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 2002-2012 RisingTide Systems LLC.
   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/blkdev.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/kthread.h>
  34 #include <linux/in.h>
  35 #include <linux/cdrom.h>
  36 #include <linux/module.h>
  37 #include <linux/ratelimit.h>
  38 #include <asm/unaligned.h>
  39 #include <net/sock.h>
  40 #include <net/tcp.h>
  41 #include <scsi/scsi.h>
  42 #include <scsi/scsi_cmnd.h>
  43 #include <scsi/scsi_tcq.h>
  44
  45 #include <target/target_core_base.h>
  46 #include <target/target_core_backend.h>
  47 #include <target/target_core_fabric.h>
  48 #include <target/target_core_configfs.h>
  49
  50 #include "target_core_internal.h"
  51 #include "target_core_alua.h"
  52 #include "target_core_pr.h"
  53 #include "target_core_ua.h"
  54
  55 static struct workqueue_struct *target_completion_wq;
  56 static struct kmem_cache *se_sess_cache;
  57 struct kmem_cache *se_ua_cache;
  58 struct kmem_cache *t10_pr_reg_cache;
  59 struct kmem_cache *t10_alua_lu_gp_cache;
  60 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  61 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  62 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
  63
  64 static void transport_complete_task_attr(struct se_cmd *cmd);
  65 static void transport_handle_queue_full(struct se_cmd *cmd,
  66                 struct se_device *dev);
  67 static int transport_generic_get_mem(struct se_cmd *cmd);
  68 static void transport_put_cmd(struct se_cmd *cmd);
  69 static void target_complete_ok_work(struct work_struct *work);
  70
  71 int init_se_kmem_caches(void)
  72 {
  73         se_sess_cache = kmem_cache_create("se_sess_cache",
  74                         sizeof(struct se_session), __alignof__(struct se_session),
  75                         0, NULL);
  76         if (!se_sess_cache) {
  77                 pr_err("kmem_cache_create() for struct se_session"
  78                                 " failed\n");
  79                 goto out;
  80         }
  81         se_ua_cache = kmem_cache_create("se_ua_cache",
  82                         sizeof(struct se_ua), __alignof__(struct se_ua),
  83                         0, NULL);
  84         if (!se_ua_cache) {
  85                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  86                 goto out_free_sess_cache;
  87         }
  88         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  89                         sizeof(struct t10_pr_registration),
  90                         __alignof__(struct t10_pr_registration), 0, NULL);
  91         if (!t10_pr_reg_cache) {
  92                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  93                                 " failed\n");
  94                 goto out_free_ua_cache;
  95         }
  96         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
  97                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
  98                         0, NULL);
  99         if (!t10_alua_lu_gp_cache) {
 100                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 101                                 " failed\n");
 102                 goto out_free_pr_reg_cache;
 103         }
 104         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 105                         sizeof(struct t10_alua_lu_gp_member),
 106                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 107         if (!t10_alua_lu_gp_mem_cache) {
 108                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 109                                 "cache failed\n");
 110                 goto out_free_lu_gp_cache;
 111         }
 112         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 113                         sizeof(struct t10_alua_tg_pt_gp),
 114                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 115         if (!t10_alua_tg_pt_gp_cache) {
 116                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 117                                 "cache failed\n");
 118                 goto out_free_lu_gp_mem_cache;
 119         }
 120         t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
 121                         "t10_alua_tg_pt_gp_mem_cache",
 122                         sizeof(struct t10_alua_tg_pt_gp_member),
 123                         __alignof__(struct t10_alua_tg_pt_gp_member),
 124                         0, NULL);
 125         if (!t10_alua_tg_pt_gp_mem_cache) {
 126                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 127                                 "mem_t failed\n");
 128                 goto out_free_tg_pt_gp_cache;
 129         }
 130
 131         target_completion_wq = alloc_workqueue("target_completion",
 132                                                WQ_MEM_RECLAIM, 0);
 133         if (!target_completion_wq)
 134                 goto out_free_tg_pt_gp_mem_cache;
 135
 136         return 0;
 137
 138 out_free_tg_pt_gp_mem_cache:
 139         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 140 out_free_tg_pt_gp_cache:
 141         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 142 out_free_lu_gp_mem_cache:
 143         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 144 out_free_lu_gp_cache:
 145         kmem_cache_destroy(t10_alua_lu_gp_cache);
 146 out_free_pr_reg_cache:
 147         kmem_cache_destroy(t10_pr_reg_cache);
 148 out_free_ua_cache:
 149         kmem_cache_destroy(se_ua_cache);
 150 out_free_sess_cache:
 151         kmem_cache_destroy(se_sess_cache);
 152 out:
 153         return -ENOMEM;
 154 }
 155
 156 void release_se_kmem_caches(void)
 157 {
 158         destroy_workqueue(target_completion_wq);
 159         kmem_cache_destroy(se_sess_cache);
 160         kmem_cache_destroy(se_ua_cache);
 161         kmem_cache_destroy(t10_pr_reg_cache);
 162         kmem_cache_destroy(t10_alua_lu_gp_cache);
 163         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 164         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 165         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 166 }
 167
 168 /* This code ensures unique mib indexes are handed out. */
 169 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 170 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 171
 172 /*
 173  * Allocate a new row index for the entry type specified
 174  */
 175 u32 scsi_get_new_index(scsi_index_t type)
 176 {
 177         u32 new_index;
 178
 179         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 180
 181         spin_lock(&scsi_mib_index_lock);
 182         new_index = ++scsi_mib_index[type];
 183         spin_unlock(&scsi_mib_index_lock);
 184
 185         return new_index;
 186 }
 187
 188 void transport_subsystem_check_init(void)
 189 {
 190         int ret;
 191         static int sub_api_initialized;
 192
 193         if (sub_api_initialized)
 194                 return;
 195
 196         ret = request_module("target_core_iblock");
 197         if (ret != 0)
 198                 pr_err("Unable to load target_core_iblock\n");
 199
 200         ret = request_module("target_core_file");
 201         if (ret != 0)
 202                 pr_err("Unable to load target_core_file\n");
 203
 204         ret = request_module("target_core_pscsi");
 205         if (ret != 0)
 206                 pr_err("Unable to load target_core_pscsi\n");
 207
 208         sub_api_initialized = 1;
 209 }
 210
 211 struct se_session *transport_init_session(void)
 212 {
 213         struct se_session *se_sess;
 214
 215         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 216         if (!se_sess) {
 217                 pr_err("Unable to allocate struct se_session from"
 218                                 " se_sess_cache\n");
 219                 return ERR_PTR(-ENOMEM);
 220         }
 221         INIT_LIST_HEAD(&se_sess->sess_list);
 222         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 223         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 224         spin_lock_init(&se_sess->sess_cmd_lock);
 225         kref_init(&se_sess->sess_kref);
 226
 227         return se_sess;
 228 }
 229 EXPORT_SYMBOL(transport_init_session);
 230
 231 /*
 232  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 233  */
 234 void __transport_register_session(
 235         struct se_portal_group *se_tpg,
 236         struct se_node_acl *se_nacl,
 237         struct se_session *se_sess,
 238         void *fabric_sess_ptr)
 239 {
 240         unsigned char buf[PR_REG_ISID_LEN];
 241
 242         se_sess->se_tpg = se_tpg;
 243         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 244         /*
 245          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 246          *
 247          * Only set for struct se_session's that will actually be moving I/O.
 248          * eg: *NOT* discovery sessions.
 249          */
 250         if (se_nacl) {
 251                 /*
 252                  * If the fabric module supports an ISID based TransportID,
 253                  * save this value in binary from the fabric I_T Nexus now.
 254                  */
 255                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 256                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 257                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 258                                         &buf[0], PR_REG_ISID_LEN);
 259                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 260                 }
 261                 kref_get(&se_nacl->acl_kref);
 262
 263                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 264                 /*
 265                  * The se_nacl->nacl_sess pointer will be set to the
 266                  * last active I_T Nexus for each struct se_node_acl.
 267                  */
 268                 se_nacl->nacl_sess = se_sess;
 269
 270                 list_add_tail(&se_sess->sess_acl_list,
 271                               &se_nacl->acl_sess_list);
 272                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 273         }
 274         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 275
 276         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 277                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 278 }
 279 EXPORT_SYMBOL(__transport_register_session);
 280
 281 void transport_register_session(
 282         struct se_portal_group *se_tpg,
 283         struct se_node_acl *se_nacl,
 284         struct se_session *se_sess,
 285         void *fabric_sess_ptr)
 286 {
 287         unsigned long flags;
 288
 289         spin_lock_irqsave(&se_tpg->session_lock, flags);
 290         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 291         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 292 }
 293 EXPORT_SYMBOL(transport_register_session);
 294
 295 static void target_release_session(struct kref *kref)
 296 {
 297         struct se_session *se_sess = container_of(kref,
 298                         struct se_session, sess_kref);
 299         struct se_portal_group *se_tpg = se_sess->se_tpg;
 300
 301         se_tpg->se_tpg_tfo->close_session(se_sess);
 302 }
 303
 304 void target_get_session(struct se_session *se_sess)
 305 {
 306         kref_get(&se_sess->sess_kref);
 307 }
 308 EXPORT_SYMBOL(target_get_session);
 309
 310 void target_put_session(struct se_session *se_sess)
 311 {
 312         struct se_portal_group *tpg = se_sess->se_tpg;
 313
 314         if (tpg->se_tpg_tfo->put_session != NULL) {
 315                 tpg->se_tpg_tfo->put_session(se_sess);
 316                 return;
 317         }
 318         kref_put(&se_sess->sess_kref, target_release_session);
 319 }
 320 EXPORT_SYMBOL(target_put_session);
 321
 322 static void target_complete_nacl(struct kref *kref)
 323 {
 324         struct se_node_acl *nacl = container_of(kref,
 325                                 struct se_node_acl, acl_kref);
 326
 327         complete(&nacl->acl_free_comp);
 328 }
 329
 330 void target_put_nacl(struct se_node_acl *nacl)
 331 {
 332         kref_put(&nacl->acl_kref, target_complete_nacl);
 333 }
 334
 335 void transport_deregister_session_configfs(struct se_session *se_sess)
 336 {
 337         struct se_node_acl *se_nacl;
 338         unsigned long flags;
 339         /*
 340          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 341          */
 342         se_nacl = se_sess->se_node_acl;
 343         if (se_nacl) {
 344                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 345                 if (se_nacl->acl_stop == 0)
 346                         list_del(&se_sess->sess_acl_list);
 347                 /*
 348                  * If the session list is empty, then clear the pointer.
 349                  * Otherwise, set the struct se_session pointer from the tail
 350                  * element of the per struct se_node_acl active session list.
 351                  */
 352                 if (list_empty(&se_nacl->acl_sess_list))
 353                         se_nacl->nacl_sess = NULL;
 354                 else {
 355                         se_nacl->nacl_sess = container_of(
 356                                         se_nacl->acl_sess_list.prev,
 357                                         struct se_session, sess_acl_list);
 358                 }
 359                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 360         }
 361 }
 362 EXPORT_SYMBOL(transport_deregister_session_configfs);
 363
 364 void transport_free_session(struct se_session *se_sess)
 365 {
 366         kmem_cache_free(se_sess_cache, se_sess);
 367 }
 368 EXPORT_SYMBOL(transport_free_session);
 369
 370 void transport_deregister_session(struct se_session *se_sess)
 371 {
 372         struct se_portal_group *se_tpg = se_sess->se_tpg;
 373         struct target_core_fabric_ops *se_tfo;
 374         struct se_node_acl *se_nacl;
 375         unsigned long flags;
 376         bool comp_nacl = true;
 377
 378         if (!se_tpg) {
 379                 transport_free_session(se_sess);
 380                 return;
 381         }
 382         se_tfo = se_tpg->se_tpg_tfo;
 383
 384         spin_lock_irqsave(&se_tpg->session_lock, flags);
 385         list_del(&se_sess->sess_list);
 386         se_sess->se_tpg = NULL;
 387         se_sess->fabric_sess_ptr = NULL;
 388         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 389
 390         /*
 391          * Determine if we need to do extra work for this initiator node's
 392          * struct se_node_acl if it had been previously dynamically generated.
 393          */
 394         se_nacl = se_sess->se_node_acl;
 395
 396         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 397         if (se_nacl && se_nacl->dynamic_node_acl) {
 398                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 399                         list_del(&se_nacl->acl_list);
 400                         se_tpg->num_node_acls--;
 401                         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 402                         core_tpg_wait_for_nacl_pr_ref(se_nacl);
 403                         core_free_device_list_for_node(se_nacl, se_tpg);
 404                         se_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
 405
 406                         comp_nacl = false;
 407                         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 408                 }
 409         }
 410         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 411
 412         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 413                 se_tpg->se_tpg_tfo->get_fabric_name());
 414         /*
 415          * If last kref is dropping now for an explict NodeACL, awake sleeping
 416          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 417          * removal context.
 418          */
 419         if (se_nacl && comp_nacl == true)
 420                 target_put_nacl(se_nacl);
 421
 422         transport_free_session(se_sess);
 423 }
 424 EXPORT_SYMBOL(transport_deregister_session);
 425
 426 /*
 427  * Called with cmd->t_state_lock held.
 428  */
 429 static void target_remove_from_state_list(struct se_cmd *cmd)
 430 {
 431         struct se_device *dev = cmd->se_dev;
 432         unsigned long flags;
 433
 434         if (!dev)
 435                 return;
 436
 437         if (cmd->transport_state & CMD_T_BUSY)
 438                 return;
 439
 440         spin_lock_irqsave(&dev->execute_task_lock, flags);
 441         if (cmd->state_active) {
 442                 list_del(&cmd->state_list);
 443                 cmd->state_active = false;
 444         }
 445         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 446 }
 447
 448 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists)
 449 {
 450         unsigned long flags;
 451
 452         spin_lock_irqsave(&cmd->t_state_lock, flags);
 453         /*
 454          * Determine if IOCTL context caller in requesting the stopping of this
 455          * command for LUN shutdown purposes.
 456          */
 457         if (cmd->transport_state & CMD_T_LUN_STOP) {
 458                 pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
 459                         __func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
 460
 461                 cmd->transport_state &= ~CMD_T_ACTIVE;
 462                 if (remove_from_lists)
 463                         target_remove_from_state_list(cmd);
 464                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 465
 466                 complete(&cmd->transport_lun_stop_comp);
 467                 return 1;
 468         }
 469
 470         if (remove_from_lists) {
 471                 target_remove_from_state_list(cmd);
 472
 473                 /*
 474                  * Clear struct se_cmd->se_lun before the handoff to FE.
 475                  */
 476                 cmd->se_lun = NULL;
 477         }
 478
 479         /*
 480          * Determine if frontend context caller is requesting the stopping of
 481          * this command for frontend exceptions.
 482          */
 483         if (cmd->transport_state & CMD_T_STOP) {
 484                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
 485                         __func__, __LINE__,
 486                         cmd->se_tfo->get_task_tag(cmd));
 487
 488                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 489
 490                 complete(&cmd->t_transport_stop_comp);
 491                 return 1;
 492         }
 493
 494         cmd->transport_state &= ~CMD_T_ACTIVE;
 495         if (remove_from_lists) {
 496                 /*
 497                  * Some fabric modules like tcm_loop can release
 498                  * their internally allocated I/O reference now and
 499                  * struct se_cmd now.
 500                  *
 501                  * Fabric modules are expected to return '1' here if the
 502                  * se_cmd being passed is released at this point,
 503                  * or zero if not being released.
 504                  */
 505                 if (cmd->se_tfo->check_stop_free != NULL) {
 506                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 507                         return cmd->se_tfo->check_stop_free(cmd);
 508                 }
 509         }
 510
 511         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 512         return 0;
 513 }
 514
 515 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 516 {
 517         return transport_cmd_check_stop(cmd, true);
 518 }
 519
 520 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 521 {
 522         struct se_lun *lun = cmd->se_lun;
 523         unsigned long flags;
 524
 525         if (!lun)
 526                 return;
 527
 528         spin_lock_irqsave(&cmd->t_state_lock, flags);
 529         if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
 530                 cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
 531                 target_remove_from_state_list(cmd);
 532         }
 533         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 534
 535         spin_lock_irqsave(&lun->lun_cmd_lock, flags);
 536         if (!list_empty(&cmd->se_lun_node))
 537                 list_del_init(&cmd->se_lun_node);
 538         spin_unlock_irqrestore(&lun->lun_cmd_lock, flags);
 539 }
 540
 541 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 542 {
 543         if (transport_cmd_check_stop_to_fabric(cmd))
 544                 return;
 545         if (remove)
 546                 transport_put_cmd(cmd);
 547 }
 548
 549 static void target_complete_failure_work(struct work_struct *work)
 550 {
 551         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 552
 553         transport_generic_request_failure(cmd,
 554                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 555 }
 556
 557 /*
 558  * Used when asking transport to copy Sense Data from the underlying
 559  * Linux/SCSI struct scsi_cmnd
 560  */
 561 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 562 {
 563         struct se_device *dev = cmd->se_dev;
 564
 565         WARN_ON(!cmd->se_lun);
 566
 567         if (!dev)
 568                 return NULL;
 569
 570         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 571                 return NULL;
 572
 573         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 574
 575         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 576                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 577         return cmd->sense_buffer;
 578 }
 579
 580 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 581 {
 582         struct se_device *dev = cmd->se_dev;
 583         int success = scsi_status == GOOD;
 584         unsigned long flags;
 585
 586         cmd->scsi_status = scsi_status;
 587
 588
 589         spin_lock_irqsave(&cmd->t_state_lock, flags);
 590         cmd->transport_state &= ~CMD_T_BUSY;
 591
 592         if (dev && dev->transport->transport_complete) {
 593                 dev->transport->transport_complete(cmd,
 594                                 cmd->t_data_sg,
 595                                 transport_get_sense_buffer(cmd));
 596                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 597                         success = 1;
 598         }
 599
 600         /*
 601          * See if we are waiting to complete for an exception condition.
 602          */
 603         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
 604                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 605                 complete(&cmd->task_stop_comp);
 606                 return;
 607         }
 608
 609         if (!success)
 610                 cmd->transport_state |= CMD_T_FAILED;
 611
 612         /*
 613          * Check for case where an explict ABORT_TASK has been received
 614          * and transport_wait_for_tasks() will be waiting for completion..
 615          */
 616         if (cmd->transport_state & CMD_T_ABORTED &&
 617             cmd->transport_state & CMD_T_STOP) {
 618                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 619                 complete(&cmd->t_transport_stop_comp);
 620                 return;
 621         } else if (cmd->transport_state & CMD_T_FAILED) {
 622                 INIT_WORK(&cmd->work, target_complete_failure_work);
 623         } else {
 624                 INIT_WORK(&cmd->work, target_complete_ok_work);
 625         }
 626
 627         cmd->t_state = TRANSPORT_COMPLETE;
 628         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 629         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 630
 631         queue_work(target_completion_wq, &cmd->work);
 632 }
 633 EXPORT_SYMBOL(target_complete_cmd);
 634
 635 static void target_add_to_state_list(struct se_cmd *cmd)
 636 {
 637         struct se_device *dev = cmd->se_dev;
 638         unsigned long flags;
 639
 640         spin_lock_irqsave(&dev->execute_task_lock, flags);
 641         if (!cmd->state_active) {
 642                 list_add_tail(&cmd->state_list, &dev->state_list);
 643                 cmd->state_active = true;
 644         }
 645         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 646 }
 647
 648 /*
 649  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 650  */
 651 static void transport_write_pending_qf(struct se_cmd *cmd);
 652 static void transport_complete_qf(struct se_cmd *cmd);
 653
 654 void target_qf_do_work(struct work_struct *work)
 655 {
 656         struct se_device *dev = container_of(work, struct se_device,
 657                                         qf_work_queue);
 658         LIST_HEAD(qf_cmd_list);
 659         struct se_cmd *cmd, *cmd_tmp;
 660
 661         spin_lock_irq(&dev->qf_cmd_lock);
 662         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 663         spin_unlock_irq(&dev->qf_cmd_lock);
 664
 665         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 666                 list_del(&cmd->se_qf_node);
 667                 atomic_dec(&dev->dev_qf_count);
 668                 smp_mb__after_atomic_dec();
 669
 670                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 671                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 672                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 673                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 674                         : "UNKNOWN");
 675
 676                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 677                         transport_write_pending_qf(cmd);
 678                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 679                         transport_complete_qf(cmd);
 680         }
 681 }
 682
 683 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 684 {
 685         switch (cmd->data_direction) {
 686         case DMA_NONE:
 687                 return "NONE";
 688         case DMA_FROM_DEVICE:
 689                 return "READ";
 690         case DMA_TO_DEVICE:
 691                 return "WRITE";
 692         case DMA_BIDIRECTIONAL:
 693                 return "BIDI";
 694         default:
 695                 break;
 696         }
 697
 698         return "UNKNOWN";
 699 }
 700
 701 void transport_dump_dev_state(
 702         struct se_device *dev,
 703         char *b,
 704         int *bl)
 705 {
 706         *bl += sprintf(b + *bl, "Status: ");
 707         if (dev->export_count)
 708                 *bl += sprintf(b + *bl, "ACTIVATED");
 709         else
 710                 *bl += sprintf(b + *bl, "DEACTIVATED");
 711
 712         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 713         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 714                 dev->dev_attrib.block_size,
 715                 dev->dev_attrib.hw_max_sectors);
 716         *bl += sprintf(b + *bl, "        ");
 717 }
 718
 719 void transport_dump_vpd_proto_id(
 720         struct t10_vpd *vpd,
 721         unsigned char *p_buf,
 722         int p_buf_len)
 723 {
 724         unsigned char buf[VPD_TMP_BUF_SIZE];
 725         int len;
 726
 727         memset(buf, 0, VPD_TMP_BUF_SIZE);
 728         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 729
 730         switch (vpd->protocol_identifier) {
 731         case 0x00:
 732                 sprintf(buf+len, "Fibre Channel\n");
 733                 break;
 734         case 0x10:
 735                 sprintf(buf+len, "Parallel SCSI\n");
 736                 break;
 737         case 0x20:
 738                 sprintf(buf+len, "SSA\n");
 739                 break;
 740         case 0x30:
 741                 sprintf(buf+len, "IEEE 1394\n");
 742                 break;
 743         case 0x40:
 744                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 745                                 " Protocol\n");
 746                 break;
 747         case 0x50:
 748                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 749                 break;
 750         case 0x60:
 751                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 752                 break;
 753         case 0x70:
 754                 sprintf(buf+len, "Automation/Drive Interface Transport"
 755                                 " Protocol\n");
 756                 break;
 757         case 0x80:
 758                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 759                 break;
 760         default:
 761                 sprintf(buf+len, "Unknown 0x%02x\n",
 762                                 vpd->protocol_identifier);
 763                 break;
 764         }
 765
 766         if (p_buf)
 767                 strncpy(p_buf, buf, p_buf_len);
 768         else
 769                 pr_debug("%s", buf);
 770 }
 771
 772 void
 773 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 774 {
 775         /*
 776          * Check if the Protocol Identifier Valid (PIV) bit is set..
 777          *
 778          * from spc3r23.pdf section 7.5.1
 779          */
 780          if (page_83[1] & 0x80) {
 781                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 782                 vpd->protocol_identifier_set = 1;
 783                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 784         }
 785 }
 786 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 787
 788 int transport_dump_vpd_assoc(
 789         struct t10_vpd *vpd,
 790         unsigned char *p_buf,
 791         int p_buf_len)
 792 {
 793         unsigned char buf[VPD_TMP_BUF_SIZE];
 794         int ret = 0;
 795         int len;
 796
 797         memset(buf, 0, VPD_TMP_BUF_SIZE);
 798         len = sprintf(buf, "T10 VPD Identifier Association: ");
 799
 800         switch (vpd->association) {
 801         case 0x00:
 802                 sprintf(buf+len, "addressed logical unit\n");
 803                 break;
 804         case 0x10:
 805                 sprintf(buf+len, "target port\n");
 806                 break;
 807         case 0x20:
 808                 sprintf(buf+len, "SCSI target device\n");
 809                 break;
 810         default:
 811                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 812                 ret = -EINVAL;
 813                 break;
 814         }
 815
 816         if (p_buf)
 817                 strncpy(p_buf, buf, p_buf_len);
 818         else
 819                 pr_debug("%s", buf);
 820
 821         return ret;
 822 }
 823
 824 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 825 {
 826         /*
 827          * The VPD identification association..
 828          *
 829          * from spc3r23.pdf Section 7.6.3.1 Table 297
 830          */
 831         vpd->association = (page_83[1] & 0x30);
 832         return transport_dump_vpd_assoc(vpd, NULL, 0);
 833 }
 834 EXPORT_SYMBOL(transport_set_vpd_assoc);
 835
 836 int transport_dump_vpd_ident_type(
 837         struct t10_vpd *vpd,
 838         unsigned char *p_buf,
 839         int p_buf_len)
 840 {
 841         unsigned char buf[VPD_TMP_BUF_SIZE];
 842         int ret = 0;
 843         int len;
 844
 845         memset(buf, 0, VPD_TMP_BUF_SIZE);
 846         len = sprintf(buf, "T10 VPD Identifier Type: ");
 847
 848         switch (vpd->device_identifier_type) {
 849         case 0x00:
 850                 sprintf(buf+len, "Vendor specific\n");
 851                 break;
 852         case 0x01:
 853                 sprintf(buf+len, "T10 Vendor ID based\n");
 854                 break;
 855         case 0x02:
 856                 sprintf(buf+len, "EUI-64 based\n");
 857                 break;
 858         case 0x03:
 859                 sprintf(buf+len, "NAA\n");
 860                 break;
 861         case 0x04:
 862                 sprintf(buf+len, "Relative target port identifier\n");
 863                 break;
 864         case 0x08:
 865                 sprintf(buf+len, "SCSI name string\n");
 866                 break;
 867         default:
 868                 sprintf(buf+len, "Unsupported: 0x%02x\n",
 869                                 vpd->device_identifier_type);
 870                 ret = -EINVAL;
 871                 break;
 872         }
 873
 874         if (p_buf) {
 875                 if (p_buf_len < strlen(buf)+1)
 876                         return -EINVAL;
 877                 strncpy(p_buf, buf, p_buf_len);
 878         } else {
 879                 pr_debug("%s", buf);
 880         }
 881
 882         return ret;
 883 }
 884
 885 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
 886 {
 887         /*
 888          * The VPD identifier type..
 889          *
 890          * from spc3r23.pdf Section 7.6.3.1 Table 298
 891          */
 892         vpd->device_identifier_type = (page_83[1] & 0x0f);
 893         return transport_dump_vpd_ident_type(vpd, NULL, 0);
 894 }
 895 EXPORT_SYMBOL(transport_set_vpd_ident_type);
 896
 897 int transport_dump_vpd_ident(
 898         struct t10_vpd *vpd,
 899         unsigned char *p_buf,
 900         int p_buf_len)
 901 {
 902         unsigned char buf[VPD_TMP_BUF_SIZE];
 903         int ret = 0;
 904
 905         memset(buf, 0, VPD_TMP_BUF_SIZE);
 906
 907         switch (vpd->device_identifier_code_set) {
 908         case 0x01: /* Binary */
 909                 snprintf(buf, sizeof(buf),
 910                         "T10 VPD Binary Device Identifier: %s\n",
 911                         &vpd->device_identifier[0]);
 912                 break;
 913         case 0x02: /* ASCII */
 914                 snprintf(buf, sizeof(buf),
 915                         "T10 VPD ASCII Device Identifier: %s\n",
 916                         &vpd->device_identifier[0]);
 917                 break;
 918         case 0x03: /* UTF-8 */
 919                 snprintf(buf, sizeof(buf),
 920                         "T10 VPD UTF-8 Device Identifier: %s\n",
 921                         &vpd->device_identifier[0]);
 922                 break;
 923         default:
 924                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
 925                         " 0x%02x", vpd->device_identifier_code_set);
 926                 ret = -EINVAL;
 927                 break;
 928         }
 929
 930         if (p_buf)
 931                 strncpy(p_buf, buf, p_buf_len);
 932         else
 933                 pr_debug("%s", buf);
 934
 935         return ret;
 936 }
 937
 938 int
 939 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
 940 {
 941         static const char hex_str[] = "0123456789abcdef";
 942         int j = 0, i = 4; /* offset to start of the identifier */
 943
 944         /*
 945          * The VPD Code Set (encoding)
 946          *
 947          * from spc3r23.pdf Section 7.6.3.1 Table 296
 948          */
 949         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
 950         switch (vpd->device_identifier_code_set) {
 951         case 0x01: /* Binary */
 952                 vpd->device_identifier[j++] =
 953                                 hex_str[vpd->device_identifier_type];
 954                 while (i < (4 + page_83[3])) {
 955                         vpd->device_identifier[j++] =
 956                                 hex_str[(page_83[i] & 0xf0) >> 4];
 957                         vpd->device_identifier[j++] =
 958                                 hex_str[page_83[i] & 0x0f];
 959                         i++;
 960                 }
 961                 break;
 962         case 0x02: /* ASCII */
 963         case 0x03: /* UTF-8 */
 964                 while (i < (4 + page_83[3]))
 965                         vpd->device_identifier[j++] = page_83[i++];
 966                 break;
 967         default:
 968                 break;
 969         }
 970
 971         return transport_dump_vpd_ident(vpd, NULL, 0);
 972 }
 973 EXPORT_SYMBOL(transport_set_vpd_ident);
 974
 975 sense_reason_t
 976 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
 977 {
 978         struct se_device *dev = cmd->se_dev;
 979
 980         if (cmd->unknown_data_length) {
 981                 cmd->data_length = size;
 982         } else if (size != cmd->data_length) {
 983                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
 984                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
 985                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
 986                                 cmd->data_length, size, cmd->t_task_cdb[0]);
 987
 988                 if (cmd->data_direction == DMA_TO_DEVICE) {
 989                         pr_err("Rejecting underflow/overflow"
 990                                         " WRITE data\n");
 991                         return TCM_INVALID_CDB_FIELD;
 992                 }
 993                 /*
 994                  * Reject READ_* or WRITE_* with overflow/underflow for
 995                  * type SCF_SCSI_DATA_CDB.
 996                  */
 997                 if (dev->dev_attrib.block_size != 512)  {
 998                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
 999                                 " CDB on non 512-byte sector setup subsystem"
1000                                 " plugin: %s\n", dev->transport->name);
1001                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1002                         return TCM_INVALID_CDB_FIELD;
1003                 }
1004                 /*
1005                  * For the overflow case keep the existing fabric provided
1006                  * ->data_length.  Otherwise for the underflow case, reset
1007                  * ->data_length to the smaller SCSI expected data transfer
1008                  * length.
1009                  */
1010                 if (size > cmd->data_length) {
1011                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1012                         cmd->residual_count = (size - cmd->data_length);
1013                 } else {
1014                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1015                         cmd->residual_count = (cmd->data_length - size);
1016                         cmd->data_length = size;
1017                 }
1018         }
1019
1020         return 0;
1021
1022 }
1023
1024 /*
1025  * Used by fabric modules containing a local struct se_cmd within their
1026  * fabric dependent per I/O descriptor.
1027  */
1028 void transport_init_se_cmd(
1029         struct se_cmd *cmd,
1030         struct target_core_fabric_ops *tfo,
1031         struct se_session *se_sess,
1032         u32 data_length,
1033         int data_direction,
1034         int task_attr,
1035         unsigned char *sense_buffer)
1036 {
1037         INIT_LIST_HEAD(&cmd->se_lun_node);
1038         INIT_LIST_HEAD(&cmd->se_delayed_node);
1039         INIT_LIST_HEAD(&cmd->se_qf_node);
1040         INIT_LIST_HEAD(&cmd->se_cmd_list);
1041         INIT_LIST_HEAD(&cmd->state_list);
1042         init_completion(&cmd->transport_lun_fe_stop_comp);
1043         init_completion(&cmd->transport_lun_stop_comp);
1044         init_completion(&cmd->t_transport_stop_comp);
1045         init_completion(&cmd->cmd_wait_comp);
1046         init_completion(&cmd->task_stop_comp);
1047         spin_lock_init(&cmd->t_state_lock);
1048         cmd->transport_state = CMD_T_DEV_ACTIVE;
1049
1050         cmd->se_tfo = tfo;
1051         cmd->se_sess = se_sess;
1052         cmd->data_length = data_length;
1053         cmd->data_direction = data_direction;
1054         cmd->sam_task_attr = task_attr;
1055         cmd->sense_buffer = sense_buffer;
1056
1057         cmd->state_active = false;
1058 }
1059 EXPORT_SYMBOL(transport_init_se_cmd);
1060
1061 static sense_reason_t
1062 transport_check_alloc_task_attr(struct se_cmd *cmd)
1063 {
1064         struct se_device *dev = cmd->se_dev;
1065
1066         /*
1067          * Check if SAM Task Attribute emulation is enabled for this
1068          * struct se_device storage object
1069          */
1070         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1071                 return 0;
1072
1073         if (cmd->sam_task_attr == MSG_ACA_TAG) {
1074                 pr_debug("SAM Task Attribute ACA"
1075                         " emulation is not supported\n");
1076                 return TCM_INVALID_CDB_FIELD;
1077         }
1078         /*
1079          * Used to determine when ORDERED commands should go from
1080          * Dormant to Active status.
1081          */
1082         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1083         smp_mb__after_atomic_inc();
1084         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1085                         cmd->se_ordered_id, cmd->sam_task_attr,
1086                         dev->transport->name);
1087         return 0;
1088 }
1089
1090 sense_reason_t
1091 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1092 {
1093         struct se_device *dev = cmd->se_dev;
1094         unsigned long flags;
1095         sense_reason_t ret;
1096
1097         /*
1098          * Ensure that the received CDB is less than the max (252 + 8) bytes
1099          * for VARIABLE_LENGTH_CMD
1100          */
1101         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1102                 pr_err("Received SCSI CDB with command_size: %d that"
1103                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1104                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1105                 return TCM_INVALID_CDB_FIELD;
1106         }
1107         /*
1108          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1109          * allocate the additional extended CDB buffer now..  Otherwise
1110          * setup the pointer from __t_task_cdb to t_task_cdb.
1111          */
1112         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1113                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1114                                                 GFP_KERNEL);
1115                 if (!cmd->t_task_cdb) {
1116                         pr_err("Unable to allocate cmd->t_task_cdb"
1117                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1118                                 scsi_command_size(cdb),
1119                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1120                         return TCM_OUT_OF_RESOURCES;
1121                 }
1122         } else
1123                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1124         /*
1125          * Copy the original CDB into cmd->
1126          */
1127         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1128
1129         /*
1130          * Check for an existing UNIT ATTENTION condition
1131          */
1132         ret = target_scsi3_ua_check(cmd);
1133         if (ret)
1134                 return ret;
1135
1136         ret = target_alua_state_check(cmd);
1137         if (ret)
1138                 return ret;
1139
1140         ret = target_check_reservation(cmd);
1141         if (ret) {
1142                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1143                 return ret;
1144         }
1145
1146         ret = dev->transport->parse_cdb(cmd);
1147         if (ret)
1148                 return ret;
1149
1150         ret = transport_check_alloc_task_attr(cmd);
1151         if (ret)
1152                 return ret;
1153
1154         spin_lock_irqsave(&cmd->t_state_lock, flags);
1155         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1156         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1157
1158         spin_lock(&cmd->se_lun->lun_sep_lock);
1159         if (cmd->se_lun->lun_sep)
1160                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1161         spin_unlock(&cmd->se_lun->lun_sep_lock);
1162         return 0;
1163 }
1164 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1165
1166 /*
1167  * Used by fabric module frontends to queue tasks directly.
1168  * Many only be used from process context only
1169  */
1170 int transport_handle_cdb_direct(
1171         struct se_cmd *cmd)
1172 {
1173         sense_reason_t ret;
1174
1175         if (!cmd->se_lun) {
1176                 dump_stack();
1177                 pr_err("cmd->se_lun is NULL\n");
1178                 return -EINVAL;
1179         }
1180         if (in_interrupt()) {
1181                 dump_stack();
1182                 pr_err("transport_generic_handle_cdb cannot be called"
1183                                 " from interrupt context\n");
1184                 return -EINVAL;
1185         }
1186         /*
1187          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1188          * outstanding descriptors are handled correctly during shutdown via
1189          * transport_wait_for_tasks()
1190          *
1191          * Also, we don't take cmd->t_state_lock here as we only expect
1192          * this to be called for initial descriptor submission.
1193          */
1194         cmd->t_state = TRANSPORT_NEW_CMD;
1195         cmd->transport_state |= CMD_T_ACTIVE;
1196
1197         /*
1198          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1199          * so follow TRANSPORT_NEW_CMD processing thread context usage
1200          * and call transport_generic_request_failure() if necessary..
1201          */
1202         ret = transport_generic_new_cmd(cmd);
1203         if (ret)
1204                 transport_generic_request_failure(cmd, ret);
1205         return 0;
1206 }
1207 EXPORT_SYMBOL(transport_handle_cdb_direct);
1208
1209 static sense_reason_t
1210 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1211                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1212 {
1213         if (!sgl || !sgl_count)
1214                 return 0;
1215
1216         /*
1217          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1218          * scatterlists already have been set to follow what the fabric
1219          * passes for the original expected data transfer length.
1220          */
1221         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1222                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1223                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1224                 return TCM_INVALID_CDB_FIELD;
1225         }
1226
1227         cmd->t_data_sg = sgl;
1228         cmd->t_data_nents = sgl_count;
1229
1230         if (sgl_bidi && sgl_bidi_count) {
1231                 cmd->t_bidi_data_sg = sgl_bidi;
1232                 cmd->t_bidi_data_nents = sgl_bidi_count;
1233         }
1234         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1235         return 0;
1236 }
1237
1238 /*
1239  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1240  *                       se_cmd + use pre-allocated SGL memory.
1241  *
1242  * @se_cmd: command descriptor to submit
1243  * @se_sess: associated se_sess for endpoint
1244  * @cdb: pointer to SCSI CDB
1245  * @sense: pointer to SCSI sense buffer
1246  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1247  * @data_length: fabric expected data transfer length
1248  * @task_addr: SAM task attribute
1249  * @data_dir: DMA data direction
1250  * @flags: flags for command submission from target_sc_flags_tables
1251  * @sgl: struct scatterlist memory for unidirectional mapping
1252  * @sgl_count: scatterlist count for unidirectional mapping
1253  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1254  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1255  *
1256  * Returns non zero to signal active I/O shutdown failure.  All other
1257  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1258  * but still return zero here.
1259  *
1260  * This may only be called from process context, and also currently
1261  * assumes internal allocation of fabric payload buffer by target-core.
1262  */
1263 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1264                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1265                 u32 data_length, int task_attr, int data_dir, int flags,
1266                 struct scatterlist *sgl, u32 sgl_count,
1267                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1268 {
1269         struct se_portal_group *se_tpg;
1270         sense_reason_t rc;
1271         int ret;
1272
1273         se_tpg = se_sess->se_tpg;
1274         BUG_ON(!se_tpg);
1275         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1276         BUG_ON(in_interrupt());
1277         /*
1278          * Initialize se_cmd for target operation.  From this point
1279          * exceptions are handled by sending exception status via
1280          * target_core_fabric_ops->queue_status() callback
1281          */
1282         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1283                                 data_length, data_dir, task_attr, sense);
1284         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1285                 se_cmd->unknown_data_length = 1;
1286         /*
1287          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1288          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1289          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1290          * kref_put() to happen during fabric packet acknowledgement.
1291          */
1292         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1293         if (ret)
1294                 return ret;
1295         /*
1296          * Signal bidirectional data payloads to target-core
1297          */
1298         if (flags & TARGET_SCF_BIDI_OP)
1299                 se_cmd->se_cmd_flags |= SCF_BIDI;
1300         /*
1301          * Locate se_lun pointer and attach it to struct se_cmd
1302          */
1303         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1304         if (rc) {
1305                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1306                 target_put_sess_cmd(se_sess, se_cmd);
1307                 return 0;
1308         }
1309
1310         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1311         if (rc != 0) {
1312                 transport_generic_request_failure(se_cmd, rc);
1313                 return 0;
1314         }
1315         /*
1316          * When a non zero sgl_count has been passed perform SGL passthrough
1317          * mapping for pre-allocated fabric memory instead of having target
1318          * core perform an internal SGL allocation..
1319          */
1320         if (sgl_count != 0) {
1321                 BUG_ON(!sgl);
1322
1323                 /*
1324                  * A work-around for tcm_loop as some userspace code via
1325                  * scsi-generic do not memset their associated read buffers,
1326                  * so go ahead and do that here for type non-data CDBs.  Also
1327                  * note that this is currently guaranteed to be a single SGL
1328                  * for this case by target core in target_setup_cmd_from_cdb()
1329                  * -> transport_generic_cmd_sequencer().
1330                  */
1331                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1332                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1333                         unsigned char *buf = NULL;
1334
1335                         if (sgl)
1336                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1337
1338                         if (buf) {
1339                                 memset(buf, 0, sgl->length);
1340                                 kunmap(sg_page(sgl));
1341                         }
1342                 }
1343
1344                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1345                                 sgl_bidi, sgl_bidi_count);
1346                 if (rc != 0) {
1347                         transport_generic_request_failure(se_cmd, rc);
1348                         return 0;
1349                 }
1350         }
1351         /*
1352          * Check if we need to delay processing because of ALUA
1353          * Active/NonOptimized primary access state..
1354          */
1355         core_alua_check_nonop_delay(se_cmd);
1356
1357         transport_handle_cdb_direct(se_cmd);
1358         return 0;
1359 }
1360 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1361
1362 /*
1363  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1364  *
1365  * @se_cmd: command descriptor to submit
1366  * @se_sess: associated se_sess for endpoint
1367  * @cdb: pointer to SCSI CDB
1368  * @sense: pointer to SCSI sense buffer
1369  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1370  * @data_length: fabric expected data transfer length
1371  * @task_addr: SAM task attribute
1372  * @data_dir: DMA data direction
1373  * @flags: flags for command submission from target_sc_flags_tables
1374  *
1375  * Returns non zero to signal active I/O shutdown failure.  All other
1376  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1377  * but still return zero here.
1378  *
1379  * This may only be called from process context, and also currently
1380  * assumes internal allocation of fabric payload buffer by target-core.
1381  *
1382  * It also assumes interal target core SGL memory allocation.
1383  */
1384 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1385                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1386                 u32 data_length, int task_attr, int data_dir, int flags)
1387 {
1388         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1389                         unpacked_lun, data_length, task_attr, data_dir,
1390                         flags, NULL, 0, NULL, 0);
1391 }
1392 EXPORT_SYMBOL(target_submit_cmd);
1393
1394 static void target_complete_tmr_failure(struct work_struct *work)
1395 {
1396         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1397
1398         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1399         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1400
1401         transport_cmd_check_stop_to_fabric(se_cmd);
1402 }
1403
1404 /**
1405  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1406  *                     for TMR CDBs
1407  *
1408  * @se_cmd: command descriptor to submit
1409  * @se_sess: associated se_sess for endpoint
1410  * @sense: pointer to SCSI sense buffer
1411  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1412  * @fabric_context: fabric context for TMR req
1413  * @tm_type: Type of TM request
1414  * @gfp: gfp type for caller
1415  * @tag: referenced task tag for TMR_ABORT_TASK
1416  * @flags: submit cmd flags
1417  *
1418  * Callable from all contexts.
1419  **/
1420
1421 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1422                 unsigned char *sense, u32 unpacked_lun,
1423                 void *fabric_tmr_ptr, unsigned char tm_type,
1424                 gfp_t gfp, unsigned int tag, int flags)
1425 {
1426         struct se_portal_group *se_tpg;
1427         int ret;
1428
1429         se_tpg = se_sess->se_tpg;
1430         BUG_ON(!se_tpg);
1431
1432         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1433                               0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1434         /*
1435          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1436          * allocation failure.
1437          */
1438         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1439         if (ret < 0)
1440                 return -ENOMEM;
1441
1442         if (tm_type == TMR_ABORT_TASK)
1443                 se_cmd->se_tmr_req->ref_task_tag = tag;
1444
1445         /* See target_submit_cmd for commentary */
1446         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1447         if (ret) {
1448                 core_tmr_release_req(se_cmd->se_tmr_req);
1449                 return ret;
1450         }
1451
1452         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1453         if (ret) {
1454                 /*
1455                  * For callback during failure handling, push this work off
1456                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1457                  */
1458                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1459                 schedule_work(&se_cmd->work);
1460                 return 0;
1461         }
1462         transport_generic_handle_tmr(se_cmd);
1463         return 0;
1464 }
1465 EXPORT_SYMBOL(target_submit_tmr);
1466
1467 /*
1468  * If the cmd is active, request it to be stopped and sleep until it
1469  * has completed.
1470  */
1471 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1472 {
1473         bool was_active = false;
1474
1475         if (cmd->transport_state & CMD_T_BUSY) {
1476                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1477                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1478
1479                 pr_debug("cmd %p waiting to complete\n", cmd);
1480                 wait_for_completion(&cmd->task_stop_comp);
1481                 pr_debug("cmd %p stopped successfully\n", cmd);
1482
1483                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1484                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1485                 cmd->transport_state &= ~CMD_T_BUSY;
1486                 was_active = true;
1487         }
1488
1489         return was_active;
1490 }
1491
1492 /*
1493  * Handle SAM-esque emulation for generic transport request failures.
1494  */
1495 void transport_generic_request_failure(struct se_cmd *cmd,
1496                 sense_reason_t sense_reason)
1497 {
1498         int ret = 0;
1499
1500         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1501                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1502                 cmd->t_task_cdb[0]);
1503         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1504                 cmd->se_tfo->get_cmd_state(cmd),
1505                 cmd->t_state, sense_reason);
1506         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1507                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1508                 (cmd->transport_state & CMD_T_STOP) != 0,
1509                 (cmd->transport_state & CMD_T_SENT) != 0);
1510
1511         /*
1512          * For SAM Task Attribute emulation for failed struct se_cmd
1513          */
1514         transport_complete_task_attr(cmd);
1515
1516         switch (sense_reason) {
1517         case TCM_NON_EXISTENT_LUN:
1518         case TCM_UNSUPPORTED_SCSI_OPCODE:
1519         case TCM_INVALID_CDB_FIELD:
1520         case TCM_INVALID_PARAMETER_LIST:
1521         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1522         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1523         case TCM_UNKNOWN_MODE_PAGE:
1524         case TCM_WRITE_PROTECTED:
1525         case TCM_ADDRESS_OUT_OF_RANGE:
1526         case TCM_CHECK_CONDITION_ABORT_CMD:
1527         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1528         case TCM_CHECK_CONDITION_NOT_READY:
1529                 break;
1530         case TCM_OUT_OF_RESOURCES:
1531                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1532                 break;
1533         case TCM_RESERVATION_CONFLICT:
1534                 /*
1535                  * No SENSE Data payload for this case, set SCSI Status
1536                  * and queue the response to $FABRIC_MOD.
1537                  *
1538                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1539                  */
1540                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1541                 /*
1542                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1543                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1544                  * CONFLICT STATUS.
1545                  *
1546                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1547                  */
1548                 if (cmd->se_sess &&
1549                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1550                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1551                                 cmd->orig_fe_lun, 0x2C,
1552                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1553
1554                 ret = cmd->se_tfo->queue_status(cmd);
1555                 if (ret == -EAGAIN || ret == -ENOMEM)
1556                         goto queue_full;
1557                 goto check_stop;
1558         default:
1559                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1560                         cmd->t_task_cdb[0], sense_reason);
1561                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1562                 break;
1563         }
1564
1565         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1566         if (ret == -EAGAIN || ret == -ENOMEM)
1567                 goto queue_full;
1568
1569 check_stop:
1570         transport_lun_remove_cmd(cmd);
1571         if (!transport_cmd_check_stop_to_fabric(cmd))
1572                 ;
1573         return;
1574
1575 queue_full:
1576         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1577         transport_handle_queue_full(cmd, cmd->se_dev);
1578 }
1579 EXPORT_SYMBOL(transport_generic_request_failure);
1580
1581 static void __target_execute_cmd(struct se_cmd *cmd)
1582 {
1583         sense_reason_t ret;
1584
1585         spin_lock_irq(&cmd->t_state_lock);
1586         cmd->transport_state |= (CMD_T_BUSY|CMD_T_SENT);
1587         spin_unlock_irq(&cmd->t_state_lock);
1588
1589         if (cmd->execute_cmd) {
1590                 ret = cmd->execute_cmd(cmd);
1591                 if (ret) {
1592                         spin_lock_irq(&cmd->t_state_lock);
1593                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1594                         spin_unlock_irq(&cmd->t_state_lock);
1595
1596                         transport_generic_request_failure(cmd, ret);
1597                 }
1598         }
1599 }
1600
1601 static bool target_handle_task_attr(struct se_cmd *cmd)
1602 {
1603         struct se_device *dev = cmd->se_dev;
1604
1605         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1606                 return false;
1607
1608         /*
1609          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1610          * to allow the passed struct se_cmd list of tasks to the front of the list.
1611          */
1612         switch (cmd->sam_task_attr) {
1613         case MSG_HEAD_TAG:
1614                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1615                          "se_ordered_id: %u\n",
1616                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1617                 return false;
1618         case MSG_ORDERED_TAG:
1619                 atomic_inc(&dev->dev_ordered_sync);
1620                 smp_mb__after_atomic_inc();
1621
1622                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1623                          " se_ordered_id: %u\n",
1624                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1625
1626                 /*
1627                  * Execute an ORDERED command if no other older commands
1628                  * exist that need to be completed first.
1629                  */
1630                 if (!atomic_read(&dev->simple_cmds))
1631                         return false;
1632                 break;
1633         default:
1634                 /*
1635                  * For SIMPLE and UNTAGGED Task Attribute commands
1636                  */
1637                 atomic_inc(&dev->simple_cmds);
1638                 smp_mb__after_atomic_inc();
1639                 break;
1640         }
1641
1642         if (atomic_read(&dev->dev_ordered_sync) == 0)
1643                 return false;
1644
1645         spin_lock(&dev->delayed_cmd_lock);
1646         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1647         spin_unlock(&dev->delayed_cmd_lock);
1648
1649         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1650                 " delayed CMD list, se_ordered_id: %u\n",
1651                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1652                 cmd->se_ordered_id);
1653         return true;
1654 }
1655
1656 void target_execute_cmd(struct se_cmd *cmd)
1657 {
1658         /*
1659          * If the received CDB has aleady been aborted stop processing it here.
1660          */
1661         if (transport_check_aborted_status(cmd, 1)) {
1662                 complete(&cmd->transport_lun_stop_comp);
1663                 return;
1664         }
1665
1666         /*
1667          * Determine if IOCTL context caller in requesting the stopping of this
1668          * command for LUN shutdown purposes.
1669          */
1670         spin_lock_irq(&cmd->t_state_lock);
1671         if (cmd->transport_state & CMD_T_LUN_STOP) {
1672                 pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
1673                         __func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
1674
1675                 cmd->transport_state &= ~CMD_T_ACTIVE;
1676                 spin_unlock_irq(&cmd->t_state_lock);
1677                 complete(&cmd->transport_lun_stop_comp);
1678                 return;
1679         }
1680         /*
1681          * Determine if frontend context caller is requesting the stopping of
1682          * this command for frontend exceptions.
1683          */
1684         if (cmd->transport_state & CMD_T_STOP) {
1685                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1686                         __func__, __LINE__,
1687                         cmd->se_tfo->get_task_tag(cmd));
1688
1689                 spin_unlock_irq(&cmd->t_state_lock);
1690                 complete(&cmd->t_transport_stop_comp);
1691                 return;
1692         }
1693
1694         cmd->t_state = TRANSPORT_PROCESSING;
1695         cmd->transport_state |= CMD_T_ACTIVE;
1696         spin_unlock_irq(&cmd->t_state_lock);
1697
1698         if (!target_handle_task_attr(cmd))
1699                 __target_execute_cmd(cmd);
1700 }
1701 EXPORT_SYMBOL(target_execute_cmd);
1702
1703 /*
1704  * Process all commands up to the last received ORDERED task attribute which
1705  * requires another blocking boundary
1706  */
1707 static void target_restart_delayed_cmds(struct se_device *dev)
1708 {
1709         for (;;) {
1710                 struct se_cmd *cmd;
1711
1712                 spin_lock(&dev->delayed_cmd_lock);
1713                 if (list_empty(&dev->delayed_cmd_list)) {
1714                         spin_unlock(&dev->delayed_cmd_lock);
1715                         break;
1716                 }
1717
1718                 cmd = list_entry(dev->delayed_cmd_list.next,
1719                                  struct se_cmd, se_delayed_node);
1720                 list_del(&cmd->se_delayed_node);
1721                 spin_unlock(&dev->delayed_cmd_lock);
1722
1723                 __target_execute_cmd(cmd);
1724
1725                 if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1726                         break;
1727         }
1728 }
1729
1730 /*
1731  * Called from I/O completion to determine which dormant/delayed
1732  * and ordered cmds need to have their tasks added to the execution queue.
1733  */
1734 static void transport_complete_task_attr(struct se_cmd *cmd)
1735 {
1736         struct se_device *dev = cmd->se_dev;
1737
1738         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1739                 return;
1740
1741         if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1742                 atomic_dec(&dev->simple_cmds);
1743                 smp_mb__after_atomic_dec();
1744                 dev->dev_cur_ordered_id++;
1745                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1746                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1747                         cmd->se_ordered_id);
1748         } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1749                 dev->dev_cur_ordered_id++;
1750                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1751                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1752                         cmd->se_ordered_id);
1753         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1754                 atomic_dec(&dev->dev_ordered_sync);
1755                 smp_mb__after_atomic_dec();
1756
1757                 dev->dev_cur_ordered_id++;
1758                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1759                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1760         }
1761
1762         target_restart_delayed_cmds(dev);
1763 }
1764
1765 static void transport_complete_qf(struct se_cmd *cmd)
1766 {
1767         int ret = 0;
1768
1769         transport_complete_task_attr(cmd);
1770
1771         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1772                 ret = cmd->se_tfo->queue_status(cmd);
1773                 if (ret)
1774                         goto out;
1775         }
1776
1777         switch (cmd->data_direction) {
1778         case DMA_FROM_DEVICE:
1779                 ret = cmd->se_tfo->queue_data_in(cmd);
1780                 break;
1781         case DMA_TO_DEVICE:
1782                 if (cmd->t_bidi_data_sg) {
1783                         ret = cmd->se_tfo->queue_data_in(cmd);
1784                         if (ret < 0)
1785                                 break;
1786                 }
1787                 /* Fall through for DMA_TO_DEVICE */
1788         case DMA_NONE:
1789                 ret = cmd->se_tfo->queue_status(cmd);
1790                 break;
1791         default:
1792                 break;
1793         }
1794
1795 out:
1796         if (ret < 0) {
1797                 transport_handle_queue_full(cmd, cmd->se_dev);
1798                 return;
1799         }
1800         transport_lun_remove_cmd(cmd);
1801         transport_cmd_check_stop_to_fabric(cmd);
1802 }
1803
1804 static void transport_handle_queue_full(
1805         struct se_cmd *cmd,
1806         struct se_device *dev)
1807 {
1808         spin_lock_irq(&dev->qf_cmd_lock);
1809         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1810         atomic_inc(&dev->dev_qf_count);
1811         smp_mb__after_atomic_inc();
1812         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1813
1814         schedule_work(&cmd->se_dev->qf_work_queue);
1815 }
1816
1817 static void target_complete_ok_work(struct work_struct *work)
1818 {
1819         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1820         int ret;
1821
1822         /*
1823          * Check if we need to move delayed/dormant tasks from cmds on the
1824          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1825          * Attribute.
1826          */
1827         transport_complete_task_attr(cmd);
1828
1829         /*
1830          * Check to schedule QUEUE_FULL work, or execute an existing
1831          * cmd->transport_qf_callback()
1832          */
1833         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1834                 schedule_work(&cmd->se_dev->qf_work_queue);
1835
1836         /*
1837          * Check if we need to send a sense buffer from
1838          * the struct se_cmd in question.
1839          */
1840         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1841                 WARN_ON(!cmd->scsi_status);
1842                 ret = transport_send_check_condition_and_sense(
1843                                         cmd, 0, 1);
1844                 if (ret == -EAGAIN || ret == -ENOMEM)
1845                         goto queue_full;
1846
1847                 transport_lun_remove_cmd(cmd);
1848                 transport_cmd_check_stop_to_fabric(cmd);
1849                 return;
1850         }
1851         /*
1852          * Check for a callback, used by amongst other things
1853          * XDWRITE_READ_10 emulation.
1854          */
1855         if (cmd->transport_complete_callback)
1856                 cmd->transport_complete_callback(cmd);
1857
1858         switch (cmd->data_direction) {
1859         case DMA_FROM_DEVICE:
1860                 spin_lock(&cmd->se_lun->lun_sep_lock);
1861                 if (cmd->se_lun->lun_sep) {
1862                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1863                                         cmd->data_length;
1864                 }
1865                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1866
1867                 ret = cmd->se_tfo->queue_data_in(cmd);
1868                 if (ret == -EAGAIN || ret == -ENOMEM)
1869                         goto queue_full;
1870                 break;
1871         case DMA_TO_DEVICE:
1872                 spin_lock(&cmd->se_lun->lun_sep_lock);
1873                 if (cmd->se_lun->lun_sep) {
1874                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
1875                                 cmd->data_length;
1876                 }
1877                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1878                 /*
1879                  * Check if we need to send READ payload for BIDI-COMMAND
1880                  */
1881                 if (cmd->t_bidi_data_sg) {
1882                         spin_lock(&cmd->se_lun->lun_sep_lock);
1883                         if (cmd->se_lun->lun_sep) {
1884                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1885                                         cmd->data_length;
1886                         }
1887                         spin_unlock(&cmd->se_lun->lun_sep_lock);
1888                         ret = cmd->se_tfo->queue_data_in(cmd);
1889                         if (ret == -EAGAIN || ret == -ENOMEM)
1890                                 goto queue_full;
1891                         break;
1892                 }
1893                 /* Fall through for DMA_TO_DEVICE */
1894         case DMA_NONE:
1895                 ret = cmd->se_tfo->queue_status(cmd);
1896                 if (ret == -EAGAIN || ret == -ENOMEM)
1897                         goto queue_full;
1898                 break;
1899         default:
1900                 break;
1901         }
1902
1903         transport_lun_remove_cmd(cmd);
1904         transport_cmd_check_stop_to_fabric(cmd);
1905         return;
1906
1907 queue_full:
1908         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
1909                 " data_direction: %d\n", cmd, cmd->data_direction);
1910         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1911         transport_handle_queue_full(cmd, cmd->se_dev);
1912 }
1913
1914 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
1915 {
1916         struct scatterlist *sg;
1917         int count;
1918
1919         for_each_sg(sgl, sg, nents, count)
1920                 __free_page(sg_page(sg));
1921
1922         kfree(sgl);
1923 }
1924
1925 static inline void transport_free_pages(struct se_cmd *cmd)
1926 {
1927         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
1928                 return;
1929
1930         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
1931         cmd->t_data_sg = NULL;
1932         cmd->t_data_nents = 0;
1933
1934         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
1935         cmd->t_bidi_data_sg = NULL;
1936         cmd->t_bidi_data_nents = 0;
1937 }
1938
1939 /**
1940  * transport_release_cmd - free a command
1941  * @cmd:       command to free
1942  *
1943  * This routine unconditionally frees a command, and reference counting
1944  * or list removal must be done in the caller.
1945  */
1946 static void transport_release_cmd(struct se_cmd *cmd)
1947 {
1948         BUG_ON(!cmd->se_tfo);
1949
1950         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1951                 core_tmr_release_req(cmd->se_tmr_req);
1952         if (cmd->t_task_cdb != cmd->__t_task_cdb)
1953                 kfree(cmd->t_task_cdb);
1954         /*
1955          * If this cmd has been setup with target_get_sess_cmd(), drop
1956          * the kref and call ->release_cmd() in kref callback.
1957          */
1958          if (cmd->check_release != 0) {
1959                 target_put_sess_cmd(cmd->se_sess, cmd);
1960                 return;
1961         }
1962         cmd->se_tfo->release_cmd(cmd);
1963 }
1964
1965 /**
1966  * transport_put_cmd - release a reference to a command
1967  * @cmd:       command to release
1968  *
1969  * This routine releases our reference to the command and frees it if possible.
1970  */
1971 static void transport_put_cmd(struct se_cmd *cmd)
1972 {
1973         unsigned long flags;
1974
1975         spin_lock_irqsave(&cmd->t_state_lock, flags);
1976         if (atomic_read(&cmd->t_fe_count) &&
1977             !atomic_dec_and_test(&cmd->t_fe_count)) {
1978                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1979                 return;
1980         }
1981
1982         if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
1983                 cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
1984                 target_remove_from_state_list(cmd);
1985         }
1986         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1987
1988         transport_free_pages(cmd);
1989         transport_release_cmd(cmd);
1990         return;
1991 }
1992
1993 void *transport_kmap_data_sg(struct se_cmd *cmd)
1994 {
1995         struct scatterlist *sg = cmd->t_data_sg;
1996         struct page **pages;
1997         int i;
1998
1999         /*
2000          * We need to take into account a possible offset here for fabrics like
2001          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2002          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2003          */
2004         if (!cmd->t_data_nents)
2005                 return NULL;
2006
2007         BUG_ON(!sg);
2008         if (cmd->t_data_nents == 1)
2009                 return kmap(sg_page(sg)) + sg->offset;
2010
2011         /* >1 page. use vmap */
2012         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2013         if (!pages)
2014                 return NULL;
2015
2016         /* convert sg[] to pages[] */
2017         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2018                 pages[i] = sg_page(sg);
2019         }
2020
2021         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2022         kfree(pages);
2023         if (!cmd->t_data_vmap)
2024                 return NULL;
2025
2026         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2027 }
2028 EXPORT_SYMBOL(transport_kmap_data_sg);
2029
2030 void transport_kunmap_data_sg(struct se_cmd *cmd)
2031 {
2032         if (!cmd->t_data_nents) {
2033                 return;
2034         } else if (cmd->t_data_nents == 1) {
2035                 kunmap(sg_page(cmd->t_data_sg));
2036                 return;
2037         }
2038
2039         vunmap(cmd->t_data_vmap);
2040         cmd->t_data_vmap = NULL;
2041 }
2042 EXPORT_SYMBOL(transport_kunmap_data_sg);
2043
2044 static int
2045 transport_generic_get_mem(struct se_cmd *cmd)
2046 {
2047         u32 length = cmd->data_length;
2048         unsigned int nents;
2049         struct page *page;
2050         gfp_t zero_flag;
2051         int i = 0;
2052
2053         nents = DIV_ROUND_UP(length, PAGE_SIZE);
2054         cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
2055         if (!cmd->t_data_sg)
2056                 return -ENOMEM;
2057
2058         cmd->t_data_nents = nents;
2059         sg_init_table(cmd->t_data_sg, nents);
2060
2061         zero_flag = cmd->se_cmd_flags & SCF_SCSI_DATA_CDB ? 0 : __GFP_ZERO;
2062
2063         while (length) {
2064                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2065                 page = alloc_page(GFP_KERNEL | zero_flag);
2066                 if (!page)
2067                         goto out;
2068
2069                 sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
2070                 length -= page_len;
2071                 i++;
2072         }
2073         return 0;
2074
2075 out:
2076         while (i > 0) {
2077                 i--;
2078                 __free_page(sg_page(&cmd->t_data_sg[i]));
2079         }
2080         kfree(cmd->t_data_sg);
2081         cmd->t_data_sg = NULL;
2082         return -ENOMEM;
2083 }
2084
2085 /*
2086  * Allocate any required resources to execute the command.  For writes we
2087  * might not have the payload yet, so notify the fabric via a call to
2088  * ->write_pending instead. Otherwise place it on the execution queue.
2089  */
2090 sense_reason_t
2091 transport_generic_new_cmd(struct se_cmd *cmd)
2092 {
2093         int ret = 0;
2094
2095         /*
2096          * Determine is the TCM fabric module has already allocated physical
2097          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2098          * beforehand.
2099          */
2100         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2101             cmd->data_length) {
2102                 ret = transport_generic_get_mem(cmd);
2103                 if (ret < 0)
2104                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2105         }
2106
2107         atomic_inc(&cmd->t_fe_count);
2108
2109         /*
2110          * If this command is not a write we can execute it right here,
2111          * for write buffers we need to notify the fabric driver first
2112          * and let it call back once the write buffers are ready.
2113          */
2114         target_add_to_state_list(cmd);
2115         if (cmd->data_direction != DMA_TO_DEVICE) {
2116                 target_execute_cmd(cmd);
2117                 return 0;
2118         }
2119
2120         spin_lock_irq(&cmd->t_state_lock);
2121         cmd->t_state = TRANSPORT_WRITE_PENDING;
2122         spin_unlock_irq(&cmd->t_state_lock);
2123
2124         transport_cmd_check_stop(cmd, false);
2125
2126         ret = cmd->se_tfo->write_pending(cmd);
2127         if (ret == -EAGAIN || ret == -ENOMEM)
2128                 goto queue_full;
2129
2130         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2131         WARN_ON(ret);
2132
2133         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2134
2135 queue_full:
2136         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2137         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2138         transport_handle_queue_full(cmd, cmd->se_dev);
2139         return 0;
2140 }
2141 EXPORT_SYMBOL(transport_generic_new_cmd);
2142
2143 static void transport_write_pending_qf(struct se_cmd *cmd)
2144 {
2145         int ret;
2146
2147         ret = cmd->se_tfo->write_pending(cmd);
2148         if (ret == -EAGAIN || ret == -ENOMEM) {
2149                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2150                          cmd);
2151                 transport_handle_queue_full(cmd, cmd->se_dev);
2152         }
2153 }
2154
2155 void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2156 {
2157         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2158                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2159                          transport_wait_for_tasks(cmd);
2160
2161                 transport_release_cmd(cmd);
2162         } else {
2163                 if (wait_for_tasks)
2164                         transport_wait_for_tasks(cmd);
2165
2166                 core_dec_lacl_count(cmd->se_sess->se_node_acl, cmd);
2167
2168                 if (cmd->se_lun)
2169                         transport_lun_remove_cmd(cmd);
2170
2171                 transport_put_cmd(cmd);
2172         }
2173 }
2174 EXPORT_SYMBOL(transport_generic_free_cmd);
2175
2176 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2177  * @se_sess:    session to reference
2178  * @se_cmd:     command descriptor to add
2179  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2180  */
2181 int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2182                                bool ack_kref)
2183 {
2184         unsigned long flags;
2185         int ret = 0;
2186
2187         kref_init(&se_cmd->cmd_kref);
2188         /*
2189          * Add a second kref if the fabric caller is expecting to handle
2190          * fabric acknowledgement that requires two target_put_sess_cmd()
2191          * invocations before se_cmd descriptor release.
2192          */
2193         if (ack_kref == true) {
2194                 kref_get(&se_cmd->cmd_kref);
2195                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2196         }
2197
2198         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2199         if (se_sess->sess_tearing_down) {
2200                 ret = -ESHUTDOWN;
2201                 goto out;
2202         }
2203         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2204         se_cmd->check_release = 1;
2205
2206 out:
2207         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2208         return ret;
2209 }
2210 EXPORT_SYMBOL(target_get_sess_cmd);
2211
2212 static void target_release_cmd_kref(struct kref *kref)
2213 {
2214         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2215         struct se_session *se_sess = se_cmd->se_sess;
2216         unsigned long flags;
2217
2218         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2219         if (list_empty(&se_cmd->se_cmd_list)) {
2220                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2221                 se_cmd->se_tfo->release_cmd(se_cmd);
2222                 return;
2223         }
2224         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2225                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2226                 complete(&se_cmd->cmd_wait_comp);
2227                 return;
2228         }
2229         list_del(&se_cmd->se_cmd_list);
2230         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2231
2232         se_cmd->se_tfo->release_cmd(se_cmd);
2233 }
2234
2235 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2236  * @se_sess:    session to reference
2237  * @se_cmd:     command descriptor to drop
2238  */
2239 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2240 {
2241         return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2242 }
2243 EXPORT_SYMBOL(target_put_sess_cmd);
2244
2245 /* target_sess_cmd_list_set_waiting - Flag all commands in
2246  *         sess_cmd_list to complete cmd_wait_comp.  Set
2247  *         sess_tearing_down so no more commands are queued.
2248  * @se_sess:    session to flag
2249  */
2250 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2251 {
2252         struct se_cmd *se_cmd;
2253         unsigned long flags;
2254
2255         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2256
2257         WARN_ON(se_sess->sess_tearing_down);
2258         se_sess->sess_tearing_down = 1;
2259
2260         list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list)
2261                 se_cmd->cmd_wait_set = 1;
2262
2263         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2264 }
2265 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2266
2267 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2268  * @se_sess:    session to wait for active I/O
2269  * @wait_for_tasks:     Make extra transport_wait_for_tasks call
2270  */
2271 void target_wait_for_sess_cmds(
2272         struct se_session *se_sess,
2273         int wait_for_tasks)
2274 {
2275         struct se_cmd *se_cmd, *tmp_cmd;
2276         bool rc = false;
2277
2278         list_for_each_entry_safe(se_cmd, tmp_cmd,
2279                                 &se_sess->sess_cmd_list, se_cmd_list) {
2280                 list_del(&se_cmd->se_cmd_list);
2281
2282                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2283                         " %d\n", se_cmd, se_cmd->t_state,
2284                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2285
2286                 if (wait_for_tasks) {
2287                         pr_debug("Calling transport_wait_for_tasks se_cmd: %p t_state: %d,"
2288                                 " fabric state: %d\n", se_cmd, se_cmd->t_state,
2289                                 se_cmd->se_tfo->get_cmd_state(se_cmd));
2290
2291                         rc = transport_wait_for_tasks(se_cmd);
2292
2293                         pr_debug("After transport_wait_for_tasks se_cmd: %p t_state: %d,"
2294                                 " fabric state: %d\n", se_cmd, se_cmd->t_state,
2295                                 se_cmd->se_tfo->get_cmd_state(se_cmd));
2296                 }
2297
2298                 if (!rc) {
2299                         wait_for_completion(&se_cmd->cmd_wait_comp);
2300                         pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2301                                 " fabric state: %d\n", se_cmd, se_cmd->t_state,
2302                                 se_cmd->se_tfo->get_cmd_state(se_cmd));
2303                 }
2304
2305                 se_cmd->se_tfo->release_cmd(se_cmd);
2306         }
2307 }
2308 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2309
2310 /*      transport_lun_wait_for_tasks():
2311  *
2312  *      Called from ConfigFS context to stop the passed struct se_cmd to allow
2313  *      an struct se_lun to be successfully shutdown.
2314  */
2315 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
2316 {
2317         unsigned long flags;
2318         int ret = 0;
2319
2320         /*
2321          * If the frontend has already requested this struct se_cmd to
2322          * be stopped, we can safely ignore this struct se_cmd.
2323          */
2324         spin_lock_irqsave(&cmd->t_state_lock, flags);
2325         if (cmd->transport_state & CMD_T_STOP) {
2326                 cmd->transport_state &= ~CMD_T_LUN_STOP;
2327
2328                 pr_debug("ConfigFS ITT[0x%08x] - CMD_T_STOP, skipping\n",
2329                          cmd->se_tfo->get_task_tag(cmd));
2330                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2331                 transport_cmd_check_stop(cmd, false);
2332                 return -EPERM;
2333         }
2334         cmd->transport_state |= CMD_T_LUN_FE_STOP;
2335         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2336
2337         // XXX: audit task_flags checks.
2338         spin_lock_irqsave(&cmd->t_state_lock, flags);
2339         if ((cmd->transport_state & CMD_T_BUSY) &&
2340             (cmd->transport_state & CMD_T_SENT)) {
2341                 if (!target_stop_cmd(cmd, &flags))
2342                         ret++;
2343         }
2344         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2345
2346         pr_debug("ConfigFS: cmd: %p stop tasks ret:"
2347                         " %d\n", cmd, ret);
2348         if (!ret) {
2349                 pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
2350                                 cmd->se_tfo->get_task_tag(cmd));
2351                 wait_for_completion(&cmd->transport_lun_stop_comp);
2352                 pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
2353                                 cmd->se_tfo->get_task_tag(cmd));
2354         }
2355
2356         return 0;
2357 }
2358
2359 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
2360 {
2361         struct se_cmd *cmd = NULL;
2362         unsigned long lun_flags, cmd_flags;
2363         /*
2364          * Do exception processing and return CHECK_CONDITION status to the
2365          * Initiator Port.
2366          */
2367         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2368         while (!list_empty(&lun->lun_cmd_list)) {
2369                 cmd = list_first_entry(&lun->lun_cmd_list,
2370                        struct se_cmd, se_lun_node);
2371                 list_del_init(&cmd->se_lun_node);
2372
2373                 spin_lock(&cmd->t_state_lock);
2374                 pr_debug("SE_LUN[%d] - Setting cmd->transport"
2375                         "_lun_stop for  ITT: 0x%08x\n",
2376                         cmd->se_lun->unpacked_lun,
2377                         cmd->se_tfo->get_task_tag(cmd));
2378                 cmd->transport_state |= CMD_T_LUN_STOP;
2379                 spin_unlock(&cmd->t_state_lock);
2380
2381                 spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2382
2383                 if (!cmd->se_lun) {
2384                         pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
2385                                 cmd->se_tfo->get_task_tag(cmd),
2386                                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2387                         BUG();
2388                 }
2389                 /*
2390                  * If the Storage engine still owns the iscsi_cmd_t, determine
2391                  * and/or stop its context.
2392                  */
2393                 pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
2394                         "_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
2395                         cmd->se_tfo->get_task_tag(cmd));
2396
2397                 if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
2398                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2399                         continue;
2400                 }
2401
2402                 pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
2403                         "_wait_for_tasks(): SUCCESS\n",
2404                         cmd->se_lun->unpacked_lun,
2405                         cmd->se_tfo->get_task_tag(cmd));
2406
2407                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2408                 if (!(cmd->transport_state & CMD_T_DEV_ACTIVE)) {
2409                         spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2410                         goto check_cond;
2411                 }
2412                 cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
2413                 target_remove_from_state_list(cmd);
2414                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2415
2416                 /*
2417                  * The Storage engine stopped this struct se_cmd before it was
2418                  * send to the fabric frontend for delivery back to the
2419                  * Initiator Node.  Return this SCSI CDB back with an
2420                  * CHECK_CONDITION status.
2421                  */
2422 check_cond:
2423                 transport_send_check_condition_and_sense(cmd,
2424                                 TCM_NON_EXISTENT_LUN, 0);
2425                 /*
2426                  *  If the fabric frontend is waiting for this iscsi_cmd_t to
2427                  * be released, notify the waiting thread now that LU has
2428                  * finished accessing it.
2429                  */
2430                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2431                 if (cmd->transport_state & CMD_T_LUN_FE_STOP) {
2432                         pr_debug("SE_LUN[%d] - Detected FE stop for"
2433                                 " struct se_cmd: %p ITT: 0x%08x\n",
2434                                 lun->unpacked_lun,
2435                                 cmd, cmd->se_tfo->get_task_tag(cmd));
2436
2437                         spin_unlock_irqrestore(&cmd->t_state_lock,
2438                                         cmd_flags);
2439                         transport_cmd_check_stop(cmd, false);
2440                         complete(&cmd->transport_lun_fe_stop_comp);
2441                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2442                         continue;
2443                 }
2444                 pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
2445                         lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
2446
2447                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2448                 spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2449         }
2450         spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2451 }
2452
2453 static int transport_clear_lun_thread(void *p)
2454 {
2455         struct se_lun *lun = p;
2456
2457         __transport_clear_lun_from_sessions(lun);
2458         complete(&lun->lun_shutdown_comp);
2459
2460         return 0;
2461 }
2462
2463 int transport_clear_lun_from_sessions(struct se_lun *lun)
2464 {
2465         struct task_struct *kt;
2466
2467         kt = kthread_run(transport_clear_lun_thread, lun,
2468                         "tcm_cl_%u", lun->unpacked_lun);
2469         if (IS_ERR(kt)) {
2470                 pr_err("Unable to start clear_lun thread\n");
2471                 return PTR_ERR(kt);
2472         }
2473         wait_for_completion(&lun->lun_shutdown_comp);
2474
2475         return 0;
2476 }
2477
2478 /**
2479  * transport_wait_for_tasks - wait for completion to occur
2480  * @cmd:        command to wait
2481  *
2482  * Called from frontend fabric context to wait for storage engine
2483  * to pause and/or release frontend generated struct se_cmd.
2484  */
2485 bool transport_wait_for_tasks(struct se_cmd *cmd)
2486 {
2487         unsigned long flags;
2488
2489         spin_lock_irqsave(&cmd->t_state_lock, flags);
2490         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2491             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2492                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2493                 return false;
2494         }
2495
2496         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2497             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2498                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2499                 return false;
2500         }
2501         /*
2502          * If we are already stopped due to an external event (ie: LUN shutdown)
2503          * sleep until the connection can have the passed struct se_cmd back.
2504          * The cmd->transport_lun_stopped_sem will be upped by
2505          * transport_clear_lun_from_sessions() once the ConfigFS context caller
2506          * has completed its operation on the struct se_cmd.
2507          */
2508         if (cmd->transport_state & CMD_T_LUN_STOP) {
2509                 pr_debug("wait_for_tasks: Stopping"
2510                         " wait_for_completion(&cmd->t_tasktransport_lun_fe"
2511                         "_stop_comp); for ITT: 0x%08x\n",
2512                         cmd->se_tfo->get_task_tag(cmd));
2513                 /*
2514                  * There is a special case for WRITES where a FE exception +
2515                  * LUN shutdown means ConfigFS context is still sleeping on
2516                  * transport_lun_stop_comp in transport_lun_wait_for_tasks().
2517                  * We go ahead and up transport_lun_stop_comp just to be sure
2518                  * here.
2519                  */
2520                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2521                 complete(&cmd->transport_lun_stop_comp);
2522                 wait_for_completion(&cmd->transport_lun_fe_stop_comp);
2523                 spin_lock_irqsave(&cmd->t_state_lock, flags);
2524
2525                 target_remove_from_state_list(cmd);
2526                 /*
2527                  * At this point, the frontend who was the originator of this
2528                  * struct se_cmd, now owns the structure and can be released through
2529                  * normal means below.
2530                  */
2531                 pr_debug("wait_for_tasks: Stopped"
2532                         " wait_for_completion(&cmd->t_tasktransport_lun_fe_"
2533                         "stop_comp); for ITT: 0x%08x\n",
2534                         cmd->se_tfo->get_task_tag(cmd));
2535
2536                 cmd->transport_state &= ~CMD_T_LUN_STOP;
2537         }
2538
2539         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2540                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2541                 return false;
2542         }
2543
2544         cmd->transport_state |= CMD_T_STOP;
2545
2546         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2547                 " i_state: %d, t_state: %d, CMD_T_STOP\n",
2548                 cmd, cmd->se_tfo->get_task_tag(cmd),
2549                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2550
2551         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2552
2553         wait_for_completion(&cmd->t_transport_stop_comp);
2554
2555         spin_lock_irqsave(&cmd->t_state_lock, flags);
2556         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2557
2558         pr_debug("wait_for_tasks: Stopped wait_for_completion("
2559                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2560                 cmd->se_tfo->get_task_tag(cmd));
2561
2562         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2563
2564         return true;
2565 }
2566 EXPORT_SYMBOL(transport_wait_for_tasks);
2567
2568 static int transport_get_sense_codes(
2569         struct se_cmd *cmd,
2570         u8 *asc,
2571         u8 *ascq)
2572 {
2573         *asc = cmd->scsi_asc;
2574         *ascq = cmd->scsi_ascq;
2575
2576         return 0;
2577 }
2578
2579 int
2580 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2581                 sense_reason_t reason, int from_transport)
2582 {
2583         unsigned char *buffer = cmd->sense_buffer;
2584         unsigned long flags;
2585         u8 asc = 0, ascq = 0;
2586
2587         spin_lock_irqsave(&cmd->t_state_lock, flags);
2588         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2589                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2590                 return 0;
2591         }
2592         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2593         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2594
2595         if (!reason && from_transport)
2596                 goto after_reason;
2597
2598         if (!from_transport)
2599                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2600
2601         /*
2602          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2603          * SENSE KEY values from include/scsi/scsi.h
2604          */
2605         switch (reason) {
2606         case TCM_NO_SENSE:
2607                 /* CURRENT ERROR */
2608                 buffer[0] = 0x70;
2609                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2610                 /* Not Ready */
2611                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2612                 /* NO ADDITIONAL SENSE INFORMATION */
2613                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2614                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2615                 break;
2616         case TCM_NON_EXISTENT_LUN:
2617                 /* CURRENT ERROR */
2618                 buffer[0] = 0x70;
2619                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2620                 /* ILLEGAL REQUEST */
2621                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2622                 /* LOGICAL UNIT NOT SUPPORTED */
2623                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2624                 break;
2625         case TCM_UNSUPPORTED_SCSI_OPCODE:
2626         case TCM_SECTOR_COUNT_TOO_MANY:
2627                 /* CURRENT ERROR */
2628                 buffer[0] = 0x70;
2629                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2630                 /* ILLEGAL REQUEST */
2631                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2632                 /* INVALID COMMAND OPERATION CODE */
2633                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2634                 break;
2635         case TCM_UNKNOWN_MODE_PAGE:
2636                 /* CURRENT ERROR */
2637                 buffer[0] = 0x70;
2638                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2639                 /* ILLEGAL REQUEST */
2640                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2641                 /* INVALID FIELD IN CDB */
2642                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2643                 break;
2644         case TCM_CHECK_CONDITION_ABORT_CMD:
2645                 /* CURRENT ERROR */
2646                 buffer[0] = 0x70;
2647                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2648                 /* ABORTED COMMAND */
2649                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2650                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2651                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2652                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2653                 break;
2654         case TCM_INCORRECT_AMOUNT_OF_DATA:
2655                 /* CURRENT ERROR */
2656                 buffer[0] = 0x70;
2657                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2658                 /* ABORTED COMMAND */
2659                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2660                 /* WRITE ERROR */
2661                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2662                 /* NOT ENOUGH UNSOLICITED DATA */
2663                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2664                 break;
2665         case TCM_INVALID_CDB_FIELD:
2666                 /* CURRENT ERROR */
2667                 buffer[0] = 0x70;
2668                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2669                 /* ILLEGAL REQUEST */
2670                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2671                 /* INVALID FIELD IN CDB */
2672                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2673                 break;
2674         case TCM_INVALID_PARAMETER_LIST:
2675                 /* CURRENT ERROR */
2676                 buffer[0] = 0x70;
2677                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2678                 /* ILLEGAL REQUEST */
2679                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2680                 /* INVALID FIELD IN PARAMETER LIST */
2681                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2682                 break;
2683         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2684                 /* CURRENT ERROR */
2685                 buffer[0] = 0x70;
2686                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2687                 /* ILLEGAL REQUEST */
2688                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2689                 /* PARAMETER LIST LENGTH ERROR */
2690                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2691                 break;
2692         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2693                 /* CURRENT ERROR */
2694                 buffer[0] = 0x70;
2695                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2696                 /* ABORTED COMMAND */
2697                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2698                 /* WRITE ERROR */
2699                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2700                 /* UNEXPECTED_UNSOLICITED_DATA */
2701                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2702                 break;
2703         case TCM_SERVICE_CRC_ERROR:
2704                 /* CURRENT ERROR */
2705                 buffer[0] = 0x70;
2706                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2707                 /* ABORTED COMMAND */
2708                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2709                 /* PROTOCOL SERVICE CRC ERROR */
2710                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2711                 /* N/A */
2712                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2713                 break;
2714         case TCM_SNACK_REJECTED:
2715                 /* CURRENT ERROR */
2716                 buffer[0] = 0x70;
2717                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2718                 /* ABORTED COMMAND */
2719                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2720                 /* READ ERROR */
2721                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2722                 /* FAILED RETRANSMISSION REQUEST */
2723                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2724                 break;
2725         case TCM_WRITE_PROTECTED:
2726                 /* CURRENT ERROR */
2727                 buffer[0] = 0x70;
2728                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2729                 /* DATA PROTECT */
2730                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2731                 /* WRITE PROTECTED */
2732                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2733                 break;
2734         case TCM_ADDRESS_OUT_OF_RANGE:
2735                 /* CURRENT ERROR */
2736                 buffer[0] = 0x70;
2737                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2738                 /* ILLEGAL REQUEST */
2739                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2740                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2741                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2742                 break;
2743         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2744                 /* CURRENT ERROR */
2745                 buffer[0] = 0x70;
2746                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2747                 /* UNIT ATTENTION */
2748                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2749                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2750                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2751                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2752                 break;
2753         case TCM_CHECK_CONDITION_NOT_READY:
2754                 /* CURRENT ERROR */
2755                 buffer[0] = 0x70;
2756                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2757                 /* Not Ready */
2758                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2759                 transport_get_sense_codes(cmd, &asc, &ascq);
2760                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2761                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2762                 break;
2763         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2764         default:
2765                 /* CURRENT ERROR */
2766                 buffer[0] = 0x70;
2767                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2768                 /*
2769                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2770                  * Solaris initiators.  Returning NOT READY instead means the
2771                  * operations will be retried a finite number of times and we
2772                  * can survive intermittent errors.
2773                  */
2774                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2775                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2776                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2777                 break;
2778         }
2779         /*
2780          * This code uses linux/include/scsi/scsi.h SAM status codes!
2781          */
2782         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2783         /*
2784          * Automatically padded, this value is encoded in the fabric's
2785          * data_length response PDU containing the SCSI defined sense data.
2786          */
2787         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2788
2789 after_reason:
2790         return cmd->se_tfo->queue_status(cmd);
2791 }
2792 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2793
2794 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2795 {
2796         if (!(cmd->transport_state & CMD_T_ABORTED))
2797                 return 0;
2798
2799         if (!send_status || (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
2800                 return 1;
2801
2802         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2803                  cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2804
2805         cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
2806         cmd->se_tfo->queue_status(cmd);
2807
2808         return 1;
2809 }
2810 EXPORT_SYMBOL(transport_check_aborted_status);
2811
2812 void transport_send_task_abort(struct se_cmd *cmd)
2813 {
2814         unsigned long flags;
2815
2816         spin_lock_irqsave(&cmd->t_state_lock, flags);
2817         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION | SCF_SENT_DELAYED_TAS)) {
2818                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2819                 return;
2820         }
2821         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2822
2823         /*
2824          * If there are still expected incoming fabric WRITEs, we wait
2825          * until until they have completed before sending a TASK_ABORTED
2826          * response.  This response with TASK_ABORTED status will be
2827          * queued back to fabric module by transport_check_aborted_status().
2828          */
2829         if (cmd->data_direction == DMA_TO_DEVICE) {
2830                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2831                         cmd->transport_state |= CMD_T_ABORTED;
2832                         smp_mb__after_atomic_inc();
2833                 }
2834         }
2835         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2836
2837         transport_lun_remove_cmd(cmd);
2838
2839         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2840                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
2841                 cmd->se_tfo->get_task_tag(cmd));
2842
2843         cmd->se_tfo->queue_status(cmd);
2844 }
2845
2846 static void target_tmr_work(struct work_struct *work)
2847 {
2848         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2849         struct se_device *dev = cmd->se_dev;
2850         struct se_tmr_req *tmr = cmd->se_tmr_req;
2851         int ret;
2852
2853         switch (tmr->function) {
2854         case TMR_ABORT_TASK:
2855                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2856                 break;
2857         case TMR_ABORT_TASK_SET:
2858         case TMR_CLEAR_ACA:
2859         case TMR_CLEAR_TASK_SET:
2860                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2861                 break;
2862         case TMR_LUN_RESET:
2863                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2864                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2865                                          TMR_FUNCTION_REJECTED;
2866                 break;
2867         case TMR_TARGET_WARM_RESET:
2868                 tmr->response = TMR_FUNCTION_REJECTED;
2869                 break;
2870         case TMR_TARGET_COLD_RESET:
2871                 tmr->response = TMR_FUNCTION_REJECTED;
2872                 break;
2873         default:
2874                 pr_err("Uknown TMR function: 0x%02x.\n",
2875                                 tmr->function);
2876                 tmr->response = TMR_FUNCTION_REJECTED;
2877                 break;
2878         }
2879
2880         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2881         cmd->se_tfo->queue_tm_rsp(cmd);
2882
2883         transport_cmd_check_stop_to_fabric(cmd);
2884 }
2885
2886 int transport_generic_handle_tmr(
2887         struct se_cmd *cmd)
2888 {
2889         INIT_WORK(&cmd->work, target_tmr_work);
2890         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2891         return 0;
2892 }
2893 EXPORT_SYMBOL(transport_generic_handle_tmr);