target_core_transport.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*******************************************************************************
   3 * Filename:  target_core_transport.c
   4 *
   5 * This file contains the Generic Target Engine Core.
   6 *
   7 * (c) Copyright 2002-2013 Datera, Inc.
   8 *
   9 * Nicholas A. Bellinger <nab@kernel.org>
  10 *
  11 ******************************************************************************/
  12
  13#include <linux/net.h>
  14#include <linux/delay.h>
  15#include <linux/string.h>
  16#include <linux/timer.h>
  17#include <linux/slab.h>
  18#include <linux/spinlock.h>
  19#include <linux/kthread.h>
  20#include <linux/in.h>
  21#include <linux/cdrom.h>
  22#include <linux/module.h>
  23#include <linux/ratelimit.h>
  24#include <linux/vmalloc.h>
  25#include <linux/unaligned.h>
  26#include <net/sock.h>
  27#include <net/tcp.h>
  28#include <scsi/scsi_proto.h>
  29#include <scsi/scsi_common.h>
  30
  31#include <target/target_core_base.h>
  32#include <target/target_core_backend.h>
  33#include <target/target_core_fabric.h>
  34
  35#include "target_core_internal.h"
  36#include "target_core_alua.h"
  37#include "target_core_pr.h"
  38#include "target_core_ua.h"
  39
  40#define CREATE_TRACE_POINTS
  41#include <trace/events/target.h>
  42
  43static struct workqueue_struct *target_completion_wq;
  44static struct workqueue_struct *target_submission_wq;
  45static struct kmem_cache *se_sess_cache;
  46struct kmem_cache *se_ua_cache;
  47struct kmem_cache *t10_pr_reg_cache;
  48struct kmem_cache *t10_alua_lu_gp_cache;
  49struct kmem_cache *t10_alua_lu_gp_mem_cache;
  50struct kmem_cache *t10_alua_tg_pt_gp_cache;
  51struct kmem_cache *t10_alua_lba_map_cache;
  52struct kmem_cache *t10_alua_lba_map_mem_cache;
  53
  54static void transport_complete_task_attr(struct se_cmd *cmd);
  55static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason);
  56static void transport_handle_queue_full(struct se_cmd *cmd,
  57		struct se_device *dev, int err, bool write_pending);
  58static void target_complete_ok_work(struct work_struct *work);
  59
  60int init_se_kmem_caches(void)
  61{
  62	se_sess_cache = kmem_cache_create("se_sess_cache",
  63			sizeof(struct se_session), __alignof__(struct se_session),
  64			0, NULL);
  65	if (!se_sess_cache) {
  66		pr_err("kmem_cache_create() for struct se_session"
  67				" failed\n");
  68		goto out;
  69	}
  70	se_ua_cache = kmem_cache_create("se_ua_cache",
  71			sizeof(struct se_ua), __alignof__(struct se_ua),
  72			0, NULL);
  73	if (!se_ua_cache) {
  74		pr_err("kmem_cache_create() for struct se_ua failed\n");
  75		goto out_free_sess_cache;
  76	}
  77	t10_pr_reg_cache = kmem_cache_create("t10_pr_reg_cache",
  78			sizeof(struct t10_pr_registration),
  79			__alignof__(struct t10_pr_registration), 0, NULL);
  80	if (!t10_pr_reg_cache) {
  81		pr_err("kmem_cache_create() for struct t10_pr_registration"
  82				" failed\n");
  83		goto out_free_ua_cache;
  84	}
  85	t10_alua_lu_gp_cache = kmem_cache_create("t10_alua_lu_gp_cache",
  86			sizeof(struct t10_alua_lu_gp), __alignof__(struct t10_alua_lu_gp),
  87			0, NULL);
  88	if (!t10_alua_lu_gp_cache) {
  89		pr_err("kmem_cache_create() for t10_alua_lu_gp_cache"
  90				" failed\n");
  91		goto out_free_pr_reg_cache;
  92	}
  93	t10_alua_lu_gp_mem_cache = kmem_cache_create("t10_alua_lu_gp_mem_cache",
  94			sizeof(struct t10_alua_lu_gp_member),
  95			__alignof__(struct t10_alua_lu_gp_member), 0, NULL);
  96	if (!t10_alua_lu_gp_mem_cache) {
  97		pr_err("kmem_cache_create() for t10_alua_lu_gp_mem_"
  98				"cache failed\n");
  99		goto out_free_lu_gp_cache;
 100	}
 101	t10_alua_tg_pt_gp_cache = kmem_cache_create("t10_alua_tg_pt_gp_cache",
 102			sizeof(struct t10_alua_tg_pt_gp),
 103			__alignof__(struct t10_alua_tg_pt_gp), 0, NULL);
 104	if (!t10_alua_tg_pt_gp_cache) {
 105		pr_err("kmem_cache_create() for t10_alua_tg_pt_gp_"
 106				"cache failed\n");
 107		goto out_free_lu_gp_mem_cache;
 108	}
 109	t10_alua_lba_map_cache = kmem_cache_create(
 110			"t10_alua_lba_map_cache",
 111			sizeof(struct t10_alua_lba_map),
 112			__alignof__(struct t10_alua_lba_map), 0, NULL);
 113	if (!t10_alua_lba_map_cache) {
 114		pr_err("kmem_cache_create() for t10_alua_lba_map_"
 115				"cache failed\n");
 116		goto out_free_tg_pt_gp_cache;
 117	}
 118	t10_alua_lba_map_mem_cache = kmem_cache_create(
 119			"t10_alua_lba_map_mem_cache",
 120			sizeof(struct t10_alua_lba_map_member),
 121			__alignof__(struct t10_alua_lba_map_member), 0, NULL);
 122	if (!t10_alua_lba_map_mem_cache) {
 123		pr_err("kmem_cache_create() for t10_alua_lba_map_mem_"
 124				"cache failed\n");
 125		goto out_free_lba_map_cache;
 126	}
 127
 128	target_completion_wq = alloc_workqueue("target_completion",
 129					       WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 130	if (!target_completion_wq)
 131		goto out_free_lba_map_mem_cache;
 132
 133	target_submission_wq = alloc_workqueue("target_submission",
 134					       WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 135	if (!target_submission_wq)
 136		goto out_free_completion_wq;
 137
 138	return 0;
 139
 140out_free_completion_wq:
 141	destroy_workqueue(target_completion_wq);
 142out_free_lba_map_mem_cache:
 143	kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 144out_free_lba_map_cache:
 145	kmem_cache_destroy(t10_alua_lba_map_cache);
 146out_free_tg_pt_gp_cache:
 147	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 148out_free_lu_gp_mem_cache:
 149	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 150out_free_lu_gp_cache:
 151	kmem_cache_destroy(t10_alua_lu_gp_cache);
 152out_free_pr_reg_cache:
 153	kmem_cache_destroy(t10_pr_reg_cache);
 154out_free_ua_cache:
 155	kmem_cache_destroy(se_ua_cache);
 156out_free_sess_cache:
 157	kmem_cache_destroy(se_sess_cache);
 158out:
 159	return -ENOMEM;
 160}
 161
 162void release_se_kmem_caches(void)
 163{
 164	destroy_workqueue(target_submission_wq);
 165	destroy_workqueue(target_completion_wq);
 166	kmem_cache_destroy(se_sess_cache);
 167	kmem_cache_destroy(se_ua_cache);
 168	kmem_cache_destroy(t10_pr_reg_cache);
 169	kmem_cache_destroy(t10_alua_lu_gp_cache);
 170	kmem_cache_destroy(t10_alua_lu_gp_mem_cache);
 171	kmem_cache_destroy(t10_alua_tg_pt_gp_cache);
 172	kmem_cache_destroy(t10_alua_lba_map_cache);
 173	kmem_cache_destroy(t10_alua_lba_map_mem_cache);
 174}
 175
 176/* This code ensures unique mib indexes are handed out. */
 177static DEFINE_SPINLOCK(scsi_mib_index_lock);
 178static u32 scsi_mib_index[SCSI_INDEX_TYPE_MAX];
 179
 180/*
 181 * Allocate a new row index for the entry type specified
 182 */
 183u32 scsi_get_new_index(scsi_index_t type)
 184{
 185	u32 new_index;
 186
 187	BUG_ON((type < 0) || (type >= SCSI_INDEX_TYPE_MAX));
 188
 189	spin_lock(&scsi_mib_index_lock);
 190	new_index = ++scsi_mib_index[type];
 191	spin_unlock(&scsi_mib_index_lock);
 192
 193	return new_index;
 194}
 195
 196void transport_subsystem_check_init(void)
 197{
 198	int ret;
 199	static int sub_api_initialized;
 200
 201	if (sub_api_initialized)
 202		return;
 203
 204	ret = IS_ENABLED(CONFIG_TCM_IBLOCK) && request_module("target_core_iblock");
 205	if (ret != 0)
 206		pr_err("Unable to load target_core_iblock\n");
 207
 208	ret = IS_ENABLED(CONFIG_TCM_FILEIO) && request_module("target_core_file");
 209	if (ret != 0)
 210		pr_err("Unable to load target_core_file\n");
 211
 212	ret = IS_ENABLED(CONFIG_TCM_PSCSI) && request_module("target_core_pscsi");
 213	if (ret != 0)
 214		pr_err("Unable to load target_core_pscsi\n");
 215
 216	ret = IS_ENABLED(CONFIG_TCM_USER2) && request_module("target_core_user");
 217	if (ret != 0)
 218		pr_err("Unable to load target_core_user\n");
 219
 220	sub_api_initialized = 1;
 221}
 222
 223static void target_release_cmd_refcnt(struct percpu_ref *ref)
 224{
 225	struct target_cmd_counter *cmd_cnt  = container_of(ref,
 226							   typeof(*cmd_cnt),
 227							   refcnt);
 228	wake_up(&cmd_cnt->refcnt_wq);
 229}
 230
 231struct target_cmd_counter *target_alloc_cmd_counter(void)
 232{
 233	struct target_cmd_counter *cmd_cnt;
 234	int rc;
 235
 236	cmd_cnt = kzalloc(sizeof(*cmd_cnt), GFP_KERNEL);
 237	if (!cmd_cnt)
 238		return NULL;
 239
 240	init_completion(&cmd_cnt->stop_done);
 241	init_waitqueue_head(&cmd_cnt->refcnt_wq);
 242	atomic_set(&cmd_cnt->stopped, 0);
 243
 244	rc = percpu_ref_init(&cmd_cnt->refcnt, target_release_cmd_refcnt, 0,
 245			     GFP_KERNEL);
 246	if (rc)
 247		goto free_cmd_cnt;
 248
 249	return cmd_cnt;
 250
 251free_cmd_cnt:
 252	kfree(cmd_cnt);
 253	return NULL;
 254}
 255EXPORT_SYMBOL_GPL(target_alloc_cmd_counter);
 256
 257void target_free_cmd_counter(struct target_cmd_counter *cmd_cnt)
 258{
 259	/*
 260	 * Drivers like loop do not call target_stop_session during session
 261	 * shutdown so we have to drop the ref taken at init time here.
 262	 */
 263	if (!atomic_read(&cmd_cnt->stopped))
 264		percpu_ref_put(&cmd_cnt->refcnt);
 265
 266	percpu_ref_exit(&cmd_cnt->refcnt);
 267	kfree(cmd_cnt);
 268}
 269EXPORT_SYMBOL_GPL(target_free_cmd_counter);
 270
 271/**
 272 * transport_init_session - initialize a session object
 273 * @se_sess: Session object pointer.
 274 *
 275 * The caller must have zero-initialized @se_sess before calling this function.
 276 */
 277void transport_init_session(struct se_session *se_sess)
 278{
 279	INIT_LIST_HEAD(&se_sess->sess_list);
 280	INIT_LIST_HEAD(&se_sess->sess_acl_list);
 281	spin_lock_init(&se_sess->sess_cmd_lock);
 282}
 283EXPORT_SYMBOL(transport_init_session);
 284
 285/**
 286 * transport_alloc_session - allocate a session object and initialize it
 287 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
 288 */
 289struct se_session *transport_alloc_session(enum target_prot_op sup_prot_ops)
 290{
 291	struct se_session *se_sess;
 292
 293	se_sess = kmem_cache_zalloc(se_sess_cache, GFP_KERNEL);
 294	if (!se_sess) {
 295		pr_err("Unable to allocate struct se_session from"
 296				" se_sess_cache\n");
 297		return ERR_PTR(-ENOMEM);
 298	}
 299	transport_init_session(se_sess);
 300	se_sess->sup_prot_ops = sup_prot_ops;
 301
 302	return se_sess;
 303}
 304EXPORT_SYMBOL(transport_alloc_session);
 305
 306/**
 307 * transport_alloc_session_tags - allocate target driver private data
 308 * @se_sess:  Session pointer.
 309 * @tag_num:  Maximum number of in-flight commands between initiator and target.
 310 * @tag_size: Size in bytes of the private data a target driver associates with
 311 *	      each command.
 312 */
 313int transport_alloc_session_tags(struct se_session *se_sess,
 314			         unsigned int tag_num, unsigned int tag_size)
 315{
 316	int rc;
 317
 318	se_sess->sess_cmd_map = kvcalloc(tag_size, tag_num,
 319					 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
 320	if (!se_sess->sess_cmd_map) {
 321		pr_err("Unable to allocate se_sess->sess_cmd_map\n");
 322		return -ENOMEM;
 323	}
 324
 325	rc = sbitmap_queue_init_node(&se_sess->sess_tag_pool, tag_num, -1,
 326			false, GFP_KERNEL, NUMA_NO_NODE);
 327	if (rc < 0) {
 328		pr_err("Unable to init se_sess->sess_tag_pool,"
 329			" tag_num: %u\n", tag_num);
 330		kvfree(se_sess->sess_cmd_map);
 331		se_sess->sess_cmd_map = NULL;
 332		return -ENOMEM;
 333	}
 334
 335	return 0;
 336}
 337EXPORT_SYMBOL(transport_alloc_session_tags);
 338
 339/**
 340 * transport_init_session_tags - allocate a session and target driver private data
 341 * @tag_num:  Maximum number of in-flight commands between initiator and target.
 342 * @tag_size: Size in bytes of the private data a target driver associates with
 343 *	      each command.
 344 * @sup_prot_ops: bitmask that defines which T10-PI modes are supported.
 345 */
 346static struct se_session *
 347transport_init_session_tags(unsigned int tag_num, unsigned int tag_size,
 348			    enum target_prot_op sup_prot_ops)
 349{
 350	struct se_session *se_sess;
 351	int rc;
 352
 353	if (tag_num != 0 && !tag_size) {
 354		pr_err("init_session_tags called with percpu-ida tag_num:"
 355		       " %u, but zero tag_size\n", tag_num);
 356		return ERR_PTR(-EINVAL);
 357	}
 358	if (!tag_num && tag_size) {
 359		pr_err("init_session_tags called with percpu-ida tag_size:"
 360		       " %u, but zero tag_num\n", tag_size);
 361		return ERR_PTR(-EINVAL);
 362	}
 363
 364	se_sess = transport_alloc_session(sup_prot_ops);
 365	if (IS_ERR(se_sess))
 366		return se_sess;
 367
 368	rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
 369	if (rc < 0) {
 370		transport_free_session(se_sess);
 371		return ERR_PTR(-ENOMEM);
 372	}
 373
 374	return se_sess;
 375}
 376
 377/*
 378 * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
 379 */
 380void __transport_register_session(
 381	struct se_portal_group *se_tpg,
 382	struct se_node_acl *se_nacl,
 383	struct se_session *se_sess,
 384	void *fabric_sess_ptr)
 385{
 386	const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
 387	unsigned char buf[PR_REG_ISID_LEN];
 388	unsigned long flags;
 389
 390	se_sess->se_tpg = se_tpg;
 391	se_sess->fabric_sess_ptr = fabric_sess_ptr;
 392	/*
 393	 * Used by struct se_node_acl's under ConfigFS to locate active se_session-t
 394	 *
 395	 * Only set for struct se_session's that will actually be moving I/O.
 396	 * eg: *NOT* discovery sessions.
 397	 */
 398	if (se_nacl) {
 399		/*
 400		 *
 401		 * Determine if fabric allows for T10-PI feature bits exposed to
 402		 * initiators for device backends with !dev->dev_attrib.pi_prot_type.
 403		 *
 404		 * If so, then always save prot_type on a per se_node_acl node
 405		 * basis and re-instate the previous sess_prot_type to avoid
 406		 * disabling PI from below any previously initiator side
 407		 * registered LUNs.
 408		 */
 409		if (se_nacl->saved_prot_type)
 410			se_sess->sess_prot_type = se_nacl->saved_prot_type;
 411		else if (tfo->tpg_check_prot_fabric_only)
 412			se_sess->sess_prot_type = se_nacl->saved_prot_type =
 413					tfo->tpg_check_prot_fabric_only(se_tpg);
 414		/*
 415		 * If the fabric module supports an ISID based TransportID,
 416		 * save this value in binary from the fabric I_T Nexus now.
 417		 */
 418		if (se_tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
 419			memset(&buf[0], 0, PR_REG_ISID_LEN);
 420			se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess,
 421					&buf[0], PR_REG_ISID_LEN);
 422			se_sess->sess_bin_isid = get_unaligned_be64(&buf[0]);
 423		}
 424
 425		spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 426		/*
 427		 * The se_nacl->nacl_sess pointer will be set to the
 428		 * last active I_T Nexus for each struct se_node_acl.
 429		 */
 430		se_nacl->nacl_sess = se_sess;
 431
 432		list_add_tail(&se_sess->sess_acl_list,
 433			      &se_nacl->acl_sess_list);
 434		spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 435	}
 436	list_add_tail(&se_sess->sess_list, &se_tpg->tpg_sess_list);
 437
 438	pr_debug("TARGET_CORE[%s]: Registered fabric_sess_ptr: %p\n",
 439		se_tpg->se_tpg_tfo->fabric_name, se_sess->fabric_sess_ptr);
 440}
 441EXPORT_SYMBOL(__transport_register_session);
 442
 443void transport_register_session(
 444	struct se_portal_group *se_tpg,
 445	struct se_node_acl *se_nacl,
 446	struct se_session *se_sess,
 447	void *fabric_sess_ptr)
 448{
 449	unsigned long flags;
 450
 451	spin_lock_irqsave(&se_tpg->session_lock, flags);
 452	__transport_register_session(se_tpg, se_nacl, se_sess, fabric_sess_ptr);
 453	spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 454}
 455EXPORT_SYMBOL(transport_register_session);
 456
 457struct se_session *
 458target_setup_session(struct se_portal_group *tpg,
 459		     unsigned int tag_num, unsigned int tag_size,
 460		     enum target_prot_op prot_op,
 461		     const char *initiatorname, void *private,
 462		     int (*callback)(struct se_portal_group *,
 463				     struct se_session *, void *))
 464{
 465	struct target_cmd_counter *cmd_cnt;
 466	struct se_session *sess;
 467	int rc;
 468
 469	cmd_cnt = target_alloc_cmd_counter();
 470	if (!cmd_cnt)
 471		return ERR_PTR(-ENOMEM);
 472	/*
 473	 * If the fabric driver is using percpu-ida based pre allocation
 474	 * of I/O descriptor tags, go ahead and perform that setup now..
 475	 */
 476	if (tag_num != 0)
 477		sess = transport_init_session_tags(tag_num, tag_size, prot_op);
 478	else
 479		sess = transport_alloc_session(prot_op);
 480
 481	if (IS_ERR(sess)) {
 482		rc = PTR_ERR(sess);
 483		goto free_cnt;
 484	}
 485	sess->cmd_cnt = cmd_cnt;
 486
 487	sess->se_node_acl = core_tpg_check_initiator_node_acl(tpg,
 488					(unsigned char *)initiatorname);
 489	if (!sess->se_node_acl) {
 490		rc = -EACCES;
 491		goto free_sess;
 492	}
 493	/*
 494	 * Go ahead and perform any remaining fabric setup that is
 495	 * required before transport_register_session().
 496	 */
 497	if (callback != NULL) {
 498		rc = callback(tpg, sess, private);
 499		if (rc)
 500			goto free_sess;
 501	}
 502
 503	transport_register_session(tpg, sess->se_node_acl, sess, private);
 504	return sess;
 505
 506free_sess:
 507	transport_free_session(sess);
 508	return ERR_PTR(rc);
 509
 510free_cnt:
 511	target_free_cmd_counter(cmd_cnt);
 512	return ERR_PTR(rc);
 513}
 514EXPORT_SYMBOL(target_setup_session);
 515
 516ssize_t target_show_dynamic_sessions(struct se_portal_group *se_tpg, char *page)
 517{
 518	struct se_session *se_sess;
 519	ssize_t len = 0;
 520
 521	spin_lock_bh(&se_tpg->session_lock);
 522	list_for_each_entry(se_sess, &se_tpg->tpg_sess_list, sess_list) {
 523		if (!se_sess->se_node_acl)
 524			continue;
 525		if (!se_sess->se_node_acl->dynamic_node_acl)
 526			continue;
 527		if (strlen(se_sess->se_node_acl->initiatorname) + 1 + len > PAGE_SIZE)
 528			break;
 529
 530		len += snprintf(page + len, PAGE_SIZE - len, "%s\n",
 531				se_sess->se_node_acl->initiatorname);
 532		len += 1; /* Include NULL terminator */
 533	}
 534	spin_unlock_bh(&se_tpg->session_lock);
 535
 536	return len;
 537}
 538EXPORT_SYMBOL(target_show_dynamic_sessions);
 539
 540static void target_complete_nacl(struct kref *kref)
 541{
 542	struct se_node_acl *nacl = container_of(kref,
 543				struct se_node_acl, acl_kref);
 544	struct se_portal_group *se_tpg = nacl->se_tpg;
 545
 546	if (!nacl->dynamic_stop) {
 547		complete(&nacl->acl_free_comp);
 548		return;
 549	}
 550
 551	mutex_lock(&se_tpg->acl_node_mutex);
 552	list_del_init(&nacl->acl_list);
 553	mutex_unlock(&se_tpg->acl_node_mutex);
 554
 555	core_tpg_wait_for_nacl_pr_ref(nacl);
 556	core_free_device_list_for_node(nacl, se_tpg);
 557	kfree(nacl);
 558}
 559
 560void target_put_nacl(struct se_node_acl *nacl)
 561{
 562	kref_put(&nacl->acl_kref, target_complete_nacl);
 563}
 564EXPORT_SYMBOL(target_put_nacl);
 565
 566void transport_deregister_session_configfs(struct se_session *se_sess)
 567{
 568	struct se_node_acl *se_nacl;
 569	unsigned long flags;
 570	/*
 571	 * Used by struct se_node_acl's under ConfigFS to locate active struct se_session
 572	 */
 573	se_nacl = se_sess->se_node_acl;
 574	if (se_nacl) {
 575		spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 576		if (!list_empty(&se_sess->sess_acl_list))
 577			list_del_init(&se_sess->sess_acl_list);
 578		/*
 579		 * If the session list is empty, then clear the pointer.
 580		 * Otherwise, set the struct se_session pointer from the tail
 581		 * element of the per struct se_node_acl active session list.
 582		 */
 583		if (list_empty(&se_nacl->acl_sess_list))
 584			se_nacl->nacl_sess = NULL;
 585		else {
 586			se_nacl->nacl_sess = container_of(
 587					se_nacl->acl_sess_list.prev,
 588					struct se_session, sess_acl_list);
 589		}
 590		spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 591	}
 592}
 593EXPORT_SYMBOL(transport_deregister_session_configfs);
 594
 595void transport_free_session(struct se_session *se_sess)
 596{
 597	struct se_node_acl *se_nacl = se_sess->se_node_acl;
 598
 599	/*
 600	 * Drop the se_node_acl->nacl_kref obtained from within
 601	 * core_tpg_get_initiator_node_acl().
 602	 */
 603	if (se_nacl) {
 604		struct se_portal_group *se_tpg = se_nacl->se_tpg;
 605		const struct target_core_fabric_ops *se_tfo = se_tpg->se_tpg_tfo;
 606		unsigned long flags;
 607
 608		se_sess->se_node_acl = NULL;
 609
 610		/*
 611		 * Also determine if we need to drop the extra ->cmd_kref if
 612		 * it had been previously dynamically generated, and
 613		 * the endpoint is not caching dynamic ACLs.
 614		 */
 615		mutex_lock(&se_tpg->acl_node_mutex);
 616		if (se_nacl->dynamic_node_acl &&
 617		    !se_tfo->tpg_check_demo_mode_cache(se_tpg)) {
 618			spin_lock_irqsave(&se_nacl->nacl_sess_lock, flags);
 619			if (list_empty(&se_nacl->acl_sess_list))
 620				se_nacl->dynamic_stop = true;
 621			spin_unlock_irqrestore(&se_nacl->nacl_sess_lock, flags);
 622
 623			if (se_nacl->dynamic_stop)
 624				list_del_init(&se_nacl->acl_list);
 625		}
 626		mutex_unlock(&se_tpg->acl_node_mutex);
 627
 628		if (se_nacl->dynamic_stop)
 629			target_put_nacl(se_nacl);
 630
 631		target_put_nacl(se_nacl);
 632	}
 633	if (se_sess->sess_cmd_map) {
 634		sbitmap_queue_free(&se_sess->sess_tag_pool);
 635		kvfree(se_sess->sess_cmd_map);
 636	}
 637	if (se_sess->cmd_cnt)
 638		target_free_cmd_counter(se_sess->cmd_cnt);
 639	kmem_cache_free(se_sess_cache, se_sess);
 640}
 641EXPORT_SYMBOL(transport_free_session);
 642
 643static int target_release_res(struct se_device *dev, void *data)
 644{
 645	struct se_session *sess = data;
 646
 647	if (dev->reservation_holder == sess)
 648		target_release_reservation(dev);
 649	return 0;
 650}
 651
 652void transport_deregister_session(struct se_session *se_sess)
 653{
 654	struct se_portal_group *se_tpg = se_sess->se_tpg;
 655	unsigned long flags;
 656
 657	if (!se_tpg) {
 658		transport_free_session(se_sess);
 659		return;
 660	}
 661
 662	spin_lock_irqsave(&se_tpg->session_lock, flags);
 663	list_del(&se_sess->sess_list);
 664	se_sess->se_tpg = NULL;
 665	se_sess->fabric_sess_ptr = NULL;
 666	spin_unlock_irqrestore(&se_tpg->session_lock, flags);
 667
 668	/*
 669	 * Since the session is being removed, release SPC-2
 670	 * reservations held by the session that is disappearing.
 671	 */
 672	target_for_each_device(target_release_res, se_sess);
 673
 674	pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n",
 675		se_tpg->se_tpg_tfo->fabric_name);
 676	/*
 677	 * If last kref is dropping now for an explicit NodeACL, awake sleeping
 678	 * ->acl_free_comp caller to wakeup configfs se_node_acl->acl_group
 679	 * removal context from within transport_free_session() code.
 680	 *
 681	 * For dynamic ACL, target_put_nacl() uses target_complete_nacl()
 682	 * to release all remaining generate_node_acl=1 created ACL resources.
 683	 */
 684
 685	transport_free_session(se_sess);
 686}
 687EXPORT_SYMBOL(transport_deregister_session);
 688
 689void target_remove_session(struct se_session *se_sess)
 690{
 691	transport_deregister_session_configfs(se_sess);
 692	transport_deregister_session(se_sess);
 693}
 694EXPORT_SYMBOL(target_remove_session);
 695
 696static void target_remove_from_state_list(struct se_cmd *cmd)
 697{
 698	struct se_device *dev = cmd->se_dev;
 699	unsigned long flags;
 700
 701	if (!dev)
 702		return;
 703
 704	spin_lock_irqsave(&dev->queues[cmd->cpuid].lock, flags);
 705	if (cmd->state_active) {
 706		list_del(&cmd->state_list);
 707		cmd->state_active = false;
 708	}
 709	spin_unlock_irqrestore(&dev->queues[cmd->cpuid].lock, flags);
 710}
 711
 712static void target_remove_from_tmr_list(struct se_cmd *cmd)
 713{
 714	struct se_device *dev = NULL;
 715	unsigned long flags;
 716
 717	if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
 718		dev = cmd->se_tmr_req->tmr_dev;
 719
 720	if (dev) {
 721		spin_lock_irqsave(&dev->se_tmr_lock, flags);
 722		if (cmd->se_tmr_req->tmr_dev)
 723			list_del_init(&cmd->se_tmr_req->tmr_list);
 724		spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
 725	}
 726}
 727/*
 728 * This function is called by the target core after the target core has
 729 * finished processing a SCSI command or SCSI TMF. Both the regular command
 730 * processing code and the code for aborting commands can call this
 731 * function. CMD_T_STOP is set if and only if another thread is waiting
 732 * inside transport_wait_for_tasks() for t_transport_stop_comp.
 733 */
 734static int transport_cmd_check_stop_to_fabric(struct se_cmd *cmd)
 735{
 736	unsigned long flags;
 737
 738	spin_lock_irqsave(&cmd->t_state_lock, flags);
 739	/*
 740	 * Determine if frontend context caller is requesting the stopping of
 741	 * this command for frontend exceptions.
 742	 */
 743	if (cmd->transport_state & CMD_T_STOP) {
 744		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
 745			__func__, __LINE__, cmd->tag);
 746
 747		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 748
 749		complete_all(&cmd->t_transport_stop_comp);
 750		return 1;
 751	}
 752	cmd->transport_state &= ~CMD_T_ACTIVE;
 753	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 754
 755	/*
 756	 * Some fabric modules like tcm_loop can release their internally
 757	 * allocated I/O reference and struct se_cmd now.
 758	 *
 759	 * Fabric modules are expected to return '1' here if the se_cmd being
 760	 * passed is released at this point, or zero if not being released.
 761	 */
 762	return cmd->se_tfo->check_stop_free(cmd);
 763}
 764
 765static void transport_lun_remove_cmd(struct se_cmd *cmd)
 766{
 767	struct se_lun *lun = cmd->se_lun;
 768
 769	if (!lun)
 770		return;
 771
 772	target_remove_from_state_list(cmd);
 773	target_remove_from_tmr_list(cmd);
 774
 775	if (cmpxchg(&cmd->lun_ref_active, true, false))
 776		percpu_ref_put(&lun->lun_ref);
 777
 778	/*
 779	 * Clear struct se_cmd->se_lun before the handoff to FE.
 780	 */
 781	cmd->se_lun = NULL;
 782}
 783
 784static void target_complete_failure_work(struct work_struct *work)
 785{
 786	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 787
 788	transport_generic_request_failure(cmd, cmd->sense_reason);
 789}
 790
 791/*
 792 * Used when asking transport to copy Sense Data from the underlying
 793 * Linux/SCSI struct scsi_cmnd
 794 */
 795static unsigned char *transport_get_sense_buffer(struct se_cmd *cmd)
 796{
 797	struct se_device *dev = cmd->se_dev;
 798
 799	WARN_ON(!cmd->se_lun);
 800
 801	if (!dev)
 802		return NULL;
 803
 804	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION)
 805		return NULL;
 806
 807	cmd->scsi_sense_length = TRANSPORT_SENSE_BUFFER;
 808
 809	pr_debug("HBA_[%u]_PLUG[%s]: Requesting sense for SAM STATUS: 0x%02x\n",
 810		dev->se_hba->hba_id, dev->transport->name, cmd->scsi_status);
 811	return cmd->sense_buffer;
 812}
 813
 814void transport_copy_sense_to_cmd(struct se_cmd *cmd, unsigned char *sense)
 815{
 816	unsigned char *cmd_sense_buf;
 817	unsigned long flags;
 818
 819	spin_lock_irqsave(&cmd->t_state_lock, flags);
 820	cmd_sense_buf = transport_get_sense_buffer(cmd);
 821	if (!cmd_sense_buf) {
 822		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 823		return;
 824	}
 825
 826	cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
 827	memcpy(cmd_sense_buf, sense, cmd->scsi_sense_length);
 828	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 829}
 830EXPORT_SYMBOL(transport_copy_sense_to_cmd);
 831
 832static void target_handle_abort(struct se_cmd *cmd)
 833{
 834	bool tas = cmd->transport_state & CMD_T_TAS;
 835	bool ack_kref = cmd->se_cmd_flags & SCF_ACK_KREF;
 836	int ret;
 837
 838	pr_debug("tag %#llx: send_abort_response = %d\n", cmd->tag, tas);
 839
 840	if (tas) {
 841		if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
 842			cmd->scsi_status = SAM_STAT_TASK_ABORTED;
 843			pr_debug("Setting SAM_STAT_TASK_ABORTED status for CDB: 0x%02x, ITT: 0x%08llx\n",
 844				 cmd->t_task_cdb[0], cmd->tag);
 845			trace_target_cmd_complete(cmd);
 846			ret = cmd->se_tfo->queue_status(cmd);
 847			if (ret) {
 848				transport_handle_queue_full(cmd, cmd->se_dev,
 849							    ret, false);
 850				return;
 851			}
 852		} else {
 853			cmd->se_tmr_req->response = TMR_FUNCTION_REJECTED;
 854			cmd->se_tfo->queue_tm_rsp(cmd);
 855		}
 856	} else {
 857		/*
 858		 * Allow the fabric driver to unmap any resources before
 859		 * releasing the descriptor via TFO->release_cmd().
 860		 */
 861		cmd->se_tfo->aborted_task(cmd);
 862		if (ack_kref)
 863			WARN_ON_ONCE(target_put_sess_cmd(cmd) != 0);
 864		/*
 865		 * To do: establish a unit attention condition on the I_T
 866		 * nexus associated with cmd. See also the paragraph "Aborting
 867		 * commands" in SAM.
 868		 */
 869	}
 870
 871	WARN_ON_ONCE(kref_read(&cmd->cmd_kref) == 0);
 872
 873	transport_lun_remove_cmd(cmd);
 874
 875	transport_cmd_check_stop_to_fabric(cmd);
 876}
 877
 878static void target_abort_work(struct work_struct *work)
 879{
 880	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
 881
 882	target_handle_abort(cmd);
 883}
 884
 885static bool target_cmd_interrupted(struct se_cmd *cmd)
 886{
 887	int post_ret;
 888
 889	if (cmd->transport_state & CMD_T_ABORTED) {
 890		if (cmd->transport_complete_callback)
 891			cmd->transport_complete_callback(cmd, false, &post_ret);
 892		INIT_WORK(&cmd->work, target_abort_work);
 893		queue_work(target_completion_wq, &cmd->work);
 894		return true;
 895	} else if (cmd->transport_state & CMD_T_STOP) {
 896		if (cmd->transport_complete_callback)
 897			cmd->transport_complete_callback(cmd, false, &post_ret);
 898		complete_all(&cmd->t_transport_stop_comp);
 899		return true;
 900	}
 901
 902	return false;
 903}
 904
 905/* May be called from interrupt context so must not sleep. */
 906void target_complete_cmd_with_sense(struct se_cmd *cmd, u8 scsi_status,
 907				    sense_reason_t sense_reason)
 908{
 909	struct se_wwn *wwn = cmd->se_sess->se_tpg->se_tpg_wwn;
 910	int success, cpu;
 911	unsigned long flags;
 912
 913	if (target_cmd_interrupted(cmd))
 914		return;
 915
 916	cmd->scsi_status = scsi_status;
 917	cmd->sense_reason = sense_reason;
 918
 919	spin_lock_irqsave(&cmd->t_state_lock, flags);
 920	switch (cmd->scsi_status) {
 921	case SAM_STAT_CHECK_CONDITION:
 922		if (cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
 923			success = 1;
 924		else
 925			success = 0;
 926		break;
 927	default:
 928		success = 1;
 929		break;
 930	}
 931
 932	cmd->t_state = TRANSPORT_COMPLETE;
 933	cmd->transport_state |= (CMD_T_COMPLETE | CMD_T_ACTIVE);
 934	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 935
 936	INIT_WORK(&cmd->work, success ? target_complete_ok_work :
 937		  target_complete_failure_work);
 938
 939	if (!wwn || wwn->cmd_compl_affinity == SE_COMPL_AFFINITY_CPUID)
 940		cpu = cmd->cpuid;
 941	else
 942		cpu = wwn->cmd_compl_affinity;
 943
 944	queue_work_on(cpu, target_completion_wq, &cmd->work);
 945}
 946EXPORT_SYMBOL(target_complete_cmd_with_sense);
 947
 948void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status)
 949{
 950	target_complete_cmd_with_sense(cmd, scsi_status, scsi_status ?
 951			      TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE :
 952			      TCM_NO_SENSE);
 953}
 954EXPORT_SYMBOL(target_complete_cmd);
 955
 956void target_set_cmd_data_length(struct se_cmd *cmd, int length)
 957{
 958	if (length < cmd->data_length) {
 959		if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
 960			cmd->residual_count += cmd->data_length - length;
 961		} else {
 962			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
 963			cmd->residual_count = cmd->data_length - length;
 964		}
 965
 966		cmd->data_length = length;
 967	}
 968}
 969EXPORT_SYMBOL(target_set_cmd_data_length);
 970
 971void target_complete_cmd_with_length(struct se_cmd *cmd, u8 scsi_status, int length)
 972{
 973	if (scsi_status == SAM_STAT_GOOD ||
 974	    cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) {
 975		target_set_cmd_data_length(cmd, length);
 976	}
 977
 978	target_complete_cmd(cmd, scsi_status);
 979}
 980EXPORT_SYMBOL(target_complete_cmd_with_length);
 981
 982static void target_add_to_state_list(struct se_cmd *cmd)
 983{
 984	struct se_device *dev = cmd->se_dev;
 985	unsigned long flags;
 986
 987	spin_lock_irqsave(&dev->queues[cmd->cpuid].lock, flags);
 988	if (!cmd->state_active) {
 989		list_add_tail(&cmd->state_list,
 990			      &dev->queues[cmd->cpuid].state_list);
 991		cmd->state_active = true;
 992	}
 993	spin_unlock_irqrestore(&dev->queues[cmd->cpuid].lock, flags);
 994}
 995
 996/*
 997 * Handle QUEUE_FULL / -EAGAIN and -ENOMEM status
 998 */
 999static void transport_write_pending_qf(struct se_cmd *cmd);
1000static void transport_complete_qf(struct se_cmd *cmd);
1001
1002void target_qf_do_work(struct work_struct *work)
1003{
1004	struct se_device *dev = container_of(work, struct se_device,
1005					qf_work_queue);
1006	LIST_HEAD(qf_cmd_list);
1007	struct se_cmd *cmd, *cmd_tmp;
1008
1009	spin_lock_irq(&dev->qf_cmd_lock);
1010	list_splice_init(&dev->qf_cmd_list, &qf_cmd_list);
1011	spin_unlock_irq(&dev->qf_cmd_lock);
1012
1013	list_for_each_entry_safe(cmd, cmd_tmp, &qf_cmd_list, se_qf_node) {
1014		list_del(&cmd->se_qf_node);
1015		atomic_dec_mb(&dev->dev_qf_count);
1016
1017		pr_debug("Processing %s cmd: %p QUEUE_FULL in work queue"
1018			" context: %s\n", cmd->se_tfo->fabric_name, cmd,
1019			(cmd->t_state == TRANSPORT_COMPLETE_QF_OK) ? "COMPLETE_OK" :
1020			(cmd->t_state == TRANSPORT_COMPLETE_QF_WP) ? "WRITE_PENDING"
1021			: "UNKNOWN");
1022
1023		if (cmd->t_state == TRANSPORT_COMPLETE_QF_WP)
1024			transport_write_pending_qf(cmd);
1025		else if (cmd->t_state == TRANSPORT_COMPLETE_QF_OK ||
1026			 cmd->t_state == TRANSPORT_COMPLETE_QF_ERR)
1027			transport_complete_qf(cmd);
1028	}
1029}
1030
1031unsigned char *transport_dump_cmd_direction(struct se_cmd *cmd)
1032{
1033	switch (cmd->data_direction) {
1034	case DMA_NONE:
1035		return "NONE";
1036	case DMA_FROM_DEVICE:
1037		return "READ";
1038	case DMA_TO_DEVICE:
1039		return "WRITE";
1040	case DMA_BIDIRECTIONAL:
1041		return "BIDI";
1042	default:
1043		break;
1044	}
1045
1046	return "UNKNOWN";
1047}
1048
1049void transport_dump_dev_state(
1050	struct se_device *dev,
1051	char *b,
1052	int *bl)
1053{
1054	*bl += sprintf(b + *bl, "Status: ");
1055	if (dev->export_count)
1056		*bl += sprintf(b + *bl, "ACTIVATED");
1057	else
1058		*bl += sprintf(b + *bl, "DEACTIVATED");
1059
1060	*bl += sprintf(b + *bl, "  Max Queue Depth: %d", dev->queue_depth);
1061	*bl += sprintf(b + *bl, "  SectorSize: %u  HwMaxSectors: %u\n",
1062		dev->dev_attrib.block_size,
1063		dev->dev_attrib.hw_max_sectors);
1064	*bl += sprintf(b + *bl, "        ");
1065}
1066
1067void transport_dump_vpd_proto_id(
1068	struct t10_vpd *vpd,
1069	unsigned char *p_buf,
1070	int p_buf_len)
1071{
1072	unsigned char buf[VPD_TMP_BUF_SIZE];
1073	int len;
1074
1075	memset(buf, 0, VPD_TMP_BUF_SIZE);
1076	len = sprintf(buf, "T10 VPD Protocol Identifier: ");
1077
1078	switch (vpd->protocol_identifier) {
1079	case 0x00:
1080		sprintf(buf+len, "Fibre Channel\n");
1081		break;
1082	case 0x10:
1083		sprintf(buf+len, "Parallel SCSI\n");
1084		break;
1085	case 0x20:
1086		sprintf(buf+len, "SSA\n");
1087		break;
1088	case 0x30:
1089		sprintf(buf+len, "IEEE 1394\n");
1090		break;
1091	case 0x40:
1092		sprintf(buf+len, "SCSI Remote Direct Memory Access"
1093				" Protocol\n");
1094		break;
1095	case 0x50:
1096		sprintf(buf+len, "Internet SCSI (iSCSI)\n");
1097		break;
1098	case 0x60:
1099		sprintf(buf+len, "SAS Serial SCSI Protocol\n");
1100		break;
1101	case 0x70:
1102		sprintf(buf+len, "Automation/Drive Interface Transport"
1103				" Protocol\n");
1104		break;
1105	case 0x80:
1106		sprintf(buf+len, "AT Attachment Interface ATA/ATAPI\n");
1107		break;
1108	default:
1109		sprintf(buf+len, "Unknown 0x%02x\n",
1110				vpd->protocol_identifier);
1111		break;
1112	}
1113
1114	if (p_buf)
1115		strncpy(p_buf, buf, p_buf_len);
1116	else
1117		pr_debug("%s", buf);
1118}
1119
1120void
1121transport_set_vpd_proto_id(struct t10_vpd *vpd, unsigned char *page_83)
1122{
1123	/*
1124	 * Check if the Protocol Identifier Valid (PIV) bit is set..
1125	 *
1126	 * from spc3r23.pdf section 7.5.1
1127	 */
1128	 if (page_83[1] & 0x80) {
1129		vpd->protocol_identifier = (page_83[0] & 0xf0);
1130		vpd->protocol_identifier_set = 1;
1131		transport_dump_vpd_proto_id(vpd, NULL, 0);
1132	}
1133}
1134EXPORT_SYMBOL(transport_set_vpd_proto_id);
1135
1136int transport_dump_vpd_assoc(
1137	struct t10_vpd *vpd,
1138	unsigned char *p_buf,
1139	int p_buf_len)
1140{
1141	unsigned char buf[VPD_TMP_BUF_SIZE];
1142	int ret = 0;
1143	int len;
1144
1145	memset(buf, 0, VPD_TMP_BUF_SIZE);
1146	len = sprintf(buf, "T10 VPD Identifier Association: ");
1147
1148	switch (vpd->association) {
1149	case 0x00:
1150		sprintf(buf+len, "addressed logical unit\n");
1151		break;
1152	case 0x10:
1153		sprintf(buf+len, "target port\n");
1154		break;
1155	case 0x20:
1156		sprintf(buf+len, "SCSI target device\n");
1157		break;
1158	default:
1159		sprintf(buf+len, "Unknown 0x%02x\n", vpd->association);
1160		ret = -EINVAL;
1161		break;
1162	}
1163
1164	if (p_buf)
1165		strncpy(p_buf, buf, p_buf_len);
1166	else
1167		pr_debug("%s", buf);
1168
1169	return ret;
1170}
1171
1172int transport_set_vpd_assoc(struct t10_vpd *vpd, unsigned char *page_83)
1173{
1174	/*
1175	 * The VPD identification association..
1176	 *
1177	 * from spc3r23.pdf Section 7.6.3.1 Table 297
1178	 */
1179	vpd->association = (page_83[1] & 0x30);
1180	return transport_dump_vpd_assoc(vpd, NULL, 0);
1181}
1182EXPORT_SYMBOL(transport_set_vpd_assoc);
1183
1184int transport_dump_vpd_ident_type(
1185	struct t10_vpd *vpd,
1186	unsigned char *p_buf,
1187	int p_buf_len)
1188{
1189	unsigned char buf[VPD_TMP_BUF_SIZE];
1190	int ret = 0;
1191	int len;
1192
1193	memset(buf, 0, VPD_TMP_BUF_SIZE);
1194	len = sprintf(buf, "T10 VPD Identifier Type: ");
1195
1196	switch (vpd->device_identifier_type) {
1197	case 0x00:
1198		sprintf(buf+len, "Vendor specific\n");
1199		break;
1200	case 0x01:
1201		sprintf(buf+len, "T10 Vendor ID based\n");
1202		break;
1203	case 0x02:
1204		sprintf(buf+len, "EUI-64 based\n");
1205		break;
1206	case 0x03:
1207		sprintf(buf+len, "NAA\n");
1208		break;
1209	case 0x04:
1210		sprintf(buf+len, "Relative target port identifier\n");
1211		break;
1212	case 0x08:
1213		sprintf(buf+len, "SCSI name string\n");
1214		break;
1215	default:
1216		sprintf(buf+len, "Unsupported: 0x%02x\n",
1217				vpd->device_identifier_type);
1218		ret = -EINVAL;
1219		break;
1220	}
1221
1222	if (p_buf) {
1223		if (p_buf_len < strlen(buf)+1)
1224			return -EINVAL;
1225		strncpy(p_buf, buf, p_buf_len);
1226	} else {
1227		pr_debug("%s", buf);
1228	}
1229
1230	return ret;
1231}
1232
1233int transport_set_vpd_ident_type(struct t10_vpd *vpd, unsigned char *page_83)
1234{
1235	/*
1236	 * The VPD identifier type..
1237	 *
1238	 * from spc3r23.pdf Section 7.6.3.1 Table 298
1239	 */
1240	vpd->device_identifier_type = (page_83[1] & 0x0f);
1241	return transport_dump_vpd_ident_type(vpd, NULL, 0);
1242}
1243EXPORT_SYMBOL(transport_set_vpd_ident_type);
1244
1245int transport_dump_vpd_ident(
1246	struct t10_vpd *vpd,
1247	unsigned char *p_buf,
1248	int p_buf_len)
1249{
1250	unsigned char buf[VPD_TMP_BUF_SIZE];
1251	int ret = 0;
1252
1253	memset(buf, 0, VPD_TMP_BUF_SIZE);
1254
1255	switch (vpd->device_identifier_code_set) {
1256	case 0x01: /* Binary */
1257		snprintf(buf, sizeof(buf),
1258			"T10 VPD Binary Device Identifier: %s\n",
1259			&vpd->device_identifier[0]);
1260		break;
1261	case 0x02: /* ASCII */
1262		snprintf(buf, sizeof(buf),
1263			"T10 VPD ASCII Device Identifier: %s\n",
1264			&vpd->device_identifier[0]);
1265		break;
1266	case 0x03: /* UTF-8 */
1267		snprintf(buf, sizeof(buf),
1268			"T10 VPD UTF-8 Device Identifier: %s\n",
1269			&vpd->device_identifier[0]);
1270		break;
1271	default:
1272		sprintf(buf, "T10 VPD Device Identifier encoding unsupported:"
1273			" 0x%02x", vpd->device_identifier_code_set);
1274		ret = -EINVAL;
1275		break;
1276	}
1277
1278	if (p_buf)
1279		strncpy(p_buf, buf, p_buf_len);
1280	else
1281		pr_debug("%s", buf);
1282
1283	return ret;
1284}
1285
1286int
1287transport_set_vpd_ident(struct t10_vpd *vpd, unsigned char *page_83)
1288{
1289	static const char hex_str[] = "0123456789abcdef";
1290	int j = 0, i = 4; /* offset to start of the identifier */
1291
1292	/*
1293	 * The VPD Code Set (encoding)
1294	 *
1295	 * from spc3r23.pdf Section 7.6.3.1 Table 296
1296	 */
1297	vpd->device_identifier_code_set = (page_83[0] & 0x0f);
1298	switch (vpd->device_identifier_code_set) {
1299	case 0x01: /* Binary */
1300		vpd->device_identifier[j++] =
1301				hex_str[vpd->device_identifier_type];
1302		while (i < (4 + page_83[3])) {
1303			vpd->device_identifier[j++] =
1304				hex_str[(page_83[i] & 0xf0) >> 4];
1305			vpd->device_identifier[j++] =
1306				hex_str[page_83[i] & 0x0f];
1307			i++;
1308		}
1309		break;
1310	case 0x02: /* ASCII */
1311	case 0x03: /* UTF-8 */
1312		while (i < (4 + page_83[3]))
1313			vpd->device_identifier[j++] = page_83[i++];
1314		break;
1315	default:
1316		break;
1317	}
1318
1319	return transport_dump_vpd_ident(vpd, NULL, 0);
1320}
1321EXPORT_SYMBOL(transport_set_vpd_ident);
1322
1323static sense_reason_t
1324target_check_max_data_sg_nents(struct se_cmd *cmd, struct se_device *dev,
1325			       unsigned int size)
1326{
1327	u32 mtl;
1328
1329	if (!cmd->se_tfo->max_data_sg_nents)
1330		return TCM_NO_SENSE;
1331	/*
1332	 * Check if fabric enforced maximum SGL entries per I/O descriptor
1333	 * exceeds se_cmd->data_length.  If true, set SCF_UNDERFLOW_BIT +
1334	 * residual_count and reduce original cmd->data_length to maximum
1335	 * length based on single PAGE_SIZE entry scatter-lists.
1336	 */
1337	mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE);
1338	if (cmd->data_length > mtl) {
1339		/*
1340		 * If an existing CDB overflow is present, calculate new residual
1341		 * based on CDB size minus fabric maximum transfer length.
1342		 *
1343		 * If an existing CDB underflow is present, calculate new residual
1344		 * based on original cmd->data_length minus fabric maximum transfer
1345		 * length.
1346		 *
1347		 * Otherwise, set the underflow residual based on cmd->data_length
1348		 * minus fabric maximum transfer length.
1349		 */
1350		if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1351			cmd->residual_count = (size - mtl);
1352		} else if (cmd->se_cmd_flags & SCF_UNDERFLOW_BIT) {
1353			u32 orig_dl = size + cmd->residual_count;
1354			cmd->residual_count = (orig_dl - mtl);
1355		} else {
1356			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1357			cmd->residual_count = (cmd->data_length - mtl);
1358		}
1359		cmd->data_length = mtl;
1360		/*
1361		 * Reset sbc_check_prot() calculated protection payload
1362		 * length based upon the new smaller MTL.
1363		 */
1364		if (cmd->prot_length) {
1365			u32 sectors = (mtl / dev->dev_attrib.block_size);
1366			cmd->prot_length = dev->prot_length * sectors;
1367		}
1368	}
1369	return TCM_NO_SENSE;
1370}
1371
1372/**
1373 * target_cmd_size_check - Check whether there will be a residual.
1374 * @cmd: SCSI command.
1375 * @size: Data buffer size derived from CDB. The data buffer size provided by
1376 *   the SCSI transport driver is available in @cmd->data_length.
1377 *
1378 * Compare the data buffer size from the CDB with the data buffer limit from the transport
1379 * header. Set @cmd->residual_count and SCF_OVERFLOW_BIT or SCF_UNDERFLOW_BIT if necessary.
1380 *
1381 * Note: target drivers set @cmd->data_length by calling __target_init_cmd().
1382 *
1383 * Return: TCM_NO_SENSE
1384 */
1385sense_reason_t
1386target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
1387{
1388	struct se_device *dev = cmd->se_dev;
1389
1390	if (cmd->unknown_data_length) {
1391		cmd->data_length = size;
1392	} else if (size != cmd->data_length) {
1393		pr_warn_ratelimited("TARGET_CORE[%s]: Expected Transfer Length:"
1394			" %u does not match SCSI CDB Length: %u for SAM Opcode:"
1395			" 0x%02x\n", cmd->se_tfo->fabric_name,
1396				cmd->data_length, size, cmd->t_task_cdb[0]);
1397		/*
1398		 * For READ command for the overflow case keep the existing
1399		 * fabric provided ->data_length. Otherwise for the underflow
1400		 * case, reset ->data_length to the smaller SCSI expected data
1401		 * transfer length.
1402		 */
1403		if (size > cmd->data_length) {
1404			cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
1405			cmd->residual_count = (size - cmd->data_length);
1406		} else {
1407			cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
1408			cmd->residual_count = (cmd->data_length - size);
1409			/*
1410			 * Do not truncate ->data_length for WRITE command to
1411			 * dump all payload
1412			 */
1413			if (cmd->data_direction == DMA_FROM_DEVICE) {
1414				cmd->data_length = size;
1415			}
1416		}
1417
1418		if (cmd->data_direction == DMA_TO_DEVICE) {
1419			if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1420				pr_err_ratelimited("Rejecting underflow/overflow"
1421						   " for WRITE data CDB\n");
1422				return TCM_INVALID_FIELD_IN_COMMAND_IU;
1423			}
1424			/*
1425			 * Some fabric drivers like iscsi-target still expect to
1426			 * always reject overflow writes.  Reject this case until
1427			 * full fabric driver level support for overflow writes
1428			 * is introduced tree-wide.
1429			 */
1430			if (size > cmd->data_length) {
1431				pr_err_ratelimited("Rejecting overflow for"
1432						   " WRITE control CDB\n");
1433				return TCM_INVALID_CDB_FIELD;
1434			}
1435		}
1436	}
1437
1438	return target_check_max_data_sg_nents(cmd, dev, size);
1439
1440}
1441
1442/*
1443 * Used by fabric modules containing a local struct se_cmd within their
1444 * fabric dependent per I/O descriptor.
1445 *
1446 * Preserves the value of @cmd->tag.
1447 */
1448void __target_init_cmd(struct se_cmd *cmd,
1449		       const struct target_core_fabric_ops *tfo,
1450		       struct se_session *se_sess, u32 data_length,
1451		       int data_direction, int task_attr,
1452		       unsigned char *sense_buffer, u64 unpacked_lun,
1453		       struct target_cmd_counter *cmd_cnt)
1454{
1455	INIT_LIST_HEAD(&cmd->se_delayed_node);
1456	INIT_LIST_HEAD(&cmd->se_qf_node);
1457	INIT_LIST_HEAD(&cmd->state_list);
1458	init_completion(&cmd->t_transport_stop_comp);
1459	cmd->free_compl = NULL;
1460	cmd->abrt_compl = NULL;
1461	spin_lock_init(&cmd->t_state_lock);
1462	INIT_WORK(&cmd->work, NULL);
1463	kref_init(&cmd->cmd_kref);
1464
1465	cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1466	cmd->se_tfo = tfo;
1467	cmd->se_sess = se_sess;
1468	cmd->data_length = data_length;
1469	cmd->data_direction = data_direction;
1470	cmd->sam_task_attr = task_attr;
1471	cmd->sense_buffer = sense_buffer;
1472	cmd->orig_fe_lun = unpacked_lun;
1473	cmd->cmd_cnt = cmd_cnt;
1474
1475	if (!(cmd->se_cmd_flags & SCF_USE_CPUID))
1476		cmd->cpuid = raw_smp_processor_id();
1477
1478	cmd->state_active = false;
1479}
1480EXPORT_SYMBOL(__target_init_cmd);
1481
1482static sense_reason_t
1483transport_check_alloc_task_attr(struct se_cmd *cmd)
1484{
1485	struct se_device *dev = cmd->se_dev;
1486
1487	/*
1488	 * Check if SAM Task Attribute emulation is enabled for this
1489	 * struct se_device storage object
1490	 */
1491	if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
1492		return 0;
1493
1494	if (cmd->sam_task_attr == TCM_ACA_TAG) {
1495		pr_debug("SAM Task Attribute ACA"
1496			" emulation is not supported\n");
1497		return TCM_INVALID_CDB_FIELD;
1498	}
1499
1500	return 0;
1501}
1502
1503sense_reason_t
1504target_cmd_init_cdb(struct se_cmd *cmd, unsigned char *cdb, gfp_t gfp)
1505{
1506	sense_reason_t ret;
1507
1508	/*
1509	 * Ensure that the received CDB is less than the max (252 + 8) bytes
1510	 * for VARIABLE_LENGTH_CMD
1511	 */
1512	if (scsi_command_size(cdb) > SCSI_MAX_VARLEN_CDB_SIZE) {
1513		pr_err("Received SCSI CDB with command_size: %d that"
1514			" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1515			scsi_command_size(cdb), SCSI_MAX_VARLEN_CDB_SIZE);
1516		ret = TCM_INVALID_CDB_FIELD;
1517		goto err;
1518	}
1519	/*
1520	 * If the received CDB is larger than TCM_MAX_COMMAND_SIZE,
1521	 * allocate the additional extended CDB buffer now..  Otherwise
1522	 * setup the pointer from __t_task_cdb to t_task_cdb.
1523	 */
1524	if (scsi_command_size(cdb) > sizeof(cmd->__t_task_cdb)) {
1525		cmd->t_task_cdb = kzalloc(scsi_command_size(cdb), gfp);
1526		if (!cmd->t_task_cdb) {
1527			cmd->t_task_cdb = &cmd->__t_task_cdb[0];
1528			pr_err("Unable to allocate cmd->t_task_cdb"
1529				" %u > sizeof(cmd->__t_task_cdb): %lu ops\n",
1530				scsi_command_size(cdb),
1531				(unsigned long)sizeof(cmd->__t_task_cdb));
1532			ret = TCM_OUT_OF_RESOURCES;
1533			goto err;
1534		}
1535	}
1536	/*
1537	 * Copy the original CDB into cmd->
1538	 */
1539	memcpy(cmd->t_task_cdb, cdb, scsi_command_size(cdb));
1540
1541	trace_target_sequencer_start(cmd);
1542	return 0;
1543
1544err:
1545	/*
1546	 * Copy the CDB here to allow trace_target_cmd_complete() to
1547	 * print the cdb to the trace buffers.
1548	 */
1549	memcpy(cmd->t_task_cdb, cdb, min(scsi_command_size(cdb),
1550					 (unsigned int)TCM_MAX_COMMAND_SIZE));
1551	return ret;
1552}
1553EXPORT_SYMBOL(target_cmd_init_cdb);
1554
1555sense_reason_t
1556target_cmd_parse_cdb(struct se_cmd *cmd)
1557{
1558	struct se_device *dev = cmd->se_dev;
1559	sense_reason_t ret;
1560
1561	ret = dev->transport->parse_cdb(cmd);
1562	if (ret == TCM_UNSUPPORTED_SCSI_OPCODE)
1563		pr_debug_ratelimited("%s/%s: Unsupported SCSI Opcode 0x%02x, sending CHECK_CONDITION.\n",
1564				     cmd->se_tfo->fabric_name,
1565				     cmd->se_sess->se_node_acl->initiatorname,
1566				     cmd->t_task_cdb[0]);
1567	if (ret)
1568		return ret;
1569
1570	ret = transport_check_alloc_task_attr(cmd);
1571	if (ret)
1572		return ret;
1573
1574	cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
1575	/*
1576	 * If this is the xcopy_lun then we won't have lun_stats since we
1577	 * can't export them.
1578	 */
1579	if (cmd->se_lun->lun_stats)
1580		this_cpu_inc(cmd->se_lun->lun_stats->cmd_pdus);
1581	return 0;
1582}
1583EXPORT_SYMBOL(target_cmd_parse_cdb);
1584
1585static int __target_submit(struct se_cmd *cmd)
1586{
1587	sense_reason_t ret;
1588
1589	might_sleep();
1590
1591	/*
1592	 * Check if we need to delay processing because of ALUA
1593	 * Active/NonOptimized primary access state..
1594	 */
1595	core_alua_check_nonop_delay(cmd);
1596
1597	if (cmd->t_data_nents != 0) {
1598		/*
1599		 * This is primarily a hack for udev and tcm loop which sends
1600		 * INQUIRYs with a single page and expects the data to be
1601		 * cleared.
1602		 */
1603		if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) &&
1604		    cmd->data_direction == DMA_FROM_DEVICE) {
1605			struct scatterlist *sgl = cmd->t_data_sg;
1606			unsigned char *buf = NULL;
1607
1608			BUG_ON(!sgl);
1609
1610			buf = kmap_local_page(sg_page(sgl));
1611			if (buf) {
1612				memset(buf + sgl->offset, 0, sgl->length);
1613				kunmap_local(buf);
1614			}
1615		}
1616	}
1617
1618	if (!cmd->se_lun) {
1619		dump_stack();
1620		pr_err("cmd->se_lun is NULL\n");
1621		return -EINVAL;
1622	}
1623
1624	/*
1625	 * Set TRANSPORT_NEW_CMD state and CMD_T_ACTIVE to ensure that
1626	 * outstanding descriptors are handled correctly during shutdown via
1627	 * transport_wait_for_tasks()
1628	 *
1629	 * Also, we don't take cmd->t_state_lock here as we only expect
1630	 * this to be called for initial descriptor submission.
1631	 */
1632	cmd->t_state = TRANSPORT_NEW_CMD;
1633	cmd->transport_state |= CMD_T_ACTIVE;
1634
1635	/*
1636	 * transport_generic_new_cmd() is already handling QUEUE_FULL,
1637	 * so follow TRANSPORT_NEW_CMD processing thread context usage
1638	 * and call transport_generic_request_failure() if necessary..
1639	 */
1640	ret = transport_generic_new_cmd(cmd);
1641	if (ret)
1642		transport_generic_request_failure(cmd, ret);
1643	return 0;
1644}
1645
1646sense_reason_t
1647transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
1648		u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
1649{
1650	if (!sgl || !sgl_count)
1651		return 0;
1652
1653	/*
1654	 * Reject SCSI data overflow with map_mem_to_cmd() as incoming
1655	 * scatterlists already have been set to follow what the fabric
1656	 * passes for the original expected data transfer length.
1657	 */
1658	if (cmd->se_cmd_flags & SCF_OVERFLOW_BIT) {
1659		pr_warn("Rejecting SCSI DATA overflow for fabric using"
1660			" SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC\n");
1661		return TCM_INVALID_CDB_FIELD;
1662	}
1663
1664	cmd->t_data_sg = sgl;
1665	cmd->t_data_nents = sgl_count;
1666	cmd->t_bidi_data_sg = sgl_bidi;
1667	cmd->t_bidi_data_nents = sgl_bidi_count;
1668
1669	cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1670	return 0;
1671}
1672
1673/**
1674 * target_init_cmd - initialize se_cmd
1675 * @se_cmd: command descriptor to init
1676 * @se_sess: associated se_sess for endpoint
1677 * @sense: pointer to SCSI sense buffer
1678 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1679 * @data_length: fabric expected data transfer length
1680 * @task_attr: SAM task attribute
1681 * @data_dir: DMA data direction
1682 * @flags: flags for command submission from target_sc_flags_tables
1683 *
1684 * Task tags are supported if the caller has set @se_cmd->tag.
1685 *
1686 * Returns:
1687 *	- less than zero to signal active I/O shutdown failure.
1688 *	- zero on success.
1689 *
1690 * If the fabric driver calls target_stop_session, then it must check the
1691 * return code and handle failures. This will never fail for other drivers,
1692 * and the return code can be ignored.
1693 */
1694int target_init_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1695		    unsigned char *sense, u64 unpacked_lun,
1696		    u32 data_length, int task_attr, int data_dir, int flags)
1697{
1698	struct se_portal_group *se_tpg;
1699
1700	se_tpg = se_sess->se_tpg;
1701	BUG_ON(!se_tpg);
1702	BUG_ON(se_cmd->se_tfo || se_cmd->se_sess);
1703
1704	if (flags & TARGET_SCF_USE_CPUID)
1705		se_cmd->se_cmd_flags |= SCF_USE_CPUID;
1706	/*
1707	 * Signal bidirectional data payloads to target-core
1708	 */
1709	if (flags & TARGET_SCF_BIDI_OP)
1710		se_cmd->se_cmd_flags |= SCF_BIDI;
1711
1712	if (flags & TARGET_SCF_UNKNOWN_SIZE)
1713		se_cmd->unknown_data_length = 1;
1714	/*
1715	 * Initialize se_cmd for target operation.  From this point
1716	 * exceptions are handled by sending exception status via
1717	 * target_core_fabric_ops->queue_status() callback
1718	 */
1719	__target_init_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, data_length,
1720			  data_dir, task_attr, sense, unpacked_lun,
1721			  se_sess->cmd_cnt);
1722
1723	/*
1724	 * Obtain struct se_cmd->cmd_kref reference. A second kref_get here is
1725	 * necessary for fabrics using TARGET_SCF_ACK_KREF that expect a second
1726	 * kref_put() to happen during fabric packet acknowledgement.
1727	 */
1728	return target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
1729}
1730EXPORT_SYMBOL_GPL(target_init_cmd);
1731
1732/**
1733 * target_submit_prep - prepare cmd for submission
1734 * @se_cmd: command descriptor to prep
1735 * @cdb: pointer to SCSI CDB
1736 * @sgl: struct scatterlist memory for unidirectional mapping
1737 * @sgl_count: scatterlist count for unidirectional mapping
1738 * @sgl_bidi: struct scatterlist memory for bidirectional READ mapping
1739 * @sgl_bidi_count: scatterlist count for bidirectional READ mapping
1740 * @sgl_prot: struct scatterlist memory protection information
1741 * @sgl_prot_count: scatterlist count for protection information
1742 * @gfp: gfp allocation type
1743 *
1744 * Returns:
1745 *	- less than zero to signal failure.
1746 *	- zero on success.
1747 *
1748 * If failure is returned, lio will the callers queue_status to complete
1749 * the cmd.
1750 */
1751int target_submit_prep(struct se_cmd *se_cmd, unsigned char *cdb,
1752		       struct scatterlist *sgl, u32 sgl_count,
1753		       struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
1754		       struct scatterlist *sgl_prot, u32 sgl_prot_count,
1755		       gfp_t gfp)
1756{
1757	sense_reason_t rc;
1758
1759	rc = target_cmd_init_cdb(se_cmd, cdb, gfp);
1760	if (rc)
1761		goto send_cc_direct;
1762
1763	/*
1764	 * Locate se_lun pointer and attach it to struct se_cmd
1765	 */
1766	rc = transport_lookup_cmd_lun(se_cmd);
1767	if (rc)
1768		goto send_cc_direct;
1769
1770	rc = target_cmd_parse_cdb(se_cmd);
1771	if (rc != 0)
1772		goto generic_fail;
1773
1774	/*
1775	 * Save pointers for SGLs containing protection information,
1776	 * if present.
1777	 */
1778	if (sgl_prot_count) {
1779		se_cmd->t_prot_sg = sgl_prot;
1780		se_cmd->t_prot_nents = sgl_prot_count;
1781		se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC;
1782	}
1783
1784	/*
1785	 * When a non zero sgl_count has been passed perform SGL passthrough
1786	 * mapping for pre-allocated fabric memory instead of having target
1787	 * core perform an internal SGL allocation..
1788	 */
1789	if (sgl_count != 0) {
1790		BUG_ON(!sgl);
1791
1792		rc = transport_generic_map_mem_to_cmd(se_cmd, sgl, sgl_count,
1793				sgl_bidi, sgl_bidi_count);
1794		if (rc != 0)
1795			goto generic_fail;
1796	}
1797
1798	return 0;
1799
1800send_cc_direct:
1801	transport_send_check_condition_and_sense(se_cmd, rc, 0);
1802	target_put_sess_cmd(se_cmd);
1803	return -EIO;
1804
1805generic_fail:
1806	transport_generic_request_failure(se_cmd, rc);
1807	return -EIO;
1808}
1809EXPORT_SYMBOL_GPL(target_submit_prep);
1810
1811/**
1812 * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd
1813 *
1814 * @se_cmd: command descriptor to submit
1815 * @se_sess: associated se_sess for endpoint
1816 * @cdb: pointer to SCSI CDB
1817 * @sense: pointer to SCSI sense buffer
1818 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1819 * @data_length: fabric expected data transfer length
1820 * @task_attr: SAM task attribute
1821 * @data_dir: DMA data direction
1822 * @flags: flags for command submission from target_sc_flags_tables
1823 *
1824 * Task tags are supported if the caller has set @se_cmd->tag.
1825 *
1826 * This may only be called from process context, and also currently
1827 * assumes internal allocation of fabric payload buffer by target-core.
1828 *
1829 * It also assumes interal target core SGL memory allocation.
1830 *
1831 * This function must only be used by drivers that do their own
1832 * sync during shutdown and does not use target_stop_session. If there
1833 * is a failure this function will call into the fabric driver's
1834 * queue_status with a CHECK_CONDITION.
1835 */
1836void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
1837		unsigned char *cdb, unsigned char *sense, u64 unpacked_lun,
1838		u32 data_length, int task_attr, int data_dir, int flags)
1839{
1840	int rc;
1841
1842	rc = target_init_cmd(se_cmd, se_sess, sense, unpacked_lun, data_length,
1843			     task_attr, data_dir, flags);
1844	WARN(rc, "Invalid target_submit_cmd use. Driver must not use target_stop_session or call target_init_cmd directly.\n");
1845	if (rc)
1846		return;
1847
1848	if (target_submit_prep(se_cmd, cdb, NULL, 0, NULL, 0, NULL, 0,
1849			       GFP_KERNEL))
1850		return;
1851
1852	target_submit(se_cmd);
1853}
1854EXPORT_SYMBOL(target_submit_cmd);
1855
1856
1857static struct se_dev_plug *target_plug_device(struct se_device *se_dev)
1858{
1859	struct se_dev_plug *se_plug;
1860
1861	if (!se_dev->transport->plug_device)
1862		return NULL;
1863
1864	se_plug = se_dev->transport->plug_device(se_dev);
1865	if (!se_plug)
1866		return NULL;
1867
1868	se_plug->se_dev = se_dev;
1869	/*
1870	 * We have a ref to the lun at this point, but the cmds could
1871	 * complete before we unplug, so grab a ref to the se_device so we
1872	 * can call back into the backend.
1873	 */
1874	config_group_get(&se_dev->dev_group);
1875	return se_plug;
1876}
1877
1878static void target_unplug_device(struct se_dev_plug *se_plug)
1879{
1880	struct se_device *se_dev = se_plug->se_dev;
1881
1882	se_dev->transport->unplug_device(se_plug);
1883	config_group_put(&se_dev->dev_group);
1884}
1885
1886void target_queued_submit_work(struct work_struct *work)
1887{
1888	struct se_cmd_queue *sq = container_of(work, struct se_cmd_queue, work);
1889	struct se_cmd *se_cmd, *next_cmd;
1890	struct se_dev_plug *se_plug = NULL;
1891	struct se_device *se_dev = NULL;
1892	struct llist_node *cmd_list;
1893
1894	cmd_list = llist_del_all(&sq->cmd_list);
1895	if (!cmd_list)
1896		/* Previous call took what we were queued to submit */
1897		return;
1898
1899	cmd_list = llist_reverse_order(cmd_list);
1900	llist_for_each_entry_safe(se_cmd, next_cmd, cmd_list, se_cmd_list) {
1901		if (!se_dev) {
1902			se_dev = se_cmd->se_dev;
1903			se_plug = target_plug_device(se_dev);
1904		}
1905
1906		__target_submit(se_cmd);
1907	}
1908
1909	if (se_plug)
1910		target_unplug_device(se_plug);
1911}
1912
1913/**
1914 * target_queue_submission - queue the cmd to run on the LIO workqueue
1915 * @se_cmd: command descriptor to submit
1916 */
1917static void target_queue_submission(struct se_cmd *se_cmd)
1918{
1919	struct se_device *se_dev = se_cmd->se_dev;
1920	int cpu = se_cmd->cpuid;
1921	struct se_cmd_queue *sq;
1922
1923	sq = &se_dev->queues[cpu].sq;
1924	llist_add(&se_cmd->se_cmd_list, &sq->cmd_list);
1925	queue_work_on(cpu, target_submission_wq, &sq->work);
1926}
1927
1928/**
1929 * target_submit - perform final initialization and submit cmd to LIO core
1930 * @se_cmd: command descriptor to submit
1931 *
1932 * target_submit_prep or something similar must have been called on the cmd,
1933 * and this must be called from process context.
1934 */
1935int target_submit(struct se_cmd *se_cmd)
1936{
1937	const struct target_core_fabric_ops *tfo = se_cmd->se_sess->se_tpg->se_tpg_tfo;
1938	struct se_dev_attrib *da = &se_cmd->se_dev->dev_attrib;
1939	u8 submit_type;
1940
1941	if (da->submit_type == TARGET_FABRIC_DEFAULT_SUBMIT)
1942		submit_type = tfo->default_submit_type;
1943	else if (da->submit_type == TARGET_DIRECT_SUBMIT &&
1944		 tfo->direct_submit_supp)
1945		submit_type = TARGET_DIRECT_SUBMIT;
1946	else
1947		submit_type = TARGET_QUEUE_SUBMIT;
1948
1949	if (submit_type == TARGET_DIRECT_SUBMIT)
1950		return __target_submit(se_cmd);
1951
1952	target_queue_submission(se_cmd);
1953	return 0;
1954}
1955EXPORT_SYMBOL_GPL(target_submit);
1956
1957static void target_complete_tmr_failure(struct work_struct *work)
1958{
1959	struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
1960
1961	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
1962	se_cmd->se_tfo->queue_tm_rsp(se_cmd);
1963
1964	transport_lun_remove_cmd(se_cmd);
1965	transport_cmd_check_stop_to_fabric(se_cmd);
1966}
1967
1968/**
1969 * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
1970 *                     for TMR CDBs
1971 *
1972 * @se_cmd: command descriptor to submit
1973 * @se_sess: associated se_sess for endpoint
1974 * @sense: pointer to SCSI sense buffer
1975 * @unpacked_lun: unpacked LUN to reference for struct se_lun
1976 * @fabric_tmr_ptr: fabric context for TMR req
1977 * @tm_type: Type of TM request
1978 * @gfp: gfp type for caller
1979 * @tag: referenced task tag for TMR_ABORT_TASK
1980 * @flags: submit cmd flags
1981 *
1982 * Callable from all contexts.
1983 **/
1984
1985int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
1986		unsigned char *sense, u64 unpacked_lun,
1987		void *fabric_tmr_ptr, unsigned char tm_type,
1988		gfp_t gfp, u64 tag, int flags)
1989{
1990	struct se_portal_group *se_tpg;
1991	int ret;
1992
1993	se_tpg = se_sess->se_tpg;
1994	BUG_ON(!se_tpg);
1995
1996	__target_init_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
1997			  0, DMA_NONE, TCM_SIMPLE_TAG, sense, unpacked_lun,
1998			  se_sess->cmd_cnt);
1999	/*
2000	 * FIXME: Currently expect caller to handle se_cmd->se_tmr_req
2001	 * allocation failure.
2002	 */
2003	ret = core_tmr_alloc_req(se_cmd, fabric_tmr_ptr, tm_type, gfp);
2004	if (ret < 0)
2005		return -ENOMEM;
2006
2007	if (tm_type == TMR_ABORT_TASK)
2008		se_cmd->se_tmr_req->ref_task_tag = tag;
2009
2010	/* See target_submit_cmd for commentary */
2011	ret = target_get_sess_cmd(se_cmd, flags & TARGET_SCF_ACK_KREF);
2012	if (ret) {
2013		core_tmr_release_req(se_cmd->se_tmr_req);
2014		return ret;
2015	}
2016
2017	ret = transport_lookup_tmr_lun(se_cmd);
2018	if (ret)
2019		goto failure;
2020
2021	transport_generic_handle_tmr(se_cmd);
2022	return 0;
2023
2024	/*
2025	 * For callback during failure handling, push this work off
2026	 * to process context with TMR_LUN_DOES_NOT_EXIST status.
2027	 */
2028failure:
2029	INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
2030	schedule_work(&se_cmd->work);
2031	return 0;
2032}
2033EXPORT_SYMBOL(target_submit_tmr);
2034
2035/*
2036 * Handle SAM-esque emulation for generic transport request failures.
2037 */
2038void transport_generic_request_failure(struct se_cmd *cmd,
2039		sense_reason_t sense_reason)
2040{
2041	int ret = 0, post_ret;
2042
2043	pr_debug("-----[ Storage Engine Exception; sense_reason %d\n",
2044		 sense_reason);
2045	target_show_cmd("-----[ ", cmd);
2046
2047	/*
2048	 * For SAM Task Attribute emulation for failed struct se_cmd
2049	 */
2050	transport_complete_task_attr(cmd);
2051
2052	if (cmd->transport_complete_callback)
2053		cmd->transport_complete_callback(cmd, false, &post_ret);
2054
2055	if (cmd->transport_state & CMD_T_ABORTED) {
2056		INIT_WORK(&cmd->work, target_abort_work);
2057		queue_work(target_completion_wq, &cmd->work);
2058		return;
2059	}
2060
2061	switch (sense_reason) {
2062	case TCM_NON_EXISTENT_LUN:
2063	case TCM_UNSUPPORTED_SCSI_OPCODE:
2064	case TCM_INVALID_CDB_FIELD:
2065	case TCM_INVALID_PARAMETER_LIST:
2066	case TCM_PARAMETER_LIST_LENGTH_ERROR:
2067	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
2068	case TCM_UNKNOWN_MODE_PAGE:
2069	case TCM_WRITE_PROTECTED:
2070	case TCM_ADDRESS_OUT_OF_RANGE:
2071	case TCM_CHECK_CONDITION_ABORT_CMD:
2072	case TCM_CHECK_CONDITION_UNIT_ATTENTION:
2073	case TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED:
2074	case TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED:
2075	case TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED:
2076	case TCM_COPY_TARGET_DEVICE_NOT_REACHABLE:
2077	case TCM_TOO_MANY_TARGET_DESCS:
2078	case TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE:
2079	case TCM_TOO_MANY_SEGMENT_DESCS:
2080	case TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE:
2081	case TCM_INVALID_FIELD_IN_COMMAND_IU:
2082	case TCM_ALUA_TG_PT_STANDBY:
2083	case TCM_ALUA_TG_PT_UNAVAILABLE:
2084	case TCM_ALUA_STATE_TRANSITION:
2085	case TCM_ALUA_OFFLINE:
2086		break;
2087	case TCM_OUT_OF_RESOURCES:
2088		cmd->scsi_status = SAM_STAT_TASK_SET_FULL;
2089		goto queue_status;
2090	case TCM_LUN_BUSY:
2091		cmd->scsi_status = SAM_STAT_BUSY;
2092		goto queue_status;
2093	case TCM_RESERVATION_CONFLICT:
2094		/*
2095		 * No SENSE Data payload for this case, set SCSI Status
2096		 * and queue the response to $FABRIC_MOD.
2097		 *
2098		 * Uses linux/include/scsi/scsi.h SAM status codes defs
2099		 */
2100		cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
2101		/*
2102		 * For UA Interlock Code 11b, a RESERVATION CONFLICT will
2103		 * establish a UNIT ATTENTION with PREVIOUS RESERVATION
2104		 * CONFLICT STATUS.
2105		 *
2106		 * See spc4r17, section 7.4.6 Control Mode Page, Table 349
2107		 */
2108		if (cmd->se_sess &&
2109		    cmd->se_dev->dev_attrib.emulate_ua_intlck_ctrl
2110					== TARGET_UA_INTLCK_CTRL_ESTABLISH_UA) {
2111			target_ua_allocate_lun(cmd->se_sess->se_node_acl,
2112					       cmd->orig_fe_lun, 0x2C,
2113					ASCQ_2CH_PREVIOUS_RESERVATION_CONFLICT_STATUS);
2114		}
2115
2116		goto queue_status;
2117	default:
2118		pr_err("Unknown transport error for CDB 0x%02x: %d\n",
2119			cmd->t_task_cdb[0], sense_reason);
2120		sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
2121		break;
2122	}
2123
2124	ret = transport_send_check_condition_and_sense(cmd, sense_reason, 0);
2125	if (ret)
2126		goto queue_full;
2127
2128check_stop:
2129	transport_lun_remove_cmd(cmd);
2130	transport_cmd_check_stop_to_fabric(cmd);
2131	return;
2132
2133queue_status:
2134	trace_target_cmd_complete(cmd);
2135	ret = cmd->se_tfo->queue_status(cmd);
2136	if (!ret)
2137		goto check_stop;
2138queue_full:
2139	transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2140}
2141EXPORT_SYMBOL(transport_generic_request_failure);
2142
2143void __target_execute_cmd(struct se_cmd *cmd, bool do_checks)
2144{
2145	sense_reason_t ret;
2146
2147	if (!cmd->execute_cmd) {
2148		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2149		goto err;
2150	}
2151	if (do_checks) {
2152		/*
2153		 * Check for an existing UNIT ATTENTION condition after
2154		 * target_handle_task_attr() has done SAM task attr
2155		 * checking, and possibly have already defered execution
2156		 * out to target_restart_delayed_cmds() context.
2157		 */
2158		ret = target_scsi3_ua_check(cmd);
2159		if (ret)
2160			goto err;
2161
2162		ret = target_alua_state_check(cmd);
2163		if (ret)
2164			goto err;
2165
2166		ret = target_check_reservation(cmd);
2167		if (ret) {
2168			cmd->scsi_status = SAM_STAT_RESERVATION_CONFLICT;
2169			goto err;
2170		}
2171	}
2172
2173	ret = cmd->execute_cmd(cmd);
2174	if (!ret)
2175		return;
2176err:
2177	spin_lock_irq(&cmd->t_state_lock);
2178	cmd->transport_state &= ~CMD_T_SENT;
2179	spin_unlock_irq(&cmd->t_state_lock);
2180
2181	transport_generic_request_failure(cmd, ret);
2182}
2183
2184static int target_write_prot_action(struct se_cmd *cmd)
2185{
2186	u32 sectors;
2187	/*
2188	 * Perform WRITE_INSERT of PI using software emulation when backend
2189	 * device has PI enabled, if the transport has not already generated
2190	 * PI using hardware WRITE_INSERT offload.
2191	 */
2192	switch (cmd->prot_op) {
2193	case TARGET_PROT_DOUT_INSERT:
2194		if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_INSERT))
2195			sbc_dif_generate(cmd);
2196		break;
2197	case TARGET_PROT_DOUT_STRIP:
2198		if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DOUT_STRIP)
2199			break;
2200
2201		sectors = cmd->data_length >> ilog2(cmd->se_dev->dev_attrib.block_size);
2202		cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2203					     sectors, 0, cmd->t_prot_sg, 0);
2204		if (unlikely(cmd->pi_err)) {
2205			spin_lock_irq(&cmd->t_state_lock);
2206			cmd->transport_state &= ~CMD_T_SENT;
2207			spin_unlock_irq(&cmd->t_state_lock);
2208			transport_generic_request_failure(cmd, cmd->pi_err);
2209			return -1;
2210		}
2211		break;
2212	default:
2213		break;
2214	}
2215
2216	return 0;
2217}
2218
2219static bool target_handle_task_attr(struct se_cmd *cmd)
2220{
2221	struct se_device *dev = cmd->se_dev;
2222	unsigned long flags;
2223
2224	if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2225		return false;
2226
2227	cmd->se_cmd_flags |= SCF_TASK_ATTR_SET;
2228
2229	/*
2230	 * Check for the existence of HEAD_OF_QUEUE, and if true return 1
2231	 * to allow the passed struct se_cmd list of tasks to the front of the list.
2232	 */
2233	switch (cmd->sam_task_attr) {
2234	case TCM_HEAD_TAG:
2235		pr_debug("Added HEAD_OF_QUEUE for CDB: 0x%02x\n",
2236			 cmd->t_task_cdb[0]);
2237		return false;
2238	case TCM_ORDERED_TAG:
2239		pr_debug("Added ORDERED for CDB: 0x%02x to ordered list\n",
2240			 cmd->t_task_cdb[0]);
2241		break;
2242	default:
2243		/*
2244		 * For SIMPLE and UNTAGGED Task Attribute commands
2245		 */
2246retry:
2247		if (percpu_ref_tryget_live(&dev->non_ordered))
2248			return false;
2249
2250		break;
2251	}
2252
2253	spin_lock_irqsave(&dev->delayed_cmd_lock, flags);
2254	if (cmd->sam_task_attr == TCM_SIMPLE_TAG &&
2255	    !percpu_ref_is_dying(&dev->non_ordered)) {
2256		spin_unlock_irqrestore(&dev->delayed_cmd_lock, flags);
2257		/* We raced with the last ordered completion so retry. */
2258		goto retry;
2259	} else if (!percpu_ref_is_dying(&dev->non_ordered)) {
2260		percpu_ref_kill(&dev->non_ordered);
2261	}
2262
2263	spin_lock(&cmd->t_state_lock);
2264	cmd->transport_state &= ~CMD_T_SENT;
2265	spin_unlock(&cmd->t_state_lock);
2266
2267	list_add_tail(&cmd->se_delayed_node, &dev->delayed_cmd_list);
2268	spin_unlock_irqrestore(&dev->delayed_cmd_lock, flags);
2269
2270	pr_debug("Added CDB: 0x%02x Task Attr: 0x%02x to delayed CMD listn",
2271		cmd->t_task_cdb[0], cmd->sam_task_attr);
2272	/*
2273	 * We may have no non ordered cmds when this function started or we
2274	 * could have raced with the last simple/head cmd completing, so kick
2275	 * the delayed handler here.
2276	 */
2277	schedule_work(&dev->delayed_cmd_work);
2278	return true;
2279}
2280
2281void target_execute_cmd(struct se_cmd *cmd)
2282{
2283	/*
2284	 * Determine if frontend context caller is requesting the stopping of
2285	 * this command for frontend exceptions.
2286	 *
2287	 * If the received CDB has already been aborted stop processing it here.
2288	 */
2289	if (target_cmd_interrupted(cmd))
2290		return;
2291
2292	spin_lock_irq(&cmd->t_state_lock);
2293	cmd->t_state = TRANSPORT_PROCESSING;
2294	cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
2295	spin_unlock_irq(&cmd->t_state_lock);
2296
2297	if (target_write_prot_action(cmd))
2298		return;
2299
2300	if (target_handle_task_attr(cmd))
2301		return;
2302
2303	__target_execute_cmd(cmd, true);
2304}
2305EXPORT_SYMBOL(target_execute_cmd);
2306
2307/*
2308 * Process all commands up to the last received ORDERED task attribute which
2309 * requires another blocking boundary
2310 */
2311void target_do_delayed_work(struct work_struct *work)
2312{
2313	struct se_device *dev = container_of(work, struct se_device,
2314					     delayed_cmd_work);
2315
2316	spin_lock(&dev->delayed_cmd_lock);
2317	while (!dev->ordered_sync_in_progress) {
2318		struct se_cmd *cmd;
2319
2320		/*
2321		 * We can be woken up early/late due to races or the
2322		 * extra wake up we do when adding commands to the list.
2323		 * We check for both cases here.
2324		 */
2325		if (list_empty(&dev->delayed_cmd_list) ||
2326		    !percpu_ref_is_zero(&dev->non_ordered))
2327			break;
2328
2329		cmd = list_entry(dev->delayed_cmd_list.next,
2330				 struct se_cmd, se_delayed_node);
2331		cmd->se_cmd_flags |= SCF_TASK_ORDERED_SYNC;
2332		cmd->transport_state |= CMD_T_SENT;
2333
2334		dev->ordered_sync_in_progress = true;
2335
2336		list_del(&cmd->se_delayed_node);
2337		spin_unlock(&dev->delayed_cmd_lock);
2338
2339		__target_execute_cmd(cmd, true);
2340		spin_lock(&dev->delayed_cmd_lock);
2341	}
2342	spin_unlock(&dev->delayed_cmd_lock);
2343}
2344
2345static void transport_complete_ordered_sync(struct se_cmd *cmd)
2346{
2347	struct se_device *dev = cmd->se_dev;
2348	unsigned long flags;
2349
2350	spin_lock_irqsave(&dev->delayed_cmd_lock, flags);
2351	dev->dev_cur_ordered_id++;
2352
2353	pr_debug("Incremented dev_cur_ordered_id: %u for type %d\n",
2354		 dev->dev_cur_ordered_id, cmd->sam_task_attr);
2355
2356	dev->ordered_sync_in_progress = false;
2357
2358	if (list_empty(&dev->delayed_cmd_list))
2359		percpu_ref_resurrect(&dev->non_ordered);
2360	else
2361		schedule_work(&dev->delayed_cmd_work);
2362
2363	spin_unlock_irqrestore(&dev->delayed_cmd_lock, flags);
2364}
2365
2366/*
2367 * Called from I/O completion to determine which dormant/delayed
2368 * and ordered cmds need to have their tasks added to the execution queue.
2369 */
2370static void transport_complete_task_attr(struct se_cmd *cmd)
2371{
2372	struct se_device *dev = cmd->se_dev;
2373
2374	if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
2375		return;
2376
2377	if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET))
2378		return;
2379
2380	cmd->se_cmd_flags &= ~SCF_TASK_ATTR_SET;
2381
2382	if (cmd->se_cmd_flags & SCF_TASK_ORDERED_SYNC) {
2383		transport_complete_ordered_sync(cmd);
2384		return;
2385	}
2386
2387	switch (cmd->sam_task_attr) {
2388	case TCM_SIMPLE_TAG:
2389		percpu_ref_put(&dev->non_ordered);
2390		break;
2391	case TCM_ORDERED_TAG:
2392		/* All ordered should have been executed as sync */
2393		WARN_ON(1);
2394		break;
2395	}
2396}
2397
2398static void transport_complete_qf(struct se_cmd *cmd)
2399{
2400	int ret = 0;
2401
2402	transport_complete_task_attr(cmd);
2403	/*
2404	 * If a fabric driver ->write_pending() or ->queue_data_in() callback
2405	 * has returned neither -ENOMEM or -EAGAIN, assume it's fatal and
2406	 * the same callbacks should not be retried.  Return CHECK_CONDITION
2407	 * if a scsi_status is not already set.
2408	 *
2409	 * If a fabric driver ->queue_status() has returned non zero, always
2410	 * keep retrying no matter what..
2411	 */
2412	if (cmd->t_state == TRANSPORT_COMPLETE_QF_ERR) {
2413		if (cmd->scsi_status)
2414			goto queue_status;
2415
2416		translate_sense_reason(cmd, TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE);
2417		goto queue_status;
2418	}
2419
2420	/*
2421	 * Check if we need to send a sense buffer from
2422	 * the struct se_cmd in question. We do NOT want
2423	 * to take this path of the IO has been marked as
2424	 * needing to be treated like a "normal read". This
2425	 * is the case if it's a tape read, and either the
2426	 * FM, EOM, or ILI bits are set, but there is no
2427	 * sense data.
2428	 */
2429	if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2430	    cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE)
2431		goto queue_status;
2432
2433	switch (cmd->data_direction) {
2434	case DMA_FROM_DEVICE:
2435		/* queue status if not treating this as a normal read */
2436		if (cmd->scsi_status &&
2437		    !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2438			goto queue_status;
2439
2440		trace_target_cmd_complete(cmd);
2441		ret = cmd->se_tfo->queue_data_in(cmd);
2442		break;
2443	case DMA_TO_DEVICE:
2444		if (cmd->se_cmd_flags & SCF_BIDI) {
2445			ret = cmd->se_tfo->queue_data_in(cmd);
2446			break;
2447		}
2448		fallthrough;
2449	case DMA_NONE:
2450queue_status:
2451		trace_target_cmd_complete(cmd);
2452		ret = cmd->se_tfo->queue_status(cmd);
2453		break;
2454	default:
2455		break;
2456	}
2457
2458	if (ret < 0) {
2459		transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2460		return;
2461	}
2462	transport_lun_remove_cmd(cmd);
2463	transport_cmd_check_stop_to_fabric(cmd);
2464}
2465
2466static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev,
2467					int err, bool write_pending)
2468{
2469	/*
2470	 * -EAGAIN or -ENOMEM signals retry of ->write_pending() and/or
2471	 * ->queue_data_in() callbacks from new process context.
2472	 *
2473	 * Otherwise for other errors, transport_complete_qf() will send
2474	 * CHECK_CONDITION via ->queue_status() instead of attempting to
2475	 * retry associated fabric driver data-transfer callbacks.
2476	 */
2477	if (err == -EAGAIN || err == -ENOMEM) {
2478		cmd->t_state = (write_pending) ? TRANSPORT_COMPLETE_QF_WP :
2479						 TRANSPORT_COMPLETE_QF_OK;
2480	} else {
2481		pr_warn_ratelimited("Got unknown fabric queue status: %d\n", err);
2482		cmd->t_state = TRANSPORT_COMPLETE_QF_ERR;
2483	}
2484
2485	spin_lock_irq(&dev->qf_cmd_lock);
2486	list_add_tail(&cmd->se_qf_node, &cmd->se_dev->qf_cmd_list);
2487	atomic_inc_mb(&dev->dev_qf_count);
2488	spin_unlock_irq(&cmd->se_dev->qf_cmd_lock);
2489
2490	schedule_work(&cmd->se_dev->qf_work_queue);
2491}
2492
2493static bool target_read_prot_action(struct se_cmd *cmd)
2494{
2495	switch (cmd->prot_op) {
2496	case TARGET_PROT_DIN_STRIP:
2497		if (!(cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_STRIP)) {
2498			u32 sectors = cmd->data_length >>
2499				  ilog2(cmd->se_dev->dev_attrib.block_size);
2500
2501			cmd->pi_err = sbc_dif_verify(cmd, cmd->t_task_lba,
2502						     sectors, 0, cmd->t_prot_sg,
2503						     0);
2504			if (cmd->pi_err)
2505				return true;
2506		}
2507		break;
2508	case TARGET_PROT_DIN_INSERT:
2509		if (cmd->se_sess->sup_prot_ops & TARGET_PROT_DIN_INSERT)
2510			break;
2511
2512		sbc_dif_generate(cmd);
2513		break;
2514	default:
2515		break;
2516	}
2517
2518	return false;
2519}
2520
2521static void target_complete_ok_work(struct work_struct *work)
2522{
2523	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
2524	int ret;
2525
2526	/*
2527	 * Check if we need to move delayed/dormant tasks from cmds on the
2528	 * delayed execution list after a HEAD_OF_QUEUE or ORDERED Task
2529	 * Attribute.
2530	 */
2531	transport_complete_task_attr(cmd);
2532
2533	/*
2534	 * Check to schedule QUEUE_FULL work, or execute an existing
2535	 * cmd->transport_qf_callback()
2536	 */
2537	if (atomic_read(&cmd->se_dev->dev_qf_count) != 0)
2538		schedule_work(&cmd->se_dev->qf_work_queue);
2539
2540	/*
2541	 * Check if we need to send a sense buffer from
2542	 * the struct se_cmd in question. We do NOT want
2543	 * to take this path of the IO has been marked as
2544	 * needing to be treated like a "normal read". This
2545	 * is the case if it's a tape read, and either the
2546	 * FM, EOM, or ILI bits are set, but there is no
2547	 * sense data.
2548	 */
2549	if (!(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL) &&
2550	    cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) {
2551		WARN_ON(!cmd->scsi_status);
2552		ret = transport_send_check_condition_and_sense(
2553					cmd, 0, 1);
2554		if (ret)
2555			goto queue_full;
2556
2557		transport_lun_remove_cmd(cmd);
2558		transport_cmd_check_stop_to_fabric(cmd);
2559		return;
2560	}
2561	/*
2562	 * Check for a callback, used by amongst other things
2563	 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
2564	 */
2565	if (cmd->transport_complete_callback) {
2566		sense_reason_t rc;
2567		bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE);
2568		bool zero_dl = !(cmd->data_length);
2569		int post_ret = 0;
2570
2571		rc = cmd->transport_complete_callback(cmd, true, &post_ret);
2572		if (!rc && !post_ret) {
2573			if (caw && zero_dl)
2574				goto queue_rsp;
2575
2576			return;
2577		} else if (rc) {
2578			ret = transport_send_check_condition_and_sense(cmd,
2579						rc, 0);
2580			if (ret)
2581				goto queue_full;
2582
2583			transport_lun_remove_cmd(cmd);
2584			transport_cmd_check_stop_to_fabric(cmd);
2585			return;
2586		}
2587	}
2588
2589queue_rsp:
2590	switch (cmd->data_direction) {
2591	case DMA_FROM_DEVICE:
2592		/*
2593		 * if this is a READ-type IO, but SCSI status
2594		 * is set, then skip returning data and just
2595		 * return the status -- unless this IO is marked
2596		 * as needing to be treated as a normal read,
2597		 * in which case we want to go ahead and return
2598		 * the data. This happens, for example, for tape
2599		 * reads with the FM, EOM, or ILI bits set, with
2600		 * no sense data.
2601		 */
2602		if (cmd->scsi_status &&
2603		    !(cmd->se_cmd_flags & SCF_TREAT_READ_AS_NORMAL))
2604			goto queue_status;
2605
2606		if (cmd->se_lun->lun_stats)
2607			this_cpu_add(cmd->se_lun->lun_stats->tx_data_octets,
2608				     cmd->data_length);
2609		/*
2610		 * Perform READ_STRIP of PI using software emulation when
2611		 * backend had PI enabled, if the transport will not be
2612		 * performing hardware READ_STRIP offload.
2613		 */
2614		if (target_read_prot_action(cmd)) {
2615			ret = transport_send_check_condition_and_sense(cmd,
2616						cmd->pi_err, 0);
2617			if (ret)
2618				goto queue_full;
2619
2620			transport_lun_remove_cmd(cmd);
2621			transport_cmd_check_stop_to_fabric(cmd);
2622			return;
2623		}
2624
2625		trace_target_cmd_complete(cmd);
2626		ret = cmd->se_tfo->queue_data_in(cmd);
2627		if (ret)
2628			goto queue_full;
2629		break;
2630	case DMA_TO_DEVICE:
2631		if (cmd->se_lun->lun_stats)
2632			this_cpu_add(cmd->se_lun->lun_stats->rx_data_octets,
2633				     cmd->data_length);
2634		/*
2635		 * Check if we need to send READ payload for BIDI-COMMAND
2636		 */
2637		if (cmd->se_cmd_flags & SCF_BIDI) {
2638			if (cmd->se_lun->lun_stats)
2639				this_cpu_add(cmd->se_lun->lun_stats->tx_data_octets,
2640					     cmd->data_length);
2641			ret = cmd->se_tfo->queue_data_in(cmd);
2642			if (ret)
2643				goto queue_full;
2644			break;
2645		}
2646		fallthrough;
2647	case DMA_NONE:
2648queue_status:
2649		trace_target_cmd_complete(cmd);
2650		ret = cmd->se_tfo->queue_status(cmd);
2651		if (ret)
2652			goto queue_full;
2653		break;
2654	default:
2655		break;
2656	}
2657
2658	transport_lun_remove_cmd(cmd);
2659	transport_cmd_check_stop_to_fabric(cmd);
2660	return;
2661
2662queue_full:
2663	pr_debug("Handling complete_ok QUEUE_FULL: se_cmd: %p,"
2664		" data_direction: %d\n", cmd, cmd->data_direction);
2665
2666	transport_handle_queue_full(cmd, cmd->se_dev, ret, false);
2667}
2668
2669void target_free_sgl(struct scatterlist *sgl, int nents)
2670{
2671	sgl_free_n_order(sgl, nents, 0);
2672}
2673EXPORT_SYMBOL(target_free_sgl);
2674
2675static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
2676{
2677	/*
2678	 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
2679	 * emulation, and free + reset pointers if necessary..
2680	 */
2681	if (!cmd->t_data_sg_orig)
2682		return;
2683
2684	kfree(cmd->t_data_sg);
2685	cmd->t_data_sg = cmd->t_data_sg_orig;
2686	cmd->t_data_sg_orig = NULL;
2687	cmd->t_data_nents = cmd->t_data_nents_orig;
2688	cmd->t_data_nents_orig = 0;
2689}
2690
2691static inline void transport_free_pages(struct se_cmd *cmd)
2692{
2693	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2694		target_free_sgl(cmd->t_prot_sg, cmd->t_prot_nents);
2695		cmd->t_prot_sg = NULL;
2696		cmd->t_prot_nents = 0;
2697	}
2698
2699	if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
2700		/*
2701		 * Release special case READ buffer payload required for
2702		 * SG_TO_MEM_NOALLOC to function with COMPARE_AND_WRITE
2703		 */
2704		if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) {
2705			target_free_sgl(cmd->t_bidi_data_sg,
2706					   cmd->t_bidi_data_nents);
2707			cmd->t_bidi_data_sg = NULL;
2708			cmd->t_bidi_data_nents = 0;
2709		}
2710		transport_reset_sgl_orig(cmd);
2711		return;
2712	}
2713	transport_reset_sgl_orig(cmd);
2714
2715	target_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
2716	cmd->t_data_sg = NULL;
2717	cmd->t_data_nents = 0;
2718
2719	target_free_sgl(cmd->t_bidi_data_sg, cmd->t_bidi_data_nents);
2720	cmd->t_bidi_data_sg = NULL;
2721	cmd->t_bidi_data_nents = 0;
2722}
2723
2724void *transport_kmap_data_sg(struct se_cmd *cmd)
2725{
2726	struct scatterlist *sg = cmd->t_data_sg;
2727	struct page **pages;
2728	int i;
2729
2730	/*
2731	 * We need to take into account a possible offset here for fabrics like
2732	 * tcm_loop who may be using a contig buffer from the SCSI midlayer for
2733	 * control CDBs passed as SGLs via transport_generic_map_mem_to_cmd()
2734	 */
2735	if (!cmd->t_data_nents)
2736		return NULL;
2737
2738	BUG_ON(!sg);
2739	if (cmd->t_data_nents == 1)
2740		return kmap(sg_page(sg)) + sg->offset;
2741
2742	/* >1 page. use vmap */
2743	pages = kmalloc_array(cmd->t_data_nents, sizeof(*pages), GFP_KERNEL);
2744	if (!pages)
2745		return NULL;
2746
2747	/* convert sg[] to pages[] */
2748	for_each_sg(cmd->t_data_sg, sg, cmd->t_data_nents, i) {
2749		pages[i] = sg_page(sg);
2750	}
2751
2752	cmd->t_data_vmap = vmap(pages, cmd->t_data_nents,  VM_MAP, PAGE_KERNEL);
2753	kfree(pages);
2754	if (!cmd->t_data_vmap)
2755		return NULL;
2756
2757	return cmd->t_data_vmap + cmd->t_data_sg[0].offset;
2758}
2759EXPORT_SYMBOL(transport_kmap_data_sg);
2760
2761void transport_kunmap_data_sg(struct se_cmd *cmd)
2762{
2763	if (!cmd->t_data_nents) {
2764		return;
2765	} else if (cmd->t_data_nents == 1) {
2766		kunmap(sg_page(cmd->t_data_sg));
2767		return;
2768	}
2769
2770	vunmap(cmd->t_data_vmap);
2771	cmd->t_data_vmap = NULL;
2772}
2773EXPORT_SYMBOL(transport_kunmap_data_sg);
2774
2775int
2776target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
2777		 bool zero_page, bool chainable)
2778{
2779	gfp_t gfp = GFP_KERNEL | (zero_page ? __GFP_ZERO : 0);
2780
2781	*sgl = sgl_alloc_order(length, 0, chainable, gfp, nents);
2782	return *sgl ? 0 : -ENOMEM;
2783}
2784EXPORT_SYMBOL(target_alloc_sgl);
2785
2786/*
2787 * Allocate any required resources to execute the command.  For writes we
2788 * might not have the payload yet, so notify the fabric via a call to
2789 * ->write_pending instead. Otherwise place it on the execution queue.
2790 */
2791sense_reason_t
2792transport_generic_new_cmd(struct se_cmd *cmd)
2793{
2794	unsigned long flags;
2795	int ret = 0;
2796	bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
2797
2798	if (cmd->prot_op != TARGET_PROT_NORMAL &&
2799	    !(cmd->se_cmd_flags & SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC)) {
2800		ret = target_alloc_sgl(&cmd->t_prot_sg, &cmd->t_prot_nents,
2801				       cmd->prot_length, true, false);
2802		if (ret < 0)
2803			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2804	}
2805
2806	/*
2807	 * Determine if the TCM fabric module has already allocated physical
2808	 * memory, and is directly calling transport_generic_map_mem_to_cmd()
2809	 * beforehand.
2810	 */
2811	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
2812	    cmd->data_length) {
2813
2814		if ((cmd->se_cmd_flags & SCF_BIDI) ||
2815		    (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
2816			u32 bidi_length;
2817
2818			if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
2819				bidi_length = cmd->t_task_nolb *
2820					      cmd->se_dev->dev_attrib.block_size;
2821			else
2822				bidi_length = cmd->data_length;
2823
2824			ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2825					       &cmd->t_bidi_data_nents,
2826					       bidi_length, zero_flag, false);
2827			if (ret < 0)
2828				return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2829		}
2830
2831		ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
2832				       cmd->data_length, zero_flag, false);
2833		if (ret < 0)
2834			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2835	} else if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
2836		    cmd->data_length) {
2837		/*
2838		 * Special case for COMPARE_AND_WRITE with fabrics
2839		 * using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC.
2840		 */
2841		u32 caw_length = cmd->t_task_nolb *
2842				 cmd->se_dev->dev_attrib.block_size;
2843
2844		ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
2845				       &cmd->t_bidi_data_nents,
2846				       caw_length, zero_flag, false);
2847		if (ret < 0)
2848			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2849	}
2850	/*
2851	 * If this command is not a write we can execute it right here,
2852	 * for write buffers we need to notify the fabric driver first
2853	 * and let it call back once the write buffers are ready.
2854	 */
2855	target_add_to_state_list(cmd);
2856	if (cmd->data_direction != DMA_TO_DEVICE || cmd->data_length == 0) {
2857		target_execute_cmd(cmd);
2858		return 0;
2859	}
2860
2861	spin_lock_irqsave(&cmd->t_state_lock, flags);
2862	cmd->t_state = TRANSPORT_WRITE_PENDING;
2863	/*
2864	 * Determine if frontend context caller is requesting the stopping of
2865	 * this command for frontend exceptions.
2866	 */
2867	if (cmd->transport_state & CMD_T_STOP &&
2868	    !cmd->se_tfo->write_pending_must_be_called) {
2869		pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08llx\n",
2870			 __func__, __LINE__, cmd->tag);
2871
2872		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2873
2874		complete_all(&cmd->t_transport_stop_comp);
2875		return 0;
2876	}
2877	cmd->transport_state &= ~CMD_T_ACTIVE;
2878	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2879
2880	ret = cmd->se_tfo->write_pending(cmd);
2881	if (ret)
2882		goto queue_full;
2883
2884	return 0;
2885
2886queue_full:
2887	pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n", cmd);
2888	transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2889	return 0;
2890}
2891EXPORT_SYMBOL(transport_generic_new_cmd);
2892
2893static void transport_write_pending_qf(struct se_cmd *cmd)
2894{
2895	unsigned long flags;
2896	int ret;
2897	bool stop;
2898
2899	spin_lock_irqsave(&cmd->t_state_lock, flags);
2900	stop = (cmd->transport_state & (CMD_T_STOP | CMD_T_ABORTED));
2901	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2902
2903	if (stop) {
2904		pr_debug("%s:%d CMD_T_STOP|CMD_T_ABORTED for ITT: 0x%08llx\n",
2905			__func__, __LINE__, cmd->tag);
2906		complete_all(&cmd->t_transport_stop_comp);
2907		return;
2908	}
2909
2910	ret = cmd->se_tfo->write_pending(cmd);
2911	if (ret) {
2912		pr_debug("Handling write_pending QUEUE__FULL: se_cmd: %p\n",
2913			 cmd);
2914		transport_handle_queue_full(cmd, cmd->se_dev, ret, true);
2915	}
2916}
2917
2918static bool
2919__transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *,
2920			   unsigned long *flags);
2921
2922static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas)
2923{
2924	unsigned long flags;
2925
2926	spin_lock_irqsave(&cmd->t_state_lock, flags);
2927	__transport_wait_for_tasks(cmd, true, aborted, tas, &flags);
2928	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
2929}
2930
2931/*
2932 * Call target_put_sess_cmd() and wait until target_release_cmd_kref(@cmd) has
2933 * finished.
2934 */
2935void target_put_cmd_and_wait(struct se_cmd *cmd)
2936{
2937	DECLARE_COMPLETION_ONSTACK(compl);
2938
2939	WARN_ON_ONCE(cmd->abrt_compl);
2940	cmd->abrt_compl = &compl;
2941	target_put_sess_cmd(cmd);
2942	wait_for_completion(&compl);
2943}
2944
2945/*
2946 * This function is called by frontend drivers after processing of a command
2947 * has finished.
2948 *
2949 * The protocol for ensuring that either the regular frontend command
2950 * processing flow or target_handle_abort() code drops one reference is as
2951 * follows:
2952 * - Calling .queue_data_in(), .queue_status() or queue_tm_rsp() will cause
2953 *   the frontend driver to call this function synchronously or asynchronously.
2954 *   That will cause one reference to be dropped.
2955 * - During regular command processing the target core sets CMD_T_COMPLETE
2956 *   before invoking one of the .queue_*() functions.
2957 * - The code that aborts commands skips commands and TMFs for which
2958 *   CMD_T_COMPLETE has been set.
2959 * - CMD_T_ABORTED is set atomically after the CMD_T_COMPLETE check for
2960 *   commands that will be aborted.
2961 * - If the CMD_T_ABORTED flag is set but CMD_T_TAS has not been set
2962 *   transport_generic_free_cmd() skips its call to target_put_sess_cmd().
2963 * - For aborted commands for which CMD_T_TAS has been set .queue_status() will
2964 *   be called and will drop a reference.
2965 * - For aborted commands for which CMD_T_TAS has not been set .aborted_task()
2966 *   will be called. target_handle_abort() will drop the final reference.
2967 */
2968int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
2969{
2970	DECLARE_COMPLETION_ONSTACK(compl);
2971	int ret = 0;
2972	bool aborted = false, tas = false;
2973
2974	if (wait_for_tasks)
2975		target_wait_free_cmd(cmd, &aborted, &tas);
2976
2977	if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) {
2978		/*
2979		 * Handle WRITE failure case where transport_generic_new_cmd()
2980		 * has already added se_cmd to state_list, but fabric has
2981		 * failed command before I/O submission.
2982		 */
2983		if (cmd->state_active)
2984			target_remove_from_state_list(cmd);
2985
2986		if (cmd->se_lun)
2987			transport_lun_remove_cmd(cmd);
2988	}
2989	if (aborted)
2990		cmd->free_compl = &compl;
2991	ret = target_put_sess_cmd(cmd);
2992	if (aborted) {
2993		pr_debug("Detected CMD_T_ABORTED for ITT: %llu\n", cmd->tag);
2994		wait_for_completion(&compl);
2995		ret = 1;
2996	}
2997	return ret;
2998}
2999EXPORT_SYMBOL(transport_generic_free_cmd);
3000
3001/**
3002 * target_get_sess_cmd - Verify the session is accepting cmds and take ref
3003 * @se_cmd:	command descriptor to add
3004 * @ack_kref:	Signal that fabric will perform an ack target_put_sess_cmd()
3005 */
3006int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref)
3007{
3008	int ret = 0;
3009
3010	/*
3011	 * Add a second kref if the fabric caller is expecting to handle
3012	 * fabric acknowledgement that requires two target_put_sess_cmd()
3013	 * invocations before se_cmd descriptor release.
3014	 */
3015	if (ack_kref) {
3016		kref_get(&se_cmd->cmd_kref);
3017		se_cmd->se_cmd_flags |= SCF_ACK_KREF;
3018	}
3019
3020	/*
3021	 * Users like xcopy do not use counters since they never do a stop
3022	 * and wait.
3023	 */
3024	if (se_cmd->cmd_cnt) {
3025		if (!percpu_ref_tryget_live(&se_cmd->cmd_cnt->refcnt))
3026			ret = -ESHUTDOWN;
3027	}
3028	if (ret && ack_kref)
3029		target_put_sess_cmd(se_cmd);
3030
3031	return ret;
3032}
3033EXPORT_SYMBOL(target_get_sess_cmd);
3034
3035static void target_free_cmd_mem(struct se_cmd *cmd)
3036{
3037	transport_free_pages(cmd);
3038
3039	if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
3040		core_tmr_release_req(cmd->se_tmr_req);
3041	if (cmd->t_task_cdb != cmd->__t_task_cdb)
3042		kfree(cmd->t_task_cdb);
3043}
3044
3045static void target_release_cmd_kref(struct kref *kref)
3046{
3047	struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref);
3048	struct target_cmd_counter *cmd_cnt = se_cmd->cmd_cnt;
3049	struct completion *free_compl = se_cmd->free_compl;
3050	struct completion *abrt_compl = se_cmd->abrt_compl;
3051
3052	target_free_cmd_mem(se_cmd);
3053	se_cmd->se_tfo->release_cmd(se_cmd);
3054	if (free_compl)
3055		complete(free_compl);
3056	if (abrt_compl)
3057		complete(abrt_compl);
3058
3059	if (cmd_cnt)
3060		percpu_ref_put(&cmd_cnt->refcnt);
3061}
3062
3063/**
3064 * target_put_sess_cmd - decrease the command reference count
3065 * @se_cmd:	command to drop a reference from
3066 *
3067 * Returns 1 if and only if this target_put_sess_cmd() call caused the
3068 * refcount to drop to zero. Returns zero otherwise.
3069 */
3070int target_put_sess_cmd(struct se_cmd *se_cmd)
3071{
3072	return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref);
3073}
3074EXPORT_SYMBOL(target_put_sess_cmd);
3075
3076static const char *data_dir_name(enum dma_data_direction d)
3077{
3078	switch (d) {
3079	case DMA_BIDIRECTIONAL:	return "BIDI";
3080	case DMA_TO_DEVICE:	return "WRITE";
3081	case DMA_FROM_DEVICE:	return "READ";
3082	case DMA_NONE:		return "NONE";
3083	}
3084
3085	return "(?)";
3086}
3087
3088static const char *cmd_state_name(enum transport_state_table t)
3089{
3090	switch (t) {
3091	case TRANSPORT_NO_STATE:	return "NO_STATE";
3092	case TRANSPORT_NEW_CMD:		return "NEW_CMD";
3093	case TRANSPORT_WRITE_PENDING:	return "WRITE_PENDING";
3094	case TRANSPORT_PROCESSING:	return "PROCESSING";
3095	case TRANSPORT_COMPLETE:	return "COMPLETE";
3096	case TRANSPORT_ISTATE_PROCESSING:
3097					return "ISTATE_PROCESSING";
3098	case TRANSPORT_COMPLETE_QF_WP:	return "COMPLETE_QF_WP";
3099	case TRANSPORT_COMPLETE_QF_OK:	return "COMPLETE_QF_OK";
3100	case TRANSPORT_COMPLETE_QF_ERR:	return "COMPLETE_QF_ERR";
3101	}
3102
3103	return "(?)";
3104}
3105
3106static void target_append_str(char **str, const char *txt)
3107{
3108	char *prev = *str;
3109
3110	*str = *str ? kasprintf(GFP_ATOMIC, "%s,%s", *str, txt) :
3111		kstrdup(txt, GFP_ATOMIC);
3112	kfree(prev);
3113}
3114
3115/*
3116 * Convert a transport state bitmask into a string. The caller is
3117 * responsible for freeing the returned pointer.
3118 */
3119static char *target_ts_to_str(u32 ts)
3120{
3121	char *str = NULL;
3122
3123	if (ts & CMD_T_ABORTED)
3124		target_append_str(&str, "aborted");
3125	if (ts & CMD_T_ACTIVE)
3126		target_append_str(&str, "active");
3127	if (ts & CMD_T_COMPLETE)
3128		target_append_str(&str, "complete");
3129	if (ts & CMD_T_SENT)
3130		target_append_str(&str, "sent");
3131	if (ts & CMD_T_STOP)
3132		target_append_str(&str, "stop");
3133	if (ts & CMD_T_FABRIC_STOP)
3134		target_append_str(&str, "fabric_stop");
3135
3136	return str;
3137}
3138
3139static const char *target_tmf_name(enum tcm_tmreq_table tmf)
3140{
3141	switch (tmf) {
3142	case TMR_ABORT_TASK:		return "ABORT_TASK";
3143	case TMR_ABORT_TASK_SET:	return "ABORT_TASK_SET";
3144	case TMR_CLEAR_ACA:		return "CLEAR_ACA";
3145	case TMR_CLEAR_TASK_SET:	return "CLEAR_TASK_SET";
3146	case TMR_LUN_RESET:		return "LUN_RESET";
3147	case TMR_TARGET_WARM_RESET:	return "TARGET_WARM_RESET";
3148	case TMR_TARGET_COLD_RESET:	return "TARGET_COLD_RESET";
3149	case TMR_LUN_RESET_PRO:		return "LUN_RESET_PRO";
3150	case TMR_UNKNOWN:		break;
3151	}
3152	return "(?)";
3153}
3154
3155void target_show_cmd(const char *pfx, struct se_cmd *cmd)
3156{
3157	char *ts_str = target_ts_to_str(cmd->transport_state);
3158	const u8 *cdb = cmd->t_task_cdb;
3159	struct se_tmr_req *tmf = cmd->se_tmr_req;
3160
3161	if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
3162		pr_debug("%scmd %#02x:%#02x with tag %#llx dir %s i_state %d t_state %s len %d refcnt %d transport_state %s\n",
3163			 pfx, cdb[0], cdb[1], cmd->tag,
3164			 data_dir_name(cmd->data_direction),
3165			 cmd->se_tfo->get_cmd_state(cmd),
3166			 cmd_state_name(cmd->t_state), cmd->data_length,
3167			 kref_read(&cmd->cmd_kref), ts_str);
3168	} else {
3169		pr_debug("%stmf %s with tag %#llx ref_task_tag %#llx i_state %d t_state %s refcnt %d transport_state %s\n",
3170			 pfx, target_tmf_name(tmf->function), cmd->tag,
3171			 tmf->ref_task_tag, cmd->se_tfo->get_cmd_state(cmd),
3172			 cmd_state_name(cmd->t_state),
3173			 kref_read(&cmd->cmd_kref), ts_str);
3174	}
3175	kfree(ts_str);
3176}
3177EXPORT_SYMBOL(target_show_cmd);
3178
3179static void target_stop_cmd_counter_confirm(struct percpu_ref *ref)
3180{
3181	struct target_cmd_counter *cmd_cnt = container_of(ref,
3182						struct target_cmd_counter,
3183						refcnt);
3184	complete_all(&cmd_cnt->stop_done);
3185}
3186
3187/**
3188 * target_stop_cmd_counter - Stop new IO from being added to the counter.
3189 * @cmd_cnt: counter to stop
3190 */
3191void target_stop_cmd_counter(struct target_cmd_counter *cmd_cnt)
3192{
3193	pr_debug("Stopping command counter.\n");
3194	if (!atomic_cmpxchg(&cmd_cnt->stopped, 0, 1))
3195		percpu_ref_kill_and_confirm(&cmd_cnt->refcnt,
3196					    target_stop_cmd_counter_confirm);
3197}
3198EXPORT_SYMBOL_GPL(target_stop_cmd_counter);
3199
3200/**
3201 * target_stop_session - Stop new IO from being queued on the session.
3202 * @se_sess: session to stop
3203 */
3204void target_stop_session(struct se_session *se_sess)
3205{
3206	target_stop_cmd_counter(se_sess->cmd_cnt);
3207}
3208EXPORT_SYMBOL(target_stop_session);
3209
3210/**
3211 * target_wait_for_cmds - Wait for outstanding cmds.
3212 * @cmd_cnt: counter to wait for active I/O for.
3213 */
3214void target_wait_for_cmds(struct target_cmd_counter *cmd_cnt)
3215{
3216	int ret;
3217
3218	WARN_ON_ONCE(!atomic_read(&cmd_cnt->stopped));
3219
3220	do {
3221		pr_debug("Waiting for running cmds to complete.\n");
3222		ret = wait_event_timeout(cmd_cnt->refcnt_wq,
3223					 percpu_ref_is_zero(&cmd_cnt->refcnt),
3224					 180 * HZ);
3225	} while (ret <= 0);
3226
3227	wait_for_completion(&cmd_cnt->stop_done);
3228	pr_debug("Waiting for cmds done.\n");
3229}
3230EXPORT_SYMBOL_GPL(target_wait_for_cmds);
3231
3232/**
3233 * target_wait_for_sess_cmds - Wait for outstanding commands
3234 * @se_sess: session to wait for active I/O
3235 */
3236void target_wait_for_sess_cmds(struct se_session *se_sess)
3237{
3238	target_wait_for_cmds(se_sess->cmd_cnt);
3239}
3240EXPORT_SYMBOL(target_wait_for_sess_cmds);
3241
3242/*
3243 * Prevent that new percpu_ref_tryget_live() calls succeed and wait until
3244 * all references to the LUN have been released. Called during LUN shutdown.
3245 */
3246void transport_clear_lun_ref(struct se_lun *lun)
3247{
3248	percpu_ref_kill(&lun->lun_ref);
3249	wait_for_completion(&lun->lun_shutdown_comp);
3250}
3251
3252static bool
3253__transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop,
3254			   bool *aborted, bool *tas, unsigned long *flags)
3255	__releases(&cmd->t_state_lock)
3256	__acquires(&cmd->t_state_lock)
3257{
3258	lockdep_assert_held(&cmd->t_state_lock);
3259
3260	if (fabric_stop)
3261		cmd->transport_state |= CMD_T_FABRIC_STOP;
3262
3263	if (cmd->transport_state & CMD_T_ABORTED)
3264		*aborted = true;
3265
3266	if (cmd->transport_state & CMD_T_TAS)
3267		*tas = true;
3268
3269	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
3270	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3271		return false;
3272
3273	if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
3274	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
3275		return false;
3276
3277	if (!(cmd->transport_state & CMD_T_ACTIVE))
3278		return false;
3279
3280	if (fabric_stop && *aborted)
3281		return false;
3282
3283	cmd->transport_state |= CMD_T_STOP;
3284
3285	target_show_cmd("wait_for_tasks: Stopping ", cmd);
3286
3287	spin_unlock_irqrestore(&cmd->t_state_lock, *flags);
3288
3289	while (!wait_for_completion_timeout(&cmd->t_transport_stop_comp,
3290					    180 * HZ))
3291		target_show_cmd("wait for tasks: ", cmd);
3292
3293	spin_lock_irqsave(&cmd->t_state_lock, *flags);
3294	cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP);
3295
3296	pr_debug("wait_for_tasks: Stopped wait_for_completion(&cmd->"
3297		 "t_transport_stop_comp) for ITT: 0x%08llx\n", cmd->tag);
3298
3299	return true;
3300}
3301
3302/**
3303 * transport_wait_for_tasks - set CMD_T_STOP and wait for t_transport_stop_comp
3304 * @cmd: command to wait on
3305 */
3306bool transport_wait_for_tasks(struct se_cmd *cmd)
3307{
3308	unsigned long flags;
3309	bool ret, aborted = false, tas = false;
3310
3311	spin_lock_irqsave(&cmd->t_state_lock, flags);
3312	ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags);
3313	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3314
3315	return ret;
3316}
3317EXPORT_SYMBOL(transport_wait_for_tasks);
3318
3319struct sense_detail {
3320	u8 key;
3321	u8 asc;
3322	u8 ascq;
3323	bool add_sense_info;
3324};
3325
3326static const struct sense_detail sense_detail_table[] = {
3327	[TCM_NO_SENSE] = {
3328		.key = NOT_READY
3329	},
3330	[TCM_NON_EXISTENT_LUN] = {
3331		.key = ILLEGAL_REQUEST,
3332		.asc = 0x25 /* LOGICAL UNIT NOT SUPPORTED */
3333	},
3334	[TCM_UNSUPPORTED_SCSI_OPCODE] = {
3335		.key = ILLEGAL_REQUEST,
3336		.asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3337	},
3338	[TCM_SECTOR_COUNT_TOO_MANY] = {
3339		.key = ILLEGAL_REQUEST,
3340		.asc = 0x20, /* INVALID COMMAND OPERATION CODE */
3341	},
3342	[TCM_UNKNOWN_MODE_PAGE] = {
3343		.key = ILLEGAL_REQUEST,
3344		.asc = 0x24, /* INVALID FIELD IN CDB */
3345	},
3346	[TCM_CHECK_CONDITION_ABORT_CMD] = {
3347		.key = ABORTED_COMMAND,
3348		.asc = 0x29, /* BUS DEVICE RESET FUNCTION OCCURRED */
3349		.ascq = 0x03,
3350	},
3351	[TCM_INCORRECT_AMOUNT_OF_DATA] = {
3352		.key = ABORTED_COMMAND,
3353		.asc = 0x0c, /* WRITE ERROR */
3354		.ascq = 0x0d, /* NOT ENOUGH UNSOLICITED DATA */
3355	},
3356	[TCM_INVALID_CDB_FIELD] = {
3357		.key = ILLEGAL_REQUEST,
3358		.asc = 0x24, /* INVALID FIELD IN CDB */
3359	},
3360	[TCM_INVALID_PARAMETER_LIST] = {
3361		.key = ILLEGAL_REQUEST,
3362		.asc = 0x26, /* INVALID FIELD IN PARAMETER LIST */
3363	},
3364	[TCM_TOO_MANY_TARGET_DESCS] = {
3365		.key = ILLEGAL_REQUEST,
3366		.asc = 0x26,
3367		.ascq = 0x06, /* TOO MANY TARGET DESCRIPTORS */
3368	},
3369	[TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE] = {
3370		.key = ILLEGAL_REQUEST,
3371		.asc = 0x26,
3372		.ascq = 0x07, /* UNSUPPORTED TARGET DESCRIPTOR TYPE CODE */
3373	},
3374	[TCM_TOO_MANY_SEGMENT_DESCS] = {
3375		.key = ILLEGAL_REQUEST,
3376		.asc = 0x26,
3377		.ascq = 0x08, /* TOO MANY SEGMENT DESCRIPTORS */
3378	},
3379	[TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE] = {
3380		.key = ILLEGAL_REQUEST,
3381		.asc = 0x26,
3382		.ascq = 0x09, /* UNSUPPORTED SEGMENT DESCRIPTOR TYPE CODE */
3383	},
3384	[TCM_PARAMETER_LIST_LENGTH_ERROR] = {
3385		.key = ILLEGAL_REQUEST,
3386		.asc = 0x1a, /* PARAMETER LIST LENGTH ERROR */
3387	},
3388	[TCM_UNEXPECTED_UNSOLICITED_DATA] = {
3389		.key = ILLEGAL_REQUEST,
3390		.asc = 0x0c, /* WRITE ERROR */
3391		.ascq = 0x0c, /* UNEXPECTED_UNSOLICITED_DATA */
3392	},
3393	[TCM_SERVICE_CRC_ERROR] = {
3394		.key = ABORTED_COMMAND,
3395		.asc = 0x47, /* PROTOCOL SERVICE CRC ERROR */
3396		.ascq = 0x05, /* N/A */
3397	},
3398	[TCM_SNACK_REJECTED] = {
3399		.key = ABORTED_COMMAND,
3400		.asc = 0x11, /* READ ERROR */
3401		.ascq = 0x13, /* FAILED RETRANSMISSION REQUEST */
3402	},
3403	[TCM_WRITE_PROTECTED] = {
3404		.key = DATA_PROTECT,
3405		.asc = 0x27, /* WRITE PROTECTED */
3406	},
3407	[TCM_ADDRESS_OUT_OF_RANGE] = {
3408		.key = ILLEGAL_REQUEST,
3409		.asc = 0x21, /* LOGICAL BLOCK ADDRESS OUT OF RANGE */
3410	},
3411	[TCM_CHECK_CONDITION_UNIT_ATTENTION] = {
3412		.key = UNIT_ATTENTION,
3413	},
3414	[TCM_MISCOMPARE_VERIFY] = {
3415		.key = MISCOMPARE,
3416		.asc = 0x1d, /* MISCOMPARE DURING VERIFY OPERATION */
3417		.ascq = 0x00,
3418		.add_sense_info = true,
3419	},
3420	[TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED] = {
3421		.key = ABORTED_COMMAND,
3422		.asc = 0x10,
3423		.ascq = 0x01, /* LOGICAL BLOCK GUARD CHECK FAILED */
3424		.add_sense_info = true,
3425	},
3426	[TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED] = {
3427		.key = ABORTED_COMMAND,
3428		.asc = 0x10,
3429		.ascq = 0x02, /* LOGICAL BLOCK APPLICATION TAG CHECK FAILED */
3430		.add_sense_info = true,
3431	},
3432	[TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED] = {
3433		.key = ABORTED_COMMAND,
3434		.asc = 0x10,
3435		.ascq = 0x03, /* LOGICAL BLOCK REFERENCE TAG CHECK FAILED */
3436		.add_sense_info = true,
3437	},
3438	[TCM_COPY_TARGET_DEVICE_NOT_REACHABLE] = {
3439		.key = COPY_ABORTED,
3440		.asc = 0x0d,
3441		.ascq = 0x02, /* COPY TARGET DEVICE NOT REACHABLE */
3442
3443	},
3444	[TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE] = {
3445		/*
3446		 * Returning ILLEGAL REQUEST would cause immediate IO errors on
3447		 * Solaris initiators.  Returning NOT READY instead means the
3448		 * operations will be retried a finite number of times and we
3449		 * can survive intermittent errors.
3450		 */
3451		.key = NOT_READY,
3452		.asc = 0x08, /* LOGICAL UNIT COMMUNICATION FAILURE */
3453	},
3454	[TCM_INSUFFICIENT_REGISTRATION_RESOURCES] = {
3455		/*
3456		 * From spc4r22 section5.7.7,5.7.8
3457		 * If a PERSISTENT RESERVE OUT command with a REGISTER service action
3458		 * or a REGISTER AND IGNORE EXISTING KEY service action or
3459		 * REGISTER AND MOVE service actionis attempted,
3460		 * but there are insufficient device server resources to complete the
3461		 * operation, then the command shall be terminated with CHECK CONDITION
3462		 * status, with the sense key set to ILLEGAL REQUEST,and the additonal
3463		 * sense code set to INSUFFICIENT REGISTRATION RESOURCES.
3464		 */
3465		.key = ILLEGAL_REQUEST,
3466		.asc = 0x55,
3467		.ascq = 0x04, /* INSUFFICIENT REGISTRATION RESOURCES */
3468	},
3469	[TCM_INVALID_FIELD_IN_COMMAND_IU] = {
3470		.key = ILLEGAL_REQUEST,
3471		.asc = 0x0e,
3472		.ascq = 0x03, /* INVALID FIELD IN COMMAND INFORMATION UNIT */
3473	},
3474	[TCM_ALUA_TG_PT_STANDBY] = {
3475		.key = NOT_READY,
3476		.asc = 0x04,
3477		.ascq = ASCQ_04H_ALUA_TG_PT_STANDBY,
3478	},
3479	[TCM_ALUA_TG_PT_UNAVAILABLE] = {
3480		.key = NOT_READY,
3481		.asc = 0x04,
3482		.ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE,
3483	},
3484	[TCM_ALUA_STATE_TRANSITION] = {
3485		.key = NOT_READY,
3486		.asc = 0x04,
3487		.ascq = ASCQ_04H_ALUA_STATE_TRANSITION,
3488	},
3489	[TCM_ALUA_OFFLINE] = {
3490		.key = NOT_READY,
3491		.asc = 0x04,
3492		.ascq = ASCQ_04H_ALUA_OFFLINE,
3493	},
3494};
3495
3496/**
3497 * translate_sense_reason - translate a sense reason into T10 key, asc and ascq
3498 * @cmd: SCSI command in which the resulting sense buffer or SCSI status will
3499 *   be stored.
3500 * @reason: LIO sense reason code. If this argument has the value
3501 *   TCM_CHECK_CONDITION_UNIT_ATTENTION, try to dequeue a unit attention. If
3502 *   dequeuing a unit attention fails due to multiple commands being processed
3503 *   concurrently, set the command status to BUSY.
3504 *
3505 * Return: 0 upon success or -EINVAL if the sense buffer is too small.
3506 */
3507static void translate_sense_reason(struct se_cmd *cmd, sense_reason_t reason)
3508{
3509	const struct sense_detail *sd;
3510	u8 *buffer = cmd->sense_buffer;
3511	int r = (__force int)reason;
3512	u8 key, asc, ascq;
3513	bool desc_format = target_sense_desc_format(cmd->se_dev);
3514
3515	if (r < ARRAY_SIZE(sense_detail_table) && sense_detail_table[r].key)
3516		sd = &sense_detail_table[r];
3517	else
3518		sd = &sense_detail_table[(__force int)
3519				       TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE];
3520
3521	key = sd->key;
3522	if (reason == TCM_CHECK_CONDITION_UNIT_ATTENTION) {
3523		if (!core_scsi3_ua_for_check_condition(cmd, &key, &asc,
3524						       &ascq)) {
3525			cmd->scsi_status = SAM_STAT_BUSY;
3526			return;
3527		}
3528	} else {
3529		WARN_ON_ONCE(sd->asc == 0);
3530		asc = sd->asc;
3531		ascq = sd->ascq;
3532	}
3533
3534	cmd->se_cmd_flags |= SCF_EMULATED_TASK_SENSE;
3535	cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
3536	cmd->scsi_sense_length  = TRANSPORT_SENSE_BUFFER;
3537	scsi_build_sense_buffer(desc_format, buffer, key, asc, ascq);
3538	if (sd->add_sense_info)
3539		WARN_ON_ONCE(scsi_set_sense_information(buffer,
3540							cmd->scsi_sense_length,
3541							cmd->sense_info) < 0);
3542}
3543
3544int
3545transport_send_check_condition_and_sense(struct se_cmd *cmd,
3546		sense_reason_t reason, int from_transport)
3547{
3548	unsigned long flags;
3549
3550	WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3551
3552	spin_lock_irqsave(&cmd->t_state_lock, flags);
3553	if (cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) {
3554		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3555		return 0;
3556	}
3557	cmd->se_cmd_flags |= SCF_SENT_CHECK_CONDITION;
3558	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3559
3560	if (!from_transport)
3561		translate_sense_reason(cmd, reason);
3562
3563	trace_target_cmd_complete(cmd);
3564	return cmd->se_tfo->queue_status(cmd);
3565}
3566EXPORT_SYMBOL(transport_send_check_condition_and_sense);
3567
3568/**
3569 * target_send_busy - Send SCSI BUSY status back to the initiator
3570 * @cmd: SCSI command for which to send a BUSY reply.
3571 *
3572 * Note: Only call this function if target_submit_cmd*() failed.
3573 */
3574int target_send_busy(struct se_cmd *cmd)
3575{
3576	WARN_ON_ONCE(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB);
3577
3578	cmd->scsi_status = SAM_STAT_BUSY;
3579	trace_target_cmd_complete(cmd);
3580	return cmd->se_tfo->queue_status(cmd);
3581}
3582EXPORT_SYMBOL(target_send_busy);
3583
3584static void target_tmr_work(struct work_struct *work)
3585{
3586	struct se_cmd *cmd = container_of(work, struct se_cmd, work);
3587	struct se_device *dev = cmd->se_dev;
3588	struct se_tmr_req *tmr = cmd->se_tmr_req;
3589	int ret;
3590
3591	if (cmd->transport_state & CMD_T_ABORTED)
3592		goto aborted;
3593
3594	switch (tmr->function) {
3595	case TMR_ABORT_TASK:
3596		core_tmr_abort_task(dev, tmr, cmd->se_sess);
3597		break;
3598	case TMR_ABORT_TASK_SET:
3599	case TMR_CLEAR_ACA:
3600	case TMR_CLEAR_TASK_SET:
3601		tmr->response = TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
3602		break;
3603	case TMR_LUN_RESET:
3604		ret = core_tmr_lun_reset(dev, tmr, NULL, NULL);
3605		tmr->response = (!ret) ? TMR_FUNCTION_COMPLETE :
3606					 TMR_FUNCTION_REJECTED;
3607		if (tmr->response == TMR_FUNCTION_COMPLETE) {
3608			target_dev_ua_allocate(dev, 0x29,
3609					       ASCQ_29H_BUS_DEVICE_RESET_FUNCTION_OCCURRED);
3610		}
3611		break;
3612	case TMR_TARGET_WARM_RESET:
3613		tmr->response = TMR_FUNCTION_REJECTED;
3614		break;
3615	case TMR_TARGET_COLD_RESET:
3616		tmr->response = TMR_FUNCTION_REJECTED;
3617		break;
3618	default:
3619		pr_err("Unknown TMR function: 0x%02x.\n",
3620				tmr->function);
3621		tmr->response = TMR_FUNCTION_REJECTED;
3622		break;
3623	}
3624
3625	if (cmd->transport_state & CMD_T_ABORTED)
3626		goto aborted;
3627
3628	cmd->se_tfo->queue_tm_rsp(cmd);
3629
3630	transport_lun_remove_cmd(cmd);
3631	transport_cmd_check_stop_to_fabric(cmd);
3632	return;
3633
3634aborted:
3635	target_handle_abort(cmd);
3636}
3637
3638int transport_generic_handle_tmr(
3639	struct se_cmd *cmd)
3640{
3641	unsigned long flags;
3642	bool aborted = false;
3643
3644	spin_lock_irqsave(&cmd->se_dev->se_tmr_lock, flags);
3645	list_add_tail(&cmd->se_tmr_req->tmr_list, &cmd->se_dev->dev_tmr_list);
3646	spin_unlock_irqrestore(&cmd->se_dev->se_tmr_lock, flags);
3647
3648	spin_lock_irqsave(&cmd->t_state_lock, flags);
3649	if (cmd->transport_state & CMD_T_ABORTED) {
3650		aborted = true;
3651	} else {
3652		cmd->t_state = TRANSPORT_ISTATE_PROCESSING;
3653		cmd->transport_state |= CMD_T_ACTIVE;
3654	}
3655	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
3656
3657	if (aborted) {
3658		pr_warn_ratelimited("handle_tmr caught CMD_T_ABORTED TMR %d ref_tag: %llu tag: %llu\n",
3659				    cmd->se_tmr_req->function,
3660				    cmd->se_tmr_req->ref_task_tag, cmd->tag);
3661		target_handle_abort(cmd);
3662		return 0;
3663	}
3664
3665	INIT_WORK(&cmd->work, target_tmr_work);
3666	schedule_work(&cmd->work);
3667	return 0;
3668}
3669EXPORT_SYMBOL(transport_generic_handle_tmr);
3670
3671bool
3672target_check_wce(struct se_device *dev)
3673{
3674	bool wce = false;
3675
3676	if (dev->transport->get_write_cache)
3677		wce = dev->transport->get_write_cache(dev);
3678	else if (dev->dev_attrib.emulate_write_cache > 0)
3679		wce = true;
3680
3681	return wce;
3682}
3683
3684bool
3685target_check_fua(struct se_device *dev)
3686{
3687	return target_check_wce(dev) && dev->dev_attrib.emulate_fua_write > 0;
3688}