drivers/target/target_core_transport.c

   1 /*******************************************************************************
   2  * Filename:  target_core_transport.c
   3  *
   4  * This file contains the Generic Target Engine Core.
   5  *
   6  * (c) Copyright 2002-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/net.h>
  27 #include <linux/delay.h>
  28 #include <linux/string.h>
  29 #include <linux/timer.h>
  30 #include <linux/slab.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/kthread.h>
  33 #include <linux/in.h>
  34 #include <linux/cdrom.h>
  35 #include <linux/module.h>
  36 #include <linux/ratelimit.h>
  37 #include <asm/unaligned.h>
  38 #include <net/sock.h>
  39 #include <net/tcp.h>
  40 #include <scsi/scsi.h>
  41 #include <scsi/scsi_cmnd.h>
  42 #include <scsi/scsi_tcq.h>
  43
  44 #include <target/target_core_base.h>
  45 #include <target/target_core_backend.h>
  46 #include <target/target_core_fabric.h>
  47
  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                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 269                         vfree(se_sess->sess_cmd_map);
 270                 else
 271                         kfree(se_sess->sess_cmd_map);
 272                 se_sess->sess_cmd_map = NULL;
 273                 return -ENOMEM;
 274         }
 275
 276         return 0;
 277 }
 278 EXPORT_SYMBOL(transport_alloc_session_tags);
 279
 280 struct se_session *transport_init_session_tags(unsigned int tag_num,
 281                                                unsigned int tag_size,
 282                                                enum target_prot_op sup_prot_ops)
 283 {
 284         struct se_session *se_sess;
 285         int rc;
 286
 287         se_sess = transport_init_session(sup_prot_ops);
 288         if (IS_ERR(se_sess))
 289                 return se_sess;
 290
 291         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 292         if (rc < 0) {
 293                 transport_free_session(se_sess);
 294                 return ERR_PTR(-ENOMEM);
 295         }
 296
 297         return se_sess;
 298 }
 299 EXPORT_SYMBOL(transport_init_session_tags);
 300
 301 /*
 302  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 303  */
 304 void __transport_register_session(
 305         struct se_portal_group *se_tpg,
 306         struct se_node_acl *se_nacl,
 307         struct se_session *se_sess,
 308         void *fabric_sess_ptr)
 309 {
 310         const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
 311         unsigned char buf[PR_REG_ISID_LEN];
 312
 313         se_sess->se_tpg = se_tpg;
 314         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 315         /*
 316          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 317          *
 318          * Only set for struct se_session's that will actually be moving I/O.
 319          * eg: *NOT* discovery sessions.
 320          */
 321         if (se_nacl) {
 322                 /*
 323                  *
 324                  * Determine if fabric allows for T10-PI feature bits exposed to
 325                  * initiators for device backends with !dev->dev_attrib.pi_prot_type.
 326                  *
 327                  * If so, then always save prot_type on a per se_node_acl node
 328                  * basis and re-instate the previous sess_prot_type to avoid
 329                  * disabling PI from below any previously initiator side
 330                  * registered LUNs.
 331                  */
 332                 if (se_nacl->saved_prot_type)
 333                         se_sess->sess_prot_type = se_nacl->saved_prot_type;
 334                 else if (tfo->tpg_check_prot_fabric_only)
 335                         se_sess->sess_prot_type = se_nacl->saved_prot_type =
 336                                         tfo->tpg_check_prot_fabric_only(se_tpg);
 337                 /*
 338                  * If the fabric module supports an ISID based TransportID,
 339                  * save this value in binary from the fabric I_T Nexus now.
 340                  */
 341                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 342                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 343                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 344                                         &buf[0], PR_REG_ISID_LEN);
 345                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 346                 }
 347                 kref_get(&se_nacl->acl_kref);
 348
 349                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 350                 /*
 351                  * The se_nacl->nacl_sess pointer will be set to the
 352                  * last active I_T Nexus for each struct se_node_acl.
 353                  */
 354                 se_nacl->nacl_sess = se_sess;
 355
 356                 list_add_tail(&se_sess->sess_acl_list,
 357                               &se_nacl->acl_sess_list);
 358                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 359         }
 360         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 361
 362         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 363                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 364 }
 365 EXPORT_SYMBOL(__transport_register_session);
 366
 367 void transport_register_session(
 368         struct se_portal_group *se_tpg,
 369         struct se_node_acl *se_nacl,
 370         struct se_session *se_sess,
 371         void *fabric_sess_ptr)
 372 {
 373         unsigned long flags;
 374
 375         spin_lock_irqsave(&se_tpg->session_lock, flags);
 376         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 377         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 378 }
 379 EXPORT_SYMBOL(transport_register_session);
 380
 381 static void target_release_session(struct kref *kref)
 382 {
 383         struct se_session *se_sess = container_of(kref,
 384                         struct se_session, sess_kref);
 385         struct se_portal_group *se_tpg = se_sess->se_tpg;
 386
 387         se_tpg->se_tpg_tfo->close_session(se_sess);
 388 }
 389
 390 void target_get_session(struct se_session *se_sess)
 391 {
 392         kref_get(&se_sess->sess_kref);
 393 }
 394 EXPORT_SYMBOL(target_get_session);
 395
 396 void target_put_session(struct se_session *se_sess)
 397 {
 398         kref_put(&se_sess->sess_kref, target_release_session);
 399 }
 400 EXPORT_SYMBOL(target_put_session);
 401
 402 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
 403 {
 404         struct se_session *se_sess;
 405         ssize_t len = 0;
 406
 407         spin_lock_bh(&se_tpg->session_lock);
 408         list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
 409                 if (!se_sess->se_node_acl)
 410                         continue;
 411                 if (!se_sess->se_node_acl->dynamic_node_acl)
 412                         continue;
 413                 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
 414                         break;
 415
 416                 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
 417                                 se_sess->se_node_acl->initiatorname);
 418                 len += 1; /* Include NULL terminator */
 419         }
 420         spin_unlock_bh(&se_tpg->session_lock);
 421
 422         return len;
 423 }
 424 EXPORT_SYMBOL(target_show_dynamic_sessions);
 425
 426 static void target_complete_nacl(struct kref *kref)
 427 {
 428         struct se_node_acl *nacl = container_of(kref,
 429                                 struct se_node_acl, acl_kref);
 430
 431         complete(&nacl->acl_free_comp);
 432 }
 433
 434 void target_put_nacl(struct se_node_acl *nacl)
 435 {
 436         kref_put(&nacl->acl_kref, target_complete_nacl);
 437 }
 438
 439 void transport_deregister_session_configfs(struct se_session *se_sess)
 440 {
 441         struct se_node_acl *se_nacl;
 442         unsigned long flags;
 443         /*
 444          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 445          */
 446         se_nacl = se_sess->se_node_acl;
 447         if (se_nacl) {
 448                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 449                 if (se_nacl->acl_stop == 0)
 450                         list_del(&se_sess->sess_acl_list);
 451                 /*
 452                  * If the session list is empty, then clear the pointer.
 453                  * Otherwise, set the struct se_session pointer from the tail
 454                  * element of the per struct se_node_acl active session list.
 455                  */
 456                 if (list_empty(&se_nacl->acl_sess_list))
 457                         se_nacl->nacl_sess = NULL;
 458                 else {
 459                         se_nacl->nacl_sess = container_of(
 460                                         se_nacl->acl_sess_list.prev,
 461                                         struct se_session, sess_acl_list);
 462                 }
 463                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 464         }
 465 }
 466 EXPORT_SYMBOL(transport_deregister_session_configfs);
 467
 468 void transport_free_session(struct se_session *se_sess)
 469 {
 470         if (se_sess->sess_cmd_map) {
 471                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 472                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 473                         vfree(se_sess->sess_cmd_map);
 474                 else
 475                         kfree(se_sess->sess_cmd_map);
 476         }
 477         kmem_cache_free(se_sess_cache, se_sess);
 478 }
 479 EXPORT_SYMBOL(transport_free_session);
 480
 481 void transport_deregister_session(struct se_session *se_sess)
 482 {
 483         struct se_portal_group *se_tpg = se_sess->se_tpg;
 484         const struct target_core_fabric_ops *se_tfo;
 485         struct se_node_acl *se_nacl;
 486         unsigned long flags;
 487         bool comp_nacl = true, drop_nacl = false;
 488
 489         if (!se_tpg) {
 490                 transport_free_session(se_sess);
 491                 return;
 492         }
 493         se_tfo = se_tpg->se_tpg_tfo;
 494
 495         spin_lock_irqsave(&se_tpg->session_lock, flags);
 496         list_del(&se_sess->sess_list);
 497         se_sess->se_tpg = NULL;
 498         se_sess->fabric_sess_ptr = NULL;
 499         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 500
 501         /*
 502          * Determine if we need to do extra work for this initiator node's
 503          * struct se_node_acl if it had been previously dynamically generated.
 504          */
 505         se_nacl = se_sess->se_node_acl;
 506
 507         mutex_lock(&se_tpg->acl_node_mutex);
 508         if (se_nacl && se_nacl->dynamic_node_acl) {
 509                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 510                         list_del(&se_nacl->acl_list);
 511                         se_tpg->num_node_acls--;
 512                         drop_nacl = true;
 513                 }
 514         }
 515         mutex_unlock(&se_tpg->acl_node_mutex);
 516
 517         if (drop_nacl) {
 518                 core_tpg_wait_for_nacl_pr_ref(se_nacl);
 519                 core_free_device_list_for_node(se_nacl, se_tpg);
 520                 kfree(se_nacl);
 521                 comp_nacl = false;
 522         }
 523         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 524                 se_tpg->se_tpg_tfo->get_fabric_name());
 525         /*
 526          * If last kref is dropping now for an explicit NodeACL, awake sleeping
 527          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 528          * removal context.
 529          */
 530         if (se_nacl && comp_nacl)
 531                 target_put_nacl(se_nacl);
 532
 533         transport_free_session(se_sess);
 534 }
 535 EXPORT_SYMBOL(transport_deregister_session);
 536
 537 /*
 538  * Called with cmd->t_state_lock held.
 539  */
 540 static void target_remove_from_state_list(struct se_cmd *cmd)
 541 {
 542         struct se_device *dev = cmd->se_dev;
 543         unsigned long flags;
 544
 545         if (!dev)
 546                 return;
 547
 548         if (cmd->transport_state & CMD_T_BUSY)
 549                 return;
 550
 551         spin_lock_irqsave(&dev->execute_task_lock, flags);
 552         if (cmd->state_active) {
 553                 list_del(&cmd->state_list);
 554                 cmd->state_active = false;
 555         }
 556         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 557 }
 558
 559 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 560                                     bool write_pending)
 561 {
 562         unsigned long flags;
 563
 564         spin_lock_irqsave(&cmd->t_state_lock, flags);
 565         if (write_pending)
 566                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 567
 568         if (remove_from_lists) {
 569                 target_remove_from_state_list(cmd);
 570
 571                 /*
 572                  * Clear struct se_cmd->se_lun before the handoff to FE.
 573                  */
 574                 cmd->se_lun = NULL;
 575         }
 576
 577         /*
 578          * Determine if frontend context caller is requesting the stopping of
 579          * this command for frontend exceptions.
 580          */
 581         if (cmd->transport_state & CMD_T_STOP) {
 582                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
 583                         __func__, __LINE__, cmd->tag);
 584
 585                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 586
 587                 complete_all(&cmd->t_transport_stop_comp);
 588                 return 1;
 589         }
 590
 591         cmd->transport_state &= ~CMD_T_ACTIVE;
 592         if (remove_from_lists) {
 593                 /*
 594                  * Some fabric modules like tcm_loop can release
 595                  * their internally allocated I/O reference now and
 596                  * struct se_cmd now.
 597                  *
 598                  * Fabric modules are expected to return '1' here if the
 599                  * se_cmd being passed is released at this point,
 600                  * or zero if not being released.
 601                  */
 602                 if (cmd->se_tfo->check_stop_free != NULL) {
 603                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 604                         return cmd->se_tfo->check_stop_free(cmd);
 605                 }
 606         }
 607
 608         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 609         return 0;
 610 }
 611
 612 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 613 {
 614         return transport_cmd_check_stop(cmd, true, false);
 615 }
 616
 617 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 618 {
 619         struct se_lun *lun = cmd->se_lun;
 620
 621         if (!lun)
 622                 return;
 623
 624         if (cmpxchg(&cmd->lun_ref_active, true, false))
 625                 percpu_ref_put(&lun->lun_ref);
 626 }
 627
 628 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 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)
 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 sense_reason_t
1085 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1086 {
1087         struct se_device *dev = cmd->se_dev;
1088
1089         if (cmd->unknown_data_length) {
1090                 cmd->data_length = size;
1091         } else if (size != cmd->data_length) {
1092                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1093                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1094                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1095                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1096
1097                 if (cmd->data_direction == DMA_TO_DEVICE) {
1098                         pr_err("Rejecting underflow/overflow"
1099                                         " WRITE data\n");
1100                         return TCM_INVALID_CDB_FIELD;
1101                 }
1102                 /*
1103                  * Reject READ_* or WRITE_* with overflow/underflow for
1104                  * type SCF_SCSI_DATA_CDB.
1105                  */
1106                 if (dev->dev_attrib.block_size != 512)  {
1107                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1108                                 " CDB on non 512-byte sector setup subsystem"
1109                                 " plugin: %s\n", dev->transport->name);
1110                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1111                         return TCM_INVALID_CDB_FIELD;
1112                 }
1113                 /*
1114                  * For the overflow case keep the existing fabric provided
1115                  * ->data_length.  Otherwise for the underflow case, reset
1116                  * ->data_length to the smaller SCSI expected data transfer
1117                  * length.
1118                  */
1119                 if (size > cmd->data_length) {
1120                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1121                         cmd->residual_count = (size - cmd->data_length);
1122                 } else {
1123                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1124                         cmd->residual_count = (cmd->data_length - size);
1125                         cmd->data_length = size;
1126                 }
1127         }
1128
1129         return 0;
1130
1131 }
1132
1133 /*
1134  * Used by fabric modules containing a local struct se_cmd within their
1135  * fabric dependent per I/O descriptor.
1136  *
1137  * Preserves the value of @cmd->tag.
1138  */
1139 void transport_init_se_cmd(
1140         struct se_cmd *cmd,
1141         const struct target_core_fabric_ops *tfo,
1142         struct se_session *se_sess,
1143         u32 data_length,
1144         int data_direction,
1145         int task_attr,
1146         unsigned char *sense_buffer)
1147 {
1148         INIT_LIST_HEAD(&cmd->se_delayed_node);
1149         INIT_LIST_HEAD(&cmd->se_qf_node);
1150         INIT_LIST_HEAD(&cmd->se_cmd_list);
1151         INIT_LIST_HEAD(&cmd->state_list);
1152         init_completion(&cmd->t_transport_stop_comp);
1153         init_completion(&cmd->cmd_wait_comp);
1154         init_completion(&cmd->task_stop_comp);
1155         spin_lock_init(&cmd->t_state_lock);
1156         kref_init(&cmd->cmd_kref);
1157         cmd->transport_state = CMD_T_DEV_ACTIVE;
1158
1159         cmd->se_tfo = tfo;
1160         cmd->se_sess = se_sess;
1161         cmd->data_length = data_length;
1162         cmd->data_direction = data_direction;
1163         cmd->sam_task_attr = task_attr;
1164         cmd->sense_buffer = sense_buffer;
1165
1166         cmd->state_active = false;
1167 }
1168 EXPORT_SYMBOL(transport_init_se_cmd);
1169
1170 static sense_reason_t
1171 transport_check_alloc_task_attr(struct se_cmd *cmd)
1172 {
1173         struct se_device *dev = cmd->se_dev;
1174
1175         /*
1176          * Check if SAM Task Attribute emulation is enabled for this
1177          * struct se_device storage object
1178          */
1179         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1180                 return 0;
1181
1182         if (cmd->sam_task_attr == TCM_ACA_TAG) {
1183                 pr_debug("SAM Task Attribute ACA"
1184                         " emulation is not supported\n");
1185                 return TCM_INVALID_CDB_FIELD;
1186         }
1187         /*
1188          * Used to determine when ORDERED commands should go from
1189          * Dormant to Active status.
1190          */
1191         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1192         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1193                         cmd->se_ordered_id, cmd->sam_task_attr,
1194                         dev->transport->name);
1195         return 0;
1196 }
1197
1198 sense_reason_t
1199 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1200 {
1201         struct se_device *dev = cmd->se_dev;
1202         sense_reason_t ret;
1203
1204         /*
1205          * Ensure that the received CDB is less than the max (252 + 8) bytes
1206          * for VARIABLE_LENGTH_CMD
1207          */
1208         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1209                 pr_err("Received SCSI CDB with command_size: %d that"
1210                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1211                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1212                 return TCM_INVALID_CDB_FIELD;
1213         }
1214         /*
1215          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1216          * allocate the additional extended CDB buffer now..  Otherwise
1217          * setup the pointer from __t_task_cdb to t_task_cdb.
1218          */
1219         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1220                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1221                                                 GFP_KERNEL);
1222                 if (!cmd->t_task_cdb) {
1223                         pr_err("Unable to allocate cmd->t_task_cdb"
1224                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1225                                 scsi_command_size(cdb),
1226                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1227                         return TCM_OUT_OF_RESOURCES;
1228                 }
1229         } else
1230                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1231         /*
1232          * Copy the original CDB into cmd->
1233          */
1234         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1235
1236         trace_target_sequencer_start(cmd);
1237
1238         /*
1239          * Check for an existing UNIT ATTENTION condition
1240          */
1241         ret = target_scsi3_ua_check(cmd);
1242         if (ret)
1243                 return ret;
1244
1245         ret = target_alua_state_check(cmd);
1246         if (ret)
1247                 return ret;
1248
1249         ret = target_check_reservation(cmd);
1250         if (ret) {
1251                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1252                 return ret;
1253         }
1254
1255         ret = dev->transport->parse_cdb(cmd);
1256         if (ret)
1257                 return ret;
1258
1259         ret = transport_check_alloc_task_attr(cmd);
1260         if (ret)
1261                 return ret;
1262
1263         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1264         atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1265         return 0;
1266 }
1267 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1268
1269 /*
1270  * Used by fabric module frontends to queue tasks directly.
1271  * Many only be used from process context only
1272  */
1273 int transport_handle_cdb_direct(
1274         struct se_cmd *cmd)
1275 {
1276         sense_reason_t ret;
1277
1278         if (!cmd->se_lun) {
1279                 dump_stack();
1280                 pr_err("cmd->se_lun is NULL\n");
1281                 return -EINVAL;
1282         }
1283         if (in_interrupt()) {
1284                 dump_stack();
1285                 pr_err("transport_generic_handle_cdb cannot be called"
1286                                 " from interrupt context\n");
1287                 return -EINVAL;
1288         }
1289         /*
1290          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1291          * outstanding descriptors are handled correctly during shutdown via
1292          * transport_wait_for_tasks()
1293          *
1294          * Also, we don't take cmd->t_state_lock here as we only expect
1295          * this to be called for initial descriptor submission.
1296          */
1297         cmd->t_state = TRANSPORT_NEW_CMD;
1298         cmd->transport_state |= CMD_T_ACTIVE;
1299
1300         /*
1301          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1302          * so follow TRANSPORT_NEW_CMD processing thread context usage
1303          * and call transport_generic_request_failure() if necessary..
1304          */
1305         ret = transport_generic_new_cmd(cmd);
1306         if (ret)
1307                 transport_generic_request_failure(cmd, ret);
1308         return 0;
1309 }
1310 EXPORT_SYMBOL(transport_handle_cdb_direct);
1311
1312 sense_reason_t
1313 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1314                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1315 {
1316         if (!sgl || !sgl_count)
1317                 return 0;
1318
1319         /*
1320          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1321          * scatterlists already have been set to follow what the fabric
1322          * passes for the original expected data transfer length.
1323          */
1324         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1325                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1326                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1327                 return TCM_INVALID_CDB_FIELD;
1328         }
1329
1330         cmd->t_data_sg = sgl;
1331         cmd->t_data_nents = sgl_count;
1332         cmd->t_bidi_data_sg = sgl_bidi;
1333         cmd->t_bidi_data_nents = sgl_bidi_count;
1334
1335         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1336         return 0;
1337 }
1338
1339 /*
1340  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1341  *                       se_cmd + use pre-allocated SGL memory.
1342  *
1343  * @se_cmd: command descriptor to submit
1344  * @se_sess: associated se_sess for endpoint
1345  * @cdb: pointer to SCSI CDB
1346  * @sense: pointer to SCSI sense buffer
1347  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1348  * @data_length: fabric expected data transfer length
1349  * @task_addr: SAM task attribute
1350  * @data_dir: DMA data direction
1351  * @flags: flags for command submission from target_sc_flags_tables
1352  * @sgl: struct scatterlist memory for unidirectional mapping
1353  * @sgl_count: scatterlist count for unidirectional mapping
1354  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1355  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1356  * @sgl_prot: struct scatterlist memory protection information
1357  * @sgl_prot_count: scatterlist count for protection information
1358  *
1359  * Task tags are supported if the caller has set @se_cmd->tag.
1360  *
1361  * Returns non zero to signal active I/O shutdown failure.  All other
1362  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1363  * but still return zero here.
1364  *
1365  * This may only be called from process context, and also currently
1366  * assumes internal allocation of fabric payload buffer by target-core.
1367  */
1368 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1369                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1370                 u32 data_length, int task_attr, int data_dir, int flags,
1371                 struct scatterlist *sgl, u32 sgl_count,
1372                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1373                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1374 {
1375         struct se_portal_group *se_tpg;
1376         sense_reason_t rc;
1377         int ret;
1378
1379         se_tpg = se_sess->se_tpg;
1380         BUG_ON(!se_tpg);
1381         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1382         BUG_ON(in_interrupt());
1383         /*
1384          * Initialize se_cmd for target operation.  From this point
1385          * exceptions are handled by sending exception status via
1386          * target_core_fabric_ops->queue_status() callback
1387          */
1388         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1389                                 data_length, data_dir, task_attr, sense);
1390         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1391                 se_cmd->unknown_data_length = 1;
1392         /*
1393          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1394          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1395          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1396          * kref_put() to happen during fabric packet acknowledgement.
1397          */
1398         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1399         if (ret)
1400                 return ret;
1401         /*
1402          * Signal bidirectional data payloads to target-core
1403          */
1404         if (flags & TARGET_SCF_BIDI_OP)
1405                 se_cmd->se_cmd_flags |= SCF_BIDI;
1406         /*
1407          * Locate se_lun pointer and attach it to struct se_cmd
1408          */
1409         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1410         if (rc) {
1411                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1412                 target_put_sess_cmd(se_cmd);
1413                 return 0;
1414         }
1415
1416         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1417         if (rc != 0) {
1418                 transport_generic_request_failure(se_cmd, rc);
1419                 return 0;
1420         }
1421
1422         /*
1423          * Save pointers for SGLs containing protection information,
1424          * if present.
1425          */
1426         if (sgl_prot_count) {
1427                 se_cmd->t_prot_sg = sgl_prot;
1428                 se_cmd->t_prot_nents = sgl_prot_count;
1429                 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1430         }
1431
1432         /*
1433          * When a non zero sgl_count has been passed perform SGL passthrough
1434          * mapping for pre-allocated fabric memory instead of having target
1435          * core perform an internal SGL allocation..
1436          */
1437         if (sgl_count != 0) {
1438                 BUG_ON(!sgl);
1439
1440                 /*
1441                  * A work-around for tcm_loop as some userspace code via
1442                  * scsi-generic do not memset their associated read buffers,
1443                  * so go ahead and do that here for type non-data CDBs.  Also
1444                  * note that this is currently guaranteed to be a single SGL
1445                  * for this case by target core in target_setup_cmd_from_cdb()
1446                  * -> transport_generic_cmd_sequencer().
1447                  */
1448                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1449                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1450                         unsigned char *buf = NULL;
1451
1452                         if (sgl)
1453                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1454
1455                         if (buf) {
1456                                 memset(buf, 0, sgl->length);
1457                                 kunmap(sg_page(sgl));
1458                         }
1459                 }
1460
1461                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1462                                 sgl_bidi, sgl_bidi_count);
1463                 if (rc != 0) {
1464                         transport_generic_request_failure(se_cmd, rc);
1465                         return 0;
1466                 }
1467         }
1468
1469         /*
1470          * Check if we need to delay processing because of ALUA
1471          * Active/NonOptimized primary access state..
1472          */
1473         core_alua_check_nonop_delay(se_cmd);
1474
1475         transport_handle_cdb_direct(se_cmd);
1476         return 0;
1477 }
1478 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1479
1480 /*
1481  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1482  *
1483  * @se_cmd: command descriptor to submit
1484  * @se_sess: associated se_sess for endpoint
1485  * @cdb: pointer to SCSI CDB
1486  * @sense: pointer to SCSI sense buffer
1487  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1488  * @data_length: fabric expected data transfer length
1489  * @task_addr: SAM task attribute
1490  * @data_dir: DMA data direction
1491  * @flags: flags for command submission from target_sc_flags_tables
1492  *
1493  * Task tags are supported if the caller has set @se_cmd->tag.
1494  *
1495  * Returns non zero to signal active I/O shutdown failure.  All other
1496  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1497  * but still return zero here.
1498  *
1499  * This may only be called from process context, and also currently
1500  * assumes internal allocation of fabric payload buffer by target-core.
1501  *
1502  * It also assumes interal target core SGL memory allocation.
1503  */
1504 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1505                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1506                 u32 data_length, int task_attr, int data_dir, int flags)
1507 {
1508         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1509                         unpacked_lun, data_length, task_attr, data_dir,
1510                         flags, NULL, 0, NULL, 0, NULL, 0);
1511 }
1512 EXPORT_SYMBOL(target_submit_cmd);
1513
1514 static void target_complete_tmr_failure(struct work_struct *work)
1515 {
1516         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1517
1518         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1519         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1520
1521         transport_cmd_check_stop_to_fabric(se_cmd);
1522 }
1523
1524 /**
1525  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1526  *                     for TMR CDBs
1527  *
1528  * @se_cmd: command descriptor to submit
1529  * @se_sess: associated se_sess for endpoint
1530  * @sense: pointer to SCSI sense buffer
1531  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1532  * @fabric_context: fabric context for TMR req
1533  * @tm_type: Type of TM request
1534  * @gfp: gfp type for caller
1535  * @tag: referenced task tag for TMR_ABORT_TASK
1536  * @flags: submit cmd flags
1537  *
1538  * Callable from all contexts.
1539  **/
1540
1541 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1542                 unsigned char *sense, u64 unpacked_lun,
1543                 void *fabric_tmr_ptr, unsigned char tm_type,
1544                 gfp_t gfp, unsigned int tag, int flags)
1545 {
1546         struct se_portal_group *se_tpg;
1547         int ret;
1548
1549         se_tpg = se_sess->se_tpg;
1550         BUG_ON(!se_tpg);
1551
1552         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1553                               0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1554         /*
1555          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1556          * allocation failure.
1557          */
1558         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1559         if (ret < 0)
1560                 return -ENOMEM;
1561
1562         if (tm_type == TMR_ABORT_TASK)
1563                 se_cmd->se_tmr_req->ref_task_tag = tag;
1564
1565         /* See target_submit_cmd for commentary */
1566         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1567         if (ret) {
1568                 core_tmr_release_req(se_cmd->se_tmr_req);
1569                 return ret;
1570         }
1571
1572         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1573         if (ret) {
1574                 /*
1575                  * For callback during failure handling, push this work off
1576                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1577                  */
1578                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1579                 schedule_work(&se_cmd->work);
1580                 return 0;
1581         }
1582         transport_generic_handle_tmr(se_cmd);
1583         return 0;
1584 }
1585 EXPORT_SYMBOL(target_submit_tmr);
1586
1587 /*
1588  * If the cmd is active, request it to be stopped and sleep until it
1589  * has completed.
1590  */
1591 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1592         __releases(&cmd->t_state_lock)
1593         __acquires(&cmd->t_state_lock)
1594 {
1595         bool was_active = false;
1596
1597         if (cmd->transport_state & CMD_T_BUSY) {
1598                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1599                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1600
1601                 pr_debug("cmd %p waiting to complete\n", cmd);
1602                 wait_for_completion(&cmd->task_stop_comp);
1603                 pr_debug("cmd %p stopped successfully\n", cmd);
1604
1605                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1606                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1607                 cmd->transport_state &= ~CMD_T_BUSY;
1608                 was_active = true;
1609         }
1610
1611         return was_active;
1612 }
1613
1614 /*
1615  * Handle SAM-esque emulation for generic transport request failures.
1616  */
1617 void transport_generic_request_failure(struct se_cmd *cmd,
1618                 sense_reason_t sense_reason)
1619 {
1620         int ret = 0;
1621
1622         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08llx"
1623                 " CDB: 0x%02x\n", cmd, cmd->tag, cmd->t_task_cdb[0]);
1624         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1625                 cmd->se_tfo->get_cmd_state(cmd),
1626                 cmd->t_state, sense_reason);
1627         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1628                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1629                 (cmd->transport_state & CMD_T_STOP) != 0,
1630                 (cmd->transport_state & CMD_T_SENT) != 0);
1631
1632         /*
1633          * For SAM Task Attribute emulation for failed struct se_cmd
1634          */
1635         transport_complete_task_attr(cmd);
1636         /*
1637          * Handle special case for COMPARE_AND_WRITE failure, where the
1638          * callback is expected to drop the per device ->caw_sem.
1639          */
1640         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1641              cmd->transport_complete_callback)
1642                 cmd->transport_complete_callback(cmd, false);
1643
1644         switch (sense_reason) {
1645         case TCM_NON_EXISTENT_LUN:
1646         case TCM_UNSUPPORTED_SCSI_OPCODE:
1647         case TCM_INVALID_CDB_FIELD:
1648         case TCM_INVALID_PARAMETER_LIST:
1649         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1650         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1651         case TCM_UNKNOWN_MODE_PAGE:
1652         case TCM_WRITE_PROTECTED:
1653         case TCM_ADDRESS_OUT_OF_RANGE:
1654         case TCM_CHECK_CONDITION_ABORT_CMD:
1655         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1656         case TCM_CHECK_CONDITION_NOT_READY:
1657         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1658         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1659         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1660                 break;
1661         case TCM_OUT_OF_RESOURCES:
1662                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1663                 break;
1664         case TCM_RESERVATION_CONFLICT:
1665                 /*
1666                  * No SENSE Data payload for this case, set SCSI Status
1667                  * and queue the response to $FABRIC_MOD.
1668                  *
1669                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1670                  */
1671                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1672                 /*
1673                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1674                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1675                  * CONFLICT STATUS.
1676                  *
1677                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1678                  */
1679                 if (cmd->se_sess &&
1680                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1681                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1682                                 cmd->orig_fe_lun, 0x2C,
1683                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1684
1685                 trace_target_cmd_complete(cmd);
1686                 ret = cmd->se_tfo-> queue_status(cmd);
1687                 if (ret == -EAGAIN || ret == -ENOMEM)
1688                         goto queue_full;
1689                 goto check_stop;
1690         default:
1691                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1692                         cmd->t_task_cdb[0], sense_reason);
1693                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1694                 break;
1695         }
1696
1697         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1698         if (ret == -EAGAIN || ret == -ENOMEM)
1699                 goto queue_full;
1700
1701 check_stop:
1702         transport_lun_remove_cmd(cmd);
1703         if (!transport_cmd_check_stop_to_fabric(cmd))
1704                 ;
1705         return;
1706
1707 queue_full:
1708         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1709         transport_handle_queue_full(cmd, cmd->se_dev);
1710 }
1711 EXPORT_SYMBOL(transport_generic_request_failure);
1712
1713 void __target_execute_cmd(struct se_cmd *cmd)
1714 {
1715         sense_reason_t ret;
1716
1717         if (cmd->execute_cmd) {
1718                 ret = cmd->execute_cmd(cmd);
1719                 if (ret) {
1720                         spin_lock_irq(&cmd->t_state_lock);
1721                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1722                         spin_unlock_irq(&cmd->t_state_lock);
1723
1724                         transport_generic_request_failure(cmd, ret);
1725                 }
1726         }
1727 }
1728
1729 static int target_write_prot_action(struct se_cmd *cmd)
1730 {
1731         u32 sectors;
1732         /*
1733          * Perform WRITE_INSERT of PI using software emulation when backend
1734          * device has PI enabled, if the transport has not already generated
1735          * PI using hardware WRITE_INSERT offload.
1736          */
1737         switch (cmd->prot_op) {
1738         case TARGET_PROT_DOUT_INSERT:
1739                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1740                         sbc_dif_generate(cmd);
1741                 break;
1742         case TARGET_PROT_DOUT_STRIP:
1743                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1744                         break;
1745
1746                 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1747                 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1748                                              sectors, 0, cmd->t_prot_sg, 0);
1749                 if (unlikely(cmd->pi_err)) {
1750                         spin_lock_irq(&cmd->t_state_lock);
1751                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1752                         spin_unlock_irq(&cmd->t_state_lock);
1753                         transport_generic_request_failure(cmd, cmd->pi_err);
1754                         return -1;
1755                 }
1756                 break;
1757         default:
1758                 break;
1759         }
1760
1761         return 0;
1762 }
1763
1764 static bool target_handle_task_attr(struct se_cmd *cmd)
1765 {
1766         struct se_device *dev = cmd->se_dev;
1767
1768         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1769                 return false;
1770
1771         /*
1772          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1773          * to allow the passed struct se_cmd list of tasks to the front of the list.
1774          */
1775         switch (cmd->sam_task_attr) {
1776         case TCM_HEAD_TAG:
1777                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1778                          "se_ordered_id: %u\n",
1779                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1780                 return false;
1781         case TCM_ORDERED_TAG:
1782                 atomic_inc_mb(&dev->dev_ordered_sync);
1783
1784                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1785                          " se_ordered_id: %u\n",
1786                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1787
1788                 /*
1789                  * Execute an ORDERED command if no other older commands
1790                  * exist that need to be completed first.
1791                  */
1792                 if (!atomic_read(&dev->simple_cmds))
1793                         return false;
1794                 break;
1795         default:
1796                 /*
1797                  * For SIMPLE and UNTAGGED Task Attribute commands
1798                  */
1799                 atomic_inc_mb(&dev->simple_cmds);
1800                 break;
1801         }
1802
1803         if (atomic_read(&dev->dev_ordered_sync) == 0)
1804                 return false;
1805
1806         spin_lock(&dev->delayed_cmd_lock);
1807         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1808         spin_unlock(&dev->delayed_cmd_lock);
1809
1810         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1811                 " delayed CMD list, se_ordered_id: %u\n",
1812                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1813                 cmd->se_ordered_id);
1814         return true;
1815 }
1816
1817 void target_execute_cmd(struct se_cmd *cmd)
1818 {
1819         /*
1820          * If the received CDB has aleady been aborted stop processing it here.
1821          */
1822         if (transport_check_aborted_status(cmd, 1))
1823                 return;
1824
1825         /*
1826          * Determine if frontend context caller is requesting the stopping of
1827          * this command for frontend exceptions.
1828          */
1829         spin_lock_irq(&cmd->t_state_lock);
1830         if (cmd->transport_state & CMD_T_STOP) {
1831                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1832                         __func__, __LINE__, cmd->tag);
1833
1834                 spin_unlock_irq(&cmd->t_state_lock);
1835                 complete_all(&cmd->t_transport_stop_comp);
1836                 return;
1837         }
1838
1839         cmd->t_state = TRANSPORT_PROCESSING;
1840         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1841         spin_unlock_irq(&cmd->t_state_lock);
1842
1843         if (target_write_prot_action(cmd))
1844                 return;
1845
1846         if (target_handle_task_attr(cmd)) {
1847                 spin_lock_irq(&cmd->t_state_lock);
1848                 cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1849                 spin_unlock_irq(&cmd->t_state_lock);
1850                 return;
1851         }
1852
1853         __target_execute_cmd(cmd);
1854 }
1855 EXPORT_SYMBOL(target_execute_cmd);
1856
1857 /*
1858  * Process all commands up to the last received ORDERED task attribute which
1859  * requires another blocking boundary
1860  */
1861 static void target_restart_delayed_cmds(struct se_device *dev)
1862 {
1863         for (;;) {
1864                 struct se_cmd *cmd;
1865
1866                 spin_lock(&dev->delayed_cmd_lock);
1867                 if (list_empty(&dev->delayed_cmd_list)) {
1868                         spin_unlock(&dev->delayed_cmd_lock);
1869                         break;
1870                 }
1871
1872                 cmd = list_entry(dev->delayed_cmd_list.next,
1873                                  struct se_cmd, se_delayed_node);
1874                 list_del(&cmd->se_delayed_node);
1875                 spin_unlock(&dev->delayed_cmd_lock);
1876
1877                 __target_execute_cmd(cmd);
1878
1879                 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1880                         break;
1881         }
1882 }
1883
1884 /*
1885  * Called from I/O completion to determine which dormant/delayed
1886  * and ordered cmds need to have their tasks added to the execution queue.
1887  */
1888 static void transport_complete_task_attr(struct se_cmd *cmd)
1889 {
1890         struct se_device *dev = cmd->se_dev;
1891
1892         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1893                 return;
1894
1895         if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1896                 atomic_dec_mb(&dev->simple_cmds);
1897                 dev->dev_cur_ordered_id++;
1898                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1899                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1900                         cmd->se_ordered_id);
1901         } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1902                 dev->dev_cur_ordered_id++;
1903                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1904                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1905                         cmd->se_ordered_id);
1906         } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1907                 atomic_dec_mb(&dev->dev_ordered_sync);
1908
1909                 dev->dev_cur_ordered_id++;
1910                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1911                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1912         }
1913
1914         target_restart_delayed_cmds(dev);
1915 }
1916
1917 static void transport_complete_qf(struct se_cmd *cmd)
1918 {
1919         int ret = 0;
1920
1921         transport_complete_task_attr(cmd);
1922
1923         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1924                 trace_target_cmd_complete(cmd);
1925                 ret = cmd->se_tfo->queue_status(cmd);
1926                 goto out;
1927         }
1928
1929         switch (cmd->data_direction) {
1930         case DMA_FROM_DEVICE:
1931                 trace_target_cmd_complete(cmd);
1932                 ret = cmd->se_tfo->queue_data_in(cmd);
1933                 break;
1934         case DMA_TO_DEVICE:
1935                 if (cmd->se_cmd_flags & SCF_BIDI) {
1936                         ret = cmd->se_tfo->queue_data_in(cmd);
1937                         break;
1938                 }
1939                 /* Fall through for DMA_TO_DEVICE */
1940         case DMA_NONE:
1941                 trace_target_cmd_complete(cmd);
1942                 ret = cmd->se_tfo->queue_status(cmd);
1943                 break;
1944         default:
1945                 break;
1946         }
1947
1948 out:
1949         if (ret < 0) {
1950                 transport_handle_queue_full(cmd, cmd->se_dev);
1951                 return;
1952         }
1953         transport_lun_remove_cmd(cmd);
1954         transport_cmd_check_stop_to_fabric(cmd);
1955 }
1956
1957 static void transport_handle_queue_full(
1958         struct se_cmd *cmd,
1959         struct se_device *dev)
1960 {
1961         spin_lock_irq(&dev->qf_cmd_lock);
1962         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1963         atomic_inc_mb(&dev->dev_qf_count);
1964         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1965
1966         schedule_work(&cmd->se_dev->qf_work_queue);
1967 }
1968
1969 static bool target_read_prot_action(struct se_cmd *cmd)
1970 {
1971         switch (cmd->prot_op) {
1972         case TARGET_PROT_DIN_STRIP:
1973                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
1974                         u32 sectors = cmd->data_length >>
1975                                   ilog2(cmd->se_dev->dev_attrib.block_size);
1976
1977                         cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1978                                                      sectors, 0, cmd->t_prot_sg,
1979                                                      0);
1980                         if (cmd->pi_err)
1981                                 return true;
1982                 }
1983                 break;
1984         case TARGET_PROT_DIN_INSERT:
1985                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
1986                         break;
1987
1988                 sbc_dif_generate(cmd);
1989                 break;
1990         default:
1991                 break;
1992         }
1993
1994         return false;
1995 }
1996
1997 static void target_complete_ok_work(struct work_struct *work)
1998 {
1999         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2000         int ret;
2001
2002         /*
2003          * Check if we need to move delayed/dormant tasks from cmds on the
2004          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2005          * Attribute.
2006          */
2007         transport_complete_task_attr(cmd);
2008
2009         /*
2010          * Check to schedule QUEUE_FULL work, or execute an existing
2011          * cmd->transport_qf_callback()
2012          */
2013         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2014                 schedule_work(&cmd->se_dev->qf_work_queue);
2015
2016         /*
2017          * Check if we need to send a sense buffer from
2018          * the struct se_cmd in question.
2019          */
2020         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2021                 WARN_ON(!cmd->scsi_status);
2022                 ret = transport_send_check_condition_and_sense(
2023                                         cmd, 0, 1);
2024                 if (ret == -EAGAIN || ret == -ENOMEM)
2025                         goto queue_full;
2026
2027                 transport_lun_remove_cmd(cmd);
2028                 transport_cmd_check_stop_to_fabric(cmd);
2029                 return;
2030         }
2031         /*
2032          * Check for a callback, used by amongst other things
2033          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2034          */
2035         if (cmd->transport_complete_callback) {
2036                 sense_reason_t rc;
2037
2038                 rc = cmd->transport_complete_callback(cmd, true);
2039                 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
2040                         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2041                             !cmd->data_length)
2042                                 goto queue_rsp;
2043
2044                         return;
2045                 } else if (rc) {
2046                         ret = transport_send_check_condition_and_sense(cmd,
2047                                                 rc, 0);
2048                         if (ret == -EAGAIN || ret == -ENOMEM)
2049                                 goto queue_full;
2050
2051                         transport_lun_remove_cmd(cmd);
2052                         transport_cmd_check_stop_to_fabric(cmd);
2053                         return;
2054                 }
2055         }
2056
2057 queue_rsp:
2058         switch (cmd->data_direction) {
2059         case DMA_FROM_DEVICE:
2060                 atomic_long_add(cmd->data_length,
2061                                 &cmd->se_lun->lun_stats.tx_data_octets);
2062                 /*
2063                  * Perform READ_STRIP of PI using software emulation when
2064                  * backend had PI enabled, if the transport will not be
2065                  * performing hardware READ_STRIP offload.
2066                  */
2067                 if (target_read_prot_action(cmd)) {
2068                         ret = transport_send_check_condition_and_sense(cmd,
2069                                                 cmd->pi_err, 0);
2070                         if (ret == -EAGAIN || ret == -ENOMEM)
2071                                 goto queue_full;
2072
2073                         transport_lun_remove_cmd(cmd);
2074                         transport_cmd_check_stop_to_fabric(cmd);
2075                         return;
2076                 }
2077
2078                 trace_target_cmd_complete(cmd);
2079                 ret = cmd->se_tfo->queue_data_in(cmd);
2080                 if (ret == -EAGAIN || ret == -ENOMEM)
2081                         goto queue_full;
2082                 break;
2083         case DMA_TO_DEVICE:
2084                 atomic_long_add(cmd->data_length,
2085                                 &cmd->se_lun->lun_stats.rx_data_octets);
2086                 /*
2087                  * Check if we need to send READ payload for BIDI-COMMAND
2088                  */
2089                 if (cmd->se_cmd_flags & SCF_BIDI) {
2090                         atomic_long_add(cmd->data_length,
2091                                         &cmd->se_lun->lun_stats.tx_data_octets);
2092                         ret = cmd->se_tfo->queue_data_in(cmd);
2093                         if (ret == -EAGAIN || ret == -ENOMEM)
2094                                 goto queue_full;
2095                         break;
2096                 }
2097                 /* Fall through for DMA_TO_DEVICE */
2098         case DMA_NONE:
2099                 trace_target_cmd_complete(cmd);
2100                 ret = cmd->se_tfo->queue_status(cmd);
2101                 if (ret == -EAGAIN || ret == -ENOMEM)
2102                         goto queue_full;
2103                 break;
2104         default:
2105                 break;
2106         }
2107
2108         transport_lun_remove_cmd(cmd);
2109         transport_cmd_check_stop_to_fabric(cmd);
2110         return;
2111
2112 queue_full:
2113         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2114                 " data_direction: %d\n", cmd, cmd->data_direction);
2115         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2116         transport_handle_queue_full(cmd, cmd->se_dev);
2117 }
2118
2119 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2120 {
2121         struct scatterlist *sg;
2122         int count;
2123
2124         for_each_sg(sgl, sg, nents, count)
2125                 __free_page(sg_page(sg));
2126
2127         kfree(sgl);
2128 }
2129
2130 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2131 {
2132         /*
2133          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2134          * emulation, and free + reset pointers if necessary..
2135          */
2136         if (!cmd->t_data_sg_orig)
2137                 return;
2138
2139         kfree(cmd->t_data_sg);
2140         cmd->t_data_sg = cmd->t_data_sg_orig;
2141         cmd->t_data_sg_orig = NULL;
2142         cmd->t_data_nents = cmd->t_data_nents_orig;
2143         cmd->t_data_nents_orig = 0;
2144 }
2145
2146 static inline void transport_free_pages(struct se_cmd *cmd)
2147 {
2148         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2149                 transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2150                 cmd->t_prot_sg = NULL;
2151                 cmd->t_prot_nents = 0;
2152         }
2153
2154         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2155                 /*
2156                  * Release special case READ buffer payload required for
2157                  * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2158                  */
2159                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2160                         transport_free_sgl(cmd->t_bidi_data_sg,
2161                                            cmd->t_bidi_data_nents);
2162                         cmd->t_bidi_data_sg = NULL;
2163                         cmd->t_bidi_data_nents = 0;
2164                 }
2165                 transport_reset_sgl_orig(cmd);
2166                 return;
2167         }
2168         transport_reset_sgl_orig(cmd);
2169
2170         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2171         cmd->t_data_sg = NULL;
2172         cmd->t_data_nents = 0;
2173
2174         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2175         cmd->t_bidi_data_sg = NULL;
2176         cmd->t_bidi_data_nents = 0;
2177 }
2178
2179 /**
2180  * transport_release_cmd - free a command
2181  * @cmd:       command to free
2182  *
2183  * This routine unconditionally frees a command, and reference counting
2184  * or list removal must be done in the caller.
2185  */
2186 static int transport_release_cmd(struct se_cmd *cmd)
2187 {
2188         BUG_ON(!cmd->se_tfo);
2189
2190         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2191                 core_tmr_release_req(cmd->se_tmr_req);
2192         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2193                 kfree(cmd->t_task_cdb);
2194         /*
2195          * If this cmd has been setup with target_get_sess_cmd(), drop
2196          * the kref and call ->release_cmd() in kref callback.
2197          */
2198         return target_put_sess_cmd(cmd);
2199 }
2200
2201 /**
2202  * transport_put_cmd - release a reference to a command
2203  * @cmd:       command to release
2204  *
2205  * This routine releases our reference to the command and frees it if possible.
2206  */
2207 static int transport_put_cmd(struct se_cmd *cmd)
2208 {
2209         transport_free_pages(cmd);
2210         return transport_release_cmd(cmd);
2211 }
2212
2213 void *transport_kmap_data_sg(struct se_cmd *cmd)
2214 {
2215         struct scatterlist *sg = cmd->t_data_sg;
2216         struct page **pages;
2217         int i;
2218
2219         /*
2220          * We need to take into account a possible offset here for fabrics like
2221          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2222          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2223          */
2224         if (!cmd->t_data_nents)
2225                 return NULL;
2226
2227         BUG_ON(!sg);
2228         if (cmd->t_data_nents == 1)
2229                 return kmap(sg_page(sg)) + sg->offset;
2230
2231         /* >1 page. use vmap */
2232         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2233         if (!pages)
2234                 return NULL;
2235
2236         /* convert sg[] to pages[] */
2237         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2238                 pages[i] = sg_page(sg);
2239         }
2240
2241         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2242         kfree(pages);
2243         if (!cmd->t_data_vmap)
2244                 return NULL;
2245
2246         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2247 }
2248 EXPORT_SYMBOL(transport_kmap_data_sg);
2249
2250 void transport_kunmap_data_sg(struct se_cmd *cmd)
2251 {
2252         if (!cmd->t_data_nents) {
2253                 return;
2254         } else if (cmd->t_data_nents == 1) {
2255                 kunmap(sg_page(cmd->t_data_sg));
2256                 return;
2257         }
2258
2259         vunmap(cmd->t_data_vmap);
2260         cmd->t_data_vmap = NULL;
2261 }
2262 EXPORT_SYMBOL(transport_kunmap_data_sg);
2263
2264 int
2265 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2266                  bool zero_page)
2267 {
2268         struct scatterlist *sg;
2269         struct page *page;
2270         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2271         unsigned int nent;
2272         int i = 0;
2273
2274         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2275         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2276         if (!sg)
2277                 return -ENOMEM;
2278
2279         sg_init_table(sg, nent);
2280
2281         while (length) {
2282                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2283                 page = alloc_page(GFP_KERNEL | zero_flag);
2284                 if (!page)
2285                         goto out;
2286
2287                 sg_set_page(&sg[i], page, page_len, 0);
2288                 length -= page_len;
2289                 i++;
2290         }
2291         *sgl = sg;
2292         *nents = nent;
2293         return 0;
2294
2295 out:
2296         while (i > 0) {
2297                 i--;
2298                 __free_page(sg_page(&sg[i]));
2299         }
2300         kfree(sg);
2301         return -ENOMEM;
2302 }
2303
2304 /*
2305  * Allocate any required resources to execute the command.  For writes we
2306  * might not have the payload yet, so notify the fabric via a call to
2307  * ->write_pending instead. Otherwise place it on the execution queue.
2308  */
2309 sense_reason_t
2310 transport_generic_new_cmd(struct se_cmd *cmd)
2311 {
2312         int ret = 0;
2313         bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2314
2315         if (cmd->prot_op != TARGET_PROT_NORMAL &&
2316             !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2317                 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2318                                        cmd->prot_length, true);
2319                 if (ret < 0)
2320                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2321         }
2322
2323         /*
2324          * Determine is the TCM fabric module has already allocated physical
2325          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2326          * beforehand.
2327          */
2328         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2329             cmd->data_length) {
2330
2331                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2332                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2333                         u32 bidi_length;
2334
2335                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2336                                 bidi_length = cmd->t_task_nolb *
2337                                               cmd->se_dev->dev_attrib.block_size;
2338                         else
2339                                 bidi_length = cmd->data_length;
2340
2341                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2342                                                &cmd->t_bidi_data_nents,
2343                                                bidi_length, zero_flag);
2344                         if (ret < 0)
2345                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2346                 }
2347
2348                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2349                                        cmd->data_length, zero_flag);
2350                 if (ret < 0)
2351                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2352         } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2353                     cmd->data_length) {
2354                 /*
2355                  * Special case for COMPARE_AND_WRITE with fabrics
2356                  * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2357                  */
2358                 u32 caw_length = cmd->t_task_nolb *
2359                                  cmd->se_dev->dev_attrib.block_size;
2360
2361                 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2362                                        &cmd->t_bidi_data_nents,
2363                                        caw_length, zero_flag);
2364                 if (ret < 0)
2365                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2366         }
2367         /*
2368          * If this command is not a write we can execute it right here,
2369          * for write buffers we need to notify the fabric driver first
2370          * and let it call back once the write buffers are ready.
2371          */
2372         target_add_to_state_list(cmd);
2373         if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2374                 target_execute_cmd(cmd);
2375                 return 0;
2376         }
2377         transport_cmd_check_stop(cmd, false, true);
2378
2379         ret = cmd->se_tfo->write_pending(cmd);
2380         if (ret == -EAGAIN || ret == -ENOMEM)
2381                 goto queue_full;
2382
2383         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2384         WARN_ON(ret);
2385
2386         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2387
2388 queue_full:
2389         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2390         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2391         transport_handle_queue_full(cmd, cmd->se_dev);
2392         return 0;
2393 }
2394 EXPORT_SYMBOL(transport_generic_new_cmd);
2395
2396 static void transport_write_pending_qf(struct se_cmd *cmd)
2397 {
2398         int ret;
2399
2400         ret = cmd->se_tfo->write_pending(cmd);
2401         if (ret == -EAGAIN || ret == -ENOMEM) {
2402                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2403                          cmd);
2404                 transport_handle_queue_full(cmd, cmd->se_dev);
2405         }
2406 }
2407
2408 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2409 {
2410         unsigned long flags;
2411         int ret = 0;
2412
2413         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2414                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2415                          transport_wait_for_tasks(cmd);
2416
2417                 ret = transport_release_cmd(cmd);
2418         } else {
2419                 if (wait_for_tasks)
2420                         transport_wait_for_tasks(cmd);
2421                 /*
2422                  * Handle WRITE failure case where transport_generic_new_cmd()
2423                  * has already added se_cmd to state_list, but fabric has
2424                  * failed command before I/O submission.
2425                  */
2426                 if (cmd->state_active) {
2427                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2428                         target_remove_from_state_list(cmd);
2429                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2430                 }
2431
2432                 if (cmd->se_lun)
2433                         transport_lun_remove_cmd(cmd);
2434
2435                 ret = transport_put_cmd(cmd);
2436         }
2437         return ret;
2438 }
2439 EXPORT_SYMBOL(transport_generic_free_cmd);
2440
2441 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2442  * @se_cmd:     command descriptor to add
2443  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2444  */
2445 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2446 {
2447         struct se_session *se_sess = se_cmd->se_sess;
2448         unsigned long flags;
2449         int ret = 0;
2450
2451         /*
2452          * Add a second kref if the fabric caller is expecting to handle
2453          * fabric acknowledgement that requires two target_put_sess_cmd()
2454          * invocations before se_cmd descriptor release.
2455          */
2456         if (ack_kref)
2457                 kref_get(&se_cmd->cmd_kref);
2458
2459         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2460         if (se_sess->sess_tearing_down) {
2461                 ret = -ESHUTDOWN;
2462                 goto out;
2463         }
2464         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2465 out:
2466         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2467
2468         if (ret && ack_kref)
2469                 target_put_sess_cmd(se_cmd);
2470
2471         return ret;
2472 }
2473 EXPORT_SYMBOL(target_get_sess_cmd);
2474
2475 static void target_release_cmd_kref(struct kref *kref)
2476                 __releases(&se_cmd->se_sess->sess_cmd_lock)
2477 {
2478         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2479         struct se_session *se_sess = se_cmd->se_sess;
2480
2481         if (list_empty(&se_cmd->se_cmd_list)) {
2482                 spin_unlock(&se_sess->sess_cmd_lock);
2483                 se_cmd->se_tfo->release_cmd(se_cmd);
2484                 return;
2485         }
2486         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2487                 spin_unlock(&se_sess->sess_cmd_lock);
2488                 complete(&se_cmd->cmd_wait_comp);
2489                 return;
2490         }
2491         list_del(&se_cmd->se_cmd_list);
2492         spin_unlock(&se_sess->sess_cmd_lock);
2493
2494         se_cmd->se_tfo->release_cmd(se_cmd);
2495 }
2496
2497 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2498  * @se_cmd:     command descriptor to drop
2499  */
2500 int target_put_sess_cmd(struct se_cmd *se_cmd)
2501 {
2502         struct se_session *se_sess = se_cmd->se_sess;
2503
2504         if (!se_sess) {
2505                 se_cmd->se_tfo->release_cmd(se_cmd);
2506                 return 1;
2507         }
2508         return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2509                         &se_sess->sess_cmd_lock);
2510 }
2511 EXPORT_SYMBOL(target_put_sess_cmd);
2512
2513 /* target_sess_cmd_list_set_waiting - Flag all commands in
2514  *         sess_cmd_list to complete cmd_wait_comp.  Set
2515  *         sess_tearing_down so no more commands are queued.
2516  * @se_sess:    session to flag
2517  */
2518 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2519 {
2520         struct se_cmd *se_cmd;
2521         unsigned long flags;
2522
2523         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2524         if (se_sess->sess_tearing_down) {
2525                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2526                 return;
2527         }
2528         se_sess->sess_tearing_down = 1;
2529         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2530
2531         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2532                 se_cmd->cmd_wait_set = 1;
2533
2534         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2535 }
2536 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2537
2538 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2539  * @se_sess:    session to wait for active I/O
2540  */
2541 void target_wait_for_sess_cmds(struct se_session *se_sess)
2542 {
2543         struct se_cmd *se_cmd, *tmp_cmd;
2544         unsigned long flags;
2545
2546         list_for_each_entry_safe(se_cmd, tmp_cmd,
2547                                 &se_sess->sess_wait_list, se_cmd_list) {
2548                 list_del(&se_cmd->se_cmd_list);
2549
2550                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2551                         " %d\n", se_cmd, se_cmd->t_state,
2552                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2553
2554                 wait_for_completion(&se_cmd->cmd_wait_comp);
2555                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2556                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2557                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2558
2559                 se_cmd->se_tfo->release_cmd(se_cmd);
2560         }
2561
2562         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2563         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2564         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2565
2566 }
2567 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2568
2569 void transport_clear_lun_ref(struct se_lun *lun)
2570 {
2571         percpu_ref_kill(&lun->lun_ref);
2572         wait_for_completion(&lun->lun_ref_comp);
2573 }
2574
2575 /**
2576  * transport_wait_for_tasks - wait for completion to occur
2577  * @cmd:        command to wait
2578  *
2579  * Called from frontend fabric context to wait for storage engine
2580  * to pause and/or release frontend generated struct se_cmd.
2581  */
2582 bool transport_wait_for_tasks(struct se_cmd *cmd)
2583 {
2584         unsigned long flags;
2585
2586         spin_lock_irqsave(&cmd->t_state_lock, flags);
2587         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2588             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2589                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2590                 return false;
2591         }
2592
2593         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2594             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2595                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2596                 return false;
2597         }
2598
2599         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2600                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2601                 return false;
2602         }
2603
2604         cmd->transport_state |= CMD_T_STOP;
2605
2606         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08llx i_state: %d, t_state: %d, CMD_T_STOP\n",
2607                 cmd, cmd->tag, cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2608
2609         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2610
2611         wait_for_completion(&cmd->t_transport_stop_comp);
2612
2613         spin_lock_irqsave(&cmd->t_state_lock, flags);
2614         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2615
2616         pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->t_transport_stop_comp) for ITT: 0x%08llx\n",
2617                 cmd->tag);
2618
2619         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2620
2621         return true;
2622 }
2623 EXPORT_SYMBOL(transport_wait_for_tasks);
2624
2625 static int transport_get_sense_codes(
2626         struct se_cmd *cmd,
2627         u8 *asc,
2628         u8 *ascq)
2629 {
2630         *asc = cmd->scsi_asc;
2631         *ascq = cmd->scsi_ascq;
2632
2633         return 0;
2634 }
2635
2636 static
2637 void transport_err_sector_info(unsigned char *buffer, sector_t bad_sector)
2638 {
2639         /* Place failed LBA in sense data information descriptor 0. */
2640         buffer[SPC_ADD_SENSE_LEN_OFFSET] = 0xc;
2641         buffer[SPC_DESC_TYPE_OFFSET] = 0; /* Information */
2642         buffer[SPC_ADDITIONAL_DESC_LEN_OFFSET] = 0xa;
2643         buffer[SPC_VALIDITY_OFFSET] = 0x80;
2644
2645         /* Descriptor Information: failing sector */
2646         put_unaligned_be64(bad_sector, &buffer[12]);
2647 }
2648
2649 int
2650 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2651                 sense_reason_t reason, int from_transport)
2652 {
2653         unsigned char *buffer = cmd->sense_buffer;
2654         unsigned long flags;
2655         u8 asc = 0, ascq = 0;
2656
2657         spin_lock_irqsave(&cmd->t_state_lock, flags);
2658         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2659                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2660                 return 0;
2661         }
2662         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2663         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2664
2665         if (!reason && from_transport)
2666                 goto after_reason;
2667
2668         if (!from_transport)
2669                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2670
2671         /*
2672          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2673          * SENSE KEY values from include/scsi/scsi.h
2674          */
2675         switch (reason) {
2676         case TCM_NO_SENSE:
2677                 /* CURRENT ERROR */
2678                 buffer[0] = 0x70;
2679                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2680                 /* Not Ready */
2681                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2682                 /* NO ADDITIONAL SENSE INFORMATION */
2683                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2684                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2685                 break;
2686         case TCM_NON_EXISTENT_LUN:
2687                 /* CURRENT ERROR */
2688                 buffer[0] = 0x70;
2689                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2690                 /* ILLEGAL REQUEST */
2691                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2692                 /* LOGICAL UNIT NOT SUPPORTED */
2693                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2694                 break;
2695         case TCM_UNSUPPORTED_SCSI_OPCODE:
2696         case TCM_SECTOR_COUNT_TOO_MANY:
2697                 /* CURRENT ERROR */
2698                 buffer[0] = 0x70;
2699                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2700                 /* ILLEGAL REQUEST */
2701                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2702                 /* INVALID COMMAND OPERATION CODE */
2703                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2704                 break;
2705         case TCM_UNKNOWN_MODE_PAGE:
2706                 /* CURRENT ERROR */
2707                 buffer[0] = 0x70;
2708                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2709                 /* ILLEGAL REQUEST */
2710                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2711                 /* INVALID FIELD IN CDB */
2712                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2713                 break;
2714         case TCM_CHECK_CONDITION_ABORT_CMD:
2715                 /* CURRENT ERROR */
2716                 buffer[0] = 0x70;
2717                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2718                 /* ABORTED COMMAND */
2719                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2720                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2721                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2722                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2723                 break;
2724         case TCM_INCORRECT_AMOUNT_OF_DATA:
2725                 /* CURRENT ERROR */
2726                 buffer[0] = 0x70;
2727                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2728                 /* ABORTED COMMAND */
2729                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2730                 /* WRITE ERROR */
2731                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2732                 /* NOT ENOUGH UNSOLICITED DATA */
2733                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2734                 break;
2735         case TCM_INVALID_CDB_FIELD:
2736                 /* CURRENT ERROR */
2737                 buffer[0] = 0x70;
2738                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2739                 /* ILLEGAL REQUEST */
2740                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2741                 /* INVALID FIELD IN CDB */
2742                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2743                 break;
2744         case TCM_INVALID_PARAMETER_LIST:
2745                 /* CURRENT ERROR */
2746                 buffer[0] = 0x70;
2747                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2748                 /* ILLEGAL REQUEST */
2749                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2750                 /* INVALID FIELD IN PARAMETER LIST */
2751                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2752                 break;
2753         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2754                 /* CURRENT ERROR */
2755                 buffer[0] = 0x70;
2756                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2757                 /* ILLEGAL REQUEST */
2758                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2759                 /* PARAMETER LIST LENGTH ERROR */
2760                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2761                 break;
2762         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2763                 /* CURRENT ERROR */
2764                 buffer[0] = 0x70;
2765                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2766                 /* ABORTED COMMAND */
2767                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2768                 /* WRITE ERROR */
2769                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2770                 /* UNEXPECTED_UNSOLICITED_DATA */
2771                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2772                 break;
2773         case TCM_SERVICE_CRC_ERROR:
2774                 /* CURRENT ERROR */
2775                 buffer[0] = 0x70;
2776                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2777                 /* ABORTED COMMAND */
2778                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2779                 /* PROTOCOL SERVICE CRC ERROR */
2780                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2781                 /* N/A */
2782                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2783                 break;
2784         case TCM_SNACK_REJECTED:
2785                 /* CURRENT ERROR */
2786                 buffer[0] = 0x70;
2787                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2788                 /* ABORTED COMMAND */
2789                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2790                 /* READ ERROR */
2791                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2792                 /* FAILED RETRANSMISSION REQUEST */
2793                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2794                 break;
2795         case TCM_WRITE_PROTECTED:
2796                 /* CURRENT ERROR */
2797                 buffer[0] = 0x70;
2798                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2799                 /* DATA PROTECT */
2800                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2801                 /* WRITE PROTECTED */
2802                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2803                 break;
2804         case TCM_ADDRESS_OUT_OF_RANGE:
2805                 /* CURRENT ERROR */
2806                 buffer[0] = 0x70;
2807                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2808                 /* ILLEGAL REQUEST */
2809                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2810                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2811                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2812                 break;
2813         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2814                 /* CURRENT ERROR */
2815                 buffer[0] = 0x70;
2816                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2817                 /* UNIT ATTENTION */
2818                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2819                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2820                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2821                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2822                 break;
2823         case TCM_CHECK_CONDITION_NOT_READY:
2824                 /* CURRENT ERROR */
2825                 buffer[0] = 0x70;
2826                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2827                 /* Not Ready */
2828                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2829                 transport_get_sense_codes(cmd, &asc, &ascq);
2830                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2831                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2832                 break;
2833         case TCM_MISCOMPARE_VERIFY:
2834                 /* CURRENT ERROR */
2835                 buffer[0] = 0x70;
2836                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2837                 buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
2838                 /* MISCOMPARE DURING VERIFY OPERATION */
2839                 buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
2840                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
2841                 break;
2842         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
2843                 /* CURRENT ERROR */
2844                 buffer[0] = 0x70;
2845                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2846                 /* ILLEGAL REQUEST */
2847                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2848                 /* LOGICAL BLOCK GUARD CHECK FAILED */
2849                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2850                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x01;
2851                 transport_err_sector_info(buffer, cmd->bad_sector);
2852                 break;
2853         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
2854                 /* CURRENT ERROR */
2855                 buffer[0] = 0x70;
2856                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2857                 /* ILLEGAL REQUEST */
2858                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2859                 /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2860                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2861                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x02;
2862                 transport_err_sector_info(buffer, cmd->bad_sector);
2863                 break;
2864         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
2865                 /* CURRENT ERROR */
2866                 buffer[0] = 0x70;
2867                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2868                 /* ILLEGAL REQUEST */
2869                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2870                 /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2871                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2872                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2873                 transport_err_sector_info(buffer, cmd->bad_sector);
2874                 break;
2875         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2876         default:
2877                 /* CURRENT ERROR */
2878                 buffer[0] = 0x70;
2879                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2880                 /*
2881                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2882                  * Solaris initiators.  Returning NOT READY instead means the
2883                  * operations will be retried a finite number of times and we
2884                  * can survive intermittent errors.
2885                  */
2886                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2887                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2888                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2889                 break;
2890         }
2891         /*
2892          * This code uses linux/include/scsi/scsi.h SAM status codes!
2893          */
2894         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2895         /*
2896          * Automatically padded, this value is encoded in the fabric's
2897          * data_length response PDU containing the SCSI defined sense data.
2898          */
2899         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2900
2901 after_reason:
2902         trace_target_cmd_complete(cmd);
2903         return cmd->se_tfo->queue_status(cmd);
2904 }
2905 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2906
2907 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2908 {
2909         if (!(cmd->transport_state & CMD_T_ABORTED))
2910                 return 0;
2911
2912         /*
2913          * If cmd has been aborted but either no status is to be sent or it has
2914          * already been sent, just return
2915          */
2916         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
2917                 return 1;
2918
2919         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08llx\n",
2920                  cmd->t_task_cdb[0], cmd->tag);
2921
2922         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2923         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2924         trace_target_cmd_complete(cmd);
2925         cmd->se_tfo->queue_status(cmd);
2926
2927         return 1;
2928 }
2929 EXPORT_SYMBOL(transport_check_aborted_status);
2930
2931 void transport_send_task_abort(struct se_cmd *cmd)
2932 {
2933         unsigned long flags;
2934
2935         spin_lock_irqsave(&cmd->t_state_lock, flags);
2936         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2937                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2938                 return;
2939         }
2940         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2941
2942         /*
2943          * If there are still expected incoming fabric WRITEs, we wait
2944          * until until they have completed before sending a TASK_ABORTED
2945          * response.  This response with TASK_ABORTED status will be
2946          * queued back to fabric module by transport_check_aborted_status().
2947          */
2948         if (cmd->data_direction == DMA_TO_DEVICE) {
2949                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2950                         cmd->transport_state |= CMD_T_ABORTED;
2951                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2952                         return;
2953                 }
2954         }
2955         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2956
2957         transport_lun_remove_cmd(cmd);
2958
2959         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
2960                  cmd->t_task_cdb[0], cmd->tag);
2961
2962         trace_target_cmd_complete(cmd);
2963         cmd->se_tfo->queue_status(cmd);
2964 }
2965
2966 static void target_tmr_work(struct work_struct *work)
2967 {
2968         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2969         struct se_device *dev = cmd->se_dev;
2970         struct se_tmr_req *tmr = cmd->se_tmr_req;
2971         int ret;
2972
2973         switch (tmr->function) {
2974         case TMR_ABORT_TASK:
2975                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2976                 break;
2977         case TMR_ABORT_TASK_SET:
2978         case TMR_CLEAR_ACA:
2979         case TMR_CLEAR_TASK_SET:
2980                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2981                 break;
2982         case TMR_LUN_RESET:
2983                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2984                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2985                                          TMR_FUNCTION_REJECTED;
2986                 break;
2987         case TMR_TARGET_WARM_RESET:
2988                 tmr->response = TMR_FUNCTION_REJECTED;
2989                 break;
2990         case TMR_TARGET_COLD_RESET:
2991                 tmr->response = TMR_FUNCTION_REJECTED;
2992                 break;
2993         default:
2994                 pr_err("Uknown TMR function: 0x%02x.\n",
2995                                 tmr->function);
2996                 tmr->response = TMR_FUNCTION_REJECTED;
2997                 break;
2998         }
2999
3000         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3001         cmd->se_tfo->queue_tm_rsp(cmd);
3002
3003         transport_cmd_check_stop_to_fabric(cmd);
3004 }
3005
3006 int transport_generic_handle_tmr(
3007         struct se_cmd *cmd)
3008 {
3009         unsigned long flags;
3010
3011         spin_lock_irqsave(&cmd->t_state_lock, flags);
3012         cmd->transport_state |= CMD_T_ACTIVE;
3013         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3014
3015         INIT_WORK(&cmd->work, target_tmr_work);
3016         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3017         return 0;
3018 }
3019 EXPORT_SYMBOL(transport_generic_handle_tmr);
3020
3021 bool
3022 target_check_wce(struct se_device *dev)
3023 {
3024         bool wce = false;
3025
3026         if (dev->transport->get_write_cache)
3027                 wce = dev->transport->get_write_cache(dev);
3028         else if (dev->dev_attrib.emulate_write_cache > 0)
3029                 wce = true;
3030
3031         return wce;
3032 }
3033
3034 bool
3035 target_check_fua(struct se_device *dev)
3036 {
3037         return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3038 }