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