drivers/target/target_core_transport.c

   1 /*******************************************************************************
   2  * Filename:  target_core_transport.c
   3  *
   4  * This file contains the Generic Target Engine Core.
   5  *
   6  * (c) Copyright 2002-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/net.h>
  27 #include <linux/delay.h>
  28 #include <linux/string.h>
  29 #include <linux/timer.h>
  30 #include <linux/slab.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/kthread.h>
  33 #include <linux/in.h>
  34 #include <linux/cdrom.h>
  35 #include <linux/module.h>
  36 #include <linux/ratelimit.h>
  37 #include <asm/unaligned.h>
  38 #include <net/sock.h>
  39 #include <net/tcp.h>
  40 #include <scsi/scsi.h>
  41 #include <scsi/scsi_cmnd.h>
  42 #include <scsi/scsi_tcq.h>
  43
  44 #include <target/target_core_base.h>
  45 #include <target/target_core_backend.h>
  46 #include <target/target_core_fabric.h>
  47 #include <target/target_core_configfs.h>
  48
  49 #include "target_core_internal.h"
  50 #include "target_core_alua.h"
  51 #include "target_core_pr.h"
  52 #include "target_core_ua.h"
  53
  54 #define CREATE_TRACE_POINTS
  55 #include <trace/events/target.h>
  56
  57 static struct workqueue_struct *target_completion_wq;
  58 static struct kmem_cache *se_sess_cache;
  59 struct kmem_cache *se_ua_cache;
  60 struct kmem_cache *t10_pr_reg_cache;
  61 struct kmem_cache *t10_alua_lu_gp_cache;
  62 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  63 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  64 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
  65 struct kmem_cache *t10_alua_lba_map_cache;
  66 struct kmem_cache *t10_alua_lba_map_mem_cache;
  67
  68 static void transport_complete_task_attr(struct se_cmd *cmd);
  69 static void transport_handle_queue_full(struct se_cmd *cmd,
  70                 struct se_device *dev);
  71 static int transport_put_cmd(struct se_cmd *cmd);
  72 static void target_complete_ok_work(struct work_struct *work);
  73
  74 int init_se_kmem_caches(void)
  75 {
  76         se_sess_cache = kmem_cache_create("se_sess_cache",
  77                         sizeof(struct se_session), __alignof__(struct se_session),
  78                         0, NULL);
  79         if (!se_sess_cache) {
  80                 pr_err("kmem_cache_create() for struct se_session"
  81                                 " failed\n");
  82                 goto out;
  83         }
  84         se_ua_cache = kmem_cache_create("se_ua_cache",
  85                         sizeof(struct se_ua), __alignof__(struct se_ua),
  86                         0, NULL);
  87         if (!se_ua_cache) {
  88                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  89                 goto out_free_sess_cache;
  90         }
  91         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  92                         sizeof(struct t10_pr_registration),
  93                         __alignof__(struct t10_pr_registration), 0, NULL);
  94         if (!t10_pr_reg_cache) {
  95                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  96                                 " failed\n");
  97                 goto out_free_ua_cache;
  98         }
  99         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
 100                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
 101                         0, NULL);
 102         if (!t10_alua_lu_gp_cache) {
 103                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 104                                 " failed\n");
 105                 goto out_free_pr_reg_cache;
 106         }
 107         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 108                         sizeof(struct t10_alua_lu_gp_member),
 109                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 110         if (!t10_alua_lu_gp_mem_cache) {
 111                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 112                                 "cache failed\n");
 113                 goto out_free_lu_gp_cache;
 114         }
 115         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 116                         sizeof(struct t10_alua_tg_pt_gp),
 117                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 118         if (!t10_alua_tg_pt_gp_cache) {
 119                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 120                                 "cache failed\n");
 121                 goto out_free_lu_gp_mem_cache;
 122         }
 123         t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
 124                         "t10_alua_tg_pt_gp_mem_cache",
 125                         sizeof(struct t10_alua_tg_pt_gp_member),
 126                         __alignof__(struct t10_alua_tg_pt_gp_member),
 127                         0, NULL);
 128         if (!t10_alua_tg_pt_gp_mem_cache) {
 129                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 130                                 "mem_t failed\n");
 131                 goto out_free_tg_pt_gp_cache;
 132         }
 133         t10_alua_lba_map_cache = kmem_cache_create(
 134                         "t10_alua_lba_map_cache",
 135                         sizeof(struct t10_alua_lba_map),
 136                         __alignof__(struct t10_alua_lba_map), 0, NULL);
 137         if (!t10_alua_lba_map_cache) {
 138                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
 139                                 "cache failed\n");
 140                 goto out_free_tg_pt_gp_mem_cache;
 141         }
 142         t10_alua_lba_map_mem_cache = kmem_cache_create(
 143                         "t10_alua_lba_map_mem_cache",
 144                         sizeof(struct t10_alua_lba_map_member),
 145                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
 146         if (!t10_alua_lba_map_mem_cache) {
 147                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
 148                                 "cache failed\n");
 149                 goto out_free_lba_map_cache;
 150         }
 151
 152         target_completion_wq = alloc_workqueue("target_completion",
 153                                                WQ_MEM_RECLAIM, 0);
 154         if (!target_completion_wq)
 155                 goto out_free_lba_map_mem_cache;
 156
 157         return 0;
 158
 159 out_free_lba_map_mem_cache:
 160         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 161 out_free_lba_map_cache:
 162         kmem_cache_destroy(t10_alua_lba_map_cache);
 163 out_free_tg_pt_gp_mem_cache:
 164         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 165 out_free_tg_pt_gp_cache:
 166         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 167 out_free_lu_gp_mem_cache:
 168         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 169 out_free_lu_gp_cache:
 170         kmem_cache_destroy(t10_alua_lu_gp_cache);
 171 out_free_pr_reg_cache:
 172         kmem_cache_destroy(t10_pr_reg_cache);
 173 out_free_ua_cache:
 174         kmem_cache_destroy(se_ua_cache);
 175 out_free_sess_cache:
 176         kmem_cache_destroy(se_sess_cache);
 177 out:
 178         return -ENOMEM;
 179 }
 180
 181 void release_se_kmem_caches(void)
 182 {
 183         destroy_workqueue(target_completion_wq);
 184         kmem_cache_destroy(se_sess_cache);
 185         kmem_cache_destroy(se_ua_cache);
 186         kmem_cache_destroy(t10_pr_reg_cache);
 187         kmem_cache_destroy(t10_alua_lu_gp_cache);
 188         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 189         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 190         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 191         kmem_cache_destroy(t10_alua_lba_map_cache);
 192         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 193 }
 194
 195 /* This code ensures unique mib indexes are handed out. */
 196 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 197 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 198
 199 /*
 200  * Allocate a new row index for the entry type specified
 201  */
 202 u32 scsi_get_new_index(scsi_index_t type)
 203 {
 204         u32 new_index;
 205
 206         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 207
 208         spin_lock(&scsi_mib_index_lock);
 209         new_index = ++scsi_mib_index[type];
 210         spin_unlock(&scsi_mib_index_lock);
 211
 212         return new_index;
 213 }
 214
 215 void transport_subsystem_check_init(void)
 216 {
 217         int ret;
 218         static int sub_api_initialized;
 219
 220         if (sub_api_initialized)
 221                 return;
 222
 223         ret = request_module("target_core_iblock");
 224         if (ret != 0)
 225                 pr_err("Unable to load target_core_iblock\n");
 226
 227         ret = request_module("target_core_file");
 228         if (ret != 0)
 229                 pr_err("Unable to load target_core_file\n");
 230
 231         ret = request_module("target_core_pscsi");
 232         if (ret != 0)
 233                 pr_err("Unable to load target_core_pscsi\n");
 234
 235         sub_api_initialized = 1;
 236 }
 237
 238 struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
 239 {
 240         struct se_session *se_sess;
 241
 242         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 243         if (!se_sess) {
 244                 pr_err("Unable to allocate struct se_session from"
 245                                 " se_sess_cache\n");
 246                 return ERR_PTR(-ENOMEM);
 247         }
 248         INIT_LIST_HEAD(&se_sess->sess_list);
 249         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 250         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 251         INIT_LIST_HEAD(&se_sess->sess_wait_list);
 252         spin_lock_init(&se_sess->sess_cmd_lock);
 253         kref_init(&se_sess->sess_kref);
 254         se_sess->sup_prot_ops = sup_prot_ops;
 255
 256         return se_sess;
 257 }
 258 EXPORT_SYMBOL(transport_init_session);
 259
 260 int transport_alloc_session_tags(struct se_session *se_sess,
 261                                  unsigned int tag_num, unsigned int tag_size)
 262 {
 263         int rc;
 264
 265         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
 266                                         GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
 267         if (!se_sess->sess_cmd_map) {
 268                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
 269                 if (!se_sess->sess_cmd_map) {
 270                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 271                         return -ENOMEM;
 272                 }
 273         }
 274
 275         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
 276         if (rc < 0) {
 277                 pr_err("Unable to init se_sess->sess_tag_pool,"
 278                         " tag_num: %u\n", tag_num);
 279                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 280                         vfree(se_sess->sess_cmd_map);
 281                 else
 282                         kfree(se_sess->sess_cmd_map);
 283                 se_sess->sess_cmd_map = NULL;
 284                 return -ENOMEM;
 285         }
 286
 287         return 0;
 288 }
 289 EXPORT_SYMBOL(transport_alloc_session_tags);
 290
 291 struct se_session *transport_init_session_tags(unsigned int tag_num,
 292                                                unsigned int tag_size,
 293                                                enum target_prot_op sup_prot_ops)
 294 {
 295         struct se_session *se_sess;
 296         int rc;
 297
 298         se_sess = transport_init_session(sup_prot_ops);
 299         if (IS_ERR(se_sess))
 300                 return se_sess;
 301
 302         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 303         if (rc < 0) {
 304                 transport_free_session(se_sess);
 305                 return ERR_PTR(-ENOMEM);
 306         }
 307
 308         return se_sess;
 309 }
 310 EXPORT_SYMBOL(transport_init_session_tags);
 311
 312 /*
 313  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 314  */
 315 void __transport_register_session(
 316         struct se_portal_group *se_tpg,
 317         struct se_node_acl *se_nacl,
 318         struct se_session *se_sess,
 319         void *fabric_sess_ptr)
 320 {
 321         unsigned char buf[PR_REG_ISID_LEN];
 322
 323         se_sess->se_tpg = se_tpg;
 324         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 325         /*
 326          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 327          *
 328          * Only set for struct se_session's that will actually be moving I/O.
 329          * eg: *NOT* discovery sessions.
 330          */
 331         if (se_nacl) {
 332                 /*
 333                  * If the fabric module supports an ISID based TransportID,
 334                  * save this value in binary from the fabric I_T Nexus now.
 335                  */
 336                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 337                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 338                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 339                                         &buf[0], PR_REG_ISID_LEN);
 340                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 341                 }
 342                 kref_get(&se_nacl->acl_kref);
 343
 344                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 345                 /*
 346                  * The se_nacl->nacl_sess pointer will be set to the
 347                  * last active I_T Nexus for each struct se_node_acl.
 348                  */
 349                 se_nacl->nacl_sess = se_sess;
 350
 351                 list_add_tail(&se_sess->sess_acl_list,
 352                               &se_nacl->acl_sess_list);
 353                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 354         }
 355         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 356
 357         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 358                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 359 }
 360 EXPORT_SYMBOL(__transport_register_session);
 361
 362 void transport_register_session(
 363         struct se_portal_group *se_tpg,
 364         struct se_node_acl *se_nacl,
 365         struct se_session *se_sess,
 366         void *fabric_sess_ptr)
 367 {
 368         unsigned long flags;
 369
 370         spin_lock_irqsave(&se_tpg->session_lock, flags);
 371         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 372         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 373 }
 374 EXPORT_SYMBOL(transport_register_session);
 375
 376 static void target_release_session(struct kref *kref)
 377 {
 378         struct se_session *se_sess = container_of(kref,
 379                         struct se_session, sess_kref);
 380         struct se_portal_group *se_tpg = se_sess->se_tpg;
 381
 382         se_tpg->se_tpg_tfo->close_session(se_sess);
 383 }
 384
 385 void target_get_session(struct se_session *se_sess)
 386 {
 387         kref_get(&se_sess->sess_kref);
 388 }
 389 EXPORT_SYMBOL(target_get_session);
 390
 391 void target_put_session(struct se_session *se_sess)
 392 {
 393         struct se_portal_group *tpg = se_sess->se_tpg;
 394
 395         if (tpg->se_tpg_tfo->put_session != NULL) {
 396                 tpg->se_tpg_tfo->put_session(se_sess);
 397                 return;
 398         }
 399         kref_put(&se_sess->sess_kref, target_release_session);
 400 }
 401 EXPORT_SYMBOL(target_put_session);
 402
 403 static void target_complete_nacl(struct kref *kref)
 404 {
 405         struct se_node_acl *nacl = container_of(kref,
 406                                 struct se_node_acl, acl_kref);
 407
 408         complete(&nacl->acl_free_comp);
 409 }
 410
 411 void target_put_nacl(struct se_node_acl *nacl)
 412 {
 413         kref_put(&nacl->acl_kref, target_complete_nacl);
 414 }
 415
 416 void transport_deregister_session_configfs(struct se_session *se_sess)
 417 {
 418         struct se_node_acl *se_nacl;
 419         unsigned long flags;
 420         /*
 421          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 422          */
 423         se_nacl = se_sess->se_node_acl;
 424         if (se_nacl) {
 425                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 426                 if (se_nacl->acl_stop == 0)
 427                         list_del(&se_sess->sess_acl_list);
 428                 /*
 429                  * If the session list is empty, then clear the pointer.
 430                  * Otherwise, set the struct se_session pointer from the tail
 431                  * element of the per struct se_node_acl active session list.
 432                  */
 433                 if (list_empty(&se_nacl->acl_sess_list))
 434                         se_nacl->nacl_sess = NULL;
 435                 else {
 436                         se_nacl->nacl_sess = container_of(
 437                                         se_nacl->acl_sess_list.prev,
 438                                         struct se_session, sess_acl_list);
 439                 }
 440                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 441         }
 442 }
 443 EXPORT_SYMBOL(transport_deregister_session_configfs);
 444
 445 void transport_free_session(struct se_session *se_sess)
 446 {
 447         if (se_sess->sess_cmd_map) {
 448                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 449                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 450                         vfree(se_sess->sess_cmd_map);
 451                 else
 452                         kfree(se_sess->sess_cmd_map);
 453         }
 454         kmem_cache_free(se_sess_cache, se_sess);
 455 }
 456 EXPORT_SYMBOL(transport_free_session);
 457
 458 void transport_deregister_session(struct se_session *se_sess)
 459 {
 460         struct se_portal_group *se_tpg = se_sess->se_tpg;
 461         struct target_core_fabric_ops *se_tfo;
 462         struct se_node_acl *se_nacl;
 463         unsigned long flags;
 464         bool comp_nacl = true;
 465
 466         if (!se_tpg) {
 467                 transport_free_session(se_sess);
 468                 return;
 469         }
 470         se_tfo = se_tpg->se_tpg_tfo;
 471
 472         spin_lock_irqsave(&se_tpg->session_lock, flags);
 473         list_del(&se_sess->sess_list);
 474         se_sess->se_tpg = NULL;
 475         se_sess->fabric_sess_ptr = NULL;
 476         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 477
 478         /*
 479          * Determine if we need to do extra work for this initiator node's
 480          * struct se_node_acl if it had been previously dynamically generated.
 481          */
 482         se_nacl = se_sess->se_node_acl;
 483
 484         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 485         if (se_nacl && se_nacl->dynamic_node_acl) {
 486                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 487                         list_del(&se_nacl->acl_list);
 488                         se_tpg->num_node_acls--;
 489                         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 490                         core_tpg_wait_for_nacl_pr_ref(se_nacl);
 491                         core_free_device_list_for_node(se_nacl, se_tpg);
 492                         se_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
 493
 494                         comp_nacl = false;
 495                         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 496                 }
 497         }
 498         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 499
 500         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 501                 se_tpg->se_tpg_tfo->get_fabric_name());
 502         /*
 503          * If last kref is dropping now for an explicit NodeACL, awake sleeping
 504          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 505          * removal context.
 506          */
 507         if (se_nacl && comp_nacl == true)
 508                 target_put_nacl(se_nacl);
 509
 510         transport_free_session(se_sess);
 511 }
 512 EXPORT_SYMBOL(transport_deregister_session);
 513
 514 /*
 515  * Called with cmd->t_state_lock held.
 516  */
 517 static void target_remove_from_state_list(struct se_cmd *cmd)
 518 {
 519         struct se_device *dev = cmd->se_dev;
 520         unsigned long flags;
 521
 522         if (!dev)
 523                 return;
 524
 525         if (cmd->transport_state & CMD_T_BUSY)
 526                 return;
 527
 528         spin_lock_irqsave(&dev->execute_task_lock, flags);
 529         if (cmd->state_active) {
 530                 list_del(&cmd->state_list);
 531                 cmd->state_active = false;
 532         }
 533         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 534 }
 535
 536 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 537                                     bool write_pending)
 538 {
 539         unsigned long flags;
 540
 541         spin_lock_irqsave(&cmd->t_state_lock, flags);
 542         if (write_pending)
 543                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 544
 545         if (remove_from_lists) {
 546                 target_remove_from_state_list(cmd);
 547
 548                 /*
 549                  * Clear struct se_cmd->se_lun before the handoff to FE.
 550                  */
 551                 cmd->se_lun = NULL;
 552         }
 553
 554         /*
 555          * Determine if frontend context caller is requesting the stopping of
 556          * this command for frontend exceptions.
 557          */
 558         if (cmd->transport_state & CMD_T_STOP) {
 559                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
 560                         __func__, __LINE__,
 561                         cmd->se_tfo->get_task_tag(cmd));
 562
 563                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 564
 565                 complete(&cmd->t_transport_stop_comp);
 566                 return 1;
 567         }
 568
 569         cmd->transport_state &= ~CMD_T_ACTIVE;
 570         if (remove_from_lists) {
 571                 /*
 572                  * Some fabric modules like tcm_loop can release
 573                  * their internally allocated I/O reference now and
 574                  * struct se_cmd now.
 575                  *
 576                  * Fabric modules are expected to return '1' here if the
 577                  * se_cmd being passed is released at this point,
 578                  * or zero if not being released.
 579                  */
 580                 if (cmd->se_tfo->check_stop_free != NULL) {
 581                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 582                         return cmd->se_tfo->check_stop_free(cmd);
 583                 }
 584         }
 585
 586         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 587         return 0;
 588 }
 589
 590 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 591 {
 592         return transport_cmd_check_stop(cmd, true, false);
 593 }
 594
 595 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 596 {
 597         struct se_lun *lun = cmd->se_lun;
 598
 599         if (!lun)
 600                 return;
 601
 602         if (cmpxchg(&cmd->lun_ref_active, true, false))
 603                 percpu_ref_put(&lun->lun_ref);
 604 }
 605
 606 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 607 {
 608         if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
 609                 transport_lun_remove_cmd(cmd);
 610         /*
 611          * Allow the fabric driver to unmap any resources before
 612          * releasing the descriptor via TFO->release_cmd()
 613          */
 614         if (remove)
 615                 cmd->se_tfo->aborted_task(cmd);
 616
 617         if (transport_cmd_check_stop_to_fabric(cmd))
 618                 return;
 619         if (remove)
 620                 transport_put_cmd(cmd);
 621 }
 622
 623 static void target_complete_failure_work(struct work_struct *work)
 624 {
 625         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 626
 627         transport_generic_request_failure(cmd,
 628                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 629 }
 630
 631 /*
 632  * Used when asking transport to copy Sense Data from the underlying
 633  * Linux/SCSI struct scsi_cmnd
 634  */
 635 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 636 {
 637         struct se_device *dev = cmd->se_dev;
 638
 639         WARN_ON(!cmd->se_lun);
 640
 641         if (!dev)
 642                 return NULL;
 643
 644         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 645                 return NULL;
 646
 647         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 648
 649         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 650                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 651         return cmd->sense_buffer;
 652 }
 653
 654 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 655 {
 656         struct se_device *dev = cmd->se_dev;
 657         int success = scsi_status == GOOD;
 658         unsigned long flags;
 659
 660         cmd->scsi_status = scsi_status;
 661
 662
 663         spin_lock_irqsave(&cmd->t_state_lock, flags);
 664         cmd->transport_state &= ~CMD_T_BUSY;
 665
 666         if (dev && dev->transport->transport_complete) {
 667                 dev->transport->transport_complete(cmd,
 668                                 cmd->t_data_sg,
 669                                 transport_get_sense_buffer(cmd));
 670                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 671                         success = 1;
 672         }
 673
 674         /*
 675          * See if we are waiting to complete for an exception condition.
 676          */
 677         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
 678                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 679                 complete(&cmd->task_stop_comp);
 680                 return;
 681         }
 682
 683         /*
 684          * Check for case where an explicit ABORT_TASK has been received
 685          * and transport_wait_for_tasks() will be waiting for completion..
 686          */
 687         if (cmd->transport_state & CMD_T_ABORTED &&
 688             cmd->transport_state & CMD_T_STOP) {
 689                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 690                 complete(&cmd->t_transport_stop_comp);
 691                 return;
 692         } else if (!success) {
 693                 INIT_WORK(&cmd->work, target_complete_failure_work);
 694         } else {
 695                 INIT_WORK(&cmd->work, target_complete_ok_work);
 696         }
 697
 698         cmd->t_state = TRANSPORT_COMPLETE;
 699         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 700         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 701
 702         queue_work(target_completion_wq, &cmd->work);
 703 }
 704 EXPORT_SYMBOL(target_complete_cmd);
 705
 706 static void target_add_to_state_list(struct se_cmd *cmd)
 707 {
 708         struct se_device *dev = cmd->se_dev;
 709         unsigned long flags;
 710
 711         spin_lock_irqsave(&dev->execute_task_lock, flags);
 712         if (!cmd->state_active) {
 713                 list_add_tail(&cmd->state_list, &dev->state_list);
 714                 cmd->state_active = true;
 715         }
 716         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 717 }
 718
 719 /*
 720  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 721  */
 722 static void transport_write_pending_qf(struct se_cmd *cmd);
 723 static void transport_complete_qf(struct se_cmd *cmd);
 724
 725 void target_qf_do_work(struct work_struct *work)
 726 {
 727         struct se_device *dev = container_of(work, struct se_device,
 728                                         qf_work_queue);
 729         LIST_HEAD(qf_cmd_list);
 730         struct se_cmd *cmd, *cmd_tmp;
 731
 732         spin_lock_irq(&dev->qf_cmd_lock);
 733         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 734         spin_unlock_irq(&dev->qf_cmd_lock);
 735
 736         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 737                 list_del(&cmd->se_qf_node);
 738                 atomic_dec(&dev->dev_qf_count);
 739                 smp_mb__after_atomic();
 740
 741                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 742                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 743                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 744                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 745                         : "UNKNOWN");
 746
 747                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 748                         transport_write_pending_qf(cmd);
 749                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 750                         transport_complete_qf(cmd);
 751         }
 752 }
 753
 754 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 755 {
 756         switch (cmd->data_direction) {
 757         case DMA_NONE:
 758                 return "NONE";
 759         case DMA_FROM_DEVICE:
 760                 return "READ";
 761         case DMA_TO_DEVICE:
 762                 return "WRITE";
 763         case DMA_BIDIRECTIONAL:
 764                 return "BIDI";
 765         default:
 766                 break;
 767         }
 768
 769         return "UNKNOWN";
 770 }
 771
 772 void transport_dump_dev_state(
 773         struct se_device *dev,
 774         char *b,
 775         int *bl)
 776 {
 777         *bl += sprintf(b + *bl, "Status: ");
 778         if (dev->export_count)
 779                 *bl += sprintf(b + *bl, "ACTIVATED");
 780         else
 781                 *bl += sprintf(b + *bl, "DEACTIVATED");
 782
 783         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 784         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 785                 dev->dev_attrib.block_size,
 786                 dev->dev_attrib.hw_max_sectors);
 787         *bl += sprintf(b + *bl, "        ");
 788 }
 789
 790 void transport_dump_vpd_proto_id(
 791         struct t10_vpd *vpd,
 792         unsigned char *p_buf,
 793         int p_buf_len)
 794 {
 795         unsigned char buf[VPD_TMP_BUF_SIZE];
 796         int len;
 797
 798         memset(buf, 0, VPD_TMP_BUF_SIZE);
 799         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 800
 801         switch (vpd->protocol_identifier) {
 802         case 0x00:
 803                 sprintf(buf+len, "Fibre Channel\n");
 804                 break;
 805         case 0x10:
 806                 sprintf(buf+len, "Parallel SCSI\n");
 807                 break;
 808         case 0x20:
 809                 sprintf(buf+len, "SSA\n");
 810                 break;
 811         case 0x30:
 812                 sprintf(buf+len, "IEEE 1394\n");
 813                 break;
 814         case 0x40:
 815                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 816                                 " Protocol\n");
 817                 break;
 818         case 0x50:
 819                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 820                 break;
 821         case 0x60:
 822                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 823                 break;
 824         case 0x70:
 825                 sprintf(buf+len, "Automation/Drive Interface Transport"
 826                                 " Protocol\n");
 827                 break;
 828         case 0x80:
 829                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 830                 break;
 831         default:
 832                 sprintf(buf+len, "Unknown 0x%02x\n",
 833                                 vpd->protocol_identifier);
 834                 break;
 835         }
 836
 837         if (p_buf)
 838                 strncpy(p_buf, buf, p_buf_len);
 839         else
 840                 pr_debug("%s", buf);
 841 }
 842
 843 void
 844 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 845 {
 846         /*
 847          * Check if the Protocol Identifier Valid (PIV) bit is set..
 848          *
 849          * from spc3r23.pdf section 7.5.1
 850          */
 851          if (page_83[1] & 0x80) {
 852                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 853                 vpd->protocol_identifier_set = 1;
 854                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 855         }
 856 }
 857 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 858
 859 int transport_dump_vpd_assoc(
 860         struct t10_vpd *vpd,
 861         unsigned char *p_buf,
 862         int p_buf_len)
 863 {
 864         unsigned char buf[VPD_TMP_BUF_SIZE];
 865         int ret = 0;
 866         int len;
 867
 868         memset(buf, 0, VPD_TMP_BUF_SIZE);
 869         len = sprintf(buf, "T10 VPD Identifier Association: ");
 870
 871         switch (vpd->association) {
 872         case 0x00:
 873                 sprintf(buf+len, "addressed logical unit\n");
 874                 break;
 875         case 0x10:
 876                 sprintf(buf+len, "target port\n");
 877                 break;
 878         case 0x20:
 879                 sprintf(buf+len, "SCSI target device\n");
 880                 break;
 881         default:
 882                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 883                 ret = -EINVAL;
 884                 break;
 885         }
 886
 887         if (p_buf)
 888                 strncpy(p_buf, buf, p_buf_len);
 889         else
 890                 pr_debug("%s", buf);
 891
 892         return ret;
 893 }
 894
 895 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 896 {
 897         /*
 898          * The VPD identification association..
 899          *
 900          * from spc3r23.pdf Section 7.6.3.1 Table 297
 901          */
 902         vpd->association = (page_83[1] & 0x30);
 903         return transport_dump_vpd_assoc(vpd, NULL, 0);
 904 }
 905 EXPORT_SYMBOL(transport_set_vpd_assoc);
 906
 907 int transport_dump_vpd_ident_type(
 908         struct t10_vpd *vpd,
 909         unsigned char *p_buf,
 910         int p_buf_len)
 911 {
 912         unsigned char buf[VPD_TMP_BUF_SIZE];
 913         int ret = 0;
 914         int len;
 915
 916         memset(buf, 0, VPD_TMP_BUF_SIZE);
 917         len = sprintf(buf, "T10 VPD Identifier Type: ");
 918
 919         switch (vpd->device_identifier_type) {
 920         case 0x00:
 921                 sprintf(buf+len, "Vendor specific\n");
 922                 break;
 923         case 0x01:
 924                 sprintf(buf+len, "T10 Vendor ID based\n");
 925                 break;
 926         case 0x02:
 927                 sprintf(buf+len, "EUI-64 based\n");
 928                 break;
 929         case 0x03:
 930                 sprintf(buf+len, "NAA\n");
 931                 break;
 932         case 0x04:
 933                 sprintf(buf+len, "Relative target port identifier\n");
 934                 break;
 935         case 0x08:
 936                 sprintf(buf+len, "SCSI name string\n");
 937                 break;
 938         default:
 939                 sprintf(buf+len, "Unsupported: 0x%02x\n",
 940                                 vpd->device_identifier_type);
 941                 ret = -EINVAL;
 942                 break;
 943         }
 944
 945         if (p_buf) {
 946                 if (p_buf_len < strlen(buf)+1)
 947                         return -EINVAL;
 948                 strncpy(p_buf, buf, p_buf_len);
 949         } else {
 950                 pr_debug("%s", buf);
 951         }
 952
 953         return ret;
 954 }
 955
 956 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
 957 {
 958         /*
 959          * The VPD identifier type..
 960          *
 961          * from spc3r23.pdf Section 7.6.3.1 Table 298
 962          */
 963         vpd->device_identifier_type = (page_83[1] & 0x0f);
 964         return transport_dump_vpd_ident_type(vpd, NULL, 0);
 965 }
 966 EXPORT_SYMBOL(transport_set_vpd_ident_type);
 967
 968 int transport_dump_vpd_ident(
 969         struct t10_vpd *vpd,
 970         unsigned char *p_buf,
 971         int p_buf_len)
 972 {
 973         unsigned char buf[VPD_TMP_BUF_SIZE];
 974         int ret = 0;
 975
 976         memset(buf, 0, VPD_TMP_BUF_SIZE);
 977
 978         switch (vpd->device_identifier_code_set) {
 979         case 0x01: /* Binary */
 980                 snprintf(buf, sizeof(buf),
 981                         "T10 VPD Binary Device Identifier: %s\n",
 982                         &vpd->device_identifier[0]);
 983                 break;
 984         case 0x02: /* ASCII */
 985                 snprintf(buf, sizeof(buf),
 986                         "T10 VPD ASCII Device Identifier: %s\n",
 987                         &vpd->device_identifier[0]);
 988                 break;
 989         case 0x03: /* UTF-8 */
 990                 snprintf(buf, sizeof(buf),
 991                         "T10 VPD UTF-8 Device Identifier: %s\n",
 992                         &vpd->device_identifier[0]);
 993                 break;
 994         default:
 995                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
 996                         " 0x%02x", vpd->device_identifier_code_set);
 997                 ret = -EINVAL;
 998                 break;
 999         }
1000
1001         if (p_buf)
1002                 strncpy(p_buf, buf, p_buf_len);
1003         else
1004                 pr_debug("%s", buf);
1005
1006         return ret;
1007 }
1008
1009 int
1010 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1011 {
1012         static const char hex_str[] = "0123456789abcdef";
1013         int j = 0, i = 4; /* offset to start of the identifier */
1014
1015         /*
1016          * The VPD Code Set (encoding)
1017          *
1018          * from spc3r23.pdf Section 7.6.3.1 Table 296
1019          */
1020         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1021         switch (vpd->device_identifier_code_set) {
1022         case 0x01: /* Binary */
1023                 vpd->device_identifier[j++] =
1024                                 hex_str[vpd->device_identifier_type];
1025                 while (i < (4 + page_83[3])) {
1026                         vpd->device_identifier[j++] =
1027                                 hex_str[(page_83[i] & 0xf0) >> 4];
1028                         vpd->device_identifier[j++] =
1029                                 hex_str[page_83[i] & 0x0f];
1030                         i++;
1031                 }
1032                 break;
1033         case 0x02: /* ASCII */
1034         case 0x03: /* UTF-8 */
1035                 while (i < (4 + page_83[3]))
1036                         vpd->device_identifier[j++] = page_83[i++];
1037                 break;
1038         default:
1039                 break;
1040         }
1041
1042         return transport_dump_vpd_ident(vpd, NULL, 0);
1043 }
1044 EXPORT_SYMBOL(transport_set_vpd_ident);
1045
1046 sense_reason_t
1047 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1048 {
1049         struct se_device *dev = cmd->se_dev;
1050
1051         if (cmd->unknown_data_length) {
1052                 cmd->data_length = size;
1053         } else if (size != cmd->data_length) {
1054                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1055                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1056                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1057                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1058
1059                 if (cmd->data_direction == DMA_TO_DEVICE) {
1060                         pr_err("Rejecting underflow/overflow"
1061                                         " WRITE data\n");
1062                         return TCM_INVALID_CDB_FIELD;
1063                 }
1064                 /*
1065                  * Reject READ_* or WRITE_* with overflow/underflow for
1066                  * type SCF_SCSI_DATA_CDB.
1067                  */
1068                 if (dev->dev_attrib.block_size != 512)  {
1069                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1070                                 " CDB on non 512-byte sector setup subsystem"
1071                                 " plugin: %s\n", dev->transport->name);
1072                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1073                         return TCM_INVALID_CDB_FIELD;
1074                 }
1075                 /*
1076                  * For the overflow case keep the existing fabric provided
1077                  * ->data_length.  Otherwise for the underflow case, reset
1078                  * ->data_length to the smaller SCSI expected data transfer
1079                  * length.
1080                  */
1081                 if (size > cmd->data_length) {
1082                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1083                         cmd->residual_count = (size - cmd->data_length);
1084                 } else {
1085                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1086                         cmd->residual_count = (cmd->data_length - size);
1087                         cmd->data_length = size;
1088                 }
1089         }
1090
1091         return 0;
1092
1093 }
1094
1095 /*
1096  * Used by fabric modules containing a local struct se_cmd within their
1097  * fabric dependent per I/O descriptor.
1098  */
1099 void transport_init_se_cmd(
1100         struct se_cmd *cmd,
1101         struct target_core_fabric_ops *tfo,
1102         struct se_session *se_sess,
1103         u32 data_length,
1104         int data_direction,
1105         int task_attr,
1106         unsigned char *sense_buffer)
1107 {
1108         INIT_LIST_HEAD(&cmd->se_delayed_node);
1109         INIT_LIST_HEAD(&cmd->se_qf_node);
1110         INIT_LIST_HEAD(&cmd->se_cmd_list);
1111         INIT_LIST_HEAD(&cmd->state_list);
1112         init_completion(&cmd->t_transport_stop_comp);
1113         init_completion(&cmd->cmd_wait_comp);
1114         init_completion(&cmd->task_stop_comp);
1115         spin_lock_init(&cmd->t_state_lock);
1116         kref_init(&cmd->cmd_kref);
1117         cmd->transport_state = CMD_T_DEV_ACTIVE;
1118
1119         cmd->se_tfo = tfo;
1120         cmd->se_sess = se_sess;
1121         cmd->data_length = data_length;
1122         cmd->data_direction = data_direction;
1123         cmd->sam_task_attr = task_attr;
1124         cmd->sense_buffer = sense_buffer;
1125
1126         cmd->state_active = false;
1127 }
1128 EXPORT_SYMBOL(transport_init_se_cmd);
1129
1130 static sense_reason_t
1131 transport_check_alloc_task_attr(struct se_cmd *cmd)
1132 {
1133         struct se_device *dev = cmd->se_dev;
1134
1135         /*
1136          * Check if SAM Task Attribute emulation is enabled for this
1137          * struct se_device storage object
1138          */
1139         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1140                 return 0;
1141
1142         if (cmd->sam_task_attr == MSG_ACA_TAG) {
1143                 pr_debug("SAM Task Attribute ACA"
1144                         " emulation is not supported\n");
1145                 return TCM_INVALID_CDB_FIELD;
1146         }
1147         /*
1148          * Used to determine when ORDERED commands should go from
1149          * Dormant to Active status.
1150          */
1151         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1152         smp_mb__after_atomic();
1153         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1154                         cmd->se_ordered_id, cmd->sam_task_attr,
1155                         dev->transport->name);
1156         return 0;
1157 }
1158
1159 sense_reason_t
1160 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1161 {
1162         struct se_device *dev = cmd->se_dev;
1163         sense_reason_t ret;
1164
1165         /*
1166          * Ensure that the received CDB is less than the max (252 + 8) bytes
1167          * for VARIABLE_LENGTH_CMD
1168          */
1169         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1170                 pr_err("Received SCSI CDB with command_size: %d that"
1171                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1172                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1173                 return TCM_INVALID_CDB_FIELD;
1174         }
1175         /*
1176          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1177          * allocate the additional extended CDB buffer now..  Otherwise
1178          * setup the pointer from __t_task_cdb to t_task_cdb.
1179          */
1180         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1181                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1182                                                 GFP_KERNEL);
1183                 if (!cmd->t_task_cdb) {
1184                         pr_err("Unable to allocate cmd->t_task_cdb"
1185                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1186                                 scsi_command_size(cdb),
1187                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1188                         return TCM_OUT_OF_RESOURCES;
1189                 }
1190         } else
1191                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1192         /*
1193          * Copy the original CDB into cmd->
1194          */
1195         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1196
1197         trace_target_sequencer_start(cmd);
1198
1199         /*
1200          * Check for an existing UNIT ATTENTION condition
1201          */
1202         ret = target_scsi3_ua_check(cmd);
1203         if (ret)
1204                 return ret;
1205
1206         ret = target_alua_state_check(cmd);
1207         if (ret)
1208                 return ret;
1209
1210         ret = target_check_reservation(cmd);
1211         if (ret) {
1212                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1213                 return ret;
1214         }
1215
1216         ret = dev->transport->parse_cdb(cmd);
1217         if (ret)
1218                 return ret;
1219
1220         ret = transport_check_alloc_task_attr(cmd);
1221         if (ret)
1222                 return ret;
1223
1224         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1225
1226         spin_lock(&cmd->se_lun->lun_sep_lock);
1227         if (cmd->se_lun->lun_sep)
1228                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1229         spin_unlock(&cmd->se_lun->lun_sep_lock);
1230         return 0;
1231 }
1232 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1233
1234 /*
1235  * Used by fabric module frontends to queue tasks directly.
1236  * Many only be used from process context only
1237  */
1238 int transport_handle_cdb_direct(
1239         struct se_cmd *cmd)
1240 {
1241         sense_reason_t ret;
1242
1243         if (!cmd->se_lun) {
1244                 dump_stack();
1245                 pr_err("cmd->se_lun is NULL\n");
1246                 return -EINVAL;
1247         }
1248         if (in_interrupt()) {
1249                 dump_stack();
1250                 pr_err("transport_generic_handle_cdb cannot be called"
1251                                 " from interrupt context\n");
1252                 return -EINVAL;
1253         }
1254         /*
1255          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1256          * outstanding descriptors are handled correctly during shutdown via
1257          * transport_wait_for_tasks()
1258          *
1259          * Also, we don't take cmd->t_state_lock here as we only expect
1260          * this to be called for initial descriptor submission.
1261          */
1262         cmd->t_state = TRANSPORT_NEW_CMD;
1263         cmd->transport_state |= CMD_T_ACTIVE;
1264
1265         /*
1266          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1267          * so follow TRANSPORT_NEW_CMD processing thread context usage
1268          * and call transport_generic_request_failure() if necessary..
1269          */
1270         ret = transport_generic_new_cmd(cmd);
1271         if (ret)
1272                 transport_generic_request_failure(cmd, ret);
1273         return 0;
1274 }
1275 EXPORT_SYMBOL(transport_handle_cdb_direct);
1276
1277 sense_reason_t
1278 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1279                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1280 {
1281         if (!sgl || !sgl_count)
1282                 return 0;
1283
1284         /*
1285          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1286          * scatterlists already have been set to follow what the fabric
1287          * passes for the original expected data transfer length.
1288          */
1289         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1290                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1291                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1292                 return TCM_INVALID_CDB_FIELD;
1293         }
1294
1295         cmd->t_data_sg = sgl;
1296         cmd->t_data_nents = sgl_count;
1297
1298         if (sgl_bidi && sgl_bidi_count) {
1299                 cmd->t_bidi_data_sg = sgl_bidi;
1300                 cmd->t_bidi_data_nents = sgl_bidi_count;
1301         }
1302         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1303         return 0;
1304 }
1305
1306 /*
1307  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1308  *                       se_cmd + use pre-allocated SGL memory.
1309  *
1310  * @se_cmd: command descriptor to submit
1311  * @se_sess: associated se_sess for endpoint
1312  * @cdb: pointer to SCSI CDB
1313  * @sense: pointer to SCSI sense buffer
1314  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1315  * @data_length: fabric expected data transfer length
1316  * @task_addr: SAM task attribute
1317  * @data_dir: DMA data direction
1318  * @flags: flags for command submission from target_sc_flags_tables
1319  * @sgl: struct scatterlist memory for unidirectional mapping
1320  * @sgl_count: scatterlist count for unidirectional mapping
1321  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1322  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1323  * @sgl_prot: struct scatterlist memory protection information
1324  * @sgl_prot_count: scatterlist count for protection information
1325  *
1326  * Returns non zero to signal active I/O shutdown failure.  All other
1327  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1328  * but still return zero here.
1329  *
1330  * This may only be called from process context, and also currently
1331  * assumes internal allocation of fabric payload buffer by target-core.
1332  */
1333 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1334                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1335                 u32 data_length, int task_attr, int data_dir, int flags,
1336                 struct scatterlist *sgl, u32 sgl_count,
1337                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1338                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1339 {
1340         struct se_portal_group *se_tpg;
1341         sense_reason_t rc;
1342         int ret;
1343
1344         se_tpg = se_sess->se_tpg;
1345         BUG_ON(!se_tpg);
1346         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1347         BUG_ON(in_interrupt());
1348         /*
1349          * Initialize se_cmd for target operation.  From this point
1350          * exceptions are handled by sending exception status via
1351          * target_core_fabric_ops->queue_status() callback
1352          */
1353         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1354                                 data_length, data_dir, task_attr, sense);
1355         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1356                 se_cmd->unknown_data_length = 1;
1357         /*
1358          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1359          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1360          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1361          * kref_put() to happen during fabric packet acknowledgement.
1362          */
1363         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1364         if (ret)
1365                 return ret;
1366         /*
1367          * Signal bidirectional data payloads to target-core
1368          */
1369         if (flags & TARGET_SCF_BIDI_OP)
1370                 se_cmd->se_cmd_flags |= SCF_BIDI;
1371         /*
1372          * Locate se_lun pointer and attach it to struct se_cmd
1373          */
1374         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1375         if (rc) {
1376                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1377                 target_put_sess_cmd(se_sess, se_cmd);
1378                 return 0;
1379         }
1380
1381         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1382         if (rc != 0) {
1383                 transport_generic_request_failure(se_cmd, rc);
1384                 return 0;
1385         }
1386
1387         /*
1388          * Save pointers for SGLs containing protection information,
1389          * if present.
1390          */
1391         if (sgl_prot_count) {
1392                 se_cmd->t_prot_sg = sgl_prot;
1393                 se_cmd->t_prot_nents = sgl_prot_count;
1394         }
1395
1396         /*
1397          * When a non zero sgl_count has been passed perform SGL passthrough
1398          * mapping for pre-allocated fabric memory instead of having target
1399          * core perform an internal SGL allocation..
1400          */
1401         if (sgl_count != 0) {
1402                 BUG_ON(!sgl);
1403
1404                 /*
1405                  * A work-around for tcm_loop as some userspace code via
1406                  * scsi-generic do not memset their associated read buffers,
1407                  * so go ahead and do that here for type non-data CDBs.  Also
1408                  * note that this is currently guaranteed to be a single SGL
1409                  * for this case by target core in target_setup_cmd_from_cdb()
1410                  * -> transport_generic_cmd_sequencer().
1411                  */
1412                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1413                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1414                         unsigned char *buf = NULL;
1415
1416                         if (sgl)
1417                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1418
1419                         if (buf) {
1420                                 memset(buf, 0, sgl->length);
1421                                 kunmap(sg_page(sgl));
1422                         }
1423                 }
1424
1425                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1426                                 sgl_bidi, sgl_bidi_count);
1427                 if (rc != 0) {
1428                         transport_generic_request_failure(se_cmd, rc);
1429                         return 0;
1430                 }
1431         }
1432
1433         /*
1434          * Check if we need to delay processing because of ALUA
1435          * Active/NonOptimized primary access state..
1436          */
1437         core_alua_check_nonop_delay(se_cmd);
1438
1439         transport_handle_cdb_direct(se_cmd);
1440         return 0;
1441 }
1442 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1443
1444 /*
1445  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1446  *
1447  * @se_cmd: command descriptor to submit
1448  * @se_sess: associated se_sess for endpoint
1449  * @cdb: pointer to SCSI CDB
1450  * @sense: pointer to SCSI sense buffer
1451  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1452  * @data_length: fabric expected data transfer length
1453  * @task_addr: SAM task attribute
1454  * @data_dir: DMA data direction
1455  * @flags: flags for command submission from target_sc_flags_tables
1456  *
1457  * Returns non zero to signal active I/O shutdown failure.  All other
1458  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1459  * but still return zero here.
1460  *
1461  * This may only be called from process context, and also currently
1462  * assumes internal allocation of fabric payload buffer by target-core.
1463  *
1464  * It also assumes interal target core SGL memory allocation.
1465  */
1466 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1467                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1468                 u32 data_length, int task_attr, int data_dir, int flags)
1469 {
1470         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1471                         unpacked_lun, data_length, task_attr, data_dir,
1472                         flags, NULL, 0, NULL, 0, NULL, 0);
1473 }
1474 EXPORT_SYMBOL(target_submit_cmd);
1475
1476 static void target_complete_tmr_failure(struct work_struct *work)
1477 {
1478         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1479
1480         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1481         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1482
1483         transport_cmd_check_stop_to_fabric(se_cmd);
1484 }
1485
1486 /**
1487  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1488  *                     for TMR CDBs
1489  *
1490  * @se_cmd: command descriptor to submit
1491  * @se_sess: associated se_sess for endpoint
1492  * @sense: pointer to SCSI sense buffer
1493  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1494  * @fabric_context: fabric context for TMR req
1495  * @tm_type: Type of TM request
1496  * @gfp: gfp type for caller
1497  * @tag: referenced task tag for TMR_ABORT_TASK
1498  * @flags: submit cmd flags
1499  *
1500  * Callable from all contexts.
1501  **/
1502
1503 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1504                 unsigned char *sense, u32 unpacked_lun,
1505                 void *fabric_tmr_ptr, unsigned char tm_type,
1506                 gfp_t gfp, unsigned int tag, int flags)
1507 {
1508         struct se_portal_group *se_tpg;
1509         int ret;
1510
1511         se_tpg = se_sess->se_tpg;
1512         BUG_ON(!se_tpg);
1513
1514         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1515                               0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1516         /*
1517          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1518          * allocation failure.
1519          */
1520         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1521         if (ret < 0)
1522                 return -ENOMEM;
1523
1524         if (tm_type == TMR_ABORT_TASK)
1525                 se_cmd->se_tmr_req->ref_task_tag = tag;
1526
1527         /* See target_submit_cmd for commentary */
1528         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1529         if (ret) {
1530                 core_tmr_release_req(se_cmd->se_tmr_req);
1531                 return ret;
1532         }
1533
1534         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1535         if (ret) {
1536                 /*
1537                  * For callback during failure handling, push this work off
1538                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1539                  */
1540                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1541                 schedule_work(&se_cmd->work);
1542                 return 0;
1543         }
1544         transport_generic_handle_tmr(se_cmd);
1545         return 0;
1546 }
1547 EXPORT_SYMBOL(target_submit_tmr);
1548
1549 /*
1550  * If the cmd is active, request it to be stopped and sleep until it
1551  * has completed.
1552  */
1553 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1554 {
1555         bool was_active = false;
1556
1557         if (cmd->transport_state & CMD_T_BUSY) {
1558                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1559                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1560
1561                 pr_debug("cmd %p waiting to complete\n", cmd);
1562                 wait_for_completion(&cmd->task_stop_comp);
1563                 pr_debug("cmd %p stopped successfully\n", cmd);
1564
1565                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1566                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1567                 cmd->transport_state &= ~CMD_T_BUSY;
1568                 was_active = true;
1569         }
1570
1571         return was_active;
1572 }
1573
1574 /*
1575  * Handle SAM-esque emulation for generic transport request failures.
1576  */
1577 void transport_generic_request_failure(struct se_cmd *cmd,
1578                 sense_reason_t sense_reason)
1579 {
1580         int ret = 0;
1581
1582         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1583                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1584                 cmd->t_task_cdb[0]);
1585         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1586                 cmd->se_tfo->get_cmd_state(cmd),
1587                 cmd->t_state, sense_reason);
1588         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1589                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1590                 (cmd->transport_state & CMD_T_STOP) != 0,
1591                 (cmd->transport_state & CMD_T_SENT) != 0);
1592
1593         /*
1594          * For SAM Task Attribute emulation for failed struct se_cmd
1595          */
1596         transport_complete_task_attr(cmd);
1597         /*
1598          * Handle special case for COMPARE_AND_WRITE failure, where the
1599          * callback is expected to drop the per device ->caw_mutex.
1600          */
1601         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1602              cmd->transport_complete_callback)
1603                 cmd->transport_complete_callback(cmd);
1604
1605         switch (sense_reason) {
1606         case TCM_NON_EXISTENT_LUN:
1607         case TCM_UNSUPPORTED_SCSI_OPCODE:
1608         case TCM_INVALID_CDB_FIELD:
1609         case TCM_INVALID_PARAMETER_LIST:
1610         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1611         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1612         case TCM_UNKNOWN_MODE_PAGE:
1613         case TCM_WRITE_PROTECTED:
1614         case TCM_ADDRESS_OUT_OF_RANGE:
1615         case TCM_CHECK_CONDITION_ABORT_CMD:
1616         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1617         case TCM_CHECK_CONDITION_NOT_READY:
1618         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1619         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1620         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1621                 break;
1622         case TCM_OUT_OF_RESOURCES:
1623                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1624                 break;
1625         case TCM_RESERVATION_CONFLICT:
1626                 /*
1627                  * No SENSE Data payload for this case, set SCSI Status
1628                  * and queue the response to $FABRIC_MOD.
1629                  *
1630                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1631                  */
1632                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1633                 /*
1634                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1635                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1636                  * CONFLICT STATUS.
1637                  *
1638                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1639                  */
1640                 if (cmd->se_sess &&
1641                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1642                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1643                                 cmd->orig_fe_lun, 0x2C,
1644                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1645
1646                 trace_target_cmd_complete(cmd);
1647                 ret = cmd->se_tfo-> queue_status(cmd);
1648                 if (ret == -EAGAIN || ret == -ENOMEM)
1649                         goto queue_full;
1650                 goto check_stop;
1651         default:
1652                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1653                         cmd->t_task_cdb[0], sense_reason);
1654                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1655                 break;
1656         }
1657
1658         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1659         if (ret == -EAGAIN || ret == -ENOMEM)
1660                 goto queue_full;
1661
1662 check_stop:
1663         transport_lun_remove_cmd(cmd);
1664         if (!transport_cmd_check_stop_to_fabric(cmd))
1665                 ;
1666         return;
1667
1668 queue_full:
1669         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1670         transport_handle_queue_full(cmd, cmd->se_dev);
1671 }
1672 EXPORT_SYMBOL(transport_generic_request_failure);
1673
1674 void __target_execute_cmd(struct se_cmd *cmd)
1675 {
1676         sense_reason_t ret;
1677
1678         if (cmd->execute_cmd) {
1679                 ret = cmd->execute_cmd(cmd);
1680                 if (ret) {
1681                         spin_lock_irq(&cmd->t_state_lock);
1682                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1683                         spin_unlock_irq(&cmd->t_state_lock);
1684
1685                         transport_generic_request_failure(cmd, ret);
1686                 }
1687         }
1688 }
1689
1690 static bool target_handle_task_attr(struct se_cmd *cmd)
1691 {
1692         struct se_device *dev = cmd->se_dev;
1693
1694         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1695                 return false;
1696
1697         /*
1698          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1699          * to allow the passed struct se_cmd list of tasks to the front of the list.
1700          */
1701         switch (cmd->sam_task_attr) {
1702         case MSG_HEAD_TAG:
1703                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1704                          "se_ordered_id: %u\n",
1705                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1706                 return false;
1707         case MSG_ORDERED_TAG:
1708                 atomic_inc(&dev->dev_ordered_sync);
1709                 smp_mb__after_atomic();
1710
1711                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1712                          " se_ordered_id: %u\n",
1713                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1714
1715                 /*
1716                  * Execute an ORDERED command if no other older commands
1717                  * exist that need to be completed first.
1718                  */
1719                 if (!atomic_read(&dev->simple_cmds))
1720                         return false;
1721                 break;
1722         default:
1723                 /*
1724                  * For SIMPLE and UNTAGGED Task Attribute commands
1725                  */
1726                 atomic_inc(&dev->simple_cmds);
1727                 smp_mb__after_atomic();
1728                 break;
1729         }
1730
1731         if (atomic_read(&dev->dev_ordered_sync) == 0)
1732                 return false;
1733
1734         spin_lock(&dev->delayed_cmd_lock);
1735         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1736         spin_unlock(&dev->delayed_cmd_lock);
1737
1738         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1739                 " delayed CMD list, se_ordered_id: %u\n",
1740                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1741                 cmd->se_ordered_id);
1742         return true;
1743 }
1744
1745 void target_execute_cmd(struct se_cmd *cmd)
1746 {
1747         /*
1748          * If the received CDB has aleady been aborted stop processing it here.
1749          */
1750         if (transport_check_aborted_status(cmd, 1))
1751                 return;
1752
1753         /*
1754          * Determine if frontend context caller is requesting the stopping of
1755          * this command for frontend exceptions.
1756          */
1757         spin_lock_irq(&cmd->t_state_lock);
1758         if (cmd->transport_state & CMD_T_STOP) {
1759                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1760                         __func__, __LINE__,
1761                         cmd->se_tfo->get_task_tag(cmd));
1762
1763                 spin_unlock_irq(&cmd->t_state_lock);
1764                 complete(&cmd->t_transport_stop_comp);
1765                 return;
1766         }
1767
1768         cmd->t_state = TRANSPORT_PROCESSING;
1769         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1770         spin_unlock_irq(&cmd->t_state_lock);
1771         /*
1772          * Perform WRITE_INSERT of PI using software emulation when backend
1773          * device has PI enabled, if the transport has not already generated
1774          * PI using hardware WRITE_INSERT offload.
1775          */
1776         if (cmd->prot_op == TARGET_PROT_DOUT_INSERT) {
1777                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1778                         sbc_dif_generate(cmd);
1779         }
1780
1781         if (target_handle_task_attr(cmd)) {
1782                 spin_lock_irq(&cmd->t_state_lock);
1783                 cmd->transport_state &= ~CMD_T_BUSY|CMD_T_SENT;
1784                 spin_unlock_irq(&cmd->t_state_lock);
1785                 return;
1786         }
1787
1788         __target_execute_cmd(cmd);
1789 }
1790 EXPORT_SYMBOL(target_execute_cmd);
1791
1792 /*
1793  * Process all commands up to the last received ORDERED task attribute which
1794  * requires another blocking boundary
1795  */
1796 static void target_restart_delayed_cmds(struct se_device *dev)
1797 {
1798         for (;;) {
1799                 struct se_cmd *cmd;
1800
1801                 spin_lock(&dev->delayed_cmd_lock);
1802                 if (list_empty(&dev->delayed_cmd_list)) {
1803                         spin_unlock(&dev->delayed_cmd_lock);
1804                         break;
1805                 }
1806
1807                 cmd = list_entry(dev->delayed_cmd_list.next,
1808                                  struct se_cmd, se_delayed_node);
1809                 list_del(&cmd->se_delayed_node);
1810                 spin_unlock(&dev->delayed_cmd_lock);
1811
1812                 __target_execute_cmd(cmd);
1813
1814                 if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1815                         break;
1816         }
1817 }
1818
1819 /*
1820  * Called from I/O completion to determine which dormant/delayed
1821  * and ordered cmds need to have their tasks added to the execution queue.
1822  */
1823 static void transport_complete_task_attr(struct se_cmd *cmd)
1824 {
1825         struct se_device *dev = cmd->se_dev;
1826
1827         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1828                 return;
1829
1830         if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1831                 atomic_dec(&dev->simple_cmds);
1832                 smp_mb__after_atomic();
1833                 dev->dev_cur_ordered_id++;
1834                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1835                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1836                         cmd->se_ordered_id);
1837         } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1838                 dev->dev_cur_ordered_id++;
1839                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1840                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1841                         cmd->se_ordered_id);
1842         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1843                 atomic_dec(&dev->dev_ordered_sync);
1844                 smp_mb__after_atomic();
1845
1846                 dev->dev_cur_ordered_id++;
1847                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1848                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1849         }
1850
1851         target_restart_delayed_cmds(dev);
1852 }
1853
1854 static void transport_complete_qf(struct se_cmd *cmd)
1855 {
1856         int ret = 0;
1857
1858         transport_complete_task_attr(cmd);
1859
1860         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1861                 trace_target_cmd_complete(cmd);
1862                 ret = cmd->se_tfo->queue_status(cmd);
1863                 if (ret)
1864                         goto out;
1865         }
1866
1867         switch (cmd->data_direction) {
1868         case DMA_FROM_DEVICE:
1869                 trace_target_cmd_complete(cmd);
1870                 ret = cmd->se_tfo->queue_data_in(cmd);
1871                 break;
1872         case DMA_TO_DEVICE:
1873                 if (cmd->se_cmd_flags & SCF_BIDI) {
1874                         ret = cmd->se_tfo->queue_data_in(cmd);
1875                         if (ret < 0)
1876                                 break;
1877                 }
1878                 /* Fall through for DMA_TO_DEVICE */
1879         case DMA_NONE:
1880                 trace_target_cmd_complete(cmd);
1881                 ret = cmd->se_tfo->queue_status(cmd);
1882                 break;
1883         default:
1884                 break;
1885         }
1886
1887 out:
1888         if (ret < 0) {
1889                 transport_handle_queue_full(cmd, cmd->se_dev);
1890                 return;
1891         }
1892         transport_lun_remove_cmd(cmd);
1893         transport_cmd_check_stop_to_fabric(cmd);
1894 }
1895
1896 static void transport_handle_queue_full(
1897         struct se_cmd *cmd,
1898         struct se_device *dev)
1899 {
1900         spin_lock_irq(&dev->qf_cmd_lock);
1901         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1902         atomic_inc(&dev->dev_qf_count);
1903         smp_mb__after_atomic();
1904         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1905
1906         schedule_work(&cmd->se_dev->qf_work_queue);
1907 }
1908
1909 static bool target_check_read_strip(struct se_cmd *cmd)
1910 {
1911         sense_reason_t rc;
1912
1913         if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
1914                 rc = sbc_dif_read_strip(cmd);
1915                 if (rc) {
1916                         cmd->pi_err = rc;
1917                         return true;
1918                 }
1919         }
1920
1921         return false;
1922 }
1923
1924 static void target_complete_ok_work(struct work_struct *work)
1925 {
1926         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1927         int ret;
1928
1929         /*
1930          * Check if we need to move delayed/dormant tasks from cmds on the
1931          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1932          * Attribute.
1933          */
1934         transport_complete_task_attr(cmd);
1935
1936         /*
1937          * Check to schedule QUEUE_FULL work, or execute an existing
1938          * cmd->transport_qf_callback()
1939          */
1940         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1941                 schedule_work(&cmd->se_dev->qf_work_queue);
1942
1943         /*
1944          * Check if we need to send a sense buffer from
1945          * the struct se_cmd in question.
1946          */
1947         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1948                 WARN_ON(!cmd->scsi_status);
1949                 ret = transport_send_check_condition_and_sense(
1950                                         cmd, 0, 1);
1951                 if (ret == -EAGAIN || ret == -ENOMEM)
1952                         goto queue_full;
1953
1954                 transport_lun_remove_cmd(cmd);
1955                 transport_cmd_check_stop_to_fabric(cmd);
1956                 return;
1957         }
1958         /*
1959          * Check for a callback, used by amongst other things
1960          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
1961          */
1962         if (cmd->transport_complete_callback) {
1963                 sense_reason_t rc;
1964
1965                 rc = cmd->transport_complete_callback(cmd);
1966                 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
1967                         return;
1968                 } else if (rc) {
1969                         ret = transport_send_check_condition_and_sense(cmd,
1970                                                 rc, 0);
1971                         if (ret == -EAGAIN || ret == -ENOMEM)
1972                                 goto queue_full;
1973
1974                         transport_lun_remove_cmd(cmd);
1975                         transport_cmd_check_stop_to_fabric(cmd);
1976                         return;
1977                 }
1978         }
1979
1980         switch (cmd->data_direction) {
1981         case DMA_FROM_DEVICE:
1982                 spin_lock(&cmd->se_lun->lun_sep_lock);
1983                 if (cmd->se_lun->lun_sep) {
1984                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1985                                         cmd->data_length;
1986                 }
1987                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1988                 /*
1989                  * Perform READ_STRIP of PI using software emulation when
1990                  * backend had PI enabled, if the transport will not be
1991                  * performing hardware READ_STRIP offload.
1992                  */
1993                 if (cmd->prot_op == TARGET_PROT_DIN_STRIP &&
1994                     target_check_read_strip(cmd)) {
1995                         ret = transport_send_check_condition_and_sense(cmd,
1996                                                 cmd->pi_err, 0);
1997                         if (ret == -EAGAIN || ret == -ENOMEM)
1998                                 goto queue_full;
1999
2000                         transport_lun_remove_cmd(cmd);
2001                         transport_cmd_check_stop_to_fabric(cmd);
2002                         return;
2003                 }
2004
2005                 trace_target_cmd_complete(cmd);
2006                 ret = cmd->se_tfo->queue_data_in(cmd);
2007                 if (ret == -EAGAIN || ret == -ENOMEM)
2008                         goto queue_full;
2009                 break;
2010         case DMA_TO_DEVICE:
2011                 spin_lock(&cmd->se_lun->lun_sep_lock);
2012                 if (cmd->se_lun->lun_sep) {
2013                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
2014                                 cmd->data_length;
2015                 }
2016                 spin_unlock(&cmd->se_lun->lun_sep_lock);
2017                 /*
2018                  * Check if we need to send READ payload for BIDI-COMMAND
2019                  */
2020                 if (cmd->se_cmd_flags & SCF_BIDI) {
2021                         spin_lock(&cmd->se_lun->lun_sep_lock);
2022                         if (cmd->se_lun->lun_sep) {
2023                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
2024                                         cmd->data_length;
2025                         }
2026                         spin_unlock(&cmd->se_lun->lun_sep_lock);
2027                         ret = cmd->se_tfo->queue_data_in(cmd);
2028                         if (ret == -EAGAIN || ret == -ENOMEM)
2029                                 goto queue_full;
2030                         break;
2031                 }
2032                 /* Fall through for DMA_TO_DEVICE */
2033         case DMA_NONE:
2034                 trace_target_cmd_complete(cmd);
2035                 ret = cmd->se_tfo->queue_status(cmd);
2036                 if (ret == -EAGAIN || ret == -ENOMEM)
2037                         goto queue_full;
2038                 break;
2039         default:
2040                 break;
2041         }
2042
2043         transport_lun_remove_cmd(cmd);
2044         transport_cmd_check_stop_to_fabric(cmd);
2045         return;
2046
2047 queue_full:
2048         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2049                 " data_direction: %d\n", cmd, cmd->data_direction);
2050         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2051         transport_handle_queue_full(cmd, cmd->se_dev);
2052 }
2053
2054 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2055 {
2056         struct scatterlist *sg;
2057         int count;
2058
2059         for_each_sg(sgl, sg, nents, count)
2060                 __free_page(sg_page(sg));
2061
2062         kfree(sgl);
2063 }
2064
2065 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2066 {
2067         /*
2068          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2069          * emulation, and free + reset pointers if necessary..
2070          */
2071         if (!cmd->t_data_sg_orig)
2072                 return;
2073
2074         kfree(cmd->t_data_sg);
2075         cmd->t_data_sg = cmd->t_data_sg_orig;
2076         cmd->t_data_sg_orig = NULL;
2077         cmd->t_data_nents = cmd->t_data_nents_orig;
2078         cmd->t_data_nents_orig = 0;
2079 }
2080
2081 static inline void transport_free_pages(struct se_cmd *cmd)
2082 {
2083         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2084                 transport_reset_sgl_orig(cmd);
2085                 return;
2086         }
2087         transport_reset_sgl_orig(cmd);
2088
2089         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2090         cmd->t_data_sg = NULL;
2091         cmd->t_data_nents = 0;
2092
2093         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2094         cmd->t_bidi_data_sg = NULL;
2095         cmd->t_bidi_data_nents = 0;
2096
2097         transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2098         cmd->t_prot_sg = NULL;
2099         cmd->t_prot_nents = 0;
2100 }
2101
2102 /**
2103  * transport_release_cmd - free a command
2104  * @cmd:       command to free
2105  *
2106  * This routine unconditionally frees a command, and reference counting
2107  * or list removal must be done in the caller.
2108  */
2109 static int transport_release_cmd(struct se_cmd *cmd)
2110 {
2111         BUG_ON(!cmd->se_tfo);
2112
2113         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2114                 core_tmr_release_req(cmd->se_tmr_req);
2115         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2116                 kfree(cmd->t_task_cdb);
2117         /*
2118          * If this cmd has been setup with target_get_sess_cmd(), drop
2119          * the kref and call ->release_cmd() in kref callback.
2120          */
2121         return target_put_sess_cmd(cmd->se_sess, cmd);
2122 }
2123
2124 /**
2125  * transport_put_cmd - release a reference to a command
2126  * @cmd:       command to release
2127  *
2128  * This routine releases our reference to the command and frees it if possible.
2129  */
2130 static int transport_put_cmd(struct se_cmd *cmd)
2131 {
2132         transport_free_pages(cmd);
2133         return transport_release_cmd(cmd);
2134 }
2135
2136 void *transport_kmap_data_sg(struct se_cmd *cmd)
2137 {
2138         struct scatterlist *sg = cmd->t_data_sg;
2139         struct page **pages;
2140         int i;
2141
2142         /*
2143          * We need to take into account a possible offset here for fabrics like
2144          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2145          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2146          */
2147         if (!cmd->t_data_nents)
2148                 return NULL;
2149
2150         BUG_ON(!sg);
2151         if (cmd->t_data_nents == 1)
2152                 return kmap(sg_page(sg)) + sg->offset;
2153
2154         /* >1 page. use vmap */
2155         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2156         if (!pages)
2157                 return NULL;
2158
2159         /* convert sg[] to pages[] */
2160         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2161                 pages[i] = sg_page(sg);
2162         }
2163
2164         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2165         kfree(pages);
2166         if (!cmd->t_data_vmap)
2167                 return NULL;
2168
2169         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2170 }
2171 EXPORT_SYMBOL(transport_kmap_data_sg);
2172
2173 void transport_kunmap_data_sg(struct se_cmd *cmd)
2174 {
2175         if (!cmd->t_data_nents) {
2176                 return;
2177         } else if (cmd->t_data_nents == 1) {
2178                 kunmap(sg_page(cmd->t_data_sg));
2179                 return;
2180         }
2181
2182         vunmap(cmd->t_data_vmap);
2183         cmd->t_data_vmap = NULL;
2184 }
2185 EXPORT_SYMBOL(transport_kunmap_data_sg);
2186
2187 int
2188 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2189                  bool zero_page)
2190 {
2191         struct scatterlist *sg;
2192         struct page *page;
2193         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2194         unsigned int nent;
2195         int i = 0;
2196
2197         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2198         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2199         if (!sg)
2200                 return -ENOMEM;
2201
2202         sg_init_table(sg, nent);
2203
2204         while (length) {
2205                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2206                 page = alloc_page(GFP_KERNEL | zero_flag);
2207                 if (!page)
2208                         goto out;
2209
2210                 sg_set_page(&sg[i], page, page_len, 0);
2211                 length -= page_len;
2212                 i++;
2213         }
2214         *sgl = sg;
2215         *nents = nent;
2216         return 0;
2217
2218 out:
2219         while (i > 0) {
2220                 i--;
2221                 __free_page(sg_page(&sg[i]));
2222         }
2223         kfree(sg);
2224         return -ENOMEM;
2225 }
2226
2227 /*
2228  * Allocate any required resources to execute the command.  For writes we
2229  * might not have the payload yet, so notify the fabric via a call to
2230  * ->write_pending instead. Otherwise place it on the execution queue.
2231  */
2232 sense_reason_t
2233 transport_generic_new_cmd(struct se_cmd *cmd)
2234 {
2235         int ret = 0;
2236
2237         /*
2238          * Determine is the TCM fabric module has already allocated physical
2239          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2240          * beforehand.
2241          */
2242         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2243             cmd->data_length) {
2244                 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2245
2246                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2247                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2248                         u32 bidi_length;
2249
2250                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2251                                 bidi_length = cmd->t_task_nolb *
2252                                               cmd->se_dev->dev_attrib.block_size;
2253                         else
2254                                 bidi_length = cmd->data_length;
2255
2256                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2257                                                &cmd->t_bidi_data_nents,
2258                                                bidi_length, zero_flag);
2259                         if (ret < 0)
2260                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2261                 }
2262
2263                 if (cmd->prot_op != TARGET_PROT_NORMAL) {
2264                         ret = target_alloc_sgl(&cmd->t_prot_sg,
2265                                                &cmd->t_prot_nents,
2266                                                cmd->prot_length, true);
2267                         if (ret < 0)
2268                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2269                 }
2270
2271                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2272                                        cmd->data_length, zero_flag);
2273                 if (ret < 0)
2274                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2275         }
2276         /*
2277          * If this command is not a write we can execute it right here,
2278          * for write buffers we need to notify the fabric driver first
2279          * and let it call back once the write buffers are ready.
2280          */
2281         target_add_to_state_list(cmd);
2282         if (cmd->data_direction != DMA_TO_DEVICE) {
2283                 target_execute_cmd(cmd);
2284                 return 0;
2285         }
2286         transport_cmd_check_stop(cmd, false, true);
2287
2288         ret = cmd->se_tfo->write_pending(cmd);
2289         if (ret == -EAGAIN || ret == -ENOMEM)
2290                 goto queue_full;
2291
2292         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2293         WARN_ON(ret);
2294
2295         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2296
2297 queue_full:
2298         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2299         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2300         transport_handle_queue_full(cmd, cmd->se_dev);
2301         return 0;
2302 }
2303 EXPORT_SYMBOL(transport_generic_new_cmd);
2304
2305 static void transport_write_pending_qf(struct se_cmd *cmd)
2306 {
2307         int ret;
2308
2309         ret = cmd->se_tfo->write_pending(cmd);
2310         if (ret == -EAGAIN || ret == -ENOMEM) {
2311                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2312                          cmd);
2313                 transport_handle_queue_full(cmd, cmd->se_dev);
2314         }
2315 }
2316
2317 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2318 {
2319         unsigned long flags;
2320         int ret = 0;
2321
2322         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2323                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2324                          transport_wait_for_tasks(cmd);
2325
2326                 ret = transport_release_cmd(cmd);
2327         } else {
2328                 if (wait_for_tasks)
2329                         transport_wait_for_tasks(cmd);
2330                 /*
2331                  * Handle WRITE failure case where transport_generic_new_cmd()
2332                  * has already added se_cmd to state_list, but fabric has
2333                  * failed command before I/O submission.
2334                  */
2335                 if (cmd->state_active) {
2336                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2337                         target_remove_from_state_list(cmd);
2338                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2339                 }
2340
2341                 if (cmd->se_lun)
2342                         transport_lun_remove_cmd(cmd);
2343
2344                 ret = transport_put_cmd(cmd);
2345         }
2346         return ret;
2347 }
2348 EXPORT_SYMBOL(transport_generic_free_cmd);
2349
2350 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2351  * @se_sess:    session to reference
2352  * @se_cmd:     command descriptor to add
2353  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2354  */
2355 int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2356                                bool ack_kref)
2357 {
2358         unsigned long flags;
2359         int ret = 0;
2360
2361         /*
2362          * Add a second kref if the fabric caller is expecting to handle
2363          * fabric acknowledgement that requires two target_put_sess_cmd()
2364          * invocations before se_cmd descriptor release.
2365          */
2366         if (ack_kref == true) {
2367                 kref_get(&se_cmd->cmd_kref);
2368                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2369         }
2370
2371         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2372         if (se_sess->sess_tearing_down) {
2373                 ret = -ESHUTDOWN;
2374                 goto out;
2375         }
2376         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2377 out:
2378         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2379         return ret;
2380 }
2381 EXPORT_SYMBOL(target_get_sess_cmd);
2382
2383 static void target_release_cmd_kref(struct kref *kref)
2384 {
2385         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2386         struct se_session *se_sess = se_cmd->se_sess;
2387
2388         if (list_empty(&se_cmd->se_cmd_list)) {
2389                 spin_unlock(&se_sess->sess_cmd_lock);
2390                 se_cmd->se_tfo->release_cmd(se_cmd);
2391                 return;
2392         }
2393         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2394                 spin_unlock(&se_sess->sess_cmd_lock);
2395                 complete(&se_cmd->cmd_wait_comp);
2396                 return;
2397         }
2398         list_del(&se_cmd->se_cmd_list);
2399         spin_unlock(&se_sess->sess_cmd_lock);
2400
2401         se_cmd->se_tfo->release_cmd(se_cmd);
2402 }
2403
2404 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2405  * @se_sess:    session to reference
2406  * @se_cmd:     command descriptor to drop
2407  */
2408 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2409 {
2410         return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2411                         &se_sess->sess_cmd_lock);
2412 }
2413 EXPORT_SYMBOL(target_put_sess_cmd);
2414
2415 /* target_sess_cmd_list_set_waiting - Flag all commands in
2416  *         sess_cmd_list to complete cmd_wait_comp.  Set
2417  *         sess_tearing_down so no more commands are queued.
2418  * @se_sess:    session to flag
2419  */
2420 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2421 {
2422         struct se_cmd *se_cmd;
2423         unsigned long flags;
2424
2425         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2426         if (se_sess->sess_tearing_down) {
2427                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2428                 return;
2429         }
2430         se_sess->sess_tearing_down = 1;
2431         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2432
2433         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2434                 se_cmd->cmd_wait_set = 1;
2435
2436         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2437 }
2438 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2439
2440 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2441  * @se_sess:    session to wait for active I/O
2442  */
2443 void target_wait_for_sess_cmds(struct se_session *se_sess)
2444 {
2445         struct se_cmd *se_cmd, *tmp_cmd;
2446         unsigned long flags;
2447
2448         list_for_each_entry_safe(se_cmd, tmp_cmd,
2449                                 &se_sess->sess_wait_list, se_cmd_list) {
2450                 list_del(&se_cmd->se_cmd_list);
2451
2452                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2453                         " %d\n", se_cmd, se_cmd->t_state,
2454                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2455
2456                 wait_for_completion(&se_cmd->cmd_wait_comp);
2457                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2458                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2459                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2460
2461                 se_cmd->se_tfo->release_cmd(se_cmd);
2462         }
2463
2464         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2465         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2466         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2467
2468 }
2469 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2470
2471 static int transport_clear_lun_ref_thread(void *p)
2472 {
2473         struct se_lun *lun = p;
2474
2475         percpu_ref_kill(&lun->lun_ref);
2476
2477         wait_for_completion(&lun->lun_ref_comp);
2478         complete(&lun->lun_shutdown_comp);
2479
2480         return 0;
2481 }
2482
2483 int transport_clear_lun_ref(struct se_lun *lun)
2484 {
2485         struct task_struct *kt;
2486
2487         kt = kthread_run(transport_clear_lun_ref_thread, lun,
2488                         "tcm_cl_%u", lun->unpacked_lun);
2489         if (IS_ERR(kt)) {
2490                 pr_err("Unable to start clear_lun thread\n");
2491                 return PTR_ERR(kt);
2492         }
2493         wait_for_completion(&lun->lun_shutdown_comp);
2494
2495         return 0;
2496 }
2497
2498 /**
2499  * transport_wait_for_tasks - wait for completion to occur
2500  * @cmd:        command to wait
2501  *
2502  * Called from frontend fabric context to wait for storage engine
2503  * to pause and/or release frontend generated struct se_cmd.
2504  */
2505 bool transport_wait_for_tasks(struct se_cmd *cmd)
2506 {
2507         unsigned long flags;
2508
2509         spin_lock_irqsave(&cmd->t_state_lock, flags);
2510         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2511             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2512                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2513                 return false;
2514         }
2515
2516         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2517             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2518                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2519                 return false;
2520         }
2521
2522         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2523                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2524                 return false;
2525         }
2526
2527         cmd->transport_state |= CMD_T_STOP;
2528
2529         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2530                 " i_state: %d, t_state: %d, CMD_T_STOP\n",
2531                 cmd, cmd->se_tfo->get_task_tag(cmd),
2532                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2533
2534         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2535
2536         wait_for_completion(&cmd->t_transport_stop_comp);
2537
2538         spin_lock_irqsave(&cmd->t_state_lock, flags);
2539         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2540
2541         pr_debug("wait_for_tasks: Stopped wait_for_completion("
2542                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2543                 cmd->se_tfo->get_task_tag(cmd));
2544
2545         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2546
2547         return true;
2548 }
2549 EXPORT_SYMBOL(transport_wait_for_tasks);
2550
2551 static int transport_get_sense_codes(
2552         struct se_cmd *cmd,
2553         u8 *asc,
2554         u8 *ascq)
2555 {
2556         *asc = cmd->scsi_asc;
2557         *ascq = cmd->scsi_ascq;
2558
2559         return 0;
2560 }
2561
2562 static
2563 void transport_err_sector_info(unsigned char *buffer, sector_t bad_sector)
2564 {
2565         /* Place failed LBA in sense data information descriptor 0. */
2566         buffer[SPC_ADD_SENSE_LEN_OFFSET] = 0xc;
2567         buffer[SPC_DESC_TYPE_OFFSET] = 0; /* Information */
2568         buffer[SPC_ADDITIONAL_DESC_LEN_OFFSET] = 0xa;
2569         buffer[SPC_VALIDITY_OFFSET] = 0x80;
2570
2571         /* Descriptor Information: failing sector */
2572         put_unaligned_be64(bad_sector, &buffer[12]);
2573 }
2574
2575 int
2576 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2577                 sense_reason_t reason, int from_transport)
2578 {
2579         unsigned char *buffer = cmd->sense_buffer;
2580         unsigned long flags;
2581         u8 asc = 0, ascq = 0;
2582
2583         spin_lock_irqsave(&cmd->t_state_lock, flags);
2584         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2585                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2586                 return 0;
2587         }
2588         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2589         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2590
2591         if (!reason && from_transport)
2592                 goto after_reason;
2593
2594         if (!from_transport)
2595                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2596
2597         /*
2598          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2599          * SENSE KEY values from include/scsi/scsi.h
2600          */
2601         switch (reason) {
2602         case TCM_NO_SENSE:
2603                 /* CURRENT ERROR */
2604                 buffer[0] = 0x70;
2605                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2606                 /* Not Ready */
2607                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2608                 /* NO ADDITIONAL SENSE INFORMATION */
2609                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2610                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2611                 break;
2612         case TCM_NON_EXISTENT_LUN:
2613                 /* CURRENT ERROR */
2614                 buffer[0] = 0x70;
2615                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2616                 /* ILLEGAL REQUEST */
2617                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2618                 /* LOGICAL UNIT NOT SUPPORTED */
2619                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2620                 break;
2621         case TCM_UNSUPPORTED_SCSI_OPCODE:
2622         case TCM_SECTOR_COUNT_TOO_MANY:
2623                 /* CURRENT ERROR */
2624                 buffer[0] = 0x70;
2625                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2626                 /* ILLEGAL REQUEST */
2627                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2628                 /* INVALID COMMAND OPERATION CODE */
2629                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2630                 break;
2631         case TCM_UNKNOWN_MODE_PAGE:
2632                 /* CURRENT ERROR */
2633                 buffer[0] = 0x70;
2634                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2635                 /* ILLEGAL REQUEST */
2636                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2637                 /* INVALID FIELD IN CDB */
2638                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2639                 break;
2640         case TCM_CHECK_CONDITION_ABORT_CMD:
2641                 /* CURRENT ERROR */
2642                 buffer[0] = 0x70;
2643                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2644                 /* ABORTED COMMAND */
2645                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2646                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2647                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2648                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2649                 break;
2650         case TCM_INCORRECT_AMOUNT_OF_DATA:
2651                 /* CURRENT ERROR */
2652                 buffer[0] = 0x70;
2653                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2654                 /* ABORTED COMMAND */
2655                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2656                 /* WRITE ERROR */
2657                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2658                 /* NOT ENOUGH UNSOLICITED DATA */
2659                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2660                 break;
2661         case TCM_INVALID_CDB_FIELD:
2662                 /* CURRENT ERROR */
2663                 buffer[0] = 0x70;
2664                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2665                 /* ILLEGAL REQUEST */
2666                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2667                 /* INVALID FIELD IN CDB */
2668                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2669                 break;
2670         case TCM_INVALID_PARAMETER_LIST:
2671                 /* CURRENT ERROR */
2672                 buffer[0] = 0x70;
2673                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2674                 /* ILLEGAL REQUEST */
2675                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2676                 /* INVALID FIELD IN PARAMETER LIST */
2677                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2678                 break;
2679         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2680                 /* CURRENT ERROR */
2681                 buffer[0] = 0x70;
2682                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2683                 /* ILLEGAL REQUEST */
2684                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2685                 /* PARAMETER LIST LENGTH ERROR */
2686                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2687                 break;
2688         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2689                 /* CURRENT ERROR */
2690                 buffer[0] = 0x70;
2691                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2692                 /* ABORTED COMMAND */
2693                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2694                 /* WRITE ERROR */
2695                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2696                 /* UNEXPECTED_UNSOLICITED_DATA */
2697                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2698                 break;
2699         case TCM_SERVICE_CRC_ERROR:
2700                 /* CURRENT ERROR */
2701                 buffer[0] = 0x70;
2702                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2703                 /* ABORTED COMMAND */
2704                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2705                 /* PROTOCOL SERVICE CRC ERROR */
2706                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2707                 /* N/A */
2708                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2709                 break;
2710         case TCM_SNACK_REJECTED:
2711                 /* CURRENT ERROR */
2712                 buffer[0] = 0x70;
2713                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2714                 /* ABORTED COMMAND */
2715                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2716                 /* READ ERROR */
2717                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2718                 /* FAILED RETRANSMISSION REQUEST */
2719                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2720                 break;
2721         case TCM_WRITE_PROTECTED:
2722                 /* CURRENT ERROR */
2723                 buffer[0] = 0x70;
2724                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2725                 /* DATA PROTECT */
2726                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2727                 /* WRITE PROTECTED */
2728                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2729                 break;
2730         case TCM_ADDRESS_OUT_OF_RANGE:
2731                 /* CURRENT ERROR */
2732                 buffer[0] = 0x70;
2733                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2734                 /* ILLEGAL REQUEST */
2735                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2736                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2737                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2738                 break;
2739         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2740                 /* CURRENT ERROR */
2741                 buffer[0] = 0x70;
2742                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2743                 /* UNIT ATTENTION */
2744                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2745                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2746                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2747                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2748                 break;
2749         case TCM_CHECK_CONDITION_NOT_READY:
2750                 /* CURRENT ERROR */
2751                 buffer[0] = 0x70;
2752                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2753                 /* Not Ready */
2754                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2755                 transport_get_sense_codes(cmd, &asc, &ascq);
2756                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2757                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2758                 break;
2759         case TCM_MISCOMPARE_VERIFY:
2760                 /* CURRENT ERROR */
2761                 buffer[0] = 0x70;
2762                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2763                 buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
2764                 /* MISCOMPARE DURING VERIFY OPERATION */
2765                 buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
2766                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
2767                 break;
2768         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
2769                 /* CURRENT ERROR */
2770                 buffer[0] = 0x70;
2771                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2772                 /* ILLEGAL REQUEST */
2773                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2774                 /* LOGICAL BLOCK GUARD CHECK FAILED */
2775                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2776                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x01;
2777                 transport_err_sector_info(buffer, cmd->bad_sector);
2778                 break;
2779         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
2780                 /* CURRENT ERROR */
2781                 buffer[0] = 0x70;
2782                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2783                 /* ILLEGAL REQUEST */
2784                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2785                 /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2786                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2787                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x02;
2788                 transport_err_sector_info(buffer, cmd->bad_sector);
2789                 break;
2790         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
2791                 /* CURRENT ERROR */
2792                 buffer[0] = 0x70;
2793                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2794                 /* ILLEGAL REQUEST */
2795                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2796                 /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2797                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2798                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2799                 transport_err_sector_info(buffer, cmd->bad_sector);
2800                 break;
2801         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2802         default:
2803                 /* CURRENT ERROR */
2804                 buffer[0] = 0x70;
2805                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2806                 /*
2807                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2808                  * Solaris initiators.  Returning NOT READY instead means the
2809                  * operations will be retried a finite number of times and we
2810                  * can survive intermittent errors.
2811                  */
2812                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2813                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2814                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2815                 break;
2816         }
2817         /*
2818          * This code uses linux/include/scsi/scsi.h SAM status codes!
2819          */
2820         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2821         /*
2822          * Automatically padded, this value is encoded in the fabric's
2823          * data_length response PDU containing the SCSI defined sense data.
2824          */
2825         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2826
2827 after_reason:
2828         trace_target_cmd_complete(cmd);
2829         return cmd->se_tfo->queue_status(cmd);
2830 }
2831 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2832
2833 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2834 {
2835         if (!(cmd->transport_state & CMD_T_ABORTED))
2836                 return 0;
2837
2838         /*
2839          * If cmd has been aborted but either no status is to be sent or it has
2840          * already been sent, just return
2841          */
2842         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
2843                 return 1;
2844
2845         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2846                  cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2847
2848         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2849         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2850         trace_target_cmd_complete(cmd);
2851         cmd->se_tfo->queue_status(cmd);
2852
2853         return 1;
2854 }
2855 EXPORT_SYMBOL(transport_check_aborted_status);
2856
2857 void transport_send_task_abort(struct se_cmd *cmd)
2858 {
2859         unsigned long flags;
2860
2861         spin_lock_irqsave(&cmd->t_state_lock, flags);
2862         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2863                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2864                 return;
2865         }
2866         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2867
2868         /*
2869          * If there are still expected incoming fabric WRITEs, we wait
2870          * until until they have completed before sending a TASK_ABORTED
2871          * response.  This response with TASK_ABORTED status will be
2872          * queued back to fabric module by transport_check_aborted_status().
2873          */
2874         if (cmd->data_direction == DMA_TO_DEVICE) {
2875                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2876                         cmd->transport_state |= CMD_T_ABORTED;
2877                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2878                         smp_mb__after_atomic();
2879                         return;
2880                 }
2881         }
2882         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2883
2884         transport_lun_remove_cmd(cmd);
2885
2886         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2887                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
2888                 cmd->se_tfo->get_task_tag(cmd));
2889
2890         trace_target_cmd_complete(cmd);
2891         cmd->se_tfo->queue_status(cmd);
2892 }
2893
2894 static void target_tmr_work(struct work_struct *work)
2895 {
2896         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2897         struct se_device *dev = cmd->se_dev;
2898         struct se_tmr_req *tmr = cmd->se_tmr_req;
2899         int ret;
2900
2901         switch (tmr->function) {
2902         case TMR_ABORT_TASK:
2903                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2904                 break;
2905         case TMR_ABORT_TASK_SET:
2906         case TMR_CLEAR_ACA:
2907         case TMR_CLEAR_TASK_SET:
2908                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2909                 break;
2910         case TMR_LUN_RESET:
2911                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2912                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2913                                          TMR_FUNCTION_REJECTED;
2914                 break;
2915         case TMR_TARGET_WARM_RESET:
2916                 tmr->response = TMR_FUNCTION_REJECTED;
2917                 break;
2918         case TMR_TARGET_COLD_RESET:
2919                 tmr->response = TMR_FUNCTION_REJECTED;
2920                 break;
2921         default:
2922                 pr_err("Uknown TMR function: 0x%02x.\n",
2923                                 tmr->function);
2924                 tmr->response = TMR_FUNCTION_REJECTED;
2925                 break;
2926         }
2927
2928         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2929         cmd->se_tfo->queue_tm_rsp(cmd);
2930
2931         transport_cmd_check_stop_to_fabric(cmd);
2932 }
2933
2934 int transport_generic_handle_tmr(
2935         struct se_cmd *cmd)
2936 {
2937         INIT_WORK(&cmd->work, target_tmr_work);
2938         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2939         return 0;
2940 }
2941 EXPORT_SYMBOL(transport_generic_handle_tmr);