target: Fix Task Aborted Status (TAS) handling
[firefly-linux-kernel-4.4.55.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 <asm/unaligned.h>
38 #include <net/sock.h>
39 #include <net/tcp.h>
40 #include <scsi/scsi.h>
41 #include <scsi/scsi_cmnd.h>
42 #include <scsi/scsi_tcq.h>
43
44 #include <target/target_core_base.h>
45 #include <target/target_core_backend.h>
46 #include <target/target_core_fabric.h>
47 #include <target/target_core_configfs.h>
48
49 #include "target_core_internal.h"
50 #include "target_core_alua.h"
51 #include "target_core_pr.h"
52 #include "target_core_ua.h"
53
54 #define CREATE_TRACE_POINTS
55 #include <trace/events/target.h>
56
57 static struct workqueue_struct *target_completion_wq;
58 static struct kmem_cache *se_sess_cache;
59 struct kmem_cache *se_ua_cache;
60 struct kmem_cache *t10_pr_reg_cache;
61 struct kmem_cache *t10_alua_lu_gp_cache;
62 struct kmem_cache *t10_alua_lu_gp_mem_cache;
63 struct kmem_cache *t10_alua_tg_pt_gp_cache;
64 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
65 struct kmem_cache *t10_alua_lba_map_cache;
66 struct kmem_cache *t10_alua_lba_map_mem_cache;
67
68 static void transport_complete_task_attr(struct se_cmd *cmd);
69 static void transport_handle_queue_full(struct se_cmd *cmd,
70                 struct se_device *dev);
71 static int transport_put_cmd(struct se_cmd *cmd);
72 static void target_complete_ok_work(struct work_struct *work);
73
74 int init_se_kmem_caches(void)
75 {
76         se_sess_cache = kmem_cache_create("se_sess_cache",
77                         sizeof(struct se_session), __alignof__(struct se_session),
78                         0, NULL);
79         if (!se_sess_cache) {
80                 pr_err("kmem_cache_create() for struct se_session"
81                                 " failed\n");
82                 goto out;
83         }
84         se_ua_cache = kmem_cache_create("se_ua_cache",
85                         sizeof(struct se_ua), __alignof__(struct se_ua),
86                         0, NULL);
87         if (!se_ua_cache) {
88                 pr_err("kmem_cache_create() for struct se_ua failed\n");
89                 goto out_free_sess_cache;
90         }
91         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
92                         sizeof(struct t10_pr_registration),
93                         __alignof__(struct t10_pr_registration), 0, NULL);
94         if (!t10_pr_reg_cache) {
95                 pr_err("kmem_cache_create() for struct t10_pr_registration"
96                                 " failed\n");
97                 goto out_free_ua_cache;
98         }
99         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
100                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
101                         0, NULL);
102         if (!t10_alua_lu_gp_cache) {
103                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
104                                 " failed\n");
105                 goto out_free_pr_reg_cache;
106         }
107         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
108                         sizeof(struct t10_alua_lu_gp_member),
109                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
110         if (!t10_alua_lu_gp_mem_cache) {
111                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
112                                 "cache failed\n");
113                 goto out_free_lu_gp_cache;
114         }
115         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
116                         sizeof(struct t10_alua_tg_pt_gp),
117                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
118         if (!t10_alua_tg_pt_gp_cache) {
119                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
120                                 "cache failed\n");
121                 goto out_free_lu_gp_mem_cache;
122         }
123         t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
124                         "t10_alua_tg_pt_gp_mem_cache",
125                         sizeof(struct t10_alua_tg_pt_gp_member),
126                         __alignof__(struct t10_alua_tg_pt_gp_member),
127                         0, NULL);
128         if (!t10_alua_tg_pt_gp_mem_cache) {
129                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
130                                 "mem_t failed\n");
131                 goto out_free_tg_pt_gp_cache;
132         }
133         t10_alua_lba_map_cache = kmem_cache_create(
134                         "t10_alua_lba_map_cache",
135                         sizeof(struct t10_alua_lba_map),
136                         __alignof__(struct t10_alua_lba_map), 0, NULL);
137         if (!t10_alua_lba_map_cache) {
138                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
139                                 "cache failed\n");
140                 goto out_free_tg_pt_gp_mem_cache;
141         }
142         t10_alua_lba_map_mem_cache = kmem_cache_create(
143                         "t10_alua_lba_map_mem_cache",
144                         sizeof(struct t10_alua_lba_map_member),
145                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
146         if (!t10_alua_lba_map_mem_cache) {
147                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
148                                 "cache failed\n");
149                 goto out_free_lba_map_cache;
150         }
151
152         target_completion_wq = alloc_workqueue("target_completion",
153                                                WQ_MEM_RECLAIM, 0);
154         if (!target_completion_wq)
155                 goto out_free_lba_map_mem_cache;
156
157         return 0;
158
159 out_free_lba_map_mem_cache:
160         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
161 out_free_lba_map_cache:
162         kmem_cache_destroy(t10_alua_lba_map_cache);
163 out_free_tg_pt_gp_mem_cache:
164         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
165 out_free_tg_pt_gp_cache:
166         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
167 out_free_lu_gp_mem_cache:
168         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
169 out_free_lu_gp_cache:
170         kmem_cache_destroy(t10_alua_lu_gp_cache);
171 out_free_pr_reg_cache:
172         kmem_cache_destroy(t10_pr_reg_cache);
173 out_free_ua_cache:
174         kmem_cache_destroy(se_ua_cache);
175 out_free_sess_cache:
176         kmem_cache_destroy(se_sess_cache);
177 out:
178         return -ENOMEM;
179 }
180
181 void release_se_kmem_caches(void)
182 {
183         destroy_workqueue(target_completion_wq);
184         kmem_cache_destroy(se_sess_cache);
185         kmem_cache_destroy(se_ua_cache);
186         kmem_cache_destroy(t10_pr_reg_cache);
187         kmem_cache_destroy(t10_alua_lu_gp_cache);
188         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
189         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
190         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
191         kmem_cache_destroy(t10_alua_lba_map_cache);
192         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
193 }
194
195 /* This code ensures unique mib indexes are handed out. */
196 static DEFINE_SPINLOCK(scsi_mib_index_lock);
197 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
198
199 /*
200  * Allocate a new row index for the entry type specified
201  */
202 u32 scsi_get_new_index(scsi_index_t type)
203 {
204         u32 new_index;
205
206         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
207
208         spin_lock(&scsi_mib_index_lock);
209         new_index = ++scsi_mib_index[type];
210         spin_unlock(&scsi_mib_index_lock);
211
212         return new_index;
213 }
214
215 void transport_subsystem_check_init(void)
216 {
217         int ret;
218         static int sub_api_initialized;
219
220         if (sub_api_initialized)
221                 return;
222
223         ret = request_module("target_core_iblock");
224         if (ret != 0)
225                 pr_err("Unable to load target_core_iblock\n");
226
227         ret = request_module("target_core_file");
228         if (ret != 0)
229                 pr_err("Unable to load target_core_file\n");
230
231         ret = request_module("target_core_pscsi");
232         if (ret != 0)
233                 pr_err("Unable to load target_core_pscsi\n");
234
235         sub_api_initialized = 1;
236 }
237
238 struct se_session *transport_init_session(void)
239 {
240         struct se_session *se_sess;
241
242         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
243         if (!se_sess) {
244                 pr_err("Unable to allocate struct se_session from"
245                                 " se_sess_cache\n");
246                 return ERR_PTR(-ENOMEM);
247         }
248         INIT_LIST_HEAD(&se_sess->sess_list);
249         INIT_LIST_HEAD(&se_sess->sess_acl_list);
250         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
251         INIT_LIST_HEAD(&se_sess->sess_wait_list);
252         spin_lock_init(&se_sess->sess_cmd_lock);
253         kref_init(&se_sess->sess_kref);
254
255         return se_sess;
256 }
257 EXPORT_SYMBOL(transport_init_session);
258
259 int transport_alloc_session_tags(struct se_session *se_sess,
260                                  unsigned int tag_num, unsigned int tag_size)
261 {
262         int rc;
263
264         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
265                                         GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
266         if (!se_sess->sess_cmd_map) {
267                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
268                 if (!se_sess->sess_cmd_map) {
269                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
270                         return -ENOMEM;
271                 }
272         }
273
274         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
275         if (rc < 0) {
276                 pr_err("Unable to init se_sess->sess_tag_pool,"
277                         " tag_num: %u\n", tag_num);
278                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
279                         vfree(se_sess->sess_cmd_map);
280                 else
281                         kfree(se_sess->sess_cmd_map);
282                 se_sess->sess_cmd_map = NULL;
283                 return -ENOMEM;
284         }
285
286         return 0;
287 }
288 EXPORT_SYMBOL(transport_alloc_session_tags);
289
290 struct se_session *transport_init_session_tags(unsigned int tag_num,
291                                                unsigned int tag_size)
292 {
293         struct se_session *se_sess;
294         int rc;
295
296         se_sess = transport_init_session();
297         if (IS_ERR(se_sess))
298                 return se_sess;
299
300         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
301         if (rc < 0) {
302                 transport_free_session(se_sess);
303                 return ERR_PTR(-ENOMEM);
304         }
305
306         return se_sess;
307 }
308 EXPORT_SYMBOL(transport_init_session_tags);
309
310 /*
311  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
312  */
313 void __transport_register_session(
314         struct se_portal_group *se_tpg,
315         struct se_node_acl *se_nacl,
316         struct se_session *se_sess,
317         void *fabric_sess_ptr)
318 {
319         unsigned char buf[PR_REG_ISID_LEN];
320
321         se_sess->se_tpg = se_tpg;
322         se_sess->fabric_sess_ptr = fabric_sess_ptr;
323         /*
324          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
325          *
326          * Only set for struct se_session's that will actually be moving I/O.
327          * eg: *NOT* discovery sessions.
328          */
329         if (se_nacl) {
330                 /*
331                  * If the fabric module supports an ISID based TransportID,
332                  * save this value in binary from the fabric I_T Nexus now.
333                  */
334                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
335                         memset(&buf[0], 0, PR_REG_ISID_LEN);
336                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
337                                         &buf[0], PR_REG_ISID_LEN);
338                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
339                 }
340                 kref_get(&se_nacl->acl_kref);
341
342                 spin_lock_irq(&se_nacl->nacl_sess_lock);
343                 /*
344                  * The se_nacl->nacl_sess pointer will be set to the
345                  * last active I_T Nexus for each struct se_node_acl.
346                  */
347                 se_nacl->nacl_sess = se_sess;
348
349                 list_add_tail(&se_sess->sess_acl_list,
350                               &se_nacl->acl_sess_list);
351                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
352         }
353         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
354
355         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
356                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
357 }
358 EXPORT_SYMBOL(__transport_register_session);
359
360 void transport_register_session(
361         struct se_portal_group *se_tpg,
362         struct se_node_acl *se_nacl,
363         struct se_session *se_sess,
364         void *fabric_sess_ptr)
365 {
366         unsigned long flags;
367
368         spin_lock_irqsave(&se_tpg->session_lock, flags);
369         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
370         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
371 }
372 EXPORT_SYMBOL(transport_register_session);
373
374 static void target_release_session(struct kref *kref)
375 {
376         struct se_session *se_sess = container_of(kref,
377                         struct se_session, sess_kref);
378         struct se_portal_group *se_tpg = se_sess->se_tpg;
379
380         se_tpg->se_tpg_tfo->close_session(se_sess);
381 }
382
383 void target_get_session(struct se_session *se_sess)
384 {
385         kref_get(&se_sess->sess_kref);
386 }
387 EXPORT_SYMBOL(target_get_session);
388
389 void target_put_session(struct se_session *se_sess)
390 {
391         struct se_portal_group *tpg = se_sess->se_tpg;
392
393         if (tpg->se_tpg_tfo->put_session != NULL) {
394                 tpg->se_tpg_tfo->put_session(se_sess);
395                 return;
396         }
397         kref_put(&se_sess->sess_kref, target_release_session);
398 }
399 EXPORT_SYMBOL(target_put_session);
400
401 static void target_complete_nacl(struct kref *kref)
402 {
403         struct se_node_acl *nacl = container_of(kref,
404                                 struct se_node_acl, acl_kref);
405
406         complete(&nacl->acl_free_comp);
407 }
408
409 void target_put_nacl(struct se_node_acl *nacl)
410 {
411         kref_put(&nacl->acl_kref, target_complete_nacl);
412 }
413
414 void transport_deregister_session_configfs(struct se_session *se_sess)
415 {
416         struct se_node_acl *se_nacl;
417         unsigned long flags;
418         /*
419          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
420          */
421         se_nacl = se_sess->se_node_acl;
422         if (se_nacl) {
423                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
424                 if (se_nacl->acl_stop == 0)
425                         list_del(&se_sess->sess_acl_list);
426                 /*
427                  * If the session list is empty, then clear the pointer.
428                  * Otherwise, set the struct se_session pointer from the tail
429                  * element of the per struct se_node_acl active session list.
430                  */
431                 if (list_empty(&se_nacl->acl_sess_list))
432                         se_nacl->nacl_sess = NULL;
433                 else {
434                         se_nacl->nacl_sess = container_of(
435                                         se_nacl->acl_sess_list.prev,
436                                         struct se_session, sess_acl_list);
437                 }
438                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
439         }
440 }
441 EXPORT_SYMBOL(transport_deregister_session_configfs);
442
443 void transport_free_session(struct se_session *se_sess)
444 {
445         if (se_sess->sess_cmd_map) {
446                 percpu_ida_destroy(&se_sess->sess_tag_pool);
447                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
448                         vfree(se_sess->sess_cmd_map);
449                 else
450                         kfree(se_sess->sess_cmd_map);
451         }
452         kmem_cache_free(se_sess_cache, se_sess);
453 }
454 EXPORT_SYMBOL(transport_free_session);
455
456 void transport_deregister_session(struct se_session *se_sess)
457 {
458         struct se_portal_group *se_tpg = se_sess->se_tpg;
459         struct target_core_fabric_ops *se_tfo;
460         struct se_node_acl *se_nacl;
461         unsigned long flags;
462         bool comp_nacl = true;
463
464         if (!se_tpg) {
465                 transport_free_session(se_sess);
466                 return;
467         }
468         se_tfo = se_tpg->se_tpg_tfo;
469
470         spin_lock_irqsave(&se_tpg->session_lock, flags);
471         list_del(&se_sess->sess_list);
472         se_sess->se_tpg = NULL;
473         se_sess->fabric_sess_ptr = NULL;
474         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
475
476         /*
477          * Determine if we need to do extra work for this initiator node's
478          * struct se_node_acl if it had been previously dynamically generated.
479          */
480         se_nacl = se_sess->se_node_acl;
481
482         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
483         if (se_nacl && se_nacl->dynamic_node_acl) {
484                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
485                         list_del(&se_nacl->acl_list);
486                         se_tpg->num_node_acls--;
487                         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
488                         core_tpg_wait_for_nacl_pr_ref(se_nacl);
489                         core_free_device_list_for_node(se_nacl, se_tpg);
490                         se_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
491
492                         comp_nacl = false;
493                         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
494                 }
495         }
496         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
497
498         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
499                 se_tpg->se_tpg_tfo->get_fabric_name());
500         /*
501          * If last kref is dropping now for an explicit NodeACL, awake sleeping
502          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
503          * removal context.
504          */
505         if (se_nacl && comp_nacl == true)
506                 target_put_nacl(se_nacl);
507
508         transport_free_session(se_sess);
509 }
510 EXPORT_SYMBOL(transport_deregister_session);
511
512 /*
513  * Called with cmd->t_state_lock held.
514  */
515 static void target_remove_from_state_list(struct se_cmd *cmd)
516 {
517         struct se_device *dev = cmd->se_dev;
518         unsigned long flags;
519
520         if (!dev)
521                 return;
522
523         if (cmd->transport_state & CMD_T_BUSY)
524                 return;
525
526         spin_lock_irqsave(&dev->execute_task_lock, flags);
527         if (cmd->state_active) {
528                 list_del(&cmd->state_list);
529                 cmd->state_active = false;
530         }
531         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
532 }
533
534 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
535                                     bool write_pending)
536 {
537         unsigned long flags;
538
539         spin_lock_irqsave(&cmd->t_state_lock, flags);
540         if (write_pending)
541                 cmd->t_state = TRANSPORT_WRITE_PENDING;
542
543         if (remove_from_lists) {
544                 target_remove_from_state_list(cmd);
545
546                 /*
547                  * Clear struct se_cmd->se_lun before the handoff to FE.
548                  */
549                 cmd->se_lun = NULL;
550         }
551
552         /*
553          * Determine if frontend context caller is requesting the stopping of
554          * this command for frontend exceptions.
555          */
556         if (cmd->transport_state & CMD_T_STOP) {
557                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
558                         __func__, __LINE__,
559                         cmd->se_tfo->get_task_tag(cmd));
560
561                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
562
563                 complete(&cmd->t_transport_stop_comp);
564                 return 1;
565         }
566
567         cmd->transport_state &= ~CMD_T_ACTIVE;
568         if (remove_from_lists) {
569                 /*
570                  * Some fabric modules like tcm_loop can release
571                  * their internally allocated I/O reference now and
572                  * struct se_cmd now.
573                  *
574                  * Fabric modules are expected to return '1' here if the
575                  * se_cmd being passed is released at this point,
576                  * or zero if not being released.
577                  */
578                 if (cmd->se_tfo->check_stop_free != NULL) {
579                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
580                         return cmd->se_tfo->check_stop_free(cmd);
581                 }
582         }
583
584         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
585         return 0;
586 }
587
588 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
589 {
590         return transport_cmd_check_stop(cmd, true, false);
591 }
592
593 static void transport_lun_remove_cmd(struct se_cmd *cmd)
594 {
595         struct se_lun *lun = cmd->se_lun;
596
597         if (!lun)
598                 return;
599
600         if (cmpxchg(&cmd->lun_ref_active, true, false))
601                 percpu_ref_put(&lun->lun_ref);
602 }
603
604 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
605 {
606         if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
607                 transport_lun_remove_cmd(cmd);
608
609         if (transport_cmd_check_stop_to_fabric(cmd))
610                 return;
611         if (remove)
612                 transport_put_cmd(cmd);
613 }
614
615 static void target_complete_failure_work(struct work_struct *work)
616 {
617         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
618
619         transport_generic_request_failure(cmd,
620                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
621 }
622
623 /*
624  * Used when asking transport to copy Sense Data from the underlying
625  * Linux/SCSI struct scsi_cmnd
626  */
627 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
628 {
629         struct se_device *dev = cmd->se_dev;
630
631         WARN_ON(!cmd->se_lun);
632
633         if (!dev)
634                 return NULL;
635
636         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
637                 return NULL;
638
639         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
640
641         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
642                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
643         return cmd->sense_buffer;
644 }
645
646 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
647 {
648         struct se_device *dev = cmd->se_dev;
649         int success = scsi_status == GOOD;
650         unsigned long flags;
651
652         cmd->scsi_status = scsi_status;
653
654
655         spin_lock_irqsave(&cmd->t_state_lock, flags);
656         cmd->transport_state &= ~CMD_T_BUSY;
657
658         if (dev && dev->transport->transport_complete) {
659                 dev->transport->transport_complete(cmd,
660                                 cmd->t_data_sg,
661                                 transport_get_sense_buffer(cmd));
662                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
663                         success = 1;
664         }
665
666         /*
667          * See if we are waiting to complete for an exception condition.
668          */
669         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
670                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
671                 complete(&cmd->task_stop_comp);
672                 return;
673         }
674
675         /*
676          * Check for case where an explicit ABORT_TASK has been received
677          * and transport_wait_for_tasks() will be waiting for completion..
678          */
679         if (cmd->transport_state & CMD_T_ABORTED &&
680             cmd->transport_state & CMD_T_STOP) {
681                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
682                 complete(&cmd->t_transport_stop_comp);
683                 return;
684         } else if (!success) {
685                 INIT_WORK(&cmd->work, target_complete_failure_work);
686         } else {
687                 INIT_WORK(&cmd->work, target_complete_ok_work);
688         }
689
690         cmd->t_state = TRANSPORT_COMPLETE;
691         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
692         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
693
694         queue_work(target_completion_wq, &cmd->work);
695 }
696 EXPORT_SYMBOL(target_complete_cmd);
697
698 static void target_add_to_state_list(struct se_cmd *cmd)
699 {
700         struct se_device *dev = cmd->se_dev;
701         unsigned long flags;
702
703         spin_lock_irqsave(&dev->execute_task_lock, flags);
704         if (!cmd->state_active) {
705                 list_add_tail(&cmd->state_list, &dev->state_list);
706                 cmd->state_active = true;
707         }
708         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
709 }
710
711 /*
712  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
713  */
714 static void transport_write_pending_qf(struct se_cmd *cmd);
715 static void transport_complete_qf(struct se_cmd *cmd);
716
717 void target_qf_do_work(struct work_struct *work)
718 {
719         struct se_device *dev = container_of(work, struct se_device,
720                                         qf_work_queue);
721         LIST_HEAD(qf_cmd_list);
722         struct se_cmd *cmd, *cmd_tmp;
723
724         spin_lock_irq(&dev->qf_cmd_lock);
725         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
726         spin_unlock_irq(&dev->qf_cmd_lock);
727
728         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
729                 list_del(&cmd->se_qf_node);
730                 atomic_dec(&dev->dev_qf_count);
731                 smp_mb__after_atomic_dec();
732
733                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
734                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
735                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
736                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
737                         : "UNKNOWN");
738
739                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
740                         transport_write_pending_qf(cmd);
741                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
742                         transport_complete_qf(cmd);
743         }
744 }
745
746 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
747 {
748         switch (cmd->data_direction) {
749         case DMA_NONE:
750                 return "NONE";
751         case DMA_FROM_DEVICE:
752                 return "READ";
753         case DMA_TO_DEVICE:
754                 return "WRITE";
755         case DMA_BIDIRECTIONAL:
756                 return "BIDI";
757         default:
758                 break;
759         }
760
761         return "UNKNOWN";
762 }
763
764 void transport_dump_dev_state(
765         struct se_device *dev,
766         char *b,
767         int *bl)
768 {
769         *bl += sprintf(b + *bl, "Status: ");
770         if (dev->export_count)
771                 *bl += sprintf(b + *bl, "ACTIVATED");
772         else
773                 *bl += sprintf(b + *bl, "DEACTIVATED");
774
775         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
776         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
777                 dev->dev_attrib.block_size,
778                 dev->dev_attrib.hw_max_sectors);
779         *bl += sprintf(b + *bl, "        ");
780 }
781
782 void transport_dump_vpd_proto_id(
783         struct t10_vpd *vpd,
784         unsigned char *p_buf,
785         int p_buf_len)
786 {
787         unsigned char buf[VPD_TMP_BUF_SIZE];
788         int len;
789
790         memset(buf, 0, VPD_TMP_BUF_SIZE);
791         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
792
793         switch (vpd->protocol_identifier) {
794         case 0x00:
795                 sprintf(buf+len, "Fibre Channel\n");
796                 break;
797         case 0x10:
798                 sprintf(buf+len, "Parallel SCSI\n");
799                 break;
800         case 0x20:
801                 sprintf(buf+len, "SSA\n");
802                 break;
803         case 0x30:
804                 sprintf(buf+len, "IEEE 1394\n");
805                 break;
806         case 0x40:
807                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
808                                 " Protocol\n");
809                 break;
810         case 0x50:
811                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
812                 break;
813         case 0x60:
814                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
815                 break;
816         case 0x70:
817                 sprintf(buf+len, "Automation/Drive Interface Transport"
818                                 " Protocol\n");
819                 break;
820         case 0x80:
821                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
822                 break;
823         default:
824                 sprintf(buf+len, "Unknown 0x%02x\n",
825                                 vpd->protocol_identifier);
826                 break;
827         }
828
829         if (p_buf)
830                 strncpy(p_buf, buf, p_buf_len);
831         else
832                 pr_debug("%s", buf);
833 }
834
835 void
836 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
837 {
838         /*
839          * Check if the Protocol Identifier Valid (PIV) bit is set..
840          *
841          * from spc3r23.pdf section 7.5.1
842          */
843          if (page_83[1] & 0x80) {
844                 vpd->protocol_identifier = (page_83[0] & 0xf0);
845                 vpd->protocol_identifier_set = 1;
846                 transport_dump_vpd_proto_id(vpd, NULL, 0);
847         }
848 }
849 EXPORT_SYMBOL(transport_set_vpd_proto_id);
850
851 int transport_dump_vpd_assoc(
852         struct t10_vpd *vpd,
853         unsigned char *p_buf,
854         int p_buf_len)
855 {
856         unsigned char buf[VPD_TMP_BUF_SIZE];
857         int ret = 0;
858         int len;
859
860         memset(buf, 0, VPD_TMP_BUF_SIZE);
861         len = sprintf(buf, "T10 VPD Identifier Association: ");
862
863         switch (vpd->association) {
864         case 0x00:
865                 sprintf(buf+len, "addressed logical unit\n");
866                 break;
867         case 0x10:
868                 sprintf(buf+len, "target port\n");
869                 break;
870         case 0x20:
871                 sprintf(buf+len, "SCSI target device\n");
872                 break;
873         default:
874                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
875                 ret = -EINVAL;
876                 break;
877         }
878
879         if (p_buf)
880                 strncpy(p_buf, buf, p_buf_len);
881         else
882                 pr_debug("%s", buf);
883
884         return ret;
885 }
886
887 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
888 {
889         /*
890          * The VPD identification association..
891          *
892          * from spc3r23.pdf Section 7.6.3.1 Table 297
893          */
894         vpd->association = (page_83[1] & 0x30);
895         return transport_dump_vpd_assoc(vpd, NULL, 0);
896 }
897 EXPORT_SYMBOL(transport_set_vpd_assoc);
898
899 int transport_dump_vpd_ident_type(
900         struct t10_vpd *vpd,
901         unsigned char *p_buf,
902         int p_buf_len)
903 {
904         unsigned char buf[VPD_TMP_BUF_SIZE];
905         int ret = 0;
906         int len;
907
908         memset(buf, 0, VPD_TMP_BUF_SIZE);
909         len = sprintf(buf, "T10 VPD Identifier Type: ");
910
911         switch (vpd->device_identifier_type) {
912         case 0x00:
913                 sprintf(buf+len, "Vendor specific\n");
914                 break;
915         case 0x01:
916                 sprintf(buf+len, "T10 Vendor ID based\n");
917                 break;
918         case 0x02:
919                 sprintf(buf+len, "EUI-64 based\n");
920                 break;
921         case 0x03:
922                 sprintf(buf+len, "NAA\n");
923                 break;
924         case 0x04:
925                 sprintf(buf+len, "Relative target port identifier\n");
926                 break;
927         case 0x08:
928                 sprintf(buf+len, "SCSI name string\n");
929                 break;
930         default:
931                 sprintf(buf+len, "Unsupported: 0x%02x\n",
932                                 vpd->device_identifier_type);
933                 ret = -EINVAL;
934                 break;
935         }
936
937         if (p_buf) {
938                 if (p_buf_len < strlen(buf)+1)
939                         return -EINVAL;
940                 strncpy(p_buf, buf, p_buf_len);
941         } else {
942                 pr_debug("%s", buf);
943         }
944
945         return ret;
946 }
947
948 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
949 {
950         /*
951          * The VPD identifier type..
952          *
953          * from spc3r23.pdf Section 7.6.3.1 Table 298
954          */
955         vpd->device_identifier_type = (page_83[1] & 0x0f);
956         return transport_dump_vpd_ident_type(vpd, NULL, 0);
957 }
958 EXPORT_SYMBOL(transport_set_vpd_ident_type);
959
960 int transport_dump_vpd_ident(
961         struct t10_vpd *vpd,
962         unsigned char *p_buf,
963         int p_buf_len)
964 {
965         unsigned char buf[VPD_TMP_BUF_SIZE];
966         int ret = 0;
967
968         memset(buf, 0, VPD_TMP_BUF_SIZE);
969
970         switch (vpd->device_identifier_code_set) {
971         case 0x01: /* Binary */
972                 snprintf(buf, sizeof(buf),
973                         "T10 VPD Binary Device Identifier: %s\n",
974                         &vpd->device_identifier[0]);
975                 break;
976         case 0x02: /* ASCII */
977                 snprintf(buf, sizeof(buf),
978                         "T10 VPD ASCII Device Identifier: %s\n",
979                         &vpd->device_identifier[0]);
980                 break;
981         case 0x03: /* UTF-8 */
982                 snprintf(buf, sizeof(buf),
983                         "T10 VPD UTF-8 Device Identifier: %s\n",
984                         &vpd->device_identifier[0]);
985                 break;
986         default:
987                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
988                         " 0x%02x", vpd->device_identifier_code_set);
989                 ret = -EINVAL;
990                 break;
991         }
992
993         if (p_buf)
994                 strncpy(p_buf, buf, p_buf_len);
995         else
996                 pr_debug("%s", buf);
997
998         return ret;
999 }
1000
1001 int
1002 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1003 {
1004         static const char hex_str[] = "0123456789abcdef";
1005         int j = 0, i = 4; /* offset to start of the identifier */
1006
1007         /*
1008          * The VPD Code Set (encoding)
1009          *
1010          * from spc3r23.pdf Section 7.6.3.1 Table 296
1011          */
1012         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1013         switch (vpd->device_identifier_code_set) {
1014         case 0x01: /* Binary */
1015                 vpd->device_identifier[j++] =
1016                                 hex_str[vpd->device_identifier_type];
1017                 while (i < (4 + page_83[3])) {
1018                         vpd->device_identifier[j++] =
1019                                 hex_str[(page_83[i] & 0xf0) >> 4];
1020                         vpd->device_identifier[j++] =
1021                                 hex_str[page_83[i] & 0x0f];
1022                         i++;
1023                 }
1024                 break;
1025         case 0x02: /* ASCII */
1026         case 0x03: /* UTF-8 */
1027                 while (i < (4 + page_83[3]))
1028                         vpd->device_identifier[j++] = page_83[i++];
1029                 break;
1030         default:
1031                 break;
1032         }
1033
1034         return transport_dump_vpd_ident(vpd, NULL, 0);
1035 }
1036 EXPORT_SYMBOL(transport_set_vpd_ident);
1037
1038 sense_reason_t
1039 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1040 {
1041         struct se_device *dev = cmd->se_dev;
1042
1043         if (cmd->unknown_data_length) {
1044                 cmd->data_length = size;
1045         } else if (size != cmd->data_length) {
1046                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1047                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1048                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1049                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1050
1051                 if (cmd->data_direction == DMA_TO_DEVICE) {
1052                         pr_err("Rejecting underflow/overflow"
1053                                         " WRITE data\n");
1054                         return TCM_INVALID_CDB_FIELD;
1055                 }
1056                 /*
1057                  * Reject READ_* or WRITE_* with overflow/underflow for
1058                  * type SCF_SCSI_DATA_CDB.
1059                  */
1060                 if (dev->dev_attrib.block_size != 512)  {
1061                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1062                                 " CDB on non 512-byte sector setup subsystem"
1063                                 " plugin: %s\n", dev->transport->name);
1064                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1065                         return TCM_INVALID_CDB_FIELD;
1066                 }
1067                 /*
1068                  * For the overflow case keep the existing fabric provided
1069                  * ->data_length.  Otherwise for the underflow case, reset
1070                  * ->data_length to the smaller SCSI expected data transfer
1071                  * length.
1072                  */
1073                 if (size > cmd->data_length) {
1074                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1075                         cmd->residual_count = (size - cmd->data_length);
1076                 } else {
1077                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1078                         cmd->residual_count = (cmd->data_length - size);
1079                         cmd->data_length = size;
1080                 }
1081         }
1082
1083         return 0;
1084
1085 }
1086
1087 /*
1088  * Used by fabric modules containing a local struct se_cmd within their
1089  * fabric dependent per I/O descriptor.
1090  */
1091 void transport_init_se_cmd(
1092         struct se_cmd *cmd,
1093         struct target_core_fabric_ops *tfo,
1094         struct se_session *se_sess,
1095         u32 data_length,
1096         int data_direction,
1097         int task_attr,
1098         unsigned char *sense_buffer)
1099 {
1100         INIT_LIST_HEAD(&cmd->se_delayed_node);
1101         INIT_LIST_HEAD(&cmd->se_qf_node);
1102         INIT_LIST_HEAD(&cmd->se_cmd_list);
1103         INIT_LIST_HEAD(&cmd->state_list);
1104         init_completion(&cmd->t_transport_stop_comp);
1105         init_completion(&cmd->cmd_wait_comp);
1106         init_completion(&cmd->task_stop_comp);
1107         spin_lock_init(&cmd->t_state_lock);
1108         cmd->transport_state = CMD_T_DEV_ACTIVE;
1109
1110         cmd->se_tfo = tfo;
1111         cmd->se_sess = se_sess;
1112         cmd->data_length = data_length;
1113         cmd->data_direction = data_direction;
1114         cmd->sam_task_attr = task_attr;
1115         cmd->sense_buffer = sense_buffer;
1116
1117         cmd->state_active = false;
1118 }
1119 EXPORT_SYMBOL(transport_init_se_cmd);
1120
1121 static sense_reason_t
1122 transport_check_alloc_task_attr(struct se_cmd *cmd)
1123 {
1124         struct se_device *dev = cmd->se_dev;
1125
1126         /*
1127          * Check if SAM Task Attribute emulation is enabled for this
1128          * struct se_device storage object
1129          */
1130         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1131                 return 0;
1132
1133         if (cmd->sam_task_attr == MSG_ACA_TAG) {
1134                 pr_debug("SAM Task Attribute ACA"
1135                         " emulation is not supported\n");
1136                 return TCM_INVALID_CDB_FIELD;
1137         }
1138         /*
1139          * Used to determine when ORDERED commands should go from
1140          * Dormant to Active status.
1141          */
1142         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1143         smp_mb__after_atomic_inc();
1144         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1145                         cmd->se_ordered_id, cmd->sam_task_attr,
1146                         dev->transport->name);
1147         return 0;
1148 }
1149
1150 sense_reason_t
1151 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1152 {
1153         struct se_device *dev = cmd->se_dev;
1154         sense_reason_t ret;
1155
1156         /*
1157          * Ensure that the received CDB is less than the max (252 + 8) bytes
1158          * for VARIABLE_LENGTH_CMD
1159          */
1160         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1161                 pr_err("Received SCSI CDB with command_size: %d that"
1162                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1163                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1164                 return TCM_INVALID_CDB_FIELD;
1165         }
1166         /*
1167          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1168          * allocate the additional extended CDB buffer now..  Otherwise
1169          * setup the pointer from __t_task_cdb to t_task_cdb.
1170          */
1171         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1172                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1173                                                 GFP_KERNEL);
1174                 if (!cmd->t_task_cdb) {
1175                         pr_err("Unable to allocate cmd->t_task_cdb"
1176                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1177                                 scsi_command_size(cdb),
1178                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1179                         return TCM_OUT_OF_RESOURCES;
1180                 }
1181         } else
1182                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1183         /*
1184          * Copy the original CDB into cmd->
1185          */
1186         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1187
1188         trace_target_sequencer_start(cmd);
1189
1190         /*
1191          * Check for an existing UNIT ATTENTION condition
1192          */
1193         ret = target_scsi3_ua_check(cmd);
1194         if (ret)
1195                 return ret;
1196
1197         ret = target_alua_state_check(cmd);
1198         if (ret)
1199                 return ret;
1200
1201         ret = target_check_reservation(cmd);
1202         if (ret) {
1203                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1204                 return ret;
1205         }
1206
1207         ret = dev->transport->parse_cdb(cmd);
1208         if (ret)
1209                 return ret;
1210
1211         ret = transport_check_alloc_task_attr(cmd);
1212         if (ret)
1213                 return ret;
1214
1215         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1216
1217         spin_lock(&cmd->se_lun->lun_sep_lock);
1218         if (cmd->se_lun->lun_sep)
1219                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1220         spin_unlock(&cmd->se_lun->lun_sep_lock);
1221         return 0;
1222 }
1223 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1224
1225 /*
1226  * Used by fabric module frontends to queue tasks directly.
1227  * Many only be used from process context only
1228  */
1229 int transport_handle_cdb_direct(
1230         struct se_cmd *cmd)
1231 {
1232         sense_reason_t ret;
1233
1234         if (!cmd->se_lun) {
1235                 dump_stack();
1236                 pr_err("cmd->se_lun is NULL\n");
1237                 return -EINVAL;
1238         }
1239         if (in_interrupt()) {
1240                 dump_stack();
1241                 pr_err("transport_generic_handle_cdb cannot be called"
1242                                 " from interrupt context\n");
1243                 return -EINVAL;
1244         }
1245         /*
1246          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1247          * outstanding descriptors are handled correctly during shutdown via
1248          * transport_wait_for_tasks()
1249          *
1250          * Also, we don't take cmd->t_state_lock here as we only expect
1251          * this to be called for initial descriptor submission.
1252          */
1253         cmd->t_state = TRANSPORT_NEW_CMD;
1254         cmd->transport_state |= CMD_T_ACTIVE;
1255
1256         /*
1257          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1258          * so follow TRANSPORT_NEW_CMD processing thread context usage
1259          * and call transport_generic_request_failure() if necessary..
1260          */
1261         ret = transport_generic_new_cmd(cmd);
1262         if (ret)
1263                 transport_generic_request_failure(cmd, ret);
1264         return 0;
1265 }
1266 EXPORT_SYMBOL(transport_handle_cdb_direct);
1267
1268 sense_reason_t
1269 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1270                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1271 {
1272         if (!sgl || !sgl_count)
1273                 return 0;
1274
1275         /*
1276          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1277          * scatterlists already have been set to follow what the fabric
1278          * passes for the original expected data transfer length.
1279          */
1280         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1281                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1282                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1283                 return TCM_INVALID_CDB_FIELD;
1284         }
1285
1286         cmd->t_data_sg = sgl;
1287         cmd->t_data_nents = sgl_count;
1288
1289         if (sgl_bidi && sgl_bidi_count) {
1290                 cmd->t_bidi_data_sg = sgl_bidi;
1291                 cmd->t_bidi_data_nents = sgl_bidi_count;
1292         }
1293         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1294         return 0;
1295 }
1296
1297 /*
1298  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1299  *                       se_cmd + use pre-allocated SGL memory.
1300  *
1301  * @se_cmd: command descriptor to submit
1302  * @se_sess: associated se_sess for endpoint
1303  * @cdb: pointer to SCSI CDB
1304  * @sense: pointer to SCSI sense buffer
1305  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1306  * @data_length: fabric expected data transfer length
1307  * @task_addr: SAM task attribute
1308  * @data_dir: DMA data direction
1309  * @flags: flags for command submission from target_sc_flags_tables
1310  * @sgl: struct scatterlist memory for unidirectional mapping
1311  * @sgl_count: scatterlist count for unidirectional mapping
1312  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1313  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1314  * @sgl_prot: struct scatterlist memory protection information
1315  * @sgl_prot_count: scatterlist count for protection information
1316  *
1317  * Returns non zero to signal active I/O shutdown failure.  All other
1318  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1319  * but still return zero here.
1320  *
1321  * This may only be called from process context, and also currently
1322  * assumes internal allocation of fabric payload buffer by target-core.
1323  */
1324 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1325                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1326                 u32 data_length, int task_attr, int data_dir, int flags,
1327                 struct scatterlist *sgl, u32 sgl_count,
1328                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1329                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1330 {
1331         struct se_portal_group *se_tpg;
1332         sense_reason_t rc;
1333         int ret;
1334
1335         se_tpg = se_sess->se_tpg;
1336         BUG_ON(!se_tpg);
1337         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1338         BUG_ON(in_interrupt());
1339         /*
1340          * Initialize se_cmd for target operation.  From this point
1341          * exceptions are handled by sending exception status via
1342          * target_core_fabric_ops->queue_status() callback
1343          */
1344         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1345                                 data_length, data_dir, task_attr, sense);
1346         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1347                 se_cmd->unknown_data_length = 1;
1348         /*
1349          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1350          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1351          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1352          * kref_put() to happen during fabric packet acknowledgement.
1353          */
1354         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1355         if (ret)
1356                 return ret;
1357         /*
1358          * Signal bidirectional data payloads to target-core
1359          */
1360         if (flags & TARGET_SCF_BIDI_OP)
1361                 se_cmd->se_cmd_flags |= SCF_BIDI;
1362         /*
1363          * Locate se_lun pointer and attach it to struct se_cmd
1364          */
1365         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1366         if (rc) {
1367                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1368                 target_put_sess_cmd(se_sess, se_cmd);
1369                 return 0;
1370         }
1371
1372         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1373         if (rc != 0) {
1374                 transport_generic_request_failure(se_cmd, rc);
1375                 return 0;
1376         }
1377
1378         /*
1379          * Save pointers for SGLs containing protection information,
1380          * if present.
1381          */
1382         if (sgl_prot_count) {
1383                 se_cmd->t_prot_sg = sgl_prot;
1384                 se_cmd->t_prot_nents = sgl_prot_count;
1385         }
1386
1387         /*
1388          * When a non zero sgl_count has been passed perform SGL passthrough
1389          * mapping for pre-allocated fabric memory instead of having target
1390          * core perform an internal SGL allocation..
1391          */
1392         if (sgl_count != 0) {
1393                 BUG_ON(!sgl);
1394
1395                 /*
1396                  * A work-around for tcm_loop as some userspace code via
1397                  * scsi-generic do not memset their associated read buffers,
1398                  * so go ahead and do that here for type non-data CDBs.  Also
1399                  * note that this is currently guaranteed to be a single SGL
1400                  * for this case by target core in target_setup_cmd_from_cdb()
1401                  * -> transport_generic_cmd_sequencer().
1402                  */
1403                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1404                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1405                         unsigned char *buf = NULL;
1406
1407                         if (sgl)
1408                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1409
1410                         if (buf) {
1411                                 memset(buf, 0, sgl->length);
1412                                 kunmap(sg_page(sgl));
1413                         }
1414                 }
1415
1416                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1417                                 sgl_bidi, sgl_bidi_count);
1418                 if (rc != 0) {
1419                         transport_generic_request_failure(se_cmd, rc);
1420                         return 0;
1421                 }
1422         }
1423
1424         /*
1425          * Check if we need to delay processing because of ALUA
1426          * Active/NonOptimized primary access state..
1427          */
1428         core_alua_check_nonop_delay(se_cmd);
1429
1430         transport_handle_cdb_direct(se_cmd);
1431         return 0;
1432 }
1433 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1434
1435 /*
1436  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
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  *
1448  * Returns non zero to signal active I/O shutdown failure.  All other
1449  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1450  * but still return zero here.
1451  *
1452  * This may only be called from process context, and also currently
1453  * assumes internal allocation of fabric payload buffer by target-core.
1454  *
1455  * It also assumes interal target core SGL memory allocation.
1456  */
1457 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1458                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1459                 u32 data_length, int task_attr, int data_dir, int flags)
1460 {
1461         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1462                         unpacked_lun, data_length, task_attr, data_dir,
1463                         flags, NULL, 0, NULL, 0, NULL, 0);
1464 }
1465 EXPORT_SYMBOL(target_submit_cmd);
1466
1467 static void target_complete_tmr_failure(struct work_struct *work)
1468 {
1469         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1470
1471         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1472         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1473
1474         transport_cmd_check_stop_to_fabric(se_cmd);
1475 }
1476
1477 /**
1478  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1479  *                     for TMR CDBs
1480  *
1481  * @se_cmd: command descriptor to submit
1482  * @se_sess: associated se_sess for endpoint
1483  * @sense: pointer to SCSI sense buffer
1484  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1485  * @fabric_context: fabric context for TMR req
1486  * @tm_type: Type of TM request
1487  * @gfp: gfp type for caller
1488  * @tag: referenced task tag for TMR_ABORT_TASK
1489  * @flags: submit cmd flags
1490  *
1491  * Callable from all contexts.
1492  **/
1493
1494 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1495                 unsigned char *sense, u32 unpacked_lun,
1496                 void *fabric_tmr_ptr, unsigned char tm_type,
1497                 gfp_t gfp, unsigned int tag, int flags)
1498 {
1499         struct se_portal_group *se_tpg;
1500         int ret;
1501
1502         se_tpg = se_sess->se_tpg;
1503         BUG_ON(!se_tpg);
1504
1505         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1506                               0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1507         /*
1508          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1509          * allocation failure.
1510          */
1511         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1512         if (ret < 0)
1513                 return -ENOMEM;
1514
1515         if (tm_type == TMR_ABORT_TASK)
1516                 se_cmd->se_tmr_req->ref_task_tag = tag;
1517
1518         /* See target_submit_cmd for commentary */
1519         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1520         if (ret) {
1521                 core_tmr_release_req(se_cmd->se_tmr_req);
1522                 return ret;
1523         }
1524
1525         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1526         if (ret) {
1527                 /*
1528                  * For callback during failure handling, push this work off
1529                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1530                  */
1531                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1532                 schedule_work(&se_cmd->work);
1533                 return 0;
1534         }
1535         transport_generic_handle_tmr(se_cmd);
1536         return 0;
1537 }
1538 EXPORT_SYMBOL(target_submit_tmr);
1539
1540 /*
1541  * If the cmd is active, request it to be stopped and sleep until it
1542  * has completed.
1543  */
1544 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1545 {
1546         bool was_active = false;
1547
1548         if (cmd->transport_state & CMD_T_BUSY) {
1549                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1550                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1551
1552                 pr_debug("cmd %p waiting to complete\n", cmd);
1553                 wait_for_completion(&cmd->task_stop_comp);
1554                 pr_debug("cmd %p stopped successfully\n", cmd);
1555
1556                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1557                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1558                 cmd->transport_state &= ~CMD_T_BUSY;
1559                 was_active = true;
1560         }
1561
1562         return was_active;
1563 }
1564
1565 /*
1566  * Handle SAM-esque emulation for generic transport request failures.
1567  */
1568 void transport_generic_request_failure(struct se_cmd *cmd,
1569                 sense_reason_t sense_reason)
1570 {
1571         int ret = 0;
1572
1573         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1574                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1575                 cmd->t_task_cdb[0]);
1576         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1577                 cmd->se_tfo->get_cmd_state(cmd),
1578                 cmd->t_state, sense_reason);
1579         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1580                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1581                 (cmd->transport_state & CMD_T_STOP) != 0,
1582                 (cmd->transport_state & CMD_T_SENT) != 0);
1583
1584         /*
1585          * For SAM Task Attribute emulation for failed struct se_cmd
1586          */
1587         transport_complete_task_attr(cmd);
1588         /*
1589          * Handle special case for COMPARE_AND_WRITE failure, where the
1590          * callback is expected to drop the per device ->caw_mutex.
1591          */
1592         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1593              cmd->transport_complete_callback)
1594                 cmd->transport_complete_callback(cmd);
1595
1596         switch (sense_reason) {
1597         case TCM_NON_EXISTENT_LUN:
1598         case TCM_UNSUPPORTED_SCSI_OPCODE:
1599         case TCM_INVALID_CDB_FIELD:
1600         case TCM_INVALID_PARAMETER_LIST:
1601         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1602         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1603         case TCM_UNKNOWN_MODE_PAGE:
1604         case TCM_WRITE_PROTECTED:
1605         case TCM_ADDRESS_OUT_OF_RANGE:
1606         case TCM_CHECK_CONDITION_ABORT_CMD:
1607         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1608         case TCM_CHECK_CONDITION_NOT_READY:
1609         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1610         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1611         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1612                 break;
1613         case TCM_OUT_OF_RESOURCES:
1614                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1615                 break;
1616         case TCM_RESERVATION_CONFLICT:
1617                 /*
1618                  * No SENSE Data payload for this case, set SCSI Status
1619                  * and queue the response to $FABRIC_MOD.
1620                  *
1621                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1622                  */
1623                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1624                 /*
1625                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1626                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1627                  * CONFLICT STATUS.
1628                  *
1629                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1630                  */
1631                 if (cmd->se_sess &&
1632                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1633                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1634                                 cmd->orig_fe_lun, 0x2C,
1635                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1636
1637                 trace_target_cmd_complete(cmd);
1638                 ret = cmd->se_tfo-> queue_status(cmd);
1639                 if (ret == -EAGAIN || ret == -ENOMEM)
1640                         goto queue_full;
1641                 goto check_stop;
1642         default:
1643                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1644                         cmd->t_task_cdb[0], sense_reason);
1645                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1646                 break;
1647         }
1648
1649         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1650         if (ret == -EAGAIN || ret == -ENOMEM)
1651                 goto queue_full;
1652
1653 check_stop:
1654         transport_lun_remove_cmd(cmd);
1655         if (!transport_cmd_check_stop_to_fabric(cmd))
1656                 ;
1657         return;
1658
1659 queue_full:
1660         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1661         transport_handle_queue_full(cmd, cmd->se_dev);
1662 }
1663 EXPORT_SYMBOL(transport_generic_request_failure);
1664
1665 void __target_execute_cmd(struct se_cmd *cmd)
1666 {
1667         sense_reason_t ret;
1668
1669         if (cmd->execute_cmd) {
1670                 ret = cmd->execute_cmd(cmd);
1671                 if (ret) {
1672                         spin_lock_irq(&cmd->t_state_lock);
1673                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1674                         spin_unlock_irq(&cmd->t_state_lock);
1675
1676                         transport_generic_request_failure(cmd, ret);
1677                 }
1678         }
1679 }
1680
1681 static bool target_handle_task_attr(struct se_cmd *cmd)
1682 {
1683         struct se_device *dev = cmd->se_dev;
1684
1685         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1686                 return false;
1687
1688         /*
1689          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1690          * to allow the passed struct se_cmd list of tasks to the front of the list.
1691          */
1692         switch (cmd->sam_task_attr) {
1693         case MSG_HEAD_TAG:
1694                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1695                          "se_ordered_id: %u\n",
1696                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1697                 return false;
1698         case MSG_ORDERED_TAG:
1699                 atomic_inc(&dev->dev_ordered_sync);
1700                 smp_mb__after_atomic_inc();
1701
1702                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1703                          " se_ordered_id: %u\n",
1704                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1705
1706                 /*
1707                  * Execute an ORDERED command if no other older commands
1708                  * exist that need to be completed first.
1709                  */
1710                 if (!atomic_read(&dev->simple_cmds))
1711                         return false;
1712                 break;
1713         default:
1714                 /*
1715                  * For SIMPLE and UNTAGGED Task Attribute commands
1716                  */
1717                 atomic_inc(&dev->simple_cmds);
1718                 smp_mb__after_atomic_inc();
1719                 break;
1720         }
1721
1722         if (atomic_read(&dev->dev_ordered_sync) == 0)
1723                 return false;
1724
1725         spin_lock(&dev->delayed_cmd_lock);
1726         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1727         spin_unlock(&dev->delayed_cmd_lock);
1728
1729         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1730                 " delayed CMD list, se_ordered_id: %u\n",
1731                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1732                 cmd->se_ordered_id);
1733         return true;
1734 }
1735
1736 void target_execute_cmd(struct se_cmd *cmd)
1737 {
1738         /*
1739          * If the received CDB has aleady been aborted stop processing it here.
1740          */
1741         if (transport_check_aborted_status(cmd, 1))
1742                 return;
1743
1744         /*
1745          * Determine if frontend context caller is requesting the stopping of
1746          * this command for frontend exceptions.
1747          */
1748         spin_lock_irq(&cmd->t_state_lock);
1749         if (cmd->transport_state & CMD_T_STOP) {
1750                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1751                         __func__, __LINE__,
1752                         cmd->se_tfo->get_task_tag(cmd));
1753
1754                 spin_unlock_irq(&cmd->t_state_lock);
1755                 complete(&cmd->t_transport_stop_comp);
1756                 return;
1757         }
1758
1759         cmd->t_state = TRANSPORT_PROCESSING;
1760         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1761         spin_unlock_irq(&cmd->t_state_lock);
1762
1763         if (target_handle_task_attr(cmd)) {
1764                 spin_lock_irq(&cmd->t_state_lock);
1765                 cmd->transport_state &= ~CMD_T_BUSY|CMD_T_SENT;
1766                 spin_unlock_irq(&cmd->t_state_lock);
1767                 return;
1768         }
1769
1770         __target_execute_cmd(cmd);
1771 }
1772 EXPORT_SYMBOL(target_execute_cmd);
1773
1774 /*
1775  * Process all commands up to the last received ORDERED task attribute which
1776  * requires another blocking boundary
1777  */
1778 static void target_restart_delayed_cmds(struct se_device *dev)
1779 {
1780         for (;;) {
1781                 struct se_cmd *cmd;
1782
1783                 spin_lock(&dev->delayed_cmd_lock);
1784                 if (list_empty(&dev->delayed_cmd_list)) {
1785                         spin_unlock(&dev->delayed_cmd_lock);
1786                         break;
1787                 }
1788
1789                 cmd = list_entry(dev->delayed_cmd_list.next,
1790                                  struct se_cmd, se_delayed_node);
1791                 list_del(&cmd->se_delayed_node);
1792                 spin_unlock(&dev->delayed_cmd_lock);
1793
1794                 __target_execute_cmd(cmd);
1795
1796                 if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1797                         break;
1798         }
1799 }
1800
1801 /*
1802  * Called from I/O completion to determine which dormant/delayed
1803  * and ordered cmds need to have their tasks added to the execution queue.
1804  */
1805 static void transport_complete_task_attr(struct se_cmd *cmd)
1806 {
1807         struct se_device *dev = cmd->se_dev;
1808
1809         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1810                 return;
1811
1812         if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1813                 atomic_dec(&dev->simple_cmds);
1814                 smp_mb__after_atomic_dec();
1815                 dev->dev_cur_ordered_id++;
1816                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1817                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1818                         cmd->se_ordered_id);
1819         } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1820                 dev->dev_cur_ordered_id++;
1821                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1822                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1823                         cmd->se_ordered_id);
1824         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1825                 atomic_dec(&dev->dev_ordered_sync);
1826                 smp_mb__after_atomic_dec();
1827
1828                 dev->dev_cur_ordered_id++;
1829                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1830                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1831         }
1832
1833         target_restart_delayed_cmds(dev);
1834 }
1835
1836 static void transport_complete_qf(struct se_cmd *cmd)
1837 {
1838         int ret = 0;
1839
1840         transport_complete_task_attr(cmd);
1841
1842         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1843                 trace_target_cmd_complete(cmd);
1844                 ret = cmd->se_tfo->queue_status(cmd);
1845                 if (ret)
1846                         goto out;
1847         }
1848
1849         switch (cmd->data_direction) {
1850         case DMA_FROM_DEVICE:
1851                 trace_target_cmd_complete(cmd);
1852                 ret = cmd->se_tfo->queue_data_in(cmd);
1853                 break;
1854         case DMA_TO_DEVICE:
1855                 if (cmd->se_cmd_flags & SCF_BIDI) {
1856                         ret = cmd->se_tfo->queue_data_in(cmd);
1857                         if (ret < 0)
1858                                 break;
1859                 }
1860                 /* Fall through for DMA_TO_DEVICE */
1861         case DMA_NONE:
1862                 trace_target_cmd_complete(cmd);
1863                 ret = cmd->se_tfo->queue_status(cmd);
1864                 break;
1865         default:
1866                 break;
1867         }
1868
1869 out:
1870         if (ret < 0) {
1871                 transport_handle_queue_full(cmd, cmd->se_dev);
1872                 return;
1873         }
1874         transport_lun_remove_cmd(cmd);
1875         transport_cmd_check_stop_to_fabric(cmd);
1876 }
1877
1878 static void transport_handle_queue_full(
1879         struct se_cmd *cmd,
1880         struct se_device *dev)
1881 {
1882         spin_lock_irq(&dev->qf_cmd_lock);
1883         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1884         atomic_inc(&dev->dev_qf_count);
1885         smp_mb__after_atomic_inc();
1886         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1887
1888         schedule_work(&cmd->se_dev->qf_work_queue);
1889 }
1890
1891 static void target_complete_ok_work(struct work_struct *work)
1892 {
1893         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1894         int ret;
1895
1896         /*
1897          * Check if we need to move delayed/dormant tasks from cmds on the
1898          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1899          * Attribute.
1900          */
1901         transport_complete_task_attr(cmd);
1902
1903         /*
1904          * Check to schedule QUEUE_FULL work, or execute an existing
1905          * cmd->transport_qf_callback()
1906          */
1907         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1908                 schedule_work(&cmd->se_dev->qf_work_queue);
1909
1910         /*
1911          * Check if we need to send a sense buffer from
1912          * the struct se_cmd in question.
1913          */
1914         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1915                 WARN_ON(!cmd->scsi_status);
1916                 ret = transport_send_check_condition_and_sense(
1917                                         cmd, 0, 1);
1918                 if (ret == -EAGAIN || ret == -ENOMEM)
1919                         goto queue_full;
1920
1921                 transport_lun_remove_cmd(cmd);
1922                 transport_cmd_check_stop_to_fabric(cmd);
1923                 return;
1924         }
1925         /*
1926          * Check for a callback, used by amongst other things
1927          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
1928          */
1929         if (cmd->transport_complete_callback) {
1930                 sense_reason_t rc;
1931
1932                 rc = cmd->transport_complete_callback(cmd);
1933                 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
1934                         return;
1935                 } else if (rc) {
1936                         ret = transport_send_check_condition_and_sense(cmd,
1937                                                 rc, 0);
1938                         if (ret == -EAGAIN || ret == -ENOMEM)
1939                                 goto queue_full;
1940
1941                         transport_lun_remove_cmd(cmd);
1942                         transport_cmd_check_stop_to_fabric(cmd);
1943                         return;
1944                 }
1945         }
1946
1947         switch (cmd->data_direction) {
1948         case DMA_FROM_DEVICE:
1949                 spin_lock(&cmd->se_lun->lun_sep_lock);
1950                 if (cmd->se_lun->lun_sep) {
1951                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1952                                         cmd->data_length;
1953                 }
1954                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1955
1956                 trace_target_cmd_complete(cmd);
1957                 ret = cmd->se_tfo->queue_data_in(cmd);
1958                 if (ret == -EAGAIN || ret == -ENOMEM)
1959                         goto queue_full;
1960                 break;
1961         case DMA_TO_DEVICE:
1962                 spin_lock(&cmd->se_lun->lun_sep_lock);
1963                 if (cmd->se_lun->lun_sep) {
1964                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
1965                                 cmd->data_length;
1966                 }
1967                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1968                 /*
1969                  * Check if we need to send READ payload for BIDI-COMMAND
1970                  */
1971                 if (cmd->se_cmd_flags & SCF_BIDI) {
1972                         spin_lock(&cmd->se_lun->lun_sep_lock);
1973                         if (cmd->se_lun->lun_sep) {
1974                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1975                                         cmd->data_length;
1976                         }
1977                         spin_unlock(&cmd->se_lun->lun_sep_lock);
1978                         ret = cmd->se_tfo->queue_data_in(cmd);
1979                         if (ret == -EAGAIN || ret == -ENOMEM)
1980                                 goto queue_full;
1981                         break;
1982                 }
1983                 /* Fall through for DMA_TO_DEVICE */
1984         case DMA_NONE:
1985                 trace_target_cmd_complete(cmd);
1986                 ret = cmd->se_tfo->queue_status(cmd);
1987                 if (ret == -EAGAIN || ret == -ENOMEM)
1988                         goto queue_full;
1989                 break;
1990         default:
1991                 break;
1992         }
1993
1994         transport_lun_remove_cmd(cmd);
1995         transport_cmd_check_stop_to_fabric(cmd);
1996         return;
1997
1998 queue_full:
1999         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2000                 " data_direction: %d\n", cmd, cmd->data_direction);
2001         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2002         transport_handle_queue_full(cmd, cmd->se_dev);
2003 }
2004
2005 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2006 {
2007         struct scatterlist *sg;
2008         int count;
2009
2010         for_each_sg(sgl, sg, nents, count)
2011                 __free_page(sg_page(sg));
2012
2013         kfree(sgl);
2014 }
2015
2016 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2017 {
2018         /*
2019          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2020          * emulation, and free + reset pointers if necessary..
2021          */
2022         if (!cmd->t_data_sg_orig)
2023                 return;
2024
2025         kfree(cmd->t_data_sg);
2026         cmd->t_data_sg = cmd->t_data_sg_orig;
2027         cmd->t_data_sg_orig = NULL;
2028         cmd->t_data_nents = cmd->t_data_nents_orig;
2029         cmd->t_data_nents_orig = 0;
2030 }
2031
2032 static inline void transport_free_pages(struct se_cmd *cmd)
2033 {
2034         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2035                 transport_reset_sgl_orig(cmd);
2036                 return;
2037         }
2038         transport_reset_sgl_orig(cmd);
2039
2040         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2041         cmd->t_data_sg = NULL;
2042         cmd->t_data_nents = 0;
2043
2044         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2045         cmd->t_bidi_data_sg = NULL;
2046         cmd->t_bidi_data_nents = 0;
2047
2048         transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2049         cmd->t_prot_sg = NULL;
2050         cmd->t_prot_nents = 0;
2051 }
2052
2053 /**
2054  * transport_release_cmd - free a command
2055  * @cmd:       command to free
2056  *
2057  * This routine unconditionally frees a command, and reference counting
2058  * or list removal must be done in the caller.
2059  */
2060 static int transport_release_cmd(struct se_cmd *cmd)
2061 {
2062         BUG_ON(!cmd->se_tfo);
2063
2064         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2065                 core_tmr_release_req(cmd->se_tmr_req);
2066         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2067                 kfree(cmd->t_task_cdb);
2068         /*
2069          * If this cmd has been setup with target_get_sess_cmd(), drop
2070          * the kref and call ->release_cmd() in kref callback.
2071          */
2072         return target_put_sess_cmd(cmd->se_sess, cmd);
2073 }
2074
2075 /**
2076  * transport_put_cmd - release a reference to a command
2077  * @cmd:       command to release
2078  *
2079  * This routine releases our reference to the command and frees it if possible.
2080  */
2081 static int transport_put_cmd(struct se_cmd *cmd)
2082 {
2083         transport_free_pages(cmd);
2084         return transport_release_cmd(cmd);
2085 }
2086
2087 void *transport_kmap_data_sg(struct se_cmd *cmd)
2088 {
2089         struct scatterlist *sg = cmd->t_data_sg;
2090         struct page **pages;
2091         int i;
2092
2093         /*
2094          * We need to take into account a possible offset here for fabrics like
2095          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2096          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2097          */
2098         if (!cmd->t_data_nents)
2099                 return NULL;
2100
2101         BUG_ON(!sg);
2102         if (cmd->t_data_nents == 1)
2103                 return kmap(sg_page(sg)) + sg->offset;
2104
2105         /* >1 page. use vmap */
2106         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2107         if (!pages)
2108                 return NULL;
2109
2110         /* convert sg[] to pages[] */
2111         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2112                 pages[i] = sg_page(sg);
2113         }
2114
2115         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2116         kfree(pages);
2117         if (!cmd->t_data_vmap)
2118                 return NULL;
2119
2120         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2121 }
2122 EXPORT_SYMBOL(transport_kmap_data_sg);
2123
2124 void transport_kunmap_data_sg(struct se_cmd *cmd)
2125 {
2126         if (!cmd->t_data_nents) {
2127                 return;
2128         } else if (cmd->t_data_nents == 1) {
2129                 kunmap(sg_page(cmd->t_data_sg));
2130                 return;
2131         }
2132
2133         vunmap(cmd->t_data_vmap);
2134         cmd->t_data_vmap = NULL;
2135 }
2136 EXPORT_SYMBOL(transport_kunmap_data_sg);
2137
2138 int
2139 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2140                  bool zero_page)
2141 {
2142         struct scatterlist *sg;
2143         struct page *page;
2144         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2145         unsigned int nent;
2146         int i = 0;
2147
2148         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2149         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2150         if (!sg)
2151                 return -ENOMEM;
2152
2153         sg_init_table(sg, nent);
2154
2155         while (length) {
2156                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2157                 page = alloc_page(GFP_KERNEL | zero_flag);
2158                 if (!page)
2159                         goto out;
2160
2161                 sg_set_page(&sg[i], page, page_len, 0);
2162                 length -= page_len;
2163                 i++;
2164         }
2165         *sgl = sg;
2166         *nents = nent;
2167         return 0;
2168
2169 out:
2170         while (i > 0) {
2171                 i--;
2172                 __free_page(sg_page(&sg[i]));
2173         }
2174         kfree(sg);
2175         return -ENOMEM;
2176 }
2177
2178 /*
2179  * Allocate any required resources to execute the command.  For writes we
2180  * might not have the payload yet, so notify the fabric via a call to
2181  * ->write_pending instead. Otherwise place it on the execution queue.
2182  */
2183 sense_reason_t
2184 transport_generic_new_cmd(struct se_cmd *cmd)
2185 {
2186         int ret = 0;
2187
2188         /*
2189          * Determine is the TCM fabric module has already allocated physical
2190          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2191          * beforehand.
2192          */
2193         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2194             cmd->data_length) {
2195                 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2196
2197                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2198                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2199                         u32 bidi_length;
2200
2201                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2202                                 bidi_length = cmd->t_task_nolb *
2203                                               cmd->se_dev->dev_attrib.block_size;
2204                         else
2205                                 bidi_length = cmd->data_length;
2206
2207                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2208                                                &cmd->t_bidi_data_nents,
2209                                                bidi_length, zero_flag);
2210                         if (ret < 0)
2211                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2212                 }
2213
2214                 if (cmd->prot_op != TARGET_PROT_NORMAL) {
2215                         ret = target_alloc_sgl(&cmd->t_prot_sg,
2216                                                &cmd->t_prot_nents,
2217                                                cmd->prot_length, true);
2218                         if (ret < 0)
2219                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2220                 }
2221
2222                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2223                                        cmd->data_length, zero_flag);
2224                 if (ret < 0)
2225                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2226         }
2227         /*
2228          * If this command is not a write we can execute it right here,
2229          * for write buffers we need to notify the fabric driver first
2230          * and let it call back once the write buffers are ready.
2231          */
2232         target_add_to_state_list(cmd);
2233         if (cmd->data_direction != DMA_TO_DEVICE) {
2234                 target_execute_cmd(cmd);
2235                 return 0;
2236         }
2237         transport_cmd_check_stop(cmd, false, true);
2238
2239         ret = cmd->se_tfo->write_pending(cmd);
2240         if (ret == -EAGAIN || ret == -ENOMEM)
2241                 goto queue_full;
2242
2243         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2244         WARN_ON(ret);
2245
2246         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2247
2248 queue_full:
2249         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2250         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2251         transport_handle_queue_full(cmd, cmd->se_dev);
2252         return 0;
2253 }
2254 EXPORT_SYMBOL(transport_generic_new_cmd);
2255
2256 static void transport_write_pending_qf(struct se_cmd *cmd)
2257 {
2258         int ret;
2259
2260         ret = cmd->se_tfo->write_pending(cmd);
2261         if (ret == -EAGAIN || ret == -ENOMEM) {
2262                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2263                          cmd);
2264                 transport_handle_queue_full(cmd, cmd->se_dev);
2265         }
2266 }
2267
2268 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2269 {
2270         unsigned long flags;
2271         int ret = 0;
2272
2273         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2274                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2275                          transport_wait_for_tasks(cmd);
2276
2277                 ret = transport_release_cmd(cmd);
2278         } else {
2279                 if (wait_for_tasks)
2280                         transport_wait_for_tasks(cmd);
2281                 /*
2282                  * Handle WRITE failure case where transport_generic_new_cmd()
2283                  * has already added se_cmd to state_list, but fabric has
2284                  * failed command before I/O submission.
2285                  */
2286                 if (cmd->state_active) {
2287                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2288                         target_remove_from_state_list(cmd);
2289                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2290                 }
2291
2292                 if (cmd->se_lun)
2293                         transport_lun_remove_cmd(cmd);
2294
2295                 ret = transport_put_cmd(cmd);
2296         }
2297         return ret;
2298 }
2299 EXPORT_SYMBOL(transport_generic_free_cmd);
2300
2301 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2302  * @se_sess:    session to reference
2303  * @se_cmd:     command descriptor to add
2304  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2305  */
2306 int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2307                                bool ack_kref)
2308 {
2309         unsigned long flags;
2310         int ret = 0;
2311
2312         kref_init(&se_cmd->cmd_kref);
2313         /*
2314          * Add a second kref if the fabric caller is expecting to handle
2315          * fabric acknowledgement that requires two target_put_sess_cmd()
2316          * invocations before se_cmd descriptor release.
2317          */
2318         if (ack_kref == true) {
2319                 kref_get(&se_cmd->cmd_kref);
2320                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2321         }
2322
2323         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2324         if (se_sess->sess_tearing_down) {
2325                 ret = -ESHUTDOWN;
2326                 goto out;
2327         }
2328         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2329 out:
2330         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2331         return ret;
2332 }
2333 EXPORT_SYMBOL(target_get_sess_cmd);
2334
2335 static void target_release_cmd_kref(struct kref *kref)
2336 {
2337         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2338         struct se_session *se_sess = se_cmd->se_sess;
2339
2340         if (list_empty(&se_cmd->se_cmd_list)) {
2341                 spin_unlock(&se_sess->sess_cmd_lock);
2342                 se_cmd->se_tfo->release_cmd(se_cmd);
2343                 return;
2344         }
2345         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2346                 spin_unlock(&se_sess->sess_cmd_lock);
2347                 complete(&se_cmd->cmd_wait_comp);
2348                 return;
2349         }
2350         list_del(&se_cmd->se_cmd_list);
2351         spin_unlock(&se_sess->sess_cmd_lock);
2352
2353         se_cmd->se_tfo->release_cmd(se_cmd);
2354 }
2355
2356 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2357  * @se_sess:    session to reference
2358  * @se_cmd:     command descriptor to drop
2359  */
2360 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2361 {
2362         return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2363                         &se_sess->sess_cmd_lock);
2364 }
2365 EXPORT_SYMBOL(target_put_sess_cmd);
2366
2367 /* target_sess_cmd_list_set_waiting - Flag all commands in
2368  *         sess_cmd_list to complete cmd_wait_comp.  Set
2369  *         sess_tearing_down so no more commands are queued.
2370  * @se_sess:    session to flag
2371  */
2372 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2373 {
2374         struct se_cmd *se_cmd;
2375         unsigned long flags;
2376
2377         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2378         if (se_sess->sess_tearing_down) {
2379                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2380                 return;
2381         }
2382         se_sess->sess_tearing_down = 1;
2383         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2384
2385         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2386                 se_cmd->cmd_wait_set = 1;
2387
2388         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2389 }
2390 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2391
2392 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2393  * @se_sess:    session to wait for active I/O
2394  */
2395 void target_wait_for_sess_cmds(struct se_session *se_sess)
2396 {
2397         struct se_cmd *se_cmd, *tmp_cmd;
2398         unsigned long flags;
2399
2400         list_for_each_entry_safe(se_cmd, tmp_cmd,
2401                                 &se_sess->sess_wait_list, se_cmd_list) {
2402                 list_del(&se_cmd->se_cmd_list);
2403
2404                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2405                         " %d\n", se_cmd, se_cmd->t_state,
2406                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2407
2408                 wait_for_completion(&se_cmd->cmd_wait_comp);
2409                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2410                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2411                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2412
2413                 se_cmd->se_tfo->release_cmd(se_cmd);
2414         }
2415
2416         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2417         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2418         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2419
2420 }
2421 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2422
2423 static int transport_clear_lun_ref_thread(void *p)
2424 {
2425         struct se_lun *lun = p;
2426
2427         percpu_ref_kill(&lun->lun_ref);
2428
2429         wait_for_completion(&lun->lun_ref_comp);
2430         complete(&lun->lun_shutdown_comp);
2431
2432         return 0;
2433 }
2434
2435 int transport_clear_lun_ref(struct se_lun *lun)
2436 {
2437         struct task_struct *kt;
2438
2439         kt = kthread_run(transport_clear_lun_ref_thread, lun,
2440                         "tcm_cl_%u", lun->unpacked_lun);
2441         if (IS_ERR(kt)) {
2442                 pr_err("Unable to start clear_lun thread\n");
2443                 return PTR_ERR(kt);
2444         }
2445         wait_for_completion(&lun->lun_shutdown_comp);
2446
2447         return 0;
2448 }
2449
2450 /**
2451  * transport_wait_for_tasks - wait for completion to occur
2452  * @cmd:        command to wait
2453  *
2454  * Called from frontend fabric context to wait for storage engine
2455  * to pause and/or release frontend generated struct se_cmd.
2456  */
2457 bool transport_wait_for_tasks(struct se_cmd *cmd)
2458 {
2459         unsigned long flags;
2460
2461         spin_lock_irqsave(&cmd->t_state_lock, flags);
2462         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2463             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2464                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2465                 return false;
2466         }
2467
2468         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2469             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2470                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2471                 return false;
2472         }
2473
2474         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2475                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2476                 return false;
2477         }
2478
2479         cmd->transport_state |= CMD_T_STOP;
2480
2481         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2482                 " i_state: %d, t_state: %d, CMD_T_STOP\n",
2483                 cmd, cmd->se_tfo->get_task_tag(cmd),
2484                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2485
2486         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2487
2488         wait_for_completion(&cmd->t_transport_stop_comp);
2489
2490         spin_lock_irqsave(&cmd->t_state_lock, flags);
2491         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2492
2493         pr_debug("wait_for_tasks: Stopped wait_for_completion("
2494                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2495                 cmd->se_tfo->get_task_tag(cmd));
2496
2497         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2498
2499         return true;
2500 }
2501 EXPORT_SYMBOL(transport_wait_for_tasks);
2502
2503 static int transport_get_sense_codes(
2504         struct se_cmd *cmd,
2505         u8 *asc,
2506         u8 *ascq)
2507 {
2508         *asc = cmd->scsi_asc;
2509         *ascq = cmd->scsi_ascq;
2510
2511         return 0;
2512 }
2513
2514 static
2515 void transport_err_sector_info(unsigned char *buffer, sector_t bad_sector)
2516 {
2517         /* Place failed LBA in sense data information descriptor 0. */
2518         buffer[SPC_ADD_SENSE_LEN_OFFSET] = 0xc;
2519         buffer[SPC_DESC_TYPE_OFFSET] = 0; /* Information */
2520         buffer[SPC_ADDITIONAL_DESC_LEN_OFFSET] = 0xa;
2521         buffer[SPC_VALIDITY_OFFSET] = 0x80;
2522
2523         /* Descriptor Information: failing sector */
2524         put_unaligned_be64(bad_sector, &buffer[12]);
2525 }
2526
2527 int
2528 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2529                 sense_reason_t reason, int from_transport)
2530 {
2531         unsigned char *buffer = cmd->sense_buffer;
2532         unsigned long flags;
2533         u8 asc = 0, ascq = 0;
2534
2535         spin_lock_irqsave(&cmd->t_state_lock, flags);
2536         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2537                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2538                 return 0;
2539         }
2540         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2541         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2542
2543         if (!reason && from_transport)
2544                 goto after_reason;
2545
2546         if (!from_transport)
2547                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2548
2549         /*
2550          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2551          * SENSE KEY values from include/scsi/scsi.h
2552          */
2553         switch (reason) {
2554         case TCM_NO_SENSE:
2555                 /* CURRENT ERROR */
2556                 buffer[0] = 0x70;
2557                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2558                 /* Not Ready */
2559                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2560                 /* NO ADDITIONAL SENSE INFORMATION */
2561                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2562                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2563                 break;
2564         case TCM_NON_EXISTENT_LUN:
2565                 /* CURRENT ERROR */
2566                 buffer[0] = 0x70;
2567                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2568                 /* ILLEGAL REQUEST */
2569                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2570                 /* LOGICAL UNIT NOT SUPPORTED */
2571                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2572                 break;
2573         case TCM_UNSUPPORTED_SCSI_OPCODE:
2574         case TCM_SECTOR_COUNT_TOO_MANY:
2575                 /* CURRENT ERROR */
2576                 buffer[0] = 0x70;
2577                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2578                 /* ILLEGAL REQUEST */
2579                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2580                 /* INVALID COMMAND OPERATION CODE */
2581                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2582                 break;
2583         case TCM_UNKNOWN_MODE_PAGE:
2584                 /* CURRENT ERROR */
2585                 buffer[0] = 0x70;
2586                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2587                 /* ILLEGAL REQUEST */
2588                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2589                 /* INVALID FIELD IN CDB */
2590                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2591                 break;
2592         case TCM_CHECK_CONDITION_ABORT_CMD:
2593                 /* CURRENT ERROR */
2594                 buffer[0] = 0x70;
2595                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2596                 /* ABORTED COMMAND */
2597                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2598                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2599                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2600                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2601                 break;
2602         case TCM_INCORRECT_AMOUNT_OF_DATA:
2603                 /* CURRENT ERROR */
2604                 buffer[0] = 0x70;
2605                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2606                 /* ABORTED COMMAND */
2607                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2608                 /* WRITE ERROR */
2609                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2610                 /* NOT ENOUGH UNSOLICITED DATA */
2611                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2612                 break;
2613         case TCM_INVALID_CDB_FIELD:
2614                 /* CURRENT ERROR */
2615                 buffer[0] = 0x70;
2616                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2617                 /* ILLEGAL REQUEST */
2618                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2619                 /* INVALID FIELD IN CDB */
2620                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2621                 break;
2622         case TCM_INVALID_PARAMETER_LIST:
2623                 /* CURRENT ERROR */
2624                 buffer[0] = 0x70;
2625                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2626                 /* ILLEGAL REQUEST */
2627                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2628                 /* INVALID FIELD IN PARAMETER LIST */
2629                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2630                 break;
2631         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2632                 /* CURRENT ERROR */
2633                 buffer[0] = 0x70;
2634                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2635                 /* ILLEGAL REQUEST */
2636                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2637                 /* PARAMETER LIST LENGTH ERROR */
2638                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2639                 break;
2640         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2641                 /* CURRENT ERROR */
2642                 buffer[0] = 0x70;
2643                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2644                 /* ABORTED COMMAND */
2645                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2646                 /* WRITE ERROR */
2647                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2648                 /* UNEXPECTED_UNSOLICITED_DATA */
2649                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2650                 break;
2651         case TCM_SERVICE_CRC_ERROR:
2652                 /* CURRENT ERROR */
2653                 buffer[0] = 0x70;
2654                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2655                 /* ABORTED COMMAND */
2656                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2657                 /* PROTOCOL SERVICE CRC ERROR */
2658                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2659                 /* N/A */
2660                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2661                 break;
2662         case TCM_SNACK_REJECTED:
2663                 /* CURRENT ERROR */
2664                 buffer[0] = 0x70;
2665                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2666                 /* ABORTED COMMAND */
2667                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2668                 /* READ ERROR */
2669                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2670                 /* FAILED RETRANSMISSION REQUEST */
2671                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2672                 break;
2673         case TCM_WRITE_PROTECTED:
2674                 /* CURRENT ERROR */
2675                 buffer[0] = 0x70;
2676                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2677                 /* DATA PROTECT */
2678                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2679                 /* WRITE PROTECTED */
2680                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2681                 break;
2682         case TCM_ADDRESS_OUT_OF_RANGE:
2683                 /* CURRENT ERROR */
2684                 buffer[0] = 0x70;
2685                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2686                 /* ILLEGAL REQUEST */
2687                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2688                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2689                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2690                 break;
2691         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2692                 /* CURRENT ERROR */
2693                 buffer[0] = 0x70;
2694                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2695                 /* UNIT ATTENTION */
2696                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2697                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2698                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2699                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2700                 break;
2701         case TCM_CHECK_CONDITION_NOT_READY:
2702                 /* CURRENT ERROR */
2703                 buffer[0] = 0x70;
2704                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2705                 /* Not Ready */
2706                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2707                 transport_get_sense_codes(cmd, &asc, &ascq);
2708                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2709                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2710                 break;
2711         case TCM_MISCOMPARE_VERIFY:
2712                 /* CURRENT ERROR */
2713                 buffer[0] = 0x70;
2714                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2715                 buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
2716                 /* MISCOMPARE DURING VERIFY OPERATION */
2717                 buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
2718                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
2719                 break;
2720         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
2721                 /* CURRENT ERROR */
2722                 buffer[0] = 0x70;
2723                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2724                 /* ILLEGAL REQUEST */
2725                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2726                 /* LOGICAL BLOCK GUARD CHECK FAILED */
2727                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2728                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x01;
2729                 transport_err_sector_info(buffer, cmd->bad_sector);
2730                 break;
2731         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
2732                 /* CURRENT ERROR */
2733                 buffer[0] = 0x70;
2734                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2735                 /* ILLEGAL REQUEST */
2736                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2737                 /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2738                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2739                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x02;
2740                 transport_err_sector_info(buffer, cmd->bad_sector);
2741                 break;
2742         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
2743                 /* CURRENT ERROR */
2744                 buffer[0] = 0x70;
2745                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2746                 /* ILLEGAL REQUEST */
2747                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2748                 /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2749                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2750                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2751                 transport_err_sector_info(buffer, cmd->bad_sector);
2752                 break;
2753         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2754         default:
2755                 /* CURRENT ERROR */
2756                 buffer[0] = 0x70;
2757                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2758                 /*
2759                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2760                  * Solaris initiators.  Returning NOT READY instead means the
2761                  * operations will be retried a finite number of times and we
2762                  * can survive intermittent errors.
2763                  */
2764                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2765                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2766                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2767                 break;
2768         }
2769         /*
2770          * This code uses linux/include/scsi/scsi.h SAM status codes!
2771          */
2772         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2773         /*
2774          * Automatically padded, this value is encoded in the fabric's
2775          * data_length response PDU containing the SCSI defined sense data.
2776          */
2777         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2778
2779 after_reason:
2780         trace_target_cmd_complete(cmd);
2781         return cmd->se_tfo->queue_status(cmd);
2782 }
2783 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2784
2785 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2786 {
2787         if (!(cmd->transport_state & CMD_T_ABORTED))
2788                 return 0;
2789
2790         /*
2791          * If cmd has been aborted but either no status is to be sent or it has
2792          * already been sent, just return
2793          */
2794         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
2795                 return 1;
2796
2797         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2798                  cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2799
2800         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2801         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2802         trace_target_cmd_complete(cmd);
2803         cmd->se_tfo->queue_status(cmd);
2804
2805         return 1;
2806 }
2807 EXPORT_SYMBOL(transport_check_aborted_status);
2808
2809 void transport_send_task_abort(struct se_cmd *cmd)
2810 {
2811         unsigned long flags;
2812
2813         spin_lock_irqsave(&cmd->t_state_lock, flags);
2814         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2815                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2816                 return;
2817         }
2818         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2819
2820         /*
2821          * If there are still expected incoming fabric WRITEs, we wait
2822          * until until they have completed before sending a TASK_ABORTED
2823          * response.  This response with TASK_ABORTED status will be
2824          * queued back to fabric module by transport_check_aborted_status().
2825          */
2826         if (cmd->data_direction == DMA_TO_DEVICE) {
2827                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2828                         cmd->transport_state |= CMD_T_ABORTED;
2829                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2830                         smp_mb__after_atomic_inc();
2831                         return;
2832                 }
2833         }
2834         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2835
2836         transport_lun_remove_cmd(cmd);
2837
2838         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2839                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
2840                 cmd->se_tfo->get_task_tag(cmd));
2841
2842         trace_target_cmd_complete(cmd);
2843         cmd->se_tfo->queue_status(cmd);
2844 }
2845
2846 static void target_tmr_work(struct work_struct *work)
2847 {
2848         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2849         struct se_device *dev = cmd->se_dev;
2850         struct se_tmr_req *tmr = cmd->se_tmr_req;
2851         int ret;
2852
2853         switch (tmr->function) {
2854         case TMR_ABORT_TASK:
2855                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2856                 break;
2857         case TMR_ABORT_TASK_SET:
2858         case TMR_CLEAR_ACA:
2859         case TMR_CLEAR_TASK_SET:
2860                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2861                 break;
2862         case TMR_LUN_RESET:
2863                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2864                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2865                                          TMR_FUNCTION_REJECTED;
2866                 break;
2867         case TMR_TARGET_WARM_RESET:
2868                 tmr->response = TMR_FUNCTION_REJECTED;
2869                 break;
2870         case TMR_TARGET_COLD_RESET:
2871                 tmr->response = TMR_FUNCTION_REJECTED;
2872                 break;
2873         default:
2874                 pr_err("Uknown TMR function: 0x%02x.\n",
2875                                 tmr->function);
2876                 tmr->response = TMR_FUNCTION_REJECTED;
2877                 break;
2878         }
2879
2880         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2881         cmd->se_tfo->queue_tm_rsp(cmd);
2882
2883         transport_cmd_check_stop_to_fabric(cmd);
2884 }
2885
2886 int transport_generic_handle_tmr(
2887         struct se_cmd *cmd)
2888 {
2889         INIT_WORK(&cmd->work, target_tmr_work);
2890         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2891         return 0;
2892 }
2893 EXPORT_SYMBOL(transport_generic_handle_tmr);