drivers/target/target_core_transport.c

   1 /*******************************************************************************
   2  * Filename:  target_core_transport.c
   3  *
   4  * This file contains the Generic Target Engine Core.
   5  *
   6  * (c) Copyright 2002-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/net.h>
  27 #include <linux/delay.h>
  28 #include <linux/string.h>
  29 #include <linux/timer.h>
  30 #include <linux/slab.h>
  31 #include <linux/blkdev.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/kthread.h>
  34 #include <linux/in.h>
  35 #include <linux/cdrom.h>
  36 #include <linux/module.h>
  37 #include <linux/ratelimit.h>
  38 #include <asm/unaligned.h>
  39 #include <net/sock.h>
  40 #include <net/tcp.h>
  41 #include <scsi/scsi.h>
  42 #include <scsi/scsi_cmnd.h>
  43 #include <scsi/scsi_tcq.h>
  44
  45 #include <target/target_core_base.h>
  46 #include <target/target_core_backend.h>
  47 #include <target/target_core_fabric.h>
  48 #include <target/target_core_configfs.h>
  49
  50 #include "target_core_internal.h"
  51 #include "target_core_alua.h"
  52 #include "target_core_pr.h"
  53 #include "target_core_ua.h"
  54
  55 #define CREATE_TRACE_POINTS
  56 #include <trace/events/target.h>
  57
  58 static struct workqueue_struct *target_completion_wq;
  59 static struct kmem_cache *se_sess_cache;
  60 struct kmem_cache *se_ua_cache;
  61 struct kmem_cache *t10_pr_reg_cache;
  62 struct kmem_cache *t10_alua_lu_gp_cache;
  63 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  64 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  65 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
  66
  67 static void transport_complete_task_attr(struct se_cmd *cmd);
  68 static void transport_handle_queue_full(struct se_cmd *cmd,
  69                 struct se_device *dev);
  70 static int transport_put_cmd(struct se_cmd *cmd);
  71 static void target_complete_ok_work(struct work_struct *work);
  72
  73 int init_se_kmem_caches(void)
  74 {
  75         se_sess_cache = kmem_cache_create("se_sess_cache",
  76                         sizeof(struct se_session), __alignof__(struct se_session),
  77                         0, NULL);
  78         if (!se_sess_cache) {
  79                 pr_err("kmem_cache_create() for struct se_session"
  80                                 " failed\n");
  81                 goto out;
  82         }
  83         se_ua_cache = kmem_cache_create("se_ua_cache",
  84                         sizeof(struct se_ua), __alignof__(struct se_ua),
  85                         0, NULL);
  86         if (!se_ua_cache) {
  87                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  88                 goto out_free_sess_cache;
  89         }
  90         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  91                         sizeof(struct t10_pr_registration),
  92                         __alignof__(struct t10_pr_registration), 0, NULL);
  93         if (!t10_pr_reg_cache) {
  94                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  95                                 " failed\n");
  96                 goto out_free_ua_cache;
  97         }
  98         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
  99                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
 100                         0, NULL);
 101         if (!t10_alua_lu_gp_cache) {
 102                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 103                                 " failed\n");
 104                 goto out_free_pr_reg_cache;
 105         }
 106         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 107                         sizeof(struct t10_alua_lu_gp_member),
 108                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 109         if (!t10_alua_lu_gp_mem_cache) {
 110                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 111                                 "cache failed\n");
 112                 goto out_free_lu_gp_cache;
 113         }
 114         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 115                         sizeof(struct t10_alua_tg_pt_gp),
 116                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 117         if (!t10_alua_tg_pt_gp_cache) {
 118                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 119                                 "cache failed\n");
 120                 goto out_free_lu_gp_mem_cache;
 121         }
 122         t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
 123                         "t10_alua_tg_pt_gp_mem_cache",
 124                         sizeof(struct t10_alua_tg_pt_gp_member),
 125                         __alignof__(struct t10_alua_tg_pt_gp_member),
 126                         0, NULL);
 127         if (!t10_alua_tg_pt_gp_mem_cache) {
 128                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 129                                 "mem_t failed\n");
 130                 goto out_free_tg_pt_gp_cache;
 131         }
 132
 133         target_completion_wq = alloc_workqueue("target_completion",
 134                                                WQ_MEM_RECLAIM, 0);
 135         if (!target_completion_wq)
 136                 goto out_free_tg_pt_gp_mem_cache;
 137
 138         return 0;
 139
 140 out_free_tg_pt_gp_mem_cache:
 141         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 142 out_free_tg_pt_gp_cache:
 143         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 144 out_free_lu_gp_mem_cache:
 145         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 146 out_free_lu_gp_cache:
 147         kmem_cache_destroy(t10_alua_lu_gp_cache);
 148 out_free_pr_reg_cache:
 149         kmem_cache_destroy(t10_pr_reg_cache);
 150 out_free_ua_cache:
 151         kmem_cache_destroy(se_ua_cache);
 152 out_free_sess_cache:
 153         kmem_cache_destroy(se_sess_cache);
 154 out:
 155         return -ENOMEM;
 156 }
 157
 158 void release_se_kmem_caches(void)
 159 {
 160         destroy_workqueue(target_completion_wq);
 161         kmem_cache_destroy(se_sess_cache);
 162         kmem_cache_destroy(se_ua_cache);
 163         kmem_cache_destroy(t10_pr_reg_cache);
 164         kmem_cache_destroy(t10_alua_lu_gp_cache);
 165         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 166         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 167         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 168 }
 169
 170 /* This code ensures unique mib indexes are handed out. */
 171 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 172 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 173
 174 /*
 175  * Allocate a new row index for the entry type specified
 176  */
 177 u32 scsi_get_new_index(scsi_index_t type)
 178 {
 179         u32 new_index;
 180
 181         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 182
 183         spin_lock(&scsi_mib_index_lock);
 184         new_index = ++scsi_mib_index[type];
 185         spin_unlock(&scsi_mib_index_lock);
 186
 187         return new_index;
 188 }
 189
 190 void transport_subsystem_check_init(void)
 191 {
 192         int ret;
 193         static int sub_api_initialized;
 194
 195         if (sub_api_initialized)
 196                 return;
 197
 198         ret = request_module("target_core_iblock");
 199         if (ret != 0)
 200                 pr_err("Unable to load target_core_iblock\n");
 201
 202         ret = request_module("target_core_file");
 203         if (ret != 0)
 204                 pr_err("Unable to load target_core_file\n");
 205
 206         ret = request_module("target_core_pscsi");
 207         if (ret != 0)
 208                 pr_err("Unable to load target_core_pscsi\n");
 209
 210         sub_api_initialized = 1;
 211 }
 212
 213 struct se_session *transport_init_session(void)
 214 {
 215         struct se_session *se_sess;
 216
 217         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 218         if (!se_sess) {
 219                 pr_err("Unable to allocate struct se_session from"
 220                                 " se_sess_cache\n");
 221                 return ERR_PTR(-ENOMEM);
 222         }
 223         INIT_LIST_HEAD(&se_sess->sess_list);
 224         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 225         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 226         INIT_LIST_HEAD(&se_sess->sess_wait_list);
 227         spin_lock_init(&se_sess->sess_cmd_lock);
 228         kref_init(&se_sess->sess_kref);
 229
 230         return se_sess;
 231 }
 232 EXPORT_SYMBOL(transport_init_session);
 233
 234 int transport_alloc_session_tags(struct se_session *se_sess,
 235                                  unsigned int tag_num, unsigned int tag_size)
 236 {
 237         int rc;
 238
 239         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
 240                                         GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
 241         if (!se_sess->sess_cmd_map) {
 242                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
 243                 if (!se_sess->sess_cmd_map) {
 244                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 245                         return -ENOMEM;
 246                 }
 247         }
 248
 249         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
 250         if (rc < 0) {
 251                 pr_err("Unable to init se_sess->sess_tag_pool,"
 252                         " tag_num: %u\n", tag_num);
 253                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 254                         vfree(se_sess->sess_cmd_map);
 255                 else
 256                         kfree(se_sess->sess_cmd_map);
 257                 se_sess->sess_cmd_map = NULL;
 258                 return -ENOMEM;
 259         }
 260
 261         return 0;
 262 }
 263 EXPORT_SYMBOL(transport_alloc_session_tags);
 264
 265 struct se_session *transport_init_session_tags(unsigned int tag_num,
 266                                                unsigned int tag_size)
 267 {
 268         struct se_session *se_sess;
 269         int rc;
 270
 271         se_sess = transport_init_session();
 272         if (IS_ERR(se_sess))
 273                 return se_sess;
 274
 275         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 276         if (rc < 0) {
 277                 transport_free_session(se_sess);
 278                 return ERR_PTR(-ENOMEM);
 279         }
 280
 281         return se_sess;
 282 }
 283 EXPORT_SYMBOL(transport_init_session_tags);
 284
 285 /*
 286  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 287  */
 288 void __transport_register_session(
 289         struct se_portal_group *se_tpg,
 290         struct se_node_acl *se_nacl,
 291         struct se_session *se_sess,
 292         void *fabric_sess_ptr)
 293 {
 294         unsigned char buf[PR_REG_ISID_LEN];
 295
 296         se_sess->se_tpg = se_tpg;
 297         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 298         /*
 299          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 300          *
 301          * Only set for struct se_session's that will actually be moving I/O.
 302          * eg: *NOT* discovery sessions.
 303          */
 304         if (se_nacl) {
 305                 /*
 306                  * If the fabric module supports an ISID based TransportID,
 307                  * save this value in binary from the fabric I_T Nexus now.
 308                  */
 309                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 310                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 311                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 312                                         &buf[0], PR_REG_ISID_LEN);
 313                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 314                 }
 315                 kref_get(&se_nacl->acl_kref);
 316
 317                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 318                 /*
 319                  * The se_nacl->nacl_sess pointer will be set to the
 320                  * last active I_T Nexus for each struct se_node_acl.
 321                  */
 322                 se_nacl->nacl_sess = se_sess;
 323
 324                 list_add_tail(&se_sess->sess_acl_list,
 325                               &se_nacl->acl_sess_list);
 326                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 327         }
 328         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 329
 330         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 331                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 332 }
 333 EXPORT_SYMBOL(__transport_register_session);
 334
 335 void transport_register_session(
 336         struct se_portal_group *se_tpg,
 337         struct se_node_acl *se_nacl,
 338         struct se_session *se_sess,
 339         void *fabric_sess_ptr)
 340 {
 341         unsigned long flags;
 342
 343         spin_lock_irqsave(&se_tpg->session_lock, flags);
 344         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 345         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 346 }
 347 EXPORT_SYMBOL(transport_register_session);
 348
 349 static void target_release_session(struct kref *kref)
 350 {
 351         struct se_session *se_sess = container_of(kref,
 352                         struct se_session, sess_kref);
 353         struct se_portal_group *se_tpg = se_sess->se_tpg;
 354
 355         se_tpg->se_tpg_tfo->close_session(se_sess);
 356 }
 357
 358 void target_get_session(struct se_session *se_sess)
 359 {
 360         kref_get(&se_sess->sess_kref);
 361 }
 362 EXPORT_SYMBOL(target_get_session);
 363
 364 void target_put_session(struct se_session *se_sess)
 365 {
 366         struct se_portal_group *tpg = se_sess->se_tpg;
 367
 368         if (tpg->se_tpg_tfo->put_session != NULL) {
 369                 tpg->se_tpg_tfo->put_session(se_sess);
 370                 return;
 371         }
 372         kref_put(&se_sess->sess_kref, target_release_session);
 373 }
 374 EXPORT_SYMBOL(target_put_session);
 375
 376 static void target_complete_nacl(struct kref *kref)
 377 {
 378         struct se_node_acl *nacl = container_of(kref,
 379                                 struct se_node_acl, acl_kref);
 380
 381         complete(&nacl->acl_free_comp);
 382 }
 383
 384 void target_put_nacl(struct se_node_acl *nacl)
 385 {
 386         kref_put(&nacl->acl_kref, target_complete_nacl);
 387 }
 388
 389 void transport_deregister_session_configfs(struct se_session *se_sess)
 390 {
 391         struct se_node_acl *se_nacl;
 392         unsigned long flags;
 393         /*
 394          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 395          */
 396         se_nacl = se_sess->se_node_acl;
 397         if (se_nacl) {
 398                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 399                 if (se_nacl->acl_stop == 0)
 400                         list_del(&se_sess->sess_acl_list);
 401                 /*
 402                  * If the session list is empty, then clear the pointer.
 403                  * Otherwise, set the struct se_session pointer from the tail
 404                  * element of the per struct se_node_acl active session list.
 405                  */
 406                 if (list_empty(&se_nacl->acl_sess_list))
 407                         se_nacl->nacl_sess = NULL;
 408                 else {
 409                         se_nacl->nacl_sess = container_of(
 410                                         se_nacl->acl_sess_list.prev,
 411                                         struct se_session, sess_acl_list);
 412                 }
 413                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 414         }
 415 }
 416 EXPORT_SYMBOL(transport_deregister_session_configfs);
 417
 418 void transport_free_session(struct se_session *se_sess)
 419 {
 420         if (se_sess->sess_cmd_map) {
 421                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 422                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 423                         vfree(se_sess->sess_cmd_map);
 424                 else
 425                         kfree(se_sess->sess_cmd_map);
 426         }
 427         kmem_cache_free(se_sess_cache, se_sess);
 428 }
 429 EXPORT_SYMBOL(transport_free_session);
 430
 431 void transport_deregister_session(struct se_session *se_sess)
 432 {
 433         struct se_portal_group *se_tpg = se_sess->se_tpg;
 434         struct target_core_fabric_ops *se_tfo;
 435         struct se_node_acl *se_nacl;
 436         unsigned long flags;
 437         bool comp_nacl = true;
 438
 439         if (!se_tpg) {
 440                 transport_free_session(se_sess);
 441                 return;
 442         }
 443         se_tfo = se_tpg->se_tpg_tfo;
 444
 445         spin_lock_irqsave(&se_tpg->session_lock, flags);
 446         list_del(&se_sess->sess_list);
 447         se_sess->se_tpg = NULL;
 448         se_sess->fabric_sess_ptr = NULL;
 449         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 450
 451         /*
 452          * Determine if we need to do extra work for this initiator node's
 453          * struct se_node_acl if it had been previously dynamically generated.
 454          */
 455         se_nacl = se_sess->se_node_acl;
 456
 457         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 458         if (se_nacl && se_nacl->dynamic_node_acl) {
 459                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 460                         list_del(&se_nacl->acl_list);
 461                         se_tpg->num_node_acls--;
 462                         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 463                         core_tpg_wait_for_nacl_pr_ref(se_nacl);
 464                         core_free_device_list_for_node(se_nacl, se_tpg);
 465                         se_tfo->tpg_release_fabric_acl(se_tpg, se_nacl);
 466
 467                         comp_nacl = false;
 468                         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 469                 }
 470         }
 471         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 472
 473         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 474                 se_tpg->se_tpg_tfo->get_fabric_name());
 475         /*
 476          * If last kref is dropping now for an explict NodeACL, awake sleeping
 477          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 478          * removal context.
 479          */
 480         if (se_nacl && comp_nacl == true)
 481                 target_put_nacl(se_nacl);
 482
 483         transport_free_session(se_sess);
 484 }
 485 EXPORT_SYMBOL(transport_deregister_session);
 486
 487 /*
 488  * Called with cmd->t_state_lock held.
 489  */
 490 static void target_remove_from_state_list(struct se_cmd *cmd)
 491 {
 492         struct se_device *dev = cmd->se_dev;
 493         unsigned long flags;
 494
 495         if (!dev)
 496                 return;
 497
 498         if (cmd->transport_state & CMD_T_BUSY)
 499                 return;
 500
 501         spin_lock_irqsave(&dev->execute_task_lock, flags);
 502         if (cmd->state_active) {
 503                 list_del(&cmd->state_list);
 504                 cmd->state_active = false;
 505         }
 506         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 507 }
 508
 509 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 510                                     bool write_pending)
 511 {
 512         unsigned long flags;
 513
 514         spin_lock_irqsave(&cmd->t_state_lock, flags);
 515         if (write_pending)
 516                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 517
 518         /*
 519          * Determine if IOCTL context caller in requesting the stopping of this
 520          * command for LUN shutdown purposes.
 521          */
 522         if (cmd->transport_state & CMD_T_LUN_STOP) {
 523                 pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
 524                         __func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
 525
 526                 cmd->transport_state &= ~CMD_T_ACTIVE;
 527                 if (remove_from_lists)
 528                         target_remove_from_state_list(cmd);
 529                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 530
 531                 complete(&cmd->transport_lun_stop_comp);
 532                 return 1;
 533         }
 534
 535         if (remove_from_lists) {
 536                 target_remove_from_state_list(cmd);
 537
 538                 /*
 539                  * Clear struct se_cmd->se_lun before the handoff to FE.
 540                  */
 541                 cmd->se_lun = NULL;
 542         }
 543
 544         /*
 545          * Determine if frontend context caller is requesting the stopping of
 546          * this command for frontend exceptions.
 547          */
 548         if (cmd->transport_state & CMD_T_STOP) {
 549                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
 550                         __func__, __LINE__,
 551                         cmd->se_tfo->get_task_tag(cmd));
 552
 553                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 554
 555                 complete(&cmd->t_transport_stop_comp);
 556                 return 1;
 557         }
 558
 559         cmd->transport_state &= ~CMD_T_ACTIVE;
 560         if (remove_from_lists) {
 561                 /*
 562                  * Some fabric modules like tcm_loop can release
 563                  * their internally allocated I/O reference now and
 564                  * struct se_cmd now.
 565                  *
 566                  * Fabric modules are expected to return '1' here if the
 567                  * se_cmd being passed is released at this point,
 568                  * or zero if not being released.
 569                  */
 570                 if (cmd->se_tfo->check_stop_free != NULL) {
 571                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 572                         return cmd->se_tfo->check_stop_free(cmd);
 573                 }
 574         }
 575
 576         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 577         return 0;
 578 }
 579
 580 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 581 {
 582         return transport_cmd_check_stop(cmd, true, false);
 583 }
 584
 585 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 586 {
 587         struct se_lun *lun = cmd->se_lun;
 588         unsigned long flags;
 589
 590         if (!lun)
 591                 return;
 592
 593         spin_lock_irqsave(&lun->lun_cmd_lock, flags);
 594         if (!list_empty(&cmd->se_lun_node))
 595                 list_del_init(&cmd->se_lun_node);
 596         spin_unlock_irqrestore(&lun->lun_cmd_lock, flags);
 597 }
 598
 599 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 600 {
 601         if (transport_cmd_check_stop_to_fabric(cmd))
 602                 return;
 603         if (remove)
 604                 transport_put_cmd(cmd);
 605 }
 606
 607 static void target_complete_failure_work(struct work_struct *work)
 608 {
 609         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 610
 611         transport_generic_request_failure(cmd,
 612                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 613 }
 614
 615 /*
 616  * Used when asking transport to copy Sense Data from the underlying
 617  * Linux/SCSI struct scsi_cmnd
 618  */
 619 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 620 {
 621         struct se_device *dev = cmd->se_dev;
 622
 623         WARN_ON(!cmd->se_lun);
 624
 625         if (!dev)
 626                 return NULL;
 627
 628         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 629                 return NULL;
 630
 631         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 632
 633         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 634                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 635         return cmd->sense_buffer;
 636 }
 637
 638 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 639 {
 640         struct se_device *dev = cmd->se_dev;
 641         int success = scsi_status == GOOD;
 642         unsigned long flags;
 643
 644         cmd->scsi_status = scsi_status;
 645
 646
 647         spin_lock_irqsave(&cmd->t_state_lock, flags);
 648         cmd->transport_state &= ~CMD_T_BUSY;
 649
 650         if (dev && dev->transport->transport_complete) {
 651                 dev->transport->transport_complete(cmd,
 652                                 cmd->t_data_sg,
 653                                 transport_get_sense_buffer(cmd));
 654                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 655                         success = 1;
 656         }
 657
 658         /*
 659          * See if we are waiting to complete for an exception condition.
 660          */
 661         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
 662                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 663                 complete(&cmd->task_stop_comp);
 664                 return;
 665         }
 666
 667         if (!success)
 668                 cmd->transport_state |= CMD_T_FAILED;
 669
 670         /*
 671          * Check for case where an explict ABORT_TASK has been received
 672          * and transport_wait_for_tasks() will be waiting for completion..
 673          */
 674         if (cmd->transport_state & CMD_T_ABORTED &&
 675             cmd->transport_state & CMD_T_STOP) {
 676                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 677                 complete(&cmd->t_transport_stop_comp);
 678                 return;
 679         } else if (cmd->transport_state & CMD_T_FAILED) {
 680                 INIT_WORK(&cmd->work, target_complete_failure_work);
 681         } else {
 682                 INIT_WORK(&cmd->work, target_complete_ok_work);
 683         }
 684
 685         cmd->t_state = TRANSPORT_COMPLETE;
 686         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 687         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 688
 689         queue_work(target_completion_wq, &cmd->work);
 690 }
 691 EXPORT_SYMBOL(target_complete_cmd);
 692
 693 static void target_add_to_state_list(struct se_cmd *cmd)
 694 {
 695         struct se_device *dev = cmd->se_dev;
 696         unsigned long flags;
 697
 698         spin_lock_irqsave(&dev->execute_task_lock, flags);
 699         if (!cmd->state_active) {
 700                 list_add_tail(&cmd->state_list, &dev->state_list);
 701                 cmd->state_active = true;
 702         }
 703         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 704 }
 705
 706 /*
 707  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 708  */
 709 static void transport_write_pending_qf(struct se_cmd *cmd);
 710 static void transport_complete_qf(struct se_cmd *cmd);
 711
 712 void target_qf_do_work(struct work_struct *work)
 713 {
 714         struct se_device *dev = container_of(work, struct se_device,
 715                                         qf_work_queue);
 716         LIST_HEAD(qf_cmd_list);
 717         struct se_cmd *cmd, *cmd_tmp;
 718
 719         spin_lock_irq(&dev->qf_cmd_lock);
 720         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 721         spin_unlock_irq(&dev->qf_cmd_lock);
 722
 723         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 724                 list_del(&cmd->se_qf_node);
 725                 atomic_dec(&dev->dev_qf_count);
 726                 smp_mb__after_atomic_dec();
 727
 728                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 729                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 730                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 731                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 732                         : "UNKNOWN");
 733
 734                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 735                         transport_write_pending_qf(cmd);
 736                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 737                         transport_complete_qf(cmd);
 738         }
 739 }
 740
 741 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 742 {
 743         switch (cmd->data_direction) {
 744         case DMA_NONE:
 745                 return "NONE";
 746         case DMA_FROM_DEVICE:
 747                 return "READ";
 748         case DMA_TO_DEVICE:
 749                 return "WRITE";
 750         case DMA_BIDIRECTIONAL:
 751                 return "BIDI";
 752         default:
 753                 break;
 754         }
 755
 756         return "UNKNOWN";
 757 }
 758
 759 void transport_dump_dev_state(
 760         struct se_device *dev,
 761         char *b,
 762         int *bl)
 763 {
 764         *bl += sprintf(b + *bl, "Status: ");
 765         if (dev->export_count)
 766                 *bl += sprintf(b + *bl, "ACTIVATED");
 767         else
 768                 *bl += sprintf(b + *bl, "DEACTIVATED");
 769
 770         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 771         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 772                 dev->dev_attrib.block_size,
 773                 dev->dev_attrib.hw_max_sectors);
 774         *bl += sprintf(b + *bl, "        ");
 775 }
 776
 777 void transport_dump_vpd_proto_id(
 778         struct t10_vpd *vpd,
 779         unsigned char *p_buf,
 780         int p_buf_len)
 781 {
 782         unsigned char buf[VPD_TMP_BUF_SIZE];
 783         int len;
 784
 785         memset(buf, 0, VPD_TMP_BUF_SIZE);
 786         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 787
 788         switch (vpd->protocol_identifier) {
 789         case 0x00:
 790                 sprintf(buf+len, "Fibre Channel\n");
 791                 break;
 792         case 0x10:
 793                 sprintf(buf+len, "Parallel SCSI\n");
 794                 break;
 795         case 0x20:
 796                 sprintf(buf+len, "SSA\n");
 797                 break;
 798         case 0x30:
 799                 sprintf(buf+len, "IEEE 1394\n");
 800                 break;
 801         case 0x40:
 802                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 803                                 " Protocol\n");
 804                 break;
 805         case 0x50:
 806                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 807                 break;
 808         case 0x60:
 809                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 810                 break;
 811         case 0x70:
 812                 sprintf(buf+len, "Automation/Drive Interface Transport"
 813                                 " Protocol\n");
 814                 break;
 815         case 0x80:
 816                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 817                 break;
 818         default:
 819                 sprintf(buf+len, "Unknown 0x%02x\n",
 820                                 vpd->protocol_identifier);
 821                 break;
 822         }
 823
 824         if (p_buf)
 825                 strncpy(p_buf, buf, p_buf_len);
 826         else
 827                 pr_debug("%s", buf);
 828 }
 829
 830 void
 831 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 832 {
 833         /*
 834          * Check if the Protocol Identifier Valid (PIV) bit is set..
 835          *
 836          * from spc3r23.pdf section 7.5.1
 837          */
 838          if (page_83[1] & 0x80) {
 839                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 840                 vpd->protocol_identifier_set = 1;
 841                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 842         }
 843 }
 844 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 845
 846 int transport_dump_vpd_assoc(
 847         struct t10_vpd *vpd,
 848         unsigned char *p_buf,
 849         int p_buf_len)
 850 {
 851         unsigned char buf[VPD_TMP_BUF_SIZE];
 852         int ret = 0;
 853         int len;
 854
 855         memset(buf, 0, VPD_TMP_BUF_SIZE);
 856         len = sprintf(buf, "T10 VPD Identifier Association: ");
 857
 858         switch (vpd->association) {
 859         case 0x00:
 860                 sprintf(buf+len, "addressed logical unit\n");
 861                 break;
 862         case 0x10:
 863                 sprintf(buf+len, "target port\n");
 864                 break;
 865         case 0x20:
 866                 sprintf(buf+len, "SCSI target device\n");
 867                 break;
 868         default:
 869                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 870                 ret = -EINVAL;
 871                 break;
 872         }
 873
 874         if (p_buf)
 875                 strncpy(p_buf, buf, p_buf_len);
 876         else
 877                 pr_debug("%s", buf);
 878
 879         return ret;
 880 }
 881
 882 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 883 {
 884         /*
 885          * The VPD identification association..
 886          *
 887          * from spc3r23.pdf Section 7.6.3.1 Table 297
 888          */
 889         vpd->association = (page_83[1] & 0x30);
 890         return transport_dump_vpd_assoc(vpd, NULL, 0);
 891 }
 892 EXPORT_SYMBOL(transport_set_vpd_assoc);
 893
 894 int transport_dump_vpd_ident_type(
 895         struct t10_vpd *vpd,
 896         unsigned char *p_buf,
 897         int p_buf_len)
 898 {
 899         unsigned char buf[VPD_TMP_BUF_SIZE];
 900         int ret = 0;
 901         int len;
 902
 903         memset(buf, 0, VPD_TMP_BUF_SIZE);
 904         len = sprintf(buf, "T10 VPD Identifier Type: ");
 905
 906         switch (vpd->device_identifier_type) {
 907         case 0x00:
 908                 sprintf(buf+len, "Vendor specific\n");
 909                 break;
 910         case 0x01:
 911                 sprintf(buf+len, "T10 Vendor ID based\n");
 912                 break;
 913         case 0x02:
 914                 sprintf(buf+len, "EUI-64 based\n");
 915                 break;
 916         case 0x03:
 917                 sprintf(buf+len, "NAA\n");
 918                 break;
 919         case 0x04:
 920                 sprintf(buf+len, "Relative target port identifier\n");
 921                 break;
 922         case 0x08:
 923                 sprintf(buf+len, "SCSI name string\n");
 924                 break;
 925         default:
 926                 sprintf(buf+len, "Unsupported: 0x%02x\n",
 927                                 vpd->device_identifier_type);
 928                 ret = -EINVAL;
 929                 break;
 930         }
 931
 932         if (p_buf) {
 933                 if (p_buf_len < strlen(buf)+1)
 934                         return -EINVAL;
 935                 strncpy(p_buf, buf, p_buf_len);
 936         } else {
 937                 pr_debug("%s", buf);
 938         }
 939
 940         return ret;
 941 }
 942
 943 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
 944 {
 945         /*
 946          * The VPD identifier type..
 947          *
 948          * from spc3r23.pdf Section 7.6.3.1 Table 298
 949          */
 950         vpd->device_identifier_type = (page_83[1] & 0x0f);
 951         return transport_dump_vpd_ident_type(vpd, NULL, 0);
 952 }
 953 EXPORT_SYMBOL(transport_set_vpd_ident_type);
 954
 955 int transport_dump_vpd_ident(
 956         struct t10_vpd *vpd,
 957         unsigned char *p_buf,
 958         int p_buf_len)
 959 {
 960         unsigned char buf[VPD_TMP_BUF_SIZE];
 961         int ret = 0;
 962
 963         memset(buf, 0, VPD_TMP_BUF_SIZE);
 964
 965         switch (vpd->device_identifier_code_set) {
 966         case 0x01: /* Binary */
 967                 snprintf(buf, sizeof(buf),
 968                         "T10 VPD Binary Device Identifier: %s\n",
 969                         &vpd->device_identifier[0]);
 970                 break;
 971         case 0x02: /* ASCII */
 972                 snprintf(buf, sizeof(buf),
 973                         "T10 VPD ASCII Device Identifier: %s\n",
 974                         &vpd->device_identifier[0]);
 975                 break;
 976         case 0x03: /* UTF-8 */
 977                 snprintf(buf, sizeof(buf),
 978                         "T10 VPD UTF-8 Device Identifier: %s\n",
 979                         &vpd->device_identifier[0]);
 980                 break;
 981         default:
 982                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
 983                         " 0x%02x", vpd->device_identifier_code_set);
 984                 ret = -EINVAL;
 985                 break;
 986         }
 987
 988         if (p_buf)
 989                 strncpy(p_buf, buf, p_buf_len);
 990         else
 991                 pr_debug("%s", buf);
 992
 993         return ret;
 994 }
 995
 996 int
 997 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
 998 {
 999         static const char hex_str[] = "0123456789abcdef";
1000         int j = 0, i = 4; /* offset to start of the identifier */
1001
1002         /*
1003          * The VPD Code Set (encoding)
1004          *
1005          * from spc3r23.pdf Section 7.6.3.1 Table 296
1006          */
1007         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1008         switch (vpd->device_identifier_code_set) {
1009         case 0x01: /* Binary */
1010                 vpd->device_identifier[j++] =
1011                                 hex_str[vpd->device_identifier_type];
1012                 while (i < (4 + page_83[3])) {
1013                         vpd->device_identifier[j++] =
1014                                 hex_str[(page_83[i] & 0xf0) >> 4];
1015                         vpd->device_identifier[j++] =
1016                                 hex_str[page_83[i] & 0x0f];
1017                         i++;
1018                 }
1019                 break;
1020         case 0x02: /* ASCII */
1021         case 0x03: /* UTF-8 */
1022                 while (i < (4 + page_83[3]))
1023                         vpd->device_identifier[j++] = page_83[i++];
1024                 break;
1025         default:
1026                 break;
1027         }
1028
1029         return transport_dump_vpd_ident(vpd, NULL, 0);
1030 }
1031 EXPORT_SYMBOL(transport_set_vpd_ident);
1032
1033 sense_reason_t
1034 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1035 {
1036         struct se_device *dev = cmd->se_dev;
1037
1038         if (cmd->unknown_data_length) {
1039                 cmd->data_length = size;
1040         } else if (size != cmd->data_length) {
1041                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1042                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1043                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1044                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1045
1046                 if (cmd->data_direction == DMA_TO_DEVICE) {
1047                         pr_err("Rejecting underflow/overflow"
1048                                         " WRITE data\n");
1049                         return TCM_INVALID_CDB_FIELD;
1050                 }
1051                 /*
1052                  * Reject READ_* or WRITE_* with overflow/underflow for
1053                  * type SCF_SCSI_DATA_CDB.
1054                  */
1055                 if (dev->dev_attrib.block_size != 512)  {
1056                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1057                                 " CDB on non 512-byte sector setup subsystem"
1058                                 " plugin: %s\n", dev->transport->name);
1059                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1060                         return TCM_INVALID_CDB_FIELD;
1061                 }
1062                 /*
1063                  * For the overflow case keep the existing fabric provided
1064                  * ->data_length.  Otherwise for the underflow case, reset
1065                  * ->data_length to the smaller SCSI expected data transfer
1066                  * length.
1067                  */
1068                 if (size > cmd->data_length) {
1069                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1070                         cmd->residual_count = (size - cmd->data_length);
1071                 } else {
1072                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1073                         cmd->residual_count = (cmd->data_length - size);
1074                         cmd->data_length = size;
1075                 }
1076         }
1077
1078         return 0;
1079
1080 }
1081
1082 /*
1083  * Used by fabric modules containing a local struct se_cmd within their
1084  * fabric dependent per I/O descriptor.
1085  */
1086 void transport_init_se_cmd(
1087         struct se_cmd *cmd,
1088         struct target_core_fabric_ops *tfo,
1089         struct se_session *se_sess,
1090         u32 data_length,
1091         int data_direction,
1092         int task_attr,
1093         unsigned char *sense_buffer)
1094 {
1095         INIT_LIST_HEAD(&cmd->se_lun_node);
1096         INIT_LIST_HEAD(&cmd->se_delayed_node);
1097         INIT_LIST_HEAD(&cmd->se_qf_node);
1098         INIT_LIST_HEAD(&cmd->se_cmd_list);
1099         INIT_LIST_HEAD(&cmd->state_list);
1100         init_completion(&cmd->transport_lun_fe_stop_comp);
1101         init_completion(&cmd->transport_lun_stop_comp);
1102         init_completion(&cmd->t_transport_stop_comp);
1103         init_completion(&cmd->cmd_wait_comp);
1104         init_completion(&cmd->task_stop_comp);
1105         spin_lock_init(&cmd->t_state_lock);
1106         cmd->transport_state = CMD_T_DEV_ACTIVE;
1107
1108         cmd->se_tfo = tfo;
1109         cmd->se_sess = se_sess;
1110         cmd->data_length = data_length;
1111         cmd->data_direction = data_direction;
1112         cmd->sam_task_attr = task_attr;
1113         cmd->sense_buffer = sense_buffer;
1114
1115         cmd->state_active = false;
1116 }
1117 EXPORT_SYMBOL(transport_init_se_cmd);
1118
1119 static sense_reason_t
1120 transport_check_alloc_task_attr(struct se_cmd *cmd)
1121 {
1122         struct se_device *dev = cmd->se_dev;
1123
1124         /*
1125          * Check if SAM Task Attribute emulation is enabled for this
1126          * struct se_device storage object
1127          */
1128         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1129                 return 0;
1130
1131         if (cmd->sam_task_attr == MSG_ACA_TAG) {
1132                 pr_debug("SAM Task Attribute ACA"
1133                         " emulation is not supported\n");
1134                 return TCM_INVALID_CDB_FIELD;
1135         }
1136         /*
1137          * Used to determine when ORDERED commands should go from
1138          * Dormant to Active status.
1139          */
1140         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1141         smp_mb__after_atomic_inc();
1142         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1143                         cmd->se_ordered_id, cmd->sam_task_attr,
1144                         dev->transport->name);
1145         return 0;
1146 }
1147
1148 sense_reason_t
1149 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1150 {
1151         struct se_device *dev = cmd->se_dev;
1152         sense_reason_t ret;
1153
1154         /*
1155          * Ensure that the received CDB is less than the max (252 + 8) bytes
1156          * for VARIABLE_LENGTH_CMD
1157          */
1158         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1159                 pr_err("Received SCSI CDB with command_size: %d that"
1160                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1161                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1162                 return TCM_INVALID_CDB_FIELD;
1163         }
1164         /*
1165          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1166          * allocate the additional extended CDB buffer now..  Otherwise
1167          * setup the pointer from __t_task_cdb to t_task_cdb.
1168          */
1169         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1170                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1171                                                 GFP_KERNEL);
1172                 if (!cmd->t_task_cdb) {
1173                         pr_err("Unable to allocate cmd->t_task_cdb"
1174                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1175                                 scsi_command_size(cdb),
1176                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1177                         return TCM_OUT_OF_RESOURCES;
1178                 }
1179         } else
1180                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1181         /*
1182          * Copy the original CDB into cmd->
1183          */
1184         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1185
1186         trace_target_sequencer_start(cmd);
1187
1188         /*
1189          * Check for an existing UNIT ATTENTION condition
1190          */
1191         ret = target_scsi3_ua_check(cmd);
1192         if (ret)
1193                 return ret;
1194
1195         ret = target_alua_state_check(cmd);
1196         if (ret)
1197                 return ret;
1198
1199         ret = target_check_reservation(cmd);
1200         if (ret) {
1201                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1202                 return ret;
1203         }
1204
1205         ret = dev->transport->parse_cdb(cmd);
1206         if (ret)
1207                 return ret;
1208
1209         ret = transport_check_alloc_task_attr(cmd);
1210         if (ret)
1211                 return ret;
1212
1213         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1214
1215         spin_lock(&cmd->se_lun->lun_sep_lock);
1216         if (cmd->se_lun->lun_sep)
1217                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1218         spin_unlock(&cmd->se_lun->lun_sep_lock);
1219         return 0;
1220 }
1221 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1222
1223 /*
1224  * Used by fabric module frontends to queue tasks directly.
1225  * Many only be used from process context only
1226  */
1227 int transport_handle_cdb_direct(
1228         struct se_cmd *cmd)
1229 {
1230         sense_reason_t ret;
1231
1232         if (!cmd->se_lun) {
1233                 dump_stack();
1234                 pr_err("cmd->se_lun is NULL\n");
1235                 return -EINVAL;
1236         }
1237         if (in_interrupt()) {
1238                 dump_stack();
1239                 pr_err("transport_generic_handle_cdb cannot be called"
1240                                 " from interrupt context\n");
1241                 return -EINVAL;
1242         }
1243         /*
1244          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1245          * outstanding descriptors are handled correctly during shutdown via
1246          * transport_wait_for_tasks()
1247          *
1248          * Also, we don't take cmd->t_state_lock here as we only expect
1249          * this to be called for initial descriptor submission.
1250          */
1251         cmd->t_state = TRANSPORT_NEW_CMD;
1252         cmd->transport_state |= CMD_T_ACTIVE;
1253
1254         /*
1255          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1256          * so follow TRANSPORT_NEW_CMD processing thread context usage
1257          * and call transport_generic_request_failure() if necessary..
1258          */
1259         ret = transport_generic_new_cmd(cmd);
1260         if (ret)
1261                 transport_generic_request_failure(cmd, ret);
1262         return 0;
1263 }
1264 EXPORT_SYMBOL(transport_handle_cdb_direct);
1265
1266 sense_reason_t
1267 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1268                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1269 {
1270         if (!sgl || !sgl_count)
1271                 return 0;
1272
1273         /*
1274          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1275          * scatterlists already have been set to follow what the fabric
1276          * passes for the original expected data transfer length.
1277          */
1278         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1279                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1280                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1281                 return TCM_INVALID_CDB_FIELD;
1282         }
1283
1284         cmd->t_data_sg = sgl;
1285         cmd->t_data_nents = sgl_count;
1286
1287         if (sgl_bidi && sgl_bidi_count) {
1288                 cmd->t_bidi_data_sg = sgl_bidi;
1289                 cmd->t_bidi_data_nents = sgl_bidi_count;
1290         }
1291         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1292         return 0;
1293 }
1294
1295 /*
1296  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1297  *                       se_cmd + use pre-allocated SGL memory.
1298  *
1299  * @se_cmd: command descriptor to submit
1300  * @se_sess: associated se_sess for endpoint
1301  * @cdb: pointer to SCSI CDB
1302  * @sense: pointer to SCSI sense buffer
1303  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1304  * @data_length: fabric expected data transfer length
1305  * @task_addr: SAM task attribute
1306  * @data_dir: DMA data direction
1307  * @flags: flags for command submission from target_sc_flags_tables
1308  * @sgl: struct scatterlist memory for unidirectional mapping
1309  * @sgl_count: scatterlist count for unidirectional mapping
1310  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1311  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1312  *
1313  * Returns non zero to signal active I/O shutdown failure.  All other
1314  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1315  * but still return zero here.
1316  *
1317  * This may only be called from process context, and also currently
1318  * assumes internal allocation of fabric payload buffer by target-core.
1319  */
1320 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1321                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1322                 u32 data_length, int task_attr, int data_dir, int flags,
1323                 struct scatterlist *sgl, u32 sgl_count,
1324                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1325 {
1326         struct se_portal_group *se_tpg;
1327         sense_reason_t rc;
1328         int ret;
1329
1330         se_tpg = se_sess->se_tpg;
1331         BUG_ON(!se_tpg);
1332         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1333         BUG_ON(in_interrupt());
1334         /*
1335          * Initialize se_cmd for target operation.  From this point
1336          * exceptions are handled by sending exception status via
1337          * target_core_fabric_ops->queue_status() callback
1338          */
1339         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1340                                 data_length, data_dir, task_attr, sense);
1341         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1342                 se_cmd->unknown_data_length = 1;
1343         /*
1344          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1345          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1346          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1347          * kref_put() to happen during fabric packet acknowledgement.
1348          */
1349         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1350         if (ret)
1351                 return ret;
1352         /*
1353          * Signal bidirectional data payloads to target-core
1354          */
1355         if (flags & TARGET_SCF_BIDI_OP)
1356                 se_cmd->se_cmd_flags |= SCF_BIDI;
1357         /*
1358          * Locate se_lun pointer and attach it to struct se_cmd
1359          */
1360         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1361         if (rc) {
1362                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1363                 target_put_sess_cmd(se_sess, se_cmd);
1364                 return 0;
1365         }
1366
1367         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1368         if (rc != 0) {
1369                 transport_generic_request_failure(se_cmd, rc);
1370                 return 0;
1371         }
1372         /*
1373          * When a non zero sgl_count has been passed perform SGL passthrough
1374          * mapping for pre-allocated fabric memory instead of having target
1375          * core perform an internal SGL allocation..
1376          */
1377         if (sgl_count != 0) {
1378                 BUG_ON(!sgl);
1379
1380                 /*
1381                  * A work-around for tcm_loop as some userspace code via
1382                  * scsi-generic do not memset their associated read buffers,
1383                  * so go ahead and do that here for type non-data CDBs.  Also
1384                  * note that this is currently guaranteed to be a single SGL
1385                  * for this case by target core in target_setup_cmd_from_cdb()
1386                  * -> transport_generic_cmd_sequencer().
1387                  */
1388                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1389                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1390                         unsigned char *buf = NULL;
1391
1392                         if (sgl)
1393                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1394
1395                         if (buf) {
1396                                 memset(buf, 0, sgl->length);
1397                                 kunmap(sg_page(sgl));
1398                         }
1399                 }
1400
1401                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1402                                 sgl_bidi, sgl_bidi_count);
1403                 if (rc != 0) {
1404                         transport_generic_request_failure(se_cmd, rc);
1405                         return 0;
1406                 }
1407         }
1408         /*
1409          * Check if we need to delay processing because of ALUA
1410          * Active/NonOptimized primary access state..
1411          */
1412         core_alua_check_nonop_delay(se_cmd);
1413
1414         transport_handle_cdb_direct(se_cmd);
1415         return 0;
1416 }
1417 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1418
1419 /*
1420  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1421  *
1422  * @se_cmd: command descriptor to submit
1423  * @se_sess: associated se_sess for endpoint
1424  * @cdb: pointer to SCSI CDB
1425  * @sense: pointer to SCSI sense buffer
1426  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1427  * @data_length: fabric expected data transfer length
1428  * @task_addr: SAM task attribute
1429  * @data_dir: DMA data direction
1430  * @flags: flags for command submission from target_sc_flags_tables
1431  *
1432  * Returns non zero to signal active I/O shutdown failure.  All other
1433  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1434  * but still return zero here.
1435  *
1436  * This may only be called from process context, and also currently
1437  * assumes internal allocation of fabric payload buffer by target-core.
1438  *
1439  * It also assumes interal target core SGL memory allocation.
1440  */
1441 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1442                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1443                 u32 data_length, int task_attr, int data_dir, int flags)
1444 {
1445         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1446                         unpacked_lun, data_length, task_attr, data_dir,
1447                         flags, NULL, 0, NULL, 0);
1448 }
1449 EXPORT_SYMBOL(target_submit_cmd);
1450
1451 static void target_complete_tmr_failure(struct work_struct *work)
1452 {
1453         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1454
1455         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1456         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1457
1458         transport_cmd_check_stop_to_fabric(se_cmd);
1459 }
1460
1461 /**
1462  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1463  *                     for TMR CDBs
1464  *
1465  * @se_cmd: command descriptor to submit
1466  * @se_sess: associated se_sess for endpoint
1467  * @sense: pointer to SCSI sense buffer
1468  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1469  * @fabric_context: fabric context for TMR req
1470  * @tm_type: Type of TM request
1471  * @gfp: gfp type for caller
1472  * @tag: referenced task tag for TMR_ABORT_TASK
1473  * @flags: submit cmd flags
1474  *
1475  * Callable from all contexts.
1476  **/
1477
1478 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1479                 unsigned char *sense, u32 unpacked_lun,
1480                 void *fabric_tmr_ptr, unsigned char tm_type,
1481                 gfp_t gfp, unsigned int tag, int flags)
1482 {
1483         struct se_portal_group *se_tpg;
1484         int ret;
1485
1486         se_tpg = se_sess->se_tpg;
1487         BUG_ON(!se_tpg);
1488
1489         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1490                               0, DMA_NONE, MSG_SIMPLE_TAG, sense);
1491         /*
1492          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1493          * allocation failure.
1494          */
1495         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1496         if (ret < 0)
1497                 return -ENOMEM;
1498
1499         if (tm_type == TMR_ABORT_TASK)
1500                 se_cmd->se_tmr_req->ref_task_tag = tag;
1501
1502         /* See target_submit_cmd for commentary */
1503         ret = target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF));
1504         if (ret) {
1505                 core_tmr_release_req(se_cmd->se_tmr_req);
1506                 return ret;
1507         }
1508
1509         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1510         if (ret) {
1511                 /*
1512                  * For callback during failure handling, push this work off
1513                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1514                  */
1515                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1516                 schedule_work(&se_cmd->work);
1517                 return 0;
1518         }
1519         transport_generic_handle_tmr(se_cmd);
1520         return 0;
1521 }
1522 EXPORT_SYMBOL(target_submit_tmr);
1523
1524 /*
1525  * If the cmd is active, request it to be stopped and sleep until it
1526  * has completed.
1527  */
1528 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1529 {
1530         bool was_active = false;
1531
1532         if (cmd->transport_state & CMD_T_BUSY) {
1533                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1534                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1535
1536                 pr_debug("cmd %p waiting to complete\n", cmd);
1537                 wait_for_completion(&cmd->task_stop_comp);
1538                 pr_debug("cmd %p stopped successfully\n", cmd);
1539
1540                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1541                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1542                 cmd->transport_state &= ~CMD_T_BUSY;
1543                 was_active = true;
1544         }
1545
1546         return was_active;
1547 }
1548
1549 /*
1550  * Handle SAM-esque emulation for generic transport request failures.
1551  */
1552 void transport_generic_request_failure(struct se_cmd *cmd,
1553                 sense_reason_t sense_reason)
1554 {
1555         int ret = 0;
1556
1557         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1558                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1559                 cmd->t_task_cdb[0]);
1560         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1561                 cmd->se_tfo->get_cmd_state(cmd),
1562                 cmd->t_state, sense_reason);
1563         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1564                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1565                 (cmd->transport_state & CMD_T_STOP) != 0,
1566                 (cmd->transport_state & CMD_T_SENT) != 0);
1567
1568         /*
1569          * For SAM Task Attribute emulation for failed struct se_cmd
1570          */
1571         transport_complete_task_attr(cmd);
1572         /*
1573          * Handle special case for COMPARE_AND_WRITE failure, where the
1574          * callback is expected to drop the per device ->caw_mutex.
1575          */
1576         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1577              cmd->transport_complete_callback)
1578                 cmd->transport_complete_callback(cmd);
1579
1580         switch (sense_reason) {
1581         case TCM_NON_EXISTENT_LUN:
1582         case TCM_UNSUPPORTED_SCSI_OPCODE:
1583         case TCM_INVALID_CDB_FIELD:
1584         case TCM_INVALID_PARAMETER_LIST:
1585         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1586         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1587         case TCM_UNKNOWN_MODE_PAGE:
1588         case TCM_WRITE_PROTECTED:
1589         case TCM_ADDRESS_OUT_OF_RANGE:
1590         case TCM_CHECK_CONDITION_ABORT_CMD:
1591         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1592         case TCM_CHECK_CONDITION_NOT_READY:
1593                 break;
1594         case TCM_OUT_OF_RESOURCES:
1595                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1596                 break;
1597         case TCM_RESERVATION_CONFLICT:
1598                 /*
1599                  * No SENSE Data payload for this case, set SCSI Status
1600                  * and queue the response to $FABRIC_MOD.
1601                  *
1602                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1603                  */
1604                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1605                 /*
1606                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1607                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1608                  * CONFLICT STATUS.
1609                  *
1610                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1611                  */
1612                 if (cmd->se_sess &&
1613                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1614                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1615                                 cmd->orig_fe_lun, 0x2C,
1616                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1617
1618                 trace_target_cmd_complete(cmd);
1619                 ret = cmd->se_tfo-> queue_status(cmd);
1620                 if (ret == -EAGAIN || ret == -ENOMEM)
1621                         goto queue_full;
1622                 goto check_stop;
1623         default:
1624                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1625                         cmd->t_task_cdb[0], sense_reason);
1626                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1627                 break;
1628         }
1629
1630         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1631         if (ret == -EAGAIN || ret == -ENOMEM)
1632                 goto queue_full;
1633
1634 check_stop:
1635         transport_lun_remove_cmd(cmd);
1636         if (!transport_cmd_check_stop_to_fabric(cmd))
1637                 ;
1638         return;
1639
1640 queue_full:
1641         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1642         transport_handle_queue_full(cmd, cmd->se_dev);
1643 }
1644 EXPORT_SYMBOL(transport_generic_request_failure);
1645
1646 void __target_execute_cmd(struct se_cmd *cmd)
1647 {
1648         sense_reason_t ret;
1649
1650         if (cmd->execute_cmd) {
1651                 ret = cmd->execute_cmd(cmd);
1652                 if (ret) {
1653                         spin_lock_irq(&cmd->t_state_lock);
1654                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1655                         spin_unlock_irq(&cmd->t_state_lock);
1656
1657                         transport_generic_request_failure(cmd, ret);
1658                 }
1659         }
1660 }
1661
1662 static bool target_handle_task_attr(struct se_cmd *cmd)
1663 {
1664         struct se_device *dev = cmd->se_dev;
1665
1666         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1667                 return false;
1668
1669         /*
1670          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1671          * to allow the passed struct se_cmd list of tasks to the front of the list.
1672          */
1673         switch (cmd->sam_task_attr) {
1674         case MSG_HEAD_TAG:
1675                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1676                          "se_ordered_id: %u\n",
1677                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1678                 return false;
1679         case MSG_ORDERED_TAG:
1680                 atomic_inc(&dev->dev_ordered_sync);
1681                 smp_mb__after_atomic_inc();
1682
1683                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1684                          " se_ordered_id: %u\n",
1685                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1686
1687                 /*
1688                  * Execute an ORDERED command if no other older commands
1689                  * exist that need to be completed first.
1690                  */
1691                 if (!atomic_read(&dev->simple_cmds))
1692                         return false;
1693                 break;
1694         default:
1695                 /*
1696                  * For SIMPLE and UNTAGGED Task Attribute commands
1697                  */
1698                 atomic_inc(&dev->simple_cmds);
1699                 smp_mb__after_atomic_inc();
1700                 break;
1701         }
1702
1703         if (atomic_read(&dev->dev_ordered_sync) == 0)
1704                 return false;
1705
1706         spin_lock(&dev->delayed_cmd_lock);
1707         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1708         spin_unlock(&dev->delayed_cmd_lock);
1709
1710         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1711                 " delayed CMD list, se_ordered_id: %u\n",
1712                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1713                 cmd->se_ordered_id);
1714         return true;
1715 }
1716
1717 void target_execute_cmd(struct se_cmd *cmd)
1718 {
1719         /*
1720          * If the received CDB has aleady been aborted stop processing it here.
1721          */
1722         if (transport_check_aborted_status(cmd, 1)) {
1723                 complete(&cmd->transport_lun_stop_comp);
1724                 return;
1725         }
1726
1727         /*
1728          * Determine if IOCTL context caller in requesting the stopping of this
1729          * command for LUN shutdown purposes.
1730          */
1731         spin_lock_irq(&cmd->t_state_lock);
1732         if (cmd->transport_state & CMD_T_LUN_STOP) {
1733                 pr_debug("%s:%d CMD_T_LUN_STOP for ITT: 0x%08x\n",
1734                         __func__, __LINE__, cmd->se_tfo->get_task_tag(cmd));
1735
1736                 cmd->transport_state &= ~CMD_T_ACTIVE;
1737                 spin_unlock_irq(&cmd->t_state_lock);
1738                 complete(&cmd->transport_lun_stop_comp);
1739                 return;
1740         }
1741         /*
1742          * Determine if frontend context caller is requesting the stopping of
1743          * this command for frontend exceptions.
1744          */
1745         if (cmd->transport_state & CMD_T_STOP) {
1746                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1747                         __func__, __LINE__,
1748                         cmd->se_tfo->get_task_tag(cmd));
1749
1750                 spin_unlock_irq(&cmd->t_state_lock);
1751                 complete(&cmd->t_transport_stop_comp);
1752                 return;
1753         }
1754
1755         cmd->t_state = TRANSPORT_PROCESSING;
1756         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1757         spin_unlock_irq(&cmd->t_state_lock);
1758
1759         if (target_handle_task_attr(cmd)) {
1760                 spin_lock_irq(&cmd->t_state_lock);
1761                 cmd->transport_state &= ~CMD_T_BUSY|CMD_T_SENT;
1762                 spin_unlock_irq(&cmd->t_state_lock);
1763                 return;
1764         }
1765
1766         __target_execute_cmd(cmd);
1767 }
1768 EXPORT_SYMBOL(target_execute_cmd);
1769
1770 /*
1771  * Process all commands up to the last received ORDERED task attribute which
1772  * requires another blocking boundary
1773  */
1774 static void target_restart_delayed_cmds(struct se_device *dev)
1775 {
1776         for (;;) {
1777                 struct se_cmd *cmd;
1778
1779                 spin_lock(&dev->delayed_cmd_lock);
1780                 if (list_empty(&dev->delayed_cmd_list)) {
1781                         spin_unlock(&dev->delayed_cmd_lock);
1782                         break;
1783                 }
1784
1785                 cmd = list_entry(dev->delayed_cmd_list.next,
1786                                  struct se_cmd, se_delayed_node);
1787                 list_del(&cmd->se_delayed_node);
1788                 spin_unlock(&dev->delayed_cmd_lock);
1789
1790                 __target_execute_cmd(cmd);
1791
1792                 if (cmd->sam_task_attr == MSG_ORDERED_TAG)
1793                         break;
1794         }
1795 }
1796
1797 /*
1798  * Called from I/O completion to determine which dormant/delayed
1799  * and ordered cmds need to have their tasks added to the execution queue.
1800  */
1801 static void transport_complete_task_attr(struct se_cmd *cmd)
1802 {
1803         struct se_device *dev = cmd->se_dev;
1804
1805         if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
1806                 return;
1807
1808         if (cmd->sam_task_attr == MSG_SIMPLE_TAG) {
1809                 atomic_dec(&dev->simple_cmds);
1810                 smp_mb__after_atomic_dec();
1811                 dev->dev_cur_ordered_id++;
1812                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1813                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1814                         cmd->se_ordered_id);
1815         } else if (cmd->sam_task_attr == MSG_HEAD_TAG) {
1816                 dev->dev_cur_ordered_id++;
1817                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1818                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1819                         cmd->se_ordered_id);
1820         } else if (cmd->sam_task_attr == MSG_ORDERED_TAG) {
1821                 atomic_dec(&dev->dev_ordered_sync);
1822                 smp_mb__after_atomic_dec();
1823
1824                 dev->dev_cur_ordered_id++;
1825                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1826                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1827         }
1828
1829         target_restart_delayed_cmds(dev);
1830 }
1831
1832 static void transport_complete_qf(struct se_cmd *cmd)
1833 {
1834         int ret = 0;
1835
1836         transport_complete_task_attr(cmd);
1837
1838         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1839                 trace_target_cmd_complete(cmd);
1840                 ret = cmd->se_tfo->queue_status(cmd);
1841                 if (ret)
1842                         goto out;
1843         }
1844
1845         switch (cmd->data_direction) {
1846         case DMA_FROM_DEVICE:
1847                 trace_target_cmd_complete(cmd);
1848                 ret = cmd->se_tfo->queue_data_in(cmd);
1849                 break;
1850         case DMA_TO_DEVICE:
1851                 if (cmd->se_cmd_flags & SCF_BIDI) {
1852                         ret = cmd->se_tfo->queue_data_in(cmd);
1853                         if (ret < 0)
1854                                 break;
1855                 }
1856                 /* Fall through for DMA_TO_DEVICE */
1857         case DMA_NONE:
1858                 trace_target_cmd_complete(cmd);
1859                 ret = cmd->se_tfo->queue_status(cmd);
1860                 break;
1861         default:
1862                 break;
1863         }
1864
1865 out:
1866         if (ret < 0) {
1867                 transport_handle_queue_full(cmd, cmd->se_dev);
1868                 return;
1869         }
1870         transport_lun_remove_cmd(cmd);
1871         transport_cmd_check_stop_to_fabric(cmd);
1872 }
1873
1874 static void transport_handle_queue_full(
1875         struct se_cmd *cmd,
1876         struct se_device *dev)
1877 {
1878         spin_lock_irq(&dev->qf_cmd_lock);
1879         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1880         atomic_inc(&dev->dev_qf_count);
1881         smp_mb__after_atomic_inc();
1882         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1883
1884         schedule_work(&cmd->se_dev->qf_work_queue);
1885 }
1886
1887 static void target_complete_ok_work(struct work_struct *work)
1888 {
1889         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
1890         int ret;
1891
1892         /*
1893          * Check if we need to move delayed/dormant tasks from cmds on the
1894          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
1895          * Attribute.
1896          */
1897         transport_complete_task_attr(cmd);
1898
1899         /*
1900          * Check to schedule QUEUE_FULL work, or execute an existing
1901          * cmd->transport_qf_callback()
1902          */
1903         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
1904                 schedule_work(&cmd->se_dev->qf_work_queue);
1905
1906         /*
1907          * Check if we need to send a sense buffer from
1908          * the struct se_cmd in question.
1909          */
1910         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1911                 WARN_ON(!cmd->scsi_status);
1912                 ret = transport_send_check_condition_and_sense(
1913                                         cmd, 0, 1);
1914                 if (ret == -EAGAIN || ret == -ENOMEM)
1915                         goto queue_full;
1916
1917                 transport_lun_remove_cmd(cmd);
1918                 transport_cmd_check_stop_to_fabric(cmd);
1919                 return;
1920         }
1921         /*
1922          * Check for a callback, used by amongst other things
1923          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
1924          */
1925         if (cmd->transport_complete_callback) {
1926                 sense_reason_t rc;
1927
1928                 rc = cmd->transport_complete_callback(cmd);
1929                 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
1930                         return;
1931                 } else if (rc) {
1932                         ret = transport_send_check_condition_and_sense(cmd,
1933                                                 rc, 0);
1934                         if (ret == -EAGAIN || ret == -ENOMEM)
1935                                 goto queue_full;
1936
1937                         transport_lun_remove_cmd(cmd);
1938                         transport_cmd_check_stop_to_fabric(cmd);
1939                         return;
1940                 }
1941         }
1942
1943         switch (cmd->data_direction) {
1944         case DMA_FROM_DEVICE:
1945                 spin_lock(&cmd->se_lun->lun_sep_lock);
1946                 if (cmd->se_lun->lun_sep) {
1947                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1948                                         cmd->data_length;
1949                 }
1950                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1951
1952                 trace_target_cmd_complete(cmd);
1953                 ret = cmd->se_tfo->queue_data_in(cmd);
1954                 if (ret == -EAGAIN || ret == -ENOMEM)
1955                         goto queue_full;
1956                 break;
1957         case DMA_TO_DEVICE:
1958                 spin_lock(&cmd->se_lun->lun_sep_lock);
1959                 if (cmd->se_lun->lun_sep) {
1960                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
1961                                 cmd->data_length;
1962                 }
1963                 spin_unlock(&cmd->se_lun->lun_sep_lock);
1964                 /*
1965                  * Check if we need to send READ payload for BIDI-COMMAND
1966                  */
1967                 if (cmd->se_cmd_flags & SCF_BIDI) {
1968                         spin_lock(&cmd->se_lun->lun_sep_lock);
1969                         if (cmd->se_lun->lun_sep) {
1970                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
1971                                         cmd->data_length;
1972                         }
1973                         spin_unlock(&cmd->se_lun->lun_sep_lock);
1974                         ret = cmd->se_tfo->queue_data_in(cmd);
1975                         if (ret == -EAGAIN || ret == -ENOMEM)
1976                                 goto queue_full;
1977                         break;
1978                 }
1979                 /* Fall through for DMA_TO_DEVICE */
1980         case DMA_NONE:
1981                 trace_target_cmd_complete(cmd);
1982                 ret = cmd->se_tfo->queue_status(cmd);
1983                 if (ret == -EAGAIN || ret == -ENOMEM)
1984                         goto queue_full;
1985                 break;
1986         default:
1987                 break;
1988         }
1989
1990         transport_lun_remove_cmd(cmd);
1991         transport_cmd_check_stop_to_fabric(cmd);
1992         return;
1993
1994 queue_full:
1995         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
1996                 " data_direction: %d\n", cmd, cmd->data_direction);
1997         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1998         transport_handle_queue_full(cmd, cmd->se_dev);
1999 }
2000
2001 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2002 {
2003         struct scatterlist *sg;
2004         int count;
2005
2006         for_each_sg(sgl, sg, nents, count)
2007                 __free_page(sg_page(sg));
2008
2009         kfree(sgl);
2010 }
2011
2012 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2013 {
2014         /*
2015          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2016          * emulation, and free + reset pointers if necessary..
2017          */
2018         if (!cmd->t_data_sg_orig)
2019                 return;
2020
2021         kfree(cmd->t_data_sg);
2022         cmd->t_data_sg = cmd->t_data_sg_orig;
2023         cmd->t_data_sg_orig = NULL;
2024         cmd->t_data_nents = cmd->t_data_nents_orig;
2025         cmd->t_data_nents_orig = 0;
2026 }
2027
2028 static inline void transport_free_pages(struct se_cmd *cmd)
2029 {
2030         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2031                 transport_reset_sgl_orig(cmd);
2032                 return;
2033         }
2034         transport_reset_sgl_orig(cmd);
2035
2036         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2037         cmd->t_data_sg = NULL;
2038         cmd->t_data_nents = 0;
2039
2040         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2041         cmd->t_bidi_data_sg = NULL;
2042         cmd->t_bidi_data_nents = 0;
2043 }
2044
2045 /**
2046  * transport_release_cmd - free a command
2047  * @cmd:       command to free
2048  *
2049  * This routine unconditionally frees a command, and reference counting
2050  * or list removal must be done in the caller.
2051  */
2052 static int transport_release_cmd(struct se_cmd *cmd)
2053 {
2054         BUG_ON(!cmd->se_tfo);
2055
2056         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2057                 core_tmr_release_req(cmd->se_tmr_req);
2058         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2059                 kfree(cmd->t_task_cdb);
2060         /*
2061          * If this cmd has been setup with target_get_sess_cmd(), drop
2062          * the kref and call ->release_cmd() in kref callback.
2063          */
2064         return target_put_sess_cmd(cmd->se_sess, cmd);
2065 }
2066
2067 /**
2068  * transport_put_cmd - release a reference to a command
2069  * @cmd:       command to release
2070  *
2071  * This routine releases our reference to the command and frees it if possible.
2072  */
2073 static int transport_put_cmd(struct se_cmd *cmd)
2074 {
2075         transport_free_pages(cmd);
2076         return transport_release_cmd(cmd);
2077 }
2078
2079 void *transport_kmap_data_sg(struct se_cmd *cmd)
2080 {
2081         struct scatterlist *sg = cmd->t_data_sg;
2082         struct page **pages;
2083         int i;
2084
2085         /*
2086          * We need to take into account a possible offset here for fabrics like
2087          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2088          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2089          */
2090         if (!cmd->t_data_nents)
2091                 return NULL;
2092
2093         BUG_ON(!sg);
2094         if (cmd->t_data_nents == 1)
2095                 return kmap(sg_page(sg)) + sg->offset;
2096
2097         /* >1 page. use vmap */
2098         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2099         if (!pages)
2100                 return NULL;
2101
2102         /* convert sg[] to pages[] */
2103         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2104                 pages[i] = sg_page(sg);
2105         }
2106
2107         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2108         kfree(pages);
2109         if (!cmd->t_data_vmap)
2110                 return NULL;
2111
2112         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2113 }
2114 EXPORT_SYMBOL(transport_kmap_data_sg);
2115
2116 void transport_kunmap_data_sg(struct se_cmd *cmd)
2117 {
2118         if (!cmd->t_data_nents) {
2119                 return;
2120         } else if (cmd->t_data_nents == 1) {
2121                 kunmap(sg_page(cmd->t_data_sg));
2122                 return;
2123         }
2124
2125         vunmap(cmd->t_data_vmap);
2126         cmd->t_data_vmap = NULL;
2127 }
2128 EXPORT_SYMBOL(transport_kunmap_data_sg);
2129
2130 int
2131 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2132                  bool zero_page)
2133 {
2134         struct scatterlist *sg;
2135         struct page *page;
2136         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2137         unsigned int nent;
2138         int i = 0;
2139
2140         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2141         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2142         if (!sg)
2143                 return -ENOMEM;
2144
2145         sg_init_table(sg, nent);
2146
2147         while (length) {
2148                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2149                 page = alloc_page(GFP_KERNEL | zero_flag);
2150                 if (!page)
2151                         goto out;
2152
2153                 sg_set_page(&sg[i], page, page_len, 0);
2154                 length -= page_len;
2155                 i++;
2156         }
2157         *sgl = sg;
2158         *nents = nent;
2159         return 0;
2160
2161 out:
2162         while (i > 0) {
2163                 i--;
2164                 __free_page(sg_page(&sg[i]));
2165         }
2166         kfree(sg);
2167         return -ENOMEM;
2168 }
2169
2170 /*
2171  * Allocate any required resources to execute the command.  For writes we
2172  * might not have the payload yet, so notify the fabric via a call to
2173  * ->write_pending instead. Otherwise place it on the execution queue.
2174  */
2175 sense_reason_t
2176 transport_generic_new_cmd(struct se_cmd *cmd)
2177 {
2178         int ret = 0;
2179
2180         /*
2181          * Determine is the TCM fabric module has already allocated physical
2182          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2183          * beforehand.
2184          */
2185         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2186             cmd->data_length) {
2187                 bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2188
2189                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2190                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2191                         u32 bidi_length;
2192
2193                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2194                                 bidi_length = cmd->t_task_nolb *
2195                                               cmd->se_dev->dev_attrib.block_size;
2196                         else
2197                                 bidi_length = cmd->data_length;
2198
2199                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2200                                                &cmd->t_bidi_data_nents,
2201                                                bidi_length, zero_flag);
2202                         if (ret < 0)
2203                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2204                 }
2205
2206                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2207                                        cmd->data_length, zero_flag);
2208                 if (ret < 0)
2209                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2210         }
2211         /*
2212          * If this command is not a write we can execute it right here,
2213          * for write buffers we need to notify the fabric driver first
2214          * and let it call back once the write buffers are ready.
2215          */
2216         target_add_to_state_list(cmd);
2217         if (cmd->data_direction != DMA_TO_DEVICE) {
2218                 target_execute_cmd(cmd);
2219                 return 0;
2220         }
2221         transport_cmd_check_stop(cmd, false, true);
2222
2223         ret = cmd->se_tfo->write_pending(cmd);
2224         if (ret == -EAGAIN || ret == -ENOMEM)
2225                 goto queue_full;
2226
2227         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2228         WARN_ON(ret);
2229
2230         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2231
2232 queue_full:
2233         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2234         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2235         transport_handle_queue_full(cmd, cmd->se_dev);
2236         return 0;
2237 }
2238 EXPORT_SYMBOL(transport_generic_new_cmd);
2239
2240 static void transport_write_pending_qf(struct se_cmd *cmd)
2241 {
2242         int ret;
2243
2244         ret = cmd->se_tfo->write_pending(cmd);
2245         if (ret == -EAGAIN || ret == -ENOMEM) {
2246                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2247                          cmd);
2248                 transport_handle_queue_full(cmd, cmd->se_dev);
2249         }
2250 }
2251
2252 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2253 {
2254         unsigned long flags;
2255         int ret = 0;
2256
2257         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2258                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2259                          transport_wait_for_tasks(cmd);
2260
2261                 ret = transport_release_cmd(cmd);
2262         } else {
2263                 if (wait_for_tasks)
2264                         transport_wait_for_tasks(cmd);
2265                 /*
2266                  * Handle WRITE failure case where transport_generic_new_cmd()
2267                  * has already added se_cmd to state_list, but fabric has
2268                  * failed command before I/O submission.
2269                  */
2270                 if (cmd->state_active) {
2271                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2272                         target_remove_from_state_list(cmd);
2273                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2274                 }
2275
2276                 if (cmd->se_lun)
2277                         transport_lun_remove_cmd(cmd);
2278
2279                 ret = transport_put_cmd(cmd);
2280         }
2281         return ret;
2282 }
2283 EXPORT_SYMBOL(transport_generic_free_cmd);
2284
2285 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2286  * @se_sess:    session to reference
2287  * @se_cmd:     command descriptor to add
2288  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2289  */
2290 int target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd,
2291                                bool ack_kref)
2292 {
2293         unsigned long flags;
2294         int ret = 0;
2295
2296         kref_init(&se_cmd->cmd_kref);
2297         /*
2298          * Add a second kref if the fabric caller is expecting to handle
2299          * fabric acknowledgement that requires two target_put_sess_cmd()
2300          * invocations before se_cmd descriptor release.
2301          */
2302         if (ack_kref == true) {
2303                 kref_get(&se_cmd->cmd_kref);
2304                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2305         }
2306
2307         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2308         if (se_sess->sess_tearing_down) {
2309                 ret = -ESHUTDOWN;
2310                 goto out;
2311         }
2312         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2313 out:
2314         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2315         return ret;
2316 }
2317 EXPORT_SYMBOL(target_get_sess_cmd);
2318
2319 static void target_release_cmd_kref(struct kref *kref)
2320 {
2321         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2322         struct se_session *se_sess = se_cmd->se_sess;
2323
2324         if (list_empty(&se_cmd->se_cmd_list)) {
2325                 spin_unlock(&se_sess->sess_cmd_lock);
2326                 se_cmd->se_tfo->release_cmd(se_cmd);
2327                 return;
2328         }
2329         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2330                 spin_unlock(&se_sess->sess_cmd_lock);
2331                 complete(&se_cmd->cmd_wait_comp);
2332                 return;
2333         }
2334         list_del(&se_cmd->se_cmd_list);
2335         spin_unlock(&se_sess->sess_cmd_lock);
2336
2337         se_cmd->se_tfo->release_cmd(se_cmd);
2338 }
2339
2340 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2341  * @se_sess:    session to reference
2342  * @se_cmd:     command descriptor to drop
2343  */
2344 int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd)
2345 {
2346         return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2347                         &se_sess->sess_cmd_lock);
2348 }
2349 EXPORT_SYMBOL(target_put_sess_cmd);
2350
2351 /* target_sess_cmd_list_set_waiting - Flag all commands in
2352  *         sess_cmd_list to complete cmd_wait_comp.  Set
2353  *         sess_tearing_down so no more commands are queued.
2354  * @se_sess:    session to flag
2355  */
2356 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2357 {
2358         struct se_cmd *se_cmd;
2359         unsigned long flags;
2360
2361         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2362         if (se_sess->sess_tearing_down) {
2363                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2364                 return;
2365         }
2366         se_sess->sess_tearing_down = 1;
2367         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2368
2369         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2370                 se_cmd->cmd_wait_set = 1;
2371
2372         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2373 }
2374 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2375
2376 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2377  * @se_sess:    session to wait for active I/O
2378  */
2379 void target_wait_for_sess_cmds(struct se_session *se_sess)
2380 {
2381         struct se_cmd *se_cmd, *tmp_cmd;
2382         unsigned long flags;
2383
2384         list_for_each_entry_safe(se_cmd, tmp_cmd,
2385                                 &se_sess->sess_wait_list, se_cmd_list) {
2386                 list_del(&se_cmd->se_cmd_list);
2387
2388                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2389                         " %d\n", se_cmd, se_cmd->t_state,
2390                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2391
2392                 wait_for_completion(&se_cmd->cmd_wait_comp);
2393                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2394                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2395                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2396
2397                 se_cmd->se_tfo->release_cmd(se_cmd);
2398         }
2399
2400         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2401         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2402         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2403
2404 }
2405 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2406
2407 /*      transport_lun_wait_for_tasks():
2408  *
2409  *      Called from ConfigFS context to stop the passed struct se_cmd to allow
2410  *      an struct se_lun to be successfully shutdown.
2411  */
2412 static int transport_lun_wait_for_tasks(struct se_cmd *cmd, struct se_lun *lun)
2413 {
2414         unsigned long flags;
2415         int ret = 0;
2416
2417         /*
2418          * If the frontend has already requested this struct se_cmd to
2419          * be stopped, we can safely ignore this struct se_cmd.
2420          */
2421         spin_lock_irqsave(&cmd->t_state_lock, flags);
2422         if (cmd->transport_state & CMD_T_STOP) {
2423                 cmd->transport_state &= ~CMD_T_LUN_STOP;
2424
2425                 pr_debug("ConfigFS ITT[0x%08x] - CMD_T_STOP, skipping\n",
2426                          cmd->se_tfo->get_task_tag(cmd));
2427                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2428                 transport_cmd_check_stop(cmd, false, false);
2429                 return -EPERM;
2430         }
2431         cmd->transport_state |= CMD_T_LUN_FE_STOP;
2432         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2433
2434         // XXX: audit task_flags checks.
2435         spin_lock_irqsave(&cmd->t_state_lock, flags);
2436         if ((cmd->transport_state & CMD_T_BUSY) &&
2437             (cmd->transport_state & CMD_T_SENT)) {
2438                 if (!target_stop_cmd(cmd, &flags))
2439                         ret++;
2440         }
2441         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2442
2443         pr_debug("ConfigFS: cmd: %p stop tasks ret:"
2444                         " %d\n", cmd, ret);
2445         if (!ret) {
2446                 pr_debug("ConfigFS: ITT[0x%08x] - stopping cmd....\n",
2447                                 cmd->se_tfo->get_task_tag(cmd));
2448                 wait_for_completion(&cmd->transport_lun_stop_comp);
2449                 pr_debug("ConfigFS: ITT[0x%08x] - stopped cmd....\n",
2450                                 cmd->se_tfo->get_task_tag(cmd));
2451         }
2452
2453         return 0;
2454 }
2455
2456 static void __transport_clear_lun_from_sessions(struct se_lun *lun)
2457 {
2458         struct se_cmd *cmd = NULL;
2459         unsigned long lun_flags, cmd_flags;
2460         /*
2461          * Do exception processing and return CHECK_CONDITION status to the
2462          * Initiator Port.
2463          */
2464         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2465         while (!list_empty(&lun->lun_cmd_list)) {
2466                 cmd = list_first_entry(&lun->lun_cmd_list,
2467                        struct se_cmd, se_lun_node);
2468                 list_del_init(&cmd->se_lun_node);
2469
2470                 spin_lock(&cmd->t_state_lock);
2471                 pr_debug("SE_LUN[%d] - Setting cmd->transport"
2472                         "_lun_stop for  ITT: 0x%08x\n",
2473                         cmd->se_lun->unpacked_lun,
2474                         cmd->se_tfo->get_task_tag(cmd));
2475                 cmd->transport_state |= CMD_T_LUN_STOP;
2476                 spin_unlock(&cmd->t_state_lock);
2477
2478                 spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2479
2480                 if (!cmd->se_lun) {
2481                         pr_err("ITT: 0x%08x, [i,t]_state: %u/%u\n",
2482                                 cmd->se_tfo->get_task_tag(cmd),
2483                                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2484                         BUG();
2485                 }
2486                 /*
2487                  * If the Storage engine still owns the iscsi_cmd_t, determine
2488                  * and/or stop its context.
2489                  */
2490                 pr_debug("SE_LUN[%d] - ITT: 0x%08x before transport"
2491                         "_lun_wait_for_tasks()\n", cmd->se_lun->unpacked_lun,
2492                         cmd->se_tfo->get_task_tag(cmd));
2493
2494                 if (transport_lun_wait_for_tasks(cmd, cmd->se_lun) < 0) {
2495                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2496                         continue;
2497                 }
2498
2499                 pr_debug("SE_LUN[%d] - ITT: 0x%08x after transport_lun"
2500                         "_wait_for_tasks(): SUCCESS\n",
2501                         cmd->se_lun->unpacked_lun,
2502                         cmd->se_tfo->get_task_tag(cmd));
2503
2504                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2505                 if (!(cmd->transport_state & CMD_T_DEV_ACTIVE)) {
2506                         spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2507                         goto check_cond;
2508                 }
2509                 cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
2510                 target_remove_from_state_list(cmd);
2511                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2512
2513                 /*
2514                  * The Storage engine stopped this struct se_cmd before it was
2515                  * send to the fabric frontend for delivery back to the
2516                  * Initiator Node.  Return this SCSI CDB back with an
2517                  * CHECK_CONDITION status.
2518                  */
2519 check_cond:
2520                 transport_send_check_condition_and_sense(cmd,
2521                                 TCM_NON_EXISTENT_LUN, 0);
2522                 /*
2523                  *  If the fabric frontend is waiting for this iscsi_cmd_t to
2524                  * be released, notify the waiting thread now that LU has
2525                  * finished accessing it.
2526                  */
2527                 spin_lock_irqsave(&cmd->t_state_lock, cmd_flags);
2528                 if (cmd->transport_state & CMD_T_LUN_FE_STOP) {
2529                         pr_debug("SE_LUN[%d] - Detected FE stop for"
2530                                 " struct se_cmd: %p ITT: 0x%08x\n",
2531                                 lun->unpacked_lun,
2532                                 cmd, cmd->se_tfo->get_task_tag(cmd));
2533
2534                         spin_unlock_irqrestore(&cmd->t_state_lock,
2535                                         cmd_flags);
2536                         transport_cmd_check_stop(cmd, false, false);
2537                         complete(&cmd->transport_lun_fe_stop_comp);
2538                         spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2539                         continue;
2540                 }
2541                 pr_debug("SE_LUN[%d] - ITT: 0x%08x finished processing\n",
2542                         lun->unpacked_lun, cmd->se_tfo->get_task_tag(cmd));
2543
2544                 spin_unlock_irqrestore(&cmd->t_state_lock, cmd_flags);
2545                 spin_lock_irqsave(&lun->lun_cmd_lock, lun_flags);
2546         }
2547         spin_unlock_irqrestore(&lun->lun_cmd_lock, lun_flags);
2548 }
2549
2550 static int transport_clear_lun_thread(void *p)
2551 {
2552         struct se_lun *lun = p;
2553
2554         __transport_clear_lun_from_sessions(lun);
2555         complete(&lun->lun_shutdown_comp);
2556
2557         return 0;
2558 }
2559
2560 int transport_clear_lun_from_sessions(struct se_lun *lun)
2561 {
2562         struct task_struct *kt;
2563
2564         kt = kthread_run(transport_clear_lun_thread, lun,
2565                         "tcm_cl_%u", lun->unpacked_lun);
2566         if (IS_ERR(kt)) {
2567                 pr_err("Unable to start clear_lun thread\n");
2568                 return PTR_ERR(kt);
2569         }
2570         wait_for_completion(&lun->lun_shutdown_comp);
2571
2572         return 0;
2573 }
2574
2575 /**
2576  * transport_wait_for_tasks - wait for completion to occur
2577  * @cmd:        command to wait
2578  *
2579  * Called from frontend fabric context to wait for storage engine
2580  * to pause and/or release frontend generated struct se_cmd.
2581  */
2582 bool transport_wait_for_tasks(struct se_cmd *cmd)
2583 {
2584         unsigned long flags;
2585
2586         spin_lock_irqsave(&cmd->t_state_lock, flags);
2587         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2588             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2589                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2590                 return false;
2591         }
2592
2593         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2594             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2595                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2596                 return false;
2597         }
2598         /*
2599          * If we are already stopped due to an external event (ie: LUN shutdown)
2600          * sleep until the connection can have the passed struct se_cmd back.
2601          * The cmd->transport_lun_stopped_sem will be upped by
2602          * transport_clear_lun_from_sessions() once the ConfigFS context caller
2603          * has completed its operation on the struct se_cmd.
2604          */
2605         if (cmd->transport_state & CMD_T_LUN_STOP) {
2606                 pr_debug("wait_for_tasks: Stopping"
2607                         " wait_for_completion(&cmd->t_tasktransport_lun_fe"
2608                         "_stop_comp); for ITT: 0x%08x\n",
2609                         cmd->se_tfo->get_task_tag(cmd));
2610                 /*
2611                  * There is a special case for WRITES where a FE exception +
2612                  * LUN shutdown means ConfigFS context is still sleeping on
2613                  * transport_lun_stop_comp in transport_lun_wait_for_tasks().
2614                  * We go ahead and up transport_lun_stop_comp just to be sure
2615                  * here.
2616                  */
2617                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2618                 complete(&cmd->transport_lun_stop_comp);
2619                 wait_for_completion(&cmd->transport_lun_fe_stop_comp);
2620                 spin_lock_irqsave(&cmd->t_state_lock, flags);
2621
2622                 target_remove_from_state_list(cmd);
2623                 /*
2624                  * At this point, the frontend who was the originator of this
2625                  * struct se_cmd, now owns the structure and can be released through
2626                  * normal means below.
2627                  */
2628                 pr_debug("wait_for_tasks: Stopped"
2629                         " wait_for_completion(&cmd->t_tasktransport_lun_fe_"
2630                         "stop_comp); for ITT: 0x%08x\n",
2631                         cmd->se_tfo->get_task_tag(cmd));
2632
2633                 cmd->transport_state &= ~CMD_T_LUN_STOP;
2634         }
2635
2636         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2637                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2638                 return false;
2639         }
2640
2641         cmd->transport_state |= CMD_T_STOP;
2642
2643         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2644                 " i_state: %d, t_state: %d, CMD_T_STOP\n",
2645                 cmd, cmd->se_tfo->get_task_tag(cmd),
2646                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2647
2648         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2649
2650         wait_for_completion(&cmd->t_transport_stop_comp);
2651
2652         spin_lock_irqsave(&cmd->t_state_lock, flags);
2653         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2654
2655         pr_debug("wait_for_tasks: Stopped wait_for_completion("
2656                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2657                 cmd->se_tfo->get_task_tag(cmd));
2658
2659         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2660
2661         return true;
2662 }
2663 EXPORT_SYMBOL(transport_wait_for_tasks);
2664
2665 static int transport_get_sense_codes(
2666         struct se_cmd *cmd,
2667         u8 *asc,
2668         u8 *ascq)
2669 {
2670         *asc = cmd->scsi_asc;
2671         *ascq = cmd->scsi_ascq;
2672
2673         return 0;
2674 }
2675
2676 int
2677 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2678                 sense_reason_t reason, int from_transport)
2679 {
2680         unsigned char *buffer = cmd->sense_buffer;
2681         unsigned long flags;
2682         u8 asc = 0, ascq = 0;
2683
2684         spin_lock_irqsave(&cmd->t_state_lock, flags);
2685         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2686                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2687                 return 0;
2688         }
2689         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2690         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2691
2692         if (!reason && from_transport)
2693                 goto after_reason;
2694
2695         if (!from_transport)
2696                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2697
2698         /*
2699          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2700          * SENSE KEY values from include/scsi/scsi.h
2701          */
2702         switch (reason) {
2703         case TCM_NO_SENSE:
2704                 /* CURRENT ERROR */
2705                 buffer[0] = 0x70;
2706                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2707                 /* Not Ready */
2708                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2709                 /* NO ADDITIONAL SENSE INFORMATION */
2710                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2711                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2712                 break;
2713         case TCM_NON_EXISTENT_LUN:
2714                 /* CURRENT ERROR */
2715                 buffer[0] = 0x70;
2716                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2717                 /* ILLEGAL REQUEST */
2718                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2719                 /* LOGICAL UNIT NOT SUPPORTED */
2720                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2721                 break;
2722         case TCM_UNSUPPORTED_SCSI_OPCODE:
2723         case TCM_SECTOR_COUNT_TOO_MANY:
2724                 /* CURRENT ERROR */
2725                 buffer[0] = 0x70;
2726                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2727                 /* ILLEGAL REQUEST */
2728                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2729                 /* INVALID COMMAND OPERATION CODE */
2730                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2731                 break;
2732         case TCM_UNKNOWN_MODE_PAGE:
2733                 /* CURRENT ERROR */
2734                 buffer[0] = 0x70;
2735                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2736                 /* ILLEGAL REQUEST */
2737                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2738                 /* INVALID FIELD IN CDB */
2739                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2740                 break;
2741         case TCM_CHECK_CONDITION_ABORT_CMD:
2742                 /* CURRENT ERROR */
2743                 buffer[0] = 0x70;
2744                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2745                 /* ABORTED COMMAND */
2746                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2747                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2748                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2749                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2750                 break;
2751         case TCM_INCORRECT_AMOUNT_OF_DATA:
2752                 /* CURRENT ERROR */
2753                 buffer[0] = 0x70;
2754                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2755                 /* ABORTED COMMAND */
2756                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2757                 /* WRITE ERROR */
2758                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2759                 /* NOT ENOUGH UNSOLICITED DATA */
2760                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2761                 break;
2762         case TCM_INVALID_CDB_FIELD:
2763                 /* CURRENT ERROR */
2764                 buffer[0] = 0x70;
2765                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2766                 /* ILLEGAL REQUEST */
2767                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2768                 /* INVALID FIELD IN CDB */
2769                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2770                 break;
2771         case TCM_INVALID_PARAMETER_LIST:
2772                 /* CURRENT ERROR */
2773                 buffer[0] = 0x70;
2774                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2775                 /* ILLEGAL REQUEST */
2776                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2777                 /* INVALID FIELD IN PARAMETER LIST */
2778                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2779                 break;
2780         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2781                 /* CURRENT ERROR */
2782                 buffer[0] = 0x70;
2783                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2784                 /* ILLEGAL REQUEST */
2785                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2786                 /* PARAMETER LIST LENGTH ERROR */
2787                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2788                 break;
2789         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2790                 /* CURRENT ERROR */
2791                 buffer[0] = 0x70;
2792                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2793                 /* ABORTED COMMAND */
2794                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2795                 /* WRITE ERROR */
2796                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2797                 /* UNEXPECTED_UNSOLICITED_DATA */
2798                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2799                 break;
2800         case TCM_SERVICE_CRC_ERROR:
2801                 /* CURRENT ERROR */
2802                 buffer[0] = 0x70;
2803                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2804                 /* ABORTED COMMAND */
2805                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2806                 /* PROTOCOL SERVICE CRC ERROR */
2807                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2808                 /* N/A */
2809                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2810                 break;
2811         case TCM_SNACK_REJECTED:
2812                 /* CURRENT ERROR */
2813                 buffer[0] = 0x70;
2814                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2815                 /* ABORTED COMMAND */
2816                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2817                 /* READ ERROR */
2818                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2819                 /* FAILED RETRANSMISSION REQUEST */
2820                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2821                 break;
2822         case TCM_WRITE_PROTECTED:
2823                 /* CURRENT ERROR */
2824                 buffer[0] = 0x70;
2825                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2826                 /* DATA PROTECT */
2827                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2828                 /* WRITE PROTECTED */
2829                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2830                 break;
2831         case TCM_ADDRESS_OUT_OF_RANGE:
2832                 /* CURRENT ERROR */
2833                 buffer[0] = 0x70;
2834                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2835                 /* ILLEGAL REQUEST */
2836                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2837                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2838                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2839                 break;
2840         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2841                 /* CURRENT ERROR */
2842                 buffer[0] = 0x70;
2843                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2844                 /* UNIT ATTENTION */
2845                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2846                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2847                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2848                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2849                 break;
2850         case TCM_CHECK_CONDITION_NOT_READY:
2851                 /* CURRENT ERROR */
2852                 buffer[0] = 0x70;
2853                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2854                 /* Not Ready */
2855                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2856                 transport_get_sense_codes(cmd, &asc, &ascq);
2857                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2858                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2859                 break;
2860         case TCM_MISCOMPARE_VERIFY:
2861                 /* CURRENT ERROR */
2862                 buffer[0] = 0x70;
2863                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2864                 buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
2865                 /* MISCOMPARE DURING VERIFY OPERATION */
2866                 buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
2867                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
2868                 break;
2869         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2870         default:
2871                 /* CURRENT ERROR */
2872                 buffer[0] = 0x70;
2873                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2874                 /*
2875                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2876                  * Solaris initiators.  Returning NOT READY instead means the
2877                  * operations will be retried a finite number of times and we
2878                  * can survive intermittent errors.
2879                  */
2880                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2881                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2882                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2883                 break;
2884         }
2885         /*
2886          * This code uses linux/include/scsi/scsi.h SAM status codes!
2887          */
2888         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2889         /*
2890          * Automatically padded, this value is encoded in the fabric's
2891          * data_length response PDU containing the SCSI defined sense data.
2892          */
2893         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2894
2895 after_reason:
2896         trace_target_cmd_complete(cmd);
2897         return cmd->se_tfo->queue_status(cmd);
2898 }
2899 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2900
2901 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2902 {
2903         if (!(cmd->transport_state & CMD_T_ABORTED))
2904                 return 0;
2905
2906         if (!send_status || (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
2907                 return 1;
2908
2909         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2910                  cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2911
2912         cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
2913         trace_target_cmd_complete(cmd);
2914         cmd->se_tfo->queue_status(cmd);
2915
2916         return 1;
2917 }
2918 EXPORT_SYMBOL(transport_check_aborted_status);
2919
2920 void transport_send_task_abort(struct se_cmd *cmd)
2921 {
2922         unsigned long flags;
2923
2924         spin_lock_irqsave(&cmd->t_state_lock, flags);
2925         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION | SCF_SENT_DELAYED_TAS)) {
2926                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2927                 return;
2928         }
2929         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2930
2931         /*
2932          * If there are still expected incoming fabric WRITEs, we wait
2933          * until until they have completed before sending a TASK_ABORTED
2934          * response.  This response with TASK_ABORTED status will be
2935          * queued back to fabric module by transport_check_aborted_status().
2936          */
2937         if (cmd->data_direction == DMA_TO_DEVICE) {
2938                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2939                         cmd->transport_state |= CMD_T_ABORTED;
2940                         smp_mb__after_atomic_inc();
2941                 }
2942         }
2943         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2944
2945         transport_lun_remove_cmd(cmd);
2946
2947         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
2948                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
2949                 cmd->se_tfo->get_task_tag(cmd));
2950
2951         trace_target_cmd_complete(cmd);
2952         cmd->se_tfo->queue_status(cmd);
2953 }
2954
2955 static void target_tmr_work(struct work_struct *work)
2956 {
2957         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2958         struct se_device *dev = cmd->se_dev;
2959         struct se_tmr_req *tmr = cmd->se_tmr_req;
2960         int ret;
2961
2962         switch (tmr->function) {
2963         case TMR_ABORT_TASK:
2964                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2965                 break;
2966         case TMR_ABORT_TASK_SET:
2967         case TMR_CLEAR_ACA:
2968         case TMR_CLEAR_TASK_SET:
2969                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2970                 break;
2971         case TMR_LUN_RESET:
2972                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2973                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2974                                          TMR_FUNCTION_REJECTED;
2975                 break;
2976         case TMR_TARGET_WARM_RESET:
2977                 tmr->response = TMR_FUNCTION_REJECTED;
2978                 break;
2979         case TMR_TARGET_COLD_RESET:
2980                 tmr->response = TMR_FUNCTION_REJECTED;
2981                 break;
2982         default:
2983                 pr_err("Uknown TMR function: 0x%02x.\n",
2984                                 tmr->function);
2985                 tmr->response = TMR_FUNCTION_REJECTED;
2986                 break;
2987         }
2988
2989         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
2990         cmd->se_tfo->queue_tm_rsp(cmd);
2991
2992         transport_cmd_check_stop_to_fabric(cmd);
2993 }
2994
2995 int transport_generic_handle_tmr(
2996         struct se_cmd *cmd)
2997 {
2998         INIT_WORK(&cmd->work, target_tmr_work);
2999         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3000         return 0;
3001 }
3002 EXPORT_SYMBOL(transport_generic_handle_tmr);