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