xref: /linux/drivers/target/target_core_transport.c (revision 1ccd4b7bfdcfcc8cc7ffc4a9c11d3ac5b6da8ca0)
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 static void transport_generic_request_failure(struct se_cmd *,
1751 			struct se_device *, int, int);
1752 /*
1753  * Used by fabric module frontends to queue tasks directly.
1754  * Many only be used from process context only
1755  */
1756 int transport_handle_cdb_direct(
1757 	struct se_cmd *cmd)
1758 {
1759 	int ret;
1760 
1761 	if (!cmd->se_lun) {
1762 		dump_stack();
1763 		pr_err("cmd->se_lun is NULL\n");
1764 		return -EINVAL;
1765 	}
1766 	if (in_interrupt()) {
1767 		dump_stack();
1768 		pr_err("transport_generic_handle_cdb cannot be called"
1769 				" from interrupt context\n");
1770 		return -EINVAL;
1771 	}
1772 	/*
1773 	 * Set TRANSPORT_NEW_CMD state and cmd->t_transport_active=1 following
1774 	 * transport_generic_handle_cdb*() -> transport_add_cmd_to_queue()
1775 	 * in existing usage to ensure that outstanding descriptors are handled
1776 	 * correctly during shutdown via transport_generic_wait_for_tasks()
1777 	 *
1778 	 * Also, we don't take cmd->t_state_lock here as we only expect
1779 	 * this to be called for initial descriptor submission.
1780 	 */
1781 	cmd->t_state = TRANSPORT_NEW_CMD;
1782 	atomic_set(&cmd->t_transport_active, 1);
1783 	/*
1784 	 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1785 	 * so follow TRANSPORT_NEW_CMD processing thread context usage
1786 	 * and call transport_generic_request_failure() if necessary..
1787 	 */
1788 	ret = transport_generic_new_cmd(cmd);
1789 	if (ret == -EAGAIN)
1790 		return 0;
1791 	else if (ret < 0) {
1792 		cmd->transport_error_status = ret;
1793 		transport_generic_request_failure(cmd, NULL, 0,
1794 				(cmd->data_direction != DMA_TO_DEVICE));
1795 	}
1796 	return 0;
1797 }
1798 EXPORT_SYMBOL(transport_handle_cdb_direct);
1799 
1800 /*
1801  * Used by fabric module frontends defining a TFO->new_cmd_map() caller
1802  * to  queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD_MAP in order to
1803  * complete setup in TCM process context w/ TFO->new_cmd_map().
1804  */
1805 int transport_generic_handle_cdb_map(
1806 	struct se_cmd *cmd)
1807 {
1808 	if (!cmd->se_lun) {
1809 		dump_stack();
1810 		pr_err("cmd->se_lun is NULL\n");
1811 		return -EINVAL;
1812 	}
1813 
1814 	transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD_MAP);
1815 	return 0;
1816 }
1817 EXPORT_SYMBOL(transport_generic_handle_cdb_map);
1818 
1819 /*	transport_generic_handle_data():
1820  *
1821  *
1822  */
1823 int transport_generic_handle_data(
1824 	struct se_cmd *cmd)
1825 {
1826 	/*
1827 	 * For the software fabric case, then we assume the nexus is being
1828 	 * failed/shutdown when signals are pending from the kthread context
1829 	 * caller, so we return a failure.  For the HW target mode case running
1830 	 * in interrupt code, the signal_pending() check is skipped.
1831 	 */
1832 	if (!in_interrupt() && signal_pending(current))
1833 		return -EPERM;
1834 	/*
1835 	 * If the received CDB has aleady been ABORTED by the generic
1836 	 * target engine, we now call transport_check_aborted_status()
1837 	 * to queue any delated TASK_ABORTED status for the received CDB to the
1838 	 * fabric module as we are expecting no further incoming DATA OUT
1839 	 * sequences at this point.
1840 	 */
1841 	if (transport_check_aborted_status(cmd, 1) != 0)
1842 		return 0;
1843 
1844 	transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_WRITE);
1845 	return 0;
1846 }
1847 EXPORT_SYMBOL(transport_generic_handle_data);
1848 
1849 /*	transport_generic_handle_tmr():
1850  *
1851  *
1852  */
1853 int transport_generic_handle_tmr(
1854 	struct se_cmd *cmd)
1855 {
1856 	/*
1857 	 * This is needed for early exceptions.
1858 	 */
1859 	cmd->transport_wait_for_tasks = &transport_generic_wait_for_tasks;
1860 
1861 	transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_TMR);
1862 	return 0;
1863 }
1864 EXPORT_SYMBOL(transport_generic_handle_tmr);
1865 
1866 void transport_generic_free_cmd_intr(
1867 	struct se_cmd *cmd)
1868 {
1869 	transport_add_cmd_to_queue(cmd, TRANSPORT_FREE_CMD_INTR);
1870 }
1871 EXPORT_SYMBOL(transport_generic_free_cmd_intr);
1872 
1873 static int transport_stop_tasks_for_cmd(struct se_cmd *cmd)
1874 {
1875 	struct se_task *task, *task_tmp;
1876 	unsigned long flags;
1877 	int ret = 0;
1878 
1879 	pr_debug("ITT[0x%08x] - Stopping tasks\n",
1880 		cmd->se_tfo->get_task_tag(cmd));
1881 
1882 	/*
1883 	 * No tasks remain in the execution queue
1884 	 */
1885 	spin_lock_irqsave(&cmd->t_state_lock, flags);
1886 	list_for_each_entry_safe(task, task_tmp,
1887 				&cmd->t_task_list, t_list) {
1888 		pr_debug("task_no[%d] - Processing task %p\n",
1889 				task->task_no, task);
1890 		/*
1891 		 * If the struct se_task has not been sent and is not active,
1892 		 * remove the struct se_task from the execution queue.
1893 		 */
1894 		if (!atomic_read(&task->task_sent) &&
1895 		    !atomic_read(&task->task_active)) {
1896 			spin_unlock_irqrestore(&cmd->t_state_lock,
1897 					flags);
1898 			transport_remove_task_from_execute_queue(task,
1899 					task->se_dev);
1900 
1901 			pr_debug("task_no[%d] - Removed from execute queue\n",
1902 				task->task_no);
1903 			spin_lock_irqsave(&cmd->t_state_lock, flags);
1904 			continue;
1905 		}
1906 
1907 		/*
1908 		 * If the struct se_task is active, sleep until it is returned
1909 		 * from the plugin.
1910 		 */
1911 		if (atomic_read(&task->task_active)) {
1912 			atomic_set(&task->task_stop, 1);
1913 			spin_unlock_irqrestore(&cmd->t_state_lock,
1914 					flags);
1915 
1916 			pr_debug("task_no[%d] - Waiting to complete\n",
1917 				task->task_no);
1918 			wait_for_completion(&task->task_stop_comp);
1919 			pr_debug("task_no[%d] - Stopped successfully\n",
1920 				task->task_no);
1921 
1922 			spin_lock_irqsave(&cmd->t_state_lock, flags);
1923 			atomic_dec(&cmd->t_task_cdbs_left);
1924 
1925 			atomic_set(&task->task_active, 0);
1926 			atomic_set(&task->task_stop, 0);
1927 		} else {
1928 			pr_debug("task_no[%d] - Did nothing\n", task->task_no);
1929 			ret++;
1930 		}
1931 
1932 		__transport_stop_task_timer(task, &flags);
1933 	}
1934 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1935 
1936 	return ret;
1937 }
1938 
1939 /*
1940  * Handle SAM-esque emulation for generic transport request failures.
1941  */
1942 static void transport_generic_request_failure(
1943 	struct se_cmd *cmd,
1944 	struct se_device *dev,
1945 	int complete,
1946 	int sc)
1947 {
1948 	int ret = 0;
1949 
1950 	pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1951 		" CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1952 		cmd->t_task_cdb[0]);
1953 	pr_debug("-----[ i_state: %d t_state/def_t_state:"
1954 		" %d/%d transport_error_status: %d\n",
1955 		cmd->se_tfo->get_cmd_state(cmd),
1956 		cmd->t_state, cmd->deferred_t_state,
1957 		cmd->transport_error_status);
1958 	pr_debug("-----[ t_tasks: %d t_task_cdbs_left: %d"
1959 		" t_task_cdbs_sent: %d t_task_cdbs_ex_left: %d --"
1960 		" t_transport_active: %d t_transport_stop: %d"
1961 		" t_transport_sent: %d\n", cmd->t_task_list_num,
1962 		atomic_read(&cmd->t_task_cdbs_left),
1963 		atomic_read(&cmd->t_task_cdbs_sent),
1964 		atomic_read(&cmd->t_task_cdbs_ex_left),
1965 		atomic_read(&cmd->t_transport_active),
1966 		atomic_read(&cmd->t_transport_stop),
1967 		atomic_read(&cmd->t_transport_sent));
1968 
1969 	transport_stop_all_task_timers(cmd);
1970 
1971 	if (dev)
1972 		atomic_inc(&dev->depth_left);
1973 	/*
1974 	 * For SAM Task Attribute emulation for failed struct se_cmd
1975 	 */
1976 	if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
1977 		transport_complete_task_attr(cmd);
1978 
1979 	if (complete) {
1980 		transport_direct_request_timeout(cmd);
1981 		cmd->transport_error_status = PYX_TRANSPORT_LU_COMM_FAILURE;
1982 	}
1983 
1984 	switch (cmd->transport_error_status) {
1985 	case PYX_TRANSPORT_UNKNOWN_SAM_OPCODE:
1986 		cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1987 		break;
1988 	case PYX_TRANSPORT_REQ_TOO_MANY_SECTORS:
1989 		cmd->scsi_sense_reason = TCM_SECTOR_COUNT_TOO_MANY;
1990 		break;
1991 	case PYX_TRANSPORT_INVALID_CDB_FIELD:
1992 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
1993 		break;
1994 	case PYX_TRANSPORT_INVALID_PARAMETER_LIST:
1995 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1996 		break;
1997 	case PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES:
1998 		if (!sc)
1999 			transport_new_cmd_failure(cmd);
2000 		/*
2001 		 * Currently for PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES,
2002 		 * we force this session to fall back to session
2003 		 * recovery.
2004 		 */
2005 		cmd->se_tfo->fall_back_to_erl0(cmd->se_sess);
2006 		cmd->se_tfo->stop_session(cmd->se_sess, 0, 0);
2007 
2008 		goto check_stop;
2009 	case PYX_TRANSPORT_LU_COMM_FAILURE:
2010 	case PYX_TRANSPORT_ILLEGAL_REQUEST:
2011 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2012 		break;
2013 	case PYX_TRANSPORT_UNKNOWN_MODE_PAGE:
2014 		cmd->scsi_sense_reason = TCM_UNKNOWN_MODE_PAGE;
2015 		break;
2016 	case PYX_TRANSPORT_WRITE_PROTECTED:
2017 		cmd->scsi_sense_reason = TCM_WRITE_PROTECTED;
2018 		break;
2019 	case PYX_TRANSPORT_RESERVATION_CONFLICT:
2020 		/*
2021 		 * No SENSE Data payload for this case, set SCSI Status
2022 		 * and queue the response to $FABRIC_MOD.
2023 		 *
2024 		 * Uses linux/include/scsi/scsi.h SAM status codes defs
2025 		 */
2026 		cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
2027 		/*
2028 		 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
2029 		 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
2030 		 * CONFLICT STATUS.
2031 		 *
2032 		 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
2033 		 */
2034 		if (cmd->se_sess &&
2035 		    cmd->se_dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 2)
2036 			core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
2037 				cmd->orig_fe_lun, 0x2C,
2038 				ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
2039 
2040 		ret = cmd->se_tfo->queue_status(cmd);
2041 		if (ret == -EAGAIN)
2042 			goto queue_full;
2043 		goto check_stop;
2044 	case PYX_TRANSPORT_USE_SENSE_REASON:
2045 		/*
2046 		 * struct se_cmd->scsi_sense_reason already set
2047 		 */
2048 		break;
2049 	default:
2050 		pr_err("Unknown transport error for CDB 0x%02x: %d\n",
2051 			cmd->t_task_cdb[0],
2052 			cmd->transport_error_status);
2053 		cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
2054 		break;
2055 	}
2056 
2057 	if (!sc)
2058 		transport_new_cmd_failure(cmd);
2059 	else {
2060 		ret = transport_send_check_condition_and_sense(cmd,
2061 				cmd->scsi_sense_reason, 0);
2062 		if (ret == -EAGAIN)
2063 			goto queue_full;
2064 	}
2065 
2066 check_stop:
2067 	transport_lun_remove_cmd(cmd);
2068 	if (!transport_cmd_check_stop_to_fabric(cmd))
2069 		;
2070 	return;
2071 
2072 queue_full:
2073 	cmd->t_state = TRANSPORT_COMPLETE_OK;
2074 	transport_handle_queue_full(cmd, cmd->se_dev, transport_complete_qf);
2075 }
2076 
2077 static void transport_direct_request_timeout(struct se_cmd *cmd)
2078 {
2079 	unsigned long flags;
2080 
2081 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2082 	if (!atomic_read(&cmd->t_transport_timeout)) {
2083 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2084 		return;
2085 	}
2086 	if (atomic_read(&cmd->t_task_cdbs_timeout_left)) {
2087 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2088 		return;
2089 	}
2090 
2091 	atomic_sub(atomic_read(&cmd->t_transport_timeout),
2092 		   &cmd->t_se_count);
2093 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2094 }
2095 
2096 static void transport_generic_request_timeout(struct se_cmd *cmd)
2097 {
2098 	unsigned long flags;
2099 
2100 	/*
2101 	 * Reset cmd->t_se_count to allow transport_generic_remove()
2102 	 * to allow last call to free memory resources.
2103 	 */
2104 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2105 	if (atomic_read(&cmd->t_transport_timeout) > 1) {
2106 		int tmp = (atomic_read(&cmd->t_transport_timeout) - 1);
2107 
2108 		atomic_sub(tmp, &cmd->t_se_count);
2109 	}
2110 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2111 
2112 	transport_generic_remove(cmd, 0);
2113 }
2114 
2115 static inline u32 transport_lba_21(unsigned char *cdb)
2116 {
2117 	return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
2118 }
2119 
2120 static inline u32 transport_lba_32(unsigned char *cdb)
2121 {
2122 	return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
2123 }
2124 
2125 static inline unsigned long long transport_lba_64(unsigned char *cdb)
2126 {
2127 	unsigned int __v1, __v2;
2128 
2129 	__v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
2130 	__v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
2131 
2132 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
2133 }
2134 
2135 /*
2136  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
2137  */
2138 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
2139 {
2140 	unsigned int __v1, __v2;
2141 
2142 	__v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
2143 	__v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
2144 
2145 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
2146 }
2147 
2148 static void transport_set_supported_SAM_opcode(struct se_cmd *se_cmd)
2149 {
2150 	unsigned long flags;
2151 
2152 	spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2153 	se_cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
2154 	spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2155 }
2156 
2157 /*
2158  * Called from interrupt context.
2159  */
2160 static void transport_task_timeout_handler(unsigned long data)
2161 {
2162 	struct se_task *task = (struct se_task *)data;
2163 	struct se_cmd *cmd = task->task_se_cmd;
2164 	unsigned long flags;
2165 
2166 	pr_debug("transport task timeout fired! task: %p cmd: %p\n", task, cmd);
2167 
2168 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2169 	if (task->task_flags & TF_STOP) {
2170 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2171 		return;
2172 	}
2173 	task->task_flags &= ~TF_RUNNING;
2174 
2175 	/*
2176 	 * Determine if transport_complete_task() has already been called.
2177 	 */
2178 	if (!atomic_read(&task->task_active)) {
2179 		pr_debug("transport task: %p cmd: %p timeout task_active"
2180 				" == 0\n", task, cmd);
2181 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2182 		return;
2183 	}
2184 
2185 	atomic_inc(&cmd->t_se_count);
2186 	atomic_inc(&cmd->t_transport_timeout);
2187 	cmd->t_tasks_failed = 1;
2188 
2189 	atomic_set(&task->task_timeout, 1);
2190 	task->task_error_status = PYX_TRANSPORT_TASK_TIMEOUT;
2191 	task->task_scsi_status = 1;
2192 
2193 	if (atomic_read(&task->task_stop)) {
2194 		pr_debug("transport task: %p cmd: %p timeout task_stop"
2195 				" == 1\n", task, cmd);
2196 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2197 		complete(&task->task_stop_comp);
2198 		return;
2199 	}
2200 
2201 	if (!atomic_dec_and_test(&cmd->t_task_cdbs_left)) {
2202 		pr_debug("transport task: %p cmd: %p timeout non zero"
2203 				" t_task_cdbs_left\n", task, cmd);
2204 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2205 		return;
2206 	}
2207 	pr_debug("transport task: %p cmd: %p timeout ZERO t_task_cdbs_left\n",
2208 			task, cmd);
2209 
2210 	cmd->t_state = TRANSPORT_COMPLETE_FAILURE;
2211 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2212 
2213 	transport_add_cmd_to_queue(cmd, TRANSPORT_COMPLETE_FAILURE);
2214 }
2215 
2216 /*
2217  * Called with cmd->t_state_lock held.
2218  */
2219 static void transport_start_task_timer(struct se_task *task)
2220 {
2221 	struct se_device *dev = task->se_dev;
2222 	int timeout;
2223 
2224 	if (task->task_flags & TF_RUNNING)
2225 		return;
2226 	/*
2227 	 * If the task_timeout is disabled, exit now.
2228 	 */
2229 	timeout = dev->se_sub_dev->se_dev_attrib.task_timeout;
2230 	if (!timeout)
2231 		return;
2232 
2233 	init_timer(&task->task_timer);
2234 	task->task_timer.expires = (get_jiffies_64() + timeout * HZ);
2235 	task->task_timer.data = (unsigned long) task;
2236 	task->task_timer.function = transport_task_timeout_handler;
2237 
2238 	task->task_flags |= TF_RUNNING;
2239 	add_timer(&task->task_timer);
2240 #if 0
2241 	pr_debug("Starting task timer for cmd: %p task: %p seconds:"
2242 		" %d\n", task->task_se_cmd, task, timeout);
2243 #endif
2244 }
2245 
2246 /*
2247  * Called with spin_lock_irq(&cmd->t_state_lock) held.
2248  */
2249 void __transport_stop_task_timer(struct se_task *task, unsigned long *flags)
2250 {
2251 	struct se_cmd *cmd = task->task_se_cmd;
2252 
2253 	if (!task->task_flags & TF_RUNNING)
2254 		return;
2255 
2256 	task->task_flags |= TF_STOP;
2257 	spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2258 
2259 	del_timer_sync(&task->task_timer);
2260 
2261 	spin_lock_irqsave(&cmd->t_state_lock, *flags);
2262 	task->task_flags &= ~TF_RUNNING;
2263 	task->task_flags &= ~TF_STOP;
2264 }
2265 
2266 static void transport_stop_all_task_timers(struct se_cmd *cmd)
2267 {
2268 	struct se_task *task = NULL, *task_tmp;
2269 	unsigned long flags;
2270 
2271 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2272 	list_for_each_entry_safe(task, task_tmp,
2273 				&cmd->t_task_list, t_list)
2274 		__transport_stop_task_timer(task, &flags);
2275 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2276 }
2277 
2278 static inline int transport_tcq_window_closed(struct se_device *dev)
2279 {
2280 	if (dev->dev_tcq_window_closed++ <
2281 			PYX_TRANSPORT_WINDOW_CLOSED_THRESHOLD) {
2282 		msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_SHORT);
2283 	} else
2284 		msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_LONG);
2285 
2286 	wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
2287 	return 0;
2288 }
2289 
2290 /*
2291  * Called from Fabric Module context from transport_execute_tasks()
2292  *
2293  * The return of this function determins if the tasks from struct se_cmd
2294  * get added to the execution queue in transport_execute_tasks(),
2295  * or are added to the delayed or ordered lists here.
2296  */
2297 static inline int transport_execute_task_attr(struct se_cmd *cmd)
2298 {
2299 	if (cmd->se_dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED)
2300 		return 1;
2301 	/*
2302 	 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
2303 	 * to allow the passed struct se_cmd list of tasks to the front of the list.
2304 	 */
2305 	 if (cmd->sam_task_attr == MSG_HEAD_TAG) {
2306 		atomic_inc(&cmd->se_dev->dev_hoq_count);
2307 		smp_mb__after_atomic_inc();
2308 		pr_debug("Added HEAD_OF_QUEUE for CDB:"
2309 			" 0x%02x, se_ordered_id: %u\n",
2310 			cmd->t_task_cdb[0],
2311 			cmd->se_ordered_id);
2312 		return 1;
2313 	} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
2314 		spin_lock(&cmd->se_dev->ordered_cmd_lock);
2315 		list_add_tail(&cmd->se_ordered_node,
2316 				&cmd->se_dev->ordered_cmd_list);
2317 		spin_unlock(&cmd->se_dev->ordered_cmd_lock);
2318 
2319 		atomic_inc(&cmd->se_dev->dev_ordered_sync);
2320 		smp_mb__after_atomic_inc();
2321 
2322 		pr_debug("Added ORDERED for CDB: 0x%02x to ordered"
2323 				" list, se_ordered_id: %u\n",
2324 				cmd->t_task_cdb[0],
2325 				cmd->se_ordered_id);
2326 		/*
2327 		 * Add ORDERED command to tail of execution queue if
2328 		 * no other older commands exist that need to be
2329 		 * completed first.
2330 		 */
2331 		if (!atomic_read(&cmd->se_dev->simple_cmds))
2332 			return 1;
2333 	} else {
2334 		/*
2335 		 * For SIMPLE and UNTAGGED Task Attribute commands
2336 		 */
2337 		atomic_inc(&cmd->se_dev->simple_cmds);
2338 		smp_mb__after_atomic_inc();
2339 	}
2340 	/*
2341 	 * Otherwise if one or more outstanding ORDERED task attribute exist,
2342 	 * add the dormant task(s) built for the passed struct se_cmd to the
2343 	 * execution queue and become in Active state for this struct se_device.
2344 	 */
2345 	if (atomic_read(&cmd->se_dev->dev_ordered_sync) != 0) {
2346 		/*
2347 		 * Otherwise, add cmd w/ tasks to delayed cmd queue that
2348 		 * will be drained upon completion of HEAD_OF_QUEUE task.
2349 		 */
2350 		spin_lock(&cmd->se_dev->delayed_cmd_lock);
2351 		cmd->se_cmd_flags |= SCF_DELAYED_CMD_FROM_SAM_ATTR;
2352 		list_add_tail(&cmd->se_delayed_node,
2353 				&cmd->se_dev->delayed_cmd_list);
2354 		spin_unlock(&cmd->se_dev->delayed_cmd_lock);
2355 
2356 		pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
2357 			" delayed CMD list, se_ordered_id: %u\n",
2358 			cmd->t_task_cdb[0], cmd->sam_task_attr,
2359 			cmd->se_ordered_id);
2360 		/*
2361 		 * Return zero to let transport_execute_tasks() know
2362 		 * not to add the delayed tasks to the execution list.
2363 		 */
2364 		return 0;
2365 	}
2366 	/*
2367 	 * Otherwise, no ORDERED task attributes exist..
2368 	 */
2369 	return 1;
2370 }
2371 
2372 /*
2373  * Called from fabric module context in transport_generic_new_cmd() and
2374  * transport_generic_process_write()
2375  */
2376 static int transport_execute_tasks(struct se_cmd *cmd)
2377 {
2378 	int add_tasks;
2379 
2380 	if (se_dev_check_online(cmd->se_orig_obj_ptr) != 0) {
2381 		cmd->transport_error_status = PYX_TRANSPORT_LU_COMM_FAILURE;
2382 		transport_generic_request_failure(cmd, NULL, 0, 1);
2383 		return 0;
2384 	}
2385 
2386 	/*
2387 	 * Call transport_cmd_check_stop() to see if a fabric exception
2388 	 * has occurred that prevents execution.
2389 	 */
2390 	if (!transport_cmd_check_stop(cmd, 0, TRANSPORT_PROCESSING)) {
2391 		/*
2392 		 * Check for SAM Task Attribute emulation and HEAD_OF_QUEUE
2393 		 * attribute for the tasks of the received struct se_cmd CDB
2394 		 */
2395 		add_tasks = transport_execute_task_attr(cmd);
2396 		if (!add_tasks)
2397 			goto execute_tasks;
2398 		/*
2399 		 * This calls transport_add_tasks_from_cmd() to handle
2400 		 * HEAD_OF_QUEUE ordering for SAM Task Attribute emulation
2401 		 * (if enabled) in __transport_add_task_to_execute_queue() and
2402 		 * transport_add_task_check_sam_attr().
2403 		 */
2404 		transport_add_tasks_from_cmd(cmd);
2405 	}
2406 	/*
2407 	 * Kick the execution queue for the cmd associated struct se_device
2408 	 * storage object.
2409 	 */
2410 execute_tasks:
2411 	__transport_execute_tasks(cmd->se_dev);
2412 	return 0;
2413 }
2414 
2415 /*
2416  * Called to check struct se_device tcq depth window, and once open pull struct se_task
2417  * from struct se_device->execute_task_list and
2418  *
2419  * Called from transport_processing_thread()
2420  */
2421 static int __transport_execute_tasks(struct se_device *dev)
2422 {
2423 	int error;
2424 	struct se_cmd *cmd = NULL;
2425 	struct se_task *task = NULL;
2426 	unsigned long flags;
2427 
2428 	/*
2429 	 * Check if there is enough room in the device and HBA queue to send
2430 	 * struct se_tasks to the selected transport.
2431 	 */
2432 check_depth:
2433 	if (!atomic_read(&dev->depth_left))
2434 		return transport_tcq_window_closed(dev);
2435 
2436 	dev->dev_tcq_window_closed = 0;
2437 
2438 	spin_lock_irq(&dev->execute_task_lock);
2439 	if (list_empty(&dev->execute_task_list)) {
2440 		spin_unlock_irq(&dev->execute_task_lock);
2441 		return 0;
2442 	}
2443 	task = list_first_entry(&dev->execute_task_list,
2444 				struct se_task, t_execute_list);
2445 	list_del(&task->t_execute_list);
2446 	atomic_set(&task->task_execute_queue, 0);
2447 	atomic_dec(&dev->execute_tasks);
2448 	spin_unlock_irq(&dev->execute_task_lock);
2449 
2450 	atomic_dec(&dev->depth_left);
2451 
2452 	cmd = task->task_se_cmd;
2453 
2454 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2455 	atomic_set(&task->task_active, 1);
2456 	atomic_set(&task->task_sent, 1);
2457 	atomic_inc(&cmd->t_task_cdbs_sent);
2458 
2459 	if (atomic_read(&cmd->t_task_cdbs_sent) ==
2460 	    cmd->t_task_list_num)
2461 		atomic_set(&cmd->transport_sent, 1);
2462 
2463 	transport_start_task_timer(task);
2464 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2465 	/*
2466 	 * The struct se_cmd->transport_emulate_cdb() function pointer is used
2467 	 * to grab REPORT_LUNS and other CDBs we want to handle before they hit the
2468 	 * struct se_subsystem_api->do_task() caller below.
2469 	 */
2470 	if (cmd->transport_emulate_cdb) {
2471 		error = cmd->transport_emulate_cdb(cmd);
2472 		if (error != 0) {
2473 			cmd->transport_error_status = error;
2474 			atomic_set(&task->task_active, 0);
2475 			atomic_set(&cmd->transport_sent, 0);
2476 			transport_stop_tasks_for_cmd(cmd);
2477 			transport_generic_request_failure(cmd, dev, 0, 1);
2478 			goto check_depth;
2479 		}
2480 		/*
2481 		 * Handle the successful completion for transport_emulate_cdb()
2482 		 * for synchronous operation, following SCF_EMULATE_CDB_ASYNC
2483 		 * Otherwise the caller is expected to complete the task with
2484 		 * proper status.
2485 		 */
2486 		if (!(cmd->se_cmd_flags & SCF_EMULATE_CDB_ASYNC)) {
2487 			cmd->scsi_status = SAM_STAT_GOOD;
2488 			task->task_scsi_status = GOOD;
2489 			transport_complete_task(task, 1);
2490 		}
2491 	} else {
2492 		/*
2493 		 * Currently for all virtual TCM plugins including IBLOCK, FILEIO and
2494 		 * RAMDISK we use the internal transport_emulate_control_cdb() logic
2495 		 * with struct se_subsystem_api callers for the primary SPC-3 TYPE_DISK
2496 		 * LUN emulation code.
2497 		 *
2498 		 * For TCM/pSCSI and all other SCF_SCSI_DATA_SG_IO_CDB I/O tasks we
2499 		 * call ->do_task() directly and let the underlying TCM subsystem plugin
2500 		 * code handle the CDB emulation.
2501 		 */
2502 		if ((dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) &&
2503 		    (!(task->task_se_cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)))
2504 			error = transport_emulate_control_cdb(task);
2505 		else
2506 			error = dev->transport->do_task(task);
2507 
2508 		if (error != 0) {
2509 			cmd->transport_error_status = error;
2510 			atomic_set(&task->task_active, 0);
2511 			atomic_set(&cmd->transport_sent, 0);
2512 			transport_stop_tasks_for_cmd(cmd);
2513 			transport_generic_request_failure(cmd, dev, 0, 1);
2514 		}
2515 	}
2516 
2517 	goto check_depth;
2518 
2519 	return 0;
2520 }
2521 
2522 void transport_new_cmd_failure(struct se_cmd *se_cmd)
2523 {
2524 	unsigned long flags;
2525 	/*
2526 	 * Any unsolicited data will get dumped for failed command inside of
2527 	 * the fabric plugin
2528 	 */
2529 	spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2530 	se_cmd->se_cmd_flags |= SCF_SE_CMD_FAILED;
2531 	se_cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2532 	spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2533 }
2534 
2535 static void transport_nop_wait_for_tasks(struct se_cmd *, int, int);
2536 
2537 static inline u32 transport_get_sectors_6(
2538 	unsigned char *cdb,
2539 	struct se_cmd *cmd,
2540 	int *ret)
2541 {
2542 	struct se_device *dev = cmd->se_dev;
2543 
2544 	/*
2545 	 * Assume TYPE_DISK for non struct se_device objects.
2546 	 * Use 8-bit sector value.
2547 	 */
2548 	if (!dev)
2549 		goto type_disk;
2550 
2551 	/*
2552 	 * Use 24-bit allocation length for TYPE_TAPE.
2553 	 */
2554 	if (dev->transport->get_device_type(dev) == TYPE_TAPE)
2555 		return (u32)(cdb[2] << 16) + (cdb[3] << 8) + cdb[4];
2556 
2557 	/*
2558 	 * Everything else assume TYPE_DISK Sector CDB location.
2559 	 * Use 8-bit sector value.
2560 	 */
2561 type_disk:
2562 	return (u32)cdb[4];
2563 }
2564 
2565 static inline u32 transport_get_sectors_10(
2566 	unsigned char *cdb,
2567 	struct se_cmd *cmd,
2568 	int *ret)
2569 {
2570 	struct se_device *dev = cmd->se_dev;
2571 
2572 	/*
2573 	 * Assume TYPE_DISK for non struct se_device objects.
2574 	 * Use 16-bit sector value.
2575 	 */
2576 	if (!dev)
2577 		goto type_disk;
2578 
2579 	/*
2580 	 * XXX_10 is not defined in SSC, throw an exception
2581 	 */
2582 	if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2583 		*ret = -EINVAL;
2584 		return 0;
2585 	}
2586 
2587 	/*
2588 	 * Everything else assume TYPE_DISK Sector CDB location.
2589 	 * Use 16-bit sector value.
2590 	 */
2591 type_disk:
2592 	return (u32)(cdb[7] << 8) + cdb[8];
2593 }
2594 
2595 static inline u32 transport_get_sectors_12(
2596 	unsigned char *cdb,
2597 	struct se_cmd *cmd,
2598 	int *ret)
2599 {
2600 	struct se_device *dev = cmd->se_dev;
2601 
2602 	/*
2603 	 * Assume TYPE_DISK for non struct se_device objects.
2604 	 * Use 32-bit sector value.
2605 	 */
2606 	if (!dev)
2607 		goto type_disk;
2608 
2609 	/*
2610 	 * XXX_12 is not defined in SSC, throw an exception
2611 	 */
2612 	if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2613 		*ret = -EINVAL;
2614 		return 0;
2615 	}
2616 
2617 	/*
2618 	 * Everything else assume TYPE_DISK Sector CDB location.
2619 	 * Use 32-bit sector value.
2620 	 */
2621 type_disk:
2622 	return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
2623 }
2624 
2625 static inline u32 transport_get_sectors_16(
2626 	unsigned char *cdb,
2627 	struct se_cmd *cmd,
2628 	int *ret)
2629 {
2630 	struct se_device *dev = cmd->se_dev;
2631 
2632 	/*
2633 	 * Assume TYPE_DISK for non struct se_device objects.
2634 	 * Use 32-bit sector value.
2635 	 */
2636 	if (!dev)
2637 		goto type_disk;
2638 
2639 	/*
2640 	 * Use 24-bit allocation length for TYPE_TAPE.
2641 	 */
2642 	if (dev->transport->get_device_type(dev) == TYPE_TAPE)
2643 		return (u32)(cdb[12] << 16) + (cdb[13] << 8) + cdb[14];
2644 
2645 type_disk:
2646 	return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
2647 		    (cdb[12] << 8) + cdb[13];
2648 }
2649 
2650 /*
2651  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
2652  */
2653 static inline u32 transport_get_sectors_32(
2654 	unsigned char *cdb,
2655 	struct se_cmd *cmd,
2656 	int *ret)
2657 {
2658 	/*
2659 	 * Assume TYPE_DISK for non struct se_device objects.
2660 	 * Use 32-bit sector value.
2661 	 */
2662 	return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
2663 		    (cdb[30] << 8) + cdb[31];
2664 
2665 }
2666 
2667 static inline u32 transport_get_size(
2668 	u32 sectors,
2669 	unsigned char *cdb,
2670 	struct se_cmd *cmd)
2671 {
2672 	struct se_device *dev = cmd->se_dev;
2673 
2674 	if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2675 		if (cdb[1] & 1) { /* sectors */
2676 			return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
2677 		} else /* bytes */
2678 			return sectors;
2679 	}
2680 #if 0
2681 	pr_debug("Returning block_size: %u, sectors: %u == %u for"
2682 			" %s object\n", dev->se_sub_dev->se_dev_attrib.block_size, sectors,
2683 			dev->se_sub_dev->se_dev_attrib.block_size * sectors,
2684 			dev->transport->name);
2685 #endif
2686 	return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
2687 }
2688 
2689 static void transport_xor_callback(struct se_cmd *cmd)
2690 {
2691 	unsigned char *buf, *addr;
2692 	struct scatterlist *sg;
2693 	unsigned int offset;
2694 	int i;
2695 	int count;
2696 	/*
2697 	 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
2698 	 *
2699 	 * 1) read the specified logical block(s);
2700 	 * 2) transfer logical blocks from the data-out buffer;
2701 	 * 3) XOR the logical blocks transferred from the data-out buffer with
2702 	 *    the logical blocks read, storing the resulting XOR data in a buffer;
2703 	 * 4) if the DISABLE WRITE bit is set to zero, then write the logical
2704 	 *    blocks transferred from the data-out buffer; and
2705 	 * 5) transfer the resulting XOR data to the data-in buffer.
2706 	 */
2707 	buf = kmalloc(cmd->data_length, GFP_KERNEL);
2708 	if (!buf) {
2709 		pr_err("Unable to allocate xor_callback buf\n");
2710 		return;
2711 	}
2712 	/*
2713 	 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
2714 	 * into the locally allocated *buf
2715 	 */
2716 	sg_copy_to_buffer(cmd->t_data_sg,
2717 			  cmd->t_data_nents,
2718 			  buf,
2719 			  cmd->data_length);
2720 
2721 	/*
2722 	 * Now perform the XOR against the BIDI read memory located at
2723 	 * cmd->t_mem_bidi_list
2724 	 */
2725 
2726 	offset = 0;
2727 	for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
2728 		addr = kmap_atomic(sg_page(sg), KM_USER0);
2729 		if (!addr)
2730 			goto out;
2731 
2732 		for (i = 0; i < sg->length; i++)
2733 			*(addr + sg->offset + i) ^= *(buf + offset + i);
2734 
2735 		offset += sg->length;
2736 		kunmap_atomic(addr, KM_USER0);
2737 	}
2738 
2739 out:
2740 	kfree(buf);
2741 }
2742 
2743 /*
2744  * Used to obtain Sense Data from underlying Linux/SCSI struct scsi_cmnd
2745  */
2746 static int transport_get_sense_data(struct se_cmd *cmd)
2747 {
2748 	unsigned char *buffer = cmd->sense_buffer, *sense_buffer = NULL;
2749 	struct se_device *dev;
2750 	struct se_task *task = NULL, *task_tmp;
2751 	unsigned long flags;
2752 	u32 offset = 0;
2753 
2754 	WARN_ON(!cmd->se_lun);
2755 
2756 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2757 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2758 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2759 		return 0;
2760 	}
2761 
2762 	list_for_each_entry_safe(task, task_tmp,
2763 				&cmd->t_task_list, t_list) {
2764 
2765 		if (!task->task_sense)
2766 			continue;
2767 
2768 		dev = task->se_dev;
2769 		if (!dev)
2770 			continue;
2771 
2772 		if (!dev->transport->get_sense_buffer) {
2773 			pr_err("dev->transport->get_sense_buffer"
2774 					" is NULL\n");
2775 			continue;
2776 		}
2777 
2778 		sense_buffer = dev->transport->get_sense_buffer(task);
2779 		if (!sense_buffer) {
2780 			pr_err("ITT[0x%08x]_TASK[%d]: Unable to locate"
2781 				" sense buffer for task with sense\n",
2782 				cmd->se_tfo->get_task_tag(cmd), task->task_no);
2783 			continue;
2784 		}
2785 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2786 
2787 		offset = cmd->se_tfo->set_fabric_sense_len(cmd,
2788 				TRANSPORT_SENSE_BUFFER);
2789 
2790 		memcpy(&buffer[offset], sense_buffer,
2791 				TRANSPORT_SENSE_BUFFER);
2792 		cmd->scsi_status = task->task_scsi_status;
2793 		/* Automatically padded */
2794 		cmd->scsi_sense_length =
2795 				(TRANSPORT_SENSE_BUFFER + offset);
2796 
2797 		pr_debug("HBA_[%u]_PLUG[%s]: Set SAM STATUS: 0x%02x"
2798 				" and sense\n",
2799 			dev->se_hba->hba_id, dev->transport->name,
2800 				cmd->scsi_status);
2801 		return 0;
2802 	}
2803 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2804 
2805 	return -1;
2806 }
2807 
2808 static int
2809 transport_handle_reservation_conflict(struct se_cmd *cmd)
2810 {
2811 	cmd->transport_wait_for_tasks = &transport_nop_wait_for_tasks;
2812 	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2813 	cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT;
2814 	cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
2815 	/*
2816 	 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
2817 	 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
2818 	 * CONFLICT STATUS.
2819 	 *
2820 	 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
2821 	 */
2822 	if (cmd->se_sess &&
2823 	    cmd->se_dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 2)
2824 		core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
2825 			cmd->orig_fe_lun, 0x2C,
2826 			ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
2827 	return -EINVAL;
2828 }
2829 
2830 static inline long long transport_dev_end_lba(struct se_device *dev)
2831 {
2832 	return dev->transport->get_blocks(dev) + 1;
2833 }
2834 
2835 static int transport_cmd_get_valid_sectors(struct se_cmd *cmd)
2836 {
2837 	struct se_device *dev = cmd->se_dev;
2838 	u32 sectors;
2839 
2840 	if (dev->transport->get_device_type(dev) != TYPE_DISK)
2841 		return 0;
2842 
2843 	sectors = (cmd->data_length / dev->se_sub_dev->se_dev_attrib.block_size);
2844 
2845 	if ((cmd->t_task_lba + sectors) > transport_dev_end_lba(dev)) {
2846 		pr_err("LBA: %llu Sectors: %u exceeds"
2847 			" transport_dev_end_lba(): %llu\n",
2848 			cmd->t_task_lba, sectors,
2849 			transport_dev_end_lba(dev));
2850 		pr_err("  We should return CHECK_CONDITION"
2851 		       " but we don't yet\n");
2852 		return 0;
2853 	}
2854 
2855 	return sectors;
2856 }
2857 
2858 /*	transport_generic_cmd_sequencer():
2859  *
2860  *	Generic Command Sequencer that should work for most DAS transport
2861  *	drivers.
2862  *
2863  *	Called from transport_generic_allocate_tasks() in the $FABRIC_MOD
2864  *	RX Thread.
2865  *
2866  *	FIXME: Need to support other SCSI OPCODES where as well.
2867  */
2868 static int transport_generic_cmd_sequencer(
2869 	struct se_cmd *cmd,
2870 	unsigned char *cdb)
2871 {
2872 	struct se_device *dev = cmd->se_dev;
2873 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
2874 	int ret = 0, sector_ret = 0, passthrough;
2875 	u32 sectors = 0, size = 0, pr_reg_type = 0;
2876 	u16 service_action;
2877 	u8 alua_ascq = 0;
2878 	/*
2879 	 * Check for an existing UNIT ATTENTION condition
2880 	 */
2881 	if (core_scsi3_ua_check(cmd, cdb) < 0) {
2882 		cmd->transport_wait_for_tasks =
2883 				&transport_nop_wait_for_tasks;
2884 		cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2885 		cmd->scsi_sense_reason = TCM_CHECK_CONDITION_UNIT_ATTENTION;
2886 		return -EINVAL;
2887 	}
2888 	/*
2889 	 * Check status of Asymmetric Logical Unit Assignment port
2890 	 */
2891 	ret = su_dev->t10_alua.alua_state_check(cmd, cdb, &alua_ascq);
2892 	if (ret != 0) {
2893 		cmd->transport_wait_for_tasks = &transport_nop_wait_for_tasks;
2894 		/*
2895 		 * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
2896 		 * The ALUA additional sense code qualifier (ASCQ) is determined
2897 		 * by the ALUA primary or secondary access state..
2898 		 */
2899 		if (ret > 0) {
2900 #if 0
2901 			pr_debug("[%s]: ALUA TG Port not available,"
2902 				" SenseKey: NOT_READY, ASC/ASCQ: 0x04/0x%02x\n",
2903 				cmd->se_tfo->get_fabric_name(), alua_ascq);
2904 #endif
2905 			transport_set_sense_codes(cmd, 0x04, alua_ascq);
2906 			cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2907 			cmd->scsi_sense_reason = TCM_CHECK_CONDITION_NOT_READY;
2908 			return -EINVAL;
2909 		}
2910 		goto out_invalid_cdb_field;
2911 	}
2912 	/*
2913 	 * Check status for SPC-3 Persistent Reservations
2914 	 */
2915 	if (su_dev->t10_pr.pr_ops.t10_reservation_check(cmd, &pr_reg_type) != 0) {
2916 		if (su_dev->t10_pr.pr_ops.t10_seq_non_holder(
2917 					cmd, cdb, pr_reg_type) != 0)
2918 			return transport_handle_reservation_conflict(cmd);
2919 		/*
2920 		 * This means the CDB is allowed for the SCSI Initiator port
2921 		 * when said port is *NOT* holding the legacy SPC-2 or
2922 		 * SPC-3 Persistent Reservation.
2923 		 */
2924 	}
2925 
2926 	switch (cdb[0]) {
2927 	case READ_6:
2928 		sectors = transport_get_sectors_6(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_6;
2933 		cmd->t_task_lba = transport_lba_21(cdb);
2934 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2935 		break;
2936 	case READ_10:
2937 		sectors = transport_get_sectors_10(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_10;
2942 		cmd->t_task_lba = transport_lba_32(cdb);
2943 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2944 		break;
2945 	case READ_12:
2946 		sectors = transport_get_sectors_12(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_12;
2951 		cmd->t_task_lba = transport_lba_32(cdb);
2952 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2953 		break;
2954 	case READ_16:
2955 		sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2956 		if (sector_ret)
2957 			goto out_unsupported_cdb;
2958 		size = transport_get_size(sectors, cdb, cmd);
2959 		cmd->transport_split_cdb = &split_cdb_XX_16;
2960 		cmd->t_task_lba = transport_lba_64(cdb);
2961 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2962 		break;
2963 	case WRITE_6:
2964 		sectors = transport_get_sectors_6(cdb, cmd, &sector_ret);
2965 		if (sector_ret)
2966 			goto out_unsupported_cdb;
2967 		size = transport_get_size(sectors, cdb, cmd);
2968 		cmd->transport_split_cdb = &split_cdb_XX_6;
2969 		cmd->t_task_lba = transport_lba_21(cdb);
2970 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2971 		break;
2972 	case WRITE_10:
2973 		sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2974 		if (sector_ret)
2975 			goto out_unsupported_cdb;
2976 		size = transport_get_size(sectors, cdb, cmd);
2977 		cmd->transport_split_cdb = &split_cdb_XX_10;
2978 		cmd->t_task_lba = transport_lba_32(cdb);
2979 		cmd->t_tasks_fua = (cdb[1] & 0x8);
2980 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2981 		break;
2982 	case WRITE_12:
2983 		sectors = transport_get_sectors_12(cdb, cmd, &sector_ret);
2984 		if (sector_ret)
2985 			goto out_unsupported_cdb;
2986 		size = transport_get_size(sectors, cdb, cmd);
2987 		cmd->transport_split_cdb = &split_cdb_XX_12;
2988 		cmd->t_task_lba = transport_lba_32(cdb);
2989 		cmd->t_tasks_fua = (cdb[1] & 0x8);
2990 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2991 		break;
2992 	case WRITE_16:
2993 		sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2994 		if (sector_ret)
2995 			goto out_unsupported_cdb;
2996 		size = transport_get_size(sectors, cdb, cmd);
2997 		cmd->transport_split_cdb = &split_cdb_XX_16;
2998 		cmd->t_task_lba = transport_lba_64(cdb);
2999 		cmd->t_tasks_fua = (cdb[1] & 0x8);
3000 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
3001 		break;
3002 	case XDWRITEREAD_10:
3003 		if ((cmd->data_direction != DMA_TO_DEVICE) ||
3004 		    !(cmd->t_tasks_bidi))
3005 			goto out_invalid_cdb_field;
3006 		sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
3007 		if (sector_ret)
3008 			goto out_unsupported_cdb;
3009 		size = transport_get_size(sectors, cdb, cmd);
3010 		cmd->transport_split_cdb = &split_cdb_XX_10;
3011 		cmd->t_task_lba = transport_lba_32(cdb);
3012 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
3013 		passthrough = (dev->transport->transport_type ==
3014 				TRANSPORT_PLUGIN_PHBA_PDEV);
3015 		/*
3016 		 * Skip the remaining assignments for TCM/PSCSI passthrough
3017 		 */
3018 		if (passthrough)
3019 			break;
3020 		/*
3021 		 * Setup BIDI XOR callback to be run during transport_generic_complete_ok()
3022 		 */
3023 		cmd->transport_complete_callback = &transport_xor_callback;
3024 		cmd->t_tasks_fua = (cdb[1] & 0x8);
3025 		break;
3026 	case VARIABLE_LENGTH_CMD:
3027 		service_action = get_unaligned_be16(&cdb[8]);
3028 		/*
3029 		 * Determine if this is TCM/PSCSI device and we should disable
3030 		 * internal emulation for this CDB.
3031 		 */
3032 		passthrough = (dev->transport->transport_type ==
3033 					TRANSPORT_PLUGIN_PHBA_PDEV);
3034 
3035 		switch (service_action) {
3036 		case XDWRITEREAD_32:
3037 			sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
3038 			if (sector_ret)
3039 				goto out_unsupported_cdb;
3040 			size = transport_get_size(sectors, cdb, cmd);
3041 			/*
3042 			 * Use WRITE_32 and READ_32 opcodes for the emulated
3043 			 * XDWRITE_READ_32 logic.
3044 			 */
3045 			cmd->transport_split_cdb = &split_cdb_XX_32;
3046 			cmd->t_task_lba = transport_lba_64_ext(cdb);
3047 			cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
3048 
3049 			/*
3050 			 * Skip the remaining assignments for TCM/PSCSI passthrough
3051 			 */
3052 			if (passthrough)
3053 				break;
3054 
3055 			/*
3056 			 * Setup BIDI XOR callback to be run during
3057 			 * transport_generic_complete_ok()
3058 			 */
3059 			cmd->transport_complete_callback = &transport_xor_callback;
3060 			cmd->t_tasks_fua = (cdb[10] & 0x8);
3061 			break;
3062 		case WRITE_SAME_32:
3063 			sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
3064 			if (sector_ret)
3065 				goto out_unsupported_cdb;
3066 
3067 			if (sectors)
3068 				size = transport_get_size(sectors, cdb, cmd);
3069 			else {
3070 				pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
3071 				       " supported\n");
3072 				goto out_invalid_cdb_field;
3073 			}
3074 
3075 			cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
3076 			cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3077 
3078 			/*
3079 			 * Skip the remaining assignments for TCM/PSCSI passthrough
3080 			 */
3081 			if (passthrough)
3082 				break;
3083 
3084 			if ((cdb[10] & 0x04) || (cdb[10] & 0x02)) {
3085 				pr_err("WRITE_SAME PBDATA and LBDATA"
3086 					" bits not supported for Block Discard"
3087 					" Emulation\n");
3088 				goto out_invalid_cdb_field;
3089 			}
3090 			/*
3091 			 * Currently for the emulated case we only accept
3092 			 * tpws with the UNMAP=1 bit set.
3093 			 */
3094 			if (!(cdb[10] & 0x08)) {
3095 				pr_err("WRITE_SAME w/o UNMAP bit not"
3096 					" supported for Block Discard Emulation\n");
3097 				goto out_invalid_cdb_field;
3098 			}
3099 			break;
3100 		default:
3101 			pr_err("VARIABLE_LENGTH_CMD service action"
3102 				" 0x%04x not supported\n", service_action);
3103 			goto out_unsupported_cdb;
3104 		}
3105 		break;
3106 	case MAINTENANCE_IN:
3107 		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
3108 			/* MAINTENANCE_IN from SCC-2 */
3109 			/*
3110 			 * Check for emulated MI_REPORT_TARGET_PGS.
3111 			 */
3112 			if (cdb[1] == MI_REPORT_TARGET_PGS) {
3113 				cmd->transport_emulate_cdb =
3114 				(su_dev->t10_alua.alua_type ==
3115 				 SPC3_ALUA_EMULATED) ?
3116 				core_emulate_report_target_port_groups :
3117 				NULL;
3118 			}
3119 			size = (cdb[6] << 24) | (cdb[7] << 16) |
3120 			       (cdb[8] << 8) | cdb[9];
3121 		} else {
3122 			/* GPCMD_SEND_KEY from multi media commands */
3123 			size = (cdb[8] << 8) + cdb[9];
3124 		}
3125 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3126 		break;
3127 	case MODE_SELECT:
3128 		size = cdb[4];
3129 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3130 		break;
3131 	case MODE_SELECT_10:
3132 		size = (cdb[7] << 8) + cdb[8];
3133 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3134 		break;
3135 	case MODE_SENSE:
3136 		size = cdb[4];
3137 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3138 		break;
3139 	case MODE_SENSE_10:
3140 	case GPCMD_READ_BUFFER_CAPACITY:
3141 	case GPCMD_SEND_OPC:
3142 	case LOG_SELECT:
3143 	case LOG_SENSE:
3144 		size = (cdb[7] << 8) + cdb[8];
3145 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3146 		break;
3147 	case READ_BLOCK_LIMITS:
3148 		size = READ_BLOCK_LEN;
3149 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3150 		break;
3151 	case GPCMD_GET_CONFIGURATION:
3152 	case GPCMD_READ_FORMAT_CAPACITIES:
3153 	case GPCMD_READ_DISC_INFO:
3154 	case GPCMD_READ_TRACK_RZONE_INFO:
3155 		size = (cdb[7] << 8) + cdb[8];
3156 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3157 		break;
3158 	case PERSISTENT_RESERVE_IN:
3159 	case PERSISTENT_RESERVE_OUT:
3160 		cmd->transport_emulate_cdb =
3161 			(su_dev->t10_pr.res_type ==
3162 			 SPC3_PERSISTENT_RESERVATIONS) ?
3163 			core_scsi3_emulate_pr : NULL;
3164 		size = (cdb[7] << 8) + cdb[8];
3165 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3166 		break;
3167 	case GPCMD_MECHANISM_STATUS:
3168 	case GPCMD_READ_DVD_STRUCTURE:
3169 		size = (cdb[8] << 8) + cdb[9];
3170 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3171 		break;
3172 	case READ_POSITION:
3173 		size = READ_POSITION_LEN;
3174 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3175 		break;
3176 	case MAINTENANCE_OUT:
3177 		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
3178 			/* MAINTENANCE_OUT from SCC-2
3179 			 *
3180 			 * Check for emulated MO_SET_TARGET_PGS.
3181 			 */
3182 			if (cdb[1] == MO_SET_TARGET_PGS) {
3183 				cmd->transport_emulate_cdb =
3184 				(su_dev->t10_alua.alua_type ==
3185 					SPC3_ALUA_EMULATED) ?
3186 				core_emulate_set_target_port_groups :
3187 				NULL;
3188 			}
3189 
3190 			size = (cdb[6] << 24) | (cdb[7] << 16) |
3191 			       (cdb[8] << 8) | cdb[9];
3192 		} else  {
3193 			/* GPCMD_REPORT_KEY from multi media commands */
3194 			size = (cdb[8] << 8) + cdb[9];
3195 		}
3196 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3197 		break;
3198 	case INQUIRY:
3199 		size = (cdb[3] << 8) + cdb[4];
3200 		/*
3201 		 * Do implict HEAD_OF_QUEUE processing for INQUIRY.
3202 		 * See spc4r17 section 5.3
3203 		 */
3204 		if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3205 			cmd->sam_task_attr = MSG_HEAD_TAG;
3206 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3207 		break;
3208 	case READ_BUFFER:
3209 		size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
3210 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3211 		break;
3212 	case READ_CAPACITY:
3213 		size = READ_CAP_LEN;
3214 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3215 		break;
3216 	case READ_MEDIA_SERIAL_NUMBER:
3217 	case SECURITY_PROTOCOL_IN:
3218 	case SECURITY_PROTOCOL_OUT:
3219 		size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
3220 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3221 		break;
3222 	case SERVICE_ACTION_IN:
3223 	case ACCESS_CONTROL_IN:
3224 	case ACCESS_CONTROL_OUT:
3225 	case EXTENDED_COPY:
3226 	case READ_ATTRIBUTE:
3227 	case RECEIVE_COPY_RESULTS:
3228 	case WRITE_ATTRIBUTE:
3229 		size = (cdb[10] << 24) | (cdb[11] << 16) |
3230 		       (cdb[12] << 8) | cdb[13];
3231 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3232 		break;
3233 	case RECEIVE_DIAGNOSTIC:
3234 	case SEND_DIAGNOSTIC:
3235 		size = (cdb[3] << 8) | cdb[4];
3236 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3237 		break;
3238 /* #warning FIXME: Figure out correct GPCMD_READ_CD blocksize. */
3239 #if 0
3240 	case GPCMD_READ_CD:
3241 		sectors = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
3242 		size = (2336 * sectors);
3243 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3244 		break;
3245 #endif
3246 	case READ_TOC:
3247 		size = cdb[8];
3248 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3249 		break;
3250 	case REQUEST_SENSE:
3251 		size = cdb[4];
3252 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3253 		break;
3254 	case READ_ELEMENT_STATUS:
3255 		size = 65536 * cdb[7] + 256 * cdb[8] + cdb[9];
3256 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3257 		break;
3258 	case WRITE_BUFFER:
3259 		size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
3260 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3261 		break;
3262 	case RESERVE:
3263 	case RESERVE_10:
3264 		/*
3265 		 * The SPC-2 RESERVE does not contain a size in the SCSI CDB.
3266 		 * Assume the passthrough or $FABRIC_MOD will tell us about it.
3267 		 */
3268 		if (cdb[0] == RESERVE_10)
3269 			size = (cdb[7] << 8) | cdb[8];
3270 		else
3271 			size = cmd->data_length;
3272 
3273 		/*
3274 		 * Setup the legacy emulated handler for SPC-2 and
3275 		 * >= SPC-3 compatible reservation handling (CRH=1)
3276 		 * Otherwise, we assume the underlying SCSI logic is
3277 		 * is running in SPC_PASSTHROUGH, and wants reservations
3278 		 * emulation disabled.
3279 		 */
3280 		cmd->transport_emulate_cdb =
3281 				(su_dev->t10_pr.res_type !=
3282 				 SPC_PASSTHROUGH) ?
3283 				core_scsi2_emulate_crh : NULL;
3284 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3285 		break;
3286 	case RELEASE:
3287 	case RELEASE_10:
3288 		/*
3289 		 * The SPC-2 RELEASE does not contain a size in the SCSI CDB.
3290 		 * Assume the passthrough or $FABRIC_MOD will tell us about it.
3291 		*/
3292 		if (cdb[0] == RELEASE_10)
3293 			size = (cdb[7] << 8) | cdb[8];
3294 		else
3295 			size = cmd->data_length;
3296 
3297 		cmd->transport_emulate_cdb =
3298 				(su_dev->t10_pr.res_type !=
3299 				 SPC_PASSTHROUGH) ?
3300 				core_scsi2_emulate_crh : NULL;
3301 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3302 		break;
3303 	case SYNCHRONIZE_CACHE:
3304 	case 0x91: /* SYNCHRONIZE_CACHE_16: */
3305 		/*
3306 		 * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
3307 		 */
3308 		if (cdb[0] == SYNCHRONIZE_CACHE) {
3309 			sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
3310 			cmd->t_task_lba = transport_lba_32(cdb);
3311 		} else {
3312 			sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
3313 			cmd->t_task_lba = transport_lba_64(cdb);
3314 		}
3315 		if (sector_ret)
3316 			goto out_unsupported_cdb;
3317 
3318 		size = transport_get_size(sectors, cdb, cmd);
3319 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3320 
3321 		/*
3322 		 * For TCM/pSCSI passthrough, skip cmd->transport_emulate_cdb()
3323 		 */
3324 		if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
3325 			break;
3326 		/*
3327 		 * Set SCF_EMULATE_CDB_ASYNC to ensure asynchronous operation
3328 		 * for SYNCHRONIZE_CACHE* Immed=1 case in __transport_execute_tasks()
3329 		 */
3330 		cmd->se_cmd_flags |= SCF_EMULATE_CDB_ASYNC;
3331 		/*
3332 		 * Check to ensure that LBA + Range does not exceed past end of
3333 		 * device.
3334 		 */
3335 		if (!transport_cmd_get_valid_sectors(cmd))
3336 			goto out_invalid_cdb_field;
3337 		break;
3338 	case UNMAP:
3339 		size = get_unaligned_be16(&cdb[7]);
3340 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3341 		break;
3342 	case WRITE_SAME_16:
3343 		sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
3344 		if (sector_ret)
3345 			goto out_unsupported_cdb;
3346 
3347 		if (sectors)
3348 			size = transport_get_size(sectors, cdb, cmd);
3349 		else {
3350 			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
3351 			goto out_invalid_cdb_field;
3352 		}
3353 
3354 		cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
3355 		passthrough = (dev->transport->transport_type ==
3356 				TRANSPORT_PLUGIN_PHBA_PDEV);
3357 		/*
3358 		 * Determine if the received WRITE_SAME_16 is used to for direct
3359 		 * passthrough into Linux/SCSI with struct request via TCM/pSCSI
3360 		 * or we are signaling the use of internal WRITE_SAME + UNMAP=1
3361 		 * emulation for -> Linux/BLOCK disbard with TCM/IBLOCK and
3362 		 * TCM/FILEIO subsystem plugin backstores.
3363 		 */
3364 		if (!passthrough) {
3365 			if ((cdb[1] & 0x04) || (cdb[1] & 0x02)) {
3366 				pr_err("WRITE_SAME PBDATA and LBDATA"
3367 					" bits not supported for Block Discard"
3368 					" Emulation\n");
3369 				goto out_invalid_cdb_field;
3370 			}
3371 			/*
3372 			 * Currently for the emulated case we only accept
3373 			 * tpws with the UNMAP=1 bit set.
3374 			 */
3375 			if (!(cdb[1] & 0x08)) {
3376 				pr_err("WRITE_SAME w/o UNMAP bit not "
3377 					" supported for Block Discard Emulation\n");
3378 				goto out_invalid_cdb_field;
3379 			}
3380 		}
3381 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3382 		break;
3383 	case ALLOW_MEDIUM_REMOVAL:
3384 	case GPCMD_CLOSE_TRACK:
3385 	case ERASE:
3386 	case INITIALIZE_ELEMENT_STATUS:
3387 	case GPCMD_LOAD_UNLOAD:
3388 	case REZERO_UNIT:
3389 	case SEEK_10:
3390 	case GPCMD_SET_SPEED:
3391 	case SPACE:
3392 	case START_STOP:
3393 	case TEST_UNIT_READY:
3394 	case VERIFY:
3395 	case WRITE_FILEMARKS:
3396 	case MOVE_MEDIUM:
3397 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3398 		break;
3399 	case REPORT_LUNS:
3400 		cmd->transport_emulate_cdb =
3401 				transport_core_report_lun_response;
3402 		size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
3403 		/*
3404 		 * Do implict HEAD_OF_QUEUE processing for REPORT_LUNS
3405 		 * See spc4r17 section 5.3
3406 		 */
3407 		if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3408 			cmd->sam_task_attr = MSG_HEAD_TAG;
3409 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3410 		break;
3411 	default:
3412 		pr_warn("TARGET_CORE[%s]: Unsupported SCSI Opcode"
3413 			" 0x%02x, sending CHECK_CONDITION.\n",
3414 			cmd->se_tfo->get_fabric_name(), cdb[0]);
3415 		cmd->transport_wait_for_tasks = &transport_nop_wait_for_tasks;
3416 		goto out_unsupported_cdb;
3417 	}
3418 
3419 	if (size != cmd->data_length) {
3420 		pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
3421 			" %u does not match SCSI CDB Length: %u for SAM Opcode:"
3422 			" 0x%02x\n", cmd->se_tfo->get_fabric_name(),
3423 				cmd->data_length, size, cdb[0]);
3424 
3425 		cmd->cmd_spdtl = size;
3426 
3427 		if (cmd->data_direction == DMA_TO_DEVICE) {
3428 			pr_err("Rejecting underflow/overflow"
3429 					" WRITE data\n");
3430 			goto out_invalid_cdb_field;
3431 		}
3432 		/*
3433 		 * Reject READ_* or WRITE_* with overflow/underflow for
3434 		 * type SCF_SCSI_DATA_SG_IO_CDB.
3435 		 */
3436 		if (!ret && (dev->se_sub_dev->se_dev_attrib.block_size != 512))  {
3437 			pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
3438 				" CDB on non 512-byte sector setup subsystem"
3439 				" plugin: %s\n", dev->transport->name);
3440 			/* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
3441 			goto out_invalid_cdb_field;
3442 		}
3443 
3444 		if (size > cmd->data_length) {
3445 			cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
3446 			cmd->residual_count = (size - cmd->data_length);
3447 		} else {
3448 			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
3449 			cmd->residual_count = (cmd->data_length - size);
3450 		}
3451 		cmd->data_length = size;
3452 	}
3453 
3454 	/* Let's limit control cdbs to a page, for simplicity's sake. */
3455 	if ((cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) &&
3456 	    size > PAGE_SIZE)
3457 		goto out_invalid_cdb_field;
3458 
3459 	transport_set_supported_SAM_opcode(cmd);
3460 	return ret;
3461 
3462 out_unsupported_cdb:
3463 	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3464 	cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
3465 	return -EINVAL;
3466 out_invalid_cdb_field:
3467 	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3468 	cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3469 	return -EINVAL;
3470 }
3471 
3472 /*
3473  * Called from transport_generic_complete_ok() and
3474  * transport_generic_request_failure() to determine which dormant/delayed
3475  * and ordered cmds need to have their tasks added to the execution queue.
3476  */
3477 static void transport_complete_task_attr(struct se_cmd *cmd)
3478 {
3479 	struct se_device *dev = cmd->se_dev;
3480 	struct se_cmd *cmd_p, *cmd_tmp;
3481 	int new_active_tasks = 0;
3482 
3483 	if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
3484 		atomic_dec(&dev->simple_cmds);
3485 		smp_mb__after_atomic_dec();
3486 		dev->dev_cur_ordered_id++;
3487 		pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
3488 			" SIMPLE: %u\n", dev->dev_cur_ordered_id,
3489 			cmd->se_ordered_id);
3490 	} else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
3491 		atomic_dec(&dev->dev_hoq_count);
3492 		smp_mb__after_atomic_dec();
3493 		dev->dev_cur_ordered_id++;
3494 		pr_debug("Incremented dev_cur_ordered_id: %u for"
3495 			" HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
3496 			cmd->se_ordered_id);
3497 	} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
3498 		spin_lock(&dev->ordered_cmd_lock);
3499 		list_del(&cmd->se_ordered_node);
3500 		atomic_dec(&dev->dev_ordered_sync);
3501 		smp_mb__after_atomic_dec();
3502 		spin_unlock(&dev->ordered_cmd_lock);
3503 
3504 		dev->dev_cur_ordered_id++;
3505 		pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
3506 			" %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
3507 	}
3508 	/*
3509 	 * Process all commands up to the last received
3510 	 * ORDERED task attribute which requires another blocking
3511 	 * boundary
3512 	 */
3513 	spin_lock(&dev->delayed_cmd_lock);
3514 	list_for_each_entry_safe(cmd_p, cmd_tmp,
3515 			&dev->delayed_cmd_list, se_delayed_node) {
3516 
3517 		list_del(&cmd_p->se_delayed_node);
3518 		spin_unlock(&dev->delayed_cmd_lock);
3519 
3520 		pr_debug("Calling add_tasks() for"
3521 			" cmd_p: 0x%02x Task Attr: 0x%02x"
3522 			" Dormant -> Active, se_ordered_id: %u\n",
3523 			cmd_p->t_task_cdb[0],
3524 			cmd_p->sam_task_attr, cmd_p->se_ordered_id);
3525 
3526 		transport_add_tasks_from_cmd(cmd_p);
3527 		new_active_tasks++;
3528 
3529 		spin_lock(&dev->delayed_cmd_lock);
3530 		if (cmd_p->sam_task_attr == MSG_ORDERED_TAG)
3531 			break;
3532 	}
3533 	spin_unlock(&dev->delayed_cmd_lock);
3534 	/*
3535 	 * If new tasks have become active, wake up the transport thread
3536 	 * to do the processing of the Active tasks.
3537 	 */
3538 	if (new_active_tasks != 0)
3539 		wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
3540 }
3541 
3542 static int transport_complete_qf(struct se_cmd *cmd)
3543 {
3544 	int ret = 0;
3545 
3546 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
3547 		return cmd->se_tfo->queue_status(cmd);
3548 
3549 	switch (cmd->data_direction) {
3550 	case DMA_FROM_DEVICE:
3551 		ret = cmd->se_tfo->queue_data_in(cmd);
3552 		break;
3553 	case DMA_TO_DEVICE:
3554 		if (cmd->t_bidi_data_sg) {
3555 			ret = cmd->se_tfo->queue_data_in(cmd);
3556 			if (ret < 0)
3557 				return ret;
3558 		}
3559 		/* Fall through for DMA_TO_DEVICE */
3560 	case DMA_NONE:
3561 		ret = cmd->se_tfo->queue_status(cmd);
3562 		break;
3563 	default:
3564 		break;
3565 	}
3566 
3567 	return ret;
3568 }
3569 
3570 static void transport_handle_queue_full(
3571 	struct se_cmd *cmd,
3572 	struct se_device *dev,
3573 	int (*qf_callback)(struct se_cmd *))
3574 {
3575 	spin_lock_irq(&dev->qf_cmd_lock);
3576 	cmd->se_cmd_flags |= SCF_EMULATE_QUEUE_FULL;
3577 	cmd->transport_qf_callback = qf_callback;
3578 	list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
3579 	atomic_inc(&dev->dev_qf_count);
3580 	smp_mb__after_atomic_inc();
3581 	spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
3582 
3583 	schedule_work(&cmd->se_dev->qf_work_queue);
3584 }
3585 
3586 static void transport_generic_complete_ok(struct se_cmd *cmd)
3587 {
3588 	int reason = 0, ret;
3589 	/*
3590 	 * Check if we need to move delayed/dormant tasks from cmds on the
3591 	 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
3592 	 * Attribute.
3593 	 */
3594 	if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3595 		transport_complete_task_attr(cmd);
3596 	/*
3597 	 * Check to schedule QUEUE_FULL work, or execute an existing
3598 	 * cmd->transport_qf_callback()
3599 	 */
3600 	if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
3601 		schedule_work(&cmd->se_dev->qf_work_queue);
3602 
3603 	if (cmd->transport_qf_callback) {
3604 		ret = cmd->transport_qf_callback(cmd);
3605 		if (ret < 0)
3606 			goto queue_full;
3607 
3608 		cmd->transport_qf_callback = NULL;
3609 		goto done;
3610 	}
3611 	/*
3612 	 * Check if we need to retrieve a sense buffer from
3613 	 * the struct se_cmd in question.
3614 	 */
3615 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
3616 		if (transport_get_sense_data(cmd) < 0)
3617 			reason = TCM_NON_EXISTENT_LUN;
3618 
3619 		/*
3620 		 * Only set when an struct se_task->task_scsi_status returned
3621 		 * a non GOOD status.
3622 		 */
3623 		if (cmd->scsi_status) {
3624 			ret = transport_send_check_condition_and_sense(
3625 					cmd, reason, 1);
3626 			if (ret == -EAGAIN)
3627 				goto queue_full;
3628 
3629 			transport_lun_remove_cmd(cmd);
3630 			transport_cmd_check_stop_to_fabric(cmd);
3631 			return;
3632 		}
3633 	}
3634 	/*
3635 	 * Check for a callback, used by amongst other things
3636 	 * XDWRITE_READ_10 emulation.
3637 	 */
3638 	if (cmd->transport_complete_callback)
3639 		cmd->transport_complete_callback(cmd);
3640 
3641 	switch (cmd->data_direction) {
3642 	case DMA_FROM_DEVICE:
3643 		spin_lock(&cmd->se_lun->lun_sep_lock);
3644 		if (cmd->se_lun->lun_sep) {
3645 			cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
3646 					cmd->data_length;
3647 		}
3648 		spin_unlock(&cmd->se_lun->lun_sep_lock);
3649 
3650 		ret = cmd->se_tfo->queue_data_in(cmd);
3651 		if (ret == -EAGAIN)
3652 			goto queue_full;
3653 		break;
3654 	case DMA_TO_DEVICE:
3655 		spin_lock(&cmd->se_lun->lun_sep_lock);
3656 		if (cmd->se_lun->lun_sep) {
3657 			cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
3658 				cmd->data_length;
3659 		}
3660 		spin_unlock(&cmd->se_lun->lun_sep_lock);
3661 		/*
3662 		 * Check if we need to send READ payload for BIDI-COMMAND
3663 		 */
3664 		if (cmd->t_bidi_data_sg) {
3665 			spin_lock(&cmd->se_lun->lun_sep_lock);
3666 			if (cmd->se_lun->lun_sep) {
3667 				cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
3668 					cmd->data_length;
3669 			}
3670 			spin_unlock(&cmd->se_lun->lun_sep_lock);
3671 			ret = cmd->se_tfo->queue_data_in(cmd);
3672 			if (ret == -EAGAIN)
3673 				goto queue_full;
3674 			break;
3675 		}
3676 		/* Fall through for DMA_TO_DEVICE */
3677 	case DMA_NONE:
3678 		ret = cmd->se_tfo->queue_status(cmd);
3679 		if (ret == -EAGAIN)
3680 			goto queue_full;
3681 		break;
3682 	default:
3683 		break;
3684 	}
3685 
3686 done:
3687 	transport_lun_remove_cmd(cmd);
3688 	transport_cmd_check_stop_to_fabric(cmd);
3689 	return;
3690 
3691 queue_full:
3692 	pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
3693 		" data_direction: %d\n", cmd, cmd->data_direction);
3694 	transport_handle_queue_full(cmd, cmd->se_dev, transport_complete_qf);
3695 }
3696 
3697 static void transport_free_dev_tasks(struct se_cmd *cmd)
3698 {
3699 	struct se_task *task, *task_tmp;
3700 	unsigned long flags;
3701 
3702 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3703 	list_for_each_entry_safe(task, task_tmp,
3704 				&cmd->t_task_list, t_list) {
3705 		if (atomic_read(&task->task_active))
3706 			continue;
3707 
3708 		kfree(task->task_sg_bidi);
3709 		kfree(task->task_sg);
3710 
3711 		list_del(&task->t_list);
3712 
3713 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3714 		if (task->se_dev)
3715 			task->se_dev->transport->free_task(task);
3716 		else
3717 			pr_err("task[%u] - task->se_dev is NULL\n",
3718 				task->task_no);
3719 		spin_lock_irqsave(&cmd->t_state_lock, flags);
3720 	}
3721 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3722 }
3723 
3724 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
3725 {
3726 	struct scatterlist *sg;
3727 	int count;
3728 
3729 	for_each_sg(sgl, sg, nents, count)
3730 		__free_page(sg_page(sg));
3731 
3732 	kfree(sgl);
3733 }
3734 
3735 static inline void transport_free_pages(struct se_cmd *cmd)
3736 {
3737 	if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
3738 		return;
3739 
3740 	transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
3741 	cmd->t_data_sg = NULL;
3742 	cmd->t_data_nents = 0;
3743 
3744 	transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
3745 	cmd->t_bidi_data_sg = NULL;
3746 	cmd->t_bidi_data_nents = 0;
3747 }
3748 
3749 static inline void transport_release_tasks(struct se_cmd *cmd)
3750 {
3751 	transport_free_dev_tasks(cmd);
3752 }
3753 
3754 static inline int transport_dec_and_check(struct se_cmd *cmd)
3755 {
3756 	unsigned long flags;
3757 
3758 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3759 	if (atomic_read(&cmd->t_fe_count)) {
3760 		if (!atomic_dec_and_test(&cmd->t_fe_count)) {
3761 			spin_unlock_irqrestore(&cmd->t_state_lock,
3762 					flags);
3763 			return 1;
3764 		}
3765 	}
3766 
3767 	if (atomic_read(&cmd->t_se_count)) {
3768 		if (!atomic_dec_and_test(&cmd->t_se_count)) {
3769 			spin_unlock_irqrestore(&cmd->t_state_lock,
3770 					flags);
3771 			return 1;
3772 		}
3773 	}
3774 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3775 
3776 	return 0;
3777 }
3778 
3779 static void transport_release_fe_cmd(struct se_cmd *cmd)
3780 {
3781 	unsigned long flags;
3782 
3783 	if (transport_dec_and_check(cmd))
3784 		return;
3785 
3786 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3787 	if (!atomic_read(&cmd->transport_dev_active)) {
3788 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3789 		goto free_pages;
3790 	}
3791 	atomic_set(&cmd->transport_dev_active, 0);
3792 	transport_all_task_dev_remove_state(cmd);
3793 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3794 
3795 	transport_release_tasks(cmd);
3796 free_pages:
3797 	transport_free_pages(cmd);
3798 	transport_free_se_cmd(cmd);
3799 	cmd->se_tfo->release_cmd(cmd);
3800 }
3801 
3802 static int
3803 transport_generic_remove(struct se_cmd *cmd, int session_reinstatement)
3804 {
3805 	unsigned long flags;
3806 
3807 	if (transport_dec_and_check(cmd)) {
3808 		if (session_reinstatement) {
3809 			spin_lock_irqsave(&cmd->t_state_lock, flags);
3810 			transport_all_task_dev_remove_state(cmd);
3811 			spin_unlock_irqrestore(&cmd->t_state_lock,
3812 					flags);
3813 		}
3814 		return 1;
3815 	}
3816 
3817 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3818 	if (!atomic_read(&cmd->transport_dev_active)) {
3819 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3820 		goto free_pages;
3821 	}
3822 	atomic_set(&cmd->transport_dev_active, 0);
3823 	transport_all_task_dev_remove_state(cmd);
3824 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3825 
3826 	transport_release_tasks(cmd);
3827 
3828 free_pages:
3829 	transport_free_pages(cmd);
3830 	transport_release_cmd(cmd);
3831 	return 0;
3832 }
3833 
3834 /*
3835  * transport_generic_map_mem_to_cmd - Use fabric-alloced pages instead of
3836  * allocating in the core.
3837  * @cmd:  Associated se_cmd descriptor
3838  * @mem:  SGL style memory for TCM WRITE / READ
3839  * @sg_mem_num: Number of SGL elements
3840  * @mem_bidi_in: SGL style memory for TCM BIDI READ
3841  * @sg_mem_bidi_num: Number of BIDI READ SGL elements
3842  *
3843  * Return: nonzero return cmd was rejected for -ENOMEM or inproper usage
3844  * of parameters.
3845  */
3846 int transport_generic_map_mem_to_cmd(
3847 	struct se_cmd *cmd,
3848 	struct scatterlist *sgl,
3849 	u32 sgl_count,
3850 	struct scatterlist *sgl_bidi,
3851 	u32 sgl_bidi_count)
3852 {
3853 	if (!sgl || !sgl_count)
3854 		return 0;
3855 
3856 	if ((cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) ||
3857 	    (cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB)) {
3858 
3859 		cmd->t_data_sg = sgl;
3860 		cmd->t_data_nents = sgl_count;
3861 
3862 		if (sgl_bidi && sgl_bidi_count) {
3863 			cmd->t_bidi_data_sg = sgl_bidi;
3864 			cmd->t_bidi_data_nents = sgl_bidi_count;
3865 		}
3866 		cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
3867 	}
3868 
3869 	return 0;
3870 }
3871 EXPORT_SYMBOL(transport_generic_map_mem_to_cmd);
3872 
3873 static int transport_new_cmd_obj(struct se_cmd *cmd)
3874 {
3875 	struct se_device *dev = cmd->se_dev;
3876 	u32 task_cdbs;
3877 	u32 rc;
3878 	int set_counts = 1;
3879 
3880 	/*
3881 	 * Setup any BIDI READ tasks and memory from
3882 	 * cmd->t_mem_bidi_list so the READ struct se_tasks
3883 	 * are queued first for the non pSCSI passthrough case.
3884 	 */
3885 	if (cmd->t_bidi_data_sg &&
3886 	    (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV)) {
3887 		rc = transport_allocate_tasks(cmd,
3888 					      cmd->t_task_lba,
3889 					      DMA_FROM_DEVICE,
3890 					      cmd->t_bidi_data_sg,
3891 					      cmd->t_bidi_data_nents);
3892 		if (rc <= 0) {
3893 			cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3894 			cmd->scsi_sense_reason =
3895 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3896 			return PYX_TRANSPORT_LU_COMM_FAILURE;
3897 		}
3898 		atomic_inc(&cmd->t_fe_count);
3899 		atomic_inc(&cmd->t_se_count);
3900 		set_counts = 0;
3901 	}
3902 	/*
3903 	 * Setup the tasks and memory from cmd->t_mem_list
3904 	 * Note for BIDI transfers this will contain the WRITE payload
3905 	 */
3906 	task_cdbs = transport_allocate_tasks(cmd,
3907 					     cmd->t_task_lba,
3908 					     cmd->data_direction,
3909 					     cmd->t_data_sg,
3910 					     cmd->t_data_nents);
3911 	if (task_cdbs <= 0) {
3912 		cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3913 		cmd->scsi_sense_reason =
3914 			TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3915 		return PYX_TRANSPORT_LU_COMM_FAILURE;
3916 	}
3917 
3918 	if (set_counts) {
3919 		atomic_inc(&cmd->t_fe_count);
3920 		atomic_inc(&cmd->t_se_count);
3921 	}
3922 
3923 	cmd->t_task_list_num = task_cdbs;
3924 
3925 	atomic_set(&cmd->t_task_cdbs_left, task_cdbs);
3926 	atomic_set(&cmd->t_task_cdbs_ex_left, task_cdbs);
3927 	atomic_set(&cmd->t_task_cdbs_timeout_left, task_cdbs);
3928 	return 0;
3929 }
3930 
3931 void *transport_kmap_first_data_page(struct se_cmd *cmd)
3932 {
3933 	struct scatterlist *sg = cmd->t_data_sg;
3934 
3935 	BUG_ON(!sg);
3936 	/*
3937 	 * We need to take into account a possible offset here for fabrics like
3938 	 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
3939 	 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
3940 	 */
3941 	return kmap(sg_page(sg)) + sg->offset;
3942 }
3943 EXPORT_SYMBOL(transport_kmap_first_data_page);
3944 
3945 void transport_kunmap_first_data_page(struct se_cmd *cmd)
3946 {
3947 	kunmap(sg_page(cmd->t_data_sg));
3948 }
3949 EXPORT_SYMBOL(transport_kunmap_first_data_page);
3950 
3951 static int
3952 transport_generic_get_mem(struct se_cmd *cmd)
3953 {
3954 	u32 length = cmd->data_length;
3955 	unsigned int nents;
3956 	struct page *page;
3957 	int i = 0;
3958 
3959 	nents = DIV_ROUND_UP(length, PAGE_SIZE);
3960 	cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
3961 	if (!cmd->t_data_sg)
3962 		return -ENOMEM;
3963 
3964 	cmd->t_data_nents = nents;
3965 	sg_init_table(cmd->t_data_sg, nents);
3966 
3967 	while (length) {
3968 		u32 page_len = min_t(u32, length, PAGE_SIZE);
3969 		page = alloc_page(GFP_KERNEL | __GFP_ZERO);
3970 		if (!page)
3971 			goto out;
3972 
3973 		sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
3974 		length -= page_len;
3975 		i++;
3976 	}
3977 	return 0;
3978 
3979 out:
3980 	while (i >= 0) {
3981 		__free_page(sg_page(&cmd->t_data_sg[i]));
3982 		i--;
3983 	}
3984 	kfree(cmd->t_data_sg);
3985 	cmd->t_data_sg = NULL;
3986 	return -ENOMEM;
3987 }
3988 
3989 /* Reduce sectors if they are too long for the device */
3990 static inline sector_t transport_limit_task_sectors(
3991 	struct se_device *dev,
3992 	unsigned long long lba,
3993 	sector_t sectors)
3994 {
3995 	sectors = min_t(sector_t, sectors, dev->se_sub_dev->se_dev_attrib.max_sectors);
3996 
3997 	if (dev->transport->get_device_type(dev) == TYPE_DISK)
3998 		if ((lba + sectors) > transport_dev_end_lba(dev))
3999 			sectors = ((transport_dev_end_lba(dev) - lba) + 1);
4000 
4001 	return sectors;
4002 }
4003 
4004 
4005 /*
4006  * This function can be used by HW target mode drivers to create a linked
4007  * scatterlist from all contiguously allocated struct se_task->task_sg[].
4008  * This is intended to be called during the completion path by TCM Core
4009  * when struct target_core_fabric_ops->check_task_sg_chaining is enabled.
4010  */
4011 void transport_do_task_sg_chain(struct se_cmd *cmd)
4012 {
4013 	struct scatterlist *sg_first = NULL;
4014 	struct scatterlist *sg_prev = NULL;
4015 	int sg_prev_nents = 0;
4016 	struct scatterlist *sg;
4017 	struct se_task *task;
4018 	u32 chained_nents = 0;
4019 	int i;
4020 
4021 	BUG_ON(!cmd->se_tfo->task_sg_chaining);
4022 
4023 	/*
4024 	 * Walk the struct se_task list and setup scatterlist chains
4025 	 * for each contiguously allocated struct se_task->task_sg[].
4026 	 */
4027 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
4028 		if (!task->task_sg)
4029 			continue;
4030 
4031 		BUG_ON(!task->task_padded_sg);
4032 
4033 		if (!sg_first) {
4034 			sg_first = task->task_sg;
4035 			chained_nents = task->task_sg_nents;
4036 		} else {
4037 			sg_chain(sg_prev, sg_prev_nents, task->task_sg);
4038 			chained_nents += task->task_sg_nents;
4039 		}
4040 
4041 		sg_prev = task->task_sg;
4042 		sg_prev_nents = task->task_sg_nents;
4043 	}
4044 	/*
4045 	 * Setup the starting pointer and total t_tasks_sg_linked_no including
4046 	 * padding SGs for linking and to mark the end.
4047 	 */
4048 	cmd->t_tasks_sg_chained = sg_first;
4049 	cmd->t_tasks_sg_chained_no = chained_nents;
4050 
4051 	pr_debug("Setup cmd: %p cmd->t_tasks_sg_chained: %p and"
4052 		" t_tasks_sg_chained_no: %u\n", cmd, cmd->t_tasks_sg_chained,
4053 		cmd->t_tasks_sg_chained_no);
4054 
4055 	for_each_sg(cmd->t_tasks_sg_chained, sg,
4056 			cmd->t_tasks_sg_chained_no, i) {
4057 
4058 		pr_debug("SG[%d]: %p page: %p length: %d offset: %d\n",
4059 			i, sg, sg_page(sg), sg->length, sg->offset);
4060 		if (sg_is_chain(sg))
4061 			pr_debug("SG: %p sg_is_chain=1\n", sg);
4062 		if (sg_is_last(sg))
4063 			pr_debug("SG: %p sg_is_last=1\n", sg);
4064 	}
4065 }
4066 EXPORT_SYMBOL(transport_do_task_sg_chain);
4067 
4068 /*
4069  * Break up cmd into chunks transport can handle
4070  */
4071 static int transport_allocate_data_tasks(
4072 	struct se_cmd *cmd,
4073 	unsigned long long lba,
4074 	enum dma_data_direction data_direction,
4075 	struct scatterlist *sgl,
4076 	unsigned int sgl_nents)
4077 {
4078 	unsigned char *cdb = NULL;
4079 	struct se_task *task;
4080 	struct se_device *dev = cmd->se_dev;
4081 	unsigned long flags;
4082 	int task_count, i, ret;
4083 	sector_t sectors, dev_max_sectors = dev->se_sub_dev->se_dev_attrib.max_sectors;
4084 	u32 sector_size = dev->se_sub_dev->se_dev_attrib.block_size;
4085 	struct scatterlist *sg;
4086 	struct scatterlist *cmd_sg;
4087 
4088 	WARN_ON(cmd->data_length % sector_size);
4089 	sectors = DIV_ROUND_UP(cmd->data_length, sector_size);
4090 	task_count = DIV_ROUND_UP_SECTOR_T(sectors, dev_max_sectors);
4091 
4092 	cmd_sg = sgl;
4093 	for (i = 0; i < task_count; i++) {
4094 		unsigned int task_size;
4095 		int count;
4096 
4097 		task = transport_generic_get_task(cmd, data_direction);
4098 		if (!task)
4099 			return -ENOMEM;
4100 
4101 		task->task_lba = lba;
4102 		task->task_sectors = min(sectors, dev_max_sectors);
4103 		task->task_size = task->task_sectors * sector_size;
4104 
4105 		cdb = dev->transport->get_cdb(task);
4106 		BUG_ON(!cdb);
4107 
4108 		memcpy(cdb, cmd->t_task_cdb,
4109 		       scsi_command_size(cmd->t_task_cdb));
4110 
4111 		/* Update new cdb with updated lba/sectors */
4112 		cmd->transport_split_cdb(task->task_lba, task->task_sectors, cdb);
4113 
4114 		/*
4115 		 * Check if the fabric module driver is requesting that all
4116 		 * struct se_task->task_sg[] be chained together..  If so,
4117 		 * then allocate an extra padding SG entry for linking and
4118 		 * marking the end of the chained SGL.
4119 		 * Possibly over-allocate task sgl size by using cmd sgl size.
4120 		 * It's so much easier and only a waste when task_count > 1.
4121 		 * That is extremely rare.
4122 		 */
4123 		task->task_sg_nents = sgl_nents;
4124 		if (cmd->se_tfo->task_sg_chaining) {
4125 			task->task_sg_nents++;
4126 			task->task_padded_sg = 1;
4127 		}
4128 
4129 		task->task_sg = kmalloc(sizeof(struct scatterlist) *
4130 					task->task_sg_nents, GFP_KERNEL);
4131 		if (!task->task_sg) {
4132 			cmd->se_dev->transport->free_task(task);
4133 			return -ENOMEM;
4134 		}
4135 
4136 		sg_init_table(task->task_sg, task->task_sg_nents);
4137 
4138 		task_size = task->task_size;
4139 
4140 		/* Build new sgl, only up to task_size */
4141 		for_each_sg(task->task_sg, sg, task->task_sg_nents, count) {
4142 			if (cmd_sg->length > task_size)
4143 				break;
4144 
4145 			*sg = *cmd_sg;
4146 			task_size -= cmd_sg->length;
4147 			cmd_sg = sg_next(cmd_sg);
4148 		}
4149 
4150 		lba += task->task_sectors;
4151 		sectors -= task->task_sectors;
4152 
4153 		spin_lock_irqsave(&cmd->t_state_lock, flags);
4154 		list_add_tail(&task->t_list, &cmd->t_task_list);
4155 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4156 	}
4157 	/*
4158 	 * Now perform the memory map of task->task_sg[] into backend
4159 	 * subsystem memory..
4160 	 */
4161 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
4162 		if (atomic_read(&task->task_sent))
4163 			continue;
4164 		if (!dev->transport->map_data_SG)
4165 			continue;
4166 
4167 		ret = dev->transport->map_data_SG(task);
4168 		if (ret < 0)
4169 			return 0;
4170 	}
4171 
4172 	return task_count;
4173 }
4174 
4175 static int
4176 transport_allocate_control_task(struct se_cmd *cmd)
4177 {
4178 	struct se_device *dev = cmd->se_dev;
4179 	unsigned char *cdb;
4180 	struct se_task *task;
4181 	unsigned long flags;
4182 	int ret = 0;
4183 
4184 	task = transport_generic_get_task(cmd, cmd->data_direction);
4185 	if (!task)
4186 		return -ENOMEM;
4187 
4188 	cdb = dev->transport->get_cdb(task);
4189 	BUG_ON(!cdb);
4190 	memcpy(cdb, cmd->t_task_cdb,
4191 	       scsi_command_size(cmd->t_task_cdb));
4192 
4193 	task->task_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
4194 				GFP_KERNEL);
4195 	if (!task->task_sg) {
4196 		cmd->se_dev->transport->free_task(task);
4197 		return -ENOMEM;
4198 	}
4199 
4200 	memcpy(task->task_sg, cmd->t_data_sg,
4201 	       sizeof(struct scatterlist) * cmd->t_data_nents);
4202 	task->task_size = cmd->data_length;
4203 	task->task_sg_nents = cmd->t_data_nents;
4204 
4205 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4206 	list_add_tail(&task->t_list, &cmd->t_task_list);
4207 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4208 
4209 	if (cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) {
4210 		if (dev->transport->map_control_SG)
4211 			ret = dev->transport->map_control_SG(task);
4212 	} else if (cmd->se_cmd_flags & SCF_SCSI_NON_DATA_CDB) {
4213 		if (dev->transport->cdb_none)
4214 			ret = dev->transport->cdb_none(task);
4215 	} else {
4216 		pr_err("target: Unknown control cmd type!\n");
4217 		BUG();
4218 	}
4219 
4220 	/* Success! Return number of tasks allocated */
4221 	if (ret == 0)
4222 		return 1;
4223 	return ret;
4224 }
4225 
4226 static u32 transport_allocate_tasks(
4227 	struct se_cmd *cmd,
4228 	unsigned long long lba,
4229 	enum dma_data_direction data_direction,
4230 	struct scatterlist *sgl,
4231 	unsigned int sgl_nents)
4232 {
4233 	if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)
4234 		return transport_allocate_data_tasks(cmd, lba, data_direction,
4235 						     sgl, sgl_nents);
4236 	else
4237 		return transport_allocate_control_task(cmd);
4238 
4239 }
4240 
4241 
4242 /*	 transport_generic_new_cmd(): Called from transport_processing_thread()
4243  *
4244  *	 Allocate storage transport resources from a set of values predefined
4245  *	 by transport_generic_cmd_sequencer() from the iSCSI Target RX process.
4246  *	 Any non zero return here is treated as an "out of resource' op here.
4247  */
4248 	/*
4249 	 * Generate struct se_task(s) and/or their payloads for this CDB.
4250 	 */
4251 int transport_generic_new_cmd(struct se_cmd *cmd)
4252 {
4253 	int ret = 0;
4254 
4255 	/*
4256 	 * Determine is the TCM fabric module has already allocated physical
4257 	 * memory, and is directly calling transport_generic_map_mem_to_cmd()
4258 	 * beforehand.
4259 	 */
4260 	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
4261 	    cmd->data_length) {
4262 		ret = transport_generic_get_mem(cmd);
4263 		if (ret < 0)
4264 			return ret;
4265 	}
4266 	/*
4267 	 * Call transport_new_cmd_obj() to invoke transport_allocate_tasks() for
4268 	 * control or data CDB types, and perform the map to backend subsystem
4269 	 * code from SGL memory allocated here by transport_generic_get_mem(), or
4270 	 * via pre-existing SGL memory setup explictly by fabric module code with
4271 	 * transport_generic_map_mem_to_cmd().
4272 	 */
4273 	ret = transport_new_cmd_obj(cmd);
4274 	if (ret < 0)
4275 		return ret;
4276 	/*
4277 	 * For WRITEs, let the fabric know its buffer is ready..
4278 	 * This WRITE struct se_cmd (and all of its associated struct se_task's)
4279 	 * will be added to the struct se_device execution queue after its WRITE
4280 	 * data has arrived. (ie: It gets handled by the transport processing
4281 	 * thread a second time)
4282 	 */
4283 	if (cmd->data_direction == DMA_TO_DEVICE) {
4284 		transport_add_tasks_to_state_queue(cmd);
4285 		return transport_generic_write_pending(cmd);
4286 	}
4287 	/*
4288 	 * Everything else but a WRITE, add the struct se_cmd's struct se_task's
4289 	 * to the execution queue.
4290 	 */
4291 	transport_execute_tasks(cmd);
4292 	return 0;
4293 }
4294 EXPORT_SYMBOL(transport_generic_new_cmd);
4295 
4296 /*	transport_generic_process_write():
4297  *
4298  *
4299  */
4300 void transport_generic_process_write(struct se_cmd *cmd)
4301 {
4302 	transport_execute_tasks(cmd);
4303 }
4304 EXPORT_SYMBOL(transport_generic_process_write);
4305 
4306 static int transport_write_pending_qf(struct se_cmd *cmd)
4307 {
4308 	return cmd->se_tfo->write_pending(cmd);
4309 }
4310 
4311 /*	transport_generic_write_pending():
4312  *
4313  *
4314  */
4315 static int transport_generic_write_pending(struct se_cmd *cmd)
4316 {
4317 	unsigned long flags;
4318 	int ret;
4319 
4320 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4321 	cmd->t_state = TRANSPORT_WRITE_PENDING;
4322 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4323 
4324 	if (cmd->transport_qf_callback) {
4325 		ret = cmd->transport_qf_callback(cmd);
4326 		if (ret == -EAGAIN)
4327 			goto queue_full;
4328 		else if (ret < 0)
4329 			return ret;
4330 
4331 		cmd->transport_qf_callback = NULL;
4332 		return 0;
4333 	}
4334 
4335 	/*
4336 	 * Clear the se_cmd for WRITE_PENDING status in order to set
4337 	 * cmd->t_transport_active=0 so that transport_generic_handle_data
4338 	 * can be called from HW target mode interrupt code.  This is safe
4339 	 * to be called with transport_off=1 before the cmd->se_tfo->write_pending
4340 	 * because the se_cmd->se_lun pointer is not being cleared.
4341 	 */
4342 	transport_cmd_check_stop(cmd, 1, 0);
4343 
4344 	/*
4345 	 * Call the fabric write_pending function here to let the
4346 	 * frontend know that WRITE buffers are ready.
4347 	 */
4348 	ret = cmd->se_tfo->write_pending(cmd);
4349 	if (ret == -EAGAIN)
4350 		goto queue_full;
4351 	else if (ret < 0)
4352 		return ret;
4353 
4354 	return PYX_TRANSPORT_WRITE_PENDING;
4355 
4356 queue_full:
4357 	pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
4358 	cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
4359 	transport_handle_queue_full(cmd, cmd->se_dev,
4360 			transport_write_pending_qf);
4361 	return ret;
4362 }
4363 
4364 void transport_release_cmd(struct se_cmd *cmd)
4365 {
4366 	BUG_ON(!cmd->se_tfo);
4367 
4368 	transport_free_se_cmd(cmd);
4369 	cmd->se_tfo->release_cmd(cmd);
4370 }
4371 EXPORT_SYMBOL(transport_release_cmd);
4372 
4373 /*	transport_generic_free_cmd():
4374  *
4375  *	Called from processing frontend to release storage engine resources
4376  */
4377 void transport_generic_free_cmd(
4378 	struct se_cmd *cmd,
4379 	int wait_for_tasks,
4380 	int session_reinstatement)
4381 {
4382 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD))
4383 		transport_release_cmd(cmd);
4384 	else {
4385 		core_dec_lacl_count(cmd->se_sess->se_node_acl, cmd);
4386 
4387 		if (cmd->se_lun) {
4388 #if 0
4389 			pr_debug("cmd: %p ITT: 0x%08x contains"
4390 				" cmd->se_lun\n", cmd,
4391 				cmd->se_tfo->get_task_tag(cmd));
4392 #endif
4393 			transport_lun_remove_cmd(cmd);
4394 		}
4395 
4396 		if (wait_for_tasks && cmd->transport_wait_for_tasks)
4397 			cmd->transport_wait_for_tasks(cmd, 0, 0);
4398 
4399 		transport_free_dev_tasks(cmd);
4400 
4401 		transport_generic_remove(cmd, session_reinstatement);
4402 	}
4403 }
4404 EXPORT_SYMBOL(transport_generic_free_cmd);
4405 
4406 static void transport_nop_wait_for_tasks(
4407 	struct se_cmd *cmd,
4408 	int remove_cmd,
4409 	int session_reinstatement)
4410 {
4411 	return;
4412 }
4413 
4414 /*	transport_lun_wait_for_tasks():
4415  *
4416  *	Called from ConfigFS context to stop the passed struct se_cmd to allow
4417  *	an struct se_lun to be successfully shutdown.
4418  */
4419 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
4420 {
4421 	unsigned long flags;
4422 	int ret;
4423 	/*
4424 	 * If the frontend has already requested this struct se_cmd to
4425 	 * be stopped, we can safely ignore this struct se_cmd.
4426 	 */
4427 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4428 	if (atomic_read(&cmd->t_transport_stop)) {
4429 		atomic_set(&cmd->transport_lun_stop, 0);
4430 		pr_debug("ConfigFS ITT[0x%08x] - t_transport_stop =="
4431 			" TRUE, skipping\n", cmd->se_tfo->get_task_tag(cmd));
4432 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4433 		transport_cmd_check_stop(cmd, 1, 0);
4434 		return -EPERM;
4435 	}
4436 	atomic_set(&cmd->transport_lun_fe_stop, 1);
4437 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4438 
4439 	wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
4440 
4441 	ret = transport_stop_tasks_for_cmd(cmd);
4442 
4443 	pr_debug("ConfigFS: cmd: %p t_tasks: %d stop tasks ret:"
4444 			" %d\n", cmd, cmd->t_task_list_num, ret);
4445 	if (!ret) {
4446 		pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
4447 				cmd->se_tfo->get_task_tag(cmd));
4448 		wait_for_completion(&cmd->transport_lun_stop_comp);
4449 		pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
4450 				cmd->se_tfo->get_task_tag(cmd));
4451 	}
4452 	transport_remove_cmd_from_queue(cmd, &cmd->se_dev->dev_queue_obj);
4453 
4454 	return 0;
4455 }
4456 
4457 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
4458 {
4459 	struct se_cmd *cmd = NULL;
4460 	unsigned long lun_flags, cmd_flags;
4461 	/*
4462 	 * Do exception processing and return CHECK_CONDITION status to the
4463 	 * Initiator Port.
4464 	 */
4465 	spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4466 	while (!list_empty(&lun->lun_cmd_list)) {
4467 		cmd = list_first_entry(&lun->lun_cmd_list,
4468 		       struct se_cmd, se_lun_node);
4469 		list_del(&cmd->se_lun_node);
4470 
4471 		atomic_set(&cmd->transport_lun_active, 0);
4472 		/*
4473 		 * This will notify iscsi_target_transport.c:
4474 		 * transport_cmd_check_stop() that a LUN shutdown is in
4475 		 * progress for the iscsi_cmd_t.
4476 		 */
4477 		spin_lock(&cmd->t_state_lock);
4478 		pr_debug("SE_LUN[%d] - Setting cmd->transport"
4479 			"_lun_stop for  ITT: 0x%08x\n",
4480 			cmd->se_lun->unpacked_lun,
4481 			cmd->se_tfo->get_task_tag(cmd));
4482 		atomic_set(&cmd->transport_lun_stop, 1);
4483 		spin_unlock(&cmd->t_state_lock);
4484 
4485 		spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
4486 
4487 		if (!cmd->se_lun) {
4488 			pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
4489 				cmd->se_tfo->get_task_tag(cmd),
4490 				cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
4491 			BUG();
4492 		}
4493 		/*
4494 		 * If the Storage engine still owns the iscsi_cmd_t, determine
4495 		 * and/or stop its context.
4496 		 */
4497 		pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
4498 			"_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
4499 			cmd->se_tfo->get_task_tag(cmd));
4500 
4501 		if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
4502 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4503 			continue;
4504 		}
4505 
4506 		pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
4507 			"_wait_for_tasks(): SUCCESS\n",
4508 			cmd->se_lun->unpacked_lun,
4509 			cmd->se_tfo->get_task_tag(cmd));
4510 
4511 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
4512 		if (!atomic_read(&cmd->transport_dev_active)) {
4513 			spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4514 			goto check_cond;
4515 		}
4516 		atomic_set(&cmd->transport_dev_active, 0);
4517 		transport_all_task_dev_remove_state(cmd);
4518 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4519 
4520 		transport_free_dev_tasks(cmd);
4521 		/*
4522 		 * The Storage engine stopped this struct se_cmd before it was
4523 		 * send to the fabric frontend for delivery back to the
4524 		 * Initiator Node.  Return this SCSI CDB back with an
4525 		 * CHECK_CONDITION status.
4526 		 */
4527 check_cond:
4528 		transport_send_check_condition_and_sense(cmd,
4529 				TCM_NON_EXISTENT_LUN, 0);
4530 		/*
4531 		 *  If the fabric frontend is waiting for this iscsi_cmd_t to
4532 		 * be released, notify the waiting thread now that LU has
4533 		 * finished accessing it.
4534 		 */
4535 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
4536 		if (atomic_read(&cmd->transport_lun_fe_stop)) {
4537 			pr_debug("SE_LUN[%d] - Detected FE stop for"
4538 				" struct se_cmd: %p ITT: 0x%08x\n",
4539 				lun->unpacked_lun,
4540 				cmd, cmd->se_tfo->get_task_tag(cmd));
4541 
4542 			spin_unlock_irqrestore(&cmd->t_state_lock,
4543 					cmd_flags);
4544 			transport_cmd_check_stop(cmd, 1, 0);
4545 			complete(&cmd->transport_lun_fe_stop_comp);
4546 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4547 			continue;
4548 		}
4549 		pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
4550 			lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
4551 
4552 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4553 		spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4554 	}
4555 	spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
4556 }
4557 
4558 static int transport_clear_lun_thread(void *p)
4559 {
4560 	struct se_lun *lun = (struct se_lun *)p;
4561 
4562 	__transport_clear_lun_from_sessions(lun);
4563 	complete(&lun->lun_shutdown_comp);
4564 
4565 	return 0;
4566 }
4567 
4568 int transport_clear_lun_from_sessions(struct se_lun *lun)
4569 {
4570 	struct task_struct *kt;
4571 
4572 	kt = kthread_run(transport_clear_lun_thread, lun,
4573 			"tcm_cl_%u", lun->unpacked_lun);
4574 	if (IS_ERR(kt)) {
4575 		pr_err("Unable to start clear_lun thread\n");
4576 		return PTR_ERR(kt);
4577 	}
4578 	wait_for_completion(&lun->lun_shutdown_comp);
4579 
4580 	return 0;
4581 }
4582 
4583 /*	transport_generic_wait_for_tasks():
4584  *
4585  *	Called from frontend or passthrough context to wait for storage engine
4586  *	to pause and/or release frontend generated struct se_cmd.
4587  */
4588 static void transport_generic_wait_for_tasks(
4589 	struct se_cmd *cmd,
4590 	int remove_cmd,
4591 	int session_reinstatement)
4592 {
4593 	unsigned long flags;
4594 
4595 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) && !(cmd->se_tmr_req))
4596 		return;
4597 
4598 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4599 	/*
4600 	 * If we are already stopped due to an external event (ie: LUN shutdown)
4601 	 * sleep until the connection can have the passed struct se_cmd back.
4602 	 * The cmd->transport_lun_stopped_sem will be upped by
4603 	 * transport_clear_lun_from_sessions() once the ConfigFS context caller
4604 	 * has completed its operation on the struct se_cmd.
4605 	 */
4606 	if (atomic_read(&cmd->transport_lun_stop)) {
4607 
4608 		pr_debug("wait_for_tasks: Stopping"
4609 			" wait_for_completion(&cmd->t_tasktransport_lun_fe"
4610 			"_stop_comp); for ITT: 0x%08x\n",
4611 			cmd->se_tfo->get_task_tag(cmd));
4612 		/*
4613 		 * There is a special case for WRITES where a FE exception +
4614 		 * LUN shutdown means ConfigFS context is still sleeping on
4615 		 * transport_lun_stop_comp in transport_lun_wait_for_tasks().
4616 		 * We go ahead and up transport_lun_stop_comp just to be sure
4617 		 * here.
4618 		 */
4619 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4620 		complete(&cmd->transport_lun_stop_comp);
4621 		wait_for_completion(&cmd->transport_lun_fe_stop_comp);
4622 		spin_lock_irqsave(&cmd->t_state_lock, flags);
4623 
4624 		transport_all_task_dev_remove_state(cmd);
4625 		/*
4626 		 * At this point, the frontend who was the originator of this
4627 		 * struct se_cmd, now owns the structure and can be released through
4628 		 * normal means below.
4629 		 */
4630 		pr_debug("wait_for_tasks: Stopped"
4631 			" wait_for_completion(&cmd->t_tasktransport_lun_fe_"
4632 			"stop_comp); for ITT: 0x%08x\n",
4633 			cmd->se_tfo->get_task_tag(cmd));
4634 
4635 		atomic_set(&cmd->transport_lun_stop, 0);
4636 	}
4637 	if (!atomic_read(&cmd->t_transport_active) ||
4638 	     atomic_read(&cmd->t_transport_aborted))
4639 		goto remove;
4640 
4641 	atomic_set(&cmd->t_transport_stop, 1);
4642 
4643 	pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
4644 		" i_state: %d, t_state/def_t_state: %d/%d, t_transport_stop"
4645 		" = TRUE\n", cmd, cmd->se_tfo->get_task_tag(cmd),
4646 		cmd->se_tfo->get_cmd_state(cmd), cmd->t_state,
4647 		cmd->deferred_t_state);
4648 
4649 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4650 
4651 	wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
4652 
4653 	wait_for_completion(&cmd->t_transport_stop_comp);
4654 
4655 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4656 	atomic_set(&cmd->t_transport_active, 0);
4657 	atomic_set(&cmd->t_transport_stop, 0);
4658 
4659 	pr_debug("wait_for_tasks: Stopped wait_for_compltion("
4660 		"&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
4661 		cmd->se_tfo->get_task_tag(cmd));
4662 remove:
4663 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4664 	if (!remove_cmd)
4665 		return;
4666 
4667 	transport_generic_free_cmd(cmd, 0, session_reinstatement);
4668 }
4669 
4670 static int transport_get_sense_codes(
4671 	struct se_cmd *cmd,
4672 	u8 *asc,
4673 	u8 *ascq)
4674 {
4675 	*asc = cmd->scsi_asc;
4676 	*ascq = cmd->scsi_ascq;
4677 
4678 	return 0;
4679 }
4680 
4681 static int transport_set_sense_codes(
4682 	struct se_cmd *cmd,
4683 	u8 asc,
4684 	u8 ascq)
4685 {
4686 	cmd->scsi_asc = asc;
4687 	cmd->scsi_ascq = ascq;
4688 
4689 	return 0;
4690 }
4691 
4692 int transport_send_check_condition_and_sense(
4693 	struct se_cmd *cmd,
4694 	u8 reason,
4695 	int from_transport)
4696 {
4697 	unsigned char *buffer = cmd->sense_buffer;
4698 	unsigned long flags;
4699 	int offset;
4700 	u8 asc = 0, ascq = 0;
4701 
4702 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4703 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
4704 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4705 		return 0;
4706 	}
4707 	cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
4708 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4709 
4710 	if (!reason && from_transport)
4711 		goto after_reason;
4712 
4713 	if (!from_transport)
4714 		cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
4715 	/*
4716 	 * Data Segment and SenseLength of the fabric response PDU.
4717 	 *
4718 	 * TRANSPORT_SENSE_BUFFER is now set to SCSI_SENSE_BUFFERSIZE
4719 	 * from include/scsi/scsi_cmnd.h
4720 	 */
4721 	offset = cmd->se_tfo->set_fabric_sense_len(cmd,
4722 				TRANSPORT_SENSE_BUFFER);
4723 	/*
4724 	 * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
4725 	 * SENSE KEY values from include/scsi/scsi.h
4726 	 */
4727 	switch (reason) {
4728 	case TCM_NON_EXISTENT_LUN:
4729 	case TCM_UNSUPPORTED_SCSI_OPCODE:
4730 	case TCM_SECTOR_COUNT_TOO_MANY:
4731 		/* CURRENT ERROR */
4732 		buffer[offset] = 0x70;
4733 		/* ILLEGAL REQUEST */
4734 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4735 		/* INVALID COMMAND OPERATION CODE */
4736 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x20;
4737 		break;
4738 	case TCM_UNKNOWN_MODE_PAGE:
4739 		/* CURRENT ERROR */
4740 		buffer[offset] = 0x70;
4741 		/* ILLEGAL REQUEST */
4742 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4743 		/* INVALID FIELD IN CDB */
4744 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
4745 		break;
4746 	case TCM_CHECK_CONDITION_ABORT_CMD:
4747 		/* CURRENT ERROR */
4748 		buffer[offset] = 0x70;
4749 		/* ABORTED COMMAND */
4750 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4751 		/* BUS DEVICE RESET FUNCTION OCCURRED */
4752 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x29;
4753 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x03;
4754 		break;
4755 	case TCM_INCORRECT_AMOUNT_OF_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 		/* NOT ENOUGH UNSOLICITED DATA */
4763 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0d;
4764 		break;
4765 	case TCM_INVALID_CDB_FIELD:
4766 		/* CURRENT ERROR */
4767 		buffer[offset] = 0x70;
4768 		/* ABORTED COMMAND */
4769 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4770 		/* INVALID FIELD IN CDB */
4771 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
4772 		break;
4773 	case TCM_INVALID_PARAMETER_LIST:
4774 		/* CURRENT ERROR */
4775 		buffer[offset] = 0x70;
4776 		/* ABORTED COMMAND */
4777 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4778 		/* INVALID FIELD IN PARAMETER LIST */
4779 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x26;
4780 		break;
4781 	case TCM_UNEXPECTED_UNSOLICITED_DATA:
4782 		/* CURRENT ERROR */
4783 		buffer[offset] = 0x70;
4784 		/* ABORTED COMMAND */
4785 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4786 		/* WRITE ERROR */
4787 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x0c;
4788 		/* UNEXPECTED_UNSOLICITED_DATA */
4789 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0c;
4790 		break;
4791 	case TCM_SERVICE_CRC_ERROR:
4792 		/* CURRENT ERROR */
4793 		buffer[offset] = 0x70;
4794 		/* ABORTED COMMAND */
4795 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4796 		/* PROTOCOL SERVICE CRC ERROR */
4797 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x47;
4798 		/* N/A */
4799 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x05;
4800 		break;
4801 	case TCM_SNACK_REJECTED:
4802 		/* CURRENT ERROR */
4803 		buffer[offset] = 0x70;
4804 		/* ABORTED COMMAND */
4805 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4806 		/* READ ERROR */
4807 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x11;
4808 		/* FAILED RETRANSMISSION REQUEST */
4809 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x13;
4810 		break;
4811 	case TCM_WRITE_PROTECTED:
4812 		/* CURRENT ERROR */
4813 		buffer[offset] = 0x70;
4814 		/* DATA PROTECT */
4815 		buffer[offset+SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
4816 		/* WRITE PROTECTED */
4817 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x27;
4818 		break;
4819 	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
4820 		/* CURRENT ERROR */
4821 		buffer[offset] = 0x70;
4822 		/* UNIT ATTENTION */
4823 		buffer[offset+SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
4824 		core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
4825 		buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
4826 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
4827 		break;
4828 	case TCM_CHECK_CONDITION_NOT_READY:
4829 		/* CURRENT ERROR */
4830 		buffer[offset] = 0x70;
4831 		/* Not Ready */
4832 		buffer[offset+SPC_SENSE_KEY_OFFSET] = NOT_READY;
4833 		transport_get_sense_codes(cmd, &asc, &ascq);
4834 		buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
4835 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
4836 		break;
4837 	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
4838 	default:
4839 		/* CURRENT ERROR */
4840 		buffer[offset] = 0x70;
4841 		/* ILLEGAL REQUEST */
4842 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4843 		/* LOGICAL UNIT COMMUNICATION FAILURE */
4844 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x80;
4845 		break;
4846 	}
4847 	/*
4848 	 * This code uses linux/include/scsi/scsi.h SAM status codes!
4849 	 */
4850 	cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
4851 	/*
4852 	 * Automatically padded, this value is encoded in the fabric's
4853 	 * data_length response PDU containing the SCSI defined sense data.
4854 	 */
4855 	cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER + offset;
4856 
4857 after_reason:
4858 	return cmd->se_tfo->queue_status(cmd);
4859 }
4860 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
4861 
4862 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
4863 {
4864 	int ret = 0;
4865 
4866 	if (atomic_read(&cmd->t_transport_aborted) != 0) {
4867 		if (!send_status ||
4868 		     (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
4869 			return 1;
4870 #if 0
4871 		pr_debug("Sending delayed SAM_STAT_TASK_ABORTED"
4872 			" status for CDB: 0x%02x ITT: 0x%08x\n",
4873 			cmd->t_task_cdb[0],
4874 			cmd->se_tfo->get_task_tag(cmd));
4875 #endif
4876 		cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
4877 		cmd->se_tfo->queue_status(cmd);
4878 		ret = 1;
4879 	}
4880 	return ret;
4881 }
4882 EXPORT_SYMBOL(transport_check_aborted_status);
4883 
4884 void transport_send_task_abort(struct se_cmd *cmd)
4885 {
4886 	/*
4887 	 * If there are still expected incoming fabric WRITEs, we wait
4888 	 * until until they have completed before sending a TASK_ABORTED
4889 	 * response.  This response with TASK_ABORTED status will be
4890 	 * queued back to fabric module by transport_check_aborted_status().
4891 	 */
4892 	if (cmd->data_direction == DMA_TO_DEVICE) {
4893 		if (cmd->se_tfo->write_pending_status(cmd) != 0) {
4894 			atomic_inc(&cmd->t_transport_aborted);
4895 			smp_mb__after_atomic_inc();
4896 			cmd->scsi_status = SAM_STAT_TASK_ABORTED;
4897 			transport_new_cmd_failure(cmd);
4898 			return;
4899 		}
4900 	}
4901 	cmd->scsi_status = SAM_STAT_TASK_ABORTED;
4902 #if 0
4903 	pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
4904 		" ITT: 0x%08x\n", cmd->t_task_cdb[0],
4905 		cmd->se_tfo->get_task_tag(cmd));
4906 #endif
4907 	cmd->se_tfo->queue_status(cmd);
4908 }
4909 
4910 /*	transport_generic_do_tmr():
4911  *
4912  *
4913  */
4914 int transport_generic_do_tmr(struct se_cmd *cmd)
4915 {
4916 	struct se_device *dev = cmd->se_dev;
4917 	struct se_tmr_req *tmr = cmd->se_tmr_req;
4918 	int ret;
4919 
4920 	switch (tmr->function) {
4921 	case TMR_ABORT_TASK:
4922 		tmr->response = TMR_FUNCTION_REJECTED;
4923 		break;
4924 	case TMR_ABORT_TASK_SET:
4925 	case TMR_CLEAR_ACA:
4926 	case TMR_CLEAR_TASK_SET:
4927 		tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
4928 		break;
4929 	case TMR_LUN_RESET:
4930 		ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
4931 		tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
4932 					 TMR_FUNCTION_REJECTED;
4933 		break;
4934 	case TMR_TARGET_WARM_RESET:
4935 		tmr->response = TMR_FUNCTION_REJECTED;
4936 		break;
4937 	case TMR_TARGET_COLD_RESET:
4938 		tmr->response = TMR_FUNCTION_REJECTED;
4939 		break;
4940 	default:
4941 		pr_err("Uknown TMR function: 0x%02x.\n",
4942 				tmr->function);
4943 		tmr->response = TMR_FUNCTION_REJECTED;
4944 		break;
4945 	}
4946 
4947 	cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
4948 	cmd->se_tfo->queue_tm_rsp(cmd);
4949 
4950 	transport_cmd_check_stop(cmd, 2, 0);
4951 	return 0;
4952 }
4953 
4954 /*
4955  *	Called with spin_lock_irq(&dev->execute_task_lock); held
4956  *
4957  */
4958 static struct se_task *
4959 transport_get_task_from_state_list(struct se_device *dev)
4960 {
4961 	struct se_task *task;
4962 
4963 	if (list_empty(&dev->state_task_list))
4964 		return NULL;
4965 
4966 	list_for_each_entry(task, &dev->state_task_list, t_state_list)
4967 		break;
4968 
4969 	list_del(&task->t_state_list);
4970 	atomic_set(&task->task_state_active, 0);
4971 
4972 	return task;
4973 }
4974 
4975 static void transport_processing_shutdown(struct se_device *dev)
4976 {
4977 	struct se_cmd *cmd;
4978 	struct se_task *task;
4979 	unsigned long flags;
4980 	/*
4981 	 * Empty the struct se_device's struct se_task state list.
4982 	 */
4983 	spin_lock_irqsave(&dev->execute_task_lock, flags);
4984 	while ((task = transport_get_task_from_state_list(dev))) {
4985 		if (!task->task_se_cmd) {
4986 			pr_err("task->task_se_cmd is NULL!\n");
4987 			continue;
4988 		}
4989 		cmd = task->task_se_cmd;
4990 
4991 		spin_unlock_irqrestore(&dev->execute_task_lock, flags);
4992 
4993 		spin_lock_irqsave(&cmd->t_state_lock, flags);
4994 
4995 		pr_debug("PT: cmd: %p task: %p ITT: 0x%08x,"
4996 			" i_state: %d, t_state/def_t_state:"
4997 			" %d/%d cdb: 0x%02x\n", cmd, task,
4998 			cmd->se_tfo->get_task_tag(cmd),
4999 			cmd->se_tfo->get_cmd_state(cmd),
5000 			cmd->t_state, cmd->deferred_t_state,
5001 			cmd->t_task_cdb[0]);
5002 		pr_debug("PT: ITT[0x%08x] - t_tasks: %d t_task_cdbs_left:"
5003 			" %d t_task_cdbs_sent: %d -- t_transport_active: %d"
5004 			" t_transport_stop: %d t_transport_sent: %d\n",
5005 			cmd->se_tfo->get_task_tag(cmd),
5006 			cmd->t_task_list_num,
5007 			atomic_read(&cmd->t_task_cdbs_left),
5008 			atomic_read(&cmd->t_task_cdbs_sent),
5009 			atomic_read(&cmd->t_transport_active),
5010 			atomic_read(&cmd->t_transport_stop),
5011 			atomic_read(&cmd->t_transport_sent));
5012 
5013 		if (atomic_read(&task->task_active)) {
5014 			atomic_set(&task->task_stop, 1);
5015 			spin_unlock_irqrestore(
5016 				&cmd->t_state_lock, flags);
5017 
5018 			pr_debug("Waiting for task: %p to shutdown for dev:"
5019 				" %p\n", task, dev);
5020 			wait_for_completion(&task->task_stop_comp);
5021 			pr_debug("Completed task: %p shutdown for dev: %p\n",
5022 				task, dev);
5023 
5024 			spin_lock_irqsave(&cmd->t_state_lock, flags);
5025 			atomic_dec(&cmd->t_task_cdbs_left);
5026 
5027 			atomic_set(&task->task_active, 0);
5028 			atomic_set(&task->task_stop, 0);
5029 		} else {
5030 			if (atomic_read(&task->task_execute_queue) != 0)
5031 				transport_remove_task_from_execute_queue(task, dev);
5032 		}
5033 		__transport_stop_task_timer(task, &flags);
5034 
5035 		if (!atomic_dec_and_test(&cmd->t_task_cdbs_ex_left)) {
5036 			spin_unlock_irqrestore(
5037 					&cmd->t_state_lock, flags);
5038 
5039 			pr_debug("Skipping task: %p, dev: %p for"
5040 				" t_task_cdbs_ex_left: %d\n", task, dev,
5041 				atomic_read(&cmd->t_task_cdbs_ex_left));
5042 
5043 			spin_lock_irqsave(&dev->execute_task_lock, flags);
5044 			continue;
5045 		}
5046 
5047 		if (atomic_read(&cmd->t_transport_active)) {
5048 			pr_debug("got t_transport_active = 1 for task: %p, dev:"
5049 					" %p\n", task, dev);
5050 
5051 			if (atomic_read(&cmd->t_fe_count)) {
5052 				spin_unlock_irqrestore(
5053 					&cmd->t_state_lock, flags);
5054 				transport_send_check_condition_and_sense(
5055 					cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE,
5056 					0);
5057 				transport_remove_cmd_from_queue(cmd,
5058 					&cmd->se_dev->dev_queue_obj);
5059 
5060 				transport_lun_remove_cmd(cmd);
5061 				transport_cmd_check_stop(cmd, 1, 0);
5062 			} else {
5063 				spin_unlock_irqrestore(
5064 					&cmd->t_state_lock, flags);
5065 
5066 				transport_remove_cmd_from_queue(cmd,
5067 					&cmd->se_dev->dev_queue_obj);
5068 
5069 				transport_lun_remove_cmd(cmd);
5070 
5071 				if (transport_cmd_check_stop(cmd, 1, 0))
5072 					transport_generic_remove(cmd, 0);
5073 			}
5074 
5075 			spin_lock_irqsave(&dev->execute_task_lock, flags);
5076 			continue;
5077 		}
5078 		pr_debug("Got t_transport_active = 0 for task: %p, dev: %p\n",
5079 				task, dev);
5080 
5081 		if (atomic_read(&cmd->t_fe_count)) {
5082 			spin_unlock_irqrestore(
5083 				&cmd->t_state_lock, flags);
5084 			transport_send_check_condition_and_sense(cmd,
5085 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
5086 			transport_remove_cmd_from_queue(cmd,
5087 				&cmd->se_dev->dev_queue_obj);
5088 
5089 			transport_lun_remove_cmd(cmd);
5090 			transport_cmd_check_stop(cmd, 1, 0);
5091 		} else {
5092 			spin_unlock_irqrestore(
5093 				&cmd->t_state_lock, flags);
5094 
5095 			transport_remove_cmd_from_queue(cmd,
5096 				&cmd->se_dev->dev_queue_obj);
5097 			transport_lun_remove_cmd(cmd);
5098 
5099 			if (transport_cmd_check_stop(cmd, 1, 0))
5100 				transport_generic_remove(cmd, 0);
5101 		}
5102 
5103 		spin_lock_irqsave(&dev->execute_task_lock, flags);
5104 	}
5105 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
5106 	/*
5107 	 * Empty the struct se_device's struct se_cmd list.
5108 	 */
5109 	while ((cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj))) {
5110 
5111 		pr_debug("From Device Queue: cmd: %p t_state: %d\n",
5112 				cmd, cmd->t_state);
5113 
5114 		if (atomic_read(&cmd->t_fe_count)) {
5115 			transport_send_check_condition_and_sense(cmd,
5116 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
5117 
5118 			transport_lun_remove_cmd(cmd);
5119 			transport_cmd_check_stop(cmd, 1, 0);
5120 		} else {
5121 			transport_lun_remove_cmd(cmd);
5122 			if (transport_cmd_check_stop(cmd, 1, 0))
5123 				transport_generic_remove(cmd, 0);
5124 		}
5125 	}
5126 }
5127 
5128 /*	transport_processing_thread():
5129  *
5130  *
5131  */
5132 static int transport_processing_thread(void *param)
5133 {
5134 	int ret;
5135 	struct se_cmd *cmd;
5136 	struct se_device *dev = (struct se_device *) param;
5137 
5138 	set_user_nice(current, -20);
5139 
5140 	while (!kthread_should_stop()) {
5141 		ret = wait_event_interruptible(dev->dev_queue_obj.thread_wq,
5142 				atomic_read(&dev->dev_queue_obj.queue_cnt) ||
5143 				kthread_should_stop());
5144 		if (ret < 0)
5145 			goto out;
5146 
5147 		spin_lock_irq(&dev->dev_status_lock);
5148 		if (dev->dev_status & TRANSPORT_DEVICE_SHUTDOWN) {
5149 			spin_unlock_irq(&dev->dev_status_lock);
5150 			transport_processing_shutdown(dev);
5151 			continue;
5152 		}
5153 		spin_unlock_irq(&dev->dev_status_lock);
5154 
5155 get_cmd:
5156 		__transport_execute_tasks(dev);
5157 
5158 		cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj);
5159 		if (!cmd)
5160 			continue;
5161 
5162 		switch (cmd->t_state) {
5163 		case TRANSPORT_NEW_CMD_MAP:
5164 			if (!cmd->se_tfo->new_cmd_map) {
5165 				pr_err("cmd->se_tfo->new_cmd_map is"
5166 					" NULL for TRANSPORT_NEW_CMD_MAP\n");
5167 				BUG();
5168 			}
5169 			ret = cmd->se_tfo->new_cmd_map(cmd);
5170 			if (ret < 0) {
5171 				cmd->transport_error_status = ret;
5172 				transport_generic_request_failure(cmd, NULL,
5173 						0, (cmd->data_direction !=
5174 						    DMA_TO_DEVICE));
5175 				break;
5176 			}
5177 			/* Fall through */
5178 		case TRANSPORT_NEW_CMD:
5179 			ret = transport_generic_new_cmd(cmd);
5180 			if (ret == -EAGAIN)
5181 				break;
5182 			else if (ret < 0) {
5183 				cmd->transport_error_status = ret;
5184 				transport_generic_request_failure(cmd, NULL,
5185 					0, (cmd->data_direction !=
5186 					 DMA_TO_DEVICE));
5187 			}
5188 			break;
5189 		case TRANSPORT_PROCESS_WRITE:
5190 			transport_generic_process_write(cmd);
5191 			break;
5192 		case TRANSPORT_COMPLETE_OK:
5193 			transport_stop_all_task_timers(cmd);
5194 			transport_generic_complete_ok(cmd);
5195 			break;
5196 		case TRANSPORT_REMOVE:
5197 			transport_generic_remove(cmd, 0);
5198 			break;
5199 		case TRANSPORT_FREE_CMD_INTR:
5200 			transport_generic_free_cmd(cmd, 0, 0);
5201 			break;
5202 		case TRANSPORT_PROCESS_TMR:
5203 			transport_generic_do_tmr(cmd);
5204 			break;
5205 		case TRANSPORT_COMPLETE_FAILURE:
5206 			transport_generic_request_failure(cmd, NULL, 1, 1);
5207 			break;
5208 		case TRANSPORT_COMPLETE_TIMEOUT:
5209 			transport_stop_all_task_timers(cmd);
5210 			transport_generic_request_timeout(cmd);
5211 			break;
5212 		case TRANSPORT_COMPLETE_QF_WP:
5213 			transport_generic_write_pending(cmd);
5214 			break;
5215 		default:
5216 			pr_err("Unknown t_state: %d deferred_t_state:"
5217 				" %d for ITT: 0x%08x i_state: %d on SE LUN:"
5218 				" %u\n", cmd->t_state, cmd->deferred_t_state,
5219 				cmd->se_tfo->get_task_tag(cmd),
5220 				cmd->se_tfo->get_cmd_state(cmd),
5221 				cmd->se_lun->unpacked_lun);
5222 			BUG();
5223 		}
5224 
5225 		goto get_cmd;
5226 	}
5227 
5228 out:
5229 	transport_release_all_cmds(dev);
5230 	dev->process_thread = NULL;
5231 	return 0;
5232 }
5233