drivers/target/target_core_transport.c

   1 /*******************************************************************************
   2  * Filename:  target_core_transport.c
   3  *
   4  * This file contains the Generic Target Engine Core.
   5  *
   6  * (c) Copyright 2002-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/net.h>
  27 #include <linux/delay.h>
  28 #include <linux/string.h>
  29 #include <linux/timer.h>
  30 #include <linux/slab.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/kthread.h>
  33 #include <linux/in.h>
  34 #include <linux/cdrom.h>
  35 #include <linux/module.h>
  36 #include <linux/ratelimit.h>
  37 #include <linux/vmalloc.h>
  38 #include <asm/unaligned.h>
  39 #include <net/sock.h>
  40 #include <net/tcp.h>
  41 #include <scsi/scsi_proto.h>
  42 #include <scsi/scsi_common.h>
  43
  44 #include <target/target_core_base.h>
  45 #include <target/target_core_backend.h>
  46 #include <target/target_core_fabric.h>
  47
  48 #include "target_core_internal.h"
  49 #include "target_core_alua.h"
  50 #include "target_core_pr.h"
  51 #include "target_core_ua.h"
  52
  53 #define CREATE_TRACE_POINTS
  54 #include <trace/events/target.h>
  55
  56 static struct workqueue_struct *target_completion_wq;
  57 static struct kmem_cache *se_sess_cache;
  58 struct kmem_cache *se_ua_cache;
  59 struct kmem_cache *t10_pr_reg_cache;
  60 struct kmem_cache *t10_alua_lu_gp_cache;
  61 struct kmem_cache *t10_alua_lu_gp_mem_cache;
  62 struct kmem_cache *t10_alua_tg_pt_gp_cache;
  63 struct kmem_cache *t10_alua_lba_map_cache;
  64 struct kmem_cache *t10_alua_lba_map_mem_cache;
  65
  66 static void transport_complete_task_attr(struct se_cmd *cmd);
  67 static void transport_handle_queue_full(struct se_cmd *cmd,
  68                 struct se_device *dev);
  69 static int transport_put_cmd(struct se_cmd *cmd);
  70 static void target_complete_ok_work(struct work_struct *work);
  71
  72 int init_se_kmem_caches(void)
  73 {
  74         se_sess_cache = kmem_cache_create("se_sess_cache",
  75                         sizeof(struct se_session), __alignof__(struct se_session),
  76                         0, NULL);
  77         if (!se_sess_cache) {
  78                 pr_err("kmem_cache_create() for struct se_session"
  79                                 " failed\n");
  80                 goto out;
  81         }
  82         se_ua_cache = kmem_cache_create("se_ua_cache",
  83                         sizeof(struct se_ua), __alignof__(struct se_ua),
  84                         0, NULL);
  85         if (!se_ua_cache) {
  86                 pr_err("kmem_cache_create() for struct se_ua failed\n");
  87                 goto out_free_sess_cache;
  88         }
  89         t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  90                         sizeof(struct t10_pr_registration),
  91                         __alignof__(struct t10_pr_registration), 0, NULL);
  92         if (!t10_pr_reg_cache) {
  93                 pr_err("kmem_cache_create() for struct t10_pr_registration"
  94                                 " failed\n");
  95                 goto out_free_ua_cache;
  96         }
  97         t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
  98                         sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
  99                         0, NULL);
 100         if (!t10_alua_lu_gp_cache) {
 101                 pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
 102                                 " failed\n");
 103                 goto out_free_pr_reg_cache;
 104         }
 105         t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
 106                         sizeof(struct t10_alua_lu_gp_member),
 107                         __alignof__(struct t10_alua_lu_gp_member), 0, NULL);
 108         if (!t10_alua_lu_gp_mem_cache) {
 109                 pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
 110                                 "cache failed\n");
 111                 goto out_free_lu_gp_cache;
 112         }
 113         t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 114                         sizeof(struct t10_alua_tg_pt_gp),
 115                         __alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 116         if (!t10_alua_tg_pt_gp_cache) {
 117                 pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 118                                 "cache failed\n");
 119                 goto out_free_lu_gp_mem_cache;
 120         }
 121         t10_alua_lba_map_cache = kmem_cache_create(
 122                         "t10_alua_lba_map_cache",
 123                         sizeof(struct t10_alua_lba_map),
 124                         __alignof__(struct t10_alua_lba_map), 0, NULL);
 125         if (!t10_alua_lba_map_cache) {
 126                 pr_err("kmem_cache_create() for t10_alua_lba_map_"
 127                                 "cache failed\n");
 128                 goto out_free_tg_pt_gp_cache;
 129         }
 130         t10_alua_lba_map_mem_cache = kmem_cache_create(
 131                         "t10_alua_lba_map_mem_cache",
 132                         sizeof(struct t10_alua_lba_map_member),
 133                         __alignof__(struct t10_alua_lba_map_member), 0, NULL);
 134         if (!t10_alua_lba_map_mem_cache) {
 135                 pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
 136                                 "cache failed\n");
 137                 goto out_free_lba_map_cache;
 138         }
 139
 140         target_completion_wq = alloc_workqueue("target_completion",
 141                                                WQ_MEM_RECLAIM, 0);
 142         if (!target_completion_wq)
 143                 goto out_free_lba_map_mem_cache;
 144
 145         return 0;
 146
 147 out_free_lba_map_mem_cache:
 148         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 149 out_free_lba_map_cache:
 150         kmem_cache_destroy(t10_alua_lba_map_cache);
 151 out_free_tg_pt_gp_cache:
 152         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 153 out_free_lu_gp_mem_cache:
 154         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 155 out_free_lu_gp_cache:
 156         kmem_cache_destroy(t10_alua_lu_gp_cache);
 157 out_free_pr_reg_cache:
 158         kmem_cache_destroy(t10_pr_reg_cache);
 159 out_free_ua_cache:
 160         kmem_cache_destroy(se_ua_cache);
 161 out_free_sess_cache:
 162         kmem_cache_destroy(se_sess_cache);
 163 out:
 164         return -ENOMEM;
 165 }
 166
 167 void release_se_kmem_caches(void)
 168 {
 169         destroy_workqueue(target_completion_wq);
 170         kmem_cache_destroy(se_sess_cache);
 171         kmem_cache_destroy(se_ua_cache);
 172         kmem_cache_destroy(t10_pr_reg_cache);
 173         kmem_cache_destroy(t10_alua_lu_gp_cache);
 174         kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 175         kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 176         kmem_cache_destroy(t10_alua_lba_map_cache);
 177         kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 178 }
 179
 180 /* This code ensures unique mib indexes are handed out. */
 181 static DEFINE_SPINLOCK(scsi_mib_index_lock);
 182 static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 183
 184 /*
 185  * Allocate a new row index for the entry type specified
 186  */
 187 u32 scsi_get_new_index(scsi_index_t type)
 188 {
 189         u32 new_index;
 190
 191         BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 192
 193         spin_lock(&scsi_mib_index_lock);
 194         new_index = ++scsi_mib_index[type];
 195         spin_unlock(&scsi_mib_index_lock);
 196
 197         return new_index;
 198 }
 199
 200 void transport_subsystem_check_init(void)
 201 {
 202         int ret;
 203         static int sub_api_initialized;
 204
 205         if (sub_api_initialized)
 206                 return;
 207
 208         ret = request_module("target_core_iblock");
 209         if (ret != 0)
 210                 pr_err("Unable to load target_core_iblock\n");
 211
 212         ret = request_module("target_core_file");
 213         if (ret != 0)
 214                 pr_err("Unable to load target_core_file\n");
 215
 216         ret = request_module("target_core_pscsi");
 217         if (ret != 0)
 218                 pr_err("Unable to load target_core_pscsi\n");
 219
 220         ret = request_module("target_core_user");
 221         if (ret != 0)
 222                 pr_err("Unable to load target_core_user\n");
 223
 224         sub_api_initialized = 1;
 225 }
 226
 227 struct se_session *transport_init_session(enum target_prot_op sup_prot_ops)
 228 {
 229         struct se_session *se_sess;
 230
 231         se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 232         if (!se_sess) {
 233                 pr_err("Unable to allocate struct se_session from"
 234                                 " se_sess_cache\n");
 235                 return ERR_PTR(-ENOMEM);
 236         }
 237         INIT_LIST_HEAD(&se_sess->sess_list);
 238         INIT_LIST_HEAD(&se_sess->sess_acl_list);
 239         INIT_LIST_HEAD(&se_sess->sess_cmd_list);
 240         INIT_LIST_HEAD(&se_sess->sess_wait_list);
 241         spin_lock_init(&se_sess->sess_cmd_lock);
 242         se_sess->sup_prot_ops = sup_prot_ops;
 243
 244         return se_sess;
 245 }
 246 EXPORT_SYMBOL(transport_init_session);
 247
 248 int transport_alloc_session_tags(struct se_session *se_sess,
 249                                  unsigned int tag_num, unsigned int tag_size)
 250 {
 251         int rc;
 252
 253         se_sess->sess_cmd_map = kzalloc(tag_num * tag_size,
 254                                         GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
 255         if (!se_sess->sess_cmd_map) {
 256                 se_sess->sess_cmd_map = vzalloc(tag_num * tag_size);
 257                 if (!se_sess->sess_cmd_map) {
 258                         pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 259                         return -ENOMEM;
 260                 }
 261         }
 262
 263         rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
 264         if (rc < 0) {
 265                 pr_err("Unable to init se_sess->sess_tag_pool,"
 266                         " tag_num: %u\n", tag_num);
 267                 kvfree(se_sess->sess_cmd_map);
 268                 se_sess->sess_cmd_map = NULL;
 269                 return -ENOMEM;
 270         }
 271
 272         return 0;
 273 }
 274 EXPORT_SYMBOL(transport_alloc_session_tags);
 275
 276 struct se_session *transport_init_session_tags(unsigned int tag_num,
 277                                                unsigned int tag_size,
 278                                                enum target_prot_op sup_prot_ops)
 279 {
 280         struct se_session *se_sess;
 281         int rc;
 282
 283         if (tag_num != 0 && !tag_size) {
 284                 pr_err("init_session_tags called with percpu-ida tag_num:"
 285                        " %u, but zero tag_size\n", tag_num);
 286                 return ERR_PTR(-EINVAL);
 287         }
 288         if (!tag_num && tag_size) {
 289                 pr_err("init_session_tags called with percpu-ida tag_size:"
 290                        " %u, but zero tag_num\n", tag_size);
 291                 return ERR_PTR(-EINVAL);
 292         }
 293
 294         se_sess = transport_init_session(sup_prot_ops);
 295         if (IS_ERR(se_sess))
 296                 return se_sess;
 297
 298         rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 299         if (rc < 0) {
 300                 transport_free_session(se_sess);
 301                 return ERR_PTR(-ENOMEM);
 302         }
 303
 304         return se_sess;
 305 }
 306 EXPORT_SYMBOL(transport_init_session_tags);
 307
 308 /*
 309  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 310  */
 311 void __transport_register_session(
 312         struct se_portal_group *se_tpg,
 313         struct se_node_acl *se_nacl,
 314         struct se_session *se_sess,
 315         void *fabric_sess_ptr)
 316 {
 317         const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
 318         unsigned char buf[PR_REG_ISID_LEN];
 319
 320         se_sess->se_tpg = se_tpg;
 321         se_sess->fabric_sess_ptr = fabric_sess_ptr;
 322         /*
 323          * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 324          *
 325          * Only set for struct se_session's that will actually be moving I/O.
 326          * eg: *NOT* discovery sessions.
 327          */
 328         if (se_nacl) {
 329                 /*
 330                  *
 331                  * Determine if fabric allows for T10-PI feature bits exposed to
 332                  * initiators for device backends with !dev->dev_attrib.pi_prot_type.
 333                  *
 334                  * If so, then always save prot_type on a per se_node_acl node
 335                  * basis and re-instate the previous sess_prot_type to avoid
 336                  * disabling PI from below any previously initiator side
 337                  * registered LUNs.
 338                  */
 339                 if (se_nacl->saved_prot_type)
 340                         se_sess->sess_prot_type = se_nacl->saved_prot_type;
 341                 else if (tfo->tpg_check_prot_fabric_only)
 342                         se_sess->sess_prot_type = se_nacl->saved_prot_type =
 343                                         tfo->tpg_check_prot_fabric_only(se_tpg);
 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
 355                 spin_lock_irq(&se_nacl->nacl_sess_lock);
 356                 /*
 357                  * The se_nacl->nacl_sess pointer will be set to the
 358                  * last active I_T Nexus for each struct se_node_acl.
 359                  */
 360                 se_nacl->nacl_sess = se_sess;
 361
 362                 list_add_tail(&se_sess->sess_acl_list,
 363                               &se_nacl->acl_sess_list);
 364                 spin_unlock_irq(&se_nacl->nacl_sess_lock);
 365         }
 366         list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 367
 368         pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 369                 se_tpg->se_tpg_tfo->get_fabric_name(), se_sess->fabric_sess_ptr);
 370 }
 371 EXPORT_SYMBOL(__transport_register_session);
 372
 373 void transport_register_session(
 374         struct se_portal_group *se_tpg,
 375         struct se_node_acl *se_nacl,
 376         struct se_session *se_sess,
 377         void *fabric_sess_ptr)
 378 {
 379         unsigned long flags;
 380
 381         spin_lock_irqsave(&se_tpg->session_lock, flags);
 382         __transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 383         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 384 }
 385 EXPORT_SYMBOL(transport_register_session);
 386
 387 struct se_session *
 388 target_alloc_session(struct se_portal_group *tpg,
 389                      unsigned int tag_num, unsigned int tag_size,
 390                      enum target_prot_op prot_op,
 391                      const char *initiatorname, void *private,
 392                      int (*callback)(struct se_portal_group *,
 393                                      struct se_session *, void *))
 394 {
 395         struct se_session *sess;
 396
 397         /*
 398          * If the fabric driver is using percpu-ida based pre allocation
 399          * of I/O descriptor tags, go ahead and perform that setup now..
 400          */
 401         if (tag_num != 0)
 402                 sess = transport_init_session_tags(tag_num, tag_size, prot_op);
 403         else
 404                 sess = transport_init_session(prot_op);
 405
 406         if (IS_ERR(sess))
 407                 return sess;
 408
 409         sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
 410                                         (unsigned char *)initiatorname);
 411         if (!sess->se_node_acl) {
 412                 transport_free_session(sess);
 413                 return ERR_PTR(-EACCES);
 414         }
 415         /*
 416          * Go ahead and perform any remaining fabric setup that is
 417          * required before transport_register_session().
 418          */
 419         if (callback != NULL) {
 420                 int rc = callback(tpg, sess, private);
 421                 if (rc) {
 422                         transport_free_session(sess);
 423                         return ERR_PTR(rc);
 424                 }
 425         }
 426
 427         transport_register_session(tpg, sess->se_node_acl, sess, private);
 428         return sess;
 429 }
 430 EXPORT_SYMBOL(target_alloc_session);
 431
 432 ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
 433 {
 434         struct se_session *se_sess;
 435         ssize_t len = 0;
 436
 437         spin_lock_bh(&se_tpg->session_lock);
 438         list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
 439                 if (!se_sess->se_node_acl)
 440                         continue;
 441                 if (!se_sess->se_node_acl->dynamic_node_acl)
 442                         continue;
 443                 if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
 444                         break;
 445
 446                 len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
 447                                 se_sess->se_node_acl->initiatorname);
 448                 len += 1; /* Include NULL terminator */
 449         }
 450         spin_unlock_bh(&se_tpg->session_lock);
 451
 452         return len;
 453 }
 454 EXPORT_SYMBOL(target_show_dynamic_sessions);
 455
 456 static void target_complete_nacl(struct kref *kref)
 457 {
 458         struct se_node_acl *nacl = container_of(kref,
 459                                 struct se_node_acl, acl_kref);
 460
 461         complete(&nacl->acl_free_comp);
 462 }
 463
 464 void target_put_nacl(struct se_node_acl *nacl)
 465 {
 466         kref_put(&nacl->acl_kref, target_complete_nacl);
 467 }
 468 EXPORT_SYMBOL(target_put_nacl);
 469
 470 void transport_deregister_session_configfs(struct se_session *se_sess)
 471 {
 472         struct se_node_acl *se_nacl;
 473         unsigned long flags;
 474         /*
 475          * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 476          */
 477         se_nacl = se_sess->se_node_acl;
 478         if (se_nacl) {
 479                 spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 480                 if (!list_empty(&se_sess->sess_acl_list))
 481                         list_del_init(&se_sess->sess_acl_list);
 482                 /*
 483                  * If the session list is empty, then clear the pointer.
 484                  * Otherwise, set the struct se_session pointer from the tail
 485                  * element of the per struct se_node_acl active session list.
 486                  */
 487                 if (list_empty(&se_nacl->acl_sess_list))
 488                         se_nacl->nacl_sess = NULL;
 489                 else {
 490                         se_nacl->nacl_sess = container_of(
 491                                         se_nacl->acl_sess_list.prev,
 492                                         struct se_session, sess_acl_list);
 493                 }
 494                 spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 495         }
 496 }
 497 EXPORT_SYMBOL(transport_deregister_session_configfs);
 498
 499 void transport_free_session(struct se_session *se_sess)
 500 {
 501         struct se_node_acl *se_nacl = se_sess->se_node_acl;
 502         /*
 503          * Drop the se_node_acl->nacl_kref obtained from within
 504          * core_tpg_get_initiator_node_acl().
 505          */
 506         if (se_nacl) {
 507                 se_sess->se_node_acl = NULL;
 508                 target_put_nacl(se_nacl);
 509         }
 510         if (se_sess->sess_cmd_map) {
 511                 percpu_ida_destroy(&se_sess->sess_tag_pool);
 512                 kvfree(se_sess->sess_cmd_map);
 513         }
 514         kmem_cache_free(se_sess_cache, se_sess);
 515 }
 516 EXPORT_SYMBOL(transport_free_session);
 517
 518 void transport_deregister_session(struct se_session *se_sess)
 519 {
 520         struct se_portal_group *se_tpg = se_sess->se_tpg;
 521         const struct target_core_fabric_ops *se_tfo;
 522         struct se_node_acl *se_nacl;
 523         unsigned long flags;
 524         bool drop_nacl = false;
 525
 526         if (!se_tpg) {
 527                 transport_free_session(se_sess);
 528                 return;
 529         }
 530         se_tfo = se_tpg->se_tpg_tfo;
 531
 532         spin_lock_irqsave(&se_tpg->session_lock, flags);
 533         list_del(&se_sess->sess_list);
 534         se_sess->se_tpg = NULL;
 535         se_sess->fabric_sess_ptr = NULL;
 536         spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 537
 538         /*
 539          * Determine if we need to do extra work for this initiator node's
 540          * struct se_node_acl if it had been previously dynamically generated.
 541          */
 542         se_nacl = se_sess->se_node_acl;
 543
 544         mutex_lock(&se_tpg->acl_node_mutex);
 545         if (se_nacl && se_nacl->dynamic_node_acl) {
 546                 if (!se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 547                         list_del(&se_nacl->acl_list);
 548                         drop_nacl = true;
 549                 }
 550         }
 551         mutex_unlock(&se_tpg->acl_node_mutex);
 552
 553         if (drop_nacl) {
 554                 core_tpg_wait_for_nacl_pr_ref(se_nacl);
 555                 core_free_device_list_for_node(se_nacl, se_tpg);
 556                 se_sess->se_node_acl = NULL;
 557                 kfree(se_nacl);
 558         }
 559         pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 560                 se_tpg->se_tpg_tfo->get_fabric_name());
 561         /*
 562          * If last kref is dropping now for an explicit NodeACL, awake sleeping
 563          * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 564          * removal context from within transport_free_session() code.
 565          */
 566
 567         transport_free_session(se_sess);
 568 }
 569 EXPORT_SYMBOL(transport_deregister_session);
 570
 571 static void target_remove_from_state_list(struct se_cmd *cmd)
 572 {
 573         struct se_device *dev = cmd->se_dev;
 574         unsigned long flags;
 575
 576         if (!dev)
 577                 return;
 578
 579         if (cmd->transport_state & CMD_T_BUSY)
 580                 return;
 581
 582         spin_lock_irqsave(&dev->execute_task_lock, flags);
 583         if (cmd->state_active) {
 584                 list_del(&cmd->state_list);
 585                 cmd->state_active = false;
 586         }
 587         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 588 }
 589
 590 static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists,
 591                                     bool write_pending)
 592 {
 593         unsigned long flags;
 594
 595         if (remove_from_lists) {
 596                 target_remove_from_state_list(cmd);
 597
 598                 /*
 599                  * Clear struct se_cmd->se_lun before the handoff to FE.
 600                  */
 601                 cmd->se_lun = NULL;
 602         }
 603
 604         spin_lock_irqsave(&cmd->t_state_lock, flags);
 605         if (write_pending)
 606                 cmd->t_state = TRANSPORT_WRITE_PENDING;
 607
 608         /*
 609          * Determine if frontend context caller is requesting the stopping of
 610          * this command for frontend exceptions.
 611          */
 612         if (cmd->transport_state & CMD_T_STOP) {
 613                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
 614                         __func__, __LINE__, cmd->tag);
 615
 616                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 617
 618                 complete_all(&cmd->t_transport_stop_comp);
 619                 return 1;
 620         }
 621
 622         cmd->transport_state &= ~CMD_T_ACTIVE;
 623         if (remove_from_lists) {
 624                 /*
 625                  * Some fabric modules like tcm_loop can release
 626                  * their internally allocated I/O reference now and
 627                  * struct se_cmd now.
 628                  *
 629                  * Fabric modules are expected to return '1' here if the
 630                  * se_cmd being passed is released at this point,
 631                  * or zero if not being released.
 632                  */
 633                 if (cmd->se_tfo->check_stop_free != NULL) {
 634                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 635                         return cmd->se_tfo->check_stop_free(cmd);
 636                 }
 637         }
 638
 639         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 640         return 0;
 641 }
 642
 643 static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 644 {
 645         return transport_cmd_check_stop(cmd, true, false);
 646 }
 647
 648 static void transport_lun_remove_cmd(struct se_cmd *cmd)
 649 {
 650         struct se_lun *lun = cmd->se_lun;
 651
 652         if (!lun)
 653                 return;
 654
 655         if (cmpxchg(&cmd->lun_ref_active, true, false))
 656                 percpu_ref_put(&lun->lun_ref);
 657 }
 658
 659 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 660 {
 661         bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF);
 662
 663         if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
 664                 transport_lun_remove_cmd(cmd);
 665         /*
 666          * Allow the fabric driver to unmap any resources before
 667          * releasing the descriptor via TFO->release_cmd()
 668          */
 669         if (remove)
 670                 cmd->se_tfo->aborted_task(cmd);
 671
 672         if (transport_cmd_check_stop_to_fabric(cmd))
 673                 return;
 674         if (remove && ack_kref)
 675                 transport_put_cmd(cmd);
 676 }
 677
 678 static void target_complete_failure_work(struct work_struct *work)
 679 {
 680         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 681
 682         transport_generic_request_failure(cmd,
 683                         TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
 684 }
 685
 686 /*
 687  * Used when asking transport to copy Sense Data from the underlying
 688  * Linux/SCSI struct scsi_cmnd
 689  */
 690 static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 691 {
 692         struct se_device *dev = cmd->se_dev;
 693
 694         WARN_ON(!cmd->se_lun);
 695
 696         if (!dev)
 697                 return NULL;
 698
 699         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 700                 return NULL;
 701
 702         cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 703
 704         pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 705                 dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 706         return cmd->sense_buffer;
 707 }
 708
 709 void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 710 {
 711         struct se_device *dev = cmd->se_dev;
 712         int success = scsi_status == GOOD;
 713         unsigned long flags;
 714
 715         cmd->scsi_status = scsi_status;
 716
 717
 718         spin_lock_irqsave(&cmd->t_state_lock, flags);
 719         cmd->transport_state &= ~CMD_T_BUSY;
 720
 721         if (dev && dev->transport->transport_complete) {
 722                 dev->transport->transport_complete(cmd,
 723                                 cmd->t_data_sg,
 724                                 transport_get_sense_buffer(cmd));
 725                 if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 726                         success = 1;
 727         }
 728
 729         /*
 730          * Check for case where an explicit ABORT_TASK has been received
 731          * and transport_wait_for_tasks() will be waiting for completion..
 732          */
 733         if (cmd->transport_state & CMD_T_ABORTED ||
 734             cmd->transport_state & CMD_T_STOP) {
 735                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 736                 complete_all(&cmd->t_transport_stop_comp);
 737                 return;
 738         } else if (!success) {
 739                 INIT_WORK(&cmd->work, target_complete_failure_work);
 740         } else {
 741                 INIT_WORK(&cmd->work, target_complete_ok_work);
 742         }
 743
 744         cmd->t_state = TRANSPORT_COMPLETE;
 745         cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 746         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 747
 748         if (cmd->se_cmd_flags & SCF_USE_CPUID)
 749                 queue_work_on(cmd->cpuid, target_completion_wq, &cmd->work);
 750         else
 751                 queue_work(target_completion_wq, &cmd->work);
 752 }
 753 EXPORT_SYMBOL(target_complete_cmd);
 754
 755 void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 756 {
 757         if (scsi_status == SAM_STAT_GOOD && length < cmd->data_length) {
 758                 if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 759                         cmd->residual_count += cmd->data_length - length;
 760                 } else {
 761                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
 762                         cmd->residual_count = cmd->data_length - length;
 763                 }
 764
 765                 cmd->data_length = length;
 766         }
 767
 768         target_complete_cmd(cmd, scsi_status);
 769 }
 770 EXPORT_SYMBOL(target_complete_cmd_with_length);
 771
 772 static void target_add_to_state_list(struct se_cmd *cmd)
 773 {
 774         struct se_device *dev = cmd->se_dev;
 775         unsigned long flags;
 776
 777         spin_lock_irqsave(&dev->execute_task_lock, flags);
 778         if (!cmd->state_active) {
 779                 list_add_tail(&cmd->state_list, &dev->state_list);
 780                 cmd->state_active = true;
 781         }
 782         spin_unlock_irqrestore(&dev->execute_task_lock, flags);
 783 }
 784
 785 /*
 786  * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 787  */
 788 static void transport_write_pending_qf(struct se_cmd *cmd);
 789 static void transport_complete_qf(struct se_cmd *cmd);
 790
 791 void target_qf_do_work(struct work_struct *work)
 792 {
 793         struct se_device *dev = container_of(work, struct se_device,
 794                                         qf_work_queue);
 795         LIST_HEAD(qf_cmd_list);
 796         struct se_cmd *cmd, *cmd_tmp;
 797
 798         spin_lock_irq(&dev->qf_cmd_lock);
 799         list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
 800         spin_unlock_irq(&dev->qf_cmd_lock);
 801
 802         list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
 803                 list_del(&cmd->se_qf_node);
 804                 atomic_dec_mb(&dev->dev_qf_count);
 805
 806                 pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
 807                         " context: %s\n", cmd->se_tfo->get_fabric_name(), cmd,
 808                         (cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
 809                         (cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
 810                         : "UNKNOWN");
 811
 812                 if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
 813                         transport_write_pending_qf(cmd);
 814                 else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK)
 815                         transport_complete_qf(cmd);
 816         }
 817 }
 818
 819 unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
 820 {
 821         switch (cmd->data_direction) {
 822         case DMA_NONE:
 823                 return "NONE";
 824         case DMA_FROM_DEVICE:
 825                 return "READ";
 826         case DMA_TO_DEVICE:
 827                 return "WRITE";
 828         case DMA_BIDIRECTIONAL:
 829                 return "BIDI";
 830         default:
 831                 break;
 832         }
 833
 834         return "UNKNOWN";
 835 }
 836
 837 void transport_dump_dev_state(
 838         struct se_device *dev,
 839         char *b,
 840         int *bl)
 841 {
 842         *bl += sprintf(b + *bl, "Status: ");
 843         if (dev->export_count)
 844                 *bl += sprintf(b + *bl, "ACTIVATED");
 845         else
 846                 *bl += sprintf(b + *bl, "DEACTIVATED");
 847
 848         *bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
 849         *bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
 850                 dev->dev_attrib.block_size,
 851                 dev->dev_attrib.hw_max_sectors);
 852         *bl += sprintf(b + *bl, "        ");
 853 }
 854
 855 void transport_dump_vpd_proto_id(
 856         struct t10_vpd *vpd,
 857         unsigned char *p_buf,
 858         int p_buf_len)
 859 {
 860         unsigned char buf[VPD_TMP_BUF_SIZE];
 861         int len;
 862
 863         memset(buf, 0, VPD_TMP_BUF_SIZE);
 864         len = sprintf(buf, "T10 VPD Protocol Identifier: ");
 865
 866         switch (vpd->protocol_identifier) {
 867         case 0x00:
 868                 sprintf(buf+len, "Fibre Channel\n");
 869                 break;
 870         case 0x10:
 871                 sprintf(buf+len, "Parallel SCSI\n");
 872                 break;
 873         case 0x20:
 874                 sprintf(buf+len, "SSA\n");
 875                 break;
 876         case 0x30:
 877                 sprintf(buf+len, "IEEE 1394\n");
 878                 break;
 879         case 0x40:
 880                 sprintf(buf+len, "SCSI Remote Direct Memory Access"
 881                                 " Protocol\n");
 882                 break;
 883         case 0x50:
 884                 sprintf(buf+len, "Internet SCSI (iSCSI)\n");
 885                 break;
 886         case 0x60:
 887                 sprintf(buf+len, "SAS Serial SCSI Protocol\n");
 888                 break;
 889         case 0x70:
 890                 sprintf(buf+len, "Automation/Drive Interface Transport"
 891                                 " Protocol\n");
 892                 break;
 893         case 0x80:
 894                 sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
 895                 break;
 896         default:
 897                 sprintf(buf+len, "Unknown 0x%02x\n",
 898                                 vpd->protocol_identifier);
 899                 break;
 900         }
 901
 902         if (p_buf)
 903                 strncpy(p_buf, buf, p_buf_len);
 904         else
 905                 pr_debug("%s", buf);
 906 }
 907
 908 void
 909 transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
 910 {
 911         /*
 912          * Check if the Protocol Identifier Valid (PIV) bit is set..
 913          *
 914          * from spc3r23.pdf section 7.5.1
 915          */
 916          if (page_83[1] & 0x80) {
 917                 vpd->protocol_identifier = (page_83[0] & 0xf0);
 918                 vpd->protocol_identifier_set = 1;
 919                 transport_dump_vpd_proto_id(vpd, NULL, 0);
 920         }
 921 }
 922 EXPORT_SYMBOL(transport_set_vpd_proto_id);
 923
 924 int transport_dump_vpd_assoc(
 925         struct t10_vpd *vpd,
 926         unsigned char *p_buf,
 927         int p_buf_len)
 928 {
 929         unsigned char buf[VPD_TMP_BUF_SIZE];
 930         int ret = 0;
 931         int len;
 932
 933         memset(buf, 0, VPD_TMP_BUF_SIZE);
 934         len = sprintf(buf, "T10 VPD Identifier Association: ");
 935
 936         switch (vpd->association) {
 937         case 0x00:
 938                 sprintf(buf+len, "addressed logical unit\n");
 939                 break;
 940         case 0x10:
 941                 sprintf(buf+len, "target port\n");
 942                 break;
 943         case 0x20:
 944                 sprintf(buf+len, "SCSI target device\n");
 945                 break;
 946         default:
 947                 sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
 948                 ret = -EINVAL;
 949                 break;
 950         }
 951
 952         if (p_buf)
 953                 strncpy(p_buf, buf, p_buf_len);
 954         else
 955                 pr_debug("%s", buf);
 956
 957         return ret;
 958 }
 959
 960 int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
 961 {
 962         /*
 963          * The VPD identification association..
 964          *
 965          * from spc3r23.pdf Section 7.6.3.1 Table 297
 966          */
 967         vpd->association = (page_83[1] & 0x30);
 968         return transport_dump_vpd_assoc(vpd, NULL, 0);
 969 }
 970 EXPORT_SYMBOL(transport_set_vpd_assoc);
 971
 972 int transport_dump_vpd_ident_type(
 973         struct t10_vpd *vpd,
 974         unsigned char *p_buf,
 975         int p_buf_len)
 976 {
 977         unsigned char buf[VPD_TMP_BUF_SIZE];
 978         int ret = 0;
 979         int len;
 980
 981         memset(buf, 0, VPD_TMP_BUF_SIZE);
 982         len = sprintf(buf, "T10 VPD Identifier Type: ");
 983
 984         switch (vpd->device_identifier_type) {
 985         case 0x00:
 986                 sprintf(buf+len, "Vendor specific\n");
 987                 break;
 988         case 0x01:
 989                 sprintf(buf+len, "T10 Vendor ID based\n");
 990                 break;
 991         case 0x02:
 992                 sprintf(buf+len, "EUI-64 based\n");
 993                 break;
 994         case 0x03:
 995                 sprintf(buf+len, "NAA\n");
 996                 break;
 997         case 0x04:
 998                 sprintf(buf+len, "Relative target port identifier\n");
 999                 break;
1000         case 0x08:
1001                 sprintf(buf+len, "SCSI name string\n");
1002                 break;
1003         default:
1004                 sprintf(buf+len, "Unsupported: 0x%02x\n",
1005                                 vpd->device_identifier_type);
1006                 ret = -EINVAL;
1007                 break;
1008         }
1009
1010         if (p_buf) {
1011                 if (p_buf_len < strlen(buf)+1)
1012                         return -EINVAL;
1013                 strncpy(p_buf, buf, p_buf_len);
1014         } else {
1015                 pr_debug("%s", buf);
1016         }
1017
1018         return ret;
1019 }
1020
1021 int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1022 {
1023         /*
1024          * The VPD identifier type..
1025          *
1026          * from spc3r23.pdf Section 7.6.3.1 Table 298
1027          */
1028         vpd->device_identifier_type = (page_83[1] & 0x0f);
1029         return transport_dump_vpd_ident_type(vpd, NULL, 0);
1030 }
1031 EXPORT_SYMBOL(transport_set_vpd_ident_type);
1032
1033 int transport_dump_vpd_ident(
1034         struct t10_vpd *vpd,
1035         unsigned char *p_buf,
1036         int p_buf_len)
1037 {
1038         unsigned char buf[VPD_TMP_BUF_SIZE];
1039         int ret = 0;
1040
1041         memset(buf, 0, VPD_TMP_BUF_SIZE);
1042
1043         switch (vpd->device_identifier_code_set) {
1044         case 0x01: /* Binary */
1045                 snprintf(buf, sizeof(buf),
1046                         "T10 VPD Binary Device Identifier: %s\n",
1047                         &vpd->device_identifier[0]);
1048                 break;
1049         case 0x02: /* ASCII */
1050                 snprintf(buf, sizeof(buf),
1051                         "T10 VPD ASCII Device Identifier: %s\n",
1052                         &vpd->device_identifier[0]);
1053                 break;
1054         case 0x03: /* UTF-8 */
1055                 snprintf(buf, sizeof(buf),
1056                         "T10 VPD UTF-8 Device Identifier: %s\n",
1057                         &vpd->device_identifier[0]);
1058                 break;
1059         default:
1060                 sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1061                         " 0x%02x", vpd->device_identifier_code_set);
1062                 ret = -EINVAL;
1063                 break;
1064         }
1065
1066         if (p_buf)
1067                 strncpy(p_buf, buf, p_buf_len);
1068         else
1069                 pr_debug("%s", buf);
1070
1071         return ret;
1072 }
1073
1074 int
1075 transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1076 {
1077         static const char hex_str[] = "0123456789abcdef";
1078         int j = 0, i = 4; /* offset to start of the identifier */
1079
1080         /*
1081          * The VPD Code Set (encoding)
1082          *
1083          * from spc3r23.pdf Section 7.6.3.1 Table 296
1084          */
1085         vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1086         switch (vpd->device_identifier_code_set) {
1087         case 0x01: /* Binary */
1088                 vpd->device_identifier[j++] =
1089                                 hex_str[vpd->device_identifier_type];
1090                 while (i < (4 + page_83[3])) {
1091                         vpd->device_identifier[j++] =
1092                                 hex_str[(page_83[i] & 0xf0) >> 4];
1093                         vpd->device_identifier[j++] =
1094                                 hex_str[page_83[i] & 0x0f];
1095                         i++;
1096                 }
1097                 break;
1098         case 0x02: /* ASCII */
1099         case 0x03: /* UTF-8 */
1100                 while (i < (4 + page_83[3]))
1101                         vpd->device_identifier[j++] = page_83[i++];
1102                 break;
1103         default:
1104                 break;
1105         }
1106
1107         return transport_dump_vpd_ident(vpd, NULL, 0);
1108 }
1109 EXPORT_SYMBOL(transport_set_vpd_ident);
1110
1111 static sense_reason_t
1112 target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1113                                unsigned int size)
1114 {
1115         u32 mtl;
1116
1117         if (!cmd->se_tfo->max_data_sg_nents)
1118                 return TCM_NO_SENSE;
1119         /*
1120          * Check if fabric enforced maximum SGL entries per I/O descriptor
1121          * exceeds se_cmd->data_length.  If true, set SCF_UNDERFLOW_BIT +
1122          * residual_count and reduce original cmd->data_length to maximum
1123          * length based on single PAGE_SIZE entry scatter-lists.
1124          */
1125         mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1126         if (cmd->data_length > mtl) {
1127                 /*
1128                  * If an existing CDB overflow is present, calculate new residual
1129                  * based on CDB size minus fabric maximum transfer length.
1130                  *
1131                  * If an existing CDB underflow is present, calculate new residual
1132                  * based on original cmd->data_length minus fabric maximum transfer
1133                  * length.
1134                  *
1135                  * Otherwise, set the underflow residual based on cmd->data_length
1136                  * minus fabric maximum transfer length.
1137                  */
1138                 if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1139                         cmd->residual_count = (size - mtl);
1140                 } else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1141                         u32 orig_dl = size + cmd->residual_count;
1142                         cmd->residual_count = (orig_dl - mtl);
1143                 } else {
1144                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1145                         cmd->residual_count = (cmd->data_length - mtl);
1146                 }
1147                 cmd->data_length = mtl;
1148                 /*
1149                  * Reset sbc_check_prot() calculated protection payload
1150                  * length based upon the new smaller MTL.
1151                  */
1152                 if (cmd->prot_length) {
1153                         u32 sectors = (mtl / dev->dev_attrib.block_size);
1154                         cmd->prot_length = dev->prot_length * sectors;
1155                 }
1156         }
1157         return TCM_NO_SENSE;
1158 }
1159
1160 sense_reason_t
1161 target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1162 {
1163         struct se_device *dev = cmd->se_dev;
1164
1165         if (cmd->unknown_data_length) {
1166                 cmd->data_length = size;
1167         } else if (size != cmd->data_length) {
1168                 pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
1169                         " %u does not match SCSI CDB Length: %u for SAM Opcode:"
1170                         " 0x%02x\n", cmd->se_tfo->get_fabric_name(),
1171                                 cmd->data_length, size, cmd->t_task_cdb[0]);
1172
1173                 if (cmd->data_direction == DMA_TO_DEVICE &&
1174                     cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1175                         pr_err("Rejecting underflow/overflow WRITE data\n");
1176                         return TCM_INVALID_CDB_FIELD;
1177                 }
1178                 /*
1179                  * Reject READ_* or WRITE_* with overflow/underflow for
1180                  * type SCF_SCSI_DATA_CDB.
1181                  */
1182                 if (dev->dev_attrib.block_size != 512)  {
1183                         pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
1184                                 " CDB on non 512-byte sector setup subsystem"
1185                                 " plugin: %s\n", dev->transport->name);
1186                         /* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
1187                         return TCM_INVALID_CDB_FIELD;
1188                 }
1189                 /*
1190                  * For the overflow case keep the existing fabric provided
1191                  * ->data_length.  Otherwise for the underflow case, reset
1192                  * ->data_length to the smaller SCSI expected data transfer
1193                  * length.
1194                  */
1195                 if (size > cmd->data_length) {
1196                         cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1197                         cmd->residual_count = (size - cmd->data_length);
1198                 } else {
1199                         cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1200                         cmd->residual_count = (cmd->data_length - size);
1201                         cmd->data_length = size;
1202                 }
1203         }
1204
1205         return target_check_max_data_sg_nents(cmd, dev, size);
1206
1207 }
1208
1209 /*
1210  * Used by fabric modules containing a local struct se_cmd within their
1211  * fabric dependent per I/O descriptor.
1212  *
1213  * Preserves the value of @cmd->tag.
1214  */
1215 void transport_init_se_cmd(
1216         struct se_cmd *cmd,
1217         const struct target_core_fabric_ops *tfo,
1218         struct se_session *se_sess,
1219         u32 data_length,
1220         int data_direction,
1221         int task_attr,
1222         unsigned char *sense_buffer)
1223 {
1224         INIT_LIST_HEAD(&cmd->se_delayed_node);
1225         INIT_LIST_HEAD(&cmd->se_qf_node);
1226         INIT_LIST_HEAD(&cmd->se_cmd_list);
1227         INIT_LIST_HEAD(&cmd->state_list);
1228         init_completion(&cmd->t_transport_stop_comp);
1229         init_completion(&cmd->cmd_wait_comp);
1230         spin_lock_init(&cmd->t_state_lock);
1231         kref_init(&cmd->cmd_kref);
1232         cmd->transport_state = CMD_T_DEV_ACTIVE;
1233
1234         cmd->se_tfo = tfo;
1235         cmd->se_sess = se_sess;
1236         cmd->data_length = data_length;
1237         cmd->data_direction = data_direction;
1238         cmd->sam_task_attr = task_attr;
1239         cmd->sense_buffer = sense_buffer;
1240
1241         cmd->state_active = false;
1242 }
1243 EXPORT_SYMBOL(transport_init_se_cmd);
1244
1245 static sense_reason_t
1246 transport_check_alloc_task_attr(struct se_cmd *cmd)
1247 {
1248         struct se_device *dev = cmd->se_dev;
1249
1250         /*
1251          * Check if SAM Task Attribute emulation is enabled for this
1252          * struct se_device storage object
1253          */
1254         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1255                 return 0;
1256
1257         if (cmd->sam_task_attr == TCM_ACA_TAG) {
1258                 pr_debug("SAM Task Attribute ACA"
1259                         " emulation is not supported\n");
1260                 return TCM_INVALID_CDB_FIELD;
1261         }
1262
1263         return 0;
1264 }
1265
1266 sense_reason_t
1267 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
1268 {
1269         struct se_device *dev = cmd->se_dev;
1270         sense_reason_t ret;
1271
1272         /*
1273          * Ensure that the received CDB is less than the max (252 + 8) bytes
1274          * for VARIABLE_LENGTH_CMD
1275          */
1276         if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1277                 pr_err("Received SCSI CDB with command_size: %d that"
1278                         " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1279                         scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1280                 return TCM_INVALID_CDB_FIELD;
1281         }
1282         /*
1283          * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1284          * allocate the additional extended CDB buffer now..  Otherwise
1285          * setup the pointer from __t_task_cdb to t_task_cdb.
1286          */
1287         if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1288                 cmd->t_task_cdb = kzalloc(scsi_command_size(cdb),
1289                                                 GFP_KERNEL);
1290                 if (!cmd->t_task_cdb) {
1291                         pr_err("Unable to allocate cmd->t_task_cdb"
1292                                 " %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1293                                 scsi_command_size(cdb),
1294                                 (unsigned long)sizeof(cmd->__t_task_cdb));
1295                         return TCM_OUT_OF_RESOURCES;
1296                 }
1297         } else
1298                 cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1299         /*
1300          * Copy the original CDB into cmd->
1301          */
1302         memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1303
1304         trace_target_sequencer_start(cmd);
1305
1306         /*
1307          * Check for an existing UNIT ATTENTION condition
1308          */
1309         ret = target_scsi3_ua_check(cmd);
1310         if (ret)
1311                 return ret;
1312
1313         ret = target_alua_state_check(cmd);
1314         if (ret)
1315                 return ret;
1316
1317         ret = target_check_reservation(cmd);
1318         if (ret) {
1319                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1320                 return ret;
1321         }
1322
1323         ret = dev->transport->parse_cdb(cmd);
1324         if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1325                 pr_warn_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1326                                     cmd->se_tfo->get_fabric_name(),
1327                                     cmd->se_sess->se_node_acl->initiatorname,
1328                                     cmd->t_task_cdb[0]);
1329         if (ret)
1330                 return ret;
1331
1332         ret = transport_check_alloc_task_attr(cmd);
1333         if (ret)
1334                 return ret;
1335
1336         cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1337         atomic_long_inc(&cmd->se_lun->lun_stats.cmd_pdus);
1338         return 0;
1339 }
1340 EXPORT_SYMBOL(target_setup_cmd_from_cdb);
1341
1342 /*
1343  * Used by fabric module frontends to queue tasks directly.
1344  * May only be used from process context.
1345  */
1346 int transport_handle_cdb_direct(
1347         struct se_cmd *cmd)
1348 {
1349         sense_reason_t ret;
1350
1351         if (!cmd->se_lun) {
1352                 dump_stack();
1353                 pr_err("cmd->se_lun is NULL\n");
1354                 return -EINVAL;
1355         }
1356         if (in_interrupt()) {
1357                 dump_stack();
1358                 pr_err("transport_generic_handle_cdb cannot be called"
1359                                 " from interrupt context\n");
1360                 return -EINVAL;
1361         }
1362         /*
1363          * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1364          * outstanding descriptors are handled correctly during shutdown via
1365          * transport_wait_for_tasks()
1366          *
1367          * Also, we don't take cmd->t_state_lock here as we only expect
1368          * this to be called for initial descriptor submission.
1369          */
1370         cmd->t_state = TRANSPORT_NEW_CMD;
1371         cmd->transport_state |= CMD_T_ACTIVE;
1372
1373         /*
1374          * transport_generic_new_cmd() is already handling QUEUE_FULL,
1375          * so follow TRANSPORT_NEW_CMD processing thread context usage
1376          * and call transport_generic_request_failure() if necessary..
1377          */
1378         ret = transport_generic_new_cmd(cmd);
1379         if (ret)
1380                 transport_generic_request_failure(cmd, ret);
1381         return 0;
1382 }
1383 EXPORT_SYMBOL(transport_handle_cdb_direct);
1384
1385 sense_reason_t
1386 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1387                 u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1388 {
1389         if (!sgl || !sgl_count)
1390                 return 0;
1391
1392         /*
1393          * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1394          * scatterlists already have been set to follow what the fabric
1395          * passes for the original expected data transfer length.
1396          */
1397         if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1398                 pr_warn("Rejecting SCSI DATA overflow for fabric using"
1399                         " SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1400                 return TCM_INVALID_CDB_FIELD;
1401         }
1402
1403         cmd->t_data_sg = sgl;
1404         cmd->t_data_nents = sgl_count;
1405         cmd->t_bidi_data_sg = sgl_bidi;
1406         cmd->t_bidi_data_nents = sgl_bidi_count;
1407
1408         cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1409         return 0;
1410 }
1411
1412 /*
1413  * target_submit_cmd_map_sgls - lookup unpacked lun and submit uninitialized
1414  *                       se_cmd + use pre-allocated SGL memory.
1415  *
1416  * @se_cmd: command descriptor to submit
1417  * @se_sess: associated se_sess for endpoint
1418  * @cdb: pointer to SCSI CDB
1419  * @sense: pointer to SCSI sense buffer
1420  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1421  * @data_length: fabric expected data transfer length
1422  * @task_addr: SAM task attribute
1423  * @data_dir: DMA data direction
1424  * @flags: flags for command submission from target_sc_flags_tables
1425  * @sgl: struct scatterlist memory for unidirectional mapping
1426  * @sgl_count: scatterlist count for unidirectional mapping
1427  * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1428  * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1429  * @sgl_prot: struct scatterlist memory protection information
1430  * @sgl_prot_count: scatterlist count for protection information
1431  *
1432  * Task tags are supported if the caller has set @se_cmd->tag.
1433  *
1434  * Returns non zero to signal active I/O shutdown failure.  All other
1435  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1436  * but still return zero here.
1437  *
1438  * This may only be called from process context, and also currently
1439  * assumes internal allocation of fabric payload buffer by target-core.
1440  */
1441 int target_submit_cmd_map_sgls(struct se_cmd *se_cmd, struct se_session *se_sess,
1442                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1443                 u32 data_length, int task_attr, int data_dir, int flags,
1444                 struct scatterlist *sgl, u32 sgl_count,
1445                 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1446                 struct scatterlist *sgl_prot, u32 sgl_prot_count)
1447 {
1448         struct se_portal_group *se_tpg;
1449         sense_reason_t rc;
1450         int ret;
1451
1452         se_tpg = se_sess->se_tpg;
1453         BUG_ON(!se_tpg);
1454         BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1455         BUG_ON(in_interrupt());
1456         /*
1457          * Initialize se_cmd for target operation.  From this point
1458          * exceptions are handled by sending exception status via
1459          * target_core_fabric_ops->queue_status() callback
1460          */
1461         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1462                                 data_length, data_dir, task_attr, sense);
1463
1464         if (flags & TARGET_SCF_USE_CPUID)
1465                 se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1466         else
1467                 se_cmd->cpuid = WORK_CPU_UNBOUND;
1468
1469         if (flags & TARGET_SCF_UNKNOWN_SIZE)
1470                 se_cmd->unknown_data_length = 1;
1471         /*
1472          * Obtain struct se_cmd->cmd_kref reference and add new cmd to
1473          * se_sess->sess_cmd_list.  A second kref_get here is necessary
1474          * for fabrics using TARGET_SCF_ACK_KREF that expect a second
1475          * kref_put() to happen during fabric packet acknowledgement.
1476          */
1477         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1478         if (ret)
1479                 return ret;
1480         /*
1481          * Signal bidirectional data payloads to target-core
1482          */
1483         if (flags & TARGET_SCF_BIDI_OP)
1484                 se_cmd->se_cmd_flags |= SCF_BIDI;
1485         /*
1486          * Locate se_lun pointer and attach it to struct se_cmd
1487          */
1488         rc = transport_lookup_cmd_lun(se_cmd, unpacked_lun);
1489         if (rc) {
1490                 transport_send_check_condition_and_sense(se_cmd, rc, 0);
1491                 target_put_sess_cmd(se_cmd);
1492                 return 0;
1493         }
1494
1495         rc = target_setup_cmd_from_cdb(se_cmd, cdb);
1496         if (rc != 0) {
1497                 transport_generic_request_failure(se_cmd, rc);
1498                 return 0;
1499         }
1500
1501         /*
1502          * Save pointers for SGLs containing protection information,
1503          * if present.
1504          */
1505         if (sgl_prot_count) {
1506                 se_cmd->t_prot_sg = sgl_prot;
1507                 se_cmd->t_prot_nents = sgl_prot_count;
1508                 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1509         }
1510
1511         /*
1512          * When a non zero sgl_count has been passed perform SGL passthrough
1513          * mapping for pre-allocated fabric memory instead of having target
1514          * core perform an internal SGL allocation..
1515          */
1516         if (sgl_count != 0) {
1517                 BUG_ON(!sgl);
1518
1519                 /*
1520                  * A work-around for tcm_loop as some userspace code via
1521                  * scsi-generic do not memset their associated read buffers,
1522                  * so go ahead and do that here for type non-data CDBs.  Also
1523                  * note that this is currently guaranteed to be a single SGL
1524                  * for this case by target core in target_setup_cmd_from_cdb()
1525                  * -> transport_generic_cmd_sequencer().
1526                  */
1527                 if (!(se_cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1528                      se_cmd->data_direction == DMA_FROM_DEVICE) {
1529                         unsigned char *buf = NULL;
1530
1531                         if (sgl)
1532                                 buf = kmap(sg_page(sgl)) + sgl->offset;
1533
1534                         if (buf) {
1535                                 memset(buf, 0, sgl->length);
1536                                 kunmap(sg_page(sgl));
1537                         }
1538                 }
1539
1540                 rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1541                                 sgl_bidi, sgl_bidi_count);
1542                 if (rc != 0) {
1543                         transport_generic_request_failure(se_cmd, rc);
1544                         return 0;
1545                 }
1546         }
1547
1548         /*
1549          * Check if we need to delay processing because of ALUA
1550          * Active/NonOptimized primary access state..
1551          */
1552         core_alua_check_nonop_delay(se_cmd);
1553
1554         transport_handle_cdb_direct(se_cmd);
1555         return 0;
1556 }
1557 EXPORT_SYMBOL(target_submit_cmd_map_sgls);
1558
1559 /*
1560  * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1561  *
1562  * @se_cmd: command descriptor to submit
1563  * @se_sess: associated se_sess for endpoint
1564  * @cdb: pointer to SCSI CDB
1565  * @sense: pointer to SCSI sense buffer
1566  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1567  * @data_length: fabric expected data transfer length
1568  * @task_addr: SAM task attribute
1569  * @data_dir: DMA data direction
1570  * @flags: flags for command submission from target_sc_flags_tables
1571  *
1572  * Task tags are supported if the caller has set @se_cmd->tag.
1573  *
1574  * Returns non zero to signal active I/O shutdown failure.  All other
1575  * setup exceptions will be returned as a SCSI CHECK_CONDITION response,
1576  * but still return zero here.
1577  *
1578  * This may only be called from process context, and also currently
1579  * assumes internal allocation of fabric payload buffer by target-core.
1580  *
1581  * It also assumes interal target core SGL memory allocation.
1582  */
1583 int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1584                 unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1585                 u32 data_length, int task_attr, int data_dir, int flags)
1586 {
1587         return target_submit_cmd_map_sgls(se_cmd, se_sess, cdb, sense,
1588                         unpacked_lun, data_length, task_attr, data_dir,
1589                         flags, NULL, 0, NULL, 0, NULL, 0);
1590 }
1591 EXPORT_SYMBOL(target_submit_cmd);
1592
1593 static void target_complete_tmr_failure(struct work_struct *work)
1594 {
1595         struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1596
1597         se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1598         se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1599
1600         transport_cmd_check_stop_to_fabric(se_cmd);
1601 }
1602
1603 /**
1604  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1605  *                     for TMR CDBs
1606  *
1607  * @se_cmd: command descriptor to submit
1608  * @se_sess: associated se_sess for endpoint
1609  * @sense: pointer to SCSI sense buffer
1610  * @unpacked_lun: unpacked LUN to reference for struct se_lun
1611  * @fabric_context: fabric context for TMR req
1612  * @tm_type: Type of TM request
1613  * @gfp: gfp type for caller
1614  * @tag: referenced task tag for TMR_ABORT_TASK
1615  * @flags: submit cmd flags
1616  *
1617  * Callable from all contexts.
1618  **/
1619
1620 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1621                 unsigned char *sense, u64 unpacked_lun,
1622                 void *fabric_tmr_ptr, unsigned char tm_type,
1623                 gfp_t gfp, u64 tag, int flags)
1624 {
1625         struct se_portal_group *se_tpg;
1626         int ret;
1627
1628         se_tpg = se_sess->se_tpg;
1629         BUG_ON(!se_tpg);
1630
1631         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1632                               0, DMA_NONE, TCM_SIMPLE_TAG, sense);
1633         /*
1634          * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
1635          * allocation failure.
1636          */
1637         ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
1638         if (ret < 0)
1639                 return -ENOMEM;
1640
1641         if (tm_type == TMR_ABORT_TASK)
1642                 se_cmd->se_tmr_req->ref_task_tag = tag;
1643
1644         /* See target_submit_cmd for commentary */
1645         ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1646         if (ret) {
1647                 core_tmr_release_req(se_cmd->se_tmr_req);
1648                 return ret;
1649         }
1650
1651         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
1652         if (ret) {
1653                 /*
1654                  * For callback during failure handling, push this work off
1655                  * to process context with TMR_LUN_DOES_NOT_EXIST status.
1656                  */
1657                 INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
1658                 schedule_work(&se_cmd->work);
1659                 return 0;
1660         }
1661         transport_generic_handle_tmr(se_cmd);
1662         return 0;
1663 }
1664 EXPORT_SYMBOL(target_submit_tmr);
1665
1666 /*
1667  * Handle SAM-esque emulation for generic transport request failures.
1668  */
1669 void transport_generic_request_failure(struct se_cmd *cmd,
1670                 sense_reason_t sense_reason)
1671 {
1672         int ret = 0, post_ret = 0;
1673
1674         pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08llx"
1675                 " CDB: 0x%02x\n", cmd, cmd->tag, cmd->t_task_cdb[0]);
1676         pr_debug("-----[ i_state: %d t_state: %d sense_reason: %d\n",
1677                 cmd->se_tfo->get_cmd_state(cmd),
1678                 cmd->t_state, sense_reason);
1679         pr_debug("-----[ CMD_T_ACTIVE: %d CMD_T_STOP: %d CMD_T_SENT: %d\n",
1680                 (cmd->transport_state & CMD_T_ACTIVE) != 0,
1681                 (cmd->transport_state & CMD_T_STOP) != 0,
1682                 (cmd->transport_state & CMD_T_SENT) != 0);
1683
1684         /*
1685          * For SAM Task Attribute emulation for failed struct se_cmd
1686          */
1687         transport_complete_task_attr(cmd);
1688         /*
1689          * Handle special case for COMPARE_AND_WRITE failure, where the
1690          * callback is expected to drop the per device ->caw_sem.
1691          */
1692         if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
1693              cmd->transport_complete_callback)
1694                 cmd->transport_complete_callback(cmd, false, &post_ret);
1695
1696         switch (sense_reason) {
1697         case TCM_NON_EXISTENT_LUN:
1698         case TCM_UNSUPPORTED_SCSI_OPCODE:
1699         case TCM_INVALID_CDB_FIELD:
1700         case TCM_INVALID_PARAMETER_LIST:
1701         case TCM_PARAMETER_LIST_LENGTH_ERROR:
1702         case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
1703         case TCM_UNKNOWN_MODE_PAGE:
1704         case TCM_WRITE_PROTECTED:
1705         case TCM_ADDRESS_OUT_OF_RANGE:
1706         case TCM_CHECK_CONDITION_ABORT_CMD:
1707         case TCM_CHECK_CONDITION_UNIT_ATTENTION:
1708         case TCM_CHECK_CONDITION_NOT_READY:
1709         case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
1710         case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
1711         case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
1712                 break;
1713         case TCM_OUT_OF_RESOURCES:
1714                 sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1715                 break;
1716         case TCM_RESERVATION_CONFLICT:
1717                 /*
1718                  * No SENSE Data payload for this case, set SCSI Status
1719                  * and queue the response to $FABRIC_MOD.
1720                  *
1721                  * Uses linux/include/scsi/scsi.h SAM status codes defs
1722                  */
1723                 cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
1724                 /*
1725                  * For UA Interlock Code 11b, a RESERVATION CONFLICT will
1726                  * establish a UNIT ATTENTION with PREVIOUS RESERVATION
1727                  * CONFLICT STATUS.
1728                  *
1729                  * See spc4r17, section 7.4.6 Control Mode Page, Table 349
1730                  */
1731                 if (cmd->se_sess &&
1732                     cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl == 2) {
1733                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
1734                                                cmd->orig_fe_lun, 0x2C,
1735                                         ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
1736                 }
1737                 trace_target_cmd_complete(cmd);
1738                 ret = cmd->se_tfo->queue_status(cmd);
1739                 if (ret == -EAGAIN || ret == -ENOMEM)
1740                         goto queue_full;
1741                 goto check_stop;
1742         default:
1743                 pr_err("Unknown transport error for CDB 0x%02x: %d\n",
1744                         cmd->t_task_cdb[0], sense_reason);
1745                 sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
1746                 break;
1747         }
1748
1749         ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
1750         if (ret == -EAGAIN || ret == -ENOMEM)
1751                 goto queue_full;
1752
1753 check_stop:
1754         transport_lun_remove_cmd(cmd);
1755         transport_cmd_check_stop_to_fabric(cmd);
1756         return;
1757
1758 queue_full:
1759         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
1760         transport_handle_queue_full(cmd, cmd->se_dev);
1761 }
1762 EXPORT_SYMBOL(transport_generic_request_failure);
1763
1764 void __target_execute_cmd(struct se_cmd *cmd)
1765 {
1766         sense_reason_t ret;
1767
1768         if (cmd->execute_cmd) {
1769                 ret = cmd->execute_cmd(cmd);
1770                 if (ret) {
1771                         spin_lock_irq(&cmd->t_state_lock);
1772                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1773                         spin_unlock_irq(&cmd->t_state_lock);
1774
1775                         transport_generic_request_failure(cmd, ret);
1776                 }
1777         }
1778 }
1779
1780 static int target_write_prot_action(struct se_cmd *cmd)
1781 {
1782         u32 sectors;
1783         /*
1784          * Perform WRITE_INSERT of PI using software emulation when backend
1785          * device has PI enabled, if the transport has not already generated
1786          * PI using hardware WRITE_INSERT offload.
1787          */
1788         switch (cmd->prot_op) {
1789         case TARGET_PROT_DOUT_INSERT:
1790                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
1791                         sbc_dif_generate(cmd);
1792                 break;
1793         case TARGET_PROT_DOUT_STRIP:
1794                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
1795                         break;
1796
1797                 sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
1798                 cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
1799                                              sectors, 0, cmd->t_prot_sg, 0);
1800                 if (unlikely(cmd->pi_err)) {
1801                         spin_lock_irq(&cmd->t_state_lock);
1802                         cmd->transport_state &= ~(CMD_T_BUSY|CMD_T_SENT);
1803                         spin_unlock_irq(&cmd->t_state_lock);
1804                         transport_generic_request_failure(cmd, cmd->pi_err);
1805                         return -1;
1806                 }
1807                 break;
1808         default:
1809                 break;
1810         }
1811
1812         return 0;
1813 }
1814
1815 static bool target_handle_task_attr(struct se_cmd *cmd)
1816 {
1817         struct se_device *dev = cmd->se_dev;
1818
1819         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1820                 return false;
1821
1822         /*
1823          * Check for the existence of HEAD_OF_QUEUE, and if true return 1
1824          * to allow the passed struct se_cmd list of tasks to the front of the list.
1825          */
1826         switch (cmd->sam_task_attr) {
1827         case TCM_HEAD_TAG:
1828                 pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
1829                          cmd->t_task_cdb[0]);
1830                 return false;
1831         case TCM_ORDERED_TAG:
1832                 atomic_inc_mb(&dev->dev_ordered_sync);
1833
1834                 pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
1835                          cmd->t_task_cdb[0]);
1836
1837                 /*
1838                  * Execute an ORDERED command if no other older commands
1839                  * exist that need to be completed first.
1840                  */
1841                 if (!atomic_read(&dev->simple_cmds))
1842                         return false;
1843                 break;
1844         default:
1845                 /*
1846                  * For SIMPLE and UNTAGGED Task Attribute commands
1847                  */
1848                 atomic_inc_mb(&dev->simple_cmds);
1849                 break;
1850         }
1851
1852         if (atomic_read(&dev->dev_ordered_sync) == 0)
1853                 return false;
1854
1855         spin_lock(&dev->delayed_cmd_lock);
1856         list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
1857         spin_unlock(&dev->delayed_cmd_lock);
1858
1859         pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
1860                 cmd->t_task_cdb[0], cmd->sam_task_attr);
1861         return true;
1862 }
1863
1864 static int __transport_check_aborted_status(struct se_cmd *, int);
1865
1866 void target_execute_cmd(struct se_cmd *cmd)
1867 {
1868         /*
1869          * Determine if frontend context caller is requesting the stopping of
1870          * this command for frontend exceptions.
1871          *
1872          * If the received CDB has aleady been aborted stop processing it here.
1873          */
1874         spin_lock_irq(&cmd->t_state_lock);
1875         if (__transport_check_aborted_status(cmd, 1)) {
1876                 spin_unlock_irq(&cmd->t_state_lock);
1877                 return;
1878         }
1879         if (cmd->transport_state & CMD_T_STOP) {
1880                 pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
1881                         __func__, __LINE__, cmd->tag);
1882
1883                 spin_unlock_irq(&cmd->t_state_lock);
1884                 complete_all(&cmd->t_transport_stop_comp);
1885                 return;
1886         }
1887
1888         cmd->t_state = TRANSPORT_PROCESSING;
1889         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
1890         spin_unlock_irq(&cmd->t_state_lock);
1891
1892         if (target_write_prot_action(cmd))
1893                 return;
1894
1895         if (target_handle_task_attr(cmd)) {
1896                 spin_lock_irq(&cmd->t_state_lock);
1897                 cmd->transport_state &= ~(CMD_T_BUSY | CMD_T_SENT);
1898                 spin_unlock_irq(&cmd->t_state_lock);
1899                 return;
1900         }
1901
1902         __target_execute_cmd(cmd);
1903 }
1904 EXPORT_SYMBOL(target_execute_cmd);
1905
1906 /*
1907  * Process all commands up to the last received ORDERED task attribute which
1908  * requires another blocking boundary
1909  */
1910 static void target_restart_delayed_cmds(struct se_device *dev)
1911 {
1912         for (;;) {
1913                 struct se_cmd *cmd;
1914
1915                 spin_lock(&dev->delayed_cmd_lock);
1916                 if (list_empty(&dev->delayed_cmd_list)) {
1917                         spin_unlock(&dev->delayed_cmd_lock);
1918                         break;
1919                 }
1920
1921                 cmd = list_entry(dev->delayed_cmd_list.next,
1922                                  struct se_cmd, se_delayed_node);
1923                 list_del(&cmd->se_delayed_node);
1924                 spin_unlock(&dev->delayed_cmd_lock);
1925
1926                 __target_execute_cmd(cmd);
1927
1928                 if (cmd->sam_task_attr == TCM_ORDERED_TAG)
1929                         break;
1930         }
1931 }
1932
1933 /*
1934  * Called from I/O completion to determine which dormant/delayed
1935  * and ordered cmds need to have their tasks added to the execution queue.
1936  */
1937 static void transport_complete_task_attr(struct se_cmd *cmd)
1938 {
1939         struct se_device *dev = cmd->se_dev;
1940
1941         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1942                 return;
1943
1944         if (cmd->sam_task_attr == TCM_SIMPLE_TAG) {
1945                 atomic_dec_mb(&dev->simple_cmds);
1946                 dev->dev_cur_ordered_id++;
1947                 pr_debug("Incremented dev->dev_cur_ordered_id: %u for SIMPLE\n",
1948                          dev->dev_cur_ordered_id);
1949         } else if (cmd->sam_task_attr == TCM_HEAD_TAG) {
1950                 dev->dev_cur_ordered_id++;
1951                 pr_debug("Incremented dev_cur_ordered_id: %u for HEAD_OF_QUEUE\n",
1952                          dev->dev_cur_ordered_id);
1953         } else if (cmd->sam_task_attr == TCM_ORDERED_TAG) {
1954                 atomic_dec_mb(&dev->dev_ordered_sync);
1955
1956                 dev->dev_cur_ordered_id++;
1957                 pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n",
1958                          dev->dev_cur_ordered_id);
1959         }
1960
1961         target_restart_delayed_cmds(dev);
1962 }
1963
1964 static void transport_complete_qf(struct se_cmd *cmd)
1965 {
1966         int ret = 0;
1967
1968         transport_complete_task_attr(cmd);
1969
1970         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
1971                 trace_target_cmd_complete(cmd);
1972                 ret = cmd->se_tfo->queue_status(cmd);
1973                 goto out;
1974         }
1975
1976         switch (cmd->data_direction) {
1977         case DMA_FROM_DEVICE:
1978                 if (cmd->scsi_status)
1979                         goto queue_status;
1980
1981                 trace_target_cmd_complete(cmd);
1982                 ret = cmd->se_tfo->queue_data_in(cmd);
1983                 break;
1984         case DMA_TO_DEVICE:
1985                 if (cmd->se_cmd_flags & SCF_BIDI) {
1986                         ret = cmd->se_tfo->queue_data_in(cmd);
1987                         break;
1988                 }
1989                 /* Fall through for DMA_TO_DEVICE */
1990         case DMA_NONE:
1991 queue_status:
1992                 trace_target_cmd_complete(cmd);
1993                 ret = cmd->se_tfo->queue_status(cmd);
1994                 break;
1995         default:
1996                 break;
1997         }
1998
1999 out:
2000         if (ret < 0) {
2001                 transport_handle_queue_full(cmd, cmd->se_dev);
2002                 return;
2003         }
2004         transport_lun_remove_cmd(cmd);
2005         transport_cmd_check_stop_to_fabric(cmd);
2006 }
2007
2008 static void transport_handle_queue_full(
2009         struct se_cmd *cmd,
2010         struct se_device *dev)
2011 {
2012         spin_lock_irq(&dev->qf_cmd_lock);
2013         list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2014         atomic_inc_mb(&dev->dev_qf_count);
2015         spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2016
2017         schedule_work(&cmd->se_dev->qf_work_queue);
2018 }
2019
2020 static bool target_read_prot_action(struct se_cmd *cmd)
2021 {
2022         switch (cmd->prot_op) {
2023         case TARGET_PROT_DIN_STRIP:
2024                 if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2025                         u32 sectors = cmd->data_length >>
2026                                   ilog2(cmd->se_dev->dev_attrib.block_size);
2027
2028                         cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2029                                                      sectors, 0, cmd->t_prot_sg,
2030                                                      0);
2031                         if (cmd->pi_err)
2032                                 return true;
2033                 }
2034                 break;
2035         case TARGET_PROT_DIN_INSERT:
2036                 if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2037                         break;
2038
2039                 sbc_dif_generate(cmd);
2040                 break;
2041         default:
2042                 break;
2043         }
2044
2045         return false;
2046 }
2047
2048 static void target_complete_ok_work(struct work_struct *work)
2049 {
2050         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2051         int ret;
2052
2053         /*
2054          * Check if we need to move delayed/dormant tasks from cmds on the
2055          * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2056          * Attribute.
2057          */
2058         transport_complete_task_attr(cmd);
2059
2060         /*
2061          * Check to schedule QUEUE_FULL work, or execute an existing
2062          * cmd->transport_qf_callback()
2063          */
2064         if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2065                 schedule_work(&cmd->se_dev->qf_work_queue);
2066
2067         /*
2068          * Check if we need to send a sense buffer from
2069          * the struct se_cmd in question.
2070          */
2071         if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2072                 WARN_ON(!cmd->scsi_status);
2073                 ret = transport_send_check_condition_and_sense(
2074                                         cmd, 0, 1);
2075                 if (ret == -EAGAIN || ret == -ENOMEM)
2076                         goto queue_full;
2077
2078                 transport_lun_remove_cmd(cmd);
2079                 transport_cmd_check_stop_to_fabric(cmd);
2080                 return;
2081         }
2082         /*
2083          * Check for a callback, used by amongst other things
2084          * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2085          */
2086         if (cmd->transport_complete_callback) {
2087                 sense_reason_t rc;
2088                 bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2089                 bool zero_dl = !(cmd->data_length);
2090                 int post_ret = 0;
2091
2092                 rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2093                 if (!rc && !post_ret) {
2094                         if (caw && zero_dl)
2095                                 goto queue_rsp;
2096
2097                         return;
2098                 } else if (rc) {
2099                         ret = transport_send_check_condition_and_sense(cmd,
2100                                                 rc, 0);
2101                         if (ret == -EAGAIN || ret == -ENOMEM)
2102                                 goto queue_full;
2103
2104                         transport_lun_remove_cmd(cmd);
2105                         transport_cmd_check_stop_to_fabric(cmd);
2106                         return;
2107                 }
2108         }
2109
2110 queue_rsp:
2111         switch (cmd->data_direction) {
2112         case DMA_FROM_DEVICE:
2113                 if (cmd->scsi_status)
2114                         goto queue_status;
2115
2116                 atomic_long_add(cmd->data_length,
2117                                 &cmd->se_lun->lun_stats.tx_data_octets);
2118                 /*
2119                  * Perform READ_STRIP of PI using software emulation when
2120                  * backend had PI enabled, if the transport will not be
2121                  * performing hardware READ_STRIP offload.
2122                  */
2123                 if (target_read_prot_action(cmd)) {
2124                         ret = transport_send_check_condition_and_sense(cmd,
2125                                                 cmd->pi_err, 0);
2126                         if (ret == -EAGAIN || ret == -ENOMEM)
2127                                 goto queue_full;
2128
2129                         transport_lun_remove_cmd(cmd);
2130                         transport_cmd_check_stop_to_fabric(cmd);
2131                         return;
2132                 }
2133
2134                 trace_target_cmd_complete(cmd);
2135                 ret = cmd->se_tfo->queue_data_in(cmd);
2136                 if (ret == -EAGAIN || ret == -ENOMEM)
2137                         goto queue_full;
2138                 break;
2139         case DMA_TO_DEVICE:
2140                 atomic_long_add(cmd->data_length,
2141                                 &cmd->se_lun->lun_stats.rx_data_octets);
2142                 /*
2143                  * Check if we need to send READ payload for BIDI-COMMAND
2144                  */
2145                 if (cmd->se_cmd_flags & SCF_BIDI) {
2146                         atomic_long_add(cmd->data_length,
2147                                         &cmd->se_lun->lun_stats.tx_data_octets);
2148                         ret = cmd->se_tfo->queue_data_in(cmd);
2149                         if (ret == -EAGAIN || ret == -ENOMEM)
2150                                 goto queue_full;
2151                         break;
2152                 }
2153                 /* Fall through for DMA_TO_DEVICE */
2154         case DMA_NONE:
2155 queue_status:
2156                 trace_target_cmd_complete(cmd);
2157                 ret = cmd->se_tfo->queue_status(cmd);
2158                 if (ret == -EAGAIN || ret == -ENOMEM)
2159                         goto queue_full;
2160                 break;
2161         default:
2162                 break;
2163         }
2164
2165         transport_lun_remove_cmd(cmd);
2166         transport_cmd_check_stop_to_fabric(cmd);
2167         return;
2168
2169 queue_full:
2170         pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2171                 " data_direction: %d\n", cmd, cmd->data_direction);
2172         cmd->t_state = TRANSPORT_COMPLETE_QF_OK;
2173         transport_handle_queue_full(cmd, cmd->se_dev);
2174 }
2175
2176 void target_free_sgl(struct scatterlist *sgl, int nents)
2177 {
2178         struct scatterlist *sg;
2179         int count;
2180
2181         for_each_sg(sgl, sg, nents, count)
2182                 __free_page(sg_page(sg));
2183
2184         kfree(sgl);
2185 }
2186 EXPORT_SYMBOL(target_free_sgl);
2187
2188 static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2189 {
2190         /*
2191          * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2192          * emulation, and free + reset pointers if necessary..
2193          */
2194         if (!cmd->t_data_sg_orig)
2195                 return;
2196
2197         kfree(cmd->t_data_sg);
2198         cmd->t_data_sg = cmd->t_data_sg_orig;
2199         cmd->t_data_sg_orig = NULL;
2200         cmd->t_data_nents = cmd->t_data_nents_orig;
2201         cmd->t_data_nents_orig = 0;
2202 }
2203
2204 static inline void transport_free_pages(struct se_cmd *cmd)
2205 {
2206         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2207                 target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2208                 cmd->t_prot_sg = NULL;
2209                 cmd->t_prot_nents = 0;
2210         }
2211
2212         if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2213                 /*
2214                  * Release special case READ buffer payload required for
2215                  * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2216                  */
2217                 if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2218                         target_free_sgl(cmd->t_bidi_data_sg,
2219                                            cmd->t_bidi_data_nents);
2220                         cmd->t_bidi_data_sg = NULL;
2221                         cmd->t_bidi_data_nents = 0;
2222                 }
2223                 transport_reset_sgl_orig(cmd);
2224                 return;
2225         }
2226         transport_reset_sgl_orig(cmd);
2227
2228         target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2229         cmd->t_data_sg = NULL;
2230         cmd->t_data_nents = 0;
2231
2232         target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2233         cmd->t_bidi_data_sg = NULL;
2234         cmd->t_bidi_data_nents = 0;
2235 }
2236
2237 /**
2238  * transport_put_cmd - release a reference to a command
2239  * @cmd:       command to release
2240  *
2241  * This routine releases our reference to the command and frees it if possible.
2242  */
2243 static int transport_put_cmd(struct se_cmd *cmd)
2244 {
2245         BUG_ON(!cmd->se_tfo);
2246         /*
2247          * If this cmd has been setup with target_get_sess_cmd(), drop
2248          * the kref and call ->release_cmd() in kref callback.
2249          */
2250         return target_put_sess_cmd(cmd);
2251 }
2252
2253 void *transport_kmap_data_sg(struct se_cmd *cmd)
2254 {
2255         struct scatterlist *sg = cmd->t_data_sg;
2256         struct page **pages;
2257         int i;
2258
2259         /*
2260          * We need to take into account a possible offset here for fabrics like
2261          * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2262          * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2263          */
2264         if (!cmd->t_data_nents)
2265                 return NULL;
2266
2267         BUG_ON(!sg);
2268         if (cmd->t_data_nents == 1)
2269                 return kmap(sg_page(sg)) + sg->offset;
2270
2271         /* >1 page. use vmap */
2272         pages = kmalloc(sizeof(*pages) * cmd->t_data_nents, GFP_KERNEL);
2273         if (!pages)
2274                 return NULL;
2275
2276         /* convert sg[] to pages[] */
2277         for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2278                 pages[i] = sg_page(sg);
2279         }
2280
2281         cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2282         kfree(pages);
2283         if (!cmd->t_data_vmap)
2284                 return NULL;
2285
2286         return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2287 }
2288 EXPORT_SYMBOL(transport_kmap_data_sg);
2289
2290 void transport_kunmap_data_sg(struct se_cmd *cmd)
2291 {
2292         if (!cmd->t_data_nents) {
2293                 return;
2294         } else if (cmd->t_data_nents == 1) {
2295                 kunmap(sg_page(cmd->t_data_sg));
2296                 return;
2297         }
2298
2299         vunmap(cmd->t_data_vmap);
2300         cmd->t_data_vmap = NULL;
2301 }
2302 EXPORT_SYMBOL(transport_kunmap_data_sg);
2303
2304 int
2305 target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2306                  bool zero_page, bool chainable)
2307 {
2308         struct scatterlist *sg;
2309         struct page *page;
2310         gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
2311         unsigned int nalloc, nent;
2312         int i = 0;
2313
2314         nalloc = nent = DIV_ROUND_UP(length, PAGE_SIZE);
2315         if (chainable)
2316                 nalloc++;
2317         sg = kmalloc_array(nalloc, sizeof(struct scatterlist), GFP_KERNEL);
2318         if (!sg)
2319                 return -ENOMEM;
2320
2321         sg_init_table(sg, nalloc);
2322
2323         while (length) {
2324                 u32 page_len = min_t(u32, length, PAGE_SIZE);
2325                 page = alloc_page(GFP_KERNEL | zero_flag);
2326                 if (!page)
2327                         goto out;
2328
2329                 sg_set_page(&sg[i], page, page_len, 0);
2330                 length -= page_len;
2331                 i++;
2332         }
2333         *sgl = sg;
2334         *nents = nent;
2335         return 0;
2336
2337 out:
2338         while (i > 0) {
2339                 i--;
2340                 __free_page(sg_page(&sg[i]));
2341         }
2342         kfree(sg);
2343         return -ENOMEM;
2344 }
2345 EXPORT_SYMBOL(target_alloc_sgl);
2346
2347 /*
2348  * Allocate any required resources to execute the command.  For writes we
2349  * might not have the payload yet, so notify the fabric via a call to
2350  * ->write_pending instead. Otherwise place it on the execution queue.
2351  */
2352 sense_reason_t
2353 transport_generic_new_cmd(struct se_cmd *cmd)
2354 {
2355         int ret = 0;
2356         bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2357
2358         if (cmd->prot_op != TARGET_PROT_NORMAL &&
2359             !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2360                 ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2361                                        cmd->prot_length, true, false);
2362                 if (ret < 0)
2363                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2364         }
2365
2366         /*
2367          * Determine is the TCM fabric module has already allocated physical
2368          * memory, and is directly calling transport_generic_map_mem_to_cmd()
2369          * beforehand.
2370          */
2371         if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2372             cmd->data_length) {
2373
2374                 if ((cmd->se_cmd_flags & SCF_BIDI) ||
2375                     (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2376                         u32 bidi_length;
2377
2378                         if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2379                                 bidi_length = cmd->t_task_nolb *
2380                                               cmd->se_dev->dev_attrib.block_size;
2381                         else
2382                                 bidi_length = cmd->data_length;
2383
2384                         ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2385                                                &cmd->t_bidi_data_nents,
2386                                                bidi_length, zero_flag, false);
2387                         if (ret < 0)
2388                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2389                 }
2390
2391                 ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2392                                        cmd->data_length, zero_flag, false);
2393                 if (ret < 0)
2394                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2395         } else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2396                     cmd->data_length) {
2397                 /*
2398                  * Special case for COMPARE_AND_WRITE with fabrics
2399                  * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2400                  */
2401                 u32 caw_length = cmd->t_task_nolb *
2402                                  cmd->se_dev->dev_attrib.block_size;
2403
2404                 ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2405                                        &cmd->t_bidi_data_nents,
2406                                        caw_length, zero_flag, false);
2407                 if (ret < 0)
2408                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2409         }
2410         /*
2411          * If this command is not a write we can execute it right here,
2412          * for write buffers we need to notify the fabric driver first
2413          * and let it call back once the write buffers are ready.
2414          */
2415         target_add_to_state_list(cmd);
2416         if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2417                 target_execute_cmd(cmd);
2418                 return 0;
2419         }
2420         transport_cmd_check_stop(cmd, false, true);
2421
2422         ret = cmd->se_tfo->write_pending(cmd);
2423         if (ret == -EAGAIN || ret == -ENOMEM)
2424                 goto queue_full;
2425
2426         /* fabric drivers should only return -EAGAIN or -ENOMEM as error */
2427         WARN_ON(ret);
2428
2429         return (!ret) ? 0 : TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2430
2431 queue_full:
2432         pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2433         cmd->t_state = TRANSPORT_COMPLETE_QF_WP;
2434         transport_handle_queue_full(cmd, cmd->se_dev);
2435         return 0;
2436 }
2437 EXPORT_SYMBOL(transport_generic_new_cmd);
2438
2439 static void transport_write_pending_qf(struct se_cmd *cmd)
2440 {
2441         int ret;
2442
2443         ret = cmd->se_tfo->write_pending(cmd);
2444         if (ret == -EAGAIN || ret == -ENOMEM) {
2445                 pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2446                          cmd);
2447                 transport_handle_queue_full(cmd, cmd->se_dev);
2448         }
2449 }
2450
2451 static bool
2452 __transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2453                            unsigned long *flags);
2454
2455 static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2456 {
2457         unsigned long flags;
2458
2459         spin_lock_irqsave(&cmd->t_state_lock, flags);
2460         __transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2461         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2462 }
2463
2464 int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2465 {
2466         int ret = 0;
2467         bool aborted = false, tas = false;
2468
2469         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
2470                 if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2471                         target_wait_free_cmd(cmd, &aborted, &tas);
2472
2473                 if (!aborted || tas)
2474                         ret = transport_put_cmd(cmd);
2475         } else {
2476                 if (wait_for_tasks)
2477                         target_wait_free_cmd(cmd, &aborted, &tas);
2478                 /*
2479                  * Handle WRITE failure case where transport_generic_new_cmd()
2480                  * has already added se_cmd to state_list, but fabric has
2481                  * failed command before I/O submission.
2482                  */
2483                 if (cmd->state_active)
2484                         target_remove_from_state_list(cmd);
2485
2486                 if (cmd->se_lun)
2487                         transport_lun_remove_cmd(cmd);
2488
2489                 if (!aborted || tas)
2490                         ret = transport_put_cmd(cmd);
2491         }
2492         /*
2493          * If the task has been internally aborted due to TMR ABORT_TASK
2494          * or LUN_RESET, target_core_tmr.c is responsible for performing
2495          * the remaining calls to target_put_sess_cmd(), and not the
2496          * callers of this function.
2497          */
2498         if (aborted) {
2499                 pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2500                 wait_for_completion(&cmd->cmd_wait_comp);
2501                 cmd->se_tfo->release_cmd(cmd);
2502                 ret = 1;
2503         }
2504         return ret;
2505 }
2506 EXPORT_SYMBOL(transport_generic_free_cmd);
2507
2508 /* target_get_sess_cmd - Add command to active ->sess_cmd_list
2509  * @se_cmd:     command descriptor to add
2510  * @ack_kref:   Signal that fabric will perform an ack target_put_sess_cmd()
2511  */
2512 int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
2513 {
2514         struct se_session *se_sess = se_cmd->se_sess;
2515         unsigned long flags;
2516         int ret = 0;
2517
2518         /*
2519          * Add a second kref if the fabric caller is expecting to handle
2520          * fabric acknowledgement that requires two target_put_sess_cmd()
2521          * invocations before se_cmd descriptor release.
2522          */
2523         if (ack_kref)
2524                 kref_get(&se_cmd->cmd_kref);
2525
2526         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2527         if (se_sess->sess_tearing_down) {
2528                 ret = -ESHUTDOWN;
2529                 goto out;
2530         }
2531         list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list);
2532 out:
2533         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2534
2535         if (ret && ack_kref)
2536                 target_put_sess_cmd(se_cmd);
2537
2538         return ret;
2539 }
2540 EXPORT_SYMBOL(target_get_sess_cmd);
2541
2542 static void target_free_cmd_mem(struct se_cmd *cmd)
2543 {
2544         transport_free_pages(cmd);
2545
2546         if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
2547                 core_tmr_release_req(cmd->se_tmr_req);
2548         if (cmd->t_task_cdb != cmd->__t_task_cdb)
2549                 kfree(cmd->t_task_cdb);
2550 }
2551
2552 static void target_release_cmd_kref(struct kref *kref)
2553 {
2554         struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
2555         struct se_session *se_sess = se_cmd->se_sess;
2556         unsigned long flags;
2557         bool fabric_stop;
2558
2559         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2560         if (list_empty(&se_cmd->se_cmd_list)) {
2561                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2562                 target_free_cmd_mem(se_cmd);
2563                 se_cmd->se_tfo->release_cmd(se_cmd);
2564                 return;
2565         }
2566
2567         spin_lock(&se_cmd->t_state_lock);
2568         fabric_stop = (se_cmd->transport_state & CMD_T_FABRIC_STOP);
2569         spin_unlock(&se_cmd->t_state_lock);
2570
2571         if (se_cmd->cmd_wait_set || fabric_stop) {
2572                 list_del_init(&se_cmd->se_cmd_list);
2573                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2574                 target_free_cmd_mem(se_cmd);
2575                 complete(&se_cmd->cmd_wait_comp);
2576                 return;
2577         }
2578         list_del_init(&se_cmd->se_cmd_list);
2579         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2580
2581         target_free_cmd_mem(se_cmd);
2582         se_cmd->se_tfo->release_cmd(se_cmd);
2583 }
2584
2585 /* target_put_sess_cmd - Check for active I/O shutdown via kref_put
2586  * @se_cmd:     command descriptor to drop
2587  */
2588 int target_put_sess_cmd(struct se_cmd *se_cmd)
2589 {
2590         struct se_session *se_sess = se_cmd->se_sess;
2591
2592         if (!se_sess) {
2593                 target_free_cmd_mem(se_cmd);
2594                 se_cmd->se_tfo->release_cmd(se_cmd);
2595                 return 1;
2596         }
2597         return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
2598 }
2599 EXPORT_SYMBOL(target_put_sess_cmd);
2600
2601 /* target_sess_cmd_list_set_waiting - Flag all commands in
2602  *         sess_cmd_list to complete cmd_wait_comp.  Set
2603  *         sess_tearing_down so no more commands are queued.
2604  * @se_sess:    session to flag
2605  */
2606 void target_sess_cmd_list_set_waiting(struct se_session *se_sess)
2607 {
2608         struct se_cmd *se_cmd;
2609         unsigned long flags;
2610         int rc;
2611
2612         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2613         if (se_sess->sess_tearing_down) {
2614                 spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2615                 return;
2616         }
2617         se_sess->sess_tearing_down = 1;
2618         list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list);
2619
2620         list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list) {
2621                 rc = kref_get_unless_zero(&se_cmd->cmd_kref);
2622                 if (rc) {
2623                         se_cmd->cmd_wait_set = 1;
2624                         spin_lock(&se_cmd->t_state_lock);
2625                         se_cmd->transport_state |= CMD_T_FABRIC_STOP;
2626                         spin_unlock(&se_cmd->t_state_lock);
2627                 }
2628         }
2629
2630         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2631 }
2632 EXPORT_SYMBOL(target_sess_cmd_list_set_waiting);
2633
2634 /* target_wait_for_sess_cmds - Wait for outstanding descriptors
2635  * @se_sess:    session to wait for active I/O
2636  */
2637 void target_wait_for_sess_cmds(struct se_session *se_sess)
2638 {
2639         struct se_cmd *se_cmd, *tmp_cmd;
2640         unsigned long flags;
2641         bool tas;
2642
2643         list_for_each_entry_safe(se_cmd, tmp_cmd,
2644                                 &se_sess->sess_wait_list, se_cmd_list) {
2645                 pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:"
2646                         " %d\n", se_cmd, se_cmd->t_state,
2647                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2648
2649                 spin_lock_irqsave(&se_cmd->t_state_lock, flags);
2650                 tas = (se_cmd->transport_state & CMD_T_TAS);
2651                 spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
2652
2653                 if (!target_put_sess_cmd(se_cmd)) {
2654                         if (tas)
2655                                 target_put_sess_cmd(se_cmd);
2656                 }
2657
2658                 wait_for_completion(&se_cmd->cmd_wait_comp);
2659                 pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d"
2660                         " fabric state: %d\n", se_cmd, se_cmd->t_state,
2661                         se_cmd->se_tfo->get_cmd_state(se_cmd));
2662
2663                 se_cmd->se_tfo->release_cmd(se_cmd);
2664         }
2665
2666         spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
2667         WARN_ON(!list_empty(&se_sess->sess_cmd_list));
2668         spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
2669
2670 }
2671 EXPORT_SYMBOL(target_wait_for_sess_cmds);
2672
2673 void transport_clear_lun_ref(struct se_lun *lun)
2674 {
2675         percpu_ref_kill(&lun->lun_ref);
2676         wait_for_completion(&lun->lun_ref_comp);
2677 }
2678
2679 static bool
2680 __transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
2681                            bool *aborted, bool *tas, unsigned long *flags)
2682         __releases(&cmd->t_state_lock)
2683         __acquires(&cmd->t_state_lock)
2684 {
2685
2686         assert_spin_locked(&cmd->t_state_lock);
2687         WARN_ON_ONCE(!irqs_disabled());
2688
2689         if (fabric_stop)
2690                 cmd->transport_state |= CMD_T_FABRIC_STOP;
2691
2692         if (cmd->transport_state & CMD_T_ABORTED)
2693                 *aborted = true;
2694
2695         if (cmd->transport_state & CMD_T_TAS)
2696                 *tas = true;
2697
2698         if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
2699             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2700                 return false;
2701
2702         if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
2703             !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
2704                 return false;
2705
2706         if (!(cmd->transport_state & CMD_T_ACTIVE))
2707                 return false;
2708
2709         if (fabric_stop && *aborted)
2710                 return false;
2711
2712         cmd->transport_state |= CMD_T_STOP;
2713
2714         pr_debug("wait_for_tasks: Stopping %p ITT: 0x%08llx i_state: %d,"
2715                  " t_state: %d, CMD_T_STOP\n", cmd, cmd->tag,
2716                  cmd->se_tfo->get_cmd_state(cmd), cmd->t_state);
2717
2718         spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
2719
2720         wait_for_completion(&cmd->t_transport_stop_comp);
2721
2722         spin_lock_irqsave(&cmd->t_state_lock, *flags);
2723         cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
2724
2725         pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
2726                  "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
2727
2728         return true;
2729 }
2730
2731 /**
2732  * transport_wait_for_tasks - wait for completion to occur
2733  * @cmd:        command to wait
2734  *
2735  * Called from frontend fabric context to wait for storage engine
2736  * to pause and/or release frontend generated struct se_cmd.
2737  */
2738 bool transport_wait_for_tasks(struct se_cmd *cmd)
2739 {
2740         unsigned long flags;
2741         bool ret, aborted = false, tas = false;
2742
2743         spin_lock_irqsave(&cmd->t_state_lock, flags);
2744         ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
2745         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2746
2747         return ret;
2748 }
2749 EXPORT_SYMBOL(transport_wait_for_tasks);
2750
2751 struct sense_info {
2752         u8 key;
2753         u8 asc;
2754         u8 ascq;
2755         bool add_sector_info;
2756 };
2757
2758 static const struct sense_info sense_info_table[] = {
2759         [TCM_NO_SENSE] = {
2760                 .key = NOT_READY
2761         },
2762         [TCM_NON_EXISTENT_LUN] = {
2763                 .key = ILLEGAL_REQUEST,
2764                 .asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
2765         },
2766         [TCM_UNSUPPORTED_SCSI_OPCODE] = {
2767                 .key = ILLEGAL_REQUEST,
2768                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2769         },
2770         [TCM_SECTOR_COUNT_TOO_MANY] = {
2771                 .key = ILLEGAL_REQUEST,
2772                 .asc = 0x20, /* INVALID COMMAND OPERATION CODE */
2773         },
2774         [TCM_UNKNOWN_MODE_PAGE] = {
2775                 .key = ILLEGAL_REQUEST,
2776                 .asc = 0x24, /* INVALID FIELD IN CDB */
2777         },
2778         [TCM_CHECK_CONDITION_ABORT_CMD] = {
2779                 .key = ABORTED_COMMAND,
2780                 .asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
2781                 .ascq = 0x03,
2782         },
2783         [TCM_INCORRECT_AMOUNT_OF_DATA] = {
2784                 .key = ABORTED_COMMAND,
2785                 .asc = 0x0c, /* WRITE ERROR */
2786                 .ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
2787         },
2788         [TCM_INVALID_CDB_FIELD] = {
2789                 .key = ILLEGAL_REQUEST,
2790                 .asc = 0x24, /* INVALID FIELD IN CDB */
2791         },
2792         [TCM_INVALID_PARAMETER_LIST] = {
2793                 .key = ILLEGAL_REQUEST,
2794                 .asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
2795         },
2796         [TCM_PARAMETER_LIST_LENGTH_ERROR] = {
2797                 .key = ILLEGAL_REQUEST,
2798                 .asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
2799         },
2800         [TCM_UNEXPECTED_UNSOLICITED_DATA] = {
2801                 .key = ILLEGAL_REQUEST,
2802                 .asc = 0x0c, /* WRITE ERROR */
2803                 .ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
2804         },
2805         [TCM_SERVICE_CRC_ERROR] = {
2806                 .key = ABORTED_COMMAND,
2807                 .asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
2808                 .ascq = 0x05, /* N/A */
2809         },
2810         [TCM_SNACK_REJECTED] = {
2811                 .key = ABORTED_COMMAND,
2812                 .asc = 0x11, /* READ ERROR */
2813                 .ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
2814         },
2815         [TCM_WRITE_PROTECTED] = {
2816                 .key = DATA_PROTECT,
2817                 .asc = 0x27, /* WRITE PROTECTED */
2818         },
2819         [TCM_ADDRESS_OUT_OF_RANGE] = {
2820                 .key = ILLEGAL_REQUEST,
2821                 .asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
2822         },
2823         [TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
2824                 .key = UNIT_ATTENTION,
2825         },
2826         [TCM_CHECK_CONDITION_NOT_READY] = {
2827                 .key = NOT_READY,
2828         },
2829         [TCM_MISCOMPARE_VERIFY] = {
2830                 .key = MISCOMPARE,
2831                 .asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
2832                 .ascq = 0x00,
2833         },
2834         [TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
2835                 .key = ABORTED_COMMAND,
2836                 .asc = 0x10,
2837                 .ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
2838                 .add_sector_info = true,
2839         },
2840         [TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
2841                 .key = ABORTED_COMMAND,
2842                 .asc = 0x10,
2843                 .ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
2844                 .add_sector_info = true,
2845         },
2846         [TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
2847                 .key = ABORTED_COMMAND,
2848                 .asc = 0x10,
2849                 .ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
2850                 .add_sector_info = true,
2851         },
2852         [TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
2853                 /*
2854                  * Returning ILLEGAL REQUEST would cause immediate IO errors on
2855                  * Solaris initiators.  Returning NOT READY instead means the
2856                  * operations will be retried a finite number of times and we
2857                  * can survive intermittent errors.
2858                  */
2859                 .key = NOT_READY,
2860                 .asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
2861         },
2862 };
2863
2864 static int translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
2865 {
2866         const struct sense_info *si;
2867         u8 *buffer = cmd->sense_buffer;
2868         int r = (__force int)reason;
2869         u8 asc, ascq;
2870         bool desc_format = target_sense_desc_format(cmd->se_dev);
2871
2872         if (r < ARRAY_SIZE(sense_info_table) && sense_info_table[r].key)
2873                 si = &sense_info_table[r];
2874         else
2875                 si = &sense_info_table[(__force int)
2876                                        TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
2877
2878         if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
2879                 core_scsi3_ua_for_check_condition(cmd, &asc, &ascq);
2880                 WARN_ON_ONCE(asc == 0);
2881         } else if (si->asc == 0) {
2882                 WARN_ON_ONCE(cmd->scsi_asc == 0);
2883                 asc = cmd->scsi_asc;
2884                 ascq = cmd->scsi_ascq;
2885         } else {
2886                 asc = si->asc;
2887                 ascq = si->ascq;
2888         }
2889
2890         scsi_build_sense_buffer(desc_format, buffer, si->key, asc, ascq);
2891         if (si->add_sector_info)
2892                 return scsi_set_sense_information(buffer,
2893                                                   cmd->scsi_sense_length,
2894                                                   cmd->bad_sector);
2895
2896         return 0;
2897 }
2898
2899 int
2900 transport_send_check_condition_and_sense(struct se_cmd *cmd,
2901                 sense_reason_t reason, int from_transport)
2902 {
2903         unsigned long flags;
2904
2905         spin_lock_irqsave(&cmd->t_state_lock, flags);
2906         if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
2907                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2908                 return 0;
2909         }
2910         cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
2911         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2912
2913         if (!from_transport) {
2914                 int rc;
2915
2916                 cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
2917                 cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
2918                 cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
2919                 rc = translate_sense_reason(cmd, reason);
2920                 if (rc)
2921                         return rc;
2922         }
2923
2924         trace_target_cmd_complete(cmd);
2925         return cmd->se_tfo->queue_status(cmd);
2926 }
2927 EXPORT_SYMBOL(transport_send_check_condition_and_sense);
2928
2929 static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2930         __releases(&cmd->t_state_lock)
2931         __acquires(&cmd->t_state_lock)
2932 {
2933         assert_spin_locked(&cmd->t_state_lock);
2934         WARN_ON_ONCE(!irqs_disabled());
2935
2936         if (!(cmd->transport_state & CMD_T_ABORTED))
2937                 return 0;
2938         /*
2939          * If cmd has been aborted but either no status is to be sent or it has
2940          * already been sent, just return
2941          */
2942         if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) {
2943                 if (send_status)
2944                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2945                 return 1;
2946         }
2947
2948         pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:"
2949                 " 0x%02x ITT: 0x%08llx\n", cmd->t_task_cdb[0], cmd->tag);
2950
2951         cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
2952         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
2953         trace_target_cmd_complete(cmd);
2954
2955         spin_unlock_irq(&cmd->t_state_lock);
2956         cmd->se_tfo->queue_status(cmd);
2957         spin_lock_irq(&cmd->t_state_lock);
2958
2959         return 1;
2960 }
2961
2962 int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
2963 {
2964         int ret;
2965
2966         spin_lock_irq(&cmd->t_state_lock);
2967         ret = __transport_check_aborted_status(cmd, send_status);
2968         spin_unlock_irq(&cmd->t_state_lock);
2969
2970         return ret;
2971 }
2972 EXPORT_SYMBOL(transport_check_aborted_status);
2973
2974 void transport_send_task_abort(struct se_cmd *cmd)
2975 {
2976         unsigned long flags;
2977
2978         spin_lock_irqsave(&cmd->t_state_lock, flags);
2979         if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
2980                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2981                 return;
2982         }
2983         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2984
2985         /*
2986          * If there are still expected incoming fabric WRITEs, we wait
2987          * until until they have completed before sending a TASK_ABORTED
2988          * response.  This response with TASK_ABORTED status will be
2989          * queued back to fabric module by transport_check_aborted_status().
2990          */
2991         if (cmd->data_direction == DMA_TO_DEVICE) {
2992                 if (cmd->se_tfo->write_pending_status(cmd) != 0) {
2993                         spin_lock_irqsave(&cmd->t_state_lock, flags);
2994                         if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) {
2995                                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2996                                 goto send_abort;
2997                         }
2998                         cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
2999                         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3000                         return;
3001                 }
3002         }
3003 send_abort:
3004         cmd->scsi_status = SAM_STAT_TASK_ABORTED;
3005
3006         transport_lun_remove_cmd(cmd);
3007
3008         pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
3009                  cmd->t_task_cdb[0], cmd->tag);
3010
3011         trace_target_cmd_complete(cmd);
3012         cmd->se_tfo->queue_status(cmd);
3013 }
3014
3015 static void target_tmr_work(struct work_struct *work)
3016 {
3017         struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3018         struct se_device *dev = cmd->se_dev;
3019         struct se_tmr_req *tmr = cmd->se_tmr_req;
3020         unsigned long flags;
3021         int ret;
3022
3023         spin_lock_irqsave(&cmd->t_state_lock, flags);
3024         if (cmd->transport_state & CMD_T_ABORTED) {
3025                 tmr->response = TMR_FUNCTION_REJECTED;
3026                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3027                 goto check_stop;
3028         }
3029         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3030
3031         switch (tmr->function) {
3032         case TMR_ABORT_TASK:
3033                 core_tmr_abort_task(dev, tmr, cmd->se_sess);
3034                 break;
3035         case TMR_ABORT_TASK_SET:
3036         case TMR_CLEAR_ACA:
3037         case TMR_CLEAR_TASK_SET:
3038                 tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3039                 break;
3040         case TMR_LUN_RESET:
3041                 ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3042                 tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3043                                          TMR_FUNCTION_REJECTED;
3044                 if (tmr->response == TMR_FUNCTION_COMPLETE) {
3045                         target_ua_allocate_lun(cmd->se_sess->se_node_acl,
3046                                                cmd->orig_fe_lun, 0x29,
3047                                                ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3048                 }
3049                 break;
3050         case TMR_TARGET_WARM_RESET:
3051                 tmr->response = TMR_FUNCTION_REJECTED;
3052                 break;
3053         case TMR_TARGET_COLD_RESET:
3054                 tmr->response = TMR_FUNCTION_REJECTED;
3055                 break;
3056         default:
3057                 pr_err("Uknown TMR function: 0x%02x.\n",
3058                                 tmr->function);
3059                 tmr->response = TMR_FUNCTION_REJECTED;
3060                 break;
3061         }
3062
3063         spin_lock_irqsave(&cmd->t_state_lock, flags);
3064         if (cmd->transport_state & CMD_T_ABORTED) {
3065                 spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3066                 goto check_stop;
3067         }
3068         cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3069         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3070
3071         cmd->se_tfo->queue_tm_rsp(cmd);
3072
3073 check_stop:
3074         transport_cmd_check_stop_to_fabric(cmd);
3075 }
3076
3077 int transport_generic_handle_tmr(
3078         struct se_cmd *cmd)
3079 {
3080         unsigned long flags;
3081
3082         spin_lock_irqsave(&cmd->t_state_lock, flags);
3083         cmd->transport_state |= CMD_T_ACTIVE;
3084         spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3085
3086         INIT_WORK(&cmd->work, target_tmr_work);
3087         queue_work(cmd->se_dev->tmr_wq, &cmd->work);
3088         return 0;
3089 }
3090 EXPORT_SYMBOL(transport_generic_handle_tmr);
3091
3092 bool
3093 target_check_wce(struct se_device *dev)
3094 {
3095         bool wce = false;
3096
3097         if (dev->transport->get_write_cache)
3098                 wce = dev->transport->get_write_cache(dev);
3099         else if (dev->dev_attrib.emulate_write_cache > 0)
3100                 wce = true;
3101
3102         return wce;
3103 }
3104
3105 bool
3106 target_check_fua(struct se_device *dev)
3107 {
3108         return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3109 }