1 /******************************************************************************* 2 * 3 * This file contains the Linux/SCSI LLD virtual SCSI initiator driver 4 * for emulated SAS initiator ports 5 * 6 * © Copyright 2011-2013 Datera, Inc. 7 * 8 * Licensed to the Linux Foundation under the General Public License (GPL) version 2. 9 * 10 * Author: Nicholas A. Bellinger <nab@risingtidesystems.com> 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation; either version 2 of the License, or 15 * (at your option) any later version. 16 * 17 * This program is distributed in the hope that it will be useful, 18 * but WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 20 * GNU General Public License for more details. 21 ****************************************************************************/ 22 23 #include <linux/module.h> 24 #include <linux/moduleparam.h> 25 #include <linux/init.h> 26 #include <linux/slab.h> 27 #include <linux/types.h> 28 #include <linux/configfs.h> 29 #include <linux/blk-mq.h> 30 #include <scsi/scsi.h> 31 #include <scsi/scsi_tcq.h> 32 #include <scsi/scsi_host.h> 33 #include <scsi/scsi_device.h> 34 #include <scsi/scsi_cmnd.h> 35 36 #include <target/target_core_base.h> 37 #include <target/target_core_fabric.h> 38 39 #include "tcm_loop.h" 40 41 #define to_tcm_loop_hba(hba) container_of(hba, struct tcm_loop_hba, dev) 42 43 static struct kmem_cache *tcm_loop_cmd_cache; 44 45 static int tcm_loop_hba_no_cnt; 46 47 static int tcm_loop_queue_status(struct se_cmd *se_cmd); 48 49 static unsigned int tcm_loop_nr_hw_queues = 1; 50 module_param_named(nr_hw_queues, tcm_loop_nr_hw_queues, uint, 0644); 51 52 static unsigned int tcm_loop_can_queue = 1024; 53 module_param_named(can_queue, tcm_loop_can_queue, uint, 0644); 54 55 static unsigned int tcm_loop_cmd_per_lun = 1024; 56 module_param_named(cmd_per_lun, tcm_loop_cmd_per_lun, uint, 0644); 57 58 /* 59 * Called from struct target_core_fabric_ops->check_stop_free() 60 */ 61 static int tcm_loop_check_stop_free(struct se_cmd *se_cmd) 62 { 63 return transport_generic_free_cmd(se_cmd, 0); 64 } 65 66 static void tcm_loop_release_cmd(struct se_cmd *se_cmd) 67 { 68 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd, 69 struct tcm_loop_cmd, tl_se_cmd); 70 struct scsi_cmnd *sc = tl_cmd->sc; 71 72 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) 73 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd); 74 else 75 scsi_done(sc); 76 } 77 78 static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host) 79 { 80 seq_puts(m, "tcm_loop_proc_info()\n"); 81 return 0; 82 } 83 84 static int tcm_loop_driver_probe(struct device *); 85 static void tcm_loop_driver_remove(struct device *); 86 87 static const struct bus_type tcm_loop_lld_bus = { 88 .name = "tcm_loop_bus", 89 .probe = tcm_loop_driver_probe, 90 .remove = tcm_loop_driver_remove, 91 }; 92 93 static struct device_driver tcm_loop_driverfs = { 94 .name = "tcm_loop", 95 .bus = &tcm_loop_lld_bus, 96 }; 97 /* 98 * Used with root_device_register() in tcm_loop_alloc_core_bus() below 99 */ 100 static struct device *tcm_loop_primary; 101 102 static void tcm_loop_target_queue_cmd(struct tcm_loop_cmd *tl_cmd) 103 { 104 struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd; 105 struct scsi_cmnd *sc = tl_cmd->sc; 106 struct tcm_loop_nexus *tl_nexus; 107 struct tcm_loop_hba *tl_hba; 108 struct tcm_loop_tpg *tl_tpg; 109 struct scatterlist *sgl_bidi = NULL; 110 u32 sgl_bidi_count = 0, transfer_length; 111 112 tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host); 113 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id]; 114 115 /* 116 * Ensure that this tl_tpg reference from the incoming sc->device->id 117 * has already been configured via tcm_loop_make_naa_tpg(). 118 */ 119 if (!tl_tpg->tl_hba) { 120 set_host_byte(sc, DID_NO_CONNECT); 121 goto out_done; 122 } 123 if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) { 124 set_host_byte(sc, DID_TRANSPORT_DISRUPTED); 125 goto out_done; 126 } 127 tl_nexus = tl_tpg->tl_nexus; 128 if (!tl_nexus) { 129 scmd_printk(KERN_ERR, sc, 130 "TCM_Loop I_T Nexus does not exist\n"); 131 set_host_byte(sc, DID_ERROR); 132 goto out_done; 133 } 134 135 transfer_length = scsi_transfer_length(sc); 136 if (!scsi_prot_sg_count(sc) && 137 scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) { 138 se_cmd->prot_pto = true; 139 /* 140 * loopback transport doesn't support 141 * WRITE_GENERATE, READ_STRIP protection 142 * information operations, go ahead unprotected. 143 */ 144 transfer_length = scsi_bufflen(sc); 145 } 146 147 se_cmd->tag = tl_cmd->sc_cmd_tag; 148 target_init_cmd(se_cmd, tl_nexus->se_sess, &tl_cmd->tl_sense_buf[0], 149 tl_cmd->sc->device->lun, transfer_length, 150 TCM_SIMPLE_TAG, sc->sc_data_direction, 0); 151 152 if (target_submit_prep(se_cmd, sc->cmnd, scsi_sglist(sc), 153 scsi_sg_count(sc), sgl_bidi, sgl_bidi_count, 154 scsi_prot_sglist(sc), scsi_prot_sg_count(sc), 155 GFP_ATOMIC)) 156 return; 157 158 target_submit(se_cmd); 159 return; 160 161 out_done: 162 scsi_done(sc); 163 } 164 165 /* 166 * ->queuecommand can be and usually is called from interrupt context, so 167 * defer the actual submission to a workqueue. 168 */ 169 static enum scsi_qc_status tcm_loop_queuecommand(struct Scsi_Host *sh, 170 struct scsi_cmnd *sc) 171 { 172 struct tcm_loop_cmd *tl_cmd = scsi_cmd_priv(sc); 173 174 pr_debug("%s() %d:%d:%d:%llu got CDB: 0x%02x scsi_buf_len: %u\n", 175 __func__, sc->device->host->host_no, sc->device->id, 176 sc->device->channel, sc->device->lun, sc->cmnd[0], 177 scsi_bufflen(sc)); 178 179 memset(tl_cmd, 0, sizeof(*tl_cmd)); 180 tl_cmd->sc = sc; 181 tl_cmd->sc_cmd_tag = blk_mq_unique_tag(scsi_cmd_to_rq(sc)); 182 183 tcm_loop_target_queue_cmd(tl_cmd); 184 return 0; 185 } 186 187 /* 188 * Called from SCSI EH process context to issue a LUN_RESET TMR 189 * to struct scsi_device 190 */ 191 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg, 192 u64 lun, int task, enum tcm_tmreq_table tmr) 193 { 194 struct se_cmd *se_cmd; 195 struct se_session *se_sess; 196 struct tcm_loop_nexus *tl_nexus; 197 struct tcm_loop_cmd *tl_cmd; 198 int ret = TMR_FUNCTION_FAILED, rc; 199 200 /* 201 * Locate the tl_nexus and se_sess pointers 202 */ 203 tl_nexus = tl_tpg->tl_nexus; 204 if (!tl_nexus) { 205 pr_err("Unable to perform device reset without active I_T Nexus\n"); 206 return ret; 207 } 208 209 tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL); 210 if (!tl_cmd) 211 return ret; 212 213 init_completion(&tl_cmd->tmr_done); 214 215 se_cmd = &tl_cmd->tl_se_cmd; 216 se_sess = tl_tpg->tl_nexus->se_sess; 217 218 rc = target_submit_tmr(se_cmd, se_sess, tl_cmd->tl_sense_buf, lun, 219 NULL, tmr, GFP_KERNEL, task, 220 TARGET_SCF_ACK_KREF); 221 if (rc < 0) 222 goto release; 223 wait_for_completion(&tl_cmd->tmr_done); 224 ret = se_cmd->se_tmr_req->response; 225 target_put_sess_cmd(se_cmd); 226 227 out: 228 return ret; 229 230 release: 231 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd); 232 goto out; 233 } 234 235 static int tcm_loop_abort_task(struct scsi_cmnd *sc) 236 { 237 struct tcm_loop_hba *tl_hba; 238 struct tcm_loop_tpg *tl_tpg; 239 int ret; 240 241 /* 242 * Locate the tcm_loop_hba_t pointer 243 */ 244 tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host); 245 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id]; 246 ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun, 247 blk_mq_unique_tag(scsi_cmd_to_rq(sc)), 248 TMR_ABORT_TASK); 249 return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED; 250 } 251 252 /* 253 * Called from SCSI EH process context to issue a LUN_RESET TMR 254 * to struct scsi_device 255 */ 256 static int tcm_loop_device_reset(struct scsi_cmnd *sc) 257 { 258 struct tcm_loop_hba *tl_hba; 259 struct tcm_loop_tpg *tl_tpg; 260 int ret; 261 262 /* 263 * Locate the tcm_loop_hba_t pointer 264 */ 265 tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host); 266 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id]; 267 268 ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun, 269 0, TMR_LUN_RESET); 270 return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED; 271 } 272 273 static bool tcm_loop_flush_work_iter(struct request *rq, void *data) 274 { 275 struct scsi_cmnd *sc = blk_mq_rq_to_pdu(rq); 276 struct tcm_loop_cmd *tl_cmd = scsi_cmd_priv(sc); 277 struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd; 278 279 flush_work(&se_cmd->work); 280 return true; 281 } 282 283 static int tcm_loop_target_reset(struct scsi_cmnd *sc) 284 { 285 struct tcm_loop_hba *tl_hba; 286 struct tcm_loop_tpg *tl_tpg; 287 struct Scsi_Host *sh = sc->device->host; 288 int ret; 289 290 /* 291 * Locate the tcm_loop_hba_t pointer 292 */ 293 tl_hba = *(struct tcm_loop_hba **)shost_priv(sh); 294 if (!tl_hba) { 295 pr_err("Unable to perform device reset without active I_T Nexus\n"); 296 return FAILED; 297 } 298 /* 299 * Locate the tl_tpg pointer from TargetID in sc->device->id 300 */ 301 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id]; 302 if (!tl_tpg) 303 return FAILED; 304 305 /* 306 * Issue a LUN_RESET to drain all commands that the target core 307 * knows about. This handles commands not yet marked CMD_T_COMPLETE. 308 */ 309 ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun, 0, TMR_LUN_RESET); 310 if (ret != TMR_FUNCTION_COMPLETE) 311 return FAILED; 312 313 /* 314 * Flush any deferred target core completion work that may still be 315 * queued. Commands that already had CMD_T_COMPLETE set before the TMR 316 * are skipped by the TMR drain, but their async completion work 317 * (transport_lun_remove_cmd → percpu_ref_put, release_cmd → scsi_done) 318 * may still be pending in target_completion_wq. 319 * 320 * The SCSI EH will reuse in-flight scsi_cmnd structures for recovery 321 * commands (e.g. TUR) immediately after this handler returns SUCCESS — 322 * if deferred work is still pending, the memset in queuecommand would 323 * zero the se_cmd while the work accesses it, leaking the LUN 324 * percpu_ref and hanging configfs unlink forever. 325 * 326 * Use blk_mq_tagset_busy_iter() to find all started requests and 327 * flush_work() on each — the same pattern used by mpi3mr, scsi_debug, 328 * and other SCSI drivers to drain outstanding commands during reset. 329 */ 330 blk_mq_tagset_busy_iter(&sh->tag_set, tcm_loop_flush_work_iter, NULL); 331 332 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE; 333 return SUCCESS; 334 } 335 336 static const struct scsi_host_template tcm_loop_driver_template = { 337 .show_info = tcm_loop_show_info, 338 .proc_name = "tcm_loopback", 339 .name = "TCM_Loopback", 340 .queuecommand = tcm_loop_queuecommand, 341 .change_queue_depth = scsi_change_queue_depth, 342 .eh_abort_handler = tcm_loop_abort_task, 343 .eh_device_reset_handler = tcm_loop_device_reset, 344 .eh_target_reset_handler = tcm_loop_target_reset, 345 .this_id = -1, 346 .sg_tablesize = 256, 347 .max_sectors = 0xFFFF, 348 .dma_boundary = PAGE_SIZE - 1, 349 .module = THIS_MODULE, 350 .track_queue_depth = 1, 351 .cmd_size = sizeof(struct tcm_loop_cmd), 352 }; 353 354 static int tcm_loop_driver_probe(struct device *dev) 355 { 356 struct tcm_loop_hba *tl_hba; 357 struct Scsi_Host *sh; 358 int error, host_prot; 359 360 tl_hba = to_tcm_loop_hba(dev); 361 362 sh = scsi_host_alloc(&tcm_loop_driver_template, 363 sizeof(struct tcm_loop_hba)); 364 if (!sh) { 365 pr_err("Unable to allocate struct scsi_host\n"); 366 return -ENODEV; 367 } 368 tl_hba->sh = sh; 369 370 /* 371 * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata 372 */ 373 *((struct tcm_loop_hba **)sh->hostdata) = tl_hba; 374 /* 375 * Setup single ID, Channel and LUN for now.. 376 */ 377 sh->max_id = 2; 378 sh->max_lun = 0; 379 sh->max_channel = 0; 380 sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE; 381 sh->nr_hw_queues = tcm_loop_nr_hw_queues; 382 sh->can_queue = tcm_loop_can_queue; 383 sh->cmd_per_lun = tcm_loop_cmd_per_lun; 384 385 host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION | 386 SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION | 387 SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION; 388 389 scsi_host_set_prot(sh, host_prot); 390 scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC); 391 392 error = scsi_add_host(sh, &tl_hba->dev); 393 if (error) { 394 pr_err("%s: scsi_add_host failed\n", __func__); 395 scsi_host_put(sh); 396 tl_hba->sh = NULL; 397 return -ENODEV; 398 } 399 return 0; 400 } 401 402 static void tcm_loop_driver_remove(struct device *dev) 403 { 404 struct tcm_loop_hba *tl_hba; 405 struct Scsi_Host *sh; 406 407 tl_hba = to_tcm_loop_hba(dev); 408 sh = tl_hba->sh; 409 410 if (sh) { 411 scsi_remove_host(sh); 412 scsi_host_put(sh); 413 } 414 } 415 416 static void tcm_loop_release_adapter(struct device *dev) 417 { 418 struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev); 419 420 kfree(tl_hba); 421 } 422 423 /* 424 * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c 425 */ 426 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id) 427 { 428 int ret; 429 430 tl_hba->dev.bus = &tcm_loop_lld_bus; 431 tl_hba->dev.parent = tcm_loop_primary; 432 tl_hba->dev.release = &tcm_loop_release_adapter; 433 dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id); 434 435 ret = device_register(&tl_hba->dev); 436 if (ret) { 437 pr_err("device_register() failed for tl_hba->dev: %d\n", ret); 438 put_device(&tl_hba->dev); 439 return -ENODEV; 440 } 441 442 if (!tl_hba->sh) { 443 device_unregister(&tl_hba->dev); 444 return -ENODEV; 445 } 446 447 return 0; 448 } 449 450 /* 451 * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated 452 * tcm_loop SCSI bus. 453 */ 454 static int tcm_loop_alloc_core_bus(void) 455 { 456 int ret; 457 458 tcm_loop_primary = root_device_register("tcm_loop_0"); 459 if (IS_ERR(tcm_loop_primary)) { 460 pr_err("Unable to allocate tcm_loop_primary\n"); 461 return PTR_ERR(tcm_loop_primary); 462 } 463 464 ret = bus_register(&tcm_loop_lld_bus); 465 if (ret) { 466 pr_err("bus_register() failed for tcm_loop_lld_bus\n"); 467 goto dev_unreg; 468 } 469 470 ret = driver_register(&tcm_loop_driverfs); 471 if (ret) { 472 pr_err("driver_register() failed for tcm_loop_driverfs\n"); 473 goto bus_unreg; 474 } 475 476 pr_debug("Initialized TCM Loop Core Bus\n"); 477 return ret; 478 479 bus_unreg: 480 bus_unregister(&tcm_loop_lld_bus); 481 dev_unreg: 482 root_device_unregister(tcm_loop_primary); 483 return ret; 484 } 485 486 static void tcm_loop_release_core_bus(void) 487 { 488 driver_unregister(&tcm_loop_driverfs); 489 bus_unregister(&tcm_loop_lld_bus); 490 root_device_unregister(tcm_loop_primary); 491 492 pr_debug("Releasing TCM Loop Core BUS\n"); 493 } 494 495 static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg) 496 { 497 return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg); 498 } 499 500 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg) 501 { 502 /* 503 * Return the passed NAA identifier for the Target Port 504 */ 505 return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0]; 506 } 507 508 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg) 509 { 510 /* 511 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83 512 * to represent the SCSI Target Port. 513 */ 514 return tl_tpg(se_tpg)->tl_tpgt; 515 } 516 517 /* 518 * Returning (1) here allows for target_core_mod struct se_node_acl to be generated 519 * based upon the incoming fabric dependent SCSI Initiator Port 520 */ 521 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg) 522 { 523 return 1; 524 } 525 526 static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg) 527 { 528 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, 529 tl_se_tpg); 530 return tl_tpg->tl_fabric_prot_type; 531 } 532 533 static u32 tcm_loop_sess_get_index(struct se_session *se_sess) 534 { 535 return 1; 536 } 537 538 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd) 539 { 540 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd, 541 struct tcm_loop_cmd, tl_se_cmd); 542 543 return tl_cmd->sc_cmd_state; 544 } 545 546 static int tcm_loop_write_pending(struct se_cmd *se_cmd) 547 { 548 /* 549 * Since Linux/SCSI has already sent down a struct scsi_cmnd 550 * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array 551 * memory, and memory has already been mapped to struct se_cmd->t_mem_list 552 * format with transport_generic_map_mem_to_cmd(). 553 * 554 * We now tell TCM to add this WRITE CDB directly into the TCM storage 555 * object execution queue. 556 */ 557 target_execute_cmd(se_cmd); 558 return 0; 559 } 560 561 static int tcm_loop_queue_data_or_status(const char *func, 562 struct se_cmd *se_cmd, u8 scsi_status) 563 { 564 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd, 565 struct tcm_loop_cmd, tl_se_cmd); 566 struct scsi_cmnd *sc = tl_cmd->sc; 567 568 pr_debug("%s() called for scsi_cmnd: %p cdb: 0x%02x\n", 569 func, sc, sc->cmnd[0]); 570 571 if (se_cmd->sense_buffer && 572 ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) || 573 (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) { 574 575 memcpy(sc->sense_buffer, se_cmd->sense_buffer, 576 SCSI_SENSE_BUFFERSIZE); 577 sc->result = SAM_STAT_CHECK_CONDITION; 578 } else 579 sc->result = scsi_status; 580 581 set_host_byte(sc, DID_OK); 582 if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) || 583 (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT)) 584 scsi_set_resid(sc, se_cmd->residual_count); 585 return 0; 586 } 587 588 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd) 589 { 590 return tcm_loop_queue_data_or_status(__func__, se_cmd, SAM_STAT_GOOD); 591 } 592 593 static int tcm_loop_queue_status(struct se_cmd *se_cmd) 594 { 595 return tcm_loop_queue_data_or_status(__func__, 596 se_cmd, se_cmd->scsi_status); 597 } 598 599 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd) 600 { 601 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd, 602 struct tcm_loop_cmd, tl_se_cmd); 603 604 /* Wake up tcm_loop_issue_tmr(). */ 605 complete(&tl_cmd->tmr_done); 606 } 607 608 static void tcm_loop_aborted_task(struct se_cmd *se_cmd) 609 { 610 return; 611 } 612 613 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba) 614 { 615 switch (tl_hba->tl_proto_id) { 616 case SCSI_PROTOCOL_SAS: 617 return "SAS"; 618 case SCSI_PROTOCOL_FCP: 619 return "FCP"; 620 case SCSI_PROTOCOL_ISCSI: 621 return "iSCSI"; 622 default: 623 break; 624 } 625 626 return "Unknown"; 627 } 628 629 /* Start items for tcm_loop_port_cit */ 630 631 static int tcm_loop_port_link( 632 struct se_portal_group *se_tpg, 633 struct se_lun *lun) 634 { 635 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, 636 struct tcm_loop_tpg, tl_se_tpg); 637 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba; 638 639 atomic_inc_mb(&tl_tpg->tl_tpg_port_count); 640 /* 641 * Add Linux/SCSI struct scsi_device by HCTL 642 */ 643 scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun); 644 645 pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n"); 646 return 0; 647 } 648 649 static void tcm_loop_port_unlink( 650 struct se_portal_group *se_tpg, 651 struct se_lun *se_lun) 652 { 653 struct scsi_device *sd; 654 struct tcm_loop_hba *tl_hba; 655 struct tcm_loop_tpg *tl_tpg; 656 657 tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg); 658 tl_hba = tl_tpg->tl_hba; 659 660 sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt, 661 se_lun->unpacked_lun); 662 if (!sd) { 663 pr_err("Unable to locate struct scsi_device for %d:%d:%llu\n", 664 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun); 665 return; 666 } 667 /* 668 * Remove Linux/SCSI struct scsi_device by HCTL 669 */ 670 scsi_remove_device(sd); 671 scsi_device_put(sd); 672 673 atomic_dec_mb(&tl_tpg->tl_tpg_port_count); 674 675 pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n"); 676 } 677 678 /* End items for tcm_loop_port_cit */ 679 680 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_show( 681 struct config_item *item, char *page) 682 { 683 struct se_portal_group *se_tpg = attrib_to_tpg(item); 684 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, 685 tl_se_tpg); 686 687 return sprintf(page, "%d\n", tl_tpg->tl_fabric_prot_type); 688 } 689 690 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_store( 691 struct config_item *item, const char *page, size_t count) 692 { 693 struct se_portal_group *se_tpg = attrib_to_tpg(item); 694 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, 695 tl_se_tpg); 696 unsigned long val; 697 int ret = kstrtoul(page, 0, &val); 698 699 if (ret) { 700 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret); 701 return ret; 702 } 703 if (val != 0 && val != 1 && val != 3) { 704 pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val); 705 return -EINVAL; 706 } 707 tl_tpg->tl_fabric_prot_type = val; 708 709 return count; 710 } 711 712 CONFIGFS_ATTR(tcm_loop_tpg_attrib_, fabric_prot_type); 713 714 static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = { 715 &tcm_loop_tpg_attrib_attr_fabric_prot_type, 716 NULL, 717 }; 718 719 /* Start items for tcm_loop_nexus_cit */ 720 721 static int tcm_loop_alloc_sess_cb(struct se_portal_group *se_tpg, 722 struct se_session *se_sess, void *p) 723 { 724 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, 725 struct tcm_loop_tpg, tl_se_tpg); 726 727 tl_tpg->tl_nexus = p; 728 return 0; 729 } 730 731 static int tcm_loop_make_nexus( 732 struct tcm_loop_tpg *tl_tpg, 733 const char *name) 734 { 735 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba; 736 struct tcm_loop_nexus *tl_nexus; 737 int ret; 738 739 if (tl_tpg->tl_nexus) { 740 pr_debug("tl_tpg->tl_nexus already exists\n"); 741 return -EEXIST; 742 } 743 744 tl_nexus = kzalloc_obj(*tl_nexus); 745 if (!tl_nexus) 746 return -ENOMEM; 747 748 tl_nexus->se_sess = target_setup_session(&tl_tpg->tl_se_tpg, 0, 0, 749 TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS, 750 name, tl_nexus, tcm_loop_alloc_sess_cb); 751 if (IS_ERR(tl_nexus->se_sess)) { 752 ret = PTR_ERR(tl_nexus->se_sess); 753 kfree(tl_nexus); 754 return ret; 755 } 756 757 pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated %s Initiator Port: %s\n", 758 tcm_loop_dump_proto_id(tl_hba), name); 759 return 0; 760 } 761 762 static int tcm_loop_drop_nexus( 763 struct tcm_loop_tpg *tpg) 764 { 765 struct se_session *se_sess; 766 struct tcm_loop_nexus *tl_nexus; 767 768 tl_nexus = tpg->tl_nexus; 769 if (!tl_nexus) 770 return -ENODEV; 771 772 se_sess = tl_nexus->se_sess; 773 if (!se_sess) 774 return -ENODEV; 775 776 if (atomic_read(&tpg->tl_tpg_port_count)) { 777 pr_err("Unable to remove TCM_Loop I_T Nexus with active TPG port count: %d\n", 778 atomic_read(&tpg->tl_tpg_port_count)); 779 return -EPERM; 780 } 781 782 pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated %s Initiator Port: %s\n", 783 tcm_loop_dump_proto_id(tpg->tl_hba), 784 tl_nexus->se_sess->se_node_acl->initiatorname); 785 /* 786 * Release the SCSI I_T Nexus to the emulated Target Port 787 */ 788 target_remove_session(se_sess); 789 tpg->tl_nexus = NULL; 790 kfree(tl_nexus); 791 return 0; 792 } 793 794 /* End items for tcm_loop_nexus_cit */ 795 796 static ssize_t tcm_loop_tpg_nexus_show(struct config_item *item, char *page) 797 { 798 struct se_portal_group *se_tpg = to_tpg(item); 799 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, 800 struct tcm_loop_tpg, tl_se_tpg); 801 struct tcm_loop_nexus *tl_nexus; 802 ssize_t ret; 803 804 tl_nexus = tl_tpg->tl_nexus; 805 if (!tl_nexus) 806 return -ENODEV; 807 808 ret = snprintf(page, PAGE_SIZE, "%s\n", 809 tl_nexus->se_sess->se_node_acl->initiatorname); 810 811 return ret; 812 } 813 814 static ssize_t tcm_loop_tpg_nexus_store(struct config_item *item, 815 const char *page, size_t count) 816 { 817 struct se_portal_group *se_tpg = to_tpg(item); 818 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, 819 struct tcm_loop_tpg, tl_se_tpg); 820 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba; 821 unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr; 822 int ret; 823 /* 824 * Shutdown the active I_T nexus if 'NULL' is passed.. 825 */ 826 if (!strncmp(page, "NULL", 4)) { 827 ret = tcm_loop_drop_nexus(tl_tpg); 828 return (!ret) ? count : ret; 829 } 830 /* 831 * Otherwise make sure the passed virtual Initiator port WWN matches 832 * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call 833 * tcm_loop_make_nexus() 834 */ 835 if (strlen(page) >= TL_WWN_ADDR_LEN) { 836 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n", 837 page, TL_WWN_ADDR_LEN); 838 return -EINVAL; 839 } 840 snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page); 841 842 ptr = strstr(i_port, "naa."); 843 if (ptr) { 844 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) { 845 pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n", 846 i_port, tcm_loop_dump_proto_id(tl_hba)); 847 return -EINVAL; 848 } 849 port_ptr = &i_port[0]; 850 goto check_newline; 851 } 852 ptr = strstr(i_port, "fc."); 853 if (ptr) { 854 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) { 855 pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n", 856 i_port, tcm_loop_dump_proto_id(tl_hba)); 857 return -EINVAL; 858 } 859 port_ptr = &i_port[3]; /* Skip over "fc." */ 860 goto check_newline; 861 } 862 ptr = strstr(i_port, "iqn."); 863 if (ptr) { 864 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) { 865 pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n", 866 i_port, tcm_loop_dump_proto_id(tl_hba)); 867 return -EINVAL; 868 } 869 port_ptr = &i_port[0]; 870 goto check_newline; 871 } 872 pr_err("Unable to locate prefix for emulated Initiator Port: %s\n", 873 i_port); 874 return -EINVAL; 875 /* 876 * Clear any trailing newline for the NAA WWN 877 */ 878 check_newline: 879 if (i_port[strlen(i_port)-1] == '\n') 880 i_port[strlen(i_port)-1] = '\0'; 881 882 ret = tcm_loop_make_nexus(tl_tpg, port_ptr); 883 if (ret < 0) 884 return ret; 885 886 return count; 887 } 888 889 static ssize_t tcm_loop_tpg_transport_status_show(struct config_item *item, 890 char *page) 891 { 892 struct se_portal_group *se_tpg = to_tpg(item); 893 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, 894 struct tcm_loop_tpg, tl_se_tpg); 895 const char *status = NULL; 896 ssize_t ret = -EINVAL; 897 898 switch (tl_tpg->tl_transport_status) { 899 case TCM_TRANSPORT_ONLINE: 900 status = "online"; 901 break; 902 case TCM_TRANSPORT_OFFLINE: 903 status = "offline"; 904 break; 905 default: 906 break; 907 } 908 909 if (status) 910 ret = snprintf(page, PAGE_SIZE, "%s\n", status); 911 912 return ret; 913 } 914 915 static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item, 916 const char *page, size_t count) 917 { 918 struct se_portal_group *se_tpg = to_tpg(item); 919 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, 920 struct tcm_loop_tpg, tl_se_tpg); 921 922 if (!strncmp(page, "online", 6)) { 923 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE; 924 return count; 925 } 926 if (!strncmp(page, "offline", 7)) { 927 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE; 928 if (tl_tpg->tl_nexus) { 929 struct se_session *tl_sess = tl_tpg->tl_nexus->se_sess; 930 931 core_allocate_nexus_loss_ua(tl_sess->se_node_acl); 932 } 933 return count; 934 } 935 return -EINVAL; 936 } 937 938 static ssize_t tcm_loop_tpg_address_show(struct config_item *item, 939 char *page) 940 { 941 struct se_portal_group *se_tpg = to_tpg(item); 942 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, 943 struct tcm_loop_tpg, tl_se_tpg); 944 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba; 945 946 if (!tl_hba->sh) 947 return -ENODEV; 948 949 return snprintf(page, PAGE_SIZE, "%d:0:%d\n", 950 tl_hba->sh->host_no, tl_tpg->tl_tpgt); 951 } 952 953 CONFIGFS_ATTR(tcm_loop_tpg_, nexus); 954 CONFIGFS_ATTR(tcm_loop_tpg_, transport_status); 955 CONFIGFS_ATTR_RO(tcm_loop_tpg_, address); 956 957 static struct configfs_attribute *tcm_loop_tpg_attrs[] = { 958 &tcm_loop_tpg_attr_nexus, 959 &tcm_loop_tpg_attr_transport_status, 960 &tcm_loop_tpg_attr_address, 961 NULL, 962 }; 963 964 /* Start items for tcm_loop_naa_cit */ 965 966 static struct se_portal_group *tcm_loop_make_naa_tpg(struct se_wwn *wwn, 967 const char *name) 968 { 969 struct tcm_loop_hba *tl_hba = container_of(wwn, 970 struct tcm_loop_hba, tl_hba_wwn); 971 struct tcm_loop_tpg *tl_tpg; 972 int ret; 973 unsigned long tpgt; 974 975 if (strstr(name, "tpgt_") != name) { 976 pr_err("Unable to locate \"tpgt_#\" directory group\n"); 977 return ERR_PTR(-EINVAL); 978 } 979 if (kstrtoul(name+5, 10, &tpgt)) 980 return ERR_PTR(-EINVAL); 981 982 if (tpgt >= TL_TPGS_PER_HBA) { 983 pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA: %u\n", 984 tpgt, TL_TPGS_PER_HBA); 985 return ERR_PTR(-EINVAL); 986 } 987 tl_tpg = &tl_hba->tl_hba_tpgs[tpgt]; 988 tl_tpg->tl_hba = tl_hba; 989 tl_tpg->tl_tpgt = tpgt; 990 /* 991 * Register the tl_tpg as a emulated TCM Target Endpoint 992 */ 993 ret = core_tpg_register(wwn, &tl_tpg->tl_se_tpg, tl_hba->tl_proto_id); 994 if (ret < 0) 995 return ERR_PTR(-ENOMEM); 996 997 pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s Target Port %s,t,0x%04lx\n", 998 tcm_loop_dump_proto_id(tl_hba), 999 config_item_name(&wwn->wwn_group.cg_item), tpgt); 1000 return &tl_tpg->tl_se_tpg; 1001 } 1002 1003 static void tcm_loop_drop_naa_tpg( 1004 struct se_portal_group *se_tpg) 1005 { 1006 struct se_wwn *wwn = se_tpg->se_tpg_wwn; 1007 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, 1008 struct tcm_loop_tpg, tl_se_tpg); 1009 struct tcm_loop_hba *tl_hba; 1010 unsigned short tpgt; 1011 1012 tl_hba = tl_tpg->tl_hba; 1013 tpgt = tl_tpg->tl_tpgt; 1014 /* 1015 * Release the I_T Nexus for the Virtual target link if present 1016 */ 1017 tcm_loop_drop_nexus(tl_tpg); 1018 /* 1019 * Deregister the tl_tpg as a emulated TCM Target Endpoint 1020 */ 1021 core_tpg_deregister(se_tpg); 1022 1023 tl_tpg->tl_hba = NULL; 1024 tl_tpg->tl_tpgt = 0; 1025 1026 pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s Target Port %s,t,0x%04x\n", 1027 tcm_loop_dump_proto_id(tl_hba), 1028 config_item_name(&wwn->wwn_group.cg_item), tpgt); 1029 } 1030 1031 /* End items for tcm_loop_naa_cit */ 1032 1033 /* Start items for tcm_loop_cit */ 1034 1035 static struct se_wwn *tcm_loop_make_scsi_hba( 1036 struct target_fabric_configfs *tf, 1037 struct config_group *group, 1038 const char *name) 1039 { 1040 struct tcm_loop_hba *tl_hba; 1041 struct Scsi_Host *sh; 1042 char *ptr; 1043 int ret, off = 0; 1044 1045 tl_hba = kzalloc_obj(*tl_hba); 1046 if (!tl_hba) 1047 return ERR_PTR(-ENOMEM); 1048 1049 /* 1050 * Determine the emulated Protocol Identifier and Target Port Name 1051 * based on the incoming configfs directory name. 1052 */ 1053 ptr = strstr(name, "naa."); 1054 if (ptr) { 1055 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS; 1056 goto check_len; 1057 } 1058 ptr = strstr(name, "fc."); 1059 if (ptr) { 1060 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP; 1061 off = 3; /* Skip over "fc." */ 1062 goto check_len; 1063 } 1064 ptr = strstr(name, "iqn."); 1065 if (!ptr) { 1066 pr_err("Unable to locate prefix for emulated Target Port: %s\n", 1067 name); 1068 ret = -EINVAL; 1069 goto out; 1070 } 1071 tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI; 1072 1073 check_len: 1074 if (strlen(name) >= TL_WWN_ADDR_LEN) { 1075 pr_err("Emulated NAA %s Address: %s, exceeds max: %d\n", 1076 name, tcm_loop_dump_proto_id(tl_hba), TL_WWN_ADDR_LEN); 1077 ret = -EINVAL; 1078 goto out; 1079 } 1080 snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]); 1081 1082 /* 1083 * Call device_register(tl_hba->dev) to register the emulated 1084 * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after 1085 * device_register() callbacks in tcm_loop_driver_probe() 1086 */ 1087 ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt); 1088 if (ret) 1089 return ERR_PTR(ret); 1090 1091 sh = tl_hba->sh; 1092 tcm_loop_hba_no_cnt++; 1093 pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n", 1094 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no); 1095 return &tl_hba->tl_hba_wwn; 1096 out: 1097 kfree(tl_hba); 1098 return ERR_PTR(ret); 1099 } 1100 1101 static void tcm_loop_drop_scsi_hba( 1102 struct se_wwn *wwn) 1103 { 1104 struct tcm_loop_hba *tl_hba = container_of(wwn, 1105 struct tcm_loop_hba, tl_hba_wwn); 1106 1107 pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n", 1108 tcm_loop_dump_proto_id(tl_hba), tl_hba->tl_wwn_address, 1109 tl_hba->sh->host_no); 1110 /* 1111 * Call device_unregister() on the original tl_hba->dev. 1112 * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will 1113 * release *tl_hba; 1114 */ 1115 device_unregister(&tl_hba->dev); 1116 } 1117 1118 /* Start items for tcm_loop_cit */ 1119 static ssize_t tcm_loop_wwn_version_show(struct config_item *item, char *page) 1120 { 1121 return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION); 1122 } 1123 1124 CONFIGFS_ATTR_RO(tcm_loop_wwn_, version); 1125 1126 static struct configfs_attribute *tcm_loop_wwn_attrs[] = { 1127 &tcm_loop_wwn_attr_version, 1128 NULL, 1129 }; 1130 1131 /* End items for tcm_loop_cit */ 1132 1133 static const struct target_core_fabric_ops loop_ops = { 1134 .module = THIS_MODULE, 1135 .fabric_name = "loopback", 1136 .tpg_get_wwn = tcm_loop_get_endpoint_wwn, 1137 .tpg_get_tag = tcm_loop_get_tag, 1138 .tpg_check_demo_mode = tcm_loop_check_demo_mode, 1139 .tpg_check_prot_fabric_only = tcm_loop_check_prot_fabric_only, 1140 .check_stop_free = tcm_loop_check_stop_free, 1141 .release_cmd = tcm_loop_release_cmd, 1142 .sess_get_index = tcm_loop_sess_get_index, 1143 .write_pending = tcm_loop_write_pending, 1144 .get_cmd_state = tcm_loop_get_cmd_state, 1145 .queue_data_in = tcm_loop_queue_data_in, 1146 .queue_status = tcm_loop_queue_status, 1147 .queue_tm_rsp = tcm_loop_queue_tm_rsp, 1148 .aborted_task = tcm_loop_aborted_task, 1149 .fabric_make_wwn = tcm_loop_make_scsi_hba, 1150 .fabric_drop_wwn = tcm_loop_drop_scsi_hba, 1151 .fabric_make_tpg = tcm_loop_make_naa_tpg, 1152 .fabric_drop_tpg = tcm_loop_drop_naa_tpg, 1153 .fabric_post_link = tcm_loop_port_link, 1154 .fabric_pre_unlink = tcm_loop_port_unlink, 1155 .tfc_wwn_attrs = tcm_loop_wwn_attrs, 1156 .tfc_tpg_base_attrs = tcm_loop_tpg_attrs, 1157 .tfc_tpg_attrib_attrs = tcm_loop_tpg_attrib_attrs, 1158 .default_compl_type = TARGET_QUEUE_COMPL, 1159 .default_submit_type = TARGET_QUEUE_SUBMIT, 1160 .direct_submit_supp = 0, 1161 }; 1162 1163 static int __init tcm_loop_fabric_init(void) 1164 { 1165 int ret = -ENOMEM; 1166 1167 tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache", 1168 sizeof(struct tcm_loop_cmd), 1169 __alignof__(struct tcm_loop_cmd), 1170 0, NULL); 1171 if (!tcm_loop_cmd_cache) { 1172 pr_debug("kmem_cache_create() for tcm_loop_cmd_cache failed\n"); 1173 goto out; 1174 } 1175 1176 ret = tcm_loop_alloc_core_bus(); 1177 if (ret) 1178 goto out_destroy_cache; 1179 1180 ret = target_register_template(&loop_ops); 1181 if (ret) 1182 goto out_release_core_bus; 1183 1184 return 0; 1185 1186 out_release_core_bus: 1187 tcm_loop_release_core_bus(); 1188 out_destroy_cache: 1189 kmem_cache_destroy(tcm_loop_cmd_cache); 1190 out: 1191 return ret; 1192 } 1193 1194 static void __exit tcm_loop_fabric_exit(void) 1195 { 1196 target_unregister_template(&loop_ops); 1197 tcm_loop_release_core_bus(); 1198 kmem_cache_destroy(tcm_loop_cmd_cache); 1199 } 1200 1201 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module"); 1202 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>"); 1203 MODULE_LICENSE("GPL"); 1204 module_init(tcm_loop_fabric_init); 1205 module_exit(tcm_loop_fabric_exit); 1206