drivers/target/target_core_transport.c

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