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->cpuid == -1)
 715                 queue_work(target_completion_wq, &cmd->work);
 716         else
 717                 queue_work_on(cmd->cpuid, 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         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1430                 se_cmd->unknown_data_length = 1;
1431         /*
1432          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1433          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1434          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1435          * kref_put() to happen during fabric packet acknowledgement.
1436          */
1437         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1438         if (ret)
1439                 return ret;
1440         /*
1441          * Signal bidirectional data payloads to target-core
1442          */
1443         if (flags & TARGET_SCF_BIDI_OP)
1444                 se_cmd->se_cmd_flags |= SCF_BIDI;
1445         /*
1446          * Locate se_lun pointer and attach it to struct se_cmd
1447          */
1448         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1449         if (rc) {
1450                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1451                 target_put_sess_cmd(se_cmd);
1452                 return 0;
1453         }
1454
1455         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1456         if (rc != 0) {
1457                 transport_generic_request_failure(se_cmd, rc);
1458                 return 0;
1459         }
1460
1461         /*
1462          * Save pointers for SGLs containing protection information,
1463          * if present.
1464          */
1465         if (sgl_prot_count) {
1466                 se_cmd->t_prot_sg = sgl_prot;
1467                 se_cmd->t_prot_nents = sgl_prot_count;
1468                 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1469         }
1470
1471         /*
1472          * When a non zero sgl_count has been passed perform SGL passthrough
1473          * mapping for pre-allocated fabric memory instead of having target
1474          * core perform an internal SGL allocation..
1475          */
1476         if (sgl_count != 0) {
1477                 BUG_ON(!sgl);
1478
1479                 /*
1480                  * A work-around for tcm_loop as some userspace code via
1481                  * scsi-generic do not memset their associated read buffers,
1482                  * so go ahead and do that here for type non-data CDBs.  Also
1483                  * note that this is currently guaranteed to be a single SGL
1484                  * for this case by target core in target_setup_cmd_from_cdb()
1485                  * -> transport_generic_cmd_sequencer().
1486                  */
1487                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1488                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1489                         unsigned char *buf = NULL;
1490
1491                         if (sgl)
1492                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1493
1494                         if (buf) {
1495                                 memset(buf, 0, sgl->length);
1496                                 kunmap(sg_page(sgl));
1497                         }
1498                 }
1499
1500                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1501                                 sgl_bidi, sgl_bidi_count);
1502                 if (rc != 0) {
1503                         transport_generic_request_failure(se_cmd, rc);
1504                         return 0;
1505                 }
1506         }
1507
1508         /*
1509          * Check if we need to delay processing because of ALUA
1510          * Active/NonOptimized primary access state..
1511          */
1512         core_alua_check_nonop_delay(se_cmd);
1513
1514         transport_handle_cdb_direct(se_cmd);
1515         return 0;
1516 }
1517 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1518
1519 /*
1520  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1521  *
1522  * @se_cmd: command descriptor to submit
1523  * @se_sess: associated se_sess for endpoint
1524  * @cdb: pointer to SCSI CDB
1525  * @sense: pointer to SCSI sense buffer
1526  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1527  * @data_length: fabric expected data transfer length
1528  * @task_addr: SAM task attribute
1529  * @data_dir: DMA data direction
1530  * @flags: flags for command submission from target_sc_flags_tables
1531  *
1532  * Task tags are supported if the caller has set @se_cmd->tag.
1533  *
1534  * Returns non zero to signal active I/O shutdown failure.  All other
1535  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1536  * but still return zero here.
1537  *
1538  * This may only be called from process context, and also currently
1539  * assumes internal allocation of fabric payload buffer by target-core.
1540  *
1541  * It also assumes interal target core SGL memory allocation.
1542  */
1543 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1544                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1545                 u32 data_length, int task_attr, int data_dir, int flags)
1546 {
1547         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1548                         unpacked_lun, data_length, task_attr, data_dir,
1549                         flags, NULL, 0, NULL, 0, NULL, 0);
1550 }
1551 EXPORT_SYMBOL(target_submit_cmd);
1552
1553 static void target_complete_tmr_failure(struct work_struct *work)
1554 {
1555         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1556
1557         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1558         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1559
1560         transport_cmd_check_stop_to_fabric(se_cmd);
1561 }
1562
1563 /**
1564  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1565  *                     for TMR CDBs
1566  *
1567  * @se_cmd: command descriptor to submit
1568  * @se_sess: associated se_sess for endpoint
1569  * @sense: pointer to SCSI sense buffer
1570  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1571  * @fabric_context: fabric context for TMR req
1572  * @tm_type: Type of TM request
1573  * @gfp: gfp type for caller
1574  * @tag: referenced task tag for TMR_ABORT_TASK
1575  * @flags: submit cmd flags
1576  *
1577  * Callable from all contexts.
1578  **/
1579
1580 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1581                 unsigned char *sense, u64 unpacked_lun,
1582                 void *fabric_tmr_ptr, unsigned char tm_type,
1583                 gfp_t gfp, u64 tag, int flags)
1584 {
1585         struct se_portal_group *se_tpg;
1586         int ret;
1587
1588         se_tpg = se_sess->se_tpg;
1589         BUG_ON(!se_tpg);
1590
1591         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1592                               0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1593         /*
1594          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1595          * allocation failure.
1596          */
1597         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1598         if (ret < 0)
1599                 return -ENOMEM;
1600
1601         if (tm_type == TMR_ABORT_TASK)
1602                 se_cmd->se_tmr_req->ref_task_tag = tag;
1603
1604         /* See target_submit_cmd for commentary */
1605         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1606         if (ret) {
1607                 core_tmr_release_req(se_cmd->se_tmr_req);
1608                 return ret;
1609         }
1610
1611         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1612         if (ret) {
1613                 /*
1614                  * For callback during failure handling, push this work off
1615                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1616                  */
1617                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1618                 schedule_work(&se_cmd->work);
1619                 return 0;
1620         }
1621         transport_generic_handle_tmr(se_cmd);
1622         return 0;
1623 }
1624 EXPORT_SYMBOL(target_submit_tmr);
1625
1626 /*
1627  * Handle SAM-esque emulation for generic transport request failures.
1628  */
1629 void transport_generic_request_failure(struct se_cmd *cmd,
1630                 sense_reason_t sense_reason)
1631 {
1632         int ret = 0, post_ret = 0;
1633
1634         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08llx"
1635                 " CDB: 0x%02x\n", cmd, cmd->tag, cmd->t_task_cdb[0]);
1636         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1637                 cmd->se_tfo->get_cmd_state(cmd),
1638                 cmd->t_state, sense_reason);
1639         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1640                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1641                 (cmd->transport_state & CMD_T_STOP) != 0,
1642                 (cmd->transport_state & CMD_T_SENT) != 0);
1643
1644         /*
1645          * For SAM Task Attribute emulation for failed struct se_cmd
1646          */
1647         transport_complete_task_attr(cmd);
1648         /*
1649          * Handle special case for COMPARE_AND_WRITE failure, where the
1650          * callback is expected to drop the per device ->caw_sem.
1651          */
1652         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1653              cmd->transport_complete_callback)
1654                 cmd->transport_complete_callback(cmd, false, &post_ret);
1655
1656         switch (sense_reason) {
1657         case TCM_NON_EXISTENT_LUN:
1658         case TCM_UNSUPPORTED_SCSI_OPCODE:
1659         case TCM_INVALID_CDB_FIELD:
1660         case TCM_INVALID_PARAMETER_LIST:
1661         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1662         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1663         case TCM_UNKNOWN_MODE_PAGE:
1664         case TCM_WRITE_PROTECTED:
1665         case TCM_ADDRESS_OUT_OF_RANGE:
1666         case TCM_CHECK_CONDITION_ABORT_CMD:
1667         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1668         case TCM_CHECK_CONDITION_NOT_READY:
1669         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1670         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1671         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1672                 break;
1673         case TCM_OUT_OF_RESOURCES:
1674                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1675                 break;
1676         case TCM_RESERVATION_CONFLICT:
1677                 /*
1678                  * No SENSE Data payload for this case, set SCSI Status
1679                  * and queue the response to $FABRIC_MOD.
1680                  *
1681                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1682                  */
1683                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1684                 /*
1685                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1686                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1687                  * CONFLICT STATUS.
1688                  *
1689                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1690                  */
1691                 if (cmd->se_sess &&
1692                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1693                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1694                                                cmd->orig_fe_lun, 0x2C,
1695                                         ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1696                 }
1697                 trace_target_cmd_complete(cmd);
1698                 ret = cmd->se_tfo->queue_status(cmd);
1699                 if (ret == -EAGAIN || ret == -ENOMEM)
1700                         goto queue_full;
1701                 goto check_stop;
1702         default:
1703                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1704                         cmd->t_task_cdb[0], sense_reason);
1705                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1706                 break;
1707         }
1708
1709         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1710         if (ret == -EAGAIN || ret == -ENOMEM)
1711                 goto queue_full;
1712
1713 check_stop:
1714         transport_lun_remove_cmd(cmd);
1715         transport_cmd_check_stop_to_fabric(cmd);
1716         return;
1717
1718 queue_full:
1719         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1720         transport_handle_queue_full(cmd, cmd->se_dev);
1721 }
1722 EXPORT_SYMBOL(transport_generic_request_failure);
1723
1724 void __target_execute_cmd(struct se_cmd *cmd)
1725 {
1726         sense_reason_t ret;
1727
1728         if (cmd->execute_cmd) {
1729                 ret = cmd->execute_cmd(cmd);
1730                 if (ret) {
1731                         spin_lock_irq(&cmd->t_state_lock);
1732                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1733                         spin_unlock_irq(&cmd->t_state_lock);
1734
1735                         transport_generic_request_failure(cmd, ret);
1736                 }
1737         }
1738 }
1739
1740 static int target_write_prot_action(struct se_cmd *cmd)
1741 {
1742         u32 sectors;
1743         /*
1744          * Perform WRITE_INSERT of PI using software emulation when backend
1745          * device has PI enabled, if the transport has not already generated
1746          * PI using hardware WRITE_INSERT offload.
1747          */
1748         switch (cmd->prot_op) {
1749         case TARGET_PROT_DOUT_INSERT:
1750                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1751                         sbc_dif_generate(cmd);
1752                 break;
1753         case TARGET_PROT_DOUT_STRIP:
1754                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1755                         break;
1756
1757                 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1758                 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1759                                              sectors, 0, cmd->t_prot_sg, 0);
1760                 if (unlikely(cmd->pi_err)) {
1761                         spin_lock_irq(&cmd->t_state_lock);
1762                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1763                         spin_unlock_irq(&cmd->t_state_lock);
1764                         transport_generic_request_failure(cmd, cmd->pi_err);
1765                         return -1;
1766                 }
1767                 break;
1768         default:
1769                 break;
1770         }
1771
1772         return 0;
1773 }
1774
1775 static bool target_handle_task_attr(struct se_cmd *cmd)
1776 {
1777         struct se_device *dev = cmd->se_dev;
1778
1779         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1780                 return false;
1781
1782         /*
1783          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1784          * to allow the passed struct se_cmd list of tasks to the front of the list.
1785          */
1786         switch (cmd->sam_task_attr) {
1787         case TCM_HEAD_TAG:
1788                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1789                          cmd->t_task_cdb[0]);
1790                 return false;
1791         case TCM_ORDERED_TAG:
1792                 atomic_inc_mb(&dev->dev_ordered_sync);
1793
1794                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1795                          cmd->t_task_cdb[0]);
1796
1797                 /*
1798                  * Execute an ORDERED command if no other older commands
1799                  * exist that need to be completed first.
1800                  */
1801                 if (!atomic_read(&dev->simple_cmds))
1802                         return false;
1803                 break;
1804         default:
1805                 /*
1806                  * For SIMPLE and UNTAGGED Task Attribute commands
1807                  */
1808                 atomic_inc_mb(&dev->simple_cmds);
1809                 break;
1810         }
1811
1812         if (atomic_read(&dev->dev_ordered_sync) == 0)
1813                 return false;
1814
1815         spin_lock(&dev->delayed_cmd_lock);
1816         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1817         spin_unlock(&dev->delayed_cmd_lock);
1818
1819         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
1820                 cmd->t_task_cdb[0], cmd->sam_task_attr);
1821         return true;
1822 }
1823
1824 static int __transport_check_aborted_status(struct se_cmd *, int);
1825
1826 void target_execute_cmd(struct se_cmd *cmd)
1827 {
1828         /*
1829          * Determine if frontend context caller is requesting the stopping of
1830          * this command for frontend exceptions.
1831          *
1832          * If the received CDB has aleady been aborted stop processing it here.
1833          */
1834         spin_lock_irq(&cmd->t_state_lock);
1835         if (__transport_check_aborted_status(cmd, 1)) {
1836                 spin_unlock_irq(&cmd->t_state_lock);
1837                 return;
1838         }
1839         if (cmd->transport_state & CMD_T_STOP) {
1840                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1841                         __func__, __LINE__, cmd->tag);
1842
1843                 spin_unlock_irq(&cmd->t_state_lock);
1844                 complete_all(&cmd->t_transport_stop_comp);
1845                 return;
1846         }
1847
1848         cmd->t_state = TRANSPORT_PROCESSING;
1849         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1850         spin_unlock_irq(&cmd->t_state_lock);
1851
1852         if (target_write_prot_action(cmd))
1853                 return;
1854
1855         if (target_handle_task_attr(cmd)) {
1856                 spin_lock_irq(&cmd->t_state_lock);
1857                 cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1858                 spin_unlock_irq(&cmd->t_state_lock);
1859                 return;
1860         }
1861
1862         __target_execute_cmd(cmd);
1863 }
1864 EXPORT_SYMBOL(target_execute_cmd);
1865
1866 /*
1867  * Process all commands up to the last received ORDERED task attribute which
1868  * requires another blocking boundary
1869  */
1870 static void target_restart_delayed_cmds(struct se_device *dev)
1871 {
1872         for (;;) {
1873                 struct se_cmd *cmd;
1874
1875                 spin_lock(&dev->delayed_cmd_lock);
1876                 if (list_empty(&dev->delayed_cmd_list)) {
1877                         spin_unlock(&dev->delayed_cmd_lock);
1878                         break;
1879                 }
1880
1881                 cmd = list_entry(dev->delayed_cmd_list.next,
1882                                  struct se_cmd, se_delayed_node);
1883                 list_del(&cmd->se_delayed_node);
1884                 spin_unlock(&dev->delayed_cmd_lock);
1885
1886                 __target_execute_cmd(cmd);
1887
1888                 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1889                         break;
1890         }
1891 }
1892
1893 /*
1894  * Called from I/O completion to determine which dormant/delayed
1895  * and ordered cmds need to have their tasks added to the execution queue.
1896  */
1897 static void transport_complete_task_attr(struct se_cmd *cmd)
1898 {
1899         struct se_device *dev = cmd->se_dev;
1900
1901         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1902                 return;
1903
1904         if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1905                 atomic_dec_mb(&dev->simple_cmds);
1906                 dev->dev_cur_ordered_id++;
1907                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for SIMPLE\n",
1908                          dev->dev_cur_ordered_id);
1909         } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1910                 dev->dev_cur_ordered_id++;
1911                 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
1912                          dev->dev_cur_ordered_id);
1913         } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1914                 atomic_dec_mb(&dev->dev_ordered_sync);
1915
1916                 dev->dev_cur_ordered_id++;
1917                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
1918                          dev->dev_cur_ordered_id);
1919         }
1920
1921         target_restart_delayed_cmds(dev);
1922 }
1923
1924 static void transport_complete_qf(struct se_cmd *cmd)
1925 {
1926         int ret = 0;
1927
1928         transport_complete_task_attr(cmd);
1929
1930         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1931                 trace_target_cmd_complete(cmd);
1932                 ret = cmd->se_tfo->queue_status(cmd);
1933                 goto out;
1934         }
1935
1936         switch (cmd->data_direction) {
1937         case DMA_FROM_DEVICE:
1938                 trace_target_cmd_complete(cmd);
1939                 ret = cmd->se_tfo->queue_data_in(cmd);
1940                 break;
1941         case DMA_TO_DEVICE:
1942                 if (cmd->se_cmd_flags & SCF_BIDI) {
1943                         ret = cmd->se_tfo->queue_data_in(cmd);
1944                         break;
1945                 }
1946                 /* Fall through for DMA_TO_DEVICE */
1947         case DMA_NONE:
1948                 trace_target_cmd_complete(cmd);
1949                 ret = cmd->se_tfo->queue_status(cmd);
1950                 break;
1951         default:
1952                 break;
1953         }
1954
1955 out:
1956         if (ret < 0) {
1957                 transport_handle_queue_full(cmd, cmd->se_dev);
1958                 return;
1959         }
1960         transport_lun_remove_cmd(cmd);
1961         transport_cmd_check_stop_to_fabric(cmd);
1962 }
1963
1964 static void transport_handle_queue_full(
1965         struct se_cmd *cmd,
1966         struct se_device *dev)
1967 {
1968         spin_lock_irq(&dev->qf_cmd_lock);
1969         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1970         atomic_inc_mb(&dev->dev_qf_count);
1971         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1972
1973         schedule_work(&cmd->se_dev->qf_work_queue);
1974 }
1975
1976 static bool target_read_prot_action(struct se_cmd *cmd)
1977 {
1978         switch (cmd->prot_op) {
1979         case TARGET_PROT_DIN_STRIP:
1980                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
1981                         u32 sectors = cmd->data_length >>
1982                                   ilog2(cmd->se_dev->dev_attrib.block_size);
1983
1984                         cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1985                                                      sectors, 0, cmd->t_prot_sg,
1986                                                      0);
1987                         if (cmd->pi_err)
1988                                 return true;
1989                 }
1990                 break;
1991         case TARGET_PROT_DIN_INSERT:
1992                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
1993                         break;
1994
1995                 sbc_dif_generate(cmd);
1996                 break;
1997         default:
1998                 break;
1999         }
2000
2001         return false;
2002 }
2003
2004 static void target_complete_ok_work(struct work_struct *work)
2005 {
2006         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2007         int ret;
2008
2009         /*
2010          * Check if we need to move delayed/dormant tasks from cmds on the
2011          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2012          * Attribute.
2013          */
2014         transport_complete_task_attr(cmd);
2015
2016         /*
2017          * Check to schedule QUEUE_FULL work, or execute an existing
2018          * cmd->transport_qf_callback()
2019          */
2020         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2021                 schedule_work(&cmd->se_dev->qf_work_queue);
2022
2023         /*
2024          * Check if we need to send a sense buffer from
2025          * the struct se_cmd in question.
2026          */
2027         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2028                 WARN_ON(!cmd->scsi_status);
2029                 ret = transport_send_check_condition_and_sense(
2030                                         cmd, 0, 1);
2031                 if (ret == -EAGAIN || ret == -ENOMEM)
2032                         goto queue_full;
2033
2034                 transport_lun_remove_cmd(cmd);
2035                 transport_cmd_check_stop_to_fabric(cmd);
2036                 return;
2037         }
2038         /*
2039          * Check for a callback, used by amongst other things
2040          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2041          */
2042         if (cmd->transport_complete_callback) {
2043                 sense_reason_t rc;
2044                 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2045                 bool zero_dl = !(cmd->data_length);
2046                 int post_ret = 0;
2047
2048                 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2049                 if (!rc && !post_ret) {
2050                         if (caw && zero_dl)
2051                                 goto queue_rsp;
2052
2053                         return;
2054                 } else if (rc) {
2055                         ret = transport_send_check_condition_and_sense(cmd,
2056                                                 rc, 0);
2057                         if (ret == -EAGAIN || ret == -ENOMEM)
2058                                 goto queue_full;
2059
2060                         transport_lun_remove_cmd(cmd);
2061                         transport_cmd_check_stop_to_fabric(cmd);
2062                         return;
2063                 }
2064         }
2065
2066 queue_rsp:
2067         switch (cmd->data_direction) {
2068         case DMA_FROM_DEVICE:
2069                 atomic_long_add(cmd->data_length,
2070                                 &cmd->se_lun->lun_stats.tx_data_octets);
2071                 /*
2072                  * Perform READ_STRIP of PI using software emulation when
2073                  * backend had PI enabled, if the transport will not be
2074                  * performing hardware READ_STRIP offload.
2075                  */
2076                 if (target_read_prot_action(cmd)) {
2077                         ret = transport_send_check_condition_and_sense(cmd,
2078                                                 cmd->pi_err, 0);
2079                         if (ret == -EAGAIN || ret == -ENOMEM)
2080                                 goto queue_full;
2081
2082                         transport_lun_remove_cmd(cmd);
2083                         transport_cmd_check_stop_to_fabric(cmd);
2084                         return;
2085                 }
2086
2087                 trace_target_cmd_complete(cmd);
2088                 ret = cmd->se_tfo->queue_data_in(cmd);
2089                 if (ret == -EAGAIN || ret == -ENOMEM)
2090                         goto queue_full;
2091                 break;
2092         case DMA_TO_DEVICE:
2093                 atomic_long_add(cmd->data_length,
2094                                 &cmd->se_lun->lun_stats.rx_data_octets);
2095                 /*
2096                  * Check if we need to send READ payload for BIDI-COMMAND
2097                  */
2098                 if (cmd->se_cmd_flags & SCF_BIDI) {
2099                         atomic_long_add(cmd->data_length,
2100                                         &cmd->se_lun->lun_stats.tx_data_octets);
2101                         ret = cmd->se_tfo->queue_data_in(cmd);
2102                         if (ret == -EAGAIN || ret == -ENOMEM)
2103                                 goto queue_full;
2104                         break;
2105                 }
2106                 /* Fall through for DMA_TO_DEVICE */
2107         case DMA_NONE:
2108                 trace_target_cmd_complete(cmd);
2109                 ret = cmd->se_tfo->queue_status(cmd);
2110                 if (ret == -EAGAIN || ret == -ENOMEM)
2111                         goto queue_full;
2112                 break;
2113         default:
2114                 break;
2115         }
2116
2117         transport_lun_remove_cmd(cmd);
2118         transport_cmd_check_stop_to_fabric(cmd);
2119         return;
2120
2121 queue_full:
2122         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2123                 " data_direction: %d\n", cmd, cmd->data_direction);
2124         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2125         transport_handle_queue_full(cmd, cmd->se_dev);
2126 }
2127
2128 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2129 {
2130         struct scatterlist *sg;
2131         int count;
2132
2133         for_each_sg(sgl, sg, nents, count)
2134                 __free_page(sg_page(sg));
2135
2136         kfree(sgl);
2137 }
2138
2139 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2140 {
2141         /*
2142          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2143          * emulation, and free + reset pointers if necessary..
2144          */
2145         if (!cmd->t_data_sg_orig)
2146                 return;
2147
2148         kfree(cmd->t_data_sg);
2149         cmd->t_data_sg = cmd->t_data_sg_orig;
2150         cmd->t_data_sg_orig = NULL;
2151         cmd->t_data_nents = cmd->t_data_nents_orig;
2152         cmd->t_data_nents_orig = 0;
2153 }
2154
2155 static inline void transport_free_pages(struct se_cmd *cmd)
2156 {
2157         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2158                 transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2159                 cmd->t_prot_sg = NULL;
2160                 cmd->t_prot_nents = 0;
2161         }
2162
2163         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2164                 /*
2165                  * Release special case READ buffer payload required for
2166                  * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2167                  */
2168                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2169                         transport_free_sgl(cmd->t_bidi_data_sg,
2170                                            cmd->t_bidi_data_nents);
2171                         cmd->t_bidi_data_sg = NULL;
2172                         cmd->t_bidi_data_nents = 0;
2173                 }
2174                 transport_reset_sgl_orig(cmd);
2175                 return;
2176         }
2177         transport_reset_sgl_orig(cmd);
2178
2179         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2180         cmd->t_data_sg = NULL;
2181         cmd->t_data_nents = 0;
2182
2183         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2184         cmd->t_bidi_data_sg = NULL;
2185         cmd->t_bidi_data_nents = 0;
2186 }
2187
2188 /**
2189  * transport_put_cmd - release a reference to a command
2190  * @cmd:       command to release
2191  *
2192  * This routine releases our reference to the command and frees it if possible.
2193  */
2194 static int transport_put_cmd(struct se_cmd *cmd)
2195 {
2196         BUG_ON(!cmd->se_tfo);
2197         /*
2198          * If this cmd has been setup with target_get_sess_cmd(), drop
2199          * the kref and call ->release_cmd() in kref callback.
2200          */
2201         return target_put_sess_cmd(cmd);
2202 }
2203
2204 void *transport_kmap_data_sg(struct se_cmd *cmd)
2205 {
2206         struct scatterlist *sg = cmd->t_data_sg;
2207         struct page **pages;
2208         int i;
2209
2210         /*
2211          * We need to take into account a possible offset here for fabrics like
2212          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2213          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2214          */
2215         if (!cmd->t_data_nents)
2216                 return NULL;
2217
2218         BUG_ON(!sg);
2219         if (cmd->t_data_nents == 1)
2220                 return kmap(sg_page(sg)) + sg->offset;
2221
2222         /* >1 page. use vmap */
2223         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2224         if (!pages)
2225                 return NULL;
2226
2227         /* convert sg[] to pages[] */
2228         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2229                 pages[i] = sg_page(sg);
2230         }
2231
2232         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2233         kfree(pages);
2234         if (!cmd->t_data_vmap)
2235                 return NULL;
2236
2237         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2238 }
2239 EXPORT_SYMBOL(transport_kmap_data_sg);
2240
2241 void transport_kunmap_data_sg(struct se_cmd *cmd)
2242 {
2243         if (!cmd->t_data_nents) {
2244                 return;
2245         } else if (cmd->t_data_nents == 1) {
2246                 kunmap(sg_page(cmd->t_data_sg));
2247                 return;
2248         }
2249
2250         vunmap(cmd->t_data_vmap);
2251         cmd->t_data_vmap = NULL;
2252 }
2253 EXPORT_SYMBOL(transport_kunmap_data_sg);
2254
2255 int
2256 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2257                  bool zero_page)
2258 {
2259         struct scatterlist *sg;
2260         struct page *page;
2261         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2262         unsigned int nent;
2263         int i = 0;
2264
2265         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2266         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2267         if (!sg)
2268                 return -ENOMEM;
2269
2270         sg_init_table(sg, nent);
2271
2272         while (length) {
2273                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2274                 page = alloc_page(GFP_KERNEL | zero_flag);
2275                 if (!page)
2276                         goto out;
2277
2278                 sg_set_page(&sg[i], page, page_len, 0);
2279                 length -= page_len;
2280                 i++;
2281         }
2282         *sgl = sg;
2283         *nents = nent;
2284         return 0;
2285
2286 out:
2287         while (i > 0) {
2288                 i--;
2289                 __free_page(sg_page(&sg[i]));
2290         }
2291         kfree(sg);
2292         return -ENOMEM;
2293 }
2294
2295 /*
2296  * Allocate any required resources to execute the command.  For writes we
2297  * might not have the payload yet, so notify the fabric via a call to
2298  * ->write_pending instead. Otherwise place it on the execution queue.
2299  */
2300 sense_reason_t
2301 transport_generic_new_cmd(struct se_cmd *cmd)
2302 {
2303         int ret = 0;
2304         bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2305
2306         if (cmd->prot_op != TARGET_PROT_NORMAL &&
2307             !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2308                 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2309                                        cmd->prot_length, true);
2310                 if (ret < 0)
2311                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2312         }
2313
2314         /*
2315          * Determine is the TCM fabric module has already allocated physical
2316          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2317          * beforehand.
2318          */
2319         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2320             cmd->data_length) {
2321
2322                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2323                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2324                         u32 bidi_length;
2325
2326                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2327                                 bidi_length = cmd->t_task_nolb *
2328                                               cmd->se_dev->dev_attrib.block_size;
2329                         else
2330                                 bidi_length = cmd->data_length;
2331
2332                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2333                                                &cmd->t_bidi_data_nents,
2334                                                bidi_length, zero_flag);
2335                         if (ret < 0)
2336                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2337                 }
2338
2339                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2340                                        cmd->data_length, zero_flag);
2341                 if (ret < 0)
2342                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2343         } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2344                     cmd->data_length) {
2345                 /*
2346                  * Special case for COMPARE_AND_WRITE with fabrics
2347                  * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2348                  */
2349                 u32 caw_length = cmd->t_task_nolb *
2350                                  cmd->se_dev->dev_attrib.block_size;
2351
2352                 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2353                                        &cmd->t_bidi_data_nents,
2354                                        caw_length, zero_flag);
2355                 if (ret < 0)
2356                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2357         }
2358         /*
2359          * If this command is not a write we can execute it right here,
2360          * for write buffers we need to notify the fabric driver first
2361          * and let it call back once the write buffers are ready.
2362          */
2363         target_add_to_state_list(cmd);
2364         if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2365                 target_execute_cmd(cmd);
2366                 return 0;
2367         }
2368         transport_cmd_check_stop(cmd, false, true);
2369
2370         ret = cmd->se_tfo->write_pending(cmd);
2371         if (ret == -EAGAIN || ret == -ENOMEM)
2372                 goto queue_full;
2373
2374         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2375         WARN_ON(ret);
2376
2377         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2378
2379 queue_full:
2380         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2381         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2382         transport_handle_queue_full(cmd, cmd->se_dev);
2383         return 0;
2384 }
2385 EXPORT_SYMBOL(transport_generic_new_cmd);
2386
2387 static void transport_write_pending_qf(struct se_cmd *cmd)
2388 {
2389         int ret;
2390
2391         ret = cmd->se_tfo->write_pending(cmd);
2392         if (ret == -EAGAIN || ret == -ENOMEM) {
2393                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2394                          cmd);
2395                 transport_handle_queue_full(cmd, cmd->se_dev);
2396         }
2397 }
2398
2399 static bool
2400 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2401                            unsigned long *flags);
2402
2403 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2404 {
2405         unsigned long flags;
2406
2407         spin_lock_irqsave(&cmd->t_state_lock, flags);
2408         __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2409         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2410 }
2411
2412 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2413 {
2414         int ret = 0;
2415         bool aborted = false, tas = false;
2416
2417         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2418                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2419                         target_wait_free_cmd(cmd, &aborted, &tas);
2420
2421                 if (!aborted || tas)
2422                         ret = transport_put_cmd(cmd);
2423         } else {
2424                 if (wait_for_tasks)
2425                         target_wait_free_cmd(cmd, &aborted, &tas);
2426                 /*
2427                  * Handle WRITE failure case where transport_generic_new_cmd()
2428                  * has already added se_cmd to state_list, but fabric has
2429                  * failed command before I/O submission.
2430                  */
2431                 if (cmd->state_active)
2432                         target_remove_from_state_list(cmd);
2433
2434                 if (cmd->se_lun)
2435                         transport_lun_remove_cmd(cmd);
2436
2437                 if (!aborted || tas)
2438                         ret = transport_put_cmd(cmd);
2439         }
2440         /*
2441          * If the task has been internally aborted due to TMR ABORT_TASK
2442          * or LUN_RESET, target_core_tmr.c is responsible for performing
2443          * the remaining calls to target_put_sess_cmd(), and not the
2444          * callers of this function.
2445          */
2446         if (aborted) {
2447                 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2448                 wait_for_completion(&cmd->cmd_wait_comp);
2449                 cmd->se_tfo->release_cmd(cmd);
2450                 ret = 1;
2451         }
2452         return ret;
2453 }
2454 EXPORT_SYMBOL(transport_generic_free_cmd);
2455
2456 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2457  * @se_cmd:     command descriptor to add
2458  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2459  */
2460 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2461 {
2462         struct se_session *se_sess = se_cmd->se_sess;
2463         unsigned long flags;
2464         int ret = 0;
2465
2466         /*
2467          * Add a second kref if the fabric caller is expecting to handle
2468          * fabric acknowledgement that requires two target_put_sess_cmd()
2469          * invocations before se_cmd descriptor release.
2470          */
2471         if (ack_kref)
2472                 kref_get(&se_cmd->cmd_kref);
2473
2474         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2475         if (se_sess->sess_tearing_down) {
2476                 ret = -ESHUTDOWN;
2477                 goto out;
2478         }
2479         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2480 out:
2481         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2482
2483         if (ret && ack_kref)
2484                 target_put_sess_cmd(se_cmd);
2485
2486         return ret;
2487 }
2488 EXPORT_SYMBOL(target_get_sess_cmd);
2489
2490 static void target_free_cmd_mem(struct se_cmd *cmd)
2491 {
2492         transport_free_pages(cmd);
2493
2494         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2495                 core_tmr_release_req(cmd->se_tmr_req);
2496         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2497                 kfree(cmd->t_task_cdb);
2498 }
2499
2500 static void target_release_cmd_kref(struct kref *kref)
2501 {
2502         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2503         struct se_session *se_sess = se_cmd->se_sess;
2504         unsigned long flags;
2505         bool fabric_stop;
2506
2507         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2508         if (list_empty(&se_cmd->se_cmd_list)) {
2509                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2510                 target_free_cmd_mem(se_cmd);
2511                 se_cmd->se_tfo->release_cmd(se_cmd);
2512                 return;
2513         }
2514
2515         spin_lock(&se_cmd->t_state_lock);
2516         fabric_stop = (se_cmd->transport_state & CMD_T_FABRIC_STOP);
2517         spin_unlock(&se_cmd->t_state_lock);
2518
2519         if (se_cmd->cmd_wait_set || fabric_stop) {
2520                 list_del_init(&se_cmd->se_cmd_list);
2521                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2522                 target_free_cmd_mem(se_cmd);
2523                 complete(&se_cmd->cmd_wait_comp);
2524                 return;
2525         }
2526         list_del_init(&se_cmd->se_cmd_list);
2527         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2528
2529         target_free_cmd_mem(se_cmd);
2530         se_cmd->se_tfo->release_cmd(se_cmd);
2531 }
2532
2533 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2534  * @se_cmd:     command descriptor to drop
2535  */
2536 int target_put_sess_cmd(struct se_cmd *se_cmd)
2537 {
2538         struct se_session *se_sess = se_cmd->se_sess;
2539
2540         if (!se_sess) {
2541                 target_free_cmd_mem(se_cmd);
2542                 se_cmd->se_tfo->release_cmd(se_cmd);
2543                 return 1;
2544         }
2545         return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2546 }
2547 EXPORT_SYMBOL(target_put_sess_cmd);
2548
2549 /* target_sess_cmd_list_set_waiting - Flag all commands in
2550  *         sess_cmd_list to complete cmd_wait_comp.  Set
2551  *         sess_tearing_down so no more commands are queued.
2552  * @se_sess:    session to flag
2553  */
2554 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2555 {
2556         struct se_cmd *se_cmd;
2557         unsigned long flags;
2558         int rc;
2559
2560         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2561         if (se_sess->sess_tearing_down) {
2562                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2563                 return;
2564         }
2565         se_sess->sess_tearing_down = 1;
2566         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2567
2568         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list) {
2569                 rc = kref_get_unless_zero(&se_cmd->cmd_kref);
2570                 if (rc) {
2571                         se_cmd->cmd_wait_set = 1;
2572                         spin_lock(&se_cmd->t_state_lock);
2573                         se_cmd->transport_state |= CMD_T_FABRIC_STOP;
2574                         spin_unlock(&se_cmd->t_state_lock);
2575                 }
2576         }
2577
2578         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2579 }
2580 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2581
2582 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2583  * @se_sess:    session to wait for active I/O
2584  */
2585 void target_wait_for_sess_cmds(struct se_session *se_sess)
2586 {
2587         struct se_cmd *se_cmd, *tmp_cmd;
2588         unsigned long flags;
2589         bool tas;
2590
2591         list_for_each_entry_safe(se_cmd, tmp_cmd,
2592                                 &se_sess->sess_wait_list, se_cmd_list) {
2593                 list_del_init(&se_cmd->se_cmd_list);
2594
2595                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2596                         " %d\n", se_cmd, se_cmd->t_state,
2597                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2598
2599                 spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2600                 tas = (se_cmd->transport_state & CMD_T_TAS);
2601                 spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2602
2603                 if (!target_put_sess_cmd(se_cmd)) {
2604                         if (tas)
2605                                 target_put_sess_cmd(se_cmd);
2606                 }
2607
2608                 wait_for_completion(&se_cmd->cmd_wait_comp);
2609                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2610                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2611                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2612
2613                 se_cmd->se_tfo->release_cmd(se_cmd);
2614         }
2615
2616         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2617         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2618         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2619
2620 }
2621 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2622
2623 void transport_clear_lun_ref(struct se_lun *lun)
2624 {
2625         percpu_ref_kill(&lun->lun_ref);
2626         wait_for_completion(&lun->lun_ref_comp);
2627 }
2628
2629 static bool
2630 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2631                            bool *aborted, bool *tas, unsigned long *flags)
2632         __releases(&cmd->t_state_lock)
2633         __acquires(&cmd->t_state_lock)
2634 {
2635
2636         assert_spin_locked(&cmd->t_state_lock);
2637         WARN_ON_ONCE(!irqs_disabled());
2638
2639         if (fabric_stop)
2640                 cmd->transport_state |= CMD_T_FABRIC_STOP;
2641
2642         if (cmd->transport_state & CMD_T_ABORTED)
2643                 *aborted = true;
2644
2645         if (cmd->transport_state & CMD_T_TAS)
2646                 *tas = true;
2647
2648         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2649             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2650                 return false;
2651
2652         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2653             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2654                 return false;
2655
2656         if (!(cmd->transport_state & CMD_T_ACTIVE))
2657                 return false;
2658
2659         if (fabric_stop && *aborted)
2660                 return false;
2661
2662         cmd->transport_state |= CMD_T_STOP;
2663
2664         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08llx i_state: %d,"
2665                  " t_state: %d, CMD_T_STOP\n", cmd, cmd->tag,
2666                  cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2667
2668         spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2669
2670         wait_for_completion(&cmd->t_transport_stop_comp);
2671
2672         spin_lock_irqsave(&cmd->t_state_lock, *flags);
2673         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2674
2675         pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
2676                  "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
2677
2678         return true;
2679 }
2680
2681 /**
2682  * transport_wait_for_tasks - wait for completion to occur
2683  * @cmd:        command to wait
2684  *
2685  * Called from frontend fabric context to wait for storage engine
2686  * to pause and/or release frontend generated struct se_cmd.
2687  */
2688 bool transport_wait_for_tasks(struct se_cmd *cmd)
2689 {
2690         unsigned long flags;
2691         bool ret, aborted = false, tas = false;
2692
2693         spin_lock_irqsave(&cmd->t_state_lock, flags);
2694         ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
2695         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2696
2697         return ret;
2698 }
2699 EXPORT_SYMBOL(transport_wait_for_tasks);
2700
2701 struct sense_info {
2702         u8 key;
2703         u8 asc;
2704         u8 ascq;
2705         bool add_sector_info;
2706 };
2707
2708 static const struct sense_info sense_info_table[] = {
2709         [TCM_NO_SENSE] = {
2710                 .key = NOT_READY
2711         },
2712         [TCM_NON_EXISTENT_LUN] = {
2713                 .key = ILLEGAL_REQUEST,
2714                 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
2715         },
2716         [TCM_UNSUPPORTED_SCSI_OPCODE] = {
2717                 .key = ILLEGAL_REQUEST,
2718                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2719         },
2720         [TCM_SECTOR_COUNT_TOO_MANY] = {
2721                 .key = ILLEGAL_REQUEST,
2722                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2723         },
2724         [TCM_UNKNOWN_MODE_PAGE] = {
2725                 .key = ILLEGAL_REQUEST,
2726                 .asc = 0x24, /* INVALID FIELD IN CDB */
2727         },
2728         [TCM_CHECK_CONDITION_ABORT_CMD] = {
2729                 .key = ABORTED_COMMAND,
2730                 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
2731                 .ascq = 0x03,
2732         },
2733         [TCM_INCORRECT_AMOUNT_OF_DATA] = {
2734                 .key = ABORTED_COMMAND,
2735                 .asc = 0x0c, /* WRITE ERROR */
2736                 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
2737         },
2738         [TCM_INVALID_CDB_FIELD] = {
2739                 .key = ILLEGAL_REQUEST,
2740                 .asc = 0x24, /* INVALID FIELD IN CDB */
2741         },
2742         [TCM_INVALID_PARAMETER_LIST] = {
2743                 .key = ILLEGAL_REQUEST,
2744                 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
2745         },
2746         [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
2747                 .key = ILLEGAL_REQUEST,
2748                 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
2749         },
2750         [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
2751                 .key = ILLEGAL_REQUEST,
2752                 .asc = 0x0c, /* WRITE ERROR */
2753                 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
2754         },
2755         [TCM_SERVICE_CRC_ERROR] = {
2756                 .key = ABORTED_COMMAND,
2757                 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
2758                 .ascq = 0x05, /* N/A */
2759         },
2760         [TCM_SNACK_REJECTED] = {
2761                 .key = ABORTED_COMMAND,
2762                 .asc = 0x11, /* READ ERROR */
2763                 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
2764         },
2765         [TCM_WRITE_PROTECTED] = {
2766                 .key = DATA_PROTECT,
2767                 .asc = 0x27, /* WRITE PROTECTED */
2768         },
2769         [TCM_ADDRESS_OUT_OF_RANGE] = {
2770                 .key = ILLEGAL_REQUEST,
2771                 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2772         },
2773         [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
2774                 .key = UNIT_ATTENTION,
2775         },
2776         [TCM_CHECK_CONDITION_NOT_READY] = {
2777                 .key = NOT_READY,
2778         },
2779         [TCM_MISCOMPARE_VERIFY] = {
2780                 .key = MISCOMPARE,
2781                 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
2782                 .ascq = 0x00,
2783         },
2784         [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
2785                 .key = ABORTED_COMMAND,
2786                 .asc = 0x10,
2787                 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
2788                 .add_sector_info = true,
2789         },
2790         [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
2791                 .key = ABORTED_COMMAND,
2792                 .asc = 0x10,
2793                 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2794                 .add_sector_info = true,
2795         },
2796         [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
2797                 .key = ABORTED_COMMAND,
2798                 .asc = 0x10,
2799                 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2800                 .add_sector_info = true,
2801         },
2802         [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
2803                 /*
2804                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2805                  * Solaris initiators.  Returning NOT READY instead means the
2806                  * operations will be retried a finite number of times and we
2807                  * can survive intermittent errors.
2808                  */
2809                 .key = NOT_READY,
2810                 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
2811         },
2812 };
2813
2814 static int translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
2815 {
2816         const struct sense_info *si;
2817         u8 *buffer = cmd->sense_buffer;
2818         int r = (__force int)reason;
2819         u8 asc, ascq;
2820         bool desc_format = target_sense_desc_format(cmd->se_dev);
2821
2822         if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
2823                 si = &sense_info_table[r];
2824         else
2825                 si = &sense_info_table[(__force int)
2826                                        TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
2827
2828         if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
2829                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2830                 WARN_ON_ONCE(asc == 0);
2831         } else if (si->asc == 0) {
2832                 WARN_ON_ONCE(cmd->scsi_asc == 0);
2833                 asc = cmd->scsi_asc;
2834                 ascq = cmd->scsi_ascq;
2835         } else {
2836                 asc = si->asc;
2837                 ascq = si->ascq;
2838         }
2839
2840         scsi_build_sense_buffer(desc_format, buffer, si->key, asc, ascq);
2841         if (si->add_sector_info)
2842                 return scsi_set_sense_information(buffer,
2843                                                   cmd->scsi_sense_length,
2844                                                   cmd->bad_sector);
2845
2846         return 0;
2847 }
2848
2849 int
2850 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2851                 sense_reason_t reason, int from_transport)
2852 {
2853         unsigned long flags;
2854
2855         spin_lock_irqsave(&cmd->t_state_lock, flags);
2856         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2857                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2858                 return 0;
2859         }
2860         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2861         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2862
2863         if (!from_transport) {
2864                 int rc;
2865
2866                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2867                 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2868                 cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2869                 rc = translate_sense_reason(cmd, reason);
2870                 if (rc)
2871                         return rc;
2872         }
2873
2874         trace_target_cmd_complete(cmd);
2875         return cmd->se_tfo->queue_status(cmd);
2876 }
2877 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2878
2879 static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2880         __releases(&cmd->t_state_lock)
2881         __acquires(&cmd->t_state_lock)
2882 {
2883         assert_spin_locked(&cmd->t_state_lock);
2884         WARN_ON_ONCE(!irqs_disabled());
2885
2886         if (!(cmd->transport_state & CMD_T_ABORTED))
2887                 return 0;
2888         /*
2889          * If cmd has been aborted but either no status is to be sent or it has
2890          * already been sent, just return
2891          */
2892         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
2893                 if (send_status)
2894                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2895                 return 1;
2896         }
2897
2898         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
2899                 " 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);
2900
2901         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2902         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2903         trace_target_cmd_complete(cmd);
2904
2905         spin_unlock_irq(&cmd->t_state_lock);
2906         cmd->se_tfo->queue_status(cmd);
2907         spin_lock_irq(&cmd->t_state_lock);
2908
2909         return 1;
2910 }
2911
2912 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2913 {
2914         int ret;
2915
2916         spin_lock_irq(&cmd->t_state_lock);
2917         ret = __transport_check_aborted_status(cmd, send_status);
2918         spin_unlock_irq(&cmd->t_state_lock);
2919
2920         return ret;
2921 }
2922 EXPORT_SYMBOL(transport_check_aborted_status);
2923
2924 void transport_send_task_abort(struct se_cmd *cmd)
2925 {
2926         unsigned long flags;
2927
2928         spin_lock_irqsave(&cmd->t_state_lock, flags);
2929         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2930                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2931                 return;
2932         }
2933         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2934
2935         /*
2936          * If there are still expected incoming fabric WRITEs, we wait
2937          * until until they have completed before sending a TASK_ABORTED
2938          * response.  This response with TASK_ABORTED status will be
2939          * queued back to fabric module by transport_check_aborted_status().
2940          */
2941         if (cmd->data_direction == DMA_TO_DEVICE) {
2942                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2943                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2944                         if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) {
2945                                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2946                                 goto send_abort;
2947                         }
2948                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2949                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2950                         return;
2951                 }
2952         }
2953 send_abort:
2954         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2955
2956         transport_lun_remove_cmd(cmd);
2957
2958         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
2959                  cmd->t_task_cdb[0], cmd->tag);
2960
2961         trace_target_cmd_complete(cmd);
2962         cmd->se_tfo->queue_status(cmd);
2963 }
2964
2965 static void target_tmr_work(struct work_struct *work)
2966 {
2967         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2968         struct se_device *dev = cmd->se_dev;
2969         struct se_tmr_req *tmr = cmd->se_tmr_req;
2970         unsigned long flags;
2971         int ret;
2972
2973         spin_lock_irqsave(&cmd->t_state_lock, flags);
2974         if (cmd->transport_state & CMD_T_ABORTED) {
2975                 tmr->response = TMR_FUNCTION_REJECTED;
2976                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2977                 goto check_stop;
2978         }
2979         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2980
2981         switch (tmr->function) {
2982         case TMR_ABORT_TASK:
2983                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
2984                 break;
2985         case TMR_ABORT_TASK_SET:
2986         case TMR_CLEAR_ACA:
2987         case TMR_CLEAR_TASK_SET:
2988                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
2989                 break;
2990         case TMR_LUN_RESET:
2991                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
2992                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
2993                                          TMR_FUNCTION_REJECTED;
2994                 if (tmr->response == TMR_FUNCTION_COMPLETE) {
2995                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
2996                                                cmd->orig_fe_lun, 0x29,
2997                                                ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
2998                 }
2999                 break;
3000         case TMR_TARGET_WARM_RESET:
3001                 tmr->response = TMR_FUNCTION_REJECTED;
3002                 break;
3003         case TMR_TARGET_COLD_RESET:
3004                 tmr->response = TMR_FUNCTION_REJECTED;
3005                 break;
3006         default:
3007                 pr_err("Uknown TMR function: 0x%02x.\n",
3008                                 tmr->function);
3009                 tmr->response = TMR_FUNCTION_REJECTED;
3010                 break;
3011         }
3012
3013         spin_lock_irqsave(&cmd->t_state_lock, flags);
3014         if (cmd->transport_state & CMD_T_ABORTED) {
3015                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3016                 goto check_stop;
3017         }
3018         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3019         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3020
3021         cmd->se_tfo->queue_tm_rsp(cmd);
3022
3023 check_stop:
3024         transport_cmd_check_stop_to_fabric(cmd);
3025 }
3026
3027 int transport_generic_handle_tmr(
3028         struct se_cmd *cmd)
3029 {
3030         unsigned long flags;
3031
3032         spin_lock_irqsave(&cmd->t_state_lock, flags);
3033         cmd->transport_state |= CMD_T_ACTIVE;
3034         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3035
3036         INIT_WORK(&cmd->work, target_tmr_work);
3037         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3038         return 0;
3039 }
3040 EXPORT_SYMBOL(transport_generic_handle_tmr);
3041
3042 bool
3043 target_check_wce(struct se_device *dev)
3044 {
3045         bool wce = false;
3046
3047         if (dev->transport->get_write_cache)
3048                 wce = dev->transport->get_write_cache(dev);
3049         else if (dev->dev_attrib.emulate_write_cache > 0)
3050                 wce = true;
3051
3052         return wce;
3053 }
3054
3055 bool
3056 target_check_fua(struct se_device *dev)
3057 {
3058         return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3059 }