xref: /openbmc/linux/net/openvswitch/datapath.c (revision 609e478b)
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 
328 	/* Queue all of the segments. */
329 	skb = segs;
330 	do {
331 		err = queue_userspace_packet(dp, skb, upcall_info);
332 		if (err)
333 			break;
334 
335 		if (skb == segs && gso_type & SKB_GSO_UDP) {
336 			/* The initial flow key extracted by ovs_flow_extract()
337 			 * in this case is for a first fragment, so we need to
338 			 * properly mark later fragments.
339 			 */
340 			later_key = *upcall_info->key;
341 			later_key.ip.frag = OVS_FRAG_TYPE_LATER;
342 
343 			later_info = *upcall_info;
344 			later_info.key = &later_key;
345 			upcall_info = &later_info;
346 		}
347 	} while ((skb = skb->next));
348 
349 	/* Free all of the segments. */
350 	skb = segs;
351 	do {
352 		nskb = skb->next;
353 		if (err)
354 			kfree_skb(skb);
355 		else
356 			consume_skb(skb);
357 	} while ((skb = nskb));
358 	return err;
359 }
360 
361 static size_t key_attr_size(void)
362 {
363 	return    nla_total_size(4)   /* OVS_KEY_ATTR_PRIORITY */
364 		+ nla_total_size(0)   /* OVS_KEY_ATTR_TUNNEL */
365 		  + nla_total_size(8)   /* OVS_TUNNEL_KEY_ATTR_ID */
366 		  + nla_total_size(4)   /* OVS_TUNNEL_KEY_ATTR_IPV4_SRC */
367 		  + nla_total_size(4)   /* OVS_TUNNEL_KEY_ATTR_IPV4_DST */
368 		  + nla_total_size(1)   /* OVS_TUNNEL_KEY_ATTR_TOS */
369 		  + nla_total_size(1)   /* OVS_TUNNEL_KEY_ATTR_TTL */
370 		  + nla_total_size(0)   /* OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT */
371 		  + nla_total_size(0)   /* OVS_TUNNEL_KEY_ATTR_CSUM */
372 		  + nla_total_size(0)   /* OVS_TUNNEL_KEY_ATTR_OAM */
373 		  + nla_total_size(256)   /* OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS */
374 		+ nla_total_size(4)   /* OVS_KEY_ATTR_IN_PORT */
375 		+ nla_total_size(4)   /* OVS_KEY_ATTR_SKB_MARK */
376 		+ nla_total_size(12)  /* OVS_KEY_ATTR_ETHERNET */
377 		+ nla_total_size(2)   /* OVS_KEY_ATTR_ETHERTYPE */
378 		+ nla_total_size(4)   /* OVS_KEY_ATTR_8021Q */
379 		+ nla_total_size(0)   /* OVS_KEY_ATTR_ENCAP */
380 		+ nla_total_size(2)   /* OVS_KEY_ATTR_ETHERTYPE */
381 		+ nla_total_size(40)  /* OVS_KEY_ATTR_IPV6 */
382 		+ nla_total_size(2)   /* OVS_KEY_ATTR_ICMPV6 */
383 		+ nla_total_size(28); /* OVS_KEY_ATTR_ND */
384 }
385 
386 static size_t upcall_msg_size(const struct nlattr *userdata,
387 			      unsigned int hdrlen)
388 {
389 	size_t size = NLMSG_ALIGN(sizeof(struct ovs_header))
390 		+ nla_total_size(hdrlen) /* OVS_PACKET_ATTR_PACKET */
391 		+ nla_total_size(key_attr_size()); /* OVS_PACKET_ATTR_KEY */
392 
393 	/* OVS_PACKET_ATTR_USERDATA */
394 	if (userdata)
395 		size += NLA_ALIGN(userdata->nla_len);
396 
397 	return size;
398 }
399 
400 static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
401 				  const struct dp_upcall_info *upcall_info)
402 {
403 	struct ovs_header *upcall;
404 	struct sk_buff *nskb = NULL;
405 	struct sk_buff *user_skb = NULL; /* to be queued to userspace */
406 	struct nlattr *nla;
407 	struct genl_info info = {
408 		.dst_sk = ovs_dp_get_net(dp)->genl_sock,
409 		.snd_portid = upcall_info->portid,
410 	};
411 	size_t len;
412 	unsigned int hlen;
413 	int err, dp_ifindex;
414 
415 	dp_ifindex = get_dpifindex(dp);
416 	if (!dp_ifindex)
417 		return -ENODEV;
418 
419 	if (vlan_tx_tag_present(skb)) {
420 		nskb = skb_clone(skb, GFP_ATOMIC);
421 		if (!nskb)
422 			return -ENOMEM;
423 
424 		nskb = __vlan_put_tag(nskb, nskb->vlan_proto, vlan_tx_tag_get(nskb));
425 		if (!nskb)
426 			return -ENOMEM;
427 
428 		nskb->vlan_tci = 0;
429 		skb = nskb;
430 	}
431 
432 	if (nla_attr_size(skb->len) > USHRT_MAX) {
433 		err = -EFBIG;
434 		goto out;
435 	}
436 
437 	/* Complete checksum if needed */
438 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
439 	    (err = skb_checksum_help(skb)))
440 		goto out;
441 
442 	/* Older versions of OVS user space enforce alignment of the last
443 	 * Netlink attribute to NLA_ALIGNTO which would require extensive
444 	 * padding logic. Only perform zerocopy if padding is not required.
445 	 */
446 	if (dp->user_features & OVS_DP_F_UNALIGNED)
447 		hlen = skb_zerocopy_headlen(skb);
448 	else
449 		hlen = skb->len;
450 
451 	len = upcall_msg_size(upcall_info->userdata, hlen);
452 	user_skb = genlmsg_new_unicast(len, &info, GFP_ATOMIC);
453 	if (!user_skb) {
454 		err = -ENOMEM;
455 		goto out;
456 	}
457 
458 	upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
459 			     0, upcall_info->cmd);
460 	upcall->dp_ifindex = dp_ifindex;
461 
462 	nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_KEY);
463 	err = ovs_nla_put_flow(upcall_info->key, upcall_info->key, user_skb);
464 	BUG_ON(err);
465 	nla_nest_end(user_skb, nla);
466 
467 	if (upcall_info->userdata)
468 		__nla_put(user_skb, OVS_PACKET_ATTR_USERDATA,
469 			  nla_len(upcall_info->userdata),
470 			  nla_data(upcall_info->userdata));
471 
472 	/* Only reserve room for attribute header, packet data is added
473 	 * in skb_zerocopy() */
474 	if (!(nla = nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, 0))) {
475 		err = -ENOBUFS;
476 		goto out;
477 	}
478 	nla->nla_len = nla_attr_size(skb->len);
479 
480 	err = skb_zerocopy(user_skb, skb, skb->len, hlen);
481 	if (err)
482 		goto out;
483 
484 	/* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */
485 	if (!(dp->user_features & OVS_DP_F_UNALIGNED)) {
486 		size_t plen = NLA_ALIGN(user_skb->len) - user_skb->len;
487 
488 		if (plen > 0)
489 			memset(skb_put(user_skb, plen), 0, plen);
490 	}
491 
492 	((struct nlmsghdr *) user_skb->data)->nlmsg_len = user_skb->len;
493 
494 	err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
495 	user_skb = NULL;
496 out:
497 	if (err)
498 		skb_tx_error(skb);
499 	kfree_skb(user_skb);
500 	kfree_skb(nskb);
501 	return err;
502 }
503 
504 static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
505 {
506 	struct ovs_header *ovs_header = info->userhdr;
507 	struct nlattr **a = info->attrs;
508 	struct sw_flow_actions *acts;
509 	struct sk_buff *packet;
510 	struct sw_flow *flow;
511 	struct datapath *dp;
512 	struct ethhdr *eth;
513 	struct vport *input_vport;
514 	int len;
515 	int err;
516 
517 	err = -EINVAL;
518 	if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] ||
519 	    !a[OVS_PACKET_ATTR_ACTIONS])
520 		goto err;
521 
522 	len = nla_len(a[OVS_PACKET_ATTR_PACKET]);
523 	packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL);
524 	err = -ENOMEM;
525 	if (!packet)
526 		goto err;
527 	skb_reserve(packet, NET_IP_ALIGN);
528 
529 	nla_memcpy(__skb_put(packet, len), a[OVS_PACKET_ATTR_PACKET], len);
530 
531 	skb_reset_mac_header(packet);
532 	eth = eth_hdr(packet);
533 
534 	/* Normally, setting the skb 'protocol' field would be handled by a
535 	 * call to eth_type_trans(), but it assumes there's a sending
536 	 * device, which we may not have. */
537 	if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN)
538 		packet->protocol = eth->h_proto;
539 	else
540 		packet->protocol = htons(ETH_P_802_2);
541 
542 	/* Build an sw_flow for sending this packet. */
543 	flow = ovs_flow_alloc();
544 	err = PTR_ERR(flow);
545 	if (IS_ERR(flow))
546 		goto err_kfree_skb;
547 
548 	err = ovs_flow_key_extract_userspace(a[OVS_PACKET_ATTR_KEY], packet,
549 					     &flow->key);
550 	if (err)
551 		goto err_flow_free;
552 
553 	acts = ovs_nla_alloc_flow_actions(nla_len(a[OVS_PACKET_ATTR_ACTIONS]));
554 	err = PTR_ERR(acts);
555 	if (IS_ERR(acts))
556 		goto err_flow_free;
557 
558 	err = ovs_nla_copy_actions(a[OVS_PACKET_ATTR_ACTIONS],
559 				   &flow->key, 0, &acts);
560 	if (err)
561 		goto err_flow_free;
562 
563 	rcu_assign_pointer(flow->sf_acts, acts);
564 
565 	OVS_CB(packet)->egress_tun_info = NULL;
566 	OVS_CB(packet)->flow = flow;
567 	packet->priority = flow->key.phy.priority;
568 	packet->mark = flow->key.phy.skb_mark;
569 
570 	rcu_read_lock();
571 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
572 	err = -ENODEV;
573 	if (!dp)
574 		goto err_unlock;
575 
576 	input_vport = ovs_vport_rcu(dp, flow->key.phy.in_port);
577 	if (!input_vport)
578 		input_vport = ovs_vport_rcu(dp, OVSP_LOCAL);
579 
580 	if (!input_vport)
581 		goto err_unlock;
582 
583 	OVS_CB(packet)->input_vport = input_vport;
584 
585 	local_bh_disable();
586 	err = ovs_execute_actions(dp, packet, &flow->key);
587 	local_bh_enable();
588 	rcu_read_unlock();
589 
590 	ovs_flow_free(flow, false);
591 	return err;
592 
593 err_unlock:
594 	rcu_read_unlock();
595 err_flow_free:
596 	ovs_flow_free(flow, false);
597 err_kfree_skb:
598 	kfree_skb(packet);
599 err:
600 	return err;
601 }
602 
603 static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = {
604 	[OVS_PACKET_ATTR_PACKET] = { .len = ETH_HLEN },
605 	[OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED },
606 	[OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED },
607 };
608 
609 static const struct genl_ops dp_packet_genl_ops[] = {
610 	{ .cmd = OVS_PACKET_CMD_EXECUTE,
611 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
612 	  .policy = packet_policy,
613 	  .doit = ovs_packet_cmd_execute
614 	}
615 };
616 
617 static struct genl_family dp_packet_genl_family = {
618 	.id = GENL_ID_GENERATE,
619 	.hdrsize = sizeof(struct ovs_header),
620 	.name = OVS_PACKET_FAMILY,
621 	.version = OVS_PACKET_VERSION,
622 	.maxattr = OVS_PACKET_ATTR_MAX,
623 	.netnsok = true,
624 	.parallel_ops = true,
625 	.ops = dp_packet_genl_ops,
626 	.n_ops = ARRAY_SIZE(dp_packet_genl_ops),
627 };
628 
629 static void get_dp_stats(struct datapath *dp, struct ovs_dp_stats *stats,
630 			 struct ovs_dp_megaflow_stats *mega_stats)
631 {
632 	int i;
633 
634 	memset(mega_stats, 0, sizeof(*mega_stats));
635 
636 	stats->n_flows = ovs_flow_tbl_count(&dp->table);
637 	mega_stats->n_masks = ovs_flow_tbl_num_masks(&dp->table);
638 
639 	stats->n_hit = stats->n_missed = stats->n_lost = 0;
640 
641 	for_each_possible_cpu(i) {
642 		const struct dp_stats_percpu *percpu_stats;
643 		struct dp_stats_percpu local_stats;
644 		unsigned int start;
645 
646 		percpu_stats = per_cpu_ptr(dp->stats_percpu, i);
647 
648 		do {
649 			start = u64_stats_fetch_begin_irq(&percpu_stats->syncp);
650 			local_stats = *percpu_stats;
651 		} while (u64_stats_fetch_retry_irq(&percpu_stats->syncp, start));
652 
653 		stats->n_hit += local_stats.n_hit;
654 		stats->n_missed += local_stats.n_missed;
655 		stats->n_lost += local_stats.n_lost;
656 		mega_stats->n_mask_hit += local_stats.n_mask_hit;
657 	}
658 }
659 
660 static size_t ovs_flow_cmd_msg_size(const struct sw_flow_actions *acts)
661 {
662 	return NLMSG_ALIGN(sizeof(struct ovs_header))
663 		+ nla_total_size(key_attr_size()) /* OVS_FLOW_ATTR_KEY */
664 		+ nla_total_size(key_attr_size()) /* OVS_FLOW_ATTR_MASK */
665 		+ nla_total_size(sizeof(struct ovs_flow_stats)) /* OVS_FLOW_ATTR_STATS */
666 		+ nla_total_size(1) /* OVS_FLOW_ATTR_TCP_FLAGS */
667 		+ nla_total_size(8) /* OVS_FLOW_ATTR_USED */
668 		+ nla_total_size(acts->actions_len); /* OVS_FLOW_ATTR_ACTIONS */
669 }
670 
671 /* Called with ovs_mutex or RCU read lock. */
672 static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
673 				  struct sk_buff *skb, u32 portid,
674 				  u32 seq, u32 flags, u8 cmd)
675 {
676 	const int skb_orig_len = skb->len;
677 	struct nlattr *start;
678 	struct ovs_flow_stats stats;
679 	__be16 tcp_flags;
680 	unsigned long used;
681 	struct ovs_header *ovs_header;
682 	struct nlattr *nla;
683 	int err;
684 
685 	ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family, flags, cmd);
686 	if (!ovs_header)
687 		return -EMSGSIZE;
688 
689 	ovs_header->dp_ifindex = dp_ifindex;
690 
691 	/* Fill flow key. */
692 	nla = nla_nest_start(skb, OVS_FLOW_ATTR_KEY);
693 	if (!nla)
694 		goto nla_put_failure;
695 
696 	err = ovs_nla_put_flow(&flow->unmasked_key, &flow->unmasked_key, skb);
697 	if (err)
698 		goto error;
699 	nla_nest_end(skb, nla);
700 
701 	nla = nla_nest_start(skb, OVS_FLOW_ATTR_MASK);
702 	if (!nla)
703 		goto nla_put_failure;
704 
705 	err = ovs_nla_put_flow(&flow->key, &flow->mask->key, skb);
706 	if (err)
707 		goto error;
708 
709 	nla_nest_end(skb, nla);
710 
711 	ovs_flow_stats_get(flow, &stats, &used, &tcp_flags);
712 
713 	if (used &&
714 	    nla_put_u64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used)))
715 		goto nla_put_failure;
716 
717 	if (stats.n_packets &&
718 	    nla_put(skb, OVS_FLOW_ATTR_STATS, sizeof(struct ovs_flow_stats), &stats))
719 		goto nla_put_failure;
720 
721 	if ((u8)ntohs(tcp_flags) &&
722 	     nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags)))
723 		goto nla_put_failure;
724 
725 	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
726 	 * this is the first flow to be dumped into 'skb'.  This is unusual for
727 	 * Netlink but individual action lists can be longer than
728 	 * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this.
729 	 * The userspace caller can always fetch the actions separately if it
730 	 * really wants them.  (Most userspace callers in fact don't care.)
731 	 *
732 	 * This can only fail for dump operations because the skb is always
733 	 * properly sized for single flows.
734 	 */
735 	start = nla_nest_start(skb, OVS_FLOW_ATTR_ACTIONS);
736 	if (start) {
737 		const struct sw_flow_actions *sf_acts;
738 
739 		sf_acts = rcu_dereference_ovsl(flow->sf_acts);
740 		err = ovs_nla_put_actions(sf_acts->actions,
741 					  sf_acts->actions_len, skb);
742 
743 		if (!err)
744 			nla_nest_end(skb, start);
745 		else {
746 			if (skb_orig_len)
747 				goto error;
748 
749 			nla_nest_cancel(skb, start);
750 		}
751 	} else if (skb_orig_len)
752 		goto nla_put_failure;
753 
754 	return genlmsg_end(skb, ovs_header);
755 
756 nla_put_failure:
757 	err = -EMSGSIZE;
758 error:
759 	genlmsg_cancel(skb, ovs_header);
760 	return err;
761 }
762 
763 /* May not be called with RCU read lock. */
764 static struct sk_buff *ovs_flow_cmd_alloc_info(const struct sw_flow_actions *acts,
765 					       struct genl_info *info,
766 					       bool always)
767 {
768 	struct sk_buff *skb;
769 
770 	if (!always && !ovs_must_notify(&dp_flow_genl_family, info, 0))
771 		return NULL;
772 
773 	skb = genlmsg_new_unicast(ovs_flow_cmd_msg_size(acts), info, GFP_KERNEL);
774 	if (!skb)
775 		return ERR_PTR(-ENOMEM);
776 
777 	return skb;
778 }
779 
780 /* Called with ovs_mutex. */
781 static struct sk_buff *ovs_flow_cmd_build_info(const struct sw_flow *flow,
782 					       int dp_ifindex,
783 					       struct genl_info *info, u8 cmd,
784 					       bool always)
785 {
786 	struct sk_buff *skb;
787 	int retval;
788 
789 	skb = ovs_flow_cmd_alloc_info(ovsl_dereference(flow->sf_acts), info,
790 				      always);
791 	if (IS_ERR_OR_NULL(skb))
792 		return skb;
793 
794 	retval = ovs_flow_cmd_fill_info(flow, dp_ifindex, skb,
795 					info->snd_portid, info->snd_seq, 0,
796 					cmd);
797 	BUG_ON(retval < 0);
798 	return skb;
799 }
800 
801 static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
802 {
803 	struct nlattr **a = info->attrs;
804 	struct ovs_header *ovs_header = info->userhdr;
805 	struct sw_flow *flow, *new_flow;
806 	struct sw_flow_mask mask;
807 	struct sk_buff *reply;
808 	struct datapath *dp;
809 	struct sw_flow_actions *acts;
810 	struct sw_flow_match match;
811 	int error;
812 
813 	/* Must have key and actions. */
814 	error = -EINVAL;
815 	if (!a[OVS_FLOW_ATTR_KEY])
816 		goto error;
817 	if (!a[OVS_FLOW_ATTR_ACTIONS])
818 		goto error;
819 
820 	/* Most of the time we need to allocate a new flow, do it before
821 	 * locking.
822 	 */
823 	new_flow = ovs_flow_alloc();
824 	if (IS_ERR(new_flow)) {
825 		error = PTR_ERR(new_flow);
826 		goto error;
827 	}
828 
829 	/* Extract key. */
830 	ovs_match_init(&match, &new_flow->unmasked_key, &mask);
831 	error = ovs_nla_get_match(&match,
832 				  a[OVS_FLOW_ATTR_KEY], a[OVS_FLOW_ATTR_MASK]);
833 	if (error)
834 		goto err_kfree_flow;
835 
836 	ovs_flow_mask_key(&new_flow->key, &new_flow->unmasked_key, &mask);
837 
838 	/* Validate actions. */
839 	acts = ovs_nla_alloc_flow_actions(nla_len(a[OVS_FLOW_ATTR_ACTIONS]));
840 	error = PTR_ERR(acts);
841 	if (IS_ERR(acts))
842 		goto err_kfree_flow;
843 
844 	error = ovs_nla_copy_actions(a[OVS_FLOW_ATTR_ACTIONS], &new_flow->key,
845 				     0, &acts);
846 	if (error) {
847 		OVS_NLERR("Flow actions may not be safe on all matching packets.\n");
848 		goto err_kfree_acts;
849 	}
850 
851 	reply = ovs_flow_cmd_alloc_info(acts, info, false);
852 	if (IS_ERR(reply)) {
853 		error = PTR_ERR(reply);
854 		goto err_kfree_acts;
855 	}
856 
857 	ovs_lock();
858 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
859 	if (unlikely(!dp)) {
860 		error = -ENODEV;
861 		goto err_unlock_ovs;
862 	}
863 	/* Check if this is a duplicate flow */
864 	flow = ovs_flow_tbl_lookup(&dp->table, &new_flow->unmasked_key);
865 	if (likely(!flow)) {
866 		rcu_assign_pointer(new_flow->sf_acts, acts);
867 
868 		/* Put flow in bucket. */
869 		error = ovs_flow_tbl_insert(&dp->table, new_flow, &mask);
870 		if (unlikely(error)) {
871 			acts = NULL;
872 			goto err_unlock_ovs;
873 		}
874 
875 		if (unlikely(reply)) {
876 			error = ovs_flow_cmd_fill_info(new_flow,
877 						       ovs_header->dp_ifindex,
878 						       reply, info->snd_portid,
879 						       info->snd_seq, 0,
880 						       OVS_FLOW_CMD_NEW);
881 			BUG_ON(error < 0);
882 		}
883 		ovs_unlock();
884 	} else {
885 		struct sw_flow_actions *old_acts;
886 
887 		/* Bail out if we're not allowed to modify an existing flow.
888 		 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
889 		 * because Generic Netlink treats the latter as a dump
890 		 * request.  We also accept NLM_F_EXCL in case that bug ever
891 		 * gets fixed.
892 		 */
893 		if (unlikely(info->nlhdr->nlmsg_flags & (NLM_F_CREATE
894 							 | NLM_F_EXCL))) {
895 			error = -EEXIST;
896 			goto err_unlock_ovs;
897 		}
898 		/* The unmasked key has to be the same for flow updates. */
899 		if (unlikely(!ovs_flow_cmp_unmasked_key(flow, &match))) {
900 			flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
901 			if (!flow) {
902 				error = -ENOENT;
903 				goto err_unlock_ovs;
904 			}
905 		}
906 		/* Update actions. */
907 		old_acts = ovsl_dereference(flow->sf_acts);
908 		rcu_assign_pointer(flow->sf_acts, acts);
909 
910 		if (unlikely(reply)) {
911 			error = ovs_flow_cmd_fill_info(flow,
912 						       ovs_header->dp_ifindex,
913 						       reply, info->snd_portid,
914 						       info->snd_seq, 0,
915 						       OVS_FLOW_CMD_NEW);
916 			BUG_ON(error < 0);
917 		}
918 		ovs_unlock();
919 
920 		ovs_nla_free_flow_actions(old_acts);
921 		ovs_flow_free(new_flow, false);
922 	}
923 
924 	if (reply)
925 		ovs_notify(&dp_flow_genl_family, reply, info);
926 	return 0;
927 
928 err_unlock_ovs:
929 	ovs_unlock();
930 	kfree_skb(reply);
931 err_kfree_acts:
932 	kfree(acts);
933 err_kfree_flow:
934 	ovs_flow_free(new_flow, false);
935 error:
936 	return error;
937 }
938 
939 static struct sw_flow_actions *get_flow_actions(const struct nlattr *a,
940 						const struct sw_flow_key *key,
941 						const struct sw_flow_mask *mask)
942 {
943 	struct sw_flow_actions *acts;
944 	struct sw_flow_key masked_key;
945 	int error;
946 
947 	acts = ovs_nla_alloc_flow_actions(nla_len(a));
948 	if (IS_ERR(acts))
949 		return acts;
950 
951 	ovs_flow_mask_key(&masked_key, key, mask);
952 	error = ovs_nla_copy_actions(a, &masked_key, 0, &acts);
953 	if (error) {
954 		OVS_NLERR("Flow actions may not be safe on all matching packets.\n");
955 		kfree(acts);
956 		return ERR_PTR(error);
957 	}
958 
959 	return acts;
960 }
961 
962 static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
963 {
964 	struct nlattr **a = info->attrs;
965 	struct ovs_header *ovs_header = info->userhdr;
966 	struct sw_flow_key key;
967 	struct sw_flow *flow;
968 	struct sw_flow_mask mask;
969 	struct sk_buff *reply = NULL;
970 	struct datapath *dp;
971 	struct sw_flow_actions *old_acts = NULL, *acts = NULL;
972 	struct sw_flow_match match;
973 	int error;
974 
975 	/* Extract key. */
976 	error = -EINVAL;
977 	if (!a[OVS_FLOW_ATTR_KEY])
978 		goto error;
979 
980 	ovs_match_init(&match, &key, &mask);
981 	error = ovs_nla_get_match(&match,
982 				  a[OVS_FLOW_ATTR_KEY], a[OVS_FLOW_ATTR_MASK]);
983 	if (error)
984 		goto error;
985 
986 	/* Validate actions. */
987 	if (a[OVS_FLOW_ATTR_ACTIONS]) {
988 		acts = get_flow_actions(a[OVS_FLOW_ATTR_ACTIONS], &key, &mask);
989 		if (IS_ERR(acts)) {
990 			error = PTR_ERR(acts);
991 			goto error;
992 		}
993 	}
994 
995 	/* Can allocate before locking if have acts. */
996 	if (acts) {
997 		reply = ovs_flow_cmd_alloc_info(acts, info, false);
998 		if (IS_ERR(reply)) {
999 			error = PTR_ERR(reply);
1000 			goto err_kfree_acts;
1001 		}
1002 	}
1003 
1004 	ovs_lock();
1005 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1006 	if (unlikely(!dp)) {
1007 		error = -ENODEV;
1008 		goto err_unlock_ovs;
1009 	}
1010 	/* Check that the flow exists. */
1011 	flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1012 	if (unlikely(!flow)) {
1013 		error = -ENOENT;
1014 		goto err_unlock_ovs;
1015 	}
1016 
1017 	/* Update actions, if present. */
1018 	if (likely(acts)) {
1019 		old_acts = ovsl_dereference(flow->sf_acts);
1020 		rcu_assign_pointer(flow->sf_acts, acts);
1021 
1022 		if (unlikely(reply)) {
1023 			error = ovs_flow_cmd_fill_info(flow,
1024 						       ovs_header->dp_ifindex,
1025 						       reply, info->snd_portid,
1026 						       info->snd_seq, 0,
1027 						       OVS_FLOW_CMD_NEW);
1028 			BUG_ON(error < 0);
1029 		}
1030 	} else {
1031 		/* Could not alloc without acts before locking. */
1032 		reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex,
1033 						info, OVS_FLOW_CMD_NEW, false);
1034 		if (unlikely(IS_ERR(reply))) {
1035 			error = PTR_ERR(reply);
1036 			goto err_unlock_ovs;
1037 		}
1038 	}
1039 
1040 	/* Clear stats. */
1041 	if (a[OVS_FLOW_ATTR_CLEAR])
1042 		ovs_flow_stats_clear(flow);
1043 	ovs_unlock();
1044 
1045 	if (reply)
1046 		ovs_notify(&dp_flow_genl_family, reply, info);
1047 	if (old_acts)
1048 		ovs_nla_free_flow_actions(old_acts);
1049 
1050 	return 0;
1051 
1052 err_unlock_ovs:
1053 	ovs_unlock();
1054 	kfree_skb(reply);
1055 err_kfree_acts:
1056 	kfree(acts);
1057 error:
1058 	return error;
1059 }
1060 
1061 static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
1062 {
1063 	struct nlattr **a = info->attrs;
1064 	struct ovs_header *ovs_header = info->userhdr;
1065 	struct sw_flow_key key;
1066 	struct sk_buff *reply;
1067 	struct sw_flow *flow;
1068 	struct datapath *dp;
1069 	struct sw_flow_match match;
1070 	int err;
1071 
1072 	if (!a[OVS_FLOW_ATTR_KEY]) {
1073 		OVS_NLERR("Flow get message rejected, Key attribute missing.\n");
1074 		return -EINVAL;
1075 	}
1076 
1077 	ovs_match_init(&match, &key, NULL);
1078 	err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
1079 	if (err)
1080 		return err;
1081 
1082 	ovs_lock();
1083 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1084 	if (!dp) {
1085 		err = -ENODEV;
1086 		goto unlock;
1087 	}
1088 
1089 	flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1090 	if (!flow) {
1091 		err = -ENOENT;
1092 		goto unlock;
1093 	}
1094 
1095 	reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex, info,
1096 					OVS_FLOW_CMD_NEW, true);
1097 	if (IS_ERR(reply)) {
1098 		err = PTR_ERR(reply);
1099 		goto unlock;
1100 	}
1101 
1102 	ovs_unlock();
1103 	return genlmsg_reply(reply, info);
1104 unlock:
1105 	ovs_unlock();
1106 	return err;
1107 }
1108 
1109 static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
1110 {
1111 	struct nlattr **a = info->attrs;
1112 	struct ovs_header *ovs_header = info->userhdr;
1113 	struct sw_flow_key key;
1114 	struct sk_buff *reply;
1115 	struct sw_flow *flow;
1116 	struct datapath *dp;
1117 	struct sw_flow_match match;
1118 	int err;
1119 
1120 	if (likely(a[OVS_FLOW_ATTR_KEY])) {
1121 		ovs_match_init(&match, &key, NULL);
1122 		err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
1123 		if (unlikely(err))
1124 			return err;
1125 	}
1126 
1127 	ovs_lock();
1128 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1129 	if (unlikely(!dp)) {
1130 		err = -ENODEV;
1131 		goto unlock;
1132 	}
1133 
1134 	if (unlikely(!a[OVS_FLOW_ATTR_KEY])) {
1135 		err = ovs_flow_tbl_flush(&dp->table);
1136 		goto unlock;
1137 	}
1138 
1139 	flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1140 	if (unlikely(!flow)) {
1141 		err = -ENOENT;
1142 		goto unlock;
1143 	}
1144 
1145 	ovs_flow_tbl_remove(&dp->table, flow);
1146 	ovs_unlock();
1147 
1148 	reply = ovs_flow_cmd_alloc_info((const struct sw_flow_actions __force *) flow->sf_acts,
1149 					info, false);
1150 	if (likely(reply)) {
1151 		if (likely(!IS_ERR(reply))) {
1152 			rcu_read_lock();	/*To keep RCU checker happy. */
1153 			err = ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex,
1154 						     reply, info->snd_portid,
1155 						     info->snd_seq, 0,
1156 						     OVS_FLOW_CMD_DEL);
1157 			rcu_read_unlock();
1158 			BUG_ON(err < 0);
1159 
1160 			ovs_notify(&dp_flow_genl_family, reply, info);
1161 		} else {
1162 			netlink_set_err(sock_net(skb->sk)->genl_sock, 0, 0, PTR_ERR(reply));
1163 		}
1164 	}
1165 
1166 	ovs_flow_free(flow, true);
1167 	return 0;
1168 unlock:
1169 	ovs_unlock();
1170 	return err;
1171 }
1172 
1173 static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1174 {
1175 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1176 	struct table_instance *ti;
1177 	struct datapath *dp;
1178 
1179 	rcu_read_lock();
1180 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1181 	if (!dp) {
1182 		rcu_read_unlock();
1183 		return -ENODEV;
1184 	}
1185 
1186 	ti = rcu_dereference(dp->table.ti);
1187 	for (;;) {
1188 		struct sw_flow *flow;
1189 		u32 bucket, obj;
1190 
1191 		bucket = cb->args[0];
1192 		obj = cb->args[1];
1193 		flow = ovs_flow_tbl_dump_next(ti, &bucket, &obj);
1194 		if (!flow)
1195 			break;
1196 
1197 		if (ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex, skb,
1198 					   NETLINK_CB(cb->skb).portid,
1199 					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
1200 					   OVS_FLOW_CMD_NEW) < 0)
1201 			break;
1202 
1203 		cb->args[0] = bucket;
1204 		cb->args[1] = obj;
1205 	}
1206 	rcu_read_unlock();
1207 	return skb->len;
1208 }
1209 
1210 static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = {
1211 	[OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED },
1212 	[OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED },
1213 	[OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG },
1214 };
1215 
1216 static const struct genl_ops dp_flow_genl_ops[] = {
1217 	{ .cmd = OVS_FLOW_CMD_NEW,
1218 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1219 	  .policy = flow_policy,
1220 	  .doit = ovs_flow_cmd_new
1221 	},
1222 	{ .cmd = OVS_FLOW_CMD_DEL,
1223 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1224 	  .policy = flow_policy,
1225 	  .doit = ovs_flow_cmd_del
1226 	},
1227 	{ .cmd = OVS_FLOW_CMD_GET,
1228 	  .flags = 0,		    /* OK for unprivileged users. */
1229 	  .policy = flow_policy,
1230 	  .doit = ovs_flow_cmd_get,
1231 	  .dumpit = ovs_flow_cmd_dump
1232 	},
1233 	{ .cmd = OVS_FLOW_CMD_SET,
1234 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1235 	  .policy = flow_policy,
1236 	  .doit = ovs_flow_cmd_set,
1237 	},
1238 };
1239 
1240 static struct genl_family dp_flow_genl_family = {
1241 	.id = GENL_ID_GENERATE,
1242 	.hdrsize = sizeof(struct ovs_header),
1243 	.name = OVS_FLOW_FAMILY,
1244 	.version = OVS_FLOW_VERSION,
1245 	.maxattr = OVS_FLOW_ATTR_MAX,
1246 	.netnsok = true,
1247 	.parallel_ops = true,
1248 	.ops = dp_flow_genl_ops,
1249 	.n_ops = ARRAY_SIZE(dp_flow_genl_ops),
1250 	.mcgrps = &ovs_dp_flow_multicast_group,
1251 	.n_mcgrps = 1,
1252 };
1253 
1254 static size_t ovs_dp_cmd_msg_size(void)
1255 {
1256 	size_t msgsize = NLMSG_ALIGN(sizeof(struct ovs_header));
1257 
1258 	msgsize += nla_total_size(IFNAMSIZ);
1259 	msgsize += nla_total_size(sizeof(struct ovs_dp_stats));
1260 	msgsize += nla_total_size(sizeof(struct ovs_dp_megaflow_stats));
1261 	msgsize += nla_total_size(sizeof(u32)); /* OVS_DP_ATTR_USER_FEATURES */
1262 
1263 	return msgsize;
1264 }
1265 
1266 /* Called with ovs_mutex or RCU read lock. */
1267 static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
1268 				u32 portid, u32 seq, u32 flags, u8 cmd)
1269 {
1270 	struct ovs_header *ovs_header;
1271 	struct ovs_dp_stats dp_stats;
1272 	struct ovs_dp_megaflow_stats dp_megaflow_stats;
1273 	int err;
1274 
1275 	ovs_header = genlmsg_put(skb, portid, seq, &dp_datapath_genl_family,
1276 				   flags, cmd);
1277 	if (!ovs_header)
1278 		goto error;
1279 
1280 	ovs_header->dp_ifindex = get_dpifindex(dp);
1281 
1282 	err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp));
1283 	if (err)
1284 		goto nla_put_failure;
1285 
1286 	get_dp_stats(dp, &dp_stats, &dp_megaflow_stats);
1287 	if (nla_put(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats),
1288 			&dp_stats))
1289 		goto nla_put_failure;
1290 
1291 	if (nla_put(skb, OVS_DP_ATTR_MEGAFLOW_STATS,
1292 			sizeof(struct ovs_dp_megaflow_stats),
1293 			&dp_megaflow_stats))
1294 		goto nla_put_failure;
1295 
1296 	if (nla_put_u32(skb, OVS_DP_ATTR_USER_FEATURES, dp->user_features))
1297 		goto nla_put_failure;
1298 
1299 	return genlmsg_end(skb, ovs_header);
1300 
1301 nla_put_failure:
1302 	genlmsg_cancel(skb, ovs_header);
1303 error:
1304 	return -EMSGSIZE;
1305 }
1306 
1307 static struct sk_buff *ovs_dp_cmd_alloc_info(struct genl_info *info)
1308 {
1309 	return genlmsg_new_unicast(ovs_dp_cmd_msg_size(), info, GFP_KERNEL);
1310 }
1311 
1312 /* Called with rcu_read_lock or ovs_mutex. */
1313 static struct datapath *lookup_datapath(struct net *net,
1314 					struct ovs_header *ovs_header,
1315 					struct nlattr *a[OVS_DP_ATTR_MAX + 1])
1316 {
1317 	struct datapath *dp;
1318 
1319 	if (!a[OVS_DP_ATTR_NAME])
1320 		dp = get_dp(net, ovs_header->dp_ifindex);
1321 	else {
1322 		struct vport *vport;
1323 
1324 		vport = ovs_vport_locate(net, nla_data(a[OVS_DP_ATTR_NAME]));
1325 		dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL;
1326 	}
1327 	return dp ? dp : ERR_PTR(-ENODEV);
1328 }
1329 
1330 static void ovs_dp_reset_user_features(struct sk_buff *skb, struct genl_info *info)
1331 {
1332 	struct datapath *dp;
1333 
1334 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1335 	if (IS_ERR(dp))
1336 		return;
1337 
1338 	WARN(dp->user_features, "Dropping previously announced user features\n");
1339 	dp->user_features = 0;
1340 }
1341 
1342 static void ovs_dp_change(struct datapath *dp, struct nlattr **a)
1343 {
1344 	if (a[OVS_DP_ATTR_USER_FEATURES])
1345 		dp->user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
1346 }
1347 
1348 static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
1349 {
1350 	struct nlattr **a = info->attrs;
1351 	struct vport_parms parms;
1352 	struct sk_buff *reply;
1353 	struct datapath *dp;
1354 	struct vport *vport;
1355 	struct ovs_net *ovs_net;
1356 	int err, i;
1357 
1358 	err = -EINVAL;
1359 	if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
1360 		goto err;
1361 
1362 	reply = ovs_dp_cmd_alloc_info(info);
1363 	if (!reply)
1364 		return -ENOMEM;
1365 
1366 	err = -ENOMEM;
1367 	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
1368 	if (dp == NULL)
1369 		goto err_free_reply;
1370 
1371 	ovs_dp_set_net(dp, hold_net(sock_net(skb->sk)));
1372 
1373 	/* Allocate table. */
1374 	err = ovs_flow_tbl_init(&dp->table);
1375 	if (err)
1376 		goto err_free_dp;
1377 
1378 	dp->stats_percpu = netdev_alloc_pcpu_stats(struct dp_stats_percpu);
1379 	if (!dp->stats_percpu) {
1380 		err = -ENOMEM;
1381 		goto err_destroy_table;
1382 	}
1383 
1384 	dp->ports = kmalloc(DP_VPORT_HASH_BUCKETS * sizeof(struct hlist_head),
1385 			    GFP_KERNEL);
1386 	if (!dp->ports) {
1387 		err = -ENOMEM;
1388 		goto err_destroy_percpu;
1389 	}
1390 
1391 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
1392 		INIT_HLIST_HEAD(&dp->ports[i]);
1393 
1394 	/* Set up our datapath device. */
1395 	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
1396 	parms.type = OVS_VPORT_TYPE_INTERNAL;
1397 	parms.options = NULL;
1398 	parms.dp = dp;
1399 	parms.port_no = OVSP_LOCAL;
1400 	parms.upcall_portids = a[OVS_DP_ATTR_UPCALL_PID];
1401 
1402 	ovs_dp_change(dp, a);
1403 
1404 	/* So far only local changes have been made, now need the lock. */
1405 	ovs_lock();
1406 
1407 	vport = new_vport(&parms);
1408 	if (IS_ERR(vport)) {
1409 		err = PTR_ERR(vport);
1410 		if (err == -EBUSY)
1411 			err = -EEXIST;
1412 
1413 		if (err == -EEXIST) {
1414 			/* An outdated user space instance that does not understand
1415 			 * the concept of user_features has attempted to create a new
1416 			 * datapath and is likely to reuse it. Drop all user features.
1417 			 */
1418 			if (info->genlhdr->version < OVS_DP_VER_FEATURES)
1419 				ovs_dp_reset_user_features(skb, info);
1420 		}
1421 
1422 		goto err_destroy_ports_array;
1423 	}
1424 
1425 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1426 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1427 	BUG_ON(err < 0);
1428 
1429 	ovs_net = net_generic(ovs_dp_get_net(dp), ovs_net_id);
1430 	list_add_tail_rcu(&dp->list_node, &ovs_net->dps);
1431 
1432 	ovs_unlock();
1433 
1434 	ovs_notify(&dp_datapath_genl_family, reply, info);
1435 	return 0;
1436 
1437 err_destroy_ports_array:
1438 	ovs_unlock();
1439 	kfree(dp->ports);
1440 err_destroy_percpu:
1441 	free_percpu(dp->stats_percpu);
1442 err_destroy_table:
1443 	ovs_flow_tbl_destroy(&dp->table, false);
1444 err_free_dp:
1445 	release_net(ovs_dp_get_net(dp));
1446 	kfree(dp);
1447 err_free_reply:
1448 	kfree_skb(reply);
1449 err:
1450 	return err;
1451 }
1452 
1453 /* Called with ovs_mutex. */
1454 static void __dp_destroy(struct datapath *dp)
1455 {
1456 	int i;
1457 
1458 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
1459 		struct vport *vport;
1460 		struct hlist_node *n;
1461 
1462 		hlist_for_each_entry_safe(vport, n, &dp->ports[i], dp_hash_node)
1463 			if (vport->port_no != OVSP_LOCAL)
1464 				ovs_dp_detach_port(vport);
1465 	}
1466 
1467 	list_del_rcu(&dp->list_node);
1468 
1469 	/* OVSP_LOCAL is datapath internal port. We need to make sure that
1470 	 * all ports in datapath are destroyed first before freeing datapath.
1471 	 */
1472 	ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
1473 
1474 	/* RCU destroy the flow table */
1475 	ovs_flow_tbl_destroy(&dp->table, true);
1476 
1477 	call_rcu(&dp->rcu, destroy_dp_rcu);
1478 }
1479 
1480 static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
1481 {
1482 	struct sk_buff *reply;
1483 	struct datapath *dp;
1484 	int err;
1485 
1486 	reply = ovs_dp_cmd_alloc_info(info);
1487 	if (!reply)
1488 		return -ENOMEM;
1489 
1490 	ovs_lock();
1491 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1492 	err = PTR_ERR(dp);
1493 	if (IS_ERR(dp))
1494 		goto err_unlock_free;
1495 
1496 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1497 				   info->snd_seq, 0, OVS_DP_CMD_DEL);
1498 	BUG_ON(err < 0);
1499 
1500 	__dp_destroy(dp);
1501 	ovs_unlock();
1502 
1503 	ovs_notify(&dp_datapath_genl_family, reply, info);
1504 
1505 	return 0;
1506 
1507 err_unlock_free:
1508 	ovs_unlock();
1509 	kfree_skb(reply);
1510 	return err;
1511 }
1512 
1513 static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
1514 {
1515 	struct sk_buff *reply;
1516 	struct datapath *dp;
1517 	int err;
1518 
1519 	reply = ovs_dp_cmd_alloc_info(info);
1520 	if (!reply)
1521 		return -ENOMEM;
1522 
1523 	ovs_lock();
1524 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1525 	err = PTR_ERR(dp);
1526 	if (IS_ERR(dp))
1527 		goto err_unlock_free;
1528 
1529 	ovs_dp_change(dp, info->attrs);
1530 
1531 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1532 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1533 	BUG_ON(err < 0);
1534 
1535 	ovs_unlock();
1536 	ovs_notify(&dp_datapath_genl_family, reply, info);
1537 
1538 	return 0;
1539 
1540 err_unlock_free:
1541 	ovs_unlock();
1542 	kfree_skb(reply);
1543 	return err;
1544 }
1545 
1546 static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
1547 {
1548 	struct sk_buff *reply;
1549 	struct datapath *dp;
1550 	int err;
1551 
1552 	reply = ovs_dp_cmd_alloc_info(info);
1553 	if (!reply)
1554 		return -ENOMEM;
1555 
1556 	rcu_read_lock();
1557 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1558 	if (IS_ERR(dp)) {
1559 		err = PTR_ERR(dp);
1560 		goto err_unlock_free;
1561 	}
1562 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1563 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1564 	BUG_ON(err < 0);
1565 	rcu_read_unlock();
1566 
1567 	return genlmsg_reply(reply, info);
1568 
1569 err_unlock_free:
1570 	rcu_read_unlock();
1571 	kfree_skb(reply);
1572 	return err;
1573 }
1574 
1575 static int ovs_dp_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1576 {
1577 	struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
1578 	struct datapath *dp;
1579 	int skip = cb->args[0];
1580 	int i = 0;
1581 
1582 	rcu_read_lock();
1583 	list_for_each_entry_rcu(dp, &ovs_net->dps, list_node) {
1584 		if (i >= skip &&
1585 		    ovs_dp_cmd_fill_info(dp, skb, NETLINK_CB(cb->skb).portid,
1586 					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1587 					 OVS_DP_CMD_NEW) < 0)
1588 			break;
1589 		i++;
1590 	}
1591 	rcu_read_unlock();
1592 
1593 	cb->args[0] = i;
1594 
1595 	return skb->len;
1596 }
1597 
1598 static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
1599 	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1600 	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1601 	[OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 },
1602 };
1603 
1604 static const struct genl_ops dp_datapath_genl_ops[] = {
1605 	{ .cmd = OVS_DP_CMD_NEW,
1606 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1607 	  .policy = datapath_policy,
1608 	  .doit = ovs_dp_cmd_new
1609 	},
1610 	{ .cmd = OVS_DP_CMD_DEL,
1611 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1612 	  .policy = datapath_policy,
1613 	  .doit = ovs_dp_cmd_del
1614 	},
1615 	{ .cmd = OVS_DP_CMD_GET,
1616 	  .flags = 0,		    /* OK for unprivileged users. */
1617 	  .policy = datapath_policy,
1618 	  .doit = ovs_dp_cmd_get,
1619 	  .dumpit = ovs_dp_cmd_dump
1620 	},
1621 	{ .cmd = OVS_DP_CMD_SET,
1622 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1623 	  .policy = datapath_policy,
1624 	  .doit = ovs_dp_cmd_set,
1625 	},
1626 };
1627 
1628 static struct genl_family dp_datapath_genl_family = {
1629 	.id = GENL_ID_GENERATE,
1630 	.hdrsize = sizeof(struct ovs_header),
1631 	.name = OVS_DATAPATH_FAMILY,
1632 	.version = OVS_DATAPATH_VERSION,
1633 	.maxattr = OVS_DP_ATTR_MAX,
1634 	.netnsok = true,
1635 	.parallel_ops = true,
1636 	.ops = dp_datapath_genl_ops,
1637 	.n_ops = ARRAY_SIZE(dp_datapath_genl_ops),
1638 	.mcgrps = &ovs_dp_datapath_multicast_group,
1639 	.n_mcgrps = 1,
1640 };
1641 
1642 /* Called with ovs_mutex or RCU read lock. */
1643 static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
1644 				   u32 portid, u32 seq, u32 flags, u8 cmd)
1645 {
1646 	struct ovs_header *ovs_header;
1647 	struct ovs_vport_stats vport_stats;
1648 	int err;
1649 
1650 	ovs_header = genlmsg_put(skb, portid, seq, &dp_vport_genl_family,
1651 				 flags, cmd);
1652 	if (!ovs_header)
1653 		return -EMSGSIZE;
1654 
1655 	ovs_header->dp_ifindex = get_dpifindex(vport->dp);
1656 
1657 	if (nla_put_u32(skb, OVS_VPORT_ATTR_PORT_NO, vport->port_no) ||
1658 	    nla_put_u32(skb, OVS_VPORT_ATTR_TYPE, vport->ops->type) ||
1659 	    nla_put_string(skb, OVS_VPORT_ATTR_NAME,
1660 			   vport->ops->get_name(vport)))
1661 		goto nla_put_failure;
1662 
1663 	ovs_vport_get_stats(vport, &vport_stats);
1664 	if (nla_put(skb, OVS_VPORT_ATTR_STATS, sizeof(struct ovs_vport_stats),
1665 		    &vport_stats))
1666 		goto nla_put_failure;
1667 
1668 	if (ovs_vport_get_upcall_portids(vport, skb))
1669 		goto nla_put_failure;
1670 
1671 	err = ovs_vport_get_options(vport, skb);
1672 	if (err == -EMSGSIZE)
1673 		goto error;
1674 
1675 	return genlmsg_end(skb, ovs_header);
1676 
1677 nla_put_failure:
1678 	err = -EMSGSIZE;
1679 error:
1680 	genlmsg_cancel(skb, ovs_header);
1681 	return err;
1682 }
1683 
1684 static struct sk_buff *ovs_vport_cmd_alloc_info(void)
1685 {
1686 	return nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1687 }
1688 
1689 /* Called with ovs_mutex, only via ovs_dp_notify_wq(). */
1690 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, u32 portid,
1691 					 u32 seq, u8 cmd)
1692 {
1693 	struct sk_buff *skb;
1694 	int retval;
1695 
1696 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1697 	if (!skb)
1698 		return ERR_PTR(-ENOMEM);
1699 
1700 	retval = ovs_vport_cmd_fill_info(vport, skb, portid, seq, 0, cmd);
1701 	BUG_ON(retval < 0);
1702 
1703 	return skb;
1704 }
1705 
1706 /* Called with ovs_mutex or RCU read lock. */
1707 static struct vport *lookup_vport(struct net *net,
1708 				  struct ovs_header *ovs_header,
1709 				  struct nlattr *a[OVS_VPORT_ATTR_MAX + 1])
1710 {
1711 	struct datapath *dp;
1712 	struct vport *vport;
1713 
1714 	if (a[OVS_VPORT_ATTR_NAME]) {
1715 		vport = ovs_vport_locate(net, nla_data(a[OVS_VPORT_ATTR_NAME]));
1716 		if (!vport)
1717 			return ERR_PTR(-ENODEV);
1718 		if (ovs_header->dp_ifindex &&
1719 		    ovs_header->dp_ifindex != get_dpifindex(vport->dp))
1720 			return ERR_PTR(-ENODEV);
1721 		return vport;
1722 	} else if (a[OVS_VPORT_ATTR_PORT_NO]) {
1723 		u32 port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
1724 
1725 		if (port_no >= DP_MAX_PORTS)
1726 			return ERR_PTR(-EFBIG);
1727 
1728 		dp = get_dp(net, ovs_header->dp_ifindex);
1729 		if (!dp)
1730 			return ERR_PTR(-ENODEV);
1731 
1732 		vport = ovs_vport_ovsl_rcu(dp, port_no);
1733 		if (!vport)
1734 			return ERR_PTR(-ENODEV);
1735 		return vport;
1736 	} else
1737 		return ERR_PTR(-EINVAL);
1738 }
1739 
1740 static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
1741 {
1742 	struct nlattr **a = info->attrs;
1743 	struct ovs_header *ovs_header = info->userhdr;
1744 	struct vport_parms parms;
1745 	struct sk_buff *reply;
1746 	struct vport *vport;
1747 	struct datapath *dp;
1748 	u32 port_no;
1749 	int err;
1750 
1751 	if (!a[OVS_VPORT_ATTR_NAME] || !a[OVS_VPORT_ATTR_TYPE] ||
1752 	    !a[OVS_VPORT_ATTR_UPCALL_PID])
1753 		return -EINVAL;
1754 
1755 	port_no = a[OVS_VPORT_ATTR_PORT_NO]
1756 		? nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]) : 0;
1757 	if (port_no >= DP_MAX_PORTS)
1758 		return -EFBIG;
1759 
1760 	reply = ovs_vport_cmd_alloc_info();
1761 	if (!reply)
1762 		return -ENOMEM;
1763 
1764 	ovs_lock();
1765 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1766 	err = -ENODEV;
1767 	if (!dp)
1768 		goto exit_unlock_free;
1769 
1770 	if (port_no) {
1771 		vport = ovs_vport_ovsl(dp, port_no);
1772 		err = -EBUSY;
1773 		if (vport)
1774 			goto exit_unlock_free;
1775 	} else {
1776 		for (port_no = 1; ; port_no++) {
1777 			if (port_no >= DP_MAX_PORTS) {
1778 				err = -EFBIG;
1779 				goto exit_unlock_free;
1780 			}
1781 			vport = ovs_vport_ovsl(dp, port_no);
1782 			if (!vport)
1783 				break;
1784 		}
1785 	}
1786 
1787 	parms.name = nla_data(a[OVS_VPORT_ATTR_NAME]);
1788 	parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
1789 	parms.options = a[OVS_VPORT_ATTR_OPTIONS];
1790 	parms.dp = dp;
1791 	parms.port_no = port_no;
1792 	parms.upcall_portids = a[OVS_VPORT_ATTR_UPCALL_PID];
1793 
1794 	vport = new_vport(&parms);
1795 	err = PTR_ERR(vport);
1796 	if (IS_ERR(vport))
1797 		goto exit_unlock_free;
1798 
1799 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1800 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
1801 	BUG_ON(err < 0);
1802 	ovs_unlock();
1803 
1804 	ovs_notify(&dp_vport_genl_family, reply, info);
1805 	return 0;
1806 
1807 exit_unlock_free:
1808 	ovs_unlock();
1809 	kfree_skb(reply);
1810 	return err;
1811 }
1812 
1813 static int ovs_vport_cmd_set(struct sk_buff *skb, struct genl_info *info)
1814 {
1815 	struct nlattr **a = info->attrs;
1816 	struct sk_buff *reply;
1817 	struct vport *vport;
1818 	int err;
1819 
1820 	reply = ovs_vport_cmd_alloc_info();
1821 	if (!reply)
1822 		return -ENOMEM;
1823 
1824 	ovs_lock();
1825 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
1826 	err = PTR_ERR(vport);
1827 	if (IS_ERR(vport))
1828 		goto exit_unlock_free;
1829 
1830 	if (a[OVS_VPORT_ATTR_TYPE] &&
1831 	    nla_get_u32(a[OVS_VPORT_ATTR_TYPE]) != vport->ops->type) {
1832 		err = -EINVAL;
1833 		goto exit_unlock_free;
1834 	}
1835 
1836 	if (a[OVS_VPORT_ATTR_OPTIONS]) {
1837 		err = ovs_vport_set_options(vport, a[OVS_VPORT_ATTR_OPTIONS]);
1838 		if (err)
1839 			goto exit_unlock_free;
1840 	}
1841 
1842 
1843 	if (a[OVS_VPORT_ATTR_UPCALL_PID]) {
1844 		struct nlattr *ids = a[OVS_VPORT_ATTR_UPCALL_PID];
1845 
1846 		err = ovs_vport_set_upcall_portids(vport, ids);
1847 		if (err)
1848 			goto exit_unlock_free;
1849 	}
1850 
1851 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1852 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
1853 	BUG_ON(err < 0);
1854 
1855 	ovs_unlock();
1856 	ovs_notify(&dp_vport_genl_family, reply, info);
1857 	return 0;
1858 
1859 exit_unlock_free:
1860 	ovs_unlock();
1861 	kfree_skb(reply);
1862 	return err;
1863 }
1864 
1865 static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info)
1866 {
1867 	struct nlattr **a = info->attrs;
1868 	struct sk_buff *reply;
1869 	struct vport *vport;
1870 	int err;
1871 
1872 	reply = ovs_vport_cmd_alloc_info();
1873 	if (!reply)
1874 		return -ENOMEM;
1875 
1876 	ovs_lock();
1877 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
1878 	err = PTR_ERR(vport);
1879 	if (IS_ERR(vport))
1880 		goto exit_unlock_free;
1881 
1882 	if (vport->port_no == OVSP_LOCAL) {
1883 		err = -EINVAL;
1884 		goto exit_unlock_free;
1885 	}
1886 
1887 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1888 				      info->snd_seq, 0, OVS_VPORT_CMD_DEL);
1889 	BUG_ON(err < 0);
1890 	ovs_dp_detach_port(vport);
1891 	ovs_unlock();
1892 
1893 	ovs_notify(&dp_vport_genl_family, reply, info);
1894 	return 0;
1895 
1896 exit_unlock_free:
1897 	ovs_unlock();
1898 	kfree_skb(reply);
1899 	return err;
1900 }
1901 
1902 static int ovs_vport_cmd_get(struct sk_buff *skb, struct genl_info *info)
1903 {
1904 	struct nlattr **a = info->attrs;
1905 	struct ovs_header *ovs_header = info->userhdr;
1906 	struct sk_buff *reply;
1907 	struct vport *vport;
1908 	int err;
1909 
1910 	reply = ovs_vport_cmd_alloc_info();
1911 	if (!reply)
1912 		return -ENOMEM;
1913 
1914 	rcu_read_lock();
1915 	vport = lookup_vport(sock_net(skb->sk), ovs_header, a);
1916 	err = PTR_ERR(vport);
1917 	if (IS_ERR(vport))
1918 		goto exit_unlock_free;
1919 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1920 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
1921 	BUG_ON(err < 0);
1922 	rcu_read_unlock();
1923 
1924 	return genlmsg_reply(reply, info);
1925 
1926 exit_unlock_free:
1927 	rcu_read_unlock();
1928 	kfree_skb(reply);
1929 	return err;
1930 }
1931 
1932 static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1933 {
1934 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1935 	struct datapath *dp;
1936 	int bucket = cb->args[0], skip = cb->args[1];
1937 	int i, j = 0;
1938 
1939 	rcu_read_lock();
1940 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1941 	if (!dp) {
1942 		rcu_read_unlock();
1943 		return -ENODEV;
1944 	}
1945 	for (i = bucket; i < DP_VPORT_HASH_BUCKETS; i++) {
1946 		struct vport *vport;
1947 
1948 		j = 0;
1949 		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) {
1950 			if (j >= skip &&
1951 			    ovs_vport_cmd_fill_info(vport, skb,
1952 						    NETLINK_CB(cb->skb).portid,
1953 						    cb->nlh->nlmsg_seq,
1954 						    NLM_F_MULTI,
1955 						    OVS_VPORT_CMD_NEW) < 0)
1956 				goto out;
1957 
1958 			j++;
1959 		}
1960 		skip = 0;
1961 	}
1962 out:
1963 	rcu_read_unlock();
1964 
1965 	cb->args[0] = i;
1966 	cb->args[1] = j;
1967 
1968 	return skb->len;
1969 }
1970 
1971 static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
1972 	[OVS_VPORT_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1973 	[OVS_VPORT_ATTR_STATS] = { .len = sizeof(struct ovs_vport_stats) },
1974 	[OVS_VPORT_ATTR_PORT_NO] = { .type = NLA_U32 },
1975 	[OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 },
1976 	[OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1977 	[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
1978 };
1979 
1980 static const struct genl_ops dp_vport_genl_ops[] = {
1981 	{ .cmd = OVS_VPORT_CMD_NEW,
1982 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1983 	  .policy = vport_policy,
1984 	  .doit = ovs_vport_cmd_new
1985 	},
1986 	{ .cmd = OVS_VPORT_CMD_DEL,
1987 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1988 	  .policy = vport_policy,
1989 	  .doit = ovs_vport_cmd_del
1990 	},
1991 	{ .cmd = OVS_VPORT_CMD_GET,
1992 	  .flags = 0,		    /* OK for unprivileged users. */
1993 	  .policy = vport_policy,
1994 	  .doit = ovs_vport_cmd_get,
1995 	  .dumpit = ovs_vport_cmd_dump
1996 	},
1997 	{ .cmd = OVS_VPORT_CMD_SET,
1998 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1999 	  .policy = vport_policy,
2000 	  .doit = ovs_vport_cmd_set,
2001 	},
2002 };
2003 
2004 struct genl_family dp_vport_genl_family = {
2005 	.id = GENL_ID_GENERATE,
2006 	.hdrsize = sizeof(struct ovs_header),
2007 	.name = OVS_VPORT_FAMILY,
2008 	.version = OVS_VPORT_VERSION,
2009 	.maxattr = OVS_VPORT_ATTR_MAX,
2010 	.netnsok = true,
2011 	.parallel_ops = true,
2012 	.ops = dp_vport_genl_ops,
2013 	.n_ops = ARRAY_SIZE(dp_vport_genl_ops),
2014 	.mcgrps = &ovs_dp_vport_multicast_group,
2015 	.n_mcgrps = 1,
2016 };
2017 
2018 static struct genl_family * const dp_genl_families[] = {
2019 	&dp_datapath_genl_family,
2020 	&dp_vport_genl_family,
2021 	&dp_flow_genl_family,
2022 	&dp_packet_genl_family,
2023 };
2024 
2025 static void dp_unregister_genl(int n_families)
2026 {
2027 	int i;
2028 
2029 	for (i = 0; i < n_families; i++)
2030 		genl_unregister_family(dp_genl_families[i]);
2031 }
2032 
2033 static int dp_register_genl(void)
2034 {
2035 	int err;
2036 	int i;
2037 
2038 	for (i = 0; i < ARRAY_SIZE(dp_genl_families); i++) {
2039 
2040 		err = genl_register_family(dp_genl_families[i]);
2041 		if (err)
2042 			goto error;
2043 	}
2044 
2045 	return 0;
2046 
2047 error:
2048 	dp_unregister_genl(i);
2049 	return err;
2050 }
2051 
2052 static int __net_init ovs_init_net(struct net *net)
2053 {
2054 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2055 
2056 	INIT_LIST_HEAD(&ovs_net->dps);
2057 	INIT_WORK(&ovs_net->dp_notify_work, ovs_dp_notify_wq);
2058 	return 0;
2059 }
2060 
2061 static void __net_exit ovs_exit_net(struct net *net)
2062 {
2063 	struct datapath *dp, *dp_next;
2064 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2065 
2066 	ovs_lock();
2067 	list_for_each_entry_safe(dp, dp_next, &ovs_net->dps, list_node)
2068 		__dp_destroy(dp);
2069 	ovs_unlock();
2070 
2071 	cancel_work_sync(&ovs_net->dp_notify_work);
2072 }
2073 
2074 static struct pernet_operations ovs_net_ops = {
2075 	.init = ovs_init_net,
2076 	.exit = ovs_exit_net,
2077 	.id   = &ovs_net_id,
2078 	.size = sizeof(struct ovs_net),
2079 };
2080 
2081 static int __init dp_init(void)
2082 {
2083 	int err;
2084 
2085 	BUILD_BUG_ON(sizeof(struct ovs_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb));
2086 
2087 	pr_info("Open vSwitch switching datapath\n");
2088 
2089 	err = action_fifos_init();
2090 	if (err)
2091 		goto error;
2092 
2093 	err = ovs_internal_dev_rtnl_link_register();
2094 	if (err)
2095 		goto error_action_fifos_exit;
2096 
2097 	err = ovs_flow_init();
2098 	if (err)
2099 		goto error_unreg_rtnl_link;
2100 
2101 	err = ovs_vport_init();
2102 	if (err)
2103 		goto error_flow_exit;
2104 
2105 	err = register_pernet_device(&ovs_net_ops);
2106 	if (err)
2107 		goto error_vport_exit;
2108 
2109 	err = register_netdevice_notifier(&ovs_dp_device_notifier);
2110 	if (err)
2111 		goto error_netns_exit;
2112 
2113 	err = dp_register_genl();
2114 	if (err < 0)
2115 		goto error_unreg_notifier;
2116 
2117 	return 0;
2118 
2119 error_unreg_notifier:
2120 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2121 error_netns_exit:
2122 	unregister_pernet_device(&ovs_net_ops);
2123 error_vport_exit:
2124 	ovs_vport_exit();
2125 error_flow_exit:
2126 	ovs_flow_exit();
2127 error_unreg_rtnl_link:
2128 	ovs_internal_dev_rtnl_link_unregister();
2129 error_action_fifos_exit:
2130 	action_fifos_exit();
2131 error:
2132 	return err;
2133 }
2134 
2135 static void dp_cleanup(void)
2136 {
2137 	dp_unregister_genl(ARRAY_SIZE(dp_genl_families));
2138 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2139 	unregister_pernet_device(&ovs_net_ops);
2140 	rcu_barrier();
2141 	ovs_vport_exit();
2142 	ovs_flow_exit();
2143 	ovs_internal_dev_rtnl_link_unregister();
2144 	action_fifos_exit();
2145 }
2146 
2147 module_init(dp_init);
2148 module_exit(dp_cleanup);
2149 
2150 MODULE_DESCRIPTION("Open vSwitch switching datapath");
2151 MODULE_LICENSE("GPL");
2152