xref: /openbmc/linux/net/openvswitch/datapath.c (revision 6774def6)
1 /*
2  * Copyright (c) 2007-2014 Nicira, Inc.
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 <net/genetlink.h>
51 #include <net/net_namespace.h>
52 #include <net/netns/generic.h>
53 
54 #include "datapath.h"
55 #include "flow.h"
56 #include "flow_table.h"
57 #include "flow_netlink.h"
58 #include "vport-internal_dev.h"
59 #include "vport-netdev.h"
60 
61 int ovs_net_id __read_mostly;
62 
63 static struct genl_family dp_packet_genl_family;
64 static struct genl_family dp_flow_genl_family;
65 static struct genl_family dp_datapath_genl_family;
66 
67 static const struct genl_multicast_group ovs_dp_flow_multicast_group = {
68 	.name = OVS_FLOW_MCGROUP,
69 };
70 
71 static const struct genl_multicast_group ovs_dp_datapath_multicast_group = {
72 	.name = OVS_DATAPATH_MCGROUP,
73 };
74 
75 static const struct genl_multicast_group ovs_dp_vport_multicast_group = {
76 	.name = OVS_VPORT_MCGROUP,
77 };
78 
79 /* Check if need to build a reply message.
80  * OVS userspace sets the NLM_F_ECHO flag if it needs the reply. */
81 static bool ovs_must_notify(struct genl_family *family, struct genl_info *info,
82 			    unsigned int group)
83 {
84 	return info->nlhdr->nlmsg_flags & NLM_F_ECHO ||
85 	       genl_has_listeners(family, genl_info_net(info)->genl_sock,
86 				  group);
87 }
88 
89 static void ovs_notify(struct genl_family *family,
90 		       struct sk_buff *skb, struct genl_info *info)
91 {
92 	genl_notify(family, skb, genl_info_net(info), info->snd_portid,
93 		    0, info->nlhdr, GFP_KERNEL);
94 }
95 
96 /**
97  * DOC: Locking:
98  *
99  * All writes e.g. Writes to device state (add/remove datapath, port, set
100  * operations on vports, etc.), Writes to other state (flow table
101  * modifications, set miscellaneous datapath parameters, etc.) are protected
102  * by ovs_lock.
103  *
104  * Reads are protected by RCU.
105  *
106  * There are a few special cases (mostly stats) that have their own
107  * synchronization but they nest under all of above and don't interact with
108  * each other.
109  *
110  * The RTNL lock nests inside ovs_mutex.
111  */
112 
113 static DEFINE_MUTEX(ovs_mutex);
114 
115 void ovs_lock(void)
116 {
117 	mutex_lock(&ovs_mutex);
118 }
119 
120 void ovs_unlock(void)
121 {
122 	mutex_unlock(&ovs_mutex);
123 }
124 
125 #ifdef CONFIG_LOCKDEP
126 int lockdep_ovsl_is_held(void)
127 {
128 	if (debug_locks)
129 		return lockdep_is_held(&ovs_mutex);
130 	else
131 		return 1;
132 }
133 #endif
134 
135 static struct vport *new_vport(const struct vport_parms *);
136 static int queue_gso_packets(struct datapath *dp, struct sk_buff *,
137 			     const struct dp_upcall_info *);
138 static int queue_userspace_packet(struct datapath *dp, struct sk_buff *,
139 				  const struct dp_upcall_info *);
140 
141 /* Must be called with rcu_read_lock or ovs_mutex. */
142 static struct datapath *get_dp(struct net *net, int dp_ifindex)
143 {
144 	struct datapath *dp = NULL;
145 	struct net_device *dev;
146 
147 	rcu_read_lock();
148 	dev = dev_get_by_index_rcu(net, dp_ifindex);
149 	if (dev) {
150 		struct vport *vport = ovs_internal_dev_get_vport(dev);
151 		if (vport)
152 			dp = vport->dp;
153 	}
154 	rcu_read_unlock();
155 
156 	return dp;
157 }
158 
159 /* Must be called with rcu_read_lock or ovs_mutex. */
160 const char *ovs_dp_name(const struct datapath *dp)
161 {
162 	struct vport *vport = ovs_vport_ovsl_rcu(dp, OVSP_LOCAL);
163 	return vport->ops->get_name(vport);
164 }
165 
166 static int get_dpifindex(struct datapath *dp)
167 {
168 	struct vport *local;
169 	int ifindex;
170 
171 	rcu_read_lock();
172 
173 	local = ovs_vport_rcu(dp, OVSP_LOCAL);
174 	if (local)
175 		ifindex = netdev_vport_priv(local)->dev->ifindex;
176 	else
177 		ifindex = 0;
178 
179 	rcu_read_unlock();
180 
181 	return ifindex;
182 }
183 
184 static void destroy_dp_rcu(struct rcu_head *rcu)
185 {
186 	struct datapath *dp = container_of(rcu, struct datapath, rcu);
187 
188 	free_percpu(dp->stats_percpu);
189 	release_net(ovs_dp_get_net(dp));
190 	kfree(dp->ports);
191 	kfree(dp);
192 }
193 
194 static struct hlist_head *vport_hash_bucket(const struct datapath *dp,
195 					    u16 port_no)
196 {
197 	return &dp->ports[port_no & (DP_VPORT_HASH_BUCKETS - 1)];
198 }
199 
200 /* Called with ovs_mutex or RCU read lock. */
201 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no)
202 {
203 	struct vport *vport;
204 	struct hlist_head *head;
205 
206 	head = vport_hash_bucket(dp, port_no);
207 	hlist_for_each_entry_rcu(vport, head, dp_hash_node) {
208 		if (vport->port_no == port_no)
209 			return vport;
210 	}
211 	return NULL;
212 }
213 
214 /* Called with ovs_mutex. */
215 static struct vport *new_vport(const struct vport_parms *parms)
216 {
217 	struct vport *vport;
218 
219 	vport = ovs_vport_add(parms);
220 	if (!IS_ERR(vport)) {
221 		struct datapath *dp = parms->dp;
222 		struct hlist_head *head = vport_hash_bucket(dp, vport->port_no);
223 
224 		hlist_add_head_rcu(&vport->dp_hash_node, head);
225 	}
226 	return vport;
227 }
228 
229 void ovs_dp_detach_port(struct vport *p)
230 {
231 	ASSERT_OVSL();
232 
233 	/* First drop references to device. */
234 	hlist_del_rcu(&p->dp_hash_node);
235 
236 	/* Then destroy it. */
237 	ovs_vport_del(p);
238 }
239 
240 /* Must be called with rcu_read_lock. */
241 void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key)
242 {
243 	const struct vport *p = OVS_CB(skb)->input_vport;
244 	struct datapath *dp = p->dp;
245 	struct sw_flow *flow;
246 	struct dp_stats_percpu *stats;
247 	u64 *stats_counter;
248 	u32 n_mask_hit;
249 
250 	stats = this_cpu_ptr(dp->stats_percpu);
251 
252 	/* Look up flow. */
253 	flow = ovs_flow_tbl_lookup_stats(&dp->table, key, &n_mask_hit);
254 	if (unlikely(!flow)) {
255 		struct dp_upcall_info upcall;
256 		int error;
257 
258 		upcall.cmd = OVS_PACKET_CMD_MISS;
259 		upcall.key = key;
260 		upcall.userdata = NULL;
261 		upcall.portid = ovs_vport_find_upcall_portid(p, skb);
262 		error = ovs_dp_upcall(dp, skb, &upcall);
263 		if (unlikely(error))
264 			kfree_skb(skb);
265 		else
266 			consume_skb(skb);
267 		stats_counter = &stats->n_missed;
268 		goto out;
269 	}
270 
271 	OVS_CB(skb)->flow = flow;
272 
273 	ovs_flow_stats_update(OVS_CB(skb)->flow, key->tp.flags, skb);
274 	ovs_execute_actions(dp, skb, key);
275 	stats_counter = &stats->n_hit;
276 
277 out:
278 	/* Update datapath statistics. */
279 	u64_stats_update_begin(&stats->syncp);
280 	(*stats_counter)++;
281 	stats->n_mask_hit += n_mask_hit;
282 	u64_stats_update_end(&stats->syncp);
283 }
284 
285 int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
286 		  const struct dp_upcall_info *upcall_info)
287 {
288 	struct dp_stats_percpu *stats;
289 	int err;
290 
291 	if (upcall_info->portid == 0) {
292 		err = -ENOTCONN;
293 		goto err;
294 	}
295 
296 	if (!skb_is_gso(skb))
297 		err = queue_userspace_packet(dp, skb, upcall_info);
298 	else
299 		err = queue_gso_packets(dp, skb, upcall_info);
300 	if (err)
301 		goto err;
302 
303 	return 0;
304 
305 err:
306 	stats = this_cpu_ptr(dp->stats_percpu);
307 
308 	u64_stats_update_begin(&stats->syncp);
309 	stats->n_lost++;
310 	u64_stats_update_end(&stats->syncp);
311 
312 	return err;
313 }
314 
315 static int queue_gso_packets(struct datapath *dp, struct sk_buff *skb,
316 			     const struct dp_upcall_info *upcall_info)
317 {
318 	unsigned short gso_type = skb_shinfo(skb)->gso_type;
319 	struct dp_upcall_info later_info;
320 	struct sw_flow_key later_key;
321 	struct sk_buff *segs, *nskb;
322 	int err;
323 
324 	segs = __skb_gso_segment(skb, NETIF_F_SG, false);
325 	if (IS_ERR(segs))
326 		return PTR_ERR(segs);
327 	if (segs == NULL)
328 		return -EINVAL;
329 
330 	/* Queue all of the segments. */
331 	skb = segs;
332 	do {
333 		err = queue_userspace_packet(dp, skb, upcall_info);
334 		if (err)
335 			break;
336 
337 		if (skb == segs && gso_type & SKB_GSO_UDP) {
338 			/* The initial flow key extracted by ovs_flow_extract()
339 			 * in this case is for a first fragment, so we need to
340 			 * properly mark later fragments.
341 			 */
342 			later_key = *upcall_info->key;
343 			later_key.ip.frag = OVS_FRAG_TYPE_LATER;
344 
345 			later_info = *upcall_info;
346 			later_info.key = &later_key;
347 			upcall_info = &later_info;
348 		}
349 	} while ((skb = skb->next));
350 
351 	/* Free all of the segments. */
352 	skb = segs;
353 	do {
354 		nskb = skb->next;
355 		if (err)
356 			kfree_skb(skb);
357 		else
358 			consume_skb(skb);
359 	} while ((skb = nskb));
360 	return err;
361 }
362 
363 static size_t key_attr_size(void)
364 {
365 	return    nla_total_size(4)   /* OVS_KEY_ATTR_PRIORITY */
366 		+ nla_total_size(0)   /* OVS_KEY_ATTR_TUNNEL */
367 		  + nla_total_size(8)   /* OVS_TUNNEL_KEY_ATTR_ID */
368 		  + nla_total_size(4)   /* OVS_TUNNEL_KEY_ATTR_IPV4_SRC */
369 		  + nla_total_size(4)   /* OVS_TUNNEL_KEY_ATTR_IPV4_DST */
370 		  + nla_total_size(1)   /* OVS_TUNNEL_KEY_ATTR_TOS */
371 		  + nla_total_size(1)   /* OVS_TUNNEL_KEY_ATTR_TTL */
372 		  + nla_total_size(0)   /* OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT */
373 		  + nla_total_size(0)   /* OVS_TUNNEL_KEY_ATTR_CSUM */
374 		  + nla_total_size(0)   /* OVS_TUNNEL_KEY_ATTR_OAM */
375 		  + nla_total_size(256)   /* OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS */
376 		+ nla_total_size(4)   /* OVS_KEY_ATTR_IN_PORT */
377 		+ nla_total_size(4)   /* OVS_KEY_ATTR_SKB_MARK */
378 		+ nla_total_size(12)  /* OVS_KEY_ATTR_ETHERNET */
379 		+ nla_total_size(2)   /* OVS_KEY_ATTR_ETHERTYPE */
380 		+ nla_total_size(4)   /* OVS_KEY_ATTR_8021Q */
381 		+ nla_total_size(0)   /* OVS_KEY_ATTR_ENCAP */
382 		+ nla_total_size(2)   /* OVS_KEY_ATTR_ETHERTYPE */
383 		+ nla_total_size(40)  /* OVS_KEY_ATTR_IPV6 */
384 		+ nla_total_size(2)   /* OVS_KEY_ATTR_ICMPV6 */
385 		+ nla_total_size(28); /* OVS_KEY_ATTR_ND */
386 }
387 
388 static size_t upcall_msg_size(const struct nlattr *userdata,
389 			      unsigned int hdrlen)
390 {
391 	size_t size = NLMSG_ALIGN(sizeof(struct ovs_header))
392 		+ nla_total_size(hdrlen) /* OVS_PACKET_ATTR_PACKET */
393 		+ nla_total_size(key_attr_size()); /* OVS_PACKET_ATTR_KEY */
394 
395 	/* OVS_PACKET_ATTR_USERDATA */
396 	if (userdata)
397 		size += NLA_ALIGN(userdata->nla_len);
398 
399 	return size;
400 }
401 
402 static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
403 				  const struct dp_upcall_info *upcall_info)
404 {
405 	struct ovs_header *upcall;
406 	struct sk_buff *nskb = NULL;
407 	struct sk_buff *user_skb = NULL; /* to be queued to userspace */
408 	struct nlattr *nla;
409 	struct genl_info info = {
410 		.dst_sk = ovs_dp_get_net(dp)->genl_sock,
411 		.snd_portid = upcall_info->portid,
412 	};
413 	size_t len;
414 	unsigned int hlen;
415 	int err, dp_ifindex;
416 
417 	dp_ifindex = get_dpifindex(dp);
418 	if (!dp_ifindex)
419 		return -ENODEV;
420 
421 	if (vlan_tx_tag_present(skb)) {
422 		nskb = skb_clone(skb, GFP_ATOMIC);
423 		if (!nskb)
424 			return -ENOMEM;
425 
426 		nskb = __vlan_put_tag(nskb, nskb->vlan_proto, vlan_tx_tag_get(nskb));
427 		if (!nskb)
428 			return -ENOMEM;
429 
430 		nskb->vlan_tci = 0;
431 		skb = nskb;
432 	}
433 
434 	if (nla_attr_size(skb->len) > USHRT_MAX) {
435 		err = -EFBIG;
436 		goto out;
437 	}
438 
439 	/* Complete checksum if needed */
440 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
441 	    (err = skb_checksum_help(skb)))
442 		goto out;
443 
444 	/* Older versions of OVS user space enforce alignment of the last
445 	 * Netlink attribute to NLA_ALIGNTO which would require extensive
446 	 * padding logic. Only perform zerocopy if padding is not required.
447 	 */
448 	if (dp->user_features & OVS_DP_F_UNALIGNED)
449 		hlen = skb_zerocopy_headlen(skb);
450 	else
451 		hlen = skb->len;
452 
453 	len = upcall_msg_size(upcall_info->userdata, hlen);
454 	user_skb = genlmsg_new_unicast(len, &info, GFP_ATOMIC);
455 	if (!user_skb) {
456 		err = -ENOMEM;
457 		goto out;
458 	}
459 
460 	upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
461 			     0, upcall_info->cmd);
462 	upcall->dp_ifindex = dp_ifindex;
463 
464 	nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_KEY);
465 	err = ovs_nla_put_flow(upcall_info->key, upcall_info->key, user_skb);
466 	BUG_ON(err);
467 	nla_nest_end(user_skb, nla);
468 
469 	if (upcall_info->userdata)
470 		__nla_put(user_skb, OVS_PACKET_ATTR_USERDATA,
471 			  nla_len(upcall_info->userdata),
472 			  nla_data(upcall_info->userdata));
473 
474 	/* Only reserve room for attribute header, packet data is added
475 	 * in skb_zerocopy() */
476 	if (!(nla = nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, 0))) {
477 		err = -ENOBUFS;
478 		goto out;
479 	}
480 	nla->nla_len = nla_attr_size(skb->len);
481 
482 	err = skb_zerocopy(user_skb, skb, skb->len, hlen);
483 	if (err)
484 		goto out;
485 
486 	/* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */
487 	if (!(dp->user_features & OVS_DP_F_UNALIGNED)) {
488 		size_t plen = NLA_ALIGN(user_skb->len) - user_skb->len;
489 
490 		if (plen > 0)
491 			memset(skb_put(user_skb, plen), 0, plen);
492 	}
493 
494 	((struct nlmsghdr *) user_skb->data)->nlmsg_len = user_skb->len;
495 
496 	err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
497 	user_skb = NULL;
498 out:
499 	if (err)
500 		skb_tx_error(skb);
501 	kfree_skb(user_skb);
502 	kfree_skb(nskb);
503 	return err;
504 }
505 
506 static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
507 {
508 	struct ovs_header *ovs_header = info->userhdr;
509 	struct nlattr **a = info->attrs;
510 	struct sw_flow_actions *acts;
511 	struct sk_buff *packet;
512 	struct sw_flow *flow;
513 	struct datapath *dp;
514 	struct ethhdr *eth;
515 	struct vport *input_vport;
516 	int len;
517 	int err;
518 
519 	err = -EINVAL;
520 	if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] ||
521 	    !a[OVS_PACKET_ATTR_ACTIONS])
522 		goto err;
523 
524 	len = nla_len(a[OVS_PACKET_ATTR_PACKET]);
525 	packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL);
526 	err = -ENOMEM;
527 	if (!packet)
528 		goto err;
529 	skb_reserve(packet, NET_IP_ALIGN);
530 
531 	nla_memcpy(__skb_put(packet, len), a[OVS_PACKET_ATTR_PACKET], len);
532 
533 	skb_reset_mac_header(packet);
534 	eth = eth_hdr(packet);
535 
536 	/* Normally, setting the skb 'protocol' field would be handled by a
537 	 * call to eth_type_trans(), but it assumes there's a sending
538 	 * device, which we may not have. */
539 	if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN)
540 		packet->protocol = eth->h_proto;
541 	else
542 		packet->protocol = htons(ETH_P_802_2);
543 
544 	/* Build an sw_flow for sending this packet. */
545 	flow = ovs_flow_alloc();
546 	err = PTR_ERR(flow);
547 	if (IS_ERR(flow))
548 		goto err_kfree_skb;
549 
550 	err = ovs_flow_key_extract_userspace(a[OVS_PACKET_ATTR_KEY], packet,
551 					     &flow->key);
552 	if (err)
553 		goto err_flow_free;
554 
555 	acts = ovs_nla_alloc_flow_actions(nla_len(a[OVS_PACKET_ATTR_ACTIONS]));
556 	err = PTR_ERR(acts);
557 	if (IS_ERR(acts))
558 		goto err_flow_free;
559 
560 	err = ovs_nla_copy_actions(a[OVS_PACKET_ATTR_ACTIONS],
561 				   &flow->key, 0, &acts);
562 	if (err)
563 		goto err_flow_free;
564 
565 	rcu_assign_pointer(flow->sf_acts, acts);
566 
567 	OVS_CB(packet)->egress_tun_info = NULL;
568 	OVS_CB(packet)->flow = flow;
569 	packet->priority = flow->key.phy.priority;
570 	packet->mark = flow->key.phy.skb_mark;
571 
572 	rcu_read_lock();
573 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
574 	err = -ENODEV;
575 	if (!dp)
576 		goto err_unlock;
577 
578 	input_vport = ovs_vport_rcu(dp, flow->key.phy.in_port);
579 	if (!input_vport)
580 		input_vport = ovs_vport_rcu(dp, OVSP_LOCAL);
581 
582 	if (!input_vport)
583 		goto err_unlock;
584 
585 	OVS_CB(packet)->input_vport = input_vport;
586 
587 	local_bh_disable();
588 	err = ovs_execute_actions(dp, packet, &flow->key);
589 	local_bh_enable();
590 	rcu_read_unlock();
591 
592 	ovs_flow_free(flow, false);
593 	return err;
594 
595 err_unlock:
596 	rcu_read_unlock();
597 err_flow_free:
598 	ovs_flow_free(flow, false);
599 err_kfree_skb:
600 	kfree_skb(packet);
601 err:
602 	return err;
603 }
604 
605 static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = {
606 	[OVS_PACKET_ATTR_PACKET] = { .len = ETH_HLEN },
607 	[OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED },
608 	[OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED },
609 };
610 
611 static const struct genl_ops dp_packet_genl_ops[] = {
612 	{ .cmd = OVS_PACKET_CMD_EXECUTE,
613 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
614 	  .policy = packet_policy,
615 	  .doit = ovs_packet_cmd_execute
616 	}
617 };
618 
619 static struct genl_family dp_packet_genl_family = {
620 	.id = GENL_ID_GENERATE,
621 	.hdrsize = sizeof(struct ovs_header),
622 	.name = OVS_PACKET_FAMILY,
623 	.version = OVS_PACKET_VERSION,
624 	.maxattr = OVS_PACKET_ATTR_MAX,
625 	.netnsok = true,
626 	.parallel_ops = true,
627 	.ops = dp_packet_genl_ops,
628 	.n_ops = ARRAY_SIZE(dp_packet_genl_ops),
629 };
630 
631 static void get_dp_stats(struct datapath *dp, struct ovs_dp_stats *stats,
632 			 struct ovs_dp_megaflow_stats *mega_stats)
633 {
634 	int i;
635 
636 	memset(mega_stats, 0, sizeof(*mega_stats));
637 
638 	stats->n_flows = ovs_flow_tbl_count(&dp->table);
639 	mega_stats->n_masks = ovs_flow_tbl_num_masks(&dp->table);
640 
641 	stats->n_hit = stats->n_missed = stats->n_lost = 0;
642 
643 	for_each_possible_cpu(i) {
644 		const struct dp_stats_percpu *percpu_stats;
645 		struct dp_stats_percpu local_stats;
646 		unsigned int start;
647 
648 		percpu_stats = per_cpu_ptr(dp->stats_percpu, i);
649 
650 		do {
651 			start = u64_stats_fetch_begin_irq(&percpu_stats->syncp);
652 			local_stats = *percpu_stats;
653 		} while (u64_stats_fetch_retry_irq(&percpu_stats->syncp, start));
654 
655 		stats->n_hit += local_stats.n_hit;
656 		stats->n_missed += local_stats.n_missed;
657 		stats->n_lost += local_stats.n_lost;
658 		mega_stats->n_mask_hit += local_stats.n_mask_hit;
659 	}
660 }
661 
662 static size_t ovs_flow_cmd_msg_size(const struct sw_flow_actions *acts)
663 {
664 	return NLMSG_ALIGN(sizeof(struct ovs_header))
665 		+ nla_total_size(key_attr_size()) /* OVS_FLOW_ATTR_KEY */
666 		+ nla_total_size(key_attr_size()) /* OVS_FLOW_ATTR_MASK */
667 		+ nla_total_size(sizeof(struct ovs_flow_stats)) /* OVS_FLOW_ATTR_STATS */
668 		+ nla_total_size(1) /* OVS_FLOW_ATTR_TCP_FLAGS */
669 		+ nla_total_size(8) /* OVS_FLOW_ATTR_USED */
670 		+ nla_total_size(acts->actions_len); /* OVS_FLOW_ATTR_ACTIONS */
671 }
672 
673 /* Called with ovs_mutex or RCU read lock. */
674 static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
675 				  struct sk_buff *skb, u32 portid,
676 				  u32 seq, u32 flags, u8 cmd)
677 {
678 	const int skb_orig_len = skb->len;
679 	struct nlattr *start;
680 	struct ovs_flow_stats stats;
681 	__be16 tcp_flags;
682 	unsigned long used;
683 	struct ovs_header *ovs_header;
684 	struct nlattr *nla;
685 	int err;
686 
687 	ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family, flags, cmd);
688 	if (!ovs_header)
689 		return -EMSGSIZE;
690 
691 	ovs_header->dp_ifindex = dp_ifindex;
692 
693 	/* Fill flow key. */
694 	nla = nla_nest_start(skb, OVS_FLOW_ATTR_KEY);
695 	if (!nla)
696 		goto nla_put_failure;
697 
698 	err = ovs_nla_put_flow(&flow->unmasked_key, &flow->unmasked_key, skb);
699 	if (err)
700 		goto error;
701 	nla_nest_end(skb, nla);
702 
703 	nla = nla_nest_start(skb, OVS_FLOW_ATTR_MASK);
704 	if (!nla)
705 		goto nla_put_failure;
706 
707 	err = ovs_nla_put_flow(&flow->key, &flow->mask->key, skb);
708 	if (err)
709 		goto error;
710 
711 	nla_nest_end(skb, nla);
712 
713 	ovs_flow_stats_get(flow, &stats, &used, &tcp_flags);
714 
715 	if (used &&
716 	    nla_put_u64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used)))
717 		goto nla_put_failure;
718 
719 	if (stats.n_packets &&
720 	    nla_put(skb, OVS_FLOW_ATTR_STATS, sizeof(struct ovs_flow_stats), &stats))
721 		goto nla_put_failure;
722 
723 	if ((u8)ntohs(tcp_flags) &&
724 	     nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags)))
725 		goto nla_put_failure;
726 
727 	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
728 	 * this is the first flow to be dumped into 'skb'.  This is unusual for
729 	 * Netlink but individual action lists can be longer than
730 	 * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this.
731 	 * The userspace caller can always fetch the actions separately if it
732 	 * really wants them.  (Most userspace callers in fact don't care.)
733 	 *
734 	 * This can only fail for dump operations because the skb is always
735 	 * properly sized for single flows.
736 	 */
737 	start = nla_nest_start(skb, OVS_FLOW_ATTR_ACTIONS);
738 	if (start) {
739 		const struct sw_flow_actions *sf_acts;
740 
741 		sf_acts = rcu_dereference_ovsl(flow->sf_acts);
742 		err = ovs_nla_put_actions(sf_acts->actions,
743 					  sf_acts->actions_len, skb);
744 
745 		if (!err)
746 			nla_nest_end(skb, start);
747 		else {
748 			if (skb_orig_len)
749 				goto error;
750 
751 			nla_nest_cancel(skb, start);
752 		}
753 	} else if (skb_orig_len)
754 		goto nla_put_failure;
755 
756 	return genlmsg_end(skb, ovs_header);
757 
758 nla_put_failure:
759 	err = -EMSGSIZE;
760 error:
761 	genlmsg_cancel(skb, ovs_header);
762 	return err;
763 }
764 
765 /* May not be called with RCU read lock. */
766 static struct sk_buff *ovs_flow_cmd_alloc_info(const struct sw_flow_actions *acts,
767 					       struct genl_info *info,
768 					       bool always)
769 {
770 	struct sk_buff *skb;
771 
772 	if (!always && !ovs_must_notify(&dp_flow_genl_family, info, 0))
773 		return NULL;
774 
775 	skb = genlmsg_new_unicast(ovs_flow_cmd_msg_size(acts), info, GFP_KERNEL);
776 	if (!skb)
777 		return ERR_PTR(-ENOMEM);
778 
779 	return skb;
780 }
781 
782 /* Called with ovs_mutex. */
783 static struct sk_buff *ovs_flow_cmd_build_info(const struct sw_flow *flow,
784 					       int dp_ifindex,
785 					       struct genl_info *info, u8 cmd,
786 					       bool always)
787 {
788 	struct sk_buff *skb;
789 	int retval;
790 
791 	skb = ovs_flow_cmd_alloc_info(ovsl_dereference(flow->sf_acts), info,
792 				      always);
793 	if (IS_ERR_OR_NULL(skb))
794 		return skb;
795 
796 	retval = ovs_flow_cmd_fill_info(flow, dp_ifindex, skb,
797 					info->snd_portid, info->snd_seq, 0,
798 					cmd);
799 	BUG_ON(retval < 0);
800 	return skb;
801 }
802 
803 static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
804 {
805 	struct nlattr **a = info->attrs;
806 	struct ovs_header *ovs_header = info->userhdr;
807 	struct sw_flow *flow, *new_flow;
808 	struct sw_flow_mask mask;
809 	struct sk_buff *reply;
810 	struct datapath *dp;
811 	struct sw_flow_actions *acts;
812 	struct sw_flow_match match;
813 	int error;
814 
815 	/* Must have key and actions. */
816 	error = -EINVAL;
817 	if (!a[OVS_FLOW_ATTR_KEY])
818 		goto error;
819 	if (!a[OVS_FLOW_ATTR_ACTIONS])
820 		goto error;
821 
822 	/* Most of the time we need to allocate a new flow, do it before
823 	 * locking.
824 	 */
825 	new_flow = ovs_flow_alloc();
826 	if (IS_ERR(new_flow)) {
827 		error = PTR_ERR(new_flow);
828 		goto error;
829 	}
830 
831 	/* Extract key. */
832 	ovs_match_init(&match, &new_flow->unmasked_key, &mask);
833 	error = ovs_nla_get_match(&match,
834 				  a[OVS_FLOW_ATTR_KEY], a[OVS_FLOW_ATTR_MASK]);
835 	if (error)
836 		goto err_kfree_flow;
837 
838 	ovs_flow_mask_key(&new_flow->key, &new_flow->unmasked_key, &mask);
839 
840 	/* Validate actions. */
841 	acts = ovs_nla_alloc_flow_actions(nla_len(a[OVS_FLOW_ATTR_ACTIONS]));
842 	error = PTR_ERR(acts);
843 	if (IS_ERR(acts))
844 		goto err_kfree_flow;
845 
846 	error = ovs_nla_copy_actions(a[OVS_FLOW_ATTR_ACTIONS], &new_flow->key,
847 				     0, &acts);
848 	if (error) {
849 		OVS_NLERR("Flow actions may not be safe on all matching packets.\n");
850 		goto err_kfree_acts;
851 	}
852 
853 	reply = ovs_flow_cmd_alloc_info(acts, info, false);
854 	if (IS_ERR(reply)) {
855 		error = PTR_ERR(reply);
856 		goto err_kfree_acts;
857 	}
858 
859 	ovs_lock();
860 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
861 	if (unlikely(!dp)) {
862 		error = -ENODEV;
863 		goto err_unlock_ovs;
864 	}
865 	/* Check if this is a duplicate flow */
866 	flow = ovs_flow_tbl_lookup(&dp->table, &new_flow->unmasked_key);
867 	if (likely(!flow)) {
868 		rcu_assign_pointer(new_flow->sf_acts, acts);
869 
870 		/* Put flow in bucket. */
871 		error = ovs_flow_tbl_insert(&dp->table, new_flow, &mask);
872 		if (unlikely(error)) {
873 			acts = NULL;
874 			goto err_unlock_ovs;
875 		}
876 
877 		if (unlikely(reply)) {
878 			error = ovs_flow_cmd_fill_info(new_flow,
879 						       ovs_header->dp_ifindex,
880 						       reply, info->snd_portid,
881 						       info->snd_seq, 0,
882 						       OVS_FLOW_CMD_NEW);
883 			BUG_ON(error < 0);
884 		}
885 		ovs_unlock();
886 	} else {
887 		struct sw_flow_actions *old_acts;
888 
889 		/* Bail out if we're not allowed to modify an existing flow.
890 		 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
891 		 * because Generic Netlink treats the latter as a dump
892 		 * request.  We also accept NLM_F_EXCL in case that bug ever
893 		 * gets fixed.
894 		 */
895 		if (unlikely(info->nlhdr->nlmsg_flags & (NLM_F_CREATE
896 							 | NLM_F_EXCL))) {
897 			error = -EEXIST;
898 			goto err_unlock_ovs;
899 		}
900 		/* The unmasked key has to be the same for flow updates. */
901 		if (unlikely(!ovs_flow_cmp_unmasked_key(flow, &match))) {
902 			flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
903 			if (!flow) {
904 				error = -ENOENT;
905 				goto err_unlock_ovs;
906 			}
907 		}
908 		/* Update actions. */
909 		old_acts = ovsl_dereference(flow->sf_acts);
910 		rcu_assign_pointer(flow->sf_acts, acts);
911 
912 		if (unlikely(reply)) {
913 			error = ovs_flow_cmd_fill_info(flow,
914 						       ovs_header->dp_ifindex,
915 						       reply, info->snd_portid,
916 						       info->snd_seq, 0,
917 						       OVS_FLOW_CMD_NEW);
918 			BUG_ON(error < 0);
919 		}
920 		ovs_unlock();
921 
922 		ovs_nla_free_flow_actions(old_acts);
923 		ovs_flow_free(new_flow, false);
924 	}
925 
926 	if (reply)
927 		ovs_notify(&dp_flow_genl_family, reply, info);
928 	return 0;
929 
930 err_unlock_ovs:
931 	ovs_unlock();
932 	kfree_skb(reply);
933 err_kfree_acts:
934 	kfree(acts);
935 err_kfree_flow:
936 	ovs_flow_free(new_flow, false);
937 error:
938 	return error;
939 }
940 
941 static struct sw_flow_actions *get_flow_actions(const struct nlattr *a,
942 						const struct sw_flow_key *key,
943 						const struct sw_flow_mask *mask)
944 {
945 	struct sw_flow_actions *acts;
946 	struct sw_flow_key masked_key;
947 	int error;
948 
949 	acts = ovs_nla_alloc_flow_actions(nla_len(a));
950 	if (IS_ERR(acts))
951 		return acts;
952 
953 	ovs_flow_mask_key(&masked_key, key, mask);
954 	error = ovs_nla_copy_actions(a, &masked_key, 0, &acts);
955 	if (error) {
956 		OVS_NLERR("Flow actions may not be safe on all matching packets.\n");
957 		kfree(acts);
958 		return ERR_PTR(error);
959 	}
960 
961 	return acts;
962 }
963 
964 static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
965 {
966 	struct nlattr **a = info->attrs;
967 	struct ovs_header *ovs_header = info->userhdr;
968 	struct sw_flow_key key;
969 	struct sw_flow *flow;
970 	struct sw_flow_mask mask;
971 	struct sk_buff *reply = NULL;
972 	struct datapath *dp;
973 	struct sw_flow_actions *old_acts = NULL, *acts = NULL;
974 	struct sw_flow_match match;
975 	int error;
976 
977 	/* Extract key. */
978 	error = -EINVAL;
979 	if (!a[OVS_FLOW_ATTR_KEY])
980 		goto error;
981 
982 	ovs_match_init(&match, &key, &mask);
983 	error = ovs_nla_get_match(&match,
984 				  a[OVS_FLOW_ATTR_KEY], a[OVS_FLOW_ATTR_MASK]);
985 	if (error)
986 		goto error;
987 
988 	/* Validate actions. */
989 	if (a[OVS_FLOW_ATTR_ACTIONS]) {
990 		acts = get_flow_actions(a[OVS_FLOW_ATTR_ACTIONS], &key, &mask);
991 		if (IS_ERR(acts)) {
992 			error = PTR_ERR(acts);
993 			goto error;
994 		}
995 	}
996 
997 	/* Can allocate before locking if have acts. */
998 	if (acts) {
999 		reply = ovs_flow_cmd_alloc_info(acts, info, false);
1000 		if (IS_ERR(reply)) {
1001 			error = PTR_ERR(reply);
1002 			goto err_kfree_acts;
1003 		}
1004 	}
1005 
1006 	ovs_lock();
1007 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1008 	if (unlikely(!dp)) {
1009 		error = -ENODEV;
1010 		goto err_unlock_ovs;
1011 	}
1012 	/* Check that the flow exists. */
1013 	flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1014 	if (unlikely(!flow)) {
1015 		error = -ENOENT;
1016 		goto err_unlock_ovs;
1017 	}
1018 
1019 	/* Update actions, if present. */
1020 	if (likely(acts)) {
1021 		old_acts = ovsl_dereference(flow->sf_acts);
1022 		rcu_assign_pointer(flow->sf_acts, acts);
1023 
1024 		if (unlikely(reply)) {
1025 			error = ovs_flow_cmd_fill_info(flow,
1026 						       ovs_header->dp_ifindex,
1027 						       reply, info->snd_portid,
1028 						       info->snd_seq, 0,
1029 						       OVS_FLOW_CMD_NEW);
1030 			BUG_ON(error < 0);
1031 		}
1032 	} else {
1033 		/* Could not alloc without acts before locking. */
1034 		reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex,
1035 						info, OVS_FLOW_CMD_NEW, false);
1036 		if (unlikely(IS_ERR(reply))) {
1037 			error = PTR_ERR(reply);
1038 			goto err_unlock_ovs;
1039 		}
1040 	}
1041 
1042 	/* Clear stats. */
1043 	if (a[OVS_FLOW_ATTR_CLEAR])
1044 		ovs_flow_stats_clear(flow);
1045 	ovs_unlock();
1046 
1047 	if (reply)
1048 		ovs_notify(&dp_flow_genl_family, reply, info);
1049 	if (old_acts)
1050 		ovs_nla_free_flow_actions(old_acts);
1051 
1052 	return 0;
1053 
1054 err_unlock_ovs:
1055 	ovs_unlock();
1056 	kfree_skb(reply);
1057 err_kfree_acts:
1058 	kfree(acts);
1059 error:
1060 	return error;
1061 }
1062 
1063 static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
1064 {
1065 	struct nlattr **a = info->attrs;
1066 	struct ovs_header *ovs_header = info->userhdr;
1067 	struct sw_flow_key key;
1068 	struct sk_buff *reply;
1069 	struct sw_flow *flow;
1070 	struct datapath *dp;
1071 	struct sw_flow_match match;
1072 	int err;
1073 
1074 	if (!a[OVS_FLOW_ATTR_KEY]) {
1075 		OVS_NLERR("Flow get message rejected, Key attribute missing.\n");
1076 		return -EINVAL;
1077 	}
1078 
1079 	ovs_match_init(&match, &key, NULL);
1080 	err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
1081 	if (err)
1082 		return err;
1083 
1084 	ovs_lock();
1085 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1086 	if (!dp) {
1087 		err = -ENODEV;
1088 		goto unlock;
1089 	}
1090 
1091 	flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1092 	if (!flow) {
1093 		err = -ENOENT;
1094 		goto unlock;
1095 	}
1096 
1097 	reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex, info,
1098 					OVS_FLOW_CMD_NEW, true);
1099 	if (IS_ERR(reply)) {
1100 		err = PTR_ERR(reply);
1101 		goto unlock;
1102 	}
1103 
1104 	ovs_unlock();
1105 	return genlmsg_reply(reply, info);
1106 unlock:
1107 	ovs_unlock();
1108 	return err;
1109 }
1110 
1111 static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
1112 {
1113 	struct nlattr **a = info->attrs;
1114 	struct ovs_header *ovs_header = info->userhdr;
1115 	struct sw_flow_key key;
1116 	struct sk_buff *reply;
1117 	struct sw_flow *flow;
1118 	struct datapath *dp;
1119 	struct sw_flow_match match;
1120 	int err;
1121 
1122 	if (likely(a[OVS_FLOW_ATTR_KEY])) {
1123 		ovs_match_init(&match, &key, NULL);
1124 		err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
1125 		if (unlikely(err))
1126 			return err;
1127 	}
1128 
1129 	ovs_lock();
1130 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1131 	if (unlikely(!dp)) {
1132 		err = -ENODEV;
1133 		goto unlock;
1134 	}
1135 
1136 	if (unlikely(!a[OVS_FLOW_ATTR_KEY])) {
1137 		err = ovs_flow_tbl_flush(&dp->table);
1138 		goto unlock;
1139 	}
1140 
1141 	flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1142 	if (unlikely(!flow)) {
1143 		err = -ENOENT;
1144 		goto unlock;
1145 	}
1146 
1147 	ovs_flow_tbl_remove(&dp->table, flow);
1148 	ovs_unlock();
1149 
1150 	reply = ovs_flow_cmd_alloc_info((const struct sw_flow_actions __force *) flow->sf_acts,
1151 					info, false);
1152 	if (likely(reply)) {
1153 		if (likely(!IS_ERR(reply))) {
1154 			rcu_read_lock();	/*To keep RCU checker happy. */
1155 			err = ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex,
1156 						     reply, info->snd_portid,
1157 						     info->snd_seq, 0,
1158 						     OVS_FLOW_CMD_DEL);
1159 			rcu_read_unlock();
1160 			BUG_ON(err < 0);
1161 
1162 			ovs_notify(&dp_flow_genl_family, reply, info);
1163 		} else {
1164 			netlink_set_err(sock_net(skb->sk)->genl_sock, 0, 0, PTR_ERR(reply));
1165 		}
1166 	}
1167 
1168 	ovs_flow_free(flow, true);
1169 	return 0;
1170 unlock:
1171 	ovs_unlock();
1172 	return err;
1173 }
1174 
1175 static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1176 {
1177 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1178 	struct table_instance *ti;
1179 	struct datapath *dp;
1180 
1181 	rcu_read_lock();
1182 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1183 	if (!dp) {
1184 		rcu_read_unlock();
1185 		return -ENODEV;
1186 	}
1187 
1188 	ti = rcu_dereference(dp->table.ti);
1189 	for (;;) {
1190 		struct sw_flow *flow;
1191 		u32 bucket, obj;
1192 
1193 		bucket = cb->args[0];
1194 		obj = cb->args[1];
1195 		flow = ovs_flow_tbl_dump_next(ti, &bucket, &obj);
1196 		if (!flow)
1197 			break;
1198 
1199 		if (ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex, skb,
1200 					   NETLINK_CB(cb->skb).portid,
1201 					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
1202 					   OVS_FLOW_CMD_NEW) < 0)
1203 			break;
1204 
1205 		cb->args[0] = bucket;
1206 		cb->args[1] = obj;
1207 	}
1208 	rcu_read_unlock();
1209 	return skb->len;
1210 }
1211 
1212 static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = {
1213 	[OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED },
1214 	[OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED },
1215 	[OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG },
1216 };
1217 
1218 static const struct genl_ops dp_flow_genl_ops[] = {
1219 	{ .cmd = OVS_FLOW_CMD_NEW,
1220 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1221 	  .policy = flow_policy,
1222 	  .doit = ovs_flow_cmd_new
1223 	},
1224 	{ .cmd = OVS_FLOW_CMD_DEL,
1225 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1226 	  .policy = flow_policy,
1227 	  .doit = ovs_flow_cmd_del
1228 	},
1229 	{ .cmd = OVS_FLOW_CMD_GET,
1230 	  .flags = 0,		    /* OK for unprivileged users. */
1231 	  .policy = flow_policy,
1232 	  .doit = ovs_flow_cmd_get,
1233 	  .dumpit = ovs_flow_cmd_dump
1234 	},
1235 	{ .cmd = OVS_FLOW_CMD_SET,
1236 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1237 	  .policy = flow_policy,
1238 	  .doit = ovs_flow_cmd_set,
1239 	},
1240 };
1241 
1242 static struct genl_family dp_flow_genl_family = {
1243 	.id = GENL_ID_GENERATE,
1244 	.hdrsize = sizeof(struct ovs_header),
1245 	.name = OVS_FLOW_FAMILY,
1246 	.version = OVS_FLOW_VERSION,
1247 	.maxattr = OVS_FLOW_ATTR_MAX,
1248 	.netnsok = true,
1249 	.parallel_ops = true,
1250 	.ops = dp_flow_genl_ops,
1251 	.n_ops = ARRAY_SIZE(dp_flow_genl_ops),
1252 	.mcgrps = &ovs_dp_flow_multicast_group,
1253 	.n_mcgrps = 1,
1254 };
1255 
1256 static size_t ovs_dp_cmd_msg_size(void)
1257 {
1258 	size_t msgsize = NLMSG_ALIGN(sizeof(struct ovs_header));
1259 
1260 	msgsize += nla_total_size(IFNAMSIZ);
1261 	msgsize += nla_total_size(sizeof(struct ovs_dp_stats));
1262 	msgsize += nla_total_size(sizeof(struct ovs_dp_megaflow_stats));
1263 	msgsize += nla_total_size(sizeof(u32)); /* OVS_DP_ATTR_USER_FEATURES */
1264 
1265 	return msgsize;
1266 }
1267 
1268 /* Called with ovs_mutex or RCU read lock. */
1269 static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
1270 				u32 portid, u32 seq, u32 flags, u8 cmd)
1271 {
1272 	struct ovs_header *ovs_header;
1273 	struct ovs_dp_stats dp_stats;
1274 	struct ovs_dp_megaflow_stats dp_megaflow_stats;
1275 	int err;
1276 
1277 	ovs_header = genlmsg_put(skb, portid, seq, &dp_datapath_genl_family,
1278 				   flags, cmd);
1279 	if (!ovs_header)
1280 		goto error;
1281 
1282 	ovs_header->dp_ifindex = get_dpifindex(dp);
1283 
1284 	err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp));
1285 	if (err)
1286 		goto nla_put_failure;
1287 
1288 	get_dp_stats(dp, &dp_stats, &dp_megaflow_stats);
1289 	if (nla_put(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats),
1290 			&dp_stats))
1291 		goto nla_put_failure;
1292 
1293 	if (nla_put(skb, OVS_DP_ATTR_MEGAFLOW_STATS,
1294 			sizeof(struct ovs_dp_megaflow_stats),
1295 			&dp_megaflow_stats))
1296 		goto nla_put_failure;
1297 
1298 	if (nla_put_u32(skb, OVS_DP_ATTR_USER_FEATURES, dp->user_features))
1299 		goto nla_put_failure;
1300 
1301 	return genlmsg_end(skb, ovs_header);
1302 
1303 nla_put_failure:
1304 	genlmsg_cancel(skb, ovs_header);
1305 error:
1306 	return -EMSGSIZE;
1307 }
1308 
1309 static struct sk_buff *ovs_dp_cmd_alloc_info(struct genl_info *info)
1310 {
1311 	return genlmsg_new_unicast(ovs_dp_cmd_msg_size(), info, GFP_KERNEL);
1312 }
1313 
1314 /* Called with rcu_read_lock or ovs_mutex. */
1315 static struct datapath *lookup_datapath(struct net *net,
1316 					struct ovs_header *ovs_header,
1317 					struct nlattr *a[OVS_DP_ATTR_MAX + 1])
1318 {
1319 	struct datapath *dp;
1320 
1321 	if (!a[OVS_DP_ATTR_NAME])
1322 		dp = get_dp(net, ovs_header->dp_ifindex);
1323 	else {
1324 		struct vport *vport;
1325 
1326 		vport = ovs_vport_locate(net, nla_data(a[OVS_DP_ATTR_NAME]));
1327 		dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL;
1328 	}
1329 	return dp ? dp : ERR_PTR(-ENODEV);
1330 }
1331 
1332 static void ovs_dp_reset_user_features(struct sk_buff *skb, struct genl_info *info)
1333 {
1334 	struct datapath *dp;
1335 
1336 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1337 	if (IS_ERR(dp))
1338 		return;
1339 
1340 	WARN(dp->user_features, "Dropping previously announced user features\n");
1341 	dp->user_features = 0;
1342 }
1343 
1344 static void ovs_dp_change(struct datapath *dp, struct nlattr **a)
1345 {
1346 	if (a[OVS_DP_ATTR_USER_FEATURES])
1347 		dp->user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
1348 }
1349 
1350 static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
1351 {
1352 	struct nlattr **a = info->attrs;
1353 	struct vport_parms parms;
1354 	struct sk_buff *reply;
1355 	struct datapath *dp;
1356 	struct vport *vport;
1357 	struct ovs_net *ovs_net;
1358 	int err, i;
1359 
1360 	err = -EINVAL;
1361 	if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
1362 		goto err;
1363 
1364 	reply = ovs_dp_cmd_alloc_info(info);
1365 	if (!reply)
1366 		return -ENOMEM;
1367 
1368 	err = -ENOMEM;
1369 	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
1370 	if (dp == NULL)
1371 		goto err_free_reply;
1372 
1373 	ovs_dp_set_net(dp, hold_net(sock_net(skb->sk)));
1374 
1375 	/* Allocate table. */
1376 	err = ovs_flow_tbl_init(&dp->table);
1377 	if (err)
1378 		goto err_free_dp;
1379 
1380 	dp->stats_percpu = netdev_alloc_pcpu_stats(struct dp_stats_percpu);
1381 	if (!dp->stats_percpu) {
1382 		err = -ENOMEM;
1383 		goto err_destroy_table;
1384 	}
1385 
1386 	dp->ports = kmalloc(DP_VPORT_HASH_BUCKETS * sizeof(struct hlist_head),
1387 			    GFP_KERNEL);
1388 	if (!dp->ports) {
1389 		err = -ENOMEM;
1390 		goto err_destroy_percpu;
1391 	}
1392 
1393 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
1394 		INIT_HLIST_HEAD(&dp->ports[i]);
1395 
1396 	/* Set up our datapath device. */
1397 	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
1398 	parms.type = OVS_VPORT_TYPE_INTERNAL;
1399 	parms.options = NULL;
1400 	parms.dp = dp;
1401 	parms.port_no = OVSP_LOCAL;
1402 	parms.upcall_portids = a[OVS_DP_ATTR_UPCALL_PID];
1403 
1404 	ovs_dp_change(dp, a);
1405 
1406 	/* So far only local changes have been made, now need the lock. */
1407 	ovs_lock();
1408 
1409 	vport = new_vport(&parms);
1410 	if (IS_ERR(vport)) {
1411 		err = PTR_ERR(vport);
1412 		if (err == -EBUSY)
1413 			err = -EEXIST;
1414 
1415 		if (err == -EEXIST) {
1416 			/* An outdated user space instance that does not understand
1417 			 * the concept of user_features has attempted to create a new
1418 			 * datapath and is likely to reuse it. Drop all user features.
1419 			 */
1420 			if (info->genlhdr->version < OVS_DP_VER_FEATURES)
1421 				ovs_dp_reset_user_features(skb, info);
1422 		}
1423 
1424 		goto err_destroy_ports_array;
1425 	}
1426 
1427 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1428 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1429 	BUG_ON(err < 0);
1430 
1431 	ovs_net = net_generic(ovs_dp_get_net(dp), ovs_net_id);
1432 	list_add_tail_rcu(&dp->list_node, &ovs_net->dps);
1433 
1434 	ovs_unlock();
1435 
1436 	ovs_notify(&dp_datapath_genl_family, reply, info);
1437 	return 0;
1438 
1439 err_destroy_ports_array:
1440 	ovs_unlock();
1441 	kfree(dp->ports);
1442 err_destroy_percpu:
1443 	free_percpu(dp->stats_percpu);
1444 err_destroy_table:
1445 	ovs_flow_tbl_destroy(&dp->table, false);
1446 err_free_dp:
1447 	release_net(ovs_dp_get_net(dp));
1448 	kfree(dp);
1449 err_free_reply:
1450 	kfree_skb(reply);
1451 err:
1452 	return err;
1453 }
1454 
1455 /* Called with ovs_mutex. */
1456 static void __dp_destroy(struct datapath *dp)
1457 {
1458 	int i;
1459 
1460 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
1461 		struct vport *vport;
1462 		struct hlist_node *n;
1463 
1464 		hlist_for_each_entry_safe(vport, n, &dp->ports[i], dp_hash_node)
1465 			if (vport->port_no != OVSP_LOCAL)
1466 				ovs_dp_detach_port(vport);
1467 	}
1468 
1469 	list_del_rcu(&dp->list_node);
1470 
1471 	/* OVSP_LOCAL is datapath internal port. We need to make sure that
1472 	 * all ports in datapath are destroyed first before freeing datapath.
1473 	 */
1474 	ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
1475 
1476 	/* RCU destroy the flow table */
1477 	ovs_flow_tbl_destroy(&dp->table, true);
1478 
1479 	call_rcu(&dp->rcu, destroy_dp_rcu);
1480 }
1481 
1482 static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
1483 {
1484 	struct sk_buff *reply;
1485 	struct datapath *dp;
1486 	int err;
1487 
1488 	reply = ovs_dp_cmd_alloc_info(info);
1489 	if (!reply)
1490 		return -ENOMEM;
1491 
1492 	ovs_lock();
1493 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1494 	err = PTR_ERR(dp);
1495 	if (IS_ERR(dp))
1496 		goto err_unlock_free;
1497 
1498 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1499 				   info->snd_seq, 0, OVS_DP_CMD_DEL);
1500 	BUG_ON(err < 0);
1501 
1502 	__dp_destroy(dp);
1503 	ovs_unlock();
1504 
1505 	ovs_notify(&dp_datapath_genl_family, reply, info);
1506 
1507 	return 0;
1508 
1509 err_unlock_free:
1510 	ovs_unlock();
1511 	kfree_skb(reply);
1512 	return err;
1513 }
1514 
1515 static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
1516 {
1517 	struct sk_buff *reply;
1518 	struct datapath *dp;
1519 	int err;
1520 
1521 	reply = ovs_dp_cmd_alloc_info(info);
1522 	if (!reply)
1523 		return -ENOMEM;
1524 
1525 	ovs_lock();
1526 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1527 	err = PTR_ERR(dp);
1528 	if (IS_ERR(dp))
1529 		goto err_unlock_free;
1530 
1531 	ovs_dp_change(dp, info->attrs);
1532 
1533 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1534 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1535 	BUG_ON(err < 0);
1536 
1537 	ovs_unlock();
1538 	ovs_notify(&dp_datapath_genl_family, reply, info);
1539 
1540 	return 0;
1541 
1542 err_unlock_free:
1543 	ovs_unlock();
1544 	kfree_skb(reply);
1545 	return err;
1546 }
1547 
1548 static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
1549 {
1550 	struct sk_buff *reply;
1551 	struct datapath *dp;
1552 	int err;
1553 
1554 	reply = ovs_dp_cmd_alloc_info(info);
1555 	if (!reply)
1556 		return -ENOMEM;
1557 
1558 	rcu_read_lock();
1559 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1560 	if (IS_ERR(dp)) {
1561 		err = PTR_ERR(dp);
1562 		goto err_unlock_free;
1563 	}
1564 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1565 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1566 	BUG_ON(err < 0);
1567 	rcu_read_unlock();
1568 
1569 	return genlmsg_reply(reply, info);
1570 
1571 err_unlock_free:
1572 	rcu_read_unlock();
1573 	kfree_skb(reply);
1574 	return err;
1575 }
1576 
1577 static int ovs_dp_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1578 {
1579 	struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
1580 	struct datapath *dp;
1581 	int skip = cb->args[0];
1582 	int i = 0;
1583 
1584 	rcu_read_lock();
1585 	list_for_each_entry_rcu(dp, &ovs_net->dps, list_node) {
1586 		if (i >= skip &&
1587 		    ovs_dp_cmd_fill_info(dp, skb, NETLINK_CB(cb->skb).portid,
1588 					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1589 					 OVS_DP_CMD_NEW) < 0)
1590 			break;
1591 		i++;
1592 	}
1593 	rcu_read_unlock();
1594 
1595 	cb->args[0] = i;
1596 
1597 	return skb->len;
1598 }
1599 
1600 static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
1601 	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1602 	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1603 	[OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 },
1604 };
1605 
1606 static const struct genl_ops dp_datapath_genl_ops[] = {
1607 	{ .cmd = OVS_DP_CMD_NEW,
1608 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1609 	  .policy = datapath_policy,
1610 	  .doit = ovs_dp_cmd_new
1611 	},
1612 	{ .cmd = OVS_DP_CMD_DEL,
1613 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1614 	  .policy = datapath_policy,
1615 	  .doit = ovs_dp_cmd_del
1616 	},
1617 	{ .cmd = OVS_DP_CMD_GET,
1618 	  .flags = 0,		    /* OK for unprivileged users. */
1619 	  .policy = datapath_policy,
1620 	  .doit = ovs_dp_cmd_get,
1621 	  .dumpit = ovs_dp_cmd_dump
1622 	},
1623 	{ .cmd = OVS_DP_CMD_SET,
1624 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1625 	  .policy = datapath_policy,
1626 	  .doit = ovs_dp_cmd_set,
1627 	},
1628 };
1629 
1630 static struct genl_family dp_datapath_genl_family = {
1631 	.id = GENL_ID_GENERATE,
1632 	.hdrsize = sizeof(struct ovs_header),
1633 	.name = OVS_DATAPATH_FAMILY,
1634 	.version = OVS_DATAPATH_VERSION,
1635 	.maxattr = OVS_DP_ATTR_MAX,
1636 	.netnsok = true,
1637 	.parallel_ops = true,
1638 	.ops = dp_datapath_genl_ops,
1639 	.n_ops = ARRAY_SIZE(dp_datapath_genl_ops),
1640 	.mcgrps = &ovs_dp_datapath_multicast_group,
1641 	.n_mcgrps = 1,
1642 };
1643 
1644 /* Called with ovs_mutex or RCU read lock. */
1645 static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
1646 				   u32 portid, u32 seq, u32 flags, u8 cmd)
1647 {
1648 	struct ovs_header *ovs_header;
1649 	struct ovs_vport_stats vport_stats;
1650 	int err;
1651 
1652 	ovs_header = genlmsg_put(skb, portid, seq, &dp_vport_genl_family,
1653 				 flags, cmd);
1654 	if (!ovs_header)
1655 		return -EMSGSIZE;
1656 
1657 	ovs_header->dp_ifindex = get_dpifindex(vport->dp);
1658 
1659 	if (nla_put_u32(skb, OVS_VPORT_ATTR_PORT_NO, vport->port_no) ||
1660 	    nla_put_u32(skb, OVS_VPORT_ATTR_TYPE, vport->ops->type) ||
1661 	    nla_put_string(skb, OVS_VPORT_ATTR_NAME,
1662 			   vport->ops->get_name(vport)))
1663 		goto nla_put_failure;
1664 
1665 	ovs_vport_get_stats(vport, &vport_stats);
1666 	if (nla_put(skb, OVS_VPORT_ATTR_STATS, sizeof(struct ovs_vport_stats),
1667 		    &vport_stats))
1668 		goto nla_put_failure;
1669 
1670 	if (ovs_vport_get_upcall_portids(vport, skb))
1671 		goto nla_put_failure;
1672 
1673 	err = ovs_vport_get_options(vport, skb);
1674 	if (err == -EMSGSIZE)
1675 		goto error;
1676 
1677 	return genlmsg_end(skb, ovs_header);
1678 
1679 nla_put_failure:
1680 	err = -EMSGSIZE;
1681 error:
1682 	genlmsg_cancel(skb, ovs_header);
1683 	return err;
1684 }
1685 
1686 static struct sk_buff *ovs_vport_cmd_alloc_info(void)
1687 {
1688 	return nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1689 }
1690 
1691 /* Called with ovs_mutex, only via ovs_dp_notify_wq(). */
1692 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, u32 portid,
1693 					 u32 seq, u8 cmd)
1694 {
1695 	struct sk_buff *skb;
1696 	int retval;
1697 
1698 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1699 	if (!skb)
1700 		return ERR_PTR(-ENOMEM);
1701 
1702 	retval = ovs_vport_cmd_fill_info(vport, skb, portid, seq, 0, cmd);
1703 	BUG_ON(retval < 0);
1704 
1705 	return skb;
1706 }
1707 
1708 /* Called with ovs_mutex or RCU read lock. */
1709 static struct vport *lookup_vport(struct net *net,
1710 				  struct ovs_header *ovs_header,
1711 				  struct nlattr *a[OVS_VPORT_ATTR_MAX + 1])
1712 {
1713 	struct datapath *dp;
1714 	struct vport *vport;
1715 
1716 	if (a[OVS_VPORT_ATTR_NAME]) {
1717 		vport = ovs_vport_locate(net, nla_data(a[OVS_VPORT_ATTR_NAME]));
1718 		if (!vport)
1719 			return ERR_PTR(-ENODEV);
1720 		if (ovs_header->dp_ifindex &&
1721 		    ovs_header->dp_ifindex != get_dpifindex(vport->dp))
1722 			return ERR_PTR(-ENODEV);
1723 		return vport;
1724 	} else if (a[OVS_VPORT_ATTR_PORT_NO]) {
1725 		u32 port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
1726 
1727 		if (port_no >= DP_MAX_PORTS)
1728 			return ERR_PTR(-EFBIG);
1729 
1730 		dp = get_dp(net, ovs_header->dp_ifindex);
1731 		if (!dp)
1732 			return ERR_PTR(-ENODEV);
1733 
1734 		vport = ovs_vport_ovsl_rcu(dp, port_no);
1735 		if (!vport)
1736 			return ERR_PTR(-ENODEV);
1737 		return vport;
1738 	} else
1739 		return ERR_PTR(-EINVAL);
1740 }
1741 
1742 static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
1743 {
1744 	struct nlattr **a = info->attrs;
1745 	struct ovs_header *ovs_header = info->userhdr;
1746 	struct vport_parms parms;
1747 	struct sk_buff *reply;
1748 	struct vport *vport;
1749 	struct datapath *dp;
1750 	u32 port_no;
1751 	int err;
1752 
1753 	if (!a[OVS_VPORT_ATTR_NAME] || !a[OVS_VPORT_ATTR_TYPE] ||
1754 	    !a[OVS_VPORT_ATTR_UPCALL_PID])
1755 		return -EINVAL;
1756 
1757 	port_no = a[OVS_VPORT_ATTR_PORT_NO]
1758 		? nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]) : 0;
1759 	if (port_no >= DP_MAX_PORTS)
1760 		return -EFBIG;
1761 
1762 	reply = ovs_vport_cmd_alloc_info();
1763 	if (!reply)
1764 		return -ENOMEM;
1765 
1766 	ovs_lock();
1767 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1768 	err = -ENODEV;
1769 	if (!dp)
1770 		goto exit_unlock_free;
1771 
1772 	if (port_no) {
1773 		vport = ovs_vport_ovsl(dp, port_no);
1774 		err = -EBUSY;
1775 		if (vport)
1776 			goto exit_unlock_free;
1777 	} else {
1778 		for (port_no = 1; ; port_no++) {
1779 			if (port_no >= DP_MAX_PORTS) {
1780 				err = -EFBIG;
1781 				goto exit_unlock_free;
1782 			}
1783 			vport = ovs_vport_ovsl(dp, port_no);
1784 			if (!vport)
1785 				break;
1786 		}
1787 	}
1788 
1789 	parms.name = nla_data(a[OVS_VPORT_ATTR_NAME]);
1790 	parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
1791 	parms.options = a[OVS_VPORT_ATTR_OPTIONS];
1792 	parms.dp = dp;
1793 	parms.port_no = port_no;
1794 	parms.upcall_portids = a[OVS_VPORT_ATTR_UPCALL_PID];
1795 
1796 	vport = new_vport(&parms);
1797 	err = PTR_ERR(vport);
1798 	if (IS_ERR(vport))
1799 		goto exit_unlock_free;
1800 
1801 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1802 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
1803 	BUG_ON(err < 0);
1804 	ovs_unlock();
1805 
1806 	ovs_notify(&dp_vport_genl_family, reply, info);
1807 	return 0;
1808 
1809 exit_unlock_free:
1810 	ovs_unlock();
1811 	kfree_skb(reply);
1812 	return err;
1813 }
1814 
1815 static int ovs_vport_cmd_set(struct sk_buff *skb, struct genl_info *info)
1816 {
1817 	struct nlattr **a = info->attrs;
1818 	struct sk_buff *reply;
1819 	struct vport *vport;
1820 	int err;
1821 
1822 	reply = ovs_vport_cmd_alloc_info();
1823 	if (!reply)
1824 		return -ENOMEM;
1825 
1826 	ovs_lock();
1827 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
1828 	err = PTR_ERR(vport);
1829 	if (IS_ERR(vport))
1830 		goto exit_unlock_free;
1831 
1832 	if (a[OVS_VPORT_ATTR_TYPE] &&
1833 	    nla_get_u32(a[OVS_VPORT_ATTR_TYPE]) != vport->ops->type) {
1834 		err = -EINVAL;
1835 		goto exit_unlock_free;
1836 	}
1837 
1838 	if (a[OVS_VPORT_ATTR_OPTIONS]) {
1839 		err = ovs_vport_set_options(vport, a[OVS_VPORT_ATTR_OPTIONS]);
1840 		if (err)
1841 			goto exit_unlock_free;
1842 	}
1843 
1844 
1845 	if (a[OVS_VPORT_ATTR_UPCALL_PID]) {
1846 		struct nlattr *ids = a[OVS_VPORT_ATTR_UPCALL_PID];
1847 
1848 		err = ovs_vport_set_upcall_portids(vport, ids);
1849 		if (err)
1850 			goto exit_unlock_free;
1851 	}
1852 
1853 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1854 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
1855 	BUG_ON(err < 0);
1856 
1857 	ovs_unlock();
1858 	ovs_notify(&dp_vport_genl_family, reply, info);
1859 	return 0;
1860 
1861 exit_unlock_free:
1862 	ovs_unlock();
1863 	kfree_skb(reply);
1864 	return err;
1865 }
1866 
1867 static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info)
1868 {
1869 	struct nlattr **a = info->attrs;
1870 	struct sk_buff *reply;
1871 	struct vport *vport;
1872 	int err;
1873 
1874 	reply = ovs_vport_cmd_alloc_info();
1875 	if (!reply)
1876 		return -ENOMEM;
1877 
1878 	ovs_lock();
1879 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
1880 	err = PTR_ERR(vport);
1881 	if (IS_ERR(vport))
1882 		goto exit_unlock_free;
1883 
1884 	if (vport->port_no == OVSP_LOCAL) {
1885 		err = -EINVAL;
1886 		goto exit_unlock_free;
1887 	}
1888 
1889 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1890 				      info->snd_seq, 0, OVS_VPORT_CMD_DEL);
1891 	BUG_ON(err < 0);
1892 	ovs_dp_detach_port(vport);
1893 	ovs_unlock();
1894 
1895 	ovs_notify(&dp_vport_genl_family, reply, info);
1896 	return 0;
1897 
1898 exit_unlock_free:
1899 	ovs_unlock();
1900 	kfree_skb(reply);
1901 	return err;
1902 }
1903 
1904 static int ovs_vport_cmd_get(struct sk_buff *skb, struct genl_info *info)
1905 {
1906 	struct nlattr **a = info->attrs;
1907 	struct ovs_header *ovs_header = info->userhdr;
1908 	struct sk_buff *reply;
1909 	struct vport *vport;
1910 	int err;
1911 
1912 	reply = ovs_vport_cmd_alloc_info();
1913 	if (!reply)
1914 		return -ENOMEM;
1915 
1916 	rcu_read_lock();
1917 	vport = lookup_vport(sock_net(skb->sk), ovs_header, a);
1918 	err = PTR_ERR(vport);
1919 	if (IS_ERR(vport))
1920 		goto exit_unlock_free;
1921 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1922 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
1923 	BUG_ON(err < 0);
1924 	rcu_read_unlock();
1925 
1926 	return genlmsg_reply(reply, info);
1927 
1928 exit_unlock_free:
1929 	rcu_read_unlock();
1930 	kfree_skb(reply);
1931 	return err;
1932 }
1933 
1934 static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1935 {
1936 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1937 	struct datapath *dp;
1938 	int bucket = cb->args[0], skip = cb->args[1];
1939 	int i, j = 0;
1940 
1941 	rcu_read_lock();
1942 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1943 	if (!dp) {
1944 		rcu_read_unlock();
1945 		return -ENODEV;
1946 	}
1947 	for (i = bucket; i < DP_VPORT_HASH_BUCKETS; i++) {
1948 		struct vport *vport;
1949 
1950 		j = 0;
1951 		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) {
1952 			if (j >= skip &&
1953 			    ovs_vport_cmd_fill_info(vport, skb,
1954 						    NETLINK_CB(cb->skb).portid,
1955 						    cb->nlh->nlmsg_seq,
1956 						    NLM_F_MULTI,
1957 						    OVS_VPORT_CMD_NEW) < 0)
1958 				goto out;
1959 
1960 			j++;
1961 		}
1962 		skip = 0;
1963 	}
1964 out:
1965 	rcu_read_unlock();
1966 
1967 	cb->args[0] = i;
1968 	cb->args[1] = j;
1969 
1970 	return skb->len;
1971 }
1972 
1973 static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
1974 	[OVS_VPORT_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1975 	[OVS_VPORT_ATTR_STATS] = { .len = sizeof(struct ovs_vport_stats) },
1976 	[OVS_VPORT_ATTR_PORT_NO] = { .type = NLA_U32 },
1977 	[OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 },
1978 	[OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1979 	[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
1980 };
1981 
1982 static const struct genl_ops dp_vport_genl_ops[] = {
1983 	{ .cmd = OVS_VPORT_CMD_NEW,
1984 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1985 	  .policy = vport_policy,
1986 	  .doit = ovs_vport_cmd_new
1987 	},
1988 	{ .cmd = OVS_VPORT_CMD_DEL,
1989 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1990 	  .policy = vport_policy,
1991 	  .doit = ovs_vport_cmd_del
1992 	},
1993 	{ .cmd = OVS_VPORT_CMD_GET,
1994 	  .flags = 0,		    /* OK for unprivileged users. */
1995 	  .policy = vport_policy,
1996 	  .doit = ovs_vport_cmd_get,
1997 	  .dumpit = ovs_vport_cmd_dump
1998 	},
1999 	{ .cmd = OVS_VPORT_CMD_SET,
2000 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2001 	  .policy = vport_policy,
2002 	  .doit = ovs_vport_cmd_set,
2003 	},
2004 };
2005 
2006 struct genl_family dp_vport_genl_family = {
2007 	.id = GENL_ID_GENERATE,
2008 	.hdrsize = sizeof(struct ovs_header),
2009 	.name = OVS_VPORT_FAMILY,
2010 	.version = OVS_VPORT_VERSION,
2011 	.maxattr = OVS_VPORT_ATTR_MAX,
2012 	.netnsok = true,
2013 	.parallel_ops = true,
2014 	.ops = dp_vport_genl_ops,
2015 	.n_ops = ARRAY_SIZE(dp_vport_genl_ops),
2016 	.mcgrps = &ovs_dp_vport_multicast_group,
2017 	.n_mcgrps = 1,
2018 };
2019 
2020 static struct genl_family * const dp_genl_families[] = {
2021 	&dp_datapath_genl_family,
2022 	&dp_vport_genl_family,
2023 	&dp_flow_genl_family,
2024 	&dp_packet_genl_family,
2025 };
2026 
2027 static void dp_unregister_genl(int n_families)
2028 {
2029 	int i;
2030 
2031 	for (i = 0; i < n_families; i++)
2032 		genl_unregister_family(dp_genl_families[i]);
2033 }
2034 
2035 static int dp_register_genl(void)
2036 {
2037 	int err;
2038 	int i;
2039 
2040 	for (i = 0; i < ARRAY_SIZE(dp_genl_families); i++) {
2041 
2042 		err = genl_register_family(dp_genl_families[i]);
2043 		if (err)
2044 			goto error;
2045 	}
2046 
2047 	return 0;
2048 
2049 error:
2050 	dp_unregister_genl(i);
2051 	return err;
2052 }
2053 
2054 static int __net_init ovs_init_net(struct net *net)
2055 {
2056 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2057 
2058 	INIT_LIST_HEAD(&ovs_net->dps);
2059 	INIT_WORK(&ovs_net->dp_notify_work, ovs_dp_notify_wq);
2060 	return 0;
2061 }
2062 
2063 static void __net_exit ovs_exit_net(struct net *net)
2064 {
2065 	struct datapath *dp, *dp_next;
2066 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2067 
2068 	ovs_lock();
2069 	list_for_each_entry_safe(dp, dp_next, &ovs_net->dps, list_node)
2070 		__dp_destroy(dp);
2071 	ovs_unlock();
2072 
2073 	cancel_work_sync(&ovs_net->dp_notify_work);
2074 }
2075 
2076 static struct pernet_operations ovs_net_ops = {
2077 	.init = ovs_init_net,
2078 	.exit = ovs_exit_net,
2079 	.id   = &ovs_net_id,
2080 	.size = sizeof(struct ovs_net),
2081 };
2082 
2083 static int __init dp_init(void)
2084 {
2085 	int err;
2086 
2087 	BUILD_BUG_ON(sizeof(struct ovs_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb));
2088 
2089 	pr_info("Open vSwitch switching datapath\n");
2090 
2091 	err = action_fifos_init();
2092 	if (err)
2093 		goto error;
2094 
2095 	err = ovs_internal_dev_rtnl_link_register();
2096 	if (err)
2097 		goto error_action_fifos_exit;
2098 
2099 	err = ovs_flow_init();
2100 	if (err)
2101 		goto error_unreg_rtnl_link;
2102 
2103 	err = ovs_vport_init();
2104 	if (err)
2105 		goto error_flow_exit;
2106 
2107 	err = register_pernet_device(&ovs_net_ops);
2108 	if (err)
2109 		goto error_vport_exit;
2110 
2111 	err = register_netdevice_notifier(&ovs_dp_device_notifier);
2112 	if (err)
2113 		goto error_netns_exit;
2114 
2115 	err = dp_register_genl();
2116 	if (err < 0)
2117 		goto error_unreg_notifier;
2118 
2119 	return 0;
2120 
2121 error_unreg_notifier:
2122 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2123 error_netns_exit:
2124 	unregister_pernet_device(&ovs_net_ops);
2125 error_vport_exit:
2126 	ovs_vport_exit();
2127 error_flow_exit:
2128 	ovs_flow_exit();
2129 error_unreg_rtnl_link:
2130 	ovs_internal_dev_rtnl_link_unregister();
2131 error_action_fifos_exit:
2132 	action_fifos_exit();
2133 error:
2134 	return err;
2135 }
2136 
2137 static void dp_cleanup(void)
2138 {
2139 	dp_unregister_genl(ARRAY_SIZE(dp_genl_families));
2140 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2141 	unregister_pernet_device(&ovs_net_ops);
2142 	rcu_barrier();
2143 	ovs_vport_exit();
2144 	ovs_flow_exit();
2145 	ovs_internal_dev_rtnl_link_unregister();
2146 	action_fifos_exit();
2147 }
2148 
2149 module_init(dp_init);
2150 module_exit(dp_cleanup);
2151 
2152 MODULE_DESCRIPTION("Open vSwitch switching datapath");
2153 MODULE_LICENSE("GPL");
2154