1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * NVMe over Fabrics loopback device. 4 * Copyright (c) 2015-2016 HGST, a Western Digital Company. 5 */ 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 #include <linux/scatterlist.h> 8 #include <linux/blk-mq.h> 9 #include <linux/nvme.h> 10 #include <linux/module.h> 11 #include <linux/parser.h> 12 #include "nvmet.h" 13 #include "../host/nvme.h" 14 #include "../host/fabrics.h" 15 16 #define NVME_LOOP_MAX_SEGMENTS 256 17 18 struct nvme_loop_iod { 19 struct nvme_request nvme_req; 20 struct nvme_command cmd; 21 struct nvme_completion cqe; 22 struct nvmet_req req; 23 struct nvme_loop_queue *queue; 24 struct work_struct work; 25 struct sg_table sg_table; 26 struct scatterlist first_sgl[]; 27 }; 28 29 struct nvme_loop_ctrl { 30 struct nvme_loop_queue *queues; 31 32 struct blk_mq_tag_set admin_tag_set; 33 34 struct list_head list; 35 struct blk_mq_tag_set tag_set; 36 struct nvme_loop_iod async_event_iod; 37 struct nvme_ctrl ctrl; 38 39 struct nvmet_port *port; 40 }; 41 42 static inline struct nvme_loop_ctrl *to_loop_ctrl(struct nvme_ctrl *ctrl) 43 { 44 return container_of(ctrl, struct nvme_loop_ctrl, ctrl); 45 } 46 47 enum nvme_loop_queue_flags { 48 NVME_LOOP_Q_LIVE = 0, 49 }; 50 51 struct nvme_loop_queue { 52 struct nvmet_cq nvme_cq; 53 struct nvmet_sq nvme_sq; 54 struct nvme_loop_ctrl *ctrl; 55 unsigned long flags; 56 }; 57 58 static LIST_HEAD(nvme_loop_ports); 59 static DEFINE_MUTEX(nvme_loop_ports_mutex); 60 61 static LIST_HEAD(nvme_loop_ctrl_list); 62 static DEFINE_MUTEX(nvme_loop_ctrl_mutex); 63 64 static void nvme_loop_queue_response(struct nvmet_req *nvme_req); 65 static void nvme_loop_delete_ctrl(struct nvmet_ctrl *ctrl); 66 67 static const struct nvmet_fabrics_ops nvme_loop_ops; 68 69 static inline int nvme_loop_queue_idx(struct nvme_loop_queue *queue) 70 { 71 return queue - queue->ctrl->queues; 72 } 73 74 static void nvme_loop_complete_rq(struct request *req) 75 { 76 struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req); 77 78 sg_free_table_chained(&iod->sg_table, NVME_INLINE_SG_CNT); 79 nvme_complete_rq(req); 80 } 81 82 static struct blk_mq_tags *nvme_loop_tagset(struct nvme_loop_queue *queue) 83 { 84 u32 queue_idx = nvme_loop_queue_idx(queue); 85 86 if (queue_idx == 0) 87 return queue->ctrl->admin_tag_set.tags[queue_idx]; 88 return queue->ctrl->tag_set.tags[queue_idx - 1]; 89 } 90 91 static void nvme_loop_queue_response(struct nvmet_req *req) 92 { 93 struct nvme_loop_queue *queue = 94 container_of(req->sq, struct nvme_loop_queue, nvme_sq); 95 struct nvme_completion *cqe = req->cqe; 96 97 /* 98 * AEN requests are special as they don't time out and can 99 * survive any kind of queue freeze and often don't respond to 100 * aborts. We don't even bother to allocate a struct request 101 * for them but rather special case them here. 102 */ 103 if (unlikely(nvme_is_aen_req(nvme_loop_queue_idx(queue), 104 cqe->command_id))) { 105 nvme_complete_async_event(&queue->ctrl->ctrl, cqe->status, 106 &cqe->result); 107 } else { 108 struct request *rq; 109 110 rq = nvme_find_rq(nvme_loop_tagset(queue), cqe->command_id); 111 if (!rq) { 112 dev_err(queue->ctrl->ctrl.device, 113 "got bad command_id %#x on queue %d\n", 114 cqe->command_id, nvme_loop_queue_idx(queue)); 115 return; 116 } 117 118 if (!nvme_try_complete_req(rq, cqe->status, cqe->result)) 119 nvme_loop_complete_rq(rq); 120 } 121 } 122 123 static void nvme_loop_execute_work(struct work_struct *work) 124 { 125 struct nvme_loop_iod *iod = 126 container_of(work, struct nvme_loop_iod, work); 127 128 iod->req.execute(&iod->req); 129 } 130 131 static blk_status_t nvme_loop_queue_rq(struct blk_mq_hw_ctx *hctx, 132 const struct blk_mq_queue_data *bd) 133 { 134 struct nvme_ns *ns = hctx->queue->queuedata; 135 struct nvme_loop_queue *queue = hctx->driver_data; 136 struct request *req = bd->rq; 137 struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req); 138 bool queue_ready = test_bit(NVME_LOOP_Q_LIVE, &queue->flags); 139 blk_status_t ret; 140 141 if (!nvme_check_ready(&queue->ctrl->ctrl, req, queue_ready)) 142 return nvme_fail_nonready_command(&queue->ctrl->ctrl, req); 143 144 ret = nvme_setup_cmd(ns, req); 145 if (ret) 146 return ret; 147 148 nvme_start_request(req); 149 iod->cmd.common.flags |= NVME_CMD_SGL_METABUF; 150 iod->req.port = queue->ctrl->port; 151 if (!nvmet_req_init(&iod->req, &queue->nvme_cq, 152 &queue->nvme_sq, &nvme_loop_ops)) 153 return BLK_STS_OK; 154 155 if (blk_rq_nr_phys_segments(req)) { 156 iod->sg_table.sgl = iod->first_sgl; 157 if (sg_alloc_table_chained(&iod->sg_table, 158 blk_rq_nr_phys_segments(req), 159 iod->sg_table.sgl, NVME_INLINE_SG_CNT)) { 160 nvme_cleanup_cmd(req); 161 return BLK_STS_RESOURCE; 162 } 163 164 iod->req.sg = iod->sg_table.sgl; 165 iod->req.sg_cnt = blk_rq_map_sg(req->q, req, iod->sg_table.sgl); 166 iod->req.transfer_len = blk_rq_payload_bytes(req); 167 } 168 169 queue_work(nvmet_wq, &iod->work); 170 return BLK_STS_OK; 171 } 172 173 static void nvme_loop_submit_async_event(struct nvme_ctrl *arg) 174 { 175 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(arg); 176 struct nvme_loop_queue *queue = &ctrl->queues[0]; 177 struct nvme_loop_iod *iod = &ctrl->async_event_iod; 178 179 memset(&iod->cmd, 0, sizeof(iod->cmd)); 180 iod->cmd.common.opcode = nvme_admin_async_event; 181 iod->cmd.common.command_id = NVME_AQ_BLK_MQ_DEPTH; 182 iod->cmd.common.flags |= NVME_CMD_SGL_METABUF; 183 184 if (!nvmet_req_init(&iod->req, &queue->nvme_cq, &queue->nvme_sq, 185 &nvme_loop_ops)) { 186 dev_err(ctrl->ctrl.device, "failed async event work\n"); 187 return; 188 } 189 190 queue_work(nvmet_wq, &iod->work); 191 } 192 193 static int nvme_loop_init_iod(struct nvme_loop_ctrl *ctrl, 194 struct nvme_loop_iod *iod, unsigned int queue_idx) 195 { 196 iod->req.cmd = &iod->cmd; 197 iod->req.cqe = &iod->cqe; 198 iod->queue = &ctrl->queues[queue_idx]; 199 INIT_WORK(&iod->work, nvme_loop_execute_work); 200 return 0; 201 } 202 203 static int nvme_loop_init_request(struct blk_mq_tag_set *set, 204 struct request *req, unsigned int hctx_idx, 205 unsigned int numa_node) 206 { 207 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(set->driver_data); 208 struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req); 209 210 nvme_req(req)->ctrl = &ctrl->ctrl; 211 nvme_req(req)->cmd = &iod->cmd; 212 return nvme_loop_init_iod(ctrl, blk_mq_rq_to_pdu(req), 213 (set == &ctrl->tag_set) ? hctx_idx + 1 : 0); 214 } 215 216 static struct lock_class_key loop_hctx_fq_lock_key; 217 218 static int nvme_loop_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, 219 unsigned int hctx_idx) 220 { 221 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(data); 222 struct nvme_loop_queue *queue = &ctrl->queues[hctx_idx + 1]; 223 224 BUG_ON(hctx_idx >= ctrl->ctrl.queue_count); 225 226 /* 227 * flush_end_io() can be called recursively for us, so use our own 228 * lock class key for avoiding lockdep possible recursive locking, 229 * then we can remove the dynamically allocated lock class for each 230 * flush queue, that way may cause horrible boot delay. 231 */ 232 blk_mq_hctx_set_fq_lock_class(hctx, &loop_hctx_fq_lock_key); 233 234 hctx->driver_data = queue; 235 return 0; 236 } 237 238 static int nvme_loop_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data, 239 unsigned int hctx_idx) 240 { 241 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(data); 242 struct nvme_loop_queue *queue = &ctrl->queues[0]; 243 244 BUG_ON(hctx_idx != 0); 245 246 hctx->driver_data = queue; 247 return 0; 248 } 249 250 static const struct blk_mq_ops nvme_loop_mq_ops = { 251 .queue_rq = nvme_loop_queue_rq, 252 .complete = nvme_loop_complete_rq, 253 .init_request = nvme_loop_init_request, 254 .init_hctx = nvme_loop_init_hctx, 255 }; 256 257 static const struct blk_mq_ops nvme_loop_admin_mq_ops = { 258 .queue_rq = nvme_loop_queue_rq, 259 .complete = nvme_loop_complete_rq, 260 .init_request = nvme_loop_init_request, 261 .init_hctx = nvme_loop_init_admin_hctx, 262 }; 263 264 static void nvme_loop_destroy_admin_queue(struct nvme_loop_ctrl *ctrl) 265 { 266 if (!test_and_clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags)) 267 return; 268 nvmet_sq_destroy(&ctrl->queues[0].nvme_sq); 269 nvme_remove_admin_tag_set(&ctrl->ctrl); 270 } 271 272 static void nvme_loop_free_ctrl(struct nvme_ctrl *nctrl) 273 { 274 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl); 275 276 if (list_empty(&ctrl->list)) 277 goto free_ctrl; 278 279 mutex_lock(&nvme_loop_ctrl_mutex); 280 list_del(&ctrl->list); 281 mutex_unlock(&nvme_loop_ctrl_mutex); 282 283 if (nctrl->tagset) 284 nvme_remove_io_tag_set(nctrl); 285 kfree(ctrl->queues); 286 nvmf_free_options(nctrl->opts); 287 free_ctrl: 288 kfree(ctrl); 289 } 290 291 static void nvme_loop_destroy_io_queues(struct nvme_loop_ctrl *ctrl) 292 { 293 int i; 294 295 for (i = 1; i < ctrl->ctrl.queue_count; i++) { 296 clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[i].flags); 297 nvmet_sq_destroy(&ctrl->queues[i].nvme_sq); 298 } 299 ctrl->ctrl.queue_count = 1; 300 } 301 302 static int nvme_loop_init_io_queues(struct nvme_loop_ctrl *ctrl) 303 { 304 struct nvmf_ctrl_options *opts = ctrl->ctrl.opts; 305 unsigned int nr_io_queues; 306 int ret, i; 307 308 nr_io_queues = min(opts->nr_io_queues, num_online_cpus()); 309 ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues); 310 if (ret || !nr_io_queues) 311 return ret; 312 313 dev_info(ctrl->ctrl.device, "creating %d I/O queues.\n", nr_io_queues); 314 315 for (i = 1; i <= nr_io_queues; i++) { 316 ctrl->queues[i].ctrl = ctrl; 317 ret = nvmet_sq_init(&ctrl->queues[i].nvme_sq); 318 if (ret) 319 goto out_destroy_queues; 320 321 ctrl->ctrl.queue_count++; 322 } 323 324 return 0; 325 326 out_destroy_queues: 327 nvme_loop_destroy_io_queues(ctrl); 328 return ret; 329 } 330 331 static int nvme_loop_connect_io_queues(struct nvme_loop_ctrl *ctrl) 332 { 333 int i, ret; 334 335 for (i = 1; i < ctrl->ctrl.queue_count; i++) { 336 ret = nvmf_connect_io_queue(&ctrl->ctrl, i); 337 if (ret) 338 return ret; 339 set_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[i].flags); 340 } 341 342 return 0; 343 } 344 345 static int nvme_loop_configure_admin_queue(struct nvme_loop_ctrl *ctrl) 346 { 347 int error; 348 349 ctrl->queues[0].ctrl = ctrl; 350 error = nvmet_sq_init(&ctrl->queues[0].nvme_sq); 351 if (error) 352 return error; 353 ctrl->ctrl.queue_count = 1; 354 355 error = nvme_alloc_admin_tag_set(&ctrl->ctrl, &ctrl->admin_tag_set, 356 &nvme_loop_admin_mq_ops, 357 sizeof(struct nvme_loop_iod) + 358 NVME_INLINE_SG_CNT * sizeof(struct scatterlist)); 359 if (error) 360 goto out_free_sq; 361 362 /* reset stopped state for the fresh admin queue */ 363 clear_bit(NVME_CTRL_ADMIN_Q_STOPPED, &ctrl->ctrl.flags); 364 365 error = nvmf_connect_admin_queue(&ctrl->ctrl); 366 if (error) 367 goto out_cleanup_tagset; 368 369 set_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags); 370 371 error = nvme_enable_ctrl(&ctrl->ctrl); 372 if (error) 373 goto out_cleanup_tagset; 374 375 ctrl->ctrl.max_hw_sectors = 376 (NVME_LOOP_MAX_SEGMENTS - 1) << PAGE_SECTORS_SHIFT; 377 378 nvme_unquiesce_admin_queue(&ctrl->ctrl); 379 380 error = nvme_init_ctrl_finish(&ctrl->ctrl, false); 381 if (error) 382 goto out_cleanup_tagset; 383 384 return 0; 385 386 out_cleanup_tagset: 387 clear_bit(NVME_LOOP_Q_LIVE, &ctrl->queues[0].flags); 388 nvme_remove_admin_tag_set(&ctrl->ctrl); 389 out_free_sq: 390 nvmet_sq_destroy(&ctrl->queues[0].nvme_sq); 391 return error; 392 } 393 394 static void nvme_loop_shutdown_ctrl(struct nvme_loop_ctrl *ctrl) 395 { 396 if (ctrl->ctrl.queue_count > 1) { 397 nvme_quiesce_io_queues(&ctrl->ctrl); 398 nvme_cancel_tagset(&ctrl->ctrl); 399 nvme_loop_destroy_io_queues(ctrl); 400 } 401 402 nvme_quiesce_admin_queue(&ctrl->ctrl); 403 if (nvme_ctrl_state(&ctrl->ctrl) == NVME_CTRL_LIVE) 404 nvme_disable_ctrl(&ctrl->ctrl, true); 405 406 nvme_cancel_admin_tagset(&ctrl->ctrl); 407 nvme_loop_destroy_admin_queue(ctrl); 408 } 409 410 static void nvme_loop_delete_ctrl_host(struct nvme_ctrl *ctrl) 411 { 412 nvme_loop_shutdown_ctrl(to_loop_ctrl(ctrl)); 413 } 414 415 static void nvme_loop_delete_ctrl(struct nvmet_ctrl *nctrl) 416 { 417 struct nvme_loop_ctrl *ctrl; 418 419 mutex_lock(&nvme_loop_ctrl_mutex); 420 list_for_each_entry(ctrl, &nvme_loop_ctrl_list, list) { 421 if (ctrl->ctrl.cntlid == nctrl->cntlid) 422 nvme_delete_ctrl(&ctrl->ctrl); 423 } 424 mutex_unlock(&nvme_loop_ctrl_mutex); 425 } 426 427 static void nvme_loop_reset_ctrl_work(struct work_struct *work) 428 { 429 struct nvme_loop_ctrl *ctrl = 430 container_of(work, struct nvme_loop_ctrl, ctrl.reset_work); 431 int ret; 432 433 nvme_stop_ctrl(&ctrl->ctrl); 434 nvme_loop_shutdown_ctrl(ctrl); 435 436 if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) { 437 enum nvme_ctrl_state state = nvme_ctrl_state(&ctrl->ctrl); 438 439 if (state != NVME_CTRL_DELETING && 440 state != NVME_CTRL_DELETING_NOIO) 441 /* state change failure for non-deleted ctrl? */ 442 WARN_ON_ONCE(1); 443 return; 444 } 445 446 ret = nvme_loop_configure_admin_queue(ctrl); 447 if (ret) 448 goto out_disable; 449 450 ret = nvme_loop_init_io_queues(ctrl); 451 if (ret) 452 goto out_destroy_admin; 453 454 ret = nvme_loop_connect_io_queues(ctrl); 455 if (ret) 456 goto out_destroy_io; 457 458 blk_mq_update_nr_hw_queues(&ctrl->tag_set, 459 ctrl->ctrl.queue_count - 1); 460 461 if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE)) 462 WARN_ON_ONCE(1); 463 464 nvme_start_ctrl(&ctrl->ctrl); 465 466 return; 467 468 out_destroy_io: 469 nvme_loop_destroy_io_queues(ctrl); 470 out_destroy_admin: 471 nvme_quiesce_admin_queue(&ctrl->ctrl); 472 nvme_cancel_admin_tagset(&ctrl->ctrl); 473 nvme_loop_destroy_admin_queue(ctrl); 474 out_disable: 475 dev_warn(ctrl->ctrl.device, "Removing after reset failure\n"); 476 nvme_uninit_ctrl(&ctrl->ctrl); 477 } 478 479 static const struct nvme_ctrl_ops nvme_loop_ctrl_ops = { 480 .name = "loop", 481 .module = THIS_MODULE, 482 .flags = NVME_F_FABRICS, 483 .reg_read32 = nvmf_reg_read32, 484 .reg_read64 = nvmf_reg_read64, 485 .reg_write32 = nvmf_reg_write32, 486 .free_ctrl = nvme_loop_free_ctrl, 487 .submit_async_event = nvme_loop_submit_async_event, 488 .delete_ctrl = nvme_loop_delete_ctrl_host, 489 .get_address = nvmf_get_address, 490 }; 491 492 static int nvme_loop_create_io_queues(struct nvme_loop_ctrl *ctrl) 493 { 494 int ret; 495 496 ret = nvme_loop_init_io_queues(ctrl); 497 if (ret) 498 return ret; 499 500 ret = nvme_alloc_io_tag_set(&ctrl->ctrl, &ctrl->tag_set, 501 &nvme_loop_mq_ops, 1, 502 sizeof(struct nvme_loop_iod) + 503 NVME_INLINE_SG_CNT * sizeof(struct scatterlist)); 504 if (ret) 505 goto out_destroy_queues; 506 507 ret = nvme_loop_connect_io_queues(ctrl); 508 if (ret) 509 goto out_cleanup_tagset; 510 511 return 0; 512 513 out_cleanup_tagset: 514 nvme_remove_io_tag_set(&ctrl->ctrl); 515 out_destroy_queues: 516 nvme_loop_destroy_io_queues(ctrl); 517 return ret; 518 } 519 520 static struct nvmet_port *nvme_loop_find_port(struct nvme_ctrl *ctrl) 521 { 522 struct nvmet_port *p, *found = NULL; 523 524 mutex_lock(&nvme_loop_ports_mutex); 525 list_for_each_entry(p, &nvme_loop_ports, entry) { 526 /* if no transport address is specified use the first port */ 527 if ((ctrl->opts->mask & NVMF_OPT_TRADDR) && 528 strcmp(ctrl->opts->traddr, p->disc_addr.traddr)) 529 continue; 530 found = p; 531 break; 532 } 533 mutex_unlock(&nvme_loop_ports_mutex); 534 return found; 535 } 536 537 static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev, 538 struct nvmf_ctrl_options *opts) 539 { 540 struct nvme_loop_ctrl *ctrl; 541 int ret; 542 543 ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL); 544 if (!ctrl) 545 return ERR_PTR(-ENOMEM); 546 ctrl->ctrl.opts = opts; 547 INIT_LIST_HEAD(&ctrl->list); 548 549 INIT_WORK(&ctrl->ctrl.reset_work, nvme_loop_reset_ctrl_work); 550 551 ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_loop_ctrl_ops, 552 0 /* no quirks, we're perfect! */); 553 if (ret) { 554 kfree(ctrl); 555 goto out; 556 } 557 558 ret = nvme_add_ctrl(&ctrl->ctrl); 559 if (ret) 560 goto out_put_ctrl; 561 562 if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) 563 WARN_ON_ONCE(1); 564 565 ret = -ENOMEM; 566 567 ctrl->ctrl.kato = opts->kato; 568 ctrl->port = nvme_loop_find_port(&ctrl->ctrl); 569 570 ctrl->queues = kcalloc(opts->nr_io_queues + 1, sizeof(*ctrl->queues), 571 GFP_KERNEL); 572 if (!ctrl->queues) 573 goto out_uninit_ctrl; 574 575 ret = nvme_loop_configure_admin_queue(ctrl); 576 if (ret) 577 goto out_free_queues; 578 579 if (opts->queue_size > ctrl->ctrl.maxcmd) { 580 /* warn if maxcmd is lower than queue_size */ 581 dev_warn(ctrl->ctrl.device, 582 "queue_size %zu > ctrl maxcmd %u, clamping down\n", 583 opts->queue_size, ctrl->ctrl.maxcmd); 584 opts->queue_size = ctrl->ctrl.maxcmd; 585 } 586 ctrl->ctrl.sqsize = opts->queue_size - 1; 587 588 if (opts->nr_io_queues) { 589 ret = nvme_loop_create_io_queues(ctrl); 590 if (ret) 591 goto out_remove_admin_queue; 592 } 593 594 nvme_loop_init_iod(ctrl, &ctrl->async_event_iod, 0); 595 596 dev_info(ctrl->ctrl.device, 597 "new ctrl: \"%s\"\n", ctrl->ctrl.opts->subsysnqn); 598 599 if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE)) 600 WARN_ON_ONCE(1); 601 602 mutex_lock(&nvme_loop_ctrl_mutex); 603 list_add_tail(&ctrl->list, &nvme_loop_ctrl_list); 604 mutex_unlock(&nvme_loop_ctrl_mutex); 605 606 nvme_start_ctrl(&ctrl->ctrl); 607 608 return &ctrl->ctrl; 609 610 out_remove_admin_queue: 611 nvme_quiesce_admin_queue(&ctrl->ctrl); 612 nvme_cancel_admin_tagset(&ctrl->ctrl); 613 nvme_loop_destroy_admin_queue(ctrl); 614 out_free_queues: 615 kfree(ctrl->queues); 616 out_uninit_ctrl: 617 nvme_uninit_ctrl(&ctrl->ctrl); 618 out_put_ctrl: 619 nvme_put_ctrl(&ctrl->ctrl); 620 out: 621 if (ret > 0) 622 ret = -EIO; 623 return ERR_PTR(ret); 624 } 625 626 static int nvme_loop_add_port(struct nvmet_port *port) 627 { 628 mutex_lock(&nvme_loop_ports_mutex); 629 list_add_tail(&port->entry, &nvme_loop_ports); 630 mutex_unlock(&nvme_loop_ports_mutex); 631 return 0; 632 } 633 634 static void nvme_loop_remove_port(struct nvmet_port *port) 635 { 636 mutex_lock(&nvme_loop_ports_mutex); 637 list_del_init(&port->entry); 638 mutex_unlock(&nvme_loop_ports_mutex); 639 640 /* 641 * Ensure any ctrls that are in the process of being 642 * deleted are in fact deleted before we return 643 * and free the port. This is to prevent active 644 * ctrls from using a port after it's freed. 645 */ 646 flush_workqueue(nvme_delete_wq); 647 } 648 649 static const struct nvmet_fabrics_ops nvme_loop_ops = { 650 .owner = THIS_MODULE, 651 .type = NVMF_TRTYPE_LOOP, 652 .add_port = nvme_loop_add_port, 653 .remove_port = nvme_loop_remove_port, 654 .queue_response = nvme_loop_queue_response, 655 .delete_ctrl = nvme_loop_delete_ctrl, 656 }; 657 658 static struct nvmf_transport_ops nvme_loop_transport = { 659 .name = "loop", 660 .module = THIS_MODULE, 661 .create_ctrl = nvme_loop_create_ctrl, 662 .allowed_opts = NVMF_OPT_TRADDR, 663 }; 664 665 static int __init nvme_loop_init_module(void) 666 { 667 int ret; 668 669 ret = nvmet_register_transport(&nvme_loop_ops); 670 if (ret) 671 return ret; 672 673 ret = nvmf_register_transport(&nvme_loop_transport); 674 if (ret) 675 nvmet_unregister_transport(&nvme_loop_ops); 676 677 return ret; 678 } 679 680 static void __exit nvme_loop_cleanup_module(void) 681 { 682 struct nvme_loop_ctrl *ctrl, *next; 683 684 nvmf_unregister_transport(&nvme_loop_transport); 685 nvmet_unregister_transport(&nvme_loop_ops); 686 687 mutex_lock(&nvme_loop_ctrl_mutex); 688 list_for_each_entry_safe(ctrl, next, &nvme_loop_ctrl_list, list) 689 nvme_delete_ctrl(&ctrl->ctrl); 690 mutex_unlock(&nvme_loop_ctrl_mutex); 691 692 flush_workqueue(nvme_delete_wq); 693 } 694 695 module_init(nvme_loop_init_module); 696 module_exit(nvme_loop_cleanup_module); 697 698 MODULE_DESCRIPTION("NVMe target loop transport driver"); 699 MODULE_LICENSE("GPL v2"); 700 MODULE_ALIAS("nvmet-transport-254"); /* 254 == NVMF_TRTYPE_LOOP */ 701