xref: /openbmc/linux/drivers/nvme/host/rdma.c (revision 98ddec80)
1 /*
2  * NVMe over Fabrics RDMA host code.
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/module.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <rdma/mr_pool.h>
19 #include <linux/err.h>
20 #include <linux/string.h>
21 #include <linux/atomic.h>
22 #include <linux/blk-mq.h>
23 #include <linux/blk-mq-rdma.h>
24 #include <linux/types.h>
25 #include <linux/list.h>
26 #include <linux/mutex.h>
27 #include <linux/scatterlist.h>
28 #include <linux/nvme.h>
29 #include <asm/unaligned.h>
30 
31 #include <rdma/ib_verbs.h>
32 #include <rdma/rdma_cm.h>
33 #include <linux/nvme-rdma.h>
34 
35 #include "nvme.h"
36 #include "fabrics.h"
37 
38 
39 #define NVME_RDMA_CONNECT_TIMEOUT_MS	3000		/* 3 second */
40 
41 #define NVME_RDMA_MAX_SEGMENTS		256
42 
43 #define NVME_RDMA_MAX_INLINE_SEGMENTS	1
44 
45 struct nvme_rdma_device {
46 	struct ib_device	*dev;
47 	struct ib_pd		*pd;
48 	struct kref		ref;
49 	struct list_head	entry;
50 };
51 
52 struct nvme_rdma_qe {
53 	struct ib_cqe		cqe;
54 	void			*data;
55 	u64			dma;
56 };
57 
58 struct nvme_rdma_queue;
59 struct nvme_rdma_request {
60 	struct nvme_request	req;
61 	struct ib_mr		*mr;
62 	struct nvme_rdma_qe	sqe;
63 	union nvme_result	result;
64 	__le16			status;
65 	refcount_t		ref;
66 	struct ib_sge		sge[1 + NVME_RDMA_MAX_INLINE_SEGMENTS];
67 	u32			num_sge;
68 	int			nents;
69 	struct ib_reg_wr	reg_wr;
70 	struct ib_cqe		reg_cqe;
71 	struct nvme_rdma_queue  *queue;
72 	struct sg_table		sg_table;
73 	struct scatterlist	first_sgl[];
74 };
75 
76 enum nvme_rdma_queue_flags {
77 	NVME_RDMA_Q_ALLOCATED		= 0,
78 	NVME_RDMA_Q_LIVE		= 1,
79 	NVME_RDMA_Q_TR_READY		= 2,
80 };
81 
82 struct nvme_rdma_queue {
83 	struct nvme_rdma_qe	*rsp_ring;
84 	int			queue_size;
85 	size_t			cmnd_capsule_len;
86 	struct nvme_rdma_ctrl	*ctrl;
87 	struct nvme_rdma_device	*device;
88 	struct ib_cq		*ib_cq;
89 	struct ib_qp		*qp;
90 
91 	unsigned long		flags;
92 	struct rdma_cm_id	*cm_id;
93 	int			cm_error;
94 	struct completion	cm_done;
95 };
96 
97 struct nvme_rdma_ctrl {
98 	/* read only in the hot path */
99 	struct nvme_rdma_queue	*queues;
100 
101 	/* other member variables */
102 	struct blk_mq_tag_set	tag_set;
103 	struct work_struct	err_work;
104 
105 	struct nvme_rdma_qe	async_event_sqe;
106 
107 	struct delayed_work	reconnect_work;
108 
109 	struct list_head	list;
110 
111 	struct blk_mq_tag_set	admin_tag_set;
112 	struct nvme_rdma_device	*device;
113 
114 	u32			max_fr_pages;
115 
116 	struct sockaddr_storage addr;
117 	struct sockaddr_storage src_addr;
118 
119 	struct nvme_ctrl	ctrl;
120 };
121 
122 static inline struct nvme_rdma_ctrl *to_rdma_ctrl(struct nvme_ctrl *ctrl)
123 {
124 	return container_of(ctrl, struct nvme_rdma_ctrl, ctrl);
125 }
126 
127 static LIST_HEAD(device_list);
128 static DEFINE_MUTEX(device_list_mutex);
129 
130 static LIST_HEAD(nvme_rdma_ctrl_list);
131 static DEFINE_MUTEX(nvme_rdma_ctrl_mutex);
132 
133 /*
134  * Disabling this option makes small I/O goes faster, but is fundamentally
135  * unsafe.  With it turned off we will have to register a global rkey that
136  * allows read and write access to all physical memory.
137  */
138 static bool register_always = true;
139 module_param(register_always, bool, 0444);
140 MODULE_PARM_DESC(register_always,
141 	 "Use memory registration even for contiguous memory regions");
142 
143 static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
144 		struct rdma_cm_event *event);
145 static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc);
146 
147 static const struct blk_mq_ops nvme_rdma_mq_ops;
148 static const struct blk_mq_ops nvme_rdma_admin_mq_ops;
149 
150 /* XXX: really should move to a generic header sooner or later.. */
151 static inline void put_unaligned_le24(u32 val, u8 *p)
152 {
153 	*p++ = val;
154 	*p++ = val >> 8;
155 	*p++ = val >> 16;
156 }
157 
158 static inline int nvme_rdma_queue_idx(struct nvme_rdma_queue *queue)
159 {
160 	return queue - queue->ctrl->queues;
161 }
162 
163 static inline size_t nvme_rdma_inline_data_size(struct nvme_rdma_queue *queue)
164 {
165 	return queue->cmnd_capsule_len - sizeof(struct nvme_command);
166 }
167 
168 static void nvme_rdma_free_qe(struct ib_device *ibdev, struct nvme_rdma_qe *qe,
169 		size_t capsule_size, enum dma_data_direction dir)
170 {
171 	ib_dma_unmap_single(ibdev, qe->dma, capsule_size, dir);
172 	kfree(qe->data);
173 }
174 
175 static int nvme_rdma_alloc_qe(struct ib_device *ibdev, struct nvme_rdma_qe *qe,
176 		size_t capsule_size, enum dma_data_direction dir)
177 {
178 	qe->data = kzalloc(capsule_size, GFP_KERNEL);
179 	if (!qe->data)
180 		return -ENOMEM;
181 
182 	qe->dma = ib_dma_map_single(ibdev, qe->data, capsule_size, dir);
183 	if (ib_dma_mapping_error(ibdev, qe->dma)) {
184 		kfree(qe->data);
185 		return -ENOMEM;
186 	}
187 
188 	return 0;
189 }
190 
191 static void nvme_rdma_free_ring(struct ib_device *ibdev,
192 		struct nvme_rdma_qe *ring, size_t ib_queue_size,
193 		size_t capsule_size, enum dma_data_direction dir)
194 {
195 	int i;
196 
197 	for (i = 0; i < ib_queue_size; i++)
198 		nvme_rdma_free_qe(ibdev, &ring[i], capsule_size, dir);
199 	kfree(ring);
200 }
201 
202 static struct nvme_rdma_qe *nvme_rdma_alloc_ring(struct ib_device *ibdev,
203 		size_t ib_queue_size, size_t capsule_size,
204 		enum dma_data_direction dir)
205 {
206 	struct nvme_rdma_qe *ring;
207 	int i;
208 
209 	ring = kcalloc(ib_queue_size, sizeof(struct nvme_rdma_qe), GFP_KERNEL);
210 	if (!ring)
211 		return NULL;
212 
213 	for (i = 0; i < ib_queue_size; i++) {
214 		if (nvme_rdma_alloc_qe(ibdev, &ring[i], capsule_size, dir))
215 			goto out_free_ring;
216 	}
217 
218 	return ring;
219 
220 out_free_ring:
221 	nvme_rdma_free_ring(ibdev, ring, i, capsule_size, dir);
222 	return NULL;
223 }
224 
225 static void nvme_rdma_qp_event(struct ib_event *event, void *context)
226 {
227 	pr_debug("QP event %s (%d)\n",
228 		 ib_event_msg(event->event), event->event);
229 
230 }
231 
232 static int nvme_rdma_wait_for_cm(struct nvme_rdma_queue *queue)
233 {
234 	wait_for_completion_interruptible_timeout(&queue->cm_done,
235 			msecs_to_jiffies(NVME_RDMA_CONNECT_TIMEOUT_MS) + 1);
236 	return queue->cm_error;
237 }
238 
239 static int nvme_rdma_create_qp(struct nvme_rdma_queue *queue, const int factor)
240 {
241 	struct nvme_rdma_device *dev = queue->device;
242 	struct ib_qp_init_attr init_attr;
243 	int ret;
244 
245 	memset(&init_attr, 0, sizeof(init_attr));
246 	init_attr.event_handler = nvme_rdma_qp_event;
247 	/* +1 for drain */
248 	init_attr.cap.max_send_wr = factor * queue->queue_size + 1;
249 	/* +1 for drain */
250 	init_attr.cap.max_recv_wr = queue->queue_size + 1;
251 	init_attr.cap.max_recv_sge = 1;
252 	init_attr.cap.max_send_sge = 1 + NVME_RDMA_MAX_INLINE_SEGMENTS;
253 	init_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
254 	init_attr.qp_type = IB_QPT_RC;
255 	init_attr.send_cq = queue->ib_cq;
256 	init_attr.recv_cq = queue->ib_cq;
257 
258 	ret = rdma_create_qp(queue->cm_id, dev->pd, &init_attr);
259 
260 	queue->qp = queue->cm_id->qp;
261 	return ret;
262 }
263 
264 static void nvme_rdma_exit_request(struct blk_mq_tag_set *set,
265 		struct request *rq, unsigned int hctx_idx)
266 {
267 	struct nvme_rdma_ctrl *ctrl = set->driver_data;
268 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
269 	int queue_idx = (set == &ctrl->tag_set) ? hctx_idx + 1 : 0;
270 	struct nvme_rdma_queue *queue = &ctrl->queues[queue_idx];
271 	struct nvme_rdma_device *dev = queue->device;
272 
273 	nvme_rdma_free_qe(dev->dev, &req->sqe, sizeof(struct nvme_command),
274 			DMA_TO_DEVICE);
275 }
276 
277 static int nvme_rdma_init_request(struct blk_mq_tag_set *set,
278 		struct request *rq, unsigned int hctx_idx,
279 		unsigned int numa_node)
280 {
281 	struct nvme_rdma_ctrl *ctrl = set->driver_data;
282 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
283 	int queue_idx = (set == &ctrl->tag_set) ? hctx_idx + 1 : 0;
284 	struct nvme_rdma_queue *queue = &ctrl->queues[queue_idx];
285 	struct nvme_rdma_device *dev = queue->device;
286 	struct ib_device *ibdev = dev->dev;
287 	int ret;
288 
289 	ret = nvme_rdma_alloc_qe(ibdev, &req->sqe, sizeof(struct nvme_command),
290 			DMA_TO_DEVICE);
291 	if (ret)
292 		return ret;
293 
294 	req->queue = queue;
295 
296 	return 0;
297 }
298 
299 static int nvme_rdma_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
300 		unsigned int hctx_idx)
301 {
302 	struct nvme_rdma_ctrl *ctrl = data;
303 	struct nvme_rdma_queue *queue = &ctrl->queues[hctx_idx + 1];
304 
305 	BUG_ON(hctx_idx >= ctrl->ctrl.queue_count);
306 
307 	hctx->driver_data = queue;
308 	return 0;
309 }
310 
311 static int nvme_rdma_init_admin_hctx(struct blk_mq_hw_ctx *hctx, void *data,
312 		unsigned int hctx_idx)
313 {
314 	struct nvme_rdma_ctrl *ctrl = data;
315 	struct nvme_rdma_queue *queue = &ctrl->queues[0];
316 
317 	BUG_ON(hctx_idx != 0);
318 
319 	hctx->driver_data = queue;
320 	return 0;
321 }
322 
323 static void nvme_rdma_free_dev(struct kref *ref)
324 {
325 	struct nvme_rdma_device *ndev =
326 		container_of(ref, struct nvme_rdma_device, ref);
327 
328 	mutex_lock(&device_list_mutex);
329 	list_del(&ndev->entry);
330 	mutex_unlock(&device_list_mutex);
331 
332 	ib_dealloc_pd(ndev->pd);
333 	kfree(ndev);
334 }
335 
336 static void nvme_rdma_dev_put(struct nvme_rdma_device *dev)
337 {
338 	kref_put(&dev->ref, nvme_rdma_free_dev);
339 }
340 
341 static int nvme_rdma_dev_get(struct nvme_rdma_device *dev)
342 {
343 	return kref_get_unless_zero(&dev->ref);
344 }
345 
346 static struct nvme_rdma_device *
347 nvme_rdma_find_get_device(struct rdma_cm_id *cm_id)
348 {
349 	struct nvme_rdma_device *ndev;
350 
351 	mutex_lock(&device_list_mutex);
352 	list_for_each_entry(ndev, &device_list, entry) {
353 		if (ndev->dev->node_guid == cm_id->device->node_guid &&
354 		    nvme_rdma_dev_get(ndev))
355 			goto out_unlock;
356 	}
357 
358 	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL);
359 	if (!ndev)
360 		goto out_err;
361 
362 	ndev->dev = cm_id->device;
363 	kref_init(&ndev->ref);
364 
365 	ndev->pd = ib_alloc_pd(ndev->dev,
366 		register_always ? 0 : IB_PD_UNSAFE_GLOBAL_RKEY);
367 	if (IS_ERR(ndev->pd))
368 		goto out_free_dev;
369 
370 	if (!(ndev->dev->attrs.device_cap_flags &
371 	      IB_DEVICE_MEM_MGT_EXTENSIONS)) {
372 		dev_err(&ndev->dev->dev,
373 			"Memory registrations not supported.\n");
374 		goto out_free_pd;
375 	}
376 
377 	list_add(&ndev->entry, &device_list);
378 out_unlock:
379 	mutex_unlock(&device_list_mutex);
380 	return ndev;
381 
382 out_free_pd:
383 	ib_dealloc_pd(ndev->pd);
384 out_free_dev:
385 	kfree(ndev);
386 out_err:
387 	mutex_unlock(&device_list_mutex);
388 	return NULL;
389 }
390 
391 static void nvme_rdma_destroy_queue_ib(struct nvme_rdma_queue *queue)
392 {
393 	struct nvme_rdma_device *dev;
394 	struct ib_device *ibdev;
395 
396 	if (!test_and_clear_bit(NVME_RDMA_Q_TR_READY, &queue->flags))
397 		return;
398 
399 	dev = queue->device;
400 	ibdev = dev->dev;
401 
402 	ib_mr_pool_destroy(queue->qp, &queue->qp->rdma_mrs);
403 
404 	/*
405 	 * The cm_id object might have been destroyed during RDMA connection
406 	 * establishment error flow to avoid getting other cma events, thus
407 	 * the destruction of the QP shouldn't use rdma_cm API.
408 	 */
409 	ib_destroy_qp(queue->qp);
410 	ib_free_cq(queue->ib_cq);
411 
412 	nvme_rdma_free_ring(ibdev, queue->rsp_ring, queue->queue_size,
413 			sizeof(struct nvme_completion), DMA_FROM_DEVICE);
414 
415 	nvme_rdma_dev_put(dev);
416 }
417 
418 static int nvme_rdma_get_max_fr_pages(struct ib_device *ibdev)
419 {
420 	return min_t(u32, NVME_RDMA_MAX_SEGMENTS,
421 		     ibdev->attrs.max_fast_reg_page_list_len);
422 }
423 
424 static int nvme_rdma_create_queue_ib(struct nvme_rdma_queue *queue)
425 {
426 	struct ib_device *ibdev;
427 	const int send_wr_factor = 3;			/* MR, SEND, INV */
428 	const int cq_factor = send_wr_factor + 1;	/* + RECV */
429 	int comp_vector, idx = nvme_rdma_queue_idx(queue);
430 	int ret;
431 
432 	queue->device = nvme_rdma_find_get_device(queue->cm_id);
433 	if (!queue->device) {
434 		dev_err(queue->cm_id->device->dev.parent,
435 			"no client data found!\n");
436 		return -ECONNREFUSED;
437 	}
438 	ibdev = queue->device->dev;
439 
440 	/*
441 	 * Spread I/O queues completion vectors according their queue index.
442 	 * Admin queues can always go on completion vector 0.
443 	 */
444 	comp_vector = idx == 0 ? idx : idx - 1;
445 
446 	/* +1 for ib_stop_cq */
447 	queue->ib_cq = ib_alloc_cq(ibdev, queue,
448 				cq_factor * queue->queue_size + 1,
449 				comp_vector, IB_POLL_SOFTIRQ);
450 	if (IS_ERR(queue->ib_cq)) {
451 		ret = PTR_ERR(queue->ib_cq);
452 		goto out_put_dev;
453 	}
454 
455 	ret = nvme_rdma_create_qp(queue, send_wr_factor);
456 	if (ret)
457 		goto out_destroy_ib_cq;
458 
459 	queue->rsp_ring = nvme_rdma_alloc_ring(ibdev, queue->queue_size,
460 			sizeof(struct nvme_completion), DMA_FROM_DEVICE);
461 	if (!queue->rsp_ring) {
462 		ret = -ENOMEM;
463 		goto out_destroy_qp;
464 	}
465 
466 	ret = ib_mr_pool_init(queue->qp, &queue->qp->rdma_mrs,
467 			      queue->queue_size,
468 			      IB_MR_TYPE_MEM_REG,
469 			      nvme_rdma_get_max_fr_pages(ibdev));
470 	if (ret) {
471 		dev_err(queue->ctrl->ctrl.device,
472 			"failed to initialize MR pool sized %d for QID %d\n",
473 			queue->queue_size, idx);
474 		goto out_destroy_ring;
475 	}
476 
477 	set_bit(NVME_RDMA_Q_TR_READY, &queue->flags);
478 
479 	return 0;
480 
481 out_destroy_ring:
482 	nvme_rdma_free_ring(ibdev, queue->rsp_ring, queue->queue_size,
483 			    sizeof(struct nvme_completion), DMA_FROM_DEVICE);
484 out_destroy_qp:
485 	rdma_destroy_qp(queue->cm_id);
486 out_destroy_ib_cq:
487 	ib_free_cq(queue->ib_cq);
488 out_put_dev:
489 	nvme_rdma_dev_put(queue->device);
490 	return ret;
491 }
492 
493 static int nvme_rdma_alloc_queue(struct nvme_rdma_ctrl *ctrl,
494 		int idx, size_t queue_size)
495 {
496 	struct nvme_rdma_queue *queue;
497 	struct sockaddr *src_addr = NULL;
498 	int ret;
499 
500 	queue = &ctrl->queues[idx];
501 	queue->ctrl = ctrl;
502 	init_completion(&queue->cm_done);
503 
504 	if (idx > 0)
505 		queue->cmnd_capsule_len = ctrl->ctrl.ioccsz * 16;
506 	else
507 		queue->cmnd_capsule_len = sizeof(struct nvme_command);
508 
509 	queue->queue_size = queue_size;
510 
511 	queue->cm_id = rdma_create_id(&init_net, nvme_rdma_cm_handler, queue,
512 			RDMA_PS_TCP, IB_QPT_RC);
513 	if (IS_ERR(queue->cm_id)) {
514 		dev_info(ctrl->ctrl.device,
515 			"failed to create CM ID: %ld\n", PTR_ERR(queue->cm_id));
516 		return PTR_ERR(queue->cm_id);
517 	}
518 
519 	if (ctrl->ctrl.opts->mask & NVMF_OPT_HOST_TRADDR)
520 		src_addr = (struct sockaddr *)&ctrl->src_addr;
521 
522 	queue->cm_error = -ETIMEDOUT;
523 	ret = rdma_resolve_addr(queue->cm_id, src_addr,
524 			(struct sockaddr *)&ctrl->addr,
525 			NVME_RDMA_CONNECT_TIMEOUT_MS);
526 	if (ret) {
527 		dev_info(ctrl->ctrl.device,
528 			"rdma_resolve_addr failed (%d).\n", ret);
529 		goto out_destroy_cm_id;
530 	}
531 
532 	ret = nvme_rdma_wait_for_cm(queue);
533 	if (ret) {
534 		dev_info(ctrl->ctrl.device,
535 			"rdma connection establishment failed (%d)\n", ret);
536 		goto out_destroy_cm_id;
537 	}
538 
539 	set_bit(NVME_RDMA_Q_ALLOCATED, &queue->flags);
540 
541 	return 0;
542 
543 out_destroy_cm_id:
544 	rdma_destroy_id(queue->cm_id);
545 	nvme_rdma_destroy_queue_ib(queue);
546 	return ret;
547 }
548 
549 static void nvme_rdma_stop_queue(struct nvme_rdma_queue *queue)
550 {
551 	if (!test_and_clear_bit(NVME_RDMA_Q_LIVE, &queue->flags))
552 		return;
553 
554 	rdma_disconnect(queue->cm_id);
555 	ib_drain_qp(queue->qp);
556 }
557 
558 static void nvme_rdma_free_queue(struct nvme_rdma_queue *queue)
559 {
560 	if (!test_and_clear_bit(NVME_RDMA_Q_ALLOCATED, &queue->flags))
561 		return;
562 
563 	nvme_rdma_destroy_queue_ib(queue);
564 	rdma_destroy_id(queue->cm_id);
565 }
566 
567 static void nvme_rdma_free_io_queues(struct nvme_rdma_ctrl *ctrl)
568 {
569 	int i;
570 
571 	for (i = 1; i < ctrl->ctrl.queue_count; i++)
572 		nvme_rdma_free_queue(&ctrl->queues[i]);
573 }
574 
575 static void nvme_rdma_stop_io_queues(struct nvme_rdma_ctrl *ctrl)
576 {
577 	int i;
578 
579 	for (i = 1; i < ctrl->ctrl.queue_count; i++)
580 		nvme_rdma_stop_queue(&ctrl->queues[i]);
581 }
582 
583 static int nvme_rdma_start_queue(struct nvme_rdma_ctrl *ctrl, int idx)
584 {
585 	int ret;
586 
587 	if (idx)
588 		ret = nvmf_connect_io_queue(&ctrl->ctrl, idx);
589 	else
590 		ret = nvmf_connect_admin_queue(&ctrl->ctrl);
591 
592 	if (!ret)
593 		set_bit(NVME_RDMA_Q_LIVE, &ctrl->queues[idx].flags);
594 	else
595 		dev_info(ctrl->ctrl.device,
596 			"failed to connect queue: %d ret=%d\n", idx, ret);
597 	return ret;
598 }
599 
600 static int nvme_rdma_start_io_queues(struct nvme_rdma_ctrl *ctrl)
601 {
602 	int i, ret = 0;
603 
604 	for (i = 1; i < ctrl->ctrl.queue_count; i++) {
605 		ret = nvme_rdma_start_queue(ctrl, i);
606 		if (ret)
607 			goto out_stop_queues;
608 	}
609 
610 	return 0;
611 
612 out_stop_queues:
613 	for (i--; i >= 1; i--)
614 		nvme_rdma_stop_queue(&ctrl->queues[i]);
615 	return ret;
616 }
617 
618 static int nvme_rdma_alloc_io_queues(struct nvme_rdma_ctrl *ctrl)
619 {
620 	struct nvmf_ctrl_options *opts = ctrl->ctrl.opts;
621 	struct ib_device *ibdev = ctrl->device->dev;
622 	unsigned int nr_io_queues;
623 	int i, ret;
624 
625 	nr_io_queues = min(opts->nr_io_queues, num_online_cpus());
626 
627 	/*
628 	 * we map queues according to the device irq vectors for
629 	 * optimal locality so we don't need more queues than
630 	 * completion vectors.
631 	 */
632 	nr_io_queues = min_t(unsigned int, nr_io_queues,
633 				ibdev->num_comp_vectors);
634 
635 	ret = nvme_set_queue_count(&ctrl->ctrl, &nr_io_queues);
636 	if (ret)
637 		return ret;
638 
639 	ctrl->ctrl.queue_count = nr_io_queues + 1;
640 	if (ctrl->ctrl.queue_count < 2)
641 		return 0;
642 
643 	dev_info(ctrl->ctrl.device,
644 		"creating %d I/O queues.\n", nr_io_queues);
645 
646 	for (i = 1; i < ctrl->ctrl.queue_count; i++) {
647 		ret = nvme_rdma_alloc_queue(ctrl, i,
648 				ctrl->ctrl.sqsize + 1);
649 		if (ret)
650 			goto out_free_queues;
651 	}
652 
653 	return 0;
654 
655 out_free_queues:
656 	for (i--; i >= 1; i--)
657 		nvme_rdma_free_queue(&ctrl->queues[i]);
658 
659 	return ret;
660 }
661 
662 static void nvme_rdma_free_tagset(struct nvme_ctrl *nctrl,
663 		struct blk_mq_tag_set *set)
664 {
665 	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
666 
667 	blk_mq_free_tag_set(set);
668 	nvme_rdma_dev_put(ctrl->device);
669 }
670 
671 static struct blk_mq_tag_set *nvme_rdma_alloc_tagset(struct nvme_ctrl *nctrl,
672 		bool admin)
673 {
674 	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
675 	struct blk_mq_tag_set *set;
676 	int ret;
677 
678 	if (admin) {
679 		set = &ctrl->admin_tag_set;
680 		memset(set, 0, sizeof(*set));
681 		set->ops = &nvme_rdma_admin_mq_ops;
682 		set->queue_depth = NVME_AQ_MQ_TAG_DEPTH;
683 		set->reserved_tags = 2; /* connect + keep-alive */
684 		set->numa_node = NUMA_NO_NODE;
685 		set->cmd_size = sizeof(struct nvme_rdma_request) +
686 			SG_CHUNK_SIZE * sizeof(struct scatterlist);
687 		set->driver_data = ctrl;
688 		set->nr_hw_queues = 1;
689 		set->timeout = ADMIN_TIMEOUT;
690 		set->flags = BLK_MQ_F_NO_SCHED;
691 	} else {
692 		set = &ctrl->tag_set;
693 		memset(set, 0, sizeof(*set));
694 		set->ops = &nvme_rdma_mq_ops;
695 		set->queue_depth = nctrl->sqsize + 1;
696 		set->reserved_tags = 1; /* fabric connect */
697 		set->numa_node = NUMA_NO_NODE;
698 		set->flags = BLK_MQ_F_SHOULD_MERGE;
699 		set->cmd_size = sizeof(struct nvme_rdma_request) +
700 			SG_CHUNK_SIZE * sizeof(struct scatterlist);
701 		set->driver_data = ctrl;
702 		set->nr_hw_queues = nctrl->queue_count - 1;
703 		set->timeout = NVME_IO_TIMEOUT;
704 	}
705 
706 	ret = blk_mq_alloc_tag_set(set);
707 	if (ret)
708 		goto out;
709 
710 	/*
711 	 * We need a reference on the device as long as the tag_set is alive,
712 	 * as the MRs in the request structures need a valid ib_device.
713 	 */
714 	ret = nvme_rdma_dev_get(ctrl->device);
715 	if (!ret) {
716 		ret = -EINVAL;
717 		goto out_free_tagset;
718 	}
719 
720 	return set;
721 
722 out_free_tagset:
723 	blk_mq_free_tag_set(set);
724 out:
725 	return ERR_PTR(ret);
726 }
727 
728 static void nvme_rdma_destroy_admin_queue(struct nvme_rdma_ctrl *ctrl,
729 		bool remove)
730 {
731 	if (remove) {
732 		blk_cleanup_queue(ctrl->ctrl.admin_q);
733 		nvme_rdma_free_tagset(&ctrl->ctrl, ctrl->ctrl.admin_tagset);
734 	}
735 	nvme_rdma_free_qe(ctrl->device->dev, &ctrl->async_event_sqe,
736 		sizeof(struct nvme_command), DMA_TO_DEVICE);
737 	nvme_rdma_free_queue(&ctrl->queues[0]);
738 }
739 
740 static int nvme_rdma_configure_admin_queue(struct nvme_rdma_ctrl *ctrl,
741 		bool new)
742 {
743 	int error;
744 
745 	error = nvme_rdma_alloc_queue(ctrl, 0, NVME_AQ_DEPTH);
746 	if (error)
747 		return error;
748 
749 	ctrl->device = ctrl->queues[0].device;
750 
751 	ctrl->max_fr_pages = nvme_rdma_get_max_fr_pages(ctrl->device->dev);
752 
753 	error = nvme_rdma_alloc_qe(ctrl->device->dev, &ctrl->async_event_sqe,
754 			sizeof(struct nvme_command), DMA_TO_DEVICE);
755 	if (error)
756 		goto out_free_queue;
757 
758 	if (new) {
759 		ctrl->ctrl.admin_tagset = nvme_rdma_alloc_tagset(&ctrl->ctrl, true);
760 		if (IS_ERR(ctrl->ctrl.admin_tagset)) {
761 			error = PTR_ERR(ctrl->ctrl.admin_tagset);
762 			goto out_free_async_qe;
763 		}
764 
765 		ctrl->ctrl.admin_q = blk_mq_init_queue(&ctrl->admin_tag_set);
766 		if (IS_ERR(ctrl->ctrl.admin_q)) {
767 			error = PTR_ERR(ctrl->ctrl.admin_q);
768 			goto out_free_tagset;
769 		}
770 	}
771 
772 	error = nvme_rdma_start_queue(ctrl, 0);
773 	if (error)
774 		goto out_cleanup_queue;
775 
776 	error = ctrl->ctrl.ops->reg_read64(&ctrl->ctrl, NVME_REG_CAP,
777 			&ctrl->ctrl.cap);
778 	if (error) {
779 		dev_err(ctrl->ctrl.device,
780 			"prop_get NVME_REG_CAP failed\n");
781 		goto out_stop_queue;
782 	}
783 
784 	ctrl->ctrl.sqsize =
785 		min_t(int, NVME_CAP_MQES(ctrl->ctrl.cap), ctrl->ctrl.sqsize);
786 
787 	error = nvme_enable_ctrl(&ctrl->ctrl, ctrl->ctrl.cap);
788 	if (error)
789 		goto out_stop_queue;
790 
791 	ctrl->ctrl.max_hw_sectors =
792 		(ctrl->max_fr_pages - 1) << (ilog2(SZ_4K) - 9);
793 
794 	error = nvme_init_identify(&ctrl->ctrl);
795 	if (error)
796 		goto out_stop_queue;
797 
798 	return 0;
799 
800 out_stop_queue:
801 	nvme_rdma_stop_queue(&ctrl->queues[0]);
802 out_cleanup_queue:
803 	if (new)
804 		blk_cleanup_queue(ctrl->ctrl.admin_q);
805 out_free_tagset:
806 	if (new)
807 		nvme_rdma_free_tagset(&ctrl->ctrl, ctrl->ctrl.admin_tagset);
808 out_free_async_qe:
809 	nvme_rdma_free_qe(ctrl->device->dev, &ctrl->async_event_sqe,
810 		sizeof(struct nvme_command), DMA_TO_DEVICE);
811 out_free_queue:
812 	nvme_rdma_free_queue(&ctrl->queues[0]);
813 	return error;
814 }
815 
816 static void nvme_rdma_destroy_io_queues(struct nvme_rdma_ctrl *ctrl,
817 		bool remove)
818 {
819 	if (remove) {
820 		blk_cleanup_queue(ctrl->ctrl.connect_q);
821 		nvme_rdma_free_tagset(&ctrl->ctrl, ctrl->ctrl.tagset);
822 	}
823 	nvme_rdma_free_io_queues(ctrl);
824 }
825 
826 static int nvme_rdma_configure_io_queues(struct nvme_rdma_ctrl *ctrl, bool new)
827 {
828 	int ret;
829 
830 	ret = nvme_rdma_alloc_io_queues(ctrl);
831 	if (ret)
832 		return ret;
833 
834 	if (new) {
835 		ctrl->ctrl.tagset = nvme_rdma_alloc_tagset(&ctrl->ctrl, false);
836 		if (IS_ERR(ctrl->ctrl.tagset)) {
837 			ret = PTR_ERR(ctrl->ctrl.tagset);
838 			goto out_free_io_queues;
839 		}
840 
841 		ctrl->ctrl.connect_q = blk_mq_init_queue(&ctrl->tag_set);
842 		if (IS_ERR(ctrl->ctrl.connect_q)) {
843 			ret = PTR_ERR(ctrl->ctrl.connect_q);
844 			goto out_free_tag_set;
845 		}
846 	} else {
847 		blk_mq_update_nr_hw_queues(&ctrl->tag_set,
848 			ctrl->ctrl.queue_count - 1);
849 	}
850 
851 	ret = nvme_rdma_start_io_queues(ctrl);
852 	if (ret)
853 		goto out_cleanup_connect_q;
854 
855 	return 0;
856 
857 out_cleanup_connect_q:
858 	if (new)
859 		blk_cleanup_queue(ctrl->ctrl.connect_q);
860 out_free_tag_set:
861 	if (new)
862 		nvme_rdma_free_tagset(&ctrl->ctrl, ctrl->ctrl.tagset);
863 out_free_io_queues:
864 	nvme_rdma_free_io_queues(ctrl);
865 	return ret;
866 }
867 
868 static void nvme_rdma_stop_ctrl(struct nvme_ctrl *nctrl)
869 {
870 	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
871 
872 	cancel_work_sync(&ctrl->err_work);
873 	cancel_delayed_work_sync(&ctrl->reconnect_work);
874 }
875 
876 static void nvme_rdma_free_ctrl(struct nvme_ctrl *nctrl)
877 {
878 	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(nctrl);
879 
880 	if (list_empty(&ctrl->list))
881 		goto free_ctrl;
882 
883 	mutex_lock(&nvme_rdma_ctrl_mutex);
884 	list_del(&ctrl->list);
885 	mutex_unlock(&nvme_rdma_ctrl_mutex);
886 
887 	nvmf_free_options(nctrl->opts);
888 free_ctrl:
889 	kfree(ctrl->queues);
890 	kfree(ctrl);
891 }
892 
893 static void nvme_rdma_reconnect_or_remove(struct nvme_rdma_ctrl *ctrl)
894 {
895 	/* If we are resetting/deleting then do nothing */
896 	if (ctrl->ctrl.state != NVME_CTRL_CONNECTING) {
897 		WARN_ON_ONCE(ctrl->ctrl.state == NVME_CTRL_NEW ||
898 			ctrl->ctrl.state == NVME_CTRL_LIVE);
899 		return;
900 	}
901 
902 	if (nvmf_should_reconnect(&ctrl->ctrl)) {
903 		dev_info(ctrl->ctrl.device, "Reconnecting in %d seconds...\n",
904 			ctrl->ctrl.opts->reconnect_delay);
905 		queue_delayed_work(nvme_wq, &ctrl->reconnect_work,
906 				ctrl->ctrl.opts->reconnect_delay * HZ);
907 	} else {
908 		nvme_delete_ctrl(&ctrl->ctrl);
909 	}
910 }
911 
912 static void nvme_rdma_reconnect_ctrl_work(struct work_struct *work)
913 {
914 	struct nvme_rdma_ctrl *ctrl = container_of(to_delayed_work(work),
915 			struct nvme_rdma_ctrl, reconnect_work);
916 	bool changed;
917 	int ret;
918 
919 	++ctrl->ctrl.nr_reconnects;
920 
921 	ret = nvme_rdma_configure_admin_queue(ctrl, false);
922 	if (ret)
923 		goto requeue;
924 
925 	if (ctrl->ctrl.queue_count > 1) {
926 		ret = nvme_rdma_configure_io_queues(ctrl, false);
927 		if (ret)
928 			goto destroy_admin;
929 	}
930 
931 	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
932 	if (!changed) {
933 		/* state change failure is ok if we're in DELETING state */
934 		WARN_ON_ONCE(ctrl->ctrl.state != NVME_CTRL_DELETING);
935 		return;
936 	}
937 
938 	nvme_start_ctrl(&ctrl->ctrl);
939 
940 	dev_info(ctrl->ctrl.device, "Successfully reconnected (%d attempts)\n",
941 			ctrl->ctrl.nr_reconnects);
942 
943 	ctrl->ctrl.nr_reconnects = 0;
944 
945 	return;
946 
947 destroy_admin:
948 	nvme_rdma_stop_queue(&ctrl->queues[0]);
949 	nvme_rdma_destroy_admin_queue(ctrl, false);
950 requeue:
951 	dev_info(ctrl->ctrl.device, "Failed reconnect attempt %d\n",
952 			ctrl->ctrl.nr_reconnects);
953 	nvme_rdma_reconnect_or_remove(ctrl);
954 }
955 
956 static void nvme_rdma_error_recovery_work(struct work_struct *work)
957 {
958 	struct nvme_rdma_ctrl *ctrl = container_of(work,
959 			struct nvme_rdma_ctrl, err_work);
960 
961 	nvme_stop_keep_alive(&ctrl->ctrl);
962 
963 	if (ctrl->ctrl.queue_count > 1) {
964 		nvme_stop_queues(&ctrl->ctrl);
965 		nvme_rdma_stop_io_queues(ctrl);
966 		blk_mq_tagset_busy_iter(&ctrl->tag_set,
967 					nvme_cancel_request, &ctrl->ctrl);
968 		nvme_rdma_destroy_io_queues(ctrl, false);
969 	}
970 
971 	blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
972 	nvme_rdma_stop_queue(&ctrl->queues[0]);
973 	blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
974 				nvme_cancel_request, &ctrl->ctrl);
975 	nvme_rdma_destroy_admin_queue(ctrl, false);
976 
977 	/*
978 	 * queues are not a live anymore, so restart the queues to fail fast
979 	 * new IO
980 	 */
981 	blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
982 	nvme_start_queues(&ctrl->ctrl);
983 
984 	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) {
985 		/* state change failure is ok if we're in DELETING state */
986 		WARN_ON_ONCE(ctrl->ctrl.state != NVME_CTRL_DELETING);
987 		return;
988 	}
989 
990 	nvme_rdma_reconnect_or_remove(ctrl);
991 }
992 
993 static void nvme_rdma_error_recovery(struct nvme_rdma_ctrl *ctrl)
994 {
995 	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_RESETTING))
996 		return;
997 
998 	queue_work(nvme_wq, &ctrl->err_work);
999 }
1000 
1001 static void nvme_rdma_wr_error(struct ib_cq *cq, struct ib_wc *wc,
1002 		const char *op)
1003 {
1004 	struct nvme_rdma_queue *queue = cq->cq_context;
1005 	struct nvme_rdma_ctrl *ctrl = queue->ctrl;
1006 
1007 	if (ctrl->ctrl.state == NVME_CTRL_LIVE)
1008 		dev_info(ctrl->ctrl.device,
1009 			     "%s for CQE 0x%p failed with status %s (%d)\n",
1010 			     op, wc->wr_cqe,
1011 			     ib_wc_status_msg(wc->status), wc->status);
1012 	nvme_rdma_error_recovery(ctrl);
1013 }
1014 
1015 static void nvme_rdma_memreg_done(struct ib_cq *cq, struct ib_wc *wc)
1016 {
1017 	if (unlikely(wc->status != IB_WC_SUCCESS))
1018 		nvme_rdma_wr_error(cq, wc, "MEMREG");
1019 }
1020 
1021 static void nvme_rdma_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc)
1022 {
1023 	struct nvme_rdma_request *req =
1024 		container_of(wc->wr_cqe, struct nvme_rdma_request, reg_cqe);
1025 	struct request *rq = blk_mq_rq_from_pdu(req);
1026 
1027 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1028 		nvme_rdma_wr_error(cq, wc, "LOCAL_INV");
1029 		return;
1030 	}
1031 
1032 	if (refcount_dec_and_test(&req->ref))
1033 		nvme_end_request(rq, req->status, req->result);
1034 
1035 }
1036 
1037 static int nvme_rdma_inv_rkey(struct nvme_rdma_queue *queue,
1038 		struct nvme_rdma_request *req)
1039 {
1040 	struct ib_send_wr *bad_wr;
1041 	struct ib_send_wr wr = {
1042 		.opcode		    = IB_WR_LOCAL_INV,
1043 		.next		    = NULL,
1044 		.num_sge	    = 0,
1045 		.send_flags	    = IB_SEND_SIGNALED,
1046 		.ex.invalidate_rkey = req->mr->rkey,
1047 	};
1048 
1049 	req->reg_cqe.done = nvme_rdma_inv_rkey_done;
1050 	wr.wr_cqe = &req->reg_cqe;
1051 
1052 	return ib_post_send(queue->qp, &wr, &bad_wr);
1053 }
1054 
1055 static void nvme_rdma_unmap_data(struct nvme_rdma_queue *queue,
1056 		struct request *rq)
1057 {
1058 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1059 	struct nvme_rdma_device *dev = queue->device;
1060 	struct ib_device *ibdev = dev->dev;
1061 
1062 	if (!blk_rq_payload_bytes(rq))
1063 		return;
1064 
1065 	if (req->mr) {
1066 		ib_mr_pool_put(queue->qp, &queue->qp->rdma_mrs, req->mr);
1067 		req->mr = NULL;
1068 	}
1069 
1070 	ib_dma_unmap_sg(ibdev, req->sg_table.sgl,
1071 			req->nents, rq_data_dir(rq) ==
1072 				    WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
1073 
1074 	nvme_cleanup_cmd(rq);
1075 	sg_free_table_chained(&req->sg_table, true);
1076 }
1077 
1078 static int nvme_rdma_set_sg_null(struct nvme_command *c)
1079 {
1080 	struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
1081 
1082 	sg->addr = 0;
1083 	put_unaligned_le24(0, sg->length);
1084 	put_unaligned_le32(0, sg->key);
1085 	sg->type = NVME_KEY_SGL_FMT_DATA_DESC << 4;
1086 	return 0;
1087 }
1088 
1089 static int nvme_rdma_map_sg_inline(struct nvme_rdma_queue *queue,
1090 		struct nvme_rdma_request *req, struct nvme_command *c)
1091 {
1092 	struct nvme_sgl_desc *sg = &c->common.dptr.sgl;
1093 
1094 	req->sge[1].addr = sg_dma_address(req->sg_table.sgl);
1095 	req->sge[1].length = sg_dma_len(req->sg_table.sgl);
1096 	req->sge[1].lkey = queue->device->pd->local_dma_lkey;
1097 
1098 	sg->addr = cpu_to_le64(queue->ctrl->ctrl.icdoff);
1099 	sg->length = cpu_to_le32(sg_dma_len(req->sg_table.sgl));
1100 	sg->type = (NVME_SGL_FMT_DATA_DESC << 4) | NVME_SGL_FMT_OFFSET;
1101 
1102 	req->num_sge++;
1103 	return 0;
1104 }
1105 
1106 static int nvme_rdma_map_sg_single(struct nvme_rdma_queue *queue,
1107 		struct nvme_rdma_request *req, struct nvme_command *c)
1108 {
1109 	struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
1110 
1111 	sg->addr = cpu_to_le64(sg_dma_address(req->sg_table.sgl));
1112 	put_unaligned_le24(sg_dma_len(req->sg_table.sgl), sg->length);
1113 	put_unaligned_le32(queue->device->pd->unsafe_global_rkey, sg->key);
1114 	sg->type = NVME_KEY_SGL_FMT_DATA_DESC << 4;
1115 	return 0;
1116 }
1117 
1118 static int nvme_rdma_map_sg_fr(struct nvme_rdma_queue *queue,
1119 		struct nvme_rdma_request *req, struct nvme_command *c,
1120 		int count)
1121 {
1122 	struct nvme_keyed_sgl_desc *sg = &c->common.dptr.ksgl;
1123 	int nr;
1124 
1125 	req->mr = ib_mr_pool_get(queue->qp, &queue->qp->rdma_mrs);
1126 	if (WARN_ON_ONCE(!req->mr))
1127 		return -EAGAIN;
1128 
1129 	/*
1130 	 * Align the MR to a 4K page size to match the ctrl page size and
1131 	 * the block virtual boundary.
1132 	 */
1133 	nr = ib_map_mr_sg(req->mr, req->sg_table.sgl, count, NULL, SZ_4K);
1134 	if (unlikely(nr < count)) {
1135 		ib_mr_pool_put(queue->qp, &queue->qp->rdma_mrs, req->mr);
1136 		req->mr = NULL;
1137 		if (nr < 0)
1138 			return nr;
1139 		return -EINVAL;
1140 	}
1141 
1142 	ib_update_fast_reg_key(req->mr, ib_inc_rkey(req->mr->rkey));
1143 
1144 	req->reg_cqe.done = nvme_rdma_memreg_done;
1145 	memset(&req->reg_wr, 0, sizeof(req->reg_wr));
1146 	req->reg_wr.wr.opcode = IB_WR_REG_MR;
1147 	req->reg_wr.wr.wr_cqe = &req->reg_cqe;
1148 	req->reg_wr.wr.num_sge = 0;
1149 	req->reg_wr.mr = req->mr;
1150 	req->reg_wr.key = req->mr->rkey;
1151 	req->reg_wr.access = IB_ACCESS_LOCAL_WRITE |
1152 			     IB_ACCESS_REMOTE_READ |
1153 			     IB_ACCESS_REMOTE_WRITE;
1154 
1155 	sg->addr = cpu_to_le64(req->mr->iova);
1156 	put_unaligned_le24(req->mr->length, sg->length);
1157 	put_unaligned_le32(req->mr->rkey, sg->key);
1158 	sg->type = (NVME_KEY_SGL_FMT_DATA_DESC << 4) |
1159 			NVME_SGL_FMT_INVALIDATE;
1160 
1161 	return 0;
1162 }
1163 
1164 static int nvme_rdma_map_data(struct nvme_rdma_queue *queue,
1165 		struct request *rq, struct nvme_command *c)
1166 {
1167 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1168 	struct nvme_rdma_device *dev = queue->device;
1169 	struct ib_device *ibdev = dev->dev;
1170 	int count, ret;
1171 
1172 	req->num_sge = 1;
1173 	refcount_set(&req->ref, 2); /* send and recv completions */
1174 
1175 	c->common.flags |= NVME_CMD_SGL_METABUF;
1176 
1177 	if (!blk_rq_payload_bytes(rq))
1178 		return nvme_rdma_set_sg_null(c);
1179 
1180 	req->sg_table.sgl = req->first_sgl;
1181 	ret = sg_alloc_table_chained(&req->sg_table,
1182 			blk_rq_nr_phys_segments(rq), req->sg_table.sgl);
1183 	if (ret)
1184 		return -ENOMEM;
1185 
1186 	req->nents = blk_rq_map_sg(rq->q, rq, req->sg_table.sgl);
1187 
1188 	count = ib_dma_map_sg(ibdev, req->sg_table.sgl, req->nents,
1189 		    rq_data_dir(rq) == WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
1190 	if (unlikely(count <= 0)) {
1191 		ret = -EIO;
1192 		goto out_free_table;
1193 	}
1194 
1195 	if (count == 1) {
1196 		if (rq_data_dir(rq) == WRITE && nvme_rdma_queue_idx(queue) &&
1197 		    blk_rq_payload_bytes(rq) <=
1198 				nvme_rdma_inline_data_size(queue)) {
1199 			ret = nvme_rdma_map_sg_inline(queue, req, c);
1200 			goto out;
1201 		}
1202 
1203 		if (dev->pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY) {
1204 			ret = nvme_rdma_map_sg_single(queue, req, c);
1205 			goto out;
1206 		}
1207 	}
1208 
1209 	ret = nvme_rdma_map_sg_fr(queue, req, c, count);
1210 out:
1211 	if (unlikely(ret))
1212 		goto out_unmap_sg;
1213 
1214 	return 0;
1215 
1216 out_unmap_sg:
1217 	ib_dma_unmap_sg(ibdev, req->sg_table.sgl,
1218 			req->nents, rq_data_dir(rq) ==
1219 			WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
1220 out_free_table:
1221 	sg_free_table_chained(&req->sg_table, true);
1222 	return ret;
1223 }
1224 
1225 static void nvme_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc)
1226 {
1227 	struct nvme_rdma_qe *qe =
1228 		container_of(wc->wr_cqe, struct nvme_rdma_qe, cqe);
1229 	struct nvme_rdma_request *req =
1230 		container_of(qe, struct nvme_rdma_request, sqe);
1231 	struct request *rq = blk_mq_rq_from_pdu(req);
1232 
1233 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1234 		nvme_rdma_wr_error(cq, wc, "SEND");
1235 		return;
1236 	}
1237 
1238 	if (refcount_dec_and_test(&req->ref))
1239 		nvme_end_request(rq, req->status, req->result);
1240 }
1241 
1242 static int nvme_rdma_post_send(struct nvme_rdma_queue *queue,
1243 		struct nvme_rdma_qe *qe, struct ib_sge *sge, u32 num_sge,
1244 		struct ib_send_wr *first)
1245 {
1246 	struct ib_send_wr wr, *bad_wr;
1247 	int ret;
1248 
1249 	sge->addr   = qe->dma;
1250 	sge->length = sizeof(struct nvme_command),
1251 	sge->lkey   = queue->device->pd->local_dma_lkey;
1252 
1253 	wr.next       = NULL;
1254 	wr.wr_cqe     = &qe->cqe;
1255 	wr.sg_list    = sge;
1256 	wr.num_sge    = num_sge;
1257 	wr.opcode     = IB_WR_SEND;
1258 	wr.send_flags = IB_SEND_SIGNALED;
1259 
1260 	if (first)
1261 		first->next = &wr;
1262 	else
1263 		first = &wr;
1264 
1265 	ret = ib_post_send(queue->qp, first, &bad_wr);
1266 	if (unlikely(ret)) {
1267 		dev_err(queue->ctrl->ctrl.device,
1268 			     "%s failed with error code %d\n", __func__, ret);
1269 	}
1270 	return ret;
1271 }
1272 
1273 static int nvme_rdma_post_recv(struct nvme_rdma_queue *queue,
1274 		struct nvme_rdma_qe *qe)
1275 {
1276 	struct ib_recv_wr wr, *bad_wr;
1277 	struct ib_sge list;
1278 	int ret;
1279 
1280 	list.addr   = qe->dma;
1281 	list.length = sizeof(struct nvme_completion);
1282 	list.lkey   = queue->device->pd->local_dma_lkey;
1283 
1284 	qe->cqe.done = nvme_rdma_recv_done;
1285 
1286 	wr.next     = NULL;
1287 	wr.wr_cqe   = &qe->cqe;
1288 	wr.sg_list  = &list;
1289 	wr.num_sge  = 1;
1290 
1291 	ret = ib_post_recv(queue->qp, &wr, &bad_wr);
1292 	if (unlikely(ret)) {
1293 		dev_err(queue->ctrl->ctrl.device,
1294 			"%s failed with error code %d\n", __func__, ret);
1295 	}
1296 	return ret;
1297 }
1298 
1299 static struct blk_mq_tags *nvme_rdma_tagset(struct nvme_rdma_queue *queue)
1300 {
1301 	u32 queue_idx = nvme_rdma_queue_idx(queue);
1302 
1303 	if (queue_idx == 0)
1304 		return queue->ctrl->admin_tag_set.tags[queue_idx];
1305 	return queue->ctrl->tag_set.tags[queue_idx - 1];
1306 }
1307 
1308 static void nvme_rdma_async_done(struct ib_cq *cq, struct ib_wc *wc)
1309 {
1310 	if (unlikely(wc->status != IB_WC_SUCCESS))
1311 		nvme_rdma_wr_error(cq, wc, "ASYNC");
1312 }
1313 
1314 static void nvme_rdma_submit_async_event(struct nvme_ctrl *arg)
1315 {
1316 	struct nvme_rdma_ctrl *ctrl = to_rdma_ctrl(arg);
1317 	struct nvme_rdma_queue *queue = &ctrl->queues[0];
1318 	struct ib_device *dev = queue->device->dev;
1319 	struct nvme_rdma_qe *sqe = &ctrl->async_event_sqe;
1320 	struct nvme_command *cmd = sqe->data;
1321 	struct ib_sge sge;
1322 	int ret;
1323 
1324 	ib_dma_sync_single_for_cpu(dev, sqe->dma, sizeof(*cmd), DMA_TO_DEVICE);
1325 
1326 	memset(cmd, 0, sizeof(*cmd));
1327 	cmd->common.opcode = nvme_admin_async_event;
1328 	cmd->common.command_id = NVME_AQ_BLK_MQ_DEPTH;
1329 	cmd->common.flags |= NVME_CMD_SGL_METABUF;
1330 	nvme_rdma_set_sg_null(cmd);
1331 
1332 	sqe->cqe.done = nvme_rdma_async_done;
1333 
1334 	ib_dma_sync_single_for_device(dev, sqe->dma, sizeof(*cmd),
1335 			DMA_TO_DEVICE);
1336 
1337 	ret = nvme_rdma_post_send(queue, sqe, &sge, 1, NULL);
1338 	WARN_ON_ONCE(ret);
1339 }
1340 
1341 static int nvme_rdma_process_nvme_rsp(struct nvme_rdma_queue *queue,
1342 		struct nvme_completion *cqe, struct ib_wc *wc, int tag)
1343 {
1344 	struct request *rq;
1345 	struct nvme_rdma_request *req;
1346 	int ret = 0;
1347 
1348 	rq = blk_mq_tag_to_rq(nvme_rdma_tagset(queue), cqe->command_id);
1349 	if (!rq) {
1350 		dev_err(queue->ctrl->ctrl.device,
1351 			"tag 0x%x on QP %#x not found\n",
1352 			cqe->command_id, queue->qp->qp_num);
1353 		nvme_rdma_error_recovery(queue->ctrl);
1354 		return ret;
1355 	}
1356 	req = blk_mq_rq_to_pdu(rq);
1357 
1358 	req->status = cqe->status;
1359 	req->result = cqe->result;
1360 
1361 	if (wc->wc_flags & IB_WC_WITH_INVALIDATE) {
1362 		if (unlikely(wc->ex.invalidate_rkey != req->mr->rkey)) {
1363 			dev_err(queue->ctrl->ctrl.device,
1364 				"Bogus remote invalidation for rkey %#x\n",
1365 				req->mr->rkey);
1366 			nvme_rdma_error_recovery(queue->ctrl);
1367 		}
1368 	} else if (req->mr) {
1369 		ret = nvme_rdma_inv_rkey(queue, req);
1370 		if (unlikely(ret < 0)) {
1371 			dev_err(queue->ctrl->ctrl.device,
1372 				"Queueing INV WR for rkey %#x failed (%d)\n",
1373 				req->mr->rkey, ret);
1374 			nvme_rdma_error_recovery(queue->ctrl);
1375 		}
1376 		/* the local invalidation completion will end the request */
1377 		return 0;
1378 	}
1379 
1380 	if (refcount_dec_and_test(&req->ref)) {
1381 		if (rq->tag == tag)
1382 			ret = 1;
1383 		nvme_end_request(rq, req->status, req->result);
1384 	}
1385 
1386 	return ret;
1387 }
1388 
1389 static int __nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc, int tag)
1390 {
1391 	struct nvme_rdma_qe *qe =
1392 		container_of(wc->wr_cqe, struct nvme_rdma_qe, cqe);
1393 	struct nvme_rdma_queue *queue = cq->cq_context;
1394 	struct ib_device *ibdev = queue->device->dev;
1395 	struct nvme_completion *cqe = qe->data;
1396 	const size_t len = sizeof(struct nvme_completion);
1397 	int ret = 0;
1398 
1399 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1400 		nvme_rdma_wr_error(cq, wc, "RECV");
1401 		return 0;
1402 	}
1403 
1404 	ib_dma_sync_single_for_cpu(ibdev, qe->dma, len, DMA_FROM_DEVICE);
1405 	/*
1406 	 * AEN requests are special as they don't time out and can
1407 	 * survive any kind of queue freeze and often don't respond to
1408 	 * aborts.  We don't even bother to allocate a struct request
1409 	 * for them but rather special case them here.
1410 	 */
1411 	if (unlikely(nvme_rdma_queue_idx(queue) == 0 &&
1412 			cqe->command_id >= NVME_AQ_BLK_MQ_DEPTH))
1413 		nvme_complete_async_event(&queue->ctrl->ctrl, cqe->status,
1414 				&cqe->result);
1415 	else
1416 		ret = nvme_rdma_process_nvme_rsp(queue, cqe, wc, tag);
1417 	ib_dma_sync_single_for_device(ibdev, qe->dma, len, DMA_FROM_DEVICE);
1418 
1419 	nvme_rdma_post_recv(queue, qe);
1420 	return ret;
1421 }
1422 
1423 static void nvme_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc)
1424 {
1425 	__nvme_rdma_recv_done(cq, wc, -1);
1426 }
1427 
1428 static int nvme_rdma_conn_established(struct nvme_rdma_queue *queue)
1429 {
1430 	int ret, i;
1431 
1432 	for (i = 0; i < queue->queue_size; i++) {
1433 		ret = nvme_rdma_post_recv(queue, &queue->rsp_ring[i]);
1434 		if (ret)
1435 			goto out_destroy_queue_ib;
1436 	}
1437 
1438 	return 0;
1439 
1440 out_destroy_queue_ib:
1441 	nvme_rdma_destroy_queue_ib(queue);
1442 	return ret;
1443 }
1444 
1445 static int nvme_rdma_conn_rejected(struct nvme_rdma_queue *queue,
1446 		struct rdma_cm_event *ev)
1447 {
1448 	struct rdma_cm_id *cm_id = queue->cm_id;
1449 	int status = ev->status;
1450 	const char *rej_msg;
1451 	const struct nvme_rdma_cm_rej *rej_data;
1452 	u8 rej_data_len;
1453 
1454 	rej_msg = rdma_reject_msg(cm_id, status);
1455 	rej_data = rdma_consumer_reject_data(cm_id, ev, &rej_data_len);
1456 
1457 	if (rej_data && rej_data_len >= sizeof(u16)) {
1458 		u16 sts = le16_to_cpu(rej_data->sts);
1459 
1460 		dev_err(queue->ctrl->ctrl.device,
1461 		      "Connect rejected: status %d (%s) nvme status %d (%s).\n",
1462 		      status, rej_msg, sts, nvme_rdma_cm_msg(sts));
1463 	} else {
1464 		dev_err(queue->ctrl->ctrl.device,
1465 			"Connect rejected: status %d (%s).\n", status, rej_msg);
1466 	}
1467 
1468 	return -ECONNRESET;
1469 }
1470 
1471 static int nvme_rdma_addr_resolved(struct nvme_rdma_queue *queue)
1472 {
1473 	int ret;
1474 
1475 	ret = nvme_rdma_create_queue_ib(queue);
1476 	if (ret)
1477 		return ret;
1478 
1479 	ret = rdma_resolve_route(queue->cm_id, NVME_RDMA_CONNECT_TIMEOUT_MS);
1480 	if (ret) {
1481 		dev_err(queue->ctrl->ctrl.device,
1482 			"rdma_resolve_route failed (%d).\n",
1483 			queue->cm_error);
1484 		goto out_destroy_queue;
1485 	}
1486 
1487 	return 0;
1488 
1489 out_destroy_queue:
1490 	nvme_rdma_destroy_queue_ib(queue);
1491 	return ret;
1492 }
1493 
1494 static int nvme_rdma_route_resolved(struct nvme_rdma_queue *queue)
1495 {
1496 	struct nvme_rdma_ctrl *ctrl = queue->ctrl;
1497 	struct rdma_conn_param param = { };
1498 	struct nvme_rdma_cm_req priv = { };
1499 	int ret;
1500 
1501 	param.qp_num = queue->qp->qp_num;
1502 	param.flow_control = 1;
1503 
1504 	param.responder_resources = queue->device->dev->attrs.max_qp_rd_atom;
1505 	/* maximum retry count */
1506 	param.retry_count = 7;
1507 	param.rnr_retry_count = 7;
1508 	param.private_data = &priv;
1509 	param.private_data_len = sizeof(priv);
1510 
1511 	priv.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
1512 	priv.qid = cpu_to_le16(nvme_rdma_queue_idx(queue));
1513 	/*
1514 	 * set the admin queue depth to the minimum size
1515 	 * specified by the Fabrics standard.
1516 	 */
1517 	if (priv.qid == 0) {
1518 		priv.hrqsize = cpu_to_le16(NVME_AQ_DEPTH);
1519 		priv.hsqsize = cpu_to_le16(NVME_AQ_DEPTH - 1);
1520 	} else {
1521 		/*
1522 		 * current interpretation of the fabrics spec
1523 		 * is at minimum you make hrqsize sqsize+1, or a
1524 		 * 1's based representation of sqsize.
1525 		 */
1526 		priv.hrqsize = cpu_to_le16(queue->queue_size);
1527 		priv.hsqsize = cpu_to_le16(queue->ctrl->ctrl.sqsize);
1528 	}
1529 
1530 	ret = rdma_connect(queue->cm_id, &param);
1531 	if (ret) {
1532 		dev_err(ctrl->ctrl.device,
1533 			"rdma_connect failed (%d).\n", ret);
1534 		goto out_destroy_queue_ib;
1535 	}
1536 
1537 	return 0;
1538 
1539 out_destroy_queue_ib:
1540 	nvme_rdma_destroy_queue_ib(queue);
1541 	return ret;
1542 }
1543 
1544 static int nvme_rdma_cm_handler(struct rdma_cm_id *cm_id,
1545 		struct rdma_cm_event *ev)
1546 {
1547 	struct nvme_rdma_queue *queue = cm_id->context;
1548 	int cm_error = 0;
1549 
1550 	dev_dbg(queue->ctrl->ctrl.device, "%s (%d): status %d id %p\n",
1551 		rdma_event_msg(ev->event), ev->event,
1552 		ev->status, cm_id);
1553 
1554 	switch (ev->event) {
1555 	case RDMA_CM_EVENT_ADDR_RESOLVED:
1556 		cm_error = nvme_rdma_addr_resolved(queue);
1557 		break;
1558 	case RDMA_CM_EVENT_ROUTE_RESOLVED:
1559 		cm_error = nvme_rdma_route_resolved(queue);
1560 		break;
1561 	case RDMA_CM_EVENT_ESTABLISHED:
1562 		queue->cm_error = nvme_rdma_conn_established(queue);
1563 		/* complete cm_done regardless of success/failure */
1564 		complete(&queue->cm_done);
1565 		return 0;
1566 	case RDMA_CM_EVENT_REJECTED:
1567 		nvme_rdma_destroy_queue_ib(queue);
1568 		cm_error = nvme_rdma_conn_rejected(queue, ev);
1569 		break;
1570 	case RDMA_CM_EVENT_ROUTE_ERROR:
1571 	case RDMA_CM_EVENT_CONNECT_ERROR:
1572 	case RDMA_CM_EVENT_UNREACHABLE:
1573 		nvme_rdma_destroy_queue_ib(queue);
1574 	case RDMA_CM_EVENT_ADDR_ERROR:
1575 		dev_dbg(queue->ctrl->ctrl.device,
1576 			"CM error event %d\n", ev->event);
1577 		cm_error = -ECONNRESET;
1578 		break;
1579 	case RDMA_CM_EVENT_DISCONNECTED:
1580 	case RDMA_CM_EVENT_ADDR_CHANGE:
1581 	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
1582 		dev_dbg(queue->ctrl->ctrl.device,
1583 			"disconnect received - connection closed\n");
1584 		nvme_rdma_error_recovery(queue->ctrl);
1585 		break;
1586 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
1587 		/* device removal is handled via the ib_client API */
1588 		break;
1589 	default:
1590 		dev_err(queue->ctrl->ctrl.device,
1591 			"Unexpected RDMA CM event (%d)\n", ev->event);
1592 		nvme_rdma_error_recovery(queue->ctrl);
1593 		break;
1594 	}
1595 
1596 	if (cm_error) {
1597 		queue->cm_error = cm_error;
1598 		complete(&queue->cm_done);
1599 	}
1600 
1601 	return 0;
1602 }
1603 
1604 static enum blk_eh_timer_return
1605 nvme_rdma_timeout(struct request *rq, bool reserved)
1606 {
1607 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1608 
1609 	dev_warn(req->queue->ctrl->ctrl.device,
1610 		 "I/O %d QID %d timeout, reset controller\n",
1611 		 rq->tag, nvme_rdma_queue_idx(req->queue));
1612 
1613 	/* queue error recovery */
1614 	nvme_rdma_error_recovery(req->queue->ctrl);
1615 
1616 	/* fail with DNR on cmd timeout */
1617 	nvme_req(rq)->status = NVME_SC_ABORT_REQ | NVME_SC_DNR;
1618 
1619 	return BLK_EH_DONE;
1620 }
1621 
1622 static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
1623 		const struct blk_mq_queue_data *bd)
1624 {
1625 	struct nvme_ns *ns = hctx->queue->queuedata;
1626 	struct nvme_rdma_queue *queue = hctx->driver_data;
1627 	struct request *rq = bd->rq;
1628 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1629 	struct nvme_rdma_qe *sqe = &req->sqe;
1630 	struct nvme_command *c = sqe->data;
1631 	struct ib_device *dev;
1632 	bool queue_ready = test_bit(NVME_RDMA_Q_LIVE, &queue->flags);
1633 	blk_status_t ret;
1634 	int err;
1635 
1636 	WARN_ON_ONCE(rq->tag < 0);
1637 
1638 	if (!nvmf_check_ready(&queue->ctrl->ctrl, rq, queue_ready))
1639 		return nvmf_fail_nonready_command(rq);
1640 
1641 	dev = queue->device->dev;
1642 	ib_dma_sync_single_for_cpu(dev, sqe->dma,
1643 			sizeof(struct nvme_command), DMA_TO_DEVICE);
1644 
1645 	ret = nvme_setup_cmd(ns, rq, c);
1646 	if (ret)
1647 		return ret;
1648 
1649 	blk_mq_start_request(rq);
1650 
1651 	err = nvme_rdma_map_data(queue, rq, c);
1652 	if (unlikely(err < 0)) {
1653 		dev_err(queue->ctrl->ctrl.device,
1654 			     "Failed to map data (%d)\n", err);
1655 		nvme_cleanup_cmd(rq);
1656 		goto err;
1657 	}
1658 
1659 	sqe->cqe.done = nvme_rdma_send_done;
1660 
1661 	ib_dma_sync_single_for_device(dev, sqe->dma,
1662 			sizeof(struct nvme_command), DMA_TO_DEVICE);
1663 
1664 	err = nvme_rdma_post_send(queue, sqe, req->sge, req->num_sge,
1665 			req->mr ? &req->reg_wr.wr : NULL);
1666 	if (unlikely(err)) {
1667 		nvme_rdma_unmap_data(queue, rq);
1668 		goto err;
1669 	}
1670 
1671 	return BLK_STS_OK;
1672 err:
1673 	if (err == -ENOMEM || err == -EAGAIN)
1674 		return BLK_STS_RESOURCE;
1675 	return BLK_STS_IOERR;
1676 }
1677 
1678 static int nvme_rdma_poll(struct blk_mq_hw_ctx *hctx, unsigned int tag)
1679 {
1680 	struct nvme_rdma_queue *queue = hctx->driver_data;
1681 	struct ib_cq *cq = queue->ib_cq;
1682 	struct ib_wc wc;
1683 	int found = 0;
1684 
1685 	while (ib_poll_cq(cq, 1, &wc) > 0) {
1686 		struct ib_cqe *cqe = wc.wr_cqe;
1687 
1688 		if (cqe) {
1689 			if (cqe->done == nvme_rdma_recv_done)
1690 				found |= __nvme_rdma_recv_done(cq, &wc, tag);
1691 			else
1692 				cqe->done(cq, &wc);
1693 		}
1694 	}
1695 
1696 	return found;
1697 }
1698 
1699 static void nvme_rdma_complete_rq(struct request *rq)
1700 {
1701 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
1702 
1703 	nvme_rdma_unmap_data(req->queue, rq);
1704 	nvme_complete_rq(rq);
1705 }
1706 
1707 static int nvme_rdma_map_queues(struct blk_mq_tag_set *set)
1708 {
1709 	struct nvme_rdma_ctrl *ctrl = set->driver_data;
1710 
1711 	return blk_mq_rdma_map_queues(set, ctrl->device->dev, 0);
1712 }
1713 
1714 static const struct blk_mq_ops nvme_rdma_mq_ops = {
1715 	.queue_rq	= nvme_rdma_queue_rq,
1716 	.complete	= nvme_rdma_complete_rq,
1717 	.init_request	= nvme_rdma_init_request,
1718 	.exit_request	= nvme_rdma_exit_request,
1719 	.init_hctx	= nvme_rdma_init_hctx,
1720 	.poll		= nvme_rdma_poll,
1721 	.timeout	= nvme_rdma_timeout,
1722 	.map_queues	= nvme_rdma_map_queues,
1723 };
1724 
1725 static const struct blk_mq_ops nvme_rdma_admin_mq_ops = {
1726 	.queue_rq	= nvme_rdma_queue_rq,
1727 	.complete	= nvme_rdma_complete_rq,
1728 	.init_request	= nvme_rdma_init_request,
1729 	.exit_request	= nvme_rdma_exit_request,
1730 	.init_hctx	= nvme_rdma_init_admin_hctx,
1731 	.timeout	= nvme_rdma_timeout,
1732 };
1733 
1734 static void nvme_rdma_shutdown_ctrl(struct nvme_rdma_ctrl *ctrl, bool shutdown)
1735 {
1736 	if (ctrl->ctrl.queue_count > 1) {
1737 		nvme_stop_queues(&ctrl->ctrl);
1738 		nvme_rdma_stop_io_queues(ctrl);
1739 		blk_mq_tagset_busy_iter(&ctrl->tag_set,
1740 					nvme_cancel_request, &ctrl->ctrl);
1741 		nvme_rdma_destroy_io_queues(ctrl, shutdown);
1742 	}
1743 
1744 	if (shutdown)
1745 		nvme_shutdown_ctrl(&ctrl->ctrl);
1746 	else
1747 		nvme_disable_ctrl(&ctrl->ctrl, ctrl->ctrl.cap);
1748 
1749 	blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
1750 	nvme_rdma_stop_queue(&ctrl->queues[0]);
1751 	blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
1752 				nvme_cancel_request, &ctrl->ctrl);
1753 	blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
1754 	nvme_rdma_destroy_admin_queue(ctrl, shutdown);
1755 }
1756 
1757 static void nvme_rdma_delete_ctrl(struct nvme_ctrl *ctrl)
1758 {
1759 	nvme_rdma_shutdown_ctrl(to_rdma_ctrl(ctrl), true);
1760 }
1761 
1762 static void nvme_rdma_reset_ctrl_work(struct work_struct *work)
1763 {
1764 	struct nvme_rdma_ctrl *ctrl =
1765 		container_of(work, struct nvme_rdma_ctrl, ctrl.reset_work);
1766 	int ret;
1767 	bool changed;
1768 
1769 	nvme_stop_ctrl(&ctrl->ctrl);
1770 	nvme_rdma_shutdown_ctrl(ctrl, false);
1771 
1772 	if (!nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING)) {
1773 		/* state change failure should never happen */
1774 		WARN_ON_ONCE(1);
1775 		return;
1776 	}
1777 
1778 	ret = nvme_rdma_configure_admin_queue(ctrl, false);
1779 	if (ret)
1780 		goto out_fail;
1781 
1782 	if (ctrl->ctrl.queue_count > 1) {
1783 		ret = nvme_rdma_configure_io_queues(ctrl, false);
1784 		if (ret)
1785 			goto out_fail;
1786 	}
1787 
1788 	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
1789 	if (!changed) {
1790 		/* state change failure is ok if we're in DELETING state */
1791 		WARN_ON_ONCE(ctrl->ctrl.state != NVME_CTRL_DELETING);
1792 		return;
1793 	}
1794 
1795 	nvme_start_ctrl(&ctrl->ctrl);
1796 
1797 	return;
1798 
1799 out_fail:
1800 	++ctrl->ctrl.nr_reconnects;
1801 	nvme_rdma_reconnect_or_remove(ctrl);
1802 }
1803 
1804 static const struct nvme_ctrl_ops nvme_rdma_ctrl_ops = {
1805 	.name			= "rdma",
1806 	.module			= THIS_MODULE,
1807 	.flags			= NVME_F_FABRICS,
1808 	.reg_read32		= nvmf_reg_read32,
1809 	.reg_read64		= nvmf_reg_read64,
1810 	.reg_write32		= nvmf_reg_write32,
1811 	.free_ctrl		= nvme_rdma_free_ctrl,
1812 	.submit_async_event	= nvme_rdma_submit_async_event,
1813 	.delete_ctrl		= nvme_rdma_delete_ctrl,
1814 	.get_address		= nvmf_get_address,
1815 	.stop_ctrl		= nvme_rdma_stop_ctrl,
1816 };
1817 
1818 static inline bool
1819 __nvme_rdma_options_match(struct nvme_rdma_ctrl *ctrl,
1820 	struct nvmf_ctrl_options *opts)
1821 {
1822 	char *stdport = __stringify(NVME_RDMA_IP_PORT);
1823 
1824 
1825 	if (!nvmf_ctlr_matches_baseopts(&ctrl->ctrl, opts) ||
1826 	    strcmp(opts->traddr, ctrl->ctrl.opts->traddr))
1827 		return false;
1828 
1829 	if (opts->mask & NVMF_OPT_TRSVCID &&
1830 	    ctrl->ctrl.opts->mask & NVMF_OPT_TRSVCID) {
1831 		if (strcmp(opts->trsvcid, ctrl->ctrl.opts->trsvcid))
1832 			return false;
1833 	} else if (opts->mask & NVMF_OPT_TRSVCID) {
1834 		if (strcmp(opts->trsvcid, stdport))
1835 			return false;
1836 	} else if (ctrl->ctrl.opts->mask & NVMF_OPT_TRSVCID) {
1837 		if (strcmp(stdport, ctrl->ctrl.opts->trsvcid))
1838 			return false;
1839 	}
1840 	/* else, it's a match as both have stdport. Fall to next checks */
1841 
1842 	/*
1843 	 * checking the local address is rough. In most cases, one
1844 	 * is not specified and the host port is selected by the stack.
1845 	 *
1846 	 * Assume no match if:
1847 	 *  local address is specified and address is not the same
1848 	 *  local address is not specified but remote is, or vice versa
1849 	 *    (admin using specific host_traddr when it matters).
1850 	 */
1851 	if (opts->mask & NVMF_OPT_HOST_TRADDR &&
1852 	    ctrl->ctrl.opts->mask & NVMF_OPT_HOST_TRADDR) {
1853 		if (strcmp(opts->host_traddr, ctrl->ctrl.opts->host_traddr))
1854 			return false;
1855 	} else if (opts->mask & NVMF_OPT_HOST_TRADDR ||
1856 		   ctrl->ctrl.opts->mask & NVMF_OPT_HOST_TRADDR)
1857 		return false;
1858 	/*
1859 	 * if neither controller had an host port specified, assume it's
1860 	 * a match as everything else matched.
1861 	 */
1862 
1863 	return true;
1864 }
1865 
1866 /*
1867  * Fails a connection request if it matches an existing controller
1868  * (association) with the same tuple:
1869  * <Host NQN, Host ID, local address, remote address, remote port, SUBSYS NQN>
1870  *
1871  * if local address is not specified in the request, it will match an
1872  * existing controller with all the other parameters the same and no
1873  * local port address specified as well.
1874  *
1875  * The ports don't need to be compared as they are intrinsically
1876  * already matched by the port pointers supplied.
1877  */
1878 static bool
1879 nvme_rdma_existing_controller(struct nvmf_ctrl_options *opts)
1880 {
1881 	struct nvme_rdma_ctrl *ctrl;
1882 	bool found = false;
1883 
1884 	mutex_lock(&nvme_rdma_ctrl_mutex);
1885 	list_for_each_entry(ctrl, &nvme_rdma_ctrl_list, list) {
1886 		found = __nvme_rdma_options_match(ctrl, opts);
1887 		if (found)
1888 			break;
1889 	}
1890 	mutex_unlock(&nvme_rdma_ctrl_mutex);
1891 
1892 	return found;
1893 }
1894 
1895 static struct nvme_ctrl *nvme_rdma_create_ctrl(struct device *dev,
1896 		struct nvmf_ctrl_options *opts)
1897 {
1898 	struct nvme_rdma_ctrl *ctrl;
1899 	int ret;
1900 	bool changed;
1901 	char *port;
1902 
1903 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
1904 	if (!ctrl)
1905 		return ERR_PTR(-ENOMEM);
1906 	ctrl->ctrl.opts = opts;
1907 	INIT_LIST_HEAD(&ctrl->list);
1908 
1909 	if (opts->mask & NVMF_OPT_TRSVCID)
1910 		port = opts->trsvcid;
1911 	else
1912 		port = __stringify(NVME_RDMA_IP_PORT);
1913 
1914 	ret = inet_pton_with_scope(&init_net, AF_UNSPEC,
1915 			opts->traddr, port, &ctrl->addr);
1916 	if (ret) {
1917 		pr_err("malformed address passed: %s:%s\n", opts->traddr, port);
1918 		goto out_free_ctrl;
1919 	}
1920 
1921 	if (opts->mask & NVMF_OPT_HOST_TRADDR) {
1922 		ret = inet_pton_with_scope(&init_net, AF_UNSPEC,
1923 			opts->host_traddr, NULL, &ctrl->src_addr);
1924 		if (ret) {
1925 			pr_err("malformed src address passed: %s\n",
1926 			       opts->host_traddr);
1927 			goto out_free_ctrl;
1928 		}
1929 	}
1930 
1931 	if (!opts->duplicate_connect && nvme_rdma_existing_controller(opts)) {
1932 		ret = -EALREADY;
1933 		goto out_free_ctrl;
1934 	}
1935 
1936 	INIT_DELAYED_WORK(&ctrl->reconnect_work,
1937 			nvme_rdma_reconnect_ctrl_work);
1938 	INIT_WORK(&ctrl->err_work, nvme_rdma_error_recovery_work);
1939 	INIT_WORK(&ctrl->ctrl.reset_work, nvme_rdma_reset_ctrl_work);
1940 
1941 	ctrl->ctrl.queue_count = opts->nr_io_queues + 1; /* +1 for admin queue */
1942 	ctrl->ctrl.sqsize = opts->queue_size - 1;
1943 	ctrl->ctrl.kato = opts->kato;
1944 
1945 	ret = -ENOMEM;
1946 	ctrl->queues = kcalloc(ctrl->ctrl.queue_count, sizeof(*ctrl->queues),
1947 				GFP_KERNEL);
1948 	if (!ctrl->queues)
1949 		goto out_free_ctrl;
1950 
1951 	ret = nvme_init_ctrl(&ctrl->ctrl, dev, &nvme_rdma_ctrl_ops,
1952 				0 /* no quirks, we're perfect! */);
1953 	if (ret)
1954 		goto out_kfree_queues;
1955 
1956 	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING);
1957 	WARN_ON_ONCE(!changed);
1958 
1959 	ret = nvme_rdma_configure_admin_queue(ctrl, true);
1960 	if (ret)
1961 		goto out_uninit_ctrl;
1962 
1963 	/* sanity check icdoff */
1964 	if (ctrl->ctrl.icdoff) {
1965 		dev_err(ctrl->ctrl.device, "icdoff is not supported!\n");
1966 		ret = -EINVAL;
1967 		goto out_remove_admin_queue;
1968 	}
1969 
1970 	/* sanity check keyed sgls */
1971 	if (!(ctrl->ctrl.sgls & (1 << 2))) {
1972 		dev_err(ctrl->ctrl.device,
1973 			"Mandatory keyed sgls are not supported!\n");
1974 		ret = -EINVAL;
1975 		goto out_remove_admin_queue;
1976 	}
1977 
1978 	/* only warn if argument is too large here, will clamp later */
1979 	if (opts->queue_size > ctrl->ctrl.sqsize + 1) {
1980 		dev_warn(ctrl->ctrl.device,
1981 			"queue_size %zu > ctrl sqsize %u, clamping down\n",
1982 			opts->queue_size, ctrl->ctrl.sqsize + 1);
1983 	}
1984 
1985 	/* warn if maxcmd is lower than sqsize+1 */
1986 	if (ctrl->ctrl.sqsize + 1 > ctrl->ctrl.maxcmd) {
1987 		dev_warn(ctrl->ctrl.device,
1988 			"sqsize %u > ctrl maxcmd %u, clamping down\n",
1989 			ctrl->ctrl.sqsize + 1, ctrl->ctrl.maxcmd);
1990 		ctrl->ctrl.sqsize = ctrl->ctrl.maxcmd - 1;
1991 	}
1992 
1993 	if (opts->nr_io_queues) {
1994 		ret = nvme_rdma_configure_io_queues(ctrl, true);
1995 		if (ret)
1996 			goto out_remove_admin_queue;
1997 	}
1998 
1999 	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);
2000 	WARN_ON_ONCE(!changed);
2001 
2002 	dev_info(ctrl->ctrl.device, "new ctrl: NQN \"%s\", addr %pISpcs\n",
2003 		ctrl->ctrl.opts->subsysnqn, &ctrl->addr);
2004 
2005 	nvme_get_ctrl(&ctrl->ctrl);
2006 
2007 	mutex_lock(&nvme_rdma_ctrl_mutex);
2008 	list_add_tail(&ctrl->list, &nvme_rdma_ctrl_list);
2009 	mutex_unlock(&nvme_rdma_ctrl_mutex);
2010 
2011 	nvme_start_ctrl(&ctrl->ctrl);
2012 
2013 	return &ctrl->ctrl;
2014 
2015 out_remove_admin_queue:
2016 	nvme_rdma_stop_queue(&ctrl->queues[0]);
2017 	nvme_rdma_destroy_admin_queue(ctrl, true);
2018 out_uninit_ctrl:
2019 	nvme_uninit_ctrl(&ctrl->ctrl);
2020 	nvme_put_ctrl(&ctrl->ctrl);
2021 	if (ret > 0)
2022 		ret = -EIO;
2023 	return ERR_PTR(ret);
2024 out_kfree_queues:
2025 	kfree(ctrl->queues);
2026 out_free_ctrl:
2027 	kfree(ctrl);
2028 	return ERR_PTR(ret);
2029 }
2030 
2031 static struct nvmf_transport_ops nvme_rdma_transport = {
2032 	.name		= "rdma",
2033 	.module		= THIS_MODULE,
2034 	.required_opts	= NVMF_OPT_TRADDR,
2035 	.allowed_opts	= NVMF_OPT_TRSVCID | NVMF_OPT_RECONNECT_DELAY |
2036 			  NVMF_OPT_HOST_TRADDR | NVMF_OPT_CTRL_LOSS_TMO,
2037 	.create_ctrl	= nvme_rdma_create_ctrl,
2038 };
2039 
2040 static void nvme_rdma_remove_one(struct ib_device *ib_device, void *client_data)
2041 {
2042 	struct nvme_rdma_ctrl *ctrl;
2043 	struct nvme_rdma_device *ndev;
2044 	bool found = false;
2045 
2046 	mutex_lock(&device_list_mutex);
2047 	list_for_each_entry(ndev, &device_list, entry) {
2048 		if (ndev->dev == ib_device) {
2049 			found = true;
2050 			break;
2051 		}
2052 	}
2053 	mutex_unlock(&device_list_mutex);
2054 
2055 	if (!found)
2056 		return;
2057 
2058 	/* Delete all controllers using this device */
2059 	mutex_lock(&nvme_rdma_ctrl_mutex);
2060 	list_for_each_entry(ctrl, &nvme_rdma_ctrl_list, list) {
2061 		if (ctrl->device->dev != ib_device)
2062 			continue;
2063 		nvme_delete_ctrl(&ctrl->ctrl);
2064 	}
2065 	mutex_unlock(&nvme_rdma_ctrl_mutex);
2066 
2067 	flush_workqueue(nvme_delete_wq);
2068 }
2069 
2070 static struct ib_client nvme_rdma_ib_client = {
2071 	.name   = "nvme_rdma",
2072 	.remove = nvme_rdma_remove_one
2073 };
2074 
2075 static int __init nvme_rdma_init_module(void)
2076 {
2077 	int ret;
2078 
2079 	ret = ib_register_client(&nvme_rdma_ib_client);
2080 	if (ret)
2081 		return ret;
2082 
2083 	ret = nvmf_register_transport(&nvme_rdma_transport);
2084 	if (ret)
2085 		goto err_unreg_client;
2086 
2087 	return 0;
2088 
2089 err_unreg_client:
2090 	ib_unregister_client(&nvme_rdma_ib_client);
2091 	return ret;
2092 }
2093 
2094 static void __exit nvme_rdma_cleanup_module(void)
2095 {
2096 	nvmf_unregister_transport(&nvme_rdma_transport);
2097 	ib_unregister_client(&nvme_rdma_ib_client);
2098 }
2099 
2100 module_init(nvme_rdma_init_module);
2101 module_exit(nvme_rdma_cleanup_module);
2102 
2103 MODULE_LICENSE("GPL v2");
2104