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