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Merge tag 'x86-fpu-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
[thirdparty/linux.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 /**
240 * transport_alloc_session - allocate a session object and initialize it
241 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
242 */
243 struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
244 {
245 struct se_session *se_sess;
246 int ret;
247
248 se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
249 if (!se_sess) {
250 pr_err("Unable to allocate struct se_session from"
251 " se_sess_cache\n");
252 return ERR_PTR(-ENOMEM);
253 }
254 ret = transport_init_session(se_sess);
255 if (ret < 0) {
256 kmem_cache_free(se_sess_cache, se_sess);
257 return ERR_PTR(ret);
258 }
259 se_sess->sup_prot_ops = sup_prot_ops;
260
261 return se_sess;
262 }
263 EXPORT_SYMBOL(transport_alloc_session);
264
265 /**
266 * transport_alloc_session_tags - allocate target driver private data
267 * @se_sess: Session pointer.
268 * @tag_num: Maximum number of in-flight commands between initiator and target.
269 * @tag_size: Size in bytes of the private data a target driver associates with
270 * each command.
271 */
272 int transport_alloc_session_tags(struct se_session *se_sess,
273 unsigned int tag_num, unsigned int tag_size)
274 {
275 int rc;
276
277 se_sess->sess_cmd_map = kvcalloc(tag_size, tag_num,
278 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
279 if (!se_sess->sess_cmd_map) {
280 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
281 return -ENOMEM;
282 }
283
284 rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
285 false, GFP_KERNEL, NUMA_NO_NODE);
286 if (rc < 0) {
287 pr_err("Unable to init se_sess->sess_tag_pool,"
288 " tag_num: %u\n", tag_num);
289 kvfree(se_sess->sess_cmd_map);
290 se_sess->sess_cmd_map = NULL;
291 return -ENOMEM;
292 }
293
294 return 0;
295 }
296 EXPORT_SYMBOL(transport_alloc_session_tags);
297
298 /**
299 * transport_init_session_tags - allocate a session and target driver private data
300 * @tag_num: Maximum number of in-flight commands between initiator and target.
301 * @tag_size: Size in bytes of the private data a target driver associates with
302 * each command.
303 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
304 */
305 static struct se_session *
306 transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
307 enum target_prot_op sup_prot_ops)
308 {
309 struct se_session *se_sess;
310 int rc;
311
312 if (tag_num != 0 && !tag_size) {
313 pr_err("init_session_tags called with percpu-ida tag_num:"
314 " %u, but zero tag_size\n", tag_num);
315 return ERR_PTR(-EINVAL);
316 }
317 if (!tag_num && tag_size) {
318 pr_err("init_session_tags called with percpu-ida tag_size:"
319 " %u, but zero tag_num\n", tag_size);
320 return ERR_PTR(-EINVAL);
321 }
322
323 se_sess = transport_alloc_session(sup_prot_ops);
324 if (IS_ERR(se_sess))
325 return se_sess;
326
327 rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
328 if (rc < 0) {
329 transport_free_session(se_sess);
330 return ERR_PTR(-ENOMEM);
331 }
332
333 return se_sess;
334 }
335
336 /*
337 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
338 */
339 void __transport_register_session(
340 struct se_portal_group *se_tpg,
341 struct se_node_acl *se_nacl,
342 struct se_session *se_sess,
343 void *fabric_sess_ptr)
344 {
345 const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
346 unsigned char buf[PR_REG_ISID_LEN];
347 unsigned long flags;
348
349 se_sess->se_tpg = se_tpg;
350 se_sess->fabric_sess_ptr = fabric_sess_ptr;
351 /*
352 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
353 *
354 * Only set for struct se_session's that will actually be moving I/O.
355 * eg: *NOT* discovery sessions.
356 */
357 if (se_nacl) {
358 /*
359 *
360 * Determine if fabric allows for T10-PI feature bits exposed to
361 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
362 *
363 * If so, then always save prot_type on a per se_node_acl node
364 * basis and re-instate the previous sess_prot_type to avoid
365 * disabling PI from below any previously initiator side
366 * registered LUNs.
367 */
368 if (se_nacl->saved_prot_type)
369 se_sess->sess_prot_type = se_nacl->saved_prot_type;
370 else if (tfo->tpg_check_prot_fabric_only)
371 se_sess->sess_prot_type = se_nacl->saved_prot_type =
372 tfo->tpg_check_prot_fabric_only(se_tpg);
373 /*
374 * If the fabric module supports an ISID based TransportID,
375 * save this value in binary from the fabric I_T Nexus now.
376 */
377 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
378 memset(&buf[0], 0, PR_REG_ISID_LEN);
379 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
380 &buf[0], PR_REG_ISID_LEN);
381 se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
382 }
383
384 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
385 /*
386 * The se_nacl->nacl_sess pointer will be set to the
387 * last active I_T Nexus for each struct se_node_acl.
388 */
389 se_nacl->nacl_sess = se_sess;
390
391 list_add_tail(&se_sess->sess_acl_list,
392 &se_nacl->acl_sess_list);
393 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
394 }
395 list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
396
397 pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
398 se_tpg->se_tpg_tfo->fabric_name, se_sess->fabric_sess_ptr);
399 }
400 EXPORT_SYMBOL(__transport_register_session);
401
402 void transport_register_session(
403 struct se_portal_group *se_tpg,
404 struct se_node_acl *se_nacl,
405 struct se_session *se_sess,
406 void *fabric_sess_ptr)
407 {
408 unsigned long flags;
409
410 spin_lock_irqsave(&se_tpg->session_lock, flags);
411 __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
412 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
413 }
414 EXPORT_SYMBOL(transport_register_session);
415
416 struct se_session *
417 target_setup_session(struct se_portal_group *tpg,
418 unsigned int tag_num, unsigned int tag_size,
419 enum target_prot_op prot_op,
420 const char *initiatorname, void *private,
421 int (*callback)(struct se_portal_group *,
422 struct se_session *, void *))
423 {
424 struct se_session *sess;
425
426 /*
427 * If the fabric driver is using percpu-ida based pre allocation
428 * of I/O descriptor tags, go ahead and perform that setup now..
429 */
430 if (tag_num != 0)
431 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
432 else
433 sess = transport_alloc_session(prot_op);
434
435 if (IS_ERR(sess))
436 return sess;
437
438 sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
439 (unsigned char *)initiatorname);
440 if (!sess->se_node_acl) {
441 transport_free_session(sess);
442 return ERR_PTR(-EACCES);
443 }
444 /*
445 * Go ahead and perform any remaining fabric setup that is
446 * required before transport_register_session().
447 */
448 if (callback != NULL) {
449 int rc = callback(tpg, sess, private);
450 if (rc) {
451 transport_free_session(sess);
452 return ERR_PTR(rc);
453 }
454 }
455
456 transport_register_session(tpg, sess->se_node_acl, sess, private);
457 return sess;
458 }
459 EXPORT_SYMBOL(target_setup_session);
460
461 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
462 {
463 struct se_session *se_sess;
464 ssize_t len = 0;
465
466 spin_lock_bh(&se_tpg->session_lock);
467 list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
468 if (!se_sess->se_node_acl)
469 continue;
470 if (!se_sess->se_node_acl->dynamic_node_acl)
471 continue;
472 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
473 break;
474
475 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
476 se_sess->se_node_acl->initiatorname);
477 len += 1; /* Include NULL terminator */
478 }
479 spin_unlock_bh(&se_tpg->session_lock);
480
481 return len;
482 }
483 EXPORT_SYMBOL(target_show_dynamic_sessions);
484
485 static void target_complete_nacl(struct kref *kref)
486 {
487 struct se_node_acl *nacl = container_of(kref,
488 struct se_node_acl, acl_kref);
489 struct se_portal_group *se_tpg = nacl->se_tpg;
490
491 if (!nacl->dynamic_stop) {
492 complete(&nacl->acl_free_comp);
493 return;
494 }
495
496 mutex_lock(&se_tpg->acl_node_mutex);
497 list_del_init(&nacl->acl_list);
498 mutex_unlock(&se_tpg->acl_node_mutex);
499
500 core_tpg_wait_for_nacl_pr_ref(nacl);
501 core_free_device_list_for_node(nacl, se_tpg);
502 kfree(nacl);
503 }
504
505 void target_put_nacl(struct se_node_acl *nacl)
506 {
507 kref_put(&nacl->acl_kref, target_complete_nacl);
508 }
509 EXPORT_SYMBOL(target_put_nacl);
510
511 void transport_deregister_session_configfs(struct se_session *se_sess)
512 {
513 struct se_node_acl *se_nacl;
514 unsigned long flags;
515 /*
516 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
517 */
518 se_nacl = se_sess->se_node_acl;
519 if (se_nacl) {
520 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
521 if (!list_empty(&se_sess->sess_acl_list))
522 list_del_init(&se_sess->sess_acl_list);
523 /*
524 * If the session list is empty, then clear the pointer.
525 * Otherwise, set the struct se_session pointer from the tail
526 * element of the per struct se_node_acl active session list.
527 */
528 if (list_empty(&se_nacl->acl_sess_list))
529 se_nacl->nacl_sess = NULL;
530 else {
531 se_nacl->nacl_sess = container_of(
532 se_nacl->acl_sess_list.prev,
533 struct se_session, sess_acl_list);
534 }
535 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
536 }
537 }
538 EXPORT_SYMBOL(transport_deregister_session_configfs);
539
540 void transport_free_session(struct se_session *se_sess)
541 {
542 struct se_node_acl *se_nacl = se_sess->se_node_acl;
543
544 /*
545 * Drop the se_node_acl->nacl_kref obtained from within
546 * core_tpg_get_initiator_node_acl().
547 */
548 if (se_nacl) {
549 struct se_portal_group *se_tpg = se_nacl->se_tpg;
550 const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
551 unsigned long flags;
552
553 se_sess->se_node_acl = NULL;
554
555 /*
556 * Also determine if we need to drop the extra ->cmd_kref if
557 * it had been previously dynamically generated, and
558 * the endpoint is not caching dynamic ACLs.
559 */
560 mutex_lock(&se_tpg->acl_node_mutex);
561 if (se_nacl->dynamic_node_acl &&
562 !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
563 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
564 if (list_empty(&se_nacl->acl_sess_list))
565 se_nacl->dynamic_stop = true;
566 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
567
568 if (se_nacl->dynamic_stop)
569 list_del_init(&se_nacl->acl_list);
570 }
571 mutex_unlock(&se_tpg->acl_node_mutex);
572
573 if (se_nacl->dynamic_stop)
574 target_put_nacl(se_nacl);
575
576 target_put_nacl(se_nacl);
577 }
578 if (se_sess->sess_cmd_map) {
579 sbitmap_queue_free(&se_sess->sess_tag_pool);
580 kvfree(se_sess->sess_cmd_map);
581 }
582 percpu_ref_exit(&se_sess->cmd_count);
583 kmem_cache_free(se_sess_cache, se_sess);
584 }
585 EXPORT_SYMBOL(transport_free_session);
586
587 static int target_release_res(struct se_device *dev, void *data)
588 {
589 struct se_session *sess = data;
590
591 if (dev->reservation_holder == sess)
592 target_release_reservation(dev);
593 return 0;
594 }
595
596 void transport_deregister_session(struct se_session *se_sess)
597 {
598 struct se_portal_group *se_tpg = se_sess->se_tpg;
599 unsigned long flags;
600
601 if (!se_tpg) {
602 transport_free_session(se_sess);
603 return;
604 }
605
606 spin_lock_irqsave(&se_tpg->session_lock, flags);
607 list_del(&se_sess->sess_list);
608 se_sess->se_tpg = NULL;
609 se_sess->fabric_sess_ptr = NULL;
610 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
611
612 /*
613 * Since the session is being removed, release SPC-2
614 * reservations held by the session that is disappearing.
615 */
616 target_for_each_device(target_release_res, se_sess);
617
618 pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
619 se_tpg->se_tpg_tfo->fabric_name);
620 /*
621 * If last kref is dropping now for an explicit NodeACL, awake sleeping
622 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
623 * removal context from within transport_free_session() code.
624 *
625 * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
626 * to release all remaining generate_node_acl=1 created ACL resources.
627 */
628
629 transport_free_session(se_sess);
630 }
631 EXPORT_SYMBOL(transport_deregister_session);
632
633 void target_remove_session(struct se_session *se_sess)
634 {
635 transport_deregister_session_configfs(se_sess);
636 transport_deregister_session(se_sess);
637 }
638 EXPORT_SYMBOL(target_remove_session);
639
640 static void target_remove_from_state_list(struct se_cmd *cmd)
641 {
642 struct se_device *dev = cmd->se_dev;
643 unsigned long flags;
644
645 if (!dev)
646 return;
647
648 spin_lock_irqsave(&dev->execute_task_lock, flags);
649 if (cmd->state_active) {
650 list_del(&cmd->state_list);
651 cmd->state_active = false;
652 }
653 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
654 }
655
656 /*
657 * This function is called by the target core after the target core has
658 * finished processing a SCSI command or SCSI TMF. Both the regular command
659 * processing code and the code for aborting commands can call this
660 * function. CMD_T_STOP is set if and only if another thread is waiting
661 * inside transport_wait_for_tasks() for t_transport_stop_comp.
662 */
663 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
664 {
665 unsigned long flags;
666
667 target_remove_from_state_list(cmd);
668
669 /*
670 * Clear struct se_cmd->se_lun before the handoff to FE.
671 */
672 cmd->se_lun = NULL;
673
674 spin_lock_irqsave(&cmd->t_state_lock, flags);
675 /*
676 * Determine if frontend context caller is requesting the stopping of
677 * this command for frontend exceptions.
678 */
679 if (cmd->transport_state & CMD_T_STOP) {
680 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
681 __func__, __LINE__, cmd->tag);
682
683 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
684
685 complete_all(&cmd->t_transport_stop_comp);
686 return 1;
687 }
688 cmd->transport_state &= ~CMD_T_ACTIVE;
689 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
690
691 /*
692 * Some fabric modules like tcm_loop can release their internally
693 * allocated I/O reference and struct se_cmd now.
694 *
695 * Fabric modules are expected to return '1' here if the se_cmd being
696 * passed is released at this point, or zero if not being released.
697 */
698 return cmd->se_tfo->check_stop_free(cmd);
699 }
700
701 static void transport_lun_remove_cmd(struct se_cmd *cmd)
702 {
703 struct se_lun *lun = cmd->se_lun;
704
705 if (!lun)
706 return;
707
708 if (cmpxchg(&cmd->lun_ref_active, true, false))
709 percpu_ref_put(&lun->lun_ref);
710 }
711
712 static void target_complete_failure_work(struct work_struct *work)
713 {
714 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
715
716 transport_generic_request_failure(cmd,
717 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
718 }
719
720 /*
721 * Used when asking transport to copy Sense Data from the underlying
722 * Linux/SCSI struct scsi_cmnd
723 */
724 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
725 {
726 struct se_device *dev = cmd->se_dev;
727
728 WARN_ON(!cmd->se_lun);
729
730 if (!dev)
731 return NULL;
732
733 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
734 return NULL;
735
736 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
737
738 pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
739 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
740 return cmd->sense_buffer;
741 }
742
743 void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
744 {
745 unsigned char *cmd_sense_buf;
746 unsigned long flags;
747
748 spin_lock_irqsave(&cmd->t_state_lock, flags);
749 cmd_sense_buf = transport_get_sense_buffer(cmd);
750 if (!cmd_sense_buf) {
751 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
752 return;
753 }
754
755 cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
756 memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
757 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
758 }
759 EXPORT_SYMBOL(transport_copy_sense_to_cmd);
760
761 static void target_handle_abort(struct se_cmd *cmd)
762 {
763 bool tas = cmd->transport_state & CMD_T_TAS;
764 bool ack_kref = cmd->se_cmd_flags & SCF_ACK_KREF;
765 int ret;
766
767 pr_debug("tag %#llx: send_abort_response = %d\n", cmd->tag, tas);
768
769 if (tas) {
770 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
771 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
772 pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
773 cmd->t_task_cdb[0], cmd->tag);
774 trace_target_cmd_complete(cmd);
775 ret = cmd->se_tfo->queue_status(cmd);
776 if (ret) {
777 transport_handle_queue_full(cmd, cmd->se_dev,
778 ret, false);
779 return;
780 }
781 } else {
782 cmd->se_tmr_req->response = TMR_FUNCTION_REJECTED;
783 cmd->se_tfo->queue_tm_rsp(cmd);
784 }
785 } else {
786 /*
787 * Allow the fabric driver to unmap any resources before
788 * releasing the descriptor via TFO->release_cmd().
789 */
790 cmd->se_tfo->aborted_task(cmd);
791 if (ack_kref)
792 WARN_ON_ONCE(target_put_sess_cmd(cmd) != 0);
793 /*
794 * To do: establish a unit attention condition on the I_T
795 * nexus associated with cmd. See also the paragraph "Aborting
796 * commands" in SAM.
797 */
798 }
799
800 WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0);
801
802 transport_lun_remove_cmd(cmd);
803
804 transport_cmd_check_stop_to_fabric(cmd);
805 }
806
807 static void target_abort_work(struct work_struct *work)
808 {
809 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
810
811 target_handle_abort(cmd);
812 }
813
814 static bool target_cmd_interrupted(struct se_cmd *cmd)
815 {
816 int post_ret;
817
818 if (cmd->transport_state & CMD_T_ABORTED) {
819 if (cmd->transport_complete_callback)
820 cmd->transport_complete_callback(cmd, false, &post_ret);
821 INIT_WORK(&cmd->work, target_abort_work);
822 queue_work(target_completion_wq, &cmd->work);
823 return true;
824 } else if (cmd->transport_state & CMD_T_STOP) {
825 if (cmd->transport_complete_callback)
826 cmd->transport_complete_callback(cmd, false, &post_ret);
827 complete_all(&cmd->t_transport_stop_comp);
828 return true;
829 }
830
831 return false;
832 }
833
834 /* May be called from interrupt context so must not sleep. */
835 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
836 {
837 int success;
838 unsigned long flags;
839
840 if (target_cmd_interrupted(cmd))
841 return;
842
843 cmd->scsi_status = scsi_status;
844
845 spin_lock_irqsave(&cmd->t_state_lock, flags);
846 switch (cmd->scsi_status) {
847 case SAM_STAT_CHECK_CONDITION:
848 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
849 success = 1;
850 else
851 success = 0;
852 break;
853 default:
854 success = 1;
855 break;
856 }
857
858 cmd->t_state = TRANSPORT_COMPLETE;
859 cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
860 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
861
862 INIT_WORK(&cmd->work, success ? target_complete_ok_work :
863 target_complete_failure_work);
864 if (cmd->se_cmd_flags & SCF_USE_CPUID)
865 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
866 else
867 queue_work(target_completion_wq, &cmd->work);
868 }
869 EXPORT_SYMBOL(target_complete_cmd);
870
871 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
872 {
873 if ((scsi_status == SAM_STAT_GOOD ||
874 cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
875 length < cmd->data_length) {
876 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
877 cmd->residual_count += cmd->data_length - length;
878 } else {
879 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
880 cmd->residual_count = cmd->data_length - length;
881 }
882
883 cmd->data_length = length;
884 }
885
886 target_complete_cmd(cmd, scsi_status);
887 }
888 EXPORT_SYMBOL(target_complete_cmd_with_length);
889
890 static void target_add_to_state_list(struct se_cmd *cmd)
891 {
892 struct se_device *dev = cmd->se_dev;
893 unsigned long flags;
894
895 spin_lock_irqsave(&dev->execute_task_lock, flags);
896 if (!cmd->state_active) {
897 list_add_tail(&cmd->state_list, &dev->state_list);
898 cmd->state_active = true;
899 }
900 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
901 }
902
903 /*
904 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
905 */
906 static void transport_write_pending_qf(struct se_cmd *cmd);
907 static void transport_complete_qf(struct se_cmd *cmd);
908
909 void target_qf_do_work(struct work_struct *work)
910 {
911 struct se_device *dev = container_of(work, struct se_device,
912 qf_work_queue);
913 LIST_HEAD(qf_cmd_list);
914 struct se_cmd *cmd, *cmd_tmp;
915
916 spin_lock_irq(&dev->qf_cmd_lock);
917 list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
918 spin_unlock_irq(&dev->qf_cmd_lock);
919
920 list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
921 list_del(&cmd->se_qf_node);
922 atomic_dec_mb(&dev->dev_qf_count);
923
924 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
925 " context: %s\n", cmd->se_tfo->fabric_name, cmd,
926 (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
927 (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
928 : "UNKNOWN");
929
930 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
931 transport_write_pending_qf(cmd);
932 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
933 cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
934 transport_complete_qf(cmd);
935 }
936 }
937
938 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
939 {
940 switch (cmd->data_direction) {
941 case DMA_NONE:
942 return "NONE";
943 case DMA_FROM_DEVICE:
944 return "READ";
945 case DMA_TO_DEVICE:
946 return "WRITE";
947 case DMA_BIDIRECTIONAL:
948 return "BIDI";
949 default:
950 break;
951 }
952
953 return "UNKNOWN";
954 }
955
956 void transport_dump_dev_state(
957 struct se_device *dev,
958 char *b,
959 int *bl)
960 {
961 *bl += sprintf(b + *bl, "Status: ");
962 if (dev->export_count)
963 *bl += sprintf(b + *bl, "ACTIVATED");
964 else
965 *bl += sprintf(b + *bl, "DEACTIVATED");
966
967 *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
968 *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
969 dev->dev_attrib.block_size,
970 dev->dev_attrib.hw_max_sectors);
971 *bl += sprintf(b + *bl, " ");
972 }
973
974 void transport_dump_vpd_proto_id(
975 struct t10_vpd *vpd,
976 unsigned char *p_buf,
977 int p_buf_len)
978 {
979 unsigned char buf[VPD_TMP_BUF_SIZE];
980 int len;
981
982 memset(buf, 0, VPD_TMP_BUF_SIZE);
983 len = sprintf(buf, "T10 VPD Protocol Identifier: ");
984
985 switch (vpd->protocol_identifier) {
986 case 0x00:
987 sprintf(buf+len, "Fibre Channel\n");
988 break;
989 case 0x10:
990 sprintf(buf+len, "Parallel SCSI\n");
991 break;
992 case 0x20:
993 sprintf(buf+len, "SSA\n");
994 break;
995 case 0x30:
996 sprintf(buf+len, "IEEE 1394\n");
997 break;
998 case 0x40:
999 sprintf(buf+len, "SCSI Remote Direct Memory Access"
1000 " Protocol\n");
1001 break;
1002 case 0x50:
1003 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
1004 break;
1005 case 0x60:
1006 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
1007 break;
1008 case 0x70:
1009 sprintf(buf+len, "Automation/Drive Interface Transport"
1010 " Protocol\n");
1011 break;
1012 case 0x80:
1013 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
1014 break;
1015 default:
1016 sprintf(buf+len, "Unknown 0x%02x\n",
1017 vpd->protocol_identifier);
1018 break;
1019 }
1020
1021 if (p_buf)
1022 strncpy(p_buf, buf, p_buf_len);
1023 else
1024 pr_debug("%s", buf);
1025 }
1026
1027 void
1028 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1029 {
1030 /*
1031 * Check if the Protocol Identifier Valid (PIV) bit is set..
1032 *
1033 * from spc3r23.pdf section 7.5.1
1034 */
1035 if (page_83[1] & 0x80) {
1036 vpd->protocol_identifier = (page_83[0] & 0xf0);
1037 vpd->protocol_identifier_set = 1;
1038 transport_dump_vpd_proto_id(vpd, NULL, 0);
1039 }
1040 }
1041 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1042
1043 int transport_dump_vpd_assoc(
1044 struct t10_vpd *vpd,
1045 unsigned char *p_buf,
1046 int p_buf_len)
1047 {
1048 unsigned char buf[VPD_TMP_BUF_SIZE];
1049 int ret = 0;
1050 int len;
1051
1052 memset(buf, 0, VPD_TMP_BUF_SIZE);
1053 len = sprintf(buf, "T10 VPD Identifier Association: ");
1054
1055 switch (vpd->association) {
1056 case 0x00:
1057 sprintf(buf+len, "addressed logical unit\n");
1058 break;
1059 case 0x10:
1060 sprintf(buf+len, "target port\n");
1061 break;
1062 case 0x20:
1063 sprintf(buf+len, "SCSI target device\n");
1064 break;
1065 default:
1066 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1067 ret = -EINVAL;
1068 break;
1069 }
1070
1071 if (p_buf)
1072 strncpy(p_buf, buf, p_buf_len);
1073 else
1074 pr_debug("%s", buf);
1075
1076 return ret;
1077 }
1078
1079 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1080 {
1081 /*
1082 * The VPD identification association..
1083 *
1084 * from spc3r23.pdf Section 7.6.3.1 Table 297
1085 */
1086 vpd->association = (page_83[1] & 0x30);
1087 return transport_dump_vpd_assoc(vpd, NULL, 0);
1088 }
1089 EXPORT_SYMBOL(transport_set_vpd_assoc);
1090
1091 int transport_dump_vpd_ident_type(
1092 struct t10_vpd *vpd,
1093 unsigned char *p_buf,
1094 int p_buf_len)
1095 {
1096 unsigned char buf[VPD_TMP_BUF_SIZE];
1097 int ret = 0;
1098 int len;
1099
1100 memset(buf, 0, VPD_TMP_BUF_SIZE);
1101 len = sprintf(buf, "T10 VPD Identifier Type: ");
1102
1103 switch (vpd->device_identifier_type) {
1104 case 0x00:
1105 sprintf(buf+len, "Vendor specific\n");
1106 break;
1107 case 0x01:
1108 sprintf(buf+len, "T10 Vendor ID based\n");
1109 break;
1110 case 0x02:
1111 sprintf(buf+len, "EUI-64 based\n");
1112 break;
1113 case 0x03:
1114 sprintf(buf+len, "NAA\n");
1115 break;
1116 case 0x04:
1117 sprintf(buf+len, "Relative target port identifier\n");
1118 break;
1119 case 0x08:
1120 sprintf(buf+len, "SCSI name string\n");
1121 break;
1122 default:
1123 sprintf(buf+len, "Unsupported: 0x%02x\n",
1124 vpd->device_identifier_type);
1125 ret = -EINVAL;
1126 break;
1127 }
1128
1129 if (p_buf) {
1130 if (p_buf_len < strlen(buf)+1)
1131 return -EINVAL;
1132 strncpy(p_buf, buf, p_buf_len);
1133 } else {
1134 pr_debug("%s", buf);
1135 }
1136
1137 return ret;
1138 }
1139
1140 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1141 {
1142 /*
1143 * The VPD identifier type..
1144 *
1145 * from spc3r23.pdf Section 7.6.3.1 Table 298
1146 */
1147 vpd->device_identifier_type = (page_83[1] & 0x0f);
1148 return transport_dump_vpd_ident_type(vpd, NULL, 0);
1149 }
1150 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1151
1152 int transport_dump_vpd_ident(
1153 struct t10_vpd *vpd,
1154 unsigned char *p_buf,
1155 int p_buf_len)
1156 {
1157 unsigned char buf[VPD_TMP_BUF_SIZE];
1158 int ret = 0;
1159
1160 memset(buf, 0, VPD_TMP_BUF_SIZE);
1161
1162 switch (vpd->device_identifier_code_set) {
1163 case 0x01: /* Binary */
1164 snprintf(buf, sizeof(buf),
1165 "T10 VPD Binary Device Identifier: %s\n",
1166 &vpd->device_identifier[0]);
1167 break;
1168 case 0x02: /* ASCII */
1169 snprintf(buf, sizeof(buf),
1170 "T10 VPD ASCII Device Identifier: %s\n",
1171 &vpd->device_identifier[0]);
1172 break;
1173 case 0x03: /* UTF-8 */
1174 snprintf(buf, sizeof(buf),
1175 "T10 VPD UTF-8 Device Identifier: %s\n",
1176 &vpd->device_identifier[0]);
1177 break;
1178 default:
1179 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1180 " 0x%02x", vpd->device_identifier_code_set);
1181 ret = -EINVAL;
1182 break;
1183 }
1184
1185 if (p_buf)
1186 strncpy(p_buf, buf, p_buf_len);
1187 else
1188 pr_debug("%s", buf);
1189
1190 return ret;
1191 }
1192
1193 int
1194 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1195 {
1196 static const char hex_str[] = "0123456789abcdef";
1197 int j = 0, i = 4; /* offset to start of the identifier */
1198
1199 /*
1200 * The VPD Code Set (encoding)
1201 *
1202 * from spc3r23.pdf Section 7.6.3.1 Table 296
1203 */
1204 vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1205 switch (vpd->device_identifier_code_set) {
1206 case 0x01: /* Binary */
1207 vpd->device_identifier[j++] =
1208 hex_str[vpd->device_identifier_type];
1209 while (i < (4 + page_83[3])) {
1210 vpd->device_identifier[j++] =
1211 hex_str[(page_83[i] & 0xf0) >> 4];
1212 vpd->device_identifier[j++] =
1213 hex_str[page_83[i] & 0x0f];
1214 i++;
1215 }
1216 break;
1217 case 0x02: /* ASCII */
1218 case 0x03: /* UTF-8 */
1219 while (i < (4 + page_83[3]))
1220 vpd->device_identifier[j++] = page_83[i++];
1221 break;
1222 default:
1223 break;
1224 }
1225
1226 return transport_dump_vpd_ident(vpd, NULL, 0);
1227 }
1228 EXPORT_SYMBOL(transport_set_vpd_ident);
1229
1230 static sense_reason_t
1231 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1232 unsigned int size)
1233 {
1234 u32 mtl;
1235
1236 if (!cmd->se_tfo->max_data_sg_nents)
1237 return TCM_NO_SENSE;
1238 /*
1239 * Check if fabric enforced maximum SGL entries per I/O descriptor
1240 * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT +
1241 * residual_count and reduce original cmd->data_length to maximum
1242 * length based on single PAGE_SIZE entry scatter-lists.
1243 */
1244 mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1245 if (cmd->data_length > mtl) {
1246 /*
1247 * If an existing CDB overflow is present, calculate new residual
1248 * based on CDB size minus fabric maximum transfer length.
1249 *
1250 * If an existing CDB underflow is present, calculate new residual
1251 * based on original cmd->data_length minus fabric maximum transfer
1252 * length.
1253 *
1254 * Otherwise, set the underflow residual based on cmd->data_length
1255 * minus fabric maximum transfer length.
1256 */
1257 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1258 cmd->residual_count = (size - mtl);
1259 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1260 u32 orig_dl = size + cmd->residual_count;
1261 cmd->residual_count = (orig_dl - mtl);
1262 } else {
1263 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1264 cmd->residual_count = (cmd->data_length - mtl);
1265 }
1266 cmd->data_length = mtl;
1267 /*
1268 * Reset sbc_check_prot() calculated protection payload
1269 * length based upon the new smaller MTL.
1270 */
1271 if (cmd->prot_length) {
1272 u32 sectors = (mtl / dev->dev_attrib.block_size);
1273 cmd->prot_length = dev->prot_length * sectors;
1274 }
1275 }
1276 return TCM_NO_SENSE;
1277 }
1278
1279 /**
1280 * target_cmd_size_check - Check whether there will be a residual.
1281 * @cmd: SCSI command.
1282 * @size: Data buffer size derived from CDB. The data buffer size provided by
1283 * the SCSI transport driver is available in @cmd->data_length.
1284 *
1285 * Compare the data buffer size from the CDB with the data buffer limit from the transport
1286 * header. Set @cmd->residual_count and SCF_OVERFLOW_BIT or SCF_UNDERFLOW_BIT if necessary.
1287 *
1288 * Note: target drivers set @cmd->data_length by calling transport_init_se_cmd().
1289 *
1290 * Return: TCM_NO_SENSE
1291 */
1292 sense_reason_t
1293 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1294 {
1295 struct se_device *dev = cmd->se_dev;
1296
1297 if (cmd->unknown_data_length) {
1298 cmd->data_length = size;
1299 } else if (size != cmd->data_length) {
1300 pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1301 " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1302 " 0x%02x\n", cmd->se_tfo->fabric_name,
1303 cmd->data_length, size, cmd->t_task_cdb[0]);
1304
1305 if (cmd->data_direction == DMA_TO_DEVICE) {
1306 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1307 pr_err_ratelimited("Rejecting underflow/overflow"
1308 " for WRITE data CDB\n");
1309 return TCM_INVALID_CDB_FIELD;
1310 }
1311 /*
1312 * Some fabric drivers like iscsi-target still expect to
1313 * always reject overflow writes. Reject this case until
1314 * full fabric driver level support for overflow writes
1315 * is introduced tree-wide.
1316 */
1317 if (size > cmd->data_length) {
1318 pr_err_ratelimited("Rejecting overflow for"
1319 " WRITE control CDB\n");
1320 return TCM_INVALID_CDB_FIELD;
1321 }
1322 }
1323 /*
1324 * Reject READ_* or WRITE_* with overflow/underflow for
1325 * type SCF_SCSI_DATA_CDB.
1326 */
1327 if (dev->dev_attrib.block_size != 512) {
1328 pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1329 " CDB on non 512-byte sector setup subsystem"
1330 " plugin: %s\n", dev->transport->name);
1331 /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1332 return TCM_INVALID_CDB_FIELD;
1333 }
1334 /*
1335 * For the overflow case keep the existing fabric provided
1336 * ->data_length. Otherwise for the underflow case, reset
1337 * ->data_length to the smaller SCSI expected data transfer
1338 * length.
1339 */
1340 if (size > cmd->data_length) {
1341 cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1342 cmd->residual_count = (size - cmd->data_length);
1343 } else {
1344 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1345 cmd->residual_count = (cmd->data_length - size);
1346 cmd->data_length = size;
1347 }
1348 }
1349
1350 return target_check_max_data_sg_nents(cmd, dev, size);
1351
1352 }
1353
1354 /*
1355 * Used by fabric modules containing a local struct se_cmd within their
1356 * fabric dependent per I/O descriptor.
1357 *
1358 * Preserves the value of @cmd->tag.
1359 */
1360 void transport_init_se_cmd(
1361 struct se_cmd *cmd,
1362 const struct target_core_fabric_ops *tfo,
1363 struct se_session *se_sess,
1364 u32 data_length,
1365 int data_direction,
1366 int task_attr,
1367 unsigned char *sense_buffer)
1368 {
1369 INIT_LIST_HEAD(&cmd->se_delayed_node);
1370 INIT_LIST_HEAD(&cmd->se_qf_node);
1371 INIT_LIST_HEAD(&cmd->se_cmd_list);
1372 INIT_LIST_HEAD(&cmd->state_list);
1373 init_completion(&cmd->t_transport_stop_comp);
1374 cmd->free_compl = NULL;
1375 cmd->abrt_compl = NULL;
1376 spin_lock_init(&cmd->t_state_lock);
1377 INIT_WORK(&cmd->work, NULL);
1378 kref_init(&cmd->cmd_kref);
1379
1380 cmd->se_tfo = tfo;
1381 cmd->se_sess = se_sess;
1382 cmd->data_length = data_length;
1383 cmd->data_direction = data_direction;
1384 cmd->sam_task_attr = task_attr;
1385 cmd->sense_buffer = sense_buffer;
1386
1387 cmd->state_active = false;
1388 }
1389 EXPORT_SYMBOL(transport_init_se_cmd);
1390
1391 static sense_reason_t
1392 transport_check_alloc_task_attr(struct se_cmd *cmd)
1393 {
1394 struct se_device *dev = cmd->se_dev;
1395
1396 /*
1397 * Check if SAM Task Attribute emulation is enabled for this
1398 * struct se_device storage object
1399 */
1400 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1401 return 0;
1402
1403 if (cmd->sam_task_attr == TCM_ACA_TAG) {
1404 pr_debug("SAM Task Attribute ACA"
1405 " emulation is not supported\n");
1406 return TCM_INVALID_CDB_FIELD;
1407 }
1408
1409 return 0;
1410 }
1411
1412 sense_reason_t
1413 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1414 {
1415 struct se_device *dev = cmd->se_dev;
1416 sense_reason_t ret;
1417
1418 /*
1419 * Ensure that the received CDB is less than the max (252 + 8) bytes
1420 * for VARIABLE_LENGTH_CMD
1421 */
1422 if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1423 pr_err("Received SCSI CDB with command_size: %d that"
1424 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1425 scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1426 return TCM_INVALID_CDB_FIELD;
1427 }
1428 /*
1429 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1430 * allocate the additional extended CDB buffer now.. Otherwise
1431 * setup the pointer from __t_task_cdb to t_task_cdb.
1432 */
1433 if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1434 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1435 GFP_KERNEL);
1436 if (!cmd->t_task_cdb) {
1437 pr_err("Unable to allocate cmd->t_task_cdb"
1438 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1439 scsi_command_size(cdb),
1440 (unsigned long)sizeof(cmd->__t_task_cdb));
1441 return TCM_OUT_OF_RESOURCES;
1442 }
1443 } else
1444 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1445 /*
1446 * Copy the original CDB into cmd->
1447 */
1448 memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1449
1450 trace_target_sequencer_start(cmd);
1451
1452 ret = dev->transport->parse_cdb(cmd);
1453 if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1454 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1455 cmd->se_tfo->fabric_name,
1456 cmd->se_sess->se_node_acl->initiatorname,
1457 cmd->t_task_cdb[0]);
1458 if (ret)
1459 return ret;
1460
1461 ret = transport_check_alloc_task_attr(cmd);
1462 if (ret)
1463 return ret;
1464
1465 cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1466 atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1467 return 0;
1468 }
1469 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1470
1471 /*
1472 * Used by fabric module frontends to queue tasks directly.
1473 * May only be used from process context.
1474 */
1475 int transport_handle_cdb_direct(
1476 struct se_cmd *cmd)
1477 {
1478 sense_reason_t ret;
1479
1480 if (!cmd->se_lun) {
1481 dump_stack();
1482 pr_err("cmd->se_lun is NULL\n");
1483 return -EINVAL;
1484 }
1485 if (in_interrupt()) {
1486 dump_stack();
1487 pr_err("transport_generic_handle_cdb cannot be called"
1488 " from interrupt context\n");
1489 return -EINVAL;
1490 }
1491 /*
1492 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1493 * outstanding descriptors are handled correctly during shutdown via
1494 * transport_wait_for_tasks()
1495 *
1496 * Also, we don't take cmd->t_state_lock here as we only expect
1497 * this to be called for initial descriptor submission.
1498 */
1499 cmd->t_state = TRANSPORT_NEW_CMD;
1500 cmd->transport_state |= CMD_T_ACTIVE;
1501
1502 /*
1503 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1504 * so follow TRANSPORT_NEW_CMD processing thread context usage
1505 * and call transport_generic_request_failure() if necessary..
1506 */
1507 ret = transport_generic_new_cmd(cmd);
1508 if (ret)
1509 transport_generic_request_failure(cmd, ret);
1510 return 0;
1511 }
1512 EXPORT_SYMBOL(transport_handle_cdb_direct);
1513
1514 sense_reason_t
1515 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1516 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1517 {
1518 if (!sgl || !sgl_count)
1519 return 0;
1520
1521 /*
1522 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1523 * scatterlists already have been set to follow what the fabric
1524 * passes for the original expected data transfer length.
1525 */
1526 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1527 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1528 " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1529 return TCM_INVALID_CDB_FIELD;
1530 }
1531
1532 cmd->t_data_sg = sgl;
1533 cmd->t_data_nents = sgl_count;
1534 cmd->t_bidi_data_sg = sgl_bidi;
1535 cmd->t_bidi_data_nents = sgl_bidi_count;
1536
1537 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1538 return 0;
1539 }
1540
1541 /**
1542 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1543 * se_cmd + use pre-allocated SGL memory.
1544 *
1545 * @se_cmd: command descriptor to submit
1546 * @se_sess: associated se_sess for endpoint
1547 * @cdb: pointer to SCSI CDB
1548 * @sense: pointer to SCSI sense buffer
1549 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1550 * @data_length: fabric expected data transfer length
1551 * @task_attr: SAM task attribute
1552 * @data_dir: DMA data direction
1553 * @flags: flags for command submission from target_sc_flags_tables
1554 * @sgl: struct scatterlist memory for unidirectional mapping
1555 * @sgl_count: scatterlist count for unidirectional mapping
1556 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1557 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1558 * @sgl_prot: struct scatterlist memory protection information
1559 * @sgl_prot_count: scatterlist count for protection information
1560 *
1561 * Task tags are supported if the caller has set @se_cmd->tag.
1562 *
1563 * Returns non zero to signal active I/O shutdown failure. All other
1564 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1565 * but still return zero here.
1566 *
1567 * This may only be called from process context, and also currently
1568 * assumes internal allocation of fabric payload buffer by target-core.
1569 */
1570 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1571 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1572 u32 data_length, int task_attr, int data_dir, int flags,
1573 struct scatterlist *sgl, u32 sgl_count,
1574 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1575 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1576 {
1577 struct se_portal_group *se_tpg;
1578 sense_reason_t rc;
1579 int ret;
1580
1581 se_tpg = se_sess->se_tpg;
1582 BUG_ON(!se_tpg);
1583 BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1584 BUG_ON(in_interrupt());
1585 /*
1586 * Initialize se_cmd for target operation. From this point
1587 * exceptions are handled by sending exception status via
1588 * target_core_fabric_ops->queue_status() callback
1589 */
1590 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1591 data_length, data_dir, task_attr, sense);
1592
1593 if (flags & TARGET_SCF_USE_CPUID)
1594 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1595 else
1596 se_cmd->cpuid = WORK_CPU_UNBOUND;
1597
1598 if (flags & TARGET_SCF_UNKNOWN_SIZE)
1599 se_cmd->unknown_data_length = 1;
1600 /*
1601 * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1602 * se_sess->sess_cmd_list. A second kref_get here is necessary
1603 * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1604 * kref_put() to happen during fabric packet acknowledgement.
1605 */
1606 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1607 if (ret)
1608 return ret;
1609 /*
1610 * Signal bidirectional data payloads to target-core
1611 */
1612 if (flags & TARGET_SCF_BIDI_OP)
1613 se_cmd->se_cmd_flags |= SCF_BIDI;
1614 /*
1615 * Locate se_lun pointer and attach it to struct se_cmd
1616 */
1617 rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1618 if (rc) {
1619 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1620 target_put_sess_cmd(se_cmd);
1621 return 0;
1622 }
1623
1624 rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1625 if (rc != 0) {
1626 transport_generic_request_failure(se_cmd, rc);
1627 return 0;
1628 }
1629
1630 /*
1631 * Save pointers for SGLs containing protection information,
1632 * if present.
1633 */
1634 if (sgl_prot_count) {
1635 se_cmd->t_prot_sg = sgl_prot;
1636 se_cmd->t_prot_nents = sgl_prot_count;
1637 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1638 }
1639
1640 /*
1641 * When a non zero sgl_count has been passed perform SGL passthrough
1642 * mapping for pre-allocated fabric memory instead of having target
1643 * core perform an internal SGL allocation..
1644 */
1645 if (sgl_count != 0) {
1646 BUG_ON(!sgl);
1647
1648 /*
1649 * A work-around for tcm_loop as some userspace code via
1650 * scsi-generic do not memset their associated read buffers,
1651 * so go ahead and do that here for type non-data CDBs. Also
1652 * note that this is currently guaranteed to be a single SGL
1653 * for this case by target core in target_setup_cmd_from_cdb()
1654 * -> transport_generic_cmd_sequencer().
1655 */
1656 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1657 se_cmd->data_direction == DMA_FROM_DEVICE) {
1658 unsigned char *buf = NULL;
1659
1660 if (sgl)
1661 buf = kmap(sg_page(sgl)) + sgl->offset;
1662
1663 if (buf) {
1664 memset(buf, 0, sgl->length);
1665 kunmap(sg_page(sgl));
1666 }
1667 }
1668
1669 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1670 sgl_bidi, sgl_bidi_count);
1671 if (rc != 0) {
1672 transport_generic_request_failure(se_cmd, rc);
1673 return 0;
1674 }
1675 }
1676
1677 /*
1678 * Check if we need to delay processing because of ALUA
1679 * Active/NonOptimized primary access state..
1680 */
1681 core_alua_check_nonop_delay(se_cmd);
1682
1683 transport_handle_cdb_direct(se_cmd);
1684 return 0;
1685 }
1686 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1687
1688 /**
1689 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1690 *
1691 * @se_cmd: command descriptor to submit
1692 * @se_sess: associated se_sess for endpoint
1693 * @cdb: pointer to SCSI CDB
1694 * @sense: pointer to SCSI sense buffer
1695 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1696 * @data_length: fabric expected data transfer length
1697 * @task_attr: SAM task attribute
1698 * @data_dir: DMA data direction
1699 * @flags: flags for command submission from target_sc_flags_tables
1700 *
1701 * Task tags are supported if the caller has set @se_cmd->tag.
1702 *
1703 * Returns non zero to signal active I/O shutdown failure. All other
1704 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1705 * but still return zero here.
1706 *
1707 * This may only be called from process context, and also currently
1708 * assumes internal allocation of fabric payload buffer by target-core.
1709 *
1710 * It also assumes interal target core SGL memory allocation.
1711 */
1712 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1713 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1714 u32 data_length, int task_attr, int data_dir, int flags)
1715 {
1716 return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1717 unpacked_lun, data_length, task_attr, data_dir,
1718 flags, NULL, 0, NULL, 0, NULL, 0);
1719 }
1720 EXPORT_SYMBOL(target_submit_cmd);
1721
1722 static void target_complete_tmr_failure(struct work_struct *work)
1723 {
1724 struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1725
1726 se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1727 se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1728
1729 transport_lun_remove_cmd(se_cmd);
1730 transport_cmd_check_stop_to_fabric(se_cmd);
1731 }
1732
1733 static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
1734 u64 *unpacked_lun)
1735 {
1736 struct se_cmd *se_cmd;
1737 unsigned long flags;
1738 bool ret = false;
1739
1740 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
1741 list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
1742 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1743 continue;
1744
1745 if (se_cmd->tag == tag) {
1746 *unpacked_lun = se_cmd->orig_fe_lun;
1747 ret = true;
1748 break;
1749 }
1750 }
1751 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
1752
1753 return ret;
1754 }
1755
1756 /**
1757 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1758 * for TMR CDBs
1759 *
1760 * @se_cmd: command descriptor to submit
1761 * @se_sess: associated se_sess for endpoint
1762 * @sense: pointer to SCSI sense buffer
1763 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1764 * @fabric_tmr_ptr: fabric context for TMR req
1765 * @tm_type: Type of TM request
1766 * @gfp: gfp type for caller
1767 * @tag: referenced task tag for TMR_ABORT_TASK
1768 * @flags: submit cmd flags
1769 *
1770 * Callable from all contexts.
1771 **/
1772
1773 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1774 unsigned char *sense, u64 unpacked_lun,
1775 void *fabric_tmr_ptr, unsigned char tm_type,
1776 gfp_t gfp, u64 tag, int flags)
1777 {
1778 struct se_portal_group *se_tpg;
1779 int ret;
1780
1781 se_tpg = se_sess->se_tpg;
1782 BUG_ON(!se_tpg);
1783
1784 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1785 0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1786 /*
1787 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1788 * allocation failure.
1789 */
1790 ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1791 if (ret < 0)
1792 return -ENOMEM;
1793
1794 if (tm_type == TMR_ABORT_TASK)
1795 se_cmd->se_tmr_req->ref_task_tag = tag;
1796
1797 /* See target_submit_cmd for commentary */
1798 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1799 if (ret) {
1800 core_tmr_release_req(se_cmd->se_tmr_req);
1801 return ret;
1802 }
1803 /*
1804 * If this is ABORT_TASK with no explicit fabric provided LUN,
1805 * go ahead and search active session tags for a match to figure
1806 * out unpacked_lun for the original se_cmd.
1807 */
1808 if (tm_type == TMR_ABORT_TASK && (flags & TARGET_SCF_LOOKUP_LUN_FROM_TAG)) {
1809 if (!target_lookup_lun_from_tag(se_sess, tag, &unpacked_lun))
1810 goto failure;
1811 }
1812
1813 ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1814 if (ret)
1815 goto failure;
1816
1817 transport_generic_handle_tmr(se_cmd);
1818 return 0;
1819
1820 /*
1821 * For callback during failure handling, push this work off
1822 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1823 */
1824 failure:
1825 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1826 schedule_work(&se_cmd->work);
1827 return 0;
1828 }
1829 EXPORT_SYMBOL(target_submit_tmr);
1830
1831 /*
1832 * Handle SAM-esque emulation for generic transport request failures.
1833 */
1834 void transport_generic_request_failure(struct se_cmd *cmd,
1835 sense_reason_t sense_reason)
1836 {
1837 int ret = 0, post_ret;
1838
1839 pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
1840 sense_reason);
1841 target_show_cmd("-----[ ", cmd);
1842
1843 /*
1844 * For SAM Task Attribute emulation for failed struct se_cmd
1845 */
1846 transport_complete_task_attr(cmd);
1847
1848 if (cmd->transport_complete_callback)
1849 cmd->transport_complete_callback(cmd, false, &post_ret);
1850
1851 if (cmd->transport_state & CMD_T_ABORTED) {
1852 INIT_WORK(&cmd->work, target_abort_work);
1853 queue_work(target_completion_wq, &cmd->work);
1854 return;
1855 }
1856
1857 switch (sense_reason) {
1858 case TCM_NON_EXISTENT_LUN:
1859 case TCM_UNSUPPORTED_SCSI_OPCODE:
1860 case TCM_INVALID_CDB_FIELD:
1861 case TCM_INVALID_PARAMETER_LIST:
1862 case TCM_PARAMETER_LIST_LENGTH_ERROR:
1863 case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1864 case TCM_UNKNOWN_MODE_PAGE:
1865 case TCM_WRITE_PROTECTED:
1866 case TCM_ADDRESS_OUT_OF_RANGE:
1867 case TCM_CHECK_CONDITION_ABORT_CMD:
1868 case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1869 case TCM_CHECK_CONDITION_NOT_READY:
1870 case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1871 case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1872 case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1873 case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1874 case TCM_TOO_MANY_TARGET_DESCS:
1875 case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
1876 case TCM_TOO_MANY_SEGMENT_DESCS:
1877 case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
1878 break;
1879 case TCM_OUT_OF_RESOURCES:
1880 cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
1881 goto queue_status;
1882 case TCM_LUN_BUSY:
1883 cmd->scsi_status = SAM_STAT_BUSY;
1884 goto queue_status;
1885 case TCM_RESERVATION_CONFLICT:
1886 /*
1887 * No SENSE Data payload for this case, set SCSI Status
1888 * and queue the response to $FABRIC_MOD.
1889 *
1890 * Uses linux/include/scsi/scsi.h SAM status codes defs
1891 */
1892 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1893 /*
1894 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1895 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1896 * CONFLICT STATUS.
1897 *
1898 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1899 */
1900 if (cmd->se_sess &&
1901 cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl
1902 == TARGET_UA_INTLCK_CTRL_ESTABLISH_UA) {
1903 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1904 cmd->orig_fe_lun, 0x2C,
1905 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1906 }
1907
1908 goto queue_status;
1909 default:
1910 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1911 cmd->t_task_cdb[0], sense_reason);
1912 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1913 break;
1914 }
1915
1916 ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1917 if (ret)
1918 goto queue_full;
1919
1920 check_stop:
1921 transport_lun_remove_cmd(cmd);
1922 transport_cmd_check_stop_to_fabric(cmd);
1923 return;
1924
1925 queue_status:
1926 trace_target_cmd_complete(cmd);
1927 ret = cmd->se_tfo->queue_status(cmd);
1928 if (!ret)
1929 goto check_stop;
1930 queue_full:
1931 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
1932 }
1933 EXPORT_SYMBOL(transport_generic_request_failure);
1934
1935 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1936 {
1937 sense_reason_t ret;
1938
1939 if (!cmd->execute_cmd) {
1940 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1941 goto err;
1942 }
1943 if (do_checks) {
1944 /*
1945 * Check for an existing UNIT ATTENTION condition after
1946 * target_handle_task_attr() has done SAM task attr
1947 * checking, and possibly have already defered execution
1948 * out to target_restart_delayed_cmds() context.
1949 */
1950 ret = target_scsi3_ua_check(cmd);
1951 if (ret)
1952 goto err;
1953
1954 ret = target_alua_state_check(cmd);
1955 if (ret)
1956 goto err;
1957
1958 ret = target_check_reservation(cmd);
1959 if (ret) {
1960 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1961 goto err;
1962 }
1963 }
1964
1965 ret = cmd->execute_cmd(cmd);
1966 if (!ret)
1967 return;
1968 err:
1969 spin_lock_irq(&cmd->t_state_lock);
1970 cmd->transport_state &= ~CMD_T_SENT;
1971 spin_unlock_irq(&cmd->t_state_lock);
1972
1973 transport_generic_request_failure(cmd, ret);
1974 }
1975
1976 static int target_write_prot_action(struct se_cmd *cmd)
1977 {
1978 u32 sectors;
1979 /*
1980 * Perform WRITE_INSERT of PI using software emulation when backend
1981 * device has PI enabled, if the transport has not already generated
1982 * PI using hardware WRITE_INSERT offload.
1983 */
1984 switch (cmd->prot_op) {
1985 case TARGET_PROT_DOUT_INSERT:
1986 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1987 sbc_dif_generate(cmd);
1988 break;
1989 case TARGET_PROT_DOUT_STRIP:
1990 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1991 break;
1992
1993 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1994 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1995 sectors, 0, cmd->t_prot_sg, 0);
1996 if (unlikely(cmd->pi_err)) {
1997 spin_lock_irq(&cmd->t_state_lock);
1998 cmd->transport_state &= ~CMD_T_SENT;
1999 spin_unlock_irq(&cmd->t_state_lock);
2000 transport_generic_request_failure(cmd, cmd->pi_err);
2001 return -1;
2002 }
2003 break;
2004 default:
2005 break;
2006 }
2007
2008 return 0;
2009 }
2010
2011 static bool target_handle_task_attr(struct se_cmd *cmd)
2012 {
2013 struct se_device *dev = cmd->se_dev;
2014
2015 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2016 return false;
2017
2018 cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
2019
2020 /*
2021 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
2022 * to allow the passed struct se_cmd list of tasks to the front of the list.
2023 */
2024 switch (cmd->sam_task_attr) {
2025 case TCM_HEAD_TAG:
2026 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
2027 cmd->t_task_cdb[0]);
2028 return false;
2029 case TCM_ORDERED_TAG:
2030 atomic_inc_mb(&dev->dev_ordered_sync);
2031
2032 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
2033 cmd->t_task_cdb[0]);
2034
2035 /*
2036 * Execute an ORDERED command if no other older commands
2037 * exist that need to be completed first.
2038 */
2039 if (!atomic_read(&dev->simple_cmds))
2040 return false;
2041 break;
2042 default:
2043 /*
2044 * For SIMPLE and UNTAGGED Task Attribute commands
2045 */
2046 atomic_inc_mb(&dev->simple_cmds);
2047 break;
2048 }
2049
2050 if (atomic_read(&dev->dev_ordered_sync) == 0)
2051 return false;
2052
2053 spin_lock(&dev->delayed_cmd_lock);
2054 list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
2055 spin_unlock(&dev->delayed_cmd_lock);
2056
2057 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
2058 cmd->t_task_cdb[0], cmd->sam_task_attr);
2059 return true;
2060 }
2061
2062 void target_execute_cmd(struct se_cmd *cmd)
2063 {
2064 /*
2065 * Determine if frontend context caller is requesting the stopping of
2066 * this command for frontend exceptions.
2067 *
2068 * If the received CDB has already been aborted stop processing it here.
2069 */
2070 if (target_cmd_interrupted(cmd))
2071 return;
2072
2073 spin_lock_irq(&cmd->t_state_lock);
2074 cmd->t_state = TRANSPORT_PROCESSING;
2075 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
2076 spin_unlock_irq(&cmd->t_state_lock);
2077
2078 if (target_write_prot_action(cmd))
2079 return;
2080
2081 if (target_handle_task_attr(cmd)) {
2082 spin_lock_irq(&cmd->t_state_lock);
2083 cmd->transport_state &= ~CMD_T_SENT;
2084 spin_unlock_irq(&cmd->t_state_lock);
2085 return;
2086 }
2087
2088 __target_execute_cmd(cmd, true);
2089 }
2090 EXPORT_SYMBOL(target_execute_cmd);
2091
2092 /*
2093 * Process all commands up to the last received ORDERED task attribute which
2094 * requires another blocking boundary
2095 */
2096 static void target_restart_delayed_cmds(struct se_device *dev)
2097 {
2098 for (;;) {
2099 struct se_cmd *cmd;
2100
2101 spin_lock(&dev->delayed_cmd_lock);
2102 if (list_empty(&dev->delayed_cmd_list)) {
2103 spin_unlock(&dev->delayed_cmd_lock);
2104 break;
2105 }
2106
2107 cmd = list_entry(dev->delayed_cmd_list.next,
2108 struct se_cmd, se_delayed_node);
2109 list_del(&cmd->se_delayed_node);
2110 spin_unlock(&dev->delayed_cmd_lock);
2111
2112 cmd->transport_state |= CMD_T_SENT;
2113
2114 __target_execute_cmd(cmd, true);
2115
2116 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
2117 break;
2118 }
2119 }
2120
2121 /*
2122 * Called from I/O completion to determine which dormant/delayed
2123 * and ordered cmds need to have their tasks added to the execution queue.
2124 */
2125 static void transport_complete_task_attr(struct se_cmd *cmd)
2126 {
2127 struct se_device *dev = cmd->se_dev;
2128
2129 if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2130 return;
2131
2132 if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2133 goto restart;
2134
2135 if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
2136 atomic_dec_mb(&dev->simple_cmds);
2137 dev->dev_cur_ordered_id++;
2138 } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
2139 dev->dev_cur_ordered_id++;
2140 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
2141 dev->dev_cur_ordered_id);
2142 } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2143 atomic_dec_mb(&dev->dev_ordered_sync);
2144
2145 dev->dev_cur_ordered_id++;
2146 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
2147 dev->dev_cur_ordered_id);
2148 }
2149 cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2150
2151 restart:
2152 target_restart_delayed_cmds(dev);
2153 }
2154
2155 static void transport_complete_qf(struct se_cmd *cmd)
2156 {
2157 int ret = 0;
2158
2159 transport_complete_task_attr(cmd);
2160 /*
2161 * If a fabric driver ->write_pending() or ->queue_data_in() callback
2162 * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2163 * the same callbacks should not be retried. Return CHECK_CONDITION
2164 * if a scsi_status is not already set.
2165 *
2166 * If a fabric driver ->queue_status() has returned non zero, always
2167 * keep retrying no matter what..
2168 */
2169 if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2170 if (cmd->scsi_status)
2171 goto queue_status;
2172
2173 translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2174 goto queue_status;
2175 }
2176
2177 /*
2178 * Check if we need to send a sense buffer from
2179 * the struct se_cmd in question. We do NOT want
2180 * to take this path of the IO has been marked as
2181 * needing to be treated like a "normal read". This
2182 * is the case if it's a tape read, and either the
2183 * FM, EOM, or ILI bits are set, but there is no
2184 * sense data.
2185 */
2186 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2187 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2188 goto queue_status;
2189
2190 switch (cmd->data_direction) {
2191 case DMA_FROM_DEVICE:
2192 /* queue status if not treating this as a normal read */
2193 if (cmd->scsi_status &&
2194 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2195 goto queue_status;
2196
2197 trace_target_cmd_complete(cmd);
2198 ret = cmd->se_tfo->queue_data_in(cmd);
2199 break;
2200 case DMA_TO_DEVICE:
2201 if (cmd->se_cmd_flags & SCF_BIDI) {
2202 ret = cmd->se_tfo->queue_data_in(cmd);
2203 break;
2204 }
2205 /* fall through */
2206 case DMA_NONE:
2207 queue_status:
2208 trace_target_cmd_complete(cmd);
2209 ret = cmd->se_tfo->queue_status(cmd);
2210 break;
2211 default:
2212 break;
2213 }
2214
2215 if (ret < 0) {
2216 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2217 return;
2218 }
2219 transport_lun_remove_cmd(cmd);
2220 transport_cmd_check_stop_to_fabric(cmd);
2221 }
2222
2223 static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2224 int err, bool write_pending)
2225 {
2226 /*
2227 * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2228 * ->queue_data_in() callbacks from new process context.
2229 *
2230 * Otherwise for other errors, transport_complete_qf() will send
2231 * CHECK_CONDITION via ->queue_status() instead of attempting to
2232 * retry associated fabric driver data-transfer callbacks.
2233 */
2234 if (err == -EAGAIN || err == -ENOMEM) {
2235 cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2236 TRANSPORT_COMPLETE_QF_OK;
2237 } else {
2238 pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2239 cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2240 }
2241
2242 spin_lock_irq(&dev->qf_cmd_lock);
2243 list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2244 atomic_inc_mb(&dev->dev_qf_count);
2245 spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2246
2247 schedule_work(&cmd->se_dev->qf_work_queue);
2248 }
2249
2250 static bool target_read_prot_action(struct se_cmd *cmd)
2251 {
2252 switch (cmd->prot_op) {
2253 case TARGET_PROT_DIN_STRIP:
2254 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2255 u32 sectors = cmd->data_length >>
2256 ilog2(cmd->se_dev->dev_attrib.block_size);
2257
2258 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2259 sectors, 0, cmd->t_prot_sg,
2260 0);
2261 if (cmd->pi_err)
2262 return true;
2263 }
2264 break;
2265 case TARGET_PROT_DIN_INSERT:
2266 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2267 break;
2268
2269 sbc_dif_generate(cmd);
2270 break;
2271 default:
2272 break;
2273 }
2274
2275 return false;
2276 }
2277
2278 static void target_complete_ok_work(struct work_struct *work)
2279 {
2280 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2281 int ret;
2282
2283 /*
2284 * Check if we need to move delayed/dormant tasks from cmds on the
2285 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2286 * Attribute.
2287 */
2288 transport_complete_task_attr(cmd);
2289
2290 /*
2291 * Check to schedule QUEUE_FULL work, or execute an existing
2292 * cmd->transport_qf_callback()
2293 */
2294 if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2295 schedule_work(&cmd->se_dev->qf_work_queue);
2296
2297 /*
2298 * Check if we need to send a sense buffer from
2299 * the struct se_cmd in question. We do NOT want
2300 * to take this path of the IO has been marked as
2301 * needing to be treated like a "normal read". This
2302 * is the case if it's a tape read, and either the
2303 * FM, EOM, or ILI bits are set, but there is no
2304 * sense data.
2305 */
2306 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2307 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2308 WARN_ON(!cmd->scsi_status);
2309 ret = transport_send_check_condition_and_sense(
2310 cmd, 0, 1);
2311 if (ret)
2312 goto queue_full;
2313
2314 transport_lun_remove_cmd(cmd);
2315 transport_cmd_check_stop_to_fabric(cmd);
2316 return;
2317 }
2318 /*
2319 * Check for a callback, used by amongst other things
2320 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2321 */
2322 if (cmd->transport_complete_callback) {
2323 sense_reason_t rc;
2324 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2325 bool zero_dl = !(cmd->data_length);
2326 int post_ret = 0;
2327
2328 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2329 if (!rc && !post_ret) {
2330 if (caw && zero_dl)
2331 goto queue_rsp;
2332
2333 return;
2334 } else if (rc) {
2335 ret = transport_send_check_condition_and_sense(cmd,
2336 rc, 0);
2337 if (ret)
2338 goto queue_full;
2339
2340 transport_lun_remove_cmd(cmd);
2341 transport_cmd_check_stop_to_fabric(cmd);
2342 return;
2343 }
2344 }
2345
2346 queue_rsp:
2347 switch (cmd->data_direction) {
2348 case DMA_FROM_DEVICE:
2349 /*
2350 * if this is a READ-type IO, but SCSI status
2351 * is set, then skip returning data and just
2352 * return the status -- unless this IO is marked
2353 * as needing to be treated as a normal read,
2354 * in which case we want to go ahead and return
2355 * the data. This happens, for example, for tape
2356 * reads with the FM, EOM, or ILI bits set, with
2357 * no sense data.
2358 */
2359 if (cmd->scsi_status &&
2360 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2361 goto queue_status;
2362
2363 atomic_long_add(cmd->data_length,
2364 &cmd->se_lun->lun_stats.tx_data_octets);
2365 /*
2366 * Perform READ_STRIP of PI using software emulation when
2367 * backend had PI enabled, if the transport will not be
2368 * performing hardware READ_STRIP offload.
2369 */
2370 if (target_read_prot_action(cmd)) {
2371 ret = transport_send_check_condition_and_sense(cmd,
2372 cmd->pi_err, 0);
2373 if (ret)
2374 goto queue_full;
2375
2376 transport_lun_remove_cmd(cmd);
2377 transport_cmd_check_stop_to_fabric(cmd);
2378 return;
2379 }
2380
2381 trace_target_cmd_complete(cmd);
2382 ret = cmd->se_tfo->queue_data_in(cmd);
2383 if (ret)
2384 goto queue_full;
2385 break;
2386 case DMA_TO_DEVICE:
2387 atomic_long_add(cmd->data_length,
2388 &cmd->se_lun->lun_stats.rx_data_octets);
2389 /*
2390 * Check if we need to send READ payload for BIDI-COMMAND
2391 */
2392 if (cmd->se_cmd_flags & SCF_BIDI) {
2393 atomic_long_add(cmd->data_length,
2394 &cmd->se_lun->lun_stats.tx_data_octets);
2395 ret = cmd->se_tfo->queue_data_in(cmd);
2396 if (ret)
2397 goto queue_full;
2398 break;
2399 }
2400 /* fall through */
2401 case DMA_NONE:
2402 queue_status:
2403 trace_target_cmd_complete(cmd);
2404 ret = cmd->se_tfo->queue_status(cmd);
2405 if (ret)
2406 goto queue_full;
2407 break;
2408 default:
2409 break;
2410 }
2411
2412 transport_lun_remove_cmd(cmd);
2413 transport_cmd_check_stop_to_fabric(cmd);
2414 return;
2415
2416 queue_full:
2417 pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2418 " data_direction: %d\n", cmd, cmd->data_direction);
2419
2420 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2421 }
2422
2423 void target_free_sgl(struct scatterlist *sgl, int nents)
2424 {
2425 sgl_free_n_order(sgl, nents, 0);
2426 }
2427 EXPORT_SYMBOL(target_free_sgl);
2428
2429 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2430 {
2431 /*
2432 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2433 * emulation, and free + reset pointers if necessary..
2434 */
2435 if (!cmd->t_data_sg_orig)
2436 return;
2437
2438 kfree(cmd->t_data_sg);
2439 cmd->t_data_sg = cmd->t_data_sg_orig;
2440 cmd->t_data_sg_orig = NULL;
2441 cmd->t_data_nents = cmd->t_data_nents_orig;
2442 cmd->t_data_nents_orig = 0;
2443 }
2444
2445 static inline void transport_free_pages(struct se_cmd *cmd)
2446 {
2447 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2448 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2449 cmd->t_prot_sg = NULL;
2450 cmd->t_prot_nents = 0;
2451 }
2452
2453 if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2454 /*
2455 * Release special case READ buffer payload required for
2456 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2457 */
2458 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2459 target_free_sgl(cmd->t_bidi_data_sg,
2460 cmd->t_bidi_data_nents);
2461 cmd->t_bidi_data_sg = NULL;
2462 cmd->t_bidi_data_nents = 0;
2463 }
2464 transport_reset_sgl_orig(cmd);
2465 return;
2466 }
2467 transport_reset_sgl_orig(cmd);
2468
2469 target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2470 cmd->t_data_sg = NULL;
2471 cmd->t_data_nents = 0;
2472
2473 target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2474 cmd->t_bidi_data_sg = NULL;
2475 cmd->t_bidi_data_nents = 0;
2476 }
2477
2478 void *transport_kmap_data_sg(struct se_cmd *cmd)
2479 {
2480 struct scatterlist *sg = cmd->t_data_sg;
2481 struct page **pages;
2482 int i;
2483
2484 /*
2485 * We need to take into account a possible offset here for fabrics like
2486 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2487 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2488 */
2489 if (!cmd->t_data_nents)
2490 return NULL;
2491
2492 BUG_ON(!sg);
2493 if (cmd->t_data_nents == 1)
2494 return kmap(sg_page(sg)) + sg->offset;
2495
2496 /* >1 page. use vmap */
2497 pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2498 if (!pages)
2499 return NULL;
2500
2501 /* convert sg[] to pages[] */
2502 for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2503 pages[i] = sg_page(sg);
2504 }
2505
2506 cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
2507 kfree(pages);
2508 if (!cmd->t_data_vmap)
2509 return NULL;
2510
2511 return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2512 }
2513 EXPORT_SYMBOL(transport_kmap_data_sg);
2514
2515 void transport_kunmap_data_sg(struct se_cmd *cmd)
2516 {
2517 if (!cmd->t_data_nents) {
2518 return;
2519 } else if (cmd->t_data_nents == 1) {
2520 kunmap(sg_page(cmd->t_data_sg));
2521 return;
2522 }
2523
2524 vunmap(cmd->t_data_vmap);
2525 cmd->t_data_vmap = NULL;
2526 }
2527 EXPORT_SYMBOL(transport_kunmap_data_sg);
2528
2529 int
2530 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2531 bool zero_page, bool chainable)
2532 {
2533 gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2534
2535 *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2536 return *sgl ? 0 : -ENOMEM;
2537 }
2538 EXPORT_SYMBOL(target_alloc_sgl);
2539
2540 /*
2541 * Allocate any required resources to execute the command. For writes we
2542 * might not have the payload yet, so notify the fabric via a call to
2543 * ->write_pending instead. Otherwise place it on the execution queue.
2544 */
2545 sense_reason_t
2546 transport_generic_new_cmd(struct se_cmd *cmd)
2547 {
2548 unsigned long flags;
2549 int ret = 0;
2550 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2551
2552 if (cmd->prot_op != TARGET_PROT_NORMAL &&
2553 !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2554 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2555 cmd->prot_length, true, false);
2556 if (ret < 0)
2557 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2558 }
2559
2560 /*
2561 * Determine if the TCM fabric module has already allocated physical
2562 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2563 * beforehand.
2564 */
2565 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2566 cmd->data_length) {
2567
2568 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2569 (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2570 u32 bidi_length;
2571
2572 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2573 bidi_length = cmd->t_task_nolb *
2574 cmd->se_dev->dev_attrib.block_size;
2575 else
2576 bidi_length = cmd->data_length;
2577
2578 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2579 &cmd->t_bidi_data_nents,
2580 bidi_length, zero_flag, false);
2581 if (ret < 0)
2582 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2583 }
2584
2585 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2586 cmd->data_length, zero_flag, false);
2587 if (ret < 0)
2588 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2589 } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2590 cmd->data_length) {
2591 /*
2592 * Special case for COMPARE_AND_WRITE with fabrics
2593 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2594 */
2595 u32 caw_length = cmd->t_task_nolb *
2596 cmd->se_dev->dev_attrib.block_size;
2597
2598 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2599 &cmd->t_bidi_data_nents,
2600 caw_length, zero_flag, false);
2601 if (ret < 0)
2602 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2603 }
2604 /*
2605 * If this command is not a write we can execute it right here,
2606 * for write buffers we need to notify the fabric driver first
2607 * and let it call back once the write buffers are ready.
2608 */
2609 target_add_to_state_list(cmd);
2610 if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2611 target_execute_cmd(cmd);
2612 return 0;
2613 }
2614
2615 spin_lock_irqsave(&cmd->t_state_lock, flags);
2616 cmd->t_state = TRANSPORT_WRITE_PENDING;
2617 /*
2618 * Determine if frontend context caller is requesting the stopping of
2619 * this command for frontend exceptions.
2620 */
2621 if (cmd->transport_state & CMD_T_STOP &&
2622 !cmd->se_tfo->write_pending_must_be_called) {
2623 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2624 __func__, __LINE__, cmd->tag);
2625
2626 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2627
2628 complete_all(&cmd->t_transport_stop_comp);
2629 return 0;
2630 }
2631 cmd->transport_state &= ~CMD_T_ACTIVE;
2632 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2633
2634 ret = cmd->se_tfo->write_pending(cmd);
2635 if (ret)
2636 goto queue_full;
2637
2638 return 0;
2639
2640 queue_full:
2641 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2642 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2643 return 0;
2644 }
2645 EXPORT_SYMBOL(transport_generic_new_cmd);
2646
2647 static void transport_write_pending_qf(struct se_cmd *cmd)
2648 {
2649 unsigned long flags;
2650 int ret;
2651 bool stop;
2652
2653 spin_lock_irqsave(&cmd->t_state_lock, flags);
2654 stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2655 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2656
2657 if (stop) {
2658 pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2659 __func__, __LINE__, cmd->tag);
2660 complete_all(&cmd->t_transport_stop_comp);
2661 return;
2662 }
2663
2664 ret = cmd->se_tfo->write_pending(cmd);
2665 if (ret) {
2666 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2667 cmd);
2668 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2669 }
2670 }
2671
2672 static bool
2673 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2674 unsigned long *flags);
2675
2676 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2677 {
2678 unsigned long flags;
2679
2680 spin_lock_irqsave(&cmd->t_state_lock, flags);
2681 __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2682 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2683 }
2684
2685 /*
2686 * Call target_put_sess_cmd() and wait until target_release_cmd_kref(@cmd) has
2687 * finished.
2688 */
2689 void target_put_cmd_and_wait(struct se_cmd *cmd)
2690 {
2691 DECLARE_COMPLETION_ONSTACK(compl);
2692
2693 WARN_ON_ONCE(cmd->abrt_compl);
2694 cmd->abrt_compl = &compl;
2695 target_put_sess_cmd(cmd);
2696 wait_for_completion(&compl);
2697 }
2698
2699 /*
2700 * This function is called by frontend drivers after processing of a command
2701 * has finished.
2702 *
2703 * The protocol for ensuring that either the regular frontend command
2704 * processing flow or target_handle_abort() code drops one reference is as
2705 * follows:
2706 * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
2707 * the frontend driver to call this function synchronously or asynchronously.
2708 * That will cause one reference to be dropped.
2709 * - During regular command processing the target core sets CMD_T_COMPLETE
2710 * before invoking one of the .queue_*() functions.
2711 * - The code that aborts commands skips commands and TMFs for which
2712 * CMD_T_COMPLETE has been set.
2713 * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
2714 * commands that will be aborted.
2715 * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
2716 * transport_generic_free_cmd() skips its call to target_put_sess_cmd().
2717 * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
2718 * be called and will drop a reference.
2719 * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
2720 * will be called. target_handle_abort() will drop the final reference.
2721 */
2722 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2723 {
2724 DECLARE_COMPLETION_ONSTACK(compl);
2725 int ret = 0;
2726 bool aborted = false, tas = false;
2727
2728 if (wait_for_tasks)
2729 target_wait_free_cmd(cmd, &aborted, &tas);
2730
2731 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
2732 /*
2733 * Handle WRITE failure case where transport_generic_new_cmd()
2734 * has already added se_cmd to state_list, but fabric has
2735 * failed command before I/O submission.
2736 */
2737 if (cmd->state_active)
2738 target_remove_from_state_list(cmd);
2739
2740 if (cmd->se_lun)
2741 transport_lun_remove_cmd(cmd);
2742 }
2743 if (aborted)
2744 cmd->free_compl = &compl;
2745 ret = target_put_sess_cmd(cmd);
2746 if (aborted) {
2747 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2748 wait_for_completion(&compl);
2749 ret = 1;
2750 }
2751 return ret;
2752 }
2753 EXPORT_SYMBOL(transport_generic_free_cmd);
2754
2755 /**
2756 * target_get_sess_cmd - Add command to active ->sess_cmd_list
2757 * @se_cmd: command descriptor to add
2758 * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
2759 */
2760 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2761 {
2762 struct se_session *se_sess = se_cmd->se_sess;
2763 unsigned long flags;
2764 int ret = 0;
2765
2766 /*
2767 * Add a second kref if the fabric caller is expecting to handle
2768 * fabric acknowledgement that requires two target_put_sess_cmd()
2769 * invocations before se_cmd descriptor release.
2770 */
2771 if (ack_kref) {
2772 if (!kref_get_unless_zero(&se_cmd->cmd_kref))
2773 return -EINVAL;
2774
2775 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2776 }
2777
2778 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2779 if (se_sess->sess_tearing_down) {
2780 ret = -ESHUTDOWN;
2781 goto out;
2782 }
2783 list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2784 percpu_ref_get(&se_sess->cmd_count);
2785 out:
2786 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2787
2788 if (ret && ack_kref)
2789 target_put_sess_cmd(se_cmd);
2790
2791 return ret;
2792 }
2793 EXPORT_SYMBOL(target_get_sess_cmd);
2794
2795 static void target_free_cmd_mem(struct se_cmd *cmd)
2796 {
2797 transport_free_pages(cmd);
2798
2799 if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2800 core_tmr_release_req(cmd->se_tmr_req);
2801 if (cmd->t_task_cdb != cmd->__t_task_cdb)
2802 kfree(cmd->t_task_cdb);
2803 }
2804
2805 static void target_release_cmd_kref(struct kref *kref)
2806 {
2807 struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2808 struct se_session *se_sess = se_cmd->se_sess;
2809 struct completion *free_compl = se_cmd->free_compl;
2810 struct completion *abrt_compl = se_cmd->abrt_compl;
2811 unsigned long flags;
2812
2813 if (se_sess) {
2814 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2815 list_del_init(&se_cmd->se_cmd_list);
2816 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2817 }
2818
2819 target_free_cmd_mem(se_cmd);
2820 se_cmd->se_tfo->release_cmd(se_cmd);
2821 if (free_compl)
2822 complete(free_compl);
2823 if (abrt_compl)
2824 complete(abrt_compl);
2825
2826 percpu_ref_put(&se_sess->cmd_count);
2827 }
2828
2829 /**
2830 * target_put_sess_cmd - decrease the command reference count
2831 * @se_cmd: command to drop a reference from
2832 *
2833 * Returns 1 if and only if this target_put_sess_cmd() call caused the
2834 * refcount to drop to zero. Returns zero otherwise.
2835 */
2836 int target_put_sess_cmd(struct se_cmd *se_cmd)
2837 {
2838 return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2839 }
2840 EXPORT_SYMBOL(target_put_sess_cmd);
2841
2842 static const char *data_dir_name(enum dma_data_direction d)
2843 {
2844 switch (d) {
2845 case DMA_BIDIRECTIONAL: return "BIDI";
2846 case DMA_TO_DEVICE: return "WRITE";
2847 case DMA_FROM_DEVICE: return "READ";
2848 case DMA_NONE: return "NONE";
2849 }
2850
2851 return "(?)";
2852 }
2853
2854 static const char *cmd_state_name(enum transport_state_table t)
2855 {
2856 switch (t) {
2857 case TRANSPORT_NO_STATE: return "NO_STATE";
2858 case TRANSPORT_NEW_CMD: return "NEW_CMD";
2859 case TRANSPORT_WRITE_PENDING: return "WRITE_PENDING";
2860 case TRANSPORT_PROCESSING: return "PROCESSING";
2861 case TRANSPORT_COMPLETE: return "COMPLETE";
2862 case TRANSPORT_ISTATE_PROCESSING:
2863 return "ISTATE_PROCESSING";
2864 case TRANSPORT_COMPLETE_QF_WP: return "COMPLETE_QF_WP";
2865 case TRANSPORT_COMPLETE_QF_OK: return "COMPLETE_QF_OK";
2866 case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR";
2867 }
2868
2869 return "(?)";
2870 }
2871
2872 static void target_append_str(char **str, const char *txt)
2873 {
2874 char *prev = *str;
2875
2876 *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
2877 kstrdup(txt, GFP_ATOMIC);
2878 kfree(prev);
2879 }
2880
2881 /*
2882 * Convert a transport state bitmask into a string. The caller is
2883 * responsible for freeing the returned pointer.
2884 */
2885 static char *target_ts_to_str(u32 ts)
2886 {
2887 char *str = NULL;
2888
2889 if (ts & CMD_T_ABORTED)
2890 target_append_str(&str, "aborted");
2891 if (ts & CMD_T_ACTIVE)
2892 target_append_str(&str, "active");
2893 if (ts & CMD_T_COMPLETE)
2894 target_append_str(&str, "complete");
2895 if (ts & CMD_T_SENT)
2896 target_append_str(&str, "sent");
2897 if (ts & CMD_T_STOP)
2898 target_append_str(&str, "stop");
2899 if (ts & CMD_T_FABRIC_STOP)
2900 target_append_str(&str, "fabric_stop");
2901
2902 return str;
2903 }
2904
2905 static const char *target_tmf_name(enum tcm_tmreq_table tmf)
2906 {
2907 switch (tmf) {
2908 case TMR_ABORT_TASK: return "ABORT_TASK";
2909 case TMR_ABORT_TASK_SET: return "ABORT_TASK_SET";
2910 case TMR_CLEAR_ACA: return "CLEAR_ACA";
2911 case TMR_CLEAR_TASK_SET: return "CLEAR_TASK_SET";
2912 case TMR_LUN_RESET: return "LUN_RESET";
2913 case TMR_TARGET_WARM_RESET: return "TARGET_WARM_RESET";
2914 case TMR_TARGET_COLD_RESET: return "TARGET_COLD_RESET";
2915 case TMR_UNKNOWN: break;
2916 }
2917 return "(?)";
2918 }
2919
2920 void target_show_cmd(const char *pfx, struct se_cmd *cmd)
2921 {
2922 char *ts_str = target_ts_to_str(cmd->transport_state);
2923 const u8 *cdb = cmd->t_task_cdb;
2924 struct se_tmr_req *tmf = cmd->se_tmr_req;
2925
2926 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2927 pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
2928 pfx, cdb[0], cdb[1], cmd->tag,
2929 data_dir_name(cmd->data_direction),
2930 cmd->se_tfo->get_cmd_state(cmd),
2931 cmd_state_name(cmd->t_state), cmd->data_length,
2932 kref_read(&cmd->cmd_kref), ts_str);
2933 } else {
2934 pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
2935 pfx, target_tmf_name(tmf->function), cmd->tag,
2936 tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
2937 cmd_state_name(cmd->t_state),
2938 kref_read(&cmd->cmd_kref), ts_str);
2939 }
2940 kfree(ts_str);
2941 }
2942 EXPORT_SYMBOL(target_show_cmd);
2943
2944 /**
2945 * target_sess_cmd_list_set_waiting - Set sess_tearing_down so no new commands are queued.
2946 * @se_sess: session to flag
2947 */
2948 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2949 {
2950 unsigned long flags;
2951
2952 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2953 se_sess->sess_tearing_down = 1;
2954 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2955
2956 percpu_ref_kill(&se_sess->cmd_count);
2957 }
2958 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2959
2960 /**
2961 * target_wait_for_sess_cmds - Wait for outstanding commands
2962 * @se_sess: session to wait for active I/O
2963 */
2964 void target_wait_for_sess_cmds(struct se_session *se_sess)
2965 {
2966 struct se_cmd *cmd;
2967 int ret;
2968
2969 WARN_ON_ONCE(!se_sess->sess_tearing_down);
2970
2971 do {
2972 ret = wait_event_timeout(se_sess->cmd_list_wq,
2973 percpu_ref_is_zero(&se_sess->cmd_count),
2974 180 * HZ);
2975 list_for_each_entry(cmd, &se_sess->sess_cmd_list, se_cmd_list)
2976 target_show_cmd("session shutdown: still waiting for ",
2977 cmd);
2978 } while (ret <= 0);
2979 }
2980 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2981
2982 /*
2983 * Prevent that new percpu_ref_tryget_live() calls succeed and wait until
2984 * all references to the LUN have been released. Called during LUN shutdown.
2985 */
2986 void transport_clear_lun_ref(struct se_lun *lun)
2987 {
2988 percpu_ref_kill(&lun->lun_ref);
2989 wait_for_completion(&lun->lun_shutdown_comp);
2990 }
2991
2992 static bool
2993 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2994 bool *aborted, bool *tas, unsigned long *flags)
2995 __releases(&cmd->t_state_lock)
2996 __acquires(&cmd->t_state_lock)
2997 {
2998
2999 assert_spin_locked(&cmd->t_state_lock);
3000 WARN_ON_ONCE(!irqs_disabled());
3001
3002 if (fabric_stop)
3003 cmd->transport_state |= CMD_T_FABRIC_STOP;
3004
3005 if (cmd->transport_state & CMD_T_ABORTED)
3006 *aborted = true;
3007
3008 if (cmd->transport_state & CMD_T_TAS)
3009 *tas = true;
3010
3011 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
3012 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3013 return false;
3014
3015 if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
3016 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3017 return false;
3018
3019 if (!(cmd->transport_state & CMD_T_ACTIVE))
3020 return false;
3021
3022 if (fabric_stop && *aborted)
3023 return false;
3024
3025 cmd->transport_state |= CMD_T_STOP;
3026
3027 target_show_cmd("wait_for_tasks: Stopping ", cmd);
3028
3029 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
3030
3031 while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
3032 180 * HZ))
3033 target_show_cmd("wait for tasks: ", cmd);
3034
3035 spin_lock_irqsave(&cmd->t_state_lock, *flags);
3036 cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
3037
3038 pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
3039 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
3040
3041 return true;
3042 }
3043
3044 /**
3045 * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
3046 * @cmd: command to wait on
3047 */
3048 bool transport_wait_for_tasks(struct se_cmd *cmd)
3049 {
3050 unsigned long flags;
3051 bool ret, aborted = false, tas = false;
3052
3053 spin_lock_irqsave(&cmd->t_state_lock, flags);
3054 ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
3055 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3056
3057 return ret;
3058 }
3059 EXPORT_SYMBOL(transport_wait_for_tasks);
3060
3061 struct sense_info {
3062 u8 key;
3063 u8 asc;
3064 u8 ascq;
3065 bool add_sector_info;
3066 };
3067
3068 static const struct sense_info sense_info_table[] = {
3069 [TCM_NO_SENSE] = {
3070 .key = NOT_READY
3071 },
3072 [TCM_NON_EXISTENT_LUN] = {
3073 .key = ILLEGAL_REQUEST,
3074 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
3075 },
3076 [TCM_UNSUPPORTED_SCSI_OPCODE] = {
3077 .key = ILLEGAL_REQUEST,
3078 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3079 },
3080 [TCM_SECTOR_COUNT_TOO_MANY] = {
3081 .key = ILLEGAL_REQUEST,
3082 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3083 },
3084 [TCM_UNKNOWN_MODE_PAGE] = {
3085 .key = ILLEGAL_REQUEST,
3086 .asc = 0x24, /* INVALID FIELD IN CDB */
3087 },
3088 [TCM_CHECK_CONDITION_ABORT_CMD] = {
3089 .key = ABORTED_COMMAND,
3090 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3091 .ascq = 0x03,
3092 },
3093 [TCM_INCORRECT_AMOUNT_OF_DATA] = {
3094 .key = ABORTED_COMMAND,
3095 .asc = 0x0c, /* WRITE ERROR */
3096 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3097 },
3098 [TCM_INVALID_CDB_FIELD] = {
3099 .key = ILLEGAL_REQUEST,
3100 .asc = 0x24, /* INVALID FIELD IN CDB */
3101 },
3102 [TCM_INVALID_PARAMETER_LIST] = {
3103 .key = ILLEGAL_REQUEST,
3104 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3105 },
3106 [TCM_TOO_MANY_TARGET_DESCS] = {
3107 .key = ILLEGAL_REQUEST,
3108 .asc = 0x26,
3109 .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3110 },
3111 [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3112 .key = ILLEGAL_REQUEST,
3113 .asc = 0x26,
3114 .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3115 },
3116 [TCM_TOO_MANY_SEGMENT_DESCS] = {
3117 .key = ILLEGAL_REQUEST,
3118 .asc = 0x26,
3119 .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3120 },
3121 [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3122 .key = ILLEGAL_REQUEST,
3123 .asc = 0x26,
3124 .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3125 },
3126 [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3127 .key = ILLEGAL_REQUEST,
3128 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3129 },
3130 [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3131 .key = ILLEGAL_REQUEST,
3132 .asc = 0x0c, /* WRITE ERROR */
3133 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3134 },
3135 [TCM_SERVICE_CRC_ERROR] = {
3136 .key = ABORTED_COMMAND,
3137 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3138 .ascq = 0x05, /* N/A */
3139 },
3140 [TCM_SNACK_REJECTED] = {
3141 .key = ABORTED_COMMAND,
3142 .asc = 0x11, /* READ ERROR */
3143 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3144 },
3145 [TCM_WRITE_PROTECTED] = {
3146 .key = DATA_PROTECT,
3147 .asc = 0x27, /* WRITE PROTECTED */
3148 },
3149 [TCM_ADDRESS_OUT_OF_RANGE] = {
3150 .key = ILLEGAL_REQUEST,
3151 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3152 },
3153 [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3154 .key = UNIT_ATTENTION,
3155 },
3156 [TCM_CHECK_CONDITION_NOT_READY] = {
3157 .key = NOT_READY,
3158 },
3159 [TCM_MISCOMPARE_VERIFY] = {
3160 .key = MISCOMPARE,
3161 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3162 .ascq = 0x00,
3163 },
3164 [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
3165 .key = ABORTED_COMMAND,
3166 .asc = 0x10,
3167 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
3168 .add_sector_info = true,
3169 },
3170 [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
3171 .key = ABORTED_COMMAND,
3172 .asc = 0x10,
3173 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
3174 .add_sector_info = true,
3175 },
3176 [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
3177 .key = ABORTED_COMMAND,
3178 .asc = 0x10,
3179 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
3180 .add_sector_info = true,
3181 },
3182 [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
3183 .key = COPY_ABORTED,
3184 .asc = 0x0d,
3185 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
3186
3187 },
3188 [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
3189 /*
3190 * Returning ILLEGAL REQUEST would cause immediate IO errors on
3191 * Solaris initiators. Returning NOT READY instead means the
3192 * operations will be retried a finite number of times and we
3193 * can survive intermittent errors.
3194 */
3195 .key = NOT_READY,
3196 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
3197 },
3198 [TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
3199 /*
3200 * From spc4r22 section5.7.7,5.7.8
3201 * If a PERSISTENT RESERVE OUT command with a REGISTER service action
3202 * or a REGISTER AND IGNORE EXISTING KEY service action or
3203 * REGISTER AND MOVE service actionis attempted,
3204 * but there are insufficient device server resources to complete the
3205 * operation, then the command shall be terminated with CHECK CONDITION
3206 * status, with the sense key set to ILLEGAL REQUEST,and the additonal
3207 * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
3208 */
3209 .key = ILLEGAL_REQUEST,
3210 .asc = 0x55,
3211 .ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
3212 },
3213 };
3214
3215 /**
3216 * translate_sense_reason - translate a sense reason into T10 key, asc and ascq
3217 * @cmd: SCSI command in which the resulting sense buffer or SCSI status will
3218 * be stored.
3219 * @reason: LIO sense reason code. If this argument has the value
3220 * TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If
3221 * dequeuing a unit attention fails due to multiple commands being processed
3222 * concurrently, set the command status to BUSY.
3223 *
3224 * Return: 0 upon success or -EINVAL if the sense buffer is too small.
3225 */
3226 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
3227 {
3228 const struct sense_info *si;
3229 u8 *buffer = cmd->sense_buffer;
3230 int r = (__force int)reason;
3231 u8 key, asc, ascq;
3232 bool desc_format = target_sense_desc_format(cmd->se_dev);
3233
3234 if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
3235 si = &sense_info_table[r];
3236 else
3237 si = &sense_info_table[(__force int)
3238 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3239
3240 key = si->key;
3241 if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
3242 if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc,
3243 &ascq)) {
3244 cmd->scsi_status = SAM_STAT_BUSY;
3245 return;
3246 }
3247 } else if (si->asc == 0) {
3248 WARN_ON_ONCE(cmd->scsi_asc == 0);
3249 asc = cmd->scsi_asc;
3250 ascq = cmd->scsi_ascq;
3251 } else {
3252 asc = si->asc;
3253 ascq = si->ascq;
3254 }
3255
3256 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
3257 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
3258 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
3259 scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
3260 if (si->add_sector_info)
3261 WARN_ON_ONCE(scsi_set_sense_information(buffer,
3262 cmd->scsi_sense_length,
3263 cmd->bad_sector) < 0);
3264 }
3265
3266 int
3267 transport_send_check_condition_and_sense(struct se_cmd *cmd,
3268 sense_reason_t reason, int from_transport)
3269 {
3270 unsigned long flags;
3271
3272 WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3273
3274 spin_lock_irqsave(&cmd->t_state_lock, flags);
3275 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
3276 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3277 return 0;
3278 }
3279 cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
3280 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3281
3282 if (!from_transport)
3283 translate_sense_reason(cmd, reason);
3284
3285 trace_target_cmd_complete(cmd);
3286 return cmd->se_tfo->queue_status(cmd);
3287 }
3288 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
3289
3290 /**
3291 * target_send_busy - Send SCSI BUSY status back to the initiator
3292 * @cmd: SCSI command for which to send a BUSY reply.
3293 *
3294 * Note: Only call this function if target_submit_cmd*() failed.
3295 */
3296 int target_send_busy(struct se_cmd *cmd)
3297 {
3298 WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3299
3300 cmd->scsi_status = SAM_STAT_BUSY;
3301 trace_target_cmd_complete(cmd);
3302 return cmd->se_tfo->queue_status(cmd);
3303 }
3304 EXPORT_SYMBOL(target_send_busy);
3305
3306 static void target_tmr_work(struct work_struct *work)
3307 {
3308 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3309 struct se_device *dev = cmd->se_dev;
3310 struct se_tmr_req *tmr = cmd->se_tmr_req;
3311 int ret;
3312
3313 if (cmd->transport_state & CMD_T_ABORTED)
3314 goto aborted;
3315
3316 switch (tmr->function) {
3317 case TMR_ABORT_TASK:
3318 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3319 break;
3320 case TMR_ABORT_TASK_SET:
3321 case TMR_CLEAR_ACA:
3322 case TMR_CLEAR_TASK_SET:
3323 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3324 break;
3325 case TMR_LUN_RESET:
3326 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3327 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3328 TMR_FUNCTION_REJECTED;
3329 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3330 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3331 cmd->orig_fe_lun, 0x29,
3332 ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3333 }
3334 break;
3335 case TMR_TARGET_WARM_RESET:
3336 tmr->response = TMR_FUNCTION_REJECTED;
3337 break;
3338 case TMR_TARGET_COLD_RESET:
3339 tmr->response = TMR_FUNCTION_REJECTED;
3340 break;
3341 default:
3342 pr_err("Unknown TMR function: 0x%02x.\n",
3343 tmr->function);
3344 tmr->response = TMR_FUNCTION_REJECTED;
3345 break;
3346 }
3347
3348 if (cmd->transport_state & CMD_T_ABORTED)
3349 goto aborted;
3350
3351 cmd->se_tfo->queue_tm_rsp(cmd);
3352
3353 transport_lun_remove_cmd(cmd);
3354 transport_cmd_check_stop_to_fabric(cmd);
3355 return;
3356
3357 aborted:
3358 target_handle_abort(cmd);
3359 }
3360
3361 int transport_generic_handle_tmr(
3362 struct se_cmd *cmd)
3363 {
3364 unsigned long flags;
3365 bool aborted = false;
3366
3367 spin_lock_irqsave(&cmd->t_state_lock, flags);
3368 if (cmd->transport_state & CMD_T_ABORTED) {
3369 aborted = true;
3370 } else {
3371 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3372 cmd->transport_state |= CMD_T_ACTIVE;
3373 }
3374 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3375
3376 if (aborted) {
3377 pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d ref_tag: %llu tag: %llu\n",
3378 cmd->se_tmr_req->function,
3379 cmd->se_tmr_req->ref_task_tag, cmd->tag);
3380 target_handle_abort(cmd);
3381 return 0;
3382 }
3383
3384 INIT_WORK(&cmd->work, target_tmr_work);
3385 schedule_work(&cmd->work);
3386 return 0;
3387 }
3388 EXPORT_SYMBOL(transport_generic_handle_tmr);
3389
3390 bool
3391 target_check_wce(struct se_device *dev)
3392 {
3393 bool wce = false;
3394
3395 if (dev->transport->get_write_cache)
3396 wce = dev->transport->get_write_cache(dev);
3397 else if (dev->dev_attrib.emulate_write_cache > 0)
3398 wce = true;
3399
3400 return wce;
3401 }
3402
3403 bool
3404 target_check_fua(struct se_device *dev)
3405 {
3406 return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3407 }
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