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Merge branch 'net-fix-netpoll-crash-with-bnxt'
[mirror_ubuntu-jammy-kernel.git] / drivers / target / target_core_transport.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3 * Filename: target_core_transport.c
4 *
5 * This file contains the Generic Target Engine Core.
6 *
7 * (c) Copyright 2002-2013 Datera, Inc.
8 *
9 * Nicholas A. Bellinger <nab@kernel.org>
10 *
11 ******************************************************************************/
12
13 #include <linux/net.h>
14 #include <linux/delay.h>
15 #include <linux/string.h>
16 #include <linux/timer.h>
17 #include <linux/slab.h>
18 #include <linux/spinlock.h>
19 #include <linux/kthread.h>
20 #include <linux/in.h>
21 #include <linux/cdrom.h>
22 #include <linux/module.h>
23 #include <linux/ratelimit.h>
24 #include <linux/vmalloc.h>
25 #include <asm/unaligned.h>
26 #include <net/sock.h>
27 #include <net/tcp.h>
28 #include <scsi/scsi_proto.h>
29 #include <scsi/scsi_common.h>
30
31 #include <target/target_core_base.h>
32 #include <target/target_core_backend.h>
33 #include <target/target_core_fabric.h>
34
35 #include "target_core_internal.h"
36 #include "target_core_alua.h"
37 #include "target_core_pr.h"
38 #include "target_core_ua.h"
39
40 #define CREATE_TRACE_POINTS
41 #include <trace/events/target.h>
42
43 static struct workqueue_struct *target_completion_wq;
44 static struct kmem_cache *se_sess_cache;
45 struct kmem_cache *se_ua_cache;
46 struct kmem_cache *t10_pr_reg_cache;
47 struct kmem_cache *t10_alua_lu_gp_cache;
48 struct kmem_cache *t10_alua_lu_gp_mem_cache;
49 struct kmem_cache *t10_alua_tg_pt_gp_cache;
50 struct kmem_cache *t10_alua_lba_map_cache;
51 struct kmem_cache *t10_alua_lba_map_mem_cache;
52
53 static void transport_complete_task_attr(struct se_cmd *cmd);
54 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason);
55 static void transport_handle_queue_full(struct se_cmd *cmd,
56 struct se_device *dev, int err, bool write_pending);
57 static void target_complete_ok_work(struct work_struct *work);
58
59 int init_se_kmem_caches(void)
60 {
61 se_sess_cache = kmem_cache_create("se_sess_cache",
62 sizeof(struct se_session), __alignof__(struct se_session),
63 0, NULL);
64 if (!se_sess_cache) {
65 pr_err("kmem_cache_create() for struct se_session"
66 " failed\n");
67 goto out;
68 }
69 se_ua_cache = kmem_cache_create("se_ua_cache",
70 sizeof(struct se_ua), __alignof__(struct se_ua),
71 0, NULL);
72 if (!se_ua_cache) {
73 pr_err("kmem_cache_create() for struct se_ua failed\n");
74 goto out_free_sess_cache;
75 }
76 t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
77 sizeof(struct t10_pr_registration),
78 __alignof__(struct t10_pr_registration), 0, NULL);
79 if (!t10_pr_reg_cache) {
80 pr_err("kmem_cache_create() for struct t10_pr_registration"
81 " failed\n");
82 goto out_free_ua_cache;
83 }
84 t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
85 sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
86 0, NULL);
87 if (!t10_alua_lu_gp_cache) {
88 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
89 " failed\n");
90 goto out_free_pr_reg_cache;
91 }
92 t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
93 sizeof(struct t10_alua_lu_gp_member),
94 __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
95 if (!t10_alua_lu_gp_mem_cache) {
96 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
97 "cache failed\n");
98 goto out_free_lu_gp_cache;
99 }
100 t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
101 sizeof(struct t10_alua_tg_pt_gp),
102 __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
103 if (!t10_alua_tg_pt_gp_cache) {
104 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
105 "cache failed\n");
106 goto out_free_lu_gp_mem_cache;
107 }
108 t10_alua_lba_map_cache = kmem_cache_create(
109 "t10_alua_lba_map_cache",
110 sizeof(struct t10_alua_lba_map),
111 __alignof__(struct t10_alua_lba_map), 0, NULL);
112 if (!t10_alua_lba_map_cache) {
113 pr_err("kmem_cache_create() for t10_alua_lba_map_"
114 "cache failed\n");
115 goto out_free_tg_pt_gp_cache;
116 }
117 t10_alua_lba_map_mem_cache = kmem_cache_create(
118 "t10_alua_lba_map_mem_cache",
119 sizeof(struct t10_alua_lba_map_member),
120 __alignof__(struct t10_alua_lba_map_member), 0, NULL);
121 if (!t10_alua_lba_map_mem_cache) {
122 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
123 "cache failed\n");
124 goto out_free_lba_map_cache;
125 }
126
127 target_completion_wq = alloc_workqueue("target_completion",
128 WQ_MEM_RECLAIM, 0);
129 if (!target_completion_wq)
130 goto out_free_lba_map_mem_cache;
131
132 return 0;
133
134 out_free_lba_map_mem_cache:
135 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
136 out_free_lba_map_cache:
137 kmem_cache_destroy(t10_alua_lba_map_cache);
138 out_free_tg_pt_gp_cache:
139 kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
140 out_free_lu_gp_mem_cache:
141 kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
142 out_free_lu_gp_cache:
143 kmem_cache_destroy(t10_alua_lu_gp_cache);
144 out_free_pr_reg_cache:
145 kmem_cache_destroy(t10_pr_reg_cache);
146 out_free_ua_cache:
147 kmem_cache_destroy(se_ua_cache);
148 out_free_sess_cache:
149 kmem_cache_destroy(se_sess_cache);
150 out:
151 return -ENOMEM;
152 }
153
154 void release_se_kmem_caches(void)
155 {
156 destroy_workqueue(target_completion_wq);
157 kmem_cache_destroy(se_sess_cache);
158 kmem_cache_destroy(se_ua_cache);
159 kmem_cache_destroy(t10_pr_reg_cache);
160 kmem_cache_destroy(t10_alua_lu_gp_cache);
161 kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
162 kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
163 kmem_cache_destroy(t10_alua_lba_map_cache);
164 kmem_cache_destroy(t10_alua_lba_map_mem_cache);
165 }
166
167 /* This code ensures unique mib indexes are handed out. */
168 static DEFINE_SPINLOCK(scsi_mib_index_lock);
169 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
170
171 /*
172 * Allocate a new row index for the entry type specified
173 */
174 u32 scsi_get_new_index(scsi_index_t type)
175 {
176 u32 new_index;
177
178 BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
179
180 spin_lock(&scsi_mib_index_lock);
181 new_index = ++scsi_mib_index[type];
182 spin_unlock(&scsi_mib_index_lock);
183
184 return new_index;
185 }
186
187 void transport_subsystem_check_init(void)
188 {
189 int ret;
190 static int sub_api_initialized;
191
192 if (sub_api_initialized)
193 return;
194
195 ret = IS_ENABLED(CONFIG_TCM_IBLOCK) && request_module("target_core_iblock");
196 if (ret != 0)
197 pr_err("Unable to load target_core_iblock\n");
198
199 ret = IS_ENABLED(CONFIG_TCM_FILEIO) && request_module("target_core_file");
200 if (ret != 0)
201 pr_err("Unable to load target_core_file\n");
202
203 ret = IS_ENABLED(CONFIG_TCM_PSCSI) && request_module("target_core_pscsi");
204 if (ret != 0)
205 pr_err("Unable to load target_core_pscsi\n");
206
207 ret = IS_ENABLED(CONFIG_TCM_USER2) && request_module("target_core_user");
208 if (ret != 0)
209 pr_err("Unable to load target_core_user\n");
210
211 sub_api_initialized = 1;
212 }
213
214 static void target_release_sess_cmd_refcnt(struct percpu_ref *ref)
215 {
216 struct se_session *sess = container_of(ref, typeof(*sess), cmd_count);
217
218 wake_up(&sess->cmd_list_wq);
219 }
220
221 /**
222 * transport_init_session - initialize a session object
223 * @se_sess: Session object pointer.
224 *
225 * The caller must have zero-initialized @se_sess before calling this function.
226 */
227 int transport_init_session(struct se_session *se_sess)
228 {
229 INIT_LIST_HEAD(&se_sess->sess_list);
230 INIT_LIST_HEAD(&se_sess->sess_acl_list);
231 INIT_LIST_HEAD(&se_sess->sess_cmd_list);
232 spin_lock_init(&se_sess->sess_cmd_lock);
233 init_waitqueue_head(&se_sess->cmd_list_wq);
234 return percpu_ref_init(&se_sess->cmd_count,
235 target_release_sess_cmd_refcnt, 0, GFP_KERNEL);
236 }
237 EXPORT_SYMBOL(transport_init_session);
238
239 void transport_uninit_session(struct se_session *se_sess)
240 {
241 percpu_ref_exit(&se_sess->cmd_count);
242 }
243
244 /**
245 * transport_alloc_session - allocate a session object and initialize it
246 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
247 */
248 struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
249 {
250 struct se_session *se_sess;
251 int ret;
252
253 se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
254 if (!se_sess) {
255 pr_err("Unable to allocate struct se_session from"
256 " se_sess_cache\n");
257 return ERR_PTR(-ENOMEM);
258 }
259 ret = transport_init_session(se_sess);
260 if (ret < 0) {
261 kmem_cache_free(se_sess_cache, se_sess);
262 return ERR_PTR(ret);
263 }
264 se_sess->sup_prot_ops = sup_prot_ops;
265
266 return se_sess;
267 }
268 EXPORT_SYMBOL(transport_alloc_session);
269
270 /**
271 * transport_alloc_session_tags - allocate target driver private data
272 * @se_sess: Session pointer.
273 * @tag_num: Maximum number of in-flight commands between initiator and target.
274 * @tag_size: Size in bytes of the private data a target driver associates with
275 * each command.
276 */
277 int transport_alloc_session_tags(struct se_session *se_sess,
278 unsigned int tag_num, unsigned int tag_size)
279 {
280 int rc;
281
282 se_sess->sess_cmd_map = kvcalloc(tag_size, tag_num,
283 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
284 if (!se_sess->sess_cmd_map) {
285 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
286 return -ENOMEM;
287 }
288
289 rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
290 false, GFP_KERNEL, NUMA_NO_NODE);
291 if (rc < 0) {
292 pr_err("Unable to init se_sess->sess_tag_pool,"
293 " tag_num: %u\n", tag_num);
294 kvfree(se_sess->sess_cmd_map);
295 se_sess->sess_cmd_map = NULL;
296 return -ENOMEM;
297 }
298
299 return 0;
300 }
301 EXPORT_SYMBOL(transport_alloc_session_tags);
302
303 /**
304 * transport_init_session_tags - allocate a session and target driver private data
305 * @tag_num: Maximum number of in-flight commands between initiator and target.
306 * @tag_size: Size in bytes of the private data a target driver associates with
307 * each command.
308 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
309 */
310 static struct se_session *
311 transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
312 enum target_prot_op sup_prot_ops)
313 {
314 struct se_session *se_sess;
315 int rc;
316
317 if (tag_num != 0 && !tag_size) {
318 pr_err("init_session_tags called with percpu-ida tag_num:"
319 " %u, but zero tag_size\n", tag_num);
320 return ERR_PTR(-EINVAL);
321 }
322 if (!tag_num && tag_size) {
323 pr_err("init_session_tags called with percpu-ida tag_size:"
324 " %u, but zero tag_num\n", tag_size);
325 return ERR_PTR(-EINVAL);
326 }
327
328 se_sess = transport_alloc_session(sup_prot_ops);
329 if (IS_ERR(se_sess))
330 return se_sess;
331
332 rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
333 if (rc < 0) {
334 transport_free_session(se_sess);
335 return ERR_PTR(-ENOMEM);
336 }
337
338 return se_sess;
339 }
340
341 /*
342 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
343 */
344 void __transport_register_session(
345 struct se_portal_group *se_tpg,
346 struct se_node_acl *se_nacl,
347 struct se_session *se_sess,
348 void *fabric_sess_ptr)
349 {
350 const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
351 unsigned char buf[PR_REG_ISID_LEN];
352 unsigned long flags;
353
354 se_sess->se_tpg = se_tpg;
355 se_sess->fabric_sess_ptr = fabric_sess_ptr;
356 /*
357 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
358 *
359 * Only set for struct se_session's that will actually be moving I/O.
360 * eg: *NOT* discovery sessions.
361 */
362 if (se_nacl) {
363 /*
364 *
365 * Determine if fabric allows for T10-PI feature bits exposed to
366 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
367 *
368 * If so, then always save prot_type on a per se_node_acl node
369 * basis and re-instate the previous sess_prot_type to avoid
370 * disabling PI from below any previously initiator side
371 * registered LUNs.
372 */
373 if (se_nacl->saved_prot_type)
374 se_sess->sess_prot_type = se_nacl->saved_prot_type;
375 else if (tfo->tpg_check_prot_fabric_only)
376 se_sess->sess_prot_type = se_nacl->saved_prot_type =
377 tfo->tpg_check_prot_fabric_only(se_tpg);
378 /*
379 * If the fabric module supports an ISID based TransportID,
380 * save this value in binary from the fabric I_T Nexus now.
381 */
382 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
383 memset(&buf[0], 0, PR_REG_ISID_LEN);
384 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
385 &buf[0], PR_REG_ISID_LEN);
386 se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
387 }
388
389 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
390 /*
391 * The se_nacl->nacl_sess pointer will be set to the
392 * last active I_T Nexus for each struct se_node_acl.
393 */
394 se_nacl->nacl_sess = se_sess;
395
396 list_add_tail(&se_sess->sess_acl_list,
397 &se_nacl->acl_sess_list);
398 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
399 }
400 list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
401
402 pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
403 se_tpg->se_tpg_tfo->fabric_name, se_sess->fabric_sess_ptr);
404 }
405 EXPORT_SYMBOL(__transport_register_session);
406
407 void transport_register_session(
408 struct se_portal_group *se_tpg,
409 struct se_node_acl *se_nacl,
410 struct se_session *se_sess,
411 void *fabric_sess_ptr)
412 {
413 unsigned long flags;
414
415 spin_lock_irqsave(&se_tpg->session_lock, flags);
416 __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
417 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
418 }
419 EXPORT_SYMBOL(transport_register_session);
420
421 struct se_session *
422 target_setup_session(struct se_portal_group *tpg,
423 unsigned int tag_num, unsigned int tag_size,
424 enum target_prot_op prot_op,
425 const char *initiatorname, void *private,
426 int (*callback)(struct se_portal_group *,
427 struct se_session *, void *))
428 {
429 struct se_session *sess;
430
431 /*
432 * If the fabric driver is using percpu-ida based pre allocation
433 * of I/O descriptor tags, go ahead and perform that setup now..
434 */
435 if (tag_num != 0)
436 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
437 else
438 sess = transport_alloc_session(prot_op);
439
440 if (IS_ERR(sess))
441 return sess;
442
443 sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
444 (unsigned char *)initiatorname);
445 if (!sess->se_node_acl) {
446 transport_free_session(sess);
447 return ERR_PTR(-EACCES);
448 }
449 /*
450 * Go ahead and perform any remaining fabric setup that is
451 * required before transport_register_session().
452 */
453 if (callback != NULL) {
454 int rc = callback(tpg, sess, private);
455 if (rc) {
456 transport_free_session(sess);
457 return ERR_PTR(rc);
458 }
459 }
460
461 transport_register_session(tpg, sess->se_node_acl, sess, private);
462 return sess;
463 }
464 EXPORT_SYMBOL(target_setup_session);
465
466 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
467 {
468 struct se_session *se_sess;
469 ssize_t len = 0;
470
471 spin_lock_bh(&se_tpg->session_lock);
472 list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
473 if (!se_sess->se_node_acl)
474 continue;
475 if (!se_sess->se_node_acl->dynamic_node_acl)
476 continue;
477 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
478 break;
479
480 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
481 se_sess->se_node_acl->initiatorname);
482 len += 1; /* Include NULL terminator */
483 }
484 spin_unlock_bh(&se_tpg->session_lock);
485
486 return len;
487 }
488 EXPORT_SYMBOL(target_show_dynamic_sessions);
489
490 static void target_complete_nacl(struct kref *kref)
491 {
492 struct se_node_acl *nacl = container_of(kref,
493 struct se_node_acl, acl_kref);
494 struct se_portal_group *se_tpg = nacl->se_tpg;
495
496 if (!nacl->dynamic_stop) {
497 complete(&nacl->acl_free_comp);
498 return;
499 }
500
501 mutex_lock(&se_tpg->acl_node_mutex);
502 list_del_init(&nacl->acl_list);
503 mutex_unlock(&se_tpg->acl_node_mutex);
504
505 core_tpg_wait_for_nacl_pr_ref(nacl);
506 core_free_device_list_for_node(nacl, se_tpg);
507 kfree(nacl);
508 }
509
510 void target_put_nacl(struct se_node_acl *nacl)
511 {
512 kref_put(&nacl->acl_kref, target_complete_nacl);
513 }
514 EXPORT_SYMBOL(target_put_nacl);
515
516 void transport_deregister_session_configfs(struct se_session *se_sess)
517 {
518 struct se_node_acl *se_nacl;
519 unsigned long flags;
520 /*
521 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
522 */
523 se_nacl = se_sess->se_node_acl;
524 if (se_nacl) {
525 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
526 if (!list_empty(&se_sess->sess_acl_list))
527 list_del_init(&se_sess->sess_acl_list);
528 /*
529 * If the session list is empty, then clear the pointer.
530 * Otherwise, set the struct se_session pointer from the tail
531 * element of the per struct se_node_acl active session list.
532 */
533 if (list_empty(&se_nacl->acl_sess_list))
534 se_nacl->nacl_sess = NULL;
535 else {
536 se_nacl->nacl_sess = container_of(
537 se_nacl->acl_sess_list.prev,
538 struct se_session, sess_acl_list);
539 }
540 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
541 }
542 }
543 EXPORT_SYMBOL(transport_deregister_session_configfs);
544
545 void transport_free_session(struct se_session *se_sess)
546 {
547 struct se_node_acl *se_nacl = se_sess->se_node_acl;
548
549 /*
550 * Drop the se_node_acl->nacl_kref obtained from within
551 * core_tpg_get_initiator_node_acl().
552 */
553 if (se_nacl) {
554 struct se_portal_group *se_tpg = se_nacl->se_tpg;
555 const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
556 unsigned long flags;
557
558 se_sess->se_node_acl = NULL;
559
560 /*
561 * Also determine if we need to drop the extra ->cmd_kref if
562 * it had been previously dynamically generated, and
563 * the endpoint is not caching dynamic ACLs.
564 */
565 mutex_lock(&se_tpg->acl_node_mutex);
566 if (se_nacl->dynamic_node_acl &&
567 !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
568 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
569 if (list_empty(&se_nacl->acl_sess_list))
570 se_nacl->dynamic_stop = true;
571 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
572
573 if (se_nacl->dynamic_stop)
574 list_del_init(&se_nacl->acl_list);
575 }
576 mutex_unlock(&se_tpg->acl_node_mutex);
577
578 if (se_nacl->dynamic_stop)
579 target_put_nacl(se_nacl);
580
581 target_put_nacl(se_nacl);
582 }
583 if (se_sess->sess_cmd_map) {
584 sbitmap_queue_free(&se_sess->sess_tag_pool);
585 kvfree(se_sess->sess_cmd_map);
586 }
587 transport_uninit_session(se_sess);
588 kmem_cache_free(se_sess_cache, se_sess);
589 }
590 EXPORT_SYMBOL(transport_free_session);
591
592 static int target_release_res(struct se_device *dev, void *data)
593 {
594 struct se_session *sess = data;
595
596 if (dev->reservation_holder == sess)
597 target_release_reservation(dev);
598 return 0;
599 }
600
601 void transport_deregister_session(struct se_session *se_sess)
602 {
603 struct se_portal_group *se_tpg = se_sess->se_tpg;
604 unsigned long flags;
605
606 if (!se_tpg) {
607 transport_free_session(se_sess);
608 return;
609 }
610
611 spin_lock_irqsave(&se_tpg->session_lock, flags);
612 list_del(&se_sess->sess_list);
613 se_sess->se_tpg = NULL;
614 se_sess->fabric_sess_ptr = NULL;
615 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
616
617 /*
618 * Since the session is being removed, release SPC-2
619 * reservations held by the session that is disappearing.
620 */
621 target_for_each_device(target_release_res, se_sess);
622
623 pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
624 se_tpg->se_tpg_tfo->fabric_name);
625 /*
626 * If last kref is dropping now for an explicit NodeACL, awake sleeping
627 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
628 * removal context from within transport_free_session() code.
629 *
630 * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
631 * to release all remaining generate_node_acl=1 created ACL resources.
632 */
633
634 transport_free_session(se_sess);
635 }
636 EXPORT_SYMBOL(transport_deregister_session);
637
638 void target_remove_session(struct se_session *se_sess)
639 {
640 transport_deregister_session_configfs(se_sess);
641 transport_deregister_session(se_sess);
642 }
643 EXPORT_SYMBOL(target_remove_session);
644
645 static void target_remove_from_state_list(struct se_cmd *cmd)
646 {
647 struct se_device *dev = cmd->se_dev;
648 unsigned long flags;
649
650 if (!dev)
651 return;
652
653 spin_lock_irqsave(&dev->execute_task_lock, flags);
654 if (cmd->state_active) {
655 list_del(&cmd->state_list);
656 cmd->state_active = false;
657 }
658 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
659 }
660
661 /*
662 * This function is called by the target core after the target core has
663 * finished processing a SCSI command or SCSI TMF. Both the regular command
664 * processing code and the code for aborting commands can call this
665 * function. CMD_T_STOP is set if and only if another thread is waiting
666 * inside transport_wait_for_tasks() for t_transport_stop_comp.
667 */
668 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
669 {
670 unsigned long flags;
671
672 target_remove_from_state_list(cmd);
673
674 /*
675 * Clear struct se_cmd->se_lun before the handoff to FE.
676 */
677 cmd->se_lun = NULL;
678
679 spin_lock_irqsave(&cmd->t_state_lock, flags);
680 /*
681 * Determine if frontend context caller is requesting the stopping of
682 * this command for frontend exceptions.
683 */
684 if (cmd->transport_state & CMD_T_STOP) {
685 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
686 __func__, __LINE__, cmd->tag);
687
688 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
689
690 complete_all(&cmd->t_transport_stop_comp);
691 return 1;
692 }
693 cmd->transport_state &= ~CMD_T_ACTIVE;
694 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
695
696 /*
697 * Some fabric modules like tcm_loop can release their internally
698 * allocated I/O reference and struct se_cmd now.
699 *
700 * Fabric modules are expected to return '1' here if the se_cmd being
701 * passed is released at this point, or zero if not being released.
702 */
703 return cmd->se_tfo->check_stop_free(cmd);
704 }
705
706 static void transport_lun_remove_cmd(struct se_cmd *cmd)
707 {
708 struct se_lun *lun = cmd->se_lun;
709
710 if (!lun)
711 return;
712
713 if (cmpxchg(&cmd->lun_ref_active, true, false))
714 percpu_ref_put(&lun->lun_ref);
715 }
716
717 static void target_complete_failure_work(struct work_struct *work)
718 {
719 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
720
721 transport_generic_request_failure(cmd,
722 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
723 }
724
725 /*
726 * Used when asking transport to copy Sense Data from the underlying
727 * Linux/SCSI struct scsi_cmnd
728 */
729 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
730 {
731 struct se_device *dev = cmd->se_dev;
732
733 WARN_ON(!cmd->se_lun);
734
735 if (!dev)
736 return NULL;
737
738 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
739 return NULL;
740
741 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
742
743 pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
744 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
745 return cmd->sense_buffer;
746 }
747
748 void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
749 {
750 unsigned char *cmd_sense_buf;
751 unsigned long flags;
752
753 spin_lock_irqsave(&cmd->t_state_lock, flags);
754 cmd_sense_buf = transport_get_sense_buffer(cmd);
755 if (!cmd_sense_buf) {
756 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
757 return;
758 }
759
760 cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
761 memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
762 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
763 }
764 EXPORT_SYMBOL(transport_copy_sense_to_cmd);
765
766 static void target_handle_abort(struct se_cmd *cmd)
767 {
768 bool tas = cmd->transport_state & CMD_T_TAS;
769 bool ack_kref = cmd->se_cmd_flags & SCF_ACK_KREF;
770 int ret;
771
772 pr_debug("tag %#llx: send_abort_response = %d\n", cmd->tag, tas);
773
774 if (tas) {
775 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
776 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
777 pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
778 cmd->t_task_cdb[0], cmd->tag);
779 trace_target_cmd_complete(cmd);
780 ret = cmd->se_tfo->queue_status(cmd);
781 if (ret) {
782 transport_handle_queue_full(cmd, cmd->se_dev,
783 ret, false);
784 return;
785 }
786 } else {
787 cmd->se_tmr_req->response = TMR_FUNCTION_REJECTED;
788 cmd->se_tfo->queue_tm_rsp(cmd);
789 }
790 } else {
791 /*
792 * Allow the fabric driver to unmap any resources before
793 * releasing the descriptor via TFO->release_cmd().
794 */
795 cmd->se_tfo->aborted_task(cmd);
796 if (ack_kref)
797 WARN_ON_ONCE(target_put_sess_cmd(cmd) != 0);
798 /*
799 * To do: establish a unit attention condition on the I_T
800 * nexus associated with cmd. See also the paragraph "Aborting
801 * commands" in SAM.
802 */
803 }
804
805 WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0);
806
807 transport_lun_remove_cmd(cmd);
808
809 transport_cmd_check_stop_to_fabric(cmd);
810 }
811
812 static void target_abort_work(struct work_struct *work)
813 {
814 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
815
816 target_handle_abort(cmd);
817 }
818
819 static bool target_cmd_interrupted(struct se_cmd *cmd)
820 {
821 int post_ret;
822
823 if (cmd->transport_state & CMD_T_ABORTED) {
824 if (cmd->transport_complete_callback)
825 cmd->transport_complete_callback(cmd, false, &post_ret);
826 INIT_WORK(&cmd->work, target_abort_work);
827 queue_work(target_completion_wq, &cmd->work);
828 return true;
829 } else if (cmd->transport_state & CMD_T_STOP) {
830 if (cmd->transport_complete_callback)
831 cmd->transport_complete_callback(cmd, false, &post_ret);
832 complete_all(&cmd->t_transport_stop_comp);
833 return true;
834 }
835
836 return false;
837 }
838
839 /* May be called from interrupt context so must not sleep. */
840 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
841 {
842 int success;
843 unsigned long flags;
844
845 if (target_cmd_interrupted(cmd))
846 return;
847
848 cmd->scsi_status = scsi_status;
849
850 spin_lock_irqsave(&cmd->t_state_lock, flags);
851 switch (cmd->scsi_status) {
852 case SAM_STAT_CHECK_CONDITION:
853 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
854 success = 1;
855 else
856 success = 0;
857 break;
858 default:
859 success = 1;
860 break;
861 }
862
863 cmd->t_state = TRANSPORT_COMPLETE;
864 cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
865 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
866
867 INIT_WORK(&cmd->work, success ? target_complete_ok_work :
868 target_complete_failure_work);
869 if (cmd->se_cmd_flags & SCF_USE_CPUID)
870 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
871 else
872 queue_work(target_completion_wq, &cmd->work);
873 }
874 EXPORT_SYMBOL(target_complete_cmd);
875
876 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
877 {
878 if ((scsi_status == SAM_STAT_GOOD ||
879 cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
880 length < cmd->data_length) {
881 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
882 cmd->residual_count += cmd->data_length - length;
883 } else {
884 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
885 cmd->residual_count = cmd->data_length - length;
886 }
887
888 cmd->data_length = length;
889 }
890
891 target_complete_cmd(cmd, scsi_status);
892 }
893 EXPORT_SYMBOL(target_complete_cmd_with_length);
894
895 static void target_add_to_state_list(struct se_cmd *cmd)
896 {
897 struct se_device *dev = cmd->se_dev;
898 unsigned long flags;
899
900 spin_lock_irqsave(&dev->execute_task_lock, flags);
901 if (!cmd->state_active) {
902 list_add_tail(&cmd->state_list, &dev->state_list);
903 cmd->state_active = true;
904 }
905 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
906 }
907
908 /*
909 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
910 */
911 static void transport_write_pending_qf(struct se_cmd *cmd);
912 static void transport_complete_qf(struct se_cmd *cmd);
913
914 void target_qf_do_work(struct work_struct *work)
915 {
916 struct se_device *dev = container_of(work, struct se_device,
917 qf_work_queue);
918 LIST_HEAD(qf_cmd_list);
919 struct se_cmd *cmd, *cmd_tmp;
920
921 spin_lock_irq(&dev->qf_cmd_lock);
922 list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
923 spin_unlock_irq(&dev->qf_cmd_lock);
924
925 list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
926 list_del(&cmd->se_qf_node);
927 atomic_dec_mb(&dev->dev_qf_count);
928
929 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
930 " context: %s\n", cmd->se_tfo->fabric_name, cmd,
931 (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
932 (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
933 : "UNKNOWN");
934
935 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
936 transport_write_pending_qf(cmd);
937 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
938 cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
939 transport_complete_qf(cmd);
940 }
941 }
942
943 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
944 {
945 switch (cmd->data_direction) {
946 case DMA_NONE:
947 return "NONE";
948 case DMA_FROM_DEVICE:
949 return "READ";
950 case DMA_TO_DEVICE:
951 return "WRITE";
952 case DMA_BIDIRECTIONAL:
953 return "BIDI";
954 default:
955 break;
956 }
957
958 return "UNKNOWN";
959 }
960
961 void transport_dump_dev_state(
962 struct se_device *dev,
963 char *b,
964 int *bl)
965 {
966 *bl += sprintf(b + *bl, "Status: ");
967 if (dev->export_count)
968 *bl += sprintf(b + *bl, "ACTIVATED");
969 else
970 *bl += sprintf(b + *bl, "DEACTIVATED");
971
972 *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
973 *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
974 dev->dev_attrib.block_size,
975 dev->dev_attrib.hw_max_sectors);
976 *bl += sprintf(b + *bl, " ");
977 }
978
979 void transport_dump_vpd_proto_id(
980 struct t10_vpd *vpd,
981 unsigned char *p_buf,
982 int p_buf_len)
983 {
984 unsigned char buf[VPD_TMP_BUF_SIZE];
985 int len;
986
987 memset(buf, 0, VPD_TMP_BUF_SIZE);
988 len = sprintf(buf, "T10 VPD Protocol Identifier: ");
989
990 switch (vpd->protocol_identifier) {
991 case 0x00:
992 sprintf(buf+len, "Fibre Channel\n");
993 break;
994 case 0x10:
995 sprintf(buf+len, "Parallel SCSI\n");
996 break;
997 case 0x20:
998 sprintf(buf+len, "SSA\n");
999 break;
1000 case 0x30:
1001 sprintf(buf+len, "IEEE 1394\n");
1002 break;
1003 case 0x40:
1004 sprintf(buf+len, "SCSI Remote Direct Memory Access"
1005 " Protocol\n");
1006 break;
1007 case 0x50:
1008 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
1009 break;
1010 case 0x60:
1011 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
1012 break;
1013 case 0x70:
1014 sprintf(buf+len, "Automation/Drive Interface Transport"
1015 " Protocol\n");
1016 break;
1017 case 0x80:
1018 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
1019 break;
1020 default:
1021 sprintf(buf+len, "Unknown 0x%02x\n",
1022 vpd->protocol_identifier);
1023 break;
1024 }
1025
1026 if (p_buf)
1027 strncpy(p_buf, buf, p_buf_len);
1028 else
1029 pr_debug("%s", buf);
1030 }
1031
1032 void
1033 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1034 {
1035 /*
1036 * Check if the Protocol Identifier Valid (PIV) bit is set..
1037 *
1038 * from spc3r23.pdf section 7.5.1
1039 */
1040 if (page_83[1] & 0x80) {
1041 vpd->protocol_identifier = (page_83[0] & 0xf0);
1042 vpd->protocol_identifier_set = 1;
1043 transport_dump_vpd_proto_id(vpd, NULL, 0);
1044 }
1045 }
1046 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1047
1048 int transport_dump_vpd_assoc(
1049 struct t10_vpd *vpd,
1050 unsigned char *p_buf,
1051 int p_buf_len)
1052 {
1053 unsigned char buf[VPD_TMP_BUF_SIZE];
1054 int ret = 0;
1055 int len;
1056
1057 memset(buf, 0, VPD_TMP_BUF_SIZE);
1058 len = sprintf(buf, "T10 VPD Identifier Association: ");
1059
1060 switch (vpd->association) {
1061 case 0x00:
1062 sprintf(buf+len, "addressed logical unit\n");
1063 break;
1064 case 0x10:
1065 sprintf(buf+len, "target port\n");
1066 break;
1067 case 0x20:
1068 sprintf(buf+len, "SCSI target device\n");
1069 break;
1070 default:
1071 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1072 ret = -EINVAL;
1073 break;
1074 }
1075
1076 if (p_buf)
1077 strncpy(p_buf, buf, p_buf_len);
1078 else
1079 pr_debug("%s", buf);
1080
1081 return ret;
1082 }
1083
1084 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1085 {
1086 /*
1087 * The VPD identification association..
1088 *
1089 * from spc3r23.pdf Section 7.6.3.1 Table 297
1090 */
1091 vpd->association = (page_83[1] & 0x30);
1092 return transport_dump_vpd_assoc(vpd, NULL, 0);
1093 }
1094 EXPORT_SYMBOL(transport_set_vpd_assoc);
1095
1096 int transport_dump_vpd_ident_type(
1097 struct t10_vpd *vpd,
1098 unsigned char *p_buf,
1099 int p_buf_len)
1100 {
1101 unsigned char buf[VPD_TMP_BUF_SIZE];
1102 int ret = 0;
1103 int len;
1104
1105 memset(buf, 0, VPD_TMP_BUF_SIZE);
1106 len = sprintf(buf, "T10 VPD Identifier Type: ");
1107
1108 switch (vpd->device_identifier_type) {
1109 case 0x00:
1110 sprintf(buf+len, "Vendor specific\n");
1111 break;
1112 case 0x01:
1113 sprintf(buf+len, "T10 Vendor ID based\n");
1114 break;
1115 case 0x02:
1116 sprintf(buf+len, "EUI-64 based\n");
1117 break;
1118 case 0x03:
1119 sprintf(buf+len, "NAA\n");
1120 break;
1121 case 0x04:
1122 sprintf(buf+len, "Relative target port identifier\n");
1123 break;
1124 case 0x08:
1125 sprintf(buf+len, "SCSI name string\n");
1126 break;
1127 default:
1128 sprintf(buf+len, "Unsupported: 0x%02x\n",
1129 vpd->device_identifier_type);
1130 ret = -EINVAL;
1131 break;
1132 }
1133
1134 if (p_buf) {
1135 if (p_buf_len < strlen(buf)+1)
1136 return -EINVAL;
1137 strncpy(p_buf, buf, p_buf_len);
1138 } else {
1139 pr_debug("%s", buf);
1140 }
1141
1142 return ret;
1143 }
1144
1145 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1146 {
1147 /*
1148 * The VPD identifier type..
1149 *
1150 * from spc3r23.pdf Section 7.6.3.1 Table 298
1151 */
1152 vpd->device_identifier_type = (page_83[1] & 0x0f);
1153 return transport_dump_vpd_ident_type(vpd, NULL, 0);
1154 }
1155 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1156
1157 int transport_dump_vpd_ident(
1158 struct t10_vpd *vpd,
1159 unsigned char *p_buf,
1160 int p_buf_len)
1161 {
1162 unsigned char buf[VPD_TMP_BUF_SIZE];
1163 int ret = 0;
1164
1165 memset(buf, 0, VPD_TMP_BUF_SIZE);
1166
1167 switch (vpd->device_identifier_code_set) {
1168 case 0x01: /* Binary */
1169 snprintf(buf, sizeof(buf),
1170 "T10 VPD Binary Device Identifier: %s\n",
1171 &vpd->device_identifier[0]);
1172 break;
1173 case 0x02: /* ASCII */
1174 snprintf(buf, sizeof(buf),
1175 "T10 VPD ASCII Device Identifier: %s\n",
1176 &vpd->device_identifier[0]);
1177 break;
1178 case 0x03: /* UTF-8 */
1179 snprintf(buf, sizeof(buf),
1180 "T10 VPD UTF-8 Device Identifier: %s\n",
1181 &vpd->device_identifier[0]);
1182 break;
1183 default:
1184 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1185 " 0x%02x", vpd->device_identifier_code_set);
1186 ret = -EINVAL;
1187 break;
1188 }
1189
1190 if (p_buf)
1191 strncpy(p_buf, buf, p_buf_len);
1192 else
1193 pr_debug("%s", buf);
1194
1195 return ret;
1196 }
1197
1198 int
1199 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1200 {
1201 static const char hex_str[] = "0123456789abcdef";
1202 int j = 0, i = 4; /* offset to start of the identifier */
1203
1204 /*
1205 * The VPD Code Set (encoding)
1206 *
1207 * from spc3r23.pdf Section 7.6.3.1 Table 296
1208 */
1209 vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1210 switch (vpd->device_identifier_code_set) {
1211 case 0x01: /* Binary */
1212 vpd->device_identifier[j++] =
1213 hex_str[vpd->device_identifier_type];
1214 while (i < (4 + page_83[3])) {
1215 vpd->device_identifier[j++] =
1216 hex_str[(page_83[i] & 0xf0) >> 4];
1217 vpd->device_identifier[j++] =
1218 hex_str[page_83[i] & 0x0f];
1219 i++;
1220 }
1221 break;
1222 case 0x02: /* ASCII */
1223 case 0x03: /* UTF-8 */
1224 while (i < (4 + page_83[3]))
1225 vpd->device_identifier[j++] = page_83[i++];
1226 break;
1227 default:
1228 break;
1229 }
1230
1231 return transport_dump_vpd_ident(vpd, NULL, 0);
1232 }
1233 EXPORT_SYMBOL(transport_set_vpd_ident);
1234
1235 static sense_reason_t
1236 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1237 unsigned int size)
1238 {
1239 u32 mtl;
1240
1241 if (!cmd->se_tfo->max_data_sg_nents)
1242 return TCM_NO_SENSE;
1243 /*
1244 * Check if fabric enforced maximum SGL entries per I/O descriptor
1245 * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT +
1246 * residual_count and reduce original cmd->data_length to maximum
1247 * length based on single PAGE_SIZE entry scatter-lists.
1248 */
1249 mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1250 if (cmd->data_length > mtl) {
1251 /*
1252 * If an existing CDB overflow is present, calculate new residual
1253 * based on CDB size minus fabric maximum transfer length.
1254 *
1255 * If an existing CDB underflow is present, calculate new residual
1256 * based on original cmd->data_length minus fabric maximum transfer
1257 * length.
1258 *
1259 * Otherwise, set the underflow residual based on cmd->data_length
1260 * minus fabric maximum transfer length.
1261 */
1262 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1263 cmd->residual_count = (size - mtl);
1264 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1265 u32 orig_dl = size + cmd->residual_count;
1266 cmd->residual_count = (orig_dl - mtl);
1267 } else {
1268 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1269 cmd->residual_count = (cmd->data_length - mtl);
1270 }
1271 cmd->data_length = mtl;
1272 /*
1273 * Reset sbc_check_prot() calculated protection payload
1274 * length based upon the new smaller MTL.
1275 */
1276 if (cmd->prot_length) {
1277 u32 sectors = (mtl / dev->dev_attrib.block_size);
1278 cmd->prot_length = dev->prot_length * sectors;
1279 }
1280 }
1281 return TCM_NO_SENSE;
1282 }
1283
1284 /**
1285 * target_cmd_size_check - Check whether there will be a residual.
1286 * @cmd: SCSI command.
1287 * @size: Data buffer size derived from CDB. The data buffer size provided by
1288 * the SCSI transport driver is available in @cmd->data_length.
1289 *
1290 * Compare the data buffer size from the CDB with the data buffer limit from the transport
1291 * header. Set @cmd->residual_count and SCF_OVERFLOW_BIT or SCF_UNDERFLOW_BIT if necessary.
1292 *
1293 * Note: target drivers set @cmd->data_length by calling transport_init_se_cmd().
1294 *
1295 * Return: TCM_NO_SENSE
1296 */
1297 sense_reason_t
1298 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1299 {
1300 struct se_device *dev = cmd->se_dev;
1301
1302 if (cmd->unknown_data_length) {
1303 cmd->data_length = size;
1304 } else if (size != cmd->data_length) {
1305 pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1306 " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1307 " 0x%02x\n", cmd->se_tfo->fabric_name,
1308 cmd->data_length, size, cmd->t_task_cdb[0]);
1309
1310 if (cmd->data_direction == DMA_TO_DEVICE) {
1311 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1312 pr_err_ratelimited("Rejecting underflow/overflow"
1313 " for WRITE data CDB\n");
1314 return TCM_INVALID_CDB_FIELD;
1315 }
1316 /*
1317 * Some fabric drivers like iscsi-target still expect to
1318 * always reject overflow writes. Reject this case until
1319 * full fabric driver level support for overflow writes
1320 * is introduced tree-wide.
1321 */
1322 if (size > cmd->data_length) {
1323 pr_err_ratelimited("Rejecting overflow for"
1324 " WRITE control CDB\n");
1325 return TCM_INVALID_CDB_FIELD;
1326 }
1327 }
1328 /*
1329 * Reject READ_* or WRITE_* with overflow/underflow for
1330 * type SCF_SCSI_DATA_CDB.
1331 */
1332 if (dev->dev_attrib.block_size != 512) {
1333 pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1334 " CDB on non 512-byte sector setup subsystem"
1335 " plugin: %s\n", dev->transport->name);
1336 /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1337 return TCM_INVALID_CDB_FIELD;
1338 }
1339 /*
1340 * For the overflow case keep the existing fabric provided
1341 * ->data_length. Otherwise for the underflow case, reset
1342 * ->data_length to the smaller SCSI expected data transfer
1343 * length.
1344 */
1345 if (size > cmd->data_length) {
1346 cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1347 cmd->residual_count = (size - cmd->data_length);
1348 } else {
1349 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1350 cmd->residual_count = (cmd->data_length - size);
1351 cmd->data_length = size;
1352 }
1353 }
1354
1355 return target_check_max_data_sg_nents(cmd, dev, size);
1356
1357 }
1358
1359 /*
1360 * Used by fabric modules containing a local struct se_cmd within their
1361 * fabric dependent per I/O descriptor.
1362 *
1363 * Preserves the value of @cmd->tag.
1364 */
1365 void transport_init_se_cmd(
1366 struct se_cmd *cmd,
1367 const struct target_core_fabric_ops *tfo,
1368 struct se_session *se_sess,
1369 u32 data_length,
1370 int data_direction,
1371 int task_attr,
1372 unsigned char *sense_buffer, u64 unpacked_lun)
1373 {
1374 INIT_LIST_HEAD(&cmd->se_delayed_node);
1375 INIT_LIST_HEAD(&cmd->se_qf_node);
1376 INIT_LIST_HEAD(&cmd->se_cmd_list);
1377 INIT_LIST_HEAD(&cmd->state_list);
1378 init_completion(&cmd->t_transport_stop_comp);
1379 cmd->free_compl = NULL;
1380 cmd->abrt_compl = NULL;
1381 spin_lock_init(&cmd->t_state_lock);
1382 INIT_WORK(&cmd->work, NULL);
1383 kref_init(&cmd->cmd_kref);
1384
1385 cmd->se_tfo = tfo;
1386 cmd->se_sess = se_sess;
1387 cmd->data_length = data_length;
1388 cmd->data_direction = data_direction;
1389 cmd->sam_task_attr = task_attr;
1390 cmd->sense_buffer = sense_buffer;
1391 cmd->orig_fe_lun = unpacked_lun;
1392
1393 cmd->state_active = false;
1394 }
1395 EXPORT_SYMBOL(transport_init_se_cmd);
1396
1397 static sense_reason_t
1398 transport_check_alloc_task_attr(struct se_cmd *cmd)
1399 {
1400 struct se_device *dev = cmd->se_dev;
1401
1402 /*
1403 * Check if SAM Task Attribute emulation is enabled for this
1404 * struct se_device storage object
1405 */
1406 if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1407 return 0;
1408
1409 if (cmd->sam_task_attr == TCM_ACA_TAG) {
1410 pr_debug("SAM Task Attribute ACA"
1411 " emulation is not supported\n");
1412 return TCM_INVALID_CDB_FIELD;
1413 }
1414
1415 return 0;
1416 }
1417
1418 sense_reason_t
1419 target_cmd_init_cdb(struct se_cmd *cmd, unsigned char *cdb)
1420 {
1421 sense_reason_t ret;
1422
1423 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1424 /*
1425 * Ensure that the received CDB is less than the max (252 + 8) bytes
1426 * for VARIABLE_LENGTH_CMD
1427 */
1428 if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1429 pr_err("Received SCSI CDB with command_size: %d that"
1430 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1431 scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1432 ret = TCM_INVALID_CDB_FIELD;
1433 goto err;
1434 }
1435 /*
1436 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1437 * allocate the additional extended CDB buffer now.. Otherwise
1438 * setup the pointer from __t_task_cdb to t_task_cdb.
1439 */
1440 if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1441 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1442 GFP_KERNEL);
1443 if (!cmd->t_task_cdb) {
1444 pr_err("Unable to allocate cmd->t_task_cdb"
1445 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1446 scsi_command_size(cdb),
1447 (unsigned long)sizeof(cmd->__t_task_cdb));
1448 ret = TCM_OUT_OF_RESOURCES;
1449 goto err;
1450 }
1451 }
1452 /*
1453 * Copy the original CDB into cmd->
1454 */
1455 memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1456
1457 trace_target_sequencer_start(cmd);
1458 return 0;
1459
1460 err:
1461 /*
1462 * Copy the CDB here to allow trace_target_cmd_complete() to
1463 * print the cdb to the trace buffers.
1464 */
1465 memcpy(cmd->t_task_cdb, cdb, min(scsi_command_size(cdb),
1466 (unsigned int)TCM_MAX_COMMAND_SIZE));
1467 return ret;
1468 }
1469 EXPORT_SYMBOL(target_cmd_init_cdb);
1470
1471 sense_reason_t
1472 target_cmd_parse_cdb(struct se_cmd *cmd)
1473 {
1474 struct se_device *dev = cmd->se_dev;
1475 sense_reason_t ret;
1476
1477 ret = dev->transport->parse_cdb(cmd);
1478 if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1479 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1480 cmd->se_tfo->fabric_name,
1481 cmd->se_sess->se_node_acl->initiatorname,
1482 cmd->t_task_cdb[0]);
1483 if (ret)
1484 return ret;
1485
1486 ret = transport_check_alloc_task_attr(cmd);
1487 if (ret)
1488 return ret;
1489
1490 cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1491 atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1492 return 0;
1493 }
1494 EXPORT_SYMBOL(target_cmd_parse_cdb);
1495
1496 /*
1497 * Used by fabric module frontends to queue tasks directly.
1498 * May only be used from process context.
1499 */
1500 int transport_handle_cdb_direct(
1501 struct se_cmd *cmd)
1502 {
1503 sense_reason_t ret;
1504
1505 if (!cmd->se_lun) {
1506 dump_stack();
1507 pr_err("cmd->se_lun is NULL\n");
1508 return -EINVAL;
1509 }
1510 if (in_interrupt()) {
1511 dump_stack();
1512 pr_err("transport_generic_handle_cdb cannot be called"
1513 " from interrupt context\n");
1514 return -EINVAL;
1515 }
1516 /*
1517 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1518 * outstanding descriptors are handled correctly during shutdown via
1519 * transport_wait_for_tasks()
1520 *
1521 * Also, we don't take cmd->t_state_lock here as we only expect
1522 * this to be called for initial descriptor submission.
1523 */
1524 cmd->t_state = TRANSPORT_NEW_CMD;
1525 cmd->transport_state |= CMD_T_ACTIVE;
1526
1527 /*
1528 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1529 * so follow TRANSPORT_NEW_CMD processing thread context usage
1530 * and call transport_generic_request_failure() if necessary..
1531 */
1532 ret = transport_generic_new_cmd(cmd);
1533 if (ret)
1534 transport_generic_request_failure(cmd, ret);
1535 return 0;
1536 }
1537 EXPORT_SYMBOL(transport_handle_cdb_direct);
1538
1539 sense_reason_t
1540 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1541 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1542 {
1543 if (!sgl || !sgl_count)
1544 return 0;
1545
1546 /*
1547 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1548 * scatterlists already have been set to follow what the fabric
1549 * passes for the original expected data transfer length.
1550 */
1551 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1552 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1553 " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1554 return TCM_INVALID_CDB_FIELD;
1555 }
1556
1557 cmd->t_data_sg = sgl;
1558 cmd->t_data_nents = sgl_count;
1559 cmd->t_bidi_data_sg = sgl_bidi;
1560 cmd->t_bidi_data_nents = sgl_bidi_count;
1561
1562 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1563 return 0;
1564 }
1565
1566 /**
1567 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1568 * se_cmd + use pre-allocated SGL memory.
1569 *
1570 * @se_cmd: command descriptor to submit
1571 * @se_sess: associated se_sess for endpoint
1572 * @cdb: pointer to SCSI CDB
1573 * @sense: pointer to SCSI sense buffer
1574 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1575 * @data_length: fabric expected data transfer length
1576 * @task_attr: SAM task attribute
1577 * @data_dir: DMA data direction
1578 * @flags: flags for command submission from target_sc_flags_tables
1579 * @sgl: struct scatterlist memory for unidirectional mapping
1580 * @sgl_count: scatterlist count for unidirectional mapping
1581 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1582 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1583 * @sgl_prot: struct scatterlist memory protection information
1584 * @sgl_prot_count: scatterlist count for protection information
1585 *
1586 * Task tags are supported if the caller has set @se_cmd->tag.
1587 *
1588 * Returns non zero to signal active I/O shutdown failure. All other
1589 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1590 * but still return zero here.
1591 *
1592 * This may only be called from process context, and also currently
1593 * assumes internal allocation of fabric payload buffer by target-core.
1594 */
1595 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1596 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1597 u32 data_length, int task_attr, int data_dir, int flags,
1598 struct scatterlist *sgl, u32 sgl_count,
1599 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1600 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1601 {
1602 struct se_portal_group *se_tpg;
1603 sense_reason_t rc;
1604 int ret;
1605
1606 se_tpg = se_sess->se_tpg;
1607 BUG_ON(!se_tpg);
1608 BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1609 BUG_ON(in_interrupt());
1610 /*
1611 * Initialize se_cmd for target operation. From this point
1612 * exceptions are handled by sending exception status via
1613 * target_core_fabric_ops->queue_status() callback
1614 */
1615 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1616 data_length, data_dir, task_attr, sense,
1617 unpacked_lun);
1618
1619 if (flags & TARGET_SCF_USE_CPUID)
1620 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1621 else
1622 se_cmd->cpuid = WORK_CPU_UNBOUND;
1623
1624 if (flags & TARGET_SCF_UNKNOWN_SIZE)
1625 se_cmd->unknown_data_length = 1;
1626 /*
1627 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1628 * se_sess->sess_cmd_list. A second kref_get here is necessary
1629 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1630 * kref_put() to happen during fabric packet acknowledgement.
1631 */
1632 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1633 if (ret)
1634 return ret;
1635 /*
1636 * Signal bidirectional data payloads to target-core
1637 */
1638 if (flags & TARGET_SCF_BIDI_OP)
1639 se_cmd->se_cmd_flags |= SCF_BIDI;
1640
1641 rc = target_cmd_init_cdb(se_cmd, cdb);
1642 if (rc) {
1643 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1644 target_put_sess_cmd(se_cmd);
1645 return 0;
1646 }
1647
1648 /*
1649 * Locate se_lun pointer and attach it to struct se_cmd
1650 */
1651 rc = transport_lookup_cmd_lun(se_cmd);
1652 if (rc) {
1653 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1654 target_put_sess_cmd(se_cmd);
1655 return 0;
1656 }
1657
1658 rc = target_cmd_parse_cdb(se_cmd);
1659 if (rc != 0) {
1660 transport_generic_request_failure(se_cmd, rc);
1661 return 0;
1662 }
1663
1664 /*
1665 * Save pointers for SGLs containing protection information,
1666 * if present.
1667 */
1668 if (sgl_prot_count) {
1669 se_cmd->t_prot_sg = sgl_prot;
1670 se_cmd->t_prot_nents = sgl_prot_count;
1671 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1672 }
1673
1674 /*
1675 * When a non zero sgl_count has been passed perform SGL passthrough
1676 * mapping for pre-allocated fabric memory instead of having target
1677 * core perform an internal SGL allocation..
1678 */
1679 if (sgl_count != 0) {
1680 BUG_ON(!sgl);
1681
1682 /*
1683 * A work-around for tcm_loop as some userspace code via
1684 * scsi-generic do not memset their associated read buffers,
1685 * so go ahead and do that here for type non-data CDBs. Also
1686 * note that this is currently guaranteed to be a single SGL
1687 * for this case by target core in target_setup_cmd_from_cdb()
1688 * -> transport_generic_cmd_sequencer().
1689 */
1690 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1691 se_cmd->data_direction == DMA_FROM_DEVICE) {
1692 unsigned char *buf = NULL;
1693
1694 if (sgl)
1695 buf = kmap(sg_page(sgl)) + sgl->offset;
1696
1697 if (buf) {
1698 memset(buf, 0, sgl->length);
1699 kunmap(sg_page(sgl));
1700 }
1701 }
1702
1703 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1704 sgl_bidi, sgl_bidi_count);
1705 if (rc != 0) {
1706 transport_generic_request_failure(se_cmd, rc);
1707 return 0;
1708 }
1709 }
1710
1711 /*
1712 * Check if we need to delay processing because of ALUA
1713 * Active/NonOptimized primary access state..
1714 */
1715 core_alua_check_nonop_delay(se_cmd);
1716
1717 transport_handle_cdb_direct(se_cmd);
1718 return 0;
1719 }
1720 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1721
1722 /**
1723 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1724 *
1725 * @se_cmd: command descriptor to submit
1726 * @se_sess: associated se_sess for endpoint
1727 * @cdb: pointer to SCSI CDB
1728 * @sense: pointer to SCSI sense buffer
1729 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1730 * @data_length: fabric expected data transfer length
1731 * @task_attr: SAM task attribute
1732 * @data_dir: DMA data direction
1733 * @flags: flags for command submission from target_sc_flags_tables
1734 *
1735 * Task tags are supported if the caller has set @se_cmd->tag.
1736 *
1737 * Returns non zero to signal active I/O shutdown failure. All other
1738 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1739 * but still return zero here.
1740 *
1741 * This may only be called from process context, and also currently
1742 * assumes internal allocation of fabric payload buffer by target-core.
1743 *
1744 * It also assumes interal target core SGL memory allocation.
1745 */
1746 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1747 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1748 u32 data_length, int task_attr, int data_dir, int flags)
1749 {
1750 return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1751 unpacked_lun, data_length, task_attr, data_dir,
1752 flags, NULL, 0, NULL, 0, NULL, 0);
1753 }
1754 EXPORT_SYMBOL(target_submit_cmd);
1755
1756 static void target_complete_tmr_failure(struct work_struct *work)
1757 {
1758 struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1759
1760 se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1761 se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1762
1763 transport_lun_remove_cmd(se_cmd);
1764 transport_cmd_check_stop_to_fabric(se_cmd);
1765 }
1766
1767 static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
1768 u64 *unpacked_lun)
1769 {
1770 struct se_cmd *se_cmd;
1771 unsigned long flags;
1772 bool ret = false;
1773
1774 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
1775 list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
1776 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1777 continue;
1778
1779 if (se_cmd->tag == tag) {
1780 *unpacked_lun = se_cmd->orig_fe_lun;
1781 ret = true;
1782 break;
1783 }
1784 }
1785 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
1786
1787 return ret;
1788 }
1789
1790 /**
1791 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1792 * for TMR CDBs
1793 *
1794 * @se_cmd: command descriptor to submit
1795 * @se_sess: associated se_sess for endpoint
1796 * @sense: pointer to SCSI sense buffer
1797 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1798 * @fabric_tmr_ptr: fabric context for TMR req
1799 * @tm_type: Type of TM request
1800 * @gfp: gfp type for caller
1801 * @tag: referenced task tag for TMR_ABORT_TASK
1802 * @flags: submit cmd flags
1803 *
1804 * Callable from all contexts.
1805 **/
1806
1807 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1808 unsigned char *sense, u64 unpacked_lun,
1809 void *fabric_tmr_ptr, unsigned char tm_type,
1810 gfp_t gfp, u64 tag, int flags)
1811 {
1812 struct se_portal_group *se_tpg;
1813 int ret;
1814
1815 se_tpg = se_sess->se_tpg;
1816 BUG_ON(!se_tpg);
1817
1818 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1819 0, DMA_NONE, TCM_SIMPLE_TAG, sense, unpacked_lun);
1820 /*
1821 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1822 * allocation failure.
1823 */
1824 ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1825 if (ret < 0)
1826 return -ENOMEM;
1827
1828 if (tm_type == TMR_ABORT_TASK)
1829 se_cmd->se_tmr_req->ref_task_tag = tag;
1830
1831 /* See target_submit_cmd for commentary */
1832 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1833 if (ret) {
1834 core_tmr_release_req(se_cmd->se_tmr_req);
1835 return ret;
1836 }
1837 /*
1838 * If this is ABORT_TASK with no explicit fabric provided LUN,
1839 * go ahead and search active session tags for a match to figure
1840 * out unpacked_lun for the original se_cmd.
1841 */
1842 if (tm_type == TMR_ABORT_TASK && (flags & TARGET_SCF_LOOKUP_LUN_FROM_TAG)) {
1843 if (!target_lookup_lun_from_tag(se_sess, tag, &unpacked_lun))
1844 goto failure;
1845 }
1846
1847 ret = transport_lookup_tmr_lun(se_cmd);
1848 if (ret)
1849 goto failure;
1850
1851 transport_generic_handle_tmr(se_cmd);
1852 return 0;
1853
1854 /*
1855 * For callback during failure handling, push this work off
1856 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1857 */
1858 failure:
1859 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1860 schedule_work(&se_cmd->work);
1861 return 0;
1862 }
1863 EXPORT_SYMBOL(target_submit_tmr);
1864
1865 /*
1866 * Handle SAM-esque emulation for generic transport request failures.
1867 */
1868 void transport_generic_request_failure(struct se_cmd *cmd,
1869 sense_reason_t sense_reason)
1870 {
1871 int ret = 0, post_ret;
1872
1873 pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
1874 sense_reason);
1875 target_show_cmd("-----[ ", cmd);
1876
1877 /*
1878 * For SAM Task Attribute emulation for failed struct se_cmd
1879 */
1880 transport_complete_task_attr(cmd);
1881
1882 if (cmd->transport_complete_callback)
1883 cmd->transport_complete_callback(cmd, false, &post_ret);
1884
1885 if (cmd->transport_state & CMD_T_ABORTED) {
1886 INIT_WORK(&cmd->work, target_abort_work);
1887 queue_work(target_completion_wq, &cmd->work);
1888 return;
1889 }
1890
1891 switch (sense_reason) {
1892 case TCM_NON_EXISTENT_LUN:
1893 case TCM_UNSUPPORTED_SCSI_OPCODE:
1894 case TCM_INVALID_CDB_FIELD:
1895 case TCM_INVALID_PARAMETER_LIST:
1896 case TCM_PARAMETER_LIST_LENGTH_ERROR:
1897 case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1898 case TCM_UNKNOWN_MODE_PAGE:
1899 case TCM_WRITE_PROTECTED:
1900 case TCM_ADDRESS_OUT_OF_RANGE:
1901 case TCM_CHECK_CONDITION_ABORT_CMD:
1902 case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1903 case TCM_CHECK_CONDITION_NOT_READY:
1904 case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1905 case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1906 case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1907 case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1908 case TCM_TOO_MANY_TARGET_DESCS:
1909 case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
1910 case TCM_TOO_MANY_SEGMENT_DESCS:
1911 case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
1912 break;
1913 case TCM_OUT_OF_RESOURCES:
1914 cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
1915 goto queue_status;
1916 case TCM_LUN_BUSY:
1917 cmd->scsi_status = SAM_STAT_BUSY;
1918 goto queue_status;
1919 case TCM_RESERVATION_CONFLICT:
1920 /*
1921 * No SENSE Data payload for this case, set SCSI Status
1922 * and queue the response to $FABRIC_MOD.
1923 *
1924 * Uses linux/include/scsi/scsi.h SAM status codes defs
1925 */
1926 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1927 /*
1928 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1929 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1930 * CONFLICT STATUS.
1931 *
1932 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1933 */
1934 if (cmd->se_sess &&
1935 cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl
1936 == TARGET_UA_INTLCK_CTRL_ESTABLISH_UA) {
1937 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1938 cmd->orig_fe_lun, 0x2C,
1939 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1940 }
1941
1942 goto queue_status;
1943 default:
1944 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1945 cmd->t_task_cdb[0], sense_reason);
1946 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1947 break;
1948 }
1949
1950 ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1951 if (ret)
1952 goto queue_full;
1953
1954 check_stop:
1955 transport_lun_remove_cmd(cmd);
1956 transport_cmd_check_stop_to_fabric(cmd);
1957 return;
1958
1959 queue_status:
1960 trace_target_cmd_complete(cmd);
1961 ret = cmd->se_tfo->queue_status(cmd);
1962 if (!ret)
1963 goto check_stop;
1964 queue_full:
1965 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
1966 }
1967 EXPORT_SYMBOL(transport_generic_request_failure);
1968
1969 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1970 {
1971 sense_reason_t ret;
1972
1973 if (!cmd->execute_cmd) {
1974 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1975 goto err;
1976 }
1977 if (do_checks) {
1978 /*
1979 * Check for an existing UNIT ATTENTION condition after
1980 * target_handle_task_attr() has done SAM task attr
1981 * checking, and possibly have already defered execution
1982 * out to target_restart_delayed_cmds() context.
1983 */
1984 ret = target_scsi3_ua_check(cmd);
1985 if (ret)
1986 goto err;
1987
1988 ret = target_alua_state_check(cmd);
1989 if (ret)
1990 goto err;
1991
1992 ret = target_check_reservation(cmd);
1993 if (ret) {
1994 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1995 goto err;
1996 }
1997 }
1998
1999 ret = cmd->execute_cmd(cmd);
2000 if (!ret)
2001 return;
2002 err:
2003 spin_lock_irq(&cmd->t_state_lock);
2004 cmd->transport_state &= ~CMD_T_SENT;
2005 spin_unlock_irq(&cmd->t_state_lock);
2006
2007 transport_generic_request_failure(cmd, ret);
2008 }
2009
2010 static int target_write_prot_action(struct se_cmd *cmd)
2011 {
2012 u32 sectors;
2013 /*
2014 * Perform WRITE_INSERT of PI using software emulation when backend
2015 * device has PI enabled, if the transport has not already generated
2016 * PI using hardware WRITE_INSERT offload.
2017 */
2018 switch (cmd->prot_op) {
2019 case TARGET_PROT_DOUT_INSERT:
2020 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
2021 sbc_dif_generate(cmd);
2022 break;
2023 case TARGET_PROT_DOUT_STRIP:
2024 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
2025 break;
2026
2027 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
2028 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2029 sectors, 0, cmd->t_prot_sg, 0);
2030 if (unlikely(cmd->pi_err)) {
2031 spin_lock_irq(&cmd->t_state_lock);
2032 cmd->transport_state &= ~CMD_T_SENT;
2033 spin_unlock_irq(&cmd->t_state_lock);
2034 transport_generic_request_failure(cmd, cmd->pi_err);
2035 return -1;
2036 }
2037 break;
2038 default:
2039 break;
2040 }
2041
2042 return 0;
2043 }
2044
2045 static bool target_handle_task_attr(struct se_cmd *cmd)
2046 {
2047 struct se_device *dev = cmd->se_dev;
2048
2049 if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2050 return false;
2051
2052 cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
2053
2054 /*
2055 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
2056 * to allow the passed struct se_cmd list of tasks to the front of the list.
2057 */
2058 switch (cmd->sam_task_attr) {
2059 case TCM_HEAD_TAG:
2060 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
2061 cmd->t_task_cdb[0]);
2062 return false;
2063 case TCM_ORDERED_TAG:
2064 atomic_inc_mb(&dev->dev_ordered_sync);
2065
2066 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
2067 cmd->t_task_cdb[0]);
2068
2069 /*
2070 * Execute an ORDERED command if no other older commands
2071 * exist that need to be completed first.
2072 */
2073 if (!atomic_read(&dev->simple_cmds))
2074 return false;
2075 break;
2076 default:
2077 /*
2078 * For SIMPLE and UNTAGGED Task Attribute commands
2079 */
2080 atomic_inc_mb(&dev->simple_cmds);
2081 break;
2082 }
2083
2084 if (atomic_read(&dev->dev_ordered_sync) == 0)
2085 return false;
2086
2087 spin_lock(&dev->delayed_cmd_lock);
2088 list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
2089 spin_unlock(&dev->delayed_cmd_lock);
2090
2091 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
2092 cmd->t_task_cdb[0], cmd->sam_task_attr);
2093 return true;
2094 }
2095
2096 void target_execute_cmd(struct se_cmd *cmd)
2097 {
2098 /*
2099 * Determine if frontend context caller is requesting the stopping of
2100 * this command for frontend exceptions.
2101 *
2102 * If the received CDB has already been aborted stop processing it here.
2103 */
2104 if (target_cmd_interrupted(cmd))
2105 return;
2106
2107 spin_lock_irq(&cmd->t_state_lock);
2108 cmd->t_state = TRANSPORT_PROCESSING;
2109 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
2110 spin_unlock_irq(&cmd->t_state_lock);
2111
2112 if (target_write_prot_action(cmd))
2113 return;
2114
2115 if (target_handle_task_attr(cmd)) {
2116 spin_lock_irq(&cmd->t_state_lock);
2117 cmd->transport_state &= ~CMD_T_SENT;
2118 spin_unlock_irq(&cmd->t_state_lock);
2119 return;
2120 }
2121
2122 __target_execute_cmd(cmd, true);
2123 }
2124 EXPORT_SYMBOL(target_execute_cmd);
2125
2126 /*
2127 * Process all commands up to the last received ORDERED task attribute which
2128 * requires another blocking boundary
2129 */
2130 static void target_restart_delayed_cmds(struct se_device *dev)
2131 {
2132 for (;;) {
2133 struct se_cmd *cmd;
2134
2135 spin_lock(&dev->delayed_cmd_lock);
2136 if (list_empty(&dev->delayed_cmd_list)) {
2137 spin_unlock(&dev->delayed_cmd_lock);
2138 break;
2139 }
2140
2141 cmd = list_entry(dev->delayed_cmd_list.next,
2142 struct se_cmd, se_delayed_node);
2143 list_del(&cmd->se_delayed_node);
2144 spin_unlock(&dev->delayed_cmd_lock);
2145
2146 cmd->transport_state |= CMD_T_SENT;
2147
2148 __target_execute_cmd(cmd, true);
2149
2150 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
2151 break;
2152 }
2153 }
2154
2155 /*
2156 * Called from I/O completion to determine which dormant/delayed
2157 * and ordered cmds need to have their tasks added to the execution queue.
2158 */
2159 static void transport_complete_task_attr(struct se_cmd *cmd)
2160 {
2161 struct se_device *dev = cmd->se_dev;
2162
2163 if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2164 return;
2165
2166 if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2167 goto restart;
2168
2169 if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
2170 atomic_dec_mb(&dev->simple_cmds);
2171 dev->dev_cur_ordered_id++;
2172 } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
2173 dev->dev_cur_ordered_id++;
2174 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
2175 dev->dev_cur_ordered_id);
2176 } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2177 atomic_dec_mb(&dev->dev_ordered_sync);
2178
2179 dev->dev_cur_ordered_id++;
2180 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
2181 dev->dev_cur_ordered_id);
2182 }
2183 cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2184
2185 restart:
2186 target_restart_delayed_cmds(dev);
2187 }
2188
2189 static void transport_complete_qf(struct se_cmd *cmd)
2190 {
2191 int ret = 0;
2192
2193 transport_complete_task_attr(cmd);
2194 /*
2195 * If a fabric driver ->write_pending() or ->queue_data_in() callback
2196 * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2197 * the same callbacks should not be retried. Return CHECK_CONDITION
2198 * if a scsi_status is not already set.
2199 *
2200 * If a fabric driver ->queue_status() has returned non zero, always
2201 * keep retrying no matter what..
2202 */
2203 if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2204 if (cmd->scsi_status)
2205 goto queue_status;
2206
2207 translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2208 goto queue_status;
2209 }
2210
2211 /*
2212 * Check if we need to send a sense buffer from
2213 * the struct se_cmd in question. We do NOT want
2214 * to take this path of the IO has been marked as
2215 * needing to be treated like a "normal read". This
2216 * is the case if it's a tape read, and either the
2217 * FM, EOM, or ILI bits are set, but there is no
2218 * sense data.
2219 */
2220 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2221 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2222 goto queue_status;
2223
2224 switch (cmd->data_direction) {
2225 case DMA_FROM_DEVICE:
2226 /* queue status if not treating this as a normal read */
2227 if (cmd->scsi_status &&
2228 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2229 goto queue_status;
2230
2231 trace_target_cmd_complete(cmd);
2232 ret = cmd->se_tfo->queue_data_in(cmd);
2233 break;
2234 case DMA_TO_DEVICE:
2235 if (cmd->se_cmd_flags & SCF_BIDI) {
2236 ret = cmd->se_tfo->queue_data_in(cmd);
2237 break;
2238 }
2239 /* fall through */
2240 case DMA_NONE:
2241 queue_status:
2242 trace_target_cmd_complete(cmd);
2243 ret = cmd->se_tfo->queue_status(cmd);
2244 break;
2245 default:
2246 break;
2247 }
2248
2249 if (ret < 0) {
2250 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2251 return;
2252 }
2253 transport_lun_remove_cmd(cmd);
2254 transport_cmd_check_stop_to_fabric(cmd);
2255 }
2256
2257 static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2258 int err, bool write_pending)
2259 {
2260 /*
2261 * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2262 * ->queue_data_in() callbacks from new process context.
2263 *
2264 * Otherwise for other errors, transport_complete_qf() will send
2265 * CHECK_CONDITION via ->queue_status() instead of attempting to
2266 * retry associated fabric driver data-transfer callbacks.
2267 */
2268 if (err == -EAGAIN || err == -ENOMEM) {
2269 cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2270 TRANSPORT_COMPLETE_QF_OK;
2271 } else {
2272 pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2273 cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2274 }
2275
2276 spin_lock_irq(&dev->qf_cmd_lock);
2277 list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2278 atomic_inc_mb(&dev->dev_qf_count);
2279 spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2280
2281 schedule_work(&cmd->se_dev->qf_work_queue);
2282 }
2283
2284 static bool target_read_prot_action(struct se_cmd *cmd)
2285 {
2286 switch (cmd->prot_op) {
2287 case TARGET_PROT_DIN_STRIP:
2288 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2289 u32 sectors = cmd->data_length >>
2290 ilog2(cmd->se_dev->dev_attrib.block_size);
2291
2292 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2293 sectors, 0, cmd->t_prot_sg,
2294 0);
2295 if (cmd->pi_err)
2296 return true;
2297 }
2298 break;
2299 case TARGET_PROT_DIN_INSERT:
2300 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2301 break;
2302
2303 sbc_dif_generate(cmd);
2304 break;
2305 default:
2306 break;
2307 }
2308
2309 return false;
2310 }
2311
2312 static void target_complete_ok_work(struct work_struct *work)
2313 {
2314 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2315 int ret;
2316
2317 /*
2318 * Check if we need to move delayed/dormant tasks from cmds on the
2319 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2320 * Attribute.
2321 */
2322 transport_complete_task_attr(cmd);
2323
2324 /*
2325 * Check to schedule QUEUE_FULL work, or execute an existing
2326 * cmd->transport_qf_callback()
2327 */
2328 if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2329 schedule_work(&cmd->se_dev->qf_work_queue);
2330
2331 /*
2332 * Check if we need to send a sense buffer from
2333 * the struct se_cmd in question. We do NOT want
2334 * to take this path of the IO has been marked as
2335 * needing to be treated like a "normal read". This
2336 * is the case if it's a tape read, and either the
2337 * FM, EOM, or ILI bits are set, but there is no
2338 * sense data.
2339 */
2340 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2341 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2342 WARN_ON(!cmd->scsi_status);
2343 ret = transport_send_check_condition_and_sense(
2344 cmd, 0, 1);
2345 if (ret)
2346 goto queue_full;
2347
2348 transport_lun_remove_cmd(cmd);
2349 transport_cmd_check_stop_to_fabric(cmd);
2350 return;
2351 }
2352 /*
2353 * Check for a callback, used by amongst other things
2354 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2355 */
2356 if (cmd->transport_complete_callback) {
2357 sense_reason_t rc;
2358 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2359 bool zero_dl = !(cmd->data_length);
2360 int post_ret = 0;
2361
2362 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2363 if (!rc && !post_ret) {
2364 if (caw && zero_dl)
2365 goto queue_rsp;
2366
2367 return;
2368 } else if (rc) {
2369 ret = transport_send_check_condition_and_sense(cmd,
2370 rc, 0);
2371 if (ret)
2372 goto queue_full;
2373
2374 transport_lun_remove_cmd(cmd);
2375 transport_cmd_check_stop_to_fabric(cmd);
2376 return;
2377 }
2378 }
2379
2380 queue_rsp:
2381 switch (cmd->data_direction) {
2382 case DMA_FROM_DEVICE:
2383 /*
2384 * if this is a READ-type IO, but SCSI status
2385 * is set, then skip returning data and just
2386 * return the status -- unless this IO is marked
2387 * as needing to be treated as a normal read,
2388 * in which case we want to go ahead and return
2389 * the data. This happens, for example, for tape
2390 * reads with the FM, EOM, or ILI bits set, with
2391 * no sense data.
2392 */
2393 if (cmd->scsi_status &&
2394 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2395 goto queue_status;
2396
2397 atomic_long_add(cmd->data_length,
2398 &cmd->se_lun->lun_stats.tx_data_octets);
2399 /*
2400 * Perform READ_STRIP of PI using software emulation when
2401 * backend had PI enabled, if the transport will not be
2402 * performing hardware READ_STRIP offload.
2403 */
2404 if (target_read_prot_action(cmd)) {
2405 ret = transport_send_check_condition_and_sense(cmd,
2406 cmd->pi_err, 0);
2407 if (ret)
2408 goto queue_full;
2409
2410 transport_lun_remove_cmd(cmd);
2411 transport_cmd_check_stop_to_fabric(cmd);
2412 return;
2413 }
2414
2415 trace_target_cmd_complete(cmd);
2416 ret = cmd->se_tfo->queue_data_in(cmd);
2417 if (ret)
2418 goto queue_full;
2419 break;
2420 case DMA_TO_DEVICE:
2421 atomic_long_add(cmd->data_length,
2422 &cmd->se_lun->lun_stats.rx_data_octets);
2423 /*
2424 * Check if we need to send READ payload for BIDI-COMMAND
2425 */
2426 if (cmd->se_cmd_flags & SCF_BIDI) {
2427 atomic_long_add(cmd->data_length,
2428 &cmd->se_lun->lun_stats.tx_data_octets);
2429 ret = cmd->se_tfo->queue_data_in(cmd);
2430 if (ret)
2431 goto queue_full;
2432 break;
2433 }
2434 /* fall through */
2435 case DMA_NONE:
2436 queue_status:
2437 trace_target_cmd_complete(cmd);
2438 ret = cmd->se_tfo->queue_status(cmd);
2439 if (ret)
2440 goto queue_full;
2441 break;
2442 default:
2443 break;
2444 }
2445
2446 transport_lun_remove_cmd(cmd);
2447 transport_cmd_check_stop_to_fabric(cmd);
2448 return;
2449
2450 queue_full:
2451 pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2452 " data_direction: %d\n", cmd, cmd->data_direction);
2453
2454 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2455 }
2456
2457 void target_free_sgl(struct scatterlist *sgl, int nents)
2458 {
2459 sgl_free_n_order(sgl, nents, 0);
2460 }
2461 EXPORT_SYMBOL(target_free_sgl);
2462
2463 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2464 {
2465 /*
2466 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2467 * emulation, and free + reset pointers if necessary..
2468 */
2469 if (!cmd->t_data_sg_orig)
2470 return;
2471
2472 kfree(cmd->t_data_sg);
2473 cmd->t_data_sg = cmd->t_data_sg_orig;
2474 cmd->t_data_sg_orig = NULL;
2475 cmd->t_data_nents = cmd->t_data_nents_orig;
2476 cmd->t_data_nents_orig = 0;
2477 }
2478
2479 static inline void transport_free_pages(struct se_cmd *cmd)
2480 {
2481 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2482 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2483 cmd->t_prot_sg = NULL;
2484 cmd->t_prot_nents = 0;
2485 }
2486
2487 if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2488 /*
2489 * Release special case READ buffer payload required for
2490 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2491 */
2492 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2493 target_free_sgl(cmd->t_bidi_data_sg,
2494 cmd->t_bidi_data_nents);
2495 cmd->t_bidi_data_sg = NULL;
2496 cmd->t_bidi_data_nents = 0;
2497 }
2498 transport_reset_sgl_orig(cmd);
2499 return;
2500 }
2501 transport_reset_sgl_orig(cmd);
2502
2503 target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2504 cmd->t_data_sg = NULL;
2505 cmd->t_data_nents = 0;
2506
2507 target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2508 cmd->t_bidi_data_sg = NULL;
2509 cmd->t_bidi_data_nents = 0;
2510 }
2511
2512 void *transport_kmap_data_sg(struct se_cmd *cmd)
2513 {
2514 struct scatterlist *sg = cmd->t_data_sg;
2515 struct page **pages;
2516 int i;
2517
2518 /*
2519 * We need to take into account a possible offset here for fabrics like
2520 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2521 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2522 */
2523 if (!cmd->t_data_nents)
2524 return NULL;
2525
2526 BUG_ON(!sg);
2527 if (cmd->t_data_nents == 1)
2528 return kmap(sg_page(sg)) + sg->offset;
2529
2530 /* >1 page. use vmap */
2531 pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2532 if (!pages)
2533 return NULL;
2534
2535 /* convert sg[] to pages[] */
2536 for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2537 pages[i] = sg_page(sg);
2538 }
2539
2540 cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
2541 kfree(pages);
2542 if (!cmd->t_data_vmap)
2543 return NULL;
2544
2545 return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2546 }
2547 EXPORT_SYMBOL(transport_kmap_data_sg);
2548
2549 void transport_kunmap_data_sg(struct se_cmd *cmd)
2550 {
2551 if (!cmd->t_data_nents) {
2552 return;
2553 } else if (cmd->t_data_nents == 1) {
2554 kunmap(sg_page(cmd->t_data_sg));
2555 return;
2556 }
2557
2558 vunmap(cmd->t_data_vmap);
2559 cmd->t_data_vmap = NULL;
2560 }
2561 EXPORT_SYMBOL(transport_kunmap_data_sg);
2562
2563 int
2564 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2565 bool zero_page, bool chainable)
2566 {
2567 gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2568
2569 *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2570 return *sgl ? 0 : -ENOMEM;
2571 }
2572 EXPORT_SYMBOL(target_alloc_sgl);
2573
2574 /*
2575 * Allocate any required resources to execute the command. For writes we
2576 * might not have the payload yet, so notify the fabric via a call to
2577 * ->write_pending instead. Otherwise place it on the execution queue.
2578 */
2579 sense_reason_t
2580 transport_generic_new_cmd(struct se_cmd *cmd)
2581 {
2582 unsigned long flags;
2583 int ret = 0;
2584 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2585
2586 if (cmd->prot_op != TARGET_PROT_NORMAL &&
2587 !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2588 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2589 cmd->prot_length, true, false);
2590 if (ret < 0)
2591 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2592 }
2593
2594 /*
2595 * Determine if the TCM fabric module has already allocated physical
2596 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2597 * beforehand.
2598 */
2599 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2600 cmd->data_length) {
2601
2602 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2603 (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2604 u32 bidi_length;
2605
2606 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2607 bidi_length = cmd->t_task_nolb *
2608 cmd->se_dev->dev_attrib.block_size;
2609 else
2610 bidi_length = cmd->data_length;
2611
2612 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2613 &cmd->t_bidi_data_nents,
2614 bidi_length, zero_flag, false);
2615 if (ret < 0)
2616 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2617 }
2618
2619 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2620 cmd->data_length, zero_flag, false);
2621 if (ret < 0)
2622 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2623 } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2624 cmd->data_length) {
2625 /*
2626 * Special case for COMPARE_AND_WRITE with fabrics
2627 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2628 */
2629 u32 caw_length = cmd->t_task_nolb *
2630 cmd->se_dev->dev_attrib.block_size;
2631
2632 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2633 &cmd->t_bidi_data_nents,
2634 caw_length, zero_flag, false);
2635 if (ret < 0)
2636 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2637 }
2638 /*
2639 * If this command is not a write we can execute it right here,
2640 * for write buffers we need to notify the fabric driver first
2641 * and let it call back once the write buffers are ready.
2642 */
2643 target_add_to_state_list(cmd);
2644 if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2645 target_execute_cmd(cmd);
2646 return 0;
2647 }
2648
2649 spin_lock_irqsave(&cmd->t_state_lock, flags);
2650 cmd->t_state = TRANSPORT_WRITE_PENDING;
2651 /*
2652 * Determine if frontend context caller is requesting the stopping of
2653 * this command for frontend exceptions.
2654 */
2655 if (cmd->transport_state & CMD_T_STOP &&
2656 !cmd->se_tfo->write_pending_must_be_called) {
2657 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2658 __func__, __LINE__, cmd->tag);
2659
2660 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2661
2662 complete_all(&cmd->t_transport_stop_comp);
2663 return 0;
2664 }
2665 cmd->transport_state &= ~CMD_T_ACTIVE;
2666 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2667
2668 ret = cmd->se_tfo->write_pending(cmd);
2669 if (ret)
2670 goto queue_full;
2671
2672 return 0;
2673
2674 queue_full:
2675 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2676 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2677 return 0;
2678 }
2679 EXPORT_SYMBOL(transport_generic_new_cmd);
2680
2681 static void transport_write_pending_qf(struct se_cmd *cmd)
2682 {
2683 unsigned long flags;
2684 int ret;
2685 bool stop;
2686
2687 spin_lock_irqsave(&cmd->t_state_lock, flags);
2688 stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2689 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2690
2691 if (stop) {
2692 pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2693 __func__, __LINE__, cmd->tag);
2694 complete_all(&cmd->t_transport_stop_comp);
2695 return;
2696 }
2697
2698 ret = cmd->se_tfo->write_pending(cmd);
2699 if (ret) {
2700 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2701 cmd);
2702 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2703 }
2704 }
2705
2706 static bool
2707 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2708 unsigned long *flags);
2709
2710 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2711 {
2712 unsigned long flags;
2713
2714 spin_lock_irqsave(&cmd->t_state_lock, flags);
2715 __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2716 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2717 }
2718
2719 /*
2720 * Call target_put_sess_cmd() and wait until target_release_cmd_kref(@cmd) has
2721 * finished.
2722 */
2723 void target_put_cmd_and_wait(struct se_cmd *cmd)
2724 {
2725 DECLARE_COMPLETION_ONSTACK(compl);
2726
2727 WARN_ON_ONCE(cmd->abrt_compl);
2728 cmd->abrt_compl = &compl;
2729 target_put_sess_cmd(cmd);
2730 wait_for_completion(&compl);
2731 }
2732
2733 /*
2734 * This function is called by frontend drivers after processing of a command
2735 * has finished.
2736 *
2737 * The protocol for ensuring that either the regular frontend command
2738 * processing flow or target_handle_abort() code drops one reference is as
2739 * follows:
2740 * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
2741 * the frontend driver to call this function synchronously or asynchronously.
2742 * That will cause one reference to be dropped.
2743 * - During regular command processing the target core sets CMD_T_COMPLETE
2744 * before invoking one of the .queue_*() functions.
2745 * - The code that aborts commands skips commands and TMFs for which
2746 * CMD_T_COMPLETE has been set.
2747 * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
2748 * commands that will be aborted.
2749 * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
2750 * transport_generic_free_cmd() skips its call to target_put_sess_cmd().
2751 * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
2752 * be called and will drop a reference.
2753 * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
2754 * will be called. target_handle_abort() will drop the final reference.
2755 */
2756 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2757 {
2758 DECLARE_COMPLETION_ONSTACK(compl);
2759 int ret = 0;
2760 bool aborted = false, tas = false;
2761
2762 if (wait_for_tasks)
2763 target_wait_free_cmd(cmd, &aborted, &tas);
2764
2765 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
2766 /*
2767 * Handle WRITE failure case where transport_generic_new_cmd()
2768 * has already added se_cmd to state_list, but fabric has
2769 * failed command before I/O submission.
2770 */
2771 if (cmd->state_active)
2772 target_remove_from_state_list(cmd);
2773
2774 if (cmd->se_lun)
2775 transport_lun_remove_cmd(cmd);
2776 }
2777 if (aborted)
2778 cmd->free_compl = &compl;
2779 ret = target_put_sess_cmd(cmd);
2780 if (aborted) {
2781 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2782 wait_for_completion(&compl);
2783 ret = 1;
2784 }
2785 return ret;
2786 }
2787 EXPORT_SYMBOL(transport_generic_free_cmd);
2788
2789 /**
2790 * target_get_sess_cmd - Add command to active ->sess_cmd_list
2791 * @se_cmd: command descriptor to add
2792 * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
2793 */
2794 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2795 {
2796 struct se_session *se_sess = se_cmd->se_sess;
2797 unsigned long flags;
2798 int ret = 0;
2799
2800 /*
2801 * Add a second kref if the fabric caller is expecting to handle
2802 * fabric acknowledgement that requires two target_put_sess_cmd()
2803 * invocations before se_cmd descriptor release.
2804 */
2805 if (ack_kref) {
2806 if (!kref_get_unless_zero(&se_cmd->cmd_kref))
2807 return -EINVAL;
2808
2809 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2810 }
2811
2812 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2813 if (se_sess->sess_tearing_down) {
2814 ret = -ESHUTDOWN;
2815 goto out;
2816 }
2817 list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2818 percpu_ref_get(&se_sess->cmd_count);
2819 out:
2820 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2821
2822 if (ret && ack_kref)
2823 target_put_sess_cmd(se_cmd);
2824
2825 return ret;
2826 }
2827 EXPORT_SYMBOL(target_get_sess_cmd);
2828
2829 static void target_free_cmd_mem(struct se_cmd *cmd)
2830 {
2831 transport_free_pages(cmd);
2832
2833 if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2834 core_tmr_release_req(cmd->se_tmr_req);
2835 if (cmd->t_task_cdb != cmd->__t_task_cdb)
2836 kfree(cmd->t_task_cdb);
2837 }
2838
2839 static void target_release_cmd_kref(struct kref *kref)
2840 {
2841 struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2842 struct se_session *se_sess = se_cmd->se_sess;
2843 struct completion *free_compl = se_cmd->free_compl;
2844 struct completion *abrt_compl = se_cmd->abrt_compl;
2845 unsigned long flags;
2846
2847 if (se_sess) {
2848 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2849 list_del_init(&se_cmd->se_cmd_list);
2850 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2851 }
2852
2853 target_free_cmd_mem(se_cmd);
2854 se_cmd->se_tfo->release_cmd(se_cmd);
2855 if (free_compl)
2856 complete(free_compl);
2857 if (abrt_compl)
2858 complete(abrt_compl);
2859
2860 percpu_ref_put(&se_sess->cmd_count);
2861 }
2862
2863 /**
2864 * target_put_sess_cmd - decrease the command reference count
2865 * @se_cmd: command to drop a reference from
2866 *
2867 * Returns 1 if and only if this target_put_sess_cmd() call caused the
2868 * refcount to drop to zero. Returns zero otherwise.
2869 */
2870 int target_put_sess_cmd(struct se_cmd *se_cmd)
2871 {
2872 return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2873 }
2874 EXPORT_SYMBOL(target_put_sess_cmd);
2875
2876 static const char *data_dir_name(enum dma_data_direction d)
2877 {
2878 switch (d) {
2879 case DMA_BIDIRECTIONAL: return "BIDI";
2880 case DMA_TO_DEVICE: return "WRITE";
2881 case DMA_FROM_DEVICE: return "READ";
2882 case DMA_NONE: return "NONE";
2883 }
2884
2885 return "(?)";
2886 }
2887
2888 static const char *cmd_state_name(enum transport_state_table t)
2889 {
2890 switch (t) {
2891 case TRANSPORT_NO_STATE: return "NO_STATE";
2892 case TRANSPORT_NEW_CMD: return "NEW_CMD";
2893 case TRANSPORT_WRITE_PENDING: return "WRITE_PENDING";
2894 case TRANSPORT_PROCESSING: return "PROCESSING";
2895 case TRANSPORT_COMPLETE: return "COMPLETE";
2896 case TRANSPORT_ISTATE_PROCESSING:
2897 return "ISTATE_PROCESSING";
2898 case TRANSPORT_COMPLETE_QF_WP: return "COMPLETE_QF_WP";
2899 case TRANSPORT_COMPLETE_QF_OK: return "COMPLETE_QF_OK";
2900 case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR";
2901 }
2902
2903 return "(?)";
2904 }
2905
2906 static void target_append_str(char **str, const char *txt)
2907 {
2908 char *prev = *str;
2909
2910 *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
2911 kstrdup(txt, GFP_ATOMIC);
2912 kfree(prev);
2913 }
2914
2915 /*
2916 * Convert a transport state bitmask into a string. The caller is
2917 * responsible for freeing the returned pointer.
2918 */
2919 static char *target_ts_to_str(u32 ts)
2920 {
2921 char *str = NULL;
2922
2923 if (ts & CMD_T_ABORTED)
2924 target_append_str(&str, "aborted");
2925 if (ts & CMD_T_ACTIVE)
2926 target_append_str(&str, "active");
2927 if (ts & CMD_T_COMPLETE)
2928 target_append_str(&str, "complete");
2929 if (ts & CMD_T_SENT)
2930 target_append_str(&str, "sent");
2931 if (ts & CMD_T_STOP)
2932 target_append_str(&str, "stop");
2933 if (ts & CMD_T_FABRIC_STOP)
2934 target_append_str(&str, "fabric_stop");
2935
2936 return str;
2937 }
2938
2939 static const char *target_tmf_name(enum tcm_tmreq_table tmf)
2940 {
2941 switch (tmf) {
2942 case TMR_ABORT_TASK: return "ABORT_TASK";
2943 case TMR_ABORT_TASK_SET: return "ABORT_TASK_SET";
2944 case TMR_CLEAR_ACA: return "CLEAR_ACA";
2945 case TMR_CLEAR_TASK_SET: return "CLEAR_TASK_SET";
2946 case TMR_LUN_RESET: return "LUN_RESET";
2947 case TMR_TARGET_WARM_RESET: return "TARGET_WARM_RESET";
2948 case TMR_TARGET_COLD_RESET: return "TARGET_COLD_RESET";
2949 case TMR_LUN_RESET_PRO: return "LUN_RESET_PRO";
2950 case TMR_UNKNOWN: break;
2951 }
2952 return "(?)";
2953 }
2954
2955 void target_show_cmd(const char *pfx, struct se_cmd *cmd)
2956 {
2957 char *ts_str = target_ts_to_str(cmd->transport_state);
2958 const u8 *cdb = cmd->t_task_cdb;
2959 struct se_tmr_req *tmf = cmd->se_tmr_req;
2960
2961 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2962 pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
2963 pfx, cdb[0], cdb[1], cmd->tag,
2964 data_dir_name(cmd->data_direction),
2965 cmd->se_tfo->get_cmd_state(cmd),
2966 cmd_state_name(cmd->t_state), cmd->data_length,
2967 kref_read(&cmd->cmd_kref), ts_str);
2968 } else {
2969 pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
2970 pfx, target_tmf_name(tmf->function), cmd->tag,
2971 tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
2972 cmd_state_name(cmd->t_state),
2973 kref_read(&cmd->cmd_kref), ts_str);
2974 }
2975 kfree(ts_str);
2976 }
2977 EXPORT_SYMBOL(target_show_cmd);
2978
2979 /**
2980 * target_sess_cmd_list_set_waiting - Set sess_tearing_down so no new commands are queued.
2981 * @se_sess: session to flag
2982 */
2983 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2984 {
2985 unsigned long flags;
2986
2987 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2988 se_sess->sess_tearing_down = 1;
2989 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2990
2991 percpu_ref_kill(&se_sess->cmd_count);
2992 }
2993 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2994
2995 /**
2996 * target_wait_for_sess_cmds - Wait for outstanding commands
2997 * @se_sess: session to wait for active I/O
2998 */
2999 void target_wait_for_sess_cmds(struct se_session *se_sess)
3000 {
3001 struct se_cmd *cmd;
3002 int ret;
3003
3004 WARN_ON_ONCE(!se_sess->sess_tearing_down);
3005
3006 do {
3007 ret = wait_event_timeout(se_sess->cmd_list_wq,
3008 percpu_ref_is_zero(&se_sess->cmd_count),
3009 180 * HZ);
3010 list_for_each_entry(cmd, &se_sess->sess_cmd_list, se_cmd_list)
3011 target_show_cmd("session shutdown: still waiting for ",
3012 cmd);
3013 } while (ret <= 0);
3014 }
3015 EXPORT_SYMBOL(target_wait_for_sess_cmds);
3016
3017 /*
3018 * Prevent that new percpu_ref_tryget_live() calls succeed and wait until
3019 * all references to the LUN have been released. Called during LUN shutdown.
3020 */
3021 void transport_clear_lun_ref(struct se_lun *lun)
3022 {
3023 percpu_ref_kill(&lun->lun_ref);
3024 wait_for_completion(&lun->lun_shutdown_comp);
3025 }
3026
3027 static bool
3028 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
3029 bool *aborted, bool *tas, unsigned long *flags)
3030 __releases(&cmd->t_state_lock)
3031 __acquires(&cmd->t_state_lock)
3032 {
3033
3034 assert_spin_locked(&cmd->t_state_lock);
3035 WARN_ON_ONCE(!irqs_disabled());
3036
3037 if (fabric_stop)
3038 cmd->transport_state |= CMD_T_FABRIC_STOP;
3039
3040 if (cmd->transport_state & CMD_T_ABORTED)
3041 *aborted = true;
3042
3043 if (cmd->transport_state & CMD_T_TAS)
3044 *tas = true;
3045
3046 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
3047 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3048 return false;
3049
3050 if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
3051 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3052 return false;
3053
3054 if (!(cmd->transport_state & CMD_T_ACTIVE))
3055 return false;
3056
3057 if (fabric_stop && *aborted)
3058 return false;
3059
3060 cmd->transport_state |= CMD_T_STOP;
3061
3062 target_show_cmd("wait_for_tasks: Stopping ", cmd);
3063
3064 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
3065
3066 while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
3067 180 * HZ))
3068 target_show_cmd("wait for tasks: ", cmd);
3069
3070 spin_lock_irqsave(&cmd->t_state_lock, *flags);
3071 cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
3072
3073 pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
3074 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
3075
3076 return true;
3077 }
3078
3079 /**
3080 * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
3081 * @cmd: command to wait on
3082 */
3083 bool transport_wait_for_tasks(struct se_cmd *cmd)
3084 {
3085 unsigned long flags;
3086 bool ret, aborted = false, tas = false;
3087
3088 spin_lock_irqsave(&cmd->t_state_lock, flags);
3089 ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
3090 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3091
3092 return ret;
3093 }
3094 EXPORT_SYMBOL(transport_wait_for_tasks);
3095
3096 struct sense_info {
3097 u8 key;
3098 u8 asc;
3099 u8 ascq;
3100 bool add_sector_info;
3101 };
3102
3103 static const struct sense_info sense_info_table[] = {
3104 [TCM_NO_SENSE] = {
3105 .key = NOT_READY
3106 },
3107 [TCM_NON_EXISTENT_LUN] = {
3108 .key = ILLEGAL_REQUEST,
3109 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
3110 },
3111 [TCM_UNSUPPORTED_SCSI_OPCODE] = {
3112 .key = ILLEGAL_REQUEST,
3113 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3114 },
3115 [TCM_SECTOR_COUNT_TOO_MANY] = {
3116 .key = ILLEGAL_REQUEST,
3117 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3118 },
3119 [TCM_UNKNOWN_MODE_PAGE] = {
3120 .key = ILLEGAL_REQUEST,
3121 .asc = 0x24, /* INVALID FIELD IN CDB */
3122 },
3123 [TCM_CHECK_CONDITION_ABORT_CMD] = {
3124 .key = ABORTED_COMMAND,
3125 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3126 .ascq = 0x03,
3127 },
3128 [TCM_INCORRECT_AMOUNT_OF_DATA] = {
3129 .key = ABORTED_COMMAND,
3130 .asc = 0x0c, /* WRITE ERROR */
3131 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3132 },
3133 [TCM_INVALID_CDB_FIELD] = {
3134 .key = ILLEGAL_REQUEST,
3135 .asc = 0x24, /* INVALID FIELD IN CDB */
3136 },
3137 [TCM_INVALID_PARAMETER_LIST] = {
3138 .key = ILLEGAL_REQUEST,
3139 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3140 },
3141 [TCM_TOO_MANY_TARGET_DESCS] = {
3142 .key = ILLEGAL_REQUEST,
3143 .asc = 0x26,
3144 .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3145 },
3146 [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3147 .key = ILLEGAL_REQUEST,
3148 .asc = 0x26,
3149 .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3150 },
3151 [TCM_TOO_MANY_SEGMENT_DESCS] = {
3152 .key = ILLEGAL_REQUEST,
3153 .asc = 0x26,
3154 .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3155 },
3156 [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3157 .key = ILLEGAL_REQUEST,
3158 .asc = 0x26,
3159 .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3160 },
3161 [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3162 .key = ILLEGAL_REQUEST,
3163 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3164 },
3165 [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3166 .key = ILLEGAL_REQUEST,
3167 .asc = 0x0c, /* WRITE ERROR */
3168 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3169 },
3170 [TCM_SERVICE_CRC_ERROR] = {
3171 .key = ABORTED_COMMAND,
3172 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3173 .ascq = 0x05, /* N/A */
3174 },
3175 [TCM_SNACK_REJECTED] = {
3176 .key = ABORTED_COMMAND,
3177 .asc = 0x11, /* READ ERROR */
3178 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3179 },
3180 [TCM_WRITE_PROTECTED] = {
3181 .key = DATA_PROTECT,
3182 .asc = 0x27, /* WRITE PROTECTED */
3183 },
3184 [TCM_ADDRESS_OUT_OF_RANGE] = {
3185 .key = ILLEGAL_REQUEST,
3186 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3187 },
3188 [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3189 .key = UNIT_ATTENTION,
3190 },
3191 [TCM_CHECK_CONDITION_NOT_READY] = {
3192 .key = NOT_READY,
3193 },
3194 [TCM_MISCOMPARE_VERIFY] = {
3195 .key = MISCOMPARE,
3196 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3197 .ascq = 0x00,
3198 },
3199 [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
3200 .key = ABORTED_COMMAND,
3201 .asc = 0x10,
3202 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
3203 .add_sector_info = true,
3204 },
3205 [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
3206 .key = ABORTED_COMMAND,
3207 .asc = 0x10,
3208 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
3209 .add_sector_info = true,
3210 },
3211 [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
3212 .key = ABORTED_COMMAND,
3213 .asc = 0x10,
3214 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
3215 .add_sector_info = true,
3216 },
3217 [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
3218 .key = COPY_ABORTED,
3219 .asc = 0x0d,
3220 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
3221
3222 },
3223 [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
3224 /*
3225 * Returning ILLEGAL REQUEST would cause immediate IO errors on
3226 * Solaris initiators. Returning NOT READY instead means the
3227 * operations will be retried a finite number of times and we
3228 * can survive intermittent errors.
3229 */
3230 .key = NOT_READY,
3231 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
3232 },
3233 [TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
3234 /*
3235 * From spc4r22 section5.7.7,5.7.8
3236 * If a PERSISTENT RESERVE OUT command with a REGISTER service action
3237 * or a REGISTER AND IGNORE EXISTING KEY service action or
3238 * REGISTER AND MOVE service actionis attempted,
3239 * but there are insufficient device server resources to complete the
3240 * operation, then the command shall be terminated with CHECK CONDITION
3241 * status, with the sense key set to ILLEGAL REQUEST,and the additonal
3242 * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
3243 */
3244 .key = ILLEGAL_REQUEST,
3245 .asc = 0x55,
3246 .ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
3247 },
3248 };
3249
3250 /**
3251 * translate_sense_reason - translate a sense reason into T10 key, asc and ascq
3252 * @cmd: SCSI command in which the resulting sense buffer or SCSI status will
3253 * be stored.
3254 * @reason: LIO sense reason code. If this argument has the value
3255 * TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If
3256 * dequeuing a unit attention fails due to multiple commands being processed
3257 * concurrently, set the command status to BUSY.
3258 *
3259 * Return: 0 upon success or -EINVAL if the sense buffer is too small.
3260 */
3261 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
3262 {
3263 const struct sense_info *si;
3264 u8 *buffer = cmd->sense_buffer;
3265 int r = (__force int)reason;
3266 u8 key, asc, ascq;
3267 bool desc_format = target_sense_desc_format(cmd->se_dev);
3268
3269 if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
3270 si = &sense_info_table[r];
3271 else
3272 si = &sense_info_table[(__force int)
3273 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3274
3275 key = si->key;
3276 if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
3277 if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc,
3278 &ascq)) {
3279 cmd->scsi_status = SAM_STAT_BUSY;
3280 return;
3281 }
3282 } else if (si->asc == 0) {
3283 WARN_ON_ONCE(cmd->scsi_asc == 0);
3284 asc = cmd->scsi_asc;
3285 ascq = cmd->scsi_ascq;
3286 } else {
3287 asc = si->asc;
3288 ascq = si->ascq;
3289 }
3290
3291 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
3292 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
3293 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
3294 scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
3295 if (si->add_sector_info)
3296 WARN_ON_ONCE(scsi_set_sense_information(buffer,
3297 cmd->scsi_sense_length,
3298 cmd->bad_sector) < 0);
3299 }
3300
3301 int
3302 transport_send_check_condition_and_sense(struct se_cmd *cmd,
3303 sense_reason_t reason, int from_transport)
3304 {
3305 unsigned long flags;
3306
3307 WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3308
3309 spin_lock_irqsave(&cmd->t_state_lock, flags);
3310 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
3311 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3312 return 0;
3313 }
3314 cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
3315 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3316
3317 if (!from_transport)
3318 translate_sense_reason(cmd, reason);
3319
3320 trace_target_cmd_complete(cmd);
3321 return cmd->se_tfo->queue_status(cmd);
3322 }
3323 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
3324
3325 /**
3326 * target_send_busy - Send SCSI BUSY status back to the initiator
3327 * @cmd: SCSI command for which to send a BUSY reply.
3328 *
3329 * Note: Only call this function if target_submit_cmd*() failed.
3330 */
3331 int target_send_busy(struct se_cmd *cmd)
3332 {
3333 WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3334
3335 cmd->scsi_status = SAM_STAT_BUSY;
3336 trace_target_cmd_complete(cmd);
3337 return cmd->se_tfo->queue_status(cmd);
3338 }
3339 EXPORT_SYMBOL(target_send_busy);
3340
3341 static void target_tmr_work(struct work_struct *work)
3342 {
3343 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3344 struct se_device *dev = cmd->se_dev;
3345 struct se_tmr_req *tmr = cmd->se_tmr_req;
3346 int ret;
3347
3348 if (cmd->transport_state & CMD_T_ABORTED)
3349 goto aborted;
3350
3351 switch (tmr->function) {
3352 case TMR_ABORT_TASK:
3353 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3354 break;
3355 case TMR_ABORT_TASK_SET:
3356 case TMR_CLEAR_ACA:
3357 case TMR_CLEAR_TASK_SET:
3358 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3359 break;
3360 case TMR_LUN_RESET:
3361 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3362 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3363 TMR_FUNCTION_REJECTED;
3364 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3365 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3366 cmd->orig_fe_lun, 0x29,
3367 ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3368 }
3369 break;
3370 case TMR_TARGET_WARM_RESET:
3371 tmr->response = TMR_FUNCTION_REJECTED;
3372 break;
3373 case TMR_TARGET_COLD_RESET:
3374 tmr->response = TMR_FUNCTION_REJECTED;
3375 break;
3376 default:
3377 pr_err("Unknown TMR function: 0x%02x.\n",
3378 tmr->function);
3379 tmr->response = TMR_FUNCTION_REJECTED;
3380 break;
3381 }
3382
3383 if (cmd->transport_state & CMD_T_ABORTED)
3384 goto aborted;
3385
3386 cmd->se_tfo->queue_tm_rsp(cmd);
3387
3388 transport_lun_remove_cmd(cmd);
3389 transport_cmd_check_stop_to_fabric(cmd);
3390 return;
3391
3392 aborted:
3393 target_handle_abort(cmd);
3394 }
3395
3396 int transport_generic_handle_tmr(
3397 struct se_cmd *cmd)
3398 {
3399 unsigned long flags;
3400 bool aborted = false;
3401
3402 spin_lock_irqsave(&cmd->t_state_lock, flags);
3403 if (cmd->transport_state & CMD_T_ABORTED) {
3404 aborted = true;
3405 } else {
3406 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3407 cmd->transport_state |= CMD_T_ACTIVE;
3408 }
3409 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3410
3411 if (aborted) {
3412 pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d ref_tag: %llu tag: %llu\n",
3413 cmd->se_tmr_req->function,
3414 cmd->se_tmr_req->ref_task_tag, cmd->tag);
3415 target_handle_abort(cmd);
3416 return 0;
3417 }
3418
3419 INIT_WORK(&cmd->work, target_tmr_work);
3420 schedule_work(&cmd->work);
3421 return 0;
3422 }
3423 EXPORT_SYMBOL(transport_generic_handle_tmr);
3424
3425 bool
3426 target_check_wce(struct se_device *dev)
3427 {
3428 bool wce = false;
3429
3430 if (dev->transport->get_write_cache)
3431 wce = dev->transport->get_write_cache(dev);
3432 else if (dev->dev_attrib.emulate_write_cache > 0)
3433 wce = true;
3434
3435 return wce;
3436 }
3437
3438 bool
3439 target_check_fua(struct se_device *dev)
3440 {
3441 return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3442 }
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