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i40e: define proper net_device::neigh_priv_len
[linux/fpc-iii.git] / drivers / target / target_core_transport.c
blobffa5b9f771b574d6f1aed0b652f0c136d466b041
1 /*******************************************************************************
2 * Filename: target_core_transport.c
3 *
4 * This file contains the Generic Target Engine Core.
5 *
6 * (c) Copyright 2002-2013 Datera, Inc.
7 *
8 * Nicholas A. Bellinger <nab@kernel.org>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 *
24 ******************************************************************************/
25
26 #include <linux/net.h>
27 #include <linux/delay.h>
28 #include <linux/string.h>
29 #include <linux/timer.h>
30 #include <linux/slab.h>
31 #include <linux/spinlock.h>
32 #include <linux/kthread.h>
33 #include <linux/in.h>
34 #include <linux/cdrom.h>
35 #include <linux/module.h>
36 #include <linux/ratelimit.h>
37 #include <linux/vmalloc.h>
38 #include <asm/unaligned.h>
39 #include <net/sock.h>
40 #include <net/tcp.h>
41 #include <scsi/scsi_proto.h>
42 #include <scsi/scsi_common.h>
43
44 #include <target/target_core_base.h>
45 #include <target/target_core_backend.h>
46 #include <target/target_core_fabric.h>
47
48 #include "target_core_internal.h"
49 #include "target_core_alua.h"
50 #include "target_core_pr.h"
51 #include "target_core_ua.h"
52
53 #define CREATE_TRACE_POINTS
54 #include <trace/events/target.h>
55
56 static struct workqueue_struct *target_completion_wq;
57 static struct kmem_cache *se_sess_cache;
58 struct kmem_cache *se_ua_cache;
59 struct kmem_cache *t10_pr_reg_cache;
60 struct kmem_cache *t10_alua_lu_gp_cache;
61 struct kmem_cache *t10_alua_lu_gp_mem_cache;
62 struct kmem_cache *t10_alua_tg_pt_gp_cache;
63 struct kmem_cache *t10_alua_lba_map_cache;
64 struct kmem_cache *t10_alua_lba_map_mem_cache;
65
66 static void transport_complete_task_attr(struct se_cmd *cmd);
67 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason);
68 static void transport_handle_queue_full(struct se_cmd *cmd,
69 struct se_device *dev, int err, bool write_pending);
70 static void target_complete_ok_work(struct work_struct *work);
71
72 int init_se_kmem_caches(void)
73 {
74 se_sess_cache = kmem_cache_create("se_sess_cache",
75 sizeof(struct se_session), __alignof__(struct se_session),
76 0, NULL);
77 if (!se_sess_cache) {
78 pr_err("kmem_cache_create() for struct se_session"
79 " failed\n");
80 goto out;
81 }
82 se_ua_cache = kmem_cache_create("se_ua_cache",
83 sizeof(struct se_ua), __alignof__(struct se_ua),
84 0, NULL);
85 if (!se_ua_cache) {
86 pr_err("kmem_cache_create() for struct se_ua failed\n");
87 goto out_free_sess_cache;
88 }
89 t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
90 sizeof(struct t10_pr_registration),
91 __alignof__(struct t10_pr_registration), 0, NULL);
92 if (!t10_pr_reg_cache) {
93 pr_err("kmem_cache_create() for struct t10_pr_registration"
94 " failed\n");
95 goto out_free_ua_cache;
96 }
97 t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
98 sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
99 0, NULL);
100 if (!t10_alua_lu_gp_cache) {
101 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
102 " failed\n");
103 goto out_free_pr_reg_cache;
104 }
105 t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
106 sizeof(struct t10_alua_lu_gp_member),
107 __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
108 if (!t10_alua_lu_gp_mem_cache) {
109 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
110 "cache failed\n");
111 goto out_free_lu_gp_cache;
112 }
113 t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
114 sizeof(struct t10_alua_tg_pt_gp),
115 __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
116 if (!t10_alua_tg_pt_gp_cache) {
117 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
118 "cache failed\n");
119 goto out_free_lu_gp_mem_cache;
120 }
121 t10_alua_lba_map_cache = kmem_cache_create(
122 "t10_alua_lba_map_cache",
123 sizeof(struct t10_alua_lba_map),
124 __alignof__(struct t10_alua_lba_map), 0, NULL);
125 if (!t10_alua_lba_map_cache) {
126 pr_err("kmem_cache_create() for t10_alua_lba_map_"
127 "cache failed\n");
128 goto out_free_tg_pt_gp_cache;
129 }
130 t10_alua_lba_map_mem_cache = kmem_cache_create(
131 "t10_alua_lba_map_mem_cache",
132 sizeof(struct t10_alua_lba_map_member),
133 __alignof__(struct t10_alua_lba_map_member), 0, NULL);
134 if (!t10_alua_lba_map_mem_cache) {
135 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
136 "cache failed\n");
137 goto out_free_lba_map_cache;
138 }
139
140 target_completion_wq = alloc_workqueue("target_completion",
141 WQ_MEM_RECLAIM, 0);
142 if (!target_completion_wq)
143 goto out_free_lba_map_mem_cache;
144
145 return 0;
146
147 out_free_lba_map_mem_cache:
148 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
149 out_free_lba_map_cache:
150 kmem_cache_destroy(t10_alua_lba_map_cache);
151 out_free_tg_pt_gp_cache:
152 kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
153 out_free_lu_gp_mem_cache:
154 kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
155 out_free_lu_gp_cache:
156 kmem_cache_destroy(t10_alua_lu_gp_cache);
157 out_free_pr_reg_cache:
158 kmem_cache_destroy(t10_pr_reg_cache);
159 out_free_ua_cache:
160 kmem_cache_destroy(se_ua_cache);
161 out_free_sess_cache:
162 kmem_cache_destroy(se_sess_cache);
163 out:
164 return -ENOMEM;
165 }
166
167 void release_se_kmem_caches(void)
168 {
169 destroy_workqueue(target_completion_wq);
170 kmem_cache_destroy(se_sess_cache);
171 kmem_cache_destroy(se_ua_cache);
172 kmem_cache_destroy(t10_pr_reg_cache);
173 kmem_cache_destroy(t10_alua_lu_gp_cache);
174 kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
175 kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
176 kmem_cache_destroy(t10_alua_lba_map_cache);
177 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
178 }
179
180 /* This code ensures unique mib indexes are handed out. */
181 static DEFINE_SPINLOCK(scsi_mib_index_lock);
182 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
183
184 /*
185 * Allocate a new row index for the entry type specified
186 */
187 u32 scsi_get_new_index(scsi_index_t type)
188 {
189 u32 new_index;
190
191 BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
192
193 spin_lock(&scsi_mib_index_lock);
194 new_index = ++scsi_mib_index[type];
195 spin_unlock(&scsi_mib_index_lock);
196
197 return new_index;
198 }
199
200 void transport_subsystem_check_init(void)
201 {
202 int ret;
203 static int sub_api_initialized;
204
205 if (sub_api_initialized)
206 return;
207
208 ret = IS_ENABLED(CONFIG_TCM_IBLOCK) && request_module("target_core_iblock");
209 if (ret != 0)
210 pr_err("Unable to load target_core_iblock\n");
211
212 ret = IS_ENABLED(CONFIG_TCM_FILEIO) && request_module("target_core_file");
213 if (ret != 0)
214 pr_err("Unable to load target_core_file\n");
215
216 ret = IS_ENABLED(CONFIG_TCM_PSCSI) && request_module("target_core_pscsi");
217 if (ret != 0)
218 pr_err("Unable to load target_core_pscsi\n");
219
220 ret = IS_ENABLED(CONFIG_TCM_USER2) && request_module("target_core_user");
221 if (ret != 0)
222 pr_err("Unable to load target_core_user\n");
223
224 sub_api_initialized = 1;
225 }
226
227 static void target_release_sess_cmd_refcnt(struct percpu_ref *ref)
228 {
229 struct se_session *sess = container_of(ref, typeof(*sess), cmd_count);
230
231 wake_up(&sess->cmd_list_wq);
232 }
233
234 /**
235 * transport_init_session - initialize a session object
236 * @se_sess: Session object pointer.
237 *
238 * The caller must have zero-initialized @se_sess before calling this function.
239 */
240 int transport_init_session(struct se_session *se_sess)
241 {
242 INIT_LIST_HEAD(&se_sess->sess_list);
243 INIT_LIST_HEAD(&se_sess->sess_acl_list);
244 INIT_LIST_HEAD(&se_sess->sess_cmd_list);
245 spin_lock_init(&se_sess->sess_cmd_lock);
246 init_waitqueue_head(&se_sess->cmd_list_wq);
247 return percpu_ref_init(&se_sess->cmd_count,
248 target_release_sess_cmd_refcnt, 0, GFP_KERNEL);
249 }
250 EXPORT_SYMBOL(transport_init_session);
251
252 /**
253 * transport_alloc_session - allocate a session object and initialize it
254 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
255 */
256 struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
257 {
258 struct se_session *se_sess;
259 int ret;
260
261 se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
262 if (!se_sess) {
263 pr_err("Unable to allocate struct se_session from"
264 " se_sess_cache\n");
265 return ERR_PTR(-ENOMEM);
266 }
267 ret = transport_init_session(se_sess);
268 if (ret < 0) {
269 kfree(se_sess);
270 return ERR_PTR(ret);
271 }
272 se_sess->sup_prot_ops = sup_prot_ops;
273
274 return se_sess;
275 }
276 EXPORT_SYMBOL(transport_alloc_session);
277
278 /**
279 * transport_alloc_session_tags - allocate target driver private data
280 * @se_sess: Session pointer.
281 * @tag_num: Maximum number of in-flight commands between initiator and target.
282 * @tag_size: Size in bytes of the private data a target driver associates with
283 * each command.
284 */
285 int transport_alloc_session_tags(struct se_session *se_sess,
286 unsigned int tag_num, unsigned int tag_size)
287 {
288 int rc;
289
290 se_sess->sess_cmd_map = kcalloc(tag_size, tag_num,
291 GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
292 if (!se_sess->sess_cmd_map) {
293 se_sess->sess_cmd_map = vzalloc(array_size(tag_size, tag_num));
294 if (!se_sess->sess_cmd_map) {
295 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
296 return -ENOMEM;
297 }
298 }
299
300 rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
301 false, GFP_KERNEL, NUMA_NO_NODE);
302 if (rc < 0) {
303 pr_err("Unable to init se_sess->sess_tag_pool,"
304 " tag_num: %u\n", tag_num);
305 kvfree(se_sess->sess_cmd_map);
306 se_sess->sess_cmd_map = NULL;
307 return -ENOMEM;
308 }
309
310 return 0;
311 }
312 EXPORT_SYMBOL(transport_alloc_session_tags);
313
314 /**
315 * transport_init_session_tags - allocate a session and target driver private data
316 * @tag_num: Maximum number of in-flight commands between initiator and target.
317 * @tag_size: Size in bytes of the private data a target driver associates with
318 * each command.
319 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
320 */
321 static struct se_session *
322 transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
323 enum target_prot_op sup_prot_ops)
324 {
325 struct se_session *se_sess;
326 int rc;
327
328 if (tag_num != 0 && !tag_size) {
329 pr_err("init_session_tags called with percpu-ida tag_num:"
330 " %u, but zero tag_size\n", tag_num);
331 return ERR_PTR(-EINVAL);
332 }
333 if (!tag_num && tag_size) {
334 pr_err("init_session_tags called with percpu-ida tag_size:"
335 " %u, but zero tag_num\n", tag_size);
336 return ERR_PTR(-EINVAL);
337 }
338
339 se_sess = transport_alloc_session(sup_prot_ops);
340 if (IS_ERR(se_sess))
341 return se_sess;
342
343 rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
344 if (rc < 0) {
345 transport_free_session(se_sess);
346 return ERR_PTR(-ENOMEM);
347 }
348
349 return se_sess;
350 }
351
352 /*
353 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
354 */
355 void __transport_register_session(
356 struct se_portal_group *se_tpg,
357 struct se_node_acl *se_nacl,
358 struct se_session *se_sess,
359 void *fabric_sess_ptr)
360 {
361 const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
362 unsigned char buf[PR_REG_ISID_LEN];
363 unsigned long flags;
364
365 se_sess->se_tpg = se_tpg;
366 se_sess->fabric_sess_ptr = fabric_sess_ptr;
367 /*
368 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
369 *
370 * Only set for struct se_session's that will actually be moving I/O.
371 * eg: *NOT* discovery sessions.
372 */
373 if (se_nacl) {
374 /*
375 *
376 * Determine if fabric allows for T10-PI feature bits exposed to
377 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
378 *
379 * If so, then always save prot_type on a per se_node_acl node
380 * basis and re-instate the previous sess_prot_type to avoid
381 * disabling PI from below any previously initiator side
382 * registered LUNs.
383 */
384 if (se_nacl->saved_prot_type)
385 se_sess->sess_prot_type = se_nacl->saved_prot_type;
386 else if (tfo->tpg_check_prot_fabric_only)
387 se_sess->sess_prot_type = se_nacl->saved_prot_type =
388 tfo->tpg_check_prot_fabric_only(se_tpg);
389 /*
390 * If the fabric module supports an ISID based TransportID,
391 * save this value in binary from the fabric I_T Nexus now.
392 */
393 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
394 memset(&buf[0], 0, PR_REG_ISID_LEN);
395 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
396 &buf[0], PR_REG_ISID_LEN);
397 se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
398 }
399
400 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
401 /*
402 * The se_nacl->nacl_sess pointer will be set to the
403 * last active I_T Nexus for each struct se_node_acl.
404 */
405 se_nacl->nacl_sess = se_sess;
406
407 list_add_tail(&se_sess->sess_acl_list,
408 &se_nacl->acl_sess_list);
409 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
410 }
411 list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
412
413 pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
414 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
415 }
416 EXPORT_SYMBOL(__transport_register_session);
417
418 void transport_register_session(
419 struct se_portal_group *se_tpg,
420 struct se_node_acl *se_nacl,
421 struct se_session *se_sess,
422 void *fabric_sess_ptr)
423 {
424 unsigned long flags;
425
426 spin_lock_irqsave(&se_tpg->session_lock, flags);
427 __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
428 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
429 }
430 EXPORT_SYMBOL(transport_register_session);
431
432 struct se_session *
433 target_setup_session(struct se_portal_group *tpg,
434 unsigned int tag_num, unsigned int tag_size,
435 enum target_prot_op prot_op,
436 const char *initiatorname, void *private,
437 int (*callback)(struct se_portal_group *,
438 struct se_session *, void *))
439 {
440 struct se_session *sess;
441
442 /*
443 * If the fabric driver is using percpu-ida based pre allocation
444 * of I/O descriptor tags, go ahead and perform that setup now..
445 */
446 if (tag_num != 0)
447 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
448 else
449 sess = transport_alloc_session(prot_op);
450
451 if (IS_ERR(sess))
452 return sess;
453
454 sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
455 (unsigned char *)initiatorname);
456 if (!sess->se_node_acl) {
457 transport_free_session(sess);
458 return ERR_PTR(-EACCES);
459 }
460 /*
461 * Go ahead and perform any remaining fabric setup that is
462 * required before transport_register_session().
463 */
464 if (callback != NULL) {
465 int rc = callback(tpg, sess, private);
466 if (rc) {
467 transport_free_session(sess);
468 return ERR_PTR(rc);
469 }
470 }
471
472 transport_register_session(tpg, sess->se_node_acl, sess, private);
473 return sess;
474 }
475 EXPORT_SYMBOL(target_setup_session);
476
477 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
478 {
479 struct se_session *se_sess;
480 ssize_t len = 0;
481
482 spin_lock_bh(&se_tpg->session_lock);
483 list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
484 if (!se_sess->se_node_acl)
485 continue;
486 if (!se_sess->se_node_acl->dynamic_node_acl)
487 continue;
488 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
489 break;
490
491 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
492 se_sess->se_node_acl->initiatorname);
493 len += 1; /* Include NULL terminator */
494 }
495 spin_unlock_bh(&se_tpg->session_lock);
496
497 return len;
498 }
499 EXPORT_SYMBOL(target_show_dynamic_sessions);
500
501 static void target_complete_nacl(struct kref *kref)
502 {
503 struct se_node_acl *nacl = container_of(kref,
504 struct se_node_acl, acl_kref);
505 struct se_portal_group *se_tpg = nacl->se_tpg;
506
507 if (!nacl->dynamic_stop) {
508 complete(&nacl->acl_free_comp);
509 return;
510 }
511
512 mutex_lock(&se_tpg->acl_node_mutex);
513 list_del_init(&nacl->acl_list);
514 mutex_unlock(&se_tpg->acl_node_mutex);
515
516 core_tpg_wait_for_nacl_pr_ref(nacl);
517 core_free_device_list_for_node(nacl, se_tpg);
518 kfree(nacl);
519 }
520
521 void target_put_nacl(struct se_node_acl *nacl)
522 {
523 kref_put(&nacl->acl_kref, target_complete_nacl);
524 }
525 EXPORT_SYMBOL(target_put_nacl);
526
527 void transport_deregister_session_configfs(struct se_session *se_sess)
528 {
529 struct se_node_acl *se_nacl;
530 unsigned long flags;
531 /*
532 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
533 */
534 se_nacl = se_sess->se_node_acl;
535 if (se_nacl) {
536 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
537 if (!list_empty(&se_sess->sess_acl_list))
538 list_del_init(&se_sess->sess_acl_list);
539 /*
540 * If the session list is empty, then clear the pointer.
541 * Otherwise, set the struct se_session pointer from the tail
542 * element of the per struct se_node_acl active session list.
543 */
544 if (list_empty(&se_nacl->acl_sess_list))
545 se_nacl->nacl_sess = NULL;
546 else {
547 se_nacl->nacl_sess = container_of(
548 se_nacl->acl_sess_list.prev,
549 struct se_session, sess_acl_list);
550 }
551 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
552 }
553 }
554 EXPORT_SYMBOL(transport_deregister_session_configfs);
555
556 void transport_free_session(struct se_session *se_sess)
557 {
558 struct se_node_acl *se_nacl = se_sess->se_node_acl;
559
560 /*
561 * Drop the se_node_acl->nacl_kref obtained from within
562 * core_tpg_get_initiator_node_acl().
563 */
564 if (se_nacl) {
565 struct se_portal_group *se_tpg = se_nacl->se_tpg;
566 const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
567 unsigned long flags;
568
569 se_sess->se_node_acl = NULL;
570
571 /*
572 * Also determine if we need to drop the extra ->cmd_kref if
573 * it had been previously dynamically generated, and
574 * the endpoint is not caching dynamic ACLs.
575 */
576 mutex_lock(&se_tpg->acl_node_mutex);
577 if (se_nacl->dynamic_node_acl &&
578 !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
579 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
580 if (list_empty(&se_nacl->acl_sess_list))
581 se_nacl->dynamic_stop = true;
582 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
583
584 if (se_nacl->dynamic_stop)
585 list_del_init(&se_nacl->acl_list);
586 }
587 mutex_unlock(&se_tpg->acl_node_mutex);
588
589 if (se_nacl->dynamic_stop)
590 target_put_nacl(se_nacl);
591
592 target_put_nacl(se_nacl);
593 }
594 if (se_sess->sess_cmd_map) {
595 sbitmap_queue_free(&se_sess->sess_tag_pool);
596 kvfree(se_sess->sess_cmd_map);
597 }
598 percpu_ref_exit(&se_sess->cmd_count);
599 kmem_cache_free(se_sess_cache, se_sess);
600 }
601 EXPORT_SYMBOL(transport_free_session);
602
603 void transport_deregister_session(struct se_session *se_sess)
604 {
605 struct se_portal_group *se_tpg = se_sess->se_tpg;
606 unsigned long flags;
607
608 if (!se_tpg) {
609 transport_free_session(se_sess);
610 return;
611 }
612
613 spin_lock_irqsave(&se_tpg->session_lock, flags);
614 list_del(&se_sess->sess_list);
615 se_sess->se_tpg = NULL;
616 se_sess->fabric_sess_ptr = NULL;
617 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
618
619 pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
620 se_tpg->se_tpg_tfo->get_fabric_name());
621 /*
622 * If last kref is dropping now for an explicit NodeACL, awake sleeping
623 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
624 * removal context from within transport_free_session() code.
625 *
626 * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
627 * to release all remaining generate_node_acl=1 created ACL resources.
628 */
629
630 transport_free_session(se_sess);
631 }
632 EXPORT_SYMBOL(transport_deregister_session);
633
634 void target_remove_session(struct se_session *se_sess)
635 {
636 transport_deregister_session_configfs(se_sess);
637 transport_deregister_session(se_sess);
638 }
639 EXPORT_SYMBOL(target_remove_session);
640
641 static void target_remove_from_state_list(struct se_cmd *cmd)
642 {
643 struct se_device *dev = cmd->se_dev;
644 unsigned long flags;
645
646 if (!dev)
647 return;
648
649 spin_lock_irqsave(&dev->execute_task_lock, flags);
650 if (cmd->state_active) {
651 list_del(&cmd->state_list);
652 cmd->state_active = false;
653 }
654 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
655 }
656
657 /*
658 * This function is called by the target core after the target core has
659 * finished processing a SCSI command or SCSI TMF. Both the regular command
660 * processing code and the code for aborting commands can call this
661 * function. CMD_T_STOP is set if and only if another thread is waiting
662 * inside transport_wait_for_tasks() for t_transport_stop_comp.
663 */
664 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
665 {
666 unsigned long flags;
667
668 target_remove_from_state_list(cmd);
669
670 /*
671 * Clear struct se_cmd->se_lun before the handoff to FE.
672 */
673 cmd->se_lun = NULL;
674
675 spin_lock_irqsave(&cmd->t_state_lock, flags);
676 /*
677 * Determine if frontend context caller is requesting the stopping of
678 * this command for frontend exceptions.
679 */
680 if (cmd->transport_state & CMD_T_STOP) {
681 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
682 __func__, __LINE__, cmd->tag);
683
684 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
685
686 complete_all(&cmd->t_transport_stop_comp);
687 return 1;
688 }
689 cmd->transport_state &= ~CMD_T_ACTIVE;
690 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
691
692 /*
693 * Some fabric modules like tcm_loop can release their internally
694 * allocated I/O reference and struct se_cmd now.
695 *
696 * Fabric modules are expected to return '1' here if the se_cmd being
697 * passed is released at this point, or zero if not being released.
698 */
699 return cmd->se_tfo->check_stop_free(cmd);
700 }
701
702 static void transport_lun_remove_cmd(struct se_cmd *cmd)
703 {
704 struct se_lun *lun = cmd->se_lun;
705
706 if (!lun)
707 return;
708
709 if (cmpxchg(&cmd->lun_ref_active, true, false))
710 percpu_ref_put(&lun->lun_ref);
711 }
712
713 int transport_cmd_finish_abort(struct se_cmd *cmd)
714 {
715 bool send_tas = cmd->transport_state & CMD_T_TAS;
716 bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF);
717 int ret = 0;
718
719 if (send_tas)
720 transport_send_task_abort(cmd);
721
722 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
723 transport_lun_remove_cmd(cmd);
724 /*
725 * Allow the fabric driver to unmap any resources before
726 * releasing the descriptor via TFO->release_cmd()
727 */
728 if (!send_tas)
729 cmd->se_tfo->aborted_task(cmd);
730
731 if (transport_cmd_check_stop_to_fabric(cmd))
732 return 1;
733 if (!send_tas && ack_kref)
734 ret = target_put_sess_cmd(cmd);
735
736 return ret;
737 }
738
739 static void target_complete_failure_work(struct work_struct *work)
740 {
741 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
742
743 transport_generic_request_failure(cmd,
744 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
745 }
746
747 /*
748 * Used when asking transport to copy Sense Data from the underlying
749 * Linux/SCSI struct scsi_cmnd
750 */
751 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
752 {
753 struct se_device *dev = cmd->se_dev;
754
755 WARN_ON(!cmd->se_lun);
756
757 if (!dev)
758 return NULL;
759
760 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
761 return NULL;
762
763 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
764
765 pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
766 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
767 return cmd->sense_buffer;
768 }
769
770 void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
771 {
772 unsigned char *cmd_sense_buf;
773 unsigned long flags;
774
775 spin_lock_irqsave(&cmd->t_state_lock, flags);
776 cmd_sense_buf = transport_get_sense_buffer(cmd);
777 if (!cmd_sense_buf) {
778 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
779 return;
780 }
781
782 cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
783 memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
784 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
785 }
786 EXPORT_SYMBOL(transport_copy_sense_to_cmd);
787
788 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
789 {
790 struct se_device *dev = cmd->se_dev;
791 int success;
792 unsigned long flags;
793
794 cmd->scsi_status = scsi_status;
795
796 spin_lock_irqsave(&cmd->t_state_lock, flags);
797 switch (cmd->scsi_status) {
798 case SAM_STAT_CHECK_CONDITION:
799 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
800 success = 1;
801 else
802 success = 0;
803 break;
804 default:
805 success = 1;
806 break;
807 }
808
809 /*
810 * Check for case where an explicit ABORT_TASK has been received
811 * and transport_wait_for_tasks() will be waiting for completion..
812 */
813 if (cmd->transport_state & CMD_T_ABORTED ||
814 cmd->transport_state & CMD_T_STOP) {
815 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
816 /*
817 * If COMPARE_AND_WRITE was stopped by __transport_wait_for_tasks(),
818 * release se_device->caw_sem obtained by sbc_compare_and_write()
819 * since target_complete_ok_work() or target_complete_failure_work()
820 * won't be called to invoke the normal CAW completion callbacks.
821 */
822 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
823 up(&dev->caw_sem);
824 }
825 complete_all(&cmd->t_transport_stop_comp);
826 return;
827 } else if (!success) {
828 INIT_WORK(&cmd->work, target_complete_failure_work);
829 } else {
830 INIT_WORK(&cmd->work, target_complete_ok_work);
831 }
832
833 cmd->t_state = TRANSPORT_COMPLETE;
834 cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
835 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
836
837 if (cmd->se_cmd_flags & SCF_USE_CPUID)
838 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
839 else
840 queue_work(target_completion_wq, &cmd->work);
841 }
842 EXPORT_SYMBOL(target_complete_cmd);
843
844 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
845 {
846 if ((scsi_status == SAM_STAT_GOOD ||
847 cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
848 length < cmd->data_length) {
849 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
850 cmd->residual_count += cmd->data_length - length;
851 } else {
852 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
853 cmd->residual_count = cmd->data_length - length;
854 }
855
856 cmd->data_length = length;
857 }
858
859 target_complete_cmd(cmd, scsi_status);
860 }
861 EXPORT_SYMBOL(target_complete_cmd_with_length);
862
863 static void target_add_to_state_list(struct se_cmd *cmd)
864 {
865 struct se_device *dev = cmd->se_dev;
866 unsigned long flags;
867
868 spin_lock_irqsave(&dev->execute_task_lock, flags);
869 if (!cmd->state_active) {
870 list_add_tail(&cmd->state_list, &dev->state_list);
871 cmd->state_active = true;
872 }
873 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
874 }
875
876 /*
877 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
878 */
879 static void transport_write_pending_qf(struct se_cmd *cmd);
880 static void transport_complete_qf(struct se_cmd *cmd);
881
882 void target_qf_do_work(struct work_struct *work)
883 {
884 struct se_device *dev = container_of(work, struct se_device,
885 qf_work_queue);
886 LIST_HEAD(qf_cmd_list);
887 struct se_cmd *cmd, *cmd_tmp;
888
889 spin_lock_irq(&dev->qf_cmd_lock);
890 list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
891 spin_unlock_irq(&dev->qf_cmd_lock);
892
893 list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
894 list_del(&cmd->se_qf_node);
895 atomic_dec_mb(&dev->dev_qf_count);
896
897 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
898 " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
899 (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
900 (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
901 : "UNKNOWN");
902
903 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
904 transport_write_pending_qf(cmd);
905 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
906 cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
907 transport_complete_qf(cmd);
908 }
909 }
910
911 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
912 {
913 switch (cmd->data_direction) {
914 case DMA_NONE:
915 return "NONE";
916 case DMA_FROM_DEVICE:
917 return "READ";
918 case DMA_TO_DEVICE:
919 return "WRITE";
920 case DMA_BIDIRECTIONAL:
921 return "BIDI";
922 default:
923 break;
924 }
925
926 return "UNKNOWN";
927 }
928
929 void transport_dump_dev_state(
930 struct se_device *dev,
931 char *b,
932 int *bl)
933 {
934 *bl += sprintf(b + *bl, "Status: ");
935 if (dev->export_count)
936 *bl += sprintf(b + *bl, "ACTIVATED");
937 else
938 *bl += sprintf(b + *bl, "DEACTIVATED");
939
940 *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
941 *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
942 dev->dev_attrib.block_size,
943 dev->dev_attrib.hw_max_sectors);
944 *bl += sprintf(b + *bl, " ");
945 }
946
947 void transport_dump_vpd_proto_id(
948 struct t10_vpd *vpd,
949 unsigned char *p_buf,
950 int p_buf_len)
951 {
952 unsigned char buf[VPD_TMP_BUF_SIZE];
953 int len;
954
955 memset(buf, 0, VPD_TMP_BUF_SIZE);
956 len = sprintf(buf, "T10 VPD Protocol Identifier: ");
957
958 switch (vpd->protocol_identifier) {
959 case 0x00:
960 sprintf(buf+len, "Fibre Channel\n");
961 break;
962 case 0x10:
963 sprintf(buf+len, "Parallel SCSI\n");
964 break;
965 case 0x20:
966 sprintf(buf+len, "SSA\n");
967 break;
968 case 0x30:
969 sprintf(buf+len, "IEEE 1394\n");
970 break;
971 case 0x40:
972 sprintf(buf+len, "SCSI Remote Direct Memory Access"
973 " Protocol\n");
974 break;
975 case 0x50:
976 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
977 break;
978 case 0x60:
979 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
980 break;
981 case 0x70:
982 sprintf(buf+len, "Automation/Drive Interface Transport"
983 " Protocol\n");
984 break;
985 case 0x80:
986 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
987 break;
988 default:
989 sprintf(buf+len, "Unknown 0x%02x\n",
990 vpd->protocol_identifier);
991 break;
992 }
993
994 if (p_buf)
995 strncpy(p_buf, buf, p_buf_len);
996 else
997 pr_debug("%s", buf);
998 }
999
1000 void
1001 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1002 {
1003 /*
1004 * Check if the Protocol Identifier Valid (PIV) bit is set..
1005 *
1006 * from spc3r23.pdf section 7.5.1
1007 */
1008 if (page_83[1] & 0x80) {
1009 vpd->protocol_identifier = (page_83[0] & 0xf0);
1010 vpd->protocol_identifier_set = 1;
1011 transport_dump_vpd_proto_id(vpd, NULL, 0);
1012 }
1013 }
1014 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1015
1016 int transport_dump_vpd_assoc(
1017 struct t10_vpd *vpd,
1018 unsigned char *p_buf,
1019 int p_buf_len)
1020 {
1021 unsigned char buf[VPD_TMP_BUF_SIZE];
1022 int ret = 0;
1023 int len;
1024
1025 memset(buf, 0, VPD_TMP_BUF_SIZE);
1026 len = sprintf(buf, "T10 VPD Identifier Association: ");
1027
1028 switch (vpd->association) {
1029 case 0x00:
1030 sprintf(buf+len, "addressed logical unit\n");
1031 break;
1032 case 0x10:
1033 sprintf(buf+len, "target port\n");
1034 break;
1035 case 0x20:
1036 sprintf(buf+len, "SCSI target device\n");
1037 break;
1038 default:
1039 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1040 ret = -EINVAL;
1041 break;
1042 }
1043
1044 if (p_buf)
1045 strncpy(p_buf, buf, p_buf_len);
1046 else
1047 pr_debug("%s", buf);
1048
1049 return ret;
1050 }
1051
1052 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1053 {
1054 /*
1055 * The VPD identification association..
1056 *
1057 * from spc3r23.pdf Section 7.6.3.1 Table 297
1058 */
1059 vpd->association = (page_83[1] & 0x30);
1060 return transport_dump_vpd_assoc(vpd, NULL, 0);
1061 }
1062 EXPORT_SYMBOL(transport_set_vpd_assoc);
1063
1064 int transport_dump_vpd_ident_type(
1065 struct t10_vpd *vpd,
1066 unsigned char *p_buf,
1067 int p_buf_len)
1068 {
1069 unsigned char buf[VPD_TMP_BUF_SIZE];
1070 int ret = 0;
1071 int len;
1072
1073 memset(buf, 0, VPD_TMP_BUF_SIZE);
1074 len = sprintf(buf, "T10 VPD Identifier Type: ");
1075
1076 switch (vpd->device_identifier_type) {
1077 case 0x00:
1078 sprintf(buf+len, "Vendor specific\n");
1079 break;
1080 case 0x01:
1081 sprintf(buf+len, "T10 Vendor ID based\n");
1082 break;
1083 case 0x02:
1084 sprintf(buf+len, "EUI-64 based\n");
1085 break;
1086 case 0x03:
1087 sprintf(buf+len, "NAA\n");
1088 break;
1089 case 0x04:
1090 sprintf(buf+len, "Relative target port identifier\n");
1091 break;
1092 case 0x08:
1093 sprintf(buf+len, "SCSI name string\n");
1094 break;
1095 default:
1096 sprintf(buf+len, "Unsupported: 0x%02x\n",
1097 vpd->device_identifier_type);
1098 ret = -EINVAL;
1099 break;
1100 }
1101
1102 if (p_buf) {
1103 if (p_buf_len < strlen(buf)+1)
1104 return -EINVAL;
1105 strncpy(p_buf, buf, p_buf_len);
1106 } else {
1107 pr_debug("%s", buf);
1108 }
1109
1110 return ret;
1111 }
1112
1113 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1114 {
1115 /*
1116 * The VPD identifier type..
1117 *
1118 * from spc3r23.pdf Section 7.6.3.1 Table 298
1119 */
1120 vpd->device_identifier_type = (page_83[1] & 0x0f);
1121 return transport_dump_vpd_ident_type(vpd, NULL, 0);
1122 }
1123 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1124
1125 int transport_dump_vpd_ident(
1126 struct t10_vpd *vpd,
1127 unsigned char *p_buf,
1128 int p_buf_len)
1129 {
1130 unsigned char buf[VPD_TMP_BUF_SIZE];
1131 int ret = 0;
1132
1133 memset(buf, 0, VPD_TMP_BUF_SIZE);
1134
1135 switch (vpd->device_identifier_code_set) {
1136 case 0x01: /* Binary */
1137 snprintf(buf, sizeof(buf),
1138 "T10 VPD Binary Device Identifier: %s\n",
1139 &vpd->device_identifier[0]);
1140 break;
1141 case 0x02: /* ASCII */
1142 snprintf(buf, sizeof(buf),
1143 "T10 VPD ASCII Device Identifier: %s\n",
1144 &vpd->device_identifier[0]);
1145 break;
1146 case 0x03: /* UTF-8 */
1147 snprintf(buf, sizeof(buf),
1148 "T10 VPD UTF-8 Device Identifier: %s\n",
1149 &vpd->device_identifier[0]);
1150 break;
1151 default:
1152 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1153 " 0x%02x", vpd->device_identifier_code_set);
1154 ret = -EINVAL;
1155 break;
1156 }
1157
1158 if (p_buf)
1159 strncpy(p_buf, buf, p_buf_len);
1160 else
1161 pr_debug("%s", buf);
1162
1163 return ret;
1164 }
1165
1166 int
1167 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1168 {
1169 static const char hex_str[] = "0123456789abcdef";
1170 int j = 0, i = 4; /* offset to start of the identifier */
1171
1172 /*
1173 * The VPD Code Set (encoding)
1174 *
1175 * from spc3r23.pdf Section 7.6.3.1 Table 296
1176 */
1177 vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1178 switch (vpd->device_identifier_code_set) {
1179 case 0x01: /* Binary */
1180 vpd->device_identifier[j++] =
1181 hex_str[vpd->device_identifier_type];
1182 while (i < (4 + page_83[3])) {
1183 vpd->device_identifier[j++] =
1184 hex_str[(page_83[i] & 0xf0) >> 4];
1185 vpd->device_identifier[j++] =
1186 hex_str[page_83[i] & 0x0f];
1187 i++;
1188 }
1189 break;
1190 case 0x02: /* ASCII */
1191 case 0x03: /* UTF-8 */
1192 while (i < (4 + page_83[3]))
1193 vpd->device_identifier[j++] = page_83[i++];
1194 break;
1195 default:
1196 break;
1197 }
1198
1199 return transport_dump_vpd_ident(vpd, NULL, 0);
1200 }
1201 EXPORT_SYMBOL(transport_set_vpd_ident);
1202
1203 static sense_reason_t
1204 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1205 unsigned int size)
1206 {
1207 u32 mtl;
1208
1209 if (!cmd->se_tfo->max_data_sg_nents)
1210 return TCM_NO_SENSE;
1211 /*
1212 * Check if fabric enforced maximum SGL entries per I/O descriptor
1213 * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT +
1214 * residual_count and reduce original cmd->data_length to maximum
1215 * length based on single PAGE_SIZE entry scatter-lists.
1216 */
1217 mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1218 if (cmd->data_length > mtl) {
1219 /*
1220 * If an existing CDB overflow is present, calculate new residual
1221 * based on CDB size minus fabric maximum transfer length.
1222 *
1223 * If an existing CDB underflow is present, calculate new residual
1224 * based on original cmd->data_length minus fabric maximum transfer
1225 * length.
1226 *
1227 * Otherwise, set the underflow residual based on cmd->data_length
1228 * minus fabric maximum transfer length.
1229 */
1230 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1231 cmd->residual_count = (size - mtl);
1232 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1233 u32 orig_dl = size + cmd->residual_count;
1234 cmd->residual_count = (orig_dl - mtl);
1235 } else {
1236 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1237 cmd->residual_count = (cmd->data_length - mtl);
1238 }
1239 cmd->data_length = mtl;
1240 /*
1241 * Reset sbc_check_prot() calculated protection payload
1242 * length based upon the new smaller MTL.
1243 */
1244 if (cmd->prot_length) {
1245 u32 sectors = (mtl / dev->dev_attrib.block_size);
1246 cmd->prot_length = dev->prot_length * sectors;
1247 }
1248 }
1249 return TCM_NO_SENSE;
1250 }
1251
1252 sense_reason_t
1253 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1254 {
1255 struct se_device *dev = cmd->se_dev;
1256
1257 if (cmd->unknown_data_length) {
1258 cmd->data_length = size;
1259 } else if (size != cmd->data_length) {
1260 pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1261 " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1262 " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1263 cmd->data_length, size, cmd->t_task_cdb[0]);
1264
1265 if (cmd->data_direction == DMA_TO_DEVICE) {
1266 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1267 pr_err_ratelimited("Rejecting underflow/overflow"
1268 " for WRITE data CDB\n");
1269 return TCM_INVALID_CDB_FIELD;
1270 }
1271 /*
1272 * Some fabric drivers like iscsi-target still expect to
1273 * always reject overflow writes. Reject this case until
1274 * full fabric driver level support for overflow writes
1275 * is introduced tree-wide.
1276 */
1277 if (size > cmd->data_length) {
1278 pr_err_ratelimited("Rejecting overflow for"
1279 " WRITE control CDB\n");
1280 return TCM_INVALID_CDB_FIELD;
1281 }
1282 }
1283 /*
1284 * Reject READ_* or WRITE_* with overflow/underflow for
1285 * type SCF_SCSI_DATA_CDB.
1286 */
1287 if (dev->dev_attrib.block_size != 512) {
1288 pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1289 " CDB on non 512-byte sector setup subsystem"
1290 " plugin: %s\n", dev->transport->name);
1291 /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1292 return TCM_INVALID_CDB_FIELD;
1293 }
1294 /*
1295 * For the overflow case keep the existing fabric provided
1296 * ->data_length. Otherwise for the underflow case, reset
1297 * ->data_length to the smaller SCSI expected data transfer
1298 * length.
1299 */
1300 if (size > cmd->data_length) {
1301 cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1302 cmd->residual_count = (size - cmd->data_length);
1303 } else {
1304 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1305 cmd->residual_count = (cmd->data_length - size);
1306 cmd->data_length = size;
1307 }
1308 }
1309
1310 return target_check_max_data_sg_nents(cmd, dev, size);
1311
1312 }
1313
1314 /*
1315 * Used by fabric modules containing a local struct se_cmd within their
1316 * fabric dependent per I/O descriptor.
1317 *
1318 * Preserves the value of @cmd->tag.
1319 */
1320 void transport_init_se_cmd(
1321 struct se_cmd *cmd,
1322 const struct target_core_fabric_ops *tfo,
1323 struct se_session *se_sess,
1324 u32 data_length,
1325 int data_direction,
1326 int task_attr,
1327 unsigned char *sense_buffer)
1328 {
1329 INIT_LIST_HEAD(&cmd->se_delayed_node);
1330 INIT_LIST_HEAD(&cmd->se_qf_node);
1331 INIT_LIST_HEAD(&cmd->se_cmd_list);
1332 INIT_LIST_HEAD(&cmd->state_list);
1333 init_completion(&cmd->t_transport_stop_comp);
1334 cmd->compl = NULL;
1335 spin_lock_init(&cmd->t_state_lock);
1336 INIT_WORK(&cmd->work, NULL);
1337 kref_init(&cmd->cmd_kref);
1338
1339 cmd->se_tfo = tfo;
1340 cmd->se_sess = se_sess;
1341 cmd->data_length = data_length;
1342 cmd->data_direction = data_direction;
1343 cmd->sam_task_attr = task_attr;
1344 cmd->sense_buffer = sense_buffer;
1345
1346 cmd->state_active = false;
1347 }
1348 EXPORT_SYMBOL(transport_init_se_cmd);
1349
1350 static sense_reason_t
1351 transport_check_alloc_task_attr(struct se_cmd *cmd)
1352 {
1353 struct se_device *dev = cmd->se_dev;
1354
1355 /*
1356 * Check if SAM Task Attribute emulation is enabled for this
1357 * struct se_device storage object
1358 */
1359 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1360 return 0;
1361
1362 if (cmd->sam_task_attr == TCM_ACA_TAG) {
1363 pr_debug("SAM Task Attribute ACA"
1364 " emulation is not supported\n");
1365 return TCM_INVALID_CDB_FIELD;
1366 }
1367
1368 return 0;
1369 }
1370
1371 sense_reason_t
1372 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1373 {
1374 struct se_device *dev = cmd->se_dev;
1375 sense_reason_t ret;
1376
1377 /*
1378 * Ensure that the received CDB is less than the max (252 + 8) bytes
1379 * for VARIABLE_LENGTH_CMD
1380 */
1381 if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1382 pr_err("Received SCSI CDB with command_size: %d that"
1383 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1384 scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1385 return TCM_INVALID_CDB_FIELD;
1386 }
1387 /*
1388 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1389 * allocate the additional extended CDB buffer now.. Otherwise
1390 * setup the pointer from __t_task_cdb to t_task_cdb.
1391 */
1392 if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1393 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1394 GFP_KERNEL);
1395 if (!cmd->t_task_cdb) {
1396 pr_err("Unable to allocate cmd->t_task_cdb"
1397 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1398 scsi_command_size(cdb),
1399 (unsigned long)sizeof(cmd->__t_task_cdb));
1400 return TCM_OUT_OF_RESOURCES;
1401 }
1402 } else
1403 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1404 /*
1405 * Copy the original CDB into cmd->
1406 */
1407 memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1408
1409 trace_target_sequencer_start(cmd);
1410
1411 ret = dev->transport->parse_cdb(cmd);
1412 if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1413 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1414 cmd->se_tfo->get_fabric_name(),
1415 cmd->se_sess->se_node_acl->initiatorname,
1416 cmd->t_task_cdb[0]);
1417 if (ret)
1418 return ret;
1419
1420 ret = transport_check_alloc_task_attr(cmd);
1421 if (ret)
1422 return ret;
1423
1424 cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1425 atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1426 return 0;
1427 }
1428 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1429
1430 /*
1431 * Used by fabric module frontends to queue tasks directly.
1432 * May only be used from process context.
1433 */
1434 int transport_handle_cdb_direct(
1435 struct se_cmd *cmd)
1436 {
1437 sense_reason_t ret;
1438
1439 if (!cmd->se_lun) {
1440 dump_stack();
1441 pr_err("cmd->se_lun is NULL\n");
1442 return -EINVAL;
1443 }
1444 if (in_interrupt()) {
1445 dump_stack();
1446 pr_err("transport_generic_handle_cdb cannot be called"
1447 " from interrupt context\n");
1448 return -EINVAL;
1449 }
1450 /*
1451 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1452 * outstanding descriptors are handled correctly during shutdown via
1453 * transport_wait_for_tasks()
1454 *
1455 * Also, we don't take cmd->t_state_lock here as we only expect
1456 * this to be called for initial descriptor submission.
1457 */
1458 cmd->t_state = TRANSPORT_NEW_CMD;
1459 cmd->transport_state |= CMD_T_ACTIVE;
1460
1461 /*
1462 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1463 * so follow TRANSPORT_NEW_CMD processing thread context usage
1464 * and call transport_generic_request_failure() if necessary..
1465 */
1466 ret = transport_generic_new_cmd(cmd);
1467 if (ret)
1468 transport_generic_request_failure(cmd, ret);
1469 return 0;
1470 }
1471 EXPORT_SYMBOL(transport_handle_cdb_direct);
1472
1473 sense_reason_t
1474 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1475 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1476 {
1477 if (!sgl || !sgl_count)
1478 return 0;
1479
1480 /*
1481 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1482 * scatterlists already have been set to follow what the fabric
1483 * passes for the original expected data transfer length.
1484 */
1485 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1486 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1487 " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1488 return TCM_INVALID_CDB_FIELD;
1489 }
1490
1491 cmd->t_data_sg = sgl;
1492 cmd->t_data_nents = sgl_count;
1493 cmd->t_bidi_data_sg = sgl_bidi;
1494 cmd->t_bidi_data_nents = sgl_bidi_count;
1495
1496 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1497 return 0;
1498 }
1499
1500 /**
1501 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1502 * se_cmd + use pre-allocated SGL memory.
1503 *
1504 * @se_cmd: command descriptor to submit
1505 * @se_sess: associated se_sess for endpoint
1506 * @cdb: pointer to SCSI CDB
1507 * @sense: pointer to SCSI sense buffer
1508 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1509 * @data_length: fabric expected data transfer length
1510 * @task_attr: SAM task attribute
1511 * @data_dir: DMA data direction
1512 * @flags: flags for command submission from target_sc_flags_tables
1513 * @sgl: struct scatterlist memory for unidirectional mapping
1514 * @sgl_count: scatterlist count for unidirectional mapping
1515 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1516 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1517 * @sgl_prot: struct scatterlist memory protection information
1518 * @sgl_prot_count: scatterlist count for protection information
1519 *
1520 * Task tags are supported if the caller has set @se_cmd->tag.
1521 *
1522 * Returns non zero to signal active I/O shutdown failure. All other
1523 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1524 * but still return zero here.
1525 *
1526 * This may only be called from process context, and also currently
1527 * assumes internal allocation of fabric payload buffer by target-core.
1528 */
1529 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1530 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1531 u32 data_length, int task_attr, int data_dir, int flags,
1532 struct scatterlist *sgl, u32 sgl_count,
1533 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1534 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1535 {
1536 struct se_portal_group *se_tpg;
1537 sense_reason_t rc;
1538 int ret;
1539
1540 se_tpg = se_sess->se_tpg;
1541 BUG_ON(!se_tpg);
1542 BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1543 BUG_ON(in_interrupt());
1544 /*
1545 * Initialize se_cmd for target operation. From this point
1546 * exceptions are handled by sending exception status via
1547 * target_core_fabric_ops->queue_status() callback
1548 */
1549 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1550 data_length, data_dir, task_attr, sense);
1551
1552 if (flags & TARGET_SCF_USE_CPUID)
1553 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1554 else
1555 se_cmd->cpuid = WORK_CPU_UNBOUND;
1556
1557 if (flags & TARGET_SCF_UNKNOWN_SIZE)
1558 se_cmd->unknown_data_length = 1;
1559 /*
1560 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1561 * se_sess->sess_cmd_list. A second kref_get here is necessary
1562 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1563 * kref_put() to happen during fabric packet acknowledgement.
1564 */
1565 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1566 if (ret)
1567 return ret;
1568 /*
1569 * Signal bidirectional data payloads to target-core
1570 */
1571 if (flags & TARGET_SCF_BIDI_OP)
1572 se_cmd->se_cmd_flags |= SCF_BIDI;
1573 /*
1574 * Locate se_lun pointer and attach it to struct se_cmd
1575 */
1576 rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1577 if (rc) {
1578 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1579 target_put_sess_cmd(se_cmd);
1580 return 0;
1581 }
1582
1583 rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1584 if (rc != 0) {
1585 transport_generic_request_failure(se_cmd, rc);
1586 return 0;
1587 }
1588
1589 /*
1590 * Save pointers for SGLs containing protection information,
1591 * if present.
1592 */
1593 if (sgl_prot_count) {
1594 se_cmd->t_prot_sg = sgl_prot;
1595 se_cmd->t_prot_nents = sgl_prot_count;
1596 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1597 }
1598
1599 /*
1600 * When a non zero sgl_count has been passed perform SGL passthrough
1601 * mapping for pre-allocated fabric memory instead of having target
1602 * core perform an internal SGL allocation..
1603 */
1604 if (sgl_count != 0) {
1605 BUG_ON(!sgl);
1606
1607 /*
1608 * A work-around for tcm_loop as some userspace code via
1609 * scsi-generic do not memset their associated read buffers,
1610 * so go ahead and do that here for type non-data CDBs. Also
1611 * note that this is currently guaranteed to be a single SGL
1612 * for this case by target core in target_setup_cmd_from_cdb()
1613 * -> transport_generic_cmd_sequencer().
1614 */
1615 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1616 se_cmd->data_direction == DMA_FROM_DEVICE) {
1617 unsigned char *buf = NULL;
1618
1619 if (sgl)
1620 buf = kmap(sg_page(sgl)) + sgl->offset;
1621
1622 if (buf) {
1623 memset(buf, 0, sgl->length);
1624 kunmap(sg_page(sgl));
1625 }
1626 }
1627
1628 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1629 sgl_bidi, sgl_bidi_count);
1630 if (rc != 0) {
1631 transport_generic_request_failure(se_cmd, rc);
1632 return 0;
1633 }
1634 }
1635
1636 /*
1637 * Check if we need to delay processing because of ALUA
1638 * Active/NonOptimized primary access state..
1639 */
1640 core_alua_check_nonop_delay(se_cmd);
1641
1642 transport_handle_cdb_direct(se_cmd);
1643 return 0;
1644 }
1645 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1646
1647 /**
1648 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1649 *
1650 * @se_cmd: command descriptor to submit
1651 * @se_sess: associated se_sess for endpoint
1652 * @cdb: pointer to SCSI CDB
1653 * @sense: pointer to SCSI sense buffer
1654 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1655 * @data_length: fabric expected data transfer length
1656 * @task_attr: SAM task attribute
1657 * @data_dir: DMA data direction
1658 * @flags: flags for command submission from target_sc_flags_tables
1659 *
1660 * Task tags are supported if the caller has set @se_cmd->tag.
1661 *
1662 * Returns non zero to signal active I/O shutdown failure. All other
1663 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1664 * but still return zero here.
1665 *
1666 * This may only be called from process context, and also currently
1667 * assumes internal allocation of fabric payload buffer by target-core.
1668 *
1669 * It also assumes interal target core SGL memory allocation.
1670 */
1671 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1672 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1673 u32 data_length, int task_attr, int data_dir, int flags)
1674 {
1675 return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1676 unpacked_lun, data_length, task_attr, data_dir,
1677 flags, NULL, 0, NULL, 0, NULL, 0);
1678 }
1679 EXPORT_SYMBOL(target_submit_cmd);
1680
1681 static void target_complete_tmr_failure(struct work_struct *work)
1682 {
1683 struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1684
1685 se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1686 se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1687
1688 transport_lun_remove_cmd(se_cmd);
1689 transport_cmd_check_stop_to_fabric(se_cmd);
1690 }
1691
1692 static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
1693 u64 *unpacked_lun)
1694 {
1695 struct se_cmd *se_cmd;
1696 unsigned long flags;
1697 bool ret = false;
1698
1699 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
1700 list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
1701 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1702 continue;
1703
1704 if (se_cmd->tag == tag) {
1705 *unpacked_lun = se_cmd->orig_fe_lun;
1706 ret = true;
1707 break;
1708 }
1709 }
1710 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
1711
1712 return ret;
1713 }
1714
1715 /**
1716 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1717 * for TMR CDBs
1718 *
1719 * @se_cmd: command descriptor to submit
1720 * @se_sess: associated se_sess for endpoint
1721 * @sense: pointer to SCSI sense buffer
1722 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1723 * @fabric_tmr_ptr: fabric context for TMR req
1724 * @tm_type: Type of TM request
1725 * @gfp: gfp type for caller
1726 * @tag: referenced task tag for TMR_ABORT_TASK
1727 * @flags: submit cmd flags
1728 *
1729 * Callable from all contexts.
1730 **/
1731
1732 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1733 unsigned char *sense, u64 unpacked_lun,
1734 void *fabric_tmr_ptr, unsigned char tm_type,
1735 gfp_t gfp, u64 tag, int flags)
1736 {
1737 struct se_portal_group *se_tpg;
1738 int ret;
1739
1740 se_tpg = se_sess->se_tpg;
1741 BUG_ON(!se_tpg);
1742
1743 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1744 0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1745 /*
1746 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1747 * allocation failure.
1748 */
1749 ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1750 if (ret < 0)
1751 return -ENOMEM;
1752
1753 if (tm_type == TMR_ABORT_TASK)
1754 se_cmd->se_tmr_req->ref_task_tag = tag;
1755
1756 /* See target_submit_cmd for commentary */
1757 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1758 if (ret) {
1759 core_tmr_release_req(se_cmd->se_tmr_req);
1760 return ret;
1761 }
1762 /*
1763 * If this is ABORT_TASK with no explicit fabric provided LUN,
1764 * go ahead and search active session tags for a match to figure
1765 * out unpacked_lun for the original se_cmd.
1766 */
1767 if (tm_type == TMR_ABORT_TASK && (flags & TARGET_SCF_LOOKUP_LUN_FROM_TAG)) {
1768 if (!target_lookup_lun_from_tag(se_sess, tag, &unpacked_lun))
1769 goto failure;
1770 }
1771
1772 ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1773 if (ret)
1774 goto failure;
1775
1776 transport_generic_handle_tmr(se_cmd);
1777 return 0;
1778
1779 /*
1780 * For callback during failure handling, push this work off
1781 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1782 */
1783 failure:
1784 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1785 schedule_work(&se_cmd->work);
1786 return 0;
1787 }
1788 EXPORT_SYMBOL(target_submit_tmr);
1789
1790 /*
1791 * Handle SAM-esque emulation for generic transport request failures.
1792 */
1793 void transport_generic_request_failure(struct se_cmd *cmd,
1794 sense_reason_t sense_reason)
1795 {
1796 int ret = 0, post_ret;
1797
1798 pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
1799 sense_reason);
1800 target_show_cmd("-----[ ", cmd);
1801
1802 /*
1803 * For SAM Task Attribute emulation for failed struct se_cmd
1804 */
1805 transport_complete_task_attr(cmd);
1806
1807 if (cmd->transport_complete_callback)
1808 cmd->transport_complete_callback(cmd, false, &post_ret);
1809
1810 if (transport_check_aborted_status(cmd, 1))
1811 return;
1812
1813 switch (sense_reason) {
1814 case TCM_NON_EXISTENT_LUN:
1815 case TCM_UNSUPPORTED_SCSI_OPCODE:
1816 case TCM_INVALID_CDB_FIELD:
1817 case TCM_INVALID_PARAMETER_LIST:
1818 case TCM_PARAMETER_LIST_LENGTH_ERROR:
1819 case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1820 case TCM_UNKNOWN_MODE_PAGE:
1821 case TCM_WRITE_PROTECTED:
1822 case TCM_ADDRESS_OUT_OF_RANGE:
1823 case TCM_CHECK_CONDITION_ABORT_CMD:
1824 case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1825 case TCM_CHECK_CONDITION_NOT_READY:
1826 case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1827 case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1828 case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1829 case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1830 case TCM_TOO_MANY_TARGET_DESCS:
1831 case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
1832 case TCM_TOO_MANY_SEGMENT_DESCS:
1833 case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
1834 break;
1835 case TCM_OUT_OF_RESOURCES:
1836 cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
1837 goto queue_status;
1838 case TCM_LUN_BUSY:
1839 cmd->scsi_status = SAM_STAT_BUSY;
1840 goto queue_status;
1841 case TCM_RESERVATION_CONFLICT:
1842 /*
1843 * No SENSE Data payload for this case, set SCSI Status
1844 * and queue the response to $FABRIC_MOD.
1845 *
1846 * Uses linux/include/scsi/scsi.h SAM status codes defs
1847 */
1848 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1849 /*
1850 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1851 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1852 * CONFLICT STATUS.
1853 *
1854 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1855 */
1856 if (cmd->se_sess &&
1857 cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1858 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1859 cmd->orig_fe_lun, 0x2C,
1860 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1861 }
1862
1863 goto queue_status;
1864 default:
1865 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1866 cmd->t_task_cdb[0], sense_reason);
1867 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1868 break;
1869 }
1870
1871 ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1872 if (ret)
1873 goto queue_full;
1874
1875 check_stop:
1876 transport_lun_remove_cmd(cmd);
1877 transport_cmd_check_stop_to_fabric(cmd);
1878 return;
1879
1880 queue_status:
1881 trace_target_cmd_complete(cmd);
1882 ret = cmd->se_tfo->queue_status(cmd);
1883 if (!ret)
1884 goto check_stop;
1885 queue_full:
1886 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
1887 }
1888 EXPORT_SYMBOL(transport_generic_request_failure);
1889
1890 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1891 {
1892 sense_reason_t ret;
1893
1894 if (!cmd->execute_cmd) {
1895 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1896 goto err;
1897 }
1898 if (do_checks) {
1899 /*
1900 * Check for an existing UNIT ATTENTION condition after
1901 * target_handle_task_attr() has done SAM task attr
1902 * checking, and possibly have already defered execution
1903 * out to target_restart_delayed_cmds() context.
1904 */
1905 ret = target_scsi3_ua_check(cmd);
1906 if (ret)
1907 goto err;
1908
1909 ret = target_alua_state_check(cmd);
1910 if (ret)
1911 goto err;
1912
1913 ret = target_check_reservation(cmd);
1914 if (ret) {
1915 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1916 goto err;
1917 }
1918 }
1919
1920 ret = cmd->execute_cmd(cmd);
1921 if (!ret)
1922 return;
1923 err:
1924 spin_lock_irq(&cmd->t_state_lock);
1925 cmd->transport_state &= ~CMD_T_SENT;
1926 spin_unlock_irq(&cmd->t_state_lock);
1927
1928 transport_generic_request_failure(cmd, ret);
1929 }
1930
1931 static int target_write_prot_action(struct se_cmd *cmd)
1932 {
1933 u32 sectors;
1934 /*
1935 * Perform WRITE_INSERT of PI using software emulation when backend
1936 * device has PI enabled, if the transport has not already generated
1937 * PI using hardware WRITE_INSERT offload.
1938 */
1939 switch (cmd->prot_op) {
1940 case TARGET_PROT_DOUT_INSERT:
1941 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1942 sbc_dif_generate(cmd);
1943 break;
1944 case TARGET_PROT_DOUT_STRIP:
1945 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1946 break;
1947
1948 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1949 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1950 sectors, 0, cmd->t_prot_sg, 0);
1951 if (unlikely(cmd->pi_err)) {
1952 spin_lock_irq(&cmd->t_state_lock);
1953 cmd->transport_state &= ~CMD_T_SENT;
1954 spin_unlock_irq(&cmd->t_state_lock);
1955 transport_generic_request_failure(cmd, cmd->pi_err);
1956 return -1;
1957 }
1958 break;
1959 default:
1960 break;
1961 }
1962
1963 return 0;
1964 }
1965
1966 static bool target_handle_task_attr(struct se_cmd *cmd)
1967 {
1968 struct se_device *dev = cmd->se_dev;
1969
1970 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1971 return false;
1972
1973 cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
1974
1975 /*
1976 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1977 * to allow the passed struct se_cmd list of tasks to the front of the list.
1978 */
1979 switch (cmd->sam_task_attr) {
1980 case TCM_HEAD_TAG:
1981 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1982 cmd->t_task_cdb[0]);
1983 return false;
1984 case TCM_ORDERED_TAG:
1985 atomic_inc_mb(&dev->dev_ordered_sync);
1986
1987 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1988 cmd->t_task_cdb[0]);
1989
1990 /*
1991 * Execute an ORDERED command if no other older commands
1992 * exist that need to be completed first.
1993 */
1994 if (!atomic_read(&dev->simple_cmds))
1995 return false;
1996 break;
1997 default:
1998 /*
1999 * For SIMPLE and UNTAGGED Task Attribute commands
2000 */
2001 atomic_inc_mb(&dev->simple_cmds);
2002 break;
2003 }
2004
2005 if (atomic_read(&dev->dev_ordered_sync) == 0)
2006 return false;
2007
2008 spin_lock(&dev->delayed_cmd_lock);
2009 list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
2010 spin_unlock(&dev->delayed_cmd_lock);
2011
2012 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
2013 cmd->t_task_cdb[0], cmd->sam_task_attr);
2014 return true;
2015 }
2016
2017 static int __transport_check_aborted_status(struct se_cmd *, int);
2018
2019 void target_execute_cmd(struct se_cmd *cmd)
2020 {
2021 /*
2022 * Determine if frontend context caller is requesting the stopping of
2023 * this command for frontend exceptions.
2024 *
2025 * If the received CDB has already been aborted stop processing it here.
2026 */
2027 spin_lock_irq(&cmd->t_state_lock);
2028 if (__transport_check_aborted_status(cmd, 1)) {
2029 spin_unlock_irq(&cmd->t_state_lock);
2030 return;
2031 }
2032 if (cmd->transport_state & CMD_T_STOP) {
2033 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2034 __func__, __LINE__, cmd->tag);
2035
2036 spin_unlock_irq(&cmd->t_state_lock);
2037 complete_all(&cmd->t_transport_stop_comp);
2038 return;
2039 }
2040
2041 cmd->t_state = TRANSPORT_PROCESSING;
2042 cmd->transport_state &= ~CMD_T_PRE_EXECUTE;
2043 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
2044 spin_unlock_irq(&cmd->t_state_lock);
2045
2046 if (target_write_prot_action(cmd))
2047 return;
2048
2049 if (target_handle_task_attr(cmd)) {
2050 spin_lock_irq(&cmd->t_state_lock);
2051 cmd->transport_state &= ~CMD_T_SENT;
2052 spin_unlock_irq(&cmd->t_state_lock);
2053 return;
2054 }
2055
2056 __target_execute_cmd(cmd, true);
2057 }
2058 EXPORT_SYMBOL(target_execute_cmd);
2059
2060 /*
2061 * Process all commands up to the last received ORDERED task attribute which
2062 * requires another blocking boundary
2063 */
2064 static void target_restart_delayed_cmds(struct se_device *dev)
2065 {
2066 for (;;) {
2067 struct se_cmd *cmd;
2068
2069 spin_lock(&dev->delayed_cmd_lock);
2070 if (list_empty(&dev->delayed_cmd_list)) {
2071 spin_unlock(&dev->delayed_cmd_lock);
2072 break;
2073 }
2074
2075 cmd = list_entry(dev->delayed_cmd_list.next,
2076 struct se_cmd, se_delayed_node);
2077 list_del(&cmd->se_delayed_node);
2078 spin_unlock(&dev->delayed_cmd_lock);
2079
2080 cmd->transport_state |= CMD_T_SENT;
2081
2082 __target_execute_cmd(cmd, true);
2083
2084 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
2085 break;
2086 }
2087 }
2088
2089 /*
2090 * Called from I/O completion to determine which dormant/delayed
2091 * and ordered cmds need to have their tasks added to the execution queue.
2092 */
2093 static void transport_complete_task_attr(struct se_cmd *cmd)
2094 {
2095 struct se_device *dev = cmd->se_dev;
2096
2097 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2098 return;
2099
2100 if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2101 goto restart;
2102
2103 if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
2104 atomic_dec_mb(&dev->simple_cmds);
2105 dev->dev_cur_ordered_id++;
2106 } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
2107 dev->dev_cur_ordered_id++;
2108 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
2109 dev->dev_cur_ordered_id);
2110 } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2111 atomic_dec_mb(&dev->dev_ordered_sync);
2112
2113 dev->dev_cur_ordered_id++;
2114 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
2115 dev->dev_cur_ordered_id);
2116 }
2117 cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2118
2119 restart:
2120 target_restart_delayed_cmds(dev);
2121 }
2122
2123 static void transport_complete_qf(struct se_cmd *cmd)
2124 {
2125 int ret = 0;
2126
2127 transport_complete_task_attr(cmd);
2128 /*
2129 * If a fabric driver ->write_pending() or ->queue_data_in() callback
2130 * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2131 * the same callbacks should not be retried. Return CHECK_CONDITION
2132 * if a scsi_status is not already set.
2133 *
2134 * If a fabric driver ->queue_status() has returned non zero, always
2135 * keep retrying no matter what..
2136 */
2137 if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2138 if (cmd->scsi_status)
2139 goto queue_status;
2140
2141 translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2142 goto queue_status;
2143 }
2144
2145 /*
2146 * Check if we need to send a sense buffer from
2147 * the struct se_cmd in question. We do NOT want
2148 * to take this path of the IO has been marked as
2149 * needing to be treated like a "normal read". This
2150 * is the case if it's a tape read, and either the
2151 * FM, EOM, or ILI bits are set, but there is no
2152 * sense data.
2153 */
2154 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2155 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2156 goto queue_status;
2157
2158 switch (cmd->data_direction) {
2159 case DMA_FROM_DEVICE:
2160 /* queue status if not treating this as a normal read */
2161 if (cmd->scsi_status &&
2162 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2163 goto queue_status;
2164
2165 trace_target_cmd_complete(cmd);
2166 ret = cmd->se_tfo->queue_data_in(cmd);
2167 break;
2168 case DMA_TO_DEVICE:
2169 if (cmd->se_cmd_flags & SCF_BIDI) {
2170 ret = cmd->se_tfo->queue_data_in(cmd);
2171 break;
2172 }
2173 /* fall through */
2174 case DMA_NONE:
2175 queue_status:
2176 trace_target_cmd_complete(cmd);
2177 ret = cmd->se_tfo->queue_status(cmd);
2178 break;
2179 default:
2180 break;
2181 }
2182
2183 if (ret < 0) {
2184 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2185 return;
2186 }
2187 transport_lun_remove_cmd(cmd);
2188 transport_cmd_check_stop_to_fabric(cmd);
2189 }
2190
2191 static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2192 int err, bool write_pending)
2193 {
2194 /*
2195 * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2196 * ->queue_data_in() callbacks from new process context.
2197 *
2198 * Otherwise for other errors, transport_complete_qf() will send
2199 * CHECK_CONDITION via ->queue_status() instead of attempting to
2200 * retry associated fabric driver data-transfer callbacks.
2201 */
2202 if (err == -EAGAIN || err == -ENOMEM) {
2203 cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2204 TRANSPORT_COMPLETE_QF_OK;
2205 } else {
2206 pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2207 cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2208 }
2209
2210 spin_lock_irq(&dev->qf_cmd_lock);
2211 list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2212 atomic_inc_mb(&dev->dev_qf_count);
2213 spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2214
2215 schedule_work(&cmd->se_dev->qf_work_queue);
2216 }
2217
2218 static bool target_read_prot_action(struct se_cmd *cmd)
2219 {
2220 switch (cmd->prot_op) {
2221 case TARGET_PROT_DIN_STRIP:
2222 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2223 u32 sectors = cmd->data_length >>
2224 ilog2(cmd->se_dev->dev_attrib.block_size);
2225
2226 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2227 sectors, 0, cmd->t_prot_sg,
2228 0);
2229 if (cmd->pi_err)
2230 return true;
2231 }
2232 break;
2233 case TARGET_PROT_DIN_INSERT:
2234 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2235 break;
2236
2237 sbc_dif_generate(cmd);
2238 break;
2239 default:
2240 break;
2241 }
2242
2243 return false;
2244 }
2245
2246 static void target_complete_ok_work(struct work_struct *work)
2247 {
2248 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2249 int ret;
2250
2251 /*
2252 * Check if we need to move delayed/dormant tasks from cmds on the
2253 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2254 * Attribute.
2255 */
2256 transport_complete_task_attr(cmd);
2257
2258 /*
2259 * Check to schedule QUEUE_FULL work, or execute an existing
2260 * cmd->transport_qf_callback()
2261 */
2262 if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2263 schedule_work(&cmd->se_dev->qf_work_queue);
2264
2265 /*
2266 * Check if we need to send a sense buffer from
2267 * the struct se_cmd in question. We do NOT want
2268 * to take this path of the IO has been marked as
2269 * needing to be treated like a "normal read". This
2270 * is the case if it's a tape read, and either the
2271 * FM, EOM, or ILI bits are set, but there is no
2272 * sense data.
2273 */
2274 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2275 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2276 WARN_ON(!cmd->scsi_status);
2277 ret = transport_send_check_condition_and_sense(
2278 cmd, 0, 1);
2279 if (ret)
2280 goto queue_full;
2281
2282 transport_lun_remove_cmd(cmd);
2283 transport_cmd_check_stop_to_fabric(cmd);
2284 return;
2285 }
2286 /*
2287 * Check for a callback, used by amongst other things
2288 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2289 */
2290 if (cmd->transport_complete_callback) {
2291 sense_reason_t rc;
2292 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2293 bool zero_dl = !(cmd->data_length);
2294 int post_ret = 0;
2295
2296 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2297 if (!rc && !post_ret) {
2298 if (caw && zero_dl)
2299 goto queue_rsp;
2300
2301 return;
2302 } else if (rc) {
2303 ret = transport_send_check_condition_and_sense(cmd,
2304 rc, 0);
2305 if (ret)
2306 goto queue_full;
2307
2308 transport_lun_remove_cmd(cmd);
2309 transport_cmd_check_stop_to_fabric(cmd);
2310 return;
2311 }
2312 }
2313
2314 queue_rsp:
2315 switch (cmd->data_direction) {
2316 case DMA_FROM_DEVICE:
2317 /*
2318 * if this is a READ-type IO, but SCSI status
2319 * is set, then skip returning data and just
2320 * return the status -- unless this IO is marked
2321 * as needing to be treated as a normal read,
2322 * in which case we want to go ahead and return
2323 * the data. This happens, for example, for tape
2324 * reads with the FM, EOM, or ILI bits set, with
2325 * no sense data.
2326 */
2327 if (cmd->scsi_status &&
2328 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2329 goto queue_status;
2330
2331 atomic_long_add(cmd->data_length,
2332 &cmd->se_lun->lun_stats.tx_data_octets);
2333 /*
2334 * Perform READ_STRIP of PI using software emulation when
2335 * backend had PI enabled, if the transport will not be
2336 * performing hardware READ_STRIP offload.
2337 */
2338 if (target_read_prot_action(cmd)) {
2339 ret = transport_send_check_condition_and_sense(cmd,
2340 cmd->pi_err, 0);
2341 if (ret)
2342 goto queue_full;
2343
2344 transport_lun_remove_cmd(cmd);
2345 transport_cmd_check_stop_to_fabric(cmd);
2346 return;
2347 }
2348
2349 trace_target_cmd_complete(cmd);
2350 ret = cmd->se_tfo->queue_data_in(cmd);
2351 if (ret)
2352 goto queue_full;
2353 break;
2354 case DMA_TO_DEVICE:
2355 atomic_long_add(cmd->data_length,
2356 &cmd->se_lun->lun_stats.rx_data_octets);
2357 /*
2358 * Check if we need to send READ payload for BIDI-COMMAND
2359 */
2360 if (cmd->se_cmd_flags & SCF_BIDI) {
2361 atomic_long_add(cmd->data_length,
2362 &cmd->se_lun->lun_stats.tx_data_octets);
2363 ret = cmd->se_tfo->queue_data_in(cmd);
2364 if (ret)
2365 goto queue_full;
2366 break;
2367 }
2368 /* fall through */
2369 case DMA_NONE:
2370 queue_status:
2371 trace_target_cmd_complete(cmd);
2372 ret = cmd->se_tfo->queue_status(cmd);
2373 if (ret)
2374 goto queue_full;
2375 break;
2376 default:
2377 break;
2378 }
2379
2380 transport_lun_remove_cmd(cmd);
2381 transport_cmd_check_stop_to_fabric(cmd);
2382 return;
2383
2384 queue_full:
2385 pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2386 " data_direction: %d\n", cmd, cmd->data_direction);
2387
2388 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2389 }
2390
2391 void target_free_sgl(struct scatterlist *sgl, int nents)
2392 {
2393 sgl_free_n_order(sgl, nents, 0);
2394 }
2395 EXPORT_SYMBOL(target_free_sgl);
2396
2397 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2398 {
2399 /*
2400 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2401 * emulation, and free + reset pointers if necessary..
2402 */
2403 if (!cmd->t_data_sg_orig)
2404 return;
2405
2406 kfree(cmd->t_data_sg);
2407 cmd->t_data_sg = cmd->t_data_sg_orig;
2408 cmd->t_data_sg_orig = NULL;
2409 cmd->t_data_nents = cmd->t_data_nents_orig;
2410 cmd->t_data_nents_orig = 0;
2411 }
2412
2413 static inline void transport_free_pages(struct se_cmd *cmd)
2414 {
2415 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2416 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2417 cmd->t_prot_sg = NULL;
2418 cmd->t_prot_nents = 0;
2419 }
2420
2421 if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2422 /*
2423 * Release special case READ buffer payload required for
2424 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2425 */
2426 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2427 target_free_sgl(cmd->t_bidi_data_sg,
2428 cmd->t_bidi_data_nents);
2429 cmd->t_bidi_data_sg = NULL;
2430 cmd->t_bidi_data_nents = 0;
2431 }
2432 transport_reset_sgl_orig(cmd);
2433 return;
2434 }
2435 transport_reset_sgl_orig(cmd);
2436
2437 target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2438 cmd->t_data_sg = NULL;
2439 cmd->t_data_nents = 0;
2440
2441 target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2442 cmd->t_bidi_data_sg = NULL;
2443 cmd->t_bidi_data_nents = 0;
2444 }
2445
2446 void *transport_kmap_data_sg(struct se_cmd *cmd)
2447 {
2448 struct scatterlist *sg = cmd->t_data_sg;
2449 struct page **pages;
2450 int i;
2451
2452 /*
2453 * We need to take into account a possible offset here for fabrics like
2454 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2455 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2456 */
2457 if (!cmd->t_data_nents)
2458 return NULL;
2459
2460 BUG_ON(!sg);
2461 if (cmd->t_data_nents == 1)
2462 return kmap(sg_page(sg)) + sg->offset;
2463
2464 /* >1 page. use vmap */
2465 pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2466 if (!pages)
2467 return NULL;
2468
2469 /* convert sg[] to pages[] */
2470 for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2471 pages[i] = sg_page(sg);
2472 }
2473
2474 cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
2475 kfree(pages);
2476 if (!cmd->t_data_vmap)
2477 return NULL;
2478
2479 return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2480 }
2481 EXPORT_SYMBOL(transport_kmap_data_sg);
2482
2483 void transport_kunmap_data_sg(struct se_cmd *cmd)
2484 {
2485 if (!cmd->t_data_nents) {
2486 return;
2487 } else if (cmd->t_data_nents == 1) {
2488 kunmap(sg_page(cmd->t_data_sg));
2489 return;
2490 }
2491
2492 vunmap(cmd->t_data_vmap);
2493 cmd->t_data_vmap = NULL;
2494 }
2495 EXPORT_SYMBOL(transport_kunmap_data_sg);
2496
2497 int
2498 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2499 bool zero_page, bool chainable)
2500 {
2501 gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2502
2503 *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2504 return *sgl ? 0 : -ENOMEM;
2505 }
2506 EXPORT_SYMBOL(target_alloc_sgl);
2507
2508 /*
2509 * Allocate any required resources to execute the command. For writes we
2510 * might not have the payload yet, so notify the fabric via a call to
2511 * ->write_pending instead. Otherwise place it on the execution queue.
2512 */
2513 sense_reason_t
2514 transport_generic_new_cmd(struct se_cmd *cmd)
2515 {
2516 unsigned long flags;
2517 int ret = 0;
2518 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2519
2520 if (cmd->prot_op != TARGET_PROT_NORMAL &&
2521 !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2522 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2523 cmd->prot_length, true, false);
2524 if (ret < 0)
2525 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2526 }
2527
2528 /*
2529 * Determine if the TCM fabric module has already allocated physical
2530 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2531 * beforehand.
2532 */
2533 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2534 cmd->data_length) {
2535
2536 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2537 (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2538 u32 bidi_length;
2539
2540 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2541 bidi_length = cmd->t_task_nolb *
2542 cmd->se_dev->dev_attrib.block_size;
2543 else
2544 bidi_length = cmd->data_length;
2545
2546 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2547 &cmd->t_bidi_data_nents,
2548 bidi_length, zero_flag, false);
2549 if (ret < 0)
2550 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2551 }
2552
2553 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2554 cmd->data_length, zero_flag, false);
2555 if (ret < 0)
2556 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2557 } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2558 cmd->data_length) {
2559 /*
2560 * Special case for COMPARE_AND_WRITE with fabrics
2561 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2562 */
2563 u32 caw_length = cmd->t_task_nolb *
2564 cmd->se_dev->dev_attrib.block_size;
2565
2566 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2567 &cmd->t_bidi_data_nents,
2568 caw_length, zero_flag, false);
2569 if (ret < 0)
2570 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2571 }
2572 /*
2573 * If this command is not a write we can execute it right here,
2574 * for write buffers we need to notify the fabric driver first
2575 * and let it call back once the write buffers are ready.
2576 */
2577 target_add_to_state_list(cmd);
2578 if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2579 target_execute_cmd(cmd);
2580 return 0;
2581 }
2582
2583 spin_lock_irqsave(&cmd->t_state_lock, flags);
2584 cmd->t_state = TRANSPORT_WRITE_PENDING;
2585 /*
2586 * Determine if frontend context caller is requesting the stopping of
2587 * this command for frontend exceptions.
2588 */
2589 if (cmd->transport_state & CMD_T_STOP) {
2590 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2591 __func__, __LINE__, cmd->tag);
2592
2593 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2594
2595 complete_all(&cmd->t_transport_stop_comp);
2596 return 0;
2597 }
2598 cmd->transport_state &= ~CMD_T_ACTIVE;
2599 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2600
2601 ret = cmd->se_tfo->write_pending(cmd);
2602 if (ret)
2603 goto queue_full;
2604
2605 return 0;
2606
2607 queue_full:
2608 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2609 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2610 return 0;
2611 }
2612 EXPORT_SYMBOL(transport_generic_new_cmd);
2613
2614 static void transport_write_pending_qf(struct se_cmd *cmd)
2615 {
2616 unsigned long flags;
2617 int ret;
2618 bool stop;
2619
2620 spin_lock_irqsave(&cmd->t_state_lock, flags);
2621 stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2622 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2623
2624 if (stop) {
2625 pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2626 __func__, __LINE__, cmd->tag);
2627 complete_all(&cmd->t_transport_stop_comp);
2628 return;
2629 }
2630
2631 ret = cmd->se_tfo->write_pending(cmd);
2632 if (ret) {
2633 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2634 cmd);
2635 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2636 }
2637 }
2638
2639 static bool
2640 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2641 unsigned long *flags);
2642
2643 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2644 {
2645 unsigned long flags;
2646
2647 spin_lock_irqsave(&cmd->t_state_lock, flags);
2648 __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2649 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2650 }
2651
2652 /*
2653 * This function is called by frontend drivers after processing of a command
2654 * has finished.
2655 *
2656 * The protocol for ensuring that either the regular flow or the TMF
2657 * code drops one reference is as follows:
2658 * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
2659 * the frontend driver to drop one reference, synchronously or asynchronously.
2660 * - During regular command processing the target core sets CMD_T_COMPLETE
2661 * before invoking one of the .queue_*() functions.
2662 * - The code that aborts commands skips commands and TMFs for which
2663 * CMD_T_COMPLETE has been set.
2664 * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
2665 * commands that will be aborted.
2666 * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
2667 * transport_generic_free_cmd() skips its call to target_put_sess_cmd().
2668 * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
2669 * be called and will drop a reference.
2670 * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
2671 * will be called. transport_cmd_finish_abort() will drop the final reference.
2672 */
2673 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2674 {
2675 DECLARE_COMPLETION_ONSTACK(compl);
2676 int ret = 0;
2677 bool aborted = false, tas = false;
2678
2679 if (wait_for_tasks)
2680 target_wait_free_cmd(cmd, &aborted, &tas);
2681
2682 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
2683 /*
2684 * Handle WRITE failure case where transport_generic_new_cmd()
2685 * has already added se_cmd to state_list, but fabric has
2686 * failed command before I/O submission.
2687 */
2688 if (cmd->state_active)
2689 target_remove_from_state_list(cmd);
2690
2691 if (cmd->se_lun)
2692 transport_lun_remove_cmd(cmd);
2693 }
2694 if (aborted)
2695 cmd->compl = &compl;
2696 if (!aborted || tas)
2697 ret = target_put_sess_cmd(cmd);
2698 if (aborted) {
2699 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2700 wait_for_completion(&compl);
2701 ret = 1;
2702 }
2703 return ret;
2704 }
2705 EXPORT_SYMBOL(transport_generic_free_cmd);
2706
2707 /**
2708 * target_get_sess_cmd - Add command to active ->sess_cmd_list
2709 * @se_cmd: command descriptor to add
2710 * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
2711 */
2712 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2713 {
2714 struct se_session *se_sess = se_cmd->se_sess;
2715 unsigned long flags;
2716 int ret = 0;
2717
2718 /*
2719 * Add a second kref if the fabric caller is expecting to handle
2720 * fabric acknowledgement that requires two target_put_sess_cmd()
2721 * invocations before se_cmd descriptor release.
2722 */
2723 if (ack_kref) {
2724 if (!kref_get_unless_zero(&se_cmd->cmd_kref))
2725 return -EINVAL;
2726
2727 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2728 }
2729
2730 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2731 if (se_sess->sess_tearing_down) {
2732 ret = -ESHUTDOWN;
2733 goto out;
2734 }
2735 se_cmd->transport_state |= CMD_T_PRE_EXECUTE;
2736 list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2737 percpu_ref_get(&se_sess->cmd_count);
2738 out:
2739 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2740
2741 if (ret && ack_kref)
2742 target_put_sess_cmd(se_cmd);
2743
2744 return ret;
2745 }
2746 EXPORT_SYMBOL(target_get_sess_cmd);
2747
2748 static void target_free_cmd_mem(struct se_cmd *cmd)
2749 {
2750 transport_free_pages(cmd);
2751
2752 if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2753 core_tmr_release_req(cmd->se_tmr_req);
2754 if (cmd->t_task_cdb != cmd->__t_task_cdb)
2755 kfree(cmd->t_task_cdb);
2756 }
2757
2758 static void target_release_cmd_kref(struct kref *kref)
2759 {
2760 struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2761 struct se_session *se_sess = se_cmd->se_sess;
2762 struct completion *compl = se_cmd->compl;
2763 unsigned long flags;
2764
2765 if (se_sess) {
2766 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2767 list_del_init(&se_cmd->se_cmd_list);
2768 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2769 }
2770
2771 target_free_cmd_mem(se_cmd);
2772 se_cmd->se_tfo->release_cmd(se_cmd);
2773 if (compl)
2774 complete(compl);
2775
2776 percpu_ref_put(&se_sess->cmd_count);
2777 }
2778
2779 /**
2780 * target_put_sess_cmd - decrease the command reference count
2781 * @se_cmd: command to drop a reference from
2782 *
2783 * Returns 1 if and only if this target_put_sess_cmd() call caused the
2784 * refcount to drop to zero. Returns zero otherwise.
2785 */
2786 int target_put_sess_cmd(struct se_cmd *se_cmd)
2787 {
2788 return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2789 }
2790 EXPORT_SYMBOL(target_put_sess_cmd);
2791
2792 static const char *data_dir_name(enum dma_data_direction d)
2793 {
2794 switch (d) {
2795 case DMA_BIDIRECTIONAL: return "BIDI";
2796 case DMA_TO_DEVICE: return "WRITE";
2797 case DMA_FROM_DEVICE: return "READ";
2798 case DMA_NONE: return "NONE";
2799 }
2800
2801 return "(?)";
2802 }
2803
2804 static const char *cmd_state_name(enum transport_state_table t)
2805 {
2806 switch (t) {
2807 case TRANSPORT_NO_STATE: return "NO_STATE";
2808 case TRANSPORT_NEW_CMD: return "NEW_CMD";
2809 case TRANSPORT_WRITE_PENDING: return "WRITE_PENDING";
2810 case TRANSPORT_PROCESSING: return "PROCESSING";
2811 case TRANSPORT_COMPLETE: return "COMPLETE";
2812 case TRANSPORT_ISTATE_PROCESSING:
2813 return "ISTATE_PROCESSING";
2814 case TRANSPORT_COMPLETE_QF_WP: return "COMPLETE_QF_WP";
2815 case TRANSPORT_COMPLETE_QF_OK: return "COMPLETE_QF_OK";
2816 case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR";
2817 }
2818
2819 return "(?)";
2820 }
2821
2822 static void target_append_str(char **str, const char *txt)
2823 {
2824 char *prev = *str;
2825
2826 *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
2827 kstrdup(txt, GFP_ATOMIC);
2828 kfree(prev);
2829 }
2830
2831 /*
2832 * Convert a transport state bitmask into a string. The caller is
2833 * responsible for freeing the returned pointer.
2834 */
2835 static char *target_ts_to_str(u32 ts)
2836 {
2837 char *str = NULL;
2838
2839 if (ts & CMD_T_ABORTED)
2840 target_append_str(&str, "aborted");
2841 if (ts & CMD_T_ACTIVE)
2842 target_append_str(&str, "active");
2843 if (ts & CMD_T_COMPLETE)
2844 target_append_str(&str, "complete");
2845 if (ts & CMD_T_SENT)
2846 target_append_str(&str, "sent");
2847 if (ts & CMD_T_STOP)
2848 target_append_str(&str, "stop");
2849 if (ts & CMD_T_FABRIC_STOP)
2850 target_append_str(&str, "fabric_stop");
2851
2852 return str;
2853 }
2854
2855 static const char *target_tmf_name(enum tcm_tmreq_table tmf)
2856 {
2857 switch (tmf) {
2858 case TMR_ABORT_TASK: return "ABORT_TASK";
2859 case TMR_ABORT_TASK_SET: return "ABORT_TASK_SET";
2860 case TMR_CLEAR_ACA: return "CLEAR_ACA";
2861 case TMR_CLEAR_TASK_SET: return "CLEAR_TASK_SET";
2862 case TMR_LUN_RESET: return "LUN_RESET";
2863 case TMR_TARGET_WARM_RESET: return "TARGET_WARM_RESET";
2864 case TMR_TARGET_COLD_RESET: return "TARGET_COLD_RESET";
2865 case TMR_UNKNOWN: break;
2866 }
2867 return "(?)";
2868 }
2869
2870 void target_show_cmd(const char *pfx, struct se_cmd *cmd)
2871 {
2872 char *ts_str = target_ts_to_str(cmd->transport_state);
2873 const u8 *cdb = cmd->t_task_cdb;
2874 struct se_tmr_req *tmf = cmd->se_tmr_req;
2875
2876 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2877 pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
2878 pfx, cdb[0], cdb[1], cmd->tag,
2879 data_dir_name(cmd->data_direction),
2880 cmd->se_tfo->get_cmd_state(cmd),
2881 cmd_state_name(cmd->t_state), cmd->data_length,
2882 kref_read(&cmd->cmd_kref), ts_str);
2883 } else {
2884 pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
2885 pfx, target_tmf_name(tmf->function), cmd->tag,
2886 tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
2887 cmd_state_name(cmd->t_state),
2888 kref_read(&cmd->cmd_kref), ts_str);
2889 }
2890 kfree(ts_str);
2891 }
2892 EXPORT_SYMBOL(target_show_cmd);
2893
2894 /**
2895 * target_sess_cmd_list_set_waiting - Set sess_tearing_down so no new commands are queued.
2896 * @se_sess: session to flag
2897 */
2898 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2899 {
2900 unsigned long flags;
2901
2902 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2903 se_sess->sess_tearing_down = 1;
2904 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2905
2906 percpu_ref_kill(&se_sess->cmd_count);
2907 }
2908 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2909
2910 /**
2911 * target_wait_for_sess_cmds - Wait for outstanding commands
2912 * @se_sess: session to wait for active I/O
2913 */
2914 void target_wait_for_sess_cmds(struct se_session *se_sess)
2915 {
2916 struct se_cmd *cmd;
2917 int ret;
2918
2919 WARN_ON_ONCE(!se_sess->sess_tearing_down);
2920
2921 do {
2922 ret = wait_event_timeout(se_sess->cmd_list_wq,
2923 percpu_ref_is_zero(&se_sess->cmd_count),
2924 180 * HZ);
2925 list_for_each_entry(cmd, &se_sess->sess_cmd_list, se_cmd_list)
2926 target_show_cmd("session shutdown: still waiting for ",
2927 cmd);
2928 } while (ret <= 0);
2929 }
2930 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2931
2932 static void target_lun_confirm(struct percpu_ref *ref)
2933 {
2934 struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
2935
2936 complete(&lun->lun_ref_comp);
2937 }
2938
2939 void transport_clear_lun_ref(struct se_lun *lun)
2940 {
2941 /*
2942 * Mark the percpu-ref as DEAD, switch to atomic_t mode, drop
2943 * the initial reference and schedule confirm kill to be
2944 * executed after one full RCU grace period has completed.
2945 */
2946 percpu_ref_kill_and_confirm(&lun->lun_ref, target_lun_confirm);
2947 /*
2948 * The first completion waits for percpu_ref_switch_to_atomic_rcu()
2949 * to call target_lun_confirm after lun->lun_ref has been marked
2950 * as __PERCPU_REF_DEAD on all CPUs, and switches to atomic_t
2951 * mode so that percpu_ref_tryget_live() lookup of lun->lun_ref
2952 * fails for all new incoming I/O.
2953 */
2954 wait_for_completion(&lun->lun_ref_comp);
2955 /*
2956 * The second completion waits for percpu_ref_put_many() to
2957 * invoke ->release() after lun->lun_ref has switched to
2958 * atomic_t mode, and lun->lun_ref.count has reached zero.
2959 *
2960 * At this point all target-core lun->lun_ref references have
2961 * been dropped via transport_lun_remove_cmd(), and it's safe
2962 * to proceed with the remaining LUN shutdown.
2963 */
2964 wait_for_completion(&lun->lun_shutdown_comp);
2965 }
2966
2967 static bool
2968 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2969 bool *aborted, bool *tas, unsigned long *flags)
2970 __releases(&cmd->t_state_lock)
2971 __acquires(&cmd->t_state_lock)
2972 {
2973
2974 assert_spin_locked(&cmd->t_state_lock);
2975 WARN_ON_ONCE(!irqs_disabled());
2976
2977 if (fabric_stop)
2978 cmd->transport_state |= CMD_T_FABRIC_STOP;
2979
2980 if (cmd->transport_state & CMD_T_ABORTED)
2981 *aborted = true;
2982
2983 if (cmd->transport_state & CMD_T_TAS)
2984 *tas = true;
2985
2986 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2987 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2988 return false;
2989
2990 if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2991 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2992 return false;
2993
2994 if (!(cmd->transport_state & CMD_T_ACTIVE))
2995 return false;
2996
2997 if (fabric_stop && *aborted)
2998 return false;
2999
3000 cmd->transport_state |= CMD_T_STOP;
3001
3002 target_show_cmd("wait_for_tasks: Stopping ", cmd);
3003
3004 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
3005
3006 while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
3007 180 * HZ))
3008 target_show_cmd("wait for tasks: ", cmd);
3009
3010 spin_lock_irqsave(&cmd->t_state_lock, *flags);
3011 cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
3012
3013 pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
3014 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
3015
3016 return true;
3017 }
3018
3019 /**
3020 * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
3021 * @cmd: command to wait on
3022 */
3023 bool transport_wait_for_tasks(struct se_cmd *cmd)
3024 {
3025 unsigned long flags;
3026 bool ret, aborted = false, tas = false;
3027
3028 spin_lock_irqsave(&cmd->t_state_lock, flags);
3029 ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
3030 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3031
3032 return ret;
3033 }
3034 EXPORT_SYMBOL(transport_wait_for_tasks);
3035
3036 struct sense_info {
3037 u8 key;
3038 u8 asc;
3039 u8 ascq;
3040 bool add_sector_info;
3041 };
3042
3043 static const struct sense_info sense_info_table[] = {
3044 [TCM_NO_SENSE] = {
3045 .key = NOT_READY
3046 },
3047 [TCM_NON_EXISTENT_LUN] = {
3048 .key = ILLEGAL_REQUEST,
3049 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
3050 },
3051 [TCM_UNSUPPORTED_SCSI_OPCODE] = {
3052 .key = ILLEGAL_REQUEST,
3053 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3054 },
3055 [TCM_SECTOR_COUNT_TOO_MANY] = {
3056 .key = ILLEGAL_REQUEST,
3057 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3058 },
3059 [TCM_UNKNOWN_MODE_PAGE] = {
3060 .key = ILLEGAL_REQUEST,
3061 .asc = 0x24, /* INVALID FIELD IN CDB */
3062 },
3063 [TCM_CHECK_CONDITION_ABORT_CMD] = {
3064 .key = ABORTED_COMMAND,
3065 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3066 .ascq = 0x03,
3067 },
3068 [TCM_INCORRECT_AMOUNT_OF_DATA] = {
3069 .key = ABORTED_COMMAND,
3070 .asc = 0x0c, /* WRITE ERROR */
3071 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3072 },
3073 [TCM_INVALID_CDB_FIELD] = {
3074 .key = ILLEGAL_REQUEST,
3075 .asc = 0x24, /* INVALID FIELD IN CDB */
3076 },
3077 [TCM_INVALID_PARAMETER_LIST] = {
3078 .key = ILLEGAL_REQUEST,
3079 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3080 },
3081 [TCM_TOO_MANY_TARGET_DESCS] = {
3082 .key = ILLEGAL_REQUEST,
3083 .asc = 0x26,
3084 .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3085 },
3086 [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3087 .key = ILLEGAL_REQUEST,
3088 .asc = 0x26,
3089 .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3090 },
3091 [TCM_TOO_MANY_SEGMENT_DESCS] = {
3092 .key = ILLEGAL_REQUEST,
3093 .asc = 0x26,
3094 .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3095 },
3096 [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3097 .key = ILLEGAL_REQUEST,
3098 .asc = 0x26,
3099 .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3100 },
3101 [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3102 .key = ILLEGAL_REQUEST,
3103 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3104 },
3105 [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3106 .key = ILLEGAL_REQUEST,
3107 .asc = 0x0c, /* WRITE ERROR */
3108 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3109 },
3110 [TCM_SERVICE_CRC_ERROR] = {
3111 .key = ABORTED_COMMAND,
3112 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3113 .ascq = 0x05, /* N/A */
3114 },
3115 [TCM_SNACK_REJECTED] = {
3116 .key = ABORTED_COMMAND,
3117 .asc = 0x11, /* READ ERROR */
3118 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3119 },
3120 [TCM_WRITE_PROTECTED] = {
3121 .key = DATA_PROTECT,
3122 .asc = 0x27, /* WRITE PROTECTED */
3123 },
3124 [TCM_ADDRESS_OUT_OF_RANGE] = {
3125 .key = ILLEGAL_REQUEST,
3126 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3127 },
3128 [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3129 .key = UNIT_ATTENTION,
3130 },
3131 [TCM_CHECK_CONDITION_NOT_READY] = {
3132 .key = NOT_READY,
3133 },
3134 [TCM_MISCOMPARE_VERIFY] = {
3135 .key = MISCOMPARE,
3136 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3137 .ascq = 0x00,
3138 },
3139 [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
3140 .key = ABORTED_COMMAND,
3141 .asc = 0x10,
3142 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
3143 .add_sector_info = true,
3144 },
3145 [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
3146 .key = ABORTED_COMMAND,
3147 .asc = 0x10,
3148 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
3149 .add_sector_info = true,
3150 },
3151 [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
3152 .key = ABORTED_COMMAND,
3153 .asc = 0x10,
3154 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
3155 .add_sector_info = true,
3156 },
3157 [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
3158 .key = COPY_ABORTED,
3159 .asc = 0x0d,
3160 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
3161
3162 },
3163 [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
3164 /*
3165 * Returning ILLEGAL REQUEST would cause immediate IO errors on
3166 * Solaris initiators. Returning NOT READY instead means the
3167 * operations will be retried a finite number of times and we
3168 * can survive intermittent errors.
3169 */
3170 .key = NOT_READY,
3171 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
3172 },
3173 [TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
3174 /*
3175 * From spc4r22 section5.7.7,5.7.8
3176 * If a PERSISTENT RESERVE OUT command with a REGISTER service action
3177 * or a REGISTER AND IGNORE EXISTING KEY service action or
3178 * REGISTER AND MOVE service actionis attempted,
3179 * but there are insufficient device server resources to complete the
3180 * operation, then the command shall be terminated with CHECK CONDITION
3181 * status, with the sense key set to ILLEGAL REQUEST,and the additonal
3182 * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
3183 */
3184 .key = ILLEGAL_REQUEST,
3185 .asc = 0x55,
3186 .ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
3187 },
3188 };
3189
3190 /**
3191 * translate_sense_reason - translate a sense reason into T10 key, asc and ascq
3192 * @cmd: SCSI command in which the resulting sense buffer or SCSI status will
3193 * be stored.
3194 * @reason: LIO sense reason code. If this argument has the value
3195 * TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If
3196 * dequeuing a unit attention fails due to multiple commands being processed
3197 * concurrently, set the command status to BUSY.
3198 *
3199 * Return: 0 upon success or -EINVAL if the sense buffer is too small.
3200 */
3201 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
3202 {
3203 const struct sense_info *si;
3204 u8 *buffer = cmd->sense_buffer;
3205 int r = (__force int)reason;
3206 u8 key, asc, ascq;
3207 bool desc_format = target_sense_desc_format(cmd->se_dev);
3208
3209 if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
3210 si = &sense_info_table[r];
3211 else
3212 si = &sense_info_table[(__force int)
3213 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3214
3215 key = si->key;
3216 if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
3217 if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc,
3218 &ascq)) {
3219 cmd->scsi_status = SAM_STAT_BUSY;
3220 return;
3221 }
3222 } else if (si->asc == 0) {
3223 WARN_ON_ONCE(cmd->scsi_asc == 0);
3224 asc = cmd->scsi_asc;
3225 ascq = cmd->scsi_ascq;
3226 } else {
3227 asc = si->asc;
3228 ascq = si->ascq;
3229 }
3230
3231 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
3232 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
3233 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
3234 scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
3235 if (si->add_sector_info)
3236 WARN_ON_ONCE(scsi_set_sense_information(buffer,
3237 cmd->scsi_sense_length,
3238 cmd->bad_sector) < 0);
3239 }
3240
3241 int
3242 transport_send_check_condition_and_sense(struct se_cmd *cmd,
3243 sense_reason_t reason, int from_transport)
3244 {
3245 unsigned long flags;
3246
3247 spin_lock_irqsave(&cmd->t_state_lock, flags);
3248 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
3249 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3250 return 0;
3251 }
3252 cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
3253 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3254
3255 if (!from_transport)
3256 translate_sense_reason(cmd, reason);
3257
3258 trace_target_cmd_complete(cmd);
3259 return cmd->se_tfo->queue_status(cmd);
3260 }
3261 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
3262
3263 static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
3264 __releases(&cmd->t_state_lock)
3265 __acquires(&cmd->t_state_lock)
3266 {
3267 int ret;
3268
3269 assert_spin_locked(&cmd->t_state_lock);
3270 WARN_ON_ONCE(!irqs_disabled());
3271
3272 if (!(cmd->transport_state & CMD_T_ABORTED))
3273 return 0;
3274 /*
3275 * If cmd has been aborted but either no status is to be sent or it has
3276 * already been sent, just return
3277 */
3278 if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
3279 if (send_status)
3280 cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3281 return 1;
3282 }
3283
3284 pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
3285 " 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);
3286
3287 cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
3288 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3289 trace_target_cmd_complete(cmd);
3290
3291 spin_unlock_irq(&cmd->t_state_lock);
3292 ret = cmd->se_tfo->queue_status(cmd);
3293 if (ret)
3294 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
3295 spin_lock_irq(&cmd->t_state_lock);
3296
3297 return 1;
3298 }
3299
3300 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
3301 {
3302 int ret;
3303
3304 spin_lock_irq(&cmd->t_state_lock);
3305 ret = __transport_check_aborted_status(cmd, send_status);
3306 spin_unlock_irq(&cmd->t_state_lock);
3307
3308 return ret;
3309 }
3310 EXPORT_SYMBOL(transport_check_aborted_status);
3311
3312 void transport_send_task_abort(struct se_cmd *cmd)
3313 {
3314 unsigned long flags;
3315 int ret;
3316
3317 spin_lock_irqsave(&cmd->t_state_lock, flags);
3318 if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
3319 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3320 return;
3321 }
3322 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3323
3324 /*
3325 * If there are still expected incoming fabric WRITEs, we wait
3326 * until until they have completed before sending a TASK_ABORTED
3327 * response. This response with TASK_ABORTED status will be
3328 * queued back to fabric module by transport_check_aborted_status().
3329 */
3330 if (cmd->data_direction == DMA_TO_DEVICE) {
3331 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
3332 spin_lock_irqsave(&cmd->t_state_lock, flags);
3333 if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) {
3334 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3335 goto send_abort;
3336 }
3337 cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3338 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3339 return;
3340 }
3341 }
3342 send_abort:
3343 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3344
3345 transport_lun_remove_cmd(cmd);
3346
3347 pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
3348 cmd->t_task_cdb[0], cmd->tag);
3349
3350 trace_target_cmd_complete(cmd);
3351 ret = cmd->se_tfo->queue_status(cmd);
3352 if (ret)
3353 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
3354 }
3355
3356 static void target_tmr_work(struct work_struct *work)
3357 {
3358 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3359 struct se_device *dev = cmd->se_dev;
3360 struct se_tmr_req *tmr = cmd->se_tmr_req;
3361 unsigned long flags;
3362 int ret;
3363
3364 spin_lock_irqsave(&cmd->t_state_lock, flags);
3365 if (cmd->transport_state & CMD_T_ABORTED) {
3366 tmr->response = TMR_FUNCTION_REJECTED;
3367 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3368 goto check_stop;
3369 }
3370 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3371
3372 switch (tmr->function) {
3373 case TMR_ABORT_TASK:
3374 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3375 break;
3376 case TMR_ABORT_TASK_SET:
3377 case TMR_CLEAR_ACA:
3378 case TMR_CLEAR_TASK_SET:
3379 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3380 break;
3381 case TMR_LUN_RESET:
3382 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3383 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3384 TMR_FUNCTION_REJECTED;
3385 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3386 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3387 cmd->orig_fe_lun, 0x29,
3388 ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3389 }
3390 break;
3391 case TMR_TARGET_WARM_RESET:
3392 tmr->response = TMR_FUNCTION_REJECTED;
3393 break;
3394 case TMR_TARGET_COLD_RESET:
3395 tmr->response = TMR_FUNCTION_REJECTED;
3396 break;
3397 default:
3398 pr_err("Unknown TMR function: 0x%02x.\n",
3399 tmr->function);
3400 tmr->response = TMR_FUNCTION_REJECTED;
3401 break;
3402 }
3403
3404 spin_lock_irqsave(&cmd->t_state_lock, flags);
3405 if (cmd->transport_state & CMD_T_ABORTED) {
3406 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3407 goto check_stop;
3408 }
3409 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3410
3411 cmd->se_tfo->queue_tm_rsp(cmd);
3412
3413 check_stop:
3414 transport_lun_remove_cmd(cmd);
3415 transport_cmd_check_stop_to_fabric(cmd);
3416 }
3417
3418 int transport_generic_handle_tmr(
3419 struct se_cmd *cmd)
3420 {
3421 unsigned long flags;
3422 bool aborted = false;
3423
3424 spin_lock_irqsave(&cmd->t_state_lock, flags);
3425 if (cmd->transport_state & CMD_T_ABORTED) {
3426 aborted = true;
3427 } else {
3428 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3429 cmd->transport_state |= CMD_T_ACTIVE;
3430 }
3431 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3432
3433 if (aborted) {
3434 pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d"
3435 "ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function,
3436 cmd->se_tmr_req->ref_task_tag, cmd->tag);
3437 transport_lun_remove_cmd(cmd);
3438 transport_cmd_check_stop_to_fabric(cmd);
3439 return 0;
3440 }
3441
3442 INIT_WORK(&cmd->work, target_tmr_work);
3443 queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3444 return 0;
3445 }
3446 EXPORT_SYMBOL(transport_generic_handle_tmr);
3447
3448 bool
3449 target_check_wce(struct se_device *dev)
3450 {
3451 bool wce = false;
3452
3453 if (dev->transport->get_write_cache)
3454 wce = dev->transport->get_write_cache(dev);
3455 else if (dev->dev_attrib.emulate_write_cache > 0)
3456 wce = true;
3457
3458 return wce;
3459 }
3460
3461 bool
3462 target_check_fua(struct se_device *dev)
3463 {
3464 return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3465 }
Linux with added FPC-III support