1 /* 2 * NVMe over Fabrics loopback device. 3 * Copyright (c) 2015-2016 HGST, a Western Digital Company. 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms and conditions of the GNU General Public License, 7 * version 2, as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 */ 14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 15 #include <linux/scatterlist.h> 16 #include <linux/blk-mq.h> 17 #include <linux/nvme.h> 18 #include <linux/module.h> 19 #include <linux/parser.h> 20 #include "nvmet.h" 21 #include "../host/nvme.h" 22 #include "../host/fabrics.h" 23 24 #define NVME_LOOP_MAX_SEGMENTS 256 25 26 /* 27 * We handle AEN commands ourselves and don't even let the 28 * block layer know about them. 29 */ 30 #define NVME_LOOP_NR_AEN_COMMANDS 1 31 #define NVME_LOOP_AQ_BLKMQ_DEPTH \ 32 (NVME_AQ_DEPTH - NVME_LOOP_NR_AEN_COMMANDS) 33 34 struct nvme_loop_iod { 35 struct nvme_request nvme_req; 36 struct nvme_command cmd; 37 struct nvme_completion rsp; 38 struct nvmet_req req; 39 struct nvme_loop_queue *queue; 40 struct work_struct work; 41 struct sg_table sg_table; 42 struct scatterlist first_sgl[]; 43 }; 44 45 struct nvme_loop_ctrl { 46 struct nvme_loop_queue *queues; 47 u32 queue_count; 48 49 struct blk_mq_tag_set admin_tag_set; 50 51 struct list_head list; 52 u64 cap; 53 struct blk_mq_tag_set tag_set; 54 struct nvme_loop_iod async_event_iod; 55 struct nvme_ctrl ctrl; 56 57 struct nvmet_ctrl *target_ctrl; 58 struct work_struct delete_work; 59 }; 60 61 static inline struct nvme_loop_ctrl *to_loop_ctrl(struct nvme_ctrl *ctrl) 62 { 63 return container_of(ctrl, struct nvme_loop_ctrl, ctrl); 64 } 65 66 struct nvme_loop_queue { 67 struct nvmet_cq nvme_cq; 68 struct nvmet_sq nvme_sq; 69 struct nvme_loop_ctrl *ctrl; 70 }; 71 72 static struct nvmet_port *nvmet_loop_port; 73 74 static LIST_HEAD(nvme_loop_ctrl_list); 75 static DEFINE_MUTEX(nvme_loop_ctrl_mutex); 76 77 static void nvme_loop_queue_response(struct nvmet_req *nvme_req); 78 static void nvme_loop_delete_ctrl(struct nvmet_ctrl *ctrl); 79 80 static struct nvmet_fabrics_ops nvme_loop_ops; 81 82 static inline int nvme_loop_queue_idx(struct nvme_loop_queue *queue) 83 { 84 return queue - queue->ctrl->queues; 85 } 86 87 static void nvme_loop_complete_rq(struct request *req) 88 { 89 struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req); 90 91 nvme_cleanup_cmd(req); 92 sg_free_table_chained(&iod->sg_table, true); 93 nvme_complete_rq(req); 94 } 95 96 static struct blk_mq_tags *nvme_loop_tagset(struct nvme_loop_queue *queue) 97 { 98 u32 queue_idx = nvme_loop_queue_idx(queue); 99 100 if (queue_idx == 0) 101 return queue->ctrl->admin_tag_set.tags[queue_idx]; 102 return queue->ctrl->tag_set.tags[queue_idx - 1]; 103 } 104 105 static void nvme_loop_queue_response(struct nvmet_req *req) 106 { 107 struct nvme_loop_queue *queue = 108 container_of(req->sq, struct nvme_loop_queue, nvme_sq); 109 struct nvme_completion *cqe = req->rsp; 110 111 /* 112 * AEN requests are special as they don't time out and can 113 * survive any kind of queue freeze and often don't respond to 114 * aborts. We don't even bother to allocate a struct request 115 * for them but rather special case them here. 116 */ 117 if (unlikely(nvme_loop_queue_idx(queue) == 0 && 118 cqe->command_id >= NVME_LOOP_AQ_BLKMQ_DEPTH)) { 119 nvme_complete_async_event(&queue->ctrl->ctrl, cqe->status, 120 &cqe->result); 121 } else { 122 struct request *rq; 123 124 rq = blk_mq_tag_to_rq(nvme_loop_tagset(queue), cqe->command_id); 125 if (!rq) { 126 dev_err(queue->ctrl->ctrl.device, 127 "tag 0x%x on queue %d not found\n", 128 cqe->command_id, nvme_loop_queue_idx(queue)); 129 return; 130 } 131 132 nvme_end_request(rq, cqe->status, cqe->result); 133 } 134 } 135 136 static void nvme_loop_execute_work(struct work_struct *work) 137 { 138 struct nvme_loop_iod *iod = 139 container_of(work, struct nvme_loop_iod, work); 140 141 iod->req.execute(&iod->req); 142 } 143 144 static enum blk_eh_timer_return 145 nvme_loop_timeout(struct request *rq, bool reserved) 146 { 147 struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(rq); 148 149 /* queue error recovery */ 150 nvme_reset_ctrl(&iod->queue->ctrl->ctrl); 151 152 /* fail with DNR on admin cmd timeout */ 153 nvme_req(rq)->status = NVME_SC_ABORT_REQ | NVME_SC_DNR; 154 155 return BLK_EH_HANDLED; 156 } 157 158 static blk_status_t nvme_loop_queue_rq(struct blk_mq_hw_ctx *hctx, 159 const struct blk_mq_queue_data *bd) 160 { 161 struct nvme_ns *ns = hctx->queue->queuedata; 162 struct nvme_loop_queue *queue = hctx->driver_data; 163 struct request *req = bd->rq; 164 struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req); 165 blk_status_t ret; 166 167 ret = nvme_setup_cmd(ns, req, &iod->cmd); 168 if (ret) 169 return ret; 170 171 iod->cmd.common.flags |= NVME_CMD_SGL_METABUF; 172 iod->req.port = nvmet_loop_port; 173 if (!nvmet_req_init(&iod->req, &queue->nvme_cq, 174 &queue->nvme_sq, &nvme_loop_ops)) { 175 nvme_cleanup_cmd(req); 176 blk_mq_start_request(req); 177 nvme_loop_queue_response(&iod->req); 178 return BLK_STS_OK; 179 } 180 181 if (blk_rq_bytes(req)) { 182 iod->sg_table.sgl = iod->first_sgl; 183 if (sg_alloc_table_chained(&iod->sg_table, 184 blk_rq_nr_phys_segments(req), 185 iod->sg_table.sgl)) 186 return BLK_STS_RESOURCE; 187 188 iod->req.sg = iod->sg_table.sgl; 189 iod->req.sg_cnt = blk_rq_map_sg(req->q, req, iod->sg_table.sgl); 190 } 191 192 blk_mq_start_request(req); 193 194 schedule_work(&iod->work); 195 return BLK_STS_OK; 196 } 197 198 static void nvme_loop_submit_async_event(struct nvme_ctrl *arg, int aer_idx) 199 { 200 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(arg); 201 struct nvme_loop_queue *queue = &ctrl->queues[0]; 202 struct nvme_loop_iod *iod = &ctrl->async_event_iod; 203 204 memset(&iod->cmd, 0, sizeof(iod->cmd)); 205 iod->cmd.common.opcode = nvme_admin_async_event; 206 iod->cmd.common.command_id = NVME_LOOP_AQ_BLKMQ_DEPTH; 207 iod->cmd.common.flags |= NVME_CMD_SGL_METABUF; 208 209 if (!nvmet_req_init(&iod->req, &queue->nvme_cq, &queue->nvme_sq, 210 &nvme_loop_ops)) { 211 dev_err(ctrl->ctrl.device, "failed async event work\n"); 212 return; 213 } 214 215 schedule_work(&iod->work); 216 } 217 218 static int nvme_loop_init_iod(struct nvme_loop_ctrl *ctrl, 219 struct nvme_loop_iod *iod, unsigned int queue_idx) 220 { 221 iod->req.cmd = &iod->cmd; 222 iod->req.rsp = &iod->rsp; 223 iod->queue = &ctrl->queues[queue_idx]; 224 INIT_WORK(&iod->work, nvme_loop_execute_work); 225 return 0; 226 } 227 228 static int nvme_loop_init_request(struct blk_mq_tag_set *set, 229 struct request *req, unsigned int hctx_idx, 230 unsigned int numa_node) 231 { 232 struct nvme_loop_ctrl *ctrl = set->driver_data; 233 234 return nvme_loop_init_iod(ctrl, blk_mq_rq_to_pdu(req), 235 (set == &ctrl->tag_set) ? hctx_idx + 1 : 0); 236 } 237 238 static int nvme_loop_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, 239 unsigned int hctx_idx) 240 { 241 struct nvme_loop_ctrl *ctrl = data; 242 struct nvme_loop_queue *queue = &ctrl->queues[hctx_idx + 1]; 243 244 BUG_ON(hctx_idx >= ctrl->queue_count); 245 246 hctx->driver_data = queue; 247 return 0; 248 } 249 250 static int nvme_loop_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data, 251 unsigned int hctx_idx) 252 { 253 struct nvme_loop_ctrl *ctrl = data; 254 struct nvme_loop_queue *queue = &ctrl->queues[0]; 255 256 BUG_ON(hctx_idx != 0); 257 258 hctx->driver_data = queue; 259 return 0; 260 } 261 262 static const struct blk_mq_ops nvme_loop_mq_ops = { 263 .queue_rq = nvme_loop_queue_rq, 264 .complete = nvme_loop_complete_rq, 265 .init_request = nvme_loop_init_request, 266 .init_hctx = nvme_loop_init_hctx, 267 .timeout = nvme_loop_timeout, 268 }; 269 270 static const struct blk_mq_ops nvme_loop_admin_mq_ops = { 271 .queue_rq = nvme_loop_queue_rq, 272 .complete = nvme_loop_complete_rq, 273 .init_request = nvme_loop_init_request, 274 .init_hctx = nvme_loop_init_admin_hctx, 275 .timeout = nvme_loop_timeout, 276 }; 277 278 static void nvme_loop_destroy_admin_queue(struct nvme_loop_ctrl *ctrl) 279 { 280 nvmet_sq_destroy(&ctrl->queues[0].nvme_sq); 281 blk_cleanup_queue(ctrl->ctrl.admin_q); 282 blk_mq_free_tag_set(&ctrl->admin_tag_set); 283 } 284 285 static void nvme_loop_free_ctrl(struct nvme_ctrl *nctrl) 286 { 287 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl); 288 289 if (list_empty(&ctrl->list)) 290 goto free_ctrl; 291 292 mutex_lock(&nvme_loop_ctrl_mutex); 293 list_del(&ctrl->list); 294 mutex_unlock(&nvme_loop_ctrl_mutex); 295 296 if (nctrl->tagset) { 297 blk_cleanup_queue(ctrl->ctrl.connect_q); 298 blk_mq_free_tag_set(&ctrl->tag_set); 299 } 300 kfree(ctrl->queues); 301 nvmf_free_options(nctrl->opts); 302 free_ctrl: 303 kfree(ctrl); 304 } 305 306 static void nvme_loop_destroy_io_queues(struct nvme_loop_ctrl *ctrl) 307 { 308 int i; 309 310 for (i = 1; i < ctrl->queue_count; i++) 311 nvmet_sq_destroy(&ctrl->queues[i].nvme_sq); 312 } 313 314 static int nvme_loop_init_io_queues(struct nvme_loop_ctrl *ctrl) 315 { 316 struct nvmf_ctrl_options *opts = ctrl->ctrl.opts; 317 unsigned int nr_io_queues; 318 int ret, i; 319 320 nr_io_queues = min(opts->nr_io_queues, num_online_cpus()); 321 ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues); 322 if (ret || !nr_io_queues) 323 return ret; 324 325 dev_info(ctrl->ctrl.device, "creating %d I/O queues.\n", nr_io_queues); 326 327 for (i = 1; i <= nr_io_queues; i++) { 328 ctrl->queues[i].ctrl = ctrl; 329 ret = nvmet_sq_init(&ctrl->queues[i].nvme_sq); 330 if (ret) 331 goto out_destroy_queues; 332 333 ctrl->queue_count++; 334 } 335 336 return 0; 337 338 out_destroy_queues: 339 nvme_loop_destroy_io_queues(ctrl); 340 return ret; 341 } 342 343 static int nvme_loop_connect_io_queues(struct nvme_loop_ctrl *ctrl) 344 { 345 int i, ret; 346 347 for (i = 1; i < ctrl->queue_count; i++) { 348 ret = nvmf_connect_io_queue(&ctrl->ctrl, i); 349 if (ret) 350 return ret; 351 } 352 353 return 0; 354 } 355 356 static int nvme_loop_configure_admin_queue(struct nvme_loop_ctrl *ctrl) 357 { 358 int error; 359 360 memset(&ctrl->admin_tag_set, 0, sizeof(ctrl->admin_tag_set)); 361 ctrl->admin_tag_set.ops = &nvme_loop_admin_mq_ops; 362 ctrl->admin_tag_set.queue_depth = NVME_LOOP_AQ_BLKMQ_DEPTH; 363 ctrl->admin_tag_set.reserved_tags = 2; /* connect + keep-alive */ 364 ctrl->admin_tag_set.numa_node = NUMA_NO_NODE; 365 ctrl->admin_tag_set.cmd_size = sizeof(struct nvme_loop_iod) + 366 SG_CHUNK_SIZE * sizeof(struct scatterlist); 367 ctrl->admin_tag_set.driver_data = ctrl; 368 ctrl->admin_tag_set.nr_hw_queues = 1; 369 ctrl->admin_tag_set.timeout = ADMIN_TIMEOUT; 370 371 ctrl->queues[0].ctrl = ctrl; 372 error = nvmet_sq_init(&ctrl->queues[0].nvme_sq); 373 if (error) 374 return error; 375 ctrl->queue_count = 1; 376 377 error = blk_mq_alloc_tag_set(&ctrl->admin_tag_set); 378 if (error) 379 goto out_free_sq; 380 381 ctrl->ctrl.admin_q = blk_mq_init_queue(&ctrl->admin_tag_set); 382 if (IS_ERR(ctrl->ctrl.admin_q)) { 383 error = PTR_ERR(ctrl->ctrl.admin_q); 384 goto out_free_tagset; 385 } 386 387 error = nvmf_connect_admin_queue(&ctrl->ctrl); 388 if (error) 389 goto out_cleanup_queue; 390 391 error = nvmf_reg_read64(&ctrl->ctrl, NVME_REG_CAP, &ctrl->cap); 392 if (error) { 393 dev_err(ctrl->ctrl.device, 394 "prop_get NVME_REG_CAP failed\n"); 395 goto out_cleanup_queue; 396 } 397 398 ctrl->ctrl.sqsize = 399 min_t(int, NVME_CAP_MQES(ctrl->cap), ctrl->ctrl.sqsize); 400 401 error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->cap); 402 if (error) 403 goto out_cleanup_queue; 404 405 ctrl->ctrl.max_hw_sectors = 406 (NVME_LOOP_MAX_SEGMENTS - 1) << (PAGE_SHIFT - 9); 407 408 error = nvme_init_identify(&ctrl->ctrl); 409 if (error) 410 goto out_cleanup_queue; 411 412 nvme_start_keep_alive(&ctrl->ctrl); 413 414 return 0; 415 416 out_cleanup_queue: 417 blk_cleanup_queue(ctrl->ctrl.admin_q); 418 out_free_tagset: 419 blk_mq_free_tag_set(&ctrl->admin_tag_set); 420 out_free_sq: 421 nvmet_sq_destroy(&ctrl->queues[0].nvme_sq); 422 return error; 423 } 424 425 static void nvme_loop_shutdown_ctrl(struct nvme_loop_ctrl *ctrl) 426 { 427 nvme_stop_keep_alive(&ctrl->ctrl); 428 429 if (ctrl->queue_count > 1) { 430 nvme_stop_queues(&ctrl->ctrl); 431 blk_mq_tagset_busy_iter(&ctrl->tag_set, 432 nvme_cancel_request, &ctrl->ctrl); 433 nvme_loop_destroy_io_queues(ctrl); 434 } 435 436 if (ctrl->ctrl.state == NVME_CTRL_LIVE) 437 nvme_shutdown_ctrl(&ctrl->ctrl); 438 439 blk_mq_stop_hw_queues(ctrl->ctrl.admin_q); 440 blk_mq_tagset_busy_iter(&ctrl->admin_tag_set, 441 nvme_cancel_request, &ctrl->ctrl); 442 nvme_loop_destroy_admin_queue(ctrl); 443 } 444 445 static void nvme_loop_del_ctrl_work(struct work_struct *work) 446 { 447 struct nvme_loop_ctrl *ctrl = container_of(work, 448 struct nvme_loop_ctrl, delete_work); 449 450 nvme_uninit_ctrl(&ctrl->ctrl); 451 nvme_loop_shutdown_ctrl(ctrl); 452 nvme_put_ctrl(&ctrl->ctrl); 453 } 454 455 static int __nvme_loop_del_ctrl(struct nvme_loop_ctrl *ctrl) 456 { 457 if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING)) 458 return -EBUSY; 459 460 if (!queue_work(nvme_wq, &ctrl->delete_work)) 461 return -EBUSY; 462 463 return 0; 464 } 465 466 static int nvme_loop_del_ctrl(struct nvme_ctrl *nctrl) 467 { 468 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl); 469 int ret; 470 471 ret = __nvme_loop_del_ctrl(ctrl); 472 if (ret) 473 return ret; 474 475 flush_work(&ctrl->delete_work); 476 477 return 0; 478 } 479 480 static void nvme_loop_delete_ctrl(struct nvmet_ctrl *nctrl) 481 { 482 struct nvme_loop_ctrl *ctrl; 483 484 mutex_lock(&nvme_loop_ctrl_mutex); 485 list_for_each_entry(ctrl, &nvme_loop_ctrl_list, list) { 486 if (ctrl->ctrl.cntlid == nctrl->cntlid) 487 __nvme_loop_del_ctrl(ctrl); 488 } 489 mutex_unlock(&nvme_loop_ctrl_mutex); 490 } 491 492 static void nvme_loop_reset_ctrl_work(struct work_struct *work) 493 { 494 struct nvme_loop_ctrl *ctrl = 495 container_of(work, struct nvme_loop_ctrl, ctrl.reset_work); 496 bool changed; 497 int ret; 498 499 nvme_loop_shutdown_ctrl(ctrl); 500 501 ret = nvme_loop_configure_admin_queue(ctrl); 502 if (ret) 503 goto out_disable; 504 505 ret = nvme_loop_init_io_queues(ctrl); 506 if (ret) 507 goto out_destroy_admin; 508 509 ret = nvme_loop_connect_io_queues(ctrl); 510 if (ret) 511 goto out_destroy_io; 512 513 changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE); 514 WARN_ON_ONCE(!changed); 515 516 nvme_queue_scan(&ctrl->ctrl); 517 nvme_queue_async_events(&ctrl->ctrl); 518 519 nvme_start_queues(&ctrl->ctrl); 520 521 return; 522 523 out_destroy_io: 524 nvme_loop_destroy_io_queues(ctrl); 525 out_destroy_admin: 526 nvme_loop_destroy_admin_queue(ctrl); 527 out_disable: 528 dev_warn(ctrl->ctrl.device, "Removing after reset failure\n"); 529 nvme_uninit_ctrl(&ctrl->ctrl); 530 nvme_put_ctrl(&ctrl->ctrl); 531 } 532 533 static const struct nvme_ctrl_ops nvme_loop_ctrl_ops = { 534 .name = "loop", 535 .module = THIS_MODULE, 536 .flags = NVME_F_FABRICS, 537 .reg_read32 = nvmf_reg_read32, 538 .reg_read64 = nvmf_reg_read64, 539 .reg_write32 = nvmf_reg_write32, 540 .free_ctrl = nvme_loop_free_ctrl, 541 .submit_async_event = nvme_loop_submit_async_event, 542 .delete_ctrl = nvme_loop_del_ctrl, 543 }; 544 545 static int nvme_loop_create_io_queues(struct nvme_loop_ctrl *ctrl) 546 { 547 int ret; 548 549 ret = nvme_loop_init_io_queues(ctrl); 550 if (ret) 551 return ret; 552 553 memset(&ctrl->tag_set, 0, sizeof(ctrl->tag_set)); 554 ctrl->tag_set.ops = &nvme_loop_mq_ops; 555 ctrl->tag_set.queue_depth = ctrl->ctrl.opts->queue_size; 556 ctrl->tag_set.reserved_tags = 1; /* fabric connect */ 557 ctrl->tag_set.numa_node = NUMA_NO_NODE; 558 ctrl->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 559 ctrl->tag_set.cmd_size = sizeof(struct nvme_loop_iod) + 560 SG_CHUNK_SIZE * sizeof(struct scatterlist); 561 ctrl->tag_set.driver_data = ctrl; 562 ctrl->tag_set.nr_hw_queues = ctrl->queue_count - 1; 563 ctrl->tag_set.timeout = NVME_IO_TIMEOUT; 564 ctrl->ctrl.tagset = &ctrl->tag_set; 565 566 ret = blk_mq_alloc_tag_set(&ctrl->tag_set); 567 if (ret) 568 goto out_destroy_queues; 569 570 ctrl->ctrl.connect_q = blk_mq_init_queue(&ctrl->tag_set); 571 if (IS_ERR(ctrl->ctrl.connect_q)) { 572 ret = PTR_ERR(ctrl->ctrl.connect_q); 573 goto out_free_tagset; 574 } 575 576 ret = nvme_loop_connect_io_queues(ctrl); 577 if (ret) 578 goto out_cleanup_connect_q; 579 580 return 0; 581 582 out_cleanup_connect_q: 583 blk_cleanup_queue(ctrl->ctrl.connect_q); 584 out_free_tagset: 585 blk_mq_free_tag_set(&ctrl->tag_set); 586 out_destroy_queues: 587 nvme_loop_destroy_io_queues(ctrl); 588 return ret; 589 } 590 591 static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev, 592 struct nvmf_ctrl_options *opts) 593 { 594 struct nvme_loop_ctrl *ctrl; 595 bool changed; 596 int ret; 597 598 ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL); 599 if (!ctrl) 600 return ERR_PTR(-ENOMEM); 601 ctrl->ctrl.opts = opts; 602 INIT_LIST_HEAD(&ctrl->list); 603 604 INIT_WORK(&ctrl->delete_work, nvme_loop_del_ctrl_work); 605 INIT_WORK(&ctrl->ctrl.reset_work, nvme_loop_reset_ctrl_work); 606 607 ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_loop_ctrl_ops, 608 0 /* no quirks, we're perfect! */); 609 if (ret) 610 goto out_put_ctrl; 611 612 ret = -ENOMEM; 613 614 ctrl->ctrl.sqsize = opts->queue_size - 1; 615 ctrl->ctrl.kato = opts->kato; 616 617 ctrl->queues = kcalloc(opts->nr_io_queues + 1, sizeof(*ctrl->queues), 618 GFP_KERNEL); 619 if (!ctrl->queues) 620 goto out_uninit_ctrl; 621 622 ret = nvme_loop_configure_admin_queue(ctrl); 623 if (ret) 624 goto out_free_queues; 625 626 if (opts->queue_size > ctrl->ctrl.maxcmd) { 627 /* warn if maxcmd is lower than queue_size */ 628 dev_warn(ctrl->ctrl.device, 629 "queue_size %zu > ctrl maxcmd %u, clamping down\n", 630 opts->queue_size, ctrl->ctrl.maxcmd); 631 opts->queue_size = ctrl->ctrl.maxcmd; 632 } 633 634 if (opts->nr_io_queues) { 635 ret = nvme_loop_create_io_queues(ctrl); 636 if (ret) 637 goto out_remove_admin_queue; 638 } 639 640 nvme_loop_init_iod(ctrl, &ctrl->async_event_iod, 0); 641 642 dev_info(ctrl->ctrl.device, 643 "new ctrl: \"%s\"\n", ctrl->ctrl.opts->subsysnqn); 644 645 kref_get(&ctrl->ctrl.kref); 646 647 changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE); 648 WARN_ON_ONCE(!changed); 649 650 mutex_lock(&nvme_loop_ctrl_mutex); 651 list_add_tail(&ctrl->list, &nvme_loop_ctrl_list); 652 mutex_unlock(&nvme_loop_ctrl_mutex); 653 654 if (opts->nr_io_queues) { 655 nvme_queue_scan(&ctrl->ctrl); 656 nvme_queue_async_events(&ctrl->ctrl); 657 } 658 659 return &ctrl->ctrl; 660 661 out_remove_admin_queue: 662 nvme_loop_destroy_admin_queue(ctrl); 663 out_free_queues: 664 kfree(ctrl->queues); 665 out_uninit_ctrl: 666 nvme_uninit_ctrl(&ctrl->ctrl); 667 out_put_ctrl: 668 nvme_put_ctrl(&ctrl->ctrl); 669 if (ret > 0) 670 ret = -EIO; 671 return ERR_PTR(ret); 672 } 673 674 static int nvme_loop_add_port(struct nvmet_port *port) 675 { 676 /* 677 * XXX: disalow adding more than one port so 678 * there is no connection rejections when a 679 * a subsystem is assigned to a port for which 680 * loop doesn't have a pointer. 681 * This scenario would be possible if we allowed 682 * more than one port to be added and a subsystem 683 * was assigned to a port other than nvmet_loop_port. 684 */ 685 686 if (nvmet_loop_port) 687 return -EPERM; 688 689 nvmet_loop_port = port; 690 return 0; 691 } 692 693 static void nvme_loop_remove_port(struct nvmet_port *port) 694 { 695 if (port == nvmet_loop_port) 696 nvmet_loop_port = NULL; 697 } 698 699 static struct nvmet_fabrics_ops nvme_loop_ops = { 700 .owner = THIS_MODULE, 701 .type = NVMF_TRTYPE_LOOP, 702 .add_port = nvme_loop_add_port, 703 .remove_port = nvme_loop_remove_port, 704 .queue_response = nvme_loop_queue_response, 705 .delete_ctrl = nvme_loop_delete_ctrl, 706 }; 707 708 static struct nvmf_transport_ops nvme_loop_transport = { 709 .name = "loop", 710 .create_ctrl = nvme_loop_create_ctrl, 711 }; 712 713 static int __init nvme_loop_init_module(void) 714 { 715 int ret; 716 717 ret = nvmet_register_transport(&nvme_loop_ops); 718 if (ret) 719 return ret; 720 721 ret = nvmf_register_transport(&nvme_loop_transport); 722 if (ret) 723 nvmet_unregister_transport(&nvme_loop_ops); 724 725 return ret; 726 } 727 728 static void __exit nvme_loop_cleanup_module(void) 729 { 730 struct nvme_loop_ctrl *ctrl, *next; 731 732 nvmf_unregister_transport(&nvme_loop_transport); 733 nvmet_unregister_transport(&nvme_loop_ops); 734 735 mutex_lock(&nvme_loop_ctrl_mutex); 736 list_for_each_entry_safe(ctrl, next, &nvme_loop_ctrl_list, list) 737 __nvme_loop_del_ctrl(ctrl); 738 mutex_unlock(&nvme_loop_ctrl_mutex); 739 740 flush_workqueue(nvme_wq); 741 } 742 743 module_init(nvme_loop_init_module); 744 module_exit(nvme_loop_cleanup_module); 745 746 MODULE_LICENSE("GPL v2"); 747 MODULE_ALIAS("nvmet-transport-254"); /* 254 == NVMF_TRTYPE_LOOP */ 748