drivers/target/target_core_transport.c

   1 /*******************************************************************************
   2  * Filename:  target_core_transport.c
   3  *
   4  * This file contains the Generic Target Engine Core.
   5  *
   6  * (c) Copyright 2002-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/net.h>
  27 #include <linux/delay.h>
  28 #include <linux/string.h>
  29 #include <linux/timer.h>
  30 #include <linux/slab.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/kthread.h>
  33 #include <linux/in.h>
  34 #include <linux/cdrom.h>
  35 #include <linux/module.h>
  36 #include <linux/ratelimit.h>
  37 #include <asm/unaligned.h>
  38 #include <net/sock.h>
  39 #include <net/tcp.h>
  40 #include <scsi/scsi.h>
  41 #include <scsi/scsi_cmnd.h>
  42 #include <scsi/scsi_tcq.h>
  43
  44 #include <target/target_core_base.h>
  45 #include <target/target_core_backend.h>
  46 #include <target/target_core_fabric.h>
  47 #include <target/target_core_configfs.h>
  48
  49 #include "target_core_internal.h"
  50 #include "target_core_alua.h"
  51 #include "target_core_pr.h"
  52 #include "target_core_ua.h"
  53
  54 #define CREATE_TRACE_POINTS
  55 #include <trace/events/target.h>
  56
  57 static struct workqueue_struct *target_completion_wq;
  58 static struct kmem_cache *se_sess_cache;
  59 struct kmem_cache *se_ua_cache;
  60 struct kmem_cache *t10_pr_reg_cache;
  61 struct kmem_cache *t10_alua_lu_gp_cache;
  62 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  63 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  64 struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
  65 struct kmem_cache *t10_alua_lba_map_cache;
  66 struct kmem_cache *t10_alua_lba_map_mem_cache;
  67
  68 static void transport_complete_task_attr(struct se_cmd *cmd);
  69 static void transport_handle_queue_full(struct se_cmd *cmd,
  70                 struct se_device *dev);
  71 static int transport_put_cmd(struct se_cmd *cmd);
  72 static void target_complete_ok_work(struct work_struct *work);
  73
  74 int init_se_kmem_caches(void)
  75 {
  76         se_sess_cache = kmem_cache_create("se_sess_cache",
  77                         sizeof(struct se_session), __alignof__(struct se_session),
  78                         0, NULL);
  79         if (!se_sess_cache) {
  80                 pr_err("kmem_cache_create() for struct se_session"
  81                                 " failed\n");
  82                 goto out;
  83         }
  84         se_ua_cache = kmem_cache_create("se_ua_cache",
  85                         sizeof(struct se_ua), __alignof__(struct se_ua),
  86                         0, NULL);
  87         if (!se_ua_cache) {
  88                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  89                 goto out_free_sess_cache;
  90         }
  91         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  92                         sizeof(struct t10_pr_registration),
  93                         __alignof__(struct t10_pr_registration), 0, NULL);
  94         if (!t10_pr_reg_cache) {
  95                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  96                                 " failed\n");
  97                 goto out_free_ua_cache;
  98         }
  99         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
 100                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
 101                         0, NULL);
 102         if (!t10_alua_lu_gp_cache) {
 103                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 104                                 " failed\n");
 105                 goto out_free_pr_reg_cache;
 106         }
 107         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 108                         sizeof(struct t10_alua_lu_gp_member),
 109                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 110         if (!t10_alua_lu_gp_mem_cache) {
 111                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 112                                 "cache failed\n");
 113                 goto out_free_lu_gp_cache;
 114         }
 115         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 116                         sizeof(struct t10_alua_tg_pt_gp),
 117                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 118         if (!t10_alua_tg_pt_gp_cache) {
 119                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 120                                 "cache failed\n");
 121                 goto out_free_lu_gp_mem_cache;
 122         }
 123         t10_alua_tg_pt_gp_mem_cache = kmem_cache_create(
 124                         "t10_alua_tg_pt_gp_mem_cache",
 125                         sizeof(struct t10_alua_tg_pt_gp_member),
 126                         __alignof__(struct t10_alua_tg_pt_gp_member),
 127                         0, NULL);
 128         if (!t10_alua_tg_pt_gp_mem_cache) {
 129                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 130                                 "mem_t failed\n");
 131                 goto out_free_tg_pt_gp_cache;
 132         }
 133         t10_alua_lba_map_cache = kmem_cache_create(
 134                         "t10_alua_lba_map_cache",
 135                         sizeof(struct t10_alua_lba_map),
 136                         __alignof__(struct t10_alua_lba_map), 0, NULL);
 137         if (!t10_alua_lba_map_cache) {
 138                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
 139                                 "cache failed\n");
 140                 goto out_free_tg_pt_gp_mem_cache;
 141         }
 142         t10_alua_lba_map_mem_cache = kmem_cache_create(
 143                         "t10_alua_lba_map_mem_cache",
 144                         sizeof(struct t10_alua_lba_map_member),
 145                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
 146         if (!t10_alua_lba_map_mem_cache) {
 147                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
 148                                 "cache failed\n");
 149                 goto out_free_lba_map_cache;
 150         }
 151
 152         target_completion_wq = alloc_workqueue("target_completion",
 153                                                WQ_MEM_RECLAIM, 0);
 154         if (!target_completion_wq)
 155                 goto out_free_lba_map_mem_cache;
 156
 157         return 0;
 158
 159 out_free_lba_map_mem_cache:
 160         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 161 out_free_lba_map_cache:
 162         kmem_cache_destroy(t10_alua_lba_map_cache);
 163 out_free_tg_pt_gp_mem_cache:
 164         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 165 out_free_tg_pt_gp_cache:
 166         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 167 out_free_lu_gp_mem_cache:
 168         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 169 out_free_lu_gp_cache:
 170         kmem_cache_destroy(t10_alua_lu_gp_cache);
 171 out_free_pr_reg_cache:
 172         kmem_cache_destroy(t10_pr_reg_cache);
 173 out_free_ua_cache:
 174         kmem_cache_destroy(se_ua_cache);
 175 out_free_sess_cache:
 176         kmem_cache_destroy(se_sess_cache);
 177 out:
 178         return -ENOMEM;
 179 }
 180
 181 void release_se_kmem_caches(void)
 182 {
 183         destroy_workqueue(target_completion_wq);
 184         kmem_cache_destroy(se_sess_cache);
 185         kmem_cache_destroy(se_ua_cache);
 186         kmem_cache_destroy(t10_pr_reg_cache);
 187         kmem_cache_destroy(t10_alua_lu_gp_cache);
 188         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 189         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 190         kmem_cache_destroy(t10_alua_tg_pt_gp_mem_cache);
 191         kmem_cache_destroy(t10_alua_lba_map_cache);
 192         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 193 }
 194
 195 /* This code ensures unique mib indexes are handed out. */
 196 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 197 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 198
 199 /*
 200  * Allocate a new row index for the entry type specified
 201  */
 202 u32 scsi_get_new_index(scsi_index_t type)
 203 {
 204         u32 new_index;
 205
 206         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 207
 208         spin_lock(&scsi_mib_index_lock);
 209         new_index = ++scsi_mib_index[type];
 210         spin_unlock(&scsi_mib_index_lock);
 211
 212         return new_index;
 213 }
 214
 215 void transport_subsystem_check_init(void)
 216 {
 217         int ret;
 218         static int sub_api_initialized;
 219
 220         if (sub_api_initialized)
 221                 return;
 222
 223         ret = request_module("target_core_iblock");
 224         if (ret != 0)
 225                 pr_err("Unable to load target_core_iblock\n");
 226
 227         ret = request_module("target_core_file");
 228         if (ret != 0)
 229                 pr_err("Unable to load target_core_file\n");
 230
 231         ret = request_module("target_core_pscsi");
 232         if (ret != 0)
 233                 pr_err("Unable to load target_core_pscsi\n");
 234
 235         ret = request_module("target_core_user");
 236         if (ret != 0)
 237                 pr_err("Unable to load target_core_user\n");
 238
 239         sub_api_initialized = 1;
 240 }
 241
 242 struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
 243 {
 244         struct se_session *se_sess;
 245
 246         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 247         if (!se_sess) {
 248                 pr_err("Unable to allocate struct se_session from"
 249                                 " se_sess_cache\n");
 250                 return ERR_PTR(-ENOMEM);
 251         }
 252         INIT_LIST_HEAD(&se_sess->sess_list);
 253         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 254         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 255         INIT_LIST_HEAD(&se_sess->sess_wait_list);
 256         spin_lock_init(&se_sess->sess_cmd_lock);
 257         kref_init(&se_sess->sess_kref);
 258         se_sess->sup_prot_ops = sup_prot_ops;
 259
 260         return se_sess;
 261 }
 262 EXPORT_SYMBOL(transport_init_session);
 263
 264 int transport_alloc_session_tags(struct se_session *se_sess,
 265                                  unsigned int tag_num, unsigned int tag_size)
 266 {
 267         int rc;
 268
 269         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
 270                                         GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
 271         if (!se_sess->sess_cmd_map) {
 272                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
 273                 if (!se_sess->sess_cmd_map) {
 274                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 275                         return -ENOMEM;
 276                 }
 277         }
 278
 279         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
 280         if (rc < 0) {
 281                 pr_err("Unable to init se_sess->sess_tag_pool,"
 282                         " tag_num: %u\n", tag_num);
 283                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 284                         vfree(se_sess->sess_cmd_map);
 285                 else
 286                         kfree(se_sess->sess_cmd_map);
 287                 se_sess->sess_cmd_map = NULL;
 288                 return -ENOMEM;
 289         }
 290
 291         return 0;
 292 }
 293 EXPORT_SYMBOL(transport_alloc_session_tags);
 294
 295 struct se_session *transport_init_session_tags(unsigned int tag_num,
 296                                                unsigned int tag_size,
 297                                                enum target_prot_op sup_prot_ops)
 298 {
 299         struct se_session *se_sess;
 300         int rc;
 301
 302         se_sess = transport_init_session(sup_prot_ops);
 303         if (IS_ERR(se_sess))
 304                 return se_sess;
 305
 306         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 307         if (rc < 0) {
 308                 transport_free_session(se_sess);
 309                 return ERR_PTR(-ENOMEM);
 310         }
 311
 312         return se_sess;
 313 }
 314 EXPORT_SYMBOL(transport_init_session_tags);
 315
 316 /*
 317  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 318  */
 319 void __transport_register_session(
 320         struct se_portal_group *se_tpg,
 321         struct se_node_acl *se_nacl,
 322         struct se_session *se_sess,
 323         void *fabric_sess_ptr)
 324 {
 325         const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
 326         unsigned char buf[PR_REG_ISID_LEN];
 327
 328         se_sess->se_tpg = se_tpg;
 329         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 330         /*
 331          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 332          *
 333          * Only set for struct se_session's that will actually be moving I/O.
 334          * eg: *NOT* discovery sessions.
 335          */
 336         if (se_nacl) {
 337                 /*
 338                  *
 339                  * Determine if fabric allows for T10-PI feature bits exposed to
 340                  * initiators for device backends with !dev->dev_attrib.pi_prot_type.
 341                  *
 342                  * If so, then always save prot_type on a per se_node_acl node
 343                  * basis and re-instate the previous sess_prot_type to avoid
 344                  * disabling PI from below any previously initiator side
 345                  * registered LUNs.
 346                  */
 347                 if (se_nacl->saved_prot_type)
 348                         se_sess->sess_prot_type = se_nacl->saved_prot_type;
 349                 else if (tfo->tpg_check_prot_fabric_only)
 350                         se_sess->sess_prot_type = se_nacl->saved_prot_type =
 351                                         tfo->tpg_check_prot_fabric_only(se_tpg);
 352                 /*
 353                  * If the fabric module supports an ISID based TransportID,
 354                  * save this value in binary from the fabric I_T Nexus now.
 355                  */
 356                 if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 357                         memset(&buf[0], 0, PR_REG_ISID_LEN);
 358                         se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 359                                         &buf[0], PR_REG_ISID_LEN);
 360                         se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 361                 }
 362                 kref_get(&se_nacl->acl_kref);
 363
 364                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 365                 /*
 366                  * The se_nacl->nacl_sess pointer will be set to the
 367                  * last active I_T Nexus for each struct se_node_acl.
 368                  */
 369                 se_nacl->nacl_sess = se_sess;
 370
 371                 list_add_tail(&se_sess->sess_acl_list,
 372                               &se_nacl->acl_sess_list);
 373                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 374         }
 375         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 376
 377         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 378                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 379 }
 380 EXPORT_SYMBOL(__transport_register_session);
 381
 382 void transport_register_session(
 383         struct se_portal_group *se_tpg,
 384         struct se_node_acl *se_nacl,
 385         struct se_session *se_sess,
 386         void *fabric_sess_ptr)
 387 {
 388         unsigned long flags;
 389
 390         spin_lock_irqsave(&se_tpg->session_lock, flags);
 391         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 392         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 393 }
 394 EXPORT_SYMBOL(transport_register_session);
 395
 396 static void target_release_session(struct kref *kref)
 397 {
 398         struct se_session *se_sess = container_of(kref,
 399                         struct se_session, sess_kref);
 400         struct se_portal_group *se_tpg = se_sess->se_tpg;
 401
 402         se_tpg->se_tpg_tfo->close_session(se_sess);
 403 }
 404
 405 void target_get_session(struct se_session *se_sess)
 406 {
 407         kref_get(&se_sess->sess_kref);
 408 }
 409 EXPORT_SYMBOL(target_get_session);
 410
 411 void target_put_session(struct se_session *se_sess)
 412 {
 413         struct se_portal_group *tpg = se_sess->se_tpg;
 414
 415         if (tpg->se_tpg_tfo->put_session != NULL) {
 416                 tpg->se_tpg_tfo->put_session(se_sess);
 417                 return;
 418         }
 419         kref_put(&se_sess->sess_kref, target_release_session);
 420 }
 421 EXPORT_SYMBOL(target_put_session);
 422
 423 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
 424 {
 425         struct se_session *se_sess;
 426         ssize_t len = 0;
 427
 428         spin_lock_bh(&se_tpg->session_lock);
 429         list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
 430                 if (!se_sess->se_node_acl)
 431                         continue;
 432                 if (!se_sess->se_node_acl->dynamic_node_acl)
 433                         continue;
 434                 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
 435                         break;
 436
 437                 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
 438                                 se_sess->se_node_acl->initiatorname);
 439                 len += 1; /* Include NULL terminator */
 440         }
 441         spin_unlock_bh(&se_tpg->session_lock);
 442
 443         return len;
 444 }
 445 EXPORT_SYMBOL(target_show_dynamic_sessions);
 446
 447 static void target_complete_nacl(struct kref *kref)
 448 {
 449         struct se_node_acl *nacl = container_of(kref,
 450                                 struct se_node_acl, acl_kref);
 451
 452         complete(&nacl->acl_free_comp);
 453 }
 454
 455 void target_put_nacl(struct se_node_acl *nacl)
 456 {
 457         kref_put(&nacl->acl_kref, target_complete_nacl);
 458 }
 459
 460 void transport_deregister_session_configfs(struct se_session *se_sess)
 461 {
 462         struct se_node_acl *se_nacl;
 463         unsigned long flags;
 464         /*
 465          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 466          */
 467         se_nacl = se_sess->se_node_acl;
 468         if (se_nacl) {
 469                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 470                 if (se_nacl->acl_stop == 0)
 471                         list_del(&se_sess->sess_acl_list);
 472                 /*
 473                  * If the session list is empty, then clear the pointer.
 474                  * Otherwise, set the struct se_session pointer from the tail
 475                  * element of the per struct se_node_acl active session list.
 476                  */
 477                 if (list_empty(&se_nacl->acl_sess_list))
 478                         se_nacl->nacl_sess = NULL;
 479                 else {
 480                         se_nacl->nacl_sess = container_of(
 481                                         se_nacl->acl_sess_list.prev,
 482                                         struct se_session, sess_acl_list);
 483                 }
 484                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 485         }
 486 }
 487 EXPORT_SYMBOL(transport_deregister_session_configfs);
 488
 489 void transport_free_session(struct se_session *se_sess)
 490 {
 491         if (se_sess->sess_cmd_map) {
 492                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 493                 if (is_vmalloc_addr(se_sess->sess_cmd_map))
 494                         vfree(se_sess->sess_cmd_map);
 495                 else
 496                         kfree(se_sess->sess_cmd_map);
 497         }
 498         kmem_cache_free(se_sess_cache, se_sess);
 499 }
 500 EXPORT_SYMBOL(transport_free_session);
 501
 502 void transport_deregister_session(struct se_session *se_sess)
 503 {
 504         struct se_portal_group *se_tpg = se_sess->se_tpg;
 505         const struct target_core_fabric_ops *se_tfo;
 506         struct se_node_acl *se_nacl;
 507         unsigned long flags;
 508         bool comp_nacl = true;
 509
 510         if (!se_tpg) {
 511                 transport_free_session(se_sess);
 512                 return;
 513         }
 514         se_tfo = se_tpg->se_tpg_tfo;
 515
 516         spin_lock_irqsave(&se_tpg->session_lock, flags);
 517         list_del(&se_sess->sess_list);
 518         se_sess->se_tpg = NULL;
 519         se_sess->fabric_sess_ptr = NULL;
 520         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 521
 522         /*
 523          * Determine if we need to do extra work for this initiator node's
 524          * struct se_node_acl if it had been previously dynamically generated.
 525          */
 526         se_nacl = se_sess->se_node_acl;
 527
 528         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 529         if (se_nacl && se_nacl->dynamic_node_acl) {
 530                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 531                         list_del(&se_nacl->acl_list);
 532                         se_tpg->num_node_acls--;
 533                         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 534                         core_tpg_wait_for_nacl_pr_ref(se_nacl);
 535                         core_free_device_list_for_node(se_nacl, se_tpg);
 536                         kfree(se_nacl);
 537
 538                         comp_nacl = false;
 539                         spin_lock_irqsave(&se_tpg->acl_node_lock, flags);
 540                 }
 541         }
 542         spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags);
 543
 544         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 545                 se_tpg->se_tpg_tfo->get_fabric_name());
 546         /*
 547          * If last kref is dropping now for an explicit NodeACL, awake sleeping
 548          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 549          * removal context.
 550          */
 551         if (se_nacl && comp_nacl)
 552                 target_put_nacl(se_nacl);
 553
 554         transport_free_session(se_sess);
 555 }
 556 EXPORT_SYMBOL(transport_deregister_session);
 557
 558 /*
 559  * Called with cmd->t_state_lock held.
 560  */
 561 static void target_remove_from_state_list(struct se_cmd *cmd)
 562 {
 563         struct se_device *dev = cmd->se_dev;
 564         unsigned long flags;
 565
 566         if (!dev)
 567                 return;
 568
 569         if (cmd->transport_state & CMD_T_BUSY)
 570                 return;
 571
 572         spin_lock_irqsave(&dev->execute_task_lock, flags);
 573         if (cmd->state_active) {
 574                 list_del(&cmd->state_list);
 575                 cmd->state_active = false;
 576         }
 577         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 578 }
 579
 580 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 581                                     bool write_pending)
 582 {
 583         unsigned long flags;
 584
 585         spin_lock_irqsave(&cmd->t_state_lock, flags);
 586         if (write_pending)
 587                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 588
 589         if (remove_from_lists) {
 590                 target_remove_from_state_list(cmd);
 591
 592                 /*
 593                  * Clear struct se_cmd->se_lun before the handoff to FE.
 594                  */
 595                 cmd->se_lun = NULL;
 596         }
 597
 598         /*
 599          * Determine if frontend context caller is requesting the stopping of
 600          * this command for frontend exceptions.
 601          */
 602         if (cmd->transport_state & CMD_T_STOP) {
 603                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
 604                         __func__, __LINE__,
 605                         cmd->se_tfo->get_task_tag(cmd));
 606
 607                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 608
 609                 complete_all(&cmd->t_transport_stop_comp);
 610                 return 1;
 611         }
 612
 613         cmd->transport_state &= ~CMD_T_ACTIVE;
 614         if (remove_from_lists) {
 615                 /*
 616                  * Some fabric modules like tcm_loop can release
 617                  * their internally allocated I/O reference now and
 618                  * struct se_cmd now.
 619                  *
 620                  * Fabric modules are expected to return '1' here if the
 621                  * se_cmd being passed is released at this point,
 622                  * or zero if not being released.
 623                  */
 624                 if (cmd->se_tfo->check_stop_free != NULL) {
 625                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 626                         return cmd->se_tfo->check_stop_free(cmd);
 627                 }
 628         }
 629
 630         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 631         return 0;
 632 }
 633
 634 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 635 {
 636         return transport_cmd_check_stop(cmd, true, false);
 637 }
 638
 639 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 640 {
 641         struct se_lun *lun = cmd->se_lun;
 642
 643         if (!lun)
 644                 return;
 645
 646         if (cmpxchg(&cmd->lun_ref_active, true, false))
 647                 percpu_ref_put(&lun->lun_ref);
 648 }
 649
 650 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 651 {
 652         if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
 653                 transport_lun_remove_cmd(cmd);
 654         /*
 655          * Allow the fabric driver to unmap any resources before
 656          * releasing the descriptor via TFO->release_cmd()
 657          */
 658         if (remove)
 659                 cmd->se_tfo->aborted_task(cmd);
 660
 661         if (transport_cmd_check_stop_to_fabric(cmd))
 662                 return;
 663         if (remove)
 664                 transport_put_cmd(cmd);
 665 }
 666
 667 static void target_complete_failure_work(struct work_struct *work)
 668 {
 669         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 670
 671         transport_generic_request_failure(cmd,
 672                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 673 }
 674
 675 /*
 676  * Used when asking transport to copy Sense Data from the underlying
 677  * Linux/SCSI struct scsi_cmnd
 678  */
 679 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 680 {
 681         struct se_device *dev = cmd->se_dev;
 682
 683         WARN_ON(!cmd->se_lun);
 684
 685         if (!dev)
 686                 return NULL;
 687
 688         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 689                 return NULL;
 690
 691         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 692
 693         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 694                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 695         return cmd->sense_buffer;
 696 }
 697
 698 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 699 {
 700         struct se_device *dev = cmd->se_dev;
 701         int success = scsi_status == GOOD;
 702         unsigned long flags;
 703
 704         cmd->scsi_status = scsi_status;
 705
 706
 707         spin_lock_irqsave(&cmd->t_state_lock, flags);
 708         cmd->transport_state &= ~CMD_T_BUSY;
 709
 710         if (dev && dev->transport->transport_complete) {
 711                 dev->transport->transport_complete(cmd,
 712                                 cmd->t_data_sg,
 713                                 transport_get_sense_buffer(cmd));
 714                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 715                         success = 1;
 716         }
 717
 718         /*
 719          * See if we are waiting to complete for an exception condition.
 720          */
 721         if (cmd->transport_state & CMD_T_REQUEST_STOP) {
 722                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 723                 complete(&cmd->task_stop_comp);
 724                 return;
 725         }
 726
 727         /*
 728          * Check for case where an explicit ABORT_TASK has been received
 729          * and transport_wait_for_tasks() will be waiting for completion..
 730          */
 731         if (cmd->transport_state & CMD_T_ABORTED &&
 732             cmd->transport_state & CMD_T_STOP) {
 733                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 734                 complete_all(&cmd->t_transport_stop_comp);
 735                 return;
 736         } else if (!success) {
 737                 INIT_WORK(&cmd->work, target_complete_failure_work);
 738         } else {
 739                 INIT_WORK(&cmd->work, target_complete_ok_work);
 740         }
 741
 742         cmd->t_state = TRANSPORT_COMPLETE;
 743         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 744         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 745
 746         queue_work(target_completion_wq, &cmd->work);
 747 }
 748 EXPORT_SYMBOL(target_complete_cmd);
 749
 750 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 751 {
 752         if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
 753                 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 754                         cmd->residual_count += cmd->data_length - length;
 755                 } else {
 756                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
 757                         cmd->residual_count = cmd->data_length - length;
 758                 }
 759
 760                 cmd->data_length = length;
 761         }
 762
 763         target_complete_cmd(cmd, scsi_status);
 764 }
 765 EXPORT_SYMBOL(target_complete_cmd_with_length);
 766
 767 static void target_add_to_state_list(struct se_cmd *cmd)
 768 {
 769         struct se_device *dev = cmd->se_dev;
 770         unsigned long flags;
 771
 772         spin_lock_irqsave(&dev->execute_task_lock, flags);
 773         if (!cmd->state_active) {
 774                 list_add_tail(&cmd->state_list, &dev->state_list);
 775                 cmd->state_active = true;
 776         }
 777         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 778 }
 779
 780 /*
 781  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 782  */
 783 static void transport_write_pending_qf(struct se_cmd *cmd);
 784 static void transport_complete_qf(struct se_cmd *cmd);
 785
 786 void target_qf_do_work(struct work_struct *work)
 787 {
 788         struct se_device *dev = container_of(work, struct se_device,
 789                                         qf_work_queue);
 790         LIST_HEAD(qf_cmd_list);
 791         struct se_cmd *cmd, *cmd_tmp;
 792
 793         spin_lock_irq(&dev->qf_cmd_lock);
 794         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 795         spin_unlock_irq(&dev->qf_cmd_lock);
 796
 797         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 798                 list_del(&cmd->se_qf_node);
 799                 atomic_dec_mb(&dev->dev_qf_count);
 800
 801                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 802                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 803                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 804                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 805                         : "UNKNOWN");
 806
 807                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 808                         transport_write_pending_qf(cmd);
 809                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 810                         transport_complete_qf(cmd);
 811         }
 812 }
 813
 814 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 815 {
 816         switch (cmd->data_direction) {
 817         case DMA_NONE:
 818                 return "NONE";
 819         case DMA_FROM_DEVICE:
 820                 return "READ";
 821         case DMA_TO_DEVICE:
 822                 return "WRITE";
 823         case DMA_BIDIRECTIONAL:
 824                 return "BIDI";
 825         default:
 826                 break;
 827         }
 828
 829         return "UNKNOWN";
 830 }
 831
 832 void transport_dump_dev_state(
 833         struct se_device *dev,
 834         char *b,
 835         int *bl)
 836 {
 837         *bl += sprintf(b + *bl, "Status: ");
 838         if (dev->export_count)
 839                 *bl += sprintf(b + *bl, "ACTIVATED");
 840         else
 841                 *bl += sprintf(b + *bl, "DEACTIVATED");
 842
 843         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 844         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 845                 dev->dev_attrib.block_size,
 846                 dev->dev_attrib.hw_max_sectors);
 847         *bl += sprintf(b + *bl, "        ");
 848 }
 849
 850 void transport_dump_vpd_proto_id(
 851         struct t10_vpd *vpd,
 852         unsigned char *p_buf,
 853         int p_buf_len)
 854 {
 855         unsigned char buf[VPD_TMP_BUF_SIZE];
 856         int len;
 857
 858         memset(buf, 0, VPD_TMP_BUF_SIZE);
 859         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 860
 861         switch (vpd->protocol_identifier) {
 862         case 0x00:
 863                 sprintf(buf+len, "Fibre Channel\n");
 864                 break;
 865         case 0x10:
 866                 sprintf(buf+len, "Parallel SCSI\n");
 867                 break;
 868         case 0x20:
 869                 sprintf(buf+len, "SSA\n");
 870                 break;
 871         case 0x30:
 872                 sprintf(buf+len, "IEEE 1394\n");
 873                 break;
 874         case 0x40:
 875                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 876                                 " Protocol\n");
 877                 break;
 878         case 0x50:
 879                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 880                 break;
 881         case 0x60:
 882                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 883                 break;
 884         case 0x70:
 885                 sprintf(buf+len, "Automation/Drive Interface Transport"
 886                                 " Protocol\n");
 887                 break;
 888         case 0x80:
 889                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 890                 break;
 891         default:
 892                 sprintf(buf+len, "Unknown 0x%02x\n",
 893                                 vpd->protocol_identifier);
 894                 break;
 895         }
 896
 897         if (p_buf)
 898                 strncpy(p_buf, buf, p_buf_len);
 899         else
 900                 pr_debug("%s", buf);
 901 }
 902
 903 void
 904 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 905 {
 906         /*
 907          * Check if the Protocol Identifier Valid (PIV) bit is set..
 908          *
 909          * from spc3r23.pdf section 7.5.1
 910          */
 911          if (page_83[1] & 0x80) {
 912                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 913                 vpd->protocol_identifier_set = 1;
 914                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 915         }
 916 }
 917 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 918
 919 int transport_dump_vpd_assoc(
 920         struct t10_vpd *vpd,
 921         unsigned char *p_buf,
 922         int p_buf_len)
 923 {
 924         unsigned char buf[VPD_TMP_BUF_SIZE];
 925         int ret = 0;
 926         int len;
 927
 928         memset(buf, 0, VPD_TMP_BUF_SIZE);
 929         len = sprintf(buf, "T10 VPD Identifier Association: ");
 930
 931         switch (vpd->association) {
 932         case 0x00:
 933                 sprintf(buf+len, "addressed logical unit\n");
 934                 break;
 935         case 0x10:
 936                 sprintf(buf+len, "target port\n");
 937                 break;
 938         case 0x20:
 939                 sprintf(buf+len, "SCSI target device\n");
 940                 break;
 941         default:
 942                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 943                 ret = -EINVAL;
 944                 break;
 945         }
 946
 947         if (p_buf)
 948                 strncpy(p_buf, buf, p_buf_len);
 949         else
 950                 pr_debug("%s", buf);
 951
 952         return ret;
 953 }
 954
 955 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 956 {
 957         /*
 958          * The VPD identification association..
 959          *
 960          * from spc3r23.pdf Section 7.6.3.1 Table 297
 961          */
 962         vpd->association = (page_83[1] & 0x30);
 963         return transport_dump_vpd_assoc(vpd, NULL, 0);
 964 }
 965 EXPORT_SYMBOL(transport_set_vpd_assoc);
 966
 967 int transport_dump_vpd_ident_type(
 968         struct t10_vpd *vpd,
 969         unsigned char *p_buf,
 970         int p_buf_len)
 971 {
 972         unsigned char buf[VPD_TMP_BUF_SIZE];
 973         int ret = 0;
 974         int len;
 975
 976         memset(buf, 0, VPD_TMP_BUF_SIZE);
 977         len = sprintf(buf, "T10 VPD Identifier Type: ");
 978
 979         switch (vpd->device_identifier_type) {
 980         case 0x00:
 981                 sprintf(buf+len, "Vendor specific\n");
 982                 break;
 983         case 0x01:
 984                 sprintf(buf+len, "T10 Vendor ID based\n");
 985                 break;
 986         case 0x02:
 987                 sprintf(buf+len, "EUI-64 based\n");
 988                 break;
 989         case 0x03:
 990                 sprintf(buf+len, "NAA\n");
 991                 break;
 992         case 0x04:
 993                 sprintf(buf+len, "Relative target port identifier\n");
 994                 break;
 995         case 0x08:
 996                 sprintf(buf+len, "SCSI name string\n");
 997                 break;
 998         default:
 999                 sprintf(buf+len, "Unsupported: 0x%02x\n",
1000                                 vpd->device_identifier_type);
1001                 ret = -EINVAL;
1002                 break;
1003         }
1004
1005         if (p_buf) {
1006                 if (p_buf_len < strlen(buf)+1)
1007                         return -EINVAL;
1008                 strncpy(p_buf, buf, p_buf_len);
1009         } else {
1010                 pr_debug("%s", buf);
1011         }
1012
1013         return ret;
1014 }
1015
1016 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1017 {
1018         /*
1019          * The VPD identifier type..
1020          *
1021          * from spc3r23.pdf Section 7.6.3.1 Table 298
1022          */
1023         vpd->device_identifier_type = (page_83[1] & 0x0f);
1024         return transport_dump_vpd_ident_type(vpd, NULL, 0);
1025 }
1026 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1027
1028 int transport_dump_vpd_ident(
1029         struct t10_vpd *vpd,
1030         unsigned char *p_buf,
1031         int p_buf_len)
1032 {
1033         unsigned char buf[VPD_TMP_BUF_SIZE];
1034         int ret = 0;
1035
1036         memset(buf, 0, VPD_TMP_BUF_SIZE);
1037
1038         switch (vpd->device_identifier_code_set) {
1039         case 0x01: /* Binary */
1040                 snprintf(buf, sizeof(buf),
1041                         "T10 VPD Binary Device Identifier: %s\n",
1042                         &vpd->device_identifier[0]);
1043                 break;
1044         case 0x02: /* ASCII */
1045                 snprintf(buf, sizeof(buf),
1046                         "T10 VPD ASCII Device Identifier: %s\n",
1047                         &vpd->device_identifier[0]);
1048                 break;
1049         case 0x03: /* UTF-8 */
1050                 snprintf(buf, sizeof(buf),
1051                         "T10 VPD UTF-8 Device Identifier: %s\n",
1052                         &vpd->device_identifier[0]);
1053                 break;
1054         default:
1055                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1056                         " 0x%02x", vpd->device_identifier_code_set);
1057                 ret = -EINVAL;
1058                 break;
1059         }
1060
1061         if (p_buf)
1062                 strncpy(p_buf, buf, p_buf_len);
1063         else
1064                 pr_debug("%s", buf);
1065
1066         return ret;
1067 }
1068
1069 int
1070 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1071 {
1072         static const char hex_str[] = "0123456789abcdef";
1073         int j = 0, i = 4; /* offset to start of the identifier */
1074
1075         /*
1076          * The VPD Code Set (encoding)
1077          *
1078          * from spc3r23.pdf Section 7.6.3.1 Table 296
1079          */
1080         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1081         switch (vpd->device_identifier_code_set) {
1082         case 0x01: /* Binary */
1083                 vpd->device_identifier[j++] =
1084                                 hex_str[vpd->device_identifier_type];
1085                 while (i < (4 + page_83[3])) {
1086                         vpd->device_identifier[j++] =
1087                                 hex_str[(page_83[i] & 0xf0) >> 4];
1088                         vpd->device_identifier[j++] =
1089                                 hex_str[page_83[i] & 0x0f];
1090                         i++;
1091                 }
1092                 break;
1093         case 0x02: /* ASCII */
1094         case 0x03: /* UTF-8 */
1095                 while (i < (4 + page_83[3]))
1096                         vpd->device_identifier[j++] = page_83[i++];
1097                 break;
1098         default:
1099                 break;
1100         }
1101
1102         return transport_dump_vpd_ident(vpd, NULL, 0);
1103 }
1104 EXPORT_SYMBOL(transport_set_vpd_ident);
1105
1106 sense_reason_t
1107 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1108 {
1109         struct se_device *dev = cmd->se_dev;
1110
1111         if (cmd->unknown_data_length) {
1112                 cmd->data_length = size;
1113         } else if (size != cmd->data_length) {
1114                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1115                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1116                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1117                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1118
1119                 if (cmd->data_direction == DMA_TO_DEVICE) {
1120                         pr_err("Rejecting underflow/overflow"
1121                                         " WRITE data\n");
1122                         return TCM_INVALID_CDB_FIELD;
1123                 }
1124                 /*
1125                  * Reject READ_* or WRITE_* with overflow/underflow for
1126                  * type SCF_SCSI_DATA_CDB.
1127                  */
1128                 if (dev->dev_attrib.block_size != 512)  {
1129                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1130                                 " CDB on non 512-byte sector setup subsystem"
1131                                 " plugin: %s\n", dev->transport->name);
1132                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1133                         return TCM_INVALID_CDB_FIELD;
1134                 }
1135                 /*
1136                  * For the overflow case keep the existing fabric provided
1137                  * ->data_length.  Otherwise for the underflow case, reset
1138                  * ->data_length to the smaller SCSI expected data transfer
1139                  * length.
1140                  */
1141                 if (size > cmd->data_length) {
1142                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1143                         cmd->residual_count = (size - cmd->data_length);
1144                 } else {
1145                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1146                         cmd->residual_count = (cmd->data_length - size);
1147                         cmd->data_length = size;
1148                 }
1149         }
1150
1151         return 0;
1152
1153 }
1154
1155 /*
1156  * Used by fabric modules containing a local struct se_cmd within their
1157  * fabric dependent per I/O descriptor.
1158  */
1159 void transport_init_se_cmd(
1160         struct se_cmd *cmd,
1161         const struct target_core_fabric_ops *tfo,
1162         struct se_session *se_sess,
1163         u32 data_length,
1164         int data_direction,
1165         int task_attr,
1166         unsigned char *sense_buffer)
1167 {
1168         INIT_LIST_HEAD(&cmd->se_delayed_node);
1169         INIT_LIST_HEAD(&cmd->se_qf_node);
1170         INIT_LIST_HEAD(&cmd->se_cmd_list);
1171         INIT_LIST_HEAD(&cmd->state_list);
1172         init_completion(&cmd->t_transport_stop_comp);
1173         init_completion(&cmd->cmd_wait_comp);
1174         init_completion(&cmd->task_stop_comp);
1175         spin_lock_init(&cmd->t_state_lock);
1176         kref_init(&cmd->cmd_kref);
1177         cmd->transport_state = CMD_T_DEV_ACTIVE;
1178
1179         cmd->se_tfo = tfo;
1180         cmd->se_sess = se_sess;
1181         cmd->data_length = data_length;
1182         cmd->data_direction = data_direction;
1183         cmd->sam_task_attr = task_attr;
1184         cmd->sense_buffer = sense_buffer;
1185
1186         cmd->state_active = false;
1187 }
1188 EXPORT_SYMBOL(transport_init_se_cmd);
1189
1190 static sense_reason_t
1191 transport_check_alloc_task_attr(struct se_cmd *cmd)
1192 {
1193         struct se_device *dev = cmd->se_dev;
1194
1195         /*
1196          * Check if SAM Task Attribute emulation is enabled for this
1197          * struct se_device storage object
1198          */
1199         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1200                 return 0;
1201
1202         if (cmd->sam_task_attr == TCM_ACA_TAG) {
1203                 pr_debug("SAM Task Attribute ACA"
1204                         " emulation is not supported\n");
1205                 return TCM_INVALID_CDB_FIELD;
1206         }
1207         /*
1208          * Used to determine when ORDERED commands should go from
1209          * Dormant to Active status.
1210          */
1211         cmd->se_ordered_id = atomic_inc_return(&dev->dev_ordered_id);
1212         pr_debug("Allocated se_ordered_id: %u for Task Attr: 0x%02x on %s\n",
1213                         cmd->se_ordered_id, cmd->sam_task_attr,
1214                         dev->transport->name);
1215         return 0;
1216 }
1217
1218 sense_reason_t
1219 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1220 {
1221         struct se_device *dev = cmd->se_dev;
1222         sense_reason_t ret;
1223
1224         /*
1225          * Ensure that the received CDB is less than the max (252 + 8) bytes
1226          * for VARIABLE_LENGTH_CMD
1227          */
1228         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1229                 pr_err("Received SCSI CDB with command_size: %d that"
1230                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1231                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1232                 return TCM_INVALID_CDB_FIELD;
1233         }
1234         /*
1235          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1236          * allocate the additional extended CDB buffer now..  Otherwise
1237          * setup the pointer from __t_task_cdb to t_task_cdb.
1238          */
1239         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1240                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1241                                                 GFP_KERNEL);
1242                 if (!cmd->t_task_cdb) {
1243                         pr_err("Unable to allocate cmd->t_task_cdb"
1244                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1245                                 scsi_command_size(cdb),
1246                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1247                         return TCM_OUT_OF_RESOURCES;
1248                 }
1249         } else
1250                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1251         /*
1252          * Copy the original CDB into cmd->
1253          */
1254         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1255
1256         trace_target_sequencer_start(cmd);
1257
1258         /*
1259          * Check for an existing UNIT ATTENTION condition
1260          */
1261         ret = target_scsi3_ua_check(cmd);
1262         if (ret)
1263                 return ret;
1264
1265         ret = target_alua_state_check(cmd);
1266         if (ret)
1267                 return ret;
1268
1269         ret = target_check_reservation(cmd);
1270         if (ret) {
1271                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1272                 return ret;
1273         }
1274
1275         ret = dev->transport->parse_cdb(cmd);
1276         if (ret)
1277                 return ret;
1278
1279         ret = transport_check_alloc_task_attr(cmd);
1280         if (ret)
1281                 return ret;
1282
1283         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1284
1285         spin_lock(&cmd->se_lun->lun_sep_lock);
1286         if (cmd->se_lun->lun_sep)
1287                 cmd->se_lun->lun_sep->sep_stats.cmd_pdus++;
1288         spin_unlock(&cmd->se_lun->lun_sep_lock);
1289         return 0;
1290 }
1291 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1292
1293 /*
1294  * Used by fabric module frontends to queue tasks directly.
1295  * Many only be used from process context only
1296  */
1297 int transport_handle_cdb_direct(
1298         struct se_cmd *cmd)
1299 {
1300         sense_reason_t ret;
1301
1302         if (!cmd->se_lun) {
1303                 dump_stack();
1304                 pr_err("cmd->se_lun is NULL\n");
1305                 return -EINVAL;
1306         }
1307         if (in_interrupt()) {
1308                 dump_stack();
1309                 pr_err("transport_generic_handle_cdb cannot be called"
1310                                 " from interrupt context\n");
1311                 return -EINVAL;
1312         }
1313         /*
1314          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1315          * outstanding descriptors are handled correctly during shutdown via
1316          * transport_wait_for_tasks()
1317          *
1318          * Also, we don't take cmd->t_state_lock here as we only expect
1319          * this to be called for initial descriptor submission.
1320          */
1321         cmd->t_state = TRANSPORT_NEW_CMD;
1322         cmd->transport_state |= CMD_T_ACTIVE;
1323
1324         /*
1325          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1326          * so follow TRANSPORT_NEW_CMD processing thread context usage
1327          * and call transport_generic_request_failure() if necessary..
1328          */
1329         ret = transport_generic_new_cmd(cmd);
1330         if (ret)
1331                 transport_generic_request_failure(cmd, ret);
1332         return 0;
1333 }
1334 EXPORT_SYMBOL(transport_handle_cdb_direct);
1335
1336 sense_reason_t
1337 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1338                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1339 {
1340         if (!sgl || !sgl_count)
1341                 return 0;
1342
1343         /*
1344          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1345          * scatterlists already have been set to follow what the fabric
1346          * passes for the original expected data transfer length.
1347          */
1348         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1349                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1350                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1351                 return TCM_INVALID_CDB_FIELD;
1352         }
1353
1354         cmd->t_data_sg = sgl;
1355         cmd->t_data_nents = sgl_count;
1356         cmd->t_bidi_data_sg = sgl_bidi;
1357         cmd->t_bidi_data_nents = sgl_bidi_count;
1358
1359         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1360         return 0;
1361 }
1362
1363 /*
1364  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1365  *                       se_cmd + use pre-allocated SGL memory.
1366  *
1367  * @se_cmd: command descriptor to submit
1368  * @se_sess: associated se_sess for endpoint
1369  * @cdb: pointer to SCSI CDB
1370  * @sense: pointer to SCSI sense buffer
1371  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1372  * @data_length: fabric expected data transfer length
1373  * @task_addr: SAM task attribute
1374  * @data_dir: DMA data direction
1375  * @flags: flags for command submission from target_sc_flags_tables
1376  * @sgl: struct scatterlist memory for unidirectional mapping
1377  * @sgl_count: scatterlist count for unidirectional mapping
1378  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1379  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1380  * @sgl_prot: struct scatterlist memory protection information
1381  * @sgl_prot_count: scatterlist count for protection information
1382  *
1383  * Returns non zero to signal active I/O shutdown failure.  All other
1384  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1385  * but still return zero here.
1386  *
1387  * This may only be called from process context, and also currently
1388  * assumes internal allocation of fabric payload buffer by target-core.
1389  */
1390 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1391                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1392                 u32 data_length, int task_attr, int data_dir, int flags,
1393                 struct scatterlist *sgl, u32 sgl_count,
1394                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1395                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1396 {
1397         struct se_portal_group *se_tpg;
1398         sense_reason_t rc;
1399         int ret;
1400
1401         se_tpg = se_sess->se_tpg;
1402         BUG_ON(!se_tpg);
1403         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1404         BUG_ON(in_interrupt());
1405         /*
1406          * Initialize se_cmd for target operation.  From this point
1407          * exceptions are handled by sending exception status via
1408          * target_core_fabric_ops->queue_status() callback
1409          */
1410         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1411                                 data_length, data_dir, task_attr, sense);
1412         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1413                 se_cmd->unknown_data_length = 1;
1414         /*
1415          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1416          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1417          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1418          * kref_put() to happen during fabric packet acknowledgement.
1419          */
1420         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1421         if (ret)
1422                 return ret;
1423         /*
1424          * Signal bidirectional data payloads to target-core
1425          */
1426         if (flags & TARGET_SCF_BIDI_OP)
1427                 se_cmd->se_cmd_flags |= SCF_BIDI;
1428         /*
1429          * Locate se_lun pointer and attach it to struct se_cmd
1430          */
1431         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1432         if (rc) {
1433                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1434                 target_put_sess_cmd(se_cmd);
1435                 return 0;
1436         }
1437
1438         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1439         if (rc != 0) {
1440                 transport_generic_request_failure(se_cmd, rc);
1441                 return 0;
1442         }
1443
1444         /*
1445          * Save pointers for SGLs containing protection information,
1446          * if present.
1447          */
1448         if (sgl_prot_count) {
1449                 se_cmd->t_prot_sg = sgl_prot;
1450                 se_cmd->t_prot_nents = sgl_prot_count;
1451         }
1452
1453         /*
1454          * When a non zero sgl_count has been passed perform SGL passthrough
1455          * mapping for pre-allocated fabric memory instead of having target
1456          * core perform an internal SGL allocation..
1457          */
1458         if (sgl_count != 0) {
1459                 BUG_ON(!sgl);
1460
1461                 /*
1462                  * A work-around for tcm_loop as some userspace code via
1463                  * scsi-generic do not memset their associated read buffers,
1464                  * so go ahead and do that here for type non-data CDBs.  Also
1465                  * note that this is currently guaranteed to be a single SGL
1466                  * for this case by target core in target_setup_cmd_from_cdb()
1467                  * -> transport_generic_cmd_sequencer().
1468                  */
1469                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1470                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1471                         unsigned char *buf = NULL;
1472
1473                         if (sgl)
1474                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1475
1476                         if (buf) {
1477                                 memset(buf, 0, sgl->length);
1478                                 kunmap(sg_page(sgl));
1479                         }
1480                 }
1481
1482                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1483                                 sgl_bidi, sgl_bidi_count);
1484                 if (rc != 0) {
1485                         transport_generic_request_failure(se_cmd, rc);
1486                         return 0;
1487                 }
1488         }
1489
1490         /*
1491          * Check if we need to delay processing because of ALUA
1492          * Active/NonOptimized primary access state..
1493          */
1494         core_alua_check_nonop_delay(se_cmd);
1495
1496         transport_handle_cdb_direct(se_cmd);
1497         return 0;
1498 }
1499 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1500
1501 /*
1502  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1503  *
1504  * @se_cmd: command descriptor to submit
1505  * @se_sess: associated se_sess for endpoint
1506  * @cdb: pointer to SCSI CDB
1507  * @sense: pointer to SCSI sense buffer
1508  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1509  * @data_length: fabric expected data transfer length
1510  * @task_addr: SAM task attribute
1511  * @data_dir: DMA data direction
1512  * @flags: flags for command submission from target_sc_flags_tables
1513  *
1514  * Returns non zero to signal active I/O shutdown failure.  All other
1515  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1516  * but still return zero here.
1517  *
1518  * This may only be called from process context, and also currently
1519  * assumes internal allocation of fabric payload buffer by target-core.
1520  *
1521  * It also assumes interal target core SGL memory allocation.
1522  */
1523 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1524                 unsigned char *cdb, unsigned char *sense, u32 unpacked_lun,
1525                 u32 data_length, int task_attr, int data_dir, int flags)
1526 {
1527         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1528                         unpacked_lun, data_length, task_attr, data_dir,
1529                         flags, NULL, 0, NULL, 0, NULL, 0);
1530 }
1531 EXPORT_SYMBOL(target_submit_cmd);
1532
1533 static void target_complete_tmr_failure(struct work_struct *work)
1534 {
1535         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1536
1537         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1538         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1539
1540         transport_cmd_check_stop_to_fabric(se_cmd);
1541 }
1542
1543 /**
1544  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1545  *                     for TMR CDBs
1546  *
1547  * @se_cmd: command descriptor to submit
1548  * @se_sess: associated se_sess for endpoint
1549  * @sense: pointer to SCSI sense buffer
1550  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1551  * @fabric_context: fabric context for TMR req
1552  * @tm_type: Type of TM request
1553  * @gfp: gfp type for caller
1554  * @tag: referenced task tag for TMR_ABORT_TASK
1555  * @flags: submit cmd flags
1556  *
1557  * Callable from all contexts.
1558  **/
1559
1560 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1561                 unsigned char *sense, u32 unpacked_lun,
1562                 void *fabric_tmr_ptr, unsigned char tm_type,
1563                 gfp_t gfp, unsigned int tag, int flags)
1564 {
1565         struct se_portal_group *se_tpg;
1566         int ret;
1567
1568         se_tpg = se_sess->se_tpg;
1569         BUG_ON(!se_tpg);
1570
1571         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1572                               0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1573         /*
1574          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1575          * allocation failure.
1576          */
1577         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1578         if (ret < 0)
1579                 return -ENOMEM;
1580
1581         if (tm_type == TMR_ABORT_TASK)
1582                 se_cmd->se_tmr_req->ref_task_tag = tag;
1583
1584         /* See target_submit_cmd for commentary */
1585         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1586         if (ret) {
1587                 core_tmr_release_req(se_cmd->se_tmr_req);
1588                 return ret;
1589         }
1590
1591         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1592         if (ret) {
1593                 /*
1594                  * For callback during failure handling, push this work off
1595                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1596                  */
1597                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1598                 schedule_work(&se_cmd->work);
1599                 return 0;
1600         }
1601         transport_generic_handle_tmr(se_cmd);
1602         return 0;
1603 }
1604 EXPORT_SYMBOL(target_submit_tmr);
1605
1606 /*
1607  * If the cmd is active, request it to be stopped and sleep until it
1608  * has completed.
1609  */
1610 bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags)
1611         __releases(&cmd->t_state_lock)
1612         __acquires(&cmd->t_state_lock)
1613 {
1614         bool was_active = false;
1615
1616         if (cmd->transport_state & CMD_T_BUSY) {
1617                 cmd->transport_state |= CMD_T_REQUEST_STOP;
1618                 spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
1619
1620                 pr_debug("cmd %p waiting to complete\n", cmd);
1621                 wait_for_completion(&cmd->task_stop_comp);
1622                 pr_debug("cmd %p stopped successfully\n", cmd);
1623
1624                 spin_lock_irqsave(&cmd->t_state_lock, *flags);
1625                 cmd->transport_state &= ~CMD_T_REQUEST_STOP;
1626                 cmd->transport_state &= ~CMD_T_BUSY;
1627                 was_active = true;
1628         }
1629
1630         return was_active;
1631 }
1632
1633 /*
1634  * Handle SAM-esque emulation for generic transport request failures.
1635  */
1636 void transport_generic_request_failure(struct se_cmd *cmd,
1637                 sense_reason_t sense_reason)
1638 {
1639         int ret = 0;
1640
1641         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x"
1642                 " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd),
1643                 cmd->t_task_cdb[0]);
1644         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1645                 cmd->se_tfo->get_cmd_state(cmd),
1646                 cmd->t_state, sense_reason);
1647         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1648                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1649                 (cmd->transport_state & CMD_T_STOP) != 0,
1650                 (cmd->transport_state & CMD_T_SENT) != 0);
1651
1652         /*
1653          * For SAM Task Attribute emulation for failed struct se_cmd
1654          */
1655         transport_complete_task_attr(cmd);
1656         /*
1657          * Handle special case for COMPARE_AND_WRITE failure, where the
1658          * callback is expected to drop the per device ->caw_sem.
1659          */
1660         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1661              cmd->transport_complete_callback)
1662                 cmd->transport_complete_callback(cmd, false);
1663
1664         switch (sense_reason) {
1665         case TCM_NON_EXISTENT_LUN:
1666         case TCM_UNSUPPORTED_SCSI_OPCODE:
1667         case TCM_INVALID_CDB_FIELD:
1668         case TCM_INVALID_PARAMETER_LIST:
1669         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1670         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1671         case TCM_UNKNOWN_MODE_PAGE:
1672         case TCM_WRITE_PROTECTED:
1673         case TCM_ADDRESS_OUT_OF_RANGE:
1674         case TCM_CHECK_CONDITION_ABORT_CMD:
1675         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1676         case TCM_CHECK_CONDITION_NOT_READY:
1677         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1678         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1679         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1680                 break;
1681         case TCM_OUT_OF_RESOURCES:
1682                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1683                 break;
1684         case TCM_RESERVATION_CONFLICT:
1685                 /*
1686                  * No SENSE Data payload for this case, set SCSI Status
1687                  * and queue the response to $FABRIC_MOD.
1688                  *
1689                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1690                  */
1691                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1692                 /*
1693                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1694                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1695                  * CONFLICT STATUS.
1696                  *
1697                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1698                  */
1699                 if (cmd->se_sess &&
1700                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2)
1701                         core_scsi3_ua_allocate(cmd->se_sess->se_node_acl,
1702                                 cmd->orig_fe_lun, 0x2C,
1703                                 ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1704
1705                 trace_target_cmd_complete(cmd);
1706                 ret = cmd->se_tfo-> queue_status(cmd);
1707                 if (ret == -EAGAIN || ret == -ENOMEM)
1708                         goto queue_full;
1709                 goto check_stop;
1710         default:
1711                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1712                         cmd->t_task_cdb[0], sense_reason);
1713                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1714                 break;
1715         }
1716
1717         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1718         if (ret == -EAGAIN || ret == -ENOMEM)
1719                 goto queue_full;
1720
1721 check_stop:
1722         transport_lun_remove_cmd(cmd);
1723         if (!transport_cmd_check_stop_to_fabric(cmd))
1724                 ;
1725         return;
1726
1727 queue_full:
1728         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1729         transport_handle_queue_full(cmd, cmd->se_dev);
1730 }
1731 EXPORT_SYMBOL(transport_generic_request_failure);
1732
1733 void __target_execute_cmd(struct se_cmd *cmd)
1734 {
1735         sense_reason_t ret;
1736
1737         if (cmd->execute_cmd) {
1738                 ret = cmd->execute_cmd(cmd);
1739                 if (ret) {
1740                         spin_lock_irq(&cmd->t_state_lock);
1741                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1742                         spin_unlock_irq(&cmd->t_state_lock);
1743
1744                         transport_generic_request_failure(cmd, ret);
1745                 }
1746         }
1747 }
1748
1749 static int target_write_prot_action(struct se_cmd *cmd)
1750 {
1751         u32 sectors;
1752         /*
1753          * Perform WRITE_INSERT of PI using software emulation when backend
1754          * device has PI enabled, if the transport has not already generated
1755          * PI using hardware WRITE_INSERT offload.
1756          */
1757         switch (cmd->prot_op) {
1758         case TARGET_PROT_DOUT_INSERT:
1759                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1760                         sbc_dif_generate(cmd);
1761                 break;
1762         case TARGET_PROT_DOUT_STRIP:
1763                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1764                         break;
1765
1766                 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1767                 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1768                                              sectors, 0, cmd->t_prot_sg, 0);
1769                 if (unlikely(cmd->pi_err)) {
1770                         spin_lock_irq(&cmd->t_state_lock);
1771                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1772                         spin_unlock_irq(&cmd->t_state_lock);
1773                         transport_generic_request_failure(cmd, cmd->pi_err);
1774                         return -1;
1775                 }
1776                 break;
1777         default:
1778                 break;
1779         }
1780
1781         return 0;
1782 }
1783
1784 static bool target_handle_task_attr(struct se_cmd *cmd)
1785 {
1786         struct se_device *dev = cmd->se_dev;
1787
1788         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1789                 return false;
1790
1791         /*
1792          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1793          * to allow the passed struct se_cmd list of tasks to the front of the list.
1794          */
1795         switch (cmd->sam_task_attr) {
1796         case TCM_HEAD_TAG:
1797                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x, "
1798                          "se_ordered_id: %u\n",
1799                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1800                 return false;
1801         case TCM_ORDERED_TAG:
1802                 atomic_inc_mb(&dev->dev_ordered_sync);
1803
1804                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list, "
1805                          " se_ordered_id: %u\n",
1806                          cmd->t_task_cdb[0], cmd->se_ordered_id);
1807
1808                 /*
1809                  * Execute an ORDERED command if no other older commands
1810                  * exist that need to be completed first.
1811                  */
1812                 if (!atomic_read(&dev->simple_cmds))
1813                         return false;
1814                 break;
1815         default:
1816                 /*
1817                  * For SIMPLE and UNTAGGED Task Attribute commands
1818                  */
1819                 atomic_inc_mb(&dev->simple_cmds);
1820                 break;
1821         }
1822
1823         if (atomic_read(&dev->dev_ordered_sync) == 0)
1824                 return false;
1825
1826         spin_lock(&dev->delayed_cmd_lock);
1827         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1828         spin_unlock(&dev->delayed_cmd_lock);
1829
1830         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to"
1831                 " delayed CMD list, se_ordered_id: %u\n",
1832                 cmd->t_task_cdb[0], cmd->sam_task_attr,
1833                 cmd->se_ordered_id);
1834         return true;
1835 }
1836
1837 void target_execute_cmd(struct se_cmd *cmd)
1838 {
1839         /*
1840          * If the received CDB has aleady been aborted stop processing it here.
1841          */
1842         if (transport_check_aborted_status(cmd, 1))
1843                 return;
1844
1845         /*
1846          * Determine if frontend context caller is requesting the stopping of
1847          * this command for frontend exceptions.
1848          */
1849         spin_lock_irq(&cmd->t_state_lock);
1850         if (cmd->transport_state & CMD_T_STOP) {
1851                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n",
1852                         __func__, __LINE__,
1853                         cmd->se_tfo->get_task_tag(cmd));
1854
1855                 spin_unlock_irq(&cmd->t_state_lock);
1856                 complete_all(&cmd->t_transport_stop_comp);
1857                 return;
1858         }
1859
1860         cmd->t_state = TRANSPORT_PROCESSING;
1861         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1862         spin_unlock_irq(&cmd->t_state_lock);
1863
1864         if (target_write_prot_action(cmd))
1865                 return;
1866
1867         if (target_handle_task_attr(cmd)) {
1868                 spin_lock_irq(&cmd->t_state_lock);
1869                 cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1870                 spin_unlock_irq(&cmd->t_state_lock);
1871                 return;
1872         }
1873
1874         __target_execute_cmd(cmd);
1875 }
1876 EXPORT_SYMBOL(target_execute_cmd);
1877
1878 /*
1879  * Process all commands up to the last received ORDERED task attribute which
1880  * requires another blocking boundary
1881  */
1882 static void target_restart_delayed_cmds(struct se_device *dev)
1883 {
1884         for (;;) {
1885                 struct se_cmd *cmd;
1886
1887                 spin_lock(&dev->delayed_cmd_lock);
1888                 if (list_empty(&dev->delayed_cmd_list)) {
1889                         spin_unlock(&dev->delayed_cmd_lock);
1890                         break;
1891                 }
1892
1893                 cmd = list_entry(dev->delayed_cmd_list.next,
1894                                  struct se_cmd, se_delayed_node);
1895                 list_del(&cmd->se_delayed_node);
1896                 spin_unlock(&dev->delayed_cmd_lock);
1897
1898                 __target_execute_cmd(cmd);
1899
1900                 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1901                         break;
1902         }
1903 }
1904
1905 /*
1906  * Called from I/O completion to determine which dormant/delayed
1907  * and ordered cmds need to have their tasks added to the execution queue.
1908  */
1909 static void transport_complete_task_attr(struct se_cmd *cmd)
1910 {
1911         struct se_device *dev = cmd->se_dev;
1912
1913         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1914                 return;
1915
1916         if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1917                 atomic_dec_mb(&dev->simple_cmds);
1918                 dev->dev_cur_ordered_id++;
1919                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for"
1920                         " SIMPLE: %u\n", dev->dev_cur_ordered_id,
1921                         cmd->se_ordered_id);
1922         } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1923                 dev->dev_cur_ordered_id++;
1924                 pr_debug("Incremented dev_cur_ordered_id: %u for"
1925                         " HEAD_OF_QUEUE: %u\n", dev->dev_cur_ordered_id,
1926                         cmd->se_ordered_id);
1927         } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1928                 atomic_dec_mb(&dev->dev_ordered_sync);
1929
1930                 dev->dev_cur_ordered_id++;
1931                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED:"
1932                         " %u\n", dev->dev_cur_ordered_id, cmd->se_ordered_id);
1933         }
1934
1935         target_restart_delayed_cmds(dev);
1936 }
1937
1938 static void transport_complete_qf(struct se_cmd *cmd)
1939 {
1940         int ret = 0;
1941
1942         transport_complete_task_attr(cmd);
1943
1944         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1945                 trace_target_cmd_complete(cmd);
1946                 ret = cmd->se_tfo->queue_status(cmd);
1947                 goto out;
1948         }
1949
1950         switch (cmd->data_direction) {
1951         case DMA_FROM_DEVICE:
1952                 trace_target_cmd_complete(cmd);
1953                 ret = cmd->se_tfo->queue_data_in(cmd);
1954                 break;
1955         case DMA_TO_DEVICE:
1956                 if (cmd->se_cmd_flags & SCF_BIDI) {
1957                         ret = cmd->se_tfo->queue_data_in(cmd);
1958                         break;
1959                 }
1960                 /* Fall through for DMA_TO_DEVICE */
1961         case DMA_NONE:
1962                 trace_target_cmd_complete(cmd);
1963                 ret = cmd->se_tfo->queue_status(cmd);
1964                 break;
1965         default:
1966                 break;
1967         }
1968
1969 out:
1970         if (ret < 0) {
1971                 transport_handle_queue_full(cmd, cmd->se_dev);
1972                 return;
1973         }
1974         transport_lun_remove_cmd(cmd);
1975         transport_cmd_check_stop_to_fabric(cmd);
1976 }
1977
1978 static void transport_handle_queue_full(
1979         struct se_cmd *cmd,
1980         struct se_device *dev)
1981 {
1982         spin_lock_irq(&dev->qf_cmd_lock);
1983         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
1984         atomic_inc_mb(&dev->dev_qf_count);
1985         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
1986
1987         schedule_work(&cmd->se_dev->qf_work_queue);
1988 }
1989
1990 static bool target_read_prot_action(struct se_cmd *cmd)
1991 {
1992         switch (cmd->prot_op) {
1993         case TARGET_PROT_DIN_STRIP:
1994                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
1995                         u32 sectors = cmd->data_length >>
1996                                   ilog2(cmd->se_dev->dev_attrib.block_size);
1997
1998                         cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1999                                                      sectors, 0, cmd->t_prot_sg,
2000                                                      0);
2001                         if (cmd->pi_err)
2002                                 return true;
2003                 }
2004                 break;
2005         case TARGET_PROT_DIN_INSERT:
2006                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2007                         break;
2008
2009                 sbc_dif_generate(cmd);
2010                 break;
2011         default:
2012                 break;
2013         }
2014
2015         return false;
2016 }
2017
2018 static void target_complete_ok_work(struct work_struct *work)
2019 {
2020         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2021         int ret;
2022
2023         /*
2024          * Check if we need to move delayed/dormant tasks from cmds on the
2025          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2026          * Attribute.
2027          */
2028         transport_complete_task_attr(cmd);
2029
2030         /*
2031          * Check to schedule QUEUE_FULL work, or execute an existing
2032          * cmd->transport_qf_callback()
2033          */
2034         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2035                 schedule_work(&cmd->se_dev->qf_work_queue);
2036
2037         /*
2038          * Check if we need to send a sense buffer from
2039          * the struct se_cmd in question.
2040          */
2041         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2042                 WARN_ON(!cmd->scsi_status);
2043                 ret = transport_send_check_condition_and_sense(
2044                                         cmd, 0, 1);
2045                 if (ret == -EAGAIN || ret == -ENOMEM)
2046                         goto queue_full;
2047
2048                 transport_lun_remove_cmd(cmd);
2049                 transport_cmd_check_stop_to_fabric(cmd);
2050                 return;
2051         }
2052         /*
2053          * Check for a callback, used by amongst other things
2054          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2055          */
2056         if (cmd->transport_complete_callback) {
2057                 sense_reason_t rc;
2058
2059                 rc = cmd->transport_complete_callback(cmd, true);
2060                 if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
2061                         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2062                             !cmd->data_length)
2063                                 goto queue_rsp;
2064
2065                         return;
2066                 } else if (rc) {
2067                         ret = transport_send_check_condition_and_sense(cmd,
2068                                                 rc, 0);
2069                         if (ret == -EAGAIN || ret == -ENOMEM)
2070                                 goto queue_full;
2071
2072                         transport_lun_remove_cmd(cmd);
2073                         transport_cmd_check_stop_to_fabric(cmd);
2074                         return;
2075                 }
2076         }
2077
2078 queue_rsp:
2079         switch (cmd->data_direction) {
2080         case DMA_FROM_DEVICE:
2081                 spin_lock(&cmd->se_lun->lun_sep_lock);
2082                 if (cmd->se_lun->lun_sep) {
2083                         cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
2084                                         cmd->data_length;
2085                 }
2086                 spin_unlock(&cmd->se_lun->lun_sep_lock);
2087                 /*
2088                  * Perform READ_STRIP of PI using software emulation when
2089                  * backend had PI enabled, if the transport will not be
2090                  * performing hardware READ_STRIP offload.
2091                  */
2092                 if (target_read_prot_action(cmd)) {
2093                         ret = transport_send_check_condition_and_sense(cmd,
2094                                                 cmd->pi_err, 0);
2095                         if (ret == -EAGAIN || ret == -ENOMEM)
2096                                 goto queue_full;
2097
2098                         transport_lun_remove_cmd(cmd);
2099                         transport_cmd_check_stop_to_fabric(cmd);
2100                         return;
2101                 }
2102
2103                 trace_target_cmd_complete(cmd);
2104                 ret = cmd->se_tfo->queue_data_in(cmd);
2105                 if (ret == -EAGAIN || ret == -ENOMEM)
2106                         goto queue_full;
2107                 break;
2108         case DMA_TO_DEVICE:
2109                 spin_lock(&cmd->se_lun->lun_sep_lock);
2110                 if (cmd->se_lun->lun_sep) {
2111                         cmd->se_lun->lun_sep->sep_stats.rx_data_octets +=
2112                                 cmd->data_length;
2113                 }
2114                 spin_unlock(&cmd->se_lun->lun_sep_lock);
2115                 /*
2116                  * Check if we need to send READ payload for BIDI-COMMAND
2117                  */
2118                 if (cmd->se_cmd_flags & SCF_BIDI) {
2119                         spin_lock(&cmd->se_lun->lun_sep_lock);
2120                         if (cmd->se_lun->lun_sep) {
2121                                 cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
2122                                         cmd->data_length;
2123                         }
2124                         spin_unlock(&cmd->se_lun->lun_sep_lock);
2125                         ret = cmd->se_tfo->queue_data_in(cmd);
2126                         if (ret == -EAGAIN || ret == -ENOMEM)
2127                                 goto queue_full;
2128                         break;
2129                 }
2130                 /* Fall through for DMA_TO_DEVICE */
2131         case DMA_NONE:
2132                 trace_target_cmd_complete(cmd);
2133                 ret = cmd->se_tfo->queue_status(cmd);
2134                 if (ret == -EAGAIN || ret == -ENOMEM)
2135                         goto queue_full;
2136                 break;
2137         default:
2138                 break;
2139         }
2140
2141         transport_lun_remove_cmd(cmd);
2142         transport_cmd_check_stop_to_fabric(cmd);
2143         return;
2144
2145 queue_full:
2146         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2147                 " data_direction: %d\n", cmd, cmd->data_direction);
2148         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2149         transport_handle_queue_full(cmd, cmd->se_dev);
2150 }
2151
2152 static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
2153 {
2154         struct scatterlist *sg;
2155         int count;
2156
2157         for_each_sg(sgl, sg, nents, count)
2158                 __free_page(sg_page(sg));
2159
2160         kfree(sgl);
2161 }
2162
2163 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2164 {
2165         /*
2166          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2167          * emulation, and free + reset pointers if necessary..
2168          */
2169         if (!cmd->t_data_sg_orig)
2170                 return;
2171
2172         kfree(cmd->t_data_sg);
2173         cmd->t_data_sg = cmd->t_data_sg_orig;
2174         cmd->t_data_sg_orig = NULL;
2175         cmd->t_data_nents = cmd->t_data_nents_orig;
2176         cmd->t_data_nents_orig = 0;
2177 }
2178
2179 static inline void transport_free_pages(struct se_cmd *cmd)
2180 {
2181         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2182                 /*
2183                  * Release special case READ buffer payload required for
2184                  * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2185                  */
2186                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2187                         transport_free_sgl(cmd->t_bidi_data_sg,
2188                                            cmd->t_bidi_data_nents);
2189                         cmd->t_bidi_data_sg = NULL;
2190                         cmd->t_bidi_data_nents = 0;
2191                 }
2192                 transport_reset_sgl_orig(cmd);
2193                 return;
2194         }
2195         transport_reset_sgl_orig(cmd);
2196
2197         transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2198         cmd->t_data_sg = NULL;
2199         cmd->t_data_nents = 0;
2200
2201         transport_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2202         cmd->t_bidi_data_sg = NULL;
2203         cmd->t_bidi_data_nents = 0;
2204
2205         transport_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2206         cmd->t_prot_sg = NULL;
2207         cmd->t_prot_nents = 0;
2208 }
2209
2210 /**
2211  * transport_release_cmd - free a command
2212  * @cmd:       command to free
2213  *
2214  * This routine unconditionally frees a command, and reference counting
2215  * or list removal must be done in the caller.
2216  */
2217 static int transport_release_cmd(struct se_cmd *cmd)
2218 {
2219         BUG_ON(!cmd->se_tfo);
2220
2221         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2222                 core_tmr_release_req(cmd->se_tmr_req);
2223         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2224                 kfree(cmd->t_task_cdb);
2225         /*
2226          * If this cmd has been setup with target_get_sess_cmd(), drop
2227          * the kref and call ->release_cmd() in kref callback.
2228          */
2229         return target_put_sess_cmd(cmd);
2230 }
2231
2232 /**
2233  * transport_put_cmd - release a reference to a command
2234  * @cmd:       command to release
2235  *
2236  * This routine releases our reference to the command and frees it if possible.
2237  */
2238 static int transport_put_cmd(struct se_cmd *cmd)
2239 {
2240         transport_free_pages(cmd);
2241         return transport_release_cmd(cmd);
2242 }
2243
2244 void *transport_kmap_data_sg(struct se_cmd *cmd)
2245 {
2246         struct scatterlist *sg = cmd->t_data_sg;
2247         struct page **pages;
2248         int i;
2249
2250         /*
2251          * We need to take into account a possible offset here for fabrics like
2252          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2253          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2254          */
2255         if (!cmd->t_data_nents)
2256                 return NULL;
2257
2258         BUG_ON(!sg);
2259         if (cmd->t_data_nents == 1)
2260                 return kmap(sg_page(sg)) + sg->offset;
2261
2262         /* >1 page. use vmap */
2263         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2264         if (!pages)
2265                 return NULL;
2266
2267         /* convert sg[] to pages[] */
2268         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2269                 pages[i] = sg_page(sg);
2270         }
2271
2272         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2273         kfree(pages);
2274         if (!cmd->t_data_vmap)
2275                 return NULL;
2276
2277         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2278 }
2279 EXPORT_SYMBOL(transport_kmap_data_sg);
2280
2281 void transport_kunmap_data_sg(struct se_cmd *cmd)
2282 {
2283         if (!cmd->t_data_nents) {
2284                 return;
2285         } else if (cmd->t_data_nents == 1) {
2286                 kunmap(sg_page(cmd->t_data_sg));
2287                 return;
2288         }
2289
2290         vunmap(cmd->t_data_vmap);
2291         cmd->t_data_vmap = NULL;
2292 }
2293 EXPORT_SYMBOL(transport_kunmap_data_sg);
2294
2295 int
2296 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2297                  bool zero_page)
2298 {
2299         struct scatterlist *sg;
2300         struct page *page;
2301         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2302         unsigned int nent;
2303         int i = 0;
2304
2305         nent = DIV_ROUND_UP(length, PAGE_SIZE);
2306         sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
2307         if (!sg)
2308                 return -ENOMEM;
2309
2310         sg_init_table(sg, nent);
2311
2312         while (length) {
2313                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2314                 page = alloc_page(GFP_KERNEL | zero_flag);
2315                 if (!page)
2316                         goto out;
2317
2318                 sg_set_page(&sg[i], page, page_len, 0);
2319                 length -= page_len;
2320                 i++;
2321         }
2322         *sgl = sg;
2323         *nents = nent;
2324         return 0;
2325
2326 out:
2327         while (i > 0) {
2328                 i--;
2329                 __free_page(sg_page(&sg[i]));
2330         }
2331         kfree(sg);
2332         return -ENOMEM;
2333 }
2334
2335 /*
2336  * Allocate any required resources to execute the command.  For writes we
2337  * might not have the payload yet, so notify the fabric via a call to
2338  * ->write_pending instead. Otherwise place it on the execution queue.
2339  */
2340 sense_reason_t
2341 transport_generic_new_cmd(struct se_cmd *cmd)
2342 {
2343         int ret = 0;
2344         bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2345
2346         /*
2347          * Determine is the TCM fabric module has already allocated physical
2348          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2349          * beforehand.
2350          */
2351         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2352             cmd->data_length) {
2353
2354                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2355                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2356                         u32 bidi_length;
2357
2358                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2359                                 bidi_length = cmd->t_task_nolb *
2360                                               cmd->se_dev->dev_attrib.block_size;
2361                         else
2362                                 bidi_length = cmd->data_length;
2363
2364                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2365                                                &cmd->t_bidi_data_nents,
2366                                                bidi_length, zero_flag);
2367                         if (ret < 0)
2368                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2369                 }
2370
2371                 if (cmd->prot_op != TARGET_PROT_NORMAL) {
2372                         ret = target_alloc_sgl(&cmd->t_prot_sg,
2373                                                &cmd->t_prot_nents,
2374                                                cmd->prot_length, true);
2375                         if (ret < 0)
2376                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2377                 }
2378
2379                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2380                                        cmd->data_length, zero_flag);
2381                 if (ret < 0)
2382                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2383         } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2384                     cmd->data_length) {
2385                 /*
2386                  * Special case for COMPARE_AND_WRITE with fabrics
2387                  * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2388                  */
2389                 u32 caw_length = cmd->t_task_nolb *
2390                                  cmd->se_dev->dev_attrib.block_size;
2391
2392                 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2393                                        &cmd->t_bidi_data_nents,
2394                                        caw_length, zero_flag);
2395                 if (ret < 0)
2396                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2397         }
2398         /*
2399          * If this command is not a write we can execute it right here,
2400          * for write buffers we need to notify the fabric driver first
2401          * and let it call back once the write buffers are ready.
2402          */
2403         target_add_to_state_list(cmd);
2404         if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2405                 target_execute_cmd(cmd);
2406                 return 0;
2407         }
2408         transport_cmd_check_stop(cmd, false, true);
2409
2410         ret = cmd->se_tfo->write_pending(cmd);
2411         if (ret == -EAGAIN || ret == -ENOMEM)
2412                 goto queue_full;
2413
2414         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2415         WARN_ON(ret);
2416
2417         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2418
2419 queue_full:
2420         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2421         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2422         transport_handle_queue_full(cmd, cmd->se_dev);
2423         return 0;
2424 }
2425 EXPORT_SYMBOL(transport_generic_new_cmd);
2426
2427 static void transport_write_pending_qf(struct se_cmd *cmd)
2428 {
2429         int ret;
2430
2431         ret = cmd->se_tfo->write_pending(cmd);
2432         if (ret == -EAGAIN || ret == -ENOMEM) {
2433                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2434                          cmd);
2435                 transport_handle_queue_full(cmd, cmd->se_dev);
2436         }
2437 }
2438
2439 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2440 {
2441         unsigned long flags;
2442         int ret = 0;
2443
2444         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2445                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2446                          transport_wait_for_tasks(cmd);
2447
2448                 ret = transport_release_cmd(cmd);
2449         } else {
2450                 if (wait_for_tasks)
2451                         transport_wait_for_tasks(cmd);
2452                 /*
2453                  * Handle WRITE failure case where transport_generic_new_cmd()
2454                  * has already added se_cmd to state_list, but fabric has
2455                  * failed command before I/O submission.
2456                  */
2457                 if (cmd->state_active) {
2458                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2459                         target_remove_from_state_list(cmd);
2460                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2461                 }
2462
2463                 if (cmd->se_lun)
2464                         transport_lun_remove_cmd(cmd);
2465
2466                 ret = transport_put_cmd(cmd);
2467         }
2468         return ret;
2469 }
2470 EXPORT_SYMBOL(transport_generic_free_cmd);
2471
2472 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2473  * @se_cmd:     command descriptor to add
2474  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2475  */
2476 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2477 {
2478         struct se_session *se_sess = se_cmd->se_sess;
2479         unsigned long flags;
2480         int ret = 0;
2481
2482         /*
2483          * Add a second kref if the fabric caller is expecting to handle
2484          * fabric acknowledgement that requires two target_put_sess_cmd()
2485          * invocations before se_cmd descriptor release.
2486          */
2487         if (ack_kref)
2488                 kref_get(&se_cmd->cmd_kref);
2489
2490         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2491         if (se_sess->sess_tearing_down) {
2492                 ret = -ESHUTDOWN;
2493                 goto out;
2494         }
2495         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2496 out:
2497         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2498
2499         if (ret && ack_kref)
2500                 target_put_sess_cmd(se_cmd);
2501
2502         return ret;
2503 }
2504 EXPORT_SYMBOL(target_get_sess_cmd);
2505
2506 static void target_release_cmd_kref(struct kref *kref)
2507                 __releases(&se_cmd->se_sess->sess_cmd_lock)
2508 {
2509         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2510         struct se_session *se_sess = se_cmd->se_sess;
2511
2512         if (list_empty(&se_cmd->se_cmd_list)) {
2513                 spin_unlock(&se_sess->sess_cmd_lock);
2514                 se_cmd->se_tfo->release_cmd(se_cmd);
2515                 return;
2516         }
2517         if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) {
2518                 spin_unlock(&se_sess->sess_cmd_lock);
2519                 complete(&se_cmd->cmd_wait_comp);
2520                 return;
2521         }
2522         list_del(&se_cmd->se_cmd_list);
2523         spin_unlock(&se_sess->sess_cmd_lock);
2524
2525         se_cmd->se_tfo->release_cmd(se_cmd);
2526 }
2527
2528 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2529  * @se_cmd:     command descriptor to drop
2530  */
2531 int target_put_sess_cmd(struct se_cmd *se_cmd)
2532 {
2533         struct se_session *se_sess = se_cmd->se_sess;
2534
2535         if (!se_sess) {
2536                 se_cmd->se_tfo->release_cmd(se_cmd);
2537                 return 1;
2538         }
2539         return kref_put_spinlock_irqsave(&se_cmd->cmd_kref, target_release_cmd_kref,
2540                         &se_sess->sess_cmd_lock);
2541 }
2542 EXPORT_SYMBOL(target_put_sess_cmd);
2543
2544 /* target_sess_cmd_list_set_waiting - Flag all commands in
2545  *         sess_cmd_list to complete cmd_wait_comp.  Set
2546  *         sess_tearing_down so no more commands are queued.
2547  * @se_sess:    session to flag
2548  */
2549 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2550 {
2551         struct se_cmd *se_cmd;
2552         unsigned long flags;
2553
2554         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2555         if (se_sess->sess_tearing_down) {
2556                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2557                 return;
2558         }
2559         se_sess->sess_tearing_down = 1;
2560         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2561
2562         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list)
2563                 se_cmd->cmd_wait_set = 1;
2564
2565         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2566 }
2567 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2568
2569 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2570  * @se_sess:    session to wait for active I/O
2571  */
2572 void target_wait_for_sess_cmds(struct se_session *se_sess)
2573 {
2574         struct se_cmd *se_cmd, *tmp_cmd;
2575         unsigned long flags;
2576
2577         list_for_each_entry_safe(se_cmd, tmp_cmd,
2578                                 &se_sess->sess_wait_list, se_cmd_list) {
2579                 list_del(&se_cmd->se_cmd_list);
2580
2581                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2582                         " %d\n", se_cmd, se_cmd->t_state,
2583                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2584
2585                 wait_for_completion(&se_cmd->cmd_wait_comp);
2586                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2587                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2588                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2589
2590                 se_cmd->se_tfo->release_cmd(se_cmd);
2591         }
2592
2593         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2594         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2595         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2596
2597 }
2598 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2599
2600 static int transport_clear_lun_ref_thread(void *p)
2601 {
2602         struct se_lun *lun = p;
2603
2604         percpu_ref_kill(&lun->lun_ref);
2605
2606         wait_for_completion(&lun->lun_ref_comp);
2607         complete(&lun->lun_shutdown_comp);
2608
2609         return 0;
2610 }
2611
2612 int transport_clear_lun_ref(struct se_lun *lun)
2613 {
2614         struct task_struct *kt;
2615
2616         kt = kthread_run(transport_clear_lun_ref_thread, lun,
2617                         "tcm_cl_%u", lun->unpacked_lun);
2618         if (IS_ERR(kt)) {
2619                 pr_err("Unable to start clear_lun thread\n");
2620                 return PTR_ERR(kt);
2621         }
2622         wait_for_completion(&lun->lun_shutdown_comp);
2623
2624         return 0;
2625 }
2626
2627 /**
2628  * transport_wait_for_tasks - wait for completion to occur
2629  * @cmd:        command to wait
2630  *
2631  * Called from frontend fabric context to wait for storage engine
2632  * to pause and/or release frontend generated struct se_cmd.
2633  */
2634 bool transport_wait_for_tasks(struct se_cmd *cmd)
2635 {
2636         unsigned long flags;
2637
2638         spin_lock_irqsave(&cmd->t_state_lock, flags);
2639         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2640             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2641                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2642                 return false;
2643         }
2644
2645         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2646             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
2647                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2648                 return false;
2649         }
2650
2651         if (!(cmd->transport_state & CMD_T_ACTIVE)) {
2652                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2653                 return false;
2654         }
2655
2656         cmd->transport_state |= CMD_T_STOP;
2657
2658         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08x"
2659                 " i_state: %d, t_state: %d, CMD_T_STOP\n",
2660                 cmd, cmd->se_tfo->get_task_tag(cmd),
2661                 cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2662
2663         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2664
2665         wait_for_completion(&cmd->t_transport_stop_comp);
2666
2667         spin_lock_irqsave(&cmd->t_state_lock, flags);
2668         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2669
2670         pr_debug("wait_for_tasks: Stopped wait_for_completion("
2671                 "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n",
2672                 cmd->se_tfo->get_task_tag(cmd));
2673
2674         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2675
2676         return true;
2677 }
2678 EXPORT_SYMBOL(transport_wait_for_tasks);
2679
2680 static int transport_get_sense_codes(
2681         struct se_cmd *cmd,
2682         u8 *asc,
2683         u8 *ascq)
2684 {
2685         *asc = cmd->scsi_asc;
2686         *ascq = cmd->scsi_ascq;
2687
2688         return 0;
2689 }
2690
2691 static
2692 void transport_err_sector_info(unsigned char *buffer, sector_t bad_sector)
2693 {
2694         /* Place failed LBA in sense data information descriptor 0. */
2695         buffer[SPC_ADD_SENSE_LEN_OFFSET] = 0xc;
2696         buffer[SPC_DESC_TYPE_OFFSET] = 0; /* Information */
2697         buffer[SPC_ADDITIONAL_DESC_LEN_OFFSET] = 0xa;
2698         buffer[SPC_VALIDITY_OFFSET] = 0x80;
2699
2700         /* Descriptor Information: failing sector */
2701         put_unaligned_be64(bad_sector, &buffer[12]);
2702 }
2703
2704 int
2705 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2706                 sense_reason_t reason, int from_transport)
2707 {
2708         unsigned char *buffer = cmd->sense_buffer;
2709         unsigned long flags;
2710         u8 asc = 0, ascq = 0;
2711
2712         spin_lock_irqsave(&cmd->t_state_lock, flags);
2713         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2714                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2715                 return 0;
2716         }
2717         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2718         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2719
2720         if (!reason && from_transport)
2721                 goto after_reason;
2722
2723         if (!from_transport)
2724                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2725
2726         /*
2727          * Actual SENSE DATA, see SPC-3 7.23.2  SPC_SENSE_KEY_OFFSET uses
2728          * SENSE KEY values from include/scsi/scsi.h
2729          */
2730         switch (reason) {
2731         case TCM_NO_SENSE:
2732                 /* CURRENT ERROR */
2733                 buffer[0] = 0x70;
2734                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2735                 /* Not Ready */
2736                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2737                 /* NO ADDITIONAL SENSE INFORMATION */
2738                 buffer[SPC_ASC_KEY_OFFSET] = 0;
2739                 buffer[SPC_ASCQ_KEY_OFFSET] = 0;
2740                 break;
2741         case TCM_NON_EXISTENT_LUN:
2742                 /* CURRENT ERROR */
2743                 buffer[0] = 0x70;
2744                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2745                 /* ILLEGAL REQUEST */
2746                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2747                 /* LOGICAL UNIT NOT SUPPORTED */
2748                 buffer[SPC_ASC_KEY_OFFSET] = 0x25;
2749                 break;
2750         case TCM_UNSUPPORTED_SCSI_OPCODE:
2751         case TCM_SECTOR_COUNT_TOO_MANY:
2752                 /* CURRENT ERROR */
2753                 buffer[0] = 0x70;
2754                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2755                 /* ILLEGAL REQUEST */
2756                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2757                 /* INVALID COMMAND OPERATION CODE */
2758                 buffer[SPC_ASC_KEY_OFFSET] = 0x20;
2759                 break;
2760         case TCM_UNKNOWN_MODE_PAGE:
2761                 /* CURRENT ERROR */
2762                 buffer[0] = 0x70;
2763                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2764                 /* ILLEGAL REQUEST */
2765                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2766                 /* INVALID FIELD IN CDB */
2767                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2768                 break;
2769         case TCM_CHECK_CONDITION_ABORT_CMD:
2770                 /* CURRENT ERROR */
2771                 buffer[0] = 0x70;
2772                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2773                 /* ABORTED COMMAND */
2774                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2775                 /* BUS DEVICE RESET FUNCTION OCCURRED */
2776                 buffer[SPC_ASC_KEY_OFFSET] = 0x29;
2777                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2778                 break;
2779         case TCM_INCORRECT_AMOUNT_OF_DATA:
2780                 /* CURRENT ERROR */
2781                 buffer[0] = 0x70;
2782                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2783                 /* ABORTED COMMAND */
2784                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2785                 /* WRITE ERROR */
2786                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2787                 /* NOT ENOUGH UNSOLICITED DATA */
2788                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0d;
2789                 break;
2790         case TCM_INVALID_CDB_FIELD:
2791                 /* CURRENT ERROR */
2792                 buffer[0] = 0x70;
2793                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2794                 /* ILLEGAL REQUEST */
2795                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2796                 /* INVALID FIELD IN CDB */
2797                 buffer[SPC_ASC_KEY_OFFSET] = 0x24;
2798                 break;
2799         case TCM_INVALID_PARAMETER_LIST:
2800                 /* CURRENT ERROR */
2801                 buffer[0] = 0x70;
2802                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2803                 /* ILLEGAL REQUEST */
2804                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2805                 /* INVALID FIELD IN PARAMETER LIST */
2806                 buffer[SPC_ASC_KEY_OFFSET] = 0x26;
2807                 break;
2808         case TCM_PARAMETER_LIST_LENGTH_ERROR:
2809                 /* CURRENT ERROR */
2810                 buffer[0] = 0x70;
2811                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2812                 /* ILLEGAL REQUEST */
2813                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2814                 /* PARAMETER LIST LENGTH ERROR */
2815                 buffer[SPC_ASC_KEY_OFFSET] = 0x1a;
2816                 break;
2817         case TCM_UNEXPECTED_UNSOLICITED_DATA:
2818                 /* CURRENT ERROR */
2819                 buffer[0] = 0x70;
2820                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2821                 /* ABORTED COMMAND */
2822                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2823                 /* WRITE ERROR */
2824                 buffer[SPC_ASC_KEY_OFFSET] = 0x0c;
2825                 /* UNEXPECTED_UNSOLICITED_DATA */
2826                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x0c;
2827                 break;
2828         case TCM_SERVICE_CRC_ERROR:
2829                 /* CURRENT ERROR */
2830                 buffer[0] = 0x70;
2831                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2832                 /* ABORTED COMMAND */
2833                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2834                 /* PROTOCOL SERVICE CRC ERROR */
2835                 buffer[SPC_ASC_KEY_OFFSET] = 0x47;
2836                 /* N/A */
2837                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x05;
2838                 break;
2839         case TCM_SNACK_REJECTED:
2840                 /* CURRENT ERROR */
2841                 buffer[0] = 0x70;
2842                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2843                 /* ABORTED COMMAND */
2844                 buffer[SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND;
2845                 /* READ ERROR */
2846                 buffer[SPC_ASC_KEY_OFFSET] = 0x11;
2847                 /* FAILED RETRANSMISSION REQUEST */
2848                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x13;
2849                 break;
2850         case TCM_WRITE_PROTECTED:
2851                 /* CURRENT ERROR */
2852                 buffer[0] = 0x70;
2853                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2854                 /* DATA PROTECT */
2855                 buffer[SPC_SENSE_KEY_OFFSET] = DATA_PROTECT;
2856                 /* WRITE PROTECTED */
2857                 buffer[SPC_ASC_KEY_OFFSET] = 0x27;
2858                 break;
2859         case TCM_ADDRESS_OUT_OF_RANGE:
2860                 /* CURRENT ERROR */
2861                 buffer[0] = 0x70;
2862                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2863                 /* ILLEGAL REQUEST */
2864                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2865                 /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2866                 buffer[SPC_ASC_KEY_OFFSET] = 0x21;
2867                 break;
2868         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2869                 /* CURRENT ERROR */
2870                 buffer[0] = 0x70;
2871                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2872                 /* UNIT ATTENTION */
2873                 buffer[SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION;
2874                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2875                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2876                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2877                 break;
2878         case TCM_CHECK_CONDITION_NOT_READY:
2879                 /* CURRENT ERROR */
2880                 buffer[0] = 0x70;
2881                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2882                 /* Not Ready */
2883                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2884                 transport_get_sense_codes(cmd, &asc, &ascq);
2885                 buffer[SPC_ASC_KEY_OFFSET] = asc;
2886                 buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
2887                 break;
2888         case TCM_MISCOMPARE_VERIFY:
2889                 /* CURRENT ERROR */
2890                 buffer[0] = 0x70;
2891                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2892                 buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
2893                 /* MISCOMPARE DURING VERIFY OPERATION */
2894                 buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
2895                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
2896                 break;
2897         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
2898                 /* CURRENT ERROR */
2899                 buffer[0] = 0x70;
2900                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2901                 /* ILLEGAL REQUEST */
2902                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2903                 /* LOGICAL BLOCK GUARD CHECK FAILED */
2904                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2905                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x01;
2906                 transport_err_sector_info(buffer, cmd->bad_sector);
2907                 break;
2908         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
2909                 /* CURRENT ERROR */
2910                 buffer[0] = 0x70;
2911                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2912                 /* ILLEGAL REQUEST */
2913                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2914                 /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2915                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2916                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x02;
2917                 transport_err_sector_info(buffer, cmd->bad_sector);
2918                 break;
2919         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
2920                 /* CURRENT ERROR */
2921                 buffer[0] = 0x70;
2922                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2923                 /* ILLEGAL REQUEST */
2924                 buffer[SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST;
2925                 /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2926                 buffer[SPC_ASC_KEY_OFFSET] = 0x10;
2927                 buffer[SPC_ASCQ_KEY_OFFSET] = 0x03;
2928                 transport_err_sector_info(buffer, cmd->bad_sector);
2929                 break;
2930         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2931         default:
2932                 /* CURRENT ERROR */
2933                 buffer[0] = 0x70;
2934                 buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
2935                 /*
2936                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2937                  * Solaris initiators.  Returning NOT READY instead means the
2938                  * operations will be retried a finite number of times and we
2939                  * can survive intermittent errors.
2940                  */
2941                 buffer[SPC_SENSE_KEY_OFFSET] = NOT_READY;
2942                 /* LOGICAL UNIT COMMUNICATION FAILURE */
2943                 buffer[SPC_ASC_KEY_OFFSET] = 0x08;
2944                 break;
2945         }
2946         /*
2947          * This code uses linux/include/scsi/scsi.h SAM status codes!
2948          */
2949         cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2950         /*
2951          * Automatically padded, this value is encoded in the fabric's
2952          * data_length response PDU containing the SCSI defined sense data.
2953          */
2954         cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2955
2956 after_reason:
2957         trace_target_cmd_complete(cmd);
2958         return cmd->se_tfo->queue_status(cmd);
2959 }
2960 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2961
2962 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2963 {
2964         if (!(cmd->transport_state & CMD_T_ABORTED))
2965                 return 0;
2966
2967         /*
2968          * If cmd has been aborted but either no status is to be sent or it has
2969          * already been sent, just return
2970          */
2971         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
2972                 return 1;
2973
2974         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
2975                  cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
2976
2977         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2978         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2979         trace_target_cmd_complete(cmd);
2980         cmd->se_tfo->queue_status(cmd);
2981
2982         return 1;
2983 }
2984 EXPORT_SYMBOL(transport_check_aborted_status);
2985
2986 void transport_send_task_abort(struct se_cmd *cmd)
2987 {
2988         unsigned long flags;
2989
2990         spin_lock_irqsave(&cmd->t_state_lock, flags);
2991         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2992                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2993                 return;
2994         }
2995         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2996
2997         /*
2998          * If there are still expected incoming fabric WRITEs, we wait
2999          * until until they have completed before sending a TASK_ABORTED
3000          * response.  This response with TASK_ABORTED status will be
3001          * queued back to fabric module by transport_check_aborted_status().
3002          */
3003         if (cmd->data_direction == DMA_TO_DEVICE) {
3004                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
3005                         cmd->transport_state |= CMD_T_ABORTED;
3006                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
3007                         return;
3008                 }
3009         }
3010         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3011
3012         transport_lun_remove_cmd(cmd);
3013
3014         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x,"
3015                 " ITT: 0x%08x\n", cmd->t_task_cdb[0],
3016                 cmd->se_tfo->get_task_tag(cmd));
3017
3018         trace_target_cmd_complete(cmd);
3019         cmd->se_tfo->queue_status(cmd);
3020 }
3021
3022 static void target_tmr_work(struct work_struct *work)
3023 {
3024         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3025         struct se_device *dev = cmd->se_dev;
3026         struct se_tmr_req *tmr = cmd->se_tmr_req;
3027         int ret;
3028
3029         switch (tmr->function) {
3030         case TMR_ABORT_TASK:
3031                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3032                 break;
3033         case TMR_ABORT_TASK_SET:
3034         case TMR_CLEAR_ACA:
3035         case TMR_CLEAR_TASK_SET:
3036                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3037                 break;
3038         case TMR_LUN_RESET:
3039                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3040                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3041                                          TMR_FUNCTION_REJECTED;
3042                 break;
3043         case TMR_TARGET_WARM_RESET:
3044                 tmr->response = TMR_FUNCTION_REJECTED;
3045                 break;
3046         case TMR_TARGET_COLD_RESET:
3047                 tmr->response = TMR_FUNCTION_REJECTED;
3048                 break;
3049         default:
3050                 pr_err("Uknown TMR function: 0x%02x.\n",
3051                                 tmr->function);
3052                 tmr->response = TMR_FUNCTION_REJECTED;
3053                 break;
3054         }
3055
3056         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3057         cmd->se_tfo->queue_tm_rsp(cmd);
3058
3059         transport_cmd_check_stop_to_fabric(cmd);
3060 }
3061
3062 int transport_generic_handle_tmr(
3063         struct se_cmd *cmd)
3064 {
3065         unsigned long flags;
3066
3067         spin_lock_irqsave(&cmd->t_state_lock, flags);
3068         cmd->transport_state |= CMD_T_ACTIVE;
3069         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3070
3071         INIT_WORK(&cmd->work, target_tmr_work);
3072         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3073         return 0;
3074 }
3075 EXPORT_SYMBOL(transport_generic_handle_tmr);
3076
3077 bool
3078 target_check_wce(struct se_device *dev)
3079 {
3080         bool wce = false;
3081
3082         if (dev->transport->get_write_cache)
3083                 wce = dev->transport->get_write_cache(dev);
3084         else if (dev->dev_attrib.emulate_write_cache > 0)
3085                 wce = true;
3086
3087         return wce;
3088 }
3089
3090 bool
3091 target_check_fua(struct se_device *dev)
3092 {
3093         return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3094 }