xref: /openbmc/linux/drivers/infiniband/core/addr.c (revision 565d76cb)
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/slab.h>
39 #include <linux/workqueue.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 	dev_addr->dev_type = dev->type;
96 	memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
97 	memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
98 	if (dst_dev_addr)
99 		memcpy(dev_addr->dst_dev_addr, dst_dev_addr, MAX_ADDR_LEN);
100 	dev_addr->bound_dev_if = dev->ifindex;
101 	return 0;
102 }
103 EXPORT_SYMBOL(rdma_copy_addr);
104 
105 int rdma_translate_ip(struct sockaddr *addr, struct rdma_dev_addr *dev_addr)
106 {
107 	struct net_device *dev;
108 	int ret = -EADDRNOTAVAIL;
109 
110 	if (dev_addr->bound_dev_if) {
111 		dev = dev_get_by_index(&init_net, dev_addr->bound_dev_if);
112 		if (!dev)
113 			return -ENODEV;
114 		ret = rdma_copy_addr(dev_addr, dev, NULL);
115 		dev_put(dev);
116 		return ret;
117 	}
118 
119 	switch (addr->sa_family) {
120 	case AF_INET:
121 		dev = ip_dev_find(&init_net,
122 			((struct sockaddr_in *) addr)->sin_addr.s_addr);
123 
124 		if (!dev)
125 			return ret;
126 
127 		ret = rdma_copy_addr(dev_addr, dev, NULL);
128 		dev_put(dev);
129 		break;
130 
131 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
132 	case AF_INET6:
133 		rcu_read_lock();
134 		for_each_netdev_rcu(&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 		rcu_read_unlock();
143 		break;
144 #endif
145 	}
146 	return ret;
147 }
148 EXPORT_SYMBOL(rdma_translate_ip);
149 
150 static void set_timeout(unsigned long time)
151 {
152 	unsigned long delay;
153 
154 	cancel_delayed_work(&work);
155 
156 	delay = time - jiffies;
157 	if ((long)delay <= 0)
158 		delay = 1;
159 
160 	queue_delayed_work(addr_wq, &work, delay);
161 }
162 
163 static void queue_req(struct addr_req *req)
164 {
165 	struct addr_req *temp_req;
166 
167 	mutex_lock(&lock);
168 	list_for_each_entry_reverse(temp_req, &req_list, list) {
169 		if (time_after_eq(req->timeout, temp_req->timeout))
170 			break;
171 	}
172 
173 	list_add(&req->list, &temp_req->list);
174 
175 	if (req_list.next == &req->list)
176 		set_timeout(req->timeout);
177 	mutex_unlock(&lock);
178 }
179 
180 static int addr4_resolve(struct sockaddr_in *src_in,
181 			 struct sockaddr_in *dst_in,
182 			 struct rdma_dev_addr *addr)
183 {
184 	__be32 src_ip = src_in->sin_addr.s_addr;
185 	__be32 dst_ip = dst_in->sin_addr.s_addr;
186 	struct rtable *rt;
187 	struct neighbour *neigh;
188 	int ret;
189 
190 	rt = ip_route_output(&init_net, dst_ip, src_ip, 0, addr->bound_dev_if);
191 	if (IS_ERR(rt)) {
192 		ret = PTR_ERR(rt);
193 		goto out;
194 	}
195 	src_in->sin_family = AF_INET;
196 	src_in->sin_addr.s_addr = rt->rt_src;
197 
198 	if (rt->dst.dev->flags & IFF_LOOPBACK) {
199 		ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
200 		if (!ret)
201 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
202 		goto put;
203 	}
204 
205 	/* If the device does ARP internally, return 'done' */
206 	if (rt->dst.dev->flags & IFF_NOARP) {
207 		rdma_copy_addr(addr, rt->dst.dev, NULL);
208 		goto put;
209 	}
210 
211 	neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->dst.dev);
212 	if (!neigh || !(neigh->nud_state & NUD_VALID)) {
213 		neigh_event_send(rt->dst.neighbour, NULL);
214 		ret = -ENODATA;
215 		if (neigh)
216 			goto release;
217 		goto put;
218 	}
219 
220 	ret = rdma_copy_addr(addr, neigh->dev, neigh->ha);
221 release:
222 	neigh_release(neigh);
223 put:
224 	ip_rt_put(rt);
225 out:
226 	return ret;
227 }
228 
229 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
230 static int addr6_resolve(struct sockaddr_in6 *src_in,
231 			 struct sockaddr_in6 *dst_in,
232 			 struct rdma_dev_addr *addr)
233 {
234 	struct flowi6 fl6;
235 	struct neighbour *neigh;
236 	struct dst_entry *dst;
237 	int ret;
238 
239 	memset(&fl6, 0, sizeof fl6);
240 	ipv6_addr_copy(&fl6.daddr, &dst_in->sin6_addr);
241 	ipv6_addr_copy(&fl6.saddr, &src_in->sin6_addr);
242 	fl6.flowi6_oif = addr->bound_dev_if;
243 
244 	dst = ip6_route_output(&init_net, NULL, &fl6);
245 	if ((ret = dst->error))
246 		goto put;
247 
248 	if (ipv6_addr_any(&fl6.saddr)) {
249 		ret = ipv6_dev_get_saddr(&init_net, ip6_dst_idev(dst)->dev,
250 					 &fl6.daddr, 0, &fl6.saddr);
251 		if (ret)
252 			goto put;
253 
254 		src_in->sin6_family = AF_INET6;
255 		ipv6_addr_copy(&src_in->sin6_addr, &fl6.saddr);
256 	}
257 
258 	if (dst->dev->flags & IFF_LOOPBACK) {
259 		ret = rdma_translate_ip((struct sockaddr *) dst_in, addr);
260 		if (!ret)
261 			memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
262 		goto put;
263 	}
264 
265 	/* If the device does ARP internally, return 'done' */
266 	if (dst->dev->flags & IFF_NOARP) {
267 		ret = rdma_copy_addr(addr, dst->dev, NULL);
268 		goto put;
269 	}
270 
271 	neigh = dst->neighbour;
272 	if (!neigh || !(neigh->nud_state & NUD_VALID)) {
273 		neigh_event_send(dst->neighbour, NULL);
274 		ret = -ENODATA;
275 		goto put;
276 	}
277 
278 	ret = rdma_copy_addr(addr, dst->dev, neigh->ha);
279 put:
280 	dst_release(dst);
281 	return ret;
282 }
283 #else
284 static int addr6_resolve(struct sockaddr_in6 *src_in,
285 			 struct sockaddr_in6 *dst_in,
286 			 struct rdma_dev_addr *addr)
287 {
288 	return -EADDRNOTAVAIL;
289 }
290 #endif
291 
292 static int addr_resolve(struct sockaddr *src_in,
293 			struct sockaddr *dst_in,
294 			struct rdma_dev_addr *addr)
295 {
296 	if (src_in->sa_family == AF_INET) {
297 		return addr4_resolve((struct sockaddr_in *) src_in,
298 			(struct sockaddr_in *) dst_in, addr);
299 	} else
300 		return addr6_resolve((struct sockaddr_in6 *) src_in,
301 			(struct sockaddr_in6 *) dst_in, addr);
302 }
303 
304 static void process_req(struct work_struct *work)
305 {
306 	struct addr_req *req, *temp_req;
307 	struct sockaddr *src_in, *dst_in;
308 	struct list_head done_list;
309 
310 	INIT_LIST_HEAD(&done_list);
311 
312 	mutex_lock(&lock);
313 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
314 		if (req->status == -ENODATA) {
315 			src_in = (struct sockaddr *) &req->src_addr;
316 			dst_in = (struct sockaddr *) &req->dst_addr;
317 			req->status = addr_resolve(src_in, dst_in, req->addr);
318 			if (req->status && time_after_eq(jiffies, req->timeout))
319 				req->status = -ETIMEDOUT;
320 			else if (req->status == -ENODATA)
321 				continue;
322 		}
323 		list_move_tail(&req->list, &done_list);
324 	}
325 
326 	if (!list_empty(&req_list)) {
327 		req = list_entry(req_list.next, struct addr_req, list);
328 		set_timeout(req->timeout);
329 	}
330 	mutex_unlock(&lock);
331 
332 	list_for_each_entry_safe(req, temp_req, &done_list, list) {
333 		list_del(&req->list);
334 		req->callback(req->status, (struct sockaddr *) &req->src_addr,
335 			req->addr, req->context);
336 		put_client(req->client);
337 		kfree(req);
338 	}
339 }
340 
341 int rdma_resolve_ip(struct rdma_addr_client *client,
342 		    struct sockaddr *src_addr, struct sockaddr *dst_addr,
343 		    struct rdma_dev_addr *addr, int timeout_ms,
344 		    void (*callback)(int status, struct sockaddr *src_addr,
345 				     struct rdma_dev_addr *addr, void *context),
346 		    void *context)
347 {
348 	struct sockaddr *src_in, *dst_in;
349 	struct addr_req *req;
350 	int ret = 0;
351 
352 	req = kzalloc(sizeof *req, GFP_KERNEL);
353 	if (!req)
354 		return -ENOMEM;
355 
356 	src_in = (struct sockaddr *) &req->src_addr;
357 	dst_in = (struct sockaddr *) &req->dst_addr;
358 
359 	if (src_addr) {
360 		if (src_addr->sa_family != dst_addr->sa_family) {
361 			ret = -EINVAL;
362 			goto err;
363 		}
364 
365 		memcpy(src_in, src_addr, ip_addr_size(src_addr));
366 	} else {
367 		src_in->sa_family = dst_addr->sa_family;
368 	}
369 
370 	memcpy(dst_in, dst_addr, ip_addr_size(dst_addr));
371 	req->addr = addr;
372 	req->callback = callback;
373 	req->context = context;
374 	req->client = client;
375 	atomic_inc(&client->refcount);
376 
377 	req->status = addr_resolve(src_in, dst_in, addr);
378 	switch (req->status) {
379 	case 0:
380 		req->timeout = jiffies;
381 		queue_req(req);
382 		break;
383 	case -ENODATA:
384 		req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
385 		queue_req(req);
386 		break;
387 	default:
388 		ret = req->status;
389 		atomic_dec(&client->refcount);
390 		goto err;
391 	}
392 	return ret;
393 err:
394 	kfree(req);
395 	return ret;
396 }
397 EXPORT_SYMBOL(rdma_resolve_ip);
398 
399 void rdma_addr_cancel(struct rdma_dev_addr *addr)
400 {
401 	struct addr_req *req, *temp_req;
402 
403 	mutex_lock(&lock);
404 	list_for_each_entry_safe(req, temp_req, &req_list, list) {
405 		if (req->addr == addr) {
406 			req->status = -ECANCELED;
407 			req->timeout = jiffies;
408 			list_move(&req->list, &req_list);
409 			set_timeout(req->timeout);
410 			break;
411 		}
412 	}
413 	mutex_unlock(&lock);
414 }
415 EXPORT_SYMBOL(rdma_addr_cancel);
416 
417 static int netevent_callback(struct notifier_block *self, unsigned long event,
418 	void *ctx)
419 {
420 	if (event == NETEVENT_NEIGH_UPDATE) {
421 		struct neighbour *neigh = ctx;
422 
423 		if (neigh->nud_state & NUD_VALID) {
424 			set_timeout(jiffies);
425 		}
426 	}
427 	return 0;
428 }
429 
430 static struct notifier_block nb = {
431 	.notifier_call = netevent_callback
432 };
433 
434 static int __init addr_init(void)
435 {
436 	addr_wq = create_singlethread_workqueue("ib_addr");
437 	if (!addr_wq)
438 		return -ENOMEM;
439 
440 	register_netevent_notifier(&nb);
441 	return 0;
442 }
443 
444 static void __exit addr_cleanup(void)
445 {
446 	unregister_netevent_notifier(&nb);
447 	destroy_workqueue(addr_wq);
448 }
449 
450 module_init(addr_init);
451 module_exit(addr_cleanup);
452