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