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numa: fix /proc/<pid>/numa_maps for hugetlbfs on s390
[deliverable/linux.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
345 spin_lock_irq(&se_nacl->nacl_sess_lock);
346 /*
347 * The se_nacl->nacl_sess pointer will be set to the
348 * last active I_T Nexus for each struct se_node_acl.
349 */
350 se_nacl->nacl_sess = se_sess;
351
352 list_add_tail(&se_sess->sess_acl_list,
353 &se_nacl->acl_sess_list);
354 spin_unlock_irq(&se_nacl->nacl_sess_lock);
355 }
356 list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
357
358 pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
359 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
360 }
361 EXPORT_SYMBOL(__transport_register_session);
362
363 void transport_register_session(
364 struct se_portal_group *se_tpg,
365 struct se_node_acl *se_nacl,
366 struct se_session *se_sess,
367 void *fabric_sess_ptr)
368 {
369 unsigned long flags;
370
371 spin_lock_irqsave(&se_tpg->session_lock, flags);
372 __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
373 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
374 }
375 EXPORT_SYMBOL(transport_register_session);
376
377 static void target_release_session(struct kref *kref)
378 {
379 struct se_session *se_sess = container_of(kref,
380 struct se_session, sess_kref);
381 struct se_portal_group *se_tpg = se_sess->se_tpg;
382
383 se_tpg->se_tpg_tfo->close_session(se_sess);
384 }
385
386 int target_get_session(struct se_session *se_sess)
387 {
388 return kref_get_unless_zero(&se_sess->sess_kref);
389 }
390 EXPORT_SYMBOL(target_get_session);
391
392 void target_put_session(struct se_session *se_sess)
393 {
394 kref_put(&se_sess->sess_kref, target_release_session);
395 }
396 EXPORT_SYMBOL(target_put_session);
397
398 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
399 {
400 struct se_session *se_sess;
401 ssize_t len = 0;
402
403 spin_lock_bh(&se_tpg->session_lock);
404 list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
405 if (!se_sess->se_node_acl)
406 continue;
407 if (!se_sess->se_node_acl->dynamic_node_acl)
408 continue;
409 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
410 break;
411
412 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
413 se_sess->se_node_acl->initiatorname);
414 len += 1; /* Include NULL terminator */
415 }
416 spin_unlock_bh(&se_tpg->session_lock);
417
418 return len;
419 }
420 EXPORT_SYMBOL(target_show_dynamic_sessions);
421
422 static void target_complete_nacl(struct kref *kref)
423 {
424 struct se_node_acl *nacl = container_of(kref,
425 struct se_node_acl, acl_kref);
426
427 complete(&nacl->acl_free_comp);
428 }
429
430 void target_put_nacl(struct se_node_acl *nacl)
431 {
432 kref_put(&nacl->acl_kref, target_complete_nacl);
433 }
434 EXPORT_SYMBOL(target_put_nacl);
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 struct se_node_acl *se_nacl = se_sess->se_node_acl;
468 /*
469 * Drop the se_node_acl->nacl_kref obtained from within
470 * core_tpg_get_initiator_node_acl().
471 */
472 if (se_nacl) {
473 se_sess->se_node_acl = NULL;
474 target_put_nacl(se_nacl);
475 }
476 if (se_sess->sess_cmd_map) {
477 percpu_ida_destroy(&se_sess->sess_tag_pool);
478 kvfree(se_sess->sess_cmd_map);
479 }
480 kmem_cache_free(se_sess_cache, se_sess);
481 }
482 EXPORT_SYMBOL(transport_free_session);
483
484 void transport_deregister_session(struct se_session *se_sess)
485 {
486 struct se_portal_group *se_tpg = se_sess->se_tpg;
487 const struct target_core_fabric_ops *se_tfo;
488 struct se_node_acl *se_nacl;
489 unsigned long flags;
490 bool drop_nacl = false;
491
492 if (!se_tpg) {
493 transport_free_session(se_sess);
494 return;
495 }
496 se_tfo = se_tpg->se_tpg_tfo;
497
498 spin_lock_irqsave(&se_tpg->session_lock, flags);
499 list_del(&se_sess->sess_list);
500 se_sess->se_tpg = NULL;
501 se_sess->fabric_sess_ptr = NULL;
502 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
503
504 /*
505 * Determine if we need to do extra work for this initiator node's
506 * struct se_node_acl if it had been previously dynamically generated.
507 */
508 se_nacl = se_sess->se_node_acl;
509
510 mutex_lock(&se_tpg->acl_node_mutex);
511 if (se_nacl && se_nacl->dynamic_node_acl) {
512 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
513 list_del(&se_nacl->acl_list);
514 drop_nacl = true;
515 }
516 }
517 mutex_unlock(&se_tpg->acl_node_mutex);
518
519 if (drop_nacl) {
520 core_tpg_wait_for_nacl_pr_ref(se_nacl);
521 core_free_device_list_for_node(se_nacl, se_tpg);
522 se_sess->se_node_acl = NULL;
523 kfree(se_nacl);
524 }
525 pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
526 se_tpg->se_tpg_tfo->get_fabric_name());
527 /*
528 * If last kref is dropping now for an explicit NodeACL, awake sleeping
529 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
530 * removal context from within transport_free_session() code.
531 */
532
533 transport_free_session(se_sess);
534 }
535 EXPORT_SYMBOL(transport_deregister_session);
536
537 /*
538 * Called with cmd->t_state_lock held.
539 */
540 static void target_remove_from_state_list(struct se_cmd *cmd)
541 {
542 struct se_device *dev = cmd->se_dev;
543 unsigned long flags;
544
545 if (!dev)
546 return;
547
548 if (cmd->transport_state & CMD_T_BUSY)
549 return;
550
551 spin_lock_irqsave(&dev->execute_task_lock, flags);
552 if (cmd->state_active) {
553 list_del(&cmd->state_list);
554 cmd->state_active = false;
555 }
556 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
557 }
558
559 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
560 bool write_pending)
561 {
562 unsigned long flags;
563
564 spin_lock_irqsave(&cmd->t_state_lock, flags);
565 if (write_pending)
566 cmd->t_state = TRANSPORT_WRITE_PENDING;
567
568 if (remove_from_lists) {
569 target_remove_from_state_list(cmd);
570
571 /*
572 * Clear struct se_cmd->se_lun before the handoff to FE.
573 */
574 cmd->se_lun = NULL;
575 }
576
577 /*
578 * Determine if frontend context caller is requesting the stopping of
579 * this command for frontend exceptions.
580 */
581 if (cmd->transport_state & CMD_T_STOP) {
582 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
583 __func__, __LINE__, cmd->tag);
584
585 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
586
587 complete_all(&cmd->t_transport_stop_comp);
588 return 1;
589 }
590
591 cmd->transport_state &= ~CMD_T_ACTIVE;
592 if (remove_from_lists) {
593 /*
594 * Some fabric modules like tcm_loop can release
595 * their internally allocated I/O reference now and
596 * struct se_cmd now.
597 *
598 * Fabric modules are expected to return '1' here if the
599 * se_cmd being passed is released at this point,
600 * or zero if not being released.
601 */
602 if (cmd->se_tfo->check_stop_free != NULL) {
603 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
604 return cmd->se_tfo->check_stop_free(cmd);
605 }
606 }
607
608 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
609 return 0;
610 }
611
612 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
613 {
614 return transport_cmd_check_stop(cmd, true, false);
615 }
616
617 static void transport_lun_remove_cmd(struct se_cmd *cmd)
618 {
619 struct se_lun *lun = cmd->se_lun;
620
621 if (!lun)
622 return;
623
624 if (cmpxchg(&cmd->lun_ref_active, true, false))
625 percpu_ref_put(&lun->lun_ref);
626 }
627
628 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
629 {
630 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
631 transport_lun_remove_cmd(cmd);
632 /*
633 * Allow the fabric driver to unmap any resources before
634 * releasing the descriptor via TFO->release_cmd()
635 */
636 if (remove)
637 cmd->se_tfo->aborted_task(cmd);
638
639 if (transport_cmd_check_stop_to_fabric(cmd))
640 return;
641 if (remove)
642 transport_put_cmd(cmd);
643 }
644
645 static void target_complete_failure_work(struct work_struct *work)
646 {
647 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
648
649 transport_generic_request_failure(cmd,
650 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
651 }
652
653 /*
654 * Used when asking transport to copy Sense Data from the underlying
655 * Linux/SCSI struct scsi_cmnd
656 */
657 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
658 {
659 struct se_device *dev = cmd->se_dev;
660
661 WARN_ON(!cmd->se_lun);
662
663 if (!dev)
664 return NULL;
665
666 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
667 return NULL;
668
669 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
670
671 pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
672 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
673 return cmd->sense_buffer;
674 }
675
676 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
677 {
678 struct se_device *dev = cmd->se_dev;
679 int success = scsi_status == GOOD;
680 unsigned long flags;
681
682 cmd->scsi_status = scsi_status;
683
684
685 spin_lock_irqsave(&cmd->t_state_lock, flags);
686 cmd->transport_state &= ~CMD_T_BUSY;
687
688 if (dev && dev->transport->transport_complete) {
689 dev->transport->transport_complete(cmd,
690 cmd->t_data_sg,
691 transport_get_sense_buffer(cmd));
692 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
693 success = 1;
694 }
695
696 /*
697 * See if we are waiting to complete for an exception condition.
698 */
699 if (cmd->transport_state & CMD_T_REQUEST_STOP) {
700 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
701 complete(&cmd->task_stop_comp);
702 return;
703 }
704
705 /*
706 * Check for case where an explicit ABORT_TASK has been received
707 * and transport_wait_for_tasks() will be waiting for completion..
708 */
709 if (cmd->transport_state & CMD_T_ABORTED &&
710 cmd->transport_state & CMD_T_STOP) {
711 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
712 complete_all(&cmd->t_transport_stop_comp);
713 return;
714 } else if (!success) {
715 INIT_WORK(&cmd->work, target_complete_failure_work);
716 } else {
717 INIT_WORK(&cmd->work, target_complete_ok_work);
718 }
719
720 cmd->t_state = TRANSPORT_COMPLETE;
721 cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
722 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
723
724 if (cmd->cpuid == -1)
725 queue_work(target_completion_wq, &cmd->work);
726 else
727 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
728 }
729 EXPORT_SYMBOL(target_complete_cmd);
730
731 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
732 {
733 if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
734 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
735 cmd->residual_count += cmd->data_length - length;
736 } else {
737 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
738 cmd->residual_count = cmd->data_length - length;
739 }
740
741 cmd->data_length = length;
742 }
743
744 target_complete_cmd(cmd, scsi_status);
745 }
746 EXPORT_SYMBOL(target_complete_cmd_with_length);
747
748 static void target_add_to_state_list(struct se_cmd *cmd)
749 {
750 struct se_device *dev = cmd->se_dev;
751 unsigned long flags;
752
753 spin_lock_irqsave(&dev->execute_task_lock, flags);
754 if (!cmd->state_active) {
755 list_add_tail(&cmd->state_list, &dev->state_list);
756 cmd->state_active = true;
757 }
758 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
759 }
760
761 /*
762 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
763 */
764 static void transport_write_pending_qf(struct se_cmd *cmd);
765 static void transport_complete_qf(struct se_cmd *cmd);
766
767 void target_qf_do_work(struct work_struct *work)
768 {
769 struct se_device *dev = container_of(work, struct se_device,
770 qf_work_queue);
771 LIST_HEAD(qf_cmd_list);
772 struct se_cmd *cmd, *cmd_tmp;
773
774 spin_lock_irq(&dev->qf_cmd_lock);
775 list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
776 spin_unlock_irq(&dev->qf_cmd_lock);
777
778 list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
779 list_del(&cmd->se_qf_node);
780 atomic_dec_mb(&dev->dev_qf_count);
781
782 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
783 " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
784 (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
785 (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
786 : "UNKNOWN");
787
788 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
789 transport_write_pending_qf(cmd);
790 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
791 transport_complete_qf(cmd);
792 }
793 }
794
795 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
796 {
797 switch (cmd->data_direction) {
798 case DMA_NONE:
799 return "NONE";
800 case DMA_FROM_DEVICE:
801 return "READ";
802 case DMA_TO_DEVICE:
803 return "WRITE";
804 case DMA_BIDIRECTIONAL:
805 return "BIDI";
806 default:
807 break;
808 }
809
810 return "UNKNOWN";
811 }
812
813 void transport_dump_dev_state(
814 struct se_device *dev,
815 char *b,
816 int *bl)
817 {
818 *bl += sprintf(b + *bl, "Status: ");
819 if (dev->export_count)
820 *bl += sprintf(b + *bl, "ACTIVATED");
821 else
822 *bl += sprintf(b + *bl, "DEACTIVATED");
823
824 *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
825 *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
826 dev->dev_attrib.block_size,
827 dev->dev_attrib.hw_max_sectors);
828 *bl += sprintf(b + *bl, " ");
829 }
830
831 void transport_dump_vpd_proto_id(
832 struct t10_vpd *vpd,
833 unsigned char *p_buf,
834 int p_buf_len)
835 {
836 unsigned char buf[VPD_TMP_BUF_SIZE];
837 int len;
838
839 memset(buf, 0, VPD_TMP_BUF_SIZE);
840 len = sprintf(buf, "T10 VPD Protocol Identifier: ");
841
842 switch (vpd->protocol_identifier) {
843 case 0x00:
844 sprintf(buf+len, "Fibre Channel\n");
845 break;
846 case 0x10:
847 sprintf(buf+len, "Parallel SCSI\n");
848 break;
849 case 0x20:
850 sprintf(buf+len, "SSA\n");
851 break;
852 case 0x30:
853 sprintf(buf+len, "IEEE 1394\n");
854 break;
855 case 0x40:
856 sprintf(buf+len, "SCSI Remote Direct Memory Access"
857 " Protocol\n");
858 break;
859 case 0x50:
860 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
861 break;
862 case 0x60:
863 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
864 break;
865 case 0x70:
866 sprintf(buf+len, "Automation/Drive Interface Transport"
867 " Protocol\n");
868 break;
869 case 0x80:
870 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
871 break;
872 default:
873 sprintf(buf+len, "Unknown 0x%02x\n",
874 vpd->protocol_identifier);
875 break;
876 }
877
878 if (p_buf)
879 strncpy(p_buf, buf, p_buf_len);
880 else
881 pr_debug("%s", buf);
882 }
883
884 void
885 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
886 {
887 /*
888 * Check if the Protocol Identifier Valid (PIV) bit is set..
889 *
890 * from spc3r23.pdf section 7.5.1
891 */
892 if (page_83[1] & 0x80) {
893 vpd->protocol_identifier = (page_83[0] & 0xf0);
894 vpd->protocol_identifier_set = 1;
895 transport_dump_vpd_proto_id(vpd, NULL, 0);
896 }
897 }
898 EXPORT_SYMBOL(transport_set_vpd_proto_id);
899
900 int transport_dump_vpd_assoc(
901 struct t10_vpd *vpd,
902 unsigned char *p_buf,
903 int p_buf_len)
904 {
905 unsigned char buf[VPD_TMP_BUF_SIZE];
906 int ret = 0;
907 int len;
908
909 memset(buf, 0, VPD_TMP_BUF_SIZE);
910 len = sprintf(buf, "T10 VPD Identifier Association: ");
911
912 switch (vpd->association) {
913 case 0x00:
914 sprintf(buf+len, "addressed logical unit\n");
915 break;
916 case 0x10:
917 sprintf(buf+len, "target port\n");
918 break;
919 case 0x20:
920 sprintf(buf+len, "SCSI target device\n");
921 break;
922 default:
923 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
924 ret = -EINVAL;
925 break;
926 }
927
928 if (p_buf)
929 strncpy(p_buf, buf, p_buf_len);
930 else
931 pr_debug("%s", buf);
932
933 return ret;
934 }
935
936 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
937 {
938 /*
939 * The VPD identification association..
940 *
941 * from spc3r23.pdf Section 7.6.3.1 Table 297
942 */
943 vpd->association = (page_83[1] & 0x30);
944 return transport_dump_vpd_assoc(vpd, NULL, 0);
945 }
946 EXPORT_SYMBOL(transport_set_vpd_assoc);
947
948 int transport_dump_vpd_ident_type(
949 struct t10_vpd *vpd,
950 unsigned char *p_buf,
951 int p_buf_len)
952 {
953 unsigned char buf[VPD_TMP_BUF_SIZE];
954 int ret = 0;
955 int len;
956
957 memset(buf, 0, VPD_TMP_BUF_SIZE);
958 len = sprintf(buf, "T10 VPD Identifier Type: ");
959
960 switch (vpd->device_identifier_type) {
961 case 0x00:
962 sprintf(buf+len, "Vendor specific\n");
963 break;
964 case 0x01:
965 sprintf(buf+len, "T10 Vendor ID based\n");
966 break;
967 case 0x02:
968 sprintf(buf+len, "EUI-64 based\n");
969 break;
970 case 0x03:
971 sprintf(buf+len, "NAA\n");
972 break;
973 case 0x04:
974 sprintf(buf+len, "Relative target port identifier\n");
975 break;
976 case 0x08:
977 sprintf(buf+len, "SCSI name string\n");
978 break;
979 default:
980 sprintf(buf+len, "Unsupported: 0x%02x\n",
981 vpd->device_identifier_type);
982 ret = -EINVAL;
983 break;
984 }
985
986 if (p_buf) {
987 if (p_buf_len < strlen(buf)+1)
988 return -EINVAL;
989 strncpy(p_buf, buf, p_buf_len);
990 } else {
991 pr_debug("%s", buf);
992 }
993
994 return ret;
995 }
996
997 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
998 {
999 /*
1000 * The VPD identifier type..
1001 *
1002 * from spc3r23.pdf Section 7.6.3.1 Table 298
1003 */
1004 vpd->device_identifier_type = (page_83[1] & 0x0f);
1005 return transport_dump_vpd_ident_type(vpd, NULL, 0);
1006 }
1007 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1008
1009 int transport_dump_vpd_ident(
1010 struct t10_vpd *vpd,
1011 unsigned char *p_buf,
1012 int p_buf_len)
1013 {
1014 unsigned char buf[VPD_TMP_BUF_SIZE];
1015 int ret = 0;
1016
1017 memset(buf, 0, VPD_TMP_BUF_SIZE);
1018
1019 switch (vpd->device_identifier_code_set) {
1020 case 0x01: /* Binary */
1021 snprintf(buf, sizeof(buf),
1022 "T10 VPD Binary Device Identifier: %s\n",
1023 &vpd->device_identifier[0]);
1024 break;
1025 case 0x02: /* ASCII */
1026 snprintf(buf, sizeof(buf),
1027 "T10 VPD ASCII Device Identifier: %s\n",
1028 &vpd->device_identifier[0]);
1029 break;
1030 case 0x03: /* UTF-8 */
1031 snprintf(buf, sizeof(buf),
1032 "T10 VPD UTF-8 Device Identifier: %s\n",
1033 &vpd->device_identifier[0]);
1034 break;
1035 default:
1036 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1037 " 0x%02x", vpd->device_identifier_code_set);
1038 ret = -EINVAL;
1039 break;
1040 }
1041
1042 if (p_buf)
1043 strncpy(p_buf, buf, p_buf_len);
1044 else
1045 pr_debug("%s", buf);
1046
1047 return ret;
1048 }
1049
1050 int
1051 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1052 {
1053 static const char hex_str[] = "0123456789abcdef";
1054 int j = 0, i = 4; /* offset to start of the identifier */
1055
1056 /*
1057 * The VPD Code Set (encoding)
1058 *
1059 * from spc3r23.pdf Section 7.6.3.1 Table 296
1060 */
1061 vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1062 switch (vpd->device_identifier_code_set) {
1063 case 0x01: /* Binary */
1064 vpd->device_identifier[j++] =
1065 hex_str[vpd->device_identifier_type];
1066 while (i < (4 + page_83[3])) {
1067 vpd->device_identifier[j++] =
1068 hex_str[(page_83[i] & 0xf0) >> 4];
1069 vpd->device_identifier[j++] =
1070 hex_str[page_83[i] & 0x0f];
1071 i++;
1072 }
1073 break;
1074 case 0x02: /* ASCII */
1075 case 0x03: /* UTF-8 */
1076 while (i < (4 + page_83[3]))
1077 vpd->device_identifier[j++] = page_83[i++];
1078 break;
1079 default:
1080 break;
1081 }
1082
1083 return transport_dump_vpd_ident(vpd, NULL, 0);
1084 }
1085 EXPORT_SYMBOL(transport_set_vpd_ident);
1086
1087 static sense_reason_t
1088 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1089 unsigned int size)
1090 {
1091 u32 mtl;
1092
1093 if (!cmd->se_tfo->max_data_sg_nents)
1094 return TCM_NO_SENSE;
1095 /*
1096 * Check if fabric enforced maximum SGL entries per I/O descriptor
1097 * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT +
1098 * residual_count and reduce original cmd->data_length to maximum
1099 * length based on single PAGE_SIZE entry scatter-lists.
1100 */
1101 mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1102 if (cmd->data_length > mtl) {
1103 /*
1104 * If an existing CDB overflow is present, calculate new residual
1105 * based on CDB size minus fabric maximum transfer length.
1106 *
1107 * If an existing CDB underflow is present, calculate new residual
1108 * based on original cmd->data_length minus fabric maximum transfer
1109 * length.
1110 *
1111 * Otherwise, set the underflow residual based on cmd->data_length
1112 * minus fabric maximum transfer length.
1113 */
1114 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1115 cmd->residual_count = (size - mtl);
1116 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1117 u32 orig_dl = size + cmd->residual_count;
1118 cmd->residual_count = (orig_dl - mtl);
1119 } else {
1120 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1121 cmd->residual_count = (cmd->data_length - mtl);
1122 }
1123 cmd->data_length = mtl;
1124 /*
1125 * Reset sbc_check_prot() calculated protection payload
1126 * length based upon the new smaller MTL.
1127 */
1128 if (cmd->prot_length) {
1129 u32 sectors = (mtl / dev->dev_attrib.block_size);
1130 cmd->prot_length = dev->prot_length * sectors;
1131 }
1132 }
1133 return TCM_NO_SENSE;
1134 }
1135
1136 sense_reason_t
1137 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1138 {
1139 struct se_device *dev = cmd->se_dev;
1140
1141 if (cmd->unknown_data_length) {
1142 cmd->data_length = size;
1143 } else if (size != cmd->data_length) {
1144 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1145 " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1146 " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1147 cmd->data_length, size, cmd->t_task_cdb[0]);
1148
1149 if (cmd->data_direction == DMA_TO_DEVICE &&
1150 cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1151 pr_err("Rejecting underflow/overflow WRITE data\n");
1152 return TCM_INVALID_CDB_FIELD;
1153 }
1154 /*
1155 * Reject READ_* or WRITE_* with overflow/underflow for
1156 * type SCF_SCSI_DATA_CDB.
1157 */
1158 if (dev->dev_attrib.block_size != 512) {
1159 pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1160 " CDB on non 512-byte sector setup subsystem"
1161 " plugin: %s\n", dev->transport->name);
1162 /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1163 return TCM_INVALID_CDB_FIELD;
1164 }
1165 /*
1166 * For the overflow case keep the existing fabric provided
1167 * ->data_length. Otherwise for the underflow case, reset
1168 * ->data_length to the smaller SCSI expected data transfer
1169 * length.
1170 */
1171 if (size > cmd->data_length) {
1172 cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1173 cmd->residual_count = (size - cmd->data_length);
1174 } else {
1175 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1176 cmd->residual_count = (cmd->data_length - size);
1177 cmd->data_length = size;
1178 }
1179 }
1180
1181 return target_check_max_data_sg_nents(cmd, dev, size);
1182
1183 }
1184
1185 /*
1186 * Used by fabric modules containing a local struct se_cmd within their
1187 * fabric dependent per I/O descriptor.
1188 *
1189 * Preserves the value of @cmd->tag.
1190 */
1191 void transport_init_se_cmd(
1192 struct se_cmd *cmd,
1193 const struct target_core_fabric_ops *tfo,
1194 struct se_session *se_sess,
1195 u32 data_length,
1196 int data_direction,
1197 int task_attr,
1198 unsigned char *sense_buffer)
1199 {
1200 INIT_LIST_HEAD(&cmd->se_delayed_node);
1201 INIT_LIST_HEAD(&cmd->se_qf_node);
1202 INIT_LIST_HEAD(&cmd->se_cmd_list);
1203 INIT_LIST_HEAD(&cmd->state_list);
1204 init_completion(&cmd->t_transport_stop_comp);
1205 init_completion(&cmd->cmd_wait_comp);
1206 init_completion(&cmd->task_stop_comp);
1207 spin_lock_init(&cmd->t_state_lock);
1208 kref_init(&cmd->cmd_kref);
1209 cmd->transport_state = CMD_T_DEV_ACTIVE;
1210
1211 cmd->se_tfo = tfo;
1212 cmd->se_sess = se_sess;
1213 cmd->data_length = data_length;
1214 cmd->data_direction = data_direction;
1215 cmd->sam_task_attr = task_attr;
1216 cmd->sense_buffer = sense_buffer;
1217
1218 cmd->state_active = false;
1219 }
1220 EXPORT_SYMBOL(transport_init_se_cmd);
1221
1222 static sense_reason_t
1223 transport_check_alloc_task_attr(struct se_cmd *cmd)
1224 {
1225 struct se_device *dev = cmd->se_dev;
1226
1227 /*
1228 * Check if SAM Task Attribute emulation is enabled for this
1229 * struct se_device storage object
1230 */
1231 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1232 return 0;
1233
1234 if (cmd->sam_task_attr == TCM_ACA_TAG) {
1235 pr_debug("SAM Task Attribute ACA"
1236 " emulation is not supported\n");
1237 return TCM_INVALID_CDB_FIELD;
1238 }
1239
1240 return 0;
1241 }
1242
1243 sense_reason_t
1244 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1245 {
1246 struct se_device *dev = cmd->se_dev;
1247 sense_reason_t ret;
1248
1249 /*
1250 * Ensure that the received CDB is less than the max (252 + 8) bytes
1251 * for VARIABLE_LENGTH_CMD
1252 */
1253 if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1254 pr_err("Received SCSI CDB with command_size: %d that"
1255 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1256 scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1257 return TCM_INVALID_CDB_FIELD;
1258 }
1259 /*
1260 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1261 * allocate the additional extended CDB buffer now.. Otherwise
1262 * setup the pointer from __t_task_cdb to t_task_cdb.
1263 */
1264 if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1265 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1266 GFP_KERNEL);
1267 if (!cmd->t_task_cdb) {
1268 pr_err("Unable to allocate cmd->t_task_cdb"
1269 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1270 scsi_command_size(cdb),
1271 (unsigned long)sizeof(cmd->__t_task_cdb));
1272 return TCM_OUT_OF_RESOURCES;
1273 }
1274 } else
1275 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1276 /*
1277 * Copy the original CDB into cmd->
1278 */
1279 memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1280
1281 trace_target_sequencer_start(cmd);
1282
1283 /*
1284 * Check for an existing UNIT ATTENTION condition
1285 */
1286 ret = target_scsi3_ua_check(cmd);
1287 if (ret)
1288 return ret;
1289
1290 ret = target_alua_state_check(cmd);
1291 if (ret)
1292 return ret;
1293
1294 ret = target_check_reservation(cmd);
1295 if (ret) {
1296 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1297 return ret;
1298 }
1299
1300 ret = dev->transport->parse_cdb(cmd);
1301 if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1302 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1303 cmd->se_tfo->get_fabric_name(),
1304 cmd->se_sess->se_node_acl->initiatorname,
1305 cmd->t_task_cdb[0]);
1306 if (ret)
1307 return ret;
1308
1309 ret = transport_check_alloc_task_attr(cmd);
1310 if (ret)
1311 return ret;
1312
1313 cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1314 atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1315 return 0;
1316 }
1317 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1318
1319 /*
1320 * Used by fabric module frontends to queue tasks directly.
1321 * May only be used from process context.
1322 */
1323 int transport_handle_cdb_direct(
1324 struct se_cmd *cmd)
1325 {
1326 sense_reason_t ret;
1327
1328 if (!cmd->se_lun) {
1329 dump_stack();
1330 pr_err("cmd->se_lun is NULL\n");
1331 return -EINVAL;
1332 }
1333 if (in_interrupt()) {
1334 dump_stack();
1335 pr_err("transport_generic_handle_cdb cannot be called"
1336 " from interrupt context\n");
1337 return -EINVAL;
1338 }
1339 /*
1340 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1341 * outstanding descriptors are handled correctly during shutdown via
1342 * transport_wait_for_tasks()
1343 *
1344 * Also, we don't take cmd->t_state_lock here as we only expect
1345 * this to be called for initial descriptor submission.
1346 */
1347 cmd->t_state = TRANSPORT_NEW_CMD;
1348 cmd->transport_state |= CMD_T_ACTIVE;
1349
1350 /*
1351 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1352 * so follow TRANSPORT_NEW_CMD processing thread context usage
1353 * and call transport_generic_request_failure() if necessary..
1354 */
1355 ret = transport_generic_new_cmd(cmd);
1356 if (ret)
1357 transport_generic_request_failure(cmd, ret);
1358 return 0;
1359 }
1360 EXPORT_SYMBOL(transport_handle_cdb_direct);
1361
1362 sense_reason_t
1363 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1364 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1365 {
1366 if (!sgl || !sgl_count)
1367 return 0;
1368
1369 /*
1370 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1371 * scatterlists already have been set to follow what the fabric
1372 * passes for the original expected data transfer length.
1373 */
1374 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1375 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1376 " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1377 return TCM_INVALID_CDB_FIELD;
1378 }
1379
1380 cmd->t_data_sg = sgl;
1381 cmd->t_data_nents = sgl_count;
1382 cmd->t_bidi_data_sg = sgl_bidi;
1383 cmd->t_bidi_data_nents = sgl_bidi_count;
1384
1385 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1386 return 0;
1387 }
1388
1389 /*
1390 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1391 * se_cmd + use pre-allocated SGL memory.
1392 *
1393 * @se_cmd: command descriptor to submit
1394 * @se_sess: associated se_sess for endpoint
1395 * @cdb: pointer to SCSI CDB
1396 * @sense: pointer to SCSI sense buffer
1397 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1398 * @data_length: fabric expected data transfer length
1399 * @task_addr: SAM task attribute
1400 * @data_dir: DMA data direction
1401 * @flags: flags for command submission from target_sc_flags_tables
1402 * @sgl: struct scatterlist memory for unidirectional mapping
1403 * @sgl_count: scatterlist count for unidirectional mapping
1404 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1405 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1406 * @sgl_prot: struct scatterlist memory protection information
1407 * @sgl_prot_count: scatterlist count for protection information
1408 *
1409 * Task tags are supported if the caller has set @se_cmd->tag.
1410 *
1411 * Returns non zero to signal active I/O shutdown failure. All other
1412 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1413 * but still return zero here.
1414 *
1415 * This may only be called from process context, and also currently
1416 * assumes internal allocation of fabric payload buffer by target-core.
1417 */
1418 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1419 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1420 u32 data_length, int task_attr, int data_dir, int flags,
1421 struct scatterlist *sgl, u32 sgl_count,
1422 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1423 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1424 {
1425 struct se_portal_group *se_tpg;
1426 sense_reason_t rc;
1427 int ret;
1428
1429 se_tpg = se_sess->se_tpg;
1430 BUG_ON(!se_tpg);
1431 BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1432 BUG_ON(in_interrupt());
1433 /*
1434 * Initialize se_cmd for target operation. From this point
1435 * exceptions are handled by sending exception status via
1436 * target_core_fabric_ops->queue_status() callback
1437 */
1438 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1439 data_length, data_dir, task_attr, sense);
1440 if (flags & TARGET_SCF_UNKNOWN_SIZE)
1441 se_cmd->unknown_data_length = 1;
1442 /*
1443 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1444 * se_sess->sess_cmd_list. A second kref_get here is necessary
1445 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1446 * kref_put() to happen during fabric packet acknowledgement.
1447 */
1448 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1449 if (ret)
1450 return ret;
1451 /*
1452 * Signal bidirectional data payloads to target-core
1453 */
1454 if (flags & TARGET_SCF_BIDI_OP)
1455 se_cmd->se_cmd_flags |= SCF_BIDI;
1456 /*
1457 * Locate se_lun pointer and attach it to struct se_cmd
1458 */
1459 rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1460 if (rc) {
1461 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1462 target_put_sess_cmd(se_cmd);
1463 return 0;
1464 }
1465
1466 rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1467 if (rc != 0) {
1468 transport_generic_request_failure(se_cmd, rc);
1469 return 0;
1470 }
1471
1472 /*
1473 * Save pointers for SGLs containing protection information,
1474 * if present.
1475 */
1476 if (sgl_prot_count) {
1477 se_cmd->t_prot_sg = sgl_prot;
1478 se_cmd->t_prot_nents = sgl_prot_count;
1479 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1480 }
1481
1482 /*
1483 * When a non zero sgl_count has been passed perform SGL passthrough
1484 * mapping for pre-allocated fabric memory instead of having target
1485 * core perform an internal SGL allocation..
1486 */
1487 if (sgl_count != 0) {
1488 BUG_ON(!sgl);
1489
1490 /*
1491 * A work-around for tcm_loop as some userspace code via
1492 * scsi-generic do not memset their associated read buffers,
1493 * so go ahead and do that here for type non-data CDBs. Also
1494 * note that this is currently guaranteed to be a single SGL
1495 * for this case by target core in target_setup_cmd_from_cdb()
1496 * -> transport_generic_cmd_sequencer().
1497 */
1498 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1499 se_cmd->data_direction == DMA_FROM_DEVICE) {
1500 unsigned char *buf = NULL;
1501
1502 if (sgl)
1503 buf = kmap(sg_page(sgl)) + sgl->offset;
1504
1505 if (buf) {
1506 memset(buf, 0, sgl->length);
1507 kunmap(sg_page(sgl));
1508 }
1509 }
1510
1511 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1512 sgl_bidi, sgl_bidi_count);
1513 if (rc != 0) {
1514 transport_generic_request_failure(se_cmd, rc);
1515 return 0;
1516 }
1517 }
1518
1519 /*
1520 * Check if we need to delay processing because of ALUA
1521 * Active/NonOptimized primary access state..
1522 */
1523 core_alua_check_nonop_delay(se_cmd);
1524
1525 transport_handle_cdb_direct(se_cmd);
1526 return 0;
1527 }
1528 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1529
1530 /*
1531 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1532 *
1533 * @se_cmd: command descriptor to submit
1534 * @se_sess: associated se_sess for endpoint
1535 * @cdb: pointer to SCSI CDB
1536 * @sense: pointer to SCSI sense buffer
1537 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1538 * @data_length: fabric expected data transfer length
1539 * @task_addr: SAM task attribute
1540 * @data_dir: DMA data direction
1541 * @flags: flags for command submission from target_sc_flags_tables
1542 *
1543 * Task tags are supported if the caller has set @se_cmd->tag.
1544 *
1545 * Returns non zero to signal active I/O shutdown failure. All other
1546 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1547 * but still return zero here.
1548 *
1549 * This may only be called from process context, and also currently
1550 * assumes internal allocation of fabric payload buffer by target-core.
1551 *
1552 * It also assumes interal target core SGL memory allocation.
1553 */
1554 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1555 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1556 u32 data_length, int task_attr, int data_dir, int flags)
1557 {
1558 return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1559 unpacked_lun, data_length, task_attr, data_dir,
1560 flags, NULL, 0, NULL, 0, NULL, 0);
1561 }
1562 EXPORT_SYMBOL(target_submit_cmd);
1563
1564 static void target_complete_tmr_failure(struct work_struct *work)
1565 {
1566 struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1567
1568 se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1569 se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1570
1571 transport_cmd_check_stop_to_fabric(se_cmd);
1572 }
1573
1574 /**
1575 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1576 * for TMR CDBs
1577 *
1578 * @se_cmd: command descriptor to submit
1579 * @se_sess: associated se_sess for endpoint
1580 * @sense: pointer to SCSI sense buffer
1581 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1582 * @fabric_context: fabric context for TMR req
1583 * @tm_type: Type of TM request
1584 * @gfp: gfp type for caller
1585 * @tag: referenced task tag for TMR_ABORT_TASK
1586 * @flags: submit cmd flags
1587 *
1588 * Callable from all contexts.
1589 **/
1590
1591 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1592 unsigned char *sense, u64 unpacked_lun,
1593 void *fabric_tmr_ptr, unsigned char tm_type,
1594 gfp_t gfp, u64 tag, int flags)
1595 {
1596 struct se_portal_group *se_tpg;
1597 int ret;
1598
1599 se_tpg = se_sess->se_tpg;
1600 BUG_ON(!se_tpg);
1601
1602 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1603 0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1604 /*
1605 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1606 * allocation failure.
1607 */
1608 ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1609 if (ret < 0)
1610 return -ENOMEM;
1611
1612 if (tm_type == TMR_ABORT_TASK)
1613 se_cmd->se_tmr_req->ref_task_tag = tag;
1614
1615 /* See target_submit_cmd for commentary */
1616 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1617 if (ret) {
1618 core_tmr_release_req(se_cmd->se_tmr_req);
1619 return ret;
1620 }
1621
1622 ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1623 if (ret) {
1624 /*
1625 * For callback during failure handling, push this work off
1626 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1627 */
1628 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1629 schedule_work(&se_cmd->work);
1630 return 0;
1631 }
1632 transport_generic_handle_tmr(se_cmd);
1633 return 0;
1634 }
1635 EXPORT_SYMBOL(target_submit_tmr);
1636
1637 /*
1638 * If the cmd is active, request it to be stopped and sleep until it
1639 * has completed.
1640 */
1641 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1642 __releases(&cmd->t_state_lock)
1643 __acquires(&cmd->t_state_lock)
1644 {
1645 bool was_active = false;
1646
1647 if (cmd->transport_state & CMD_T_BUSY) {
1648 cmd->transport_state |= CMD_T_REQUEST_STOP;
1649 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1650
1651 pr_debug("cmd %p waiting to complete\n", cmd);
1652 wait_for_completion(&cmd->task_stop_comp);
1653 pr_debug("cmd %p stopped successfully\n", cmd);
1654
1655 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1656 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1657 cmd->transport_state &= ~CMD_T_BUSY;
1658 was_active = true;
1659 }
1660
1661 return was_active;
1662 }
1663
1664 /*
1665 * Handle SAM-esque emulation for generic transport request failures.
1666 */
1667 void transport_generic_request_failure(struct se_cmd *cmd,
1668 sense_reason_t sense_reason)
1669 {
1670 int ret = 0, post_ret = 0;
1671
1672 pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08llx"
1673 " CDB: 0x%02x\n", cmd, cmd->tag, cmd->t_task_cdb[0]);
1674 pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1675 cmd->se_tfo->get_cmd_state(cmd),
1676 cmd->t_state, sense_reason);
1677 pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1678 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1679 (cmd->transport_state & CMD_T_STOP) != 0,
1680 (cmd->transport_state & CMD_T_SENT) != 0);
1681
1682 /*
1683 * For SAM Task Attribute emulation for failed struct se_cmd
1684 */
1685 transport_complete_task_attr(cmd);
1686 /*
1687 * Handle special case for COMPARE_AND_WRITE failure, where the
1688 * callback is expected to drop the per device ->caw_sem.
1689 */
1690 if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1691 cmd->transport_complete_callback)
1692 cmd->transport_complete_callback(cmd, false, &post_ret);
1693
1694 switch (sense_reason) {
1695 case TCM_NON_EXISTENT_LUN:
1696 case TCM_UNSUPPORTED_SCSI_OPCODE:
1697 case TCM_INVALID_CDB_FIELD:
1698 case TCM_INVALID_PARAMETER_LIST:
1699 case TCM_PARAMETER_LIST_LENGTH_ERROR:
1700 case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1701 case TCM_UNKNOWN_MODE_PAGE:
1702 case TCM_WRITE_PROTECTED:
1703 case TCM_ADDRESS_OUT_OF_RANGE:
1704 case TCM_CHECK_CONDITION_ABORT_CMD:
1705 case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1706 case TCM_CHECK_CONDITION_NOT_READY:
1707 case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1708 case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1709 case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1710 break;
1711 case TCM_OUT_OF_RESOURCES:
1712 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1713 break;
1714 case TCM_RESERVATION_CONFLICT:
1715 /*
1716 * No SENSE Data payload for this case, set SCSI Status
1717 * and queue the response to $FABRIC_MOD.
1718 *
1719 * Uses linux/include/scsi/scsi.h SAM status codes defs
1720 */
1721 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1722 /*
1723 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1724 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1725 * CONFLICT STATUS.
1726 *
1727 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1728 */
1729 if (cmd->se_sess &&
1730 cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1731 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1732 cmd->orig_fe_lun, 0x2C,
1733 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1734 }
1735 trace_target_cmd_complete(cmd);
1736 ret = cmd->se_tfo->queue_status(cmd);
1737 if (ret == -EAGAIN || ret == -ENOMEM)
1738 goto queue_full;
1739 goto check_stop;
1740 default:
1741 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1742 cmd->t_task_cdb[0], sense_reason);
1743 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1744 break;
1745 }
1746
1747 ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1748 if (ret == -EAGAIN || ret == -ENOMEM)
1749 goto queue_full;
1750
1751 check_stop:
1752 transport_lun_remove_cmd(cmd);
1753 transport_cmd_check_stop_to_fabric(cmd);
1754 return;
1755
1756 queue_full:
1757 cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1758 transport_handle_queue_full(cmd, cmd->se_dev);
1759 }
1760 EXPORT_SYMBOL(transport_generic_request_failure);
1761
1762 void __target_execute_cmd(struct se_cmd *cmd)
1763 {
1764 sense_reason_t ret;
1765
1766 if (cmd->execute_cmd) {
1767 ret = cmd->execute_cmd(cmd);
1768 if (ret) {
1769 spin_lock_irq(&cmd->t_state_lock);
1770 cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1771 spin_unlock_irq(&cmd->t_state_lock);
1772
1773 transport_generic_request_failure(cmd, ret);
1774 }
1775 }
1776 }
1777
1778 static int target_write_prot_action(struct se_cmd *cmd)
1779 {
1780 u32 sectors;
1781 /*
1782 * Perform WRITE_INSERT of PI using software emulation when backend
1783 * device has PI enabled, if the transport has not already generated
1784 * PI using hardware WRITE_INSERT offload.
1785 */
1786 switch (cmd->prot_op) {
1787 case TARGET_PROT_DOUT_INSERT:
1788 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1789 sbc_dif_generate(cmd);
1790 break;
1791 case TARGET_PROT_DOUT_STRIP:
1792 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1793 break;
1794
1795 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1796 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1797 sectors, 0, cmd->t_prot_sg, 0);
1798 if (unlikely(cmd->pi_err)) {
1799 spin_lock_irq(&cmd->t_state_lock);
1800 cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1801 spin_unlock_irq(&cmd->t_state_lock);
1802 transport_generic_request_failure(cmd, cmd->pi_err);
1803 return -1;
1804 }
1805 break;
1806 default:
1807 break;
1808 }
1809
1810 return 0;
1811 }
1812
1813 static bool target_handle_task_attr(struct se_cmd *cmd)
1814 {
1815 struct se_device *dev = cmd->se_dev;
1816
1817 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1818 return false;
1819
1820 /*
1821 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1822 * to allow the passed struct se_cmd list of tasks to the front of the list.
1823 */
1824 switch (cmd->sam_task_attr) {
1825 case TCM_HEAD_TAG:
1826 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1827 cmd->t_task_cdb[0]);
1828 return false;
1829 case TCM_ORDERED_TAG:
1830 atomic_inc_mb(&dev->dev_ordered_sync);
1831
1832 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1833 cmd->t_task_cdb[0]);
1834
1835 /*
1836 * Execute an ORDERED command if no other older commands
1837 * exist that need to be completed first.
1838 */
1839 if (!atomic_read(&dev->simple_cmds))
1840 return false;
1841 break;
1842 default:
1843 /*
1844 * For SIMPLE and UNTAGGED Task Attribute commands
1845 */
1846 atomic_inc_mb(&dev->simple_cmds);
1847 break;
1848 }
1849
1850 if (atomic_read(&dev->dev_ordered_sync) == 0)
1851 return false;
1852
1853 spin_lock(&dev->delayed_cmd_lock);
1854 list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1855 spin_unlock(&dev->delayed_cmd_lock);
1856
1857 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
1858 cmd->t_task_cdb[0], cmd->sam_task_attr);
1859 return true;
1860 }
1861
1862 void target_execute_cmd(struct se_cmd *cmd)
1863 {
1864 /*
1865 * If the received CDB has aleady been aborted stop processing it here.
1866 */
1867 if (transport_check_aborted_status(cmd, 1))
1868 return;
1869
1870 /*
1871 * Determine if frontend context caller is requesting the stopping of
1872 * this command for frontend exceptions.
1873 */
1874 spin_lock_irq(&cmd->t_state_lock);
1875 if (cmd->transport_state & CMD_T_STOP) {
1876 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1877 __func__, __LINE__, cmd->tag);
1878
1879 spin_unlock_irq(&cmd->t_state_lock);
1880 complete_all(&cmd->t_transport_stop_comp);
1881 return;
1882 }
1883
1884 cmd->t_state = TRANSPORT_PROCESSING;
1885 cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1886 spin_unlock_irq(&cmd->t_state_lock);
1887
1888 if (target_write_prot_action(cmd))
1889 return;
1890
1891 if (target_handle_task_attr(cmd)) {
1892 spin_lock_irq(&cmd->t_state_lock);
1893 cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1894 spin_unlock_irq(&cmd->t_state_lock);
1895 return;
1896 }
1897
1898 __target_execute_cmd(cmd);
1899 }
1900 EXPORT_SYMBOL(target_execute_cmd);
1901
1902 /*
1903 * Process all commands up to the last received ORDERED task attribute which
1904 * requires another blocking boundary
1905 */
1906 static void target_restart_delayed_cmds(struct se_device *dev)
1907 {
1908 for (;;) {
1909 struct se_cmd *cmd;
1910
1911 spin_lock(&dev->delayed_cmd_lock);
1912 if (list_empty(&dev->delayed_cmd_list)) {
1913 spin_unlock(&dev->delayed_cmd_lock);
1914 break;
1915 }
1916
1917 cmd = list_entry(dev->delayed_cmd_list.next,
1918 struct se_cmd, se_delayed_node);
1919 list_del(&cmd->se_delayed_node);
1920 spin_unlock(&dev->delayed_cmd_lock);
1921
1922 __target_execute_cmd(cmd);
1923
1924 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1925 break;
1926 }
1927 }
1928
1929 /*
1930 * Called from I/O completion to determine which dormant/delayed
1931 * and ordered cmds need to have their tasks added to the execution queue.
1932 */
1933 static void transport_complete_task_attr(struct se_cmd *cmd)
1934 {
1935 struct se_device *dev = cmd->se_dev;
1936
1937 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1938 return;
1939
1940 if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1941 atomic_dec_mb(&dev->simple_cmds);
1942 dev->dev_cur_ordered_id++;
1943 pr_debug("Incremented dev->dev_cur_ordered_id: %u for SIMPLE\n",
1944 dev->dev_cur_ordered_id);
1945 } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1946 dev->dev_cur_ordered_id++;
1947 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
1948 dev->dev_cur_ordered_id);
1949 } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1950 atomic_dec_mb(&dev->dev_ordered_sync);
1951
1952 dev->dev_cur_ordered_id++;
1953 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
1954 dev->dev_cur_ordered_id);
1955 }
1956
1957 target_restart_delayed_cmds(dev);
1958 }
1959
1960 static void transport_complete_qf(struct se_cmd *cmd)
1961 {
1962 int ret = 0;
1963
1964 transport_complete_task_attr(cmd);
1965
1966 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1967 trace_target_cmd_complete(cmd);
1968 ret = cmd->se_tfo->queue_status(cmd);
1969 goto out;
1970 }
1971
1972 switch (cmd->data_direction) {
1973 case DMA_FROM_DEVICE:
1974 trace_target_cmd_complete(cmd);
1975 ret = cmd->se_tfo->queue_data_in(cmd);
1976 break;
1977 case DMA_TO_DEVICE:
1978 if (cmd->se_cmd_flags & SCF_BIDI) {
1979 ret = cmd->se_tfo->queue_data_in(cmd);
1980 break;
1981 }
1982 /* Fall through for DMA_TO_DEVICE */
1983 case DMA_NONE:
1984 trace_target_cmd_complete(cmd);
1985 ret = cmd->se_tfo->queue_status(cmd);
1986 break;
1987 default:
1988 break;
1989 }
1990
1991 out:
1992 if (ret < 0) {
1993 transport_handle_queue_full(cmd, cmd->se_dev);
1994 return;
1995 }
1996 transport_lun_remove_cmd(cmd);
1997 transport_cmd_check_stop_to_fabric(cmd);
1998 }
1999
2000 static void transport_handle_queue_full(
2001 struct se_cmd *cmd,
2002 struct se_device *dev)
2003 {
2004 spin_lock_irq(&dev->qf_cmd_lock);
2005 list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2006 atomic_inc_mb(&dev->dev_qf_count);
2007 spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2008
2009 schedule_work(&cmd->se_dev->qf_work_queue);
2010 }
2011
2012 static bool target_read_prot_action(struct se_cmd *cmd)
2013 {
2014 switch (cmd->prot_op) {
2015 case TARGET_PROT_DIN_STRIP:
2016 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2017 u32 sectors = cmd->data_length >>
2018 ilog2(cmd->se_dev->dev_attrib.block_size);
2019
2020 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2021 sectors, 0, cmd->t_prot_sg,
2022 0);
2023 if (cmd->pi_err)
2024 return true;
2025 }
2026 break;
2027 case TARGET_PROT_DIN_INSERT:
2028 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2029 break;
2030
2031 sbc_dif_generate(cmd);
2032 break;
2033 default:
2034 break;
2035 }
2036
2037 return false;
2038 }
2039
2040 static void target_complete_ok_work(struct work_struct *work)
2041 {
2042 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2043 int ret;
2044
2045 /*
2046 * Check if we need to move delayed/dormant tasks from cmds on the
2047 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2048 * Attribute.
2049 */
2050 transport_complete_task_attr(cmd);
2051
2052 /*
2053 * Check to schedule QUEUE_FULL work, or execute an existing
2054 * cmd->transport_qf_callback()
2055 */
2056 if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2057 schedule_work(&cmd->se_dev->qf_work_queue);
2058
2059 /*
2060 * Check if we need to send a sense buffer from
2061 * the struct se_cmd in question.
2062 */
2063 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2064 WARN_ON(!cmd->scsi_status);
2065 ret = transport_send_check_condition_and_sense(
2066 cmd, 0, 1);
2067 if (ret == -EAGAIN || ret == -ENOMEM)
2068 goto queue_full;
2069
2070 transport_lun_remove_cmd(cmd);
2071 transport_cmd_check_stop_to_fabric(cmd);
2072 return;
2073 }
2074 /*
2075 * Check for a callback, used by amongst other things
2076 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2077 */
2078 if (cmd->transport_complete_callback) {
2079 sense_reason_t rc;
2080 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2081 bool zero_dl = !(cmd->data_length);
2082 int post_ret = 0;
2083
2084 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2085 if (!rc && !post_ret) {
2086 if (caw && zero_dl)
2087 goto queue_rsp;
2088
2089 return;
2090 } else if (rc) {
2091 ret = transport_send_check_condition_and_sense(cmd,
2092 rc, 0);
2093 if (ret == -EAGAIN || ret == -ENOMEM)
2094 goto queue_full;
2095
2096 transport_lun_remove_cmd(cmd);
2097 transport_cmd_check_stop_to_fabric(cmd);
2098 return;
2099 }
2100 }
2101
2102 queue_rsp:
2103 switch (cmd->data_direction) {
2104 case DMA_FROM_DEVICE:
2105 atomic_long_add(cmd->data_length,
2106 &cmd->se_lun->lun_stats.tx_data_octets);
2107 /*
2108 * Perform READ_STRIP of PI using software emulation when
2109 * backend had PI enabled, if the transport will not be
2110 * performing hardware READ_STRIP offload.
2111 */
2112 if (target_read_prot_action(cmd)) {
2113 ret = transport_send_check_condition_and_sense(cmd,
2114 cmd->pi_err, 0);
2115 if (ret == -EAGAIN || ret == -ENOMEM)
2116 goto queue_full;
2117
2118 transport_lun_remove_cmd(cmd);
2119 transport_cmd_check_stop_to_fabric(cmd);
2120 return;
2121 }
2122
2123 trace_target_cmd_complete(cmd);
2124 ret = cmd->se_tfo->queue_data_in(cmd);
2125 if (ret == -EAGAIN || ret == -ENOMEM)
2126 goto queue_full;
2127 break;
2128 case DMA_TO_DEVICE:
2129 atomic_long_add(cmd->data_length,
2130 &cmd->se_lun->lun_stats.rx_data_octets);
2131 /*
2132 * Check if we need to send READ payload for BIDI-COMMAND
2133 */
2134 if (cmd->se_cmd_flags & SCF_BIDI) {
2135 atomic_long_add(cmd->data_length,
2136 &cmd->se_lun->lun_stats.tx_data_octets);
2137 ret = cmd->se_tfo->queue_data_in(cmd);
2138 if (ret == -EAGAIN || ret == -ENOMEM)
2139 goto queue_full;
2140 break;
2141 }
2142 /* Fall through for DMA_TO_DEVICE */
2143 case DMA_NONE:
2144 trace_target_cmd_complete(cmd);
2145 ret = cmd->se_tfo->queue_status(cmd);
2146 if (ret == -EAGAIN || ret == -ENOMEM)
2147 goto queue_full;
2148 break;
2149 default:
2150 break;
2151 }
2152
2153 transport_lun_remove_cmd(cmd);
2154 transport_cmd_check_stop_to_fabric(cmd);
2155 return;
2156
2157 queue_full:
2158 pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2159 " data_direction: %d\n", cmd, cmd->data_direction);
2160 cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2161 transport_handle_queue_full(cmd, cmd->se_dev);
2162 }
2163
2164 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2165 {
2166 struct scatterlist *sg;
2167 int count;
2168
2169 for_each_sg(sgl, sg, nents, count)
2170 __free_page(sg_page(sg));
2171
2172 kfree(sgl);
2173 }
2174
2175 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2176 {
2177 /*
2178 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2179 * emulation, and free + reset pointers if necessary..
2180 */
2181 if (!cmd->t_data_sg_orig)
2182 return;
2183
2184 kfree(cmd->t_data_sg);
2185 cmd->t_data_sg = cmd->t_data_sg_orig;
2186 cmd->t_data_sg_orig = NULL;
2187 cmd->t_data_nents = cmd->t_data_nents_orig;
2188 cmd->t_data_nents_orig = 0;
2189 }
2190
2191 static inline void transport_free_pages(struct se_cmd *cmd)
2192 {
2193 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2194 transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2195 cmd->t_prot_sg = NULL;
2196 cmd->t_prot_nents = 0;
2197 }
2198
2199 if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2200 /*
2201 * Release special case READ buffer payload required for
2202 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2203 */
2204 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2205 transport_free_sgl(cmd->t_bidi_data_sg,
2206 cmd->t_bidi_data_nents);
2207 cmd->t_bidi_data_sg = NULL;
2208 cmd->t_bidi_data_nents = 0;
2209 }
2210 transport_reset_sgl_orig(cmd);
2211 return;
2212 }
2213 transport_reset_sgl_orig(cmd);
2214
2215 transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2216 cmd->t_data_sg = NULL;
2217 cmd->t_data_nents = 0;
2218
2219 transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2220 cmd->t_bidi_data_sg = NULL;
2221 cmd->t_bidi_data_nents = 0;
2222 }
2223
2224 /**
2225 * transport_release_cmd - free a command
2226 * @cmd: command to free
2227 *
2228 * This routine unconditionally frees a command, and reference counting
2229 * or list removal must be done in the caller.
2230 */
2231 static int transport_release_cmd(struct se_cmd *cmd)
2232 {
2233 BUG_ON(!cmd->se_tfo);
2234
2235 if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2236 core_tmr_release_req(cmd->se_tmr_req);
2237 if (cmd->t_task_cdb != cmd->__t_task_cdb)
2238 kfree(cmd->t_task_cdb);
2239 /*
2240 * If this cmd has been setup with target_get_sess_cmd(), drop
2241 * the kref and call ->release_cmd() in kref callback.
2242 */
2243 return target_put_sess_cmd(cmd);
2244 }
2245
2246 /**
2247 * transport_put_cmd - release a reference to a command
2248 * @cmd: command to release
2249 *
2250 * This routine releases our reference to the command and frees it if possible.
2251 */
2252 static int transport_put_cmd(struct se_cmd *cmd)
2253 {
2254 transport_free_pages(cmd);
2255 return transport_release_cmd(cmd);
2256 }
2257
2258 void *transport_kmap_data_sg(struct se_cmd *cmd)
2259 {
2260 struct scatterlist *sg = cmd->t_data_sg;
2261 struct page **pages;
2262 int i;
2263
2264 /*
2265 * We need to take into account a possible offset here for fabrics like
2266 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2267 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2268 */
2269 if (!cmd->t_data_nents)
2270 return NULL;
2271
2272 BUG_ON(!sg);
2273 if (cmd->t_data_nents == 1)
2274 return kmap(sg_page(sg)) + sg->offset;
2275
2276 /* >1 page. use vmap */
2277 pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2278 if (!pages)
2279 return NULL;
2280
2281 /* convert sg[] to pages[] */
2282 for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2283 pages[i] = sg_page(sg);
2284 }
2285
2286 cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
2287 kfree(pages);
2288 if (!cmd->t_data_vmap)
2289 return NULL;
2290
2291 return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2292 }
2293 EXPORT_SYMBOL(transport_kmap_data_sg);
2294
2295 void transport_kunmap_data_sg(struct se_cmd *cmd)
2296 {
2297 if (!cmd->t_data_nents) {
2298 return;
2299 } else if (cmd->t_data_nents == 1) {
2300 kunmap(sg_page(cmd->t_data_sg));
2301 return;
2302 }
2303
2304 vunmap(cmd->t_data_vmap);
2305 cmd->t_data_vmap = NULL;
2306 }
2307 EXPORT_SYMBOL(transport_kunmap_data_sg);
2308
2309 int
2310 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2311 bool zero_page)
2312 {
2313 struct scatterlist *sg;
2314 struct page *page;
2315 gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2316 unsigned int nent;
2317 int i = 0;
2318
2319 nent = DIV_ROUND_UP(length, PAGE_SIZE);
2320 sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2321 if (!sg)
2322 return -ENOMEM;
2323
2324 sg_init_table(sg, nent);
2325
2326 while (length) {
2327 u32 page_len = min_t(u32, length, PAGE_SIZE);
2328 page = alloc_page(GFP_KERNEL | zero_flag);
2329 if (!page)
2330 goto out;
2331
2332 sg_set_page(&sg[i], page, page_len, 0);
2333 length -= page_len;
2334 i++;
2335 }
2336 *sgl = sg;
2337 *nents = nent;
2338 return 0;
2339
2340 out:
2341 while (i > 0) {
2342 i--;
2343 __free_page(sg_page(&sg[i]));
2344 }
2345 kfree(sg);
2346 return -ENOMEM;
2347 }
2348
2349 /*
2350 * Allocate any required resources to execute the command. For writes we
2351 * might not have the payload yet, so notify the fabric via a call to
2352 * ->write_pending instead. Otherwise place it on the execution queue.
2353 */
2354 sense_reason_t
2355 transport_generic_new_cmd(struct se_cmd *cmd)
2356 {
2357 int ret = 0;
2358 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2359
2360 if (cmd->prot_op != TARGET_PROT_NORMAL &&
2361 !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2362 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2363 cmd->prot_length, true);
2364 if (ret < 0)
2365 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2366 }
2367
2368 /*
2369 * Determine is the TCM fabric module has already allocated physical
2370 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2371 * beforehand.
2372 */
2373 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2374 cmd->data_length) {
2375
2376 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2377 (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2378 u32 bidi_length;
2379
2380 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2381 bidi_length = cmd->t_task_nolb *
2382 cmd->se_dev->dev_attrib.block_size;
2383 else
2384 bidi_length = cmd->data_length;
2385
2386 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2387 &cmd->t_bidi_data_nents,
2388 bidi_length, zero_flag);
2389 if (ret < 0)
2390 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2391 }
2392
2393 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2394 cmd->data_length, zero_flag);
2395 if (ret < 0)
2396 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2397 } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2398 cmd->data_length) {
2399 /*
2400 * Special case for COMPARE_AND_WRITE with fabrics
2401 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2402 */
2403 u32 caw_length = cmd->t_task_nolb *
2404 cmd->se_dev->dev_attrib.block_size;
2405
2406 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2407 &cmd->t_bidi_data_nents,
2408 caw_length, zero_flag);
2409 if (ret < 0)
2410 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2411 }
2412 /*
2413 * If this command is not a write we can execute it right here,
2414 * for write buffers we need to notify the fabric driver first
2415 * and let it call back once the write buffers are ready.
2416 */
2417 target_add_to_state_list(cmd);
2418 if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2419 target_execute_cmd(cmd);
2420 return 0;
2421 }
2422 transport_cmd_check_stop(cmd, false, true);
2423
2424 ret = cmd->se_tfo->write_pending(cmd);
2425 if (ret == -EAGAIN || ret == -ENOMEM)
2426 goto queue_full;
2427
2428 /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2429 WARN_ON(ret);
2430
2431 return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2432
2433 queue_full:
2434 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2435 cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2436 transport_handle_queue_full(cmd, cmd->se_dev);
2437 return 0;
2438 }
2439 EXPORT_SYMBOL(transport_generic_new_cmd);
2440
2441 static void transport_write_pending_qf(struct se_cmd *cmd)
2442 {
2443 int ret;
2444
2445 ret = cmd->se_tfo->write_pending(cmd);
2446 if (ret == -EAGAIN || ret == -ENOMEM) {
2447 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2448 cmd);
2449 transport_handle_queue_full(cmd, cmd->se_dev);
2450 }
2451 }
2452
2453 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2454 {
2455 unsigned long flags;
2456 int ret = 0;
2457
2458 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2459 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2460 transport_wait_for_tasks(cmd);
2461
2462 ret = transport_release_cmd(cmd);
2463 } else {
2464 if (wait_for_tasks)
2465 transport_wait_for_tasks(cmd);
2466 /*
2467 * Handle WRITE failure case where transport_generic_new_cmd()
2468 * has already added se_cmd to state_list, but fabric has
2469 * failed command before I/O submission.
2470 */
2471 if (cmd->state_active) {
2472 spin_lock_irqsave(&cmd->t_state_lock, flags);
2473 target_remove_from_state_list(cmd);
2474 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2475 }
2476
2477 if (cmd->se_lun)
2478 transport_lun_remove_cmd(cmd);
2479
2480 ret = transport_put_cmd(cmd);
2481 }
2482 return ret;
2483 }
2484 EXPORT_SYMBOL(transport_generic_free_cmd);
2485
2486 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2487 * @se_cmd: command descriptor to add
2488 * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
2489 */
2490 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2491 {
2492 struct se_session *se_sess = se_cmd->se_sess;
2493 unsigned long flags;
2494 int ret = 0;
2495
2496 /*
2497 * Add a second kref if the fabric caller is expecting to handle
2498 * fabric acknowledgement that requires two target_put_sess_cmd()
2499 * invocations before se_cmd descriptor release.
2500 */
2501 if (ack_kref)
2502 kref_get(&se_cmd->cmd_kref);
2503
2504 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2505 if (se_sess->sess_tearing_down) {
2506 ret = -ESHUTDOWN;
2507 goto out;
2508 }
2509 list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2510 out:
2511 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2512
2513 if (ret && ack_kref)
2514 target_put_sess_cmd(se_cmd);
2515
2516 return ret;
2517 }
2518 EXPORT_SYMBOL(target_get_sess_cmd);
2519
2520 static void target_release_cmd_kref(struct kref *kref)
2521 {
2522 struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2523 struct se_session *se_sess = se_cmd->se_sess;
2524 unsigned long flags;
2525
2526 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2527 if (list_empty(&se_cmd->se_cmd_list)) {
2528 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2529 se_cmd->se_tfo->release_cmd(se_cmd);
2530 return;
2531 }
2532 if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2533 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2534 complete(&se_cmd->cmd_wait_comp);
2535 return;
2536 }
2537 list_del(&se_cmd->se_cmd_list);
2538 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2539
2540 se_cmd->se_tfo->release_cmd(se_cmd);
2541 }
2542
2543 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2544 * @se_cmd: command descriptor to drop
2545 */
2546 int target_put_sess_cmd(struct se_cmd *se_cmd)
2547 {
2548 struct se_session *se_sess = se_cmd->se_sess;
2549
2550 if (!se_sess) {
2551 se_cmd->se_tfo->release_cmd(se_cmd);
2552 return 1;
2553 }
2554 return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2555 }
2556 EXPORT_SYMBOL(target_put_sess_cmd);
2557
2558 /* target_sess_cmd_list_set_waiting - Flag all commands in
2559 * sess_cmd_list to complete cmd_wait_comp. Set
2560 * sess_tearing_down so no more commands are queued.
2561 * @se_sess: session to flag
2562 */
2563 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2564 {
2565 struct se_cmd *se_cmd;
2566 unsigned long flags;
2567
2568 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2569 if (se_sess->sess_tearing_down) {
2570 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2571 return;
2572 }
2573 se_sess->sess_tearing_down = 1;
2574 list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2575
2576 list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2577 se_cmd->cmd_wait_set = 1;
2578
2579 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2580 }
2581 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2582
2583 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2584 * @se_sess: session to wait for active I/O
2585 */
2586 void target_wait_for_sess_cmds(struct se_session *se_sess)
2587 {
2588 struct se_cmd *se_cmd, *tmp_cmd;
2589 unsigned long flags;
2590
2591 list_for_each_entry_safe(se_cmd, tmp_cmd,
2592 &se_sess->sess_wait_list, se_cmd_list) {
2593 list_del(&se_cmd->se_cmd_list);
2594
2595 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2596 " %d\n", se_cmd, se_cmd->t_state,
2597 se_cmd->se_tfo->get_cmd_state(se_cmd));
2598
2599 wait_for_completion(&se_cmd->cmd_wait_comp);
2600 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2601 " fabric state: %d\n", se_cmd, se_cmd->t_state,
2602 se_cmd->se_tfo->get_cmd_state(se_cmd));
2603
2604 se_cmd->se_tfo->release_cmd(se_cmd);
2605 }
2606
2607 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2608 WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2609 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2610
2611 }
2612 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2613
2614 void transport_clear_lun_ref(struct se_lun *lun)
2615 {
2616 percpu_ref_kill(&lun->lun_ref);
2617 wait_for_completion(&lun->lun_ref_comp);
2618 }
2619
2620 /**
2621 * transport_wait_for_tasks - wait for completion to occur
2622 * @cmd: command to wait
2623 *
2624 * Called from frontend fabric context to wait for storage engine
2625 * to pause and/or release frontend generated struct se_cmd.
2626 */
2627 bool transport_wait_for_tasks(struct se_cmd *cmd)
2628 {
2629 unsigned long flags;
2630
2631 spin_lock_irqsave(&cmd->t_state_lock, flags);
2632 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2633 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2634 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2635 return false;
2636 }
2637
2638 if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2639 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2640 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2641 return false;
2642 }
2643
2644 if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2645 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2646 return false;
2647 }
2648
2649 cmd->transport_state |= CMD_T_STOP;
2650
2651 pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08llx i_state: %d, t_state: %d, CMD_T_STOP\n",
2652 cmd, cmd->tag, cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2653
2654 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2655
2656 wait_for_completion(&cmd->t_transport_stop_comp);
2657
2658 spin_lock_irqsave(&cmd->t_state_lock, flags);
2659 cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2660
2661 pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->t_transport_stop_comp) for ITT: 0x%08llx\n",
2662 cmd->tag);
2663
2664 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2665
2666 return true;
2667 }
2668 EXPORT_SYMBOL(transport_wait_for_tasks);
2669
2670 struct sense_info {
2671 u8 key;
2672 u8 asc;
2673 u8 ascq;
2674 bool add_sector_info;
2675 };
2676
2677 static const struct sense_info sense_info_table[] = {
2678 [TCM_NO_SENSE] = {
2679 .key = NOT_READY
2680 },
2681 [TCM_NON_EXISTENT_LUN] = {
2682 .key = ILLEGAL_REQUEST,
2683 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
2684 },
2685 [TCM_UNSUPPORTED_SCSI_OPCODE] = {
2686 .key = ILLEGAL_REQUEST,
2687 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2688 },
2689 [TCM_SECTOR_COUNT_TOO_MANY] = {
2690 .key = ILLEGAL_REQUEST,
2691 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2692 },
2693 [TCM_UNKNOWN_MODE_PAGE] = {
2694 .key = ILLEGAL_REQUEST,
2695 .asc = 0x24, /* INVALID FIELD IN CDB */
2696 },
2697 [TCM_CHECK_CONDITION_ABORT_CMD] = {
2698 .key = ABORTED_COMMAND,
2699 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
2700 .ascq = 0x03,
2701 },
2702 [TCM_INCORRECT_AMOUNT_OF_DATA] = {
2703 .key = ABORTED_COMMAND,
2704 .asc = 0x0c, /* WRITE ERROR */
2705 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
2706 },
2707 [TCM_INVALID_CDB_FIELD] = {
2708 .key = ILLEGAL_REQUEST,
2709 .asc = 0x24, /* INVALID FIELD IN CDB */
2710 },
2711 [TCM_INVALID_PARAMETER_LIST] = {
2712 .key = ILLEGAL_REQUEST,
2713 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
2714 },
2715 [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
2716 .key = ILLEGAL_REQUEST,
2717 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
2718 },
2719 [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
2720 .key = ILLEGAL_REQUEST,
2721 .asc = 0x0c, /* WRITE ERROR */
2722 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
2723 },
2724 [TCM_SERVICE_CRC_ERROR] = {
2725 .key = ABORTED_COMMAND,
2726 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
2727 .ascq = 0x05, /* N/A */
2728 },
2729 [TCM_SNACK_REJECTED] = {
2730 .key = ABORTED_COMMAND,
2731 .asc = 0x11, /* READ ERROR */
2732 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
2733 },
2734 [TCM_WRITE_PROTECTED] = {
2735 .key = DATA_PROTECT,
2736 .asc = 0x27, /* WRITE PROTECTED */
2737 },
2738 [TCM_ADDRESS_OUT_OF_RANGE] = {
2739 .key = ILLEGAL_REQUEST,
2740 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2741 },
2742 [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
2743 .key = UNIT_ATTENTION,
2744 },
2745 [TCM_CHECK_CONDITION_NOT_READY] = {
2746 .key = NOT_READY,
2747 },
2748 [TCM_MISCOMPARE_VERIFY] = {
2749 .key = MISCOMPARE,
2750 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
2751 .ascq = 0x00,
2752 },
2753 [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
2754 .key = ABORTED_COMMAND,
2755 .asc = 0x10,
2756 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
2757 .add_sector_info = true,
2758 },
2759 [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
2760 .key = ABORTED_COMMAND,
2761 .asc = 0x10,
2762 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2763 .add_sector_info = true,
2764 },
2765 [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
2766 .key = ABORTED_COMMAND,
2767 .asc = 0x10,
2768 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2769 .add_sector_info = true,
2770 },
2771 [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
2772 /*
2773 * Returning ILLEGAL REQUEST would cause immediate IO errors on
2774 * Solaris initiators. Returning NOT READY instead means the
2775 * operations will be retried a finite number of times and we
2776 * can survive intermittent errors.
2777 */
2778 .key = NOT_READY,
2779 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
2780 },
2781 };
2782
2783 static int translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
2784 {
2785 const struct sense_info *si;
2786 u8 *buffer = cmd->sense_buffer;
2787 int r = (__force int)reason;
2788 u8 asc, ascq;
2789 bool desc_format = target_sense_desc_format(cmd->se_dev);
2790
2791 if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
2792 si = &sense_info_table[r];
2793 else
2794 si = &sense_info_table[(__force int)
2795 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
2796
2797 if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
2798 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2799 WARN_ON_ONCE(asc == 0);
2800 } else if (si->asc == 0) {
2801 WARN_ON_ONCE(cmd->scsi_asc == 0);
2802 asc = cmd->scsi_asc;
2803 ascq = cmd->scsi_ascq;
2804 } else {
2805 asc = si->asc;
2806 ascq = si->ascq;
2807 }
2808
2809 scsi_build_sense_buffer(desc_format, buffer, si->key, asc, ascq);
2810 if (si->add_sector_info)
2811 return scsi_set_sense_information(buffer,
2812 cmd->scsi_sense_length,
2813 cmd->bad_sector);
2814
2815 return 0;
2816 }
2817
2818 int
2819 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2820 sense_reason_t reason, int from_transport)
2821 {
2822 unsigned long flags;
2823
2824 spin_lock_irqsave(&cmd->t_state_lock, flags);
2825 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2826 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2827 return 0;
2828 }
2829 cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2830 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2831
2832 if (!from_transport) {
2833 int rc;
2834
2835 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2836 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2837 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
2838 rc = translate_sense_reason(cmd, reason);
2839 if (rc)
2840 return rc;
2841 }
2842
2843 trace_target_cmd_complete(cmd);
2844 return cmd->se_tfo->queue_status(cmd);
2845 }
2846 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2847
2848 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2849 {
2850 if (!(cmd->transport_state & CMD_T_ABORTED))
2851 return 0;
2852
2853 /*
2854 * If cmd has been aborted but either no status is to be sent or it has
2855 * already been sent, just return
2856 */
2857 if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
2858 return 1;
2859
2860 pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08llx\n",
2861 cmd->t_task_cdb[0], cmd->tag);
2862
2863 cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2864 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2865 trace_target_cmd_complete(cmd);
2866 cmd->se_tfo->queue_status(cmd);
2867
2868 return 1;
2869 }
2870 EXPORT_SYMBOL(transport_check_aborted_status);
2871
2872 void transport_send_task_abort(struct se_cmd *cmd)
2873 {
2874 unsigned long flags;
2875
2876 spin_lock_irqsave(&cmd->t_state_lock, flags);
2877 if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2878 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2879 return;
2880 }
2881 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2882
2883 /*
2884 * If there are still expected incoming fabric WRITEs, we wait
2885 * until until they have completed before sending a TASK_ABORTED
2886 * response. This response with TASK_ABORTED status will be
2887 * queued back to fabric module by transport_check_aborted_status().
2888 */
2889 if (cmd->data_direction == DMA_TO_DEVICE) {
2890 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2891 cmd->transport_state |= CMD_T_ABORTED;
2892 cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2893 return;
2894 }
2895 }
2896 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2897
2898 transport_lun_remove_cmd(cmd);
2899
2900 pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
2901 cmd->t_task_cdb[0], cmd->tag);
2902
2903 trace_target_cmd_complete(cmd);
2904 cmd->se_tfo->queue_status(cmd);
2905 }
2906
2907 static void target_tmr_work(struct work_struct *work)
2908 {
2909 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2910 struct se_device *dev = cmd->se_dev;
2911 struct se_tmr_req *tmr = cmd->se_tmr_req;
2912 int ret;
2913
2914 switch (tmr->function) {
2915 case TMR_ABORT_TASK:
2916 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2917 break;
2918 case TMR_ABORT_TASK_SET:
2919 case TMR_CLEAR_ACA:
2920 case TMR_CLEAR_TASK_SET:
2921 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2922 break;
2923 case TMR_LUN_RESET:
2924 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2925 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2926 TMR_FUNCTION_REJECTED;
2927 if (tmr->response == TMR_FUNCTION_COMPLETE) {
2928 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
2929 cmd->orig_fe_lun, 0x29,
2930 ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
2931 }
2932 break;
2933 case TMR_TARGET_WARM_RESET:
2934 tmr->response = TMR_FUNCTION_REJECTED;
2935 break;
2936 case TMR_TARGET_COLD_RESET:
2937 tmr->response = TMR_FUNCTION_REJECTED;
2938 break;
2939 default:
2940 pr_err("Uknown TMR function: 0x%02x.\n",
2941 tmr->function);
2942 tmr->response = TMR_FUNCTION_REJECTED;
2943 break;
2944 }
2945
2946 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2947 cmd->se_tfo->queue_tm_rsp(cmd);
2948
2949 transport_cmd_check_stop_to_fabric(cmd);
2950 }
2951
2952 int transport_generic_handle_tmr(
2953 struct se_cmd *cmd)
2954 {
2955 unsigned long flags;
2956
2957 spin_lock_irqsave(&cmd->t_state_lock, flags);
2958 cmd->transport_state |= CMD_T_ACTIVE;
2959 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2960
2961 INIT_WORK(&cmd->work, target_tmr_work);
2962 queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2963 return 0;
2964 }
2965 EXPORT_SYMBOL(transport_generic_handle_tmr);
2966
2967 bool
2968 target_check_wce(struct se_device *dev)
2969 {
2970 bool wce = false;
2971
2972 if (dev->transport->get_write_cache)
2973 wce = dev->transport->get_write_cache(dev);
2974 else if (dev->dev_attrib.emulate_write_cache > 0)
2975 wce = true;
2976
2977 return wce;
2978 }
2979
2980 bool
2981 target_check_fua(struct se_device *dev)
2982 {
2983 return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
2984 }
Linux kernel - Deliverables
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