drivers/target/target_core_transport.c

   1 /*******************************************************************************
   2  * Filename:  target_core_transport.c
   3  *
   4  * This file contains the Generic Target Engine Core.
   5  *
   6  * (c) Copyright 2002-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/net.h>
  27 #include <linux/delay.h>
  28 #include <linux/string.h>
  29 #include <linux/timer.h>
  30 #include <linux/slab.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/kthread.h>
  33 #include <linux/in.h>
  34 #include <linux/cdrom.h>
  35 #include <linux/module.h>
  36 #include <linux/ratelimit.h>
  37 #include <linux/vmalloc.h>
  38 #include <asm/unaligned.h>
  39 #include <net/sock.h>
  40 #include <net/tcp.h>
  41 #include <scsi/scsi_proto.h>
  42 #include <scsi/scsi_common.h>
  43
  44 #include <target/target_core_base.h>
  45 #include <target/target_core_backend.h>
  46 #include <target/target_core_fabric.h>
  47
  48 #include "target_core_internal.h"
  49 #include "target_core_alua.h"
  50 #include "target_core_pr.h"
  51 #include "target_core_ua.h"
  52
  53 #define CREATE_TRACE_POINTS
  54 #include <trace/events/target.h>
  55
  56 static struct workqueue_struct *target_completion_wq;
  57 static struct kmem_cache *se_sess_cache;
  58 struct kmem_cache *se_ua_cache;
  59 struct kmem_cache *t10_pr_reg_cache;
  60 struct kmem_cache *t10_alua_lu_gp_cache;
  61 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  62 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  63 struct kmem_cache *t10_alua_lba_map_cache;
  64 struct kmem_cache *t10_alua_lba_map_mem_cache;
  65
  66 static void transport_complete_task_attr(struct se_cmd *cmd);
  67 static void transport_handle_queue_full(struct se_cmd *cmd,
  68                 struct se_device *dev);
  69 static int transport_put_cmd(struct se_cmd *cmd);
  70 static void target_complete_ok_work(struct work_struct *work);
  71
  72 int init_se_kmem_caches(void)
  73 {
  74         se_sess_cache = kmem_cache_create("se_sess_cache",
  75                         sizeof(struct se_session), __alignof__(struct se_session),
  76                         0, NULL);
  77         if (!se_sess_cache) {
  78                 pr_err("kmem_cache_create() for struct se_session"
  79                                 " failed\n");
  80                 goto out;
  81         }
  82         se_ua_cache = kmem_cache_create("se_ua_cache",
  83                         sizeof(struct se_ua), __alignof__(struct se_ua),
  84                         0, NULL);
  85         if (!se_ua_cache) {
  86                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  87                 goto out_free_sess_cache;
  88         }
  89         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  90                         sizeof(struct t10_pr_registration),
  91                         __alignof__(struct t10_pr_registration), 0, NULL);
  92         if (!t10_pr_reg_cache) {
  93                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  94                                 " failed\n");
  95                 goto out_free_ua_cache;
  96         }
  97         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
  98                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
  99                         0, NULL);
 100         if (!t10_alua_lu_gp_cache) {
 101                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 102                                 " failed\n");
 103                 goto out_free_pr_reg_cache;
 104         }
 105         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 106                         sizeof(struct t10_alua_lu_gp_member),
 107                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 108         if (!t10_alua_lu_gp_mem_cache) {
 109                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 110                                 "cache failed\n");
 111                 goto out_free_lu_gp_cache;
 112         }
 113         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 114                         sizeof(struct t10_alua_tg_pt_gp),
 115                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 116         if (!t10_alua_tg_pt_gp_cache) {
 117                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 118                                 "cache failed\n");
 119                 goto out_free_lu_gp_mem_cache;
 120         }
 121         t10_alua_lba_map_cache = kmem_cache_create(
 122                         "t10_alua_lba_map_cache",
 123                         sizeof(struct t10_alua_lba_map),
 124                         __alignof__(struct t10_alua_lba_map), 0, NULL);
 125         if (!t10_alua_lba_map_cache) {
 126                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
 127                                 "cache failed\n");
 128                 goto out_free_tg_pt_gp_cache;
 129         }
 130         t10_alua_lba_map_mem_cache = kmem_cache_create(
 131                         "t10_alua_lba_map_mem_cache",
 132                         sizeof(struct t10_alua_lba_map_member),
 133                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
 134         if (!t10_alua_lba_map_mem_cache) {
 135                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
 136                                 "cache failed\n");
 137                 goto out_free_lba_map_cache;
 138         }
 139
 140         target_completion_wq = alloc_workqueue("target_completion",
 141                                                WQ_MEM_RECLAIM, 0);
 142         if (!target_completion_wq)
 143                 goto out_free_lba_map_mem_cache;
 144
 145         return 0;
 146
 147 out_free_lba_map_mem_cache:
 148         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 149 out_free_lba_map_cache:
 150         kmem_cache_destroy(t10_alua_lba_map_cache);
 151 out_free_tg_pt_gp_cache:
 152         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 153 out_free_lu_gp_mem_cache:
 154         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 155 out_free_lu_gp_cache:
 156         kmem_cache_destroy(t10_alua_lu_gp_cache);
 157 out_free_pr_reg_cache:
 158         kmem_cache_destroy(t10_pr_reg_cache);
 159 out_free_ua_cache:
 160         kmem_cache_destroy(se_ua_cache);
 161 out_free_sess_cache:
 162         kmem_cache_destroy(se_sess_cache);
 163 out:
 164         return -ENOMEM;
 165 }
 166
 167 void release_se_kmem_caches(void)
 168 {
 169         destroy_workqueue(target_completion_wq);
 170         kmem_cache_destroy(se_sess_cache);
 171         kmem_cache_destroy(se_ua_cache);
 172         kmem_cache_destroy(t10_pr_reg_cache);
 173         kmem_cache_destroy(t10_alua_lu_gp_cache);
 174         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 175         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 176         kmem_cache_destroy(t10_alua_lba_map_cache);
 177         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 178 }
 179
 180 /* This code ensures unique mib indexes are handed out. */
 181 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 182 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 183
 184 /*
 185  * Allocate a new row index for the entry type specified
 186  */
 187 u32 scsi_get_new_index(scsi_index_t type)
 188 {
 189         u32 new_index;
 190
 191         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 192
 193         spin_lock(&scsi_mib_index_lock);
 194         new_index = ++scsi_mib_index[type];
 195         spin_unlock(&scsi_mib_index_lock);
 196
 197         return new_index;
 198 }
 199
 200 void transport_subsystem_check_init(void)
 201 {
 202         int ret;
 203         static int sub_api_initialized;
 204
 205         if (sub_api_initialized)
 206                 return;
 207
 208         ret = request_module("target_core_iblock");
 209         if (ret != 0)
 210                 pr_err("Unable to load target_core_iblock\n");
 211
 212         ret = request_module("target_core_file");
 213         if (ret != 0)
 214                 pr_err("Unable to load target_core_file\n");
 215
 216         ret = request_module("target_core_pscsi");
 217         if (ret != 0)
 218                 pr_err("Unable to load target_core_pscsi\n");
 219
 220         ret = request_module("target_core_user");
 221         if (ret != 0)
 222                 pr_err("Unable to load target_core_user\n");
 223
 224         sub_api_initialized = 1;
 225 }
 226
 227 struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
 228 {
 229         struct se_session *se_sess;
 230
 231         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 232         if (!se_sess) {
 233                 pr_err("Unable to allocate struct se_session from"
 234                                 " se_sess_cache\n");
 235                 return ERR_PTR(-ENOMEM);
 236         }
 237         INIT_LIST_HEAD(&se_sess->sess_list);
 238         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 239         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 240         INIT_LIST_HEAD(&se_sess->sess_wait_list);
 241         spin_lock_init(&se_sess->sess_cmd_lock);
 242         kref_init(&se_sess->sess_kref);
 243         se_sess->sup_prot_ops = sup_prot_ops;
 244
 245         return se_sess;
 246 }
 247 EXPORT_SYMBOL(transport_init_session);
 248
 249 int transport_alloc_session_tags(struct se_session *se_sess,
 250                                  unsigned int tag_num, unsigned int tag_size)
 251 {
 252         int rc;
 253
 254         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
 255                                         GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
 256         if (!se_sess->sess_cmd_map) {
 257                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
 258                 if (!se_sess->sess_cmd_map) {
 259                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 260                         return -ENOMEM;
 261                 }
 262         }
 263
 264         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
 265         if (rc < 0) {
 266                 pr_err("Unable to init se_sess->sess_tag_pool,"
 267                         " tag_num: %u\n", tag_num);
 268                 kvfree(se_sess->sess_cmd_map);
 269                 se_sess->sess_cmd_map = NULL;
 270                 return -ENOMEM;
 271         }
 272
 273         return 0;
 274 }
 275 EXPORT_SYMBOL(transport_alloc_session_tags);
 276
 277 struct se_session *transport_init_session_tags(unsigned int tag_num,
 278                                                unsigned int tag_size,
 279                                                enum target_prot_op sup_prot_ops)
 280 {
 281         struct se_session *se_sess;
 282         int rc;
 283
 284         se_sess = transport_init_session(sup_prot_ops);
 285         if (IS_ERR(se_sess))
 286                 return se_sess;
 287
 288         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 289         if (rc < 0) {
 290                 transport_free_session(se_sess);
 291                 return ERR_PTR(-ENOMEM);
 292         }
 293
 294         return se_sess;
 295 }
 296 EXPORT_SYMBOL(transport_init_session_tags);
 297
 298 /*
 299  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 300  */
 301 void __transport_register_session(
 302         struct se_portal_group *se_tpg,
 303         struct se_node_acl *se_nacl,
 304         struct se_session *se_sess,
 305         void *fabric_sess_ptr)
 306 {
 307         const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
 308         unsigned char buf[PR_REG_ISID_LEN];
 309
 310         se_sess->se_tpg = se_tpg;
 311         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 312         /*
 313          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 314          *
 315          * Only set for struct se_session's that will actually be moving I/O.
 316          * eg: *NOT* discovery sessions.
 317          */
 318         if (se_nacl) {
 319                 /*
 320                  *
 321                  * Determine if fabric allows for T10-PI feature bits exposed to
 322                  * initiators for device backends with !dev->dev_attrib.pi_prot_type.
 323                  *
 324                  * If so, then always save prot_type on a per se_node_acl node
 325                  * basis and re-instate the previous sess_prot_type to avoid
 326                  * disabling PI from below any previously initiator side
 327                  * registered LUNs.
 328                  */
 329                 if (se_nacl->saved_prot_type)
 330                         se_sess->sess_prot_type = se_nacl->saved_prot_type;
 331                 else if (tfo->tpg_check_prot_fabric_only)
 332                         se_sess->sess_prot_type = se_nacl->saved_prot_type =
 333                                         tfo->tpg_check_prot_fabric_only(se_tpg);
 334                 /*
 335                  * If the fabric module supports an ISID based TransportID,
 336                  * save this value in binary from the fabric I_T Nexus now.
 337                  */
 338                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 339                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 340                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 341                                         &buf[0], PR_REG_ISID_LEN);
 342                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 343                 }
 344
 345                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 346                 /*
 347                  * The se_nacl->nacl_sess pointer will be set to the
 348                  * last active I_T Nexus for each struct se_node_acl.
 349                  */
 350                 se_nacl->nacl_sess = se_sess;
 351
 352                 list_add_tail(&se_sess->sess_acl_list,
 353                               &se_nacl->acl_sess_list);
 354                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 355         }
 356         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 357
 358         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 359                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 360 }
 361 EXPORT_SYMBOL(__transport_register_session);
 362
 363 void transport_register_session(
 364         struct se_portal_group *se_tpg,
 365         struct se_node_acl *se_nacl,
 366         struct se_session *se_sess,
 367         void *fabric_sess_ptr)
 368 {
 369         unsigned long flags;
 370
 371         spin_lock_irqsave(&se_tpg->session_lock, flags);
 372         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 373         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 374 }
 375 EXPORT_SYMBOL(transport_register_session);
 376
 377 static void target_release_session(struct kref *kref)
 378 {
 379         struct se_session *se_sess = container_of(kref,
 380                         struct se_session, sess_kref);
 381         struct se_portal_group *se_tpg = se_sess->se_tpg;
 382
 383         se_tpg->se_tpg_tfo->close_session(se_sess);
 384 }
 385
 386 void target_get_session(struct se_session *se_sess)
 387 {
 388         kref_get(&se_sess->sess_kref);
 389 }
 390 EXPORT_SYMBOL(target_get_session);
 391
 392 void target_put_session(struct se_session *se_sess)
 393 {
 394         kref_put(&se_sess->sess_kref, target_release_session);
 395 }
 396 EXPORT_SYMBOL(target_put_session);
 397
 398 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
 399 {
 400         struct se_session *se_sess;
 401         ssize_t len = 0;
 402
 403         spin_lock_bh(&se_tpg->session_lock);
 404         list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
 405                 if (!se_sess->se_node_acl)
 406                         continue;
 407                 if (!se_sess->se_node_acl->dynamic_node_acl)
 408                         continue;
 409                 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
 410                         break;
 411
 412                 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
 413                                 se_sess->se_node_acl->initiatorname);
 414                 len += 1; /* Include NULL terminator */
 415         }
 416         spin_unlock_bh(&se_tpg->session_lock);
 417
 418         return len;
 419 }
 420 EXPORT_SYMBOL(target_show_dynamic_sessions);
 421
 422 static void target_complete_nacl(struct kref *kref)
 423 {
 424         struct se_node_acl *nacl = container_of(kref,
 425                                 struct se_node_acl, acl_kref);
 426
 427         complete(&nacl->acl_free_comp);
 428 }
 429
 430 void target_put_nacl(struct se_node_acl *nacl)
 431 {
 432         kref_put(&nacl->acl_kref, target_complete_nacl);
 433 }
 434 EXPORT_SYMBOL(target_put_nacl);
 435
 436 void transport_deregister_session_configfs(struct se_session *se_sess)
 437 {
 438         struct se_node_acl *se_nacl;
 439         unsigned long flags;
 440         /*
 441          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 442          */
 443         se_nacl = se_sess->se_node_acl;
 444         if (se_nacl) {
 445                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 446                 if (se_nacl->acl_stop == 0)
 447                         list_del(&se_sess->sess_acl_list);
 448                 /*
 449                  * If the session list is empty, then clear the pointer.
 450                  * Otherwise, set the struct se_session pointer from the tail
 451                  * element of the per struct se_node_acl active session list.
 452                  */
 453                 if (list_empty(&se_nacl->acl_sess_list))
 454                         se_nacl->nacl_sess = NULL;
 455                 else {
 456                         se_nacl->nacl_sess = container_of(
 457                                         se_nacl->acl_sess_list.prev,
 458                                         struct se_session, sess_acl_list);
 459                 }
 460                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 461         }
 462 }
 463 EXPORT_SYMBOL(transport_deregister_session_configfs);
 464
 465 void transport_free_session(struct se_session *se_sess)
 466 {
 467         struct se_node_acl *se_nacl = se_sess->se_node_acl;
 468         /*
 469          * Drop the se_node_acl->nacl_kref obtained from within
 470          * core_tpg_get_initiator_node_acl().
 471          */
 472         if (se_nacl) {
 473                 se_sess->se_node_acl = NULL;
 474                 target_put_nacl(se_nacl);
 475         }
 476         if (se_sess->sess_cmd_map) {
 477                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 478                 kvfree(se_sess->sess_cmd_map);
 479         }
 480         kmem_cache_free(se_sess_cache, se_sess);
 481 }
 482 EXPORT_SYMBOL(transport_free_session);
 483
 484 void transport_deregister_session(struct se_session *se_sess)
 485 {
 486         struct se_portal_group *se_tpg = se_sess->se_tpg;
 487         const struct target_core_fabric_ops *se_tfo;
 488         struct se_node_acl *se_nacl;
 489         unsigned long flags;
 490         bool drop_nacl = false;
 491
 492         if (!se_tpg) {
 493                 transport_free_session(se_sess);
 494                 return;
 495         }
 496         se_tfo = se_tpg->se_tpg_tfo;
 497
 498         spin_lock_irqsave(&se_tpg->session_lock, flags);
 499         list_del(&se_sess->sess_list);
 500         se_sess->se_tpg = NULL;
 501         se_sess->fabric_sess_ptr = NULL;
 502         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 503
 504         /*
 505          * Determine if we need to do extra work for this initiator node's
 506          * struct se_node_acl if it had been previously dynamically generated.
 507          */
 508         se_nacl = se_sess->se_node_acl;
 509
 510         mutex_lock(&se_tpg->acl_node_mutex);
 511         if (se_nacl && se_nacl->dynamic_node_acl) {
 512                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 513                         list_del(&se_nacl->acl_list);
 514                         se_tpg->num_node_acls--;
 515                         drop_nacl = true;
 516                 }
 517         }
 518         mutex_unlock(&se_tpg->acl_node_mutex);
 519
 520         if (drop_nacl) {
 521                 core_tpg_wait_for_nacl_pr_ref(se_nacl);
 522                 core_free_device_list_for_node(se_nacl, se_tpg);
 523                 se_sess->se_node_acl = NULL;
 524                 kfree(se_nacl);
 525         }
 526         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 527                 se_tpg->se_tpg_tfo->get_fabric_name());
 528         /*
 529          * If last kref is dropping now for an explicit NodeACL, awake sleeping
 530          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 531          * removal context from within transport_free_session() code.
 532          */
 533
 534         transport_free_session(se_sess);
 535 }
 536 EXPORT_SYMBOL(transport_deregister_session);
 537
 538 static void target_remove_from_state_list(struct se_cmd *cmd)
 539 {
 540         struct se_device *dev = cmd->se_dev;
 541         unsigned long flags;
 542
 543         if (!dev)
 544                 return;
 545
 546         if (cmd->transport_state & CMD_T_BUSY)
 547                 return;
 548
 549         spin_lock_irqsave(&dev->execute_task_lock, flags);
 550         if (cmd->state_active) {
 551                 list_del(&cmd->state_list);
 552                 cmd->state_active = false;
 553         }
 554         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 555 }
 556
 557 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 558                                     bool write_pending)
 559 {
 560         unsigned long flags;
 561
 562         if (remove_from_lists) {
 563                 target_remove_from_state_list(cmd);
 564
 565                 /*
 566                  * Clear struct se_cmd->se_lun before the handoff to FE.
 567                  */
 568                 cmd->se_lun = NULL;
 569         }
 570
 571         spin_lock_irqsave(&cmd->t_state_lock, flags);
 572         if (write_pending)
 573                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 574
 575         /*
 576          * Determine if frontend context caller is requesting the stopping of
 577          * this command for frontend exceptions.
 578          */
 579         if (cmd->transport_state & CMD_T_STOP) {
 580                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
 581                         __func__, __LINE__, cmd->tag);
 582
 583                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 584
 585                 complete_all(&cmd->t_transport_stop_comp);
 586                 return 1;
 587         }
 588
 589         cmd->transport_state &= ~CMD_T_ACTIVE;
 590         if (remove_from_lists) {
 591                 /*
 592                  * Some fabric modules like tcm_loop can release
 593                  * their internally allocated I/O reference now and
 594                  * struct se_cmd now.
 595                  *
 596                  * Fabric modules are expected to return '1' here if the
 597                  * se_cmd being passed is released at this point,
 598                  * or zero if not being released.
 599                  */
 600                 if (cmd->se_tfo->check_stop_free != NULL) {
 601                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 602                         return cmd->se_tfo->check_stop_free(cmd);
 603                 }
 604         }
 605
 606         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 607         return 0;
 608 }
 609
 610 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 611 {
 612         return transport_cmd_check_stop(cmd, true, false);
 613 }
 614
 615 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 616 {
 617         struct se_lun *lun = cmd->se_lun;
 618
 619         if (!lun)
 620                 return;
 621
 622         if (cmpxchg(&cmd->lun_ref_active, true, false))
 623                 percpu_ref_put(&lun->lun_ref);
 624 }
 625
 626 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 627 {
 628         bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF);
 629
 630         if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
 631                 transport_lun_remove_cmd(cmd);
 632         /*
 633          * Allow the fabric driver to unmap any resources before
 634          * releasing the descriptor via TFO->release_cmd()
 635          */
 636         if (remove)
 637                 cmd->se_tfo->aborted_task(cmd);
 638
 639         if (transport_cmd_check_stop_to_fabric(cmd))
 640                 return;
 641         if (remove && ack_kref)
 642                 transport_put_cmd(cmd);
 643 }
 644
 645 static void target_complete_failure_work(struct work_struct *work)
 646 {
 647         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 648
 649         transport_generic_request_failure(cmd,
 650                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 651 }
 652
 653 /*
 654  * Used when asking transport to copy Sense Data from the underlying
 655  * Linux/SCSI struct scsi_cmnd
 656  */
 657 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 658 {
 659         struct se_device *dev = cmd->se_dev;
 660
 661         WARN_ON(!cmd->se_lun);
 662
 663         if (!dev)
 664                 return NULL;
 665
 666         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 667                 return NULL;
 668
 669         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 670
 671         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 672                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 673         return cmd->sense_buffer;
 674 }
 675
 676 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 677 {
 678         struct se_device *dev = cmd->se_dev;
 679         int success = scsi_status == GOOD;
 680         unsigned long flags;
 681
 682         cmd->scsi_status = scsi_status;
 683
 684
 685         spin_lock_irqsave(&cmd->t_state_lock, flags);
 686         cmd->transport_state &= ~CMD_T_BUSY;
 687
 688         if (dev && dev->transport->transport_complete) {
 689                 dev->transport->transport_complete(cmd,
 690                                 cmd->t_data_sg,
 691                                 transport_get_sense_buffer(cmd));
 692                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 693                         success = 1;
 694         }
 695
 696         /*
 697          * See if we are waiting to complete for an exception condition.
 698          */
 699         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
 700                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 701                 complete(&cmd->task_stop_comp);
 702                 return;
 703         }
 704
 705         /*
 706          * Check for case where an explicit ABORT_TASK has been received
 707          * and transport_wait_for_tasks() will be waiting for completion..
 708          */
 709         if (cmd->transport_state & CMD_T_ABORTED ||
 710             cmd->transport_state & CMD_T_STOP) {
 711                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 712                 complete_all(&cmd->t_transport_stop_comp);
 713                 return;
 714         } else if (!success) {
 715                 INIT_WORK(&cmd->work, target_complete_failure_work);
 716         } else {
 717                 INIT_WORK(&cmd->work, target_complete_ok_work);
 718         }
 719
 720         cmd->t_state = TRANSPORT_COMPLETE;
 721         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 722         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 723
 724         queue_work(target_completion_wq, &cmd->work);
 725 }
 726 EXPORT_SYMBOL(target_complete_cmd);
 727
 728 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 729 {
 730         if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
 731                 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 732                         cmd->residual_count += cmd->data_length - length;
 733                 } else {
 734                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
 735                         cmd->residual_count = cmd->data_length - length;
 736                 }
 737
 738                 cmd->data_length = length;
 739         }
 740
 741         target_complete_cmd(cmd, scsi_status);
 742 }
 743 EXPORT_SYMBOL(target_complete_cmd_with_length);
 744
 745 static void target_add_to_state_list(struct se_cmd *cmd)
 746 {
 747         struct se_device *dev = cmd->se_dev;
 748         unsigned long flags;
 749
 750         spin_lock_irqsave(&dev->execute_task_lock, flags);
 751         if (!cmd->state_active) {
 752                 list_add_tail(&cmd->state_list, &dev->state_list);
 753                 cmd->state_active = true;
 754         }
 755         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 756 }
 757
 758 /*
 759  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 760  */
 761 static void transport_write_pending_qf(struct se_cmd *cmd);
 762 static void transport_complete_qf(struct se_cmd *cmd);
 763
 764 void target_qf_do_work(struct work_struct *work)
 765 {
 766         struct se_device *dev = container_of(work, struct se_device,
 767                                         qf_work_queue);
 768         LIST_HEAD(qf_cmd_list);
 769         struct se_cmd *cmd, *cmd_tmp;
 770
 771         spin_lock_irq(&dev->qf_cmd_lock);
 772         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 773         spin_unlock_irq(&dev->qf_cmd_lock);
 774
 775         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 776                 list_del(&cmd->se_qf_node);
 777                 atomic_dec_mb(&dev->dev_qf_count);
 778
 779                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 780                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 781                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 782                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 783                         : "UNKNOWN");
 784
 785                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 786                         transport_write_pending_qf(cmd);
 787                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 788                         transport_complete_qf(cmd);
 789         }
 790 }
 791
 792 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 793 {
 794         switch (cmd->data_direction) {
 795         case DMA_NONE:
 796                 return "NONE";
 797         case DMA_FROM_DEVICE:
 798                 return "READ";
 799         case DMA_TO_DEVICE:
 800                 return "WRITE";
 801         case DMA_BIDIRECTIONAL:
 802                 return "BIDI";
 803         default:
 804                 break;
 805         }
 806
 807         return "UNKNOWN";
 808 }
 809
 810 void transport_dump_dev_state(
 811         struct se_device *dev,
 812         char *b,
 813         int *bl)
 814 {
 815         *bl += sprintf(b + *bl, "Status: ");
 816         if (dev->export_count)
 817                 *bl += sprintf(b + *bl, "ACTIVATED");
 818         else
 819                 *bl += sprintf(b + *bl, "DEACTIVATED");
 820
 821         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 822         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 823                 dev->dev_attrib.block_size,
 824                 dev->dev_attrib.hw_max_sectors);
 825         *bl += sprintf(b + *bl, "        ");
 826 }
 827
 828 void transport_dump_vpd_proto_id(
 829         struct t10_vpd *vpd,
 830         unsigned char *p_buf,
 831         int p_buf_len)
 832 {
 833         unsigned char buf[VPD_TMP_BUF_SIZE];
 834         int len;
 835
 836         memset(buf, 0, VPD_TMP_BUF_SIZE);
 837         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 838
 839         switch (vpd->protocol_identifier) {
 840         case 0x00:
 841                 sprintf(buf+len, "Fibre Channel\n");
 842                 break;
 843         case 0x10:
 844                 sprintf(buf+len, "Parallel SCSI\n");
 845                 break;
 846         case 0x20:
 847                 sprintf(buf+len, "SSA\n");
 848                 break;
 849         case 0x30:
 850                 sprintf(buf+len, "IEEE 1394\n");
 851                 break;
 852         case 0x40:
 853                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 854                                 " Protocol\n");
 855                 break;
 856         case 0x50:
 857                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 858                 break;
 859         case 0x60:
 860                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 861                 break;
 862         case 0x70:
 863                 sprintf(buf+len, "Automation/Drive Interface Transport"
 864                                 " Protocol\n");
 865                 break;
 866         case 0x80:
 867                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 868                 break;
 869         default:
 870                 sprintf(buf+len, "Unknown 0x%02x\n",
 871                                 vpd->protocol_identifier);
 872                 break;
 873         }
 874
 875         if (p_buf)
 876                 strncpy(p_buf, buf, p_buf_len);
 877         else
 878                 pr_debug("%s", buf);
 879 }
 880
 881 void
 882 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 883 {
 884         /*
 885          * Check if the Protocol Identifier Valid (PIV) bit is set..
 886          *
 887          * from spc3r23.pdf section 7.5.1
 888          */
 889          if (page_83[1] & 0x80) {
 890                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 891                 vpd->protocol_identifier_set = 1;
 892                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 893         }
 894 }
 895 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 896
 897 int transport_dump_vpd_assoc(
 898         struct t10_vpd *vpd,
 899         unsigned char *p_buf,
 900         int p_buf_len)
 901 {
 902         unsigned char buf[VPD_TMP_BUF_SIZE];
 903         int ret = 0;
 904         int len;
 905
 906         memset(buf, 0, VPD_TMP_BUF_SIZE);
 907         len = sprintf(buf, "T10 VPD Identifier Association: ");
 908
 909         switch (vpd->association) {
 910         case 0x00:
 911                 sprintf(buf+len, "addressed logical unit\n");
 912                 break;
 913         case 0x10:
 914                 sprintf(buf+len, "target port\n");
 915                 break;
 916         case 0x20:
 917                 sprintf(buf+len, "SCSI target device\n");
 918                 break;
 919         default:
 920                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 921                 ret = -EINVAL;
 922                 break;
 923         }
 924
 925         if (p_buf)
 926                 strncpy(p_buf, buf, p_buf_len);
 927         else
 928                 pr_debug("%s", buf);
 929
 930         return ret;
 931 }
 932
 933 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 934 {
 935         /*
 936          * The VPD identification association..
 937          *
 938          * from spc3r23.pdf Section 7.6.3.1 Table 297
 939          */
 940         vpd->association = (page_83[1] & 0x30);
 941         return transport_dump_vpd_assoc(vpd, NULL, 0);
 942 }
 943 EXPORT_SYMBOL(transport_set_vpd_assoc);
 944
 945 int transport_dump_vpd_ident_type(
 946         struct t10_vpd *vpd,
 947         unsigned char *p_buf,
 948         int p_buf_len)
 949 {
 950         unsigned char buf[VPD_TMP_BUF_SIZE];
 951         int ret = 0;
 952         int len;
 953
 954         memset(buf, 0, VPD_TMP_BUF_SIZE);
 955         len = sprintf(buf, "T10 VPD Identifier Type: ");
 956
 957         switch (vpd->device_identifier_type) {
 958         case 0x00:
 959                 sprintf(buf+len, "Vendor specific\n");
 960                 break;
 961         case 0x01:
 962                 sprintf(buf+len, "T10 Vendor ID based\n");
 963                 break;
 964         case 0x02:
 965                 sprintf(buf+len, "EUI-64 based\n");
 966                 break;
 967         case 0x03:
 968                 sprintf(buf+len, "NAA\n");
 969                 break;
 970         case 0x04:
 971                 sprintf(buf+len, "Relative target port identifier\n");
 972                 break;
 973         case 0x08:
 974                 sprintf(buf+len, "SCSI name string\n");
 975                 break;
 976         default:
 977                 sprintf(buf+len, "Unsupported: 0x%02x\n",
 978                                 vpd->device_identifier_type);
 979                 ret = -EINVAL;
 980                 break;
 981         }
 982
 983         if (p_buf) {
 984                 if (p_buf_len < strlen(buf)+1)
 985                         return -EINVAL;
 986                 strncpy(p_buf, buf, p_buf_len);
 987         } else {
 988                 pr_debug("%s", buf);
 989         }
 990
 991         return ret;
 992 }
 993
 994 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
 995 {
 996         /*
 997          * The VPD identifier type..
 998          *
 999          * from spc3r23.pdf Section 7.6.3.1 Table 298
1000          */
1001         vpd->device_identifier_type = (page_83[1] & 0x0f);
1002         return transport_dump_vpd_ident_type(vpd, NULL, 0);
1003 }
1004 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1005
1006 int transport_dump_vpd_ident(
1007         struct t10_vpd *vpd,
1008         unsigned char *p_buf,
1009         int p_buf_len)
1010 {
1011         unsigned char buf[VPD_TMP_BUF_SIZE];
1012         int ret = 0;
1013
1014         memset(buf, 0, VPD_TMP_BUF_SIZE);
1015
1016         switch (vpd->device_identifier_code_set) {
1017         case 0x01: /* Binary */
1018                 snprintf(buf, sizeof(buf),
1019                         "T10 VPD Binary Device Identifier: %s\n",
1020                         &vpd->device_identifier[0]);
1021                 break;
1022         case 0x02: /* ASCII */
1023                 snprintf(buf, sizeof(buf),
1024                         "T10 VPD ASCII Device Identifier: %s\n",
1025                         &vpd->device_identifier[0]);
1026                 break;
1027         case 0x03: /* UTF-8 */
1028                 snprintf(buf, sizeof(buf),
1029                         "T10 VPD UTF-8 Device Identifier: %s\n",
1030                         &vpd->device_identifier[0]);
1031                 break;
1032         default:
1033                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1034                         " 0x%02x", vpd->device_identifier_code_set);
1035                 ret = -EINVAL;
1036                 break;
1037         }
1038
1039         if (p_buf)
1040                 strncpy(p_buf, buf, p_buf_len);
1041         else
1042                 pr_debug("%s", buf);
1043
1044         return ret;
1045 }
1046
1047 int
1048 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1049 {
1050         static const char hex_str[] = "0123456789abcdef";
1051         int j = 0, i = 4; /* offset to start of the identifier */
1052
1053         /*
1054          * The VPD Code Set (encoding)
1055          *
1056          * from spc3r23.pdf Section 7.6.3.1 Table 296
1057          */
1058         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1059         switch (vpd->device_identifier_code_set) {
1060         case 0x01: /* Binary */
1061                 vpd->device_identifier[j++] =
1062                                 hex_str[vpd->device_identifier_type];
1063                 while (i < (4 + page_83[3])) {
1064                         vpd->device_identifier[j++] =
1065                                 hex_str[(page_83[i] & 0xf0) >> 4];
1066                         vpd->device_identifier[j++] =
1067                                 hex_str[page_83[i] & 0x0f];
1068                         i++;
1069                 }
1070                 break;
1071         case 0x02: /* ASCII */
1072         case 0x03: /* UTF-8 */
1073                 while (i < (4 + page_83[3]))
1074                         vpd->device_identifier[j++] = page_83[i++];
1075                 break;
1076         default:
1077                 break;
1078         }
1079
1080         return transport_dump_vpd_ident(vpd, NULL, 0);
1081 }
1082 EXPORT_SYMBOL(transport_set_vpd_ident);
1083
1084 static sense_reason_t
1085 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1086                                unsigned int size)
1087 {
1088         u32 mtl;
1089
1090         if (!cmd->se_tfo->max_data_sg_nents)
1091                 return TCM_NO_SENSE;
1092         /*
1093          * Check if fabric enforced maximum SGL entries per I/O descriptor
1094          * exceeds se_cmd->data_length.  If true, set SCF_UNDERFLOW_BIT +
1095          * residual_count and reduce original cmd->data_length to maximum
1096          * length based on single PAGE_SIZE entry scatter-lists.
1097          */
1098         mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1099         if (cmd->data_length > mtl) {
1100                 /*
1101                  * If an existing CDB overflow is present, calculate new residual
1102                  * based on CDB size minus fabric maximum transfer length.
1103                  *
1104                  * If an existing CDB underflow is present, calculate new residual
1105                  * based on original cmd->data_length minus fabric maximum transfer
1106                  * length.
1107                  *
1108                  * Otherwise, set the underflow residual based on cmd->data_length
1109                  * minus fabric maximum transfer length.
1110                  */
1111                 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1112                         cmd->residual_count = (size - mtl);
1113                 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1114                         u32 orig_dl = size + cmd->residual_count;
1115                         cmd->residual_count = (orig_dl - mtl);
1116                 } else {
1117                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1118                         cmd->residual_count = (cmd->data_length - mtl);
1119                 }
1120                 cmd->data_length = mtl;
1121                 /*
1122                  * Reset sbc_check_prot() calculated protection payload
1123                  * length based upon the new smaller MTL.
1124                  */
1125                 if (cmd->prot_length) {
1126                         u32 sectors = (mtl / dev->dev_attrib.block_size);
1127                         cmd->prot_length = dev->prot_length * sectors;
1128                 }
1129         }
1130         return TCM_NO_SENSE;
1131 }
1132
1133 sense_reason_t
1134 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1135 {
1136         struct se_device *dev = cmd->se_dev;
1137
1138         if (cmd->unknown_data_length) {
1139                 cmd->data_length = size;
1140         } else if (size != cmd->data_length) {
1141                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1142                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1143                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1144                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1145
1146                 if (cmd->data_direction == DMA_TO_DEVICE &&
1147                     cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1148                         pr_err("Rejecting underflow/overflow WRITE data\n");
1149                         return TCM_INVALID_CDB_FIELD;
1150                 }
1151                 /*
1152                  * Reject READ_* or WRITE_* with overflow/underflow for
1153                  * type SCF_SCSI_DATA_CDB.
1154                  */
1155                 if (dev->dev_attrib.block_size != 512)  {
1156                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1157                                 " CDB on non 512-byte sector setup subsystem"
1158                                 " plugin: %s\n", dev->transport->name);
1159                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1160                         return TCM_INVALID_CDB_FIELD;
1161                 }
1162                 /*
1163                  * For the overflow case keep the existing fabric provided
1164                  * ->data_length.  Otherwise for the underflow case, reset
1165                  * ->data_length to the smaller SCSI expected data transfer
1166                  * length.
1167                  */
1168                 if (size > cmd->data_length) {
1169                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1170                         cmd->residual_count = (size - cmd->data_length);
1171                 } else {
1172                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1173                         cmd->residual_count = (cmd->data_length - size);
1174                         cmd->data_length = size;
1175                 }
1176         }
1177
1178         return target_check_max_data_sg_nents(cmd, dev, size);
1179
1180 }
1181
1182 /*
1183  * Used by fabric modules containing a local struct se_cmd within their
1184  * fabric dependent per I/O descriptor.
1185  *
1186  * Preserves the value of @cmd->tag.
1187  */
1188 void transport_init_se_cmd(
1189         struct se_cmd *cmd,
1190         const struct target_core_fabric_ops *tfo,
1191         struct se_session *se_sess,
1192         u32 data_length,
1193         int data_direction,
1194         int task_attr,
1195         unsigned char *sense_buffer)
1196 {
1197         INIT_LIST_HEAD(&cmd->se_delayed_node);
1198         INIT_LIST_HEAD(&cmd->se_qf_node);
1199         INIT_LIST_HEAD(&cmd->se_cmd_list);
1200         INIT_LIST_HEAD(&cmd->state_list);
1201         init_completion(&cmd->t_transport_stop_comp);
1202         init_completion(&cmd->cmd_wait_comp);
1203         init_completion(&cmd->task_stop_comp);
1204         spin_lock_init(&cmd->t_state_lock);
1205         kref_init(&cmd->cmd_kref);
1206         cmd->transport_state = CMD_T_DEV_ACTIVE;
1207
1208         cmd->se_tfo = tfo;
1209         cmd->se_sess = se_sess;
1210         cmd->data_length = data_length;
1211         cmd->data_direction = data_direction;
1212         cmd->sam_task_attr = task_attr;
1213         cmd->sense_buffer = sense_buffer;
1214
1215         cmd->state_active = false;
1216 }
1217 EXPORT_SYMBOL(transport_init_se_cmd);
1218
1219 static sense_reason_t
1220 transport_check_alloc_task_attr(struct se_cmd *cmd)
1221 {
1222         struct se_device *dev = cmd->se_dev;
1223
1224         /*
1225          * Check if SAM Task Attribute emulation is enabled for this
1226          * struct se_device storage object
1227          */
1228         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1229                 return 0;
1230
1231         if (cmd->sam_task_attr == TCM_ACA_TAG) {
1232                 pr_debug("SAM Task Attribute ACA"
1233                         " emulation is not supported\n");
1234                 return TCM_INVALID_CDB_FIELD;
1235         }
1236
1237         return 0;
1238 }
1239
1240 sense_reason_t
1241 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1242 {
1243         struct se_device *dev = cmd->se_dev;
1244         sense_reason_t ret;
1245
1246         /*
1247          * Ensure that the received CDB is less than the max (252 + 8) bytes
1248          * for VARIABLE_LENGTH_CMD
1249          */
1250         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1251                 pr_err("Received SCSI CDB with command_size: %d that"
1252                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1253                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1254                 return TCM_INVALID_CDB_FIELD;
1255         }
1256         /*
1257          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1258          * allocate the additional extended CDB buffer now..  Otherwise
1259          * setup the pointer from __t_task_cdb to t_task_cdb.
1260          */
1261         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1262                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1263                                                 GFP_KERNEL);
1264                 if (!cmd->t_task_cdb) {
1265                         pr_err("Unable to allocate cmd->t_task_cdb"
1266                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1267                                 scsi_command_size(cdb),
1268                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1269                         return TCM_OUT_OF_RESOURCES;
1270                 }
1271         } else
1272                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1273         /*
1274          * Copy the original CDB into cmd->
1275          */
1276         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1277
1278         trace_target_sequencer_start(cmd);
1279
1280         ret = dev->transport->parse_cdb(cmd);
1281         if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1282                 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1283                                     cmd->se_tfo->get_fabric_name(),
1284                                     cmd->se_sess->se_node_acl->initiatorname,
1285                                     cmd->t_task_cdb[0]);
1286         if (ret)
1287                 return ret;
1288
1289         ret = transport_check_alloc_task_attr(cmd);
1290         if (ret)
1291                 return ret;
1292
1293         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1294         atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1295         return 0;
1296 }
1297 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1298
1299 /*
1300  * Used by fabric module frontends to queue tasks directly.
1301  * Many only be used from process context only
1302  */
1303 int transport_handle_cdb_direct(
1304         struct se_cmd *cmd)
1305 {
1306         sense_reason_t ret;
1307
1308         if (!cmd->se_lun) {
1309                 dump_stack();
1310                 pr_err("cmd->se_lun is NULL\n");
1311                 return -EINVAL;
1312         }
1313         if (in_interrupt()) {
1314                 dump_stack();
1315                 pr_err("transport_generic_handle_cdb cannot be called"
1316                                 " from interrupt context\n");
1317                 return -EINVAL;
1318         }
1319         /*
1320          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1321          * outstanding descriptors are handled correctly during shutdown via
1322          * transport_wait_for_tasks()
1323          *
1324          * Also, we don't take cmd->t_state_lock here as we only expect
1325          * this to be called for initial descriptor submission.
1326          */
1327         cmd->t_state = TRANSPORT_NEW_CMD;
1328         cmd->transport_state |= CMD_T_ACTIVE;
1329
1330         /*
1331          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1332          * so follow TRANSPORT_NEW_CMD processing thread context usage
1333          * and call transport_generic_request_failure() if necessary..
1334          */
1335         ret = transport_generic_new_cmd(cmd);
1336         if (ret)
1337                 transport_generic_request_failure(cmd, ret);
1338         return 0;
1339 }
1340 EXPORT_SYMBOL(transport_handle_cdb_direct);
1341
1342 sense_reason_t
1343 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1344                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1345 {
1346         if (!sgl || !sgl_count)
1347                 return 0;
1348
1349         /*
1350          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1351          * scatterlists already have been set to follow what the fabric
1352          * passes for the original expected data transfer length.
1353          */
1354         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1355                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1356                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1357                 return TCM_INVALID_CDB_FIELD;
1358         }
1359
1360         cmd->t_data_sg = sgl;
1361         cmd->t_data_nents = sgl_count;
1362         cmd->t_bidi_data_sg = sgl_bidi;
1363         cmd->t_bidi_data_nents = sgl_bidi_count;
1364
1365         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1366         return 0;
1367 }
1368
1369 /*
1370  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1371  *                       se_cmd + use pre-allocated SGL memory.
1372  *
1373  * @se_cmd: command descriptor to submit
1374  * @se_sess: associated se_sess for endpoint
1375  * @cdb: pointer to SCSI CDB
1376  * @sense: pointer to SCSI sense buffer
1377  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1378  * @data_length: fabric expected data transfer length
1379  * @task_addr: SAM task attribute
1380  * @data_dir: DMA data direction
1381  * @flags: flags for command submission from target_sc_flags_tables
1382  * @sgl: struct scatterlist memory for unidirectional mapping
1383  * @sgl_count: scatterlist count for unidirectional mapping
1384  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1385  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1386  * @sgl_prot: struct scatterlist memory protection information
1387  * @sgl_prot_count: scatterlist count for protection information
1388  *
1389  * Task tags are supported if the caller has set @se_cmd->tag.
1390  *
1391  * Returns non zero to signal active I/O shutdown failure.  All other
1392  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1393  * but still return zero here.
1394  *
1395  * This may only be called from process context, and also currently
1396  * assumes internal allocation of fabric payload buffer by target-core.
1397  */
1398 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1399                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1400                 u32 data_length, int task_attr, int data_dir, int flags,
1401                 struct scatterlist *sgl, u32 sgl_count,
1402                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1403                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1404 {
1405         struct se_portal_group *se_tpg;
1406         sense_reason_t rc;
1407         int ret;
1408
1409         se_tpg = se_sess->se_tpg;
1410         BUG_ON(!se_tpg);
1411         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1412         BUG_ON(in_interrupt());
1413         /*
1414          * Initialize se_cmd for target operation.  From this point
1415          * exceptions are handled by sending exception status via
1416          * target_core_fabric_ops->queue_status() callback
1417          */
1418         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1419                                 data_length, data_dir, task_attr, sense);
1420         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1421                 se_cmd->unknown_data_length = 1;
1422         /*
1423          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1424          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1425          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1426          * kref_put() to happen during fabric packet acknowledgement.
1427          */
1428         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1429         if (ret)
1430                 return ret;
1431         /*
1432          * Signal bidirectional data payloads to target-core
1433          */
1434         if (flags & TARGET_SCF_BIDI_OP)
1435                 se_cmd->se_cmd_flags |= SCF_BIDI;
1436         /*
1437          * Locate se_lun pointer and attach it to struct se_cmd
1438          */
1439         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1440         if (rc) {
1441                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1442                 target_put_sess_cmd(se_cmd);
1443                 return 0;
1444         }
1445
1446         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1447         if (rc != 0) {
1448                 transport_generic_request_failure(se_cmd, rc);
1449                 return 0;
1450         }
1451
1452         /*
1453          * Save pointers for SGLs containing protection information,
1454          * if present.
1455          */
1456         if (sgl_prot_count) {
1457                 se_cmd->t_prot_sg = sgl_prot;
1458                 se_cmd->t_prot_nents = sgl_prot_count;
1459                 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1460         }
1461
1462         /*
1463          * When a non zero sgl_count has been passed perform SGL passthrough
1464          * mapping for pre-allocated fabric memory instead of having target
1465          * core perform an internal SGL allocation..
1466          */
1467         if (sgl_count != 0) {
1468                 BUG_ON(!sgl);
1469
1470                 /*
1471                  * A work-around for tcm_loop as some userspace code via
1472                  * scsi-generic do not memset their associated read buffers,
1473                  * so go ahead and do that here for type non-data CDBs.  Also
1474                  * note that this is currently guaranteed to be a single SGL
1475                  * for this case by target core in target_setup_cmd_from_cdb()
1476                  * -> transport_generic_cmd_sequencer().
1477                  */
1478                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1479                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1480                         unsigned char *buf = NULL;
1481
1482                         if (sgl)
1483                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1484
1485                         if (buf) {
1486                                 memset(buf, 0, sgl->length);
1487                                 kunmap(sg_page(sgl));
1488                         }
1489                 }
1490
1491                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1492                                 sgl_bidi, sgl_bidi_count);
1493                 if (rc != 0) {
1494                         transport_generic_request_failure(se_cmd, rc);
1495                         return 0;
1496                 }
1497         }
1498
1499         /*
1500          * Check if we need to delay processing because of ALUA
1501          * Active/NonOptimized primary access state..
1502          */
1503         core_alua_check_nonop_delay(se_cmd);
1504
1505         transport_handle_cdb_direct(se_cmd);
1506         return 0;
1507 }
1508 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1509
1510 /*
1511  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1512  *
1513  * @se_cmd: command descriptor to submit
1514  * @se_sess: associated se_sess for endpoint
1515  * @cdb: pointer to SCSI CDB
1516  * @sense: pointer to SCSI sense buffer
1517  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1518  * @data_length: fabric expected data transfer length
1519  * @task_addr: SAM task attribute
1520  * @data_dir: DMA data direction
1521  * @flags: flags for command submission from target_sc_flags_tables
1522  *
1523  * Task tags are supported if the caller has set @se_cmd->tag.
1524  *
1525  * Returns non zero to signal active I/O shutdown failure.  All other
1526  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1527  * but still return zero here.
1528  *
1529  * This may only be called from process context, and also currently
1530  * assumes internal allocation of fabric payload buffer by target-core.
1531  *
1532  * It also assumes interal target core SGL memory allocation.
1533  */
1534 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1535                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1536                 u32 data_length, int task_attr, int data_dir, int flags)
1537 {
1538         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1539                         unpacked_lun, data_length, task_attr, data_dir,
1540                         flags, NULL, 0, NULL, 0, NULL, 0);
1541 }
1542 EXPORT_SYMBOL(target_submit_cmd);
1543
1544 static void target_complete_tmr_failure(struct work_struct *work)
1545 {
1546         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1547
1548         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1549         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1550
1551         transport_cmd_check_stop_to_fabric(se_cmd);
1552 }
1553
1554 /**
1555  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1556  *                     for TMR CDBs
1557  *
1558  * @se_cmd: command descriptor to submit
1559  * @se_sess: associated se_sess for endpoint
1560  * @sense: pointer to SCSI sense buffer
1561  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1562  * @fabric_context: fabric context for TMR req
1563  * @tm_type: Type of TM request
1564  * @gfp: gfp type for caller
1565  * @tag: referenced task tag for TMR_ABORT_TASK
1566  * @flags: submit cmd flags
1567  *
1568  * Callable from all contexts.
1569  **/
1570
1571 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1572                 unsigned char *sense, u64 unpacked_lun,
1573                 void *fabric_tmr_ptr, unsigned char tm_type,
1574                 gfp_t gfp, unsigned int tag, int flags)
1575 {
1576         struct se_portal_group *se_tpg;
1577         int ret;
1578
1579         se_tpg = se_sess->se_tpg;
1580         BUG_ON(!se_tpg);
1581
1582         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1583                               0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1584         /*
1585          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1586          * allocation failure.
1587          */
1588         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1589         if (ret < 0)
1590                 return -ENOMEM;
1591
1592         if (tm_type == TMR_ABORT_TASK)
1593                 se_cmd->se_tmr_req->ref_task_tag = tag;
1594
1595         /* See target_submit_cmd for commentary */
1596         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1597         if (ret) {
1598                 core_tmr_release_req(se_cmd->se_tmr_req);
1599                 return ret;
1600         }
1601
1602         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1603         if (ret) {
1604                 /*
1605                  * For callback during failure handling, push this work off
1606                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1607                  */
1608                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1609                 schedule_work(&se_cmd->work);
1610                 return 0;
1611         }
1612         transport_generic_handle_tmr(se_cmd);
1613         return 0;
1614 }
1615 EXPORT_SYMBOL(target_submit_tmr);
1616
1617 /*
1618  * If the cmd is active, request it to be stopped and sleep until it
1619  * has completed.
1620  */
1621 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1622         __releases(&cmd->t_state_lock)
1623         __acquires(&cmd->t_state_lock)
1624 {
1625         bool was_active = false;
1626
1627         if (cmd->transport_state & CMD_T_BUSY) {
1628                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1629                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1630
1631                 pr_debug("cmd %p waiting to complete\n", cmd);
1632                 wait_for_completion(&cmd->task_stop_comp);
1633                 pr_debug("cmd %p stopped successfully\n", cmd);
1634
1635                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1636                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1637                 cmd->transport_state &= ~CMD_T_BUSY;
1638                 was_active = true;
1639         }
1640
1641         return was_active;
1642 }
1643
1644 /*
1645  * Handle SAM-esque emulation for generic transport request failures.
1646  */
1647 void transport_generic_request_failure(struct se_cmd *cmd,
1648                 sense_reason_t sense_reason)
1649 {
1650         int ret = 0, post_ret = 0;
1651
1652         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08llx"
1653                 " CDB: 0x%02x\n", cmd, cmd->tag, cmd->t_task_cdb[0]);
1654         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1655                 cmd->se_tfo->get_cmd_state(cmd),
1656                 cmd->t_state, sense_reason);
1657         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1658                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1659                 (cmd->transport_state & CMD_T_STOP) != 0,
1660                 (cmd->transport_state & CMD_T_SENT) != 0);
1661
1662         /*
1663          * For SAM Task Attribute emulation for failed struct se_cmd
1664          */
1665         transport_complete_task_attr(cmd);
1666         /*
1667          * Handle special case for COMPARE_AND_WRITE failure, where the
1668          * callback is expected to drop the per device ->caw_sem.
1669          */
1670         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1671              cmd->transport_complete_callback)
1672                 cmd->transport_complete_callback(cmd, false, &post_ret);
1673
1674         switch (sense_reason) {
1675         case TCM_NON_EXISTENT_LUN:
1676         case TCM_UNSUPPORTED_SCSI_OPCODE:
1677         case TCM_INVALID_CDB_FIELD:
1678         case TCM_INVALID_PARAMETER_LIST:
1679         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1680         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1681         case TCM_UNKNOWN_MODE_PAGE:
1682         case TCM_WRITE_PROTECTED:
1683         case TCM_ADDRESS_OUT_OF_RANGE:
1684         case TCM_CHECK_CONDITION_ABORT_CMD:
1685         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1686         case TCM_CHECK_CONDITION_NOT_READY:
1687         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1688         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1689         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1690         case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1691                 break;
1692         case TCM_OUT_OF_RESOURCES:
1693                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1694                 break;
1695         case TCM_RESERVATION_CONFLICT:
1696                 /*
1697                  * No SENSE Data payload for this case, set SCSI Status
1698                  * and queue the response to $FABRIC_MOD.
1699                  *
1700                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1701                  */
1702                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1703                 /*
1704                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1705                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1706                  * CONFLICT STATUS.
1707                  *
1708                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1709                  */
1710                 if (cmd->se_sess &&
1711                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1712                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1713                                                cmd->orig_fe_lun, 0x2C,
1714                                         ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1715                 }
1716                 trace_target_cmd_complete(cmd);
1717                 ret = cmd->se_tfo->queue_status(cmd);
1718                 if (ret == -EAGAIN || ret == -ENOMEM)
1719                         goto queue_full;
1720                 goto check_stop;
1721         default:
1722                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1723                         cmd->t_task_cdb[0], sense_reason);
1724                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1725                 break;
1726         }
1727
1728         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1729         if (ret == -EAGAIN || ret == -ENOMEM)
1730                 goto queue_full;
1731
1732 check_stop:
1733         transport_lun_remove_cmd(cmd);
1734         transport_cmd_check_stop_to_fabric(cmd);
1735         return;
1736
1737 queue_full:
1738         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1739         transport_handle_queue_full(cmd, cmd->se_dev);
1740 }
1741 EXPORT_SYMBOL(transport_generic_request_failure);
1742
1743 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1744 {
1745         sense_reason_t ret;
1746
1747         if (!cmd->execute_cmd) {
1748                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1749                 goto err;
1750         }
1751         if (do_checks) {
1752                 /*
1753                  * Check for an existing UNIT ATTENTION condition after
1754                  * target_handle_task_attr() has done SAM task attr
1755                  * checking, and possibly have already defered execution
1756                  * out to target_restart_delayed_cmds() context.
1757                  */
1758                 ret = target_scsi3_ua_check(cmd);
1759                 if (ret)
1760                         goto err;
1761
1762                 ret = target_alua_state_check(cmd);
1763                 if (ret)
1764                         goto err;
1765
1766                 ret = target_check_reservation(cmd);
1767                 if (ret) {
1768                         cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1769                         goto err;
1770                 }
1771         }
1772
1773         ret = cmd->execute_cmd(cmd);
1774         if (!ret)
1775                 return;
1776 err:
1777         spin_lock_irq(&cmd->t_state_lock);
1778         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1779         spin_unlock_irq(&cmd->t_state_lock);
1780
1781         transport_generic_request_failure(cmd, ret);
1782 }
1783
1784 static int target_write_prot_action(struct se_cmd *cmd)
1785 {
1786         u32 sectors;
1787         /*
1788          * Perform WRITE_INSERT of PI using software emulation when backend
1789          * device has PI enabled, if the transport has not already generated
1790          * PI using hardware WRITE_INSERT offload.
1791          */
1792         switch (cmd->prot_op) {
1793         case TARGET_PROT_DOUT_INSERT:
1794                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1795                         sbc_dif_generate(cmd);
1796                 break;
1797         case TARGET_PROT_DOUT_STRIP:
1798                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1799                         break;
1800
1801                 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1802                 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1803                                              sectors, 0, cmd->t_prot_sg, 0);
1804                 if (unlikely(cmd->pi_err)) {
1805                         spin_lock_irq(&cmd->t_state_lock);
1806                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1807                         spin_unlock_irq(&cmd->t_state_lock);
1808                         transport_generic_request_failure(cmd, cmd->pi_err);
1809                         return -1;
1810                 }
1811                 break;
1812         default:
1813                 break;
1814         }
1815
1816         return 0;
1817 }
1818
1819 static bool target_handle_task_attr(struct se_cmd *cmd)
1820 {
1821         struct se_device *dev = cmd->se_dev;
1822
1823         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1824                 return false;
1825
1826         cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
1827
1828         /*
1829          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1830          * to allow the passed struct se_cmd list of tasks to the front of the list.
1831          */
1832         switch (cmd->sam_task_attr) {
1833         case TCM_HEAD_TAG:
1834                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1835                          cmd->t_task_cdb[0]);
1836                 return false;
1837         case TCM_ORDERED_TAG:
1838                 atomic_inc_mb(&dev->dev_ordered_sync);
1839
1840                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1841                          cmd->t_task_cdb[0]);
1842
1843                 /*
1844                  * Execute an ORDERED command if no other older commands
1845                  * exist that need to be completed first.
1846                  */
1847                 if (!atomic_read(&dev->simple_cmds))
1848                         return false;
1849                 break;
1850         default:
1851                 /*
1852                  * For SIMPLE and UNTAGGED Task Attribute commands
1853                  */
1854                 atomic_inc_mb(&dev->simple_cmds);
1855                 break;
1856         }
1857
1858         if (atomic_read(&dev->dev_ordered_sync) == 0)
1859                 return false;
1860
1861         spin_lock(&dev->delayed_cmd_lock);
1862         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1863         spin_unlock(&dev->delayed_cmd_lock);
1864
1865         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
1866                 cmd->t_task_cdb[0], cmd->sam_task_attr);
1867         return true;
1868 }
1869
1870 static int __transport_check_aborted_status(struct se_cmd *, int);
1871
1872 void target_execute_cmd(struct se_cmd *cmd)
1873 {
1874         /*
1875          * Determine if frontend context caller is requesting the stopping of
1876          * this command for frontend exceptions.
1877          *
1878          * If the received CDB has aleady been aborted stop processing it here.
1879          */
1880         spin_lock_irq(&cmd->t_state_lock);
1881         if (__transport_check_aborted_status(cmd, 1)) {
1882                 spin_unlock_irq(&cmd->t_state_lock);
1883                 return;
1884         }
1885         if (cmd->transport_state & CMD_T_STOP) {
1886                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1887                         __func__, __LINE__, cmd->tag);
1888
1889                 spin_unlock_irq(&cmd->t_state_lock);
1890                 complete_all(&cmd->t_transport_stop_comp);
1891                 return;
1892         }
1893
1894         cmd->t_state = TRANSPORT_PROCESSING;
1895         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1896         spin_unlock_irq(&cmd->t_state_lock);
1897
1898         if (target_write_prot_action(cmd))
1899                 return;
1900
1901         if (target_handle_task_attr(cmd)) {
1902                 spin_lock_irq(&cmd->t_state_lock);
1903                 cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1904                 spin_unlock_irq(&cmd->t_state_lock);
1905                 return;
1906         }
1907
1908         __target_execute_cmd(cmd, true);
1909 }
1910 EXPORT_SYMBOL(target_execute_cmd);
1911
1912 /*
1913  * Process all commands up to the last received ORDERED task attribute which
1914  * requires another blocking boundary
1915  */
1916 static void target_restart_delayed_cmds(struct se_device *dev)
1917 {
1918         for (;;) {
1919                 struct se_cmd *cmd;
1920
1921                 spin_lock(&dev->delayed_cmd_lock);
1922                 if (list_empty(&dev->delayed_cmd_list)) {
1923                         spin_unlock(&dev->delayed_cmd_lock);
1924                         break;
1925                 }
1926
1927                 cmd = list_entry(dev->delayed_cmd_list.next,
1928                                  struct se_cmd, se_delayed_node);
1929                 list_del(&cmd->se_delayed_node);
1930                 spin_unlock(&dev->delayed_cmd_lock);
1931
1932                 __target_execute_cmd(cmd, true);
1933
1934                 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1935                         break;
1936         }
1937 }
1938
1939 /*
1940  * Called from I/O completion to determine which dormant/delayed
1941  * and ordered cmds need to have their tasks added to the execution queue.
1942  */
1943 static void transport_complete_task_attr(struct se_cmd *cmd)
1944 {
1945         struct se_device *dev = cmd->se_dev;
1946
1947         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1948                 return;
1949
1950         if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
1951                 goto restart;
1952
1953         if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1954                 atomic_dec_mb(&dev->simple_cmds);
1955                 dev->dev_cur_ordered_id++;
1956                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for SIMPLE\n",
1957                          dev->dev_cur_ordered_id);
1958         } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1959                 dev->dev_cur_ordered_id++;
1960                 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
1961                          dev->dev_cur_ordered_id);
1962         } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1963                 atomic_dec_mb(&dev->dev_ordered_sync);
1964
1965                 dev->dev_cur_ordered_id++;
1966                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
1967                          dev->dev_cur_ordered_id);
1968         }
1969 restart:
1970         target_restart_delayed_cmds(dev);
1971 }
1972
1973 static void transport_complete_qf(struct se_cmd *cmd)
1974 {
1975         int ret = 0;
1976
1977         transport_complete_task_attr(cmd);
1978
1979         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1980                 trace_target_cmd_complete(cmd);
1981                 ret = cmd->se_tfo->queue_status(cmd);
1982                 goto out;
1983         }
1984
1985         switch (cmd->data_direction) {
1986         case DMA_FROM_DEVICE:
1987                 trace_target_cmd_complete(cmd);
1988                 ret = cmd->se_tfo->queue_data_in(cmd);
1989                 break;
1990         case DMA_TO_DEVICE:
1991                 if (cmd->se_cmd_flags & SCF_BIDI) {
1992                         ret = cmd->se_tfo->queue_data_in(cmd);
1993                         break;
1994                 }
1995                 /* Fall through for DMA_TO_DEVICE */
1996         case DMA_NONE:
1997                 trace_target_cmd_complete(cmd);
1998                 ret = cmd->se_tfo->queue_status(cmd);
1999                 break;
2000         default:
2001                 break;
2002         }
2003
2004 out:
2005         if (ret < 0) {
2006                 transport_handle_queue_full(cmd, cmd->se_dev);
2007                 return;
2008         }
2009         transport_lun_remove_cmd(cmd);
2010         transport_cmd_check_stop_to_fabric(cmd);
2011 }
2012
2013 static void transport_handle_queue_full(
2014         struct se_cmd *cmd,
2015         struct se_device *dev)
2016 {
2017         spin_lock_irq(&dev->qf_cmd_lock);
2018         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2019         atomic_inc_mb(&dev->dev_qf_count);
2020         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2021
2022         schedule_work(&cmd->se_dev->qf_work_queue);
2023 }
2024
2025 static bool target_read_prot_action(struct se_cmd *cmd)
2026 {
2027         switch (cmd->prot_op) {
2028         case TARGET_PROT_DIN_STRIP:
2029                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2030                         u32 sectors = cmd->data_length >>
2031                                   ilog2(cmd->se_dev->dev_attrib.block_size);
2032
2033                         cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2034                                                      sectors, 0, cmd->t_prot_sg,
2035                                                      0);
2036                         if (cmd->pi_err)
2037                                 return true;
2038                 }
2039                 break;
2040         case TARGET_PROT_DIN_INSERT:
2041                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2042                         break;
2043
2044                 sbc_dif_generate(cmd);
2045                 break;
2046         default:
2047                 break;
2048         }
2049
2050         return false;
2051 }
2052
2053 static void target_complete_ok_work(struct work_struct *work)
2054 {
2055         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2056         int ret;
2057
2058         /*
2059          * Check if we need to move delayed/dormant tasks from cmds on the
2060          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2061          * Attribute.
2062          */
2063         transport_complete_task_attr(cmd);
2064
2065         /*
2066          * Check to schedule QUEUE_FULL work, or execute an existing
2067          * cmd->transport_qf_callback()
2068          */
2069         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2070                 schedule_work(&cmd->se_dev->qf_work_queue);
2071
2072         /*
2073          * Check if we need to send a sense buffer from
2074          * the struct se_cmd in question.
2075          */
2076         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2077                 WARN_ON(!cmd->scsi_status);
2078                 ret = transport_send_check_condition_and_sense(
2079                                         cmd, 0, 1);
2080                 if (ret == -EAGAIN || ret == -ENOMEM)
2081                         goto queue_full;
2082
2083                 transport_lun_remove_cmd(cmd);
2084                 transport_cmd_check_stop_to_fabric(cmd);
2085                 return;
2086         }
2087         /*
2088          * Check for a callback, used by amongst other things
2089          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2090          */
2091         if (cmd->transport_complete_callback) {
2092                 sense_reason_t rc;
2093                 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2094                 bool zero_dl = !(cmd->data_length);
2095                 int post_ret = 0;
2096
2097                 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2098                 if (!rc && !post_ret) {
2099                         if (caw && zero_dl)
2100                                 goto queue_rsp;
2101
2102                         return;
2103                 } else if (rc) {
2104                         ret = transport_send_check_condition_and_sense(cmd,
2105                                                 rc, 0);
2106                         if (ret == -EAGAIN || ret == -ENOMEM)
2107                                 goto queue_full;
2108
2109                         transport_lun_remove_cmd(cmd);
2110                         transport_cmd_check_stop_to_fabric(cmd);
2111                         return;
2112                 }
2113         }
2114
2115 queue_rsp:
2116         switch (cmd->data_direction) {
2117         case DMA_FROM_DEVICE:
2118                 atomic_long_add(cmd->data_length,
2119                                 &cmd->se_lun->lun_stats.tx_data_octets);
2120                 /*
2121                  * Perform READ_STRIP of PI using software emulation when
2122                  * backend had PI enabled, if the transport will not be
2123                  * performing hardware READ_STRIP offload.
2124                  */
2125                 if (target_read_prot_action(cmd)) {
2126                         ret = transport_send_check_condition_and_sense(cmd,
2127                                                 cmd->pi_err, 0);
2128                         if (ret == -EAGAIN || ret == -ENOMEM)
2129                                 goto queue_full;
2130
2131                         transport_lun_remove_cmd(cmd);
2132                         transport_cmd_check_stop_to_fabric(cmd);
2133                         return;
2134                 }
2135
2136                 trace_target_cmd_complete(cmd);
2137                 ret = cmd->se_tfo->queue_data_in(cmd);
2138                 if (ret == -EAGAIN || ret == -ENOMEM)
2139                         goto queue_full;
2140                 break;
2141         case DMA_TO_DEVICE:
2142                 atomic_long_add(cmd->data_length,
2143                                 &cmd->se_lun->lun_stats.rx_data_octets);
2144                 /*
2145                  * Check if we need to send READ payload for BIDI-COMMAND
2146                  */
2147                 if (cmd->se_cmd_flags & SCF_BIDI) {
2148                         atomic_long_add(cmd->data_length,
2149                                         &cmd->se_lun->lun_stats.tx_data_octets);
2150                         ret = cmd->se_tfo->queue_data_in(cmd);
2151                         if (ret == -EAGAIN || ret == -ENOMEM)
2152                                 goto queue_full;
2153                         break;
2154                 }
2155                 /* Fall through for DMA_TO_DEVICE */
2156         case DMA_NONE:
2157                 trace_target_cmd_complete(cmd);
2158                 ret = cmd->se_tfo->queue_status(cmd);
2159                 if (ret == -EAGAIN || ret == -ENOMEM)
2160                         goto queue_full;
2161                 break;
2162         default:
2163                 break;
2164         }
2165
2166         transport_lun_remove_cmd(cmd);
2167         transport_cmd_check_stop_to_fabric(cmd);
2168         return;
2169
2170 queue_full:
2171         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2172                 " data_direction: %d\n", cmd, cmd->data_direction);
2173         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2174         transport_handle_queue_full(cmd, cmd->se_dev);
2175 }
2176
2177 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2178 {
2179         struct scatterlist *sg;
2180         int count;
2181
2182         for_each_sg(sgl, sg, nents, count)
2183                 __free_page(sg_page(sg));
2184
2185         kfree(sgl);
2186 }
2187
2188 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2189 {
2190         /*
2191          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2192          * emulation, and free + reset pointers if necessary..
2193          */
2194         if (!cmd->t_data_sg_orig)
2195                 return;
2196
2197         kfree(cmd->t_data_sg);
2198         cmd->t_data_sg = cmd->t_data_sg_orig;
2199         cmd->t_data_sg_orig = NULL;
2200         cmd->t_data_nents = cmd->t_data_nents_orig;
2201         cmd->t_data_nents_orig = 0;
2202 }
2203
2204 static inline void transport_free_pages(struct se_cmd *cmd)
2205 {
2206         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2207                 transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2208                 cmd->t_prot_sg = NULL;
2209                 cmd->t_prot_nents = 0;
2210         }
2211
2212         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2213                 /*
2214                  * Release special case READ buffer payload required for
2215                  * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2216                  */
2217                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2218                         transport_free_sgl(cmd->t_bidi_data_sg,
2219                                            cmd->t_bidi_data_nents);
2220                         cmd->t_bidi_data_sg = NULL;
2221                         cmd->t_bidi_data_nents = 0;
2222                 }
2223                 transport_reset_sgl_orig(cmd);
2224                 return;
2225         }
2226         transport_reset_sgl_orig(cmd);
2227
2228         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2229         cmd->t_data_sg = NULL;
2230         cmd->t_data_nents = 0;
2231
2232         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2233         cmd->t_bidi_data_sg = NULL;
2234         cmd->t_bidi_data_nents = 0;
2235 }
2236
2237 /**
2238  * transport_put_cmd - release a reference to a command
2239  * @cmd:       command to release
2240  *
2241  * This routine releases our reference to the command and frees it if possible.
2242  */
2243 static int transport_put_cmd(struct se_cmd *cmd)
2244 {
2245         BUG_ON(!cmd->se_tfo);
2246         /*
2247          * If this cmd has been setup with target_get_sess_cmd(), drop
2248          * the kref and call ->release_cmd() in kref callback.
2249          */
2250         return target_put_sess_cmd(cmd);
2251 }
2252
2253 void *transport_kmap_data_sg(struct se_cmd *cmd)
2254 {
2255         struct scatterlist *sg = cmd->t_data_sg;
2256         struct page **pages;
2257         int i;
2258
2259         /*
2260          * We need to take into account a possible offset here for fabrics like
2261          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2262          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2263          */
2264         if (!cmd->t_data_nents)
2265                 return NULL;
2266
2267         BUG_ON(!sg);
2268         if (cmd->t_data_nents == 1)
2269                 return kmap(sg_page(sg)) + sg->offset;
2270
2271         /* >1 page. use vmap */
2272         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2273         if (!pages)
2274                 return NULL;
2275
2276         /* convert sg[] to pages[] */
2277         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2278                 pages[i] = sg_page(sg);
2279         }
2280
2281         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2282         kfree(pages);
2283         if (!cmd->t_data_vmap)
2284                 return NULL;
2285
2286         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2287 }
2288 EXPORT_SYMBOL(transport_kmap_data_sg);
2289
2290 void transport_kunmap_data_sg(struct se_cmd *cmd)
2291 {
2292         if (!cmd->t_data_nents) {
2293                 return;
2294         } else if (cmd->t_data_nents == 1) {
2295                 kunmap(sg_page(cmd->t_data_sg));
2296                 return;
2297         }
2298
2299         vunmap(cmd->t_data_vmap);
2300         cmd->t_data_vmap = NULL;
2301 }
2302 EXPORT_SYMBOL(transport_kunmap_data_sg);
2303
2304 int
2305 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2306                  bool zero_page)
2307 {
2308         struct scatterlist *sg;
2309         struct page *page;
2310         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2311         unsigned int nent;
2312         int i = 0;
2313
2314         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2315         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2316         if (!sg)
2317                 return -ENOMEM;
2318
2319         sg_init_table(sg, nent);
2320
2321         while (length) {
2322                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2323                 page = alloc_page(GFP_KERNEL | zero_flag);
2324                 if (!page)
2325                         goto out;
2326
2327                 sg_set_page(&sg[i], page, page_len, 0);
2328                 length -= page_len;
2329                 i++;
2330         }
2331         *sgl = sg;
2332         *nents = nent;
2333         return 0;
2334
2335 out:
2336         while (i > 0) {
2337                 i--;
2338                 __free_page(sg_page(&sg[i]));
2339         }
2340         kfree(sg);
2341         return -ENOMEM;
2342 }
2343
2344 /*
2345  * Allocate any required resources to execute the command.  For writes we
2346  * might not have the payload yet, so notify the fabric via a call to
2347  * ->write_pending instead. Otherwise place it on the execution queue.
2348  */
2349 sense_reason_t
2350 transport_generic_new_cmd(struct se_cmd *cmd)
2351 {
2352         int ret = 0;
2353         bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2354
2355         if (cmd->prot_op != TARGET_PROT_NORMAL &&
2356             !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2357                 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2358                                        cmd->prot_length, true);
2359                 if (ret < 0)
2360                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2361         }
2362
2363         /*
2364          * Determine is the TCM fabric module has already allocated physical
2365          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2366          * beforehand.
2367          */
2368         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2369             cmd->data_length) {
2370
2371                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2372                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2373                         u32 bidi_length;
2374
2375                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2376                                 bidi_length = cmd->t_task_nolb *
2377                                               cmd->se_dev->dev_attrib.block_size;
2378                         else
2379                                 bidi_length = cmd->data_length;
2380
2381                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2382                                                &cmd->t_bidi_data_nents,
2383                                                bidi_length, zero_flag);
2384                         if (ret < 0)
2385                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2386                 }
2387
2388                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2389                                        cmd->data_length, zero_flag);
2390                 if (ret < 0)
2391                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2392         } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2393                     cmd->data_length) {
2394                 /*
2395                  * Special case for COMPARE_AND_WRITE with fabrics
2396                  * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2397                  */
2398                 u32 caw_length = cmd->t_task_nolb *
2399                                  cmd->se_dev->dev_attrib.block_size;
2400
2401                 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2402                                        &cmd->t_bidi_data_nents,
2403                                        caw_length, zero_flag);
2404                 if (ret < 0)
2405                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2406         }
2407         /*
2408          * If this command is not a write we can execute it right here,
2409          * for write buffers we need to notify the fabric driver first
2410          * and let it call back once the write buffers are ready.
2411          */
2412         target_add_to_state_list(cmd);
2413         if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2414                 target_execute_cmd(cmd);
2415                 return 0;
2416         }
2417         transport_cmd_check_stop(cmd, false, true);
2418
2419         ret = cmd->se_tfo->write_pending(cmd);
2420         if (ret == -EAGAIN || ret == -ENOMEM)
2421                 goto queue_full;
2422
2423         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2424         WARN_ON(ret);
2425
2426         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2427
2428 queue_full:
2429         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2430         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2431         transport_handle_queue_full(cmd, cmd->se_dev);
2432         return 0;
2433 }
2434 EXPORT_SYMBOL(transport_generic_new_cmd);
2435
2436 static void transport_write_pending_qf(struct se_cmd *cmd)
2437 {
2438         int ret;
2439
2440         ret = cmd->se_tfo->write_pending(cmd);
2441         if (ret == -EAGAIN || ret == -ENOMEM) {
2442                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2443                          cmd);
2444                 transport_handle_queue_full(cmd, cmd->se_dev);
2445         }
2446 }
2447
2448 static bool
2449 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2450                            unsigned long *flags);
2451
2452 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2453 {
2454         unsigned long flags;
2455
2456         spin_lock_irqsave(&cmd->t_state_lock, flags);
2457         __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2458         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2459 }
2460
2461 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2462 {
2463         int ret = 0;
2464         bool aborted = false, tas = false;
2465
2466         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2467                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2468                         target_wait_free_cmd(cmd, &aborted, &tas);
2469
2470                 if (!aborted || tas)
2471                         ret = transport_put_cmd(cmd);
2472         } else {
2473                 if (wait_for_tasks)
2474                         target_wait_free_cmd(cmd, &aborted, &tas);
2475                 /*
2476                  * Handle WRITE failure case where transport_generic_new_cmd()
2477                  * has already added se_cmd to state_list, but fabric has
2478                  * failed command before I/O submission.
2479                  */
2480                 if (cmd->state_active)
2481                         target_remove_from_state_list(cmd);
2482
2483                 if (cmd->se_lun)
2484                         transport_lun_remove_cmd(cmd);
2485
2486                 if (!aborted || tas)
2487                         ret = transport_put_cmd(cmd);
2488         }
2489         /*
2490          * If the task has been internally aborted due to TMR ABORT_TASK
2491          * or LUN_RESET, target_core_tmr.c is responsible for performing
2492          * the remaining calls to target_put_sess_cmd(), and not the
2493          * callers of this function.
2494          */
2495         if (aborted) {
2496                 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2497                 wait_for_completion(&cmd->cmd_wait_comp);
2498                 cmd->se_tfo->release_cmd(cmd);
2499                 ret = 1;
2500         }
2501         return ret;
2502 }
2503 EXPORT_SYMBOL(transport_generic_free_cmd);
2504
2505 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2506  * @se_cmd:     command descriptor to add
2507  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2508  */
2509 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2510 {
2511         struct se_session *se_sess = se_cmd->se_sess;
2512         unsigned long flags;
2513         int ret = 0;
2514
2515         /*
2516          * Add a second kref if the fabric caller is expecting to handle
2517          * fabric acknowledgement that requires two target_put_sess_cmd()
2518          * invocations before se_cmd descriptor release.
2519          */
2520         if (ack_kref) {
2521                 kref_get(&se_cmd->cmd_kref);
2522                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2523         }
2524
2525         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2526         if (se_sess->sess_tearing_down) {
2527                 ret = -ESHUTDOWN;
2528                 goto out;
2529         }
2530         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2531 out:
2532         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2533
2534         if (ret && ack_kref)
2535                 target_put_sess_cmd(se_cmd);
2536
2537         return ret;
2538 }
2539 EXPORT_SYMBOL(target_get_sess_cmd);
2540
2541 static void target_free_cmd_mem(struct se_cmd *cmd)
2542 {
2543         transport_free_pages(cmd);
2544
2545         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2546                 core_tmr_release_req(cmd->se_tmr_req);
2547         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2548                 kfree(cmd->t_task_cdb);
2549 }
2550
2551 static void target_release_cmd_kref(struct kref *kref)
2552 {
2553         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2554         struct se_session *se_sess = se_cmd->se_sess;
2555         unsigned long flags;
2556         bool fabric_stop;
2557
2558         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2559
2560         spin_lock(&se_cmd->t_state_lock);
2561         fabric_stop = (se_cmd->transport_state & CMD_T_FABRIC_STOP) &&
2562                       (se_cmd->transport_state & CMD_T_ABORTED);
2563         spin_unlock(&se_cmd->t_state_lock);
2564
2565         if (se_cmd->cmd_wait_set || fabric_stop) {
2566                 list_del_init(&se_cmd->se_cmd_list);
2567                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2568                 target_free_cmd_mem(se_cmd);
2569                 complete(&se_cmd->cmd_wait_comp);
2570                 return;
2571         }
2572         list_del_init(&se_cmd->se_cmd_list);
2573         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2574
2575         target_free_cmd_mem(se_cmd);
2576         se_cmd->se_tfo->release_cmd(se_cmd);
2577 }
2578
2579 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2580  * @se_cmd:     command descriptor to drop
2581  */
2582 int target_put_sess_cmd(struct se_cmd *se_cmd)
2583 {
2584         struct se_session *se_sess = se_cmd->se_sess;
2585
2586         if (!se_sess) {
2587                 target_free_cmd_mem(se_cmd);
2588                 se_cmd->se_tfo->release_cmd(se_cmd);
2589                 return 1;
2590         }
2591         return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2592 }
2593 EXPORT_SYMBOL(target_put_sess_cmd);
2594
2595 /* target_sess_cmd_list_set_waiting - Flag all commands in
2596  *         sess_cmd_list to complete cmd_wait_comp.  Set
2597  *         sess_tearing_down so no more commands are queued.
2598  * @se_sess:    session to flag
2599  */
2600 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2601 {
2602         struct se_cmd *se_cmd;
2603         unsigned long flags;
2604         int rc;
2605
2606         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2607         if (se_sess->sess_tearing_down) {
2608                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2609                 return;
2610         }
2611         se_sess->sess_tearing_down = 1;
2612         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2613
2614         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list) {
2615                 rc = kref_get_unless_zero(&se_cmd->cmd_kref);
2616                 if (rc) {
2617                         se_cmd->cmd_wait_set = 1;
2618                         spin_lock(&se_cmd->t_state_lock);
2619                         se_cmd->transport_state |= CMD_T_FABRIC_STOP;
2620                         spin_unlock(&se_cmd->t_state_lock);
2621                 }
2622         }
2623
2624         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2625 }
2626 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2627
2628 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2629  * @se_sess:    session to wait for active I/O
2630  */
2631 void target_wait_for_sess_cmds(struct se_session *se_sess)
2632 {
2633         struct se_cmd *se_cmd, *tmp_cmd;
2634         unsigned long flags;
2635         bool tas;
2636
2637         list_for_each_entry_safe(se_cmd, tmp_cmd,
2638                                 &se_sess->sess_wait_list, se_cmd_list) {
2639                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2640                         " %d\n", se_cmd, se_cmd->t_state,
2641                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2642
2643                 spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2644                 tas = (se_cmd->transport_state & CMD_T_TAS);
2645                 spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2646
2647                 if (!target_put_sess_cmd(se_cmd)) {
2648                         if (tas)
2649                                 target_put_sess_cmd(se_cmd);
2650                 }
2651
2652                 wait_for_completion(&se_cmd->cmd_wait_comp);
2653                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2654                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2655                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2656
2657                 se_cmd->se_tfo->release_cmd(se_cmd);
2658         }
2659
2660         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2661         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2662         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2663
2664 }
2665 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2666
2667 void transport_clear_lun_ref(struct se_lun *lun)
2668 {
2669         percpu_ref_kill(&lun->lun_ref);
2670         wait_for_completion(&lun->lun_ref_comp);
2671 }
2672
2673 static bool
2674 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2675                            bool *aborted, bool *tas, unsigned long *flags)
2676         __releases(&cmd->t_state_lock)
2677         __acquires(&cmd->t_state_lock)
2678 {
2679
2680         assert_spin_locked(&cmd->t_state_lock);
2681         WARN_ON_ONCE(!irqs_disabled());
2682
2683         if (fabric_stop)
2684                 cmd->transport_state |= CMD_T_FABRIC_STOP;
2685
2686         if (cmd->transport_state & CMD_T_ABORTED)
2687                 *aborted = true;
2688
2689         if (cmd->transport_state & CMD_T_TAS)
2690                 *tas = true;
2691
2692         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2693             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2694                 return false;
2695
2696         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2697             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2698                 return false;
2699
2700         if (!(cmd->transport_state & CMD_T_ACTIVE))
2701                 return false;
2702
2703         if (fabric_stop && *aborted)
2704                 return false;
2705
2706         cmd->transport_state |= CMD_T_STOP;
2707
2708         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08llx i_state: %d,"
2709                  " t_state: %d, CMD_T_STOP\n", cmd, cmd->tag,
2710                  cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2711
2712         spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2713
2714         wait_for_completion(&cmd->t_transport_stop_comp);
2715
2716         spin_lock_irqsave(&cmd->t_state_lock, *flags);
2717         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2718
2719         pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
2720                  "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
2721
2722         return true;
2723 }
2724
2725 /**
2726  * transport_wait_for_tasks - wait for completion to occur
2727  * @cmd:        command to wait
2728  *
2729  * Called from frontend fabric context to wait for storage engine
2730  * to pause and/or release frontend generated struct se_cmd.
2731  */
2732 bool transport_wait_for_tasks(struct se_cmd *cmd)
2733 {
2734         unsigned long flags;
2735         bool ret, aborted = false, tas = false;
2736
2737         spin_lock_irqsave(&cmd->t_state_lock, flags);
2738         ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
2739         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2740
2741         return ret;
2742 }
2743 EXPORT_SYMBOL(transport_wait_for_tasks);
2744
2745 struct sense_info {
2746         u8 key;
2747         u8 asc;
2748         u8 ascq;
2749         bool add_sector_info;
2750 };
2751
2752 static const struct sense_info sense_info_table[] = {
2753         [TCM_NO_SENSE] = {
2754                 .key = NOT_READY
2755         },
2756         [TCM_NON_EXISTENT_LUN] = {
2757                 .key = ILLEGAL_REQUEST,
2758                 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
2759         },
2760         [TCM_UNSUPPORTED_SCSI_OPCODE] = {
2761                 .key = ILLEGAL_REQUEST,
2762                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2763         },
2764         [TCM_SECTOR_COUNT_TOO_MANY] = {
2765                 .key = ILLEGAL_REQUEST,
2766                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2767         },
2768         [TCM_UNKNOWN_MODE_PAGE] = {
2769                 .key = ILLEGAL_REQUEST,
2770                 .asc = 0x24, /* INVALID FIELD IN CDB */
2771         },
2772         [TCM_CHECK_CONDITION_ABORT_CMD] = {
2773                 .key = ABORTED_COMMAND,
2774                 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
2775                 .ascq = 0x03,
2776         },
2777         [TCM_INCORRECT_AMOUNT_OF_DATA] = {
2778                 .key = ABORTED_COMMAND,
2779                 .asc = 0x0c, /* WRITE ERROR */
2780                 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
2781         },
2782         [TCM_INVALID_CDB_FIELD] = {
2783                 .key = ILLEGAL_REQUEST,
2784                 .asc = 0x24, /* INVALID FIELD IN CDB */
2785         },
2786         [TCM_INVALID_PARAMETER_LIST] = {
2787                 .key = ILLEGAL_REQUEST,
2788                 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
2789         },
2790         [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
2791                 .key = ILLEGAL_REQUEST,
2792                 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
2793         },
2794         [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
2795                 .key = ILLEGAL_REQUEST,
2796                 .asc = 0x0c, /* WRITE ERROR */
2797                 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
2798         },
2799         [TCM_SERVICE_CRC_ERROR] = {
2800                 .key = ABORTED_COMMAND,
2801                 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
2802                 .ascq = 0x05, /* N/A */
2803         },
2804         [TCM_SNACK_REJECTED] = {
2805                 .key = ABORTED_COMMAND,
2806                 .asc = 0x11, /* READ ERROR */
2807                 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
2808         },
2809         [TCM_WRITE_PROTECTED] = {
2810                 .key = DATA_PROTECT,
2811                 .asc = 0x27, /* WRITE PROTECTED */
2812         },
2813         [TCM_ADDRESS_OUT_OF_RANGE] = {
2814                 .key = ILLEGAL_REQUEST,
2815                 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2816         },
2817         [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
2818                 .key = UNIT_ATTENTION,
2819         },
2820         [TCM_CHECK_CONDITION_NOT_READY] = {
2821                 .key = NOT_READY,
2822         },
2823         [TCM_MISCOMPARE_VERIFY] = {
2824                 .key = MISCOMPARE,
2825                 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
2826                 .ascq = 0x00,
2827         },
2828         [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
2829                 .key = ABORTED_COMMAND,
2830                 .asc = 0x10,
2831                 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
2832                 .add_sector_info = true,
2833         },
2834         [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
2835                 .key = ABORTED_COMMAND,
2836                 .asc = 0x10,
2837                 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2838                 .add_sector_info = true,
2839         },
2840         [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
2841                 .key = ABORTED_COMMAND,
2842                 .asc = 0x10,
2843                 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2844                 .add_sector_info = true,
2845         },
2846         [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
2847                 .key = COPY_ABORTED,
2848                 .asc = 0x0d,
2849                 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
2850
2851         },
2852         [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
2853                 /*
2854                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2855                  * Solaris initiators.  Returning NOT READY instead means the
2856                  * operations will be retried a finite number of times and we
2857                  * can survive intermittent errors.
2858                  */
2859                 .key = NOT_READY,
2860                 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
2861         },
2862 };
2863
2864 static int translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
2865 {
2866         const struct sense_info *si;
2867         u8 *buffer = cmd->sense_buffer;
2868         int r = (__force int)reason;
2869         u8 asc, ascq;
2870         bool desc_format = target_sense_desc_format(cmd->se_dev);
2871
2872         if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
2873                 si = &sense_info_table[r];
2874         else
2875                 si = &sense_info_table[(__force int)
2876                                        TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
2877
2878         if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
2879                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2880                 WARN_ON_ONCE(asc == 0);
2881         } else if (si->asc == 0) {
2882                 WARN_ON_ONCE(cmd->scsi_asc == 0);
2883                 asc = cmd->scsi_asc;
2884                 ascq = cmd->scsi_ascq;
2885         } else {
2886                 asc = si->asc;
2887                 ascq = si->ascq;
2888         }
2889
2890         scsi_build_sense_buffer(desc_format, buffer, si->key, asc, ascq);
2891         if (si->add_sector_info)
2892                 return scsi_set_sense_information(buffer,
2893                                                   cmd->scsi_sense_length,
2894                                                   cmd->bad_sector);
2895
2896         return 0;
2897 }
2898
2899 int
2900 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2901                 sense_reason_t reason, int from_transport)
2902 {
2903         unsigned long flags;
2904
2905         spin_lock_irqsave(&cmd->t_state_lock, flags);
2906         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2907                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2908                 return 0;
2909         }
2910         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2911         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2912
2913         if (!from_transport) {
2914                 int rc;
2915
2916                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2917                 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2918                 cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2919                 rc = translate_sense_reason(cmd, reason);
2920                 if (rc)
2921                         return rc;
2922         }
2923
2924         trace_target_cmd_complete(cmd);
2925         return cmd->se_tfo->queue_status(cmd);
2926 }
2927 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2928
2929 static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2930         __releases(&cmd->t_state_lock)
2931         __acquires(&cmd->t_state_lock)
2932 {
2933         assert_spin_locked(&cmd->t_state_lock);
2934         WARN_ON_ONCE(!irqs_disabled());
2935
2936         if (!(cmd->transport_state & CMD_T_ABORTED))
2937                 return 0;
2938         /*
2939          * If cmd has been aborted but either no status is to be sent or it has
2940          * already been sent, just return
2941          */
2942         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
2943                 if (send_status)
2944                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2945                 return 1;
2946         }
2947
2948         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
2949                 " 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);
2950
2951         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2952         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2953         trace_target_cmd_complete(cmd);
2954
2955         spin_unlock_irq(&cmd->t_state_lock);
2956         cmd->se_tfo->queue_status(cmd);
2957         spin_lock_irq(&cmd->t_state_lock);
2958
2959         return 1;
2960 }
2961
2962 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2963 {
2964         int ret;
2965
2966         spin_lock_irq(&cmd->t_state_lock);
2967         ret = __transport_check_aborted_status(cmd, send_status);
2968         spin_unlock_irq(&cmd->t_state_lock);
2969
2970         return ret;
2971 }
2972 EXPORT_SYMBOL(transport_check_aborted_status);
2973
2974 void transport_send_task_abort(struct se_cmd *cmd)
2975 {
2976         unsigned long flags;
2977
2978         spin_lock_irqsave(&cmd->t_state_lock, flags);
2979         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2980                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2981                 return;
2982         }
2983         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2984
2985         /*
2986          * If there are still expected incoming fabric WRITEs, we wait
2987          * until until they have completed before sending a TASK_ABORTED
2988          * response.  This response with TASK_ABORTED status will be
2989          * queued back to fabric module by transport_check_aborted_status().
2990          */
2991         if (cmd->data_direction == DMA_TO_DEVICE) {
2992                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2993                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2994                         if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) {
2995                                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2996                                 goto send_abort;
2997                         }
2998                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2999                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3000                         return;
3001                 }
3002         }
3003 send_abort:
3004         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3005
3006         transport_lun_remove_cmd(cmd);
3007
3008         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
3009                  cmd->t_task_cdb[0], cmd->tag);
3010
3011         trace_target_cmd_complete(cmd);
3012         cmd->se_tfo->queue_status(cmd);
3013 }
3014
3015 static void target_tmr_work(struct work_struct *work)
3016 {
3017         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3018         struct se_device *dev = cmd->se_dev;
3019         struct se_tmr_req *tmr = cmd->se_tmr_req;
3020         unsigned long flags;
3021         int ret;
3022
3023         spin_lock_irqsave(&cmd->t_state_lock, flags);
3024         if (cmd->transport_state & CMD_T_ABORTED) {
3025                 tmr->response = TMR_FUNCTION_REJECTED;
3026                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3027                 goto check_stop;
3028         }
3029         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3030
3031         switch (tmr->function) {
3032         case TMR_ABORT_TASK:
3033                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3034                 break;
3035         case TMR_ABORT_TASK_SET:
3036         case TMR_CLEAR_ACA:
3037         case TMR_CLEAR_TASK_SET:
3038                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3039                 break;
3040         case TMR_LUN_RESET:
3041                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3042                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3043                                          TMR_FUNCTION_REJECTED;
3044                 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3045                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3046                                                cmd->orig_fe_lun, 0x29,
3047                                                ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3048                 }
3049                 break;
3050         case TMR_TARGET_WARM_RESET:
3051                 tmr->response = TMR_FUNCTION_REJECTED;
3052                 break;
3053         case TMR_TARGET_COLD_RESET:
3054                 tmr->response = TMR_FUNCTION_REJECTED;
3055                 break;
3056         default:
3057                 pr_err("Uknown TMR function: 0x%02x.\n",
3058                                 tmr->function);
3059                 tmr->response = TMR_FUNCTION_REJECTED;
3060                 break;
3061         }
3062
3063         spin_lock_irqsave(&cmd->t_state_lock, flags);
3064         if (cmd->transport_state & CMD_T_ABORTED) {
3065                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3066                 goto check_stop;
3067         }
3068         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3069
3070         cmd->se_tfo->queue_tm_rsp(cmd);
3071
3072 check_stop:
3073         transport_cmd_check_stop_to_fabric(cmd);
3074 }
3075
3076 int transport_generic_handle_tmr(
3077         struct se_cmd *cmd)
3078 {
3079         unsigned long flags;
3080         bool aborted = false;
3081
3082         spin_lock_irqsave(&cmd->t_state_lock, flags);
3083         if (cmd->transport_state & CMD_T_ABORTED) {
3084                 aborted = true;
3085         } else {
3086                 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3087                 cmd->transport_state |= CMD_T_ACTIVE;
3088         }
3089         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3090
3091         if (aborted) {
3092                 pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d"
3093                         "ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function,
3094                         cmd->se_tmr_req->ref_task_tag, cmd->tag);
3095                 transport_cmd_check_stop_to_fabric(cmd);
3096                 return 0;
3097         }
3098
3099         INIT_WORK(&cmd->work, target_tmr_work);
3100         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3101         return 0;
3102 }
3103 EXPORT_SYMBOL(transport_generic_handle_tmr);
3104
3105 bool
3106 target_check_wce(struct se_device *dev)
3107 {
3108         bool wce = false;
3109
3110         if (dev->transport->get_write_cache)
3111                 wce = dev->transport->get_write_cache(dev);
3112         else if (dev->dev_attrib.emulate_write_cache > 0)
3113                 wce = true;
3114
3115         return wce;
3116 }
3117
3118 bool
3119 target_check_fua(struct se_device *dev)
3120 {
3121         return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3122 }