?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge tag 'block-5.11-2021-01-10' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / drivers / target / target_core_transport.c
blobfca4bd079d02cdb9e41fcb468f5f5b621f0c5089
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_count_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 spin_lock_init(&se_sess->sess_cmd_lock);
232 init_waitqueue_head(&se_sess->cmd_count_wq);
233 init_completion(&se_sess->stop_done);
234 atomic_set(&se_sess->stopped, 0);
235 return percpu_ref_init(&se_sess->cmd_count,
236 target_release_sess_cmd_refcnt, 0, GFP_KERNEL);
237 }
238 EXPORT_SYMBOL(transport_init_session);
239
240 void transport_uninit_session(struct se_session *se_sess)
241 {
242 /*
243 * Drivers like iscsi and loop do not call target_stop_session
244 * during session shutdown so we have to drop the ref taken at init
245 * time here.
246 */
247 if (!atomic_read(&se_sess->stopped))
248 percpu_ref_put(&se_sess->cmd_count);
249
250 percpu_ref_exit(&se_sess->cmd_count);
251 }
252
253 /**
254 * transport_alloc_session - allocate a session object and initialize it
255 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
256 */
257 struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
258 {
259 struct se_session *se_sess;
260 int ret;
261
262 se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
263 if (!se_sess) {
264 pr_err("Unable to allocate struct se_session from"
265 " se_sess_cache\n");
266 return ERR_PTR(-ENOMEM);
267 }
268 ret = transport_init_session(se_sess);
269 if (ret < 0) {
270 kmem_cache_free(se_sess_cache, se_sess);
271 return ERR_PTR(ret);
272 }
273 se_sess->sup_prot_ops = sup_prot_ops;
274
275 return se_sess;
276 }
277 EXPORT_SYMBOL(transport_alloc_session);
278
279 /**
280 * transport_alloc_session_tags - allocate target driver private data
281 * @se_sess: Session pointer.
282 * @tag_num: Maximum number of in-flight commands between initiator and target.
283 * @tag_size: Size in bytes of the private data a target driver associates with
284 * each command.
285 */
286 int transport_alloc_session_tags(struct se_session *se_sess,
287 unsigned int tag_num, unsigned int tag_size)
288 {
289 int rc;
290
291 se_sess->sess_cmd_map = kvcalloc(tag_size, tag_num,
292 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
293 if (!se_sess->sess_cmd_map) {
294 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
295 return -ENOMEM;
296 }
297
298 rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
299 false, GFP_KERNEL, NUMA_NO_NODE);
300 if (rc < 0) {
301 pr_err("Unable to init se_sess->sess_tag_pool,"
302 " tag_num: %u\n", tag_num);
303 kvfree(se_sess->sess_cmd_map);
304 se_sess->sess_cmd_map = NULL;
305 return -ENOMEM;
306 }
307
308 return 0;
309 }
310 EXPORT_SYMBOL(transport_alloc_session_tags);
311
312 /**
313 * transport_init_session_tags - allocate a session and target driver private data
314 * @tag_num: Maximum number of in-flight commands between initiator and target.
315 * @tag_size: Size in bytes of the private data a target driver associates with
316 * each command.
317 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
318 */
319 static struct se_session *
320 transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
321 enum target_prot_op sup_prot_ops)
322 {
323 struct se_session *se_sess;
324 int rc;
325
326 if (tag_num != 0 && !tag_size) {
327 pr_err("init_session_tags called with percpu-ida tag_num:"
328 " %u, but zero tag_size\n", tag_num);
329 return ERR_PTR(-EINVAL);
330 }
331 if (!tag_num && tag_size) {
332 pr_err("init_session_tags called with percpu-ida tag_size:"
333 " %u, but zero tag_num\n", tag_size);
334 return ERR_PTR(-EINVAL);
335 }
336
337 se_sess = transport_alloc_session(sup_prot_ops);
338 if (IS_ERR(se_sess))
339 return se_sess;
340
341 rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
342 if (rc < 0) {
343 transport_free_session(se_sess);
344 return ERR_PTR(-ENOMEM);
345 }
346
347 return se_sess;
348 }
349
350 /*
351 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
352 */
353 void __transport_register_session(
354 struct se_portal_group *se_tpg,
355 struct se_node_acl *se_nacl,
356 struct se_session *se_sess,
357 void *fabric_sess_ptr)
358 {
359 const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
360 unsigned char buf[PR_REG_ISID_LEN];
361 unsigned long flags;
362
363 se_sess->se_tpg = se_tpg;
364 se_sess->fabric_sess_ptr = fabric_sess_ptr;
365 /*
366 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
367 *
368 * Only set for struct se_session's that will actually be moving I/O.
369 * eg: *NOT* discovery sessions.
370 */
371 if (se_nacl) {
372 /*
373 *
374 * Determine if fabric allows for T10-PI feature bits exposed to
375 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
376 *
377 * If so, then always save prot_type on a per se_node_acl node
378 * basis and re-instate the previous sess_prot_type to avoid
379 * disabling PI from below any previously initiator side
380 * registered LUNs.
381 */
382 if (se_nacl->saved_prot_type)
383 se_sess->sess_prot_type = se_nacl->saved_prot_type;
384 else if (tfo->tpg_check_prot_fabric_only)
385 se_sess->sess_prot_type = se_nacl->saved_prot_type =
386 tfo->tpg_check_prot_fabric_only(se_tpg);
387 /*
388 * If the fabric module supports an ISID based TransportID,
389 * save this value in binary from the fabric I_T Nexus now.
390 */
391 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
392 memset(&buf[0], 0, PR_REG_ISID_LEN);
393 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
394 &buf[0], PR_REG_ISID_LEN);
395 se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
396 }
397
398 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
399 /*
400 * The se_nacl->nacl_sess pointer will be set to the
401 * last active I_T Nexus for each struct se_node_acl.
402 */
403 se_nacl->nacl_sess = se_sess;
404
405 list_add_tail(&se_sess->sess_acl_list,
406 &se_nacl->acl_sess_list);
407 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
408 }
409 list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
410
411 pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
412 se_tpg->se_tpg_tfo->fabric_name, se_sess->fabric_sess_ptr);
413 }
414 EXPORT_SYMBOL(__transport_register_session);
415
416 void transport_register_session(
417 struct se_portal_group *se_tpg,
418 struct se_node_acl *se_nacl,
419 struct se_session *se_sess,
420 void *fabric_sess_ptr)
421 {
422 unsigned long flags;
423
424 spin_lock_irqsave(&se_tpg->session_lock, flags);
425 __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
426 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
427 }
428 EXPORT_SYMBOL(transport_register_session);
429
430 struct se_session *
431 target_setup_session(struct se_portal_group *tpg,
432 unsigned int tag_num, unsigned int tag_size,
433 enum target_prot_op prot_op,
434 const char *initiatorname, void *private,
435 int (*callback)(struct se_portal_group *,
436 struct se_session *, void *))
437 {
438 struct se_session *sess;
439
440 /*
441 * If the fabric driver is using percpu-ida based pre allocation
442 * of I/O descriptor tags, go ahead and perform that setup now..
443 */
444 if (tag_num != 0)
445 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
446 else
447 sess = transport_alloc_session(prot_op);
448
449 if (IS_ERR(sess))
450 return sess;
451
452 sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
453 (unsigned char *)initiatorname);
454 if (!sess->se_node_acl) {
455 transport_free_session(sess);
456 return ERR_PTR(-EACCES);
457 }
458 /*
459 * Go ahead and perform any remaining fabric setup that is
460 * required before transport_register_session().
461 */
462 if (callback != NULL) {
463 int rc = callback(tpg, sess, private);
464 if (rc) {
465 transport_free_session(sess);
466 return ERR_PTR(rc);
467 }
468 }
469
470 transport_register_session(tpg, sess->se_node_acl, sess, private);
471 return sess;
472 }
473 EXPORT_SYMBOL(target_setup_session);
474
475 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
476 {
477 struct se_session *se_sess;
478 ssize_t len = 0;
479
480 spin_lock_bh(&se_tpg->session_lock);
481 list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
482 if (!se_sess->se_node_acl)
483 continue;
484 if (!se_sess->se_node_acl->dynamic_node_acl)
485 continue;
486 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
487 break;
488
489 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
490 se_sess->se_node_acl->initiatorname);
491 len += 1; /* Include NULL terminator */
492 }
493 spin_unlock_bh(&se_tpg->session_lock);
494
495 return len;
496 }
497 EXPORT_SYMBOL(target_show_dynamic_sessions);
498
499 static void target_complete_nacl(struct kref *kref)
500 {
501 struct se_node_acl *nacl = container_of(kref,
502 struct se_node_acl, acl_kref);
503 struct se_portal_group *se_tpg = nacl->se_tpg;
504
505 if (!nacl->dynamic_stop) {
506 complete(&nacl->acl_free_comp);
507 return;
508 }
509
510 mutex_lock(&se_tpg->acl_node_mutex);
511 list_del_init(&nacl->acl_list);
512 mutex_unlock(&se_tpg->acl_node_mutex);
513
514 core_tpg_wait_for_nacl_pr_ref(nacl);
515 core_free_device_list_for_node(nacl, se_tpg);
516 kfree(nacl);
517 }
518
519 void target_put_nacl(struct se_node_acl *nacl)
520 {
521 kref_put(&nacl->acl_kref, target_complete_nacl);
522 }
523 EXPORT_SYMBOL(target_put_nacl);
524
525 void transport_deregister_session_configfs(struct se_session *se_sess)
526 {
527 struct se_node_acl *se_nacl;
528 unsigned long flags;
529 /*
530 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
531 */
532 se_nacl = se_sess->se_node_acl;
533 if (se_nacl) {
534 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
535 if (!list_empty(&se_sess->sess_acl_list))
536 list_del_init(&se_sess->sess_acl_list);
537 /*
538 * If the session list is empty, then clear the pointer.
539 * Otherwise, set the struct se_session pointer from the tail
540 * element of the per struct se_node_acl active session list.
541 */
542 if (list_empty(&se_nacl->acl_sess_list))
543 se_nacl->nacl_sess = NULL;
544 else {
545 se_nacl->nacl_sess = container_of(
546 se_nacl->acl_sess_list.prev,
547 struct se_session, sess_acl_list);
548 }
549 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
550 }
551 }
552 EXPORT_SYMBOL(transport_deregister_session_configfs);
553
554 void transport_free_session(struct se_session *se_sess)
555 {
556 struct se_node_acl *se_nacl = se_sess->se_node_acl;
557
558 /*
559 * Drop the se_node_acl->nacl_kref obtained from within
560 * core_tpg_get_initiator_node_acl().
561 */
562 if (se_nacl) {
563 struct se_portal_group *se_tpg = se_nacl->se_tpg;
564 const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
565 unsigned long flags;
566
567 se_sess->se_node_acl = NULL;
568
569 /*
570 * Also determine if we need to drop the extra ->cmd_kref if
571 * it had been previously dynamically generated, and
572 * the endpoint is not caching dynamic ACLs.
573 */
574 mutex_lock(&se_tpg->acl_node_mutex);
575 if (se_nacl->dynamic_node_acl &&
576 !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
577 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
578 if (list_empty(&se_nacl->acl_sess_list))
579 se_nacl->dynamic_stop = true;
580 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
581
582 if (se_nacl->dynamic_stop)
583 list_del_init(&se_nacl->acl_list);
584 }
585 mutex_unlock(&se_tpg->acl_node_mutex);
586
587 if (se_nacl->dynamic_stop)
588 target_put_nacl(se_nacl);
589
590 target_put_nacl(se_nacl);
591 }
592 if (se_sess->sess_cmd_map) {
593 sbitmap_queue_free(&se_sess->sess_tag_pool);
594 kvfree(se_sess->sess_cmd_map);
595 }
596 transport_uninit_session(se_sess);
597 kmem_cache_free(se_sess_cache, se_sess);
598 }
599 EXPORT_SYMBOL(transport_free_session);
600
601 static int target_release_res(struct se_device *dev, void *data)
602 {
603 struct se_session *sess = data;
604
605 if (dev->reservation_holder == sess)
606 target_release_reservation(dev);
607 return 0;
608 }
609
610 void transport_deregister_session(struct se_session *se_sess)
611 {
612 struct se_portal_group *se_tpg = se_sess->se_tpg;
613 unsigned long flags;
614
615 if (!se_tpg) {
616 transport_free_session(se_sess);
617 return;
618 }
619
620 spin_lock_irqsave(&se_tpg->session_lock, flags);
621 list_del(&se_sess->sess_list);
622 se_sess->se_tpg = NULL;
623 se_sess->fabric_sess_ptr = NULL;
624 spin_unlock_irqrestore(&se_tpg->session_lock, flags);
625
626 /*
627 * Since the session is being removed, release SPC-2
628 * reservations held by the session that is disappearing.
629 */
630 target_for_each_device(target_release_res, se_sess);
631
632 pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
633 se_tpg->se_tpg_tfo->fabric_name);
634 /*
635 * If last kref is dropping now for an explicit NodeACL, awake sleeping
636 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
637 * removal context from within transport_free_session() code.
638 *
639 * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
640 * to release all remaining generate_node_acl=1 created ACL resources.
641 */
642
643 transport_free_session(se_sess);
644 }
645 EXPORT_SYMBOL(transport_deregister_session);
646
647 void target_remove_session(struct se_session *se_sess)
648 {
649 transport_deregister_session_configfs(se_sess);
650 transport_deregister_session(se_sess);
651 }
652 EXPORT_SYMBOL(target_remove_session);
653
654 static void target_remove_from_state_list(struct se_cmd *cmd)
655 {
656 struct se_device *dev = cmd->se_dev;
657 unsigned long flags;
658
659 if (!dev)
660 return;
661
662 spin_lock_irqsave(&dev->queues[cmd->cpuid].lock, flags);
663 if (cmd->state_active) {
664 list_del(&cmd->state_list);
665 cmd->state_active = false;
666 }
667 spin_unlock_irqrestore(&dev->queues[cmd->cpuid].lock, flags);
668 }
669
670 /*
671 * This function is called by the target core after the target core has
672 * finished processing a SCSI command or SCSI TMF. Both the regular command
673 * processing code and the code for aborting commands can call this
674 * function. CMD_T_STOP is set if and only if another thread is waiting
675 * inside transport_wait_for_tasks() for t_transport_stop_comp.
676 */
677 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
678 {
679 unsigned long flags;
680
681 target_remove_from_state_list(cmd);
682
683 /*
684 * Clear struct se_cmd->se_lun before the handoff to FE.
685 */
686 cmd->se_lun = NULL;
687
688 spin_lock_irqsave(&cmd->t_state_lock, flags);
689 /*
690 * Determine if frontend context caller is requesting the stopping of
691 * this command for frontend exceptions.
692 */
693 if (cmd->transport_state & CMD_T_STOP) {
694 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
695 __func__, __LINE__, cmd->tag);
696
697 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
698
699 complete_all(&cmd->t_transport_stop_comp);
700 return 1;
701 }
702 cmd->transport_state &= ~CMD_T_ACTIVE;
703 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
704
705 /*
706 * Some fabric modules like tcm_loop can release their internally
707 * allocated I/O reference and struct se_cmd now.
708 *
709 * Fabric modules are expected to return '1' here if the se_cmd being
710 * passed is released at this point, or zero if not being released.
711 */
712 return cmd->se_tfo->check_stop_free(cmd);
713 }
714
715 static void transport_lun_remove_cmd(struct se_cmd *cmd)
716 {
717 struct se_lun *lun = cmd->se_lun;
718
719 if (!lun)
720 return;
721
722 if (cmpxchg(&cmd->lun_ref_active, true, false))
723 percpu_ref_put(&lun->lun_ref);
724 }
725
726 static void target_complete_failure_work(struct work_struct *work)
727 {
728 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
729
730 transport_generic_request_failure(cmd,
731 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
732 }
733
734 /*
735 * Used when asking transport to copy Sense Data from the underlying
736 * Linux/SCSI struct scsi_cmnd
737 */
738 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
739 {
740 struct se_device *dev = cmd->se_dev;
741
742 WARN_ON(!cmd->se_lun);
743
744 if (!dev)
745 return NULL;
746
747 if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
748 return NULL;
749
750 cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
751
752 pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
753 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
754 return cmd->sense_buffer;
755 }
756
757 void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
758 {
759 unsigned char *cmd_sense_buf;
760 unsigned long flags;
761
762 spin_lock_irqsave(&cmd->t_state_lock, flags);
763 cmd_sense_buf = transport_get_sense_buffer(cmd);
764 if (!cmd_sense_buf) {
765 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
766 return;
767 }
768
769 cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
770 memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
771 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
772 }
773 EXPORT_SYMBOL(transport_copy_sense_to_cmd);
774
775 static void target_handle_abort(struct se_cmd *cmd)
776 {
777 bool tas = cmd->transport_state & CMD_T_TAS;
778 bool ack_kref = cmd->se_cmd_flags & SCF_ACK_KREF;
779 int ret;
780
781 pr_debug("tag %#llx: send_abort_response = %d\n", cmd->tag, tas);
782
783 if (tas) {
784 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
785 cmd->scsi_status = SAM_STAT_TASK_ABORTED;
786 pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
787 cmd->t_task_cdb[0], cmd->tag);
788 trace_target_cmd_complete(cmd);
789 ret = cmd->se_tfo->queue_status(cmd);
790 if (ret) {
791 transport_handle_queue_full(cmd, cmd->se_dev,
792 ret, false);
793 return;
794 }
795 } else {
796 cmd->se_tmr_req->response = TMR_FUNCTION_REJECTED;
797 cmd->se_tfo->queue_tm_rsp(cmd);
798 }
799 } else {
800 /*
801 * Allow the fabric driver to unmap any resources before
802 * releasing the descriptor via TFO->release_cmd().
803 */
804 cmd->se_tfo->aborted_task(cmd);
805 if (ack_kref)
806 WARN_ON_ONCE(target_put_sess_cmd(cmd) != 0);
807 /*
808 * To do: establish a unit attention condition on the I_T
809 * nexus associated with cmd. See also the paragraph "Aborting
810 * commands" in SAM.
811 */
812 }
813
814 WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0);
815
816 transport_lun_remove_cmd(cmd);
817
818 transport_cmd_check_stop_to_fabric(cmd);
819 }
820
821 static void target_abort_work(struct work_struct *work)
822 {
823 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
824
825 target_handle_abort(cmd);
826 }
827
828 static bool target_cmd_interrupted(struct se_cmd *cmd)
829 {
830 int post_ret;
831
832 if (cmd->transport_state & CMD_T_ABORTED) {
833 if (cmd->transport_complete_callback)
834 cmd->transport_complete_callback(cmd, false, &post_ret);
835 INIT_WORK(&cmd->work, target_abort_work);
836 queue_work(target_completion_wq, &cmd->work);
837 return true;
838 } else if (cmd->transport_state & CMD_T_STOP) {
839 if (cmd->transport_complete_callback)
840 cmd->transport_complete_callback(cmd, false, &post_ret);
841 complete_all(&cmd->t_transport_stop_comp);
842 return true;
843 }
844
845 return false;
846 }
847
848 /* May be called from interrupt context so must not sleep. */
849 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
850 {
851 int success;
852 unsigned long flags;
853
854 if (target_cmd_interrupted(cmd))
855 return;
856
857 cmd->scsi_status = scsi_status;
858
859 spin_lock_irqsave(&cmd->t_state_lock, flags);
860 switch (cmd->scsi_status) {
861 case SAM_STAT_CHECK_CONDITION:
862 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
863 success = 1;
864 else
865 success = 0;
866 break;
867 default:
868 success = 1;
869 break;
870 }
871
872 cmd->t_state = TRANSPORT_COMPLETE;
873 cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
874 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
875
876 INIT_WORK(&cmd->work, success ? target_complete_ok_work :
877 target_complete_failure_work);
878 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
879 }
880 EXPORT_SYMBOL(target_complete_cmd);
881
882 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
883 {
884 if ((scsi_status == SAM_STAT_GOOD ||
885 cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
886 length < cmd->data_length) {
887 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
888 cmd->residual_count += cmd->data_length - length;
889 } else {
890 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
891 cmd->residual_count = cmd->data_length - length;
892 }
893
894 cmd->data_length = length;
895 }
896
897 target_complete_cmd(cmd, scsi_status);
898 }
899 EXPORT_SYMBOL(target_complete_cmd_with_length);
900
901 static void target_add_to_state_list(struct se_cmd *cmd)
902 {
903 struct se_device *dev = cmd->se_dev;
904 unsigned long flags;
905
906 spin_lock_irqsave(&dev->queues[cmd->cpuid].lock, flags);
907 if (!cmd->state_active) {
908 list_add_tail(&cmd->state_list,
909 &dev->queues[cmd->cpuid].state_list);
910 cmd->state_active = true;
911 }
912 spin_unlock_irqrestore(&dev->queues[cmd->cpuid].lock, flags);
913 }
914
915 /*
916 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
917 */
918 static void transport_write_pending_qf(struct se_cmd *cmd);
919 static void transport_complete_qf(struct se_cmd *cmd);
920
921 void target_qf_do_work(struct work_struct *work)
922 {
923 struct se_device *dev = container_of(work, struct se_device,
924 qf_work_queue);
925 LIST_HEAD(qf_cmd_list);
926 struct se_cmd *cmd, *cmd_tmp;
927
928 spin_lock_irq(&dev->qf_cmd_lock);
929 list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
930 spin_unlock_irq(&dev->qf_cmd_lock);
931
932 list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
933 list_del(&cmd->se_qf_node);
934 atomic_dec_mb(&dev->dev_qf_count);
935
936 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
937 " context: %s\n", cmd->se_tfo->fabric_name, cmd,
938 (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
939 (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
940 : "UNKNOWN");
941
942 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
943 transport_write_pending_qf(cmd);
944 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
945 cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
946 transport_complete_qf(cmd);
947 }
948 }
949
950 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
951 {
952 switch (cmd->data_direction) {
953 case DMA_NONE:
954 return "NONE";
955 case DMA_FROM_DEVICE:
956 return "READ";
957 case DMA_TO_DEVICE:
958 return "WRITE";
959 case DMA_BIDIRECTIONAL:
960 return "BIDI";
961 default:
962 break;
963 }
964
965 return "UNKNOWN";
966 }
967
968 void transport_dump_dev_state(
969 struct se_device *dev,
970 char *b,
971 int *bl)
972 {
973 *bl += sprintf(b + *bl, "Status: ");
974 if (dev->export_count)
975 *bl += sprintf(b + *bl, "ACTIVATED");
976 else
977 *bl += sprintf(b + *bl, "DEACTIVATED");
978
979 *bl += sprintf(b + *bl, " Max Queue Depth: %d", dev->queue_depth);
980 *bl += sprintf(b + *bl, " SectorSize: %u HwMaxSectors: %u\n",
981 dev->dev_attrib.block_size,
982 dev->dev_attrib.hw_max_sectors);
983 *bl += sprintf(b + *bl, " ");
984 }
985
986 void transport_dump_vpd_proto_id(
987 struct t10_vpd *vpd,
988 unsigned char *p_buf,
989 int p_buf_len)
990 {
991 unsigned char buf[VPD_TMP_BUF_SIZE];
992 int len;
993
994 memset(buf, 0, VPD_TMP_BUF_SIZE);
995 len = sprintf(buf, "T10 VPD Protocol Identifier: ");
996
997 switch (vpd->protocol_identifier) {
998 case 0x00:
999 sprintf(buf+len, "Fibre Channel\n");
1000 break;
1001 case 0x10:
1002 sprintf(buf+len, "Parallel SCSI\n");
1003 break;
1004 case 0x20:
1005 sprintf(buf+len, "SSA\n");
1006 break;
1007 case 0x30:
1008 sprintf(buf+len, "IEEE 1394\n");
1009 break;
1010 case 0x40:
1011 sprintf(buf+len, "SCSI Remote Direct Memory Access"
1012 " Protocol\n");
1013 break;
1014 case 0x50:
1015 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
1016 break;
1017 case 0x60:
1018 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
1019 break;
1020 case 0x70:
1021 sprintf(buf+len, "Automation/Drive Interface Transport"
1022 " Protocol\n");
1023 break;
1024 case 0x80:
1025 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
1026 break;
1027 default:
1028 sprintf(buf+len, "Unknown 0x%02x\n",
1029 vpd->protocol_identifier);
1030 break;
1031 }
1032
1033 if (p_buf)
1034 strncpy(p_buf, buf, p_buf_len);
1035 else
1036 pr_debug("%s", buf);
1037 }
1038
1039 void
1040 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1041 {
1042 /*
1043 * Check if the Protocol Identifier Valid (PIV) bit is set..
1044 *
1045 * from spc3r23.pdf section 7.5.1
1046 */
1047 if (page_83[1] & 0x80) {
1048 vpd->protocol_identifier = (page_83[0] & 0xf0);
1049 vpd->protocol_identifier_set = 1;
1050 transport_dump_vpd_proto_id(vpd, NULL, 0);
1051 }
1052 }
1053 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1054
1055 int transport_dump_vpd_assoc(
1056 struct t10_vpd *vpd,
1057 unsigned char *p_buf,
1058 int p_buf_len)
1059 {
1060 unsigned char buf[VPD_TMP_BUF_SIZE];
1061 int ret = 0;
1062 int len;
1063
1064 memset(buf, 0, VPD_TMP_BUF_SIZE);
1065 len = sprintf(buf, "T10 VPD Identifier Association: ");
1066
1067 switch (vpd->association) {
1068 case 0x00:
1069 sprintf(buf+len, "addressed logical unit\n");
1070 break;
1071 case 0x10:
1072 sprintf(buf+len, "target port\n");
1073 break;
1074 case 0x20:
1075 sprintf(buf+len, "SCSI target device\n");
1076 break;
1077 default:
1078 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1079 ret = -EINVAL;
1080 break;
1081 }
1082
1083 if (p_buf)
1084 strncpy(p_buf, buf, p_buf_len);
1085 else
1086 pr_debug("%s", buf);
1087
1088 return ret;
1089 }
1090
1091 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1092 {
1093 /*
1094 * The VPD identification association..
1095 *
1096 * from spc3r23.pdf Section 7.6.3.1 Table 297
1097 */
1098 vpd->association = (page_83[1] & 0x30);
1099 return transport_dump_vpd_assoc(vpd, NULL, 0);
1100 }
1101 EXPORT_SYMBOL(transport_set_vpd_assoc);
1102
1103 int transport_dump_vpd_ident_type(
1104 struct t10_vpd *vpd,
1105 unsigned char *p_buf,
1106 int p_buf_len)
1107 {
1108 unsigned char buf[VPD_TMP_BUF_SIZE];
1109 int ret = 0;
1110 int len;
1111
1112 memset(buf, 0, VPD_TMP_BUF_SIZE);
1113 len = sprintf(buf, "T10 VPD Identifier Type: ");
1114
1115 switch (vpd->device_identifier_type) {
1116 case 0x00:
1117 sprintf(buf+len, "Vendor specific\n");
1118 break;
1119 case 0x01:
1120 sprintf(buf+len, "T10 Vendor ID based\n");
1121 break;
1122 case 0x02:
1123 sprintf(buf+len, "EUI-64 based\n");
1124 break;
1125 case 0x03:
1126 sprintf(buf+len, "NAA\n");
1127 break;
1128 case 0x04:
1129 sprintf(buf+len, "Relative target port identifier\n");
1130 break;
1131 case 0x08:
1132 sprintf(buf+len, "SCSI name string\n");
1133 break;
1134 default:
1135 sprintf(buf+len, "Unsupported: 0x%02x\n",
1136 vpd->device_identifier_type);
1137 ret = -EINVAL;
1138 break;
1139 }
1140
1141 if (p_buf) {
1142 if (p_buf_len < strlen(buf)+1)
1143 return -EINVAL;
1144 strncpy(p_buf, buf, p_buf_len);
1145 } else {
1146 pr_debug("%s", buf);
1147 }
1148
1149 return ret;
1150 }
1151
1152 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1153 {
1154 /*
1155 * The VPD identifier type..
1156 *
1157 * from spc3r23.pdf Section 7.6.3.1 Table 298
1158 */
1159 vpd->device_identifier_type = (page_83[1] & 0x0f);
1160 return transport_dump_vpd_ident_type(vpd, NULL, 0);
1161 }
1162 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1163
1164 int transport_dump_vpd_ident(
1165 struct t10_vpd *vpd,
1166 unsigned char *p_buf,
1167 int p_buf_len)
1168 {
1169 unsigned char buf[VPD_TMP_BUF_SIZE];
1170 int ret = 0;
1171
1172 memset(buf, 0, VPD_TMP_BUF_SIZE);
1173
1174 switch (vpd->device_identifier_code_set) {
1175 case 0x01: /* Binary */
1176 snprintf(buf, sizeof(buf),
1177 "T10 VPD Binary Device Identifier: %s\n",
1178 &vpd->device_identifier[0]);
1179 break;
1180 case 0x02: /* ASCII */
1181 snprintf(buf, sizeof(buf),
1182 "T10 VPD ASCII Device Identifier: %s\n",
1183 &vpd->device_identifier[0]);
1184 break;
1185 case 0x03: /* UTF-8 */
1186 snprintf(buf, sizeof(buf),
1187 "T10 VPD UTF-8 Device Identifier: %s\n",
1188 &vpd->device_identifier[0]);
1189 break;
1190 default:
1191 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1192 " 0x%02x", vpd->device_identifier_code_set);
1193 ret = -EINVAL;
1194 break;
1195 }
1196
1197 if (p_buf)
1198 strncpy(p_buf, buf, p_buf_len);
1199 else
1200 pr_debug("%s", buf);
1201
1202 return ret;
1203 }
1204
1205 int
1206 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1207 {
1208 static const char hex_str[] = "0123456789abcdef";
1209 int j = 0, i = 4; /* offset to start of the identifier */
1210
1211 /*
1212 * The VPD Code Set (encoding)
1213 *
1214 * from spc3r23.pdf Section 7.6.3.1 Table 296
1215 */
1216 vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1217 switch (vpd->device_identifier_code_set) {
1218 case 0x01: /* Binary */
1219 vpd->device_identifier[j++] =
1220 hex_str[vpd->device_identifier_type];
1221 while (i < (4 + page_83[3])) {
1222 vpd->device_identifier[j++] =
1223 hex_str[(page_83[i] & 0xf0) >> 4];
1224 vpd->device_identifier[j++] =
1225 hex_str[page_83[i] & 0x0f];
1226 i++;
1227 }
1228 break;
1229 case 0x02: /* ASCII */
1230 case 0x03: /* UTF-8 */
1231 while (i < (4 + page_83[3]))
1232 vpd->device_identifier[j++] = page_83[i++];
1233 break;
1234 default:
1235 break;
1236 }
1237
1238 return transport_dump_vpd_ident(vpd, NULL, 0);
1239 }
1240 EXPORT_SYMBOL(transport_set_vpd_ident);
1241
1242 static sense_reason_t
1243 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1244 unsigned int size)
1245 {
1246 u32 mtl;
1247
1248 if (!cmd->se_tfo->max_data_sg_nents)
1249 return TCM_NO_SENSE;
1250 /*
1251 * Check if fabric enforced maximum SGL entries per I/O descriptor
1252 * exceeds se_cmd->data_length. If true, set SCF_UNDERFLOW_BIT +
1253 * residual_count and reduce original cmd->data_length to maximum
1254 * length based on single PAGE_SIZE entry scatter-lists.
1255 */
1256 mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1257 if (cmd->data_length > mtl) {
1258 /*
1259 * If an existing CDB overflow is present, calculate new residual
1260 * based on CDB size minus fabric maximum transfer length.
1261 *
1262 * If an existing CDB underflow is present, calculate new residual
1263 * based on original cmd->data_length minus fabric maximum transfer
1264 * length.
1265 *
1266 * Otherwise, set the underflow residual based on cmd->data_length
1267 * minus fabric maximum transfer length.
1268 */
1269 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1270 cmd->residual_count = (size - mtl);
1271 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1272 u32 orig_dl = size + cmd->residual_count;
1273 cmd->residual_count = (orig_dl - mtl);
1274 } else {
1275 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1276 cmd->residual_count = (cmd->data_length - mtl);
1277 }
1278 cmd->data_length = mtl;
1279 /*
1280 * Reset sbc_check_prot() calculated protection payload
1281 * length based upon the new smaller MTL.
1282 */
1283 if (cmd->prot_length) {
1284 u32 sectors = (mtl / dev->dev_attrib.block_size);
1285 cmd->prot_length = dev->prot_length * sectors;
1286 }
1287 }
1288 return TCM_NO_SENSE;
1289 }
1290
1291 /**
1292 * target_cmd_size_check - Check whether there will be a residual.
1293 * @cmd: SCSI command.
1294 * @size: Data buffer size derived from CDB. The data buffer size provided by
1295 * the SCSI transport driver is available in @cmd->data_length.
1296 *
1297 * Compare the data buffer size from the CDB with the data buffer limit from the transport
1298 * header. Set @cmd->residual_count and SCF_OVERFLOW_BIT or SCF_UNDERFLOW_BIT if necessary.
1299 *
1300 * Note: target drivers set @cmd->data_length by calling transport_init_se_cmd().
1301 *
1302 * Return: TCM_NO_SENSE
1303 */
1304 sense_reason_t
1305 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1306 {
1307 struct se_device *dev = cmd->se_dev;
1308
1309 if (cmd->unknown_data_length) {
1310 cmd->data_length = size;
1311 } else if (size != cmd->data_length) {
1312 pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1313 " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1314 " 0x%02x\n", cmd->se_tfo->fabric_name,
1315 cmd->data_length, size, cmd->t_task_cdb[0]);
1316
1317 if (cmd->data_direction == DMA_TO_DEVICE) {
1318 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1319 pr_err_ratelimited("Rejecting underflow/overflow"
1320 " for WRITE data CDB\n");
1321 return TCM_INVALID_CDB_FIELD;
1322 }
1323 /*
1324 * Some fabric drivers like iscsi-target still expect to
1325 * always reject overflow writes. Reject this case until
1326 * full fabric driver level support for overflow writes
1327 * is introduced tree-wide.
1328 */
1329 if (size > cmd->data_length) {
1330 pr_err_ratelimited("Rejecting overflow for"
1331 " WRITE control CDB\n");
1332 return TCM_INVALID_CDB_FIELD;
1333 }
1334 }
1335 /*
1336 * Reject READ_* or WRITE_* with overflow/underflow for
1337 * type SCF_SCSI_DATA_CDB.
1338 */
1339 if (dev->dev_attrib.block_size != 512) {
1340 pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1341 " CDB on non 512-byte sector setup subsystem"
1342 " plugin: %s\n", dev->transport->name);
1343 /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1344 return TCM_INVALID_CDB_FIELD;
1345 }
1346 /*
1347 * For the overflow case keep the existing fabric provided
1348 * ->data_length. Otherwise for the underflow case, reset
1349 * ->data_length to the smaller SCSI expected data transfer
1350 * length.
1351 */
1352 if (size > cmd->data_length) {
1353 cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1354 cmd->residual_count = (size - cmd->data_length);
1355 } else {
1356 cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1357 cmd->residual_count = (cmd->data_length - size);
1358 cmd->data_length = size;
1359 }
1360 }
1361
1362 return target_check_max_data_sg_nents(cmd, dev, size);
1363
1364 }
1365
1366 /*
1367 * Used by fabric modules containing a local struct se_cmd within their
1368 * fabric dependent per I/O descriptor.
1369 *
1370 * Preserves the value of @cmd->tag.
1371 */
1372 void transport_init_se_cmd(
1373 struct se_cmd *cmd,
1374 const struct target_core_fabric_ops *tfo,
1375 struct se_session *se_sess,
1376 u32 data_length,
1377 int data_direction,
1378 int task_attr,
1379 unsigned char *sense_buffer, u64 unpacked_lun)
1380 {
1381 INIT_LIST_HEAD(&cmd->se_delayed_node);
1382 INIT_LIST_HEAD(&cmd->se_qf_node);
1383 INIT_LIST_HEAD(&cmd->se_cmd_list);
1384 INIT_LIST_HEAD(&cmd->state_list);
1385 init_completion(&cmd->t_transport_stop_comp);
1386 cmd->free_compl = NULL;
1387 cmd->abrt_compl = NULL;
1388 spin_lock_init(&cmd->t_state_lock);
1389 INIT_WORK(&cmd->work, NULL);
1390 kref_init(&cmd->cmd_kref);
1391
1392 cmd->se_tfo = tfo;
1393 cmd->se_sess = se_sess;
1394 cmd->data_length = data_length;
1395 cmd->data_direction = data_direction;
1396 cmd->sam_task_attr = task_attr;
1397 cmd->sense_buffer = sense_buffer;
1398 cmd->orig_fe_lun = unpacked_lun;
1399
1400 if (!(cmd->se_cmd_flags & SCF_USE_CPUID))
1401 cmd->cpuid = smp_processor_id();
1402
1403 cmd->state_active = false;
1404 }
1405 EXPORT_SYMBOL(transport_init_se_cmd);
1406
1407 static sense_reason_t
1408 transport_check_alloc_task_attr(struct se_cmd *cmd)
1409 {
1410 struct se_device *dev = cmd->se_dev;
1411
1412 /*
1413 * Check if SAM Task Attribute emulation is enabled for this
1414 * struct se_device storage object
1415 */
1416 if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1417 return 0;
1418
1419 if (cmd->sam_task_attr == TCM_ACA_TAG) {
1420 pr_debug("SAM Task Attribute ACA"
1421 " emulation is not supported\n");
1422 return TCM_INVALID_CDB_FIELD;
1423 }
1424
1425 return 0;
1426 }
1427
1428 sense_reason_t
1429 target_cmd_init_cdb(struct se_cmd *cmd, unsigned char *cdb)
1430 {
1431 sense_reason_t ret;
1432
1433 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1434 /*
1435 * Ensure that the received CDB is less than the max (252 + 8) bytes
1436 * for VARIABLE_LENGTH_CMD
1437 */
1438 if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1439 pr_err("Received SCSI CDB with command_size: %d that"
1440 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1441 scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1442 ret = TCM_INVALID_CDB_FIELD;
1443 goto err;
1444 }
1445 /*
1446 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1447 * allocate the additional extended CDB buffer now.. Otherwise
1448 * setup the pointer from __t_task_cdb to t_task_cdb.
1449 */
1450 if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1451 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1452 GFP_KERNEL);
1453 if (!cmd->t_task_cdb) {
1454 pr_err("Unable to allocate cmd->t_task_cdb"
1455 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1456 scsi_command_size(cdb),
1457 (unsigned long)sizeof(cmd->__t_task_cdb));
1458 ret = TCM_OUT_OF_RESOURCES;
1459 goto err;
1460 }
1461 }
1462 /*
1463 * Copy the original CDB into cmd->
1464 */
1465 memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1466
1467 trace_target_sequencer_start(cmd);
1468 return 0;
1469
1470 err:
1471 /*
1472 * Copy the CDB here to allow trace_target_cmd_complete() to
1473 * print the cdb to the trace buffers.
1474 */
1475 memcpy(cmd->t_task_cdb, cdb, min(scsi_command_size(cdb),
1476 (unsigned int)TCM_MAX_COMMAND_SIZE));
1477 return ret;
1478 }
1479 EXPORT_SYMBOL(target_cmd_init_cdb);
1480
1481 sense_reason_t
1482 target_cmd_parse_cdb(struct se_cmd *cmd)
1483 {
1484 struct se_device *dev = cmd->se_dev;
1485 sense_reason_t ret;
1486
1487 ret = dev->transport->parse_cdb(cmd);
1488 if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1489 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1490 cmd->se_tfo->fabric_name,
1491 cmd->se_sess->se_node_acl->initiatorname,
1492 cmd->t_task_cdb[0]);
1493 if (ret)
1494 return ret;
1495
1496 ret = transport_check_alloc_task_attr(cmd);
1497 if (ret)
1498 return ret;
1499
1500 cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1501 atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1502 return 0;
1503 }
1504 EXPORT_SYMBOL(target_cmd_parse_cdb);
1505
1506 /*
1507 * Used by fabric module frontends to queue tasks directly.
1508 * May only be used from process context.
1509 */
1510 int transport_handle_cdb_direct(
1511 struct se_cmd *cmd)
1512 {
1513 sense_reason_t ret;
1514
1515 if (!cmd->se_lun) {
1516 dump_stack();
1517 pr_err("cmd->se_lun is NULL\n");
1518 return -EINVAL;
1519 }
1520 if (in_interrupt()) {
1521 dump_stack();
1522 pr_err("transport_generic_handle_cdb cannot be called"
1523 " from interrupt context\n");
1524 return -EINVAL;
1525 }
1526 /*
1527 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1528 * outstanding descriptors are handled correctly during shutdown via
1529 * transport_wait_for_tasks()
1530 *
1531 * Also, we don't take cmd->t_state_lock here as we only expect
1532 * this to be called for initial descriptor submission.
1533 */
1534 cmd->t_state = TRANSPORT_NEW_CMD;
1535 cmd->transport_state |= CMD_T_ACTIVE;
1536
1537 /*
1538 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1539 * so follow TRANSPORT_NEW_CMD processing thread context usage
1540 * and call transport_generic_request_failure() if necessary..
1541 */
1542 ret = transport_generic_new_cmd(cmd);
1543 if (ret)
1544 transport_generic_request_failure(cmd, ret);
1545 return 0;
1546 }
1547 EXPORT_SYMBOL(transport_handle_cdb_direct);
1548
1549 sense_reason_t
1550 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1551 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1552 {
1553 if (!sgl || !sgl_count)
1554 return 0;
1555
1556 /*
1557 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1558 * scatterlists already have been set to follow what the fabric
1559 * passes for the original expected data transfer length.
1560 */
1561 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1562 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1563 " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1564 return TCM_INVALID_CDB_FIELD;
1565 }
1566
1567 cmd->t_data_sg = sgl;
1568 cmd->t_data_nents = sgl_count;
1569 cmd->t_bidi_data_sg = sgl_bidi;
1570 cmd->t_bidi_data_nents = sgl_bidi_count;
1571
1572 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1573 return 0;
1574 }
1575
1576 /**
1577 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1578 * se_cmd + use pre-allocated SGL memory.
1579 *
1580 * @se_cmd: command descriptor to submit
1581 * @se_sess: associated se_sess for endpoint
1582 * @cdb: pointer to SCSI CDB
1583 * @sense: pointer to SCSI sense buffer
1584 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1585 * @data_length: fabric expected data transfer length
1586 * @task_attr: SAM task attribute
1587 * @data_dir: DMA data direction
1588 * @flags: flags for command submission from target_sc_flags_tables
1589 * @sgl: struct scatterlist memory for unidirectional mapping
1590 * @sgl_count: scatterlist count for unidirectional mapping
1591 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1592 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1593 * @sgl_prot: struct scatterlist memory protection information
1594 * @sgl_prot_count: scatterlist count for protection information
1595 *
1596 * Task tags are supported if the caller has set @se_cmd->tag.
1597 *
1598 * Returns non zero to signal active I/O shutdown failure. All other
1599 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1600 * but still return zero here.
1601 *
1602 * This may only be called from process context, and also currently
1603 * assumes internal allocation of fabric payload buffer by target-core.
1604 */
1605 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1606 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1607 u32 data_length, int task_attr, int data_dir, int flags,
1608 struct scatterlist *sgl, u32 sgl_count,
1609 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1610 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1611 {
1612 struct se_portal_group *se_tpg;
1613 sense_reason_t rc;
1614 int ret;
1615
1616 se_tpg = se_sess->se_tpg;
1617 BUG_ON(!se_tpg);
1618 BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1619 BUG_ON(in_interrupt());
1620
1621 if (flags & TARGET_SCF_USE_CPUID)
1622 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1623 /*
1624 * Initialize se_cmd for target operation. From this point
1625 * exceptions are handled by sending exception status via
1626 * target_core_fabric_ops->queue_status() callback
1627 */
1628 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1629 data_length, data_dir, task_attr, sense,
1630 unpacked_lun);
1631
1632 if (flags & TARGET_SCF_UNKNOWN_SIZE)
1633 se_cmd->unknown_data_length = 1;
1634 /*
1635 * Obtain struct se_cmd->cmd_kref reference. A second kref_get here is
1636 * necessary for fabrics using TARGET_SCF_ACK_KREF that expect a second
1637 * kref_put() to happen during fabric packet acknowledgement.
1638 */
1639 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1640 if (ret)
1641 return ret;
1642 /*
1643 * Signal bidirectional data payloads to target-core
1644 */
1645 if (flags & TARGET_SCF_BIDI_OP)
1646 se_cmd->se_cmd_flags |= SCF_BIDI;
1647
1648 rc = target_cmd_init_cdb(se_cmd, cdb);
1649 if (rc) {
1650 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1651 target_put_sess_cmd(se_cmd);
1652 return 0;
1653 }
1654
1655 /*
1656 * Locate se_lun pointer and attach it to struct se_cmd
1657 */
1658 rc = transport_lookup_cmd_lun(se_cmd);
1659 if (rc) {
1660 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1661 target_put_sess_cmd(se_cmd);
1662 return 0;
1663 }
1664
1665 rc = target_cmd_parse_cdb(se_cmd);
1666 if (rc != 0) {
1667 transport_generic_request_failure(se_cmd, rc);
1668 return 0;
1669 }
1670
1671 /*
1672 * Save pointers for SGLs containing protection information,
1673 * if present.
1674 */
1675 if (sgl_prot_count) {
1676 se_cmd->t_prot_sg = sgl_prot;
1677 se_cmd->t_prot_nents = sgl_prot_count;
1678 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1679 }
1680
1681 /*
1682 * When a non zero sgl_count has been passed perform SGL passthrough
1683 * mapping for pre-allocated fabric memory instead of having target
1684 * core perform an internal SGL allocation..
1685 */
1686 if (sgl_count != 0) {
1687 BUG_ON(!sgl);
1688
1689 /*
1690 * A work-around for tcm_loop as some userspace code via
1691 * scsi-generic do not memset their associated read buffers,
1692 * so go ahead and do that here for type non-data CDBs. Also
1693 * note that this is currently guaranteed to be a single SGL
1694 * for this case by target core in target_setup_cmd_from_cdb()
1695 * -> transport_generic_cmd_sequencer().
1696 */
1697 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1698 se_cmd->data_direction == DMA_FROM_DEVICE) {
1699 unsigned char *buf = NULL;
1700
1701 if (sgl)
1702 buf = kmap(sg_page(sgl)) + sgl->offset;
1703
1704 if (buf) {
1705 memset(buf, 0, sgl->length);
1706 kunmap(sg_page(sgl));
1707 }
1708 }
1709
1710 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1711 sgl_bidi, sgl_bidi_count);
1712 if (rc != 0) {
1713 transport_generic_request_failure(se_cmd, rc);
1714 return 0;
1715 }
1716 }
1717
1718 /*
1719 * Check if we need to delay processing because of ALUA
1720 * Active/NonOptimized primary access state..
1721 */
1722 core_alua_check_nonop_delay(se_cmd);
1723
1724 transport_handle_cdb_direct(se_cmd);
1725 return 0;
1726 }
1727 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1728
1729 /**
1730 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1731 *
1732 * @se_cmd: command descriptor to submit
1733 * @se_sess: associated se_sess for endpoint
1734 * @cdb: pointer to SCSI CDB
1735 * @sense: pointer to SCSI sense buffer
1736 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1737 * @data_length: fabric expected data transfer length
1738 * @task_attr: SAM task attribute
1739 * @data_dir: DMA data direction
1740 * @flags: flags for command submission from target_sc_flags_tables
1741 *
1742 * Task tags are supported if the caller has set @se_cmd->tag.
1743 *
1744 * Returns non zero to signal active I/O shutdown failure. All other
1745 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1746 * but still return zero here.
1747 *
1748 * This may only be called from process context, and also currently
1749 * assumes internal allocation of fabric payload buffer by target-core.
1750 *
1751 * It also assumes interal target core SGL memory allocation.
1752 */
1753 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1754 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1755 u32 data_length, int task_attr, int data_dir, int flags)
1756 {
1757 return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1758 unpacked_lun, data_length, task_attr, data_dir,
1759 flags, NULL, 0, NULL, 0, NULL, 0);
1760 }
1761 EXPORT_SYMBOL(target_submit_cmd);
1762
1763 static void target_complete_tmr_failure(struct work_struct *work)
1764 {
1765 struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1766
1767 se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1768 se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1769
1770 transport_lun_remove_cmd(se_cmd);
1771 transport_cmd_check_stop_to_fabric(se_cmd);
1772 }
1773
1774 /**
1775 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1776 * for TMR CDBs
1777 *
1778 * @se_cmd: command descriptor to submit
1779 * @se_sess: associated se_sess for endpoint
1780 * @sense: pointer to SCSI sense buffer
1781 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1782 * @fabric_tmr_ptr: fabric context for TMR req
1783 * @tm_type: Type of TM request
1784 * @gfp: gfp type for caller
1785 * @tag: referenced task tag for TMR_ABORT_TASK
1786 * @flags: submit cmd flags
1787 *
1788 * Callable from all contexts.
1789 **/
1790
1791 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1792 unsigned char *sense, u64 unpacked_lun,
1793 void *fabric_tmr_ptr, unsigned char tm_type,
1794 gfp_t gfp, u64 tag, int flags)
1795 {
1796 struct se_portal_group *se_tpg;
1797 int ret;
1798
1799 se_tpg = se_sess->se_tpg;
1800 BUG_ON(!se_tpg);
1801
1802 transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1803 0, DMA_NONE, TCM_SIMPLE_TAG, sense, unpacked_lun);
1804 /*
1805 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1806 * allocation failure.
1807 */
1808 ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1809 if (ret < 0)
1810 return -ENOMEM;
1811
1812 if (tm_type == TMR_ABORT_TASK)
1813 se_cmd->se_tmr_req->ref_task_tag = tag;
1814
1815 /* See target_submit_cmd for commentary */
1816 ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1817 if (ret) {
1818 core_tmr_release_req(se_cmd->se_tmr_req);
1819 return ret;
1820 }
1821
1822 ret = transport_lookup_tmr_lun(se_cmd);
1823 if (ret)
1824 goto failure;
1825
1826 transport_generic_handle_tmr(se_cmd);
1827 return 0;
1828
1829 /*
1830 * For callback during failure handling, push this work off
1831 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1832 */
1833 failure:
1834 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1835 schedule_work(&se_cmd->work);
1836 return 0;
1837 }
1838 EXPORT_SYMBOL(target_submit_tmr);
1839
1840 /*
1841 * Handle SAM-esque emulation for generic transport request failures.
1842 */
1843 void transport_generic_request_failure(struct se_cmd *cmd,
1844 sense_reason_t sense_reason)
1845 {
1846 int ret = 0, post_ret;
1847
1848 pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
1849 sense_reason);
1850 target_show_cmd("-----[ ", cmd);
1851
1852 /*
1853 * For SAM Task Attribute emulation for failed struct se_cmd
1854 */
1855 transport_complete_task_attr(cmd);
1856
1857 if (cmd->transport_complete_callback)
1858 cmd->transport_complete_callback(cmd, false, &post_ret);
1859
1860 if (cmd->transport_state & CMD_T_ABORTED) {
1861 INIT_WORK(&cmd->work, target_abort_work);
1862 queue_work(target_completion_wq, &cmd->work);
1863 return;
1864 }
1865
1866 switch (sense_reason) {
1867 case TCM_NON_EXISTENT_LUN:
1868 case TCM_UNSUPPORTED_SCSI_OPCODE:
1869 case TCM_INVALID_CDB_FIELD:
1870 case TCM_INVALID_PARAMETER_LIST:
1871 case TCM_PARAMETER_LIST_LENGTH_ERROR:
1872 case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1873 case TCM_UNKNOWN_MODE_PAGE:
1874 case TCM_WRITE_PROTECTED:
1875 case TCM_ADDRESS_OUT_OF_RANGE:
1876 case TCM_CHECK_CONDITION_ABORT_CMD:
1877 case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1878 case TCM_CHECK_CONDITION_NOT_READY:
1879 case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1880 case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1881 case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1882 case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1883 case TCM_TOO_MANY_TARGET_DESCS:
1884 case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
1885 case TCM_TOO_MANY_SEGMENT_DESCS:
1886 case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
1887 break;
1888 case TCM_OUT_OF_RESOURCES:
1889 cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
1890 goto queue_status;
1891 case TCM_LUN_BUSY:
1892 cmd->scsi_status = SAM_STAT_BUSY;
1893 goto queue_status;
1894 case TCM_RESERVATION_CONFLICT:
1895 /*
1896 * No SENSE Data payload for this case, set SCSI Status
1897 * and queue the response to $FABRIC_MOD.
1898 *
1899 * Uses linux/include/scsi/scsi.h SAM status codes defs
1900 */
1901 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1902 /*
1903 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1904 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1905 * CONFLICT STATUS.
1906 *
1907 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1908 */
1909 if (cmd->se_sess &&
1910 cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl
1911 == TARGET_UA_INTLCK_CTRL_ESTABLISH_UA) {
1912 target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1913 cmd->orig_fe_lun, 0x2C,
1914 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1915 }
1916
1917 goto queue_status;
1918 default:
1919 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1920 cmd->t_task_cdb[0], sense_reason);
1921 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1922 break;
1923 }
1924
1925 ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1926 if (ret)
1927 goto queue_full;
1928
1929 check_stop:
1930 transport_lun_remove_cmd(cmd);
1931 transport_cmd_check_stop_to_fabric(cmd);
1932 return;
1933
1934 queue_status:
1935 trace_target_cmd_complete(cmd);
1936 ret = cmd->se_tfo->queue_status(cmd);
1937 if (!ret)
1938 goto check_stop;
1939 queue_full:
1940 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
1941 }
1942 EXPORT_SYMBOL(transport_generic_request_failure);
1943
1944 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1945 {
1946 sense_reason_t ret;
1947
1948 if (!cmd->execute_cmd) {
1949 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1950 goto err;
1951 }
1952 if (do_checks) {
1953 /*
1954 * Check for an existing UNIT ATTENTION condition after
1955 * target_handle_task_attr() has done SAM task attr
1956 * checking, and possibly have already defered execution
1957 * out to target_restart_delayed_cmds() context.
1958 */
1959 ret = target_scsi3_ua_check(cmd);
1960 if (ret)
1961 goto err;
1962
1963 ret = target_alua_state_check(cmd);
1964 if (ret)
1965 goto err;
1966
1967 ret = target_check_reservation(cmd);
1968 if (ret) {
1969 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1970 goto err;
1971 }
1972 }
1973
1974 ret = cmd->execute_cmd(cmd);
1975 if (!ret)
1976 return;
1977 err:
1978 spin_lock_irq(&cmd->t_state_lock);
1979 cmd->transport_state &= ~CMD_T_SENT;
1980 spin_unlock_irq(&cmd->t_state_lock);
1981
1982 transport_generic_request_failure(cmd, ret);
1983 }
1984
1985 static int target_write_prot_action(struct se_cmd *cmd)
1986 {
1987 u32 sectors;
1988 /*
1989 * Perform WRITE_INSERT of PI using software emulation when backend
1990 * device has PI enabled, if the transport has not already generated
1991 * PI using hardware WRITE_INSERT offload.
1992 */
1993 switch (cmd->prot_op) {
1994 case TARGET_PROT_DOUT_INSERT:
1995 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1996 sbc_dif_generate(cmd);
1997 break;
1998 case TARGET_PROT_DOUT_STRIP:
1999 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
2000 break;
2001
2002 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
2003 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2004 sectors, 0, cmd->t_prot_sg, 0);
2005 if (unlikely(cmd->pi_err)) {
2006 spin_lock_irq(&cmd->t_state_lock);
2007 cmd->transport_state &= ~CMD_T_SENT;
2008 spin_unlock_irq(&cmd->t_state_lock);
2009 transport_generic_request_failure(cmd, cmd->pi_err);
2010 return -1;
2011 }
2012 break;
2013 default:
2014 break;
2015 }
2016
2017 return 0;
2018 }
2019
2020 static bool target_handle_task_attr(struct se_cmd *cmd)
2021 {
2022 struct se_device *dev = cmd->se_dev;
2023
2024 if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2025 return false;
2026
2027 cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
2028
2029 /*
2030 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
2031 * to allow the passed struct se_cmd list of tasks to the front of the list.
2032 */
2033 switch (cmd->sam_task_attr) {
2034 case TCM_HEAD_TAG:
2035 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
2036 cmd->t_task_cdb[0]);
2037 return false;
2038 case TCM_ORDERED_TAG:
2039 atomic_inc_mb(&dev->dev_ordered_sync);
2040
2041 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
2042 cmd->t_task_cdb[0]);
2043
2044 /*
2045 * Execute an ORDERED command if no other older commands
2046 * exist that need to be completed first.
2047 */
2048 if (!atomic_read(&dev->simple_cmds))
2049 return false;
2050 break;
2051 default:
2052 /*
2053 * For SIMPLE and UNTAGGED Task Attribute commands
2054 */
2055 atomic_inc_mb(&dev->simple_cmds);
2056 break;
2057 }
2058
2059 if (atomic_read(&dev->dev_ordered_sync) == 0)
2060 return false;
2061
2062 spin_lock(&dev->delayed_cmd_lock);
2063 list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
2064 spin_unlock(&dev->delayed_cmd_lock);
2065
2066 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
2067 cmd->t_task_cdb[0], cmd->sam_task_attr);
2068 return true;
2069 }
2070
2071 void target_execute_cmd(struct se_cmd *cmd)
2072 {
2073 /*
2074 * Determine if frontend context caller is requesting the stopping of
2075 * this command for frontend exceptions.
2076 *
2077 * If the received CDB has already been aborted stop processing it here.
2078 */
2079 if (target_cmd_interrupted(cmd))
2080 return;
2081
2082 spin_lock_irq(&cmd->t_state_lock);
2083 cmd->t_state = TRANSPORT_PROCESSING;
2084 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
2085 spin_unlock_irq(&cmd->t_state_lock);
2086
2087 if (target_write_prot_action(cmd))
2088 return;
2089
2090 if (target_handle_task_attr(cmd)) {
2091 spin_lock_irq(&cmd->t_state_lock);
2092 cmd->transport_state &= ~CMD_T_SENT;
2093 spin_unlock_irq(&cmd->t_state_lock);
2094 return;
2095 }
2096
2097 __target_execute_cmd(cmd, true);
2098 }
2099 EXPORT_SYMBOL(target_execute_cmd);
2100
2101 /*
2102 * Process all commands up to the last received ORDERED task attribute which
2103 * requires another blocking boundary
2104 */
2105 static void target_restart_delayed_cmds(struct se_device *dev)
2106 {
2107 for (;;) {
2108 struct se_cmd *cmd;
2109
2110 spin_lock(&dev->delayed_cmd_lock);
2111 if (list_empty(&dev->delayed_cmd_list)) {
2112 spin_unlock(&dev->delayed_cmd_lock);
2113 break;
2114 }
2115
2116 cmd = list_entry(dev->delayed_cmd_list.next,
2117 struct se_cmd, se_delayed_node);
2118 list_del(&cmd->se_delayed_node);
2119 spin_unlock(&dev->delayed_cmd_lock);
2120
2121 cmd->transport_state |= CMD_T_SENT;
2122
2123 __target_execute_cmd(cmd, true);
2124
2125 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
2126 break;
2127 }
2128 }
2129
2130 /*
2131 * Called from I/O completion to determine which dormant/delayed
2132 * and ordered cmds need to have their tasks added to the execution queue.
2133 */
2134 static void transport_complete_task_attr(struct se_cmd *cmd)
2135 {
2136 struct se_device *dev = cmd->se_dev;
2137
2138 if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2139 return;
2140
2141 if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2142 goto restart;
2143
2144 if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
2145 atomic_dec_mb(&dev->simple_cmds);
2146 dev->dev_cur_ordered_id++;
2147 } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
2148 dev->dev_cur_ordered_id++;
2149 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
2150 dev->dev_cur_ordered_id);
2151 } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2152 atomic_dec_mb(&dev->dev_ordered_sync);
2153
2154 dev->dev_cur_ordered_id++;
2155 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
2156 dev->dev_cur_ordered_id);
2157 }
2158 cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2159
2160 restart:
2161 target_restart_delayed_cmds(dev);
2162 }
2163
2164 static void transport_complete_qf(struct se_cmd *cmd)
2165 {
2166 int ret = 0;
2167
2168 transport_complete_task_attr(cmd);
2169 /*
2170 * If a fabric driver ->write_pending() or ->queue_data_in() callback
2171 * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2172 * the same callbacks should not be retried. Return CHECK_CONDITION
2173 * if a scsi_status is not already set.
2174 *
2175 * If a fabric driver ->queue_status() has returned non zero, always
2176 * keep retrying no matter what..
2177 */
2178 if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2179 if (cmd->scsi_status)
2180 goto queue_status;
2181
2182 translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2183 goto queue_status;
2184 }
2185
2186 /*
2187 * Check if we need to send a sense buffer from
2188 * the struct se_cmd in question. We do NOT want
2189 * to take this path of the IO has been marked as
2190 * needing to be treated like a "normal read". This
2191 * is the case if it's a tape read, and either the
2192 * FM, EOM, or ILI bits are set, but there is no
2193 * sense data.
2194 */
2195 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2196 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2197 goto queue_status;
2198
2199 switch (cmd->data_direction) {
2200 case DMA_FROM_DEVICE:
2201 /* queue status if not treating this as a normal read */
2202 if (cmd->scsi_status &&
2203 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2204 goto queue_status;
2205
2206 trace_target_cmd_complete(cmd);
2207 ret = cmd->se_tfo->queue_data_in(cmd);
2208 break;
2209 case DMA_TO_DEVICE:
2210 if (cmd->se_cmd_flags & SCF_BIDI) {
2211 ret = cmd->se_tfo->queue_data_in(cmd);
2212 break;
2213 }
2214 fallthrough;
2215 case DMA_NONE:
2216 queue_status:
2217 trace_target_cmd_complete(cmd);
2218 ret = cmd->se_tfo->queue_status(cmd);
2219 break;
2220 default:
2221 break;
2222 }
2223
2224 if (ret < 0) {
2225 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2226 return;
2227 }
2228 transport_lun_remove_cmd(cmd);
2229 transport_cmd_check_stop_to_fabric(cmd);
2230 }
2231
2232 static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2233 int err, bool write_pending)
2234 {
2235 /*
2236 * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2237 * ->queue_data_in() callbacks from new process context.
2238 *
2239 * Otherwise for other errors, transport_complete_qf() will send
2240 * CHECK_CONDITION via ->queue_status() instead of attempting to
2241 * retry associated fabric driver data-transfer callbacks.
2242 */
2243 if (err == -EAGAIN || err == -ENOMEM) {
2244 cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2245 TRANSPORT_COMPLETE_QF_OK;
2246 } else {
2247 pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2248 cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2249 }
2250
2251 spin_lock_irq(&dev->qf_cmd_lock);
2252 list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2253 atomic_inc_mb(&dev->dev_qf_count);
2254 spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2255
2256 schedule_work(&cmd->se_dev->qf_work_queue);
2257 }
2258
2259 static bool target_read_prot_action(struct se_cmd *cmd)
2260 {
2261 switch (cmd->prot_op) {
2262 case TARGET_PROT_DIN_STRIP:
2263 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2264 u32 sectors = cmd->data_length >>
2265 ilog2(cmd->se_dev->dev_attrib.block_size);
2266
2267 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2268 sectors, 0, cmd->t_prot_sg,
2269 0);
2270 if (cmd->pi_err)
2271 return true;
2272 }
2273 break;
2274 case TARGET_PROT_DIN_INSERT:
2275 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2276 break;
2277
2278 sbc_dif_generate(cmd);
2279 break;
2280 default:
2281 break;
2282 }
2283
2284 return false;
2285 }
2286
2287 static void target_complete_ok_work(struct work_struct *work)
2288 {
2289 struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2290 int ret;
2291
2292 /*
2293 * Check if we need to move delayed/dormant tasks from cmds on the
2294 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2295 * Attribute.
2296 */
2297 transport_complete_task_attr(cmd);
2298
2299 /*
2300 * Check to schedule QUEUE_FULL work, or execute an existing
2301 * cmd->transport_qf_callback()
2302 */
2303 if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2304 schedule_work(&cmd->se_dev->qf_work_queue);
2305
2306 /*
2307 * Check if we need to send a sense buffer from
2308 * the struct se_cmd in question. We do NOT want
2309 * to take this path of the IO has been marked as
2310 * needing to be treated like a "normal read". This
2311 * is the case if it's a tape read, and either the
2312 * FM, EOM, or ILI bits are set, but there is no
2313 * sense data.
2314 */
2315 if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2316 cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2317 WARN_ON(!cmd->scsi_status);
2318 ret = transport_send_check_condition_and_sense(
2319 cmd, 0, 1);
2320 if (ret)
2321 goto queue_full;
2322
2323 transport_lun_remove_cmd(cmd);
2324 transport_cmd_check_stop_to_fabric(cmd);
2325 return;
2326 }
2327 /*
2328 * Check for a callback, used by amongst other things
2329 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2330 */
2331 if (cmd->transport_complete_callback) {
2332 sense_reason_t rc;
2333 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2334 bool zero_dl = !(cmd->data_length);
2335 int post_ret = 0;
2336
2337 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2338 if (!rc && !post_ret) {
2339 if (caw && zero_dl)
2340 goto queue_rsp;
2341
2342 return;
2343 } else if (rc) {
2344 ret = transport_send_check_condition_and_sense(cmd,
2345 rc, 0);
2346 if (ret)
2347 goto queue_full;
2348
2349 transport_lun_remove_cmd(cmd);
2350 transport_cmd_check_stop_to_fabric(cmd);
2351 return;
2352 }
2353 }
2354
2355 queue_rsp:
2356 switch (cmd->data_direction) {
2357 case DMA_FROM_DEVICE:
2358 /*
2359 * if this is a READ-type IO, but SCSI status
2360 * is set, then skip returning data and just
2361 * return the status -- unless this IO is marked
2362 * as needing to be treated as a normal read,
2363 * in which case we want to go ahead and return
2364 * the data. This happens, for example, for tape
2365 * reads with the FM, EOM, or ILI bits set, with
2366 * no sense data.
2367 */
2368 if (cmd->scsi_status &&
2369 !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2370 goto queue_status;
2371
2372 atomic_long_add(cmd->data_length,
2373 &cmd->se_lun->lun_stats.tx_data_octets);
2374 /*
2375 * Perform READ_STRIP of PI using software emulation when
2376 * backend had PI enabled, if the transport will not be
2377 * performing hardware READ_STRIP offload.
2378 */
2379 if (target_read_prot_action(cmd)) {
2380 ret = transport_send_check_condition_and_sense(cmd,
2381 cmd->pi_err, 0);
2382 if (ret)
2383 goto queue_full;
2384
2385 transport_lun_remove_cmd(cmd);
2386 transport_cmd_check_stop_to_fabric(cmd);
2387 return;
2388 }
2389
2390 trace_target_cmd_complete(cmd);
2391 ret = cmd->se_tfo->queue_data_in(cmd);
2392 if (ret)
2393 goto queue_full;
2394 break;
2395 case DMA_TO_DEVICE:
2396 atomic_long_add(cmd->data_length,
2397 &cmd->se_lun->lun_stats.rx_data_octets);
2398 /*
2399 * Check if we need to send READ payload for BIDI-COMMAND
2400 */
2401 if (cmd->se_cmd_flags & SCF_BIDI) {
2402 atomic_long_add(cmd->data_length,
2403 &cmd->se_lun->lun_stats.tx_data_octets);
2404 ret = cmd->se_tfo->queue_data_in(cmd);
2405 if (ret)
2406 goto queue_full;
2407 break;
2408 }
2409 fallthrough;
2410 case DMA_NONE:
2411 queue_status:
2412 trace_target_cmd_complete(cmd);
2413 ret = cmd->se_tfo->queue_status(cmd);
2414 if (ret)
2415 goto queue_full;
2416 break;
2417 default:
2418 break;
2419 }
2420
2421 transport_lun_remove_cmd(cmd);
2422 transport_cmd_check_stop_to_fabric(cmd);
2423 return;
2424
2425 queue_full:
2426 pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2427 " data_direction: %d\n", cmd, cmd->data_direction);
2428
2429 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2430 }
2431
2432 void target_free_sgl(struct scatterlist *sgl, int nents)
2433 {
2434 sgl_free_n_order(sgl, nents, 0);
2435 }
2436 EXPORT_SYMBOL(target_free_sgl);
2437
2438 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2439 {
2440 /*
2441 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2442 * emulation, and free + reset pointers if necessary..
2443 */
2444 if (!cmd->t_data_sg_orig)
2445 return;
2446
2447 kfree(cmd->t_data_sg);
2448 cmd->t_data_sg = cmd->t_data_sg_orig;
2449 cmd->t_data_sg_orig = NULL;
2450 cmd->t_data_nents = cmd->t_data_nents_orig;
2451 cmd->t_data_nents_orig = 0;
2452 }
2453
2454 static inline void transport_free_pages(struct se_cmd *cmd)
2455 {
2456 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2457 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2458 cmd->t_prot_sg = NULL;
2459 cmd->t_prot_nents = 0;
2460 }
2461
2462 if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2463 /*
2464 * Release special case READ buffer payload required for
2465 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2466 */
2467 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2468 target_free_sgl(cmd->t_bidi_data_sg,
2469 cmd->t_bidi_data_nents);
2470 cmd->t_bidi_data_sg = NULL;
2471 cmd->t_bidi_data_nents = 0;
2472 }
2473 transport_reset_sgl_orig(cmd);
2474 return;
2475 }
2476 transport_reset_sgl_orig(cmd);
2477
2478 target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2479 cmd->t_data_sg = NULL;
2480 cmd->t_data_nents = 0;
2481
2482 target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2483 cmd->t_bidi_data_sg = NULL;
2484 cmd->t_bidi_data_nents = 0;
2485 }
2486
2487 void *transport_kmap_data_sg(struct se_cmd *cmd)
2488 {
2489 struct scatterlist *sg = cmd->t_data_sg;
2490 struct page **pages;
2491 int i;
2492
2493 /*
2494 * We need to take into account a possible offset here for fabrics like
2495 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2496 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2497 */
2498 if (!cmd->t_data_nents)
2499 return NULL;
2500
2501 BUG_ON(!sg);
2502 if (cmd->t_data_nents == 1)
2503 return kmap(sg_page(sg)) + sg->offset;
2504
2505 /* >1 page. use vmap */
2506 pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2507 if (!pages)
2508 return NULL;
2509
2510 /* convert sg[] to pages[] */
2511 for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2512 pages[i] = sg_page(sg);
2513 }
2514
2515 cmd->t_data_vmap = vmap(pages, cmd->t_data_nents, VM_MAP, PAGE_KERNEL);
2516 kfree(pages);
2517 if (!cmd->t_data_vmap)
2518 return NULL;
2519
2520 return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2521 }
2522 EXPORT_SYMBOL(transport_kmap_data_sg);
2523
2524 void transport_kunmap_data_sg(struct se_cmd *cmd)
2525 {
2526 if (!cmd->t_data_nents) {
2527 return;
2528 } else if (cmd->t_data_nents == 1) {
2529 kunmap(sg_page(cmd->t_data_sg));
2530 return;
2531 }
2532
2533 vunmap(cmd->t_data_vmap);
2534 cmd->t_data_vmap = NULL;
2535 }
2536 EXPORT_SYMBOL(transport_kunmap_data_sg);
2537
2538 int
2539 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2540 bool zero_page, bool chainable)
2541 {
2542 gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2543
2544 *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2545 return *sgl ? 0 : -ENOMEM;
2546 }
2547 EXPORT_SYMBOL(target_alloc_sgl);
2548
2549 /*
2550 * Allocate any required resources to execute the command. For writes we
2551 * might not have the payload yet, so notify the fabric via a call to
2552 * ->write_pending instead. Otherwise place it on the execution queue.
2553 */
2554 sense_reason_t
2555 transport_generic_new_cmd(struct se_cmd *cmd)
2556 {
2557 unsigned long flags;
2558 int ret = 0;
2559 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2560
2561 if (cmd->prot_op != TARGET_PROT_NORMAL &&
2562 !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2563 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2564 cmd->prot_length, true, false);
2565 if (ret < 0)
2566 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2567 }
2568
2569 /*
2570 * Determine if the TCM fabric module has already allocated physical
2571 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2572 * beforehand.
2573 */
2574 if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2575 cmd->data_length) {
2576
2577 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2578 (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2579 u32 bidi_length;
2580
2581 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2582 bidi_length = cmd->t_task_nolb *
2583 cmd->se_dev->dev_attrib.block_size;
2584 else
2585 bidi_length = cmd->data_length;
2586
2587 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2588 &cmd->t_bidi_data_nents,
2589 bidi_length, zero_flag, false);
2590 if (ret < 0)
2591 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2592 }
2593
2594 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2595 cmd->data_length, zero_flag, false);
2596 if (ret < 0)
2597 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2598 } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2599 cmd->data_length) {
2600 /*
2601 * Special case for COMPARE_AND_WRITE with fabrics
2602 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2603 */
2604 u32 caw_length = cmd->t_task_nolb *
2605 cmd->se_dev->dev_attrib.block_size;
2606
2607 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2608 &cmd->t_bidi_data_nents,
2609 caw_length, zero_flag, false);
2610 if (ret < 0)
2611 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2612 }
2613 /*
2614 * If this command is not a write we can execute it right here,
2615 * for write buffers we need to notify the fabric driver first
2616 * and let it call back once the write buffers are ready.
2617 */
2618 target_add_to_state_list(cmd);
2619 if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2620 target_execute_cmd(cmd);
2621 return 0;
2622 }
2623
2624 spin_lock_irqsave(&cmd->t_state_lock, flags);
2625 cmd->t_state = TRANSPORT_WRITE_PENDING;
2626 /*
2627 * Determine if frontend context caller is requesting the stopping of
2628 * this command for frontend exceptions.
2629 */
2630 if (cmd->transport_state & CMD_T_STOP &&
2631 !cmd->se_tfo->write_pending_must_be_called) {
2632 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2633 __func__, __LINE__, cmd->tag);
2634
2635 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2636
2637 complete_all(&cmd->t_transport_stop_comp);
2638 return 0;
2639 }
2640 cmd->transport_state &= ~CMD_T_ACTIVE;
2641 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2642
2643 ret = cmd->se_tfo->write_pending(cmd);
2644 if (ret)
2645 goto queue_full;
2646
2647 return 0;
2648
2649 queue_full:
2650 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2651 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2652 return 0;
2653 }
2654 EXPORT_SYMBOL(transport_generic_new_cmd);
2655
2656 static void transport_write_pending_qf(struct se_cmd *cmd)
2657 {
2658 unsigned long flags;
2659 int ret;
2660 bool stop;
2661
2662 spin_lock_irqsave(&cmd->t_state_lock, flags);
2663 stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2664 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2665
2666 if (stop) {
2667 pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2668 __func__, __LINE__, cmd->tag);
2669 complete_all(&cmd->t_transport_stop_comp);
2670 return;
2671 }
2672
2673 ret = cmd->se_tfo->write_pending(cmd);
2674 if (ret) {
2675 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2676 cmd);
2677 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2678 }
2679 }
2680
2681 static bool
2682 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2683 unsigned long *flags);
2684
2685 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2686 {
2687 unsigned long flags;
2688
2689 spin_lock_irqsave(&cmd->t_state_lock, flags);
2690 __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2691 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2692 }
2693
2694 /*
2695 * Call target_put_sess_cmd() and wait until target_release_cmd_kref(@cmd) has
2696 * finished.
2697 */
2698 void target_put_cmd_and_wait(struct se_cmd *cmd)
2699 {
2700 DECLARE_COMPLETION_ONSTACK(compl);
2701
2702 WARN_ON_ONCE(cmd->abrt_compl);
2703 cmd->abrt_compl = &compl;
2704 target_put_sess_cmd(cmd);
2705 wait_for_completion(&compl);
2706 }
2707
2708 /*
2709 * This function is called by frontend drivers after processing of a command
2710 * has finished.
2711 *
2712 * The protocol for ensuring that either the regular frontend command
2713 * processing flow or target_handle_abort() code drops one reference is as
2714 * follows:
2715 * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
2716 * the frontend driver to call this function synchronously or asynchronously.
2717 * That will cause one reference to be dropped.
2718 * - During regular command processing the target core sets CMD_T_COMPLETE
2719 * before invoking one of the .queue_*() functions.
2720 * - The code that aborts commands skips commands and TMFs for which
2721 * CMD_T_COMPLETE has been set.
2722 * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
2723 * commands that will be aborted.
2724 * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
2725 * transport_generic_free_cmd() skips its call to target_put_sess_cmd().
2726 * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
2727 * be called and will drop a reference.
2728 * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
2729 * will be called. target_handle_abort() will drop the final reference.
2730 */
2731 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2732 {
2733 DECLARE_COMPLETION_ONSTACK(compl);
2734 int ret = 0;
2735 bool aborted = false, tas = false;
2736
2737 if (wait_for_tasks)
2738 target_wait_free_cmd(cmd, &aborted, &tas);
2739
2740 if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
2741 /*
2742 * Handle WRITE failure case where transport_generic_new_cmd()
2743 * has already added se_cmd to state_list, but fabric has
2744 * failed command before I/O submission.
2745 */
2746 if (cmd->state_active)
2747 target_remove_from_state_list(cmd);
2748
2749 if (cmd->se_lun)
2750 transport_lun_remove_cmd(cmd);
2751 }
2752 if (aborted)
2753 cmd->free_compl = &compl;
2754 ret = target_put_sess_cmd(cmd);
2755 if (aborted) {
2756 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2757 wait_for_completion(&compl);
2758 ret = 1;
2759 }
2760 return ret;
2761 }
2762 EXPORT_SYMBOL(transport_generic_free_cmd);
2763
2764 /**
2765 * target_get_sess_cmd - Verify the session is accepting cmds and take ref
2766 * @se_cmd: command descriptor to add
2767 * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd()
2768 */
2769 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2770 {
2771 struct se_session *se_sess = se_cmd->se_sess;
2772 int ret = 0;
2773
2774 /*
2775 * Add a second kref if the fabric caller is expecting to handle
2776 * fabric acknowledgement that requires two target_put_sess_cmd()
2777 * invocations before se_cmd descriptor release.
2778 */
2779 if (ack_kref) {
2780 if (!kref_get_unless_zero(&se_cmd->cmd_kref))
2781 return -EINVAL;
2782
2783 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2784 }
2785
2786 if (!percpu_ref_tryget_live(&se_sess->cmd_count))
2787 ret = -ESHUTDOWN;
2788
2789 if (ret && ack_kref)
2790 target_put_sess_cmd(se_cmd);
2791
2792 return ret;
2793 }
2794 EXPORT_SYMBOL(target_get_sess_cmd);
2795
2796 static void target_free_cmd_mem(struct se_cmd *cmd)
2797 {
2798 transport_free_pages(cmd);
2799
2800 if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2801 core_tmr_release_req(cmd->se_tmr_req);
2802 if (cmd->t_task_cdb != cmd->__t_task_cdb)
2803 kfree(cmd->t_task_cdb);
2804 }
2805
2806 static void target_release_cmd_kref(struct kref *kref)
2807 {
2808 struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2809 struct se_session *se_sess = se_cmd->se_sess;
2810 struct completion *free_compl = se_cmd->free_compl;
2811 struct completion *abrt_compl = se_cmd->abrt_compl;
2812
2813 target_free_cmd_mem(se_cmd);
2814 se_cmd->se_tfo->release_cmd(se_cmd);
2815 if (free_compl)
2816 complete(free_compl);
2817 if (abrt_compl)
2818 complete(abrt_compl);
2819
2820 percpu_ref_put(&se_sess->cmd_count);
2821 }
2822
2823 /**
2824 * target_put_sess_cmd - decrease the command reference count
2825 * @se_cmd: command to drop a reference from
2826 *
2827 * Returns 1 if and only if this target_put_sess_cmd() call caused the
2828 * refcount to drop to zero. Returns zero otherwise.
2829 */
2830 int target_put_sess_cmd(struct se_cmd *se_cmd)
2831 {
2832 return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2833 }
2834 EXPORT_SYMBOL(target_put_sess_cmd);
2835
2836 static const char *data_dir_name(enum dma_data_direction d)
2837 {
2838 switch (d) {
2839 case DMA_BIDIRECTIONAL: return "BIDI";
2840 case DMA_TO_DEVICE: return "WRITE";
2841 case DMA_FROM_DEVICE: return "READ";
2842 case DMA_NONE: return "NONE";
2843 }
2844
2845 return "(?)";
2846 }
2847
2848 static const char *cmd_state_name(enum transport_state_table t)
2849 {
2850 switch (t) {
2851 case TRANSPORT_NO_STATE: return "NO_STATE";
2852 case TRANSPORT_NEW_CMD: return "NEW_CMD";
2853 case TRANSPORT_WRITE_PENDING: return "WRITE_PENDING";
2854 case TRANSPORT_PROCESSING: return "PROCESSING";
2855 case TRANSPORT_COMPLETE: return "COMPLETE";
2856 case TRANSPORT_ISTATE_PROCESSING:
2857 return "ISTATE_PROCESSING";
2858 case TRANSPORT_COMPLETE_QF_WP: return "COMPLETE_QF_WP";
2859 case TRANSPORT_COMPLETE_QF_OK: return "COMPLETE_QF_OK";
2860 case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR";
2861 }
2862
2863 return "(?)";
2864 }
2865
2866 static void target_append_str(char **str, const char *txt)
2867 {
2868 char *prev = *str;
2869
2870 *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
2871 kstrdup(txt, GFP_ATOMIC);
2872 kfree(prev);
2873 }
2874
2875 /*
2876 * Convert a transport state bitmask into a string. The caller is
2877 * responsible for freeing the returned pointer.
2878 */
2879 static char *target_ts_to_str(u32 ts)
2880 {
2881 char *str = NULL;
2882
2883 if (ts & CMD_T_ABORTED)
2884 target_append_str(&str, "aborted");
2885 if (ts & CMD_T_ACTIVE)
2886 target_append_str(&str, "active");
2887 if (ts & CMD_T_COMPLETE)
2888 target_append_str(&str, "complete");
2889 if (ts & CMD_T_SENT)
2890 target_append_str(&str, "sent");
2891 if (ts & CMD_T_STOP)
2892 target_append_str(&str, "stop");
2893 if (ts & CMD_T_FABRIC_STOP)
2894 target_append_str(&str, "fabric_stop");
2895
2896 return str;
2897 }
2898
2899 static const char *target_tmf_name(enum tcm_tmreq_table tmf)
2900 {
2901 switch (tmf) {
2902 case TMR_ABORT_TASK: return "ABORT_TASK";
2903 case TMR_ABORT_TASK_SET: return "ABORT_TASK_SET";
2904 case TMR_CLEAR_ACA: return "CLEAR_ACA";
2905 case TMR_CLEAR_TASK_SET: return "CLEAR_TASK_SET";
2906 case TMR_LUN_RESET: return "LUN_RESET";
2907 case TMR_TARGET_WARM_RESET: return "TARGET_WARM_RESET";
2908 case TMR_TARGET_COLD_RESET: return "TARGET_COLD_RESET";
2909 case TMR_LUN_RESET_PRO: return "LUN_RESET_PRO";
2910 case TMR_UNKNOWN: break;
2911 }
2912 return "(?)";
2913 }
2914
2915 void target_show_cmd(const char *pfx, struct se_cmd *cmd)
2916 {
2917 char *ts_str = target_ts_to_str(cmd->transport_state);
2918 const u8 *cdb = cmd->t_task_cdb;
2919 struct se_tmr_req *tmf = cmd->se_tmr_req;
2920
2921 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2922 pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
2923 pfx, cdb[0], cdb[1], cmd->tag,
2924 data_dir_name(cmd->data_direction),
2925 cmd->se_tfo->get_cmd_state(cmd),
2926 cmd_state_name(cmd->t_state), cmd->data_length,
2927 kref_read(&cmd->cmd_kref), ts_str);
2928 } else {
2929 pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
2930 pfx, target_tmf_name(tmf->function), cmd->tag,
2931 tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
2932 cmd_state_name(cmd->t_state),
2933 kref_read(&cmd->cmd_kref), ts_str);
2934 }
2935 kfree(ts_str);
2936 }
2937 EXPORT_SYMBOL(target_show_cmd);
2938
2939 static void target_stop_session_confirm(struct percpu_ref *ref)
2940 {
2941 struct se_session *se_sess = container_of(ref, struct se_session,
2942 cmd_count);
2943 complete_all(&se_sess->stop_done);
2944 }
2945
2946 /**
2947 * target_stop_session - Stop new IO from being queued on the session.
2948 * @se_sess: session to stop
2949 */
2950 void target_stop_session(struct se_session *se_sess)
2951 {
2952 pr_debug("Stopping session queue.\n");
2953 if (atomic_cmpxchg(&se_sess->stopped, 0, 1) == 0)
2954 percpu_ref_kill_and_confirm(&se_sess->cmd_count,
2955 target_stop_session_confirm);
2956 }
2957 EXPORT_SYMBOL(target_stop_session);
2958
2959 /**
2960 * target_wait_for_sess_cmds - Wait for outstanding commands
2961 * @se_sess: session to wait for active I/O
2962 */
2963 void target_wait_for_sess_cmds(struct se_session *se_sess)
2964 {
2965 int ret;
2966
2967 WARN_ON_ONCE(!atomic_read(&se_sess->stopped));
2968
2969 do {
2970 pr_debug("Waiting for running cmds to complete.\n");
2971 ret = wait_event_timeout(se_sess->cmd_count_wq,
2972 percpu_ref_is_zero(&se_sess->cmd_count),
2973 180 * HZ);
2974 } while (ret <= 0);
2975
2976 wait_for_completion(&se_sess->stop_done);
2977 pr_debug("Waiting for cmds done.\n");
2978 }
2979 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2980
2981 /*
2982 * Prevent that new percpu_ref_tryget_live() calls succeed and wait until
2983 * all references to the LUN have been released. Called during LUN shutdown.
2984 */
2985 void transport_clear_lun_ref(struct se_lun *lun)
2986 {
2987 percpu_ref_kill(&lun->lun_ref);
2988 wait_for_completion(&lun->lun_shutdown_comp);
2989 }
2990
2991 static bool
2992 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2993 bool *aborted, bool *tas, unsigned long *flags)
2994 __releases(&cmd->t_state_lock)
2995 __acquires(&cmd->t_state_lock)
2996 {
2997
2998 assert_spin_locked(&cmd->t_state_lock);
2999 WARN_ON_ONCE(!irqs_disabled());
3000
3001 if (fabric_stop)
3002 cmd->transport_state |= CMD_T_FABRIC_STOP;
3003
3004 if (cmd->transport_state & CMD_T_ABORTED)
3005 *aborted = true;
3006
3007 if (cmd->transport_state & CMD_T_TAS)
3008 *tas = true;
3009
3010 if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
3011 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3012 return false;
3013
3014 if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
3015 !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3016 return false;
3017
3018 if (!(cmd->transport_state & CMD_T_ACTIVE))
3019 return false;
3020
3021 if (fabric_stop && *aborted)
3022 return false;
3023
3024 cmd->transport_state |= CMD_T_STOP;
3025
3026 target_show_cmd("wait_for_tasks: Stopping ", cmd);
3027
3028 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
3029
3030 while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
3031 180 * HZ))
3032 target_show_cmd("wait for tasks: ", cmd);
3033
3034 spin_lock_irqsave(&cmd->t_state_lock, *flags);
3035 cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
3036
3037 pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
3038 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
3039
3040 return true;
3041 }
3042
3043 /**
3044 * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
3045 * @cmd: command to wait on
3046 */
3047 bool transport_wait_for_tasks(struct se_cmd *cmd)
3048 {
3049 unsigned long flags;
3050 bool ret, aborted = false, tas = false;
3051
3052 spin_lock_irqsave(&cmd->t_state_lock, flags);
3053 ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
3054 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3055
3056 return ret;
3057 }
3058 EXPORT_SYMBOL(transport_wait_for_tasks);
3059
3060 struct sense_detail {
3061 u8 key;
3062 u8 asc;
3063 u8 ascq;
3064 bool add_sense_info;
3065 };
3066
3067 static const struct sense_detail sense_detail_table[] = {
3068 [TCM_NO_SENSE] = {
3069 .key = NOT_READY
3070 },
3071 [TCM_NON_EXISTENT_LUN] = {
3072 .key = ILLEGAL_REQUEST,
3073 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
3074 },
3075 [TCM_UNSUPPORTED_SCSI_OPCODE] = {
3076 .key = ILLEGAL_REQUEST,
3077 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3078 },
3079 [TCM_SECTOR_COUNT_TOO_MANY] = {
3080 .key = ILLEGAL_REQUEST,
3081 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3082 },
3083 [TCM_UNKNOWN_MODE_PAGE] = {
3084 .key = ILLEGAL_REQUEST,
3085 .asc = 0x24, /* INVALID FIELD IN CDB */
3086 },
3087 [TCM_CHECK_CONDITION_ABORT_CMD] = {
3088 .key = ABORTED_COMMAND,
3089 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3090 .ascq = 0x03,
3091 },
3092 [TCM_INCORRECT_AMOUNT_OF_DATA] = {
3093 .key = ABORTED_COMMAND,
3094 .asc = 0x0c, /* WRITE ERROR */
3095 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3096 },
3097 [TCM_INVALID_CDB_FIELD] = {
3098 .key = ILLEGAL_REQUEST,
3099 .asc = 0x24, /* INVALID FIELD IN CDB */
3100 },
3101 [TCM_INVALID_PARAMETER_LIST] = {
3102 .key = ILLEGAL_REQUEST,
3103 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3104 },
3105 [TCM_TOO_MANY_TARGET_DESCS] = {
3106 .key = ILLEGAL_REQUEST,
3107 .asc = 0x26,
3108 .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3109 },
3110 [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3111 .key = ILLEGAL_REQUEST,
3112 .asc = 0x26,
3113 .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3114 },
3115 [TCM_TOO_MANY_SEGMENT_DESCS] = {
3116 .key = ILLEGAL_REQUEST,
3117 .asc = 0x26,
3118 .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3119 },
3120 [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3121 .key = ILLEGAL_REQUEST,
3122 .asc = 0x26,
3123 .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3124 },
3125 [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3126 .key = ILLEGAL_REQUEST,
3127 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3128 },
3129 [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3130 .key = ILLEGAL_REQUEST,
3131 .asc = 0x0c, /* WRITE ERROR */
3132 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3133 },
3134 [TCM_SERVICE_CRC_ERROR] = {
3135 .key = ABORTED_COMMAND,
3136 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3137 .ascq = 0x05, /* N/A */
3138 },
3139 [TCM_SNACK_REJECTED] = {
3140 .key = ABORTED_COMMAND,
3141 .asc = 0x11, /* READ ERROR */
3142 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3143 },
3144 [TCM_WRITE_PROTECTED] = {
3145 .key = DATA_PROTECT,
3146 .asc = 0x27, /* WRITE PROTECTED */
3147 },
3148 [TCM_ADDRESS_OUT_OF_RANGE] = {
3149 .key = ILLEGAL_REQUEST,
3150 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3151 },
3152 [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3153 .key = UNIT_ATTENTION,
3154 },
3155 [TCM_CHECK_CONDITION_NOT_READY] = {
3156 .key = NOT_READY,
3157 },
3158 [TCM_MISCOMPARE_VERIFY] = {
3159 .key = MISCOMPARE,
3160 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3161 .ascq = 0x00,
3162 .add_sense_info = true,
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_sense_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_sense_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_sense_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_detail *sd;
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_detail_table) && sense_detail_table[r].key)
3235 sd = &sense_detail_table[r];
3236 else
3237 sd = &sense_detail_table[(__force int)
3238 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3239
3240 key = sd->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 (sd->asc == 0) {
3248 WARN_ON_ONCE(cmd->scsi_asc == 0);
3249 asc = cmd->scsi_asc;
3250 ascq = cmd->scsi_ascq;
3251 } else {
3252 asc = sd->asc;
3253 ascq = sd->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 (sd->add_sense_info)
3261 WARN_ON_ONCE(scsi_set_sense_information(buffer,
3262 cmd->scsi_sense_length,
3263 cmd->sense_info) < 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 }
Linux with added FPC-III support