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Merge tag 'mac80211-for-davem-2015-10-13' of git://git.kernel.org/pub/scm/linux/kerne...
[mirror_ubuntu-artful-kernel.git] / drivers / target / target_core_transport.c
1 /*******************************************************************************
2 * Filename: target_core_transport.c
3 *
4 * This file contains the Generic Target Engine Core.
5 *
6 * (c) Copyright 2002-2013 Datera, Inc.
7 *
8 * Nicholas A. Bellinger <nab@kernel.org>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 *
24 ******************************************************************************/
25
26 #include <linux/net.h>
27 #include <linux/delay.h>
28 #include <linux/string.h>
29 #include <linux/timer.h>
30 #include <linux/slab.h>
31 #include <linux/spinlock.h>
32 #include <linux/kthread.h>
33 #include <linux/in.h>
34 #include <linux/cdrom.h>
35 #include <linux/module.h>
36 #include <linux/ratelimit.h>
37 #include <linux/vmalloc.h>
38 #include <asm/unaligned.h>
39 #include <net/sock.h>
40 #include <net/tcp.h>
41 #include <scsi/scsi_proto.h>
42 #include <scsi/scsi_common.h>
43
44 #include <target/target_core_base.h>
45 #include <target/target_core_backend.h>
46 #include <target/target_core_fabric.h>
47
48 #include "target_core_internal.h"
49 #include "target_core_alua.h"
50 #include "target_core_pr.h"
51 #include "target_core_ua.h"
52
53 #define CREATE_TRACE_POINTS
54 #include <trace/events/target.h>
55
56 static struct workqueue_struct *target_completion_wq;
57 static struct kmem_cache *se_sess_cache;
58 struct kmem_cache *se_ua_cache;
59 struct kmem_cache *t10_pr_reg_cache;
60 struct kmem_cache *t10_alua_lu_gp_cache;
61 struct kmem_cache *t10_alua_lu_gp_mem_cache;
62 struct kmem_cache *t10_alua_tg_pt_gp_cache;
63 struct kmem_cache *t10_alua_lba_map_cache;
64 struct kmem_cache *t10_alua_lba_map_mem_cache;
65
66 static void transport_complete_task_attr(struct se_cmd *cmd);
67 static void transport_handle_queue_full(struct se_cmd *cmd,
68 struct se_device *dev);
69 static int transport_put_cmd(struct se_cmd *cmd);
70 static void target_complete_ok_work(struct work_struct *work);
71
72 int init_se_kmem_caches(void)
73 {
74 se_sess_cache = kmem_cache_create("se_sess_cache",
75 sizeof(struct se_session), __alignof__(struct se_session),
76 0, NULL);
77 if (!se_sess_cache) {
78 pr_err("kmem_cache_create() for struct se_session"
79 " failed\n");
80 goto out;
81 }
82 se_ua_cache = kmem_cache_create("se_ua_cache",
83 sizeof(struct se_ua), __alignof__(struct se_ua),
84 0, NULL);
85 if (!se_ua_cache) {
86 pr_err("kmem_cache_create() for struct se_ua failed\n");
87 goto out_free_sess_cache;
88 }
89 t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
90 sizeof(struct t10_pr_registration),
91 __alignof__(struct t10_pr_registration), 0, NULL);
92 if (!t10_pr_reg_cache) {
93 pr_err("kmem_cache_create() for struct t10_pr_registration"
94 " failed\n");
95 goto out_free_ua_cache;
96 }
97 t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
98 sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
99 0, NULL);
100 if (!t10_alua_lu_gp_cache) {
101 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
102 " failed\n");
103 goto out_free_pr_reg_cache;
104 }
105 t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
106 sizeof(struct t10_alua_lu_gp_member),
107 __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
108 if (!t10_alua_lu_gp_mem_cache) {
109 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
110 "cache failed\n");
111 goto out_free_lu_gp_cache;
112 }
113 t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
114 sizeof(struct t10_alua_tg_pt_gp),
115 __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
116 if (!t10_alua_tg_pt_gp_cache) {
117 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
118 "cache failed\n");
119 goto out_free_lu_gp_mem_cache;
120 }
121 t10_alua_lba_map_cache = kmem_cache_create(
122 "t10_alua_lba_map_cache",
123 sizeof(struct t10_alua_lba_map),
124 __alignof__(struct t10_alua_lba_map), 0, NULL);
125 if (!t10_alua_lba_map_cache) {
126 pr_err("kmem_cache_create() for t10_alua_lba_map_"
127 "cache failed\n");
128 goto out_free_tg_pt_gp_cache;
129 }
130 t10_alua_lba_map_mem_cache = kmem_cache_create(
131 "t10_alua_lba_map_mem_cache",
132 sizeof(struct t10_alua_lba_map_member),
133 __alignof__(struct t10_alua_lba_map_member), 0, NULL);
134 if (!t10_alua_lba_map_mem_cache) {
135 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
136 "cache failed\n");
137 goto out_free_lba_map_cache;
138 }
139
140 target_completion_wq = alloc_workqueue("target_completion",
141 WQ_MEM_RECLAIM, 0);
142 if (!target_completion_wq)
143 goto out_free_lba_map_mem_cache;
144
145 return 0;
146
147 out_free_lba_map_mem_cache:
148 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
149 out_free_lba_map_cache:
150 kmem_cache_destroy(t10_alua_lba_map_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_lba_map_cache);
177 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
178 }
179
180 /* This code ensures unique mib indexes are handed out. */
181 static DEFINE_SPINLOCK(scsi_mib_index_lock);
182 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
183
184 /*
185 * Allocate a new row index for the entry type specified
186 */
187 u32 scsi_get_new_index(scsi_index_t type)
188 {
189 u32 new_index;
190
191 BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
192
193 spin_lock(&scsi_mib_index_lock);
194 new_index = ++scsi_mib_index[type];
195 spin_unlock(&scsi_mib_index_lock);
196
197 return new_index;
198 }
199
200 void transport_subsystem_check_init(void)
201 {
202 int ret;
203 static int sub_api_initialized;
204
205 if (sub_api_initialized)
206 return;
207
208 ret = request_module("target_core_iblock");
209 if (ret != 0)
210 pr_err("Unable to load target_core_iblock\n");
211
212 ret = request_module("target_core_file");
213 if (ret != 0)
214 pr_err("Unable to load target_core_file\n");
215
216 ret = request_module("target_core_pscsi");
217 if (ret != 0)
218 pr_err("Unable to load target_core_pscsi\n");
219
220 ret = request_module("target_core_user");
221 if (ret != 0)
222 pr_err("Unable to load target_core_user\n");
223
224 sub_api_initialized = 1;
225 }
226
227 struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
228 {
229 struct se_session *se_sess;
230
231 se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
232 if (!se_sess) {
233 pr_err("Unable to allocate struct se_session from"
234 " se_sess_cache\n");
235 return ERR_PTR(-ENOMEM);
236 }
237 INIT_LIST_HEAD(&se_sess->sess_list);
238 INIT_LIST_HEAD(&se_sess->sess_acl_list);
239 INIT_LIST_HEAD(&se_sess->sess_cmd_list);
240 INIT_LIST_HEAD(&se_sess->sess_wait_list);
241 spin_lock_init(&se_sess->sess_cmd_lock);
242 kref_init(&se_sess->sess_kref);
243 se_sess->sup_prot_ops = sup_prot_ops;
244
245 return se_sess;
246 }
247 EXPORT_SYMBOL(transport_init_session);
248
249 int transport_alloc_session_tags(struct se_session *se_sess,
250 unsigned int tag_num, unsigned int tag_size)
251 {
252 int rc;
253
254 se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
255 GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
256 if (!se_sess->sess_cmd_map) {
257 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
258 if (!se_sess->sess_cmd_map) {
259 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
260 return -ENOMEM;
261 }
262 }
263
264 rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
265 if (rc < 0) {
266 pr_err("Unable to init se_sess->sess_tag_pool,"
267 " tag_num: %u\n", tag_num);
268 kvfree(se_sess->sess_cmd_map);
269 se_sess->sess_cmd_map = NULL;
270 return -ENOMEM;
271 }
272
273 return 0;
274 }
275 EXPORT_SYMBOL(transport_alloc_session_tags);
276
277 struct se_session *transport_init_session_tags(unsigned int tag_num,
278 unsigned int tag_size,
279 enum target_prot_op sup_prot_ops)
280 {
281 struct se_session *se_sess;
282 int rc;
283
284 se_sess = transport_init_session(sup_prot_ops);
285 if (IS_ERR(se_sess))
286 return se_sess;
287
288 rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
289 if (rc < 0) {
290 transport_free_session(se_sess);
291 return ERR_PTR(-ENOMEM);
292 }
293
294 return se_sess;
295 }
296 EXPORT_SYMBOL(transport_init_session_tags);
297
298 /*
299 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
300 */
301 void __transport_register_session(
302 struct se_portal_group *se_tpg,
303 struct se_node_acl *se_nacl,
304 struct se_session *se_sess,
305 void *fabric_sess_ptr)
306 {
307 const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
308 unsigned char buf[PR_REG_ISID_LEN];
309
310 se_sess->se_tpg = se_tpg;
311 se_sess->fabric_sess_ptr = fabric_sess_ptr;
312 /*
313 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
314 *
315 * Only set for struct se_session's that will actually be moving I/O.
316 * eg: *NOT* discovery sessions.
317 */
318 if (se_nacl) {
319 /*
320 *
321 * Determine if fabric allows for T10-PI feature bits exposed to
322 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
323 *
324 * If so, then always save prot_type on a per se_node_acl node
325 * basis and re-instate the previous sess_prot_type to avoid
326 * disabling PI from below any previously initiator side
327 * registered LUNs.
328 */
329 if (se_nacl->saved_prot_type)
330 se_sess->sess_prot_type = se_nacl->saved_prot_type;
331 else if (tfo->tpg_check_prot_fabric_only)
332 se_sess->sess_prot_type = se_nacl->saved_prot_type =
333 tfo->tpg_check_prot_fabric_only(se_tpg);
334 /*
335 * If the fabric module supports an ISID based TransportID,
336 * save this value in binary from the fabric I_T Nexus now.
337 */
338 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
339 memset(&buf[0], 0, PR_REG_ISID_LEN);
340 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
341 &buf[0], PR_REG_ISID_LEN);
342 se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
343 }
344 kref_get(&se_nacl->acl_kref);
345
346 spin_lock_irq(&se_nacl->nacl_sess_lock);
347 /*
348 * The se_nacl->nacl_sess pointer will be set to the
349 * last active I_T Nexus for each struct se_node_acl.
350 */
351 se_nacl->nacl_sess = se_sess;
352
353 list_add_tail(&se_sess->sess_acl_list,
354 &se_nacl->acl_sess_list);
355 spin_unlock_irq(&se_nacl->nacl_sess_lock);
356 }
357 list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
358
359 pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
360 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
361 }
362 EXPORT_SYMBOL(__transport_register_session);
363
364 void transport_register_session(
365 struct se_portal_group *se_tpg,
366 struct se_node_acl *se_nacl,
367 struct se_session *se_sess,
368 void *fabric_sess_ptr)
369 {
370 unsigned long flags;
371
372 spin_lock_irqsave(&se_tpg->session_lock, flags);
373 __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
374 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
375 }
376 EXPORT_SYMBOL(transport_register_session);
377
378 static void target_release_session(struct kref *kref)
379 {
380 struct se_session *se_sess = container_of(kref,
381 struct se_session, sess_kref);
382 struct se_portal_group *se_tpg = se_sess->se_tpg;
383
384 se_tpg->se_tpg_tfo->close_session(se_sess);
385 }
386
387 void target_get_session(struct se_session *se_sess)
388 {
389 kref_get(&se_sess->sess_kref);
390 }
391 EXPORT_SYMBOL(target_get_session);
392
393 void target_put_session(struct se_session *se_sess)
394 {
395 kref_put(&se_sess->sess_kref, target_release_session);
396 }
397 EXPORT_SYMBOL(target_put_session);
398
399 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
400 {
401 struct se_session *se_sess;
402 ssize_t len = 0;
403
404 spin_lock_bh(&se_tpg->session_lock);
405 list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
406 if (!se_sess->se_node_acl)
407 continue;
408 if (!se_sess->se_node_acl->dynamic_node_acl)
409 continue;
410 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
411 break;
412
413 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
414 se_sess->se_node_acl->initiatorname);
415 len += 1; /* Include NULL terminator */
416 }
417 spin_unlock_bh(&se_tpg->session_lock);
418
419 return len;
420 }
421 EXPORT_SYMBOL(target_show_dynamic_sessions);
422
423 static void target_complete_nacl(struct kref *kref)
424 {
425 struct se_node_acl *nacl = container_of(kref,
426 struct se_node_acl, acl_kref);
427
428 complete(&nacl->acl_free_comp);
429 }
430
431 void target_put_nacl(struct se_node_acl *nacl)
432 {
433 kref_put(&nacl->acl_kref, target_complete_nacl);
434 }
435
436 void transport_deregister_session_configfs(struct se_session *se_sess)
437 {
438 struct se_node_acl *se_nacl;
439 unsigned long flags;
440 /*
441 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
442 */
443 se_nacl = se_sess->se_node_acl;
444 if (se_nacl) {
445 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
446 if (se_nacl->acl_stop == 0)
447 list_del(&se_sess->sess_acl_list);
448 /*
449 * If the session list is empty, then clear the pointer.
450 * Otherwise, set the struct se_session pointer from the tail
451 * element of the per struct se_node_acl active session list.
452 */
453 if (list_empty(&se_nacl->acl_sess_list))
454 se_nacl->nacl_sess = NULL;
455 else {
456 se_nacl->nacl_sess = container_of(
457 se_nacl->acl_sess_list.prev,
458 struct se_session, sess_acl_list);
459 }
460 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
461 }
462 }
463 EXPORT_SYMBOL(transport_deregister_session_configfs);
464
465 void transport_free_session(struct se_session *se_sess)
466 {
467 if (se_sess->sess_cmd_map) {
468 percpu_ida_destroy(&se_sess->sess_tag_pool);
469 kvfree(se_sess->sess_cmd_map);
470 }
471 kmem_cache_free(se_sess_cache, se_sess);
472 }
473 EXPORT_SYMBOL(transport_free_session);
474
475 void transport_deregister_session(struct se_session *se_sess)
476 {
477 struct se_portal_group *se_tpg = se_sess->se_tpg;
478 const struct target_core_fabric_ops *se_tfo;
479 struct se_node_acl *se_nacl;
480 unsigned long flags;
481 bool comp_nacl = true, drop_nacl = false;
482
483 if (!se_tpg) {
484 transport_free_session(se_sess);
485 return;
486 }
487 se_tfo = se_tpg->se_tpg_tfo;
488
489 spin_lock_irqsave(&se_tpg->session_lock, flags);
490 list_del(&se_sess->sess_list);
491 se_sess->se_tpg = NULL;
492 se_sess->fabric_sess_ptr = NULL;
493 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
494
495 /*
496 * Determine if we need to do extra work for this initiator node's
497 * struct se_node_acl if it had been previously dynamically generated.
498 */
499 se_nacl = se_sess->se_node_acl;
500
501 mutex_lock(&se_tpg->acl_node_mutex);
502 if (se_nacl && se_nacl->dynamic_node_acl) {
503 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
504 list_del(&se_nacl->acl_list);
505 se_tpg->num_node_acls--;
506 drop_nacl = true;
507 }
508 }
509 mutex_unlock(&se_tpg->acl_node_mutex);
510
511 if (drop_nacl) {
512 core_tpg_wait_for_nacl_pr_ref(se_nacl);
513 core_free_device_list_for_node(se_nacl, se_tpg);
514 kfree(se_nacl);
515 comp_nacl = false;
516 }
517 pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
518 se_tpg->se_tpg_tfo->get_fabric_name());
519 /*
520 * If last kref is dropping now for an explicit NodeACL, awake sleeping
521 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
522 * removal context.
523 */
524 if (se_nacl && comp_nacl)
525 target_put_nacl(se_nacl);
526
527 transport_free_session(se_sess);
528 }
529 EXPORT_SYMBOL(transport_deregister_session);
530
531 /*
532 * Called with cmd->t_state_lock held.
533 */
534 static void target_remove_from_state_list(struct se_cmd *cmd)
535 {
536 struct se_device *dev = cmd->se_dev;
537 unsigned long flags;
538
539 if (!dev)
540 return;
541
542 if (cmd->transport_state & CMD_T_BUSY)
543 return;
544
545 spin_lock_irqsave(&dev->execute_task_lock, flags);
546 if (cmd->state_active) {
547 list_del(&cmd->state_list);
548 cmd->state_active = false;
549 }
550 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
551 }
552
553 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
554 bool write_pending)
555 {
556 unsigned long flags;
557
558 spin_lock_irqsave(&cmd->t_state_lock, flags);
559 if (write_pending)
560 cmd->t_state = TRANSPORT_WRITE_PENDING;
561
562 if (remove_from_lists) {
563 target_remove_from_state_list(cmd);
564
565 /*
566 * Clear struct se_cmd->se_lun before the handoff to FE.
567 */
568 cmd->se_lun = NULL;
569 }
570
571 /*
572 * Determine if frontend context caller is requesting the stopping of
573 * this command for frontend exceptions.
574 */
575 if (cmd->transport_state & CMD_T_STOP) {
576 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
577 __func__, __LINE__, cmd->tag);
578
579 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
580
581 complete_all(&cmd->t_transport_stop_comp);
582 return 1;
583 }
584
585 cmd->transport_state &= ~CMD_T_ACTIVE;
586 if (remove_from_lists) {
587 /*
588 * Some fabric modules like tcm_loop can release
589 * their internally allocated I/O reference now and
590 * struct se_cmd now.
591 *
592 * Fabric modules are expected to return '1' here if the
593 * se_cmd being passed is released at this point,
594 * or zero if not being released.
595 */
596 if (cmd->se_tfo->check_stop_free != NULL) {
597 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
598 return cmd->se_tfo->check_stop_free(cmd);
599 }
600 }
601
602 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
603 return 0;
604 }
605
606 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
607 {
608 return transport_cmd_check_stop(cmd, true, false);
609 }
610
611 static void transport_lun_remove_cmd(struct se_cmd *cmd)
612 {
613 struct se_lun *lun = cmd->se_lun;
614
615 if (!lun)
616 return;
617
618 if (cmpxchg(&cmd->lun_ref_active, true, false))
619 percpu_ref_put(&lun->lun_ref);
620 }
621
622 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
623 {
624 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
625 transport_lun_remove_cmd(cmd);
626 /*
627 * Allow the fabric driver to unmap any resources before
628 * releasing the descriptor via TFO->release_cmd()
629 */
630 if (remove)
631 cmd->se_tfo->aborted_task(cmd);
632
633 if (transport_cmd_check_stop_to_fabric(cmd))
634 return;
635 if (remove)
636 transport_put_cmd(cmd);
637 }
638
639 static void target_complete_failure_work(struct work_struct *work)
640 {
641 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
642
643 transport_generic_request_failure(cmd,
644 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
645 }
646
647 /*
648 * Used when asking transport to copy Sense Data from the underlying
649 * Linux/SCSI struct scsi_cmnd
650 */
651 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
652 {
653 struct se_device *dev = cmd->se_dev;
654
655 WARN_ON(!cmd->se_lun);
656
657 if (!dev)
658 return NULL;
659
660 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
661 return NULL;
662
663 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
664
665 pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
666 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
667 return cmd->sense_buffer;
668 }
669
670 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
671 {
672 struct se_device *dev = cmd->se_dev;
673 int success = scsi_status == GOOD;
674 unsigned long flags;
675
676 cmd->scsi_status = scsi_status;
677
678
679 spin_lock_irqsave(&cmd->t_state_lock, flags);
680 cmd->transport_state &= ~CMD_T_BUSY;
681
682 if (dev && dev->transport->transport_complete) {
683 dev->transport->transport_complete(cmd,
684 cmd->t_data_sg,
685 transport_get_sense_buffer(cmd));
686 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
687 success = 1;
688 }
689
690 /*
691 * See if we are waiting to complete for an exception condition.
692 */
693 if (cmd->transport_state & CMD_T_REQUEST_STOP) {
694 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
695 complete(&cmd->task_stop_comp);
696 return;
697 }
698
699 /*
700 * Check for case where an explicit ABORT_TASK has been received
701 * and transport_wait_for_tasks() will be waiting for completion..
702 */
703 if (cmd->transport_state & CMD_T_ABORTED &&
704 cmd->transport_state & CMD_T_STOP) {
705 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
706 complete_all(&cmd->t_transport_stop_comp);
707 return;
708 } else if (!success) {
709 INIT_WORK(&cmd->work, target_complete_failure_work);
710 } else {
711 INIT_WORK(&cmd->work, target_complete_ok_work);
712 }
713
714 cmd->t_state = TRANSPORT_COMPLETE;
715 cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
716 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
717
718 queue_work(target_completion_wq, &cmd->work);
719 }
720 EXPORT_SYMBOL(target_complete_cmd);
721
722 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
723 {
724 if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
725 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
726 cmd->residual_count += cmd->data_length - length;
727 } else {
728 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
729 cmd->residual_count = cmd->data_length - length;
730 }
731
732 cmd->data_length = length;
733 }
734
735 target_complete_cmd(cmd, scsi_status);
736 }
737 EXPORT_SYMBOL(target_complete_cmd_with_length);
738
739 static void target_add_to_state_list(struct se_cmd *cmd)
740 {
741 struct se_device *dev = cmd->se_dev;
742 unsigned long flags;
743
744 spin_lock_irqsave(&dev->execute_task_lock, flags);
745 if (!cmd->state_active) {
746 list_add_tail(&cmd->state_list, &dev->state_list);
747 cmd->state_active = true;
748 }
749 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
750 }
751
752 /*
753 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
754 */
755 static void transport_write_pending_qf(struct se_cmd *cmd);
756 static void transport_complete_qf(struct se_cmd *cmd);
757
758 void target_qf_do_work(struct work_struct *work)
759 {
760 struct se_device *dev = container_of(work, struct se_device,
761 qf_work_queue);
762 LIST_HEAD(qf_cmd_list);
763 struct se_cmd *cmd, *cmd_tmp;
764
765 spin_lock_irq(&dev->qf_cmd_lock);
766 list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
767 spin_unlock_irq(&dev->qf_cmd_lock);
768
769 list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
770 list_del(&cmd->se_qf_node);
771 atomic_dec_mb(&dev->dev_qf_count);
772
773 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
774 " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
775 (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
776 (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
777 : "UNKNOWN");
778
779 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
780 transport_write_pending_qf(cmd);
781 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
782 transport_complete_qf(cmd);
783 }
784 }
785
786 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
787 {
788 switch (cmd->data_direction) {
789 case DMA_NONE:
790 return "NONE";
791 case DMA_FROM_DEVICE:
792 return "READ";
793 case DMA_TO_DEVICE:
794 return "WRITE";
795 case DMA_BIDIRECTIONAL:
796 return "BIDI";
797 default:
798 break;
799 }
800
801 return "UNKNOWN";
802 }
803
804 void transport_dump_dev_state(
805 struct se_device *dev,
806 char *b,
807 int *bl)
808 {
809 *bl += sprintf(b + *bl, "Status: ");
810 if (dev->export_count)
811 *bl += sprintf(b + *bl, "ACTIVATED");
812 else
813 *bl += sprintf(b + *bl, "DEACTIVATED");
814
815 *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
816 *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
817 dev->dev_attrib.block_size,
818 dev->dev_attrib.hw_max_sectors);
819 *bl += sprintf(b + *bl, " ");
820 }
821
822 void transport_dump_vpd_proto_id(
823 struct t10_vpd *vpd,
824 unsigned char *p_buf,
825 int p_buf_len)
826 {
827 unsigned char buf[VPD_TMP_BUF_SIZE];
828 int len;
829
830 memset(buf, 0, VPD_TMP_BUF_SIZE);
831 len = sprintf(buf, "T10 VPD Protocol Identifier: ");
832
833 switch (vpd->protocol_identifier) {
834 case 0x00:
835 sprintf(buf+len, "Fibre Channel\n");
836 break;
837 case 0x10:
838 sprintf(buf+len, "Parallel SCSI\n");
839 break;
840 case 0x20:
841 sprintf(buf+len, "SSA\n");
842 break;
843 case 0x30:
844 sprintf(buf+len, "IEEE 1394\n");
845 break;
846 case 0x40:
847 sprintf(buf+len, "SCSI Remote Direct Memory Access"
848 " Protocol\n");
849 break;
850 case 0x50:
851 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
852 break;
853 case 0x60:
854 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
855 break;
856 case 0x70:
857 sprintf(buf+len, "Automation/Drive Interface Transport"
858 " Protocol\n");
859 break;
860 case 0x80:
861 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
862 break;
863 default:
864 sprintf(buf+len, "Unknown 0x%02x\n",
865 vpd->protocol_identifier);
866 break;
867 }
868
869 if (p_buf)
870 strncpy(p_buf, buf, p_buf_len);
871 else
872 pr_debug("%s", buf);
873 }
874
875 void
876 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
877 {
878 /*
879 * Check if the Protocol Identifier Valid (PIV) bit is set..
880 *
881 * from spc3r23.pdf section 7.5.1
882 */
883 if (page_83[1] & 0x80) {
884 vpd->protocol_identifier = (page_83[0] & 0xf0);
885 vpd->protocol_identifier_set = 1;
886 transport_dump_vpd_proto_id(vpd, NULL, 0);
887 }
888 }
889 EXPORT_SYMBOL(transport_set_vpd_proto_id);
890
891 int transport_dump_vpd_assoc(
892 struct t10_vpd *vpd,
893 unsigned char *p_buf,
894 int p_buf_len)
895 {
896 unsigned char buf[VPD_TMP_BUF_SIZE];
897 int ret = 0;
898 int len;
899
900 memset(buf, 0, VPD_TMP_BUF_SIZE);
901 len = sprintf(buf, "T10 VPD Identifier Association: ");
902
903 switch (vpd->association) {
904 case 0x00:
905 sprintf(buf+len, "addressed logical unit\n");
906 break;
907 case 0x10:
908 sprintf(buf+len, "target port\n");
909 break;
910 case 0x20:
911 sprintf(buf+len, "SCSI target device\n");
912 break;
913 default:
914 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
915 ret = -EINVAL;
916 break;
917 }
918
919 if (p_buf)
920 strncpy(p_buf, buf, p_buf_len);
921 else
922 pr_debug("%s", buf);
923
924 return ret;
925 }
926
927 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
928 {
929 /*
930 * The VPD identification association..
931 *
932 * from spc3r23.pdf Section 7.6.3.1 Table 297
933 */
934 vpd->association = (page_83[1] & 0x30);
935 return transport_dump_vpd_assoc(vpd, NULL, 0);
936 }
937 EXPORT_SYMBOL(transport_set_vpd_assoc);
938
939 int transport_dump_vpd_ident_type(
940 struct t10_vpd *vpd,
941 unsigned char *p_buf,
942 int p_buf_len)
943 {
944 unsigned char buf[VPD_TMP_BUF_SIZE];
945 int ret = 0;
946 int len;
947
948 memset(buf, 0, VPD_TMP_BUF_SIZE);
949 len = sprintf(buf, "T10 VPD Identifier Type: ");
950
951 switch (vpd->device_identifier_type) {
952 case 0x00:
953 sprintf(buf+len, "Vendor specific\n");
954 break;
955 case 0x01:
956 sprintf(buf+len, "T10 Vendor ID based\n");
957 break;
958 case 0x02:
959 sprintf(buf+len, "EUI-64 based\n");
960 break;
961 case 0x03:
962 sprintf(buf+len, "NAA\n");
963 break;
964 case 0x04:
965 sprintf(buf+len, "Relative target port identifier\n");
966 break;
967 case 0x08:
968 sprintf(buf+len, "SCSI name string\n");
969 break;
970 default:
971 sprintf(buf+len, "Unsupported: 0x%02x\n",
972 vpd->device_identifier_type);
973 ret = -EINVAL;
974 break;
975 }
976
977 if (p_buf) {
978 if (p_buf_len < strlen(buf)+1)
979 return -EINVAL;
980 strncpy(p_buf, buf, p_buf_len);
981 } else {
982 pr_debug("%s", buf);
983 }
984
985 return ret;
986 }
987
988 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
989 {
990 /*
991 * The VPD identifier type..
992 *
993 * from spc3r23.pdf Section 7.6.3.1 Table 298
994 */
995 vpd->device_identifier_type = (page_83[1] & 0x0f);
996 return transport_dump_vpd_ident_type(vpd, NULL, 0);
997 }
998 EXPORT_SYMBOL(transport_set_vpd_ident_type);
999
1000 int transport_dump_vpd_ident(
1001 struct t10_vpd *vpd,
1002 unsigned char *p_buf,
1003 int p_buf_len)
1004 {
1005 unsigned char buf[VPD_TMP_BUF_SIZE];
1006 int ret = 0;
1007
1008 memset(buf, 0, VPD_TMP_BUF_SIZE);
1009
1010 switch (vpd->device_identifier_code_set) {
1011 case 0x01: /* Binary */
1012 snprintf(buf, sizeof(buf),
1013 "T10 VPD Binary Device Identifier: %s\n",
1014 &vpd->device_identifier[0]);
1015 break;
1016 case 0x02: /* ASCII */
1017 snprintf(buf, sizeof(buf),
1018 "T10 VPD ASCII Device Identifier: %s\n",
1019 &vpd->device_identifier[0]);
1020 break;
1021 case 0x03: /* UTF-8 */
1022 snprintf(buf, sizeof(buf),
1023 "T10 VPD UTF-8 Device Identifier: %s\n",
1024 &vpd->device_identifier[0]);
1025 break;
1026 default:
1027 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1028 " 0x%02x", vpd->device_identifier_code_set);
1029 ret = -EINVAL;
1030 break;
1031 }
1032
1033 if (p_buf)
1034 strncpy(p_buf, buf, p_buf_len);
1035 else
1036 pr_debug("%s", buf);
1037
1038 return ret;
1039 }
1040
1041 int
1042 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1043 {
1044 static const char hex_str[] = "0123456789abcdef";
1045 int j = 0, i = 4; /* offset to start of the identifier */
1046
1047 /*
1048 * The VPD Code Set (encoding)
1049 *
1050 * from spc3r23.pdf Section 7.6.3.1 Table 296
1051 */
1052 vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1053 switch (vpd->device_identifier_code_set) {
1054 case 0x01: /* Binary */
1055 vpd->device_identifier[j++] =
1056 hex_str[vpd->device_identifier_type];
1057 while (i < (4 + page_83[3])) {
1058 vpd->device_identifier[j++] =
1059 hex_str[(page_83[i] & 0xf0) >> 4];
1060 vpd->device_identifier[j++] =
1061 hex_str[page_83[i] & 0x0f];
1062 i++;
1063 }
1064 break;
1065 case 0x02: /* ASCII */
1066 case 0x03: /* UTF-8 */
1067 while (i < (4 + page_83[3]))
1068 vpd->device_identifier[j++] = page_83[i++];
1069 break;
1070 default:
1071 break;
1072 }
1073
1074 return transport_dump_vpd_ident(vpd, NULL, 0);
1075 }
1076 EXPORT_SYMBOL(transport_set_vpd_ident);
1077
1078 static sense_reason_t
1079 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1080 unsigned int size)
1081 {
1082 u32 mtl;
1083
1084 if (!cmd->se_tfo->max_data_sg_nents)
1085 return TCM_NO_SENSE;
1086 /*
1087 * Check if fabric enforced maximum SGL entries per I/O descriptor
1088 * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT +
1089 * residual_count and reduce original cmd->data_length to maximum
1090 * length based on single PAGE_SIZE entry scatter-lists.
1091 */
1092 mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1093 if (cmd->data_length > mtl) {
1094 /*
1095 * If an existing CDB overflow is present, calculate new residual
1096 * based on CDB size minus fabric maximum transfer length.
1097 *
1098 * If an existing CDB underflow is present, calculate new residual
1099 * based on original cmd->data_length minus fabric maximum transfer
1100 * length.
1101 *
1102 * Otherwise, set the underflow residual based on cmd->data_length
1103 * minus fabric maximum transfer length.
1104 */
1105 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1106 cmd->residual_count = (size - mtl);
1107 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1108 u32 orig_dl = size + cmd->residual_count;
1109 cmd->residual_count = (orig_dl - mtl);
1110 } else {
1111 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1112 cmd->residual_count = (cmd->data_length - mtl);
1113 }
1114 cmd->data_length = mtl;
1115 /*
1116 * Reset sbc_check_prot() calculated protection payload
1117 * length based upon the new smaller MTL.
1118 */
1119 if (cmd->prot_length) {
1120 u32 sectors = (mtl / dev->dev_attrib.block_size);
1121 cmd->prot_length = dev->prot_length * sectors;
1122 }
1123 }
1124 return TCM_NO_SENSE;
1125 }
1126
1127 sense_reason_t
1128 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1129 {
1130 struct se_device *dev = cmd->se_dev;
1131
1132 if (cmd->unknown_data_length) {
1133 cmd->data_length = size;
1134 } else if (size != cmd->data_length) {
1135 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1136 " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1137 " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1138 cmd->data_length, size, cmd->t_task_cdb[0]);
1139
1140 if (cmd->data_direction == DMA_TO_DEVICE &&
1141 cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1142 pr_err("Rejecting underflow/overflow WRITE data\n");
1143 return TCM_INVALID_CDB_FIELD;
1144 }
1145 /*
1146 * Reject READ_* or WRITE_* with overflow/underflow for
1147 * type SCF_SCSI_DATA_CDB.
1148 */
1149 if (dev->dev_attrib.block_size != 512) {
1150 pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1151 " CDB on non 512-byte sector setup subsystem"
1152 " plugin: %s\n", dev->transport->name);
1153 /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1154 return TCM_INVALID_CDB_FIELD;
1155 }
1156 /*
1157 * For the overflow case keep the existing fabric provided
1158 * ->data_length. Otherwise for the underflow case, reset
1159 * ->data_length to the smaller SCSI expected data transfer
1160 * length.
1161 */
1162 if (size > cmd->data_length) {
1163 cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1164 cmd->residual_count = (size - cmd->data_length);
1165 } else {
1166 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1167 cmd->residual_count = (cmd->data_length - size);
1168 cmd->data_length = size;
1169 }
1170 }
1171
1172 return target_check_max_data_sg_nents(cmd, dev, size);
1173
1174 }
1175
1176 /*
1177 * Used by fabric modules containing a local struct se_cmd within their
1178 * fabric dependent per I/O descriptor.
1179 *
1180 * Preserves the value of @cmd->tag.
1181 */
1182 void transport_init_se_cmd(
1183 struct se_cmd *cmd,
1184 const struct target_core_fabric_ops *tfo,
1185 struct se_session *se_sess,
1186 u32 data_length,
1187 int data_direction,
1188 int task_attr,
1189 unsigned char *sense_buffer)
1190 {
1191 INIT_LIST_HEAD(&cmd->se_delayed_node);
1192 INIT_LIST_HEAD(&cmd->se_qf_node);
1193 INIT_LIST_HEAD(&cmd->se_cmd_list);
1194 INIT_LIST_HEAD(&cmd->state_list);
1195 init_completion(&cmd->t_transport_stop_comp);
1196 init_completion(&cmd->cmd_wait_comp);
1197 init_completion(&cmd->task_stop_comp);
1198 spin_lock_init(&cmd->t_state_lock);
1199 kref_init(&cmd->cmd_kref);
1200 cmd->transport_state = CMD_T_DEV_ACTIVE;
1201
1202 cmd->se_tfo = tfo;
1203 cmd->se_sess = se_sess;
1204 cmd->data_length = data_length;
1205 cmd->data_direction = data_direction;
1206 cmd->sam_task_attr = task_attr;
1207 cmd->sense_buffer = sense_buffer;
1208
1209 cmd->state_active = false;
1210 }
1211 EXPORT_SYMBOL(transport_init_se_cmd);
1212
1213 static sense_reason_t
1214 transport_check_alloc_task_attr(struct se_cmd *cmd)
1215 {
1216 struct se_device *dev = cmd->se_dev;
1217
1218 /*
1219 * Check if SAM Task Attribute emulation is enabled for this
1220 * struct se_device storage object
1221 */
1222 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1223 return 0;
1224
1225 if (cmd->sam_task_attr == TCM_ACA_TAG) {
1226 pr_debug("SAM Task Attribute ACA"
1227 " emulation is not supported\n");
1228 return TCM_INVALID_CDB_FIELD;
1229 }
1230
1231 return 0;
1232 }
1233
1234 sense_reason_t
1235 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1236 {
1237 struct se_device *dev = cmd->se_dev;
1238 sense_reason_t ret;
1239
1240 /*
1241 * Ensure that the received CDB is less than the max (252 + 8) bytes
1242 * for VARIABLE_LENGTH_CMD
1243 */
1244 if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1245 pr_err("Received SCSI CDB with command_size: %d that"
1246 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1247 scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1248 return TCM_INVALID_CDB_FIELD;
1249 }
1250 /*
1251 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1252 * allocate the additional extended CDB buffer now.. Otherwise
1253 * setup the pointer from __t_task_cdb to t_task_cdb.
1254 */
1255 if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1256 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1257 GFP_KERNEL);
1258 if (!cmd->t_task_cdb) {
1259 pr_err("Unable to allocate cmd->t_task_cdb"
1260 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1261 scsi_command_size(cdb),
1262 (unsigned long)sizeof(cmd->__t_task_cdb));
1263 return TCM_OUT_OF_RESOURCES;
1264 }
1265 } else
1266 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1267 /*
1268 * Copy the original CDB into cmd->
1269 */
1270 memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1271
1272 trace_target_sequencer_start(cmd);
1273
1274 /*
1275 * Check for an existing UNIT ATTENTION condition
1276 */
1277 ret = target_scsi3_ua_check(cmd);
1278 if (ret)
1279 return ret;
1280
1281 ret = target_alua_state_check(cmd);
1282 if (ret)
1283 return ret;
1284
1285 ret = target_check_reservation(cmd);
1286 if (ret) {
1287 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1288 return ret;
1289 }
1290
1291 ret = dev->transport->parse_cdb(cmd);
1292 if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1293 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1294 cmd->se_tfo->get_fabric_name(),
1295 cmd->se_sess->se_node_acl->initiatorname,
1296 cmd->t_task_cdb[0]);
1297 if (ret)
1298 return ret;
1299
1300 ret = transport_check_alloc_task_attr(cmd);
1301 if (ret)
1302 return ret;
1303
1304 cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1305 atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1306 return 0;
1307 }
1308 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1309
1310 /*
1311 * Used by fabric module frontends to queue tasks directly.
1312 * Many only be used from process context only
1313 */
1314 int transport_handle_cdb_direct(
1315 struct se_cmd *cmd)
1316 {
1317 sense_reason_t ret;
1318
1319 if (!cmd->se_lun) {
1320 dump_stack();
1321 pr_err("cmd->se_lun is NULL\n");
1322 return -EINVAL;
1323 }
1324 if (in_interrupt()) {
1325 dump_stack();
1326 pr_err("transport_generic_handle_cdb cannot be called"
1327 " from interrupt context\n");
1328 return -EINVAL;
1329 }
1330 /*
1331 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1332 * outstanding descriptors are handled correctly during shutdown via
1333 * transport_wait_for_tasks()
1334 *
1335 * Also, we don't take cmd->t_state_lock here as we only expect
1336 * this to be called for initial descriptor submission.
1337 */
1338 cmd->t_state = TRANSPORT_NEW_CMD;
1339 cmd->transport_state |= CMD_T_ACTIVE;
1340
1341 /*
1342 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1343 * so follow TRANSPORT_NEW_CMD processing thread context usage
1344 * and call transport_generic_request_failure() if necessary..
1345 */
1346 ret = transport_generic_new_cmd(cmd);
1347 if (ret)
1348 transport_generic_request_failure(cmd, ret);
1349 return 0;
1350 }
1351 EXPORT_SYMBOL(transport_handle_cdb_direct);
1352
1353 sense_reason_t
1354 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1355 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1356 {
1357 if (!sgl || !sgl_count)
1358 return 0;
1359
1360 /*
1361 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1362 * scatterlists already have been set to follow what the fabric
1363 * passes for the original expected data transfer length.
1364 */
1365 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1366 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1367 " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1368 return TCM_INVALID_CDB_FIELD;
1369 }
1370
1371 cmd->t_data_sg = sgl;
1372 cmd->t_data_nents = sgl_count;
1373 cmd->t_bidi_data_sg = sgl_bidi;
1374 cmd->t_bidi_data_nents = sgl_bidi_count;
1375
1376 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1377 return 0;
1378 }
1379
1380 /*
1381 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1382 * se_cmd + use pre-allocated SGL memory.
1383 *
1384 * @se_cmd: command descriptor to submit
1385 * @se_sess: associated se_sess for endpoint
1386 * @cdb: pointer to SCSI CDB
1387 * @sense: pointer to SCSI sense buffer
1388 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1389 * @data_length: fabric expected data transfer length
1390 * @task_addr: SAM task attribute
1391 * @data_dir: DMA data direction
1392 * @flags: flags for command submission from target_sc_flags_tables
1393 * @sgl: struct scatterlist memory for unidirectional mapping
1394 * @sgl_count: scatterlist count for unidirectional mapping
1395 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1396 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1397 * @sgl_prot: struct scatterlist memory protection information
1398 * @sgl_prot_count: scatterlist count for protection information
1399 *
1400 * Task tags are supported if the caller has set @se_cmd->tag.
1401 *
1402 * Returns non zero to signal active I/O shutdown failure. All other
1403 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1404 * but still return zero here.
1405 *
1406 * This may only be called from process context, and also currently
1407 * assumes internal allocation of fabric payload buffer by target-core.
1408 */
1409 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1410 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1411 u32 data_length, int task_attr, int data_dir, int flags,
1412 struct scatterlist *sgl, u32 sgl_count,
1413 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1414 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1415 {
1416 struct se_portal_group *se_tpg;
1417 sense_reason_t rc;
1418 int ret;
1419
1420 se_tpg = se_sess->se_tpg;
1421 BUG_ON(!se_tpg);
1422 BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1423 BUG_ON(in_interrupt());
1424 /*
1425 * Initialize se_cmd for target operation. From this point
1426 * exceptions are handled by sending exception status via
1427 * target_core_fabric_ops->queue_status() callback
1428 */
1429 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1430 data_length, data_dir, task_attr, sense);
1431 if (flags & TARGET_SCF_UNKNOWN_SIZE)
1432 se_cmd->unknown_data_length = 1;
1433 /*
1434 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1435 * se_sess->sess_cmd_list. A second kref_get here is necessary
1436 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1437 * kref_put() to happen during fabric packet acknowledgement.
1438 */
1439 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1440 if (ret)
1441 return ret;
1442 /*
1443 * Signal bidirectional data payloads to target-core
1444 */
1445 if (flags & TARGET_SCF_BIDI_OP)
1446 se_cmd->se_cmd_flags |= SCF_BIDI;
1447 /*
1448 * Locate se_lun pointer and attach it to struct se_cmd
1449 */
1450 rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1451 if (rc) {
1452 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1453 target_put_sess_cmd(se_cmd);
1454 return 0;
1455 }
1456
1457 rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1458 if (rc != 0) {
1459 transport_generic_request_failure(se_cmd, rc);
1460 return 0;
1461 }
1462
1463 /*
1464 * Save pointers for SGLs containing protection information,
1465 * if present.
1466 */
1467 if (sgl_prot_count) {
1468 se_cmd->t_prot_sg = sgl_prot;
1469 se_cmd->t_prot_nents = sgl_prot_count;
1470 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1471 }
1472
1473 /*
1474 * When a non zero sgl_count has been passed perform SGL passthrough
1475 * mapping for pre-allocated fabric memory instead of having target
1476 * core perform an internal SGL allocation..
1477 */
1478 if (sgl_count != 0) {
1479 BUG_ON(!sgl);
1480
1481 /*
1482 * A work-around for tcm_loop as some userspace code via
1483 * scsi-generic do not memset their associated read buffers,
1484 * so go ahead and do that here for type non-data CDBs. Also
1485 * note that this is currently guaranteed to be a single SGL
1486 * for this case by target core in target_setup_cmd_from_cdb()
1487 * -> transport_generic_cmd_sequencer().
1488 */
1489 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1490 se_cmd->data_direction == DMA_FROM_DEVICE) {
1491 unsigned char *buf = NULL;
1492
1493 if (sgl)
1494 buf = kmap(sg_page(sgl)) + sgl->offset;
1495
1496 if (buf) {
1497 memset(buf, 0, sgl->length);
1498 kunmap(sg_page(sgl));
1499 }
1500 }
1501
1502 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1503 sgl_bidi, sgl_bidi_count);
1504 if (rc != 0) {
1505 transport_generic_request_failure(se_cmd, rc);
1506 return 0;
1507 }
1508 }
1509
1510 /*
1511 * Check if we need to delay processing because of ALUA
1512 * Active/NonOptimized primary access state..
1513 */
1514 core_alua_check_nonop_delay(se_cmd);
1515
1516 transport_handle_cdb_direct(se_cmd);
1517 return 0;
1518 }
1519 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1520
1521 /*
1522 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1523 *
1524 * @se_cmd: command descriptor to submit
1525 * @se_sess: associated se_sess for endpoint
1526 * @cdb: pointer to SCSI CDB
1527 * @sense: pointer to SCSI sense buffer
1528 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1529 * @data_length: fabric expected data transfer length
1530 * @task_addr: SAM task attribute
1531 * @data_dir: DMA data direction
1532 * @flags: flags for command submission from target_sc_flags_tables
1533 *
1534 * Task tags are supported if the caller has set @se_cmd->tag.
1535 *
1536 * Returns non zero to signal active I/O shutdown failure. All other
1537 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1538 * but still return zero here.
1539 *
1540 * This may only be called from process context, and also currently
1541 * assumes internal allocation of fabric payload buffer by target-core.
1542 *
1543 * It also assumes interal target core SGL memory allocation.
1544 */
1545 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1546 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1547 u32 data_length, int task_attr, int data_dir, int flags)
1548 {
1549 return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1550 unpacked_lun, data_length, task_attr, data_dir,
1551 flags, NULL, 0, NULL, 0, NULL, 0);
1552 }
1553 EXPORT_SYMBOL(target_submit_cmd);
1554
1555 static void target_complete_tmr_failure(struct work_struct *work)
1556 {
1557 struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1558
1559 se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1560 se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1561
1562 transport_cmd_check_stop_to_fabric(se_cmd);
1563 }
1564
1565 /**
1566 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1567 * for TMR CDBs
1568 *
1569 * @se_cmd: command descriptor to submit
1570 * @se_sess: associated se_sess for endpoint
1571 * @sense: pointer to SCSI sense buffer
1572 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1573 * @fabric_context: fabric context for TMR req
1574 * @tm_type: Type of TM request
1575 * @gfp: gfp type for caller
1576 * @tag: referenced task tag for TMR_ABORT_TASK
1577 * @flags: submit cmd flags
1578 *
1579 * Callable from all contexts.
1580 **/
1581
1582 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1583 unsigned char *sense, u64 unpacked_lun,
1584 void *fabric_tmr_ptr, unsigned char tm_type,
1585 gfp_t gfp, unsigned int tag, int flags)
1586 {
1587 struct se_portal_group *se_tpg;
1588 int ret;
1589
1590 se_tpg = se_sess->se_tpg;
1591 BUG_ON(!se_tpg);
1592
1593 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1594 0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1595 /*
1596 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1597 * allocation failure.
1598 */
1599 ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1600 if (ret < 0)
1601 return -ENOMEM;
1602
1603 if (tm_type == TMR_ABORT_TASK)
1604 se_cmd->se_tmr_req->ref_task_tag = tag;
1605
1606 /* See target_submit_cmd for commentary */
1607 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1608 if (ret) {
1609 core_tmr_release_req(se_cmd->se_tmr_req);
1610 return ret;
1611 }
1612
1613 ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1614 if (ret) {
1615 /*
1616 * For callback during failure handling, push this work off
1617 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1618 */
1619 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1620 schedule_work(&se_cmd->work);
1621 return 0;
1622 }
1623 transport_generic_handle_tmr(se_cmd);
1624 return 0;
1625 }
1626 EXPORT_SYMBOL(target_submit_tmr);
1627
1628 /*
1629 * If the cmd is active, request it to be stopped and sleep until it
1630 * has completed.
1631 */
1632 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1633 __releases(&cmd->t_state_lock)
1634 __acquires(&cmd->t_state_lock)
1635 {
1636 bool was_active = false;
1637
1638 if (cmd->transport_state & CMD_T_BUSY) {
1639 cmd->transport_state |= CMD_T_REQUEST_STOP;
1640 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1641
1642 pr_debug("cmd %p waiting to complete\n", cmd);
1643 wait_for_completion(&cmd->task_stop_comp);
1644 pr_debug("cmd %p stopped successfully\n", cmd);
1645
1646 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1647 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1648 cmd->transport_state &= ~CMD_T_BUSY;
1649 was_active = true;
1650 }
1651
1652 return was_active;
1653 }
1654
1655 /*
1656 * Handle SAM-esque emulation for generic transport request failures.
1657 */
1658 void transport_generic_request_failure(struct se_cmd *cmd,
1659 sense_reason_t sense_reason)
1660 {
1661 int ret = 0;
1662
1663 pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08llx"
1664 " CDB: 0x%02x\n", cmd, cmd->tag, cmd->t_task_cdb[0]);
1665 pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1666 cmd->se_tfo->get_cmd_state(cmd),
1667 cmd->t_state, sense_reason);
1668 pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1669 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1670 (cmd->transport_state & CMD_T_STOP) != 0,
1671 (cmd->transport_state & CMD_T_SENT) != 0);
1672
1673 /*
1674 * For SAM Task Attribute emulation for failed struct se_cmd
1675 */
1676 transport_complete_task_attr(cmd);
1677 /*
1678 * Handle special case for COMPARE_AND_WRITE failure, where the
1679 * callback is expected to drop the per device ->caw_sem.
1680 */
1681 if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1682 cmd->transport_complete_callback)
1683 cmd->transport_complete_callback(cmd, false);
1684
1685 switch (sense_reason) {
1686 case TCM_NON_EXISTENT_LUN:
1687 case TCM_UNSUPPORTED_SCSI_OPCODE:
1688 case TCM_INVALID_CDB_FIELD:
1689 case TCM_INVALID_PARAMETER_LIST:
1690 case TCM_PARAMETER_LIST_LENGTH_ERROR:
1691 case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1692 case TCM_UNKNOWN_MODE_PAGE:
1693 case TCM_WRITE_PROTECTED:
1694 case TCM_ADDRESS_OUT_OF_RANGE:
1695 case TCM_CHECK_CONDITION_ABORT_CMD:
1696 case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1697 case TCM_CHECK_CONDITION_NOT_READY:
1698 case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1699 case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1700 case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1701 break;
1702 case TCM_OUT_OF_RESOURCES:
1703 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1704 break;
1705 case TCM_RESERVATION_CONFLICT:
1706 /*
1707 * No SENSE Data payload for this case, set SCSI Status
1708 * and queue the response to $FABRIC_MOD.
1709 *
1710 * Uses linux/include/scsi/scsi.h SAM status codes defs
1711 */
1712 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1713 /*
1714 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1715 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1716 * CONFLICT STATUS.
1717 *
1718 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1719 */
1720 if (cmd->se_sess &&
1721 cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1722 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1723 cmd->orig_fe_lun, 0x2C,
1724 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1725 }
1726 trace_target_cmd_complete(cmd);
1727 ret = cmd->se_tfo->queue_status(cmd);
1728 if (ret == -EAGAIN || ret == -ENOMEM)
1729 goto queue_full;
1730 goto check_stop;
1731 default:
1732 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1733 cmd->t_task_cdb[0], sense_reason);
1734 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1735 break;
1736 }
1737
1738 ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1739 if (ret == -EAGAIN || ret == -ENOMEM)
1740 goto queue_full;
1741
1742 check_stop:
1743 transport_lun_remove_cmd(cmd);
1744 transport_cmd_check_stop_to_fabric(cmd);
1745 return;
1746
1747 queue_full:
1748 cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1749 transport_handle_queue_full(cmd, cmd->se_dev);
1750 }
1751 EXPORT_SYMBOL(transport_generic_request_failure);
1752
1753 void __target_execute_cmd(struct se_cmd *cmd)
1754 {
1755 sense_reason_t ret;
1756
1757 if (cmd->execute_cmd) {
1758 ret = cmd->execute_cmd(cmd);
1759 if (ret) {
1760 spin_lock_irq(&cmd->t_state_lock);
1761 cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1762 spin_unlock_irq(&cmd->t_state_lock);
1763
1764 transport_generic_request_failure(cmd, ret);
1765 }
1766 }
1767 }
1768
1769 static int target_write_prot_action(struct se_cmd *cmd)
1770 {
1771 u32 sectors;
1772 /*
1773 * Perform WRITE_INSERT of PI using software emulation when backend
1774 * device has PI enabled, if the transport has not already generated
1775 * PI using hardware WRITE_INSERT offload.
1776 */
1777 switch (cmd->prot_op) {
1778 case TARGET_PROT_DOUT_INSERT:
1779 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1780 sbc_dif_generate(cmd);
1781 break;
1782 case TARGET_PROT_DOUT_STRIP:
1783 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1784 break;
1785
1786 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1787 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1788 sectors, 0, cmd->t_prot_sg, 0);
1789 if (unlikely(cmd->pi_err)) {
1790 spin_lock_irq(&cmd->t_state_lock);
1791 cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1792 spin_unlock_irq(&cmd->t_state_lock);
1793 transport_generic_request_failure(cmd, cmd->pi_err);
1794 return -1;
1795 }
1796 break;
1797 default:
1798 break;
1799 }
1800
1801 return 0;
1802 }
1803
1804 static bool target_handle_task_attr(struct se_cmd *cmd)
1805 {
1806 struct se_device *dev = cmd->se_dev;
1807
1808 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1809 return false;
1810
1811 /*
1812 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1813 * to allow the passed struct se_cmd list of tasks to the front of the list.
1814 */
1815 switch (cmd->sam_task_attr) {
1816 case TCM_HEAD_TAG:
1817 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1818 cmd->t_task_cdb[0]);
1819 return false;
1820 case TCM_ORDERED_TAG:
1821 atomic_inc_mb(&dev->dev_ordered_sync);
1822
1823 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1824 cmd->t_task_cdb[0]);
1825
1826 /*
1827 * Execute an ORDERED command if no other older commands
1828 * exist that need to be completed first.
1829 */
1830 if (!atomic_read(&dev->simple_cmds))
1831 return false;
1832 break;
1833 default:
1834 /*
1835 * For SIMPLE and UNTAGGED Task Attribute commands
1836 */
1837 atomic_inc_mb(&dev->simple_cmds);
1838 break;
1839 }
1840
1841 if (atomic_read(&dev->dev_ordered_sync) == 0)
1842 return false;
1843
1844 spin_lock(&dev->delayed_cmd_lock);
1845 list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1846 spin_unlock(&dev->delayed_cmd_lock);
1847
1848 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
1849 cmd->t_task_cdb[0], cmd->sam_task_attr);
1850 return true;
1851 }
1852
1853 void target_execute_cmd(struct se_cmd *cmd)
1854 {
1855 /*
1856 * If the received CDB has aleady been aborted stop processing it here.
1857 */
1858 if (transport_check_aborted_status(cmd, 1))
1859 return;
1860
1861 /*
1862 * Determine if frontend context caller is requesting the stopping of
1863 * this command for frontend exceptions.
1864 */
1865 spin_lock_irq(&cmd->t_state_lock);
1866 if (cmd->transport_state & CMD_T_STOP) {
1867 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1868 __func__, __LINE__, cmd->tag);
1869
1870 spin_unlock_irq(&cmd->t_state_lock);
1871 complete_all(&cmd->t_transport_stop_comp);
1872 return;
1873 }
1874
1875 cmd->t_state = TRANSPORT_PROCESSING;
1876 cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1877 spin_unlock_irq(&cmd->t_state_lock);
1878
1879 if (target_write_prot_action(cmd))
1880 return;
1881
1882 if (target_handle_task_attr(cmd)) {
1883 spin_lock_irq(&cmd->t_state_lock);
1884 cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1885 spin_unlock_irq(&cmd->t_state_lock);
1886 return;
1887 }
1888
1889 __target_execute_cmd(cmd);
1890 }
1891 EXPORT_SYMBOL(target_execute_cmd);
1892
1893 /*
1894 * Process all commands up to the last received ORDERED task attribute which
1895 * requires another blocking boundary
1896 */
1897 static void target_restart_delayed_cmds(struct se_device *dev)
1898 {
1899 for (;;) {
1900 struct se_cmd *cmd;
1901
1902 spin_lock(&dev->delayed_cmd_lock);
1903 if (list_empty(&dev->delayed_cmd_list)) {
1904 spin_unlock(&dev->delayed_cmd_lock);
1905 break;
1906 }
1907
1908 cmd = list_entry(dev->delayed_cmd_list.next,
1909 struct se_cmd, se_delayed_node);
1910 list_del(&cmd->se_delayed_node);
1911 spin_unlock(&dev->delayed_cmd_lock);
1912
1913 __target_execute_cmd(cmd);
1914
1915 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1916 break;
1917 }
1918 }
1919
1920 /*
1921 * Called from I/O completion to determine which dormant/delayed
1922 * and ordered cmds need to have their tasks added to the execution queue.
1923 */
1924 static void transport_complete_task_attr(struct se_cmd *cmd)
1925 {
1926 struct se_device *dev = cmd->se_dev;
1927
1928 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1929 return;
1930
1931 if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1932 atomic_dec_mb(&dev->simple_cmds);
1933 dev->dev_cur_ordered_id++;
1934 pr_debug("Incremented dev->dev_cur_ordered_id: %u for SIMPLE\n",
1935 dev->dev_cur_ordered_id);
1936 } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1937 dev->dev_cur_ordered_id++;
1938 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
1939 dev->dev_cur_ordered_id);
1940 } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1941 atomic_dec_mb(&dev->dev_ordered_sync);
1942
1943 dev->dev_cur_ordered_id++;
1944 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
1945 dev->dev_cur_ordered_id);
1946 }
1947
1948 target_restart_delayed_cmds(dev);
1949 }
1950
1951 static void transport_complete_qf(struct se_cmd *cmd)
1952 {
1953 int ret = 0;
1954
1955 transport_complete_task_attr(cmd);
1956
1957 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1958 trace_target_cmd_complete(cmd);
1959 ret = cmd->se_tfo->queue_status(cmd);
1960 goto out;
1961 }
1962
1963 switch (cmd->data_direction) {
1964 case DMA_FROM_DEVICE:
1965 trace_target_cmd_complete(cmd);
1966 ret = cmd->se_tfo->queue_data_in(cmd);
1967 break;
1968 case DMA_TO_DEVICE:
1969 if (cmd->se_cmd_flags & SCF_BIDI) {
1970 ret = cmd->se_tfo->queue_data_in(cmd);
1971 break;
1972 }
1973 /* Fall through for DMA_TO_DEVICE */
1974 case DMA_NONE:
1975 trace_target_cmd_complete(cmd);
1976 ret = cmd->se_tfo->queue_status(cmd);
1977 break;
1978 default:
1979 break;
1980 }
1981
1982 out:
1983 if (ret < 0) {
1984 transport_handle_queue_full(cmd, cmd->se_dev);
1985 return;
1986 }
1987 transport_lun_remove_cmd(cmd);
1988 transport_cmd_check_stop_to_fabric(cmd);
1989 }
1990
1991 static void transport_handle_queue_full(
1992 struct se_cmd *cmd,
1993 struct se_device *dev)
1994 {
1995 spin_lock_irq(&dev->qf_cmd_lock);
1996 list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1997 atomic_inc_mb(&dev->dev_qf_count);
1998 spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1999
2000 schedule_work(&cmd->se_dev->qf_work_queue);
2001 }
2002
2003 static bool target_read_prot_action(struct se_cmd *cmd)
2004 {
2005 switch (cmd->prot_op) {
2006 case TARGET_PROT_DIN_STRIP:
2007 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2008 u32 sectors = cmd->data_length >>
2009 ilog2(cmd->se_dev->dev_attrib.block_size);
2010
2011 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2012 sectors, 0, cmd->t_prot_sg,
2013 0);
2014 if (cmd->pi_err)
2015 return true;
2016 }
2017 break;
2018 case TARGET_PROT_DIN_INSERT:
2019 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2020 break;
2021
2022 sbc_dif_generate(cmd);
2023 break;
2024 default:
2025 break;
2026 }
2027
2028 return false;
2029 }
2030
2031 static void target_complete_ok_work(struct work_struct *work)
2032 {
2033 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2034 int ret;
2035
2036 /*
2037 * Check if we need to move delayed/dormant tasks from cmds on the
2038 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2039 * Attribute.
2040 */
2041 transport_complete_task_attr(cmd);
2042
2043 /*
2044 * Check to schedule QUEUE_FULL work, or execute an existing
2045 * cmd->transport_qf_callback()
2046 */
2047 if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2048 schedule_work(&cmd->se_dev->qf_work_queue);
2049
2050 /*
2051 * Check if we need to send a sense buffer from
2052 * the struct se_cmd in question.
2053 */
2054 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2055 WARN_ON(!cmd->scsi_status);
2056 ret = transport_send_check_condition_and_sense(
2057 cmd, 0, 1);
2058 if (ret == -EAGAIN || ret == -ENOMEM)
2059 goto queue_full;
2060
2061 transport_lun_remove_cmd(cmd);
2062 transport_cmd_check_stop_to_fabric(cmd);
2063 return;
2064 }
2065 /*
2066 * Check for a callback, used by amongst other things
2067 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2068 */
2069 if (cmd->transport_complete_callback) {
2070 sense_reason_t rc;
2071
2072 rc = cmd->transport_complete_callback(cmd, true);
2073 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
2074 if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2075 !cmd->data_length)
2076 goto queue_rsp;
2077
2078 return;
2079 } else if (rc) {
2080 ret = transport_send_check_condition_and_sense(cmd,
2081 rc, 0);
2082 if (ret == -EAGAIN || ret == -ENOMEM)
2083 goto queue_full;
2084
2085 transport_lun_remove_cmd(cmd);
2086 transport_cmd_check_stop_to_fabric(cmd);
2087 return;
2088 }
2089 }
2090
2091 queue_rsp:
2092 switch (cmd->data_direction) {
2093 case DMA_FROM_DEVICE:
2094 atomic_long_add(cmd->data_length,
2095 &cmd->se_lun->lun_stats.tx_data_octets);
2096 /*
2097 * Perform READ_STRIP of PI using software emulation when
2098 * backend had PI enabled, if the transport will not be
2099 * performing hardware READ_STRIP offload.
2100 */
2101 if (target_read_prot_action(cmd)) {
2102 ret = transport_send_check_condition_and_sense(cmd,
2103 cmd->pi_err, 0);
2104 if (ret == -EAGAIN || ret == -ENOMEM)
2105 goto queue_full;
2106
2107 transport_lun_remove_cmd(cmd);
2108 transport_cmd_check_stop_to_fabric(cmd);
2109 return;
2110 }
2111
2112 trace_target_cmd_complete(cmd);
2113 ret = cmd->se_tfo->queue_data_in(cmd);
2114 if (ret == -EAGAIN || ret == -ENOMEM)
2115 goto queue_full;
2116 break;
2117 case DMA_TO_DEVICE:
2118 atomic_long_add(cmd->data_length,
2119 &cmd->se_lun->lun_stats.rx_data_octets);
2120 /*
2121 * Check if we need to send READ payload for BIDI-COMMAND
2122 */
2123 if (cmd->se_cmd_flags & SCF_BIDI) {
2124 atomic_long_add(cmd->data_length,
2125 &cmd->se_lun->lun_stats.tx_data_octets);
2126 ret = cmd->se_tfo->queue_data_in(cmd);
2127 if (ret == -EAGAIN || ret == -ENOMEM)
2128 goto queue_full;
2129 break;
2130 }
2131 /* Fall through for DMA_TO_DEVICE */
2132 case DMA_NONE:
2133 trace_target_cmd_complete(cmd);
2134 ret = cmd->se_tfo->queue_status(cmd);
2135 if (ret == -EAGAIN || ret == -ENOMEM)
2136 goto queue_full;
2137 break;
2138 default:
2139 break;
2140 }
2141
2142 transport_lun_remove_cmd(cmd);
2143 transport_cmd_check_stop_to_fabric(cmd);
2144 return;
2145
2146 queue_full:
2147 pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2148 " data_direction: %d\n", cmd, cmd->data_direction);
2149 cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2150 transport_handle_queue_full(cmd, cmd->se_dev);
2151 }
2152
2153 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2154 {
2155 struct scatterlist *sg;
2156 int count;
2157
2158 for_each_sg(sgl, sg, nents, count)
2159 __free_page(sg_page(sg));
2160
2161 kfree(sgl);
2162 }
2163
2164 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2165 {
2166 /*
2167 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2168 * emulation, and free + reset pointers if necessary..
2169 */
2170 if (!cmd->t_data_sg_orig)
2171 return;
2172
2173 kfree(cmd->t_data_sg);
2174 cmd->t_data_sg = cmd->t_data_sg_orig;
2175 cmd->t_data_sg_orig = NULL;
2176 cmd->t_data_nents = cmd->t_data_nents_orig;
2177 cmd->t_data_nents_orig = 0;
2178 }
2179
2180 static inline void transport_free_pages(struct se_cmd *cmd)
2181 {
2182 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2183 transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2184 cmd->t_prot_sg = NULL;
2185 cmd->t_prot_nents = 0;
2186 }
2187
2188 if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2189 /*
2190 * Release special case READ buffer payload required for
2191 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2192 */
2193 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2194 transport_free_sgl(cmd->t_bidi_data_sg,
2195 cmd->t_bidi_data_nents);
2196 cmd->t_bidi_data_sg = NULL;
2197 cmd->t_bidi_data_nents = 0;
2198 }
2199 transport_reset_sgl_orig(cmd);
2200 return;
2201 }
2202 transport_reset_sgl_orig(cmd);
2203
2204 transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2205 cmd->t_data_sg = NULL;
2206 cmd->t_data_nents = 0;
2207
2208 transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2209 cmd->t_bidi_data_sg = NULL;
2210 cmd->t_bidi_data_nents = 0;
2211 }
2212
2213 /**
2214 * transport_release_cmd - free a command
2215 * @cmd: command to free
2216 *
2217 * This routine unconditionally frees a command, and reference counting
2218 * or list removal must be done in the caller.
2219 */
2220 static int transport_release_cmd(struct se_cmd *cmd)
2221 {
2222 BUG_ON(!cmd->se_tfo);
2223
2224 if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2225 core_tmr_release_req(cmd->se_tmr_req);
2226 if (cmd->t_task_cdb != cmd->__t_task_cdb)
2227 kfree(cmd->t_task_cdb);
2228 /*
2229 * If this cmd has been setup with target_get_sess_cmd(), drop
2230 * the kref and call ->release_cmd() in kref callback.
2231 */
2232 return target_put_sess_cmd(cmd);
2233 }
2234
2235 /**
2236 * transport_put_cmd - release a reference to a command
2237 * @cmd: command to release
2238 *
2239 * This routine releases our reference to the command and frees it if possible.
2240 */
2241 static int transport_put_cmd(struct se_cmd *cmd)
2242 {
2243 transport_free_pages(cmd);
2244 return transport_release_cmd(cmd);
2245 }
2246
2247 void *transport_kmap_data_sg(struct se_cmd *cmd)
2248 {
2249 struct scatterlist *sg = cmd->t_data_sg;
2250 struct page **pages;
2251 int i;
2252
2253 /*
2254 * We need to take into account a possible offset here for fabrics like
2255 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2256 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2257 */
2258 if (!cmd->t_data_nents)
2259 return NULL;
2260
2261 BUG_ON(!sg);
2262 if (cmd->t_data_nents == 1)
2263 return kmap(sg_page(sg)) + sg->offset;
2264
2265 /* >1 page. use vmap */
2266 pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2267 if (!pages)
2268 return NULL;
2269
2270 /* convert sg[] to pages[] */
2271 for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2272 pages[i] = sg_page(sg);
2273 }
2274
2275 cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
2276 kfree(pages);
2277 if (!cmd->t_data_vmap)
2278 return NULL;
2279
2280 return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2281 }
2282 EXPORT_SYMBOL(transport_kmap_data_sg);
2283
2284 void transport_kunmap_data_sg(struct se_cmd *cmd)
2285 {
2286 if (!cmd->t_data_nents) {
2287 return;
2288 } else if (cmd->t_data_nents == 1) {
2289 kunmap(sg_page(cmd->t_data_sg));
2290 return;
2291 }
2292
2293 vunmap(cmd->t_data_vmap);
2294 cmd->t_data_vmap = NULL;
2295 }
2296 EXPORT_SYMBOL(transport_kunmap_data_sg);
2297
2298 int
2299 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2300 bool zero_page)
2301 {
2302 struct scatterlist *sg;
2303 struct page *page;
2304 gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2305 unsigned int nent;
2306 int i = 0;
2307
2308 nent = DIV_ROUND_UP(length, PAGE_SIZE);
2309 sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2310 if (!sg)
2311 return -ENOMEM;
2312
2313 sg_init_table(sg, nent);
2314
2315 while (length) {
2316 u32 page_len = min_t(u32, length, PAGE_SIZE);
2317 page = alloc_page(GFP_KERNEL | zero_flag);
2318 if (!page)
2319 goto out;
2320
2321 sg_set_page(&sg[i], page, page_len, 0);
2322 length -= page_len;
2323 i++;
2324 }
2325 *sgl = sg;
2326 *nents = nent;
2327 return 0;
2328
2329 out:
2330 while (i > 0) {
2331 i--;
2332 __free_page(sg_page(&sg[i]));
2333 }
2334 kfree(sg);
2335 return -ENOMEM;
2336 }
2337
2338 /*
2339 * Allocate any required resources to execute the command. For writes we
2340 * might not have the payload yet, so notify the fabric via a call to
2341 * ->write_pending instead. Otherwise place it on the execution queue.
2342 */
2343 sense_reason_t
2344 transport_generic_new_cmd(struct se_cmd *cmd)
2345 {
2346 int ret = 0;
2347 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2348
2349 if (cmd->prot_op != TARGET_PROT_NORMAL &&
2350 !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2351 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2352 cmd->prot_length, true);
2353 if (ret < 0)
2354 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2355 }
2356
2357 /*
2358 * Determine is the TCM fabric module has already allocated physical
2359 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2360 * beforehand.
2361 */
2362 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2363 cmd->data_length) {
2364
2365 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2366 (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2367 u32 bidi_length;
2368
2369 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2370 bidi_length = cmd->t_task_nolb *
2371 cmd->se_dev->dev_attrib.block_size;
2372 else
2373 bidi_length = cmd->data_length;
2374
2375 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2376 &cmd->t_bidi_data_nents,
2377 bidi_length, zero_flag);
2378 if (ret < 0)
2379 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2380 }
2381
2382 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2383 cmd->data_length, zero_flag);
2384 if (ret < 0)
2385 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2386 } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2387 cmd->data_length) {
2388 /*
2389 * Special case for COMPARE_AND_WRITE with fabrics
2390 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2391 */
2392 u32 caw_length = cmd->t_task_nolb *
2393 cmd->se_dev->dev_attrib.block_size;
2394
2395 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2396 &cmd->t_bidi_data_nents,
2397 caw_length, zero_flag);
2398 if (ret < 0)
2399 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2400 }
2401 /*
2402 * If this command is not a write we can execute it right here,
2403 * for write buffers we need to notify the fabric driver first
2404 * and let it call back once the write buffers are ready.
2405 */
2406 target_add_to_state_list(cmd);
2407 if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2408 target_execute_cmd(cmd);
2409 return 0;
2410 }
2411 transport_cmd_check_stop(cmd, false, true);
2412
2413 ret = cmd->se_tfo->write_pending(cmd);
2414 if (ret == -EAGAIN || ret == -ENOMEM)
2415 goto queue_full;
2416
2417 /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2418 WARN_ON(ret);
2419
2420 return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2421
2422 queue_full:
2423 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2424 cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2425 transport_handle_queue_full(cmd, cmd->se_dev);
2426 return 0;
2427 }
2428 EXPORT_SYMBOL(transport_generic_new_cmd);
2429
2430 static void transport_write_pending_qf(struct se_cmd *cmd)
2431 {
2432 int ret;
2433
2434 ret = cmd->se_tfo->write_pending(cmd);
2435 if (ret == -EAGAIN || ret == -ENOMEM) {
2436 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2437 cmd);
2438 transport_handle_queue_full(cmd, cmd->se_dev);
2439 }
2440 }
2441
2442 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2443 {
2444 unsigned long flags;
2445 int ret = 0;
2446
2447 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2448 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2449 transport_wait_for_tasks(cmd);
2450
2451 ret = transport_release_cmd(cmd);
2452 } else {
2453 if (wait_for_tasks)
2454 transport_wait_for_tasks(cmd);
2455 /*
2456 * Handle WRITE failure case where transport_generic_new_cmd()
2457 * has already added se_cmd to state_list, but fabric has
2458 * failed command before I/O submission.
2459 */
2460 if (cmd->state_active) {
2461 spin_lock_irqsave(&cmd->t_state_lock, flags);
2462 target_remove_from_state_list(cmd);
2463 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2464 }
2465
2466 if (cmd->se_lun)
2467 transport_lun_remove_cmd(cmd);
2468
2469 ret = transport_put_cmd(cmd);
2470 }
2471 return ret;
2472 }
2473 EXPORT_SYMBOL(transport_generic_free_cmd);
2474
2475 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2476 * @se_cmd: command descriptor to add
2477 * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
2478 */
2479 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2480 {
2481 struct se_session *se_sess = se_cmd->se_sess;
2482 unsigned long flags;
2483 int ret = 0;
2484
2485 /*
2486 * Add a second kref if the fabric caller is expecting to handle
2487 * fabric acknowledgement that requires two target_put_sess_cmd()
2488 * invocations before se_cmd descriptor release.
2489 */
2490 if (ack_kref)
2491 kref_get(&se_cmd->cmd_kref);
2492
2493 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2494 if (se_sess->sess_tearing_down) {
2495 ret = -ESHUTDOWN;
2496 goto out;
2497 }
2498 list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2499 out:
2500 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2501
2502 if (ret && ack_kref)
2503 target_put_sess_cmd(se_cmd);
2504
2505 return ret;
2506 }
2507 EXPORT_SYMBOL(target_get_sess_cmd);
2508
2509 static void target_release_cmd_kref(struct kref *kref)
2510 __releases(&se_cmd->se_sess->sess_cmd_lock)
2511 {
2512 struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2513 struct se_session *se_sess = se_cmd->se_sess;
2514
2515 if (list_empty(&se_cmd->se_cmd_list)) {
2516 spin_unlock(&se_sess->sess_cmd_lock);
2517 se_cmd->se_tfo->release_cmd(se_cmd);
2518 return;
2519 }
2520 if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2521 spin_unlock(&se_sess->sess_cmd_lock);
2522 complete(&se_cmd->cmd_wait_comp);
2523 return;
2524 }
2525 list_del(&se_cmd->se_cmd_list);
2526 spin_unlock(&se_sess->sess_cmd_lock);
2527
2528 se_cmd->se_tfo->release_cmd(se_cmd);
2529 }
2530
2531 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2532 * @se_cmd: command descriptor to drop
2533 */
2534 int target_put_sess_cmd(struct se_cmd *se_cmd)
2535 {
2536 struct se_session *se_sess = se_cmd->se_sess;
2537
2538 if (!se_sess) {
2539 se_cmd->se_tfo->release_cmd(se_cmd);
2540 return 1;
2541 }
2542 return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2543 &se_sess->sess_cmd_lock);
2544 }
2545 EXPORT_SYMBOL(target_put_sess_cmd);
2546
2547 /* target_sess_cmd_list_set_waiting - Flag all commands in
2548 * sess_cmd_list to complete cmd_wait_comp. Set
2549 * sess_tearing_down so no more commands are queued.
2550 * @se_sess: session to flag
2551 */
2552 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2553 {
2554 struct se_cmd *se_cmd;
2555 unsigned long flags;
2556
2557 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2558 if (se_sess->sess_tearing_down) {
2559 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2560 return;
2561 }
2562 se_sess->sess_tearing_down = 1;
2563 list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2564
2565 list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2566 se_cmd->cmd_wait_set = 1;
2567
2568 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2569 }
2570 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2571
2572 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2573 * @se_sess: session to wait for active I/O
2574 */
2575 void target_wait_for_sess_cmds(struct se_session *se_sess)
2576 {
2577 struct se_cmd *se_cmd, *tmp_cmd;
2578 unsigned long flags;
2579
2580 list_for_each_entry_safe(se_cmd, tmp_cmd,
2581 &se_sess->sess_wait_list, se_cmd_list) {
2582 list_del(&se_cmd->se_cmd_list);
2583
2584 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2585 " %d\n", se_cmd, se_cmd->t_state,
2586 se_cmd->se_tfo->get_cmd_state(se_cmd));
2587
2588 wait_for_completion(&se_cmd->cmd_wait_comp);
2589 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2590 " fabric state: %d\n", se_cmd, se_cmd->t_state,
2591 se_cmd->se_tfo->get_cmd_state(se_cmd));
2592
2593 se_cmd->se_tfo->release_cmd(se_cmd);
2594 }
2595
2596 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2597 WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2598 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2599
2600 }
2601 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2602
2603 void transport_clear_lun_ref(struct se_lun *lun)
2604 {
2605 percpu_ref_kill(&lun->lun_ref);
2606 wait_for_completion(&lun->lun_ref_comp);
2607 }
2608
2609 /**
2610 * transport_wait_for_tasks - wait for completion to occur
2611 * @cmd: command to wait
2612 *
2613 * Called from frontend fabric context to wait for storage engine
2614 * to pause and/or release frontend generated struct se_cmd.
2615 */
2616 bool transport_wait_for_tasks(struct se_cmd *cmd)
2617 {
2618 unsigned long flags;
2619
2620 spin_lock_irqsave(&cmd->t_state_lock, flags);
2621 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2622 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2623 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2624 return false;
2625 }
2626
2627 if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2628 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2629 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2630 return false;
2631 }
2632
2633 if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2634 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2635 return false;
2636 }
2637
2638 cmd->transport_state |= CMD_T_STOP;
2639
2640 pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08llx i_state: %d, t_state: %d, CMD_T_STOP\n",
2641 cmd, cmd->tag, cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2642
2643 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2644
2645 wait_for_completion(&cmd->t_transport_stop_comp);
2646
2647 spin_lock_irqsave(&cmd->t_state_lock, flags);
2648 cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2649
2650 pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->t_transport_stop_comp) for ITT: 0x%08llx\n",
2651 cmd->tag);
2652
2653 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2654
2655 return true;
2656 }
2657 EXPORT_SYMBOL(transport_wait_for_tasks);
2658
2659 struct sense_info {
2660 u8 key;
2661 u8 asc;
2662 u8 ascq;
2663 bool add_sector_info;
2664 };
2665
2666 static const struct sense_info sense_info_table[] = {
2667 [TCM_NO_SENSE] = {
2668 .key = NOT_READY
2669 },
2670 [TCM_NON_EXISTENT_LUN] = {
2671 .key = ILLEGAL_REQUEST,
2672 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
2673 },
2674 [TCM_UNSUPPORTED_SCSI_OPCODE] = {
2675 .key = ILLEGAL_REQUEST,
2676 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2677 },
2678 [TCM_SECTOR_COUNT_TOO_MANY] = {
2679 .key = ILLEGAL_REQUEST,
2680 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2681 },
2682 [TCM_UNKNOWN_MODE_PAGE] = {
2683 .key = ILLEGAL_REQUEST,
2684 .asc = 0x24, /* INVALID FIELD IN CDB */
2685 },
2686 [TCM_CHECK_CONDITION_ABORT_CMD] = {
2687 .key = ABORTED_COMMAND,
2688 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
2689 .ascq = 0x03,
2690 },
2691 [TCM_INCORRECT_AMOUNT_OF_DATA] = {
2692 .key = ABORTED_COMMAND,
2693 .asc = 0x0c, /* WRITE ERROR */
2694 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
2695 },
2696 [TCM_INVALID_CDB_FIELD] = {
2697 .key = ILLEGAL_REQUEST,
2698 .asc = 0x24, /* INVALID FIELD IN CDB */
2699 },
2700 [TCM_INVALID_PARAMETER_LIST] = {
2701 .key = ILLEGAL_REQUEST,
2702 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
2703 },
2704 [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
2705 .key = ILLEGAL_REQUEST,
2706 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
2707 },
2708 [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
2709 .key = ILLEGAL_REQUEST,
2710 .asc = 0x0c, /* WRITE ERROR */
2711 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
2712 },
2713 [TCM_SERVICE_CRC_ERROR] = {
2714 .key = ABORTED_COMMAND,
2715 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
2716 .ascq = 0x05, /* N/A */
2717 },
2718 [TCM_SNACK_REJECTED] = {
2719 .key = ABORTED_COMMAND,
2720 .asc = 0x11, /* READ ERROR */
2721 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
2722 },
2723 [TCM_WRITE_PROTECTED] = {
2724 .key = DATA_PROTECT,
2725 .asc = 0x27, /* WRITE PROTECTED */
2726 },
2727 [TCM_ADDRESS_OUT_OF_RANGE] = {
2728 .key = ILLEGAL_REQUEST,
2729 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2730 },
2731 [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
2732 .key = UNIT_ATTENTION,
2733 },
2734 [TCM_CHECK_CONDITION_NOT_READY] = {
2735 .key = NOT_READY,
2736 },
2737 [TCM_MISCOMPARE_VERIFY] = {
2738 .key = MISCOMPARE,
2739 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
2740 .ascq = 0x00,
2741 },
2742 [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
2743 .key = ABORTED_COMMAND,
2744 .asc = 0x10,
2745 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
2746 .add_sector_info = true,
2747 },
2748 [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
2749 .key = ABORTED_COMMAND,
2750 .asc = 0x10,
2751 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2752 .add_sector_info = true,
2753 },
2754 [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
2755 .key = ABORTED_COMMAND,
2756 .asc = 0x10,
2757 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2758 .add_sector_info = true,
2759 },
2760 [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
2761 /*
2762 * Returning ILLEGAL REQUEST would cause immediate IO errors on
2763 * Solaris initiators. Returning NOT READY instead means the
2764 * operations will be retried a finite number of times and we
2765 * can survive intermittent errors.
2766 */
2767 .key = NOT_READY,
2768 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
2769 },
2770 };
2771
2772 static int translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
2773 {
2774 const struct sense_info *si;
2775 u8 *buffer = cmd->sense_buffer;
2776 int r = (__force int)reason;
2777 u8 asc, ascq;
2778 bool desc_format = target_sense_desc_format(cmd->se_dev);
2779
2780 if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
2781 si = &sense_info_table[r];
2782 else
2783 si = &sense_info_table[(__force int)
2784 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
2785
2786 if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
2787 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2788 WARN_ON_ONCE(asc == 0);
2789 } else if (si->asc == 0) {
2790 WARN_ON_ONCE(cmd->scsi_asc == 0);
2791 asc = cmd->scsi_asc;
2792 ascq = cmd->scsi_ascq;
2793 } else {
2794 asc = si->asc;
2795 ascq = si->ascq;
2796 }
2797
2798 scsi_build_sense_buffer(desc_format, buffer, si->key, asc, ascq);
2799 if (si->add_sector_info)
2800 return scsi_set_sense_information(buffer,
2801 cmd->scsi_sense_length,
2802 cmd->bad_sector);
2803
2804 return 0;
2805 }
2806
2807 int
2808 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2809 sense_reason_t reason, int from_transport)
2810 {
2811 unsigned long flags;
2812
2813 spin_lock_irqsave(&cmd->t_state_lock, flags);
2814 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2815 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2816 return 0;
2817 }
2818 cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2819 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2820
2821 if (!from_transport) {
2822 int rc;
2823
2824 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2825 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2826 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
2827 rc = translate_sense_reason(cmd, reason);
2828 if (rc)
2829 return rc;
2830 }
2831
2832 trace_target_cmd_complete(cmd);
2833 return cmd->se_tfo->queue_status(cmd);
2834 }
2835 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2836
2837 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2838 {
2839 if (!(cmd->transport_state & CMD_T_ABORTED))
2840 return 0;
2841
2842 /*
2843 * If cmd has been aborted but either no status is to be sent or it has
2844 * already been sent, just return
2845 */
2846 if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
2847 return 1;
2848
2849 pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08llx\n",
2850 cmd->t_task_cdb[0], cmd->tag);
2851
2852 cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2853 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2854 trace_target_cmd_complete(cmd);
2855 cmd->se_tfo->queue_status(cmd);
2856
2857 return 1;
2858 }
2859 EXPORT_SYMBOL(transport_check_aborted_status);
2860
2861 void transport_send_task_abort(struct se_cmd *cmd)
2862 {
2863 unsigned long flags;
2864
2865 spin_lock_irqsave(&cmd->t_state_lock, flags);
2866 if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2867 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2868 return;
2869 }
2870 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2871
2872 /*
2873 * If there are still expected incoming fabric WRITEs, we wait
2874 * until until they have completed before sending a TASK_ABORTED
2875 * response. This response with TASK_ABORTED status will be
2876 * queued back to fabric module by transport_check_aborted_status().
2877 */
2878 if (cmd->data_direction == DMA_TO_DEVICE) {
2879 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2880 cmd->transport_state |= CMD_T_ABORTED;
2881 cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2882 return;
2883 }
2884 }
2885 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2886
2887 transport_lun_remove_cmd(cmd);
2888
2889 pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
2890 cmd->t_task_cdb[0], cmd->tag);
2891
2892 trace_target_cmd_complete(cmd);
2893 cmd->se_tfo->queue_status(cmd);
2894 }
2895
2896 static void target_tmr_work(struct work_struct *work)
2897 {
2898 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2899 struct se_device *dev = cmd->se_dev;
2900 struct se_tmr_req *tmr = cmd->se_tmr_req;
2901 int ret;
2902
2903 switch (tmr->function) {
2904 case TMR_ABORT_TASK:
2905 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2906 break;
2907 case TMR_ABORT_TASK_SET:
2908 case TMR_CLEAR_ACA:
2909 case TMR_CLEAR_TASK_SET:
2910 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2911 break;
2912 case TMR_LUN_RESET:
2913 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2914 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2915 TMR_FUNCTION_REJECTED;
2916 if (tmr->response == TMR_FUNCTION_COMPLETE) {
2917 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
2918 cmd->orig_fe_lun, 0x29,
2919 ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
2920 }
2921 break;
2922 case TMR_TARGET_WARM_RESET:
2923 tmr->response = TMR_FUNCTION_REJECTED;
2924 break;
2925 case TMR_TARGET_COLD_RESET:
2926 tmr->response = TMR_FUNCTION_REJECTED;
2927 break;
2928 default:
2929 pr_err("Uknown TMR function: 0x%02x.\n",
2930 tmr->function);
2931 tmr->response = TMR_FUNCTION_REJECTED;
2932 break;
2933 }
2934
2935 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2936 cmd->se_tfo->queue_tm_rsp(cmd);
2937
2938 transport_cmd_check_stop_to_fabric(cmd);
2939 }
2940
2941 int transport_generic_handle_tmr(
2942 struct se_cmd *cmd)
2943 {
2944 unsigned long flags;
2945
2946 spin_lock_irqsave(&cmd->t_state_lock, flags);
2947 cmd->transport_state |= CMD_T_ACTIVE;
2948 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2949
2950 INIT_WORK(&cmd->work, target_tmr_work);
2951 queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2952 return 0;
2953 }
2954 EXPORT_SYMBOL(transport_generic_handle_tmr);
2955
2956 bool
2957 target_check_wce(struct se_device *dev)
2958 {
2959 bool wce = false;
2960
2961 if (dev->transport->get_write_cache)
2962 wce = dev->transport->get_write_cache(dev);
2963 else if (dev->dev_attrib.emulate_write_cache > 0)
2964 wce = true;
2965
2966 return wce;
2967 }
2968
2969 bool
2970 target_check_fua(struct se_device *dev)
2971 {
2972 return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
2973 }
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