drivers/target/target_core_transport.c

   1 /*******************************************************************************
   2  * Filename:  target_core_transport.c
   3  *
   4  * This file contains the Generic Target Engine Core.
   5  *
   6  * (c) Copyright 2002-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/net.h>
  27 #include <linux/delay.h>
  28 #include <linux/string.h>
  29 #include <linux/timer.h>
  30 #include <linux/slab.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/kthread.h>
  33 #include <linux/in.h>
  34 #include <linux/cdrom.h>
  35 #include <linux/module.h>
  36 #include <linux/ratelimit.h>
  37 #include <asm/unaligned.h>
  38 #include <net/sock.h>
  39 #include <net/tcp.h>
  40 #include <scsi/scsi.h>
  41 #include <scsi/scsi_cmnd.h>
  42 #include <scsi/scsi_tcq.h>
  43
  44 #include <target/target_core_base.h>
  45 #include <target/target_core_backend.h>
  46 #include <target/target_core_fabric.h>
  47 #include <target/target_core_configfs.h>
  48
  49 #include "target_core_internal.h"
  50 #include "target_core_alua.h"
  51 #include "target_core_pr.h"
  52 #include "target_core_ua.h"
  53
  54 #define CREATE_TRACE_POINTS
  55 #include <trace/events/target.h>
  56
  57 static struct workqueue_struct *target_completion_wq;
  58 static struct kmem_cache *se_sess_cache;
  59 struct kmem_cache *se_ua_cache;
  60 struct kmem_cache *t10_pr_reg_cache;
  61 struct kmem_cache *t10_alua_lu_gp_cache;
  62 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  63 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  64 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
  65 struct kmem_cache *t10_alua_lba_map_cache;
  66 struct kmem_cache *t10_alua_lba_map_mem_cache;
  67
  68 static void transport_complete_task_attr(struct se_cmd *cmd);
  69 static void transport_handle_queue_full(struct se_cmd *cmd,
  70                 struct se_device *dev);
  71 static int transport_put_cmd(struct se_cmd *cmd);
  72 static void target_complete_ok_work(struct work_struct *work);
  73
  74 int init_se_kmem_caches(void)
  75 {
  76         se_sess_cache = kmem_cache_create("se_sess_cache",
  77                         sizeof(struct se_session), __alignof__(struct se_session),
  78                         0, NULL);
  79         if (!se_sess_cache) {
  80                 pr_err("kmem_cache_create() for struct se_session"
  81                                 " failed\n");
  82                 goto out;
  83         }
  84         se_ua_cache = kmem_cache_create("se_ua_cache",
  85                         sizeof(struct se_ua), __alignof__(struct se_ua),
  86                         0, NULL);
  87         if (!se_ua_cache) {
  88                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  89                 goto out_free_sess_cache;
  90         }
  91         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  92                         sizeof(struct t10_pr_registration),
  93                         __alignof__(struct t10_pr_registration), 0, NULL);
  94         if (!t10_pr_reg_cache) {
  95                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  96                                 " failed\n");
  97                 goto out_free_ua_cache;
  98         }
  99         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
 100                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
 101                         0, NULL);
 102         if (!t10_alua_lu_gp_cache) {
 103                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 104                                 " failed\n");
 105                 goto out_free_pr_reg_cache;
 106         }
 107         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 108                         sizeof(struct t10_alua_lu_gp_member),
 109                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 110         if (!t10_alua_lu_gp_mem_cache) {
 111                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 112                                 "cache failed\n");
 113                 goto out_free_lu_gp_cache;
 114         }
 115         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 116                         sizeof(struct t10_alua_tg_pt_gp),
 117                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 118         if (!t10_alua_tg_pt_gp_cache) {
 119                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 120                                 "cache failed\n");
 121                 goto out_free_lu_gp_mem_cache;
 122         }
 123         t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
 124                         "t10_alua_tg_pt_gp_mem_cache",
 125                         sizeof(struct t10_alua_tg_pt_gp_member),
 126                         __alignof__(struct t10_alua_tg_pt_gp_member),
 127                         0, NULL);
 128         if (!t10_alua_tg_pt_gp_mem_cache) {
 129                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 130                                 "mem_t failed\n");
 131                 goto out_free_tg_pt_gp_cache;
 132         }
 133         t10_alua_lba_map_cache = kmem_cache_create(
 134                         "t10_alua_lba_map_cache",
 135                         sizeof(struct t10_alua_lba_map),
 136                         __alignof__(struct t10_alua_lba_map), 0, NULL);
 137         if (!t10_alua_lba_map_cache) {
 138                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
 139                                 "cache failed\n");
 140                 goto out_free_tg_pt_gp_mem_cache;
 141         }
 142         t10_alua_lba_map_mem_cache = kmem_cache_create(
 143                         "t10_alua_lba_map_mem_cache",
 144                         sizeof(struct t10_alua_lba_map_member),
 145                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
 146         if (!t10_alua_lba_map_mem_cache) {
 147                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
 148                                 "cache failed\n");
 149                 goto out_free_lba_map_cache;
 150         }
 151
 152         target_completion_wq = alloc_workqueue("target_completion",
 153                                                WQ_MEM_RECLAIM, 0);
 154         if (!target_completion_wq)
 155                 goto out_free_lba_map_mem_cache;
 156
 157         return 0;
 158
 159 out_free_lba_map_mem_cache:
 160         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 161 out_free_lba_map_cache:
 162         kmem_cache_destroy(t10_alua_lba_map_cache);
 163 out_free_tg_pt_gp_mem_cache:
 164         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 165 out_free_tg_pt_gp_cache:
 166         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 167 out_free_lu_gp_mem_cache:
 168         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 169 out_free_lu_gp_cache:
 170         kmem_cache_destroy(t10_alua_lu_gp_cache);
 171 out_free_pr_reg_cache:
 172         kmem_cache_destroy(t10_pr_reg_cache);
 173 out_free_ua_cache:
 174         kmem_cache_destroy(se_ua_cache);
 175 out_free_sess_cache:
 176         kmem_cache_destroy(se_sess_cache);
 177 out:
 178         return -ENOMEM;
 179 }
 180
 181 void release_se_kmem_caches(void)
 182 {
 183         destroy_workqueue(target_completion_wq);
 184         kmem_cache_destroy(se_sess_cache);
 185         kmem_cache_destroy(se_ua_cache);
 186         kmem_cache_destroy(t10_pr_reg_cache);
 187         kmem_cache_destroy(t10_alua_lu_gp_cache);
 188         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 189         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 190         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 191         kmem_cache_destroy(t10_alua_lba_map_cache);
 192         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 193 }
 194
 195 /* This code ensures unique mib indexes are handed out. */
 196 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 197 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 198
 199 /*
 200  * Allocate a new row index for the entry type specified
 201  */
 202 u32 scsi_get_new_index(scsi_index_t type)
 203 {
 204         u32 new_index;
 205
 206         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 207
 208         spin_lock(&scsi_mib_index_lock);
 209         new_index = ++scsi_mib_index[type];
 210         spin_unlock(&scsi_mib_index_lock);
 211
 212         return new_index;
 213 }
 214
 215 void transport_subsystem_check_init(void)
 216 {
 217         int ret;
 218         static int sub_api_initialized;
 219
 220         if (sub_api_initialized)
 221                 return;
 222
 223         ret = request_module("target_core_iblock");
 224         if (ret != 0)
 225                 pr_err("Unable to load target_core_iblock\n");
 226
 227         ret = request_module("target_core_file");
 228         if (ret != 0)
 229                 pr_err("Unable to load target_core_file\n");
 230
 231         ret = request_module("target_core_pscsi");
 232         if (ret != 0)
 233                 pr_err("Unable to load target_core_pscsi\n");
 234
 235         sub_api_initialized = 1;
 236 }
 237
 238 struct se_session *transport_init_session(void)
 239 {
 240         struct se_session *se_sess;
 241
 242         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 243         if (!se_sess) {
 244                 pr_err("Unable to allocate struct se_session from"
 245                                 " se_sess_cache\n");
 246                 return ERR_PTR(-ENOMEM);
 247         }
 248         INIT_LIST_HEAD(&se_sess->sess_list);
 249         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 250         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 251         INIT_LIST_HEAD(&se_sess->sess_wait_list);
 252         spin_lock_init(&se_sess->sess_cmd_lock);
 253         kref_init(&se_sess->sess_kref);
 254
 255         return se_sess;
 256 }
 257 EXPORT_SYMBOL(transport_init_session);
 258
 259 int transport_alloc_session_tags(struct se_session *se_sess,
 260                                  unsigned int tag_num, unsigned int tag_size)
 261 {
 262         int rc;
 263
 264         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
 265                                         GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
 266         if (!se_sess->sess_cmd_map) {
 267                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
 268                 if (!se_sess->sess_cmd_map) {
 269                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 270                         return -ENOMEM;
 271                 }
 272         }
 273
 274         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
 275         if (rc < 0) {
 276                 pr_err("Unable to init se_sess->sess_tag_pool,"
 277                         " tag_num: %u\n", tag_num);
 278                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 279                         vfree(se_sess->sess_cmd_map);
 280                 else
 281                         kfree(se_sess->sess_cmd_map);
 282                 se_sess->sess_cmd_map = NULL;
 283                 return -ENOMEM;
 284         }
 285
 286         return 0;
 287 }
 288 EXPORT_SYMBOL(transport_alloc_session_tags);
 289
 290 struct se_session *transport_init_session_tags(unsigned int tag_num,
 291                                                unsigned int tag_size)
 292 {
 293         struct se_session *se_sess;
 294         int rc;
 295
 296         se_sess = transport_init_session();
 297         if (IS_ERR(se_sess))
 298                 return se_sess;
 299
 300         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 301         if (rc < 0) {
 302                 transport_free_session(se_sess);
 303                 return ERR_PTR(-ENOMEM);
 304         }
 305
 306         return se_sess;
 307 }
 308 EXPORT_SYMBOL(transport_init_session_tags);
 309
 310 /*
 311  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 312  */
 313 void __transport_register_session(
 314         struct se_portal_group *se_tpg,
 315         struct se_node_acl *se_nacl,
 316         struct se_session *se_sess,
 317         void *fabric_sess_ptr)
 318 {
 319         unsigned char buf[PR_REG_ISID_LEN];
 320
 321         se_sess->se_tpg = se_tpg;
 322         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 323         /*
 324          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 325          *
 326          * Only set for struct se_session's that will actually be moving I/O.
 327          * eg: *NOT* discovery sessions.
 328          */
 329         if (se_nacl) {
 330                 /*
 331                  * If the fabric module supports an ISID based TransportID,
 332                  * save this value in binary from the fabric I_T Nexus now.
 333                  */
 334                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 335                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 336                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 337                                         &buf[0], PR_REG_ISID_LEN);
 338                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 339                 }
 340                 kref_get(&se_nacl->acl_kref);
 341
 342                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 343                 /*
 344                  * The se_nacl->nacl_sess pointer will be set to the
 345                  * last active I_T Nexus for each struct se_node_acl.
 346                  */
 347                 se_nacl->nacl_sess = se_sess;
 348
 349                 list_add_tail(&se_sess->sess_acl_list,
 350                               &se_nacl->acl_sess_list);
 351                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 352         }
 353         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 354
 355         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 356                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 357 }
 358 EXPORT_SYMBOL(__transport_register_session);
 359
 360 void transport_register_session(
 361         struct se_portal_group *se_tpg,
 362         struct se_node_acl *se_nacl,
 363         struct se_session *se_sess,
 364         void *fabric_sess_ptr)
 365 {
 366         unsigned long flags;
 367
 368         spin_lock_irqsave(&se_tpg->session_lock, flags);
 369         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 370         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 371 }
 372 EXPORT_SYMBOL(transport_register_session);
 373
 374 static void target_release_session(struct kref *kref)
 375 {
 376         struct se_session *se_sess = container_of(kref,
 377                         struct se_session, sess_kref);
 378         struct se_portal_group *se_tpg = se_sess->se_tpg;
 379
 380         se_tpg->se_tpg_tfo->close_session(se_sess);
 381 }
 382
 383 void target_get_session(struct se_session *se_sess)
 384 {
 385         kref_get(&se_sess->sess_kref);
 386 }
 387 EXPORT_SYMBOL(target_get_session);
 388
 389 void target_put_session(struct se_session *se_sess)
 390 {
 391         struct se_portal_group *tpg = se_sess->se_tpg;
 392
 393         if (tpg->se_tpg_tfo->put_session != NULL) {
 394                 tpg->se_tpg_tfo->put_session(se_sess);
 395                 return;
 396         }
 397         kref_put(&se_sess->sess_kref, target_release_session);
 398 }
 399 EXPORT_SYMBOL(target_put_session);
 400
 401 static void target_complete_nacl(struct kref *kref)
 402 {
 403         struct se_node_acl *nacl = container_of(kref,
 404                                 struct se_node_acl, acl_kref);
 405
 406         complete(&nacl->acl_free_comp);
 407 }
 408
 409 void target_put_nacl(struct se_node_acl *nacl)
 410 {
 411         kref_put(&nacl->acl_kref, target_complete_nacl);
 412 }
 413
 414 void transport_deregister_session_configfs(struct se_session *se_sess)
 415 {
 416         struct se_node_acl *se_nacl;
 417         unsigned long flags;
 418         /*
 419          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 420          */
 421         se_nacl = se_sess->se_node_acl;
 422         if (se_nacl) {
 423                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 424                 if (se_nacl->acl_stop == 0)
 425                         list_del(&se_sess->sess_acl_list);
 426                 /*
 427                  * If the session list is empty, then clear the pointer.
 428                  * Otherwise, set the struct se_session pointer from the tail
 429                  * element of the per struct se_node_acl active session list.
 430                  */
 431                 if (list_empty(&se_nacl->acl_sess_list))
 432                         se_nacl->nacl_sess = NULL;
 433                 else {
 434                         se_nacl->nacl_sess = container_of(
 435                                         se_nacl->acl_sess_list.prev,
 436                                         struct se_session, sess_acl_list);
 437                 }
 438                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 439         }
 440 }
 441 EXPORT_SYMBOL(transport_deregister_session_configfs);
 442
 443 void transport_free_session(struct se_session *se_sess)
 444 {
 445         if (se_sess->sess_cmd_map) {
 446                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 447                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 448                         vfree(se_sess->sess_cmd_map);
 449                 else
 450                         kfree(se_sess->sess_cmd_map);
 451         }
 452         kmem_cache_free(se_sess_cache, se_sess);
 453 }
 454 EXPORT_SYMBOL(transport_free_session);
 455
 456 void transport_deregister_session(struct se_session *se_sess)
 457 {
 458         struct se_portal_group *se_tpg = se_sess->se_tpg;
 459         struct target_core_fabric_ops *se_tfo;
 460         struct se_node_acl *se_nacl;
 461         unsigned long flags;
 462         bool comp_nacl = true;
 463
 464         if (!se_tpg) {
 465                 transport_free_session(se_sess);
 466                 return;
 467         }
 468         se_tfo = se_tpg->se_tpg_tfo;
 469
 470         spin_lock_irqsave(&se_tpg->session_lock, flags);
 471         list_del(&se_sess->sess_list);
 472         se_sess->se_tpg = NULL;
 473         se_sess->fabric_sess_ptr = NULL;
 474         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 475
 476         /*
 477          * Determine if we need to do extra work for this initiator node's
 478          * struct se_node_acl if it had been previously dynamically generated.
 479          */
 480         se_nacl = se_sess->se_node_acl;
 481
 482         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 483         if (se_nacl && se_nacl->dynamic_node_acl) {
 484                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 485                         list_del(&se_nacl->acl_list);
 486                         se_tpg->num_node_acls--;
 487                         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 488                         core_tpg_wait_for_nacl_pr_ref(se_nacl);
 489                         core_free_device_list_for_node(se_nacl, se_tpg);
 490                         se_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
 491
 492                         comp_nacl = false;
 493                         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 494                 }
 495         }
 496         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 497
 498         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 499                 se_tpg->se_tpg_tfo->get_fabric_name());
 500         /*
 501          * If last kref is dropping now for an explicit NodeACL, awake sleeping
 502          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 503          * removal context.
 504          */
 505         if (se_nacl && comp_nacl == true)
 506                 target_put_nacl(se_nacl);
 507
 508         transport_free_session(se_sess);
 509 }
 510 EXPORT_SYMBOL(transport_deregister_session);
 511
 512 /*
 513  * Called with cmd->t_state_lock held.
 514  */
 515 static void target_remove_from_state_list(struct se_cmd *cmd)
 516 {
 517         struct se_device *dev = cmd->se_dev;
 518         unsigned long flags;
 519
 520         if (!dev)
 521                 return;
 522
 523         if (cmd->transport_state & CMD_T_BUSY)
 524                 return;
 525
 526         spin_lock_irqsave(&dev->execute_task_lock, flags);
 527         if (cmd->state_active) {
 528                 list_del(&cmd->state_list);
 529                 cmd->state_active = false;
 530         }
 531         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 532 }
 533
 534 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 535                                     bool write_pending)
 536 {
 537         unsigned long flags;
 538
 539         spin_lock_irqsave(&cmd->t_state_lock, flags);
 540         if (write_pending)
 541                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 542
 543         if (remove_from_lists) {
 544                 target_remove_from_state_list(cmd);
 545
 546                 /*
 547                  * Clear struct se_cmd->se_lun before the handoff to FE.
 548                  */
 549                 cmd->se_lun = NULL;
 550         }
 551
 552         /*
 553          * Determine if frontend context caller is requesting the stopping of
 554          * this command for frontend exceptions.
 555          */
 556         if (cmd->transport_state & CMD_T_STOP) {
 557                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
 558                         __func__, __LINE__,
 559                         cmd->se_tfo->get_task_tag(cmd));
 560
 561                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 562
 563                 complete(&cmd->t_transport_stop_comp);
 564                 return 1;
 565         }
 566
 567         cmd->transport_state &= ~CMD_T_ACTIVE;
 568         if (remove_from_lists) {
 569                 /*
 570                  * Some fabric modules like tcm_loop can release
 571                  * their internally allocated I/O reference now and
 572                  * struct se_cmd now.
 573                  *
 574                  * Fabric modules are expected to return '1' here if the
 575                  * se_cmd being passed is released at this point,
 576                  * or zero if not being released.
 577                  */
 578                 if (cmd->se_tfo->check_stop_free != NULL) {
 579                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 580                         return cmd->se_tfo->check_stop_free(cmd);
 581                 }
 582         }
 583
 584         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 585         return 0;
 586 }
 587
 588 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 589 {
 590         return transport_cmd_check_stop(cmd, true, false);
 591 }
 592
 593 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 594 {
 595         struct se_lun *lun = cmd->se_lun;
 596
 597         if (!lun)
 598                 return;
 599
 600         if (cmpxchg(&cmd->lun_ref_active, true, false))
 601                 percpu_ref_put(&lun->lun_ref);
 602 }
 603
 604 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 605 {
 606         if (transport_cmd_check_stop_to_fabric(cmd))
 607                 return;
 608         if (remove)
 609                 transport_put_cmd(cmd);
 610 }
 611
 612 static void target_complete_failure_work(struct work_struct *work)
 613 {
 614         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 615
 616         transport_generic_request_failure(cmd,
 617                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 618 }
 619
 620 /*
 621  * Used when asking transport to copy Sense Data from the underlying
 622  * Linux/SCSI struct scsi_cmnd
 623  */
 624 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 625 {
 626         struct se_device *dev = cmd->se_dev;
 627
 628         WARN_ON(!cmd->se_lun);
 629
 630         if (!dev)
 631                 return NULL;
 632
 633         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 634                 return NULL;
 635
 636         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 637
 638         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 639                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 640         return cmd->sense_buffer;
 641 }
 642
 643 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 644 {
 645         struct se_device *dev = cmd->se_dev;
 646         int success = scsi_status == GOOD;
 647         unsigned long flags;
 648
 649         cmd->scsi_status = scsi_status;
 650
 651
 652         spin_lock_irqsave(&cmd->t_state_lock, flags);
 653         cmd->transport_state &= ~CMD_T_BUSY;
 654
 655         if (dev && dev->transport->transport_complete) {
 656                 dev->transport->transport_complete(cmd,
 657                                 cmd->t_data_sg,
 658                                 transport_get_sense_buffer(cmd));
 659                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 660                         success = 1;
 661         }
 662
 663         /*
 664          * See if we are waiting to complete for an exception condition.
 665          */
 666         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
 667                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 668                 complete(&cmd->task_stop_comp);
 669                 return;
 670         }
 671
 672         if (!success)
 673                 cmd->transport_state |= CMD_T_FAILED;
 674
 675         /*
 676          * Check for case where an explicit ABORT_TASK has been received
 677          * and transport_wait_for_tasks() will be waiting for completion..
 678          */
 679         if (cmd->transport_state & CMD_T_ABORTED &&
 680             cmd->transport_state & CMD_T_STOP) {
 681                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 682                 complete(&cmd->t_transport_stop_comp);
 683                 return;
 684         } else if (cmd->transport_state & CMD_T_FAILED) {
 685                 INIT_WORK(&cmd->work, target_complete_failure_work);
 686         } else {
 687                 INIT_WORK(&cmd->work, target_complete_ok_work);
 688         }
 689
 690         cmd->t_state = TRANSPORT_COMPLETE;
 691         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 692         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 693
 694         queue_work(target_completion_wq, &cmd->work);
 695 }
 696 EXPORT_SYMBOL(target_complete_cmd);
 697
 698 static void target_add_to_state_list(struct se_cmd *cmd)
 699 {
 700         struct se_device *dev = cmd->se_dev;
 701         unsigned long flags;
 702
 703         spin_lock_irqsave(&dev->execute_task_lock, flags);
 704         if (!cmd->state_active) {
 705                 list_add_tail(&cmd->state_list, &dev->state_list);
 706                 cmd->state_active = true;
 707         }
 708         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 709 }
 710
 711 /*
 712  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 713  */
 714 static void transport_write_pending_qf(struct se_cmd *cmd);
 715 static void transport_complete_qf(struct se_cmd *cmd);
 716
 717 void target_qf_do_work(struct work_struct *work)
 718 {
 719         struct se_device *dev = container_of(work, struct se_device,
 720                                         qf_work_queue);
 721         LIST_HEAD(qf_cmd_list);
 722         struct se_cmd *cmd, *cmd_tmp;
 723
 724         spin_lock_irq(&dev->qf_cmd_lock);
 725         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 726         spin_unlock_irq(&dev->qf_cmd_lock);
 727
 728         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 729                 list_del(&cmd->se_qf_node);
 730                 atomic_dec(&dev->dev_qf_count);
 731                 smp_mb__after_atomic_dec();
 732
 733                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 734                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 735                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 736                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 737                         : "UNKNOWN");
 738
 739                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 740                         transport_write_pending_qf(cmd);
 741                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 742                         transport_complete_qf(cmd);
 743         }
 744 }
 745
 746 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 747 {
 748         switch (cmd->data_direction) {
 749         case DMA_NONE:
 750                 return "NONE";
 751         case DMA_FROM_DEVICE:
 752                 return "READ";
 753         case DMA_TO_DEVICE:
 754                 return "WRITE";
 755         case DMA_BIDIRECTIONAL:
 756                 return "BIDI";
 757         default:
 758                 break;
 759         }
 760
 761         return "UNKNOWN";
 762 }
 763
 764 void transport_dump_dev_state(
 765         struct se_device *dev,
 766         char *b,
 767         int *bl)
 768 {
 769         *bl += sprintf(b + *bl, "Status: ");
 770         if (dev->export_count)
 771                 *bl += sprintf(b + *bl, "ACTIVATED");
 772         else
 773                 *bl += sprintf(b + *bl, "DEACTIVATED");
 774
 775         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 776         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 777                 dev->dev_attrib.block_size,
 778                 dev->dev_attrib.hw_max_sectors);
 779         *bl += sprintf(b + *bl, "        ");
 780 }
 781
 782 void transport_dump_vpd_proto_id(
 783         struct t10_vpd *vpd,
 784         unsigned char *p_buf,
 785         int p_buf_len)
 786 {
 787         unsigned char buf[VPD_TMP_BUF_SIZE];
 788         int len;
 789
 790         memset(buf, 0, VPD_TMP_BUF_SIZE);
 791         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 792
 793         switch (vpd->protocol_identifier) {
 794         case 0x00:
 795                 sprintf(buf+len, "Fibre Channel\n");
 796                 break;
 797         case 0x10:
 798                 sprintf(buf+len, "Parallel SCSI\n");
 799                 break;
 800         case 0x20:
 801                 sprintf(buf+len, "SSA\n");
 802                 break;
 803         case 0x30:
 804                 sprintf(buf+len, "IEEE 1394\n");
 805                 break;
 806         case 0x40:
 807                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 808                                 " Protocol\n");
 809                 break;
 810         case 0x50:
 811                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 812                 break;
 813         case 0x60:
 814                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 815                 break;
 816         case 0x70:
 817                 sprintf(buf+len, "Automation/Drive Interface Transport"
 818                                 " Protocol\n");
 819                 break;
 820         case 0x80:
 821                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 822                 break;
 823         default:
 824                 sprintf(buf+len, "Unknown 0x%02x\n",
 825                                 vpd->protocol_identifier);
 826                 break;
 827         }
 828
 829         if (p_buf)
 830                 strncpy(p_buf, buf, p_buf_len);
 831         else
 832                 pr_debug("%s", buf);
 833 }
 834
 835 void
 836 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 837 {
 838         /*
 839          * Check if the Protocol Identifier Valid (PIV) bit is set..
 840          *
 841          * from spc3r23.pdf section 7.5.1
 842          */
 843          if (page_83[1] & 0x80) {
 844                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 845                 vpd->protocol_identifier_set = 1;
 846                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 847         }
 848 }
 849 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 850
 851 int transport_dump_vpd_assoc(
 852         struct t10_vpd *vpd,
 853         unsigned char *p_buf,
 854         int p_buf_len)
 855 {
 856         unsigned char buf[VPD_TMP_BUF_SIZE];
 857         int ret = 0;
 858         int len;
 859
 860         memset(buf, 0, VPD_TMP_BUF_SIZE);
 861         len = sprintf(buf, "T10 VPD Identifier Association: ");
 862
 863         switch (vpd->association) {
 864         case 0x00:
 865                 sprintf(buf+len, "addressed logical unit\n");
 866                 break;
 867         case 0x10:
 868                 sprintf(buf+len, "target port\n");
 869                 break;
 870         case 0x20:
 871                 sprintf(buf+len, "SCSI target device\n");
 872                 break;
 873         default:
 874                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 875                 ret = -EINVAL;
 876                 break;
 877         }
 878
 879         if (p_buf)
 880                 strncpy(p_buf, buf, p_buf_len);
 881         else
 882                 pr_debug("%s", buf);
 883
 884         return ret;
 885 }
 886
 887 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 888 {
 889         /*
 890          * The VPD identification association..
 891          *
 892          * from spc3r23.pdf Section 7.6.3.1 Table 297
 893          */
 894         vpd->association = (page_83[1] & 0x30);
 895         return transport_dump_vpd_assoc(vpd, NULL, 0);
 896 }
 897 EXPORT_SYMBOL(transport_set_vpd_assoc);
 898
 899 int transport_dump_vpd_ident_type(
 900         struct t10_vpd *vpd,
 901         unsigned char *p_buf,
 902         int p_buf_len)
 903 {
 904         unsigned char buf[VPD_TMP_BUF_SIZE];
 905         int ret = 0;
 906         int len;
 907
 908         memset(buf, 0, VPD_TMP_BUF_SIZE);
 909         len = sprintf(buf, "T10 VPD Identifier Type: ");
 910
 911         switch (vpd->device_identifier_type) {
 912         case 0x00:
 913                 sprintf(buf+len, "Vendor specific\n");
 914                 break;
 915         case 0x01:
 916                 sprintf(buf+len, "T10 Vendor ID based\n");
 917                 break;
 918         case 0x02:
 919                 sprintf(buf+len, "EUI-64 based\n");
 920                 break;
 921         case 0x03:
 922                 sprintf(buf+len, "NAA\n");
 923                 break;
 924         case 0x04:
 925                 sprintf(buf+len, "Relative target port identifier\n");
 926                 break;
 927         case 0x08:
 928                 sprintf(buf+len, "SCSI name string\n");
 929                 break;
 930         default:
 931                 sprintf(buf+len, "Unsupported: 0x%02x\n",
 932                                 vpd->device_identifier_type);
 933                 ret = -EINVAL;
 934                 break;
 935         }
 936
 937         if (p_buf) {
 938                 if (p_buf_len < strlen(buf)+1)
 939                         return -EINVAL;
 940                 strncpy(p_buf, buf, p_buf_len);
 941         } else {
 942                 pr_debug("%s", buf);
 943         }
 944
 945         return ret;
 946 }
 947
 948 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
 949 {
 950         /*
 951          * The VPD identifier type..
 952          *
 953          * from spc3r23.pdf Section 7.6.3.1 Table 298
 954          */
 955         vpd->device_identifier_type = (page_83[1] & 0x0f);
 956         return transport_dump_vpd_ident_type(vpd, NULL, 0);
 957 }
 958 EXPORT_SYMBOL(transport_set_vpd_ident_type);
 959
 960 int transport_dump_vpd_ident(
 961         struct t10_vpd *vpd,
 962         unsigned char *p_buf,
 963         int p_buf_len)
 964 {
 965         unsigned char buf[VPD_TMP_BUF_SIZE];
 966         int ret = 0;
 967
 968         memset(buf, 0, VPD_TMP_BUF_SIZE);
 969
 970         switch (vpd->device_identifier_code_set) {
 971         case 0x01: /* Binary */
 972                 snprintf(buf, sizeof(buf),
 973                         "T10 VPD Binary Device Identifier: %s\n",
 974                         &vpd->device_identifier[0]);
 975                 break;
 976         case 0x02: /* ASCII */
 977                 snprintf(buf, sizeof(buf),
 978                         "T10 VPD ASCII Device Identifier: %s\n",
 979                         &vpd->device_identifier[0]);
 980                 break;
 981         case 0x03: /* UTF-8 */
 982                 snprintf(buf, sizeof(buf),
 983                         "T10 VPD UTF-8 Device Identifier: %s\n",
 984                         &vpd->device_identifier[0]);
 985                 break;
 986         default:
 987                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
 988                         " 0x%02x", vpd->device_identifier_code_set);
 989                 ret = -EINVAL;
 990                 break;
 991         }
 992
 993         if (p_buf)
 994                 strncpy(p_buf, buf, p_buf_len);
 995         else
 996                 pr_debug("%s", buf);
 997
 998         return ret;
 999 }
1000
1001 int
1002 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1003 {
1004         static const char hex_str[] = "0123456789abcdef";
1005         int j = 0, i = 4; /* offset to start of the identifier */
1006
1007         /*
1008          * The VPD Code Set (encoding)
1009          *
1010          * from spc3r23.pdf Section 7.6.3.1 Table 296
1011          */
1012         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1013         switch (vpd->device_identifier_code_set) {
1014         case 0x01: /* Binary */
1015                 vpd->device_identifier[j++] =
1016                                 hex_str[vpd->device_identifier_type];
1017                 while (i < (4 + page_83[3])) {
1018                         vpd->device_identifier[j++] =
1019                                 hex_str[(page_83[i] & 0xf0) >> 4];
1020                         vpd->device_identifier[j++] =
1021                                 hex_str[page_83[i] & 0x0f];
1022                         i++;
1023                 }
1024                 break;
1025         case 0x02: /* ASCII */
1026         case 0x03: /* UTF-8 */
1027                 while (i < (4 + page_83[3]))
1028                         vpd->device_identifier[j++] = page_83[i++];
1029                 break;
1030         default:
1031                 break;
1032         }
1033
1034         return transport_dump_vpd_ident(vpd, NULL, 0);
1035 }
1036 EXPORT_SYMBOL(transport_set_vpd_ident);
1037
1038 sense_reason_t
1039 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1040 {
1041         struct se_device *dev = cmd->se_dev;
1042
1043         if (cmd->unknown_data_length) {
1044                 cmd->data_length = size;
1045         } else if (size != cmd->data_length) {
1046                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1047                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1048                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1049                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1050
1051                 if (cmd->data_direction == DMA_TO_DEVICE) {
1052                         pr_err("Rejecting underflow/overflow"
1053                                         " WRITE data\n");
1054                         return TCM_INVALID_CDB_FIELD;
1055                 }
1056                 /*
1057                  * Reject READ_* or WRITE_* with overflow/underflow for
1058                  * type SCF_SCSI_DATA_CDB.
1059                  */
1060                 if (dev->dev_attrib.block_size != 512)  {
1061                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1062                                 " CDB on non 512-byte sector setup subsystem"
1063                                 " plugin: %s\n", dev->transport->name);
1064                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1065                         return TCM_INVALID_CDB_FIELD;
1066                 }
1067                 /*
1068                  * For the overflow case keep the existing fabric provided
1069                  * ->data_length.  Otherwise for the underflow case, reset
1070                  * ->data_length to the smaller SCSI expected data transfer
1071                  * length.
1072                  */
1073                 if (size > cmd->data_length) {
1074                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1075                         cmd->residual_count = (size - cmd->data_length);
1076                 } else {
1077                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1078                         cmd->residual_count = (cmd->data_length - size);
1079                         cmd->data_length = size;
1080                 }
1081         }
1082
1083         return 0;
1084
1085 }
1086
1087 /*
1088  * Used by fabric modules containing a local struct se_cmd within their
1089  * fabric dependent per I/O descriptor.
1090  */
1091 void transport_init_se_cmd(
1092         struct se_cmd *cmd,
1093         struct target_core_fabric_ops *tfo,
1094         struct se_session *se_sess,
1095         u32 data_length,
1096         int data_direction,
1097         int task_attr,
1098         unsigned char *sense_buffer)
1099 {
1100         INIT_LIST_HEAD(&cmd->se_delayed_node);
1101         INIT_LIST_HEAD(&cmd->se_qf_node);
1102         INIT_LIST_HEAD(&cmd->se_cmd_list);
1103         INIT_LIST_HEAD(&cmd->state_list);
1104         init_completion(&cmd->t_transport_stop_comp);
1105         init_completion(&cmd->cmd_wait_comp);
1106         init_completion(&cmd->task_stop_comp);
1107         spin_lock_init(&cmd->t_state_lock);
1108         cmd->transport_state = CMD_T_DEV_ACTIVE;
1109
1110         cmd->se_tfo = tfo;
1111         cmd->se_sess = se_sess;
1112         cmd->data_length = data_length;
1113         cmd->data_direction = data_direction;
1114         cmd->sam_task_attr = task_attr;
1115         cmd->sense_buffer = sense_buffer;
1116
1117         cmd->state_active = false;
1118 }
1119 EXPORT_SYMBOL(transport_init_se_cmd);
1120
1121 static sense_reason_t
1122 transport_check_alloc_task_attr(struct se_cmd *cmd)
1123 {
1124         struct se_device *dev = cmd->se_dev;
1125
1126         /*
1127          * Check if SAM Task Attribute emulation is enabled for this
1128          * struct se_device storage object
1129          */
1130         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1131                 return 0;
1132
1133         if (cmd->sam_task_attr == MSG_ACA_TAG) {
1134                 pr_debug("SAM Task Attribute ACA"
1135                         " emulation is not supported\n");
1136                 return TCM_INVALID_CDB_FIELD;
1137         }
1138         /*
1139          * Used to determine when ORDERED commands should go from
1140          * Dormant to Active status.
1141          */
1142         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1143         smp_mb__after_atomic_inc();
1144         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1145                         cmd->se_ordered_id, cmd->sam_task_attr,
1146                         dev->transport->name);
1147         return 0;
1148 }
1149
1150 sense_reason_t
1151 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1152 {
1153         struct se_device *dev = cmd->se_dev;
1154         sense_reason_t ret;
1155
1156         /*
1157          * Ensure that the received CDB is less than the max (252 + 8) bytes
1158          * for VARIABLE_LENGTH_CMD
1159          */
1160         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1161                 pr_err("Received SCSI CDB with command_size: %d that"
1162                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1163                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1164                 return TCM_INVALID_CDB_FIELD;
1165         }
1166         /*
1167          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1168          * allocate the additional extended CDB buffer now..  Otherwise
1169          * setup the pointer from __t_task_cdb to t_task_cdb.
1170          */
1171         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1172                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1173                                                 GFP_KERNEL);
1174                 if (!cmd->t_task_cdb) {
1175                         pr_err("Unable to allocate cmd->t_task_cdb"
1176                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1177                                 scsi_command_size(cdb),
1178                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1179                         return TCM_OUT_OF_RESOURCES;
1180                 }
1181         } else
1182                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1183         /*
1184          * Copy the original CDB into cmd->
1185          */
1186         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1187
1188         trace_target_sequencer_start(cmd);
1189
1190         /*
1191          * Check for an existing UNIT ATTENTION condition
1192          */
1193         ret = target_scsi3_ua_check(cmd);
1194         if (ret)
1195                 return ret;
1196
1197         ret = target_alua_state_check(cmd);
1198         if (ret)
1199                 return ret;
1200
1201         ret = target_check_reservation(cmd);
1202         if (ret) {
1203                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1204                 return ret;
1205         }
1206
1207         ret = dev->transport->parse_cdb(cmd);
1208         if (ret)
1209                 return ret;
1210
1211         ret = transport_check_alloc_task_attr(cmd);
1212         if (ret)
1213                 return ret;
1214
1215         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1216
1217         spin_lock(&cmd->se_lun->lun_sep_lock);
1218         if (cmd->se_lun->lun_sep)
1219                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1220         spin_unlock(&cmd->se_lun->lun_sep_lock);
1221         return 0;
1222 }
1223 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1224
1225 /*
1226  * Used by fabric module frontends to queue tasks directly.
1227  * Many only be used from process context only
1228  */
1229 int transport_handle_cdb_direct(
1230         struct se_cmd *cmd)
1231 {
1232         sense_reason_t ret;
1233
1234         if (!cmd->se_lun) {
1235                 dump_stack();
1236                 pr_err("cmd->se_lun is NULL\n");
1237                 return -EINVAL;
1238         }
1239         if (in_interrupt()) {
1240                 dump_stack();
1241                 pr_err("transport_generic_handle_cdb cannot be called"
1242                                 " from interrupt context\n");
1243                 return -EINVAL;
1244         }
1245         /*
1246          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1247          * outstanding descriptors are handled correctly during shutdown via
1248          * transport_wait_for_tasks()
1249          *
1250          * Also, we don't take cmd->t_state_lock here as we only expect
1251          * this to be called for initial descriptor submission.
1252          */
1253         cmd->t_state = TRANSPORT_NEW_CMD;
1254         cmd->transport_state |= CMD_T_ACTIVE;
1255
1256         /*
1257          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1258          * so follow TRANSPORT_NEW_CMD processing thread context usage
1259          * and call transport_generic_request_failure() if necessary..
1260          */
1261         ret = transport_generic_new_cmd(cmd);
1262         if (ret)
1263                 transport_generic_request_failure(cmd, ret);
1264         return 0;
1265 }
1266 EXPORT_SYMBOL(transport_handle_cdb_direct);
1267
1268 sense_reason_t
1269 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1270                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1271 {
1272         if (!sgl || !sgl_count)
1273                 return 0;
1274
1275         /*
1276          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1277          * scatterlists already have been set to follow what the fabric
1278          * passes for the original expected data transfer length.
1279          */
1280         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1281                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1282                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1283                 return TCM_INVALID_CDB_FIELD;
1284         }
1285
1286         cmd->t_data_sg = sgl;
1287         cmd->t_data_nents = sgl_count;
1288
1289         if (sgl_bidi && sgl_bidi_count) {
1290                 cmd->t_bidi_data_sg = sgl_bidi;
1291                 cmd->t_bidi_data_nents = sgl_bidi_count;
1292         }
1293         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1294         return 0;
1295 }
1296
1297 /*
1298  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1299  *                       se_cmd + use pre-allocated SGL memory.
1300  *
1301  * @se_cmd: command descriptor to submit
1302  * @se_sess: associated se_sess for endpoint
1303  * @cdb: pointer to SCSI CDB
1304  * @sense: pointer to SCSI sense buffer
1305  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1306  * @data_length: fabric expected data transfer length
1307  * @task_addr: SAM task attribute
1308  * @data_dir: DMA data direction
1309  * @flags: flags for command submission from target_sc_flags_tables
1310  * @sgl: struct scatterlist memory for unidirectional mapping
1311  * @sgl_count: scatterlist count for unidirectional mapping
1312  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1313  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1314  * @sgl_prot: struct scatterlist memory protection information
1315  * @sgl_prot_count: scatterlist count for protection information
1316  *
1317  * Returns non zero to signal active I/O shutdown failure.  All other
1318  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1319  * but still return zero here.
1320  *
1321  * This may only be called from process context, and also currently
1322  * assumes internal allocation of fabric payload buffer by target-core.
1323  */
1324 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1325                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1326                 u32 data_length, int task_attr, int data_dir, int flags,
1327                 struct scatterlist *sgl, u32 sgl_count,
1328                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1329                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1330 {
1331         struct se_portal_group *se_tpg;
1332         sense_reason_t rc;
1333         int ret;
1334
1335         se_tpg = se_sess->se_tpg;
1336         BUG_ON(!se_tpg);
1337         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1338         BUG_ON(in_interrupt());
1339         /*
1340          * Initialize se_cmd for target operation.  From this point
1341          * exceptions are handled by sending exception status via
1342          * target_core_fabric_ops->queue_status() callback
1343          */
1344         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1345                                 data_length, data_dir, task_attr, sense);
1346         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1347                 se_cmd->unknown_data_length = 1;
1348         /*
1349          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1350          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1351          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1352          * kref_put() to happen during fabric packet acknowledgement.
1353          */
1354         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1355         if (ret)
1356                 return ret;
1357         /*
1358          * Signal bidirectional data payloads to target-core
1359          */
1360         if (flags & TARGET_SCF_BIDI_OP)
1361                 se_cmd->se_cmd_flags |= SCF_BIDI;
1362         /*
1363          * Locate se_lun pointer and attach it to struct se_cmd
1364          */
1365         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1366         if (rc) {
1367                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1368                 target_put_sess_cmd(se_sess, se_cmd);
1369                 return 0;
1370         }
1371         /*
1372          * Save pointers for SGLs containing protection information,
1373          * if present.
1374          */
1375         if (sgl_prot_count) {
1376                 se_cmd->t_prot_sg = sgl_prot;
1377                 se_cmd->t_prot_nents = sgl_prot_count;
1378         }
1379
1380         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1381         if (rc != 0) {
1382                 transport_generic_request_failure(se_cmd, rc);
1383                 return 0;
1384         }
1385         /*
1386          * When a non zero sgl_count has been passed perform SGL passthrough
1387          * mapping for pre-allocated fabric memory instead of having target
1388          * core perform an internal SGL allocation..
1389          */
1390         if (sgl_count != 0) {
1391                 BUG_ON(!sgl);
1392
1393                 /*
1394                  * A work-around for tcm_loop as some userspace code via
1395                  * scsi-generic do not memset their associated read buffers,
1396                  * so go ahead and do that here for type non-data CDBs.  Also
1397                  * note that this is currently guaranteed to be a single SGL
1398                  * for this case by target core in target_setup_cmd_from_cdb()
1399                  * -> transport_generic_cmd_sequencer().
1400                  */
1401                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1402                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1403                         unsigned char *buf = NULL;
1404
1405                         if (sgl)
1406                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1407
1408                         if (buf) {
1409                                 memset(buf, 0, sgl->length);
1410                                 kunmap(sg_page(sgl));
1411                         }
1412                 }
1413
1414                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1415                                 sgl_bidi, sgl_bidi_count);
1416                 if (rc != 0) {
1417                         transport_generic_request_failure(se_cmd, rc);
1418                         return 0;
1419                 }
1420         }
1421
1422         /*
1423          * Check if we need to delay processing because of ALUA
1424          * Active/NonOptimized primary access state..
1425          */
1426         core_alua_check_nonop_delay(se_cmd);
1427
1428         transport_handle_cdb_direct(se_cmd);
1429         return 0;
1430 }
1431 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1432
1433 /*
1434  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1435  *
1436  * @se_cmd: command descriptor to submit
1437  * @se_sess: associated se_sess for endpoint
1438  * @cdb: pointer to SCSI CDB
1439  * @sense: pointer to SCSI sense buffer
1440  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1441  * @data_length: fabric expected data transfer length
1442  * @task_addr: SAM task attribute
1443  * @data_dir: DMA data direction
1444  * @flags: flags for command submission from target_sc_flags_tables
1445  *
1446  * Returns non zero to signal active I/O shutdown failure.  All other
1447  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1448  * but still return zero here.
1449  *
1450  * This may only be called from process context, and also currently
1451  * assumes internal allocation of fabric payload buffer by target-core.
1452  *
1453  * It also assumes interal target core SGL memory allocation.
1454  */
1455 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1456                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1457                 u32 data_length, int task_attr, int data_dir, int flags)
1458 {
1459         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1460                         unpacked_lun, data_length, task_attr, data_dir,
1461                         flags, NULL, 0, NULL, 0, NULL, 0);
1462 }
1463 EXPORT_SYMBOL(target_submit_cmd);
1464
1465 static void target_complete_tmr_failure(struct work_struct *work)
1466 {
1467         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1468
1469         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1470         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1471
1472         transport_cmd_check_stop_to_fabric(se_cmd);
1473 }
1474
1475 /**
1476  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1477  *                     for TMR CDBs
1478  *
1479  * @se_cmd: command descriptor to submit
1480  * @se_sess: associated se_sess for endpoint
1481  * @sense: pointer to SCSI sense buffer
1482  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1483  * @fabric_context: fabric context for TMR req
1484  * @tm_type: Type of TM request
1485  * @gfp: gfp type for caller
1486  * @tag: referenced task tag for TMR_ABORT_TASK
1487  * @flags: submit cmd flags
1488  *
1489  * Callable from all contexts.
1490  **/
1491
1492 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1493                 unsigned char *sense, u32 unpacked_lun,
1494                 void *fabric_tmr_ptr, unsigned char tm_type,
1495                 gfp_t gfp, unsigned int tag, int flags)
1496 {
1497         struct se_portal_group *se_tpg;
1498         int ret;
1499
1500         se_tpg = se_sess->se_tpg;
1501         BUG_ON(!se_tpg);
1502
1503         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1504                               0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1505         /*
1506          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1507          * allocation failure.
1508          */
1509         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1510         if (ret < 0)
1511                 return -ENOMEM;
1512
1513         if (tm_type == TMR_ABORT_TASK)
1514                 se_cmd->se_tmr_req->ref_task_tag = tag;
1515
1516         /* See target_submit_cmd for commentary */
1517         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1518         if (ret) {
1519                 core_tmr_release_req(se_cmd->se_tmr_req);
1520                 return ret;
1521         }
1522
1523         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1524         if (ret) {
1525                 /*
1526                  * For callback during failure handling, push this work off
1527                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1528                  */
1529                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1530                 schedule_work(&se_cmd->work);
1531                 return 0;
1532         }
1533         transport_generic_handle_tmr(se_cmd);
1534         return 0;
1535 }
1536 EXPORT_SYMBOL(target_submit_tmr);
1537
1538 /*
1539  * If the cmd is active, request it to be stopped and sleep until it
1540  * has completed.
1541  */
1542 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1543 {
1544         bool was_active = false;
1545
1546         if (cmd->transport_state & CMD_T_BUSY) {
1547                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1548                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1549
1550                 pr_debug("cmd %p waiting to complete\n", cmd);
1551                 wait_for_completion(&cmd->task_stop_comp);
1552                 pr_debug("cmd %p stopped successfully\n", cmd);
1553
1554                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1555                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1556                 cmd->transport_state &= ~CMD_T_BUSY;
1557                 was_active = true;
1558         }
1559
1560         return was_active;
1561 }
1562
1563 /*
1564  * Handle SAM-esque emulation for generic transport request failures.
1565  */
1566 void transport_generic_request_failure(struct se_cmd *cmd,
1567                 sense_reason_t sense_reason)
1568 {
1569         int ret = 0;
1570
1571         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1572                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1573                 cmd->t_task_cdb[0]);
1574         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1575                 cmd->se_tfo->get_cmd_state(cmd),
1576                 cmd->t_state, sense_reason);
1577         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1578                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1579                 (cmd->transport_state & CMD_T_STOP) != 0,
1580                 (cmd->transport_state & CMD_T_SENT) != 0);
1581
1582         /*
1583          * For SAM Task Attribute emulation for failed struct se_cmd
1584          */
1585         transport_complete_task_attr(cmd);
1586         /*
1587          * Handle special case for COMPARE_AND_WRITE failure, where the
1588          * callback is expected to drop the per device ->caw_mutex.
1589          */
1590         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1591              cmd->transport_complete_callback)
1592                 cmd->transport_complete_callback(cmd);
1593
1594         switch (sense_reason) {
1595         case TCM_NON_EXISTENT_LUN:
1596         case TCM_UNSUPPORTED_SCSI_OPCODE:
1597         case TCM_INVALID_CDB_FIELD:
1598         case TCM_INVALID_PARAMETER_LIST:
1599         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1600         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1601         case TCM_UNKNOWN_MODE_PAGE:
1602         case TCM_WRITE_PROTECTED:
1603         case TCM_ADDRESS_OUT_OF_RANGE:
1604         case TCM_CHECK_CONDITION_ABORT_CMD:
1605         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1606         case TCM_CHECK_CONDITION_NOT_READY:
1607                 break;
1608         case TCM_OUT_OF_RESOURCES:
1609                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1610                 break;
1611         case TCM_RESERVATION_CONFLICT:
1612                 /*
1613                  * No SENSE Data payload for this case, set SCSI Status
1614                  * and queue the response to $FABRIC_MOD.
1615                  *
1616                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1617                  */
1618                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1619                 /*
1620                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1621                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1622                  * CONFLICT STATUS.
1623                  *
1624                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1625                  */
1626                 if (cmd->se_sess &&
1627                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1628                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1629                                 cmd->orig_fe_lun, 0x2C,
1630                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1631
1632                 trace_target_cmd_complete(cmd);
1633                 ret = cmd->se_tfo-> queue_status(cmd);
1634                 if (ret == -EAGAIN || ret == -ENOMEM)
1635                         goto queue_full;
1636                 goto check_stop;
1637         default:
1638                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1639                         cmd->t_task_cdb[0], sense_reason);
1640                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1641                 break;
1642         }
1643
1644         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1645         if (ret == -EAGAIN || ret == -ENOMEM)
1646                 goto queue_full;
1647
1648 check_stop:
1649         transport_lun_remove_cmd(cmd);
1650         if (!transport_cmd_check_stop_to_fabric(cmd))
1651                 ;
1652         return;
1653
1654 queue_full:
1655         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1656         transport_handle_queue_full(cmd, cmd->se_dev);
1657 }
1658 EXPORT_SYMBOL(transport_generic_request_failure);
1659
1660 void __target_execute_cmd(struct se_cmd *cmd)
1661 {
1662         sense_reason_t ret;
1663
1664         if (cmd->execute_cmd) {
1665                 ret = cmd->execute_cmd(cmd);
1666                 if (ret) {
1667                         spin_lock_irq(&cmd->t_state_lock);
1668                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1669                         spin_unlock_irq(&cmd->t_state_lock);
1670
1671                         transport_generic_request_failure(cmd, ret);
1672                 }
1673         }
1674 }
1675
1676 static bool target_handle_task_attr(struct se_cmd *cmd)
1677 {
1678         struct se_device *dev = cmd->se_dev;
1679
1680         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1681                 return false;
1682
1683         /*
1684          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1685          * to allow the passed struct se_cmd list of tasks to the front of the list.
1686          */
1687         switch (cmd->sam_task_attr) {
1688         case MSG_HEAD_TAG:
1689                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1690                          "se_ordered_id: %u\n",
1691                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1692                 return false;
1693         case MSG_ORDERED_TAG:
1694                 atomic_inc(&dev->dev_ordered_sync);
1695                 smp_mb__after_atomic_inc();
1696
1697                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1698                          " se_ordered_id: %u\n",
1699                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1700
1701                 /*
1702                  * Execute an ORDERED command if no other older commands
1703                  * exist that need to be completed first.
1704                  */
1705                 if (!atomic_read(&dev->simple_cmds))
1706                         return false;
1707                 break;
1708         default:
1709                 /*
1710                  * For SIMPLE and UNTAGGED Task Attribute commands
1711                  */
1712                 atomic_inc(&dev->simple_cmds);
1713                 smp_mb__after_atomic_inc();
1714                 break;
1715         }
1716
1717         if (atomic_read(&dev->dev_ordered_sync) == 0)
1718                 return false;
1719
1720         spin_lock(&dev->delayed_cmd_lock);
1721         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1722         spin_unlock(&dev->delayed_cmd_lock);
1723
1724         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1725                 " delayed CMD list, se_ordered_id: %u\n",
1726                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1727                 cmd->se_ordered_id);
1728         return true;
1729 }
1730
1731 void target_execute_cmd(struct se_cmd *cmd)
1732 {
1733         /*
1734          * If the received CDB has aleady been aborted stop processing it here.
1735          */
1736         if (transport_check_aborted_status(cmd, 1))
1737                 return;
1738
1739         /*
1740          * Determine if frontend context caller is requesting the stopping of
1741          * this command for frontend exceptions.
1742          */
1743         spin_lock_irq(&cmd->t_state_lock);
1744         if (cmd->transport_state & CMD_T_STOP) {
1745                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1746                         __func__, __LINE__,
1747                         cmd->se_tfo->get_task_tag(cmd));
1748
1749                 spin_unlock_irq(&cmd->t_state_lock);
1750                 complete(&cmd->t_transport_stop_comp);
1751                 return;
1752         }
1753
1754         cmd->t_state = TRANSPORT_PROCESSING;
1755         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1756         spin_unlock_irq(&cmd->t_state_lock);
1757
1758         if (target_handle_task_attr(cmd)) {
1759                 spin_lock_irq(&cmd->t_state_lock);
1760                 cmd->transport_state &= ~CMD_T_BUSY|CMD_T_SENT;
1761                 spin_unlock_irq(&cmd->t_state_lock);
1762                 return;
1763         }
1764
1765         __target_execute_cmd(cmd);
1766 }
1767 EXPORT_SYMBOL(target_execute_cmd);
1768
1769 /*
1770  * Process all commands up to the last received ORDERED task attribute which
1771  * requires another blocking boundary
1772  */
1773 static void target_restart_delayed_cmds(struct se_device *dev)
1774 {
1775         for (;;) {
1776                 struct se_cmd *cmd;
1777
1778                 spin_lock(&dev->delayed_cmd_lock);
1779                 if (list_empty(&dev->delayed_cmd_list)) {
1780                         spin_unlock(&dev->delayed_cmd_lock);
1781                         break;
1782                 }
1783
1784                 cmd = list_entry(dev->delayed_cmd_list.next,
1785                                  struct se_cmd, se_delayed_node);
1786                 list_del(&cmd->se_delayed_node);
1787                 spin_unlock(&dev->delayed_cmd_lock);
1788
1789                 __target_execute_cmd(cmd);
1790
1791                 if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1792                         break;
1793         }
1794 }
1795
1796 /*
1797  * Called from I/O completion to determine which dormant/delayed
1798  * and ordered cmds need to have their tasks added to the execution queue.
1799  */
1800 static void transport_complete_task_attr(struct se_cmd *cmd)
1801 {
1802         struct se_device *dev = cmd->se_dev;
1803
1804         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1805                 return;
1806
1807         if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1808                 atomic_dec(&dev->simple_cmds);
1809                 smp_mb__after_atomic_dec();
1810                 dev->dev_cur_ordered_id++;
1811                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1812                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1813                         cmd->se_ordered_id);
1814         } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1815                 dev->dev_cur_ordered_id++;
1816                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1817                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1818                         cmd->se_ordered_id);
1819         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1820                 atomic_dec(&dev->dev_ordered_sync);
1821                 smp_mb__after_atomic_dec();
1822
1823                 dev->dev_cur_ordered_id++;
1824                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1825                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1826         }
1827
1828         target_restart_delayed_cmds(dev);
1829 }
1830
1831 static void transport_complete_qf(struct se_cmd *cmd)
1832 {
1833         int ret = 0;
1834
1835         transport_complete_task_attr(cmd);
1836
1837         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1838                 trace_target_cmd_complete(cmd);
1839                 ret = cmd->se_tfo->queue_status(cmd);
1840                 if (ret)
1841                         goto out;
1842         }
1843
1844         switch (cmd->data_direction) {
1845         case DMA_FROM_DEVICE:
1846                 trace_target_cmd_complete(cmd);
1847                 ret = cmd->se_tfo->queue_data_in(cmd);
1848                 break;
1849         case DMA_TO_DEVICE:
1850                 if (cmd->se_cmd_flags & SCF_BIDI) {
1851                         ret = cmd->se_tfo->queue_data_in(cmd);
1852                         if (ret < 0)
1853                                 break;
1854                 }
1855                 /* Fall through for DMA_TO_DEVICE */
1856         case DMA_NONE:
1857                 trace_target_cmd_complete(cmd);
1858                 ret = cmd->se_tfo->queue_status(cmd);
1859                 break;
1860         default:
1861                 break;
1862         }
1863
1864 out:
1865         if (ret < 0) {
1866                 transport_handle_queue_full(cmd, cmd->se_dev);
1867                 return;
1868         }
1869         transport_lun_remove_cmd(cmd);
1870         transport_cmd_check_stop_to_fabric(cmd);
1871 }
1872
1873 static void transport_handle_queue_full(
1874         struct se_cmd *cmd,
1875         struct se_device *dev)
1876 {
1877         spin_lock_irq(&dev->qf_cmd_lock);
1878         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1879         atomic_inc(&dev->dev_qf_count);
1880         smp_mb__after_atomic_inc();
1881         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1882
1883         schedule_work(&cmd->se_dev->qf_work_queue);
1884 }
1885
1886 static void target_complete_ok_work(struct work_struct *work)
1887 {
1888         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1889         int ret;
1890
1891         /*
1892          * Check if we need to move delayed/dormant tasks from cmds on the
1893          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1894          * Attribute.
1895          */
1896         transport_complete_task_attr(cmd);
1897
1898         /*
1899          * Check to schedule QUEUE_FULL work, or execute an existing
1900          * cmd->transport_qf_callback()
1901          */
1902         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1903                 schedule_work(&cmd->se_dev->qf_work_queue);
1904
1905         /*
1906          * Check if we need to send a sense buffer from
1907          * the struct se_cmd in question.
1908          */
1909         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1910                 WARN_ON(!cmd->scsi_status);
1911                 ret = transport_send_check_condition_and_sense(
1912                                         cmd, 0, 1);
1913                 if (ret == -EAGAIN || ret == -ENOMEM)
1914                         goto queue_full;
1915
1916                 transport_lun_remove_cmd(cmd);
1917                 transport_cmd_check_stop_to_fabric(cmd);
1918                 return;
1919         }
1920         /*
1921          * Check for a callback, used by amongst other things
1922          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
1923          */
1924         if (cmd->transport_complete_callback) {
1925                 sense_reason_t rc;
1926
1927                 rc = cmd->transport_complete_callback(cmd);
1928                 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
1929                         return;
1930                 } else if (rc) {
1931                         ret = transport_send_check_condition_and_sense(cmd,
1932                                                 rc, 0);
1933                         if (ret == -EAGAIN || ret == -ENOMEM)
1934                                 goto queue_full;
1935
1936                         transport_lun_remove_cmd(cmd);
1937                         transport_cmd_check_stop_to_fabric(cmd);
1938                         return;
1939                 }
1940         }
1941
1942         switch (cmd->data_direction) {
1943         case DMA_FROM_DEVICE:
1944                 spin_lock(&cmd->se_lun->lun_sep_lock);
1945                 if (cmd->se_lun->lun_sep) {
1946                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1947                                         cmd->data_length;
1948                 }
1949                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1950
1951                 trace_target_cmd_complete(cmd);
1952                 ret = cmd->se_tfo->queue_data_in(cmd);
1953                 if (ret == -EAGAIN || ret == -ENOMEM)
1954                         goto queue_full;
1955                 break;
1956         case DMA_TO_DEVICE:
1957                 spin_lock(&cmd->se_lun->lun_sep_lock);
1958                 if (cmd->se_lun->lun_sep) {
1959                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
1960                                 cmd->data_length;
1961                 }
1962                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1963                 /*
1964                  * Check if we need to send READ payload for BIDI-COMMAND
1965                  */
1966                 if (cmd->se_cmd_flags & SCF_BIDI) {
1967                         spin_lock(&cmd->se_lun->lun_sep_lock);
1968                         if (cmd->se_lun->lun_sep) {
1969                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1970                                         cmd->data_length;
1971                         }
1972                         spin_unlock(&cmd->se_lun->lun_sep_lock);
1973                         ret = cmd->se_tfo->queue_data_in(cmd);
1974                         if (ret == -EAGAIN || ret == -ENOMEM)
1975                                 goto queue_full;
1976                         break;
1977                 }
1978                 /* Fall through for DMA_TO_DEVICE */
1979         case DMA_NONE:
1980                 trace_target_cmd_complete(cmd);
1981                 ret = cmd->se_tfo->queue_status(cmd);
1982                 if (ret == -EAGAIN || ret == -ENOMEM)
1983                         goto queue_full;
1984                 break;
1985         default:
1986                 break;
1987         }
1988
1989         transport_lun_remove_cmd(cmd);
1990         transport_cmd_check_stop_to_fabric(cmd);
1991         return;
1992
1993 queue_full:
1994         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
1995                 " data_direction: %d\n", cmd, cmd->data_direction);
1996         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1997         transport_handle_queue_full(cmd, cmd->se_dev);
1998 }
1999
2000 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2001 {
2002         struct scatterlist *sg;
2003         int count;
2004
2005         for_each_sg(sgl, sg, nents, count)
2006                 __free_page(sg_page(sg));
2007
2008         kfree(sgl);
2009 }
2010
2011 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2012 {
2013         /*
2014          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2015          * emulation, and free + reset pointers if necessary..
2016          */
2017         if (!cmd->t_data_sg_orig)
2018                 return;
2019
2020         kfree(cmd->t_data_sg);
2021         cmd->t_data_sg = cmd->t_data_sg_orig;
2022         cmd->t_data_sg_orig = NULL;
2023         cmd->t_data_nents = cmd->t_data_nents_orig;
2024         cmd->t_data_nents_orig = 0;
2025 }
2026
2027 static inline void transport_free_pages(struct se_cmd *cmd)
2028 {
2029         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2030                 transport_reset_sgl_orig(cmd);
2031                 return;
2032         }
2033         transport_reset_sgl_orig(cmd);
2034
2035         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2036         cmd->t_data_sg = NULL;
2037         cmd->t_data_nents = 0;
2038
2039         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2040         cmd->t_bidi_data_sg = NULL;
2041         cmd->t_bidi_data_nents = 0;
2042 }
2043
2044 /**
2045  * transport_release_cmd - free a command
2046  * @cmd:       command to free
2047  *
2048  * This routine unconditionally frees a command, and reference counting
2049  * or list removal must be done in the caller.
2050  */
2051 static int transport_release_cmd(struct se_cmd *cmd)
2052 {
2053         BUG_ON(!cmd->se_tfo);
2054
2055         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2056                 core_tmr_release_req(cmd->se_tmr_req);
2057         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2058                 kfree(cmd->t_task_cdb);
2059         /*
2060          * If this cmd has been setup with target_get_sess_cmd(), drop
2061          * the kref and call ->release_cmd() in kref callback.
2062          */
2063         return target_put_sess_cmd(cmd->se_sess, cmd);
2064 }
2065
2066 /**
2067  * transport_put_cmd - release a reference to a command
2068  * @cmd:       command to release
2069  *
2070  * This routine releases our reference to the command and frees it if possible.
2071  */
2072 static int transport_put_cmd(struct se_cmd *cmd)
2073 {
2074         transport_free_pages(cmd);
2075         return transport_release_cmd(cmd);
2076 }
2077
2078 void *transport_kmap_data_sg(struct se_cmd *cmd)
2079 {
2080         struct scatterlist *sg = cmd->t_data_sg;
2081         struct page **pages;
2082         int i;
2083
2084         /*
2085          * We need to take into account a possible offset here for fabrics like
2086          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2087          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2088          */
2089         if (!cmd->t_data_nents)
2090                 return NULL;
2091
2092         BUG_ON(!sg);
2093         if (cmd->t_data_nents == 1)
2094                 return kmap(sg_page(sg)) + sg->offset;
2095
2096         /* >1 page. use vmap */
2097         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2098         if (!pages)
2099                 return NULL;
2100
2101         /* convert sg[] to pages[] */
2102         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2103                 pages[i] = sg_page(sg);
2104         }
2105
2106         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2107         kfree(pages);
2108         if (!cmd->t_data_vmap)
2109                 return NULL;
2110
2111         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2112 }
2113 EXPORT_SYMBOL(transport_kmap_data_sg);
2114
2115 void transport_kunmap_data_sg(struct se_cmd *cmd)
2116 {
2117         if (!cmd->t_data_nents) {
2118                 return;
2119         } else if (cmd->t_data_nents == 1) {
2120                 kunmap(sg_page(cmd->t_data_sg));
2121                 return;
2122         }
2123
2124         vunmap(cmd->t_data_vmap);
2125         cmd->t_data_vmap = NULL;
2126 }
2127 EXPORT_SYMBOL(transport_kunmap_data_sg);
2128
2129 int
2130 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2131                  bool zero_page)
2132 {
2133         struct scatterlist *sg;
2134         struct page *page;
2135         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2136         unsigned int nent;
2137         int i = 0;
2138
2139         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2140         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2141         if (!sg)
2142                 return -ENOMEM;
2143
2144         sg_init_table(sg, nent);
2145
2146         while (length) {
2147                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2148                 page = alloc_page(GFP_KERNEL | zero_flag);
2149                 if (!page)
2150                         goto out;
2151
2152                 sg_set_page(&sg[i], page, page_len, 0);
2153                 length -= page_len;
2154                 i++;
2155         }
2156         *sgl = sg;
2157         *nents = nent;
2158         return 0;
2159
2160 out:
2161         while (i > 0) {
2162                 i--;
2163                 __free_page(sg_page(&sg[i]));
2164         }
2165         kfree(sg);
2166         return -ENOMEM;
2167 }
2168
2169 /*
2170  * Allocate any required resources to execute the command.  For writes we
2171  * might not have the payload yet, so notify the fabric via a call to
2172  * ->write_pending instead. Otherwise place it on the execution queue.
2173  */
2174 sense_reason_t
2175 transport_generic_new_cmd(struct se_cmd *cmd)
2176 {
2177         int ret = 0;
2178
2179         /*
2180          * Determine is the TCM fabric module has already allocated physical
2181          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2182          * beforehand.
2183          */
2184         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2185             cmd->data_length) {
2186                 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2187
2188                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2189                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2190                         u32 bidi_length;
2191
2192                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2193                                 bidi_length = cmd->t_task_nolb *
2194                                               cmd->se_dev->dev_attrib.block_size;
2195                         else
2196                                 bidi_length = cmd->data_length;
2197
2198                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2199                                                &cmd->t_bidi_data_nents,
2200                                                bidi_length, zero_flag);
2201                         if (ret < 0)
2202                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2203                 }
2204
2205                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2206                                        cmd->data_length, zero_flag);
2207                 if (ret < 0)
2208                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2209         }
2210         /*
2211          * If this command is not a write we can execute it right here,
2212          * for write buffers we need to notify the fabric driver first
2213          * and let it call back once the write buffers are ready.
2214          */
2215         target_add_to_state_list(cmd);
2216         if (cmd->data_direction != DMA_TO_DEVICE) {
2217                 target_execute_cmd(cmd);
2218                 return 0;
2219         }
2220         transport_cmd_check_stop(cmd, false, true);
2221
2222         ret = cmd->se_tfo->write_pending(cmd);
2223         if (ret == -EAGAIN || ret == -ENOMEM)
2224                 goto queue_full;
2225
2226         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2227         WARN_ON(ret);
2228
2229         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2230
2231 queue_full:
2232         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2233         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2234         transport_handle_queue_full(cmd, cmd->se_dev);
2235         return 0;
2236 }
2237 EXPORT_SYMBOL(transport_generic_new_cmd);
2238
2239 static void transport_write_pending_qf(struct se_cmd *cmd)
2240 {
2241         int ret;
2242
2243         ret = cmd->se_tfo->write_pending(cmd);
2244         if (ret == -EAGAIN || ret == -ENOMEM) {
2245                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2246                          cmd);
2247                 transport_handle_queue_full(cmd, cmd->se_dev);
2248         }
2249 }
2250
2251 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2252 {
2253         unsigned long flags;
2254         int ret = 0;
2255
2256         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2257                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2258                          transport_wait_for_tasks(cmd);
2259
2260                 ret = transport_release_cmd(cmd);
2261         } else {
2262                 if (wait_for_tasks)
2263                         transport_wait_for_tasks(cmd);
2264                 /*
2265                  * Handle WRITE failure case where transport_generic_new_cmd()
2266                  * has already added se_cmd to state_list, but fabric has
2267                  * failed command before I/O submission.
2268                  */
2269                 if (cmd->state_active) {
2270                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2271                         target_remove_from_state_list(cmd);
2272                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2273                 }
2274
2275                 if (cmd->se_lun)
2276                         transport_lun_remove_cmd(cmd);
2277
2278                 ret = transport_put_cmd(cmd);
2279         }
2280         return ret;
2281 }
2282 EXPORT_SYMBOL(transport_generic_free_cmd);
2283
2284 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2285  * @se_sess:    session to reference
2286  * @se_cmd:     command descriptor to add
2287  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2288  */
2289 int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2290                                bool ack_kref)
2291 {
2292         unsigned long flags;
2293         int ret = 0;
2294
2295         kref_init(&se_cmd->cmd_kref);
2296         /*
2297          * Add a second kref if the fabric caller is expecting to handle
2298          * fabric acknowledgement that requires two target_put_sess_cmd()
2299          * invocations before se_cmd descriptor release.
2300          */
2301         if (ack_kref == true) {
2302                 kref_get(&se_cmd->cmd_kref);
2303                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2304         }
2305
2306         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2307         if (se_sess->sess_tearing_down) {
2308                 ret = -ESHUTDOWN;
2309                 goto out;
2310         }
2311         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2312 out:
2313         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2314         return ret;
2315 }
2316 EXPORT_SYMBOL(target_get_sess_cmd);
2317
2318 static void target_release_cmd_kref(struct kref *kref)
2319 {
2320         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2321         struct se_session *se_sess = se_cmd->se_sess;
2322
2323         if (list_empty(&se_cmd->se_cmd_list)) {
2324                 spin_unlock(&se_sess->sess_cmd_lock);
2325                 se_cmd->se_tfo->release_cmd(se_cmd);
2326                 return;
2327         }
2328         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2329                 spin_unlock(&se_sess->sess_cmd_lock);
2330                 complete(&se_cmd->cmd_wait_comp);
2331                 return;
2332         }
2333         list_del(&se_cmd->se_cmd_list);
2334         spin_unlock(&se_sess->sess_cmd_lock);
2335
2336         se_cmd->se_tfo->release_cmd(se_cmd);
2337 }
2338
2339 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2340  * @se_sess:    session to reference
2341  * @se_cmd:     command descriptor to drop
2342  */
2343 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2344 {
2345         return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2346                         &se_sess->sess_cmd_lock);
2347 }
2348 EXPORT_SYMBOL(target_put_sess_cmd);
2349
2350 /* target_sess_cmd_list_set_waiting - Flag all commands in
2351  *         sess_cmd_list to complete cmd_wait_comp.  Set
2352  *         sess_tearing_down so no more commands are queued.
2353  * @se_sess:    session to flag
2354  */
2355 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2356 {
2357         struct se_cmd *se_cmd;
2358         unsigned long flags;
2359
2360         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2361         if (se_sess->sess_tearing_down) {
2362                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2363                 return;
2364         }
2365         se_sess->sess_tearing_down = 1;
2366         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2367
2368         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2369                 se_cmd->cmd_wait_set = 1;
2370
2371         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2372 }
2373 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2374
2375 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2376  * @se_sess:    session to wait for active I/O
2377  */
2378 void target_wait_for_sess_cmds(struct se_session *se_sess)
2379 {
2380         struct se_cmd *se_cmd, *tmp_cmd;
2381         unsigned long flags;
2382
2383         list_for_each_entry_safe(se_cmd, tmp_cmd,
2384                                 &se_sess->sess_wait_list, se_cmd_list) {
2385                 list_del(&se_cmd->se_cmd_list);
2386
2387                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2388                         " %d\n", se_cmd, se_cmd->t_state,
2389                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2390
2391                 wait_for_completion(&se_cmd->cmd_wait_comp);
2392                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2393                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2394                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2395
2396                 se_cmd->se_tfo->release_cmd(se_cmd);
2397         }
2398
2399         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2400         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2401         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2402
2403 }
2404 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2405
2406 static int transport_clear_lun_ref_thread(void *p)
2407 {
2408         struct se_lun *lun = p;
2409
2410         percpu_ref_kill(&lun->lun_ref);
2411
2412         wait_for_completion(&lun->lun_ref_comp);
2413         complete(&lun->lun_shutdown_comp);
2414
2415         return 0;
2416 }
2417
2418 int transport_clear_lun_ref(struct se_lun *lun)
2419 {
2420         struct task_struct *kt;
2421
2422         kt = kthread_run(transport_clear_lun_ref_thread, lun,
2423                         "tcm_cl_%u", lun->unpacked_lun);
2424         if (IS_ERR(kt)) {
2425                 pr_err("Unable to start clear_lun thread\n");
2426                 return PTR_ERR(kt);
2427         }
2428         wait_for_completion(&lun->lun_shutdown_comp);
2429
2430         return 0;
2431 }
2432
2433 /**
2434  * transport_wait_for_tasks - wait for completion to occur
2435  * @cmd:        command to wait
2436  *
2437  * Called from frontend fabric context to wait for storage engine
2438  * to pause and/or release frontend generated struct se_cmd.
2439  */
2440 bool transport_wait_for_tasks(struct se_cmd *cmd)
2441 {
2442         unsigned long flags;
2443
2444         spin_lock_irqsave(&cmd->t_state_lock, flags);
2445         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2446             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2447                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2448                 return false;
2449         }
2450
2451         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2452             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2453                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2454                 return false;
2455         }
2456
2457         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2458                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2459                 return false;
2460         }
2461
2462         cmd->transport_state |= CMD_T_STOP;
2463
2464         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2465                 " i_state: %d, t_state: %d, CMD_T_STOP\n",
2466                 cmd, cmd->se_tfo->get_task_tag(cmd),
2467                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2468
2469         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2470
2471         wait_for_completion(&cmd->t_transport_stop_comp);
2472
2473         spin_lock_irqsave(&cmd->t_state_lock, flags);
2474         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2475
2476         pr_debug("wait_for_tasks: Stopped wait_for_completion("
2477                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2478                 cmd->se_tfo->get_task_tag(cmd));
2479
2480         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2481
2482         return true;
2483 }
2484 EXPORT_SYMBOL(transport_wait_for_tasks);
2485
2486 static int transport_get_sense_codes(
2487         struct se_cmd *cmd,
2488         u8 *asc,
2489         u8 *ascq)
2490 {
2491         *asc = cmd->scsi_asc;
2492         *ascq = cmd->scsi_ascq;
2493
2494         return 0;
2495 }
2496
2497 static
2498 void transport_err_sector_info(unsigned char *buffer, sector_t bad_sector)
2499 {
2500         /* Place failed LBA in sense data information descriptor 0. */
2501         buffer[SPC_ADD_SENSE_LEN_OFFSET] = 0xc;
2502         buffer[SPC_DESC_TYPE_OFFSET] = 0; /* Information */
2503         buffer[SPC_ADDITIONAL_DESC_LEN_OFFSET] = 0xa;
2504         buffer[SPC_VALIDITY_OFFSET] = 0x80;
2505
2506         /* Descriptor Information: failing sector */
2507         put_unaligned_be64(bad_sector, &buffer[12]);
2508 }
2509
2510 int
2511 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2512                 sense_reason_t reason, int from_transport)
2513 {
2514         unsigned char *buffer = cmd->sense_buffer;
2515         unsigned long flags;
2516         u8 asc = 0, ascq = 0;
2517
2518         spin_lock_irqsave(&cmd->t_state_lock, flags);
2519         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2520                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2521                 return 0;
2522         }
2523         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2524         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2525
2526         if (!reason && from_transport)
2527                 goto after_reason;
2528
2529         if (!from_transport)
2530                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2531
2532         /*
2533          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2534          * SENSE KEY values from include/scsi/scsi.h
2535          */
2536         switch (reason) {
2537         case TCM_NO_SENSE:
2538                 /* CURRENT ERROR */
2539                 buffer[0] = 0x70;
2540                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2541                 /* Not Ready */
2542                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2543                 /* NO ADDITIONAL SENSE INFORMATION */
2544                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2545                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2546                 break;
2547         case TCM_NON_EXISTENT_LUN:
2548                 /* CURRENT ERROR */
2549                 buffer[0] = 0x70;
2550                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2551                 /* ILLEGAL REQUEST */
2552                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2553                 /* LOGICAL UNIT NOT SUPPORTED */
2554                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2555                 break;
2556         case TCM_UNSUPPORTED_SCSI_OPCODE:
2557         case TCM_SECTOR_COUNT_TOO_MANY:
2558                 /* CURRENT ERROR */
2559                 buffer[0] = 0x70;
2560                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2561                 /* ILLEGAL REQUEST */
2562                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2563                 /* INVALID COMMAND OPERATION CODE */
2564                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2565                 break;
2566         case TCM_UNKNOWN_MODE_PAGE:
2567                 /* CURRENT ERROR */
2568                 buffer[0] = 0x70;
2569                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2570                 /* ILLEGAL REQUEST */
2571                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2572                 /* INVALID FIELD IN CDB */
2573                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2574                 break;
2575         case TCM_CHECK_CONDITION_ABORT_CMD:
2576                 /* CURRENT ERROR */
2577                 buffer[0] = 0x70;
2578                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2579                 /* ABORTED COMMAND */
2580                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2581                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2582                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2583                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2584                 break;
2585         case TCM_INCORRECT_AMOUNT_OF_DATA:
2586                 /* CURRENT ERROR */
2587                 buffer[0] = 0x70;
2588                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2589                 /* ABORTED COMMAND */
2590                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2591                 /* WRITE ERROR */
2592                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2593                 /* NOT ENOUGH UNSOLICITED DATA */
2594                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2595                 break;
2596         case TCM_INVALID_CDB_FIELD:
2597                 /* CURRENT ERROR */
2598                 buffer[0] = 0x70;
2599                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2600                 /* ILLEGAL REQUEST */
2601                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2602                 /* INVALID FIELD IN CDB */
2603                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2604                 break;
2605         case TCM_INVALID_PARAMETER_LIST:
2606                 /* CURRENT ERROR */
2607                 buffer[0] = 0x70;
2608                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2609                 /* ILLEGAL REQUEST */
2610                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2611                 /* INVALID FIELD IN PARAMETER LIST */
2612                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2613                 break;
2614         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2615                 /* CURRENT ERROR */
2616                 buffer[0] = 0x70;
2617                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2618                 /* ILLEGAL REQUEST */
2619                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2620                 /* PARAMETER LIST LENGTH ERROR */
2621                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2622                 break;
2623         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2624                 /* CURRENT ERROR */
2625                 buffer[0] = 0x70;
2626                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2627                 /* ABORTED COMMAND */
2628                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2629                 /* WRITE ERROR */
2630                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2631                 /* UNEXPECTED_UNSOLICITED_DATA */
2632                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2633                 break;
2634         case TCM_SERVICE_CRC_ERROR:
2635                 /* CURRENT ERROR */
2636                 buffer[0] = 0x70;
2637                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2638                 /* ABORTED COMMAND */
2639                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2640                 /* PROTOCOL SERVICE CRC ERROR */
2641                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2642                 /* N/A */
2643                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2644                 break;
2645         case TCM_SNACK_REJECTED:
2646                 /* CURRENT ERROR */
2647                 buffer[0] = 0x70;
2648                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2649                 /* ABORTED COMMAND */
2650                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2651                 /* READ ERROR */
2652                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2653                 /* FAILED RETRANSMISSION REQUEST */
2654                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2655                 break;
2656         case TCM_WRITE_PROTECTED:
2657                 /* CURRENT ERROR */
2658                 buffer[0] = 0x70;
2659                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2660                 /* DATA PROTECT */
2661                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2662                 /* WRITE PROTECTED */
2663                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2664                 break;
2665         case TCM_ADDRESS_OUT_OF_RANGE:
2666                 /* CURRENT ERROR */
2667                 buffer[0] = 0x70;
2668                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2669                 /* ILLEGAL REQUEST */
2670                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2671                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2672                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2673                 break;
2674         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2675                 /* CURRENT ERROR */
2676                 buffer[0] = 0x70;
2677                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2678                 /* UNIT ATTENTION */
2679                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2680                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2681                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2682                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2683                 break;
2684         case TCM_CHECK_CONDITION_NOT_READY:
2685                 /* CURRENT ERROR */
2686                 buffer[0] = 0x70;
2687                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2688                 /* Not Ready */
2689                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2690                 transport_get_sense_codes(cmd, &asc, &ascq);
2691                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2692                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2693                 break;
2694         case TCM_MISCOMPARE_VERIFY:
2695                 /* CURRENT ERROR */
2696                 buffer[0] = 0x70;
2697                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2698                 buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
2699                 /* MISCOMPARE DURING VERIFY OPERATION */
2700                 buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
2701                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
2702                 break;
2703         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
2704                 /* CURRENT ERROR */
2705                 buffer[0] = 0x70;
2706                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2707                 /* ILLEGAL REQUEST */
2708                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2709                 /* LOGICAL BLOCK GUARD CHECK FAILED */
2710                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2711                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x01;
2712                 transport_err_sector_info(buffer, cmd->bad_sector);
2713                 break;
2714         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
2715                 /* CURRENT ERROR */
2716                 buffer[0] = 0x70;
2717                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2718                 /* ILLEGAL REQUEST */
2719                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2720                 /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2721                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2722                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x02;
2723                 transport_err_sector_info(buffer, cmd->bad_sector);
2724                 break;
2725         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
2726                 /* CURRENT ERROR */
2727                 buffer[0] = 0x70;
2728                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2729                 /* ILLEGAL REQUEST */
2730                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2731                 /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2732                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2733                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2734                 transport_err_sector_info(buffer, cmd->bad_sector);
2735                 break;
2736         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2737         default:
2738                 /* CURRENT ERROR */
2739                 buffer[0] = 0x70;
2740                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2741                 /*
2742                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2743                  * Solaris initiators.  Returning NOT READY instead means the
2744                  * operations will be retried a finite number of times and we
2745                  * can survive intermittent errors.
2746                  */
2747                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2748                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2749                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2750                 break;
2751         }
2752         /*
2753          * This code uses linux/include/scsi/scsi.h SAM status codes!
2754          */
2755         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2756         /*
2757          * Automatically padded, this value is encoded in the fabric's
2758          * data_length response PDU containing the SCSI defined sense data.
2759          */
2760         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2761
2762 after_reason:
2763         trace_target_cmd_complete(cmd);
2764         return cmd->se_tfo->queue_status(cmd);
2765 }
2766 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2767
2768 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2769 {
2770         if (!(cmd->transport_state & CMD_T_ABORTED))
2771                 return 0;
2772
2773         if (!send_status || (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
2774                 return 1;
2775
2776         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2777                  cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2778
2779         cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
2780         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2781         trace_target_cmd_complete(cmd);
2782         cmd->se_tfo->queue_status(cmd);
2783
2784         return 1;
2785 }
2786 EXPORT_SYMBOL(transport_check_aborted_status);
2787
2788 void transport_send_task_abort(struct se_cmd *cmd)
2789 {
2790         unsigned long flags;
2791
2792         spin_lock_irqsave(&cmd->t_state_lock, flags);
2793         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION | SCF_SENT_DELAYED_TAS)) {
2794                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2795                 return;
2796         }
2797         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2798
2799         /*
2800          * If there are still expected incoming fabric WRITEs, we wait
2801          * until until they have completed before sending a TASK_ABORTED
2802          * response.  This response with TASK_ABORTED status will be
2803          * queued back to fabric module by transport_check_aborted_status().
2804          */
2805         if (cmd->data_direction == DMA_TO_DEVICE) {
2806                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2807                         cmd->transport_state |= CMD_T_ABORTED;
2808                         smp_mb__after_atomic_inc();
2809                         return;
2810                 }
2811         }
2812         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2813
2814         transport_lun_remove_cmd(cmd);
2815
2816         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2817                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
2818                 cmd->se_tfo->get_task_tag(cmd));
2819
2820         trace_target_cmd_complete(cmd);
2821         cmd->se_tfo->queue_status(cmd);
2822 }
2823
2824 static void target_tmr_work(struct work_struct *work)
2825 {
2826         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2827         struct se_device *dev = cmd->se_dev;
2828         struct se_tmr_req *tmr = cmd->se_tmr_req;
2829         int ret;
2830
2831         switch (tmr->function) {
2832         case TMR_ABORT_TASK:
2833                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2834                 break;
2835         case TMR_ABORT_TASK_SET:
2836         case TMR_CLEAR_ACA:
2837         case TMR_CLEAR_TASK_SET:
2838                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2839                 break;
2840         case TMR_LUN_RESET:
2841                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2842                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2843                                          TMR_FUNCTION_REJECTED;
2844                 break;
2845         case TMR_TARGET_WARM_RESET:
2846                 tmr->response = TMR_FUNCTION_REJECTED;
2847                 break;
2848         case TMR_TARGET_COLD_RESET:
2849                 tmr->response = TMR_FUNCTION_REJECTED;
2850                 break;
2851         default:
2852                 pr_err("Uknown TMR function: 0x%02x.\n",
2853                                 tmr->function);
2854                 tmr->response = TMR_FUNCTION_REJECTED;
2855                 break;
2856         }
2857
2858         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2859         cmd->se_tfo->queue_tm_rsp(cmd);
2860
2861         transport_cmd_check_stop_to_fabric(cmd);
2862 }
2863
2864 int transport_generic_handle_tmr(
2865         struct se_cmd *cmd)
2866 {
2867         INIT_WORK(&cmd->work, target_tmr_work);
2868         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2869         return 0;
2870 }
2871 EXPORT_SYMBOL(transport_generic_handle_tmr);