xref: /linux/net/openvswitch/datapath.c (revision a429638cac1e5c656818a45aaff78df7b743004e)
1 /*
2  * Copyright (c) 2007-2011 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/version.h>
40 #include <linux/ethtool.h>
41 #include <linux/wait.h>
42 #include <asm/system.h>
43 #include <asm/div64.h>
44 #include <linux/highmem.h>
45 #include <linux/netfilter_bridge.h>
46 #include <linux/netfilter_ipv4.h>
47 #include <linux/inetdevice.h>
48 #include <linux/list.h>
49 #include <linux/openvswitch.h>
50 #include <linux/rculist.h>
51 #include <linux/dmi.h>
52 #include <linux/workqueue.h>
53 #include <net/genetlink.h>
54 
55 #include "datapath.h"
56 #include "flow.h"
57 #include "vport-internal_dev.h"
58 
59 /**
60  * DOC: Locking:
61  *
62  * Writes to device state (add/remove datapath, port, set operations on vports,
63  * etc.) are protected by RTNL.
64  *
65  * Writes to other state (flow table modifications, set miscellaneous datapath
66  * parameters, etc.) are protected by genl_mutex.  The RTNL lock nests inside
67  * genl_mutex.
68  *
69  * Reads are protected by RCU.
70  *
71  * There are a few special cases (mostly stats) that have their own
72  * synchronization but they nest under all of above and don't interact with
73  * each other.
74  */
75 
76 /* Global list of datapaths to enable dumping them all out.
77  * Protected by genl_mutex.
78  */
79 static LIST_HEAD(dps);
80 
81 #define REHASH_FLOW_INTERVAL (10 * 60 * HZ)
82 static void rehash_flow_table(struct work_struct *work);
83 static DECLARE_DELAYED_WORK(rehash_flow_wq, rehash_flow_table);
84 
85 static struct vport *new_vport(const struct vport_parms *);
86 static int queue_gso_packets(int dp_ifindex, struct sk_buff *,
87 			     const struct dp_upcall_info *);
88 static int queue_userspace_packet(int dp_ifindex, struct sk_buff *,
89 				  const struct dp_upcall_info *);
90 
91 /* Must be called with rcu_read_lock, genl_mutex, or RTNL lock. */
92 static struct datapath *get_dp(int dp_ifindex)
93 {
94 	struct datapath *dp = NULL;
95 	struct net_device *dev;
96 
97 	rcu_read_lock();
98 	dev = dev_get_by_index_rcu(&init_net, dp_ifindex);
99 	if (dev) {
100 		struct vport *vport = ovs_internal_dev_get_vport(dev);
101 		if (vport)
102 			dp = vport->dp;
103 	}
104 	rcu_read_unlock();
105 
106 	return dp;
107 }
108 
109 /* Must be called with rcu_read_lock or RTNL lock. */
110 const char *ovs_dp_name(const struct datapath *dp)
111 {
112 	struct vport *vport = rcu_dereference_rtnl(dp->ports[OVSP_LOCAL]);
113 	return vport->ops->get_name(vport);
114 }
115 
116 static int get_dpifindex(struct datapath *dp)
117 {
118 	struct vport *local;
119 	int ifindex;
120 
121 	rcu_read_lock();
122 
123 	local = rcu_dereference(dp->ports[OVSP_LOCAL]);
124 	if (local)
125 		ifindex = local->ops->get_ifindex(local);
126 	else
127 		ifindex = 0;
128 
129 	rcu_read_unlock();
130 
131 	return ifindex;
132 }
133 
134 static void destroy_dp_rcu(struct rcu_head *rcu)
135 {
136 	struct datapath *dp = container_of(rcu, struct datapath, rcu);
137 
138 	ovs_flow_tbl_destroy((__force struct flow_table *)dp->table);
139 	free_percpu(dp->stats_percpu);
140 	kfree(dp);
141 }
142 
143 /* Called with RTNL lock and genl_lock. */
144 static struct vport *new_vport(const struct vport_parms *parms)
145 {
146 	struct vport *vport;
147 
148 	vport = ovs_vport_add(parms);
149 	if (!IS_ERR(vport)) {
150 		struct datapath *dp = parms->dp;
151 
152 		rcu_assign_pointer(dp->ports[parms->port_no], vport);
153 		list_add(&vport->node, &dp->port_list);
154 	}
155 
156 	return vport;
157 }
158 
159 /* Called with RTNL lock. */
160 void ovs_dp_detach_port(struct vport *p)
161 {
162 	ASSERT_RTNL();
163 
164 	/* First drop references to device. */
165 	list_del(&p->node);
166 	rcu_assign_pointer(p->dp->ports[p->port_no], NULL);
167 
168 	/* Then destroy it. */
169 	ovs_vport_del(p);
170 }
171 
172 /* Must be called with rcu_read_lock. */
173 void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
174 {
175 	struct datapath *dp = p->dp;
176 	struct sw_flow *flow;
177 	struct dp_stats_percpu *stats;
178 	struct sw_flow_key key;
179 	u64 *stats_counter;
180 	int error;
181 	int key_len;
182 
183 	stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id());
184 
185 	/* Extract flow from 'skb' into 'key'. */
186 	error = ovs_flow_extract(skb, p->port_no, &key, &key_len);
187 	if (unlikely(error)) {
188 		kfree_skb(skb);
189 		return;
190 	}
191 
192 	/* Look up flow. */
193 	flow = ovs_flow_tbl_lookup(rcu_dereference(dp->table), &key, key_len);
194 	if (unlikely(!flow)) {
195 		struct dp_upcall_info upcall;
196 
197 		upcall.cmd = OVS_PACKET_CMD_MISS;
198 		upcall.key = &key;
199 		upcall.userdata = NULL;
200 		upcall.pid = p->upcall_pid;
201 		ovs_dp_upcall(dp, skb, &upcall);
202 		consume_skb(skb);
203 		stats_counter = &stats->n_missed;
204 		goto out;
205 	}
206 
207 	OVS_CB(skb)->flow = flow;
208 
209 	stats_counter = &stats->n_hit;
210 	ovs_flow_used(OVS_CB(skb)->flow, skb);
211 	ovs_execute_actions(dp, skb);
212 
213 out:
214 	/* Update datapath statistics. */
215 	u64_stats_update_begin(&stats->sync);
216 	(*stats_counter)++;
217 	u64_stats_update_end(&stats->sync);
218 }
219 
220 static struct genl_family dp_packet_genl_family = {
221 	.id = GENL_ID_GENERATE,
222 	.hdrsize = sizeof(struct ovs_header),
223 	.name = OVS_PACKET_FAMILY,
224 	.version = OVS_PACKET_VERSION,
225 	.maxattr = OVS_PACKET_ATTR_MAX
226 };
227 
228 int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
229 	      const struct dp_upcall_info *upcall_info)
230 {
231 	struct dp_stats_percpu *stats;
232 	int dp_ifindex;
233 	int err;
234 
235 	if (upcall_info->pid == 0) {
236 		err = -ENOTCONN;
237 		goto err;
238 	}
239 
240 	dp_ifindex = get_dpifindex(dp);
241 	if (!dp_ifindex) {
242 		err = -ENODEV;
243 		goto err;
244 	}
245 
246 	if (!skb_is_gso(skb))
247 		err = queue_userspace_packet(dp_ifindex, skb, upcall_info);
248 	else
249 		err = queue_gso_packets(dp_ifindex, skb, upcall_info);
250 	if (err)
251 		goto err;
252 
253 	return 0;
254 
255 err:
256 	stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id());
257 
258 	u64_stats_update_begin(&stats->sync);
259 	stats->n_lost++;
260 	u64_stats_update_end(&stats->sync);
261 
262 	return err;
263 }
264 
265 static int queue_gso_packets(int dp_ifindex, struct sk_buff *skb,
266 			     const struct dp_upcall_info *upcall_info)
267 {
268 	struct dp_upcall_info later_info;
269 	struct sw_flow_key later_key;
270 	struct sk_buff *segs, *nskb;
271 	int err;
272 
273 	segs = skb_gso_segment(skb, NETIF_F_SG | NETIF_F_HW_CSUM);
274 	if (IS_ERR(skb))
275 		return PTR_ERR(skb);
276 
277 	/* Queue all of the segments. */
278 	skb = segs;
279 	do {
280 		err = queue_userspace_packet(dp_ifindex, skb, upcall_info);
281 		if (err)
282 			break;
283 
284 		if (skb == segs && skb_shinfo(skb)->gso_type & SKB_GSO_UDP) {
285 			/* The initial flow key extracted by ovs_flow_extract()
286 			 * in this case is for a first fragment, so we need to
287 			 * properly mark later fragments.
288 			 */
289 			later_key = *upcall_info->key;
290 			later_key.ip.frag = OVS_FRAG_TYPE_LATER;
291 
292 			later_info = *upcall_info;
293 			later_info.key = &later_key;
294 			upcall_info = &later_info;
295 		}
296 	} while ((skb = skb->next));
297 
298 	/* Free all of the segments. */
299 	skb = segs;
300 	do {
301 		nskb = skb->next;
302 		if (err)
303 			kfree_skb(skb);
304 		else
305 			consume_skb(skb);
306 	} while ((skb = nskb));
307 	return err;
308 }
309 
310 static int queue_userspace_packet(int dp_ifindex, struct sk_buff *skb,
311 				  const struct dp_upcall_info *upcall_info)
312 {
313 	struct ovs_header *upcall;
314 	struct sk_buff *nskb = NULL;
315 	struct sk_buff *user_skb; /* to be queued to userspace */
316 	struct nlattr *nla;
317 	unsigned int len;
318 	int err;
319 
320 	if (vlan_tx_tag_present(skb)) {
321 		nskb = skb_clone(skb, GFP_ATOMIC);
322 		if (!nskb)
323 			return -ENOMEM;
324 
325 		nskb = __vlan_put_tag(nskb, vlan_tx_tag_get(nskb));
326 		if (!skb)
327 			return -ENOMEM;
328 
329 		nskb->vlan_tci = 0;
330 		skb = nskb;
331 	}
332 
333 	if (nla_attr_size(skb->len) > USHRT_MAX) {
334 		err = -EFBIG;
335 		goto out;
336 	}
337 
338 	len = sizeof(struct ovs_header);
339 	len += nla_total_size(skb->len);
340 	len += nla_total_size(FLOW_BUFSIZE);
341 	if (upcall_info->cmd == OVS_PACKET_CMD_ACTION)
342 		len += nla_total_size(8);
343 
344 	user_skb = genlmsg_new(len, GFP_ATOMIC);
345 	if (!user_skb) {
346 		err = -ENOMEM;
347 		goto out;
348 	}
349 
350 	upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
351 			     0, upcall_info->cmd);
352 	upcall->dp_ifindex = dp_ifindex;
353 
354 	nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_KEY);
355 	ovs_flow_to_nlattrs(upcall_info->key, user_skb);
356 	nla_nest_end(user_skb, nla);
357 
358 	if (upcall_info->userdata)
359 		nla_put_u64(user_skb, OVS_PACKET_ATTR_USERDATA,
360 			    nla_get_u64(upcall_info->userdata));
361 
362 	nla = __nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, skb->len);
363 
364 	skb_copy_and_csum_dev(skb, nla_data(nla));
365 
366 	err = genlmsg_unicast(&init_net, user_skb, upcall_info->pid);
367 
368 out:
369 	kfree_skb(nskb);
370 	return err;
371 }
372 
373 /* Called with genl_mutex. */
374 static int flush_flows(int dp_ifindex)
375 {
376 	struct flow_table *old_table;
377 	struct flow_table *new_table;
378 	struct datapath *dp;
379 
380 	dp = get_dp(dp_ifindex);
381 	if (!dp)
382 		return -ENODEV;
383 
384 	old_table = genl_dereference(dp->table);
385 	new_table = ovs_flow_tbl_alloc(TBL_MIN_BUCKETS);
386 	if (!new_table)
387 		return -ENOMEM;
388 
389 	rcu_assign_pointer(dp->table, new_table);
390 
391 	ovs_flow_tbl_deferred_destroy(old_table);
392 	return 0;
393 }
394 
395 static int validate_actions(const struct nlattr *attr,
396 				const struct sw_flow_key *key, int depth);
397 
398 static int validate_sample(const struct nlattr *attr,
399 				const struct sw_flow_key *key, int depth)
400 {
401 	const struct nlattr *attrs[OVS_SAMPLE_ATTR_MAX + 1];
402 	const struct nlattr *probability, *actions;
403 	const struct nlattr *a;
404 	int rem;
405 
406 	memset(attrs, 0, sizeof(attrs));
407 	nla_for_each_nested(a, attr, rem) {
408 		int type = nla_type(a);
409 		if (!type || type > OVS_SAMPLE_ATTR_MAX || attrs[type])
410 			return -EINVAL;
411 		attrs[type] = a;
412 	}
413 	if (rem)
414 		return -EINVAL;
415 
416 	probability = attrs[OVS_SAMPLE_ATTR_PROBABILITY];
417 	if (!probability || nla_len(probability) != sizeof(u32))
418 		return -EINVAL;
419 
420 	actions = attrs[OVS_SAMPLE_ATTR_ACTIONS];
421 	if (!actions || (nla_len(actions) && nla_len(actions) < NLA_HDRLEN))
422 		return -EINVAL;
423 	return validate_actions(actions, key, depth + 1);
424 }
425 
426 static int validate_set(const struct nlattr *a,
427 			const struct sw_flow_key *flow_key)
428 {
429 	const struct nlattr *ovs_key = nla_data(a);
430 	int key_type = nla_type(ovs_key);
431 
432 	/* There can be only one key in a action */
433 	if (nla_total_size(nla_len(ovs_key)) != nla_len(a))
434 		return -EINVAL;
435 
436 	if (key_type > OVS_KEY_ATTR_MAX ||
437 	    nla_len(ovs_key) != ovs_key_lens[key_type])
438 		return -EINVAL;
439 
440 	switch (key_type) {
441 	const struct ovs_key_ipv4 *ipv4_key;
442 
443 	case OVS_KEY_ATTR_PRIORITY:
444 	case OVS_KEY_ATTR_ETHERNET:
445 		break;
446 
447 	case OVS_KEY_ATTR_IPV4:
448 		if (flow_key->eth.type != htons(ETH_P_IP))
449 			return -EINVAL;
450 
451 		if (!flow_key->ipv4.addr.src || !flow_key->ipv4.addr.dst)
452 			return -EINVAL;
453 
454 		ipv4_key = nla_data(ovs_key);
455 		if (ipv4_key->ipv4_proto != flow_key->ip.proto)
456 			return -EINVAL;
457 
458 		if (ipv4_key->ipv4_frag != flow_key->ip.frag)
459 			return -EINVAL;
460 
461 		break;
462 
463 	case OVS_KEY_ATTR_TCP:
464 		if (flow_key->ip.proto != IPPROTO_TCP)
465 			return -EINVAL;
466 
467 		if (!flow_key->ipv4.tp.src || !flow_key->ipv4.tp.dst)
468 			return -EINVAL;
469 
470 		break;
471 
472 	case OVS_KEY_ATTR_UDP:
473 		if (flow_key->ip.proto != IPPROTO_UDP)
474 			return -EINVAL;
475 
476 		if (!flow_key->ipv4.tp.src || !flow_key->ipv4.tp.dst)
477 			return -EINVAL;
478 		break;
479 
480 	default:
481 		return -EINVAL;
482 	}
483 
484 	return 0;
485 }
486 
487 static int validate_userspace(const struct nlattr *attr)
488 {
489 	static const struct nla_policy userspace_policy[OVS_USERSPACE_ATTR_MAX + 1] =	{
490 		[OVS_USERSPACE_ATTR_PID] = {.type = NLA_U32 },
491 		[OVS_USERSPACE_ATTR_USERDATA] = {.type = NLA_U64 },
492 	};
493 	struct nlattr *a[OVS_USERSPACE_ATTR_MAX + 1];
494 	int error;
495 
496 	error = nla_parse_nested(a, OVS_USERSPACE_ATTR_MAX,
497 				 attr, userspace_policy);
498 	if (error)
499 		return error;
500 
501 	if (!a[OVS_USERSPACE_ATTR_PID] ||
502 	    !nla_get_u32(a[OVS_USERSPACE_ATTR_PID]))
503 		return -EINVAL;
504 
505 	return 0;
506 }
507 
508 static int validate_actions(const struct nlattr *attr,
509 				const struct sw_flow_key *key,  int depth)
510 {
511 	const struct nlattr *a;
512 	int rem, err;
513 
514 	if (depth >= SAMPLE_ACTION_DEPTH)
515 		return -EOVERFLOW;
516 
517 	nla_for_each_nested(a, attr, rem) {
518 		/* Expected argument lengths, (u32)-1 for variable length. */
519 		static const u32 action_lens[OVS_ACTION_ATTR_MAX + 1] = {
520 			[OVS_ACTION_ATTR_OUTPUT] = sizeof(u32),
521 			[OVS_ACTION_ATTR_USERSPACE] = (u32)-1,
522 			[OVS_ACTION_ATTR_PUSH_VLAN] = sizeof(struct ovs_action_push_vlan),
523 			[OVS_ACTION_ATTR_POP_VLAN] = 0,
524 			[OVS_ACTION_ATTR_SET] = (u32)-1,
525 			[OVS_ACTION_ATTR_SAMPLE] = (u32)-1
526 		};
527 		const struct ovs_action_push_vlan *vlan;
528 		int type = nla_type(a);
529 
530 		if (type > OVS_ACTION_ATTR_MAX ||
531 		    (action_lens[type] != nla_len(a) &&
532 		     action_lens[type] != (u32)-1))
533 			return -EINVAL;
534 
535 		switch (type) {
536 		case OVS_ACTION_ATTR_UNSPEC:
537 			return -EINVAL;
538 
539 		case OVS_ACTION_ATTR_USERSPACE:
540 			err = validate_userspace(a);
541 			if (err)
542 				return err;
543 			break;
544 
545 		case OVS_ACTION_ATTR_OUTPUT:
546 			if (nla_get_u32(a) >= DP_MAX_PORTS)
547 				return -EINVAL;
548 			break;
549 
550 
551 		case OVS_ACTION_ATTR_POP_VLAN:
552 			break;
553 
554 		case OVS_ACTION_ATTR_PUSH_VLAN:
555 			vlan = nla_data(a);
556 			if (vlan->vlan_tpid != htons(ETH_P_8021Q))
557 				return -EINVAL;
558 			if (!(vlan->vlan_tci & htons(VLAN_TAG_PRESENT)))
559 				return -EINVAL;
560 			break;
561 
562 		case OVS_ACTION_ATTR_SET:
563 			err = validate_set(a, key);
564 			if (err)
565 				return err;
566 			break;
567 
568 		case OVS_ACTION_ATTR_SAMPLE:
569 			err = validate_sample(a, key, depth);
570 			if (err)
571 				return err;
572 			break;
573 
574 		default:
575 			return -EINVAL;
576 		}
577 	}
578 
579 	if (rem > 0)
580 		return -EINVAL;
581 
582 	return 0;
583 }
584 
585 static void clear_stats(struct sw_flow *flow)
586 {
587 	flow->used = 0;
588 	flow->tcp_flags = 0;
589 	flow->packet_count = 0;
590 	flow->byte_count = 0;
591 }
592 
593 static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
594 {
595 	struct ovs_header *ovs_header = info->userhdr;
596 	struct nlattr **a = info->attrs;
597 	struct sw_flow_actions *acts;
598 	struct sk_buff *packet;
599 	struct sw_flow *flow;
600 	struct datapath *dp;
601 	struct ethhdr *eth;
602 	int len;
603 	int err;
604 	int key_len;
605 
606 	err = -EINVAL;
607 	if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] ||
608 	    !a[OVS_PACKET_ATTR_ACTIONS] ||
609 	    nla_len(a[OVS_PACKET_ATTR_PACKET]) < ETH_HLEN)
610 		goto err;
611 
612 	len = nla_len(a[OVS_PACKET_ATTR_PACKET]);
613 	packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL);
614 	err = -ENOMEM;
615 	if (!packet)
616 		goto err;
617 	skb_reserve(packet, NET_IP_ALIGN);
618 
619 	memcpy(__skb_put(packet, len), nla_data(a[OVS_PACKET_ATTR_PACKET]), len);
620 
621 	skb_reset_mac_header(packet);
622 	eth = eth_hdr(packet);
623 
624 	/* Normally, setting the skb 'protocol' field would be handled by a
625 	 * call to eth_type_trans(), but it assumes there's a sending
626 	 * device, which we may not have. */
627 	if (ntohs(eth->h_proto) >= 1536)
628 		packet->protocol = eth->h_proto;
629 	else
630 		packet->protocol = htons(ETH_P_802_2);
631 
632 	/* Build an sw_flow for sending this packet. */
633 	flow = ovs_flow_alloc();
634 	err = PTR_ERR(flow);
635 	if (IS_ERR(flow))
636 		goto err_kfree_skb;
637 
638 	err = ovs_flow_extract(packet, -1, &flow->key, &key_len);
639 	if (err)
640 		goto err_flow_free;
641 
642 	err = ovs_flow_metadata_from_nlattrs(&flow->key.phy.priority,
643 					     &flow->key.phy.in_port,
644 					     a[OVS_PACKET_ATTR_KEY]);
645 	if (err)
646 		goto err_flow_free;
647 
648 	err = validate_actions(a[OVS_PACKET_ATTR_ACTIONS], &flow->key, 0);
649 	if (err)
650 		goto err_flow_free;
651 
652 	flow->hash = ovs_flow_hash(&flow->key, key_len);
653 
654 	acts = ovs_flow_actions_alloc(a[OVS_PACKET_ATTR_ACTIONS]);
655 	err = PTR_ERR(acts);
656 	if (IS_ERR(acts))
657 		goto err_flow_free;
658 	rcu_assign_pointer(flow->sf_acts, acts);
659 
660 	OVS_CB(packet)->flow = flow;
661 	packet->priority = flow->key.phy.priority;
662 
663 	rcu_read_lock();
664 	dp = get_dp(ovs_header->dp_ifindex);
665 	err = -ENODEV;
666 	if (!dp)
667 		goto err_unlock;
668 
669 	local_bh_disable();
670 	err = ovs_execute_actions(dp, packet);
671 	local_bh_enable();
672 	rcu_read_unlock();
673 
674 	ovs_flow_free(flow);
675 	return err;
676 
677 err_unlock:
678 	rcu_read_unlock();
679 err_flow_free:
680 	ovs_flow_free(flow);
681 err_kfree_skb:
682 	kfree_skb(packet);
683 err:
684 	return err;
685 }
686 
687 static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = {
688 	[OVS_PACKET_ATTR_PACKET] = { .type = NLA_UNSPEC },
689 	[OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED },
690 	[OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED },
691 };
692 
693 static struct genl_ops dp_packet_genl_ops[] = {
694 	{ .cmd = OVS_PACKET_CMD_EXECUTE,
695 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
696 	  .policy = packet_policy,
697 	  .doit = ovs_packet_cmd_execute
698 	}
699 };
700 
701 static void get_dp_stats(struct datapath *dp, struct ovs_dp_stats *stats)
702 {
703 	int i;
704 	struct flow_table *table = genl_dereference(dp->table);
705 
706 	stats->n_flows = ovs_flow_tbl_count(table);
707 
708 	stats->n_hit = stats->n_missed = stats->n_lost = 0;
709 	for_each_possible_cpu(i) {
710 		const struct dp_stats_percpu *percpu_stats;
711 		struct dp_stats_percpu local_stats;
712 		unsigned int start;
713 
714 		percpu_stats = per_cpu_ptr(dp->stats_percpu, i);
715 
716 		do {
717 			start = u64_stats_fetch_begin_bh(&percpu_stats->sync);
718 			local_stats = *percpu_stats;
719 		} while (u64_stats_fetch_retry_bh(&percpu_stats->sync, start));
720 
721 		stats->n_hit += local_stats.n_hit;
722 		stats->n_missed += local_stats.n_missed;
723 		stats->n_lost += local_stats.n_lost;
724 	}
725 }
726 
727 static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = {
728 	[OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED },
729 	[OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED },
730 	[OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG },
731 };
732 
733 static struct genl_family dp_flow_genl_family = {
734 	.id = GENL_ID_GENERATE,
735 	.hdrsize = sizeof(struct ovs_header),
736 	.name = OVS_FLOW_FAMILY,
737 	.version = OVS_FLOW_VERSION,
738 	.maxattr = OVS_FLOW_ATTR_MAX
739 };
740 
741 static struct genl_multicast_group ovs_dp_flow_multicast_group = {
742 	.name = OVS_FLOW_MCGROUP
743 };
744 
745 /* Called with genl_lock. */
746 static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp,
747 				  struct sk_buff *skb, u32 pid,
748 				  u32 seq, u32 flags, u8 cmd)
749 {
750 	const int skb_orig_len = skb->len;
751 	const struct sw_flow_actions *sf_acts;
752 	struct ovs_flow_stats stats;
753 	struct ovs_header *ovs_header;
754 	struct nlattr *nla;
755 	unsigned long used;
756 	u8 tcp_flags;
757 	int err;
758 
759 	sf_acts = rcu_dereference_protected(flow->sf_acts,
760 					    lockdep_genl_is_held());
761 
762 	ovs_header = genlmsg_put(skb, pid, seq, &dp_flow_genl_family, flags, cmd);
763 	if (!ovs_header)
764 		return -EMSGSIZE;
765 
766 	ovs_header->dp_ifindex = get_dpifindex(dp);
767 
768 	nla = nla_nest_start(skb, OVS_FLOW_ATTR_KEY);
769 	if (!nla)
770 		goto nla_put_failure;
771 	err = ovs_flow_to_nlattrs(&flow->key, skb);
772 	if (err)
773 		goto error;
774 	nla_nest_end(skb, nla);
775 
776 	spin_lock_bh(&flow->lock);
777 	used = flow->used;
778 	stats.n_packets = flow->packet_count;
779 	stats.n_bytes = flow->byte_count;
780 	tcp_flags = flow->tcp_flags;
781 	spin_unlock_bh(&flow->lock);
782 
783 	if (used)
784 		NLA_PUT_U64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used));
785 
786 	if (stats.n_packets)
787 		NLA_PUT(skb, OVS_FLOW_ATTR_STATS,
788 			sizeof(struct ovs_flow_stats), &stats);
789 
790 	if (tcp_flags)
791 		NLA_PUT_U8(skb, OVS_FLOW_ATTR_TCP_FLAGS, tcp_flags);
792 
793 	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
794 	 * this is the first flow to be dumped into 'skb'.  This is unusual for
795 	 * Netlink but individual action lists can be longer than
796 	 * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this.
797 	 * The userspace caller can always fetch the actions separately if it
798 	 * really wants them.  (Most userspace callers in fact don't care.)
799 	 *
800 	 * This can only fail for dump operations because the skb is always
801 	 * properly sized for single flows.
802 	 */
803 	err = nla_put(skb, OVS_FLOW_ATTR_ACTIONS, sf_acts->actions_len,
804 		      sf_acts->actions);
805 	if (err < 0 && skb_orig_len)
806 		goto error;
807 
808 	return genlmsg_end(skb, ovs_header);
809 
810 nla_put_failure:
811 	err = -EMSGSIZE;
812 error:
813 	genlmsg_cancel(skb, ovs_header);
814 	return err;
815 }
816 
817 static struct sk_buff *ovs_flow_cmd_alloc_info(struct sw_flow *flow)
818 {
819 	const struct sw_flow_actions *sf_acts;
820 	int len;
821 
822 	sf_acts = rcu_dereference_protected(flow->sf_acts,
823 					    lockdep_genl_is_held());
824 
825 	/* OVS_FLOW_ATTR_KEY */
826 	len = nla_total_size(FLOW_BUFSIZE);
827 	/* OVS_FLOW_ATTR_ACTIONS */
828 	len += nla_total_size(sf_acts->actions_len);
829 	/* OVS_FLOW_ATTR_STATS */
830 	len += nla_total_size(sizeof(struct ovs_flow_stats));
831 	/* OVS_FLOW_ATTR_TCP_FLAGS */
832 	len += nla_total_size(1);
833 	/* OVS_FLOW_ATTR_USED */
834 	len += nla_total_size(8);
835 
836 	len += NLMSG_ALIGN(sizeof(struct ovs_header));
837 
838 	return genlmsg_new(len, GFP_KERNEL);
839 }
840 
841 static struct sk_buff *ovs_flow_cmd_build_info(struct sw_flow *flow,
842 					       struct datapath *dp,
843 					       u32 pid, u32 seq, u8 cmd)
844 {
845 	struct sk_buff *skb;
846 	int retval;
847 
848 	skb = ovs_flow_cmd_alloc_info(flow);
849 	if (!skb)
850 		return ERR_PTR(-ENOMEM);
851 
852 	retval = ovs_flow_cmd_fill_info(flow, dp, skb, pid, seq, 0, cmd);
853 	BUG_ON(retval < 0);
854 	return skb;
855 }
856 
857 static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
858 {
859 	struct nlattr **a = info->attrs;
860 	struct ovs_header *ovs_header = info->userhdr;
861 	struct sw_flow_key key;
862 	struct sw_flow *flow;
863 	struct sk_buff *reply;
864 	struct datapath *dp;
865 	struct flow_table *table;
866 	int error;
867 	int key_len;
868 
869 	/* Extract key. */
870 	error = -EINVAL;
871 	if (!a[OVS_FLOW_ATTR_KEY])
872 		goto error;
873 	error = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]);
874 	if (error)
875 		goto error;
876 
877 	/* Validate actions. */
878 	if (a[OVS_FLOW_ATTR_ACTIONS]) {
879 		error = validate_actions(a[OVS_FLOW_ATTR_ACTIONS], &key,  0);
880 		if (error)
881 			goto error;
882 	} else if (info->genlhdr->cmd == OVS_FLOW_CMD_NEW) {
883 		error = -EINVAL;
884 		goto error;
885 	}
886 
887 	dp = get_dp(ovs_header->dp_ifindex);
888 	error = -ENODEV;
889 	if (!dp)
890 		goto error;
891 
892 	table = genl_dereference(dp->table);
893 	flow = ovs_flow_tbl_lookup(table, &key, key_len);
894 	if (!flow) {
895 		struct sw_flow_actions *acts;
896 
897 		/* Bail out if we're not allowed to create a new flow. */
898 		error = -ENOENT;
899 		if (info->genlhdr->cmd == OVS_FLOW_CMD_SET)
900 			goto error;
901 
902 		/* Expand table, if necessary, to make room. */
903 		if (ovs_flow_tbl_need_to_expand(table)) {
904 			struct flow_table *new_table;
905 
906 			new_table = ovs_flow_tbl_expand(table);
907 			if (!IS_ERR(new_table)) {
908 				rcu_assign_pointer(dp->table, new_table);
909 				ovs_flow_tbl_deferred_destroy(table);
910 				table = genl_dereference(dp->table);
911 			}
912 		}
913 
914 		/* Allocate flow. */
915 		flow = ovs_flow_alloc();
916 		if (IS_ERR(flow)) {
917 			error = PTR_ERR(flow);
918 			goto error;
919 		}
920 		flow->key = key;
921 		clear_stats(flow);
922 
923 		/* Obtain actions. */
924 		acts = ovs_flow_actions_alloc(a[OVS_FLOW_ATTR_ACTIONS]);
925 		error = PTR_ERR(acts);
926 		if (IS_ERR(acts))
927 			goto error_free_flow;
928 		rcu_assign_pointer(flow->sf_acts, acts);
929 
930 		/* Put flow in bucket. */
931 		flow->hash = ovs_flow_hash(&key, key_len);
932 		ovs_flow_tbl_insert(table, flow);
933 
934 		reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid,
935 						info->snd_seq,
936 						OVS_FLOW_CMD_NEW);
937 	} else {
938 		/* We found a matching flow. */
939 		struct sw_flow_actions *old_acts;
940 		struct nlattr *acts_attrs;
941 
942 		/* Bail out if we're not allowed to modify an existing flow.
943 		 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
944 		 * because Generic Netlink treats the latter as a dump
945 		 * request.  We also accept NLM_F_EXCL in case that bug ever
946 		 * gets fixed.
947 		 */
948 		error = -EEXIST;
949 		if (info->genlhdr->cmd == OVS_FLOW_CMD_NEW &&
950 		    info->nlhdr->nlmsg_flags & (NLM_F_CREATE | NLM_F_EXCL))
951 			goto error;
952 
953 		/* Update actions. */
954 		old_acts = rcu_dereference_protected(flow->sf_acts,
955 						     lockdep_genl_is_held());
956 		acts_attrs = a[OVS_FLOW_ATTR_ACTIONS];
957 		if (acts_attrs &&
958 		   (old_acts->actions_len != nla_len(acts_attrs) ||
959 		   memcmp(old_acts->actions, nla_data(acts_attrs),
960 			  old_acts->actions_len))) {
961 			struct sw_flow_actions *new_acts;
962 
963 			new_acts = ovs_flow_actions_alloc(acts_attrs);
964 			error = PTR_ERR(new_acts);
965 			if (IS_ERR(new_acts))
966 				goto error;
967 
968 			rcu_assign_pointer(flow->sf_acts, new_acts);
969 			ovs_flow_deferred_free_acts(old_acts);
970 		}
971 
972 		reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid,
973 					       info->snd_seq, OVS_FLOW_CMD_NEW);
974 
975 		/* Clear stats. */
976 		if (a[OVS_FLOW_ATTR_CLEAR]) {
977 			spin_lock_bh(&flow->lock);
978 			clear_stats(flow);
979 			spin_unlock_bh(&flow->lock);
980 		}
981 	}
982 
983 	if (!IS_ERR(reply))
984 		genl_notify(reply, genl_info_net(info), info->snd_pid,
985 			   ovs_dp_flow_multicast_group.id, info->nlhdr,
986 			   GFP_KERNEL);
987 	else
988 		netlink_set_err(init_net.genl_sock, 0,
989 				ovs_dp_flow_multicast_group.id, PTR_ERR(reply));
990 	return 0;
991 
992 error_free_flow:
993 	ovs_flow_free(flow);
994 error:
995 	return error;
996 }
997 
998 static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
999 {
1000 	struct nlattr **a = info->attrs;
1001 	struct ovs_header *ovs_header = info->userhdr;
1002 	struct sw_flow_key key;
1003 	struct sk_buff *reply;
1004 	struct sw_flow *flow;
1005 	struct datapath *dp;
1006 	struct flow_table *table;
1007 	int err;
1008 	int key_len;
1009 
1010 	if (!a[OVS_FLOW_ATTR_KEY])
1011 		return -EINVAL;
1012 	err = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]);
1013 	if (err)
1014 		return err;
1015 
1016 	dp = get_dp(ovs_header->dp_ifindex);
1017 	if (!dp)
1018 		return -ENODEV;
1019 
1020 	table = genl_dereference(dp->table);
1021 	flow = ovs_flow_tbl_lookup(table, &key, key_len);
1022 	if (!flow)
1023 		return -ENOENT;
1024 
1025 	reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid,
1026 					info->snd_seq, OVS_FLOW_CMD_NEW);
1027 	if (IS_ERR(reply))
1028 		return PTR_ERR(reply);
1029 
1030 	return genlmsg_reply(reply, info);
1031 }
1032 
1033 static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
1034 {
1035 	struct nlattr **a = info->attrs;
1036 	struct ovs_header *ovs_header = info->userhdr;
1037 	struct sw_flow_key key;
1038 	struct sk_buff *reply;
1039 	struct sw_flow *flow;
1040 	struct datapath *dp;
1041 	struct flow_table *table;
1042 	int err;
1043 	int key_len;
1044 
1045 	if (!a[OVS_FLOW_ATTR_KEY])
1046 		return flush_flows(ovs_header->dp_ifindex);
1047 	err = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]);
1048 	if (err)
1049 		return err;
1050 
1051 	dp = get_dp(ovs_header->dp_ifindex);
1052 	if (!dp)
1053 		return -ENODEV;
1054 
1055 	table = genl_dereference(dp->table);
1056 	flow = ovs_flow_tbl_lookup(table, &key, key_len);
1057 	if (!flow)
1058 		return -ENOENT;
1059 
1060 	reply = ovs_flow_cmd_alloc_info(flow);
1061 	if (!reply)
1062 		return -ENOMEM;
1063 
1064 	ovs_flow_tbl_remove(table, flow);
1065 
1066 	err = ovs_flow_cmd_fill_info(flow, dp, reply, info->snd_pid,
1067 				     info->snd_seq, 0, OVS_FLOW_CMD_DEL);
1068 	BUG_ON(err < 0);
1069 
1070 	ovs_flow_deferred_free(flow);
1071 
1072 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1073 		    ovs_dp_flow_multicast_group.id, info->nlhdr, GFP_KERNEL);
1074 	return 0;
1075 }
1076 
1077 static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1078 {
1079 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1080 	struct datapath *dp;
1081 	struct flow_table *table;
1082 
1083 	dp = get_dp(ovs_header->dp_ifindex);
1084 	if (!dp)
1085 		return -ENODEV;
1086 
1087 	table = genl_dereference(dp->table);
1088 
1089 	for (;;) {
1090 		struct sw_flow *flow;
1091 		u32 bucket, obj;
1092 
1093 		bucket = cb->args[0];
1094 		obj = cb->args[1];
1095 		flow = ovs_flow_tbl_next(table, &bucket, &obj);
1096 		if (!flow)
1097 			break;
1098 
1099 		if (ovs_flow_cmd_fill_info(flow, dp, skb,
1100 					   NETLINK_CB(cb->skb).pid,
1101 					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
1102 					   OVS_FLOW_CMD_NEW) < 0)
1103 			break;
1104 
1105 		cb->args[0] = bucket;
1106 		cb->args[1] = obj;
1107 	}
1108 	return skb->len;
1109 }
1110 
1111 static struct genl_ops dp_flow_genl_ops[] = {
1112 	{ .cmd = OVS_FLOW_CMD_NEW,
1113 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1114 	  .policy = flow_policy,
1115 	  .doit = ovs_flow_cmd_new_or_set
1116 	},
1117 	{ .cmd = OVS_FLOW_CMD_DEL,
1118 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1119 	  .policy = flow_policy,
1120 	  .doit = ovs_flow_cmd_del
1121 	},
1122 	{ .cmd = OVS_FLOW_CMD_GET,
1123 	  .flags = 0,		    /* OK for unprivileged users. */
1124 	  .policy = flow_policy,
1125 	  .doit = ovs_flow_cmd_get,
1126 	  .dumpit = ovs_flow_cmd_dump
1127 	},
1128 	{ .cmd = OVS_FLOW_CMD_SET,
1129 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1130 	  .policy = flow_policy,
1131 	  .doit = ovs_flow_cmd_new_or_set,
1132 	},
1133 };
1134 
1135 static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
1136 	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1137 	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1138 };
1139 
1140 static struct genl_family dp_datapath_genl_family = {
1141 	.id = GENL_ID_GENERATE,
1142 	.hdrsize = sizeof(struct ovs_header),
1143 	.name = OVS_DATAPATH_FAMILY,
1144 	.version = OVS_DATAPATH_VERSION,
1145 	.maxattr = OVS_DP_ATTR_MAX
1146 };
1147 
1148 static struct genl_multicast_group ovs_dp_datapath_multicast_group = {
1149 	.name = OVS_DATAPATH_MCGROUP
1150 };
1151 
1152 static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
1153 				u32 pid, u32 seq, u32 flags, u8 cmd)
1154 {
1155 	struct ovs_header *ovs_header;
1156 	struct ovs_dp_stats dp_stats;
1157 	int err;
1158 
1159 	ovs_header = genlmsg_put(skb, pid, seq, &dp_datapath_genl_family,
1160 				   flags, cmd);
1161 	if (!ovs_header)
1162 		goto error;
1163 
1164 	ovs_header->dp_ifindex = get_dpifindex(dp);
1165 
1166 	rcu_read_lock();
1167 	err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp));
1168 	rcu_read_unlock();
1169 	if (err)
1170 		goto nla_put_failure;
1171 
1172 	get_dp_stats(dp, &dp_stats);
1173 	NLA_PUT(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats), &dp_stats);
1174 
1175 	return genlmsg_end(skb, ovs_header);
1176 
1177 nla_put_failure:
1178 	genlmsg_cancel(skb, ovs_header);
1179 error:
1180 	return -EMSGSIZE;
1181 }
1182 
1183 static struct sk_buff *ovs_dp_cmd_build_info(struct datapath *dp, u32 pid,
1184 					     u32 seq, u8 cmd)
1185 {
1186 	struct sk_buff *skb;
1187 	int retval;
1188 
1189 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1190 	if (!skb)
1191 		return ERR_PTR(-ENOMEM);
1192 
1193 	retval = ovs_dp_cmd_fill_info(dp, skb, pid, seq, 0, cmd);
1194 	if (retval < 0) {
1195 		kfree_skb(skb);
1196 		return ERR_PTR(retval);
1197 	}
1198 	return skb;
1199 }
1200 
1201 /* Called with genl_mutex and optionally with RTNL lock also. */
1202 static struct datapath *lookup_datapath(struct ovs_header *ovs_header,
1203 					struct nlattr *a[OVS_DP_ATTR_MAX + 1])
1204 {
1205 	struct datapath *dp;
1206 
1207 	if (!a[OVS_DP_ATTR_NAME])
1208 		dp = get_dp(ovs_header->dp_ifindex);
1209 	else {
1210 		struct vport *vport;
1211 
1212 		rcu_read_lock();
1213 		vport = ovs_vport_locate(nla_data(a[OVS_DP_ATTR_NAME]));
1214 		dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL;
1215 		rcu_read_unlock();
1216 	}
1217 	return dp ? dp : ERR_PTR(-ENODEV);
1218 }
1219 
1220 static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
1221 {
1222 	struct nlattr **a = info->attrs;
1223 	struct vport_parms parms;
1224 	struct sk_buff *reply;
1225 	struct datapath *dp;
1226 	struct vport *vport;
1227 	int err;
1228 
1229 	err = -EINVAL;
1230 	if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
1231 		goto err;
1232 
1233 	rtnl_lock();
1234 	err = -ENODEV;
1235 	if (!try_module_get(THIS_MODULE))
1236 		goto err_unlock_rtnl;
1237 
1238 	err = -ENOMEM;
1239 	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
1240 	if (dp == NULL)
1241 		goto err_put_module;
1242 	INIT_LIST_HEAD(&dp->port_list);
1243 
1244 	/* Allocate table. */
1245 	err = -ENOMEM;
1246 	rcu_assign_pointer(dp->table, ovs_flow_tbl_alloc(TBL_MIN_BUCKETS));
1247 	if (!dp->table)
1248 		goto err_free_dp;
1249 
1250 	dp->stats_percpu = alloc_percpu(struct dp_stats_percpu);
1251 	if (!dp->stats_percpu) {
1252 		err = -ENOMEM;
1253 		goto err_destroy_table;
1254 	}
1255 
1256 	/* Set up our datapath device. */
1257 	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
1258 	parms.type = OVS_VPORT_TYPE_INTERNAL;
1259 	parms.options = NULL;
1260 	parms.dp = dp;
1261 	parms.port_no = OVSP_LOCAL;
1262 	parms.upcall_pid = nla_get_u32(a[OVS_DP_ATTR_UPCALL_PID]);
1263 
1264 	vport = new_vport(&parms);
1265 	if (IS_ERR(vport)) {
1266 		err = PTR_ERR(vport);
1267 		if (err == -EBUSY)
1268 			err = -EEXIST;
1269 
1270 		goto err_destroy_percpu;
1271 	}
1272 
1273 	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
1274 				      info->snd_seq, OVS_DP_CMD_NEW);
1275 	err = PTR_ERR(reply);
1276 	if (IS_ERR(reply))
1277 		goto err_destroy_local_port;
1278 
1279 	list_add_tail(&dp->list_node, &dps);
1280 	rtnl_unlock();
1281 
1282 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1283 		    ovs_dp_datapath_multicast_group.id, info->nlhdr,
1284 		    GFP_KERNEL);
1285 	return 0;
1286 
1287 err_destroy_local_port:
1288 	ovs_dp_detach_port(rtnl_dereference(dp->ports[OVSP_LOCAL]));
1289 err_destroy_percpu:
1290 	free_percpu(dp->stats_percpu);
1291 err_destroy_table:
1292 	ovs_flow_tbl_destroy(genl_dereference(dp->table));
1293 err_free_dp:
1294 	kfree(dp);
1295 err_put_module:
1296 	module_put(THIS_MODULE);
1297 err_unlock_rtnl:
1298 	rtnl_unlock();
1299 err:
1300 	return err;
1301 }
1302 
1303 static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
1304 {
1305 	struct vport *vport, *next_vport;
1306 	struct sk_buff *reply;
1307 	struct datapath *dp;
1308 	int err;
1309 
1310 	rtnl_lock();
1311 	dp = lookup_datapath(info->userhdr, info->attrs);
1312 	err = PTR_ERR(dp);
1313 	if (IS_ERR(dp))
1314 		goto exit_unlock;
1315 
1316 	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
1317 				      info->snd_seq, OVS_DP_CMD_DEL);
1318 	err = PTR_ERR(reply);
1319 	if (IS_ERR(reply))
1320 		goto exit_unlock;
1321 
1322 	list_for_each_entry_safe(vport, next_vport, &dp->port_list, node)
1323 		if (vport->port_no != OVSP_LOCAL)
1324 			ovs_dp_detach_port(vport);
1325 
1326 	list_del(&dp->list_node);
1327 	ovs_dp_detach_port(rtnl_dereference(dp->ports[OVSP_LOCAL]));
1328 
1329 	/* rtnl_unlock() will wait until all the references to devices that
1330 	 * are pending unregistration have been dropped.  We do it here to
1331 	 * ensure that any internal devices (which contain DP pointers) are
1332 	 * fully destroyed before freeing the datapath.
1333 	 */
1334 	rtnl_unlock();
1335 
1336 	call_rcu(&dp->rcu, destroy_dp_rcu);
1337 	module_put(THIS_MODULE);
1338 
1339 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1340 		    ovs_dp_datapath_multicast_group.id, info->nlhdr,
1341 		    GFP_KERNEL);
1342 
1343 	return 0;
1344 
1345 exit_unlock:
1346 	rtnl_unlock();
1347 	return err;
1348 }
1349 
1350 static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
1351 {
1352 	struct sk_buff *reply;
1353 	struct datapath *dp;
1354 	int err;
1355 
1356 	dp = lookup_datapath(info->userhdr, info->attrs);
1357 	if (IS_ERR(dp))
1358 		return PTR_ERR(dp);
1359 
1360 	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
1361 				      info->snd_seq, OVS_DP_CMD_NEW);
1362 	if (IS_ERR(reply)) {
1363 		err = PTR_ERR(reply);
1364 		netlink_set_err(init_net.genl_sock, 0,
1365 				ovs_dp_datapath_multicast_group.id, err);
1366 		return 0;
1367 	}
1368 
1369 	genl_notify(reply, genl_info_net(info), info->snd_pid,
1370 		    ovs_dp_datapath_multicast_group.id, info->nlhdr,
1371 		    GFP_KERNEL);
1372 
1373 	return 0;
1374 }
1375 
1376 static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
1377 {
1378 	struct sk_buff *reply;
1379 	struct datapath *dp;
1380 
1381 	dp = lookup_datapath(info->userhdr, info->attrs);
1382 	if (IS_ERR(dp))
1383 		return PTR_ERR(dp);
1384 
1385 	reply = ovs_dp_cmd_build_info(dp, info->snd_pid,
1386 				      info->snd_seq, OVS_DP_CMD_NEW);
1387 	if (IS_ERR(reply))
1388 		return PTR_ERR(reply);
1389 
1390 	return genlmsg_reply(reply, info);
1391 }
1392 
1393 static int ovs_dp_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1394 {
1395 	struct datapath *dp;
1396 	int skip = cb->args[0];
1397 	int i = 0;
1398 
1399 	list_for_each_entry(dp, &dps, list_node) {
1400 		if (i < skip)
1401 			continue;
1402 		if (ovs_dp_cmd_fill_info(dp, skb, NETLINK_CB(cb->skb).pid,
1403 					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1404 					 OVS_DP_CMD_NEW) < 0)
1405 			break;
1406 		i++;
1407 	}
1408 
1409 	cb->args[0] = i;
1410 
1411 	return skb->len;
1412 }
1413 
1414 static struct genl_ops dp_datapath_genl_ops[] = {
1415 	{ .cmd = OVS_DP_CMD_NEW,
1416 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1417 	  .policy = datapath_policy,
1418 	  .doit = ovs_dp_cmd_new
1419 	},
1420 	{ .cmd = OVS_DP_CMD_DEL,
1421 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1422 	  .policy = datapath_policy,
1423 	  .doit = ovs_dp_cmd_del
1424 	},
1425 	{ .cmd = OVS_DP_CMD_GET,
1426 	  .flags = 0,		    /* OK for unprivileged users. */
1427 	  .policy = datapath_policy,
1428 	  .doit = ovs_dp_cmd_get,
1429 	  .dumpit = ovs_dp_cmd_dump
1430 	},
1431 	{ .cmd = OVS_DP_CMD_SET,
1432 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1433 	  .policy = datapath_policy,
1434 	  .doit = ovs_dp_cmd_set,
1435 	},
1436 };
1437 
1438 static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
1439 	[OVS_VPORT_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1440 	[OVS_VPORT_ATTR_STATS] = { .len = sizeof(struct ovs_vport_stats) },
1441 	[OVS_VPORT_ATTR_PORT_NO] = { .type = NLA_U32 },
1442 	[OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 },
1443 	[OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1444 	[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
1445 };
1446 
1447 static struct genl_family dp_vport_genl_family = {
1448 	.id = GENL_ID_GENERATE,
1449 	.hdrsize = sizeof(struct ovs_header),
1450 	.name = OVS_VPORT_FAMILY,
1451 	.version = OVS_VPORT_VERSION,
1452 	.maxattr = OVS_VPORT_ATTR_MAX
1453 };
1454 
1455 struct genl_multicast_group ovs_dp_vport_multicast_group = {
1456 	.name = OVS_VPORT_MCGROUP
1457 };
1458 
1459 /* Called with RTNL lock or RCU read lock. */
1460 static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
1461 				   u32 pid, u32 seq, u32 flags, u8 cmd)
1462 {
1463 	struct ovs_header *ovs_header;
1464 	struct ovs_vport_stats vport_stats;
1465 	int err;
1466 
1467 	ovs_header = genlmsg_put(skb, pid, seq, &dp_vport_genl_family,
1468 				 flags, cmd);
1469 	if (!ovs_header)
1470 		return -EMSGSIZE;
1471 
1472 	ovs_header->dp_ifindex = get_dpifindex(vport->dp);
1473 
1474 	NLA_PUT_U32(skb, OVS_VPORT_ATTR_PORT_NO, vport->port_no);
1475 	NLA_PUT_U32(skb, OVS_VPORT_ATTR_TYPE, vport->ops->type);
1476 	NLA_PUT_STRING(skb, OVS_VPORT_ATTR_NAME, vport->ops->get_name(vport));
1477 	NLA_PUT_U32(skb, OVS_VPORT_ATTR_UPCALL_PID, vport->upcall_pid);
1478 
1479 	ovs_vport_get_stats(vport, &vport_stats);
1480 	NLA_PUT(skb, OVS_VPORT_ATTR_STATS, sizeof(struct ovs_vport_stats),
1481 		&vport_stats);
1482 
1483 	err = ovs_vport_get_options(vport, skb);
1484 	if (err == -EMSGSIZE)
1485 		goto error;
1486 
1487 	return genlmsg_end(skb, ovs_header);
1488 
1489 nla_put_failure:
1490 	err = -EMSGSIZE;
1491 error:
1492 	genlmsg_cancel(skb, ovs_header);
1493 	return err;
1494 }
1495 
1496 /* Called with RTNL lock or RCU read lock. */
1497 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, u32 pid,
1498 					 u32 seq, u8 cmd)
1499 {
1500 	struct sk_buff *skb;
1501 	int retval;
1502 
1503 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1504 	if (!skb)
1505 		return ERR_PTR(-ENOMEM);
1506 
1507 	retval = ovs_vport_cmd_fill_info(vport, skb, pid, seq, 0, cmd);
1508 	if (retval < 0) {
1509 		kfree_skb(skb);
1510 		return ERR_PTR(retval);
1511 	}
1512 	return skb;
1513 }
1514 
1515 /* Called with RTNL lock or RCU read lock. */
1516 static struct vport *lookup_vport(struct ovs_header *ovs_header,
1517 				  struct nlattr *a[OVS_VPORT_ATTR_MAX + 1])
1518 {
1519 	struct datapath *dp;
1520 	struct vport *vport;
1521 
1522 	if (a[OVS_VPORT_ATTR_NAME]) {
1523 		vport = ovs_vport_locate(nla_data(a[OVS_VPORT_ATTR_NAME]));
1524 		if (!vport)
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