xref: /openbmc/linux/net/openvswitch/datapath.c (revision 4ae555a5)
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 EXPORT_SYMBOL_GPL(ovs_net_id);
63 
64 static struct genl_family dp_packet_genl_family;
65 static struct genl_family dp_flow_genl_family;
66 static struct genl_family dp_datapath_genl_family;
67 
68 static const struct nla_policy flow_policy[];
69 
70 static const struct genl_multicast_group ovs_dp_flow_multicast_group = {
71 	.name = OVS_FLOW_MCGROUP,
72 };
73 
74 static const struct genl_multicast_group ovs_dp_datapath_multicast_group = {
75 	.name = OVS_DATAPATH_MCGROUP,
76 };
77 
78 static const struct genl_multicast_group ovs_dp_vport_multicast_group = {
79 	.name = OVS_VPORT_MCGROUP,
80 };
81 
82 /* Check if need to build a reply message.
83  * OVS userspace sets the NLM_F_ECHO flag if it needs the reply. */
84 static bool ovs_must_notify(struct genl_family *family, struct genl_info *info,
85 			    unsigned int group)
86 {
87 	return info->nlhdr->nlmsg_flags & NLM_F_ECHO ||
88 	       genl_has_listeners(family, genl_info_net(info), group);
89 }
90 
91 static void ovs_notify(struct genl_family *family,
92 		       struct sk_buff *skb, struct genl_info *info)
93 {
94 	genl_notify(family, skb, genl_info_net(info), info->snd_portid,
95 		    0, info->nlhdr, GFP_KERNEL);
96 }
97 
98 /**
99  * DOC: Locking:
100  *
101  * All writes e.g. Writes to device state (add/remove datapath, port, set
102  * operations on vports, etc.), Writes to other state (flow table
103  * modifications, set miscellaneous datapath parameters, etc.) are protected
104  * by ovs_lock.
105  *
106  * Reads are protected by RCU.
107  *
108  * There are a few special cases (mostly stats) that have their own
109  * synchronization but they nest under all of above and don't interact with
110  * each other.
111  *
112  * The RTNL lock nests inside ovs_mutex.
113  */
114 
115 static DEFINE_MUTEX(ovs_mutex);
116 
117 void ovs_lock(void)
118 {
119 	mutex_lock(&ovs_mutex);
120 }
121 
122 void ovs_unlock(void)
123 {
124 	mutex_unlock(&ovs_mutex);
125 }
126 
127 #ifdef CONFIG_LOCKDEP
128 int lockdep_ovsl_is_held(void)
129 {
130 	if (debug_locks)
131 		return lockdep_is_held(&ovs_mutex);
132 	else
133 		return 1;
134 }
135 EXPORT_SYMBOL_GPL(lockdep_ovsl_is_held);
136 #endif
137 
138 static struct vport *new_vport(const struct vport_parms *);
139 static int queue_gso_packets(struct datapath *dp, struct sk_buff *,
140 			     const struct sw_flow_key *,
141 			     const struct dp_upcall_info *);
142 static int queue_userspace_packet(struct datapath *dp, struct sk_buff *,
143 				  const struct sw_flow_key *,
144 				  const struct dp_upcall_info *);
145 
146 /* Must be called with rcu_read_lock. */
147 static struct datapath *get_dp_rcu(struct net *net, int dp_ifindex)
148 {
149 	struct net_device *dev = dev_get_by_index_rcu(net, dp_ifindex);
150 
151 	if (dev) {
152 		struct vport *vport = ovs_internal_dev_get_vport(dev);
153 		if (vport)
154 			return vport->dp;
155 	}
156 
157 	return NULL;
158 }
159 
160 /* The caller must hold either ovs_mutex or rcu_read_lock to keep the
161  * returned dp pointer valid.
162  */
163 static inline struct datapath *get_dp(struct net *net, int dp_ifindex)
164 {
165 	struct datapath *dp;
166 
167 	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held());
168 	rcu_read_lock();
169 	dp = get_dp_rcu(net, dp_ifindex);
170 	rcu_read_unlock();
171 
172 	return dp;
173 }
174 
175 /* Must be called with rcu_read_lock or ovs_mutex. */
176 const char *ovs_dp_name(const struct datapath *dp)
177 {
178 	struct vport *vport = ovs_vport_ovsl_rcu(dp, OVSP_LOCAL);
179 	return vport->ops->get_name(vport);
180 }
181 
182 static int get_dpifindex(const struct datapath *dp)
183 {
184 	struct vport *local;
185 	int ifindex;
186 
187 	rcu_read_lock();
188 
189 	local = ovs_vport_rcu(dp, OVSP_LOCAL);
190 	if (local)
191 		ifindex = netdev_vport_priv(local)->dev->ifindex;
192 	else
193 		ifindex = 0;
194 
195 	rcu_read_unlock();
196 
197 	return ifindex;
198 }
199 
200 static void destroy_dp_rcu(struct rcu_head *rcu)
201 {
202 	struct datapath *dp = container_of(rcu, struct datapath, rcu);
203 
204 	ovs_flow_tbl_destroy(&dp->table);
205 	free_percpu(dp->stats_percpu);
206 	kfree(dp->ports);
207 	kfree(dp);
208 }
209 
210 static struct hlist_head *vport_hash_bucket(const struct datapath *dp,
211 					    u16 port_no)
212 {
213 	return &dp->ports[port_no & (DP_VPORT_HASH_BUCKETS - 1)];
214 }
215 
216 /* Called with ovs_mutex or RCU read lock. */
217 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no)
218 {
219 	struct vport *vport;
220 	struct hlist_head *head;
221 
222 	head = vport_hash_bucket(dp, port_no);
223 	hlist_for_each_entry_rcu(vport, head, dp_hash_node) {
224 		if (vport->port_no == port_no)
225 			return vport;
226 	}
227 	return NULL;
228 }
229 
230 /* Called with ovs_mutex. */
231 static struct vport *new_vport(const struct vport_parms *parms)
232 {
233 	struct vport *vport;
234 
235 	vport = ovs_vport_add(parms);
236 	if (!IS_ERR(vport)) {
237 		struct datapath *dp = parms->dp;
238 		struct hlist_head *head = vport_hash_bucket(dp, vport->port_no);
239 
240 		hlist_add_head_rcu(&vport->dp_hash_node, head);
241 	}
242 	return vport;
243 }
244 
245 void ovs_dp_detach_port(struct vport *p)
246 {
247 	ASSERT_OVSL();
248 
249 	/* First drop references to device. */
250 	hlist_del_rcu(&p->dp_hash_node);
251 
252 	/* Then destroy it. */
253 	ovs_vport_del(p);
254 }
255 
256 /* Must be called with rcu_read_lock. */
257 void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key)
258 {
259 	const struct vport *p = OVS_CB(skb)->input_vport;
260 	struct datapath *dp = p->dp;
261 	struct sw_flow *flow;
262 	struct sw_flow_actions *sf_acts;
263 	struct dp_stats_percpu *stats;
264 	u64 *stats_counter;
265 	u32 n_mask_hit;
266 
267 	stats = this_cpu_ptr(dp->stats_percpu);
268 
269 	/* Look up flow. */
270 	flow = ovs_flow_tbl_lookup_stats(&dp->table, key, &n_mask_hit);
271 	if (unlikely(!flow)) {
272 		struct dp_upcall_info upcall;
273 		int error;
274 
275 		memset(&upcall, 0, sizeof(upcall));
276 		upcall.cmd = OVS_PACKET_CMD_MISS;
277 		upcall.portid = ovs_vport_find_upcall_portid(p, skb);
278 		error = ovs_dp_upcall(dp, skb, key, &upcall);
279 		if (unlikely(error))
280 			kfree_skb(skb);
281 		else
282 			consume_skb(skb);
283 		stats_counter = &stats->n_missed;
284 		goto out;
285 	}
286 
287 	ovs_flow_stats_update(flow, key->tp.flags, skb);
288 	sf_acts = rcu_dereference(flow->sf_acts);
289 	ovs_execute_actions(dp, skb, sf_acts, key);
290 
291 	stats_counter = &stats->n_hit;
292 
293 out:
294 	/* Update datapath statistics. */
295 	u64_stats_update_begin(&stats->syncp);
296 	(*stats_counter)++;
297 	stats->n_mask_hit += n_mask_hit;
298 	u64_stats_update_end(&stats->syncp);
299 }
300 
301 int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
302 		  const struct sw_flow_key *key,
303 		  const struct dp_upcall_info *upcall_info)
304 {
305 	struct dp_stats_percpu *stats;
306 	int err;
307 
308 	if (upcall_info->portid == 0) {
309 		err = -ENOTCONN;
310 		goto err;
311 	}
312 
313 	if (!skb_is_gso(skb))
314 		err = queue_userspace_packet(dp, skb, key, upcall_info);
315 	else
316 		err = queue_gso_packets(dp, skb, key, upcall_info);
317 	if (err)
318 		goto err;
319 
320 	return 0;
321 
322 err:
323 	stats = this_cpu_ptr(dp->stats_percpu);
324 
325 	u64_stats_update_begin(&stats->syncp);
326 	stats->n_lost++;
327 	u64_stats_update_end(&stats->syncp);
328 
329 	return err;
330 }
331 
332 static int queue_gso_packets(struct datapath *dp, struct sk_buff *skb,
333 			     const struct sw_flow_key *key,
334 			     const struct dp_upcall_info *upcall_info)
335 {
336 	unsigned short gso_type = skb_shinfo(skb)->gso_type;
337 	struct sw_flow_key later_key;
338 	struct sk_buff *segs, *nskb;
339 	struct ovs_skb_cb ovs_cb;
340 	int err;
341 
342 	ovs_cb = *OVS_CB(skb);
343 	segs = __skb_gso_segment(skb, NETIF_F_SG, false);
344 	*OVS_CB(skb) = ovs_cb;
345 	if (IS_ERR(segs))
346 		return PTR_ERR(segs);
347 	if (segs == NULL)
348 		return -EINVAL;
349 
350 	if (gso_type & SKB_GSO_UDP) {
351 		/* The initial flow key extracted by ovs_flow_key_extract()
352 		 * in this case is for a first fragment, so we need to
353 		 * properly mark later fragments.
354 		 */
355 		later_key = *key;
356 		later_key.ip.frag = OVS_FRAG_TYPE_LATER;
357 	}
358 
359 	/* Queue all of the segments. */
360 	skb = segs;
361 	do {
362 		*OVS_CB(skb) = ovs_cb;
363 		if (gso_type & SKB_GSO_UDP && skb != segs)
364 			key = &later_key;
365 
366 		err = queue_userspace_packet(dp, skb, key, upcall_info);
367 		if (err)
368 			break;
369 
370 	} while ((skb = skb->next));
371 
372 	/* Free all of the segments. */
373 	skb = segs;
374 	do {
375 		nskb = skb->next;
376 		if (err)
377 			kfree_skb(skb);
378 		else
379 			consume_skb(skb);
380 	} while ((skb = nskb));
381 	return err;
382 }
383 
384 static size_t upcall_msg_size(const struct dp_upcall_info *upcall_info,
385 			      unsigned int hdrlen)
386 {
387 	size_t size = NLMSG_ALIGN(sizeof(struct ovs_header))
388 		+ nla_total_size(hdrlen) /* OVS_PACKET_ATTR_PACKET */
389 		+ nla_total_size(ovs_key_attr_size()); /* OVS_PACKET_ATTR_KEY */
390 
391 	/* OVS_PACKET_ATTR_USERDATA */
392 	if (upcall_info->userdata)
393 		size += NLA_ALIGN(upcall_info->userdata->nla_len);
394 
395 	/* OVS_PACKET_ATTR_EGRESS_TUN_KEY */
396 	if (upcall_info->egress_tun_info)
397 		size += nla_total_size(ovs_tun_key_attr_size());
398 
399 	/* OVS_PACKET_ATTR_ACTIONS */
400 	if (upcall_info->actions_len)
401 		size += nla_total_size(upcall_info->actions_len);
402 
403 	return size;
404 }
405 
406 static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
407 				  const struct sw_flow_key *key,
408 				  const struct dp_upcall_info *upcall_info)
409 {
410 	struct ovs_header *upcall;
411 	struct sk_buff *nskb = NULL;
412 	struct sk_buff *user_skb = NULL; /* to be queued to userspace */
413 	struct nlattr *nla;
414 	struct genl_info info = {
415 		.dst_sk = ovs_dp_get_net(dp)->genl_sock,
416 		.snd_portid = upcall_info->portid,
417 	};
418 	size_t len;
419 	unsigned int hlen;
420 	int err, dp_ifindex;
421 
422 	dp_ifindex = get_dpifindex(dp);
423 	if (!dp_ifindex)
424 		return -ENODEV;
425 
426 	if (skb_vlan_tag_present(skb)) {
427 		nskb = skb_clone(skb, GFP_ATOMIC);
428 		if (!nskb)
429 			return -ENOMEM;
430 
431 		nskb = __vlan_hwaccel_push_inside(nskb);
432 		if (!nskb)
433 			return -ENOMEM;
434 
435 		skb = nskb;
436 	}
437 
438 	if (nla_attr_size(skb->len) > USHRT_MAX) {
439 		err = -EFBIG;
440 		goto out;
441 	}
442 
443 	/* Complete checksum if needed */
444 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
445 	    (err = skb_checksum_help(skb)))
446 		goto out;
447 
448 	/* Older versions of OVS user space enforce alignment of the last
449 	 * Netlink attribute to NLA_ALIGNTO which would require extensive
450 	 * padding logic. Only perform zerocopy if padding is not required.
451 	 */
452 	if (dp->user_features & OVS_DP_F_UNALIGNED)
453 		hlen = skb_zerocopy_headlen(skb);
454 	else
455 		hlen = skb->len;
456 
457 	len = upcall_msg_size(upcall_info, hlen);
458 	user_skb = genlmsg_new_unicast(len, &info, GFP_ATOMIC);
459 	if (!user_skb) {
460 		err = -ENOMEM;
461 		goto out;
462 	}
463 
464 	upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
465 			     0, upcall_info->cmd);
466 	upcall->dp_ifindex = dp_ifindex;
467 
468 	err = ovs_nla_put_key(key, key, OVS_PACKET_ATTR_KEY, false, user_skb);
469 	BUG_ON(err);
470 
471 	if (upcall_info->userdata)
472 		__nla_put(user_skb, OVS_PACKET_ATTR_USERDATA,
473 			  nla_len(upcall_info->userdata),
474 			  nla_data(upcall_info->userdata));
475 
476 	if (upcall_info->egress_tun_info) {
477 		nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_EGRESS_TUN_KEY);
478 		err = ovs_nla_put_egress_tunnel_key(user_skb,
479 						    upcall_info->egress_tun_info);
480 		BUG_ON(err);
481 		nla_nest_end(user_skb, nla);
482 	}
483 
484 	if (upcall_info->actions_len) {
485 		nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_ACTIONS);
486 		err = ovs_nla_put_actions(upcall_info->actions,
487 					  upcall_info->actions_len,
488 					  user_skb);
489 		if (!err)
490 			nla_nest_end(user_skb, nla);
491 		else
492 			nla_nest_cancel(user_skb, nla);
493 	}
494 
495 	/* Only reserve room for attribute header, packet data is added
496 	 * in skb_zerocopy() */
497 	if (!(nla = nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, 0))) {
498 		err = -ENOBUFS;
499 		goto out;
500 	}
501 	nla->nla_len = nla_attr_size(skb->len);
502 
503 	err = skb_zerocopy(user_skb, skb, skb->len, hlen);
504 	if (err)
505 		goto out;
506 
507 	/* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */
508 	if (!(dp->user_features & OVS_DP_F_UNALIGNED)) {
509 		size_t plen = NLA_ALIGN(user_skb->len) - user_skb->len;
510 
511 		if (plen > 0)
512 			memset(skb_put(user_skb, plen), 0, plen);
513 	}
514 
515 	((struct nlmsghdr *) user_skb->data)->nlmsg_len = user_skb->len;
516 
517 	err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
518 	user_skb = NULL;
519 out:
520 	if (err)
521 		skb_tx_error(skb);
522 	kfree_skb(user_skb);
523 	kfree_skb(nskb);
524 	return err;
525 }
526 
527 static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
528 {
529 	struct ovs_header *ovs_header = info->userhdr;
530 	struct nlattr **a = info->attrs;
531 	struct sw_flow_actions *acts;
532 	struct sk_buff *packet;
533 	struct sw_flow *flow;
534 	struct sw_flow_actions *sf_acts;
535 	struct datapath *dp;
536 	struct ethhdr *eth;
537 	struct vport *input_vport;
538 	int len;
539 	int err;
540 	bool log = !a[OVS_PACKET_ATTR_PROBE];
541 
542 	err = -EINVAL;
543 	if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] ||
544 	    !a[OVS_PACKET_ATTR_ACTIONS])
545 		goto err;
546 
547 	len = nla_len(a[OVS_PACKET_ATTR_PACKET]);
548 	packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL);
549 	err = -ENOMEM;
550 	if (!packet)
551 		goto err;
552 	skb_reserve(packet, NET_IP_ALIGN);
553 
554 	nla_memcpy(__skb_put(packet, len), a[OVS_PACKET_ATTR_PACKET], len);
555 
556 	skb_reset_mac_header(packet);
557 	eth = eth_hdr(packet);
558 
559 	/* Normally, setting the skb 'protocol' field would be handled by a
560 	 * call to eth_type_trans(), but it assumes there's a sending
561 	 * device, which we may not have. */
562 	if (eth_proto_is_802_3(eth->h_proto))
563 		packet->protocol = eth->h_proto;
564 	else
565 		packet->protocol = htons(ETH_P_802_2);
566 
567 	/* Build an sw_flow for sending this packet. */
568 	flow = ovs_flow_alloc();
569 	err = PTR_ERR(flow);
570 	if (IS_ERR(flow))
571 		goto err_kfree_skb;
572 
573 	err = ovs_flow_key_extract_userspace(a[OVS_PACKET_ATTR_KEY], packet,
574 					     &flow->key, log);
575 	if (err)
576 		goto err_flow_free;
577 
578 	err = ovs_nla_copy_actions(a[OVS_PACKET_ATTR_ACTIONS],
579 				   &flow->key, &acts, log);
580 	if (err)
581 		goto err_flow_free;
582 
583 	rcu_assign_pointer(flow->sf_acts, acts);
584 	OVS_CB(packet)->egress_tun_info = NULL;
585 	packet->priority = flow->key.phy.priority;
586 	packet->mark = flow->key.phy.skb_mark;
587 
588 	rcu_read_lock();
589 	dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex);
590 	err = -ENODEV;
591 	if (!dp)
592 		goto err_unlock;
593 
594 	input_vport = ovs_vport_rcu(dp, flow->key.phy.in_port);
595 	if (!input_vport)
596 		input_vport = ovs_vport_rcu(dp, OVSP_LOCAL);
597 
598 	if (!input_vport)
599 		goto err_unlock;
600 
601 	OVS_CB(packet)->input_vport = input_vport;
602 	sf_acts = rcu_dereference(flow->sf_acts);
603 
604 	local_bh_disable();
605 	err = ovs_execute_actions(dp, packet, sf_acts, &flow->key);
606 	local_bh_enable();
607 	rcu_read_unlock();
608 
609 	ovs_flow_free(flow, false);
610 	return err;
611 
612 err_unlock:
613 	rcu_read_unlock();
614 err_flow_free:
615 	ovs_flow_free(flow, false);
616 err_kfree_skb:
617 	kfree_skb(packet);
618 err:
619 	return err;
620 }
621 
622 static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = {
623 	[OVS_PACKET_ATTR_PACKET] = { .len = ETH_HLEN },
624 	[OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED },
625 	[OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED },
626 	[OVS_PACKET_ATTR_PROBE] = { .type = NLA_FLAG },
627 };
628 
629 static const struct genl_ops dp_packet_genl_ops[] = {
630 	{ .cmd = OVS_PACKET_CMD_EXECUTE,
631 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
632 	  .policy = packet_policy,
633 	  .doit = ovs_packet_cmd_execute
634 	}
635 };
636 
637 static struct genl_family dp_packet_genl_family = {
638 	.id = GENL_ID_GENERATE,
639 	.hdrsize = sizeof(struct ovs_header),
640 	.name = OVS_PACKET_FAMILY,
641 	.version = OVS_PACKET_VERSION,
642 	.maxattr = OVS_PACKET_ATTR_MAX,
643 	.netnsok = true,
644 	.parallel_ops = true,
645 	.ops = dp_packet_genl_ops,
646 	.n_ops = ARRAY_SIZE(dp_packet_genl_ops),
647 };
648 
649 static void get_dp_stats(const struct datapath *dp, struct ovs_dp_stats *stats,
650 			 struct ovs_dp_megaflow_stats *mega_stats)
651 {
652 	int i;
653 
654 	memset(mega_stats, 0, sizeof(*mega_stats));
655 
656 	stats->n_flows = ovs_flow_tbl_count(&dp->table);
657 	mega_stats->n_masks = ovs_flow_tbl_num_masks(&dp->table);
658 
659 	stats->n_hit = stats->n_missed = stats->n_lost = 0;
660 
661 	for_each_possible_cpu(i) {
662 		const struct dp_stats_percpu *percpu_stats;
663 		struct dp_stats_percpu local_stats;
664 		unsigned int start;
665 
666 		percpu_stats = per_cpu_ptr(dp->stats_percpu, i);
667 
668 		do {
669 			start = u64_stats_fetch_begin_irq(&percpu_stats->syncp);
670 			local_stats = *percpu_stats;
671 		} while (u64_stats_fetch_retry_irq(&percpu_stats->syncp, start));
672 
673 		stats->n_hit += local_stats.n_hit;
674 		stats->n_missed += local_stats.n_missed;
675 		stats->n_lost += local_stats.n_lost;
676 		mega_stats->n_mask_hit += local_stats.n_mask_hit;
677 	}
678 }
679 
680 static bool should_fill_key(const struct sw_flow_id *sfid, uint32_t ufid_flags)
681 {
682 	return ovs_identifier_is_ufid(sfid) &&
683 	       !(ufid_flags & OVS_UFID_F_OMIT_KEY);
684 }
685 
686 static bool should_fill_mask(uint32_t ufid_flags)
687 {
688 	return !(ufid_flags & OVS_UFID_F_OMIT_MASK);
689 }
690 
691 static bool should_fill_actions(uint32_t ufid_flags)
692 {
693 	return !(ufid_flags & OVS_UFID_F_OMIT_ACTIONS);
694 }
695 
696 static size_t ovs_flow_cmd_msg_size(const struct sw_flow_actions *acts,
697 				    const struct sw_flow_id *sfid,
698 				    uint32_t ufid_flags)
699 {
700 	size_t len = NLMSG_ALIGN(sizeof(struct ovs_header));
701 
702 	/* OVS_FLOW_ATTR_UFID */
703 	if (sfid && ovs_identifier_is_ufid(sfid))
704 		len += nla_total_size(sfid->ufid_len);
705 
706 	/* OVS_FLOW_ATTR_KEY */
707 	if (!sfid || should_fill_key(sfid, ufid_flags))
708 		len += nla_total_size(ovs_key_attr_size());
709 
710 	/* OVS_FLOW_ATTR_MASK */
711 	if (should_fill_mask(ufid_flags))
712 		len += nla_total_size(ovs_key_attr_size());
713 
714 	/* OVS_FLOW_ATTR_ACTIONS */
715 	if (should_fill_actions(ufid_flags))
716 		len += nla_total_size(acts->actions_len);
717 
718 	return len
719 		+ nla_total_size(sizeof(struct ovs_flow_stats)) /* OVS_FLOW_ATTR_STATS */
720 		+ nla_total_size(1) /* OVS_FLOW_ATTR_TCP_FLAGS */
721 		+ nla_total_size(8); /* OVS_FLOW_ATTR_USED */
722 }
723 
724 /* Called with ovs_mutex or RCU read lock. */
725 static int ovs_flow_cmd_fill_stats(const struct sw_flow *flow,
726 				   struct sk_buff *skb)
727 {
728 	struct ovs_flow_stats stats;
729 	__be16 tcp_flags;
730 	unsigned long used;
731 
732 	ovs_flow_stats_get(flow, &stats, &used, &tcp_flags);
733 
734 	if (used &&
735 	    nla_put_u64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used)))
736 		return -EMSGSIZE;
737 
738 	if (stats.n_packets &&
739 	    nla_put(skb, OVS_FLOW_ATTR_STATS, sizeof(struct ovs_flow_stats), &stats))
740 		return -EMSGSIZE;
741 
742 	if ((u8)ntohs(tcp_flags) &&
743 	     nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags)))
744 		return -EMSGSIZE;
745 
746 	return 0;
747 }
748 
749 /* Called with ovs_mutex or RCU read lock. */
750 static int ovs_flow_cmd_fill_actions(const struct sw_flow *flow,
751 				     struct sk_buff *skb, int skb_orig_len)
752 {
753 	struct nlattr *start;
754 	int err;
755 
756 	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
757 	 * this is the first flow to be dumped into 'skb'.  This is unusual for
758 	 * Netlink but individual action lists can be longer than
759 	 * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this.
760 	 * The userspace caller can always fetch the actions separately if it
761 	 * really wants them.  (Most userspace callers in fact don't care.)
762 	 *
763 	 * This can only fail for dump operations because the skb is always
764 	 * properly sized for single flows.
765 	 */
766 	start = nla_nest_start(skb, OVS_FLOW_ATTR_ACTIONS);
767 	if (start) {
768 		const struct sw_flow_actions *sf_acts;
769 
770 		sf_acts = rcu_dereference_ovsl(flow->sf_acts);
771 		err = ovs_nla_put_actions(sf_acts->actions,
772 					  sf_acts->actions_len, skb);
773 
774 		if (!err)
775 			nla_nest_end(skb, start);
776 		else {
777 			if (skb_orig_len)
778 				return err;
779 
780 			nla_nest_cancel(skb, start);
781 		}
782 	} else if (skb_orig_len) {
783 		return -EMSGSIZE;
784 	}
785 
786 	return 0;
787 }
788 
789 /* Called with ovs_mutex or RCU read lock. */
790 static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
791 				  struct sk_buff *skb, u32 portid,
792 				  u32 seq, u32 flags, u8 cmd, u32 ufid_flags)
793 {
794 	const int skb_orig_len = skb->len;
795 	struct ovs_header *ovs_header;
796 	int err;
797 
798 	ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family,
799 				 flags, cmd);
800 	if (!ovs_header)
801 		return -EMSGSIZE;
802 
803 	ovs_header->dp_ifindex = dp_ifindex;
804 
805 	err = ovs_nla_put_identifier(flow, skb);
806 	if (err)
807 		goto error;
808 
809 	if (should_fill_key(&flow->id, ufid_flags)) {
810 		err = ovs_nla_put_masked_key(flow, skb);
811 		if (err)
812 			goto error;
813 	}
814 
815 	if (should_fill_mask(ufid_flags)) {
816 		err = ovs_nla_put_mask(flow, skb);
817 		if (err)
818 			goto error;
819 	}
820 
821 	err = ovs_flow_cmd_fill_stats(flow, skb);
822 	if (err)
823 		goto error;
824 
825 	if (should_fill_actions(ufid_flags)) {
826 		err = ovs_flow_cmd_fill_actions(flow, skb, skb_orig_len);
827 		if (err)
828 			goto error;
829 	}
830 
831 	genlmsg_end(skb, ovs_header);
832 	return 0;
833 
834 error:
835 	genlmsg_cancel(skb, ovs_header);
836 	return err;
837 }
838 
839 /* May not be called with RCU read lock. */
840 static struct sk_buff *ovs_flow_cmd_alloc_info(const struct sw_flow_actions *acts,
841 					       const struct sw_flow_id *sfid,
842 					       struct genl_info *info,
843 					       bool always,
844 					       uint32_t ufid_flags)
845 {
846 	struct sk_buff *skb;
847 	size_t len;
848 
849 	if (!always && !ovs_must_notify(&dp_flow_genl_family, info, 0))
850 		return NULL;
851 
852 	len = ovs_flow_cmd_msg_size(acts, sfid, ufid_flags);
853 	skb = genlmsg_new_unicast(len, info, GFP_KERNEL);
854 	if (!skb)
855 		return ERR_PTR(-ENOMEM);
856 
857 	return skb;
858 }
859 
860 /* Called with ovs_mutex. */
861 static struct sk_buff *ovs_flow_cmd_build_info(const struct sw_flow *flow,
862 					       int dp_ifindex,
863 					       struct genl_info *info, u8 cmd,
864 					       bool always, u32 ufid_flags)
865 {
866 	struct sk_buff *skb;
867 	int retval;
868 
869 	skb = ovs_flow_cmd_alloc_info(ovsl_dereference(flow->sf_acts),
870 				      &flow->id, info, always, ufid_flags);
871 	if (IS_ERR_OR_NULL(skb))
872 		return skb;
873 
874 	retval = ovs_flow_cmd_fill_info(flow, dp_ifindex, skb,
875 					info->snd_portid, info->snd_seq, 0,
876 					cmd, ufid_flags);
877 	BUG_ON(retval < 0);
878 	return skb;
879 }
880 
881 static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
882 {
883 	struct nlattr **a = info->attrs;
884 	struct ovs_header *ovs_header = info->userhdr;
885 	struct sw_flow *flow = NULL, *new_flow;
886 	struct sw_flow_mask mask;
887 	struct sk_buff *reply;
888 	struct datapath *dp;
889 	struct sw_flow_key key;
890 	struct sw_flow_actions *acts;
891 	struct sw_flow_match match;
892 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
893 	int error;
894 	bool log = !a[OVS_FLOW_ATTR_PROBE];
895 
896 	/* Must have key and actions. */
897 	error = -EINVAL;
898 	if (!a[OVS_FLOW_ATTR_KEY]) {
899 		OVS_NLERR(log, "Flow key attr not present in new flow.");
900 		goto error;
901 	}
902 	if (!a[OVS_FLOW_ATTR_ACTIONS]) {
903 		OVS_NLERR(log, "Flow actions attr not present in new flow.");
904 		goto error;
905 	}
906 
907 	/* Most of the time we need to allocate a new flow, do it before
908 	 * locking.
909 	 */
910 	new_flow = ovs_flow_alloc();
911 	if (IS_ERR(new_flow)) {
912 		error = PTR_ERR(new_flow);
913 		goto error;
914 	}
915 
916 	/* Extract key. */
917 	ovs_match_init(&match, &key, &mask);
918 	error = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY],
919 				  a[OVS_FLOW_ATTR_MASK], log);
920 	if (error)
921 		goto err_kfree_flow;
922 
923 	ovs_flow_mask_key(&new_flow->key, &key, &mask);
924 
925 	/* Extract flow identifier. */
926 	error = ovs_nla_get_identifier(&new_flow->id, a[OVS_FLOW_ATTR_UFID],
927 				       &key, log);
928 	if (error)
929 		goto err_kfree_flow;
930 
931 	/* Validate actions. */
932 	error = ovs_nla_copy_actions(a[OVS_FLOW_ATTR_ACTIONS], &new_flow->key,
933 				     &acts, log);
934 	if (error) {
935 		OVS_NLERR(log, "Flow actions may not be safe on all matching packets.");
936 		goto err_kfree_flow;
937 	}
938 
939 	reply = ovs_flow_cmd_alloc_info(acts, &new_flow->id, info, false,
940 					ufid_flags);
941 	if (IS_ERR(reply)) {
942 		error = PTR_ERR(reply);
943 		goto err_kfree_acts;
944 	}
945 
946 	ovs_lock();
947 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
948 	if (unlikely(!dp)) {
949 		error = -ENODEV;
950 		goto err_unlock_ovs;
951 	}
952 
953 	/* Check if this is a duplicate flow */
954 	if (ovs_identifier_is_ufid(&new_flow->id))
955 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &new_flow->id);
956 	if (!flow)
957 		flow = ovs_flow_tbl_lookup(&dp->table, &key);
958 	if (likely(!flow)) {
959 		rcu_assign_pointer(new_flow->sf_acts, acts);
960 
961 		/* Put flow in bucket. */
962 		error = ovs_flow_tbl_insert(&dp->table, new_flow, &mask);
963 		if (unlikely(error)) {
964 			acts = NULL;
965 			goto err_unlock_ovs;
966 		}
967 
968 		if (unlikely(reply)) {
969 			error = ovs_flow_cmd_fill_info(new_flow,
970 						       ovs_header->dp_ifindex,
971 						       reply, info->snd_portid,
972 						       info->snd_seq, 0,
973 						       OVS_FLOW_CMD_NEW,
974 						       ufid_flags);
975 			BUG_ON(error < 0);
976 		}
977 		ovs_unlock();
978 	} else {
979 		struct sw_flow_actions *old_acts;
980 
981 		/* Bail out if we're not allowed to modify an existing flow.
982 		 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
983 		 * because Generic Netlink treats the latter as a dump
984 		 * request.  We also accept NLM_F_EXCL in case that bug ever
985 		 * gets fixed.
986 		 */
987 		if (unlikely(info->nlhdr->nlmsg_flags & (NLM_F_CREATE
988 							 | NLM_F_EXCL))) {
989 			error = -EEXIST;
990 			goto err_unlock_ovs;
991 		}
992 		/* The flow identifier has to be the same for flow updates.
993 		 * Look for any overlapping flow.
994 		 */
995 		if (unlikely(!ovs_flow_cmp(flow, &match))) {
996 			if (ovs_identifier_is_key(&flow->id))
997 				flow = ovs_flow_tbl_lookup_exact(&dp->table,
998 								 &match);
999 			else /* UFID matches but key is different */
1000 				flow = NULL;
1001 			if (!flow) {
1002 				error = -ENOENT;
1003 				goto err_unlock_ovs;
1004 			}
1005 		}
1006 		/* Update actions. */
1007 		old_acts = ovsl_dereference(flow->sf_acts);
1008 		rcu_assign_pointer(flow->sf_acts, acts);
1009 
1010 		if (unlikely(reply)) {
1011 			error = ovs_flow_cmd_fill_info(flow,
1012 						       ovs_header->dp_ifindex,
1013 						       reply, info->snd_portid,
1014 						       info->snd_seq, 0,
1015 						       OVS_FLOW_CMD_NEW,
1016 						       ufid_flags);
1017 			BUG_ON(error < 0);
1018 		}
1019 		ovs_unlock();
1020 
1021 		ovs_nla_free_flow_actions(old_acts);
1022 		ovs_flow_free(new_flow, false);
1023 	}
1024 
1025 	if (reply)
1026 		ovs_notify(&dp_flow_genl_family, reply, info);
1027 	return 0;
1028 
1029 err_unlock_ovs:
1030 	ovs_unlock();
1031 	kfree_skb(reply);
1032 err_kfree_acts:
1033 	kfree(acts);
1034 err_kfree_flow:
1035 	ovs_flow_free(new_flow, false);
1036 error:
1037 	return error;
1038 }
1039 
1040 /* Factor out action copy to avoid "Wframe-larger-than=1024" warning. */
1041 static struct sw_flow_actions *get_flow_actions(const struct nlattr *a,
1042 						const struct sw_flow_key *key,
1043 						const struct sw_flow_mask *mask,
1044 						bool log)
1045 {
1046 	struct sw_flow_actions *acts;
1047 	struct sw_flow_key masked_key;
1048 	int error;
1049 
1050 	ovs_flow_mask_key(&masked_key, key, mask);
1051 	error = ovs_nla_copy_actions(a, &masked_key, &acts, log);
1052 	if (error) {
1053 		OVS_NLERR(log,
1054 			  "Actions may not be safe on all matching packets");
1055 		return ERR_PTR(error);
1056 	}
1057 
1058 	return acts;
1059 }
1060 
1061 static int ovs_flow_cmd_set(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 sw_flow *flow;
1067 	struct sw_flow_mask mask;
1068 	struct sk_buff *reply = NULL;
1069 	struct datapath *dp;
1070 	struct sw_flow_actions *old_acts = NULL, *acts = NULL;
1071 	struct sw_flow_match match;
1072 	struct sw_flow_id sfid;
1073 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1074 	int error;
1075 	bool log = !a[OVS_FLOW_ATTR_PROBE];
1076 	bool ufid_present;
1077 
1078 	/* Extract key. */
1079 	error = -EINVAL;
1080 	if (!a[OVS_FLOW_ATTR_KEY]) {
1081 		OVS_NLERR(log, "Flow key attribute not present in set flow.");
1082 		goto error;
1083 	}
1084 
1085 	ufid_present = ovs_nla_get_ufid(&sfid, a[OVS_FLOW_ATTR_UFID], log);
1086 	ovs_match_init(&match, &key, &mask);
1087 	error = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY],
1088 				  a[OVS_FLOW_ATTR_MASK], log);
1089 	if (error)
1090 		goto error;
1091 
1092 	/* Validate actions. */
1093 	if (a[OVS_FLOW_ATTR_ACTIONS]) {
1094 		acts = get_flow_actions(a[OVS_FLOW_ATTR_ACTIONS], &key, &mask,
1095 					log);
1096 		if (IS_ERR(acts)) {
1097 			error = PTR_ERR(acts);
1098 			goto error;
1099 		}
1100 
1101 		/* Can allocate before locking if have acts. */
1102 		reply = ovs_flow_cmd_alloc_info(acts, &sfid, info, false,
1103 						ufid_flags);
1104 		if (IS_ERR(reply)) {
1105 			error = PTR_ERR(reply);
1106 			goto err_kfree_acts;
1107 		}
1108 	}
1109 
1110 	ovs_lock();
1111 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1112 	if (unlikely(!dp)) {
1113 		error = -ENODEV;
1114 		goto err_unlock_ovs;
1115 	}
1116 	/* Check that the flow exists. */
1117 	if (ufid_present)
1118 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &sfid);
1119 	else
1120 		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1121 	if (unlikely(!flow)) {
1122 		error = -ENOENT;
1123 		goto err_unlock_ovs;
1124 	}
1125 
1126 	/* Update actions, if present. */
1127 	if (likely(acts)) {
1128 		old_acts = ovsl_dereference(flow->sf_acts);
1129 		rcu_assign_pointer(flow->sf_acts, acts);
1130 
1131 		if (unlikely(reply)) {
1132 			error = ovs_flow_cmd_fill_info(flow,
1133 						       ovs_header->dp_ifindex,
1134 						       reply, info->snd_portid,
1135 						       info->snd_seq, 0,
1136 						       OVS_FLOW_CMD_NEW,
1137 						       ufid_flags);
1138 			BUG_ON(error < 0);
1139 		}
1140 	} else {
1141 		/* Could not alloc without acts before locking. */
1142 		reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex,
1143 						info, OVS_FLOW_CMD_NEW, false,
1144 						ufid_flags);
1145 
1146 		if (unlikely(IS_ERR(reply))) {
1147 			error = PTR_ERR(reply);
1148 			goto err_unlock_ovs;
1149 		}
1150 	}
1151 
1152 	/* Clear stats. */
1153 	if (a[OVS_FLOW_ATTR_CLEAR])
1154 		ovs_flow_stats_clear(flow);
1155 	ovs_unlock();
1156 
1157 	if (reply)
1158 		ovs_notify(&dp_flow_genl_family, reply, info);
1159 	if (old_acts)
1160 		ovs_nla_free_flow_actions(old_acts);
1161 
1162 	return 0;
1163 
1164 err_unlock_ovs:
1165 	ovs_unlock();
1166 	kfree_skb(reply);
1167 err_kfree_acts:
1168 	kfree(acts);
1169 error:
1170 	return error;
1171 }
1172 
1173 static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
1174 {
1175 	struct nlattr **a = info->attrs;
1176 	struct ovs_header *ovs_header = info->userhdr;
1177 	struct sw_flow_key key;
1178 	struct sk_buff *reply;
1179 	struct sw_flow *flow;
1180 	struct datapath *dp;
1181 	struct sw_flow_match match;
1182 	struct sw_flow_id ufid;
1183 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1184 	int err = 0;
1185 	bool log = !a[OVS_FLOW_ATTR_PROBE];
1186 	bool ufid_present;
1187 
1188 	ufid_present = ovs_nla_get_ufid(&ufid, a[OVS_FLOW_ATTR_UFID], log);
1189 	if (a[OVS_FLOW_ATTR_KEY]) {
1190 		ovs_match_init(&match, &key, NULL);
1191 		err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL,
1192 					log);
1193 	} else if (!ufid_present) {
1194 		OVS_NLERR(log,
1195 			  "Flow get message rejected, Key attribute missing.");
1196 		err = -EINVAL;
1197 	}
1198 	if (err)
1199 		return err;
1200 
1201 	ovs_lock();
1202 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1203 	if (!dp) {
1204 		err = -ENODEV;
1205 		goto unlock;
1206 	}
1207 
1208 	if (ufid_present)
1209 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &ufid);
1210 	else
1211 		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1212 	if (!flow) {
1213 		err = -ENOENT;
1214 		goto unlock;
1215 	}
1216 
1217 	reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex, info,
1218 					OVS_FLOW_CMD_NEW, true, ufid_flags);
1219 	if (IS_ERR(reply)) {
1220 		err = PTR_ERR(reply);
1221 		goto unlock;
1222 	}
1223 
1224 	ovs_unlock();
1225 	return genlmsg_reply(reply, info);
1226 unlock:
1227 	ovs_unlock();
1228 	return err;
1229 }
1230 
1231 static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
1232 {
1233 	struct nlattr **a = info->attrs;
1234 	struct ovs_header *ovs_header = info->userhdr;
1235 	struct sw_flow_key key;
1236 	struct sk_buff *reply;
1237 	struct sw_flow *flow = NULL;
1238 	struct datapath *dp;
1239 	struct sw_flow_match match;
1240 	struct sw_flow_id ufid;
1241 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1242 	int err;
1243 	bool log = !a[OVS_FLOW_ATTR_PROBE];
1244 	bool ufid_present;
1245 
1246 	ufid_present = ovs_nla_get_ufid(&ufid, a[OVS_FLOW_ATTR_UFID], log);
1247 	if (a[OVS_FLOW_ATTR_KEY]) {
1248 		ovs_match_init(&match, &key, NULL);
1249 		err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL,
1250 					log);
1251 		if (unlikely(err))
1252 			return err;
1253 	}
1254 
1255 	ovs_lock();
1256 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1257 	if (unlikely(!dp)) {
1258 		err = -ENODEV;
1259 		goto unlock;
1260 	}
1261 
1262 	if (unlikely(!a[OVS_FLOW_ATTR_KEY] && !ufid_present)) {
1263 		err = ovs_flow_tbl_flush(&dp->table);
1264 		goto unlock;
1265 	}
1266 
1267 	if (ufid_present)
1268 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &ufid);
1269 	else
1270 		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1271 	if (unlikely(!flow)) {
1272 		err = -ENOENT;
1273 		goto unlock;
1274 	}
1275 
1276 	ovs_flow_tbl_remove(&dp->table, flow);
1277 	ovs_unlock();
1278 
1279 	reply = ovs_flow_cmd_alloc_info((const struct sw_flow_actions __force *) flow->sf_acts,
1280 					&flow->id, info, false, ufid_flags);
1281 	if (likely(reply)) {
1282 		if (likely(!IS_ERR(reply))) {
1283 			rcu_read_lock();	/*To keep RCU checker happy. */
1284 			err = ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex,
1285 						     reply, info->snd_portid,
1286 						     info->snd_seq, 0,
1287 						     OVS_FLOW_CMD_DEL,
1288 						     ufid_flags);
1289 			rcu_read_unlock();
1290 			BUG_ON(err < 0);
1291 
1292 			ovs_notify(&dp_flow_genl_family, reply, info);
1293 		} else {
1294 			netlink_set_err(sock_net(skb->sk)->genl_sock, 0, 0, PTR_ERR(reply));
1295 		}
1296 	}
1297 
1298 	ovs_flow_free(flow, true);
1299 	return 0;
1300 unlock:
1301 	ovs_unlock();
1302 	return err;
1303 }
1304 
1305 static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1306 {
1307 	struct nlattr *a[__OVS_FLOW_ATTR_MAX];
1308 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1309 	struct table_instance *ti;
1310 	struct datapath *dp;
1311 	u32 ufid_flags;
1312 	int err;
1313 
1314 	err = genlmsg_parse(cb->nlh, &dp_flow_genl_family, a,
1315 			    OVS_FLOW_ATTR_MAX, flow_policy);
1316 	if (err)
1317 		return err;
1318 	ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1319 
1320 	rcu_read_lock();
1321 	dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex);
1322 	if (!dp) {
1323 		rcu_read_unlock();
1324 		return -ENODEV;
1325 	}
1326 
1327 	ti = rcu_dereference(dp->table.ti);
1328 	for (;;) {
1329 		struct sw_flow *flow;
1330 		u32 bucket, obj;
1331 
1332 		bucket = cb->args[0];
1333 		obj = cb->args[1];
1334 		flow = ovs_flow_tbl_dump_next(ti, &bucket, &obj);
1335 		if (!flow)
1336 			break;
1337 
1338 		if (ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex, skb,
1339 					   NETLINK_CB(cb->skb).portid,
1340 					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
1341 					   OVS_FLOW_CMD_NEW, ufid_flags) < 0)
1342 			break;
1343 
1344 		cb->args[0] = bucket;
1345 		cb->args[1] = obj;
1346 	}
1347 	rcu_read_unlock();
1348 	return skb->len;
1349 }
1350 
1351 static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = {
1352 	[OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED },
1353 	[OVS_FLOW_ATTR_MASK] = { .type = NLA_NESTED },
1354 	[OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED },
1355 	[OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG },
1356 	[OVS_FLOW_ATTR_PROBE] = { .type = NLA_FLAG },
1357 	[OVS_FLOW_ATTR_UFID] = { .type = NLA_UNSPEC, .len = 1 },
1358 	[OVS_FLOW_ATTR_UFID_FLAGS] = { .type = NLA_U32 },
1359 };
1360 
1361 static const struct genl_ops dp_flow_genl_ops[] = {
1362 	{ .cmd = OVS_FLOW_CMD_NEW,
1363 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1364 	  .policy = flow_policy,
1365 	  .doit = ovs_flow_cmd_new
1366 	},
1367 	{ .cmd = OVS_FLOW_CMD_DEL,
1368 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1369 	  .policy = flow_policy,
1370 	  .doit = ovs_flow_cmd_del
1371 	},
1372 	{ .cmd = OVS_FLOW_CMD_GET,
1373 	  .flags = 0,		    /* OK for unprivileged users. */
1374 	  .policy = flow_policy,
1375 	  .doit = ovs_flow_cmd_get,
1376 	  .dumpit = ovs_flow_cmd_dump
1377 	},
1378 	{ .cmd = OVS_FLOW_CMD_SET,
1379 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1380 	  .policy = flow_policy,
1381 	  .doit = ovs_flow_cmd_set,
1382 	},
1383 };
1384 
1385 static struct genl_family dp_flow_genl_family = {
1386 	.id = GENL_ID_GENERATE,
1387 	.hdrsize = sizeof(struct ovs_header),
1388 	.name = OVS_FLOW_FAMILY,
1389 	.version = OVS_FLOW_VERSION,
1390 	.maxattr = OVS_FLOW_ATTR_MAX,
1391 	.netnsok = true,
1392 	.parallel_ops = true,
1393 	.ops = dp_flow_genl_ops,
1394 	.n_ops = ARRAY_SIZE(dp_flow_genl_ops),
1395 	.mcgrps = &ovs_dp_flow_multicast_group,
1396 	.n_mcgrps = 1,
1397 };
1398 
1399 static size_t ovs_dp_cmd_msg_size(void)
1400 {
1401 	size_t msgsize = NLMSG_ALIGN(sizeof(struct ovs_header));
1402 
1403 	msgsize += nla_total_size(IFNAMSIZ);
1404 	msgsize += nla_total_size(sizeof(struct ovs_dp_stats));
1405 	msgsize += nla_total_size(sizeof(struct ovs_dp_megaflow_stats));
1406 	msgsize += nla_total_size(sizeof(u32)); /* OVS_DP_ATTR_USER_FEATURES */
1407 
1408 	return msgsize;
1409 }
1410 
1411 /* Called with ovs_mutex. */
1412 static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
1413 				u32 portid, u32 seq, u32 flags, u8 cmd)
1414 {
1415 	struct ovs_header *ovs_header;
1416 	struct ovs_dp_stats dp_stats;
1417 	struct ovs_dp_megaflow_stats dp_megaflow_stats;
1418 	int err;
1419 
1420 	ovs_header = genlmsg_put(skb, portid, seq, &dp_datapath_genl_family,
1421 				   flags, cmd);
1422 	if (!ovs_header)
1423 		goto error;
1424 
1425 	ovs_header->dp_ifindex = get_dpifindex(dp);
1426 
1427 	err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp));
1428 	if (err)
1429 		goto nla_put_failure;
1430 
1431 	get_dp_stats(dp, &dp_stats, &dp_megaflow_stats);
1432 	if (nla_put(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats),
1433 			&dp_stats))
1434 		goto nla_put_failure;
1435 
1436 	if (nla_put(skb, OVS_DP_ATTR_MEGAFLOW_STATS,
1437 			sizeof(struct ovs_dp_megaflow_stats),
1438 			&dp_megaflow_stats))
1439 		goto nla_put_failure;
1440 
1441 	if (nla_put_u32(skb, OVS_DP_ATTR_USER_FEATURES, dp->user_features))
1442 		goto nla_put_failure;
1443 
1444 	genlmsg_end(skb, ovs_header);
1445 	return 0;
1446 
1447 nla_put_failure:
1448 	genlmsg_cancel(skb, ovs_header);
1449 error:
1450 	return -EMSGSIZE;
1451 }
1452 
1453 static struct sk_buff *ovs_dp_cmd_alloc_info(struct genl_info *info)
1454 {
1455 	return genlmsg_new_unicast(ovs_dp_cmd_msg_size(), info, GFP_KERNEL);
1456 }
1457 
1458 /* Called with rcu_read_lock or ovs_mutex. */
1459 static struct datapath *lookup_datapath(struct net *net,
1460 					const struct ovs_header *ovs_header,
1461 					struct nlattr *a[OVS_DP_ATTR_MAX + 1])
1462 {
1463 	struct datapath *dp;
1464 
1465 	if (!a[OVS_DP_ATTR_NAME])
1466 		dp = get_dp(net, ovs_header->dp_ifindex);
1467 	else {
1468 		struct vport *vport;
1469 
1470 		vport = ovs_vport_locate(net, nla_data(a[OVS_DP_ATTR_NAME]));
1471 		dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL;
1472 	}
1473 	return dp ? dp : ERR_PTR(-ENODEV);
1474 }
1475 
1476 static void ovs_dp_reset_user_features(struct sk_buff *skb, struct genl_info *info)
1477 {
1478 	struct datapath *dp;
1479 
1480 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1481 	if (IS_ERR(dp))
1482 		return;
1483 
1484 	WARN(dp->user_features, "Dropping previously announced user features\n");
1485 	dp->user_features = 0;
1486 }
1487 
1488 static void ovs_dp_change(struct datapath *dp, struct nlattr *a[])
1489 {
1490 	if (a[OVS_DP_ATTR_USER_FEATURES])
1491 		dp->user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
1492 }
1493 
1494 static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
1495 {
1496 	struct nlattr **a = info->attrs;
1497 	struct vport_parms parms;
1498 	struct sk_buff *reply;
1499 	struct datapath *dp;
1500 	struct vport *vport;
1501 	struct ovs_net *ovs_net;
1502 	int err, i;
1503 
1504 	err = -EINVAL;
1505 	if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
1506 		goto err;
1507 
1508 	reply = ovs_dp_cmd_alloc_info(info);
1509 	if (!reply)
1510 		return -ENOMEM;
1511 
1512 	err = -ENOMEM;
1513 	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
1514 	if (dp == NULL)
1515 		goto err_free_reply;
1516 
1517 	ovs_dp_set_net(dp, sock_net(skb->sk));
1518 
1519 	/* Allocate table. */
1520 	err = ovs_flow_tbl_init(&dp->table);
1521 	if (err)
1522 		goto err_free_dp;
1523 
1524 	dp->stats_percpu = netdev_alloc_pcpu_stats(struct dp_stats_percpu);
1525 	if (!dp->stats_percpu) {
1526 		err = -ENOMEM;
1527 		goto err_destroy_table;
1528 	}
1529 
1530 	dp->ports = kmalloc(DP_VPORT_HASH_BUCKETS * sizeof(struct hlist_head),
1531 			    GFP_KERNEL);
1532 	if (!dp->ports) {
1533 		err = -ENOMEM;
1534 		goto err_destroy_percpu;
1535 	}
1536 
1537 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
1538 		INIT_HLIST_HEAD(&dp->ports[i]);
1539 
1540 	/* Set up our datapath device. */
1541 	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
1542 	parms.type = OVS_VPORT_TYPE_INTERNAL;
1543 	parms.options = NULL;
1544 	parms.dp = dp;
1545 	parms.port_no = OVSP_LOCAL;
1546 	parms.upcall_portids = a[OVS_DP_ATTR_UPCALL_PID];
1547 
1548 	ovs_dp_change(dp, a);
1549 
1550 	/* So far only local changes have been made, now need the lock. */
1551 	ovs_lock();
1552 
1553 	vport = new_vport(&parms);
1554 	if (IS_ERR(vport)) {
1555 		err = PTR_ERR(vport);
1556 		if (err == -EBUSY)
1557 			err = -EEXIST;
1558 
1559 		if (err == -EEXIST) {
1560 			/* An outdated user space instance that does not understand
1561 			 * the concept of user_features has attempted to create a new
1562 			 * datapath and is likely to reuse it. Drop all user features.
1563 			 */
1564 			if (info->genlhdr->version < OVS_DP_VER_FEATURES)
1565 				ovs_dp_reset_user_features(skb, info);
1566 		}
1567 
1568 		goto err_destroy_ports_array;
1569 	}
1570 
1571 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1572 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1573 	BUG_ON(err < 0);
1574 
1575 	ovs_net = net_generic(ovs_dp_get_net(dp), ovs_net_id);
1576 	list_add_tail_rcu(&dp->list_node, &ovs_net->dps);
1577 
1578 	ovs_unlock();
1579 
1580 	ovs_notify(&dp_datapath_genl_family, reply, info);
1581 	return 0;
1582 
1583 err_destroy_ports_array:
1584 	ovs_unlock();
1585 	kfree(dp->ports);
1586 err_destroy_percpu:
1587 	free_percpu(dp->stats_percpu);
1588 err_destroy_table:
1589 	ovs_flow_tbl_destroy(&dp->table);
1590 err_free_dp:
1591 	kfree(dp);
1592 err_free_reply:
1593 	kfree_skb(reply);
1594 err:
1595 	return err;
1596 }
1597 
1598 /* Called with ovs_mutex. */
1599 static void __dp_destroy(struct datapath *dp)
1600 {
1601 	int i;
1602 
1603 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
1604 		struct vport *vport;
1605 		struct hlist_node *n;
1606 
1607 		hlist_for_each_entry_safe(vport, n, &dp->ports[i], dp_hash_node)
1608 			if (vport->port_no != OVSP_LOCAL)
1609 				ovs_dp_detach_port(vport);
1610 	}
1611 
1612 	list_del_rcu(&dp->list_node);
1613 
1614 	/* OVSP_LOCAL is datapath internal port. We need to make sure that
1615 	 * all ports in datapath are destroyed first before freeing datapath.
1616 	 */
1617 	ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
1618 
1619 	/* RCU destroy the flow table */
1620 	call_rcu(&dp->rcu, destroy_dp_rcu);
1621 }
1622 
1623 static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
1624 {
1625 	struct sk_buff *reply;
1626 	struct datapath *dp;
1627 	int err;
1628 
1629 	reply = ovs_dp_cmd_alloc_info(info);
1630 	if (!reply)
1631 		return -ENOMEM;
1632 
1633 	ovs_lock();
1634 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1635 	err = PTR_ERR(dp);
1636 	if (IS_ERR(dp))
1637 		goto err_unlock_free;
1638 
1639 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1640 				   info->snd_seq, 0, OVS_DP_CMD_DEL);
1641 	BUG_ON(err < 0);
1642 
1643 	__dp_destroy(dp);
1644 	ovs_unlock();
1645 
1646 	ovs_notify(&dp_datapath_genl_family, reply, info);
1647 
1648 	return 0;
1649 
1650 err_unlock_free:
1651 	ovs_unlock();
1652 	kfree_skb(reply);
1653 	return err;
1654 }
1655 
1656 static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
1657 {
1658 	struct sk_buff *reply;
1659 	struct datapath *dp;
1660 	int err;
1661 
1662 	reply = ovs_dp_cmd_alloc_info(info);
1663 	if (!reply)
1664 		return -ENOMEM;
1665 
1666 	ovs_lock();
1667 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1668 	err = PTR_ERR(dp);
1669 	if (IS_ERR(dp))
1670 		goto err_unlock_free;
1671 
1672 	ovs_dp_change(dp, info->attrs);
1673 
1674 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1675 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1676 	BUG_ON(err < 0);
1677 
1678 	ovs_unlock();
1679 	ovs_notify(&dp_datapath_genl_family, reply, info);
1680 
1681 	return 0;
1682 
1683 err_unlock_free:
1684 	ovs_unlock();
1685 	kfree_skb(reply);
1686 	return err;
1687 }
1688 
1689 static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
1690 {
1691 	struct sk_buff *reply;
1692 	struct datapath *dp;
1693 	int err;
1694 
1695 	reply = ovs_dp_cmd_alloc_info(info);
1696 	if (!reply)
1697 		return -ENOMEM;
1698 
1699 	ovs_lock();
1700 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1701 	if (IS_ERR(dp)) {
1702 		err = PTR_ERR(dp);
1703 		goto err_unlock_free;
1704 	}
1705 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1706 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1707 	BUG_ON(err < 0);
1708 	ovs_unlock();
1709 
1710 	return genlmsg_reply(reply, info);
1711 
1712 err_unlock_free:
1713 	ovs_unlock();
1714 	kfree_skb(reply);
1715 	return err;
1716 }
1717 
1718 static int ovs_dp_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1719 {
1720 	struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
1721 	struct datapath *dp;
1722 	int skip = cb->args[0];
1723 	int i = 0;
1724 
1725 	ovs_lock();
1726 	list_for_each_entry(dp, &ovs_net->dps, list_node) {
1727 		if (i >= skip &&
1728 		    ovs_dp_cmd_fill_info(dp, skb, NETLINK_CB(cb->skb).portid,
1729 					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1730 					 OVS_DP_CMD_NEW) < 0)
1731 			break;
1732 		i++;
1733 	}
1734 	ovs_unlock();
1735 
1736 	cb->args[0] = i;
1737 
1738 	return skb->len;
1739 }
1740 
1741 static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
1742 	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1743 	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1744 	[OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 },
1745 };
1746 
1747 static const struct genl_ops dp_datapath_genl_ops[] = {
1748 	{ .cmd = OVS_DP_CMD_NEW,
1749 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1750 	  .policy = datapath_policy,
1751 	  .doit = ovs_dp_cmd_new
1752 	},
1753 	{ .cmd = OVS_DP_CMD_DEL,
1754 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1755 	  .policy = datapath_policy,
1756 	  .doit = ovs_dp_cmd_del
1757 	},
1758 	{ .cmd = OVS_DP_CMD_GET,
1759 	  .flags = 0,		    /* OK for unprivileged users. */
1760 	  .policy = datapath_policy,
1761 	  .doit = ovs_dp_cmd_get,
1762 	  .dumpit = ovs_dp_cmd_dump
1763 	},
1764 	{ .cmd = OVS_DP_CMD_SET,
1765 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1766 	  .policy = datapath_policy,
1767 	  .doit = ovs_dp_cmd_set,
1768 	},
1769 };
1770 
1771 static struct genl_family dp_datapath_genl_family = {
1772 	.id = GENL_ID_GENERATE,
1773 	.hdrsize = sizeof(struct ovs_header),
1774 	.name = OVS_DATAPATH_FAMILY,
1775 	.version = OVS_DATAPATH_VERSION,
1776 	.maxattr = OVS_DP_ATTR_MAX,
1777 	.netnsok = true,
1778 	.parallel_ops = true,
1779 	.ops = dp_datapath_genl_ops,
1780 	.n_ops = ARRAY_SIZE(dp_datapath_genl_ops),
1781 	.mcgrps = &ovs_dp_datapath_multicast_group,
1782 	.n_mcgrps = 1,
1783 };
1784 
1785 /* Called with ovs_mutex or RCU read lock. */
1786 static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
1787 				   u32 portid, u32 seq, u32 flags, u8 cmd)
1788 {
1789 	struct ovs_header *ovs_header;
1790 	struct ovs_vport_stats vport_stats;
1791 	int err;
1792 
1793 	ovs_header = genlmsg_put(skb, portid, seq, &dp_vport_genl_family,
1794 				 flags, cmd);
1795 	if (!ovs_header)
1796 		return -EMSGSIZE;
1797 
1798 	ovs_header->dp_ifindex = get_dpifindex(vport->dp);
1799 
1800 	if (nla_put_u32(skb, OVS_VPORT_ATTR_PORT_NO, vport->port_no) ||
1801 	    nla_put_u32(skb, OVS_VPORT_ATTR_TYPE, vport->ops->type) ||
1802 	    nla_put_string(skb, OVS_VPORT_ATTR_NAME,
1803 			   vport->ops->get_name(vport)))
1804 		goto nla_put_failure;
1805 
1806 	ovs_vport_get_stats(vport, &vport_stats);
1807 	if (nla_put(skb, OVS_VPORT_ATTR_STATS, sizeof(struct ovs_vport_stats),
1808 		    &vport_stats))
1809 		goto nla_put_failure;
1810 
1811 	if (ovs_vport_get_upcall_portids(vport, skb))
1812 		goto nla_put_failure;
1813 
1814 	err = ovs_vport_get_options(vport, skb);
1815 	if (err == -EMSGSIZE)
1816 		goto error;
1817 
1818 	genlmsg_end(skb, ovs_header);
1819 	return 0;
1820 
1821 nla_put_failure:
1822 	err = -EMSGSIZE;
1823 error:
1824 	genlmsg_cancel(skb, ovs_header);
1825 	return err;
1826 }
1827 
1828 static struct sk_buff *ovs_vport_cmd_alloc_info(void)
1829 {
1830 	return nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1831 }
1832 
1833 /* Called with ovs_mutex, only via ovs_dp_notify_wq(). */
1834 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, u32 portid,
1835 					 u32 seq, u8 cmd)
1836 {
1837 	struct sk_buff *skb;
1838 	int retval;
1839 
1840 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1841 	if (!skb)
1842 		return ERR_PTR(-ENOMEM);
1843 
1844 	retval = ovs_vport_cmd_fill_info(vport, skb, portid, seq, 0, cmd);
1845 	BUG_ON(retval < 0);
1846 
1847 	return skb;
1848 }
1849 
1850 /* Called with ovs_mutex or RCU read lock. */
1851 static struct vport *lookup_vport(struct net *net,
1852 				  const struct ovs_header *ovs_header,
1853 				  struct nlattr *a[OVS_VPORT_ATTR_MAX + 1])
1854 {
1855 	struct datapath *dp;
1856 	struct vport *vport;
1857 
1858 	if (a[OVS_VPORT_ATTR_NAME]) {
1859 		vport = ovs_vport_locate(net, nla_data(a[OVS_VPORT_ATTR_NAME]));
1860 		if (!vport)
1861 			return ERR_PTR(-ENODEV);
1862 		if (ovs_header->dp_ifindex &&
1863 		    ovs_header->dp_ifindex != get_dpifindex(vport->dp))
1864 			return ERR_PTR(-ENODEV);
1865 		return vport;
1866 	} else if (a[OVS_VPORT_ATTR_PORT_NO]) {
1867 		u32 port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
1868 
1869 		if (port_no >= DP_MAX_PORTS)
1870 			return ERR_PTR(-EFBIG);
1871 
1872 		dp = get_dp(net, ovs_header->dp_ifindex);
1873 		if (!dp)
1874 			return ERR_PTR(-ENODEV);
1875 
1876 		vport = ovs_vport_ovsl_rcu(dp, port_no);
1877 		if (!vport)
1878 			return ERR_PTR(-ENODEV);
1879 		return vport;
1880 	} else
1881 		return ERR_PTR(-EINVAL);
1882 }
1883 
1884 static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
1885 {
1886 	struct nlattr **a = info->attrs;
1887 	struct ovs_header *ovs_header = info->userhdr;
1888 	struct vport_parms parms;
1889 	struct sk_buff *reply;
1890 	struct vport *vport;
1891 	struct datapath *dp;
1892 	u32 port_no;
1893 	int err;
1894 
1895 	if (!a[OVS_VPORT_ATTR_NAME] || !a[OVS_VPORT_ATTR_TYPE] ||
1896 	    !a[OVS_VPORT_ATTR_UPCALL_PID])
1897 		return -EINVAL;
1898 
1899 	port_no = a[OVS_VPORT_ATTR_PORT_NO]
1900 		? nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]) : 0;
1901 	if (port_no >= DP_MAX_PORTS)
1902 		return -EFBIG;
1903 
1904 	reply = ovs_vport_cmd_alloc_info();
1905 	if (!reply)
1906 		return -ENOMEM;
1907 
1908 	ovs_lock();
1909 restart:
1910 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1911 	err = -ENODEV;
1912 	if (!dp)
1913 		goto exit_unlock_free;
1914 
1915 	if (port_no) {
1916 		vport = ovs_vport_ovsl(dp, port_no);
1917 		err = -EBUSY;
1918 		if (vport)
1919 			goto exit_unlock_free;
1920 	} else {
1921 		for (port_no = 1; ; port_no++) {
1922 			if (port_no >= DP_MAX_PORTS) {
1923 				err = -EFBIG;
1924 				goto exit_unlock_free;
1925 			}
1926 			vport = ovs_vport_ovsl(dp, port_no);
1927 			if (!vport)
1928 				break;
1929 		}
1930 	}
1931 
1932 	parms.name = nla_data(a[OVS_VPORT_ATTR_NAME]);
1933 	parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
1934 	parms.options = a[OVS_VPORT_ATTR_OPTIONS];
1935 	parms.dp = dp;
1936 	parms.port_no = port_no;
1937 	parms.upcall_portids = a[OVS_VPORT_ATTR_UPCALL_PID];
1938 
1939 	vport = new_vport(&parms);
1940 	err = PTR_ERR(vport);
1941 	if (IS_ERR(vport)) {
1942 		if (err == -EAGAIN)
1943 			goto restart;
1944 		goto exit_unlock_free;
1945 	}
1946 
1947 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1948 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
1949 	BUG_ON(err < 0);
1950 	ovs_unlock();
1951 
1952 	ovs_notify(&dp_vport_genl_family, reply, info);
1953 	return 0;
1954 
1955 exit_unlock_free:
1956 	ovs_unlock();
1957 	kfree_skb(reply);
1958 	return err;
1959 }
1960 
1961 static int ovs_vport_cmd_set(struct sk_buff *skb, struct genl_info *info)
1962 {
1963 	struct nlattr **a = info->attrs;
1964 	struct sk_buff *reply;
1965 	struct vport *vport;
1966 	int err;
1967 
1968 	reply = ovs_vport_cmd_alloc_info();
1969 	if (!reply)
1970 		return -ENOMEM;
1971 
1972 	ovs_lock();
1973 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
1974 	err = PTR_ERR(vport);
1975 	if (IS_ERR(vport))
1976 		goto exit_unlock_free;
1977 
1978 	if (a[OVS_VPORT_ATTR_TYPE] &&
1979 	    nla_get_u32(a[OVS_VPORT_ATTR_TYPE]) != vport->ops->type) {
1980 		err = -EINVAL;
1981 		goto exit_unlock_free;
1982 	}
1983 
1984 	if (a[OVS_VPORT_ATTR_OPTIONS]) {
1985 		err = ovs_vport_set_options(vport, a[OVS_VPORT_ATTR_OPTIONS]);
1986 		if (err)
1987 			goto exit_unlock_free;
1988 	}
1989 
1990 
1991 	if (a[OVS_VPORT_ATTR_UPCALL_PID]) {
1992 		struct nlattr *ids = a[OVS_VPORT_ATTR_UPCALL_PID];
1993 
1994 		err = ovs_vport_set_upcall_portids(vport, ids);
1995 		if (err)
1996 			goto exit_unlock_free;
1997 	}
1998 
1999 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2000 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
2001 	BUG_ON(err < 0);
2002 
2003 	ovs_unlock();
2004 	ovs_notify(&dp_vport_genl_family, reply, info);
2005 	return 0;
2006 
2007 exit_unlock_free:
2008 	ovs_unlock();
2009 	kfree_skb(reply);
2010 	return err;
2011 }
2012 
2013 static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info)
2014 {
2015 	struct nlattr **a = info->attrs;
2016 	struct sk_buff *reply;
2017 	struct vport *vport;
2018 	int err;
2019 
2020 	reply = ovs_vport_cmd_alloc_info();
2021 	if (!reply)
2022 		return -ENOMEM;
2023 
2024 	ovs_lock();
2025 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
2026 	err = PTR_ERR(vport);
2027 	if (IS_ERR(vport))
2028 		goto exit_unlock_free;
2029 
2030 	if (vport->port_no == OVSP_LOCAL) {
2031 		err = -EINVAL;
2032 		goto exit_unlock_free;
2033 	}
2034 
2035 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2036 				      info->snd_seq, 0, OVS_VPORT_CMD_DEL);
2037 	BUG_ON(err < 0);
2038 	ovs_dp_detach_port(vport);
2039 	ovs_unlock();
2040 
2041 	ovs_notify(&dp_vport_genl_family, reply, info);
2042 	return 0;
2043 
2044 exit_unlock_free:
2045 	ovs_unlock();
2046 	kfree_skb(reply);
2047 	return err;
2048 }
2049 
2050 static int ovs_vport_cmd_get(struct sk_buff *skb, struct genl_info *info)
2051 {
2052 	struct nlattr **a = info->attrs;
2053 	struct ovs_header *ovs_header = info->userhdr;
2054 	struct sk_buff *reply;
2055 	struct vport *vport;
2056 	int err;
2057 
2058 	reply = ovs_vport_cmd_alloc_info();
2059 	if (!reply)
2060 		return -ENOMEM;
2061 
2062 	rcu_read_lock();
2063 	vport = lookup_vport(sock_net(skb->sk), ovs_header, a);
2064 	err = PTR_ERR(vport);
2065 	if (IS_ERR(vport))
2066 		goto exit_unlock_free;
2067 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2068 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
2069 	BUG_ON(err < 0);
2070 	rcu_read_unlock();
2071 
2072 	return genlmsg_reply(reply, info);
2073 
2074 exit_unlock_free:
2075 	rcu_read_unlock();
2076 	kfree_skb(reply);
2077 	return err;
2078 }
2079 
2080 static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
2081 {
2082 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
2083 	struct datapath *dp;
2084 	int bucket = cb->args[0], skip = cb->args[1];
2085 	int i, j = 0;
2086 
2087 	rcu_read_lock();
2088 	dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex);
2089 	if (!dp) {
2090 		rcu_read_unlock();
2091 		return -ENODEV;
2092 	}
2093 	for (i = bucket; i < DP_VPORT_HASH_BUCKETS; i++) {
2094 		struct vport *vport;
2095 
2096 		j = 0;
2097 		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) {
2098 			if (j >= skip &&
2099 			    ovs_vport_cmd_fill_info(vport, skb,
2100 						    NETLINK_CB(cb->skb).portid,
2101 						    cb->nlh->nlmsg_seq,
2102 						    NLM_F_MULTI,
2103 						    OVS_VPORT_CMD_NEW) < 0)
2104 				goto out;
2105 
2106 			j++;
2107 		}
2108 		skip = 0;
2109 	}
2110 out:
2111 	rcu_read_unlock();
2112 
2113 	cb->args[0] = i;
2114 	cb->args[1] = j;
2115 
2116 	return skb->len;
2117 }
2118 
2119 static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
2120 	[OVS_VPORT_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
2121 	[OVS_VPORT_ATTR_STATS] = { .len = sizeof(struct ovs_vport_stats) },
2122 	[OVS_VPORT_ATTR_PORT_NO] = { .type = NLA_U32 },
2123 	[OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 },
2124 	[OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_U32 },
2125 	[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
2126 };
2127 
2128 static const struct genl_ops dp_vport_genl_ops[] = {
2129 	{ .cmd = OVS_VPORT_CMD_NEW,
2130 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2131 	  .policy = vport_policy,
2132 	  .doit = ovs_vport_cmd_new
2133 	},
2134 	{ .cmd = OVS_VPORT_CMD_DEL,
2135 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2136 	  .policy = vport_policy,
2137 	  .doit = ovs_vport_cmd_del
2138 	},
2139 	{ .cmd = OVS_VPORT_CMD_GET,
2140 	  .flags = 0,		    /* OK for unprivileged users. */
2141 	  .policy = vport_policy,
2142 	  .doit = ovs_vport_cmd_get,
2143 	  .dumpit = ovs_vport_cmd_dump
2144 	},
2145 	{ .cmd = OVS_VPORT_CMD_SET,
2146 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2147 	  .policy = vport_policy,
2148 	  .doit = ovs_vport_cmd_set,
2149 	},
2150 };
2151 
2152 struct genl_family dp_vport_genl_family = {
2153 	.id = GENL_ID_GENERATE,
2154 	.hdrsize = sizeof(struct ovs_header),
2155 	.name = OVS_VPORT_FAMILY,
2156 	.version = OVS_VPORT_VERSION,
2157 	.maxattr = OVS_VPORT_ATTR_MAX,
2158 	.netnsok = true,
2159 	.parallel_ops = true,
2160 	.ops = dp_vport_genl_ops,
2161 	.n_ops = ARRAY_SIZE(dp_vport_genl_ops),
2162 	.mcgrps = &ovs_dp_vport_multicast_group,
2163 	.n_mcgrps = 1,
2164 };
2165 
2166 static struct genl_family * const dp_genl_families[] = {
2167 	&dp_datapath_genl_family,
2168 	&dp_vport_genl_family,
2169 	&dp_flow_genl_family,
2170 	&dp_packet_genl_family,
2171 };
2172 
2173 static void dp_unregister_genl(int n_families)
2174 {
2175 	int i;
2176 
2177 	for (i = 0; i < n_families; i++)
2178 		genl_unregister_family(dp_genl_families[i]);
2179 }
2180 
2181 static int dp_register_genl(void)
2182 {
2183 	int err;
2184 	int i;
2185 
2186 	for (i = 0; i < ARRAY_SIZE(dp_genl_families); i++) {
2187 
2188 		err = genl_register_family(dp_genl_families[i]);
2189 		if (err)
2190 			goto error;
2191 	}
2192 
2193 	return 0;
2194 
2195 error:
2196 	dp_unregister_genl(i);
2197 	return err;
2198 }
2199 
2200 static int __net_init ovs_init_net(struct net *net)
2201 {
2202 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2203 
2204 	INIT_LIST_HEAD(&ovs_net->dps);
2205 	INIT_WORK(&ovs_net->dp_notify_work, ovs_dp_notify_wq);
2206 	return 0;
2207 }
2208 
2209 static void __net_exit list_vports_from_net(struct net *net, struct net *dnet,
2210 					    struct list_head *head)
2211 {
2212 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2213 	struct datapath *dp;
2214 
2215 	list_for_each_entry(dp, &ovs_net->dps, list_node) {
2216 		int i;
2217 
2218 		for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
2219 			struct vport *vport;
2220 
2221 			hlist_for_each_entry(vport, &dp->ports[i], dp_hash_node) {
2222 				struct netdev_vport *netdev_vport;
2223 
2224 				if (vport->ops->type != OVS_VPORT_TYPE_INTERNAL)
2225 					continue;
2226 
2227 				netdev_vport = netdev_vport_priv(vport);
2228 				if (dev_net(netdev_vport->dev) == dnet)
2229 					list_add(&vport->detach_list, head);
2230 			}
2231 		}
2232 	}
2233 }
2234 
2235 static void __net_exit ovs_exit_net(struct net *dnet)
2236 {
2237 	struct datapath *dp, *dp_next;
2238 	struct ovs_net *ovs_net = net_generic(dnet, ovs_net_id);
2239 	struct vport *vport, *vport_next;
2240 	struct net *net;
2241 	LIST_HEAD(head);
2242 
2243 	ovs_lock();
2244 	list_for_each_entry_safe(dp, dp_next, &ovs_net->dps, list_node)
2245 		__dp_destroy(dp);
2246 
2247 	rtnl_lock();
2248 	for_each_net(net)
2249 		list_vports_from_net(net, dnet, &head);
2250 	rtnl_unlock();
2251 
2252 	/* Detach all vports from given namespace. */
2253 	list_for_each_entry_safe(vport, vport_next, &head, detach_list) {
2254 		list_del(&vport->detach_list);
2255 		ovs_dp_detach_port(vport);
2256 	}
2257 
2258 	ovs_unlock();
2259 
2260 	cancel_work_sync(&ovs_net->dp_notify_work);
2261 }
2262 
2263 static struct pernet_operations ovs_net_ops = {
2264 	.init = ovs_init_net,
2265 	.exit = ovs_exit_net,
2266 	.id   = &ovs_net_id,
2267 	.size = sizeof(struct ovs_net),
2268 };
2269 
2270 static int __init dp_init(void)
2271 {
2272 	int err;
2273 
2274 	BUILD_BUG_ON(sizeof(struct ovs_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb));
2275 
2276 	pr_info("Open vSwitch switching datapath\n");
2277 
2278 	err = action_fifos_init();
2279 	if (err)
2280 		goto error;
2281 
2282 	err = ovs_internal_dev_rtnl_link_register();
2283 	if (err)
2284 		goto error_action_fifos_exit;
2285 
2286 	err = ovs_flow_init();
2287 	if (err)
2288 		goto error_unreg_rtnl_link;
2289 
2290 	err = ovs_vport_init();
2291 	if (err)
2292 		goto error_flow_exit;
2293 
2294 	err = register_pernet_device(&ovs_net_ops);
2295 	if (err)
2296 		goto error_vport_exit;
2297 
2298 	err = register_netdevice_notifier(&ovs_dp_device_notifier);
2299 	if (err)
2300 		goto error_netns_exit;
2301 
2302 	err = ovs_netdev_init();
2303 	if (err)
2304 		goto error_unreg_notifier;
2305 
2306 	err = dp_register_genl();
2307 	if (err < 0)
2308 		goto error_unreg_netdev;
2309 
2310 	return 0;
2311 
2312 error_unreg_netdev:
2313 	ovs_netdev_exit();
2314 error_unreg_notifier:
2315 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2316 error_netns_exit:
2317 	unregister_pernet_device(&ovs_net_ops);
2318 error_vport_exit:
2319 	ovs_vport_exit();
2320 error_flow_exit:
2321 	ovs_flow_exit();
2322 error_unreg_rtnl_link:
2323 	ovs_internal_dev_rtnl_link_unregister();
2324 error_action_fifos_exit:
2325 	action_fifos_exit();
2326 error:
2327 	return err;
2328 }
2329 
2330 static void dp_cleanup(void)
2331 {
2332 	dp_unregister_genl(ARRAY_SIZE(dp_genl_families));
2333 	ovs_netdev_exit();
2334 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2335 	unregister_pernet_device(&ovs_net_ops);
2336 	rcu_barrier();
2337 	ovs_vport_exit();
2338 	ovs_flow_exit();
2339 	ovs_internal_dev_rtnl_link_unregister();
2340 	action_fifos_exit();
2341 }
2342 
2343 module_init(dp_init);
2344 module_exit(dp_cleanup);
2345 
2346 MODULE_DESCRIPTION("Open vSwitch switching datapath");
2347 MODULE_LICENSE("GPL");
2348