drivers/target/target_core_transport.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*******************************************************************************
   3  * Filename:  target_core_transport.c
   4  *
   5  * This file contains the Generic Target Engine Core.
   6  *
   7  * (c) Copyright 2002-2013 Datera, Inc.
   8  *
   9  * Nicholas A. Bellinger <[email protected]>
  10  *
  11  ******************************************************************************/
  12
  13 #include <linux/net.h>
  14 #include <linux/delay.h>
  15 #include <linux/string.h>
  16 #include <linux/timer.h>
  17 #include <linux/slab.h>
  18 #include <linux/spinlock.h>
  19 #include <linux/kthread.h>
  20 #include <linux/in.h>
  21 #include <linux/cdrom.h>
  22 #include <linux/module.h>
  23 #include <linux/ratelimit.h>
  24 #include <linux/vmalloc.h>
  25 #include <asm/unaligned.h>
  26 #include <net/sock.h>
  27 #include <net/tcp.h>
  28 #include <scsi/scsi_proto.h>
  29 #include <scsi/scsi_common.h>
  30
  31 #include <target/target_core_base.h>
  32 #include <target/target_core_backend.h>
  33 #include <target/target_core_fabric.h>
  34
  35 #include "target_core_internal.h"
  36 #include "target_core_alua.h"
  37 #include "target_core_pr.h"
  38 #include "target_core_ua.h"
  39
  40 #define CREATE_TRACE_POINTS
  41 #include <trace/events/target.h>
  42
  43 static struct workqueue_struct *target_completion_wq;
  44 static struct workqueue_struct *target_submission_wq;
  45 static struct kmem_cache *se_sess_cache;
  46 struct kmem_cache *se_ua_cache;
  47 struct kmem_cache *t10_pr_reg_cache;
  48 struct kmem_cache *t10_alua_lu_gp_cache;
  49 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  50 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  51 struct kmem_cache *t10_alua_lba_map_cache;
  52 struct kmem_cache *t10_alua_lba_map_mem_cache;
  53
  54 static void transport_complete_task_attr(struct se_cmd *cmd);
  55 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason);
  56 static void transport_handle_queue_full(struct se_cmd *cmd,
  57                 struct se_device *dev, int err, bool write_pending);
  58 static void target_complete_ok_work(struct work_struct *work);
  59
  60 int init_se_kmem_caches(void)
  61 {
  62         se_sess_cache = kmem_cache_create("se_sess_cache",
  63                         sizeof(struct se_session), __alignof__(struct se_session),
  64                         0, NULL);
  65         if (!se_sess_cache) {
  66                 pr_err("kmem_cache_create() for struct se_session"
  67                                 " failed\n");
  68                 goto out;
  69         }
  70         se_ua_cache = kmem_cache_create("se_ua_cache",
  71                         sizeof(struct se_ua), __alignof__(struct se_ua),
  72                         0, NULL);
  73         if (!se_ua_cache) {
  74                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  75                 goto out_free_sess_cache;
  76         }
  77         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  78                         sizeof(struct t10_pr_registration),
  79                         __alignof__(struct t10_pr_registration), 0, NULL);
  80         if (!t10_pr_reg_cache) {
  81                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  82                                 " failed\n");
  83                 goto out_free_ua_cache;
  84         }
  85         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
  86                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
  87                         0, NULL);
  88         if (!t10_alua_lu_gp_cache) {
  89                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
  90                                 " failed\n");
  91                 goto out_free_pr_reg_cache;
  92         }
  93         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
  94                         sizeof(struct t10_alua_lu_gp_member),
  95                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
  96         if (!t10_alua_lu_gp_mem_cache) {
  97                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
  98                                 "cache failed\n");
  99                 goto out_free_lu_gp_cache;
 100         }
 101         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 102                         sizeof(struct t10_alua_tg_pt_gp),
 103                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 104         if (!t10_alua_tg_pt_gp_cache) {
 105                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 106                                 "cache failed\n");
 107                 goto out_free_lu_gp_mem_cache;
 108         }
 109         t10_alua_lba_map_cache = kmem_cache_create(
 110                         "t10_alua_lba_map_cache",
 111                         sizeof(struct t10_alua_lba_map),
 112                         __alignof__(struct t10_alua_lba_map), 0, NULL);
 113         if (!t10_alua_lba_map_cache) {
 114                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
 115                                 "cache failed\n");
 116                 goto out_free_tg_pt_gp_cache;
 117         }
 118         t10_alua_lba_map_mem_cache = kmem_cache_create(
 119                         "t10_alua_lba_map_mem_cache",
 120                         sizeof(struct t10_alua_lba_map_member),
 121                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
 122         if (!t10_alua_lba_map_mem_cache) {
 123                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
 124                                 "cache failed\n");
 125                 goto out_free_lba_map_cache;
 126         }
 127
 128         target_completion_wq = alloc_workqueue("target_completion",
 129                                                WQ_MEM_RECLAIM, 0);
 130         if (!target_completion_wq)
 131                 goto out_free_lba_map_mem_cache;
 132
 133         target_submission_wq = alloc_workqueue("target_submission",
 134                                                WQ_MEM_RECLAIM, 0);
 135         if (!target_submission_wq)
 136                 goto out_free_completion_wq;
 137
 138         return 0;
 139
 140 out_free_completion_wq:
 141         destroy_workqueue(target_completion_wq);
 142 out_free_lba_map_mem_cache:
 143         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 144 out_free_lba_map_cache:
 145         kmem_cache_destroy(t10_alua_lba_map_cache);
 146 out_free_tg_pt_gp_cache:
 147         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 148 out_free_lu_gp_mem_cache:
 149         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 150 out_free_lu_gp_cache:
 151         kmem_cache_destroy(t10_alua_lu_gp_cache);
 152 out_free_pr_reg_cache:
 153         kmem_cache_destroy(t10_pr_reg_cache);
 154 out_free_ua_cache:
 155         kmem_cache_destroy(se_ua_cache);
 156 out_free_sess_cache:
 157         kmem_cache_destroy(se_sess_cache);
 158 out:
 159         return -ENOMEM;
 160 }
 161
 162 void release_se_kmem_caches(void)
 163 {
 164         destroy_workqueue(target_submission_wq);
 165         destroy_workqueue(target_completion_wq);
 166         kmem_cache_destroy(se_sess_cache);
 167         kmem_cache_destroy(se_ua_cache);
 168         kmem_cache_destroy(t10_pr_reg_cache);
 169         kmem_cache_destroy(t10_alua_lu_gp_cache);
 170         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 171         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 172         kmem_cache_destroy(t10_alua_lba_map_cache);
 173         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 174 }
 175
 176 /* This code ensures unique mib indexes are handed out. */
 177 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 178 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 179
 180 /*
 181  * Allocate a new row index for the entry type specified
 182  */
 183 u32 scsi_get_new_index(scsi_index_t type)
 184 {
 185         u32 new_index;
 186
 187         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 188
 189         spin_lock(&scsi_mib_index_lock);
 190         new_index = ++scsi_mib_index[type];
 191         spin_unlock(&scsi_mib_index_lock);
 192
 193         return new_index;
 194 }
 195
 196 void transport_subsystem_check_init(void)
 197 {
 198         int ret;
 199         static int sub_api_initialized;
 200
 201         if (sub_api_initialized)
 202                 return;
 203
 204         ret = IS_ENABLED(CONFIG_TCM_IBLOCK) && request_module("target_core_iblock");
 205         if (ret != 0)
 206                 pr_err("Unable to load target_core_iblock\n");
 207
 208         ret = IS_ENABLED(CONFIG_TCM_FILEIO) && request_module("target_core_file");
 209         if (ret != 0)
 210                 pr_err("Unable to load target_core_file\n");
 211
 212         ret = IS_ENABLED(CONFIG_TCM_PSCSI) && request_module("target_core_pscsi");
 213         if (ret != 0)
 214                 pr_err("Unable to load target_core_pscsi\n");
 215
 216         ret = IS_ENABLED(CONFIG_TCM_USER2) && request_module("target_core_user");
 217         if (ret != 0)
 218                 pr_err("Unable to load target_core_user\n");
 219
 220         sub_api_initialized = 1;
 221 }
 222
 223 static void target_release_sess_cmd_refcnt(struct percpu_ref *ref)
 224 {
 225         struct se_session *sess = container_of(ref, typeof(*sess), cmd_count);
 226
 227         wake_up(&sess->cmd_count_wq);
 228 }
 229
 230 /**
 231  * transport_init_session - initialize a session object
 232  * @se_sess: Session object pointer.
 233  *
 234  * The caller must have zero-initialized @se_sess before calling this function.
 235  */
 236 int transport_init_session(struct se_session *se_sess)
 237 {
 238         INIT_LIST_HEAD(&se_sess->sess_list);
 239         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 240         spin_lock_init(&se_sess->sess_cmd_lock);
 241         init_waitqueue_head(&se_sess->cmd_count_wq);
 242         init_completion(&se_sess->stop_done);
 243         atomic_set(&se_sess->stopped, 0);
 244         return percpu_ref_init(&se_sess->cmd_count,
 245                                target_release_sess_cmd_refcnt, 0, GFP_KERNEL);
 246 }
 247 EXPORT_SYMBOL(transport_init_session);
 248
 249 void transport_uninit_session(struct se_session *se_sess)
 250 {
 251         /*
 252          * Drivers like iscsi and loop do not call target_stop_session
 253          * during session shutdown so we have to drop the ref taken at init
 254          * time here.
 255          */
 256         if (!atomic_read(&se_sess->stopped))
 257                 percpu_ref_put(&se_sess->cmd_count);
 258
 259         percpu_ref_exit(&se_sess->cmd_count);
 260 }
 261
 262 /**
 263  * transport_alloc_session - allocate a session object and initialize it
 264  * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
 265  */
 266 struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
 267 {
 268         struct se_session *se_sess;
 269         int ret;
 270
 271         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 272         if (!se_sess) {
 273                 pr_err("Unable to allocate struct se_session from"
 274                                 " se_sess_cache\n");
 275                 return ERR_PTR(-ENOMEM);
 276         }
 277         ret = transport_init_session(se_sess);
 278         if (ret < 0) {
 279                 kmem_cache_free(se_sess_cache, se_sess);
 280                 return ERR_PTR(ret);
 281         }
 282         se_sess->sup_prot_ops = sup_prot_ops;
 283
 284         return se_sess;
 285 }
 286 EXPORT_SYMBOL(transport_alloc_session);
 287
 288 /**
 289  * transport_alloc_session_tags - allocate target driver private data
 290  * @se_sess:  Session pointer.
 291  * @tag_num:  Maximum number of in-flight commands between initiator and target.
 292  * @tag_size: Size in bytes of the private data a target driver associates with
 293  *            each command.
 294  */
 295 int transport_alloc_session_tags(struct se_session *se_sess,
 296                                  unsigned int tag_num, unsigned int tag_size)
 297 {
 298         int rc;
 299
 300         se_sess->sess_cmd_map = kvcalloc(tag_size, tag_num,
 301                                          GFP_KERNEL | __GFP_RETRY_MAYFAIL);
 302         if (!se_sess->sess_cmd_map) {
 303                 pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 304                 return -ENOMEM;
 305         }
 306
 307         rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
 308                         false, GFP_KERNEL, NUMA_NO_NODE);
 309         if (rc < 0) {
 310                 pr_err("Unable to init se_sess->sess_tag_pool,"
 311                         " tag_num: %u\n", tag_num);
 312                 kvfree(se_sess->sess_cmd_map);
 313                 se_sess->sess_cmd_map = NULL;
 314                 return -ENOMEM;
 315         }
 316
 317         return 0;
 318 }
 319 EXPORT_SYMBOL(transport_alloc_session_tags);
 320
 321 /**
 322  * transport_init_session_tags - allocate a session and target driver private data
 323  * @tag_num:  Maximum number of in-flight commands between initiator and target.
 324  * @tag_size: Size in bytes of the private data a target driver associates with
 325  *            each command.
 326  * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
 327  */
 328 static struct se_session *
 329 transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
 330                             enum target_prot_op sup_prot_ops)
 331 {
 332         struct se_session *se_sess;
 333         int rc;
 334
 335         if (tag_num != 0 && !tag_size) {
 336                 pr_err("init_session_tags called with percpu-ida tag_num:"
 337                        " %u, but zero tag_size\n", tag_num);
 338                 return ERR_PTR(-EINVAL);
 339         }
 340         if (!tag_num && tag_size) {
 341                 pr_err("init_session_tags called with percpu-ida tag_size:"
 342                        " %u, but zero tag_num\n", tag_size);
 343                 return ERR_PTR(-EINVAL);
 344         }
 345
 346         se_sess = transport_alloc_session(sup_prot_ops);
 347         if (IS_ERR(se_sess))
 348                 return se_sess;
 349
 350         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 351         if (rc < 0) {
 352                 transport_free_session(se_sess);
 353                 return ERR_PTR(-ENOMEM);
 354         }
 355
 356         return se_sess;
 357 }
 358
 359 /*
 360  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 361  */
 362 void __transport_register_session(
 363         struct se_portal_group *se_tpg,
 364         struct se_node_acl *se_nacl,
 365         struct se_session *se_sess,
 366         void *fabric_sess_ptr)
 367 {
 368         const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
 369         unsigned char buf[PR_REG_ISID_LEN];
 370         unsigned long flags;
 371
 372         se_sess->se_tpg = se_tpg;
 373         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 374         /*
 375          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 376          *
 377          * Only set for struct se_session's that will actually be moving I/O.
 378          * eg: *NOT* discovery sessions.
 379          */
 380         if (se_nacl) {
 381                 /*
 382                  *
 383                  * Determine if fabric allows for T10-PI feature bits exposed to
 384                  * initiators for device backends with !dev->dev_attrib.pi_prot_type.
 385                  *
 386                  * If so, then always save prot_type on a per se_node_acl node
 387                  * basis and re-instate the previous sess_prot_type to avoid
 388                  * disabling PI from below any previously initiator side
 389                  * registered LUNs.
 390                  */
 391                 if (se_nacl->saved_prot_type)
 392                         se_sess->sess_prot_type = se_nacl->saved_prot_type;
 393                 else if (tfo->tpg_check_prot_fabric_only)
 394                         se_sess->sess_prot_type = se_nacl->saved_prot_type =
 395                                         tfo->tpg_check_prot_fabric_only(se_tpg);
 396                 /*
 397                  * If the fabric module supports an ISID based TransportID,
 398                  * save this value in binary from the fabric I_T Nexus now.
 399                  */
 400                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 401                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 402                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 403                                         &buf[0], PR_REG_ISID_LEN);
 404                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 405                 }
 406
 407                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 408                 /*
 409                  * The se_nacl->nacl_sess pointer will be set to the
 410                  * last active I_T Nexus for each struct se_node_acl.
 411                  */
 412                 se_nacl->nacl_sess = se_sess;
 413
 414                 list_add_tail(&se_sess->sess_acl_list,
 415                               &se_nacl->acl_sess_list);
 416                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 417         }
 418         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 419
 420         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 421                 se_tpg->se_tpg_tfo->fabric_name, se_sess->fabric_sess_ptr);
 422 }
 423 EXPORT_SYMBOL(__transport_register_session);
 424
 425 void transport_register_session(
 426         struct se_portal_group *se_tpg,
 427         struct se_node_acl *se_nacl,
 428         struct se_session *se_sess,
 429         void *fabric_sess_ptr)
 430 {
 431         unsigned long flags;
 432
 433         spin_lock_irqsave(&se_tpg->session_lock, flags);
 434         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 435         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 436 }
 437 EXPORT_SYMBOL(transport_register_session);
 438
 439 struct se_session *
 440 target_setup_session(struct se_portal_group *tpg,
 441                      unsigned int tag_num, unsigned int tag_size,
 442                      enum target_prot_op prot_op,
 443                      const char *initiatorname, void *private,
 444                      int (*callback)(struct se_portal_group *,
 445                                      struct se_session *, void *))
 446 {
 447         struct se_session *sess;
 448
 449         /*
 450          * If the fabric driver is using percpu-ida based pre allocation
 451          * of I/O descriptor tags, go ahead and perform that setup now..
 452          */
 453         if (tag_num != 0)
 454                 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
 455         else
 456                 sess = transport_alloc_session(prot_op);
 457
 458         if (IS_ERR(sess))
 459                 return sess;
 460
 461         sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
 462                                         (unsigned char *)initiatorname);
 463         if (!sess->se_node_acl) {
 464                 transport_free_session(sess);
 465                 return ERR_PTR(-EACCES);
 466         }
 467         /*
 468          * Go ahead and perform any remaining fabric setup that is
 469          * required before transport_register_session().
 470          */
 471         if (callback != NULL) {
 472                 int rc = callback(tpg, sess, private);
 473                 if (rc) {
 474                         transport_free_session(sess);
 475                         return ERR_PTR(rc);
 476                 }
 477         }
 478
 479         transport_register_session(tpg, sess->se_node_acl, sess, private);
 480         return sess;
 481 }
 482 EXPORT_SYMBOL(target_setup_session);
 483
 484 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
 485 {
 486         struct se_session *se_sess;
 487         ssize_t len = 0;
 488
 489         spin_lock_bh(&se_tpg->session_lock);
 490         list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
 491                 if (!se_sess->se_node_acl)
 492                         continue;
 493                 if (!se_sess->se_node_acl->dynamic_node_acl)
 494                         continue;
 495                 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
 496                         break;
 497
 498                 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
 499                                 se_sess->se_node_acl->initiatorname);
 500                 len += 1; /* Include NULL terminator */
 501         }
 502         spin_unlock_bh(&se_tpg->session_lock);
 503
 504         return len;
 505 }
 506 EXPORT_SYMBOL(target_show_dynamic_sessions);
 507
 508 static void target_complete_nacl(struct kref *kref)
 509 {
 510         struct se_node_acl *nacl = container_of(kref,
 511                                 struct se_node_acl, acl_kref);
 512         struct se_portal_group *se_tpg = nacl->se_tpg;
 513
 514         if (!nacl->dynamic_stop) {
 515                 complete(&nacl->acl_free_comp);
 516                 return;
 517         }
 518
 519         mutex_lock(&se_tpg->acl_node_mutex);
 520         list_del_init(&nacl->acl_list);
 521         mutex_unlock(&se_tpg->acl_node_mutex);
 522
 523         core_tpg_wait_for_nacl_pr_ref(nacl);
 524         core_free_device_list_for_node(nacl, se_tpg);
 525         kfree(nacl);
 526 }
 527
 528 void target_put_nacl(struct se_node_acl *nacl)
 529 {
 530         kref_put(&nacl->acl_kref, target_complete_nacl);
 531 }
 532 EXPORT_SYMBOL(target_put_nacl);
 533
 534 void transport_deregister_session_configfs(struct se_session *se_sess)
 535 {
 536         struct se_node_acl *se_nacl;
 537         unsigned long flags;
 538         /*
 539          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 540          */
 541         se_nacl = se_sess->se_node_acl;
 542         if (se_nacl) {
 543                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 544                 if (!list_empty(&se_sess->sess_acl_list))
 545                         list_del_init(&se_sess->sess_acl_list);
 546                 /*
 547                  * If the session list is empty, then clear the pointer.
 548                  * Otherwise, set the struct se_session pointer from the tail
 549                  * element of the per struct se_node_acl active session list.
 550                  */
 551                 if (list_empty(&se_nacl->acl_sess_list))
 552                         se_nacl->nacl_sess = NULL;
 553                 else {
 554                         se_nacl->nacl_sess = container_of(
 555                                         se_nacl->acl_sess_list.prev,
 556                                         struct se_session, sess_acl_list);
 557                 }
 558                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 559         }
 560 }
 561 EXPORT_SYMBOL(transport_deregister_session_configfs);
 562
 563 void transport_free_session(struct se_session *se_sess)
 564 {
 565         struct se_node_acl *se_nacl = se_sess->se_node_acl;
 566
 567         /*
 568          * Drop the se_node_acl->nacl_kref obtained from within
 569          * core_tpg_get_initiator_node_acl().
 570          */
 571         if (se_nacl) {
 572                 struct se_portal_group *se_tpg = se_nacl->se_tpg;
 573                 const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
 574                 unsigned long flags;
 575
 576                 se_sess->se_node_acl = NULL;
 577
 578                 /*
 579                  * Also determine if we need to drop the extra ->cmd_kref if
 580                  * it had been previously dynamically generated, and
 581                  * the endpoint is not caching dynamic ACLs.
 582                  */
 583                 mutex_lock(&se_tpg->acl_node_mutex);
 584                 if (se_nacl->dynamic_node_acl &&
 585                     !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 586                         spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 587                         if (list_empty(&se_nacl->acl_sess_list))
 588                                 se_nacl->dynamic_stop = true;
 589                         spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 590
 591                         if (se_nacl->dynamic_stop)
 592                                 list_del_init(&se_nacl->acl_list);
 593                 }
 594                 mutex_unlock(&se_tpg->acl_node_mutex);
 595
 596                 if (se_nacl->dynamic_stop)
 597                         target_put_nacl(se_nacl);
 598
 599                 target_put_nacl(se_nacl);
 600         }
 601         if (se_sess->sess_cmd_map) {
 602                 sbitmap_queue_free(&se_sess->sess_tag_pool);
 603                 kvfree(se_sess->sess_cmd_map);
 604         }
 605         transport_uninit_session(se_sess);
 606         kmem_cache_free(se_sess_cache, se_sess);
 607 }
 608 EXPORT_SYMBOL(transport_free_session);
 609
 610 static int target_release_res(struct se_device *dev, void *data)
 611 {
 612         struct se_session *sess = data;
 613
 614         if (dev->reservation_holder == sess)
 615                 target_release_reservation(dev);
 616         return 0;
 617 }
 618
 619 void transport_deregister_session(struct se_session *se_sess)
 620 {
 621         struct se_portal_group *se_tpg = se_sess->se_tpg;
 622         unsigned long flags;
 623
 624         if (!se_tpg) {
 625                 transport_free_session(se_sess);
 626                 return;
 627         }
 628
 629         spin_lock_irqsave(&se_tpg->session_lock, flags);
 630         list_del(&se_sess->sess_list);
 631         se_sess->se_tpg = NULL;
 632         se_sess->fabric_sess_ptr = NULL;
 633         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 634
 635         /*
 636          * Since the session is being removed, release SPC-2
 637          * reservations held by the session that is disappearing.
 638          */
 639         target_for_each_device(target_release_res, se_sess);
 640
 641         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 642                 se_tpg->se_tpg_tfo->fabric_name);
 643         /*
 644          * If last kref is dropping now for an explicit NodeACL, awake sleeping
 645          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 646          * removal context from within transport_free_session() code.
 647          *
 648          * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
 649          * to release all remaining generate_node_acl=1 created ACL resources.
 650          */
 651
 652         transport_free_session(se_sess);
 653 }
 654 EXPORT_SYMBOL(transport_deregister_session);
 655
 656 void target_remove_session(struct se_session *se_sess)
 657 {
 658         transport_deregister_session_configfs(se_sess);
 659         transport_deregister_session(se_sess);
 660 }
 661 EXPORT_SYMBOL(target_remove_session);
 662
 663 static void target_remove_from_state_list(struct se_cmd *cmd)
 664 {
 665         struct se_device *dev = cmd->se_dev;
 666         unsigned long flags;
 667
 668         if (!dev)
 669                 return;
 670
 671         spin_lock_irqsave(&dev->queues[cmd->cpuid].lock, flags);
 672         if (cmd->state_active) {
 673                 list_del(&cmd->state_list);
 674                 cmd->state_active = false;
 675         }
 676         spin_unlock_irqrestore(&dev->queues[cmd->cpuid].lock, flags);
 677 }
 678
 679 static void target_remove_from_tmr_list(struct se_cmd *cmd)
 680 {
 681         struct se_device *dev = NULL;
 682         unsigned long flags;
 683
 684         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
 685                 dev = cmd->se_tmr_req->tmr_dev;
 686
 687         if (dev) {
 688                 spin_lock_irqsave(&dev->se_tmr_lock, flags);
 689                 if (cmd->se_tmr_req->tmr_dev)
 690                         list_del_init(&cmd->se_tmr_req->tmr_list);
 691                 spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
 692         }
 693 }
 694 /*
 695  * This function is called by the target core after the target core has
 696  * finished processing a SCSI command or SCSI TMF. Both the regular command
 697  * processing code and the code for aborting commands can call this
 698  * function. CMD_T_STOP is set if and only if another thread is waiting
 699  * inside transport_wait_for_tasks() for t_transport_stop_comp.
 700  */
 701 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 702 {
 703         unsigned long flags;
 704
 705         spin_lock_irqsave(&cmd->t_state_lock, flags);
 706         /*
 707          * Determine if frontend context caller is requesting the stopping of
 708          * this command for frontend exceptions.
 709          */
 710         if (cmd->transport_state & CMD_T_STOP) {
 711                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
 712                         __func__, __LINE__, cmd->tag);
 713
 714                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 715
 716                 complete_all(&cmd->t_transport_stop_comp);
 717                 return 1;
 718         }
 719         cmd->transport_state &= ~CMD_T_ACTIVE;
 720         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 721
 722         /*
 723          * Some fabric modules like tcm_loop can release their internally
 724          * allocated I/O reference and struct se_cmd now.
 725          *
 726          * Fabric modules are expected to return '1' here if the se_cmd being
 727          * passed is released at this point, or zero if not being released.
 728          */
 729         return cmd->se_tfo->check_stop_free(cmd);
 730 }
 731
 732 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 733 {
 734         struct se_lun *lun = cmd->se_lun;
 735
 736         if (!lun)
 737                 return;
 738
 739         target_remove_from_state_list(cmd);
 740         target_remove_from_tmr_list(cmd);
 741
 742         if (cmpxchg(&cmd->lun_ref_active, true, false))
 743                 percpu_ref_put(&lun->lun_ref);
 744
 745         /*
 746          * Clear struct se_cmd->se_lun before the handoff to FE.
 747          */
 748         cmd->se_lun = NULL;
 749 }
 750
 751 static void target_complete_failure_work(struct work_struct *work)
 752 {
 753         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 754
 755         transport_generic_request_failure(cmd, cmd->sense_reason);
 756 }
 757
 758 /*
 759  * Used when asking transport to copy Sense Data from the underlying
 760  * Linux/SCSI struct scsi_cmnd
 761  */
 762 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 763 {
 764         struct se_device *dev = cmd->se_dev;
 765
 766         WARN_ON(!cmd->se_lun);
 767
 768         if (!dev)
 769                 return NULL;
 770
 771         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 772                 return NULL;
 773
 774         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 775
 776         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 777                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 778         return cmd->sense_buffer;
 779 }
 780
 781 void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
 782 {
 783         unsigned char *cmd_sense_buf;
 784         unsigned long flags;
 785
 786         spin_lock_irqsave(&cmd->t_state_lock, flags);
 787         cmd_sense_buf = transport_get_sense_buffer(cmd);
 788         if (!cmd_sense_buf) {
 789                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 790                 return;
 791         }
 792
 793         cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
 794         memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
 795         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 796 }
 797 EXPORT_SYMBOL(transport_copy_sense_to_cmd);
 798
 799 static void target_handle_abort(struct se_cmd *cmd)
 800 {
 801         bool tas = cmd->transport_state & CMD_T_TAS;
 802         bool ack_kref = cmd->se_cmd_flags & SCF_ACK_KREF;
 803         int ret;
 804
 805         pr_debug("tag %#llx: send_abort_response = %d\n", cmd->tag, tas);
 806
 807         if (tas) {
 808                 if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
 809                         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
 810                         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
 811                                  cmd->t_task_cdb[0], cmd->tag);
 812                         trace_target_cmd_complete(cmd);
 813                         ret = cmd->se_tfo->queue_status(cmd);
 814                         if (ret) {
 815                                 transport_handle_queue_full(cmd, cmd->se_dev,
 816                                                             ret, false);
 817                                 return;
 818                         }
 819                 } else {
 820                         cmd->se_tmr_req->response = TMR_FUNCTION_REJECTED;
 821                         cmd->se_tfo->queue_tm_rsp(cmd);
 822                 }
 823         } else {
 824                 /*
 825                  * Allow the fabric driver to unmap any resources before
 826                  * releasing the descriptor via TFO->release_cmd().
 827                  */
 828                 cmd->se_tfo->aborted_task(cmd);
 829                 if (ack_kref)
 830                         WARN_ON_ONCE(target_put_sess_cmd(cmd) != 0);
 831                 /*
 832                  * To do: establish a unit attention condition on the I_T
 833                  * nexus associated with cmd. See also the paragraph "Aborting
 834                  * commands" in SAM.
 835                  */
 836         }
 837
 838         WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0);
 839
 840         transport_lun_remove_cmd(cmd);
 841
 842         transport_cmd_check_stop_to_fabric(cmd);
 843 }
 844
 845 static void target_abort_work(struct work_struct *work)
 846 {
 847         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 848
 849         target_handle_abort(cmd);
 850 }
 851
 852 static bool target_cmd_interrupted(struct se_cmd *cmd)
 853 {
 854         int post_ret;
 855
 856         if (cmd->transport_state & CMD_T_ABORTED) {
 857                 if (cmd->transport_complete_callback)
 858                         cmd->transport_complete_callback(cmd, false, &post_ret);
 859                 INIT_WORK(&cmd->work, target_abort_work);
 860                 queue_work(target_completion_wq, &cmd->work);
 861                 return true;
 862         } else if (cmd->transport_state & CMD_T_STOP) {
 863                 if (cmd->transport_complete_callback)
 864                         cmd->transport_complete_callback(cmd, false, &post_ret);
 865                 complete_all(&cmd->t_transport_stop_comp);
 866                 return true;
 867         }
 868
 869         return false;
 870 }
 871
 872 /* May be called from interrupt context so must not sleep. */
 873 void target_complete_cmd_with_sense(struct se_cmd *cmd, u8 scsi_status,
 874                                     sense_reason_t sense_reason)
 875 {
 876         struct se_wwn *wwn = cmd->se_sess->se_tpg->se_tpg_wwn;
 877         int success, cpu;
 878         unsigned long flags;
 879
 880         if (target_cmd_interrupted(cmd))
 881                 return;
 882
 883         cmd->scsi_status = scsi_status;
 884         cmd->sense_reason = sense_reason;
 885
 886         spin_lock_irqsave(&cmd->t_state_lock, flags);
 887         switch (cmd->scsi_status) {
 888         case SAM_STAT_CHECK_CONDITION:
 889                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 890                         success = 1;
 891                 else
 892                         success = 0;
 893                 break;
 894         default:
 895                 success = 1;
 896                 break;
 897         }
 898
 899         cmd->t_state = TRANSPORT_COMPLETE;
 900         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 901         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 902
 903         INIT_WORK(&cmd->work, success ? target_complete_ok_work :
 904                   target_complete_failure_work);
 905
 906         if (!wwn || wwn->cmd_compl_affinity == SE_COMPL_AFFINITY_CPUID)
 907                 cpu = cmd->cpuid;
 908         else
 909                 cpu = wwn->cmd_compl_affinity;
 910
 911         queue_work_on(cpu, target_completion_wq, &cmd->work);
 912 }
 913 EXPORT_SYMBOL(target_complete_cmd_with_sense);
 914
 915 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 916 {
 917         target_complete_cmd_with_sense(cmd, scsi_status, scsi_status ?
 918                               TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE :
 919                               TCM_NO_SENSE);
 920 }
 921 EXPORT_SYMBOL(target_complete_cmd);
 922
 923 void target_set_cmd_data_length(struct se_cmd *cmd, int length)
 924 {
 925         if (length < cmd->data_length) {
 926                 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 927                         cmd->residual_count += cmd->data_length - length;
 928                 } else {
 929                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
 930                         cmd->residual_count = cmd->data_length - length;
 931                 }
 932
 933                 cmd->data_length = length;
 934         }
 935 }
 936 EXPORT_SYMBOL(target_set_cmd_data_length);
 937
 938 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 939 {
 940         if (scsi_status == SAM_STAT_GOOD ||
 941             cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) {
 942                 target_set_cmd_data_length(cmd, length);
 943         }
 944
 945         target_complete_cmd(cmd, scsi_status);
 946 }
 947 EXPORT_SYMBOL(target_complete_cmd_with_length);
 948
 949 static void target_add_to_state_list(struct se_cmd *cmd)
 950 {
 951         struct se_device *dev = cmd->se_dev;
 952         unsigned long flags;
 953
 954         spin_lock_irqsave(&dev->queues[cmd->cpuid].lock, flags);
 955         if (!cmd->state_active) {
 956                 list_add_tail(&cmd->state_list,
 957                               &dev->queues[cmd->cpuid].state_list);
 958                 cmd->state_active = true;
 959         }
 960         spin_unlock_irqrestore(&dev->queues[cmd->cpuid].lock, flags);
 961 }
 962
 963 /*
 964  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 965  */
 966 static void transport_write_pending_qf(struct se_cmd *cmd);
 967 static void transport_complete_qf(struct se_cmd *cmd);
 968
 969 void target_qf_do_work(struct work_struct *work)
 970 {
 971         struct se_device *dev = container_of(work, struct se_device,
 972                                         qf_work_queue);
 973         LIST_HEAD(qf_cmd_list);
 974         struct se_cmd *cmd, *cmd_tmp;
 975
 976         spin_lock_irq(&dev->qf_cmd_lock);
 977         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 978         spin_unlock_irq(&dev->qf_cmd_lock);
 979
 980         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 981                 list_del(&cmd->se_qf_node);
 982                 atomic_dec_mb(&dev->dev_qf_count);
 983
 984                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 985                         " context: %s\n", cmd->se_tfo->fabric_name, cmd,
 986                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 987                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 988                         : "UNKNOWN");
 989
 990                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 991                         transport_write_pending_qf(cmd);
 992                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
 993                          cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
 994                         transport_complete_qf(cmd);
 995         }
 996 }
 997
 998 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 999 {
1000         switch (cmd->data_direction) {
1001         case DMA_NONE:
1002                 return "NONE";
1003         case DMA_FROM_DEVICE:
1004                 return "READ";
1005         case DMA_TO_DEVICE:
1006                 return "WRITE";
1007         case DMA_BIDIRECTIONAL:
1008                 return "BIDI";
1009         default:
1010                 break;
1011         }
1012
1013         return "UNKNOWN";
1014 }
1015
1016 void transport_dump_dev_state(
1017         struct se_device *dev,
1018         char *b,
1019         int *bl)
1020 {
1021         *bl += sprintf(b + *bl, "Status: ");
1022         if (dev->export_count)
1023                 *bl += sprintf(b + *bl, "ACTIVATED");
1024         else
1025                 *bl += sprintf(b + *bl, "DEACTIVATED");
1026
1027         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
1028         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
1029                 dev->dev_attrib.block_size,
1030                 dev->dev_attrib.hw_max_sectors);
1031         *bl += sprintf(b + *bl, "        ");
1032 }
1033
1034 void transport_dump_vpd_proto_id(
1035         struct t10_vpd *vpd,
1036         unsigned char *p_buf,
1037         int p_buf_len)
1038 {
1039         unsigned char buf[VPD_TMP_BUF_SIZE];
1040         int len;
1041
1042         memset(buf, 0, VPD_TMP_BUF_SIZE);
1043         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
1044
1045         switch (vpd->protocol_identifier) {
1046         case 0x00:
1047                 sprintf(buf+len, "Fibre Channel\n");
1048                 break;
1049         case 0x10:
1050                 sprintf(buf+len, "Parallel SCSI\n");
1051                 break;
1052         case 0x20:
1053                 sprintf(buf+len, "SSA\n");
1054                 break;
1055         case 0x30:
1056                 sprintf(buf+len, "IEEE 1394\n");
1057                 break;
1058         case 0x40:
1059                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
1060                                 " Protocol\n");
1061                 break;
1062         case 0x50:
1063                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
1064                 break;
1065         case 0x60:
1066                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
1067                 break;
1068         case 0x70:
1069                 sprintf(buf+len, "Automation/Drive Interface Transport"
1070                                 " Protocol\n");
1071                 break;
1072         case 0x80:
1073                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
1074                 break;
1075         default:
1076                 sprintf(buf+len, "Unknown 0x%02x\n",
1077                                 vpd->protocol_identifier);
1078                 break;
1079         }
1080
1081         if (p_buf)
1082                 strncpy(p_buf, buf, p_buf_len);
1083         else
1084                 pr_debug("%s", buf);
1085 }
1086
1087 void
1088 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1089 {
1090         /*
1091          * Check if the Protocol Identifier Valid (PIV) bit is set..
1092          *
1093          * from spc3r23.pdf section 7.5.1
1094          */
1095          if (page_83[1] & 0x80) {
1096                 vpd->protocol_identifier = (page_83[0] & 0xf0);
1097                 vpd->protocol_identifier_set = 1;
1098                 transport_dump_vpd_proto_id(vpd, NULL, 0);
1099         }
1100 }
1101 EXPORT_SYMBOL(transport_set_vpd_proto_id);
1102
1103 int transport_dump_vpd_assoc(
1104         struct t10_vpd *vpd,
1105         unsigned char *p_buf,
1106         int p_buf_len)
1107 {
1108         unsigned char buf[VPD_TMP_BUF_SIZE];
1109         int ret = 0;
1110         int len;
1111
1112         memset(buf, 0, VPD_TMP_BUF_SIZE);
1113         len = sprintf(buf, "T10 VPD Identifier Association: ");
1114
1115         switch (vpd->association) {
1116         case 0x00:
1117                 sprintf(buf+len, "addressed logical unit\n");
1118                 break;
1119         case 0x10:
1120                 sprintf(buf+len, "target port\n");
1121                 break;
1122         case 0x20:
1123                 sprintf(buf+len, "SCSI target device\n");
1124                 break;
1125         default:
1126                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1127                 ret = -EINVAL;
1128                 break;
1129         }
1130
1131         if (p_buf)
1132                 strncpy(p_buf, buf, p_buf_len);
1133         else
1134                 pr_debug("%s", buf);
1135
1136         return ret;
1137 }
1138
1139 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1140 {
1141         /*
1142          * The VPD identification association..
1143          *
1144          * from spc3r23.pdf Section 7.6.3.1 Table 297
1145          */
1146         vpd->association = (page_83[1] & 0x30);
1147         return transport_dump_vpd_assoc(vpd, NULL, 0);
1148 }
1149 EXPORT_SYMBOL(transport_set_vpd_assoc);
1150
1151 int transport_dump_vpd_ident_type(
1152         struct t10_vpd *vpd,
1153         unsigned char *p_buf,
1154         int p_buf_len)
1155 {
1156         unsigned char buf[VPD_TMP_BUF_SIZE];
1157         int ret = 0;
1158         int len;
1159
1160         memset(buf, 0, VPD_TMP_BUF_SIZE);
1161         len = sprintf(buf, "T10 VPD Identifier Type: ");
1162
1163         switch (vpd->device_identifier_type) {
1164         case 0x00:
1165                 sprintf(buf+len, "Vendor specific\n");
1166                 break;
1167         case 0x01:
1168                 sprintf(buf+len, "T10 Vendor ID based\n");
1169                 break;
1170         case 0x02:
1171                 sprintf(buf+len, "EUI-64 based\n");
1172                 break;
1173         case 0x03:
1174                 sprintf(buf+len, "NAA\n");
1175                 break;
1176         case 0x04:
1177                 sprintf(buf+len, "Relative target port identifier\n");
1178                 break;
1179         case 0x08:
1180                 sprintf(buf+len, "SCSI name string\n");
1181                 break;
1182         default:
1183                 sprintf(buf+len, "Unsupported: 0x%02x\n",
1184                                 vpd->device_identifier_type);
1185                 ret = -EINVAL;
1186                 break;
1187         }
1188
1189         if (p_buf) {
1190                 if (p_buf_len < strlen(buf)+1)
1191                         return -EINVAL;
1192                 strncpy(p_buf, buf, p_buf_len);
1193         } else {
1194                 pr_debug("%s", buf);
1195         }
1196
1197         return ret;
1198 }
1199
1200 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1201 {
1202         /*
1203          * The VPD identifier type..
1204          *
1205          * from spc3r23.pdf Section 7.6.3.1 Table 298
1206          */
1207         vpd->device_identifier_type = (page_83[1] & 0x0f);
1208         return transport_dump_vpd_ident_type(vpd, NULL, 0);
1209 }
1210 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1211
1212 int transport_dump_vpd_ident(
1213         struct t10_vpd *vpd,
1214         unsigned char *p_buf,
1215         int p_buf_len)
1216 {
1217         unsigned char buf[VPD_TMP_BUF_SIZE];
1218         int ret = 0;
1219
1220         memset(buf, 0, VPD_TMP_BUF_SIZE);
1221
1222         switch (vpd->device_identifier_code_set) {
1223         case 0x01: /* Binary */
1224                 snprintf(buf, sizeof(buf),
1225                         "T10 VPD Binary Device Identifier: %s\n",
1226                         &vpd->device_identifier[0]);
1227                 break;
1228         case 0x02: /* ASCII */
1229                 snprintf(buf, sizeof(buf),
1230                         "T10 VPD ASCII Device Identifier: %s\n",
1231                         &vpd->device_identifier[0]);
1232                 break;
1233         case 0x03: /* UTF-8 */
1234                 snprintf(buf, sizeof(buf),
1235                         "T10 VPD UTF-8 Device Identifier: %s\n",
1236                         &vpd->device_identifier[0]);
1237                 break;
1238         default:
1239                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1240                         " 0x%02x", vpd->device_identifier_code_set);
1241                 ret = -EINVAL;
1242                 break;
1243         }
1244
1245         if (p_buf)
1246                 strncpy(p_buf, buf, p_buf_len);
1247         else
1248                 pr_debug("%s", buf);
1249
1250         return ret;
1251 }
1252
1253 int
1254 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1255 {
1256         static const char hex_str[] = "0123456789abcdef";
1257         int j = 0, i = 4; /* offset to start of the identifier */
1258
1259         /*
1260          * The VPD Code Set (encoding)
1261          *
1262          * from spc3r23.pdf Section 7.6.3.1 Table 296
1263          */
1264         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1265         switch (vpd->device_identifier_code_set) {
1266         case 0x01: /* Binary */
1267                 vpd->device_identifier[j++] =
1268                                 hex_str[vpd->device_identifier_type];
1269                 while (i < (4 + page_83[3])) {
1270                         vpd->device_identifier[j++] =
1271                                 hex_str[(page_83[i] & 0xf0) >> 4];
1272                         vpd->device_identifier[j++] =
1273                                 hex_str[page_83[i] & 0x0f];
1274                         i++;
1275                 }
1276                 break;
1277         case 0x02: /* ASCII */
1278         case 0x03: /* UTF-8 */
1279                 while (i < (4 + page_83[3]))
1280                         vpd->device_identifier[j++] = page_83[i++];
1281                 break;
1282         default:
1283                 break;
1284         }
1285
1286         return transport_dump_vpd_ident(vpd, NULL, 0);
1287 }
1288 EXPORT_SYMBOL(transport_set_vpd_ident);
1289
1290 static sense_reason_t
1291 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1292                                unsigned int size)
1293 {
1294         u32 mtl;
1295
1296         if (!cmd->se_tfo->max_data_sg_nents)
1297                 return TCM_NO_SENSE;
1298         /*
1299          * Check if fabric enforced maximum SGL entries per I/O descriptor
1300          * exceeds se_cmd->data_length.  If true, set SCF_UNDERFLOW_BIT +
1301          * residual_count and reduce original cmd->data_length to maximum
1302          * length based on single PAGE_SIZE entry scatter-lists.
1303          */
1304         mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1305         if (cmd->data_length > mtl) {
1306                 /*
1307                  * If an existing CDB overflow is present, calculate new residual
1308                  * based on CDB size minus fabric maximum transfer length.
1309                  *
1310                  * If an existing CDB underflow is present, calculate new residual
1311                  * based on original cmd->data_length minus fabric maximum transfer
1312                  * length.
1313                  *
1314                  * Otherwise, set the underflow residual based on cmd->data_length
1315                  * minus fabric maximum transfer length.
1316                  */
1317                 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1318                         cmd->residual_count = (size - mtl);
1319                 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1320                         u32 orig_dl = size + cmd->residual_count;
1321                         cmd->residual_count = (orig_dl - mtl);
1322                 } else {
1323                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1324                         cmd->residual_count = (cmd->data_length - mtl);
1325                 }
1326                 cmd->data_length = mtl;
1327                 /*
1328                  * Reset sbc_check_prot() calculated protection payload
1329                  * length based upon the new smaller MTL.
1330                  */
1331                 if (cmd->prot_length) {
1332                         u32 sectors = (mtl / dev->dev_attrib.block_size);
1333                         cmd->prot_length = dev->prot_length * sectors;
1334                 }
1335         }
1336         return TCM_NO_SENSE;
1337 }
1338
1339 /**
1340  * target_cmd_size_check - Check whether there will be a residual.
1341  * @cmd: SCSI command.
1342  * @size: Data buffer size derived from CDB. The data buffer size provided by
1343  *   the SCSI transport driver is available in @cmd->data_length.
1344  *
1345  * Compare the data buffer size from the CDB with the data buffer limit from the transport
1346  * header. Set @cmd->residual_count and SCF_OVERFLOW_BIT or SCF_UNDERFLOW_BIT if necessary.
1347  *
1348  * Note: target drivers set @cmd->data_length by calling __target_init_cmd().
1349  *
1350  * Return: TCM_NO_SENSE
1351  */
1352 sense_reason_t
1353 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1354 {
1355         struct se_device *dev = cmd->se_dev;
1356
1357         if (cmd->unknown_data_length) {
1358                 cmd->data_length = size;
1359         } else if (size != cmd->data_length) {
1360                 pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1361                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1362                         " 0x%02x\n", cmd->se_tfo->fabric_name,
1363                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1364                 /*
1365                  * For READ command for the overflow case keep the existing
1366                  * fabric provided ->data_length. Otherwise for the underflow
1367                  * case, reset ->data_length to the smaller SCSI expected data
1368                  * transfer length.
1369                  */
1370                 if (size > cmd->data_length) {
1371                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1372                         cmd->residual_count = (size - cmd->data_length);
1373                 } else {
1374                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1375                         cmd->residual_count = (cmd->data_length - size);
1376                         /*
1377                          * Do not truncate ->data_length for WRITE command to
1378                          * dump all payload
1379                          */
1380                         if (cmd->data_direction == DMA_FROM_DEVICE) {
1381                                 cmd->data_length = size;
1382                         }
1383                 }
1384
1385                 if (cmd->data_direction == DMA_TO_DEVICE) {
1386                         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1387                                 pr_err_ratelimited("Rejecting underflow/overflow"
1388                                                    " for WRITE data CDB\n");
1389                                 return TCM_INVALID_FIELD_IN_COMMAND_IU;
1390                         }
1391                         /*
1392                          * Some fabric drivers like iscsi-target still expect to
1393                          * always reject overflow writes.  Reject this case until
1394                          * full fabric driver level support for overflow writes
1395                          * is introduced tree-wide.
1396                          */
1397                         if (size > cmd->data_length) {
1398                                 pr_err_ratelimited("Rejecting overflow for"
1399                                                    " WRITE control CDB\n");
1400                                 return TCM_INVALID_CDB_FIELD;
1401                         }
1402                 }
1403         }
1404
1405         return target_check_max_data_sg_nents(cmd, dev, size);
1406
1407 }
1408
1409 /*
1410  * Used by fabric modules containing a local struct se_cmd within their
1411  * fabric dependent per I/O descriptor.
1412  *
1413  * Preserves the value of @cmd->tag.
1414  */
1415 void __target_init_cmd(
1416         struct se_cmd *cmd,
1417         const struct target_core_fabric_ops *tfo,
1418         struct se_session *se_sess,
1419         u32 data_length,
1420         int data_direction,
1421         int task_attr,
1422         unsigned char *sense_buffer, u64 unpacked_lun)
1423 {
1424         INIT_LIST_HEAD(&cmd->se_delayed_node);
1425         INIT_LIST_HEAD(&cmd->se_qf_node);
1426         INIT_LIST_HEAD(&cmd->state_list);
1427         init_completion(&cmd->t_transport_stop_comp);
1428         cmd->free_compl = NULL;
1429         cmd->abrt_compl = NULL;
1430         spin_lock_init(&cmd->t_state_lock);
1431         INIT_WORK(&cmd->work, NULL);
1432         kref_init(&cmd->cmd_kref);
1433
1434         cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1435         cmd->se_tfo = tfo;
1436         cmd->se_sess = se_sess;
1437         cmd->data_length = data_length;
1438         cmd->data_direction = data_direction;
1439         cmd->sam_task_attr = task_attr;
1440         cmd->sense_buffer = sense_buffer;
1441         cmd->orig_fe_lun = unpacked_lun;
1442
1443         if (!(cmd->se_cmd_flags & SCF_USE_CPUID))
1444                 cmd->cpuid = raw_smp_processor_id();
1445
1446         cmd->state_active = false;
1447 }
1448 EXPORT_SYMBOL(__target_init_cmd);
1449
1450 static sense_reason_t
1451 transport_check_alloc_task_attr(struct se_cmd *cmd)
1452 {
1453         struct se_device *dev = cmd->se_dev;
1454
1455         /*
1456          * Check if SAM Task Attribute emulation is enabled for this
1457          * struct se_device storage object
1458          */
1459         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1460                 return 0;
1461
1462         if (cmd->sam_task_attr == TCM_ACA_TAG) {
1463                 pr_debug("SAM Task Attribute ACA"
1464                         " emulation is not supported\n");
1465                 return TCM_INVALID_CDB_FIELD;
1466         }
1467
1468         return 0;
1469 }
1470
1471 sense_reason_t
1472 target_cmd_init_cdb(struct se_cmd *cmd, unsigned char *cdb, gfp_t gfp)
1473 {
1474         sense_reason_t ret;
1475
1476         /*
1477          * Ensure that the received CDB is less than the max (252 + 8) bytes
1478          * for VARIABLE_LENGTH_CMD
1479          */
1480         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1481                 pr_err("Received SCSI CDB with command_size: %d that"
1482                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1483                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1484                 ret = TCM_INVALID_CDB_FIELD;
1485                 goto err;
1486         }
1487         /*
1488          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1489          * allocate the additional extended CDB buffer now..  Otherwise
1490          * setup the pointer from __t_task_cdb to t_task_cdb.
1491          */
1492         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1493                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb), gfp);
1494                 if (!cmd->t_task_cdb) {
1495                         pr_err("Unable to allocate cmd->t_task_cdb"
1496                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1497                                 scsi_command_size(cdb),
1498                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1499                         ret = TCM_OUT_OF_RESOURCES;
1500                         goto err;
1501                 }
1502         }
1503         /*
1504          * Copy the original CDB into cmd->
1505          */
1506         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1507
1508         trace_target_sequencer_start(cmd);
1509         return 0;
1510
1511 err:
1512         /*
1513          * Copy the CDB here to allow trace_target_cmd_complete() to
1514          * print the cdb to the trace buffers.
1515          */
1516         memcpy(cmd->t_task_cdb, cdb, min(scsi_command_size(cdb),
1517                                          (unsigned int)TCM_MAX_COMMAND_SIZE));
1518         return ret;
1519 }
1520 EXPORT_SYMBOL(target_cmd_init_cdb);
1521
1522 sense_reason_t
1523 target_cmd_parse_cdb(struct se_cmd *cmd)
1524 {
1525         struct se_device *dev = cmd->se_dev;
1526         sense_reason_t ret;
1527
1528         ret = dev->transport->parse_cdb(cmd);
1529         if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1530                 pr_debug_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1531                                      cmd->se_tfo->fabric_name,
1532                                      cmd->se_sess->se_node_acl->initiatorname,
1533                                      cmd->t_task_cdb[0]);
1534         if (ret)
1535                 return ret;
1536
1537         ret = transport_check_alloc_task_attr(cmd);
1538         if (ret)
1539                 return ret;
1540
1541         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1542         atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1543         return 0;
1544 }
1545 EXPORT_SYMBOL(target_cmd_parse_cdb);
1546
1547 /*
1548  * Used by fabric module frontends to queue tasks directly.
1549  * May only be used from process context.
1550  */
1551 int transport_handle_cdb_direct(
1552         struct se_cmd *cmd)
1553 {
1554         sense_reason_t ret;
1555
1556         might_sleep();
1557
1558         if (!cmd->se_lun) {
1559                 dump_stack();
1560                 pr_err("cmd->se_lun is NULL\n");
1561                 return -EINVAL;
1562         }
1563
1564         /*
1565          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1566          * outstanding descriptors are handled correctly during shutdown via
1567          * transport_wait_for_tasks()
1568          *
1569          * Also, we don't take cmd->t_state_lock here as we only expect
1570          * this to be called for initial descriptor submission.
1571          */
1572         cmd->t_state = TRANSPORT_NEW_CMD;
1573         cmd->transport_state |= CMD_T_ACTIVE;
1574
1575         /*
1576          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1577          * so follow TRANSPORT_NEW_CMD processing thread context usage
1578          * and call transport_generic_request_failure() if necessary..
1579          */
1580         ret = transport_generic_new_cmd(cmd);
1581         if (ret)
1582                 transport_generic_request_failure(cmd, ret);
1583         return 0;
1584 }
1585 EXPORT_SYMBOL(transport_handle_cdb_direct);
1586
1587 sense_reason_t
1588 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1589                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1590 {
1591         if (!sgl || !sgl_count)
1592                 return 0;
1593
1594         /*
1595          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1596          * scatterlists already have been set to follow what the fabric
1597          * passes for the original expected data transfer length.
1598          */
1599         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1600                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1601                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1602                 return TCM_INVALID_CDB_FIELD;
1603         }
1604
1605         cmd->t_data_sg = sgl;
1606         cmd->t_data_nents = sgl_count;
1607         cmd->t_bidi_data_sg = sgl_bidi;
1608         cmd->t_bidi_data_nents = sgl_bidi_count;
1609
1610         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1611         return 0;
1612 }
1613
1614 /**
1615  * target_init_cmd - initialize se_cmd
1616  * @se_cmd: command descriptor to init
1617  * @se_sess: associated se_sess for endpoint
1618  * @sense: pointer to SCSI sense buffer
1619  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1620  * @data_length: fabric expected data transfer length
1621  * @task_attr: SAM task attribute
1622  * @data_dir: DMA data direction
1623  * @flags: flags for command submission from target_sc_flags_tables
1624  *
1625  * Task tags are supported if the caller has set @se_cmd->tag.
1626  *
1627  * Returns:
1628  *      - less than zero to signal active I/O shutdown failure.
1629  *      - zero on success.
1630  *
1631  * If the fabric driver calls target_stop_session, then it must check the
1632  * return code and handle failures. This will never fail for other drivers,
1633  * and the return code can be ignored.
1634  */
1635 int target_init_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1636                     unsigned char *sense, u64 unpacked_lun,
1637                     u32 data_length, int task_attr, int data_dir, int flags)
1638 {
1639         struct se_portal_group *se_tpg;
1640
1641         se_tpg = se_sess->se_tpg;
1642         BUG_ON(!se_tpg);
1643         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1644
1645         if (flags & TARGET_SCF_USE_CPUID)
1646                 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1647         /*
1648          * Signal bidirectional data payloads to target-core
1649          */
1650         if (flags & TARGET_SCF_BIDI_OP)
1651                 se_cmd->se_cmd_flags |= SCF_BIDI;
1652
1653         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1654                 se_cmd->unknown_data_length = 1;
1655         /*
1656          * Initialize se_cmd for target operation.  From this point
1657          * exceptions are handled by sending exception status via
1658          * target_core_fabric_ops->queue_status() callback
1659          */
1660         __target_init_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, data_length,
1661                           data_dir, task_attr, sense, unpacked_lun);
1662
1663         /*
1664          * Obtain struct se_cmd->cmd_kref reference. A second kref_get here is
1665          * necessary for fabrics using TARGET_SCF_ACK_KREF that expect a second
1666          * kref_put() to happen during fabric packet acknowledgement.
1667          */
1668         return target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1669 }
1670 EXPORT_SYMBOL_GPL(target_init_cmd);
1671
1672 /**
1673  * target_submit_prep - prepare cmd for submission
1674  * @se_cmd: command descriptor to prep
1675  * @cdb: pointer to SCSI CDB
1676  * @sgl: struct scatterlist memory for unidirectional mapping
1677  * @sgl_count: scatterlist count for unidirectional mapping
1678  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1679  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1680  * @sgl_prot: struct scatterlist memory protection information
1681  * @sgl_prot_count: scatterlist count for protection information
1682  * @gfp: gfp allocation type
1683  *
1684  * Returns:
1685  *      - less than zero to signal failure.
1686  *      - zero on success.
1687  *
1688  * If failure is returned, lio will the callers queue_status to complete
1689  * the cmd.
1690  */
1691 int target_submit_prep(struct se_cmd *se_cmd, unsigned char *cdb,
1692                        struct scatterlist *sgl, u32 sgl_count,
1693                        struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1694                        struct scatterlist *sgl_prot, u32 sgl_prot_count,
1695                        gfp_t gfp)
1696 {
1697         sense_reason_t rc;
1698
1699         rc = target_cmd_init_cdb(se_cmd, cdb, gfp);
1700         if (rc)
1701                 goto send_cc_direct;
1702
1703         /*
1704          * Locate se_lun pointer and attach it to struct se_cmd
1705          */
1706         rc = transport_lookup_cmd_lun(se_cmd);
1707         if (rc)
1708                 goto send_cc_direct;
1709
1710         rc = target_cmd_parse_cdb(se_cmd);
1711         if (rc != 0)
1712                 goto generic_fail;
1713
1714         /*
1715          * Save pointers for SGLs containing protection information,
1716          * if present.
1717          */
1718         if (sgl_prot_count) {
1719                 se_cmd->t_prot_sg = sgl_prot;
1720                 se_cmd->t_prot_nents = sgl_prot_count;
1721                 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1722         }
1723
1724         /*
1725          * When a non zero sgl_count has been passed perform SGL passthrough
1726          * mapping for pre-allocated fabric memory instead of having target
1727          * core perform an internal SGL allocation..
1728          */
1729         if (sgl_count != 0) {
1730                 BUG_ON(!sgl);
1731
1732                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1733                                 sgl_bidi, sgl_bidi_count);
1734                 if (rc != 0)
1735                         goto generic_fail;
1736         }
1737
1738         return 0;
1739
1740 send_cc_direct:
1741         transport_send_check_condition_and_sense(se_cmd, rc, 0);
1742         target_put_sess_cmd(se_cmd);
1743         return -EIO;
1744
1745 generic_fail:
1746         transport_generic_request_failure(se_cmd, rc);
1747         return -EIO;
1748 }
1749 EXPORT_SYMBOL_GPL(target_submit_prep);
1750
1751 /**
1752  * target_submit - perform final initialization and submit cmd to LIO core
1753  * @se_cmd: command descriptor to submit
1754  *
1755  * target_submit_prep must have been called on the cmd, and this must be
1756  * called from process context.
1757  */
1758 void target_submit(struct se_cmd *se_cmd)
1759 {
1760         struct scatterlist *sgl = se_cmd->t_data_sg;
1761         unsigned char *buf = NULL;
1762
1763         might_sleep();
1764
1765         if (se_cmd->t_data_nents != 0) {
1766                 BUG_ON(!sgl);
1767                 /*
1768                  * A work-around for tcm_loop as some userspace code via
1769                  * scsi-generic do not memset their associated read buffers,
1770                  * so go ahead and do that here for type non-data CDBs.  Also
1771                  * note that this is currently guaranteed to be a single SGL
1772                  * for this case by target core in target_setup_cmd_from_cdb()
1773                  * -> transport_generic_cmd_sequencer().
1774                  */
1775                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1776                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1777                         if (sgl)
1778                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1779
1780                         if (buf) {
1781                                 memset(buf, 0, sgl->length);
1782                                 kunmap(sg_page(sgl));
1783                         }
1784                 }
1785
1786         }
1787
1788         /*
1789          * Check if we need to delay processing because of ALUA
1790          * Active/NonOptimized primary access state..
1791          */
1792         core_alua_check_nonop_delay(se_cmd);
1793
1794         transport_handle_cdb_direct(se_cmd);
1795 }
1796 EXPORT_SYMBOL_GPL(target_submit);
1797
1798 /**
1799  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1800  *
1801  * @se_cmd: command descriptor to submit
1802  * @se_sess: associated se_sess for endpoint
1803  * @cdb: pointer to SCSI CDB
1804  * @sense: pointer to SCSI sense buffer
1805  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1806  * @data_length: fabric expected data transfer length
1807  * @task_attr: SAM task attribute
1808  * @data_dir: DMA data direction
1809  * @flags: flags for command submission from target_sc_flags_tables
1810  *
1811  * Task tags are supported if the caller has set @se_cmd->tag.
1812  *
1813  * This may only be called from process context, and also currently
1814  * assumes internal allocation of fabric payload buffer by target-core.
1815  *
1816  * It also assumes interal target core SGL memory allocation.
1817  *
1818  * This function must only be used by drivers that do their own
1819  * sync during shutdown and does not use target_stop_session. If there
1820  * is a failure this function will call into the fabric driver's
1821  * queue_status with a CHECK_CONDITION.
1822  */
1823 void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1824                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1825                 u32 data_length, int task_attr, int data_dir, int flags)
1826 {
1827         int rc;
1828
1829         rc = target_init_cmd(se_cmd, se_sess, sense, unpacked_lun, data_length,
1830                              task_attr, data_dir, flags);
1831         WARN(rc, "Invalid target_submit_cmd use. Driver must not use target_stop_session or call target_init_cmd directly.\n");
1832         if (rc)
1833                 return;
1834
1835         if (target_submit_prep(se_cmd, cdb, NULL, 0, NULL, 0, NULL, 0,
1836                                GFP_KERNEL))
1837                 return;
1838
1839         target_submit(se_cmd);
1840 }
1841 EXPORT_SYMBOL(target_submit_cmd);
1842
1843
1844 static struct se_dev_plug *target_plug_device(struct se_device *se_dev)
1845 {
1846         struct se_dev_plug *se_plug;
1847
1848         if (!se_dev->transport->plug_device)
1849                 return NULL;
1850
1851         se_plug = se_dev->transport->plug_device(se_dev);
1852         if (!se_plug)
1853                 return NULL;
1854
1855         se_plug->se_dev = se_dev;
1856         /*
1857          * We have a ref to the lun at this point, but the cmds could
1858          * complete before we unplug, so grab a ref to the se_device so we
1859          * can call back into the backend.
1860          */
1861         config_group_get(&se_dev->dev_group);
1862         return se_plug;
1863 }
1864
1865 static void target_unplug_device(struct se_dev_plug *se_plug)
1866 {
1867         struct se_device *se_dev = se_plug->se_dev;
1868
1869         se_dev->transport->unplug_device(se_plug);
1870         config_group_put(&se_dev->dev_group);
1871 }
1872
1873 void target_queued_submit_work(struct work_struct *work)
1874 {
1875         struct se_cmd_queue *sq = container_of(work, struct se_cmd_queue, work);
1876         struct se_cmd *se_cmd, *next_cmd;
1877         struct se_dev_plug *se_plug = NULL;
1878         struct se_device *se_dev = NULL;
1879         struct llist_node *cmd_list;
1880
1881         cmd_list = llist_del_all(&sq->cmd_list);
1882         if (!cmd_list)
1883                 /* Previous call took what we were queued to submit */
1884                 return;
1885
1886         cmd_list = llist_reverse_order(cmd_list);
1887         llist_for_each_entry_safe(se_cmd, next_cmd, cmd_list, se_cmd_list) {
1888                 if (!se_dev) {
1889                         se_dev = se_cmd->se_dev;
1890                         se_plug = target_plug_device(se_dev);
1891                 }
1892
1893                 target_submit(se_cmd);
1894         }
1895
1896         if (se_plug)
1897                 target_unplug_device(se_plug);
1898 }
1899
1900 /**
1901  * target_queue_submission - queue the cmd to run on the LIO workqueue
1902  * @se_cmd: command descriptor to submit
1903  */
1904 void target_queue_submission(struct se_cmd *se_cmd)
1905 {
1906         struct se_device *se_dev = se_cmd->se_dev;
1907         int cpu = se_cmd->cpuid;
1908         struct se_cmd_queue *sq;
1909
1910         sq = &se_dev->queues[cpu].sq;
1911         llist_add(&se_cmd->se_cmd_list, &sq->cmd_list);
1912         queue_work_on(cpu, target_submission_wq, &sq->work);
1913 }
1914 EXPORT_SYMBOL_GPL(target_queue_submission);
1915
1916 static void target_complete_tmr_failure(struct work_struct *work)
1917 {
1918         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1919
1920         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1921         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1922
1923         transport_lun_remove_cmd(se_cmd);
1924         transport_cmd_check_stop_to_fabric(se_cmd);
1925 }
1926
1927 /**
1928  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1929  *                     for TMR CDBs
1930  *
1931  * @se_cmd: command descriptor to submit
1932  * @se_sess: associated se_sess for endpoint
1933  * @sense: pointer to SCSI sense buffer
1934  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1935  * @fabric_tmr_ptr: fabric context for TMR req
1936  * @tm_type: Type of TM request
1937  * @gfp: gfp type for caller
1938  * @tag: referenced task tag for TMR_ABORT_TASK
1939  * @flags: submit cmd flags
1940  *
1941  * Callable from all contexts.
1942  **/
1943
1944 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1945                 unsigned char *sense, u64 unpacked_lun,
1946                 void *fabric_tmr_ptr, unsigned char tm_type,
1947                 gfp_t gfp, u64 tag, int flags)
1948 {
1949         struct se_portal_group *se_tpg;
1950         int ret;
1951
1952         se_tpg = se_sess->se_tpg;
1953         BUG_ON(!se_tpg);
1954
1955         __target_init_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1956                           0, DMA_NONE, TCM_SIMPLE_TAG, sense, unpacked_lun);
1957         /*
1958          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1959          * allocation failure.
1960          */
1961         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1962         if (ret < 0)
1963                 return -ENOMEM;
1964
1965         if (tm_type == TMR_ABORT_TASK)
1966                 se_cmd->se_tmr_req->ref_task_tag = tag;
1967
1968         /* See target_submit_cmd for commentary */
1969         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1970         if (ret) {
1971                 core_tmr_release_req(se_cmd->se_tmr_req);
1972                 return ret;
1973         }
1974
1975         ret = transport_lookup_tmr_lun(se_cmd);
1976         if (ret)
1977                 goto failure;
1978
1979         transport_generic_handle_tmr(se_cmd);
1980         return 0;
1981
1982         /*
1983          * For callback during failure handling, push this work off
1984          * to process context with TMR_LUN_DOES_NOT_EXIST status.
1985          */
1986 failure:
1987         INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1988         schedule_work(&se_cmd->work);
1989         return 0;
1990 }
1991 EXPORT_SYMBOL(target_submit_tmr);
1992
1993 /*
1994  * Handle SAM-esque emulation for generic transport request failures.
1995  */
1996 void transport_generic_request_failure(struct se_cmd *cmd,
1997                 sense_reason_t sense_reason)
1998 {
1999         int ret = 0, post_ret;
2000
2001         pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
2002                  sense_reason);
2003         target_show_cmd("-----[ ", cmd);
2004
2005         /*
2006          * For SAM Task Attribute emulation for failed struct se_cmd
2007          */
2008         transport_complete_task_attr(cmd);
2009
2010         if (cmd->transport_complete_callback)
2011                 cmd->transport_complete_callback(cmd, false, &post_ret);
2012
2013         if (cmd->transport_state & CMD_T_ABORTED) {
2014                 INIT_WORK(&cmd->work, target_abort_work);
2015                 queue_work(target_completion_wq, &cmd->work);
2016                 return;
2017         }
2018
2019         switch (sense_reason) {
2020         case TCM_NON_EXISTENT_LUN:
2021         case TCM_UNSUPPORTED_SCSI_OPCODE:
2022         case TCM_INVALID_CDB_FIELD:
2023         case TCM_INVALID_PARAMETER_LIST:
2024         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2025         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2026         case TCM_UNKNOWN_MODE_PAGE:
2027         case TCM_WRITE_PROTECTED:
2028         case TCM_ADDRESS_OUT_OF_RANGE:
2029         case TCM_CHECK_CONDITION_ABORT_CMD:
2030         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2031         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
2032         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
2033         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
2034         case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
2035         case TCM_TOO_MANY_TARGET_DESCS:
2036         case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
2037         case TCM_TOO_MANY_SEGMENT_DESCS:
2038         case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
2039         case TCM_INVALID_FIELD_IN_COMMAND_IU:
2040         case TCM_ALUA_TG_PT_STANDBY:
2041         case TCM_ALUA_TG_PT_UNAVAILABLE:
2042         case TCM_ALUA_STATE_TRANSITION:
2043         case TCM_ALUA_OFFLINE:
2044                 break;
2045         case TCM_OUT_OF_RESOURCES:
2046                 cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
2047                 goto queue_status;
2048         case TCM_LUN_BUSY:
2049                 cmd->scsi_status = SAM_STAT_BUSY;
2050                 goto queue_status;
2051         case TCM_RESERVATION_CONFLICT:
2052                 /*
2053                  * No SENSE Data payload for this case, set SCSI Status
2054                  * and queue the response to $FABRIC_MOD.
2055                  *
2056                  * Uses linux/include/scsi/scsi.h SAM status codes defs
2057                  */
2058                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
2059                 /*
2060                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
2061                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
2062                  * CONFLICT STATUS.
2063                  *
2064                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
2065                  */
2066                 if (cmd->se_sess &&
2067                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl
2068                                         == TARGET_UA_INTLCK_CTRL_ESTABLISH_UA) {
2069                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
2070                                                cmd->orig_fe_lun, 0x2C,
2071                                         ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
2072                 }
2073
2074                 goto queue_status;
2075         default:
2076                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
2077                         cmd->t_task_cdb[0], sense_reason);
2078                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
2079                 break;
2080         }
2081
2082         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
2083         if (ret)
2084                 goto queue_full;
2085
2086 check_stop:
2087         transport_lun_remove_cmd(cmd);
2088         transport_cmd_check_stop_to_fabric(cmd);
2089         return;
2090
2091 queue_status:
2092         trace_target_cmd_complete(cmd);
2093         ret = cmd->se_tfo->queue_status(cmd);
2094         if (!ret)
2095                 goto check_stop;
2096 queue_full:
2097         transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2098 }
2099 EXPORT_SYMBOL(transport_generic_request_failure);
2100
2101 void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
2102 {
2103         sense_reason_t ret;
2104
2105         if (!cmd->execute_cmd) {
2106                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2107                 goto err;
2108         }
2109         if (do_checks) {
2110                 /*
2111                  * Check for an existing UNIT ATTENTION condition after
2112                  * target_handle_task_attr() has done SAM task attr
2113                  * checking, and possibly have already defered execution
2114                  * out to target_restart_delayed_cmds() context.
2115                  */
2116                 ret = target_scsi3_ua_check(cmd);
2117                 if (ret)
2118                         goto err;
2119
2120                 ret = target_alua_state_check(cmd);
2121                 if (ret)
2122                         goto err;
2123
2124                 ret = target_check_reservation(cmd);
2125                 if (ret) {
2126                         cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
2127                         goto err;
2128                 }
2129         }
2130
2131         ret = cmd->execute_cmd(cmd);
2132         if (!ret)
2133                 return;
2134 err:
2135         spin_lock_irq(&cmd->t_state_lock);
2136         cmd->transport_state &= ~CMD_T_SENT;
2137         spin_unlock_irq(&cmd->t_state_lock);
2138
2139         transport_generic_request_failure(cmd, ret);
2140 }
2141
2142 static int target_write_prot_action(struct se_cmd *cmd)
2143 {
2144         u32 sectors;
2145         /*
2146          * Perform WRITE_INSERT of PI using software emulation when backend
2147          * device has PI enabled, if the transport has not already generated
2148          * PI using hardware WRITE_INSERT offload.
2149          */
2150         switch (cmd->prot_op) {
2151         case TARGET_PROT_DOUT_INSERT:
2152                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
2153                         sbc_dif_generate(cmd);
2154                 break;
2155         case TARGET_PROT_DOUT_STRIP:
2156                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
2157                         break;
2158
2159                 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
2160                 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2161                                              sectors, 0, cmd->t_prot_sg, 0);
2162                 if (unlikely(cmd->pi_err)) {
2163                         spin_lock_irq(&cmd->t_state_lock);
2164                         cmd->transport_state &= ~CMD_T_SENT;
2165                         spin_unlock_irq(&cmd->t_state_lock);
2166                         transport_generic_request_failure(cmd, cmd->pi_err);
2167                         return -1;
2168                 }
2169                 break;
2170         default:
2171                 break;
2172         }
2173
2174         return 0;
2175 }
2176
2177 static bool target_handle_task_attr(struct se_cmd *cmd)
2178 {
2179         struct se_device *dev = cmd->se_dev;
2180
2181         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2182                 return false;
2183
2184         cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
2185
2186         /*
2187          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
2188          * to allow the passed struct se_cmd list of tasks to the front of the list.
2189          */
2190         switch (cmd->sam_task_attr) {
2191         case TCM_HEAD_TAG:
2192                 atomic_inc_mb(&dev->non_ordered);
2193                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
2194                          cmd->t_task_cdb[0]);
2195                 return false;
2196         case TCM_ORDERED_TAG:
2197                 atomic_inc_mb(&dev->delayed_cmd_count);
2198
2199                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
2200                          cmd->t_task_cdb[0]);
2201                 break;
2202         default:
2203                 /*
2204                  * For SIMPLE and UNTAGGED Task Attribute commands
2205                  */
2206                 atomic_inc_mb(&dev->non_ordered);
2207
2208                 if (atomic_read(&dev->delayed_cmd_count) == 0)
2209                         return false;
2210                 break;
2211         }
2212
2213         if (cmd->sam_task_attr != TCM_ORDERED_TAG) {
2214                 atomic_inc_mb(&dev->delayed_cmd_count);
2215                 /*
2216                  * We will account for this when we dequeue from the delayed
2217                  * list.
2218                  */
2219                 atomic_dec_mb(&dev->non_ordered);
2220         }
2221
2222         spin_lock_irq(&cmd->t_state_lock);
2223         cmd->transport_state &= ~CMD_T_SENT;
2224         spin_unlock_irq(&cmd->t_state_lock);
2225
2226         spin_lock(&dev->delayed_cmd_lock);
2227         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
2228         spin_unlock(&dev->delayed_cmd_lock);
2229
2230         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
2231                 cmd->t_task_cdb[0], cmd->sam_task_attr);
2232         /*
2233          * We may have no non ordered cmds when this function started or we
2234          * could have raced with the last simple/head cmd completing, so kick
2235          * the delayed handler here.
2236          */
2237         schedule_work(&dev->delayed_cmd_work);
2238         return true;
2239 }
2240
2241 void target_execute_cmd(struct se_cmd *cmd)
2242 {
2243         /*
2244          * Determine if frontend context caller is requesting the stopping of
2245          * this command for frontend exceptions.
2246          *
2247          * If the received CDB has already been aborted stop processing it here.
2248          */
2249         if (target_cmd_interrupted(cmd))
2250                 return;
2251
2252         spin_lock_irq(&cmd->t_state_lock);
2253         cmd->t_state = TRANSPORT_PROCESSING;
2254         cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
2255         spin_unlock_irq(&cmd->t_state_lock);
2256
2257         if (target_write_prot_action(cmd))
2258                 return;
2259
2260         if (target_handle_task_attr(cmd))
2261                 return;
2262
2263         __target_execute_cmd(cmd, true);
2264 }
2265 EXPORT_SYMBOL(target_execute_cmd);
2266
2267 /*
2268  * Process all commands up to the last received ORDERED task attribute which
2269  * requires another blocking boundary
2270  */
2271 void target_do_delayed_work(struct work_struct *work)
2272 {
2273         struct se_device *dev = container_of(work, struct se_device,
2274                                              delayed_cmd_work);
2275
2276         spin_lock(&dev->delayed_cmd_lock);
2277         while (!dev->ordered_sync_in_progress) {
2278                 struct se_cmd *cmd;
2279
2280                 if (list_empty(&dev->delayed_cmd_list))
2281                         break;
2282
2283                 cmd = list_entry(dev->delayed_cmd_list.next,
2284                                  struct se_cmd, se_delayed_node);
2285
2286                 if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2287                         /*
2288                          * Check if we started with:
2289                          * [ordered] [simple] [ordered]
2290                          * and we are now at the last ordered so we have to wait
2291                          * for the simple cmd.
2292                          */
2293                         if (atomic_read(&dev->non_ordered) > 0)
2294                                 break;
2295
2296                         dev->ordered_sync_in_progress = true;
2297                 }
2298
2299                 list_del(&cmd->se_delayed_node);
2300                 atomic_dec_mb(&dev->delayed_cmd_count);
2301                 spin_unlock(&dev->delayed_cmd_lock);
2302
2303                 if (cmd->sam_task_attr != TCM_ORDERED_TAG)
2304                         atomic_inc_mb(&dev->non_ordered);
2305
2306                 cmd->transport_state |= CMD_T_SENT;
2307
2308                 __target_execute_cmd(cmd, true);
2309
2310                 spin_lock(&dev->delayed_cmd_lock);
2311         }
2312         spin_unlock(&dev->delayed_cmd_lock);
2313 }
2314
2315 /*
2316  * Called from I/O completion to determine which dormant/delayed
2317  * and ordered cmds need to have their tasks added to the execution queue.
2318  */
2319 static void transport_complete_task_attr(struct se_cmd *cmd)
2320 {
2321         struct se_device *dev = cmd->se_dev;
2322
2323         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2324                 return;
2325
2326         if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2327                 goto restart;
2328
2329         if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
2330                 atomic_dec_mb(&dev->non_ordered);
2331                 dev->dev_cur_ordered_id++;
2332         } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
2333                 atomic_dec_mb(&dev->non_ordered);
2334                 dev->dev_cur_ordered_id++;
2335                 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
2336                          dev->dev_cur_ordered_id);
2337         } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
2338                 spin_lock(&dev->delayed_cmd_lock);
2339                 dev->ordered_sync_in_progress = false;
2340                 spin_unlock(&dev->delayed_cmd_lock);
2341
2342                 dev->dev_cur_ordered_id++;
2343                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
2344                          dev->dev_cur_ordered_id);
2345         }
2346         cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2347
2348 restart:
2349         if (atomic_read(&dev->delayed_cmd_count) > 0)
2350                 schedule_work(&dev->delayed_cmd_work);
2351 }
2352
2353 static void transport_complete_qf(struct se_cmd *cmd)
2354 {
2355         int ret = 0;
2356
2357         transport_complete_task_attr(cmd);
2358         /*
2359          * If a fabric driver ->write_pending() or ->queue_data_in() callback
2360          * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2361          * the same callbacks should not be retried.  Return CHECK_CONDITION
2362          * if a scsi_status is not already set.
2363          *
2364          * If a fabric driver ->queue_status() has returned non zero, always
2365          * keep retrying no matter what..
2366          */
2367         if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2368                 if (cmd->scsi_status)
2369                         goto queue_status;
2370
2371                 translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2372                 goto queue_status;
2373         }
2374
2375         /*
2376          * Check if we need to send a sense buffer from
2377          * the struct se_cmd in question. We do NOT want
2378          * to take this path of the IO has been marked as
2379          * needing to be treated like a "normal read". This
2380          * is the case if it's a tape read, and either the
2381          * FM, EOM, or ILI bits are set, but there is no
2382          * sense data.
2383          */
2384         if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2385             cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2386                 goto queue_status;
2387
2388         switch (cmd->data_direction) {
2389         case DMA_FROM_DEVICE:
2390                 /* queue status if not treating this as a normal read */
2391                 if (cmd->scsi_status &&
2392                     !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2393                         goto queue_status;
2394
2395                 trace_target_cmd_complete(cmd);
2396                 ret = cmd->se_tfo->queue_data_in(cmd);
2397                 break;
2398         case DMA_TO_DEVICE:
2399                 if (cmd->se_cmd_flags & SCF_BIDI) {
2400                         ret = cmd->se_tfo->queue_data_in(cmd);
2401                         break;
2402                 }
2403                 fallthrough;
2404         case DMA_NONE:
2405 queue_status:
2406                 trace_target_cmd_complete(cmd);
2407                 ret = cmd->se_tfo->queue_status(cmd);
2408                 break;
2409         default:
2410                 break;
2411         }
2412
2413         if (ret < 0) {
2414                 transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2415                 return;
2416         }
2417         transport_lun_remove_cmd(cmd);
2418         transport_cmd_check_stop_to_fabric(cmd);
2419 }
2420
2421 static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2422                                         int err, bool write_pending)
2423 {
2424         /*
2425          * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2426          * ->queue_data_in() callbacks from new process context.
2427          *
2428          * Otherwise for other errors, transport_complete_qf() will send
2429          * CHECK_CONDITION via ->queue_status() instead of attempting to
2430          * retry associated fabric driver data-transfer callbacks.
2431          */
2432         if (err == -EAGAIN || err == -ENOMEM) {
2433                 cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2434                                                  TRANSPORT_COMPLETE_QF_OK;
2435         } else {
2436                 pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2437                 cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2438         }
2439
2440         spin_lock_irq(&dev->qf_cmd_lock);
2441         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2442         atomic_inc_mb(&dev->dev_qf_count);
2443         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2444
2445         schedule_work(&cmd->se_dev->qf_work_queue);
2446 }
2447
2448 static bool target_read_prot_action(struct se_cmd *cmd)
2449 {
2450         switch (cmd->prot_op) {
2451         case TARGET_PROT_DIN_STRIP:
2452                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2453                         u32 sectors = cmd->data_length >>
2454                                   ilog2(cmd->se_dev->dev_attrib.block_size);
2455
2456                         cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2457                                                      sectors, 0, cmd->t_prot_sg,
2458                                                      0);
2459                         if (cmd->pi_err)
2460                                 return true;
2461                 }
2462                 break;
2463         case TARGET_PROT_DIN_INSERT:
2464                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2465                         break;
2466
2467                 sbc_dif_generate(cmd);
2468                 break;
2469         default:
2470                 break;
2471         }
2472
2473         return false;
2474 }
2475
2476 static void target_complete_ok_work(struct work_struct *work)
2477 {
2478         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2479         int ret;
2480
2481         /*
2482          * Check if we need to move delayed/dormant tasks from cmds on the
2483          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2484          * Attribute.
2485          */
2486         transport_complete_task_attr(cmd);
2487
2488         /*
2489          * Check to schedule QUEUE_FULL work, or execute an existing
2490          * cmd->transport_qf_callback()
2491          */
2492         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2493                 schedule_work(&cmd->se_dev->qf_work_queue);
2494
2495         /*
2496          * Check if we need to send a sense buffer from
2497          * the struct se_cmd in question. We do NOT want
2498          * to take this path of the IO has been marked as
2499          * needing to be treated like a "normal read". This
2500          * is the case if it's a tape read, and either the
2501          * FM, EOM, or ILI bits are set, but there is no
2502          * sense data.
2503          */
2504         if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2505             cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2506                 WARN_ON(!cmd->scsi_status);
2507                 ret = transport_send_check_condition_and_sense(
2508                                         cmd, 0, 1);
2509                 if (ret)
2510                         goto queue_full;
2511
2512                 transport_lun_remove_cmd(cmd);
2513                 transport_cmd_check_stop_to_fabric(cmd);
2514                 return;
2515         }
2516         /*
2517          * Check for a callback, used by amongst other things
2518          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2519          */
2520         if (cmd->transport_complete_callback) {
2521                 sense_reason_t rc;
2522                 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2523                 bool zero_dl = !(cmd->data_length);
2524                 int post_ret = 0;
2525
2526                 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2527                 if (!rc && !post_ret) {
2528                         if (caw && zero_dl)
2529                                 goto queue_rsp;
2530
2531                         return;
2532                 } else if (rc) {
2533                         ret = transport_send_check_condition_and_sense(cmd,
2534                                                 rc, 0);
2535                         if (ret)
2536                                 goto queue_full;
2537
2538                         transport_lun_remove_cmd(cmd);
2539                         transport_cmd_check_stop_to_fabric(cmd);
2540                         return;
2541                 }
2542         }
2543
2544 queue_rsp:
2545         switch (cmd->data_direction) {
2546         case DMA_FROM_DEVICE:
2547                 /*
2548                  * if this is a READ-type IO, but SCSI status
2549                  * is set, then skip returning data and just
2550                  * return the status -- unless this IO is marked
2551                  * as needing to be treated as a normal read,
2552                  * in which case we want to go ahead and return
2553                  * the data. This happens, for example, for tape
2554                  * reads with the FM, EOM, or ILI bits set, with
2555                  * no sense data.
2556                  */
2557                 if (cmd->scsi_status &&
2558                     !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2559                         goto queue_status;
2560
2561                 atomic_long_add(cmd->data_length,
2562                                 &cmd->se_lun->lun_stats.tx_data_octets);
2563                 /*
2564                  * Perform READ_STRIP of PI using software emulation when
2565                  * backend had PI enabled, if the transport will not be
2566                  * performing hardware READ_STRIP offload.
2567                  */
2568                 if (target_read_prot_action(cmd)) {
2569                         ret = transport_send_check_condition_and_sense(cmd,
2570                                                 cmd->pi_err, 0);
2571                         if (ret)
2572                                 goto queue_full;
2573
2574                         transport_lun_remove_cmd(cmd);
2575                         transport_cmd_check_stop_to_fabric(cmd);
2576                         return;
2577                 }
2578
2579                 trace_target_cmd_complete(cmd);
2580                 ret = cmd->se_tfo->queue_data_in(cmd);
2581                 if (ret)
2582                         goto queue_full;
2583                 break;
2584         case DMA_TO_DEVICE:
2585                 atomic_long_add(cmd->data_length,
2586                                 &cmd->se_lun->lun_stats.rx_data_octets);
2587                 /*
2588                  * Check if we need to send READ payload for BIDI-COMMAND
2589                  */
2590                 if (cmd->se_cmd_flags & SCF_BIDI) {
2591                         atomic_long_add(cmd->data_length,
2592                                         &cmd->se_lun->lun_stats.tx_data_octets);
2593                         ret = cmd->se_tfo->queue_data_in(cmd);
2594                         if (ret)
2595                                 goto queue_full;
2596                         break;
2597                 }
2598                 fallthrough;
2599         case DMA_NONE:
2600 queue_status:
2601                 trace_target_cmd_complete(cmd);
2602                 ret = cmd->se_tfo->queue_status(cmd);
2603                 if (ret)
2604                         goto queue_full;
2605                 break;
2606         default:
2607                 break;
2608         }
2609
2610         transport_lun_remove_cmd(cmd);
2611         transport_cmd_check_stop_to_fabric(cmd);
2612         return;
2613
2614 queue_full:
2615         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2616                 " data_direction: %d\n", cmd, cmd->data_direction);
2617
2618         transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2619 }
2620
2621 void target_free_sgl(struct scatterlist *sgl, int nents)
2622 {
2623         sgl_free_n_order(sgl, nents, 0);
2624 }
2625 EXPORT_SYMBOL(target_free_sgl);
2626
2627 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2628 {
2629         /*
2630          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2631          * emulation, and free + reset pointers if necessary..
2632          */
2633         if (!cmd->t_data_sg_orig)
2634                 return;
2635
2636         kfree(cmd->t_data_sg);
2637         cmd->t_data_sg = cmd->t_data_sg_orig;
2638         cmd->t_data_sg_orig = NULL;
2639         cmd->t_data_nents = cmd->t_data_nents_orig;
2640         cmd->t_data_nents_orig = 0;
2641 }
2642
2643 static inline void transport_free_pages(struct se_cmd *cmd)
2644 {
2645         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2646                 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2647                 cmd->t_prot_sg = NULL;
2648                 cmd->t_prot_nents = 0;
2649         }
2650
2651         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2652                 /*
2653                  * Release special case READ buffer payload required for
2654                  * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2655                  */
2656                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2657                         target_free_sgl(cmd->t_bidi_data_sg,
2658                                            cmd->t_bidi_data_nents);
2659                         cmd->t_bidi_data_sg = NULL;
2660                         cmd->t_bidi_data_nents = 0;
2661                 }
2662                 transport_reset_sgl_orig(cmd);
2663                 return;
2664         }
2665         transport_reset_sgl_orig(cmd);
2666
2667         target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2668         cmd->t_data_sg = NULL;
2669         cmd->t_data_nents = 0;
2670
2671         target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2672         cmd->t_bidi_data_sg = NULL;
2673         cmd->t_bidi_data_nents = 0;
2674 }
2675
2676 void *transport_kmap_data_sg(struct se_cmd *cmd)
2677 {
2678         struct scatterlist *sg = cmd->t_data_sg;
2679         struct page **pages;
2680         int i;
2681
2682         /*
2683          * We need to take into account a possible offset here for fabrics like
2684          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2685          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2686          */
2687         if (!cmd->t_data_nents)
2688                 return NULL;
2689
2690         BUG_ON(!sg);
2691         if (cmd->t_data_nents == 1)
2692                 return kmap(sg_page(sg)) + sg->offset;
2693
2694         /* >1 page. use vmap */
2695         pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2696         if (!pages)
2697                 return NULL;
2698
2699         /* convert sg[] to pages[] */
2700         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2701                 pages[i] = sg_page(sg);
2702         }
2703
2704         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2705         kfree(pages);
2706         if (!cmd->t_data_vmap)
2707                 return NULL;
2708
2709         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2710 }
2711 EXPORT_SYMBOL(transport_kmap_data_sg);
2712
2713 void transport_kunmap_data_sg(struct se_cmd *cmd)
2714 {
2715         if (!cmd->t_data_nents) {
2716                 return;
2717         } else if (cmd->t_data_nents == 1) {
2718                 kunmap(sg_page(cmd->t_data_sg));
2719                 return;
2720         }
2721
2722         vunmap(cmd->t_data_vmap);
2723         cmd->t_data_vmap = NULL;
2724 }
2725 EXPORT_SYMBOL(transport_kunmap_data_sg);
2726
2727 int
2728 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2729                  bool zero_page, bool chainable)
2730 {
2731         gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2732
2733         *sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2734         return *sgl ? 0 : -ENOMEM;
2735 }
2736 EXPORT_SYMBOL(target_alloc_sgl);
2737
2738 /*
2739  * Allocate any required resources to execute the command.  For writes we
2740  * might not have the payload yet, so notify the fabric via a call to
2741  * ->write_pending instead. Otherwise place it on the execution queue.
2742  */
2743 sense_reason_t
2744 transport_generic_new_cmd(struct se_cmd *cmd)
2745 {
2746         unsigned long flags;
2747         int ret = 0;
2748         bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2749
2750         if (cmd->prot_op != TARGET_PROT_NORMAL &&
2751             !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2752                 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2753                                        cmd->prot_length, true, false);
2754                 if (ret < 0)
2755                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2756         }
2757
2758         /*
2759          * Determine if the TCM fabric module has already allocated physical
2760          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2761          * beforehand.
2762          */
2763         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2764             cmd->data_length) {
2765
2766                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2767                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2768                         u32 bidi_length;
2769
2770                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2771                                 bidi_length = cmd->t_task_nolb *
2772                                               cmd->se_dev->dev_attrib.block_size;
2773                         else
2774                                 bidi_length = cmd->data_length;
2775
2776                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2777                                                &cmd->t_bidi_data_nents,
2778                                                bidi_length, zero_flag, false);
2779                         if (ret < 0)
2780                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2781                 }
2782
2783                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2784                                        cmd->data_length, zero_flag, false);
2785                 if (ret < 0)
2786                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2787         } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2788                     cmd->data_length) {
2789                 /*
2790                  * Special case for COMPARE_AND_WRITE with fabrics
2791                  * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2792                  */
2793                 u32 caw_length = cmd->t_task_nolb *
2794                                  cmd->se_dev->dev_attrib.block_size;
2795
2796                 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2797                                        &cmd->t_bidi_data_nents,
2798                                        caw_length, zero_flag, false);
2799                 if (ret < 0)
2800                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2801         }
2802         /*
2803          * If this command is not a write we can execute it right here,
2804          * for write buffers we need to notify the fabric driver first
2805          * and let it call back once the write buffers are ready.
2806          */
2807         target_add_to_state_list(cmd);
2808         if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2809                 target_execute_cmd(cmd);
2810                 return 0;
2811         }
2812
2813         spin_lock_irqsave(&cmd->t_state_lock, flags);
2814         cmd->t_state = TRANSPORT_WRITE_PENDING;
2815         /*
2816          * Determine if frontend context caller is requesting the stopping of
2817          * this command for frontend exceptions.
2818          */
2819         if (cmd->transport_state & CMD_T_STOP &&
2820             !cmd->se_tfo->write_pending_must_be_called) {
2821                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2822                          __func__, __LINE__, cmd->tag);
2823
2824                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2825
2826                 complete_all(&cmd->t_transport_stop_comp);
2827                 return 0;
2828         }
2829         cmd->transport_state &= ~CMD_T_ACTIVE;
2830         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2831
2832         ret = cmd->se_tfo->write_pending(cmd);
2833         if (ret)
2834                 goto queue_full;
2835
2836         return 0;
2837
2838 queue_full:
2839         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2840         transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2841         return 0;
2842 }
2843 EXPORT_SYMBOL(transport_generic_new_cmd);
2844
2845 static void transport_write_pending_qf(struct se_cmd *cmd)
2846 {
2847         unsigned long flags;
2848         int ret;
2849         bool stop;
2850
2851         spin_lock_irqsave(&cmd->t_state_lock, flags);
2852         stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2853         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2854
2855         if (stop) {
2856                 pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2857                         __func__, __LINE__, cmd->tag);
2858                 complete_all(&cmd->t_transport_stop_comp);
2859                 return;
2860         }
2861
2862         ret = cmd->se_tfo->write_pending(cmd);
2863         if (ret) {
2864                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2865                          cmd);
2866                 transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2867         }
2868 }
2869
2870 static bool
2871 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2872                            unsigned long *flags);
2873
2874 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2875 {
2876         unsigned long flags;
2877
2878         spin_lock_irqsave(&cmd->t_state_lock, flags);
2879         __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2880         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2881 }
2882
2883 /*
2884  * Call target_put_sess_cmd() and wait until target_release_cmd_kref(@cmd) has
2885  * finished.
2886  */
2887 void target_put_cmd_and_wait(struct se_cmd *cmd)
2888 {
2889         DECLARE_COMPLETION_ONSTACK(compl);
2890
2891         WARN_ON_ONCE(cmd->abrt_compl);
2892         cmd->abrt_compl = &compl;
2893         target_put_sess_cmd(cmd);
2894         wait_for_completion(&compl);
2895 }
2896
2897 /*
2898  * This function is called by frontend drivers after processing of a command
2899  * has finished.
2900  *
2901  * The protocol for ensuring that either the regular frontend command
2902  * processing flow or target_handle_abort() code drops one reference is as
2903  * follows:
2904  * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
2905  *   the frontend driver to call this function synchronously or asynchronously.
2906  *   That will cause one reference to be dropped.
2907  * - During regular command processing the target core sets CMD_T_COMPLETE
2908  *   before invoking one of the .queue_*() functions.
2909  * - The code that aborts commands skips commands and TMFs for which
2910  *   CMD_T_COMPLETE has been set.
2911  * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
2912  *   commands that will be aborted.
2913  * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
2914  *   transport_generic_free_cmd() skips its call to target_put_sess_cmd().
2915  * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
2916  *   be called and will drop a reference.
2917  * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
2918  *   will be called. target_handle_abort() will drop the final reference.
2919  */
2920 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2921 {
2922         DECLARE_COMPLETION_ONSTACK(compl);
2923         int ret = 0;
2924         bool aborted = false, tas = false;
2925
2926         if (wait_for_tasks)
2927                 target_wait_free_cmd(cmd, &aborted, &tas);
2928
2929         if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
2930                 /*
2931                  * Handle WRITE failure case where transport_generic_new_cmd()
2932                  * has already added se_cmd to state_list, but fabric has
2933                  * failed command before I/O submission.
2934                  */
2935                 if (cmd->state_active)
2936                         target_remove_from_state_list(cmd);
2937
2938                 if (cmd->se_lun)
2939                         transport_lun_remove_cmd(cmd);
2940         }
2941         if (aborted)
2942                 cmd->free_compl = &compl;
2943         ret = target_put_sess_cmd(cmd);
2944         if (aborted) {
2945                 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2946                 wait_for_completion(&compl);
2947                 ret = 1;
2948         }
2949         return ret;
2950 }
2951 EXPORT_SYMBOL(transport_generic_free_cmd);
2952
2953 /**
2954  * target_get_sess_cmd - Verify the session is accepting cmds and take ref
2955  * @se_cmd:     command descriptor to add
2956  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2957  */
2958 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2959 {
2960         struct se_session *se_sess = se_cmd->se_sess;
2961         int ret = 0;
2962
2963         /*
2964          * Add a second kref if the fabric caller is expecting to handle
2965          * fabric acknowledgement that requires two target_put_sess_cmd()
2966          * invocations before se_cmd descriptor release.
2967          */
2968         if (ack_kref) {
2969                 kref_get(&se_cmd->cmd_kref);
2970                 se_cmd->se_cmd_flags |= SCF_ACK_KREF;
2971         }
2972
2973         if (!percpu_ref_tryget_live(&se_sess->cmd_count))
2974                 ret = -ESHUTDOWN;
2975
2976         if (ret && ack_kref)
2977                 target_put_sess_cmd(se_cmd);
2978
2979         return ret;
2980 }
2981 EXPORT_SYMBOL(target_get_sess_cmd);
2982
2983 static void target_free_cmd_mem(struct se_cmd *cmd)
2984 {
2985         transport_free_pages(cmd);
2986
2987         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2988                 core_tmr_release_req(cmd->se_tmr_req);
2989         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2990                 kfree(cmd->t_task_cdb);
2991 }
2992
2993 static void target_release_cmd_kref(struct kref *kref)
2994 {
2995         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2996         struct se_session *se_sess = se_cmd->se_sess;
2997         struct completion *free_compl = se_cmd->free_compl;
2998         struct completion *abrt_compl = se_cmd->abrt_compl;
2999
3000         target_free_cmd_mem(se_cmd);
3001         se_cmd->se_tfo->release_cmd(se_cmd);
3002         if (free_compl)
3003                 complete(free_compl);
3004         if (abrt_compl)
3005                 complete(abrt_compl);
3006
3007         percpu_ref_put(&se_sess->cmd_count);
3008 }
3009
3010 /**
3011  * target_put_sess_cmd - decrease the command reference count
3012  * @se_cmd:     command to drop a reference from
3013  *
3014  * Returns 1 if and only if this target_put_sess_cmd() call caused the
3015  * refcount to drop to zero. Returns zero otherwise.
3016  */
3017 int target_put_sess_cmd(struct se_cmd *se_cmd)
3018 {
3019         return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
3020 }
3021 EXPORT_SYMBOL(target_put_sess_cmd);
3022
3023 static const char *data_dir_name(enum dma_data_direction d)
3024 {
3025         switch (d) {
3026         case DMA_BIDIRECTIONAL: return "BIDI";
3027         case DMA_TO_DEVICE:     return "WRITE";
3028         case DMA_FROM_DEVICE:   return "READ";
3029         case DMA_NONE:          return "NONE";
3030         }
3031
3032         return "(?)";
3033 }
3034
3035 static const char *cmd_state_name(enum transport_state_table t)
3036 {
3037         switch (t) {
3038         case TRANSPORT_NO_STATE:        return "NO_STATE";
3039         case TRANSPORT_NEW_CMD:         return "NEW_CMD";
3040         case TRANSPORT_WRITE_PENDING:   return "WRITE_PENDING";
3041         case TRANSPORT_PROCESSING:      return "PROCESSING";
3042         case TRANSPORT_COMPLETE:        return "COMPLETE";
3043         case TRANSPORT_ISTATE_PROCESSING:
3044                                         return "ISTATE_PROCESSING";
3045         case TRANSPORT_COMPLETE_QF_WP:  return "COMPLETE_QF_WP";
3046         case TRANSPORT_COMPLETE_QF_OK:  return "COMPLETE_QF_OK";
3047         case TRANSPORT_COMPLETE_QF_ERR: return "COMPLETE_QF_ERR";
3048         }
3049
3050         return "(?)";
3051 }
3052
3053 static void target_append_str(char **str, const char *txt)
3054 {
3055         char *prev = *str;
3056
3057         *str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
3058                 kstrdup(txt, GFP_ATOMIC);
3059         kfree(prev);
3060 }
3061
3062 /*
3063  * Convert a transport state bitmask into a string. The caller is
3064  * responsible for freeing the returned pointer.
3065  */
3066 static char *target_ts_to_str(u32 ts)
3067 {
3068         char *str = NULL;
3069
3070         if (ts & CMD_T_ABORTED)
3071                 target_append_str(&str, "aborted");
3072         if (ts & CMD_T_ACTIVE)
3073                 target_append_str(&str, "active");
3074         if (ts & CMD_T_COMPLETE)
3075                 target_append_str(&str, "complete");
3076         if (ts & CMD_T_SENT)
3077                 target_append_str(&str, "sent");
3078         if (ts & CMD_T_STOP)
3079                 target_append_str(&str, "stop");
3080         if (ts & CMD_T_FABRIC_STOP)
3081                 target_append_str(&str, "fabric_stop");
3082
3083         return str;
3084 }
3085
3086 static const char *target_tmf_name(enum tcm_tmreq_table tmf)
3087 {
3088         switch (tmf) {
3089         case TMR_ABORT_TASK:            return "ABORT_TASK";
3090         case TMR_ABORT_TASK_SET:        return "ABORT_TASK_SET";
3091         case TMR_CLEAR_ACA:             return "CLEAR_ACA";
3092         case TMR_CLEAR_TASK_SET:        return "CLEAR_TASK_SET";
3093         case TMR_LUN_RESET:             return "LUN_RESET";
3094         case TMR_TARGET_WARM_RESET:     return "TARGET_WARM_RESET";
3095         case TMR_TARGET_COLD_RESET:     return "TARGET_COLD_RESET";
3096         case TMR_LUN_RESET_PRO:         return "LUN_RESET_PRO";
3097         case TMR_UNKNOWN:               break;
3098         }
3099         return "(?)";
3100 }
3101
3102 void target_show_cmd(const char *pfx, struct se_cmd *cmd)
3103 {
3104         char *ts_str = target_ts_to_str(cmd->transport_state);
3105         const u8 *cdb = cmd->t_task_cdb;
3106         struct se_tmr_req *tmf = cmd->se_tmr_req;
3107
3108         if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
3109                 pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
3110                          pfx, cdb[0], cdb[1], cmd->tag,
3111                          data_dir_name(cmd->data_direction),
3112                          cmd->se_tfo->get_cmd_state(cmd),
3113                          cmd_state_name(cmd->t_state), cmd->data_length,
3114                          kref_read(&cmd->cmd_kref), ts_str);
3115         } else {
3116                 pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
3117                          pfx, target_tmf_name(tmf->function), cmd->tag,
3118                          tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
3119                          cmd_state_name(cmd->t_state),
3120                          kref_read(&cmd->cmd_kref), ts_str);
3121         }
3122         kfree(ts_str);
3123 }
3124 EXPORT_SYMBOL(target_show_cmd);
3125
3126 static void target_stop_session_confirm(struct percpu_ref *ref)
3127 {
3128         struct se_session *se_sess = container_of(ref, struct se_session,
3129                                                   cmd_count);
3130         complete_all(&se_sess->stop_done);
3131 }
3132
3133 /**
3134  * target_stop_session - Stop new IO from being queued on the session.
3135  * @se_sess:    session to stop
3136  */
3137 void target_stop_session(struct se_session *se_sess)
3138 {
3139         pr_debug("Stopping session queue.\n");
3140         if (atomic_cmpxchg(&se_sess->stopped, 0, 1) == 0)
3141                 percpu_ref_kill_and_confirm(&se_sess->cmd_count,
3142                                             target_stop_session_confirm);
3143 }
3144 EXPORT_SYMBOL(target_stop_session);
3145
3146 /**
3147  * target_wait_for_sess_cmds - Wait for outstanding commands
3148  * @se_sess:    session to wait for active I/O
3149  */
3150 void target_wait_for_sess_cmds(struct se_session *se_sess)
3151 {
3152         int ret;
3153
3154         WARN_ON_ONCE(!atomic_read(&se_sess->stopped));
3155
3156         do {
3157                 pr_debug("Waiting for running cmds to complete.\n");
3158                 ret = wait_event_timeout(se_sess->cmd_count_wq,
3159                                 percpu_ref_is_zero(&se_sess->cmd_count),
3160                                 180 * HZ);
3161         } while (ret <= 0);
3162
3163         wait_for_completion(&se_sess->stop_done);
3164         pr_debug("Waiting for cmds done.\n");
3165 }
3166 EXPORT_SYMBOL(target_wait_for_sess_cmds);
3167
3168 /*
3169  * Prevent that new percpu_ref_tryget_live() calls succeed and wait until
3170  * all references to the LUN have been released. Called during LUN shutdown.
3171  */
3172 void transport_clear_lun_ref(struct se_lun *lun)
3173 {
3174         percpu_ref_kill(&lun->lun_ref);
3175         wait_for_completion(&lun->lun_shutdown_comp);
3176 }
3177
3178 static bool
3179 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
3180                            bool *aborted, bool *tas, unsigned long *flags)
3181         __releases(&cmd->t_state_lock)
3182         __acquires(&cmd->t_state_lock)
3183 {
3184         lockdep_assert_held(&cmd->t_state_lock);
3185
3186         if (fabric_stop)
3187                 cmd->transport_state |= CMD_T_FABRIC_STOP;
3188
3189         if (cmd->transport_state & CMD_T_ABORTED)
3190                 *aborted = true;
3191
3192         if (cmd->transport_state & CMD_T_TAS)
3193                 *tas = true;
3194
3195         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
3196             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3197                 return false;
3198
3199         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
3200             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3201                 return false;
3202
3203         if (!(cmd->transport_state & CMD_T_ACTIVE))
3204                 return false;
3205
3206         if (fabric_stop && *aborted)
3207                 return false;
3208
3209         cmd->transport_state |= CMD_T_STOP;
3210
3211         target_show_cmd("wait_for_tasks: Stopping ", cmd);
3212
3213         spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
3214
3215         while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
3216                                             180 * HZ))
3217                 target_show_cmd("wait for tasks: ", cmd);
3218
3219         spin_lock_irqsave(&cmd->t_state_lock, *flags);
3220         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
3221
3222         pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
3223                  "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
3224
3225         return true;
3226 }
3227
3228 /**
3229  * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
3230  * @cmd: command to wait on
3231  */
3232 bool transport_wait_for_tasks(struct se_cmd *cmd)
3233 {
3234         unsigned long flags;
3235         bool ret, aborted = false, tas = false;
3236
3237         spin_lock_irqsave(&cmd->t_state_lock, flags);
3238         ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
3239         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3240
3241         return ret;
3242 }
3243 EXPORT_SYMBOL(transport_wait_for_tasks);
3244
3245 struct sense_detail {
3246         u8 key;
3247         u8 asc;
3248         u8 ascq;
3249         bool add_sense_info;
3250 };
3251
3252 static const struct sense_detail sense_detail_table[] = {
3253         [TCM_NO_SENSE] = {
3254                 .key = NOT_READY
3255         },
3256         [TCM_NON_EXISTENT_LUN] = {
3257                 .key = ILLEGAL_REQUEST,
3258                 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
3259         },
3260         [TCM_UNSUPPORTED_SCSI_OPCODE] = {
3261                 .key = ILLEGAL_REQUEST,
3262                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3263         },
3264         [TCM_SECTOR_COUNT_TOO_MANY] = {
3265                 .key = ILLEGAL_REQUEST,
3266                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3267         },
3268         [TCM_UNKNOWN_MODE_PAGE] = {
3269                 .key = ILLEGAL_REQUEST,
3270                 .asc = 0x24, /* INVALID FIELD IN CDB */
3271         },
3272         [TCM_CHECK_CONDITION_ABORT_CMD] = {
3273                 .key = ABORTED_COMMAND,
3274                 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3275                 .ascq = 0x03,
3276         },
3277         [TCM_INCORRECT_AMOUNT_OF_DATA] = {
3278                 .key = ABORTED_COMMAND,
3279                 .asc = 0x0c, /* WRITE ERROR */
3280                 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3281         },
3282         [TCM_INVALID_CDB_FIELD] = {
3283                 .key = ILLEGAL_REQUEST,
3284                 .asc = 0x24, /* INVALID FIELD IN CDB */
3285         },
3286         [TCM_INVALID_PARAMETER_LIST] = {
3287                 .key = ILLEGAL_REQUEST,
3288                 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3289         },
3290         [TCM_TOO_MANY_TARGET_DESCS] = {
3291                 .key = ILLEGAL_REQUEST,
3292                 .asc = 0x26,
3293                 .ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3294         },
3295         [TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3296                 .key = ILLEGAL_REQUEST,
3297                 .asc = 0x26,
3298                 .ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3299         },
3300         [TCM_TOO_MANY_SEGMENT_DESCS] = {
3301                 .key = ILLEGAL_REQUEST,
3302                 .asc = 0x26,
3303                 .ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3304         },
3305         [TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3306                 .key = ILLEGAL_REQUEST,
3307                 .asc = 0x26,
3308                 .ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3309         },
3310         [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3311                 .key = ILLEGAL_REQUEST,
3312                 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3313         },
3314         [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3315                 .key = ILLEGAL_REQUEST,
3316                 .asc = 0x0c, /* WRITE ERROR */
3317                 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3318         },
3319         [TCM_SERVICE_CRC_ERROR] = {
3320                 .key = ABORTED_COMMAND,
3321                 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3322                 .ascq = 0x05, /* N/A */
3323         },
3324         [TCM_SNACK_REJECTED] = {
3325                 .key = ABORTED_COMMAND,
3326                 .asc = 0x11, /* READ ERROR */
3327                 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3328         },
3329         [TCM_WRITE_PROTECTED] = {
3330                 .key = DATA_PROTECT,
3331                 .asc = 0x27, /* WRITE PROTECTED */
3332         },
3333         [TCM_ADDRESS_OUT_OF_RANGE] = {
3334                 .key = ILLEGAL_REQUEST,
3335                 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3336         },
3337         [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3338                 .key = UNIT_ATTENTION,
3339         },
3340         [TCM_MISCOMPARE_VERIFY] = {
3341                 .key = MISCOMPARE,
3342                 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3343                 .ascq = 0x00,
3344                 .add_sense_info = true,
3345         },
3346         [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
3347                 .key = ABORTED_COMMAND,
3348                 .asc = 0x10,
3349                 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
3350                 .add_sense_info = true,
3351         },
3352         [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
3353                 .key = ABORTED_COMMAND,
3354                 .asc = 0x10,
3355                 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
3356                 .add_sense_info = true,
3357         },
3358         [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
3359                 .key = ABORTED_COMMAND,
3360                 .asc = 0x10,
3361                 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
3362                 .add_sense_info = true,
3363         },
3364         [TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
3365                 .key = COPY_ABORTED,
3366                 .asc = 0x0d,
3367                 .ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
3368
3369         },
3370         [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
3371                 /*
3372                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
3373                  * Solaris initiators.  Returning NOT READY instead means the
3374                  * operations will be retried a finite number of times and we
3375                  * can survive intermittent errors.
3376                  */
3377                 .key = NOT_READY,
3378                 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
3379         },
3380         [TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
3381                 /*
3382                  * From spc4r22 section5.7.7,5.7.8
3383                  * If a PERSISTENT RESERVE OUT command with a REGISTER service action
3384                  * or a REGISTER AND IGNORE EXISTING KEY service action or
3385                  * REGISTER AND MOVE service actionis attempted,
3386                  * but there are insufficient device server resources to complete the
3387                  * operation, then the command shall be terminated with CHECK CONDITION
3388                  * status, with the sense key set to ILLEGAL REQUEST,and the additonal
3389                  * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
3390                  */
3391                 .key = ILLEGAL_REQUEST,
3392                 .asc = 0x55,
3393                 .ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
3394         },
3395         [TCM_INVALID_FIELD_IN_COMMAND_IU] = {
3396                 .key = ILLEGAL_REQUEST,
3397                 .asc = 0x0e,
3398                 .ascq = 0x03, /* INVALID FIELD IN COMMAND INFORMATION UNIT */
3399         },
3400         [TCM_ALUA_TG_PT_STANDBY] = {
3401                 .key = NOT_READY,
3402                 .asc = 0x04,
3403                 .ascq = ASCQ_04H_ALUA_TG_PT_STANDBY,
3404         },
3405         [TCM_ALUA_TG_PT_UNAVAILABLE] = {
3406                 .key = NOT_READY,
3407                 .asc = 0x04,
3408                 .ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE,
3409         },
3410         [TCM_ALUA_STATE_TRANSITION] = {
3411                 .key = NOT_READY,
3412                 .asc = 0x04,
3413                 .ascq = ASCQ_04H_ALUA_STATE_TRANSITION,
3414         },
3415         [TCM_ALUA_OFFLINE] = {
3416                 .key = NOT_READY,
3417                 .asc = 0x04,
3418                 .ascq = ASCQ_04H_ALUA_OFFLINE,
3419         },
3420 };
3421
3422 /**
3423  * translate_sense_reason - translate a sense reason into T10 key, asc and ascq
3424  * @cmd: SCSI command in which the resulting sense buffer or SCSI status will
3425  *   be stored.
3426  * @reason: LIO sense reason code. If this argument has the value
3427  *   TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If
3428  *   dequeuing a unit attention fails due to multiple commands being processed
3429  *   concurrently, set the command status to BUSY.
3430  *
3431  * Return: 0 upon success or -EINVAL if the sense buffer is too small.
3432  */
3433 static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
3434 {
3435         const struct sense_detail *sd;
3436         u8 *buffer = cmd->sense_buffer;
3437         int r = (__force int)reason;
3438         u8 key, asc, ascq;
3439         bool desc_format = target_sense_desc_format(cmd->se_dev);
3440
3441         if (r < ARRAY_SIZE(sense_detail_table) && sense_detail_table[r].key)
3442                 sd = &sense_detail_table[r];
3443         else
3444                 sd = &sense_detail_table[(__force int)
3445                                        TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3446
3447         key = sd->key;
3448         if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
3449                 if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc,
3450                                                        &ascq)) {
3451                         cmd->scsi_status = SAM_STAT_BUSY;
3452                         return;
3453                 }
3454         } else {
3455                 WARN_ON_ONCE(sd->asc == 0);
3456                 asc = sd->asc;
3457                 ascq = sd->ascq;
3458         }
3459
3460         cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
3461         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
3462         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
3463         scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
3464         if (sd->add_sense_info)
3465                 WARN_ON_ONCE(scsi_set_sense_information(buffer,
3466                                                         cmd->scsi_sense_length,
3467                                                         cmd->sense_info) < 0);
3468 }
3469
3470 int
3471 transport_send_check_condition_and_sense(struct se_cmd *cmd,
3472                 sense_reason_t reason, int from_transport)
3473 {
3474         unsigned long flags;
3475
3476         WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3477
3478         spin_lock_irqsave(&cmd->t_state_lock, flags);
3479         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
3480                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3481                 return 0;
3482         }
3483         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
3484         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3485
3486         if (!from_transport)
3487                 translate_sense_reason(cmd, reason);
3488
3489         trace_target_cmd_complete(cmd);
3490         return cmd->se_tfo->queue_status(cmd);
3491 }
3492 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
3493
3494 /**
3495  * target_send_busy - Send SCSI BUSY status back to the initiator
3496  * @cmd: SCSI command for which to send a BUSY reply.
3497  *
3498  * Note: Only call this function if target_submit_cmd*() failed.
3499  */
3500 int target_send_busy(struct se_cmd *cmd)
3501 {
3502         WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3503
3504         cmd->scsi_status = SAM_STAT_BUSY;
3505         trace_target_cmd_complete(cmd);
3506         return cmd->se_tfo->queue_status(cmd);
3507 }
3508 EXPORT_SYMBOL(target_send_busy);
3509
3510 static void target_tmr_work(struct work_struct *work)
3511 {
3512         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3513         struct se_device *dev = cmd->se_dev;
3514         struct se_tmr_req *tmr = cmd->se_tmr_req;
3515         int ret;
3516
3517         if (cmd->transport_state & CMD_T_ABORTED)
3518                 goto aborted;
3519
3520         switch (tmr->function) {
3521         case TMR_ABORT_TASK:
3522                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3523                 break;
3524         case TMR_ABORT_TASK_SET:
3525         case TMR_CLEAR_ACA:
3526         case TMR_CLEAR_TASK_SET:
3527                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3528                 break;
3529         case TMR_LUN_RESET:
3530                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3531                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3532                                          TMR_FUNCTION_REJECTED;
3533                 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3534                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3535                                                cmd->orig_fe_lun, 0x29,
3536                                                ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3537                 }
3538                 break;
3539         case TMR_TARGET_WARM_RESET:
3540                 tmr->response = TMR_FUNCTION_REJECTED;
3541                 break;
3542         case TMR_TARGET_COLD_RESET:
3543                 tmr->response = TMR_FUNCTION_REJECTED;
3544                 break;
3545         default:
3546                 pr_err("Unknown TMR function: 0x%02x.\n",
3547                                 tmr->function);
3548                 tmr->response = TMR_FUNCTION_REJECTED;
3549                 break;
3550         }
3551
3552         if (cmd->transport_state & CMD_T_ABORTED)
3553                 goto aborted;
3554
3555         cmd->se_tfo->queue_tm_rsp(cmd);
3556
3557         transport_lun_remove_cmd(cmd);
3558         transport_cmd_check_stop_to_fabric(cmd);
3559         return;
3560
3561 aborted:
3562         target_handle_abort(cmd);
3563 }
3564
3565 int transport_generic_handle_tmr(
3566         struct se_cmd *cmd)
3567 {
3568         unsigned long flags;
3569         bool aborted = false;
3570
3571         spin_lock_irqsave(&cmd->t_state_lock, flags);
3572         if (cmd->transport_state & CMD_T_ABORTED) {
3573                 aborted = true;
3574         } else {
3575                 cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3576                 cmd->transport_state |= CMD_T_ACTIVE;
3577         }
3578         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3579
3580         if (aborted) {
3581                 pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d ref_tag: %llu tag: %llu\n",
3582                                     cmd->se_tmr_req->function,
3583                                     cmd->se_tmr_req->ref_task_tag, cmd->tag);
3584                 target_handle_abort(cmd);
3585                 return 0;
3586         }
3587
3588         INIT_WORK(&cmd->work, target_tmr_work);
3589         schedule_work(&cmd->work);
3590         return 0;
3591 }
3592 EXPORT_SYMBOL(transport_generic_handle_tmr);
3593
3594 bool
3595 target_check_wce(struct se_device *dev)
3596 {
3597         bool wce = false;
3598
3599         if (dev->transport->get_write_cache)
3600                 wce = dev->transport->get_write_cache(dev);
3601         else if (dev->dev_attrib.emulate_write_cache > 0)
3602                 wce = true;
3603
3604         return wce;
3605 }
3606
3607 bool
3608 target_check_fua(struct se_device *dev)
3609 {
3610         return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3611 }