drivers/target/target_core_transport.c

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