drivers/target/target_core_transport.c

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