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/ipv6_stubs.h>
 45#include <net/ip6_route.h>
 46#include <rdma/ib_addr.h>
 47#include <rdma/ib_cache.h>
 48#include <rdma/ib_sa.h>
 49#include <rdma/ib.h>
 50#include <rdma/rdma_netlink.h>
 51#include <net/netlink.h>
 52
 53#include "core_priv.h"
 54
 55struct addr_req {
 56	struct list_head list;
 57	struct sockaddr_storage src_addr;
 58	struct sockaddr_storage dst_addr;
 59	struct rdma_dev_addr *addr;
 60	void *context;
 61	void (*callback)(int status, struct sockaddr *src_addr,
 62			 struct rdma_dev_addr *addr, void *context);
 63	unsigned long timeout;
 64	struct delayed_work work;
 65	bool resolve_by_gid_attr;	/* Consider gid attr in resolve phase */
 66	int status;
 67	u32 seq;
 68};
 69
 70static atomic_t ib_nl_addr_request_seq = ATOMIC_INIT(0);
 71
 72static DEFINE_SPINLOCK(lock);
 73static LIST_HEAD(req_list);
 74static struct workqueue_struct *addr_wq;
 75
 76static const struct nla_policy ib_nl_addr_policy[LS_NLA_TYPE_MAX] = {
 77	[LS_NLA_TYPE_DGID] = {.type = NLA_BINARY,
 78		.len = sizeof(struct rdma_nla_ls_gid),
 79		.validation_type = NLA_VALIDATE_MIN,
 80		.min = sizeof(struct rdma_nla_ls_gid)},
 81};
 82
 83static inline bool ib_nl_is_good_ip_resp(const struct nlmsghdr *nlh)
 84{
 85	struct nlattr *tb[LS_NLA_TYPE_MAX] = {};
 86	int ret;
 87
 88	if (nlh->nlmsg_flags & RDMA_NL_LS_F_ERR)
 89		return false;
 90
 91	ret = nla_parse_deprecated(tb, LS_NLA_TYPE_MAX - 1, nlmsg_data(nlh),
 92				   nlmsg_len(nlh), ib_nl_addr_policy, NULL);
 93	if (ret)
 94		return false;
 95
 96	return true;
 97}
 98
 99static void ib_nl_process_good_ip_rsep(const struct nlmsghdr *nlh)
100{
101	const struct nlattr *head, *curr;
102	union ib_gid gid;
103	struct addr_req *req;
104	int len, rem;
105	int found = 0;
106
107	head = (const struct nlattr *)nlmsg_data(nlh);
108	len = nlmsg_len(nlh);
109
110	nla_for_each_attr(curr, head, len, rem) {
111		if (curr->nla_type == LS_NLA_TYPE_DGID)
112			memcpy(&gid, nla_data(curr), nla_len(curr));
113	}
114
115	spin_lock_bh(&lock);
116	list_for_each_entry(req, &req_list, list) {
117		if (nlh->nlmsg_seq != req->seq)
118			continue;
119		/* We set the DGID part, the rest was set earlier */
120		rdma_addr_set_dgid(req->addr, &gid);
121		req->status = 0;
122		found = 1;
123		break;
124	}
125	spin_unlock_bh(&lock);
126
127	if (!found)
128		pr_info("Couldn't find request waiting for DGID: %pI6\n",
129			&gid);
130}
131
132int ib_nl_handle_ip_res_resp(struct sk_buff *skb,
133			     struct nlmsghdr *nlh,
134			     struct netlink_ext_ack *extack)
135{
136	if ((nlh->nlmsg_flags & NLM_F_REQUEST) ||
137	    !(NETLINK_CB(skb).sk))
138		return -EPERM;
139
140	if (ib_nl_is_good_ip_resp(nlh))
141		ib_nl_process_good_ip_rsep(nlh);
142
143	return 0;
144}
145
146static int ib_nl_ip_send_msg(struct rdma_dev_addr *dev_addr,
147			     const void *daddr,
148			     u32 seq, u16 family)
149{
150	struct sk_buff *skb = NULL;
151	struct nlmsghdr *nlh;
152	struct rdma_ls_ip_resolve_header *header;
153	void *data;
154	size_t size;
155	int attrtype;
156	int len;
157
158	if (family == AF_INET) {
159		size = sizeof(struct in_addr);
160		attrtype = RDMA_NLA_F_MANDATORY | LS_NLA_TYPE_IPV4;
161	} else {
162		size = sizeof(struct in6_addr);
163		attrtype = RDMA_NLA_F_MANDATORY | LS_NLA_TYPE_IPV6;
164	}
165
166	len = nla_total_size(sizeof(size));
167	len += NLMSG_ALIGN(sizeof(*header));
168
169	skb = nlmsg_new(len, GFP_KERNEL);
170	if (!skb)
171		return -ENOMEM;
172
173	data = ibnl_put_msg(skb, &nlh, seq, 0, RDMA_NL_LS,
174			    RDMA_NL_LS_OP_IP_RESOLVE, NLM_F_REQUEST);
175	if (!data) {
176		nlmsg_free(skb);
177		return -ENODATA;
178	}
179
180	/* Construct the family header first */
181	header = skb_put(skb, NLMSG_ALIGN(sizeof(*header)));
182	header->ifindex = dev_addr->bound_dev_if;
183	nla_put(skb, attrtype, size, daddr);
184
185	/* Repair the nlmsg header length */
186	nlmsg_end(skb, nlh);
187	rdma_nl_multicast(&init_net, skb, RDMA_NL_GROUP_LS, GFP_KERNEL);
188
189	/* Make the request retry, so when we get the response from userspace
190	 * we will have something.
191	 */
192	return -ENODATA;
193}
194
195int rdma_addr_size(const struct sockaddr *addr)
196{
197	switch (addr->sa_family) {
198	case AF_INET:
199		return sizeof(struct sockaddr_in);
200	case AF_INET6:
201		return sizeof(struct sockaddr_in6);
202	case AF_IB:
203		return sizeof(struct sockaddr_ib);
204	default:
205		return 0;
206	}
207}
208EXPORT_SYMBOL(rdma_addr_size);
209
210int rdma_addr_size_in6(struct sockaddr_in6 *addr)
211{
212	int ret = rdma_addr_size((struct sockaddr *) addr);
213
214	return ret <= sizeof(*addr) ? ret : 0;
215}
216EXPORT_SYMBOL(rdma_addr_size_in6);
217
218int rdma_addr_size_kss(struct __kernel_sockaddr_storage *addr)
219{
220	int ret = rdma_addr_size((struct sockaddr *) addr);
221
222	return ret <= sizeof(*addr) ? ret : 0;
223}
224EXPORT_SYMBOL(rdma_addr_size_kss);
225
226/**
227 * rdma_copy_src_l2_addr - Copy netdevice source addresses
228 * @dev_addr:	Destination address pointer where to copy the addresses
229 * @dev:	Netdevice whose source addresses to copy
230 *
231 * rdma_copy_src_l2_addr() copies source addresses from the specified netdevice.
232 * This includes unicast address, broadcast address, device type and
233 * interface index.
234 */
235void rdma_copy_src_l2_addr(struct rdma_dev_addr *dev_addr,
236			   const struct net_device *dev)
237{
238	dev_addr->dev_type = dev->type;
239	memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
240	memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
241	dev_addr->bound_dev_if = dev->ifindex;
242}
243EXPORT_SYMBOL(rdma_copy_src_l2_addr);
244
245static struct net_device *
246rdma_find_ndev_for_src_ip_rcu(struct net *net, const struct sockaddr *src_in)
247{
248	struct net_device *dev = NULL;
249	int ret = -EADDRNOTAVAIL;
250
251	switch (src_in->sa_family) {
252	case AF_INET:
253		dev = __ip_dev_find(net,
254				    ((const struct sockaddr_in *)src_in)->sin_addr.s_addr,
255				    false);
256		if (dev)
257			ret = 0;
258		break;
259#if IS_ENABLED(CONFIG_IPV6)
260	case AF_INET6:
261		for_each_netdev_rcu(net, dev) {
262			if (ipv6_chk_addr(net,
263					  &((const struct sockaddr_in6 *)src_in)->sin6_addr,
264					  dev, 1)) {
265				ret = 0;
266				break;
267			}
268		}
269		break;
270#endif
271	}
272	return ret ? ERR_PTR(ret) : dev;
273}
274
275int rdma_translate_ip(const struct sockaddr *addr,
276		      struct rdma_dev_addr *dev_addr)
277{
278	struct net_device *dev;
279
280	if (dev_addr->bound_dev_if) {
281		dev = dev_get_by_index(dev_addr->net, dev_addr->bound_dev_if);
282		if (!dev)
283			return -ENODEV;
284		rdma_copy_src_l2_addr(dev_addr, dev);
285		dev_put(dev);
286		return 0;
287	}
288
289	rcu_read_lock();
290	dev = rdma_find_ndev_for_src_ip_rcu(dev_addr->net, addr);
291	if (!IS_ERR(dev))
292		rdma_copy_src_l2_addr(dev_addr, dev);
293	rcu_read_unlock();
294	return PTR_ERR_OR_ZERO(dev);
295}
296EXPORT_SYMBOL(rdma_translate_ip);
297
298static void set_timeout(struct addr_req *req, unsigned long time)
299{
300	unsigned long delay;
301
302	delay = time - jiffies;
303	if ((long)delay < 0)
304		delay = 0;
305
306	mod_delayed_work(addr_wq, &req->work, delay);
307}
308
309static void queue_req(struct addr_req *req)
310{
311	spin_lock_bh(&lock);
312	list_add_tail(&req->list, &req_list);
313	set_timeout(req, req->timeout);
314	spin_unlock_bh(&lock);
315}
316
317static int ib_nl_fetch_ha(struct rdma_dev_addr *dev_addr,
318			  const void *daddr, u32 seq, u16 family)
319{
320	if (!rdma_nl_chk_listeners(RDMA_NL_GROUP_LS))
321		return -EADDRNOTAVAIL;
322
323	return ib_nl_ip_send_msg(dev_addr, daddr, seq, family);
324}
325
326static int dst_fetch_ha(const struct dst_entry *dst,
327			struct rdma_dev_addr *dev_addr,
328			const void *daddr)
329{
330	struct neighbour *n;
331	int ret = 0;
332
333	n = dst_neigh_lookup(dst, daddr);
334	if (!n)
335		return -ENODATA;
336
337	if (!(n->nud_state & NUD_VALID)) {
338		neigh_event_send(n, NULL);
339		ret = -ENODATA;
340	} else {
341		neigh_ha_snapshot(dev_addr->dst_dev_addr, n, dst->dev);
342	}
343
344	neigh_release(n);
345
346	return ret;
347}
348
349static bool has_gateway(const struct dst_entry *dst, sa_family_t family)
350{
351	struct rtable *rt;
352	struct rt6_info *rt6;
353
354	if (family == AF_INET) {
355		rt = container_of(dst, struct rtable, dst);
356		return rt->rt_uses_gateway;
357	}
358
359	rt6 = container_of(dst, struct rt6_info, dst);
360	return rt6->rt6i_flags & RTF_GATEWAY;
361}
362
363static int fetch_ha(const struct dst_entry *dst, struct rdma_dev_addr *dev_addr,
364		    const struct sockaddr *dst_in, u32 seq)
365{
366	const struct sockaddr_in *dst_in4 =
367		(const struct sockaddr_in *)dst_in;
368	const struct sockaddr_in6 *dst_in6 =
369		(const struct sockaddr_in6 *)dst_in;
370	const void *daddr = (dst_in->sa_family == AF_INET) ?
371		(const void *)&dst_in4->sin_addr.s_addr :
372		(const void *)&dst_in6->sin6_addr;
373	sa_family_t family = dst_in->sa_family;
374
375	might_sleep();
376
377	/* If we have a gateway in IB mode then it must be an IB network */
378	if (has_gateway(dst, family) && dev_addr->network == RDMA_NETWORK_IB)
379		return ib_nl_fetch_ha(dev_addr, daddr, seq, family);
380	else
381		return dst_fetch_ha(dst, dev_addr, daddr);
382}
383
384static int addr4_resolve(struct sockaddr *src_sock,
385			 const struct sockaddr *dst_sock,
386			 struct rdma_dev_addr *addr,
387			 struct rtable **prt)
388{
389	struct sockaddr_in *src_in = (struct sockaddr_in *)src_sock;
390	const struct sockaddr_in *dst_in =
391			(const struct sockaddr_in *)dst_sock;
392
393	__be32 src_ip = src_in->sin_addr.s_addr;
394	__be32 dst_ip = dst_in->sin_addr.s_addr;
395	struct rtable *rt;
396	struct flowi4 fl4;
397	int ret;
398
399	memset(&fl4, 0, sizeof(fl4));
400	fl4.daddr = dst_ip;
401	fl4.saddr = src_ip;
402	fl4.flowi4_oif = addr->bound_dev_if;
403	rt = ip_route_output_key(addr->net, &fl4);
404	ret = PTR_ERR_OR_ZERO(rt);
405	if (ret)
406		return ret;
407
408	src_in->sin_addr.s_addr = fl4.saddr;
409
410	addr->hoplimit = ip4_dst_hoplimit(&rt->dst);
411
412	*prt = rt;
413	return 0;
414}
415
416#if IS_ENABLED(CONFIG_IPV6)
417static int addr6_resolve(struct sockaddr *src_sock,
418			 const struct sockaddr *dst_sock,
419			 struct rdma_dev_addr *addr,
420			 struct dst_entry **pdst)
421{
422	struct sockaddr_in6 *src_in = (struct sockaddr_in6 *)src_sock;
423	const struct sockaddr_in6 *dst_in =
424				(const struct sockaddr_in6 *)dst_sock;
425	struct flowi6 fl6;
426	struct dst_entry *dst;
427
428	memset(&fl6, 0, sizeof fl6);
429	fl6.daddr = dst_in->sin6_addr;
430	fl6.saddr = src_in->sin6_addr;
431	fl6.flowi6_oif = addr->bound_dev_if;
432
433	dst = ipv6_stub->ipv6_dst_lookup_flow(addr->net, NULL, &fl6, NULL);
434	if (IS_ERR(dst))
435		return PTR_ERR(dst);
436
437	if (ipv6_addr_any(&src_in->sin6_addr))
438		src_in->sin6_addr = fl6.saddr;
439
440	addr->hoplimit = ip6_dst_hoplimit(dst);
441
442	*pdst = dst;
443	return 0;
444}
445#else
446static int addr6_resolve(struct sockaddr *src_sock,
447			 const struct sockaddr *dst_sock,
448			 struct rdma_dev_addr *addr,
449			 struct dst_entry **pdst)
450{
451	return -EADDRNOTAVAIL;
452}
453#endif
454
455static int addr_resolve_neigh(const struct dst_entry *dst,
456			      const struct sockaddr *dst_in,
457			      struct rdma_dev_addr *addr,
458			      unsigned int ndev_flags,
459			      u32 seq)
460{
461	int ret = 0;
462
463	if (ndev_flags & IFF_LOOPBACK) {
464		memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
465	} else {
466		if (!(ndev_flags & IFF_NOARP)) {
467			/* If the device doesn't do ARP internally */
468			ret = fetch_ha(dst, addr, dst_in, seq);
469		}
470	}
471	return ret;
472}
473
474static int copy_src_l2_addr(struct rdma_dev_addr *dev_addr,
475			    const struct sockaddr *dst_in,
476			    const struct dst_entry *dst,
477			    const struct net_device *ndev)
478{
479	int ret = 0;
480
481	if (dst->dev->flags & IFF_LOOPBACK)
482		ret = rdma_translate_ip(dst_in, dev_addr);
483	else
484		rdma_copy_src_l2_addr(dev_addr, dst->dev);
485
486	/*
487	 * If there's a gateway and type of device not ARPHRD_INFINIBAND,
488	 * we're definitely in RoCE v2 (as RoCE v1 isn't routable) set the
489	 * network type accordingly.
490	 */
491	if (has_gateway(dst, dst_in->sa_family) &&
492	    ndev->type != ARPHRD_INFINIBAND)
493		dev_addr->network = dst_in->sa_family == AF_INET ?
494						RDMA_NETWORK_IPV4 :
495						RDMA_NETWORK_IPV6;
496	else
497		dev_addr->network = RDMA_NETWORK_IB;
498
499	return ret;
500}
501
502static int rdma_set_src_addr_rcu(struct rdma_dev_addr *dev_addr,
503				 unsigned int *ndev_flags,
504				 const struct sockaddr *dst_in,
505				 const struct dst_entry *dst)
506{
507	struct net_device *ndev = READ_ONCE(dst->dev);
508
509	*ndev_flags = ndev->flags;
510	/* A physical device must be the RDMA device to use */
511	if (ndev->flags & IFF_LOOPBACK) {
512		/*
513		 * RDMA (IB/RoCE, iWarp) doesn't run on lo interface or
514		 * loopback IP address. So if route is resolved to loopback
515		 * interface, translate that to a real ndev based on non
516		 * loopback IP address.
517		 */
518		ndev = rdma_find_ndev_for_src_ip_rcu(dev_net(ndev), dst_in);
519		if (IS_ERR(ndev))
520			return -ENODEV;
521	}
522
523	return copy_src_l2_addr(dev_addr, dst_in, dst, ndev);
524}
525
526static int set_addr_netns_by_gid_rcu(struct rdma_dev_addr *addr)
527{
528	struct net_device *ndev;
529
530	ndev = rdma_read_gid_attr_ndev_rcu(addr->sgid_attr);
531	if (IS_ERR(ndev))
532		return PTR_ERR(ndev);
533
534	/*
535	 * Since we are holding the rcu, reading net and ifindex
536	 * are safe without any additional reference; because
537	 * change_net_namespace() in net/core/dev.c does rcu sync
538	 * after it changes the state to IFF_DOWN and before
539	 * updating netdev fields {net, ifindex}.
540	 */
541	addr->net = dev_net(ndev);
542	addr->bound_dev_if = ndev->ifindex;
543	return 0;
544}
545
546static void rdma_addr_set_net_defaults(struct rdma_dev_addr *addr)
547{
548	addr->net = &init_net;
549	addr->bound_dev_if = 0;
550}
551
552static int addr_resolve(struct sockaddr *src_in,
553			const struct sockaddr *dst_in,
554			struct rdma_dev_addr *addr,
555			bool resolve_neigh,
556			bool resolve_by_gid_attr,
557			u32 seq)
558{
559	struct dst_entry *dst = NULL;
560	unsigned int ndev_flags = 0;
561	struct rtable *rt = NULL;
562	int ret;
563
564	if (!addr->net) {
565		pr_warn_ratelimited("%s: missing namespace\n", __func__);
566		return -EINVAL;
567	}
568
569	rcu_read_lock();
570	if (resolve_by_gid_attr) {
571		if (!addr->sgid_attr) {
572			rcu_read_unlock();
573			pr_warn_ratelimited("%s: missing gid_attr\n", __func__);
574			return -EINVAL;
575		}
576		/*
577		 * If the request is for a specific gid attribute of the
578		 * rdma_dev_addr, derive net from the netdevice of the
579		 * GID attribute.
580		 */
581		ret = set_addr_netns_by_gid_rcu(addr);
582		if (ret) {
583			rcu_read_unlock();
584			return ret;
585		}
586	}
587	if (src_in->sa_family == AF_INET) {
588		ret = addr4_resolve(src_in, dst_in, addr, &rt);
589		dst = &rt->dst;
590	} else {
591		ret = addr6_resolve(src_in, dst_in, addr, &dst);
592	}
593	if (ret) {
594		rcu_read_unlock();
595		goto done;
596	}
597	ret = rdma_set_src_addr_rcu(addr, &ndev_flags, dst_in, dst);
598	rcu_read_unlock();
599
600	/*
601	 * Resolve neighbor destination address if requested and
602	 * only if src addr translation didn't fail.
603	 */
604	if (!ret && resolve_neigh)
605		ret = addr_resolve_neigh(dst, dst_in, addr, ndev_flags, seq);
606
607	if (src_in->sa_family == AF_INET)
608		ip_rt_put(rt);
609	else
610		dst_release(dst);
611done:
612	/*
613	 * Clear the addr net to go back to its original state, only if it was
614	 * derived from GID attribute in this context.
615	 */
616	if (resolve_by_gid_attr)
617		rdma_addr_set_net_defaults(addr);
618	return ret;
619}
620
621static void process_one_req(struct work_struct *_work)
622{
623	struct addr_req *req;
624	struct sockaddr *src_in, *dst_in;
625
626	req = container_of(_work, struct addr_req, work.work);
627
628	if (req->status == -ENODATA) {
629		src_in = (struct sockaddr *)&req->src_addr;
630		dst_in = (struct sockaddr *)&req->dst_addr;
631		req->status = addr_resolve(src_in, dst_in, req->addr,
632					   true, req->resolve_by_gid_attr,
633					   req->seq);
634		if (req->status && time_after_eq(jiffies, req->timeout)) {
635			req->status = -ETIMEDOUT;
636		} else if (req->status == -ENODATA) {
637			/* requeue the work for retrying again */
638			spin_lock_bh(&lock);
639			if (!list_empty(&req->list))
640				set_timeout(req, req->timeout);
641			spin_unlock_bh(&lock);
642			return;
643		}
644	}
645
646	req->callback(req->status, (struct sockaddr *)&req->src_addr,
647		req->addr, req->context);
648	req->callback = NULL;
649
650	spin_lock_bh(&lock);
651	/*
652	 * Although the work will normally have been canceled by the workqueue,
653	 * it can still be requeued as long as it is on the req_list.
654	 */
655	cancel_delayed_work(&req->work);
656	if (!list_empty(&req->list)) {
657		list_del_init(&req->list);
658		kfree(req);
659	}
660	spin_unlock_bh(&lock);
661}
662
663int rdma_resolve_ip(struct sockaddr *src_addr, const struct sockaddr *dst_addr,
664		    struct rdma_dev_addr *addr, unsigned long timeout_ms,
665		    void (*callback)(int status, struct sockaddr *src_addr,
666				     struct rdma_dev_addr *addr, void *context),
667		    bool resolve_by_gid_attr, void *context)
668{
669	struct sockaddr *src_in, *dst_in;
670	struct addr_req *req;
671	int ret = 0;
672
673	req = kzalloc(sizeof *req, GFP_KERNEL);
674	if (!req)
675		return -ENOMEM;
676
677	src_in = (struct sockaddr *) &req->src_addr;
678	dst_in = (struct sockaddr *) &req->dst_addr;
679
680	if (src_addr) {
681		if (src_addr->sa_family != dst_addr->sa_family) {
682			ret = -EINVAL;
683			goto err;
684		}
685
686		memcpy(src_in, src_addr, rdma_addr_size(src_addr));
687	} else {
688		src_in->sa_family = dst_addr->sa_family;
689	}
690
691	memcpy(dst_in, dst_addr, rdma_addr_size(dst_addr));
692	req->addr = addr;
693	req->callback = callback;
694	req->context = context;
695	req->resolve_by_gid_attr = resolve_by_gid_attr;
696	INIT_DELAYED_WORK(&req->work, process_one_req);
697	req->seq = (u32)atomic_inc_return(&ib_nl_addr_request_seq);
698
699	req->status = addr_resolve(src_in, dst_in, addr, true,
700				   req->resolve_by_gid_attr, req->seq);
701	switch (req->status) {
702	case 0:
703		req->timeout = jiffies;
704		queue_req(req);
705		break;
706	case -ENODATA:
707		req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
708		queue_req(req);
709		break;
710	default:
711		ret = req->status;
712		goto err;
713	}
714	return ret;
715err:
716	kfree(req);
717	return ret;
718}
719EXPORT_SYMBOL(rdma_resolve_ip);
720
721int roce_resolve_route_from_path(struct sa_path_rec *rec,
722				 const struct ib_gid_attr *attr)
723{
724	union {
725		struct sockaddr     _sockaddr;
726		struct sockaddr_in  _sockaddr_in;
727		struct sockaddr_in6 _sockaddr_in6;
728	} sgid, dgid;
729	struct rdma_dev_addr dev_addr = {};
730	int ret;
731
732	might_sleep();
733
734	if (rec->roce.route_resolved)
735		return 0;
736
737	rdma_gid2ip((struct sockaddr *)&sgid, &rec->sgid);
738	rdma_gid2ip((struct sockaddr *)&dgid, &rec->dgid);
739
740	if (sgid._sockaddr.sa_family != dgid._sockaddr.sa_family)
741		return -EINVAL;
742
743	if (!attr || !attr->ndev)
744		return -EINVAL;
745
746	dev_addr.net = &init_net;
747	dev_addr.sgid_attr = attr;
748
749	ret = addr_resolve((struct sockaddr *)&sgid, (struct sockaddr *)&dgid,
750			   &dev_addr, false, true, 0);
751	if (ret)
752		return ret;
753
754	if ((dev_addr.network == RDMA_NETWORK_IPV4 ||
755	     dev_addr.network == RDMA_NETWORK_IPV6) &&
756	    rec->rec_type != SA_PATH_REC_TYPE_ROCE_V2)
757		return -EINVAL;
758
759	rec->roce.route_resolved = true;
760	return 0;
761}
762
763/**
764 * rdma_addr_cancel - Cancel resolve ip request
765 * @addr:	Pointer to address structure given previously
766 *		during rdma_resolve_ip().
767 * rdma_addr_cancel() is synchronous function which cancels any pending
768 * request if there is any.
769 */
770void rdma_addr_cancel(struct rdma_dev_addr *addr)
771{
772	struct addr_req *req, *temp_req;
773	struct addr_req *found = NULL;
774
775	spin_lock_bh(&lock);
776	list_for_each_entry_safe(req, temp_req, &req_list, list) {
777		if (req->addr == addr) {
778			/*
779			 * Removing from the list means we take ownership of
780			 * the req
781			 */
782			list_del_init(&req->list);
783			found = req;
784			break;
785		}
786	}
787	spin_unlock_bh(&lock);
788
789	if (!found)
790		return;
791
792	/*
793	 * sync canceling the work after removing it from the req_list
794	 * guarentees no work is running and none will be started.
795	 */
796	cancel_delayed_work_sync(&found->work);
797	kfree(found);
798}
799EXPORT_SYMBOL(rdma_addr_cancel);
800
801struct resolve_cb_context {
802	struct completion comp;
803	int status;
804};
805
806static void resolve_cb(int status, struct sockaddr *src_addr,
807	     struct rdma_dev_addr *addr, void *context)
808{
809	((struct resolve_cb_context *)context)->status = status;
810	complete(&((struct resolve_cb_context *)context)->comp);
811}
812
813int rdma_addr_find_l2_eth_by_grh(const union ib_gid *sgid,
814				 const union ib_gid *dgid,
815				 u8 *dmac, const struct ib_gid_attr *sgid_attr,
816				 int *hoplimit)
817{
818	struct rdma_dev_addr dev_addr;
819	struct resolve_cb_context ctx;
820	union {
821		struct sockaddr_in  _sockaddr_in;
822		struct sockaddr_in6 _sockaddr_in6;
823	} sgid_addr, dgid_addr;
824	int ret;
825
826	rdma_gid2ip((struct sockaddr *)&sgid_addr, sgid);
827	rdma_gid2ip((struct sockaddr *)&dgid_addr, dgid);
828
829	memset(&dev_addr, 0, sizeof(dev_addr));
830	dev_addr.net = &init_net;
831	dev_addr.sgid_attr = sgid_attr;
832
833	init_completion(&ctx.comp);
834	ret = rdma_resolve_ip((struct sockaddr *)&sgid_addr,
835			      (struct sockaddr *)&dgid_addr, &dev_addr, 1000,
836			      resolve_cb, true, &ctx);
837	if (ret)
838		return ret;
839
840	wait_for_completion(&ctx.comp);
841
842	ret = ctx.status;
843	if (ret)
844		return ret;
845
846	memcpy(dmac, dev_addr.dst_dev_addr, ETH_ALEN);
847	*hoplimit = dev_addr.hoplimit;
848	return 0;
849}
850
851static int netevent_callback(struct notifier_block *self, unsigned long event,
852	void *ctx)
853{
854	struct addr_req *req;
855
856	if (event == NETEVENT_NEIGH_UPDATE) {
857		struct neighbour *neigh = ctx;
858
859		if (neigh->nud_state & NUD_VALID) {
860			spin_lock_bh(&lock);
861			list_for_each_entry(req, &req_list, list)
862				set_timeout(req, jiffies);
863			spin_unlock_bh(&lock);
864		}
865	}
866	return 0;
867}
868
869static struct notifier_block nb = {
870	.notifier_call = netevent_callback
871};
872
873int addr_init(void)
874{
875	addr_wq = alloc_ordered_workqueue("ib_addr", 0);
876	if (!addr_wq)
877		return -ENOMEM;
878
879	register_netevent_notifier(&nb);
880
881	return 0;
882}
883
884void addr_cleanup(void)
885{
886	unregister_netevent_notifier(&nb);
887	destroy_workqueue(addr_wq);
888	WARN_ON(!list_empty(&req_list));
889}