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