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Merge tag 'for-linus-20190706' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / drivers / target / target_core_transport.c
blob7f06a62f8661db22c1cd61010fc5d74e94de9f59
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3 * Filename: target_core_transport.c
4 *
5 * This file contains the Generic Target Engine Core.
6 *
7 * (c) Copyright 2002-2013 Datera, Inc.
8 *
9 * Nicholas A. Bellinger <nab@kernel.org>
10 *
11 ******************************************************************************/
12
13 #include <linux/net.h>
14 #include <linux/delay.h>
15 #include <linux/string.h>
16 #include <linux/timer.h>
17 #include <linux/slab.h>
18 #include <linux/spinlock.h>
19 #include <linux/kthread.h>
20 #include <linux/in.h>
21 #include <linux/cdrom.h>
22 #include <linux/module.h>
23 #include <linux/ratelimit.h>
24 #include <linux/vmalloc.h>
25 #include <asm/unaligned.h>
26 #include <net/sock.h>
27 #include <net/tcp.h>
28 #include <scsi/scsi_proto.h>
29 #include <scsi/scsi_common.h>
30
31 #include <target/target_core_base.h>
32 #include <target/target_core_backend.h>
33 #include <target/target_core_fabric.h>
34
35 #include "target_core_internal.h"
36 #include "target_core_alua.h"
37 #include "target_core_pr.h"
38 #include "target_core_ua.h"
39
40 #define CREATE_TRACE_POINTS
41 #include <trace/events/target.h>
42
43 static struct workqueue_struct *target_completion_wq;
44 static struct kmem_cache *se_sess_cache;
45 struct kmem_cache *se_ua_cache;
46 struct kmem_cache *t10_pr_reg_cache;
47 struct kmem_cache *t10_alua_lu_gp_cache;
48 struct kmem_cache *t10_alua_lu_gp_mem_cache;
49 struct kmem_cache *t10_alua_tg_pt_gp_cache;
50 struct kmem_cache *t10_alua_lba_map_cache;
51 struct kmem_cache *t10_alua_lba_map_mem_cache;
52
53 static void transport_complete_task_attr(struct se_cmd *cmd);
54 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason);
55 static void transport_handle_queue_full(struct se_cmd *cmd,
56 struct se_device *dev, int err, bool write_pending);
57 static void target_complete_ok_work(struct work_struct *work);
58
59 int init_se_kmem_caches(void)
60 {
61 se_sess_cache = kmem_cache_create("se_sess_cache",
62 sizeof(struct se_session), __alignof__(struct se_session),
63 0, NULL);
64 if (!se_sess_cache) {
65 pr_err("kmem_cache_create() for struct se_session"
66 " failed\n");
67 goto out;
68 }
69 se_ua_cache = kmem_cache_create("se_ua_cache",
70 sizeof(struct se_ua), __alignof__(struct se_ua),
71 0, NULL);
72 if (!se_ua_cache) {
73 pr_err("kmem_cache_create() for struct se_ua failed\n");
74 goto out_free_sess_cache;
75 }
76 t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
77 sizeof(struct t10_pr_registration),
78 __alignof__(struct t10_pr_registration), 0, NULL);
79 if (!t10_pr_reg_cache) {
80 pr_err("kmem_cache_create() for struct t10_pr_registration"
81 " failed\n");
82 goto out_free_ua_cache;
83 }
84 t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
85 sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
86 0, NULL);
87 if (!t10_alua_lu_gp_cache) {
88 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
89 " failed\n");
90 goto out_free_pr_reg_cache;
91 }
92 t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
93 sizeof(struct t10_alua_lu_gp_member),
94 __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
95 if (!t10_alua_lu_gp_mem_cache) {
96 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
97 "cache failed\n");
98 goto out_free_lu_gp_cache;
99 }
100 t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
101 sizeof(struct t10_alua_tg_pt_gp),
102 __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
103 if (!t10_alua_tg_pt_gp_cache) {
104 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
105 "cache failed\n");
106 goto out_free_lu_gp_mem_cache;
107 }
108 t10_alua_lba_map_cache = kmem_cache_create(
109 "t10_alua_lba_map_cache",
110 sizeof(struct t10_alua_lba_map),
111 __alignof__(struct t10_alua_lba_map), 0, NULL);
112 if (!t10_alua_lba_map_cache) {
113 pr_err("kmem_cache_create() for t10_alua_lba_map_"
114 "cache failed\n");
115 goto out_free_tg_pt_gp_cache;
116 }
117 t10_alua_lba_map_mem_cache = kmem_cache_create(
118 "t10_alua_lba_map_mem_cache",
119 sizeof(struct t10_alua_lba_map_member),
120 __alignof__(struct t10_alua_lba_map_member), 0, NULL);
121 if (!t10_alua_lba_map_mem_cache) {
122 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
123 "cache failed\n");
124 goto out_free_lba_map_cache;
125 }
126
127 target_completion_wq = alloc_workqueue("target_completion",
128 WQ_MEM_RECLAIM, 0);
129 if (!target_completion_wq)
130 goto out_free_lba_map_mem_cache;
131
132 return 0;
133
134 out_free_lba_map_mem_cache:
135 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
136 out_free_lba_map_cache:
137 kmem_cache_destroy(t10_alua_lba_map_cache);
138 out_free_tg_pt_gp_cache:
139 kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
140 out_free_lu_gp_mem_cache:
141 kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
142 out_free_lu_gp_cache:
143 kmem_cache_destroy(t10_alua_lu_gp_cache);
144 out_free_pr_reg_cache:
145 kmem_cache_destroy(t10_pr_reg_cache);
146 out_free_ua_cache:
147 kmem_cache_destroy(se_ua_cache);
148 out_free_sess_cache:
149 kmem_cache_destroy(se_sess_cache);
150 out:
151 return -ENOMEM;
152 }
153
154 void release_se_kmem_caches(void)
155 {
156 destroy_workqueue(target_completion_wq);
157 kmem_cache_destroy(se_sess_cache);
158 kmem_cache_destroy(se_ua_cache);
159 kmem_cache_destroy(t10_pr_reg_cache);
160 kmem_cache_destroy(t10_alua_lu_gp_cache);
161 kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
162 kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
163 kmem_cache_destroy(t10_alua_lba_map_cache);
164 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
165 }
166
167 /* This code ensures unique mib indexes are handed out. */
168 static DEFINE_SPINLOCK(scsi_mib_index_lock);
169 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
170
171 /*
172 * Allocate a new row index for the entry type specified
173 */
174 u32 scsi_get_new_index(scsi_index_t type)
175 {
176 u32 new_index;
177
178 BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
179
180 spin_lock(&scsi_mib_index_lock);
181 new_index = ++scsi_mib_index[type];
182 spin_unlock(&scsi_mib_index_lock);
183
184 return new_index;
185 }
186
187 void transport_subsystem_check_init(void)
188 {
189 int ret;
190 static int sub_api_initialized;
191
192 if (sub_api_initialized)
193 return;
194
195 ret = IS_ENABLED(CONFIG_TCM_IBLOCK) && request_module("target_core_iblock");
196 if (ret != 0)
197 pr_err("Unable to load target_core_iblock\n");
198
199 ret = IS_ENABLED(CONFIG_TCM_FILEIO) && request_module("target_core_file");
200 if (ret != 0)
201 pr_err("Unable to load target_core_file\n");
202
203 ret = IS_ENABLED(CONFIG_TCM_PSCSI) && request_module("target_core_pscsi");
204 if (ret != 0)
205 pr_err("Unable to load target_core_pscsi\n");
206
207 ret = IS_ENABLED(CONFIG_TCM_USER2) && request_module("target_core_user");
208 if (ret != 0)
209 pr_err("Unable to load target_core_user\n");
210
211 sub_api_initialized = 1;
212 }
213
214 static void target_release_sess_cmd_refcnt(struct percpu_ref *ref)
215 {
216 struct se_session *sess = container_of(ref, typeof(*sess), cmd_count);
217
218 wake_up(&sess->cmd_list_wq);
219 }
220
221 /**
222 * transport_init_session - initialize a session object
223 * @se_sess: Session object pointer.
224 *
225 * The caller must have zero-initialized @se_sess before calling this function.
226 */
227 int transport_init_session(struct se_session *se_sess)
228 {
229 INIT_LIST_HEAD(&se_sess->sess_list);
230 INIT_LIST_HEAD(&se_sess->sess_acl_list);
231 INIT_LIST_HEAD(&se_sess->sess_cmd_list);
232 spin_lock_init(&se_sess->sess_cmd_lock);
233 init_waitqueue_head(&se_sess->cmd_list_wq);
234 return percpu_ref_init(&se_sess->cmd_count,
235 target_release_sess_cmd_refcnt, 0, GFP_KERNEL);
236 }
237 EXPORT_SYMBOL(transport_init_session);
238
239 /**
240 * transport_alloc_session - allocate a session object and initialize it
241 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
242 */
243 struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
244 {
245 struct se_session *se_sess;
246 int ret;
247
248 se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
249 if (!se_sess) {
250 pr_err("Unable to allocate struct se_session from"
251 " se_sess_cache\n");
252 return ERR_PTR(-ENOMEM);
253 }
254 ret = transport_init_session(se_sess);
255 if (ret < 0) {
256 kmem_cache_free(se_sess_cache, se_sess);
257 return ERR_PTR(ret);
258 }
259 se_sess->sup_prot_ops = sup_prot_ops;
260
261 return se_sess;
262 }
263 EXPORT_SYMBOL(transport_alloc_session);
264
265 /**
266 * transport_alloc_session_tags - allocate target driver private data
267 * @se_sess: Session pointer.
268 * @tag_num: Maximum number of in-flight commands between initiator and target.
269 * @tag_size: Size in bytes of the private data a target driver associates with
270 * each command.
271 */
272 int transport_alloc_session_tags(struct se_session *se_sess,
273 unsigned int tag_num, unsigned int tag_size)
274 {
275 int rc;
276
277 se_sess->sess_cmd_map = kvcalloc(tag_size, tag_num,
278 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
279 if (!se_sess->sess_cmd_map) {
280 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
281 return -ENOMEM;
282 }
283
284 rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
285 false, GFP_KERNEL, NUMA_NO_NODE);
286 if (rc < 0) {
287 pr_err("Unable to init se_sess->sess_tag_pool,"
288 " tag_num: %u\n", tag_num);
289 kvfree(se_sess->sess_cmd_map);
290 se_sess->sess_cmd_map = NULL;
291 return -ENOMEM;
292 }
293
294 return 0;
295 }
296 EXPORT_SYMBOL(transport_alloc_session_tags);
297
298 /**
299 * transport_init_session_tags - allocate a session and target driver private data
300 * @tag_num: Maximum number of in-flight commands between initiator and target.
301 * @tag_size: Size in bytes of the private data a target driver associates with
302 * each command.
303 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
304 */
305 static struct se_session *
306 transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
307 enum target_prot_op sup_prot_ops)
308 {
309 struct se_session *se_sess;
310 int rc;
311
312 if (tag_num != 0 && !tag_size) {
313 pr_err("init_session_tags called with percpu-ida tag_num:"
314 " %u, but zero tag_size\n", tag_num);
315 return ERR_PTR(-EINVAL);
316 }
317 if (!tag_num && tag_size) {
318 pr_err("init_session_tags called with percpu-ida tag_size:"
319 " %u, but zero tag_num\n", tag_size);
320 return ERR_PTR(-EINVAL);
321 }
322
323 se_sess = transport_alloc_session(sup_prot_ops);
324 if (IS_ERR(se_sess))
325 return se_sess;
326
327 rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
328 if (rc < 0) {
329 transport_free_session(se_sess);
330 return ERR_PTR(-ENOMEM);
331 }
332
333 return se_sess;
334 }
335
336 /*
337 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
338 */
339 void __transport_register_session(
340 struct se_portal_group *se_tpg,
341 struct se_node_acl *se_nacl,
342 struct se_session *se_sess,
343 void *fabric_sess_ptr)
344 {
345 const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
346 unsigned char buf[PR_REG_ISID_LEN];
347 unsigned long flags;
348
349 se_sess->se_tpg = se_tpg;
350 se_sess->fabric_sess_ptr = fabric_sess_ptr;
351 /*
352 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
353 *
354 * Only set for struct se_session's that will actually be moving I/O.
355 * eg: *NOT* discovery sessions.
356 */
357 if (se_nacl) {
358 /*
359 *
360 * Determine if fabric allows for T10-PI feature bits exposed to
361 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
362 *
363 * If so, then always save prot_type on a per se_node_acl node
364 * basis and re-instate the previous sess_prot_type to avoid
365 * disabling PI from below any previously initiator side
366 * registered LUNs.
367 */
368 if (se_nacl->saved_prot_type)
369 se_sess->sess_prot_type = se_nacl->saved_prot_type;
370 else if (tfo->tpg_check_prot_fabric_only)
371 se_sess->sess_prot_type = se_nacl->saved_prot_type =
372 tfo->tpg_check_prot_fabric_only(se_tpg);
373 /*
374 * If the fabric module supports an ISID based TransportID,
375 * save this value in binary from the fabric I_T Nexus now.
376 */
377 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
378 memset(&buf[0], 0, PR_REG_ISID_LEN);
379 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
380 &buf[0], PR_REG_ISID_LEN);
381 se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
382 }
383
384 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
385 /*
386 * The se_nacl->nacl_sess pointer will be set to the
387 * last active I_T Nexus for each struct se_node_acl.
388 */
389 se_nacl->nacl_sess = se_sess;
390
391 list_add_tail(&se_sess->sess_acl_list,
392 &se_nacl->acl_sess_list);
393 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
394 }
395 list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
396
397 pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
398 se_tpg->se_tpg_tfo->fabric_name, se_sess->fabric_sess_ptr);
399 }
400 EXPORT_SYMBOL(__transport_register_session);
401
402 void transport_register_session(
403 struct se_portal_group *se_tpg,
404 struct se_node_acl *se_nacl,
405 struct se_session *se_sess,
406 void *fabric_sess_ptr)
407 {
408 unsigned long flags;
409
410 spin_lock_irqsave(&se_tpg->session_lock, flags);
411 __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
412 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
413 }
414 EXPORT_SYMBOL(transport_register_session);
415
416 struct se_session *
417 target_setup_session(struct se_portal_group *tpg,
418 unsigned int tag_num, unsigned int tag_size,
419 enum target_prot_op prot_op,
420 const char *initiatorname, void *private,
421 int (*callback)(struct se_portal_group *,
422 struct se_session *, void *))
423 {
424 struct se_session *sess;
425
426 /*
427 * If the fabric driver is using percpu-ida based pre allocation
428 * of I/O descriptor tags, go ahead and perform that setup now..
429 */
430 if (tag_num != 0)
431 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
432 else
433 sess = transport_alloc_session(prot_op);
434
435 if (IS_ERR(sess))
436 return sess;
437
438 sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
439 (unsigned char *)initiatorname);
440 if (!sess->se_node_acl) {
441 transport_free_session(sess);
442 return ERR_PTR(-EACCES);
443 }
444 /*
445 * Go ahead and perform any remaining fabric setup that is
446 * required before transport_register_session().
447 */
448 if (callback != NULL) {
449 int rc = callback(tpg, sess, private);
450 if (rc) {
451 transport_free_session(sess);
452 return ERR_PTR(rc);
453 }
454 }
455
456 transport_register_session(tpg, sess->se_node_acl, sess, private);
457 return sess;
458 }
459 EXPORT_SYMBOL(target_setup_session);
460
461 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
462 {
463 struct se_session *se_sess;
464 ssize_t len = 0;
465
466 spin_lock_bh(&se_tpg->session_lock);
467 list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
468 if (!se_sess->se_node_acl)
469 continue;
470 if (!se_sess->se_node_acl->dynamic_node_acl)
471 continue;
472 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
473 break;
474
475 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
476 se_sess->se_node_acl->initiatorname);
477 len += 1; /* Include NULL terminator */
478 }
479 spin_unlock_bh(&se_tpg->session_lock);
480
481 return len;
482 }
483 EXPORT_SYMBOL(target_show_dynamic_sessions);
484
485 static void target_complete_nacl(struct kref *kref)
486 {
487 struct se_node_acl *nacl = container_of(kref,
488 struct se_node_acl, acl_kref);
489 struct se_portal_group *se_tpg = nacl->se_tpg;
490
491 if (!nacl->dynamic_stop) {
492 complete(&nacl->acl_free_comp);
493 return;
494 }
495
496 mutex_lock(&se_tpg->acl_node_mutex);
497 list_del_init(&nacl->acl_list);
498 mutex_unlock(&se_tpg->acl_node_mutex);
499
500 core_tpg_wait_for_nacl_pr_ref(nacl);
501 core_free_device_list_for_node(nacl, se_tpg);
502 kfree(nacl);
503 }
504
505 void target_put_nacl(struct se_node_acl *nacl)
506 {
507 kref_put(&nacl->acl_kref, target_complete_nacl);
508 }
509 EXPORT_SYMBOL(target_put_nacl);
510
511 void transport_deregister_session_configfs(struct se_session *se_sess)
512 {
513 struct se_node_acl *se_nacl;
514 unsigned long flags;
515 /*
516 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
517 */
518 se_nacl = se_sess->se_node_acl;
519 if (se_nacl) {
520 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
521 if (!list_empty(&se_sess->sess_acl_list))
522 list_del_init(&se_sess->sess_acl_list);
523 /*
524 * If the session list is empty, then clear the pointer.
525 * Otherwise, set the struct se_session pointer from the tail
526 * element of the per struct se_node_acl active session list.
527 */
528 if (list_empty(&se_nacl->acl_sess_list))
529 se_nacl->nacl_sess = NULL;
530 else {
531 se_nacl->nacl_sess = container_of(
532 se_nacl->acl_sess_list.prev,
533 struct se_session, sess_acl_list);
534 }
535 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
536 }
537 }
538 EXPORT_SYMBOL(transport_deregister_session_configfs);
539
540 void transport_free_session(struct se_session *se_sess)
541 {
542 struct se_node_acl *se_nacl = se_sess->se_node_acl;
543
544 /*
545 * Drop the se_node_acl->nacl_kref obtained from within
546 * core_tpg_get_initiator_node_acl().
547 */
548 if (se_nacl) {
549 struct se_portal_group *se_tpg = se_nacl->se_tpg;
550 const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
551 unsigned long flags;
552
553 se_sess->se_node_acl = NULL;
554
555 /*
556 * Also determine if we need to drop the extra ->cmd_kref if
557 * it had been previously dynamically generated, and
558 * the endpoint is not caching dynamic ACLs.
559 */
560 mutex_lock(&se_tpg->acl_node_mutex);
561 if (se_nacl->dynamic_node_acl &&
562 !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
563 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
564 if (list_empty(&se_nacl->acl_sess_list))
565 se_nacl->dynamic_stop = true;
566 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
567
568 if (se_nacl->dynamic_stop)
569 list_del_init(&se_nacl->acl_list);
570 }
571 mutex_unlock(&se_tpg->acl_node_mutex);
572
573 if (se_nacl->dynamic_stop)
574 target_put_nacl(se_nacl);
575
576 target_put_nacl(se_nacl);
577 }
578 if (se_sess->sess_cmd_map) {
579 sbitmap_queue_free(&se_sess->sess_tag_pool);
580 kvfree(se_sess->sess_cmd_map);
581 }
582 percpu_ref_exit(&se_sess->cmd_count);
583 kmem_cache_free(se_sess_cache, se_sess);
584 }
585 EXPORT_SYMBOL(transport_free_session);
586
587 void transport_deregister_session(struct se_session *se_sess)
588 {
589 struct se_portal_group *se_tpg = se_sess->se_tpg;
590 unsigned long flags;
591
592 if (!se_tpg) {
593 transport_free_session(se_sess);
594 return;
595 }
596
597 spin_lock_irqsave(&se_tpg->session_lock, flags);
598 list_del(&se_sess->sess_list);
599 se_sess->se_tpg = NULL;
600 se_sess->fabric_sess_ptr = NULL;
601 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
602
603 pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
604 se_tpg->se_tpg_tfo->fabric_name);
605 /*
606 * If last kref is dropping now for an explicit NodeACL, awake sleeping
607 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
608 * removal context from within transport_free_session() code.
609 *
610 * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
611 * to release all remaining generate_node_acl=1 created ACL resources.
612 */
613
614 transport_free_session(se_sess);
615 }
616 EXPORT_SYMBOL(transport_deregister_session);
617
618 void target_remove_session(struct se_session *se_sess)
619 {
620 transport_deregister_session_configfs(se_sess);
621 transport_deregister_session(se_sess);
622 }
623 EXPORT_SYMBOL(target_remove_session);
624
625 static void target_remove_from_state_list(struct se_cmd *cmd)
626 {
627 struct se_device *dev = cmd->se_dev;
628 unsigned long flags;
629
630 if (!dev)
631 return;
632
633 spin_lock_irqsave(&dev->execute_task_lock, flags);
634 if (cmd->state_active) {
635 list_del(&cmd->state_list);
636 cmd->state_active = false;
637 }
638 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
639 }
640
641 /*
642 * This function is called by the target core after the target core has
643 * finished processing a SCSI command or SCSI TMF. Both the regular command
644 * processing code and the code for aborting commands can call this
645 * function. CMD_T_STOP is set if and only if another thread is waiting
646 * inside transport_wait_for_tasks() for t_transport_stop_comp.
647 */
648 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
649 {
650 unsigned long flags;
651
652 target_remove_from_state_list(cmd);
653
654 spin_lock_irqsave(&cmd->t_state_lock, flags);
655 /*
656 * Determine if frontend context caller is requesting the stopping of
657 * this command for frontend exceptions.
658 */
659 if (cmd->transport_state & CMD_T_STOP) {
660 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
661 __func__, __LINE__, cmd->tag);
662
663 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
664
665 complete_all(&cmd->t_transport_stop_comp);
666 return 1;
667 }
668 cmd->transport_state &= ~CMD_T_ACTIVE;
669 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
670
671 /*
672 * Some fabric modules like tcm_loop can release their internally
673 * allocated I/O reference and struct se_cmd now.
674 *
675 * Fabric modules are expected to return '1' here if the se_cmd being
676 * passed is released at this point, or zero if not being released.
677 */
678 return cmd->se_tfo->check_stop_free(cmd);
679 }
680
681 static void target_complete_failure_work(struct work_struct *work)
682 {
683 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
684
685 transport_generic_request_failure(cmd,
686 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
687 }
688
689 /*
690 * Used when asking transport to copy Sense Data from the underlying
691 * Linux/SCSI struct scsi_cmnd
692 */
693 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
694 {
695 struct se_device *dev = cmd->se_dev;
696
697 WARN_ON(!cmd->se_lun);
698
699 if (!dev)
700 return NULL;
701
702 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
703 return NULL;
704
705 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
706
707 pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
708 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
709 return cmd->sense_buffer;
710 }
711
712 void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
713 {
714 unsigned char *cmd_sense_buf;
715 unsigned long flags;
716
717 spin_lock_irqsave(&cmd->t_state_lock, flags);
718 cmd_sense_buf = transport_get_sense_buffer(cmd);
719 if (!cmd_sense_buf) {
720 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
721 return;
722 }
723
724 cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
725 memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
726 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
727 }
728 EXPORT_SYMBOL(transport_copy_sense_to_cmd);
729
730 static void target_handle_abort(struct se_cmd *cmd)
731 {
732 bool tas = cmd->transport_state & CMD_T_TAS;
733 bool ack_kref = cmd->se_cmd_flags & SCF_ACK_KREF;
734 int ret;
735
736 pr_debug("tag %#llx: send_abort_response = %d\n", cmd->tag, tas);
737
738 if (tas) {
739 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
740 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
741 pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
742 cmd->t_task_cdb[0], cmd->tag);
743 trace_target_cmd_complete(cmd);
744 ret = cmd->se_tfo->queue_status(cmd);
745 if (ret) {
746 transport_handle_queue_full(cmd, cmd->se_dev,
747 ret, false);
748 return;
749 }
750 } else {
751 cmd->se_tmr_req->response = TMR_FUNCTION_REJECTED;
752 cmd->se_tfo->queue_tm_rsp(cmd);
753 }
754 } else {
755 /*
756 * Allow the fabric driver to unmap any resources before
757 * releasing the descriptor via TFO->release_cmd().
758 */
759 cmd->se_tfo->aborted_task(cmd);
760 if (ack_kref)
761 WARN_ON_ONCE(target_put_sess_cmd(cmd) != 0);
762 /*
763 * To do: establish a unit attention condition on the I_T
764 * nexus associated with cmd. See also the paragraph "Aborting
765 * commands" in SAM.
766 */
767 }
768
769 WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0);
770
771 transport_cmd_check_stop_to_fabric(cmd);
772 }
773
774 static void target_abort_work(struct work_struct *work)
775 {
776 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
777
778 target_handle_abort(cmd);
779 }
780
781 static bool target_cmd_interrupted(struct se_cmd *cmd)
782 {
783 int post_ret;
784
785 if (cmd->transport_state & CMD_T_ABORTED) {
786 if (cmd->transport_complete_callback)
787 cmd->transport_complete_callback(cmd, false, &post_ret);
788 INIT_WORK(&cmd->work, target_abort_work);
789 queue_work(target_completion_wq, &cmd->work);
790 return true;
791 } else if (cmd->transport_state & CMD_T_STOP) {
792 if (cmd->transport_complete_callback)
793 cmd->transport_complete_callback(cmd, false, &post_ret);
794 complete_all(&cmd->t_transport_stop_comp);
795 return true;
796 }
797
798 return false;
799 }
800
801 /* May be called from interrupt context so must not sleep. */
802 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
803 {
804 int success;
805 unsigned long flags;
806
807 if (target_cmd_interrupted(cmd))
808 return;
809
810 cmd->scsi_status = scsi_status;
811
812 spin_lock_irqsave(&cmd->t_state_lock, flags);
813 switch (cmd->scsi_status) {
814 case SAM_STAT_CHECK_CONDITION:
815 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
816 success = 1;
817 else
818 success = 0;
819 break;
820 default:
821 success = 1;
822 break;
823 }
824
825 cmd->t_state = TRANSPORT_COMPLETE;
826 cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
827 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
828
829 INIT_WORK(&cmd->work, success ? target_complete_ok_work :
830 target_complete_failure_work);
831 if (cmd->se_cmd_flags & SCF_USE_CPUID)
832 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
833 else
834 queue_work(target_completion_wq, &cmd->work);
835 }
836 EXPORT_SYMBOL(target_complete_cmd);
837
838 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
839 {
840 if ((scsi_status == SAM_STAT_GOOD ||
841 cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
842 length < cmd->data_length) {
843 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
844 cmd->residual_count += cmd->data_length - length;
845 } else {
846 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
847 cmd->residual_count = cmd->data_length - length;
848 }
849
850 cmd->data_length = length;
851 }
852
853 target_complete_cmd(cmd, scsi_status);
854 }
855 EXPORT_SYMBOL(target_complete_cmd_with_length);
856
857 static void target_add_to_state_list(struct se_cmd *cmd)
858 {
859 struct se_device *dev = cmd->se_dev;
860 unsigned long flags;
861
862 spin_lock_irqsave(&dev->execute_task_lock, flags);
863 if (!cmd->state_active) {
864 list_add_tail(&cmd->state_list, &dev->state_list);
865 cmd->state_active = true;
866 }
867 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
868 }
869
870 /*
871 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
872 */
873 static void transport_write_pending_qf(struct se_cmd *cmd);
874 static void transport_complete_qf(struct se_cmd *cmd);
875
876 void target_qf_do_work(struct work_struct *work)
877 {
878 struct se_device *dev = container_of(work, struct se_device,
879 qf_work_queue);
880 LIST_HEAD(qf_cmd_list);
881 struct se_cmd *cmd, *cmd_tmp;
882
883 spin_lock_irq(&dev->qf_cmd_lock);
884 list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
885 spin_unlock_irq(&dev->qf_cmd_lock);
886
887 list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
888 list_del(&cmd->se_qf_node);
889 atomic_dec_mb(&dev->dev_qf_count);
890
891 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
892 " context: %s\n", cmd->se_tfo->fabric_name, cmd,
893 (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
894 (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
895 : "UNKNOWN");
896
897 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
898 transport_write_pending_qf(cmd);
899 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
900 cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
901 transport_complete_qf(cmd);
902 }
903 }
904
905 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
906 {
907 switch (cmd->data_direction) {
908 case DMA_NONE:
909 return "NONE";
910 case DMA_FROM_DEVICE:
911 return "READ";
912 case DMA_TO_DEVICE:
913 return "WRITE";
914 case DMA_BIDIRECTIONAL:
915 return "BIDI";
916 default:
917 break;
918 }
919
920 return "UNKNOWN";
921 }
922
923 void transport_dump_dev_state(
924 struct se_device *dev,
925 char *b,
926 int *bl)
927 {
928 *bl += sprintf(b + *bl, "Status: ");
929 if (dev->export_count)
930 *bl += sprintf(b + *bl, "ACTIVATED");
931 else
932 *bl += sprintf(b + *bl, "DEACTIVATED");
933
934 *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
935 *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
936 dev->dev_attrib.block_size,
937 dev->dev_attrib.hw_max_sectors);
938 *bl += sprintf(b + *bl, " ");
939 }
940
941 void transport_dump_vpd_proto_id(
942 struct t10_vpd *vpd,
943 unsigned char *p_buf,
944 int p_buf_len)
945 {
946 unsigned char buf[VPD_TMP_BUF_SIZE];
947 int len;
948
949 memset(buf, 0, VPD_TMP_BUF_SIZE);
950 len = sprintf(buf, "T10 VPD Protocol Identifier: ");
951
952 switch (vpd->protocol_identifier) {
953 case 0x00:
954 sprintf(buf+len, "Fibre Channel\n");
955 break;
956 case 0x10:
957 sprintf(buf+len, "Parallel SCSI\n");
958 break;
959 case 0x20:
960 sprintf(buf+len, "SSA\n");
961 break;
962 case 0x30:
963 sprintf(buf+len, "IEEE 1394\n");
964 break;
965 case 0x40:
966 sprintf(buf+len, "SCSI Remote Direct Memory Access"
967 " Protocol\n");
968 break;
969 case 0x50:
970 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
971 break;
972 case 0x60:
973 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
974 break;
975 case 0x70:
976 sprintf(buf+len, "Automation/Drive Interface Transport"
977 " Protocol\n");
978 break;
979 case 0x80:
980 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
981 break;
982 default:
983 sprintf(buf+len, "Unknown 0x%02x\n",
984 vpd->protocol_identifier);
985 break;
986 }
987
988 if (p_buf)
989 strncpy(p_buf, buf, p_buf_len);
990 else
991 pr_debug("%s", buf);
992 }
993
994 void
995 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
996 {
997 /*
998 * Check if the Protocol Identifier Valid (PIV) bit is set..
999 *
1000 * from spc3r23.pdf section 7.5.1
1001 */
1002 if (page_83[1] & 0x80) {
1003 vpd->protocol_identifier = (page_83[0] & 0xf0);
1004 vpd->protocol_identifier_set = 1;
1005 transport_dump_vpd_proto_id(vpd, NULL, 0);
1006 }
1007 }
1008 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1009
1010 int transport_dump_vpd_assoc(
1011 struct t10_vpd *vpd,
1012 unsigned char *p_buf,
1013 int p_buf_len)
1014 {
1015 unsigned char buf[VPD_TMP_BUF_SIZE];
1016 int ret = 0;
1017 int len;
1018
1019 memset(buf, 0, VPD_TMP_BUF_SIZE);
1020 len = sprintf(buf, "T10 VPD Identifier Association: ");
1021
1022 switch (vpd->association) {
1023 case 0x00:
1024 sprintf(buf+len, "addressed logical unit\n");
1025 break;
1026 case 0x10:
1027 sprintf(buf+len, "target port\n");
1028 break;
1029 case 0x20:
1030 sprintf(buf+len, "SCSI target device\n");
1031 break;
1032 default:
1033 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1034 ret = -EINVAL;
1035 break;
1036 }
1037
1038 if (p_buf)
1039 strncpy(p_buf, buf, p_buf_len);
1040 else
1041 pr_debug("%s", buf);
1042
1043 return ret;
1044 }
1045
1046 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1047 {
1048 /*
1049 * The VPD identification association..
1050 *
1051 * from spc3r23.pdf Section 7.6.3.1 Table 297
1052 */
1053 vpd->association = (page_83[1] & 0x30);
1054 return transport_dump_vpd_assoc(vpd, NULL, 0);
1055 }
1056 EXPORT_SYMBOL(transport_set_vpd_assoc);
1057
1058 int transport_dump_vpd_ident_type(
1059 struct t10_vpd *vpd,
1060 unsigned char *p_buf,
1061 int p_buf_len)
1062 {
1063 unsigned char buf[VPD_TMP_BUF_SIZE];
1064 int ret = 0;
1065 int len;
1066
1067 memset(buf, 0, VPD_TMP_BUF_SIZE);
1068 len = sprintf(buf, "T10 VPD Identifier Type: ");
1069
1070 switch (vpd->device_identifier_type) {
1071 case 0x00:
1072 sprintf(buf+len, "Vendor specific\n");
1073 break;
1074 case 0x01:
1075 sprintf(buf+len, "T10 Vendor ID based\n");
1076 break;
1077 case 0x02:
1078 sprintf(buf+len, "EUI-64 based\n");
1079 break;
1080 case 0x03:
1081 sprintf(buf+len, "NAA\n");
1082 break;
1083 case 0x04:
1084 sprintf(buf+len, "Relative target port identifier\n");
1085 break;
1086 case 0x08:
1087 sprintf(buf+len, "SCSI name string\n");
1088 break;
1089 default:
1090 sprintf(buf+len, "Unsupported: 0x%02x\n",
1091 vpd->device_identifier_type);
1092 ret = -EINVAL;
1093 break;
1094 }
1095
1096 if (p_buf) {
1097 if (p_buf_len < strlen(buf)+1)
1098 return -EINVAL;
1099 strncpy(p_buf, buf, p_buf_len);
1100 } else {
1101 pr_debug("%s", buf);
1102 }
1103
1104 return ret;
1105 }
1106
1107 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1108 {
1109 /*
1110 * The VPD identifier type..
1111 *
1112 * from spc3r23.pdf Section 7.6.3.1 Table 298
1113 */
1114 vpd->device_identifier_type = (page_83[1] & 0x0f);
1115 return transport_dump_vpd_ident_type(vpd, NULL, 0);
1116 }
1117 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1118
1119 int transport_dump_vpd_ident(
1120 struct t10_vpd *vpd,
1121 unsigned char *p_buf,
1122 int p_buf_len)
1123 {
1124 unsigned char buf[VPD_TMP_BUF_SIZE];
1125 int ret = 0;
1126
1127 memset(buf, 0, VPD_TMP_BUF_SIZE);
1128
1129 switch (vpd->device_identifier_code_set) {
1130 case 0x01: /* Binary */
1131 snprintf(buf, sizeof(buf),
1132 "T10 VPD Binary Device Identifier: %s\n",
1133 &vpd->device_identifier[0]);
1134 break;
1135 case 0x02: /* ASCII */
1136 snprintf(buf, sizeof(buf),
1137 "T10 VPD ASCII Device Identifier: %s\n",
1138 &vpd->device_identifier[0]);
1139 break;
1140 case 0x03: /* UTF-8 */
1141 snprintf(buf, sizeof(buf),
1142 "T10 VPD UTF-8 Device Identifier: %s\n",
1143 &vpd->device_identifier[0]);
1144 break;
1145 default:
1146 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1147 " 0x%02x", vpd->device_identifier_code_set);
1148 ret = -EINVAL;
1149 break;
1150 }
1151
1152 if (p_buf)
1153 strncpy(p_buf, buf, p_buf_len);
1154 else
1155 pr_debug("%s", buf);
1156
1157 return ret;
1158 }
1159
1160 int
1161 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1162 {
1163 static const char hex_str[] = "0123456789abcdef";
1164 int j = 0, i = 4; /* offset to start of the identifier */
1165
1166 /*
1167 * The VPD Code Set (encoding)
1168 *
1169 * from spc3r23.pdf Section 7.6.3.1 Table 296
1170 */
1171 vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1172 switch (vpd->device_identifier_code_set) {
1173 case 0x01: /* Binary */
1174 vpd->device_identifier[j++] =
1175 hex_str[vpd->device_identifier_type];
1176 while (i < (4 + page_83[3])) {
1177 vpd->device_identifier[j++] =
1178 hex_str[(page_83[i] & 0xf0) >> 4];
1179 vpd->device_identifier[j++] =
1180 hex_str[page_83[i] & 0x0f];
1181 i++;
1182 }
1183 break;
1184 case 0x02: /* ASCII */
1185 case 0x03: /* UTF-8 */
1186 while (i < (4 + page_83[3]))
1187 vpd->device_identifier[j++] = page_83[i++];
1188 break;
1189 default:
1190 break;
1191 }
1192
1193 return transport_dump_vpd_ident(vpd, NULL, 0);
1194 }
1195 EXPORT_SYMBOL(transport_set_vpd_ident);
1196
1197 static sense_reason_t
1198 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1199 unsigned int size)
1200 {
1201 u32 mtl;
1202
1203 if (!cmd->se_tfo->max_data_sg_nents)
1204 return TCM_NO_SENSE;
1205 /*
1206 * Check if fabric enforced maximum SGL entries per I/O descriptor
1207 * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT +
1208 * residual_count and reduce original cmd->data_length to maximum
1209 * length based on single PAGE_SIZE entry scatter-lists.
1210 */
1211 mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1212 if (cmd->data_length > mtl) {
1213 /*
1214 * If an existing CDB overflow is present, calculate new residual
1215 * based on CDB size minus fabric maximum transfer length.
1216 *
1217 * If an existing CDB underflow is present, calculate new residual
1218 * based on original cmd->data_length minus fabric maximum transfer
1219 * length.
1220 *
1221 * Otherwise, set the underflow residual based on cmd->data_length
1222 * minus fabric maximum transfer length.
1223 */
1224 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1225 cmd->residual_count = (size - mtl);
1226 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1227 u32 orig_dl = size + cmd->residual_count;
1228 cmd->residual_count = (orig_dl - mtl);
1229 } else {
1230 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1231 cmd->residual_count = (cmd->data_length - mtl);
1232 }
1233 cmd->data_length = mtl;
1234 /*
1235 * Reset sbc_check_prot() calculated protection payload
1236 * length based upon the new smaller MTL.
1237 */
1238 if (cmd->prot_length) {
1239 u32 sectors = (mtl / dev->dev_attrib.block_size);
1240 cmd->prot_length = dev->prot_length * sectors;
1241 }
1242 }
1243 return TCM_NO_SENSE;
1244 }
1245
1246 sense_reason_t
1247 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1248 {
1249 struct se_device *dev = cmd->se_dev;
1250
1251 if (cmd->unknown_data_length) {
1252 cmd->data_length = size;
1253 } else if (size != cmd->data_length) {
1254 pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1255 " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1256 " 0x%02x\n", cmd->se_tfo->fabric_name,
1257 cmd->data_length, size, cmd->t_task_cdb[0]);
1258
1259 if (cmd->data_direction == DMA_TO_DEVICE) {
1260 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1261 pr_err_ratelimited("Rejecting underflow/overflow"
1262 " for WRITE data CDB\n");
1263 return TCM_INVALID_CDB_FIELD;
1264 }
1265 /*
1266 * Some fabric drivers like iscsi-target still expect to
1267 * always reject overflow writes. Reject this case until
1268 * full fabric driver level support for overflow writes
1269 * is introduced tree-wide.
1270 */
1271 if (size > cmd->data_length) {
1272 pr_err_ratelimited("Rejecting overflow for"
1273 " WRITE control CDB\n");
1274 return TCM_INVALID_CDB_FIELD;
1275 }
1276 }
1277 /*
1278 * Reject READ_* or WRITE_* with overflow/underflow for
1279 * type SCF_SCSI_DATA_CDB.
1280 */
1281 if (dev->dev_attrib.block_size != 512) {
1282 pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1283 " CDB on non 512-byte sector setup subsystem"
1284 " plugin: %s\n", dev->transport->name);
1285 /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1286 return TCM_INVALID_CDB_FIELD;
1287 }
1288 /*
1289 * For the overflow case keep the existing fabric provided
1290 * ->data_length. Otherwise for the underflow case, reset
1291 * ->data_length to the smaller SCSI expected data transfer
1292 * length.
1293 */
1294 if (size > cmd->data_length) {
1295 cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1296 cmd->residual_count = (size - cmd->data_length);
1297 } else {
1298 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1299 cmd->residual_count = (cmd->data_length - size);
1300 cmd->data_length = size;
1301 }
1302 }
1303
1304 return target_check_max_data_sg_nents(cmd, dev, size);
1305
1306 }
1307
1308 /*
1309 * Used by fabric modules containing a local struct se_cmd within their
1310 * fabric dependent per I/O descriptor.
1311 *
1312 * Preserves the value of @cmd->tag.
1313 */
1314 void transport_init_se_cmd(
1315 struct se_cmd *cmd,
1316 const struct target_core_fabric_ops *tfo,
1317 struct se_session *se_sess,
1318 u32 data_length,
1319 int data_direction,
1320 int task_attr,
1321 unsigned char *sense_buffer)
1322 {
1323 INIT_LIST_HEAD(&cmd->se_delayed_node);
1324 INIT_LIST_HEAD(&cmd->se_qf_node);
1325 INIT_LIST_HEAD(&cmd->se_cmd_list);
1326 INIT_LIST_HEAD(&cmd->state_list);
1327 init_completion(&cmd->t_transport_stop_comp);
1328 cmd->free_compl = NULL;
1329 cmd->abrt_compl = NULL;
1330 spin_lock_init(&cmd->t_state_lock);
1331 INIT_WORK(&cmd->work, NULL);
1332 kref_init(&cmd->cmd_kref);
1333
1334 cmd->se_tfo = tfo;
1335 cmd->se_sess = se_sess;
1336 cmd->data_length = data_length;
1337 cmd->data_direction = data_direction;
1338 cmd->sam_task_attr = task_attr;
1339 cmd->sense_buffer = sense_buffer;
1340
1341 cmd->state_active = false;
1342 }
1343 EXPORT_SYMBOL(transport_init_se_cmd);
1344
1345 static sense_reason_t
1346 transport_check_alloc_task_attr(struct se_cmd *cmd)
1347 {
1348 struct se_device *dev = cmd->se_dev;
1349
1350 /*
1351 * Check if SAM Task Attribute emulation is enabled for this
1352 * struct se_device storage object
1353 */
1354 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1355 return 0;
1356
1357 if (cmd->sam_task_attr == TCM_ACA_TAG) {
1358 pr_debug("SAM Task Attribute ACA"
1359 " emulation is not supported\n");
1360 return TCM_INVALID_CDB_FIELD;
1361 }
1362
1363 return 0;
1364 }
1365
1366 sense_reason_t
1367 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1368 {
1369 struct se_device *dev = cmd->se_dev;
1370 sense_reason_t ret;
1371
1372 /*
1373 * Ensure that the received CDB is less than the max (252 + 8) bytes
1374 * for VARIABLE_LENGTH_CMD
1375 */
1376 if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1377 pr_err("Received SCSI CDB with command_size: %d that"
1378 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1379 scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1380 return TCM_INVALID_CDB_FIELD;
1381 }
1382 /*
1383 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1384 * allocate the additional extended CDB buffer now.. Otherwise
1385 * setup the pointer from __t_task_cdb to t_task_cdb.
1386 */
1387 if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1388 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1389 GFP_KERNEL);
1390 if (!cmd->t_task_cdb) {
1391 pr_err("Unable to allocate cmd->t_task_cdb"
1392 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1393 scsi_command_size(cdb),
1394 (unsigned long)sizeof(cmd->__t_task_cdb));
1395 return TCM_OUT_OF_RESOURCES;
1396 }
1397 } else
1398 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1399 /*
1400 * Copy the original CDB into cmd->
1401 */
1402 memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1403
1404 trace_target_sequencer_start(cmd);
1405
1406 ret = dev->transport->parse_cdb(cmd);
1407 if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1408 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1409 cmd->se_tfo->fabric_name,
1410 cmd->se_sess->se_node_acl->initiatorname,
1411 cmd->t_task_cdb[0]);
1412 if (ret)
1413 return ret;
1414
1415 ret = transport_check_alloc_task_attr(cmd);
1416 if (ret)
1417 return ret;
1418
1419 cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1420 atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1421 return 0;
1422 }
1423 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1424
1425 /*
1426 * Used by fabric module frontends to queue tasks directly.
1427 * May only be used from process context.
1428 */
1429 int transport_handle_cdb_direct(
1430 struct se_cmd *cmd)
1431 {
1432 sense_reason_t ret;
1433
1434 if (!cmd->se_lun) {
1435 dump_stack();
1436 pr_err("cmd->se_lun is NULL\n");
1437 return -EINVAL;
1438 }
1439 if (in_interrupt()) {
1440 dump_stack();
1441 pr_err("transport_generic_handle_cdb cannot be called"
1442 " from interrupt context\n");
1443 return -EINVAL;
1444 }
1445 /*
1446 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1447 * outstanding descriptors are handled correctly during shutdown via
1448 * transport_wait_for_tasks()
1449 *
1450 * Also, we don't take cmd->t_state_lock here as we only expect
1451 * this to be called for initial descriptor submission.
1452 */
1453 cmd->t_state = TRANSPORT_NEW_CMD;
1454 cmd->transport_state |= CMD_T_ACTIVE;
1455
1456 /*
1457 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1458 * so follow TRANSPORT_NEW_CMD processing thread context usage
1459 * and call transport_generic_request_failure() if necessary..
1460 */
1461 ret = transport_generic_new_cmd(cmd);
1462 if (ret)
1463 transport_generic_request_failure(cmd, ret);
1464 return 0;
1465 }
1466 EXPORT_SYMBOL(transport_handle_cdb_direct);
1467
1468 sense_reason_t
1469 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1470 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1471 {
1472 if (!sgl || !sgl_count)
1473 return 0;
1474
1475 /*
1476 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1477 * scatterlists already have been set to follow what the fabric
1478 * passes for the original expected data transfer length.
1479 */
1480 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1481 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1482 " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1483 return TCM_INVALID_CDB_FIELD;
1484 }
1485
1486 cmd->t_data_sg = sgl;
1487 cmd->t_data_nents = sgl_count;
1488 cmd->t_bidi_data_sg = sgl_bidi;
1489 cmd->t_bidi_data_nents = sgl_bidi_count;
1490
1491 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1492 return 0;
1493 }
1494
1495 /**
1496 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1497 * se_cmd + use pre-allocated SGL memory.
1498 *
1499 * @se_cmd: command descriptor to submit
1500 * @se_sess: associated se_sess for endpoint
1501 * @cdb: pointer to SCSI CDB
1502 * @sense: pointer to SCSI sense buffer
1503 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1504 * @data_length: fabric expected data transfer length
1505 * @task_attr: SAM task attribute
1506 * @data_dir: DMA data direction
1507 * @flags: flags for command submission from target_sc_flags_tables
1508 * @sgl: struct scatterlist memory for unidirectional mapping
1509 * @sgl_count: scatterlist count for unidirectional mapping
1510 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1511 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1512 * @sgl_prot: struct scatterlist memory protection information
1513 * @sgl_prot_count: scatterlist count for protection information
1514 *
1515 * Task tags are supported if the caller has set @se_cmd->tag.
1516 *
1517 * Returns non zero to signal active I/O shutdown failure. All other
1518 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1519 * but still return zero here.
1520 *
1521 * This may only be called from process context, and also currently
1522 * assumes internal allocation of fabric payload buffer by target-core.
1523 */
1524 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1525 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1526 u32 data_length, int task_attr, int data_dir, int flags,
1527 struct scatterlist *sgl, u32 sgl_count,
1528 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1529 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1530 {
1531 struct se_portal_group *se_tpg;
1532 sense_reason_t rc;
1533 int ret;
1534
1535 se_tpg = se_sess->se_tpg;
1536 BUG_ON(!se_tpg);
1537 BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1538 BUG_ON(in_interrupt());
1539 /*
1540 * Initialize se_cmd for target operation. From this point
1541 * exceptions are handled by sending exception status via
1542 * target_core_fabric_ops->queue_status() callback
1543 */
1544 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1545 data_length, data_dir, task_attr, sense);
1546
1547 if (flags & TARGET_SCF_USE_CPUID)
1548 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1549 else
1550 se_cmd->cpuid = WORK_CPU_UNBOUND;
1551
1552 if (flags & TARGET_SCF_UNKNOWN_SIZE)
1553 se_cmd->unknown_data_length = 1;
1554 /*
1555 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1556 * se_sess->sess_cmd_list. A second kref_get here is necessary
1557 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1558 * kref_put() to happen during fabric packet acknowledgement.
1559 */
1560 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1561 if (ret)
1562 return ret;
1563 /*
1564 * Signal bidirectional data payloads to target-core
1565 */
1566 if (flags & TARGET_SCF_BIDI_OP)
1567 se_cmd->se_cmd_flags |= SCF_BIDI;
1568 /*
1569 * Locate se_lun pointer and attach it to struct se_cmd
1570 */
1571 rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1572 if (rc) {
1573 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1574 target_put_sess_cmd(se_cmd);
1575 return 0;
1576 }
1577
1578 rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1579 if (rc != 0) {
1580 transport_generic_request_failure(se_cmd, rc);
1581 return 0;
1582 }
1583
1584 /*
1585 * Save pointers for SGLs containing protection information,
1586 * if present.
1587 */
1588 if (sgl_prot_count) {
1589 se_cmd->t_prot_sg = sgl_prot;
1590 se_cmd->t_prot_nents = sgl_prot_count;
1591 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1592 }
1593
1594 /*
1595 * When a non zero sgl_count has been passed perform SGL passthrough
1596 * mapping for pre-allocated fabric memory instead of having target
1597 * core perform an internal SGL allocation..
1598 */
1599 if (sgl_count != 0) {
1600 BUG_ON(!sgl);
1601
1602 /*
1603 * A work-around for tcm_loop as some userspace code via
1604 * scsi-generic do not memset their associated read buffers,
1605 * so go ahead and do that here for type non-data CDBs. Also
1606 * note that this is currently guaranteed to be a single SGL
1607 * for this case by target core in target_setup_cmd_from_cdb()
1608 * -> transport_generic_cmd_sequencer().
1609 */
1610 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1611 se_cmd->data_direction == DMA_FROM_DEVICE) {
1612 unsigned char *buf = NULL;
1613
1614 if (sgl)
1615 buf = kmap(sg_page(sgl)) + sgl->offset;
1616
1617 if (buf) {
1618 memset(buf, 0, sgl->length);
1619 kunmap(sg_page(sgl));
1620 }
1621 }
1622
1623 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1624 sgl_bidi, sgl_bidi_count);
1625 if (rc != 0) {
1626 transport_generic_request_failure(se_cmd, rc);
1627 return 0;
1628 }
1629 }
1630
1631 /*
1632 * Check if we need to delay processing because of ALUA
1633 * Active/NonOptimized primary access state..
1634 */
1635 core_alua_check_nonop_delay(se_cmd);
1636
1637 transport_handle_cdb_direct(se_cmd);
1638 return 0;
1639 }
1640 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1641
1642 /**
1643 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1644 *
1645 * @se_cmd: command descriptor to submit
1646 * @se_sess: associated se_sess for endpoint
1647 * @cdb: pointer to SCSI CDB
1648 * @sense: pointer to SCSI sense buffer
1649 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1650 * @data_length: fabric expected data transfer length
1651 * @task_attr: SAM task attribute
1652 * @data_dir: DMA data direction
1653 * @flags: flags for command submission from target_sc_flags_tables
1654 *
1655 * Task tags are supported if the caller has set @se_cmd->tag.
1656 *
1657 * Returns non zero to signal active I/O shutdown failure. All other
1658 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1659 * but still return zero here.
1660 *
1661 * This may only be called from process context, and also currently
1662 * assumes internal allocation of fabric payload buffer by target-core.
1663 *
1664 * It also assumes interal target core SGL memory allocation.
1665 */
1666 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1667 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1668 u32 data_length, int task_attr, int data_dir, int flags)
1669 {
1670 return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1671 unpacked_lun, data_length, task_attr, data_dir,
1672 flags, NULL, 0, NULL, 0, NULL, 0);
1673 }
1674 EXPORT_SYMBOL(target_submit_cmd);
1675
1676 static void target_complete_tmr_failure(struct work_struct *work)
1677 {
1678 struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1679
1680 se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1681 se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1682
1683 transport_cmd_check_stop_to_fabric(se_cmd);
1684 }
1685
1686 static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
1687 u64 *unpacked_lun)
1688 {
1689 struct se_cmd *se_cmd;
1690 unsigned long flags;
1691 bool ret = false;
1692
1693 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
1694 list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
1695 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1696 continue;
1697
1698 if (se_cmd->tag == tag) {
1699 *unpacked_lun = se_cmd->orig_fe_lun;
1700 ret = true;
1701 break;
1702 }
1703 }
1704 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
1705
1706 return ret;
1707 }
1708
1709 /**
1710 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1711 * for TMR CDBs
1712 *
1713 * @se_cmd: command descriptor to submit
1714 * @se_sess: associated se_sess for endpoint
1715 * @sense: pointer to SCSI sense buffer
1716 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1717 * @fabric_tmr_ptr: fabric context for TMR req
1718 * @tm_type: Type of TM request
1719 * @gfp: gfp type for caller
1720 * @tag: referenced task tag for TMR_ABORT_TASK
1721 * @flags: submit cmd flags
1722 *
1723 * Callable from all contexts.
1724 **/
1725
1726 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1727 unsigned char *sense, u64 unpacked_lun,
1728 void *fabric_tmr_ptr, unsigned char tm_type,
1729 gfp_t gfp, u64 tag, int flags)
1730 {
1731 struct se_portal_group *se_tpg;
1732 int ret;
1733
1734 se_tpg = se_sess->se_tpg;
1735 BUG_ON(!se_tpg);
1736
1737 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1738 0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1739 /*
1740 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1741 * allocation failure.
1742 */
1743 ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1744 if (ret < 0)
1745 return -ENOMEM;
1746
1747 if (tm_type == TMR_ABORT_TASK)
1748 se_cmd->se_tmr_req->ref_task_tag = tag;
1749
1750 /* See target_submit_cmd for commentary */
1751 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1752 if (ret) {
1753 core_tmr_release_req(se_cmd->se_tmr_req);
1754 return ret;
1755 }
1756 /*
1757 * If this is ABORT_TASK with no explicit fabric provided LUN,
1758 * go ahead and search active session tags for a match to figure
1759 * out unpacked_lun for the original se_cmd.
1760 */
1761 if (tm_type == TMR_ABORT_TASK && (flags & TARGET_SCF_LOOKUP_LUN_FROM_TAG)) {
1762 if (!target_lookup_lun_from_tag(se_sess, tag, &unpacked_lun))
1763 goto failure;
1764 }
1765
1766 ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1767 if (ret)
1768 goto failure;
1769
1770 transport_generic_handle_tmr(se_cmd);
1771 return 0;
1772
1773 /*
1774 * For callback during failure handling, push this work off
1775 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1776 */
1777 failure:
1778 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1779 schedule_work(&se_cmd->work);
1780 return 0;
1781 }
1782 EXPORT_SYMBOL(target_submit_tmr);
1783
1784 /*
1785 * Handle SAM-esque emulation for generic transport request failures.
1786 */
1787 void transport_generic_request_failure(struct se_cmd *cmd,
1788 sense_reason_t sense_reason)
1789 {
1790 int ret = 0, post_ret;
1791
1792 pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
1793 sense_reason);
1794 target_show_cmd("-----[ ", cmd);
1795
1796 /*
1797 * For SAM Task Attribute emulation for failed struct se_cmd
1798 */
1799 transport_complete_task_attr(cmd);
1800
1801 if (cmd->transport_complete_callback)
1802 cmd->transport_complete_callback(cmd, false, &post_ret);
1803
1804 if (cmd->transport_state & CMD_T_ABORTED) {
1805 INIT_WORK(&cmd->work, target_abort_work);
1806 queue_work(target_completion_wq, &cmd->work);
1807 return;
1808 }
1809
1810 switch (sense_reason) {
1811 case TCM_NON_EXISTENT_LUN:
1812 case TCM_UNSUPPORTED_SCSI_OPCODE:
1813 case TCM_INVALID_CDB_FIELD:
1814 case TCM_INVALID_PARAMETER_LIST:
1815 case TCM_PARAMETER_LIST_LENGTH_ERROR:
1816 case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1817 case TCM_UNKNOWN_MODE_PAGE:
1818 case TCM_WRITE_PROTECTED:
1819 case TCM_ADDRESS_OUT_OF_RANGE:
1820 case TCM_CHECK_CONDITION_ABORT_CMD:
1821 case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1822 case TCM_CHECK_CONDITION_NOT_READY:
1823 case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1824 case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1825 case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1826 case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1827 case TCM_TOO_MANY_TARGET_DESCS:
1828 case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
1829 case TCM_TOO_MANY_SEGMENT_DESCS:
1830 case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
1831 break;
1832 case TCM_OUT_OF_RESOURCES:
1833 cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
1834 goto queue_status;
1835 case TCM_LUN_BUSY:
1836 cmd->scsi_status = SAM_STAT_BUSY;
1837 goto queue_status;
1838 case TCM_RESERVATION_CONFLICT:
1839 /*
1840 * No SENSE Data payload for this case, set SCSI Status
1841 * and queue the response to $FABRIC_MOD.
1842 *
1843 * Uses linux/include/scsi/scsi.h SAM status codes defs
1844 */
1845 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1846 /*
1847 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1848 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1849 * CONFLICT STATUS.
1850 *
1851 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1852 */
1853 if (cmd->se_sess &&
1854 cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1855 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1856 cmd->orig_fe_lun, 0x2C,
1857 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1858 }
1859
1860 goto queue_status;
1861 default:
1862 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1863 cmd->t_task_cdb[0], sense_reason);
1864 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1865 break;
1866 }
1867
1868 ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1869 if (ret)
1870 goto queue_full;
1871
1872 check_stop:
1873 transport_cmd_check_stop_to_fabric(cmd);
1874 return;
1875
1876 queue_status:
1877 trace_target_cmd_complete(cmd);
1878 ret = cmd->se_tfo->queue_status(cmd);
1879 if (!ret)
1880 goto check_stop;
1881 queue_full:
1882 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
1883 }
1884 EXPORT_SYMBOL(transport_generic_request_failure);
1885
1886 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1887 {
1888 sense_reason_t ret;
1889
1890 if (!cmd->execute_cmd) {
1891 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1892 goto err;
1893 }
1894 if (do_checks) {
1895 /*
1896 * Check for an existing UNIT ATTENTION condition after
1897 * target_handle_task_attr() has done SAM task attr
1898 * checking, and possibly have already defered execution
1899 * out to target_restart_delayed_cmds() context.
1900 */
1901 ret = target_scsi3_ua_check(cmd);
1902 if (ret)
1903 goto err;
1904
1905 ret = target_alua_state_check(cmd);
1906 if (ret)
1907 goto err;
1908
1909 ret = target_check_reservation(cmd);
1910 if (ret) {
1911 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1912 goto err;
1913 }
1914 }
1915
1916 ret = cmd->execute_cmd(cmd);
1917 if (!ret)
1918 return;
1919 err:
1920 spin_lock_irq(&cmd->t_state_lock);
1921 cmd->transport_state &= ~CMD_T_SENT;
1922 spin_unlock_irq(&cmd->t_state_lock);
1923
1924 transport_generic_request_failure(cmd, ret);
1925 }
1926
1927 static int target_write_prot_action(struct se_cmd *cmd)
1928 {
1929 u32 sectors;
1930 /*
1931 * Perform WRITE_INSERT of PI using software emulation when backend
1932 * device has PI enabled, if the transport has not already generated
1933 * PI using hardware WRITE_INSERT offload.
1934 */
1935 switch (cmd->prot_op) {
1936 case TARGET_PROT_DOUT_INSERT:
1937 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1938 sbc_dif_generate(cmd);
1939 break;
1940 case TARGET_PROT_DOUT_STRIP:
1941 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1942 break;
1943
1944 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1945 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1946 sectors, 0, cmd->t_prot_sg, 0);
1947 if (unlikely(cmd->pi_err)) {
1948 spin_lock_irq(&cmd->t_state_lock);
1949 cmd->transport_state &= ~CMD_T_SENT;
1950 spin_unlock_irq(&cmd->t_state_lock);
1951 transport_generic_request_failure(cmd, cmd->pi_err);
1952 return -1;
1953 }
1954 break;
1955 default:
1956 break;
1957 }
1958
1959 return 0;
1960 }
1961
1962 static bool target_handle_task_attr(struct se_cmd *cmd)
1963 {
1964 struct se_device *dev = cmd->se_dev;
1965
1966 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1967 return false;
1968
1969 cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
1970
1971 /*
1972 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1973 * to allow the passed struct se_cmd list of tasks to the front of the list.
1974 */
1975 switch (cmd->sam_task_attr) {
1976 case TCM_HEAD_TAG:
1977 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1978 cmd->t_task_cdb[0]);
1979 return false;
1980 case TCM_ORDERED_TAG:
1981 atomic_inc_mb(&dev->dev_ordered_sync);
1982
1983 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1984 cmd->t_task_cdb[0]);
1985
1986 /*
1987 * Execute an ORDERED command if no other older commands
1988 * exist that need to be completed first.
1989 */
1990 if (!atomic_read(&dev->simple_cmds))
1991 return false;
1992 break;
1993 default:
1994 /*
1995 * For SIMPLE and UNTAGGED Task Attribute commands
1996 */
1997 atomic_inc_mb(&dev->simple_cmds);
1998 break;
1999 }
2000
2001 if (atomic_read(&dev->dev_ordered_sync) == 0)
2002 return false;
2003
2004 spin_lock(&dev->delayed_cmd_lock);
2005 list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
2006 spin_unlock(&dev->delayed_cmd_lock);
2007
2008 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
2009 cmd->t_task_cdb[0], cmd->sam_task_attr);
2010 return true;
2011 }
2012
2013 void target_execute_cmd(struct se_cmd *cmd)
2014 {
2015 /*
2016 * Determine if frontend context caller is requesting the stopping of
2017 * this command for frontend exceptions.
2018 *
2019 * If the received CDB has already been aborted stop processing it here.
2020 */
2021 if (target_cmd_interrupted(cmd))
2022 return;
2023
2024 spin_lock_irq(&cmd->t_state_lock);
2025 cmd->t_state = TRANSPORT_PROCESSING;
2026 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
2027 spin_unlock_irq(&cmd->t_state_lock);
2028
2029 if (target_write_prot_action(cmd))
2030 return;
2031
2032 if (target_handle_task_attr(cmd)) {
2033 spin_lock_irq(&cmd->t_state_lock);
2034 cmd->transport_state &= ~CMD_T_SENT;
2035 spin_unlock_irq(&cmd->t_state_lock);
2036 return;
2037 }
2038
2039 __target_execute_cmd(cmd, true);
2040 }
2041 EXPORT_SYMBOL(target_execute_cmd);
2042
2043 /*
2044 * Process all commands up to the last received ORDERED task attribute which
2045 * requires another blocking boundary
2046 */
2047 static void target_restart_delayed_cmds(struct se_device *dev)
2048 {
2049 for (;;) {
2050 struct se_cmd *cmd;
2051
2052 spin_lock(&dev->delayed_cmd_lock);
2053 if (list_empty(&dev->delayed_cmd_list)) {
2054 spin_unlock(&dev->delayed_cmd_lock);
2055 break;
2056 }
2057
2058 cmd = list_entry(dev->delayed_cmd_list.next,
2059 struct se_cmd, se_delayed_node);
2060 list_del(&cmd->se_delayed_node);
2061 spin_unlock(&dev->delayed_cmd_lock);
2062
2063 cmd->transport_state |= CMD_T_SENT;
2064
2065 __target_execute_cmd(cmd, true);
2066
2067 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
2068 break;
2069 }
2070 }
2071
2072 /*
2073 * Called from I/O completion to determine which dormant/delayed
2074 * and ordered cmds need to have their tasks added to the execution queue.
2075 */
2076 static void transport_complete_task_attr(struct se_cmd *cmd)
2077 {
2078 struct se_device *dev = cmd->se_dev;
2079
2080 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2081 return;
2082
2083 if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2084 goto restart;
2085
2086 if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
2087 atomic_dec_mb(&dev->simple_cmds);
2088 dev->dev_cur_ordered_id++;
2089 } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
2090 dev->dev_cur_ordered_id++;
2091 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
2092 dev->dev_cur_ordered_id);
2093 } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2094 atomic_dec_mb(&dev->dev_ordered_sync);
2095
2096 dev->dev_cur_ordered_id++;
2097 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
2098 dev->dev_cur_ordered_id);
2099 }
2100 cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2101
2102 restart:
2103 target_restart_delayed_cmds(dev);
2104 }
2105
2106 static void transport_complete_qf(struct se_cmd *cmd)
2107 {
2108 int ret = 0;
2109
2110 transport_complete_task_attr(cmd);
2111 /*
2112 * If a fabric driver ->write_pending() or ->queue_data_in() callback
2113 * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2114 * the same callbacks should not be retried. Return CHECK_CONDITION
2115 * if a scsi_status is not already set.
2116 *
2117 * If a fabric driver ->queue_status() has returned non zero, always
2118 * keep retrying no matter what..
2119 */
2120 if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2121 if (cmd->scsi_status)
2122 goto queue_status;
2123
2124 translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2125 goto queue_status;
2126 }
2127
2128 /*
2129 * Check if we need to send a sense buffer from
2130 * the struct se_cmd in question. We do NOT want
2131 * to take this path of the IO has been marked as
2132 * needing to be treated like a "normal read". This
2133 * is the case if it's a tape read, and either the
2134 * FM, EOM, or ILI bits are set, but there is no
2135 * sense data.
2136 */
2137 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2138 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2139 goto queue_status;
2140
2141 switch (cmd->data_direction) {
2142 case DMA_FROM_DEVICE:
2143 /* queue status if not treating this as a normal read */
2144 if (cmd->scsi_status &&
2145 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2146 goto queue_status;
2147
2148 trace_target_cmd_complete(cmd);
2149 ret = cmd->se_tfo->queue_data_in(cmd);
2150 break;
2151 case DMA_TO_DEVICE:
2152 if (cmd->se_cmd_flags & SCF_BIDI) {
2153 ret = cmd->se_tfo->queue_data_in(cmd);
2154 break;
2155 }
2156 /* fall through */
2157 case DMA_NONE:
2158 queue_status:
2159 trace_target_cmd_complete(cmd);
2160 ret = cmd->se_tfo->queue_status(cmd);
2161 break;
2162 default:
2163 break;
2164 }
2165
2166 if (ret < 0) {
2167 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2168 return;
2169 }
2170 transport_cmd_check_stop_to_fabric(cmd);
2171 }
2172
2173 static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2174 int err, bool write_pending)
2175 {
2176 /*
2177 * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2178 * ->queue_data_in() callbacks from new process context.
2179 *
2180 * Otherwise for other errors, transport_complete_qf() will send
2181 * CHECK_CONDITION via ->queue_status() instead of attempting to
2182 * retry associated fabric driver data-transfer callbacks.
2183 */
2184 if (err == -EAGAIN || err == -ENOMEM) {
2185 cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2186 TRANSPORT_COMPLETE_QF_OK;
2187 } else {
2188 pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2189 cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2190 }
2191
2192 spin_lock_irq(&dev->qf_cmd_lock);
2193 list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2194 atomic_inc_mb(&dev->dev_qf_count);
2195 spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2196
2197 schedule_work(&cmd->se_dev->qf_work_queue);
2198 }
2199
2200 static bool target_read_prot_action(struct se_cmd *cmd)
2201 {
2202 switch (cmd->prot_op) {
2203 case TARGET_PROT_DIN_STRIP:
2204 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2205 u32 sectors = cmd->data_length >>
2206 ilog2(cmd->se_dev->dev_attrib.block_size);
2207
2208 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2209 sectors, 0, cmd->t_prot_sg,
2210 0);
2211 if (cmd->pi_err)
2212 return true;
2213 }
2214 break;
2215 case TARGET_PROT_DIN_INSERT:
2216 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2217 break;
2218
2219 sbc_dif_generate(cmd);
2220 break;
2221 default:
2222 break;
2223 }
2224
2225 return false;
2226 }
2227
2228 static void target_complete_ok_work(struct work_struct *work)
2229 {
2230 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2231 int ret;
2232
2233 /*
2234 * Check if we need to move delayed/dormant tasks from cmds on the
2235 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2236 * Attribute.
2237 */
2238 transport_complete_task_attr(cmd);
2239
2240 /*
2241 * Check to schedule QUEUE_FULL work, or execute an existing
2242 * cmd->transport_qf_callback()
2243 */
2244 if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2245 schedule_work(&cmd->se_dev->qf_work_queue);
2246
2247 /*
2248 * Check if we need to send a sense buffer from
2249 * the struct se_cmd in question. We do NOT want
2250 * to take this path of the IO has been marked as
2251 * needing to be treated like a "normal read". This
2252 * is the case if it's a tape read, and either the
2253 * FM, EOM, or ILI bits are set, but there is no
2254 * sense data.
2255 */
2256 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2257 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2258 WARN_ON(!cmd->scsi_status);
2259 ret = transport_send_check_condition_and_sense(
2260 cmd, 0, 1);
2261 if (ret)
2262 goto queue_full;
2263
2264 transport_cmd_check_stop_to_fabric(cmd);
2265 return;
2266 }
2267 /*
2268 * Check for a callback, used by amongst other things
2269 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2270 */
2271 if (cmd->transport_complete_callback) {
2272 sense_reason_t rc;
2273 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2274 bool zero_dl = !(cmd->data_length);
2275 int post_ret = 0;
2276
2277 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2278 if (!rc && !post_ret) {
2279 if (caw && zero_dl)
2280 goto queue_rsp;
2281
2282 return;
2283 } else if (rc) {
2284 ret = transport_send_check_condition_and_sense(cmd,
2285 rc, 0);
2286 if (ret)
2287 goto queue_full;
2288
2289 transport_cmd_check_stop_to_fabric(cmd);
2290 return;
2291 }
2292 }
2293
2294 queue_rsp:
2295 switch (cmd->data_direction) {
2296 case DMA_FROM_DEVICE:
2297 /*
2298 * if this is a READ-type IO, but SCSI status
2299 * is set, then skip returning data and just
2300 * return the status -- unless this IO is marked
2301 * as needing to be treated as a normal read,
2302 * in which case we want to go ahead and return
2303 * the data. This happens, for example, for tape
2304 * reads with the FM, EOM, or ILI bits set, with
2305 * no sense data.
2306 */
2307 if (cmd->scsi_status &&
2308 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2309 goto queue_status;
2310
2311 atomic_long_add(cmd->data_length,
2312 &cmd->se_lun->lun_stats.tx_data_octets);
2313 /*
2314 * Perform READ_STRIP of PI using software emulation when
2315 * backend had PI enabled, if the transport will not be
2316 * performing hardware READ_STRIP offload.
2317 */
2318 if (target_read_prot_action(cmd)) {
2319 ret = transport_send_check_condition_and_sense(cmd,
2320 cmd->pi_err, 0);
2321 if (ret)
2322 goto queue_full;
2323
2324 transport_cmd_check_stop_to_fabric(cmd);
2325 return;
2326 }
2327
2328 trace_target_cmd_complete(cmd);
2329 ret = cmd->se_tfo->queue_data_in(cmd);
2330 if (ret)
2331 goto queue_full;
2332 break;
2333 case DMA_TO_DEVICE:
2334 atomic_long_add(cmd->data_length,
2335 &cmd->se_lun->lun_stats.rx_data_octets);
2336 /*
2337 * Check if we need to send READ payload for BIDI-COMMAND
2338 */
2339 if (cmd->se_cmd_flags & SCF_BIDI) {
2340 atomic_long_add(cmd->data_length,
2341 &cmd->se_lun->lun_stats.tx_data_octets);
2342 ret = cmd->se_tfo->queue_data_in(cmd);
2343 if (ret)
2344 goto queue_full;
2345 break;
2346 }
2347 /* fall through */
2348 case DMA_NONE:
2349 queue_status:
2350 trace_target_cmd_complete(cmd);
2351 ret = cmd->se_tfo->queue_status(cmd);
2352 if (ret)
2353 goto queue_full;
2354 break;
2355 default:
2356 break;
2357 }
2358
2359 transport_cmd_check_stop_to_fabric(cmd);
2360 return;
2361
2362 queue_full:
2363 pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2364 " data_direction: %d\n", cmd, cmd->data_direction);
2365
2366 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2367 }
2368
2369 void target_free_sgl(struct scatterlist *sgl, int nents)
2370 {
2371 sgl_free_n_order(sgl, nents, 0);
2372 }
2373 EXPORT_SYMBOL(target_free_sgl);
2374
2375 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2376 {
2377 /*
2378 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2379 * emulation, and free + reset pointers if necessary..
2380 */
2381 if (!cmd->t_data_sg_orig)
2382 return;
2383
2384 kfree(cmd->t_data_sg);
2385 cmd->t_data_sg = cmd->t_data_sg_orig;
2386 cmd->t_data_sg_orig = NULL;
2387 cmd->t_data_nents = cmd->t_data_nents_orig;
2388 cmd->t_data_nents_orig = 0;
2389 }
2390
2391 static inline void transport_free_pages(struct se_cmd *cmd)
2392 {
2393 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2394 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2395 cmd->t_prot_sg = NULL;
2396 cmd->t_prot_nents = 0;
2397 }
2398
2399 if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2400 /*
2401 * Release special case READ buffer payload required for
2402 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2403 */
2404 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2405 target_free_sgl(cmd->t_bidi_data_sg,
2406 cmd->t_bidi_data_nents);
2407 cmd->t_bidi_data_sg = NULL;
2408 cmd->t_bidi_data_nents = 0;
2409 }
2410 transport_reset_sgl_orig(cmd);
2411 return;
2412 }
2413 transport_reset_sgl_orig(cmd);
2414
2415 target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2416 cmd->t_data_sg = NULL;
2417 cmd->t_data_nents = 0;
2418
2419 target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2420 cmd->t_bidi_data_sg = NULL;
2421 cmd->t_bidi_data_nents = 0;
2422 }
2423
2424 void *transport_kmap_data_sg(struct se_cmd *cmd)
2425 {
2426 struct scatterlist *sg = cmd->t_data_sg;
2427 struct page **pages;
2428 int i;
2429
2430 /*
2431 * We need to take into account a possible offset here for fabrics like
2432 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2433 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2434 */
2435 if (!cmd->t_data_nents)
2436 return NULL;
2437
2438 BUG_ON(!sg);
2439 if (cmd->t_data_nents == 1)
2440 return kmap(sg_page(sg)) + sg->offset;
2441
2442 /* >1 page. use vmap */
2443 pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2444 if (!pages)
2445 return NULL;
2446
2447 /* convert sg[] to pages[] */
2448 for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2449 pages[i] = sg_page(sg);
2450 }
2451
2452 cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
2453 kfree(pages);
2454 if (!cmd->t_data_vmap)
2455 return NULL;
2456
2457 return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2458 }
2459 EXPORT_SYMBOL(transport_kmap_data_sg);
2460
2461 void transport_kunmap_data_sg(struct se_cmd *cmd)
2462 {
2463 if (!cmd->t_data_nents) {
2464 return;
2465 } else if (cmd->t_data_nents == 1) {
2466 kunmap(sg_page(cmd->t_data_sg));
2467 return;
2468 }
2469
2470 vunmap(cmd->t_data_vmap);
2471 cmd->t_data_vmap = NULL;
2472 }
2473 EXPORT_SYMBOL(transport_kunmap_data_sg);
2474
2475 int
2476 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2477 bool zero_page, bool chainable)
2478 {
2479 gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2480
2481 *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2482 return *sgl ? 0 : -ENOMEM;
2483 }
2484 EXPORT_SYMBOL(target_alloc_sgl);
2485
2486 /*
2487 * Allocate any required resources to execute the command. For writes we
2488 * might not have the payload yet, so notify the fabric via a call to
2489 * ->write_pending instead. Otherwise place it on the execution queue.
2490 */
2491 sense_reason_t
2492 transport_generic_new_cmd(struct se_cmd *cmd)
2493 {
2494 unsigned long flags;
2495 int ret = 0;
2496 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2497
2498 if (cmd->prot_op != TARGET_PROT_NORMAL &&
2499 !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2500 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2501 cmd->prot_length, true, false);
2502 if (ret < 0)
2503 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2504 }
2505
2506 /*
2507 * Determine if the TCM fabric module has already allocated physical
2508 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2509 * beforehand.
2510 */
2511 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2512 cmd->data_length) {
2513
2514 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2515 (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2516 u32 bidi_length;
2517
2518 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2519 bidi_length = cmd->t_task_nolb *
2520 cmd->se_dev->dev_attrib.block_size;
2521 else
2522 bidi_length = cmd->data_length;
2523
2524 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2525 &cmd->t_bidi_data_nents,
2526 bidi_length, zero_flag, false);
2527 if (ret < 0)
2528 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2529 }
2530
2531 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2532 cmd->data_length, zero_flag, false);
2533 if (ret < 0)
2534 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2535 } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2536 cmd->data_length) {
2537 /*
2538 * Special case for COMPARE_AND_WRITE with fabrics
2539 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2540 */
2541 u32 caw_length = cmd->t_task_nolb *
2542 cmd->se_dev->dev_attrib.block_size;
2543
2544 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2545 &cmd->t_bidi_data_nents,
2546 caw_length, zero_flag, false);
2547 if (ret < 0)
2548 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2549 }
2550 /*
2551 * If this command is not a write we can execute it right here,
2552 * for write buffers we need to notify the fabric driver first
2553 * and let it call back once the write buffers are ready.
2554 */
2555 target_add_to_state_list(cmd);
2556 if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2557 target_execute_cmd(cmd);
2558 return 0;
2559 }
2560
2561 spin_lock_irqsave(&cmd->t_state_lock, flags);
2562 cmd->t_state = TRANSPORT_WRITE_PENDING;
2563 /*
2564 * Determine if frontend context caller is requesting the stopping of
2565 * this command for frontend exceptions.
2566 */
2567 if (cmd->transport_state & CMD_T_STOP &&
2568 !cmd->se_tfo->write_pending_must_be_called) {
2569 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2570 __func__, __LINE__, cmd->tag);
2571
2572 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2573
2574 complete_all(&cmd->t_transport_stop_comp);
2575 return 0;
2576 }
2577 cmd->transport_state &= ~CMD_T_ACTIVE;
2578 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2579
2580 ret = cmd->se_tfo->write_pending(cmd);
2581 if (ret)
2582 goto queue_full;
2583
2584 return 0;
2585
2586 queue_full:
2587 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2588 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2589 return 0;
2590 }
2591 EXPORT_SYMBOL(transport_generic_new_cmd);
2592
2593 static void transport_write_pending_qf(struct se_cmd *cmd)
2594 {
2595 unsigned long flags;
2596 int ret;
2597 bool stop;
2598
2599 spin_lock_irqsave(&cmd->t_state_lock, flags);
2600 stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2601 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2602
2603 if (stop) {
2604 pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2605 __func__, __LINE__, cmd->tag);
2606 complete_all(&cmd->t_transport_stop_comp);
2607 return;
2608 }
2609
2610 ret = cmd->se_tfo->write_pending(cmd);
2611 if (ret) {
2612 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2613 cmd);
2614 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2615 }
2616 }
2617
2618 static bool
2619 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2620 unsigned long *flags);
2621
2622 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2623 {
2624 unsigned long flags;
2625
2626 spin_lock_irqsave(&cmd->t_state_lock, flags);
2627 __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2628 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2629 }
2630
2631 /*
2632 * Call target_put_sess_cmd() and wait until target_release_cmd_kref(@cmd) has
2633 * finished.
2634 */
2635 void target_put_cmd_and_wait(struct se_cmd *cmd)
2636 {
2637 DECLARE_COMPLETION_ONSTACK(compl);
2638
2639 WARN_ON_ONCE(cmd->abrt_compl);
2640 cmd->abrt_compl = &compl;
2641 target_put_sess_cmd(cmd);
2642 wait_for_completion(&compl);
2643 }
2644
2645 /*
2646 * This function is called by frontend drivers after processing of a command
2647 * has finished.
2648 *
2649 * The protocol for ensuring that either the regular frontend command
2650 * processing flow or target_handle_abort() code drops one reference is as
2651 * follows:
2652 * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
2653 * the frontend driver to call this function synchronously or asynchronously.
2654 * That will cause one reference to be dropped.
2655 * - During regular command processing the target core sets CMD_T_COMPLETE
2656 * before invoking one of the .queue_*() functions.
2657 * - The code that aborts commands skips commands and TMFs for which
2658 * CMD_T_COMPLETE has been set.
2659 * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
2660 * commands that will be aborted.
2661 * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
2662 * transport_generic_free_cmd() skips its call to target_put_sess_cmd().
2663 * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
2664 * be called and will drop a reference.
2665 * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
2666 * will be called. target_handle_abort() will drop the final reference.
2667 */
2668 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2669 {
2670 DECLARE_COMPLETION_ONSTACK(compl);
2671 int ret = 0;
2672 bool aborted = false, tas = false;
2673
2674 if (wait_for_tasks)
2675 target_wait_free_cmd(cmd, &aborted, &tas);
2676
2677 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
2678 /*
2679 * Handle WRITE failure case where transport_generic_new_cmd()
2680 * has already added se_cmd to state_list, but fabric has
2681 * failed command before I/O submission.
2682 */
2683 if (cmd->state_active)
2684 target_remove_from_state_list(cmd);
2685 }
2686 if (aborted)
2687 cmd->free_compl = &compl;
2688 ret = target_put_sess_cmd(cmd);
2689 if (aborted) {
2690 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2691 wait_for_completion(&compl);
2692 ret = 1;
2693 }
2694 return ret;
2695 }
2696 EXPORT_SYMBOL(transport_generic_free_cmd);
2697
2698 /**
2699 * target_get_sess_cmd - Add command to active ->sess_cmd_list
2700 * @se_cmd: command descriptor to add
2701 * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
2702 */
2703 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2704 {
2705 struct se_session *se_sess = se_cmd->se_sess;
2706 unsigned long flags;
2707 int ret = 0;
2708
2709 /*
2710 * Add a second kref if the fabric caller is expecting to handle
2711 * fabric acknowledgement that requires two target_put_sess_cmd()
2712 * invocations before se_cmd descriptor release.
2713 */
2714 if (ack_kref) {
2715 if (!kref_get_unless_zero(&se_cmd->cmd_kref))
2716 return -EINVAL;
2717
2718 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2719 }
2720
2721 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2722 if (se_sess->sess_tearing_down) {
2723 ret = -ESHUTDOWN;
2724 goto out;
2725 }
2726 list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2727 percpu_ref_get(&se_sess->cmd_count);
2728 out:
2729 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2730
2731 if (ret && ack_kref)
2732 target_put_sess_cmd(se_cmd);
2733
2734 return ret;
2735 }
2736 EXPORT_SYMBOL(target_get_sess_cmd);
2737
2738 static void target_free_cmd_mem(struct se_cmd *cmd)
2739 {
2740 transport_free_pages(cmd);
2741
2742 if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2743 core_tmr_release_req(cmd->se_tmr_req);
2744 if (cmd->t_task_cdb != cmd->__t_task_cdb)
2745 kfree(cmd->t_task_cdb);
2746 }
2747
2748 static void target_release_cmd_kref(struct kref *kref)
2749 {
2750 struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2751 struct se_session *se_sess = se_cmd->se_sess;
2752 struct completion *free_compl = se_cmd->free_compl;
2753 struct completion *abrt_compl = se_cmd->abrt_compl;
2754 unsigned long flags;
2755
2756 if (se_cmd->lun_ref_active)
2757 percpu_ref_put(&se_cmd->se_lun->lun_ref);
2758
2759 if (se_sess) {
2760 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2761 list_del_init(&se_cmd->se_cmd_list);
2762 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2763 }
2764
2765 target_free_cmd_mem(se_cmd);
2766 se_cmd->se_tfo->release_cmd(se_cmd);
2767 if (free_compl)
2768 complete(free_compl);
2769 if (abrt_compl)
2770 complete(abrt_compl);
2771
2772 percpu_ref_put(&se_sess->cmd_count);
2773 }
2774
2775 /**
2776 * target_put_sess_cmd - decrease the command reference count
2777 * @se_cmd: command to drop a reference from
2778 *
2779 * Returns 1 if and only if this target_put_sess_cmd() call caused the
2780 * refcount to drop to zero. Returns zero otherwise.
2781 */
2782 int target_put_sess_cmd(struct se_cmd *se_cmd)
2783 {
2784 return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2785 }
2786 EXPORT_SYMBOL(target_put_sess_cmd);
2787
2788 static const char *data_dir_name(enum dma_data_direction d)
2789 {
2790 switch (d) {
2791 case DMA_BIDIRECTIONAL: return "BIDI";
2792 case DMA_TO_DEVICE: return "WRITE";
2793 case DMA_FROM_DEVICE: return "READ";
2794 case DMA_NONE: return "NONE";
2795 }
2796
2797 return "(?)";
2798 }
2799
2800 static const char *cmd_state_name(enum transport_state_table t)
2801 {
2802 switch (t) {
2803 case TRANSPORT_NO_STATE: return "NO_STATE";
2804 case TRANSPORT_NEW_CMD: return "NEW_CMD";
2805 case TRANSPORT_WRITE_PENDING: return "WRITE_PENDING";
2806 case TRANSPORT_PROCESSING: return "PROCESSING";
2807 case TRANSPORT_COMPLETE: return "COMPLETE";
2808 case TRANSPORT_ISTATE_PROCESSING:
2809 return "ISTATE_PROCESSING";
2810 case TRANSPORT_COMPLETE_QF_WP: return "COMPLETE_QF_WP";
2811 case TRANSPORT_COMPLETE_QF_OK: return "COMPLETE_QF_OK";
2812 case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR";
2813 }
2814
2815 return "(?)";
2816 }
2817
2818 static void target_append_str(char **str, const char *txt)
2819 {
2820 char *prev = *str;
2821
2822 *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
2823 kstrdup(txt, GFP_ATOMIC);
2824 kfree(prev);
2825 }
2826
2827 /*
2828 * Convert a transport state bitmask into a string. The caller is
2829 * responsible for freeing the returned pointer.
2830 */
2831 static char *target_ts_to_str(u32 ts)
2832 {
2833 char *str = NULL;
2834
2835 if (ts & CMD_T_ABORTED)
2836 target_append_str(&str, "aborted");
2837 if (ts & CMD_T_ACTIVE)
2838 target_append_str(&str, "active");
2839 if (ts & CMD_T_COMPLETE)
2840 target_append_str(&str, "complete");
2841 if (ts & CMD_T_SENT)
2842 target_append_str(&str, "sent");
2843 if (ts & CMD_T_STOP)
2844 target_append_str(&str, "stop");
2845 if (ts & CMD_T_FABRIC_STOP)
2846 target_append_str(&str, "fabric_stop");
2847
2848 return str;
2849 }
2850
2851 static const char *target_tmf_name(enum tcm_tmreq_table tmf)
2852 {
2853 switch (tmf) {
2854 case TMR_ABORT_TASK: return "ABORT_TASK";
2855 case TMR_ABORT_TASK_SET: return "ABORT_TASK_SET";
2856 case TMR_CLEAR_ACA: return "CLEAR_ACA";
2857 case TMR_CLEAR_TASK_SET: return "CLEAR_TASK_SET";
2858 case TMR_LUN_RESET: return "LUN_RESET";
2859 case TMR_TARGET_WARM_RESET: return "TARGET_WARM_RESET";
2860 case TMR_TARGET_COLD_RESET: return "TARGET_COLD_RESET";
2861 case TMR_UNKNOWN: break;
2862 }
2863 return "(?)";
2864 }
2865
2866 void target_show_cmd(const char *pfx, struct se_cmd *cmd)
2867 {
2868 char *ts_str = target_ts_to_str(cmd->transport_state);
2869 const u8 *cdb = cmd->t_task_cdb;
2870 struct se_tmr_req *tmf = cmd->se_tmr_req;
2871
2872 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2873 pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
2874 pfx, cdb[0], cdb[1], cmd->tag,
2875 data_dir_name(cmd->data_direction),
2876 cmd->se_tfo->get_cmd_state(cmd),
2877 cmd_state_name(cmd->t_state), cmd->data_length,
2878 kref_read(&cmd->cmd_kref), ts_str);
2879 } else {
2880 pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
2881 pfx, target_tmf_name(tmf->function), cmd->tag,
2882 tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
2883 cmd_state_name(cmd->t_state),
2884 kref_read(&cmd->cmd_kref), ts_str);
2885 }
2886 kfree(ts_str);
2887 }
2888 EXPORT_SYMBOL(target_show_cmd);
2889
2890 /**
2891 * target_sess_cmd_list_set_waiting - Set sess_tearing_down so no new commands are queued.
2892 * @se_sess: session to flag
2893 */
2894 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2895 {
2896 unsigned long flags;
2897
2898 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2899 se_sess->sess_tearing_down = 1;
2900 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2901
2902 percpu_ref_kill(&se_sess->cmd_count);
2903 }
2904 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2905
2906 /**
2907 * target_wait_for_sess_cmds - Wait for outstanding commands
2908 * @se_sess: session to wait for active I/O
2909 */
2910 void target_wait_for_sess_cmds(struct se_session *se_sess)
2911 {
2912 struct se_cmd *cmd;
2913 int ret;
2914
2915 WARN_ON_ONCE(!se_sess->sess_tearing_down);
2916
2917 do {
2918 ret = wait_event_timeout(se_sess->cmd_list_wq,
2919 percpu_ref_is_zero(&se_sess->cmd_count),
2920 180 * HZ);
2921 list_for_each_entry(cmd, &se_sess->sess_cmd_list, se_cmd_list)
2922 target_show_cmd("session shutdown: still waiting for ",
2923 cmd);
2924 } while (ret <= 0);
2925 }
2926 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2927
2928 /*
2929 * Prevent that new percpu_ref_tryget_live() calls succeed and wait until
2930 * all references to the LUN have been released. Called during LUN shutdown.
2931 */
2932 void transport_clear_lun_ref(struct se_lun *lun)
2933 {
2934 percpu_ref_kill(&lun->lun_ref);
2935 wait_for_completion(&lun->lun_shutdown_comp);
2936 }
2937
2938 static bool
2939 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2940 bool *aborted, bool *tas, unsigned long *flags)
2941 __releases(&cmd->t_state_lock)
2942 __acquires(&cmd->t_state_lock)
2943 {
2944
2945 assert_spin_locked(&cmd->t_state_lock);
2946 WARN_ON_ONCE(!irqs_disabled());
2947
2948 if (fabric_stop)
2949 cmd->transport_state |= CMD_T_FABRIC_STOP;
2950
2951 if (cmd->transport_state & CMD_T_ABORTED)
2952 *aborted = true;
2953
2954 if (cmd->transport_state & CMD_T_TAS)
2955 *tas = true;
2956
2957 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2958 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2959 return false;
2960
2961 if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2962 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2963 return false;
2964
2965 if (!(cmd->transport_state & CMD_T_ACTIVE))
2966 return false;
2967
2968 if (fabric_stop && *aborted)
2969 return false;
2970
2971 cmd->transport_state |= CMD_T_STOP;
2972
2973 target_show_cmd("wait_for_tasks: Stopping ", cmd);
2974
2975 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2976
2977 while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
2978 180 * HZ))
2979 target_show_cmd("wait for tasks: ", cmd);
2980
2981 spin_lock_irqsave(&cmd->t_state_lock, *flags);
2982 cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2983
2984 pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
2985 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
2986
2987 return true;
2988 }
2989
2990 /**
2991 * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
2992 * @cmd: command to wait on
2993 */
2994 bool transport_wait_for_tasks(struct se_cmd *cmd)
2995 {
2996 unsigned long flags;
2997 bool ret, aborted = false, tas = false;
2998
2999 spin_lock_irqsave(&cmd->t_state_lock, flags);
3000 ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
3001 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3002
3003 return ret;
3004 }
3005 EXPORT_SYMBOL(transport_wait_for_tasks);
3006
3007 struct sense_info {
3008 u8 key;
3009 u8 asc;
3010 u8 ascq;
3011 bool add_sector_info;
3012 };
3013
3014 static const struct sense_info sense_info_table[] = {
3015 [TCM_NO_SENSE] = {
3016 .key = NOT_READY
3017 },
3018 [TCM_NON_EXISTENT_LUN] = {
3019 .key = ILLEGAL_REQUEST,
3020 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
3021 },
3022 [TCM_UNSUPPORTED_SCSI_OPCODE] = {
3023 .key = ILLEGAL_REQUEST,
3024 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3025 },
3026 [TCM_SECTOR_COUNT_TOO_MANY] = {
3027 .key = ILLEGAL_REQUEST,
3028 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3029 },
3030 [TCM_UNKNOWN_MODE_PAGE] = {
3031 .key = ILLEGAL_REQUEST,
3032 .asc = 0x24, /* INVALID FIELD IN CDB */
3033 },
3034 [TCM_CHECK_CONDITION_ABORT_CMD] = {
3035 .key = ABORTED_COMMAND,
3036 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3037 .ascq = 0x03,
3038 },
3039 [TCM_INCORRECT_AMOUNT_OF_DATA] = {
3040 .key = ABORTED_COMMAND,
3041 .asc = 0x0c, /* WRITE ERROR */
3042 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3043 },
3044 [TCM_INVALID_CDB_FIELD] = {
3045 .key = ILLEGAL_REQUEST,
3046 .asc = 0x24, /* INVALID FIELD IN CDB */
3047 },
3048 [TCM_INVALID_PARAMETER_LIST] = {
3049 .key = ILLEGAL_REQUEST,
3050 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3051 },
3052 [TCM_TOO_MANY_TARGET_DESCS] = {
3053 .key = ILLEGAL_REQUEST,
3054 .asc = 0x26,
3055 .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3056 },
3057 [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3058 .key = ILLEGAL_REQUEST,
3059 .asc = 0x26,
3060 .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3061 },
3062 [TCM_TOO_MANY_SEGMENT_DESCS] = {
3063 .key = ILLEGAL_REQUEST,
3064 .asc = 0x26,
3065 .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3066 },
3067 [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3068 .key = ILLEGAL_REQUEST,
3069 .asc = 0x26,
3070 .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3071 },
3072 [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3073 .key = ILLEGAL_REQUEST,
3074 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3075 },
3076 [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3077 .key = ILLEGAL_REQUEST,
3078 .asc = 0x0c, /* WRITE ERROR */
3079 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3080 },
3081 [TCM_SERVICE_CRC_ERROR] = {
3082 .key = ABORTED_COMMAND,
3083 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3084 .ascq = 0x05, /* N/A */
3085 },
3086 [TCM_SNACK_REJECTED] = {
3087 .key = ABORTED_COMMAND,
3088 .asc = 0x11, /* READ ERROR */
3089 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3090 },
3091 [TCM_WRITE_PROTECTED] = {
3092 .key = DATA_PROTECT,
3093 .asc = 0x27, /* WRITE PROTECTED */
3094 },
3095 [TCM_ADDRESS_OUT_OF_RANGE] = {
3096 .key = ILLEGAL_REQUEST,
3097 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3098 },
3099 [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3100 .key = UNIT_ATTENTION,
3101 },
3102 [TCM_CHECK_CONDITION_NOT_READY] = {
3103 .key = NOT_READY,
3104 },
3105 [TCM_MISCOMPARE_VERIFY] = {
3106 .key = MISCOMPARE,
3107 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3108 .ascq = 0x00,
3109 },
3110 [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
3111 .key = ABORTED_COMMAND,
3112 .asc = 0x10,
3113 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
3114 .add_sector_info = true,
3115 },
3116 [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
3117 .key = ABORTED_COMMAND,
3118 .asc = 0x10,
3119 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
3120 .add_sector_info = true,
3121 },
3122 [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
3123 .key = ABORTED_COMMAND,
3124 .asc = 0x10,
3125 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
3126 .add_sector_info = true,
3127 },
3128 [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
3129 .key = COPY_ABORTED,
3130 .asc = 0x0d,
3131 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
3132
3133 },
3134 [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
3135 /*
3136 * Returning ILLEGAL REQUEST would cause immediate IO errors on
3137 * Solaris initiators. Returning NOT READY instead means the
3138 * operations will be retried a finite number of times and we
3139 * can survive intermittent errors.
3140 */
3141 .key = NOT_READY,
3142 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
3143 },
3144 [TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
3145 /*
3146 * From spc4r22 section5.7.7,5.7.8
3147 * If a PERSISTENT RESERVE OUT command with a REGISTER service action
3148 * or a REGISTER AND IGNORE EXISTING KEY service action or
3149 * REGISTER AND MOVE service actionis attempted,
3150 * but there are insufficient device server resources to complete the
3151 * operation, then the command shall be terminated with CHECK CONDITION
3152 * status, with the sense key set to ILLEGAL REQUEST,and the additonal
3153 * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
3154 */
3155 .key = ILLEGAL_REQUEST,
3156 .asc = 0x55,
3157 .ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
3158 },
3159 };
3160
3161 /**
3162 * translate_sense_reason - translate a sense reason into T10 key, asc and ascq
3163 * @cmd: SCSI command in which the resulting sense buffer or SCSI status will
3164 * be stored.
3165 * @reason: LIO sense reason code. If this argument has the value
3166 * TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If
3167 * dequeuing a unit attention fails due to multiple commands being processed
3168 * concurrently, set the command status to BUSY.
3169 *
3170 * Return: 0 upon success or -EINVAL if the sense buffer is too small.
3171 */
3172 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
3173 {
3174 const struct sense_info *si;
3175 u8 *buffer = cmd->sense_buffer;
3176 int r = (__force int)reason;
3177 u8 key, asc, ascq;
3178 bool desc_format = target_sense_desc_format(cmd->se_dev);
3179
3180 if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
3181 si = &sense_info_table[r];
3182 else
3183 si = &sense_info_table[(__force int)
3184 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3185
3186 key = si->key;
3187 if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
3188 if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc,
3189 &ascq)) {
3190 cmd->scsi_status = SAM_STAT_BUSY;
3191 return;
3192 }
3193 } else if (si->asc == 0) {
3194 WARN_ON_ONCE(cmd->scsi_asc == 0);
3195 asc = cmd->scsi_asc;
3196 ascq = cmd->scsi_ascq;
3197 } else {
3198 asc = si->asc;
3199 ascq = si->ascq;
3200 }
3201
3202 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
3203 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
3204 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
3205 scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
3206 if (si->add_sector_info)
3207 WARN_ON_ONCE(scsi_set_sense_information(buffer,
3208 cmd->scsi_sense_length,
3209 cmd->bad_sector) < 0);
3210 }
3211
3212 int
3213 transport_send_check_condition_and_sense(struct se_cmd *cmd,
3214 sense_reason_t reason, int from_transport)
3215 {
3216 unsigned long flags;
3217
3218 WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3219
3220 spin_lock_irqsave(&cmd->t_state_lock, flags);
3221 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
3222 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3223 return 0;
3224 }
3225 cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
3226 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3227
3228 if (!from_transport)
3229 translate_sense_reason(cmd, reason);
3230
3231 trace_target_cmd_complete(cmd);
3232 return cmd->se_tfo->queue_status(cmd);
3233 }
3234 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
3235
3236 /**
3237 * target_send_busy - Send SCSI BUSY status back to the initiator
3238 * @cmd: SCSI command for which to send a BUSY reply.
3239 *
3240 * Note: Only call this function if target_submit_cmd*() failed.
3241 */
3242 int target_send_busy(struct se_cmd *cmd)
3243 {
3244 WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3245
3246 cmd->scsi_status = SAM_STAT_BUSY;
3247 trace_target_cmd_complete(cmd);
3248 return cmd->se_tfo->queue_status(cmd);
3249 }
3250 EXPORT_SYMBOL(target_send_busy);
3251
3252 static void target_tmr_work(struct work_struct *work)
3253 {
3254 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3255 struct se_device *dev = cmd->se_dev;
3256 struct se_tmr_req *tmr = cmd->se_tmr_req;
3257 int ret;
3258
3259 if (cmd->transport_state & CMD_T_ABORTED)
3260 goto aborted;
3261
3262 switch (tmr->function) {
3263 case TMR_ABORT_TASK:
3264 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3265 break;
3266 case TMR_ABORT_TASK_SET:
3267 case TMR_CLEAR_ACA:
3268 case TMR_CLEAR_TASK_SET:
3269 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3270 break;
3271 case TMR_LUN_RESET:
3272 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3273 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3274 TMR_FUNCTION_REJECTED;
3275 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3276 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3277 cmd->orig_fe_lun, 0x29,
3278 ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3279 }
3280 break;
3281 case TMR_TARGET_WARM_RESET:
3282 tmr->response = TMR_FUNCTION_REJECTED;
3283 break;
3284 case TMR_TARGET_COLD_RESET:
3285 tmr->response = TMR_FUNCTION_REJECTED;
3286 break;
3287 default:
3288 pr_err("Unknown TMR function: 0x%02x.\n",
3289 tmr->function);
3290 tmr->response = TMR_FUNCTION_REJECTED;
3291 break;
3292 }
3293
3294 if (cmd->transport_state & CMD_T_ABORTED)
3295 goto aborted;
3296
3297 cmd->se_tfo->queue_tm_rsp(cmd);
3298
3299 transport_cmd_check_stop_to_fabric(cmd);
3300 return;
3301
3302 aborted:
3303 target_handle_abort(cmd);
3304 }
3305
3306 int transport_generic_handle_tmr(
3307 struct se_cmd *cmd)
3308 {
3309 unsigned long flags;
3310 bool aborted = false;
3311
3312 spin_lock_irqsave(&cmd->t_state_lock, flags);
3313 if (cmd->transport_state & CMD_T_ABORTED) {
3314 aborted = true;
3315 } else {
3316 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3317 cmd->transport_state |= CMD_T_ACTIVE;
3318 }
3319 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3320
3321 if (aborted) {
3322 pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d ref_tag: %llu tag: %llu\n",
3323 cmd->se_tmr_req->function,
3324 cmd->se_tmr_req->ref_task_tag, cmd->tag);
3325 target_handle_abort(cmd);
3326 return 0;
3327 }
3328
3329 INIT_WORK(&cmd->work, target_tmr_work);
3330 schedule_work(&cmd->work);
3331 return 0;
3332 }
3333 EXPORT_SYMBOL(transport_generic_handle_tmr);
3334
3335 bool
3336 target_check_wce(struct se_device *dev)
3337 {
3338 bool wce = false;
3339
3340 if (dev->transport->get_write_cache)
3341 wce = dev->transport->get_write_cache(dev);
3342 else if (dev->dev_attrib.emulate_write_cache > 0)
3343 wce = true;
3344
3345 return wce;
3346 }
3347
3348 bool
3349 target_check_fua(struct se_device *dev)
3350 {
3351 return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3352 }
Linux with added FPC-III support