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_AQ_DEPTH 256 25 26 #define NVME_LOOP_MAX_SEGMENTS 256 27 28 /* 29 * We handle AEN commands ourselves and don't even let the 30 * block layer know about them. 31 */ 32 #define NVME_LOOP_NR_AEN_COMMANDS 1 33 #define NVME_LOOP_AQ_BLKMQ_DEPTH \ 34 (NVME_LOOP_AQ_DEPTH - NVME_LOOP_NR_AEN_COMMANDS) 35 36 struct nvme_loop_iod { 37 struct nvme_request nvme_req; 38 struct nvme_command cmd; 39 struct nvme_completion rsp; 40 struct nvmet_req req; 41 struct nvme_loop_queue *queue; 42 struct work_struct work; 43 struct sg_table sg_table; 44 struct scatterlist first_sgl[]; 45 }; 46 47 struct nvme_loop_ctrl { 48 spinlock_t lock; 49 struct nvme_loop_queue *queues; 50 u32 queue_count; 51 52 struct blk_mq_tag_set admin_tag_set; 53 54 struct list_head list; 55 u64 cap; 56 struct blk_mq_tag_set tag_set; 57 struct nvme_loop_iod async_event_iod; 58 struct nvme_ctrl ctrl; 59 60 struct nvmet_ctrl *target_ctrl; 61 struct work_struct delete_work; 62 struct work_struct reset_work; 63 }; 64 65 static inline struct nvme_loop_ctrl *to_loop_ctrl(struct nvme_ctrl *ctrl) 66 { 67 return container_of(ctrl, struct nvme_loop_ctrl, ctrl); 68 } 69 70 struct nvme_loop_queue { 71 struct nvmet_cq nvme_cq; 72 struct nvmet_sq nvme_sq; 73 struct nvme_loop_ctrl *ctrl; 74 }; 75 76 static struct nvmet_port *nvmet_loop_port; 77 78 static LIST_HEAD(nvme_loop_ctrl_list); 79 static DEFINE_MUTEX(nvme_loop_ctrl_mutex); 80 81 static void nvme_loop_queue_response(struct nvmet_req *nvme_req); 82 static void nvme_loop_delete_ctrl(struct nvmet_ctrl *ctrl); 83 84 static struct nvmet_fabrics_ops nvme_loop_ops; 85 86 static inline int nvme_loop_queue_idx(struct nvme_loop_queue *queue) 87 { 88 return queue - queue->ctrl->queues; 89 } 90 91 static void nvme_loop_complete_rq(struct request *req) 92 { 93 struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req); 94 95 nvme_cleanup_cmd(req); 96 sg_free_table_chained(&iod->sg_table, true); 97 nvme_complete_rq(req); 98 } 99 100 static struct blk_mq_tags *nvme_loop_tagset(struct nvme_loop_queue *queue) 101 { 102 u32 queue_idx = nvme_loop_queue_idx(queue); 103 104 if (queue_idx == 0) 105 return queue->ctrl->admin_tag_set.tags[queue_idx]; 106 return queue->ctrl->tag_set.tags[queue_idx - 1]; 107 } 108 109 static void nvme_loop_queue_response(struct nvmet_req *req) 110 { 111 struct nvme_loop_queue *queue = 112 container_of(req->sq, struct nvme_loop_queue, nvme_sq); 113 struct nvme_completion *cqe = req->rsp; 114 115 /* 116 * AEN requests are special as they don't time out and can 117 * survive any kind of queue freeze and often don't respond to 118 * aborts. We don't even bother to allocate a struct request 119 * for them but rather special case them here. 120 */ 121 if (unlikely(nvme_loop_queue_idx(queue) == 0 && 122 cqe->command_id >= NVME_LOOP_AQ_BLKMQ_DEPTH)) { 123 nvme_complete_async_event(&queue->ctrl->ctrl, cqe->status, 124 &cqe->result); 125 } else { 126 struct request *rq; 127 128 rq = blk_mq_tag_to_rq(nvme_loop_tagset(queue), cqe->command_id); 129 if (!rq) { 130 dev_err(queue->ctrl->ctrl.device, 131 "tag 0x%x on queue %d not found\n", 132 cqe->command_id, nvme_loop_queue_idx(queue)); 133 return; 134 } 135 136 nvme_end_request(rq, cqe->status, cqe->result); 137 } 138 } 139 140 static void nvme_loop_execute_work(struct work_struct *work) 141 { 142 struct nvme_loop_iod *iod = 143 container_of(work, struct nvme_loop_iod, work); 144 145 iod->req.execute(&iod->req); 146 } 147 148 static enum blk_eh_timer_return 149 nvme_loop_timeout(struct request *rq, bool reserved) 150 { 151 struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(rq); 152 153 /* queue error recovery */ 154 schedule_work(&iod->queue->ctrl->reset_work); 155 156 /* fail with DNR on admin cmd timeout */ 157 nvme_req(rq)->status = NVME_SC_ABORT_REQ | NVME_SC_DNR; 158 159 return BLK_EH_HANDLED; 160 } 161 162 static int nvme_loop_queue_rq(struct blk_mq_hw_ctx *hctx, 163 const struct blk_mq_queue_data *bd) 164 { 165 struct nvme_ns *ns = hctx->queue->queuedata; 166 struct nvme_loop_queue *queue = hctx->driver_data; 167 struct request *req = bd->rq; 168 struct nvme_loop_iod *iod = blk_mq_rq_to_pdu(req); 169 int ret; 170 171 ret = nvme_setup_cmd(ns, req, &iod->cmd); 172 if (ret != BLK_MQ_RQ_QUEUE_OK) 173 return ret; 174 175 iod->cmd.common.flags |= NVME_CMD_SGL_METABUF; 176 iod->req.port = nvmet_loop_port; 177 if (!nvmet_req_init(&iod->req, &queue->nvme_cq, 178 &queue->nvme_sq, &nvme_loop_ops)) { 179 nvme_cleanup_cmd(req); 180 blk_mq_start_request(req); 181 nvme_loop_queue_response(&iod->req); 182 return BLK_MQ_RQ_QUEUE_OK; 183 } 184 185 if (blk_rq_bytes(req)) { 186 iod->sg_table.sgl = iod->first_sgl; 187 ret = sg_alloc_table_chained(&iod->sg_table, 188 blk_rq_nr_phys_segments(req), 189 iod->sg_table.sgl); 190 if (ret) 191 return BLK_MQ_RQ_QUEUE_BUSY; 192 193 iod->req.sg = iod->sg_table.sgl; 194 iod->req.sg_cnt = blk_rq_map_sg(req->q, req, iod->sg_table.sgl); 195 } 196 197 blk_mq_start_request(req); 198 199 schedule_work(&iod->work); 200 return BLK_MQ_RQ_QUEUE_OK; 201 } 202 203 static void nvme_loop_submit_async_event(struct nvme_ctrl *arg, int aer_idx) 204 { 205 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(arg); 206 struct nvme_loop_queue *queue = &ctrl->queues[0]; 207 struct nvme_loop_iod *iod = &ctrl->async_event_iod; 208 209 memset(&iod->cmd, 0, sizeof(iod->cmd)); 210 iod->cmd.common.opcode = nvme_admin_async_event; 211 iod->cmd.common.command_id = NVME_LOOP_AQ_BLKMQ_DEPTH; 212 iod->cmd.common.flags |= NVME_CMD_SGL_METABUF; 213 214 if (!nvmet_req_init(&iod->req, &queue->nvme_cq, &queue->nvme_sq, 215 &nvme_loop_ops)) { 216 dev_err(ctrl->ctrl.device, "failed async event work\n"); 217 return; 218 } 219 220 schedule_work(&iod->work); 221 } 222 223 static int nvme_loop_init_iod(struct nvme_loop_ctrl *ctrl, 224 struct nvme_loop_iod *iod, unsigned int queue_idx) 225 { 226 iod->req.cmd = &iod->cmd; 227 iod->req.rsp = &iod->rsp; 228 iod->queue = &ctrl->queues[queue_idx]; 229 INIT_WORK(&iod->work, nvme_loop_execute_work); 230 return 0; 231 } 232 233 static int nvme_loop_init_request(struct blk_mq_tag_set *set, 234 struct request *req, unsigned int hctx_idx, 235 unsigned int numa_node) 236 { 237 return nvme_loop_init_iod(set->driver_data, blk_mq_rq_to_pdu(req), 238 hctx_idx + 1); 239 } 240 241 static int nvme_loop_init_admin_request(struct blk_mq_tag_set *set, 242 struct request *req, unsigned int hctx_idx, 243 unsigned int numa_node) 244 { 245 return nvme_loop_init_iod(set->driver_data, blk_mq_rq_to_pdu(req), 0); 246 } 247 248 static int nvme_loop_init_hctx(struct blk_mq_hw_ctx *hctx, void *data, 249 unsigned int hctx_idx) 250 { 251 struct nvme_loop_ctrl *ctrl = data; 252 struct nvme_loop_queue *queue = &ctrl->queues[hctx_idx + 1]; 253 254 BUG_ON(hctx_idx >= ctrl->queue_count); 255 256 hctx->driver_data = queue; 257 return 0; 258 } 259 260 static int nvme_loop_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data, 261 unsigned int hctx_idx) 262 { 263 struct nvme_loop_ctrl *ctrl = data; 264 struct nvme_loop_queue *queue = &ctrl->queues[0]; 265 266 BUG_ON(hctx_idx != 0); 267 268 hctx->driver_data = queue; 269 return 0; 270 } 271 272 static const struct blk_mq_ops nvme_loop_mq_ops = { 273 .queue_rq = nvme_loop_queue_rq, 274 .complete = nvme_loop_complete_rq, 275 .init_request = nvme_loop_init_request, 276 .init_hctx = nvme_loop_init_hctx, 277 .timeout = nvme_loop_timeout, 278 }; 279 280 static const struct blk_mq_ops nvme_loop_admin_mq_ops = { 281 .queue_rq = nvme_loop_queue_rq, 282 .complete = nvme_loop_complete_rq, 283 .init_request = nvme_loop_init_admin_request, 284 .init_hctx = nvme_loop_init_admin_hctx, 285 .timeout = nvme_loop_timeout, 286 }; 287 288 static void nvme_loop_destroy_admin_queue(struct nvme_loop_ctrl *ctrl) 289 { 290 nvmet_sq_destroy(&ctrl->queues[0].nvme_sq); 291 blk_cleanup_queue(ctrl->ctrl.admin_q); 292 blk_mq_free_tag_set(&ctrl->admin_tag_set); 293 } 294 295 static void nvme_loop_free_ctrl(struct nvme_ctrl *nctrl) 296 { 297 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl); 298 299 if (list_empty(&ctrl->list)) 300 goto free_ctrl; 301 302 mutex_lock(&nvme_loop_ctrl_mutex); 303 list_del(&ctrl->list); 304 mutex_unlock(&nvme_loop_ctrl_mutex); 305 306 if (nctrl->tagset) { 307 blk_cleanup_queue(ctrl->ctrl.connect_q); 308 blk_mq_free_tag_set(&ctrl->tag_set); 309 } 310 kfree(ctrl->queues); 311 nvmf_free_options(nctrl->opts); 312 free_ctrl: 313 kfree(ctrl); 314 } 315 316 static void nvme_loop_destroy_io_queues(struct nvme_loop_ctrl *ctrl) 317 { 318 int i; 319 320 for (i = 1; i < ctrl->queue_count; i++) 321 nvmet_sq_destroy(&ctrl->queues[i].nvme_sq); 322 } 323 324 static int nvme_loop_init_io_queues(struct nvme_loop_ctrl *ctrl) 325 { 326 struct nvmf_ctrl_options *opts = ctrl->ctrl.opts; 327 unsigned int nr_io_queues; 328 int ret, i; 329 330 nr_io_queues = min(opts->nr_io_queues, num_online_cpus()); 331 ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues); 332 if (ret || !nr_io_queues) 333 return ret; 334 335 dev_info(ctrl->ctrl.device, "creating %d I/O queues.\n", nr_io_queues); 336 337 for (i = 1; i <= nr_io_queues; i++) { 338 ctrl->queues[i].ctrl = ctrl; 339 ret = nvmet_sq_init(&ctrl->queues[i].nvme_sq); 340 if (ret) 341 goto out_destroy_queues; 342 343 ctrl->queue_count++; 344 } 345 346 return 0; 347 348 out_destroy_queues: 349 nvme_loop_destroy_io_queues(ctrl); 350 return ret; 351 } 352 353 static int nvme_loop_connect_io_queues(struct nvme_loop_ctrl *ctrl) 354 { 355 int i, ret; 356 357 for (i = 1; i < ctrl->queue_count; i++) { 358 ret = nvmf_connect_io_queue(&ctrl->ctrl, i); 359 if (ret) 360 return ret; 361 } 362 363 return 0; 364 } 365 366 static int nvme_loop_configure_admin_queue(struct nvme_loop_ctrl *ctrl) 367 { 368 int error; 369 370 memset(&ctrl->admin_tag_set, 0, sizeof(ctrl->admin_tag_set)); 371 ctrl->admin_tag_set.ops = &nvme_loop_admin_mq_ops; 372 ctrl->admin_tag_set.queue_depth = NVME_LOOP_AQ_BLKMQ_DEPTH; 373 ctrl->admin_tag_set.reserved_tags = 2; /* connect + keep-alive */ 374 ctrl->admin_tag_set.numa_node = NUMA_NO_NODE; 375 ctrl->admin_tag_set.cmd_size = sizeof(struct nvme_loop_iod) + 376 SG_CHUNK_SIZE * sizeof(struct scatterlist); 377 ctrl->admin_tag_set.driver_data = ctrl; 378 ctrl->admin_tag_set.nr_hw_queues = 1; 379 ctrl->admin_tag_set.timeout = ADMIN_TIMEOUT; 380 381 ctrl->queues[0].ctrl = ctrl; 382 error = nvmet_sq_init(&ctrl->queues[0].nvme_sq); 383 if (error) 384 return error; 385 ctrl->queue_count = 1; 386 387 error = blk_mq_alloc_tag_set(&ctrl->admin_tag_set); 388 if (error) 389 goto out_free_sq; 390 391 ctrl->ctrl.admin_q = blk_mq_init_queue(&ctrl->admin_tag_set); 392 if (IS_ERR(ctrl->ctrl.admin_q)) { 393 error = PTR_ERR(ctrl->ctrl.admin_q); 394 goto out_free_tagset; 395 } 396 397 error = nvmf_connect_admin_queue(&ctrl->ctrl); 398 if (error) 399 goto out_cleanup_queue; 400 401 error = nvmf_reg_read64(&ctrl->ctrl, NVME_REG_CAP, &ctrl->cap); 402 if (error) { 403 dev_err(ctrl->ctrl.device, 404 "prop_get NVME_REG_CAP failed\n"); 405 goto out_cleanup_queue; 406 } 407 408 ctrl->ctrl.sqsize = 409 min_t(int, NVME_CAP_MQES(ctrl->cap), ctrl->ctrl.sqsize); 410 411 error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->cap); 412 if (error) 413 goto out_cleanup_queue; 414 415 ctrl->ctrl.max_hw_sectors = 416 (NVME_LOOP_MAX_SEGMENTS - 1) << (PAGE_SHIFT - 9); 417 418 error = nvme_init_identify(&ctrl->ctrl); 419 if (error) 420 goto out_cleanup_queue; 421 422 nvme_start_keep_alive(&ctrl->ctrl); 423 424 return 0; 425 426 out_cleanup_queue: 427 blk_cleanup_queue(ctrl->ctrl.admin_q); 428 out_free_tagset: 429 blk_mq_free_tag_set(&ctrl->admin_tag_set); 430 out_free_sq: 431 nvmet_sq_destroy(&ctrl->queues[0].nvme_sq); 432 return error; 433 } 434 435 static void nvme_loop_shutdown_ctrl(struct nvme_loop_ctrl *ctrl) 436 { 437 nvme_stop_keep_alive(&ctrl->ctrl); 438 439 if (ctrl->queue_count > 1) { 440 nvme_stop_queues(&ctrl->ctrl); 441 blk_mq_tagset_busy_iter(&ctrl->tag_set, 442 nvme_cancel_request, &ctrl->ctrl); 443 nvme_loop_destroy_io_queues(ctrl); 444 } 445 446 if (ctrl->ctrl.state == NVME_CTRL_LIVE) 447 nvme_shutdown_ctrl(&ctrl->ctrl); 448 449 blk_mq_stop_hw_queues(ctrl->ctrl.admin_q); 450 blk_mq_tagset_busy_iter(&ctrl->admin_tag_set, 451 nvme_cancel_request, &ctrl->ctrl); 452 nvme_loop_destroy_admin_queue(ctrl); 453 } 454 455 static void nvme_loop_del_ctrl_work(struct work_struct *work) 456 { 457 struct nvme_loop_ctrl *ctrl = container_of(work, 458 struct nvme_loop_ctrl, delete_work); 459 460 nvme_uninit_ctrl(&ctrl->ctrl); 461 nvme_loop_shutdown_ctrl(ctrl); 462 nvme_put_ctrl(&ctrl->ctrl); 463 } 464 465 static int __nvme_loop_del_ctrl(struct nvme_loop_ctrl *ctrl) 466 { 467 if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_DELETING)) 468 return -EBUSY; 469 470 if (!schedule_work(&ctrl->delete_work)) 471 return -EBUSY; 472 473 return 0; 474 } 475 476 static int nvme_loop_del_ctrl(struct nvme_ctrl *nctrl) 477 { 478 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl); 479 int ret; 480 481 ret = __nvme_loop_del_ctrl(ctrl); 482 if (ret) 483 return ret; 484 485 flush_work(&ctrl->delete_work); 486 487 return 0; 488 } 489 490 static void nvme_loop_delete_ctrl(struct nvmet_ctrl *nctrl) 491 { 492 struct nvme_loop_ctrl *ctrl; 493 494 mutex_lock(&nvme_loop_ctrl_mutex); 495 list_for_each_entry(ctrl, &nvme_loop_ctrl_list, list) { 496 if (ctrl->ctrl.cntlid == nctrl->cntlid) 497 __nvme_loop_del_ctrl(ctrl); 498 } 499 mutex_unlock(&nvme_loop_ctrl_mutex); 500 } 501 502 static void nvme_loop_reset_ctrl_work(struct work_struct *work) 503 { 504 struct nvme_loop_ctrl *ctrl = container_of(work, 505 struct nvme_loop_ctrl, reset_work); 506 bool changed; 507 int ret; 508 509 nvme_loop_shutdown_ctrl(ctrl); 510 511 ret = nvme_loop_configure_admin_queue(ctrl); 512 if (ret) 513 goto out_disable; 514 515 ret = nvme_loop_init_io_queues(ctrl); 516 if (ret) 517 goto out_destroy_admin; 518 519 ret = nvme_loop_connect_io_queues(ctrl); 520 if (ret) 521 goto out_destroy_io; 522 523 changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE); 524 WARN_ON_ONCE(!changed); 525 526 nvme_queue_scan(&ctrl->ctrl); 527 nvme_queue_async_events(&ctrl->ctrl); 528 529 nvme_start_queues(&ctrl->ctrl); 530 531 return; 532 533 out_destroy_io: 534 nvme_loop_destroy_io_queues(ctrl); 535 out_destroy_admin: 536 nvme_loop_destroy_admin_queue(ctrl); 537 out_disable: 538 dev_warn(ctrl->ctrl.device, "Removing after reset failure\n"); 539 nvme_uninit_ctrl(&ctrl->ctrl); 540 nvme_put_ctrl(&ctrl->ctrl); 541 } 542 543 static int nvme_loop_reset_ctrl(struct nvme_ctrl *nctrl) 544 { 545 struct nvme_loop_ctrl *ctrl = to_loop_ctrl(nctrl); 546 547 if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_RESETTING)) 548 return -EBUSY; 549 550 if (!schedule_work(&ctrl->reset_work)) 551 return -EBUSY; 552 553 flush_work(&ctrl->reset_work); 554 555 return 0; 556 } 557 558 static const struct nvme_ctrl_ops nvme_loop_ctrl_ops = { 559 .name = "loop", 560 .module = THIS_MODULE, 561 .flags = NVME_F_FABRICS, 562 .reg_read32 = nvmf_reg_read32, 563 .reg_read64 = nvmf_reg_read64, 564 .reg_write32 = nvmf_reg_write32, 565 .reset_ctrl = nvme_loop_reset_ctrl, 566 .free_ctrl = nvme_loop_free_ctrl, 567 .submit_async_event = nvme_loop_submit_async_event, 568 .delete_ctrl = nvme_loop_del_ctrl, 569 .get_subsysnqn = nvmf_get_subsysnqn, 570 }; 571 572 static int nvme_loop_create_io_queues(struct nvme_loop_ctrl *ctrl) 573 { 574 int ret; 575 576 ret = nvme_loop_init_io_queues(ctrl); 577 if (ret) 578 return ret; 579 580 memset(&ctrl->tag_set, 0, sizeof(ctrl->tag_set)); 581 ctrl->tag_set.ops = &nvme_loop_mq_ops; 582 ctrl->tag_set.queue_depth = ctrl->ctrl.opts->queue_size; 583 ctrl->tag_set.reserved_tags = 1; /* fabric connect */ 584 ctrl->tag_set.numa_node = NUMA_NO_NODE; 585 ctrl->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 586 ctrl->tag_set.cmd_size = sizeof(struct nvme_loop_iod) + 587 SG_CHUNK_SIZE * sizeof(struct scatterlist); 588 ctrl->tag_set.driver_data = ctrl; 589 ctrl->tag_set.nr_hw_queues = ctrl->queue_count - 1; 590 ctrl->tag_set.timeout = NVME_IO_TIMEOUT; 591 ctrl->ctrl.tagset = &ctrl->tag_set; 592 593 ret = blk_mq_alloc_tag_set(&ctrl->tag_set); 594 if (ret) 595 goto out_destroy_queues; 596 597 ctrl->ctrl.connect_q = blk_mq_init_queue(&ctrl->tag_set); 598 if (IS_ERR(ctrl->ctrl.connect_q)) { 599 ret = PTR_ERR(ctrl->ctrl.connect_q); 600 goto out_free_tagset; 601 } 602 603 ret = nvme_loop_connect_io_queues(ctrl); 604 if (ret) 605 goto out_cleanup_connect_q; 606 607 return 0; 608 609 out_cleanup_connect_q: 610 blk_cleanup_queue(ctrl->ctrl.connect_q); 611 out_free_tagset: 612 blk_mq_free_tag_set(&ctrl->tag_set); 613 out_destroy_queues: 614 nvme_loop_destroy_io_queues(ctrl); 615 return ret; 616 } 617 618 static struct nvme_ctrl *nvme_loop_create_ctrl(struct device *dev, 619 struct nvmf_ctrl_options *opts) 620 { 621 struct nvme_loop_ctrl *ctrl; 622 bool changed; 623 int ret; 624 625 ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL); 626 if (!ctrl) 627 return ERR_PTR(-ENOMEM); 628 ctrl->ctrl.opts = opts; 629 INIT_LIST_HEAD(&ctrl->list); 630 631 INIT_WORK(&ctrl->delete_work, nvme_loop_del_ctrl_work); 632 INIT_WORK(&ctrl->reset_work, nvme_loop_reset_ctrl_work); 633 634 ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_loop_ctrl_ops, 635 0 /* no quirks, we're perfect! */); 636 if (ret) 637 goto out_put_ctrl; 638 639 spin_lock_init(&ctrl->lock); 640 641 ret = -ENOMEM; 642 643 ctrl->ctrl.sqsize = opts->queue_size - 1; 644 ctrl->ctrl.kato = opts->kato; 645 646 ctrl->queues = kcalloc(opts->nr_io_queues + 1, sizeof(*ctrl->queues), 647 GFP_KERNEL); 648 if (!ctrl->queues) 649 goto out_uninit_ctrl; 650 651 ret = nvme_loop_configure_admin_queue(ctrl); 652 if (ret) 653 goto out_free_queues; 654 655 if (opts->queue_size > ctrl->ctrl.maxcmd) { 656 /* warn if maxcmd is lower than queue_size */ 657 dev_warn(ctrl->ctrl.device, 658 "queue_size %zu > ctrl maxcmd %u, clamping down\n", 659 opts->queue_size, ctrl->ctrl.maxcmd); 660 opts->queue_size = ctrl->ctrl.maxcmd; 661 } 662 663 if (opts->nr_io_queues) { 664 ret = nvme_loop_create_io_queues(ctrl); 665 if (ret) 666 goto out_remove_admin_queue; 667 } 668 669 nvme_loop_init_iod(ctrl, &ctrl->async_event_iod, 0); 670 671 dev_info(ctrl->ctrl.device, 672 "new ctrl: \"%s\"\n", ctrl->ctrl.opts->subsysnqn); 673 674 kref_get(&ctrl->ctrl.kref); 675 676 changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE); 677 WARN_ON_ONCE(!changed); 678 679 mutex_lock(&nvme_loop_ctrl_mutex); 680 list_add_tail(&ctrl->list, &nvme_loop_ctrl_list); 681 mutex_unlock(&nvme_loop_ctrl_mutex); 682 683 if (opts->nr_io_queues) { 684 nvme_queue_scan(&ctrl->ctrl); 685 nvme_queue_async_events(&ctrl->ctrl); 686 } 687 688 return &ctrl->ctrl; 689 690 out_remove_admin_queue: 691 nvme_loop_destroy_admin_queue(ctrl); 692 out_free_queues: 693 kfree(ctrl->queues); 694 out_uninit_ctrl: 695 nvme_uninit_ctrl(&ctrl->ctrl); 696 out_put_ctrl: 697 nvme_put_ctrl(&ctrl->ctrl); 698 if (ret > 0) 699 ret = -EIO; 700 return ERR_PTR(ret); 701 } 702 703 static int nvme_loop_add_port(struct nvmet_port *port) 704 { 705 /* 706 * XXX: disalow adding more than one port so 707 * there is no connection rejections when a 708 * a subsystem is assigned to a port for which 709 * loop doesn't have a pointer. 710 * This scenario would be possible if we allowed 711 * more than one port to be added and a subsystem 712 * was assigned to a port other than nvmet_loop_port. 713 */ 714 715 if (nvmet_loop_port) 716 return -EPERM; 717 718 nvmet_loop_port = port; 719 return 0; 720 } 721 722 static void nvme_loop_remove_port(struct nvmet_port *port) 723 { 724 if (port == nvmet_loop_port) 725 nvmet_loop_port = NULL; 726 } 727 728 static struct nvmet_fabrics_ops nvme_loop_ops = { 729 .owner = THIS_MODULE, 730 .type = NVMF_TRTYPE_LOOP, 731 .add_port = nvme_loop_add_port, 732 .remove_port = nvme_loop_remove_port, 733 .queue_response = nvme_loop_queue_response, 734 .delete_ctrl = nvme_loop_delete_ctrl, 735 }; 736 737 static struct nvmf_transport_ops nvme_loop_transport = { 738 .name = "loop", 739 .create_ctrl = nvme_loop_create_ctrl, 740 }; 741 742 static int __init nvme_loop_init_module(void) 743 { 744 int ret; 745 746 ret = nvmet_register_transport(&nvme_loop_ops); 747 if (ret) 748 return ret; 749 750 ret = nvmf_register_transport(&nvme_loop_transport); 751 if (ret) 752 nvmet_unregister_transport(&nvme_loop_ops); 753 754 return ret; 755 } 756 757 static void __exit nvme_loop_cleanup_module(void) 758 { 759 struct nvme_loop_ctrl *ctrl, *next; 760 761 nvmf_unregister_transport(&nvme_loop_transport); 762 nvmet_unregister_transport(&nvme_loop_ops); 763 764 mutex_lock(&nvme_loop_ctrl_mutex); 765 list_for_each_entry_safe(ctrl, next, &nvme_loop_ctrl_list, list) 766 __nvme_loop_del_ctrl(ctrl); 767 mutex_unlock(&nvme_loop_ctrl_mutex); 768 769 flush_scheduled_work(); 770 } 771 772 module_init(nvme_loop_init_module); 773 module_exit(nvme_loop_cleanup_module); 774 775 MODULE_LICENSE("GPL v2"); 776 MODULE_ALIAS("nvmet-transport-254"); /* 254 == NVMF_TRTYPE_LOOP */ 777