xref: /openbmc/linux/drivers/infiniband/core/addr.c (revision e8e0929d)
1 /*
2  * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
3  * Copyright (c) 2002-2005, Network Appliance, Inc. All rights reserved.
4  * Copyright (c) 1999-2005, Mellanox Technologies, Inc. All rights reserved.
5  * Copyright (c) 2005 Intel Corporation.  All rights reserved.
6  *
7  * This software is available to you under a choice of one of two
8  * licenses.  You may choose to be licensed under the terms of the GNU
9  * General Public License (GPL) Version 2, available from the file
10  * COPYING in the main directory of this source tree, or the
11  * OpenIB.org BSD license below:
12  *
13  *     Redistribution and use in source and binary forms, with or
14  *     without modification, are permitted provided that the following
15  *     conditions are met:
16  *
17  *      - Redistributions of source code must retain the above
18  *        copyright notice, this list of conditions and the following
19  *        disclaimer.
20  *
21  *      - Redistributions in binary form must reproduce the above
22  *        copyright notice, this list of conditions and the following
23  *        disclaimer in the documentation and/or other materials
24  *        provided with the distribution.
25  *
26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
27  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
28  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
29  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
30  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
31  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
32  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33  * SOFTWARE.
34  */
35 
36 #include <linux/mutex.h>
37 #include <linux/inetdevice.h>
38 #include <linux/workqueue.h>
39 #include <linux/if_arp.h>
40 #include <net/arp.h>
41 #include <net/neighbour.h>
42 #include <net/route.h>
43 #include <net/netevent.h>
44 #include <net/addrconf.h>
45 #include <net/ip6_route.h>
46 #include <rdma/ib_addr.h>
47 
48 MODULE_AUTHOR("Sean Hefty");
49 MODULE_DESCRIPTION("IB Address Translation");
50 MODULE_LICENSE("Dual BSD/GPL");
51 
52 struct addr_req {
53 	struct list_head list;
54 	struct sockaddr_storage src_addr;
55 	struct sockaddr_storage dst_addr;
56 	struct rdma_dev_addr *addr;
57 	struct rdma_addr_client *client;
58 	void *context;
59 	void (*callback)(int status, struct sockaddr *src_addr,
60 			 struct rdma_dev_addr *addr, void *context);
61 	unsigned long timeout;
62 	int status;
63 };
64 
65 static void process_req(struct work_struct *work);
66 
67 static DEFINE_MUTEX(lock);
68 static LIST_HEAD(req_list);
69 static DECLARE_DELAYED_WORK(work, process_req);
70 static struct workqueue_struct *addr_wq;
71 
72 void rdma_addr_register_client(struct rdma_addr_client *client)
73 {
74 	atomic_set(&client->refcount, 1);
75 	init_completion(&client->comp);
76 }
77 EXPORT_SYMBOL(rdma_addr_register_client);
78 
79 static inline void put_client(struct rdma_addr_client *client)
80 {
81 	if (atomic_dec_and_test(&client->refcount))
82 		complete(&client->comp);
83 }
84 
85 void rdma_addr_unregister_client(struct rdma_addr_client *client)
86 {
87 	put_client(client);
88 	wait_for_completion(&client->comp);
89 }
90 EXPORT_SYMBOL(rdma_addr_unregister_client);
91 
92 int rdma_copy_addr(struct rdma_dev_addr *dev_addr, struct net_device *dev,
93 		     const unsigned char *dst_dev_addr)
94 {
95 	switch (dev->type) {
96 	case ARPHRD_INFINIBAND:
97 		dev_addr->dev_type = RDMA_NODE_IB_CA;
98 		break;
99 	case ARPHRD_ETHER:
100 		dev_addr->dev_type = RDMA_NODE_RNIC;
101 		break;
102 	default:
103 		return -EADDRNOTAVAIL;
104 	}
105 
106 	memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
107 	memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
108 	if (dst_dev_addr)
109 		memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
110 	dev_addr->src_dev = dev;
111 	return 0;
112 }
113 EXPORT_SYMBOL(rdma_copy_addr);
114 
115 int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
116 {
117 	struct net_device *dev;
118 	int ret = -EADDRNOTAVAIL;
119 
120 	switch (addr->sa_family) {
121 	case AF_INET:
122 		dev = ip_dev_find(&init_net,
123 			((struct sockaddr_in *) addr)->sin_addr.s_addr);
124 
125 		if (!dev)
126 			return ret;
127 
128 		ret = rdma_copy_addr(dev_addr, dev, NULL);
129 		dev_put(dev);
130 		break;
131 
132 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
133 	case AF_INET6:
134 		for_each_netdev(&init_net, dev) {
135 			if (ipv6_chk_addr(&init_net,
136 					  &((struct sockaddr_in6 *) addr)->sin6_addr,
137 					  dev, 1)) {
138 				ret = rdma_copy_addr(dev_addr, dev, NULL);
139 				break;
140 			}
141 		}
142 		break;
143 #endif
144 	}
145 	return ret;
146 }
147 EXPORT_SYMBOL(rdma_translate_ip);
148 
149 static void set_timeout(unsigned long time)
150 {
151 	unsigned long delay;
152 
153 	cancel_delayed_work(&work);
154 
155 	delay = time - jiffies;
156 	if ((long)delay <= 0)
157 		delay = 1;
158 
159 	queue_delayed_work(addr_wq, &work, delay);
160 }
161 
162 static void queue_req(struct addr_req *req)
163 {
164 	struct addr_req *temp_req;
165 
166 	mutex_lock(&lock);
167 	list_for_each_entry_reverse(temp_req, &req_list, list) {
168 		if (time_after_eq(req->timeout, temp_req->timeout))
169 			break;
170 	}
171 
172 	list_add(&req->list, &temp_req->list);
173 
174 	if (req_list.next == &req->list)
175 		set_timeout(req->timeout);
176 	mutex_unlock(&lock);
177 }
178 
179 static void addr_send_arp(struct sockaddr *dst_in)
180 {
181 	struct rtable *rt;
182 	struct flowi fl;
183 
184 	memset(&fl, 0, sizeof fl);
185 
186 	switch (dst_in->sa_family) {
187 	case AF_INET:
188 		fl.nl_u.ip4_u.daddr =
189 			((struct sockaddr_in *) dst_in)->sin_addr.s_addr;
190 
191 		if (ip_route_output_key(&init_net, &rt, &fl))
192 			return;
193 
194 		neigh_event_send(rt->u.dst.neighbour, NULL);
195 		ip_rt_put(rt);
196 		break;
197 
198 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
199 	case AF_INET6:
200 	{
201 		struct dst_entry *dst;
202 
203 		fl.nl_u.ip6_u.daddr =
204 			((struct sockaddr_in6 *) dst_in)->sin6_addr;
205 
206 		dst = ip6_route_output(&init_net, NULL, &fl);
207 		if (!dst)
208 			return;
209 
210 		neigh_event_send(dst->neighbour, NULL);
211 		dst_release(dst);
212 		break;
213 	}
214 #endif
215 	}
216 }
217 
218 static int addr4_resolve_remote(struct sockaddr_in *src_in,
219 			       struct sockaddr_in *dst_in,
220 			       struct rdma_dev_addr *addr)
221 {
222 	__be32 src_ip = src_in->sin_addr.s_addr;
223 	__be32 dst_ip = dst_in->sin_addr.s_addr;
224 	struct flowi fl;
225 	struct rtable *rt;
226 	struct neighbour *neigh;
227 	int ret;
228 
229 	memset(&fl, 0, sizeof fl);
230 	fl.nl_u.ip4_u.daddr = dst_ip;
231 	fl.nl_u.ip4_u.saddr = src_ip;
232 	ret = ip_route_output_key(&init_net, &rt, &fl);
233 	if (ret)
234 		goto out;
235 
236 	/* If the device does ARP internally, return 'done' */
237 	if (rt->idev->dev->flags & IFF_NOARP) {
238 		rdma_copy_addr(addr, rt->idev->dev, NULL);
239 		goto put;
240 	}
241 
242 	neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->idev->dev);
243 	if (!neigh) {
244 		ret = -ENODATA;
245 		goto put;
246 	}
247 
248 	if (!(neigh->nud_state & NUD_VALID)) {
249 		ret = -ENODATA;
250 		goto release;
251 	}
252 
253 	if (!src_ip) {
254 		src_in->sin_family = dst_in->sin_family;
255 		src_in->sin_addr.s_addr = rt->rt_src;
256 	}
257 
258 	ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
259 release:
260 	neigh_release(neigh);
261 put:
262 	ip_rt_put(rt);
263 out:
264 	return ret;
265 }
266 
267 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
268 static int addr6_resolve_remote(struct sockaddr_in6 *src_in,
269 			       struct sockaddr_in6 *dst_in,
270 			       struct rdma_dev_addr *addr)
271 {
272 	struct flowi fl;
273 	struct neighbour *neigh;
274 	struct dst_entry *dst;
275 	int ret = -ENODATA;
276 
277 	memset(&fl, 0, sizeof fl);
278 	fl.nl_u.ip6_u.daddr = dst_in->sin6_addr;
279 	fl.nl_u.ip6_u.saddr = src_in->sin6_addr;
280 
281 	dst = ip6_route_output(&init_net, NULL, &fl);
282 	if (!dst)
283 		return ret;
284 
285 	if (dst->dev->flags & IFF_NOARP) {
286 		ret = rdma_copy_addr(addr, dst->dev, NULL);
287 	} else {
288 		neigh = dst->neighbour;
289 		if (neigh && (neigh->nud_state & NUD_VALID))
290 			ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
291 	}
292 
293 	dst_release(dst);
294 	return ret;
295 }
296 #else
297 static int addr6_resolve_remote(struct sockaddr_in6 *src_in,
298 			       struct sockaddr_in6 *dst_in,
299 			       struct rdma_dev_addr *addr)
300 {
301 	return -EADDRNOTAVAIL;
302 }
303 #endif
304 
305 static int addr_resolve_remote(struct sockaddr *src_in,
306 				struct sockaddr *dst_in,
307 				struct rdma_dev_addr *addr)
308 {
309 	if (src_in->sa_family == AF_INET) {
310 		return addr4_resolve_remote((struct sockaddr_in *) src_in,
311 			(struct sockaddr_in *) dst_in, addr);
312 	} else
313 		return addr6_resolve_remote((struct sockaddr_in6 *) src_in,
314 			(struct sockaddr_in6 *) dst_in, addr);
315 }
316 
317 static void process_req(struct work_struct *work)
318 {
319 	struct addr_req *req, *temp_req;
320 	struct sockaddr *src_in, *dst_in;
321 	struct list_head done_list;
322 
323 	INIT_LIST_HEAD(&done_list);
324 
325 	mutex_lock(&lock);
326 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
327 		if (req->status == -ENODATA) {
328 			src_in = (struct sockaddr *) &req->src_addr;
329 			dst_in = (struct sockaddr *) &req->dst_addr;
330 			req->status = addr_resolve_remote(src_in, dst_in,
331 							  req->addr);
332 			if (req->status && time_after_eq(jiffies, req->timeout))
333 				req->status = -ETIMEDOUT;
334 			else if (req->status == -ENODATA)
335 				continue;
336 		}
337 		list_move_tail(&req->list, &done_list);
338 	}
339 
340 	if (!list_empty(&req_list)) {
341 		req = list_entry(req_list.next, struct addr_req, list);
342 		set_timeout(req->timeout);
343 	}
344 	mutex_unlock(&lock);
345 
346 	list_for_each_entry_safe(req, temp_req, &done_list, list) {
347 		list_del(&req->list);
348 		req->callback(req->status, (struct sockaddr *) &req->src_addr,
349 			req->addr, req->context);
350 		put_client(req->client);
351 		kfree(req);
352 	}
353 }
354 
355 static int addr_resolve_local(struct sockaddr *src_in,
356 			      struct sockaddr *dst_in,
357 			      struct rdma_dev_addr *addr)
358 {
359 	struct net_device *dev;
360 	int ret;
361 
362 	switch (dst_in->sa_family) {
363 	case AF_INET:
364 	{
365 		__be32 src_ip = ((struct sockaddr_in *) src_in)->sin_addr.s_addr;
366 		__be32 dst_ip = ((struct sockaddr_in *) dst_in)->sin_addr.s_addr;
367 
368 		dev = ip_dev_find(&init_net, dst_ip);
369 		if (!dev)
370 			return -EADDRNOTAVAIL;
371 
372 		if (ipv4_is_zeronet(src_ip)) {
373 			src_in->sa_family = dst_in->sa_family;
374 			((struct sockaddr_in *) src_in)->sin_addr.s_addr = dst_ip;
375 			ret = rdma_copy_addr(addr, dev, dev->dev_addr);
376 		} else if (ipv4_is_loopback(src_ip)) {
377 			ret = rdma_translate_ip(dst_in, addr);
378 			if (!ret)
379 				memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
380 		} else {
381 			ret = rdma_translate_ip(src_in, addr);
382 			if (!ret)
383 				memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
384 		}
385 		dev_put(dev);
386 		break;
387 	}
388 
389 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
390 	case AF_INET6:
391 	{
392 		struct in6_addr *a;
393 
394 		for_each_netdev(&init_net, dev)
395 			if (ipv6_chk_addr(&init_net,
396 					  &((struct sockaddr_in6 *) addr)->sin6_addr,
397 					  dev, 1))
398 				break;
399 
400 		if (!dev)
401 			return -EADDRNOTAVAIL;
402 
403 		a = &((struct sockaddr_in6 *) src_in)->sin6_addr;
404 
405 		if (ipv6_addr_any(a)) {
406 			src_in->sa_family = dst_in->sa_family;
407 			((struct sockaddr_in6 *) src_in)->sin6_addr =
408 				((struct sockaddr_in6 *) dst_in)->sin6_addr;
409 			ret = rdma_copy_addr(addr, dev, dev->dev_addr);
410 		} else if (ipv6_addr_loopback(a)) {
411 			ret = rdma_translate_ip(dst_in, addr);
412 			if (!ret)
413 				memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
414 		} else  {
415 			ret = rdma_translate_ip(src_in, addr);
416 			if (!ret)
417 				memcpy(addr->dst_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
418 		}
419 		break;
420 	}
421 #endif
422 
423 	default:
424 		ret = -EADDRNOTAVAIL;
425 		break;
426 	}
427 
428 	return ret;
429 }
430 
431 int rdma_resolve_ip(struct rdma_addr_client *client,
432 		    struct sockaddr *src_addr, struct sockaddr *dst_addr,
433 		    struct rdma_dev_addr *addr, int timeout_ms,
434 		    void (*callback)(int status, struct sockaddr *src_addr,
435 				     struct rdma_dev_addr *addr, void *context),
436 		    void *context)
437 {
438 	struct sockaddr *src_in, *dst_in;
439 	struct addr_req *req;
440 	int ret = 0;
441 
442 	req = kzalloc(sizeof *req, GFP_KERNEL);
443 	if (!req)
444 		return -ENOMEM;
445 
446 	if (src_addr)
447 		memcpy(&req->src_addr, src_addr, ip_addr_size(src_addr));
448 	memcpy(&req->dst_addr, dst_addr, ip_addr_size(dst_addr));
449 	req->addr = addr;
450 	req->callback = callback;
451 	req->context = context;
452 	req->client = client;
453 	atomic_inc(&client->refcount);
454 
455 	src_in = (struct sockaddr *) &req->src_addr;
456 	dst_in = (struct sockaddr *) &req->dst_addr;
457 
458 	req->status = addr_resolve_local(src_in, dst_in, addr);
459 	if (req->status == -EADDRNOTAVAIL)
460 		req->status = addr_resolve_remote(src_in, dst_in, addr);
461 
462 	switch (req->status) {
463 	case 0:
464 		req->timeout = jiffies;
465 		queue_req(req);
466 		break;
467 	case -ENODATA:
468 		req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
469 		queue_req(req);
470 		addr_send_arp(dst_in);
471 		break;
472 	default:
473 		ret = req->status;
474 		atomic_dec(&client->refcount);
475 		kfree(req);
476 		break;
477 	}
478 	return ret;
479 }
480 EXPORT_SYMBOL(rdma_resolve_ip);
481 
482 void rdma_addr_cancel(struct rdma_dev_addr *addr)
483 {
484 	struct addr_req *req, *temp_req;
485 
486 	mutex_lock(&lock);
487 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
488 		if (req->addr == addr) {
489 			req->status = -ECANCELED;
490 			req->timeout = jiffies;
491 			list_move(&req->list, &req_list);
492 			set_timeout(req->timeout);
493 			break;
494 		}
495 	}
496 	mutex_unlock(&lock);
497 }
498 EXPORT_SYMBOL(rdma_addr_cancel);
499 
500 static int netevent_callback(struct notifier_block *self, unsigned long event,
501 	void *ctx)
502 {
503 	if (event == NETEVENT_NEIGH_UPDATE) {
504 		struct neighbour *neigh = ctx;
505 
506 		if (neigh->nud_state & NUD_VALID) {
507 			set_timeout(jiffies);
508 		}
509 	}
510 	return 0;
511 }
512 
513 static struct notifier_block nb = {
514 	.notifier_call = netevent_callback
515 };
516 
517 static int __init addr_init(void)
518 {
519 	addr_wq = create_singlethread_workqueue("ib_addr");
520 	if (!addr_wq)
521 		return -ENOMEM;
522 
523 	register_netevent_notifier(&nb);
524 	return 0;
525 }
526 
527 static void __exit addr_cleanup(void)
528 {
529 	unregister_netevent_notifier(&nb);
530 	destroy_workqueue(addr_wq);
531 }
532 
533 module_init(addr_init);
534 module_exit(addr_cleanup);
535