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