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perf tools: Don't clone maps from parent when synthesizing forks
[linux/fpc-iii.git] / drivers / target / target_core_transport.c
blob4cf33e2cc7058843fd547ffc2da8a02a262dd5e8
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 translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason);
68 static void transport_handle_queue_full(struct se_cmd *cmd,
69 struct se_device *dev, int err, bool write_pending);
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 /**
228 * transport_init_session - initialize a session object
229 * @se_sess: Session object pointer.
230 *
231 * The caller must have zero-initialized @se_sess before calling this function.
232 */
233 void transport_init_session(struct se_session *se_sess)
234 {
235 INIT_LIST_HEAD(&se_sess->sess_list);
236 INIT_LIST_HEAD(&se_sess->sess_acl_list);
237 INIT_LIST_HEAD(&se_sess->sess_cmd_list);
238 spin_lock_init(&se_sess->sess_cmd_lock);
239 init_waitqueue_head(&se_sess->cmd_list_wq);
240 }
241 EXPORT_SYMBOL(transport_init_session);
242
243 /**
244 * transport_alloc_session - allocate a session object and initialize it
245 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
246 */
247 struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
248 {
249 struct se_session *se_sess;
250
251 se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
252 if (!se_sess) {
253 pr_err("Unable to allocate struct se_session from"
254 " se_sess_cache\n");
255 return ERR_PTR(-ENOMEM);
256 }
257 transport_init_session(se_sess);
258 se_sess->sup_prot_ops = sup_prot_ops;
259
260 return se_sess;
261 }
262 EXPORT_SYMBOL(transport_alloc_session);
263
264 /**
265 * transport_alloc_session_tags - allocate target driver private data
266 * @se_sess: Session pointer.
267 * @tag_num: Maximum number of in-flight commands between initiator and target.
268 * @tag_size: Size in bytes of the private data a target driver associates with
269 * each command.
270 */
271 int transport_alloc_session_tags(struct se_session *se_sess,
272 unsigned int tag_num, unsigned int tag_size)
273 {
274 int rc;
275
276 se_sess->sess_cmd_map = kcalloc(tag_size, tag_num,
277 GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
278 if (!se_sess->sess_cmd_map) {
279 se_sess->sess_cmd_map = vzalloc(array_size(tag_size, tag_num));
280 if (!se_sess->sess_cmd_map) {
281 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
282 return -ENOMEM;
283 }
284 }
285
286 rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
287 false, GFP_KERNEL, NUMA_NO_NODE);
288 if (rc < 0) {
289 pr_err("Unable to init se_sess->sess_tag_pool,"
290 " tag_num: %u\n", tag_num);
291 kvfree(se_sess->sess_cmd_map);
292 se_sess->sess_cmd_map = NULL;
293 return -ENOMEM;
294 }
295
296 return 0;
297 }
298 EXPORT_SYMBOL(transport_alloc_session_tags);
299
300 /**
301 * transport_init_session_tags - allocate a session and target driver private data
302 * @tag_num: Maximum number of in-flight commands between initiator and target.
303 * @tag_size: Size in bytes of the private data a target driver associates with
304 * each command.
305 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
306 */
307 static struct se_session *
308 transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
309 enum target_prot_op sup_prot_ops)
310 {
311 struct se_session *se_sess;
312 int rc;
313
314 if (tag_num != 0 && !tag_size) {
315 pr_err("init_session_tags called with percpu-ida tag_num:"
316 " %u, but zero tag_size\n", tag_num);
317 return ERR_PTR(-EINVAL);
318 }
319 if (!tag_num && tag_size) {
320 pr_err("init_session_tags called with percpu-ida tag_size:"
321 " %u, but zero tag_num\n", tag_size);
322 return ERR_PTR(-EINVAL);
323 }
324
325 se_sess = transport_alloc_session(sup_prot_ops);
326 if (IS_ERR(se_sess))
327 return se_sess;
328
329 rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
330 if (rc < 0) {
331 transport_free_session(se_sess);
332 return ERR_PTR(-ENOMEM);
333 }
334
335 return se_sess;
336 }
337
338 /*
339 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
340 */
341 void __transport_register_session(
342 struct se_portal_group *se_tpg,
343 struct se_node_acl *se_nacl,
344 struct se_session *se_sess,
345 void *fabric_sess_ptr)
346 {
347 const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
348 unsigned char buf[PR_REG_ISID_LEN];
349 unsigned long flags;
350
351 se_sess->se_tpg = se_tpg;
352 se_sess->fabric_sess_ptr = fabric_sess_ptr;
353 /*
354 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
355 *
356 * Only set for struct se_session's that will actually be moving I/O.
357 * eg: *NOT* discovery sessions.
358 */
359 if (se_nacl) {
360 /*
361 *
362 * Determine if fabric allows for T10-PI feature bits exposed to
363 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
364 *
365 * If so, then always save prot_type on a per se_node_acl node
366 * basis and re-instate the previous sess_prot_type to avoid
367 * disabling PI from below any previously initiator side
368 * registered LUNs.
369 */
370 if (se_nacl->saved_prot_type)
371 se_sess->sess_prot_type = se_nacl->saved_prot_type;
372 else if (tfo->tpg_check_prot_fabric_only)
373 se_sess->sess_prot_type = se_nacl->saved_prot_type =
374 tfo->tpg_check_prot_fabric_only(se_tpg);
375 /*
376 * If the fabric module supports an ISID based TransportID,
377 * save this value in binary from the fabric I_T Nexus now.
378 */
379 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
380 memset(&buf[0], 0, PR_REG_ISID_LEN);
381 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
382 &buf[0], PR_REG_ISID_LEN);
383 se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
384 }
385
386 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
387 /*
388 * The se_nacl->nacl_sess pointer will be set to the
389 * last active I_T Nexus for each struct se_node_acl.
390 */
391 se_nacl->nacl_sess = se_sess;
392
393 list_add_tail(&se_sess->sess_acl_list,
394 &se_nacl->acl_sess_list);
395 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
396 }
397 list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
398
399 pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
400 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
401 }
402 EXPORT_SYMBOL(__transport_register_session);
403
404 void transport_register_session(
405 struct se_portal_group *se_tpg,
406 struct se_node_acl *se_nacl,
407 struct se_session *se_sess,
408 void *fabric_sess_ptr)
409 {
410 unsigned long flags;
411
412 spin_lock_irqsave(&se_tpg->session_lock, flags);
413 __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
414 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
415 }
416 EXPORT_SYMBOL(transport_register_session);
417
418 struct se_session *
419 target_setup_session(struct se_portal_group *tpg,
420 unsigned int tag_num, unsigned int tag_size,
421 enum target_prot_op prot_op,
422 const char *initiatorname, void *private,
423 int (*callback)(struct se_portal_group *,
424 struct se_session *, void *))
425 {
426 struct se_session *sess;
427
428 /*
429 * If the fabric driver is using percpu-ida based pre allocation
430 * of I/O descriptor tags, go ahead and perform that setup now..
431 */
432 if (tag_num != 0)
433 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
434 else
435 sess = transport_alloc_session(prot_op);
436
437 if (IS_ERR(sess))
438 return sess;
439
440 sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
441 (unsigned char *)initiatorname);
442 if (!sess->se_node_acl) {
443 transport_free_session(sess);
444 return ERR_PTR(-EACCES);
445 }
446 /*
447 * Go ahead and perform any remaining fabric setup that is
448 * required before transport_register_session().
449 */
450 if (callback != NULL) {
451 int rc = callback(tpg, sess, private);
452 if (rc) {
453 transport_free_session(sess);
454 return ERR_PTR(rc);
455 }
456 }
457
458 transport_register_session(tpg, sess->se_node_acl, sess, private);
459 return sess;
460 }
461 EXPORT_SYMBOL(target_setup_session);
462
463 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
464 {
465 struct se_session *se_sess;
466 ssize_t len = 0;
467
468 spin_lock_bh(&se_tpg->session_lock);
469 list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
470 if (!se_sess->se_node_acl)
471 continue;
472 if (!se_sess->se_node_acl->dynamic_node_acl)
473 continue;
474 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
475 break;
476
477 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
478 se_sess->se_node_acl->initiatorname);
479 len += 1; /* Include NULL terminator */
480 }
481 spin_unlock_bh(&se_tpg->session_lock);
482
483 return len;
484 }
485 EXPORT_SYMBOL(target_show_dynamic_sessions);
486
487 static void target_complete_nacl(struct kref *kref)
488 {
489 struct se_node_acl *nacl = container_of(kref,
490 struct se_node_acl, acl_kref);
491 struct se_portal_group *se_tpg = nacl->se_tpg;
492
493 if (!nacl->dynamic_stop) {
494 complete(&nacl->acl_free_comp);
495 return;
496 }
497
498 mutex_lock(&se_tpg->acl_node_mutex);
499 list_del_init(&nacl->acl_list);
500 mutex_unlock(&se_tpg->acl_node_mutex);
501
502 core_tpg_wait_for_nacl_pr_ref(nacl);
503 core_free_device_list_for_node(nacl, se_tpg);
504 kfree(nacl);
505 }
506
507 void target_put_nacl(struct se_node_acl *nacl)
508 {
509 kref_put(&nacl->acl_kref, target_complete_nacl);
510 }
511 EXPORT_SYMBOL(target_put_nacl);
512
513 void transport_deregister_session_configfs(struct se_session *se_sess)
514 {
515 struct se_node_acl *se_nacl;
516 unsigned long flags;
517 /*
518 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
519 */
520 se_nacl = se_sess->se_node_acl;
521 if (se_nacl) {
522 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
523 if (!list_empty(&se_sess->sess_acl_list))
524 list_del_init(&se_sess->sess_acl_list);
525 /*
526 * If the session list is empty, then clear the pointer.
527 * Otherwise, set the struct se_session pointer from the tail
528 * element of the per struct se_node_acl active session list.
529 */
530 if (list_empty(&se_nacl->acl_sess_list))
531 se_nacl->nacl_sess = NULL;
532 else {
533 se_nacl->nacl_sess = container_of(
534 se_nacl->acl_sess_list.prev,
535 struct se_session, sess_acl_list);
536 }
537 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
538 }
539 }
540 EXPORT_SYMBOL(transport_deregister_session_configfs);
541
542 void transport_free_session(struct se_session *se_sess)
543 {
544 struct se_node_acl *se_nacl = se_sess->se_node_acl;
545
546 /*
547 * Drop the se_node_acl->nacl_kref obtained from within
548 * core_tpg_get_initiator_node_acl().
549 */
550 if (se_nacl) {
551 struct se_portal_group *se_tpg = se_nacl->se_tpg;
552 const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
553 unsigned long flags;
554
555 se_sess->se_node_acl = NULL;
556
557 /*
558 * Also determine if we need to drop the extra ->cmd_kref if
559 * it had been previously dynamically generated, and
560 * the endpoint is not caching dynamic ACLs.
561 */
562 mutex_lock(&se_tpg->acl_node_mutex);
563 if (se_nacl->dynamic_node_acl &&
564 !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
565 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
566 if (list_empty(&se_nacl->acl_sess_list))
567 se_nacl->dynamic_stop = true;
568 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
569
570 if (se_nacl->dynamic_stop)
571 list_del_init(&se_nacl->acl_list);
572 }
573 mutex_unlock(&se_tpg->acl_node_mutex);
574
575 if (se_nacl->dynamic_stop)
576 target_put_nacl(se_nacl);
577
578 target_put_nacl(se_nacl);
579 }
580 if (se_sess->sess_cmd_map) {
581 sbitmap_queue_free(&se_sess->sess_tag_pool);
582 kvfree(se_sess->sess_cmd_map);
583 }
584 kmem_cache_free(se_sess_cache, se_sess);
585 }
586 EXPORT_SYMBOL(transport_free_session);
587
588 void transport_deregister_session(struct se_session *se_sess)
589 {
590 struct se_portal_group *se_tpg = se_sess->se_tpg;
591 unsigned long flags;
592
593 if (!se_tpg) {
594 transport_free_session(se_sess);
595 return;
596 }
597
598 spin_lock_irqsave(&se_tpg->session_lock, flags);
599 list_del(&se_sess->sess_list);
600 se_sess->se_tpg = NULL;
601 se_sess->fabric_sess_ptr = NULL;
602 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
603
604 pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
605 se_tpg->se_tpg_tfo->get_fabric_name());
606 /*
607 * If last kref is dropping now for an explicit NodeACL, awake sleeping
608 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
609 * removal context from within transport_free_session() code.
610 *
611 * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
612 * to release all remaining generate_node_acl=1 created ACL resources.
613 */
614
615 transport_free_session(se_sess);
616 }
617 EXPORT_SYMBOL(transport_deregister_session);
618
619 void target_remove_session(struct se_session *se_sess)
620 {
621 transport_deregister_session_configfs(se_sess);
622 transport_deregister_session(se_sess);
623 }
624 EXPORT_SYMBOL(target_remove_session);
625
626 static void target_remove_from_state_list(struct se_cmd *cmd)
627 {
628 struct se_device *dev = cmd->se_dev;
629 unsigned long flags;
630
631 if (!dev)
632 return;
633
634 spin_lock_irqsave(&dev->execute_task_lock, flags);
635 if (cmd->state_active) {
636 list_del(&cmd->state_list);
637 cmd->state_active = false;
638 }
639 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
640 }
641
642 /*
643 * This function is called by the target core after the target core has
644 * finished processing a SCSI command or SCSI TMF. Both the regular command
645 * processing code and the code for aborting commands can call this
646 * function. CMD_T_STOP is set if and only if another thread is waiting
647 * inside transport_wait_for_tasks() for t_transport_stop_comp.
648 */
649 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
650 {
651 unsigned long flags;
652
653 target_remove_from_state_list(cmd);
654
655 /*
656 * Clear struct se_cmd->se_lun before the handoff to FE.
657 */
658 cmd->se_lun = NULL;
659
660 spin_lock_irqsave(&cmd->t_state_lock, flags);
661 /*
662 * Determine if frontend context caller is requesting the stopping of
663 * this command for frontend exceptions.
664 */
665 if (cmd->transport_state & CMD_T_STOP) {
666 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
667 __func__, __LINE__, cmd->tag);
668
669 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
670
671 complete_all(&cmd->t_transport_stop_comp);
672 return 1;
673 }
674 cmd->transport_state &= ~CMD_T_ACTIVE;
675 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
676
677 /*
678 * Some fabric modules like tcm_loop can release their internally
679 * allocated I/O reference and struct se_cmd now.
680 *
681 * Fabric modules are expected to return '1' here if the se_cmd being
682 * passed is released at this point, or zero if not being released.
683 */
684 return cmd->se_tfo->check_stop_free(cmd);
685 }
686
687 static void transport_lun_remove_cmd(struct se_cmd *cmd)
688 {
689 struct se_lun *lun = cmd->se_lun;
690
691 if (!lun)
692 return;
693
694 if (cmpxchg(&cmd->lun_ref_active, true, false))
695 percpu_ref_put(&lun->lun_ref);
696 }
697
698 int transport_cmd_finish_abort(struct se_cmd *cmd)
699 {
700 bool send_tas = cmd->transport_state & CMD_T_TAS;
701 bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF);
702 int ret = 0;
703
704 if (send_tas)
705 transport_send_task_abort(cmd);
706
707 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
708 transport_lun_remove_cmd(cmd);
709 /*
710 * Allow the fabric driver to unmap any resources before
711 * releasing the descriptor via TFO->release_cmd()
712 */
713 if (!send_tas)
714 cmd->se_tfo->aborted_task(cmd);
715
716 if (transport_cmd_check_stop_to_fabric(cmd))
717 return 1;
718 if (!send_tas && ack_kref)
719 ret = target_put_sess_cmd(cmd);
720
721 return ret;
722 }
723
724 static void target_complete_failure_work(struct work_struct *work)
725 {
726 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
727
728 transport_generic_request_failure(cmd,
729 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
730 }
731
732 /*
733 * Used when asking transport to copy Sense Data from the underlying
734 * Linux/SCSI struct scsi_cmnd
735 */
736 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
737 {
738 struct se_device *dev = cmd->se_dev;
739
740 WARN_ON(!cmd->se_lun);
741
742 if (!dev)
743 return NULL;
744
745 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
746 return NULL;
747
748 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
749
750 pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
751 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
752 return cmd->sense_buffer;
753 }
754
755 void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
756 {
757 unsigned char *cmd_sense_buf;
758 unsigned long flags;
759
760 spin_lock_irqsave(&cmd->t_state_lock, flags);
761 cmd_sense_buf = transport_get_sense_buffer(cmd);
762 if (!cmd_sense_buf) {
763 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
764 return;
765 }
766
767 cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
768 memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
769 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
770 }
771 EXPORT_SYMBOL(transport_copy_sense_to_cmd);
772
773 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
774 {
775 struct se_device *dev = cmd->se_dev;
776 int success;
777 unsigned long flags;
778
779 cmd->scsi_status = scsi_status;
780
781 spin_lock_irqsave(&cmd->t_state_lock, flags);
782 switch (cmd->scsi_status) {
783 case SAM_STAT_CHECK_CONDITION:
784 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
785 success = 1;
786 else
787 success = 0;
788 break;
789 default:
790 success = 1;
791 break;
792 }
793
794 /*
795 * Check for case where an explicit ABORT_TASK has been received
796 * and transport_wait_for_tasks() will be waiting for completion..
797 */
798 if (cmd->transport_state & CMD_T_ABORTED ||
799 cmd->transport_state & CMD_T_STOP) {
800 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
801 /*
802 * If COMPARE_AND_WRITE was stopped by __transport_wait_for_tasks(),
803 * release se_device->caw_sem obtained by sbc_compare_and_write()
804 * since target_complete_ok_work() or target_complete_failure_work()
805 * won't be called to invoke the normal CAW completion callbacks.
806 */
807 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
808 up(&dev->caw_sem);
809 }
810 complete_all(&cmd->t_transport_stop_comp);
811 return;
812 } else if (!success) {
813 INIT_WORK(&cmd->work, target_complete_failure_work);
814 } else {
815 INIT_WORK(&cmd->work, target_complete_ok_work);
816 }
817
818 cmd->t_state = TRANSPORT_COMPLETE;
819 cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
820 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
821
822 if (cmd->se_cmd_flags & SCF_USE_CPUID)
823 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
824 else
825 queue_work(target_completion_wq, &cmd->work);
826 }
827 EXPORT_SYMBOL(target_complete_cmd);
828
829 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
830 {
831 if ((scsi_status == SAM_STAT_GOOD ||
832 cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
833 length < cmd->data_length) {
834 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
835 cmd->residual_count += cmd->data_length - length;
836 } else {
837 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
838 cmd->residual_count = cmd->data_length - length;
839 }
840
841 cmd->data_length = length;
842 }
843
844 target_complete_cmd(cmd, scsi_status);
845 }
846 EXPORT_SYMBOL(target_complete_cmd_with_length);
847
848 static void target_add_to_state_list(struct se_cmd *cmd)
849 {
850 struct se_device *dev = cmd->se_dev;
851 unsigned long flags;
852
853 spin_lock_irqsave(&dev->execute_task_lock, flags);
854 if (!cmd->state_active) {
855 list_add_tail(&cmd->state_list, &dev->state_list);
856 cmd->state_active = true;
857 }
858 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
859 }
860
861 /*
862 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
863 */
864 static void transport_write_pending_qf(struct se_cmd *cmd);
865 static void transport_complete_qf(struct se_cmd *cmd);
866
867 void target_qf_do_work(struct work_struct *work)
868 {
869 struct se_device *dev = container_of(work, struct se_device,
870 qf_work_queue);
871 LIST_HEAD(qf_cmd_list);
872 struct se_cmd *cmd, *cmd_tmp;
873
874 spin_lock_irq(&dev->qf_cmd_lock);
875 list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
876 spin_unlock_irq(&dev->qf_cmd_lock);
877
878 list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
879 list_del(&cmd->se_qf_node);
880 atomic_dec_mb(&dev->dev_qf_count);
881
882 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
883 " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
884 (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
885 (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
886 : "UNKNOWN");
887
888 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
889 transport_write_pending_qf(cmd);
890 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
891 cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
892 transport_complete_qf(cmd);
893 }
894 }
895
896 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
897 {
898 switch (cmd->data_direction) {
899 case DMA_NONE:
900 return "NONE";
901 case DMA_FROM_DEVICE:
902 return "READ";
903 case DMA_TO_DEVICE:
904 return "WRITE";
905 case DMA_BIDIRECTIONAL:
906 return "BIDI";
907 default:
908 break;
909 }
910
911 return "UNKNOWN";
912 }
913
914 void transport_dump_dev_state(
915 struct se_device *dev,
916 char *b,
917 int *bl)
918 {
919 *bl += sprintf(b + *bl, "Status: ");
920 if (dev->export_count)
921 *bl += sprintf(b + *bl, "ACTIVATED");
922 else
923 *bl += sprintf(b + *bl, "DEACTIVATED");
924
925 *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
926 *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
927 dev->dev_attrib.block_size,
928 dev->dev_attrib.hw_max_sectors);
929 *bl += sprintf(b + *bl, " ");
930 }
931
932 void transport_dump_vpd_proto_id(
933 struct t10_vpd *vpd,
934 unsigned char *p_buf,
935 int p_buf_len)
936 {
937 unsigned char buf[VPD_TMP_BUF_SIZE];
938 int len;
939
940 memset(buf, 0, VPD_TMP_BUF_SIZE);
941 len = sprintf(buf, "T10 VPD Protocol Identifier: ");
942
943 switch (vpd->protocol_identifier) {
944 case 0x00:
945 sprintf(buf+len, "Fibre Channel\n");
946 break;
947 case 0x10:
948 sprintf(buf+len, "Parallel SCSI\n");
949 break;
950 case 0x20:
951 sprintf(buf+len, "SSA\n");
952 break;
953 case 0x30:
954 sprintf(buf+len, "IEEE 1394\n");
955 break;
956 case 0x40:
957 sprintf(buf+len, "SCSI Remote Direct Memory Access"
958 " Protocol\n");
959 break;
960 case 0x50:
961 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
962 break;
963 case 0x60:
964 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
965 break;
966 case 0x70:
967 sprintf(buf+len, "Automation/Drive Interface Transport"
968 " Protocol\n");
969 break;
970 case 0x80:
971 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
972 break;
973 default:
974 sprintf(buf+len, "Unknown 0x%02x\n",
975 vpd->protocol_identifier);
976 break;
977 }
978
979 if (p_buf)
980 strncpy(p_buf, buf, p_buf_len);
981 else
982 pr_debug("%s", buf);
983 }
984
985 void
986 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
987 {
988 /*
989 * Check if the Protocol Identifier Valid (PIV) bit is set..
990 *
991 * from spc3r23.pdf section 7.5.1
992 */
993 if (page_83[1] & 0x80) {
994 vpd->protocol_identifier = (page_83[0] & 0xf0);
995 vpd->protocol_identifier_set = 1;
996 transport_dump_vpd_proto_id(vpd, NULL, 0);
997 }
998 }
999 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1000
1001 int transport_dump_vpd_assoc(
1002 struct t10_vpd *vpd,
1003 unsigned char *p_buf,
1004 int p_buf_len)
1005 {
1006 unsigned char buf[VPD_TMP_BUF_SIZE];
1007 int ret = 0;
1008 int len;
1009
1010 memset(buf, 0, VPD_TMP_BUF_SIZE);
1011 len = sprintf(buf, "T10 VPD Identifier Association: ");
1012
1013 switch (vpd->association) {
1014 case 0x00:
1015 sprintf(buf+len, "addressed logical unit\n");
1016 break;
1017 case 0x10:
1018 sprintf(buf+len, "target port\n");
1019 break;
1020 case 0x20:
1021 sprintf(buf+len, "SCSI target device\n");
1022 break;
1023 default:
1024 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1025 ret = -EINVAL;
1026 break;
1027 }
1028
1029 if (p_buf)
1030 strncpy(p_buf, buf, p_buf_len);
1031 else
1032 pr_debug("%s", buf);
1033
1034 return ret;
1035 }
1036
1037 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1038 {
1039 /*
1040 * The VPD identification association..
1041 *
1042 * from spc3r23.pdf Section 7.6.3.1 Table 297
1043 */
1044 vpd->association = (page_83[1] & 0x30);
1045 return transport_dump_vpd_assoc(vpd, NULL, 0);
1046 }
1047 EXPORT_SYMBOL(transport_set_vpd_assoc);
1048
1049 int transport_dump_vpd_ident_type(
1050 struct t10_vpd *vpd,
1051 unsigned char *p_buf,
1052 int p_buf_len)
1053 {
1054 unsigned char buf[VPD_TMP_BUF_SIZE];
1055 int ret = 0;
1056 int len;
1057
1058 memset(buf, 0, VPD_TMP_BUF_SIZE);
1059 len = sprintf(buf, "T10 VPD Identifier Type: ");
1060
1061 switch (vpd->device_identifier_type) {
1062 case 0x00:
1063 sprintf(buf+len, "Vendor specific\n");
1064 break;
1065 case 0x01:
1066 sprintf(buf+len, "T10 Vendor ID based\n");
1067 break;
1068 case 0x02:
1069 sprintf(buf+len, "EUI-64 based\n");
1070 break;
1071 case 0x03:
1072 sprintf(buf+len, "NAA\n");
1073 break;
1074 case 0x04:
1075 sprintf(buf+len, "Relative target port identifier\n");
1076 break;
1077 case 0x08:
1078 sprintf(buf+len, "SCSI name string\n");
1079 break;
1080 default:
1081 sprintf(buf+len, "Unsupported: 0x%02x\n",
1082 vpd->device_identifier_type);
1083 ret = -EINVAL;
1084 break;
1085 }
1086
1087 if (p_buf) {
1088 if (p_buf_len < strlen(buf)+1)
1089 return -EINVAL;
1090 strncpy(p_buf, buf, p_buf_len);
1091 } else {
1092 pr_debug("%s", buf);
1093 }
1094
1095 return ret;
1096 }
1097
1098 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1099 {
1100 /*
1101 * The VPD identifier type..
1102 *
1103 * from spc3r23.pdf Section 7.6.3.1 Table 298
1104 */
1105 vpd->device_identifier_type = (page_83[1] & 0x0f);
1106 return transport_dump_vpd_ident_type(vpd, NULL, 0);
1107 }
1108 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1109
1110 int transport_dump_vpd_ident(
1111 struct t10_vpd *vpd,
1112 unsigned char *p_buf,
1113 int p_buf_len)
1114 {
1115 unsigned char buf[VPD_TMP_BUF_SIZE];
1116 int ret = 0;
1117
1118 memset(buf, 0, VPD_TMP_BUF_SIZE);
1119
1120 switch (vpd->device_identifier_code_set) {
1121 case 0x01: /* Binary */
1122 snprintf(buf, sizeof(buf),
1123 "T10 VPD Binary Device Identifier: %s\n",
1124 &vpd->device_identifier[0]);
1125 break;
1126 case 0x02: /* ASCII */
1127 snprintf(buf, sizeof(buf),
1128 "T10 VPD ASCII Device Identifier: %s\n",
1129 &vpd->device_identifier[0]);
1130 break;
1131 case 0x03: /* UTF-8 */
1132 snprintf(buf, sizeof(buf),
1133 "T10 VPD UTF-8 Device Identifier: %s\n",
1134 &vpd->device_identifier[0]);
1135 break;
1136 default:
1137 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1138 " 0x%02x", vpd->device_identifier_code_set);
1139 ret = -EINVAL;
1140 break;
1141 }
1142
1143 if (p_buf)
1144 strncpy(p_buf, buf, p_buf_len);
1145 else
1146 pr_debug("%s", buf);
1147
1148 return ret;
1149 }
1150
1151 int
1152 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1153 {
1154 static const char hex_str[] = "0123456789abcdef";
1155 int j = 0, i = 4; /* offset to start of the identifier */
1156
1157 /*
1158 * The VPD Code Set (encoding)
1159 *
1160 * from spc3r23.pdf Section 7.6.3.1 Table 296
1161 */
1162 vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1163 switch (vpd->device_identifier_code_set) {
1164 case 0x01: /* Binary */
1165 vpd->device_identifier[j++] =
1166 hex_str[vpd->device_identifier_type];
1167 while (i < (4 + page_83[3])) {
1168 vpd->device_identifier[j++] =
1169 hex_str[(page_83[i] & 0xf0) >> 4];
1170 vpd->device_identifier[j++] =
1171 hex_str[page_83[i] & 0x0f];
1172 i++;
1173 }
1174 break;
1175 case 0x02: /* ASCII */
1176 case 0x03: /* UTF-8 */
1177 while (i < (4 + page_83[3]))
1178 vpd->device_identifier[j++] = page_83[i++];
1179 break;
1180 default:
1181 break;
1182 }
1183
1184 return transport_dump_vpd_ident(vpd, NULL, 0);
1185 }
1186 EXPORT_SYMBOL(transport_set_vpd_ident);
1187
1188 static sense_reason_t
1189 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1190 unsigned int size)
1191 {
1192 u32 mtl;
1193
1194 if (!cmd->se_tfo->max_data_sg_nents)
1195 return TCM_NO_SENSE;
1196 /*
1197 * Check if fabric enforced maximum SGL entries per I/O descriptor
1198 * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT +
1199 * residual_count and reduce original cmd->data_length to maximum
1200 * length based on single PAGE_SIZE entry scatter-lists.
1201 */
1202 mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1203 if (cmd->data_length > mtl) {
1204 /*
1205 * If an existing CDB overflow is present, calculate new residual
1206 * based on CDB size minus fabric maximum transfer length.
1207 *
1208 * If an existing CDB underflow is present, calculate new residual
1209 * based on original cmd->data_length minus fabric maximum transfer
1210 * length.
1211 *
1212 * Otherwise, set the underflow residual based on cmd->data_length
1213 * minus fabric maximum transfer length.
1214 */
1215 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1216 cmd->residual_count = (size - mtl);
1217 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1218 u32 orig_dl = size + cmd->residual_count;
1219 cmd->residual_count = (orig_dl - mtl);
1220 } else {
1221 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1222 cmd->residual_count = (cmd->data_length - mtl);
1223 }
1224 cmd->data_length = mtl;
1225 /*
1226 * Reset sbc_check_prot() calculated protection payload
1227 * length based upon the new smaller MTL.
1228 */
1229 if (cmd->prot_length) {
1230 u32 sectors = (mtl / dev->dev_attrib.block_size);
1231 cmd->prot_length = dev->prot_length * sectors;
1232 }
1233 }
1234 return TCM_NO_SENSE;
1235 }
1236
1237 sense_reason_t
1238 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1239 {
1240 struct se_device *dev = cmd->se_dev;
1241
1242 if (cmd->unknown_data_length) {
1243 cmd->data_length = size;
1244 } else if (size != cmd->data_length) {
1245 pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1246 " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1247 " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1248 cmd->data_length, size, cmd->t_task_cdb[0]);
1249
1250 if (cmd->data_direction == DMA_TO_DEVICE) {
1251 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1252 pr_err_ratelimited("Rejecting underflow/overflow"
1253 " for WRITE data CDB\n");
1254 return TCM_INVALID_CDB_FIELD;
1255 }
1256 /*
1257 * Some fabric drivers like iscsi-target still expect to
1258 * always reject overflow writes. Reject this case until
1259 * full fabric driver level support for overflow writes
1260 * is introduced tree-wide.
1261 */
1262 if (size > cmd->data_length) {
1263 pr_err_ratelimited("Rejecting overflow for"
1264 " WRITE control CDB\n");
1265 return TCM_INVALID_CDB_FIELD;
1266 }
1267 }
1268 /*
1269 * Reject READ_* or WRITE_* with overflow/underflow for
1270 * type SCF_SCSI_DATA_CDB.
1271 */
1272 if (dev->dev_attrib.block_size != 512) {
1273 pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1274 " CDB on non 512-byte sector setup subsystem"
1275 " plugin: %s\n", dev->transport->name);
1276 /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1277 return TCM_INVALID_CDB_FIELD;
1278 }
1279 /*
1280 * For the overflow case keep the existing fabric provided
1281 * ->data_length. Otherwise for the underflow case, reset
1282 * ->data_length to the smaller SCSI expected data transfer
1283 * length.
1284 */
1285 if (size > cmd->data_length) {
1286 cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1287 cmd->residual_count = (size - cmd->data_length);
1288 } else {
1289 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1290 cmd->residual_count = (cmd->data_length - size);
1291 cmd->data_length = size;
1292 }
1293 }
1294
1295 return target_check_max_data_sg_nents(cmd, dev, size);
1296
1297 }
1298
1299 /*
1300 * Used by fabric modules containing a local struct se_cmd within their
1301 * fabric dependent per I/O descriptor.
1302 *
1303 * Preserves the value of @cmd->tag.
1304 */
1305 void transport_init_se_cmd(
1306 struct se_cmd *cmd,
1307 const struct target_core_fabric_ops *tfo,
1308 struct se_session *se_sess,
1309 u32 data_length,
1310 int data_direction,
1311 int task_attr,
1312 unsigned char *sense_buffer)
1313 {
1314 INIT_LIST_HEAD(&cmd->se_delayed_node);
1315 INIT_LIST_HEAD(&cmd->se_qf_node);
1316 INIT_LIST_HEAD(&cmd->se_cmd_list);
1317 INIT_LIST_HEAD(&cmd->state_list);
1318 init_completion(&cmd->t_transport_stop_comp);
1319 cmd->compl = NULL;
1320 spin_lock_init(&cmd->t_state_lock);
1321 INIT_WORK(&cmd->work, NULL);
1322 kref_init(&cmd->cmd_kref);
1323
1324 cmd->se_tfo = tfo;
1325 cmd->se_sess = se_sess;
1326 cmd->data_length = data_length;
1327 cmd->data_direction = data_direction;
1328 cmd->sam_task_attr = task_attr;
1329 cmd->sense_buffer = sense_buffer;
1330
1331 cmd->state_active = false;
1332 }
1333 EXPORT_SYMBOL(transport_init_se_cmd);
1334
1335 static sense_reason_t
1336 transport_check_alloc_task_attr(struct se_cmd *cmd)
1337 {
1338 struct se_device *dev = cmd->se_dev;
1339
1340 /*
1341 * Check if SAM Task Attribute emulation is enabled for this
1342 * struct se_device storage object
1343 */
1344 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1345 return 0;
1346
1347 if (cmd->sam_task_attr == TCM_ACA_TAG) {
1348 pr_debug("SAM Task Attribute ACA"
1349 " emulation is not supported\n");
1350 return TCM_INVALID_CDB_FIELD;
1351 }
1352
1353 return 0;
1354 }
1355
1356 sense_reason_t
1357 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1358 {
1359 struct se_device *dev = cmd->se_dev;
1360 sense_reason_t ret;
1361
1362 /*
1363 * Ensure that the received CDB is less than the max (252 + 8) bytes
1364 * for VARIABLE_LENGTH_CMD
1365 */
1366 if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1367 pr_err("Received SCSI CDB with command_size: %d that"
1368 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1369 scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1370 return TCM_INVALID_CDB_FIELD;
1371 }
1372 /*
1373 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1374 * allocate the additional extended CDB buffer now.. Otherwise
1375 * setup the pointer from __t_task_cdb to t_task_cdb.
1376 */
1377 if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1378 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1379 GFP_KERNEL);
1380 if (!cmd->t_task_cdb) {
1381 pr_err("Unable to allocate cmd->t_task_cdb"
1382 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1383 scsi_command_size(cdb),
1384 (unsigned long)sizeof(cmd->__t_task_cdb));
1385 return TCM_OUT_OF_RESOURCES;
1386 }
1387 } else
1388 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1389 /*
1390 * Copy the original CDB into cmd->
1391 */
1392 memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1393
1394 trace_target_sequencer_start(cmd);
1395
1396 ret = dev->transport->parse_cdb(cmd);
1397 if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1398 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1399 cmd->se_tfo->get_fabric_name(),
1400 cmd->se_sess->se_node_acl->initiatorname,
1401 cmd->t_task_cdb[0]);
1402 if (ret)
1403 return ret;
1404
1405 ret = transport_check_alloc_task_attr(cmd);
1406 if (ret)
1407 return ret;
1408
1409 cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1410 atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1411 return 0;
1412 }
1413 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1414
1415 /*
1416 * Used by fabric module frontends to queue tasks directly.
1417 * May only be used from process context.
1418 */
1419 int transport_handle_cdb_direct(
1420 struct se_cmd *cmd)
1421 {
1422 sense_reason_t ret;
1423
1424 if (!cmd->se_lun) {
1425 dump_stack();
1426 pr_err("cmd->se_lun is NULL\n");
1427 return -EINVAL;
1428 }
1429 if (in_interrupt()) {
1430 dump_stack();
1431 pr_err("transport_generic_handle_cdb cannot be called"
1432 " from interrupt context\n");
1433 return -EINVAL;
1434 }
1435 /*
1436 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1437 * outstanding descriptors are handled correctly during shutdown via
1438 * transport_wait_for_tasks()
1439 *
1440 * Also, we don't take cmd->t_state_lock here as we only expect
1441 * this to be called for initial descriptor submission.
1442 */
1443 cmd->t_state = TRANSPORT_NEW_CMD;
1444 cmd->transport_state |= CMD_T_ACTIVE;
1445
1446 /*
1447 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1448 * so follow TRANSPORT_NEW_CMD processing thread context usage
1449 * and call transport_generic_request_failure() if necessary..
1450 */
1451 ret = transport_generic_new_cmd(cmd);
1452 if (ret)
1453 transport_generic_request_failure(cmd, ret);
1454 return 0;
1455 }
1456 EXPORT_SYMBOL(transport_handle_cdb_direct);
1457
1458 sense_reason_t
1459 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1460 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1461 {
1462 if (!sgl || !sgl_count)
1463 return 0;
1464
1465 /*
1466 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1467 * scatterlists already have been set to follow what the fabric
1468 * passes for the original expected data transfer length.
1469 */
1470 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1471 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1472 " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1473 return TCM_INVALID_CDB_FIELD;
1474 }
1475
1476 cmd->t_data_sg = sgl;
1477 cmd->t_data_nents = sgl_count;
1478 cmd->t_bidi_data_sg = sgl_bidi;
1479 cmd->t_bidi_data_nents = sgl_bidi_count;
1480
1481 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1482 return 0;
1483 }
1484
1485 /**
1486 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1487 * se_cmd + use pre-allocated SGL memory.
1488 *
1489 * @se_cmd: command descriptor to submit
1490 * @se_sess: associated se_sess for endpoint
1491 * @cdb: pointer to SCSI CDB
1492 * @sense: pointer to SCSI sense buffer
1493 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1494 * @data_length: fabric expected data transfer length
1495 * @task_attr: SAM task attribute
1496 * @data_dir: DMA data direction
1497 * @flags: flags for command submission from target_sc_flags_tables
1498 * @sgl: struct scatterlist memory for unidirectional mapping
1499 * @sgl_count: scatterlist count for unidirectional mapping
1500 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1501 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1502 * @sgl_prot: struct scatterlist memory protection information
1503 * @sgl_prot_count: scatterlist count for protection information
1504 *
1505 * Task tags are supported if the caller has set @se_cmd->tag.
1506 *
1507 * Returns non zero to signal active I/O shutdown failure. All other
1508 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1509 * but still return zero here.
1510 *
1511 * This may only be called from process context, and also currently
1512 * assumes internal allocation of fabric payload buffer by target-core.
1513 */
1514 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1515 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1516 u32 data_length, int task_attr, int data_dir, int flags,
1517 struct scatterlist *sgl, u32 sgl_count,
1518 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1519 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1520 {
1521 struct se_portal_group *se_tpg;
1522 sense_reason_t rc;
1523 int ret;
1524
1525 se_tpg = se_sess->se_tpg;
1526 BUG_ON(!se_tpg);
1527 BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1528 BUG_ON(in_interrupt());
1529 /*
1530 * Initialize se_cmd for target operation. From this point
1531 * exceptions are handled by sending exception status via
1532 * target_core_fabric_ops->queue_status() callback
1533 */
1534 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1535 data_length, data_dir, task_attr, sense);
1536
1537 if (flags & TARGET_SCF_USE_CPUID)
1538 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1539 else
1540 se_cmd->cpuid = WORK_CPU_UNBOUND;
1541
1542 if (flags & TARGET_SCF_UNKNOWN_SIZE)
1543 se_cmd->unknown_data_length = 1;
1544 /*
1545 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1546 * se_sess->sess_cmd_list. A second kref_get here is necessary
1547 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1548 * kref_put() to happen during fabric packet acknowledgement.
1549 */
1550 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1551 if (ret)
1552 return ret;
1553 /*
1554 * Signal bidirectional data payloads to target-core
1555 */
1556 if (flags & TARGET_SCF_BIDI_OP)
1557 se_cmd->se_cmd_flags |= SCF_BIDI;
1558 /*
1559 * Locate se_lun pointer and attach it to struct se_cmd
1560 */
1561 rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1562 if (rc) {
1563 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1564 target_put_sess_cmd(se_cmd);
1565 return 0;
1566 }
1567
1568 rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1569 if (rc != 0) {
1570 transport_generic_request_failure(se_cmd, rc);
1571 return 0;
1572 }
1573
1574 /*
1575 * Save pointers for SGLs containing protection information,
1576 * if present.
1577 */
1578 if (sgl_prot_count) {
1579 se_cmd->t_prot_sg = sgl_prot;
1580 se_cmd->t_prot_nents = sgl_prot_count;
1581 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1582 }
1583
1584 /*
1585 * When a non zero sgl_count has been passed perform SGL passthrough
1586 * mapping for pre-allocated fabric memory instead of having target
1587 * core perform an internal SGL allocation..
1588 */
1589 if (sgl_count != 0) {
1590 BUG_ON(!sgl);
1591
1592 /*
1593 * A work-around for tcm_loop as some userspace code via
1594 * scsi-generic do not memset their associated read buffers,
1595 * so go ahead and do that here for type non-data CDBs. Also
1596 * note that this is currently guaranteed to be a single SGL
1597 * for this case by target core in target_setup_cmd_from_cdb()
1598 * -> transport_generic_cmd_sequencer().
1599 */
1600 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1601 se_cmd->data_direction == DMA_FROM_DEVICE) {
1602 unsigned char *buf = NULL;
1603
1604 if (sgl)
1605 buf = kmap(sg_page(sgl)) + sgl->offset;
1606
1607 if (buf) {
1608 memset(buf, 0, sgl->length);
1609 kunmap(sg_page(sgl));
1610 }
1611 }
1612
1613 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1614 sgl_bidi, sgl_bidi_count);
1615 if (rc != 0) {
1616 transport_generic_request_failure(se_cmd, rc);
1617 return 0;
1618 }
1619 }
1620
1621 /*
1622 * Check if we need to delay processing because of ALUA
1623 * Active/NonOptimized primary access state..
1624 */
1625 core_alua_check_nonop_delay(se_cmd);
1626
1627 transport_handle_cdb_direct(se_cmd);
1628 return 0;
1629 }
1630 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1631
1632 /**
1633 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1634 *
1635 * @se_cmd: command descriptor to submit
1636 * @se_sess: associated se_sess for endpoint
1637 * @cdb: pointer to SCSI CDB
1638 * @sense: pointer to SCSI sense buffer
1639 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1640 * @data_length: fabric expected data transfer length
1641 * @task_attr: SAM task attribute
1642 * @data_dir: DMA data direction
1643 * @flags: flags for command submission from target_sc_flags_tables
1644 *
1645 * Task tags are supported if the caller has set @se_cmd->tag.
1646 *
1647 * Returns non zero to signal active I/O shutdown failure. All other
1648 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1649 * but still return zero here.
1650 *
1651 * This may only be called from process context, and also currently
1652 * assumes internal allocation of fabric payload buffer by target-core.
1653 *
1654 * It also assumes interal target core SGL memory allocation.
1655 */
1656 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1657 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1658 u32 data_length, int task_attr, int data_dir, int flags)
1659 {
1660 return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1661 unpacked_lun, data_length, task_attr, data_dir,
1662 flags, NULL, 0, NULL, 0, NULL, 0);
1663 }
1664 EXPORT_SYMBOL(target_submit_cmd);
1665
1666 static void target_complete_tmr_failure(struct work_struct *work)
1667 {
1668 struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1669
1670 se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1671 se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1672
1673 transport_lun_remove_cmd(se_cmd);
1674 transport_cmd_check_stop_to_fabric(se_cmd);
1675 }
1676
1677 static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
1678 u64 *unpacked_lun)
1679 {
1680 struct se_cmd *se_cmd;
1681 unsigned long flags;
1682 bool ret = false;
1683
1684 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
1685 list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
1686 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1687 continue;
1688
1689 if (se_cmd->tag == tag) {
1690 *unpacked_lun = se_cmd->orig_fe_lun;
1691 ret = true;
1692 break;
1693 }
1694 }
1695 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
1696
1697 return ret;
1698 }
1699
1700 /**
1701 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1702 * for TMR CDBs
1703 *
1704 * @se_cmd: command descriptor to submit
1705 * @se_sess: associated se_sess for endpoint
1706 * @sense: pointer to SCSI sense buffer
1707 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1708 * @fabric_tmr_ptr: fabric context for TMR req
1709 * @tm_type: Type of TM request
1710 * @gfp: gfp type for caller
1711 * @tag: referenced task tag for TMR_ABORT_TASK
1712 * @flags: submit cmd flags
1713 *
1714 * Callable from all contexts.
1715 **/
1716
1717 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1718 unsigned char *sense, u64 unpacked_lun,
1719 void *fabric_tmr_ptr, unsigned char tm_type,
1720 gfp_t gfp, u64 tag, int flags)
1721 {
1722 struct se_portal_group *se_tpg;
1723 int ret;
1724
1725 se_tpg = se_sess->se_tpg;
1726 BUG_ON(!se_tpg);
1727
1728 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1729 0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1730 /*
1731 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1732 * allocation failure.
1733 */
1734 ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1735 if (ret < 0)
1736 return -ENOMEM;
1737
1738 if (tm_type == TMR_ABORT_TASK)
1739 se_cmd->se_tmr_req->ref_task_tag = tag;
1740
1741 /* See target_submit_cmd for commentary */
1742 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1743 if (ret) {
1744 core_tmr_release_req(se_cmd->se_tmr_req);
1745 return ret;
1746 }
1747 /*
1748 * If this is ABORT_TASK with no explicit fabric provided LUN,
1749 * go ahead and search active session tags for a match to figure
1750 * out unpacked_lun for the original se_cmd.
1751 */
1752 if (tm_type == TMR_ABORT_TASK && (flags & TARGET_SCF_LOOKUP_LUN_FROM_TAG)) {
1753 if (!target_lookup_lun_from_tag(se_sess, tag, &unpacked_lun))
1754 goto failure;
1755 }
1756
1757 ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1758 if (ret)
1759 goto failure;
1760
1761 transport_generic_handle_tmr(se_cmd);
1762 return 0;
1763
1764 /*
1765 * For callback during failure handling, push this work off
1766 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1767 */
1768 failure:
1769 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1770 schedule_work(&se_cmd->work);
1771 return 0;
1772 }
1773 EXPORT_SYMBOL(target_submit_tmr);
1774
1775 /*
1776 * Handle SAM-esque emulation for generic transport request failures.
1777 */
1778 void transport_generic_request_failure(struct se_cmd *cmd,
1779 sense_reason_t sense_reason)
1780 {
1781 int ret = 0;
1782
1783 pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
1784 sense_reason);
1785 target_show_cmd("-----[ ", cmd);
1786
1787 /*
1788 * For SAM Task Attribute emulation for failed struct se_cmd
1789 */
1790 transport_complete_task_attr(cmd);
1791
1792 if (cmd->transport_complete_callback)
1793 cmd->transport_complete_callback(cmd, false, NULL);
1794
1795 if (transport_check_aborted_status(cmd, 1))
1796 return;
1797
1798 switch (sense_reason) {
1799 case TCM_NON_EXISTENT_LUN:
1800 case TCM_UNSUPPORTED_SCSI_OPCODE:
1801 case TCM_INVALID_CDB_FIELD:
1802 case TCM_INVALID_PARAMETER_LIST:
1803 case TCM_PARAMETER_LIST_LENGTH_ERROR:
1804 case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1805 case TCM_UNKNOWN_MODE_PAGE:
1806 case TCM_WRITE_PROTECTED:
1807 case TCM_ADDRESS_OUT_OF_RANGE:
1808 case TCM_CHECK_CONDITION_ABORT_CMD:
1809 case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1810 case TCM_CHECK_CONDITION_NOT_READY:
1811 case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1812 case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1813 case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1814 case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1815 case TCM_TOO_MANY_TARGET_DESCS:
1816 case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
1817 case TCM_TOO_MANY_SEGMENT_DESCS:
1818 case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
1819 break;
1820 case TCM_OUT_OF_RESOURCES:
1821 cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
1822 goto queue_status;
1823 case TCM_LUN_BUSY:
1824 cmd->scsi_status = SAM_STAT_BUSY;
1825 goto queue_status;
1826 case TCM_RESERVATION_CONFLICT:
1827 /*
1828 * No SENSE Data payload for this case, set SCSI Status
1829 * and queue the response to $FABRIC_MOD.
1830 *
1831 * Uses linux/include/scsi/scsi.h SAM status codes defs
1832 */
1833 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1834 /*
1835 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1836 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1837 * CONFLICT STATUS.
1838 *
1839 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1840 */
1841 if (cmd->se_sess &&
1842 cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1843 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1844 cmd->orig_fe_lun, 0x2C,
1845 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1846 }
1847
1848 goto queue_status;
1849 default:
1850 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1851 cmd->t_task_cdb[0], sense_reason);
1852 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1853 break;
1854 }
1855
1856 ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1857 if (ret)
1858 goto queue_full;
1859
1860 check_stop:
1861 transport_lun_remove_cmd(cmd);
1862 transport_cmd_check_stop_to_fabric(cmd);
1863 return;
1864
1865 queue_status:
1866 trace_target_cmd_complete(cmd);
1867 ret = cmd->se_tfo->queue_status(cmd);
1868 if (!ret)
1869 goto check_stop;
1870 queue_full:
1871 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
1872 }
1873 EXPORT_SYMBOL(transport_generic_request_failure);
1874
1875 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1876 {
1877 sense_reason_t ret;
1878
1879 if (!cmd->execute_cmd) {
1880 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1881 goto err;
1882 }
1883 if (do_checks) {
1884 /*
1885 * Check for an existing UNIT ATTENTION condition after
1886 * target_handle_task_attr() has done SAM task attr
1887 * checking, and possibly have already defered execution
1888 * out to target_restart_delayed_cmds() context.
1889 */
1890 ret = target_scsi3_ua_check(cmd);
1891 if (ret)
1892 goto err;
1893
1894 ret = target_alua_state_check(cmd);
1895 if (ret)
1896 goto err;
1897
1898 ret = target_check_reservation(cmd);
1899 if (ret) {
1900 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1901 goto err;
1902 }
1903 }
1904
1905 ret = cmd->execute_cmd(cmd);
1906 if (!ret)
1907 return;
1908 err:
1909 spin_lock_irq(&cmd->t_state_lock);
1910 cmd->transport_state &= ~CMD_T_SENT;
1911 spin_unlock_irq(&cmd->t_state_lock);
1912
1913 transport_generic_request_failure(cmd, ret);
1914 }
1915
1916 static int target_write_prot_action(struct se_cmd *cmd)
1917 {
1918 u32 sectors;
1919 /*
1920 * Perform WRITE_INSERT of PI using software emulation when backend
1921 * device has PI enabled, if the transport has not already generated
1922 * PI using hardware WRITE_INSERT offload.
1923 */
1924 switch (cmd->prot_op) {
1925 case TARGET_PROT_DOUT_INSERT:
1926 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1927 sbc_dif_generate(cmd);
1928 break;
1929 case TARGET_PROT_DOUT_STRIP:
1930 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1931 break;
1932
1933 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1934 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1935 sectors, 0, cmd->t_prot_sg, 0);
1936 if (unlikely(cmd->pi_err)) {
1937 spin_lock_irq(&cmd->t_state_lock);
1938 cmd->transport_state &= ~CMD_T_SENT;
1939 spin_unlock_irq(&cmd->t_state_lock);
1940 transport_generic_request_failure(cmd, cmd->pi_err);
1941 return -1;
1942 }
1943 break;
1944 default:
1945 break;
1946 }
1947
1948 return 0;
1949 }
1950
1951 static bool target_handle_task_attr(struct se_cmd *cmd)
1952 {
1953 struct se_device *dev = cmd->se_dev;
1954
1955 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1956 return false;
1957
1958 cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
1959
1960 /*
1961 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1962 * to allow the passed struct se_cmd list of tasks to the front of the list.
1963 */
1964 switch (cmd->sam_task_attr) {
1965 case TCM_HEAD_TAG:
1966 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1967 cmd->t_task_cdb[0]);
1968 return false;
1969 case TCM_ORDERED_TAG:
1970 atomic_inc_mb(&dev->dev_ordered_sync);
1971
1972 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1973 cmd->t_task_cdb[0]);
1974
1975 /*
1976 * Execute an ORDERED command if no other older commands
1977 * exist that need to be completed first.
1978 */
1979 if (!atomic_read(&dev->simple_cmds))
1980 return false;
1981 break;
1982 default:
1983 /*
1984 * For SIMPLE and UNTAGGED Task Attribute commands
1985 */
1986 atomic_inc_mb(&dev->simple_cmds);
1987 break;
1988 }
1989
1990 if (atomic_read(&dev->dev_ordered_sync) == 0)
1991 return false;
1992
1993 spin_lock(&dev->delayed_cmd_lock);
1994 list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1995 spin_unlock(&dev->delayed_cmd_lock);
1996
1997 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
1998 cmd->t_task_cdb[0], cmd->sam_task_attr);
1999 return true;
2000 }
2001
2002 static int __transport_check_aborted_status(struct se_cmd *, int);
2003
2004 void target_execute_cmd(struct se_cmd *cmd)
2005 {
2006 /*
2007 * Determine if frontend context caller is requesting the stopping of
2008 * this command for frontend exceptions.
2009 *
2010 * If the received CDB has already been aborted stop processing it here.
2011 */
2012 spin_lock_irq(&cmd->t_state_lock);
2013 if (__transport_check_aborted_status(cmd, 1)) {
2014 spin_unlock_irq(&cmd->t_state_lock);
2015 return;
2016 }
2017 if (cmd->transport_state & CMD_T_STOP) {
2018 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2019 __func__, __LINE__, cmd->tag);
2020
2021 spin_unlock_irq(&cmd->t_state_lock);
2022 complete_all(&cmd->t_transport_stop_comp);
2023 return;
2024 }
2025
2026 cmd->t_state = TRANSPORT_PROCESSING;
2027 cmd->transport_state &= ~CMD_T_PRE_EXECUTE;
2028 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
2029 spin_unlock_irq(&cmd->t_state_lock);
2030
2031 if (target_write_prot_action(cmd))
2032 return;
2033
2034 if (target_handle_task_attr(cmd)) {
2035 spin_lock_irq(&cmd->t_state_lock);
2036 cmd->transport_state &= ~CMD_T_SENT;
2037 spin_unlock_irq(&cmd->t_state_lock);
2038 return;
2039 }
2040
2041 __target_execute_cmd(cmd, true);
2042 }
2043 EXPORT_SYMBOL(target_execute_cmd);
2044
2045 /*
2046 * Process all commands up to the last received ORDERED task attribute which
2047 * requires another blocking boundary
2048 */
2049 static void target_restart_delayed_cmds(struct se_device *dev)
2050 {
2051 for (;;) {
2052 struct se_cmd *cmd;
2053
2054 spin_lock(&dev->delayed_cmd_lock);
2055 if (list_empty(&dev->delayed_cmd_list)) {
2056 spin_unlock(&dev->delayed_cmd_lock);
2057 break;
2058 }
2059
2060 cmd = list_entry(dev->delayed_cmd_list.next,
2061 struct se_cmd, se_delayed_node);
2062 list_del(&cmd->se_delayed_node);
2063 spin_unlock(&dev->delayed_cmd_lock);
2064
2065 cmd->transport_state |= CMD_T_SENT;
2066
2067 __target_execute_cmd(cmd, true);
2068
2069 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
2070 break;
2071 }
2072 }
2073
2074 /*
2075 * Called from I/O completion to determine which dormant/delayed
2076 * and ordered cmds need to have their tasks added to the execution queue.
2077 */
2078 static void transport_complete_task_attr(struct se_cmd *cmd)
2079 {
2080 struct se_device *dev = cmd->se_dev;
2081
2082 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2083 return;
2084
2085 if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2086 goto restart;
2087
2088 if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
2089 atomic_dec_mb(&dev->simple_cmds);
2090 dev->dev_cur_ordered_id++;
2091 } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
2092 dev->dev_cur_ordered_id++;
2093 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
2094 dev->dev_cur_ordered_id);
2095 } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2096 atomic_dec_mb(&dev->dev_ordered_sync);
2097
2098 dev->dev_cur_ordered_id++;
2099 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
2100 dev->dev_cur_ordered_id);
2101 }
2102 cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2103
2104 restart:
2105 target_restart_delayed_cmds(dev);
2106 }
2107
2108 static void transport_complete_qf(struct se_cmd *cmd)
2109 {
2110 int ret = 0;
2111
2112 transport_complete_task_attr(cmd);
2113 /*
2114 * If a fabric driver ->write_pending() or ->queue_data_in() callback
2115 * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2116 * the same callbacks should not be retried. Return CHECK_CONDITION
2117 * if a scsi_status is not already set.
2118 *
2119 * If a fabric driver ->queue_status() has returned non zero, always
2120 * keep retrying no matter what..
2121 */
2122 if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2123 if (cmd->scsi_status)
2124 goto queue_status;
2125
2126 translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2127 goto queue_status;
2128 }
2129
2130 /*
2131 * Check if we need to send a sense buffer from
2132 * the struct se_cmd in question. We do NOT want
2133 * to take this path of the IO has been marked as
2134 * needing to be treated like a "normal read". This
2135 * is the case if it's a tape read, and either the
2136 * FM, EOM, or ILI bits are set, but there is no
2137 * sense data.
2138 */
2139 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2140 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2141 goto queue_status;
2142
2143 switch (cmd->data_direction) {
2144 case DMA_FROM_DEVICE:
2145 /* queue status if not treating this as a normal read */
2146 if (cmd->scsi_status &&
2147 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2148 goto queue_status;
2149
2150 trace_target_cmd_complete(cmd);
2151 ret = cmd->se_tfo->queue_data_in(cmd);
2152 break;
2153 case DMA_TO_DEVICE:
2154 if (cmd->se_cmd_flags & SCF_BIDI) {
2155 ret = cmd->se_tfo->queue_data_in(cmd);
2156 break;
2157 }
2158 /* fall through */
2159 case DMA_NONE:
2160 queue_status:
2161 trace_target_cmd_complete(cmd);
2162 ret = cmd->se_tfo->queue_status(cmd);
2163 break;
2164 default:
2165 break;
2166 }
2167
2168 if (ret < 0) {
2169 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2170 return;
2171 }
2172 transport_lun_remove_cmd(cmd);
2173 transport_cmd_check_stop_to_fabric(cmd);
2174 }
2175
2176 static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2177 int err, bool write_pending)
2178 {
2179 /*
2180 * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2181 * ->queue_data_in() callbacks from new process context.
2182 *
2183 * Otherwise for other errors, transport_complete_qf() will send
2184 * CHECK_CONDITION via ->queue_status() instead of attempting to
2185 * retry associated fabric driver data-transfer callbacks.
2186 */
2187 if (err == -EAGAIN || err == -ENOMEM) {
2188 cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2189 TRANSPORT_COMPLETE_QF_OK;
2190 } else {
2191 pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2192 cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2193 }
2194
2195 spin_lock_irq(&dev->qf_cmd_lock);
2196 list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2197 atomic_inc_mb(&dev->dev_qf_count);
2198 spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2199
2200 schedule_work(&cmd->se_dev->qf_work_queue);
2201 }
2202
2203 static bool target_read_prot_action(struct se_cmd *cmd)
2204 {
2205 switch (cmd->prot_op) {
2206 case TARGET_PROT_DIN_STRIP:
2207 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2208 u32 sectors = cmd->data_length >>
2209 ilog2(cmd->se_dev->dev_attrib.block_size);
2210
2211 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2212 sectors, 0, cmd->t_prot_sg,
2213 0);
2214 if (cmd->pi_err)
2215 return true;
2216 }
2217 break;
2218 case TARGET_PROT_DIN_INSERT:
2219 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2220 break;
2221
2222 sbc_dif_generate(cmd);
2223 break;
2224 default:
2225 break;
2226 }
2227
2228 return false;
2229 }
2230
2231 static void target_complete_ok_work(struct work_struct *work)
2232 {
2233 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2234 int ret;
2235
2236 /*
2237 * Check if we need to move delayed/dormant tasks from cmds on the
2238 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2239 * Attribute.
2240 */
2241 transport_complete_task_attr(cmd);
2242
2243 /*
2244 * Check to schedule QUEUE_FULL work, or execute an existing
2245 * cmd->transport_qf_callback()
2246 */
2247 if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2248 schedule_work(&cmd->se_dev->qf_work_queue);
2249
2250 /*
2251 * Check if we need to send a sense buffer from
2252 * the struct se_cmd in question. We do NOT want
2253 * to take this path of the IO has been marked as
2254 * needing to be treated like a "normal read". This
2255 * is the case if it's a tape read, and either the
2256 * FM, EOM, or ILI bits are set, but there is no
2257 * sense data.
2258 */
2259 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2260 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2261 WARN_ON(!cmd->scsi_status);
2262 ret = transport_send_check_condition_and_sense(
2263 cmd, 0, 1);
2264 if (ret)
2265 goto queue_full;
2266
2267 transport_lun_remove_cmd(cmd);
2268 transport_cmd_check_stop_to_fabric(cmd);
2269 return;
2270 }
2271 /*
2272 * Check for a callback, used by amongst other things
2273 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2274 */
2275 if (cmd->transport_complete_callback) {
2276 sense_reason_t rc;
2277 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2278 bool zero_dl = !(cmd->data_length);
2279 int post_ret = 0;
2280
2281 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2282 if (!rc && !post_ret) {
2283 if (caw && zero_dl)
2284 goto queue_rsp;
2285
2286 return;
2287 } else if (rc) {
2288 ret = transport_send_check_condition_and_sense(cmd,
2289 rc, 0);
2290 if (ret)
2291 goto queue_full;
2292
2293 transport_lun_remove_cmd(cmd);
2294 transport_cmd_check_stop_to_fabric(cmd);
2295 return;
2296 }
2297 }
2298
2299 queue_rsp:
2300 switch (cmd->data_direction) {
2301 case DMA_FROM_DEVICE:
2302 /*
2303 * if this is a READ-type IO, but SCSI status
2304 * is set, then skip returning data and just
2305 * return the status -- unless this IO is marked
2306 * as needing to be treated as a normal read,
2307 * in which case we want to go ahead and return
2308 * the data. This happens, for example, for tape
2309 * reads with the FM, EOM, or ILI bits set, with
2310 * no sense data.
2311 */
2312 if (cmd->scsi_status &&
2313 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2314 goto queue_status;
2315
2316 atomic_long_add(cmd->data_length,
2317 &cmd->se_lun->lun_stats.tx_data_octets);
2318 /*
2319 * Perform READ_STRIP of PI using software emulation when
2320 * backend had PI enabled, if the transport will not be
2321 * performing hardware READ_STRIP offload.
2322 */
2323 if (target_read_prot_action(cmd)) {
2324 ret = transport_send_check_condition_and_sense(cmd,
2325 cmd->pi_err, 0);
2326 if (ret)
2327 goto queue_full;
2328
2329 transport_lun_remove_cmd(cmd);
2330 transport_cmd_check_stop_to_fabric(cmd);
2331 return;
2332 }
2333
2334 trace_target_cmd_complete(cmd);
2335 ret = cmd->se_tfo->queue_data_in(cmd);
2336 if (ret)
2337 goto queue_full;
2338 break;
2339 case DMA_TO_DEVICE:
2340 atomic_long_add(cmd->data_length,
2341 &cmd->se_lun->lun_stats.rx_data_octets);
2342 /*
2343 * Check if we need to send READ payload for BIDI-COMMAND
2344 */
2345 if (cmd->se_cmd_flags & SCF_BIDI) {
2346 atomic_long_add(cmd->data_length,
2347 &cmd->se_lun->lun_stats.tx_data_octets);
2348 ret = cmd->se_tfo->queue_data_in(cmd);
2349 if (ret)
2350 goto queue_full;
2351 break;
2352 }
2353 /* fall through */
2354 case DMA_NONE:
2355 queue_status:
2356 trace_target_cmd_complete(cmd);
2357 ret = cmd->se_tfo->queue_status(cmd);
2358 if (ret)
2359 goto queue_full;
2360 break;
2361 default:
2362 break;
2363 }
2364
2365 transport_lun_remove_cmd(cmd);
2366 transport_cmd_check_stop_to_fabric(cmd);
2367 return;
2368
2369 queue_full:
2370 pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2371 " data_direction: %d\n", cmd, cmd->data_direction);
2372
2373 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2374 }
2375
2376 void target_free_sgl(struct scatterlist *sgl, int nents)
2377 {
2378 sgl_free_n_order(sgl, nents, 0);
2379 }
2380 EXPORT_SYMBOL(target_free_sgl);
2381
2382 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2383 {
2384 /*
2385 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2386 * emulation, and free + reset pointers if necessary..
2387 */
2388 if (!cmd->t_data_sg_orig)
2389 return;
2390
2391 kfree(cmd->t_data_sg);
2392 cmd->t_data_sg = cmd->t_data_sg_orig;
2393 cmd->t_data_sg_orig = NULL;
2394 cmd->t_data_nents = cmd->t_data_nents_orig;
2395 cmd->t_data_nents_orig = 0;
2396 }
2397
2398 static inline void transport_free_pages(struct se_cmd *cmd)
2399 {
2400 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2401 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2402 cmd->t_prot_sg = NULL;
2403 cmd->t_prot_nents = 0;
2404 }
2405
2406 if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2407 /*
2408 * Release special case READ buffer payload required for
2409 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2410 */
2411 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2412 target_free_sgl(cmd->t_bidi_data_sg,
2413 cmd->t_bidi_data_nents);
2414 cmd->t_bidi_data_sg = NULL;
2415 cmd->t_bidi_data_nents = 0;
2416 }
2417 transport_reset_sgl_orig(cmd);
2418 return;
2419 }
2420 transport_reset_sgl_orig(cmd);
2421
2422 target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2423 cmd->t_data_sg = NULL;
2424 cmd->t_data_nents = 0;
2425
2426 target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2427 cmd->t_bidi_data_sg = NULL;
2428 cmd->t_bidi_data_nents = 0;
2429 }
2430
2431 void *transport_kmap_data_sg(struct se_cmd *cmd)
2432 {
2433 struct scatterlist *sg = cmd->t_data_sg;
2434 struct page **pages;
2435 int i;
2436
2437 /*
2438 * We need to take into account a possible offset here for fabrics like
2439 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2440 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2441 */
2442 if (!cmd->t_data_nents)
2443 return NULL;
2444
2445 BUG_ON(!sg);
2446 if (cmd->t_data_nents == 1)
2447 return kmap(sg_page(sg)) + sg->offset;
2448
2449 /* >1 page. use vmap */
2450 pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2451 if (!pages)
2452 return NULL;
2453
2454 /* convert sg[] to pages[] */
2455 for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2456 pages[i] = sg_page(sg);
2457 }
2458
2459 cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
2460 kfree(pages);
2461 if (!cmd->t_data_vmap)
2462 return NULL;
2463
2464 return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2465 }
2466 EXPORT_SYMBOL(transport_kmap_data_sg);
2467
2468 void transport_kunmap_data_sg(struct se_cmd *cmd)
2469 {
2470 if (!cmd->t_data_nents) {
2471 return;
2472 } else if (cmd->t_data_nents == 1) {
2473 kunmap(sg_page(cmd->t_data_sg));
2474 return;
2475 }
2476
2477 vunmap(cmd->t_data_vmap);
2478 cmd->t_data_vmap = NULL;
2479 }
2480 EXPORT_SYMBOL(transport_kunmap_data_sg);
2481
2482 int
2483 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2484 bool zero_page, bool chainable)
2485 {
2486 gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2487
2488 *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2489 return *sgl ? 0 : -ENOMEM;
2490 }
2491 EXPORT_SYMBOL(target_alloc_sgl);
2492
2493 /*
2494 * Allocate any required resources to execute the command. For writes we
2495 * might not have the payload yet, so notify the fabric via a call to
2496 * ->write_pending instead. Otherwise place it on the execution queue.
2497 */
2498 sense_reason_t
2499 transport_generic_new_cmd(struct se_cmd *cmd)
2500 {
2501 unsigned long flags;
2502 int ret = 0;
2503 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2504
2505 if (cmd->prot_op != TARGET_PROT_NORMAL &&
2506 !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2507 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2508 cmd->prot_length, true, false);
2509 if (ret < 0)
2510 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2511 }
2512
2513 /*
2514 * Determine if the TCM fabric module has already allocated physical
2515 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2516 * beforehand.
2517 */
2518 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2519 cmd->data_length) {
2520
2521 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2522 (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2523 u32 bidi_length;
2524
2525 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2526 bidi_length = cmd->t_task_nolb *
2527 cmd->se_dev->dev_attrib.block_size;
2528 else
2529 bidi_length = cmd->data_length;
2530
2531 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2532 &cmd->t_bidi_data_nents,
2533 bidi_length, zero_flag, false);
2534 if (ret < 0)
2535 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2536 }
2537
2538 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2539 cmd->data_length, zero_flag, false);
2540 if (ret < 0)
2541 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2542 } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2543 cmd->data_length) {
2544 /*
2545 * Special case for COMPARE_AND_WRITE with fabrics
2546 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2547 */
2548 u32 caw_length = cmd->t_task_nolb *
2549 cmd->se_dev->dev_attrib.block_size;
2550
2551 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2552 &cmd->t_bidi_data_nents,
2553 caw_length, zero_flag, false);
2554 if (ret < 0)
2555 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2556 }
2557 /*
2558 * If this command is not a write we can execute it right here,
2559 * for write buffers we need to notify the fabric driver first
2560 * and let it call back once the write buffers are ready.
2561 */
2562 target_add_to_state_list(cmd);
2563 if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2564 target_execute_cmd(cmd);
2565 return 0;
2566 }
2567
2568 spin_lock_irqsave(&cmd->t_state_lock, flags);
2569 cmd->t_state = TRANSPORT_WRITE_PENDING;
2570 /*
2571 * Determine if frontend context caller is requesting the stopping of
2572 * this command for frontend exceptions.
2573 */
2574 if (cmd->transport_state & CMD_T_STOP) {
2575 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2576 __func__, __LINE__, cmd->tag);
2577
2578 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2579
2580 complete_all(&cmd->t_transport_stop_comp);
2581 return 0;
2582 }
2583 cmd->transport_state &= ~CMD_T_ACTIVE;
2584 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2585
2586 ret = cmd->se_tfo->write_pending(cmd);
2587 if (ret)
2588 goto queue_full;
2589
2590 return 0;
2591
2592 queue_full:
2593 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2594 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2595 return 0;
2596 }
2597 EXPORT_SYMBOL(transport_generic_new_cmd);
2598
2599 static void transport_write_pending_qf(struct se_cmd *cmd)
2600 {
2601 unsigned long flags;
2602 int ret;
2603 bool stop;
2604
2605 spin_lock_irqsave(&cmd->t_state_lock, flags);
2606 stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2607 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2608
2609 if (stop) {
2610 pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2611 __func__, __LINE__, cmd->tag);
2612 complete_all(&cmd->t_transport_stop_comp);
2613 return;
2614 }
2615
2616 ret = cmd->se_tfo->write_pending(cmd);
2617 if (ret) {
2618 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2619 cmd);
2620 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2621 }
2622 }
2623
2624 static bool
2625 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2626 unsigned long *flags);
2627
2628 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2629 {
2630 unsigned long flags;
2631
2632 spin_lock_irqsave(&cmd->t_state_lock, flags);
2633 __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2634 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2635 }
2636
2637 /*
2638 * This function is called by frontend drivers after processing of a command
2639 * has finished.
2640 *
2641 * The protocol for ensuring that either the regular flow or the TMF
2642 * code drops one reference is as follows:
2643 * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
2644 * the frontend driver to drop one reference, synchronously or asynchronously.
2645 * - During regular command processing the target core sets CMD_T_COMPLETE
2646 * before invoking one of the .queue_*() functions.
2647 * - The code that aborts commands skips commands and TMFs for which
2648 * CMD_T_COMPLETE has been set.
2649 * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
2650 * commands that will be aborted.
2651 * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
2652 * transport_generic_free_cmd() skips its call to target_put_sess_cmd().
2653 * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
2654 * be called and will drop a reference.
2655 * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
2656 * will be called. transport_cmd_finish_abort() will drop the final reference.
2657 */
2658 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2659 {
2660 DECLARE_COMPLETION_ONSTACK(compl);
2661 int ret = 0;
2662 bool aborted = false, tas = false;
2663
2664 if (wait_for_tasks)
2665 target_wait_free_cmd(cmd, &aborted, &tas);
2666
2667 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
2668 /*
2669 * Handle WRITE failure case where transport_generic_new_cmd()
2670 * has already added se_cmd to state_list, but fabric has
2671 * failed command before I/O submission.
2672 */
2673 if (cmd->state_active)
2674 target_remove_from_state_list(cmd);
2675
2676 if (cmd->se_lun)
2677 transport_lun_remove_cmd(cmd);
2678 }
2679 if (aborted)
2680 cmd->compl = &compl;
2681 if (!aborted || tas)
2682 ret = target_put_sess_cmd(cmd);
2683 if (aborted) {
2684 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2685 wait_for_completion(&compl);
2686 ret = 1;
2687 }
2688 return ret;
2689 }
2690 EXPORT_SYMBOL(transport_generic_free_cmd);
2691
2692 /**
2693 * target_get_sess_cmd - Add command to active ->sess_cmd_list
2694 * @se_cmd: command descriptor to add
2695 * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
2696 */
2697 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2698 {
2699 struct se_session *se_sess = se_cmd->se_sess;
2700 unsigned long flags;
2701 int ret = 0;
2702
2703 /*
2704 * Add a second kref if the fabric caller is expecting to handle
2705 * fabric acknowledgement that requires two target_put_sess_cmd()
2706 * invocations before se_cmd descriptor release.
2707 */
2708 if (ack_kref) {
2709 if (!kref_get_unless_zero(&se_cmd->cmd_kref))
2710 return -EINVAL;
2711
2712 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2713 }
2714
2715 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2716 if (se_sess->sess_tearing_down) {
2717 ret = -ESHUTDOWN;
2718 goto out;
2719 }
2720 se_cmd->transport_state |= CMD_T_PRE_EXECUTE;
2721 list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2722 out:
2723 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2724
2725 if (ret && ack_kref)
2726 target_put_sess_cmd(se_cmd);
2727
2728 return ret;
2729 }
2730 EXPORT_SYMBOL(target_get_sess_cmd);
2731
2732 static void target_free_cmd_mem(struct se_cmd *cmd)
2733 {
2734 transport_free_pages(cmd);
2735
2736 if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2737 core_tmr_release_req(cmd->se_tmr_req);
2738 if (cmd->t_task_cdb != cmd->__t_task_cdb)
2739 kfree(cmd->t_task_cdb);
2740 }
2741
2742 static void target_release_cmd_kref(struct kref *kref)
2743 {
2744 struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2745 struct se_session *se_sess = se_cmd->se_sess;
2746 struct completion *compl = se_cmd->compl;
2747 unsigned long flags;
2748
2749 if (se_sess) {
2750 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2751 list_del_init(&se_cmd->se_cmd_list);
2752 if (se_sess->sess_tearing_down && list_empty(&se_sess->sess_cmd_list))
2753 wake_up(&se_sess->cmd_list_wq);
2754 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2755 }
2756
2757 target_free_cmd_mem(se_cmd);
2758 se_cmd->se_tfo->release_cmd(se_cmd);
2759 if (compl)
2760 complete(compl);
2761 }
2762
2763 /**
2764 * target_put_sess_cmd - decrease the command reference count
2765 * @se_cmd: command to drop a reference from
2766 *
2767 * Returns 1 if and only if this target_put_sess_cmd() call caused the
2768 * refcount to drop to zero. Returns zero otherwise.
2769 */
2770 int target_put_sess_cmd(struct se_cmd *se_cmd)
2771 {
2772 return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2773 }
2774 EXPORT_SYMBOL(target_put_sess_cmd);
2775
2776 static const char *data_dir_name(enum dma_data_direction d)
2777 {
2778 switch (d) {
2779 case DMA_BIDIRECTIONAL: return "BIDI";
2780 case DMA_TO_DEVICE: return "WRITE";
2781 case DMA_FROM_DEVICE: return "READ";
2782 case DMA_NONE: return "NONE";
2783 }
2784
2785 return "(?)";
2786 }
2787
2788 static const char *cmd_state_name(enum transport_state_table t)
2789 {
2790 switch (t) {
2791 case TRANSPORT_NO_STATE: return "NO_STATE";
2792 case TRANSPORT_NEW_CMD: return "NEW_CMD";
2793 case TRANSPORT_WRITE_PENDING: return "WRITE_PENDING";
2794 case TRANSPORT_PROCESSING: return "PROCESSING";
2795 case TRANSPORT_COMPLETE: return "COMPLETE";
2796 case TRANSPORT_ISTATE_PROCESSING:
2797 return "ISTATE_PROCESSING";
2798 case TRANSPORT_COMPLETE_QF_WP: return "COMPLETE_QF_WP";
2799 case TRANSPORT_COMPLETE_QF_OK: return "COMPLETE_QF_OK";
2800 case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR";
2801 }
2802
2803 return "(?)";
2804 }
2805
2806 static void target_append_str(char **str, const char *txt)
2807 {
2808 char *prev = *str;
2809
2810 *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
2811 kstrdup(txt, GFP_ATOMIC);
2812 kfree(prev);
2813 }
2814
2815 /*
2816 * Convert a transport state bitmask into a string. The caller is
2817 * responsible for freeing the returned pointer.
2818 */
2819 static char *target_ts_to_str(u32 ts)
2820 {
2821 char *str = NULL;
2822
2823 if (ts & CMD_T_ABORTED)
2824 target_append_str(&str, "aborted");
2825 if (ts & CMD_T_ACTIVE)
2826 target_append_str(&str, "active");
2827 if (ts & CMD_T_COMPLETE)
2828 target_append_str(&str, "complete");
2829 if (ts & CMD_T_SENT)
2830 target_append_str(&str, "sent");
2831 if (ts & CMD_T_STOP)
2832 target_append_str(&str, "stop");
2833 if (ts & CMD_T_FABRIC_STOP)
2834 target_append_str(&str, "fabric_stop");
2835
2836 return str;
2837 }
2838
2839 static const char *target_tmf_name(enum tcm_tmreq_table tmf)
2840 {
2841 switch (tmf) {
2842 case TMR_ABORT_TASK: return "ABORT_TASK";
2843 case TMR_ABORT_TASK_SET: return "ABORT_TASK_SET";
2844 case TMR_CLEAR_ACA: return "CLEAR_ACA";
2845 case TMR_CLEAR_TASK_SET: return "CLEAR_TASK_SET";
2846 case TMR_LUN_RESET: return "LUN_RESET";
2847 case TMR_TARGET_WARM_RESET: return "TARGET_WARM_RESET";
2848 case TMR_TARGET_COLD_RESET: return "TARGET_COLD_RESET";
2849 case TMR_UNKNOWN: break;
2850 }
2851 return "(?)";
2852 }
2853
2854 void target_show_cmd(const char *pfx, struct se_cmd *cmd)
2855 {
2856 char *ts_str = target_ts_to_str(cmd->transport_state);
2857 const u8 *cdb = cmd->t_task_cdb;
2858 struct se_tmr_req *tmf = cmd->se_tmr_req;
2859
2860 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2861 pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
2862 pfx, cdb[0], cdb[1], cmd->tag,
2863 data_dir_name(cmd->data_direction),
2864 cmd->se_tfo->get_cmd_state(cmd),
2865 cmd_state_name(cmd->t_state), cmd->data_length,
2866 kref_read(&cmd->cmd_kref), ts_str);
2867 } else {
2868 pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
2869 pfx, target_tmf_name(tmf->function), cmd->tag,
2870 tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
2871 cmd_state_name(cmd->t_state),
2872 kref_read(&cmd->cmd_kref), ts_str);
2873 }
2874 kfree(ts_str);
2875 }
2876 EXPORT_SYMBOL(target_show_cmd);
2877
2878 /**
2879 * target_sess_cmd_list_set_waiting - Set sess_tearing_down so no new commands are queued.
2880 * @se_sess: session to flag
2881 */
2882 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2883 {
2884 unsigned long flags;
2885
2886 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2887 se_sess->sess_tearing_down = 1;
2888 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2889 }
2890 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2891
2892 /**
2893 * target_wait_for_sess_cmds - Wait for outstanding commands
2894 * @se_sess: session to wait for active I/O
2895 */
2896 void target_wait_for_sess_cmds(struct se_session *se_sess)
2897 {
2898 struct se_cmd *cmd;
2899 int ret;
2900
2901 WARN_ON_ONCE(!se_sess->sess_tearing_down);
2902
2903 spin_lock_irq(&se_sess->sess_cmd_lock);
2904 do {
2905 ret = wait_event_lock_irq_timeout(
2906 se_sess->cmd_list_wq,
2907 list_empty(&se_sess->sess_cmd_list),
2908 se_sess->sess_cmd_lock, 180 * HZ);
2909 list_for_each_entry(cmd, &se_sess->sess_cmd_list, se_cmd_list)
2910 target_show_cmd("session shutdown: still waiting for ",
2911 cmd);
2912 } while (ret <= 0);
2913 spin_unlock_irq(&se_sess->sess_cmd_lock);
2914 }
2915 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2916
2917 static void target_lun_confirm(struct percpu_ref *ref)
2918 {
2919 struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
2920
2921 complete(&lun->lun_ref_comp);
2922 }
2923
2924 void transport_clear_lun_ref(struct se_lun *lun)
2925 {
2926 /*
2927 * Mark the percpu-ref as DEAD, switch to atomic_t mode, drop
2928 * the initial reference and schedule confirm kill to be
2929 * executed after one full RCU grace period has completed.
2930 */
2931 percpu_ref_kill_and_confirm(&lun->lun_ref, target_lun_confirm);
2932 /*
2933 * The first completion waits for percpu_ref_switch_to_atomic_rcu()
2934 * to call target_lun_confirm after lun->lun_ref has been marked
2935 * as __PERCPU_REF_DEAD on all CPUs, and switches to atomic_t
2936 * mode so that percpu_ref_tryget_live() lookup of lun->lun_ref
2937 * fails for all new incoming I/O.
2938 */
2939 wait_for_completion(&lun->lun_ref_comp);
2940 /*
2941 * The second completion waits for percpu_ref_put_many() to
2942 * invoke ->release() after lun->lun_ref has switched to
2943 * atomic_t mode, and lun->lun_ref.count has reached zero.
2944 *
2945 * At this point all target-core lun->lun_ref references have
2946 * been dropped via transport_lun_remove_cmd(), and it's safe
2947 * to proceed with the remaining LUN shutdown.
2948 */
2949 wait_for_completion(&lun->lun_shutdown_comp);
2950 }
2951
2952 static bool
2953 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2954 bool *aborted, bool *tas, unsigned long *flags)
2955 __releases(&cmd->t_state_lock)
2956 __acquires(&cmd->t_state_lock)
2957 {
2958
2959 assert_spin_locked(&cmd->t_state_lock);
2960 WARN_ON_ONCE(!irqs_disabled());
2961
2962 if (fabric_stop)
2963 cmd->transport_state |= CMD_T_FABRIC_STOP;
2964
2965 if (cmd->transport_state & CMD_T_ABORTED)
2966 *aborted = true;
2967
2968 if (cmd->transport_state & CMD_T_TAS)
2969 *tas = true;
2970
2971 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2972 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2973 return false;
2974
2975 if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2976 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2977 return false;
2978
2979 if (!(cmd->transport_state & CMD_T_ACTIVE))
2980 return false;
2981
2982 if (fabric_stop && *aborted)
2983 return false;
2984
2985 cmd->transport_state |= CMD_T_STOP;
2986
2987 target_show_cmd("wait_for_tasks: Stopping ", cmd);
2988
2989 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2990
2991 while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
2992 180 * HZ))
2993 target_show_cmd("wait for tasks: ", cmd);
2994
2995 spin_lock_irqsave(&cmd->t_state_lock, *flags);
2996 cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2997
2998 pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
2999 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
3000
3001 return true;
3002 }
3003
3004 /**
3005 * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
3006 * @cmd: command to wait on
3007 */
3008 bool transport_wait_for_tasks(struct se_cmd *cmd)
3009 {
3010 unsigned long flags;
3011 bool ret, aborted = false, tas = false;
3012
3013 spin_lock_irqsave(&cmd->t_state_lock, flags);
3014 ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
3015 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3016
3017 return ret;
3018 }
3019 EXPORT_SYMBOL(transport_wait_for_tasks);
3020
3021 struct sense_info {
3022 u8 key;
3023 u8 asc;
3024 u8 ascq;
3025 bool add_sector_info;
3026 };
3027
3028 static const struct sense_info sense_info_table[] = {
3029 [TCM_NO_SENSE] = {
3030 .key = NOT_READY
3031 },
3032 [TCM_NON_EXISTENT_LUN] = {
3033 .key = ILLEGAL_REQUEST,
3034 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
3035 },
3036 [TCM_UNSUPPORTED_SCSI_OPCODE] = {
3037 .key = ILLEGAL_REQUEST,
3038 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3039 },
3040 [TCM_SECTOR_COUNT_TOO_MANY] = {
3041 .key = ILLEGAL_REQUEST,
3042 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3043 },
3044 [TCM_UNKNOWN_MODE_PAGE] = {
3045 .key = ILLEGAL_REQUEST,
3046 .asc = 0x24, /* INVALID FIELD IN CDB */
3047 },
3048 [TCM_CHECK_CONDITION_ABORT_CMD] = {
3049 .key = ABORTED_COMMAND,
3050 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3051 .ascq = 0x03,
3052 },
3053 [TCM_INCORRECT_AMOUNT_OF_DATA] = {
3054 .key = ABORTED_COMMAND,
3055 .asc = 0x0c, /* WRITE ERROR */
3056 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3057 },
3058 [TCM_INVALID_CDB_FIELD] = {
3059 .key = ILLEGAL_REQUEST,
3060 .asc = 0x24, /* INVALID FIELD IN CDB */
3061 },
3062 [TCM_INVALID_PARAMETER_LIST] = {
3063 .key = ILLEGAL_REQUEST,
3064 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3065 },
3066 [TCM_TOO_MANY_TARGET_DESCS] = {
3067 .key = ILLEGAL_REQUEST,
3068 .asc = 0x26,
3069 .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3070 },
3071 [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3072 .key = ILLEGAL_REQUEST,
3073 .asc = 0x26,
3074 .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3075 },
3076 [TCM_TOO_MANY_SEGMENT_DESCS] = {
3077 .key = ILLEGAL_REQUEST,
3078 .asc = 0x26,
3079 .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3080 },
3081 [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3082 .key = ILLEGAL_REQUEST,
3083 .asc = 0x26,
3084 .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3085 },
3086 [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3087 .key = ILLEGAL_REQUEST,
3088 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3089 },
3090 [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3091 .key = ILLEGAL_REQUEST,
3092 .asc = 0x0c, /* WRITE ERROR */
3093 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3094 },
3095 [TCM_SERVICE_CRC_ERROR] = {
3096 .key = ABORTED_COMMAND,
3097 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3098 .ascq = 0x05, /* N/A */
3099 },
3100 [TCM_SNACK_REJECTED] = {
3101 .key = ABORTED_COMMAND,
3102 .asc = 0x11, /* READ ERROR */
3103 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3104 },
3105 [TCM_WRITE_PROTECTED] = {
3106 .key = DATA_PROTECT,
3107 .asc = 0x27, /* WRITE PROTECTED */
3108 },
3109 [TCM_ADDRESS_OUT_OF_RANGE] = {
3110 .key = ILLEGAL_REQUEST,
3111 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3112 },
3113 [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3114 .key = UNIT_ATTENTION,
3115 },
3116 [TCM_CHECK_CONDITION_NOT_READY] = {
3117 .key = NOT_READY,
3118 },
3119 [TCM_MISCOMPARE_VERIFY] = {
3120 .key = MISCOMPARE,
3121 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3122 .ascq = 0x00,
3123 },
3124 [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
3125 .key = ABORTED_COMMAND,
3126 .asc = 0x10,
3127 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
3128 .add_sector_info = true,
3129 },
3130 [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
3131 .key = ABORTED_COMMAND,
3132 .asc = 0x10,
3133 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
3134 .add_sector_info = true,
3135 },
3136 [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
3137 .key = ABORTED_COMMAND,
3138 .asc = 0x10,
3139 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
3140 .add_sector_info = true,
3141 },
3142 [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
3143 .key = COPY_ABORTED,
3144 .asc = 0x0d,
3145 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
3146
3147 },
3148 [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
3149 /*
3150 * Returning ILLEGAL REQUEST would cause immediate IO errors on
3151 * Solaris initiators. Returning NOT READY instead means the
3152 * operations will be retried a finite number of times and we
3153 * can survive intermittent errors.
3154 */
3155 .key = NOT_READY,
3156 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
3157 },
3158 [TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
3159 /*
3160 * From spc4r22 section5.7.7,5.7.8
3161 * If a PERSISTENT RESERVE OUT command with a REGISTER service action
3162 * or a REGISTER AND IGNORE EXISTING KEY service action or
3163 * REGISTER AND MOVE service actionis attempted,
3164 * but there are insufficient device server resources to complete the
3165 * operation, then the command shall be terminated with CHECK CONDITION
3166 * status, with the sense key set to ILLEGAL REQUEST,and the additonal
3167 * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
3168 */
3169 .key = ILLEGAL_REQUEST,
3170 .asc = 0x55,
3171 .ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
3172 },
3173 };
3174
3175 /**
3176 * translate_sense_reason - translate a sense reason into T10 key, asc and ascq
3177 * @cmd: SCSI command in which the resulting sense buffer or SCSI status will
3178 * be stored.
3179 * @reason: LIO sense reason code. If this argument has the value
3180 * TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If
3181 * dequeuing a unit attention fails due to multiple commands being processed
3182 * concurrently, set the command status to BUSY.
3183 *
3184 * Return: 0 upon success or -EINVAL if the sense buffer is too small.
3185 */
3186 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
3187 {
3188 const struct sense_info *si;
3189 u8 *buffer = cmd->sense_buffer;
3190 int r = (__force int)reason;
3191 u8 key, asc, ascq;
3192 bool desc_format = target_sense_desc_format(cmd->se_dev);
3193
3194 if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
3195 si = &sense_info_table[r];
3196 else
3197 si = &sense_info_table[(__force int)
3198 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3199
3200 key = si->key;
3201 if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
3202 if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc,
3203 &ascq)) {
3204 cmd->scsi_status = SAM_STAT_BUSY;
3205 return;
3206 }
3207 } else if (si->asc == 0) {
3208 WARN_ON_ONCE(cmd->scsi_asc == 0);
3209 asc = cmd->scsi_asc;
3210 ascq = cmd->scsi_ascq;
3211 } else {
3212 asc = si->asc;
3213 ascq = si->ascq;
3214 }
3215
3216 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
3217 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
3218 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
3219 scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
3220 if (si->add_sector_info)
3221 WARN_ON_ONCE(scsi_set_sense_information(buffer,
3222 cmd->scsi_sense_length,
3223 cmd->bad_sector) < 0);
3224 }
3225
3226 int
3227 transport_send_check_condition_and_sense(struct se_cmd *cmd,
3228 sense_reason_t reason, int from_transport)
3229 {
3230 unsigned long flags;
3231
3232 spin_lock_irqsave(&cmd->t_state_lock, flags);
3233 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
3234 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3235 return 0;
3236 }
3237 cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
3238 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3239
3240 if (!from_transport)
3241 translate_sense_reason(cmd, reason);
3242
3243 trace_target_cmd_complete(cmd);
3244 return cmd->se_tfo->queue_status(cmd);
3245 }
3246 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
3247
3248 static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
3249 __releases(&cmd->t_state_lock)
3250 __acquires(&cmd->t_state_lock)
3251 {
3252 int ret;
3253
3254 assert_spin_locked(&cmd->t_state_lock);
3255 WARN_ON_ONCE(!irqs_disabled());
3256
3257 if (!(cmd->transport_state & CMD_T_ABORTED))
3258 return 0;
3259 /*
3260 * If cmd has been aborted but either no status is to be sent or it has
3261 * already been sent, just return
3262 */
3263 if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
3264 if (send_status)
3265 cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3266 return 1;
3267 }
3268
3269 pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
3270 " 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);
3271
3272 cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
3273 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3274 trace_target_cmd_complete(cmd);
3275
3276 spin_unlock_irq(&cmd->t_state_lock);
3277 ret = cmd->se_tfo->queue_status(cmd);
3278 if (ret)
3279 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
3280 spin_lock_irq(&cmd->t_state_lock);
3281
3282 return 1;
3283 }
3284
3285 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
3286 {
3287 int ret;
3288
3289 spin_lock_irq(&cmd->t_state_lock);
3290 ret = __transport_check_aborted_status(cmd, send_status);
3291 spin_unlock_irq(&cmd->t_state_lock);
3292
3293 return ret;
3294 }
3295 EXPORT_SYMBOL(transport_check_aborted_status);
3296
3297 void transport_send_task_abort(struct se_cmd *cmd)
3298 {
3299 unsigned long flags;
3300 int ret;
3301
3302 spin_lock_irqsave(&cmd->t_state_lock, flags);
3303 if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
3304 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3305 return;
3306 }
3307 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3308
3309 /*
3310 * If there are still expected incoming fabric WRITEs, we wait
3311 * until until they have completed before sending a TASK_ABORTED
3312 * response. This response with TASK_ABORTED status will be
3313 * queued back to fabric module by transport_check_aborted_status().
3314 */
3315 if (cmd->data_direction == DMA_TO_DEVICE) {
3316 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
3317 spin_lock_irqsave(&cmd->t_state_lock, flags);
3318 if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) {
3319 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3320 goto send_abort;
3321 }
3322 cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3323 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3324 return;
3325 }
3326 }
3327 send_abort:
3328 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3329
3330 transport_lun_remove_cmd(cmd);
3331
3332 pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
3333 cmd->t_task_cdb[0], cmd->tag);
3334
3335 trace_target_cmd_complete(cmd);
3336 ret = cmd->se_tfo->queue_status(cmd);
3337 if (ret)
3338 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
3339 }
3340
3341 static void target_tmr_work(struct work_struct *work)
3342 {
3343 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3344 struct se_device *dev = cmd->se_dev;
3345 struct se_tmr_req *tmr = cmd->se_tmr_req;
3346 unsigned long flags;
3347 int ret;
3348
3349 spin_lock_irqsave(&cmd->t_state_lock, flags);
3350 if (cmd->transport_state & CMD_T_ABORTED) {
3351 tmr->response = TMR_FUNCTION_REJECTED;
3352 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3353 goto check_stop;
3354 }
3355 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3356
3357 switch (tmr->function) {
3358 case TMR_ABORT_TASK:
3359 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3360 break;
3361 case TMR_ABORT_TASK_SET:
3362 case TMR_CLEAR_ACA:
3363 case TMR_CLEAR_TASK_SET:
3364 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3365 break;
3366 case TMR_LUN_RESET:
3367 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3368 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3369 TMR_FUNCTION_REJECTED;
3370 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3371 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3372 cmd->orig_fe_lun, 0x29,
3373 ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3374 }
3375 break;
3376 case TMR_TARGET_WARM_RESET:
3377 tmr->response = TMR_FUNCTION_REJECTED;
3378 break;
3379 case TMR_TARGET_COLD_RESET:
3380 tmr->response = TMR_FUNCTION_REJECTED;
3381 break;
3382 default:
3383 pr_err("Unknown TMR function: 0x%02x.\n",
3384 tmr->function);
3385 tmr->response = TMR_FUNCTION_REJECTED;
3386 break;
3387 }
3388
3389 spin_lock_irqsave(&cmd->t_state_lock, flags);
3390 if (cmd->transport_state & CMD_T_ABORTED) {
3391 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3392 goto check_stop;
3393 }
3394 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3395
3396 cmd->se_tfo->queue_tm_rsp(cmd);
3397
3398 check_stop:
3399 transport_lun_remove_cmd(cmd);
3400 transport_cmd_check_stop_to_fabric(cmd);
3401 }
3402
3403 int transport_generic_handle_tmr(
3404 struct se_cmd *cmd)
3405 {
3406 unsigned long flags;
3407 bool aborted = false;
3408
3409 spin_lock_irqsave(&cmd->t_state_lock, flags);
3410 if (cmd->transport_state & CMD_T_ABORTED) {
3411 aborted = true;
3412 } else {
3413 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3414 cmd->transport_state |= CMD_T_ACTIVE;
3415 }
3416 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3417
3418 if (aborted) {
3419 pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d"
3420 "ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function,
3421 cmd->se_tmr_req->ref_task_tag, cmd->tag);
3422 transport_lun_remove_cmd(cmd);
3423 transport_cmd_check_stop_to_fabric(cmd);
3424 return 0;
3425 }
3426
3427 INIT_WORK(&cmd->work, target_tmr_work);
3428 queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3429 return 0;
3430 }
3431 EXPORT_SYMBOL(transport_generic_handle_tmr);
3432
3433 bool
3434 target_check_wce(struct se_device *dev)
3435 {
3436 bool wce = false;
3437
3438 if (dev->transport->get_write_cache)
3439 wce = dev->transport->get_write_cache(dev);
3440 else if (dev->dev_attrib.emulate_write_cache > 0)
3441 wce = true;
3442
3443 return wce;
3444 }
3445
3446 bool
3447 target_check_fua(struct se_device *dev)
3448 {
3449 return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3450 }
Linux with added FPC-III support