target: remove the t_tasks_fua se_cmd field
[linux-2.6.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  * Copyright (c) 2002, 2003, 2004, 2005 PyX Technologies, Inc.
7  * Copyright (c) 2005, 2006, 2007 SBE, Inc.
8  * Copyright (c) 2007-2010 Rising Tide Systems
9  * Copyright (c) 2008-2010 Linux-iSCSI.org
10  *
11  * Nicholas A. Bellinger <nab@kernel.org>
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26  *
27  ******************************************************************************/
28
29 #include <linux/net.h>
30 #include <linux/delay.h>
31 #include <linux/string.h>
32 #include <linux/timer.h>
33 #include <linux/slab.h>
34 #include <linux/blkdev.h>
35 #include <linux/spinlock.h>
36 #include <linux/kthread.h>
37 #include <linux/in.h>
38 #include <linux/cdrom.h>
39 #include <linux/module.h>
40 #include <asm/unaligned.h>
41 #include <net/sock.h>
42 #include <net/tcp.h>
43 #include <scsi/scsi.h>
44 #include <scsi/scsi_cmnd.h>
45 #include <scsi/scsi_tcq.h>
46
47 #include <target/target_core_base.h>
48 #include <target/target_core_device.h>
49 #include <target/target_core_tmr.h>
50 #include <target/target_core_tpg.h>
51 #include <target/target_core_transport.h>
52 #include <target/target_core_fabric_ops.h>
53 #include <target/target_core_configfs.h>
54
55 #include "target_core_alua.h"
56 #include "target_core_cdb.h"
57 #include "target_core_hba.h"
58 #include "target_core_pr.h"
59 #include "target_core_ua.h"
60
61 static int sub_api_initialized;
62
63 static struct workqueue_struct *target_completion_wq;
64 static struct kmem_cache *se_sess_cache;
65 struct kmem_cache *se_tmr_req_cache;
66 struct kmem_cache *se_ua_cache;
67 struct kmem_cache *t10_pr_reg_cache;
68 struct kmem_cache *t10_alua_lu_gp_cache;
69 struct kmem_cache *t10_alua_lu_gp_mem_cache;
70 struct kmem_cache *t10_alua_tg_pt_gp_cache;
71 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
72
73 static int transport_generic_write_pending(struct se_cmd *);
74 static int transport_processing_thread(void *param);
75 static int __transport_execute_tasks(struct se_device *dev);
76 static void transport_complete_task_attr(struct se_cmd *cmd);
77 static void transport_handle_queue_full(struct se_cmd *cmd,
78                 struct se_device *dev);
79 static void transport_free_dev_tasks(struct se_cmd *cmd);
80 static int transport_generic_get_mem(struct se_cmd *cmd);
81 static void transport_put_cmd(struct se_cmd *cmd);
82 static void transport_remove_cmd_from_queue(struct se_cmd *cmd);
83 static int transport_set_sense_codes(struct se_cmd *cmd, u8 asc, u8 ascq);
84 static void transport_generic_request_failure(struct se_cmd *);
85 static void target_complete_ok_work(struct work_struct *work);
86
87 int init_se_kmem_caches(void)
88 {
89         se_tmr_req_cache = kmem_cache_create("se_tmr_cache",
90                         sizeof(struct se_tmr_req), __alignof__(struct se_tmr_req),
91                         0, NULL);
92         if (!se_tmr_req_cache) {
93                 pr_err("kmem_cache_create() for struct se_tmr_req"
94                                 " failed\n");
95                 goto out;
96         }
97         se_sess_cache = kmem_cache_create("se_sess_cache",
98                         sizeof(struct se_session), __alignof__(struct se_session),
99                         0, NULL);
100         if (!se_sess_cache) {
101                 pr_err("kmem_cache_create() for struct se_session"
102                                 " failed\n");
103                 goto out_free_tmr_req_cache;
104         }
105         se_ua_cache = kmem_cache_create("se_ua_cache",
106                         sizeof(struct se_ua), __alignof__(struct se_ua),
107                         0, NULL);
108         if (!se_ua_cache) {
109                 pr_err("kmem_cache_create() for struct se_ua failed\n");
110                 goto out_free_sess_cache;
111         }
112         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
113                         sizeof(struct t10_pr_registration),
114                         __alignof__(struct t10_pr_registration), 0, NULL);
115         if (!t10_pr_reg_cache) {
116                 pr_err("kmem_cache_create() for struct t10_pr_registration"
117                                 " failed\n");
118                 goto out_free_ua_cache;
119         }
120         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
121                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
122                         0, NULL);
123         if (!t10_alua_lu_gp_cache) {
124                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
125                                 " failed\n");
126                 goto out_free_pr_reg_cache;
127         }
128         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
129                         sizeof(struct t10_alua_lu_gp_member),
130                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
131         if (!t10_alua_lu_gp_mem_cache) {
132                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
133                                 "cache failed\n");
134                 goto out_free_lu_gp_cache;
135         }
136         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
137                         sizeof(struct t10_alua_tg_pt_gp),
138                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
139         if (!t10_alua_tg_pt_gp_cache) {
140                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
141                                 "cache failed\n");
142                 goto out_free_lu_gp_mem_cache;
143         }
144         t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
145                         "t10_alua_tg_pt_gp_mem_cache",
146                         sizeof(struct t10_alua_tg_pt_gp_member),
147                         __alignof__(struct t10_alua_tg_pt_gp_member),
148                         0, NULL);
149         if (!t10_alua_tg_pt_gp_mem_cache) {
150                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
151                                 "mem_t failed\n");
152                 goto out_free_tg_pt_gp_cache;
153         }
154
155         target_completion_wq = alloc_workqueue("target_completion",
156                                                WQ_MEM_RECLAIM, 0);
157         if (!target_completion_wq)
158                 goto out_free_tg_pt_gp_mem_cache;
159
160         return 0;
161
162 out_free_tg_pt_gp_mem_cache:
163         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
164 out_free_tg_pt_gp_cache:
165         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
166 out_free_lu_gp_mem_cache:
167         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
168 out_free_lu_gp_cache:
169         kmem_cache_destroy(t10_alua_lu_gp_cache);
170 out_free_pr_reg_cache:
171         kmem_cache_destroy(t10_pr_reg_cache);
172 out_free_ua_cache:
173         kmem_cache_destroy(se_ua_cache);
174 out_free_sess_cache:
175         kmem_cache_destroy(se_sess_cache);
176 out_free_tmr_req_cache:
177         kmem_cache_destroy(se_tmr_req_cache);
178 out:
179         return -ENOMEM;
180 }
181
182 void release_se_kmem_caches(void)
183 {
184         destroy_workqueue(target_completion_wq);
185         kmem_cache_destroy(se_tmr_req_cache);
186         kmem_cache_destroy(se_sess_cache);
187         kmem_cache_destroy(se_ua_cache);
188         kmem_cache_destroy(t10_pr_reg_cache);
189         kmem_cache_destroy(t10_alua_lu_gp_cache);
190         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
191         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
192         kmem_cache_destroy(t10_alua_tg_pt_gp_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_init_queue_obj(struct se_queue_obj *qobj)
216 {
217         atomic_set(&qobj->queue_cnt, 0);
218         INIT_LIST_HEAD(&qobj->qobj_list);
219         init_waitqueue_head(&qobj->thread_wq);
220         spin_lock_init(&qobj->cmd_queue_lock);
221 }
222 EXPORT_SYMBOL(transport_init_queue_obj);
223
224 void transport_subsystem_check_init(void)
225 {
226         int ret;
227
228         if (sub_api_initialized)
229                 return;
230
231         ret = request_module("target_core_iblock");
232         if (ret != 0)
233                 pr_err("Unable to load target_core_iblock\n");
234
235         ret = request_module("target_core_file");
236         if (ret != 0)
237                 pr_err("Unable to load target_core_file\n");
238
239         ret = request_module("target_core_pscsi");
240         if (ret != 0)
241                 pr_err("Unable to load target_core_pscsi\n");
242
243         ret = request_module("target_core_stgt");
244         if (ret != 0)
245                 pr_err("Unable to load target_core_stgt\n");
246
247         sub_api_initialized = 1;
248         return;
249 }
250
251 struct se_session *transport_init_session(void)
252 {
253         struct se_session *se_sess;
254
255         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
256         if (!se_sess) {
257                 pr_err("Unable to allocate struct se_session from"
258                                 " se_sess_cache\n");
259                 return ERR_PTR(-ENOMEM);
260         }
261         INIT_LIST_HEAD(&se_sess->sess_list);
262         INIT_LIST_HEAD(&se_sess->sess_acl_list);
263         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
264         INIT_LIST_HEAD(&se_sess->sess_wait_list);
265         spin_lock_init(&se_sess->sess_cmd_lock);
266
267         return se_sess;
268 }
269 EXPORT_SYMBOL(transport_init_session);
270
271 /*
272  * Called with spin_lock_bh(&struct se_portal_group->session_lock called.
273  */
274 void __transport_register_session(
275         struct se_portal_group *se_tpg,
276         struct se_node_acl *se_nacl,
277         struct se_session *se_sess,
278         void *fabric_sess_ptr)
279 {
280         unsigned char buf[PR_REG_ISID_LEN];
281
282         se_sess->se_tpg = se_tpg;
283         se_sess->fabric_sess_ptr = fabric_sess_ptr;
284         /*
285          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
286          *
287          * Only set for struct se_session's that will actually be moving I/O.
288          * eg: *NOT* discovery sessions.
289          */
290         if (se_nacl) {
291                 /*
292                  * If the fabric module supports an ISID based TransportID,
293                  * save this value in binary from the fabric I_T Nexus now.
294                  */
295                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
296                         memset(&buf[0], 0, PR_REG_ISID_LEN);
297                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
298                                         &buf[0], PR_REG_ISID_LEN);
299                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
300                 }
301                 spin_lock_irq(&se_nacl->nacl_sess_lock);
302                 /*
303                  * The se_nacl->nacl_sess pointer will be set to the
304                  * last active I_T Nexus for each struct se_node_acl.
305                  */
306                 se_nacl->nacl_sess = se_sess;
307
308                 list_add_tail(&se_sess->sess_acl_list,
309                               &se_nacl->acl_sess_list);
310                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
311         }
312         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
313
314         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
315                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
316 }
317 EXPORT_SYMBOL(__transport_register_session);
318
319 void transport_register_session(
320         struct se_portal_group *se_tpg,
321         struct se_node_acl *se_nacl,
322         struct se_session *se_sess,
323         void *fabric_sess_ptr)
324 {
325         spin_lock_bh(&se_tpg->session_lock);
326         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
327         spin_unlock_bh(&se_tpg->session_lock);
328 }
329 EXPORT_SYMBOL(transport_register_session);
330
331 void transport_deregister_session_configfs(struct se_session *se_sess)
332 {
333         struct se_node_acl *se_nacl;
334         unsigned long flags;
335         /*
336          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
337          */
338         se_nacl = se_sess->se_node_acl;
339         if (se_nacl) {
340                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
341                 list_del(&se_sess->sess_acl_list);
342                 /*
343                  * If the session list is empty, then clear the pointer.
344                  * Otherwise, set the struct se_session pointer from the tail
345                  * element of the per struct se_node_acl active session list.
346                  */
347                 if (list_empty(&se_nacl->acl_sess_list))
348                         se_nacl->nacl_sess = NULL;
349                 else {
350                         se_nacl->nacl_sess = container_of(
351                                         se_nacl->acl_sess_list.prev,
352                                         struct se_session, sess_acl_list);
353                 }
354                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
355         }
356 }
357 EXPORT_SYMBOL(transport_deregister_session_configfs);
358
359 void transport_free_session(struct se_session *se_sess)
360 {
361         kmem_cache_free(se_sess_cache, se_sess);
362 }
363 EXPORT_SYMBOL(transport_free_session);
364
365 void transport_deregister_session(struct se_session *se_sess)
366 {
367         struct se_portal_group *se_tpg = se_sess->se_tpg;
368         struct se_node_acl *se_nacl;
369         unsigned long flags;
370
371         if (!se_tpg) {
372                 transport_free_session(se_sess);
373                 return;
374         }
375
376         spin_lock_irqsave(&se_tpg->session_lock, flags);
377         list_del(&se_sess->sess_list);
378         se_sess->se_tpg = NULL;
379         se_sess->fabric_sess_ptr = NULL;
380         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
381
382         /*
383          * Determine if we need to do extra work for this initiator node's
384          * struct se_node_acl if it had been previously dynamically generated.
385          */
386         se_nacl = se_sess->se_node_acl;
387         if (se_nacl) {
388                 spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
389                 if (se_nacl->dynamic_node_acl) {
390                         if (!se_tpg->se_tpg_tfo->tpg_check_demo_mode_cache(
391                                         se_tpg)) {
392                                 list_del(&se_nacl->acl_list);
393                                 se_tpg->num_node_acls--;
394                                 spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
395
396                                 core_tpg_wait_for_nacl_pr_ref(se_nacl);
397                                 core_free_device_list_for_node(se_nacl, se_tpg);
398                                 se_tpg->se_tpg_tfo->tpg_release_fabric_acl(se_tpg,
399                                                 se_nacl);
400                                 spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
401                         }
402                 }
403                 spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
404         }
405
406         transport_free_session(se_sess);
407
408         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
409                 se_tpg->se_tpg_tfo->get_fabric_name());
410 }
411 EXPORT_SYMBOL(transport_deregister_session);
412
413 /*
414  * Called with cmd->t_state_lock held.
415  */
416 static void transport_all_task_dev_remove_state(struct se_cmd *cmd)
417 {
418         struct se_device *dev = cmd->se_dev;
419         struct se_task *task;
420         unsigned long flags;
421
422         if (!dev)
423                 return;
424
425         list_for_each_entry(task, &cmd->t_task_list, t_list) {
426                 if (task->task_flags & TF_ACTIVE)
427                         continue;
428
429                 if (!atomic_read(&task->task_state_active))
430                         continue;
431
432                 spin_lock_irqsave(&dev->execute_task_lock, flags);
433                 list_del(&task->t_state_list);
434                 pr_debug("Removed ITT: 0x%08x dev: %p task[%p]\n",
435                         cmd->se_tfo->get_task_tag(cmd), dev, task);
436                 spin_unlock_irqrestore(&dev->execute_task_lock, flags);
437
438                 atomic_set(&task->task_state_active, 0);
439                 atomic_dec(&cmd->t_task_cdbs_ex_left);
440         }
441 }
442
443 /*      transport_cmd_check_stop():
444  *
445  *      'transport_off = 1' determines if t_transport_active should be cleared.
446  *      'transport_off = 2' determines if task_dev_state should be removed.
447  *
448  *      A non-zero u8 t_state sets cmd->t_state.
449  *      Returns 1 when command is stopped, else 0.
450  */
451 static int transport_cmd_check_stop(
452         struct se_cmd *cmd,
453         int transport_off,
454         u8 t_state)
455 {
456         unsigned long flags;
457
458         spin_lock_irqsave(&cmd->t_state_lock, flags);
459         /*
460          * Determine if IOCTL context caller in requesting the stopping of this
461          * command for LUN shutdown purposes.
462          */
463         if (atomic_read(&cmd->transport_lun_stop)) {
464                 pr_debug("%s:%d atomic_read(&cmd->transport_lun_stop)"
465                         " == TRUE for ITT: 0x%08x\n", __func__, __LINE__,
466                         cmd->se_tfo->get_task_tag(cmd));
467
468                 atomic_set(&cmd->t_transport_active, 0);
469                 if (transport_off == 2)
470                         transport_all_task_dev_remove_state(cmd);
471                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
472
473                 complete(&cmd->transport_lun_stop_comp);
474                 return 1;
475         }
476         /*
477          * Determine if frontend context caller is requesting the stopping of
478          * this command for frontend exceptions.
479          */
480         if (atomic_read(&cmd->t_transport_stop)) {
481                 pr_debug("%s:%d atomic_read(&cmd->t_transport_stop) =="
482                         " TRUE for ITT: 0x%08x\n", __func__, __LINE__,
483                         cmd->se_tfo->get_task_tag(cmd));
484
485                 if (transport_off == 2)
486                         transport_all_task_dev_remove_state(cmd);
487
488                 /*
489                  * Clear struct se_cmd->se_lun before the transport_off == 2 handoff
490                  * to FE.
491                  */
492                 if (transport_off == 2)
493                         cmd->se_lun = NULL;
494                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
495
496                 complete(&cmd->t_transport_stop_comp);
497                 return 1;
498         }
499         if (transport_off) {
500                 atomic_set(&cmd->t_transport_active, 0);
501                 if (transport_off == 2) {
502                         transport_all_task_dev_remove_state(cmd);
503                         /*
504                          * Clear struct se_cmd->se_lun before the transport_off == 2
505                          * handoff to fabric module.
506                          */
507                         cmd->se_lun = NULL;
508                         /*
509                          * Some fabric modules like tcm_loop can release
510                          * their internally allocated I/O reference now and
511                          * struct se_cmd now.
512                          *
513                          * Fabric modules are expected to return '1' here if the
514                          * se_cmd being passed is released at this point,
515                          * or zero if not being released.
516                          */
517                         if (cmd->se_tfo->check_stop_free != NULL) {
518                                 spin_unlock_irqrestore(
519                                         &cmd->t_state_lock, flags);
520
521                                 return cmd->se_tfo->check_stop_free(cmd);
522                         }
523                 }
524                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
525
526                 return 0;
527         } else if (t_state)
528                 cmd->t_state = t_state;
529         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
530
531         return 0;
532 }
533
534 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
535 {
536         return transport_cmd_check_stop(cmd, 2, 0);
537 }
538
539 static void transport_lun_remove_cmd(struct se_cmd *cmd)
540 {
541         struct se_lun *lun = cmd->se_lun;
542         unsigned long flags;
543
544         if (!lun)
545                 return;
546
547         spin_lock_irqsave(&cmd->t_state_lock, flags);
548         if (!atomic_read(&cmd->transport_dev_active)) {
549                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
550                 goto check_lun;
551         }
552         atomic_set(&cmd->transport_dev_active, 0);
553         transport_all_task_dev_remove_state(cmd);
554         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
555
556
557 check_lun:
558         spin_lock_irqsave(&lun->lun_cmd_lock, flags);
559         if (atomic_read(&cmd->transport_lun_active)) {
560                 list_del(&cmd->se_lun_node);
561                 atomic_set(&cmd->transport_lun_active, 0);
562 #if 0
563                 pr_debug("Removed ITT: 0x%08x from LUN LIST[%d]\n"
564                         cmd->se_tfo->get_task_tag(cmd), lun->unpacked_lun);
565 #endif
566         }
567         spin_unlock_irqrestore(&lun->lun_cmd_lock, flags);
568 }
569
570 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
571 {
572         if (!cmd->se_tmr_req)
573                 transport_lun_remove_cmd(cmd);
574
575         if (transport_cmd_check_stop_to_fabric(cmd))
576                 return;
577         if (remove) {
578                 transport_remove_cmd_from_queue(cmd);
579                 transport_put_cmd(cmd);
580         }
581 }
582
583 static void transport_add_cmd_to_queue(struct se_cmd *cmd, int t_state,
584                 bool at_head)
585 {
586         struct se_device *dev = cmd->se_dev;
587         struct se_queue_obj *qobj = &dev->dev_queue_obj;
588         unsigned long flags;
589
590         if (t_state) {
591                 spin_lock_irqsave(&cmd->t_state_lock, flags);
592                 cmd->t_state = t_state;
593                 atomic_set(&cmd->t_transport_active, 1);
594                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
595         }
596
597         spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
598
599         /* If the cmd is already on the list, remove it before we add it */
600         if (!list_empty(&cmd->se_queue_node))
601                 list_del(&cmd->se_queue_node);
602         else
603                 atomic_inc(&qobj->queue_cnt);
604
605         if (at_head)
606                 list_add(&cmd->se_queue_node, &qobj->qobj_list);
607         else
608                 list_add_tail(&cmd->se_queue_node, &qobj->qobj_list);
609         atomic_set(&cmd->t_transport_queue_active, 1);
610         spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
611
612         wake_up_interruptible(&qobj->thread_wq);
613 }
614
615 static struct se_cmd *
616 transport_get_cmd_from_queue(struct se_queue_obj *qobj)
617 {
618         struct se_cmd *cmd;
619         unsigned long flags;
620
621         spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
622         if (list_empty(&qobj->qobj_list)) {
623                 spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
624                 return NULL;
625         }
626         cmd = list_first_entry(&qobj->qobj_list, struct se_cmd, se_queue_node);
627
628         atomic_set(&cmd->t_transport_queue_active, 0);
629
630         list_del_init(&cmd->se_queue_node);
631         atomic_dec(&qobj->queue_cnt);
632         spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
633
634         return cmd;
635 }
636
637 static void transport_remove_cmd_from_queue(struct se_cmd *cmd)
638 {
639         struct se_queue_obj *qobj = &cmd->se_dev->dev_queue_obj;
640         unsigned long flags;
641
642         spin_lock_irqsave(&qobj->cmd_queue_lock, flags);
643         if (!atomic_read(&cmd->t_transport_queue_active)) {
644                 spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
645                 return;
646         }
647         atomic_set(&cmd->t_transport_queue_active, 0);
648         atomic_dec(&qobj->queue_cnt);
649         list_del_init(&cmd->se_queue_node);
650         spin_unlock_irqrestore(&qobj->cmd_queue_lock, flags);
651
652         if (atomic_read(&cmd->t_transport_queue_active)) {
653                 pr_err("ITT: 0x%08x t_transport_queue_active: %d\n",
654                         cmd->se_tfo->get_task_tag(cmd),
655                         atomic_read(&cmd->t_transport_queue_active));
656         }
657 }
658
659 /*
660  * Completion function used by TCM subsystem plugins (such as FILEIO)
661  * for queueing up response from struct se_subsystem_api->do_task()
662  */
663 void transport_complete_sync_cache(struct se_cmd *cmd, int good)
664 {
665         struct se_task *task = list_entry(cmd->t_task_list.next,
666                                 struct se_task, t_list);
667
668         if (good) {
669                 cmd->scsi_status = SAM_STAT_GOOD;
670                 task->task_scsi_status = GOOD;
671         } else {
672                 task->task_scsi_status = SAM_STAT_CHECK_CONDITION;
673                 task->task_se_cmd->scsi_sense_reason =
674                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
675
676         }
677
678         transport_complete_task(task, good);
679 }
680 EXPORT_SYMBOL(transport_complete_sync_cache);
681
682 static void target_complete_failure_work(struct work_struct *work)
683 {
684         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
685
686         transport_generic_request_failure(cmd);
687 }
688
689 /*      transport_complete_task():
690  *
691  *      Called from interrupt and non interrupt context depending
692  *      on the transport plugin.
693  */
694 void transport_complete_task(struct se_task *task, int success)
695 {
696         struct se_cmd *cmd = task->task_se_cmd;
697         struct se_device *dev = cmd->se_dev;
698         unsigned long flags;
699 #if 0
700         pr_debug("task: %p CDB: 0x%02x obj_ptr: %p\n", task,
701                         cmd->t_task_cdb[0], dev);
702 #endif
703         if (dev)
704                 atomic_inc(&dev->depth_left);
705
706         spin_lock_irqsave(&cmd->t_state_lock, flags);
707         task->task_flags &= ~TF_ACTIVE;
708
709         /*
710          * See if any sense data exists, if so set the TASK_SENSE flag.
711          * Also check for any other post completion work that needs to be
712          * done by the plugins.
713          */
714         if (dev && dev->transport->transport_complete) {
715                 if (dev->transport->transport_complete(task) != 0) {
716                         cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
717                         task->task_sense = 1;
718                         success = 1;
719                 }
720         }
721
722         /*
723          * See if we are waiting for outstanding struct se_task
724          * to complete for an exception condition
725          */
726         if (task->task_flags & TF_REQUEST_STOP) {
727                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
728                 complete(&task->task_stop_comp);
729                 return;
730         }
731
732         if (!success)
733                 cmd->t_tasks_failed = 1;
734
735         /*
736          * Decrement the outstanding t_task_cdbs_left count.  The last
737          * struct se_task from struct se_cmd will complete itself into the
738          * device queue depending upon int success.
739          */
740         if (!atomic_dec_and_test(&cmd->t_task_cdbs_left)) {
741                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
742                 return;
743         }
744
745         if (cmd->t_tasks_failed) {
746                 if (!task->task_error_status) {
747                         task->task_error_status =
748                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
749                         cmd->scsi_sense_reason =
750                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
751                 }
752
753                 INIT_WORK(&cmd->work, target_complete_failure_work);
754         } else {
755                 atomic_set(&cmd->t_transport_complete, 1);
756                 INIT_WORK(&cmd->work, target_complete_ok_work);
757         }
758
759         cmd->t_state = TRANSPORT_COMPLETE;
760         atomic_set(&cmd->t_transport_active, 1);
761         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
762
763         queue_work(target_completion_wq, &cmd->work);
764 }
765 EXPORT_SYMBOL(transport_complete_task);
766
767 /*
768  * Called by transport_add_tasks_from_cmd() once a struct se_cmd's
769  * struct se_task list are ready to be added to the active execution list
770  * struct se_device
771
772  * Called with se_dev_t->execute_task_lock called.
773  */
774 static inline int transport_add_task_check_sam_attr(
775         struct se_task *task,
776         struct se_task *task_prev,
777         struct se_device *dev)
778 {
779         /*
780          * No SAM Task attribute emulation enabled, add to tail of
781          * execution queue
782          */
783         if (dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED) {
784                 list_add_tail(&task->t_execute_list, &dev->execute_task_list);
785                 return 0;
786         }
787         /*
788          * HEAD_OF_QUEUE attribute for received CDB, which means
789          * the first task that is associated with a struct se_cmd goes to
790          * head of the struct se_device->execute_task_list, and task_prev
791          * after that for each subsequent task
792          */
793         if (task->task_se_cmd->sam_task_attr == MSG_HEAD_TAG) {
794                 list_add(&task->t_execute_list,
795                                 (task_prev != NULL) ?
796                                 &task_prev->t_execute_list :
797                                 &dev->execute_task_list);
798
799                 pr_debug("Set HEAD_OF_QUEUE for task CDB: 0x%02x"
800                                 " in execution queue\n",
801                                 task->task_se_cmd->t_task_cdb[0]);
802                 return 1;
803         }
804         /*
805          * For ORDERED, SIMPLE or UNTAGGED attribute tasks once they have been
806          * transitioned from Dermant -> Active state, and are added to the end
807          * of the struct se_device->execute_task_list
808          */
809         list_add_tail(&task->t_execute_list, &dev->execute_task_list);
810         return 0;
811 }
812
813 /*      __transport_add_task_to_execute_queue():
814  *
815  *      Called with se_dev_t->execute_task_lock called.
816  */
817 static void __transport_add_task_to_execute_queue(
818         struct se_task *task,
819         struct se_task *task_prev,
820         struct se_device *dev)
821 {
822         int head_of_queue;
823
824         head_of_queue = transport_add_task_check_sam_attr(task, task_prev, dev);
825         atomic_inc(&dev->execute_tasks);
826
827         if (atomic_read(&task->task_state_active))
828                 return;
829         /*
830          * Determine if this task needs to go to HEAD_OF_QUEUE for the
831          * state list as well.  Running with SAM Task Attribute emulation
832          * will always return head_of_queue == 0 here
833          */
834         if (head_of_queue)
835                 list_add(&task->t_state_list, (task_prev) ?
836                                 &task_prev->t_state_list :
837                                 &dev->state_task_list);
838         else
839                 list_add_tail(&task->t_state_list, &dev->state_task_list);
840
841         atomic_set(&task->task_state_active, 1);
842
843         pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n",
844                 task->task_se_cmd->se_tfo->get_task_tag(task->task_se_cmd),
845                 task, dev);
846 }
847
848 static void transport_add_tasks_to_state_queue(struct se_cmd *cmd)
849 {
850         struct se_device *dev = cmd->se_dev;
851         struct se_task *task;
852         unsigned long flags;
853
854         spin_lock_irqsave(&cmd->t_state_lock, flags);
855         list_for_each_entry(task, &cmd->t_task_list, t_list) {
856                 if (atomic_read(&task->task_state_active))
857                         continue;
858
859                 spin_lock(&dev->execute_task_lock);
860                 list_add_tail(&task->t_state_list, &dev->state_task_list);
861                 atomic_set(&task->task_state_active, 1);
862
863                 pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n",
864                         task->task_se_cmd->se_tfo->get_task_tag(
865                         task->task_se_cmd), task, dev);
866
867                 spin_unlock(&dev->execute_task_lock);
868         }
869         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
870 }
871
872 static void transport_add_tasks_from_cmd(struct se_cmd *cmd)
873 {
874         struct se_device *dev = cmd->se_dev;
875         struct se_task *task, *task_prev = NULL;
876         unsigned long flags;
877
878         spin_lock_irqsave(&dev->execute_task_lock, flags);
879         list_for_each_entry(task, &cmd->t_task_list, t_list) {
880                 if (!list_empty(&task->t_execute_list))
881                         continue;
882                 /*
883                  * __transport_add_task_to_execute_queue() handles the
884                  * SAM Task Attribute emulation if enabled
885                  */
886                 __transport_add_task_to_execute_queue(task, task_prev, dev);
887                 task_prev = task;
888         }
889         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
890 }
891
892 void __transport_remove_task_from_execute_queue(struct se_task *task,
893                 struct se_device *dev)
894 {
895         list_del_init(&task->t_execute_list);
896         atomic_dec(&dev->execute_tasks);
897 }
898
899 void transport_remove_task_from_execute_queue(
900         struct se_task *task,
901         struct se_device *dev)
902 {
903         unsigned long flags;
904
905         if (WARN_ON(list_empty(&task->t_execute_list)))
906                 return;
907
908         spin_lock_irqsave(&dev->execute_task_lock, flags);
909         __transport_remove_task_from_execute_queue(task, dev);
910         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
911 }
912
913 /*
914  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
915  */
916
917 static void target_qf_do_work(struct work_struct *work)
918 {
919         struct se_device *dev = container_of(work, struct se_device,
920                                         qf_work_queue);
921         LIST_HEAD(qf_cmd_list);
922         struct se_cmd *cmd, *cmd_tmp;
923
924         spin_lock_irq(&dev->qf_cmd_lock);
925         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
926         spin_unlock_irq(&dev->qf_cmd_lock);
927
928         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
929                 list_del(&cmd->se_qf_node);
930                 atomic_dec(&dev->dev_qf_count);
931                 smp_mb__after_atomic_dec();
932
933                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
934                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
935                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
936                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
937                         : "UNKNOWN");
938
939                 transport_add_cmd_to_queue(cmd, cmd->t_state, true);
940         }
941 }
942
943 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
944 {
945         switch (cmd->data_direction) {
946         case DMA_NONE:
947                 return "NONE";
948         case DMA_FROM_DEVICE:
949                 return "READ";
950         case DMA_TO_DEVICE:
951                 return "WRITE";
952         case DMA_BIDIRECTIONAL:
953                 return "BIDI";
954         default:
955                 break;
956         }
957
958         return "UNKNOWN";
959 }
960
961 void transport_dump_dev_state(
962         struct se_device *dev,
963         char *b,
964         int *bl)
965 {
966         *bl += sprintf(b + *bl, "Status: ");
967         switch (dev->dev_status) {
968         case TRANSPORT_DEVICE_ACTIVATED:
969                 *bl += sprintf(b + *bl, "ACTIVATED");
970                 break;
971         case TRANSPORT_DEVICE_DEACTIVATED:
972                 *bl += sprintf(b + *bl, "DEACTIVATED");
973                 break;
974         case TRANSPORT_DEVICE_SHUTDOWN:
975                 *bl += sprintf(b + *bl, "SHUTDOWN");
976                 break;
977         case TRANSPORT_DEVICE_OFFLINE_ACTIVATED:
978         case TRANSPORT_DEVICE_OFFLINE_DEACTIVATED:
979                 *bl += sprintf(b + *bl, "OFFLINE");
980                 break;
981         default:
982                 *bl += sprintf(b + *bl, "UNKNOWN=%d", dev->dev_status);
983                 break;
984         }
985
986         *bl += sprintf(b + *bl, "  Execute/Left/Max Queue Depth: %d/%d/%d",
987                 atomic_read(&dev->execute_tasks), atomic_read(&dev->depth_left),
988                 dev->queue_depth);
989         *bl += sprintf(b + *bl, "  SectorSize: %u  MaxSectors: %u\n",
990                 dev->se_sub_dev->se_dev_attrib.block_size, dev->se_sub_dev->se_dev_attrib.max_sectors);
991         *bl += sprintf(b + *bl, "        ");
992 }
993
994 void transport_dump_vpd_proto_id(
995         struct t10_vpd *vpd,
996         unsigned char *p_buf,
997         int p_buf_len)
998 {
999         unsigned char buf[VPD_TMP_BUF_SIZE];
1000         int len;
1001
1002         memset(buf, 0, VPD_TMP_BUF_SIZE);
1003         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
1004
1005         switch (vpd->protocol_identifier) {
1006         case 0x00:
1007                 sprintf(buf+len, "Fibre Channel\n");
1008                 break;
1009         case 0x10:
1010                 sprintf(buf+len, "Parallel SCSI\n");
1011                 break;
1012         case 0x20:
1013                 sprintf(buf+len, "SSA\n");
1014                 break;
1015         case 0x30:
1016                 sprintf(buf+len, "IEEE 1394\n");
1017                 break;
1018         case 0x40:
1019                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
1020                                 " Protocol\n");
1021                 break;
1022         case 0x50:
1023                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
1024                 break;
1025         case 0x60:
1026                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
1027                 break;
1028         case 0x70:
1029                 sprintf(buf+len, "Automation/Drive Interface Transport"
1030                                 " Protocol\n");
1031                 break;
1032         case 0x80:
1033                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
1034                 break;
1035         default:
1036                 sprintf(buf+len, "Unknown 0x%02x\n",
1037                                 vpd->protocol_identifier);
1038                 break;
1039         }
1040
1041         if (p_buf)
1042                 strncpy(p_buf, buf, p_buf_len);
1043         else
1044                 pr_debug("%s", buf);
1045 }
1046
1047 void
1048 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1049 {
1050         /*
1051          * Check if the Protocol Identifier Valid (PIV) bit is set..
1052          *
1053          * from spc3r23.pdf section 7.5.1
1054          */
1055          if (page_83[1] & 0x80) {
1056                 vpd->protocol_identifier = (page_83[0] & 0xf0);
1057                 vpd->protocol_identifier_set = 1;
1058                 transport_dump_vpd_proto_id(vpd, NULL, 0);
1059         }
1060 }
1061 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1062
1063 int transport_dump_vpd_assoc(
1064         struct t10_vpd *vpd,
1065         unsigned char *p_buf,
1066         int p_buf_len)
1067 {
1068         unsigned char buf[VPD_TMP_BUF_SIZE];
1069         int ret = 0;
1070         int len;
1071
1072         memset(buf, 0, VPD_TMP_BUF_SIZE);
1073         len = sprintf(buf, "T10 VPD Identifier Association: ");
1074
1075         switch (vpd->association) {
1076         case 0x00:
1077                 sprintf(buf+len, "addressed logical unit\n");
1078                 break;
1079         case 0x10:
1080                 sprintf(buf+len, "target port\n");
1081                 break;
1082         case 0x20:
1083                 sprintf(buf+len, "SCSI target device\n");
1084                 break;
1085         default:
1086                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1087                 ret = -EINVAL;
1088                 break;
1089         }
1090
1091         if (p_buf)
1092                 strncpy(p_buf, buf, p_buf_len);
1093         else
1094                 pr_debug("%s", buf);
1095
1096         return ret;
1097 }
1098
1099 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1100 {
1101         /*
1102          * The VPD identification association..
1103          *
1104          * from spc3r23.pdf Section 7.6.3.1 Table 297
1105          */
1106         vpd->association = (page_83[1] & 0x30);
1107         return transport_dump_vpd_assoc(vpd, NULL, 0);
1108 }
1109 EXPORT_SYMBOL(transport_set_vpd_assoc);
1110
1111 int transport_dump_vpd_ident_type(
1112         struct t10_vpd *vpd,
1113         unsigned char *p_buf,
1114         int p_buf_len)
1115 {
1116         unsigned char buf[VPD_TMP_BUF_SIZE];
1117         int ret = 0;
1118         int len;
1119
1120         memset(buf, 0, VPD_TMP_BUF_SIZE);
1121         len = sprintf(buf, "T10 VPD Identifier Type: ");
1122
1123         switch (vpd->device_identifier_type) {
1124         case 0x00:
1125                 sprintf(buf+len, "Vendor specific\n");
1126                 break;
1127         case 0x01:
1128                 sprintf(buf+len, "T10 Vendor ID based\n");
1129                 break;
1130         case 0x02:
1131                 sprintf(buf+len, "EUI-64 based\n");
1132                 break;
1133         case 0x03:
1134                 sprintf(buf+len, "NAA\n");
1135                 break;
1136         case 0x04:
1137                 sprintf(buf+len, "Relative target port identifier\n");
1138                 break;
1139         case 0x08:
1140                 sprintf(buf+len, "SCSI name string\n");
1141                 break;
1142         default:
1143                 sprintf(buf+len, "Unsupported: 0x%02x\n",
1144                                 vpd->device_identifier_type);
1145                 ret = -EINVAL;
1146                 break;
1147         }
1148
1149         if (p_buf) {
1150                 if (p_buf_len < strlen(buf)+1)
1151                         return -EINVAL;
1152                 strncpy(p_buf, buf, p_buf_len);
1153         } else {
1154                 pr_debug("%s", buf);
1155         }
1156
1157         return ret;
1158 }
1159
1160 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1161 {
1162         /*
1163          * The VPD identifier type..
1164          *
1165          * from spc3r23.pdf Section 7.6.3.1 Table 298
1166          */
1167         vpd->device_identifier_type = (page_83[1] & 0x0f);
1168         return transport_dump_vpd_ident_type(vpd, NULL, 0);
1169 }
1170 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1171
1172 int transport_dump_vpd_ident(
1173         struct t10_vpd *vpd,
1174         unsigned char *p_buf,
1175         int p_buf_len)
1176 {
1177         unsigned char buf[VPD_TMP_BUF_SIZE];
1178         int ret = 0;
1179
1180         memset(buf, 0, VPD_TMP_BUF_SIZE);
1181
1182         switch (vpd->device_identifier_code_set) {
1183         case 0x01: /* Binary */
1184                 sprintf(buf, "T10 VPD Binary Device Identifier: %s\n",
1185                         &vpd->device_identifier[0]);
1186                 break;
1187         case 0x02: /* ASCII */
1188                 sprintf(buf, "T10 VPD ASCII Device Identifier: %s\n",
1189                         &vpd->device_identifier[0]);
1190                 break;
1191         case 0x03: /* UTF-8 */
1192                 sprintf(buf, "T10 VPD UTF-8 Device Identifier: %s\n",
1193                         &vpd->device_identifier[0]);
1194                 break;
1195         default:
1196                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1197                         " 0x%02x", vpd->device_identifier_code_set);
1198                 ret = -EINVAL;
1199                 break;
1200         }
1201
1202         if (p_buf)
1203                 strncpy(p_buf, buf, p_buf_len);
1204         else
1205                 pr_debug("%s", buf);
1206
1207         return ret;
1208 }
1209
1210 int
1211 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1212 {
1213         static const char hex_str[] = "0123456789abcdef";
1214         int j = 0, i = 4; /* offset to start of the identifer */
1215
1216         /*
1217          * The VPD Code Set (encoding)
1218          *
1219          * from spc3r23.pdf Section 7.6.3.1 Table 296
1220          */
1221         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1222         switch (vpd->device_identifier_code_set) {
1223         case 0x01: /* Binary */
1224                 vpd->device_identifier[j++] =
1225                                 hex_str[vpd->device_identifier_type];
1226                 while (i < (4 + page_83[3])) {
1227                         vpd->device_identifier[j++] =
1228                                 hex_str[(page_83[i] & 0xf0) >> 4];
1229                         vpd->device_identifier[j++] =
1230                                 hex_str[page_83[i] & 0x0f];
1231                         i++;
1232                 }
1233                 break;
1234         case 0x02: /* ASCII */
1235         case 0x03: /* UTF-8 */
1236                 while (i < (4 + page_83[3]))
1237                         vpd->device_identifier[j++] = page_83[i++];
1238                 break;
1239         default:
1240                 break;
1241         }
1242
1243         return transport_dump_vpd_ident(vpd, NULL, 0);
1244 }
1245 EXPORT_SYMBOL(transport_set_vpd_ident);
1246
1247 static void core_setup_task_attr_emulation(struct se_device *dev)
1248 {
1249         /*
1250          * If this device is from Target_Core_Mod/pSCSI, disable the
1251          * SAM Task Attribute emulation.
1252          *
1253          * This is currently not available in upsream Linux/SCSI Target
1254          * mode code, and is assumed to be disabled while using TCM/pSCSI.
1255          */
1256         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) {
1257                 dev->dev_task_attr_type = SAM_TASK_ATTR_PASSTHROUGH;
1258                 return;
1259         }
1260
1261         dev->dev_task_attr_type = SAM_TASK_ATTR_EMULATED;
1262         pr_debug("%s: Using SAM_TASK_ATTR_EMULATED for SPC: 0x%02x"
1263                 " device\n", dev->transport->name,
1264                 dev->transport->get_device_rev(dev));
1265 }
1266
1267 static void scsi_dump_inquiry(struct se_device *dev)
1268 {
1269         struct t10_wwn *wwn = &dev->se_sub_dev->t10_wwn;
1270         int i, device_type;
1271         /*
1272          * Print Linux/SCSI style INQUIRY formatting to the kernel ring buffer
1273          */
1274         pr_debug("  Vendor: ");
1275         for (i = 0; i < 8; i++)
1276                 if (wwn->vendor[i] >= 0x20)
1277                         pr_debug("%c", wwn->vendor[i]);
1278                 else
1279                         pr_debug(" ");
1280
1281         pr_debug("  Model: ");
1282         for (i = 0; i < 16; i++)
1283                 if (wwn->model[i] >= 0x20)
1284                         pr_debug("%c", wwn->model[i]);
1285                 else
1286                         pr_debug(" ");
1287
1288         pr_debug("  Revision: ");
1289         for (i = 0; i < 4; i++)
1290                 if (wwn->revision[i] >= 0x20)
1291                         pr_debug("%c", wwn->revision[i]);
1292                 else
1293                         pr_debug(" ");
1294
1295         pr_debug("\n");
1296
1297         device_type = dev->transport->get_device_type(dev);
1298         pr_debug("  Type:   %s ", scsi_device_type(device_type));
1299         pr_debug("                 ANSI SCSI revision: %02x\n",
1300                                 dev->transport->get_device_rev(dev));
1301 }
1302
1303 struct se_device *transport_add_device_to_core_hba(
1304         struct se_hba *hba,
1305         struct se_subsystem_api *transport,
1306         struct se_subsystem_dev *se_dev,
1307         u32 device_flags,
1308         void *transport_dev,
1309         struct se_dev_limits *dev_limits,
1310         const char *inquiry_prod,
1311         const char *inquiry_rev)
1312 {
1313         int force_pt;
1314         struct se_device  *dev;
1315
1316         dev = kzalloc(sizeof(struct se_device), GFP_KERNEL);
1317         if (!dev) {
1318                 pr_err("Unable to allocate memory for se_dev_t\n");
1319                 return NULL;
1320         }
1321
1322         transport_init_queue_obj(&dev->dev_queue_obj);
1323         dev->dev_flags          = device_flags;
1324         dev->dev_status         |= TRANSPORT_DEVICE_DEACTIVATED;
1325         dev->dev_ptr            = transport_dev;
1326         dev->se_hba             = hba;
1327         dev->se_sub_dev         = se_dev;
1328         dev->transport          = transport;
1329         atomic_set(&dev->active_cmds, 0);
1330         INIT_LIST_HEAD(&dev->dev_list);
1331         INIT_LIST_HEAD(&dev->dev_sep_list);
1332         INIT_LIST_HEAD(&dev->dev_tmr_list);
1333         INIT_LIST_HEAD(&dev->execute_task_list);
1334         INIT_LIST_HEAD(&dev->delayed_cmd_list);
1335         INIT_LIST_HEAD(&dev->state_task_list);
1336         INIT_LIST_HEAD(&dev->qf_cmd_list);
1337         spin_lock_init(&dev->execute_task_lock);
1338         spin_lock_init(&dev->delayed_cmd_lock);
1339         spin_lock_init(&dev->state_task_lock);
1340         spin_lock_init(&dev->dev_alua_lock);
1341         spin_lock_init(&dev->dev_reservation_lock);
1342         spin_lock_init(&dev->dev_status_lock);
1343         spin_lock_init(&dev->dev_status_thr_lock);
1344         spin_lock_init(&dev->se_port_lock);
1345         spin_lock_init(&dev->se_tmr_lock);
1346         spin_lock_init(&dev->qf_cmd_lock);
1347
1348         dev->queue_depth        = dev_limits->queue_depth;
1349         atomic_set(&dev->depth_left, dev->queue_depth);
1350         atomic_set(&dev->dev_ordered_id, 0);
1351
1352         se_dev_set_default_attribs(dev, dev_limits);
1353
1354         dev->dev_index = scsi_get_new_index(SCSI_DEVICE_INDEX);
1355         dev->creation_time = get_jiffies_64();
1356         spin_lock_init(&dev->stats_lock);
1357
1358         spin_lock(&hba->device_lock);
1359         list_add_tail(&dev->dev_list, &hba->hba_dev_list);
1360         hba->dev_count++;
1361         spin_unlock(&hba->device_lock);
1362         /*
1363          * Setup the SAM Task Attribute emulation for struct se_device
1364          */
1365         core_setup_task_attr_emulation(dev);
1366         /*
1367          * Force PR and ALUA passthrough emulation with internal object use.
1368          */
1369         force_pt = (hba->hba_flags & HBA_FLAGS_INTERNAL_USE);
1370         /*
1371          * Setup the Reservations infrastructure for struct se_device
1372          */
1373         core_setup_reservations(dev, force_pt);
1374         /*
1375          * Setup the Asymmetric Logical Unit Assignment for struct se_device
1376          */
1377         if (core_setup_alua(dev, force_pt) < 0)
1378                 goto out;
1379
1380         /*
1381          * Startup the struct se_device processing thread
1382          */
1383         dev->process_thread = kthread_run(transport_processing_thread, dev,
1384                                           "LIO_%s", dev->transport->name);
1385         if (IS_ERR(dev->process_thread)) {
1386                 pr_err("Unable to create kthread: LIO_%s\n",
1387                         dev->transport->name);
1388                 goto out;
1389         }
1390         /*
1391          * Setup work_queue for QUEUE_FULL
1392          */
1393         INIT_WORK(&dev->qf_work_queue, target_qf_do_work);
1394         /*
1395          * Preload the initial INQUIRY const values if we are doing
1396          * anything virtual (IBLOCK, FILEIO, RAMDISK), but not for TCM/pSCSI
1397          * passthrough because this is being provided by the backend LLD.
1398          * This is required so that transport_get_inquiry() copies these
1399          * originals once back into DEV_T10_WWN(dev) for the virtual device
1400          * setup.
1401          */
1402         if (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) {
1403                 if (!inquiry_prod || !inquiry_rev) {
1404                         pr_err("All non TCM/pSCSI plugins require"
1405                                 " INQUIRY consts\n");
1406                         goto out;
1407                 }
1408
1409                 strncpy(&dev->se_sub_dev->t10_wwn.vendor[0], "LIO-ORG", 8);
1410                 strncpy(&dev->se_sub_dev->t10_wwn.model[0], inquiry_prod, 16);
1411                 strncpy(&dev->se_sub_dev->t10_wwn.revision[0], inquiry_rev, 4);
1412         }
1413         scsi_dump_inquiry(dev);
1414
1415         return dev;
1416 out:
1417         kthread_stop(dev->process_thread);
1418
1419         spin_lock(&hba->device_lock);
1420         list_del(&dev->dev_list);
1421         hba->dev_count--;
1422         spin_unlock(&hba->device_lock);
1423
1424         se_release_vpd_for_dev(dev);
1425
1426         kfree(dev);
1427
1428         return NULL;
1429 }
1430 EXPORT_SYMBOL(transport_add_device_to_core_hba);
1431
1432 /*      transport_generic_prepare_cdb():
1433  *
1434  *      Since the Initiator sees iSCSI devices as LUNs,  the SCSI CDB will
1435  *      contain the iSCSI LUN in bits 7-5 of byte 1 as per SAM-2.
1436  *      The point of this is since we are mapping iSCSI LUNs to
1437  *      SCSI Target IDs having a non-zero LUN in the CDB will throw the
1438  *      devices and HBAs for a loop.
1439  */
1440 static inline void transport_generic_prepare_cdb(
1441         unsigned char *cdb)
1442 {
1443         switch (cdb[0]) {
1444         case READ_10: /* SBC - RDProtect */
1445         case READ_12: /* SBC - RDProtect */
1446         case READ_16: /* SBC - RDProtect */
1447         case SEND_DIAGNOSTIC: /* SPC - SELF-TEST Code */
1448         case VERIFY: /* SBC - VRProtect */
1449         case VERIFY_16: /* SBC - VRProtect */
1450         case WRITE_VERIFY: /* SBC - VRProtect */
1451         case WRITE_VERIFY_12: /* SBC - VRProtect */
1452                 break;
1453         default:
1454                 cdb[1] &= 0x1f; /* clear logical unit number */
1455                 break;
1456         }
1457 }
1458
1459 static struct se_task *
1460 transport_generic_get_task(struct se_cmd *cmd,
1461                 enum dma_data_direction data_direction)
1462 {
1463         struct se_task *task;
1464         struct se_device *dev = cmd->se_dev;
1465
1466         task = dev->transport->alloc_task(cmd->t_task_cdb);
1467         if (!task) {
1468                 pr_err("Unable to allocate struct se_task\n");
1469                 return NULL;
1470         }
1471
1472         INIT_LIST_HEAD(&task->t_list);
1473         INIT_LIST_HEAD(&task->t_execute_list);
1474         INIT_LIST_HEAD(&task->t_state_list);
1475         init_completion(&task->task_stop_comp);
1476         task->task_se_cmd = cmd;
1477         task->task_data_direction = data_direction;
1478
1479         return task;
1480 }
1481
1482 static int transport_generic_cmd_sequencer(struct se_cmd *, unsigned char *);
1483
1484 /*
1485  * Used by fabric modules containing a local struct se_cmd within their
1486  * fabric dependent per I/O descriptor.
1487  */
1488 void transport_init_se_cmd(
1489         struct se_cmd *cmd,
1490         struct target_core_fabric_ops *tfo,
1491         struct se_session *se_sess,
1492         u32 data_length,
1493         int data_direction,
1494         int task_attr,
1495         unsigned char *sense_buffer)
1496 {
1497         INIT_LIST_HEAD(&cmd->se_lun_node);
1498         INIT_LIST_HEAD(&cmd->se_delayed_node);
1499         INIT_LIST_HEAD(&cmd->se_qf_node);
1500         INIT_LIST_HEAD(&cmd->se_queue_node);
1501         INIT_LIST_HEAD(&cmd->se_cmd_list);
1502         INIT_LIST_HEAD(&cmd->t_task_list);
1503         init_completion(&cmd->transport_lun_fe_stop_comp);
1504         init_completion(&cmd->transport_lun_stop_comp);
1505         init_completion(&cmd->t_transport_stop_comp);
1506         init_completion(&cmd->cmd_wait_comp);
1507         spin_lock_init(&cmd->t_state_lock);
1508         atomic_set(&cmd->transport_dev_active, 1);
1509
1510         cmd->se_tfo = tfo;
1511         cmd->se_sess = se_sess;
1512         cmd->data_length = data_length;
1513         cmd->data_direction = data_direction;
1514         cmd->sam_task_attr = task_attr;
1515         cmd->sense_buffer = sense_buffer;
1516 }
1517 EXPORT_SYMBOL(transport_init_se_cmd);
1518
1519 static int transport_check_alloc_task_attr(struct se_cmd *cmd)
1520 {
1521         /*
1522          * Check if SAM Task Attribute emulation is enabled for this
1523          * struct se_device storage object
1524          */
1525         if (cmd->se_dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED)
1526                 return 0;
1527
1528         if (cmd->sam_task_attr == MSG_ACA_TAG) {
1529                 pr_debug("SAM Task Attribute ACA"
1530                         " emulation is not supported\n");
1531                 return -EINVAL;
1532         }
1533         /*
1534          * Used to determine when ORDERED commands should go from
1535          * Dormant to Active status.
1536          */
1537         cmd->se_ordered_id = atomic_inc_return(&cmd->se_dev->dev_ordered_id);
1538         smp_mb__after_atomic_inc();
1539         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1540                         cmd->se_ordered_id, cmd->sam_task_attr,
1541                         cmd->se_dev->transport->name);
1542         return 0;
1543 }
1544
1545 /*      transport_generic_allocate_tasks():
1546  *
1547  *      Called from fabric RX Thread.
1548  */
1549 int transport_generic_allocate_tasks(
1550         struct se_cmd *cmd,
1551         unsigned char *cdb)
1552 {
1553         int ret;
1554
1555         transport_generic_prepare_cdb(cdb);
1556         /*
1557          * Ensure that the received CDB is less than the max (252 + 8) bytes
1558          * for VARIABLE_LENGTH_CMD
1559          */
1560         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1561                 pr_err("Received SCSI CDB with command_size: %d that"
1562                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1563                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1564                 cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1565                 cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
1566                 return -EINVAL;
1567         }
1568         /*
1569          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1570          * allocate the additional extended CDB buffer now..  Otherwise
1571          * setup the pointer from __t_task_cdb to t_task_cdb.
1572          */
1573         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1574                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1575                                                 GFP_KERNEL);
1576                 if (!cmd->t_task_cdb) {
1577                         pr_err("Unable to allocate cmd->t_task_cdb"
1578                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1579                                 scsi_command_size(cdb),
1580                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1581                         cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1582                         cmd->scsi_sense_reason =
1583                                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1584                         return -ENOMEM;
1585                 }
1586         } else
1587                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1588         /*
1589          * Copy the original CDB into cmd->
1590          */
1591         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1592         /*
1593          * Setup the received CDB based on SCSI defined opcodes and
1594          * perform unit attention, persistent reservations and ALUA
1595          * checks for virtual device backends.  The cmd->t_task_cdb
1596          * pointer is expected to be setup before we reach this point.
1597          */
1598         ret = transport_generic_cmd_sequencer(cmd, cdb);
1599         if (ret < 0)
1600                 return ret;
1601         /*
1602          * Check for SAM Task Attribute Emulation
1603          */
1604         if (transport_check_alloc_task_attr(cmd) < 0) {
1605                 cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1606                 cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
1607                 return -EINVAL;
1608         }
1609         spin_lock(&cmd->se_lun->lun_sep_lock);
1610         if (cmd->se_lun->lun_sep)
1611                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1612         spin_unlock(&cmd->se_lun->lun_sep_lock);
1613         return 0;
1614 }
1615 EXPORT_SYMBOL(transport_generic_allocate_tasks);
1616
1617 /*
1618  * Used by fabric module frontends to queue tasks directly.
1619  * Many only be used from process context only
1620  */
1621 int transport_handle_cdb_direct(
1622         struct se_cmd *cmd)
1623 {
1624         int ret;
1625
1626         if (!cmd->se_lun) {
1627                 dump_stack();
1628                 pr_err("cmd->se_lun is NULL\n");
1629                 return -EINVAL;
1630         }
1631         if (in_interrupt()) {
1632                 dump_stack();
1633                 pr_err("transport_generic_handle_cdb cannot be called"
1634                                 " from interrupt context\n");
1635                 return -EINVAL;
1636         }
1637         /*
1638          * Set TRANSPORT_NEW_CMD state and cmd->t_transport_active=1 following
1639          * transport_generic_handle_cdb*() -> transport_add_cmd_to_queue()
1640          * in existing usage to ensure that outstanding descriptors are handled
1641          * correctly during shutdown via transport_wait_for_tasks()
1642          *
1643          * Also, we don't take cmd->t_state_lock here as we only expect
1644          * this to be called for initial descriptor submission.
1645          */
1646         cmd->t_state = TRANSPORT_NEW_CMD;
1647         atomic_set(&cmd->t_transport_active, 1);
1648         /*
1649          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1650          * so follow TRANSPORT_NEW_CMD processing thread context usage
1651          * and call transport_generic_request_failure() if necessary..
1652          */
1653         ret = transport_generic_new_cmd(cmd);
1654         if (ret < 0)
1655                 transport_generic_request_failure(cmd);
1656
1657         return 0;
1658 }
1659 EXPORT_SYMBOL(transport_handle_cdb_direct);
1660
1661 /*
1662  * Used by fabric module frontends defining a TFO->new_cmd_map() caller
1663  * to  queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD_MAP in order to
1664  * complete setup in TCM process context w/ TFO->new_cmd_map().
1665  */
1666 int transport_generic_handle_cdb_map(
1667         struct se_cmd *cmd)
1668 {
1669         if (!cmd->se_lun) {
1670                 dump_stack();
1671                 pr_err("cmd->se_lun is NULL\n");
1672                 return -EINVAL;
1673         }
1674
1675         transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD_MAP, false);
1676         return 0;
1677 }
1678 EXPORT_SYMBOL(transport_generic_handle_cdb_map);
1679
1680 /*      transport_generic_handle_data():
1681  *
1682  *
1683  */
1684 int transport_generic_handle_data(
1685         struct se_cmd *cmd)
1686 {
1687         /*
1688          * For the software fabric case, then we assume the nexus is being
1689          * failed/shutdown when signals are pending from the kthread context
1690          * caller, so we return a failure.  For the HW target mode case running
1691          * in interrupt code, the signal_pending() check is skipped.
1692          */
1693         if (!in_interrupt() && signal_pending(current))
1694                 return -EPERM;
1695         /*
1696          * If the received CDB has aleady been ABORTED by the generic
1697          * target engine, we now call transport_check_aborted_status()
1698          * to queue any delated TASK_ABORTED status for the received CDB to the
1699          * fabric module as we are expecting no further incoming DATA OUT
1700          * sequences at this point.
1701          */
1702         if (transport_check_aborted_status(cmd, 1) != 0)
1703                 return 0;
1704
1705         transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_WRITE, false);
1706         return 0;
1707 }
1708 EXPORT_SYMBOL(transport_generic_handle_data);
1709
1710 /*      transport_generic_handle_tmr():
1711  *
1712  *
1713  */
1714 int transport_generic_handle_tmr(
1715         struct se_cmd *cmd)
1716 {
1717         transport_add_cmd_to_queue(cmd, TRANSPORT_PROCESS_TMR, false);
1718         return 0;
1719 }
1720 EXPORT_SYMBOL(transport_generic_handle_tmr);
1721
1722 /*
1723  * If the task is active, request it to be stopped and sleep until it
1724  * has completed.
1725  */
1726 bool target_stop_task(struct se_task *task, unsigned long *flags)
1727 {
1728         struct se_cmd *cmd = task->task_se_cmd;
1729         bool was_active = false;
1730
1731         if (task->task_flags & TF_ACTIVE) {
1732                 task->task_flags |= TF_REQUEST_STOP;
1733                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1734
1735                 pr_debug("Task %p waiting to complete\n", task);
1736                 wait_for_completion(&task->task_stop_comp);
1737                 pr_debug("Task %p stopped successfully\n", task);
1738
1739                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1740                 atomic_dec(&cmd->t_task_cdbs_left);
1741                 task->task_flags &= ~(TF_ACTIVE | TF_REQUEST_STOP);
1742                 was_active = true;
1743         }
1744
1745         return was_active;
1746 }
1747
1748 static int transport_stop_tasks_for_cmd(struct se_cmd *cmd)
1749 {
1750         struct se_task *task, *task_tmp;
1751         unsigned long flags;
1752         int ret = 0;
1753
1754         pr_debug("ITT[0x%08x] - Stopping tasks\n",
1755                 cmd->se_tfo->get_task_tag(cmd));
1756
1757         /*
1758          * No tasks remain in the execution queue
1759          */
1760         spin_lock_irqsave(&cmd->t_state_lock, flags);
1761         list_for_each_entry_safe(task, task_tmp,
1762                                 &cmd->t_task_list, t_list) {
1763                 pr_debug("Processing task %p\n", task);
1764                 /*
1765                  * If the struct se_task has not been sent and is not active,
1766                  * remove the struct se_task from the execution queue.
1767                  */
1768                 if (!(task->task_flags & (TF_ACTIVE | TF_SENT))) {
1769                         spin_unlock_irqrestore(&cmd->t_state_lock,
1770                                         flags);
1771                         transport_remove_task_from_execute_queue(task,
1772                                         cmd->se_dev);
1773
1774                         pr_debug("Task %p removed from execute queue\n", task);
1775                         spin_lock_irqsave(&cmd->t_state_lock, flags);
1776                         continue;
1777                 }
1778
1779                 if (!target_stop_task(task, &flags)) {
1780                         pr_debug("Task %p - did nothing\n", task);
1781                         ret++;
1782                 }
1783         }
1784         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1785
1786         return ret;
1787 }
1788
1789 /*
1790  * Handle SAM-esque emulation for generic transport request failures.
1791  */
1792 static void transport_generic_request_failure(struct se_cmd *cmd)
1793 {
1794         int ret = 0;
1795
1796         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1797                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1798                 cmd->t_task_cdb[0]);
1799         pr_debug("-----[ i_state: %d t_state: %d scsi_sense_reason: %d\n",
1800                 cmd->se_tfo->get_cmd_state(cmd),
1801                 cmd->t_state, cmd->scsi_sense_reason);
1802         pr_debug("-----[ t_tasks: %d t_task_cdbs_left: %d"
1803                 " t_task_cdbs_sent: %d t_task_cdbs_ex_left: %d --"
1804                 " t_transport_active: %d t_transport_stop: %d"
1805                 " t_transport_sent: %d\n", cmd->t_task_list_num,
1806                 atomic_read(&cmd->t_task_cdbs_left),
1807                 atomic_read(&cmd->t_task_cdbs_sent),
1808                 atomic_read(&cmd->t_task_cdbs_ex_left),
1809                 atomic_read(&cmd->t_transport_active),
1810                 atomic_read(&cmd->t_transport_stop),
1811                 atomic_read(&cmd->t_transport_sent));
1812
1813         /*
1814          * For SAM Task Attribute emulation for failed struct se_cmd
1815          */
1816         if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
1817                 transport_complete_task_attr(cmd);
1818
1819         switch (cmd->scsi_sense_reason) {
1820         case TCM_NON_EXISTENT_LUN:
1821         case TCM_UNSUPPORTED_SCSI_OPCODE:
1822         case TCM_INVALID_CDB_FIELD:
1823         case TCM_INVALID_PARAMETER_LIST:
1824         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1825         case TCM_UNKNOWN_MODE_PAGE:
1826         case TCM_WRITE_PROTECTED:
1827         case TCM_CHECK_CONDITION_ABORT_CMD:
1828         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1829         case TCM_CHECK_CONDITION_NOT_READY:
1830                 break;
1831         case TCM_RESERVATION_CONFLICT:
1832                 /*
1833                  * No SENSE Data payload for this case, set SCSI Status
1834                  * and queue the response to $FABRIC_MOD.
1835                  *
1836                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1837                  */
1838                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1839                 /*
1840                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1841                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1842                  * CONFLICT STATUS.
1843                  *
1844                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1845                  */
1846                 if (cmd->se_sess &&
1847                     cmd->se_dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl == 2)
1848                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1849                                 cmd->orig_fe_lun, 0x2C,
1850                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1851
1852                 ret = cmd->se_tfo->queue_status(cmd);
1853                 if (ret == -EAGAIN || ret == -ENOMEM)
1854                         goto queue_full;
1855                 goto check_stop;
1856         default:
1857                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1858                         cmd->t_task_cdb[0], cmd->scsi_sense_reason);
1859                 cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1860                 break;
1861         }
1862         /*
1863          * If a fabric does not define a cmd->se_tfo->new_cmd_map caller,
1864          * make the call to transport_send_check_condition_and_sense()
1865          * directly.  Otherwise expect the fabric to make the call to
1866          * transport_send_check_condition_and_sense() after handling
1867          * possible unsoliticied write data payloads.
1868          */
1869         ret = transport_send_check_condition_and_sense(cmd,
1870                         cmd->scsi_sense_reason, 0);
1871         if (ret == -EAGAIN || ret == -ENOMEM)
1872                 goto queue_full;
1873
1874 check_stop:
1875         transport_lun_remove_cmd(cmd);
1876         if (!transport_cmd_check_stop_to_fabric(cmd))
1877                 ;
1878         return;
1879
1880 queue_full:
1881         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1882         transport_handle_queue_full(cmd, cmd->se_dev);
1883 }
1884
1885 static inline u32 transport_lba_21(unsigned char *cdb)
1886 {
1887         return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
1888 }
1889
1890 static inline u32 transport_lba_32(unsigned char *cdb)
1891 {
1892         return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
1893 }
1894
1895 static inline unsigned long long transport_lba_64(unsigned char *cdb)
1896 {
1897         unsigned int __v1, __v2;
1898
1899         __v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
1900         __v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
1901
1902         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
1903 }
1904
1905 /*
1906  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
1907  */
1908 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
1909 {
1910         unsigned int __v1, __v2;
1911
1912         __v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
1913         __v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
1914
1915         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
1916 }
1917
1918 static void transport_set_supported_SAM_opcode(struct se_cmd *se_cmd)
1919 {
1920         unsigned long flags;
1921
1922         spin_lock_irqsave(&se_cmd->t_state_lock, flags);
1923         se_cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1924         spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
1925 }
1926
1927 static inline int transport_tcq_window_closed(struct se_device *dev)
1928 {
1929         if (dev->dev_tcq_window_closed++ <
1930                         PYX_TRANSPORT_WINDOW_CLOSED_THRESHOLD) {
1931                 msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_SHORT);
1932         } else
1933                 msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_LONG);
1934
1935         wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
1936         return 0;
1937 }
1938
1939 /*
1940  * Called from Fabric Module context from transport_execute_tasks()
1941  *
1942  * The return of this function determins if the tasks from struct se_cmd
1943  * get added to the execution queue in transport_execute_tasks(),
1944  * or are added to the delayed or ordered lists here.
1945  */
1946 static inline int transport_execute_task_attr(struct se_cmd *cmd)
1947 {
1948         if (cmd->se_dev->dev_task_attr_type != SAM_TASK_ATTR_EMULATED)
1949                 return 1;
1950         /*
1951          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1952          * to allow the passed struct se_cmd list of tasks to the front of the list.
1953          */
1954          if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1955                 atomic_inc(&cmd->se_dev->dev_hoq_count);
1956                 smp_mb__after_atomic_inc();
1957                 pr_debug("Added HEAD_OF_QUEUE for CDB:"
1958                         " 0x%02x, se_ordered_id: %u\n",
1959                         cmd->t_task_cdb[0],
1960                         cmd->se_ordered_id);
1961                 return 1;
1962         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1963                 atomic_inc(&cmd->se_dev->dev_ordered_sync);
1964                 smp_mb__after_atomic_inc();
1965
1966                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered"
1967                                 " list, se_ordered_id: %u\n",
1968                                 cmd->t_task_cdb[0],
1969                                 cmd->se_ordered_id);
1970                 /*
1971                  * Add ORDERED command to tail of execution queue if
1972                  * no other older commands exist that need to be
1973                  * completed first.
1974                  */
1975                 if (!atomic_read(&cmd->se_dev->simple_cmds))
1976                         return 1;
1977         } else {
1978                 /*
1979                  * For SIMPLE and UNTAGGED Task Attribute commands
1980                  */
1981                 atomic_inc(&cmd->se_dev->simple_cmds);
1982                 smp_mb__after_atomic_inc();
1983         }
1984         /*
1985          * Otherwise if one or more outstanding ORDERED task attribute exist,
1986          * add the dormant task(s) built for the passed struct se_cmd to the
1987          * execution queue and become in Active state for this struct se_device.
1988          */
1989         if (atomic_read(&cmd->se_dev->dev_ordered_sync) != 0) {
1990                 /*
1991                  * Otherwise, add cmd w/ tasks to delayed cmd queue that
1992                  * will be drained upon completion of HEAD_OF_QUEUE task.
1993                  */
1994                 spin_lock(&cmd->se_dev->delayed_cmd_lock);
1995                 cmd->se_cmd_flags |= SCF_DELAYED_CMD_FROM_SAM_ATTR;
1996                 list_add_tail(&cmd->se_delayed_node,
1997                                 &cmd->se_dev->delayed_cmd_list);
1998                 spin_unlock(&cmd->se_dev->delayed_cmd_lock);
1999
2000                 pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
2001                         " delayed CMD list, se_ordered_id: %u\n",
2002                         cmd->t_task_cdb[0], cmd->sam_task_attr,
2003                         cmd->se_ordered_id);
2004                 /*
2005                  * Return zero to let transport_execute_tasks() know
2006                  * not to add the delayed tasks to the execution list.
2007                  */
2008                 return 0;
2009         }
2010         /*
2011          * Otherwise, no ORDERED task attributes exist..
2012          */
2013         return 1;
2014 }
2015
2016 /*
2017  * Called from fabric module context in transport_generic_new_cmd() and
2018  * transport_generic_process_write()
2019  */
2020 static int transport_execute_tasks(struct se_cmd *cmd)
2021 {
2022         int add_tasks;
2023
2024         if (se_dev_check_online(cmd->se_dev) != 0) {
2025                 cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2026                 transport_generic_request_failure(cmd);
2027                 return 0;
2028         }
2029
2030         /*
2031          * Call transport_cmd_check_stop() to see if a fabric exception
2032          * has occurred that prevents execution.
2033          */
2034         if (!transport_cmd_check_stop(cmd, 0, TRANSPORT_PROCESSING)) {
2035                 /*
2036                  * Check for SAM Task Attribute emulation and HEAD_OF_QUEUE
2037                  * attribute for the tasks of the received struct se_cmd CDB
2038                  */
2039                 add_tasks = transport_execute_task_attr(cmd);
2040                 if (!add_tasks)
2041                         goto execute_tasks;
2042                 /*
2043                  * This calls transport_add_tasks_from_cmd() to handle
2044                  * HEAD_OF_QUEUE ordering for SAM Task Attribute emulation
2045                  * (if enabled) in __transport_add_task_to_execute_queue() and
2046                  * transport_add_task_check_sam_attr().
2047                  */
2048                 transport_add_tasks_from_cmd(cmd);
2049         }
2050         /*
2051          * Kick the execution queue for the cmd associated struct se_device
2052          * storage object.
2053          */
2054 execute_tasks:
2055         __transport_execute_tasks(cmd->se_dev);
2056         return 0;
2057 }
2058
2059 /*
2060  * Called to check struct se_device tcq depth window, and once open pull struct se_task
2061  * from struct se_device->execute_task_list and
2062  *
2063  * Called from transport_processing_thread()
2064  */
2065 static int __transport_execute_tasks(struct se_device *dev)
2066 {
2067         int error;
2068         struct se_cmd *cmd = NULL;
2069         struct se_task *task = NULL;
2070         unsigned long flags;
2071
2072         /*
2073          * Check if there is enough room in the device and HBA queue to send
2074          * struct se_tasks to the selected transport.
2075          */
2076 check_depth:
2077         if (!atomic_read(&dev->depth_left))
2078                 return transport_tcq_window_closed(dev);
2079
2080         dev->dev_tcq_window_closed = 0;
2081
2082         spin_lock_irq(&dev->execute_task_lock);
2083         if (list_empty(&dev->execute_task_list)) {
2084                 spin_unlock_irq(&dev->execute_task_lock);
2085                 return 0;
2086         }
2087         task = list_first_entry(&dev->execute_task_list,
2088                                 struct se_task, t_execute_list);
2089         __transport_remove_task_from_execute_queue(task, dev);
2090         spin_unlock_irq(&dev->execute_task_lock);
2091
2092         atomic_dec(&dev->depth_left);
2093
2094         cmd = task->task_se_cmd;
2095
2096         spin_lock_irqsave(&cmd->t_state_lock, flags);
2097         task->task_flags |= (TF_ACTIVE | TF_SENT);
2098         atomic_inc(&cmd->t_task_cdbs_sent);
2099
2100         if (atomic_read(&cmd->t_task_cdbs_sent) ==
2101             cmd->t_task_list_num)
2102                 atomic_set(&cmd->t_transport_sent, 1);
2103
2104         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2105
2106         if (cmd->execute_task)
2107                 error = cmd->execute_task(task);
2108         else
2109                 error = dev->transport->do_task(task);
2110         if (error != 0) {
2111                 spin_lock_irqsave(&cmd->t_state_lock, flags);
2112                 task->task_flags &= ~TF_ACTIVE;
2113                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2114                 atomic_set(&cmd->t_transport_sent, 0);
2115                 transport_stop_tasks_for_cmd(cmd);
2116                 atomic_inc(&dev->depth_left);
2117                 transport_generic_request_failure(cmd);
2118         }
2119
2120         goto check_depth;
2121
2122         return 0;
2123 }
2124
2125 static inline u32 transport_get_sectors_6(
2126         unsigned char *cdb,
2127         struct se_cmd *cmd,
2128         int *ret)
2129 {
2130         struct se_device *dev = cmd->se_dev;
2131
2132         /*
2133          * Assume TYPE_DISK for non struct se_device objects.
2134          * Use 8-bit sector value.
2135          */
2136         if (!dev)
2137                 goto type_disk;
2138
2139         /*
2140          * Use 24-bit allocation length for TYPE_TAPE.
2141          */
2142         if (dev->transport->get_device_type(dev) == TYPE_TAPE)
2143                 return (u32)(cdb[2] << 16) + (cdb[3] << 8) + cdb[4];
2144
2145         /*
2146          * Everything else assume TYPE_DISK Sector CDB location.
2147          * Use 8-bit sector value.
2148          */
2149 type_disk:
2150         return (u32)cdb[4];
2151 }
2152
2153 static inline u32 transport_get_sectors_10(
2154         unsigned char *cdb,
2155         struct se_cmd *cmd,
2156         int *ret)
2157 {
2158         struct se_device *dev = cmd->se_dev;
2159
2160         /*
2161          * Assume TYPE_DISK for non struct se_device objects.
2162          * Use 16-bit sector value.
2163          */
2164         if (!dev)
2165                 goto type_disk;
2166
2167         /*
2168          * XXX_10 is not defined in SSC, throw an exception
2169          */
2170         if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2171                 *ret = -EINVAL;
2172                 return 0;
2173         }
2174
2175         /*
2176          * Everything else assume TYPE_DISK Sector CDB location.
2177          * Use 16-bit sector value.
2178          */
2179 type_disk:
2180         return (u32)(cdb[7] << 8) + cdb[8];
2181 }
2182
2183 static inline u32 transport_get_sectors_12(
2184         unsigned char *cdb,
2185         struct se_cmd *cmd,
2186         int *ret)
2187 {
2188         struct se_device *dev = cmd->se_dev;
2189
2190         /*
2191          * Assume TYPE_DISK for non struct se_device objects.
2192          * Use 32-bit sector value.
2193          */
2194         if (!dev)
2195                 goto type_disk;
2196
2197         /*
2198          * XXX_12 is not defined in SSC, throw an exception
2199          */
2200         if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2201                 *ret = -EINVAL;
2202                 return 0;
2203         }
2204
2205         /*
2206          * Everything else assume TYPE_DISK Sector CDB location.
2207          * Use 32-bit sector value.
2208          */
2209 type_disk:
2210         return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
2211 }
2212
2213 static inline u32 transport_get_sectors_16(
2214         unsigned char *cdb,
2215         struct se_cmd *cmd,
2216         int *ret)
2217 {
2218         struct se_device *dev = cmd->se_dev;
2219
2220         /*
2221          * Assume TYPE_DISK for non struct se_device objects.
2222          * Use 32-bit sector value.
2223          */
2224         if (!dev)
2225                 goto type_disk;
2226
2227         /*
2228          * Use 24-bit allocation length for TYPE_TAPE.
2229          */
2230         if (dev->transport->get_device_type(dev) == TYPE_TAPE)
2231                 return (u32)(cdb[12] << 16) + (cdb[13] << 8) + cdb[14];
2232
2233 type_disk:
2234         return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
2235                     (cdb[12] << 8) + cdb[13];
2236 }
2237
2238 /*
2239  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
2240  */
2241 static inline u32 transport_get_sectors_32(
2242         unsigned char *cdb,
2243         struct se_cmd *cmd,
2244         int *ret)
2245 {
2246         /*
2247          * Assume TYPE_DISK for non struct se_device objects.
2248          * Use 32-bit sector value.
2249          */
2250         return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
2251                     (cdb[30] << 8) + cdb[31];
2252
2253 }
2254
2255 static inline u32 transport_get_size(
2256         u32 sectors,
2257         unsigned char *cdb,
2258         struct se_cmd *cmd)
2259 {
2260         struct se_device *dev = cmd->se_dev;
2261
2262         if (dev->transport->get_device_type(dev) == TYPE_TAPE) {
2263                 if (cdb[1] & 1) { /* sectors */
2264                         return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
2265                 } else /* bytes */
2266                         return sectors;
2267         }
2268 #if 0
2269         pr_debug("Returning block_size: %u, sectors: %u == %u for"
2270                         " %s object\n", dev->se_sub_dev->se_dev_attrib.block_size, sectors,
2271                         dev->se_sub_dev->se_dev_attrib.block_size * sectors,
2272                         dev->transport->name);
2273 #endif
2274         return dev->se_sub_dev->se_dev_attrib.block_size * sectors;
2275 }
2276
2277 static void transport_xor_callback(struct se_cmd *cmd)
2278 {
2279         unsigned char *buf, *addr;
2280         struct scatterlist *sg;
2281         unsigned int offset;
2282         int i;
2283         int count;
2284         /*
2285          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
2286          *
2287          * 1) read the specified logical block(s);
2288          * 2) transfer logical blocks from the data-out buffer;
2289          * 3) XOR the logical blocks transferred from the data-out buffer with
2290          *    the logical blocks read, storing the resulting XOR data in a buffer;
2291          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
2292          *    blocks transferred from the data-out buffer; and
2293          * 5) transfer the resulting XOR data to the data-in buffer.
2294          */
2295         buf = kmalloc(cmd->data_length, GFP_KERNEL);
2296         if (!buf) {
2297                 pr_err("Unable to allocate xor_callback buf\n");
2298                 return;
2299         }
2300         /*
2301          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
2302          * into the locally allocated *buf
2303          */
2304         sg_copy_to_buffer(cmd->t_data_sg,
2305                           cmd->t_data_nents,
2306                           buf,
2307                           cmd->data_length);
2308
2309         /*
2310          * Now perform the XOR against the BIDI read memory located at
2311          * cmd->t_mem_bidi_list
2312          */
2313
2314         offset = 0;
2315         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
2316                 addr = kmap_atomic(sg_page(sg), KM_USER0);
2317                 if (!addr)
2318                         goto out;
2319
2320                 for (i = 0; i < sg->length; i++)
2321                         *(addr + sg->offset + i) ^= *(buf + offset + i);
2322
2323                 offset += sg->length;
2324                 kunmap_atomic(addr, KM_USER0);
2325         }
2326
2327 out:
2328         kfree(buf);
2329 }
2330
2331 /*
2332  * Used to obtain Sense Data from underlying Linux/SCSI struct scsi_cmnd
2333  */
2334 static int transport_get_sense_data(struct se_cmd *cmd)
2335 {
2336         unsigned char *buffer = cmd->sense_buffer, *sense_buffer = NULL;
2337         struct se_device *dev = cmd->se_dev;
2338         struct se_task *task = NULL, *task_tmp;
2339         unsigned long flags;
2340         u32 offset = 0;
2341
2342         WARN_ON(!cmd->se_lun);
2343
2344         if (!dev)
2345                 return 0;
2346
2347         spin_lock_irqsave(&cmd->t_state_lock, flags);
2348         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2349                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2350                 return 0;
2351         }
2352
2353         list_for_each_entry_safe(task, task_tmp,
2354                                 &cmd->t_task_list, t_list) {
2355                 if (!task->task_sense)
2356                         continue;
2357
2358                 if (!dev->transport->get_sense_buffer) {
2359                         pr_err("dev->transport->get_sense_buffer"
2360                                         " is NULL\n");
2361                         continue;
2362                 }
2363
2364                 sense_buffer = dev->transport->get_sense_buffer(task);
2365                 if (!sense_buffer) {
2366                         pr_err("ITT[0x%08x]_TASK[%p]: Unable to locate"
2367                                 " sense buffer for task with sense\n",
2368                                 cmd->se_tfo->get_task_tag(cmd), task);
2369                         continue;
2370                 }
2371                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2372
2373                 offset = cmd->se_tfo->set_fabric_sense_len(cmd,
2374                                 TRANSPORT_SENSE_BUFFER);
2375
2376                 memcpy(&buffer[offset], sense_buffer,
2377                                 TRANSPORT_SENSE_BUFFER);
2378                 cmd->scsi_status = task->task_scsi_status;
2379                 /* Automatically padded */
2380                 cmd->scsi_sense_length =
2381                                 (TRANSPORT_SENSE_BUFFER + offset);
2382
2383                 pr_debug("HBA_[%u]_PLUG[%s]: Set SAM STATUS: 0x%02x"
2384                                 " and sense\n",
2385                         dev->se_hba->hba_id, dev->transport->name,
2386                                 cmd->scsi_status);
2387                 return 0;
2388         }
2389         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2390
2391         return -1;
2392 }
2393
2394 static inline long long transport_dev_end_lba(struct se_device *dev)
2395 {
2396         return dev->transport->get_blocks(dev) + 1;
2397 }
2398
2399 static int transport_cmd_get_valid_sectors(struct se_cmd *cmd)
2400 {
2401         struct se_device *dev = cmd->se_dev;
2402         u32 sectors;
2403
2404         if (dev->transport->get_device_type(dev) != TYPE_DISK)
2405                 return 0;
2406
2407         sectors = (cmd->data_length / dev->se_sub_dev->se_dev_attrib.block_size);
2408
2409         if ((cmd->t_task_lba + sectors) > transport_dev_end_lba(dev)) {
2410                 pr_err("LBA: %llu Sectors: %u exceeds"
2411                         " transport_dev_end_lba(): %llu\n",
2412                         cmd->t_task_lba, sectors,
2413                         transport_dev_end_lba(dev));
2414                 return -EINVAL;
2415         }
2416
2417         return 0;
2418 }
2419
2420 static int target_check_write_same_discard(unsigned char *flags, struct se_device *dev)
2421 {
2422         /*
2423          * Determine if the received WRITE_SAME is used to for direct
2424          * passthrough into Linux/SCSI with struct request via TCM/pSCSI
2425          * or we are signaling the use of internal WRITE_SAME + UNMAP=1
2426          * emulation for -> Linux/BLOCK disbard with TCM/IBLOCK code.
2427          */
2428         int passthrough = (dev->transport->transport_type ==
2429                                 TRANSPORT_PLUGIN_PHBA_PDEV);
2430
2431         if (!passthrough) {
2432                 if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
2433                         pr_err("WRITE_SAME PBDATA and LBDATA"
2434                                 " bits not supported for Block Discard"
2435                                 " Emulation\n");
2436                         return -ENOSYS;
2437                 }
2438                 /*
2439                  * Currently for the emulated case we only accept
2440                  * tpws with the UNMAP=1 bit set.
2441                  */
2442                 if (!(flags[0] & 0x08)) {
2443                         pr_err("WRITE_SAME w/o UNMAP bit not"
2444                                 " supported for Block Discard Emulation\n");
2445                         return -ENOSYS;
2446                 }
2447         }
2448
2449         return 0;
2450 }
2451
2452 /*      transport_generic_cmd_sequencer():
2453  *
2454  *      Generic Command Sequencer that should work for most DAS transport
2455  *      drivers.
2456  *
2457  *      Called from transport_generic_allocate_tasks() in the $FABRIC_MOD
2458  *      RX Thread.
2459  *
2460  *      FIXME: Need to support other SCSI OPCODES where as well.
2461  */
2462 static int transport_generic_cmd_sequencer(
2463         struct se_cmd *cmd,
2464         unsigned char *cdb)
2465 {
2466         struct se_device *dev = cmd->se_dev;
2467         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
2468         int ret = 0, sector_ret = 0, passthrough;
2469         u32 sectors = 0, size = 0, pr_reg_type = 0;
2470         u16 service_action;
2471         u8 alua_ascq = 0;
2472         /*
2473          * Check for an existing UNIT ATTENTION condition
2474          */
2475         if (core_scsi3_ua_check(cmd, cdb) < 0) {
2476                 cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2477                 cmd->scsi_sense_reason = TCM_CHECK_CONDITION_UNIT_ATTENTION;
2478                 return -EINVAL;
2479         }
2480         /*
2481          * Check status of Asymmetric Logical Unit Assignment port
2482          */
2483         ret = su_dev->t10_alua.alua_state_check(cmd, cdb, &alua_ascq);
2484         if (ret != 0) {
2485                 /*
2486                  * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
2487                  * The ALUA additional sense code qualifier (ASCQ) is determined
2488                  * by the ALUA primary or secondary access state..
2489                  */
2490                 if (ret > 0) {
2491 #if 0
2492                         pr_debug("[%s]: ALUA TG Port not available,"
2493                                 " SenseKey: NOT_READY, ASC/ASCQ: 0x04/0x%02x\n",
2494                                 cmd->se_tfo->get_fabric_name(), alua_ascq);
2495 #endif
2496                         transport_set_sense_codes(cmd, 0x04, alua_ascq);
2497                         cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2498                         cmd->scsi_sense_reason = TCM_CHECK_CONDITION_NOT_READY;
2499                         return -EINVAL;
2500                 }
2501                 goto out_invalid_cdb_field;
2502         }
2503         /*
2504          * Check status for SPC-3 Persistent Reservations
2505          */
2506         if (su_dev->t10_pr.pr_ops.t10_reservation_check(cmd, &pr_reg_type) != 0) {
2507                 if (su_dev->t10_pr.pr_ops.t10_seq_non_holder(
2508                                         cmd, cdb, pr_reg_type) != 0) {
2509                         cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
2510                         cmd->se_cmd_flags |= SCF_SCSI_RESERVATION_CONFLICT;
2511                         cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2512                         return -EBUSY;
2513                 }
2514                 /*
2515                  * This means the CDB is allowed for the SCSI Initiator port
2516                  * when said port is *NOT* holding the legacy SPC-2 or
2517                  * SPC-3 Persistent Reservation.
2518                  */
2519         }
2520
2521         /*
2522          * If we operate in passthrough mode we skip most CDB emulation and
2523          * instead hand the commands down to the physical SCSI device.
2524          */
2525         passthrough =
2526                 (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV);
2527
2528         switch (cdb[0]) {
2529         case READ_6:
2530                 sectors = transport_get_sectors_6(cdb, cmd, &sector_ret);
2531                 if (sector_ret)
2532                         goto out_unsupported_cdb;
2533                 size = transport_get_size(sectors, cdb, cmd);
2534                 cmd->t_task_lba = transport_lba_21(cdb);
2535                 cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2536                 break;
2537         case READ_10:
2538                 sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2539                 if (sector_ret)
2540                         goto out_unsupported_cdb;
2541                 size = transport_get_size(sectors, cdb, cmd);
2542                 cmd->t_task_lba = transport_lba_32(cdb);
2543                 cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2544                 break;
2545         case READ_12:
2546                 sectors = transport_get_sectors_12(cdb, cmd, &sector_ret);
2547                 if (sector_ret)
2548                         goto out_unsupported_cdb;
2549                 size = transport_get_size(sectors, cdb, cmd);
2550                 cmd->t_task_lba = transport_lba_32(cdb);
2551                 cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2552                 break;
2553         case READ_16:
2554                 sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2555                 if (sector_ret)
2556                         goto out_unsupported_cdb;
2557                 size = transport_get_size(sectors, cdb, cmd);
2558                 cmd->t_task_lba = transport_lba_64(cdb);
2559                 cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2560                 break;
2561         case WRITE_6:
2562                 sectors = transport_get_sectors_6(cdb, cmd, &sector_ret);
2563                 if (sector_ret)
2564                         goto out_unsupported_cdb;
2565                 size = transport_get_size(sectors, cdb, cmd);
2566                 cmd->t_task_lba = transport_lba_21(cdb);
2567                 cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2568                 break;
2569         case WRITE_10:
2570                 sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2571                 if (sector_ret)
2572                         goto out_unsupported_cdb;
2573                 size = transport_get_size(sectors, cdb, cmd);
2574                 cmd->t_task_lba = transport_lba_32(cdb);
2575                 if (cdb[1] & 0x8)
2576                         cmd->se_cmd_flags |= SCF_FUA;
2577                 cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2578                 break;
2579         case WRITE_12:
2580                 sectors = transport_get_sectors_12(cdb, cmd, &sector_ret);
2581                 if (sector_ret)
2582                         goto out_unsupported_cdb;
2583                 size = transport_get_size(sectors, cdb, cmd);
2584                 cmd->t_task_lba = transport_lba_32(cdb);
2585                 if (cdb[1] & 0x8)
2586                         cmd->se_cmd_flags |= SCF_FUA;
2587                 cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2588                 break;
2589         case WRITE_16:
2590                 sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2591                 if (sector_ret)
2592                         goto out_unsupported_cdb;
2593                 size = transport_get_size(sectors, cdb, cmd);
2594                 cmd->t_task_lba = transport_lba_64(cdb);
2595                 if (cdb[1] & 0x8)
2596                         cmd->se_cmd_flags |= SCF_FUA;
2597                 cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2598                 break;
2599         case XDWRITEREAD_10:
2600                 if ((cmd->data_direction != DMA_TO_DEVICE) ||
2601                     !(cmd->t_tasks_bidi))
2602                         goto out_invalid_cdb_field;
2603                 sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2604                 if (sector_ret)
2605                         goto out_unsupported_cdb;
2606                 size = transport_get_size(sectors, cdb, cmd);
2607                 cmd->t_task_lba = transport_lba_32(cdb);
2608                 cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2609
2610                 /*
2611                  * Do now allow BIDI commands for passthrough mode.
2612                  */
2613                 if (passthrough)
2614                         goto out_unsupported_cdb;
2615
2616                 /*
2617                  * Setup BIDI XOR callback to be run after I/O completion.
2618                  */
2619                 cmd->transport_complete_callback = &transport_xor_callback;
2620                 if (cdb[1] & 0x8)
2621                         cmd->se_cmd_flags |= SCF_FUA;
2622                 break;
2623         case VARIABLE_LENGTH_CMD:
2624                 service_action = get_unaligned_be16(&cdb[8]);
2625                 switch (service_action) {
2626                 case XDWRITEREAD_32:
2627                         sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
2628                         if (sector_ret)
2629                                 goto out_unsupported_cdb;
2630                         size = transport_get_size(sectors, cdb, cmd);
2631                         /*
2632                          * Use WRITE_32 and READ_32 opcodes for the emulated
2633                          * XDWRITE_READ_32 logic.
2634                          */
2635                         cmd->t_task_lba = transport_lba_64_ext(cdb);
2636                         cmd->se_cmd_flags |= SCF_SCSI_DATA_SG_IO_CDB;
2637
2638                         /*
2639                          * Do now allow BIDI commands for passthrough mode.
2640                          */
2641                         if (passthrough)
2642                                 goto out_unsupported_cdb;
2643
2644                         /*
2645                          * Setup BIDI XOR callback to be run during after I/O
2646                          * completion.
2647                          */
2648                         cmd->transport_complete_callback = &transport_xor_callback;
2649                         if (cdb[1] & 0x8)
2650                                 cmd->se_cmd_flags |= SCF_FUA;
2651                         break;
2652                 case WRITE_SAME_32:
2653                         sectors = transport_get_sectors_32(cdb, cmd, &sector_ret);
2654                         if (sector_ret)
2655                                 goto out_unsupported_cdb;
2656
2657                         if (sectors)
2658                                 size = transport_get_size(1, cdb, cmd);
2659                         else {
2660                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
2661                                        " supported\n");
2662                                 goto out_invalid_cdb_field;
2663                         }
2664
2665                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
2666                         cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2667
2668                         if (target_check_write_same_discard(&cdb[10], dev) < 0)
2669                                 goto out_invalid_cdb_field;
2670                         if (!passthrough)
2671                                 cmd->execute_task = target_emulate_write_same;
2672                         break;
2673                 default:
2674                         pr_err("VARIABLE_LENGTH_CMD service action"
2675                                 " 0x%04x not supported\n", service_action);
2676                         goto out_unsupported_cdb;
2677                 }
2678                 break;
2679         case MAINTENANCE_IN:
2680                 if (dev->transport->get_device_type(dev) != TYPE_ROM) {
2681                         /* MAINTENANCE_IN from SCC-2 */
2682                         /*
2683                          * Check for emulated MI_REPORT_TARGET_PGS.
2684                          */
2685                         if (cdb[1] == MI_REPORT_TARGET_PGS &&
2686                             su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
2687                                 cmd->execute_task =
2688                                         target_emulate_report_target_port_groups;
2689                         }
2690                         size = (cdb[6] << 24) | (cdb[7] << 16) |
2691                                (cdb[8] << 8) | cdb[9];
2692                 } else {
2693                         /* GPCMD_SEND_KEY from multi media commands */
2694                         size = (cdb[8] << 8) + cdb[9];
2695                 }
2696                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2697                 break;
2698         case MODE_SELECT:
2699                 size = cdb[4];
2700                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2701                 break;
2702         case MODE_SELECT_10:
2703                 size = (cdb[7] << 8) + cdb[8];
2704                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2705                 break;
2706         case MODE_SENSE:
2707                 size = cdb[4];
2708                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2709                 if (!passthrough)
2710                         cmd->execute_task = target_emulate_modesense;
2711                 break;
2712         case MODE_SENSE_10:
2713                 size = (cdb[7] << 8) + cdb[8];
2714                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2715                 if (!passthrough)
2716                         cmd->execute_task = target_emulate_modesense;
2717                 break;
2718         case GPCMD_READ_BUFFER_CAPACITY:
2719         case GPCMD_SEND_OPC:
2720         case LOG_SELECT:
2721         case LOG_SENSE:
2722                 size = (cdb[7] << 8) + cdb[8];
2723                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2724                 break;
2725         case READ_BLOCK_LIMITS:
2726                 size = READ_BLOCK_LEN;
2727                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2728                 break;
2729         case GPCMD_GET_CONFIGURATION:
2730         case GPCMD_READ_FORMAT_CAPACITIES:
2731         case GPCMD_READ_DISC_INFO:
2732         case GPCMD_READ_TRACK_RZONE_INFO:
2733                 size = (cdb[7] << 8) + cdb[8];
2734                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2735                 break;
2736         case PERSISTENT_RESERVE_IN:
2737                 if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
2738                         cmd->execute_task = target_scsi3_emulate_pr_in;
2739                 size = (cdb[7] << 8) + cdb[8];
2740                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2741                 break;
2742         case PERSISTENT_RESERVE_OUT:
2743                 if (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS)
2744                         cmd->execute_task = target_scsi3_emulate_pr_out;
2745                 size = (cdb[7] << 8) + cdb[8];
2746                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2747                 break;
2748         case GPCMD_MECHANISM_STATUS:
2749         case GPCMD_READ_DVD_STRUCTURE:
2750                 size = (cdb[8] << 8) + cdb[9];
2751                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2752                 break;
2753         case READ_POSITION:
2754                 size = READ_POSITION_LEN;
2755                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2756                 break;
2757         case MAINTENANCE_OUT:
2758                 if (dev->transport->get_device_type(dev) != TYPE_ROM) {
2759                         /* MAINTENANCE_OUT from SCC-2
2760                          *
2761                          * Check for emulated MO_SET_TARGET_PGS.
2762                          */
2763                         if (cdb[1] == MO_SET_TARGET_PGS &&
2764                             su_dev->t10_alua.alua_type == SPC3_ALUA_EMULATED) {
2765                                 cmd->execute_task =
2766                                         target_emulate_set_target_port_groups;
2767                         }
2768
2769                         size = (cdb[6] << 24) | (cdb[7] << 16) |
2770                                (cdb[8] << 8) | cdb[9];
2771                 } else  {
2772                         /* GPCMD_REPORT_KEY from multi media commands */
2773                         size = (cdb[8] << 8) + cdb[9];
2774                 }
2775                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2776                 break;
2777         case INQUIRY:
2778                 size = (cdb[3] << 8) + cdb[4];
2779                 /*
2780                  * Do implict HEAD_OF_QUEUE processing for INQUIRY.
2781                  * See spc4r17 section 5.3
2782                  */
2783                 if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
2784                         cmd->sam_task_attr = MSG_HEAD_TAG;
2785                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2786                 if (!passthrough)
2787                         cmd->execute_task = target_emulate_inquiry;
2788                 break;
2789         case READ_BUFFER:
2790                 size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
2791                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2792                 break;
2793         case READ_CAPACITY:
2794                 size = READ_CAP_LEN;
2795                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2796                 if (!passthrough)
2797                         cmd->execute_task = target_emulate_readcapacity;
2798                 break;
2799         case READ_MEDIA_SERIAL_NUMBER:
2800         case SECURITY_PROTOCOL_IN:
2801         case SECURITY_PROTOCOL_OUT:
2802                 size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
2803                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2804                 break;
2805         case SERVICE_ACTION_IN:
2806                 switch (cmd->t_task_cdb[1] & 0x1f) {
2807                 case SAI_READ_CAPACITY_16:
2808                         if (!passthrough)
2809                                 cmd->execute_task =
2810                                         target_emulate_readcapacity_16;
2811                         break;
2812                 default:
2813                         if (passthrough)
2814                                 break;
2815
2816                         pr_err("Unsupported SA: 0x%02x\n",
2817                                 cmd->t_task_cdb[1] & 0x1f);
2818                         goto out_unsupported_cdb;
2819                 }
2820                 /*FALLTHROUGH*/
2821         case ACCESS_CONTROL_IN:
2822         case ACCESS_CONTROL_OUT:
2823         case EXTENDED_COPY:
2824         case READ_ATTRIBUTE:
2825         case RECEIVE_COPY_RESULTS:
2826         case WRITE_ATTRIBUTE:
2827                 size = (cdb[10] << 24) | (cdb[11] << 16) |
2828                        (cdb[12] << 8) | cdb[13];
2829                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2830                 break;
2831         case RECEIVE_DIAGNOSTIC:
2832         case SEND_DIAGNOSTIC:
2833                 size = (cdb[3] << 8) | cdb[4];
2834                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2835                 break;
2836 /* #warning FIXME: Figure out correct GPCMD_READ_CD blocksize. */
2837 #if 0
2838         case GPCMD_READ_CD:
2839                 sectors = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
2840                 size = (2336 * sectors);
2841                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2842                 break;
2843 #endif
2844         case READ_TOC:
2845                 size = cdb[8];
2846                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2847                 break;
2848         case REQUEST_SENSE:
2849                 size = cdb[4];
2850                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2851                 if (!passthrough)
2852                         cmd->execute_task = target_emulate_request_sense;
2853                 break;
2854         case READ_ELEMENT_STATUS:
2855                 size = 65536 * cdb[7] + 256 * cdb[8] + cdb[9];
2856                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2857                 break;
2858         case WRITE_BUFFER:
2859                 size = (cdb[6] << 16) + (cdb[7] << 8) + cdb[8];
2860                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2861                 break;
2862         case RESERVE:
2863         case RESERVE_10:
2864                 /*
2865                  * The SPC-2 RESERVE does not contain a size in the SCSI CDB.
2866                  * Assume the passthrough or $FABRIC_MOD will tell us about it.
2867                  */
2868                 if (cdb[0] == RESERVE_10)
2869                         size = (cdb[7] << 8) | cdb[8];
2870                 else
2871                         size = cmd->data_length;
2872
2873                 /*
2874                  * Setup the legacy emulated handler for SPC-2 and
2875                  * >= SPC-3 compatible reservation handling (CRH=1)
2876                  * Otherwise, we assume the underlying SCSI logic is
2877                  * is running in SPC_PASSTHROUGH, and wants reservations
2878                  * emulation disabled.
2879                  */
2880                 if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
2881                         cmd->execute_task = target_scsi2_reservation_reserve;
2882                 cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
2883                 break;
2884         case RELEASE:
2885         case RELEASE_10:
2886                 /*
2887                  * The SPC-2 RELEASE does not contain a size in the SCSI CDB.
2888                  * Assume the passthrough or $FABRIC_MOD will tell us about it.
2889                 */
2890                 if (cdb[0] == RELEASE_10)
2891                         size = (cdb[7] << 8) | cdb[8];
2892                 else
2893                         size = cmd->data_length;
2894
2895                 if (su_dev->t10_pr.res_type != SPC_PASSTHROUGH)
2896                         cmd->execute_task = target_scsi2_reservation_release;
2897                 cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
2898                 break;
2899         case SYNCHRONIZE_CACHE:
2900         case 0x91: /* SYNCHRONIZE_CACHE_16: */
2901                 /*
2902                  * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
2903                  */
2904                 if (cdb[0] == SYNCHRONIZE_CACHE) {
2905                         sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2906                         cmd->t_task_lba = transport_lba_32(cdb);
2907                 } else {
2908                         sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2909                         cmd->t_task_lba = transport_lba_64(cdb);
2910                 }
2911                 if (sector_ret)
2912                         goto out_unsupported_cdb;
2913
2914                 size = transport_get_size(sectors, cdb, cmd);
2915                 cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
2916
2917                 if (passthrough)
2918                         break;
2919
2920                 /*
2921                  * Check to ensure that LBA + Range does not exceed past end of
2922                  * device for IBLOCK and FILEIO ->do_sync_cache() backend calls
2923                  */
2924                 if ((cmd->t_task_lba != 0) || (sectors != 0)) {
2925                         if (transport_cmd_get_valid_sectors(cmd) < 0)
2926                                 goto out_invalid_cdb_field;
2927                 }
2928                 cmd->execute_task = target_emulate_synchronize_cache;
2929                 break;
2930         case UNMAP:
2931                 size = get_unaligned_be16(&cdb[7]);
2932                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2933                 if (!passthrough)
2934                         cmd->execute_task = target_emulate_unmap;
2935                 break;
2936         case WRITE_SAME_16:
2937                 sectors = transport_get_sectors_16(cdb, cmd, &sector_ret);
2938                 if (sector_ret)
2939                         goto out_unsupported_cdb;
2940
2941                 if (sectors)
2942                         size = transport_get_size(1, cdb, cmd);
2943                 else {
2944                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
2945                         goto out_invalid_cdb_field;
2946                 }
2947
2948                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
2949                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2950
2951                 if (target_check_write_same_discard(&cdb[1], dev) < 0)
2952                         goto out_invalid_cdb_field;
2953                 if (!passthrough)
2954                         cmd->execute_task = target_emulate_write_same;
2955                 break;
2956         case WRITE_SAME:
2957                 sectors = transport_get_sectors_10(cdb, cmd, &sector_ret);
2958                 if (sector_ret)
2959                         goto out_unsupported_cdb;
2960
2961                 if (sectors)
2962                         size = transport_get_size(1, cdb, cmd);
2963                 else {
2964                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
2965                         goto out_invalid_cdb_field;
2966                 }
2967
2968                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
2969                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
2970                 /*
2971                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
2972                  * of byte 1 bit 3 UNMAP instead of original reserved field
2973                  */
2974                 if (target_check_write_same_discard(&cdb[1], dev) < 0)
2975                         goto out_invalid_cdb_field;
2976                 if (!passthrough)
2977                         cmd->execute_task = target_emulate_write_same;
2978                 break;
2979         case ALLOW_MEDIUM_REMOVAL:
2980         case ERASE:
2981         case REZERO_UNIT:
2982         case SEEK_10:
2983         case SPACE:
2984         case START_STOP:
2985         case TEST_UNIT_READY:
2986         case VERIFY:
2987         case WRITE_FILEMARKS:
2988                 cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
2989                 if (!passthrough)
2990                         cmd->execute_task = target_emulate_noop;
2991                 break;
2992         case GPCMD_CLOSE_TRACK:
2993         case INITIALIZE_ELEMENT_STATUS:
2994         case GPCMD_LOAD_UNLOAD:
2995         case GPCMD_SET_SPEED:
2996         case MOVE_MEDIUM:
2997                 cmd->se_cmd_flags |= SCF_SCSI_NON_DATA_CDB;
2998                 break;
2999         case REPORT_LUNS:
3000                 cmd->execute_task = target_report_luns;
3001                 size = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
3002                 /*
3003                  * Do implict HEAD_OF_QUEUE processing for REPORT_LUNS
3004                  * See spc4r17 section 5.3
3005                  */
3006                 if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3007                         cmd->sam_task_attr = MSG_HEAD_TAG;
3008                 cmd->se_cmd_flags |= SCF_SCSI_CONTROL_SG_IO_CDB;
3009                 break;
3010         default:
3011                 pr_warn("TARGET_CORE[%s]: Unsupported SCSI Opcode"
3012                         " 0x%02x, sending CHECK_CONDITION.\n",
3013                         cmd->se_tfo->get_fabric_name(), cdb[0]);
3014                 goto out_unsupported_cdb;
3015         }
3016
3017         if (size != cmd->data_length) {
3018                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
3019                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
3020                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
3021                                 cmd->data_length, size, cdb[0]);
3022
3023                 cmd->cmd_spdtl = size;
3024
3025                 if (cmd->data_direction == DMA_TO_DEVICE) {
3026                         pr_err("Rejecting underflow/overflow"
3027                                         " WRITE data\n");
3028                         goto out_invalid_cdb_field;
3029                 }
3030                 /*
3031                  * Reject READ_* or WRITE_* with overflow/underflow for
3032                  * type SCF_SCSI_DATA_SG_IO_CDB.
3033                  */
3034                 if (!ret && (dev->se_sub_dev->se_dev_attrib.block_size != 512))  {
3035                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
3036                                 " CDB on non 512-byte sector setup subsystem"
3037                                 " plugin: %s\n", dev->transport->name);
3038                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
3039                         goto out_invalid_cdb_field;
3040                 }
3041
3042                 if (size > cmd->data_length) {
3043                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
3044                         cmd->residual_count = (size - cmd->data_length);
3045                 } else {
3046                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
3047                         cmd->residual_count = (cmd->data_length - size);
3048                 }
3049                 cmd->data_length = size;
3050         }
3051
3052         /* reject any command that we don't have a handler for */
3053         if (!(passthrough || cmd->execute_task ||
3054              (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB)))
3055                 goto out_unsupported_cdb;
3056
3057         /* Let's limit control cdbs to a page, for simplicity's sake. */
3058         if ((cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB) &&
3059             size > PAGE_SIZE)
3060                 goto out_invalid_cdb_field;
3061
3062         transport_set_supported_SAM_opcode(cmd);
3063         return ret;
3064
3065 out_unsupported_cdb:
3066         cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3067         cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
3068         return -EINVAL;
3069 out_invalid_cdb_field:
3070         cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3071         cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3072         return -EINVAL;
3073 }
3074
3075 /*
3076  * Called from I/O completion to determine which dormant/delayed
3077  * and ordered cmds need to have their tasks added to the execution queue.
3078  */
3079 static void transport_complete_task_attr(struct se_cmd *cmd)
3080 {
3081         struct se_device *dev = cmd->se_dev;
3082         struct se_cmd *cmd_p, *cmd_tmp;
3083         int new_active_tasks = 0;
3084
3085         if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
3086                 atomic_dec(&dev->simple_cmds);
3087                 smp_mb__after_atomic_dec();
3088                 dev->dev_cur_ordered_id++;
3089                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
3090                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
3091                         cmd->se_ordered_id);
3092         } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
3093                 atomic_dec(&dev->dev_hoq_count);
3094                 smp_mb__after_atomic_dec();
3095                 dev->dev_cur_ordered_id++;
3096                 pr_debug("Incremented dev_cur_ordered_id: %u for"
3097                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
3098                         cmd->se_ordered_id);
3099         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
3100                 atomic_dec(&dev->dev_ordered_sync);
3101                 smp_mb__after_atomic_dec();
3102
3103                 dev->dev_cur_ordered_id++;
3104                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
3105                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
3106         }
3107         /*
3108          * Process all commands up to the last received
3109          * ORDERED task attribute which requires another blocking
3110          * boundary
3111          */
3112         spin_lock(&dev->delayed_cmd_lock);
3113         list_for_each_entry_safe(cmd_p, cmd_tmp,
3114                         &dev->delayed_cmd_list, se_delayed_node) {
3115
3116                 list_del(&cmd_p->se_delayed_node);
3117                 spin_unlock(&dev->delayed_cmd_lock);
3118
3119                 pr_debug("Calling add_tasks() for"
3120                         " cmd_p: 0x%02x Task Attr: 0x%02x"
3121                         " Dormant -> Active, se_ordered_id: %u\n",
3122                         cmd_p->t_task_cdb[0],
3123                         cmd_p->sam_task_attr, cmd_p->se_ordered_id);
3124
3125                 transport_add_tasks_from_cmd(cmd_p);
3126                 new_active_tasks++;
3127
3128                 spin_lock(&dev->delayed_cmd_lock);
3129                 if (cmd_p->sam_task_attr == MSG_ORDERED_TAG)
3130                         break;
3131         }
3132         spin_unlock(&dev->delayed_cmd_lock);
3133         /*
3134          * If new tasks have become active, wake up the transport thread
3135          * to do the processing of the Active tasks.
3136          */
3137         if (new_active_tasks != 0)
3138                 wake_up_interruptible(&dev->dev_queue_obj.thread_wq);
3139 }
3140
3141 static void transport_complete_qf(struct se_cmd *cmd)
3142 {
3143         int ret = 0;
3144
3145         if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3146                 transport_complete_task_attr(cmd);
3147
3148         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
3149                 ret = cmd->se_tfo->queue_status(cmd);
3150                 if (ret)
3151                         goto out;
3152         }
3153
3154         switch (cmd->data_direction) {
3155         case DMA_FROM_DEVICE:
3156                 ret = cmd->se_tfo->queue_data_in(cmd);
3157                 break;
3158         case DMA_TO_DEVICE:
3159                 if (cmd->t_bidi_data_sg) {
3160                         ret = cmd->se_tfo->queue_data_in(cmd);
3161                         if (ret < 0)
3162                                 break;
3163                 }
3164                 /* Fall through for DMA_TO_DEVICE */
3165         case DMA_NONE:
3166                 ret = cmd->se_tfo->queue_status(cmd);
3167                 break;
3168         default:
3169                 break;
3170         }
3171
3172 out:
3173         if (ret < 0) {
3174                 transport_handle_queue_full(cmd, cmd->se_dev);
3175                 return;
3176         }
3177         transport_lun_remove_cmd(cmd);
3178         transport_cmd_check_stop_to_fabric(cmd);
3179 }
3180
3181 static void transport_handle_queue_full(
3182         struct se_cmd *cmd,
3183         struct se_device *dev)
3184 {
3185         spin_lock_irq(&dev->qf_cmd_lock);
3186         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
3187         atomic_inc(&dev->dev_qf_count);
3188         smp_mb__after_atomic_inc();
3189         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
3190
3191         schedule_work(&cmd->se_dev->qf_work_queue);
3192 }
3193
3194 static void target_complete_ok_work(struct work_struct *work)
3195 {
3196         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3197         int reason = 0, ret;
3198
3199         /*
3200          * Check if we need to move delayed/dormant tasks from cmds on the
3201          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
3202          * Attribute.
3203          */
3204         if (cmd->se_dev->dev_task_attr_type == SAM_TASK_ATTR_EMULATED)
3205                 transport_complete_task_attr(cmd);
3206         /*
3207          * Check to schedule QUEUE_FULL work, or execute an existing
3208          * cmd->transport_qf_callback()
3209          */
3210         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
3211                 schedule_work(&cmd->se_dev->qf_work_queue);
3212
3213         /*
3214          * Check if we need to retrieve a sense buffer from
3215          * the struct se_cmd in question.
3216          */
3217         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
3218                 if (transport_get_sense_data(cmd) < 0)
3219                         reason = TCM_NON_EXISTENT_LUN;
3220
3221                 /*
3222                  * Only set when an struct se_task->task_scsi_status returned
3223                  * a non GOOD status.
3224                  */
3225                 if (cmd->scsi_status) {
3226                         ret = transport_send_check_condition_and_sense(
3227                                         cmd, reason, 1);
3228                         if (ret == -EAGAIN || ret == -ENOMEM)
3229                                 goto queue_full;
3230
3231                         transport_lun_remove_cmd(cmd);
3232                         transport_cmd_check_stop_to_fabric(cmd);
3233                         return;
3234                 }
3235         }
3236         /*
3237          * Check for a callback, used by amongst other things
3238          * XDWRITE_READ_10 emulation.
3239          */
3240         if (cmd->transport_complete_callback)
3241                 cmd->transport_complete_callback(cmd);
3242
3243         switch (cmd->data_direction) {
3244         case DMA_FROM_DEVICE:
3245                 spin_lock(&cmd->se_lun->lun_sep_lock);
3246                 if (cmd->se_lun->lun_sep) {
3247                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
3248                                         cmd->data_length;
3249                 }
3250                 spin_unlock(&cmd->se_lun->lun_sep_lock);
3251
3252                 ret = cmd->se_tfo->queue_data_in(cmd);
3253                 if (ret == -EAGAIN || ret == -ENOMEM)
3254                         goto queue_full;
3255                 break;
3256         case DMA_TO_DEVICE:
3257                 spin_lock(&cmd->se_lun->lun_sep_lock);
3258                 if (cmd->se_lun->lun_sep) {
3259                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
3260                                 cmd->data_length;
3261                 }
3262                 spin_unlock(&cmd->se_lun->lun_sep_lock);
3263                 /*
3264                  * Check if we need to send READ payload for BIDI-COMMAND
3265                  */
3266                 if (cmd->t_bidi_data_sg) {
3267                         spin_lock(&cmd->se_lun->lun_sep_lock);
3268                         if (cmd->se_lun->lun_sep) {
3269                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
3270                                         cmd->data_length;
3271                         }
3272                         spin_unlock(&cmd->se_lun->lun_sep_lock);
3273                         ret = cmd->se_tfo->queue_data_in(cmd);
3274                         if (ret == -EAGAIN || ret == -ENOMEM)
3275                                 goto queue_full;
3276                         break;
3277                 }
3278                 /* Fall through for DMA_TO_DEVICE */
3279         case DMA_NONE:
3280                 ret = cmd->se_tfo->queue_status(cmd);
3281                 if (ret == -EAGAIN || ret == -ENOMEM)
3282                         goto queue_full;
3283                 break;
3284         default:
3285                 break;
3286         }
3287
3288         transport_lun_remove_cmd(cmd);
3289         transport_cmd_check_stop_to_fabric(cmd);
3290         return;
3291
3292 queue_full:
3293         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
3294                 " data_direction: %d\n", cmd, cmd->data_direction);
3295         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
3296         transport_handle_queue_full(cmd, cmd->se_dev);
3297 }
3298
3299 static void transport_free_dev_tasks(struct se_cmd *cmd)
3300 {
3301         struct se_task *task, *task_tmp;
3302         unsigned long flags;
3303         LIST_HEAD(dispose_list);
3304
3305         spin_lock_irqsave(&cmd->t_state_lock, flags);
3306         list_for_each_entry_safe(task, task_tmp,
3307                                 &cmd->t_task_list, t_list) {
3308                 if (!(task->task_flags & TF_ACTIVE))
3309                         list_move_tail(&task->t_list, &dispose_list);
3310         }
3311         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3312
3313         while (!list_empty(&dispose_list)) {
3314                 task = list_first_entry(&dispose_list, struct se_task, t_list);
3315
3316                 if (task->task_sg != cmd->t_data_sg &&
3317                     task->task_sg != cmd->t_bidi_data_sg)
3318                         kfree(task->task_sg);
3319
3320                 list_del(&task->t_list);
3321
3322                 cmd->se_dev->transport->free_task(task);
3323         }
3324 }
3325
3326 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
3327 {
3328         struct scatterlist *sg;
3329         int count;
3330
3331         for_each_sg(sgl, sg, nents, count)
3332                 __free_page(sg_page(sg));
3333
3334         kfree(sgl);
3335 }
3336
3337 static inline void transport_free_pages(struct se_cmd *cmd)
3338 {
3339         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
3340                 return;
3341
3342         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
3343         cmd->t_data_sg = NULL;
3344         cmd->t_data_nents = 0;
3345
3346         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
3347         cmd->t_bidi_data_sg = NULL;
3348         cmd->t_bidi_data_nents = 0;
3349 }
3350
3351 /**
3352  * transport_put_cmd - release a reference to a command
3353  * @cmd:       command to release
3354  *
3355  * This routine releases our reference to the command and frees it if possible.
3356  */
3357 static void transport_put_cmd(struct se_cmd *cmd)
3358 {
3359         unsigned long flags;
3360         int free_tasks = 0;
3361
3362         spin_lock_irqsave(&cmd->t_state_lock, flags);
3363         if (atomic_read(&cmd->t_fe_count)) {
3364                 if (!atomic_dec_and_test(&cmd->t_fe_count))
3365                         goto out_busy;
3366         }
3367
3368         if (atomic_read(&cmd->t_se_count)) {
3369                 if (!atomic_dec_and_test(&cmd->t_se_count))
3370                         goto out_busy;
3371         }
3372
3373         if (atomic_read(&cmd->transport_dev_active)) {
3374                 atomic_set(&cmd->transport_dev_active, 0);
3375                 transport_all_task_dev_remove_state(cmd);
3376                 free_tasks = 1;
3377         }
3378         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3379
3380         if (free_tasks != 0)
3381                 transport_free_dev_tasks(cmd);
3382
3383         transport_free_pages(cmd);
3384         transport_release_cmd(cmd);
3385         return;
3386 out_busy:
3387         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3388 }
3389
3390 /*
3391  * transport_generic_map_mem_to_cmd - Use fabric-alloced pages instead of
3392  * allocating in the core.
3393  * @cmd:  Associated se_cmd descriptor
3394  * @mem:  SGL style memory for TCM WRITE / READ
3395  * @sg_mem_num: Number of SGL elements
3396  * @mem_bidi_in: SGL style memory for TCM BIDI READ
3397  * @sg_mem_bidi_num: Number of BIDI READ SGL elements
3398  *
3399  * Return: nonzero return cmd was rejected for -ENOMEM or inproper usage
3400  * of parameters.
3401  */
3402 int transport_generic_map_mem_to_cmd(
3403         struct se_cmd *cmd,
3404         struct scatterlist *sgl,
3405         u32 sgl_count,
3406         struct scatterlist *sgl_bidi,
3407         u32 sgl_bidi_count)
3408 {
3409         if (!sgl || !sgl_count)
3410                 return 0;
3411
3412         if ((cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) ||
3413             (cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB)) {
3414
3415                 cmd->t_data_sg = sgl;
3416                 cmd->t_data_nents = sgl_count;
3417
3418                 if (sgl_bidi && sgl_bidi_count) {
3419                         cmd->t_bidi_data_sg = sgl_bidi;
3420                         cmd->t_bidi_data_nents = sgl_bidi_count;
3421                 }
3422                 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
3423         }
3424
3425         return 0;
3426 }
3427 EXPORT_SYMBOL(transport_generic_map_mem_to_cmd);
3428
3429 void *transport_kmap_first_data_page(struct se_cmd *cmd)
3430 {
3431         struct scatterlist *sg = cmd->t_data_sg;
3432
3433         BUG_ON(!sg);
3434         /*
3435          * We need to take into account a possible offset here for fabrics like
3436          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
3437          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
3438          */
3439         return kmap(sg_page(sg)) + sg->offset;
3440 }
3441 EXPORT_SYMBOL(transport_kmap_first_data_page);
3442
3443 void transport_kunmap_first_data_page(struct se_cmd *cmd)
3444 {
3445         kunmap(sg_page(cmd->t_data_sg));
3446 }
3447 EXPORT_SYMBOL(transport_kunmap_first_data_page);
3448
3449 static int
3450 transport_generic_get_mem(struct se_cmd *cmd)
3451 {
3452         u32 length = cmd->data_length;
3453         unsigned int nents;
3454         struct page *page;
3455         int i = 0;
3456
3457         nents = DIV_ROUND_UP(length, PAGE_SIZE);
3458         cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
3459         if (!cmd->t_data_sg)
3460                 return -ENOMEM;
3461
3462         cmd->t_data_nents = nents;
3463         sg_init_table(cmd->t_data_sg, nents);
3464
3465         while (length) {
3466                 u32 page_len = min_t(u32, length, PAGE_SIZE);
3467                 page = alloc_page(GFP_KERNEL | __GFP_ZERO);
3468                 if (!page)
3469                         goto out;
3470
3471                 sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
3472                 length -= page_len;
3473                 i++;
3474         }
3475         return 0;
3476
3477 out:
3478         while (i >= 0) {
3479                 __free_page(sg_page(&cmd->t_data_sg[i]));
3480                 i--;
3481         }
3482         kfree(cmd->t_data_sg);
3483         cmd->t_data_sg = NULL;
3484         return -ENOMEM;
3485 }
3486
3487 /* Reduce sectors if they are too long for the device */
3488 static inline sector_t transport_limit_task_sectors(
3489         struct se_device *dev,
3490         unsigned long long lba,
3491         sector_t sectors)
3492 {
3493         sectors = min_t(sector_t, sectors, dev->se_sub_dev->se_dev_attrib.max_sectors);
3494
3495         if (dev->transport->get_device_type(dev) == TYPE_DISK)
3496                 if ((lba + sectors) > transport_dev_end_lba(dev))
3497                         sectors = ((transport_dev_end_lba(dev) - lba) + 1);
3498
3499         return sectors;
3500 }
3501
3502
3503 /*
3504  * This function can be used by HW target mode drivers to create a linked
3505  * scatterlist from all contiguously allocated struct se_task->task_sg[].
3506  * This is intended to be called during the completion path by TCM Core
3507  * when struct target_core_fabric_ops->check_task_sg_chaining is enabled.
3508  */
3509 void transport_do_task_sg_chain(struct se_cmd *cmd)
3510 {
3511         struct scatterlist *sg_first = NULL;
3512         struct scatterlist *sg_prev = NULL;
3513         int sg_prev_nents = 0;
3514         struct scatterlist *sg;
3515         struct se_task *task;
3516         u32 chained_nents = 0;
3517         int i;
3518
3519         BUG_ON(!cmd->se_tfo->task_sg_chaining);
3520
3521         /*
3522          * Walk the struct se_task list and setup scatterlist chains
3523          * for each contiguously allocated struct se_task->task_sg[].
3524          */
3525         list_for_each_entry(task, &cmd->t_task_list, t_list) {
3526                 if (!task->task_sg)
3527                         continue;
3528
3529                 if (!sg_first) {
3530                         sg_first = task->task_sg;
3531                         chained_nents = task->task_sg_nents;
3532                 } else {
3533                         sg_chain(sg_prev, sg_prev_nents, task->task_sg);
3534                         chained_nents += task->task_sg_nents;
3535                 }
3536                 /*
3537                  * For the padded tasks, use the extra SGL vector allocated
3538                  * in transport_allocate_data_tasks() for the sg_prev_nents
3539                  * offset into sg_chain() above.
3540                  *
3541                  * We do not need the padding for the last task (or a single
3542                  * task), but in that case we will never use the sg_prev_nents
3543                  * value below which would be incorrect.
3544                  */
3545                 sg_prev_nents = (task->task_sg_nents + 1);
3546                 sg_prev = task->task_sg;
3547         }
3548         /*
3549          * Setup the starting pointer and total t_tasks_sg_linked_no including
3550          * padding SGs for linking and to mark the end.
3551          */
3552         cmd->t_tasks_sg_chained = sg_first;
3553         cmd->t_tasks_sg_chained_no = chained_nents;
3554
3555         pr_debug("Setup cmd: %p cmd->t_tasks_sg_chained: %p and"
3556                 " t_tasks_sg_chained_no: %u\n", cmd, cmd->t_tasks_sg_chained,
3557                 cmd->t_tasks_sg_chained_no);
3558
3559         for_each_sg(cmd->t_tasks_sg_chained, sg,
3560                         cmd->t_tasks_sg_chained_no, i) {
3561
3562                 pr_debug("SG[%d]: %p page: %p length: %d offset: %d\n",
3563                         i, sg, sg_page(sg), sg->length, sg->offset);
3564                 if (sg_is_chain(sg))
3565                         pr_debug("SG: %p sg_is_chain=1\n", sg);
3566                 if (sg_is_last(sg))
3567                         pr_debug("SG: %p sg_is_last=1\n", sg);
3568         }
3569 }
3570 EXPORT_SYMBOL(transport_do_task_sg_chain);
3571
3572 /*
3573  * Break up cmd into chunks transport can handle
3574  */
3575 static int
3576 transport_allocate_data_tasks(struct se_cmd *cmd,
3577         enum dma_data_direction data_direction,
3578         struct scatterlist *cmd_sg, unsigned int sgl_nents)
3579 {
3580         struct se_device *dev = cmd->se_dev;
3581         int task_count, i;
3582         unsigned long long lba;
3583         sector_t sectors, dev_max_sectors;
3584         u32 sector_size;
3585
3586         if (transport_cmd_get_valid_sectors(cmd) < 0)
3587                 return -EINVAL;
3588
3589         dev_max_sectors = dev->se_sub_dev->se_dev_attrib.max_sectors;
3590         sector_size = dev->se_sub_dev->se_dev_attrib.block_size;
3591
3592         WARN_ON(cmd->data_length % sector_size);
3593
3594         lba = cmd->t_task_lba;
3595         sectors = DIV_ROUND_UP(cmd->data_length, sector_size);
3596         task_count = DIV_ROUND_UP_SECTOR_T(sectors, dev_max_sectors);
3597
3598         /*
3599          * If we need just a single task reuse the SG list in the command
3600          * and avoid a lot of work.
3601          */
3602         if (task_count == 1) {
3603                 struct se_task *task;
3604                 unsigned long flags;
3605
3606                 task = transport_generic_get_task(cmd, data_direction);
3607                 if (!task)
3608                         return -ENOMEM;
3609
3610                 task->task_sg = cmd_sg;
3611                 task->task_sg_nents = sgl_nents;
3612
3613                 task->task_lba = lba;
3614                 task->task_sectors = sectors;
3615                 task->task_size = task->task_sectors * sector_size;
3616
3617                 spin_lock_irqsave(&cmd->t_state_lock, flags);
3618                 list_add_tail(&task->t_list, &cmd->t_task_list);
3619                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3620
3621                 return task_count;
3622         }
3623
3624         for (i = 0; i < task_count; i++) {
3625                 struct se_task *task;
3626                 unsigned int task_size, task_sg_nents_padded;
3627                 struct scatterlist *sg;
3628                 unsigned long flags;
3629                 int count;
3630
3631                 task = transport_generic_get_task(cmd, data_direction);
3632                 if (!task)
3633                         return -ENOMEM;
3634
3635                 task->task_lba = lba;
3636                 task->task_sectors = min(sectors, dev_max_sectors);
3637                 task->task_size = task->task_sectors * sector_size;
3638
3639                 /*
3640                  * This now assumes that passed sg_ents are in PAGE_SIZE chunks
3641                  * in order to calculate the number per task SGL entries
3642                  */
3643                 task->task_sg_nents = DIV_ROUND_UP(task->task_size, PAGE_SIZE);
3644                 /*
3645                  * Check if the fabric module driver is requesting that all
3646                  * struct se_task->task_sg[] be chained together..  If so,
3647                  * then allocate an extra padding SG entry for linking and
3648                  * marking the end of the chained SGL for every task except
3649                  * the last one for (task_count > 1) operation, or skipping
3650                  * the extra padding for the (task_count == 1) case.
3651                  */
3652                 if (cmd->se_tfo->task_sg_chaining && (i < (task_count - 1))) {
3653                         task_sg_nents_padded = (task->task_sg_nents + 1);
3654                 } else
3655                         task_sg_nents_padded = task->task_sg_nents;
3656
3657                 task->task_sg = kmalloc(sizeof(struct scatterlist) *
3658                                         task_sg_nents_padded, GFP_KERNEL);
3659                 if (!task->task_sg) {
3660                         cmd->se_dev->transport->free_task(task);
3661                         return -ENOMEM;
3662                 }
3663
3664                 sg_init_table(task->task_sg, task_sg_nents_padded);
3665
3666                 task_size = task->task_size;
3667
3668                 /* Build new sgl, only up to task_size */
3669                 for_each_sg(task->task_sg, sg, task->task_sg_nents, count) {
3670                         if (cmd_sg->length > task_size)
3671                                 break;
3672
3673                         *sg = *cmd_sg;
3674                         task_size -= cmd_sg->length;
3675                         cmd_sg = sg_next(cmd_sg);
3676                 }
3677
3678                 lba += task->task_sectors;
3679                 sectors -= task->task_sectors;
3680
3681                 spin_lock_irqsave(&cmd->t_state_lock, flags);
3682                 list_add_tail(&task->t_list, &cmd->t_task_list);
3683                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3684         }
3685
3686         return task_count;
3687 }
3688
3689 static int
3690 transport_allocate_control_task(struct se_cmd *cmd)
3691 {
3692         struct se_task *task;
3693         unsigned long flags;
3694
3695         task = transport_generic_get_task(cmd, cmd->data_direction);
3696         if (!task)
3697                 return -ENOMEM;
3698
3699         task->task_sg = cmd->t_data_sg;
3700         task->task_size = cmd->data_length;
3701         task->task_sg_nents = cmd->t_data_nents;
3702
3703         spin_lock_irqsave(&cmd->t_state_lock, flags);
3704         list_add_tail(&task->t_list, &cmd->t_task_list);
3705         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3706
3707         /* Success! Return number of tasks allocated */
3708         return 1;
3709 }
3710
3711 /*
3712  * Allocate any required ressources to execute the command, and either place
3713  * it on the execution queue if possible.  For writes we might not have the
3714  * payload yet, thus notify the fabric via a call to ->write_pending instead.
3715  */
3716 int transport_generic_new_cmd(struct se_cmd *cmd)
3717 {
3718         struct se_device *dev = cmd->se_dev;
3719         int task_cdbs, task_cdbs_bidi = 0;
3720         int set_counts = 1;
3721         int ret = 0;
3722
3723         /*
3724          * Determine is the TCM fabric module has already allocated physical
3725          * memory, and is directly calling transport_generic_map_mem_to_cmd()
3726          * beforehand.
3727          */
3728         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
3729             cmd->data_length) {
3730                 ret = transport_generic_get_mem(cmd);
3731                 if (ret < 0)
3732                         goto out_fail;
3733         }
3734
3735         /*
3736          * For BIDI command set up the read tasks first.
3737          */
3738         if (cmd->t_bidi_data_sg &&
3739             dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV) {
3740                 BUG_ON(!(cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB));
3741
3742                 task_cdbs_bidi = transport_allocate_data_tasks(cmd,
3743                                 DMA_FROM_DEVICE, cmd->t_bidi_data_sg,
3744                                 cmd->t_bidi_data_nents);
3745                 if (task_cdbs_bidi <= 0)
3746                         goto out_fail;
3747
3748                 atomic_inc(&cmd->t_fe_count);
3749                 atomic_inc(&cmd->t_se_count);
3750                 set_counts = 0;
3751         }
3752
3753         if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB) {
3754                 task_cdbs = transport_allocate_data_tasks(cmd,
3755                                         cmd->data_direction, cmd->t_data_sg,
3756                                         cmd->t_data_nents);
3757         } else {
3758                 task_cdbs = transport_allocate_control_task(cmd);
3759         }
3760
3761         if (task_cdbs <= 0)
3762                 goto out_fail;
3763
3764         if (set_counts) {
3765                 atomic_inc(&cmd->t_fe_count);
3766                 atomic_inc(&cmd->t_se_count);
3767         }
3768
3769         cmd->t_task_list_num = (task_cdbs + task_cdbs_bidi);
3770         atomic_set(&cmd->t_task_cdbs_left, cmd->t_task_list_num);
3771         atomic_set(&cmd->t_task_cdbs_ex_left, cmd->t_task_list_num);
3772
3773         /*
3774          * For WRITEs, let the fabric know its buffer is ready..
3775          * This WRITE struct se_cmd (and all of its associated struct se_task's)
3776          * will be added to the struct se_device execution queue after its WRITE
3777          * data has arrived. (ie: It gets handled by the transport processing
3778          * thread a second time)
3779          */
3780         if (cmd->data_direction == DMA_TO_DEVICE) {
3781                 transport_add_tasks_to_state_queue(cmd);
3782                 return transport_generic_write_pending(cmd);
3783         }
3784         /*
3785          * Everything else but a WRITE, add the struct se_cmd's struct se_task's
3786          * to the execution queue.
3787          */
3788         transport_execute_tasks(cmd);
3789         return 0;
3790
3791 out_fail:
3792         cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
3793         cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3794         return -EINVAL;
3795 }
3796 EXPORT_SYMBOL(transport_generic_new_cmd);
3797
3798 /*      transport_generic_process_write():
3799  *
3800  *
3801  */
3802 void transport_generic_process_write(struct se_cmd *cmd)
3803 {
3804         transport_execute_tasks(cmd);
3805 }
3806 EXPORT_SYMBOL(transport_generic_process_write);
3807
3808 static void transport_write_pending_qf(struct se_cmd *cmd)
3809 {
3810         int ret;
3811
3812         ret = cmd->se_tfo->write_pending(cmd);
3813         if (ret == -EAGAIN || ret == -ENOMEM) {
3814                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
3815                          cmd);
3816                 transport_handle_queue_full(cmd, cmd->se_dev);
3817         }
3818 }
3819
3820 static int transport_generic_write_pending(struct se_cmd *cmd)
3821 {
3822         unsigned long flags;
3823         int ret;
3824
3825         spin_lock_irqsave(&cmd->t_state_lock, flags);
3826         cmd->t_state = TRANSPORT_WRITE_PENDING;
3827         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3828
3829         /*
3830          * Clear the se_cmd for WRITE_PENDING status in order to set
3831          * cmd->t_transport_active=0 so that transport_generic_handle_data
3832          * can be called from HW target mode interrupt code.  This is safe
3833          * to be called with transport_off=1 before the cmd->se_tfo->write_pending
3834          * because the se_cmd->se_lun pointer is not being cleared.
3835          */
3836         transport_cmd_check_stop(cmd, 1, 0);
3837
3838         /*
3839          * Call the fabric write_pending function here to let the
3840          * frontend know that WRITE buffers are ready.
3841          */
3842         ret = cmd->se_tfo->write_pending(cmd);
3843         if (ret == -EAGAIN || ret == -ENOMEM)
3844                 goto queue_full;
3845         else if (ret < 0)
3846                 return ret;
3847
3848         return 1;
3849
3850 queue_full:
3851         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
3852         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
3853         transport_handle_queue_full(cmd, cmd->se_dev);
3854         return 0;
3855 }
3856
3857 /**
3858  * transport_release_cmd - free a command
3859  * @cmd:       command to free
3860  *
3861  * This routine unconditionally frees a command, and reference counting
3862  * or list removal must be done in the caller.
3863  */
3864 void transport_release_cmd(struct se_cmd *cmd)
3865 {
3866         BUG_ON(!cmd->se_tfo);
3867
3868         if (cmd->se_tmr_req)
3869                 core_tmr_release_req(cmd->se_tmr_req);
3870         if (cmd->t_task_cdb != cmd->__t_task_cdb)
3871                 kfree(cmd->t_task_cdb);
3872         /*
3873          * Check if target_wait_for_sess_cmds() is expecting to
3874          * release se_cmd directly here..
3875          */
3876         if (cmd->check_release != 0 && cmd->se_tfo->check_release_cmd)
3877                 if (cmd->se_tfo->check_release_cmd(cmd) != 0)
3878                         return;
3879
3880         cmd->se_tfo->release_cmd(cmd);
3881 }
3882 EXPORT_SYMBOL(transport_release_cmd);
3883
3884 void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
3885 {
3886         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
3887                 if (wait_for_tasks && cmd->se_tmr_req)
3888                          transport_wait_for_tasks(cmd);
3889
3890                 transport_release_cmd(cmd);
3891         } else {
3892                 if (wait_for_tasks)
3893                         transport_wait_for_tasks(cmd);
3894
3895                 core_dec_lacl_count(cmd->se_sess->se_node_acl, cmd);
3896
3897                 if (cmd->se_lun)
3898                         transport_lun_remove_cmd(cmd);
3899
3900                 transport_free_dev_tasks(cmd);
3901
3902                 transport_put_cmd(cmd);
3903         }
3904 }
3905 EXPORT_SYMBOL(transport_generic_free_cmd);
3906
3907 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
3908  * @se_sess:    session to reference
3909  * @se_cmd:     command descriptor to add
3910  */
3911 void target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
3912 {
3913         unsigned long flags;
3914
3915         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
3916         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
3917         se_cmd->check_release = 1;
3918         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
3919 }
3920 EXPORT_SYMBOL(target_get_sess_cmd);
3921
3922 /* target_put_sess_cmd - Check for active I/O shutdown or list delete
3923  * @se_sess:    session to reference
3924  * @se_cmd:     command descriptor to drop
3925  */
3926 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
3927 {
3928         unsigned long flags;
3929
3930         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
3931         if (list_empty(&se_cmd->se_cmd_list)) {
3932                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
3933                 WARN_ON(1);
3934                 return 0;
3935         }
3936
3937         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
3938                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
3939                 complete(&se_cmd->cmd_wait_comp);
3940                 return 1;
3941         }
3942         list_del(&se_cmd->se_cmd_list);
3943         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
3944
3945         return 0;
3946 }
3947 EXPORT_SYMBOL(target_put_sess_cmd);
3948
3949 /* target_splice_sess_cmd_list - Split active cmds into sess_wait_list
3950  * @se_sess:    session to split
3951  */
3952 void target_splice_sess_cmd_list(struct se_session *se_sess)
3953 {
3954         struct se_cmd *se_cmd;
3955         unsigned long flags;
3956
3957         WARN_ON(!list_empty(&se_sess->sess_wait_list));
3958         INIT_LIST_HEAD(&se_sess->sess_wait_list);
3959
3960         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
3961         se_sess->sess_tearing_down = 1;
3962
3963         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
3964
3965         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
3966                 se_cmd->cmd_wait_set = 1;
3967
3968         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
3969 }
3970 EXPORT_SYMBOL(target_splice_sess_cmd_list);
3971
3972 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
3973  * @se_sess:    session to wait for active I/O
3974  * @wait_for_tasks:     Make extra transport_wait_for_tasks call
3975  */
3976 void target_wait_for_sess_cmds(
3977         struct se_session *se_sess,
3978         int wait_for_tasks)
3979 {
3980         struct se_cmd *se_cmd, *tmp_cmd;
3981         bool rc = false;
3982
3983         list_for_each_entry_safe(se_cmd, tmp_cmd,
3984                                 &se_sess->sess_wait_list, se_cmd_list) {
3985                 list_del(&se_cmd->se_cmd_list);
3986
3987                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
3988                         " %d\n", se_cmd, se_cmd->t_state,
3989                         se_cmd->se_tfo->get_cmd_state(se_cmd));
3990
3991                 if (wait_for_tasks) {
3992                         pr_debug("Calling transport_wait_for_tasks se_cmd: %p t_state: %d,"
3993                                 " fabric state: %d\n", se_cmd, se_cmd->t_state,
3994                                 se_cmd->se_tfo->get_cmd_state(se_cmd));
3995
3996                         rc = transport_wait_for_tasks(se_cmd);
3997
3998                         pr_debug("After transport_wait_for_tasks se_cmd: %p t_state: %d,"
3999                                 " fabric state: %d\n", se_cmd, se_cmd->t_state,
4000                                 se_cmd->se_tfo->get_cmd_state(se_cmd));
4001                 }
4002
4003                 if (!rc) {
4004                         wait_for_completion(&se_cmd->cmd_wait_comp);
4005                         pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
4006                                 " fabric state: %d\n", se_cmd, se_cmd->t_state,
4007                                 se_cmd->se_tfo->get_cmd_state(se_cmd));
4008                 }
4009
4010                 se_cmd->se_tfo->release_cmd(se_cmd);
4011         }
4012 }
4013 EXPORT_SYMBOL(target_wait_for_sess_cmds);
4014
4015 /*      transport_lun_wait_for_tasks():
4016  *
4017  *      Called from ConfigFS context to stop the passed struct se_cmd to allow
4018  *      an struct se_lun to be successfully shutdown.
4019  */
4020 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
4021 {
4022         unsigned long flags;
4023         int ret;
4024         /*
4025          * If the frontend has already requested this struct se_cmd to
4026          * be stopped, we can safely ignore this struct se_cmd.
4027          */
4028         spin_lock_irqsave(&cmd->t_state_lock, flags);
4029         if (atomic_read(&cmd->t_transport_stop)) {
4030                 atomic_set(&cmd->transport_lun_stop, 0);
4031                 pr_debug("ConfigFS ITT[0x%08x] - t_transport_stop =="
4032                         " TRUE, skipping\n", cmd->se_tfo->get_task_tag(cmd));
4033                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4034                 transport_cmd_check_stop(cmd, 1, 0);
4035                 return -EPERM;
4036         }
4037         atomic_set(&cmd->transport_lun_fe_stop, 1);
4038         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4039
4040         wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
4041
4042         ret = transport_stop_tasks_for_cmd(cmd);
4043
4044         pr_debug("ConfigFS: cmd: %p t_tasks: %d stop tasks ret:"
4045                         " %d\n", cmd, cmd->t_task_list_num, ret);
4046         if (!ret) {
4047                 pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
4048                                 cmd->se_tfo->get_task_tag(cmd));
4049                 wait_for_completion(&cmd->transport_lun_stop_comp);
4050                 pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
4051                                 cmd->se_tfo->get_task_tag(cmd));
4052         }
4053         transport_remove_cmd_from_queue(cmd);
4054
4055         return 0;
4056 }
4057
4058 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
4059 {
4060         struct se_cmd *cmd = NULL;
4061         unsigned long lun_flags, cmd_flags;
4062         /*
4063          * Do exception processing and return CHECK_CONDITION status to the
4064          * Initiator Port.
4065          */
4066         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4067         while (!list_empty(&lun->lun_cmd_list)) {
4068                 cmd = list_first_entry(&lun->lun_cmd_list,
4069                        struct se_cmd, se_lun_node);
4070                 list_del(&cmd->se_lun_node);
4071
4072                 atomic_set(&cmd->transport_lun_active, 0);
4073                 /*
4074                  * This will notify iscsi_target_transport.c:
4075                  * transport_cmd_check_stop() that a LUN shutdown is in
4076                  * progress for the iscsi_cmd_t.
4077                  */
4078                 spin_lock(&cmd->t_state_lock);
4079                 pr_debug("SE_LUN[%d] - Setting cmd->transport"
4080                         "_lun_stop for  ITT: 0x%08x\n",
4081                         cmd->se_lun->unpacked_lun,
4082                         cmd->se_tfo->get_task_tag(cmd));
4083                 atomic_set(&cmd->transport_lun_stop, 1);
4084                 spin_unlock(&cmd->t_state_lock);
4085
4086                 spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
4087
4088                 if (!cmd->se_lun) {
4089                         pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
4090                                 cmd->se_tfo->get_task_tag(cmd),
4091                                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
4092                         BUG();
4093                 }
4094                 /*
4095                  * If the Storage engine still owns the iscsi_cmd_t, determine
4096                  * and/or stop its context.
4097                  */
4098                 pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
4099                         "_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
4100                         cmd->se_tfo->get_task_tag(cmd));
4101
4102                 if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
4103                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4104                         continue;
4105                 }
4106
4107                 pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
4108                         "_wait_for_tasks(): SUCCESS\n",
4109                         cmd->se_lun->unpacked_lun,
4110                         cmd->se_tfo->get_task_tag(cmd));
4111
4112                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
4113                 if (!atomic_read(&cmd->transport_dev_active)) {
4114                         spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4115                         goto check_cond;
4116                 }
4117                 atomic_set(&cmd->transport_dev_active, 0);
4118                 transport_all_task_dev_remove_state(cmd);
4119                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4120
4121                 transport_free_dev_tasks(cmd);
4122                 /*
4123                  * The Storage engine stopped this struct se_cmd before it was
4124                  * send to the fabric frontend for delivery back to the
4125                  * Initiator Node.  Return this SCSI CDB back with an
4126                  * CHECK_CONDITION status.
4127                  */
4128 check_cond:
4129                 transport_send_check_condition_and_sense(cmd,
4130                                 TCM_NON_EXISTENT_LUN, 0);
4131                 /*
4132                  *  If the fabric frontend is waiting for this iscsi_cmd_t to
4133                  * be released, notify the waiting thread now that LU has
4134                  * finished accessing it.
4135                  */
4136                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
4137                 if (atomic_read(&cmd->transport_lun_fe_stop)) {
4138                         pr_debug("SE_LUN[%d] - Detected FE stop for"
4139                                 " struct se_cmd: %p ITT: 0x%08x\n",
4140                                 lun->unpacked_lun,
4141                                 cmd, cmd->se_tfo->get_task_tag(cmd));
4142
4143                         spin_unlock_irqrestore(&cmd->t_state_lock,
4144                                         cmd_flags);
4145                         transport_cmd_check_stop(cmd, 1, 0);
4146                         complete(&cmd->transport_lun_fe_stop_comp);
4147                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4148                         continue;
4149                 }
4150                 pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
4151                         lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
4152
4153                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
4154                 spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
4155         }
4156         spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
4157 }
4158
4159 static int transport_clear_lun_thread(void *p)
4160 {
4161         struct se_lun *lun = (struct se_lun *)p;
4162
4163         __transport_clear_lun_from_sessions(lun);
4164         complete(&lun->lun_shutdown_comp);
4165
4166         return 0;
4167 }
4168
4169 int transport_clear_lun_from_sessions(struct se_lun *lun)
4170 {
4171         struct task_struct *kt;
4172
4173         kt = kthread_run(transport_clear_lun_thread, lun,
4174                         "tcm_cl_%u", lun->unpacked_lun);
4175         if (IS_ERR(kt)) {
4176                 pr_err("Unable to start clear_lun thread\n");
4177                 return PTR_ERR(kt);
4178         }
4179         wait_for_completion(&lun->lun_shutdown_comp);
4180
4181         return 0;
4182 }
4183
4184 /**
4185  * transport_wait_for_tasks - wait for completion to occur
4186  * @cmd:        command to wait
4187  *
4188  * Called from frontend fabric context to wait for storage engine
4189  * to pause and/or release frontend generated struct se_cmd.
4190  */
4191 bool transport_wait_for_tasks(struct se_cmd *cmd)
4192 {
4193         unsigned long flags;
4194
4195         spin_lock_irqsave(&cmd->t_state_lock, flags);
4196         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) && !(cmd->se_tmr_req)) {
4197                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4198                 return false;
4199         }
4200         /*
4201          * Only perform a possible wait_for_tasks if SCF_SUPPORTED_SAM_OPCODE
4202          * has been set in transport_set_supported_SAM_opcode().
4203          */
4204         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) && !cmd->se_tmr_req) {
4205                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4206                 return false;
4207         }
4208         /*
4209          * If we are already stopped due to an external event (ie: LUN shutdown)
4210          * sleep until the connection can have the passed struct se_cmd back.
4211          * The cmd->transport_lun_stopped_sem will be upped by
4212          * transport_clear_lun_from_sessions() once the ConfigFS context caller
4213          * has completed its operation on the struct se_cmd.
4214          */
4215         if (atomic_read(&cmd->transport_lun_stop)) {
4216
4217                 pr_debug("wait_for_tasks: Stopping"
4218                         " wait_for_completion(&cmd->t_tasktransport_lun_fe"
4219                         "_stop_comp); for ITT: 0x%08x\n",
4220                         cmd->se_tfo->get_task_tag(cmd));
4221                 /*
4222                  * There is a special case for WRITES where a FE exception +
4223                  * LUN shutdown means ConfigFS context is still sleeping on
4224                  * transport_lun_stop_comp in transport_lun_wait_for_tasks().
4225                  * We go ahead and up transport_lun_stop_comp just to be sure
4226                  * here.
4227                  */
4228                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4229                 complete(&cmd->transport_lun_stop_comp);
4230                 wait_for_completion(&cmd->transport_lun_fe_stop_comp);
4231                 spin_lock_irqsave(&cmd->t_state_lock, flags);
4232
4233                 transport_all_task_dev_remove_state(cmd);
4234                 /*
4235                  * At this point, the frontend who was the originator of this
4236                  * struct se_cmd, now owns the structure and can be released through
4237                  * normal means below.
4238                  */
4239                 pr_debug("wait_for_tasks: Stopped"
4240                         " wait_for_completion(&cmd->t_tasktransport_lun_fe_"
4241                         "stop_comp); for ITT: 0x%08x\n",
4242                         cmd->se_tfo->get_task_tag(cmd));
4243
4244                 atomic_set(&cmd->transport_lun_stop, 0);
4245         }
4246         if (!atomic_read(&cmd->t_transport_active) ||
4247              atomic_read(&cmd->t_transport_aborted)) {
4248                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4249                 return false;
4250         }
4251
4252         atomic_set(&cmd->t_transport_stop, 1);
4253
4254         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
4255                 " i_state: %d, t_state: %d, t_transport_stop = TRUE\n",
4256                 cmd, cmd->se_tfo->get_task_tag(cmd),
4257                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
4258
4259         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4260
4261         wake_up_interruptible(&cmd->se_dev->dev_queue_obj.thread_wq);
4262
4263         wait_for_completion(&cmd->t_transport_stop_comp);
4264
4265         spin_lock_irqsave(&cmd->t_state_lock, flags);
4266         atomic_set(&cmd->t_transport_active, 0);
4267         atomic_set(&cmd->t_transport_stop, 0);
4268
4269         pr_debug("wait_for_tasks: Stopped wait_for_compltion("
4270                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
4271                 cmd->se_tfo->get_task_tag(cmd));
4272
4273         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4274
4275         return true;
4276 }
4277 EXPORT_SYMBOL(transport_wait_for_tasks);
4278
4279 static int transport_get_sense_codes(
4280         struct se_cmd *cmd,
4281         u8 *asc,
4282         u8 *ascq)
4283 {
4284         *asc = cmd->scsi_asc;
4285         *ascq = cmd->scsi_ascq;
4286
4287         return 0;
4288 }
4289
4290 static int transport_set_sense_codes(
4291         struct se_cmd *cmd,
4292         u8 asc,
4293         u8 ascq)
4294 {
4295         cmd->scsi_asc = asc;
4296         cmd->scsi_ascq = ascq;
4297
4298         return 0;
4299 }
4300
4301 int transport_send_check_condition_and_sense(
4302         struct se_cmd *cmd,
4303         u8 reason,
4304         int from_transport)
4305 {
4306         unsigned char *buffer = cmd->sense_buffer;
4307         unsigned long flags;
4308         int offset;
4309         u8 asc = 0, ascq = 0;
4310
4311         spin_lock_irqsave(&cmd->t_state_lock, flags);
4312         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
4313                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4314                 return 0;
4315         }
4316         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
4317         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4318
4319         if (!reason && from_transport)
4320                 goto after_reason;
4321
4322         if (!from_transport)
4323                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
4324         /*
4325          * Data Segment and SenseLength of the fabric response PDU.
4326          *
4327          * TRANSPORT_SENSE_BUFFER is now set to SCSI_SENSE_BUFFERSIZE
4328          * from include/scsi/scsi_cmnd.h
4329          */
4330         offset = cmd->se_tfo->set_fabric_sense_len(cmd,
4331                                 TRANSPORT_SENSE_BUFFER);
4332         /*
4333          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
4334          * SENSE KEY values from include/scsi/scsi.h
4335          */
4336         switch (reason) {
4337         case TCM_NON_EXISTENT_LUN:
4338                 /* CURRENT ERROR */
4339                 buffer[offset] = 0x70;
4340                 /* ILLEGAL REQUEST */
4341                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4342                 /* LOGICAL UNIT NOT SUPPORTED */
4343                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x25;
4344                 break;
4345         case TCM_UNSUPPORTED_SCSI_OPCODE:
4346         case TCM_SECTOR_COUNT_TOO_MANY:
4347                 /* CURRENT ERROR */
4348                 buffer[offset] = 0x70;
4349                 /* ILLEGAL REQUEST */
4350                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4351                 /* INVALID COMMAND OPERATION CODE */
4352                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x20;
4353                 break;
4354         case TCM_UNKNOWN_MODE_PAGE:
4355                 /* CURRENT ERROR */
4356                 buffer[offset] = 0x70;
4357                 /* ILLEGAL REQUEST */
4358                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4359                 /* INVALID FIELD IN CDB */
4360                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
4361                 break;
4362         case TCM_CHECK_CONDITION_ABORT_CMD:
4363                 /* CURRENT ERROR */
4364                 buffer[offset] = 0x70;
4365                 /* ABORTED COMMAND */
4366                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4367                 /* BUS DEVICE RESET FUNCTION OCCURRED */
4368                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x29;
4369                 buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x03;
4370                 break;
4371         case TCM_INCORRECT_AMOUNT_OF_DATA:
4372                 /* CURRENT ERROR */
4373                 buffer[offset] = 0x70;
4374                 /* ABORTED COMMAND */
4375                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4376                 /* WRITE ERROR */
4377                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x0c;
4378                 /* NOT ENOUGH UNSOLICITED DATA */
4379                 buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0d;
4380                 break;
4381         case TCM_INVALID_CDB_FIELD:
4382                 /* CURRENT ERROR */
4383                 buffer[offset] = 0x70;
4384                 /* ABORTED COMMAND */
4385                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4386                 /* INVALID FIELD IN CDB */
4387                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x24;
4388                 break;
4389         case TCM_INVALID_PARAMETER_LIST:
4390                 /* CURRENT ERROR */
4391                 buffer[offset] = 0x70;
4392                 /* ABORTED COMMAND */
4393                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4394                 /* INVALID FIELD IN PARAMETER LIST */
4395                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x26;
4396                 break;
4397         case TCM_UNEXPECTED_UNSOLICITED_DATA:
4398                 /* CURRENT ERROR */
4399                 buffer[offset] = 0x70;
4400                 /* ABORTED COMMAND */
4401                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4402                 /* WRITE ERROR */
4403                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x0c;
4404                 /* UNEXPECTED_UNSOLICITED_DATA */
4405                 buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x0c;
4406                 break;
4407         case TCM_SERVICE_CRC_ERROR:
4408                 /* CURRENT ERROR */
4409                 buffer[offset] = 0x70;
4410                 /* ABORTED COMMAND */
4411                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4412                 /* PROTOCOL SERVICE CRC ERROR */
4413                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x47;
4414                 /* N/A */
4415                 buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x05;
4416                 break;
4417         case TCM_SNACK_REJECTED:
4418                 /* CURRENT ERROR */
4419                 buffer[offset] = 0x70;
4420                 /* ABORTED COMMAND */
4421                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
4422                 /* READ ERROR */
4423                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x11;
4424                 /* FAILED RETRANSMISSION REQUEST */
4425                 buffer[offset+SPC_ASCQ_KEY_OFFSET] = 0x13;
4426                 break;
4427         case TCM_WRITE_PROTECTED:
4428                 /* CURRENT ERROR */
4429                 buffer[offset] = 0x70;
4430                 /* DATA PROTECT */
4431                 buffer[offset+SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
4432                 /* WRITE PROTECTED */
4433                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x27;
4434                 break;
4435         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
4436                 /* CURRENT ERROR */
4437                 buffer[offset] = 0x70;
4438                 /* UNIT ATTENTION */
4439                 buffer[offset+SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
4440                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
4441                 buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
4442                 buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
4443                 break;
4444         case TCM_CHECK_CONDITION_NOT_READY:
4445                 /* CURRENT ERROR */
4446                 buffer[offset] = 0x70;
4447                 /* Not Ready */
4448                 buffer[offset+SPC_SENSE_KEY_OFFSET] = NOT_READY;
4449                 transport_get_sense_codes(cmd, &asc, &ascq);
4450                 buffer[offset+SPC_ASC_KEY_OFFSET] = asc;
4451                 buffer[offset+SPC_ASCQ_KEY_OFFSET] = ascq;
4452                 break;
4453         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
4454         default:
4455                 /* CURRENT ERROR */
4456                 buffer[offset] = 0x70;
4457                 /* ILLEGAL REQUEST */
4458                 buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
4459                 /* LOGICAL UNIT COMMUNICATION FAILURE */
4460                 buffer[offset+SPC_ASC_KEY_OFFSET] = 0x80;
4461                 break;
4462         }
4463         /*
4464          * This code uses linux/include/scsi/scsi.h SAM status codes!
4465          */
4466         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
4467         /*
4468          * Automatically padded, this value is encoded in the fabric's
4469          * data_length response PDU containing the SCSI defined sense data.
4470          */
4471         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER + offset;
4472
4473 after_reason:
4474         return cmd->se_tfo->queue_status(cmd);
4475 }
4476 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
4477
4478 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
4479 {
4480         int ret = 0;
4481
4482         if (atomic_read(&cmd->t_transport_aborted) != 0) {
4483                 if (!send_status ||
4484                      (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
4485                         return 1;
4486 #if 0
4487                 pr_debug("Sending delayed SAM_STAT_TASK_ABORTED"
4488                         " status for CDB: 0x%02x ITT: 0x%08x\n",
4489                         cmd->t_task_cdb[0],
4490                         cmd->se_tfo->get_task_tag(cmd));
4491 #endif
4492                 cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
4493                 cmd->se_tfo->queue_status(cmd);
4494                 ret = 1;
4495         }
4496         return ret;
4497 }
4498 EXPORT_SYMBOL(transport_check_aborted_status);
4499
4500 void transport_send_task_abort(struct se_cmd *cmd)
4501 {
4502         unsigned long flags;
4503
4504         spin_lock_irqsave(&cmd->t_state_lock, flags);
4505         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
4506                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4507                 return;
4508         }
4509         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
4510
4511         /*
4512          * If there are still expected incoming fabric WRITEs, we wait
4513          * until until they have completed before sending a TASK_ABORTED
4514          * response.  This response with TASK_ABORTED status will be
4515          * queued back to fabric module by transport_check_aborted_status().
4516          */
4517         if (cmd->data_direction == DMA_TO_DEVICE) {
4518                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
4519                         atomic_inc(&cmd->t_transport_aborted);
4520                         smp_mb__after_atomic_inc();
4521                 }
4522         }
4523         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
4524 #if 0
4525         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
4526                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
4527                 cmd->se_tfo->get_task_tag(cmd));
4528 #endif
4529         cmd->se_tfo->queue_status(cmd);
4530 }
4531
4532 /*      transport_generic_do_tmr():
4533  *
4534  *
4535  */
4536 int transport_generic_do_tmr(struct se_cmd *cmd)
4537 {
4538         struct se_device *dev = cmd->se_dev;
4539         struct se_tmr_req *tmr = cmd->se_tmr_req;
4540         int ret;
4541
4542         switch (tmr->function) {
4543         case TMR_ABORT_TASK:
4544                 tmr->response = TMR_FUNCTION_REJECTED;
4545                 break;
4546         case TMR_ABORT_TASK_SET:
4547         case TMR_CLEAR_ACA:
4548         case TMR_CLEAR_TASK_SET:
4549                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
4550                 break;
4551         case TMR_LUN_RESET:
4552                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
4553                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
4554                                          TMR_FUNCTION_REJECTED;
4555                 break;
4556         case TMR_TARGET_WARM_RESET:
4557                 tmr->response = TMR_FUNCTION_REJECTED;
4558                 break;
4559         case TMR_TARGET_COLD_RESET:
4560                 tmr->response = TMR_FUNCTION_REJECTED;
4561                 break;
4562         default:
4563                 pr_err("Uknown TMR function: 0x%02x.\n",
4564                                 tmr->function);
4565                 tmr->response = TMR_FUNCTION_REJECTED;
4566                 break;
4567         }
4568
4569         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
4570         cmd->se_tfo->queue_tm_rsp(cmd);
4571
4572         transport_cmd_check_stop_to_fabric(cmd);
4573         return 0;
4574 }
4575
4576 /*      transport_processing_thread():
4577  *
4578  *
4579  */
4580 static int transport_processing_thread(void *param)
4581 {
4582         int ret;
4583         struct se_cmd *cmd;
4584         struct se_device *dev = (struct se_device *) param;
4585
4586         while (!kthread_should_stop()) {
4587                 ret = wait_event_interruptible(dev->dev_queue_obj.thread_wq,
4588                                 atomic_read(&dev->dev_queue_obj.queue_cnt) ||
4589                                 kthread_should_stop());
4590                 if (ret < 0)
4591                         goto out;
4592
4593 get_cmd:
4594                 __transport_execute_tasks(dev);
4595
4596                 cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj);
4597                 if (!cmd)
4598                         continue;
4599
4600                 switch (cmd->t_state) {
4601                 case TRANSPORT_NEW_CMD:
4602                         BUG();
4603                         break;
4604                 case TRANSPORT_NEW_CMD_MAP:
4605                         if (!cmd->se_tfo->new_cmd_map) {
4606                                 pr_err("cmd->se_tfo->new_cmd_map is"
4607                                         " NULL for TRANSPORT_NEW_CMD_MAP\n");
4608                                 BUG();
4609                         }
4610                         ret = cmd->se_tfo->new_cmd_map(cmd);
4611                         if (ret < 0) {
4612                                 transport_generic_request_failure(cmd);
4613                                 break;
4614                         }
4615                         ret = transport_generic_new_cmd(cmd);
4616                         if (ret < 0) {
4617                                 transport_generic_request_failure(cmd);
4618                                 break;
4619                         }
4620                         break;
4621                 case TRANSPORT_PROCESS_WRITE:
4622                         transport_generic_process_write(cmd);
4623                         break;
4624                 case TRANSPORT_PROCESS_TMR:
4625                         transport_generic_do_tmr(cmd);
4626                         break;
4627                 case TRANSPORT_COMPLETE_QF_WP:
4628                         transport_write_pending_qf(cmd);
4629                         break;
4630                 case TRANSPORT_COMPLETE_QF_OK:
4631                         transport_complete_qf(cmd);
4632                         break;
4633                 default:
4634                         pr_err("Unknown t_state: %d  for ITT: 0x%08x "
4635                                 "i_state: %d on SE LUN: %u\n",
4636                                 cmd->t_state,
4637                                 cmd->se_tfo->get_task_tag(cmd),
4638                                 cmd->se_tfo->get_cmd_state(cmd),
4639                                 cmd->se_lun->unpacked_lun);
4640                         BUG();
4641                 }
4642
4643                 goto get_cmd;
4644         }
4645
4646 out:
4647         WARN_ON(!list_empty(&dev->state_task_list));
4648         WARN_ON(!list_empty(&dev->dev_queue_obj.qobj_list));
4649         dev->process_thread = NULL;
4650         return 0;
4651 }