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