kernel/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 #include <scsi/scsi_common.h>
  43
  44 #include <target/target_core_base.h>
  45 #include <target/target_core_backend.h>
  46 #include <target/target_core_fabric.h>
  47
  48 #include "target_core_internal.h"
  49 #include "target_core_alua.h"
  50 #include "target_core_pr.h"
  51 #include "target_core_ua.h"
  52
  53 #define CREATE_TRACE_POINTS
  54 #include <trace/events/target.h>
  55
  56 static struct workqueue_struct *target_completion_wq;
  57 static struct kmem_cache *se_sess_cache;
  58 struct kmem_cache *se_ua_cache;
  59 struct kmem_cache *t10_pr_reg_cache;
  60 struct kmem_cache *t10_alua_lu_gp_cache;
  61 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  62 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  63 struct kmem_cache *t10_alua_lba_map_cache;
  64 struct kmem_cache *t10_alua_lba_map_mem_cache;
  65
  66 static void transport_complete_task_attr(struct se_cmd *cmd);
  67 static void transport_handle_queue_full(struct se_cmd *cmd,
  68                 struct se_device *dev);
  69 static int transport_put_cmd(struct se_cmd *cmd);
  70 static void target_complete_ok_work(struct work_struct *work);
  71
  72 int init_se_kmem_caches(void)
  73 {
  74         se_sess_cache = kmem_cache_create("se_sess_cache",
  75                         sizeof(struct se_session), __alignof__(struct se_session),
  76                         0, NULL);
  77         if (!se_sess_cache) {
  78                 pr_err("kmem_cache_create() for struct se_session"
  79                                 " failed\n");
  80                 goto out;
  81         }
  82         se_ua_cache = kmem_cache_create("se_ua_cache",
  83                         sizeof(struct se_ua), __alignof__(struct se_ua),
  84                         0, NULL);
  85         if (!se_ua_cache) {
  86                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  87                 goto out_free_sess_cache;
  88         }
  89         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  90                         sizeof(struct t10_pr_registration),
  91                         __alignof__(struct t10_pr_registration), 0, NULL);
  92         if (!t10_pr_reg_cache) {
  93                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  94                                 " failed\n");
  95                 goto out_free_ua_cache;
  96         }
  97         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
  98                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
  99                         0, NULL);
 100         if (!t10_alua_lu_gp_cache) {
 101                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 102                                 " failed\n");
 103                 goto out_free_pr_reg_cache;
 104         }
 105         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 106                         sizeof(struct t10_alua_lu_gp_member),
 107                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 108         if (!t10_alua_lu_gp_mem_cache) {
 109                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 110                                 "cache failed\n");
 111                 goto out_free_lu_gp_cache;
 112         }
 113         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 114                         sizeof(struct t10_alua_tg_pt_gp),
 115                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 116         if (!t10_alua_tg_pt_gp_cache) {
 117                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 118                                 "cache failed\n");
 119                 goto out_free_lu_gp_mem_cache;
 120         }
 121         t10_alua_lba_map_cache = kmem_cache_create(
 122                         "t10_alua_lba_map_cache",
 123                         sizeof(struct t10_alua_lba_map),
 124                         __alignof__(struct t10_alua_lba_map), 0, NULL);
 125         if (!t10_alua_lba_map_cache) {
 126                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
 127                                 "cache failed\n");
 128                 goto out_free_tg_pt_gp_cache;
 129         }
 130         t10_alua_lba_map_mem_cache = kmem_cache_create(
 131                         "t10_alua_lba_map_mem_cache",
 132                         sizeof(struct t10_alua_lba_map_member),
 133                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
 134         if (!t10_alua_lba_map_mem_cache) {
 135                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
 136                                 "cache failed\n");
 137                 goto out_free_lba_map_cache;
 138         }
 139
 140         target_completion_wq = alloc_workqueue("target_completion",
 141                                                WQ_MEM_RECLAIM, 0);
 142         if (!target_completion_wq)
 143                 goto out_free_lba_map_mem_cache;
 144
 145         return 0;
 146
 147 out_free_lba_map_mem_cache:
 148         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 149 out_free_lba_map_cache:
 150         kmem_cache_destroy(t10_alua_lba_map_cache);
 151 out_free_tg_pt_gp_cache:
 152         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 153 out_free_lu_gp_mem_cache:
 154         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 155 out_free_lu_gp_cache:
 156         kmem_cache_destroy(t10_alua_lu_gp_cache);
 157 out_free_pr_reg_cache:
 158         kmem_cache_destroy(t10_pr_reg_cache);
 159 out_free_ua_cache:
 160         kmem_cache_destroy(se_ua_cache);
 161 out_free_sess_cache:
 162         kmem_cache_destroy(se_sess_cache);
 163 out:
 164         return -ENOMEM;
 165 }
 166
 167 void release_se_kmem_caches(void)
 168 {
 169         destroy_workqueue(target_completion_wq);
 170         kmem_cache_destroy(se_sess_cache);
 171         kmem_cache_destroy(se_ua_cache);
 172         kmem_cache_destroy(t10_pr_reg_cache);
 173         kmem_cache_destroy(t10_alua_lu_gp_cache);
 174         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 175         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 176         kmem_cache_destroy(t10_alua_lba_map_cache);
 177         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 178 }
 179
 180 /* This code ensures unique mib indexes are handed out. */
 181 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 182 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 183
 184 /*
 185  * Allocate a new row index for the entry type specified
 186  */
 187 u32 scsi_get_new_index(scsi_index_t type)
 188 {
 189         u32 new_index;
 190
 191         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 192
 193         spin_lock(&scsi_mib_index_lock);
 194         new_index = ++scsi_mib_index[type];
 195         spin_unlock(&scsi_mib_index_lock);
 196
 197         return new_index;
 198 }
 199
 200 void transport_subsystem_check_init(void)
 201 {
 202         int ret;
 203         static int sub_api_initialized;
 204
 205         if (sub_api_initialized)
 206                 return;
 207
 208         ret = request_module("target_core_iblock");
 209         if (ret != 0)
 210                 pr_err("Unable to load target_core_iblock\n");
 211
 212         ret = request_module("target_core_file");
 213         if (ret != 0)
 214                 pr_err("Unable to load target_core_file\n");
 215
 216         ret = request_module("target_core_pscsi");
 217         if (ret != 0)
 218                 pr_err("Unable to load target_core_pscsi\n");
 219
 220         ret = request_module("target_core_user");
 221         if (ret != 0)
 222                 pr_err("Unable to load target_core_user\n");
 223
 224         sub_api_initialized = 1;
 225 }
 226
 227 struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
 228 {
 229         struct se_session *se_sess;
 230
 231         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 232         if (!se_sess) {
 233                 pr_err("Unable to allocate struct se_session from"
 234                                 " se_sess_cache\n");
 235                 return ERR_PTR(-ENOMEM);
 236         }
 237         INIT_LIST_HEAD(&se_sess->sess_list);
 238         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 239         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 240         INIT_LIST_HEAD(&se_sess->sess_wait_list);
 241         spin_lock_init(&se_sess->sess_cmd_lock);
 242         kref_init(&se_sess->sess_kref);
 243         se_sess->sup_prot_ops = sup_prot_ops;
 244
 245         return se_sess;
 246 }
 247 EXPORT_SYMBOL(transport_init_session);
 248
 249 int transport_alloc_session_tags(struct se_session *se_sess,
 250                                  unsigned int tag_num, unsigned int tag_size)
 251 {
 252         int rc;
 253
 254         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
 255                                         GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
 256         if (!se_sess->sess_cmd_map) {
 257                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
 258                 if (!se_sess->sess_cmd_map) {
 259                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 260                         return -ENOMEM;
 261                 }
 262         }
 263
 264         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
 265         if (rc < 0) {
 266                 pr_err("Unable to init se_sess->sess_tag_pool,"
 267                         " tag_num: %u\n", tag_num);
 268                 kvfree(se_sess->sess_cmd_map);
 269                 se_sess->sess_cmd_map = NULL;
 270                 return -ENOMEM;
 271         }
 272
 273         return 0;
 274 }
 275 EXPORT_SYMBOL(transport_alloc_session_tags);
 276
 277 struct se_session *transport_init_session_tags(unsigned int tag_num,
 278                                                unsigned int tag_size,
 279                                                enum target_prot_op sup_prot_ops)
 280 {
 281         struct se_session *se_sess;
 282         int rc;
 283
 284         se_sess = transport_init_session(sup_prot_ops);
 285         if (IS_ERR(se_sess))
 286                 return se_sess;
 287
 288         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 289         if (rc < 0) {
 290                 transport_free_session(se_sess);
 291                 return ERR_PTR(-ENOMEM);
 292         }
 293
 294         return se_sess;
 295 }
 296 EXPORT_SYMBOL(transport_init_session_tags);
 297
 298 /*
 299  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 300  */
 301 void __transport_register_session(
 302         struct se_portal_group *se_tpg,
 303         struct se_node_acl *se_nacl,
 304         struct se_session *se_sess,
 305         void *fabric_sess_ptr)
 306 {
 307         const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
 308         unsigned char buf[PR_REG_ISID_LEN];
 309
 310         se_sess->se_tpg = se_tpg;
 311         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 312         /*
 313          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 314          *
 315          * Only set for struct se_session's that will actually be moving I/O.
 316          * eg: *NOT* discovery sessions.
 317          */
 318         if (se_nacl) {
 319                 /*
 320                  *
 321                  * Determine if fabric allows for T10-PI feature bits exposed to
 322                  * initiators for device backends with !dev->dev_attrib.pi_prot_type.
 323                  *
 324                  * If so, then always save prot_type on a per se_node_acl node
 325                  * basis and re-instate the previous sess_prot_type to avoid
 326                  * disabling PI from below any previously initiator side
 327                  * registered LUNs.
 328                  */
 329                 if (se_nacl->saved_prot_type)
 330                         se_sess->sess_prot_type = se_nacl->saved_prot_type;
 331                 else if (tfo->tpg_check_prot_fabric_only)
 332                         se_sess->sess_prot_type = se_nacl->saved_prot_type =
 333                                         tfo->tpg_check_prot_fabric_only(se_tpg);
 334                 /*
 335                  * If the fabric module supports an ISID based TransportID,
 336                  * save this value in binary from the fabric I_T Nexus now.
 337                  */
 338                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 339                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 340                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 341                                         &buf[0], PR_REG_ISID_LEN);
 342                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 343                 }
 344                 kref_get(&se_nacl->acl_kref);
 345
 346                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 347                 /*
 348                  * The se_nacl->nacl_sess pointer will be set to the
 349                  * last active I_T Nexus for each struct se_node_acl.
 350                  */
 351                 se_nacl->nacl_sess = se_sess;
 352
 353                 list_add_tail(&se_sess->sess_acl_list,
 354                               &se_nacl->acl_sess_list);
 355                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 356         }
 357         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 358
 359         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 360                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 361 }
 362 EXPORT_SYMBOL(__transport_register_session);
 363
 364 void transport_register_session(
 365         struct se_portal_group *se_tpg,
 366         struct se_node_acl *se_nacl,
 367         struct se_session *se_sess,
 368         void *fabric_sess_ptr)
 369 {
 370         unsigned long flags;
 371
 372         spin_lock_irqsave(&se_tpg->session_lock, flags);
 373         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 374         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 375 }
 376 EXPORT_SYMBOL(transport_register_session);
 377
 378 static void target_release_session(struct kref *kref)
 379 {
 380         struct se_session *se_sess = container_of(kref,
 381                         struct se_session, sess_kref);
 382         struct se_portal_group *se_tpg = se_sess->se_tpg;
 383
 384         se_tpg->se_tpg_tfo->close_session(se_sess);
 385 }
 386
 387 void target_get_session(struct se_session *se_sess)
 388 {
 389         kref_get(&se_sess->sess_kref);
 390 }
 391 EXPORT_SYMBOL(target_get_session);
 392
 393 void target_put_session(struct se_session *se_sess)
 394 {
 395         kref_put(&se_sess->sess_kref, target_release_session);
 396 }
 397 EXPORT_SYMBOL(target_put_session);
 398
 399 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
 400 {
 401         struct se_session *se_sess;
 402         ssize_t len = 0;
 403
 404         spin_lock_bh(&se_tpg->session_lock);
 405         list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
 406                 if (!se_sess->se_node_acl)
 407                         continue;
 408                 if (!se_sess->se_node_acl->dynamic_node_acl)
 409                         continue;
 410                 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
 411                         break;
 412
 413                 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
 414                                 se_sess->se_node_acl->initiatorname);
 415                 len += 1; /* Include NULL terminator */
 416         }
 417         spin_unlock_bh(&se_tpg->session_lock);
 418
 419         return len;
 420 }
 421 EXPORT_SYMBOL(target_show_dynamic_sessions);
 422
 423 static void target_complete_nacl(struct kref *kref)
 424 {
 425         struct se_node_acl *nacl = container_of(kref,
 426                                 struct se_node_acl, acl_kref);
 427
 428         complete(&nacl->acl_free_comp);
 429 }
 430
 431 void target_put_nacl(struct se_node_acl *nacl)
 432 {
 433         kref_put(&nacl->acl_kref, target_complete_nacl);
 434 }
 435
 436 void transport_deregister_session_configfs(struct se_session *se_sess)
 437 {
 438         struct se_node_acl *se_nacl;
 439         unsigned long flags;
 440         /*
 441          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 442          */
 443         se_nacl = se_sess->se_node_acl;
 444         if (se_nacl) {
 445                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 446                 if (se_nacl->acl_stop == 0)
 447                         list_del(&se_sess->sess_acl_list);
 448                 /*
 449                  * If the session list is empty, then clear the pointer.
 450                  * Otherwise, set the struct se_session pointer from the tail
 451                  * element of the per struct se_node_acl active session list.
 452                  */
 453                 if (list_empty(&se_nacl->acl_sess_list))
 454                         se_nacl->nacl_sess = NULL;
 455                 else {
 456                         se_nacl->nacl_sess = container_of(
 457                                         se_nacl->acl_sess_list.prev,
 458                                         struct se_session, sess_acl_list);
 459                 }
 460                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 461         }
 462 }
 463 EXPORT_SYMBOL(transport_deregister_session_configfs);
 464
 465 void transport_free_session(struct se_session *se_sess)
 466 {
 467         if (se_sess->sess_cmd_map) {
 468                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 469                 kvfree(se_sess->sess_cmd_map);
 470         }
 471         kmem_cache_free(se_sess_cache, se_sess);
 472 }
 473 EXPORT_SYMBOL(transport_free_session);
 474
 475 void transport_deregister_session(struct se_session *se_sess)
 476 {
 477         struct se_portal_group *se_tpg = se_sess->se_tpg;
 478         const struct target_core_fabric_ops *se_tfo;
 479         struct se_node_acl *se_nacl;
 480         unsigned long flags;
 481         bool comp_nacl = true, drop_nacl = false;
 482
 483         if (!se_tpg) {
 484                 transport_free_session(se_sess);
 485                 return;
 486         }
 487         se_tfo = se_tpg->se_tpg_tfo;
 488
 489         spin_lock_irqsave(&se_tpg->session_lock, flags);
 490         list_del(&se_sess->sess_list);
 491         se_sess->se_tpg = NULL;
 492         se_sess->fabric_sess_ptr = NULL;
 493         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 494
 495         /*
 496          * Determine if we need to do extra work for this initiator node's
 497          * struct se_node_acl if it had been previously dynamically generated.
 498          */
 499         se_nacl = se_sess->se_node_acl;
 500
 501         mutex_lock(&se_tpg->acl_node_mutex);
 502         if (se_nacl && se_nacl->dynamic_node_acl) {
 503                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 504                         list_del(&se_nacl->acl_list);
 505                         se_tpg->num_node_acls--;
 506                         drop_nacl = true;
 507                 }
 508         }
 509         mutex_unlock(&se_tpg->acl_node_mutex);
 510
 511         if (drop_nacl) {
 512                 core_tpg_wait_for_nacl_pr_ref(se_nacl);
 513                 core_free_device_list_for_node(se_nacl, se_tpg);
 514                 kfree(se_nacl);
 515                 comp_nacl = false;
 516         }
 517         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 518                 se_tpg->se_tpg_tfo->get_fabric_name());
 519         /*
 520          * If last kref is dropping now for an explicit NodeACL, awake sleeping
 521          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 522          * removal context.
 523          */
 524         if (se_nacl && comp_nacl)
 525                 target_put_nacl(se_nacl);
 526
 527         transport_free_session(se_sess);
 528 }
 529 EXPORT_SYMBOL(transport_deregister_session);
 530
 531 static void target_remove_from_state_list(struct se_cmd *cmd)
 532 {
 533         struct se_device *dev = cmd->se_dev;
 534         unsigned long flags;
 535
 536         if (!dev)
 537                 return;
 538
 539         if (cmd->transport_state & CMD_T_BUSY)
 540                 return;
 541
 542         spin_lock_irqsave(&dev->execute_task_lock, flags);
 543         if (cmd->state_active) {
 544                 list_del(&cmd->state_list);
 545                 cmd->state_active = false;
 546         }
 547         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 548 }
 549
 550 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 551                                     bool write_pending)
 552 {
 553         unsigned long flags;
 554
 555         if (remove_from_lists) {
 556                 target_remove_from_state_list(cmd);
 557
 558                 /*
 559                  * Clear struct se_cmd->se_lun before the handoff to FE.
 560                  */
 561                 cmd->se_lun = NULL;
 562         }
 563
 564         spin_lock_irqsave(&cmd->t_state_lock, flags);
 565         if (write_pending)
 566                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 567
 568         /*
 569          * Determine if frontend context caller is requesting the stopping of
 570          * this command for frontend exceptions.
 571          */
 572         if (cmd->transport_state & CMD_T_STOP) {
 573                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
 574                         __func__, __LINE__, cmd->tag);
 575
 576                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 577
 578                 complete_all(&cmd->t_transport_stop_comp);
 579                 return 1;
 580         }
 581
 582         cmd->transport_state &= ~CMD_T_ACTIVE;
 583         if (remove_from_lists) {
 584                 /*
 585                  * Some fabric modules like tcm_loop can release
 586                  * their internally allocated I/O reference now and
 587                  * struct se_cmd now.
 588                  *
 589                  * Fabric modules are expected to return '1' here if the
 590                  * se_cmd being passed is released at this point,
 591                  * or zero if not being released.
 592                  */
 593                 if (cmd->se_tfo->check_stop_free != NULL) {
 594                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 595                         return cmd->se_tfo->check_stop_free(cmd);
 596                 }
 597         }
 598
 599         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 600         return 0;
 601 }
 602
 603 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 604 {
 605         return transport_cmd_check_stop(cmd, true, false);
 606 }
 607
 608 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 609 {
 610         struct se_lun *lun = cmd->se_lun;
 611
 612         if (!lun)
 613                 return;
 614
 615         if (cmpxchg(&cmd->lun_ref_active, true, false))
 616                 percpu_ref_put(&lun->lun_ref);
 617 }
 618
 619 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 620 {
 621         bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF);
 622
 623         if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
 624                 transport_lun_remove_cmd(cmd);
 625         /*
 626          * Allow the fabric driver to unmap any resources before
 627          * releasing the descriptor via TFO->release_cmd()
 628          */
 629         if (remove)
 630                 cmd->se_tfo->aborted_task(cmd);
 631
 632         if (transport_cmd_check_stop_to_fabric(cmd))
 633                 return;
 634         if (remove && ack_kref)
 635                 transport_put_cmd(cmd);
 636 }
 637
 638 static void target_complete_failure_work(struct work_struct *work)
 639 {
 640         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 641
 642         transport_generic_request_failure(cmd,
 643                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 644 }
 645
 646 /*
 647  * Used when asking transport to copy Sense Data from the underlying
 648  * Linux/SCSI struct scsi_cmnd
 649  */
 650 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 651 {
 652         struct se_device *dev = cmd->se_dev;
 653
 654         WARN_ON(!cmd->se_lun);
 655
 656         if (!dev)
 657                 return NULL;
 658
 659         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 660                 return NULL;
 661
 662         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 663
 664         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 665                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 666         return cmd->sense_buffer;
 667 }
 668
 669 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 670 {
 671         struct se_device *dev = cmd->se_dev;
 672         int success = scsi_status == GOOD;
 673         unsigned long flags;
 674
 675         cmd->scsi_status = scsi_status;
 676
 677
 678         spin_lock_irqsave(&cmd->t_state_lock, flags);
 679         cmd->transport_state &= ~CMD_T_BUSY;
 680
 681         if (dev && dev->transport->transport_complete) {
 682                 dev->transport->transport_complete(cmd,
 683                                 cmd->t_data_sg,
 684                                 transport_get_sense_buffer(cmd));
 685                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 686                         success = 1;
 687         }
 688
 689         /*
 690          * See if we are waiting to complete for an exception condition.
 691          */
 692         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
 693                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 694                 complete(&cmd->task_stop_comp);
 695                 return;
 696         }
 697
 698         /*
 699          * Check for case where an explicit ABORT_TASK has been received
 700          * and transport_wait_for_tasks() will be waiting for completion..
 701          */
 702         if (cmd->transport_state & CMD_T_ABORTED ||
 703             cmd->transport_state & CMD_T_STOP) {
 704                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 705                 complete_all(&cmd->t_transport_stop_comp);
 706                 return;
 707         } else if (!success) {
 708                 INIT_WORK(&cmd->work, target_complete_failure_work);
 709         } else {
 710                 INIT_WORK(&cmd->work, target_complete_ok_work);
 711         }
 712
 713         cmd->t_state = TRANSPORT_COMPLETE;
 714         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 715         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 716
 717         queue_work(target_completion_wq, &cmd->work);
 718 }
 719 EXPORT_SYMBOL(target_complete_cmd);
 720
 721 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 722 {
 723         if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
 724                 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 725                         cmd->residual_count += cmd->data_length - length;
 726                 } else {
 727                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
 728                         cmd->residual_count = cmd->data_length - length;
 729                 }
 730
 731                 cmd->data_length = length;
 732         }
 733
 734         target_complete_cmd(cmd, scsi_status);
 735 }
 736 EXPORT_SYMBOL(target_complete_cmd_with_length);
 737
 738 static void target_add_to_state_list(struct se_cmd *cmd)
 739 {
 740         struct se_device *dev = cmd->se_dev;
 741         unsigned long flags;
 742
 743         spin_lock_irqsave(&dev->execute_task_lock, flags);
 744         if (!cmd->state_active) {
 745                 list_add_tail(&cmd->state_list, &dev->state_list);
 746                 cmd->state_active = true;
 747         }
 748         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 749 }
 750
 751 /*
 752  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 753  */
 754 static void transport_write_pending_qf(struct se_cmd *cmd);
 755 static void transport_complete_qf(struct se_cmd *cmd);
 756
 757 void target_qf_do_work(struct work_struct *work)
 758 {
 759         struct se_device *dev = container_of(work, struct se_device,
 760                                         qf_work_queue);
 761         LIST_HEAD(qf_cmd_list);
 762         struct se_cmd *cmd, *cmd_tmp;
 763
 764         spin_lock_irq(&dev->qf_cmd_lock);
 765         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 766         spin_unlock_irq(&dev->qf_cmd_lock);
 767
 768         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 769                 list_del(&cmd->se_qf_node);
 770                 atomic_dec_mb(&dev->dev_qf_count);
 771
 772                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 773                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 774                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 775                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 776                         : "UNKNOWN");
 777
 778                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 779                         transport_write_pending_qf(cmd);
 780                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 781                         transport_complete_qf(cmd);
 782         }
 783 }
 784
 785 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 786 {
 787         switch (cmd->data_direction) {
 788         case DMA_NONE:
 789                 return "NONE";
 790         case DMA_FROM_DEVICE:
 791                 return "READ";
 792         case DMA_TO_DEVICE:
 793                 return "WRITE";
 794         case DMA_BIDIRECTIONAL:
 795                 return "BIDI";
 796         default:
 797                 break;
 798         }
 799
 800         return "UNKNOWN";
 801 }
 802
 803 void transport_dump_dev_state(
 804         struct se_device *dev,
 805         char *b,
 806         int *bl)
 807 {
 808         *bl += sprintf(b + *bl, "Status: ");
 809         if (dev->export_count)
 810                 *bl += sprintf(b + *bl, "ACTIVATED");
 811         else
 812                 *bl += sprintf(b + *bl, "DEACTIVATED");
 813
 814         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 815         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 816                 dev->dev_attrib.block_size,
 817                 dev->dev_attrib.hw_max_sectors);
 818         *bl += sprintf(b + *bl, "        ");
 819 }
 820
 821 void transport_dump_vpd_proto_id(
 822         struct t10_vpd *vpd,
 823         unsigned char *p_buf,
 824         int p_buf_len)
 825 {
 826         unsigned char buf[VPD_TMP_BUF_SIZE];
 827         int len;
 828
 829         memset(buf, 0, VPD_TMP_BUF_SIZE);
 830         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 831
 832         switch (vpd->protocol_identifier) {
 833         case 0x00:
 834                 sprintf(buf+len, "Fibre Channel\n");
 835                 break;
 836         case 0x10:
 837                 sprintf(buf+len, "Parallel SCSI\n");
 838                 break;
 839         case 0x20:
 840                 sprintf(buf+len, "SSA\n");
 841                 break;
 842         case 0x30:
 843                 sprintf(buf+len, "IEEE 1394\n");
 844                 break;
 845         case 0x40:
 846                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 847                                 " Protocol\n");
 848                 break;
 849         case 0x50:
 850                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 851                 break;
 852         case 0x60:
 853                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 854                 break;
 855         case 0x70:
 856                 sprintf(buf+len, "Automation/Drive Interface Transport"
 857                                 " Protocol\n");
 858                 break;
 859         case 0x80:
 860                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 861                 break;
 862         default:
 863                 sprintf(buf+len, "Unknown 0x%02x\n",
 864                                 vpd->protocol_identifier);
 865                 break;
 866         }
 867
 868         if (p_buf)
 869                 strncpy(p_buf, buf, p_buf_len);
 870         else
 871                 pr_debug("%s", buf);
 872 }
 873
 874 void
 875 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 876 {
 877         /*
 878          * Check if the Protocol Identifier Valid (PIV) bit is set..
 879          *
 880          * from spc3r23.pdf section 7.5.1
 881          */
 882          if (page_83[1] & 0x80) {
 883                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 884                 vpd->protocol_identifier_set = 1;
 885                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 886         }
 887 }
 888 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 889
 890 int transport_dump_vpd_assoc(
 891         struct t10_vpd *vpd,
 892         unsigned char *p_buf,
 893         int p_buf_len)
 894 {
 895         unsigned char buf[VPD_TMP_BUF_SIZE];
 896         int ret = 0;
 897         int len;
 898
 899         memset(buf, 0, VPD_TMP_BUF_SIZE);
 900         len = sprintf(buf, "T10 VPD Identifier Association: ");
 901
 902         switch (vpd->association) {
 903         case 0x00:
 904                 sprintf(buf+len, "addressed logical unit\n");
 905                 break;
 906         case 0x10:
 907                 sprintf(buf+len, "target port\n");
 908                 break;
 909         case 0x20:
 910                 sprintf(buf+len, "SCSI target device\n");
 911                 break;
 912         default:
 913                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 914                 ret = -EINVAL;
 915                 break;
 916         }
 917
 918         if (p_buf)
 919                 strncpy(p_buf, buf, p_buf_len);
 920         else
 921                 pr_debug("%s", buf);
 922
 923         return ret;
 924 }
 925
 926 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 927 {
 928         /*
 929          * The VPD identification association..
 930          *
 931          * from spc3r23.pdf Section 7.6.3.1 Table 297
 932          */
 933         vpd->association = (page_83[1] & 0x30);
 934         return transport_dump_vpd_assoc(vpd, NULL, 0);
 935 }
 936 EXPORT_SYMBOL(transport_set_vpd_assoc);
 937
 938 int transport_dump_vpd_ident_type(
 939         struct t10_vpd *vpd,
 940         unsigned char *p_buf,
 941         int p_buf_len)
 942 {
 943         unsigned char buf[VPD_TMP_BUF_SIZE];
 944         int ret = 0;
 945         int len;
 946
 947         memset(buf, 0, VPD_TMP_BUF_SIZE);
 948         len = sprintf(buf, "T10 VPD Identifier Type: ");
 949
 950         switch (vpd->device_identifier_type) {
 951         case 0x00:
 952                 sprintf(buf+len, "Vendor specific\n");
 953                 break;
 954         case 0x01:
 955                 sprintf(buf+len, "T10 Vendor ID based\n");
 956                 break;
 957         case 0x02:
 958                 sprintf(buf+len, "EUI-64 based\n");
 959                 break;
 960         case 0x03:
 961                 sprintf(buf+len, "NAA\n");
 962                 break;
 963         case 0x04:
 964                 sprintf(buf+len, "Relative target port identifier\n");
 965                 break;
 966         case 0x08:
 967                 sprintf(buf+len, "SCSI name string\n");
 968                 break;
 969         default:
 970                 sprintf(buf+len, "Unsupported: 0x%02x\n",
 971                                 vpd->device_identifier_type);
 972                 ret = -EINVAL;
 973                 break;
 974         }
 975
 976         if (p_buf) {
 977                 if (p_buf_len < strlen(buf)+1)
 978                         return -EINVAL;
 979                 strncpy(p_buf, buf, p_buf_len);
 980         } else {
 981                 pr_debug("%s", buf);
 982         }
 983
 984         return ret;
 985 }
 986
 987 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
 988 {
 989         /*
 990          * The VPD identifier type..
 991          *
 992          * from spc3r23.pdf Section 7.6.3.1 Table 298
 993          */
 994         vpd->device_identifier_type = (page_83[1] & 0x0f);
 995         return transport_dump_vpd_ident_type(vpd, NULL, 0);
 996 }
 997 EXPORT_SYMBOL(transport_set_vpd_ident_type);
 998
 999 int transport_dump_vpd_ident(
1000         struct t10_vpd *vpd,
1001         unsigned char *p_buf,
1002         int p_buf_len)
1003 {
1004         unsigned char buf[VPD_TMP_BUF_SIZE];
1005         int ret = 0;
1006
1007         memset(buf, 0, VPD_TMP_BUF_SIZE);
1008
1009         switch (vpd->device_identifier_code_set) {
1010         case 0x01: /* Binary */
1011                 snprintf(buf, sizeof(buf),
1012                         "T10 VPD Binary Device Identifier: %s\n",
1013                         &vpd->device_identifier[0]);
1014                 break;
1015         case 0x02: /* ASCII */
1016                 snprintf(buf, sizeof(buf),
1017                         "T10 VPD ASCII Device Identifier: %s\n",
1018                         &vpd->device_identifier[0]);
1019                 break;
1020         case 0x03: /* UTF-8 */
1021                 snprintf(buf, sizeof(buf),
1022                         "T10 VPD UTF-8 Device Identifier: %s\n",
1023                         &vpd->device_identifier[0]);
1024                 break;
1025         default:
1026                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1027                         " 0x%02x", vpd->device_identifier_code_set);
1028                 ret = -EINVAL;
1029                 break;
1030         }
1031
1032         if (p_buf)
1033                 strncpy(p_buf, buf, p_buf_len);
1034         else
1035                 pr_debug("%s", buf);
1036
1037         return ret;
1038 }
1039
1040 int
1041 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1042 {
1043         static const char hex_str[] = "0123456789abcdef";
1044         int j = 0, i = 4; /* offset to start of the identifier */
1045
1046         /*
1047          * The VPD Code Set (encoding)
1048          *
1049          * from spc3r23.pdf Section 7.6.3.1 Table 296
1050          */
1051         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1052         switch (vpd->device_identifier_code_set) {
1053         case 0x01: /* Binary */
1054                 vpd->device_identifier[j++] =
1055                                 hex_str[vpd->device_identifier_type];
1056                 while (i < (4 + page_83[3])) {
1057                         vpd->device_identifier[j++] =
1058                                 hex_str[(page_83[i] & 0xf0) >> 4];
1059                         vpd->device_identifier[j++] =
1060                                 hex_str[page_83[i] & 0x0f];
1061                         i++;
1062                 }
1063                 break;
1064         case 0x02: /* ASCII */
1065         case 0x03: /* UTF-8 */
1066                 while (i < (4 + page_83[3]))
1067                         vpd->device_identifier[j++] = page_83[i++];
1068                 break;
1069         default:
1070                 break;
1071         }
1072
1073         return transport_dump_vpd_ident(vpd, NULL, 0);
1074 }
1075 EXPORT_SYMBOL(transport_set_vpd_ident);
1076
1077 static sense_reason_t
1078 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1079                                unsigned int size)
1080 {
1081         u32 mtl;
1082
1083         if (!cmd->se_tfo->max_data_sg_nents)
1084                 return TCM_NO_SENSE;
1085         /*
1086          * Check if fabric enforced maximum SGL entries per I/O descriptor
1087          * exceeds se_cmd->data_length.  If true, set SCF_UNDERFLOW_BIT +
1088          * residual_count and reduce original cmd->data_length to maximum
1089          * length based on single PAGE_SIZE entry scatter-lists.
1090          */
1091         mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1092         if (cmd->data_length > mtl) {
1093                 /*
1094                  * If an existing CDB overflow is present, calculate new residual
1095                  * based on CDB size minus fabric maximum transfer length.
1096                  *
1097                  * If an existing CDB underflow is present, calculate new residual
1098                  * based on original cmd->data_length minus fabric maximum transfer
1099                  * length.
1100                  *
1101                  * Otherwise, set the underflow residual based on cmd->data_length
1102                  * minus fabric maximum transfer length.
1103                  */
1104                 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1105                         cmd->residual_count = (size - mtl);
1106                 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1107                         u32 orig_dl = size + cmd->residual_count;
1108                         cmd->residual_count = (orig_dl - mtl);
1109                 } else {
1110                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1111                         cmd->residual_count = (cmd->data_length - mtl);
1112                 }
1113                 cmd->data_length = mtl;
1114                 /*
1115                  * Reset sbc_check_prot() calculated protection payload
1116                  * length based upon the new smaller MTL.
1117                  */
1118                 if (cmd->prot_length) {
1119                         u32 sectors = (mtl / dev->dev_attrib.block_size);
1120                         cmd->prot_length = dev->prot_length * sectors;
1121                 }
1122         }
1123         return TCM_NO_SENSE;
1124 }
1125
1126 sense_reason_t
1127 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1128 {
1129         struct se_device *dev = cmd->se_dev;
1130
1131         if (cmd->unknown_data_length) {
1132                 cmd->data_length = size;
1133         } else if (size != cmd->data_length) {
1134                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1135                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1136                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1137                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1138
1139                 if (cmd->data_direction == DMA_TO_DEVICE &&
1140                     cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1141                         pr_err("Rejecting underflow/overflow WRITE data\n");
1142                         return TCM_INVALID_CDB_FIELD;
1143                 }
1144                 /*
1145                  * Reject READ_* or WRITE_* with overflow/underflow for
1146                  * type SCF_SCSI_DATA_CDB.
1147                  */
1148                 if (dev->dev_attrib.block_size != 512)  {
1149                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1150                                 " CDB on non 512-byte sector setup subsystem"
1151                                 " plugin: %s\n", dev->transport->name);
1152                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1153                         return TCM_INVALID_CDB_FIELD;
1154                 }
1155                 /*
1156                  * For the overflow case keep the existing fabric provided
1157                  * ->data_length.  Otherwise for the underflow case, reset
1158                  * ->data_length to the smaller SCSI expected data transfer
1159                  * length.
1160                  */
1161                 if (size > cmd->data_length) {
1162                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1163                         cmd->residual_count = (size - cmd->data_length);
1164                 } else {
1165                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1166                         cmd->residual_count = (cmd->data_length - size);
1167                         cmd->data_length = size;
1168                 }
1169         }
1170
1171         return target_check_max_data_sg_nents(cmd, dev, size);
1172
1173 }
1174
1175 /*
1176  * Used by fabric modules containing a local struct se_cmd within their
1177  * fabric dependent per I/O descriptor.
1178  *
1179  * Preserves the value of @cmd->tag.
1180  */
1181 void transport_init_se_cmd(
1182         struct se_cmd *cmd,
1183         const struct target_core_fabric_ops *tfo,
1184         struct se_session *se_sess,
1185         u32 data_length,
1186         int data_direction,
1187         int task_attr,
1188         unsigned char *sense_buffer)
1189 {
1190         INIT_LIST_HEAD(&cmd->se_delayed_node);
1191         INIT_LIST_HEAD(&cmd->se_qf_node);
1192         INIT_LIST_HEAD(&cmd->se_cmd_list);
1193         INIT_LIST_HEAD(&cmd->state_list);
1194         init_completion(&cmd->t_transport_stop_comp);
1195         init_completion(&cmd->cmd_wait_comp);
1196         init_completion(&cmd->task_stop_comp);
1197         spin_lock_init(&cmd->t_state_lock);
1198         kref_init(&cmd->cmd_kref);
1199         cmd->transport_state = CMD_T_DEV_ACTIVE;
1200
1201         cmd->se_tfo = tfo;
1202         cmd->se_sess = se_sess;
1203         cmd->data_length = data_length;
1204         cmd->data_direction = data_direction;
1205         cmd->sam_task_attr = task_attr;
1206         cmd->sense_buffer = sense_buffer;
1207
1208         cmd->state_active = false;
1209 }
1210 EXPORT_SYMBOL(transport_init_se_cmd);
1211
1212 static sense_reason_t
1213 transport_check_alloc_task_attr(struct se_cmd *cmd)
1214 {
1215         struct se_device *dev = cmd->se_dev;
1216
1217         /*
1218          * Check if SAM Task Attribute emulation is enabled for this
1219          * struct se_device storage object
1220          */
1221         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1222                 return 0;
1223
1224         if (cmd->sam_task_attr == TCM_ACA_TAG) {
1225                 pr_debug("SAM Task Attribute ACA"
1226                         " emulation is not supported\n");
1227                 return TCM_INVALID_CDB_FIELD;
1228         }
1229
1230         return 0;
1231 }
1232
1233 sense_reason_t
1234 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1235 {
1236         struct se_device *dev = cmd->se_dev;
1237         sense_reason_t ret;
1238
1239         /*
1240          * Ensure that the received CDB is less than the max (252 + 8) bytes
1241          * for VARIABLE_LENGTH_CMD
1242          */
1243         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1244                 pr_err("Received SCSI CDB with command_size: %d that"
1245                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1246                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1247                 return TCM_INVALID_CDB_FIELD;
1248         }
1249         /*
1250          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1251          * allocate the additional extended CDB buffer now..  Otherwise
1252          * setup the pointer from __t_task_cdb to t_task_cdb.
1253          */
1254         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1255                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1256                                                 GFP_KERNEL);
1257                 if (!cmd->t_task_cdb) {
1258                         pr_err("Unable to allocate cmd->t_task_cdb"
1259                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1260                                 scsi_command_size(cdb),
1261                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1262                         return TCM_OUT_OF_RESOURCES;
1263                 }
1264         } else
1265                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1266         /*
1267          * Copy the original CDB into cmd->
1268          */
1269         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1270
1271         trace_target_sequencer_start(cmd);
1272
1273         ret = dev->transport->parse_cdb(cmd);
1274         if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1275                 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1276                                     cmd->se_tfo->get_fabric_name(),
1277                                     cmd->se_sess->se_node_acl->initiatorname,
1278                                     cmd->t_task_cdb[0]);
1279         if (ret)
1280                 return ret;
1281
1282         ret = transport_check_alloc_task_attr(cmd);
1283         if (ret)
1284                 return ret;
1285
1286         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1287         atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1288         return 0;
1289 }
1290 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1291
1292 /*
1293  * Used by fabric module frontends to queue tasks directly.
1294  * Many only be used from process context only
1295  */
1296 int transport_handle_cdb_direct(
1297         struct se_cmd *cmd)
1298 {
1299         sense_reason_t ret;
1300
1301         if (!cmd->se_lun) {
1302                 dump_stack();
1303                 pr_err("cmd->se_lun is NULL\n");
1304                 return -EINVAL;
1305         }
1306         if (in_interrupt()) {
1307                 dump_stack();
1308                 pr_err("transport_generic_handle_cdb cannot be called"
1309                                 " from interrupt context\n");
1310                 return -EINVAL;
1311         }
1312         /*
1313          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1314          * outstanding descriptors are handled correctly during shutdown via
1315          * transport_wait_for_tasks()
1316          *
1317          * Also, we don't take cmd->t_state_lock here as we only expect
1318          * this to be called for initial descriptor submission.
1319          */
1320         cmd->t_state = TRANSPORT_NEW_CMD;
1321         cmd->transport_state |= CMD_T_ACTIVE;
1322
1323         /*
1324          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1325          * so follow TRANSPORT_NEW_CMD processing thread context usage
1326          * and call transport_generic_request_failure() if necessary..
1327          */
1328         ret = transport_generic_new_cmd(cmd);
1329         if (ret)
1330                 transport_generic_request_failure(cmd, ret);
1331         return 0;
1332 }
1333 EXPORT_SYMBOL(transport_handle_cdb_direct);
1334
1335 sense_reason_t
1336 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1337                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1338 {
1339         if (!sgl || !sgl_count)
1340                 return 0;
1341
1342         /*
1343          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1344          * scatterlists already have been set to follow what the fabric
1345          * passes for the original expected data transfer length.
1346          */
1347         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1348                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1349                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1350                 return TCM_INVALID_CDB_FIELD;
1351         }
1352
1353         cmd->t_data_sg = sgl;
1354         cmd->t_data_nents = sgl_count;
1355         cmd->t_bidi_data_sg = sgl_bidi;
1356         cmd->t_bidi_data_nents = sgl_bidi_count;
1357
1358         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1359         return 0;
1360 }
1361
1362 /*
1363  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1364  *                       se_cmd + use pre-allocated SGL memory.
1365  *
1366  * @se_cmd: command descriptor to submit
1367  * @se_sess: associated se_sess for endpoint
1368  * @cdb: pointer to SCSI CDB
1369  * @sense: pointer to SCSI sense buffer
1370  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1371  * @data_length: fabric expected data transfer length
1372  * @task_addr: SAM task attribute
1373  * @data_dir: DMA data direction
1374  * @flags: flags for command submission from target_sc_flags_tables
1375  * @sgl: struct scatterlist memory for unidirectional mapping
1376  * @sgl_count: scatterlist count for unidirectional mapping
1377  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1378  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1379  * @sgl_prot: struct scatterlist memory protection information
1380  * @sgl_prot_count: scatterlist count for protection information
1381  *
1382  * Task tags are supported if the caller has set @se_cmd->tag.
1383  *
1384  * Returns non zero to signal active I/O shutdown failure.  All other
1385  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1386  * but still return zero here.
1387  *
1388  * This may only be called from process context, and also currently
1389  * assumes internal allocation of fabric payload buffer by target-core.
1390  */
1391 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1392                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1393                 u32 data_length, int task_attr, int data_dir, int flags,
1394                 struct scatterlist *sgl, u32 sgl_count,
1395                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1396                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1397 {
1398         struct se_portal_group *se_tpg;
1399         sense_reason_t rc;
1400         int ret;
1401
1402         se_tpg = se_sess->se_tpg;
1403         BUG_ON(!se_tpg);
1404         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1405         BUG_ON(in_interrupt());
1406         /*
1407          * Initialize se_cmd for target operation.  From this point
1408          * exceptions are handled by sending exception status via
1409          * target_core_fabric_ops->queue_status() callback
1410          */
1411         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1412                                 data_length, data_dir, task_attr, sense);
1413         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1414                 se_cmd->unknown_data_length = 1;
1415         /*
1416          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1417          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1418          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1419          * kref_put() to happen during fabric packet acknowledgement.
1420          */
1421         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1422         if (ret)
1423                 return ret;
1424         /*
1425          * Signal bidirectional data payloads to target-core
1426          */
1427         if (flags & TARGET_SCF_BIDI_OP)
1428                 se_cmd->se_cmd_flags |= SCF_BIDI;
1429         /*
1430          * Locate se_lun pointer and attach it to struct se_cmd
1431          */
1432         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1433         if (rc) {
1434                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1435                 target_put_sess_cmd(se_cmd);
1436                 return 0;
1437         }
1438
1439         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1440         if (rc != 0) {
1441                 transport_generic_request_failure(se_cmd, rc);
1442                 return 0;
1443         }
1444
1445         /*
1446          * Save pointers for SGLs containing protection information,
1447          * if present.
1448          */
1449         if (sgl_prot_count) {
1450                 se_cmd->t_prot_sg = sgl_prot;
1451                 se_cmd->t_prot_nents = sgl_prot_count;
1452                 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1453         }
1454
1455         /*
1456          * When a non zero sgl_count has been passed perform SGL passthrough
1457          * mapping for pre-allocated fabric memory instead of having target
1458          * core perform an internal SGL allocation..
1459          */
1460         if (sgl_count != 0) {
1461                 BUG_ON(!sgl);
1462
1463                 /*
1464                  * A work-around for tcm_loop as some userspace code via
1465                  * scsi-generic do not memset their associated read buffers,
1466                  * so go ahead and do that here for type non-data CDBs.  Also
1467                  * note that this is currently guaranteed to be a single SGL
1468                  * for this case by target core in target_setup_cmd_from_cdb()
1469                  * -> transport_generic_cmd_sequencer().
1470                  */
1471                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1472                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1473                         unsigned char *buf = NULL;
1474
1475                         if (sgl)
1476                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1477
1478                         if (buf) {
1479                                 memset(buf, 0, sgl->length);
1480                                 kunmap(sg_page(sgl));
1481                         }
1482                 }
1483
1484                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1485                                 sgl_bidi, sgl_bidi_count);
1486                 if (rc != 0) {
1487                         transport_generic_request_failure(se_cmd, rc);
1488                         return 0;
1489                 }
1490         }
1491
1492         /*
1493          * Check if we need to delay processing because of ALUA
1494          * Active/NonOptimized primary access state..
1495          */
1496         core_alua_check_nonop_delay(se_cmd);
1497
1498         transport_handle_cdb_direct(se_cmd);
1499         return 0;
1500 }
1501 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1502
1503 /*
1504  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1505  *
1506  * @se_cmd: command descriptor to submit
1507  * @se_sess: associated se_sess for endpoint
1508  * @cdb: pointer to SCSI CDB
1509  * @sense: pointer to SCSI sense buffer
1510  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1511  * @data_length: fabric expected data transfer length
1512  * @task_addr: SAM task attribute
1513  * @data_dir: DMA data direction
1514  * @flags: flags for command submission from target_sc_flags_tables
1515  *
1516  * Task tags are supported if the caller has set @se_cmd->tag.
1517  *
1518  * Returns non zero to signal active I/O shutdown failure.  All other
1519  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1520  * but still return zero here.
1521  *
1522  * This may only be called from process context, and also currently
1523  * assumes internal allocation of fabric payload buffer by target-core.
1524  *
1525  * It also assumes interal target core SGL memory allocation.
1526  */
1527 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1528                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1529                 u32 data_length, int task_attr, int data_dir, int flags)
1530 {
1531         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1532                         unpacked_lun, data_length, task_attr, data_dir,
1533                         flags, NULL, 0, NULL, 0, NULL, 0);
1534 }
1535 EXPORT_SYMBOL(target_submit_cmd);
1536
1537 static void target_complete_tmr_failure(struct work_struct *work)
1538 {
1539         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1540
1541         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1542         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1543
1544         transport_cmd_check_stop_to_fabric(se_cmd);
1545 }
1546
1547 /**
1548  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1549  *                     for TMR CDBs
1550  *
1551  * @se_cmd: command descriptor to submit
1552  * @se_sess: associated se_sess for endpoint
1553  * @sense: pointer to SCSI sense buffer
1554  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1555  * @fabric_context: fabric context for TMR req
1556  * @tm_type: Type of TM request
1557  * @gfp: gfp type for caller
1558  * @tag: referenced task tag for TMR_ABORT_TASK
1559  * @flags: submit cmd flags
1560  *
1561  * Callable from all contexts.
1562  **/
1563
1564 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1565                 unsigned char *sense, u64 unpacked_lun,
1566                 void *fabric_tmr_ptr, unsigned char tm_type,
1567                 gfp_t gfp, unsigned int tag, int flags)
1568 {
1569         struct se_portal_group *se_tpg;
1570         int ret;
1571
1572         se_tpg = se_sess->se_tpg;
1573         BUG_ON(!se_tpg);
1574
1575         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1576                               0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1577         /*
1578          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1579          * allocation failure.
1580          */
1581         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1582         if (ret < 0)
1583                 return -ENOMEM;
1584
1585         if (tm_type == TMR_ABORT_TASK)
1586                 se_cmd->se_tmr_req->ref_task_tag = tag;
1587
1588         /* See target_submit_cmd for commentary */
1589         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1590         if (ret) {
1591                 core_tmr_release_req(se_cmd->se_tmr_req);
1592                 return ret;
1593         }
1594
1595         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1596         if (ret) {
1597                 /*
1598                  * For callback during failure handling, push this work off
1599                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1600                  */
1601                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1602                 schedule_work(&se_cmd->work);
1603                 return 0;
1604         }
1605         transport_generic_handle_tmr(se_cmd);
1606         return 0;
1607 }
1608 EXPORT_SYMBOL(target_submit_tmr);
1609
1610 /*
1611  * If the cmd is active, request it to be stopped and sleep until it
1612  * has completed.
1613  */
1614 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1615         __releases(&cmd->t_state_lock)
1616         __acquires(&cmd->t_state_lock)
1617 {
1618         bool was_active = false;
1619
1620         if (cmd->transport_state & CMD_T_BUSY) {
1621                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1622                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1623
1624                 pr_debug("cmd %p waiting to complete\n", cmd);
1625                 wait_for_completion(&cmd->task_stop_comp);
1626                 pr_debug("cmd %p stopped successfully\n", cmd);
1627
1628                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1629                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1630                 cmd->transport_state &= ~CMD_T_BUSY;
1631                 was_active = true;
1632         }
1633
1634         return was_active;
1635 }
1636
1637 /*
1638  * Handle SAM-esque emulation for generic transport request failures.
1639  */
1640 void transport_generic_request_failure(struct se_cmd *cmd,
1641                 sense_reason_t sense_reason)
1642 {
1643         int ret = 0, post_ret = 0;
1644
1645         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08llx"
1646                 " CDB: 0x%02x\n", cmd, cmd->tag, cmd->t_task_cdb[0]);
1647         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1648                 cmd->se_tfo->get_cmd_state(cmd),
1649                 cmd->t_state, sense_reason);
1650         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1651                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1652                 (cmd->transport_state & CMD_T_STOP) != 0,
1653                 (cmd->transport_state & CMD_T_SENT) != 0);
1654
1655         /*
1656          * For SAM Task Attribute emulation for failed struct se_cmd
1657          */
1658         transport_complete_task_attr(cmd);
1659         /*
1660          * Handle special case for COMPARE_AND_WRITE failure, where the
1661          * callback is expected to drop the per device ->caw_sem.
1662          */
1663         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1664              cmd->transport_complete_callback)
1665                 cmd->transport_complete_callback(cmd, false, &post_ret);
1666
1667         switch (sense_reason) {
1668         case TCM_NON_EXISTENT_LUN:
1669         case TCM_UNSUPPORTED_SCSI_OPCODE:
1670         case TCM_INVALID_CDB_FIELD:
1671         case TCM_INVALID_PARAMETER_LIST:
1672         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1673         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1674         case TCM_UNKNOWN_MODE_PAGE:
1675         case TCM_WRITE_PROTECTED:
1676         case TCM_ADDRESS_OUT_OF_RANGE:
1677         case TCM_CHECK_CONDITION_ABORT_CMD:
1678         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1679         case TCM_CHECK_CONDITION_NOT_READY:
1680         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1681         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1682         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1683         case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
1684                 break;
1685         case TCM_OUT_OF_RESOURCES:
1686                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1687                 break;
1688         case TCM_RESERVATION_CONFLICT:
1689                 /*
1690                  * No SENSE Data payload for this case, set SCSI Status
1691                  * and queue the response to $FABRIC_MOD.
1692                  *
1693                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1694                  */
1695                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1696                 /*
1697                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1698                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1699                  * CONFLICT STATUS.
1700                  *
1701                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1702                  */
1703                 if (cmd->se_sess &&
1704                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1705                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1706                                                cmd->orig_fe_lun, 0x2C,
1707                                         ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1708                 }
1709                 trace_target_cmd_complete(cmd);
1710                 ret = cmd->se_tfo->queue_status(cmd);
1711                 if (ret == -EAGAIN || ret == -ENOMEM)
1712                         goto queue_full;
1713                 goto check_stop;
1714         default:
1715                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1716                         cmd->t_task_cdb[0], sense_reason);
1717                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1718                 break;
1719         }
1720
1721         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1722         if (ret == -EAGAIN || ret == -ENOMEM)
1723                 goto queue_full;
1724
1725 check_stop:
1726         transport_lun_remove_cmd(cmd);
1727         transport_cmd_check_stop_to_fabric(cmd);
1728         return;
1729
1730 queue_full:
1731         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1732         transport_handle_queue_full(cmd, cmd->se_dev);
1733 }
1734 EXPORT_SYMBOL(transport_generic_request_failure);
1735
1736 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
1737 {
1738         sense_reason_t ret;
1739
1740         if (!cmd->execute_cmd) {
1741                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1742                 goto err;
1743         }
1744         if (do_checks) {
1745                 /*
1746                  * Check for an existing UNIT ATTENTION condition after
1747                  * target_handle_task_attr() has done SAM task attr
1748                  * checking, and possibly have already defered execution
1749                  * out to target_restart_delayed_cmds() context.
1750                  */
1751                 ret = target_scsi3_ua_check(cmd);
1752                 if (ret)
1753                         goto err;
1754
1755                 ret = target_alua_state_check(cmd);
1756                 if (ret)
1757                         goto err;
1758
1759                 ret = target_check_reservation(cmd);
1760                 if (ret) {
1761                         cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1762                         goto err;
1763                 }
1764         }
1765
1766         ret = cmd->execute_cmd(cmd);
1767         if (!ret)
1768                 return;
1769 err:
1770         spin_lock_irq(&cmd->t_state_lock);
1771         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1772         spin_unlock_irq(&cmd->t_state_lock);
1773
1774         transport_generic_request_failure(cmd, ret);
1775 }
1776
1777 static int target_write_prot_action(struct se_cmd *cmd)
1778 {
1779         u32 sectors;
1780         /*
1781          * Perform WRITE_INSERT of PI using software emulation when backend
1782          * device has PI enabled, if the transport has not already generated
1783          * PI using hardware WRITE_INSERT offload.
1784          */
1785         switch (cmd->prot_op) {
1786         case TARGET_PROT_DOUT_INSERT:
1787                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1788                         sbc_dif_generate(cmd);
1789                 break;
1790         case TARGET_PROT_DOUT_STRIP:
1791                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1792                         break;
1793
1794                 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1795                 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1796                                              sectors, 0, cmd->t_prot_sg, 0);
1797                 if (unlikely(cmd->pi_err)) {
1798                         spin_lock_irq(&cmd->t_state_lock);
1799                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1800                         spin_unlock_irq(&cmd->t_state_lock);
1801                         transport_generic_request_failure(cmd, cmd->pi_err);
1802                         return -1;
1803                 }
1804                 break;
1805         default:
1806                 break;
1807         }
1808
1809         return 0;
1810 }
1811
1812 static bool target_handle_task_attr(struct se_cmd *cmd)
1813 {
1814         struct se_device *dev = cmd->se_dev;
1815
1816         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1817                 return false;
1818
1819         cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
1820
1821         /*
1822          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1823          * to allow the passed struct se_cmd list of tasks to the front of the list.
1824          */
1825         switch (cmd->sam_task_attr) {
1826         case TCM_HEAD_TAG:
1827                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1828                          cmd->t_task_cdb[0]);
1829                 return false;
1830         case TCM_ORDERED_TAG:
1831                 atomic_inc_mb(&dev->dev_ordered_sync);
1832
1833                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1834                          cmd->t_task_cdb[0]);
1835
1836                 /*
1837                  * Execute an ORDERED command if no other older commands
1838                  * exist that need to be completed first.
1839                  */
1840                 if (!atomic_read(&dev->simple_cmds))
1841                         return false;
1842                 break;
1843         default:
1844                 /*
1845                  * For SIMPLE and UNTAGGED Task Attribute commands
1846                  */
1847                 atomic_inc_mb(&dev->simple_cmds);
1848                 break;
1849         }
1850
1851         if (atomic_read(&dev->dev_ordered_sync) == 0)
1852                 return false;
1853
1854         spin_lock(&dev->delayed_cmd_lock);
1855         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1856         spin_unlock(&dev->delayed_cmd_lock);
1857
1858         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
1859                 cmd->t_task_cdb[0], cmd->sam_task_attr);
1860         return true;
1861 }
1862
1863 static int __transport_check_aborted_status(struct se_cmd *, int);
1864
1865 void target_execute_cmd(struct se_cmd *cmd)
1866 {
1867         /*
1868          * Determine if frontend context caller is requesting the stopping of
1869          * this command for frontend exceptions.
1870          *
1871          * If the received CDB has aleady been aborted stop processing it here.
1872          */
1873         spin_lock_irq(&cmd->t_state_lock);
1874         if (__transport_check_aborted_status(cmd, 1)) {
1875                 spin_unlock_irq(&cmd->t_state_lock);
1876                 return;
1877         }
1878         if (cmd->transport_state & CMD_T_STOP) {
1879                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1880                         __func__, __LINE__, cmd->tag);
1881
1882                 spin_unlock_irq(&cmd->t_state_lock);
1883                 complete_all(&cmd->t_transport_stop_comp);
1884                 return;
1885         }
1886
1887         cmd->t_state = TRANSPORT_PROCESSING;
1888         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1889         spin_unlock_irq(&cmd->t_state_lock);
1890
1891         if (target_write_prot_action(cmd))
1892                 return;
1893
1894         if (target_handle_task_attr(cmd)) {
1895                 spin_lock_irq(&cmd->t_state_lock);
1896                 cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1897                 spin_unlock_irq(&cmd->t_state_lock);
1898                 return;
1899         }
1900
1901         __target_execute_cmd(cmd, true);
1902 }
1903 EXPORT_SYMBOL(target_execute_cmd);
1904
1905 /*
1906  * Process all commands up to the last received ORDERED task attribute which
1907  * requires another blocking boundary
1908  */
1909 static void target_restart_delayed_cmds(struct se_device *dev)
1910 {
1911         for (;;) {
1912                 struct se_cmd *cmd;
1913
1914                 spin_lock(&dev->delayed_cmd_lock);
1915                 if (list_empty(&dev->delayed_cmd_list)) {
1916                         spin_unlock(&dev->delayed_cmd_lock);
1917                         break;
1918                 }
1919
1920                 cmd = list_entry(dev->delayed_cmd_list.next,
1921                                  struct se_cmd, se_delayed_node);
1922                 list_del(&cmd->se_delayed_node);
1923                 spin_unlock(&dev->delayed_cmd_lock);
1924
1925                 __target_execute_cmd(cmd, true);
1926
1927                 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1928                         break;
1929         }
1930 }
1931
1932 /*
1933  * Called from I/O completion to determine which dormant/delayed
1934  * and ordered cmds need to have their tasks added to the execution queue.
1935  */
1936 static void transport_complete_task_attr(struct se_cmd *cmd)
1937 {
1938         struct se_device *dev = cmd->se_dev;
1939
1940         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1941                 return;
1942
1943         if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
1944                 goto restart;
1945
1946         if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1947                 atomic_dec_mb(&dev->simple_cmds);
1948                 dev->dev_cur_ordered_id++;
1949                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for SIMPLE\n",
1950                          dev->dev_cur_ordered_id);
1951         } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1952                 dev->dev_cur_ordered_id++;
1953                 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
1954                          dev->dev_cur_ordered_id);
1955         } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1956                 atomic_dec_mb(&dev->dev_ordered_sync);
1957
1958                 dev->dev_cur_ordered_id++;
1959                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
1960                          dev->dev_cur_ordered_id);
1961         }
1962 restart:
1963         target_restart_delayed_cmds(dev);
1964 }
1965
1966 static void transport_complete_qf(struct se_cmd *cmd)
1967 {
1968         int ret = 0;
1969
1970         transport_complete_task_attr(cmd);
1971
1972         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1973                 trace_target_cmd_complete(cmd);
1974                 ret = cmd->se_tfo->queue_status(cmd);
1975                 goto out;
1976         }
1977
1978         switch (cmd->data_direction) {
1979         case DMA_FROM_DEVICE:
1980                 trace_target_cmd_complete(cmd);
1981                 ret = cmd->se_tfo->queue_data_in(cmd);
1982                 break;
1983         case DMA_TO_DEVICE:
1984                 if (cmd->se_cmd_flags & SCF_BIDI) {
1985                         ret = cmd->se_tfo->queue_data_in(cmd);
1986                         break;
1987                 }
1988                 /* Fall through for DMA_TO_DEVICE */
1989         case DMA_NONE:
1990                 trace_target_cmd_complete(cmd);
1991                 ret = cmd->se_tfo->queue_status(cmd);
1992                 break;
1993         default:
1994                 break;
1995         }
1996
1997 out:
1998         if (ret < 0) {
1999                 transport_handle_queue_full(cmd, cmd->se_dev);
2000                 return;
2001         }
2002         transport_lun_remove_cmd(cmd);
2003         transport_cmd_check_stop_to_fabric(cmd);
2004 }
2005
2006 static void transport_handle_queue_full(
2007         struct se_cmd *cmd,
2008         struct se_device *dev)
2009 {
2010         spin_lock_irq(&dev->qf_cmd_lock);
2011         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2012         atomic_inc_mb(&dev->dev_qf_count);
2013         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2014
2015         schedule_work(&cmd->se_dev->qf_work_queue);
2016 }
2017
2018 static bool target_read_prot_action(struct se_cmd *cmd)
2019 {
2020         switch (cmd->prot_op) {
2021         case TARGET_PROT_DIN_STRIP:
2022                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2023                         u32 sectors = cmd->data_length >>
2024                                   ilog2(cmd->se_dev->dev_attrib.block_size);
2025
2026                         cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2027                                                      sectors, 0, cmd->t_prot_sg,
2028                                                      0);
2029                         if (cmd->pi_err)
2030                                 return true;
2031                 }
2032                 break;
2033         case TARGET_PROT_DIN_INSERT:
2034                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2035                         break;
2036
2037                 sbc_dif_generate(cmd);
2038                 break;
2039         default:
2040                 break;
2041         }
2042
2043         return false;
2044 }
2045
2046 static void target_complete_ok_work(struct work_struct *work)
2047 {
2048         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2049         int ret;
2050
2051         /*
2052          * Check if we need to move delayed/dormant tasks from cmds on the
2053          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2054          * Attribute.
2055          */
2056         transport_complete_task_attr(cmd);
2057
2058         /*
2059          * Check to schedule QUEUE_FULL work, or execute an existing
2060          * cmd->transport_qf_callback()
2061          */
2062         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2063                 schedule_work(&cmd->se_dev->qf_work_queue);
2064
2065         /*
2066          * Check if we need to send a sense buffer from
2067          * the struct se_cmd in question.
2068          */
2069         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2070                 WARN_ON(!cmd->scsi_status);
2071                 ret = transport_send_check_condition_and_sense(
2072                                         cmd, 0, 1);
2073                 if (ret == -EAGAIN || ret == -ENOMEM)
2074                         goto queue_full;
2075
2076                 transport_lun_remove_cmd(cmd);
2077                 transport_cmd_check_stop_to_fabric(cmd);
2078                 return;
2079         }
2080         /*
2081          * Check for a callback, used by amongst other things
2082          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2083          */
2084         if (cmd->transport_complete_callback) {
2085                 sense_reason_t rc;
2086                 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2087                 bool zero_dl = !(cmd->data_length);
2088                 int post_ret = 0;
2089
2090                 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2091                 if (!rc && !post_ret) {
2092                         if (caw && zero_dl)
2093                                 goto queue_rsp;
2094
2095                         return;
2096                 } else if (rc) {
2097                         ret = transport_send_check_condition_and_sense(cmd,
2098                                                 rc, 0);
2099                         if (ret == -EAGAIN || ret == -ENOMEM)
2100                                 goto queue_full;
2101
2102                         transport_lun_remove_cmd(cmd);
2103                         transport_cmd_check_stop_to_fabric(cmd);
2104                         return;
2105                 }
2106         }
2107
2108 queue_rsp:
2109         switch (cmd->data_direction) {
2110         case DMA_FROM_DEVICE:
2111                 atomic_long_add(cmd->data_length,
2112                                 &cmd->se_lun->lun_stats.tx_data_octets);
2113                 /*
2114                  * Perform READ_STRIP of PI using software emulation when
2115                  * backend had PI enabled, if the transport will not be
2116                  * performing hardware READ_STRIP offload.
2117                  */
2118                 if (target_read_prot_action(cmd)) {
2119                         ret = transport_send_check_condition_and_sense(cmd,
2120                                                 cmd->pi_err, 0);
2121                         if (ret == -EAGAIN || ret == -ENOMEM)
2122                                 goto queue_full;
2123
2124                         transport_lun_remove_cmd(cmd);
2125                         transport_cmd_check_stop_to_fabric(cmd);
2126                         return;
2127                 }
2128
2129                 trace_target_cmd_complete(cmd);
2130                 ret = cmd->se_tfo->queue_data_in(cmd);
2131                 if (ret == -EAGAIN || ret == -ENOMEM)
2132                         goto queue_full;
2133                 break;
2134         case DMA_TO_DEVICE:
2135                 atomic_long_add(cmd->data_length,
2136                                 &cmd->se_lun->lun_stats.rx_data_octets);
2137                 /*
2138                  * Check if we need to send READ payload for BIDI-COMMAND
2139                  */
2140                 if (cmd->se_cmd_flags & SCF_BIDI) {
2141                         atomic_long_add(cmd->data_length,
2142                                         &cmd->se_lun->lun_stats.tx_data_octets);
2143                         ret = cmd->se_tfo->queue_data_in(cmd);
2144                         if (ret == -EAGAIN || ret == -ENOMEM)
2145                                 goto queue_full;
2146                         break;
2147                 }
2148                 /* Fall through for DMA_TO_DEVICE */
2149         case DMA_NONE:
2150                 trace_target_cmd_complete(cmd);
2151                 ret = cmd->se_tfo->queue_status(cmd);
2152                 if (ret == -EAGAIN || ret == -ENOMEM)
2153                         goto queue_full;
2154                 break;
2155         default:
2156                 break;
2157         }
2158
2159         transport_lun_remove_cmd(cmd);
2160         transport_cmd_check_stop_to_fabric(cmd);
2161         return;
2162
2163 queue_full:
2164         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2165                 " data_direction: %d\n", cmd, cmd->data_direction);
2166         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2167         transport_handle_queue_full(cmd, cmd->se_dev);
2168 }
2169
2170 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2171 {
2172         struct scatterlist *sg;
2173         int count;
2174
2175         for_each_sg(sgl, sg, nents, count)
2176                 __free_page(sg_page(sg));
2177
2178         kfree(sgl);
2179 }
2180
2181 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2182 {
2183         /*
2184          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2185          * emulation, and free + reset pointers if necessary..
2186          */
2187         if (!cmd->t_data_sg_orig)
2188                 return;
2189
2190         kfree(cmd->t_data_sg);
2191         cmd->t_data_sg = cmd->t_data_sg_orig;
2192         cmd->t_data_sg_orig = NULL;
2193         cmd->t_data_nents = cmd->t_data_nents_orig;
2194         cmd->t_data_nents_orig = 0;
2195 }
2196
2197 static inline void transport_free_pages(struct se_cmd *cmd)
2198 {
2199         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2200                 transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2201                 cmd->t_prot_sg = NULL;
2202                 cmd->t_prot_nents = 0;
2203         }
2204
2205         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2206                 /*
2207                  * Release special case READ buffer payload required for
2208                  * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2209                  */
2210                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2211                         transport_free_sgl(cmd->t_bidi_data_sg,
2212                                            cmd->t_bidi_data_nents);
2213                         cmd->t_bidi_data_sg = NULL;
2214                         cmd->t_bidi_data_nents = 0;
2215                 }
2216                 transport_reset_sgl_orig(cmd);
2217                 return;
2218         }
2219         transport_reset_sgl_orig(cmd);
2220
2221         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2222         cmd->t_data_sg = NULL;
2223         cmd->t_data_nents = 0;
2224
2225         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2226         cmd->t_bidi_data_sg = NULL;
2227         cmd->t_bidi_data_nents = 0;
2228 }
2229
2230 /**
2231  * transport_put_cmd - release a reference to a command
2232  * @cmd:       command to release
2233  *
2234  * This routine releases our reference to the command and frees it if possible.
2235  */
2236 static int transport_put_cmd(struct se_cmd *cmd)
2237 {
2238         BUG_ON(!cmd->se_tfo);
2239         /*
2240          * If this cmd has been setup with target_get_sess_cmd(), drop
2241          * the kref and call ->release_cmd() in kref callback.
2242          */
2243         return target_put_sess_cmd(cmd);
2244 }
2245
2246 void *transport_kmap_data_sg(struct se_cmd *cmd)
2247 {
2248         struct scatterlist *sg = cmd->t_data_sg;
2249         struct page **pages;
2250         int i;
2251
2252         /*
2253          * We need to take into account a possible offset here for fabrics like
2254          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2255          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2256          */
2257         if (!cmd->t_data_nents)
2258                 return NULL;
2259
2260         BUG_ON(!sg);
2261         if (cmd->t_data_nents == 1)
2262                 return kmap(sg_page(sg)) + sg->offset;
2263
2264         /* >1 page. use vmap */
2265         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2266         if (!pages)
2267                 return NULL;
2268
2269         /* convert sg[] to pages[] */
2270         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2271                 pages[i] = sg_page(sg);
2272         }
2273
2274         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2275         kfree(pages);
2276         if (!cmd->t_data_vmap)
2277                 return NULL;
2278
2279         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2280 }
2281 EXPORT_SYMBOL(transport_kmap_data_sg);
2282
2283 void transport_kunmap_data_sg(struct se_cmd *cmd)
2284 {
2285         if (!cmd->t_data_nents) {
2286                 return;
2287         } else if (cmd->t_data_nents == 1) {
2288                 kunmap(sg_page(cmd->t_data_sg));
2289                 return;
2290         }
2291
2292         vunmap(cmd->t_data_vmap);
2293         cmd->t_data_vmap = NULL;
2294 }
2295 EXPORT_SYMBOL(transport_kunmap_data_sg);
2296
2297 int
2298 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2299                  bool zero_page)
2300 {
2301         struct scatterlist *sg;
2302         struct page *page;
2303         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2304         unsigned int nent;
2305         int i = 0;
2306
2307         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2308         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2309         if (!sg)
2310                 return -ENOMEM;
2311
2312         sg_init_table(sg, nent);
2313
2314         while (length) {
2315                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2316                 page = alloc_page(GFP_KERNEL | zero_flag);
2317                 if (!page)
2318                         goto out;
2319
2320                 sg_set_page(&sg[i], page, page_len, 0);
2321                 length -= page_len;
2322                 i++;
2323         }
2324         *sgl = sg;
2325         *nents = nent;
2326         return 0;
2327
2328 out:
2329         while (i > 0) {
2330                 i--;
2331                 __free_page(sg_page(&sg[i]));
2332         }
2333         kfree(sg);
2334         return -ENOMEM;
2335 }
2336
2337 /*
2338  * Allocate any required resources to execute the command.  For writes we
2339  * might not have the payload yet, so notify the fabric via a call to
2340  * ->write_pending instead. Otherwise place it on the execution queue.
2341  */
2342 sense_reason_t
2343 transport_generic_new_cmd(struct se_cmd *cmd)
2344 {
2345         int ret = 0;
2346         bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2347
2348         if (cmd->prot_op != TARGET_PROT_NORMAL &&
2349             !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2350                 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2351                                        cmd->prot_length, true);
2352                 if (ret < 0)
2353                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2354         }
2355
2356         /*
2357          * Determine is the TCM fabric module has already allocated physical
2358          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2359          * beforehand.
2360          */
2361         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2362             cmd->data_length) {
2363
2364                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2365                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2366                         u32 bidi_length;
2367
2368                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2369                                 bidi_length = cmd->t_task_nolb *
2370                                               cmd->se_dev->dev_attrib.block_size;
2371                         else
2372                                 bidi_length = cmd->data_length;
2373
2374                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2375                                                &cmd->t_bidi_data_nents,
2376                                                bidi_length, zero_flag);
2377                         if (ret < 0)
2378                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2379                 }
2380
2381                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2382                                        cmd->data_length, zero_flag);
2383                 if (ret < 0)
2384                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2385         } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2386                     cmd->data_length) {
2387                 /*
2388                  * Special case for COMPARE_AND_WRITE with fabrics
2389                  * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2390                  */
2391                 u32 caw_length = cmd->t_task_nolb *
2392                                  cmd->se_dev->dev_attrib.block_size;
2393
2394                 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2395                                        &cmd->t_bidi_data_nents,
2396                                        caw_length, zero_flag);
2397                 if (ret < 0)
2398                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2399         }
2400         /*
2401          * If this command is not a write we can execute it right here,
2402          * for write buffers we need to notify the fabric driver first
2403          * and let it call back once the write buffers are ready.
2404          */
2405         target_add_to_state_list(cmd);
2406         if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2407                 target_execute_cmd(cmd);
2408                 return 0;
2409         }
2410         transport_cmd_check_stop(cmd, false, true);
2411
2412         ret = cmd->se_tfo->write_pending(cmd);
2413         if (ret == -EAGAIN || ret == -ENOMEM)
2414                 goto queue_full;
2415
2416         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2417         WARN_ON(ret);
2418
2419         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2420
2421 queue_full:
2422         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2423         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2424         transport_handle_queue_full(cmd, cmd->se_dev);
2425         return 0;
2426 }
2427 EXPORT_SYMBOL(transport_generic_new_cmd);
2428
2429 static void transport_write_pending_qf(struct se_cmd *cmd)
2430 {
2431         int ret;
2432
2433         ret = cmd->se_tfo->write_pending(cmd);
2434         if (ret == -EAGAIN || ret == -ENOMEM) {
2435                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2436                          cmd);
2437                 transport_handle_queue_full(cmd, cmd->se_dev);
2438         }
2439 }
2440
2441 static bool
2442 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2443                            unsigned long *flags);
2444
2445 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2446 {
2447         unsigned long flags;
2448
2449         spin_lock_irqsave(&cmd->t_state_lock, flags);
2450         __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2451         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2452 }
2453
2454 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2455 {
2456         int ret = 0;
2457         bool aborted = false, tas = false;
2458
2459         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2460                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2461                         target_wait_free_cmd(cmd, &aborted, &tas);
2462
2463                 if (!aborted || tas)
2464                         ret = transport_put_cmd(cmd);
2465         } else {
2466                 if (wait_for_tasks)
2467                         target_wait_free_cmd(cmd, &aborted, &tas);
2468                 /*
2469                  * Handle WRITE failure case where transport_generic_new_cmd()
2470                  * has already added se_cmd to state_list, but fabric has
2471                  * failed command before I/O submission.
2472                  */
2473                 if (cmd->state_active)
2474                         target_remove_from_state_list(cmd);
2475
2476                 if (cmd->se_lun)
2477                         transport_lun_remove_cmd(cmd);
2478
2479                 if (!aborted || tas)
2480                         ret = transport_put_cmd(cmd);
2481         }
2482         /*
2483          * If the task has been internally aborted due to TMR ABORT_TASK
2484          * or LUN_RESET, target_core_tmr.c is responsible for performing
2485          * the remaining calls to target_put_sess_cmd(), and not the
2486          * callers of this function.
2487          */
2488         if (aborted) {
2489                 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2490                 wait_for_completion(&cmd->cmd_wait_comp);
2491                 cmd->se_tfo->release_cmd(cmd);
2492                 ret = 1;
2493         }
2494         return ret;
2495 }
2496 EXPORT_SYMBOL(transport_generic_free_cmd);
2497
2498 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2499  * @se_cmd:     command descriptor to add
2500  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2501  */
2502 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2503 {
2504         struct se_session *se_sess = se_cmd->se_sess;
2505         unsigned long flags;
2506         int ret = 0;
2507
2508         /*
2509          * Add a second kref if the fabric caller is expecting to handle
2510          * fabric acknowledgement that requires two target_put_sess_cmd()
2511          * invocations before se_cmd descriptor release.
2512          */
2513         if (ack_kref) {
2514                 kref_get(&se_cmd->cmd_kref);
2515                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2516         }
2517
2518         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2519         if (se_sess->sess_tearing_down) {
2520                 ret = -ESHUTDOWN;
2521                 goto out;
2522         }
2523         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2524 out:
2525         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2526
2527         if (ret && ack_kref)
2528                 target_put_sess_cmd(se_cmd);
2529
2530         return ret;
2531 }
2532 EXPORT_SYMBOL(target_get_sess_cmd);
2533
2534 static void target_free_cmd_mem(struct se_cmd *cmd)
2535 {
2536         transport_free_pages(cmd);
2537
2538         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2539                 core_tmr_release_req(cmd->se_tmr_req);
2540         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2541                 kfree(cmd->t_task_cdb);
2542 }
2543
2544 static void target_release_cmd_kref(struct kref *kref)
2545 {
2546         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2547         struct se_session *se_sess = se_cmd->se_sess;
2548         unsigned long flags;
2549         bool fabric_stop;
2550
2551         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2552
2553         spin_lock(&se_cmd->t_state_lock);
2554         fabric_stop = (se_cmd->transport_state & CMD_T_FABRIC_STOP) &&
2555                       (se_cmd->transport_state & CMD_T_ABORTED);
2556         spin_unlock(&se_cmd->t_state_lock);
2557
2558         if (se_cmd->cmd_wait_set || fabric_stop) {
2559                 list_del_init(&se_cmd->se_cmd_list);
2560                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2561                 target_free_cmd_mem(se_cmd);
2562                 complete(&se_cmd->cmd_wait_comp);
2563                 return;
2564         }
2565         list_del_init(&se_cmd->se_cmd_list);
2566         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2567
2568         target_free_cmd_mem(se_cmd);
2569         se_cmd->se_tfo->release_cmd(se_cmd);
2570 }
2571
2572 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2573  * @se_cmd:     command descriptor to drop
2574  */
2575 int target_put_sess_cmd(struct se_cmd *se_cmd)
2576 {
2577         struct se_session *se_sess = se_cmd->se_sess;
2578
2579         if (!se_sess) {
2580                 target_free_cmd_mem(se_cmd);
2581                 se_cmd->se_tfo->release_cmd(se_cmd);
2582                 return 1;
2583         }
2584         return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2585 }
2586 EXPORT_SYMBOL(target_put_sess_cmd);
2587
2588 /* target_sess_cmd_list_set_waiting - Flag all commands in
2589  *         sess_cmd_list to complete cmd_wait_comp.  Set
2590  *         sess_tearing_down so no more commands are queued.
2591  * @se_sess:    session to flag
2592  */
2593 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2594 {
2595         struct se_cmd *se_cmd;
2596         unsigned long flags;
2597         int rc;
2598
2599         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2600         if (se_sess->sess_tearing_down) {
2601                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2602                 return;
2603         }
2604         se_sess->sess_tearing_down = 1;
2605         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2606
2607         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list) {
2608                 rc = kref_get_unless_zero(&se_cmd->cmd_kref);
2609                 if (rc) {
2610                         se_cmd->cmd_wait_set = 1;
2611                         spin_lock(&se_cmd->t_state_lock);
2612                         se_cmd->transport_state |= CMD_T_FABRIC_STOP;
2613                         spin_unlock(&se_cmd->t_state_lock);
2614                 }
2615         }
2616
2617         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2618 }
2619 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2620
2621 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2622  * @se_sess:    session to wait for active I/O
2623  */
2624 void target_wait_for_sess_cmds(struct se_session *se_sess)
2625 {
2626         struct se_cmd *se_cmd, *tmp_cmd;
2627         unsigned long flags;
2628         bool tas;
2629
2630         list_for_each_entry_safe(se_cmd, tmp_cmd,
2631                                 &se_sess->sess_wait_list, se_cmd_list) {
2632                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2633                         " %d\n", se_cmd, se_cmd->t_state,
2634                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2635
2636                 spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2637                 tas = (se_cmd->transport_state & CMD_T_TAS);
2638                 spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2639
2640                 if (!target_put_sess_cmd(se_cmd)) {
2641                         if (tas)
2642                                 target_put_sess_cmd(se_cmd);
2643                 }
2644
2645                 wait_for_completion(&se_cmd->cmd_wait_comp);
2646                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2647                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2648                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2649
2650                 se_cmd->se_tfo->release_cmd(se_cmd);
2651         }
2652
2653         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2654         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2655         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2656
2657 }
2658 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2659
2660 void transport_clear_lun_ref(struct se_lun *lun)
2661 {
2662         percpu_ref_kill(&lun->lun_ref);
2663         wait_for_completion(&lun->lun_ref_comp);
2664 }
2665
2666 static bool
2667 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2668                            bool *aborted, bool *tas, unsigned long *flags)
2669         __releases(&cmd->t_state_lock)
2670         __acquires(&cmd->t_state_lock)
2671 {
2672
2673         assert_spin_locked(&cmd->t_state_lock);
2674         WARN_ON_ONCE(!irqs_disabled());
2675
2676         if (fabric_stop)
2677                 cmd->transport_state |= CMD_T_FABRIC_STOP;
2678
2679         if (cmd->transport_state & CMD_T_ABORTED)
2680                 *aborted = true;
2681
2682         if (cmd->transport_state & CMD_T_TAS)
2683                 *tas = true;
2684
2685         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2686             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2687                 return false;
2688
2689         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2690             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2691                 return false;
2692
2693         if (!(cmd->transport_state & CMD_T_ACTIVE))
2694                 return false;
2695
2696         if (fabric_stop && *aborted)
2697                 return false;
2698
2699         cmd->transport_state |= CMD_T_STOP;
2700
2701         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08llx i_state: %d,"
2702                  " t_state: %d, CMD_T_STOP\n", cmd, cmd->tag,
2703                  cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2704
2705         spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2706
2707         wait_for_completion(&cmd->t_transport_stop_comp);
2708
2709         spin_lock_irqsave(&cmd->t_state_lock, *flags);
2710         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2711
2712         pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
2713                  "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
2714
2715         return true;
2716 }
2717
2718 /**
2719  * transport_wait_for_tasks - wait for completion to occur
2720  * @cmd:        command to wait
2721  *
2722  * Called from frontend fabric context to wait for storage engine
2723  * to pause and/or release frontend generated struct se_cmd.
2724  */
2725 bool transport_wait_for_tasks(struct se_cmd *cmd)
2726 {
2727         unsigned long flags;
2728         bool ret, aborted = false, tas = false;
2729
2730         spin_lock_irqsave(&cmd->t_state_lock, flags);
2731         ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
2732         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2733
2734         return ret;
2735 }
2736 EXPORT_SYMBOL(transport_wait_for_tasks);
2737
2738 struct sense_info {
2739         u8 key;
2740         u8 asc;
2741         u8 ascq;
2742         bool add_sector_info;
2743 };
2744
2745 static const struct sense_info sense_info_table[] = {
2746         [TCM_NO_SENSE] = {
2747                 .key = NOT_READY
2748         },
2749         [TCM_NON_EXISTENT_LUN] = {
2750                 .key = ILLEGAL_REQUEST,
2751                 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
2752         },
2753         [TCM_UNSUPPORTED_SCSI_OPCODE] = {
2754                 .key = ILLEGAL_REQUEST,
2755                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2756         },
2757         [TCM_SECTOR_COUNT_TOO_MANY] = {
2758                 .key = ILLEGAL_REQUEST,
2759                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2760         },
2761         [TCM_UNKNOWN_MODE_PAGE] = {
2762                 .key = ILLEGAL_REQUEST,
2763                 .asc = 0x24, /* INVALID FIELD IN CDB */
2764         },
2765         [TCM_CHECK_CONDITION_ABORT_CMD] = {
2766                 .key = ABORTED_COMMAND,
2767                 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
2768                 .ascq = 0x03,
2769         },
2770         [TCM_INCORRECT_AMOUNT_OF_DATA] = {
2771                 .key = ABORTED_COMMAND,
2772                 .asc = 0x0c, /* WRITE ERROR */
2773                 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
2774         },
2775         [TCM_INVALID_CDB_FIELD] = {
2776                 .key = ILLEGAL_REQUEST,
2777                 .asc = 0x24, /* INVALID FIELD IN CDB */
2778         },
2779         [TCM_INVALID_PARAMETER_LIST] = {
2780                 .key = ILLEGAL_REQUEST,
2781                 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
2782         },
2783         [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
2784                 .key = ILLEGAL_REQUEST,
2785                 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
2786         },
2787         [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
2788                 .key = ILLEGAL_REQUEST,
2789                 .asc = 0x0c, /* WRITE ERROR */
2790                 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
2791         },
2792         [TCM_SERVICE_CRC_ERROR] = {
2793                 .key = ABORTED_COMMAND,
2794                 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
2795                 .ascq = 0x05, /* N/A */
2796         },
2797         [TCM_SNACK_REJECTED] = {
2798                 .key = ABORTED_COMMAND,
2799                 .asc = 0x11, /* READ ERROR */
2800                 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
2801         },
2802         [TCM_WRITE_PROTECTED] = {
2803                 .key = DATA_PROTECT,
2804                 .asc = 0x27, /* WRITE PROTECTED */
2805         },
2806         [TCM_ADDRESS_OUT_OF_RANGE] = {
2807                 .key = ILLEGAL_REQUEST,
2808                 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2809         },
2810         [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
2811                 .key = UNIT_ATTENTION,
2812         },
2813         [TCM_CHECK_CONDITION_NOT_READY] = {
2814                 .key = NOT_READY,
2815         },
2816         [TCM_MISCOMPARE_VERIFY] = {
2817                 .key = MISCOMPARE,
2818                 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
2819                 .ascq = 0x00,
2820         },
2821         [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
2822                 .key = ABORTED_COMMAND,
2823                 .asc = 0x10,
2824                 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
2825                 .add_sector_info = true,
2826         },
2827         [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
2828                 .key = ABORTED_COMMAND,
2829                 .asc = 0x10,
2830                 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2831                 .add_sector_info = true,
2832         },
2833         [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
2834                 .key = ABORTED_COMMAND,
2835                 .asc = 0x10,
2836                 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2837                 .add_sector_info = true,
2838         },
2839         [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
2840                 .key = COPY_ABORTED,
2841                 .asc = 0x0d,
2842                 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
2843
2844         },
2845         [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
2846                 /*
2847                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2848                  * Solaris initiators.  Returning NOT READY instead means the
2849                  * operations will be retried a finite number of times and we
2850                  * can survive intermittent errors.
2851                  */
2852                 .key = NOT_READY,
2853                 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
2854         },
2855 };
2856
2857 static int translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
2858 {
2859         const struct sense_info *si;
2860         u8 *buffer = cmd->sense_buffer;
2861         int r = (__force int)reason;
2862         u8 asc, ascq;
2863         bool desc_format = target_sense_desc_format(cmd->se_dev);
2864
2865         if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
2866                 si = &sense_info_table[r];
2867         else
2868                 si = &sense_info_table[(__force int)
2869                                        TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
2870
2871         if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
2872                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2873                 WARN_ON_ONCE(asc == 0);
2874         } else if (si->asc == 0) {
2875                 WARN_ON_ONCE(cmd->scsi_asc == 0);
2876                 asc = cmd->scsi_asc;
2877                 ascq = cmd->scsi_ascq;
2878         } else {
2879                 asc = si->asc;
2880                 ascq = si->ascq;
2881         }
2882
2883         scsi_build_sense_buffer(desc_format, buffer, si->key, asc, ascq);
2884         if (si->add_sector_info)
2885                 return scsi_set_sense_information(buffer,
2886                                                   cmd->scsi_sense_length,
2887                                                   cmd->bad_sector);
2888
2889         return 0;
2890 }
2891
2892 int
2893 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2894                 sense_reason_t reason, int from_transport)
2895 {
2896         unsigned long flags;
2897
2898         spin_lock_irqsave(&cmd->t_state_lock, flags);
2899         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2900                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2901                 return 0;
2902         }
2903         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2904         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2905
2906         if (!from_transport) {
2907                 int rc;
2908
2909                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2910                 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2911                 cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2912                 rc = translate_sense_reason(cmd, reason);
2913                 if (rc)
2914                         return rc;
2915         }
2916
2917         trace_target_cmd_complete(cmd);
2918         return cmd->se_tfo->queue_status(cmd);
2919 }
2920 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2921
2922 static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2923         __releases(&cmd->t_state_lock)
2924         __acquires(&cmd->t_state_lock)
2925 {
2926         assert_spin_locked(&cmd->t_state_lock);
2927         WARN_ON_ONCE(!irqs_disabled());
2928
2929         if (!(cmd->transport_state & CMD_T_ABORTED))
2930                 return 0;
2931         /*
2932          * If cmd has been aborted but either no status is to be sent or it has
2933          * already been sent, just return
2934          */
2935         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
2936                 if (send_status)
2937                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2938                 return 1;
2939         }
2940
2941         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
2942                 " 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);
2943
2944         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2945         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2946         trace_target_cmd_complete(cmd);
2947
2948         spin_unlock_irq(&cmd->t_state_lock);
2949         cmd->se_tfo->queue_status(cmd);
2950         spin_lock_irq(&cmd->t_state_lock);
2951
2952         return 1;
2953 }
2954
2955 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2956 {
2957         int ret;
2958
2959         spin_lock_irq(&cmd->t_state_lock);
2960         ret = __transport_check_aborted_status(cmd, send_status);
2961         spin_unlock_irq(&cmd->t_state_lock);
2962
2963         return ret;
2964 }
2965 EXPORT_SYMBOL(transport_check_aborted_status);
2966
2967 void transport_send_task_abort(struct se_cmd *cmd)
2968 {
2969         unsigned long flags;
2970
2971         spin_lock_irqsave(&cmd->t_state_lock, flags);
2972         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2973                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2974                 return;
2975         }
2976         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2977
2978         /*
2979          * If there are still expected incoming fabric WRITEs, we wait
2980          * until until they have completed before sending a TASK_ABORTED
2981          * response.  This response with TASK_ABORTED status will be
2982          * queued back to fabric module by transport_check_aborted_status().
2983          */
2984         if (cmd->data_direction == DMA_TO_DEVICE) {
2985                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2986                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2987                         if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) {
2988                                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2989                                 goto send_abort;
2990                         }
2991                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2992                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2993                         return;
2994                 }
2995         }
2996 send_abort:
2997         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2998
2999         transport_lun_remove_cmd(cmd);
3000
3001         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
3002                  cmd->t_task_cdb[0], cmd->tag);
3003
3004         trace_target_cmd_complete(cmd);
3005         cmd->se_tfo->queue_status(cmd);
3006 }
3007
3008 static void target_tmr_work(struct work_struct *work)
3009 {
3010         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3011         struct se_device *dev = cmd->se_dev;
3012         struct se_tmr_req *tmr = cmd->se_tmr_req;
3013         unsigned long flags;
3014         int ret;
3015
3016         spin_lock_irqsave(&cmd->t_state_lock, flags);
3017         if (cmd->transport_state & CMD_T_ABORTED) {
3018                 tmr->response = TMR_FUNCTION_REJECTED;
3019                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3020                 goto check_stop;
3021         }
3022         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3023
3024         switch (tmr->function) {
3025         case TMR_ABORT_TASK:
3026                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3027                 break;
3028         case TMR_ABORT_TASK_SET:
3029         case TMR_CLEAR_ACA:
3030         case TMR_CLEAR_TASK_SET:
3031                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3032                 break;
3033         case TMR_LUN_RESET:
3034                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3035                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3036                                          TMR_FUNCTION_REJECTED;
3037                 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3038                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3039                                                cmd->orig_fe_lun, 0x29,
3040                                                ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3041                 }
3042                 break;
3043         case TMR_TARGET_WARM_RESET:
3044                 tmr->response = TMR_FUNCTION_REJECTED;
3045                 break;
3046         case TMR_TARGET_COLD_RESET:
3047                 tmr->response = TMR_FUNCTION_REJECTED;
3048                 break;
3049         default:
3050                 pr_err("Uknown TMR function: 0x%02x.\n",
3051                                 tmr->function);
3052                 tmr->response = TMR_FUNCTION_REJECTED;
3053                 break;
3054         }
3055
3056         spin_lock_irqsave(&cmd->t_state_lock, flags);
3057         if (cmd->transport_state & CMD_T_ABORTED) {
3058                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3059                 goto check_stop;
3060         }
3061         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3062
3063         cmd->se_tfo->queue_tm_rsp(cmd);
3064
3065 check_stop:
3066         transport_cmd_check_stop_to_fabric(cmd);
3067 }
3068
3069 int transport_generic_handle_tmr(
3070         struct se_cmd *cmd)
3071 {
3072         unsigned long flags;
3073         bool aborted = false;
3074
3075         spin_lock_irqsave(&cmd->t_state_lock, flags);
3076         if (cmd->transport_state & CMD_T_ABORTED) {
3077                 aborted = true;
3078         } else {
3079                 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3080                 cmd->transport_state |= CMD_T_ACTIVE;
3081         }
3082         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3083
3084         if (aborted) {
3085                 pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d"
3086                         "ref_tag: %llu tag: %llu\n", cmd->se_tmr_req->function,
3087                         cmd->se_tmr_req->ref_task_tag, cmd->tag);
3088                 transport_cmd_check_stop_to_fabric(cmd);
3089                 return 0;
3090         }
3091
3092         INIT_WORK(&cmd->work, target_tmr_work);
3093         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3094         return 0;
3095 }
3096 EXPORT_SYMBOL(transport_generic_handle_tmr);
3097
3098 bool
3099 target_check_wce(struct se_device *dev)
3100 {
3101         bool wce = false;
3102
3103         if (dev->transport->get_write_cache)
3104                 wce = dev->transport->get_write_cache(dev);
3105         else if (dev->dev_attrib.emulate_write_cache > 0)
3106                 wce = true;
3107
3108         return wce;
3109 }
3110
3111 bool
3112 target_check_fua(struct se_device *dev)
3113 {
3114         return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3115 }