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)
 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_all(&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_all(&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 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 707 {
 708         if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
 709                 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 710                         cmd->residual_count += cmd->data_length - length;
 711                 } else {
 712                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
 713                         cmd->residual_count = cmd->data_length - length;
 714                 }
 715
 716                 cmd->data_length = length;
 717         }
 718
 719         target_complete_cmd(cmd, scsi_status);
 720 }
 721 EXPORT_SYMBOL(target_complete_cmd_with_length);
 722
 723 static void target_add_to_state_list(struct se_cmd *cmd)
 724 {
 725         struct se_device *dev = cmd->se_dev;
 726         unsigned long flags;
 727
 728         spin_lock_irqsave(&dev->execute_task_lock, flags);
 729         if (!cmd->state_active) {
 730                 list_add_tail(&cmd->state_list, &dev->state_list);
 731                 cmd->state_active = true;
 732         }
 733         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 734 }
 735
 736 /*
 737  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 738  */
 739 static void transport_write_pending_qf(struct se_cmd *cmd);
 740 static void transport_complete_qf(struct se_cmd *cmd);
 741
 742 void target_qf_do_work(struct work_struct *work)
 743 {
 744         struct se_device *dev = container_of(work, struct se_device,
 745                                         qf_work_queue);
 746         LIST_HEAD(qf_cmd_list);
 747         struct se_cmd *cmd, *cmd_tmp;
 748
 749         spin_lock_irq(&dev->qf_cmd_lock);
 750         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 751         spin_unlock_irq(&dev->qf_cmd_lock);
 752
 753         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 754                 list_del(&cmd->se_qf_node);
 755                 atomic_dec_mb(&dev->dev_qf_count);
 756
 757                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 758                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 759                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 760                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 761                         : "UNKNOWN");
 762
 763                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 764                         transport_write_pending_qf(cmd);
 765                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 766                         transport_complete_qf(cmd);
 767         }
 768 }
 769
 770 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 771 {
 772         switch (cmd->data_direction) {
 773         case DMA_NONE:
 774                 return "NONE";
 775         case DMA_FROM_DEVICE:
 776                 return "READ";
 777         case DMA_TO_DEVICE:
 778                 return "WRITE";
 779         case DMA_BIDIRECTIONAL:
 780                 return "BIDI";
 781         default:
 782                 break;
 783         }
 784
 785         return "UNKNOWN";
 786 }
 787
 788 void transport_dump_dev_state(
 789         struct se_device *dev,
 790         char *b,
 791         int *bl)
 792 {
 793         *bl += sprintf(b + *bl, "Status: ");
 794         if (dev->export_count)
 795                 *bl += sprintf(b + *bl, "ACTIVATED");
 796         else
 797                 *bl += sprintf(b + *bl, "DEACTIVATED");
 798
 799         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 800         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 801                 dev->dev_attrib.block_size,
 802                 dev->dev_attrib.hw_max_sectors);
 803         *bl += sprintf(b + *bl, "        ");
 804 }
 805
 806 void transport_dump_vpd_proto_id(
 807         struct t10_vpd *vpd,
 808         unsigned char *p_buf,
 809         int p_buf_len)
 810 {
 811         unsigned char buf[VPD_TMP_BUF_SIZE];
 812         int len;
 813
 814         memset(buf, 0, VPD_TMP_BUF_SIZE);
 815         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 816
 817         switch (vpd->protocol_identifier) {
 818         case 0x00:
 819                 sprintf(buf+len, "Fibre Channel\n");
 820                 break;
 821         case 0x10:
 822                 sprintf(buf+len, "Parallel SCSI\n");
 823                 break;
 824         case 0x20:
 825                 sprintf(buf+len, "SSA\n");
 826                 break;
 827         case 0x30:
 828                 sprintf(buf+len, "IEEE 1394\n");
 829                 break;
 830         case 0x40:
 831                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 832                                 " Protocol\n");
 833                 break;
 834         case 0x50:
 835                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 836                 break;
 837         case 0x60:
 838                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 839                 break;
 840         case 0x70:
 841                 sprintf(buf+len, "Automation/Drive Interface Transport"
 842                                 " Protocol\n");
 843                 break;
 844         case 0x80:
 845                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 846                 break;
 847         default:
 848                 sprintf(buf+len, "Unknown 0x%02x\n",
 849                                 vpd->protocol_identifier);
 850                 break;
 851         }
 852
 853         if (p_buf)
 854                 strncpy(p_buf, buf, p_buf_len);
 855         else
 856                 pr_debug("%s", buf);
 857 }
 858
 859 void
 860 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 861 {
 862         /*
 863          * Check if the Protocol Identifier Valid (PIV) bit is set..
 864          *
 865          * from spc3r23.pdf section 7.5.1
 866          */
 867          if (page_83[1] & 0x80) {
 868                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 869                 vpd->protocol_identifier_set = 1;
 870                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 871         }
 872 }
 873 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 874
 875 int transport_dump_vpd_assoc(
 876         struct t10_vpd *vpd,
 877         unsigned char *p_buf,
 878         int p_buf_len)
 879 {
 880         unsigned char buf[VPD_TMP_BUF_SIZE];
 881         int ret = 0;
 882         int len;
 883
 884         memset(buf, 0, VPD_TMP_BUF_SIZE);
 885         len = sprintf(buf, "T10 VPD Identifier Association: ");
 886
 887         switch (vpd->association) {
 888         case 0x00:
 889                 sprintf(buf+len, "addressed logical unit\n");
 890                 break;
 891         case 0x10:
 892                 sprintf(buf+len, "target port\n");
 893                 break;
 894         case 0x20:
 895                 sprintf(buf+len, "SCSI target device\n");
 896                 break;
 897         default:
 898                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 899                 ret = -EINVAL;
 900                 break;
 901         }
 902
 903         if (p_buf)
 904                 strncpy(p_buf, buf, p_buf_len);
 905         else
 906                 pr_debug("%s", buf);
 907
 908         return ret;
 909 }
 910
 911 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 912 {
 913         /*
 914          * The VPD identification association..
 915          *
 916          * from spc3r23.pdf Section 7.6.3.1 Table 297
 917          */
 918         vpd->association = (page_83[1] & 0x30);
 919         return transport_dump_vpd_assoc(vpd, NULL, 0);
 920 }
 921 EXPORT_SYMBOL(transport_set_vpd_assoc);
 922
 923 int transport_dump_vpd_ident_type(
 924         struct t10_vpd *vpd,
 925         unsigned char *p_buf,
 926         int p_buf_len)
 927 {
 928         unsigned char buf[VPD_TMP_BUF_SIZE];
 929         int ret = 0;
 930         int len;
 931
 932         memset(buf, 0, VPD_TMP_BUF_SIZE);
 933         len = sprintf(buf, "T10 VPD Identifier Type: ");
 934
 935         switch (vpd->device_identifier_type) {
 936         case 0x00:
 937                 sprintf(buf+len, "Vendor specific\n");
 938                 break;
 939         case 0x01:
 940                 sprintf(buf+len, "T10 Vendor ID based\n");
 941                 break;
 942         case 0x02:
 943                 sprintf(buf+len, "EUI-64 based\n");
 944                 break;
 945         case 0x03:
 946                 sprintf(buf+len, "NAA\n");
 947                 break;
 948         case 0x04:
 949                 sprintf(buf+len, "Relative target port identifier\n");
 950                 break;
 951         case 0x08:
 952                 sprintf(buf+len, "SCSI name string\n");
 953                 break;
 954         default:
 955                 sprintf(buf+len, "Unsupported: 0x%02x\n",
 956                                 vpd->device_identifier_type);
 957                 ret = -EINVAL;
 958                 break;
 959         }
 960
 961         if (p_buf) {
 962                 if (p_buf_len < strlen(buf)+1)
 963                         return -EINVAL;
 964                 strncpy(p_buf, buf, p_buf_len);
 965         } else {
 966                 pr_debug("%s", buf);
 967         }
 968
 969         return ret;
 970 }
 971
 972 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
 973 {
 974         /*
 975          * The VPD identifier type..
 976          *
 977          * from spc3r23.pdf Section 7.6.3.1 Table 298
 978          */
 979         vpd->device_identifier_type = (page_83[1] & 0x0f);
 980         return transport_dump_vpd_ident_type(vpd, NULL, 0);
 981 }
 982 EXPORT_SYMBOL(transport_set_vpd_ident_type);
 983
 984 int transport_dump_vpd_ident(
 985         struct t10_vpd *vpd,
 986         unsigned char *p_buf,
 987         int p_buf_len)
 988 {
 989         unsigned char buf[VPD_TMP_BUF_SIZE];
 990         int ret = 0;
 991
 992         memset(buf, 0, VPD_TMP_BUF_SIZE);
 993
 994         switch (vpd->device_identifier_code_set) {
 995         case 0x01: /* Binary */
 996                 snprintf(buf, sizeof(buf),
 997                         "T10 VPD Binary Device Identifier: %s\n",
 998                         &vpd->device_identifier[0]);
 999                 break;
1000         case 0x02: /* ASCII */
1001                 snprintf(buf, sizeof(buf),
1002                         "T10 VPD ASCII Device Identifier: %s\n",
1003                         &vpd->device_identifier[0]);
1004                 break;
1005         case 0x03: /* UTF-8 */
1006                 snprintf(buf, sizeof(buf),
1007                         "T10 VPD UTF-8 Device Identifier: %s\n",
1008                         &vpd->device_identifier[0]);
1009                 break;
1010         default:
1011                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1012                         " 0x%02x", vpd->device_identifier_code_set);
1013                 ret = -EINVAL;
1014                 break;
1015         }
1016
1017         if (p_buf)
1018                 strncpy(p_buf, buf, p_buf_len);
1019         else
1020                 pr_debug("%s", buf);
1021
1022         return ret;
1023 }
1024
1025 int
1026 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1027 {
1028         static const char hex_str[] = "0123456789abcdef";
1029         int j = 0, i = 4; /* offset to start of the identifier */
1030
1031         /*
1032          * The VPD Code Set (encoding)
1033          *
1034          * from spc3r23.pdf Section 7.6.3.1 Table 296
1035          */
1036         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1037         switch (vpd->device_identifier_code_set) {
1038         case 0x01: /* Binary */
1039                 vpd->device_identifier[j++] =
1040                                 hex_str[vpd->device_identifier_type];
1041                 while (i < (4 + page_83[3])) {
1042                         vpd->device_identifier[j++] =
1043                                 hex_str[(page_83[i] & 0xf0) >> 4];
1044                         vpd->device_identifier[j++] =
1045                                 hex_str[page_83[i] & 0x0f];
1046                         i++;
1047                 }
1048                 break;
1049         case 0x02: /* ASCII */
1050         case 0x03: /* UTF-8 */
1051                 while (i < (4 + page_83[3]))
1052                         vpd->device_identifier[j++] = page_83[i++];
1053                 break;
1054         default:
1055                 break;
1056         }
1057
1058         return transport_dump_vpd_ident(vpd, NULL, 0);
1059 }
1060 EXPORT_SYMBOL(transport_set_vpd_ident);
1061
1062 sense_reason_t
1063 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1064 {
1065         struct se_device *dev = cmd->se_dev;
1066
1067         if (cmd->unknown_data_length) {
1068                 cmd->data_length = size;
1069         } else if (size != cmd->data_length) {
1070                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1071                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1072                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1073                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1074
1075                 if (cmd->data_direction == DMA_TO_DEVICE) {
1076                         pr_err("Rejecting underflow/overflow"
1077                                         " WRITE data\n");
1078                         return TCM_INVALID_CDB_FIELD;
1079                 }
1080                 /*
1081                  * Reject READ_* or WRITE_* with overflow/underflow for
1082                  * type SCF_SCSI_DATA_CDB.
1083                  */
1084                 if (dev->dev_attrib.block_size != 512)  {
1085                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1086                                 " CDB on non 512-byte sector setup subsystem"
1087                                 " plugin: %s\n", dev->transport->name);
1088                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1089                         return TCM_INVALID_CDB_FIELD;
1090                 }
1091                 /*
1092                  * For the overflow case keep the existing fabric provided
1093                  * ->data_length.  Otherwise for the underflow case, reset
1094                  * ->data_length to the smaller SCSI expected data transfer
1095                  * length.
1096                  */
1097                 if (size > cmd->data_length) {
1098                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1099                         cmd->residual_count = (size - cmd->data_length);
1100                 } else {
1101                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1102                         cmd->residual_count = (cmd->data_length - size);
1103                         cmd->data_length = size;
1104                 }
1105         }
1106
1107         return 0;
1108
1109 }
1110
1111 /*
1112  * Used by fabric modules containing a local struct se_cmd within their
1113  * fabric dependent per I/O descriptor.
1114  */
1115 void transport_init_se_cmd(
1116         struct se_cmd *cmd,
1117         struct target_core_fabric_ops *tfo,
1118         struct se_session *se_sess,
1119         u32 data_length,
1120         int data_direction,
1121         int task_attr,
1122         unsigned char *sense_buffer)
1123 {
1124         INIT_LIST_HEAD(&cmd->se_delayed_node);
1125         INIT_LIST_HEAD(&cmd->se_qf_node);
1126         INIT_LIST_HEAD(&cmd->se_cmd_list);
1127         INIT_LIST_HEAD(&cmd->state_list);
1128         init_completion(&cmd->t_transport_stop_comp);
1129         init_completion(&cmd->cmd_wait_comp);
1130         init_completion(&cmd->task_stop_comp);
1131         spin_lock_init(&cmd->t_state_lock);
1132         kref_init(&cmd->cmd_kref);
1133         cmd->transport_state = CMD_T_DEV_ACTIVE;
1134
1135         cmd->se_tfo = tfo;
1136         cmd->se_sess = se_sess;
1137         cmd->data_length = data_length;
1138         cmd->data_direction = data_direction;
1139         cmd->sam_task_attr = task_attr;
1140         cmd->sense_buffer = sense_buffer;
1141
1142         cmd->state_active = false;
1143 }
1144 EXPORT_SYMBOL(transport_init_se_cmd);
1145
1146 static sense_reason_t
1147 transport_check_alloc_task_attr(struct se_cmd *cmd)
1148 {
1149         struct se_device *dev = cmd->se_dev;
1150
1151         /*
1152          * Check if SAM Task Attribute emulation is enabled for this
1153          * struct se_device storage object
1154          */
1155         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1156                 return 0;
1157
1158         if (cmd->sam_task_attr == MSG_ACA_TAG) {
1159                 pr_debug("SAM Task Attribute ACA"
1160                         " emulation is not supported\n");
1161                 return TCM_INVALID_CDB_FIELD;
1162         }
1163         /*
1164          * Used to determine when ORDERED commands should go from
1165          * Dormant to Active status.
1166          */
1167         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1168         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1169                         cmd->se_ordered_id, cmd->sam_task_attr,
1170                         dev->transport->name);
1171         return 0;
1172 }
1173
1174 sense_reason_t
1175 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1176 {
1177         struct se_device *dev = cmd->se_dev;
1178         sense_reason_t ret;
1179
1180         /*
1181          * Ensure that the received CDB is less than the max (252 + 8) bytes
1182          * for VARIABLE_LENGTH_CMD
1183          */
1184         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1185                 pr_err("Received SCSI CDB with command_size: %d that"
1186                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1187                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1188                 return TCM_INVALID_CDB_FIELD;
1189         }
1190         /*
1191          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1192          * allocate the additional extended CDB buffer now..  Otherwise
1193          * setup the pointer from __t_task_cdb to t_task_cdb.
1194          */
1195         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1196                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1197                                                 GFP_KERNEL);
1198                 if (!cmd->t_task_cdb) {
1199                         pr_err("Unable to allocate cmd->t_task_cdb"
1200                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1201                                 scsi_command_size(cdb),
1202                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1203                         return TCM_OUT_OF_RESOURCES;
1204                 }
1205         } else
1206                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1207         /*
1208          * Copy the original CDB into cmd->
1209          */
1210         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1211
1212         trace_target_sequencer_start(cmd);
1213
1214         /*
1215          * Check for an existing UNIT ATTENTION condition
1216          */
1217         ret = target_scsi3_ua_check(cmd);
1218         if (ret)
1219                 return ret;
1220
1221         ret = target_alua_state_check(cmd);
1222         if (ret)
1223                 return ret;
1224
1225         ret = target_check_reservation(cmd);
1226         if (ret) {
1227                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1228                 return ret;
1229         }
1230
1231         ret = dev->transport->parse_cdb(cmd);
1232         if (ret)
1233                 return ret;
1234
1235         ret = transport_check_alloc_task_attr(cmd);
1236         if (ret)
1237                 return ret;
1238
1239         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1240
1241         spin_lock(&cmd->se_lun->lun_sep_lock);
1242         if (cmd->se_lun->lun_sep)
1243                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1244         spin_unlock(&cmd->se_lun->lun_sep_lock);
1245         return 0;
1246 }
1247 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1248
1249 /*
1250  * Used by fabric module frontends to queue tasks directly.
1251  * Many only be used from process context only
1252  */
1253 int transport_handle_cdb_direct(
1254         struct se_cmd *cmd)
1255 {
1256         sense_reason_t ret;
1257
1258         if (!cmd->se_lun) {
1259                 dump_stack();
1260                 pr_err("cmd->se_lun is NULL\n");
1261                 return -EINVAL;
1262         }
1263         if (in_interrupt()) {
1264                 dump_stack();
1265                 pr_err("transport_generic_handle_cdb cannot be called"
1266                                 " from interrupt context\n");
1267                 return -EINVAL;
1268         }
1269         /*
1270          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1271          * outstanding descriptors are handled correctly during shutdown via
1272          * transport_wait_for_tasks()
1273          *
1274          * Also, we don't take cmd->t_state_lock here as we only expect
1275          * this to be called for initial descriptor submission.
1276          */
1277         cmd->t_state = TRANSPORT_NEW_CMD;
1278         cmd->transport_state |= CMD_T_ACTIVE;
1279
1280         /*
1281          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1282          * so follow TRANSPORT_NEW_CMD processing thread context usage
1283          * and call transport_generic_request_failure() if necessary..
1284          */
1285         ret = transport_generic_new_cmd(cmd);
1286         if (ret)
1287                 transport_generic_request_failure(cmd, ret);
1288         return 0;
1289 }
1290 EXPORT_SYMBOL(transport_handle_cdb_direct);
1291
1292 sense_reason_t
1293 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1294                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1295 {
1296         if (!sgl || !sgl_count)
1297                 return 0;
1298
1299         /*
1300          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1301          * scatterlists already have been set to follow what the fabric
1302          * passes for the original expected data transfer length.
1303          */
1304         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1305                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1306                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1307                 return TCM_INVALID_CDB_FIELD;
1308         }
1309
1310         cmd->t_data_sg = sgl;
1311         cmd->t_data_nents = sgl_count;
1312
1313         if (sgl_bidi && sgl_bidi_count) {
1314                 cmd->t_bidi_data_sg = sgl_bidi;
1315                 cmd->t_bidi_data_nents = sgl_bidi_count;
1316         }
1317         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1318         return 0;
1319 }
1320
1321 /*
1322  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1323  *                       se_cmd + use pre-allocated SGL memory.
1324  *
1325  * @se_cmd: command descriptor to submit
1326  * @se_sess: associated se_sess for endpoint
1327  * @cdb: pointer to SCSI CDB
1328  * @sense: pointer to SCSI sense buffer
1329  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1330  * @data_length: fabric expected data transfer length
1331  * @task_addr: SAM task attribute
1332  * @data_dir: DMA data direction
1333  * @flags: flags for command submission from target_sc_flags_tables
1334  * @sgl: struct scatterlist memory for unidirectional mapping
1335  * @sgl_count: scatterlist count for unidirectional mapping
1336  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1337  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1338  * @sgl_prot: struct scatterlist memory protection information
1339  * @sgl_prot_count: scatterlist count for protection information
1340  *
1341  * Returns non zero to signal active I/O shutdown failure.  All other
1342  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1343  * but still return zero here.
1344  *
1345  * This may only be called from process context, and also currently
1346  * assumes internal allocation of fabric payload buffer by target-core.
1347  */
1348 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1349                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1350                 u32 data_length, int task_attr, int data_dir, int flags,
1351                 struct scatterlist *sgl, u32 sgl_count,
1352                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1353                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1354 {
1355         struct se_portal_group *se_tpg;
1356         sense_reason_t rc;
1357         int ret;
1358
1359         se_tpg = se_sess->se_tpg;
1360         BUG_ON(!se_tpg);
1361         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1362         BUG_ON(in_interrupt());
1363         /*
1364          * Initialize se_cmd for target operation.  From this point
1365          * exceptions are handled by sending exception status via
1366          * target_core_fabric_ops->queue_status() callback
1367          */
1368         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1369                                 data_length, data_dir, task_attr, sense);
1370         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1371                 se_cmd->unknown_data_length = 1;
1372         /*
1373          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1374          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1375          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1376          * kref_put() to happen during fabric packet acknowledgement.
1377          */
1378         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1379         if (ret)
1380                 return ret;
1381         /*
1382          * Signal bidirectional data payloads to target-core
1383          */
1384         if (flags & TARGET_SCF_BIDI_OP)
1385                 se_cmd->se_cmd_flags |= SCF_BIDI;
1386         /*
1387          * Locate se_lun pointer and attach it to struct se_cmd
1388          */
1389         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1390         if (rc) {
1391                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1392                 target_put_sess_cmd(se_sess, se_cmd);
1393                 return 0;
1394         }
1395
1396         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1397         if (rc != 0) {
1398                 transport_generic_request_failure(se_cmd, rc);
1399                 return 0;
1400         }
1401
1402         /*
1403          * Save pointers for SGLs containing protection information,
1404          * if present.
1405          */
1406         if (sgl_prot_count) {
1407                 se_cmd->t_prot_sg = sgl_prot;
1408                 se_cmd->t_prot_nents = sgl_prot_count;
1409         }
1410
1411         /*
1412          * When a non zero sgl_count has been passed perform SGL passthrough
1413          * mapping for pre-allocated fabric memory instead of having target
1414          * core perform an internal SGL allocation..
1415          */
1416         if (sgl_count != 0) {
1417                 BUG_ON(!sgl);
1418
1419                 /*
1420                  * A work-around for tcm_loop as some userspace code via
1421                  * scsi-generic do not memset their associated read buffers,
1422                  * so go ahead and do that here for type non-data CDBs.  Also
1423                  * note that this is currently guaranteed to be a single SGL
1424                  * for this case by target core in target_setup_cmd_from_cdb()
1425                  * -> transport_generic_cmd_sequencer().
1426                  */
1427                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1428                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1429                         unsigned char *buf = NULL;
1430
1431                         if (sgl)
1432                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1433
1434                         if (buf) {
1435                                 memset(buf, 0, sgl->length);
1436                                 kunmap(sg_page(sgl));
1437                         }
1438                 }
1439
1440                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1441                                 sgl_bidi, sgl_bidi_count);
1442                 if (rc != 0) {
1443                         transport_generic_request_failure(se_cmd, rc);
1444                         return 0;
1445                 }
1446         }
1447
1448         /*
1449          * Check if we need to delay processing because of ALUA
1450          * Active/NonOptimized primary access state..
1451          */
1452         core_alua_check_nonop_delay(se_cmd);
1453
1454         transport_handle_cdb_direct(se_cmd);
1455         return 0;
1456 }
1457 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1458
1459 /*
1460  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1461  *
1462  * @se_cmd: command descriptor to submit
1463  * @se_sess: associated se_sess for endpoint
1464  * @cdb: pointer to SCSI CDB
1465  * @sense: pointer to SCSI sense buffer
1466  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1467  * @data_length: fabric expected data transfer length
1468  * @task_addr: SAM task attribute
1469  * @data_dir: DMA data direction
1470  * @flags: flags for command submission from target_sc_flags_tables
1471  *
1472  * Returns non zero to signal active I/O shutdown failure.  All other
1473  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1474  * but still return zero here.
1475  *
1476  * This may only be called from process context, and also currently
1477  * assumes internal allocation of fabric payload buffer by target-core.
1478  *
1479  * It also assumes interal target core SGL memory allocation.
1480  */
1481 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1482                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1483                 u32 data_length, int task_attr, int data_dir, int flags)
1484 {
1485         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1486                         unpacked_lun, data_length, task_attr, data_dir,
1487                         flags, NULL, 0, NULL, 0, NULL, 0);
1488 }
1489 EXPORT_SYMBOL(target_submit_cmd);
1490
1491 static void target_complete_tmr_failure(struct work_struct *work)
1492 {
1493         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1494
1495         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1496         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1497
1498         transport_cmd_check_stop_to_fabric(se_cmd);
1499 }
1500
1501 /**
1502  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1503  *                     for TMR CDBs
1504  *
1505  * @se_cmd: command descriptor to submit
1506  * @se_sess: associated se_sess for endpoint
1507  * @sense: pointer to SCSI sense buffer
1508  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1509  * @fabric_context: fabric context for TMR req
1510  * @tm_type: Type of TM request
1511  * @gfp: gfp type for caller
1512  * @tag: referenced task tag for TMR_ABORT_TASK
1513  * @flags: submit cmd flags
1514  *
1515  * Callable from all contexts.
1516  **/
1517
1518 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1519                 unsigned char *sense, u32 unpacked_lun,
1520                 void *fabric_tmr_ptr, unsigned char tm_type,
1521                 gfp_t gfp, unsigned int tag, int flags)
1522 {
1523         struct se_portal_group *se_tpg;
1524         int ret;
1525
1526         se_tpg = se_sess->se_tpg;
1527         BUG_ON(!se_tpg);
1528
1529         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1530                               0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1531         /*
1532          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1533          * allocation failure.
1534          */
1535         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1536         if (ret < 0)
1537                 return -ENOMEM;
1538
1539         if (tm_type == TMR_ABORT_TASK)
1540                 se_cmd->se_tmr_req->ref_task_tag = tag;
1541
1542         /* See target_submit_cmd for commentary */
1543         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1544         if (ret) {
1545                 core_tmr_release_req(se_cmd->se_tmr_req);
1546                 return ret;
1547         }
1548
1549         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1550         if (ret) {
1551                 /*
1552                  * For callback during failure handling, push this work off
1553                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1554                  */
1555                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1556                 schedule_work(&se_cmd->work);
1557                 return 0;
1558         }
1559         transport_generic_handle_tmr(se_cmd);
1560         return 0;
1561 }
1562 EXPORT_SYMBOL(target_submit_tmr);
1563
1564 /*
1565  * If the cmd is active, request it to be stopped and sleep until it
1566  * has completed.
1567  */
1568 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1569 {
1570         bool was_active = false;
1571
1572         if (cmd->transport_state & CMD_T_BUSY) {
1573                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1574                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1575
1576                 pr_debug("cmd %p waiting to complete\n", cmd);
1577                 wait_for_completion(&cmd->task_stop_comp);
1578                 pr_debug("cmd %p stopped successfully\n", cmd);
1579
1580                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1581                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1582                 cmd->transport_state &= ~CMD_T_BUSY;
1583                 was_active = true;
1584         }
1585
1586         return was_active;
1587 }
1588
1589 /*
1590  * Handle SAM-esque emulation for generic transport request failures.
1591  */
1592 void transport_generic_request_failure(struct se_cmd *cmd,
1593                 sense_reason_t sense_reason)
1594 {
1595         int ret = 0;
1596
1597         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1598                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1599                 cmd->t_task_cdb[0]);
1600         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1601                 cmd->se_tfo->get_cmd_state(cmd),
1602                 cmd->t_state, sense_reason);
1603         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1604                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1605                 (cmd->transport_state & CMD_T_STOP) != 0,
1606                 (cmd->transport_state & CMD_T_SENT) != 0);
1607
1608         /*
1609          * For SAM Task Attribute emulation for failed struct se_cmd
1610          */
1611         transport_complete_task_attr(cmd);
1612         /*
1613          * Handle special case for COMPARE_AND_WRITE failure, where the
1614          * callback is expected to drop the per device ->caw_mutex.
1615          */
1616         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1617              cmd->transport_complete_callback)
1618                 cmd->transport_complete_callback(cmd);
1619
1620         switch (sense_reason) {
1621         case TCM_NON_EXISTENT_LUN:
1622         case TCM_UNSUPPORTED_SCSI_OPCODE:
1623         case TCM_INVALID_CDB_FIELD:
1624         case TCM_INVALID_PARAMETER_LIST:
1625         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1626         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1627         case TCM_UNKNOWN_MODE_PAGE:
1628         case TCM_WRITE_PROTECTED:
1629         case TCM_ADDRESS_OUT_OF_RANGE:
1630         case TCM_CHECK_CONDITION_ABORT_CMD:
1631         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1632         case TCM_CHECK_CONDITION_NOT_READY:
1633         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1634         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1635         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1636                 break;
1637         case TCM_OUT_OF_RESOURCES:
1638                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1639                 break;
1640         case TCM_RESERVATION_CONFLICT:
1641                 /*
1642                  * No SENSE Data payload for this case, set SCSI Status
1643                  * and queue the response to $FABRIC_MOD.
1644                  *
1645                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1646                  */
1647                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1648                 /*
1649                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1650                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1651                  * CONFLICT STATUS.
1652                  *
1653                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1654                  */
1655                 if (cmd->se_sess &&
1656                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1657                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1658                                 cmd->orig_fe_lun, 0x2C,
1659                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1660
1661                 trace_target_cmd_complete(cmd);
1662                 ret = cmd->se_tfo-> queue_status(cmd);
1663                 if (ret == -EAGAIN || ret == -ENOMEM)
1664                         goto queue_full;
1665                 goto check_stop;
1666         default:
1667                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1668                         cmd->t_task_cdb[0], sense_reason);
1669                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1670                 break;
1671         }
1672
1673         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1674         if (ret == -EAGAIN || ret == -ENOMEM)
1675                 goto queue_full;
1676
1677 check_stop:
1678         transport_lun_remove_cmd(cmd);
1679         if (!transport_cmd_check_stop_to_fabric(cmd))
1680                 ;
1681         return;
1682
1683 queue_full:
1684         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1685         transport_handle_queue_full(cmd, cmd->se_dev);
1686 }
1687 EXPORT_SYMBOL(transport_generic_request_failure);
1688
1689 void __target_execute_cmd(struct se_cmd *cmd)
1690 {
1691         sense_reason_t ret;
1692
1693         if (cmd->execute_cmd) {
1694                 ret = cmd->execute_cmd(cmd);
1695                 if (ret) {
1696                         spin_lock_irq(&cmd->t_state_lock);
1697                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1698                         spin_unlock_irq(&cmd->t_state_lock);
1699
1700                         transport_generic_request_failure(cmd, ret);
1701                 }
1702         }
1703 }
1704
1705 static bool target_handle_task_attr(struct se_cmd *cmd)
1706 {
1707         struct se_device *dev = cmd->se_dev;
1708
1709         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1710                 return false;
1711
1712         /*
1713          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1714          * to allow the passed struct se_cmd list of tasks to the front of the list.
1715          */
1716         switch (cmd->sam_task_attr) {
1717         case MSG_HEAD_TAG:
1718                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1719                          "se_ordered_id: %u\n",
1720                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1721                 return false;
1722         case MSG_ORDERED_TAG:
1723                 atomic_inc_mb(&dev->dev_ordered_sync);
1724
1725                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1726                          " se_ordered_id: %u\n",
1727                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1728
1729                 /*
1730                  * Execute an ORDERED command if no other older commands
1731                  * exist that need to be completed first.
1732                  */
1733                 if (!atomic_read(&dev->simple_cmds))
1734                         return false;
1735                 break;
1736         default:
1737                 /*
1738                  * For SIMPLE and UNTAGGED Task Attribute commands
1739                  */
1740                 atomic_inc_mb(&dev->simple_cmds);
1741                 break;
1742         }
1743
1744         if (atomic_read(&dev->dev_ordered_sync) == 0)
1745                 return false;
1746
1747         spin_lock(&dev->delayed_cmd_lock);
1748         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1749         spin_unlock(&dev->delayed_cmd_lock);
1750
1751         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1752                 " delayed CMD list, se_ordered_id: %u\n",
1753                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1754                 cmd->se_ordered_id);
1755         return true;
1756 }
1757
1758 void target_execute_cmd(struct se_cmd *cmd)
1759 {
1760         /*
1761          * If the received CDB has aleady been aborted stop processing it here.
1762          */
1763         if (transport_check_aborted_status(cmd, 1))
1764                 return;
1765
1766         /*
1767          * Determine if frontend context caller is requesting the stopping of
1768          * this command for frontend exceptions.
1769          */
1770         spin_lock_irq(&cmd->t_state_lock);
1771         if (cmd->transport_state & CMD_T_STOP) {
1772                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1773                         __func__, __LINE__,
1774                         cmd->se_tfo->get_task_tag(cmd));
1775
1776                 spin_unlock_irq(&cmd->t_state_lock);
1777                 complete_all(&cmd->t_transport_stop_comp);
1778                 return;
1779         }
1780
1781         cmd->t_state = TRANSPORT_PROCESSING;
1782         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1783         spin_unlock_irq(&cmd->t_state_lock);
1784         /*
1785          * Perform WRITE_INSERT of PI using software emulation when backend
1786          * device has PI enabled, if the transport has not already generated
1787          * PI using hardware WRITE_INSERT offload.
1788          */
1789         if (cmd->prot_op == TARGET_PROT_DOUT_INSERT) {
1790                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1791                         sbc_dif_generate(cmd);
1792         }
1793
1794         if (target_handle_task_attr(cmd)) {
1795                 spin_lock_irq(&cmd->t_state_lock);
1796                 cmd->transport_state &= ~CMD_T_BUSY|CMD_T_SENT;
1797                 spin_unlock_irq(&cmd->t_state_lock);
1798                 return;
1799         }
1800
1801         __target_execute_cmd(cmd);
1802 }
1803 EXPORT_SYMBOL(target_execute_cmd);
1804
1805 /*
1806  * Process all commands up to the last received ORDERED task attribute which
1807  * requires another blocking boundary
1808  */
1809 static void target_restart_delayed_cmds(struct se_device *dev)
1810 {
1811         for (;;) {
1812                 struct se_cmd *cmd;
1813
1814                 spin_lock(&dev->delayed_cmd_lock);
1815                 if (list_empty(&dev->delayed_cmd_list)) {
1816                         spin_unlock(&dev->delayed_cmd_lock);
1817                         break;
1818                 }
1819
1820                 cmd = list_entry(dev->delayed_cmd_list.next,
1821                                  struct se_cmd, se_delayed_node);
1822                 list_del(&cmd->se_delayed_node);
1823                 spin_unlock(&dev->delayed_cmd_lock);
1824
1825                 __target_execute_cmd(cmd);
1826
1827                 if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1828                         break;
1829         }
1830 }
1831
1832 /*
1833  * Called from I/O completion to determine which dormant/delayed
1834  * and ordered cmds need to have their tasks added to the execution queue.
1835  */
1836 static void transport_complete_task_attr(struct se_cmd *cmd)
1837 {
1838         struct se_device *dev = cmd->se_dev;
1839
1840         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1841                 return;
1842
1843         if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1844                 atomic_dec_mb(&dev->simple_cmds);
1845                 dev->dev_cur_ordered_id++;
1846                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1847                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1848                         cmd->se_ordered_id);
1849         } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1850                 dev->dev_cur_ordered_id++;
1851                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1852                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1853                         cmd->se_ordered_id);
1854         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1855                 atomic_dec_mb(&dev->dev_ordered_sync);
1856
1857                 dev->dev_cur_ordered_id++;
1858                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1859                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1860         }
1861
1862         target_restart_delayed_cmds(dev);
1863 }
1864
1865 static void transport_complete_qf(struct se_cmd *cmd)
1866 {
1867         int ret = 0;
1868
1869         transport_complete_task_attr(cmd);
1870
1871         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1872                 trace_target_cmd_complete(cmd);
1873                 ret = cmd->se_tfo->queue_status(cmd);
1874                 goto out;
1875         }
1876
1877         switch (cmd->data_direction) {
1878         case DMA_FROM_DEVICE:
1879                 trace_target_cmd_complete(cmd);
1880                 ret = cmd->se_tfo->queue_data_in(cmd);
1881                 break;
1882         case DMA_TO_DEVICE:
1883                 if (cmd->se_cmd_flags & SCF_BIDI) {
1884                         ret = cmd->se_tfo->queue_data_in(cmd);
1885                         if (ret < 0)
1886                                 break;
1887                 }
1888                 /* Fall through for DMA_TO_DEVICE */
1889         case DMA_NONE:
1890                 trace_target_cmd_complete(cmd);
1891                 ret = cmd->se_tfo->queue_status(cmd);
1892                 break;
1893         default:
1894                 break;
1895         }
1896
1897 out:
1898         if (ret < 0) {
1899                 transport_handle_queue_full(cmd, cmd->se_dev);
1900                 return;
1901         }
1902         transport_lun_remove_cmd(cmd);
1903         transport_cmd_check_stop_to_fabric(cmd);
1904 }
1905
1906 static void transport_handle_queue_full(
1907         struct se_cmd *cmd,
1908         struct se_device *dev)
1909 {
1910         spin_lock_irq(&dev->qf_cmd_lock);
1911         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1912         atomic_inc_mb(&dev->dev_qf_count);
1913         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1914
1915         schedule_work(&cmd->se_dev->qf_work_queue);
1916 }
1917
1918 static bool target_check_read_strip(struct se_cmd *cmd)
1919 {
1920         sense_reason_t rc;
1921
1922         if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
1923                 rc = sbc_dif_read_strip(cmd);
1924                 if (rc) {
1925                         cmd->pi_err = rc;
1926                         return true;
1927                 }
1928         }
1929
1930         return false;
1931 }
1932
1933 static void target_complete_ok_work(struct work_struct *work)
1934 {
1935         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1936         int ret;
1937
1938         /*
1939          * Check if we need to move delayed/dormant tasks from cmds on the
1940          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1941          * Attribute.
1942          */
1943         transport_complete_task_attr(cmd);
1944
1945         /*
1946          * Check to schedule QUEUE_FULL work, or execute an existing
1947          * cmd->transport_qf_callback()
1948          */
1949         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1950                 schedule_work(&cmd->se_dev->qf_work_queue);
1951
1952         /*
1953          * Check if we need to send a sense buffer from
1954          * the struct se_cmd in question.
1955          */
1956         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1957                 WARN_ON(!cmd->scsi_status);
1958                 ret = transport_send_check_condition_and_sense(
1959                                         cmd, 0, 1);
1960                 if (ret == -EAGAIN || ret == -ENOMEM)
1961                         goto queue_full;
1962
1963                 transport_lun_remove_cmd(cmd);
1964                 transport_cmd_check_stop_to_fabric(cmd);
1965                 return;
1966         }
1967         /*
1968          * Check for a callback, used by amongst other things
1969          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
1970          */
1971         if (cmd->transport_complete_callback) {
1972                 sense_reason_t rc;
1973
1974                 rc = cmd->transport_complete_callback(cmd);
1975                 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
1976                         return;
1977                 } else if (rc) {
1978                         ret = transport_send_check_condition_and_sense(cmd,
1979                                                 rc, 0);
1980                         if (ret == -EAGAIN || ret == -ENOMEM)
1981                                 goto queue_full;
1982
1983                         transport_lun_remove_cmd(cmd);
1984                         transport_cmd_check_stop_to_fabric(cmd);
1985                         return;
1986                 }
1987         }
1988
1989         switch (cmd->data_direction) {
1990         case DMA_FROM_DEVICE:
1991                 spin_lock(&cmd->se_lun->lun_sep_lock);
1992                 if (cmd->se_lun->lun_sep) {
1993                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1994                                         cmd->data_length;
1995                 }
1996                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1997                 /*
1998                  * Perform READ_STRIP of PI using software emulation when
1999                  * backend had PI enabled, if the transport will not be
2000                  * performing hardware READ_STRIP offload.
2001                  */
2002                 if (cmd->prot_op == TARGET_PROT_DIN_STRIP &&
2003                     target_check_read_strip(cmd)) {
2004                         ret = transport_send_check_condition_and_sense(cmd,
2005                                                 cmd->pi_err, 0);
2006                         if (ret == -EAGAIN || ret == -ENOMEM)
2007                                 goto queue_full;
2008
2009                         transport_lun_remove_cmd(cmd);
2010                         transport_cmd_check_stop_to_fabric(cmd);
2011                         return;
2012                 }
2013
2014                 trace_target_cmd_complete(cmd);
2015                 ret = cmd->se_tfo->queue_data_in(cmd);
2016                 if (ret == -EAGAIN || ret == -ENOMEM)
2017                         goto queue_full;
2018                 break;
2019         case DMA_TO_DEVICE:
2020                 spin_lock(&cmd->se_lun->lun_sep_lock);
2021                 if (cmd->se_lun->lun_sep) {
2022                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
2023                                 cmd->data_length;
2024                 }
2025                 spin_unlock(&cmd->se_lun->lun_sep_lock);
2026                 /*
2027                  * Check if we need to send READ payload for BIDI-COMMAND
2028                  */
2029                 if (cmd->se_cmd_flags & SCF_BIDI) {
2030                         spin_lock(&cmd->se_lun->lun_sep_lock);
2031                         if (cmd->se_lun->lun_sep) {
2032                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
2033                                         cmd->data_length;
2034                         }
2035                         spin_unlock(&cmd->se_lun->lun_sep_lock);
2036                         ret = cmd->se_tfo->queue_data_in(cmd);
2037                         if (ret == -EAGAIN || ret == -ENOMEM)
2038                                 goto queue_full;
2039                         break;
2040                 }
2041                 /* Fall through for DMA_TO_DEVICE */
2042         case DMA_NONE:
2043                 trace_target_cmd_complete(cmd);
2044                 ret = cmd->se_tfo->queue_status(cmd);
2045                 if (ret == -EAGAIN || ret == -ENOMEM)
2046                         goto queue_full;
2047                 break;
2048         default:
2049                 break;
2050         }
2051
2052         transport_lun_remove_cmd(cmd);
2053         transport_cmd_check_stop_to_fabric(cmd);
2054         return;
2055
2056 queue_full:
2057         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2058                 " data_direction: %d\n", cmd, cmd->data_direction);
2059         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2060         transport_handle_queue_full(cmd, cmd->se_dev);
2061 }
2062
2063 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2064 {
2065         struct scatterlist *sg;
2066         int count;
2067
2068         for_each_sg(sgl, sg, nents, count)
2069                 __free_page(sg_page(sg));
2070
2071         kfree(sgl);
2072 }
2073
2074 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2075 {
2076         /*
2077          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2078          * emulation, and free + reset pointers if necessary..
2079          */
2080         if (!cmd->t_data_sg_orig)
2081                 return;
2082
2083         kfree(cmd->t_data_sg);
2084         cmd->t_data_sg = cmd->t_data_sg_orig;
2085         cmd->t_data_sg_orig = NULL;
2086         cmd->t_data_nents = cmd->t_data_nents_orig;
2087         cmd->t_data_nents_orig = 0;
2088 }
2089
2090 static inline void transport_free_pages(struct se_cmd *cmd)
2091 {
2092         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2093                 transport_reset_sgl_orig(cmd);
2094                 return;
2095         }
2096         transport_reset_sgl_orig(cmd);
2097
2098         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2099         cmd->t_data_sg = NULL;
2100         cmd->t_data_nents = 0;
2101
2102         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2103         cmd->t_bidi_data_sg = NULL;
2104         cmd->t_bidi_data_nents = 0;
2105
2106         transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2107         cmd->t_prot_sg = NULL;
2108         cmd->t_prot_nents = 0;
2109 }
2110
2111 /**
2112  * transport_release_cmd - free a command
2113  * @cmd:       command to free
2114  *
2115  * This routine unconditionally frees a command, and reference counting
2116  * or list removal must be done in the caller.
2117  */
2118 static int transport_release_cmd(struct se_cmd *cmd)
2119 {
2120         BUG_ON(!cmd->se_tfo);
2121
2122         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2123                 core_tmr_release_req(cmd->se_tmr_req);
2124         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2125                 kfree(cmd->t_task_cdb);
2126         /*
2127          * If this cmd has been setup with target_get_sess_cmd(), drop
2128          * the kref and call ->release_cmd() in kref callback.
2129          */
2130         return target_put_sess_cmd(cmd->se_sess, cmd);
2131 }
2132
2133 /**
2134  * transport_put_cmd - release a reference to a command
2135  * @cmd:       command to release
2136  *
2137  * This routine releases our reference to the command and frees it if possible.
2138  */
2139 static int transport_put_cmd(struct se_cmd *cmd)
2140 {
2141         transport_free_pages(cmd);
2142         return transport_release_cmd(cmd);
2143 }
2144
2145 void *transport_kmap_data_sg(struct se_cmd *cmd)
2146 {
2147         struct scatterlist *sg = cmd->t_data_sg;
2148         struct page **pages;
2149         int i;
2150
2151         /*
2152          * We need to take into account a possible offset here for fabrics like
2153          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2154          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2155          */
2156         if (!cmd->t_data_nents)
2157                 return NULL;
2158
2159         BUG_ON(!sg);
2160         if (cmd->t_data_nents == 1)
2161                 return kmap(sg_page(sg)) + sg->offset;
2162
2163         /* >1 page. use vmap */
2164         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2165         if (!pages)
2166                 return NULL;
2167
2168         /* convert sg[] to pages[] */
2169         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2170                 pages[i] = sg_page(sg);
2171         }
2172
2173         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2174         kfree(pages);
2175         if (!cmd->t_data_vmap)
2176                 return NULL;
2177
2178         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2179 }
2180 EXPORT_SYMBOL(transport_kmap_data_sg);
2181
2182 void transport_kunmap_data_sg(struct se_cmd *cmd)
2183 {
2184         if (!cmd->t_data_nents) {
2185                 return;
2186         } else if (cmd->t_data_nents == 1) {
2187                 kunmap(sg_page(cmd->t_data_sg));
2188                 return;
2189         }
2190
2191         vunmap(cmd->t_data_vmap);
2192         cmd->t_data_vmap = NULL;
2193 }
2194 EXPORT_SYMBOL(transport_kunmap_data_sg);
2195
2196 int
2197 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2198                  bool zero_page)
2199 {
2200         struct scatterlist *sg;
2201         struct page *page;
2202         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2203         unsigned int nent;
2204         int i = 0;
2205
2206         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2207         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2208         if (!sg)
2209                 return -ENOMEM;
2210
2211         sg_init_table(sg, nent);
2212
2213         while (length) {
2214                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2215                 page = alloc_page(GFP_KERNEL | zero_flag);
2216                 if (!page)
2217                         goto out;
2218
2219                 sg_set_page(&sg[i], page, page_len, 0);
2220                 length -= page_len;
2221                 i++;
2222         }
2223         *sgl = sg;
2224         *nents = nent;
2225         return 0;
2226
2227 out:
2228         while (i > 0) {
2229                 i--;
2230                 __free_page(sg_page(&sg[i]));
2231         }
2232         kfree(sg);
2233         return -ENOMEM;
2234 }
2235
2236 /*
2237  * Allocate any required resources to execute the command.  For writes we
2238  * might not have the payload yet, so notify the fabric via a call to
2239  * ->write_pending instead. Otherwise place it on the execution queue.
2240  */
2241 sense_reason_t
2242 transport_generic_new_cmd(struct se_cmd *cmd)
2243 {
2244         int ret = 0;
2245
2246         /*
2247          * Determine is the TCM fabric module has already allocated physical
2248          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2249          * beforehand.
2250          */
2251         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2252             cmd->data_length) {
2253                 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2254
2255                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2256                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2257                         u32 bidi_length;
2258
2259                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2260                                 bidi_length = cmd->t_task_nolb *
2261                                               cmd->se_dev->dev_attrib.block_size;
2262                         else
2263                                 bidi_length = cmd->data_length;
2264
2265                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2266                                                &cmd->t_bidi_data_nents,
2267                                                bidi_length, zero_flag);
2268                         if (ret < 0)
2269                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2270                 }
2271
2272                 if (cmd->prot_op != TARGET_PROT_NORMAL) {
2273                         ret = target_alloc_sgl(&cmd->t_prot_sg,
2274                                                &cmd->t_prot_nents,
2275                                                cmd->prot_length, true);
2276                         if (ret < 0)
2277                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2278                 }
2279
2280                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2281                                        cmd->data_length, zero_flag);
2282                 if (ret < 0)
2283                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2284         }
2285         /*
2286          * If this command is not a write we can execute it right here,
2287          * for write buffers we need to notify the fabric driver first
2288          * and let it call back once the write buffers are ready.
2289          */
2290         target_add_to_state_list(cmd);
2291         if (cmd->data_direction != DMA_TO_DEVICE) {
2292                 target_execute_cmd(cmd);
2293                 return 0;
2294         }
2295         transport_cmd_check_stop(cmd, false, true);
2296
2297         ret = cmd->se_tfo->write_pending(cmd);
2298         if (ret == -EAGAIN || ret == -ENOMEM)
2299                 goto queue_full;
2300
2301         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2302         WARN_ON(ret);
2303
2304         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2305
2306 queue_full:
2307         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2308         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2309         transport_handle_queue_full(cmd, cmd->se_dev);
2310         return 0;
2311 }
2312 EXPORT_SYMBOL(transport_generic_new_cmd);
2313
2314 static void transport_write_pending_qf(struct se_cmd *cmd)
2315 {
2316         int ret;
2317
2318         ret = cmd->se_tfo->write_pending(cmd);
2319         if (ret == -EAGAIN || ret == -ENOMEM) {
2320                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2321                          cmd);
2322                 transport_handle_queue_full(cmd, cmd->se_dev);
2323         }
2324 }
2325
2326 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2327 {
2328         unsigned long flags;
2329         int ret = 0;
2330
2331         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2332                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2333                          transport_wait_for_tasks(cmd);
2334
2335                 ret = transport_release_cmd(cmd);
2336         } else {
2337                 if (wait_for_tasks)
2338                         transport_wait_for_tasks(cmd);
2339                 /*
2340                  * Handle WRITE failure case where transport_generic_new_cmd()
2341                  * has already added se_cmd to state_list, but fabric has
2342                  * failed command before I/O submission.
2343                  */
2344                 if (cmd->state_active) {
2345                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2346                         target_remove_from_state_list(cmd);
2347                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2348                 }
2349
2350                 if (cmd->se_lun)
2351                         transport_lun_remove_cmd(cmd);
2352
2353                 ret = transport_put_cmd(cmd);
2354         }
2355         return ret;
2356 }
2357 EXPORT_SYMBOL(transport_generic_free_cmd);
2358
2359 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2360  * @se_sess:    session to reference
2361  * @se_cmd:     command descriptor to add
2362  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2363  */
2364 int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2365                                bool ack_kref)
2366 {
2367         unsigned long flags;
2368         int ret = 0;
2369
2370         /*
2371          * Add a second kref if the fabric caller is expecting to handle
2372          * fabric acknowledgement that requires two target_put_sess_cmd()
2373          * invocations before se_cmd descriptor release.
2374          */
2375         if (ack_kref) {
2376                 kref_get(&se_cmd->cmd_kref);
2377                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2378         }
2379
2380         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2381         if (se_sess->sess_tearing_down) {
2382                 ret = -ESHUTDOWN;
2383                 goto out;
2384         }
2385         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2386 out:
2387         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2388         return ret;
2389 }
2390 EXPORT_SYMBOL(target_get_sess_cmd);
2391
2392 static void target_release_cmd_kref(struct kref *kref)
2393 {
2394         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2395         struct se_session *se_sess = se_cmd->se_sess;
2396
2397         if (list_empty(&se_cmd->se_cmd_list)) {
2398                 spin_unlock(&se_sess->sess_cmd_lock);
2399                 se_cmd->se_tfo->release_cmd(se_cmd);
2400                 return;
2401         }
2402         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2403                 spin_unlock(&se_sess->sess_cmd_lock);
2404                 complete(&se_cmd->cmd_wait_comp);
2405                 return;
2406         }
2407         list_del(&se_cmd->se_cmd_list);
2408         spin_unlock(&se_sess->sess_cmd_lock);
2409
2410         se_cmd->se_tfo->release_cmd(se_cmd);
2411 }
2412
2413 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2414  * @se_sess:    session to reference
2415  * @se_cmd:     command descriptor to drop
2416  */
2417 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2418 {
2419         if (!se_sess) {
2420                 se_cmd->se_tfo->release_cmd(se_cmd);
2421                 return 1;
2422         }
2423         return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2424                         &se_sess->sess_cmd_lock);
2425 }
2426 EXPORT_SYMBOL(target_put_sess_cmd);
2427
2428 /* target_sess_cmd_list_set_waiting - Flag all commands in
2429  *         sess_cmd_list to complete cmd_wait_comp.  Set
2430  *         sess_tearing_down so no more commands are queued.
2431  * @se_sess:    session to flag
2432  */
2433 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2434 {
2435         struct se_cmd *se_cmd;
2436         unsigned long flags;
2437
2438         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2439         if (se_sess->sess_tearing_down) {
2440                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2441                 return;
2442         }
2443         se_sess->sess_tearing_down = 1;
2444         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2445
2446         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2447                 se_cmd->cmd_wait_set = 1;
2448
2449         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2450 }
2451 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2452
2453 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2454  * @se_sess:    session to wait for active I/O
2455  */
2456 void target_wait_for_sess_cmds(struct se_session *se_sess)
2457 {
2458         struct se_cmd *se_cmd, *tmp_cmd;
2459         unsigned long flags;
2460
2461         list_for_each_entry_safe(se_cmd, tmp_cmd,
2462                                 &se_sess->sess_wait_list, se_cmd_list) {
2463                 list_del(&se_cmd->se_cmd_list);
2464
2465                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2466                         " %d\n", se_cmd, se_cmd->t_state,
2467                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2468
2469                 wait_for_completion(&se_cmd->cmd_wait_comp);
2470                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2471                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2472                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2473
2474                 se_cmd->se_tfo->release_cmd(se_cmd);
2475         }
2476
2477         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2478         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2479         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2480
2481 }
2482 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2483
2484 static int transport_clear_lun_ref_thread(void *p)
2485 {
2486         struct se_lun *lun = p;
2487
2488         percpu_ref_kill(&lun->lun_ref);
2489
2490         wait_for_completion(&lun->lun_ref_comp);
2491         complete(&lun->lun_shutdown_comp);
2492
2493         return 0;
2494 }
2495
2496 int transport_clear_lun_ref(struct se_lun *lun)
2497 {
2498         struct task_struct *kt;
2499
2500         kt = kthread_run(transport_clear_lun_ref_thread, lun,
2501                         "tcm_cl_%u", lun->unpacked_lun);
2502         if (IS_ERR(kt)) {
2503                 pr_err("Unable to start clear_lun thread\n");
2504                 return PTR_ERR(kt);
2505         }
2506         wait_for_completion(&lun->lun_shutdown_comp);
2507
2508         return 0;
2509 }
2510
2511 /**
2512  * transport_wait_for_tasks - wait for completion to occur
2513  * @cmd:        command to wait
2514  *
2515  * Called from frontend fabric context to wait for storage engine
2516  * to pause and/or release frontend generated struct se_cmd.
2517  */
2518 bool transport_wait_for_tasks(struct se_cmd *cmd)
2519 {
2520         unsigned long flags;
2521
2522         spin_lock_irqsave(&cmd->t_state_lock, flags);
2523         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2524             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2525                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2526                 return false;
2527         }
2528
2529         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2530             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2531                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2532                 return false;
2533         }
2534
2535         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2536                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2537                 return false;
2538         }
2539
2540         cmd->transport_state |= CMD_T_STOP;
2541
2542         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2543                 " i_state: %d, t_state: %d, CMD_T_STOP\n",
2544                 cmd, cmd->se_tfo->get_task_tag(cmd),
2545                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2546
2547         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2548
2549         wait_for_completion(&cmd->t_transport_stop_comp);
2550
2551         spin_lock_irqsave(&cmd->t_state_lock, flags);
2552         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2553
2554         pr_debug("wait_for_tasks: Stopped wait_for_completion("
2555                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2556                 cmd->se_tfo->get_task_tag(cmd));
2557
2558         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2559
2560         return true;
2561 }
2562 EXPORT_SYMBOL(transport_wait_for_tasks);
2563
2564 static int transport_get_sense_codes(
2565         struct se_cmd *cmd,
2566         u8 *asc,
2567         u8 *ascq)
2568 {
2569         *asc = cmd->scsi_asc;
2570         *ascq = cmd->scsi_ascq;
2571
2572         return 0;
2573 }
2574
2575 static
2576 void transport_err_sector_info(unsigned char *buffer, sector_t bad_sector)
2577 {
2578         /* Place failed LBA in sense data information descriptor 0. */
2579         buffer[SPC_ADD_SENSE_LEN_OFFSET] = 0xc;
2580         buffer[SPC_DESC_TYPE_OFFSET] = 0; /* Information */
2581         buffer[SPC_ADDITIONAL_DESC_LEN_OFFSET] = 0xa;
2582         buffer[SPC_VALIDITY_OFFSET] = 0x80;
2583
2584         /* Descriptor Information: failing sector */
2585         put_unaligned_be64(bad_sector, &buffer[12]);
2586 }
2587
2588 int
2589 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2590                 sense_reason_t reason, int from_transport)
2591 {
2592         unsigned char *buffer = cmd->sense_buffer;
2593         unsigned long flags;
2594         u8 asc = 0, ascq = 0;
2595
2596         spin_lock_irqsave(&cmd->t_state_lock, flags);
2597         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2598                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2599                 return 0;
2600         }
2601         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2602         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2603
2604         if (!reason && from_transport)
2605                 goto after_reason;
2606
2607         if (!from_transport)
2608                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2609
2610         /*
2611          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2612          * SENSE KEY values from include/scsi/scsi.h
2613          */
2614         switch (reason) {
2615         case TCM_NO_SENSE:
2616                 /* CURRENT ERROR */
2617                 buffer[0] = 0x70;
2618                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2619                 /* Not Ready */
2620                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2621                 /* NO ADDITIONAL SENSE INFORMATION */
2622                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2623                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2624                 break;
2625         case TCM_NON_EXISTENT_LUN:
2626                 /* CURRENT ERROR */
2627                 buffer[0] = 0x70;
2628                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2629                 /* ILLEGAL REQUEST */
2630                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2631                 /* LOGICAL UNIT NOT SUPPORTED */
2632                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2633                 break;
2634         case TCM_UNSUPPORTED_SCSI_OPCODE:
2635         case TCM_SECTOR_COUNT_TOO_MANY:
2636                 /* CURRENT ERROR */
2637                 buffer[0] = 0x70;
2638                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2639                 /* ILLEGAL REQUEST */
2640                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2641                 /* INVALID COMMAND OPERATION CODE */
2642                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2643                 break;
2644         case TCM_UNKNOWN_MODE_PAGE:
2645                 /* CURRENT ERROR */
2646                 buffer[0] = 0x70;
2647                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2648                 /* ILLEGAL REQUEST */
2649                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2650                 /* INVALID FIELD IN CDB */
2651                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2652                 break;
2653         case TCM_CHECK_CONDITION_ABORT_CMD:
2654                 /* CURRENT ERROR */
2655                 buffer[0] = 0x70;
2656                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2657                 /* ABORTED COMMAND */
2658                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2659                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2660                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2661                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2662                 break;
2663         case TCM_INCORRECT_AMOUNT_OF_DATA:
2664                 /* CURRENT ERROR */
2665                 buffer[0] = 0x70;
2666                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2667                 /* ABORTED COMMAND */
2668                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2669                 /* WRITE ERROR */
2670                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2671                 /* NOT ENOUGH UNSOLICITED DATA */
2672                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2673                 break;
2674         case TCM_INVALID_CDB_FIELD:
2675                 /* CURRENT ERROR */
2676                 buffer[0] = 0x70;
2677                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2678                 /* ILLEGAL REQUEST */
2679                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2680                 /* INVALID FIELD IN CDB */
2681                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2682                 break;
2683         case TCM_INVALID_PARAMETER_LIST:
2684                 /* CURRENT ERROR */
2685                 buffer[0] = 0x70;
2686                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2687                 /* ILLEGAL REQUEST */
2688                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2689                 /* INVALID FIELD IN PARAMETER LIST */
2690                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2691                 break;
2692         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2693                 /* CURRENT ERROR */
2694                 buffer[0] = 0x70;
2695                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2696                 /* ILLEGAL REQUEST */
2697                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2698                 /* PARAMETER LIST LENGTH ERROR */
2699                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2700                 break;
2701         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2702                 /* CURRENT ERROR */
2703                 buffer[0] = 0x70;
2704                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2705                 /* ABORTED COMMAND */
2706                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2707                 /* WRITE ERROR */
2708                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2709                 /* UNEXPECTED_UNSOLICITED_DATA */
2710                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2711                 break;
2712         case TCM_SERVICE_CRC_ERROR:
2713                 /* CURRENT ERROR */
2714                 buffer[0] = 0x70;
2715                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2716                 /* ABORTED COMMAND */
2717                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2718                 /* PROTOCOL SERVICE CRC ERROR */
2719                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2720                 /* N/A */
2721                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2722                 break;
2723         case TCM_SNACK_REJECTED:
2724                 /* CURRENT ERROR */
2725                 buffer[0] = 0x70;
2726                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2727                 /* ABORTED COMMAND */
2728                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2729                 /* READ ERROR */
2730                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2731                 /* FAILED RETRANSMISSION REQUEST */
2732                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2733                 break;
2734         case TCM_WRITE_PROTECTED:
2735                 /* CURRENT ERROR */
2736                 buffer[0] = 0x70;
2737                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2738                 /* DATA PROTECT */
2739                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2740                 /* WRITE PROTECTED */
2741                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2742                 break;
2743         case TCM_ADDRESS_OUT_OF_RANGE:
2744                 /* CURRENT ERROR */
2745                 buffer[0] = 0x70;
2746                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2747                 /* ILLEGAL REQUEST */
2748                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2749                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2750                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2751                 break;
2752         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2753                 /* CURRENT ERROR */
2754                 buffer[0] = 0x70;
2755                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2756                 /* UNIT ATTENTION */
2757                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2758                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2759                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2760                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2761                 break;
2762         case TCM_CHECK_CONDITION_NOT_READY:
2763                 /* CURRENT ERROR */
2764                 buffer[0] = 0x70;
2765                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2766                 /* Not Ready */
2767                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2768                 transport_get_sense_codes(cmd, &asc, &ascq);
2769                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2770                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2771                 break;
2772         case TCM_MISCOMPARE_VERIFY:
2773                 /* CURRENT ERROR */
2774                 buffer[0] = 0x70;
2775                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2776                 buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
2777                 /* MISCOMPARE DURING VERIFY OPERATION */
2778                 buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
2779                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
2780                 break;
2781         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
2782                 /* CURRENT ERROR */
2783                 buffer[0] = 0x70;
2784                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2785                 /* ILLEGAL REQUEST */
2786                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2787                 /* LOGICAL BLOCK GUARD CHECK FAILED */
2788                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2789                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x01;
2790                 transport_err_sector_info(buffer, cmd->bad_sector);
2791                 break;
2792         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
2793                 /* CURRENT ERROR */
2794                 buffer[0] = 0x70;
2795                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2796                 /* ILLEGAL REQUEST */
2797                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2798                 /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2799                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2800                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x02;
2801                 transport_err_sector_info(buffer, cmd->bad_sector);
2802                 break;
2803         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
2804                 /* CURRENT ERROR */
2805                 buffer[0] = 0x70;
2806                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2807                 /* ILLEGAL REQUEST */
2808                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2809                 /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2810                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2811                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2812                 transport_err_sector_info(buffer, cmd->bad_sector);
2813                 break;
2814         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2815         default:
2816                 /* CURRENT ERROR */
2817                 buffer[0] = 0x70;
2818                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2819                 /*
2820                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2821                  * Solaris initiators.  Returning NOT READY instead means the
2822                  * operations will be retried a finite number of times and we
2823                  * can survive intermittent errors.
2824                  */
2825                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2826                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2827                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2828                 break;
2829         }
2830         /*
2831          * This code uses linux/include/scsi/scsi.h SAM status codes!
2832          */
2833         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2834         /*
2835          * Automatically padded, this value is encoded in the fabric's
2836          * data_length response PDU containing the SCSI defined sense data.
2837          */
2838         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2839
2840 after_reason:
2841         trace_target_cmd_complete(cmd);
2842         return cmd->se_tfo->queue_status(cmd);
2843 }
2844 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2845
2846 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2847 {
2848         if (!(cmd->transport_state & CMD_T_ABORTED))
2849                 return 0;
2850
2851         /*
2852          * If cmd has been aborted but either no status is to be sent or it has
2853          * already been sent, just return
2854          */
2855         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
2856                 return 1;
2857
2858         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2859                  cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2860
2861         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2862         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2863         trace_target_cmd_complete(cmd);
2864         cmd->se_tfo->queue_status(cmd);
2865
2866         return 1;
2867 }
2868 EXPORT_SYMBOL(transport_check_aborted_status);
2869
2870 void transport_send_task_abort(struct se_cmd *cmd)
2871 {
2872         unsigned long flags;
2873
2874         spin_lock_irqsave(&cmd->t_state_lock, flags);
2875         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2876                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2877                 return;
2878         }
2879         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2880
2881         /*
2882          * If there are still expected incoming fabric WRITEs, we wait
2883          * until until they have completed before sending a TASK_ABORTED
2884          * response.  This response with TASK_ABORTED status will be
2885          * queued back to fabric module by transport_check_aborted_status().
2886          */
2887         if (cmd->data_direction == DMA_TO_DEVICE) {
2888                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2889                         cmd->transport_state |= CMD_T_ABORTED;
2890                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2891                         return;
2892                 }
2893         }
2894         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2895
2896         transport_lun_remove_cmd(cmd);
2897
2898         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2899                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
2900                 cmd->se_tfo->get_task_tag(cmd));
2901
2902         trace_target_cmd_complete(cmd);
2903         cmd->se_tfo->queue_status(cmd);
2904 }
2905
2906 static void target_tmr_work(struct work_struct *work)
2907 {
2908         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2909         struct se_device *dev = cmd->se_dev;
2910         struct se_tmr_req *tmr = cmd->se_tmr_req;
2911         int ret;
2912
2913         switch (tmr->function) {
2914         case TMR_ABORT_TASK:
2915                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2916                 break;
2917         case TMR_ABORT_TASK_SET:
2918         case TMR_CLEAR_ACA:
2919         case TMR_CLEAR_TASK_SET:
2920                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2921                 break;
2922         case TMR_LUN_RESET:
2923                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2924                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2925                                          TMR_FUNCTION_REJECTED;
2926                 break;
2927         case TMR_TARGET_WARM_RESET:
2928                 tmr->response = TMR_FUNCTION_REJECTED;
2929                 break;
2930         case TMR_TARGET_COLD_RESET:
2931                 tmr->response = TMR_FUNCTION_REJECTED;
2932                 break;
2933         default:
2934                 pr_err("Uknown TMR function: 0x%02x.\n",
2935                                 tmr->function);
2936                 tmr->response = TMR_FUNCTION_REJECTED;
2937                 break;
2938         }
2939
2940         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2941         cmd->se_tfo->queue_tm_rsp(cmd);
2942
2943         transport_cmd_check_stop_to_fabric(cmd);
2944 }
2945
2946 int transport_generic_handle_tmr(
2947         struct se_cmd *cmd)
2948 {
2949         unsigned long flags;
2950
2951         spin_lock_irqsave(&cmd->t_state_lock, flags);
2952         cmd->transport_state |= CMD_T_ACTIVE;
2953         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2954
2955         INIT_WORK(&cmd->work, target_tmr_work);
2956         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
2957         return 0;
2958 }
2959 EXPORT_SYMBOL(transport_generic_handle_tmr);