drivers/target/target_core_transport.c

   1 /*******************************************************************************
   2  * Filename:  target_core_transport.c
   3  *
   4  * This file contains the Generic Target Engine Core.
   5  *
   6  * (c) Copyright 2002-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/net.h>
  27 #include <linux/delay.h>
  28 #include <linux/string.h>
  29 #include <linux/timer.h>
  30 #include <linux/slab.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/kthread.h>
  33 #include <linux/in.h>
  34 #include <linux/cdrom.h>
  35 #include <linux/module.h>
  36 #include <linux/ratelimit.h>
  37 #include <asm/unaligned.h>
  38 #include <net/sock.h>
  39 #include <net/tcp.h>
  40 #include <scsi/scsi.h>
  41 #include <scsi/scsi_cmnd.h>
  42 #include <scsi/scsi_tcq.h>
  43
  44 #include <target/target_core_base.h>
  45 #include <target/target_core_backend.h>
  46 #include <target/target_core_fabric.h>
  47
  48 #include "target_core_internal.h"
  49 #include "target_core_alua.h"
  50 #include "target_core_pr.h"
  51 #include "target_core_ua.h"
  52
  53 #define CREATE_TRACE_POINTS
  54 #include <trace/events/target.h>
  55
  56 static struct workqueue_struct *target_completion_wq;
  57 static struct kmem_cache *se_sess_cache;
  58 struct kmem_cache *se_ua_cache;
  59 struct kmem_cache *t10_pr_reg_cache;
  60 struct kmem_cache *t10_alua_lu_gp_cache;
  61 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  62 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  63 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
  64 struct kmem_cache *t10_alua_lba_map_cache;
  65 struct kmem_cache *t10_alua_lba_map_mem_cache;
  66
  67 static void transport_complete_task_attr(struct se_cmd *cmd);
  68 static void transport_handle_queue_full(struct se_cmd *cmd,
  69                 struct se_device *dev);
  70 static int transport_put_cmd(struct se_cmd *cmd);
  71 static void target_complete_ok_work(struct work_struct *work);
  72
  73 int init_se_kmem_caches(void)
  74 {
  75         se_sess_cache = kmem_cache_create("se_sess_cache",
  76                         sizeof(struct se_session), __alignof__(struct se_session),
  77                         0, NULL);
  78         if (!se_sess_cache) {
  79                 pr_err("kmem_cache_create() for struct se_session"
  80                                 " failed\n");
  81                 goto out;
  82         }
  83         se_ua_cache = kmem_cache_create("se_ua_cache",
  84                         sizeof(struct se_ua), __alignof__(struct se_ua),
  85                         0, NULL);
  86         if (!se_ua_cache) {
  87                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  88                 goto out_free_sess_cache;
  89         }
  90         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  91                         sizeof(struct t10_pr_registration),
  92                         __alignof__(struct t10_pr_registration), 0, NULL);
  93         if (!t10_pr_reg_cache) {
  94                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  95                                 " failed\n");
  96                 goto out_free_ua_cache;
  97         }
  98         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
  99                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
 100                         0, NULL);
 101         if (!t10_alua_lu_gp_cache) {
 102                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 103                                 " failed\n");
 104                 goto out_free_pr_reg_cache;
 105         }
 106         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 107                         sizeof(struct t10_alua_lu_gp_member),
 108                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 109         if (!t10_alua_lu_gp_mem_cache) {
 110                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 111                                 "cache failed\n");
 112                 goto out_free_lu_gp_cache;
 113         }
 114         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 115                         sizeof(struct t10_alua_tg_pt_gp),
 116                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 117         if (!t10_alua_tg_pt_gp_cache) {
 118                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 119                                 "cache failed\n");
 120                 goto out_free_lu_gp_mem_cache;
 121         }
 122         t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
 123                         "t10_alua_tg_pt_gp_mem_cache",
 124                         sizeof(struct t10_alua_tg_pt_gp_member),
 125                         __alignof__(struct t10_alua_tg_pt_gp_member),
 126                         0, NULL);
 127         if (!t10_alua_tg_pt_gp_mem_cache) {
 128                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 129                                 "mem_t failed\n");
 130                 goto out_free_tg_pt_gp_cache;
 131         }
 132         t10_alua_lba_map_cache = kmem_cache_create(
 133                         "t10_alua_lba_map_cache",
 134                         sizeof(struct t10_alua_lba_map),
 135                         __alignof__(struct t10_alua_lba_map), 0, NULL);
 136         if (!t10_alua_lba_map_cache) {
 137                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
 138                                 "cache failed\n");
 139                 goto out_free_tg_pt_gp_mem_cache;
 140         }
 141         t10_alua_lba_map_mem_cache = kmem_cache_create(
 142                         "t10_alua_lba_map_mem_cache",
 143                         sizeof(struct t10_alua_lba_map_member),
 144                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
 145         if (!t10_alua_lba_map_mem_cache) {
 146                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
 147                                 "cache failed\n");
 148                 goto out_free_lba_map_cache;
 149         }
 150
 151         target_completion_wq = alloc_workqueue("target_completion",
 152                                                WQ_MEM_RECLAIM, 0);
 153         if (!target_completion_wq)
 154                 goto out_free_lba_map_mem_cache;
 155
 156         return 0;
 157
 158 out_free_lba_map_mem_cache:
 159         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 160 out_free_lba_map_cache:
 161         kmem_cache_destroy(t10_alua_lba_map_cache);
 162 out_free_tg_pt_gp_mem_cache:
 163         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 164 out_free_tg_pt_gp_cache:
 165         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 166 out_free_lu_gp_mem_cache:
 167         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 168 out_free_lu_gp_cache:
 169         kmem_cache_destroy(t10_alua_lu_gp_cache);
 170 out_free_pr_reg_cache:
 171         kmem_cache_destroy(t10_pr_reg_cache);
 172 out_free_ua_cache:
 173         kmem_cache_destroy(se_ua_cache);
 174 out_free_sess_cache:
 175         kmem_cache_destroy(se_sess_cache);
 176 out:
 177         return -ENOMEM;
 178 }
 179
 180 void release_se_kmem_caches(void)
 181 {
 182         destroy_workqueue(target_completion_wq);
 183         kmem_cache_destroy(se_sess_cache);
 184         kmem_cache_destroy(se_ua_cache);
 185         kmem_cache_destroy(t10_pr_reg_cache);
 186         kmem_cache_destroy(t10_alua_lu_gp_cache);
 187         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 188         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 189         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 190         kmem_cache_destroy(t10_alua_lba_map_cache);
 191         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 192 }
 193
 194 /* This code ensures unique mib indexes are handed out. */
 195 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 196 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 197
 198 /*
 199  * Allocate a new row index for the entry type specified
 200  */
 201 u32 scsi_get_new_index(scsi_index_t type)
 202 {
 203         u32 new_index;
 204
 205         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 206
 207         spin_lock(&scsi_mib_index_lock);
 208         new_index = ++scsi_mib_index[type];
 209         spin_unlock(&scsi_mib_index_lock);
 210
 211         return new_index;
 212 }
 213
 214 void transport_subsystem_check_init(void)
 215 {
 216         int ret;
 217         static int sub_api_initialized;
 218
 219         if (sub_api_initialized)
 220                 return;
 221
 222         ret = request_module("target_core_iblock");
 223         if (ret != 0)
 224                 pr_err("Unable to load target_core_iblock\n");
 225
 226         ret = request_module("target_core_file");
 227         if (ret != 0)
 228                 pr_err("Unable to load target_core_file\n");
 229
 230         ret = request_module("target_core_pscsi");
 231         if (ret != 0)
 232                 pr_err("Unable to load target_core_pscsi\n");
 233
 234         ret = request_module("target_core_user");
 235         if (ret != 0)
 236                 pr_err("Unable to load target_core_user\n");
 237
 238         sub_api_initialized = 1;
 239 }
 240
 241 struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
 242 {
 243         struct se_session *se_sess;
 244
 245         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 246         if (!se_sess) {
 247                 pr_err("Unable to allocate struct se_session from"
 248                                 " se_sess_cache\n");
 249                 return ERR_PTR(-ENOMEM);
 250         }
 251         INIT_LIST_HEAD(&se_sess->sess_list);
 252         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 253         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 254         INIT_LIST_HEAD(&se_sess->sess_wait_list);
 255         spin_lock_init(&se_sess->sess_cmd_lock);
 256         kref_init(&se_sess->sess_kref);
 257         se_sess->sup_prot_ops = sup_prot_ops;
 258
 259         return se_sess;
 260 }
 261 EXPORT_SYMBOL(transport_init_session);
 262
 263 int transport_alloc_session_tags(struct se_session *se_sess,
 264                                  unsigned int tag_num, unsigned int tag_size)
 265 {
 266         int rc;
 267
 268         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
 269                                         GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
 270         if (!se_sess->sess_cmd_map) {
 271                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
 272                 if (!se_sess->sess_cmd_map) {
 273                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 274                         return -ENOMEM;
 275                 }
 276         }
 277
 278         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
 279         if (rc < 0) {
 280                 pr_err("Unable to init se_sess->sess_tag_pool,"
 281                         " tag_num: %u\n", tag_num);
 282                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 283                         vfree(se_sess->sess_cmd_map);
 284                 else
 285                         kfree(se_sess->sess_cmd_map);
 286                 se_sess->sess_cmd_map = NULL;
 287                 return -ENOMEM;
 288         }
 289
 290         return 0;
 291 }
 292 EXPORT_SYMBOL(transport_alloc_session_tags);
 293
 294 struct se_session *transport_init_session_tags(unsigned int tag_num,
 295                                                unsigned int tag_size,
 296                                                enum target_prot_op sup_prot_ops)
 297 {
 298         struct se_session *se_sess;
 299         int rc;
 300
 301         se_sess = transport_init_session(sup_prot_ops);
 302         if (IS_ERR(se_sess))
 303                 return se_sess;
 304
 305         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 306         if (rc < 0) {
 307                 transport_free_session(se_sess);
 308                 return ERR_PTR(-ENOMEM);
 309         }
 310
 311         return se_sess;
 312 }
 313 EXPORT_SYMBOL(transport_init_session_tags);
 314
 315 /*
 316  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 317  */
 318 void __transport_register_session(
 319         struct se_portal_group *se_tpg,
 320         struct se_node_acl *se_nacl,
 321         struct se_session *se_sess,
 322         void *fabric_sess_ptr)
 323 {
 324         const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
 325         unsigned char buf[PR_REG_ISID_LEN];
 326
 327         se_sess->se_tpg = se_tpg;
 328         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 329         /*
 330          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 331          *
 332          * Only set for struct se_session's that will actually be moving I/O.
 333          * eg: *NOT* discovery sessions.
 334          */
 335         if (se_nacl) {
 336                 /*
 337                  *
 338                  * Determine if fabric allows for T10-PI feature bits exposed to
 339                  * initiators for device backends with !dev->dev_attrib.pi_prot_type.
 340                  *
 341                  * If so, then always save prot_type on a per se_node_acl node
 342                  * basis and re-instate the previous sess_prot_type to avoid
 343                  * disabling PI from below any previously initiator side
 344                  * registered LUNs.
 345                  */
 346                 if (se_nacl->saved_prot_type)
 347                         se_sess->sess_prot_type = se_nacl->saved_prot_type;
 348                 else if (tfo->tpg_check_prot_fabric_only)
 349                         se_sess->sess_prot_type = se_nacl->saved_prot_type =
 350                                         tfo->tpg_check_prot_fabric_only(se_tpg);
 351                 /*
 352                  * If the fabric module supports an ISID based TransportID,
 353                  * save this value in binary from the fabric I_T Nexus now.
 354                  */
 355                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 356                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 357                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 358                                         &buf[0], PR_REG_ISID_LEN);
 359                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 360                 }
 361                 kref_get(&se_nacl->acl_kref);
 362
 363                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 364                 /*
 365                  * The se_nacl->nacl_sess pointer will be set to the
 366                  * last active I_T Nexus for each struct se_node_acl.
 367                  */
 368                 se_nacl->nacl_sess = se_sess;
 369
 370                 list_add_tail(&se_sess->sess_acl_list,
 371                               &se_nacl->acl_sess_list);
 372                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 373         }
 374         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 375
 376         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 377                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 378 }
 379 EXPORT_SYMBOL(__transport_register_session);
 380
 381 void transport_register_session(
 382         struct se_portal_group *se_tpg,
 383         struct se_node_acl *se_nacl,
 384         struct se_session *se_sess,
 385         void *fabric_sess_ptr)
 386 {
 387         unsigned long flags;
 388
 389         spin_lock_irqsave(&se_tpg->session_lock, flags);
 390         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 391         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 392 }
 393 EXPORT_SYMBOL(transport_register_session);
 394
 395 static void target_release_session(struct kref *kref)
 396 {
 397         struct se_session *se_sess = container_of(kref,
 398                         struct se_session, sess_kref);
 399         struct se_portal_group *se_tpg = se_sess->se_tpg;
 400
 401         se_tpg->se_tpg_tfo->close_session(se_sess);
 402 }
 403
 404 void target_get_session(struct se_session *se_sess)
 405 {
 406         kref_get(&se_sess->sess_kref);
 407 }
 408 EXPORT_SYMBOL(target_get_session);
 409
 410 void target_put_session(struct se_session *se_sess)
 411 {
 412         kref_put(&se_sess->sess_kref, target_release_session);
 413 }
 414 EXPORT_SYMBOL(target_put_session);
 415
 416 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
 417 {
 418         struct se_session *se_sess;
 419         ssize_t len = 0;
 420
 421         spin_lock_bh(&se_tpg->session_lock);
 422         list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
 423                 if (!se_sess->se_node_acl)
 424                         continue;
 425                 if (!se_sess->se_node_acl->dynamic_node_acl)
 426                         continue;
 427                 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
 428                         break;
 429
 430                 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
 431                                 se_sess->se_node_acl->initiatorname);
 432                 len += 1; /* Include NULL terminator */
 433         }
 434         spin_unlock_bh(&se_tpg->session_lock);
 435
 436         return len;
 437 }
 438 EXPORT_SYMBOL(target_show_dynamic_sessions);
 439
 440 static void target_complete_nacl(struct kref *kref)
 441 {
 442         struct se_node_acl *nacl = container_of(kref,
 443                                 struct se_node_acl, acl_kref);
 444
 445         complete(&nacl->acl_free_comp);
 446 }
 447
 448 void target_put_nacl(struct se_node_acl *nacl)
 449 {
 450         kref_put(&nacl->acl_kref, target_complete_nacl);
 451 }
 452
 453 void transport_deregister_session_configfs(struct se_session *se_sess)
 454 {
 455         struct se_node_acl *se_nacl;
 456         unsigned long flags;
 457         /*
 458          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 459          */
 460         se_nacl = se_sess->se_node_acl;
 461         if (se_nacl) {
 462                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 463                 if (se_nacl->acl_stop == 0)
 464                         list_del(&se_sess->sess_acl_list);
 465                 /*
 466                  * If the session list is empty, then clear the pointer.
 467                  * Otherwise, set the struct se_session pointer from the tail
 468                  * element of the per struct se_node_acl active session list.
 469                  */
 470                 if (list_empty(&se_nacl->acl_sess_list))
 471                         se_nacl->nacl_sess = NULL;
 472                 else {
 473                         se_nacl->nacl_sess = container_of(
 474                                         se_nacl->acl_sess_list.prev,
 475                                         struct se_session, sess_acl_list);
 476                 }
 477                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 478         }
 479 }
 480 EXPORT_SYMBOL(transport_deregister_session_configfs);
 481
 482 void transport_free_session(struct se_session *se_sess)
 483 {
 484         if (se_sess->sess_cmd_map) {
 485                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 486                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 487                         vfree(se_sess->sess_cmd_map);
 488                 else
 489                         kfree(se_sess->sess_cmd_map);
 490         }
 491         kmem_cache_free(se_sess_cache, se_sess);
 492 }
 493 EXPORT_SYMBOL(transport_free_session);
 494
 495 void transport_deregister_session(struct se_session *se_sess)
 496 {
 497         struct se_portal_group *se_tpg = se_sess->se_tpg;
 498         const struct target_core_fabric_ops *se_tfo;
 499         struct se_node_acl *se_nacl;
 500         unsigned long flags;
 501         bool comp_nacl = true, drop_nacl = false;
 502
 503         if (!se_tpg) {
 504                 transport_free_session(se_sess);
 505                 return;
 506         }
 507         se_tfo = se_tpg->se_tpg_tfo;
 508
 509         spin_lock_irqsave(&se_tpg->session_lock, flags);
 510         list_del(&se_sess->sess_list);
 511         se_sess->se_tpg = NULL;
 512         se_sess->fabric_sess_ptr = NULL;
 513         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 514
 515         /*
 516          * Determine if we need to do extra work for this initiator node's
 517          * struct se_node_acl if it had been previously dynamically generated.
 518          */
 519         se_nacl = se_sess->se_node_acl;
 520
 521         mutex_lock(&se_tpg->acl_node_mutex);
 522         if (se_nacl && se_nacl->dynamic_node_acl) {
 523                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 524                         list_del(&se_nacl->acl_list);
 525                         se_tpg->num_node_acls--;
 526                         drop_nacl = true;
 527                 }
 528         }
 529         mutex_unlock(&se_tpg->acl_node_mutex);
 530
 531         if (drop_nacl) {
 532                 core_tpg_wait_for_nacl_pr_ref(se_nacl);
 533                 core_free_device_list_for_node(se_nacl, se_tpg);
 534                 kfree(se_nacl);
 535                 comp_nacl = false;
 536         }
 537         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 538                 se_tpg->se_tpg_tfo->get_fabric_name());
 539         /*
 540          * If last kref is dropping now for an explicit NodeACL, awake sleeping
 541          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 542          * removal context.
 543          */
 544         if (se_nacl && comp_nacl)
 545                 target_put_nacl(se_nacl);
 546
 547         transport_free_session(se_sess);
 548 }
 549 EXPORT_SYMBOL(transport_deregister_session);
 550
 551 /*
 552  * Called with cmd->t_state_lock held.
 553  */
 554 static void target_remove_from_state_list(struct se_cmd *cmd)
 555 {
 556         struct se_device *dev = cmd->se_dev;
 557         unsigned long flags;
 558
 559         if (!dev)
 560                 return;
 561
 562         if (cmd->transport_state & CMD_T_BUSY)
 563                 return;
 564
 565         spin_lock_irqsave(&dev->execute_task_lock, flags);
 566         if (cmd->state_active) {
 567                 list_del(&cmd->state_list);
 568                 cmd->state_active = false;
 569         }
 570         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 571 }
 572
 573 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 574                                     bool write_pending)
 575 {
 576         unsigned long flags;
 577
 578         spin_lock_irqsave(&cmd->t_state_lock, flags);
 579         if (write_pending)
 580                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 581
 582         if (remove_from_lists) {
 583                 target_remove_from_state_list(cmd);
 584
 585                 /*
 586                  * Clear struct se_cmd->se_lun before the handoff to FE.
 587                  */
 588                 cmd->se_lun = NULL;
 589         }
 590
 591         /*
 592          * Determine if frontend context caller is requesting the stopping of
 593          * this command for frontend exceptions.
 594          */
 595         if (cmd->transport_state & CMD_T_STOP) {
 596                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
 597                         __func__, __LINE__, cmd->tag);
 598
 599                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 600
 601                 complete_all(&cmd->t_transport_stop_comp);
 602                 return 1;
 603         }
 604
 605         cmd->transport_state &= ~CMD_T_ACTIVE;
 606         if (remove_from_lists) {
 607                 /*
 608                  * Some fabric modules like tcm_loop can release
 609                  * their internally allocated I/O reference now and
 610                  * struct se_cmd now.
 611                  *
 612                  * Fabric modules are expected to return '1' here if the
 613                  * se_cmd being passed is released at this point,
 614                  * or zero if not being released.
 615                  */
 616                 if (cmd->se_tfo->check_stop_free != NULL) {
 617                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 618                         return cmd->se_tfo->check_stop_free(cmd);
 619                 }
 620         }
 621
 622         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 623         return 0;
 624 }
 625
 626 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 627 {
 628         return transport_cmd_check_stop(cmd, true, false);
 629 }
 630
 631 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 632 {
 633         struct se_lun *lun = cmd->se_lun;
 634
 635         if (!lun)
 636                 return;
 637
 638         if (cmpxchg(&cmd->lun_ref_active, true, false))
 639                 percpu_ref_put(&lun->lun_ref);
 640 }
 641
 642 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 643 {
 644         if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
 645                 transport_lun_remove_cmd(cmd);
 646         /*
 647          * Allow the fabric driver to unmap any resources before
 648          * releasing the descriptor via TFO->release_cmd()
 649          */
 650         if (remove)
 651                 cmd->se_tfo->aborted_task(cmd);
 652
 653         if (transport_cmd_check_stop_to_fabric(cmd))
 654                 return;
 655         if (remove)
 656                 transport_put_cmd(cmd);
 657 }
 658
 659 static void target_complete_failure_work(struct work_struct *work)
 660 {
 661         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 662
 663         transport_generic_request_failure(cmd,
 664                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 665 }
 666
 667 /*
 668  * Used when asking transport to copy Sense Data from the underlying
 669  * Linux/SCSI struct scsi_cmnd
 670  */
 671 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 672 {
 673         struct se_device *dev = cmd->se_dev;
 674
 675         WARN_ON(!cmd->se_lun);
 676
 677         if (!dev)
 678                 return NULL;
 679
 680         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 681                 return NULL;
 682
 683         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 684
 685         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 686                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 687         return cmd->sense_buffer;
 688 }
 689
 690 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 691 {
 692         struct se_device *dev = cmd->se_dev;
 693         int success = scsi_status == GOOD;
 694         unsigned long flags;
 695
 696         cmd->scsi_status = scsi_status;
 697
 698
 699         spin_lock_irqsave(&cmd->t_state_lock, flags);
 700         cmd->transport_state &= ~CMD_T_BUSY;
 701
 702         if (dev && dev->transport->transport_complete) {
 703                 dev->transport->transport_complete(cmd,
 704                                 cmd->t_data_sg,
 705                                 transport_get_sense_buffer(cmd));
 706                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 707                         success = 1;
 708         }
 709
 710         /*
 711          * See if we are waiting to complete for an exception condition.
 712          */
 713         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
 714                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 715                 complete(&cmd->task_stop_comp);
 716                 return;
 717         }
 718
 719         /*
 720          * Check for case where an explicit ABORT_TASK has been received
 721          * and transport_wait_for_tasks() will be waiting for completion..
 722          */
 723         if (cmd->transport_state & CMD_T_ABORTED &&
 724             cmd->transport_state & CMD_T_STOP) {
 725                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 726                 complete_all(&cmd->t_transport_stop_comp);
 727                 return;
 728         } else if (!success) {
 729                 INIT_WORK(&cmd->work, target_complete_failure_work);
 730         } else {
 731                 INIT_WORK(&cmd->work, target_complete_ok_work);
 732         }
 733
 734         cmd->t_state = TRANSPORT_COMPLETE;
 735         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 736         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 737
 738         queue_work(target_completion_wq, &cmd->work);
 739 }
 740 EXPORT_SYMBOL(target_complete_cmd);
 741
 742 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 743 {
 744         if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
 745                 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 746                         cmd->residual_count += cmd->data_length - length;
 747                 } else {
 748                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
 749                         cmd->residual_count = cmd->data_length - length;
 750                 }
 751
 752                 cmd->data_length = length;
 753         }
 754
 755         target_complete_cmd(cmd, scsi_status);
 756 }
 757 EXPORT_SYMBOL(target_complete_cmd_with_length);
 758
 759 static void target_add_to_state_list(struct se_cmd *cmd)
 760 {
 761         struct se_device *dev = cmd->se_dev;
 762         unsigned long flags;
 763
 764         spin_lock_irqsave(&dev->execute_task_lock, flags);
 765         if (!cmd->state_active) {
 766                 list_add_tail(&cmd->state_list, &dev->state_list);
 767                 cmd->state_active = true;
 768         }
 769         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 770 }
 771
 772 /*
 773  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 774  */
 775 static void transport_write_pending_qf(struct se_cmd *cmd);
 776 static void transport_complete_qf(struct se_cmd *cmd);
 777
 778 void target_qf_do_work(struct work_struct *work)
 779 {
 780         struct se_device *dev = container_of(work, struct se_device,
 781                                         qf_work_queue);
 782         LIST_HEAD(qf_cmd_list);
 783         struct se_cmd *cmd, *cmd_tmp;
 784
 785         spin_lock_irq(&dev->qf_cmd_lock);
 786         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 787         spin_unlock_irq(&dev->qf_cmd_lock);
 788
 789         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 790                 list_del(&cmd->se_qf_node);
 791                 atomic_dec_mb(&dev->dev_qf_count);
 792
 793                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 794                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 795                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 796                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 797                         : "UNKNOWN");
 798
 799                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 800                         transport_write_pending_qf(cmd);
 801                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 802                         transport_complete_qf(cmd);
 803         }
 804 }
 805
 806 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 807 {
 808         switch (cmd->data_direction) {
 809         case DMA_NONE:
 810                 return "NONE";
 811         case DMA_FROM_DEVICE:
 812                 return "READ";
 813         case DMA_TO_DEVICE:
 814                 return "WRITE";
 815         case DMA_BIDIRECTIONAL:
 816                 return "BIDI";
 817         default:
 818                 break;
 819         }
 820
 821         return "UNKNOWN";
 822 }
 823
 824 void transport_dump_dev_state(
 825         struct se_device *dev,
 826         char *b,
 827         int *bl)
 828 {
 829         *bl += sprintf(b + *bl, "Status: ");
 830         if (dev->export_count)
 831                 *bl += sprintf(b + *bl, "ACTIVATED");
 832         else
 833                 *bl += sprintf(b + *bl, "DEACTIVATED");
 834
 835         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 836         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 837                 dev->dev_attrib.block_size,
 838                 dev->dev_attrib.hw_max_sectors);
 839         *bl += sprintf(b + *bl, "        ");
 840 }
 841
 842 void transport_dump_vpd_proto_id(
 843         struct t10_vpd *vpd,
 844         unsigned char *p_buf,
 845         int p_buf_len)
 846 {
 847         unsigned char buf[VPD_TMP_BUF_SIZE];
 848         int len;
 849
 850         memset(buf, 0, VPD_TMP_BUF_SIZE);
 851         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 852
 853         switch (vpd->protocol_identifier) {
 854         case 0x00:
 855                 sprintf(buf+len, "Fibre Channel\n");
 856                 break;
 857         case 0x10:
 858                 sprintf(buf+len, "Parallel SCSI\n");
 859                 break;
 860         case 0x20:
 861                 sprintf(buf+len, "SSA\n");
 862                 break;
 863         case 0x30:
 864                 sprintf(buf+len, "IEEE 1394\n");
 865                 break;
 866         case 0x40:
 867                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 868                                 " Protocol\n");
 869                 break;
 870         case 0x50:
 871                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 872                 break;
 873         case 0x60:
 874                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 875                 break;
 876         case 0x70:
 877                 sprintf(buf+len, "Automation/Drive Interface Transport"
 878                                 " Protocol\n");
 879                 break;
 880         case 0x80:
 881                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 882                 break;
 883         default:
 884                 sprintf(buf+len, "Unknown 0x%02x\n",
 885                                 vpd->protocol_identifier);
 886                 break;
 887         }
 888
 889         if (p_buf)
 890                 strncpy(p_buf, buf, p_buf_len);
 891         else
 892                 pr_debug("%s", buf);
 893 }
 894
 895 void
 896 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 897 {
 898         /*
 899          * Check if the Protocol Identifier Valid (PIV) bit is set..
 900          *
 901          * from spc3r23.pdf section 7.5.1
 902          */
 903          if (page_83[1] & 0x80) {
 904                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 905                 vpd->protocol_identifier_set = 1;
 906                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 907         }
 908 }
 909 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 910
 911 int transport_dump_vpd_assoc(
 912         struct t10_vpd *vpd,
 913         unsigned char *p_buf,
 914         int p_buf_len)
 915 {
 916         unsigned char buf[VPD_TMP_BUF_SIZE];
 917         int ret = 0;
 918         int len;
 919
 920         memset(buf, 0, VPD_TMP_BUF_SIZE);
 921         len = sprintf(buf, "T10 VPD Identifier Association: ");
 922
 923         switch (vpd->association) {
 924         case 0x00:
 925                 sprintf(buf+len, "addressed logical unit\n");
 926                 break;
 927         case 0x10:
 928                 sprintf(buf+len, "target port\n");
 929                 break;
 930         case 0x20:
 931                 sprintf(buf+len, "SCSI target device\n");
 932                 break;
 933         default:
 934                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 935                 ret = -EINVAL;
 936                 break;
 937         }
 938
 939         if (p_buf)
 940                 strncpy(p_buf, buf, p_buf_len);
 941         else
 942                 pr_debug("%s", buf);
 943
 944         return ret;
 945 }
 946
 947 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 948 {
 949         /*
 950          * The VPD identification association..
 951          *
 952          * from spc3r23.pdf Section 7.6.3.1 Table 297
 953          */
 954         vpd->association = (page_83[1] & 0x30);
 955         return transport_dump_vpd_assoc(vpd, NULL, 0);
 956 }
 957 EXPORT_SYMBOL(transport_set_vpd_assoc);
 958
 959 int transport_dump_vpd_ident_type(
 960         struct t10_vpd *vpd,
 961         unsigned char *p_buf,
 962         int p_buf_len)
 963 {
 964         unsigned char buf[VPD_TMP_BUF_SIZE];
 965         int ret = 0;
 966         int len;
 967
 968         memset(buf, 0, VPD_TMP_BUF_SIZE);
 969         len = sprintf(buf, "T10 VPD Identifier Type: ");
 970
 971         switch (vpd->device_identifier_type) {
 972         case 0x00:
 973                 sprintf(buf+len, "Vendor specific\n");
 974                 break;
 975         case 0x01:
 976                 sprintf(buf+len, "T10 Vendor ID based\n");
 977                 break;
 978         case 0x02:
 979                 sprintf(buf+len, "EUI-64 based\n");
 980                 break;
 981         case 0x03:
 982                 sprintf(buf+len, "NAA\n");
 983                 break;
 984         case 0x04:
 985                 sprintf(buf+len, "Relative target port identifier\n");
 986                 break;
 987         case 0x08:
 988                 sprintf(buf+len, "SCSI name string\n");
 989                 break;
 990         default:
 991                 sprintf(buf+len, "Unsupported: 0x%02x\n",
 992                                 vpd->device_identifier_type);
 993                 ret = -EINVAL;
 994                 break;
 995         }
 996
 997         if (p_buf) {
 998                 if (p_buf_len < strlen(buf)+1)
 999                         return -EINVAL;
1000                 strncpy(p_buf, buf, p_buf_len);
1001         } else {
1002                 pr_debug("%s", buf);
1003         }
1004
1005         return ret;
1006 }
1007
1008 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1009 {
1010         /*
1011          * The VPD identifier type..
1012          *
1013          * from spc3r23.pdf Section 7.6.3.1 Table 298
1014          */
1015         vpd->device_identifier_type = (page_83[1] & 0x0f);
1016         return transport_dump_vpd_ident_type(vpd, NULL, 0);
1017 }
1018 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1019
1020 int transport_dump_vpd_ident(
1021         struct t10_vpd *vpd,
1022         unsigned char *p_buf,
1023         int p_buf_len)
1024 {
1025         unsigned char buf[VPD_TMP_BUF_SIZE];
1026         int ret = 0;
1027
1028         memset(buf, 0, VPD_TMP_BUF_SIZE);
1029
1030         switch (vpd->device_identifier_code_set) {
1031         case 0x01: /* Binary */
1032                 snprintf(buf, sizeof(buf),
1033                         "T10 VPD Binary Device Identifier: %s\n",
1034                         &vpd->device_identifier[0]);
1035                 break;
1036         case 0x02: /* ASCII */
1037                 snprintf(buf, sizeof(buf),
1038                         "T10 VPD ASCII Device Identifier: %s\n",
1039                         &vpd->device_identifier[0]);
1040                 break;
1041         case 0x03: /* UTF-8 */
1042                 snprintf(buf, sizeof(buf),
1043                         "T10 VPD UTF-8 Device Identifier: %s\n",
1044                         &vpd->device_identifier[0]);
1045                 break;
1046         default:
1047                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1048                         " 0x%02x", vpd->device_identifier_code_set);
1049                 ret = -EINVAL;
1050                 break;
1051         }
1052
1053         if (p_buf)
1054                 strncpy(p_buf, buf, p_buf_len);
1055         else
1056                 pr_debug("%s", buf);
1057
1058         return ret;
1059 }
1060
1061 int
1062 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1063 {
1064         static const char hex_str[] = "0123456789abcdef";
1065         int j = 0, i = 4; /* offset to start of the identifier */
1066
1067         /*
1068          * The VPD Code Set (encoding)
1069          *
1070          * from spc3r23.pdf Section 7.6.3.1 Table 296
1071          */
1072         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1073         switch (vpd->device_identifier_code_set) {
1074         case 0x01: /* Binary */
1075                 vpd->device_identifier[j++] =
1076                                 hex_str[vpd->device_identifier_type];
1077                 while (i < (4 + page_83[3])) {
1078                         vpd->device_identifier[j++] =
1079                                 hex_str[(page_83[i] & 0xf0) >> 4];
1080                         vpd->device_identifier[j++] =
1081                                 hex_str[page_83[i] & 0x0f];
1082                         i++;
1083                 }
1084                 break;
1085         case 0x02: /* ASCII */
1086         case 0x03: /* UTF-8 */
1087                 while (i < (4 + page_83[3]))
1088                         vpd->device_identifier[j++] = page_83[i++];
1089                 break;
1090         default:
1091                 break;
1092         }
1093
1094         return transport_dump_vpd_ident(vpd, NULL, 0);
1095 }
1096 EXPORT_SYMBOL(transport_set_vpd_ident);
1097
1098 sense_reason_t
1099 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1100 {
1101         struct se_device *dev = cmd->se_dev;
1102
1103         if (cmd->unknown_data_length) {
1104                 cmd->data_length = size;
1105         } else if (size != cmd->data_length) {
1106                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1107                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1108                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1109                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1110
1111                 if (cmd->data_direction == DMA_TO_DEVICE) {
1112                         pr_err("Rejecting underflow/overflow"
1113                                         " WRITE data\n");
1114                         return TCM_INVALID_CDB_FIELD;
1115                 }
1116                 /*
1117                  * Reject READ_* or WRITE_* with overflow/underflow for
1118                  * type SCF_SCSI_DATA_CDB.
1119                  */
1120                 if (dev->dev_attrib.block_size != 512)  {
1121                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1122                                 " CDB on non 512-byte sector setup subsystem"
1123                                 " plugin: %s\n", dev->transport->name);
1124                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1125                         return TCM_INVALID_CDB_FIELD;
1126                 }
1127                 /*
1128                  * For the overflow case keep the existing fabric provided
1129                  * ->data_length.  Otherwise for the underflow case, reset
1130                  * ->data_length to the smaller SCSI expected data transfer
1131                  * length.
1132                  */
1133                 if (size > cmd->data_length) {
1134                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1135                         cmd->residual_count = (size - cmd->data_length);
1136                 } else {
1137                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1138                         cmd->residual_count = (cmd->data_length - size);
1139                         cmd->data_length = size;
1140                 }
1141         }
1142
1143         return 0;
1144
1145 }
1146
1147 /*
1148  * Used by fabric modules containing a local struct se_cmd within their
1149  * fabric dependent per I/O descriptor.
1150  *
1151  * Preserves the value of @cmd->tag.
1152  */
1153 void transport_init_se_cmd(
1154         struct se_cmd *cmd,
1155         const struct target_core_fabric_ops *tfo,
1156         struct se_session *se_sess,
1157         u32 data_length,
1158         int data_direction,
1159         int task_attr,
1160         unsigned char *sense_buffer)
1161 {
1162         INIT_LIST_HEAD(&cmd->se_delayed_node);
1163         INIT_LIST_HEAD(&cmd->se_qf_node);
1164         INIT_LIST_HEAD(&cmd->se_cmd_list);
1165         INIT_LIST_HEAD(&cmd->state_list);
1166         init_completion(&cmd->t_transport_stop_comp);
1167         init_completion(&cmd->cmd_wait_comp);
1168         init_completion(&cmd->task_stop_comp);
1169         spin_lock_init(&cmd->t_state_lock);
1170         kref_init(&cmd->cmd_kref);
1171         cmd->transport_state = CMD_T_DEV_ACTIVE;
1172
1173         cmd->se_tfo = tfo;
1174         cmd->se_sess = se_sess;
1175         cmd->data_length = data_length;
1176         cmd->data_direction = data_direction;
1177         cmd->sam_task_attr = task_attr;
1178         cmd->sense_buffer = sense_buffer;
1179
1180         cmd->state_active = false;
1181 }
1182 EXPORT_SYMBOL(transport_init_se_cmd);
1183
1184 static sense_reason_t
1185 transport_check_alloc_task_attr(struct se_cmd *cmd)
1186 {
1187         struct se_device *dev = cmd->se_dev;
1188
1189         /*
1190          * Check if SAM Task Attribute emulation is enabled for this
1191          * struct se_device storage object
1192          */
1193         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1194                 return 0;
1195
1196         if (cmd->sam_task_attr == TCM_ACA_TAG) {
1197                 pr_debug("SAM Task Attribute ACA"
1198                         " emulation is not supported\n");
1199                 return TCM_INVALID_CDB_FIELD;
1200         }
1201         /*
1202          * Used to determine when ORDERED commands should go from
1203          * Dormant to Active status.
1204          */
1205         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1206         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1207                         cmd->se_ordered_id, cmd->sam_task_attr,
1208                         dev->transport->name);
1209         return 0;
1210 }
1211
1212 sense_reason_t
1213 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1214 {
1215         struct se_device *dev = cmd->se_dev;
1216         sense_reason_t ret;
1217
1218         /*
1219          * Ensure that the received CDB is less than the max (252 + 8) bytes
1220          * for VARIABLE_LENGTH_CMD
1221          */
1222         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1223                 pr_err("Received SCSI CDB with command_size: %d that"
1224                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1225                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1226                 return TCM_INVALID_CDB_FIELD;
1227         }
1228         /*
1229          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1230          * allocate the additional extended CDB buffer now..  Otherwise
1231          * setup the pointer from __t_task_cdb to t_task_cdb.
1232          */
1233         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1234                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1235                                                 GFP_KERNEL);
1236                 if (!cmd->t_task_cdb) {
1237                         pr_err("Unable to allocate cmd->t_task_cdb"
1238                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1239                                 scsi_command_size(cdb),
1240                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1241                         return TCM_OUT_OF_RESOURCES;
1242                 }
1243         } else
1244                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1245         /*
1246          * Copy the original CDB into cmd->
1247          */
1248         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1249
1250         trace_target_sequencer_start(cmd);
1251
1252         /*
1253          * Check for an existing UNIT ATTENTION condition
1254          */
1255         ret = target_scsi3_ua_check(cmd);
1256         if (ret)
1257                 return ret;
1258
1259         ret = target_alua_state_check(cmd);
1260         if (ret)
1261                 return ret;
1262
1263         ret = target_check_reservation(cmd);
1264         if (ret) {
1265                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1266                 return ret;
1267         }
1268
1269         ret = dev->transport->parse_cdb(cmd);
1270         if (ret)
1271                 return ret;
1272
1273         ret = transport_check_alloc_task_attr(cmd);
1274         if (ret)
1275                 return ret;
1276
1277         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1278
1279         spin_lock(&cmd->se_lun->lun_sep_lock);
1280         if (cmd->se_lun->lun_sep)
1281                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1282         spin_unlock(&cmd->se_lun->lun_sep_lock);
1283         return 0;
1284 }
1285 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1286
1287 /*
1288  * Used by fabric module frontends to queue tasks directly.
1289  * Many only be used from process context only
1290  */
1291 int transport_handle_cdb_direct(
1292         struct se_cmd *cmd)
1293 {
1294         sense_reason_t ret;
1295
1296         if (!cmd->se_lun) {
1297                 dump_stack();
1298                 pr_err("cmd->se_lun is NULL\n");
1299                 return -EINVAL;
1300         }
1301         if (in_interrupt()) {
1302                 dump_stack();
1303                 pr_err("transport_generic_handle_cdb cannot be called"
1304                                 " from interrupt context\n");
1305                 return -EINVAL;
1306         }
1307         /*
1308          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1309          * outstanding descriptors are handled correctly during shutdown via
1310          * transport_wait_for_tasks()
1311          *
1312          * Also, we don't take cmd->t_state_lock here as we only expect
1313          * this to be called for initial descriptor submission.
1314          */
1315         cmd->t_state = TRANSPORT_NEW_CMD;
1316         cmd->transport_state |= CMD_T_ACTIVE;
1317
1318         /*
1319          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1320          * so follow TRANSPORT_NEW_CMD processing thread context usage
1321          * and call transport_generic_request_failure() if necessary..
1322          */
1323         ret = transport_generic_new_cmd(cmd);
1324         if (ret)
1325                 transport_generic_request_failure(cmd, ret);
1326         return 0;
1327 }
1328 EXPORT_SYMBOL(transport_handle_cdb_direct);
1329
1330 sense_reason_t
1331 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1332                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1333 {
1334         if (!sgl || !sgl_count)
1335                 return 0;
1336
1337         /*
1338          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1339          * scatterlists already have been set to follow what the fabric
1340          * passes for the original expected data transfer length.
1341          */
1342         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1343                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1344                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1345                 return TCM_INVALID_CDB_FIELD;
1346         }
1347
1348         cmd->t_data_sg = sgl;
1349         cmd->t_data_nents = sgl_count;
1350         cmd->t_bidi_data_sg = sgl_bidi;
1351         cmd->t_bidi_data_nents = sgl_bidi_count;
1352
1353         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1354         return 0;
1355 }
1356
1357 /*
1358  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1359  *                       se_cmd + use pre-allocated SGL memory.
1360  *
1361  * @se_cmd: command descriptor to submit
1362  * @se_sess: associated se_sess for endpoint
1363  * @cdb: pointer to SCSI CDB
1364  * @sense: pointer to SCSI sense buffer
1365  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1366  * @data_length: fabric expected data transfer length
1367  * @task_addr: SAM task attribute
1368  * @data_dir: DMA data direction
1369  * @flags: flags for command submission from target_sc_flags_tables
1370  * @sgl: struct scatterlist memory for unidirectional mapping
1371  * @sgl_count: scatterlist count for unidirectional mapping
1372  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1373  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1374  * @sgl_prot: struct scatterlist memory protection information
1375  * @sgl_prot_count: scatterlist count for protection information
1376  *
1377  * Task tags are supported if the caller has set @se_cmd->tag.
1378  *
1379  * Returns non zero to signal active I/O shutdown failure.  All other
1380  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1381  * but still return zero here.
1382  *
1383  * This may only be called from process context, and also currently
1384  * assumes internal allocation of fabric payload buffer by target-core.
1385  */
1386 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1387                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1388                 u32 data_length, int task_attr, int data_dir, int flags,
1389                 struct scatterlist *sgl, u32 sgl_count,
1390                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1391                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1392 {
1393         struct se_portal_group *se_tpg;
1394         sense_reason_t rc;
1395         int ret;
1396
1397         se_tpg = se_sess->se_tpg;
1398         BUG_ON(!se_tpg);
1399         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1400         BUG_ON(in_interrupt());
1401         /*
1402          * Initialize se_cmd for target operation.  From this point
1403          * exceptions are handled by sending exception status via
1404          * target_core_fabric_ops->queue_status() callback
1405          */
1406         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1407                                 data_length, data_dir, task_attr, sense);
1408         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1409                 se_cmd->unknown_data_length = 1;
1410         /*
1411          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1412          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1413          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1414          * kref_put() to happen during fabric packet acknowledgement.
1415          */
1416         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1417         if (ret)
1418                 return ret;
1419         /*
1420          * Signal bidirectional data payloads to target-core
1421          */
1422         if (flags & TARGET_SCF_BIDI_OP)
1423                 se_cmd->se_cmd_flags |= SCF_BIDI;
1424         /*
1425          * Locate se_lun pointer and attach it to struct se_cmd
1426          */
1427         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1428         if (rc) {
1429                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1430                 target_put_sess_cmd(se_cmd);
1431                 return 0;
1432         }
1433
1434         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1435         if (rc != 0) {
1436                 transport_generic_request_failure(se_cmd, rc);
1437                 return 0;
1438         }
1439
1440         /*
1441          * Save pointers for SGLs containing protection information,
1442          * if present.
1443          */
1444         if (sgl_prot_count) {
1445                 se_cmd->t_prot_sg = sgl_prot;
1446                 se_cmd->t_prot_nents = sgl_prot_count;
1447                 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1448         }
1449
1450         /*
1451          * When a non zero sgl_count has been passed perform SGL passthrough
1452          * mapping for pre-allocated fabric memory instead of having target
1453          * core perform an internal SGL allocation..
1454          */
1455         if (sgl_count != 0) {
1456                 BUG_ON(!sgl);
1457
1458                 /*
1459                  * A work-around for tcm_loop as some userspace code via
1460                  * scsi-generic do not memset their associated read buffers,
1461                  * so go ahead and do that here for type non-data CDBs.  Also
1462                  * note that this is currently guaranteed to be a single SGL
1463                  * for this case by target core in target_setup_cmd_from_cdb()
1464                  * -> transport_generic_cmd_sequencer().
1465                  */
1466                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1467                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1468                         unsigned char *buf = NULL;
1469
1470                         if (sgl)
1471                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1472
1473                         if (buf) {
1474                                 memset(buf, 0, sgl->length);
1475                                 kunmap(sg_page(sgl));
1476                         }
1477                 }
1478
1479                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1480                                 sgl_bidi, sgl_bidi_count);
1481                 if (rc != 0) {
1482                         transport_generic_request_failure(se_cmd, rc);
1483                         return 0;
1484                 }
1485         }
1486
1487         /*
1488          * Check if we need to delay processing because of ALUA
1489          * Active/NonOptimized primary access state..
1490          */
1491         core_alua_check_nonop_delay(se_cmd);
1492
1493         transport_handle_cdb_direct(se_cmd);
1494         return 0;
1495 }
1496 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1497
1498 /*
1499  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1500  *
1501  * @se_cmd: command descriptor to submit
1502  * @se_sess: associated se_sess for endpoint
1503  * @cdb: pointer to SCSI CDB
1504  * @sense: pointer to SCSI sense buffer
1505  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1506  * @data_length: fabric expected data transfer length
1507  * @task_addr: SAM task attribute
1508  * @data_dir: DMA data direction
1509  * @flags: flags for command submission from target_sc_flags_tables
1510  *
1511  * Task tags are supported if the caller has set @se_cmd->tag.
1512  *
1513  * Returns non zero to signal active I/O shutdown failure.  All other
1514  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1515  * but still return zero here.
1516  *
1517  * This may only be called from process context, and also currently
1518  * assumes internal allocation of fabric payload buffer by target-core.
1519  *
1520  * It also assumes interal target core SGL memory allocation.
1521  */
1522 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1523                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1524                 u32 data_length, int task_attr, int data_dir, int flags)
1525 {
1526         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1527                         unpacked_lun, data_length, task_attr, data_dir,
1528                         flags, NULL, 0, NULL, 0, NULL, 0);
1529 }
1530 EXPORT_SYMBOL(target_submit_cmd);
1531
1532 static void target_complete_tmr_failure(struct work_struct *work)
1533 {
1534         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1535
1536         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1537         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1538
1539         transport_cmd_check_stop_to_fabric(se_cmd);
1540 }
1541
1542 /**
1543  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1544  *                     for TMR CDBs
1545  *
1546  * @se_cmd: command descriptor to submit
1547  * @se_sess: associated se_sess for endpoint
1548  * @sense: pointer to SCSI sense buffer
1549  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1550  * @fabric_context: fabric context for TMR req
1551  * @tm_type: Type of TM request
1552  * @gfp: gfp type for caller
1553  * @tag: referenced task tag for TMR_ABORT_TASK
1554  * @flags: submit cmd flags
1555  *
1556  * Callable from all contexts.
1557  **/
1558
1559 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1560                 unsigned char *sense, u32 unpacked_lun,
1561                 void *fabric_tmr_ptr, unsigned char tm_type,
1562                 gfp_t gfp, unsigned int tag, int flags)
1563 {
1564         struct se_portal_group *se_tpg;
1565         int ret;
1566
1567         se_tpg = se_sess->se_tpg;
1568         BUG_ON(!se_tpg);
1569
1570         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1571                               0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1572         /*
1573          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1574          * allocation failure.
1575          */
1576         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1577         if (ret < 0)
1578                 return -ENOMEM;
1579
1580         if (tm_type == TMR_ABORT_TASK)
1581                 se_cmd->se_tmr_req->ref_task_tag = tag;
1582
1583         /* See target_submit_cmd for commentary */
1584         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1585         if (ret) {
1586                 core_tmr_release_req(se_cmd->se_tmr_req);
1587                 return ret;
1588         }
1589
1590         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1591         if (ret) {
1592                 /*
1593                  * For callback during failure handling, push this work off
1594                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1595                  */
1596                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1597                 schedule_work(&se_cmd->work);
1598                 return 0;
1599         }
1600         transport_generic_handle_tmr(se_cmd);
1601         return 0;
1602 }
1603 EXPORT_SYMBOL(target_submit_tmr);
1604
1605 /*
1606  * If the cmd is active, request it to be stopped and sleep until it
1607  * has completed.
1608  */
1609 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1610         __releases(&cmd->t_state_lock)
1611         __acquires(&cmd->t_state_lock)
1612 {
1613         bool was_active = false;
1614
1615         if (cmd->transport_state & CMD_T_BUSY) {
1616                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1617                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1618
1619                 pr_debug("cmd %p waiting to complete\n", cmd);
1620                 wait_for_completion(&cmd->task_stop_comp);
1621                 pr_debug("cmd %p stopped successfully\n", cmd);
1622
1623                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1624                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1625                 cmd->transport_state &= ~CMD_T_BUSY;
1626                 was_active = true;
1627         }
1628
1629         return was_active;
1630 }
1631
1632 /*
1633  * Handle SAM-esque emulation for generic transport request failures.
1634  */
1635 void transport_generic_request_failure(struct se_cmd *cmd,
1636                 sense_reason_t sense_reason)
1637 {
1638         int ret = 0;
1639
1640         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08llx"
1641                 " CDB: 0x%02x\n", cmd, cmd->tag, cmd->t_task_cdb[0]);
1642         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1643                 cmd->se_tfo->get_cmd_state(cmd),
1644                 cmd->t_state, sense_reason);
1645         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1646                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1647                 (cmd->transport_state & CMD_T_STOP) != 0,
1648                 (cmd->transport_state & CMD_T_SENT) != 0);
1649
1650         /*
1651          * For SAM Task Attribute emulation for failed struct se_cmd
1652          */
1653         transport_complete_task_attr(cmd);
1654         /*
1655          * Handle special case for COMPARE_AND_WRITE failure, where the
1656          * callback is expected to drop the per device ->caw_sem.
1657          */
1658         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1659              cmd->transport_complete_callback)
1660                 cmd->transport_complete_callback(cmd, false);
1661
1662         switch (sense_reason) {
1663         case TCM_NON_EXISTENT_LUN:
1664         case TCM_UNSUPPORTED_SCSI_OPCODE:
1665         case TCM_INVALID_CDB_FIELD:
1666         case TCM_INVALID_PARAMETER_LIST:
1667         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1668         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1669         case TCM_UNKNOWN_MODE_PAGE:
1670         case TCM_WRITE_PROTECTED:
1671         case TCM_ADDRESS_OUT_OF_RANGE:
1672         case TCM_CHECK_CONDITION_ABORT_CMD:
1673         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1674         case TCM_CHECK_CONDITION_NOT_READY:
1675         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1676         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1677         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1678                 break;
1679         case TCM_OUT_OF_RESOURCES:
1680                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1681                 break;
1682         case TCM_RESERVATION_CONFLICT:
1683                 /*
1684                  * No SENSE Data payload for this case, set SCSI Status
1685                  * and queue the response to $FABRIC_MOD.
1686                  *
1687                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1688                  */
1689                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1690                 /*
1691                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1692                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1693                  * CONFLICT STATUS.
1694                  *
1695                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1696                  */
1697                 if (cmd->se_sess &&
1698                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1699                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1700                                 cmd->orig_fe_lun, 0x2C,
1701                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1702
1703                 trace_target_cmd_complete(cmd);
1704                 ret = cmd->se_tfo-> queue_status(cmd);
1705                 if (ret == -EAGAIN || ret == -ENOMEM)
1706                         goto queue_full;
1707                 goto check_stop;
1708         default:
1709                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1710                         cmd->t_task_cdb[0], sense_reason);
1711                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1712                 break;
1713         }
1714
1715         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1716         if (ret == -EAGAIN || ret == -ENOMEM)
1717                 goto queue_full;
1718
1719 check_stop:
1720         transport_lun_remove_cmd(cmd);
1721         if (!transport_cmd_check_stop_to_fabric(cmd))
1722                 ;
1723         return;
1724
1725 queue_full:
1726         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1727         transport_handle_queue_full(cmd, cmd->se_dev);
1728 }
1729 EXPORT_SYMBOL(transport_generic_request_failure);
1730
1731 void __target_execute_cmd(struct se_cmd *cmd)
1732 {
1733         sense_reason_t ret;
1734
1735         if (cmd->execute_cmd) {
1736                 ret = cmd->execute_cmd(cmd);
1737                 if (ret) {
1738                         spin_lock_irq(&cmd->t_state_lock);
1739                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1740                         spin_unlock_irq(&cmd->t_state_lock);
1741
1742                         transport_generic_request_failure(cmd, ret);
1743                 }
1744         }
1745 }
1746
1747 static int target_write_prot_action(struct se_cmd *cmd)
1748 {
1749         u32 sectors;
1750         /*
1751          * Perform WRITE_INSERT of PI using software emulation when backend
1752          * device has PI enabled, if the transport has not already generated
1753          * PI using hardware WRITE_INSERT offload.
1754          */
1755         switch (cmd->prot_op) {
1756         case TARGET_PROT_DOUT_INSERT:
1757                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1758                         sbc_dif_generate(cmd);
1759                 break;
1760         case TARGET_PROT_DOUT_STRIP:
1761                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1762                         break;
1763
1764                 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1765                 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1766                                              sectors, 0, cmd->t_prot_sg, 0);
1767                 if (unlikely(cmd->pi_err)) {
1768                         spin_lock_irq(&cmd->t_state_lock);
1769                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1770                         spin_unlock_irq(&cmd->t_state_lock);
1771                         transport_generic_request_failure(cmd, cmd->pi_err);
1772                         return -1;
1773                 }
1774                 break;
1775         default:
1776                 break;
1777         }
1778
1779         return 0;
1780 }
1781
1782 static bool target_handle_task_attr(struct se_cmd *cmd)
1783 {
1784         struct se_device *dev = cmd->se_dev;
1785
1786         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1787                 return false;
1788
1789         /*
1790          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1791          * to allow the passed struct se_cmd list of tasks to the front of the list.
1792          */
1793         switch (cmd->sam_task_attr) {
1794         case TCM_HEAD_TAG:
1795                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1796                          "se_ordered_id: %u\n",
1797                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1798                 return false;
1799         case TCM_ORDERED_TAG:
1800                 atomic_inc_mb(&dev->dev_ordered_sync);
1801
1802                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1803                          " se_ordered_id: %u\n",
1804                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1805
1806                 /*
1807                  * Execute an ORDERED command if no other older commands
1808                  * exist that need to be completed first.
1809                  */
1810                 if (!atomic_read(&dev->simple_cmds))
1811                         return false;
1812                 break;
1813         default:
1814                 /*
1815                  * For SIMPLE and UNTAGGED Task Attribute commands
1816                  */
1817                 atomic_inc_mb(&dev->simple_cmds);
1818                 break;
1819         }
1820
1821         if (atomic_read(&dev->dev_ordered_sync) == 0)
1822                 return false;
1823
1824         spin_lock(&dev->delayed_cmd_lock);
1825         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1826         spin_unlock(&dev->delayed_cmd_lock);
1827
1828         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1829                 " delayed CMD list, se_ordered_id: %u\n",
1830                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1831                 cmd->se_ordered_id);
1832         return true;
1833 }
1834
1835 void target_execute_cmd(struct se_cmd *cmd)
1836 {
1837         /*
1838          * If the received CDB has aleady been aborted stop processing it here.
1839          */
1840         if (transport_check_aborted_status(cmd, 1))
1841                 return;
1842
1843         /*
1844          * Determine if frontend context caller is requesting the stopping of
1845          * this command for frontend exceptions.
1846          */
1847         spin_lock_irq(&cmd->t_state_lock);
1848         if (cmd->transport_state & CMD_T_STOP) {
1849                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1850                         __func__, __LINE__, cmd->tag);
1851
1852                 spin_unlock_irq(&cmd->t_state_lock);
1853                 complete_all(&cmd->t_transport_stop_comp);
1854                 return;
1855         }
1856
1857         cmd->t_state = TRANSPORT_PROCESSING;
1858         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1859         spin_unlock_irq(&cmd->t_state_lock);
1860
1861         if (target_write_prot_action(cmd))
1862                 return;
1863
1864         if (target_handle_task_attr(cmd)) {
1865                 spin_lock_irq(&cmd->t_state_lock);
1866                 cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1867                 spin_unlock_irq(&cmd->t_state_lock);
1868                 return;
1869         }
1870
1871         __target_execute_cmd(cmd);
1872 }
1873 EXPORT_SYMBOL(target_execute_cmd);
1874
1875 /*
1876  * Process all commands up to the last received ORDERED task attribute which
1877  * requires another blocking boundary
1878  */
1879 static void target_restart_delayed_cmds(struct se_device *dev)
1880 {
1881         for (;;) {
1882                 struct se_cmd *cmd;
1883
1884                 spin_lock(&dev->delayed_cmd_lock);
1885                 if (list_empty(&dev->delayed_cmd_list)) {
1886                         spin_unlock(&dev->delayed_cmd_lock);
1887                         break;
1888                 }
1889
1890                 cmd = list_entry(dev->delayed_cmd_list.next,
1891                                  struct se_cmd, se_delayed_node);
1892                 list_del(&cmd->se_delayed_node);
1893                 spin_unlock(&dev->delayed_cmd_lock);
1894
1895                 __target_execute_cmd(cmd);
1896
1897                 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1898                         break;
1899         }
1900 }
1901
1902 /*
1903  * Called from I/O completion to determine which dormant/delayed
1904  * and ordered cmds need to have their tasks added to the execution queue.
1905  */
1906 static void transport_complete_task_attr(struct se_cmd *cmd)
1907 {
1908         struct se_device *dev = cmd->se_dev;
1909
1910         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1911                 return;
1912
1913         if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1914                 atomic_dec_mb(&dev->simple_cmds);
1915                 dev->dev_cur_ordered_id++;
1916                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1917                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1918                         cmd->se_ordered_id);
1919         } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1920                 dev->dev_cur_ordered_id++;
1921                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1922                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1923                         cmd->se_ordered_id);
1924         } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1925                 atomic_dec_mb(&dev->dev_ordered_sync);
1926
1927                 dev->dev_cur_ordered_id++;
1928                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1929                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1930         }
1931
1932         target_restart_delayed_cmds(dev);
1933 }
1934
1935 static void transport_complete_qf(struct se_cmd *cmd)
1936 {
1937         int ret = 0;
1938
1939         transport_complete_task_attr(cmd);
1940
1941         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1942                 trace_target_cmd_complete(cmd);
1943                 ret = cmd->se_tfo->queue_status(cmd);
1944                 goto out;
1945         }
1946
1947         switch (cmd->data_direction) {
1948         case DMA_FROM_DEVICE:
1949                 trace_target_cmd_complete(cmd);
1950                 ret = cmd->se_tfo->queue_data_in(cmd);
1951                 break;
1952         case DMA_TO_DEVICE:
1953                 if (cmd->se_cmd_flags & SCF_BIDI) {
1954                         ret = cmd->se_tfo->queue_data_in(cmd);
1955                         break;
1956                 }
1957                 /* Fall through for DMA_TO_DEVICE */
1958         case DMA_NONE:
1959                 trace_target_cmd_complete(cmd);
1960                 ret = cmd->se_tfo->queue_status(cmd);
1961                 break;
1962         default:
1963                 break;
1964         }
1965
1966 out:
1967         if (ret < 0) {
1968                 transport_handle_queue_full(cmd, cmd->se_dev);
1969                 return;
1970         }
1971         transport_lun_remove_cmd(cmd);
1972         transport_cmd_check_stop_to_fabric(cmd);
1973 }
1974
1975 static void transport_handle_queue_full(
1976         struct se_cmd *cmd,
1977         struct se_device *dev)
1978 {
1979         spin_lock_irq(&dev->qf_cmd_lock);
1980         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1981         atomic_inc_mb(&dev->dev_qf_count);
1982         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1983
1984         schedule_work(&cmd->se_dev->qf_work_queue);
1985 }
1986
1987 static bool target_read_prot_action(struct se_cmd *cmd)
1988 {
1989         switch (cmd->prot_op) {
1990         case TARGET_PROT_DIN_STRIP:
1991                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
1992                         u32 sectors = cmd->data_length >>
1993                                   ilog2(cmd->se_dev->dev_attrib.block_size);
1994
1995                         cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1996                                                      sectors, 0, cmd->t_prot_sg,
1997                                                      0);
1998                         if (cmd->pi_err)
1999                                 return true;
2000                 }
2001                 break;
2002         case TARGET_PROT_DIN_INSERT:
2003                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2004                         break;
2005
2006                 sbc_dif_generate(cmd);
2007                 break;
2008         default:
2009                 break;
2010         }
2011
2012         return false;
2013 }
2014
2015 static void target_complete_ok_work(struct work_struct *work)
2016 {
2017         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2018         int ret;
2019
2020         /*
2021          * Check if we need to move delayed/dormant tasks from cmds on the
2022          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2023          * Attribute.
2024          */
2025         transport_complete_task_attr(cmd);
2026
2027         /*
2028          * Check to schedule QUEUE_FULL work, or execute an existing
2029          * cmd->transport_qf_callback()
2030          */
2031         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2032                 schedule_work(&cmd->se_dev->qf_work_queue);
2033
2034         /*
2035          * Check if we need to send a sense buffer from
2036          * the struct se_cmd in question.
2037          */
2038         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2039                 WARN_ON(!cmd->scsi_status);
2040                 ret = transport_send_check_condition_and_sense(
2041                                         cmd, 0, 1);
2042                 if (ret == -EAGAIN || ret == -ENOMEM)
2043                         goto queue_full;
2044
2045                 transport_lun_remove_cmd(cmd);
2046                 transport_cmd_check_stop_to_fabric(cmd);
2047                 return;
2048         }
2049         /*
2050          * Check for a callback, used by amongst other things
2051          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2052          */
2053         if (cmd->transport_complete_callback) {
2054                 sense_reason_t rc;
2055
2056                 rc = cmd->transport_complete_callback(cmd, true);
2057                 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
2058                         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2059                             !cmd->data_length)
2060                                 goto queue_rsp;
2061
2062                         return;
2063                 } else if (rc) {
2064                         ret = transport_send_check_condition_and_sense(cmd,
2065                                                 rc, 0);
2066                         if (ret == -EAGAIN || ret == -ENOMEM)
2067                                 goto queue_full;
2068
2069                         transport_lun_remove_cmd(cmd);
2070                         transport_cmd_check_stop_to_fabric(cmd);
2071                         return;
2072                 }
2073         }
2074
2075 queue_rsp:
2076         switch (cmd->data_direction) {
2077         case DMA_FROM_DEVICE:
2078                 spin_lock(&cmd->se_lun->lun_sep_lock);
2079                 if (cmd->se_lun->lun_sep) {
2080                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
2081                                         cmd->data_length;
2082                 }
2083                 spin_unlock(&cmd->se_lun->lun_sep_lock);
2084                 /*
2085                  * Perform READ_STRIP of PI using software emulation when
2086                  * backend had PI enabled, if the transport will not be
2087                  * performing hardware READ_STRIP offload.
2088                  */
2089                 if (target_read_prot_action(cmd)) {
2090                         ret = transport_send_check_condition_and_sense(cmd,
2091                                                 cmd->pi_err, 0);
2092                         if (ret == -EAGAIN || ret == -ENOMEM)
2093                                 goto queue_full;
2094
2095                         transport_lun_remove_cmd(cmd);
2096                         transport_cmd_check_stop_to_fabric(cmd);
2097                         return;
2098                 }
2099
2100                 trace_target_cmd_complete(cmd);
2101                 ret = cmd->se_tfo->queue_data_in(cmd);
2102                 if (ret == -EAGAIN || ret == -ENOMEM)
2103                         goto queue_full;
2104                 break;
2105         case DMA_TO_DEVICE:
2106                 spin_lock(&cmd->se_lun->lun_sep_lock);
2107                 if (cmd->se_lun->lun_sep) {
2108                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
2109                                 cmd->data_length;
2110                 }
2111                 spin_unlock(&cmd->se_lun->lun_sep_lock);
2112                 /*
2113                  * Check if we need to send READ payload for BIDI-COMMAND
2114                  */
2115                 if (cmd->se_cmd_flags & SCF_BIDI) {
2116                         spin_lock(&cmd->se_lun->lun_sep_lock);
2117                         if (cmd->se_lun->lun_sep) {
2118                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
2119                                         cmd->data_length;
2120                         }
2121                         spin_unlock(&cmd->se_lun->lun_sep_lock);
2122                         ret = cmd->se_tfo->queue_data_in(cmd);
2123                         if (ret == -EAGAIN || ret == -ENOMEM)
2124                                 goto queue_full;
2125                         break;
2126                 }
2127                 /* Fall through for DMA_TO_DEVICE */
2128         case DMA_NONE:
2129                 trace_target_cmd_complete(cmd);
2130                 ret = cmd->se_tfo->queue_status(cmd);
2131                 if (ret == -EAGAIN || ret == -ENOMEM)
2132                         goto queue_full;
2133                 break;
2134         default:
2135                 break;
2136         }
2137
2138         transport_lun_remove_cmd(cmd);
2139         transport_cmd_check_stop_to_fabric(cmd);
2140         return;
2141
2142 queue_full:
2143         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2144                 " data_direction: %d\n", cmd, cmd->data_direction);
2145         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2146         transport_handle_queue_full(cmd, cmd->se_dev);
2147 }
2148
2149 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2150 {
2151         struct scatterlist *sg;
2152         int count;
2153
2154         for_each_sg(sgl, sg, nents, count)
2155                 __free_page(sg_page(sg));
2156
2157         kfree(sgl);
2158 }
2159
2160 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2161 {
2162         /*
2163          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2164          * emulation, and free + reset pointers if necessary..
2165          */
2166         if (!cmd->t_data_sg_orig)
2167                 return;
2168
2169         kfree(cmd->t_data_sg);
2170         cmd->t_data_sg = cmd->t_data_sg_orig;
2171         cmd->t_data_sg_orig = NULL;
2172         cmd->t_data_nents = cmd->t_data_nents_orig;
2173         cmd->t_data_nents_orig = 0;
2174 }
2175
2176 static inline void transport_free_pages(struct se_cmd *cmd)
2177 {
2178         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2179                 transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2180                 cmd->t_prot_sg = NULL;
2181                 cmd->t_prot_nents = 0;
2182         }
2183
2184         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2185                 /*
2186                  * Release special case READ buffer payload required for
2187                  * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2188                  */
2189                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2190                         transport_free_sgl(cmd->t_bidi_data_sg,
2191                                            cmd->t_bidi_data_nents);
2192                         cmd->t_bidi_data_sg = NULL;
2193                         cmd->t_bidi_data_nents = 0;
2194                 }
2195                 transport_reset_sgl_orig(cmd);
2196                 return;
2197         }
2198         transport_reset_sgl_orig(cmd);
2199
2200         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2201         cmd->t_data_sg = NULL;
2202         cmd->t_data_nents = 0;
2203
2204         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2205         cmd->t_bidi_data_sg = NULL;
2206         cmd->t_bidi_data_nents = 0;
2207 }
2208
2209 /**
2210  * transport_release_cmd - free a command
2211  * @cmd:       command to free
2212  *
2213  * This routine unconditionally frees a command, and reference counting
2214  * or list removal must be done in the caller.
2215  */
2216 static int transport_release_cmd(struct se_cmd *cmd)
2217 {
2218         BUG_ON(!cmd->se_tfo);
2219
2220         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2221                 core_tmr_release_req(cmd->se_tmr_req);
2222         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2223                 kfree(cmd->t_task_cdb);
2224         /*
2225          * If this cmd has been setup with target_get_sess_cmd(), drop
2226          * the kref and call ->release_cmd() in kref callback.
2227          */
2228         return target_put_sess_cmd(cmd);
2229 }
2230
2231 /**
2232  * transport_put_cmd - release a reference to a command
2233  * @cmd:       command to release
2234  *
2235  * This routine releases our reference to the command and frees it if possible.
2236  */
2237 static int transport_put_cmd(struct se_cmd *cmd)
2238 {
2239         transport_free_pages(cmd);
2240         return transport_release_cmd(cmd);
2241 }
2242
2243 void *transport_kmap_data_sg(struct se_cmd *cmd)
2244 {
2245         struct scatterlist *sg = cmd->t_data_sg;
2246         struct page **pages;
2247         int i;
2248
2249         /*
2250          * We need to take into account a possible offset here for fabrics like
2251          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2252          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2253          */
2254         if (!cmd->t_data_nents)
2255                 return NULL;
2256
2257         BUG_ON(!sg);
2258         if (cmd->t_data_nents == 1)
2259                 return kmap(sg_page(sg)) + sg->offset;
2260
2261         /* >1 page. use vmap */
2262         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2263         if (!pages)
2264                 return NULL;
2265
2266         /* convert sg[] to pages[] */
2267         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2268                 pages[i] = sg_page(sg);
2269         }
2270
2271         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2272         kfree(pages);
2273         if (!cmd->t_data_vmap)
2274                 return NULL;
2275
2276         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2277 }
2278 EXPORT_SYMBOL(transport_kmap_data_sg);
2279
2280 void transport_kunmap_data_sg(struct se_cmd *cmd)
2281 {
2282         if (!cmd->t_data_nents) {
2283                 return;
2284         } else if (cmd->t_data_nents == 1) {
2285                 kunmap(sg_page(cmd->t_data_sg));
2286                 return;
2287         }
2288
2289         vunmap(cmd->t_data_vmap);
2290         cmd->t_data_vmap = NULL;
2291 }
2292 EXPORT_SYMBOL(transport_kunmap_data_sg);
2293
2294 int
2295 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2296                  bool zero_page)
2297 {
2298         struct scatterlist *sg;
2299         struct page *page;
2300         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2301         unsigned int nent;
2302         int i = 0;
2303
2304         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2305         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2306         if (!sg)
2307                 return -ENOMEM;
2308
2309         sg_init_table(sg, nent);
2310
2311         while (length) {
2312                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2313                 page = alloc_page(GFP_KERNEL | zero_flag);
2314                 if (!page)
2315                         goto out;
2316
2317                 sg_set_page(&sg[i], page, page_len, 0);
2318                 length -= page_len;
2319                 i++;
2320         }
2321         *sgl = sg;
2322         *nents = nent;
2323         return 0;
2324
2325 out:
2326         while (i > 0) {
2327                 i--;
2328                 __free_page(sg_page(&sg[i]));
2329         }
2330         kfree(sg);
2331         return -ENOMEM;
2332 }
2333
2334 /*
2335  * Allocate any required resources to execute the command.  For writes we
2336  * might not have the payload yet, so notify the fabric via a call to
2337  * ->write_pending instead. Otherwise place it on the execution queue.
2338  */
2339 sense_reason_t
2340 transport_generic_new_cmd(struct se_cmd *cmd)
2341 {
2342         int ret = 0;
2343         bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2344
2345         if (cmd->prot_op != TARGET_PROT_NORMAL &&
2346             !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2347                 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2348                                        cmd->prot_length, true);
2349                 if (ret < 0)
2350                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2351         }
2352
2353         /*
2354          * Determine is the TCM fabric module has already allocated physical
2355          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2356          * beforehand.
2357          */
2358         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2359             cmd->data_length) {
2360
2361                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2362                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2363                         u32 bidi_length;
2364
2365                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2366                                 bidi_length = cmd->t_task_nolb *
2367                                               cmd->se_dev->dev_attrib.block_size;
2368                         else
2369                                 bidi_length = cmd->data_length;
2370
2371                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2372                                                &cmd->t_bidi_data_nents,
2373                                                bidi_length, zero_flag);
2374                         if (ret < 0)
2375                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2376                 }
2377
2378                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2379                                        cmd->data_length, zero_flag);
2380                 if (ret < 0)
2381                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2382         } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2383                     cmd->data_length) {
2384                 /*
2385                  * Special case for COMPARE_AND_WRITE with fabrics
2386                  * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2387                  */
2388                 u32 caw_length = cmd->t_task_nolb *
2389                                  cmd->se_dev->dev_attrib.block_size;
2390
2391                 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2392                                        &cmd->t_bidi_data_nents,
2393                                        caw_length, zero_flag);
2394                 if (ret < 0)
2395                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2396         }
2397         /*
2398          * If this command is not a write we can execute it right here,
2399          * for write buffers we need to notify the fabric driver first
2400          * and let it call back once the write buffers are ready.
2401          */
2402         target_add_to_state_list(cmd);
2403         if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2404                 target_execute_cmd(cmd);
2405                 return 0;
2406         }
2407         transport_cmd_check_stop(cmd, false, true);
2408
2409         ret = cmd->se_tfo->write_pending(cmd);
2410         if (ret == -EAGAIN || ret == -ENOMEM)
2411                 goto queue_full;
2412
2413         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2414         WARN_ON(ret);
2415
2416         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2417
2418 queue_full:
2419         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2420         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2421         transport_handle_queue_full(cmd, cmd->se_dev);
2422         return 0;
2423 }
2424 EXPORT_SYMBOL(transport_generic_new_cmd);
2425
2426 static void transport_write_pending_qf(struct se_cmd *cmd)
2427 {
2428         int ret;
2429
2430         ret = cmd->se_tfo->write_pending(cmd);
2431         if (ret == -EAGAIN || ret == -ENOMEM) {
2432                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2433                          cmd);
2434                 transport_handle_queue_full(cmd, cmd->se_dev);
2435         }
2436 }
2437
2438 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2439 {
2440         unsigned long flags;
2441         int ret = 0;
2442
2443         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2444                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2445                          transport_wait_for_tasks(cmd);
2446
2447                 ret = transport_release_cmd(cmd);
2448         } else {
2449                 if (wait_for_tasks)
2450                         transport_wait_for_tasks(cmd);
2451                 /*
2452                  * Handle WRITE failure case where transport_generic_new_cmd()
2453                  * has already added se_cmd to state_list, but fabric has
2454                  * failed command before I/O submission.
2455                  */
2456                 if (cmd->state_active) {
2457                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2458                         target_remove_from_state_list(cmd);
2459                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2460                 }
2461
2462                 if (cmd->se_lun)
2463                         transport_lun_remove_cmd(cmd);
2464
2465                 ret = transport_put_cmd(cmd);
2466         }
2467         return ret;
2468 }
2469 EXPORT_SYMBOL(transport_generic_free_cmd);
2470
2471 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2472  * @se_cmd:     command descriptor to add
2473  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2474  */
2475 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2476 {
2477         struct se_session *se_sess = se_cmd->se_sess;
2478         unsigned long flags;
2479         int ret = 0;
2480
2481         /*
2482          * Add a second kref if the fabric caller is expecting to handle
2483          * fabric acknowledgement that requires two target_put_sess_cmd()
2484          * invocations before se_cmd descriptor release.
2485          */
2486         if (ack_kref)
2487                 kref_get(&se_cmd->cmd_kref);
2488
2489         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2490         if (se_sess->sess_tearing_down) {
2491                 ret = -ESHUTDOWN;
2492                 goto out;
2493         }
2494         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2495 out:
2496         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2497
2498         if (ret && ack_kref)
2499                 target_put_sess_cmd(se_cmd);
2500
2501         return ret;
2502 }
2503 EXPORT_SYMBOL(target_get_sess_cmd);
2504
2505 static void target_release_cmd_kref(struct kref *kref)
2506                 __releases(&se_cmd->se_sess->sess_cmd_lock)
2507 {
2508         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2509         struct se_session *se_sess = se_cmd->se_sess;
2510
2511         if (list_empty(&se_cmd->se_cmd_list)) {
2512                 spin_unlock(&se_sess->sess_cmd_lock);
2513                 se_cmd->se_tfo->release_cmd(se_cmd);
2514                 return;
2515         }
2516         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2517                 spin_unlock(&se_sess->sess_cmd_lock);
2518                 complete(&se_cmd->cmd_wait_comp);
2519                 return;
2520         }
2521         list_del(&se_cmd->se_cmd_list);
2522         spin_unlock(&se_sess->sess_cmd_lock);
2523
2524         se_cmd->se_tfo->release_cmd(se_cmd);
2525 }
2526
2527 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2528  * @se_cmd:     command descriptor to drop
2529  */
2530 int target_put_sess_cmd(struct se_cmd *se_cmd)
2531 {
2532         struct se_session *se_sess = se_cmd->se_sess;
2533
2534         if (!se_sess) {
2535                 se_cmd->se_tfo->release_cmd(se_cmd);
2536                 return 1;
2537         }
2538         return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2539                         &se_sess->sess_cmd_lock);
2540 }
2541 EXPORT_SYMBOL(target_put_sess_cmd);
2542
2543 /* target_sess_cmd_list_set_waiting - Flag all commands in
2544  *         sess_cmd_list to complete cmd_wait_comp.  Set
2545  *         sess_tearing_down so no more commands are queued.
2546  * @se_sess:    session to flag
2547  */
2548 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2549 {
2550         struct se_cmd *se_cmd;
2551         unsigned long flags;
2552
2553         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2554         if (se_sess->sess_tearing_down) {
2555                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2556                 return;
2557         }
2558         se_sess->sess_tearing_down = 1;
2559         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2560
2561         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2562                 se_cmd->cmd_wait_set = 1;
2563
2564         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2565 }
2566 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2567
2568 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2569  * @se_sess:    session to wait for active I/O
2570  */
2571 void target_wait_for_sess_cmds(struct se_session *se_sess)
2572 {
2573         struct se_cmd *se_cmd, *tmp_cmd;
2574         unsigned long flags;
2575
2576         list_for_each_entry_safe(se_cmd, tmp_cmd,
2577                                 &se_sess->sess_wait_list, se_cmd_list) {
2578                 list_del(&se_cmd->se_cmd_list);
2579
2580                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2581                         " %d\n", se_cmd, se_cmd->t_state,
2582                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2583
2584                 wait_for_completion(&se_cmd->cmd_wait_comp);
2585                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2586                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2587                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2588
2589                 se_cmd->se_tfo->release_cmd(se_cmd);
2590         }
2591
2592         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2593         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2594         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2595
2596 }
2597 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2598
2599 static int transport_clear_lun_ref_thread(void *p)
2600 {
2601         struct se_lun *lun = p;
2602
2603         percpu_ref_kill(&lun->lun_ref);
2604
2605         wait_for_completion(&lun->lun_ref_comp);
2606         complete(&lun->lun_shutdown_comp);
2607
2608         return 0;
2609 }
2610
2611 int transport_clear_lun_ref(struct se_lun *lun)
2612 {
2613         struct task_struct *kt;
2614
2615         kt = kthread_run(transport_clear_lun_ref_thread, lun,
2616                         "tcm_cl_%u", lun->unpacked_lun);
2617         if (IS_ERR(kt)) {
2618                 pr_err("Unable to start clear_lun thread\n");
2619                 return PTR_ERR(kt);
2620         }
2621         wait_for_completion(&lun->lun_shutdown_comp);
2622
2623         return 0;
2624 }
2625
2626 /**
2627  * transport_wait_for_tasks - wait for completion to occur
2628  * @cmd:        command to wait
2629  *
2630  * Called from frontend fabric context to wait for storage engine
2631  * to pause and/or release frontend generated struct se_cmd.
2632  */
2633 bool transport_wait_for_tasks(struct se_cmd *cmd)
2634 {
2635         unsigned long flags;
2636
2637         spin_lock_irqsave(&cmd->t_state_lock, flags);
2638         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2639             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2640                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2641                 return false;
2642         }
2643
2644         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2645             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2646                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2647                 return false;
2648         }
2649
2650         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2651                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2652                 return false;
2653         }
2654
2655         cmd->transport_state |= CMD_T_STOP;
2656
2657         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08llx i_state: %d, t_state: %d, CMD_T_STOP\n",
2658                 cmd, cmd->tag, cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2659
2660         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2661
2662         wait_for_completion(&cmd->t_transport_stop_comp);
2663
2664         spin_lock_irqsave(&cmd->t_state_lock, flags);
2665         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2666
2667         pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->t_transport_stop_comp) for ITT: 0x%08llx\n",
2668                 cmd->tag);
2669
2670         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2671
2672         return true;
2673 }
2674 EXPORT_SYMBOL(transport_wait_for_tasks);
2675
2676 static int transport_get_sense_codes(
2677         struct se_cmd *cmd,
2678         u8 *asc,
2679         u8 *ascq)
2680 {
2681         *asc = cmd->scsi_asc;
2682         *ascq = cmd->scsi_ascq;
2683
2684         return 0;
2685 }
2686
2687 static
2688 void transport_err_sector_info(unsigned char *buffer, sector_t bad_sector)
2689 {
2690         /* Place failed LBA in sense data information descriptor 0. */
2691         buffer[SPC_ADD_SENSE_LEN_OFFSET] = 0xc;
2692         buffer[SPC_DESC_TYPE_OFFSET] = 0; /* Information */
2693         buffer[SPC_ADDITIONAL_DESC_LEN_OFFSET] = 0xa;
2694         buffer[SPC_VALIDITY_OFFSET] = 0x80;
2695
2696         /* Descriptor Information: failing sector */
2697         put_unaligned_be64(bad_sector, &buffer[12]);
2698 }
2699
2700 int
2701 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2702                 sense_reason_t reason, int from_transport)
2703 {
2704         unsigned char *buffer = cmd->sense_buffer;
2705         unsigned long flags;
2706         u8 asc = 0, ascq = 0;
2707
2708         spin_lock_irqsave(&cmd->t_state_lock, flags);
2709         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2710                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2711                 return 0;
2712         }
2713         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2714         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2715
2716         if (!reason && from_transport)
2717                 goto after_reason;
2718
2719         if (!from_transport)
2720                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2721
2722         /*
2723          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2724          * SENSE KEY values from include/scsi/scsi.h
2725          */
2726         switch (reason) {
2727         case TCM_NO_SENSE:
2728                 /* CURRENT ERROR */
2729                 buffer[0] = 0x70;
2730                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2731                 /* Not Ready */
2732                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2733                 /* NO ADDITIONAL SENSE INFORMATION */
2734                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2735                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2736                 break;
2737         case TCM_NON_EXISTENT_LUN:
2738                 /* CURRENT ERROR */
2739                 buffer[0] = 0x70;
2740                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2741                 /* ILLEGAL REQUEST */
2742                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2743                 /* LOGICAL UNIT NOT SUPPORTED */
2744                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2745                 break;
2746         case TCM_UNSUPPORTED_SCSI_OPCODE:
2747         case TCM_SECTOR_COUNT_TOO_MANY:
2748                 /* CURRENT ERROR */
2749                 buffer[0] = 0x70;
2750                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2751                 /* ILLEGAL REQUEST */
2752                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2753                 /* INVALID COMMAND OPERATION CODE */
2754                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2755                 break;
2756         case TCM_UNKNOWN_MODE_PAGE:
2757                 /* CURRENT ERROR */
2758                 buffer[0] = 0x70;
2759                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2760                 /* ILLEGAL REQUEST */
2761                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2762                 /* INVALID FIELD IN CDB */
2763                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2764                 break;
2765         case TCM_CHECK_CONDITION_ABORT_CMD:
2766                 /* CURRENT ERROR */
2767                 buffer[0] = 0x70;
2768                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2769                 /* ABORTED COMMAND */
2770                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2771                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2772                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2773                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2774                 break;
2775         case TCM_INCORRECT_AMOUNT_OF_DATA:
2776                 /* CURRENT ERROR */
2777                 buffer[0] = 0x70;
2778                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2779                 /* ABORTED COMMAND */
2780                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2781                 /* WRITE ERROR */
2782                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2783                 /* NOT ENOUGH UNSOLICITED DATA */
2784                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2785                 break;
2786         case TCM_INVALID_CDB_FIELD:
2787                 /* CURRENT ERROR */
2788                 buffer[0] = 0x70;
2789                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2790                 /* ILLEGAL REQUEST */
2791                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2792                 /* INVALID FIELD IN CDB */
2793                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2794                 break;
2795         case TCM_INVALID_PARAMETER_LIST:
2796                 /* CURRENT ERROR */
2797                 buffer[0] = 0x70;
2798                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2799                 /* ILLEGAL REQUEST */
2800                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2801                 /* INVALID FIELD IN PARAMETER LIST */
2802                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2803                 break;
2804         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2805                 /* CURRENT ERROR */
2806                 buffer[0] = 0x70;
2807                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2808                 /* ILLEGAL REQUEST */
2809                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2810                 /* PARAMETER LIST LENGTH ERROR */
2811                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2812                 break;
2813         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2814                 /* CURRENT ERROR */
2815                 buffer[0] = 0x70;
2816                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2817                 /* ABORTED COMMAND */
2818                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2819                 /* WRITE ERROR */
2820                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2821                 /* UNEXPECTED_UNSOLICITED_DATA */
2822                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2823                 break;
2824         case TCM_SERVICE_CRC_ERROR:
2825                 /* CURRENT ERROR */
2826                 buffer[0] = 0x70;
2827                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2828                 /* ABORTED COMMAND */
2829                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2830                 /* PROTOCOL SERVICE CRC ERROR */
2831                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2832                 /* N/A */
2833                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2834                 break;
2835         case TCM_SNACK_REJECTED:
2836                 /* CURRENT ERROR */
2837                 buffer[0] = 0x70;
2838                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2839                 /* ABORTED COMMAND */
2840                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2841                 /* READ ERROR */
2842                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2843                 /* FAILED RETRANSMISSION REQUEST */
2844                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2845                 break;
2846         case TCM_WRITE_PROTECTED:
2847                 /* CURRENT ERROR */
2848                 buffer[0] = 0x70;
2849                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2850                 /* DATA PROTECT */
2851                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2852                 /* WRITE PROTECTED */
2853                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2854                 break;
2855         case TCM_ADDRESS_OUT_OF_RANGE:
2856                 /* CURRENT ERROR */
2857                 buffer[0] = 0x70;
2858                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2859                 /* ILLEGAL REQUEST */
2860                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2861                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2862                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2863                 break;
2864         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2865                 /* CURRENT ERROR */
2866                 buffer[0] = 0x70;
2867                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2868                 /* UNIT ATTENTION */
2869                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2870                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2871                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2872                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2873                 break;
2874         case TCM_CHECK_CONDITION_NOT_READY:
2875                 /* CURRENT ERROR */
2876                 buffer[0] = 0x70;
2877                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2878                 /* Not Ready */
2879                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2880                 transport_get_sense_codes(cmd, &asc, &ascq);
2881                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2882                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2883                 break;
2884         case TCM_MISCOMPARE_VERIFY:
2885                 /* CURRENT ERROR */
2886                 buffer[0] = 0x70;
2887                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2888                 buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
2889                 /* MISCOMPARE DURING VERIFY OPERATION */
2890                 buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
2891                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
2892                 break;
2893         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
2894                 /* CURRENT ERROR */
2895                 buffer[0] = 0x70;
2896                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2897                 /* ILLEGAL REQUEST */
2898                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2899                 /* LOGICAL BLOCK GUARD CHECK FAILED */
2900                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2901                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x01;
2902                 transport_err_sector_info(buffer, cmd->bad_sector);
2903                 break;
2904         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
2905                 /* CURRENT ERROR */
2906                 buffer[0] = 0x70;
2907                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2908                 /* ILLEGAL REQUEST */
2909                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2910                 /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2911                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2912                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x02;
2913                 transport_err_sector_info(buffer, cmd->bad_sector);
2914                 break;
2915         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
2916                 /* CURRENT ERROR */
2917                 buffer[0] = 0x70;
2918                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2919                 /* ILLEGAL REQUEST */
2920                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2921                 /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2922                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2923                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2924                 transport_err_sector_info(buffer, cmd->bad_sector);
2925                 break;
2926         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2927         default:
2928                 /* CURRENT ERROR */
2929                 buffer[0] = 0x70;
2930                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2931                 /*
2932                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2933                  * Solaris initiators.  Returning NOT READY instead means the
2934                  * operations will be retried a finite number of times and we
2935                  * can survive intermittent errors.
2936                  */
2937                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2938                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2939                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2940                 break;
2941         }
2942         /*
2943          * This code uses linux/include/scsi/scsi.h SAM status codes!
2944          */
2945         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2946         /*
2947          * Automatically padded, this value is encoded in the fabric's
2948          * data_length response PDU containing the SCSI defined sense data.
2949          */
2950         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2951
2952 after_reason:
2953         trace_target_cmd_complete(cmd);
2954         return cmd->se_tfo->queue_status(cmd);
2955 }
2956 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2957
2958 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2959 {
2960         if (!(cmd->transport_state & CMD_T_ABORTED))
2961                 return 0;
2962
2963         /*
2964          * If cmd has been aborted but either no status is to be sent or it has
2965          * already been sent, just return
2966          */
2967         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
2968                 return 1;
2969
2970         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08llx\n",
2971                  cmd->t_task_cdb[0], cmd->tag);
2972
2973         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2974         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2975         trace_target_cmd_complete(cmd);
2976         cmd->se_tfo->queue_status(cmd);
2977
2978         return 1;
2979 }
2980 EXPORT_SYMBOL(transport_check_aborted_status);
2981
2982 void transport_send_task_abort(struct se_cmd *cmd)
2983 {
2984         unsigned long flags;
2985
2986         spin_lock_irqsave(&cmd->t_state_lock, flags);
2987         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2988                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2989                 return;
2990         }
2991         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2992
2993         /*
2994          * If there are still expected incoming fabric WRITEs, we wait
2995          * until until they have completed before sending a TASK_ABORTED
2996          * response.  This response with TASK_ABORTED status will be
2997          * queued back to fabric module by transport_check_aborted_status().
2998          */
2999         if (cmd->data_direction == DMA_TO_DEVICE) {
3000                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
3001                         cmd->transport_state |= CMD_T_ABORTED;
3002                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3003                         return;
3004                 }
3005         }
3006         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3007
3008         transport_lun_remove_cmd(cmd);
3009
3010         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
3011                  cmd->t_task_cdb[0], cmd->tag);
3012
3013         trace_target_cmd_complete(cmd);
3014         cmd->se_tfo->queue_status(cmd);
3015 }
3016
3017 static void target_tmr_work(struct work_struct *work)
3018 {
3019         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3020         struct se_device *dev = cmd->se_dev;
3021         struct se_tmr_req *tmr = cmd->se_tmr_req;
3022         int ret;
3023
3024         switch (tmr->function) {
3025         case TMR_ABORT_TASK:
3026                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3027                 break;
3028         case TMR_ABORT_TASK_SET:
3029         case TMR_CLEAR_ACA:
3030         case TMR_CLEAR_TASK_SET:
3031                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3032                 break;
3033         case TMR_LUN_RESET:
3034                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3035                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3036                                          TMR_FUNCTION_REJECTED;
3037                 break;
3038         case TMR_TARGET_WARM_RESET:
3039                 tmr->response = TMR_FUNCTION_REJECTED;
3040                 break;
3041         case TMR_TARGET_COLD_RESET:
3042                 tmr->response = TMR_FUNCTION_REJECTED;
3043                 break;
3044         default:
3045                 pr_err("Uknown TMR function: 0x%02x.\n",
3046                                 tmr->function);
3047                 tmr->response = TMR_FUNCTION_REJECTED;
3048                 break;
3049         }
3050
3051         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3052         cmd->se_tfo->queue_tm_rsp(cmd);
3053
3054         transport_cmd_check_stop_to_fabric(cmd);
3055 }
3056
3057 int transport_generic_handle_tmr(
3058         struct se_cmd *cmd)
3059 {
3060         unsigned long flags;
3061
3062         spin_lock_irqsave(&cmd->t_state_lock, flags);
3063         cmd->transport_state |= CMD_T_ACTIVE;
3064         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3065
3066         INIT_WORK(&cmd->work, target_tmr_work);
3067         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3068         return 0;
3069 }
3070 EXPORT_SYMBOL(transport_generic_handle_tmr);
3071
3072 bool
3073 target_check_wce(struct se_device *dev)
3074 {
3075         bool wce = false;
3076
3077         if (dev->transport->get_write_cache)
3078                 wce = dev->transport->get_write_cache(dev);
3079         else if (dev->dev_attrib.emulate_write_cache > 0)
3080                 wce = true;
3081
3082         return wce;
3083 }
3084
3085 bool
3086 target_check_fua(struct se_device *dev)
3087 {
3088         return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3089 }