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