drivers/target/target_core_transport.c

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