source: src/linux/universal/linux-4.4/drivers/target/target_core_transport.c @ 31662

Last change on this file since 31662 was 31662, checked in by brainslayer, 4 months ago

use new squashfs in all kernels

File size: 85.0 KB
Line 
1/*******************************************************************************
2 * Filename:  target_core_transport.c
3 *
4 * This file contains the Generic Target Engine Core.
5 *
6 * (c) Copyright 2002-2013 Datera, Inc.
7 *
8 * Nicholas A. Bellinger <nab@kernel.org>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 *
24 ******************************************************************************/
25
26#include <linux/net.h>
27#include <linux/delay.h>
28#include <linux/string.h>
29#include <linux/timer.h>
30#include <linux/slab.h>
31#include <linux/spinlock.h>
32#include <linux/kthread.h>
33#include <linux/in.h>
34#include <linux/cdrom.h>
35#include <linux/module.h>
36#include <linux/ratelimit.h>
37#include <linux/vmalloc.h>
38#include <asm/unaligned.h>
39#include <net/sock.h>
40#include <net/tcp.h>
41#include <scsi/scsi_proto.h>
42#include <scsi/scsi_common.h>
43
44#include <target/target_core_base.h>
45#include <target/target_core_backend.h>
46#include <target/target_core_fabric.h>
47
48#include "target_core_internal.h"
49#include "target_core_alua.h"
50#include "target_core_pr.h"
51#include "target_core_ua.h"
52
53#define CREATE_TRACE_POINTS
54#include <trace/events/target.h>
55
56static struct workqueue_struct *target_completion_wq;
57static struct kmem_cache *se_sess_cache;
58struct kmem_cache *se_ua_cache;
59struct kmem_cache *t10_pr_reg_cache;
60struct kmem_cache *t10_alua_lu_gp_cache;
61struct kmem_cache *t10_alua_lu_gp_mem_cache;
62struct kmem_cache *t10_alua_tg_pt_gp_cache;
63struct kmem_cache *t10_alua_lba_map_cache;
64struct kmem_cache *t10_alua_lba_map_mem_cache;
65
66static void transport_complete_task_attr(struct se_cmd *cmd);
67static void transport_handle_queue_full(struct se_cmd *cmd,
68                struct se_device *dev);
69static int transport_put_cmd(struct se_cmd *cmd);
70static void target_complete_ok_work(struct work_struct *work);
71
72int init_se_kmem_caches(void)
73{
74        se_sess_cache = kmem_cache_create("se_sess_cache",
75                        sizeof(struct se_session), __alignof__(struct se_session),
76                        0, NULL);
77        if (!se_sess_cache) {
78                pr_err("kmem_cache_create() for struct se_session"
79                                " failed\n");
80                goto out;
81        }
82        se_ua_cache = kmem_cache_create("se_ua_cache",
83                        sizeof(struct se_ua), __alignof__(struct se_ua),
84                        0, NULL);
85        if (!se_ua_cache) {
86                pr_err("kmem_cache_create() for struct se_ua failed\n");
87                goto out_free_sess_cache;
88        }
89        t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
90                        sizeof(struct t10_pr_registration),
91                        __alignof__(struct t10_pr_registration), 0, NULL);
92        if (!t10_pr_reg_cache) {
93                pr_err("kmem_cache_create() for struct t10_pr_registration"
94                                " failed\n");
95                goto out_free_ua_cache;
96        }
97        t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
98                        sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
99                        0, NULL);
100        if (!t10_alua_lu_gp_cache) {
101                pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
102                                " failed\n");
103                goto out_free_pr_reg_cache;
104        }
105        t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
106                        sizeof(struct t10_alua_lu_gp_member),
107                        __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
108        if (!t10_alua_lu_gp_mem_cache) {
109                pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
110                                "cache failed\n");
111                goto out_free_lu_gp_cache;
112        }
113        t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
114                        sizeof(struct t10_alua_tg_pt_gp),
115                        __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
116        if (!t10_alua_tg_pt_gp_cache) {
117                pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
118                                "cache failed\n");
119                goto out_free_lu_gp_mem_cache;
120        }
121        t10_alua_lba_map_cache = kmem_cache_create(
122                        "t10_alua_lba_map_cache",
123                        sizeof(struct t10_alua_lba_map),
124                        __alignof__(struct t10_alua_lba_map), 0, NULL);
125        if (!t10_alua_lba_map_cache) {
126                pr_err("kmem_cache_create() for t10_alua_lba_map_"
127                                "cache failed\n");
128                goto out_free_tg_pt_gp_cache;
129        }
130        t10_alua_lba_map_mem_cache = kmem_cache_create(
131                        "t10_alua_lba_map_mem_cache",
132                        sizeof(struct t10_alua_lba_map_member),
133                        __alignof__(struct t10_alua_lba_map_member), 0, NULL);
134        if (!t10_alua_lba_map_mem_cache) {
135                pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
136                                "cache failed\n");
137                goto out_free_lba_map_cache;
138        }
139
140        target_completion_wq = alloc_workqueue("target_completion",
141                                               WQ_MEM_RECLAIM, 0);
142        if (!target_completion_wq)
143                goto out_free_lba_map_mem_cache;
144
145        return 0;
146
147out_free_lba_map_mem_cache:
148        kmem_cache_destroy(t10_alua_lba_map_mem_cache);
149out_free_lba_map_cache:
150        kmem_cache_destroy(t10_alua_lba_map_cache);
151out_free_tg_pt_gp_cache:
152        kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
153out_free_lu_gp_mem_cache:
154        kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
155out_free_lu_gp_cache:
156        kmem_cache_destroy(t10_alua_lu_gp_cache);
157out_free_pr_reg_cache:
158        kmem_cache_destroy(t10_pr_reg_cache);
159out_free_ua_cache:
160        kmem_cache_destroy(se_ua_cache);
161out_free_sess_cache:
162        kmem_cache_destroy(se_sess_cache);
163out:
164        return -ENOMEM;
165}
166
167void release_se_kmem_caches(void)
168{
169        destroy_workqueue(target_completion_wq);
170        kmem_cache_destroy(se_sess_cache);
171        kmem_cache_destroy(se_ua_cache);
172        kmem_cache_destroy(t10_pr_reg_cache);
173        kmem_cache_destroy(t10_alua_lu_gp_cache);
174        kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
175        kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
176        kmem_cache_destroy(t10_alua_lba_map_cache);
177        kmem_cache_destroy(t10_alua_lba_map_mem_cache);
178}
179
180/* This code ensures unique mib indexes are handed out. */
181static DEFINE_SPINLOCK(scsi_mib_index_lock);
182static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
183
184/*
185 * Allocate a new row index for the entry type specified
186 */
187u32 scsi_get_new_index(scsi_index_t type)
188{
189        u32 new_index;
190
191        BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
192
193        spin_lock(&scsi_mib_index_lock);
194        new_index = ++scsi_mib_index[type];
195        spin_unlock(&scsi_mib_index_lock);
196
197        return new_index;
198}
199
200void transport_subsystem_check_init(void)
201{
202        int ret;
203        static int sub_api_initialized;
204
205        if (sub_api_initialized)
206                return;
207
208        ret = request_module("target_core_iblock");
209        if (ret != 0)
210                pr_err("Unable to load target_core_iblock\n");
211
212        ret = request_module("target_core_file");
213        if (ret != 0)
214                pr_err("Unable to load target_core_file\n");
215
216        ret = request_module("target_core_pscsi");
217        if (ret != 0)
218                pr_err("Unable to load target_core_pscsi\n");
219
220        ret = request_module("target_core_user");
221        if (ret != 0)
222                pr_err("Unable to load target_core_user\n");
223
224        sub_api_initialized = 1;
225}
226
227struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
228{
229        struct se_session *se_sess;
230
231        se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
232        if (!se_sess) {
233                pr_err("Unable to allocate struct se_session from"
234                                " se_sess_cache\n");
235                return ERR_PTR(-ENOMEM);
236        }
237        INIT_LIST_HEAD(&se_sess->sess_list);
238        INIT_LIST_HEAD(&se_sess->sess_acl_list);
239        INIT_LIST_HEAD(&se_sess->sess_cmd_list);
240        INIT_LIST_HEAD(&se_sess->sess_wait_list);
241        spin_lock_init(&se_sess->sess_cmd_lock);
242        kref_init(&se_sess->sess_kref);
243        se_sess->sup_prot_ops = sup_prot_ops;
244
245        return se_sess;
246}
247EXPORT_SYMBOL(transport_init_session);
248
249int transport_alloc_session_tags(struct se_session *se_sess,
250                                 unsigned int tag_num, unsigned int tag_size)
251{
252        int rc;
253
254        se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
255                                        GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
256        if (!se_sess->sess_cmd_map) {
257                se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
258                if (!se_sess->sess_cmd_map) {
259                        pr_err("Unable to allocate se_sess->sess_cmd_map\n");
260                        return -ENOMEM;
261                }
262        }
263
264        rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
265        if (rc < 0) {
266                pr_err("Unable to init se_sess->sess_tag_pool,"
267                        " tag_num: %u\n", tag_num);
268                kvfree(se_sess->sess_cmd_map);
269                se_sess->sess_cmd_map = NULL;
270                return -ENOMEM;
271        }
272
273        return 0;
274}
275EXPORT_SYMBOL(transport_alloc_session_tags);
276
277struct se_session *transport_init_session_tags(unsigned int tag_num,
278                                               unsigned int tag_size,
279                                               enum target_prot_op sup_prot_ops)
280{
281        struct se_session *se_sess;
282        int rc;
283
284        se_sess = transport_init_session(sup_prot_ops);
285        if (IS_ERR(se_sess))
286                return se_sess;
287
288        rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
289        if (rc < 0) {
290                transport_free_session(se_sess);
291                return ERR_PTR(-ENOMEM);
292        }
293
294        return se_sess;
295}
296EXPORT_SYMBOL(transport_init_session_tags);
297
298/*
299 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
300 */
301void __transport_register_session(
302        struct se_portal_group *se_tpg,
303        struct se_node_acl *se_nacl,
304        struct se_session *se_sess,
305        void *fabric_sess_ptr)
306{
307        const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
308        unsigned char buf[PR_REG_ISID_LEN];
309
310        se_sess->se_tpg = se_tpg;
311        se_sess->fabric_sess_ptr = fabric_sess_ptr;
312        /*
313         * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
314         *
315         * Only set for struct se_session's that will actually be moving I/O.
316         * eg: *NOT* discovery sessions.
317         */
318        if (se_nacl) {
319                /*
320                 *
321                 * Determine if fabric allows for T10-PI feature bits exposed to
322                 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
323                 *
324                 * If so, then always save prot_type on a per se_node_acl node
325                 * basis and re-instate the previous sess_prot_type to avoid
326                 * disabling PI from below any previously initiator side
327                 * registered LUNs.
328                 */
329                if (se_nacl->saved_prot_type)
330                        se_sess->sess_prot_type = se_nacl->saved_prot_type;
331                else if (tfo->tpg_check_prot_fabric_only)
332                        se_sess->sess_prot_type = se_nacl->saved_prot_type =
333                                        tfo->tpg_check_prot_fabric_only(se_tpg);
334                /*
335                 * If the fabric module supports an ISID based TransportID,
336                 * save this value in binary from the fabric I_T Nexus now.
337                 */
338                if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
339                        memset(&buf[0], 0, PR_REG_ISID_LEN);
340                        se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
341                                        &buf[0], PR_REG_ISID_LEN);
342                        se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
343                }
344
345                spin_lock_irq(&se_nacl->nacl_sess_lock);
346                /*
347                 * The se_nacl->nacl_sess pointer will be set to the
348                 * last active I_T Nexus for each struct se_node_acl.
349                 */
350                se_nacl->nacl_sess = se_sess;
351
352                list_add_tail(&se_sess->sess_acl_list,
353                              &se_nacl->acl_sess_list);
354                spin_unlock_irq(&se_nacl->nacl_sess_lock);
355        }
356        list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
357
358        pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
359                se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
360}
361EXPORT_SYMBOL(__transport_register_session);
362
363void transport_register_session(
364        struct se_portal_group *se_tpg,
365        struct se_node_acl *se_nacl,
366        struct se_session *se_sess,
367        void *fabric_sess_ptr)
368{
369        unsigned long flags;
370
371        spin_lock_irqsave(&se_tpg->session_lock, flags);
372        __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
373        spin_unlock_irqrestore(&se_tpg->session_lock, flags);
374}
375EXPORT_SYMBOL(transport_register_session);
376
377static void target_release_session(struct kref *kref)
378{
379        struct se_session *se_sess = container_of(kref,
380                        struct se_session, sess_kref);
381        struct se_portal_group *se_tpg = se_sess->se_tpg;
382
383        se_tpg->se_tpg_tfo->close_session(se_sess);
384}
385
386void target_get_session(struct se_session *se_sess)
387{
388        kref_get(&se_sess->sess_kref);
389}
390EXPORT_SYMBOL(target_get_session);
391
392void target_put_session(struct se_session *se_sess)
393{
394        kref_put(&se_sess->sess_kref, target_release_session);
395}
396EXPORT_SYMBOL(target_put_session);
397
398ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
399{
400        struct se_session *se_sess;
401        ssize_t len = 0;
402
403        spin_lock_bh(&se_tpg->session_lock);
404        list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
405                if (!se_sess->se_node_acl)
406                        continue;
407                if (!se_sess->se_node_acl->dynamic_node_acl)
408                        continue;
409                if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
410                        break;
411
412                len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
413                                se_sess->se_node_acl->initiatorname);
414                len += 1; /* Include NULL terminator */
415        }
416        spin_unlock_bh(&se_tpg->session_lock);
417
418        return len;
419}
420EXPORT_SYMBOL(target_show_dynamic_sessions);
421
422static void target_complete_nacl(struct kref *kref)
423{
424        struct se_node_acl *nacl = container_of(kref,
425                                struct se_node_acl, acl_kref);
426        struct se_portal_group *se_tpg = nacl->se_tpg;
427
428        if (!nacl->dynamic_stop) {
429                complete(&nacl->acl_free_comp);
430                return;
431        }
432
433        mutex_lock(&se_tpg->acl_node_mutex);
434        list_del(&nacl->acl_list);
435        mutex_unlock(&se_tpg->acl_node_mutex);
436
437        core_tpg_wait_for_nacl_pr_ref(nacl);
438        core_free_device_list_for_node(nacl, se_tpg);
439        kfree(nacl);
440}
441
442void target_put_nacl(struct se_node_acl *nacl)
443{
444        kref_put(&nacl->acl_kref, target_complete_nacl);
445}
446EXPORT_SYMBOL(target_put_nacl);
447
448void transport_deregister_session_configfs(struct se_session *se_sess)
449{
450        struct se_node_acl *se_nacl;
451        unsigned long flags;
452        /*
453         * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
454         */
455        se_nacl = se_sess->se_node_acl;
456        if (se_nacl) {
457                spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
458                if (se_nacl->acl_stop == 0)
459                        list_del(&se_sess->sess_acl_list);
460                /*
461                 * If the session list is empty, then clear the pointer.
462                 * Otherwise, set the struct se_session pointer from the tail
463                 * element of the per struct se_node_acl active session list.
464                 */
465                if (list_empty(&se_nacl->acl_sess_list))
466                        se_nacl->nacl_sess = NULL;
467                else {
468                        se_nacl->nacl_sess = container_of(
469                                        se_nacl->acl_sess_list.prev,
470                                        struct se_session, sess_acl_list);
471                }
472                spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
473        }
474}
475EXPORT_SYMBOL(transport_deregister_session_configfs);
476
477void transport_free_session(struct se_session *se_sess)
478{
479        struct se_node_acl *se_nacl = se_sess->se_node_acl;
480
481        /*
482         * Drop the se_node_acl->nacl_kref obtained from within
483         * core_tpg_get_initiator_node_acl().
484         */
485        if (se_nacl) {
486                struct se_portal_group *se_tpg = se_nacl->se_tpg;
487                const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
488                unsigned long flags;
489
490                se_sess->se_node_acl = NULL;
491
492                /*
493                 * Also determine if we need to drop the extra ->cmd_kref if
494                 * it had been previously dynamically generated, and
495                 * the endpoint is not caching dynamic ACLs.
496                 */
497                mutex_lock(&se_tpg->acl_node_mutex);
498                if (se_nacl->dynamic_node_acl &&
499                    !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
500                        spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
501                        if (list_empty(&se_nacl->acl_sess_list))
502                                se_nacl->dynamic_stop = true;
503                        spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
504
505                        if (se_nacl->dynamic_stop)
506                                list_del(&se_nacl->acl_list);
507                }
508                mutex_unlock(&se_tpg->acl_node_mutex);
509
510                if (se_nacl->dynamic_stop)
511                        target_put_nacl(se_nacl);
512
513                target_put_nacl(se_nacl);
514        }
515        if (se_sess->sess_cmd_map) {
516                percpu_ida_destroy(&se_sess->sess_tag_pool);
517                kvfree(se_sess->sess_cmd_map);
518        }
519        kmem_cache_free(se_sess_cache, se_sess);
520}
521EXPORT_SYMBOL(transport_free_session);
522
523void transport_deregister_session(struct se_session *se_sess)
524{
525        struct se_portal_group *se_tpg = se_sess->se_tpg;
526        unsigned long flags;
527
528        if (!se_tpg) {
529                transport_free_session(se_sess);
530                return;
531        }
532
533        spin_lock_irqsave(&se_tpg->session_lock, flags);
534        list_del(&se_sess->sess_list);
535        se_sess->se_tpg = NULL;
536        se_sess->fabric_sess_ptr = NULL;
537        spin_unlock_irqrestore(&se_tpg->session_lock, flags);
538
539        pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
540                se_tpg->se_tpg_tfo->get_fabric_name());
541        /*
542         * If last kref is dropping now for an explicit NodeACL, awake sleeping
543         * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
544         * removal context from within transport_free_session() code.
545         *
546         * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
547         * to release all remaining generate_node_acl=1 created ACL resources.
548         */
549
550        transport_free_session(se_sess);
551}
552EXPORT_SYMBOL(transport_deregister_session);
553
554static void target_remove_from_state_list(struct se_cmd *cmd)
555{
556        struct se_device *dev = cmd->se_dev;
557        unsigned long flags;
558
559        if (!dev)
560                return;
561
562        if (cmd->transport_state & CMD_T_BUSY)
563                return;
564
565        spin_lock_irqsave(&dev->execute_task_lock, flags);
566        if (cmd->state_active) {
567                list_del(&cmd->state_list);
568                cmd->state_active = false;
569        }
570        spin_unlock_irqrestore(&dev->execute_task_lock, flags);
571}
572
573static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
574                                    bool write_pending)
575{
576        unsigned long flags;
577
578        if (remove_from_lists) {
579                target_remove_from_state_list(cmd);
580
581                /*
582                 * Clear struct se_cmd->se_lun before the handoff to FE.
583                 */
584                cmd->se_lun = NULL;
585        }
586
587        spin_lock_irqsave(&cmd->t_state_lock, flags);
588        if (write_pending)
589                cmd->t_state = TRANSPORT_WRITE_PENDING;
590
591        /*
592         * Determine if frontend context caller is requesting the stopping of
593         * this command for frontend exceptions.
594         */
595        if (cmd->transport_state & CMD_T_STOP) {
596                pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
597                        __func__, __LINE__, cmd->tag);
598
599                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
600
601                complete_all(&cmd->t_transport_stop_comp);
602                return 1;
603        }
604
605        cmd->transport_state &= ~CMD_T_ACTIVE;
606        if (remove_from_lists) {
607                /*
608                 * Some fabric modules like tcm_loop can release
609                 * their internally allocated I/O reference now and
610                 * struct se_cmd now.
611                 *
612                 * Fabric modules are expected to return '1' here if the
613                 * se_cmd being passed is released at this point,
614                 * or zero if not being released.
615                 */
616                if (cmd->se_tfo->check_stop_free != NULL) {
617                        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
618                        return cmd->se_tfo->check_stop_free(cmd);
619                }
620        }
621
622        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
623        return 0;
624}
625
626static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
627{
628        return transport_cmd_check_stop(cmd, true, false);
629}
630
631static void transport_lun_remove_cmd(struct se_cmd *cmd)
632{
633        struct se_lun *lun = cmd->se_lun;
634
635        if (!lun)
636                return;
637
638        if (cmpxchg(&cmd->lun_ref_active, true, false))
639                percpu_ref_put(&lun->lun_ref);
640}
641
642void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
643{
644        bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF);
645
646        if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
647                transport_lun_remove_cmd(cmd);
648        /*
649         * Allow the fabric driver to unmap any resources before
650         * releasing the descriptor via TFO->release_cmd()
651         */
652        if (remove)
653                cmd->se_tfo->aborted_task(cmd);
654
655        if (transport_cmd_check_stop_to_fabric(cmd))
656                return;
657        if (remove && ack_kref)
658                transport_put_cmd(cmd);
659}
660
661static void target_complete_failure_work(struct work_struct *work)
662{
663        struct se_cmd *cmd = container_of(work, struct se_cmd, work);
664
665        transport_generic_request_failure(cmd,
666                        TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
667}
668
669/*
670 * Used when asking transport to copy Sense Data from the underlying
671 * Linux/SCSI struct scsi_cmnd
672 */
673static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
674{
675        struct se_device *dev = cmd->se_dev;
676
677        WARN_ON(!cmd->se_lun);
678
679        if (!dev)
680                return NULL;
681
682        if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
683                return NULL;
684
685        cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
686
687        pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
688                dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
689        return cmd->sense_buffer;
690}
691
692void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
693{
694        struct se_device *dev = cmd->se_dev;
695        int success = scsi_status == GOOD;
696        unsigned long flags;
697
698        cmd->scsi_status = scsi_status;
699
700
701        spin_lock_irqsave(&cmd->t_state_lock, flags);
702        cmd->transport_state &= ~CMD_T_BUSY;
703
704        if (dev && dev->transport->transport_complete) {
705                dev->transport->transport_complete(cmd,
706                                cmd->t_data_sg,
707                                transport_get_sense_buffer(cmd));
708                if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
709                        success = 1;
710        }
711
712        /*
713         * See if we are waiting to complete for an exception condition.
714         */
715        if (cmd->transport_state & CMD_T_REQUEST_STOP) {
716                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
717                complete(&cmd->task_stop_comp);
718                return;
719        }
720
721        /*
722         * Check for case where an explicit ABORT_TASK has been received
723         * and transport_wait_for_tasks() will be waiting for completion..
724         */
725        if (cmd->transport_state & CMD_T_ABORTED ||
726            cmd->transport_state & CMD_T_STOP) {
727                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
728                complete_all(&cmd->t_transport_stop_comp);
729                return;
730        } else if (!success) {
731                INIT_WORK(&cmd->work, target_complete_failure_work);
732        } else {
733                INIT_WORK(&cmd->work, target_complete_ok_work);
734        }
735
736        cmd->t_state = TRANSPORT_COMPLETE;
737        cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
738        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
739
740        queue_work(target_completion_wq, &cmd->work);
741}
742EXPORT_SYMBOL(target_complete_cmd);
743
744void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
745{
746        if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
747                if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
748                        cmd->residual_count += cmd->data_length - length;
749                } else {
750                        cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
751                        cmd->residual_count = cmd->data_length - length;
752                }
753
754                cmd->data_length = length;
755        }
756
757        target_complete_cmd(cmd, scsi_status);
758}
759EXPORT_SYMBOL(target_complete_cmd_with_length);
760
761static void target_add_to_state_list(struct se_cmd *cmd)
762{
763        struct se_device *dev = cmd->se_dev;
764        unsigned long flags;
765
766        spin_lock_irqsave(&dev->execute_task_lock, flags);
767        if (!cmd->state_active) {
768                list_add_tail(&cmd->state_list, &dev->state_list);
769                cmd->state_active = true;
770        }
771        spin_unlock_irqrestore(&dev->execute_task_lock, flags);
772}
773
774/*
775 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
776 */
777static void transport_write_pending_qf(struct se_cmd *cmd);
778static void transport_complete_qf(struct se_cmd *cmd);
779
780void target_qf_do_work(struct work_struct *work)
781{
782        struct se_device *dev = container_of(work, struct se_device,
783                                        qf_work_queue);
784        LIST_HEAD(qf_cmd_list);
785        struct se_cmd *cmd, *cmd_tmp;
786
787        spin_lock_irq(&dev->qf_cmd_lock);
788        list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
789        spin_unlock_irq(&dev->qf_cmd_lock);
790
791        list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
792                list_del(&cmd->se_qf_node);
793                atomic_dec_mb(&dev->dev_qf_count);
794
795                pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
796                        " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
797                        (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
798                        (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
799                        : "UNKNOWN");
800
801                if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
802                        transport_write_pending_qf(cmd);
803                else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
804                        transport_complete_qf(cmd);
805        }
806}
807
808unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
809{
810        switch (cmd->data_direction) {
811        case DMA_NONE:
812                return "NONE";
813        case DMA_FROM_DEVICE:
814                return "READ";
815        case DMA_TO_DEVICE:
816                return "WRITE";
817        case DMA_BIDIRECTIONAL:
818                return "BIDI";
819        default:
820                break;
821        }
822
823        return "UNKNOWN";
824}
825
826void transport_dump_dev_state(
827        struct se_device *dev,
828        char *b,
829        int *bl)
830{
831        *bl += sprintf(b + *bl, "Status: ");
832        if (dev->export_count)
833                *bl += sprintf(b + *bl, "ACTIVATED");
834        else
835                *bl += sprintf(b + *bl, "DEACTIVATED");
836
837        *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
838        *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
839                dev->dev_attrib.block_size,
840                dev->dev_attrib.hw_max_sectors);
841        *bl += sprintf(b + *bl, "        ");
842}
843
844void transport_dump_vpd_proto_id(
845        struct t10_vpd *vpd,
846        unsigned char *p_buf,
847        int p_buf_len)
848{
849        unsigned char buf[VPD_TMP_BUF_SIZE];
850        int len;
851
852        memset(buf, 0, VPD_TMP_BUF_SIZE);
853        len = sprintf(buf, "T10 VPD Protocol Identifier: ");
854
855        switch (vpd->protocol_identifier) {
856        case 0x00:
857                sprintf(buf+len, "Fibre Channel\n");
858                break;
859        case 0x10:
860                sprintf(buf+len, "Parallel SCSI\n");
861                break;
862        case 0x20:
863                sprintf(buf+len, "SSA\n");
864                break;
865        case 0x30:
866                sprintf(buf+len, "IEEE 1394\n");
867                break;
868        case 0x40:
869                sprintf(buf+len, "SCSI Remote Direct Memory Access"
870                                " Protocol\n");
871                break;
872        case 0x50:
873                sprintf(buf+len, "Internet SCSI (iSCSI)\n");
874                break;
875        case 0x60:
876                sprintf(buf+len, "SAS Serial SCSI Protocol\n");
877                break;
878        case 0x70:
879                sprintf(buf+len, "Automation/Drive Interface Transport"
880                                " Protocol\n");
881                break;
882        case 0x80:
883                sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
884                break;
885        default:
886                sprintf(buf+len, "Unknown 0x%02x\n",
887                                vpd->protocol_identifier);
888                break;
889        }
890
891        if (p_buf)
892                strncpy(p_buf, buf, p_buf_len);
893        else
894                pr_debug("%s", buf);
895}
896
897void
898transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
899{
900        /*
901         * Check if the Protocol Identifier Valid (PIV) bit is set..
902         *
903         * from spc3r23.pdf section 7.5.1
904         */
905         if (page_83[1] & 0x80) {
906                vpd->protocol_identifier = (page_83[0] & 0xf0);
907                vpd->protocol_identifier_set = 1;
908                transport_dump_vpd_proto_id(vpd, NULL, 0);
909        }
910}
911EXPORT_SYMBOL(transport_set_vpd_proto_id);
912
913int transport_dump_vpd_assoc(
914        struct t10_vpd *vpd,
915        unsigned char *p_buf,
916        int p_buf_len)
917{
918        unsigned char buf[VPD_TMP_BUF_SIZE];
919        int ret = 0;
920        int len;
921
922        memset(buf, 0, VPD_TMP_BUF_SIZE);
923        len = sprintf(buf, "T10 VPD Identifier Association: ");
924
925        switch (vpd->association) {
926        case 0x00:
927                sprintf(buf+len, "addressed logical unit\n");
928                break;
929        case 0x10:
930                sprintf(buf+len, "target port\n");
931                break;
932        case 0x20:
933                sprintf(buf+len, "SCSI target device\n");
934                break;
935        default:
936                sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
937                ret = -EINVAL;
938                break;
939        }
940
941        if (p_buf)
942                strncpy(p_buf, buf, p_buf_len);
943        else
944                pr_debug("%s", buf);
945
946        return ret;
947}
948
949int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
950{
951        /*
952         * The VPD identification association..
953         *
954         * from spc3r23.pdf Section 7.6.3.1 Table 297
955         */
956        vpd->association = (page_83[1] & 0x30);
957        return transport_dump_vpd_assoc(vpd, NULL, 0);
958}
959EXPORT_SYMBOL(transport_set_vpd_assoc);
960
961int transport_dump_vpd_ident_type(
962        struct t10_vpd *vpd,
963        unsigned char *p_buf,
964        int p_buf_len)
965{
966        unsigned char buf[VPD_TMP_BUF_SIZE];
967        int ret = 0;
968        int len;
969
970        memset(buf, 0, VPD_TMP_BUF_SIZE);
971        len = sprintf(buf, "T10 VPD Identifier Type: ");
972
973        switch (vpd->device_identifier_type) {
974        case 0x00:
975                sprintf(buf+len, "Vendor specific\n");
976                break;
977        case 0x01:
978                sprintf(buf+len, "T10 Vendor ID based\n");
979                break;
980        case 0x02:
981                sprintf(buf+len, "EUI-64 based\n");
982                break;
983        case 0x03:
984                sprintf(buf+len, "NAA\n");
985                break;
986        case 0x04:
987                sprintf(buf+len, "Relative target port identifier\n");
988                break;
989        case 0x08:
990                sprintf(buf+len, "SCSI name string\n");
991                break;
992        default:
993                sprintf(buf+len, "Unsupported: 0x%02x\n",
994                                vpd->device_identifier_type);
995                ret = -EINVAL;
996                break;
997        }
998
999        if (p_buf) {
1000                if (p_buf_len < strlen(buf)+1)
1001                        return -EINVAL;
1002                strncpy(p_buf, buf, p_buf_len);
1003        } else {
1004                pr_debug("%s", buf);
1005        }
1006
1007        return ret;
1008}
1009
1010int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1011{
1012        /*
1013         * The VPD identifier type..
1014         *
1015         * from spc3r23.pdf Section 7.6.3.1 Table 298
1016         */
1017        vpd->device_identifier_type = (page_83[1] & 0x0f);
1018        return transport_dump_vpd_ident_type(vpd, NULL, 0);
1019}
1020EXPORT_SYMBOL(transport_set_vpd_ident_type);
1021
1022int transport_dump_vpd_ident(
1023        struct t10_vpd *vpd,
1024        unsigned char *p_buf,
1025        int p_buf_len)
1026{
1027        unsigned char buf[VPD_TMP_BUF_SIZE];
1028        int ret = 0;
1029
1030        memset(buf, 0, VPD_TMP_BUF_SIZE);
1031
1032        switch (vpd->device_identifier_code_set) {
1033        case 0x01: /* Binary */
1034                snprintf(buf, sizeof(buf),
1035                        "T10 VPD Binary Device Identifier: %s\n",
1036                        &vpd->device_identifier[0]);
1037                break;
1038        case 0x02: /* ASCII */
1039                snprintf(buf, sizeof(buf),
1040                        "T10 VPD ASCII Device Identifier: %s\n",
1041                        &vpd->device_identifier[0]);
1042                break;
1043        case 0x03: /* UTF-8 */
1044                snprintf(buf, sizeof(buf),
1045                        "T10 VPD UTF-8 Device Identifier: %s\n",
1046                        &vpd->device_identifier[0]);
1047                break;
1048        default:
1049                sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1050                        " 0x%02x", vpd->device_identifier_code_set);
1051                ret = -EINVAL;
1052                break;
1053        }
1054
1055        if (p_buf)
1056                strncpy(p_buf, buf, p_buf_len);
1057        else
1058                pr_debug("%s", buf);
1059
1060        return ret;
1061}
1062
1063int
1064transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1065{
1066        static const char hex_str[] = "0123456789abcdef";
1067        int j = 0, i = 4; /* offset to start of the identifier */
1068
1069        /*
1070         * The VPD Code Set (encoding)
1071         *
1072         * from spc3r23.pdf Section 7.6.3.1 Table 296
1073         */
1074        vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1075        switch (vpd->device_identifier_code_set) {
1076        case 0x01: /* Binary */
1077                vpd->device_identifier[j++] =
1078                                hex_str[vpd->device_identifier_type];
1079                while (i < (4 + page_83[3])) {
1080                        vpd->device_identifier[j++] =
1081                                hex_str[(page_83[i] & 0xf0) >> 4];
1082                        vpd->device_identifier[j++] =
1083                                hex_str[page_83[i] & 0x0f];
1084                        i++;
1085                }
1086                break;
1087        case 0x02: /* ASCII */
1088        case 0x03: /* UTF-8 */
1089                while (i < (4 + page_83[3]))
1090                        vpd->device_identifier[j++] = page_83[i++];
1091                break;
1092        default:
1093                break;
1094        }
1095
1096        return transport_dump_vpd_ident(vpd, NULL, 0);
1097}
1098EXPORT_SYMBOL(transport_set_vpd_ident);
1099
1100static sense_reason_t
1101target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1102                               unsigned int size)
1103{
1104        u32 mtl;
1105
1106        if (!cmd->se_tfo->max_data_sg_nents)
1107                return TCM_NO_SENSE;
1108        /*
1109         * Check if fabric enforced maximum SGL entries per I/O descriptor
1110         * exceeds se_cmd->data_length.  If true, set SCF_UNDERFLOW_BIT +
1111         * residual_count and reduce original cmd->data_length to maximum
1112         * length based on single PAGE_SIZE entry scatter-lists.
1113         */
1114        mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1115        if (cmd->data_length > mtl) {
1116                /*
1117                 * If an existing CDB overflow is present, calculate new residual
1118                 * based on CDB size minus fabric maximum transfer length.
1119                 *
1120                 * If an existing CDB underflow is present, calculate new residual
1121                 * based on original cmd->data_length minus fabric maximum transfer
1122                 * length.
1123                 *
1124                 * Otherwise, set the underflow residual based on cmd->data_length
1125                 * minus fabric maximum transfer length.
1126                 */
1127                if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1128                        cmd->residual_count = (size - mtl);
1129                } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1130                        u32 orig_dl = size + cmd->residual_count;
1131                        cmd->residual_count = (orig_dl - mtl);
1132                } else {
1133                        cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1134                        cmd->residual_count = (cmd->data_length - mtl);
1135                }
1136                cmd->data_length = mtl;
1137                /*
1138                 * Reset sbc_check_prot() calculated protection payload
1139                 * length based upon the new smaller MTL.
1140                 */
1141                if (cmd->prot_length) {
1142                        u32 sectors = (mtl / dev->dev_attrib.block_size);
1143                        cmd->prot_length = dev->prot_length * sectors;
1144                }
1145        }
1146        return TCM_NO_SENSE;
1147}
1148
1149sense_reason_t
1150target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1151{
1152        struct se_device *dev = cmd->se_dev;
1153
1154        if (cmd->unknown_data_length) {
1155                cmd->data_length = size;
1156        } else if (size != cmd->data_length) {
1157                pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1158                        " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1159                        " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1160                                cmd->data_length, size, cmd->t_task_cdb[0]);
1161
1162                if (cmd->data_direction == DMA_TO_DEVICE &&
1163                    cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1164                        pr_err("Rejecting underflow/overflow WRITE data\n");
1165                        return TCM_INVALID_CDB_FIELD;
1166                }
1167                /*
1168                 * Reject READ_* or WRITE_* with overflow/underflow for
1169                 * type SCF_SCSI_DATA_CDB.
1170                 */
1171                if (dev->dev_attrib.block_size != 512)  {
1172                        pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1173                                " CDB on non 512-byte sector setup subsystem"
1174                                " plugin: %s\n", dev->transport->name);
1175                        /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1176                        return TCM_INVALID_CDB_FIELD;
1177                }
1178                /*
1179                 * For the overflow case keep the existing fabric provided
1180                 * ->data_length.  Otherwise for the underflow case, reset
1181                 * ->data_length to the smaller SCSI expected data transfer
1182                 * length.
1183                 */
1184                if (size > cmd->data_length) {
1185                        cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1186                        cmd->residual_count = (size - cmd->data_length);
1187                } else {
1188                        cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1189                        cmd->residual_count = (cmd->data_length - size);
1190                        cmd->data_length = size;
1191                }
1192        }
1193
1194        return target_check_max_data_sg_nents(cmd, dev, size);
1195
1196}
1197
1198/*
1199 * Used by fabric modules containing a local struct se_cmd within their
1200 * fabric dependent per I/O descriptor.
1201 *
1202 * Preserves the value of @cmd->tag.
1203 */
1204void transport_init_se_cmd(
1205        struct se_cmd *cmd,
1206        const struct target_core_fabric_ops *tfo,
1207        struct se_session *se_sess,
1208        u32 data_length,
1209        int data_direction,
1210        int task_attr,
1211        unsigned char *sense_buffer)
1212{
1213        INIT_LIST_HEAD(&cmd->se_delayed_node);
1214        INIT_LIST_HEAD(&cmd->se_qf_node);
1215        INIT_LIST_HEAD(&cmd->se_cmd_list);
1216        INIT_LIST_HEAD(&cmd->state_list);
1217        init_completion(&cmd->t_transport_stop_comp);
1218        init_completion(&cmd->cmd_wait_comp);
1219        init_completion(&cmd->task_stop_comp);
1220        spin_lock_init(&cmd->t_state_lock);
1221        kref_init(&cmd->cmd_kref);
1222        cmd->transport_state = CMD_T_DEV_ACTIVE;
1223
1224        cmd->se_tfo = tfo;
1225        cmd->se_sess = se_sess;
1226        cmd->data_length = data_length;
1227        cmd->data_direction = data_direction;
1228        cmd->sam_task_attr = task_attr;
1229        cmd->sense_buffer = sense_buffer;
1230
1231        cmd->state_active = false;
1232}
1233EXPORT_SYMBOL(transport_init_se_cmd);
1234
1235static sense_reason_t
1236transport_check_alloc_task_attr(struct se_cmd *cmd)
1237{
1238        struct se_device *dev = cmd->se_dev;
1239
1240        /*
1241         * Check if SAM Task Attribute emulation is enabled for this
1242         * struct se_device storage object
1243         */
1244        if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1245                return 0;
1246
1247        if (cmd->sam_task_attr == TCM_ACA_TAG) {
1248                pr_debug("SAM Task Attribute ACA"
1249                        " emulation is not supported\n");
1250                return TCM_INVALID_CDB_FIELD;
1251        }
1252
1253        return 0;
1254}
1255
1256sense_reason_t
1257target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1258{
1259        struct se_device *dev = cmd->se_dev;
1260        sense_reason_t ret;
1261
1262        /*
1263         * Ensure that the received CDB is less than the max (252 + 8) bytes
1264         * for VARIABLE_LENGTH_CMD
1265         */
1266        if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1267                pr_err("Received SCSI CDB with command_size: %d that"
1268                        " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1269                        scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1270                return TCM_INVALID_CDB_FIELD;
1271        }
1272        /*
1273         * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1274         * allocate the additional extended CDB buffer now..  Otherwise
1275         * setup the pointer from __t_task_cdb to t_task_cdb.
1276         */
1277        if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1278                cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1279                                                GFP_KERNEL);
1280                if (!cmd->t_task_cdb) {
1281                        pr_err("Unable to allocate cmd->t_task_cdb"
1282                                " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1283                                scsi_command_size(cdb),
1284                                (unsigned long)sizeof(cmd->__t_task_cdb));
1285                        return TCM_OUT_OF_RESOURCES;
1286                }
1287        } else
1288                cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1289        /*
1290         * Copy the original CDB into cmd->
1291         */
1292        memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1293
1294        trace_target_sequencer_start(cmd);
1295
1296        ret = dev->transport->parse_cdb(cmd);
1297        if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1298                pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1299                                    cmd->se_tfo->get_fabric_name(),
1300                                    cmd->se_sess->se_node_acl->initiatorname,
1301                                    cmd->t_task_cdb[0]);
1302        if (ret)
1303                return ret;
1304
1305        ret = transport_check_alloc_task_attr(cmd);
1306        if (ret)
1307                return ret;
1308
1309        cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1310        atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1311        return 0;
1312}
1313EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1314
1315/*
1316 * Used by fabric module frontends to queue tasks directly.
1317 * Many only be used from process context only
1318 */
1319int transport_handle_cdb_direct(
1320        struct se_cmd *cmd)
1321{
1322        sense_reason_t ret;
1323
1324        if (!cmd->se_lun) {
1325                dump_stack();
1326                pr_err("cmd->se_lun is NULL\n");
1327                return -EINVAL;
1328        }
1329        if (in_interrupt()) {
1330                dump_stack();
1331                pr_err("transport_generic_handle_cdb cannot be called"
1332                                " from interrupt context\n");
1333                return -EINVAL;
1334        }
1335        /*
1336         * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1337         * outstanding descriptors are handled correctly during shutdown via
1338         * transport_wait_for_tasks()
1339         *
1340         * Also, we don't take cmd->t_state_lock here as we only expect
1341         * this to be called for initial descriptor submission.
1342         */
1343        cmd->t_state = TRANSPORT_NEW_CMD;
1344        cmd->transport_state |= CMD_T_ACTIVE;
1345
1346        /*
1347         * transport_generic_new_cmd() is already handling QUEUE_FULL,
1348         * so follow TRANSPORT_NEW_CMD processing thread context usage
1349         * and call transport_generic_request_failure() if necessary..
1350         */
1351        ret = transport_generic_new_cmd(cmd);
1352        if (ret)
1353                transport_generic_request_failure(cmd, ret);
1354        return 0;
1355}
1356EXPORT_SYMBOL(transport_handle_cdb_direct);
1357
1358sense_reason_t
1359transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1360                u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1361{
1362        if (!sgl || !sgl_count)
1363                return 0;
1364
1365        /*
1366         * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1367         * scatterlists already have been set to follow what the fabric
1368         * passes for the original expected data transfer length.
1369         */
1370        if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1371                pr_warn("Rejecting SCSI DATA overflow for fabric using"
1372                        " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1373                return TCM_INVALID_CDB_FIELD;
1374        }
1375
1376        cmd->t_data_sg = sgl;
1377        cmd->t_data_nents = sgl_count;
1378        cmd->t_bidi_data_sg = sgl_bidi;
1379        cmd->t_bidi_data_nents = sgl_bidi_count;
1380
1381        cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1382        return 0;
1383}
1384
1385/*
1386 * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1387 *                       se_cmd + use pre-allocated SGL memory.
1388 *
1389 * @se_cmd: command descriptor to submit
1390 * @se_sess: associated se_sess for endpoint
1391 * @cdb: pointer to SCSI CDB
1392 * @sense: pointer to SCSI sense buffer
1393 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1394 * @data_length: fabric expected data transfer length
1395 * @task_addr: SAM task attribute
1396 * @data_dir: DMA data direction
1397 * @flags: flags for command submission from target_sc_flags_tables
1398 * @sgl: struct scatterlist memory for unidirectional mapping
1399 * @sgl_count: scatterlist count for unidirectional mapping
1400 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1401 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1402 * @sgl_prot: struct scatterlist memory protection information
1403 * @sgl_prot_count: scatterlist count for protection information
1404 *
1405 * Task tags are supported if the caller has set @se_cmd->tag.
1406 *
1407 * Returns non zero to signal active I/O shutdown failure.  All other
1408 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1409 * but still return zero here.
1410 *
1411 * This may only be called from process context, and also currently
1412 * assumes internal allocation of fabric payload buffer by target-core.
1413 */
1414int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1415                unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1416                u32 data_length, int task_attr, int data_dir, int flags,
1417                struct scatterlist *sgl, u32 sgl_count,
1418                struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1419                struct scatterlist *sgl_prot, u32 sgl_prot_count)
1420{
1421        struct se_portal_group *se_tpg;
1422        sense_reason_t rc;
1423        int ret;
1424
1425        se_tpg = se_sess->se_tpg;
1426        BUG_ON(!se_tpg);
1427        BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1428        BUG_ON(in_interrupt());
1429        /*
1430         * Initialize se_cmd for target operation.  From this point
1431         * exceptions are handled by sending exception status via
1432         * target_core_fabric_ops->queue_status() callback
1433         */
1434        transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1435                                data_length, data_dir, task_attr, sense);
1436        if (flags & TARGET_SCF_UNKNOWN_SIZE)
1437                se_cmd->unknown_data_length = 1;
1438        /*
1439         * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1440         * se_sess->sess_cmd_list.  A second kref_get here is necessary
1441         * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1442         * kref_put() to happen during fabric packet acknowledgement.
1443         */
1444        ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1445        if (ret)
1446                return ret;
1447        /*
1448         * Signal bidirectional data payloads to target-core
1449         */
1450        if (flags & TARGET_SCF_BIDI_OP)
1451                se_cmd->se_cmd_flags |= SCF_BIDI;
1452        /*
1453         * Locate se_lun pointer and attach it to struct se_cmd
1454         */
1455        rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1456        if (rc) {
1457                transport_send_check_condition_and_sense(se_cmd, rc, 0);
1458                target_put_sess_cmd(se_cmd);
1459                return 0;
1460        }
1461
1462        rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1463        if (rc != 0) {
1464                transport_generic_request_failure(se_cmd, rc);
1465                return 0;
1466        }
1467
1468        /*
1469         * Save pointers for SGLs containing protection information,
1470         * if present.
1471         */
1472        if (sgl_prot_count) {
1473                se_cmd->t_prot_sg = sgl_prot;
1474                se_cmd->t_prot_nents = sgl_prot_count;
1475                se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1476        }
1477
1478        /*
1479         * When a non zero sgl_count has been passed perform SGL passthrough
1480         * mapping for pre-allocated fabric memory instead of having target
1481         * core perform an internal SGL allocation..
1482         */
1483        if (sgl_count != 0) {
1484                BUG_ON(!sgl);
1485
1486                /*
1487                 * A work-around for tcm_loop as some userspace code via
1488                 * scsi-generic do not memset their associated read buffers,
1489                 * so go ahead and do that here for type non-data CDBs.  Also
1490                 * note that this is currently guaranteed to be a single SGL
1491                 * for this case by target core in target_setup_cmd_from_cdb()
1492                 * -> transport_generic_cmd_sequencer().
1493                 */
1494                if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1495                     se_cmd->data_direction == DMA_FROM_DEVICE) {
1496                        unsigned char *buf = NULL;
1497
1498                        if (sgl)
1499                                buf = kmap(sg_page(sgl)) + sgl->offset;
1500
1501                        if (buf) {
1502                                memset(buf, 0, sgl->length);
1503                                kunmap(sg_page(sgl));
1504                        }
1505                }
1506
1507                rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1508                                sgl_bidi, sgl_bidi_count);
1509                if (rc != 0) {
1510                        transport_generic_request_failure(se_cmd, rc);
1511                        return 0;
1512                }
1513        }
1514
1515        /*
1516         * Check if we need to delay processing because of ALUA
1517         * Active/NonOptimized primary access state..
1518         */
1519        core_alua_check_nonop_delay(se_cmd);
1520
1521        transport_handle_cdb_direct(se_cmd);
1522        return 0;
1523}
1524EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1525
1526/*
1527 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1528 *
1529 * @se_cmd: command descriptor to submit
1530 * @se_sess: associated se_sess for endpoint
1531 * @cdb: pointer to SCSI CDB
1532 * @sense: pointer to SCSI sense buffer
1533 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1534 * @data_length: fabric expected data transfer length
1535 * @task_addr: SAM task attribute
1536 * @data_dir: DMA data direction
1537 * @flags: flags for command submission from target_sc_flags_tables
1538 *
1539 * Task tags are supported if the caller has set @se_cmd->tag.
1540 *
1541 * Returns non zero to signal active I/O shutdown failure.  All other
1542 * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1543 * but still return zero here.
1544 *
1545 * This may only be called from process context, and also currently
1546 * assumes internal allocation of fabric payload buffer by target-core.
1547 *
1548 * It also assumes interal target core SGL memory allocation.
1549 */
1550int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1551                unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1552                u32 data_length, int task_attr, int data_dir, int flags)
1553{
1554        return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1555                        unpacked_lun, data_length, task_attr, data_dir,
1556                        flags, NULL, 0, NULL, 0, NULL, 0);
1557}
1558EXPORT_SYMBOL(target_submit_cmd);
1559
1560static void target_complete_tmr_failure(struct work_struct *work)
1561{
1562        struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1563
1564        se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1565        se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1566
1567        transport_cmd_check_stop_to_fabric(se_cmd);
1568}
1569
1570/**
1571 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1572 *                     for TMR CDBs
1573 *
1574 * @se_cmd: command descriptor to submit
1575 * @se_sess: associated se_sess for endpoint
1576 * @sense: pointer to SCSI sense buffer
1577 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1578 * @fabric_context: fabric context for TMR req
1579 * @tm_type: Type of TM request
1580 * @gfp: gfp type for caller
1581 * @tag: referenced task tag for TMR_ABORT_TASK
1582 * @flags: submit cmd flags
1583 *
1584 * Callable from all contexts.
1585 **/
1586
1587int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1588                unsigned char *sense, u64 unpacked_lun,
1589                void *fabric_tmr_ptr, unsigned char tm_type,
1590                gfp_t gfp, unsigned int tag, int flags)
1591{
1592        struct se_portal_group *se_tpg;
1593        int ret;
1594
1595        se_tpg = se_sess->se_tpg;
1596        BUG_ON(!se_tpg);
1597
1598        transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1599                              0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1600        /*
1601         * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1602         * allocation failure.
1603         */
1604        ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1605        if (ret < 0)
1606                return -ENOMEM;
1607
1608        if (tm_type == TMR_ABORT_TASK)
1609                se_cmd->se_tmr_req->ref_task_tag = tag;
1610
1611        /* See target_submit_cmd for commentary */
1612        ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1613        if (ret) {
1614                core_tmr_release_req(se_cmd->se_tmr_req);
1615                return ret;
1616        }
1617
1618        ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1619        if (ret) {
1620                /*
1621                 * For callback during failure handling, push this work off
1622                 * to process context with TMR_LUN_DOES_NOT_EXIST status.
1623                 */
1624                INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1625                schedule_work(&se_cmd->work);
1626                return 0;
1627        }
1628        transport_generic_handle_tmr(se_cmd);
1629        return 0;
1630}
1631EXPORT_SYMBOL(target_submit_tmr);
1632
1633/*
1634 * If the cmd is active, request it to be stopped and sleep until it
1635 * has completed.
1636 */
1637bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1638        __releases(&cmd->t_state_lock)
1639        __acquires(&cmd->t_state_lock)
1640{
1641        bool was_active = false;
1642
1643        if (cmd->transport_state & CMD_T_BUSY) {
1644                cmd->transport_state |= CMD_T_REQUEST_STOP;
1645                spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1646
1647                pr_debug("cmd %p waiting to complete\n", cmd);
1648                wait_for_completion(&cmd->task_stop_comp);
1649                pr_debug("cmd %p stopped successfully\n", cmd);
1650
1651                spin_lock_irqsave(&cmd->t_state_lock, *flags);
1652                cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1653                cmd->transport_state &= ~CMD_T_BUSY;
1654                was_active = true;
1655        }
1656
1657        return was_active;
1658}
1659
1660/*
1661 * Handle SAM-esque emulation for generic transport request failures.
1662 */
1663void transport_generic_request_failure(struct se_cmd *cmd,
1664                sense_reason_t sense_reason)
1665{
1666        int ret = 0, post_ret = 0;
1667
1668        pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08llx"
1669                " CDB: 0x%02x\n", cmd, cmd->tag, cmd->t_task_cdb[0]);
1670        pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1671                cmd->se_tfo->get_cmd_state(cmd),
1672                cmd->t_state, sense_reason);
1673        pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1674                (cmd->transport_state & CMD_T_ACTIVE) != 0,
1675                (cmd->transport_state & CMD_T_STOP) != 0,
1676                (cmd->transport_state & CMD_T_SENT) != 0);
1677
1678        /*
1679         * For SAM Task Attribute emulation for failed struct se_cmd
1680         */
1681        transport_complete_task_attr(cmd);
1682        /*
1683         * Handle special case for COMPARE_AND_WRITE failure, where the
1684         * callback is expected to drop the per device ->caw_sem.
1685         */
1686        if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1687             cmd->transport_complete_callback)
1688                cmd->transport_complete_callback(cmd, false, &post_ret);
1689
1690        switch (sense_reason) {
1691        case TCM_NON_EXISTENT_LUN:
1692        case TCM_UNSUPPORTED_SCSI_OPCODE:
1693        case TCM_INVALID_CDB_FIELD:
1694        case TCM_INVALID_PARAMETER_LIST:
1695        case TCM_PARAMETER_LIST_LENGTH_ERROR:
1696        case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1697        case TCM_UNKNOWN_MODE_PAGE:
1698        case TCM_WRITE_PROTECTED:
1699        case TCM_ADDRESS_OUT_OF_RANGE:
1700        case TCM_CHECK_CONDITION_ABORT_CMD:
1701        case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1702        case TCM_CHECK_CONDITION_NOT_READY:
1703        case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1704        case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1705        case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1706        case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1707                break;
1708        case TCM_OUT_OF_RESOURCES:
1709                sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1710                break;
1711        case TCM_RESERVATION_CONFLICT:
1712                /*
1713                 * No SENSE Data payload for this case, set SCSI Status
1714                 * and queue the response to $FABRIC_MOD.
1715                 *
1716                 * Uses linux/include/scsi/scsi.h SAM status codes defs
1717                 */
1718                cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1719                /*
1720                 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1721                 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1722                 * CONFLICT STATUS.
1723                 *
1724                 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1725                 */
1726                if (cmd->se_sess &&
1727                    cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1728                        target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1729                                               cmd->orig_fe_lun, 0x2C,
1730                                        ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1731                }
1732                trace_target_cmd_complete(cmd);
1733                ret = cmd->se_tfo->queue_status(cmd);
1734                if (ret == -EAGAIN || ret == -ENOMEM)
1735                        goto queue_full;
1736                goto check_stop;
1737        default:
1738                pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1739                        cmd->t_task_cdb[0], sense_reason);
1740                sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1741                break;
1742        }
1743
1744        ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1745        if (ret == -EAGAIN || ret == -ENOMEM)
1746                goto queue_full;
1747
1748check_stop:
1749        transport_lun_remove_cmd(cmd);
1750        transport_cmd_check_stop_to_fabric(cmd);
1751        return;
1752
1753queue_full:
1754        cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1755        transport_handle_queue_full(cmd, cmd->se_dev);
1756}
1757EXPORT_SYMBOL(transport_generic_request_failure);
1758
1759void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1760{
1761        sense_reason_t ret;
1762
1763        if (!cmd->execute_cmd) {
1764                ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1765                goto err;
1766        }
1767        if (do_checks) {
1768                /*
1769                 * Check for an existing UNIT ATTENTION condition after
1770                 * target_handle_task_attr() has done SAM task attr
1771                 * checking, and possibly have already defered execution
1772                 * out to target_restart_delayed_cmds() context.
1773                 */
1774                ret = target_scsi3_ua_check(cmd);
1775                if (ret)
1776                        goto err;
1777
1778                ret = target_alua_state_check(cmd);
1779                if (ret)
1780                        goto err;
1781
1782                ret = target_check_reservation(cmd);
1783                if (ret) {
1784                        cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1785                        goto err;
1786                }
1787        }
1788
1789        ret = cmd->execute_cmd(cmd);
1790        if (!ret)
1791                return;
1792err:
1793        spin_lock_irq(&cmd->t_state_lock);
1794        cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1795        spin_unlock_irq(&cmd->t_state_lock);
1796
1797        transport_generic_request_failure(cmd, ret);
1798}
1799
1800static int target_write_prot_action(struct se_cmd *cmd)
1801{
1802        u32 sectors;
1803        /*
1804         * Perform WRITE_INSERT of PI using software emulation when backend
1805         * device has PI enabled, if the transport has not already generated
1806         * PI using hardware WRITE_INSERT offload.
1807         */
1808        switch (cmd->prot_op) {
1809        case TARGET_PROT_DOUT_INSERT:
1810                if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1811                        sbc_dif_generate(cmd);
1812                break;
1813        case TARGET_PROT_DOUT_STRIP:
1814                if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1815                        break;
1816
1817                sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1818                cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1819                                             sectors, 0, cmd->t_prot_sg, 0);
1820                if (unlikely(cmd->pi_err)) {
1821                        spin_lock_irq(&cmd->t_state_lock);
1822                        cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1823                        spin_unlock_irq(&cmd->t_state_lock);
1824                        transport_generic_request_failure(cmd, cmd->pi_err);
1825                        return -1;
1826                }
1827                break;
1828        default:
1829                break;
1830        }
1831
1832        return 0;
1833}
1834
1835static bool target_handle_task_attr(struct se_cmd *cmd)
1836{
1837        struct se_device *dev = cmd->se_dev;
1838
1839        if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1840                return false;
1841
1842        cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
1843
1844        /*
1845         * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1846         * to allow the passed struct se_cmd list of tasks to the front of the list.
1847         */
1848        switch (cmd->sam_task_attr) {
1849        case TCM_HEAD_TAG:
1850                pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1851                         cmd->t_task_cdb[0]);
1852                return false;
1853        case TCM_ORDERED_TAG:
1854                atomic_inc_mb(&dev->dev_ordered_sync);
1855
1856                pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1857                         cmd->t_task_cdb[0]);
1858
1859                /*
1860                 * Execute an ORDERED command if no other older commands
1861                 * exist that need to be completed first.
1862                 */
1863                if (!atomic_read(&dev->simple_cmds))
1864                        return false;
1865                break;
1866        default:
1867                /*
1868                 * For SIMPLE and UNTAGGED Task Attribute commands
1869                 */
1870                atomic_inc_mb(&dev->simple_cmds);
1871                break;
1872        }
1873
1874        if (atomic_read(&dev->dev_ordered_sync) == 0)
1875                return false;
1876
1877        spin_lock(&dev->delayed_cmd_lock);
1878        list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1879        spin_unlock(&dev->delayed_cmd_lock);
1880
1881        pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
1882                cmd->t_task_cdb[0], cmd->sam_task_attr);
1883        return true;
1884}
1885
1886static int __transport_check_aborted_status(struct se_cmd *, int);
1887
1888void target_execute_cmd(struct se_cmd *cmd)
1889{
1890        /*
1891         * Determine if frontend context caller is requesting the stopping of
1892         * this command for frontend exceptions.
1893         *
1894         * If the received CDB has aleady been aborted stop processing it here.
1895         */
1896        spin_lock_irq(&cmd->t_state_lock);
1897        if (__transport_check_aborted_status(cmd, 1)) {
1898                spin_unlock_irq(&cmd->t_state_lock);
1899                return;
1900        }
1901        if (cmd->transport_state & CMD_T_STOP) {
1902                pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1903                        __func__, __LINE__, cmd->tag);
1904
1905                spin_unlock_irq(&cmd->t_state_lock);
1906                complete_all(&cmd->t_transport_stop_comp);
1907                return;
1908        }
1909
1910        cmd->t_state = TRANSPORT_PROCESSING;
1911        cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1912        spin_unlock_irq(&cmd->t_state_lock);
1913
1914        if (target_write_prot_action(cmd))
1915                return;
1916
1917        if (target_handle_task_attr(cmd)) {
1918                spin_lock_irq(&cmd->t_state_lock);
1919                cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1920                spin_unlock_irq(&cmd->t_state_lock);
1921                return;
1922        }
1923
1924        __target_execute_cmd(cmd, true);
1925}
1926EXPORT_SYMBOL(target_execute_cmd);
1927
1928/*
1929 * Process all commands up to the last received ORDERED task attribute which
1930 * requires another blocking boundary
1931 */
1932static void target_restart_delayed_cmds(struct se_device *dev)
1933{
1934        for (;;) {
1935                struct se_cmd *cmd;
1936
1937                spin_lock(&dev->delayed_cmd_lock);
1938                if (list_empty(&dev->delayed_cmd_list)) {
1939                        spin_unlock(&dev->delayed_cmd_lock);
1940                        break;
1941                }
1942
1943                cmd = list_entry(dev->delayed_cmd_list.next,
1944                                 struct se_cmd, se_delayed_node);
1945                list_del(&cmd->se_delayed_node);
1946                spin_unlock(&dev->delayed_cmd_lock);
1947
1948                __target_execute_cmd(cmd, true);
1949
1950                if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1951                        break;
1952        }
1953}
1954
1955/*
1956 * Called from I/O completion to determine which dormant/delayed
1957 * and ordered cmds need to have their tasks added to the execution queue.
1958 */
1959static void transport_complete_task_attr(struct se_cmd *cmd)
1960{
1961        struct se_device *dev = cmd->se_dev;
1962
1963        if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1964                return;
1965
1966        if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
1967                goto restart;
1968
1969        if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1970                atomic_dec_mb(&dev->simple_cmds);
1971                dev->dev_cur_ordered_id++;
1972                pr_debug("Incremented dev->dev_cur_ordered_id: %u for SIMPLE\n",
1973                         dev->dev_cur_ordered_id);
1974        } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1975                dev->dev_cur_ordered_id++;
1976                pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
1977                         dev->dev_cur_ordered_id);
1978        } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1979                atomic_dec_mb(&dev->dev_ordered_sync);
1980
1981                dev->dev_cur_ordered_id++;
1982                pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
1983                         dev->dev_cur_ordered_id);
1984        }
1985restart:
1986        target_restart_delayed_cmds(dev);
1987}
1988
1989static void transport_complete_qf(struct se_cmd *cmd)
1990{
1991        int ret = 0;
1992
1993        transport_complete_task_attr(cmd);
1994
1995        if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1996                trace_target_cmd_complete(cmd);
1997                ret = cmd->se_tfo->queue_status(cmd);
1998                goto out;
1999        }
2000
2001        switch (cmd->data_direction) {
2002        case DMA_FROM_DEVICE:
2003                trace_target_cmd_complete(cmd);
2004                ret = cmd->se_tfo->queue_data_in(cmd);
2005                break;
2006        case DMA_TO_DEVICE:
2007                if (cmd->se_cmd_flags & SCF_BIDI) {
2008                        ret = cmd->se_tfo->queue_data_in(cmd);
2009                        break;
2010                }
2011                /* Fall through for DMA_TO_DEVICE */
2012        case DMA_NONE:
2013                trace_target_cmd_complete(cmd);
2014                ret = cmd->se_tfo->queue_status(cmd);
2015                break;
2016        default:
2017                break;
2018        }
2019
2020out:
2021        if (ret < 0) {
2022                transport_handle_queue_full(cmd, cmd->se_dev);
2023                return;
2024        }
2025        transport_lun_remove_cmd(cmd);
2026        transport_cmd_check_stop_to_fabric(cmd);
2027}
2028
2029static void transport_handle_queue_full(
2030        struct se_cmd *cmd,
2031        struct se_device *dev)
2032{
2033        spin_lock_irq(&dev->qf_cmd_lock);
2034        list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2035        atomic_inc_mb(&dev->dev_qf_count);
2036        spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2037
2038        schedule_work(&cmd->se_dev->qf_work_queue);
2039}
2040
2041static bool target_read_prot_action(struct se_cmd *cmd)
2042{
2043        switch (cmd->prot_op) {
2044        case TARGET_PROT_DIN_STRIP:
2045                if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2046                        u32 sectors = cmd->data_length >>
2047                                  ilog2(cmd->se_dev->dev_attrib.block_size);
2048
2049                        cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2050                                                     sectors, 0, cmd->t_prot_sg,
2051                                                     0);
2052                        if (cmd->pi_err)
2053                                return true;
2054                }
2055                break;
2056        case TARGET_PROT_DIN_INSERT:
2057                if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2058                        break;
2059
2060                sbc_dif_generate(cmd);
2061                break;
2062        default:
2063                break;
2064        }
2065
2066        return false;
2067}
2068
2069static void target_complete_ok_work(struct work_struct *work)
2070{
2071        struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2072        int ret;
2073
2074        /*
2075         * Check if we need to move delayed/dormant tasks from cmds on the
2076         * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2077         * Attribute.
2078         */
2079        transport_complete_task_attr(cmd);
2080
2081        /*
2082         * Check to schedule QUEUE_FULL work, or execute an existing
2083         * cmd->transport_qf_callback()
2084         */
2085        if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2086                schedule_work(&cmd->se_dev->qf_work_queue);
2087
2088        /*
2089         * Check if we need to send a sense buffer from
2090         * the struct se_cmd in question.
2091         */
2092        if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2093                WARN_ON(!cmd->scsi_status);
2094                ret = transport_send_check_condition_and_sense(
2095                                        cmd, 0, 1);
2096                if (ret == -EAGAIN || ret == -ENOMEM)
2097                        goto queue_full;
2098
2099                transport_lun_remove_cmd(cmd);
2100                transport_cmd_check_stop_to_fabric(cmd);
2101                return;
2102        }
2103        /*
2104         * Check for a callback, used by amongst other things
2105         * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2106         */
2107        if (cmd->transport_complete_callback) {
2108                sense_reason_t rc;
2109                bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2110                bool zero_dl = !(cmd->data_length);
2111                int post_ret = 0;
2112
2113                rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2114                if (!rc && !post_ret) {
2115                        if (caw && zero_dl)
2116                                goto queue_rsp;
2117
2118                        return;
2119                } else if (rc) {
2120                        ret = transport_send_check_condition_and_sense(cmd,
2121                                                rc, 0);
2122                        if (ret == -EAGAIN || ret == -ENOMEM)
2123                                goto queue_full;
2124
2125                        transport_lun_remove_cmd(cmd);
2126                        transport_cmd_check_stop_to_fabric(cmd);
2127                        return;
2128                }
2129        }
2130
2131queue_rsp:
2132        switch (cmd->data_direction) {
2133        case DMA_FROM_DEVICE:
2134                atomic_long_add(cmd->data_length,
2135                                &cmd->se_lun->lun_stats.tx_data_octets);
2136                /*
2137                 * Perform READ_STRIP of PI using software emulation when
2138                 * backend had PI enabled, if the transport will not be
2139                 * performing hardware READ_STRIP offload.
2140                 */
2141                if (target_read_prot_action(cmd)) {
2142                        ret = transport_send_check_condition_and_sense(cmd,
2143                                                cmd->pi_err, 0);
2144                        if (ret == -EAGAIN || ret == -ENOMEM)
2145                                goto queue_full;
2146
2147                        transport_lun_remove_cmd(cmd);
2148                        transport_cmd_check_stop_to_fabric(cmd);
2149                        return;
2150                }
2151
2152                trace_target_cmd_complete(cmd);
2153                ret = cmd->se_tfo->queue_data_in(cmd);
2154                if (ret == -EAGAIN || ret == -ENOMEM)
2155                        goto queue_full;
2156                break;
2157        case DMA_TO_DEVICE:
2158                atomic_long_add(cmd->data_length,
2159                                &cmd->se_lun->lun_stats.rx_data_octets);
2160                /*
2161                 * Check if we need to send READ payload for BIDI-COMMAND
2162                 */
2163                if (cmd->se_cmd_flags & SCF_BIDI) {
2164                        atomic_long_add(cmd->data_length,
2165                                        &cmd->se_lun->lun_stats.tx_data_octets);
2166                        ret = cmd->se_tfo->queue_data_in(cmd);
2167                        if (ret == -EAGAIN || ret == -ENOMEM)
2168                                goto queue_full;
2169                        break;
2170                }
2171                /* Fall through for DMA_TO_DEVICE */
2172        case DMA_NONE:
2173                trace_target_cmd_complete(cmd);
2174                ret = cmd->se_tfo->queue_status(cmd);
2175                if (ret == -EAGAIN || ret == -ENOMEM)
2176                        goto queue_full;
2177                break;
2178        default:
2179                break;
2180        }
2181
2182        transport_lun_remove_cmd(cmd);
2183        transport_cmd_check_stop_to_fabric(cmd);
2184        return;
2185
2186queue_full:
2187        pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2188                " data_direction: %d\n", cmd, cmd->data_direction);
2189        cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2190        transport_handle_queue_full(cmd, cmd->se_dev);
2191}
2192
2193static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2194{
2195        struct scatterlist *sg;
2196        int count;
2197
2198        for_each_sg(sgl, sg, nents, count)
2199                __free_page(sg_page(sg));
2200
2201        kfree(sgl);
2202}
2203
2204static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2205{
2206        /*
2207         * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2208         * emulation, and free + reset pointers if necessary..
2209         */
2210        if (!cmd->t_data_sg_orig)
2211                return;
2212
2213        kfree(cmd->t_data_sg);
2214        cmd->t_data_sg = cmd->t_data_sg_orig;
2215        cmd->t_data_sg_orig = NULL;
2216        cmd->t_data_nents = cmd->t_data_nents_orig;
2217        cmd->t_data_nents_orig = 0;
2218}
2219
2220static inline void transport_free_pages(struct se_cmd *cmd)
2221{
2222        if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2223                transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2224                cmd->t_prot_sg = NULL;
2225                cmd->t_prot_nents = 0;
2226        }
2227
2228        if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2229                /*
2230                 * Release special case READ buffer payload required for
2231                 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2232                 */
2233                if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2234                        transport_free_sgl(cmd->t_bidi_data_sg,
2235                                           cmd->t_bidi_data_nents);
2236                        cmd->t_bidi_data_sg = NULL;
2237                        cmd->t_bidi_data_nents = 0;
2238                }
2239                transport_reset_sgl_orig(cmd);
2240                return;
2241        }
2242        transport_reset_sgl_orig(cmd);
2243
2244        transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2245        cmd->t_data_sg = NULL;
2246        cmd->t_data_nents = 0;
2247
2248        transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2249        cmd->t_bidi_data_sg = NULL;
2250        cmd->t_bidi_data_nents = 0;
2251}
2252
2253/**
2254 * transport_put_cmd - release a reference to a command
2255 * @cmd:       command to release
2256 *
2257 * This routine releases our reference to the command and frees it if possible.
2258 */
2259static int transport_put_cmd(struct se_cmd *cmd)
2260{
2261        BUG_ON(!cmd->se_tfo);
2262        /*
2263         * If this cmd has been setup with target_get_sess_cmd(), drop
2264         * the kref and call ->release_cmd() in kref callback.
2265         */
2266        return target_put_sess_cmd(cmd);
2267}
2268
2269void *transport_kmap_data_sg(struct se_cmd *cmd)
2270{
2271        struct scatterlist *sg = cmd->t_data_sg;
2272        struct page **pages;
2273        int i;
2274
2275        /*
2276         * We need to take into account a possible offset here for fabrics like
2277         * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2278         * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2279         */
2280        if (!cmd->t_data_nents)
2281                return NULL;
2282
2283        BUG_ON(!sg);
2284        if (cmd->t_data_nents == 1)
2285                return kmap(sg_page(sg)) + sg->offset;
2286
2287        /* >1 page. use vmap */
2288        pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2289        if (!pages)
2290                return NULL;
2291
2292        /* convert sg[] to pages[] */
2293        for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2294                pages[i] = sg_page(sg);
2295        }
2296
2297        cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2298        kfree(pages);
2299        if (!cmd->t_data_vmap)
2300                return NULL;
2301
2302        return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2303}
2304EXPORT_SYMBOL(transport_kmap_data_sg);
2305
2306void transport_kunmap_data_sg(struct se_cmd *cmd)
2307{
2308        if (!cmd->t_data_nents) {
2309                return;
2310        } else if (cmd->t_data_nents == 1) {
2311                kunmap(sg_page(cmd->t_data_sg));
2312                return;
2313        }
2314
2315        vunmap(cmd->t_data_vmap);
2316        cmd->t_data_vmap = NULL;
2317}
2318EXPORT_SYMBOL(transport_kunmap_data_sg);
2319
2320int
2321target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2322                 bool zero_page)
2323{
2324        struct scatterlist *sg;
2325        struct page *page;
2326        gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2327        unsigned int nent;
2328        int i = 0;
2329
2330        nent = DIV_ROUND_UP(length, PAGE_SIZE);
2331        sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2332        if (!sg)
2333                return -ENOMEM;
2334
2335        sg_init_table(sg, nent);
2336
2337        while (length) {
2338                u32 page_len = min_t(u32, length, PAGE_SIZE);
2339                page = alloc_page(GFP_KERNEL | zero_flag);
2340                if (!page)
2341                        goto out;
2342
2343                sg_set_page(&sg[i], page, page_len, 0);
2344                length -= page_len;
2345                i++;
2346        }
2347        *sgl = sg;
2348        *nents = nent;
2349        return 0;
2350
2351out:
2352        while (i > 0) {
2353                i--;
2354                __free_page(sg_page(&sg[i]));
2355        }
2356        kfree(sg);
2357        return -ENOMEM;
2358}
2359
2360/*
2361 * Allocate any required resources to execute the command.  For writes we
2362 * might not have the payload yet, so notify the fabric via a call to
2363 * ->write_pending instead. Otherwise place it on the execution queue.
2364 */
2365sense_reason_t
2366transport_generic_new_cmd(struct se_cmd *cmd)
2367{
2368        int ret = 0;
2369        bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2370
2371        if (cmd->prot_op != TARGET_PROT_NORMAL &&
2372            !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2373                ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2374                                       cmd->prot_length, true);
2375                if (ret < 0)
2376                        return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2377        }
2378
2379        /*
2380         * Determine is the TCM fabric module has already allocated physical
2381         * memory, and is directly calling transport_generic_map_mem_to_cmd()
2382         * beforehand.
2383         */
2384        if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2385            cmd->data_length) {
2386
2387                if ((cmd->se_cmd_flags & SCF_BIDI) ||
2388                    (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2389                        u32 bidi_length;
2390
2391                        if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2392                                bidi_length = cmd->t_task_nolb *
2393                                              cmd->se_dev->dev_attrib.block_size;
2394                        else
2395                                bidi_length = cmd->data_length;
2396
2397                        ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2398                                               &cmd->t_bidi_data_nents,
2399                                               bidi_length, zero_flag);
2400                        if (ret < 0)
2401                                return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2402                }
2403
2404                ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2405                                       cmd->data_length, zero_flag);
2406                if (ret < 0)
2407                        return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2408        } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2409                    cmd->data_length) {
2410                /*
2411                 * Special case for COMPARE_AND_WRITE with fabrics
2412                 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2413                 */
2414                u32 caw_length = cmd->t_task_nolb *
2415                                 cmd->se_dev->dev_attrib.block_size;
2416
2417                ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2418                                       &cmd->t_bidi_data_nents,
2419                                       caw_length, zero_flag);
2420                if (ret < 0)
2421                        return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2422        }
2423        /*
2424         * If this command is not a write we can execute it right here,
2425         * for write buffers we need to notify the fabric driver first
2426         * and let it call back once the write buffers are ready.
2427         */
2428        target_add_to_state_list(cmd);
2429        if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2430                target_execute_cmd(cmd);
2431                return 0;
2432        }
2433        transport_cmd_check_stop(cmd, false, true);
2434
2435        ret = cmd->se_tfo->write_pending(cmd);
2436        if (ret == -EAGAIN || ret == -ENOMEM)
2437                goto queue_full;
2438
2439        /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2440        WARN_ON(ret);
2441
2442        return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2443
2444queue_full:
2445        pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2446        cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2447        transport_handle_queue_full(cmd, cmd->se_dev);
2448        return 0;
2449}
2450EXPORT_SYMBOL(transport_generic_new_cmd);
2451
2452static void transport_write_pending_qf(struct se_cmd *cmd)
2453{
2454        int ret;
2455
2456        ret = cmd->se_tfo->write_pending(cmd);
2457        if (ret == -EAGAIN || ret == -ENOMEM) {
2458                pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2459                         cmd);
2460                transport_handle_queue_full(cmd, cmd->se_dev);
2461        }
2462}
2463
2464static bool
2465__transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2466                           unsigned long *flags);
2467
2468static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2469{
2470        unsigned long flags;
2471
2472        spin_lock_irqsave(&cmd->t_state_lock, flags);
2473        __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2474        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2475}
2476
2477int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2478{
2479        int ret = 0;
2480        bool aborted = false, tas = false;
2481
2482        if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2483                if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2484                        target_wait_free_cmd(cmd, &aborted, &tas);
2485
2486                if (!aborted || tas)
2487                        ret = transport_put_cmd(cmd);
2488        } else {
2489                if (wait_for_tasks)
2490                        target_wait_free_cmd(cmd, &aborted, &tas);
2491                /*
2492                 * Handle WRITE failure case where transport_generic_new_cmd()
2493                 * has already added se_cmd to state_list, but fabric has
2494                 * failed command before I/O submission.
2495                 */
2496                if (cmd->state_active)
2497                        target_remove_from_state_list(cmd);
2498
2499                if (cmd->se_lun)
2500                        transport_lun_remove_cmd(cmd);
2501
2502                if (!aborted || tas)
2503                        ret = transport_put_cmd(cmd);
2504        }
2505        /*
2506         * If the task has been internally aborted due to TMR ABORT_TASK
2507         * or LUN_RESET, target_core_tmr.c is responsible for performing
2508         * the remaining calls to target_put_sess_cmd(), and not the
2509         * callers of this function.
2510         */
2511        if (aborted) {
2512                pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2513                wait_for_completion(&cmd->cmd_wait_comp);
2514                cmd->se_tfo->release_cmd(cmd);
2515                ret = 1;
2516        }
2517        return ret;
2518}
2519EXPORT_SYMBOL(transport_generic_free_cmd);
2520
2521/* target_get_sess_cmd - Add command to active ->sess_cmd_list
2522 * @se_cmd:     command descriptor to add
2523 * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2524 */
2525int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2526{
2527        struct se_session *se_sess = se_cmd->se_sess;
2528        unsigned long flags;
2529        int ret = 0;
2530
2531        /*
2532         * Add a second kref if the fabric caller is expecting to handle
2533         * fabric acknowledgement that requires two target_put_sess_cmd()
2534         * invocations before se_cmd descriptor release.
2535         */
2536        if (ack_kref) {
2537                kref_get(&se_cmd->cmd_kref);
2538                se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2539        }
2540
2541        spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2542        if (se_sess->sess_tearing_down) {
2543                ret = -ESHUTDOWN;
2544                goto out;
2545        }
2546        list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2547out:
2548        spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2549
2550        if (ret && ack_kref)
2551                target_put_sess_cmd(se_cmd);
2552
2553        return ret;
2554}
2555EXPORT_SYMBOL(target_get_sess_cmd);
2556
2557static void target_free_cmd_mem(struct se_cmd *cmd)
2558{
2559        transport_free_pages(cmd);
2560
2561        if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2562                core_tmr_release_req(cmd->se_tmr_req);
2563        if (cmd->t_task_cdb != cmd->__t_task_cdb)
2564                kfree(cmd->t_task_cdb);
2565}
2566
2567static void target_release_cmd_kref(struct kref *kref)
2568{
2569        struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2570        struct se_session *se_sess = se_cmd->se_sess;
2571        unsigned long flags;
2572        bool fabric_stop;
2573
2574        spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2575
2576        spin_lock(&se_cmd->t_state_lock);
2577        fabric_stop = (se_cmd->transport_state & CMD_T_FABRIC_STOP) &&
2578                      (se_cmd->transport_state & CMD_T_ABORTED);
2579        spin_unlock(&se_cmd->t_state_lock);
2580
2581        if (se_cmd->cmd_wait_set || fabric_stop) {
2582                list_del_init(&se_cmd->se_cmd_list);
2583                spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2584                target_free_cmd_mem(se_cmd);
2585                complete(&se_cmd->cmd_wait_comp);
2586                return;
2587        }
2588        list_del_init(&se_cmd->se_cmd_list);
2589        spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2590
2591        target_free_cmd_mem(se_cmd);
2592        se_cmd->se_tfo->release_cmd(se_cmd);
2593}
2594
2595/* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2596 * @se_cmd:     command descriptor to drop
2597 */
2598int target_put_sess_cmd(struct se_cmd *se_cmd)
2599{
2600        struct se_session *se_sess = se_cmd->se_sess;
2601
2602        if (!se_sess) {
2603                target_free_cmd_mem(se_cmd);
2604                se_cmd->se_tfo->release_cmd(se_cmd);
2605                return 1;
2606        }
2607        return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2608}
2609EXPORT_SYMBOL(target_put_sess_cmd);
2610
2611/* target_sess_cmd_list_set_waiting - Flag all commands in
2612 *         sess_cmd_list to complete cmd_wait_comp.  Set
2613 *         sess_tearing_down so no more commands are queued.
2614 * @se_sess:    session to flag
2615 */
2616void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2617{
2618        struct se_cmd *se_cmd;
2619        unsigned long flags;
2620        int rc;
2621
2622        spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2623        if (se_sess->sess_tearing_down) {
2624                spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2625                return;
2626        }
2627        se_sess->sess_tearing_down = 1;
2628        list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2629
2630        list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list) {
2631                rc = kref_get_unless_zero(&se_cmd->cmd_kref);
2632                if (rc) {
2633                        se_cmd->cmd_wait_set = 1;
2634                        spin_lock(&se_cmd->t_state_lock);
2635                        se_cmd->transport_state |= CMD_T_FABRIC_STOP;
2636                        spin_unlock(&se_cmd->t_state_lock);
2637                }
2638        }
2639
2640        spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2641}
2642EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2643
2644/* target_wait_for_sess_cmds - Wait for outstanding descriptors
2645 * @se_sess:    session to wait for active I/O
2646 */
2647void target_wait_for_sess_cmds(struct se_session *se_sess)
2648{
2649        struct se_cmd *se_cmd, *tmp_cmd;
2650        unsigned long flags;
2651        bool tas;
2652
2653        list_for_each_entry_safe(se_cmd, tmp_cmd,
2654                                &se_sess->sess_wait_list, se_cmd_list) {
2655                pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2656                        " %d\n", se_cmd, se_cmd->t_state,
2657                        se_cmd->se_tfo->get_cmd_state(se_cmd));
2658
2659                spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2660                tas = (se_cmd->transport_state & CMD_T_TAS);
2661                spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2662
2663                if (!target_put_sess_cmd(se_cmd)) {
2664                        if (tas)
2665                                target_put_sess_cmd(se_cmd);
2666                }
2667
2668                wait_for_completion(&se_cmd->cmd_wait_comp);
2669                pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2670                        " fabric state: %d\n", se_cmd, se_cmd->t_state,
2671                        se_cmd->se_tfo->get_cmd_state(se_cmd));
2672
2673                se_cmd->se_tfo->release_cmd(se_cmd);
2674        }
2675
2676        spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2677        WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2678        spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2679
2680}
2681EXPORT_SYMBOL(target_wait_for_sess_cmds);
2682
2683static void target_lun_confirm(struct percpu_ref *ref)
2684{
2685        struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
2686
2687        complete(&lun->lun_ref_comp);
2688}
2689
2690void transport_clear_lun_ref(struct se_lun *lun)
2691{
2692        /*
2693         * Mark the percpu-ref as DEAD, switch to atomic_t mode, drop
2694         * the initial reference and schedule confirm kill to be
2695         * executed after one full RCU grace period has completed.
2696         */
2697        percpu_ref_kill_and_confirm(&lun->lun_ref, target_lun_confirm);
2698        /*
2699         * The first completion waits for percpu_ref_switch_to_atomic_rcu()
2700         * to call target_lun_confirm after lun->lun_ref has been marked
2701         * as __PERCPU_REF_DEAD on all CPUs, and switches to atomic_t
2702         * mode so that percpu_ref_tryget_live() lookup of lun->lun_ref
2703         * fails for all new incoming I/O.
2704         */
2705        wait_for_completion(&lun->lun_ref_comp);
2706        /*
2707         * The second completion waits for percpu_ref_put_many() to
2708         * invoke ->release() after lun->lun_ref has switched to
2709         * atomic_t mode, and lun->lun_ref.count has reached zero.
2710         *
2711         * At this point all target-core lun->lun_ref references have
2712         * been dropped via transport_lun_remove_cmd(), and it's safe
2713         * to proceed with the remaining LUN shutdown.
2714         */
2715        wait_for_completion(&lun->lun_shutdown_comp);
2716}
2717
2718static bool
2719__transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2720                           bool *aborted, bool *tas, unsigned long *flags)
2721        __releases(&cmd->t_state_lock)
2722        __acquires(&cmd->t_state_lock)
2723{
2724
2725        assert_spin_locked(&cmd->t_state_lock);
2726        WARN_ON_ONCE(!irqs_disabled());
2727
2728        if (fabric_stop)
2729                cmd->transport_state |= CMD_T_FABRIC_STOP;
2730
2731        if (cmd->transport_state & CMD_T_ABORTED)
2732                *aborted = true;
2733
2734        if (cmd->transport_state & CMD_T_TAS)
2735                *tas = true;
2736
2737        if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2738            !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2739                return false;
2740
2741        if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2742            !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2743                return false;
2744
2745        if (!(cmd->transport_state & CMD_T_ACTIVE))
2746                return false;
2747
2748        if (fabric_stop && *aborted)
2749                return false;
2750
2751        cmd->transport_state |= CMD_T_STOP;
2752
2753        pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08llx i_state: %d,"
2754                 " t_state: %d, CMD_T_STOP\n", cmd, cmd->tag,
2755                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2756
2757        spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2758
2759        wait_for_completion(&cmd->t_transport_stop_comp);
2760
2761        spin_lock_irqsave(&cmd->t_state_lock, *flags);
2762        cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2763
2764        pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
2765                 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
2766
2767        return true;
2768}
2769
2770/**
2771 * transport_wait_for_tasks - wait for completion to occur
2772 * @cmd:        command to wait
2773 *
2774 * Called from frontend fabric context to wait for storage engine
2775 * to pause and/or release frontend generated struct se_cmd.
2776 */
2777bool transport_wait_for_tasks(struct se_cmd *cmd)
2778{
2779        unsigned long flags;
2780        bool ret, aborted = false, tas = false;
2781
2782        spin_lock_irqsave(&cmd->t_state_lock, flags);
2783        ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
2784        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2785
2786        return ret;
2787}
2788EXPORT_SYMBOL(transport_wait_for_tasks);
2789
2790struct sense_info {
2791        u8 key;
2792        u8 asc;
2793        u8 ascq;
2794        bool add_sector_info;
2795};
2796
2797static const struct sense_info sense_info_table[] = {
2798        [TCM_NO_SENSE] = {
2799                .key = NOT_READY
2800        },
2801        [TCM_NON_EXISTENT_LUN] = {
2802                .key = ILLEGAL_REQUEST,
2803                .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
2804        },
2805        [TCM_UNSUPPORTED_SCSI_OPCODE] = {
2806                .key = ILLEGAL_REQUEST,
2807                .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2808        },
2809        [TCM_SECTOR_COUNT_TOO_MANY] = {
2810                .key = ILLEGAL_REQUEST,
2811                .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2812        },
2813        [TCM_UNKNOWN_MODE_PAGE] = {
2814                .key = ILLEGAL_REQUEST,
2815                .asc = 0x24, /* INVALID FIELD IN CDB */
2816        },
2817        [TCM_CHECK_CONDITION_ABORT_CMD] = {
2818                .key = ABORTED_COMMAND,
2819                .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
2820                .ascq = 0x03,
2821        },
2822        [TCM_INCORRECT_AMOUNT_OF_DATA] = {
2823                .key = ABORTED_COMMAND,
2824                .asc = 0x0c, /* WRITE ERROR */
2825                .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
2826        },
2827        [TCM_INVALID_CDB_FIELD] = {
2828                .key = ILLEGAL_REQUEST,
2829                .asc = 0x24, /* INVALID FIELD IN CDB */
2830        },
2831        [TCM_INVALID_PARAMETER_LIST] = {
2832                .key = ILLEGAL_REQUEST,
2833                .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
2834        },
2835        [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
2836                .key = ILLEGAL_REQUEST,
2837                .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
2838        },
2839        [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
2840                .key = ILLEGAL_REQUEST,
2841                .asc = 0x0c, /* WRITE ERROR */
2842                .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
2843        },
2844        [TCM_SERVICE_CRC_ERROR] = {
2845                .key = ABORTED_COMMAND,
2846                .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
2847                .ascq = 0x05, /* N/A */
2848        },
2849        [TCM_SNACK_REJECTED] = {
2850                .key = ABORTED_COMMAND,
2851                .asc = 0x11, /* READ ERROR */
2852                .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
2853        },
2854        [TCM_WRITE_PROTECTED] = {
2855                .key = DATA_PROTECT,
2856                .asc = 0x27, /* WRITE PROTECTED */
2857        },
2858        [TCM_ADDRESS_OUT_OF_RANGE] = {
2859                .key = ILLEGAL_REQUEST,
2860                .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2861        },
2862        [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
2863                .key = UNIT_ATTENTION,
2864        },
2865        [TCM_CHECK_CONDITION_NOT_READY] = {
2866                .key = NOT_READY,
2867        },
2868        [TCM_MISCOMPARE_VERIFY] = {
2869                .key = MISCOMPARE,
2870                .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
2871                .ascq = 0x00,
2872        },
2873        [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
2874                .key = ABORTED_COMMAND,
2875                .asc = 0x10,
2876                .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
2877                .add_sector_info = true,
2878        },
2879        [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
2880                .key = ABORTED_COMMAND,
2881                .asc = 0x10,
2882                .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2883                .add_sector_info = true,
2884        },
2885        [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
2886                .key = ABORTED_COMMAND,
2887                .asc = 0x10,
2888                .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2889                .add_sector_info = true,
2890        },
2891        [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
2892                .key = COPY_ABORTED,
2893                .asc = 0x0d,
2894                .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
2895
2896        },
2897        [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
2898                /*
2899                 * Returning ILLEGAL REQUEST would cause immediate IO errors on
2900                 * Solaris initiators.  Returning NOT READY instead means the
2901                 * operations will be retried a finite number of times and we
2902                 * can survive intermittent errors.
2903                 */
2904                .key = NOT_READY,
2905                .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
2906        },
2907};
2908
2909static int translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
2910{
2911        const struct sense_info *si;
2912        u8 *buffer = cmd->sense_buffer;
2913        int r = (__force int)reason;
2914        u8 asc, ascq;
2915        bool desc_format = target_sense_desc_format(cmd->se_dev);
2916
2917        if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
2918                si = &sense_info_table[r];
2919        else
2920                si = &sense_info_table[(__force int)
2921                                       TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
2922
2923        if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
2924                core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2925                WARN_ON_ONCE(asc == 0);
2926        } else if (si->asc == 0) {
2927                WARN_ON_ONCE(cmd->scsi_asc == 0);
2928                asc = cmd->scsi_asc;
2929                ascq = cmd->scsi_ascq;
2930        } else {
2931                asc = si->asc;
2932                ascq = si->ascq;
2933        }
2934
2935        scsi_build_sense_buffer(desc_format, buffer, si->key, asc, ascq);
2936        if (si->add_sector_info)
2937                return scsi_set_sense_information(buffer,
2938                                                  cmd->scsi_sense_length,
2939                                                  cmd->bad_sector);
2940
2941        return 0;
2942}
2943
2944int
2945transport_send_check_condition_and_sense(struct se_cmd *cmd,
2946                sense_reason_t reason, int from_transport)
2947{
2948        unsigned long flags;
2949
2950        spin_lock_irqsave(&cmd->t_state_lock, flags);
2951        if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2952                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2953                return 0;
2954        }
2955        cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2956        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2957
2958        if (!from_transport) {
2959                int rc;
2960
2961                cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2962                cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2963                cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2964                rc = translate_sense_reason(cmd, reason);
2965                if (rc)
2966                        return rc;
2967        }
2968
2969        trace_target_cmd_complete(cmd);
2970        return cmd->se_tfo->queue_status(cmd);
2971}
2972EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2973
2974static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2975        __releases(&cmd->t_state_lock)
2976        __acquires(&cmd->t_state_lock)
2977{
2978        assert_spin_locked(&cmd->t_state_lock);
2979        WARN_ON_ONCE(!irqs_disabled());
2980
2981        if (!(cmd->transport_state & CMD_T_ABORTED))
2982                return 0;
2983        /*
2984         * If cmd has been aborted but either no status is to be sent or it has
2985         * already been sent, just return
2986         */
2987        if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
2988                if (send_status)
2989                        cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2990                return 1;
2991        }
2992
2993        pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
2994                " 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);
2995
2996        cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2997        cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2998        trace_target_cmd_complete(cmd);
2999
3000        spin_unlock_irq(&cmd->t_state_lock);
3001        cmd->se_tfo->queue_status(cmd);
3002        spin_lock_irq(&cmd->t_state_lock);
3003
3004        return 1;
3005}
3006
3007int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
3008{
3009        int ret;
3010
3011        spin_lock_irq(&cmd->t_state_lock);
3012        ret = __transport_check_aborted_status(cmd, send_status);
3013        spin_unlock_irq(&cmd->t_state_lock);
3014
3015        return ret;
3016}
3017EXPORT_SYMBOL(transport_check_aborted_status);
3018
3019void transport_send_task_abort(struct se_cmd *cmd)
3020{
3021        unsigned long flags;
3022
3023        spin_lock_irqsave(&cmd->t_state_lock, flags);
3024        if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
3025                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3026                return;
3027        }
3028        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3029
3030        /*
3031         * If there are still expected incoming fabric WRITEs, we wait
3032         * until until they have completed before sending a TASK_ABORTED
3033         * response.  This response with TASK_ABORTED status will be
3034         * queued back to fabric module by transport_check_aborted_status().
3035         */
3036        if (cmd->data_direction == DMA_TO_DEVICE) {
3037                if (cmd->se_tfo->write_pending_status(cmd) != 0) {
3038                        spin_lock_irqsave(&cmd->t_state_lock, flags);
3039                        if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) {
3040                                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3041                                goto send_abort;
3042                        }
3043                        cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3044                        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3045                        return;
3046                }
3047        }
3048send_abort:
3049        cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3050
3051        transport_lun_remove_cmd(cmd);
3052
3053        pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
3054                 cmd->t_task_cdb[0], cmd->tag);
3055
3056        trace_target_cmd_complete(cmd);
3057        cmd->se_tfo->queue_status(cmd);
3058}
3059
3060static void target_tmr_work(struct work_struct *work)
3061{
3062        struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3063        struct se_device *dev = cmd->se_dev;
3064        struct se_tmr_req *tmr = cmd->se_tmr_req;
3065        unsigned long flags;
3066        int ret;
3067
3068        spin_lock_irqsave(&cmd->t_state_lock, flags);
3069        if (cmd->transport_state & CMD_T_ABORTED) {
3070                tmr->response = TMR_FUNCTION_REJECTED;
3071                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3072                goto check_stop;
3073        }
3074        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3075
3076        switch (tmr->function) {
3077        case TMR_ABORT_TASK:
3078                core_tmr_abort_task(dev, tmr, cmd->se_sess);
3079                break;
3080        case TMR_ABORT_TASK_SET:
3081        case TMR_CLEAR_ACA:
3082        case TMR_CLEAR_TASK_SET:
3083                tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3084                break;
3085        case TMR_LUN_RESET:
3086                ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3087                tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3088                                         TMR_FUNCTION_REJECTED;
3089                if (tmr->response == TMR_FUNCTION_COMPLETE) {
3090                        target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3091                                               cmd->orig_fe_lun, 0x29,
3092                                               ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3093                }
3094                break;
3095        case TMR_TARGET_WARM_RESET:
3096                tmr->response = TMR_FUNCTION_REJECTED;
3097                break;
3098        case TMR_TARGET_COLD_RESET:
3099                tmr->response = TMR_FUNCTION_REJECTED;
3100                break;
3101        default:
3102                pr_err("Uknown TMR function: 0x%02x.\n",
3103                                tmr->function);
3104                tmr->response = TMR_FUNCTION_REJECTED;
3105                break;
3106        }
3107
3108        spin_lock_irqsave(&cmd->t_state_lock, flags);
3109        if (cmd->transport_state & CMD_T_ABORTED) {
3110                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3111                goto check_stop;
3112        }
3113        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3114
3115        cmd->se_tfo->queue_tm_rsp(cmd);
3116
3117check_stop:
3118        transport_cmd_check_stop_to_fabric(cmd);
3119}
3120
3121int transport_generic_handle_tmr(
3122        struct se_cmd *cmd)
3123{
3124        unsigned long flags;
3125        bool aborted = false;
3126
3127        spin_lock_irqsave(&cmd->t_state_lock, flags);
3128        if (cmd->transport_state & CMD_T_ABORTED) {
3129                aborted = true;
3130        } else {
3131                cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3132                cmd->transport_state |= CMD_T_ACTIVE;
3133        }
3134        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3135
3136        if (aborted) {
3137                pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d"
3138                        "ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function,
3139                        cmd->se_tmr_req->ref_task_tag, cmd->tag);
3140                transport_cmd_check_stop_to_fabric(cmd);
3141                return 0;
3142        }
3143
3144        INIT_WORK(&cmd->work, target_tmr_work);
3145        queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3146        return 0;
3147}
3148EXPORT_SYMBOL(transport_generic_handle_tmr);
3149
3150bool
3151target_check_wce(struct se_device *dev)
3152{
3153        bool wce = false;
3154
3155        if (dev->transport->get_write_cache)
3156                wce = dev->transport->get_write_cache(dev);
3157        else if (dev->dev_attrib.emulate_write_cache > 0)
3158                wce = true;
3159
3160        return wce;
3161}
3162
3163bool
3164target_check_fua(struct se_device *dev)
3165{
3166        return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3167}
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