1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * RDMA Transport Layer
4 *
5 * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
6 * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
7 * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
8 */
9#undef pr_fmt
10#define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
11
12#include <linux/module.h>
13#include <linux/inet.h>
14
15#include "rtrs-pri.h"
16#include "rtrs-log.h"
17
18MODULE_DESCRIPTION("RDMA Transport Core");
19MODULE_LICENSE("GPL");
20
21struct rtrs_iu *rtrs_iu_alloc(u32 queue_size, size_t size, gfp_t gfp_mask,
22			      struct ib_device *dma_dev,
23			      enum dma_data_direction dir,
24			      void (*done)(struct ib_cq *cq, struct ib_wc *wc))
25{
26	struct rtrs_iu *ius, *iu;
27	int i;
28
29	ius = kcalloc(queue_size, sizeof(*ius), gfp_mask);
30	if (!ius)
31		return NULL;
32	for (i = 0; i < queue_size; i++) {
33		iu = &ius[i];
34		iu->direction = dir;
35		iu->buf = kzalloc(size, gfp_mask);
36		if (!iu->buf)
37			goto err;
38
39		iu->dma_addr = ib_dma_map_single(dma_dev, iu->buf, size, dir);
40		if (ib_dma_mapping_error(dma_dev, iu->dma_addr)) {
41			kfree(iu->buf);
42			goto err;
43		}
44
45		iu->cqe.done  = done;
46		iu->size      = size;
47	}
48	return ius;
49err:
50	rtrs_iu_free(ius, dma_dev, i);
51	return NULL;
52}
53EXPORT_SYMBOL_GPL(rtrs_iu_alloc);
54
55void rtrs_iu_free(struct rtrs_iu *ius, struct ib_device *ibdev, u32 queue_size)
56{
57	struct rtrs_iu *iu;
58	int i;
59
60	if (!ius)
61		return;
62
63	for (i = 0; i < queue_size; i++) {
64		iu = &ius[i];
65		ib_dma_unmap_single(ibdev, iu->dma_addr, iu->size, iu->direction);
66		kfree(iu->buf);
67	}
68	kfree(ius);
69}
70EXPORT_SYMBOL_GPL(rtrs_iu_free);
71
72int rtrs_iu_post_recv(struct rtrs_con *con, struct rtrs_iu *iu)
73{
74	struct rtrs_sess *sess = con->sess;
75	struct ib_recv_wr wr;
76	struct ib_sge list;
77
78	list.addr   = iu->dma_addr;
79	list.length = iu->size;
80	list.lkey   = sess->dev->ib_pd->local_dma_lkey;
81
82	if (list.length == 0) {
83		rtrs_wrn(con->sess,
84			  "Posting receive work request failed, sg list is empty\n");
85		return -EINVAL;
86	}
87	wr = (struct ib_recv_wr) {
88		.wr_cqe  = &iu->cqe,
89		.sg_list = &list,
90		.num_sge = 1,
91	};
92
93	return ib_post_recv(con->qp, &wr, NULL);
94}
95EXPORT_SYMBOL_GPL(rtrs_iu_post_recv);
96
97int rtrs_post_recv_empty(struct rtrs_con *con, struct ib_cqe *cqe)
98{
99	struct ib_recv_wr wr;
100
101	wr = (struct ib_recv_wr) {
102		.wr_cqe  = cqe,
103	};
104
105	return ib_post_recv(con->qp, &wr, NULL);
106}
107EXPORT_SYMBOL_GPL(rtrs_post_recv_empty);
108
109static int rtrs_post_send(struct ib_qp *qp, struct ib_send_wr *head,
110			     struct ib_send_wr *wr)
111{
112	if (head) {
113		struct ib_send_wr *tail = head;
114
115		while (tail->next)
116			tail = tail->next;
117		tail->next = wr;
118	} else {
119		head = wr;
120	}
121
122	return ib_post_send(qp, head, NULL);
123}
124
125int rtrs_iu_post_send(struct rtrs_con *con, struct rtrs_iu *iu, size_t size,
126		       struct ib_send_wr *head)
127{
128	struct rtrs_sess *sess = con->sess;
129	struct ib_send_wr wr;
130	struct ib_sge list;
131
132	if (WARN_ON(size == 0))
133		return -EINVAL;
134
135	list.addr   = iu->dma_addr;
136	list.length = size;
137	list.lkey   = sess->dev->ib_pd->local_dma_lkey;
138
139	wr = (struct ib_send_wr) {
140		.wr_cqe     = &iu->cqe,
141		.sg_list    = &list,
142		.num_sge    = 1,
143		.opcode     = IB_WR_SEND,
144		.send_flags = IB_SEND_SIGNALED,
145	};
146
147	return rtrs_post_send(con->qp, head, &wr);
148}
149EXPORT_SYMBOL_GPL(rtrs_iu_post_send);
150
151int rtrs_iu_post_rdma_write_imm(struct rtrs_con *con, struct rtrs_iu *iu,
152				 struct ib_sge *sge, unsigned int num_sge,
153				 u32 rkey, u64 rdma_addr, u32 imm_data,
154				 enum ib_send_flags flags,
155				 struct ib_send_wr *head)
156{
157	struct ib_rdma_wr wr;
158	int i;
159
160	wr = (struct ib_rdma_wr) {
161		.wr.wr_cqe	  = &iu->cqe,
162		.wr.sg_list	  = sge,
163		.wr.num_sge	  = num_sge,
164		.rkey		  = rkey,
165		.remote_addr	  = rdma_addr,
166		.wr.opcode	  = IB_WR_RDMA_WRITE_WITH_IMM,
167		.wr.ex.imm_data = cpu_to_be32(imm_data),
168		.wr.send_flags  = flags,
169	};
170
171	/*
172	 * If one of the sges has 0 size, the operation will fail with a
173	 * length error
174	 */
175	for (i = 0; i < num_sge; i++)
176		if (WARN_ON(sge[i].length == 0))
177			return -EINVAL;
178
179	return rtrs_post_send(con->qp, head, &wr.wr);
180}
181EXPORT_SYMBOL_GPL(rtrs_iu_post_rdma_write_imm);
182
183int rtrs_post_rdma_write_imm_empty(struct rtrs_con *con, struct ib_cqe *cqe,
184				    u32 imm_data, enum ib_send_flags flags,
185				    struct ib_send_wr *head)
186{
187	struct ib_rdma_wr wr;
188
189	wr = (struct ib_rdma_wr) {
190		.wr.wr_cqe	= cqe,
191		.wr.send_flags	= flags,
192		.wr.opcode	= IB_WR_RDMA_WRITE_WITH_IMM,
193		.wr.ex.imm_data	= cpu_to_be32(imm_data),
194	};
195
196	return rtrs_post_send(con->qp, head, &wr.wr);
197}
198EXPORT_SYMBOL_GPL(rtrs_post_rdma_write_imm_empty);
199
200static void qp_event_handler(struct ib_event *ev, void *ctx)
201{
202	struct rtrs_con *con = ctx;
203
204	switch (ev->event) {
205	case IB_EVENT_COMM_EST:
206		rtrs_info(con->sess, "QP event %s (%d) received\n",
207			   ib_event_msg(ev->event), ev->event);
208		rdma_notify(con->cm_id, IB_EVENT_COMM_EST);
209		break;
210	default:
211		rtrs_info(con->sess, "Unhandled QP event %s (%d) received\n",
212			   ib_event_msg(ev->event), ev->event);
213		break;
214	}
215}
216
217static int create_cq(struct rtrs_con *con, int cq_vector, u16 cq_size,
218		     enum ib_poll_context poll_ctx)
219{
220	struct rdma_cm_id *cm_id = con->cm_id;
221	struct ib_cq *cq;
222
223	cq = ib_alloc_cq(cm_id->device, con, cq_size,
224			 cq_vector, poll_ctx);
225	if (IS_ERR(cq)) {
226		rtrs_err(con->sess, "Creating completion queue failed, errno: %ld\n",
227			  PTR_ERR(cq));
228		return PTR_ERR(cq);
229	}
230	con->cq = cq;
231
232	return 0;
233}
234
235static int create_qp(struct rtrs_con *con, struct ib_pd *pd,
236		     u32 max_send_wr, u32 max_recv_wr, u32 max_sge)
237{
238	struct ib_qp_init_attr init_attr = {NULL};
239	struct rdma_cm_id *cm_id = con->cm_id;
240	int ret;
241
242	init_attr.cap.max_send_wr = max_send_wr;
243	init_attr.cap.max_recv_wr = max_recv_wr;
244	init_attr.cap.max_recv_sge = 1;
245	init_attr.event_handler = qp_event_handler;
246	init_attr.qp_context = con;
247	init_attr.cap.max_send_sge = max_sge;
248
249	init_attr.qp_type = IB_QPT_RC;
250	init_attr.send_cq = con->cq;
251	init_attr.recv_cq = con->cq;
252	init_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
253
254	ret = rdma_create_qp(cm_id, pd, &init_attr);
255	if (ret) {
256		rtrs_err(con->sess, "Creating QP failed, err: %d\n", ret);
257		return ret;
258	}
259	con->qp = cm_id->qp;
260
261	return ret;
262}
263
264int rtrs_cq_qp_create(struct rtrs_sess *sess, struct rtrs_con *con,
265		       u32 max_send_sge, int cq_vector, int cq_size,
266		       u32 max_send_wr, u32 max_recv_wr,
267		       enum ib_poll_context poll_ctx)
268{
269	int err;
270
271	err = create_cq(con, cq_vector, cq_size, poll_ctx);
272	if (err)
273		return err;
274
275	err = create_qp(con, sess->dev->ib_pd, max_send_wr, max_recv_wr,
276			max_send_sge);
277	if (err) {
278		ib_free_cq(con->cq);
279		con->cq = NULL;
280		return err;
281	}
282	con->sess = sess;
283
284	return 0;
285}
286EXPORT_SYMBOL_GPL(rtrs_cq_qp_create);
287
288void rtrs_cq_qp_destroy(struct rtrs_con *con)
289{
290	if (con->qp) {
291		rdma_destroy_qp(con->cm_id);
292		con->qp = NULL;
293	}
294	if (con->cq) {
295		ib_free_cq(con->cq);
296		con->cq = NULL;
297	}
298}
299EXPORT_SYMBOL_GPL(rtrs_cq_qp_destroy);
300
301static void schedule_hb(struct rtrs_sess *sess)
302{
303	queue_delayed_work(sess->hb_wq, &sess->hb_dwork,
304			   msecs_to_jiffies(sess->hb_interval_ms));
305}
306
307void rtrs_send_hb_ack(struct rtrs_sess *sess)
308{
309	struct rtrs_con *usr_con = sess->con[0];
310	u32 imm;
311	int err;
312
313	imm = rtrs_to_imm(RTRS_HB_ACK_IMM, 0);
314	err = rtrs_post_rdma_write_imm_empty(usr_con, sess->hb_cqe, imm,
315					     0, NULL);
316	if (err) {
317		sess->hb_err_handler(usr_con);
318		return;
319	}
320}
321EXPORT_SYMBOL_GPL(rtrs_send_hb_ack);
322
323static void hb_work(struct work_struct *work)
324{
325	struct rtrs_con *usr_con;
326	struct rtrs_sess *sess;
327	u32 imm;
328	int err;
329
330	sess = container_of(to_delayed_work(work), typeof(*sess), hb_dwork);
331	usr_con = sess->con[0];
332
333	if (sess->hb_missed_cnt > sess->hb_missed_max) {
334		sess->hb_err_handler(usr_con);
335		return;
336	}
337	if (sess->hb_missed_cnt++) {
338		/* Reschedule work without sending hb */
339		schedule_hb(sess);
340		return;
341	}
342	imm = rtrs_to_imm(RTRS_HB_MSG_IMM, 0);
343	err = rtrs_post_rdma_write_imm_empty(usr_con, sess->hb_cqe, imm,
344					     0, NULL);
345	if (err) {
346		sess->hb_err_handler(usr_con);
347		return;
348	}
349
350	schedule_hb(sess);
351}
352
353void rtrs_init_hb(struct rtrs_sess *sess, struct ib_cqe *cqe,
354		  unsigned int interval_ms, unsigned int missed_max,
355		  void (*err_handler)(struct rtrs_con *con),
356		  struct workqueue_struct *wq)
357{
358	sess->hb_cqe = cqe;
359	sess->hb_interval_ms = interval_ms;
360	sess->hb_err_handler = err_handler;
361	sess->hb_wq = wq;
362	sess->hb_missed_max = missed_max;
363	sess->hb_missed_cnt = 0;
364	INIT_DELAYED_WORK(&sess->hb_dwork, hb_work);
365}
366EXPORT_SYMBOL_GPL(rtrs_init_hb);
367
368void rtrs_start_hb(struct rtrs_sess *sess)
369{
370	schedule_hb(sess);
371}
372EXPORT_SYMBOL_GPL(rtrs_start_hb);
373
374void rtrs_stop_hb(struct rtrs_sess *sess)
375{
376	cancel_delayed_work_sync(&sess->hb_dwork);
377	sess->hb_missed_cnt = 0;
378}
379EXPORT_SYMBOL_GPL(rtrs_stop_hb);
380
381static int rtrs_str_gid_to_sockaddr(const char *addr, size_t len,
382				     short port, struct sockaddr_storage *dst)
383{
384	struct sockaddr_ib *dst_ib = (struct sockaddr_ib *)dst;
385	int ret;
386
387	/*
388	 * We can use some of the IPv6 functions since GID is a valid
389	 * IPv6 address format
390	 */
391	ret = in6_pton(addr, len, dst_ib->sib_addr.sib_raw, '\0', NULL);
392	if (ret == 0)
393		return -EINVAL;
394
395	dst_ib->sib_family = AF_IB;
396	/*
397	 * Use the same TCP server port number as the IB service ID
398	 * on the IB port space range
399	 */
400	dst_ib->sib_sid = cpu_to_be64(RDMA_IB_IP_PS_IB | port);
401	dst_ib->sib_sid_mask = cpu_to_be64(0xffffffffffffffffULL);
402	dst_ib->sib_pkey = cpu_to_be16(0xffff);
403
404	return 0;
405}
406
407/**
408 * rtrs_str_to_sockaddr() - Convert rtrs address string to sockaddr
409 * @addr:	String representation of an addr (IPv4, IPv6 or IB GID):
410 *              - "ip:192.168.1.1"
411 *              - "ip:fe80::200:5aee:feaa:20a2"
412 *              - "gid:fe80::200:5aee:feaa:20a2"
413 * @len:        String address length
414 * @port:	Destination port
415 * @dst:	Destination sockaddr structure
416 *
417 * Returns 0 if conversion successful. Non-zero on error.
418 */
419static int rtrs_str_to_sockaddr(const char *addr, size_t len,
420				u16 port, struct sockaddr_storage *dst)
421{
422	if (strncmp(addr, "gid:", 4) == 0) {
423		return rtrs_str_gid_to_sockaddr(addr + 4, len - 4, port, dst);
424	} else if (strncmp(addr, "ip:", 3) == 0) {
425		char port_str[8];
426		char *cpy;
427		int err;
428
429		snprintf(port_str, sizeof(port_str), "%u", port);
430		cpy = kstrndup(addr + 3, len - 3, GFP_KERNEL);
431		err = cpy ? inet_pton_with_scope(&init_net, AF_UNSPEC,
432						 cpy, port_str, dst) : -ENOMEM;
433		kfree(cpy);
434
435		return err;
436	}
437	return -EPROTONOSUPPORT;
438}
439
440/**
441 * sockaddr_to_str() - convert sockaddr to a string.
442 * @addr:	the sockadddr structure to be converted.
443 * @buf:	string containing socket addr.
444 * @len:	string length.
445 *
446 * The return value is the number of characters written into buf not
447 * including the trailing '\0'. If len is == 0 the function returns 0..
448 */
449int sockaddr_to_str(const struct sockaddr *addr, char *buf, size_t len)
450{
451
452	switch (addr->sa_family) {
453	case AF_IB:
454		return scnprintf(buf, len, "gid:%pI6",
455			&((struct sockaddr_ib *)addr)->sib_addr.sib_raw);
456	case AF_INET:
457		return scnprintf(buf, len, "ip:%pI4",
458			&((struct sockaddr_in *)addr)->sin_addr);
459	case AF_INET6:
460		return scnprintf(buf, len, "ip:%pI6c",
461			  &((struct sockaddr_in6 *)addr)->sin6_addr);
462	}
463	return scnprintf(buf, len, "<invalid address family>");
464}
465EXPORT_SYMBOL(sockaddr_to_str);
466
467/**
468 * rtrs_addr_to_sockaddr() - convert path string "src,dst" or "src@dst"
469 * to sockaddreses
470 * @str:	string containing source and destination addr of a path
471 *		separated by ',' or '@' I.e. "ip:1.1.1.1,ip:1.1.1.2" or
472 *		"ip:1.1.1.1@ip:1.1.1.2". If str contains only one address it's
473 *		considered to be destination.
474 * @len:	string length
475 * @port:	Destination port number.
476 * @addr:	will be set to the source/destination address or to NULL
477 *		if str doesn't contain any source address.
478 *
479 * Returns zero if conversion successful. Non-zero otherwise.
480 */
481int rtrs_addr_to_sockaddr(const char *str, size_t len, u16 port,
482			  struct rtrs_addr *addr)
483{
484	const char *d;
485
486	d = strchr(str, ',');
487	if (!d)
488		d = strchr(str, '@');
489	if (d) {
490		if (rtrs_str_to_sockaddr(str, d - str, 0, addr->src))
491			return -EINVAL;
492		d += 1;
493		len -= d - str;
494		str  = d;
495
496	} else {
497		addr->src = NULL;
498	}
499	return rtrs_str_to_sockaddr(str, len, port, addr->dst);
500}
501EXPORT_SYMBOL(rtrs_addr_to_sockaddr);
502
503void rtrs_rdma_dev_pd_init(enum ib_pd_flags pd_flags,
504			    struct rtrs_rdma_dev_pd *pool)
505{
506	WARN_ON(pool->ops && (!pool->ops->alloc ^ !pool->ops->free));
507	INIT_LIST_HEAD(&pool->list);
508	mutex_init(&pool->mutex);
509	pool->pd_flags = pd_flags;
510}
511EXPORT_SYMBOL(rtrs_rdma_dev_pd_init);
512
513void rtrs_rdma_dev_pd_deinit(struct rtrs_rdma_dev_pd *pool)
514{
515	mutex_destroy(&pool->mutex);
516	WARN_ON(!list_empty(&pool->list));
517}
518EXPORT_SYMBOL(rtrs_rdma_dev_pd_deinit);
519
520static void dev_free(struct kref *ref)
521{
522	struct rtrs_rdma_dev_pd *pool;
523	struct rtrs_ib_dev *dev;
524
525	dev = container_of(ref, typeof(*dev), ref);
526	pool = dev->pool;
527
528	mutex_lock(&pool->mutex);
529	list_del(&dev->entry);
530	mutex_unlock(&pool->mutex);
531
532	if (pool->ops && pool->ops->deinit)
533		pool->ops->deinit(dev);
534
535	ib_dealloc_pd(dev->ib_pd);
536
537	if (pool->ops && pool->ops->free)
538		pool->ops->free(dev);
539	else
540		kfree(dev);
541}
542
543int rtrs_ib_dev_put(struct rtrs_ib_dev *dev)
544{
545	return kref_put(&dev->ref, dev_free);
546}
547EXPORT_SYMBOL(rtrs_ib_dev_put);
548
549static int rtrs_ib_dev_get(struct rtrs_ib_dev *dev)
550{
551	return kref_get_unless_zero(&dev->ref);
552}
553
554struct rtrs_ib_dev *
555rtrs_ib_dev_find_or_add(struct ib_device *ib_dev,
556			 struct rtrs_rdma_dev_pd *pool)
557{
558	struct rtrs_ib_dev *dev;
559
560	mutex_lock(&pool->mutex);
561	list_for_each_entry(dev, &pool->list, entry) {
562		if (dev->ib_dev->node_guid == ib_dev->node_guid &&
563		    rtrs_ib_dev_get(dev))
564			goto out_unlock;
565	}
566	mutex_unlock(&pool->mutex);
567	if (pool->ops && pool->ops->alloc)
568		dev = pool->ops->alloc();
569	else
570		dev = kzalloc(sizeof(*dev), GFP_KERNEL);
571	if (IS_ERR_OR_NULL(dev))
572		goto out_err;
573
574	kref_init(&dev->ref);
575	dev->pool = pool;
576	dev->ib_dev = ib_dev;
577	dev->ib_pd = ib_alloc_pd(ib_dev, pool->pd_flags);
578	if (IS_ERR(dev->ib_pd))
579		goto out_free_dev;
580
581	if (pool->ops && pool->ops->init && pool->ops->init(dev))
582		goto out_free_pd;
583
584	mutex_lock(&pool->mutex);
585	list_add(&dev->entry, &pool->list);
586out_unlock:
587	mutex_unlock(&pool->mutex);
588	return dev;
589
590out_free_pd:
591	ib_dealloc_pd(dev->ib_pd);
592out_free_dev:
593	if (pool->ops && pool->ops->free)
594		pool->ops->free(dev);
595	else
596		kfree(dev);
597out_err:
598	return NULL;
599}
600EXPORT_SYMBOL(rtrs_ib_dev_find_or_add);
601