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                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1144                 return ret;
1145         }
1146
1147         ret = dev->transport->parse_cdb(cmd);
1148         if (ret)
1149                 return ret;
1150
1151         ret = transport_check_alloc_task_attr(cmd);
1152         if (ret)
1153                 return ret;
1154
1155         spin_lock_irqsave(&cmd->t_state_lock, flags);
1156         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1157         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1158
1159         spin_lock(&cmd->se_lun->lun_sep_lock);
1160         if (cmd->se_lun->lun_sep)
1161                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1162         spin_unlock(&cmd->se_lun->lun_sep_lock);
1163         return 0;
1164 }
1165 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1166
1167 /*
1168  * Used by fabric module frontends to queue tasks directly.
1169  * Many only be used from process context only
1170  */
1171 int transport_handle_cdb_direct(
1172         struct se_cmd *cmd)
1173 {
1174         sense_reason_t ret;
1175
1176         if (!cmd->se_lun) {
1177                 dump_stack();
1178                 pr_err("cmd->se_lun is NULL\n");
1179                 return -EINVAL;
1180         }
1181         if (in_interrupt()) {
1182                 dump_stack();
1183                 pr_err("transport_generic_handle_cdb cannot be called"
1184                                 " from interrupt context\n");
1185                 return -EINVAL;
1186         }
1187         /*
1188          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1189          * outstanding descriptors are handled correctly during shutdown via
1190          * transport_wait_for_tasks()
1191          *
1192          * Also, we don't take cmd->t_state_lock here as we only expect
1193          * this to be called for initial descriptor submission.
1194          */
1195         cmd->t_state = TRANSPORT_NEW_CMD;
1196         cmd->transport_state |= CMD_T_ACTIVE;
1197
1198         /*
1199          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1200          * so follow TRANSPORT_NEW_CMD processing thread context usage
1201          * and call transport_generic_request_failure() if necessary..
1202          */
1203         ret = transport_generic_new_cmd(cmd);
1204         if (ret)
1205                 transport_generic_request_failure(cmd, ret);
1206         return 0;
1207 }
1208 EXPORT_SYMBOL(transport_handle_cdb_direct);
1209
1210 static sense_reason_t
1211 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1212                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1213 {
1214         if (!sgl || !sgl_count)
1215                 return 0;
1216
1217         /*
1218          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1219          * scatterlists already have been set to follow what the fabric
1220          * passes for the original expected data transfer length.
1221          */
1222         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1223                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1224                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1225                 return TCM_INVALID_CDB_FIELD;
1226         }
1227
1228         cmd->t_data_sg = sgl;
1229         cmd->t_data_nents = sgl_count;
1230
1231         if (sgl_bidi && sgl_bidi_count) {
1232                 cmd->t_bidi_data_sg = sgl_bidi;
1233                 cmd->t_bidi_data_nents = sgl_bidi_count;
1234         }
1235         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1236         return 0;
1237 }
1238
1239 /*
1240  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1241  *                       se_cmd + use pre-allocated SGL memory.
1242  *
1243  * @se_cmd: command descriptor to submit
1244  * @se_sess: associated se_sess for endpoint
1245  * @cdb: pointer to SCSI CDB
1246  * @sense: pointer to SCSI sense buffer
1247  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1248  * @data_length: fabric expected data transfer length
1249  * @task_addr: SAM task attribute
1250  * @data_dir: DMA data direction
1251  * @flags: flags for command submission from target_sc_flags_tables
1252  * @sgl: struct scatterlist memory for unidirectional mapping
1253  * @sgl_count: scatterlist count for unidirectional mapping
1254  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1255  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1256  *
1257  * Returns non zero to signal active I/O shutdown failure.  All other
1258  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1259  * but still return zero here.
1260  *
1261  * This may only be called from process context, and also currently
1262  * assumes internal allocation of fabric payload buffer by target-core.
1263  */
1264 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1265                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1266                 u32 data_length, int task_attr, int data_dir, int flags,
1267                 struct scatterlist *sgl, u32 sgl_count,
1268                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1269 {
1270         struct se_portal_group *se_tpg;
1271         sense_reason_t rc;
1272         int ret;
1273
1274         se_tpg = se_sess->se_tpg;
1275         BUG_ON(!se_tpg);
1276         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1277         BUG_ON(in_interrupt());
1278         /*
1279          * Initialize se_cmd for target operation.  From this point
1280          * exceptions are handled by sending exception status via
1281          * target_core_fabric_ops->queue_status() callback
1282          */
1283         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1284                                 data_length, data_dir, task_attr, sense);
1285         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1286                 se_cmd->unknown_data_length = 1;
1287         /*
1288          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1289          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1290          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1291          * kref_put() to happen during fabric packet acknowledgement.
1292          */
1293         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1294         if (ret)
1295                 return ret;
1296         /*
1297          * Signal bidirectional data payloads to target-core
1298          */
1299         if (flags & TARGET_SCF_BIDI_OP)
1300                 se_cmd->se_cmd_flags |= SCF_BIDI;
1301         /*
1302          * Locate se_lun pointer and attach it to struct se_cmd
1303          */
1304         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1305         if (rc) {
1306                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1307                 target_put_sess_cmd(se_sess, se_cmd);
1308                 return 0;
1309         }
1310
1311         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1312         if (rc != 0) {
1313                 transport_generic_request_failure(se_cmd, rc);
1314                 return 0;
1315         }
1316         /*
1317          * When a non zero sgl_count has been passed perform SGL passthrough
1318          * mapping for pre-allocated fabric memory instead of having target
1319          * core perform an internal SGL allocation..
1320          */
1321         if (sgl_count != 0) {
1322                 BUG_ON(!sgl);
1323
1324                 /*
1325                  * A work-around for tcm_loop as some userspace code via
1326                  * scsi-generic do not memset their associated read buffers,
1327                  * so go ahead and do that here for type non-data CDBs.  Also
1328                  * note that this is currently guaranteed to be a single SGL
1329                  * for this case by target core in target_setup_cmd_from_cdb()
1330                  * -> transport_generic_cmd_sequencer().
1331                  */
1332                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1333                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1334                         unsigned char *buf = NULL;
1335
1336                         if (sgl)
1337                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1338
1339                         if (buf) {
1340                                 memset(buf, 0, sgl->length);
1341                                 kunmap(sg_page(sgl));
1342                         }
1343                 }
1344
1345                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1346                                 sgl_bidi, sgl_bidi_count);
1347                 if (rc != 0) {
1348                         transport_generic_request_failure(se_cmd, rc);
1349                         return 0;
1350                 }
1351         }
1352         /*
1353          * Check if we need to delay processing because of ALUA
1354          * Active/NonOptimized primary access state..
1355          */
1356         core_alua_check_nonop_delay(se_cmd);
1357
1358         transport_handle_cdb_direct(se_cmd);
1359         return 0;
1360 }
1361 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1362
1363 /*
1364  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1365  *
1366  * @se_cmd: command descriptor to submit
1367  * @se_sess: associated se_sess for endpoint
1368  * @cdb: pointer to SCSI CDB
1369  * @sense: pointer to SCSI sense buffer
1370  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1371  * @data_length: fabric expected data transfer length
1372  * @task_addr: SAM task attribute
1373  * @data_dir: DMA data direction
1374  * @flags: flags for command submission from target_sc_flags_tables
1375  *
1376  * Returns non zero to signal active I/O shutdown failure.  All other
1377  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1378  * but still return zero here.
1379  *
1380  * This may only be called from process context, and also currently
1381  * assumes internal allocation of fabric payload buffer by target-core.
1382  *
1383  * It also assumes interal target core SGL memory allocation.
1384  */
1385 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1386                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1387                 u32 data_length, int task_attr, int data_dir, int flags)
1388 {
1389         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1390                         unpacked_lun, data_length, task_attr, data_dir,
1391                         flags, NULL, 0, NULL, 0);
1392 }
1393 EXPORT_SYMBOL(target_submit_cmd);
1394
1395 static void target_complete_tmr_failure(struct work_struct *work)
1396 {
1397         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1398
1399         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1400         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1401
1402         transport_cmd_check_stop_to_fabric(se_cmd);
1403 }
1404
1405 /**
1406  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1407  *                     for TMR CDBs
1408  *
1409  * @se_cmd: command descriptor to submit
1410  * @se_sess: associated se_sess for endpoint
1411  * @sense: pointer to SCSI sense buffer
1412  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1413  * @fabric_context: fabric context for TMR req
1414  * @tm_type: Type of TM request
1415  * @gfp: gfp type for caller
1416  * @tag: referenced task tag for TMR_ABORT_TASK
1417  * @flags: submit cmd flags
1418  *
1419  * Callable from all contexts.
1420  **/
1421
1422 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1423                 unsigned char *sense, u32 unpacked_lun,
1424                 void *fabric_tmr_ptr, unsigned char tm_type,
1425                 gfp_t gfp, unsigned int tag, int flags)
1426 {
1427         struct se_portal_group *se_tpg;
1428         int ret;
1429
1430         se_tpg = se_sess->se_tpg;
1431         BUG_ON(!se_tpg);
1432
1433         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1434                               0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1435         /*
1436          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1437          * allocation failure.
1438          */
1439         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1440         if (ret < 0)
1441                 return -ENOMEM;
1442
1443         if (tm_type == TMR_ABORT_TASK)
1444                 se_cmd->se_tmr_req->ref_task_tag = tag;
1445
1446         /* See target_submit_cmd for commentary */
1447         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1448         if (ret) {
1449                 core_tmr_release_req(se_cmd->se_tmr_req);
1450                 return ret;
1451         }
1452
1453         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1454         if (ret) {
1455                 /*
1456                  * For callback during failure handling, push this work off
1457                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1458                  */
1459                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1460                 schedule_work(&se_cmd->work);
1461                 return 0;
1462         }
1463         transport_generic_handle_tmr(se_cmd);
1464         return 0;
1465 }
1466 EXPORT_SYMBOL(target_submit_tmr);
1467
1468 /*
1469  * If the cmd is active, request it to be stopped and sleep until it
1470  * has completed.
1471  */
1472 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1473 {
1474         bool was_active = false;
1475
1476         if (cmd->transport_state & CMD_T_BUSY) {
1477                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1478                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1479
1480                 pr_debug("cmd %p waiting to complete\n", cmd);
1481                 wait_for_completion(&cmd->task_stop_comp);
1482                 pr_debug("cmd %p stopped successfully\n", cmd);
1483
1484                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1485                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1486                 cmd->transport_state &= ~CMD_T_BUSY;
1487                 was_active = true;
1488         }
1489
1490         return was_active;
1491 }
1492
1493 /*
1494  * Handle SAM-esque emulation for generic transport request failures.
1495  */
1496 void transport_generic_request_failure(struct se_cmd *cmd,
1497                 sense_reason_t sense_reason)
1498 {
1499         int ret = 0;
1500
1501         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1502                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1503                 cmd->t_task_cdb[0]);
1504         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1505                 cmd->se_tfo->get_cmd_state(cmd),
1506                 cmd->t_state, sense_reason);
1507         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1508                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1509                 (cmd->transport_state & CMD_T_STOP) != 0,
1510                 (cmd->transport_state & CMD_T_SENT) != 0);
1511
1512         /*
1513          * For SAM Task Attribute emulation for failed struct se_cmd
1514          */
1515         transport_complete_task_attr(cmd);
1516
1517         switch (sense_reason) {
1518         case TCM_NON_EXISTENT_LUN:
1519         case TCM_UNSUPPORTED_SCSI_OPCODE:
1520         case TCM_INVALID_CDB_FIELD:
1521         case TCM_INVALID_PARAMETER_LIST:
1522         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1523         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1524         case TCM_UNKNOWN_MODE_PAGE:
1525         case TCM_WRITE_PROTECTED:
1526         case TCM_ADDRESS_OUT_OF_RANGE:
1527         case TCM_CHECK_CONDITION_ABORT_CMD:
1528         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1529         case TCM_CHECK_CONDITION_NOT_READY:
1530                 break;
1531         case TCM_OUT_OF_RESOURCES:
1532                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1533                 break;
1534         case TCM_RESERVATION_CONFLICT:
1535                 /*
1536                  * No SENSE Data payload for this case, set SCSI Status
1537                  * and queue the response to $FABRIC_MOD.
1538                  *
1539                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1540                  */
1541                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1542                 /*
1543                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1544                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1545                  * CONFLICT STATUS.
1546                  *
1547                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1548                  */
1549                 if (cmd->se_sess &&
1550                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1551                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1552                                 cmd->orig_fe_lun, 0x2C,
1553                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1554
1555                 ret = cmd->se_tfo->queue_status(cmd);
1556                 if (ret == -EAGAIN || ret == -ENOMEM)
1557                         goto queue_full;
1558                 goto check_stop;
1559         default:
1560                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1561                         cmd->t_task_cdb[0], sense_reason);
1562                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1563                 break;
1564         }
1565
1566         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1567         if (ret == -EAGAIN || ret == -ENOMEM)
1568                 goto queue_full;
1569
1570 check_stop:
1571         transport_lun_remove_cmd(cmd);
1572         if (!transport_cmd_check_stop_to_fabric(cmd))
1573                 ;
1574         return;
1575
1576 queue_full:
1577         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1578         transport_handle_queue_full(cmd, cmd->se_dev);
1579 }
1580 EXPORT_SYMBOL(transport_generic_request_failure);
1581
1582 static void __target_execute_cmd(struct se_cmd *cmd)
1583 {
1584         sense_reason_t ret;
1585
1586         spin_lock_irq(&cmd->t_state_lock);
1587         cmd->transport_state |= (CMD_T_BUSY|CMD_T_SENT);
1588         spin_unlock_irq(&cmd->t_state_lock);
1589
1590         if (cmd->execute_cmd) {
1591                 ret = cmd->execute_cmd(cmd);
1592                 if (ret) {
1593                         spin_lock_irq(&cmd->t_state_lock);
1594                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1595                         spin_unlock_irq(&cmd->t_state_lock);
1596
1597                         transport_generic_request_failure(cmd, ret);
1598                 }
1599         }
1600 }
1601
1602 static bool target_handle_task_attr(struct se_cmd *cmd)
1603 {
1604         struct se_device *dev = cmd->se_dev;
1605
1606         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1607                 return false;
1608
1609         /*
1610          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1611          * to allow the passed struct se_cmd list of tasks to the front of the list.
1612          */
1613         switch (cmd->sam_task_attr) {
1614         case MSG_HEAD_TAG:
1615                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1616                          "se_ordered_id: %u\n",
1617                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1618                 return false;
1619         case MSG_ORDERED_TAG:
1620                 atomic_inc(&dev->dev_ordered_sync);
1621                 smp_mb__after_atomic_inc();
1622
1623                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1624                          " se_ordered_id: %u\n",
1625                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1626
1627                 /*
1628                  * Execute an ORDERED command if no other older commands
1629                  * exist that need to be completed first.
1630                  */
1631                 if (!atomic_read(&dev->simple_cmds))
1632                         return false;
1633                 break;
1634         default:
1635                 /*
1636                  * For SIMPLE and UNTAGGED Task Attribute commands
1637                  */
1638                 atomic_inc(&dev->simple_cmds);
1639                 smp_mb__after_atomic_inc();
1640                 break;
1641         }
1642
1643         if (atomic_read(&dev->dev_ordered_sync) == 0)
1644                 return false;
1645
1646         spin_lock(&dev->delayed_cmd_lock);
1647         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1648         spin_unlock(&dev->delayed_cmd_lock);
1649
1650         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1651                 " delayed CMD list, se_ordered_id: %u\n",
1652                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1653                 cmd->se_ordered_id);
1654         return true;
1655 }
1656
1657 void target_execute_cmd(struct se_cmd *cmd)
1658 {
1659         /*
1660          * If the received CDB has aleady been aborted stop processing it here.
1661          */
1662         if (transport_check_aborted_status(cmd, 1)) {
1663                 complete(&cmd->transport_lun_stop_comp);
1664                 return;
1665         }
1666
1667         /*
1668          * Determine if IOCTL context caller in requesting the stopping of this
1669          * command for LUN shutdown purposes.
1670          */
1671         spin_lock_irq(&cmd->t_state_lock);
1672         if (cmd->transport_state & CMD_T_LUN_STOP) {
1673                 pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
1674                         __func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
1675
1676                 cmd->transport_state &= ~CMD_T_ACTIVE;
1677                 spin_unlock_irq(&cmd->t_state_lock);
1678                 complete(&cmd->transport_lun_stop_comp);
1679                 return;
1680         }
1681         /*
1682          * Determine if frontend context caller is requesting the stopping of
1683          * this command for frontend exceptions.
1684          */
1685         if (cmd->transport_state & CMD_T_STOP) {
1686                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1687                         __func__, __LINE__,
1688                         cmd->se_tfo->get_task_tag(cmd));
1689
1690                 spin_unlock_irq(&cmd->t_state_lock);
1691                 complete(&cmd->t_transport_stop_comp);
1692                 return;
1693         }
1694
1695         cmd->t_state = TRANSPORT_PROCESSING;
1696         cmd->transport_state |= CMD_T_ACTIVE;
1697         spin_unlock_irq(&cmd->t_state_lock);
1698
1699         if (!target_handle_task_attr(cmd))
1700                 __target_execute_cmd(cmd);
1701 }
1702 EXPORT_SYMBOL(target_execute_cmd);
1703
1704 /*
1705  * Process all commands up to the last received ORDERED task attribute which
1706  * requires another blocking boundary
1707  */
1708 static void target_restart_delayed_cmds(struct se_device *dev)
1709 {
1710         for (;;) {
1711                 struct se_cmd *cmd;
1712
1713                 spin_lock(&dev->delayed_cmd_lock);
1714                 if (list_empty(&dev->delayed_cmd_list)) {
1715                         spin_unlock(&dev->delayed_cmd_lock);
1716                         break;
1717                 }
1718
1719                 cmd = list_entry(dev->delayed_cmd_list.next,
1720                                  struct se_cmd, se_delayed_node);
1721                 list_del(&cmd->se_delayed_node);
1722                 spin_unlock(&dev->delayed_cmd_lock);
1723
1724                 __target_execute_cmd(cmd);
1725
1726                 if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1727                         break;
1728         }
1729 }
1730
1731 /*
1732  * Called from I/O completion to determine which dormant/delayed
1733  * and ordered cmds need to have their tasks added to the execution queue.
1734  */
1735 static void transport_complete_task_attr(struct se_cmd *cmd)
1736 {
1737         struct se_device *dev = cmd->se_dev;
1738
1739         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1740                 return;
1741
1742         if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1743                 atomic_dec(&dev->simple_cmds);
1744                 smp_mb__after_atomic_dec();
1745                 dev->dev_cur_ordered_id++;
1746                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1747                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1748                         cmd->se_ordered_id);
1749         } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1750                 dev->dev_cur_ordered_id++;
1751                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1752                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1753                         cmd->se_ordered_id);
1754         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1755                 atomic_dec(&dev->dev_ordered_sync);
1756                 smp_mb__after_atomic_dec();
1757
1758                 dev->dev_cur_ordered_id++;
1759                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1760                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1761         }
1762
1763         target_restart_delayed_cmds(dev);
1764 }
1765
1766 static void transport_complete_qf(struct se_cmd *cmd)
1767 {
1768         int ret = 0;
1769
1770         transport_complete_task_attr(cmd);
1771
1772         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1773                 ret = cmd->se_tfo->queue_status(cmd);
1774                 if (ret)
1775                         goto out;
1776         }
1777
1778         switch (cmd->data_direction) {
1779         case DMA_FROM_DEVICE:
1780                 ret = cmd->se_tfo->queue_data_in(cmd);
1781                 break;
1782         case DMA_TO_DEVICE:
1783                 if (cmd->t_bidi_data_sg) {
1784                         ret = cmd->se_tfo->queue_data_in(cmd);
1785                         if (ret < 0)
1786                                 break;
1787                 }
1788                 /* Fall through for DMA_TO_DEVICE */
1789         case DMA_NONE:
1790                 ret = cmd->se_tfo->queue_status(cmd);
1791                 break;
1792         default:
1793                 break;
1794         }
1795
1796 out:
1797         if (ret < 0) {
1798                 transport_handle_queue_full(cmd, cmd->se_dev);
1799                 return;
1800         }
1801         transport_lun_remove_cmd(cmd);
1802         transport_cmd_check_stop_to_fabric(cmd);
1803 }
1804
1805 static void transport_handle_queue_full(
1806         struct se_cmd *cmd,
1807         struct se_device *dev)
1808 {
1809         spin_lock_irq(&dev->qf_cmd_lock);
1810         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1811         atomic_inc(&dev->dev_qf_count);
1812         smp_mb__after_atomic_inc();
1813         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1814
1815         schedule_work(&cmd->se_dev->qf_work_queue);
1816 }
1817
1818 static void target_complete_ok_work(struct work_struct *work)
1819 {
1820         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1821         int ret;
1822
1823         /*
1824          * Check if we need to move delayed/dormant tasks from cmds on the
1825          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1826          * Attribute.
1827          */
1828         transport_complete_task_attr(cmd);
1829
1830         /*
1831          * Check to schedule QUEUE_FULL work, or execute an existing
1832          * cmd->transport_qf_callback()
1833          */
1834         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1835                 schedule_work(&cmd->se_dev->qf_work_queue);
1836
1837         /*
1838          * Check if we need to send a sense buffer from
1839          * the struct se_cmd in question.
1840          */
1841         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1842                 WARN_ON(!cmd->scsi_status);
1843                 ret = transport_send_check_condition_and_sense(
1844                                         cmd, 0, 1);
1845                 if (ret == -EAGAIN || ret == -ENOMEM)
1846                         goto queue_full;
1847
1848                 transport_lun_remove_cmd(cmd);
1849                 transport_cmd_check_stop_to_fabric(cmd);
1850                 return;
1851         }
1852         /*
1853          * Check for a callback, used by amongst other things
1854          * XDWRITE_READ_10 emulation.
1855          */
1856         if (cmd->transport_complete_callback)
1857                 cmd->transport_complete_callback(cmd);
1858
1859         switch (cmd->data_direction) {
1860         case DMA_FROM_DEVICE:
1861                 spin_lock(&cmd->se_lun->lun_sep_lock);
1862                 if (cmd->se_lun->lun_sep) {
1863                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1864                                         cmd->data_length;
1865                 }
1866                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1867
1868                 ret = cmd->se_tfo->queue_data_in(cmd);
1869                 if (ret == -EAGAIN || ret == -ENOMEM)
1870                         goto queue_full;
1871                 break;
1872         case DMA_TO_DEVICE:
1873                 spin_lock(&cmd->se_lun->lun_sep_lock);
1874                 if (cmd->se_lun->lun_sep) {
1875                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
1876                                 cmd->data_length;
1877                 }
1878                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1879                 /*
1880                  * Check if we need to send READ payload for BIDI-COMMAND
1881                  */
1882                 if (cmd->t_bidi_data_sg) {
1883                         spin_lock(&cmd->se_lun->lun_sep_lock);
1884                         if (cmd->se_lun->lun_sep) {
1885                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1886                                         cmd->data_length;
1887                         }
1888                         spin_unlock(&cmd->se_lun->lun_sep_lock);
1889                         ret = cmd->se_tfo->queue_data_in(cmd);
1890                         if (ret == -EAGAIN || ret == -ENOMEM)
1891                                 goto queue_full;
1892                         break;
1893                 }
1894                 /* Fall through for DMA_TO_DEVICE */
1895         case DMA_NONE:
1896                 ret = cmd->se_tfo->queue_status(cmd);
1897                 if (ret == -EAGAIN || ret == -ENOMEM)
1898                         goto queue_full;
1899                 break;
1900         default:
1901                 break;
1902         }
1903
1904         transport_lun_remove_cmd(cmd);
1905         transport_cmd_check_stop_to_fabric(cmd);
1906         return;
1907
1908 queue_full:
1909         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
1910                 " data_direction: %d\n", cmd, cmd->data_direction);
1911         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1912         transport_handle_queue_full(cmd, cmd->se_dev);
1913 }
1914
1915 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
1916 {
1917         struct scatterlist *sg;
1918         int count;
1919
1920         for_each_sg(sgl, sg, nents, count)
1921                 __free_page(sg_page(sg));
1922
1923         kfree(sgl);
1924 }
1925
1926 static inline void transport_free_pages(struct se_cmd *cmd)
1927 {
1928         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
1929                 return;
1930
1931         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
1932         cmd->t_data_sg = NULL;
1933         cmd->t_data_nents = 0;
1934
1935         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
1936         cmd->t_bidi_data_sg = NULL;
1937         cmd->t_bidi_data_nents = 0;
1938 }
1939
1940 /**
1941  * transport_release_cmd - free a command
1942  * @cmd:       command to free
1943  *
1944  * This routine unconditionally frees a command, and reference counting
1945  * or list removal must be done in the caller.
1946  */
1947 static void transport_release_cmd(struct se_cmd *cmd)
1948 {
1949         BUG_ON(!cmd->se_tfo);
1950
1951         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
1952                 core_tmr_release_req(cmd->se_tmr_req);
1953         if (cmd->t_task_cdb != cmd->__t_task_cdb)
1954                 kfree(cmd->t_task_cdb);
1955         /*
1956          * If this cmd has been setup with target_get_sess_cmd(), drop
1957          * the kref and call ->release_cmd() in kref callback.
1958          */
1959          if (cmd->check_release != 0) {
1960                 target_put_sess_cmd(cmd->se_sess, cmd);
1961                 return;
1962         }
1963         cmd->se_tfo->release_cmd(cmd);
1964 }
1965
1966 /**
1967  * transport_put_cmd - release a reference to a command
1968  * @cmd:       command to release
1969  *
1970  * This routine releases our reference to the command and frees it if possible.
1971  */
1972 static void transport_put_cmd(struct se_cmd *cmd)
1973 {
1974         unsigned long flags;
1975
1976         spin_lock_irqsave(&cmd->t_state_lock, flags);
1977         if (atomic_read(&cmd->t_fe_count) &&
1978             !atomic_dec_and_test(&cmd->t_fe_count)) {
1979                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1980                 return;
1981         }
1982
1983         if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
1984                 cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
1985                 target_remove_from_state_list(cmd);
1986         }
1987         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
1988
1989         transport_free_pages(cmd);
1990         transport_release_cmd(cmd);
1991         return;
1992 }
1993
1994 void *transport_kmap_data_sg(struct se_cmd *cmd)
1995 {
1996         struct scatterlist *sg = cmd->t_data_sg;
1997         struct page **pages;
1998         int i;
1999
2000         /*
2001          * We need to take into account a possible offset here for fabrics like
2002          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2003          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2004          */
2005         if (!cmd->t_data_nents)
2006                 return NULL;
2007
2008         BUG_ON(!sg);
2009         if (cmd->t_data_nents == 1)
2010                 return kmap(sg_page(sg)) + sg->offset;
2011
2012         /* >1 page. use vmap */
2013         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2014         if (!pages)
2015                 return NULL;
2016
2017         /* convert sg[] to pages[] */
2018         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2019                 pages[i] = sg_page(sg);
2020         }
2021
2022         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2023         kfree(pages);
2024         if (!cmd->t_data_vmap)
2025                 return NULL;
2026
2027         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2028 }
2029 EXPORT_SYMBOL(transport_kmap_data_sg);
2030
2031 void transport_kunmap_data_sg(struct se_cmd *cmd)
2032 {
2033         if (!cmd->t_data_nents) {
2034                 return;
2035         } else if (cmd->t_data_nents == 1) {
2036                 kunmap(sg_page(cmd->t_data_sg));
2037                 return;
2038         }
2039
2040         vunmap(cmd->t_data_vmap);
2041         cmd->t_data_vmap = NULL;
2042 }
2043 EXPORT_SYMBOL(transport_kunmap_data_sg);
2044
2045 static int
2046 transport_generic_get_mem(struct se_cmd *cmd)
2047 {
2048         u32 length = cmd->data_length;
2049         unsigned int nents;
2050         struct page *page;
2051         gfp_t zero_flag;
2052         int i = 0;
2053
2054         nents = DIV_ROUND_UP(length, PAGE_SIZE);
2055         cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
2056         if (!cmd->t_data_sg)
2057                 return -ENOMEM;
2058
2059         cmd->t_data_nents = nents;
2060         sg_init_table(cmd->t_data_sg, nents);
2061
2062         zero_flag = cmd->se_cmd_flags & SCF_SCSI_DATA_CDB ? 0 : __GFP_ZERO;
2063
2064         while (length) {
2065                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2066                 page = alloc_page(GFP_KERNEL | zero_flag);
2067                 if (!page)
2068                         goto out;
2069
2070                 sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
2071                 length -= page_len;
2072                 i++;
2073         }
2074         return 0;
2075
2076 out:
2077         while (i > 0) {
2078                 i--;
2079                 __free_page(sg_page(&cmd->t_data_sg[i]));
2080         }
2081         kfree(cmd->t_data_sg);
2082         cmd->t_data_sg = NULL;
2083         return -ENOMEM;
2084 }
2085
2086 /*
2087  * Allocate any required resources to execute the command.  For writes we
2088  * might not have the payload yet, so notify the fabric via a call to
2089  * ->write_pending instead. Otherwise place it on the execution queue.
2090  */
2091 sense_reason_t
2092 transport_generic_new_cmd(struct se_cmd *cmd)
2093 {
2094         int ret = 0;
2095
2096         /*
2097          * Determine is the TCM fabric module has already allocated physical
2098          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2099          * beforehand.
2100          */
2101         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2102             cmd->data_length) {
2103                 ret = transport_generic_get_mem(cmd);
2104                 if (ret < 0)
2105                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2106         }
2107
2108         atomic_inc(&cmd->t_fe_count);
2109
2110         /*
2111          * If this command is not a write we can execute it right here,
2112          * for write buffers we need to notify the fabric driver first
2113          * and let it call back once the write buffers are ready.
2114          */
2115         target_add_to_state_list(cmd);
2116         if (cmd->data_direction != DMA_TO_DEVICE) {
2117                 target_execute_cmd(cmd);
2118                 return 0;
2119         }
2120
2121         spin_lock_irq(&cmd->t_state_lock);
2122         cmd->t_state = TRANSPORT_WRITE_PENDING;
2123         spin_unlock_irq(&cmd->t_state_lock);
2124
2125         transport_cmd_check_stop(cmd, false);
2126
2127         ret = cmd->se_tfo->write_pending(cmd);
2128         if (ret == -EAGAIN || ret == -ENOMEM)
2129                 goto queue_full;
2130
2131         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2132         WARN_ON(ret);
2133
2134         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2135
2136 queue_full:
2137         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2138         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2139         transport_handle_queue_full(cmd, cmd->se_dev);
2140         return 0;
2141 }
2142 EXPORT_SYMBOL(transport_generic_new_cmd);
2143
2144 static void transport_write_pending_qf(struct se_cmd *cmd)
2145 {
2146         int ret;
2147
2148         ret = cmd->se_tfo->write_pending(cmd);
2149         if (ret == -EAGAIN || ret == -ENOMEM) {
2150                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2151                          cmd);
2152                 transport_handle_queue_full(cmd, cmd->se_dev);
2153         }
2154 }
2155
2156 void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2157 {
2158         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2159                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2160                          transport_wait_for_tasks(cmd);
2161
2162                 transport_release_cmd(cmd);
2163         } else {
2164                 if (wait_for_tasks)
2165                         transport_wait_for_tasks(cmd);
2166
2167                 core_dec_lacl_count(cmd->se_sess->se_node_acl, cmd);
2168
2169                 if (cmd->se_lun)
2170                         transport_lun_remove_cmd(cmd);
2171
2172                 transport_put_cmd(cmd);
2173         }
2174 }
2175 EXPORT_SYMBOL(transport_generic_free_cmd);
2176
2177 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2178  * @se_sess:    session to reference
2179  * @se_cmd:     command descriptor to add
2180  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2181  */
2182 static int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2183                                bool ack_kref)
2184 {
2185         unsigned long flags;
2186         int ret = 0;
2187
2188         kref_init(&se_cmd->cmd_kref);
2189         /*
2190          * Add a second kref if the fabric caller is expecting to handle
2191          * fabric acknowledgement that requires two target_put_sess_cmd()
2192          * invocations before se_cmd descriptor release.
2193          */
2194         if (ack_kref == true) {
2195                 kref_get(&se_cmd->cmd_kref);
2196                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2197         }
2198
2199         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2200         if (se_sess->sess_tearing_down) {
2201                 ret = -ESHUTDOWN;
2202                 goto out;
2203         }
2204         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2205         se_cmd->check_release = 1;
2206
2207 out:
2208         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2209         return ret;
2210 }
2211
2212 static void target_release_cmd_kref(struct kref *kref)
2213 {
2214         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2215         struct se_session *se_sess = se_cmd->se_sess;
2216         unsigned long flags;
2217
2218         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2219         if (list_empty(&se_cmd->se_cmd_list)) {
2220                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2221                 se_cmd->se_tfo->release_cmd(se_cmd);
2222                 return;
2223         }
2224         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2225                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2226                 complete(&se_cmd->cmd_wait_comp);
2227                 return;
2228         }
2229         list_del(&se_cmd->se_cmd_list);
2230         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2231
2232         se_cmd->se_tfo->release_cmd(se_cmd);
2233 }
2234
2235 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2236  * @se_sess:    session to reference
2237  * @se_cmd:     command descriptor to drop
2238  */
2239 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2240 {
2241         return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2242 }
2243 EXPORT_SYMBOL(target_put_sess_cmd);
2244
2245 /* target_sess_cmd_list_set_waiting - Flag all commands in
2246  *         sess_cmd_list to complete cmd_wait_comp.  Set
2247  *         sess_tearing_down so no more commands are queued.
2248  * @se_sess:    session to flag
2249  */
2250 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2251 {
2252         struct se_cmd *se_cmd;
2253         unsigned long flags;
2254
2255         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2256
2257         WARN_ON(se_sess->sess_tearing_down);
2258         se_sess->sess_tearing_down = 1;
2259
2260         list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list)
2261                 se_cmd->cmd_wait_set = 1;
2262
2263         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2264 }
2265 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2266
2267 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2268  * @se_sess:    session to wait for active I/O
2269  * @wait_for_tasks:     Make extra transport_wait_for_tasks call
2270  */
2271 void target_wait_for_sess_cmds(
2272         struct se_session *se_sess,
2273         int wait_for_tasks)
2274 {
2275         struct se_cmd *se_cmd, *tmp_cmd;
2276         bool rc = false;
2277
2278         list_for_each_entry_safe(se_cmd, tmp_cmd,
2279                                 &se_sess->sess_cmd_list, se_cmd_list) {
2280                 list_del(&se_cmd->se_cmd_list);
2281
2282                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2283                         " %d\n", se_cmd, se_cmd->t_state,
2284                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2285
2286                 if (wait_for_tasks) {
2287                         pr_debug("Calling transport_wait_for_tasks se_cmd: %p t_state: %d,"
2288                                 " fabric state: %d\n", se_cmd, se_cmd->t_state,
2289                                 se_cmd->se_tfo->get_cmd_state(se_cmd));
2290
2291                         rc = transport_wait_for_tasks(se_cmd);
2292
2293                         pr_debug("After transport_wait_for_tasks se_cmd: %p t_state: %d,"
2294                                 " fabric state: %d\n", se_cmd, se_cmd->t_state,
2295                                 se_cmd->se_tfo->get_cmd_state(se_cmd));
2296                 }
2297
2298                 if (!rc) {
2299                         wait_for_completion(&se_cmd->cmd_wait_comp);
2300                         pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2301                                 " fabric state: %d\n", se_cmd, se_cmd->t_state,
2302                                 se_cmd->se_tfo->get_cmd_state(se_cmd));
2303                 }
2304
2305                 se_cmd->se_tfo->release_cmd(se_cmd);
2306         }
2307 }
2308 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2309
2310 /*      transport_lun_wait_for_tasks():
2311  *
2312  *      Called from ConfigFS context to stop the passed struct se_cmd to allow
2313  *      an struct se_lun to be successfully shutdown.
2314  */
2315 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
2316 {
2317         unsigned long flags;
2318         int ret = 0;
2319
2320         /*
2321          * If the frontend has already requested this struct se_cmd to
2322          * be stopped, we can safely ignore this struct se_cmd.
2323          */
2324         spin_lock_irqsave(&cmd->t_state_lock, flags);
2325         if (cmd->transport_state & CMD_T_STOP) {
2326                 cmd->transport_state &= ~CMD_T_LUN_STOP;
2327
2328                 pr_debug("ConfigFS ITT[0x%08x] - CMD_T_STOP, skipping\n",
2329                          cmd->se_tfo->get_task_tag(cmd));
2330                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2331                 transport_cmd_check_stop(cmd, false);
2332                 return -EPERM;
2333         }
2334         cmd->transport_state |= CMD_T_LUN_FE_STOP;
2335         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2336
2337         // XXX: audit task_flags checks.
2338         spin_lock_irqsave(&cmd->t_state_lock, flags);
2339         if ((cmd->transport_state & CMD_T_BUSY) &&
2340             (cmd->transport_state & CMD_T_SENT)) {
2341                 if (!target_stop_cmd(cmd, &flags))
2342                         ret++;
2343         }
2344         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2345
2346         pr_debug("ConfigFS: cmd: %p stop tasks ret:"
2347                         " %d\n", cmd, ret);
2348         if (!ret) {
2349                 pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
2350                                 cmd->se_tfo->get_task_tag(cmd));
2351                 wait_for_completion(&cmd->transport_lun_stop_comp);
2352                 pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
2353                                 cmd->se_tfo->get_task_tag(cmd));
2354         }
2355
2356         return 0;
2357 }
2358
2359 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
2360 {
2361         struct se_cmd *cmd = NULL;
2362         unsigned long lun_flags, cmd_flags;
2363         /*
2364          * Do exception processing and return CHECK_CONDITION status to the
2365          * Initiator Port.
2366          */
2367         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2368         while (!list_empty(&lun->lun_cmd_list)) {
2369                 cmd = list_first_entry(&lun->lun_cmd_list,
2370                        struct se_cmd, se_lun_node);
2371                 list_del_init(&cmd->se_lun_node);
2372
2373                 spin_lock(&cmd->t_state_lock);
2374                 pr_debug("SE_LUN[%d] - Setting cmd->transport"
2375                         "_lun_stop for  ITT: 0x%08x\n",
2376                         cmd->se_lun->unpacked_lun,
2377                         cmd->se_tfo->get_task_tag(cmd));
2378                 cmd->transport_state |= CMD_T_LUN_STOP;
2379                 spin_unlock(&cmd->t_state_lock);
2380
2381                 spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2382
2383                 if (!cmd->se_lun) {
2384                         pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
2385                                 cmd->se_tfo->get_task_tag(cmd),
2386                                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2387                         BUG();
2388                 }
2389                 /*
2390                  * If the Storage engine still owns the iscsi_cmd_t, determine
2391                  * and/or stop its context.
2392                  */
2393                 pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
2394                         "_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
2395                         cmd->se_tfo->get_task_tag(cmd));
2396
2397                 if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
2398                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2399                         continue;
2400                 }
2401
2402                 pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
2403                         "_wait_for_tasks(): SUCCESS\n",
2404                         cmd->se_lun->unpacked_lun,
2405                         cmd->se_tfo->get_task_tag(cmd));
2406
2407                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2408                 if (!(cmd->transport_state & CMD_T_DEV_ACTIVE)) {
2409                         spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2410                         goto check_cond;
2411                 }
2412                 cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
2413                 target_remove_from_state_list(cmd);
2414                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2415
2416                 /*
2417                  * The Storage engine stopped this struct se_cmd before it was
2418                  * send to the fabric frontend for delivery back to the
2419                  * Initiator Node.  Return this SCSI CDB back with an
2420                  * CHECK_CONDITION status.
2421                  */
2422 check_cond:
2423                 transport_send_check_condition_and_sense(cmd,
2424                                 TCM_NON_EXISTENT_LUN, 0);
2425                 /*
2426                  *  If the fabric frontend is waiting for this iscsi_cmd_t to
2427                  * be released, notify the waiting thread now that LU has
2428                  * finished accessing it.
2429                  */
2430                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2431                 if (cmd->transport_state & CMD_T_LUN_FE_STOP) {
2432                         pr_debug("SE_LUN[%d] - Detected FE stop for"
2433                                 " struct se_cmd: %p ITT: 0x%08x\n",
2434                                 lun->unpacked_lun,
2435                                 cmd, cmd->se_tfo->get_task_tag(cmd));
2436
2437                         spin_unlock_irqrestore(&cmd->t_state_lock,
2438                                         cmd_flags);
2439                         transport_cmd_check_stop(cmd, false);
2440                         complete(&cmd->transport_lun_fe_stop_comp);
2441                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2442                         continue;
2443                 }
2444                 pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
2445                         lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
2446
2447                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2448                 spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2449         }
2450         spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2451 }
2452
2453 static int transport_clear_lun_thread(void *p)
2454 {
2455         struct se_lun *lun = p;
2456
2457         __transport_clear_lun_from_sessions(lun);
2458         complete(&lun->lun_shutdown_comp);
2459
2460         return 0;
2461 }
2462
2463 int transport_clear_lun_from_sessions(struct se_lun *lun)
2464 {
2465         struct task_struct *kt;
2466
2467         kt = kthread_run(transport_clear_lun_thread, lun,
2468                         "tcm_cl_%u", lun->unpacked_lun);
2469         if (IS_ERR(kt)) {
2470                 pr_err("Unable to start clear_lun thread\n");
2471                 return PTR_ERR(kt);
2472         }
2473         wait_for_completion(&lun->lun_shutdown_comp);
2474
2475         return 0;
2476 }
2477
2478 /**
2479  * transport_wait_for_tasks - wait for completion to occur
2480  * @cmd:        command to wait
2481  *
2482  * Called from frontend fabric context to wait for storage engine
2483  * to pause and/or release frontend generated struct se_cmd.
2484  */
2485 bool transport_wait_for_tasks(struct se_cmd *cmd)
2486 {
2487         unsigned long flags;
2488
2489         spin_lock_irqsave(&cmd->t_state_lock, flags);
2490         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2491             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2492                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2493                 return false;
2494         }
2495
2496         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2497             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2498                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2499                 return false;
2500         }
2501         /*
2502          * If we are already stopped due to an external event (ie: LUN shutdown)
2503          * sleep until the connection can have the passed struct se_cmd back.
2504          * The cmd->transport_lun_stopped_sem will be upped by
2505          * transport_clear_lun_from_sessions() once the ConfigFS context caller
2506          * has completed its operation on the struct se_cmd.
2507          */
2508         if (cmd->transport_state & CMD_T_LUN_STOP) {
2509                 pr_debug("wait_for_tasks: Stopping"
2510                         " wait_for_completion(&cmd->t_tasktransport_lun_fe"
2511                         "_stop_comp); for ITT: 0x%08x\n",
2512                         cmd->se_tfo->get_task_tag(cmd));
2513                 /*
2514                  * There is a special case for WRITES where a FE exception +
2515                  * LUN shutdown means ConfigFS context is still sleeping on
2516                  * transport_lun_stop_comp in transport_lun_wait_for_tasks().
2517                  * We go ahead and up transport_lun_stop_comp just to be sure
2518                  * here.
2519                  */
2520                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2521                 complete(&cmd->transport_lun_stop_comp);
2522                 wait_for_completion(&cmd->transport_lun_fe_stop_comp);
2523                 spin_lock_irqsave(&cmd->t_state_lock, flags);
2524
2525                 target_remove_from_state_list(cmd);
2526                 /*
2527                  * At this point, the frontend who was the originator of this
2528                  * struct se_cmd, now owns the structure and can be released through
2529                  * normal means below.
2530                  */
2531                 pr_debug("wait_for_tasks: Stopped"
2532                         " wait_for_completion(&cmd->t_tasktransport_lun_fe_"
2533                         "stop_comp); for ITT: 0x%08x\n",
2534                         cmd->se_tfo->get_task_tag(cmd));
2535
2536                 cmd->transport_state &= ~CMD_T_LUN_STOP;
2537         }
2538
2539         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2540                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2541                 return false;
2542         }
2543
2544         cmd->transport_state |= CMD_T_STOP;
2545
2546         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2547                 " i_state: %d, t_state: %d, CMD_T_STOP\n",
2548                 cmd, cmd->se_tfo->get_task_tag(cmd),
2549                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2550
2551         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2552
2553         wait_for_completion(&cmd->t_transport_stop_comp);
2554
2555         spin_lock_irqsave(&cmd->t_state_lock, flags);
2556         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2557
2558         pr_debug("wait_for_tasks: Stopped wait_for_completion("
2559                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2560                 cmd->se_tfo->get_task_tag(cmd));
2561
2562         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2563
2564         return true;
2565 }
2566 EXPORT_SYMBOL(transport_wait_for_tasks);
2567
2568 static int transport_get_sense_codes(
2569         struct se_cmd *cmd,
2570         u8 *asc,
2571         u8 *ascq)
2572 {
2573         *asc = cmd->scsi_asc;
2574         *ascq = cmd->scsi_ascq;
2575
2576         return 0;
2577 }
2578
2579 int
2580 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2581                 sense_reason_t reason, int from_transport)
2582 {
2583         unsigned char *buffer = cmd->sense_buffer;
2584         unsigned long flags;
2585         u8 asc = 0, ascq = 0;
2586
2587         spin_lock_irqsave(&cmd->t_state_lock, flags);
2588         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2589                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2590                 return 0;
2591         }
2592         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2593         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2594
2595         if (!reason && from_transport)
2596                 goto after_reason;
2597
2598         if (!from_transport)
2599                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2600
2601         /*
2602          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2603          * SENSE KEY values from include/scsi/scsi.h
2604          */
2605         switch (reason) {
2606         case TCM_NO_SENSE:
2607                 /* CURRENT ERROR */
2608                 buffer[0] = 0x70;
2609                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2610                 /* Not Ready */
2611                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2612                 /* NO ADDITIONAL SENSE INFORMATION */
2613                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2614                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2615                 break;
2616         case TCM_NON_EXISTENT_LUN:
2617                 /* CURRENT ERROR */
2618                 buffer[0] = 0x70;
2619                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2620                 /* ILLEGAL REQUEST */
2621                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2622                 /* LOGICAL UNIT NOT SUPPORTED */
2623                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2624                 break;
2625         case TCM_UNSUPPORTED_SCSI_OPCODE:
2626         case TCM_SECTOR_COUNT_TOO_MANY:
2627                 /* CURRENT ERROR */
2628                 buffer[0] = 0x70;
2629                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2630                 /* ILLEGAL REQUEST */
2631                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2632                 /* INVALID COMMAND OPERATION CODE */
2633                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2634                 break;
2635         case TCM_UNKNOWN_MODE_PAGE:
2636                 /* CURRENT ERROR */
2637                 buffer[0] = 0x70;
2638                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2639                 /* ILLEGAL REQUEST */
2640                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2641                 /* INVALID FIELD IN CDB */
2642                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2643                 break;
2644         case TCM_CHECK_CONDITION_ABORT_CMD:
2645                 /* CURRENT ERROR */
2646                 buffer[0] = 0x70;
2647                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2648                 /* ABORTED COMMAND */
2649                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2650                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2651                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2652                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2653                 break;
2654         case TCM_INCORRECT_AMOUNT_OF_DATA:
2655                 /* CURRENT ERROR */
2656                 buffer[0] = 0x70;
2657                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2658                 /* ABORTED COMMAND */
2659                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2660                 /* WRITE ERROR */
2661                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2662                 /* NOT ENOUGH UNSOLICITED DATA */
2663                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2664                 break;
2665         case TCM_INVALID_CDB_FIELD:
2666                 /* CURRENT ERROR */
2667                 buffer[0] = 0x70;
2668                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2669                 /* ILLEGAL REQUEST */
2670                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2671                 /* INVALID FIELD IN CDB */
2672                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2673                 break;
2674         case TCM_INVALID_PARAMETER_LIST:
2675                 /* CURRENT ERROR */
2676                 buffer[0] = 0x70;
2677                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2678                 /* ILLEGAL REQUEST */
2679                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2680                 /* INVALID FIELD IN PARAMETER LIST */
2681                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2682                 break;
2683         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2684                 /* CURRENT ERROR */
2685                 buffer[0] = 0x70;
2686                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2687                 /* ILLEGAL REQUEST */
2688                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2689                 /* PARAMETER LIST LENGTH ERROR */
2690                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2691                 break;
2692         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2693                 /* CURRENT ERROR */
2694                 buffer[0] = 0x70;
2695                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2696                 /* ABORTED COMMAND */
2697                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2698                 /* WRITE ERROR */
2699                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2700                 /* UNEXPECTED_UNSOLICITED_DATA */
2701                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2702                 break;
2703         case TCM_SERVICE_CRC_ERROR:
2704                 /* CURRENT ERROR */
2705                 buffer[0] = 0x70;
2706                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2707                 /* ABORTED COMMAND */
2708                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2709                 /* PROTOCOL SERVICE CRC ERROR */
2710                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2711                 /* N/A */
2712                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2713                 break;
2714         case TCM_SNACK_REJECTED:
2715                 /* CURRENT ERROR */
2716                 buffer[0] = 0x70;
2717                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2718                 /* ABORTED COMMAND */
2719                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2720                 /* READ ERROR */
2721                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2722                 /* FAILED RETRANSMISSION REQUEST */
2723                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2724                 break;
2725         case TCM_WRITE_PROTECTED:
2726                 /* CURRENT ERROR */
2727                 buffer[0] = 0x70;
2728                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2729                 /* DATA PROTECT */
2730                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2731                 /* WRITE PROTECTED */
2732                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2733                 break;
2734         case TCM_ADDRESS_OUT_OF_RANGE:
2735                 /* CURRENT ERROR */
2736                 buffer[0] = 0x70;
2737                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2738                 /* ILLEGAL REQUEST */
2739                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2740                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2741                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2742                 break;
2743         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2744                 /* CURRENT ERROR */
2745                 buffer[0] = 0x70;
2746                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2747                 /* UNIT ATTENTION */
2748                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2749                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2750                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2751                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2752                 break;
2753         case TCM_CHECK_CONDITION_NOT_READY:
2754                 /* CURRENT ERROR */
2755                 buffer[0] = 0x70;
2756                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2757                 /* Not Ready */
2758                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2759                 transport_get_sense_codes(cmd, &asc, &ascq);
2760                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2761                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2762                 break;
2763         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2764         default:
2765                 /* CURRENT ERROR */
2766                 buffer[0] = 0x70;
2767                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2768                 /* ILLEGAL REQUEST */
2769                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2770                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2771                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2772                 break;
2773         }
2774         /*
2775          * This code uses linux/include/scsi/scsi.h SAM status codes!
2776          */
2777         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2778         /*
2779          * Automatically padded, this value is encoded in the fabric's
2780          * data_length response PDU containing the SCSI defined sense data.
2781          */
2782         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2783
2784 after_reason:
2785         return cmd->se_tfo->queue_status(cmd);
2786 }
2787 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2788
2789 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2790 {
2791         if (!(cmd->transport_state & CMD_T_ABORTED))
2792                 return 0;
2793
2794         if (!send_status || (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
2795                 return 1;
2796
2797         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2798                  cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2799
2800         cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
2801         cmd->se_tfo->queue_status(cmd);
2802
2803         return 1;
2804 }
2805 EXPORT_SYMBOL(transport_check_aborted_status);
2806
2807 void transport_send_task_abort(struct se_cmd *cmd)
2808 {
2809         unsigned long flags;
2810
2811         spin_lock_irqsave(&cmd->t_state_lock, flags);
2812         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION | SCF_SENT_DELAYED_TAS)) {
2813                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2814                 return;
2815         }
2816         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2817
2818         /*
2819          * If there are still expected incoming fabric WRITEs, we wait
2820          * until until they have completed before sending a TASK_ABORTED
2821          * response.  This response with TASK_ABORTED status will be
2822          * queued back to fabric module by transport_check_aborted_status().
2823          */
2824         if (cmd->data_direction == DMA_TO_DEVICE) {
2825                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2826                         cmd->transport_state |= CMD_T_ABORTED;
2827                         smp_mb__after_atomic_inc();
2828                 }
2829         }
2830         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2831
2832         transport_lun_remove_cmd(cmd);
2833
2834         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2835                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
2836                 cmd->se_tfo->get_task_tag(cmd));
2837
2838         cmd->se_tfo->queue_status(cmd);
2839 }
2840
2841 static void target_tmr_work(struct work_struct *work)
2842 {
2843         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2844         struct se_device *dev = cmd->se_dev;
2845         struct se_tmr_req *tmr = cmd->se_tmr_req;
2846         int ret;
2847
2848         switch (tmr->function) {
2849         case TMR_ABORT_TASK:
2850                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2851                 break;
2852         case TMR_ABORT_TASK_SET:
2853         case TMR_CLEAR_ACA:
2854         case TMR_CLEAR_TASK_SET:
2855                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2856                 break;
2857         case TMR_LUN_RESET:
2858                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2859                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2860                                          TMR_FUNCTION_REJECTED;
2861                 break;
2862         case TMR_TARGET_WARM_RESET:
2863                 tmr->response = TMR_FUNCTION_REJECTED;
2864                 break;
2865         case TMR_TARGET_COLD_RESET:
2866                 tmr->response = TMR_FUNCTION_REJECTED;
2867                 break;
2868         default:
2869                 pr_err("Uknown TMR function: 0x%02x.\n",
2870                                 tmr->function);
2871                 tmr->response = TMR_FUNCTION_REJECTED;
2872                 break;
2873         }
2874
2875         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2876         cmd->se_tfo->queue_tm_rsp(cmd);
2877
2878         transport_cmd_check_stop_to_fabric(cmd);
2879 }
2880
2881 int transport_generic_handle_tmr(
2882         struct se_cmd *cmd)
2883 {
2884         INIT_WORK(&cmd->work, target_tmr_work);
2885         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2886         return 0;
2887 }
2888 EXPORT_SYMBOL(transport_generic_handle_tmr);