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/blkdev.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/kthread.h>
  34 #include <linux/in.h>
  35 #include <linux/cdrom.h>
  36 #include <linux/module.h>
  37 #include <linux/ratelimit.h>
  38 #include <asm/unaligned.h>
  39 #include <net/sock.h>
  40 #include <net/tcp.h>
  41 #include <scsi/scsi.h>
  42 #include <scsi/scsi_cmnd.h>
  43 #include <scsi/scsi_tcq.h>
  44
  45 #include <target/target_core_base.h>
  46 #include <target/target_core_backend.h>
  47 #include <target/target_core_fabric.h>
  48 #include <target/target_core_configfs.h>
  49
  50 #include "target_core_internal.h"
  51 #include "target_core_alua.h"
  52 #include "target_core_pr.h"
  53 #include "target_core_ua.h"
  54
  55 #define CREATE_TRACE_POINTS
  56 #include <trace/events/target.h>
  57
  58 static struct workqueue_struct *target_completion_wq;
  59 static struct kmem_cache *se_sess_cache;
  60 struct kmem_cache *se_ua_cache;
  61 struct kmem_cache *t10_pr_reg_cache;
  62 struct kmem_cache *t10_alua_lu_gp_cache;
  63 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  64 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  65 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
  66
  67 static void transport_complete_task_attr(struct se_cmd *cmd);
  68 static void transport_handle_queue_full(struct se_cmd *cmd,
  69                 struct se_device *dev);
  70 static int transport_put_cmd(struct se_cmd *cmd);
  71 static void target_complete_ok_work(struct work_struct *work);
  72
  73 int init_se_kmem_caches(void)
  74 {
  75         se_sess_cache = kmem_cache_create("se_sess_cache",
  76                         sizeof(struct se_session), __alignof__(struct se_session),
  77                         0, NULL);
  78         if (!se_sess_cache) {
  79                 pr_err("kmem_cache_create() for struct se_session"
  80                                 " failed\n");
  81                 goto out;
  82         }
  83         se_ua_cache = kmem_cache_create("se_ua_cache",
  84                         sizeof(struct se_ua), __alignof__(struct se_ua),
  85                         0, NULL);
  86         if (!se_ua_cache) {
  87                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  88                 goto out_free_sess_cache;
  89         }
  90         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  91                         sizeof(struct t10_pr_registration),
  92                         __alignof__(struct t10_pr_registration), 0, NULL);
  93         if (!t10_pr_reg_cache) {
  94                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  95                                 " failed\n");
  96                 goto out_free_ua_cache;
  97         }
  98         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
  99                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
 100                         0, NULL);
 101         if (!t10_alua_lu_gp_cache) {
 102                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 103                                 " failed\n");
 104                 goto out_free_pr_reg_cache;
 105         }
 106         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 107                         sizeof(struct t10_alua_lu_gp_member),
 108                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 109         if (!t10_alua_lu_gp_mem_cache) {
 110                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 111                                 "cache failed\n");
 112                 goto out_free_lu_gp_cache;
 113         }
 114         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 115                         sizeof(struct t10_alua_tg_pt_gp),
 116                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 117         if (!t10_alua_tg_pt_gp_cache) {
 118                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 119                                 "cache failed\n");
 120                 goto out_free_lu_gp_mem_cache;
 121         }
 122         t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
 123                         "t10_alua_tg_pt_gp_mem_cache",
 124                         sizeof(struct t10_alua_tg_pt_gp_member),
 125                         __alignof__(struct t10_alua_tg_pt_gp_member),
 126                         0, NULL);
 127         if (!t10_alua_tg_pt_gp_mem_cache) {
 128                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 129                                 "mem_t failed\n");
 130                 goto out_free_tg_pt_gp_cache;
 131         }
 132
 133         target_completion_wq = alloc_workqueue("target_completion",
 134                                                WQ_MEM_RECLAIM, 0);
 135         if (!target_completion_wq)
 136                 goto out_free_tg_pt_gp_mem_cache;
 137
 138         return 0;
 139
 140 out_free_tg_pt_gp_mem_cache:
 141         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 142 out_free_tg_pt_gp_cache:
 143         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 144 out_free_lu_gp_mem_cache:
 145         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 146 out_free_lu_gp_cache:
 147         kmem_cache_destroy(t10_alua_lu_gp_cache);
 148 out_free_pr_reg_cache:
 149         kmem_cache_destroy(t10_pr_reg_cache);
 150 out_free_ua_cache:
 151         kmem_cache_destroy(se_ua_cache);
 152 out_free_sess_cache:
 153         kmem_cache_destroy(se_sess_cache);
 154 out:
 155         return -ENOMEM;
 156 }
 157
 158 void release_se_kmem_caches(void)
 159 {
 160         destroy_workqueue(target_completion_wq);
 161         kmem_cache_destroy(se_sess_cache);
 162         kmem_cache_destroy(se_ua_cache);
 163         kmem_cache_destroy(t10_pr_reg_cache);
 164         kmem_cache_destroy(t10_alua_lu_gp_cache);
 165         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 166         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 167         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 168 }
 169
 170 /* This code ensures unique mib indexes are handed out. */
 171 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 172 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 173
 174 /*
 175  * Allocate a new row index for the entry type specified
 176  */
 177 u32 scsi_get_new_index(scsi_index_t type)
 178 {
 179         u32 new_index;
 180
 181         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 182
 183         spin_lock(&scsi_mib_index_lock);
 184         new_index = ++scsi_mib_index[type];
 185         spin_unlock(&scsi_mib_index_lock);
 186
 187         return new_index;
 188 }
 189
 190 void transport_subsystem_check_init(void)
 191 {
 192         int ret;
 193         static int sub_api_initialized;
 194
 195         if (sub_api_initialized)
 196                 return;
 197
 198         ret = request_module("target_core_iblock");
 199         if (ret != 0)
 200                 pr_err("Unable to load target_core_iblock\n");
 201
 202         ret = request_module("target_core_file");
 203         if (ret != 0)
 204                 pr_err("Unable to load target_core_file\n");
 205
 206         ret = request_module("target_core_pscsi");
 207         if (ret != 0)
 208                 pr_err("Unable to load target_core_pscsi\n");
 209
 210         sub_api_initialized = 1;
 211 }
 212
 213 struct se_session *transport_init_session(void)
 214 {
 215         struct se_session *se_sess;
 216
 217         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 218         if (!se_sess) {
 219                 pr_err("Unable to allocate struct se_session from"
 220                                 " se_sess_cache\n");
 221                 return ERR_PTR(-ENOMEM);
 222         }
 223         INIT_LIST_HEAD(&se_sess->sess_list);
 224         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 225         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 226         INIT_LIST_HEAD(&se_sess->sess_wait_list);
 227         spin_lock_init(&se_sess->sess_cmd_lock);
 228         kref_init(&se_sess->sess_kref);
 229
 230         return se_sess;
 231 }
 232 EXPORT_SYMBOL(transport_init_session);
 233
 234 int transport_alloc_session_tags(struct se_session *se_sess,
 235                                  unsigned int tag_num, unsigned int tag_size)
 236 {
 237         int rc;
 238
 239         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size, GFP_KERNEL);
 240         if (!se_sess->sess_cmd_map) {
 241                 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 242                 return -ENOMEM;
 243         }
 244
 245         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
 246         if (rc < 0) {
 247                 pr_err("Unable to init se_sess->sess_tag_pool,"
 248                         " tag_num: %u\n", tag_num);
 249                 kfree(se_sess->sess_cmd_map);
 250                 se_sess->sess_cmd_map = NULL;
 251                 return -ENOMEM;
 252         }
 253
 254         return 0;
 255 }
 256 EXPORT_SYMBOL(transport_alloc_session_tags);
 257
 258 struct se_session *transport_init_session_tags(unsigned int tag_num,
 259                                                unsigned int tag_size)
 260 {
 261         struct se_session *se_sess;
 262         int rc;
 263
 264         se_sess = transport_init_session();
 265         if (IS_ERR(se_sess))
 266                 return se_sess;
 267
 268         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 269         if (rc < 0) {
 270                 transport_free_session(se_sess);
 271                 return ERR_PTR(-ENOMEM);
 272         }
 273
 274         return se_sess;
 275 }
 276 EXPORT_SYMBOL(transport_init_session_tags);
 277
 278 /*
 279  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 280  */
 281 void __transport_register_session(
 282         struct se_portal_group *se_tpg,
 283         struct se_node_acl *se_nacl,
 284         struct se_session *se_sess,
 285         void *fabric_sess_ptr)
 286 {
 287         unsigned char buf[PR_REG_ISID_LEN];
 288
 289         se_sess->se_tpg = se_tpg;
 290         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 291         /*
 292          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 293          *
 294          * Only set for struct se_session's that will actually be moving I/O.
 295          * eg: *NOT* discovery sessions.
 296          */
 297         if (se_nacl) {
 298                 /*
 299                  * If the fabric module supports an ISID based TransportID,
 300                  * save this value in binary from the fabric I_T Nexus now.
 301                  */
 302                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 303                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 304                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 305                                         &buf[0], PR_REG_ISID_LEN);
 306                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 307                 }
 308                 kref_get(&se_nacl->acl_kref);
 309
 310                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 311                 /*
 312                  * The se_nacl->nacl_sess pointer will be set to the
 313                  * last active I_T Nexus for each struct se_node_acl.
 314                  */
 315                 se_nacl->nacl_sess = se_sess;
 316
 317                 list_add_tail(&se_sess->sess_acl_list,
 318                               &se_nacl->acl_sess_list);
 319                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 320         }
 321         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 322
 323         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 324                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 325 }
 326 EXPORT_SYMBOL(__transport_register_session);
 327
 328 void transport_register_session(
 329         struct se_portal_group *se_tpg,
 330         struct se_node_acl *se_nacl,
 331         struct se_session *se_sess,
 332         void *fabric_sess_ptr)
 333 {
 334         unsigned long flags;
 335
 336         spin_lock_irqsave(&se_tpg->session_lock, flags);
 337         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 338         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 339 }
 340 EXPORT_SYMBOL(transport_register_session);
 341
 342 static void target_release_session(struct kref *kref)
 343 {
 344         struct se_session *se_sess = container_of(kref,
 345                         struct se_session, sess_kref);
 346         struct se_portal_group *se_tpg = se_sess->se_tpg;
 347
 348         se_tpg->se_tpg_tfo->close_session(se_sess);
 349 }
 350
 351 void target_get_session(struct se_session *se_sess)
 352 {
 353         kref_get(&se_sess->sess_kref);
 354 }
 355 EXPORT_SYMBOL(target_get_session);
 356
 357 void target_put_session(struct se_session *se_sess)
 358 {
 359         struct se_portal_group *tpg = se_sess->se_tpg;
 360
 361         if (tpg->se_tpg_tfo->put_session != NULL) {
 362                 tpg->se_tpg_tfo->put_session(se_sess);
 363                 return;
 364         }
 365         kref_put(&se_sess->sess_kref, target_release_session);
 366 }
 367 EXPORT_SYMBOL(target_put_session);
 368
 369 static void target_complete_nacl(struct kref *kref)
 370 {
 371         struct se_node_acl *nacl = container_of(kref,
 372                                 struct se_node_acl, acl_kref);
 373
 374         complete(&nacl->acl_free_comp);
 375 }
 376
 377 void target_put_nacl(struct se_node_acl *nacl)
 378 {
 379         kref_put(&nacl->acl_kref, target_complete_nacl);
 380 }
 381
 382 void transport_deregister_session_configfs(struct se_session *se_sess)
 383 {
 384         struct se_node_acl *se_nacl;
 385         unsigned long flags;
 386         /*
 387          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 388          */
 389         se_nacl = se_sess->se_node_acl;
 390         if (se_nacl) {
 391                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 392                 if (se_nacl->acl_stop == 0)
 393                         list_del(&se_sess->sess_acl_list);
 394                 /*
 395                  * If the session list is empty, then clear the pointer.
 396                  * Otherwise, set the struct se_session pointer from the tail
 397                  * element of the per struct se_node_acl active session list.
 398                  */
 399                 if (list_empty(&se_nacl->acl_sess_list))
 400                         se_nacl->nacl_sess = NULL;
 401                 else {
 402                         se_nacl->nacl_sess = container_of(
 403                                         se_nacl->acl_sess_list.prev,
 404                                         struct se_session, sess_acl_list);
 405                 }
 406                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 407         }
 408 }
 409 EXPORT_SYMBOL(transport_deregister_session_configfs);
 410
 411 void transport_free_session(struct se_session *se_sess)
 412 {
 413         if (se_sess->sess_cmd_map) {
 414                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 415                 kfree(se_sess->sess_cmd_map);
 416         }
 417         kmem_cache_free(se_sess_cache, se_sess);
 418 }
 419 EXPORT_SYMBOL(transport_free_session);
 420
 421 void transport_deregister_session(struct se_session *se_sess)
 422 {
 423         struct se_portal_group *se_tpg = se_sess->se_tpg;
 424         struct target_core_fabric_ops *se_tfo;
 425         struct se_node_acl *se_nacl;
 426         unsigned long flags;
 427         bool comp_nacl = true;
 428
 429         if (!se_tpg) {
 430                 transport_free_session(se_sess);
 431                 return;
 432         }
 433         se_tfo = se_tpg->se_tpg_tfo;
 434
 435         spin_lock_irqsave(&se_tpg->session_lock, flags);
 436         list_del(&se_sess->sess_list);
 437         se_sess->se_tpg = NULL;
 438         se_sess->fabric_sess_ptr = NULL;
 439         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 440
 441         /*
 442          * Determine if we need to do extra work for this initiator node's
 443          * struct se_node_acl if it had been previously dynamically generated.
 444          */
 445         se_nacl = se_sess->se_node_acl;
 446
 447         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 448         if (se_nacl && se_nacl->dynamic_node_acl) {
 449                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 450                         list_del(&se_nacl->acl_list);
 451                         se_tpg->num_node_acls--;
 452                         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 453                         core_tpg_wait_for_nacl_pr_ref(se_nacl);
 454                         core_free_device_list_for_node(se_nacl, se_tpg);
 455                         se_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
 456
 457                         comp_nacl = false;
 458                         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 459                 }
 460         }
 461         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 462
 463         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 464                 se_tpg->se_tpg_tfo->get_fabric_name());
 465         /*
 466          * If last kref is dropping now for an explict NodeACL, awake sleeping
 467          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 468          * removal context.
 469          */
 470         if (se_nacl && comp_nacl == true)
 471                 target_put_nacl(se_nacl);
 472
 473         transport_free_session(se_sess);
 474 }
 475 EXPORT_SYMBOL(transport_deregister_session);
 476
 477 /*
 478  * Called with cmd->t_state_lock held.
 479  */
 480 static void target_remove_from_state_list(struct se_cmd *cmd)
 481 {
 482         struct se_device *dev = cmd->se_dev;
 483         unsigned long flags;
 484
 485         if (!dev)
 486                 return;
 487
 488         if (cmd->transport_state & CMD_T_BUSY)
 489                 return;
 490
 491         spin_lock_irqsave(&dev->execute_task_lock, flags);
 492         if (cmd->state_active) {
 493                 list_del(&cmd->state_list);
 494                 cmd->state_active = false;
 495         }
 496         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 497 }
 498
 499 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 500                                     bool write_pending)
 501 {
 502         unsigned long flags;
 503
 504         spin_lock_irqsave(&cmd->t_state_lock, flags);
 505         if (write_pending)
 506                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 507
 508         /*
 509          * Determine if IOCTL context caller in requesting the stopping of this
 510          * command for LUN shutdown purposes.
 511          */
 512         if (cmd->transport_state & CMD_T_LUN_STOP) {
 513                 pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
 514                         __func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
 515
 516                 cmd->transport_state &= ~CMD_T_ACTIVE;
 517                 if (remove_from_lists)
 518                         target_remove_from_state_list(cmd);
 519                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 520
 521                 complete(&cmd->transport_lun_stop_comp);
 522                 return 1;
 523         }
 524
 525         if (remove_from_lists) {
 526                 target_remove_from_state_list(cmd);
 527
 528                 /*
 529                  * Clear struct se_cmd->se_lun before the handoff to FE.
 530                  */
 531                 cmd->se_lun = NULL;
 532         }
 533
 534         /*
 535          * Determine if frontend context caller is requesting the stopping of
 536          * this command for frontend exceptions.
 537          */
 538         if (cmd->transport_state & CMD_T_STOP) {
 539                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
 540                         __func__, __LINE__,
 541                         cmd->se_tfo->get_task_tag(cmd));
 542
 543                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 544
 545                 complete(&cmd->t_transport_stop_comp);
 546                 return 1;
 547         }
 548
 549         cmd->transport_state &= ~CMD_T_ACTIVE;
 550         if (remove_from_lists) {
 551                 /*
 552                  * Some fabric modules like tcm_loop can release
 553                  * their internally allocated I/O reference now and
 554                  * struct se_cmd now.
 555                  *
 556                  * Fabric modules are expected to return '1' here if the
 557                  * se_cmd being passed is released at this point,
 558                  * or zero if not being released.
 559                  */
 560                 if (cmd->se_tfo->check_stop_free != NULL) {
 561                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 562                         return cmd->se_tfo->check_stop_free(cmd);
 563                 }
 564         }
 565
 566         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 567         return 0;
 568 }
 569
 570 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 571 {
 572         return transport_cmd_check_stop(cmd, true, false);
 573 }
 574
 575 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 576 {
 577         struct se_lun *lun = cmd->se_lun;
 578         unsigned long flags;
 579
 580         if (!lun)
 581                 return;
 582
 583         spin_lock_irqsave(&lun->lun_cmd_lock, flags);
 584         if (!list_empty(&cmd->se_lun_node))
 585                 list_del_init(&cmd->se_lun_node);
 586         spin_unlock_irqrestore(&lun->lun_cmd_lock, flags);
 587 }
 588
 589 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 590 {
 591         if (transport_cmd_check_stop_to_fabric(cmd))
 592                 return;
 593         if (remove)
 594                 transport_put_cmd(cmd);
 595 }
 596
 597 static void target_complete_failure_work(struct work_struct *work)
 598 {
 599         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 600
 601         transport_generic_request_failure(cmd,
 602                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 603 }
 604
 605 /*
 606  * Used when asking transport to copy Sense Data from the underlying
 607  * Linux/SCSI struct scsi_cmnd
 608  */
 609 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 610 {
 611         struct se_device *dev = cmd->se_dev;
 612
 613         WARN_ON(!cmd->se_lun);
 614
 615         if (!dev)
 616                 return NULL;
 617
 618         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 619                 return NULL;
 620
 621         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 622
 623         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 624                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 625         return cmd->sense_buffer;
 626 }
 627
 628 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 629 {
 630         struct se_device *dev = cmd->se_dev;
 631         int success = scsi_status == GOOD;
 632         unsigned long flags;
 633
 634         cmd->scsi_status = scsi_status;
 635
 636
 637         spin_lock_irqsave(&cmd->t_state_lock, flags);
 638         cmd->transport_state &= ~CMD_T_BUSY;
 639
 640         if (dev && dev->transport->transport_complete) {
 641                 dev->transport->transport_complete(cmd,
 642                                 cmd->t_data_sg,
 643                                 transport_get_sense_buffer(cmd));
 644                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 645                         success = 1;
 646         }
 647
 648         /*
 649          * See if we are waiting to complete for an exception condition.
 650          */
 651         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
 652                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 653                 complete(&cmd->task_stop_comp);
 654                 return;
 655         }
 656
 657         if (!success)
 658                 cmd->transport_state |= CMD_T_FAILED;
 659
 660         /*
 661          * Check for case where an explict ABORT_TASK has been received
 662          * and transport_wait_for_tasks() will be waiting for completion..
 663          */
 664         if (cmd->transport_state & CMD_T_ABORTED &&
 665             cmd->transport_state & CMD_T_STOP) {
 666                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 667                 complete(&cmd->t_transport_stop_comp);
 668                 return;
 669         } else if (cmd->transport_state & CMD_T_FAILED) {
 670                 INIT_WORK(&cmd->work, target_complete_failure_work);
 671         } else {
 672                 INIT_WORK(&cmd->work, target_complete_ok_work);
 673         }
 674
 675         cmd->t_state = TRANSPORT_COMPLETE;
 676         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 677         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 678
 679         queue_work(target_completion_wq, &cmd->work);
 680 }
 681 EXPORT_SYMBOL(target_complete_cmd);
 682
 683 static void target_add_to_state_list(struct se_cmd *cmd)
 684 {
 685         struct se_device *dev = cmd->se_dev;
 686         unsigned long flags;
 687
 688         spin_lock_irqsave(&dev->execute_task_lock, flags);
 689         if (!cmd->state_active) {
 690                 list_add_tail(&cmd->state_list, &dev->state_list);
 691                 cmd->state_active = true;
 692         }
 693         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 694 }
 695
 696 /*
 697  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 698  */
 699 static void transport_write_pending_qf(struct se_cmd *cmd);
 700 static void transport_complete_qf(struct se_cmd *cmd);
 701
 702 void target_qf_do_work(struct work_struct *work)
 703 {
 704         struct se_device *dev = container_of(work, struct se_device,
 705                                         qf_work_queue);
 706         LIST_HEAD(qf_cmd_list);
 707         struct se_cmd *cmd, *cmd_tmp;
 708
 709         spin_lock_irq(&dev->qf_cmd_lock);
 710         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 711         spin_unlock_irq(&dev->qf_cmd_lock);
 712
 713         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 714                 list_del(&cmd->se_qf_node);
 715                 atomic_dec(&dev->dev_qf_count);
 716                 smp_mb__after_atomic_dec();
 717
 718                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 719                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 720                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 721                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 722                         : "UNKNOWN");
 723
 724                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 725                         transport_write_pending_qf(cmd);
 726                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 727                         transport_complete_qf(cmd);
 728         }
 729 }
 730
 731 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 732 {
 733         switch (cmd->data_direction) {
 734         case DMA_NONE:
 735                 return "NONE";
 736         case DMA_FROM_DEVICE:
 737                 return "READ";
 738         case DMA_TO_DEVICE:
 739                 return "WRITE";
 740         case DMA_BIDIRECTIONAL:
 741                 return "BIDI";
 742         default:
 743                 break;
 744         }
 745
 746         return "UNKNOWN";
 747 }
 748
 749 void transport_dump_dev_state(
 750         struct se_device *dev,
 751         char *b,
 752         int *bl)
 753 {
 754         *bl += sprintf(b + *bl, "Status: ");
 755         if (dev->export_count)
 756                 *bl += sprintf(b + *bl, "ACTIVATED");
 757         else
 758                 *bl += sprintf(b + *bl, "DEACTIVATED");
 759
 760         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 761         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 762                 dev->dev_attrib.block_size,
 763                 dev->dev_attrib.hw_max_sectors);
 764         *bl += sprintf(b + *bl, "        ");
 765 }
 766
 767 void transport_dump_vpd_proto_id(
 768         struct t10_vpd *vpd,
 769         unsigned char *p_buf,
 770         int p_buf_len)
 771 {
 772         unsigned char buf[VPD_TMP_BUF_SIZE];
 773         int len;
 774
 775         memset(buf, 0, VPD_TMP_BUF_SIZE);
 776         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 777
 778         switch (vpd->protocol_identifier) {
 779         case 0x00:
 780                 sprintf(buf+len, "Fibre Channel\n");
 781                 break;
 782         case 0x10:
 783                 sprintf(buf+len, "Parallel SCSI\n");
 784                 break;
 785         case 0x20:
 786                 sprintf(buf+len, "SSA\n");
 787                 break;
 788         case 0x30:
 789                 sprintf(buf+len, "IEEE 1394\n");
 790                 break;
 791         case 0x40:
 792                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 793                                 " Protocol\n");
 794                 break;
 795         case 0x50:
 796                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 797                 break;
 798         case 0x60:
 799                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 800                 break;
 801         case 0x70:
 802                 sprintf(buf+len, "Automation/Drive Interface Transport"
 803                                 " Protocol\n");
 804                 break;
 805         case 0x80:
 806                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 807                 break;
 808         default:
 809                 sprintf(buf+len, "Unknown 0x%02x\n",
 810                                 vpd->protocol_identifier);
 811                 break;
 812         }
 813
 814         if (p_buf)
 815                 strncpy(p_buf, buf, p_buf_len);
 816         else
 817                 pr_debug("%s", buf);
 818 }
 819
 820 void
 821 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 822 {
 823         /*
 824          * Check if the Protocol Identifier Valid (PIV) bit is set..
 825          *
 826          * from spc3r23.pdf section 7.5.1
 827          */
 828          if (page_83[1] & 0x80) {
 829                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 830                 vpd->protocol_identifier_set = 1;
 831                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 832         }
 833 }
 834 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 835
 836 int transport_dump_vpd_assoc(
 837         struct t10_vpd *vpd,
 838         unsigned char *p_buf,
 839         int p_buf_len)
 840 {
 841         unsigned char buf[VPD_TMP_BUF_SIZE];
 842         int ret = 0;
 843         int len;
 844
 845         memset(buf, 0, VPD_TMP_BUF_SIZE);
 846         len = sprintf(buf, "T10 VPD Identifier Association: ");
 847
 848         switch (vpd->association) {
 849         case 0x00:
 850                 sprintf(buf+len, "addressed logical unit\n");
 851                 break;
 852         case 0x10:
 853                 sprintf(buf+len, "target port\n");
 854                 break;
 855         case 0x20:
 856                 sprintf(buf+len, "SCSI target device\n");
 857                 break;
 858         default:
 859                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 860                 ret = -EINVAL;
 861                 break;
 862         }
 863
 864         if (p_buf)
 865                 strncpy(p_buf, buf, p_buf_len);
 866         else
 867                 pr_debug("%s", buf);
 868
 869         return ret;
 870 }
 871
 872 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 873 {
 874         /*
 875          * The VPD identification association..
 876          *
 877          * from spc3r23.pdf Section 7.6.3.1 Table 297
 878          */
 879         vpd->association = (page_83[1] & 0x30);
 880         return transport_dump_vpd_assoc(vpd, NULL, 0);
 881 }
 882 EXPORT_SYMBOL(transport_set_vpd_assoc);
 883
 884 int transport_dump_vpd_ident_type(
 885         struct t10_vpd *vpd,
 886         unsigned char *p_buf,
 887         int p_buf_len)
 888 {
 889         unsigned char buf[VPD_TMP_BUF_SIZE];
 890         int ret = 0;
 891         int len;
 892
 893         memset(buf, 0, VPD_TMP_BUF_SIZE);
 894         len = sprintf(buf, "T10 VPD Identifier Type: ");
 895
 896         switch (vpd->device_identifier_type) {
 897         case 0x00:
 898                 sprintf(buf+len, "Vendor specific\n");
 899                 break;
 900         case 0x01:
 901                 sprintf(buf+len, "T10 Vendor ID based\n");
 902                 break;
 903         case 0x02:
 904                 sprintf(buf+len, "EUI-64 based\n");
 905                 break;
 906         case 0x03:
 907                 sprintf(buf+len, "NAA\n");
 908                 break;
 909         case 0x04:
 910                 sprintf(buf+len, "Relative target port identifier\n");
 911                 break;
 912         case 0x08:
 913                 sprintf(buf+len, "SCSI name string\n");
 914                 break;
 915         default:
 916                 sprintf(buf+len, "Unsupported: 0x%02x\n",
 917                                 vpd->device_identifier_type);
 918                 ret = -EINVAL;
 919                 break;
 920         }
 921
 922         if (p_buf) {
 923                 if (p_buf_len < strlen(buf)+1)
 924                         return -EINVAL;
 925                 strncpy(p_buf, buf, p_buf_len);
 926         } else {
 927                 pr_debug("%s", buf);
 928         }
 929
 930         return ret;
 931 }
 932
 933 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
 934 {
 935         /*
 936          * The VPD identifier type..
 937          *
 938          * from spc3r23.pdf Section 7.6.3.1 Table 298
 939          */
 940         vpd->device_identifier_type = (page_83[1] & 0x0f);
 941         return transport_dump_vpd_ident_type(vpd, NULL, 0);
 942 }
 943 EXPORT_SYMBOL(transport_set_vpd_ident_type);
 944
 945 int transport_dump_vpd_ident(
 946         struct t10_vpd *vpd,
 947         unsigned char *p_buf,
 948         int p_buf_len)
 949 {
 950         unsigned char buf[VPD_TMP_BUF_SIZE];
 951         int ret = 0;
 952
 953         memset(buf, 0, VPD_TMP_BUF_SIZE);
 954
 955         switch (vpd->device_identifier_code_set) {
 956         case 0x01: /* Binary */
 957                 snprintf(buf, sizeof(buf),
 958                         "T10 VPD Binary Device Identifier: %s\n",
 959                         &vpd->device_identifier[0]);
 960                 break;
 961         case 0x02: /* ASCII */
 962                 snprintf(buf, sizeof(buf),
 963                         "T10 VPD ASCII Device Identifier: %s\n",
 964                         &vpd->device_identifier[0]);
 965                 break;
 966         case 0x03: /* UTF-8 */
 967                 snprintf(buf, sizeof(buf),
 968                         "T10 VPD UTF-8 Device Identifier: %s\n",
 969                         &vpd->device_identifier[0]);
 970                 break;
 971         default:
 972                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
 973                         " 0x%02x", vpd->device_identifier_code_set);
 974                 ret = -EINVAL;
 975                 break;
 976         }
 977
 978         if (p_buf)
 979                 strncpy(p_buf, buf, p_buf_len);
 980         else
 981                 pr_debug("%s", buf);
 982
 983         return ret;
 984 }
 985
 986 int
 987 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
 988 {
 989         static const char hex_str[] = "0123456789abcdef";
 990         int j = 0, i = 4; /* offset to start of the identifier */
 991
 992         /*
 993          * The VPD Code Set (encoding)
 994          *
 995          * from spc3r23.pdf Section 7.6.3.1 Table 296
 996          */
 997         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
 998         switch (vpd->device_identifier_code_set) {
 999         case 0x01: /* Binary */
1000                 vpd->device_identifier[j++] =
1001                                 hex_str[vpd->device_identifier_type];
1002                 while (i < (4 + page_83[3])) {
1003                         vpd->device_identifier[j++] =
1004                                 hex_str[(page_83[i] & 0xf0) >> 4];
1005                         vpd->device_identifier[j++] =
1006                                 hex_str[page_83[i] & 0x0f];
1007                         i++;
1008                 }
1009                 break;
1010         case 0x02: /* ASCII */
1011         case 0x03: /* UTF-8 */
1012                 while (i < (4 + page_83[3]))
1013                         vpd->device_identifier[j++] = page_83[i++];
1014                 break;
1015         default:
1016                 break;
1017         }
1018
1019         return transport_dump_vpd_ident(vpd, NULL, 0);
1020 }
1021 EXPORT_SYMBOL(transport_set_vpd_ident);
1022
1023 sense_reason_t
1024 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1025 {
1026         struct se_device *dev = cmd->se_dev;
1027
1028         if (cmd->unknown_data_length) {
1029                 cmd->data_length = size;
1030         } else if (size != cmd->data_length) {
1031                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1032                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1033                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1034                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1035
1036                 if (cmd->data_direction == DMA_TO_DEVICE) {
1037                         pr_err("Rejecting underflow/overflow"
1038                                         " WRITE data\n");
1039                         return TCM_INVALID_CDB_FIELD;
1040                 }
1041                 /*
1042                  * Reject READ_* or WRITE_* with overflow/underflow for
1043                  * type SCF_SCSI_DATA_CDB.
1044                  */
1045                 if (dev->dev_attrib.block_size != 512)  {
1046                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1047                                 " CDB on non 512-byte sector setup subsystem"
1048                                 " plugin: %s\n", dev->transport->name);
1049                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1050                         return TCM_INVALID_CDB_FIELD;
1051                 }
1052                 /*
1053                  * For the overflow case keep the existing fabric provided
1054                  * ->data_length.  Otherwise for the underflow case, reset
1055                  * ->data_length to the smaller SCSI expected data transfer
1056                  * length.
1057                  */
1058                 if (size > cmd->data_length) {
1059                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1060                         cmd->residual_count = (size - cmd->data_length);
1061                 } else {
1062                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1063                         cmd->residual_count = (cmd->data_length - size);
1064                         cmd->data_length = size;
1065                 }
1066         }
1067
1068         return 0;
1069
1070 }
1071
1072 /*
1073  * Used by fabric modules containing a local struct se_cmd within their
1074  * fabric dependent per I/O descriptor.
1075  */
1076 void transport_init_se_cmd(
1077         struct se_cmd *cmd,
1078         struct target_core_fabric_ops *tfo,
1079         struct se_session *se_sess,
1080         u32 data_length,
1081         int data_direction,
1082         int task_attr,
1083         unsigned char *sense_buffer)
1084 {
1085         INIT_LIST_HEAD(&cmd->se_lun_node);
1086         INIT_LIST_HEAD(&cmd->se_delayed_node);
1087         INIT_LIST_HEAD(&cmd->se_qf_node);
1088         INIT_LIST_HEAD(&cmd->se_cmd_list);
1089         INIT_LIST_HEAD(&cmd->state_list);
1090         init_completion(&cmd->transport_lun_fe_stop_comp);
1091         init_completion(&cmd->transport_lun_stop_comp);
1092         init_completion(&cmd->t_transport_stop_comp);
1093         init_completion(&cmd->cmd_wait_comp);
1094         init_completion(&cmd->task_stop_comp);
1095         spin_lock_init(&cmd->t_state_lock);
1096         cmd->transport_state = CMD_T_DEV_ACTIVE;
1097
1098         cmd->se_tfo = tfo;
1099         cmd->se_sess = se_sess;
1100         cmd->data_length = data_length;
1101         cmd->data_direction = data_direction;
1102         cmd->sam_task_attr = task_attr;
1103         cmd->sense_buffer = sense_buffer;
1104
1105         cmd->state_active = false;
1106 }
1107 EXPORT_SYMBOL(transport_init_se_cmd);
1108
1109 static sense_reason_t
1110 transport_check_alloc_task_attr(struct se_cmd *cmd)
1111 {
1112         struct se_device *dev = cmd->se_dev;
1113
1114         /*
1115          * Check if SAM Task Attribute emulation is enabled for this
1116          * struct se_device storage object
1117          */
1118         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1119                 return 0;
1120
1121         if (cmd->sam_task_attr == MSG_ACA_TAG) {
1122                 pr_debug("SAM Task Attribute ACA"
1123                         " emulation is not supported\n");
1124                 return TCM_INVALID_CDB_FIELD;
1125         }
1126         /*
1127          * Used to determine when ORDERED commands should go from
1128          * Dormant to Active status.
1129          */
1130         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1131         smp_mb__after_atomic_inc();
1132         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1133                         cmd->se_ordered_id, cmd->sam_task_attr,
1134                         dev->transport->name);
1135         return 0;
1136 }
1137
1138 sense_reason_t
1139 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1140 {
1141         struct se_device *dev = cmd->se_dev;
1142         sense_reason_t ret;
1143
1144         /*
1145          * Ensure that the received CDB is less than the max (252 + 8) bytes
1146          * for VARIABLE_LENGTH_CMD
1147          */
1148         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1149                 pr_err("Received SCSI CDB with command_size: %d that"
1150                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1151                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1152                 return TCM_INVALID_CDB_FIELD;
1153         }
1154         /*
1155          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1156          * allocate the additional extended CDB buffer now..  Otherwise
1157          * setup the pointer from __t_task_cdb to t_task_cdb.
1158          */
1159         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1160                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1161                                                 GFP_KERNEL);
1162                 if (!cmd->t_task_cdb) {
1163                         pr_err("Unable to allocate cmd->t_task_cdb"
1164                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1165                                 scsi_command_size(cdb),
1166                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1167                         return TCM_OUT_OF_RESOURCES;
1168                 }
1169         } else
1170                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1171         /*
1172          * Copy the original CDB into cmd->
1173          */
1174         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1175
1176         trace_target_sequencer_start(cmd);
1177
1178         /*
1179          * Check for an existing UNIT ATTENTION condition
1180          */
1181         ret = target_scsi3_ua_check(cmd);
1182         if (ret)
1183                 return ret;
1184
1185         ret = target_alua_state_check(cmd);
1186         if (ret)
1187                 return ret;
1188
1189         ret = target_check_reservation(cmd);
1190         if (ret) {
1191                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1192                 return ret;
1193         }
1194
1195         ret = dev->transport->parse_cdb(cmd);
1196         if (ret)
1197                 return ret;
1198
1199         ret = transport_check_alloc_task_attr(cmd);
1200         if (ret)
1201                 return ret;
1202
1203         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1204
1205         spin_lock(&cmd->se_lun->lun_sep_lock);
1206         if (cmd->se_lun->lun_sep)
1207                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1208         spin_unlock(&cmd->se_lun->lun_sep_lock);
1209         return 0;
1210 }
1211 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1212
1213 /*
1214  * Used by fabric module frontends to queue tasks directly.
1215  * Many only be used from process context only
1216  */
1217 int transport_handle_cdb_direct(
1218         struct se_cmd *cmd)
1219 {
1220         sense_reason_t ret;
1221
1222         if (!cmd->se_lun) {
1223                 dump_stack();
1224                 pr_err("cmd->se_lun is NULL\n");
1225                 return -EINVAL;
1226         }
1227         if (in_interrupt()) {
1228                 dump_stack();
1229                 pr_err("transport_generic_handle_cdb cannot be called"
1230                                 " from interrupt context\n");
1231                 return -EINVAL;
1232         }
1233         /*
1234          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1235          * outstanding descriptors are handled correctly during shutdown via
1236          * transport_wait_for_tasks()
1237          *
1238          * Also, we don't take cmd->t_state_lock here as we only expect
1239          * this to be called for initial descriptor submission.
1240          */
1241         cmd->t_state = TRANSPORT_NEW_CMD;
1242         cmd->transport_state |= CMD_T_ACTIVE;
1243
1244         /*
1245          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1246          * so follow TRANSPORT_NEW_CMD processing thread context usage
1247          * and call transport_generic_request_failure() if necessary..
1248          */
1249         ret = transport_generic_new_cmd(cmd);
1250         if (ret)
1251                 transport_generic_request_failure(cmd, ret);
1252         return 0;
1253 }
1254 EXPORT_SYMBOL(transport_handle_cdb_direct);
1255
1256 sense_reason_t
1257 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1258                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1259 {
1260         if (!sgl || !sgl_count)
1261                 return 0;
1262
1263         /*
1264          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1265          * scatterlists already have been set to follow what the fabric
1266          * passes for the original expected data transfer length.
1267          */
1268         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1269                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1270                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1271                 return TCM_INVALID_CDB_FIELD;
1272         }
1273
1274         cmd->t_data_sg = sgl;
1275         cmd->t_data_nents = sgl_count;
1276
1277         if (sgl_bidi && sgl_bidi_count) {
1278                 cmd->t_bidi_data_sg = sgl_bidi;
1279                 cmd->t_bidi_data_nents = sgl_bidi_count;
1280         }
1281         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1282         return 0;
1283 }
1284
1285 /*
1286  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1287  *                       se_cmd + use pre-allocated SGL memory.
1288  *
1289  * @se_cmd: command descriptor to submit
1290  * @se_sess: associated se_sess for endpoint
1291  * @cdb: pointer to SCSI CDB
1292  * @sense: pointer to SCSI sense buffer
1293  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1294  * @data_length: fabric expected data transfer length
1295  * @task_addr: SAM task attribute
1296  * @data_dir: DMA data direction
1297  * @flags: flags for command submission from target_sc_flags_tables
1298  * @sgl: struct scatterlist memory for unidirectional mapping
1299  * @sgl_count: scatterlist count for unidirectional mapping
1300  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1301  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1302  *
1303  * Returns non zero to signal active I/O shutdown failure.  All other
1304  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1305  * but still return zero here.
1306  *
1307  * This may only be called from process context, and also currently
1308  * assumes internal allocation of fabric payload buffer by target-core.
1309  */
1310 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1311                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1312                 u32 data_length, int task_attr, int data_dir, int flags,
1313                 struct scatterlist *sgl, u32 sgl_count,
1314                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1315 {
1316         struct se_portal_group *se_tpg;
1317         sense_reason_t rc;
1318         int ret;
1319
1320         se_tpg = se_sess->se_tpg;
1321         BUG_ON(!se_tpg);
1322         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1323         BUG_ON(in_interrupt());
1324         /*
1325          * Initialize se_cmd for target operation.  From this point
1326          * exceptions are handled by sending exception status via
1327          * target_core_fabric_ops->queue_status() callback
1328          */
1329         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1330                                 data_length, data_dir, task_attr, sense);
1331         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1332                 se_cmd->unknown_data_length = 1;
1333         /*
1334          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1335          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1336          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1337          * kref_put() to happen during fabric packet acknowledgement.
1338          */
1339         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1340         if (ret)
1341                 return ret;
1342         /*
1343          * Signal bidirectional data payloads to target-core
1344          */
1345         if (flags & TARGET_SCF_BIDI_OP)
1346                 se_cmd->se_cmd_flags |= SCF_BIDI;
1347         /*
1348          * Locate se_lun pointer and attach it to struct se_cmd
1349          */
1350         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1351         if (rc) {
1352                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1353                 target_put_sess_cmd(se_sess, se_cmd);
1354                 return 0;
1355         }
1356
1357         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1358         if (rc != 0) {
1359                 transport_generic_request_failure(se_cmd, rc);
1360                 return 0;
1361         }
1362         /*
1363          * When a non zero sgl_count has been passed perform SGL passthrough
1364          * mapping for pre-allocated fabric memory instead of having target
1365          * core perform an internal SGL allocation..
1366          */
1367         if (sgl_count != 0) {
1368                 BUG_ON(!sgl);
1369
1370                 /*
1371                  * A work-around for tcm_loop as some userspace code via
1372                  * scsi-generic do not memset their associated read buffers,
1373                  * so go ahead and do that here for type non-data CDBs.  Also
1374                  * note that this is currently guaranteed to be a single SGL
1375                  * for this case by target core in target_setup_cmd_from_cdb()
1376                  * -> transport_generic_cmd_sequencer().
1377                  */
1378                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1379                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1380                         unsigned char *buf = NULL;
1381
1382                         if (sgl)
1383                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1384
1385                         if (buf) {
1386                                 memset(buf, 0, sgl->length);
1387                                 kunmap(sg_page(sgl));
1388                         }
1389                 }
1390
1391                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1392                                 sgl_bidi, sgl_bidi_count);
1393                 if (rc != 0) {
1394                         transport_generic_request_failure(se_cmd, rc);
1395                         return 0;
1396                 }
1397         }
1398         /*
1399          * Check if we need to delay processing because of ALUA
1400          * Active/NonOptimized primary access state..
1401          */
1402         core_alua_check_nonop_delay(se_cmd);
1403
1404         transport_handle_cdb_direct(se_cmd);
1405         return 0;
1406 }
1407 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1408
1409 /*
1410  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1411  *
1412  * @se_cmd: command descriptor to submit
1413  * @se_sess: associated se_sess for endpoint
1414  * @cdb: pointer to SCSI CDB
1415  * @sense: pointer to SCSI sense buffer
1416  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1417  * @data_length: fabric expected data transfer length
1418  * @task_addr: SAM task attribute
1419  * @data_dir: DMA data direction
1420  * @flags: flags for command submission from target_sc_flags_tables
1421  *
1422  * Returns non zero to signal active I/O shutdown failure.  All other
1423  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1424  * but still return zero here.
1425  *
1426  * This may only be called from process context, and also currently
1427  * assumes internal allocation of fabric payload buffer by target-core.
1428  *
1429  * It also assumes interal target core SGL memory allocation.
1430  */
1431 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1432                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1433                 u32 data_length, int task_attr, int data_dir, int flags)
1434 {
1435         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1436                         unpacked_lun, data_length, task_attr, data_dir,
1437                         flags, NULL, 0, NULL, 0);
1438 }
1439 EXPORT_SYMBOL(target_submit_cmd);
1440
1441 static void target_complete_tmr_failure(struct work_struct *work)
1442 {
1443         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1444
1445         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1446         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1447
1448         transport_cmd_check_stop_to_fabric(se_cmd);
1449 }
1450
1451 /**
1452  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1453  *                     for TMR CDBs
1454  *
1455  * @se_cmd: command descriptor to submit
1456  * @se_sess: associated se_sess for endpoint
1457  * @sense: pointer to SCSI sense buffer
1458  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1459  * @fabric_context: fabric context for TMR req
1460  * @tm_type: Type of TM request
1461  * @gfp: gfp type for caller
1462  * @tag: referenced task tag for TMR_ABORT_TASK
1463  * @flags: submit cmd flags
1464  *
1465  * Callable from all contexts.
1466  **/
1467
1468 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1469                 unsigned char *sense, u32 unpacked_lun,
1470                 void *fabric_tmr_ptr, unsigned char tm_type,
1471                 gfp_t gfp, unsigned int tag, int flags)
1472 {
1473         struct se_portal_group *se_tpg;
1474         int ret;
1475
1476         se_tpg = se_sess->se_tpg;
1477         BUG_ON(!se_tpg);
1478
1479         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1480                               0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1481         /*
1482          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1483          * allocation failure.
1484          */
1485         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1486         if (ret < 0)
1487                 return -ENOMEM;
1488
1489         if (tm_type == TMR_ABORT_TASK)
1490                 se_cmd->se_tmr_req->ref_task_tag = tag;
1491
1492         /* See target_submit_cmd for commentary */
1493         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1494         if (ret) {
1495                 core_tmr_release_req(se_cmd->se_tmr_req);
1496                 return ret;
1497         }
1498
1499         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1500         if (ret) {
1501                 /*
1502                  * For callback during failure handling, push this work off
1503                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1504                  */
1505                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1506                 schedule_work(&se_cmd->work);
1507                 return 0;
1508         }
1509         transport_generic_handle_tmr(se_cmd);
1510         return 0;
1511 }
1512 EXPORT_SYMBOL(target_submit_tmr);
1513
1514 /*
1515  * If the cmd is active, request it to be stopped and sleep until it
1516  * has completed.
1517  */
1518 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1519 {
1520         bool was_active = false;
1521
1522         if (cmd->transport_state & CMD_T_BUSY) {
1523                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1524                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1525
1526                 pr_debug("cmd %p waiting to complete\n", cmd);
1527                 wait_for_completion(&cmd->task_stop_comp);
1528                 pr_debug("cmd %p stopped successfully\n", cmd);
1529
1530                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1531                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1532                 cmd->transport_state &= ~CMD_T_BUSY;
1533                 was_active = true;
1534         }
1535
1536         return was_active;
1537 }
1538
1539 /*
1540  * Handle SAM-esque emulation for generic transport request failures.
1541  */
1542 void transport_generic_request_failure(struct se_cmd *cmd,
1543                 sense_reason_t sense_reason)
1544 {
1545         int ret = 0;
1546
1547         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1548                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1549                 cmd->t_task_cdb[0]);
1550         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1551                 cmd->se_tfo->get_cmd_state(cmd),
1552                 cmd->t_state, sense_reason);
1553         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1554                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1555                 (cmd->transport_state & CMD_T_STOP) != 0,
1556                 (cmd->transport_state & CMD_T_SENT) != 0);
1557
1558         /*
1559          * For SAM Task Attribute emulation for failed struct se_cmd
1560          */
1561         transport_complete_task_attr(cmd);
1562         /*
1563          * Handle special case for COMPARE_AND_WRITE failure, where the
1564          * callback is expected to drop the per device ->caw_mutex.
1565          */
1566         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1567              cmd->transport_complete_callback)
1568                 cmd->transport_complete_callback(cmd);
1569
1570         switch (sense_reason) {
1571         case TCM_NON_EXISTENT_LUN:
1572         case TCM_UNSUPPORTED_SCSI_OPCODE:
1573         case TCM_INVALID_CDB_FIELD:
1574         case TCM_INVALID_PARAMETER_LIST:
1575         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1576         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1577         case TCM_UNKNOWN_MODE_PAGE:
1578         case TCM_WRITE_PROTECTED:
1579         case TCM_ADDRESS_OUT_OF_RANGE:
1580         case TCM_CHECK_CONDITION_ABORT_CMD:
1581         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1582         case TCM_CHECK_CONDITION_NOT_READY:
1583                 break;
1584         case TCM_OUT_OF_RESOURCES:
1585                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1586                 break;
1587         case TCM_RESERVATION_CONFLICT:
1588                 /*
1589                  * No SENSE Data payload for this case, set SCSI Status
1590                  * and queue the response to $FABRIC_MOD.
1591                  *
1592                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1593                  */
1594                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1595                 /*
1596                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1597                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1598                  * CONFLICT STATUS.
1599                  *
1600                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1601                  */
1602                 if (cmd->se_sess &&
1603                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1604                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1605                                 cmd->orig_fe_lun, 0x2C,
1606                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1607
1608                 trace_target_cmd_complete(cmd);
1609                 ret = cmd->se_tfo-> queue_status(cmd);
1610                 if (ret == -EAGAIN || ret == -ENOMEM)
1611                         goto queue_full;
1612                 goto check_stop;
1613         default:
1614                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1615                         cmd->t_task_cdb[0], sense_reason);
1616                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1617                 break;
1618         }
1619
1620         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1621         if (ret == -EAGAIN || ret == -ENOMEM)
1622                 goto queue_full;
1623
1624 check_stop:
1625         transport_lun_remove_cmd(cmd);
1626         if (!transport_cmd_check_stop_to_fabric(cmd))
1627                 ;
1628         return;
1629
1630 queue_full:
1631         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1632         transport_handle_queue_full(cmd, cmd->se_dev);
1633 }
1634 EXPORT_SYMBOL(transport_generic_request_failure);
1635
1636 void __target_execute_cmd(struct se_cmd *cmd)
1637 {
1638         sense_reason_t ret;
1639
1640         if (cmd->execute_cmd) {
1641                 ret = cmd->execute_cmd(cmd);
1642                 if (ret) {
1643                         spin_lock_irq(&cmd->t_state_lock);
1644                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1645                         spin_unlock_irq(&cmd->t_state_lock);
1646
1647                         transport_generic_request_failure(cmd, ret);
1648                 }
1649         }
1650 }
1651
1652 static bool target_handle_task_attr(struct se_cmd *cmd)
1653 {
1654         struct se_device *dev = cmd->se_dev;
1655
1656         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1657                 return false;
1658
1659         /*
1660          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1661          * to allow the passed struct se_cmd list of tasks to the front of the list.
1662          */
1663         switch (cmd->sam_task_attr) {
1664         case MSG_HEAD_TAG:
1665                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1666                          "se_ordered_id: %u\n",
1667                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1668                 return false;
1669         case MSG_ORDERED_TAG:
1670                 atomic_inc(&dev->dev_ordered_sync);
1671                 smp_mb__after_atomic_inc();
1672
1673                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1674                          " se_ordered_id: %u\n",
1675                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1676
1677                 /*
1678                  * Execute an ORDERED command if no other older commands
1679                  * exist that need to be completed first.
1680                  */
1681                 if (!atomic_read(&dev->simple_cmds))
1682                         return false;
1683                 break;
1684         default:
1685                 /*
1686                  * For SIMPLE and UNTAGGED Task Attribute commands
1687                  */
1688                 atomic_inc(&dev->simple_cmds);
1689                 smp_mb__after_atomic_inc();
1690                 break;
1691         }
1692
1693         if (atomic_read(&dev->dev_ordered_sync) == 0)
1694                 return false;
1695
1696         spin_lock(&dev->delayed_cmd_lock);
1697         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1698         spin_unlock(&dev->delayed_cmd_lock);
1699
1700         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1701                 " delayed CMD list, se_ordered_id: %u\n",
1702                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1703                 cmd->se_ordered_id);
1704         return true;
1705 }
1706
1707 void target_execute_cmd(struct se_cmd *cmd)
1708 {
1709         /*
1710          * If the received CDB has aleady been aborted stop processing it here.
1711          */
1712         if (transport_check_aborted_status(cmd, 1)) {
1713                 complete(&cmd->transport_lun_stop_comp);
1714                 return;
1715         }
1716
1717         /*
1718          * Determine if IOCTL context caller in requesting the stopping of this
1719          * command for LUN shutdown purposes.
1720          */
1721         spin_lock_irq(&cmd->t_state_lock);
1722         if (cmd->transport_state & CMD_T_LUN_STOP) {
1723                 pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
1724                         __func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
1725
1726                 cmd->transport_state &= ~CMD_T_ACTIVE;
1727                 spin_unlock_irq(&cmd->t_state_lock);
1728                 complete(&cmd->transport_lun_stop_comp);
1729                 return;
1730         }
1731         /*
1732          * Determine if frontend context caller is requesting the stopping of
1733          * this command for frontend exceptions.
1734          */
1735         if (cmd->transport_state & CMD_T_STOP) {
1736                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1737                         __func__, __LINE__,
1738                         cmd->se_tfo->get_task_tag(cmd));
1739
1740                 spin_unlock_irq(&cmd->t_state_lock);
1741                 complete(&cmd->t_transport_stop_comp);
1742                 return;
1743         }
1744
1745         cmd->t_state = TRANSPORT_PROCESSING;
1746         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1747         spin_unlock_irq(&cmd->t_state_lock);
1748
1749         if (target_handle_task_attr(cmd)) {
1750                 spin_lock_irq(&cmd->t_state_lock);
1751                 cmd->transport_state &= ~CMD_T_BUSY|CMD_T_SENT;
1752                 spin_unlock_irq(&cmd->t_state_lock);
1753                 return;
1754         }
1755
1756         __target_execute_cmd(cmd);
1757 }
1758 EXPORT_SYMBOL(target_execute_cmd);
1759
1760 /*
1761  * Process all commands up to the last received ORDERED task attribute which
1762  * requires another blocking boundary
1763  */
1764 static void target_restart_delayed_cmds(struct se_device *dev)
1765 {
1766         for (;;) {
1767                 struct se_cmd *cmd;
1768
1769                 spin_lock(&dev->delayed_cmd_lock);
1770                 if (list_empty(&dev->delayed_cmd_list)) {
1771                         spin_unlock(&dev->delayed_cmd_lock);
1772                         break;
1773                 }
1774
1775                 cmd = list_entry(dev->delayed_cmd_list.next,
1776                                  struct se_cmd, se_delayed_node);
1777                 list_del(&cmd->se_delayed_node);
1778                 spin_unlock(&dev->delayed_cmd_lock);
1779
1780                 __target_execute_cmd(cmd);
1781
1782                 if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1783                         break;
1784         }
1785 }
1786
1787 /*
1788  * Called from I/O completion to determine which dormant/delayed
1789  * and ordered cmds need to have their tasks added to the execution queue.
1790  */
1791 static void transport_complete_task_attr(struct se_cmd *cmd)
1792 {
1793         struct se_device *dev = cmd->se_dev;
1794
1795         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1796                 return;
1797
1798         if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1799                 atomic_dec(&dev->simple_cmds);
1800                 smp_mb__after_atomic_dec();
1801                 dev->dev_cur_ordered_id++;
1802                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1803                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1804                         cmd->se_ordered_id);
1805         } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1806                 dev->dev_cur_ordered_id++;
1807                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1808                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1809                         cmd->se_ordered_id);
1810         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1811                 atomic_dec(&dev->dev_ordered_sync);
1812                 smp_mb__after_atomic_dec();
1813
1814                 dev->dev_cur_ordered_id++;
1815                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1816                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1817         }
1818
1819         target_restart_delayed_cmds(dev);
1820 }
1821
1822 static void transport_complete_qf(struct se_cmd *cmd)
1823 {
1824         int ret = 0;
1825
1826         transport_complete_task_attr(cmd);
1827
1828         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1829                 trace_target_cmd_complete(cmd);
1830                 ret = cmd->se_tfo->queue_status(cmd);
1831                 if (ret)
1832                         goto out;
1833         }
1834
1835         switch (cmd->data_direction) {
1836         case DMA_FROM_DEVICE:
1837                 trace_target_cmd_complete(cmd);
1838                 ret = cmd->se_tfo->queue_data_in(cmd);
1839                 break;
1840         case DMA_TO_DEVICE:
1841                 if (cmd->se_cmd_flags & SCF_BIDI) {
1842                         ret = cmd->se_tfo->queue_data_in(cmd);
1843                         if (ret < 0)
1844                                 break;
1845                 }
1846                 /* Fall through for DMA_TO_DEVICE */
1847         case DMA_NONE:
1848                 trace_target_cmd_complete(cmd);
1849                 ret = cmd->se_tfo->queue_status(cmd);
1850                 break;
1851         default:
1852                 break;
1853         }
1854
1855 out:
1856         if (ret < 0) {
1857                 transport_handle_queue_full(cmd, cmd->se_dev);
1858                 return;
1859         }
1860         transport_lun_remove_cmd(cmd);
1861         transport_cmd_check_stop_to_fabric(cmd);
1862 }
1863
1864 static void transport_handle_queue_full(
1865         struct se_cmd *cmd,
1866         struct se_device *dev)
1867 {
1868         spin_lock_irq(&dev->qf_cmd_lock);
1869         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1870         atomic_inc(&dev->dev_qf_count);
1871         smp_mb__after_atomic_inc();
1872         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1873
1874         schedule_work(&cmd->se_dev->qf_work_queue);
1875 }
1876
1877 static void target_complete_ok_work(struct work_struct *work)
1878 {
1879         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1880         int ret;
1881
1882         /*
1883          * Check if we need to move delayed/dormant tasks from cmds on the
1884          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1885          * Attribute.
1886          */
1887         transport_complete_task_attr(cmd);
1888
1889         /*
1890          * Check to schedule QUEUE_FULL work, or execute an existing
1891          * cmd->transport_qf_callback()
1892          */
1893         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1894                 schedule_work(&cmd->se_dev->qf_work_queue);
1895
1896         /*
1897          * Check if we need to send a sense buffer from
1898          * the struct se_cmd in question.
1899          */
1900         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1901                 WARN_ON(!cmd->scsi_status);
1902                 ret = transport_send_check_condition_and_sense(
1903                                         cmd, 0, 1);
1904                 if (ret == -EAGAIN || ret == -ENOMEM)
1905                         goto queue_full;
1906
1907                 transport_lun_remove_cmd(cmd);
1908                 transport_cmd_check_stop_to_fabric(cmd);
1909                 return;
1910         }
1911         /*
1912          * Check for a callback, used by amongst other things
1913          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
1914          */
1915         if (cmd->transport_complete_callback) {
1916                 sense_reason_t rc;
1917
1918                 rc = cmd->transport_complete_callback(cmd);
1919                 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
1920                         return;
1921                 } else if (rc) {
1922                         ret = transport_send_check_condition_and_sense(cmd,
1923                                                 rc, 0);
1924                         if (ret == -EAGAIN || ret == -ENOMEM)
1925                                 goto queue_full;
1926
1927                         transport_lun_remove_cmd(cmd);
1928                         transport_cmd_check_stop_to_fabric(cmd);
1929                         return;
1930                 }
1931         }
1932
1933         switch (cmd->data_direction) {
1934         case DMA_FROM_DEVICE:
1935                 spin_lock(&cmd->se_lun->lun_sep_lock);
1936                 if (cmd->se_lun->lun_sep) {
1937                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1938                                         cmd->data_length;
1939                 }
1940                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1941
1942                 trace_target_cmd_complete(cmd);
1943                 ret = cmd->se_tfo->queue_data_in(cmd);
1944                 if (ret == -EAGAIN || ret == -ENOMEM)
1945                         goto queue_full;
1946                 break;
1947         case DMA_TO_DEVICE:
1948                 spin_lock(&cmd->se_lun->lun_sep_lock);
1949                 if (cmd->se_lun->lun_sep) {
1950                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
1951                                 cmd->data_length;
1952                 }
1953                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1954                 /*
1955                  * Check if we need to send READ payload for BIDI-COMMAND
1956                  */
1957                 if (cmd->se_cmd_flags & SCF_BIDI) {
1958                         spin_lock(&cmd->se_lun->lun_sep_lock);
1959                         if (cmd->se_lun->lun_sep) {
1960                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1961                                         cmd->data_length;
1962                         }
1963                         spin_unlock(&cmd->se_lun->lun_sep_lock);
1964                         ret = cmd->se_tfo->queue_data_in(cmd);
1965                         if (ret == -EAGAIN || ret == -ENOMEM)
1966                                 goto queue_full;
1967                         break;
1968                 }
1969                 /* Fall through for DMA_TO_DEVICE */
1970         case DMA_NONE:
1971                 trace_target_cmd_complete(cmd);
1972                 ret = cmd->se_tfo->queue_status(cmd);
1973                 if (ret == -EAGAIN || ret == -ENOMEM)
1974                         goto queue_full;
1975                 break;
1976         default:
1977                 break;
1978         }
1979
1980         transport_lun_remove_cmd(cmd);
1981         transport_cmd_check_stop_to_fabric(cmd);
1982         return;
1983
1984 queue_full:
1985         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
1986                 " data_direction: %d\n", cmd, cmd->data_direction);
1987         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1988         transport_handle_queue_full(cmd, cmd->se_dev);
1989 }
1990
1991 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
1992 {
1993         struct scatterlist *sg;
1994         int count;
1995
1996         for_each_sg(sgl, sg, nents, count)
1997                 __free_page(sg_page(sg));
1998
1999         kfree(sgl);
2000 }
2001
2002 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2003 {
2004         /*
2005          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2006          * emulation, and free + reset pointers if necessary..
2007          */
2008         if (!cmd->t_data_sg_orig)
2009                 return;
2010
2011         kfree(cmd->t_data_sg);
2012         cmd->t_data_sg = cmd->t_data_sg_orig;
2013         cmd->t_data_sg_orig = NULL;
2014         cmd->t_data_nents = cmd->t_data_nents_orig;
2015         cmd->t_data_nents_orig = 0;
2016 }
2017
2018 static inline void transport_free_pages(struct se_cmd *cmd)
2019 {
2020         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2021                 transport_reset_sgl_orig(cmd);
2022                 return;
2023         }
2024         transport_reset_sgl_orig(cmd);
2025
2026         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2027         cmd->t_data_sg = NULL;
2028         cmd->t_data_nents = 0;
2029
2030         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2031         cmd->t_bidi_data_sg = NULL;
2032         cmd->t_bidi_data_nents = 0;
2033 }
2034
2035 /**
2036  * transport_release_cmd - free a command
2037  * @cmd:       command to free
2038  *
2039  * This routine unconditionally frees a command, and reference counting
2040  * or list removal must be done in the caller.
2041  */
2042 static int transport_release_cmd(struct se_cmd *cmd)
2043 {
2044         BUG_ON(!cmd->se_tfo);
2045
2046         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2047                 core_tmr_release_req(cmd->se_tmr_req);
2048         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2049                 kfree(cmd->t_task_cdb);
2050         /*
2051          * If this cmd has been setup with target_get_sess_cmd(), drop
2052          * the kref and call ->release_cmd() in kref callback.
2053          */
2054         return target_put_sess_cmd(cmd->se_sess, cmd);
2055 }
2056
2057 /**
2058  * transport_put_cmd - release a reference to a command
2059  * @cmd:       command to release
2060  *
2061  * This routine releases our reference to the command and frees it if possible.
2062  */
2063 static int transport_put_cmd(struct se_cmd *cmd)
2064 {
2065         transport_free_pages(cmd);
2066         return transport_release_cmd(cmd);
2067 }
2068
2069 void *transport_kmap_data_sg(struct se_cmd *cmd)
2070 {
2071         struct scatterlist *sg = cmd->t_data_sg;
2072         struct page **pages;
2073         int i;
2074
2075         /*
2076          * We need to take into account a possible offset here for fabrics like
2077          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2078          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2079          */
2080         if (!cmd->t_data_nents)
2081                 return NULL;
2082
2083         BUG_ON(!sg);
2084         if (cmd->t_data_nents == 1)
2085                 return kmap(sg_page(sg)) + sg->offset;
2086
2087         /* >1 page. use vmap */
2088         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2089         if (!pages)
2090                 return NULL;
2091
2092         /* convert sg[] to pages[] */
2093         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2094                 pages[i] = sg_page(sg);
2095         }
2096
2097         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2098         kfree(pages);
2099         if (!cmd->t_data_vmap)
2100                 return NULL;
2101
2102         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2103 }
2104 EXPORT_SYMBOL(transport_kmap_data_sg);
2105
2106 void transport_kunmap_data_sg(struct se_cmd *cmd)
2107 {
2108         if (!cmd->t_data_nents) {
2109                 return;
2110         } else if (cmd->t_data_nents == 1) {
2111                 kunmap(sg_page(cmd->t_data_sg));
2112                 return;
2113         }
2114
2115         vunmap(cmd->t_data_vmap);
2116         cmd->t_data_vmap = NULL;
2117 }
2118 EXPORT_SYMBOL(transport_kunmap_data_sg);
2119
2120 int
2121 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2122                  bool zero_page)
2123 {
2124         struct scatterlist *sg;
2125         struct page *page;
2126         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2127         unsigned int nent;
2128         int i = 0;
2129
2130         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2131         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2132         if (!sg)
2133                 return -ENOMEM;
2134
2135         sg_init_table(sg, nent);
2136
2137         while (length) {
2138                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2139                 page = alloc_page(GFP_KERNEL | zero_flag);
2140                 if (!page)
2141                         goto out;
2142
2143                 sg_set_page(&sg[i], page, page_len, 0);
2144                 length -= page_len;
2145                 i++;
2146         }
2147         *sgl = sg;
2148         *nents = nent;
2149         return 0;
2150
2151 out:
2152         while (i > 0) {
2153                 i--;
2154                 __free_page(sg_page(&sg[i]));
2155         }
2156         kfree(sg);
2157         return -ENOMEM;
2158 }
2159
2160 /*
2161  * Allocate any required resources to execute the command.  For writes we
2162  * might not have the payload yet, so notify the fabric via a call to
2163  * ->write_pending instead. Otherwise place it on the execution queue.
2164  */
2165 sense_reason_t
2166 transport_generic_new_cmd(struct se_cmd *cmd)
2167 {
2168         int ret = 0;
2169
2170         /*
2171          * Determine is the TCM fabric module has already allocated physical
2172          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2173          * beforehand.
2174          */
2175         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2176             cmd->data_length) {
2177                 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2178
2179                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2180                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2181                         u32 bidi_length;
2182
2183                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2184                                 bidi_length = cmd->t_task_nolb *
2185                                               cmd->se_dev->dev_attrib.block_size;
2186                         else
2187                                 bidi_length = cmd->data_length;
2188
2189                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2190                                                &cmd->t_bidi_data_nents,
2191                                                bidi_length, zero_flag);
2192                         if (ret < 0)
2193                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2194                 }
2195
2196                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2197                                        cmd->data_length, zero_flag);
2198                 if (ret < 0)
2199                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2200         }
2201         /*
2202          * If this command is not a write we can execute it right here,
2203          * for write buffers we need to notify the fabric driver first
2204          * and let it call back once the write buffers are ready.
2205          */
2206         target_add_to_state_list(cmd);
2207         if (cmd->data_direction != DMA_TO_DEVICE) {
2208                 target_execute_cmd(cmd);
2209                 return 0;
2210         }
2211         transport_cmd_check_stop(cmd, false, true);
2212
2213         ret = cmd->se_tfo->write_pending(cmd);
2214         if (ret == -EAGAIN || ret == -ENOMEM)
2215                 goto queue_full;
2216
2217         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2218         WARN_ON(ret);
2219
2220         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2221
2222 queue_full:
2223         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2224         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2225         transport_handle_queue_full(cmd, cmd->se_dev);
2226         return 0;
2227 }
2228 EXPORT_SYMBOL(transport_generic_new_cmd);
2229
2230 static void transport_write_pending_qf(struct se_cmd *cmd)
2231 {
2232         int ret;
2233
2234         ret = cmd->se_tfo->write_pending(cmd);
2235         if (ret == -EAGAIN || ret == -ENOMEM) {
2236                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2237                          cmd);
2238                 transport_handle_queue_full(cmd, cmd->se_dev);
2239         }
2240 }
2241
2242 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2243 {
2244         unsigned long flags;
2245         int ret = 0;
2246
2247         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2248                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2249                          transport_wait_for_tasks(cmd);
2250
2251                 ret = transport_release_cmd(cmd);
2252         } else {
2253                 if (wait_for_tasks)
2254                         transport_wait_for_tasks(cmd);
2255                 /*
2256                  * Handle WRITE failure case where transport_generic_new_cmd()
2257                  * has already added se_cmd to state_list, but fabric has
2258                  * failed command before I/O submission.
2259                  */
2260                 if (cmd->state_active) {
2261                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2262                         target_remove_from_state_list(cmd);
2263                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2264                 }
2265
2266                 if (cmd->se_lun)
2267                         transport_lun_remove_cmd(cmd);
2268
2269                 ret = transport_put_cmd(cmd);
2270         }
2271         return ret;
2272 }
2273 EXPORT_SYMBOL(transport_generic_free_cmd);
2274
2275 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2276  * @se_sess:    session to reference
2277  * @se_cmd:     command descriptor to add
2278  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2279  */
2280 int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2281                                bool ack_kref)
2282 {
2283         unsigned long flags;
2284         int ret = 0;
2285
2286         kref_init(&se_cmd->cmd_kref);
2287         /*
2288          * Add a second kref if the fabric caller is expecting to handle
2289          * fabric acknowledgement that requires two target_put_sess_cmd()
2290          * invocations before se_cmd descriptor release.
2291          */
2292         if (ack_kref == true) {
2293                 kref_get(&se_cmd->cmd_kref);
2294                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2295         }
2296
2297         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2298         if (se_sess->sess_tearing_down) {
2299                 ret = -ESHUTDOWN;
2300                 goto out;
2301         }
2302         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2303 out:
2304         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2305         return ret;
2306 }
2307 EXPORT_SYMBOL(target_get_sess_cmd);
2308
2309 static void target_release_cmd_kref(struct kref *kref)
2310 {
2311         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2312         struct se_session *se_sess = se_cmd->se_sess;
2313
2314         if (list_empty(&se_cmd->se_cmd_list)) {
2315                 spin_unlock(&se_sess->sess_cmd_lock);
2316                 se_cmd->se_tfo->release_cmd(se_cmd);
2317                 return;
2318         }
2319         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2320                 spin_unlock(&se_sess->sess_cmd_lock);
2321                 complete(&se_cmd->cmd_wait_comp);
2322                 return;
2323         }
2324         list_del(&se_cmd->se_cmd_list);
2325         spin_unlock(&se_sess->sess_cmd_lock);
2326
2327         se_cmd->se_tfo->release_cmd(se_cmd);
2328 }
2329
2330 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2331  * @se_sess:    session to reference
2332  * @se_cmd:     command descriptor to drop
2333  */
2334 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2335 {
2336         return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2337                         &se_sess->sess_cmd_lock);
2338 }
2339 EXPORT_SYMBOL(target_put_sess_cmd);
2340
2341 /* target_sess_cmd_list_set_waiting - Flag all commands in
2342  *         sess_cmd_list to complete cmd_wait_comp.  Set
2343  *         sess_tearing_down so no more commands are queued.
2344  * @se_sess:    session to flag
2345  */
2346 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2347 {
2348         struct se_cmd *se_cmd;
2349         unsigned long flags;
2350
2351         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2352         if (se_sess->sess_tearing_down) {
2353                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2354                 return;
2355         }
2356         se_sess->sess_tearing_down = 1;
2357         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2358
2359         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2360                 se_cmd->cmd_wait_set = 1;
2361
2362         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2363 }
2364 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2365
2366 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2367  * @se_sess:    session to wait for active I/O
2368  */
2369 void target_wait_for_sess_cmds(struct se_session *se_sess)
2370 {
2371         struct se_cmd *se_cmd, *tmp_cmd;
2372         unsigned long flags;
2373
2374         list_for_each_entry_safe(se_cmd, tmp_cmd,
2375                                 &se_sess->sess_wait_list, se_cmd_list) {
2376                 list_del(&se_cmd->se_cmd_list);
2377
2378                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2379                         " %d\n", se_cmd, se_cmd->t_state,
2380                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2381
2382                 wait_for_completion(&se_cmd->cmd_wait_comp);
2383                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2384                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2385                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2386
2387                 se_cmd->se_tfo->release_cmd(se_cmd);
2388         }
2389
2390         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2391         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2392         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2393
2394 }
2395 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2396
2397 /*      transport_lun_wait_for_tasks():
2398  *
2399  *      Called from ConfigFS context to stop the passed struct se_cmd to allow
2400  *      an struct se_lun to be successfully shutdown.
2401  */
2402 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
2403 {
2404         unsigned long flags;
2405         int ret = 0;
2406
2407         /*
2408          * If the frontend has already requested this struct se_cmd to
2409          * be stopped, we can safely ignore this struct se_cmd.
2410          */
2411         spin_lock_irqsave(&cmd->t_state_lock, flags);
2412         if (cmd->transport_state & CMD_T_STOP) {
2413                 cmd->transport_state &= ~CMD_T_LUN_STOP;
2414
2415                 pr_debug("ConfigFS ITT[0x%08x] - CMD_T_STOP, skipping\n",
2416                          cmd->se_tfo->get_task_tag(cmd));
2417                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2418                 transport_cmd_check_stop(cmd, false, false);
2419                 return -EPERM;
2420         }
2421         cmd->transport_state |= CMD_T_LUN_FE_STOP;
2422         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2423
2424         // XXX: audit task_flags checks.
2425         spin_lock_irqsave(&cmd->t_state_lock, flags);
2426         if ((cmd->transport_state & CMD_T_BUSY) &&
2427             (cmd->transport_state & CMD_T_SENT)) {
2428                 if (!target_stop_cmd(cmd, &flags))
2429                         ret++;
2430         }
2431         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2432
2433         pr_debug("ConfigFS: cmd: %p stop tasks ret:"
2434                         " %d\n", cmd, ret);
2435         if (!ret) {
2436                 pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
2437                                 cmd->se_tfo->get_task_tag(cmd));
2438                 wait_for_completion(&cmd->transport_lun_stop_comp);
2439                 pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
2440                                 cmd->se_tfo->get_task_tag(cmd));
2441         }
2442
2443         return 0;
2444 }
2445
2446 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
2447 {
2448         struct se_cmd *cmd = NULL;
2449         unsigned long lun_flags, cmd_flags;
2450         /*
2451          * Do exception processing and return CHECK_CONDITION status to the
2452          * Initiator Port.
2453          */
2454         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2455         while (!list_empty(&lun->lun_cmd_list)) {
2456                 cmd = list_first_entry(&lun->lun_cmd_list,
2457                        struct se_cmd, se_lun_node);
2458                 list_del_init(&cmd->se_lun_node);
2459
2460                 spin_lock(&cmd->t_state_lock);
2461                 pr_debug("SE_LUN[%d] - Setting cmd->transport"
2462                         "_lun_stop for  ITT: 0x%08x\n",
2463                         cmd->se_lun->unpacked_lun,
2464                         cmd->se_tfo->get_task_tag(cmd));
2465                 cmd->transport_state |= CMD_T_LUN_STOP;
2466                 spin_unlock(&cmd->t_state_lock);
2467
2468                 spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2469
2470                 if (!cmd->se_lun) {
2471                         pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
2472                                 cmd->se_tfo->get_task_tag(cmd),
2473                                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2474                         BUG();
2475                 }
2476                 /*
2477                  * If the Storage engine still owns the iscsi_cmd_t, determine
2478                  * and/or stop its context.
2479                  */
2480                 pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
2481                         "_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
2482                         cmd->se_tfo->get_task_tag(cmd));
2483
2484                 if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
2485                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2486                         continue;
2487                 }
2488
2489                 pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
2490                         "_wait_for_tasks(): SUCCESS\n",
2491                         cmd->se_lun->unpacked_lun,
2492                         cmd->se_tfo->get_task_tag(cmd));
2493
2494                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2495                 if (!(cmd->transport_state & CMD_T_DEV_ACTIVE)) {
2496                         spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2497                         goto check_cond;
2498                 }
2499                 cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
2500                 target_remove_from_state_list(cmd);
2501                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2502
2503                 /*
2504                  * The Storage engine stopped this struct se_cmd before it was
2505                  * send to the fabric frontend for delivery back to the
2506                  * Initiator Node.  Return this SCSI CDB back with an
2507                  * CHECK_CONDITION status.
2508                  */
2509 check_cond:
2510                 transport_send_check_condition_and_sense(cmd,
2511                                 TCM_NON_EXISTENT_LUN, 0);
2512                 /*
2513                  *  If the fabric frontend is waiting for this iscsi_cmd_t to
2514                  * be released, notify the waiting thread now that LU has
2515                  * finished accessing it.
2516                  */
2517                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2518                 if (cmd->transport_state & CMD_T_LUN_FE_STOP) {
2519                         pr_debug("SE_LUN[%d] - Detected FE stop for"
2520                                 " struct se_cmd: %p ITT: 0x%08x\n",
2521                                 lun->unpacked_lun,
2522                                 cmd, cmd->se_tfo->get_task_tag(cmd));
2523
2524                         spin_unlock_irqrestore(&cmd->t_state_lock,
2525                                         cmd_flags);
2526                         transport_cmd_check_stop(cmd, false, false);
2527                         complete(&cmd->transport_lun_fe_stop_comp);
2528                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2529                         continue;
2530                 }
2531                 pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
2532                         lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
2533
2534                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2535                 spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2536         }
2537         spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2538 }
2539
2540 static int transport_clear_lun_thread(void *p)
2541 {
2542         struct se_lun *lun = p;
2543
2544         __transport_clear_lun_from_sessions(lun);
2545         complete(&lun->lun_shutdown_comp);
2546
2547         return 0;
2548 }
2549
2550 int transport_clear_lun_from_sessions(struct se_lun *lun)
2551 {
2552         struct task_struct *kt;
2553
2554         kt = kthread_run(transport_clear_lun_thread, lun,
2555                         "tcm_cl_%u", lun->unpacked_lun);
2556         if (IS_ERR(kt)) {
2557                 pr_err("Unable to start clear_lun thread\n");
2558                 return PTR_ERR(kt);
2559         }
2560         wait_for_completion(&lun->lun_shutdown_comp);
2561
2562         return 0;
2563 }
2564
2565 /**
2566  * transport_wait_for_tasks - wait for completion to occur
2567  * @cmd:        command to wait
2568  *
2569  * Called from frontend fabric context to wait for storage engine
2570  * to pause and/or release frontend generated struct se_cmd.
2571  */
2572 bool transport_wait_for_tasks(struct se_cmd *cmd)
2573 {
2574         unsigned long flags;
2575
2576         spin_lock_irqsave(&cmd->t_state_lock, flags);
2577         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2578             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2579                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2580                 return false;
2581         }
2582
2583         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2584             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2585                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2586                 return false;
2587         }
2588         /*
2589          * If we are already stopped due to an external event (ie: LUN shutdown)
2590          * sleep until the connection can have the passed struct se_cmd back.
2591          * The cmd->transport_lun_stopped_sem will be upped by
2592          * transport_clear_lun_from_sessions() once the ConfigFS context caller
2593          * has completed its operation on the struct se_cmd.
2594          */
2595         if (cmd->transport_state & CMD_T_LUN_STOP) {
2596                 pr_debug("wait_for_tasks: Stopping"
2597                         " wait_for_completion(&cmd->t_tasktransport_lun_fe"
2598                         "_stop_comp); for ITT: 0x%08x\n",
2599                         cmd->se_tfo->get_task_tag(cmd));
2600                 /*
2601                  * There is a special case for WRITES where a FE exception +
2602                  * LUN shutdown means ConfigFS context is still sleeping on
2603                  * transport_lun_stop_comp in transport_lun_wait_for_tasks().
2604                  * We go ahead and up transport_lun_stop_comp just to be sure
2605                  * here.
2606                  */
2607                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2608                 complete(&cmd->transport_lun_stop_comp);
2609                 wait_for_completion(&cmd->transport_lun_fe_stop_comp);
2610                 spin_lock_irqsave(&cmd->t_state_lock, flags);
2611
2612                 target_remove_from_state_list(cmd);
2613                 /*
2614                  * At this point, the frontend who was the originator of this
2615                  * struct se_cmd, now owns the structure and can be released through
2616                  * normal means below.
2617                  */
2618                 pr_debug("wait_for_tasks: Stopped"
2619                         " wait_for_completion(&cmd->t_tasktransport_lun_fe_"
2620                         "stop_comp); for ITT: 0x%08x\n",
2621                         cmd->se_tfo->get_task_tag(cmd));
2622
2623                 cmd->transport_state &= ~CMD_T_LUN_STOP;
2624         }
2625
2626         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2627                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2628                 return false;
2629         }
2630
2631         cmd->transport_state |= CMD_T_STOP;
2632
2633         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2634                 " i_state: %d, t_state: %d, CMD_T_STOP\n",
2635                 cmd, cmd->se_tfo->get_task_tag(cmd),
2636                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2637
2638         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2639
2640         wait_for_completion(&cmd->t_transport_stop_comp);
2641
2642         spin_lock_irqsave(&cmd->t_state_lock, flags);
2643         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2644
2645         pr_debug("wait_for_tasks: Stopped wait_for_completion("
2646                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2647                 cmd->se_tfo->get_task_tag(cmd));
2648
2649         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2650
2651         return true;
2652 }
2653 EXPORT_SYMBOL(transport_wait_for_tasks);
2654
2655 static int transport_get_sense_codes(
2656         struct se_cmd *cmd,
2657         u8 *asc,
2658         u8 *ascq)
2659 {
2660         *asc = cmd->scsi_asc;
2661         *ascq = cmd->scsi_ascq;
2662
2663         return 0;
2664 }
2665
2666 int
2667 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2668                 sense_reason_t reason, int from_transport)
2669 {
2670         unsigned char *buffer = cmd->sense_buffer;
2671         unsigned long flags;
2672         u8 asc = 0, ascq = 0;
2673
2674         spin_lock_irqsave(&cmd->t_state_lock, flags);
2675         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2676                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2677                 return 0;
2678         }
2679         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2680         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2681
2682         if (!reason && from_transport)
2683                 goto after_reason;
2684
2685         if (!from_transport)
2686                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2687
2688         /*
2689          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2690          * SENSE KEY values from include/scsi/scsi.h
2691          */
2692         switch (reason) {
2693         case TCM_NO_SENSE:
2694                 /* CURRENT ERROR */
2695                 buffer[0] = 0x70;
2696                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2697                 /* Not Ready */
2698                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2699                 /* NO ADDITIONAL SENSE INFORMATION */
2700                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2701                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2702                 break;
2703         case TCM_NON_EXISTENT_LUN:
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 UNIT NOT SUPPORTED */
2710                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2711                 break;
2712         case TCM_UNSUPPORTED_SCSI_OPCODE:
2713         case TCM_SECTOR_COUNT_TOO_MANY:
2714                 /* CURRENT ERROR */
2715                 buffer[0] = 0x70;
2716                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2717                 /* ILLEGAL REQUEST */
2718                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2719                 /* INVALID COMMAND OPERATION CODE */
2720                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2721                 break;
2722         case TCM_UNKNOWN_MODE_PAGE:
2723                 /* CURRENT ERROR */
2724                 buffer[0] = 0x70;
2725                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2726                 /* ILLEGAL REQUEST */
2727                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2728                 /* INVALID FIELD IN CDB */
2729                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2730                 break;
2731         case TCM_CHECK_CONDITION_ABORT_CMD:
2732                 /* CURRENT ERROR */
2733                 buffer[0] = 0x70;
2734                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2735                 /* ABORTED COMMAND */
2736                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2737                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2738                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2739                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2740                 break;
2741         case TCM_INCORRECT_AMOUNT_OF_DATA:
2742                 /* CURRENT ERROR */
2743                 buffer[0] = 0x70;
2744                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2745                 /* ABORTED COMMAND */
2746                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2747                 /* WRITE ERROR */
2748                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2749                 /* NOT ENOUGH UNSOLICITED DATA */
2750                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2751                 break;
2752         case TCM_INVALID_CDB_FIELD:
2753                 /* CURRENT ERROR */
2754                 buffer[0] = 0x70;
2755                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2756                 /* ILLEGAL REQUEST */
2757                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2758                 /* INVALID FIELD IN CDB */
2759                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2760                 break;
2761         case TCM_INVALID_PARAMETER_LIST:
2762                 /* CURRENT ERROR */
2763                 buffer[0] = 0x70;
2764                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2765                 /* ILLEGAL REQUEST */
2766                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2767                 /* INVALID FIELD IN PARAMETER LIST */
2768                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2769                 break;
2770         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2771                 /* CURRENT ERROR */
2772                 buffer[0] = 0x70;
2773                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2774                 /* ILLEGAL REQUEST */
2775                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2776                 /* PARAMETER LIST LENGTH ERROR */
2777                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2778                 break;
2779         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2780                 /* CURRENT ERROR */
2781                 buffer[0] = 0x70;
2782                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2783                 /* ABORTED COMMAND */
2784                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2785                 /* WRITE ERROR */
2786                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2787                 /* UNEXPECTED_UNSOLICITED_DATA */
2788                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2789                 break;
2790         case TCM_SERVICE_CRC_ERROR:
2791                 /* CURRENT ERROR */
2792                 buffer[0] = 0x70;
2793                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2794                 /* ABORTED COMMAND */
2795                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2796                 /* PROTOCOL SERVICE CRC ERROR */
2797                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2798                 /* N/A */
2799                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2800                 break;
2801         case TCM_SNACK_REJECTED:
2802                 /* CURRENT ERROR */
2803                 buffer[0] = 0x70;
2804                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2805                 /* ABORTED COMMAND */
2806                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2807                 /* READ ERROR */
2808                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2809                 /* FAILED RETRANSMISSION REQUEST */
2810                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2811                 break;
2812         case TCM_WRITE_PROTECTED:
2813                 /* CURRENT ERROR */
2814                 buffer[0] = 0x70;
2815                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2816                 /* DATA PROTECT */
2817                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2818                 /* WRITE PROTECTED */
2819                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2820                 break;
2821         case TCM_ADDRESS_OUT_OF_RANGE:
2822                 /* CURRENT ERROR */
2823                 buffer[0] = 0x70;
2824                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2825                 /* ILLEGAL REQUEST */
2826                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2827                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2828                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2829                 break;
2830         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2831                 /* CURRENT ERROR */
2832                 buffer[0] = 0x70;
2833                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2834                 /* UNIT ATTENTION */
2835                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2836                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2837                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2838                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2839                 break;
2840         case TCM_CHECK_CONDITION_NOT_READY:
2841                 /* CURRENT ERROR */
2842                 buffer[0] = 0x70;
2843                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2844                 /* Not Ready */
2845                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2846                 transport_get_sense_codes(cmd, &asc, &ascq);
2847                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2848                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2849                 break;
2850         case TCM_MISCOMPARE_VERIFY:
2851                 /* CURRENT ERROR */
2852                 buffer[0] = 0x70;
2853                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2854                 buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
2855                 /* MISCOMPARE DURING VERIFY OPERATION */
2856                 buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
2857                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
2858                 break;
2859         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2860         default:
2861                 /* CURRENT ERROR */
2862                 buffer[0] = 0x70;
2863                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2864                 /*
2865                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2866                  * Solaris initiators.  Returning NOT READY instead means the
2867                  * operations will be retried a finite number of times and we
2868                  * can survive intermittent errors.
2869                  */
2870                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2871                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2872                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2873                 break;
2874         }
2875         /*
2876          * This code uses linux/include/scsi/scsi.h SAM status codes!
2877          */
2878         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2879         /*
2880          * Automatically padded, this value is encoded in the fabric's
2881          * data_length response PDU containing the SCSI defined sense data.
2882          */
2883         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2884
2885 after_reason:
2886         trace_target_cmd_complete(cmd);
2887         return cmd->se_tfo->queue_status(cmd);
2888 }
2889 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2890
2891 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2892 {
2893         if (!(cmd->transport_state & CMD_T_ABORTED))
2894                 return 0;
2895
2896         if (!send_status || (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
2897                 return 1;
2898
2899         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2900                  cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2901
2902         cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
2903         trace_target_cmd_complete(cmd);
2904         cmd->se_tfo->queue_status(cmd);
2905
2906         return 1;
2907 }
2908 EXPORT_SYMBOL(transport_check_aborted_status);
2909
2910 void transport_send_task_abort(struct se_cmd *cmd)
2911 {
2912         unsigned long flags;
2913
2914         spin_lock_irqsave(&cmd->t_state_lock, flags);
2915         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION | SCF_SENT_DELAYED_TAS)) {
2916                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2917                 return;
2918         }
2919         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2920
2921         /*
2922          * If there are still expected incoming fabric WRITEs, we wait
2923          * until until they have completed before sending a TASK_ABORTED
2924          * response.  This response with TASK_ABORTED status will be
2925          * queued back to fabric module by transport_check_aborted_status().
2926          */
2927         if (cmd->data_direction == DMA_TO_DEVICE) {
2928                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2929                         cmd->transport_state |= CMD_T_ABORTED;
2930                         smp_mb__after_atomic_inc();
2931                 }
2932         }
2933         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2934
2935         transport_lun_remove_cmd(cmd);
2936
2937         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2938                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
2939                 cmd->se_tfo->get_task_tag(cmd));
2940
2941         trace_target_cmd_complete(cmd);
2942         cmd->se_tfo->queue_status(cmd);
2943 }
2944
2945 static void target_tmr_work(struct work_struct *work)
2946 {
2947         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2948         struct se_device *dev = cmd->se_dev;
2949         struct se_tmr_req *tmr = cmd->se_tmr_req;
2950         int ret;
2951
2952         switch (tmr->function) {
2953         case TMR_ABORT_TASK:
2954                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2955                 break;
2956         case TMR_ABORT_TASK_SET:
2957         case TMR_CLEAR_ACA:
2958         case TMR_CLEAR_TASK_SET:
2959                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2960                 break;
2961         case TMR_LUN_RESET:
2962                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2963                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2964                                          TMR_FUNCTION_REJECTED;
2965                 break;
2966         case TMR_TARGET_WARM_RESET:
2967                 tmr->response = TMR_FUNCTION_REJECTED;
2968                 break;
2969         case TMR_TARGET_COLD_RESET:
2970                 tmr->response = TMR_FUNCTION_REJECTED;
2971                 break;
2972         default:
2973                 pr_err("Uknown TMR function: 0x%02x.\n",
2974                                 tmr->function);
2975                 tmr->response = TMR_FUNCTION_REJECTED;
2976                 break;
2977         }
2978
2979         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2980         cmd->se_tfo->queue_tm_rsp(cmd);
2981
2982         transport_cmd_check_stop_to_fabric(cmd);
2983 }
2984
2985 int transport_generic_handle_tmr(
2986         struct se_cmd *cmd)
2987 {
2988         INIT_WORK(&cmd->work, target_tmr_work);
2989         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2990         return 0;
2991 }
2992 EXPORT_SYMBOL(transport_generic_handle_tmr);