
2719 static int transport_get_sense_data(struct se_cmd *cmd)
2720 {
2721 	unsigned char *buffer = cmd->sense_buffer, *sense_buffer = NULL;
2722 	struct se_device *dev;
2723 	struct se_task *task = NULL, *task_tmp;
2724 	unsigned long flags;
2725 	u32 offset = 0;
2726 
2727 	WARN_ON(!cmd->se_lun);
2728 
2729 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2730 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2731 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2732 		return 0;
2733 	}
2734 
2735 	list_for_each_entry_safe(task, task_tmp,
2736 				&cmd->t_task_list, t_list) {
2737 
2738 		if (!task->task_sense)
2739 			continue;
2740 
2741 		dev = task->se_dev;
2742 		if (!dev)
2743 			continue;
2744 
2745 		if (!dev->transport->get_sense_buffer) {
2746 			pr_err("dev->transport->get_sense_buffer"
2747 					" is NULL\n");
2748 			continue;
2749 		}
2750 
2751 		sense_buffer = dev->transport->get_sense_buffer(task);
2752 		if (!sense_buffer) {
2753 			pr_err("ITT[0x%08x]_TASK[%d]: Unable to locate"
2754 				" sense buffer for task with sense\n",
2755 				cmd->se_tfo->get_task_tag(cmd), task->task_no);
2756 			continue;
2757 		}
2758 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2759 
2760 		offset = cmd->se_tfo->set_fabric_sense_len(cmd,
2761 				TRANSPORT_SENSE_BUFFER);
2762 
2763 		memcpy(&buffer[offset], sense_buffer,
2764 				TRANSPORT_SENSE_BUFFER);
2765 		cmd->scsi_status = task->task_scsi_status;
2766 		/* Automatically padded */
2767 		cmd->scsi_sense_length =
2768 				(TRANSPORT_SENSE_BUFFER + offset);
2769 
2770 		pr_debug("HBA_[%u]_PLUG[%s]: Set SAM STATUS: 0x%02x"
2771 				" and sense\n",
2772 			dev->se_hba->hba_id, dev->transport->name,
2773 				cmd->scsi_status);
2774 		return 0;
2775 	}
2776 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2777 
2778 	return -1;
2779 }
2780 
2781 static int
2782 transport_handle_reservation_conflict(struct se_cmd *cmd)
2783 {
2784 	cmd->transport_wait_for_tasks = &transport_nop_wait_for_tasks;
2785 	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2786 	cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT;
2787 	cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
2788 	/*
2789 	 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
2790 	 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
2791 	 * CONFLICT STATUS.
2792 	 *
2793 	 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
2794 	 */
2795 	if (cmd->se_sess &&
2796 	    cmd->se_dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 2)
2797 		core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
2798 			cmd->orig_fe_lun, 0x2C,
2799 			ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
2800 	return -EINVAL;
2801 }
2802 
2803 static inline long long transport_dev_end_lba(struct se_device *dev)
2804 {
2805 	return dev->transport->get_blocks(dev) + 1;
2806 }
2807 
2808 static int transport_cmd_get_valid_sectors(struct se_cmd *cmd)
2809 {
2810 	struct se_device *dev = cmd->se_dev;
2811 	u32 sectors;
2812 
2813 	if (dev->transport->get_device_type(dev) != TYPE_DISK)
2814 		return 0;
2815 
2816 	sectors = (cmd->data_length / dev->se_sub_dev->se_dev_attrib.block_size);
2817 
2818 	if ((cmd->t_task_lba + sectors) > transport_dev_end_lba(dev)) {
2819 		pr_err("LBA: %llu Sectors: %u exceeds"
2820 			" transport_dev_end_lba(): %llu\n",
2821 			cmd->t_task_lba, sectors,
2822 			transport_dev_end_lba(dev));
2823 		pr_err("  We should return CHECK_CONDITION"
2824 		       " but we don't yet\n");
2825 		return 0;
2826 	}
2827 
2828 	return sectors;
2829 }
2830 
2831 /*	transport_generic_cmd_sequencer():
2832  *
2833  *	Generic Command Sequencer that should work for most DAS transport
2834  *	drivers.
2835  *
2836  *	Called from transport_generic_allocate_tasks() in the $FABRIC_MOD
2837  *	RX Thread.
2838  *
2839  *	FIXME: Need to support other SCSI OPCODES where as well.
2840  */
2841 static int transport_generic_cmd_sequencer(
2842 	struct se_cmd *cmd,
2843 	unsigned char *cdb)
2844 {
2845 	struct se_device *dev = cmd->se_dev;
2846 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
2847 	int ret = 0, sector_ret = 0, passthrough;
2848 	u32 sectors = 0, size = 0, pr_reg_type = 0;
2849 	u16 service_action;
2850 	u8 alua_ascq = 0;
2851 	/*
2852 	 * Check for an existing UNIT ATTENTION condition
2853 	 */
2854 	if (core_scsi3_ua_check(cmd, cdb) < 0) {
2855 		cmd->transport_wait_for_tasks =
2856 				&transport_nop_wait_for_tasks;
2857 		cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2858 		cmd->scsi_sense_reason = TCM_CHECK_CONDITION_UNIT_ATTENTION;
2859 		return -EINVAL;
2860 	}
2861 	/*
2862 	 * Check status of Asymmetric Logical Unit Assignment port
2863 	 */
2864 	ret = su_dev->t10_alua.alua_state_check(cmd, cdb, &alua_ascq);
2865 	if (ret != 0) {
2866 		cmd->transport_wait_for_tasks = &transport_nop_wait_for_tasks;
2867 		/*
2868 		 * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
2869 		 * The ALUA additional sense code qualifier (ASCQ) is determined
2870 		 * by the ALUA primary or secondary access state..
2871 		 */
2872 		if (ret > 0) {
2873 #if 0
2874 			pr_debug("[%s]: ALUA TG Port not available,"
2875 				" SenseKey: NOT_READY, ASC/ASCQ: 0x04/0x%02x\n",
2876 				cmd->se_tfo->get_fabric_name(), alua_ascq);
2877 #endif
2878 			transport_set_sense_codes(cmd, 0x04, alua_ascq);
2879 			cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2880 			cmd->scsi_sense_reason = TCM_CHECK_CONDITION_NOT_READY;
2881 			return -EINVAL;
2882 		}
2883 		goto out_invalid_cdb_field;
2884 	}
2885 	/*
2886 	 * Check status for SPC-3 Persistent Reservations
2887 	 */
2888 	if (su_dev->t10_pr.pr_ops.t10_reservation_check(cmd, &pr_reg_type) != 0) {
2889 		if (su_dev->t10_pr.pr_ops.t10_seq_non_holder(
2890 					cmd, cdb, pr_reg_type) != 0)
2891 			return transport_handle_reservation_conflict(cmd);
2892 		/*
2893 		 * This means the CDB is allowed for the SCSI Initiator port
2894 		 * when said port is *NOT* holding the legacy SPC-2 or
2895 		 * SPC-3 Persistent Reservation.
2896 		 */
2897 	}
2898 
2899 	switch (cdb[0]) {
2900 	case READ_6:
2901 		sectors = transport_get_sectors_6(cdb, cmd, &sector_ret);
2902 		if (sector_ret)
2903 			goto out_unsupported_cdb;
2904 		size = transport_get_size(sectors, cdb, cmd);
2905 		cmd->transport_split_cdb = &split_cdb_XX_6;
2906 		cmd->t_task_lba = transport_lba_21(cdb);
2907 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2908 		break;
2909 	case READ_10:
2910 		sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2911 		if (sector_ret)
2912 			goto out_unsupported_cdb;
2913 		size = transport_get_size(sectors, cdb, cmd);
2914 		cmd->transport_split_cdb = &split_cdb_XX_10;
2915 		cmd->t_task_lba = transport_lba_32(cdb);
2916 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2917 		break;
2918 	case READ_12:
2919 		sectors = transport_get_sectors_12(cdb, cmd, &sector_ret);
2920 		if (sector_ret)
2921 			goto out_unsupported_cdb;
2922 		size = transport_get_size(sectors, cdb, cmd);
2923 		cmd->transport_split_cdb = &split_cdb_XX_12;
2924 		cmd->t_task_lba = transport_lba_32(cdb);
2925 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2926 		break;
2927 	case READ_16:
2928 		sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2929 		if (sector_ret)
2930 			goto out_unsupported_cdb;
2931 		size = transport_get_size(sectors, cdb, cmd);
2932 		cmd->transport_split_cdb = &split_cdb_XX_16;
2933 		cmd->t_task_lba = transport_lba_64(cdb);
2934 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2935 		break;
2936 	case WRITE_6:
2937 		sectors = transport_get_sectors_6(cdb, cmd, &sector_ret);
2938 		if (sector_ret)
2939 			goto out_unsupported_cdb;
2940 		size = transport_get_size(sectors, cdb, cmd);
2941 		cmd->transport_split_cdb = &split_cdb_XX_6;
2942 		cmd->t_task_lba = transport_lba_21(cdb);
2943 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2944 		break;
2945 	case WRITE_10:
2946 		sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2947 		if (sector_ret)
2948 			goto out_unsupported_cdb;
2949 		size = transport_get_size(sectors, cdb, cmd);
2950 		cmd->transport_split_cdb = &split_cdb_XX_10;
2951 		cmd->t_task_lba = transport_lba_32(cdb);
2952 		cmd->t_tasks_fua = (cdb[1] & 0x8);
2953 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2954 		break;
2955 	case WRITE_12:
2956 		sectors = transport_get_sectors_12(cdb, cmd, &sector_ret);
2957 		if (sector_ret)
2958 			goto out_unsupported_cdb;
2959 		size = transport_get_size(sectors, cdb, cmd);
2960 		cmd->transport_split_cdb = &split_cdb_XX_12;
2961 		cmd->t_task_lba = transport_lba_32(cdb);
2962 		cmd->t_tasks_fua = (cdb[1] & 0x8);
2963 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2964 		break;
2965 	case WRITE_16:
2966 		sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2967 		if (sector_ret)
2968 			goto out_unsupported_cdb;
2969 		size = transport_get_size(sectors, cdb, cmd);
2970 		cmd->transport_split_cdb = &split_cdb_XX_16;
2971 		cmd->t_task_lba = transport_lba_64(cdb);
2972 		cmd->t_tasks_fua = (cdb[1] & 0x8);
2973 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2974 		break;
2975 	case XDWRITEREAD_10:
2976 		if ((cmd->data_direction != DMA_TO_DEVICE) ||
2977 		    !(cmd->t_tasks_bidi))
2978 			goto out_invalid_cdb_field;
2979 		sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2980 		if (sector_ret)
2981 			goto out_unsupported_cdb;
2982 		size = transport_get_size(sectors, cdb, cmd);
2983 		cmd->transport_split_cdb = &split_cdb_XX_10;
2984 		cmd->t_task_lba = transport_lba_32(cdb);
2985 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2986 		passthrough = (dev->transport->transport_type ==
2987 				TRANSPORT_PLUGIN_PHBA_PDEV);
2988 		/*
2989 		 * Skip the remaining assignments for TCM/PSCSI passthrough
2990 		 */
2991 		if (passthrough)
2992 			break;
2993 		/*
2994 		 * Setup BIDI XOR callback to be run during transport_generic_complete_ok()
2995 		 */
2996 		cmd->transport_complete_callback = &transport_xor_callback;
2997 		cmd->t_tasks_fua = (cdb[1] & 0x8);
2998 		break;
2999 	case VARIABLE_LENGTH_CMD:
3000 		service_action = get_unaligned_be16(&cdb[8]);
3001 		/*
3002 		 * Determine if this is TCM/PSCSI device and we should disable
3003 		 * internal emulation for this CDB.
3004 		 */
3005 		passthrough = (dev->transport->transport_type ==
3006 					TRANSPORT_PLUGIN_PHBA_PDEV);
3007 
3008 		switch (service_action) {
3009 		case XDWRITEREAD_32:
3010 			sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
3011 			if (sector_ret)
3012 				goto out_unsupported_cdb;
3013 			size = transport_get_size(sectors, cdb, cmd);
3014 			/*
3015 			 * Use WRITE_32 and READ_32 opcodes for the emulated
3016 			 * XDWRITE_READ_32 logic.
3017 			 */
3018 			cmd->transport_split_cdb = &split_cdb_XX_32;
3019 			cmd->t_task_lba = transport_lba_64_ext(cdb);
3020 			cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
3021 
3022 			/*
3023 			 * Skip the remaining assignments for TCM/PSCSI passthrough
3024 			 */
3025 			if (passthrough)
3026 				break;
3027 
3028 			/*
3029 			 * Setup BIDI XOR callback to be run during
3030 			 * transport_generic_complete_ok()
3031 			 */
3032 			cmd->transport_complete_callback = &transport_xor_callback;
3033 			cmd->t_tasks_fua = (cdb[10] & 0x8);
3034 			break;
3035 		case WRITE_SAME_32:
3036 			sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
3037 			if (sector_ret)
3038 				goto out_unsupported_cdb;
3039 
3040 			if (sectors)
3041 				size = transport_get_size(sectors, cdb, cmd);
3042 			else {
3043 				pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
3044 				       " supported\n");
3045 				goto out_invalid_cdb_field;
3046 			}
3047 
3048 			cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
3049 			cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3050 
3051 			/*
3052 			 * Skip the remaining assignments for TCM/PSCSI passthrough
3053 			 */
3054 			if (passthrough)
3055 				break;
3056 
3057 			if ((cdb[10] & 0x04) || (cdb[10] & 0x02)) {
3058 				pr_err("WRITE_SAME PBDATA and LBDATA"
3059 					" bits not supported for Block Discard"
3060 					" Emulation\n");
3061 				goto out_invalid_cdb_field;
3062 			}
3063 			/*
3064 			 * Currently for the emulated case we only accept
3065 			 * tpws with the UNMAP=1 bit set.
3066 			 */
3067 			if (!(cdb[10] & 0x08)) {
3068 				pr_err("WRITE_SAME w/o UNMAP bit not"
3069 					" supported for Block Discard Emulation\n");
3070 				goto out_invalid_cdb_field;
3071 			}
3072 			break;
3073 		default:
3074 			pr_err("VARIABLE_LENGTH_CMD service action"
3075 				" 0x%04x not supported\n", service_action);
3076 			goto out_unsupported_cdb;
3077 		}
3078 		break;
3079 	case MAINTENANCE_IN:
3080 		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
3081 			/* MAINTENANCE_IN from SCC-2 */
3082 			/*
3083 			 * Check for emulated MI_REPORT_TARGET_PGS.
3084 			 */
3085 			if (cdb[1] == MI_REPORT_TARGET_PGS) {
3086 				cmd->transport_emulate_cdb =
3087 				(su_dev->t10_alua.alua_type ==
3088 				 SPC3_ALUA_EMULATED) ?
3089 				core_emulate_report_target_port_groups :
3090 				NULL;
3091 			}
3092 			size = (cdb[6] << 24) | (cdb[7] << 16) |
3093 			       (cdb[8] << 8) | cdb[9];
3094 		} else {
3095 			/* GPCMD_SEND_KEY from multi media commands */
3096 			size = (cdb[8] << 8) + cdb[9];
3097 		}
3098 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3099 		break;
3100 	case MODE_SELECT:
3101 		size = cdb[4];
3102 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3103 		break;
3104 	case MODE_SELECT_10:
3105 		size = (cdb[7] << 8) + cdb[8];
3106 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3107 		break;
3108 	case MODE_SENSE:
3109 		size = cdb[4];
3110 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3111 		break;
3112 	case MODE_SENSE_10:
3113 	case GPCMD_READ_BUFFER_CAPACITY:
3114 	case GPCMD_SEND_OPC:
3115 	case LOG_SELECT:
3116 	case LOG_SENSE:
3117 		size = (cdb[7] << 8) + cdb[8];
3118 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3119 		break;
3120 	case READ_BLOCK_LIMITS:
3121 		size = READ_BLOCK_LEN;
3122 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3123 		break;
3124 	case GPCMD_GET_CONFIGURATION:
3125 	case GPCMD_READ_FORMAT_CAPACITIES:
3126 	case GPCMD_READ_DISC_INFO:
3127 	case GPCMD_READ_TRACK_RZONE_INFO:
3128 		size = (cdb[7] << 8) + cdb[8];
3129 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3130 		break;
3131 	case PERSISTENT_RESERVE_IN:
3132 	case PERSISTENT_RESERVE_OUT:
3133 		cmd->transport_emulate_cdb =
3134 			(su_dev->t10_pr.res_type ==
3135 			 SPC3_PERSISTENT_RESERVATIONS) ?
3136 			core_scsi3_emulate_pr : NULL;
3137 		size = (cdb[7] << 8) + cdb[8];
3138 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3139 		break;
3140 	case GPCMD_MECHANISM_STATUS:
3141 	case GPCMD_READ_DVD_STRUCTURE:
3142 		size = (cdb[8] << 8) + cdb[9];
3143 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3144 		break;
3145 	case READ_POSITION:
3146 		size = READ_POSITION_LEN;
3147 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3148 		break;
3149 	case MAINTENANCE_OUT:
3150 		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
3151 			/* MAINTENANCE_OUT from SCC-2
3152 			 *
3153 			 * Check for emulated MO_SET_TARGET_PGS.
3154 			 */
3155 			if (cdb[1] == MO_SET_TARGET_PGS) {
3156 				cmd->transport_emulate_cdb =
3157 				(su_dev->t10_alua.alua_type ==
3158 					SPC3_ALUA_EMULATED) ?
3159 				core_emulate_set_target_port_groups :
3160 				NULL;
3161 			}
3162 
3163 			size = (cdb[6] << 24) | (cdb[7] << 16) |
3164 			       (cdb[8] << 8) | cdb[9];
3165 		} else  {
3166 			/* GPCMD_REPORT_KEY from multi media commands */
3167 			size = (cdb[8] << 8) + cdb[9];
3168 		}
3169 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3170 		break;
3171 	case INQUIRY:
3172 		size = (cdb[3] << 8) + cdb[4];
3173 		/*
3174 		 * Do implict HEAD_OF_QUEUE processing for INQUIRY.
3175 		 * See spc4r17 section 5.3
3176 		 */
3177 		if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3178 			cmd->sam_task_attr = MSG_HEAD_TAG;
3179 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3180 		break;
3181 	case READ_BUFFER:
3182 		size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
3183 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3184 		break;
3185 	case READ_CAPACITY:
3186 		size = READ_CAP_LEN;
3187 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3188 		break;
3189 	case READ_MEDIA_SERIAL_NUMBER:
3190 	case SECURITY_PROTOCOL_IN:
3191 	case SECURITY_PROTOCOL_OUT:
3192 		size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
3193 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3194 		break;
3195 	case SERVICE_ACTION_IN:
3196 	case ACCESS_CONTROL_IN:
3197 	case ACCESS_CONTROL_OUT:
3198 	case EXTENDED_COPY:
3199 	case READ_ATTRIBUTE:
3200 	case RECEIVE_COPY_RESULTS:
3201 	case WRITE_ATTRIBUTE:
3202 		size = (cdb[10] << 24) | (cdb[11] << 16) |
3203 		       (cdb[12] << 8) | cdb[13];
3204 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3205 		break;
3206 	case RECEIVE_DIAGNOSTIC:
3207 	case SEND_DIAGNOSTIC:
3208 		size = (cdb[3] << 8) | cdb[4];
3209 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3210 		break;
3211 /* #warning FIXME: Figure out correct GPCMD_READ_CD blocksize. */
3212 #if 0
3213 	case GPCMD_READ_CD:
3214 		sectors = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
3215 		size = (2336 * sectors);
3216 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3217 		break;
3218 #endif
3219 	case READ_TOC:
3220 		size = cdb[8];
3221 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3222 		break;
3223 	case REQUEST_SENSE:
3224 		size = cdb[4];
3225 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3226 		break;
3227 	case READ_ELEMENT_STATUS:
3228 		size = 65536 * cdb[7] + 256 * cdb[8] + cdb[9];
3229 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3230 		break;
3231 	case WRITE_BUFFER:
3232 		size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
3233 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3234 		break;
3235 	case RESERVE:
3236 	case RESERVE_10:
3237 		/*
3238 		 * The SPC-2 RESERVE does not contain a size in the SCSI CDB.
3239 		 * Assume the passthrough or $FABRIC_MOD will tell us about it.
3240 		 */
3241 		if (cdb[0] == RESERVE_10)
3242 			size = (cdb[7] << 8) | cdb[8];
3243 		else
3244 			size = cmd->data_length;
3245 
3246 		/*
3247 		 * Setup the legacy emulated handler for SPC-2 and
3248 		 * >= SPC-3 compatible reservation handling (CRH=1)
3249 		 * Otherwise, we assume the underlying SCSI logic is
3250 		 * is running in SPC_PASSTHROUGH, and wants reservations
3251 		 * emulation disabled.
3252 		 */
3253 		cmd->transport_emulate_cdb =
3254 				(su_dev->t10_pr.res_type !=
3255 				 SPC_PASSTHROUGH) ?
3256 				core_scsi2_emulate_crh : NULL;
3257 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3258 		break;
3259 	case RELEASE:
3260 	case RELEASE_10:
3261 		/*
3262 		 * The SPC-2 RELEASE does not contain a size in the SCSI CDB.
3263 		 * Assume the passthrough or $FABRIC_MOD will tell us about it.
3264 		*/
3265 		if (cdb[0] == RELEASE_10)
3266 			size = (cdb[7] << 8) | cdb[8];
3267 		else
3268 			size = cmd->data_length;
3269 
3270 		cmd->transport_emulate_cdb =
3271 				(su_dev->t10_pr.res_type !=
3272 				 SPC_PASSTHROUGH) ?
3273 				core_scsi2_emulate_crh : NULL;
3274 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3275 		break;
3276 	case SYNCHRONIZE_CACHE:
3277 	case 0x91: /* SYNCHRONIZE_CACHE_16: */
3278 		/*
3279 		 * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
3280 		 */
3281 		if (cdb[0] == SYNCHRONIZE_CACHE) {
3282 			sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
3283 			cmd->t_task_lba = transport_lba_32(cdb);
3284 		} else {
3285 			sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
3286 			cmd->t_task_lba = transport_lba_64(cdb);
3287 		}
3288 		if (sector_ret)
3289 			goto out_unsupported_cdb;
3290 
3291 		size = transport_get_size(sectors, cdb, cmd);
3292 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3293 
3294 		/*
3295 		 * For TCM/pSCSI passthrough, skip cmd->transport_emulate_cdb()
3296 		 */
3297 		if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
3298 			break;
3299 		/*
3300 		 * Set SCF_EMULATE_CDB_ASYNC to ensure asynchronous operation
3301 		 * for SYNCHRONIZE_CACHE* Immed=1 case in __transport_execute_tasks()
3302 		 */
3303 		cmd->se_cmd_flags |= SCF_EMULATE_CDB_ASYNC;
3304 		/*
3305 		 * Check to ensure that LBA + Range does not exceed past end of
3306 		 * device.
3307 		 */
3308 		if (!transport_cmd_get_valid_sectors(cmd))
3309 			goto out_invalid_cdb_field;
3310 		break;
3311 	case UNMAP:
3312 		size = get_unaligned_be16(&cdb[7]);
3313 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3314 		break;
3315 	case WRITE_SAME_16:
3316 		sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
3317 		if (sector_ret)
3318 			goto out_unsupported_cdb;
3319 
3320 		if (sectors)
3321 			size = transport_get_size(sectors, cdb, cmd);
3322 		else {
3323 			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
3324 			goto out_invalid_cdb_field;
3325 		}
3326 
3327 		cmd->t_task_lba = get_unaligned_be16(&cdb[2]);
3328 		passthrough = (dev->transport->transport_type ==
3329 				TRANSPORT_PLUGIN_PHBA_PDEV);
3330 		/*
3331 		 * Determine if the received WRITE_SAME_16 is used to for direct
3332 		 * passthrough into Linux/SCSI with struct request via TCM/pSCSI
3333 		 * or we are signaling the use of internal WRITE_SAME + UNMAP=1
3334 		 * emulation for -> Linux/BLOCK disbard with TCM/IBLOCK and
3335 		 * TCM/FILEIO subsystem plugin backstores.
3336 		 */
3337 		if (!passthrough) {
3338 			if ((cdb[1] & 0x04) || (cdb[1] & 0x02)) {
3339 				pr_err("WRITE_SAME PBDATA and LBDATA"
3340 					" bits not supported for Block Discard"
3341 					" Emulation\n");
3342 				goto out_invalid_cdb_field;
3343 			}
3344 			/*
3345 			 * Currently for the emulated case we only accept
3346 			 * tpws with the UNMAP=1 bit set.
3347 			 */
3348 			if (!(cdb[1] & 0x08)) {
3349 				pr_err("WRITE_SAME w/o UNMAP bit not "
3350 					" supported for Block Discard Emulation\n");
3351 				goto out_invalid_cdb_field;
3352 			}
3353 		}
3354 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3355 		break;
3356 	case ALLOW_MEDIUM_REMOVAL:
3357 	case GPCMD_CLOSE_TRACK:
3358 	case ERASE:
3359 	case INITIALIZE_ELEMENT_STATUS:
3360 	case GPCMD_LOAD_UNLOAD:
3361 	case REZERO_UNIT:
3362 	case SEEK_10:
3363 	case GPCMD_SET_SPEED:
3364 	case SPACE:
3365 	case START_STOP:
3366 	case TEST_UNIT_READY:
3367 	case VERIFY:
3368 	case WRITE_FILEMARKS:
3369 	case MOVE_MEDIUM:
3370 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3371 		break;
3372 	case REPORT_LUNS:
3373 		cmd->transport_emulate_cdb =
3374 				transport_core_report_lun_response;
3375 		size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
3376 		/*
3377 		 * Do implict HEAD_OF_QUEUE processing for REPORT_LUNS
3378 		 * See spc4r17 section 5.3
3379 		 */
3380 		if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3381 			cmd->sam_task_attr = MSG_HEAD_TAG;
3382 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3383 		break;
3384 	default:
3385 		pr_warn("TARGET_CORE[%s]: Unsupported SCSI Opcode"
3386 			" 0x%02x, sending CHECK_CONDITION.\n",
3387 			cmd->se_tfo->get_fabric_name(), cdb[0]);
3388 		cmd->transport_wait_for_tasks = &transport_nop_wait_for_tasks;
3389 		goto out_unsupported_cdb;
3390 	}
3391 
3392 	if (size != cmd->data_length) {
3393 		pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
3394 			" %u does not match SCSI CDB Length: %u for SAM Opcode:"
3395 			" 0x%02x\n", cmd->se_tfo->get_fabric_name(),
3396 				cmd->data_length, size, cdb[0]);
3397 
3398 		cmd->cmd_spdtl = size;
3399 
3400 		if (cmd->data_direction == DMA_TO_DEVICE) {
3401 			pr_err("Rejecting underflow/overflow"
3402 					" WRITE data\n");
3403 			goto out_invalid_cdb_field;
3404 		}
3405 		/*
3406 		 * Reject READ_* or WRITE_* with overflow/underflow for
3407 		 * type SCF_SCSI_DATA_SG_IO_CDB.
3408 		 */
3409 		if (!ret && (dev->se_sub_dev->se_dev_attrib.block_size != 512))  {
3410 			pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
3411 				" CDB on non 512-byte sector setup subsystem"
3412 				" plugin: %s\n", dev->transport->name);
3413 			/* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
3414 			goto out_invalid_cdb_field;
3415 		}
3416 
3417 		if (size > cmd->data_length) {
3418 			cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
3419 			cmd->residual_count = (size - cmd->data_length);
3420 		} else {
3421 			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
3422 			cmd->residual_count = (cmd->data_length - size);
3423 		}
3424 		cmd->data_length = size;
3425 	}
3426 
3427 	/* Let's limit control cdbs to a page, for simplicity's sake. */
3428 	if ((cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) &&
3429 	    size > PAGE_SIZE)
3430 		goto out_invalid_cdb_field;
3431 
3432 	transport_set_supported_SAM_opcode(cmd);
3433 	return ret;
3434 
3435 out_unsupported_cdb:
3436 	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3437 	cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
3438 	return -EINVAL;
3439 out_invalid_cdb_field:
3440 	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3441 	cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3442 	return -EINVAL;
3443 }
3444 
3445 /*
3446  * Called from transport_generic_complete_ok() and
3447  * transport_generic_request_failure() to determine which dormant/delayed
3448  * and ordered cmds need to have their tasks added to the execution queue.
3449  */
3450 static void transport_complete_task_attr(struct se_cmd *cmd)
3451 {
3452 	struct se_device *dev = cmd->se_dev;
3453 	struct se_cmd *cmd_p, *cmd_tmp;
3454 	int new_active_tasks = 0;
3455 
3456 	if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
3457 		atomic_dec(&dev->simple_cmds);
3458 		smp_mb__after_atomic_dec();
3459 		dev->dev_cur_ordered_id++;
3460 		pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
3461 			" SIMPLE: %u\n", dev->dev_cur_ordered_id,
3462 			cmd->se_ordered_id);
3463 	} else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
3464 		atomic_dec(&dev->dev_hoq_count);
3465 		smp_mb__after_atomic_dec();
3466 		dev->dev_cur_ordered_id++;
3467 		pr_debug("Incremented dev_cur_ordered_id: %u for"
3468 			" HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
3469 			cmd->se_ordered_id);
3470 	} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
3471 		spin_lock(&dev->ordered_cmd_lock);
3472 		list_del(&cmd->se_ordered_node);
3473 		atomic_dec(&dev->dev_ordered_sync);
3474 		smp_mb__after_atomic_dec();
3475 		spin_unlock(&dev->ordered_cmd_lock);
3476 
3477 		dev->dev_cur_ordered_id++;
3478 		pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
3479 			" %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
3480 	}
3481 	/*
3482 	 * Process all commands up to the last received
3483 	 * ORDERED task attribute which requires another blocking
3484 	 * boundary
3485 	 */
3486 	spin_lock(&dev->delayed_cmd_lock);
3487 	list_for_each_entry_safe(cmd_p, cmd_tmp,
3488 			&dev->delayed_cmd_list, se_delayed_node) {
3489 
3490 		list_del(&cmd_p->se_delayed_node);
3491 		spin_unlock(&dev->delayed_cmd_lock);
3492 
3493 		pr_debug("Calling add_tasks() for"
3494 			" cmd_p: 0x%02x Task Attr: 0x%02x"
3495 			" Dormant -> Active, se_ordered_id: %u\n",
3496 			cmd_p->t_task_cdb[0],
3497 			cmd_p->sam_task_attr, cmd_p->se_ordered_id);
3498 
3499 		transport_add_tasks_from_cmd(cmd_p);
3500 		new_active_tasks++;
3501 
3502 		spin_lock(&dev->delayed_cmd_lock);
3503 		if (cmd_p->sam_task_attr == MSG_ORDERED_TAG)
3504 			break;
3505 	}
3506 	spin_unlock(&dev->delayed_cmd_lock);
3507 	/*
3508 	 * If new tasks have become active, wake up the transport thread
3509 	 * to do the processing of the Active tasks.
3510 	 */
3511 	if (new_active_tasks != 0)
3512 		wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
3513 }
3514 
3515 static int transport_complete_qf(struct se_cmd *cmd)
3516 {
3517 	int ret = 0;
3518 
3519 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
3520 		return cmd->se_tfo->queue_status(cmd);
3521 
3522 	switch (cmd->data_direction) {
3523 	case DMA_FROM_DEVICE:
3524 		ret = cmd->se_tfo->queue_data_in(cmd);
3525 		break;
3526 	case DMA_TO_DEVICE:
3527 		if (cmd->t_bidi_data_sg) {
3528 			ret = cmd->se_tfo->queue_data_in(cmd);
3529 			if (ret < 0)
3530 				return ret;
3531 		}
3532 		/* Fall through for DMA_TO_DEVICE */
3533 	case DMA_NONE:
3534 		ret = cmd->se_tfo->queue_status(cmd);
3535 		break;
3536 	default:
3537 		break;
3538 	}
3539 
3540 	return ret;
3541 }
3542 
3543 static void transport_handle_queue_full(
3544 	struct se_cmd *cmd,
3545 	struct se_device *dev,
3546 	int (*qf_callback)(struct se_cmd *))
3547 {
3548 	spin_lock_irq(&dev->qf_cmd_lock);
3549 	cmd->se_cmd_flags |= SCF_EMULATE_QUEUE_FULL;
3550 	cmd->transport_qf_callback = qf_callback;
3551 	list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
3552 	atomic_inc(&dev->dev_qf_count);
3553 	smp_mb__after_atomic_inc();
3554 	spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
3555 
3556 	schedule_work(&cmd->se_dev->qf_work_queue);
3557 }
3558 
3559 static void transport_generic_complete_ok(struct se_cmd *cmd)
3560 {
3561 	int reason = 0, ret;
3562 	/*
3563 	 * Check if we need to move delayed/dormant tasks from cmds on the
3564 	 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
3565 	 * Attribute.
3566 	 */
3567 	if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3568 		transport_complete_task_attr(cmd);
3569 	/*
3570 	 * Check to schedule QUEUE_FULL work, or execute an existing
3571 	 * cmd->transport_qf_callback()
3572 	 */
3573 	if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
3574 		schedule_work(&cmd->se_dev->qf_work_queue);
3575 
3576 	if (cmd->transport_qf_callback) {
3577 		ret = cmd->transport_qf_callback(cmd);
3578 		if (ret < 0)
3579 			goto queue_full;
3580 
3581 		cmd->transport_qf_callback = NULL;
3582 		goto done;
3583 	}
3584 	/*
3585 	 * Check if we need to retrieve a sense buffer from
3586 	 * the struct se_cmd in question.
3587 	 */
3588 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
3589 		if (transport_get_sense_data(cmd) < 0)
3590 			reason = TCM_NON_EXISTENT_LUN;
3591 
3592 		/*
3593 		 * Only set when an struct se_task->task_scsi_status returned
3594 		 * a non GOOD status.
3595 		 */
3596 		if (cmd->scsi_status) {
3597 			ret = transport_send_check_condition_and_sense(
3598 					cmd, reason, 1);
3599 			if (ret == -EAGAIN)
3600 				goto queue_full;
3601 
3602 			transport_lun_remove_cmd(cmd);
3603 			transport_cmd_check_stop_to_fabric(cmd);
3604 			return;
3605 		}
3606 	}
3607 	/*
3608 	 * Check for a callback, used by amongst other things
3609 	 * XDWRITE_READ_10 emulation.
3610 	 */
3611 	if (cmd->transport_complete_callback)
3612 		cmd->transport_complete_callback(cmd);
3613 
3614 	switch (cmd->data_direction) {
3615 	case DMA_FROM_DEVICE:
3616 		spin_lock(&cmd->se_lun->lun_sep_lock);
3617 		if (cmd->se_lun->lun_sep) {
3618 			cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
3619 					cmd->data_length;
3620 		}
3621 		spin_unlock(&cmd->se_lun->lun_sep_lock);
3622 
3623 		ret = cmd->se_tfo->queue_data_in(cmd);
3624 		if (ret == -EAGAIN)
3625 			goto queue_full;
3626 		break;
3627 	case DMA_TO_DEVICE:
3628 		spin_lock(&cmd->se_lun->lun_sep_lock);
3629 		if (cmd->se_lun->lun_sep) {
3630 			cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
3631 				cmd->data_length;
3632 		}
3633 		spin_unlock(&cmd->se_lun->lun_sep_lock);
3634 		/*
3635 		 * Check if we need to send READ payload for BIDI-COMMAND
3636 		 */
3637 		if (cmd->t_bidi_data_sg) {
3638 			spin_lock(&cmd->se_lun->lun_sep_lock);
3639 			if (cmd->se_lun->lun_sep) {
3640 				cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
3641 					cmd->data_length;
3642 			}
3643 			spin_unlock(&cmd->se_lun->lun_sep_lock);
3644 			ret = cmd->se_tfo->queue_data_in(cmd);
3645 			if (ret == -EAGAIN)
3646 				goto queue_full;
3647 			break;
3648 		}
3649 		/* Fall through for DMA_TO_DEVICE */
3650 	case DMA_NONE:
3651 		ret = cmd->se_tfo->queue_status(cmd);
3652 		if (ret == -EAGAIN)
3653 			goto queue_full;
3654 		break;
3655 	default:
3656 		break;
3657 	}
3658 
3659 done:
3660 	transport_lun_remove_cmd(cmd);
3661 	transport_cmd_check_stop_to_fabric(cmd);
3662 	return;
3663 
3664 queue_full:
3665 	pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
3666 		" data_direction: %d\n", cmd, cmd->data_direction);
3667 	transport_handle_queue_full(cmd, cmd->se_dev, transport_complete_qf);
3668 }
3669 
3670 static void transport_free_dev_tasks(struct se_cmd *cmd)
3671 {
3672 	struct se_task *task, *task_tmp;
3673 	unsigned long flags;
3674 
3675 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3676 	list_for_each_entry_safe(task, task_tmp,
3677 				&cmd->t_task_list, t_list) {
3678 		if (atomic_read(&task->task_active))
3679 			continue;
3680 
3681 		kfree(task->task_sg_bidi);
3682 		kfree(task->task_sg);
3683 
3684 		list_del(&task->t_list);
3685 
3686 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3687 		if (task->se_dev)
3688 			task->se_dev->transport->free_task(task);
3689 		else
3690 			pr_err("task[%u] - task->se_dev is NULL\n",
3691 				task->task_no);
3692 		spin_lock_irqsave(&cmd->t_state_lock, flags);
3693 	}
3694 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3695 }
3696 
3697 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
3698 {
3699 	struct scatterlist *sg;
3700 	int count;
3701 
3702 	for_each_sg(sgl, sg, nents, count)
3703 		__free_page(sg_page(sg));
3704 
3705 	kfree(sgl);
3706 }
3707 
3708 static inline void transport_free_pages(struct se_cmd *cmd)
3709 {
3710 	if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
3711 		return;
3712 
3713 	transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
3714 	cmd->t_data_sg = NULL;
3715 	cmd->t_data_nents = 0;
3716 
3717 	transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
3718 	cmd->t_bidi_data_sg = NULL;
3719 	cmd->t_bidi_data_nents = 0;
3720 }
3721 
3722 static inline void transport_release_tasks(struct se_cmd *cmd)
3723 {
3724 	transport_free_dev_tasks(cmd);
3725 }
3726 
3727 static inline int transport_dec_and_check(struct se_cmd *cmd)
3728 {
3729 	unsigned long flags;
3730 
3731 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3732 	if (atomic_read(&cmd->t_fe_count)) {
3733 		if (!atomic_dec_and_test(&cmd->t_fe_count)) {
3734 			spin_unlock_irqrestore(&cmd->t_state_lock,
3735 					flags);
3736 			return 1;
3737 		}
3738 	}
3739 
3740 	if (atomic_read(&cmd->t_se_count)) {
3741 		if (!atomic_dec_and_test(&cmd->t_se_count)) {
3742 			spin_unlock_irqrestore(&cmd->t_state_lock,
3743 					flags);
3744 			return 1;
3745 		}
3746 	}
3747 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3748 
3749 	return 0;
3750 }
3751 
3752 static void transport_release_fe_cmd(struct se_cmd *cmd)
3753 {
3754 	unsigned long flags;
3755 
3756 	if (transport_dec_and_check(cmd))
3757 		return;
3758 
3759 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3760 	if (!atomic_read(&cmd->transport_dev_active)) {
3761 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3762 		goto free_pages;
3763 	}
3764 	atomic_set(&cmd->transport_dev_active, 0);
3765 	transport_all_task_dev_remove_state(cmd);
3766 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3767 
3768 	transport_release_tasks(cmd);
3769 free_pages:
3770 	transport_free_pages(cmd);
3771 	transport_free_se_cmd(cmd);
3772 	cmd->se_tfo->release_cmd(cmd);
3773 }
3774 
3775 static int
3776 transport_generic_remove(struct se_cmd *cmd, int session_reinstatement)
3777 {
3778 	unsigned long flags;
3779 
3780 	if (transport_dec_and_check(cmd)) {
3781 		if (session_reinstatement) {
3782 			spin_lock_irqsave(&cmd->t_state_lock, flags);
3783 			transport_all_task_dev_remove_state(cmd);
3784 			spin_unlock_irqrestore(&cmd->t_state_lock,
3785 					flags);
3786 		}
3787 		return 1;
3788 	}
3789 
3790 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3791 	if (!atomic_read(&cmd->transport_dev_active)) {
3792 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3793 		goto free_pages;
3794 	}
3795 	atomic_set(&cmd->transport_dev_active, 0);
3796 	transport_all_task_dev_remove_state(cmd);
3797 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3798 
3799 	transport_release_tasks(cmd);
3800 
3801 free_pages:
3802 	transport_free_pages(cmd);
3803 	transport_release_cmd(cmd);
3804 	return 0;
3805 }
3806 
3807 /*
3808  * transport_generic_map_mem_to_cmd - Use fabric-alloced pages instead of
3809  * allocating in the core.
3810  * @cmd:  Associated se_cmd descriptor
3811  * @mem:  SGL style memory for TCM WRITE / READ
3812  * @sg_mem_num: Number of SGL elements
3813  * @mem_bidi_in: SGL style memory for TCM BIDI READ
3814  * @sg_mem_bidi_num: Number of BIDI READ SGL elements
3815  *
3816  * Return: nonzero return cmd was rejected for -ENOMEM or inproper usage
3817  * of parameters.
3818  */
3819 int transport_generic_map_mem_to_cmd(
3820 	struct se_cmd *cmd,
3821 	struct scatterlist *sgl,
3822 	u32 sgl_count,
3823 	struct scatterlist *sgl_bidi,
3824 	u32 sgl_bidi_count)
3825 {
3826 	if (!sgl || !sgl_count)
3827 		return 0;
3828 
3829 	if ((cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) ||
3830 	    (cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB)) {
3831 
3832 		cmd->t_data_sg = sgl;
3833 		cmd->t_data_nents = sgl_count;
3834 
3835 		if (sgl_bidi && sgl_bidi_count) {
3836 			cmd->t_bidi_data_sg = sgl_bidi;
3837 			cmd->t_bidi_data_nents = sgl_bidi_count;
3838 		}
3839 		cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
3840 	}
3841 
3842 	return 0;
3843 }
3844 EXPORT_SYMBOL(transport_generic_map_mem_to_cmd);
3845 
3846 static int transport_new_cmd_obj(struct se_cmd *cmd)
3847 {
3848 	struct se_device *dev = cmd->se_dev;
3849 	u32 task_cdbs;
3850 	u32 rc;
3851 	int set_counts = 1;
3852 
3853 	/*
3854 	 * Setup any BIDI READ tasks and memory from
3855 	 * cmd->t_mem_bidi_list so the READ struct se_tasks
3856 	 * are queued first for the non pSCSI passthrough case.
3857 	 */
3858 	if (cmd->t_bidi_data_sg &&
3859 	    (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV)) {
3860 		rc = transport_allocate_tasks(cmd,
3861 					      cmd->t_task_lba,
3862 					      DMA_FROM_DEVICE,
3863 					      cmd->t_bidi_data_sg,
3864 					      cmd->t_bidi_data_nents);
3865 		if (rc <= 0) {
3866 			cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3867 			cmd->scsi_sense_reason =
3868 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3869 			return PYX_TRANSPORT_LU_COMM_FAILURE;
3870 		}
3871 		atomic_inc(&cmd->t_fe_count);
3872 		atomic_inc(&cmd->t_se_count);
3873 		set_counts = 0;
3874 	}
3875 	/*
3876 	 * Setup the tasks and memory from cmd->t_mem_list
3877 	 * Note for BIDI transfers this will contain the WRITE payload
3878 	 */
3879 	task_cdbs = transport_allocate_tasks(cmd,
3880 					     cmd->t_task_lba,
3881 					     cmd->data_direction,
3882 					     cmd->t_data_sg,
3883 					     cmd->t_data_nents);
3884 	if (task_cdbs <= 0) {
3885 		cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3886 		cmd->scsi_sense_reason =
3887 			TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3888 		return PYX_TRANSPORT_LU_COMM_FAILURE;
3889 	}
3890 
3891 	if (set_counts) {
3892 		atomic_inc(&cmd->t_fe_count);
3893 		atomic_inc(&cmd->t_se_count);
3894 	}
3895 
3896 	cmd->t_task_list_num = task_cdbs;
3897 
3898 	atomic_set(&cmd->t_task_cdbs_left, task_cdbs);
3899 	atomic_set(&cmd->t_task_cdbs_ex_left, task_cdbs);
3900 	atomic_set(&cmd->t_task_cdbs_timeout_left, task_cdbs);
3901 	return 0;
3902 }
3903 
3904 void *transport_kmap_first_data_page(struct se_cmd *cmd)
3905 {
3906 	struct scatterlist *sg = cmd->t_data_sg;
3907 
3908 	BUG_ON(!sg);
3909 	/*
3910 	 * We need to take into account a possible offset here for fabrics like
3911 	 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
3912 	 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
3913 	 */
3914 	return kmap(sg_page(sg)) + sg->offset;
3915 }
3916 EXPORT_SYMBOL(transport_kmap_first_data_page);
3917 
3918 void transport_kunmap_first_data_page(struct se_cmd *cmd)
3919 {
3920 	kunmap(sg_page(cmd->t_data_sg));
3921 }
3922 EXPORT_SYMBOL(transport_kunmap_first_data_page);
3923 
3924 static int
3925 transport_generic_get_mem(struct se_cmd *cmd)
3926 {
3927 	u32 length = cmd->data_length;
3928 	unsigned int nents;
3929 	struct page *page;
3930 	int i = 0;
3931 
3932 	nents = DIV_ROUND_UP(length, PAGE_SIZE);
3933 	cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
3934 	if (!cmd->t_data_sg)
3935 		return -ENOMEM;
3936 
3937 	cmd->t_data_nents = nents;
3938 	sg_init_table(cmd->t_data_sg, nents);
3939 
3940 	while (length) {
3941 		u32 page_len = min_t(u32, length, PAGE_SIZE);
3942 		page = alloc_page(GFP_KERNEL | __GFP_ZERO);
3943 		if (!page)
3944 			goto out;
3945 
3946 		sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
3947 		length -= page_len;
3948 		i++;
3949 	}
3950 	return 0;
3951 
3952 out:
3953 	while (i >= 0) {
3954 		__free_page(sg_page(&cmd->t_data_sg[i]));
3955 		i--;
3956 	}
3957 	kfree(cmd->t_data_sg);
3958 	cmd->t_data_sg = NULL;
3959 	return -ENOMEM;
3960 }
3961 
3962 /* Reduce sectors if they are too long for the device */
3963 static inline sector_t transport_limit_task_sectors(
3964 	struct se_device *dev,
3965 	unsigned long long lba,
3966 	sector_t sectors)
3967 {
3968 	sectors = min_t(sector_t, sectors, dev->se_sub_dev->se_dev_attrib.max_sectors);
3969 
3970 	if (dev->transport->get_device_type(dev) == TYPE_DISK)
3971 		if ((lba + sectors) > transport_dev_end_lba(dev))
3972 			sectors = ((transport_dev_end_lba(dev) - lba) + 1);
3973 
3974 	return sectors;
3975 }
3976 
3977 
3978 /*
3979  * This function can be used by HW target mode drivers to create a linked
3980  * scatterlist from all contiguously allocated struct se_task->task_sg[].
3981  * This is intended to be called during the completion path by TCM Core
3982  * when struct target_core_fabric_ops->check_task_sg_chaining is enabled.
3983  */
3984 void transport_do_task_sg_chain(struct se_cmd *cmd)
3985 {
3986 	struct scatterlist *sg_first = NULL;
3987 	struct scatterlist *sg_prev = NULL;
3988 	int sg_prev_nents = 0;
3989 	struct scatterlist *sg;
3990 	struct se_task *task;
3991 	u32 chained_nents = 0;
3992 	int i;
3993 
3994 	BUG_ON(!cmd->se_tfo->task_sg_chaining);
3995 
3996 	/*
3997 	 * Walk the struct se_task list and setup scatterlist chains
3998 	 * for each contiguously allocated struct se_task->task_sg[].
3999 	 */
4000 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
4001 		if (!task->task_sg)
4002 			continue;
4003 
4004 		BUG_ON(!task->task_padded_sg);
4005 
4006 		if (!sg_first) {
4007 			sg_first = task->task_sg;
4008 			chained_nents = task->task_sg_nents;
4009 		} else {
4010 			sg_chain(sg_prev, sg_prev_nents, task->task_sg);
4011 			chained_nents += task->task_sg_nents;
4012 		}
4013 
4014 		sg_prev = task->task_sg;
4015 		sg_prev_nents = task->task_sg_nents;
4016 	}
4017 	/*
4018 	 * Setup the starting pointer and total t_tasks_sg_linked_no including
4019 	 * padding SGs for linking and to mark the end.
4020 	 */
4021 	cmd->t_tasks_sg_chained = sg_first;
4022 	cmd->t_tasks_sg_chained_no = chained_nents;
4023 
4024 	pr_debug("Setup cmd: %p cmd->t_tasks_sg_chained: %p and"
4025 		" t_tasks_sg_chained_no: %u\n", cmd, cmd->t_tasks_sg_chained,
4026 		cmd->t_tasks_sg_chained_no);
4027 
4028 	for_each_sg(cmd->t_tasks_sg_chained, sg,
4029 			cmd->t_tasks_sg_chained_no, i) {
4030 
4031 		pr_debug("SG[%d]: %p page: %p length: %d offset: %d\n",
4032 			i, sg, sg_page(sg), sg->length, sg->offset);
4033 		if (sg_is_chain(sg))
4034 			pr_debug("SG: %p sg_is_chain=1\n", sg);
4035 		if (sg_is_last(sg))
4036 			pr_debug("SG: %p sg_is_last=1\n", sg);
4037 	}
4038 }
4039 EXPORT_SYMBOL(transport_do_task_sg_chain);
4040 
4041 /*
4042  * Break up cmd into chunks transport can handle
4043  */
4044 static int transport_allocate_data_tasks(
4045 	struct se_cmd *cmd,
4046 	unsigned long long lba,
4047 	enum dma_data_direction data_direction,
4048 	struct scatterlist *sgl,
4049 	unsigned int sgl_nents)
4050 {
4051 	unsigned char *cdb = NULL;
4052 	struct se_task *task;
4053 	struct se_device *dev = cmd->se_dev;
4054 	unsigned long flags;
4055 	sector_t sectors;
4056 	int task_count, i, ret;
4057 	sector_t dev_max_sectors = dev->se_sub_dev->se_dev_attrib.max_sectors;
4058 	u32 sector_size = dev->se_sub_dev->se_dev_attrib.block_size;
4059 	struct scatterlist *sg;
4060 	struct scatterlist *cmd_sg;
4061 
4062 	WARN_ON(cmd->data_length % sector_size);
4063 	sectors = DIV_ROUND_UP(cmd->data_length, sector_size);
4064 	task_count = DIV_ROUND_UP(sectors, dev_max_sectors);
4065 
4066 	cmd_sg = sgl;
4067 	for (i = 0; i < task_count; i++) {
4068 		unsigned int task_size;
4069 		int count;
4070 
4071 		task = transport_generic_get_task(cmd, data_direction);
4072 		if (!task)
4073 			return -ENOMEM;
4074 
4075 		task->task_lba = lba;
4076 		task->task_sectors = min(sectors, dev_max_sectors);
4077 		task->task_size = task->task_sectors * sector_size;
4078 
4079 		cdb = dev->transport->get_cdb(task);
4080 		BUG_ON(!cdb);
4081 
4082 		memcpy(cdb, cmd->t_task_cdb,
4083 		       scsi_command_size(cmd->t_task_cdb));
4084 
4085 		/* Update new cdb with updated lba/sectors */
4086 		cmd->transport_split_cdb(task->task_lba, task->task_sectors, cdb);
4087 
4088 		/*
4089 		 * Check if the fabric module driver is requesting that all
4090 		 * struct se_task->task_sg[] be chained together..  If so,
4091 		 * then allocate an extra padding SG entry for linking and
4092 		 * marking the end of the chained SGL.
4093 		 * Possibly over-allocate task sgl size by using cmd sgl size.
4094 		 * It's so much easier and only a waste when task_count > 1.
4095 		 * That is extremely rare.
4096 		 */
4097 		task->task_sg_nents = sgl_nents;
4098 		if (cmd->se_tfo->task_sg_chaining) {
4099 			task->task_sg_nents++;
4100 			task->task_padded_sg = 1;
4101 		}
4102 
4103 		task->task_sg = kmalloc(sizeof(struct scatterlist) *
4104 					task->task_sg_nents, GFP_KERNEL);
4105 		if (!task->task_sg) {
4106 			cmd->se_dev->transport->free_task(task);
4107 			return -ENOMEM;
4108 		}
4109 
4110 		sg_init_table(task->task_sg, task->task_sg_nents);
4111 
4112 		task_size = task->task_size;
4113 
4114 		/* Build new sgl, only up to task_size */
4115 		for_each_sg(task->task_sg, sg, task->task_sg_nents, count) {
4116 			if (cmd_sg->length > task_size)
4117 				break;
4118 
4119 			*sg = *cmd_sg;
4120 			task_size -= cmd_sg->length;
4121 			cmd_sg = sg_next(cmd_sg);
4122 		}
4123 
4124 		lba += task->task_sectors;
4125 		sectors -= task->task_sectors;
4126 
4127 		spin_lock_irqsave(&cmd->t_state_lock, flags);
4128 		list_add_tail(&task->t_list, &cmd->t_task_list);
4129 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4130 	}
4131 	/*
4132 	 * Now perform the memory map of task->task_sg[] into backend
4133 	 * subsystem memory..
4134 	 */
4135 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
4136 		if (atomic_read(&task->task_sent))
4137 			continue;
4138 		if (!dev->transport->map_data_SG)
4139 			continue;
4140 
4141 		ret = dev->transport->map_data_SG(task);
4142 		if (ret < 0)
4143 			return 0;
4144 	}
4145 
4146 	return task_count;
4147 }
4148 
4149 static int
4150 transport_allocate_control_task(struct se_cmd *cmd)
4151 {
4152 	struct se_device *dev = cmd->se_dev;
4153 	unsigned char *cdb;
4154 	struct se_task *task;
4155 	unsigned long flags;
4156 	int ret = 0;
4157 
4158 	task = transport_generic_get_task(cmd, cmd->data_direction);
4159 	if (!task)
4160 		return -ENOMEM;
4161 
4162 	cdb = dev->transport->get_cdb(task);
4163 	BUG_ON(!cdb);
4164 	memcpy(cdb, cmd->t_task_cdb,
4165 	       scsi_command_size(cmd->t_task_cdb));
4166 
4167 	task->task_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
4168 				GFP_KERNEL);
4169 	if (!task->task_sg) {
4170 		cmd->se_dev->transport->free_task(task);
4171 		return -ENOMEM;
4172 	}
4173 
4174 	memcpy(task->task_sg, cmd->t_data_sg,
4175 	       sizeof(struct scatterlist) * cmd->t_data_nents);
4176 	task->task_size = cmd->data_length;
4177 	task->task_sg_nents = cmd->t_data_nents;
4178 
4179 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4180 	list_add_tail(&task->t_list, &cmd->t_task_list);
4181 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4182 
4183 	if (cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) {
4184 		if (dev->transport->map_control_SG)
4185 			ret = dev->transport->map_control_SG(task);
4186 	} else if (cmd->se_cmd_flags & SCF_SCSI_NON_DATA_CDB) {
4187 		if (dev->transport->cdb_none)
4188 			ret = dev->transport->cdb_none(task);
4189 	} else {
4190 		pr_err("target: Unknown control cmd type!\n");
4191 		BUG();
4192 	}
4193 
4194 	/* Success! Return number of tasks allocated */
4195 	if (ret == 0)
4196 		return 1;
4197 	return ret;
4198 }
4199 
4200 static u32 transport_allocate_tasks(
4201 	struct se_cmd *cmd,
4202 	unsigned long long lba,
4203 	enum dma_data_direction data_direction,
4204 	struct scatterlist *sgl,
4205 	unsigned int sgl_nents)
4206 {
4207 	if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)
4208 		return transport_allocate_data_tasks(cmd, lba, data_direction,
4209 						     sgl, sgl_nents);
4210 	else
4211 		return transport_allocate_control_task(cmd);
4212 
4213 }
4214 
4215 
4216 /*	 transport_generic_new_cmd(): Called from transport_processing_thread()
4217  *
4218  *	 Allocate storage transport resources from a set of values predefined
4219  *	 by transport_generic_cmd_sequencer() from the iSCSI Target RX process.
4220  *	 Any non zero return here is treated as an "out of resource' op here.
4221  */
4222 	/*
4223 	 * Generate struct se_task(s) and/or their payloads for this CDB.
4224 	 */
4225 int transport_generic_new_cmd(struct se_cmd *cmd)
4226 {
4227 	int ret = 0;
4228 
4229 	/*
4230 	 * Determine is the TCM fabric module has already allocated physical
4231 	 * memory, and is directly calling transport_generic_map_mem_to_cmd()
4232 	 * beforehand.
4233 	 */
4234 	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
4235 	    cmd->data_length) {
4236 		ret = transport_generic_get_mem(cmd);
4237 		if (ret < 0)
4238 			return ret;
4239 	}
4240 	/*
4241 	 * Call transport_new_cmd_obj() to invoke transport_allocate_tasks() for
4242 	 * control or data CDB types, and perform the map to backend subsystem
4243 	 * code from SGL memory allocated here by transport_generic_get_mem(), or
4244 	 * via pre-existing SGL memory setup explictly by fabric module code with
4245 	 * transport_generic_map_mem_to_cmd().
4246 	 */
4247 	ret = transport_new_cmd_obj(cmd);
4248 	if (ret < 0)
4249 		return ret;
4250 	/*
4251 	 * For WRITEs, let the fabric know its buffer is ready..
4252 	 * This WRITE struct se_cmd (and all of its associated struct se_task's)
4253 	 * will be added to the struct se_device execution queue after its WRITE
4254 	 * data has arrived. (ie: It gets handled by the transport processing
4255 	 * thread a second time)
4256 	 */
4257 	if (cmd->data_direction == DMA_TO_DEVICE) {
4258 		transport_add_tasks_to_state_queue(cmd);
4259 		return transport_generic_write_pending(cmd);
4260 	}
4261 	/*
4262 	 * Everything else but a WRITE, add the struct se_cmd's struct se_task's
4263 	 * to the execution queue.
4264 	 */
4265 	transport_execute_tasks(cmd);
4266 	return 0;
4267 }
4268 EXPORT_SYMBOL(transport_generic_new_cmd);
4269 
4270 /*	transport_generic_process_write():
4271  *
4272  *
4273  */
4274 void transport_generic_process_write(struct se_cmd *cmd)
4275 {
4276 	transport_execute_tasks(cmd);
4277 }
4278 EXPORT_SYMBOL(transport_generic_process_write);
4279 
4280 static int transport_write_pending_qf(struct se_cmd *cmd)
4281 {
4282 	return cmd->se_tfo->write_pending(cmd);
4283 }
4284 
4285 /*	transport_generic_write_pending():
4286  *
4287  *
4288  */
4289 static int transport_generic_write_pending(struct se_cmd *cmd)
4290 {
4291 	unsigned long flags;
4292 	int ret;
4293 
4294 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4295 	cmd->t_state = TRANSPORT_WRITE_PENDING;
4296 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4297 
4298 	if (cmd->transport_qf_callback) {
4299 		ret = cmd->transport_qf_callback(cmd);
4300 		if (ret == -EAGAIN)
4301 			goto queue_full;
4302 		else if (ret < 0)
4303 			return ret;
4304 
4305 		cmd->transport_qf_callback = NULL;
4306 		return 0;
4307 	}
4308 
4309 	/*
4310 	 * Clear the se_cmd for WRITE_PENDING status in order to set
4311 	 * cmd->t_transport_active=0 so that transport_generic_handle_data
4312 	 * can be called from HW target mode interrupt code.  This is safe
4313 	 * to be called with transport_off=1 before the cmd->se_tfo->write_pending
4314 	 * because the se_cmd->se_lun pointer is not being cleared.
4315 	 */
4316 	transport_cmd_check_stop(cmd, 1, 0);
4317 
4318 	/*
4319 	 * Call the fabric write_pending function here to let the
4320 	 * frontend know that WRITE buffers are ready.
4321 	 */
4322 	ret = cmd->se_tfo->write_pending(cmd);
4323 	if (ret == -EAGAIN)
4324 		goto queue_full;
4325 	else if (ret < 0)
4326 		return ret;
4327 
4328 	return PYX_TRANSPORT_WRITE_PENDING;
4329 
4330 queue_full:
4331 	pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
4332 	cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
4333 	transport_handle_queue_full(cmd, cmd->se_dev,
4334 			transport_write_pending_qf);
4335 	return ret;
4336 }
4337 
4338 void transport_release_cmd(struct se_cmd *cmd)
4339 {
4340 	BUG_ON(!cmd->se_tfo);
4341 
4342 	transport_free_se_cmd(cmd);
4343 	cmd->se_tfo->release_cmd(cmd);
4344 }
4345 EXPORT_SYMBOL(transport_release_cmd);
4346 
4347 /*	transport_generic_free_cmd():
4348  *
4349  *	Called from processing frontend to release storage engine resources
4350  */
4351 void transport_generic_free_cmd(
4352 	struct se_cmd *cmd,
4353 	int wait_for_tasks,
4354 	int session_reinstatement)
4355 {
4356 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD))
4357 		transport_release_cmd(cmd);
4358 	else {
4359 		core_dec_lacl_count(cmd->se_sess->se_node_acl, cmd);
4360 
4361 		if (cmd->se_lun) {
4362 #if 0
4363 			pr_debug("cmd: %p ITT: 0x%08x contains"
4364 				" cmd->se_lun\n", cmd,
4365 				cmd->se_tfo->get_task_tag(cmd));
4366 #endif
4367 			transport_lun_remove_cmd(cmd);
4368 		}
4369 
4370 		if (wait_for_tasks && cmd->transport_wait_for_tasks)
4371 			cmd->transport_wait_for_tasks(cmd, 0, 0);
4372 
4373 		transport_free_dev_tasks(cmd);
4374 
4375 		transport_generic_remove(cmd, session_reinstatement);
4376 	}
4377 }
4378 EXPORT_SYMBOL(transport_generic_free_cmd);
4379 
4380 static void transport_nop_wait_for_tasks(
4381 	struct se_cmd *cmd,
4382 	int remove_cmd,
4383 	int session_reinstatement)
4384 {
4385 	return;
4386 }
4387 
4388 /*	transport_lun_wait_for_tasks():
4389  *
4390  *	Called from ConfigFS context to stop the passed struct se_cmd to allow
4391  *	an struct se_lun to be successfully shutdown.
4392  */
4393 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
4394 {
4395 	unsigned long flags;
4396 	int ret;
4397 	/*
4398 	 * If the frontend has already requested this struct se_cmd to
4399 	 * be stopped, we can safely ignore this struct se_cmd.
4400 	 */
4401 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4402 	if (atomic_read(&cmd->t_transport_stop)) {
4403 		atomic_set(&cmd->transport_lun_stop, 0);
4404 		pr_debug("ConfigFS ITT[0x%08x] - t_transport_stop =="
4405 			" TRUE, skipping\n", cmd->se_tfo->get_task_tag(cmd));
4406 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4407 		transport_cmd_check_stop(cmd, 1, 0);
4408 		return -EPERM;
4409 	}
4410 	atomic_set(&cmd->transport_lun_fe_stop, 1);
4411 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4412 
4413 	wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
4414 
4415 	ret = transport_stop_tasks_for_cmd(cmd);
4416 
4417 	pr_debug("ConfigFS: cmd: %p t_tasks: %d stop tasks ret:"
4418 			" %d\n", cmd, cmd->t_task_list_num, ret);
4419 	if (!ret) {
4420 		pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
4421 				cmd->se_tfo->get_task_tag(cmd));
4422 		wait_for_completion(&cmd->transport_lun_stop_comp);
4423 		pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
4424 				cmd->se_tfo->get_task_tag(cmd));
4425 	}
4426 	transport_remove_cmd_from_queue(cmd, &cmd->se_dev->dev_queue_obj);
4427 
4428 	return 0;
4429 }
4430 
4431 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
4432 {
4433 	struct se_cmd *cmd = NULL;
4434 	unsigned long lun_flags, cmd_flags;
4435 	/*
4436 	 * Do exception processing and return CHECK_CONDITION status to the
4437 	 * Initiator Port.
4438 	 */
4439 	spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4440 	while (!list_empty(&lun->lun_cmd_list)) {
4441 		cmd = list_first_entry(&lun->lun_cmd_list,
4442 		       struct se_cmd, se_lun_node);
4443 		list_del(&cmd->se_lun_node);
4444 
4445 		atomic_set(&cmd->transport_lun_active, 0);
4446 		/*
4447 		 * This will notify iscsi_target_transport.c:
4448 		 * transport_cmd_check_stop() that a LUN shutdown is in
4449 		 * progress for the iscsi_cmd_t.
4450 		 */
4451 		spin_lock(&cmd->t_state_lock);
4452 		pr_debug("SE_LUN[%d] - Setting cmd->transport"
4453 			"_lun_stop for  ITT: 0x%08x\n",
4454 			cmd->se_lun->unpacked_lun,
4455 			cmd->se_tfo->get_task_tag(cmd));
4456 		atomic_set(&cmd->transport_lun_stop, 1);
4457 		spin_unlock(&cmd->t_state_lock);
4458 
4459 		spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
4460 
4461 		if (!cmd->se_lun) {
4462 			pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
4463 				cmd->se_tfo->get_task_tag(cmd),
4464 				cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
4465 			BUG();
4466 		}
4467 		/*
4468 		 * If the Storage engine still owns the iscsi_cmd_t, determine
4469 		 * and/or stop its context.
4470 		 */
4471 		pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
4472 			"_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
4473 			cmd->se_tfo->get_task_tag(cmd));
4474 
4475 		if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
4476 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4477 			continue;
4478 		}
4479 
4480 		pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
4481 			"_wait_for_tasks(): SUCCESS\n",
4482 			cmd->se_lun->unpacked_lun,
4483 			cmd->se_tfo->get_task_tag(cmd));
4484 
4485 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
4486 		if (!atomic_read(&cmd->transport_dev_active)) {
4487 			spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4488 			goto check_cond;
4489 		}
4490 		atomic_set(&cmd->transport_dev_active, 0);
4491 		transport_all_task_dev_remove_state(cmd);
4492 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4493 
4494 		transport_free_dev_tasks(cmd);
4495 		/*
4496 		 * The Storage engine stopped this struct se_cmd before it was
4497 		 * send to the fabric frontend for delivery back to the
4498 		 * Initiator Node.  Return this SCSI CDB back with an
4499 		 * CHECK_CONDITION status.
4500 		 */
4501 check_cond:
4502 		transport_send_check_condition_and_sense(cmd,
4503 				TCM_NON_EXISTENT_LUN, 0);
4504 		/*
4505 		 *  If the fabric frontend is waiting for this iscsi_cmd_t to
4506 		 * be released, notify the waiting thread now that LU has
4507 		 * finished accessing it.
4508 		 */
4509 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
4510 		if (atomic_read(&cmd->transport_lun_fe_stop)) {
4511 			pr_debug("SE_LUN[%d] - Detected FE stop for"
4512 				" struct se_cmd: %p ITT: 0x%08x\n",
4513 				lun->unpacked_lun,
4514 				cmd, cmd->se_tfo->get_task_tag(cmd));
4515 
4516 			spin_unlock_irqrestore(&cmd->t_state_lock,
4517 					cmd_flags);
4518 			transport_cmd_check_stop(cmd, 1, 0);
4519 			complete(&cmd->transport_lun_fe_stop_comp);
4520 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4521 			continue;
4522 		}
4523 		pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
4524 			lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
4525 
4526 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4527 		spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4528 	}
4529 	spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
4530 }
4531 
4532 static int transport_clear_lun_thread(void *p)
4533 {
4534 	struct se_lun *lun = (struct se_lun *)p;
4535 
4536 	__transport_clear_lun_from_sessions(lun);
4537 	complete(&lun->lun_shutdown_comp);
4538 
4539 	return 0;
4540 }
4541 
4542 int transport_clear_lun_from_sessions(struct se_lun *lun)
4543 {
4544 	struct task_struct *kt;
4545 
4546 	kt = kthread_run(transport_clear_lun_thread, lun,
4547 			"tcm_cl_%u", lun->unpacked_lun);
4548 	if (IS_ERR(kt)) {
4549 		pr_err("Unable to start clear_lun thread\n");
4550 		return PTR_ERR(kt);
4551 	}
4552 	wait_for_completion(&lun->lun_shutdown_comp);
4553 
4554 	return 0;
4555 }
4556 
4557 /*	transport_generic_wait_for_tasks():
4558  *
4559  *	Called from frontend or passthrough context to wait for storage engine
4560  *	to pause and/or release frontend generated struct se_cmd.
4561  */
4562 static void transport_generic_wait_for_tasks(
4563 	struct se_cmd *cmd,
4564 	int remove_cmd,
4565 	int session_reinstatement)
4566 {
4567 	unsigned long flags;
4568 
4569 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) && !(cmd->se_tmr_req))
4570 		return;
4571 
4572 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4573 	/*
4574 	 * If we are already stopped due to an external event (ie: LUN shutdown)
4575 	 * sleep until the connection can have the passed struct se_cmd back.
4576 	 * The cmd->transport_lun_stopped_sem will be upped by
4577 	 * transport_clear_lun_from_sessions() once the ConfigFS context caller
4578 	 * has completed its operation on the struct se_cmd.
4579 	 */
4580 	if (atomic_read(&cmd->transport_lun_stop)) {
4581 
4582 		pr_debug("wait_for_tasks: Stopping"
4583 			" wait_for_completion(&cmd->t_tasktransport_lun_fe"
4584 			"_stop_comp); for ITT: 0x%08x\n",
4585 			cmd->se_tfo->get_task_tag(cmd));
4586 		/*
4587 		 * There is a special case for WRITES where a FE exception +
4588 		 * LUN shutdown means ConfigFS context is still sleeping on
4589 		 * transport_lun_stop_comp in transport_lun_wait_for_tasks().
4590 		 * We go ahead and up transport_lun_stop_comp just to be sure
4591 		 * here.
4592 		 */
4593 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4594 		complete(&cmd->transport_lun_stop_comp);
4595 		wait_for_completion(&cmd->transport_lun_fe_stop_comp);
4596 		spin_lock_irqsave(&cmd->t_state_lock, flags);
4597 
4598 		transport_all_task_dev_remove_state(cmd);
4599 		/*
4600 		 * At this point, the frontend who was the originator of this
4601 		 * struct se_cmd, now owns the structure and can be released through
4602 		 * normal means below.
4603 		 */
4604 		pr_debug("wait_for_tasks: Stopped"
4605 			" wait_for_completion(&cmd->t_tasktransport_lun_fe_"
4606 			"stop_comp); for ITT: 0x%08x\n",
4607 			cmd->se_tfo->get_task_tag(cmd));
4608 
4609 		atomic_set(&cmd->transport_lun_stop, 0);
4610 	}
4611 	if (!atomic_read(&cmd->t_transport_active) ||
4612 	     atomic_read(&cmd->t_transport_aborted))
4613 		goto remove;
4614 
4615 	atomic_set(&cmd->t_transport_stop, 1);
4616 
4617 	pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
4618 		" i_state: %d, t_state/def_t_state: %d/%d, t_transport_stop"
4619 		" = TRUE\n", cmd, cmd->se_tfo->get_task_tag(cmd),
4620 		cmd->se_tfo->get_cmd_state(cmd), cmd->t_state,
4621 		cmd->deferred_t_state);
4622 
4623 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4624 
4625 	wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
4626 
4627 	wait_for_completion(&cmd->t_transport_stop_comp);
4628 
4629 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4630 	atomic_set(&cmd->t_transport_active, 0);
4631 	atomic_set(&cmd->t_transport_stop, 0);
4632 
4633 	pr_debug("wait_for_tasks: Stopped wait_for_compltion("
4634 		"&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
4635 		cmd->se_tfo->get_task_tag(cmd));
4636 remove:
4637 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4638 	if (!remove_cmd)
4639 		return;
4640 
4641 	transport_generic_free_cmd(cmd, 0, session_reinstatement);
4642 }
4643 
4644 static int transport_get_sense_codes(
4645 	struct se_cmd *cmd,
4646 	u8 *asc,
4647 	u8 *ascq)
4648 {
4649 	*asc = cmd->scsi_asc;
4650 	*ascq = cmd->scsi_ascq;
4651 
4652 	return 0;
4653 }
4654 
4655 static int transport_set_sense_codes(
4656 	struct se_cmd *cmd,
4657 	u8 asc,
4658 	u8 ascq)
4659 {
4660 	cmd->scsi_asc = asc;
4661 	cmd->scsi_ascq = ascq;
4662 
4663 	return 0;
4664 }
4665 
4666 int transport_send_check_condition_and_sense(
4667 	struct se_cmd *cmd,
4668 	u8 reason,
4669 	int from_transport)
4670 {
4671 	unsigned char *buffer = cmd->sense_buffer;
4672 	unsigned long flags;
4673 	int offset;
4674 	u8 asc = 0, ascq = 0;
4675 
4676 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4677 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
4678 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4679 		return 0;
4680 	}
4681 	cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
4682 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4683 
4684 	if (!reason && from_transport)
4685 		goto after_reason;
4686 
4687 	if (!from_transport)
4688 		cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
4689 	/*
4690 	 * Data Segment and SenseLength of the fabric response PDU.
4691 	 *
4692 	 * TRANSPORT_SENSE_BUFFER is now set to SCSI_SENSE_BUFFERSIZE
4693 	 * from include/scsi/scsi_cmnd.h
4694 	 */
4695 	offset = cmd->se_tfo->set_fabric_sense_len(cmd,
4696 				TRANSPORT_SENSE_BUFFER);
4697 	/*
4698 	 * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
4699 	 * SENSE KEY values from include/scsi/scsi.h
4700 	 */
4701 	switch (reason) {
4702 	case TCM_NON_EXISTENT_LUN:
4703 	case TCM_UNSUPPORTED_SCSI_OPCODE:
4704 	case TCM_SECTOR_COUNT_TOO_MANY:
4705 		/* CURRENT ERROR */
4706 		buffer[offset] = 0x70;
4707 		/* ILLEGAL REQUEST */
4708 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4709 		/* INVALID COMMAND OPERATION CODE */
4710 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x20;
4711 		break;
4712 	case TCM_UNKNOWN_MODE_PAGE:
4713 		/* CURRENT ERROR */
4714 		buffer[offset] = 0x70;
4715 		/* ILLEGAL REQUEST */
4716 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4717 		/* INVALID FIELD IN CDB */
4718 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
4719 		break;
4720 	case TCM_CHECK_CONDITION_ABORT_CMD:
4721 		/* CURRENT ERROR */
4722 		buffer[offset] = 0x70;
4723 		/* ABORTED COMMAND */
4724 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4725 		/* BUS DEVICE RESET FUNCTION OCCURRED */
4726 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x29;
4727 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x03;
4728 		break;
4729 	case TCM_INCORRECT_AMOUNT_OF_DATA:
4730 		/* CURRENT ERROR */
4731 		buffer[offset] = 0x70;
4732 		/* ABORTED COMMAND */
4733 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4734 		/* WRITE ERROR */
4735 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x0c;
4736 		/* NOT ENOUGH UNSOLICITED DATA */
4737 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0d;
4738 		break;
4739 	case TCM_INVALID_CDB_FIELD:
4740 		/* CURRENT ERROR */
4741 		buffer[offset] = 0x70;
4742 		/* ABORTED COMMAND */
4743 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4744 		/* INVALID FIELD IN CDB */
4745 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
4746 		break;
4747 	case TCM_INVALID_PARAMETER_LIST:
4748 		/* CURRENT ERROR */
4749 		buffer[offset] = 0x70;
4750 		/* ABORTED COMMAND */
4751 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4752 		/* INVALID FIELD IN PARAMETER LIST */
4753 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x26;
4754 		break;
4755 	case TCM_UNEXPECTED_UNSOLICITED_DATA:
4756 		/* CURRENT ERROR */
4757 		buffer[offset] = 0x70;
4758 		/* ABORTED COMMAND */
4759 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4760 		/* WRITE ERROR */
4761 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x0c;
4762 		/* UNEXPECTED_UNSOLICITED_DATA */
4763 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0c;
4764 		break;
4765 	case TCM_SERVICE_CRC_ERROR:
4766 		/* CURRENT ERROR */
4767 		buffer[offset] = 0x70;
4768 		/* ABORTED COMMAND */
4769 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4770 		/* PROTOCOL SERVICE CRC ERROR */
4771 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x47;
4772 		/* N/A */
4773 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x05;
4774 		break;
4775 	case TCM_SNACK_REJECTED:
4776 		/* CURRENT ERROR */
4777 		buffer[offset] = 0x70;
4778 		/* ABORTED COMMAND */
4779 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4780 		/* READ ERROR */
4781 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x11;
4782 		/* FAILED RETRANSMISSION REQUEST */
4783 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x13;
4784 		break;
4785 	case TCM_WRITE_PROTECTED:
4786 		/* CURRENT ERROR */
4787 		buffer[offset] = 0x70;
4788 		/* DATA PROTECT */
4789 		buffer[offset+SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
4790 		/* WRITE PROTECTED */
4791 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x27;
4792 		break;
4793 	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
4794 		/* CURRENT ERROR */
4795 		buffer[offset] = 0x70;
4796 		/* UNIT ATTENTION */
4797 		buffer[offset+SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
4798 		core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
4799 		buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
4800 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
4801 		break;
4802 	case TCM_CHECK_CONDITION_NOT_READY:
4803 		/* CURRENT ERROR */
4804 		buffer[offset] = 0x70;
4805 		/* Not Ready */
4806 		buffer[offset+SPC_SENSE_KEY_OFFSET] = NOT_READY;
4807 		transport_get_sense_codes(cmd, &asc, &ascq);
4808 		buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
4809 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
4810 		break;
4811 	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
4812 	default:
4813 		/* CURRENT ERROR */
4814 		buffer[offset] = 0x70;
4815 		/* ILLEGAL REQUEST */
4816 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4817 		/* LOGICAL UNIT COMMUNICATION FAILURE */
4818 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x80;
4819 		break;
4820 	}
4821 	/*
4822 	 * This code uses linux/include/scsi/scsi.h SAM status codes!
4823 	 */
4824 	cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
4825 	/*
4826 	 * Automatically padded, this value is encoded in the fabric's
4827 	 * data_length response PDU containing the SCSI defined sense data.
4828 	 */
4829 	cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER + offset;
4830 
4831 after_reason:
4832 	return cmd->se_tfo->queue_status(cmd);
4833 }
4834 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
4835 
4836 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
4837 {
4838 	int ret = 0;
4839 
4840 	if (atomic_read(&cmd->t_transport_aborted) != 0) {
4841 		if (!send_status ||
4842 		     (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
4843 			return 1;
4844 #if 0
4845 		pr_debug("Sending delayed SAM_STAT_TASK_ABORTED"
4846 			" status for CDB: 0x%02x ITT: 0x%08x\n",
4847 			cmd->t_task_cdb[0],
4848 			cmd->se_tfo->get_task_tag(cmd));
4849 #endif
4850 		cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
4851 		cmd->se_tfo->queue_status(cmd);
4852 		ret = 1;
4853 	}
4854 	return ret;
4855 }
4856 EXPORT_SYMBOL(transport_check_aborted_status);
4857 
4858 void transport_send_task_abort(struct se_cmd *cmd)
4859 {
4860 	/*
4861 	 * If there are still expected incoming fabric WRITEs, we wait
4862 	 * until until they have completed before sending a TASK_ABORTED
4863 	 * response.  This response with TASK_ABORTED status will be
4864 	 * queued back to fabric module by transport_check_aborted_status().
4865 	 */
4866 	if (cmd->data_direction == DMA_TO_DEVICE) {
4867 		if (cmd->se_tfo->write_pending_status(cmd) != 0) {
4868 			atomic_inc(&cmd->t_transport_aborted);
4869 			smp_mb__after_atomic_inc();
4870 			cmd->scsi_status = SAM_STAT_TASK_ABORTED;
4871 			transport_new_cmd_failure(cmd);
4872 			return;
4873 		}
4874 	}
4875 	cmd->scsi_status = SAM_STAT_TASK_ABORTED;
4876 #if 0
4877 	pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
4878 		" ITT: 0x%08x\n", cmd->t_task_cdb[0],
4879 		cmd->se_tfo->get_task_tag(cmd));
4880 #endif
4881 	cmd->se_tfo->queue_status(cmd);
4882 }
4883 
4884 /*	transport_generic_do_tmr():
4885  *
4886  *
4887  */
4888 int transport_generic_do_tmr(struct se_cmd *cmd)
4889 {
4890 	struct se_device *dev = cmd->se_dev;
4891 	struct se_tmr_req *tmr = cmd->se_tmr_req;
4892 	int ret;
4893 
4894 	switch (tmr->function) {
4895 	case TMR_ABORT_TASK:
4896 		tmr->response = TMR_FUNCTION_REJECTED;
4897 		break;
4898 	case TMR_ABORT_TASK_SET:
4899 	case TMR_CLEAR_ACA:
4900 	case TMR_CLEAR_TASK_SET:
4901 		tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
4902 		break;
4903 	case TMR_LUN_RESET:
4904 		ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
4905 		tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
4906 					 TMR_FUNCTION_REJECTED;
4907 		break;
4908 	case TMR_TARGET_WARM_RESET:
4909 		tmr->response = TMR_FUNCTION_REJECTED;
4910 		break;
4911 	case TMR_TARGET_COLD_RESET:
4912 		tmr->response = TMR_FUNCTION_REJECTED;
4913 		break;
4914 	default:
4915 		pr_err("Uknown TMR function: 0x%02x.\n",
4916 				tmr->function);
4917 		tmr->response = TMR_FUNCTION_REJECTED;
4918 		break;
4919 	}
4920 
4921 	cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
4922 	cmd->se_tfo->queue_tm_rsp(cmd);
4923 
4924 	transport_cmd_check_stop(cmd, 2, 0);
4925 	return 0;
4926 }
4927 
4928 /*
4929  *	Called with spin_lock_irq(&dev->execute_task_lock); held
4930  *
4931  */
4932 static struct se_task *
4933 transport_get_task_from_state_list(struct se_device *dev)
4934 {
4935 	struct se_task *task;
4936 
4937 	if (list_empty(&dev->state_task_list))
4938 		return NULL;
4939 
4940 	list_for_each_entry(task, &dev->state_task_list, t_state_list)
4941 		break;
4942 
4943 	list_del(&task->t_state_list);
4944 	atomic_set(&task->task_state_active, 0);
4945 
4946 	return task;
4947 }
4948 
4949 static void transport_processing_shutdown(struct se_device *dev)
4950 {
4951 	struct se_cmd *cmd;
4952 	struct se_task *task;
4953 	unsigned long flags;
4954 	/*
4955 	 * Empty the struct se_device's struct se_task state list.
4956 	 */
4957 	spin_lock_irqsave(&dev->execute_task_lock, flags);
4958 	while ((task = transport_get_task_from_state_list(dev))) {
4959 		if (!task->task_se_cmd) {
4960 			pr_err("task->task_se_cmd is NULL!\n");
4961 			continue;
4962 		}
4963 		cmd = task->task_se_cmd;
4964 
4965 		spin_unlock_irqrestore(&dev->execute_task_lock, flags);
4966 
4967 		spin_lock_irqsave(&cmd->t_state_lock, flags);
4968 
4969 		pr_debug("PT: cmd: %p task: %p ITT: 0x%08x,"
4970 			" i_state: %d, t_state/def_t_state:"
4971 			" %d/%d cdb: 0x%02x\n", cmd, task,
4972 			cmd->se_tfo->get_task_tag(cmd),
4973 			cmd->se_tfo->get_cmd_state(cmd),
4974 			cmd->t_state, cmd->deferred_t_state,
4975 			cmd->t_task_cdb[0]);
4976 		pr_debug("PT: ITT[0x%08x] - t_tasks: %d t_task_cdbs_left:"
4977 			" %d t_task_cdbs_sent: %d -- t_transport_active: %d"
4978 			" t_transport_stop: %d t_transport_sent: %d\n",
4979 			cmd->se_tfo->get_task_tag(cmd),
4980 			cmd->t_task_list_num,
4981 			atomic_read(&cmd->t_task_cdbs_left),
4982 			atomic_read(&cmd->t_task_cdbs_sent),
4983 			atomic_read(&cmd->t_transport_active),
4984 			atomic_read(&cmd->t_transport_stop),
4985 			atomic_read(&cmd->t_transport_sent));
4986 
4987 		if (atomic_read(&task->task_active)) {
4988 			atomic_set(&task->task_stop, 1);
4989 			spin_unlock_irqrestore(
4990 				&cmd->t_state_lock, flags);
4991 
4992 			pr_debug("Waiting for task: %p to shutdown for dev:"
4993 				" %p\n", task, dev);
4994 			wait_for_completion(&task->task_stop_comp);
4995 			pr_debug("Completed task: %p shutdown for dev: %p\n",
4996 				task, dev);
4997 
4998 			spin_lock_irqsave(&cmd->t_state_lock, flags);
4999 			atomic_dec(&cmd->t_task_cdbs_left);
5000 
5001 			atomic_set(&task->task_active, 0);
5002 			atomic_set(&task->task_stop, 0);
5003 		} else {
5004 			if (atomic_read(&task->task_execute_queue) != 0)
5005 				transport_remove_task_from_execute_queue(task, dev);
5006 		}
5007 		__transport_stop_task_timer(task, &flags);
5008 
5009 		if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) {
5010 			spin_unlock_irqrestore(
5011 					&cmd->t_state_lock, flags);
5012 
5013 			pr_debug("Skipping task: %p, dev: %p for"
5014 				" t_task_cdbs_ex_left: %d\n", task, dev,
5015 				atomic_read(&cmd->t_task_cdbs_ex_left));
5016 
5017 			spin_lock_irqsave(&dev->execute_task_lock, flags);
5018 			continue;
5019 		}
5020 
5021 		if (atomic_read(&cmd->t_transport_active)) {
5022 			pr_debug("got t_transport_active = 1 for task: %p, dev:"
5023 					" %p\n", task, dev);
5024 
5025 			if (atomic_read(&cmd->t_fe_count)) {
5026 				spin_unlock_irqrestore(
5027 					&cmd->t_state_lock, flags);
5028 				transport_send_check_condition_and_sense(
5029 					cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE,
5030 					0);
5031 				transport_remove_cmd_from_queue(cmd,
5032 					&cmd->se_dev->dev_queue_obj);
5033 
5034 				transport_lun_remove_cmd(cmd);
5035 				transport_cmd_check_stop(cmd, 1, 0);
5036 			} else {
5037 				spin_unlock_irqrestore(
5038 					&cmd->t_state_lock, flags);
5039 
5040 				transport_remove_cmd_from_queue(cmd,
5041 					&cmd->se_dev->dev_queue_obj);
5042 
5043 				transport_lun_remove_cmd(cmd);
5044 
5045 				if (transport_cmd_check_stop(cmd, 1, 0))
5046 					transport_generic_remove(cmd, 0);
5047 			}
5048 
5049 			spin_lock_irqsave(&dev->execute_task_lock, flags);
5050 			continue;
5051 		}
5052 		pr_debug("Got t_transport_active = 0 for task: %p, dev: %p\n",
5053 				task, dev);
5054 
5055 		if (atomic_read(&cmd->t_fe_count)) {
5056 			spin_unlock_irqrestore(
5057 				&cmd->t_state_lock, flags);
5058 			transport_send_check_condition_and_sense(cmd,
5059 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
5060 			transport_remove_cmd_from_queue(cmd,
5061 				&cmd->se_dev->dev_queue_obj);
5062 
5063 			transport_lun_remove_cmd(cmd);
5064 			transport_cmd_check_stop(cmd, 1, 0);
5065 		} else {
5066 			spin_unlock_irqrestore(
5067 				&cmd->t_state_lock, flags);
5068 
5069 			transport_remove_cmd_from_queue(cmd,
5070 				&cmd->se_dev->dev_queue_obj);
5071 			transport_lun_remove_cmd(cmd);
5072 
5073 			if (transport_cmd_check_stop(cmd, 1, 0))
5074 				transport_generic_remove(cmd, 0);
5075 		}
5076 
5077 		spin_lock_irqsave(&dev->execute_task_lock, flags);
5078 	}
5079 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
5080 	/*
5081 	 * Empty the struct se_device's struct se_cmd list.
5082 	 */
5083 	while ((cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj))) {
5084 
5085 		pr_debug("From Device Queue: cmd: %p t_state: %d\n",
5086 				cmd, cmd->t_state);
5087 
5088 		if (atomic_read(&cmd->t_fe_count)) {
5089 			transport_send_check_condition_and_sense(cmd,
5090 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
5091 
5092 			transport_lun_remove_cmd(cmd);
5093 			transport_cmd_check_stop(cmd, 1, 0);
5094 		} else {
5095 			transport_lun_remove_cmd(cmd);
5096 			if (transport_cmd_check_stop(cmd, 1, 0))
5097 				transport_generic_remove(cmd, 0);
5098 		}
5099 	}
5100 }
5101 
5102 /*	transport_processing_thread():
5103  *
5104  *
5105  */
5106 static int transport_processing_thread(void *param)
5107 {
5108 	int ret;
5109 	struct se_cmd *cmd;
5110 	struct se_device *dev = (struct se_device *) param;
5111 
5112 	set_user_nice(current, -20);
5113 
5114 	while (!kthread_should_stop()) {
5115 		ret = wait_event_interruptible(dev->dev_queue_obj.thread_wq,
5116 				atomic_read(&dev->dev_queue_obj.queue_cnt) ||
5117 				kthread_should_stop());
5118 		if (ret < 0)
5119 			goto out;
5120 
5121 		spin_lock_irq(&dev->dev_status_lock);
5122 		if (dev->dev_status & TRANSPORT_DEVICE_SHUTDOWN) {
5123 			spin_unlock_irq(&dev->dev_status_lock);
5124 			transport_processing_shutdown(dev);
5125 			continue;
5126 		}
5127 		spin_unlock_irq(&dev->dev_status_lock);
5128 
5129 get_cmd:
5130 		__transport_execute_tasks(dev);
5131 
5132 		cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj);
5133 		if (!cmd)
5134 			continue;
5135 
5136 		switch (cmd->t_state) {
5137 		case TRANSPORT_NEW_CMD_MAP:
5138 			if (!cmd->se_tfo->new_cmd_map) {
5139 				pr_err("cmd->se_tfo->new_cmd_map is"
5140 					" NULL for TRANSPORT_NEW_CMD_MAP\n");
5141 				BUG();
5142 			}
5143 			ret = cmd->se_tfo->new_cmd_map(cmd);
5144 			if (ret < 0) {
5145 				cmd->transport_error_status = ret;
5146 				transport_generic_request_failure(cmd, NULL,
5147 						0, (cmd->data_direction !=
5148 						    DMA_TO_DEVICE));
5149 				break;
5150 			}
5151 			/* Fall through */
5152 		case TRANSPORT_NEW_CMD:
5153 			ret = transport_generic_new_cmd(cmd);
5154 			if (ret == -EAGAIN)
5155 				break;
5156 			else if (ret < 0) {
5157 				cmd->transport_error_status = ret;
5158 				transport_generic_request_failure(cmd, NULL,
5159 					0, (cmd->data_direction !=
5160 					 DMA_TO_DEVICE));
5161 			}
5162 			break;
5163 		case TRANSPORT_PROCESS_WRITE:
5164 			transport_generic_process_write(cmd);
5165 			break;
5166 		case TRANSPORT_COMPLETE_OK:
5167 			transport_stop_all_task_timers(cmd);
5168 			transport_generic_complete_ok(cmd);
5169 			break;
5170 		case TRANSPORT_REMOVE:
5171 			transport_generic_remove(cmd, 0);
5172 			break;
5173 		case TRANSPORT_FREE_CMD_INTR:
5174 			transport_generic_free_cmd(cmd, 0, 0);
5175 			break;
5176 		case TRANSPORT_PROCESS_TMR:
5177 			transport_generic_do_tmr(cmd);
5178 			break;
5179 		case TRANSPORT_COMPLETE_FAILURE:
5180 			transport_generic_request_failure(cmd, NULL, 1, 1);
5181 			break;
5182 		case TRANSPORT_COMPLETE_TIMEOUT:
5183 			transport_stop_all_task_timers(cmd);
5184 			transport_generic_request_timeout(cmd);
5185 			break;
5186 		case TRANSPORT_COMPLETE_QF_WP:
5187 			transport_generic_write_pending(cmd);
5188 			break;
5189 		default:
5190 			pr_err("Unknown t_state: %d deferred_t_state:"
5191 				" %d for ITT: 0x%08x i_state: %d on SE LUN:"
5192 				" %u\n", cmd->t_state, cmd->deferred_t_state,
5193 				cmd->se_tfo->get_task_tag(cmd),
5194 				cmd->se_tfo->get_cmd_state(cmd),
5195 				cmd->se_lun->unpacked_lun);
5196 			BUG();
5197 		}
5198 
5199 		goto get_cmd;
5200 	}
5201 
5202 out:
5203 	transport_release_all_cmds(dev);
5204 	dev->process_thread = NULL;
5205 	return 0;
5206 }
5207