xref: /linux/net/openvswitch/datapath.c (revision 9ffc93f203c18a70623f21950f1dd473c9ec48cd)
1 /*
2  * Copyright (c) 2007-2012 Nicira Networks.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of version 2 of the GNU General Public
6  * License as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software
15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
16  * 02110-1301, USA
17  */
18 
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20 
21 #include <linux/init.h>
22 #include <linux/module.h>
23 #include <linux/if_arp.h>
24 #include <linux/if_vlan.h>
25 #include <linux/in.h>
26 #include <linux/ip.h>
27 #include <linux/jhash.h>
28 #include <linux/delay.h>
29 #include <linux/time.h>
30 #include <linux/etherdevice.h>
31 #include <linux/genetlink.h>
32 #include <linux/kernel.h>
33 #include <linux/kthread.h>
34 #include <linux/mutex.h>
35 #include <linux/percpu.h>
36 #include <linux/rcupdate.h>
37 #include <linux/tcp.h>
38 #include <linux/udp.h>
39 #include <linux/ethtool.h>
40 #include <linux/wait.h>
41 #include <asm/div64.h>
42 #include <linux/highmem.h>
43 #include <linux/netfilter_bridge.h>
44 #include <linux/netfilter_ipv4.h>
45 #include <linux/inetdevice.h>
46 #include <linux/list.h>
47 #include <linux/openvswitch.h>
48 #include <linux/rculist.h>
49 #include <linux/dmi.h>
50 #include <linux/workqueue.h>
51 #include <net/genetlink.h>
52 
53 #include "datapath.h"
54 #include "flow.h"
55 #include "vport-internal_dev.h"
56 
57 /**
58  * DOC: Locking:
59  *
60  * Writes to device state (add/remove datapath, port, set operations on vports,
61  * etc.) are protected by RTNL.
62  *
63  * Writes to other state (flow table modifications, set miscellaneous datapath
64  * parameters, etc.) are protected by genl_mutex.  The RTNL lock nests inside
65  * genl_mutex.
66  *
67  * Reads are protected by RCU.
68  *
69  * There are a few special cases (mostly stats) that have their own
70  * synchronization but they nest under all of above and don't interact with
71  * each other.
72  */
73 
74 /* Global list of datapaths to enable dumping them all out.
75  * Protected by genl_mutex.
76  */
77 static LIST_HEAD(dps);
78 
79 #define REHASH_FLOW_INTERVAL (10 * 60 * HZ)
80 static void rehash_flow_table(struct work_struct *work);
81 static DECLARE_DELAYED_WORK(rehash_flow_wq, rehash_flow_table);
82 
83 static struct vport *new_vport(const struct vport_parms *);
84 static int queue_gso_packets(int dp_ifindex, struct sk_buff *,
85 			     const struct dp_upcall_info *);
86 static int queue_userspace_packet(int dp_ifindex, struct sk_buff *,
87 				  const struct dp_upcall_info *);
88 
89 /* Must be called with rcu_read_lock, genl_mutex, or RTNL lock. */
90 static struct datapath *get_dp(int dp_ifindex)
91 {
92 	struct datapath *dp = NULL;
93 	struct net_device *dev;
94 
95 	rcu_read_lock();
96 	dev = dev_get_by_index_rcu(&init_net, dp_ifindex);
97 	if (dev) {
98 		struct vport *vport = ovs_internal_dev_get_vport(dev);
99 		if (vport)
100 			dp = vport->dp;
101 	}
102 	rcu_read_unlock();
103 
104 	return dp;
105 }
106 
107 /* Must be called with rcu_read_lock or RTNL lock. */
108 const char *ovs_dp_name(const struct datapath *dp)
109 {
110 	struct vport *vport = rcu_dereference_rtnl(dp->ports[OVSP_LOCAL]);
111 	return vport->ops->get_name(vport);
112 }
113 
114 static int get_dpifindex(struct datapath *dp)
115 {
116 	struct vport *local;
117 	int ifindex;
118 
119 	rcu_read_lock();
120 
121 	local = rcu_dereference(dp->ports[OVSP_LOCAL]);
122 	if (local)
123 		ifindex = local->ops->get_ifindex(local);
124 	else
125 		ifindex = 0;
126 
127 	rcu_read_unlock();
128 
129 	return ifindex;
130 }
131 
132 static void destroy_dp_rcu(struct rcu_head *rcu)
133 {
134 	struct datapath *dp = container_of(rcu, struct datapath, rcu);
135 
136 	ovs_flow_tbl_destroy((__force struct flow_table *)dp->table);
137 	free_percpu(dp->stats_percpu);
138 	kfree(dp);
139 }
140 
141 /* Called with RTNL lock and genl_lock. */
142 static struct vport *new_vport(const struct vport_parms *parms)
143 {
144 	struct vport *vport;
145 
146 	vport = ovs_vport_add(parms);
147 	if (!IS_ERR(vport)) {
148 		struct datapath *dp = parms->dp;
149 
150 		rcu_assign_pointer(dp->ports[parms->port_no], vport);
151 		list_add(&vport->node, &dp->port_list);
152 	}
153 
154 	return vport;
155 }
156 
157 /* Called with RTNL lock. */
158 void ovs_dp_detach_port(struct vport *p)
159 {
160 	ASSERT_RTNL();
161 
162 	/* First drop references to device. */
163 	list_del(&p->node);
164 	rcu_assign_pointer(p->dp->ports[p->port_no], NULL);
165 
166 	/* Then destroy it. */
167 	ovs_vport_del(p);
168 }
169 
170 /* Must be called with rcu_read_lock. */
171 void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
172 {
173 	struct datapath *dp = p->dp;
174 	struct sw_flow *flow;
175 	struct dp_stats_percpu *stats;
176 	struct sw_flow_key key;
177 	u64 *stats_counter;
178 	int error;
179 	int key_len;
180 
181 	stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id());
182 
183 	/* Extract flow from 'skb' into 'key'. */
184 	error = ovs_flow_extract(skb, p->port_no, &key, &key_len);
185 	if (unlikely(error)) {
186 		kfree_skb(skb);
187 		return;
188 	}
189 
190 	/* Look up flow. */
191 	flow = ovs_flow_tbl_lookup(rcu_dereference(dp->table), &key, key_len);
192 	if (unlikely(!flow)) {
193 		struct dp_upcall_info upcall;
194 
195 		upcall.cmd = OVS_PACKET_CMD_MISS;
196 		upcall.key = &key;
197 		upcall.userdata = NULL;
198 		upcall.pid = p->upcall_pid;
199 		ovs_dp_upcall(dp, skb, &upcall);
200 		consume_skb(skb);
201 		stats_counter = &stats->n_missed;
202 		goto out;
203 	}
204 
205 	OVS_CB(skb)->flow = flow;
206 
207 	stats_counter = &stats->n_hit;
208 	ovs_flow_used(OVS_CB(skb)->flow, skb);
209 	ovs_execute_actions(dp, skb);
210 
211 out:
212 	/* Update datapath statistics. */
213 	u64_stats_update_begin(&stats->sync);
214 	(*stats_counter)++;
215 	u64_stats_update_end(&stats->sync);
216 }
217 
218 static struct genl_family dp_packet_genl_family = {
219 	.id = GENL_ID_GENERATE,
220 	.hdrsize = sizeof(struct ovs_header),
221 	.name = OVS_PACKET_FAMILY,
222 	.version = OVS_PACKET_VERSION,
223 	.maxattr = OVS_PACKET_ATTR_MAX
224 };
225 
226 int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
227 	      const struct dp_upcall_info *upcall_info)
228 {
229 	struct dp_stats_percpu *stats;
230 	int dp_ifindex;
231 	int err;
232 
233 	if (upcall_info->pid == 0) {
234 		err = -ENOTCONN;
235 		goto err;
236 	}
237 
238 	dp_ifindex = get_dpifindex(dp);
239 	if (!dp_ifindex) {
240 		err = -ENODEV;
241 		goto err;
242 	}
243 
244 	if (!skb_is_gso(skb))
245 		err = queue_userspace_packet(dp_ifindex, skb, upcall_info);
246 	else
247 		err = queue_gso_packets(dp_ifindex, skb, upcall_info);
248 	if (err)
249 		goto err;
250 
251 	return 0;
252 
253 err:
254 	stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id());
255 
256 	u64_stats_update_begin(&stats->sync);
257 	stats->n_lost++;
258 	u64_stats_update_end(&stats->sync);
259 
260 	return err;
261 }
262 
263 static int queue_gso_packets(int dp_ifindex, struct sk_buff *skb,
264 			     const struct dp_upcall_info *upcall_info)
265 {
266 	struct dp_upcall_info later_info;
267 	struct sw_flow_key later_key;
268 	struct sk_buff *segs, *nskb;
269 	int err;
270 
271 	segs = skb_gso_segment(skb, NETIF_F_SG | NETIF_F_HW_CSUM);
272 	if (IS_ERR(skb))
273 		return PTR_ERR(skb);
274 
275 	/* Queue all of the segments. */
276 	skb = segs;
277 	do {
278 		err = queue_userspace_packet(dp_ifindex, skb, upcall_info);
279 		if (err)
280 			break;
281 
282 		if (skb == segs && skb_shinfo(skb)->gso_type & SKB_GSO_UDP) {
283 			/* The initial flow key extracted by ovs_flow_extract()
284 			 * in this case is for a first fragment, so we need to
285 			 * properly mark later fragments.
286 			 */
287 			later_key = *upcall_info->key;
288 			later_key.ip.frag = OVS_FRAG_TYPE_LATER;
289 
290 			later_info = *upcall_info;
291 			later_info.key = &later_key;
292 			upcall_info = &later_info;
293 		}
294 	} while ((skb = skb->next));
295 
296 	/* Free all of the segments. */
297 	skb = segs;
298 	do {
299 		nskb = skb->next;
300 		if (err)
301 			kfree_skb(skb);
302 		else
303 			consume_skb(skb);
304 	} while ((skb = nskb));
305 	return err;
306 }
307 
308 static int queue_userspace_packet(int dp_ifindex, struct sk_buff *skb,
309 				  const struct dp_upcall_info *upcall_info)
310 {
311 	struct ovs_header *upcall;
312 	struct sk_buff *nskb = NULL;
313 	struct sk_buff *user_skb; /* to be queued to userspace */
314 	struct nlattr *nla;
315 	unsigned int len;
316 	int err;
317 
318 	if (vlan_tx_tag_present(skb)) {
319 		nskb = skb_clone(skb, GFP_ATOMIC);
320 		if (!nskb)
321 			return -ENOMEM;
322 
323 		nskb = __vlan_put_tag(nskb, vlan_tx_tag_get(nskb));
324 		if (!skb)
325 			return -ENOMEM;
326 
327 		nskb->vlan_tci = 0;
328 		skb = nskb;
329 	}
330 
331 	if (nla_attr_size(skb->len) > USHRT_MAX) {
332 		err = -EFBIG;
333 		goto out;
334 	}
335 
336 	len = sizeof(struct ovs_header);
337 	len += nla_total_size(skb->len);
338 	len += nla_total_size(FLOW_BUFSIZE);
339 	if (upcall_info->cmd == OVS_PACKET_CMD_ACTION)
340 		len += nla_total_size(8);
341 
342 	user_skb = genlmsg_new(len, GFP_ATOMIC);
343 	if (!user_skb) {
344 		err = -ENOMEM;
345 		goto out;
346 	}
347 
348 	upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
349 			     0, upcall_info->cmd);
350 	upcall->dp_ifindex = dp_ifindex;
351 
352 	nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_KEY);
353 	ovs_flow_to_nlattrs(upcall_info->key, user_skb);
354 	nla_nest_end(user_skb, nla);
355 
356 	if (upcall_info->userdata)
357 		nla_put_u64(user_skb, OVS_PACKET_ATTR_USERDATA,
358 			    nla_get_u64(upcall_info->userdata));
359 
360 	nla = __nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, skb->len);
361 
362 	skb_copy_and_csum_dev(skb, nla_data(nla));
363 
364 	err = genlmsg_unicast(&init_net, user_skb, upcall_info->pid);
365 
366 out:
367 	kfree_skb(nskb);
368 	return err;
369 }
370 
371 /* Called with genl_mutex. */
372 static int flush_flows(int dp_ifindex)
373 {
374 	struct flow_table *old_table;
375 	struct flow_table *new_table;
376 	struct datapath *dp;
377 
378 	dp = get_dp(dp_ifindex);
379 	if (!dp)
380 		return -ENODEV;
381 
382 	old_table = genl_dereference(dp->table);
383 	new_table = ovs_flow_tbl_alloc(TBL_MIN_BUCKETS);
384 	if (!new_table)
385 		return -ENOMEM;
386 
387 	rcu_assign_pointer(dp->table, new_table);
388 
389 	ovs_flow_tbl_deferred_destroy(old_table);
390 	return 0;
391 }
392 
393 static int validate_actions(const struct nlattr *attr,
394 				const struct sw_flow_key *key, int depth);
395 
396 static int validate_sample(const struct nlattr *attr,
397 				const struct sw_flow_key *key, int depth)
398 {
399 	const struct nlattr *attrs[OVS_SAMPLE_ATTR_MAX + 1];
400 	const struct nlattr *probability, *actions;
401 	const struct nlattr *a;
402 	int rem;
403 
404 	memset(attrs, 0, sizeof(attrs));
405 	nla_for_each_nested(a, attr, rem) {
406 		int type = nla_type(a);
407 		if (!type || type > OVS_SAMPLE_ATTR_MAX || attrs[type])
408 			return -EINVAL;
409 		attrs[type] = a;
410 	}
411 	if (rem)
412 		return -EINVAL;
413 
414 	probability = attrs[OVS_SAMPLE_ATTR_PROBABILITY];
415 	if (!probability || nla_len(probability) != sizeof(u32))
416 		return -EINVAL;
417 
418 	actions = attrs[OVS_SAMPLE_ATTR_ACTIONS];
419 	if (!actions || (nla_len(actions) && nla_len(actions) < NLA_HDRLEN))
420 		return -EINVAL;
421 	return validate_actions(actions, key, depth + 1);
422 }
423 
424 static int validate_set(const struct nlattr *a,
425 			const struct sw_flow_key *flow_key)
426 {
427 	const struct nlattr *ovs_key = nla_data(a);
428 	int key_type = nla_type(ovs_key);
429 
430 	/* There can be only one key in a action */
431 	if (nla_total_size(nla_len(ovs_key)) != nla_len(a))
432 		return -EINVAL;
433 
434 	if (key_type > OVS_KEY_ATTR_MAX ||
435 	    nla_len(ovs_key) != ovs_key_lens[key_type])
436 		return -EINVAL;
437 
438 	switch (key_type) {
439 	const struct ovs_key_ipv4 *ipv4_key;
440 
441 	case OVS_KEY_ATTR_PRIORITY:
442 	case OVS_KEY_ATTR_ETHERNET:
443 		break;
444 
445 	case OVS_KEY_ATTR_IPV4:
446 		if (flow_key->eth.type != htons(ETH_P_IP))
447 			return -EINVAL;
448 
449 		if (!flow_key->ipv4.addr.src || !flow_key->ipv4.addr.dst)
450 			return -EINVAL;
451 
452 		ipv4_key = nla_data(ovs_key);
453 		if (ipv4_key->ipv4_proto != flow_key->ip.proto)
454 			return -EINVAL;
455 
456 		if (ipv4_key->ipv4_frag != flow_key->ip.frag)
457 			return -EINVAL;
458 
459 		break;
460 
461 	case OVS_KEY_ATTR_TCP:
462 		if (flow_key->ip.proto != IPPROTO_TCP)
463 			return -EINVAL;
464 
465 		if (!flow_key->ipv4.tp.src || !flow_key->ipv4.tp.dst)
466 			return -EINVAL;
467 
468 		break;
469 
470 	case OVS_KEY_ATTR_UDP:
471 		if (flow_key->ip.proto != IPPROTO_UDP)
472 			return -EINVAL;
473 
474 		if (!flow_key->ipv4.tp.src || !flow_key->ipv4.tp.dst)
475 			return -EINVAL;
476 		break;
477 
478 	default:
479 		return -EINVAL;
480 	}
481 
482 	return 0;
483 }
484 
485 static int validate_userspace(const struct nlattr *attr)
486 {
487 	static const struct nla_policy userspace_policy[OVS_USERSPACE_ATTR_MAX + 1] =	{
488 		[OVS_USERSPACE_ATTR_PID] = {.type = NLA_U32 },
489 		[OVS_USERSPACE_ATTR_USERDATA] = {.type = NLA_U64 },
490 	};
491 	struct nlattr *a[OVS_USERSPACE_ATTR_MAX + 1];
492 	int error;
493 
494 	error = nla_parse_nested(a, OVS_USERSPACE_ATTR_MAX,
495 				 attr, userspace_policy);
496 	if (error)
497 		return error;
498 
499 	if (!a[OVS_USERSPACE_ATTR_PID] ||
500 	    !nla_get_u32(a[OVS_USERSPACE_ATTR_PID]))
501 		return -EINVAL;
502 
503 	return 0;
504 }
505 
506 static int validate_actions(const struct nlattr *attr,
507 				const struct sw_flow_key *key,  int depth)
508 {
509 	const struct nlattr *a;
510 	int rem, err;
511 
512 	if (depth >= SAMPLE_ACTION_DEPTH)
513 		return -EOVERFLOW;
514 
515 	nla_for_each_nested(a, attr, rem) {
516 		/* Expected argument lengths, (u32)-1 for variable length. */
517 		static const u32 action_lens[OVS_ACTION_ATTR_MAX + 1] = {
518 			[OVS_ACTION_ATTR_OUTPUT] = sizeof(u32),
519 			[OVS_ACTION_ATTR_USERSPACE] = (u32)-1,
520 			[OVS_ACTION_ATTR_PUSH_VLAN] = sizeof(struct ovs_action_push_vlan),
521 			[OVS_ACTION_ATTR_POP_VLAN] = 0,
522 			[OVS_ACTION_ATTR_SET] = (u32)-1,
523 			[OVS_ACTION_ATTR_SAMPLE] = (u32)-1
524 		};
525 		const struct ovs_action_push_vlan *vlan;
526 		int type = nla_type(a);
527 
528 		if (type > OVS_ACTION_ATTR_MAX ||
529 		    (action_lens[type] != nla_len(a) &&
530 		     action_lens[type] != (u32)-1))
531 			return -EINVAL;
532 
533 		switch (type) {
534 		case OVS_ACTION_ATTR_UNSPEC:
535 			return -EINVAL;
536 
537 		case OVS_ACTION_ATTR_USERSPACE:
538 			err = validate_userspace(a);
539 			if (err)
540 				return err;
541 			break;
542 
543 		case OVS_ACTION_ATTR_OUTPUT:
544 			if (nla_get_u32(a) >= DP_MAX_PORTS)
545 				return -EINVAL;
546 			break;
547 
548 
549 		case OVS_ACTION_ATTR_POP_VLAN:
550 			break;
551 
552 		case OVS_ACTION_ATTR_PUSH_VLAN:
553 			vlan = nla_data(a);
554 			if (vlan->vlan_tpid != htons(ETH_P_8021Q))
555 				return -EINVAL;
556 			if (!(vlan->vlan_tci & htons(VLAN_TAG_PRESENT)))
557 				return -EINVAL;
558 			break;
559 
560 		case OVS_ACTION_ATTR_SET:
561 			err = validate_set(a, key);
562 			if (err)
563 				return err;
564 			break;
565 
566 		case OVS_ACTION_ATTR_SAMPLE:
567 			err = validate_sample(a, key, depth);
568 			if (err)
569 				return err;
570 			break;
571 
572 		default:
573 			return -EINVAL;
574 		}
575 	}
576 
577 	if (rem > 0)
578 		return -EINVAL;
579 
580 	return 0;
581 }
582 
583 static void clear_stats(struct sw_flow *flow)
584 {
585 	flow->used = 0;
586 	flow->tcp_flags = 0;
587 	flow->packet_count = 0;
588 	flow->byte_count = 0;
589 }
590 
591 static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
592 {
593 	struct ovs_header *ovs_header = info->userhdr;
594 	struct nlattr **a = info->attrs;
595 	struct sw_flow_actions *acts;
596 	struct sk_buff *packet;
597 	struct sw_flow *flow;
598 	struct datapath *dp;
599 	struct ethhdr *eth;
600 	int len;
601 	int err;
602 	int key_len;
603 
604 	err = -EINVAL;
605 	if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] ||
606 	    !a[OVS_PACKET_ATTR_ACTIONS] ||
607 	    nla_len(a[OVS_PACKET_ATTR_PACKET]) < ETH_HLEN)
608 		goto err;
609 
610 	len = nla_len(a[OVS_PACKET_ATTR_PACKET]);
611 	packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL);
612 	err = -ENOMEM;
613 	if (!packet)
614 		goto err;
615 	skb_reserve(packet, NET_IP_ALIGN);
616 
617 	memcpy(__skb_put(packet, len), nla_data(a[OVS_PACKET_ATTR_PACKET]), len);
618 
619 	skb_reset_mac_header(packet);
620 	eth = eth_hdr(packet);
621 
622 	/* Normally, setting the skb 'protocol' field would be handled by a
623 	 * call to eth_type_trans(), but it assumes there's a sending
624 	 * device, which we may not have. */
625 	if (ntohs(eth->h_proto) >= 1536)
626 		packet->protocol = eth->h_proto;
627 	else
628 		packet->protocol = htons(ETH_P_802_2);
629 
630 	/* Build an sw_flow for sending this packet. */
631 	flow = ovs_flow_alloc();
632 	err = PTR_ERR(flow);
633 	if (IS_ERR(flow))
634 		goto err_kfree_skb;
635 
636 	err = ovs_flow_extract(packet, -1, &flow->key, &key_len);
637 	if (err)
638 		goto err_flow_free;
639 
640 	err = ovs_flow_metadata_from_nlattrs(&flow->key.phy.priority,
641 					     &flow->key.phy.in_port,
642 					     a[OVS_PACKET_ATTR_KEY]);
643 	if (err)
644 		goto err_flow_free;
645 
646 	err = validate_actions(a[OVS_PACKET_ATTR_ACTIONS], &flow->key, 0);
647 	if (err)
648 		goto err_flow_free;
649 
650 	flow->hash = ovs_flow_hash(&flow->key, key_len);
651 
652 	acts = ovs_flow_actions_alloc(a[OVS_PACKET_ATTR_ACTIONS]);
653 	err = PTR_ERR(acts);
654 	if (IS_ERR(acts))
655 		goto err_flow_free;
656 	rcu_assign_pointer(flow->sf_acts, acts);
657 
658 	OVS_CB(packet)->flow = flow;
659 	packet->priority = flow->key.phy.priority;
660 
661 	rcu_read_lock();
662 	dp = get_dp(ovs_header->dp_ifindex);
663 	err = -ENODEV;
664 	if (!dp)
665 		goto err_unlock;
666 
667 	local_bh_disable();
668 	err = ovs_execute_actions(dp, packet);
669 	local_bh_enable();
670 	rcu_read_unlock();
671 
672 	ovs_flow_free(flow);
673 	return err;
674 
675 err_unlock:
676 	rcu_read_unlock();
677 err_flow_free:
678 	ovs_flow_free(flow);
679 err_kfree_skb:
680 	kfree_skb(packet);
681 err:
682 	return err;
683 }
684 
685 static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = {
686 	[OVS_PACKET_ATTR_PACKET] = { .type = NLA_UNSPEC },
687 	[OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED },
688 	[OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED },
689 };
690 
691 static struct genl_ops dp_packet_genl_ops[] = {
692 	{ .cmd = OVS_PACKET_CMD_EXECUTE,
693 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
694 	  .policy = packet_policy,
695 	  .doit = ovs_packet_cmd_execute
696 	}
697 };
698 
699 static void get_dp_stats(struct datapath *dp, struct ovs_dp_stats *stats)
700 {
701 	int i;
702 	struct flow_table *table = genl_dereference(dp->table);
703 
704 	stats->n_flows = ovs_flow_tbl_count(table);
705 
706 	stats->n_hit = stats->n_missed = stats->n_lost = 0;
707 	for_each_possible_cpu(i) {
708 		const struct dp_stats_percpu *percpu_stats;
709 		struct dp_stats_percpu local_stats;
710 		unsigned int start;
711 
712 		percpu_stats = per_cpu_ptr(dp->stats_percpu, i);
713 
714 		do {
715 			start = u64_stats_fetch_begin_bh(&percpu_stats->sync);
716 			local_stats = *percpu_stats;
717 		} while (u64_stats_fetch_retry_bh(&percpu_stats->sync, start));
718 
719 		stats->n_hit += local_stats.n_hit;
720 		stats->n_missed += local_stats.n_missed;
721 		stats->n_lost += local_stats.n_lost;
722 	}
723 }
724 
725 static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = {
726 	[OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED },
727 	[OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED },
728 	[OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG },
729 };
730 
731 static struct genl_family dp_flow_genl_family = {
732 	.id = GENL_ID_GENERATE,
733 	.hdrsize = sizeof(struct ovs_header),
734 	.name = OVS_FLOW_FAMILY,
735 	.version = OVS_FLOW_VERSION,
736 	.maxattr = OVS_FLOW_ATTR_MAX
737 };
738 
739 static struct genl_multicast_group ovs_dp_flow_multicast_group = {
740 	.name = OVS_FLOW_MCGROUP
741 };
742 
743 /* Called with genl_lock. */
744 static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp,
745 				  struct sk_buff *skb, u32 pid,
746 				  u32 seq, u32 flags, u8 cmd)
747 {
748 	const int skb_orig_len = skb->len;
749 	const struct sw_flow_actions *sf_acts;
750 	struct ovs_flow_stats stats;
751 	struct ovs_header *ovs_header;
752 	struct nlattr *nla;
753 	unsigned long used;
754 	u8 tcp_flags;
755 	int err;
756 
757 	sf_acts = rcu_dereference_protected(flow->sf_acts,
758 					    lockdep_genl_is_held());
759 
760 	ovs_header = genlmsg_put(skb, pid, seq, &dp_flow_genl_family, flags, cmd);
761 	if (!ovs_header)
762 		return -EMSGSIZE;
763 
764 	ovs_header->dp_ifindex = get_dpifindex(dp);
765 
766 	nla = nla_nest_start(skb, OVS_FLOW_ATTR_KEY);
767 	if (!nla)
768 		goto nla_put_failure;
769 	err = ovs_flow_to_nlattrs(&flow->key, skb);
770 	if (err)
771 		goto error;
772 	nla_nest_end(skb, nla);
773 
774 	spin_lock_bh(&flow->lock);
775 	used = flow->used;
776 	stats.n_packets = flow->packet_count;
777 	stats.n_bytes = flow->byte_count;
778 	tcp_flags = flow->tcp_flags;
779 	spin_unlock_bh(&flow->lock);
780 
781 	if (used)
782 		NLA_PUT_U64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used));
783 
784 	if (stats.n_packets)
785 		NLA_PUT(skb, OVS_FLOW_ATTR_STATS,
786 			sizeof(struct ovs_flow_stats), &stats);
787 
788 	if (tcp_flags)
789 		NLA_PUT_U8(skb, OVS_FLOW_ATTR_TCP_FLAGS, tcp_flags);
790 
791 	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
792 	 * this is the first flow to be dumped into 'skb'.  This is unusual for
793 	 * Netlink but individual action lists can be longer than
794 	 * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this.
795 	 * The userspace caller can always fetch the actions separately if it
796 	 * really wants them.  (Most userspace callers in fact don't care.)
797 	 *
798 	 * This can only fail for dump operations because the skb is always
799 	 * properly sized for single flows.
800 	 */
801 	err = nla_put(skb, OVS_FLOW_ATTR_ACTIONS, sf_acts->actions_len,
802 		      sf_acts->actions);
803 	if (err < 0 && skb_orig_len)
804 		goto error;
805 
806 	return genlmsg_end(skb, ovs_header);
807 
808 nla_put_failure:
809 	err = -EMSGSIZE;
810 error:
811 	genlmsg_cancel(skb, ovs_header);
812 	return err;
813 }
814 
815 static struct sk_buff *ovs_flow_cmd_alloc_info(struct sw_flow *flow)
816 {
817 	const struct sw_flow_actions *sf_acts;
818 	int len;
819 
820 	sf_acts = rcu_dereference_protected(flow->sf_acts,
821 					    lockdep_genl_is_held());
822 
823 	/* OVS_FLOW_ATTR_KEY */
824 	len = nla_total_size(FLOW_BUFSIZE);
825 	/* OVS_FLOW_ATTR_ACTIONS */
826 	len += nla_total_size(sf_acts->actions_len);
827 	/* OVS_FLOW_ATTR_STATS */
828 	len += nla_total_size(sizeof(struct ovs_flow_stats));
829 	/* OVS_FLOW_ATTR_TCP_FLAGS */
830 	len += nla_total_size(1);
831 	/* OVS_FLOW_ATTR_USED */
832 	len += nla_total_size(8);
833 
834 	len += NLMSG_ALIGN(sizeof(struct ovs_header));
835 
836 	return genlmsg_new(len, GFP_KERNEL);
837 }
838 
839 static struct sk_buff *ovs_flow_cmd_build_info(struct sw_flow *flow,
840 					       struct datapath *dp,
841 					       u32 pid, u32 seq, u8 cmd)
842 {
843 	struct sk_buff *skb;
844 	int retval;
845 
846 	skb = ovs_flow_cmd_alloc_info(flow);
847 	if (!skb)
848 		return ERR_PTR(-ENOMEM);
849 
850 	retval = ovs_flow_cmd_fill_info(flow, dp, skb, pid, seq, 0, cmd);
851 	BUG_ON(retval < 0);
852 	return skb;
853 }
854 
855 static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
856 {
857 	struct nlattr **a = info->attrs;
858 	struct ovs_header *ovs_header = info->userhdr;
859 	struct sw_flow_key key;
860 	struct sw_flow *flow;
861 	struct sk_buff *reply;
862 	struct datapath *dp;
863 	struct flow_table *table;
864 	int error;
865 	int key_len;
866 
867 	/* Extract key. */
868 	error = -EINVAL;
869 	if (!a[OVS_FLOW_ATTR_KEY])
870 		goto error;
871 	error = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]);
872 	if (error)
873 		goto error;
874 
875 	/* Validate actions. */
876 	if (a[OVS_FLOW_ATTR_ACTIONS]) {
877 		error = validate_actions(a[OVS_FLOW_ATTR_ACTIONS], &key,  0);
878 		if (error)
879 			goto error;
880 	} else if (info->genlhdr->cmd == OVS_FLOW_CMD_NEW) {
881 		error = -EINVAL;
882 		goto error;
883 	}
884 
885 	dp = get_dp(ovs_header->dp_ifindex);
886 	error = -ENODEV;
887 	if (!dp)
888 		goto error;
889 
890 	table = genl_dereference(dp->table);
891 	flow = ovs_flow_tbl_lookup(table, &key, key_len);
892 	if (!flow) {
893 		struct sw_flow_actions *acts;
894 
895 		/* Bail out if we're not allowed to create a new flow. */
896 		error = -ENOENT;
897 		if (info->genlhdr->cmd == OVS_FLOW_CMD_SET)
898 			goto error;
899 
900 		/* Expand table, if necessary, to make room. */
901 		if (ovs_flow_tbl_need_to_expand(table)) {
902 			struct flow_table *new_table;
903 
904 			new_table = ovs_flow_tbl_expand(table);
905 			if (!IS_ERR(new_table)) {
906 				rcu_assign_pointer(dp->table, new_table);
907 				ovs_flow_tbl_deferred_destroy(table);
908 				table = genl_dereference(dp->table);
909 			}
910 		}
911 
912 		/* Allocate flow. */
913 		flow = ovs_flow_alloc();
914 		if (IS_ERR(flow)) {
915 			error = PTR_ERR(flow);
916 			goto error;
917 		}
918 		flow->key = key;
919 		clear_stats(flow);
920 
921 		/* Obtain actions. */
922 		acts = ovs_flow_actions_alloc(a[OVS_FLOW_ATTR_ACTIONS]);
923 		error = PTR_ERR(acts);
924 		if (IS_ERR(acts))
925 			goto error_free_flow;
926 		rcu_assign_pointer(flow->sf_acts, acts);
927 
928 		/* Put flow in bucket. */
929 		flow->hash = ovs_flow_hash(&key, key_len);
930 		ovs_flow_tbl_insert(table, flow);
931 
932 		reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid,
933 						info->snd_seq,
934 						OVS_FLOW_CMD_NEW);
935 	} else {
936 		/* We found a matching flow. */
937 		struct sw_flow_actions *old_acts;
938 		struct nlattr *acts_attrs;
939 
940 		/* Bail out if we're not allowed to modify an existing flow.
941 		 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
942 		 * because Generic Netlink treats the latter as a dump
943 		 * request.  We also accept NLM_F_EXCL in case that bug ever
944 		 * gets fixed.
945 		 */
946 		error = -EEXIST;
947 		if (info->genlhdr->cmd == OVS_FLOW_CMD_NEW &&
948 		    info->nlhdr->nlmsg_flags & (NLM_F_CREATE | NLM_F_EXCL))
949 			goto error;
950 
951 		/* Update actions. */
952 		old_acts = rcu_dereference_protected(flow->sf_acts,
953 						     lockdep_genl_is_held());
954 		acts_attrs = a[OVS_FLOW_ATTR_ACTIONS];
955 		if (acts_attrs &&
956 		   (old_acts->actions_len != nla_len(acts_attrs) ||
957 		   memcmp(old_acts->actions, nla_data(acts_attrs),
958 			  old_acts->actions_len))) {
959 			struct sw_flow_actions *new_acts;
960 
961 			new_acts = ovs_flow_actions_alloc(acts_attrs);
962 			error = PTR_ERR(new_acts);
963 			if (IS_ERR(new_acts))
964 				goto error;
965 
966 			rcu_assign_pointer(flow->sf_acts, new_acts);
967 			ovs_flow_deferred_free_acts(old_acts);
968 		}
969 
970 		reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid,
971 					       info->snd_seq, OVS_FLOW_CMD_NEW);
972 
973 		/* Clear stats. */
974 		if (a[OVS_FLOW_ATTR_CLEAR]) {
975 			spin_lock_bh(&flow->lock);
976 			clear_stats(flow);
977 			spin_unlock_bh(&flow->lock);
978 		}
979 	}
980 
981 	if (!IS_ERR(reply))
982 		genl_notify(reply, genl_info_net(info), info->snd_pid,
983 			   ovs_dp_flow_multicast_group.id, info->nlhdr,
984 			   GFP_KERNEL);
985 	else
986 		netlink_set_err(init_net.genl_sock, 0,
987 				ovs_dp_flow_multicast_group.id, PTR_ERR(reply));
988 	return 0;
989 
990 error_free_flow:
991 	ovs_flow_free(flow);
992 error:
993 	return error;
994 }
995 
996 static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
997 {
998 	struct nlattr **a = info->attrs;
999 	struct ovs_header *ovs_header = info->userhdr;
1000 	struct sw_flow_key key;
1001 	struct sk_buff *reply;
1002 	struct sw_flow *flow;
1003 	struct datapath *dp;
1004 	struct flow_table *table;
1005 	int err;
1006 	int key_len;
1007 
1008 	if (!a[OVS_FLOW_ATTR_KEY])
1009 		return -EINVAL;
1010 	err = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]);
1011 	if (err)
1012 		return err;
1013 
1014 	dp = get_dp(ovs_header->dp_ifindex);
1015 	if (!dp)
1016 		return -ENODEV;
1017 
1018 	table = genl_dereference(dp->table);
1019 	flow = ovs_flow_tbl_lookup(table, &key, key_len);
1020 	if (!flow)
1021 		return -ENOENT;
1022 
1023 	reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid,
1024 					info->snd_seq, OVS_FLOW_CMD_NEW);
1025 	if (IS_ERR(reply))
1026 		return PTR_ERR(reply);
1027 
1028 	return genlmsg_reply(reply, info);
1029 }
1030 
1031 static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
1032 {
1033 	struct nlattr **a = info->attrs;
1034 	struct ovs_header *ovs_header = info->userhdr;
1035 	struct sw_flow_key key;
1036 	struct sk_buff *reply;
1037 	struct sw_flow *flow;
1038 	struct datapath *dp;
1039 	struct flow_table *table;
1040 	int err;
1041 	int key_len;
1042 
1043 	if (!a[OVS_FLOW_ATTR_KEY])
1044 		return flush_flows(ovs_header->dp_ifindex);
1045 	err = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]);
1046 	if (err)
1047 		return err;
1048 
1049 	dp = get_dp(ovs_header->dp_ifindex);
1050 	if (!dp)
1051 		return -ENODEV;
1052 
1053 	table = genl_dereference(dp->table);
1054 	flow = ovs_flow_tbl_lookup(table, &key, key_len);
1055 	if (!flow)
1056 		return -ENOENT;
1057 
1058 	reply = ovs_flow_cmd_alloc_info(flow);
1059 	if (!reply)
1060 		return -ENOMEM;
1061 
1062 	ovs_flow_tbl_remove(table, flow);
1063 
1064 	err = ovs_flow_cmd_fill_info(flow, dp, reply, info->snd_pid,
1065 				     info->snd_seq, 0, OVS_FLOW_CMD_DEL);
1066 	BUG_ON(err < 0);
1067 
1068 	ovs_flow_deferred_free(flow);
1069 
1070 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1071 		    ovs_dp_flow_multicast_group.id, info->nlhdr, GFP_KERNEL);
1072 	return 0;
1073 }
1074 
1075 static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1076 {
1077 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1078 	struct datapath *dp;
1079 	struct flow_table *table;
1080 
1081 	dp = get_dp(ovs_header->dp_ifindex);
1082 	if (!dp)
1083 		return -ENODEV;
1084 
1085 	table = genl_dereference(dp->table);
1086 
1087 	for (;;) {
1088 		struct sw_flow *flow;
1089 		u32 bucket, obj;
1090 
1091 		bucket = cb->args[0];
1092 		obj = cb->args[1];
1093 		flow = ovs_flow_tbl_next(table, &bucket, &obj);
1094 		if (!flow)
1095 			break;
1096 
1097 		if (ovs_flow_cmd_fill_info(flow, dp, skb,
1098 					   NETLINK_CB(cb->skb).pid,
1099 					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
1100 					   OVS_FLOW_CMD_NEW) < 0)
1101 			break;
1102 
1103 		cb->args[0] = bucket;
1104 		cb->args[1] = obj;
1105 	}
1106 	return skb->len;
1107 }
1108 
1109 static struct genl_ops dp_flow_genl_ops[] = {
1110 	{ .cmd = OVS_FLOW_CMD_NEW,
1111 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1112 	  .policy = flow_policy,
1113 	  .doit = ovs_flow_cmd_new_or_set
1114 	},
1115 	{ .cmd = OVS_FLOW_CMD_DEL,
1116 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1117 	  .policy = flow_policy,
1118 	  .doit = ovs_flow_cmd_del
1119 	},
1120 	{ .cmd = OVS_FLOW_CMD_GET,
1121 	  .flags = 0,		    /* OK for unprivileged users. */
1122 	  .policy = flow_policy,
1123 	  .doit = ovs_flow_cmd_get,
1124 	  .dumpit = ovs_flow_cmd_dump
1125 	},
1126 	{ .cmd = OVS_FLOW_CMD_SET,
1127 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1128 	  .policy = flow_policy,
1129 	  .doit = ovs_flow_cmd_new_or_set,
1130 	},
1131 };
1132 
1133 static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
1134 	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1135 	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1136 };
1137 
1138 static struct genl_family dp_datapath_genl_family = {
1139 	.id = GENL_ID_GENERATE,
1140 	.hdrsize = sizeof(struct ovs_header),
1141 	.name = OVS_DATAPATH_FAMILY,
1142 	.version = OVS_DATAPATH_VERSION,
1143 	.maxattr = OVS_DP_ATTR_MAX
1144 };
1145 
1146 static struct genl_multicast_group ovs_dp_datapath_multicast_group = {
1147 	.name = OVS_DATAPATH_MCGROUP
1148 };
1149 
1150 static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
1151 				u32 pid, u32 seq, u32 flags, u8 cmd)
1152 {
1153 	struct ovs_header *ovs_header;
1154 	struct ovs_dp_stats dp_stats;
1155 	int err;
1156 
1157 	ovs_header = genlmsg_put(skb, pid, seq, &dp_datapath_genl_family,
1158 				   flags, cmd);
1159 	if (!ovs_header)
1160 		goto error;
1161 
1162 	ovs_header->dp_ifindex = get_dpifindex(dp);
1163 
1164 	rcu_read_lock();
1165 	err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp));
1166 	rcu_read_unlock();
1167 	if (err)
1168 		goto nla_put_failure;
1169 
1170 	get_dp_stats(dp, &dp_stats);
1171 	NLA_PUT(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats), &dp_stats);
1172 
1173 	return genlmsg_end(skb, ovs_header);
1174 
1175 nla_put_failure:
1176 	genlmsg_cancel(skb, ovs_header);
1177 error:
1178 	return -EMSGSIZE;
1179 }
1180 
1181 static struct sk_buff *ovs_dp_cmd_build_info(struct datapath *dp, u32 pid,
1182 					     u32 seq, u8 cmd)
1183 {
1184 	struct sk_buff *skb;
1185 	int retval;
1186 
1187 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1188 	if (!skb)
1189 		return ERR_PTR(-ENOMEM);
1190 
1191 	retval = ovs_dp_cmd_fill_info(dp, skb, pid, seq, 0, cmd);
1192 	if (retval < 0) {
1193 		kfree_skb(skb);
1194 		return ERR_PTR(retval);
1195 	}
1196 	return skb;
1197 }
1198 
1199 /* Called with genl_mutex and optionally with RTNL lock also. */
1200 static struct datapath *lookup_datapath(struct ovs_header *ovs_header,
1201 					struct nlattr *a[OVS_DP_ATTR_MAX + 1])
1202 {
1203 	struct datapath *dp;
1204 
1205 	if (!a[OVS_DP_ATTR_NAME])
1206 		dp = get_dp(ovs_header->dp_ifindex);
1207 	else {
1208 		struct vport *vport;
1209 
1210 		rcu_read_lock();
1211 		vport = ovs_vport_locate(nla_data(a[OVS_DP_ATTR_NAME]));
1212 		dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL;
1213 		rcu_read_unlock();
1214 	}
1215 	return dp ? dp : ERR_PTR(-ENODEV);
1216 }
1217 
1218 static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
1219 {
1220 	struct nlattr **a = info->attrs;
1221 	struct vport_parms parms;
1222 	struct sk_buff *reply;
1223 	struct datapath *dp;
1224 	struct vport *vport;
1225 	int err;
1226 
1227 	err = -EINVAL;
1228 	if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
1229 		goto err;
1230 
1231 	rtnl_lock();
1232 	err = -ENODEV;
1233 	if (!try_module_get(THIS_MODULE))
1234 		goto err_unlock_rtnl;
1235 
1236 	err = -ENOMEM;
1237 	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
1238 	if (dp == NULL)
1239 		goto err_put_module;
1240 	INIT_LIST_HEAD(&dp->port_list);
1241 
1242 	/* Allocate table. */
1243 	err = -ENOMEM;
1244 	rcu_assign_pointer(dp->table, ovs_flow_tbl_alloc(TBL_MIN_BUCKETS));
1245 	if (!dp->table)
1246 		goto err_free_dp;
1247 
1248 	dp->stats_percpu = alloc_percpu(struct dp_stats_percpu);
1249 	if (!dp->stats_percpu) {
1250 		err = -ENOMEM;
1251 		goto err_destroy_table;
1252 	}
1253 
1254 	/* Set up our datapath device. */
1255 	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
1256 	parms.type = OVS_VPORT_TYPE_INTERNAL;
1257 	parms.options = NULL;
1258 	parms.dp = dp;
1259 	parms.port_no = OVSP_LOCAL;
1260 	parms.upcall_pid = nla_get_u32(a[OVS_DP_ATTR_UPCALL_PID]);
1261 
1262 	vport = new_vport(&parms);
1263 	if (IS_ERR(vport)) {
1264 		err = PTR_ERR(vport);
1265 		if (err == -EBUSY)
1266 			err = -EEXIST;
1267 
1268 		goto err_destroy_percpu;
1269 	}
1270 
1271 	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
1272 				      info->snd_seq, OVS_DP_CMD_NEW);
1273 	err = PTR_ERR(reply);
1274 	if (IS_ERR(reply))
1275 		goto err_destroy_local_port;
1276 
1277 	list_add_tail(&dp->list_node, &dps);
1278 	rtnl_unlock();
1279 
1280 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1281 		    ovs_dp_datapath_multicast_group.id, info->nlhdr,
1282 		    GFP_KERNEL);
1283 	return 0;
1284 
1285 err_destroy_local_port:
1286 	ovs_dp_detach_port(rtnl_dereference(dp->ports[OVSP_LOCAL]));
1287 err_destroy_percpu:
1288 	free_percpu(dp->stats_percpu);
1289 err_destroy_table:
1290 	ovs_flow_tbl_destroy(genl_dereference(dp->table));
1291 err_free_dp:
1292 	kfree(dp);
1293 err_put_module:
1294 	module_put(THIS_MODULE);
1295 err_unlock_rtnl:
1296 	rtnl_unlock();
1297 err:
1298 	return err;
1299 }
1300 
1301 static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
1302 {
1303 	struct vport *vport, *next_vport;
1304 	struct sk_buff *reply;
1305 	struct datapath *dp;
1306 	int err;
1307 
1308 	rtnl_lock();
1309 	dp = lookup_datapath(info->userhdr, info->attrs);
1310 	err = PTR_ERR(dp);
1311 	if (IS_ERR(dp))
1312 		goto exit_unlock;
1313 
1314 	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
1315 				      info->snd_seq, OVS_DP_CMD_DEL);
1316 	err = PTR_ERR(reply);
1317 	if (IS_ERR(reply))
1318 		goto exit_unlock;
1319 
1320 	list_for_each_entry_safe(vport, next_vport, &dp->port_list, node)
1321 		if (vport->port_no != OVSP_LOCAL)
1322 			ovs_dp_detach_port(vport);
1323 
1324 	list_del(&dp->list_node);
1325 	ovs_dp_detach_port(rtnl_dereference(dp->ports[OVSP_LOCAL]));
1326 
1327 	/* rtnl_unlock() will wait until all the references to devices that
1328 	 * are pending unregistration have been dropped.  We do it here to
1329 	 * ensure that any internal devices (which contain DP pointers) are
1330 	 * fully destroyed before freeing the datapath.
1331 	 */
1332 	rtnl_unlock();
1333 
1334 	call_rcu(&dp->rcu, destroy_dp_rcu);
1335 	module_put(THIS_MODULE);
1336 
1337 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1338 		    ovs_dp_datapath_multicast_group.id, info->nlhdr,
1339 		    GFP_KERNEL);
1340 
1341 	return 0;
1342 
1343 exit_unlock:
1344 	rtnl_unlock();
1345 	return err;
1346 }
1347 
1348 static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
1349 {
1350 	struct sk_buff *reply;
1351 	struct datapath *dp;
1352 	int err;
1353 
1354 	dp = lookup_datapath(info->userhdr, info->attrs);
1355 	if (IS_ERR(dp))
1356 		return PTR_ERR(dp);
1357 
1358 	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
1359 				      info->snd_seq, OVS_DP_CMD_NEW);
1360 	if (IS_ERR(reply)) {
1361 		err = PTR_ERR(reply);
1362 		netlink_set_err(init_net.genl_sock, 0,
1363 				ovs_dp_datapath_multicast_group.id, err);
1364 		return 0;
1365 	}
1366 
1367 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1368 		    ovs_dp_datapath_multicast_group.id, info->nlhdr,
1369 		    GFP_KERNEL);
1370 
1371 	return 0;
1372 }
1373 
1374 static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
1375 {
1376 	struct sk_buff *reply;
1377 	struct datapath *dp;
1378 
1379 	dp = lookup_datapath(info->userhdr, info->attrs);
1380 	if (IS_ERR(dp))
1381 		return PTR_ERR(dp);
1382 
1383 	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
1384 				      info->snd_seq, OVS_DP_CMD_NEW);
1385 	if (IS_ERR(reply))
1386 		return PTR_ERR(reply);
1387 
1388 	return genlmsg_reply(reply, info);
1389 }
1390 
1391 static int ovs_dp_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1392 {
1393 	struct datapath *dp;
1394 	int skip = cb->args[0];
1395 	int i = 0;
1396 
1397 	list_for_each_entry(dp, &dps, list_node) {
1398 		if (i >= skip &&
1399 		    ovs_dp_cmd_fill_info(dp, skb, NETLINK_CB(cb->skb).pid,
1400 					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1401 					 OVS_DP_CMD_NEW) < 0)
1402 			break;
1403 		i++;
1404 	}
1405 
1406 	cb->args[0] = i;
1407 
1408 	return skb->len;
1409 }
1410 
1411 static struct genl_ops dp_datapath_genl_ops[] = {
1412 	{ .cmd = OVS_DP_CMD_NEW,
1413 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1414 	  .policy = datapath_policy,
1415 	  .doit = ovs_dp_cmd_new
1416 	},
1417 	{ .cmd = OVS_DP_CMD_DEL,
1418 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1419 	  .policy = datapath_policy,
1420 	  .doit = ovs_dp_cmd_del
1421 	},
1422 	{ .cmd = OVS_DP_CMD_GET,
1423 	  .flags = 0,		    /* OK for unprivileged users. */
1424 	  .policy = datapath_policy,
1425 	  .doit = ovs_dp_cmd_get,
1426 	  .dumpit = ovs_dp_cmd_dump
1427 	},
1428 	{ .cmd = OVS_DP_CMD_SET,
1429 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1430 	  .policy = datapath_policy,
1431 	  .doit = ovs_dp_cmd_set,
1432 	},
1433 };
1434 
1435 static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
1436 	[OVS_VPORT_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1437 	[OVS_VPORT_ATTR_STATS] = { .len = sizeof(struct ovs_vport_stats) },
1438 	[OVS_VPORT_ATTR_PORT_NO] = { .type = NLA_U32 },
1439 	[OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 },
1440 	[OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1441 	[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
1442 };
1443 
1444 static struct genl_family dp_vport_genl_family = {
1445 	.id = GENL_ID_GENERATE,
1446 	.hdrsize = sizeof(struct ovs_header),
1447 	.name = OVS_VPORT_FAMILY,
1448 	.version = OVS_VPORT_VERSION,
1449 	.maxattr = OVS_VPORT_ATTR_MAX
1450 };
1451 
1452 struct genl_multicast_group ovs_dp_vport_multicast_group = {
1453 	.name = OVS_VPORT_MCGROUP
1454 };
1455 
1456 /* Called with RTNL lock or RCU read lock. */
1457 static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
1458 				   u32 pid, u32 seq, u32 flags, u8 cmd)
1459 {
1460 	struct ovs_header *ovs_header;
1461 	struct ovs_vport_stats vport_stats;
1462 	int err;
1463 
1464 	ovs_header = genlmsg_put(skb, pid, seq, &dp_vport_genl_family,
1465 				 flags, cmd);
1466 	if (!ovs_header)
1467 		return -EMSGSIZE;
1468 
1469 	ovs_header->dp_ifindex = get_dpifindex(vport->dp);
1470 
1471 	NLA_PUT_U32(skb, OVS_VPORT_ATTR_PORT_NO, vport->port_no);
1472 	NLA_PUT_U32(skb, OVS_VPORT_ATTR_TYPE, vport->ops->type);
1473 	NLA_PUT_STRING(skb, OVS_VPORT_ATTR_NAME, vport->ops->get_name(vport));
1474 	NLA_PUT_U32(skb, OVS_VPORT_ATTR_UPCALL_PID, vport->upcall_pid);
1475 
1476 	ovs_vport_get_stats(vport, &vport_stats);
1477 	NLA_PUT(skb, OVS_VPORT_ATTR_STATS, sizeof(struct ovs_vport_stats),
1478 		&vport_stats);
1479 
1480 	err = ovs_vport_get_options(vport, skb);
1481 	if (err == -EMSGSIZE)
1482 		goto error;
1483 
1484 	return genlmsg_end(skb, ovs_header);
1485 
1486 nla_put_failure:
1487 	err = -EMSGSIZE;
1488 error:
1489 	genlmsg_cancel(skb, ovs_header);
1490 	return err;
1491 }
1492 
1493 /* Called with RTNL lock or RCU read lock. */
1494 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, u32 pid,
1495 					 u32 seq, u8 cmd)
1496 {
1497 	struct sk_buff *skb;
1498 	int retval;
1499 
1500 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1501 	if (!skb)
1502 		return ERR_PTR(-ENOMEM);
1503 
1504 	retval = ovs_vport_cmd_fill_info(vport, skb, pid, seq, 0, cmd);
1505 	if (retval < 0) {
1506 		kfree_skb(skb);
1507 		return ERR_PTR(retval);
1508 	}
1509 	return skb;
1510 }
1511 
1512 /* Called with RTNL lock or RCU read lock. */
1513 static struct vport *lookup_vport(struct ovs_header *ovs_header,
1514 				  struct nlattr *a[OVS_VPORT_ATTR_MAX + 1])
1515 {
1516 	struct datapath *dp;
1517 	struct vport *vport;
1518 
1519 	if (a[OVS_VPORT_ATTR_NAME]) {
1520 		vport = ovs_vport_locate(nla_data(a[OVS_VPORT_ATTR_NAME]));
1521 		if (!vport)
1522 			return ERR_PTR(-ENODEV);
1523 		if (ovs_header->dp_ifindex &&
1524 		    ovs_header->dp_ifindex != get_dpifindex(vport->dp))
1525 			return ERR_PTR(-ENODEV);
1526 		return vport;
1527 	} else if (a[OVS_VPORT_ATTR_PORT_NO]) {
1528 		u32 port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
1529 
1530 		if (port_no >= DP_MAX_PORTS)
1531 			return ERR_PTR(-EFBIG);
1532 
1533 		dp = get_dp(ovs_header->dp_ifindex);
1534 		if (!dp)
1535 			return ERR_PTR(-ENODEV);
1536 
1537 		vport = rcu_dereference_rtnl(dp->ports[port_no]);
1538 		if (!vport)
1539 			return ERR_PTR(-ENOENT);
1540 		return vport;
1541 	} else
1542 		return ERR_PTR(-EINVAL);
1543 }
1544 
1545 static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
1546 {
1547 	struct nlattr **a = info->attrs;
1548 	struct ovs_header *ovs_header = info->userhdr;
1549 	struct vport_parms parms;
1550 	struct sk_buff *reply;
1551 	struct vport *vport;
1552 	struct datapath *dp;
1553 	u32 port_no;
1554 	int err;
1555 
1556 	err = -EINVAL;
1557 	if (!a[OVS_VPORT_ATTR_NAME] || !a[OVS_VPORT_ATTR_TYPE] ||
1558 	    !a[OVS_VPORT_ATTR_UPCALL_PID])
1559 		goto exit;
1560 
1561 	rtnl_lock();
1562 	dp = get_dp(ovs_header->dp_ifindex);
1563 	err = -ENODEV;
1564 	if (!dp)
1565 		goto exit_unlock;
1566 
1567 	if (a[OVS_VPORT_ATTR_PORT_NO]) {
1568 		port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
1569 
1570 		err = -EFBIG;
1571 		if (port_no >= DP_MAX_PORTS)
1572 			goto exit_unlock;
1573 
1574 		vport = rtnl_dereference(dp->ports[port_no]);
1575 		err = -EBUSY;
1576 		if (vport)
1577 			goto exit_unlock;
1578 	} else {
1579 		for (port_no = 1; ; port_no++) {
1580 			if (port_no >= DP_MAX_PORTS) {
1581 				err = -EFBIG;
1582 				goto exit_unlock;
1583 			}
1584 			vport = rtnl_dereference(dp->ports[port_no]);
1585 			if (!vport)
1586 				break;
1587 		}
1588 	}
1589 
1590 	parms.name = nla_data(a[OVS_VPORT_ATTR_NAME]);
1591 	parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
1592 	parms.options = a[OVS_VPORT_ATTR_OPTIONS];
1593 	parms.dp = dp;
1594 	parms.port_no = port_no;
1595 	parms.upcall_pid = nla_get_u32(a[OVS_VPORT_ATTR_UPCALL_PID]);
1596 
1597 	vport = new_vport(&parms);
1598 	err = PTR_ERR(vport);
1599 	if (IS_ERR(vport))
1600 		goto exit_unlock;
1601 
1602 	reply = ovs_vport_cmd_build_info(vport, info->snd_pid, info->snd_seq,
1603 					 OVS_VPORT_CMD_NEW);
1604 	if (IS_ERR(reply)) {
1605 		err = PTR_ERR(reply);
1606 		ovs_dp_detach_port(vport);
1607 		goto exit_unlock;
1608 	}
1609 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1610 		    ovs_dp_vport_multicast_group.id, info->nlhdr, GFP_KERNEL);
1611 
1612 exit_unlock:
1613 	rtnl_unlock();
1614 exit:
1615 	return err;
1616 }
1617 
1618 static int ovs_vport_cmd_set(struct sk_buff *skb, struct genl_info *info)
1619 {
1620 	struct nlattr **a = info->attrs;
1621 	struct sk_buff *reply;
1622 	struct vport *vport;
1623 	int err;
1624 
1625 	rtnl_lock();
1626 	vport = lookup_vport(info->userhdr, a);
1627 	err = PTR_ERR(vport);
1628 	if (IS_ERR(vport))
1629 		goto exit_unlock;
1630 
1631 	err = 0;
1632 	if (a[OVS_VPORT_ATTR_TYPE] &&
1633 	    nla_get_u32(a[OVS_VPORT_ATTR_TYPE]) != vport->ops->type)
1634 		err = -EINVAL;
1635 
1636 	if (!err && a[OVS_VPORT_ATTR_OPTIONS])
1637 		err = ovs_vport_set_options(vport, a[OVS_VPORT_ATTR_OPTIONS]);
1638 	if (!err && a[OVS_VPORT_ATTR_UPCALL_PID])
1639 		vport->upcall_pid = nla_get_u32(a[OVS_VPORT_ATTR_UPCALL_PID]);
1640 
1641 	reply = ovs_vport_cmd_build_info(vport, info->snd_pid, info->snd_seq,
1642 					 OVS_VPORT_CMD_NEW);
1643 	if (IS_ERR(reply)) {
1644 		err = PTR_ERR(reply);
1645 		netlink_set_err(init_net.genl_sock, 0,
1646 				ovs_dp_vport_multicast_group.id, err);
1647 		return 0;
1648 	}
1649 
1650 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1651 		    ovs_dp_vport_multicast_group.id, info->nlhdr, GFP_KERNEL);
1652 
1653 exit_unlock:
1654 	rtnl_unlock();
1655 	return err;
1656 }
1657 
1658 static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info)
1659 {
1660 	struct nlattr **a = info->attrs;
1661 	struct sk_buff *reply;
1662 	struct vport *vport;
1663 	int err;
1664 
1665 	rtnl_lock();
1666 	vport = lookup_vport(info->userhdr, a);
1667 	err = PTR_ERR(vport);
1668 	if (IS_ERR(vport))
1669 		goto exit_unlock;
1670 
1671 	if (vport->port_no == OVSP_LOCAL) {
1672 		err = -EINVAL;
1673 		goto exit_unlock;
1674 	}
1675 
1676 	reply = ovs_vport_cmd_build_info(vport, info->snd_pid, info->snd_seq,
1677 					 OVS_VPORT_CMD_DEL);
1678 	err = PTR_ERR(reply);
1679 	if (IS_ERR(reply))
1680 		goto exit_unlock;
1681 
1682 	ovs_dp_detach_port(vport);
1683 
1684 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1685 		    ovs_dp_vport_multicast_group.id, info->nlhdr, GFP_KERNEL);
1686 
1687 exit_unlock:
1688 	rtnl_unlock();
1689 	return err;
1690 }
1691 
1692 static int ovs_vport_cmd_get(struct sk_buff *skb, struct genl_info *info)
1693 {
1694 	struct nlattr **a = info->attrs;
1695 	struct ovs_header *ovs_header = info->userhdr;
1696 	struct sk_buff *reply;
1697 	struct vport *vport;
1698 	int err;
1699 
1700 	rcu_read_lock();
1701 	vport = lookup_vport(ovs_header, a);
1702 	err = PTR_ERR(vport);
1703 	if (IS_ERR(vport))
1704 		goto exit_unlock;
1705 
1706 	reply = ovs_vport_cmd_build_info(vport, info->snd_pid, info->snd_seq,
1707 					 OVS_VPORT_CMD_NEW);
1708 	err = PTR_ERR(reply);
1709 	if (IS_ERR(reply))
1710 		goto exit_unlock;
1711 
1712 	rcu_read_unlock();
1713 
1714 	return genlmsg_reply(reply, info);
1715 
1716 exit_unlock:
1717 	rcu_read_unlock();
1718 	return err;
1719 }
1720 
1721 static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1722 {
1723 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1724 	struct datapath *dp;
1725 	u32 port_no;
1726 	int retval;
1727 
1728 	dp = get_dp(ovs_header->dp_ifindex);
1729 	if (!dp)
1730 		return -ENODEV;
1731 
1732 	rcu_read_lock();
1733 	for (port_no = cb->args[0]; port_no < DP_MAX_PORTS; port_no++) {
1734 		struct vport *vport;
1735 
1736 		vport = rcu_dereference(dp->ports[port_no]);
1737 		if (!vport)
1738 			continue;
1739 
1740 		if (ovs_vport_cmd_fill_info(vport, skb, NETLINK_CB(cb->skb).pid,
1741 					    cb->nlh->nlmsg_seq, NLM_F_MULTI,
1742 					    OVS_VPORT_CMD_NEW) < 0)
1743 			break;
1744 	}
1745 	rcu_read_unlock();
1746 
1747 	cb->args[0] = port_no;
1748 	retval = skb->len;
1749 
1750 	return retval;
1751 }
1752 
1753 static void rehash_flow_table(struct work_struct *work)
1754 {
1755 	struct datapath *dp;
1756 
1757 	genl_lock();
1758 
1759 	list_for_each_entry(dp, &dps, list_node) {
1760 		struct flow_table *old_table = genl_dereference(dp->table);
1761 		struct flow_table *new_table;
1762 
1763 		new_table = ovs_flow_tbl_rehash(old_table);
1764 		if (!IS_ERR(new_table)) {
1765 			rcu_assign_pointer(dp->table, new_table);
1766 			ovs_flow_tbl_deferred_destroy(old_table);
1767 		}
1768 	}
1769 
1770 	genl_unlock();
1771 
1772 	schedule_delayed_work(&rehash_flow_wq, REHASH_FLOW_INTERVAL);
1773 }
1774 
1775 static struct genl_ops dp_vport_genl_ops[] = {
1776 	{ .cmd = OVS_VPORT_CMD_NEW,
1777 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1778 	  .policy = vport_policy,
1779 	  .doit = ovs_vport_cmd_new
1780 	},
1781 	{ .cmd = OVS_VPORT_CMD_DEL,
1782 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1783 	  .policy = vport_policy,
1784 	  .doit = ovs_vport_cmd_del
1785 	},
1786 	{ .cmd = OVS_VPORT_CMD_GET,
1787 	  .flags = 0,		    /* OK for unprivileged users. */
1788 	  .policy = vport_policy,
1789 	  .doit = ovs_vport_cmd_get,
1790 	  .dumpit = ovs_vport_cmd_dump
1791 	},
1792 	{ .cmd = OVS_VPORT_CMD_SET,
1793 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1794 	  .policy = vport_policy,
1795 	  .doit = ovs_vport_cmd_set,
1796 	},
1797 };
1798 
1799 struct genl_family_and_ops {
1800 	struct genl_family *family;
1801 	struct genl_ops *ops;
1802 	int n_ops;
1803 	struct genl_multicast_group *group;
1804 };
1805 
1806 static const struct genl_family_and_ops dp_genl_families[] = {
1807 	{ &dp_datapath_genl_family,
1808 	  dp_datapath_genl_ops, ARRAY_SIZE(dp_datapath_genl_ops),
1809 	  &ovs_dp_datapath_multicast_group },
1810 	{ &dp_vport_genl_family,
1811 	  dp_vport_genl_ops, ARRAY_SIZE(dp_vport_genl_ops),
1812 	  &ovs_dp_vport_multicast_group },
1813 	{ &dp_flow_genl_family,
1814 	  dp_flow_genl_ops, ARRAY_SIZE(dp_flow_genl_ops),
1815 	  &ovs_dp_flow_multicast_group },
1816 	{ &dp_packet_genl_family,
1817 	  dp_packet_genl_ops, ARRAY_SIZE(dp_packet_genl_ops),
1818 	  NULL },
1819 };
1820 
1821 static void dp_unregister_genl(int n_families)
1822 {
1823 	int i;
1824 
1825 	for (i = 0; i < n_families; i++)
1826 		genl_unregister_family(dp_genl_families[i].family);
1827 }
1828 
1829 static int dp_register_genl(void)
1830 {
1831 	int n_registered;
1832 	int err;
1833 	int i;
1834 
1835 	n_registered = 0;
1836 	for (i = 0; i < ARRAY_SIZE(dp_genl_families); i++) {
1837 		const struct genl_family_and_ops *f = &dp_genl_families[i];
1838 
1839 		err = genl_register_family_with_ops(f->family, f->ops,
1840 						    f->n_ops);
1841 		if (err)
1842 			goto error;
1843 		n_registered++;
1844 
1845 		if (f->group) {
1846 			err = genl_register_mc_group(f->family, f->group);
1847 			if (err)
1848 				goto error;
1849 		}
1850 	}
1851 
1852 	return 0;
1853 
1854 error:
1855 	dp_unregister_genl(n_registered);
1856 	return err;
1857 }
1858 
1859 static int __init dp_init(void)
1860 {
1861 	struct sk_buff *dummy_skb;
1862 	int err;
1863 
1864 	BUILD_BUG_ON(sizeof(struct ovs_skb_cb) > sizeof(dummy_skb->cb));
1865 
1866 	pr_info("Open vSwitch switching datapath\n");
1867 
1868 	err = ovs_flow_init();
1869 	if (err)
1870 		goto error;
1871 
1872 	err = ovs_vport_init();
1873 	if (err)
1874 		goto error_flow_exit;
1875 
1876 	err = register_netdevice_notifier(&ovs_dp_device_notifier);
1877 	if (err)
1878 		goto error_vport_exit;
1879 
1880 	err = dp_register_genl();
1881 	if (err < 0)
1882 		goto error_unreg_notifier;
1883 
1884 	schedule_delayed_work(&rehash_flow_wq, REHASH_FLOW_INTERVAL);
1885 
1886 	return 0;
1887 
1888 error_unreg_notifier:
1889 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
1890 error_vport_exit:
1891 	ovs_vport_exit();
1892 error_flow_exit:
1893 	ovs_flow_exit();
1894 error:
1895 	return err;
1896 }
1897 
1898 static void dp_cleanup(void)
1899 {
1900 	cancel_delayed_work_sync(&rehash_flow_wq);
1901 	rcu_barrier();
1902 	dp_unregister_genl(ARRAY_SIZE(dp_genl_families));
1903 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
1904 	ovs_vport_exit();
1905 	ovs_flow_exit();
1906 }
1907 
1908 module_init(dp_init);
1909 module_exit(dp_cleanup);
1910 
1911 MODULE_DESCRIPTION("Open vSwitch switching datapath");
1912 MODULE_LICENSE("GPL");
1913