drivers/target/target_core_transport.c

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