Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target...
[muen/linux.git] / drivers / target / target_core_transport.c
1 /*******************************************************************************
2  * Filename:  target_core_transport.c
3  *
4  * This file contains the Generic Target Engine Core.
5  *
6  * (c) Copyright 2002-2013 Datera, Inc.
7  *
8  * Nicholas A. Bellinger <nab@kernel.org>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23  *
24  ******************************************************************************/
25
26 #include <linux/net.h>
27 #include <linux/delay.h>
28 #include <linux/string.h>
29 #include <linux/timer.h>
30 #include <linux/slab.h>
31 #include <linux/spinlock.h>
32 #include <linux/kthread.h>
33 #include <linux/in.h>
34 #include <linux/cdrom.h>
35 #include <linux/module.h>
36 #include <linux/ratelimit.h>
37 #include <linux/vmalloc.h>
38 #include <asm/unaligned.h>
39 #include <net/sock.h>
40 #include <net/tcp.h>
41 #include <scsi/scsi_proto.h>
42 #include <scsi/scsi_common.h>
43
44 #include <target/target_core_base.h>
45 #include <target/target_core_backend.h>
46 #include <target/target_core_fabric.h>
47
48 #include "target_core_internal.h"
49 #include "target_core_alua.h"
50 #include "target_core_pr.h"
51 #include "target_core_ua.h"
52
53 #define CREATE_TRACE_POINTS
54 #include <trace/events/target.h>
55
56 static struct workqueue_struct *target_completion_wq;
57 static struct kmem_cache *se_sess_cache;
58 struct kmem_cache *se_ua_cache;
59 struct kmem_cache *t10_pr_reg_cache;
60 struct kmem_cache *t10_alua_lu_gp_cache;
61 struct kmem_cache *t10_alua_lu_gp_mem_cache;
62 struct kmem_cache *t10_alua_tg_pt_gp_cache;
63 struct kmem_cache *t10_alua_lba_map_cache;
64 struct kmem_cache *t10_alua_lba_map_mem_cache;
65
66 static void transport_complete_task_attr(struct se_cmd *cmd);
67 static int translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason);
68 static void transport_handle_queue_full(struct se_cmd *cmd,
69                 struct se_device *dev, int err, bool write_pending);
70 static void target_complete_ok_work(struct work_struct *work);
71
72 int init_se_kmem_caches(void)
73 {
74         se_sess_cache = kmem_cache_create("se_sess_cache",
75                         sizeof(struct se_session), __alignof__(struct se_session),
76                         0, NULL);
77         if (!se_sess_cache) {
78                 pr_err("kmem_cache_create() for struct se_session"
79                                 " failed\n");
80                 goto out;
81         }
82         se_ua_cache = kmem_cache_create("se_ua_cache",
83                         sizeof(struct se_ua), __alignof__(struct se_ua),
84                         0, NULL);
85         if (!se_ua_cache) {
86                 pr_err("kmem_cache_create() for struct se_ua failed\n");
87                 goto out_free_sess_cache;
88         }
89         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
90                         sizeof(struct t10_pr_registration),
91                         __alignof__(struct t10_pr_registration), 0, NULL);
92         if (!t10_pr_reg_cache) {
93                 pr_err("kmem_cache_create() for struct t10_pr_registration"
94                                 " failed\n");
95                 goto out_free_ua_cache;
96         }
97         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
98                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
99                         0, NULL);
100         if (!t10_alua_lu_gp_cache) {
101                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
102                                 " failed\n");
103                 goto out_free_pr_reg_cache;
104         }
105         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
106                         sizeof(struct t10_alua_lu_gp_member),
107                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
108         if (!t10_alua_lu_gp_mem_cache) {
109                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
110                                 "cache failed\n");
111                 goto out_free_lu_gp_cache;
112         }
113         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
114                         sizeof(struct t10_alua_tg_pt_gp),
115                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
116         if (!t10_alua_tg_pt_gp_cache) {
117                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
118                                 "cache failed\n");
119                 goto out_free_lu_gp_mem_cache;
120         }
121         t10_alua_lba_map_cache = kmem_cache_create(
122                         "t10_alua_lba_map_cache",
123                         sizeof(struct t10_alua_lba_map),
124                         __alignof__(struct t10_alua_lba_map), 0, NULL);
125         if (!t10_alua_lba_map_cache) {
126                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
127                                 "cache failed\n");
128                 goto out_free_tg_pt_gp_cache;
129         }
130         t10_alua_lba_map_mem_cache = kmem_cache_create(
131                         "t10_alua_lba_map_mem_cache",
132                         sizeof(struct t10_alua_lba_map_member),
133                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
134         if (!t10_alua_lba_map_mem_cache) {
135                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
136                                 "cache failed\n");
137                 goto out_free_lba_map_cache;
138         }
139
140         target_completion_wq = alloc_workqueue("target_completion",
141                                                WQ_MEM_RECLAIM, 0);
142         if (!target_completion_wq)
143                 goto out_free_lba_map_mem_cache;
144
145         return 0;
146
147 out_free_lba_map_mem_cache:
148         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
149 out_free_lba_map_cache:
150         kmem_cache_destroy(t10_alua_lba_map_cache);
151 out_free_tg_pt_gp_cache:
152         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
153 out_free_lu_gp_mem_cache:
154         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
155 out_free_lu_gp_cache:
156         kmem_cache_destroy(t10_alua_lu_gp_cache);
157 out_free_pr_reg_cache:
158         kmem_cache_destroy(t10_pr_reg_cache);
159 out_free_ua_cache:
160         kmem_cache_destroy(se_ua_cache);
161 out_free_sess_cache:
162         kmem_cache_destroy(se_sess_cache);
163 out:
164         return -ENOMEM;
165 }
166
167 void release_se_kmem_caches(void)
168 {
169         destroy_workqueue(target_completion_wq);
170         kmem_cache_destroy(se_sess_cache);
171         kmem_cache_destroy(se_ua_cache);
172         kmem_cache_destroy(t10_pr_reg_cache);
173         kmem_cache_destroy(t10_alua_lu_gp_cache);
174         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
175         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
176         kmem_cache_destroy(t10_alua_lba_map_cache);
177         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
178 }
179
180 /* This code ensures unique mib indexes are handed out. */
181 static DEFINE_SPINLOCK(scsi_mib_index_lock);
182 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
183
184 /*
185  * Allocate a new row index for the entry type specified
186  */
187 u32 scsi_get_new_index(scsi_index_t type)
188 {
189         u32 new_index;
190
191         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
192
193         spin_lock(&scsi_mib_index_lock);
194         new_index = ++scsi_mib_index[type];
195         spin_unlock(&scsi_mib_index_lock);
196
197         return new_index;
198 }
199
200 void transport_subsystem_check_init(void)
201 {
202         int ret;
203         static int sub_api_initialized;
204
205         if (sub_api_initialized)
206                 return;
207
208         ret = request_module("target_core_iblock");
209         if (ret != 0)
210                 pr_err("Unable to load target_core_iblock\n");
211
212         ret = request_module("target_core_file");
213         if (ret != 0)
214                 pr_err("Unable to load target_core_file\n");
215
216         ret = request_module("target_core_pscsi");
217         if (ret != 0)
218                 pr_err("Unable to load target_core_pscsi\n");
219
220         ret = request_module("target_core_user");
221         if (ret != 0)
222                 pr_err("Unable to load target_core_user\n");
223
224         sub_api_initialized = 1;
225 }
226
227 struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
228 {
229         struct se_session *se_sess;
230
231         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
232         if (!se_sess) {
233                 pr_err("Unable to allocate struct se_session from"
234                                 " se_sess_cache\n");
235                 return ERR_PTR(-ENOMEM);
236         }
237         INIT_LIST_HEAD(&se_sess->sess_list);
238         INIT_LIST_HEAD(&se_sess->sess_acl_list);
239         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
240         INIT_LIST_HEAD(&se_sess->sess_wait_list);
241         spin_lock_init(&se_sess->sess_cmd_lock);
242         se_sess->sup_prot_ops = sup_prot_ops;
243
244         return se_sess;
245 }
246 EXPORT_SYMBOL(transport_init_session);
247
248 int transport_alloc_session_tags(struct se_session *se_sess,
249                                  unsigned int tag_num, unsigned int tag_size)
250 {
251         int rc;
252
253         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
254                                         GFP_KERNEL | __GFP_NOWARN | __GFP_RETRY_MAYFAIL);
255         if (!se_sess->sess_cmd_map) {
256                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
257                 if (!se_sess->sess_cmd_map) {
258                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
259                         return -ENOMEM;
260                 }
261         }
262
263         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
264         if (rc < 0) {
265                 pr_err("Unable to init se_sess->sess_tag_pool,"
266                         " tag_num: %u\n", tag_num);
267                 kvfree(se_sess->sess_cmd_map);
268                 se_sess->sess_cmd_map = NULL;
269                 return -ENOMEM;
270         }
271
272         return 0;
273 }
274 EXPORT_SYMBOL(transport_alloc_session_tags);
275
276 struct se_session *transport_init_session_tags(unsigned int tag_num,
277                                                unsigned int tag_size,
278                                                enum target_prot_op sup_prot_ops)
279 {
280         struct se_session *se_sess;
281         int rc;
282
283         if (tag_num != 0 && !tag_size) {
284                 pr_err("init_session_tags called with percpu-ida tag_num:"
285                        " %u, but zero tag_size\n", tag_num);
286                 return ERR_PTR(-EINVAL);
287         }
288         if (!tag_num && tag_size) {
289                 pr_err("init_session_tags called with percpu-ida tag_size:"
290                        " %u, but zero tag_num\n", tag_size);
291                 return ERR_PTR(-EINVAL);
292         }
293
294         se_sess = transport_init_session(sup_prot_ops);
295         if (IS_ERR(se_sess))
296                 return se_sess;
297
298         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
299         if (rc < 0) {
300                 transport_free_session(se_sess);
301                 return ERR_PTR(-ENOMEM);
302         }
303
304         return se_sess;
305 }
306 EXPORT_SYMBOL(transport_init_session_tags);
307
308 /*
309  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
310  */
311 void __transport_register_session(
312         struct se_portal_group *se_tpg,
313         struct se_node_acl *se_nacl,
314         struct se_session *se_sess,
315         void *fabric_sess_ptr)
316 {
317         const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
318         unsigned char buf[PR_REG_ISID_LEN];
319
320         se_sess->se_tpg = se_tpg;
321         se_sess->fabric_sess_ptr = fabric_sess_ptr;
322         /*
323          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
324          *
325          * Only set for struct se_session's that will actually be moving I/O.
326          * eg: *NOT* discovery sessions.
327          */
328         if (se_nacl) {
329                 /*
330                  *
331                  * Determine if fabric allows for T10-PI feature bits exposed to
332                  * initiators for device backends with !dev->dev_attrib.pi_prot_type.
333                  *
334                  * If so, then always save prot_type on a per se_node_acl node
335                  * basis and re-instate the previous sess_prot_type to avoid
336                  * disabling PI from below any previously initiator side
337                  * registered LUNs.
338                  */
339                 if (se_nacl->saved_prot_type)
340                         se_sess->sess_prot_type = se_nacl->saved_prot_type;
341                 else if (tfo->tpg_check_prot_fabric_only)
342                         se_sess->sess_prot_type = se_nacl->saved_prot_type =
343                                         tfo->tpg_check_prot_fabric_only(se_tpg);
344                 /*
345                  * If the fabric module supports an ISID based TransportID,
346                  * save this value in binary from the fabric I_T Nexus now.
347                  */
348                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
349                         memset(&buf[0], 0, PR_REG_ISID_LEN);
350                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
351                                         &buf[0], PR_REG_ISID_LEN);
352                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
353                 }
354
355                 spin_lock_irq(&se_nacl->nacl_sess_lock);
356                 /*
357                  * The se_nacl->nacl_sess pointer will be set to the
358                  * last active I_T Nexus for each struct se_node_acl.
359                  */
360                 se_nacl->nacl_sess = se_sess;
361
362                 list_add_tail(&se_sess->sess_acl_list,
363                               &se_nacl->acl_sess_list);
364                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
365         }
366         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
367
368         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
369                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
370 }
371 EXPORT_SYMBOL(__transport_register_session);
372
373 void transport_register_session(
374         struct se_portal_group *se_tpg,
375         struct se_node_acl *se_nacl,
376         struct se_session *se_sess,
377         void *fabric_sess_ptr)
378 {
379         unsigned long flags;
380
381         spin_lock_irqsave(&se_tpg->session_lock, flags);
382         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
383         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
384 }
385 EXPORT_SYMBOL(transport_register_session);
386
387 struct se_session *
388 target_alloc_session(struct se_portal_group *tpg,
389                      unsigned int tag_num, unsigned int tag_size,
390                      enum target_prot_op prot_op,
391                      const char *initiatorname, void *private,
392                      int (*callback)(struct se_portal_group *,
393                                      struct se_session *, void *))
394 {
395         struct se_session *sess;
396
397         /*
398          * If the fabric driver is using percpu-ida based pre allocation
399          * of I/O descriptor tags, go ahead and perform that setup now..
400          */
401         if (tag_num != 0)
402                 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
403         else
404                 sess = transport_init_session(prot_op);
405
406         if (IS_ERR(sess))
407                 return sess;
408
409         sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
410                                         (unsigned char *)initiatorname);
411         if (!sess->se_node_acl) {
412                 transport_free_session(sess);
413                 return ERR_PTR(-EACCES);
414         }
415         /*
416          * Go ahead and perform any remaining fabric setup that is
417          * required before transport_register_session().
418          */
419         if (callback != NULL) {
420                 int rc = callback(tpg, sess, private);
421                 if (rc) {
422                         transport_free_session(sess);
423                         return ERR_PTR(rc);
424                 }
425         }
426
427         transport_register_session(tpg, sess->se_node_acl, sess, private);
428         return sess;
429 }
430 EXPORT_SYMBOL(target_alloc_session);
431
432 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
433 {
434         struct se_session *se_sess;
435         ssize_t len = 0;
436
437         spin_lock_bh(&se_tpg->session_lock);
438         list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
439                 if (!se_sess->se_node_acl)
440                         continue;
441                 if (!se_sess->se_node_acl->dynamic_node_acl)
442                         continue;
443                 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
444                         break;
445
446                 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
447                                 se_sess->se_node_acl->initiatorname);
448                 len += 1; /* Include NULL terminator */
449         }
450         spin_unlock_bh(&se_tpg->session_lock);
451
452         return len;
453 }
454 EXPORT_SYMBOL(target_show_dynamic_sessions);
455
456 static void target_complete_nacl(struct kref *kref)
457 {
458         struct se_node_acl *nacl = container_of(kref,
459                                 struct se_node_acl, acl_kref);
460         struct se_portal_group *se_tpg = nacl->se_tpg;
461
462         if (!nacl->dynamic_stop) {
463                 complete(&nacl->acl_free_comp);
464                 return;
465         }
466
467         mutex_lock(&se_tpg->acl_node_mutex);
468         list_del_init(&nacl->acl_list);
469         mutex_unlock(&se_tpg->acl_node_mutex);
470
471         core_tpg_wait_for_nacl_pr_ref(nacl);
472         core_free_device_list_for_node(nacl, se_tpg);
473         kfree(nacl);
474 }
475
476 void target_put_nacl(struct se_node_acl *nacl)
477 {
478         kref_put(&nacl->acl_kref, target_complete_nacl);
479 }
480 EXPORT_SYMBOL(target_put_nacl);
481
482 void transport_deregister_session_configfs(struct se_session *se_sess)
483 {
484         struct se_node_acl *se_nacl;
485         unsigned long flags;
486         /*
487          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
488          */
489         se_nacl = se_sess->se_node_acl;
490         if (se_nacl) {
491                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
492                 if (!list_empty(&se_sess->sess_acl_list))
493                         list_del_init(&se_sess->sess_acl_list);
494                 /*
495                  * If the session list is empty, then clear the pointer.
496                  * Otherwise, set the struct se_session pointer from the tail
497                  * element of the per struct se_node_acl active session list.
498                  */
499                 if (list_empty(&se_nacl->acl_sess_list))
500                         se_nacl->nacl_sess = NULL;
501                 else {
502                         se_nacl->nacl_sess = container_of(
503                                         se_nacl->acl_sess_list.prev,
504                                         struct se_session, sess_acl_list);
505                 }
506                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
507         }
508 }
509 EXPORT_SYMBOL(transport_deregister_session_configfs);
510
511 void transport_free_session(struct se_session *se_sess)
512 {
513         struct se_node_acl *se_nacl = se_sess->se_node_acl;
514
515         /*
516          * Drop the se_node_acl->nacl_kref obtained from within
517          * core_tpg_get_initiator_node_acl().
518          */
519         if (se_nacl) {
520                 struct se_portal_group *se_tpg = se_nacl->se_tpg;
521                 const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
522                 unsigned long flags;
523
524                 se_sess->se_node_acl = NULL;
525
526                 /*
527                  * Also determine if we need to drop the extra ->cmd_kref if
528                  * it had been previously dynamically generated, and
529                  * the endpoint is not caching dynamic ACLs.
530                  */
531                 mutex_lock(&se_tpg->acl_node_mutex);
532                 if (se_nacl->dynamic_node_acl &&
533                     !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
534                         spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
535                         if (list_empty(&se_nacl->acl_sess_list))
536                                 se_nacl->dynamic_stop = true;
537                         spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
538
539                         if (se_nacl->dynamic_stop)
540                                 list_del_init(&se_nacl->acl_list);
541                 }
542                 mutex_unlock(&se_tpg->acl_node_mutex);
543
544                 if (se_nacl->dynamic_stop)
545                         target_put_nacl(se_nacl);
546
547                 target_put_nacl(se_nacl);
548         }
549         if (se_sess->sess_cmd_map) {
550                 percpu_ida_destroy(&se_sess->sess_tag_pool);
551                 kvfree(se_sess->sess_cmd_map);
552         }
553         kmem_cache_free(se_sess_cache, se_sess);
554 }
555 EXPORT_SYMBOL(transport_free_session);
556
557 void transport_deregister_session(struct se_session *se_sess)
558 {
559         struct se_portal_group *se_tpg = se_sess->se_tpg;
560         unsigned long flags;
561
562         if (!se_tpg) {
563                 transport_free_session(se_sess);
564                 return;
565         }
566
567         spin_lock_irqsave(&se_tpg->session_lock, flags);
568         list_del(&se_sess->sess_list);
569         se_sess->se_tpg = NULL;
570         se_sess->fabric_sess_ptr = NULL;
571         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
572
573         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
574                 se_tpg->se_tpg_tfo->get_fabric_name());
575         /*
576          * If last kref is dropping now for an explicit NodeACL, awake sleeping
577          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
578          * removal context from within transport_free_session() code.
579          *
580          * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
581          * to release all remaining generate_node_acl=1 created ACL resources.
582          */
583
584         transport_free_session(se_sess);
585 }
586 EXPORT_SYMBOL(transport_deregister_session);
587
588 static void target_remove_from_state_list(struct se_cmd *cmd)
589 {
590         struct se_device *dev = cmd->se_dev;
591         unsigned long flags;
592
593         if (!dev)
594                 return;
595
596         spin_lock_irqsave(&dev->execute_task_lock, flags);
597         if (cmd->state_active) {
598                 list_del(&cmd->state_list);
599                 cmd->state_active = false;
600         }
601         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
602 }
603
604 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
605 {
606         unsigned long flags;
607
608         target_remove_from_state_list(cmd);
609
610         /*
611          * Clear struct se_cmd->se_lun before the handoff to FE.
612          */
613         cmd->se_lun = NULL;
614
615         spin_lock_irqsave(&cmd->t_state_lock, flags);
616         /*
617          * Determine if frontend context caller is requesting the stopping of
618          * this command for frontend exceptions.
619          */
620         if (cmd->transport_state & CMD_T_STOP) {
621                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
622                         __func__, __LINE__, cmd->tag);
623
624                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
625
626                 complete_all(&cmd->t_transport_stop_comp);
627                 return 1;
628         }
629         cmd->transport_state &= ~CMD_T_ACTIVE;
630         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
631
632         /*
633          * Some fabric modules like tcm_loop can release their internally
634          * allocated I/O reference and struct se_cmd now.
635          *
636          * Fabric modules are expected to return '1' here if the se_cmd being
637          * passed is released at this point, or zero if not being released.
638          */
639         return cmd->se_tfo->check_stop_free(cmd);
640 }
641
642 static void transport_lun_remove_cmd(struct se_cmd *cmd)
643 {
644         struct se_lun *lun = cmd->se_lun;
645
646         if (!lun)
647                 return;
648
649         if (cmpxchg(&cmd->lun_ref_active, true, false))
650                 percpu_ref_put(&lun->lun_ref);
651 }
652
653 int transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
654 {
655         bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF);
656         int ret = 0;
657
658         if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
659                 transport_lun_remove_cmd(cmd);
660         /*
661          * Allow the fabric driver to unmap any resources before
662          * releasing the descriptor via TFO->release_cmd()
663          */
664         if (remove)
665                 cmd->se_tfo->aborted_task(cmd);
666
667         if (transport_cmd_check_stop_to_fabric(cmd))
668                 return 1;
669         if (remove && ack_kref)
670                 ret = target_put_sess_cmd(cmd);
671
672         return ret;
673 }
674
675 static void target_complete_failure_work(struct work_struct *work)
676 {
677         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
678
679         transport_generic_request_failure(cmd,
680                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
681 }
682
683 /*
684  * Used when asking transport to copy Sense Data from the underlying
685  * Linux/SCSI struct scsi_cmnd
686  */
687 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
688 {
689         struct se_device *dev = cmd->se_dev;
690
691         WARN_ON(!cmd->se_lun);
692
693         if (!dev)
694                 return NULL;
695
696         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
697                 return NULL;
698
699         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
700
701         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
702                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
703         return cmd->sense_buffer;
704 }
705
706 void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
707 {
708         unsigned char *cmd_sense_buf;
709         unsigned long flags;
710
711         spin_lock_irqsave(&cmd->t_state_lock, flags);
712         cmd_sense_buf = transport_get_sense_buffer(cmd);
713         if (!cmd_sense_buf) {
714                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
715                 return;
716         }
717
718         cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
719         memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
720         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
721 }
722 EXPORT_SYMBOL(transport_copy_sense_to_cmd);
723
724 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
725 {
726         struct se_device *dev = cmd->se_dev;
727         int success;
728         unsigned long flags;
729
730         cmd->scsi_status = scsi_status;
731
732         spin_lock_irqsave(&cmd->t_state_lock, flags);
733         switch (cmd->scsi_status) {
734         case SAM_STAT_CHECK_CONDITION:
735                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
736                         success = 1;
737                 else
738                         success = 0;
739                 break;
740         default:
741                 success = 1;
742                 break;
743         }
744
745         /*
746          * Check for case where an explicit ABORT_TASK has been received
747          * and transport_wait_for_tasks() will be waiting for completion..
748          */
749         if (cmd->transport_state & CMD_T_ABORTED ||
750             cmd->transport_state & CMD_T_STOP) {
751                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
752                 /*
753                  * If COMPARE_AND_WRITE was stopped by __transport_wait_for_tasks(),
754                  * release se_device->caw_sem obtained by sbc_compare_and_write()
755                  * since target_complete_ok_work() or target_complete_failure_work()
756                  * won't be called to invoke the normal CAW completion callbacks.
757                  */
758                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
759                         up(&dev->caw_sem);
760                 }
761                 complete_all(&cmd->t_transport_stop_comp);
762                 return;
763         } else if (!success) {
764                 INIT_WORK(&cmd->work, target_complete_failure_work);
765         } else {
766                 INIT_WORK(&cmd->work, target_complete_ok_work);
767         }
768
769         cmd->t_state = TRANSPORT_COMPLETE;
770         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
771         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
772
773         if (cmd->se_cmd_flags & SCF_USE_CPUID)
774                 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
775         else
776                 queue_work(target_completion_wq, &cmd->work);
777 }
778 EXPORT_SYMBOL(target_complete_cmd);
779
780 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
781 {
782         if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
783                 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
784                         cmd->residual_count += cmd->data_length - length;
785                 } else {
786                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
787                         cmd->residual_count = cmd->data_length - length;
788                 }
789
790                 cmd->data_length = length;
791         }
792
793         target_complete_cmd(cmd, scsi_status);
794 }
795 EXPORT_SYMBOL(target_complete_cmd_with_length);
796
797 static void target_add_to_state_list(struct se_cmd *cmd)
798 {
799         struct se_device *dev = cmd->se_dev;
800         unsigned long flags;
801
802         spin_lock_irqsave(&dev->execute_task_lock, flags);
803         if (!cmd->state_active) {
804                 list_add_tail(&cmd->state_list, &dev->state_list);
805                 cmd->state_active = true;
806         }
807         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
808 }
809
810 /*
811  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
812  */
813 static void transport_write_pending_qf(struct se_cmd *cmd);
814 static void transport_complete_qf(struct se_cmd *cmd);
815
816 void target_qf_do_work(struct work_struct *work)
817 {
818         struct se_device *dev = container_of(work, struct se_device,
819                                         qf_work_queue);
820         LIST_HEAD(qf_cmd_list);
821         struct se_cmd *cmd, *cmd_tmp;
822
823         spin_lock_irq(&dev->qf_cmd_lock);
824         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
825         spin_unlock_irq(&dev->qf_cmd_lock);
826
827         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
828                 list_del(&cmd->se_qf_node);
829                 atomic_dec_mb(&dev->dev_qf_count);
830
831                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
832                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
833                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
834                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
835                         : "UNKNOWN");
836
837                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
838                         transport_write_pending_qf(cmd);
839                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
840                          cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
841                         transport_complete_qf(cmd);
842         }
843 }
844
845 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
846 {
847         switch (cmd->data_direction) {
848         case DMA_NONE:
849                 return "NONE";
850         case DMA_FROM_DEVICE:
851                 return "READ";
852         case DMA_TO_DEVICE:
853                 return "WRITE";
854         case DMA_BIDIRECTIONAL:
855                 return "BIDI";
856         default:
857                 break;
858         }
859
860         return "UNKNOWN";
861 }
862
863 void transport_dump_dev_state(
864         struct se_device *dev,
865         char *b,
866         int *bl)
867 {
868         *bl += sprintf(b + *bl, "Status: ");
869         if (dev->export_count)
870                 *bl += sprintf(b + *bl, "ACTIVATED");
871         else
872                 *bl += sprintf(b + *bl, "DEACTIVATED");
873
874         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
875         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
876                 dev->dev_attrib.block_size,
877                 dev->dev_attrib.hw_max_sectors);
878         *bl += sprintf(b + *bl, "        ");
879 }
880
881 void transport_dump_vpd_proto_id(
882         struct t10_vpd *vpd,
883         unsigned char *p_buf,
884         int p_buf_len)
885 {
886         unsigned char buf[VPD_TMP_BUF_SIZE];
887         int len;
888
889         memset(buf, 0, VPD_TMP_BUF_SIZE);
890         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
891
892         switch (vpd->protocol_identifier) {
893         case 0x00:
894                 sprintf(buf+len, "Fibre Channel\n");
895                 break;
896         case 0x10:
897                 sprintf(buf+len, "Parallel SCSI\n");
898                 break;
899         case 0x20:
900                 sprintf(buf+len, "SSA\n");
901                 break;
902         case 0x30:
903                 sprintf(buf+len, "IEEE 1394\n");
904                 break;
905         case 0x40:
906                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
907                                 " Protocol\n");
908                 break;
909         case 0x50:
910                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
911                 break;
912         case 0x60:
913                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
914                 break;
915         case 0x70:
916                 sprintf(buf+len, "Automation/Drive Interface Transport"
917                                 " Protocol\n");
918                 break;
919         case 0x80:
920                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
921                 break;
922         default:
923                 sprintf(buf+len, "Unknown 0x%02x\n",
924                                 vpd->protocol_identifier);
925                 break;
926         }
927
928         if (p_buf)
929                 strncpy(p_buf, buf, p_buf_len);
930         else
931                 pr_debug("%s", buf);
932 }
933
934 void
935 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
936 {
937         /*
938          * Check if the Protocol Identifier Valid (PIV) bit is set..
939          *
940          * from spc3r23.pdf section 7.5.1
941          */
942          if (page_83[1] & 0x80) {
943                 vpd->protocol_identifier = (page_83[0] & 0xf0);
944                 vpd->protocol_identifier_set = 1;
945                 transport_dump_vpd_proto_id(vpd, NULL, 0);
946         }
947 }
948 EXPORT_SYMBOL(transport_set_vpd_proto_id);
949
950 int transport_dump_vpd_assoc(
951         struct t10_vpd *vpd,
952         unsigned char *p_buf,
953         int p_buf_len)
954 {
955         unsigned char buf[VPD_TMP_BUF_SIZE];
956         int ret = 0;
957         int len;
958
959         memset(buf, 0, VPD_TMP_BUF_SIZE);
960         len = sprintf(buf, "T10 VPD Identifier Association: ");
961
962         switch (vpd->association) {
963         case 0x00:
964                 sprintf(buf+len, "addressed logical unit\n");
965                 break;
966         case 0x10:
967                 sprintf(buf+len, "target port\n");
968                 break;
969         case 0x20:
970                 sprintf(buf+len, "SCSI target device\n");
971                 break;
972         default:
973                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
974                 ret = -EINVAL;
975                 break;
976         }
977
978         if (p_buf)
979                 strncpy(p_buf, buf, p_buf_len);
980         else
981                 pr_debug("%s", buf);
982
983         return ret;
984 }
985
986 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
987 {
988         /*
989          * The VPD identification association..
990          *
991          * from spc3r23.pdf Section 7.6.3.1 Table 297
992          */
993         vpd->association = (page_83[1] & 0x30);
994         return transport_dump_vpd_assoc(vpd, NULL, 0);
995 }
996 EXPORT_SYMBOL(transport_set_vpd_assoc);
997
998 int transport_dump_vpd_ident_type(
999         struct t10_vpd *vpd,
1000         unsigned char *p_buf,
1001         int p_buf_len)
1002 {
1003         unsigned char buf[VPD_TMP_BUF_SIZE];
1004         int ret = 0;
1005         int len;
1006
1007         memset(buf, 0, VPD_TMP_BUF_SIZE);
1008         len = sprintf(buf, "T10 VPD Identifier Type: ");
1009
1010         switch (vpd->device_identifier_type) {
1011         case 0x00:
1012                 sprintf(buf+len, "Vendor specific\n");
1013                 break;
1014         case 0x01:
1015                 sprintf(buf+len, "T10 Vendor ID based\n");
1016                 break;
1017         case 0x02:
1018                 sprintf(buf+len, "EUI-64 based\n");
1019                 break;
1020         case 0x03:
1021                 sprintf(buf+len, "NAA\n");
1022                 break;
1023         case 0x04:
1024                 sprintf(buf+len, "Relative target port identifier\n");
1025                 break;
1026         case 0x08:
1027                 sprintf(buf+len, "SCSI name string\n");
1028                 break;
1029         default:
1030                 sprintf(buf+len, "Unsupported: 0x%02x\n",
1031                                 vpd->device_identifier_type);
1032                 ret = -EINVAL;
1033                 break;
1034         }
1035
1036         if (p_buf) {
1037                 if (p_buf_len < strlen(buf)+1)
1038                         return -EINVAL;
1039                 strncpy(p_buf, buf, p_buf_len);
1040         } else {
1041                 pr_debug("%s", buf);
1042         }
1043
1044         return ret;
1045 }
1046
1047 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1048 {
1049         /*
1050          * The VPD identifier type..
1051          *
1052          * from spc3r23.pdf Section 7.6.3.1 Table 298
1053          */
1054         vpd->device_identifier_type = (page_83[1] & 0x0f);
1055         return transport_dump_vpd_ident_type(vpd, NULL, 0);
1056 }
1057 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1058
1059 int transport_dump_vpd_ident(
1060         struct t10_vpd *vpd,
1061         unsigned char *p_buf,
1062         int p_buf_len)
1063 {
1064         unsigned char buf[VPD_TMP_BUF_SIZE];
1065         int ret = 0;
1066
1067         memset(buf, 0, VPD_TMP_BUF_SIZE);
1068
1069         switch (vpd->device_identifier_code_set) {
1070         case 0x01: /* Binary */
1071                 snprintf(buf, sizeof(buf),
1072                         "T10 VPD Binary Device Identifier: %s\n",
1073                         &vpd->device_identifier[0]);
1074                 break;
1075         case 0x02: /* ASCII */
1076                 snprintf(buf, sizeof(buf),
1077                         "T10 VPD ASCII Device Identifier: %s\n",
1078                         &vpd->device_identifier[0]);
1079                 break;
1080         case 0x03: /* UTF-8 */
1081                 snprintf(buf, sizeof(buf),
1082                         "T10 VPD UTF-8 Device Identifier: %s\n",
1083                         &vpd->device_identifier[0]);
1084                 break;
1085         default:
1086                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1087                         " 0x%02x", vpd->device_identifier_code_set);
1088                 ret = -EINVAL;
1089                 break;
1090         }
1091
1092         if (p_buf)
1093                 strncpy(p_buf, buf, p_buf_len);
1094         else
1095                 pr_debug("%s", buf);
1096
1097         return ret;
1098 }
1099
1100 int
1101 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1102 {
1103         static const char hex_str[] = "0123456789abcdef";
1104         int j = 0, i = 4; /* offset to start of the identifier */
1105
1106         /*
1107          * The VPD Code Set (encoding)
1108          *
1109          * from spc3r23.pdf Section 7.6.3.1 Table 296
1110          */
1111         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1112         switch (vpd->device_identifier_code_set) {
1113         case 0x01: /* Binary */
1114                 vpd->device_identifier[j++] =
1115                                 hex_str[vpd->device_identifier_type];
1116                 while (i < (4 + page_83[3])) {
1117                         vpd->device_identifier[j++] =
1118                                 hex_str[(page_83[i] & 0xf0) >> 4];
1119                         vpd->device_identifier[j++] =
1120                                 hex_str[page_83[i] & 0x0f];
1121                         i++;
1122                 }
1123                 break;
1124         case 0x02: /* ASCII */
1125         case 0x03: /* UTF-8 */
1126                 while (i < (4 + page_83[3]))
1127                         vpd->device_identifier[j++] = page_83[i++];
1128                 break;
1129         default:
1130                 break;
1131         }
1132
1133         return transport_dump_vpd_ident(vpd, NULL, 0);
1134 }
1135 EXPORT_SYMBOL(transport_set_vpd_ident);
1136
1137 static sense_reason_t
1138 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1139                                unsigned int size)
1140 {
1141         u32 mtl;
1142
1143         if (!cmd->se_tfo->max_data_sg_nents)
1144                 return TCM_NO_SENSE;
1145         /*
1146          * Check if fabric enforced maximum SGL entries per I/O descriptor
1147          * exceeds se_cmd->data_length.  If true, set SCF_UNDERFLOW_BIT +
1148          * residual_count and reduce original cmd->data_length to maximum
1149          * length based on single PAGE_SIZE entry scatter-lists.
1150          */
1151         mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1152         if (cmd->data_length > mtl) {
1153                 /*
1154                  * If an existing CDB overflow is present, calculate new residual
1155                  * based on CDB size minus fabric maximum transfer length.
1156                  *
1157                  * If an existing CDB underflow is present, calculate new residual
1158                  * based on original cmd->data_length minus fabric maximum transfer
1159                  * length.
1160                  *
1161                  * Otherwise, set the underflow residual based on cmd->data_length
1162                  * minus fabric maximum transfer length.
1163                  */
1164                 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1165                         cmd->residual_count = (size - mtl);
1166                 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1167                         u32 orig_dl = size + cmd->residual_count;
1168                         cmd->residual_count = (orig_dl - mtl);
1169                 } else {
1170                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1171                         cmd->residual_count = (cmd->data_length - mtl);
1172                 }
1173                 cmd->data_length = mtl;
1174                 /*
1175                  * Reset sbc_check_prot() calculated protection payload
1176                  * length based upon the new smaller MTL.
1177                  */
1178                 if (cmd->prot_length) {
1179                         u32 sectors = (mtl / dev->dev_attrib.block_size);
1180                         cmd->prot_length = dev->prot_length * sectors;
1181                 }
1182         }
1183         return TCM_NO_SENSE;
1184 }
1185
1186 sense_reason_t
1187 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1188 {
1189         struct se_device *dev = cmd->se_dev;
1190
1191         if (cmd->unknown_data_length) {
1192                 cmd->data_length = size;
1193         } else if (size != cmd->data_length) {
1194                 pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1195                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1196                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1197                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1198
1199                 if (cmd->data_direction == DMA_TO_DEVICE) {
1200                         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1201                                 pr_err_ratelimited("Rejecting underflow/overflow"
1202                                                    " for WRITE data CDB\n");
1203                                 return TCM_INVALID_CDB_FIELD;
1204                         }
1205                         /*
1206                          * Some fabric drivers like iscsi-target still expect to
1207                          * always reject overflow writes.  Reject this case until
1208                          * full fabric driver level support for overflow writes
1209                          * is introduced tree-wide.
1210                          */
1211                         if (size > cmd->data_length) {
1212                                 pr_err_ratelimited("Rejecting overflow for"
1213                                                    " WRITE control CDB\n");
1214                                 return TCM_INVALID_CDB_FIELD;
1215                         }
1216                 }
1217                 /*
1218                  * Reject READ_* or WRITE_* with overflow/underflow for
1219                  * type SCF_SCSI_DATA_CDB.
1220                  */
1221                 if (dev->dev_attrib.block_size != 512)  {
1222                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1223                                 " CDB on non 512-byte sector setup subsystem"
1224                                 " plugin: %s\n", dev->transport->name);
1225                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1226                         return TCM_INVALID_CDB_FIELD;
1227                 }
1228                 /*
1229                  * For the overflow case keep the existing fabric provided
1230                  * ->data_length.  Otherwise for the underflow case, reset
1231                  * ->data_length to the smaller SCSI expected data transfer
1232                  * length.
1233                  */
1234                 if (size > cmd->data_length) {
1235                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1236                         cmd->residual_count = (size - cmd->data_length);
1237                 } else {
1238                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1239                         cmd->residual_count = (cmd->data_length - size);
1240                         cmd->data_length = size;
1241                 }
1242         }
1243
1244         return target_check_max_data_sg_nents(cmd, dev, size);
1245
1246 }
1247
1248 /*
1249  * Used by fabric modules containing a local struct se_cmd within their
1250  * fabric dependent per I/O descriptor.
1251  *
1252  * Preserves the value of @cmd->tag.
1253  */
1254 void transport_init_se_cmd(
1255         struct se_cmd *cmd,
1256         const struct target_core_fabric_ops *tfo,
1257         struct se_session *se_sess,
1258         u32 data_length,
1259         int data_direction,
1260         int task_attr,
1261         unsigned char *sense_buffer)
1262 {
1263         INIT_LIST_HEAD(&cmd->se_delayed_node);
1264         INIT_LIST_HEAD(&cmd->se_qf_node);
1265         INIT_LIST_HEAD(&cmd->se_cmd_list);
1266         INIT_LIST_HEAD(&cmd->state_list);
1267         init_completion(&cmd->t_transport_stop_comp);
1268         init_completion(&cmd->cmd_wait_comp);
1269         spin_lock_init(&cmd->t_state_lock);
1270         INIT_WORK(&cmd->work, NULL);
1271         kref_init(&cmd->cmd_kref);
1272
1273         cmd->se_tfo = tfo;
1274         cmd->se_sess = se_sess;
1275         cmd->data_length = data_length;
1276         cmd->data_direction = data_direction;
1277         cmd->sam_task_attr = task_attr;
1278         cmd->sense_buffer = sense_buffer;
1279
1280         cmd->state_active = false;
1281 }
1282 EXPORT_SYMBOL(transport_init_se_cmd);
1283
1284 static sense_reason_t
1285 transport_check_alloc_task_attr(struct se_cmd *cmd)
1286 {
1287         struct se_device *dev = cmd->se_dev;
1288
1289         /*
1290          * Check if SAM Task Attribute emulation is enabled for this
1291          * struct se_device storage object
1292          */
1293         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1294                 return 0;
1295
1296         if (cmd->sam_task_attr == TCM_ACA_TAG) {
1297                 pr_debug("SAM Task Attribute ACA"
1298                         " emulation is not supported\n");
1299                 return TCM_INVALID_CDB_FIELD;
1300         }
1301
1302         return 0;
1303 }
1304
1305 sense_reason_t
1306 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1307 {
1308         struct se_device *dev = cmd->se_dev;
1309         sense_reason_t ret;
1310
1311         /*
1312          * Ensure that the received CDB is less than the max (252 + 8) bytes
1313          * for VARIABLE_LENGTH_CMD
1314          */
1315         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1316                 pr_err("Received SCSI CDB with command_size: %d that"
1317                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1318                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1319                 return TCM_INVALID_CDB_FIELD;
1320         }
1321         /*
1322          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1323          * allocate the additional extended CDB buffer now..  Otherwise
1324          * setup the pointer from __t_task_cdb to t_task_cdb.
1325          */
1326         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1327                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1328                                                 GFP_KERNEL);
1329                 if (!cmd->t_task_cdb) {
1330                         pr_err("Unable to allocate cmd->t_task_cdb"
1331                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1332                                 scsi_command_size(cdb),
1333                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1334                         return TCM_OUT_OF_RESOURCES;
1335                 }
1336         } else
1337                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1338         /*
1339          * Copy the original CDB into cmd->
1340          */
1341         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1342
1343         trace_target_sequencer_start(cmd);
1344
1345         ret = dev->transport->parse_cdb(cmd);
1346         if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1347                 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1348                                     cmd->se_tfo->get_fabric_name(),
1349                                     cmd->se_sess->se_node_acl->initiatorname,
1350                                     cmd->t_task_cdb[0]);
1351         if (ret)
1352                 return ret;
1353
1354         ret = transport_check_alloc_task_attr(cmd);
1355         if (ret)
1356                 return ret;
1357
1358         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1359         atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1360         return 0;
1361 }
1362 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1363
1364 /*
1365  * Used by fabric module frontends to queue tasks directly.
1366  * May only be used from process context.
1367  */
1368 int transport_handle_cdb_direct(
1369         struct se_cmd *cmd)
1370 {
1371         sense_reason_t ret;
1372
1373         if (!cmd->se_lun) {
1374                 dump_stack();
1375                 pr_err("cmd->se_lun is NULL\n");
1376                 return -EINVAL;
1377         }
1378         if (in_interrupt()) {
1379                 dump_stack();
1380                 pr_err("transport_generic_handle_cdb cannot be called"
1381                                 " from interrupt context\n");
1382                 return -EINVAL;
1383         }
1384         /*
1385          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1386          * outstanding descriptors are handled correctly during shutdown via
1387          * transport_wait_for_tasks()
1388          *
1389          * Also, we don't take cmd->t_state_lock here as we only expect
1390          * this to be called for initial descriptor submission.
1391          */
1392         cmd->t_state = TRANSPORT_NEW_CMD;
1393         cmd->transport_state |= CMD_T_ACTIVE;
1394
1395         /*
1396          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1397          * so follow TRANSPORT_NEW_CMD processing thread context usage
1398          * and call transport_generic_request_failure() if necessary..
1399          */
1400         ret = transport_generic_new_cmd(cmd);
1401         if (ret)
1402                 transport_generic_request_failure(cmd, ret);
1403         return 0;
1404 }
1405 EXPORT_SYMBOL(transport_handle_cdb_direct);
1406
1407 sense_reason_t
1408 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1409                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1410 {
1411         if (!sgl || !sgl_count)
1412                 return 0;
1413
1414         /*
1415          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1416          * scatterlists already have been set to follow what the fabric
1417          * passes for the original expected data transfer length.
1418          */
1419         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1420                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1421                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1422                 return TCM_INVALID_CDB_FIELD;
1423         }
1424
1425         cmd->t_data_sg = sgl;
1426         cmd->t_data_nents = sgl_count;
1427         cmd->t_bidi_data_sg = sgl_bidi;
1428         cmd->t_bidi_data_nents = sgl_bidi_count;
1429
1430         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1431         return 0;
1432 }
1433
1434 /*
1435  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1436  *                       se_cmd + use pre-allocated SGL memory.
1437  *
1438  * @se_cmd: command descriptor to submit
1439  * @se_sess: associated se_sess for endpoint
1440  * @cdb: pointer to SCSI CDB
1441  * @sense: pointer to SCSI sense buffer
1442  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1443  * @data_length: fabric expected data transfer length
1444  * @task_addr: SAM task attribute
1445  * @data_dir: DMA data direction
1446  * @flags: flags for command submission from target_sc_flags_tables
1447  * @sgl: struct scatterlist memory for unidirectional mapping
1448  * @sgl_count: scatterlist count for unidirectional mapping
1449  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1450  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1451  * @sgl_prot: struct scatterlist memory protection information
1452  * @sgl_prot_count: scatterlist count for protection information
1453  *
1454  * Task tags are supported if the caller has set @se_cmd->tag.
1455  *
1456  * Returns non zero to signal active I/O shutdown failure.  All other
1457  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1458  * but still return zero here.
1459  *
1460  * This may only be called from process context, and also currently
1461  * assumes internal allocation of fabric payload buffer by target-core.
1462  */
1463 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1464                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1465                 u32 data_length, int task_attr, int data_dir, int flags,
1466                 struct scatterlist *sgl, u32 sgl_count,
1467                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1468                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1469 {
1470         struct se_portal_group *se_tpg;
1471         sense_reason_t rc;
1472         int ret;
1473
1474         se_tpg = se_sess->se_tpg;
1475         BUG_ON(!se_tpg);
1476         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1477         BUG_ON(in_interrupt());
1478         /*
1479          * Initialize se_cmd for target operation.  From this point
1480          * exceptions are handled by sending exception status via
1481          * target_core_fabric_ops->queue_status() callback
1482          */
1483         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1484                                 data_length, data_dir, task_attr, sense);
1485
1486         if (flags & TARGET_SCF_USE_CPUID)
1487                 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1488         else
1489                 se_cmd->cpuid = WORK_CPU_UNBOUND;
1490
1491         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1492                 se_cmd->unknown_data_length = 1;
1493         /*
1494          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1495          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1496          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1497          * kref_put() to happen during fabric packet acknowledgement.
1498          */
1499         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1500         if (ret)
1501                 return ret;
1502         /*
1503          * Signal bidirectional data payloads to target-core
1504          */
1505         if (flags & TARGET_SCF_BIDI_OP)
1506                 se_cmd->se_cmd_flags |= SCF_BIDI;
1507         /*
1508          * Locate se_lun pointer and attach it to struct se_cmd
1509          */
1510         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1511         if (rc) {
1512                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1513                 target_put_sess_cmd(se_cmd);
1514                 return 0;
1515         }
1516
1517         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1518         if (rc != 0) {
1519                 transport_generic_request_failure(se_cmd, rc);
1520                 return 0;
1521         }
1522
1523         /*
1524          * Save pointers for SGLs containing protection information,
1525          * if present.
1526          */
1527         if (sgl_prot_count) {
1528                 se_cmd->t_prot_sg = sgl_prot;
1529                 se_cmd->t_prot_nents = sgl_prot_count;
1530                 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1531         }
1532
1533         /*
1534          * When a non zero sgl_count has been passed perform SGL passthrough
1535          * mapping for pre-allocated fabric memory instead of having target
1536          * core perform an internal SGL allocation..
1537          */
1538         if (sgl_count != 0) {
1539                 BUG_ON(!sgl);
1540
1541                 /*
1542                  * A work-around for tcm_loop as some userspace code via
1543                  * scsi-generic do not memset their associated read buffers,
1544                  * so go ahead and do that here for type non-data CDBs.  Also
1545                  * note that this is currently guaranteed to be a single SGL
1546                  * for this case by target core in target_setup_cmd_from_cdb()
1547                  * -> transport_generic_cmd_sequencer().
1548                  */
1549                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1550                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1551                         unsigned char *buf = NULL;
1552
1553                         if (sgl)
1554                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1555
1556                         if (buf) {
1557                                 memset(buf, 0, sgl->length);
1558                                 kunmap(sg_page(sgl));
1559                         }
1560                 }
1561
1562                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1563                                 sgl_bidi, sgl_bidi_count);
1564                 if (rc != 0) {
1565                         transport_generic_request_failure(se_cmd, rc);
1566                         return 0;
1567                 }
1568         }
1569
1570         /*
1571          * Check if we need to delay processing because of ALUA
1572          * Active/NonOptimized primary access state..
1573          */
1574         core_alua_check_nonop_delay(se_cmd);
1575
1576         transport_handle_cdb_direct(se_cmd);
1577         return 0;
1578 }
1579 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1580
1581 /*
1582  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1583  *
1584  * @se_cmd: command descriptor to submit
1585  * @se_sess: associated se_sess for endpoint
1586  * @cdb: pointer to SCSI CDB
1587  * @sense: pointer to SCSI sense buffer
1588  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1589  * @data_length: fabric expected data transfer length
1590  * @task_addr: SAM task attribute
1591  * @data_dir: DMA data direction
1592  * @flags: flags for command submission from target_sc_flags_tables
1593  *
1594  * Task tags are supported if the caller has set @se_cmd->tag.
1595  *
1596  * Returns non zero to signal active I/O shutdown failure.  All other
1597  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1598  * but still return zero here.
1599  *
1600  * This may only be called from process context, and also currently
1601  * assumes internal allocation of fabric payload buffer by target-core.
1602  *
1603  * It also assumes interal target core SGL memory allocation.
1604  */
1605 int target_submit_cmd(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 {
1609         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1610                         unpacked_lun, data_length, task_attr, data_dir,
1611                         flags, NULL, 0, NULL, 0, NULL, 0);
1612 }
1613 EXPORT_SYMBOL(target_submit_cmd);
1614
1615 static void target_complete_tmr_failure(struct work_struct *work)
1616 {
1617         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1618
1619         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1620         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1621
1622         transport_lun_remove_cmd(se_cmd);
1623         transport_cmd_check_stop_to_fabric(se_cmd);
1624 }
1625
1626 static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
1627                                        u64 *unpacked_lun)
1628 {
1629         struct se_cmd *se_cmd;
1630         unsigned long flags;
1631         bool ret = false;
1632
1633         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
1634         list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
1635                 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1636                         continue;
1637
1638                 if (se_cmd->tag == tag) {
1639                         *unpacked_lun = se_cmd->orig_fe_lun;
1640                         ret = true;
1641                         break;
1642                 }
1643         }
1644         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
1645
1646         return ret;
1647 }
1648
1649 /**
1650  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1651  *                     for TMR CDBs
1652  *
1653  * @se_cmd: command descriptor to submit
1654  * @se_sess: associated se_sess for endpoint
1655  * @sense: pointer to SCSI sense buffer
1656  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1657  * @fabric_context: fabric context for TMR req
1658  * @tm_type: Type of TM request
1659  * @gfp: gfp type for caller
1660  * @tag: referenced task tag for TMR_ABORT_TASK
1661  * @flags: submit cmd flags
1662  *
1663  * Callable from all contexts.
1664  **/
1665
1666 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1667                 unsigned char *sense, u64 unpacked_lun,
1668                 void *fabric_tmr_ptr, unsigned char tm_type,
1669                 gfp_t gfp, u64 tag, int flags)
1670 {
1671         struct se_portal_group *se_tpg;
1672         int ret;
1673
1674         se_tpg = se_sess->se_tpg;
1675         BUG_ON(!se_tpg);
1676
1677         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1678                               0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1679         /*
1680          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1681          * allocation failure.
1682          */
1683         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1684         if (ret < 0)
1685                 return -ENOMEM;
1686
1687         if (tm_type == TMR_ABORT_TASK)
1688                 se_cmd->se_tmr_req->ref_task_tag = tag;
1689
1690         /* See target_submit_cmd for commentary */
1691         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1692         if (ret) {
1693                 core_tmr_release_req(se_cmd->se_tmr_req);
1694                 return ret;
1695         }
1696         /*
1697          * If this is ABORT_TASK with no explicit fabric provided LUN,
1698          * go ahead and search active session tags for a match to figure
1699          * out unpacked_lun for the original se_cmd.
1700          */
1701         if (tm_type == TMR_ABORT_TASK && (flags & TARGET_SCF_LOOKUP_LUN_FROM_TAG)) {
1702                 if (!target_lookup_lun_from_tag(se_sess, tag, &unpacked_lun))
1703                         goto failure;
1704         }
1705
1706         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1707         if (ret)
1708                 goto failure;
1709
1710         transport_generic_handle_tmr(se_cmd);
1711         return 0;
1712
1713         /*
1714          * For callback during failure handling, push this work off
1715          * to process context with TMR_LUN_DOES_NOT_EXIST status.
1716          */
1717 failure:
1718         INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1719         schedule_work(&se_cmd->work);
1720         return 0;
1721 }
1722 EXPORT_SYMBOL(target_submit_tmr);
1723
1724 /*
1725  * Handle SAM-esque emulation for generic transport request failures.
1726  */
1727 void transport_generic_request_failure(struct se_cmd *cmd,
1728                 sense_reason_t sense_reason)
1729 {
1730         int ret = 0, post_ret = 0;
1731
1732         pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
1733                  sense_reason);
1734         target_show_cmd("-----[ ", cmd);
1735
1736         /*
1737          * For SAM Task Attribute emulation for failed struct se_cmd
1738          */
1739         transport_complete_task_attr(cmd);
1740
1741         /*
1742          * Handle special case for COMPARE_AND_WRITE failure, where the
1743          * callback is expected to drop the per device ->caw_sem.
1744          */
1745         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1746              cmd->transport_complete_callback)
1747                 cmd->transport_complete_callback(cmd, false, &post_ret);
1748
1749         if (transport_check_aborted_status(cmd, 1))
1750                 return;
1751
1752         switch (sense_reason) {
1753         case TCM_NON_EXISTENT_LUN:
1754         case TCM_UNSUPPORTED_SCSI_OPCODE:
1755         case TCM_INVALID_CDB_FIELD:
1756         case TCM_INVALID_PARAMETER_LIST:
1757         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1758         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1759         case TCM_UNKNOWN_MODE_PAGE:
1760         case TCM_WRITE_PROTECTED:
1761         case TCM_ADDRESS_OUT_OF_RANGE:
1762         case TCM_CHECK_CONDITION_ABORT_CMD:
1763         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1764         case TCM_CHECK_CONDITION_NOT_READY:
1765         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1766         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1767         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1768         case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1769         case TCM_TOO_MANY_TARGET_DESCS:
1770         case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
1771         case TCM_TOO_MANY_SEGMENT_DESCS:
1772         case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
1773                 break;
1774         case TCM_OUT_OF_RESOURCES:
1775                 cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
1776                 goto queue_status;
1777         case TCM_LUN_BUSY:
1778                 cmd->scsi_status = SAM_STAT_BUSY;
1779                 goto queue_status;
1780         case TCM_RESERVATION_CONFLICT:
1781                 /*
1782                  * No SENSE Data payload for this case, set SCSI Status
1783                  * and queue the response to $FABRIC_MOD.
1784                  *
1785                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1786                  */
1787                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1788                 /*
1789                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1790                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1791                  * CONFLICT STATUS.
1792                  *
1793                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1794                  */
1795                 if (cmd->se_sess &&
1796                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1797                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1798                                                cmd->orig_fe_lun, 0x2C,
1799                                         ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1800                 }
1801
1802                 goto queue_status;
1803         default:
1804                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1805                         cmd->t_task_cdb[0], sense_reason);
1806                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1807                 break;
1808         }
1809
1810         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1811         if (ret)
1812                 goto queue_full;
1813
1814 check_stop:
1815         transport_lun_remove_cmd(cmd);
1816         transport_cmd_check_stop_to_fabric(cmd);
1817         return;
1818
1819 queue_status:
1820         trace_target_cmd_complete(cmd);
1821         ret = cmd->se_tfo->queue_status(cmd);
1822         if (!ret)
1823                 goto check_stop;
1824 queue_full:
1825         transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
1826 }
1827 EXPORT_SYMBOL(transport_generic_request_failure);
1828
1829 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1830 {
1831         sense_reason_t ret;
1832
1833         if (!cmd->execute_cmd) {
1834                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1835                 goto err;
1836         }
1837         if (do_checks) {
1838                 /*
1839                  * Check for an existing UNIT ATTENTION condition after
1840                  * target_handle_task_attr() has done SAM task attr
1841                  * checking, and possibly have already defered execution
1842                  * out to target_restart_delayed_cmds() context.
1843                  */
1844                 ret = target_scsi3_ua_check(cmd);
1845                 if (ret)
1846                         goto err;
1847
1848                 ret = target_alua_state_check(cmd);
1849                 if (ret)
1850                         goto err;
1851
1852                 ret = target_check_reservation(cmd);
1853                 if (ret) {
1854                         cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1855                         goto err;
1856                 }
1857         }
1858
1859         ret = cmd->execute_cmd(cmd);
1860         if (!ret)
1861                 return;
1862 err:
1863         spin_lock_irq(&cmd->t_state_lock);
1864         cmd->transport_state &= ~CMD_T_SENT;
1865         spin_unlock_irq(&cmd->t_state_lock);
1866
1867         transport_generic_request_failure(cmd, ret);
1868 }
1869
1870 static int target_write_prot_action(struct se_cmd *cmd)
1871 {
1872         u32 sectors;
1873         /*
1874          * Perform WRITE_INSERT of PI using software emulation when backend
1875          * device has PI enabled, if the transport has not already generated
1876          * PI using hardware WRITE_INSERT offload.
1877          */
1878         switch (cmd->prot_op) {
1879         case TARGET_PROT_DOUT_INSERT:
1880                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1881                         sbc_dif_generate(cmd);
1882                 break;
1883         case TARGET_PROT_DOUT_STRIP:
1884                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1885                         break;
1886
1887                 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1888                 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1889                                              sectors, 0, cmd->t_prot_sg, 0);
1890                 if (unlikely(cmd->pi_err)) {
1891                         spin_lock_irq(&cmd->t_state_lock);
1892                         cmd->transport_state &= ~CMD_T_SENT;
1893                         spin_unlock_irq(&cmd->t_state_lock);
1894                         transport_generic_request_failure(cmd, cmd->pi_err);
1895                         return -1;
1896                 }
1897                 break;
1898         default:
1899                 break;
1900         }
1901
1902         return 0;
1903 }
1904
1905 static bool target_handle_task_attr(struct se_cmd *cmd)
1906 {
1907         struct se_device *dev = cmd->se_dev;
1908
1909         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1910                 return false;
1911
1912         cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
1913
1914         /*
1915          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1916          * to allow the passed struct se_cmd list of tasks to the front of the list.
1917          */
1918         switch (cmd->sam_task_attr) {
1919         case TCM_HEAD_TAG:
1920                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1921                          cmd->t_task_cdb[0]);
1922                 return false;
1923         case TCM_ORDERED_TAG:
1924                 atomic_inc_mb(&dev->dev_ordered_sync);
1925
1926                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1927                          cmd->t_task_cdb[0]);
1928
1929                 /*
1930                  * Execute an ORDERED command if no other older commands
1931                  * exist that need to be completed first.
1932                  */
1933                 if (!atomic_read(&dev->simple_cmds))
1934                         return false;
1935                 break;
1936         default:
1937                 /*
1938                  * For SIMPLE and UNTAGGED Task Attribute commands
1939                  */
1940                 atomic_inc_mb(&dev->simple_cmds);
1941                 break;
1942         }
1943
1944         if (atomic_read(&dev->dev_ordered_sync) == 0)
1945                 return false;
1946
1947         spin_lock(&dev->delayed_cmd_lock);
1948         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1949         spin_unlock(&dev->delayed_cmd_lock);
1950
1951         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
1952                 cmd->t_task_cdb[0], cmd->sam_task_attr);
1953         return true;
1954 }
1955
1956 static int __transport_check_aborted_status(struct se_cmd *, int);
1957
1958 void target_execute_cmd(struct se_cmd *cmd)
1959 {
1960         /*
1961          * Determine if frontend context caller is requesting the stopping of
1962          * this command for frontend exceptions.
1963          *
1964          * If the received CDB has aleady been aborted stop processing it here.
1965          */
1966         spin_lock_irq(&cmd->t_state_lock);
1967         if (__transport_check_aborted_status(cmd, 1)) {
1968                 spin_unlock_irq(&cmd->t_state_lock);
1969                 return;
1970         }
1971         if (cmd->transport_state & CMD_T_STOP) {
1972                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1973                         __func__, __LINE__, cmd->tag);
1974
1975                 spin_unlock_irq(&cmd->t_state_lock);
1976                 complete_all(&cmd->t_transport_stop_comp);
1977                 return;
1978         }
1979
1980         cmd->t_state = TRANSPORT_PROCESSING;
1981         cmd->transport_state &= ~CMD_T_PRE_EXECUTE;
1982         cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
1983         spin_unlock_irq(&cmd->t_state_lock);
1984
1985         if (target_write_prot_action(cmd))
1986                 return;
1987
1988         if (target_handle_task_attr(cmd)) {
1989                 spin_lock_irq(&cmd->t_state_lock);
1990                 cmd->transport_state &= ~CMD_T_SENT;
1991                 spin_unlock_irq(&cmd->t_state_lock);
1992                 return;
1993         }
1994
1995         __target_execute_cmd(cmd, true);
1996 }
1997 EXPORT_SYMBOL(target_execute_cmd);
1998
1999 /*
2000  * Process all commands up to the last received ORDERED task attribute which
2001  * requires another blocking boundary
2002  */
2003 static void target_restart_delayed_cmds(struct se_device *dev)
2004 {
2005         for (;;) {
2006                 struct se_cmd *cmd;
2007
2008                 spin_lock(&dev->delayed_cmd_lock);
2009                 if (list_empty(&dev->delayed_cmd_list)) {
2010                         spin_unlock(&dev->delayed_cmd_lock);
2011                         break;
2012                 }
2013
2014                 cmd = list_entry(dev->delayed_cmd_list.next,
2015                                  struct se_cmd, se_delayed_node);
2016                 list_del(&cmd->se_delayed_node);
2017                 spin_unlock(&dev->delayed_cmd_lock);
2018
2019                 cmd->transport_state |= CMD_T_SENT;
2020
2021                 __target_execute_cmd(cmd, true);
2022
2023                 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
2024                         break;
2025         }
2026 }
2027
2028 /*
2029  * Called from I/O completion to determine which dormant/delayed
2030  * and ordered cmds need to have their tasks added to the execution queue.
2031  */
2032 static void transport_complete_task_attr(struct se_cmd *cmd)
2033 {
2034         struct se_device *dev = cmd->se_dev;
2035
2036         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2037                 return;
2038
2039         if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2040                 goto restart;
2041
2042         if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
2043                 atomic_dec_mb(&dev->simple_cmds);
2044                 dev->dev_cur_ordered_id++;
2045         } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
2046                 dev->dev_cur_ordered_id++;
2047                 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
2048                          dev->dev_cur_ordered_id);
2049         } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2050                 atomic_dec_mb(&dev->dev_ordered_sync);
2051
2052                 dev->dev_cur_ordered_id++;
2053                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
2054                          dev->dev_cur_ordered_id);
2055         }
2056         cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2057
2058 restart:
2059         target_restart_delayed_cmds(dev);
2060 }
2061
2062 static void transport_complete_qf(struct se_cmd *cmd)
2063 {
2064         int ret = 0;
2065
2066         transport_complete_task_attr(cmd);
2067         /*
2068          * If a fabric driver ->write_pending() or ->queue_data_in() callback
2069          * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2070          * the same callbacks should not be retried.  Return CHECK_CONDITION
2071          * if a scsi_status is not already set.
2072          *
2073          * If a fabric driver ->queue_status() has returned non zero, always
2074          * keep retrying no matter what..
2075          */
2076         if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2077                 if (cmd->scsi_status)
2078                         goto queue_status;
2079
2080                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2081                 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2082                 cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2083                 translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2084                 goto queue_status;
2085         }
2086
2087         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2088                 goto queue_status;
2089
2090         switch (cmd->data_direction) {
2091         case DMA_FROM_DEVICE:
2092                 if (cmd->scsi_status)
2093                         goto queue_status;
2094
2095                 trace_target_cmd_complete(cmd);
2096                 ret = cmd->se_tfo->queue_data_in(cmd);
2097                 break;
2098         case DMA_TO_DEVICE:
2099                 if (cmd->se_cmd_flags & SCF_BIDI) {
2100                         ret = cmd->se_tfo->queue_data_in(cmd);
2101                         break;
2102                 }
2103                 /* fall through */
2104         case DMA_NONE:
2105 queue_status:
2106                 trace_target_cmd_complete(cmd);
2107                 ret = cmd->se_tfo->queue_status(cmd);
2108                 break;
2109         default:
2110                 break;
2111         }
2112
2113         if (ret < 0) {
2114                 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2115                 return;
2116         }
2117         transport_lun_remove_cmd(cmd);
2118         transport_cmd_check_stop_to_fabric(cmd);
2119 }
2120
2121 static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2122                                         int err, bool write_pending)
2123 {
2124         /*
2125          * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2126          * ->queue_data_in() callbacks from new process context.
2127          *
2128          * Otherwise for other errors, transport_complete_qf() will send
2129          * CHECK_CONDITION via ->queue_status() instead of attempting to
2130          * retry associated fabric driver data-transfer callbacks.
2131          */
2132         if (err == -EAGAIN || err == -ENOMEM) {
2133                 cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2134                                                  TRANSPORT_COMPLETE_QF_OK;
2135         } else {
2136                 pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2137                 cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2138         }
2139
2140         spin_lock_irq(&dev->qf_cmd_lock);
2141         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2142         atomic_inc_mb(&dev->dev_qf_count);
2143         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2144
2145         schedule_work(&cmd->se_dev->qf_work_queue);
2146 }
2147
2148 static bool target_read_prot_action(struct se_cmd *cmd)
2149 {
2150         switch (cmd->prot_op) {
2151         case TARGET_PROT_DIN_STRIP:
2152                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2153                         u32 sectors = cmd->data_length >>
2154                                   ilog2(cmd->se_dev->dev_attrib.block_size);
2155
2156                         cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2157                                                      sectors, 0, cmd->t_prot_sg,
2158                                                      0);
2159                         if (cmd->pi_err)
2160                                 return true;
2161                 }
2162                 break;
2163         case TARGET_PROT_DIN_INSERT:
2164                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2165                         break;
2166
2167                 sbc_dif_generate(cmd);
2168                 break;
2169         default:
2170                 break;
2171         }
2172
2173         return false;
2174 }
2175
2176 static void target_complete_ok_work(struct work_struct *work)
2177 {
2178         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2179         int ret;
2180
2181         /*
2182          * Check if we need to move delayed/dormant tasks from cmds on the
2183          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2184          * Attribute.
2185          */
2186         transport_complete_task_attr(cmd);
2187
2188         /*
2189          * Check to schedule QUEUE_FULL work, or execute an existing
2190          * cmd->transport_qf_callback()
2191          */
2192         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2193                 schedule_work(&cmd->se_dev->qf_work_queue);
2194
2195         /*
2196          * Check if we need to send a sense buffer from
2197          * the struct se_cmd in question.
2198          */
2199         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2200                 WARN_ON(!cmd->scsi_status);
2201                 ret = transport_send_check_condition_and_sense(
2202                                         cmd, 0, 1);
2203                 if (ret)
2204                         goto queue_full;
2205
2206                 transport_lun_remove_cmd(cmd);
2207                 transport_cmd_check_stop_to_fabric(cmd);
2208                 return;
2209         }
2210         /*
2211          * Check for a callback, used by amongst other things
2212          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2213          */
2214         if (cmd->transport_complete_callback) {
2215                 sense_reason_t rc;
2216                 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2217                 bool zero_dl = !(cmd->data_length);
2218                 int post_ret = 0;
2219
2220                 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2221                 if (!rc && !post_ret) {
2222                         if (caw && zero_dl)
2223                                 goto queue_rsp;
2224
2225                         return;
2226                 } else if (rc) {
2227                         ret = transport_send_check_condition_and_sense(cmd,
2228                                                 rc, 0);
2229                         if (ret)
2230                                 goto queue_full;
2231
2232                         transport_lun_remove_cmd(cmd);
2233                         transport_cmd_check_stop_to_fabric(cmd);
2234                         return;
2235                 }
2236         }
2237
2238 queue_rsp:
2239         switch (cmd->data_direction) {
2240         case DMA_FROM_DEVICE:
2241                 if (cmd->scsi_status)
2242                         goto queue_status;
2243
2244                 atomic_long_add(cmd->data_length,
2245                                 &cmd->se_lun->lun_stats.tx_data_octets);
2246                 /*
2247                  * Perform READ_STRIP of PI using software emulation when
2248                  * backend had PI enabled, if the transport will not be
2249                  * performing hardware READ_STRIP offload.
2250                  */
2251                 if (target_read_prot_action(cmd)) {
2252                         ret = transport_send_check_condition_and_sense(cmd,
2253                                                 cmd->pi_err, 0);
2254                         if (ret)
2255                                 goto queue_full;
2256
2257                         transport_lun_remove_cmd(cmd);
2258                         transport_cmd_check_stop_to_fabric(cmd);
2259                         return;
2260                 }
2261
2262                 trace_target_cmd_complete(cmd);
2263                 ret = cmd->se_tfo->queue_data_in(cmd);
2264                 if (ret)
2265                         goto queue_full;
2266                 break;
2267         case DMA_TO_DEVICE:
2268                 atomic_long_add(cmd->data_length,
2269                                 &cmd->se_lun->lun_stats.rx_data_octets);
2270                 /*
2271                  * Check if we need to send READ payload for BIDI-COMMAND
2272                  */
2273                 if (cmd->se_cmd_flags & SCF_BIDI) {
2274                         atomic_long_add(cmd->data_length,
2275                                         &cmd->se_lun->lun_stats.tx_data_octets);
2276                         ret = cmd->se_tfo->queue_data_in(cmd);
2277                         if (ret)
2278                                 goto queue_full;
2279                         break;
2280                 }
2281                 /* fall through */
2282         case DMA_NONE:
2283 queue_status:
2284                 trace_target_cmd_complete(cmd);
2285                 ret = cmd->se_tfo->queue_status(cmd);
2286                 if (ret)
2287                         goto queue_full;
2288                 break;
2289         default:
2290                 break;
2291         }
2292
2293         transport_lun_remove_cmd(cmd);
2294         transport_cmd_check_stop_to_fabric(cmd);
2295         return;
2296
2297 queue_full:
2298         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2299                 " data_direction: %d\n", cmd, cmd->data_direction);
2300
2301         transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2302 }
2303
2304 void target_free_sgl(struct scatterlist *sgl, int nents)
2305 {
2306         sgl_free_n_order(sgl, nents, 0);
2307 }
2308 EXPORT_SYMBOL(target_free_sgl);
2309
2310 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2311 {
2312         /*
2313          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2314          * emulation, and free + reset pointers if necessary..
2315          */
2316         if (!cmd->t_data_sg_orig)
2317                 return;
2318
2319         kfree(cmd->t_data_sg);
2320         cmd->t_data_sg = cmd->t_data_sg_orig;
2321         cmd->t_data_sg_orig = NULL;
2322         cmd->t_data_nents = cmd->t_data_nents_orig;
2323         cmd->t_data_nents_orig = 0;
2324 }
2325
2326 static inline void transport_free_pages(struct se_cmd *cmd)
2327 {
2328         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2329                 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2330                 cmd->t_prot_sg = NULL;
2331                 cmd->t_prot_nents = 0;
2332         }
2333
2334         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2335                 /*
2336                  * Release special case READ buffer payload required for
2337                  * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2338                  */
2339                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2340                         target_free_sgl(cmd->t_bidi_data_sg,
2341                                            cmd->t_bidi_data_nents);
2342                         cmd->t_bidi_data_sg = NULL;
2343                         cmd->t_bidi_data_nents = 0;
2344                 }
2345                 transport_reset_sgl_orig(cmd);
2346                 return;
2347         }
2348         transport_reset_sgl_orig(cmd);
2349
2350         target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2351         cmd->t_data_sg = NULL;
2352         cmd->t_data_nents = 0;
2353
2354         target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2355         cmd->t_bidi_data_sg = NULL;
2356         cmd->t_bidi_data_nents = 0;
2357 }
2358
2359 void *transport_kmap_data_sg(struct se_cmd *cmd)
2360 {
2361         struct scatterlist *sg = cmd->t_data_sg;
2362         struct page **pages;
2363         int i;
2364
2365         /*
2366          * We need to take into account a possible offset here for fabrics like
2367          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2368          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2369          */
2370         if (!cmd->t_data_nents)
2371                 return NULL;
2372
2373         BUG_ON(!sg);
2374         if (cmd->t_data_nents == 1)
2375                 return kmap(sg_page(sg)) + sg->offset;
2376
2377         /* >1 page. use vmap */
2378         pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2379         if (!pages)
2380                 return NULL;
2381
2382         /* convert sg[] to pages[] */
2383         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2384                 pages[i] = sg_page(sg);
2385         }
2386
2387         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2388         kfree(pages);
2389         if (!cmd->t_data_vmap)
2390                 return NULL;
2391
2392         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2393 }
2394 EXPORT_SYMBOL(transport_kmap_data_sg);
2395
2396 void transport_kunmap_data_sg(struct se_cmd *cmd)
2397 {
2398         if (!cmd->t_data_nents) {
2399                 return;
2400         } else if (cmd->t_data_nents == 1) {
2401                 kunmap(sg_page(cmd->t_data_sg));
2402                 return;
2403         }
2404
2405         vunmap(cmd->t_data_vmap);
2406         cmd->t_data_vmap = NULL;
2407 }
2408 EXPORT_SYMBOL(transport_kunmap_data_sg);
2409
2410 int
2411 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2412                  bool zero_page, bool chainable)
2413 {
2414         gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2415
2416         *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2417         return *sgl ? 0 : -ENOMEM;
2418 }
2419 EXPORT_SYMBOL(target_alloc_sgl);
2420
2421 /*
2422  * Allocate any required resources to execute the command.  For writes we
2423  * might not have the payload yet, so notify the fabric via a call to
2424  * ->write_pending instead. Otherwise place it on the execution queue.
2425  */
2426 sense_reason_t
2427 transport_generic_new_cmd(struct se_cmd *cmd)
2428 {
2429         unsigned long flags;
2430         int ret = 0;
2431         bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2432
2433         if (cmd->prot_op != TARGET_PROT_NORMAL &&
2434             !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2435                 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2436                                        cmd->prot_length, true, false);
2437                 if (ret < 0)
2438                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2439         }
2440
2441         /*
2442          * Determine is the TCM fabric module has already allocated physical
2443          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2444          * beforehand.
2445          */
2446         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2447             cmd->data_length) {
2448
2449                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2450                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2451                         u32 bidi_length;
2452
2453                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2454                                 bidi_length = cmd->t_task_nolb *
2455                                               cmd->se_dev->dev_attrib.block_size;
2456                         else
2457                                 bidi_length = cmd->data_length;
2458
2459                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2460                                                &cmd->t_bidi_data_nents,
2461                                                bidi_length, zero_flag, false);
2462                         if (ret < 0)
2463                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2464                 }
2465
2466                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2467                                        cmd->data_length, zero_flag, false);
2468                 if (ret < 0)
2469                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2470         } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2471                     cmd->data_length) {
2472                 /*
2473                  * Special case for COMPARE_AND_WRITE with fabrics
2474                  * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2475                  */
2476                 u32 caw_length = cmd->t_task_nolb *
2477                                  cmd->se_dev->dev_attrib.block_size;
2478
2479                 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2480                                        &cmd->t_bidi_data_nents,
2481                                        caw_length, zero_flag, false);
2482                 if (ret < 0)
2483                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2484         }
2485         /*
2486          * If this command is not a write we can execute it right here,
2487          * for write buffers we need to notify the fabric driver first
2488          * and let it call back once the write buffers are ready.
2489          */
2490         target_add_to_state_list(cmd);
2491         if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2492                 target_execute_cmd(cmd);
2493                 return 0;
2494         }
2495
2496         spin_lock_irqsave(&cmd->t_state_lock, flags);
2497         cmd->t_state = TRANSPORT_WRITE_PENDING;
2498         /*
2499          * Determine if frontend context caller is requesting the stopping of
2500          * this command for frontend exceptions.
2501          */
2502         if (cmd->transport_state & CMD_T_STOP) {
2503                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2504                          __func__, __LINE__, cmd->tag);
2505
2506                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2507
2508                 complete_all(&cmd->t_transport_stop_comp);
2509                 return 0;
2510         }
2511         cmd->transport_state &= ~CMD_T_ACTIVE;
2512         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2513
2514         ret = cmd->se_tfo->write_pending(cmd);
2515         if (ret)
2516                 goto queue_full;
2517
2518         return 0;
2519
2520 queue_full:
2521         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2522         transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2523         return 0;
2524 }
2525 EXPORT_SYMBOL(transport_generic_new_cmd);
2526
2527 static void transport_write_pending_qf(struct se_cmd *cmd)
2528 {
2529         unsigned long flags;
2530         int ret;
2531         bool stop;
2532
2533         spin_lock_irqsave(&cmd->t_state_lock, flags);
2534         stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2535         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2536
2537         if (stop) {
2538                 pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2539                         __func__, __LINE__, cmd->tag);
2540                 complete_all(&cmd->t_transport_stop_comp);
2541                 return;
2542         }
2543
2544         ret = cmd->se_tfo->write_pending(cmd);
2545         if (ret) {
2546                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2547                          cmd);
2548                 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2549         }
2550 }
2551
2552 static bool
2553 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2554                            unsigned long *flags);
2555
2556 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2557 {
2558         unsigned long flags;
2559
2560         spin_lock_irqsave(&cmd->t_state_lock, flags);
2561         __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2562         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2563 }
2564
2565 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2566 {
2567         int ret = 0;
2568         bool aborted = false, tas = false;
2569
2570         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2571                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2572                         target_wait_free_cmd(cmd, &aborted, &tas);
2573
2574                 if (!aborted || tas)
2575                         ret = target_put_sess_cmd(cmd);
2576         } else {
2577                 if (wait_for_tasks)
2578                         target_wait_free_cmd(cmd, &aborted, &tas);
2579                 /*
2580                  * Handle WRITE failure case where transport_generic_new_cmd()
2581                  * has already added se_cmd to state_list, but fabric has
2582                  * failed command before I/O submission.
2583                  */
2584                 if (cmd->state_active)
2585                         target_remove_from_state_list(cmd);
2586
2587                 if (cmd->se_lun)
2588                         transport_lun_remove_cmd(cmd);
2589
2590                 if (!aborted || tas)
2591                         ret = target_put_sess_cmd(cmd);
2592         }
2593         /*
2594          * If the task has been internally aborted due to TMR ABORT_TASK
2595          * or LUN_RESET, target_core_tmr.c is responsible for performing
2596          * the remaining calls to target_put_sess_cmd(), and not the
2597          * callers of this function.
2598          */
2599         if (aborted) {
2600                 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2601                 wait_for_completion(&cmd->cmd_wait_comp);
2602                 cmd->se_tfo->release_cmd(cmd);
2603                 ret = 1;
2604         }
2605         return ret;
2606 }
2607 EXPORT_SYMBOL(transport_generic_free_cmd);
2608
2609 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2610  * @se_cmd:     command descriptor to add
2611  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2612  */
2613 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2614 {
2615         struct se_session *se_sess = se_cmd->se_sess;
2616         unsigned long flags;
2617         int ret = 0;
2618
2619         /*
2620          * Add a second kref if the fabric caller is expecting to handle
2621          * fabric acknowledgement that requires two target_put_sess_cmd()
2622          * invocations before se_cmd descriptor release.
2623          */
2624         if (ack_kref) {
2625                 if (!kref_get_unless_zero(&se_cmd->cmd_kref))
2626                         return -EINVAL;
2627
2628                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2629         }
2630
2631         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2632         if (se_sess->sess_tearing_down) {
2633                 ret = -ESHUTDOWN;
2634                 goto out;
2635         }
2636         se_cmd->transport_state |= CMD_T_PRE_EXECUTE;
2637         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2638 out:
2639         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2640
2641         if (ret && ack_kref)
2642                 target_put_sess_cmd(se_cmd);
2643
2644         return ret;
2645 }
2646 EXPORT_SYMBOL(target_get_sess_cmd);
2647
2648 static void target_free_cmd_mem(struct se_cmd *cmd)
2649 {
2650         transport_free_pages(cmd);
2651
2652         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2653                 core_tmr_release_req(cmd->se_tmr_req);
2654         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2655                 kfree(cmd->t_task_cdb);
2656 }
2657
2658 static void target_release_cmd_kref(struct kref *kref)
2659 {
2660         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2661         struct se_session *se_sess = se_cmd->se_sess;
2662         unsigned long flags;
2663         bool fabric_stop;
2664
2665         if (se_sess) {
2666                 spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2667
2668                 spin_lock(&se_cmd->t_state_lock);
2669                 fabric_stop = (se_cmd->transport_state & CMD_T_FABRIC_STOP) &&
2670                               (se_cmd->transport_state & CMD_T_ABORTED);
2671                 spin_unlock(&se_cmd->t_state_lock);
2672
2673                 if (se_cmd->cmd_wait_set || fabric_stop) {
2674                         list_del_init(&se_cmd->se_cmd_list);
2675                         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2676                         target_free_cmd_mem(se_cmd);
2677                         complete(&se_cmd->cmd_wait_comp);
2678                         return;
2679                 }
2680                 list_del_init(&se_cmd->se_cmd_list);
2681                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2682         }
2683
2684         target_free_cmd_mem(se_cmd);
2685         se_cmd->se_tfo->release_cmd(se_cmd);
2686 }
2687
2688 /**
2689  * target_put_sess_cmd - decrease the command reference count
2690  * @se_cmd:     command to drop a reference from
2691  *
2692  * Returns 1 if and only if this target_put_sess_cmd() call caused the
2693  * refcount to drop to zero. Returns zero otherwise.
2694  */
2695 int target_put_sess_cmd(struct se_cmd *se_cmd)
2696 {
2697         return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2698 }
2699 EXPORT_SYMBOL(target_put_sess_cmd);
2700
2701 static const char *data_dir_name(enum dma_data_direction d)
2702 {
2703         switch (d) {
2704         case DMA_BIDIRECTIONAL: return "BIDI";
2705         case DMA_TO_DEVICE:     return "WRITE";
2706         case DMA_FROM_DEVICE:   return "READ";
2707         case DMA_NONE:          return "NONE";
2708         }
2709
2710         return "(?)";
2711 }
2712
2713 static const char *cmd_state_name(enum transport_state_table t)
2714 {
2715         switch (t) {
2716         case TRANSPORT_NO_STATE:        return "NO_STATE";
2717         case TRANSPORT_NEW_CMD:         return "NEW_CMD";
2718         case TRANSPORT_WRITE_PENDING:   return "WRITE_PENDING";
2719         case TRANSPORT_PROCESSING:      return "PROCESSING";
2720         case TRANSPORT_COMPLETE:        return "COMPLETE";
2721         case TRANSPORT_ISTATE_PROCESSING:
2722                                         return "ISTATE_PROCESSING";
2723         case TRANSPORT_COMPLETE_QF_WP:  return "COMPLETE_QF_WP";
2724         case TRANSPORT_COMPLETE_QF_OK:  return "COMPLETE_QF_OK";
2725         case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR";
2726         }
2727
2728         return "(?)";
2729 }
2730
2731 static void target_append_str(char **str, const char *txt)
2732 {
2733         char *prev = *str;
2734
2735         *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
2736                 kstrdup(txt, GFP_ATOMIC);
2737         kfree(prev);
2738 }
2739
2740 /*
2741  * Convert a transport state bitmask into a string. The caller is
2742  * responsible for freeing the returned pointer.
2743  */
2744 static char *target_ts_to_str(u32 ts)
2745 {
2746         char *str = NULL;
2747
2748         if (ts & CMD_T_ABORTED)
2749                 target_append_str(&str, "aborted");
2750         if (ts & CMD_T_ACTIVE)
2751                 target_append_str(&str, "active");
2752         if (ts & CMD_T_COMPLETE)
2753                 target_append_str(&str, "complete");
2754         if (ts & CMD_T_SENT)
2755                 target_append_str(&str, "sent");
2756         if (ts & CMD_T_STOP)
2757                 target_append_str(&str, "stop");
2758         if (ts & CMD_T_FABRIC_STOP)
2759                 target_append_str(&str, "fabric_stop");
2760
2761         return str;
2762 }
2763
2764 static const char *target_tmf_name(enum tcm_tmreq_table tmf)
2765 {
2766         switch (tmf) {
2767         case TMR_ABORT_TASK:            return "ABORT_TASK";
2768         case TMR_ABORT_TASK_SET:        return "ABORT_TASK_SET";
2769         case TMR_CLEAR_ACA:             return "CLEAR_ACA";
2770         case TMR_CLEAR_TASK_SET:        return "CLEAR_TASK_SET";
2771         case TMR_LUN_RESET:             return "LUN_RESET";
2772         case TMR_TARGET_WARM_RESET:     return "TARGET_WARM_RESET";
2773         case TMR_TARGET_COLD_RESET:     return "TARGET_COLD_RESET";
2774         case TMR_UNKNOWN:               break;
2775         }
2776         return "(?)";
2777 }
2778
2779 void target_show_cmd(const char *pfx, struct se_cmd *cmd)
2780 {
2781         char *ts_str = target_ts_to_str(cmd->transport_state);
2782         const u8 *cdb = cmd->t_task_cdb;
2783         struct se_tmr_req *tmf = cmd->se_tmr_req;
2784
2785         if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2786                 pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
2787                          pfx, cdb[0], cdb[1], cmd->tag,
2788                          data_dir_name(cmd->data_direction),
2789                          cmd->se_tfo->get_cmd_state(cmd),
2790                          cmd_state_name(cmd->t_state), cmd->data_length,
2791                          kref_read(&cmd->cmd_kref), ts_str);
2792         } else {
2793                 pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
2794                          pfx, target_tmf_name(tmf->function), cmd->tag,
2795                          tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
2796                          cmd_state_name(cmd->t_state),
2797                          kref_read(&cmd->cmd_kref), ts_str);
2798         }
2799         kfree(ts_str);
2800 }
2801 EXPORT_SYMBOL(target_show_cmd);
2802
2803 /* target_sess_cmd_list_set_waiting - Flag all commands in
2804  *         sess_cmd_list to complete cmd_wait_comp.  Set
2805  *         sess_tearing_down so no more commands are queued.
2806  * @se_sess:    session to flag
2807  */
2808 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2809 {
2810         struct se_cmd *se_cmd, *tmp_cmd;
2811         unsigned long flags;
2812         int rc;
2813
2814         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2815         if (se_sess->sess_tearing_down) {
2816                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2817                 return;
2818         }
2819         se_sess->sess_tearing_down = 1;
2820         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2821
2822         list_for_each_entry_safe(se_cmd, tmp_cmd,
2823                                  &se_sess->sess_wait_list, se_cmd_list) {
2824                 rc = kref_get_unless_zero(&se_cmd->cmd_kref);
2825                 if (rc) {
2826                         se_cmd->cmd_wait_set = 1;
2827                         spin_lock(&se_cmd->t_state_lock);
2828                         se_cmd->transport_state |= CMD_T_FABRIC_STOP;
2829                         spin_unlock(&se_cmd->t_state_lock);
2830                 } else
2831                         list_del_init(&se_cmd->se_cmd_list);
2832         }
2833
2834         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2835 }
2836 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2837
2838 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2839  * @se_sess:    session to wait for active I/O
2840  */
2841 void target_wait_for_sess_cmds(struct se_session *se_sess)
2842 {
2843         struct se_cmd *se_cmd, *tmp_cmd;
2844         unsigned long flags;
2845         bool tas;
2846
2847         list_for_each_entry_safe(se_cmd, tmp_cmd,
2848                                 &se_sess->sess_wait_list, se_cmd_list) {
2849                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2850                         " %d\n", se_cmd, se_cmd->t_state,
2851                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2852
2853                 spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2854                 tas = (se_cmd->transport_state & CMD_T_TAS);
2855                 spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2856
2857                 if (!target_put_sess_cmd(se_cmd)) {
2858                         if (tas)
2859                                 target_put_sess_cmd(se_cmd);
2860                 }
2861
2862                 wait_for_completion(&se_cmd->cmd_wait_comp);
2863                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2864                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2865                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2866
2867                 se_cmd->se_tfo->release_cmd(se_cmd);
2868         }
2869
2870         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2871         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2872         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2873
2874 }
2875 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2876
2877 static void target_lun_confirm(struct percpu_ref *ref)
2878 {
2879         struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
2880
2881         complete(&lun->lun_ref_comp);
2882 }
2883
2884 void transport_clear_lun_ref(struct se_lun *lun)
2885 {
2886         /*
2887          * Mark the percpu-ref as DEAD, switch to atomic_t mode, drop
2888          * the initial reference and schedule confirm kill to be
2889          * executed after one full RCU grace period has completed.
2890          */
2891         percpu_ref_kill_and_confirm(&lun->lun_ref, target_lun_confirm);
2892         /*
2893          * The first completion waits for percpu_ref_switch_to_atomic_rcu()
2894          * to call target_lun_confirm after lun->lun_ref has been marked
2895          * as __PERCPU_REF_DEAD on all CPUs, and switches to atomic_t
2896          * mode so that percpu_ref_tryget_live() lookup of lun->lun_ref
2897          * fails for all new incoming I/O.
2898          */
2899         wait_for_completion(&lun->lun_ref_comp);
2900         /*
2901          * The second completion waits for percpu_ref_put_many() to
2902          * invoke ->release() after lun->lun_ref has switched to
2903          * atomic_t mode, and lun->lun_ref.count has reached zero.
2904          *
2905          * At this point all target-core lun->lun_ref references have
2906          * been dropped via transport_lun_remove_cmd(), and it's safe
2907          * to proceed with the remaining LUN shutdown.
2908          */
2909         wait_for_completion(&lun->lun_shutdown_comp);
2910 }
2911
2912 static bool
2913 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2914                            bool *aborted, bool *tas, unsigned long *flags)
2915         __releases(&cmd->t_state_lock)
2916         __acquires(&cmd->t_state_lock)
2917 {
2918
2919         assert_spin_locked(&cmd->t_state_lock);
2920         WARN_ON_ONCE(!irqs_disabled());
2921
2922         if (fabric_stop)
2923                 cmd->transport_state |= CMD_T_FABRIC_STOP;
2924
2925         if (cmd->transport_state & CMD_T_ABORTED)
2926                 *aborted = true;
2927
2928         if (cmd->transport_state & CMD_T_TAS)
2929                 *tas = true;
2930
2931         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2932             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2933                 return false;
2934
2935         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2936             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2937                 return false;
2938
2939         if (!(cmd->transport_state & CMD_T_ACTIVE))
2940                 return false;
2941
2942         if (fabric_stop && *aborted)
2943                 return false;
2944
2945         cmd->transport_state |= CMD_T_STOP;
2946
2947         target_show_cmd("wait_for_tasks: Stopping ", cmd);
2948
2949         spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2950
2951         while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
2952                                             180 * HZ))
2953                 target_show_cmd("wait for tasks: ", cmd);
2954
2955         spin_lock_irqsave(&cmd->t_state_lock, *flags);
2956         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2957
2958         pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
2959                  "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
2960
2961         return true;
2962 }
2963
2964 /**
2965  * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
2966  * @cmd: command to wait on
2967  */
2968 bool transport_wait_for_tasks(struct se_cmd *cmd)
2969 {
2970         unsigned long flags;
2971         bool ret, aborted = false, tas = false;
2972
2973         spin_lock_irqsave(&cmd->t_state_lock, flags);
2974         ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
2975         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2976
2977         return ret;
2978 }
2979 EXPORT_SYMBOL(transport_wait_for_tasks);
2980
2981 struct sense_info {
2982         u8 key;
2983         u8 asc;
2984         u8 ascq;
2985         bool add_sector_info;
2986 };
2987
2988 static const struct sense_info sense_info_table[] = {
2989         [TCM_NO_SENSE] = {
2990                 .key = NOT_READY
2991         },
2992         [TCM_NON_EXISTENT_LUN] = {
2993                 .key = ILLEGAL_REQUEST,
2994                 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
2995         },
2996         [TCM_UNSUPPORTED_SCSI_OPCODE] = {
2997                 .key = ILLEGAL_REQUEST,
2998                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2999         },
3000         [TCM_SECTOR_COUNT_TOO_MANY] = {
3001                 .key = ILLEGAL_REQUEST,
3002                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3003         },
3004         [TCM_UNKNOWN_MODE_PAGE] = {
3005                 .key = ILLEGAL_REQUEST,
3006                 .asc = 0x24, /* INVALID FIELD IN CDB */
3007         },
3008         [TCM_CHECK_CONDITION_ABORT_CMD] = {
3009                 .key = ABORTED_COMMAND,
3010                 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3011                 .ascq = 0x03,
3012         },
3013         [TCM_INCORRECT_AMOUNT_OF_DATA] = {
3014                 .key = ABORTED_COMMAND,
3015                 .asc = 0x0c, /* WRITE ERROR */
3016                 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3017         },
3018         [TCM_INVALID_CDB_FIELD] = {
3019                 .key = ILLEGAL_REQUEST,
3020                 .asc = 0x24, /* INVALID FIELD IN CDB */
3021         },
3022         [TCM_INVALID_PARAMETER_LIST] = {
3023                 .key = ILLEGAL_REQUEST,
3024                 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3025         },
3026         [TCM_TOO_MANY_TARGET_DESCS] = {
3027                 .key = ILLEGAL_REQUEST,
3028                 .asc = 0x26,
3029                 .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3030         },
3031         [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3032                 .key = ILLEGAL_REQUEST,
3033                 .asc = 0x26,
3034                 .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3035         },
3036         [TCM_TOO_MANY_SEGMENT_DESCS] = {
3037                 .key = ILLEGAL_REQUEST,
3038                 .asc = 0x26,
3039                 .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3040         },
3041         [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3042                 .key = ILLEGAL_REQUEST,
3043                 .asc = 0x26,
3044                 .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3045         },
3046         [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3047                 .key = ILLEGAL_REQUEST,
3048                 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3049         },
3050         [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3051                 .key = ILLEGAL_REQUEST,
3052                 .asc = 0x0c, /* WRITE ERROR */
3053                 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3054         },
3055         [TCM_SERVICE_CRC_ERROR] = {
3056                 .key = ABORTED_COMMAND,
3057                 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3058                 .ascq = 0x05, /* N/A */
3059         },
3060         [TCM_SNACK_REJECTED] = {
3061                 .key = ABORTED_COMMAND,
3062                 .asc = 0x11, /* READ ERROR */
3063                 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3064         },
3065         [TCM_WRITE_PROTECTED] = {
3066                 .key = DATA_PROTECT,
3067                 .asc = 0x27, /* WRITE PROTECTED */
3068         },
3069         [TCM_ADDRESS_OUT_OF_RANGE] = {
3070                 .key = ILLEGAL_REQUEST,
3071                 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3072         },
3073         [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3074                 .key = UNIT_ATTENTION,
3075         },
3076         [TCM_CHECK_CONDITION_NOT_READY] = {
3077                 .key = NOT_READY,
3078         },
3079         [TCM_MISCOMPARE_VERIFY] = {
3080                 .key = MISCOMPARE,
3081                 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3082                 .ascq = 0x00,
3083         },
3084         [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
3085                 .key = ABORTED_COMMAND,
3086                 .asc = 0x10,
3087                 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
3088                 .add_sector_info = true,
3089         },
3090         [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
3091                 .key = ABORTED_COMMAND,
3092                 .asc = 0x10,
3093                 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
3094                 .add_sector_info = true,
3095         },
3096         [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
3097                 .key = ABORTED_COMMAND,
3098                 .asc = 0x10,
3099                 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
3100                 .add_sector_info = true,
3101         },
3102         [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
3103                 .key = COPY_ABORTED,
3104                 .asc = 0x0d,
3105                 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
3106
3107         },
3108         [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
3109                 /*
3110                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
3111                  * Solaris initiators.  Returning NOT READY instead means the
3112                  * operations will be retried a finite number of times and we
3113                  * can survive intermittent errors.
3114                  */
3115                 .key = NOT_READY,
3116                 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
3117         },
3118         [TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
3119                 /*
3120                  * From spc4r22 section5.7.7,5.7.8
3121                  * If a PERSISTENT RESERVE OUT command with a REGISTER service action
3122                  * or a REGISTER AND IGNORE EXISTING KEY service action or
3123                  * REGISTER AND MOVE service actionis attempted,
3124                  * but there are insufficient device server resources to complete the
3125                  * operation, then the command shall be terminated with CHECK CONDITION
3126                  * status, with the sense key set to ILLEGAL REQUEST,and the additonal
3127                  * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
3128                  */
3129                 .key = ILLEGAL_REQUEST,
3130                 .asc = 0x55,
3131                 .ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
3132         },
3133 };
3134
3135 static int translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
3136 {
3137         const struct sense_info *si;
3138         u8 *buffer = cmd->sense_buffer;
3139         int r = (__force int)reason;
3140         u8 asc, ascq;
3141         bool desc_format = target_sense_desc_format(cmd->se_dev);
3142
3143         if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
3144                 si = &sense_info_table[r];
3145         else
3146                 si = &sense_info_table[(__force int)
3147                                        TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3148
3149         if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
3150                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
3151                 WARN_ON_ONCE(asc == 0);
3152         } else if (si->asc == 0) {
3153                 WARN_ON_ONCE(cmd->scsi_asc == 0);
3154                 asc = cmd->scsi_asc;
3155                 ascq = cmd->scsi_ascq;
3156         } else {
3157                 asc = si->asc;
3158                 ascq = si->ascq;
3159         }
3160
3161         scsi_build_sense_buffer(desc_format, buffer, si->key, asc, ascq);
3162         if (si->add_sector_info)
3163                 return scsi_set_sense_information(buffer,
3164                                                   cmd->scsi_sense_length,
3165                                                   cmd->bad_sector);
3166
3167         return 0;
3168 }
3169
3170 int
3171 transport_send_check_condition_and_sense(struct se_cmd *cmd,
3172                 sense_reason_t reason, int from_transport)
3173 {
3174         unsigned long flags;
3175
3176         spin_lock_irqsave(&cmd->t_state_lock, flags);
3177         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
3178                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3179                 return 0;
3180         }
3181         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
3182         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3183
3184         if (!from_transport) {
3185                 int rc;
3186
3187                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
3188                 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
3189                 cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
3190                 rc = translate_sense_reason(cmd, reason);
3191                 if (rc)
3192                         return rc;
3193         }
3194
3195         trace_target_cmd_complete(cmd);
3196         return cmd->se_tfo->queue_status(cmd);
3197 }
3198 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
3199
3200 static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
3201         __releases(&cmd->t_state_lock)
3202         __acquires(&cmd->t_state_lock)
3203 {
3204         int ret;
3205
3206         assert_spin_locked(&cmd->t_state_lock);
3207         WARN_ON_ONCE(!irqs_disabled());
3208
3209         if (!(cmd->transport_state & CMD_T_ABORTED))
3210                 return 0;
3211         /*
3212          * If cmd has been aborted but either no status is to be sent or it has
3213          * already been sent, just return
3214          */
3215         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
3216                 if (send_status)
3217                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3218                 return 1;
3219         }
3220
3221         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
3222                 " 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);
3223
3224         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
3225         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3226         trace_target_cmd_complete(cmd);
3227