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/net.h>
30 #include <linux/delay.h>
31 #include <linux/string.h>
32 #include <linux/timer.h>
33 #include <linux/slab.h>
34 #include <linux/blkdev.h>
35 #include <linux/spinlock.h>
36 #include <linux/kthread.h>
37 #include <linux/in.h>
38 #include <linux/cdrom.h>
39 #include <linux/module.h>
40 #include <linux/ratelimit.h>
41 #include <asm/unaligned.h>
42 #include <net/sock.h>
43 #include <net/tcp.h>
44 #include <scsi/scsi.h>
45 #include <scsi/scsi_cmnd.h>
46 #include <scsi/scsi_tcq.h>
47 
48 #include <target/target_core_base.h>
49 #include <target/target_core_backend.h>
50 #include <target/target_core_fabric.h>
51 #include <target/target_core_configfs.h>
52 
53 #include "target_core_internal.h"
54 #include "target_core_alua.h"
55 #include "target_core_pr.h"
56 #include "target_core_ua.h"
57 
58 static int sub_api_initialized;
59 
60 static struct workqueue_struct *target_completion_wq;
61 static struct kmem_cache *se_sess_cache;
62 struct kmem_cache *se_ua_cache;
63 struct kmem_cache *t10_pr_reg_cache;
64 struct kmem_cache *t10_alua_lu_gp_cache;
65 struct kmem_cache *t10_alua_lu_gp_mem_cache;
66 struct kmem_cache *t10_alua_tg_pt_gp_cache;
67 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
68 
69 static int transport_generic_write_pending(struct se_cmd *);
70 static int transport_processing_thread(void *param);
71 static int __transport_execute_tasks(struct se_device *dev, struct se_cmd *);
72 static void transport_complete_task_attr(struct se_cmd *cmd);
73 static void transport_handle_queue_full(struct se_cmd *cmd,
74 		struct se_device *dev);
75 static void transport_free_dev_tasks(struct se_cmd *cmd);
76 static int transport_generic_get_mem(struct se_cmd *cmd);
77 static void transport_put_cmd(struct se_cmd *cmd);
78 static void transport_remove_cmd_from_queue(struct se_cmd *cmd);
79 static int transport_set_sense_codes(struct se_cmd *cmd, u8 asc, u8 ascq);
80 static void target_complete_ok_work(struct work_struct *work);
81 
82 int init_se_kmem_caches(void)
83 {
84 	se_sess_cache = kmem_cache_create("se_sess_cache",
85 			sizeof(struct se_session), __alignof__(struct se_session),
86 			0, NULL);
87 	if (!se_sess_cache) {
88 		pr_err("kmem_cache_create() for struct se_session"
89 				" failed\n");
90 		goto out;
91 	}
92 	se_ua_cache = kmem_cache_create("se_ua_cache",
93 			sizeof(struct se_ua), __alignof__(struct se_ua),
94 			0, NULL);
95 	if (!se_ua_cache) {
96 		pr_err("kmem_cache_create() for struct se_ua failed\n");
97 		goto out_free_sess_cache;
98 	}
99 	t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
100 			sizeof(struct t10_pr_registration),
101 			__alignof__(struct t10_pr_registration), 0, NULL);
102 	if (!t10_pr_reg_cache) {
103 		pr_err("kmem_cache_create() for struct t10_pr_registration"
104 				" failed\n");
105 		goto out_free_ua_cache;
106 	}
107 	t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
108 			sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
109 			0, NULL);
110 	if (!t10_alua_lu_gp_cache) {
111 		pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
112 				" failed\n");
113 		goto out_free_pr_reg_cache;
114 	}
115 	t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
116 			sizeof(struct t10_alua_lu_gp_member),
117 			__alignof__(struct t10_alua_lu_gp_member), 0, NULL);
118 	if (!t10_alua_lu_gp_mem_cache) {
119 		pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
120 				"cache failed\n");
121 		goto out_free_lu_gp_cache;
122 	}
123 	t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
124 			sizeof(struct t10_alua_tg_pt_gp),
125 			__alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
126 	if (!t10_alua_tg_pt_gp_cache) {
127 		pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
128 				"cache failed\n");
129 		goto out_free_lu_gp_mem_cache;
130 	}
131 	t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
132 			"t10_alua_tg_pt_gp_mem_cache",
133 			sizeof(struct t10_alua_tg_pt_gp_member),
134 			__alignof__(struct t10_alua_tg_pt_gp_member),
135 			0, NULL);
136 	if (!t10_alua_tg_pt_gp_mem_cache) {
137 		pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
138 				"mem_t failed\n");
139 		goto out_free_tg_pt_gp_cache;
140 	}
141 
142 	target_completion_wq = alloc_workqueue("target_completion",
143 					       WQ_MEM_RECLAIM, 0);
144 	if (!target_completion_wq)
145 		goto out_free_tg_pt_gp_mem_cache;
146 
147 	return 0;
148 
149 out_free_tg_pt_gp_mem_cache:
150 	kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
151 out_free_tg_pt_gp_cache:
152 	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
153 out_free_lu_gp_mem_cache:
154 	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
155 out_free_lu_gp_cache:
156 	kmem_cache_destroy(t10_alua_lu_gp_cache);
157 out_free_pr_reg_cache:
158 	kmem_cache_destroy(t10_pr_reg_cache);
159 out_free_ua_cache:
160 	kmem_cache_destroy(se_ua_cache);
161 out_free_sess_cache:
162 	kmem_cache_destroy(se_sess_cache);
163 out:
164 	return -ENOMEM;
165 }
166 
167 void release_se_kmem_caches(void)
168 {
169 	destroy_workqueue(target_completion_wq);
170 	kmem_cache_destroy(se_sess_cache);
171 	kmem_cache_destroy(se_ua_cache);
172 	kmem_cache_destroy(t10_pr_reg_cache);
173 	kmem_cache_destroy(t10_alua_lu_gp_cache);
174 	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
175 	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
176 	kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
177 }
178 
179 /* This code ensures unique mib indexes are handed out. */
180 static DEFINE_SPINLOCK(scsi_mib_index_lock);
181 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
182 
183 /*
184  * Allocate a new row index for the entry type specified
185  */
186 u32 scsi_get_new_index(scsi_index_t type)
187 {
188 	u32 new_index;
189 
190 	BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
191 
192 	spin_lock(&scsi_mib_index_lock);
193 	new_index = ++scsi_mib_index[type];
194 	spin_unlock(&scsi_mib_index_lock);
195 
196 	return new_index;
197 }
198 
199 static void transport_init_queue_obj(struct se_queue_obj *qobj)
200 {
201 	atomic_set(&qobj->queue_cnt, 0);
202 	INIT_LIST_HEAD(&qobj->qobj_list);
203 	init_waitqueue_head(&qobj->thread_wq);
204 	spin_lock_init(&qobj->cmd_queue_lock);
205 }
206 
207 void transport_subsystem_check_init(void)
208 {
209 	int ret;
210 
211 	if (sub_api_initialized)
212 		return;
213 
214 	ret = request_module("target_core_iblock");
215 	if (ret != 0)
216 		pr_err("Unable to load target_core_iblock\n");
217 
218 	ret = request_module("target_core_file");
219 	if (ret != 0)
220 		pr_err("Unable to load target_core_file\n");
221 
222 	ret = request_module("target_core_pscsi");
223 	if (ret != 0)
224 		pr_err("Unable to load target_core_pscsi\n");
225 
226 	ret = request_module("target_core_stgt");
227 	if (ret != 0)
228 		pr_err("Unable to load target_core_stgt\n");
229 
230 	sub_api_initialized = 1;
231 	return;
232 }
233 
234 struct se_session *transport_init_session(void)
235 {
236 	struct se_session *se_sess;
237 
238 	se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
239 	if (!se_sess) {
240 		pr_err("Unable to allocate struct se_session from"
241 				" se_sess_cache\n");
242 		return ERR_PTR(-ENOMEM);
243 	}
244 	INIT_LIST_HEAD(&se_sess->sess_list);
245 	INIT_LIST_HEAD(&se_sess->sess_acl_list);
246 	INIT_LIST_HEAD(&se_sess->sess_cmd_list);
247 	INIT_LIST_HEAD(&se_sess->sess_wait_list);
248 	spin_lock_init(&se_sess->sess_cmd_lock);
249 	kref_init(&se_sess->sess_kref);
250 
251 	return se_sess;
252 }
253 EXPORT_SYMBOL(transport_init_session);
254 
255 /*
256  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
257  */
258 void __transport_register_session(
259 	struct se_portal_group *se_tpg,
260 	struct se_node_acl *se_nacl,
261 	struct se_session *se_sess,
262 	void *fabric_sess_ptr)
263 {
264 	unsigned char buf[PR_REG_ISID_LEN];
265 
266 	se_sess->se_tpg = se_tpg;
267 	se_sess->fabric_sess_ptr = fabric_sess_ptr;
268 	/*
269 	 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
270 	 *
271 	 * Only set for struct se_session's that will actually be moving I/O.
272 	 * eg: *NOT* discovery sessions.
273 	 */
274 	if (se_nacl) {
275 		/*
276 		 * If the fabric module supports an ISID based TransportID,
277 		 * save this value in binary from the fabric I_T Nexus now.
278 		 */
279 		if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
280 			memset(&buf[0], 0, PR_REG_ISID_LEN);
281 			se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
282 					&buf[0], PR_REG_ISID_LEN);
283 			se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
284 		}
285 		kref_get(&se_nacl->acl_kref);
286 
287 		spin_lock_irq(&se_nacl->nacl_sess_lock);
288 		/*
289 		 * The se_nacl->nacl_sess pointer will be set to the
290 		 * last active I_T Nexus for each struct se_node_acl.
291 		 */
292 		se_nacl->nacl_sess = se_sess;
293 
294 		list_add_tail(&se_sess->sess_acl_list,
295 			      &se_nacl->acl_sess_list);
296 		spin_unlock_irq(&se_nacl->nacl_sess_lock);
297 	}
298 	list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
299 
300 	pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
301 		se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
302 }
303 EXPORT_SYMBOL(__transport_register_session);
304 
305 void transport_register_session(
306 	struct se_portal_group *se_tpg,
307 	struct se_node_acl *se_nacl,
308 	struct se_session *se_sess,
309 	void *fabric_sess_ptr)
310 {
311 	unsigned long flags;
312 
313 	spin_lock_irqsave(&se_tpg->session_lock, flags);
314 	__transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
315 	spin_unlock_irqrestore(&se_tpg->session_lock, flags);
316 }
317 EXPORT_SYMBOL(transport_register_session);
318 
319 static void target_release_session(struct kref *kref)
320 {
321 	struct se_session *se_sess = container_of(kref,
322 			struct se_session, sess_kref);
323 	struct se_portal_group *se_tpg = se_sess->se_tpg;
324 
325 	se_tpg->se_tpg_tfo->close_session(se_sess);
326 }
327 
328 void target_get_session(struct se_session *se_sess)
329 {
330 	kref_get(&se_sess->sess_kref);
331 }
332 EXPORT_SYMBOL(target_get_session);
333 
334 int target_put_session(struct se_session *se_sess)
335 {
336 	return kref_put(&se_sess->sess_kref, target_release_session);
337 }
338 EXPORT_SYMBOL(target_put_session);
339 
340 static void target_complete_nacl(struct kref *kref)
341 {
342 	struct se_node_acl *nacl = container_of(kref,
343 				struct se_node_acl, acl_kref);
344 
345 	complete(&nacl->acl_free_comp);
346 }
347 
348 void target_put_nacl(struct se_node_acl *nacl)
349 {
350 	kref_put(&nacl->acl_kref, target_complete_nacl);
351 }
352 
353 void transport_deregister_session_configfs(struct se_session *se_sess)
354 {
355 	struct se_node_acl *se_nacl;
356 	unsigned long flags;
357 	/*
358 	 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
359 	 */
360 	se_nacl = se_sess->se_node_acl;
361 	if (se_nacl) {
362 		spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
363 		if (se_nacl->acl_stop == 0)
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 target_core_fabric_ops *se_tfo;
392 	struct se_node_acl *se_nacl;
393 	unsigned long flags;
394 	bool comp_nacl = true;
395 
396 	if (!se_tpg) {
397 		transport_free_session(se_sess);
398 		return;
399 	}
400 	se_tfo = se_tpg->se_tpg_tfo;
401 
402 	spin_lock_irqsave(&se_tpg->session_lock, flags);
403 	list_del(&se_sess->sess_list);
404 	se_sess->se_tpg = NULL;
405 	se_sess->fabric_sess_ptr = NULL;
406 	spin_unlock_irqrestore(&se_tpg->session_lock, flags);
407 
408 	/*
409 	 * Determine if we need to do extra work for this initiator node's
410 	 * struct se_node_acl if it had been previously dynamically generated.
411 	 */
412 	se_nacl = se_sess->se_node_acl;
413 
414 	spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
415 	if (se_nacl && se_nacl->dynamic_node_acl) {
416 		if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
417 			list_del(&se_nacl->acl_list);
418 			se_tpg->num_node_acls--;
419 			spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
420 			core_tpg_wait_for_nacl_pr_ref(se_nacl);
421 			core_free_device_list_for_node(se_nacl, se_tpg);
422 			se_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
423 
424 			comp_nacl = false;
425 			spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
426 		}
427 	}
428 	spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
429 
430 	pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
431 		se_tpg->se_tpg_tfo->get_fabric_name());
432 	/*
433 	 * If last kref is dropping now for an explict NodeACL, awake sleeping
434 	 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
435 	 * removal context.
436 	 */
437 	if (se_nacl && comp_nacl == true)
438 		target_put_nacl(se_nacl);
439 
440 	transport_free_session(se_sess);
441 }
442 EXPORT_SYMBOL(transport_deregister_session);
443 
444 /*
445  * Called with cmd->t_state_lock held.
446  */
447 static void transport_all_task_dev_remove_state(struct se_cmd *cmd)
448 {
449 	struct se_device *dev = cmd->se_dev;
450 	struct se_task *task;
451 	unsigned long flags;
452 
453 	if (!dev)
454 		return;
455 
456 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
457 		if (task->task_flags & TF_ACTIVE)
458 			continue;
459 
460 		spin_lock_irqsave(&dev->execute_task_lock, flags);
461 		if (task->t_state_active) {
462 			pr_debug("Removed ITT: 0x%08x dev: %p task[%p]\n",
463 				cmd->se_tfo->get_task_tag(cmd), dev, task);
464 
465 			list_del(&task->t_state_list);
466 			atomic_dec(&cmd->t_task_cdbs_ex_left);
467 			task->t_state_active = false;
468 		}
469 		spin_unlock_irqrestore(&dev->execute_task_lock, flags);
470 	}
471 
472 }
473 
474 /*	transport_cmd_check_stop():
475  *
476  *	'transport_off = 1' determines if CMD_T_ACTIVE should be cleared.
477  *	'transport_off = 2' determines if task_dev_state should be removed.
478  *
479  *	A non-zero u8 t_state sets cmd->t_state.
480  *	Returns 1 when command is stopped, else 0.
481  */
482 static int transport_cmd_check_stop(
483 	struct se_cmd *cmd,
484 	int transport_off,
485 	u8 t_state)
486 {
487 	unsigned long flags;
488 
489 	spin_lock_irqsave(&cmd->t_state_lock, flags);
490 	/*
491 	 * Determine if IOCTL context caller in requesting the stopping of this
492 	 * command for LUN shutdown purposes.
493 	 */
494 	if (cmd->transport_state & CMD_T_LUN_STOP) {
495 		pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
496 			__func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
497 
498 		cmd->transport_state &= ~CMD_T_ACTIVE;
499 		if (transport_off == 2)
500 			transport_all_task_dev_remove_state(cmd);
501 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
502 
503 		complete(&cmd->transport_lun_stop_comp);
504 		return 1;
505 	}
506 	/*
507 	 * Determine if frontend context caller is requesting the stopping of
508 	 * this command for frontend exceptions.
509 	 */
510 	if (cmd->transport_state & CMD_T_STOP) {
511 		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
512 			__func__, __LINE__,
513 			cmd->se_tfo->get_task_tag(cmd));
514 
515 		if (transport_off == 2)
516 			transport_all_task_dev_remove_state(cmd);
517 
518 		/*
519 		 * Clear struct se_cmd->se_lun before the transport_off == 2 handoff
520 		 * to FE.
521 		 */
522 		if (transport_off == 2)
523 			cmd->se_lun = NULL;
524 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
525 
526 		complete(&cmd->t_transport_stop_comp);
527 		return 1;
528 	}
529 	if (transport_off) {
530 		cmd->transport_state &= ~CMD_T_ACTIVE;
531 		if (transport_off == 2) {
532 			transport_all_task_dev_remove_state(cmd);
533 			/*
534 			 * Clear struct se_cmd->se_lun before the transport_off == 2
535 			 * handoff to fabric module.
536 			 */
537 			cmd->se_lun = NULL;
538 			/*
539 			 * Some fabric modules like tcm_loop can release
540 			 * their internally allocated I/O reference now and
541 			 * struct se_cmd now.
542 			 *
543 			 * Fabric modules are expected to return '1' here if the
544 			 * se_cmd being passed is released at this point,
545 			 * or zero if not being released.
546 			 */
547 			if (cmd->se_tfo->check_stop_free != NULL) {
548 				spin_unlock_irqrestore(
549 					&cmd->t_state_lock, flags);
550 
551 				return cmd->se_tfo->check_stop_free(cmd);
552 			}
553 		}
554 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
555 
556 		return 0;
557 	} else if (t_state)
558 		cmd->t_state = t_state;
559 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
560 
561 	return 0;
562 }
563 
564 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
565 {
566 	return transport_cmd_check_stop(cmd, 2, 0);
567 }
568 
569 static void transport_lun_remove_cmd(struct se_cmd *cmd)
570 {
571 	struct se_lun *lun = cmd->se_lun;
572 	unsigned long flags;
573 
574 	if (!lun)
575 		return;
576 
577 	spin_lock_irqsave(&cmd->t_state_lock, flags);
578 	if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
579 		cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
580 		transport_all_task_dev_remove_state(cmd);
581 	}
582 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
583 
584 	spin_lock_irqsave(&lun->lun_cmd_lock, flags);
585 	if (!list_empty(&cmd->se_lun_node))
586 		list_del_init(&cmd->se_lun_node);
587 	spin_unlock_irqrestore(&lun->lun_cmd_lock, flags);
588 }
589 
590 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
591 {
592 	if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
593 		transport_lun_remove_cmd(cmd);
594 
595 	if (transport_cmd_check_stop_to_fabric(cmd))
596 		return;
597 	if (remove) {
598 		transport_remove_cmd_from_queue(cmd);
599 		transport_put_cmd(cmd);
600 	}
601 }
602 
603 static void transport_add_cmd_to_queue(struct se_cmd *cmd, int t_state,
604 		bool at_head)
605 {
606 	struct se_device *dev = cmd->se_dev;
607 	struct se_queue_obj *qobj = &dev->dev_queue_obj;
608 	unsigned long flags;
609 
610 	if (t_state) {
611 		spin_lock_irqsave(&cmd->t_state_lock, flags);
612 		cmd->t_state = t_state;
613 		cmd->transport_state |= CMD_T_ACTIVE;
614 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
615 	}
616 
617 	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
618 
619 	/* If the cmd is already on the list, remove it before we add it */
620 	if (!list_empty(&cmd->se_queue_node))
621 		list_del(&cmd->se_queue_node);
622 	else
623 		atomic_inc(&qobj->queue_cnt);
624 
625 	if (at_head)
626 		list_add(&cmd->se_queue_node, &qobj->qobj_list);
627 	else
628 		list_add_tail(&cmd->se_queue_node, &qobj->qobj_list);
629 	cmd->transport_state |= CMD_T_QUEUED;
630 	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
631 
632 	wake_up_interruptible(&qobj->thread_wq);
633 }
634 
635 static struct se_cmd *
636 transport_get_cmd_from_queue(struct se_queue_obj *qobj)
637 {
638 	struct se_cmd *cmd;
639 	unsigned long flags;
640 
641 	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
642 	if (list_empty(&qobj->qobj_list)) {
643 		spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
644 		return NULL;
645 	}
646 	cmd = list_first_entry(&qobj->qobj_list, struct se_cmd, se_queue_node);
647 
648 	cmd->transport_state &= ~CMD_T_QUEUED;
649 	list_del_init(&cmd->se_queue_node);
650 	atomic_dec(&qobj->queue_cnt);
651 	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
652 
653 	return cmd;
654 }
655 
656 static void transport_remove_cmd_from_queue(struct se_cmd *cmd)
657 {
658 	struct se_queue_obj *qobj = &cmd->se_dev->dev_queue_obj;
659 	unsigned long flags;
660 
661 	spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
662 	if (!(cmd->transport_state & CMD_T_QUEUED)) {
663 		spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
664 		return;
665 	}
666 	cmd->transport_state &= ~CMD_T_QUEUED;
667 	atomic_dec(&qobj->queue_cnt);
668 	list_del_init(&cmd->se_queue_node);
669 	spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
670 }
671 
672 /*
673  * Completion function used by TCM subsystem plugins (such as FILEIO)
674  * for queueing up response from struct se_subsystem_api->do_task()
675  */
676 void transport_complete_sync_cache(struct se_cmd *cmd, int good)
677 {
678 	struct se_task *task = list_entry(cmd->t_task_list.next,
679 				struct se_task, t_list);
680 
681 	if (good) {
682 		cmd->scsi_status = SAM_STAT_GOOD;
683 		task->task_scsi_status = GOOD;
684 	} else {
685 		task->task_scsi_status = SAM_STAT_CHECK_CONDITION;
686 		task->task_se_cmd->scsi_sense_reason =
687 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
688 
689 	}
690 
691 	transport_complete_task(task, good);
692 }
693 EXPORT_SYMBOL(transport_complete_sync_cache);
694 
695 static void target_complete_failure_work(struct work_struct *work)
696 {
697 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
698 
699 	transport_generic_request_failure(cmd);
700 }
701 
702 /*	transport_complete_task():
703  *
704  *	Called from interrupt and non interrupt context depending
705  *	on the transport plugin.
706  */
707 void transport_complete_task(struct se_task *task, int success)
708 {
709 	struct se_cmd *cmd = task->task_se_cmd;
710 	struct se_device *dev = cmd->se_dev;
711 	unsigned long flags;
712 
713 	spin_lock_irqsave(&cmd->t_state_lock, flags);
714 	task->task_flags &= ~TF_ACTIVE;
715 
716 	/*
717 	 * See if any sense data exists, if so set the TASK_SENSE flag.
718 	 * Also check for any other post completion work that needs to be
719 	 * done by the plugins.
720 	 */
721 	if (dev && dev->transport->transport_complete) {
722 		if (dev->transport->transport_complete(task) != 0) {
723 			cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
724 			task->task_flags |= TF_HAS_SENSE;
725 			success = 1;
726 		}
727 	}
728 
729 	/*
730 	 * See if we are waiting for outstanding struct se_task
731 	 * to complete for an exception condition
732 	 */
733 	if (task->task_flags & TF_REQUEST_STOP) {
734 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
735 		complete(&task->task_stop_comp);
736 		return;
737 	}
738 
739 	if (!success)
740 		cmd->transport_state |= CMD_T_FAILED;
741 
742 	/*
743 	 * Decrement the outstanding t_task_cdbs_left count.  The last
744 	 * struct se_task from struct se_cmd will complete itself into the
745 	 * device queue depending upon int success.
746 	 */
747 	if (!atomic_dec_and_test(&cmd->t_task_cdbs_left)) {
748 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
749 		return;
750 	}
751 	/*
752 	 * Check for case where an explict ABORT_TASK has been received
753 	 * and transport_wait_for_tasks() will be waiting for completion..
754 	 */
755 	if (cmd->transport_state & CMD_T_ABORTED &&
756 	    cmd->transport_state & CMD_T_STOP) {
757 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
758 		complete(&cmd->t_transport_stop_comp);
759 		return;
760 	} else if (cmd->transport_state & CMD_T_FAILED) {
761 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
762 		INIT_WORK(&cmd->work, target_complete_failure_work);
763 	} else {
764 		INIT_WORK(&cmd->work, target_complete_ok_work);
765 	}
766 
767 	cmd->t_state = TRANSPORT_COMPLETE;
768 	cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
769 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
770 
771 	queue_work(target_completion_wq, &cmd->work);
772 }
773 EXPORT_SYMBOL(transport_complete_task);
774 
775 /*
776  * Called by transport_add_tasks_from_cmd() once a struct se_cmd's
777  * struct se_task list are ready to be added to the active execution list
778  * struct se_device
779 
780  * Called with se_dev_t->execute_task_lock called.
781  */
782 static inline int transport_add_task_check_sam_attr(
783 	struct se_task *task,
784 	struct se_task *task_prev,
785 	struct se_device *dev)
786 {
787 	/*
788 	 * No SAM Task attribute emulation enabled, add to tail of
789 	 * execution queue
790 	 */
791 	if (dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED) {
792 		list_add_tail(&task->t_execute_list, &dev->execute_task_list);
793 		return 0;
794 	}
795 	/*
796 	 * HEAD_OF_QUEUE attribute for received CDB, which means
797 	 * the first task that is associated with a struct se_cmd goes to
798 	 * head of the struct se_device->execute_task_list, and task_prev
799 	 * after that for each subsequent task
800 	 */
801 	if (task->task_se_cmd->sam_task_attr == MSG_HEAD_TAG) {
802 		list_add(&task->t_execute_list,
803 				(task_prev != NULL) ?
804 				&task_prev->t_execute_list :
805 				&dev->execute_task_list);
806 
807 		pr_debug("Set HEAD_OF_QUEUE for task CDB: 0x%02x"
808 				" in execution queue\n",
809 				task->task_se_cmd->t_task_cdb[0]);
810 		return 1;
811 	}
812 	/*
813 	 * For ORDERED, SIMPLE or UNTAGGED attribute tasks once they have been
814 	 * transitioned from Dermant -> Active state, and are added to the end
815 	 * of the struct se_device->execute_task_list
816 	 */
817 	list_add_tail(&task->t_execute_list, &dev->execute_task_list);
818 	return 0;
819 }
820 
821 /*	__transport_add_task_to_execute_queue():
822  *
823  *	Called with se_dev_t->execute_task_lock called.
824  */
825 static void __transport_add_task_to_execute_queue(
826 	struct se_task *task,
827 	struct se_task *task_prev,
828 	struct se_device *dev)
829 {
830 	int head_of_queue;
831 
832 	head_of_queue = transport_add_task_check_sam_attr(task, task_prev, dev);
833 	atomic_inc(&dev->execute_tasks);
834 
835 	if (task->t_state_active)
836 		return;
837 	/*
838 	 * Determine if this task needs to go to HEAD_OF_QUEUE for the
839 	 * state list as well.  Running with SAM Task Attribute emulation
840 	 * will always return head_of_queue == 0 here
841 	 */
842 	if (head_of_queue)
843 		list_add(&task->t_state_list, (task_prev) ?
844 				&task_prev->t_state_list :
845 				&dev->state_task_list);
846 	else
847 		list_add_tail(&task->t_state_list, &dev->state_task_list);
848 
849 	task->t_state_active = true;
850 
851 	pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n",
852 		task->task_se_cmd->se_tfo->get_task_tag(task->task_se_cmd),
853 		task, dev);
854 }
855 
856 static void transport_add_tasks_to_state_queue(struct se_cmd *cmd)
857 {
858 	struct se_device *dev = cmd->se_dev;
859 	struct se_task *task;
860 	unsigned long flags;
861 
862 	spin_lock_irqsave(&cmd->t_state_lock, flags);
863 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
864 		spin_lock(&dev->execute_task_lock);
865 		if (!task->t_state_active) {
866 			list_add_tail(&task->t_state_list,
867 				      &dev->state_task_list);
868 			task->t_state_active = true;
869 
870 			pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n",
871 				task->task_se_cmd->se_tfo->get_task_tag(
872 				task->task_se_cmd), task, dev);
873 		}
874 		spin_unlock(&dev->execute_task_lock);
875 	}
876 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
877 }
878 
879 static void __transport_add_tasks_from_cmd(struct se_cmd *cmd)
880 {
881 	struct se_device *dev = cmd->se_dev;
882 	struct se_task *task, *task_prev = NULL;
883 
884 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
885 		if (!list_empty(&task->t_execute_list))
886 			continue;
887 		/*
888 		 * __transport_add_task_to_execute_queue() handles the
889 		 * SAM Task Attribute emulation if enabled
890 		 */
891 		__transport_add_task_to_execute_queue(task, task_prev, dev);
892 		task_prev = task;
893 	}
894 }
895 
896 static void transport_add_tasks_from_cmd(struct se_cmd *cmd)
897 {
898 	unsigned long flags;
899 	struct se_device *dev = cmd->se_dev;
900 
901 	spin_lock_irqsave(&dev->execute_task_lock, flags);
902 	__transport_add_tasks_from_cmd(cmd);
903 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
904 }
905 
906 void __transport_remove_task_from_execute_queue(struct se_task *task,
907 		struct se_device *dev)
908 {
909 	list_del_init(&task->t_execute_list);
910 	atomic_dec(&dev->execute_tasks);
911 }
912 
913 static void transport_remove_task_from_execute_queue(
914 	struct se_task *task,
915 	struct se_device *dev)
916 {
917 	unsigned long flags;
918 
919 	if (WARN_ON(list_empty(&task->t_execute_list)))
920 		return;
921 
922 	spin_lock_irqsave(&dev->execute_task_lock, flags);
923 	__transport_remove_task_from_execute_queue(task, dev);
924 	spin_unlock_irqrestore(&dev->execute_task_lock, flags);
925 }
926 
927 /*
928  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
929  */
930 
931 static void target_qf_do_work(struct work_struct *work)
932 {
933 	struct se_device *dev = container_of(work, struct se_device,
934 					qf_work_queue);
935 	LIST_HEAD(qf_cmd_list);
936 	struct se_cmd *cmd, *cmd_tmp;
937 
938 	spin_lock_irq(&dev->qf_cmd_lock);
939 	list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
940 	spin_unlock_irq(&dev->qf_cmd_lock);
941 
942 	list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
943 		list_del(&cmd->se_qf_node);
944 		atomic_dec(&dev->dev_qf_count);
945 		smp_mb__after_atomic_dec();
946 
947 		pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
948 			" context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
949 			(cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
950 			(cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
951 			: "UNKNOWN");
952 
953 		transport_add_cmd_to_queue(cmd, cmd->t_state, true);
954 	}
955 }
956 
957 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
958 {
959 	switch (cmd->data_direction) {
960 	case DMA_NONE:
961 		return "NONE";
962 	case DMA_FROM_DEVICE:
963 		return "READ";
964 	case DMA_TO_DEVICE:
965 		return "WRITE";
966 	case DMA_BIDIRECTIONAL:
967 		return "BIDI";
968 	default:
969 		break;
970 	}
971 
972 	return "UNKNOWN";
973 }
974 
975 void transport_dump_dev_state(
976 	struct se_device *dev,
977 	char *b,
978 	int *bl)
979 {
980 	*bl += sprintf(b + *bl, "Status: ");
981 	switch (dev->dev_status) {
982 	case TRANSPORT_DEVICE_ACTIVATED:
983 		*bl += sprintf(b + *bl, "ACTIVATED");
984 		break;
985 	case TRANSPORT_DEVICE_DEACTIVATED:
986 		*bl += sprintf(b + *bl, "DEACTIVATED");
987 		break;
988 	case TRANSPORT_DEVICE_SHUTDOWN:
989 		*bl += sprintf(b + *bl, "SHUTDOWN");
990 		break;
991 	case TRANSPORT_DEVICE_OFFLINE_ACTIVATED:
992 	case TRANSPORT_DEVICE_OFFLINE_DEACTIVATED:
993 		*bl += sprintf(b + *bl, "OFFLINE");
994 		break;
995 	default:
996 		*bl += sprintf(b + *bl, "UNKNOWN=%d", dev->dev_status);
997 		break;
998 	}
999 
1000 	*bl += sprintf(b + *bl, "  Execute/Max Queue Depth: %d/%d",
1001 		atomic_read(&dev->execute_tasks), dev->queue_depth);
1002 	*bl += sprintf(b + *bl, "  SectorSize: %u  MaxSectors: %u\n",
1003 		dev->se_sub_dev->se_dev_attrib.block_size, dev->se_sub_dev->se_dev_attrib.max_sectors);
1004 	*bl += sprintf(b + *bl, "        ");
1005 }
1006 
1007 void transport_dump_vpd_proto_id(
1008 	struct t10_vpd *vpd,
1009 	unsigned char *p_buf,
1010 	int p_buf_len)
1011 {
1012 	unsigned char buf[VPD_TMP_BUF_SIZE];
1013 	int len;
1014 
1015 	memset(buf, 0, VPD_TMP_BUF_SIZE);
1016 	len = sprintf(buf, "T10 VPD Protocol Identifier: ");
1017 
1018 	switch (vpd->protocol_identifier) {
1019 	case 0x00:
1020 		sprintf(buf+len, "Fibre Channel\n");
1021 		break;
1022 	case 0x10:
1023 		sprintf(buf+len, "Parallel SCSI\n");
1024 		break;
1025 	case 0x20:
1026 		sprintf(buf+len, "SSA\n");
1027 		break;
1028 	case 0x30:
1029 		sprintf(buf+len, "IEEE 1394\n");
1030 		break;
1031 	case 0x40:
1032 		sprintf(buf+len, "SCSI Remote Direct Memory Access"
1033 				" Protocol\n");
1034 		break;
1035 	case 0x50:
1036 		sprintf(buf+len, "Internet SCSI (iSCSI)\n");
1037 		break;
1038 	case 0x60:
1039 		sprintf(buf+len, "SAS Serial SCSI Protocol\n");
1040 		break;
1041 	case 0x70:
1042 		sprintf(buf+len, "Automation/Drive Interface Transport"
1043 				" Protocol\n");
1044 		break;
1045 	case 0x80:
1046 		sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
1047 		break;
1048 	default:
1049 		sprintf(buf+len, "Unknown 0x%02x\n",
1050 				vpd->protocol_identifier);
1051 		break;
1052 	}
1053 
1054 	if (p_buf)
1055 		strncpy(p_buf, buf, p_buf_len);
1056 	else
1057 		pr_debug("%s", buf);
1058 }
1059 
1060 void
1061 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1062 {
1063 	/*
1064 	 * Check if the Protocol Identifier Valid (PIV) bit is set..
1065 	 *
1066 	 * from spc3r23.pdf section 7.5.1
1067 	 */
1068 	 if (page_83[1] & 0x80) {
1069 		vpd->protocol_identifier = (page_83[0] & 0xf0);
1070 		vpd->protocol_identifier_set = 1;
1071 		transport_dump_vpd_proto_id(vpd, NULL, 0);
1072 	}
1073 }
1074 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1075 
1076 int transport_dump_vpd_assoc(
1077 	struct t10_vpd *vpd,
1078 	unsigned char *p_buf,
1079 	int p_buf_len)
1080 {
1081 	unsigned char buf[VPD_TMP_BUF_SIZE];
1082 	int ret = 0;
1083 	int len;
1084 
1085 	memset(buf, 0, VPD_TMP_BUF_SIZE);
1086 	len = sprintf(buf, "T10 VPD Identifier Association: ");
1087 
1088 	switch (vpd->association) {
1089 	case 0x00:
1090 		sprintf(buf+len, "addressed logical unit\n");
1091 		break;
1092 	case 0x10:
1093 		sprintf(buf+len, "target port\n");
1094 		break;
1095 	case 0x20:
1096 		sprintf(buf+len, "SCSI target device\n");
1097 		break;
1098 	default:
1099 		sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1100 		ret = -EINVAL;
1101 		break;
1102 	}
1103 
1104 	if (p_buf)
1105 		strncpy(p_buf, buf, p_buf_len);
1106 	else
1107 		pr_debug("%s", buf);
1108 
1109 	return ret;
1110 }
1111 
1112 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1113 {
1114 	/*
1115 	 * The VPD identification association..
1116 	 *
1117 	 * from spc3r23.pdf Section 7.6.3.1 Table 297
1118 	 */
1119 	vpd->association = (page_83[1] & 0x30);
1120 	return transport_dump_vpd_assoc(vpd, NULL, 0);
1121 }
1122 EXPORT_SYMBOL(transport_set_vpd_assoc);
1123 
1124 int transport_dump_vpd_ident_type(
1125 	struct t10_vpd *vpd,
1126 	unsigned char *p_buf,
1127 	int p_buf_len)
1128 {
1129 	unsigned char buf[VPD_TMP_BUF_SIZE];
1130 	int ret = 0;
1131 	int len;
1132 
1133 	memset(buf, 0, VPD_TMP_BUF_SIZE);
1134 	len = sprintf(buf, "T10 VPD Identifier Type: ");
1135 
1136 	switch (vpd->device_identifier_type) {
1137 	case 0x00:
1138 		sprintf(buf+len, "Vendor specific\n");
1139 		break;
1140 	case 0x01:
1141 		sprintf(buf+len, "T10 Vendor ID based\n");
1142 		break;
1143 	case 0x02:
1144 		sprintf(buf+len, "EUI-64 based\n");
1145 		break;
1146 	case 0x03:
1147 		sprintf(buf+len, "NAA\n");
1148 		break;
1149 	case 0x04:
1150 		sprintf(buf+len, "Relative target port identifier\n");
1151 		break;
1152 	case 0x08:
1153 		sprintf(buf+len, "SCSI name string\n");
1154 		break;
1155 	default:
1156 		sprintf(buf+len, "Unsupported: 0x%02x\n",
1157 				vpd->device_identifier_type);
1158 		ret = -EINVAL;
1159 		break;
1160 	}
1161 
1162 	if (p_buf) {
1163 		if (p_buf_len < strlen(buf)+1)
1164 			return -EINVAL;
1165 		strncpy(p_buf, buf, p_buf_len);
1166 	} else {
1167 		pr_debug("%s", buf);
1168 	}
1169 
1170 	return ret;
1171 }
1172 
1173 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1174 {
1175 	/*
1176 	 * The VPD identifier type..
1177 	 *
1178 	 * from spc3r23.pdf Section 7.6.3.1 Table 298
1179 	 */
1180 	vpd->device_identifier_type = (page_83[1] & 0x0f);
1181 	return transport_dump_vpd_ident_type(vpd, NULL, 0);
1182 }
1183 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1184 
1185 int transport_dump_vpd_ident(
1186 	struct t10_vpd *vpd,
1187 	unsigned char *p_buf,
1188 	int p_buf_len)
1189 {
1190 	unsigned char buf[VPD_TMP_BUF_SIZE];
1191 	int ret = 0;
1192 
1193 	memset(buf, 0, VPD_TMP_BUF_SIZE);
1194 
1195 	switch (vpd->device_identifier_code_set) {
1196 	case 0x01: /* Binary */
1197 		sprintf(buf, "T10 VPD Binary Device Identifier: %s\n",
1198 			&vpd->device_identifier[0]);
1199 		break;
1200 	case 0x02: /* ASCII */
1201 		sprintf(buf, "T10 VPD ASCII Device Identifier: %s\n",
1202 			&vpd->device_identifier[0]);
1203 		break;
1204 	case 0x03: /* UTF-8 */
1205 		sprintf(buf, "T10 VPD UTF-8 Device Identifier: %s\n",
1206 			&vpd->device_identifier[0]);
1207 		break;
1208 	default:
1209 		sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1210 			" 0x%02x", vpd->device_identifier_code_set);
1211 		ret = -EINVAL;
1212 		break;
1213 	}
1214 
1215 	if (p_buf)
1216 		strncpy(p_buf, buf, p_buf_len);
1217 	else
1218 		pr_debug("%s", buf);
1219 
1220 	return ret;
1221 }
1222 
1223 int
1224 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1225 {
1226 	static const char hex_str[] = "0123456789abcdef";
1227 	int j = 0, i = 4; /* offset to start of the identifer */
1228 
1229 	/*
1230 	 * The VPD Code Set (encoding)
1231 	 *
1232 	 * from spc3r23.pdf Section 7.6.3.1 Table 296
1233 	 */
1234 	vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1235 	switch (vpd->device_identifier_code_set) {
1236 	case 0x01: /* Binary */
1237 		vpd->device_identifier[j++] =
1238 				hex_str[vpd->device_identifier_type];
1239 		while (i < (4 + page_83[3])) {
1240 			vpd->device_identifier[j++] =
1241 				hex_str[(page_83[i] & 0xf0) >> 4];
1242 			vpd->device_identifier[j++] =
1243 				hex_str[page_83[i] & 0x0f];
1244 			i++;
1245 		}
1246 		break;
1247 	case 0x02: /* ASCII */
1248 	case 0x03: /* UTF-8 */
1249 		while (i < (4 + page_83[3]))
1250 			vpd->device_identifier[j++] = page_83[i++];
1251 		break;
1252 	default:
1253 		break;
1254 	}
1255 
1256 	return transport_dump_vpd_ident(vpd, NULL, 0);
1257 }
1258 EXPORT_SYMBOL(transport_set_vpd_ident);
1259 
1260 static void core_setup_task_attr_emulation(struct se_device *dev)
1261 {
1262 	/*
1263 	 * If this device is from Target_Core_Mod/pSCSI, disable the
1264 	 * SAM Task Attribute emulation.
1265 	 *
1266 	 * This is currently not available in upsream Linux/SCSI Target
1267 	 * mode code, and is assumed to be disabled while using TCM/pSCSI.
1268 	 */
1269 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) {
1270 		dev->dev_task_attr_type = SAM_TASK_ATTR_PASSTHROUGH;
1271 		return;
1272 	}
1273 
1274 	dev->dev_task_attr_type = SAM_TASK_ATTR_EMULATED;
1275 	pr_debug("%s: Using SAM_TASK_ATTR_EMULATED for SPC: 0x%02x"
1276 		" device\n", dev->transport->name,
1277 		dev->transport->get_device_rev(dev));
1278 }
1279 
1280 static void scsi_dump_inquiry(struct se_device *dev)
1281 {
1282 	struct t10_wwn *wwn = &dev->se_sub_dev->t10_wwn;
1283 	char buf[17];
1284 	int i, device_type;
1285 	/*
1286 	 * Print Linux/SCSI style INQUIRY formatting to the kernel ring buffer
1287 	 */
1288 	for (i = 0; i < 8; i++)
1289 		if (wwn->vendor[i] >= 0x20)
1290 			buf[i] = wwn->vendor[i];
1291 		else
1292 			buf[i] = ' ';
1293 	buf[i] = '\0';
1294 	pr_debug("  Vendor: %s\n", buf);
1295 
1296 	for (i = 0; i < 16; i++)
1297 		if (wwn->model[i] >= 0x20)
1298 			buf[i] = wwn->model[i];
1299 		else
1300 			buf[i] = ' ';
1301 	buf[i] = '\0';
1302 	pr_debug("  Model: %s\n", buf);
1303 
1304 	for (i = 0; i < 4; i++)
1305 		if (wwn->revision[i] >= 0x20)
1306 			buf[i] = wwn->revision[i];
1307 		else
1308 			buf[i] = ' ';
1309 	buf[i] = '\0';
1310 	pr_debug("  Revision: %s\n", buf);
1311 
1312 	device_type = dev->transport->get_device_type(dev);
1313 	pr_debug("  Type:   %s ", scsi_device_type(device_type));
1314 	pr_debug("                 ANSI SCSI revision: %02x\n",
1315 				dev->transport->get_device_rev(dev));
1316 }
1317 
1318 struct se_device *transport_add_device_to_core_hba(
1319 	struct se_hba *hba,
1320 	struct se_subsystem_api *transport,
1321 	struct se_subsystem_dev *se_dev,
1322 	u32 device_flags,
1323 	void *transport_dev,
1324 	struct se_dev_limits *dev_limits,
1325 	const char *inquiry_prod,
1326 	const char *inquiry_rev)
1327 {
1328 	int force_pt;
1329 	struct se_device  *dev;
1330 
1331 	dev = kzalloc(sizeof(struct se_device), GFP_KERNEL);
1332 	if (!dev) {
1333 		pr_err("Unable to allocate memory for se_dev_t\n");
1334 		return NULL;
1335 	}
1336 
1337 	transport_init_queue_obj(&dev->dev_queue_obj);
1338 	dev->dev_flags		= device_flags;
1339 	dev->dev_status		|= TRANSPORT_DEVICE_DEACTIVATED;
1340 	dev->dev_ptr		= transport_dev;
1341 	dev->se_hba		= hba;
1342 	dev->se_sub_dev		= se_dev;
1343 	dev->transport		= transport;
1344 	INIT_LIST_HEAD(&dev->dev_list);
1345 	INIT_LIST_HEAD(&dev->dev_sep_list);
1346 	INIT_LIST_HEAD(&dev->dev_tmr_list);
1347 	INIT_LIST_HEAD(&dev->execute_task_list);
1348 	INIT_LIST_HEAD(&dev->delayed_cmd_list);
1349 	INIT_LIST_HEAD(&dev->state_task_list);
1350 	INIT_LIST_HEAD(&dev->qf_cmd_list);
1351 	spin_lock_init(&dev->execute_task_lock);
1352 	spin_lock_init(&dev->delayed_cmd_lock);
1353 	spin_lock_init(&dev->dev_reservation_lock);
1354 	spin_lock_init(&dev->dev_status_lock);
1355 	spin_lock_init(&dev->se_port_lock);
1356 	spin_lock_init(&dev->se_tmr_lock);
1357 	spin_lock_init(&dev->qf_cmd_lock);
1358 	atomic_set(&dev->dev_ordered_id, 0);
1359 
1360 	se_dev_set_default_attribs(dev, dev_limits);
1361 
1362 	dev->dev_index = scsi_get_new_index(SCSI_DEVICE_INDEX);
1363 	dev->creation_time = get_jiffies_64();
1364 	spin_lock_init(&dev->stats_lock);
1365 
1366 	spin_lock(&hba->device_lock);
1367 	list_add_tail(&dev->dev_list, &hba->hba_dev_list);
1368 	hba->dev_count++;
1369 	spin_unlock(&hba->device_lock);
1370 	/*
1371 	 * Setup the SAM Task Attribute emulation for struct se_device
1372 	 */
1373 	core_setup_task_attr_emulation(dev);
1374 	/*
1375 	 * Force PR and ALUA passthrough emulation with internal object use.
1376 	 */
1377 	force_pt = (hba->hba_flags & HBA_FLAGS_INTERNAL_USE);
1378 	/*
1379 	 * Setup the Reservations infrastructure for struct se_device
1380 	 */
1381 	core_setup_reservations(dev, force_pt);
1382 	/*
1383 	 * Setup the Asymmetric Logical Unit Assignment for struct se_device
1384 	 */
1385 	if (core_setup_alua(dev, force_pt) < 0)
1386 		goto out;
1387 
1388 	/*
1389 	 * Startup the struct se_device processing thread
1390 	 */
1391 	dev->process_thread = kthread_run(transport_processing_thread, dev,
1392 					  "LIO_%s", dev->transport->name);
1393 	if (IS_ERR(dev->process_thread)) {
1394 		pr_err("Unable to create kthread: LIO_%s\n",
1395 			dev->transport->name);
1396 		goto out;
1397 	}
1398 	/*
1399 	 * Setup work_queue for QUEUE_FULL
1400 	 */
1401 	INIT_WORK(&dev->qf_work_queue, target_qf_do_work);
1402 	/*
1403 	 * Preload the initial INQUIRY const values if we are doing
1404 	 * anything virtual (IBLOCK, FILEIO, RAMDISK), but not for TCM/pSCSI
1405 	 * passthrough because this is being provided by the backend LLD.
1406 	 * This is required so that transport_get_inquiry() copies these
1407 	 * originals once back into DEV_T10_WWN(dev) for the virtual device
1408 	 * setup.
1409 	 */
1410 	if (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) {
1411 		if (!inquiry_prod || !inquiry_rev) {
1412 			pr_err("All non TCM/pSCSI plugins require"
1413 				" INQUIRY consts\n");
1414 			goto out;
1415 		}
1416 
1417 		strncpy(&dev->se_sub_dev->t10_wwn.vendor[0], "LIO-ORG", 8);
1418 		strncpy(&dev->se_sub_dev->t10_wwn.model[0], inquiry_prod, 16);
1419 		strncpy(&dev->se_sub_dev->t10_wwn.revision[0], inquiry_rev, 4);
1420 	}
1421 	scsi_dump_inquiry(dev);
1422 
1423 	return dev;
1424 out:
1425 	kthread_stop(dev->process_thread);
1426 
1427 	spin_lock(&hba->device_lock);
1428 	list_del(&dev->dev_list);
1429 	hba->dev_count--;
1430 	spin_unlock(&hba->device_lock);
1431 
1432 	se_release_vpd_for_dev(dev);
1433 
1434 	kfree(dev);
1435 
1436 	return NULL;
1437 }
1438 EXPORT_SYMBOL(transport_add_device_to_core_hba);
1439 
1440 /*	transport_generic_prepare_cdb():
1441  *
1442  *	Since the Initiator sees iSCSI devices as LUNs,  the SCSI CDB will
1443  *	contain the iSCSI LUN in bits 7-5 of byte 1 as per SAM-2.
1444  *	The point of this is since we are mapping iSCSI LUNs to
1445  *	SCSI Target IDs having a non-zero LUN in the CDB will throw the
1446  *	devices and HBAs for a loop.
1447  */
1448 static inline void transport_generic_prepare_cdb(
1449 	unsigned char *cdb)
1450 {
1451 	switch (cdb[0]) {
1452 	case READ_10: /* SBC - RDProtect */
1453 	case READ_12: /* SBC - RDProtect */
1454 	case READ_16: /* SBC - RDProtect */
1455 	case SEND_DIAGNOSTIC: /* SPC - SELF-TEST Code */
1456 	case VERIFY: /* SBC - VRProtect */
1457 	case VERIFY_16: /* SBC - VRProtect */
1458 	case WRITE_VERIFY: /* SBC - VRProtect */
1459 	case WRITE_VERIFY_12: /* SBC - VRProtect */
1460 		break;
1461 	default:
1462 		cdb[1] &= 0x1f; /* clear logical unit number */
1463 		break;
1464 	}
1465 }
1466 
1467 static struct se_task *
1468 transport_generic_get_task(struct se_cmd *cmd,
1469 		enum dma_data_direction data_direction)
1470 {
1471 	struct se_task *task;
1472 	struct se_device *dev = cmd->se_dev;
1473 
1474 	task = dev->transport->alloc_task(cmd->t_task_cdb);
1475 	if (!task) {
1476 		pr_err("Unable to allocate struct se_task\n");
1477 		return NULL;
1478 	}
1479 
1480 	INIT_LIST_HEAD(&task->t_list);
1481 	INIT_LIST_HEAD(&task->t_execute_list);
1482 	INIT_LIST_HEAD(&task->t_state_list);
1483 	init_completion(&task->task_stop_comp);
1484 	task->task_se_cmd = cmd;
1485 	task->task_data_direction = data_direction;
1486 
1487 	return task;
1488 }
1489 
1490 static int transport_generic_cmd_sequencer(struct se_cmd *, unsigned char *);
1491 
1492 /*
1493  * Used by fabric modules containing a local struct se_cmd within their
1494  * fabric dependent per I/O descriptor.
1495  */
1496 void transport_init_se_cmd(
1497 	struct se_cmd *cmd,
1498 	struct target_core_fabric_ops *tfo,
1499 	struct se_session *se_sess,
1500 	u32 data_length,
1501 	int data_direction,
1502 	int task_attr,
1503 	unsigned char *sense_buffer)
1504 {
1505 	INIT_LIST_HEAD(&cmd->se_lun_node);
1506 	INIT_LIST_HEAD(&cmd->se_delayed_node);
1507 	INIT_LIST_HEAD(&cmd->se_qf_node);
1508 	INIT_LIST_HEAD(&cmd->se_queue_node);
1509 	INIT_LIST_HEAD(&cmd->se_cmd_list);
1510 	INIT_LIST_HEAD(&cmd->t_task_list);
1511 	init_completion(&cmd->transport_lun_fe_stop_comp);
1512 	init_completion(&cmd->transport_lun_stop_comp);
1513 	init_completion(&cmd->t_transport_stop_comp);
1514 	init_completion(&cmd->cmd_wait_comp);
1515 	spin_lock_init(&cmd->t_state_lock);
1516 	cmd->transport_state = CMD_T_DEV_ACTIVE;
1517 
1518 	cmd->se_tfo = tfo;
1519 	cmd->se_sess = se_sess;
1520 	cmd->data_length = data_length;
1521 	cmd->data_direction = data_direction;
1522 	cmd->sam_task_attr = task_attr;
1523 	cmd->sense_buffer = sense_buffer;
1524 }
1525 EXPORT_SYMBOL(transport_init_se_cmd);
1526 
1527 static int transport_check_alloc_task_attr(struct se_cmd *cmd)
1528 {
1529 	/*
1530 	 * Check if SAM Task Attribute emulation is enabled for this
1531 	 * struct se_device storage object
1532 	 */
1533 	if (cmd->se_dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED)
1534 		return 0;
1535 
1536 	if (cmd->sam_task_attr == MSG_ACA_TAG) {
1537 		pr_debug("SAM Task Attribute ACA"
1538 			" emulation is not supported\n");
1539 		return -EINVAL;
1540 	}
1541 	/*
1542 	 * Used to determine when ORDERED commands should go from
1543 	 * Dormant to Active status.
1544 	 */
1545 	cmd->se_ordered_id = atomic_inc_return(&cmd->se_dev->dev_ordered_id);
1546 	smp_mb__after_atomic_inc();
1547 	pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1548 			cmd->se_ordered_id, cmd->sam_task_attr,
1549 			cmd->se_dev->transport->name);
1550 	return 0;
1551 }
1552 
1553 /*	transport_generic_allocate_tasks():
1554  *
1555  *	Called from fabric RX Thread.
1556  */
1557 int transport_generic_allocate_tasks(
1558 	struct se_cmd *cmd,
1559 	unsigned char *cdb)
1560 {
1561 	int ret;
1562 
1563 	transport_generic_prepare_cdb(cdb);
1564 	/*
1565 	 * Ensure that the received CDB is less than the max (252 + 8) bytes
1566 	 * for VARIABLE_LENGTH_CMD
1567 	 */
1568 	if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1569 		pr_err("Received SCSI CDB with command_size: %d that"
1570 			" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1571 			scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1572 		cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1573 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
1574 		return -EINVAL;
1575 	}
1576 	/*
1577 	 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1578 	 * allocate the additional extended CDB buffer now..  Otherwise
1579 	 * setup the pointer from __t_task_cdb to t_task_cdb.
1580 	 */
1581 	if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1582 		cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1583 						GFP_KERNEL);
1584 		if (!cmd->t_task_cdb) {
1585 			pr_err("Unable to allocate cmd->t_task_cdb"
1586 				" %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1587 				scsi_command_size(cdb),
1588 				(unsigned long)sizeof(cmd->__t_task_cdb));
1589 			cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1590 			cmd->scsi_sense_reason =
1591 					TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1592 			return -ENOMEM;
1593 		}
1594 	} else
1595 		cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1596 	/*
1597 	 * Copy the original CDB into cmd->
1598 	 */
1599 	memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1600 	/*
1601 	 * Setup the received CDB based on SCSI defined opcodes and
1602 	 * perform unit attention, persistent reservations and ALUA
1603 	 * checks for virtual device backends.  The cmd->t_task_cdb
1604 	 * pointer is expected to be setup before we reach this point.
1605 	 */
1606 	ret = transport_generic_cmd_sequencer(cmd, cdb);
1607 	if (ret < 0)
1608 		return ret;
1609 	/*
1610 	 * Check for SAM Task Attribute Emulation
1611 	 */
1612 	if (transport_check_alloc_task_attr(cmd) < 0) {
1613 		cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1614 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
1615 		return -EINVAL;
1616 	}
1617 	spin_lock(&cmd->se_lun->lun_sep_lock);
1618 	if (cmd->se_lun->lun_sep)
1619 		cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1620 	spin_unlock(&cmd->se_lun->lun_sep_lock);
1621 	return 0;
1622 }
1623 EXPORT_SYMBOL(transport_generic_allocate_tasks);
1624 
1625 /*
1626  * Used by fabric module frontends to queue tasks directly.
1627  * Many only be used from process context only
1628  */
1629 int transport_handle_cdb_direct(
1630 	struct se_cmd *cmd)
1631 {
1632 	int ret;
1633 
1634 	if (!cmd->se_lun) {
1635 		dump_stack();
1636 		pr_err("cmd->se_lun is NULL\n");
1637 		return -EINVAL;
1638 	}
1639 	if (in_interrupt()) {
1640 		dump_stack();
1641 		pr_err("transport_generic_handle_cdb cannot be called"
1642 				" from interrupt context\n");
1643 		return -EINVAL;
1644 	}
1645 	/*
1646 	 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE following
1647 	 * transport_generic_handle_cdb*() -> transport_add_cmd_to_queue()
1648 	 * in existing usage to ensure that outstanding descriptors are handled
1649 	 * correctly during shutdown via transport_wait_for_tasks()
1650 	 *
1651 	 * Also, we don't take cmd->t_state_lock here as we only expect
1652 	 * this to be called for initial descriptor submission.
1653 	 */
1654 	cmd->t_state = TRANSPORT_NEW_CMD;
1655 	cmd->transport_state |= CMD_T_ACTIVE;
1656 
1657 	/*
1658 	 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1659 	 * so follow TRANSPORT_NEW_CMD processing thread context usage
1660 	 * and call transport_generic_request_failure() if necessary..
1661 	 */
1662 	ret = transport_generic_new_cmd(cmd);
1663 	if (ret < 0)
1664 		transport_generic_request_failure(cmd);
1665 
1666 	return 0;
1667 }
1668 EXPORT_SYMBOL(transport_handle_cdb_direct);
1669 
1670 /**
1671  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1672  *
1673  * @se_cmd: command descriptor to submit
1674  * @se_sess: associated se_sess for endpoint
1675  * @cdb: pointer to SCSI CDB
1676  * @sense: pointer to SCSI sense buffer
1677  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1678  * @data_length: fabric expected data transfer length
1679  * @task_addr: SAM task attribute
1680  * @data_dir: DMA data direction
1681  * @flags: flags for command submission from target_sc_flags_tables
1682  *
1683  * This may only be called from process context, and also currently
1684  * assumes internal allocation of fabric payload buffer by target-core.
1685  **/
1686 void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1687 		unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1688 		u32 data_length, int task_attr, int data_dir, int flags)
1689 {
1690 	struct se_portal_group *se_tpg;
1691 	int rc;
1692 
1693 	se_tpg = se_sess->se_tpg;
1694 	BUG_ON(!se_tpg);
1695 	BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1696 	BUG_ON(in_interrupt());
1697 	/*
1698 	 * Initialize se_cmd for target operation.  From this point
1699 	 * exceptions are handled by sending exception status via
1700 	 * target_core_fabric_ops->queue_status() callback
1701 	 */
1702 	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1703 				data_length, data_dir, task_attr, sense);
1704 	/*
1705 	 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1706 	 * se_sess->sess_cmd_list.  A second kref_get here is necessary
1707 	 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1708 	 * kref_put() to happen during fabric packet acknowledgement.
1709 	 */
1710 	target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1711 	/*
1712 	 * Signal bidirectional data payloads to target-core
1713 	 */
1714 	if (flags & TARGET_SCF_BIDI_OP)
1715 		se_cmd->se_cmd_flags |= SCF_BIDI;
1716 	/*
1717 	 * Locate se_lun pointer and attach it to struct se_cmd
1718 	 */
1719 	if (transport_lookup_cmd_lun(se_cmd, unpacked_lun) < 0) {
1720 		transport_send_check_condition_and_sense(se_cmd,
1721 				se_cmd->scsi_sense_reason, 0);
1722 		target_put_sess_cmd(se_sess, se_cmd);
1723 		return;
1724 	}
1725 	/*
1726 	 * Sanitize CDBs via transport_generic_cmd_sequencer() and
1727 	 * allocate the necessary tasks to complete the received CDB+data
1728 	 */
1729 	rc = transport_generic_allocate_tasks(se_cmd, cdb);
1730 	if (rc != 0) {
1731 		transport_generic_request_failure(se_cmd);
1732 		return;
1733 	}
1734 	/*
1735 	 * Dispatch se_cmd descriptor to se_lun->lun_se_dev backend
1736 	 * for immediate execution of READs, otherwise wait for
1737 	 * transport_generic_handle_data() to be called for WRITEs
1738 	 * when fabric has filled the incoming buffer.
1739 	 */
1740 	transport_handle_cdb_direct(se_cmd);
1741 	return;
1742 }
1743 EXPORT_SYMBOL(target_submit_cmd);
1744 
1745 static void target_complete_tmr_failure(struct work_struct *work)
1746 {
1747 	struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1748 
1749 	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1750 	se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1751 	transport_generic_free_cmd(se_cmd, 0);
1752 }
1753 
1754 /**
1755  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1756  *                     for TMR CDBs
1757  *
1758  * @se_cmd: command descriptor to submit
1759  * @se_sess: associated se_sess for endpoint
1760  * @sense: pointer to SCSI sense buffer
1761  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1762  * @fabric_context: fabric context for TMR req
1763  * @tm_type: Type of TM request
1764  * @gfp: gfp type for caller
1765  * @tag: referenced task tag for TMR_ABORT_TASK
1766  * @flags: submit cmd flags
1767  *
1768  * Callable from all contexts.
1769  **/
1770 
1771 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1772 		unsigned char *sense, u32 unpacked_lun,
1773 		void *fabric_tmr_ptr, unsigned char tm_type,
1774 		gfp_t gfp, unsigned int tag, int flags)
1775 {
1776 	struct se_portal_group *se_tpg;
1777 	int ret;
1778 
1779 	se_tpg = se_sess->se_tpg;
1780 	BUG_ON(!se_tpg);
1781 
1782 	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1783 			      0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1784 	/*
1785 	 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1786 	 * allocation failure.
1787 	 */
1788 	ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1789 	if (ret < 0)
1790 		return -ENOMEM;
1791 
1792 	if (tm_type == TMR_ABORT_TASK)
1793 		se_cmd->se_tmr_req->ref_task_tag = tag;
1794 
1795 	/* See target_submit_cmd for commentary */
1796 	target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1797 
1798 	ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1799 	if (ret) {
1800 		/*
1801 		 * For callback during failure handling, push this work off
1802 		 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1803 		 */
1804 		INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1805 		schedule_work(&se_cmd->work);
1806 		return 0;
1807 	}
1808 	transport_generic_handle_tmr(se_cmd);
1809 	return 0;
1810 }
1811 EXPORT_SYMBOL(target_submit_tmr);
1812 
1813 /*
1814  * Used by fabric module frontends defining a TFO->new_cmd_map() caller
1815  * to  queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD_MAP in order to
1816  * complete setup in TCM process context w/ TFO->new_cmd_map().
1817  */
1818 int transport_generic_handle_cdb_map(
1819 	struct se_cmd *cmd)
1820 {
1821 	if (!cmd->se_lun) {
1822 		dump_stack();
1823 		pr_err("cmd->se_lun is NULL\n");
1824 		return -EINVAL;
1825 	}
1826 
1827 	transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD_MAP, false);
1828 	return 0;
1829 }
1830 EXPORT_SYMBOL(transport_generic_handle_cdb_map);
1831 
1832 /*	transport_generic_handle_data():
1833  *
1834  *
1835  */
1836 int transport_generic_handle_data(
1837 	struct se_cmd *cmd)
1838 {
1839 	/*
1840 	 * For the software fabric case, then we assume the nexus is being
1841 	 * failed/shutdown when signals are pending from the kthread context
1842 	 * caller, so we return a failure.  For the HW target mode case running
1843 	 * in interrupt code, the signal_pending() check is skipped.
1844 	 */
1845 	if (!in_interrupt() && signal_pending(current))
1846 		return -EPERM;
1847 	/*
1848 	 * If the received CDB has aleady been ABORTED by the generic
1849 	 * target engine, we now call transport_check_aborted_status()
1850 	 * to queue any delated TASK_ABORTED status for the received CDB to the
1851 	 * fabric module as we are expecting no further incoming DATA OUT
1852 	 * sequences at this point.
1853 	 */
1854 	if (transport_check_aborted_status(cmd, 1) != 0)
1855 		return 0;
1856 
1857 	transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_WRITE, false);
1858 	return 0;
1859 }
1860 EXPORT_SYMBOL(transport_generic_handle_data);
1861 
1862 /*	transport_generic_handle_tmr():
1863  *
1864  *
1865  */
1866 int transport_generic_handle_tmr(
1867 	struct se_cmd *cmd)
1868 {
1869 	transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_TMR, false);
1870 	return 0;
1871 }
1872 EXPORT_SYMBOL(transport_generic_handle_tmr);
1873 
1874 /*
1875  * If the task is active, request it to be stopped and sleep until it
1876  * has completed.
1877  */
1878 bool target_stop_task(struct se_task *task, unsigned long *flags)
1879 {
1880 	struct se_cmd *cmd = task->task_se_cmd;
1881 	bool was_active = false;
1882 
1883 	if (task->task_flags & TF_ACTIVE) {
1884 		task->task_flags |= TF_REQUEST_STOP;
1885 		spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1886 
1887 		pr_debug("Task %p waiting to complete\n", task);
1888 		wait_for_completion(&task->task_stop_comp);
1889 		pr_debug("Task %p stopped successfully\n", task);
1890 
1891 		spin_lock_irqsave(&cmd->t_state_lock, *flags);
1892 		atomic_dec(&cmd->t_task_cdbs_left);
1893 		task->task_flags &= ~(TF_ACTIVE | TF_REQUEST_STOP);
1894 		was_active = true;
1895 	}
1896 
1897 	return was_active;
1898 }
1899 
1900 static int transport_stop_tasks_for_cmd(struct se_cmd *cmd)
1901 {
1902 	struct se_task *task, *task_tmp;
1903 	unsigned long flags;
1904 	int ret = 0;
1905 
1906 	pr_debug("ITT[0x%08x] - Stopping tasks\n",
1907 		cmd->se_tfo->get_task_tag(cmd));
1908 
1909 	/*
1910 	 * No tasks remain in the execution queue
1911 	 */
1912 	spin_lock_irqsave(&cmd->t_state_lock, flags);
1913 	list_for_each_entry_safe(task, task_tmp,
1914 				&cmd->t_task_list, t_list) {
1915 		pr_debug("Processing task %p\n", task);
1916 		/*
1917 		 * If the struct se_task has not been sent and is not active,
1918 		 * remove the struct se_task from the execution queue.
1919 		 */
1920 		if (!(task->task_flags & (TF_ACTIVE | TF_SENT))) {
1921 			spin_unlock_irqrestore(&cmd->t_state_lock,
1922 					flags);
1923 			transport_remove_task_from_execute_queue(task,
1924 					cmd->se_dev);
1925 
1926 			pr_debug("Task %p removed from execute queue\n", task);
1927 			spin_lock_irqsave(&cmd->t_state_lock, flags);
1928 			continue;
1929 		}
1930 
1931 		if (!target_stop_task(task, &flags)) {
1932 			pr_debug("Task %p - did nothing\n", task);
1933 			ret++;
1934 		}
1935 	}
1936 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1937 
1938 	return ret;
1939 }
1940 
1941 /*
1942  * Handle SAM-esque emulation for generic transport request failures.
1943  */
1944 void transport_generic_request_failure(struct se_cmd *cmd)
1945 {
1946 	int ret = 0;
1947 
1948 	pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1949 		" CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1950 		cmd->t_task_cdb[0]);
1951 	pr_debug("-----[ i_state: %d t_state: %d scsi_sense_reason: %d\n",
1952 		cmd->se_tfo->get_cmd_state(cmd),
1953 		cmd->t_state, cmd->scsi_sense_reason);
1954 	pr_debug("-----[ t_tasks: %d t_task_cdbs_left: %d"
1955 		" t_task_cdbs_sent: %d t_task_cdbs_ex_left: %d --"
1956 		" CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1957 		cmd->t_task_list_num,
1958 		atomic_read(&cmd->t_task_cdbs_left),
1959 		atomic_read(&cmd->t_task_cdbs_sent),
1960 		atomic_read(&cmd->t_task_cdbs_ex_left),
1961 		(cmd->transport_state & CMD_T_ACTIVE) != 0,
1962 		(cmd->transport_state & CMD_T_STOP) != 0,
1963 		(cmd->transport_state & CMD_T_SENT) != 0);
1964 
1965 	/*
1966 	 * For SAM Task Attribute emulation for failed struct se_cmd
1967 	 */
1968 	if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
1969 		transport_complete_task_attr(cmd);
1970 
1971 	switch (cmd->scsi_sense_reason) {
1972 	case TCM_NON_EXISTENT_LUN:
1973 	case TCM_UNSUPPORTED_SCSI_OPCODE:
1974 	case TCM_INVALID_CDB_FIELD:
1975 	case TCM_INVALID_PARAMETER_LIST:
1976 	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1977 	case TCM_UNKNOWN_MODE_PAGE:
1978 	case TCM_WRITE_PROTECTED:
1979 	case TCM_CHECK_CONDITION_ABORT_CMD:
1980 	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1981 	case TCM_CHECK_CONDITION_NOT_READY:
1982 		break;
1983 	case TCM_RESERVATION_CONFLICT:
1984 		/*
1985 		 * No SENSE Data payload for this case, set SCSI Status
1986 		 * and queue the response to $FABRIC_MOD.
1987 		 *
1988 		 * Uses linux/include/scsi/scsi.h SAM status codes defs
1989 		 */
1990 		cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1991 		/*
1992 		 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1993 		 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1994 		 * CONFLICT STATUS.
1995 		 *
1996 		 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1997 		 */
1998 		if (cmd->se_sess &&
1999 		    cmd->se_dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 2)
2000 			core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
2001 				cmd->orig_fe_lun, 0x2C,
2002 				ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
2003 
2004 		ret = cmd->se_tfo->queue_status(cmd);
2005 		if (ret == -EAGAIN || ret == -ENOMEM)
2006 			goto queue_full;
2007 		goto check_stop;
2008 	default:
2009 		pr_err("Unknown transport error for CDB 0x%02x: %d\n",
2010 			cmd->t_task_cdb[0], cmd->scsi_sense_reason);
2011 		cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
2012 		break;
2013 	}
2014 	/*
2015 	 * If a fabric does not define a cmd->se_tfo->new_cmd_map caller,
2016 	 * make the call to transport_send_check_condition_and_sense()
2017 	 * directly.  Otherwise expect the fabric to make the call to
2018 	 * transport_send_check_condition_and_sense() after handling
2019 	 * possible unsoliticied write data payloads.
2020 	 */
2021 	ret = transport_send_check_condition_and_sense(cmd,
2022 			cmd->scsi_sense_reason, 0);
2023 	if (ret == -EAGAIN || ret == -ENOMEM)
2024 		goto queue_full;
2025 
2026 check_stop:
2027 	transport_lun_remove_cmd(cmd);
2028 	if (!transport_cmd_check_stop_to_fabric(cmd))
2029 		;
2030 	return;
2031 
2032 queue_full:
2033 	cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2034 	transport_handle_queue_full(cmd, cmd->se_dev);
2035 }
2036 EXPORT_SYMBOL(transport_generic_request_failure);
2037 
2038 static inline u32 transport_lba_21(unsigned char *cdb)
2039 {
2040 	return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
2041 }
2042 
2043 static inline u32 transport_lba_32(unsigned char *cdb)
2044 {
2045 	return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
2046 }
2047 
2048 static inline unsigned long long transport_lba_64(unsigned char *cdb)
2049 {
2050 	unsigned int __v1, __v2;
2051 
2052 	__v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
2053 	__v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
2054 
2055 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
2056 }
2057 
2058 /*
2059  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
2060  */
2061 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
2062 {
2063 	unsigned int __v1, __v2;
2064 
2065 	__v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
2066 	__v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
2067 
2068 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
2069 }
2070 
2071 static void transport_set_supported_SAM_opcode(struct se_cmd *se_cmd)
2072 {
2073 	unsigned long flags;
2074 
2075 	spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2076 	se_cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
2077 	spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2078 }
2079 
2080 /*
2081  * Called from Fabric Module context from transport_execute_tasks()
2082  *
2083  * The return of this function determins if the tasks from struct se_cmd
2084  * get added to the execution queue in transport_execute_tasks(),
2085  * or are added to the delayed or ordered lists here.
2086  */
2087 static inline int transport_execute_task_attr(struct se_cmd *cmd)
2088 {
2089 	if (cmd->se_dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED)
2090 		return 1;
2091 	/*
2092 	 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
2093 	 * to allow the passed struct se_cmd list of tasks to the front of the list.
2094 	 */
2095 	 if (cmd->sam_task_attr == MSG_HEAD_TAG) {
2096 		pr_debug("Added HEAD_OF_QUEUE for CDB:"
2097 			" 0x%02x, se_ordered_id: %u\n",
2098 			cmd->t_task_cdb[0],
2099 			cmd->se_ordered_id);
2100 		return 1;
2101 	} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
2102 		atomic_inc(&cmd->se_dev->dev_ordered_sync);
2103 		smp_mb__after_atomic_inc();
2104 
2105 		pr_debug("Added ORDERED for CDB: 0x%02x to ordered"
2106 				" list, se_ordered_id: %u\n",
2107 				cmd->t_task_cdb[0],
2108 				cmd->se_ordered_id);
2109 		/*
2110 		 * Add ORDERED command to tail of execution queue if
2111 		 * no other older commands exist that need to be
2112 		 * completed first.
2113 		 */
2114 		if (!atomic_read(&cmd->se_dev->simple_cmds))
2115 			return 1;
2116 	} else {
2117 		/*
2118 		 * For SIMPLE and UNTAGGED Task Attribute commands
2119 		 */
2120 		atomic_inc(&cmd->se_dev->simple_cmds);
2121 		smp_mb__after_atomic_inc();
2122 	}
2123 	/*
2124 	 * Otherwise if one or more outstanding ORDERED task attribute exist,
2125 	 * add the dormant task(s) built for the passed struct se_cmd to the
2126 	 * execution queue and become in Active state for this struct se_device.
2127 	 */
2128 	if (atomic_read(&cmd->se_dev->dev_ordered_sync) != 0) {
2129 		/*
2130 		 * Otherwise, add cmd w/ tasks to delayed cmd queue that
2131 		 * will be drained upon completion of HEAD_OF_QUEUE task.
2132 		 */
2133 		spin_lock(&cmd->se_dev->delayed_cmd_lock);
2134 		cmd->se_cmd_flags |= SCF_DELAYED_CMD_FROM_SAM_ATTR;
2135 		list_add_tail(&cmd->se_delayed_node,
2136 				&cmd->se_dev->delayed_cmd_list);
2137 		spin_unlock(&cmd->se_dev->delayed_cmd_lock);
2138 
2139 		pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
2140 			" delayed CMD list, se_ordered_id: %u\n",
2141 			cmd->t_task_cdb[0], cmd->sam_task_attr,
2142 			cmd->se_ordered_id);
2143 		/*
2144 		 * Return zero to let transport_execute_tasks() know
2145 		 * not to add the delayed tasks to the execution list.
2146 		 */
2147 		return 0;
2148 	}
2149 	/*
2150 	 * Otherwise, no ORDERED task attributes exist..
2151 	 */
2152 	return 1;
2153 }
2154 
2155 /*
2156  * Called from fabric module context in transport_generic_new_cmd() and
2157  * transport_generic_process_write()
2158  */
2159 static int transport_execute_tasks(struct se_cmd *cmd)
2160 {
2161 	int add_tasks;
2162 	struct se_device *se_dev = cmd->se_dev;
2163 	/*
2164 	 * Call transport_cmd_check_stop() to see if a fabric exception
2165 	 * has occurred that prevents execution.
2166 	 */
2167 	if (!transport_cmd_check_stop(cmd, 0, TRANSPORT_PROCESSING)) {
2168 		/*
2169 		 * Check for SAM Task Attribute emulation and HEAD_OF_QUEUE
2170 		 * attribute for the tasks of the received struct se_cmd CDB
2171 		 */
2172 		add_tasks = transport_execute_task_attr(cmd);
2173 		if (!add_tasks)
2174 			goto execute_tasks;
2175 		/*
2176 		 * __transport_execute_tasks() -> __transport_add_tasks_from_cmd()
2177 		 * adds associated se_tasks while holding dev->execute_task_lock
2178 		 * before I/O dispath to avoid a double spinlock access.
2179 		 */
2180 		__transport_execute_tasks(se_dev, cmd);
2181 		return 0;
2182 	}
2183 
2184 execute_tasks:
2185 	__transport_execute_tasks(se_dev, NULL);
2186 	return 0;
2187 }
2188 
2189 /*
2190  * Called to check struct se_device tcq depth window, and once open pull struct se_task
2191  * from struct se_device->execute_task_list and
2192  *
2193  * Called from transport_processing_thread()
2194  */
2195 static int __transport_execute_tasks(struct se_device *dev, struct se_cmd *new_cmd)
2196 {
2197 	int error;
2198 	struct se_cmd *cmd = NULL;
2199 	struct se_task *task = NULL;
2200 	unsigned long flags;
2201 
2202 check_depth:
2203 	spin_lock_irq(&dev->execute_task_lock);
2204 	if (new_cmd != NULL)
2205 		__transport_add_tasks_from_cmd(new_cmd);
2206 
2207 	if (list_empty(&dev->execute_task_list)) {
2208 		spin_unlock_irq(&dev->execute_task_lock);
2209 		return 0;
2210 	}
2211 	task = list_first_entry(&dev->execute_task_list,
2212 				struct se_task, t_execute_list);
2213 	__transport_remove_task_from_execute_queue(task, dev);
2214 	spin_unlock_irq(&dev->execute_task_lock);
2215 
2216 	cmd = task->task_se_cmd;
2217 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2218 	task->task_flags |= (TF_ACTIVE | TF_SENT);
2219 	atomic_inc(&cmd->t_task_cdbs_sent);
2220 
2221 	if (atomic_read(&cmd->t_task_cdbs_sent) ==
2222 	    cmd->t_task_list_num)
2223 		cmd->transport_state |= CMD_T_SENT;
2224 
2225 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2226 
2227 	if (cmd->execute_task)
2228 		error = cmd->execute_task(task);
2229 	else
2230 		error = dev->transport->do_task(task);
2231 	if (error != 0) {
2232 		spin_lock_irqsave(&cmd->t_state_lock, flags);
2233 		task->task_flags &= ~TF_ACTIVE;
2234 		cmd->transport_state &= ~CMD_T_SENT;
2235 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2236 
2237 		transport_stop_tasks_for_cmd(cmd);
2238 		transport_generic_request_failure(cmd);
2239 	}
2240 
2241 	new_cmd = NULL;
2242 	goto check_depth;
2243 
2244 	return 0;
2245 }
2246 
2247 static inline u32 transport_get_sectors_6(
2248 	unsigned char *cdb,
2249 	struct se_cmd *cmd,
2250 	int *ret)
2251 {
2252 	struct se_device *dev = cmd->se_dev;
2253 
2254 	/*
2255 	 * Assume TYPE_DISK for non struct se_device objects.
2256 	 * Use 8-bit sector value.
2257 	 */
2258 	if (!dev)
2259 		goto type_disk;
2260 
2261 	/*
2262 	 * Use 24-bit allocation length for TYPE_TAPE.
2263 	 */
2264 	if (dev->transport->get_device_type(dev) == TYPE_TAPE)
2265 		return (u32)(cdb[2] << 16) + (cdb[3] << 8) + cdb[4];
2266 
2267 	/*
2268 	 * Everything else assume TYPE_DISK Sector CDB location.
2269 	 * Use 8-bit sector value.  SBC-3 says:
2270 	 *
2271 	 *   A TRANSFER LENGTH field set to zero specifies that 256
2272 	 *   logical blocks shall be written.  Any other value
2273 	 *   specifies the number of logical blocks that shall be
2274 	 *   written.
2275 	 */
2276 type_disk:
2277 	return cdb[4] ? : 256;
2278 }
2279 
2280 static inline u32 transport_get_sectors_10(
2281 	unsigned char *cdb,
2282 	struct se_cmd *cmd,
2283 	int *ret)
2284 {
2285 	struct se_device *dev = cmd->se_dev;
2286 
2287 	/*
2288 	 * Assume TYPE_DISK for non struct se_device objects.
2289 	 * Use 16-bit sector value.
2290 	 */
2291 	if (!dev)
2292 		goto type_disk;
2293 
2294 	/*
2295 	 * XXX_10 is not defined in SSC, throw an exception
2296 	 */
2297 	if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2298 		*ret = -EINVAL;
2299 		return 0;
2300 	}
2301 
2302 	/*
2303 	 * Everything else assume TYPE_DISK Sector CDB location.
2304 	 * Use 16-bit sector value.
2305 	 */
2306 type_disk:
2307 	return (u32)(cdb[7] << 8) + cdb[8];
2308 }
2309 
2310 static inline u32 transport_get_sectors_12(
2311 	unsigned char *cdb,
2312 	struct se_cmd *cmd,
2313 	int *ret)
2314 {
2315 	struct se_device *dev = cmd->se_dev;
2316 
2317 	/*
2318 	 * Assume TYPE_DISK for non struct se_device objects.
2319 	 * Use 32-bit sector value.
2320 	 */
2321 	if (!dev)
2322 		goto type_disk;
2323 
2324 	/*
2325 	 * XXX_12 is not defined in SSC, throw an exception
2326 	 */
2327 	if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2328 		*ret = -EINVAL;
2329 		return 0;
2330 	}
2331 
2332 	/*
2333 	 * Everything else assume TYPE_DISK Sector CDB location.
2334 	 * Use 32-bit sector value.
2335 	 */
2336 type_disk:
2337 	return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
2338 }
2339 
2340 static inline u32 transport_get_sectors_16(
2341 	unsigned char *cdb,
2342 	struct se_cmd *cmd,
2343 	int *ret)
2344 {
2345 	struct se_device *dev = cmd->se_dev;
2346 
2347 	/*
2348 	 * Assume TYPE_DISK for non struct se_device objects.
2349 	 * Use 32-bit sector value.
2350 	 */
2351 	if (!dev)
2352 		goto type_disk;
2353 
2354 	/*
2355 	 * Use 24-bit allocation length for TYPE_TAPE.
2356 	 */
2357 	if (dev->transport->get_device_type(dev) == TYPE_TAPE)
2358 		return (u32)(cdb[12] << 16) + (cdb[13] << 8) + cdb[14];
2359 
2360 type_disk:
2361 	return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
2362 		    (cdb[12] << 8) + cdb[13];
2363 }
2364 
2365 /*
2366  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
2367  */
2368 static inline u32 transport_get_sectors_32(
2369 	unsigned char *cdb,
2370 	struct se_cmd *cmd,
2371 	int *ret)
2372 {
2373 	/*
2374 	 * Assume TYPE_DISK for non struct se_device objects.
2375 	 * Use 32-bit sector value.
2376 	 */
2377 	return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
2378 		    (cdb[30] << 8) + cdb[31];
2379 
2380 }
2381 
2382 static inline u32 transport_get_size(
2383 	u32 sectors,
2384 	unsigned char *cdb,
2385 	struct se_cmd *cmd)
2386 {
2387 	struct se_device *dev = cmd->se_dev;
2388 
2389 	if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2390 		if (cdb[1] & 1) { /* sectors */
2391 			return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
2392 		} else /* bytes */
2393 			return sectors;
2394 	}
2395 #if 0
2396 	pr_debug("Returning block_size: %u, sectors: %u == %u for"
2397 			" %s object\n", dev->se_sub_dev->se_dev_attrib.block_size, sectors,
2398 			dev->se_sub_dev->se_dev_attrib.block_size * sectors,
2399 			dev->transport->name);
2400 #endif
2401 	return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
2402 }
2403 
2404 static void transport_xor_callback(struct se_cmd *cmd)
2405 {
2406 	unsigned char *buf, *addr;
2407 	struct scatterlist *sg;
2408 	unsigned int offset;
2409 	int i;
2410 	int count;
2411 	/*
2412 	 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
2413 	 *
2414 	 * 1) read the specified logical block(s);
2415 	 * 2) transfer logical blocks from the data-out buffer;
2416 	 * 3) XOR the logical blocks transferred from the data-out buffer with
2417 	 *    the logical blocks read, storing the resulting XOR data in a buffer;
2418 	 * 4) if the DISABLE WRITE bit is set to zero, then write the logical
2419 	 *    blocks transferred from the data-out buffer; and
2420 	 * 5) transfer the resulting XOR data to the data-in buffer.
2421 	 */
2422 	buf = kmalloc(cmd->data_length, GFP_KERNEL);
2423 	if (!buf) {
2424 		pr_err("Unable to allocate xor_callback buf\n");
2425 		return;
2426 	}
2427 	/*
2428 	 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
2429 	 * into the locally allocated *buf
2430 	 */
2431 	sg_copy_to_buffer(cmd->t_data_sg,
2432 			  cmd->t_data_nents,
2433 			  buf,
2434 			  cmd->data_length);
2435 
2436 	/*
2437 	 * Now perform the XOR against the BIDI read memory located at
2438 	 * cmd->t_mem_bidi_list
2439 	 */
2440 
2441 	offset = 0;
2442 	for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
2443 		addr = kmap_atomic(sg_page(sg));
2444 		if (!addr)
2445 			goto out;
2446 
2447 		for (i = 0; i < sg->length; i++)
2448 			*(addr + sg->offset + i) ^= *(buf + offset + i);
2449 
2450 		offset += sg->length;
2451 		kunmap_atomic(addr);
2452 	}
2453 
2454 out:
2455 	kfree(buf);
2456 }
2457 
2458 /*
2459  * Used to obtain Sense Data from underlying Linux/SCSI struct scsi_cmnd
2460  */
2461 static int transport_get_sense_data(struct se_cmd *cmd)
2462 {
2463 	unsigned char *buffer = cmd->sense_buffer, *sense_buffer = NULL;
2464 	struct se_device *dev = cmd->se_dev;
2465 	struct se_task *task = NULL, *task_tmp;
2466 	unsigned long flags;
2467 	u32 offset = 0;
2468 
2469 	WARN_ON(!cmd->se_lun);
2470 
2471 	if (!dev)
2472 		return 0;
2473 
2474 	spin_lock_irqsave(&cmd->t_state_lock, flags);
2475 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2476 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2477 		return 0;
2478 	}
2479 
2480 	list_for_each_entry_safe(task, task_tmp,
2481 				&cmd->t_task_list, t_list) {
2482 		if (!(task->task_flags & TF_HAS_SENSE))
2483 			continue;
2484 
2485 		if (!dev->transport->get_sense_buffer) {
2486 			pr_err("dev->transport->get_sense_buffer"
2487 					" is NULL\n");
2488 			continue;
2489 		}
2490 
2491 		sense_buffer = dev->transport->get_sense_buffer(task);
2492 		if (!sense_buffer) {
2493 			pr_err("ITT[0x%08x]_TASK[%p]: Unable to locate"
2494 				" sense buffer for task with sense\n",
2495 				cmd->se_tfo->get_task_tag(cmd), task);
2496 			continue;
2497 		}
2498 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2499 
2500 		offset = cmd->se_tfo->set_fabric_sense_len(cmd,
2501 				TRANSPORT_SENSE_BUFFER);
2502 
2503 		memcpy(&buffer[offset], sense_buffer,
2504 				TRANSPORT_SENSE_BUFFER);
2505 		cmd->scsi_status = task->task_scsi_status;
2506 		/* Automatically padded */
2507 		cmd->scsi_sense_length =
2508 				(TRANSPORT_SENSE_BUFFER + offset);
2509 
2510 		pr_debug("HBA_[%u]_PLUG[%s]: Set SAM STATUS: 0x%02x"
2511 				" and sense\n",
2512 			dev->se_hba->hba_id, dev->transport->name,
2513 				cmd->scsi_status);
2514 		return 0;
2515 	}
2516 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2517 
2518 	return -1;
2519 }
2520 
2521 static inline long long transport_dev_end_lba(struct se_device *dev)
2522 {
2523 	return dev->transport->get_blocks(dev) + 1;
2524 }
2525 
2526 static int transport_cmd_get_valid_sectors(struct se_cmd *cmd)
2527 {
2528 	struct se_device *dev = cmd->se_dev;
2529 	u32 sectors;
2530 
2531 	if (dev->transport->get_device_type(dev) != TYPE_DISK)
2532 		return 0;
2533 
2534 	sectors = (cmd->data_length / dev->se_sub_dev->se_dev_attrib.block_size);
2535 
2536 	if ((cmd->t_task_lba + sectors) > transport_dev_end_lba(dev)) {
2537 		pr_err("LBA: %llu Sectors: %u exceeds"
2538 			" transport_dev_end_lba(): %llu\n",
2539 			cmd->t_task_lba, sectors,
2540 			transport_dev_end_lba(dev));
2541 		return -EINVAL;
2542 	}
2543 
2544 	return 0;
2545 }
2546 
2547 static int target_check_write_same_discard(unsigned char *flags, struct se_device *dev)
2548 {
2549 	/*
2550 	 * Determine if the received WRITE_SAME is used to for direct
2551 	 * passthrough into Linux/SCSI with struct request via TCM/pSCSI
2552 	 * or we are signaling the use of internal WRITE_SAME + UNMAP=1
2553 	 * emulation for -> Linux/BLOCK disbard with TCM/IBLOCK code.
2554 	 */
2555 	int passthrough = (dev->transport->transport_type ==
2556 				TRANSPORT_PLUGIN_PHBA_PDEV);
2557 
2558 	if (!passthrough) {
2559 		if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
2560 			pr_err("WRITE_SAME PBDATA and LBDATA"
2561 				" bits not supported for Block Discard"
2562 				" Emulation\n");
2563 			return -ENOSYS;
2564 		}
2565 		/*
2566 		 * Currently for the emulated case we only accept
2567 		 * tpws with the UNMAP=1 bit set.
2568 		 */
2569 		if (!(flags[0] & 0x08)) {
2570 			pr_err("WRITE_SAME w/o UNMAP bit not"
2571 				" supported for Block Discard Emulation\n");
2572 			return -ENOSYS;
2573 		}
2574 	}
2575 
2576 	return 0;
2577 }
2578 
2579 /*	transport_generic_cmd_sequencer():
2580  *
2581  *	Generic Command Sequencer that should work for most DAS transport
2582  *	drivers.
2583  *
2584  *	Called from transport_generic_allocate_tasks() in the $FABRIC_MOD
2585  *	RX Thread.
2586  *
2587  *	FIXME: Need to support other SCSI OPCODES where as well.
2588  */
2589 static int transport_generic_cmd_sequencer(
2590 	struct se_cmd *cmd,
2591 	unsigned char *cdb)
2592 {
2593 	struct se_device *dev = cmd->se_dev;
2594 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
2595 	int ret = 0, sector_ret = 0, passthrough;
2596 	u32 sectors = 0, size = 0, pr_reg_type = 0;
2597 	u16 service_action;
2598 	u8 alua_ascq = 0;
2599 	/*
2600 	 * Check for an existing UNIT ATTENTION condition
2601 	 */
2602 	if (core_scsi3_ua_check(cmd, cdb) < 0) {
2603 		cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2604 		cmd->scsi_sense_reason = TCM_CHECK_CONDITION_UNIT_ATTENTION;
2605 		return -EINVAL;
2606 	}
2607 	/*
2608 	 * Check status of Asymmetric Logical Unit Assignment port
2609 	 */
2610 	ret = su_dev->t10_alua.alua_state_check(cmd, cdb, &alua_ascq);
2611 	if (ret != 0) {
2612 		/*
2613 		 * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
2614 		 * The ALUA additional sense code qualifier (ASCQ) is determined
2615 		 * by the ALUA primary or secondary access state..
2616 		 */
2617 		if (ret > 0) {
2618 #if 0
2619 			pr_debug("[%s]: ALUA TG Port not available,"
2620 				" SenseKey: NOT_READY, ASC/ASCQ: 0x04/0x%02x\n",
2621 				cmd->se_tfo->get_fabric_name(), alua_ascq);
2622 #endif
2623 			transport_set_sense_codes(cmd, 0x04, alua_ascq);
2624 			cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2625 			cmd->scsi_sense_reason = TCM_CHECK_CONDITION_NOT_READY;
2626 			return -EINVAL;
2627 		}
2628 		goto out_invalid_cdb_field;
2629 	}
2630 	/*
2631 	 * Check status for SPC-3 Persistent Reservations
2632 	 */
2633 	if (su_dev->t10_pr.pr_ops.t10_reservation_check(cmd, &pr_reg_type) != 0) {
2634 		if (su_dev->t10_pr.pr_ops.t10_seq_non_holder(
2635 					cmd, cdb, pr_reg_type) != 0) {
2636 			cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2637 			cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT;
2638 			cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
2639 			cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2640 			return -EBUSY;
2641 		}
2642 		/*
2643 		 * This means the CDB is allowed for the SCSI Initiator port
2644 		 * when said port is *NOT* holding the legacy SPC-2 or
2645 		 * SPC-3 Persistent Reservation.
2646 		 */
2647 	}
2648 
2649 	/*
2650 	 * If we operate in passthrough mode we skip most CDB emulation and
2651 	 * instead hand the commands down to the physical SCSI device.
2652 	 */
2653 	passthrough =
2654 		(dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV);
2655 
2656 	switch (cdb[0]) {
2657 	case READ_6:
2658 		sectors = transport_get_sectors_6(cdb, cmd, &sector_ret);
2659 		if (sector_ret)
2660 			goto out_unsupported_cdb;
2661 		size = transport_get_size(sectors, cdb, cmd);
2662 		cmd->t_task_lba = transport_lba_21(cdb);
2663 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2664 		break;
2665 	case READ_10:
2666 		sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2667 		if (sector_ret)
2668 			goto out_unsupported_cdb;
2669 		size = transport_get_size(sectors, cdb, cmd);
2670 		cmd->t_task_lba = transport_lba_32(cdb);
2671 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2672 		break;
2673 	case READ_12:
2674 		sectors = transport_get_sectors_12(cdb, cmd, &sector_ret);
2675 		if (sector_ret)
2676 			goto out_unsupported_cdb;
2677 		size = transport_get_size(sectors, cdb, cmd);
2678 		cmd->t_task_lba = transport_lba_32(cdb);
2679 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2680 		break;
2681 	case READ_16:
2682 		sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2683 		if (sector_ret)
2684 			goto out_unsupported_cdb;
2685 		size = transport_get_size(sectors, cdb, cmd);
2686 		cmd->t_task_lba = transport_lba_64(cdb);
2687 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2688 		break;
2689 	case WRITE_6:
2690 		sectors = transport_get_sectors_6(cdb, cmd, &sector_ret);
2691 		if (sector_ret)
2692 			goto out_unsupported_cdb;
2693 		size = transport_get_size(sectors, cdb, cmd);
2694 		cmd->t_task_lba = transport_lba_21(cdb);
2695 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2696 		break;
2697 	case WRITE_10:
2698 		sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2699 		if (sector_ret)
2700 			goto out_unsupported_cdb;
2701 		size = transport_get_size(sectors, cdb, cmd);
2702 		cmd->t_task_lba = transport_lba_32(cdb);
2703 		if (cdb[1] & 0x8)
2704 			cmd->se_cmd_flags |= SCF_FUA;
2705 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2706 		break;
2707 	case WRITE_12:
2708 		sectors = transport_get_sectors_12(cdb, cmd, &sector_ret);
2709 		if (sector_ret)
2710 			goto out_unsupported_cdb;
2711 		size = transport_get_size(sectors, cdb, cmd);
2712 		cmd->t_task_lba = transport_lba_32(cdb);
2713 		if (cdb[1] & 0x8)
2714 			cmd->se_cmd_flags |= SCF_FUA;
2715 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2716 		break;
2717 	case WRITE_16:
2718 		sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2719 		if (sector_ret)
2720 			goto out_unsupported_cdb;
2721 		size = transport_get_size(sectors, cdb, cmd);
2722 		cmd->t_task_lba = transport_lba_64(cdb);
2723 		if (cdb[1] & 0x8)
2724 			cmd->se_cmd_flags |= SCF_FUA;
2725 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2726 		break;
2727 	case XDWRITEREAD_10:
2728 		if ((cmd->data_direction != DMA_TO_DEVICE) ||
2729 		    !(cmd->se_cmd_flags & SCF_BIDI))
2730 			goto out_invalid_cdb_field;
2731 		sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2732 		if (sector_ret)
2733 			goto out_unsupported_cdb;
2734 		size = transport_get_size(sectors, cdb, cmd);
2735 		cmd->t_task_lba = transport_lba_32(cdb);
2736 		cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2737 
2738 		/*
2739 		 * Do now allow BIDI commands for passthrough mode.
2740 		 */
2741 		if (passthrough)
2742 			goto out_unsupported_cdb;
2743 
2744 		/*
2745 		 * Setup BIDI XOR callback to be run after I/O completion.
2746 		 */
2747 		cmd->transport_complete_callback = &transport_xor_callback;
2748 		if (cdb[1] & 0x8)
2749 			cmd->se_cmd_flags |= SCF_FUA;
2750 		break;
2751 	case VARIABLE_LENGTH_CMD:
2752 		service_action = get_unaligned_be16(&cdb[8]);
2753 		switch (service_action) {
2754 		case XDWRITEREAD_32:
2755 			sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
2756 			if (sector_ret)
2757 				goto out_unsupported_cdb;
2758 			size = transport_get_size(sectors, cdb, cmd);
2759 			/*
2760 			 * Use WRITE_32 and READ_32 opcodes for the emulated
2761 			 * XDWRITE_READ_32 logic.
2762 			 */
2763 			cmd->t_task_lba = transport_lba_64_ext(cdb);
2764 			cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2765 
2766 			/*
2767 			 * Do now allow BIDI commands for passthrough mode.
2768 			 */
2769 			if (passthrough)
2770 				goto out_unsupported_cdb;
2771 
2772 			/*
2773 			 * Setup BIDI XOR callback to be run during after I/O
2774 			 * completion.
2775 			 */
2776 			cmd->transport_complete_callback = &transport_xor_callback;
2777 			if (cdb[1] & 0x8)
2778 				cmd->se_cmd_flags |= SCF_FUA;
2779 			break;
2780 		case WRITE_SAME_32:
2781 			sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
2782 			if (sector_ret)
2783 				goto out_unsupported_cdb;
2784 
2785 			if (sectors)
2786 				size = transport_get_size(1, cdb, cmd);
2787 			else {
2788 				pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
2789 				       " supported\n");
2790 				goto out_invalid_cdb_field;
2791 			}
2792 
2793 			cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
2794 			cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2795 
2796 			if (target_check_write_same_discard(&cdb[10], dev) < 0)
2797 				goto out_unsupported_cdb;
2798 			if (!passthrough)
2799 				cmd->execute_task = target_emulate_write_same;
2800 			break;
2801 		default:
2802 			pr_err("VARIABLE_LENGTH_CMD service action"
2803 				" 0x%04x not supported\n", service_action);
2804 			goto out_unsupported_cdb;
2805 		}
2806 		break;
2807 	case MAINTENANCE_IN:
2808 		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
2809 			/* MAINTENANCE_IN from SCC-2 */
2810 			/*
2811 			 * Check for emulated MI_REPORT_TARGET_PGS.
2812 			 */
2813 			if (cdb[1] == MI_REPORT_TARGET_PGS &&
2814 			    su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
2815 				cmd->execute_task =
2816 					target_emulate_report_target_port_groups;
2817 			}
2818 			size = (cdb[6] << 24) | (cdb[7] << 16) |
2819 			       (cdb[8] << 8) | cdb[9];
2820 		} else {
2821 			/* GPCMD_SEND_KEY from multi media commands */
2822 			size = (cdb[8] << 8) + cdb[9];
2823 		}
2824 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2825 		break;
2826 	case MODE_SELECT:
2827 		size = cdb[4];
2828 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2829 		break;
2830 	case MODE_SELECT_10:
2831 		size = (cdb[7] << 8) + cdb[8];
2832 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2833 		break;
2834 	case MODE_SENSE:
2835 		size = cdb[4];
2836 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2837 		if (!passthrough)
2838 			cmd->execute_task = target_emulate_modesense;
2839 		break;
2840 	case MODE_SENSE_10:
2841 		size = (cdb[7] << 8) + cdb[8];
2842 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2843 		if (!passthrough)
2844 			cmd->execute_task = target_emulate_modesense;
2845 		break;
2846 	case GPCMD_READ_BUFFER_CAPACITY:
2847 	case GPCMD_SEND_OPC:
2848 	case LOG_SELECT:
2849 	case LOG_SENSE:
2850 		size = (cdb[7] << 8) + cdb[8];
2851 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2852 		break;
2853 	case READ_BLOCK_LIMITS:
2854 		size = READ_BLOCK_LEN;
2855 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2856 		break;
2857 	case GPCMD_GET_CONFIGURATION:
2858 	case GPCMD_READ_FORMAT_CAPACITIES:
2859 	case GPCMD_READ_DISC_INFO:
2860 	case GPCMD_READ_TRACK_RZONE_INFO:
2861 		size = (cdb[7] << 8) + cdb[8];
2862 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2863 		break;
2864 	case PERSISTENT_RESERVE_IN:
2865 		if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
2866 			cmd->execute_task = target_scsi3_emulate_pr_in;
2867 		size = (cdb[7] << 8) + cdb[8];
2868 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2869 		break;
2870 	case PERSISTENT_RESERVE_OUT:
2871 		if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
2872 			cmd->execute_task = target_scsi3_emulate_pr_out;
2873 		size = (cdb[7] << 8) + cdb[8];
2874 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2875 		break;
2876 	case GPCMD_MECHANISM_STATUS:
2877 	case GPCMD_READ_DVD_STRUCTURE:
2878 		size = (cdb[8] << 8) + cdb[9];
2879 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2880 		break;
2881 	case READ_POSITION:
2882 		size = READ_POSITION_LEN;
2883 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2884 		break;
2885 	case MAINTENANCE_OUT:
2886 		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
2887 			/* MAINTENANCE_OUT from SCC-2
2888 			 *
2889 			 * Check for emulated MO_SET_TARGET_PGS.
2890 			 */
2891 			if (cdb[1] == MO_SET_TARGET_PGS &&
2892 			    su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
2893 				cmd->execute_task =
2894 					target_emulate_set_target_port_groups;
2895 			}
2896 
2897 			size = (cdb[6] << 24) | (cdb[7] << 16) |
2898 			       (cdb[8] << 8) | cdb[9];
2899 		} else  {
2900 			/* GPCMD_REPORT_KEY from multi media commands */
2901 			size = (cdb[8] << 8) + cdb[9];
2902 		}
2903 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2904 		break;
2905 	case INQUIRY:
2906 		size = (cdb[3] << 8) + cdb[4];
2907 		/*
2908 		 * Do implict HEAD_OF_QUEUE processing for INQUIRY.
2909 		 * See spc4r17 section 5.3
2910 		 */
2911 		if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
2912 			cmd->sam_task_attr = MSG_HEAD_TAG;
2913 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2914 		if (!passthrough)
2915 			cmd->execute_task = target_emulate_inquiry;
2916 		break;
2917 	case READ_BUFFER:
2918 		size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
2919 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2920 		break;
2921 	case READ_CAPACITY:
2922 		size = READ_CAP_LEN;
2923 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2924 		if (!passthrough)
2925 			cmd->execute_task = target_emulate_readcapacity;
2926 		break;
2927 	case READ_MEDIA_SERIAL_NUMBER:
2928 	case SECURITY_PROTOCOL_IN:
2929 	case SECURITY_PROTOCOL_OUT:
2930 		size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
2931 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2932 		break;
2933 	case SERVICE_ACTION_IN:
2934 		switch (cmd->t_task_cdb[1] & 0x1f) {
2935 		case SAI_READ_CAPACITY_16:
2936 			if (!passthrough)
2937 				cmd->execute_task =
2938 					target_emulate_readcapacity_16;
2939 			break;
2940 		default:
2941 			if (passthrough)
2942 				break;
2943 
2944 			pr_err("Unsupported SA: 0x%02x\n",
2945 				cmd->t_task_cdb[1] & 0x1f);
2946 			goto out_invalid_cdb_field;
2947 		}
2948 		/*FALLTHROUGH*/
2949 	case ACCESS_CONTROL_IN:
2950 	case ACCESS_CONTROL_OUT:
2951 	case EXTENDED_COPY:
2952 	case READ_ATTRIBUTE:
2953 	case RECEIVE_COPY_RESULTS:
2954 	case WRITE_ATTRIBUTE:
2955 		size = (cdb[10] << 24) | (cdb[11] << 16) |
2956 		       (cdb[12] << 8) | cdb[13];
2957 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2958 		break;
2959 	case RECEIVE_DIAGNOSTIC:
2960 	case SEND_DIAGNOSTIC:
2961 		size = (cdb[3] << 8) | cdb[4];
2962 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2963 		break;
2964 /* #warning FIXME: Figure out correct GPCMD_READ_CD blocksize. */
2965 #if 0
2966 	case GPCMD_READ_CD:
2967 		sectors = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
2968 		size = (2336 * sectors);
2969 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2970 		break;
2971 #endif
2972 	case READ_TOC:
2973 		size = cdb[8];
2974 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2975 		break;
2976 	case REQUEST_SENSE:
2977 		size = cdb[4];
2978 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2979 		if (!passthrough)
2980 			cmd->execute_task = target_emulate_request_sense;
2981 		break;
2982 	case READ_ELEMENT_STATUS:
2983 		size = 65536 * cdb[7] + 256 * cdb[8] + cdb[9];
2984 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2985 		break;
2986 	case WRITE_BUFFER:
2987 		size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
2988 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2989 		break;
2990 	case RESERVE:
2991 	case RESERVE_10:
2992 		/*
2993 		 * The SPC-2 RESERVE does not contain a size in the SCSI CDB.
2994 		 * Assume the passthrough or $FABRIC_MOD will tell us about it.
2995 		 */
2996 		if (cdb[0] == RESERVE_10)
2997 			size = (cdb[7] << 8) | cdb[8];
2998 		else
2999 			size = cmd->data_length;
3000 
3001 		/*
3002 		 * Setup the legacy emulated handler for SPC-2 and
3003 		 * >= SPC-3 compatible reservation handling (CRH=1)
3004 		 * Otherwise, we assume the underlying SCSI logic is
3005 		 * is running in SPC_PASSTHROUGH, and wants reservations
3006 		 * emulation disabled.
3007 		 */
3008 		if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
3009 			cmd->execute_task = target_scsi2_reservation_reserve;
3010 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3011 		break;
3012 	case RELEASE:
3013 	case RELEASE_10:
3014 		/*
3015 		 * The SPC-2 RELEASE does not contain a size in the SCSI CDB.
3016 		 * Assume the passthrough or $FABRIC_MOD will tell us about it.
3017 		*/
3018 		if (cdb[0] == RELEASE_10)
3019 			size = (cdb[7] << 8) | cdb[8];
3020 		else
3021 			size = cmd->data_length;
3022 
3023 		if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
3024 			cmd->execute_task = target_scsi2_reservation_release;
3025 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3026 		break;
3027 	case SYNCHRONIZE_CACHE:
3028 	case SYNCHRONIZE_CACHE_16:
3029 		/*
3030 		 * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
3031 		 */
3032 		if (cdb[0] == SYNCHRONIZE_CACHE) {
3033 			sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
3034 			cmd->t_task_lba = transport_lba_32(cdb);
3035 		} else {
3036 			sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
3037 			cmd->t_task_lba = transport_lba_64(cdb);
3038 		}
3039 		if (sector_ret)
3040 			goto out_unsupported_cdb;
3041 
3042 		size = transport_get_size(sectors, cdb, cmd);
3043 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3044 
3045 		if (passthrough)
3046 			break;
3047 
3048 		/*
3049 		 * Check to ensure that LBA + Range does not exceed past end of
3050 		 * device for IBLOCK and FILEIO ->do_sync_cache() backend calls
3051 		 */
3052 		if ((cmd->t_task_lba != 0) || (sectors != 0)) {
3053 			if (transport_cmd_get_valid_sectors(cmd) < 0)
3054 				goto out_invalid_cdb_field;
3055 		}
3056 		cmd->execute_task = target_emulate_synchronize_cache;
3057 		break;
3058 	case UNMAP:
3059 		size = get_unaligned_be16(&cdb[7]);
3060 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3061 		if (!passthrough)
3062 			cmd->execute_task = target_emulate_unmap;
3063 		break;
3064 	case WRITE_SAME_16:
3065 		sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
3066 		if (sector_ret)
3067 			goto out_unsupported_cdb;
3068 
3069 		if (sectors)
3070 			size = transport_get_size(1, cdb, cmd);
3071 		else {
3072 			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
3073 			goto out_invalid_cdb_field;
3074 		}
3075 
3076 		cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
3077 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3078 
3079 		if (target_check_write_same_discard(&cdb[1], dev) < 0)
3080 			goto out_unsupported_cdb;
3081 		if (!passthrough)
3082 			cmd->execute_task = target_emulate_write_same;
3083 		break;
3084 	case WRITE_SAME:
3085 		sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
3086 		if (sector_ret)
3087 			goto out_unsupported_cdb;
3088 
3089 		if (sectors)
3090 			size = transport_get_size(1, cdb, cmd);
3091 		else {
3092 			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
3093 			goto out_invalid_cdb_field;
3094 		}
3095 
3096 		cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
3097 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3098 		/*
3099 		 * Follow sbcr26 with WRITE_SAME (10) and check for the existence
3100 		 * of byte 1 bit 3 UNMAP instead of original reserved field
3101 		 */
3102 		if (target_check_write_same_discard(&cdb[1], dev) < 0)
3103 			goto out_unsupported_cdb;
3104 		if (!passthrough)
3105 			cmd->execute_task = target_emulate_write_same;
3106 		break;
3107 	case ALLOW_MEDIUM_REMOVAL:
3108 	case ERASE:
3109 	case REZERO_UNIT:
3110 	case SEEK_10:
3111 	case SPACE:
3112 	case START_STOP:
3113 	case TEST_UNIT_READY:
3114 	case VERIFY:
3115 	case WRITE_FILEMARKS:
3116 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3117 		if (!passthrough)
3118 			cmd->execute_task = target_emulate_noop;
3119 		break;
3120 	case GPCMD_CLOSE_TRACK:
3121 	case INITIALIZE_ELEMENT_STATUS:
3122 	case GPCMD_LOAD_UNLOAD:
3123 	case GPCMD_SET_SPEED:
3124 	case MOVE_MEDIUM:
3125 		cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
3126 		break;
3127 	case REPORT_LUNS:
3128 		cmd->execute_task = target_report_luns;
3129 		size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
3130 		/*
3131 		 * Do implict HEAD_OF_QUEUE processing for REPORT_LUNS
3132 		 * See spc4r17 section 5.3
3133 		 */
3134 		if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3135 			cmd->sam_task_attr = MSG_HEAD_TAG;
3136 		cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3137 		break;
3138 	default:
3139 		pr_warn("TARGET_CORE[%s]: Unsupported SCSI Opcode"
3140 			" 0x%02x, sending CHECK_CONDITION.\n",
3141 			cmd->se_tfo->get_fabric_name(), cdb[0]);
3142 		goto out_unsupported_cdb;
3143 	}
3144 
3145 	if (size != cmd->data_length) {
3146 		pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
3147 			" %u does not match SCSI CDB Length: %u for SAM Opcode:"
3148 			" 0x%02x\n", cmd->se_tfo->get_fabric_name(),
3149 				cmd->data_length, size, cdb[0]);
3150 
3151 		cmd->cmd_spdtl = size;
3152 
3153 		if (cmd->data_direction == DMA_TO_DEVICE) {
3154 			pr_err("Rejecting underflow/overflow"
3155 					" WRITE data\n");
3156 			goto out_invalid_cdb_field;
3157 		}
3158 		/*
3159 		 * Reject READ_* or WRITE_* with overflow/underflow for
3160 		 * type SCF_SCSI_DATA_SG_IO_CDB.
3161 		 */
3162 		if (!ret && (dev->se_sub_dev->se_dev_attrib.block_size != 512))  {
3163 			pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
3164 				" CDB on non 512-byte sector setup subsystem"
3165 				" plugin: %s\n", dev->transport->name);
3166 			/* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
3167 			goto out_invalid_cdb_field;
3168 		}
3169 
3170 		if (size > cmd->data_length) {
3171 			cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
3172 			cmd->residual_count = (size - cmd->data_length);
3173 		} else {
3174 			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
3175 			cmd->residual_count = (cmd->data_length - size);
3176 		}
3177 		cmd->data_length = size;
3178 	}
3179 
3180 	if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB &&
3181 	    sectors > dev->se_sub_dev->se_dev_attrib.fabric_max_sectors) {
3182 		printk_ratelimited(KERN_ERR "SCSI OP %02xh with too big sectors %u\n",
3183 				   cdb[0], sectors);
3184 		goto out_invalid_cdb_field;
3185 	}
3186 
3187 	/* reject any command that we don't have a handler for */
3188 	if (!(passthrough || cmd->execute_task ||
3189 	     (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)))
3190 		goto out_unsupported_cdb;
3191 
3192 	transport_set_supported_SAM_opcode(cmd);
3193 	return ret;
3194 
3195 out_unsupported_cdb:
3196 	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3197 	cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
3198 	return -EINVAL;
3199 out_invalid_cdb_field:
3200 	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3201 	cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3202 	return -EINVAL;
3203 }
3204 
3205 /*
3206  * Called from I/O completion to determine which dormant/delayed
3207  * and ordered cmds need to have their tasks added to the execution queue.
3208  */
3209 static void transport_complete_task_attr(struct se_cmd *cmd)
3210 {
3211 	struct se_device *dev = cmd->se_dev;
3212 	struct se_cmd *cmd_p, *cmd_tmp;
3213 	int new_active_tasks = 0;
3214 
3215 	if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
3216 		atomic_dec(&dev->simple_cmds);
3217 		smp_mb__after_atomic_dec();
3218 		dev->dev_cur_ordered_id++;
3219 		pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
3220 			" SIMPLE: %u\n", dev->dev_cur_ordered_id,
3221 			cmd->se_ordered_id);
3222 	} else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
3223 		dev->dev_cur_ordered_id++;
3224 		pr_debug("Incremented dev_cur_ordered_id: %u for"
3225 			" HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
3226 			cmd->se_ordered_id);
3227 	} else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
3228 		atomic_dec(&dev->dev_ordered_sync);
3229 		smp_mb__after_atomic_dec();
3230 
3231 		dev->dev_cur_ordered_id++;
3232 		pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
3233 			" %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
3234 	}
3235 	/*
3236 	 * Process all commands up to the last received
3237 	 * ORDERED task attribute which requires another blocking
3238 	 * boundary
3239 	 */
3240 	spin_lock(&dev->delayed_cmd_lock);
3241 	list_for_each_entry_safe(cmd_p, cmd_tmp,
3242 			&dev->delayed_cmd_list, se_delayed_node) {
3243 
3244 		list_del(&cmd_p->se_delayed_node);
3245 		spin_unlock(&dev->delayed_cmd_lock);
3246 
3247 		pr_debug("Calling add_tasks() for"
3248 			" cmd_p: 0x%02x Task Attr: 0x%02x"
3249 			" Dormant -> Active, se_ordered_id: %u\n",
3250 			cmd_p->t_task_cdb[0],
3251 			cmd_p->sam_task_attr, cmd_p->se_ordered_id);
3252 
3253 		transport_add_tasks_from_cmd(cmd_p);
3254 		new_active_tasks++;
3255 
3256 		spin_lock(&dev->delayed_cmd_lock);
3257 		if (cmd_p->sam_task_attr == MSG_ORDERED_TAG)
3258 			break;
3259 	}
3260 	spin_unlock(&dev->delayed_cmd_lock);
3261 	/*
3262 	 * If new tasks have become active, wake up the transport thread
3263 	 * to do the processing of the Active tasks.
3264 	 */
3265 	if (new_active_tasks != 0)
3266 		wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
3267 }
3268 
3269 static void transport_complete_qf(struct se_cmd *cmd)
3270 {
3271 	int ret = 0;
3272 
3273 	if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3274 		transport_complete_task_attr(cmd);
3275 
3276 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
3277 		ret = cmd->se_tfo->queue_status(cmd);
3278 		if (ret)
3279 			goto out;
3280 	}
3281 
3282 	switch (cmd->data_direction) {
3283 	case DMA_FROM_DEVICE:
3284 		ret = cmd->se_tfo->queue_data_in(cmd);
3285 		break;
3286 	case DMA_TO_DEVICE:
3287 		if (cmd->t_bidi_data_sg) {
3288 			ret = cmd->se_tfo->queue_data_in(cmd);
3289 			if (ret < 0)
3290 				break;
3291 		}
3292 		/* Fall through for DMA_TO_DEVICE */
3293 	case DMA_NONE:
3294 		ret = cmd->se_tfo->queue_status(cmd);
3295 		break;
3296 	default:
3297 		break;
3298 	}
3299 
3300 out:
3301 	if (ret < 0) {
3302 		transport_handle_queue_full(cmd, cmd->se_dev);
3303 		return;
3304 	}
3305 	transport_lun_remove_cmd(cmd);
3306 	transport_cmd_check_stop_to_fabric(cmd);
3307 }
3308 
3309 static void transport_handle_queue_full(
3310 	struct se_cmd *cmd,
3311 	struct se_device *dev)
3312 {
3313 	spin_lock_irq(&dev->qf_cmd_lock);
3314 	list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
3315 	atomic_inc(&dev->dev_qf_count);
3316 	smp_mb__after_atomic_inc();
3317 	spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
3318 
3319 	schedule_work(&cmd->se_dev->qf_work_queue);
3320 }
3321 
3322 static void target_complete_ok_work(struct work_struct *work)
3323 {
3324 	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3325 	int reason = 0, ret;
3326 
3327 	/*
3328 	 * Check if we need to move delayed/dormant tasks from cmds on the
3329 	 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
3330 	 * Attribute.
3331 	 */
3332 	if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3333 		transport_complete_task_attr(cmd);
3334 	/*
3335 	 * Check to schedule QUEUE_FULL work, or execute an existing
3336 	 * cmd->transport_qf_callback()
3337 	 */
3338 	if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
3339 		schedule_work(&cmd->se_dev->qf_work_queue);
3340 
3341 	/*
3342 	 * Check if we need to retrieve a sense buffer from
3343 	 * the struct se_cmd in question.
3344 	 */
3345 	if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
3346 		if (transport_get_sense_data(cmd) < 0)
3347 			reason = TCM_NON_EXISTENT_LUN;
3348 
3349 		/*
3350 		 * Only set when an struct se_task->task_scsi_status returned
3351 		 * a non GOOD status.
3352 		 */
3353 		if (cmd->scsi_status) {
3354 			ret = transport_send_check_condition_and_sense(
3355 					cmd, reason, 1);
3356 			if (ret == -EAGAIN || ret == -ENOMEM)
3357 				goto queue_full;
3358 
3359 			transport_lun_remove_cmd(cmd);
3360 			transport_cmd_check_stop_to_fabric(cmd);
3361 			return;
3362 		}
3363 	}
3364 	/*
3365 	 * Check for a callback, used by amongst other things
3366 	 * XDWRITE_READ_10 emulation.
3367 	 */
3368 	if (cmd->transport_complete_callback)
3369 		cmd->transport_complete_callback(cmd);
3370 
3371 	switch (cmd->data_direction) {
3372 	case DMA_FROM_DEVICE:
3373 		spin_lock(&cmd->se_lun->lun_sep_lock);
3374 		if (cmd->se_lun->lun_sep) {
3375 			cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
3376 					cmd->data_length;
3377 		}
3378 		spin_unlock(&cmd->se_lun->lun_sep_lock);
3379 
3380 		ret = cmd->se_tfo->queue_data_in(cmd);
3381 		if (ret == -EAGAIN || ret == -ENOMEM)
3382 			goto queue_full;
3383 		break;
3384 	case DMA_TO_DEVICE:
3385 		spin_lock(&cmd->se_lun->lun_sep_lock);
3386 		if (cmd->se_lun->lun_sep) {
3387 			cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
3388 				cmd->data_length;
3389 		}
3390 		spin_unlock(&cmd->se_lun->lun_sep_lock);
3391 		/*
3392 		 * Check if we need to send READ payload for BIDI-COMMAND
3393 		 */
3394 		if (cmd->t_bidi_data_sg) {
3395 			spin_lock(&cmd->se_lun->lun_sep_lock);
3396 			if (cmd->se_lun->lun_sep) {
3397 				cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
3398 					cmd->data_length;
3399 			}
3400 			spin_unlock(&cmd->se_lun->lun_sep_lock);
3401 			ret = cmd->se_tfo->queue_data_in(cmd);
3402 			if (ret == -EAGAIN || ret == -ENOMEM)
3403 				goto queue_full;
3404 			break;
3405 		}
3406 		/* Fall through for DMA_TO_DEVICE */
3407 	case DMA_NONE:
3408 		ret = cmd->se_tfo->queue_status(cmd);
3409 		if (ret == -EAGAIN || ret == -ENOMEM)
3410 			goto queue_full;
3411 		break;
3412 	default:
3413 		break;
3414 	}
3415 
3416 	transport_lun_remove_cmd(cmd);
3417 	transport_cmd_check_stop_to_fabric(cmd);
3418 	return;
3419 
3420 queue_full:
3421 	pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
3422 		" data_direction: %d\n", cmd, cmd->data_direction);
3423 	cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
3424 	transport_handle_queue_full(cmd, cmd->se_dev);
3425 }
3426 
3427 static void transport_free_dev_tasks(struct se_cmd *cmd)
3428 {
3429 	struct se_task *task, *task_tmp;
3430 	unsigned long flags;
3431 	LIST_HEAD(dispose_list);
3432 
3433 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3434 	list_for_each_entry_safe(task, task_tmp,
3435 				&cmd->t_task_list, t_list) {
3436 		if (!(task->task_flags & TF_ACTIVE))
3437 			list_move_tail(&task->t_list, &dispose_list);
3438 	}
3439 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3440 
3441 	while (!list_empty(&dispose_list)) {
3442 		task = list_first_entry(&dispose_list, struct se_task, t_list);
3443 
3444 		if (task->task_sg != cmd->t_data_sg &&
3445 		    task->task_sg != cmd->t_bidi_data_sg)
3446 			kfree(task->task_sg);
3447 
3448 		list_del(&task->t_list);
3449 
3450 		cmd->se_dev->transport->free_task(task);
3451 	}
3452 }
3453 
3454 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
3455 {
3456 	struct scatterlist *sg;
3457 	int count;
3458 
3459 	for_each_sg(sgl, sg, nents, count)
3460 		__free_page(sg_page(sg));
3461 
3462 	kfree(sgl);
3463 }
3464 
3465 static inline void transport_free_pages(struct se_cmd *cmd)
3466 {
3467 	if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
3468 		return;
3469 
3470 	transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
3471 	cmd->t_data_sg = NULL;
3472 	cmd->t_data_nents = 0;
3473 
3474 	transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
3475 	cmd->t_bidi_data_sg = NULL;
3476 	cmd->t_bidi_data_nents = 0;
3477 }
3478 
3479 /**
3480  * transport_release_cmd - free a command
3481  * @cmd:       command to free
3482  *
3483  * This routine unconditionally frees a command, and reference counting
3484  * or list removal must be done in the caller.
3485  */
3486 static void transport_release_cmd(struct se_cmd *cmd)
3487 {
3488 	BUG_ON(!cmd->se_tfo);
3489 
3490 	if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
3491 		core_tmr_release_req(cmd->se_tmr_req);
3492 	if (cmd->t_task_cdb != cmd->__t_task_cdb)
3493 		kfree(cmd->t_task_cdb);
3494 	/*
3495 	 * If this cmd has been setup with target_get_sess_cmd(), drop
3496 	 * the kref and call ->release_cmd() in kref callback.
3497 	 */
3498 	 if (cmd->check_release != 0) {
3499 		target_put_sess_cmd(cmd->se_sess, cmd);
3500 		return;
3501 	}
3502 	cmd->se_tfo->release_cmd(cmd);
3503 }
3504 
3505 /**
3506  * transport_put_cmd - release a reference to a command
3507  * @cmd:       command to release
3508  *
3509  * This routine releases our reference to the command and frees it if possible.
3510  */
3511 static void transport_put_cmd(struct se_cmd *cmd)
3512 {
3513 	unsigned long flags;
3514 	int free_tasks = 0;
3515 
3516 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3517 	if (atomic_read(&cmd->t_fe_count)) {
3518 		if (!atomic_dec_and_test(&cmd->t_fe_count))
3519 			goto out_busy;
3520 	}
3521 
3522 	if (atomic_read(&cmd->t_se_count)) {
3523 		if (!atomic_dec_and_test(&cmd->t_se_count))
3524 			goto out_busy;
3525 	}
3526 
3527 	if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
3528 		cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
3529 		transport_all_task_dev_remove_state(cmd);
3530 		free_tasks = 1;
3531 	}
3532 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3533 
3534 	if (free_tasks != 0)
3535 		transport_free_dev_tasks(cmd);
3536 
3537 	transport_free_pages(cmd);
3538 	transport_release_cmd(cmd);
3539 	return;
3540 out_busy:
3541 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3542 }
3543 
3544 /*
3545  * transport_generic_map_mem_to_cmd - Use fabric-alloced pages instead of
3546  * allocating in the core.
3547  * @cmd:  Associated se_cmd descriptor
3548  * @mem:  SGL style memory for TCM WRITE / READ
3549  * @sg_mem_num: Number of SGL elements
3550  * @mem_bidi_in: SGL style memory for TCM BIDI READ
3551  * @sg_mem_bidi_num: Number of BIDI READ SGL elements
3552  *
3553  * Return: nonzero return cmd was rejected for -ENOMEM or inproper usage
3554  * of parameters.
3555  */
3556 int transport_generic_map_mem_to_cmd(
3557 	struct se_cmd *cmd,
3558 	struct scatterlist *sgl,
3559 	u32 sgl_count,
3560 	struct scatterlist *sgl_bidi,
3561 	u32 sgl_bidi_count)
3562 {
3563 	if (!sgl || !sgl_count)
3564 		return 0;
3565 
3566 	if ((cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) ||
3567 	    (cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB)) {
3568 		/*
3569 		 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
3570 		 * scatterlists already have been set to follow what the fabric
3571 		 * passes for the original expected data transfer length.
3572 		 */
3573 		if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
3574 			pr_warn("Rejecting SCSI DATA overflow for fabric using"
3575 				" SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
3576 			cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3577 			cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3578 			return -EINVAL;
3579 		}
3580 
3581 		cmd->t_data_sg = sgl;
3582 		cmd->t_data_nents = sgl_count;
3583 
3584 		if (sgl_bidi && sgl_bidi_count) {
3585 			cmd->t_bidi_data_sg = sgl_bidi;
3586 			cmd->t_bidi_data_nents = sgl_bidi_count;
3587 		}
3588 		cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
3589 	}
3590 
3591 	return 0;
3592 }
3593 EXPORT_SYMBOL(transport_generic_map_mem_to_cmd);
3594 
3595 void *transport_kmap_data_sg(struct se_cmd *cmd)
3596 {
3597 	struct scatterlist *sg = cmd->t_data_sg;
3598 	struct page **pages;
3599 	int i;
3600 
3601 	BUG_ON(!sg);
3602 	/*
3603 	 * We need to take into account a possible offset here for fabrics like
3604 	 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
3605 	 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
3606 	 */
3607 	if (!cmd->t_data_nents)
3608 		return NULL;
3609 	else if (cmd->t_data_nents == 1)
3610 		return kmap(sg_page(sg)) + sg->offset;
3611 
3612 	/* >1 page. use vmap */
3613 	pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
3614 	if (!pages)
3615 		return NULL;
3616 
3617 	/* convert sg[] to pages[] */
3618 	for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
3619 		pages[i] = sg_page(sg);
3620 	}
3621 
3622 	cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
3623 	kfree(pages);
3624 	if (!cmd->t_data_vmap)
3625 		return NULL;
3626 
3627 	return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
3628 }
3629 EXPORT_SYMBOL(transport_kmap_data_sg);
3630 
3631 void transport_kunmap_data_sg(struct se_cmd *cmd)
3632 {
3633 	if (!cmd->t_data_nents) {
3634 		return;
3635 	} else if (cmd->t_data_nents == 1) {
3636 		kunmap(sg_page(cmd->t_data_sg));
3637 		return;
3638 	}
3639 
3640 	vunmap(cmd->t_data_vmap);
3641 	cmd->t_data_vmap = NULL;
3642 }
3643 EXPORT_SYMBOL(transport_kunmap_data_sg);
3644 
3645 static int
3646 transport_generic_get_mem(struct se_cmd *cmd)
3647 {
3648 	u32 length = cmd->data_length;
3649 	unsigned int nents;
3650 	struct page *page;
3651 	gfp_t zero_flag;
3652 	int i = 0;
3653 
3654 	nents = DIV_ROUND_UP(length, PAGE_SIZE);
3655 	cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
3656 	if (!cmd->t_data_sg)
3657 		return -ENOMEM;
3658 
3659 	cmd->t_data_nents = nents;
3660 	sg_init_table(cmd->t_data_sg, nents);
3661 
3662 	zero_flag = cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB ? 0 : __GFP_ZERO;
3663 
3664 	while (length) {
3665 		u32 page_len = min_t(u32, length, PAGE_SIZE);
3666 		page = alloc_page(GFP_KERNEL | zero_flag);
3667 		if (!page)
3668 			goto out;
3669 
3670 		sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
3671 		length -= page_len;
3672 		i++;
3673 	}
3674 	return 0;
3675 
3676 out:
3677 	while (i >= 0) {
3678 		__free_page(sg_page(&cmd->t_data_sg[i]));
3679 		i--;
3680 	}
3681 	kfree(cmd->t_data_sg);
3682 	cmd->t_data_sg = NULL;
3683 	return -ENOMEM;
3684 }
3685 
3686 /* Reduce sectors if they are too long for the device */
3687 static inline sector_t transport_limit_task_sectors(
3688 	struct se_device *dev,
3689 	unsigned long long lba,
3690 	sector_t sectors)
3691 {
3692 	sectors = min_t(sector_t, sectors, dev->se_sub_dev->se_dev_attrib.max_sectors);
3693 
3694 	if (dev->transport->get_device_type(dev) == TYPE_DISK)
3695 		if ((lba + sectors) > transport_dev_end_lba(dev))
3696 			sectors = ((transport_dev_end_lba(dev) - lba) + 1);
3697 
3698 	return sectors;
3699 }
3700 
3701 
3702 /*
3703  * This function can be used by HW target mode drivers to create a linked
3704  * scatterlist from all contiguously allocated struct se_task->task_sg[].
3705  * This is intended to be called during the completion path by TCM Core
3706  * when struct target_core_fabric_ops->check_task_sg_chaining is enabled.
3707  */
3708 void transport_do_task_sg_chain(struct se_cmd *cmd)
3709 {
3710 	struct scatterlist *sg_first = NULL;
3711 	struct scatterlist *sg_prev = NULL;
3712 	int sg_prev_nents = 0;
3713 	struct scatterlist *sg;
3714 	struct se_task *task;
3715 	u32 chained_nents = 0;
3716 	int i;
3717 
3718 	BUG_ON(!cmd->se_tfo->task_sg_chaining);
3719 
3720 	/*
3721 	 * Walk the struct se_task list and setup scatterlist chains
3722 	 * for each contiguously allocated struct se_task->task_sg[].
3723 	 */
3724 	list_for_each_entry(task, &cmd->t_task_list, t_list) {
3725 		if (!task->task_sg)
3726 			continue;
3727 
3728 		if (!sg_first) {
3729 			sg_first = task->task_sg;
3730 			chained_nents = task->task_sg_nents;
3731 		} else {
3732 			sg_chain(sg_prev, sg_prev_nents, task->task_sg);
3733 			chained_nents += task->task_sg_nents;
3734 		}
3735 		/*
3736 		 * For the padded tasks, use the extra SGL vector allocated
3737 		 * in transport_allocate_data_tasks() for the sg_prev_nents
3738 		 * offset into sg_chain() above.
3739 		 *
3740 		 * We do not need the padding for the last task (or a single
3741 		 * task), but in that case we will never use the sg_prev_nents
3742 		 * value below which would be incorrect.
3743 		 */
3744 		sg_prev_nents = (task->task_sg_nents + 1);
3745 		sg_prev = task->task_sg;
3746 	}
3747 	/*
3748 	 * Setup the starting pointer and total t_tasks_sg_linked_no including
3749 	 * padding SGs for linking and to mark the end.
3750 	 */
3751 	cmd->t_tasks_sg_chained = sg_first;
3752 	cmd->t_tasks_sg_chained_no = chained_nents;
3753 
3754 	pr_debug("Setup cmd: %p cmd->t_tasks_sg_chained: %p and"
3755 		" t_tasks_sg_chained_no: %u\n", cmd, cmd->t_tasks_sg_chained,
3756 		cmd->t_tasks_sg_chained_no);
3757 
3758 	for_each_sg(cmd->t_tasks_sg_chained, sg,
3759 			cmd->t_tasks_sg_chained_no, i) {
3760 
3761 		pr_debug("SG[%d]: %p page: %p length: %d offset: %d\n",
3762 			i, sg, sg_page(sg), sg->length, sg->offset);
3763 		if (sg_is_chain(sg))
3764 			pr_debug("SG: %p sg_is_chain=1\n", sg);
3765 		if (sg_is_last(sg))
3766 			pr_debug("SG: %p sg_is_last=1\n", sg);
3767 	}
3768 }
3769 EXPORT_SYMBOL(transport_do_task_sg_chain);
3770 
3771 /*
3772  * Break up cmd into chunks transport can handle
3773  */
3774 static int
3775 transport_allocate_data_tasks(struct se_cmd *cmd,
3776 	enum dma_data_direction data_direction,
3777 	struct scatterlist *cmd_sg, unsigned int sgl_nents)
3778 {
3779 	struct se_device *dev = cmd->se_dev;
3780 	int task_count, i;
3781 	unsigned long long lba;
3782 	sector_t sectors, dev_max_sectors;
3783 	u32 sector_size;
3784 
3785 	if (transport_cmd_get_valid_sectors(cmd) < 0)
3786 		return -EINVAL;
3787 
3788 	dev_max_sectors = dev->se_sub_dev->se_dev_attrib.max_sectors;
3789 	sector_size = dev->se_sub_dev->se_dev_attrib.block_size;
3790 
3791 	WARN_ON(cmd->data_length % sector_size);
3792 
3793 	lba = cmd->t_task_lba;
3794 	sectors = DIV_ROUND_UP(cmd->data_length, sector_size);
3795 	task_count = DIV_ROUND_UP_SECTOR_T(sectors, dev_max_sectors);
3796 
3797 	/*
3798 	 * If we need just a single task reuse the SG list in the command
3799 	 * and avoid a lot of work.
3800 	 */
3801 	if (task_count == 1) {
3802 		struct se_task *task;
3803 		unsigned long flags;
3804 
3805 		task = transport_generic_get_task(cmd, data_direction);
3806 		if (!task)
3807 			return -ENOMEM;
3808 
3809 		task->task_sg = cmd_sg;
3810 		task->task_sg_nents = sgl_nents;
3811 
3812 		task->task_lba = lba;
3813 		task->task_sectors = sectors;
3814 		task->task_size = task->task_sectors * sector_size;
3815 
3816 		spin_lock_irqsave(&cmd->t_state_lock, flags);
3817 		list_add_tail(&task->t_list, &cmd->t_task_list);
3818 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3819 
3820 		return task_count;
3821 	}
3822 
3823 	for (i = 0; i < task_count; i++) {
3824 		struct se_task *task;
3825 		unsigned int task_size, task_sg_nents_padded;
3826 		struct scatterlist *sg;
3827 		unsigned long flags;
3828 		int count;
3829 
3830 		task = transport_generic_get_task(cmd, data_direction);
3831 		if (!task)
3832 			return -ENOMEM;
3833 
3834 		task->task_lba = lba;
3835 		task->task_sectors = min(sectors, dev_max_sectors);
3836 		task->task_size = task->task_sectors * sector_size;
3837 
3838 		/*
3839 		 * This now assumes that passed sg_ents are in PAGE_SIZE chunks
3840 		 * in order to calculate the number per task SGL entries
3841 		 */
3842 		task->task_sg_nents = DIV_ROUND_UP(task->task_size, PAGE_SIZE);
3843 		/*
3844 		 * Check if the fabric module driver is requesting that all
3845 		 * struct se_task->task_sg[] be chained together..  If so,
3846 		 * then allocate an extra padding SG entry for linking and
3847 		 * marking the end of the chained SGL for every task except
3848 		 * the last one for (task_count > 1) operation, or skipping
3849 		 * the extra padding for the (task_count == 1) case.
3850 		 */
3851 		if (cmd->se_tfo->task_sg_chaining && (i < (task_count - 1))) {
3852 			task_sg_nents_padded = (task->task_sg_nents + 1);
3853 		} else
3854 			task_sg_nents_padded = task->task_sg_nents;
3855 
3856 		task->task_sg = kmalloc(sizeof(struct scatterlist) *
3857 					task_sg_nents_padded, GFP_KERNEL);
3858 		if (!task->task_sg) {
3859 			cmd->se_dev->transport->free_task(task);
3860 			return -ENOMEM;
3861 		}
3862 
3863 		sg_init_table(task->task_sg, task_sg_nents_padded);
3864 
3865 		task_size = task->task_size;
3866 
3867 		/* Build new sgl, only up to task_size */
3868 		for_each_sg(task->task_sg, sg, task->task_sg_nents, count) {
3869 			if (cmd_sg->length > task_size)
3870 				break;
3871 
3872 			*sg = *cmd_sg;
3873 			task_size -= cmd_sg->length;
3874 			cmd_sg = sg_next(cmd_sg);
3875 		}
3876 
3877 		lba += task->task_sectors;
3878 		sectors -= task->task_sectors;
3879 
3880 		spin_lock_irqsave(&cmd->t_state_lock, flags);
3881 		list_add_tail(&task->t_list, &cmd->t_task_list);
3882 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3883 	}
3884 
3885 	return task_count;
3886 }
3887 
3888 static int
3889 transport_allocate_control_task(struct se_cmd *cmd)
3890 {
3891 	struct se_task *task;
3892 	unsigned long flags;
3893 
3894 	/* Workaround for handling zero-length control CDBs */
3895 	if ((cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) &&
3896 	    !cmd->data_length)
3897 		return 0;
3898 
3899 	task = transport_generic_get_task(cmd, cmd->data_direction);
3900 	if (!task)
3901 		return -ENOMEM;
3902 
3903 	task->task_sg = cmd->t_data_sg;
3904 	task->task_size = cmd->data_length;
3905 	task->task_sg_nents = cmd->t_data_nents;
3906 
3907 	spin_lock_irqsave(&cmd->t_state_lock, flags);
3908 	list_add_tail(&task->t_list, &cmd->t_task_list);
3909 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3910 
3911 	/* Success! Return number of tasks allocated */
3912 	return 1;
3913 }
3914 
3915 /*
3916  * Allocate any required ressources to execute the command, and either place
3917  * it on the execution queue if possible.  For writes we might not have the
3918  * payload yet, thus notify the fabric via a call to ->write_pending instead.
3919  */
3920 int transport_generic_new_cmd(struct se_cmd *cmd)
3921 {
3922 	struct se_device *dev = cmd->se_dev;
3923 	int task_cdbs, task_cdbs_bidi = 0;
3924 	int set_counts = 1;
3925 	int ret = 0;
3926 
3927 	/*
3928 	 * Determine is the TCM fabric module has already allocated physical
3929 	 * memory, and is directly calling transport_generic_map_mem_to_cmd()
3930 	 * beforehand.
3931 	 */
3932 	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
3933 	    cmd->data_length) {
3934 		ret = transport_generic_get_mem(cmd);
3935 		if (ret < 0)
3936 			goto out_fail;
3937 	}
3938 
3939 	/*
3940 	 * For BIDI command set up the read tasks first.
3941 	 */
3942 	if (cmd->t_bidi_data_sg &&
3943 	    dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) {
3944 		BUG_ON(!(cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB));
3945 
3946 		task_cdbs_bidi = transport_allocate_data_tasks(cmd,
3947 				DMA_FROM_DEVICE, cmd->t_bidi_data_sg,
3948 				cmd->t_bidi_data_nents);
3949 		if (task_cdbs_bidi <= 0)
3950 			goto out_fail;
3951 
3952 		atomic_inc(&cmd->t_fe_count);
3953 		atomic_inc(&cmd->t_se_count);
3954 		set_counts = 0;
3955 	}
3956 
3957 	if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
3958 		task_cdbs = transport_allocate_data_tasks(cmd,
3959 					cmd->data_direction, cmd->t_data_sg,
3960 					cmd->t_data_nents);
3961 	} else {
3962 		task_cdbs = transport_allocate_control_task(cmd);
3963 	}
3964 
3965 	if (task_cdbs < 0)
3966 		goto out_fail;
3967 	else if (!task_cdbs && (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)) {
3968 		spin_lock_irq(&cmd->t_state_lock);
3969 		cmd->t_state = TRANSPORT_COMPLETE;
3970 		cmd->transport_state |= CMD_T_ACTIVE;
3971 		spin_unlock_irq(&cmd->t_state_lock);
3972 
3973 		if (cmd->t_task_cdb[0] == REQUEST_SENSE) {
3974 			u8 ua_asc = 0, ua_ascq = 0;
3975 
3976 			core_scsi3_ua_clear_for_request_sense(cmd,
3977 					&ua_asc, &ua_ascq);
3978 		}
3979 
3980 		INIT_WORK(&cmd->work, target_complete_ok_work);
3981 		queue_work(target_completion_wq, &cmd->work);
3982 		return 0;
3983 	}
3984 
3985 	if (set_counts) {
3986 		atomic_inc(&cmd->t_fe_count);
3987 		atomic_inc(&cmd->t_se_count);
3988 	}
3989 
3990 	cmd->t_task_list_num = (task_cdbs + task_cdbs_bidi);
3991 	atomic_set(&cmd->t_task_cdbs_left, cmd->t_task_list_num);
3992 	atomic_set(&cmd->t_task_cdbs_ex_left, cmd->t_task_list_num);
3993 
3994 	/*
3995 	 * For WRITEs, let the fabric know its buffer is ready..
3996 	 * This WRITE struct se_cmd (and all of its associated struct se_task's)
3997 	 * will be added to the struct se_device execution queue after its WRITE
3998 	 * data has arrived. (ie: It gets handled by the transport processing
3999 	 * thread a second time)
4000 	 */
4001 	if (cmd->data_direction == DMA_TO_DEVICE) {
4002 		transport_add_tasks_to_state_queue(cmd);
4003 		return transport_generic_write_pending(cmd);
4004 	}
4005 	/*
4006 	 * Everything else but a WRITE, add the struct se_cmd's struct se_task's
4007 	 * to the execution queue.
4008 	 */
4009 	transport_execute_tasks(cmd);
4010 	return 0;
4011 
4012 out_fail:
4013 	cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
4014 	cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
4015 	return -EINVAL;
4016 }
4017 EXPORT_SYMBOL(transport_generic_new_cmd);
4018 
4019 /*	transport_generic_process_write():
4020  *
4021  *
4022  */
4023 void transport_generic_process_write(struct se_cmd *cmd)
4024 {
4025 	transport_execute_tasks(cmd);
4026 }
4027 EXPORT_SYMBOL(transport_generic_process_write);
4028 
4029 static void transport_write_pending_qf(struct se_cmd *cmd)
4030 {
4031 	int ret;
4032 
4033 	ret = cmd->se_tfo->write_pending(cmd);
4034 	if (ret == -EAGAIN || ret == -ENOMEM) {
4035 		pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
4036 			 cmd);
4037 		transport_handle_queue_full(cmd, cmd->se_dev);
4038 	}
4039 }
4040 
4041 static int transport_generic_write_pending(struct se_cmd *cmd)
4042 {
4043 	unsigned long flags;
4044 	int ret;
4045 
4046 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4047 	cmd->t_state = TRANSPORT_WRITE_PENDING;
4048 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4049 
4050 	/*
4051 	 * Clear the se_cmd for WRITE_PENDING status in order to set
4052 	 * CMD_T_ACTIVE so that transport_generic_handle_data can be called
4053 	 * from HW target mode interrupt code.  This is safe to be called
4054 	 * with transport_off=1 before the cmd->se_tfo->write_pending
4055 	 * because the se_cmd->se_lun pointer is not being cleared.
4056 	 */
4057 	transport_cmd_check_stop(cmd, 1, 0);
4058 
4059 	/*
4060 	 * Call the fabric write_pending function here to let the
4061 	 * frontend know that WRITE buffers are ready.
4062 	 */
4063 	ret = cmd->se_tfo->write_pending(cmd);
4064 	if (ret == -EAGAIN || ret == -ENOMEM)
4065 		goto queue_full;
4066 	else if (ret < 0)
4067 		return ret;
4068 
4069 	return 1;
4070 
4071 queue_full:
4072 	pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
4073 	cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
4074 	transport_handle_queue_full(cmd, cmd->se_dev);
4075 	return 0;
4076 }
4077 
4078 void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
4079 {
4080 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
4081 		if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
4082 			 transport_wait_for_tasks(cmd);
4083 
4084 		transport_release_cmd(cmd);
4085 	} else {
4086 		if (wait_for_tasks)
4087 			transport_wait_for_tasks(cmd);
4088 
4089 		core_dec_lacl_count(cmd->se_sess->se_node_acl, cmd);
4090 
4091 		if (cmd->se_lun)
4092 			transport_lun_remove_cmd(cmd);
4093 
4094 		transport_free_dev_tasks(cmd);
4095 
4096 		transport_put_cmd(cmd);
4097 	}
4098 }
4099 EXPORT_SYMBOL(transport_generic_free_cmd);
4100 
4101 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
4102  * @se_sess:	session to reference
4103  * @se_cmd:	command descriptor to add
4104  * @ack_kref:	Signal that fabric will perform an ack target_put_sess_cmd()
4105  */
4106 void target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
4107 			bool ack_kref)
4108 {
4109 	unsigned long flags;
4110 
4111 	kref_init(&se_cmd->cmd_kref);
4112 	/*
4113 	 * Add a second kref if the fabric caller is expecting to handle
4114 	 * fabric acknowledgement that requires two target_put_sess_cmd()
4115 	 * invocations before se_cmd descriptor release.
4116 	 */
4117 	if (ack_kref == true) {
4118 		kref_get(&se_cmd->cmd_kref);
4119 		se_cmd->se_cmd_flags |= SCF_ACK_KREF;
4120 	}
4121 
4122 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
4123 	list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
4124 	se_cmd->check_release = 1;
4125 	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
4126 }
4127 EXPORT_SYMBOL(target_get_sess_cmd);
4128 
4129 static void target_release_cmd_kref(struct kref *kref)
4130 {
4131 	struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
4132 	struct se_session *se_sess = se_cmd->se_sess;
4133 	unsigned long flags;
4134 
4135 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
4136 	if (list_empty(&se_cmd->se_cmd_list)) {
4137 		spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
4138 		se_cmd->se_tfo->release_cmd(se_cmd);
4139 		return;
4140 	}
4141 	if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
4142 		spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
4143 		complete(&se_cmd->cmd_wait_comp);
4144 		return;
4145 	}
4146 	list_del(&se_cmd->se_cmd_list);
4147 	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
4148 
4149 	se_cmd->se_tfo->release_cmd(se_cmd);
4150 }
4151 
4152 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
4153  * @se_sess:	session to reference
4154  * @se_cmd:	command descriptor to drop
4155  */
4156 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
4157 {
4158 	return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
4159 }
4160 EXPORT_SYMBOL(target_put_sess_cmd);
4161 
4162 /* target_splice_sess_cmd_list - Split active cmds into sess_wait_list
4163  * @se_sess:	session to split
4164  */
4165 void target_splice_sess_cmd_list(struct se_session *se_sess)
4166 {
4167 	struct se_cmd *se_cmd;
4168 	unsigned long flags;
4169 
4170 	WARN_ON(!list_empty(&se_sess->sess_wait_list));
4171 	INIT_LIST_HEAD(&se_sess->sess_wait_list);
4172 
4173 	spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
4174 	se_sess->sess_tearing_down = 1;
4175 
4176 	list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
4177 
4178 	list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
4179 		se_cmd->cmd_wait_set = 1;
4180 
4181 	spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
4182 }
4183 EXPORT_SYMBOL(target_splice_sess_cmd_list);
4184 
4185 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
4186  * @se_sess:    session to wait for active I/O
4187  * @wait_for_tasks:	Make extra transport_wait_for_tasks call
4188  */
4189 void target_wait_for_sess_cmds(
4190 	struct se_session *se_sess,
4191 	int wait_for_tasks)
4192 {
4193 	struct se_cmd *se_cmd, *tmp_cmd;
4194 	bool rc = false;
4195 
4196 	list_for_each_entry_safe(se_cmd, tmp_cmd,
4197 				&se_sess->sess_wait_list, se_cmd_list) {
4198 		list_del(&se_cmd->se_cmd_list);
4199 
4200 		pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
4201 			" %d\n", se_cmd, se_cmd->t_state,
4202 			se_cmd->se_tfo->get_cmd_state(se_cmd));
4203 
4204 		if (wait_for_tasks) {
4205 			pr_debug("Calling transport_wait_for_tasks se_cmd: %p t_state: %d,"
4206 				" fabric state: %d\n", se_cmd, se_cmd->t_state,
4207 				se_cmd->se_tfo->get_cmd_state(se_cmd));
4208 
4209 			rc = transport_wait_for_tasks(se_cmd);
4210 
4211 			pr_debug("After transport_wait_for_tasks se_cmd: %p t_state: %d,"
4212 				" fabric state: %d\n", se_cmd, se_cmd->t_state,
4213 				se_cmd->se_tfo->get_cmd_state(se_cmd));
4214 		}
4215 
4216 		if (!rc) {
4217 			wait_for_completion(&se_cmd->cmd_wait_comp);
4218 			pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
4219 				" fabric state: %d\n", se_cmd, se_cmd->t_state,
4220 				se_cmd->se_tfo->get_cmd_state(se_cmd));
4221 		}
4222 
4223 		se_cmd->se_tfo->release_cmd(se_cmd);
4224 	}
4225 }
4226 EXPORT_SYMBOL(target_wait_for_sess_cmds);
4227 
4228 /*	transport_lun_wait_for_tasks():
4229  *
4230  *	Called from ConfigFS context to stop the passed struct se_cmd to allow
4231  *	an struct se_lun to be successfully shutdown.
4232  */
4233 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
4234 {
4235 	unsigned long flags;
4236 	int ret;
4237 	/*
4238 	 * If the frontend has already requested this struct se_cmd to
4239 	 * be stopped, we can safely ignore this struct se_cmd.
4240 	 */
4241 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4242 	if (cmd->transport_state & CMD_T_STOP) {
4243 		cmd->transport_state &= ~CMD_T_LUN_STOP;
4244 
4245 		pr_debug("ConfigFS ITT[0x%08x] - CMD_T_STOP, skipping\n",
4246 			 cmd->se_tfo->get_task_tag(cmd));
4247 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4248 		transport_cmd_check_stop(cmd, 1, 0);
4249 		return -EPERM;
4250 	}
4251 	cmd->transport_state |= CMD_T_LUN_FE_STOP;
4252 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4253 
4254 	wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
4255 
4256 	ret = transport_stop_tasks_for_cmd(cmd);
4257 
4258 	pr_debug("ConfigFS: cmd: %p t_tasks: %d stop tasks ret:"
4259 			" %d\n", cmd, cmd->t_task_list_num, ret);
4260 	if (!ret) {
4261 		pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
4262 				cmd->se_tfo->get_task_tag(cmd));
4263 		wait_for_completion(&cmd->transport_lun_stop_comp);
4264 		pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
4265 				cmd->se_tfo->get_task_tag(cmd));
4266 	}
4267 	transport_remove_cmd_from_queue(cmd);
4268 
4269 	return 0;
4270 }
4271 
4272 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
4273 {
4274 	struct se_cmd *cmd = NULL;
4275 	unsigned long lun_flags, cmd_flags;
4276 	/*
4277 	 * Do exception processing and return CHECK_CONDITION status to the
4278 	 * Initiator Port.
4279 	 */
4280 	spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4281 	while (!list_empty(&lun->lun_cmd_list)) {
4282 		cmd = list_first_entry(&lun->lun_cmd_list,
4283 		       struct se_cmd, se_lun_node);
4284 		list_del_init(&cmd->se_lun_node);
4285 
4286 		/*
4287 		 * This will notify iscsi_target_transport.c:
4288 		 * transport_cmd_check_stop() that a LUN shutdown is in
4289 		 * progress for the iscsi_cmd_t.
4290 		 */
4291 		spin_lock(&cmd->t_state_lock);
4292 		pr_debug("SE_LUN[%d] - Setting cmd->transport"
4293 			"_lun_stop for  ITT: 0x%08x\n",
4294 			cmd->se_lun->unpacked_lun,
4295 			cmd->se_tfo->get_task_tag(cmd));
4296 		cmd->transport_state |= CMD_T_LUN_STOP;
4297 		spin_unlock(&cmd->t_state_lock);
4298 
4299 		spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
4300 
4301 		if (!cmd->se_lun) {
4302 			pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
4303 				cmd->se_tfo->get_task_tag(cmd),
4304 				cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
4305 			BUG();
4306 		}
4307 		/*
4308 		 * If the Storage engine still owns the iscsi_cmd_t, determine
4309 		 * and/or stop its context.
4310 		 */
4311 		pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
4312 			"_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
4313 			cmd->se_tfo->get_task_tag(cmd));
4314 
4315 		if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
4316 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4317 			continue;
4318 		}
4319 
4320 		pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
4321 			"_wait_for_tasks(): SUCCESS\n",
4322 			cmd->se_lun->unpacked_lun,
4323 			cmd->se_tfo->get_task_tag(cmd));
4324 
4325 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
4326 		if (!(cmd->transport_state & CMD_T_DEV_ACTIVE)) {
4327 			spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4328 			goto check_cond;
4329 		}
4330 		cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
4331 		transport_all_task_dev_remove_state(cmd);
4332 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4333 
4334 		transport_free_dev_tasks(cmd);
4335 		/*
4336 		 * The Storage engine stopped this struct se_cmd before it was
4337 		 * send to the fabric frontend for delivery back to the
4338 		 * Initiator Node.  Return this SCSI CDB back with an
4339 		 * CHECK_CONDITION status.
4340 		 */
4341 check_cond:
4342 		transport_send_check_condition_and_sense(cmd,
4343 				TCM_NON_EXISTENT_LUN, 0);
4344 		/*
4345 		 *  If the fabric frontend is waiting for this iscsi_cmd_t to
4346 		 * be released, notify the waiting thread now that LU has
4347 		 * finished accessing it.
4348 		 */
4349 		spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
4350 		if (cmd->transport_state & CMD_T_LUN_FE_STOP) {
4351 			pr_debug("SE_LUN[%d] - Detected FE stop for"
4352 				" struct se_cmd: %p ITT: 0x%08x\n",
4353 				lun->unpacked_lun,
4354 				cmd, cmd->se_tfo->get_task_tag(cmd));
4355 
4356 			spin_unlock_irqrestore(&cmd->t_state_lock,
4357 					cmd_flags);
4358 			transport_cmd_check_stop(cmd, 1, 0);
4359 			complete(&cmd->transport_lun_fe_stop_comp);
4360 			spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4361 			continue;
4362 		}
4363 		pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
4364 			lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
4365 
4366 		spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4367 		spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4368 	}
4369 	spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
4370 }
4371 
4372 static int transport_clear_lun_thread(void *p)
4373 {
4374 	struct se_lun *lun = p;
4375 
4376 	__transport_clear_lun_from_sessions(lun);
4377 	complete(&lun->lun_shutdown_comp);
4378 
4379 	return 0;
4380 }
4381 
4382 int transport_clear_lun_from_sessions(struct se_lun *lun)
4383 {
4384 	struct task_struct *kt;
4385 
4386 	kt = kthread_run(transport_clear_lun_thread, lun,
4387 			"tcm_cl_%u", lun->unpacked_lun);
4388 	if (IS_ERR(kt)) {
4389 		pr_err("Unable to start clear_lun thread\n");
4390 		return PTR_ERR(kt);
4391 	}
4392 	wait_for_completion(&lun->lun_shutdown_comp);
4393 
4394 	return 0;
4395 }
4396 
4397 /**
4398  * transport_wait_for_tasks - wait for completion to occur
4399  * @cmd:	command to wait
4400  *
4401  * Called from frontend fabric context to wait for storage engine
4402  * to pause and/or release frontend generated struct se_cmd.
4403  */
4404 bool transport_wait_for_tasks(struct se_cmd *cmd)
4405 {
4406 	unsigned long flags;
4407 
4408 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4409 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
4410 	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
4411 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4412 		return false;
4413 	}
4414 	/*
4415 	 * Only perform a possible wait_for_tasks if SCF_SUPPORTED_SAM_OPCODE
4416 	 * has been set in transport_set_supported_SAM_opcode().
4417 	 */
4418 	if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
4419 	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
4420 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4421 		return false;
4422 	}
4423 	/*
4424 	 * If we are already stopped due to an external event (ie: LUN shutdown)
4425 	 * sleep until the connection can have the passed struct se_cmd back.
4426 	 * The cmd->transport_lun_stopped_sem will be upped by
4427 	 * transport_clear_lun_from_sessions() once the ConfigFS context caller
4428 	 * has completed its operation on the struct se_cmd.
4429 	 */
4430 	if (cmd->transport_state & CMD_T_LUN_STOP) {
4431 		pr_debug("wait_for_tasks: Stopping"
4432 			" wait_for_completion(&cmd->t_tasktransport_lun_fe"
4433 			"_stop_comp); for ITT: 0x%08x\n",
4434 			cmd->se_tfo->get_task_tag(cmd));
4435 		/*
4436 		 * There is a special case for WRITES where a FE exception +
4437 		 * LUN shutdown means ConfigFS context is still sleeping on
4438 		 * transport_lun_stop_comp in transport_lun_wait_for_tasks().
4439 		 * We go ahead and up transport_lun_stop_comp just to be sure
4440 		 * here.
4441 		 */
4442 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4443 		complete(&cmd->transport_lun_stop_comp);
4444 		wait_for_completion(&cmd->transport_lun_fe_stop_comp);
4445 		spin_lock_irqsave(&cmd->t_state_lock, flags);
4446 
4447 		transport_all_task_dev_remove_state(cmd);
4448 		/*
4449 		 * At this point, the frontend who was the originator of this
4450 		 * struct se_cmd, now owns the structure and can be released through
4451 		 * normal means below.
4452 		 */
4453 		pr_debug("wait_for_tasks: Stopped"
4454 			" wait_for_completion(&cmd->t_tasktransport_lun_fe_"
4455 			"stop_comp); for ITT: 0x%08x\n",
4456 			cmd->se_tfo->get_task_tag(cmd));
4457 
4458 		cmd->transport_state &= ~CMD_T_LUN_STOP;
4459 	}
4460 
4461 	if (!(cmd->transport_state & CMD_T_ACTIVE)) {
4462 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4463 		return false;
4464 	}
4465 
4466 	cmd->transport_state |= CMD_T_STOP;
4467 
4468 	pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
4469 		" i_state: %d, t_state: %d, CMD_T_STOP\n",
4470 		cmd, cmd->se_tfo->get_task_tag(cmd),
4471 		cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
4472 
4473 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4474 
4475 	wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
4476 
4477 	wait_for_completion(&cmd->t_transport_stop_comp);
4478 
4479 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4480 	cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
4481 
4482 	pr_debug("wait_for_tasks: Stopped wait_for_compltion("
4483 		"&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
4484 		cmd->se_tfo->get_task_tag(cmd));
4485 
4486 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4487 
4488 	return true;
4489 }
4490 EXPORT_SYMBOL(transport_wait_for_tasks);
4491 
4492 static int transport_get_sense_codes(
4493 	struct se_cmd *cmd,
4494 	u8 *asc,
4495 	u8 *ascq)
4496 {
4497 	*asc = cmd->scsi_asc;
4498 	*ascq = cmd->scsi_ascq;
4499 
4500 	return 0;
4501 }
4502 
4503 static int transport_set_sense_codes(
4504 	struct se_cmd *cmd,
4505 	u8 asc,
4506 	u8 ascq)
4507 {
4508 	cmd->scsi_asc = asc;
4509 	cmd->scsi_ascq = ascq;
4510 
4511 	return 0;
4512 }
4513 
4514 int transport_send_check_condition_and_sense(
4515 	struct se_cmd *cmd,
4516 	u8 reason,
4517 	int from_transport)
4518 {
4519 	unsigned char *buffer = cmd->sense_buffer;
4520 	unsigned long flags;
4521 	int offset;
4522 	u8 asc = 0, ascq = 0;
4523 
4524 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4525 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
4526 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4527 		return 0;
4528 	}
4529 	cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
4530 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4531 
4532 	if (!reason && from_transport)
4533 		goto after_reason;
4534 
4535 	if (!from_transport)
4536 		cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
4537 	/*
4538 	 * Data Segment and SenseLength of the fabric response PDU.
4539 	 *
4540 	 * TRANSPORT_SENSE_BUFFER is now set to SCSI_SENSE_BUFFERSIZE
4541 	 * from include/scsi/scsi_cmnd.h
4542 	 */
4543 	offset = cmd->se_tfo->set_fabric_sense_len(cmd,
4544 				TRANSPORT_SENSE_BUFFER);
4545 	/*
4546 	 * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
4547 	 * SENSE KEY values from include/scsi/scsi.h
4548 	 */
4549 	switch (reason) {
4550 	case TCM_NON_EXISTENT_LUN:
4551 		/* CURRENT ERROR */
4552 		buffer[offset] = 0x70;
4553 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4554 		/* ILLEGAL REQUEST */
4555 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4556 		/* LOGICAL UNIT NOT SUPPORTED */
4557 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x25;
4558 		break;
4559 	case TCM_UNSUPPORTED_SCSI_OPCODE:
4560 	case TCM_SECTOR_COUNT_TOO_MANY:
4561 		/* CURRENT ERROR */
4562 		buffer[offset] = 0x70;
4563 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4564 		/* ILLEGAL REQUEST */
4565 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4566 		/* INVALID COMMAND OPERATION CODE */
4567 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x20;
4568 		break;
4569 	case TCM_UNKNOWN_MODE_PAGE:
4570 		/* CURRENT ERROR */
4571 		buffer[offset] = 0x70;
4572 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4573 		/* ILLEGAL REQUEST */
4574 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4575 		/* INVALID FIELD IN CDB */
4576 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
4577 		break;
4578 	case TCM_CHECK_CONDITION_ABORT_CMD:
4579 		/* CURRENT ERROR */
4580 		buffer[offset] = 0x70;
4581 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4582 		/* ABORTED COMMAND */
4583 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4584 		/* BUS DEVICE RESET FUNCTION OCCURRED */
4585 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x29;
4586 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x03;
4587 		break;
4588 	case TCM_INCORRECT_AMOUNT_OF_DATA:
4589 		/* CURRENT ERROR */
4590 		buffer[offset] = 0x70;
4591 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4592 		/* ABORTED COMMAND */
4593 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4594 		/* WRITE ERROR */
4595 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x0c;
4596 		/* NOT ENOUGH UNSOLICITED DATA */
4597 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0d;
4598 		break;
4599 	case TCM_INVALID_CDB_FIELD:
4600 		/* CURRENT ERROR */
4601 		buffer[offset] = 0x70;
4602 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4603 		/* ILLEGAL REQUEST */
4604 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4605 		/* INVALID FIELD IN CDB */
4606 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
4607 		break;
4608 	case TCM_INVALID_PARAMETER_LIST:
4609 		/* CURRENT ERROR */
4610 		buffer[offset] = 0x70;
4611 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4612 		/* ILLEGAL REQUEST */
4613 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4614 		/* INVALID FIELD IN PARAMETER LIST */
4615 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x26;
4616 		break;
4617 	case TCM_UNEXPECTED_UNSOLICITED_DATA:
4618 		/* CURRENT ERROR */
4619 		buffer[offset] = 0x70;
4620 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4621 		/* ABORTED COMMAND */
4622 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4623 		/* WRITE ERROR */
4624 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x0c;
4625 		/* UNEXPECTED_UNSOLICITED_DATA */
4626 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0c;
4627 		break;
4628 	case TCM_SERVICE_CRC_ERROR:
4629 		/* CURRENT ERROR */
4630 		buffer[offset] = 0x70;
4631 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4632 		/* ABORTED COMMAND */
4633 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4634 		/* PROTOCOL SERVICE CRC ERROR */
4635 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x47;
4636 		/* N/A */
4637 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x05;
4638 		break;
4639 	case TCM_SNACK_REJECTED:
4640 		/* CURRENT ERROR */
4641 		buffer[offset] = 0x70;
4642 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4643 		/* ABORTED COMMAND */
4644 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4645 		/* READ ERROR */
4646 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x11;
4647 		/* FAILED RETRANSMISSION REQUEST */
4648 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x13;
4649 		break;
4650 	case TCM_WRITE_PROTECTED:
4651 		/* CURRENT ERROR */
4652 		buffer[offset] = 0x70;
4653 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4654 		/* DATA PROTECT */
4655 		buffer[offset+SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
4656 		/* WRITE PROTECTED */
4657 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x27;
4658 		break;
4659 	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
4660 		/* CURRENT ERROR */
4661 		buffer[offset] = 0x70;
4662 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4663 		/* UNIT ATTENTION */
4664 		buffer[offset+SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
4665 		core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
4666 		buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
4667 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
4668 		break;
4669 	case TCM_CHECK_CONDITION_NOT_READY:
4670 		/* CURRENT ERROR */
4671 		buffer[offset] = 0x70;
4672 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4673 		/* Not Ready */
4674 		buffer[offset+SPC_SENSE_KEY_OFFSET] = NOT_READY;
4675 		transport_get_sense_codes(cmd, &asc, &ascq);
4676 		buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
4677 		buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
4678 		break;
4679 	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
4680 	default:
4681 		/* CURRENT ERROR */
4682 		buffer[offset] = 0x70;
4683 		buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10;
4684 		/* ILLEGAL REQUEST */
4685 		buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4686 		/* LOGICAL UNIT COMMUNICATION FAILURE */
4687 		buffer[offset+SPC_ASC_KEY_OFFSET] = 0x80;
4688 		break;
4689 	}
4690 	/*
4691 	 * This code uses linux/include/scsi/scsi.h SAM status codes!
4692 	 */
4693 	cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
4694 	/*
4695 	 * Automatically padded, this value is encoded in the fabric's
4696 	 * data_length response PDU containing the SCSI defined sense data.
4697 	 */
4698 	cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER + offset;
4699 
4700 after_reason:
4701 	return cmd->se_tfo->queue_status(cmd);
4702 }
4703 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
4704 
4705 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
4706 {
4707 	int ret = 0;
4708 
4709 	if (cmd->transport_state & CMD_T_ABORTED) {
4710 		if (!send_status ||
4711 		     (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
4712 			return 1;
4713 #if 0
4714 		pr_debug("Sending delayed SAM_STAT_TASK_ABORTED"
4715 			" status for CDB: 0x%02x ITT: 0x%08x\n",
4716 			cmd->t_task_cdb[0],
4717 			cmd->se_tfo->get_task_tag(cmd));
4718 #endif
4719 		cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
4720 		cmd->se_tfo->queue_status(cmd);
4721 		ret = 1;
4722 	}
4723 	return ret;
4724 }
4725 EXPORT_SYMBOL(transport_check_aborted_status);
4726 
4727 void transport_send_task_abort(struct se_cmd *cmd)
4728 {
4729 	unsigned long flags;
4730 
4731 	spin_lock_irqsave(&cmd->t_state_lock, flags);
4732 	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
4733 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4734 		return;
4735 	}
4736 	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4737 
4738 	/*
4739 	 * If there are still expected incoming fabric WRITEs, we wait
4740 	 * until until they have completed before sending a TASK_ABORTED
4741 	 * response.  This response with TASK_ABORTED status will be
4742 	 * queued back to fabric module by transport_check_aborted_status().
4743 	 */
4744 	if (cmd->data_direction == DMA_TO_DEVICE) {
4745 		if (cmd->se_tfo->write_pending_status(cmd) != 0) {
4746 			cmd->transport_state |= CMD_T_ABORTED;
4747 			smp_mb__after_atomic_inc();
4748 		}
4749 	}
4750 	cmd->scsi_status = SAM_STAT_TASK_ABORTED;
4751 #if 0
4752 	pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
4753 		" ITT: 0x%08x\n", cmd->t_task_cdb[0],
4754 		cmd->se_tfo->get_task_tag(cmd));
4755 #endif
4756 	cmd->se_tfo->queue_status(cmd);
4757 }
4758 
4759 static int transport_generic_do_tmr(struct se_cmd *cmd)
4760 {
4761 	struct se_device *dev = cmd->se_dev;
4762 	struct se_tmr_req *tmr = cmd->se_tmr_req;
4763 	int ret;
4764 
4765 	switch (tmr->function) {
4766 	case TMR_ABORT_TASK:
4767 		core_tmr_abort_task(dev, tmr, cmd->se_sess);
4768 		break;
4769 	case TMR_ABORT_TASK_SET:
4770 	case TMR_CLEAR_ACA:
4771 	case TMR_CLEAR_TASK_SET:
4772 		tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
4773 		break;
4774 	case TMR_LUN_RESET:
4775 		ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
4776 		tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
4777 					 TMR_FUNCTION_REJECTED;
4778 		break;
4779 	case TMR_TARGET_WARM_RESET:
4780 		tmr->response = TMR_FUNCTION_REJECTED;
4781 		break;
4782 	case TMR_TARGET_COLD_RESET:
4783 		tmr->response = TMR_FUNCTION_REJECTED;
4784 		break;
4785 	default:
4786 		pr_err("Uknown TMR function: 0x%02x.\n",
4787 				tmr->function);
4788 		tmr->response = TMR_FUNCTION_REJECTED;
4789 		break;
4790 	}
4791 
4792 	cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
4793 	cmd->se_tfo->queue_tm_rsp(cmd);
4794 
4795 	transport_cmd_check_stop_to_fabric(cmd);
4796 	return 0;
4797 }
4798 
4799 /*	transport_processing_thread():
4800  *
4801  *
4802  */
4803 static int transport_processing_thread(void *param)
4804 {
4805 	int ret;
4806 	struct se_cmd *cmd;
4807 	struct se_device *dev = param;
4808 
4809 	while (!kthread_should_stop()) {
4810 		ret = wait_event_interruptible(dev->dev_queue_obj.thread_wq,
4811 				atomic_read(&dev->dev_queue_obj.queue_cnt) ||
4812 				kthread_should_stop());
4813 		if (ret < 0)
4814 			goto out;
4815 
4816 get_cmd:
4817 		cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj);
4818 		if (!cmd)
4819 			continue;
4820 
4821 		switch (cmd->t_state) {
4822 		case TRANSPORT_NEW_CMD:
4823 			BUG();
4824 			break;
4825 		case TRANSPORT_NEW_CMD_MAP:
4826 			if (!cmd->se_tfo->new_cmd_map) {
4827 				pr_err("cmd->se_tfo->new_cmd_map is"
4828 					" NULL for TRANSPORT_NEW_CMD_MAP\n");
4829 				BUG();
4830 			}
4831 			ret = cmd->se_tfo->new_cmd_map(cmd);
4832 			if (ret < 0) {
4833 				transport_generic_request_failure(cmd);
4834 				break;
4835 			}
4836 			ret = transport_generic_new_cmd(cmd);
4837 			if (ret < 0) {
4838 				transport_generic_request_failure(cmd);
4839 				break;
4840 			}
4841 			break;
4842 		case TRANSPORT_PROCESS_WRITE:
4843 			transport_generic_process_write(cmd);
4844 			break;
4845 		case TRANSPORT_PROCESS_TMR:
4846 			transport_generic_do_tmr(cmd);
4847 			break;
4848 		case TRANSPORT_COMPLETE_QF_WP:
4849 			transport_write_pending_qf(cmd);
4850 			break;
4851 		case TRANSPORT_COMPLETE_QF_OK:
4852 			transport_complete_qf(cmd);
4853 			break;
4854 		default:
4855 			pr_err("Unknown t_state: %d  for ITT: 0x%08x "
4856 				"i_state: %d on SE LUN: %u\n",
4857 				cmd->t_state,
4858 				cmd->se_tfo->get_task_tag(cmd),
4859 				cmd->se_tfo->get_cmd_state(cmd),
4860 				cmd->se_lun->unpacked_lun);
4861 			BUG();
4862 		}
4863 
4864 		goto get_cmd;
4865 	}
4866 
4867 out:
4868 	WARN_ON(!list_empty(&dev->state_task_list));
4869 	WARN_ON(!list_empty(&dev->dev_queue_obj.qobj_list));
4870 	dev->process_thread = NULL;
4871 	return 0;
4872 }
4873