rdma.c 40.6 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
/*
 * NVMe over Fabrics RDMA target.
 * Copyright (c) 2015-2016 HGST, a Western Digital Company.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/atomic.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/nvme.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/wait.h>
#include <linux/inet.h>
#include <asm/unaligned.h>

#include <rdma/ib_verbs.h>
#include <rdma/rdma_cm.h>
#include <rdma/rw.h>

#include <linux/nvme-rdma.h>
#include "nvmet.h"

/*
36
 * We allow at least 1 page, up to 4 SGEs, and up to 16KB of inline data
37
 */
38
39
40
#define NVMET_RDMA_DEFAULT_INLINE_DATA_SIZE	PAGE_SIZE
#define NVMET_RDMA_MAX_INLINE_SGE		4
#define NVMET_RDMA_MAX_INLINE_DATA_SIZE		max_t(int, SZ_16K, PAGE_SIZE)
41
42

struct nvmet_rdma_cmd {
43
	struct ib_sge		sge[NVMET_RDMA_MAX_INLINE_SGE + 1];
44
45
	struct ib_cqe		cqe;
	struct ib_recv_wr	wr;
46
	struct scatterlist	inline_sg[NVMET_RDMA_MAX_INLINE_SGE];
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
	struct nvme_command     *nvme_cmd;
	struct nvmet_rdma_queue	*queue;
};

enum {
	NVMET_RDMA_REQ_INLINE_DATA	= (1 << 0),
	NVMET_RDMA_REQ_INVALIDATE_RKEY	= (1 << 1),
};

struct nvmet_rdma_rsp {
	struct ib_sge		send_sge;
	struct ib_cqe		send_cqe;
	struct ib_send_wr	send_wr;

	struct nvmet_rdma_cmd	*cmd;
	struct nvmet_rdma_queue	*queue;

	struct ib_cqe		read_cqe;
	struct rdma_rw_ctx	rw;

	struct nvmet_req	req;

69
	bool			allocated;
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
	u8			n_rdma;
	u32			flags;
	u32			invalidate_rkey;

	struct list_head	wait_list;
	struct list_head	free_list;
};

enum nvmet_rdma_queue_state {
	NVMET_RDMA_Q_CONNECTING,
	NVMET_RDMA_Q_LIVE,
	NVMET_RDMA_Q_DISCONNECTING,
};

struct nvmet_rdma_queue {
	struct rdma_cm_id	*cm_id;
	struct nvmet_port	*port;
	struct ib_cq		*cq;
	atomic_t		sq_wr_avail;
	struct nvmet_rdma_device *dev;
	spinlock_t		state_lock;
	enum nvmet_rdma_queue_state state;
	struct nvmet_cq		nvme_cq;
	struct nvmet_sq		nvme_sq;

	struct nvmet_rdma_rsp	*rsps;
	struct list_head	free_rsps;
	spinlock_t		rsps_lock;
	struct nvmet_rdma_cmd	*cmds;

	struct work_struct	release_work;
	struct list_head	rsp_wait_list;
	struct list_head	rsp_wr_wait_list;
	spinlock_t		rsp_wr_wait_lock;

	int			idx;
	int			host_qid;
	int			recv_queue_size;
	int			send_queue_size;

	struct list_head	queue_list;
};

struct nvmet_rdma_device {
	struct ib_device	*device;
	struct ib_pd		*pd;
	struct ib_srq		*srq;
	struct nvmet_rdma_cmd	*srq_cmds;
	size_t			srq_size;
	struct kref		ref;
	struct list_head	entry;
121
122
	int			inline_data_size;
	int			inline_page_count;
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
};

static bool nvmet_rdma_use_srq;
module_param_named(use_srq, nvmet_rdma_use_srq, bool, 0444);
MODULE_PARM_DESC(use_srq, "Use shared receive queue.");

static DEFINE_IDA(nvmet_rdma_queue_ida);
static LIST_HEAD(nvmet_rdma_queue_list);
static DEFINE_MUTEX(nvmet_rdma_queue_mutex);

static LIST_HEAD(device_list);
static DEFINE_MUTEX(device_list_mutex);

static bool nvmet_rdma_execute_command(struct nvmet_rdma_rsp *rsp);
static void nvmet_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc);
static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc);
static void nvmet_rdma_read_data_done(struct ib_cq *cq, struct ib_wc *wc);
static void nvmet_rdma_qp_event(struct ib_event *event, void *priv);
static void nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue);

143
static const struct nvmet_fabrics_ops nvmet_rdma_ops;
144

145
146
147
148
149
static int num_pages(int len)
{
	return 1 + (((len - 1) & PAGE_MASK) >> PAGE_SHIFT);
}

150
151
152
153
154
155
156
157
158
/* XXX: really should move to a generic header sooner or later.. */
static inline u32 get_unaligned_le24(const u8 *p)
{
	return (u32)p[0] | (u32)p[1] << 8 | (u32)p[2] << 16;
}

static inline bool nvmet_rdma_need_data_in(struct nvmet_rdma_rsp *rsp)
{
	return nvme_is_write(rsp->req.cmd) &&
159
		rsp->req.transfer_len &&
160
161
162
163
164
165
		!(rsp->flags & NVMET_RDMA_REQ_INLINE_DATA);
}

static inline bool nvmet_rdma_need_data_out(struct nvmet_rdma_rsp *rsp)
{
	return !nvme_is_write(rsp->req.cmd) &&
166
		rsp->req.transfer_len &&
167
168
169
170
171
172
173
174
175
176
177
		!rsp->req.rsp->status &&
		!(rsp->flags & NVMET_RDMA_REQ_INLINE_DATA);
}

static inline struct nvmet_rdma_rsp *
nvmet_rdma_get_rsp(struct nvmet_rdma_queue *queue)
{
	struct nvmet_rdma_rsp *rsp;
	unsigned long flags;

	spin_lock_irqsave(&queue->rsps_lock, flags);
178
	rsp = list_first_entry_or_null(&queue->free_rsps,
179
				struct nvmet_rdma_rsp, free_list);
180
181
	if (likely(rsp))
		list_del(&rsp->free_list);
182
183
	spin_unlock_irqrestore(&queue->rsps_lock, flags);

184
185
186
187
188
189
190
	if (unlikely(!rsp)) {
		rsp = kmalloc(sizeof(*rsp), GFP_KERNEL);
		if (unlikely(!rsp))
			return NULL;
		rsp->allocated = true;
	}

191
192
193
194
195
196
197
198
	return rsp;
}

static inline void
nvmet_rdma_put_rsp(struct nvmet_rdma_rsp *rsp)
{
	unsigned long flags;

199
200
201
202
203
	if (rsp->allocated) {
		kfree(rsp);
		return;
	}

204
205
206
207
208
	spin_lock_irqsave(&rsp->queue->rsps_lock, flags);
	list_add_tail(&rsp->free_list, &rsp->queue->free_rsps);
	spin_unlock_irqrestore(&rsp->queue->rsps_lock, flags);
}

209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
static void nvmet_rdma_free_inline_pages(struct nvmet_rdma_device *ndev,
				struct nvmet_rdma_cmd *c)
{
	struct scatterlist *sg;
	struct ib_sge *sge;
	int i;

	if (!ndev->inline_data_size)
		return;

	sg = c->inline_sg;
	sge = &c->sge[1];

	for (i = 0; i < ndev->inline_page_count; i++, sg++, sge++) {
		if (sge->length)
			ib_dma_unmap_page(ndev->device, sge->addr,
					sge->length, DMA_FROM_DEVICE);
		if (sg_page(sg))
			__free_page(sg_page(sg));
	}
}

static int nvmet_rdma_alloc_inline_pages(struct nvmet_rdma_device *ndev,
				struct nvmet_rdma_cmd *c)
{
	struct scatterlist *sg;
	struct ib_sge *sge;
	struct page *pg;
	int len;
	int i;

	if (!ndev->inline_data_size)
		return 0;

	sg = c->inline_sg;
	sg_init_table(sg, ndev->inline_page_count);
	sge = &c->sge[1];
	len = ndev->inline_data_size;

	for (i = 0; i < ndev->inline_page_count; i++, sg++, sge++) {
		pg = alloc_page(GFP_KERNEL);
		if (!pg)
			goto out_err;
		sg_assign_page(sg, pg);
		sge->addr = ib_dma_map_page(ndev->device,
			pg, 0, PAGE_SIZE, DMA_FROM_DEVICE);
		if (ib_dma_mapping_error(ndev->device, sge->addr))
			goto out_err;
		sge->length = min_t(int, len, PAGE_SIZE);
		sge->lkey = ndev->pd->local_dma_lkey;
		len -= sge->length;
	}

	return 0;
out_err:
	for (; i >= 0; i--, sg--, sge--) {
		if (sge->length)
			ib_dma_unmap_page(ndev->device, sge->addr,
					sge->length, DMA_FROM_DEVICE);
		if (sg_page(sg))
			__free_page(sg_page(sg));
	}
	return -ENOMEM;
}

274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
static int nvmet_rdma_alloc_cmd(struct nvmet_rdma_device *ndev,
			struct nvmet_rdma_cmd *c, bool admin)
{
	/* NVMe command / RDMA RECV */
	c->nvme_cmd = kmalloc(sizeof(*c->nvme_cmd), GFP_KERNEL);
	if (!c->nvme_cmd)
		goto out;

	c->sge[0].addr = ib_dma_map_single(ndev->device, c->nvme_cmd,
			sizeof(*c->nvme_cmd), DMA_FROM_DEVICE);
	if (ib_dma_mapping_error(ndev->device, c->sge[0].addr))
		goto out_free_cmd;

	c->sge[0].length = sizeof(*c->nvme_cmd);
	c->sge[0].lkey = ndev->pd->local_dma_lkey;

290
291
	if (!admin && nvmet_rdma_alloc_inline_pages(ndev, c))
		goto out_unmap_cmd;
292
293
294
295
296

	c->cqe.done = nvmet_rdma_recv_done;

	c->wr.wr_cqe = &c->cqe;
	c->wr.sg_list = c->sge;
297
	c->wr.num_sge = admin ? 1 : ndev->inline_page_count + 1;
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313

	return 0;

out_unmap_cmd:
	ib_dma_unmap_single(ndev->device, c->sge[0].addr,
			sizeof(*c->nvme_cmd), DMA_FROM_DEVICE);
out_free_cmd:
	kfree(c->nvme_cmd);

out:
	return -ENOMEM;
}

static void nvmet_rdma_free_cmd(struct nvmet_rdma_device *ndev,
		struct nvmet_rdma_cmd *c, bool admin)
{
314
315
	if (!admin)
		nvmet_rdma_free_inline_pages(ndev, c);
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
	ib_dma_unmap_single(ndev->device, c->sge[0].addr,
				sizeof(*c->nvme_cmd), DMA_FROM_DEVICE);
	kfree(c->nvme_cmd);
}

static struct nvmet_rdma_cmd *
nvmet_rdma_alloc_cmds(struct nvmet_rdma_device *ndev,
		int nr_cmds, bool admin)
{
	struct nvmet_rdma_cmd *cmds;
	int ret = -EINVAL, i;

	cmds = kcalloc(nr_cmds, sizeof(struct nvmet_rdma_cmd), GFP_KERNEL);
	if (!cmds)
		goto out;

	for (i = 0; i < nr_cmds; i++) {
		ret = nvmet_rdma_alloc_cmd(ndev, cmds + i, admin);
		if (ret)
			goto out_free;
	}

	return cmds;

out_free:
	while (--i >= 0)
		nvmet_rdma_free_cmd(ndev, cmds + i, admin);
	kfree(cmds);
out:
	return ERR_PTR(ret);
}

static void nvmet_rdma_free_cmds(struct nvmet_rdma_device *ndev,
		struct nvmet_rdma_cmd *cmds, int nr_cmds, bool admin)
{
	int i;

	for (i = 0; i < nr_cmds; i++)
		nvmet_rdma_free_cmd(ndev, cmds + i, admin);
	kfree(cmds);
}

static int nvmet_rdma_alloc_rsp(struct nvmet_rdma_device *ndev,
		struct nvmet_rdma_rsp *r)
{
	/* NVMe CQE / RDMA SEND */
	r->req.rsp = kmalloc(sizeof(*r->req.rsp), GFP_KERNEL);
	if (!r->req.rsp)
		goto out;

	r->send_sge.addr = ib_dma_map_single(ndev->device, r->req.rsp,
			sizeof(*r->req.rsp), DMA_TO_DEVICE);
	if (ib_dma_mapping_error(ndev->device, r->send_sge.addr))
		goto out_free_rsp;

	r->send_sge.length = sizeof(*r->req.rsp);
	r->send_sge.lkey = ndev->pd->local_dma_lkey;

	r->send_cqe.done = nvmet_rdma_send_done;

	r->send_wr.wr_cqe = &r->send_cqe;
	r->send_wr.sg_list = &r->send_sge;
	r->send_wr.num_sge = 1;
	r->send_wr.send_flags = IB_SEND_SIGNALED;

	/* Data In / RDMA READ */
	r->read_cqe.done = nvmet_rdma_read_data_done;
	return 0;

out_free_rsp:
	kfree(r->req.rsp);
out:
	return -ENOMEM;
}

static void nvmet_rdma_free_rsp(struct nvmet_rdma_device *ndev,
		struct nvmet_rdma_rsp *r)
{
	ib_dma_unmap_single(ndev->device, r->send_sge.addr,
				sizeof(*r->req.rsp), DMA_TO_DEVICE);
	kfree(r->req.rsp);
}

static int
nvmet_rdma_alloc_rsps(struct nvmet_rdma_queue *queue)
{
	struct nvmet_rdma_device *ndev = queue->dev;
	int nr_rsps = queue->recv_queue_size * 2;
	int ret = -EINVAL, i;

	queue->rsps = kcalloc(nr_rsps, sizeof(struct nvmet_rdma_rsp),
			GFP_KERNEL);
	if (!queue->rsps)
		goto out;

	for (i = 0; i < nr_rsps; i++) {
		struct nvmet_rdma_rsp *rsp = &queue->rsps[i];

		ret = nvmet_rdma_alloc_rsp(ndev, rsp);
		if (ret)
			goto out_free;

		list_add_tail(&rsp->free_list, &queue->free_rsps);
	}

	return 0;

out_free:
	while (--i >= 0) {
		struct nvmet_rdma_rsp *rsp = &queue->rsps[i];

		list_del(&rsp->free_list);
		nvmet_rdma_free_rsp(ndev, rsp);
	}
	kfree(queue->rsps);
out:
	return ret;
}

static void nvmet_rdma_free_rsps(struct nvmet_rdma_queue *queue)
{
	struct nvmet_rdma_device *ndev = queue->dev;
	int i, nr_rsps = queue->recv_queue_size * 2;

	for (i = 0; i < nr_rsps; i++) {
		struct nvmet_rdma_rsp *rsp = &queue->rsps[i];

		list_del(&rsp->free_list);
		nvmet_rdma_free_rsp(ndev, rsp);
	}
	kfree(queue->rsps);
}

static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev,
		struct nvmet_rdma_cmd *cmd)
{
452
	int ret;
453

454
455
456
457
	ib_dma_sync_single_for_device(ndev->device,
		cmd->sge[0].addr, cmd->sge[0].length,
		DMA_FROM_DEVICE);

458
	if (ndev->srq)
459
		ret = ib_post_srq_recv(ndev->srq, &cmd->wr, NULL);
460
	else
461
		ret = ib_post_recv(cmd->queue->cm_id->qp, &cmd->wr, NULL);
462
463
464
465
466

	if (unlikely(ret))
		pr_err("post_recv cmd failed\n");

	return ret;
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
}

static void nvmet_rdma_process_wr_wait_list(struct nvmet_rdma_queue *queue)
{
	spin_lock(&queue->rsp_wr_wait_lock);
	while (!list_empty(&queue->rsp_wr_wait_list)) {
		struct nvmet_rdma_rsp *rsp;
		bool ret;

		rsp = list_entry(queue->rsp_wr_wait_list.next,
				struct nvmet_rdma_rsp, wait_list);
		list_del(&rsp->wait_list);

		spin_unlock(&queue->rsp_wr_wait_lock);
		ret = nvmet_rdma_execute_command(rsp);
		spin_lock(&queue->rsp_wr_wait_lock);

		if (!ret) {
			list_add(&rsp->wait_list, &queue->rsp_wr_wait_list);
			break;
		}
	}
	spin_unlock(&queue->rsp_wr_wait_lock);
}


static void nvmet_rdma_release_rsp(struct nvmet_rdma_rsp *rsp)
{
	struct nvmet_rdma_queue *queue = rsp->queue;

	atomic_add(1 + rsp->n_rdma, &queue->sq_wr_avail);

	if (rsp->n_rdma) {
		rdma_rw_ctx_destroy(&rsp->rw, queue->cm_id->qp,
				queue->cm_id->port_num, rsp->req.sg,
				rsp->req.sg_cnt, nvmet_data_dir(&rsp->req));
	}

505
	if (rsp->req.sg != rsp->cmd->inline_sg)
506
		nvmet_req_free_sgl(&rsp->req);
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531

	if (unlikely(!list_empty_careful(&queue->rsp_wr_wait_list)))
		nvmet_rdma_process_wr_wait_list(queue);

	nvmet_rdma_put_rsp(rsp);
}

static void nvmet_rdma_error_comp(struct nvmet_rdma_queue *queue)
{
	if (queue->nvme_sq.ctrl) {
		nvmet_ctrl_fatal_error(queue->nvme_sq.ctrl);
	} else {
		/*
		 * we didn't setup the controller yet in case
		 * of admin connect error, just disconnect and
		 * cleanup the queue
		 */
		nvmet_rdma_queue_disconnect(queue);
	}
}

static void nvmet_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc)
{
	struct nvmet_rdma_rsp *rsp =
		container_of(wc->wr_cqe, struct nvmet_rdma_rsp, send_cqe);
532
	struct nvmet_rdma_queue *queue = cq->cq_context;
533
534
535
536
537
538
539

	nvmet_rdma_release_rsp(rsp);

	if (unlikely(wc->status != IB_WC_SUCCESS &&
		     wc->status != IB_WC_WR_FLUSH_ERR)) {
		pr_err("SEND for CQE 0x%p failed with status %s (%d).\n",
			wc->wr_cqe, ib_wc_status_msg(wc->status), wc->status);
540
		nvmet_rdma_error_comp(queue);
541
542
543
544
545
546
547
548
	}
}

static void nvmet_rdma_queue_response(struct nvmet_req *req)
{
	struct nvmet_rdma_rsp *rsp =
		container_of(req, struct nvmet_rdma_rsp, req);
	struct rdma_cm_id *cm_id = rsp->queue->cm_id;
549
	struct ib_send_wr *first_wr;
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564

	if (rsp->flags & NVMET_RDMA_REQ_INVALIDATE_RKEY) {
		rsp->send_wr.opcode = IB_WR_SEND_WITH_INV;
		rsp->send_wr.ex.invalidate_rkey = rsp->invalidate_rkey;
	} else {
		rsp->send_wr.opcode = IB_WR_SEND;
	}

	if (nvmet_rdma_need_data_out(rsp))
		first_wr = rdma_rw_ctx_wrs(&rsp->rw, cm_id->qp,
				cm_id->port_num, NULL, &rsp->send_wr);
	else
		first_wr = &rsp->send_wr;

	nvmet_rdma_post_recv(rsp->queue->dev, rsp->cmd);
565
566
567
568
569

	ib_dma_sync_single_for_device(rsp->queue->dev->device,
		rsp->send_sge.addr, rsp->send_sge.length,
		DMA_TO_DEVICE);

570
	if (unlikely(ib_post_send(cm_id->qp, first_wr, NULL))) {
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
		pr_err("sending cmd response failed\n");
		nvmet_rdma_release_rsp(rsp);
	}
}

static void nvmet_rdma_read_data_done(struct ib_cq *cq, struct ib_wc *wc)
{
	struct nvmet_rdma_rsp *rsp =
		container_of(wc->wr_cqe, struct nvmet_rdma_rsp, read_cqe);
	struct nvmet_rdma_queue *queue = cq->cq_context;

	WARN_ON(rsp->n_rdma <= 0);
	atomic_add(rsp->n_rdma, &queue->sq_wr_avail);
	rdma_rw_ctx_destroy(&rsp->rw, queue->cm_id->qp,
			queue->cm_id->port_num, rsp->req.sg,
			rsp->req.sg_cnt, nvmet_data_dir(&rsp->req));
	rsp->n_rdma = 0;

	if (unlikely(wc->status != IB_WC_SUCCESS)) {
590
		nvmet_req_uninit(&rsp->req);
591
592
593
594
595
596
597
598
599
		nvmet_rdma_release_rsp(rsp);
		if (wc->status != IB_WC_WR_FLUSH_ERR) {
			pr_info("RDMA READ for CQE 0x%p failed with status %s (%d).\n",
				wc->wr_cqe, ib_wc_status_msg(wc->status), wc->status);
			nvmet_rdma_error_comp(queue);
		}
		return;
	}

600
	nvmet_req_execute(&rsp->req);
601
602
603
604
605
}

static void nvmet_rdma_use_inline_sg(struct nvmet_rdma_rsp *rsp, u32 len,
		u64 off)
{
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
	int sg_count = num_pages(len);
	struct scatterlist *sg;
	int i;

	sg = rsp->cmd->inline_sg;
	for (i = 0; i < sg_count; i++, sg++) {
		if (i < sg_count - 1)
			sg_unmark_end(sg);
		else
			sg_mark_end(sg);
		sg->offset = off;
		sg->length = min_t(int, len, PAGE_SIZE - off);
		len -= sg->length;
		if (!i)
			off = 0;
	}

	rsp->req.sg = rsp->cmd->inline_sg;
	rsp->req.sg_cnt = sg_count;
625
626
627
628
629
630
631
632
633
634
635
}

static u16 nvmet_rdma_map_sgl_inline(struct nvmet_rdma_rsp *rsp)
{
	struct nvme_sgl_desc *sgl = &rsp->req.cmd->common.dptr.sgl;
	u64 off = le64_to_cpu(sgl->addr);
	u32 len = le32_to_cpu(sgl->length);

	if (!nvme_is_write(rsp->req.cmd))
		return NVME_SC_INVALID_FIELD | NVME_SC_DNR;

636
	if (off + len > rsp->queue->dev->inline_data_size) {
637
638
639
640
641
642
643
644
645
646
		pr_err("invalid inline data offset!\n");
		return NVME_SC_SGL_INVALID_OFFSET | NVME_SC_DNR;
	}

	/* no data command? */
	if (!len)
		return 0;

	nvmet_rdma_use_inline_sg(rsp, len, off);
	rsp->flags |= NVMET_RDMA_REQ_INLINE_DATA;
647
	rsp->req.transfer_len += len;
648
649
650
651
652
653
654
655
656
657
658
	return 0;
}

static u16 nvmet_rdma_map_sgl_keyed(struct nvmet_rdma_rsp *rsp,
		struct nvme_keyed_sgl_desc *sgl, bool invalidate)
{
	struct rdma_cm_id *cm_id = rsp->queue->cm_id;
	u64 addr = le64_to_cpu(sgl->addr);
	u32 key = get_unaligned_le32(sgl->key);
	int ret;

659
660
	rsp->req.transfer_len = get_unaligned_le24(sgl->length);

661
	/* no data command? */
662
	if (!rsp->req.transfer_len)
663
664
		return 0;

665
666
667
	ret = nvmet_req_alloc_sgl(&rsp->req);
	if (ret < 0)
		goto error_out;
668
669
670
671
672

	ret = rdma_rw_ctx_init(&rsp->rw, cm_id->qp, cm_id->port_num,
			rsp->req.sg, rsp->req.sg_cnt, 0, addr, key,
			nvmet_data_dir(&rsp->req));
	if (ret < 0)
673
		goto error_out;
674
675
676
677
678
679
680
681
	rsp->n_rdma += ret;

	if (invalidate) {
		rsp->invalidate_rkey = key;
		rsp->flags |= NVMET_RDMA_REQ_INVALIDATE_RKEY;
	}

	return 0;
682
683
684
685

error_out:
	rsp->req.transfer_len = 0;
	return NVME_SC_INTERNAL;
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
}

static u16 nvmet_rdma_map_sgl(struct nvmet_rdma_rsp *rsp)
{
	struct nvme_keyed_sgl_desc *sgl = &rsp->req.cmd->common.dptr.ksgl;

	switch (sgl->type >> 4) {
	case NVME_SGL_FMT_DATA_DESC:
		switch (sgl->type & 0xf) {
		case NVME_SGL_FMT_OFFSET:
			return nvmet_rdma_map_sgl_inline(rsp);
		default:
			pr_err("invalid SGL subtype: %#x\n", sgl->type);
			return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
		}
	case NVME_KEY_SGL_FMT_DATA_DESC:
		switch (sgl->type & 0xf) {
		case NVME_SGL_FMT_ADDRESS | NVME_SGL_FMT_INVALIDATE:
			return nvmet_rdma_map_sgl_keyed(rsp, sgl, true);
		case NVME_SGL_FMT_ADDRESS:
			return nvmet_rdma_map_sgl_keyed(rsp, sgl, false);
		default:
			pr_err("invalid SGL subtype: %#x\n", sgl->type);
			return NVME_SC_INVALID_FIELD | NVME_SC_DNR;
		}
	default:
		pr_err("invalid SGL type: %#x\n", sgl->type);
		return NVME_SC_SGL_INVALID_TYPE | NVME_SC_DNR;
	}
}

static bool nvmet_rdma_execute_command(struct nvmet_rdma_rsp *rsp)
{
	struct nvmet_rdma_queue *queue = rsp->queue;

	if (unlikely(atomic_sub_return(1 + rsp->n_rdma,
			&queue->sq_wr_avail) < 0)) {
		pr_debug("IB send queue full (needed %d): queue %u cntlid %u\n",
				1 + rsp->n_rdma, queue->idx,
				queue->nvme_sq.ctrl->cntlid);
		atomic_add(1 + rsp->n_rdma, &queue->sq_wr_avail);
		return false;
	}

	if (nvmet_rdma_need_data_in(rsp)) {
		if (rdma_rw_ctx_post(&rsp->rw, queue->cm_id->qp,
				queue->cm_id->port_num, &rsp->read_cqe, NULL))
			nvmet_req_complete(&rsp->req, NVME_SC_DATA_XFER_ERROR);
	} else {
735
		nvmet_req_execute(&rsp->req);
736
737
738
739
740
741
742
743
744
745
	}

	return true;
}

static void nvmet_rdma_handle_command(struct nvmet_rdma_queue *queue,
		struct nvmet_rdma_rsp *cmd)
{
	u16 status;

746
747
748
749
750
751
752
	ib_dma_sync_single_for_cpu(queue->dev->device,
		cmd->cmd->sge[0].addr, cmd->cmd->sge[0].length,
		DMA_FROM_DEVICE);
	ib_dma_sync_single_for_cpu(queue->dev->device,
		cmd->send_sge.addr, cmd->send_sge.length,
		DMA_TO_DEVICE);

753
754
	cmd->req.p2p_client = &queue->dev->device->dev;

755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
	if (!nvmet_req_init(&cmd->req, &queue->nvme_cq,
			&queue->nvme_sq, &nvmet_rdma_ops))
		return;

	status = nvmet_rdma_map_sgl(cmd);
	if (status)
		goto out_err;

	if (unlikely(!nvmet_rdma_execute_command(cmd))) {
		spin_lock(&queue->rsp_wr_wait_lock);
		list_add_tail(&cmd->wait_list, &queue->rsp_wr_wait_list);
		spin_unlock(&queue->rsp_wr_wait_lock);
	}

	return;

out_err:
	nvmet_req_complete(&cmd->req, status);
}

static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc)
{
	struct nvmet_rdma_cmd *cmd =
		container_of(wc->wr_cqe, struct nvmet_rdma_cmd, cqe);
	struct nvmet_rdma_queue *queue = cq->cq_context;
	struct nvmet_rdma_rsp *rsp;

	if (unlikely(wc->status != IB_WC_SUCCESS)) {
		if (wc->status != IB_WC_WR_FLUSH_ERR) {
			pr_err("RECV for CQE 0x%p failed with status %s (%d)\n",
				wc->wr_cqe, ib_wc_status_msg(wc->status),
				wc->status);
			nvmet_rdma_error_comp(queue);
		}
		return;
	}

	if (unlikely(wc->byte_len < sizeof(struct nvme_command))) {
		pr_err("Ctrl Fatal Error: capsule size less than 64 bytes\n");
		nvmet_rdma_error_comp(queue);
		return;
	}

	cmd->queue = queue;
	rsp = nvmet_rdma_get_rsp(queue);
800
801
802
803
804
805
806
807
808
	if (unlikely(!rsp)) {
		/*
		 * we get here only under memory pressure,
		 * silently drop and have the host retry
		 * as we can't even fail it.
		 */
		nvmet_rdma_post_recv(queue->dev, cmd);
		return;
	}
809
	rsp->queue = queue;
810
811
812
	rsp->cmd = cmd;
	rsp->flags = 0;
	rsp->req.cmd = cmd->nvme_cmd;
813
814
	rsp->req.port = queue->port;
	rsp->n_rdma = 0;
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849

	if (unlikely(queue->state != NVMET_RDMA_Q_LIVE)) {
		unsigned long flags;

		spin_lock_irqsave(&queue->state_lock, flags);
		if (queue->state == NVMET_RDMA_Q_CONNECTING)
			list_add_tail(&rsp->wait_list, &queue->rsp_wait_list);
		else
			nvmet_rdma_put_rsp(rsp);
		spin_unlock_irqrestore(&queue->state_lock, flags);
		return;
	}

	nvmet_rdma_handle_command(queue, rsp);
}

static void nvmet_rdma_destroy_srq(struct nvmet_rdma_device *ndev)
{
	if (!ndev->srq)
		return;

	nvmet_rdma_free_cmds(ndev, ndev->srq_cmds, ndev->srq_size, false);
	ib_destroy_srq(ndev->srq);
}

static int nvmet_rdma_init_srq(struct nvmet_rdma_device *ndev)
{
	struct ib_srq_init_attr srq_attr = { NULL, };
	struct ib_srq *srq;
	size_t srq_size;
	int ret, i;

	srq_size = 4095;	/* XXX: tune */

	srq_attr.attr.max_wr = srq_size;
850
	srq_attr.attr.max_sge = 1 + ndev->inline_page_count;
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
	srq_attr.attr.srq_limit = 0;
	srq_attr.srq_type = IB_SRQT_BASIC;
	srq = ib_create_srq(ndev->pd, &srq_attr);
	if (IS_ERR(srq)) {
		/*
		 * If SRQs aren't supported we just go ahead and use normal
		 * non-shared receive queues.
		 */
		pr_info("SRQ requested but not supported.\n");
		return 0;
	}

	ndev->srq_cmds = nvmet_rdma_alloc_cmds(ndev, srq_size, false);
	if (IS_ERR(ndev->srq_cmds)) {
		ret = PTR_ERR(ndev->srq_cmds);
		goto out_destroy_srq;
	}

	ndev->srq = srq;
	ndev->srq_size = srq_size;

872
873
874
875
876
	for (i = 0; i < srq_size; i++) {
		ret = nvmet_rdma_post_recv(ndev, &ndev->srq_cmds[i]);
		if (ret)
			goto out_free_cmds;
	}
877
878
879

	return 0;

880
881
out_free_cmds:
	nvmet_rdma_free_cmds(ndev, ndev->srq_cmds, ndev->srq_size, false);
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
out_destroy_srq:
	ib_destroy_srq(srq);
	return ret;
}

static void nvmet_rdma_free_dev(struct kref *ref)
{
	struct nvmet_rdma_device *ndev =
		container_of(ref, struct nvmet_rdma_device, ref);

	mutex_lock(&device_list_mutex);
	list_del(&ndev->entry);
	mutex_unlock(&device_list_mutex);

	nvmet_rdma_destroy_srq(ndev);
	ib_dealloc_pd(ndev->pd);

	kfree(ndev);
}

static struct nvmet_rdma_device *
nvmet_rdma_find_get_device(struct rdma_cm_id *cm_id)
{
905
	struct nvmet_port *port = cm_id->context;
906
	struct nvmet_rdma_device *ndev;
907
908
	int inline_page_count;
	int inline_sge_count;
909
910
911
912
913
914
915
916
917
918
919
920
921
	int ret;

	mutex_lock(&device_list_mutex);
	list_for_each_entry(ndev, &device_list, entry) {
		if (ndev->device->node_guid == cm_id->device->node_guid &&
		    kref_get_unless_zero(&ndev->ref))
			goto out_unlock;
	}

	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL);
	if (!ndev)
		goto out_err;

922
923
	inline_page_count = num_pages(port->inline_data_size);
	inline_sge_count = max(cm_id->device->attrs.max_sge_rd,
924
				cm_id->device->attrs.max_recv_sge) - 1;
925
926
927
928
929
930
931
932
933
	if (inline_page_count > inline_sge_count) {
		pr_warn("inline_data_size %d cannot be supported by device %s. Reducing to %lu.\n",
			port->inline_data_size, cm_id->device->name,
			inline_sge_count * PAGE_SIZE);
		port->inline_data_size = inline_sge_count * PAGE_SIZE;
		inline_page_count = inline_sge_count;
	}
	ndev->inline_data_size = port->inline_data_size;
	ndev->inline_page_count = inline_page_count;
934
935
936
	ndev->device = cm_id->device;
	kref_init(&ndev->ref);

937
	ndev->pd = ib_alloc_pd(ndev->device, 0);
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
	if (IS_ERR(ndev->pd))
		goto out_free_dev;

	if (nvmet_rdma_use_srq) {
		ret = nvmet_rdma_init_srq(ndev);
		if (ret)
			goto out_free_pd;
	}

	list_add(&ndev->entry, &device_list);
out_unlock:
	mutex_unlock(&device_list_mutex);
	pr_debug("added %s.\n", ndev->device->name);
	return ndev;

out_free_pd:
	ib_dealloc_pd(ndev->pd);
out_free_dev:
	kfree(ndev);
out_err:
	mutex_unlock(&device_list_mutex);
	return NULL;
}

static int nvmet_rdma_create_queue_ib(struct nvmet_rdma_queue *queue)
{
	struct ib_qp_init_attr qp_attr;
	struct nvmet_rdma_device *ndev = queue->dev;
	int comp_vector, nr_cqe, ret, i;

	/*
	 * Spread the io queues across completion vectors,
	 * but still keep all admin queues on vector 0.
	 */
	comp_vector = !queue->host_qid ? 0 :
		queue->idx % ndev->device->num_comp_vectors;

	/*
	 * Reserve CQ slots for RECV + RDMA_READ/RDMA_WRITE + RDMA_SEND.
	 */
	nr_cqe = queue->recv_queue_size + 2 * queue->send_queue_size;

	queue->cq = ib_alloc_cq(ndev->device, queue,
			nr_cqe + 1, comp_vector,
			IB_POLL_WORKQUEUE);
	if (IS_ERR(queue->cq)) {
		ret = PTR_ERR(queue->cq);
		pr_err("failed to create CQ cqe= %d ret= %d\n",
		       nr_cqe + 1, ret);
		goto out;
	}

	memset(&qp_attr, 0, sizeof(qp_attr));
	qp_attr.qp_context = queue;
	qp_attr.event_handler = nvmet_rdma_qp_event;
	qp_attr.send_cq = queue->cq;
	qp_attr.recv_cq = queue->cq;
	qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
	qp_attr.qp_type = IB_QPT_RC;
	/* +1 for drain */
	qp_attr.cap.max_send_wr = queue->send_queue_size + 1;
	qp_attr.cap.max_rdma_ctxs = queue->send_queue_size;
	qp_attr.cap.max_send_sge = max(ndev->device->attrs.max_sge_rd,
1001
					ndev->device->attrs.max_send_sge);
1002
1003
1004
1005
1006
1007

	if (ndev->srq) {
		qp_attr.srq = ndev->srq;
	} else {
		/* +1 for drain */
		qp_attr.cap.max_recv_wr = 1 + queue->recv_queue_size;
1008
		qp_attr.cap.max_recv_sge = 1 + ndev->inline_page_count;
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
	}

	ret = rdma_create_qp(queue->cm_id, ndev->pd, &qp_attr);
	if (ret) {
		pr_err("failed to create_qp ret= %d\n", ret);
		goto err_destroy_cq;
	}

	atomic_set(&queue->sq_wr_avail, qp_attr.cap.max_send_wr);

	pr_debug("%s: max_cqe= %d max_sge= %d sq_size = %d cm_id= %p\n",
		 __func__, queue->cq->cqe, qp_attr.cap.max_send_sge,
		 qp_attr.cap.max_send_wr, queue->cm_id);

	if (!ndev->srq) {
		for (i = 0; i < queue->recv_queue_size; i++) {
			queue->cmds[i].queue = queue;
1026
1027
1028
			ret = nvmet_rdma_post_recv(ndev, &queue->cmds[i]);
			if (ret)
				goto err_destroy_qp;
1029
1030
1031
1032
1033
1034
		}
	}

out:
	return ret;

1035
1036
err_destroy_qp:
	rdma_destroy_qp(queue->cm_id);
1037
1038
1039
1040
1041
1042
1043
err_destroy_cq:
	ib_free_cq(queue->cq);
	goto out;
}

static void nvmet_rdma_destroy_queue_ib(struct nvmet_rdma_queue *queue)
{
1044
1045
1046
1047
1048
	struct ib_qp *qp = queue->cm_id->qp;

	ib_drain_qp(qp);
	rdma_destroy_id(queue->cm_id);
	ib_destroy_qp(qp);
1049
1050
1051
1052
1053
	ib_free_cq(queue->cq);
}

static void nvmet_rdma_free_queue(struct nvmet_rdma_queue *queue)
{
1054
	pr_debug("freeing queue %d\n", queue->idx);
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075

	nvmet_sq_destroy(&queue->nvme_sq);

	nvmet_rdma_destroy_queue_ib(queue);
	if (!queue->dev->srq) {
		nvmet_rdma_free_cmds(queue->dev, queue->cmds,
				queue->recv_queue_size,
				!queue->host_qid);
	}
	nvmet_rdma_free_rsps(queue);
	ida_simple_remove(&nvmet_rdma_queue_ida, queue->idx);
	kfree(queue);
}

static void nvmet_rdma_release_queue_work(struct work_struct *w)
{
	struct nvmet_rdma_queue *queue =
		container_of(w, struct nvmet_rdma_queue, release_work);
	struct nvmet_rdma_device *dev = queue->dev;

	nvmet_rdma_free_queue(queue);
1076

1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
	kref_put(&dev->ref, nvmet_rdma_free_dev);
}

static int
nvmet_rdma_parse_cm_connect_req(struct rdma_conn_param *conn,
				struct nvmet_rdma_queue *queue)
{
	struct nvme_rdma_cm_req *req;

	req = (struct nvme_rdma_cm_req *)conn->private_data;
	if (!req || conn->private_data_len == 0)
		return NVME_RDMA_CM_INVALID_LEN;

	if (le16_to_cpu(req->recfmt) != NVME_RDMA_CM_FMT_1_0)
		return NVME_RDMA_CM_INVALID_RECFMT;

	queue->host_qid = le16_to_cpu(req->qid);

	/*
1096
	 * req->hsqsize corresponds to our recv queue size plus 1
1097
1098
	 * req->hrqsize corresponds to our send queue size
	 */
1099
	queue->recv_queue_size = le16_to_cpu(req->hsqsize) + 1;
1100
1101
	queue->send_queue_size = le16_to_cpu(req->hrqsize);

1102
	if (!queue->host_qid && queue->recv_queue_size > NVME_AQ_DEPTH)
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
		return NVME_RDMA_CM_INVALID_HSQSIZE;

	/* XXX: Should we enforce some kind of max for IO queues? */

	return 0;
}

static int nvmet_rdma_cm_reject(struct rdma_cm_id *cm_id,
				enum nvme_rdma_cm_status status)
{
	struct nvme_rdma_cm_rej rej;

1115
1116
1117
	pr_debug("rejecting connect request: status %d (%s)\n",
		 status, nvme_rdma_cm_msg(status));

1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
	rej.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
	rej.sts = cpu_to_le16(status);

	return rdma_reject(cm_id, (void *)&rej, sizeof(rej));
}

static struct nvmet_rdma_queue *
nvmet_rdma_alloc_queue(struct nvmet_rdma_device *ndev,
		struct rdma_cm_id *cm_id,
		struct rdma_cm_event *event)
{
	struct nvmet_rdma_queue *queue;
	int ret;

	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
	if (!queue) {
		ret = NVME_RDMA_CM_NO_RSC;
		goto out_reject;
	}

	ret = nvmet_sq_init(&queue->nvme_sq);
1139
1140
	if (ret) {
		ret = NVME_RDMA_CM_NO_RSC;
1141
		goto out_free_queue;
1142
	}
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162

	ret = nvmet_rdma_parse_cm_connect_req(&event->param.conn, queue);
	if (ret)
		goto out_destroy_sq;

	/*
	 * Schedules the actual release because calling rdma_destroy_id from
	 * inside a CM callback would trigger a deadlock. (great API design..)
	 */
	INIT_WORK(&queue->release_work, nvmet_rdma_release_queue_work);
	queue->dev = ndev;
	queue->cm_id = cm_id;

	spin_lock_init(&queue->state_lock);
	queue->state = NVMET_RDMA_Q_CONNECTING;
	INIT_LIST_HEAD(&queue->rsp_wait_list);
	INIT_LIST_HEAD(&queue->rsp_wr_wait_list);
	spin_lock_init(&queue->rsp_wr_wait_lock);
	INIT_LIST_HEAD(&queue->free_rsps);
	spin_lock_init(&queue->rsps_lock);
1163
	INIT_LIST_HEAD(&queue->queue_list);
1164
1165
1166
1167

	queue->idx = ida_simple_get(&nvmet_rdma_queue_ida, 0, 0, GFP_KERNEL);
	if (queue->idx < 0) {
		ret = NVME_RDMA_CM_NO_RSC;
1168
		goto out_destroy_sq;
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
	}

	ret = nvmet_rdma_alloc_rsps(queue);
	if (ret) {
		ret = NVME_RDMA_CM_NO_RSC;
		goto out_ida_remove;
	}

	if (!ndev->srq) {
		queue->cmds = nvmet_rdma_alloc_cmds(ndev,
				queue->recv_queue_size,
				!queue->host_qid);
		if (IS_ERR(queue->cmds)) {
			ret = NVME_RDMA_CM_NO_RSC;
			goto out_free_responses;
		}
	}

	ret = nvmet_rdma_create_queue_ib(queue);
	if (ret) {
		pr_err("%s: creating RDMA queue failed (%d).\n",
			__func__, ret);
		ret = NVME_RDMA_CM_NO_RSC;
		goto out_free_cmds;
	}

	return queue;

out_free_cmds:
	if (!ndev->srq) {
		nvmet_rdma_free_cmds(queue->dev, queue->cmds,
				queue->recv_queue_size,
				!queue->host_qid);
	}
out_free_responses:
	nvmet_rdma_free_rsps(queue);
out_ida_remove:
	ida_simple_remove(&nvmet_rdma_queue_ida, queue->idx);
out_destroy_sq:
	nvmet_sq_destroy(&queue->nvme_sq);
out_free_queue:
	kfree(queue);
out_reject:
	nvmet_rdma_cm_reject(cm_id, ret);
	return NULL;
}

static void nvmet_rdma_qp_event(struct ib_event *event, void *priv)
{
	struct nvmet_rdma_queue *queue = priv;

	switch (event->event) {
	case IB_EVENT_COMM_EST:
		rdma_notify(queue->cm_id, event->event);
		break;
	default:
1225
1226
		pr_err("received IB QP event: %s (%d)\n",
		       ib_event_msg(event->event), event->event);
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
		break;
	}
}

static int nvmet_rdma_cm_accept(struct rdma_cm_id *cm_id,
		struct nvmet_rdma_queue *queue,
		struct rdma_conn_param *p)
{
	struct rdma_conn_param  param = { };
	struct nvme_rdma_cm_rep priv = { };
	int ret = -ENOMEM;

	param.rnr_retry_count = 7;
	param.flow_control = 1;
	param.initiator_depth = min_t(u8, p->initiator_depth,
		queue->dev->device->attrs.max_qp_init_rd_atom);
	param.private_data = &priv;
	param.private_data_len = sizeof(priv);
	priv.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0);
	priv.crqsize = cpu_to_le16(queue->recv_queue_size);

	ret = rdma_accept(cm_id, &param);
	if (ret)
		pr_err("rdma_accept failed (error code = %d)\n", ret);

	return ret;
}

static int nvmet_rdma_queue_connect(struct rdma_cm_id *cm_id,
		struct rdma_cm_event *event)
{
	struct nvmet_rdma_device *ndev;
	struct nvmet_rdma_queue *queue;
	int ret = -EINVAL;

	ndev = nvmet_rdma_find_get_device(cm_id);
	if (!ndev) {
		nvmet_rdma_cm_reject(cm_id, NVME_RDMA_CM_NO_RSC);
		return -ECONNREFUSED;
	}

	queue = nvmet_rdma_alloc_queue(ndev, cm_id, event);
	if (!queue) {
		ret = -ENOMEM;
		goto put_device;
	}
	queue->port = cm_id->context;

1275
1276
	if (queue->host_qid == 0) {
		/* Let inflight controller teardown complete */
1277
		flush_scheduled_work();
1278
1279
	}

1280
	ret = nvmet_rdma_cm_accept(cm_id, queue, &event->param.conn);
1281
	if (ret) {
1282
		schedule_work(&queue->release_work);
1283
1284
1285
		/* Destroying rdma_cm id is not needed here */
		return 0;
	}
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337

	mutex_lock(&nvmet_rdma_queue_mutex);
	list_add_tail(&queue->queue_list, &nvmet_rdma_queue_list);
	mutex_unlock(&nvmet_rdma_queue_mutex);

	return 0;

put_device:
	kref_put(&ndev->ref, nvmet_rdma_free_dev);

	return ret;
}

static void nvmet_rdma_queue_established(struct nvmet_rdma_queue *queue)
{
	unsigned long flags;

	spin_lock_irqsave(&queue->state_lock, flags);
	if (queue->state != NVMET_RDMA_Q_CONNECTING) {
		pr_warn("trying to establish a connected queue\n");
		goto out_unlock;
	}
	queue->state = NVMET_RDMA_Q_LIVE;

	while (!list_empty(&queue->rsp_wait_list)) {
		struct nvmet_rdma_rsp *cmd;

		cmd = list_first_entry(&queue->rsp_wait_list,
					struct nvmet_rdma_rsp, wait_list);
		list_del(&cmd->wait_list);

		spin_unlock_irqrestore(&queue->state_lock, flags);
		nvmet_rdma_handle_command(queue, cmd);
		spin_lock_irqsave(&queue->state_lock, flags);
	}

out_unlock:
	spin_unlock_irqrestore(&queue->state_lock, flags);
}

static void __nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue)
{
	bool disconnect = false;
	unsigned long flags;

	pr_debug("cm_id= %p queue->state= %d\n", queue->cm_id, queue->state);

	spin_lock_irqsave(&queue->state_lock, flags);
	switch (queue->state) {
	case NVMET_RDMA_Q_CONNECTING:
	case NVMET_RDMA_Q_LIVE:
		queue->state = NVMET_RDMA_Q_DISCONNECTING;
1338
		disconnect = true;
1339
1340
1341
1342
1343
1344
1345
1346
		break;
	case NVMET_RDMA_Q_DISCONNECTING:
		break;
	}
	spin_unlock_irqrestore(&queue->state_lock, flags);

	if (disconnect) {
		rdma_disconnect(queue->cm_id);
1347
		schedule_work(&queue->release_work);
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
	}
}

static void nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue)
{
	bool disconnect = false;

	mutex_lock(&nvmet_rdma_queue_mutex);
	if (!list_empty(&queue->queue_list)) {
		list_del_init(&queue->queue_list);
		disconnect = true;
	}
	mutex_unlock(&nvmet_rdma_queue_mutex);

	if (disconnect)
		__nvmet_rdma_queue_disconnect(queue);
}

static void nvmet_rdma_queue_connect_fail(struct rdma_cm_id *cm_id,
		struct nvmet_rdma_queue *queue)
{
	WARN_ON_ONCE(queue->state != NVMET_RDMA_Q_CONNECTING);

1371
1372
1373
1374
1375
1376
	mutex_lock(&nvmet_rdma_queue_mutex);
	if (!list_empty(&queue->queue_list))
		list_del_init(&queue->queue_list);
	mutex_unlock(&nvmet_rdma_queue_mutex);

	pr_err("failed to connect queue %d\n", queue->idx);
1377
	schedule_work(&queue->release_work);
1378
1379
}

1380
1381
/**
 * nvme_rdma_device_removal() - Handle RDMA device removal
1382
 * @cm_id:	rdma_cm id, used for nvmet port
1383
1384
1385
 * @queue:      nvmet rdma queue (cm id qp_context)
 *
 * DEVICE_REMOVAL event notifies us that the RDMA device is about
1386
1387
1388
 * to unplug. Note that this event can be generated on a normal
 * queue cm_id and/or a device bound listener cm_id (where in this
 * case queue will be null).
1389
 *
1390
1391
 * We registered an ib_client to handle device removal for queues,
 * so we only need to handle the listening port cm_ids. In this case
1392
1393
1394
1395
1396
1397
 * we nullify the priv to prevent double cm_id destruction and destroying
 * the cm_id implicitely by returning a non-zero rc to the callout.
 */
static int nvmet_rdma_device_removal(struct rdma_cm_id *cm_id,
		struct nvmet_rdma_queue *queue)
{
1398
	struct nvmet_port *port;
1399

1400
	if (queue) {
1401
		/*
1402
1403
1404
		 * This is a queue cm_id. we have registered
		 * an ib_client to handle queues removal
		 * so don't interfear and just return.
1405
		 */
1406
		return 0;
1407
1408
	}

1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
	port = cm_id->context;

	/*
	 * This is a listener cm_id. Make sure that
	 * future remove_port won't invoke a double
	 * cm_id destroy. use atomic xchg to make sure
	 * we don't compete with remove_port.
	 */
	if (xchg(&port->priv, NULL) != cm_id)
		return 0;

1420
1421
1422
1423
1424
1425
1426
	/*
	 * We need to return 1 so that the core will destroy
	 * it's own ID.  What a great API design..
	 */
	return 1;
}

1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
static int nvmet_rdma_cm_handler(struct rdma_cm_id *cm_id,
		struct rdma_cm_event *event)
{
	struct nvmet_rdma_queue *queue = NULL;
	int ret = 0;

	if (cm_id->qp)
		queue = cm_id->qp->qp_context;

	pr_debug("%s (%d): status %d id %p\n",
		rdma_event_msg(event->event), event->event,
		event->status, cm_id);

	switch (event->event) {
	case RDMA_CM_EVENT_CONNECT_REQUEST:
		ret = nvmet_rdma_queue_connect(cm_id, event);
		break;
	case RDMA_CM_EVENT_ESTABLISHED:
		nvmet_rdma_queue_established(queue);
		break;
	case RDMA_CM_EVENT_ADDR_CHANGE:
	case RDMA_CM_EVENT_DISCONNECTED:
	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
1450
		nvmet_rdma_queue_disconnect(queue);
1451
1452
1453
		break;
	case RDMA_CM_EVENT_DEVICE_REMOVAL:
		ret = nvmet_rdma_device_removal(cm_id, queue);
1454
1455
		break;
	case RDMA_CM_EVENT_REJECTED:
1456
1457
1458
		pr_debug("Connection rejected: %s\n",
			 rdma_reject_msg(cm_id, event->status));
		/* FALLTHROUGH */
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
	case RDMA_CM_EVENT_UNREACHABLE:
	case RDMA_CM_EVENT_CONNECT_ERROR:
		nvmet_rdma_queue_connect_fail(cm_id, queue);
		break;
	default:
		pr_err("received unrecognized RDMA CM event %d\n",
			event->event);
		break;
	}

	return ret;
}

static void nvmet_rdma_delete_ctrl(struct nvmet_ctrl *ctrl)
{
	struct nvmet_rdma_queue *queue;

restart:
	mutex_lock(&nvmet_rdma_queue_mutex);
	list_for_each_entry(queue, &nvmet_rdma_queue_list, queue_list) {
		if (queue->nvme_sq.ctrl == ctrl) {
			list_del_init(&queue->queue_list);
			mutex_unlock(&nvmet_rdma_queue_mutex);

			__nvmet_rdma_queue_disconnect(queue);
			goto restart;
		}
	}
	mutex_unlock(&nvmet_rdma_queue_mutex);
}

static int nvmet_rdma_add_port(struct nvmet_port *port)
{
	struct rdma_cm_id *cm_id;
1493
1494
	struct sockaddr_storage addr = { };
	__kernel_sa_family_t af;
1495
1496
1497
1498
	int ret;

	switch (port->disc_addr.adrfam) {
	case NVMF_ADDR_FAMILY_IP4:
1499
1500
1501
1502
		af = AF_INET;
		break;
	case NVMF_ADDR_FAMILY_IP6:
		af = AF_INET6;
1503
1504
1505
1506
1507
1508
1509
		break;
	default:
		pr_err("address family %d not supported\n",
				port->disc_addr.adrfam);
		return -EINVAL;
	}

1510
1511
1512
1513
1514
1515
1516
1517
1518
	if (port->inline_data_size < 0) {
		port->inline_data_size = NVMET_RDMA_DEFAULT_INLINE_DATA_SIZE;
	} else if (port->inline_data_size > NVMET_RDMA_MAX_INLINE_DATA_SIZE) {
		pr_warn("inline_data_size %u is too large, reducing to %u\n",
			port->inline_data_size,
			NVMET_RDMA_MAX_INLINE_DATA_SIZE);
		port->inline_data_size = NVMET_RDMA_MAX_INLINE_DATA_SIZE;
	}

1519
1520
1521
1522
1523
	ret = inet_pton_with_scope(&init_net, af, port->disc_addr.traddr,
			port->disc_addr.trsvcid, &addr);
	if (ret) {
		pr_err("malformed ip/port passed: %s:%s\n",
			port->disc_addr.traddr, port->disc_addr.trsvcid);
1524
		return ret;
1525
	}
1526
1527
1528
1529
1530
1531
1532
1533

	cm_id = rdma_create_id(&init_net, nvmet_rdma_cm_handler, port,
			RDMA_PS_TCP, IB_QPT_RC);
	if (IS_ERR(cm_id)) {
		pr_err("CM ID creation failed\n");
		return PTR_ERR(cm_id);
	}

1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
	/*
	 * Allow both IPv4 and IPv6 sockets to bind a single port
	 * at the same time.
	 */
	ret = rdma_set_afonly(cm_id, 1);
	if (ret) {
		pr_err("rdma_set_afonly failed (%d)\n", ret);
		goto out_destroy_id;
	}

	ret = rdma_bind_addr(cm_id, (struct sockaddr *)&addr);
1545
	if (ret) {
1546
1547
		pr_err("binding CM ID to %pISpcs failed (%d)\n",
			(struct sockaddr *)&addr, ret);
1548
1549
1550
1551
1552
		goto out_destroy_id;
	}

	ret = rdma_listen(cm_id, 128);
	if (ret) {
1553
1554
		pr_err("listening to %pISpcs failed (%d)\n",
			(struct sockaddr *)&addr, ret);
1555
1556
1557
		goto out_destroy_id;
	}

1558
1559
	pr_info("enabling port %d (%pISpcs)\n",
		le16_to_cpu(port->disc_addr.portid), (struct sockaddr *)&addr);
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
	port->priv = cm_id;
	return 0;

out_destroy_id:
	rdma_destroy_id(cm_id);
	return ret;
}

static void nvmet_rdma_remove_port(struct nvmet_port *port)
{
1570
	struct rdma_cm_id *cm_id = xchg(&port->priv, NULL);
1571

1572
1573
	if (cm_id)
		rdma_destroy_id(cm_id);
1574
1575
}

1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
static void nvmet_rdma_disc_port_addr(struct nvmet_req *req,
		struct nvmet_port *port, char *traddr)
{
	struct rdma_cm_id *cm_id = port->priv;

	if (inet_addr_is_any((struct sockaddr *)&cm_id->route.addr.src_addr)) {
		struct nvmet_rdma_rsp *rsp =
			container_of(req, struct nvmet_rdma_rsp, req);
		struct rdma_cm_id *req_cm_id = rsp->queue->cm_id;
		struct sockaddr *addr = (void *)&req_cm_id->route.addr.src_addr;

		sprintf(traddr, "%pISc", addr);
	} else {
		memcpy(traddr, port->disc_addr.traddr, NVMF_TRADDR_SIZE);
	}
}

1593
static const struct nvmet_fabrics_ops nvmet_rdma_ops = {
1594
1595
1596
1597
1598
1599
1600
1601
	.owner			= THIS_MODULE,
	.type			= NVMF_TRTYPE_RDMA,
	.msdbd			= 1,
	.has_keyed_sgls		= 1,
	.add_port		= nvmet_rdma_add_port,
	.remove_port		= nvmet_rdma_remove_port,
	.queue_response		= nvmet_rdma_queue_response,
	.delete_ctrl		= nvmet_rdma_delete_ctrl,
1602
	.disc_traddr		= nvmet_rdma_disc_port_addr,
1603
1604
};

1605
1606
static void nvmet_rdma_remove_one(struct ib_device *ib_device, void *client_data)
{
1607
	struct nvmet_rdma_queue *queue, *tmp;
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
	struct nvmet_rdma_device *ndev;
	bool found = false;

	mutex_lock(&device_list_mutex);
	list_for_each_entry(ndev, &device_list, entry) {
		if (ndev->device == ib_device) {
			found = true;
			break;
		}
	}
	mutex_unlock(&device_list_mutex);

	if (!found)
		return;
1622

1623
1624
1625
1626
	/*
	 * IB Device that is used by nvmet controllers is being removed,
	 * delete all queues using this device.
	 */
1627
	mutex_lock(&nvmet_rdma_queue_mutex);
1628
1629
	list_for_each_entry_safe(queue, tmp, &nvmet_rdma_queue_list,
				 queue_list) {
1630
1631
1632
1633
		if (queue->dev->device != ib_device)
			continue;

		pr_info("Removing queue %d\n", queue->idx);
1634
		list_del_init(&queue->queue_list);
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
		__nvmet_rdma_queue_disconnect(queue);
	}
	mutex_unlock(&nvmet_rdma_queue_mutex);

	flush_scheduled_work();
}

static struct ib_client nvmet_rdma_ib_client = {
	.name   = "nvmet_rdma",
	.remove = nvmet_rdma_remove_one
};

1647
1648
static int __init nvmet_rdma_init(void)
{
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
	int ret;

	ret = ib_register_client(&nvmet_rdma_ib_client);
	if (ret)
		return ret;

	ret = nvmet_register_transport(&nvmet_rdma_ops);
	if (ret)
		goto err_ib_client;

	return 0;

err_ib_client:
	ib_unregister_client(&nvmet_rdma_ib_client);
	return ret;
1664
1665
1666
1667
1668
}

static void __exit nvmet_rdma_exit(void)
{
	nvmet_unregister_transport(&nvmet_rdma_ops);
1669
	ib_unregister_client(&nvmet_rdma_ib_client);
1670
	WARN_ON_ONCE(!list_empty(&nvmet_rdma_queue_list));
1671
1672
1673
1674
1675
1676
1677
1678
	ida_destroy(&nvmet_rdma_queue_ida);
}

module_init(nvmet_rdma_init);
module_exit(nvmet_rdma_exit);

MODULE_LICENSE("GPL v2");
MODULE_ALIAS("nvmet-transport-1"); /* 1 == NVMF_TRTYPE_RDMA */