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