xref: /linux/net/openvswitch/datapath.c (revision cd2a9e62c8a3c5cae7691982667d79a0edc65283)
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, info, 0, GFP_KERNEL);
95 }
96 
97 /**
98  * DOC: Locking:
99  *
100  * All writes e.g. Writes to device state (add/remove datapath, port, set
101  * operations on vports, etc.), Writes to other state (flow table
102  * modifications, set miscellaneous datapath parameters, etc.) are protected
103  * by ovs_lock.
104  *
105  * Reads are protected by RCU.
106  *
107  * There are a few special cases (mostly stats) that have their own
108  * synchronization but they nest under all of above and don't interact with
109  * each other.
110  *
111  * The RTNL lock nests inside ovs_mutex.
112  */
113 
114 static DEFINE_MUTEX(ovs_mutex);
115 
116 void ovs_lock(void)
117 {
118 	mutex_lock(&ovs_mutex);
119 }
120 
121 void ovs_unlock(void)
122 {
123 	mutex_unlock(&ovs_mutex);
124 }
125 
126 #ifdef CONFIG_LOCKDEP
127 int lockdep_ovsl_is_held(void)
128 {
129 	if (debug_locks)
130 		return lockdep_is_held(&ovs_mutex);
131 	else
132 		return 1;
133 }
134 EXPORT_SYMBOL_GPL(lockdep_ovsl_is_held);
135 #endif
136 
137 static struct vport *new_vport(const struct vport_parms *);
138 static int queue_gso_packets(struct datapath *dp, struct sk_buff *,
139 			     const struct sw_flow_key *,
140 			     const struct dp_upcall_info *,
141 			     uint32_t cutlen);
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 				  uint32_t cutlen);
146 
147 /* Must be called with rcu_read_lock. */
148 static struct datapath *get_dp_rcu(struct net *net, int dp_ifindex)
149 {
150 	struct net_device *dev = dev_get_by_index_rcu(net, dp_ifindex);
151 
152 	if (dev) {
153 		struct vport *vport = ovs_internal_dev_get_vport(dev);
154 		if (vport)
155 			return vport->dp;
156 	}
157 
158 	return NULL;
159 }
160 
161 /* The caller must hold either ovs_mutex or rcu_read_lock to keep the
162  * returned dp pointer valid.
163  */
164 static inline struct datapath *get_dp(struct net *net, int dp_ifindex)
165 {
166 	struct datapath *dp;
167 
168 	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held());
169 	rcu_read_lock();
170 	dp = get_dp_rcu(net, dp_ifindex);
171 	rcu_read_unlock();
172 
173 	return dp;
174 }
175 
176 /* Must be called with rcu_read_lock or ovs_mutex. */
177 const char *ovs_dp_name(const struct datapath *dp)
178 {
179 	struct vport *vport = ovs_vport_ovsl_rcu(dp, OVSP_LOCAL);
180 	return ovs_vport_name(vport);
181 }
182 
183 static int get_dpifindex(const struct datapath *dp)
184 {
185 	struct vport *local;
186 	int ifindex;
187 
188 	rcu_read_lock();
189 
190 	local = ovs_vport_rcu(dp, OVSP_LOCAL);
191 	if (local)
192 		ifindex = local->dev->ifindex;
193 	else
194 		ifindex = 0;
195 
196 	rcu_read_unlock();
197 
198 	return ifindex;
199 }
200 
201 static void destroy_dp_rcu(struct rcu_head *rcu)
202 {
203 	struct datapath *dp = container_of(rcu, struct datapath, rcu);
204 
205 	ovs_flow_tbl_destroy(&dp->table);
206 	free_percpu(dp->stats_percpu);
207 	kfree(dp->ports);
208 	kfree(dp);
209 }
210 
211 static struct hlist_head *vport_hash_bucket(const struct datapath *dp,
212 					    u16 port_no)
213 {
214 	return &dp->ports[port_no & (DP_VPORT_HASH_BUCKETS - 1)];
215 }
216 
217 /* Called with ovs_mutex or RCU read lock. */
218 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no)
219 {
220 	struct vport *vport;
221 	struct hlist_head *head;
222 
223 	head = vport_hash_bucket(dp, port_no);
224 	hlist_for_each_entry_rcu(vport, head, dp_hash_node) {
225 		if (vport->port_no == port_no)
226 			return vport;
227 	}
228 	return NULL;
229 }
230 
231 /* Called with ovs_mutex. */
232 static struct vport *new_vport(const struct vport_parms *parms)
233 {
234 	struct vport *vport;
235 
236 	vport = ovs_vport_add(parms);
237 	if (!IS_ERR(vport)) {
238 		struct datapath *dp = parms->dp;
239 		struct hlist_head *head = vport_hash_bucket(dp, vport->port_no);
240 
241 		hlist_add_head_rcu(&vport->dp_hash_node, head);
242 	}
243 	return vport;
244 }
245 
246 void ovs_dp_detach_port(struct vport *p)
247 {
248 	ASSERT_OVSL();
249 
250 	/* First drop references to device. */
251 	hlist_del_rcu(&p->dp_hash_node);
252 
253 	/* Then destroy it. */
254 	ovs_vport_del(p);
255 }
256 
257 /* Must be called with rcu_read_lock. */
258 void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key)
259 {
260 	const struct vport *p = OVS_CB(skb)->input_vport;
261 	struct datapath *dp = p->dp;
262 	struct sw_flow *flow;
263 	struct sw_flow_actions *sf_acts;
264 	struct dp_stats_percpu *stats;
265 	u64 *stats_counter;
266 	u32 n_mask_hit;
267 
268 	stats = this_cpu_ptr(dp->stats_percpu);
269 
270 	/* Look up flow. */
271 	flow = ovs_flow_tbl_lookup_stats(&dp->table, key, &n_mask_hit);
272 	if (unlikely(!flow)) {
273 		struct dp_upcall_info upcall;
274 		int error;
275 
276 		memset(&upcall, 0, sizeof(upcall));
277 		upcall.cmd = OVS_PACKET_CMD_MISS;
278 		upcall.portid = ovs_vport_find_upcall_portid(p, skb);
279 		upcall.mru = OVS_CB(skb)->mru;
280 		error = ovs_dp_upcall(dp, skb, key, &upcall, 0);
281 		if (unlikely(error))
282 			kfree_skb(skb);
283 		else
284 			consume_skb(skb);
285 		stats_counter = &stats->n_missed;
286 		goto out;
287 	}
288 
289 	ovs_flow_stats_update(flow, key->tp.flags, skb);
290 	sf_acts = rcu_dereference(flow->sf_acts);
291 	ovs_execute_actions(dp, skb, sf_acts, key);
292 
293 	stats_counter = &stats->n_hit;
294 
295 out:
296 	/* Update datapath statistics. */
297 	u64_stats_update_begin(&stats->syncp);
298 	(*stats_counter)++;
299 	stats->n_mask_hit += n_mask_hit;
300 	u64_stats_update_end(&stats->syncp);
301 }
302 
303 int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
304 		  const struct sw_flow_key *key,
305 		  const struct dp_upcall_info *upcall_info,
306 		  uint32_t cutlen)
307 {
308 	struct dp_stats_percpu *stats;
309 	int err;
310 
311 	if (upcall_info->portid == 0) {
312 		err = -ENOTCONN;
313 		goto err;
314 	}
315 
316 	if (!skb_is_gso(skb))
317 		err = queue_userspace_packet(dp, skb, key, upcall_info, cutlen);
318 	else
319 		err = queue_gso_packets(dp, skb, key, upcall_info, cutlen);
320 	if (err)
321 		goto err;
322 
323 	return 0;
324 
325 err:
326 	stats = this_cpu_ptr(dp->stats_percpu);
327 
328 	u64_stats_update_begin(&stats->syncp);
329 	stats->n_lost++;
330 	u64_stats_update_end(&stats->syncp);
331 
332 	return err;
333 }
334 
335 static int queue_gso_packets(struct datapath *dp, struct sk_buff *skb,
336 			     const struct sw_flow_key *key,
337 			     const struct dp_upcall_info *upcall_info,
338 				 uint32_t cutlen)
339 {
340 	unsigned short gso_type = skb_shinfo(skb)->gso_type;
341 	struct sw_flow_key later_key;
342 	struct sk_buff *segs, *nskb;
343 	int err;
344 
345 	BUILD_BUG_ON(sizeof(*OVS_CB(skb)) > SKB_SGO_CB_OFFSET);
346 	segs = __skb_gso_segment(skb, NETIF_F_SG, false);
347 	if (IS_ERR(segs))
348 		return PTR_ERR(segs);
349 	if (segs == NULL)
350 		return -EINVAL;
351 
352 	if (gso_type & SKB_GSO_UDP) {
353 		/* The initial flow key extracted by ovs_flow_key_extract()
354 		 * in this case is for a first fragment, so we need to
355 		 * properly mark later fragments.
356 		 */
357 		later_key = *key;
358 		later_key.ip.frag = OVS_FRAG_TYPE_LATER;
359 	}
360 
361 	/* Queue all of the segments. */
362 	skb = segs;
363 	do {
364 		if (gso_type & SKB_GSO_UDP && skb != segs)
365 			key = &later_key;
366 
367 		err = queue_userspace_packet(dp, skb, key, upcall_info, cutlen);
368 		if (err)
369 			break;
370 
371 	} while ((skb = skb->next));
372 
373 	/* Free all of the segments. */
374 	skb = segs;
375 	do {
376 		nskb = skb->next;
377 		if (err)
378 			kfree_skb(skb);
379 		else
380 			consume_skb(skb);
381 	} while ((skb = nskb));
382 	return err;
383 }
384 
385 static size_t upcall_msg_size(const struct dp_upcall_info *upcall_info,
386 			      unsigned int hdrlen)
387 {
388 	size_t size = NLMSG_ALIGN(sizeof(struct ovs_header))
389 		+ nla_total_size(hdrlen) /* OVS_PACKET_ATTR_PACKET */
390 		+ nla_total_size(ovs_key_attr_size()); /* OVS_PACKET_ATTR_KEY */
391 
392 	/* OVS_PACKET_ATTR_USERDATA */
393 	if (upcall_info->userdata)
394 		size += NLA_ALIGN(upcall_info->userdata->nla_len);
395 
396 	/* OVS_PACKET_ATTR_EGRESS_TUN_KEY */
397 	if (upcall_info->egress_tun_info)
398 		size += nla_total_size(ovs_tun_key_attr_size());
399 
400 	/* OVS_PACKET_ATTR_ACTIONS */
401 	if (upcall_info->actions_len)
402 		size += nla_total_size(upcall_info->actions_len);
403 
404 	/* OVS_PACKET_ATTR_MRU */
405 	if (upcall_info->mru)
406 		size += nla_total_size(sizeof(upcall_info->mru));
407 
408 	return size;
409 }
410 
411 static void pad_packet(struct datapath *dp, struct sk_buff *skb)
412 {
413 	if (!(dp->user_features & OVS_DP_F_UNALIGNED)) {
414 		size_t plen = NLA_ALIGN(skb->len) - skb->len;
415 
416 		if (plen > 0)
417 			memset(skb_put(skb, plen), 0, plen);
418 	}
419 }
420 
421 static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
422 				  const struct sw_flow_key *key,
423 				  const struct dp_upcall_info *upcall_info,
424 				  uint32_t cutlen)
425 {
426 	struct ovs_header *upcall;
427 	struct sk_buff *nskb = NULL;
428 	struct sk_buff *user_skb = NULL; /* to be queued to userspace */
429 	struct nlattr *nla;
430 	size_t len;
431 	unsigned int hlen;
432 	int err, dp_ifindex;
433 
434 	dp_ifindex = get_dpifindex(dp);
435 	if (!dp_ifindex)
436 		return -ENODEV;
437 
438 	if (skb_vlan_tag_present(skb)) {
439 		nskb = skb_clone(skb, GFP_ATOMIC);
440 		if (!nskb)
441 			return -ENOMEM;
442 
443 		nskb = __vlan_hwaccel_push_inside(nskb);
444 		if (!nskb)
445 			return -ENOMEM;
446 
447 		skb = nskb;
448 	}
449 
450 	if (nla_attr_size(skb->len) > USHRT_MAX) {
451 		err = -EFBIG;
452 		goto out;
453 	}
454 
455 	/* Complete checksum if needed */
456 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
457 	    (err = skb_checksum_help(skb)))
458 		goto out;
459 
460 	/* Older versions of OVS user space enforce alignment of the last
461 	 * Netlink attribute to NLA_ALIGNTO which would require extensive
462 	 * padding logic. Only perform zerocopy if padding is not required.
463 	 */
464 	if (dp->user_features & OVS_DP_F_UNALIGNED)
465 		hlen = skb_zerocopy_headlen(skb);
466 	else
467 		hlen = skb->len;
468 
469 	len = upcall_msg_size(upcall_info, hlen - cutlen);
470 	user_skb = genlmsg_new(len, GFP_ATOMIC);
471 	if (!user_skb) {
472 		err = -ENOMEM;
473 		goto out;
474 	}
475 
476 	upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
477 			     0, upcall_info->cmd);
478 	upcall->dp_ifindex = dp_ifindex;
479 
480 	err = ovs_nla_put_key(key, key, OVS_PACKET_ATTR_KEY, false, user_skb);
481 	BUG_ON(err);
482 
483 	if (upcall_info->userdata)
484 		__nla_put(user_skb, OVS_PACKET_ATTR_USERDATA,
485 			  nla_len(upcall_info->userdata),
486 			  nla_data(upcall_info->userdata));
487 
488 	if (upcall_info->egress_tun_info) {
489 		nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_EGRESS_TUN_KEY);
490 		err = ovs_nla_put_tunnel_info(user_skb,
491 					      upcall_info->egress_tun_info);
492 		BUG_ON(err);
493 		nla_nest_end(user_skb, nla);
494 	}
495 
496 	if (upcall_info->actions_len) {
497 		nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_ACTIONS);
498 		err = ovs_nla_put_actions(upcall_info->actions,
499 					  upcall_info->actions_len,
500 					  user_skb);
501 		if (!err)
502 			nla_nest_end(user_skb, nla);
503 		else
504 			nla_nest_cancel(user_skb, nla);
505 	}
506 
507 	/* Add OVS_PACKET_ATTR_MRU */
508 	if (upcall_info->mru) {
509 		if (nla_put_u16(user_skb, OVS_PACKET_ATTR_MRU,
510 				upcall_info->mru)) {
511 			err = -ENOBUFS;
512 			goto out;
513 		}
514 		pad_packet(dp, user_skb);
515 	}
516 
517 	/* Only reserve room for attribute header, packet data is added
518 	 * in skb_zerocopy() */
519 	if (!(nla = nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, 0))) {
520 		err = -ENOBUFS;
521 		goto out;
522 	}
523 	nla->nla_len = nla_attr_size(skb->len - cutlen);
524 
525 	err = skb_zerocopy(user_skb, skb, skb->len - cutlen, hlen);
526 	if (err)
527 		goto out;
528 
529 	/* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */
530 	pad_packet(dp, user_skb);
531 
532 	((struct nlmsghdr *) user_skb->data)->nlmsg_len = user_skb->len;
533 
534 	err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
535 	user_skb = NULL;
536 out:
537 	if (err)
538 		skb_tx_error(skb);
539 	kfree_skb(user_skb);
540 	kfree_skb(nskb);
541 	return err;
542 }
543 
544 static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
545 {
546 	struct ovs_header *ovs_header = info->userhdr;
547 	struct net *net = sock_net(skb->sk);
548 	struct nlattr **a = info->attrs;
549 	struct sw_flow_actions *acts;
550 	struct sk_buff *packet;
551 	struct sw_flow *flow;
552 	struct sw_flow_actions *sf_acts;
553 	struct datapath *dp;
554 	struct ethhdr *eth;
555 	struct vport *input_vport;
556 	u16 mru = 0;
557 	int len;
558 	int err;
559 	bool log = !a[OVS_PACKET_ATTR_PROBE];
560 
561 	err = -EINVAL;
562 	if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] ||
563 	    !a[OVS_PACKET_ATTR_ACTIONS])
564 		goto err;
565 
566 	len = nla_len(a[OVS_PACKET_ATTR_PACKET]);
567 	packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL);
568 	err = -ENOMEM;
569 	if (!packet)
570 		goto err;
571 	skb_reserve(packet, NET_IP_ALIGN);
572 
573 	nla_memcpy(__skb_put(packet, len), a[OVS_PACKET_ATTR_PACKET], len);
574 
575 	skb_reset_mac_header(packet);
576 	eth = eth_hdr(packet);
577 
578 	/* Normally, setting the skb 'protocol' field would be handled by a
579 	 * call to eth_type_trans(), but it assumes there's a sending
580 	 * device, which we may not have. */
581 	if (eth_proto_is_802_3(eth->h_proto))
582 		packet->protocol = eth->h_proto;
583 	else
584 		packet->protocol = htons(ETH_P_802_2);
585 
586 	/* Set packet's mru */
587 	if (a[OVS_PACKET_ATTR_MRU]) {
588 		mru = nla_get_u16(a[OVS_PACKET_ATTR_MRU]);
589 		packet->ignore_df = 1;
590 	}
591 	OVS_CB(packet)->mru = mru;
592 
593 	/* Build an sw_flow for sending this packet. */
594 	flow = ovs_flow_alloc();
595 	err = PTR_ERR(flow);
596 	if (IS_ERR(flow))
597 		goto err_kfree_skb;
598 
599 	err = ovs_flow_key_extract_userspace(net, a[OVS_PACKET_ATTR_KEY],
600 					     packet, &flow->key, log);
601 	if (err)
602 		goto err_flow_free;
603 
604 	err = ovs_nla_copy_actions(net, a[OVS_PACKET_ATTR_ACTIONS],
605 				   &flow->key, &acts, log);
606 	if (err)
607 		goto err_flow_free;
608 
609 	rcu_assign_pointer(flow->sf_acts, acts);
610 	packet->priority = flow->key.phy.priority;
611 	packet->mark = flow->key.phy.skb_mark;
612 
613 	rcu_read_lock();
614 	dp = get_dp_rcu(net, ovs_header->dp_ifindex);
615 	err = -ENODEV;
616 	if (!dp)
617 		goto err_unlock;
618 
619 	input_vport = ovs_vport_rcu(dp, flow->key.phy.in_port);
620 	if (!input_vport)
621 		input_vport = ovs_vport_rcu(dp, OVSP_LOCAL);
622 
623 	if (!input_vport)
624 		goto err_unlock;
625 
626 	packet->dev = input_vport->dev;
627 	OVS_CB(packet)->input_vport = input_vport;
628 	sf_acts = rcu_dereference(flow->sf_acts);
629 
630 	local_bh_disable();
631 	err = ovs_execute_actions(dp, packet, sf_acts, &flow->key);
632 	local_bh_enable();
633 	rcu_read_unlock();
634 
635 	ovs_flow_free(flow, false);
636 	return err;
637 
638 err_unlock:
639 	rcu_read_unlock();
640 err_flow_free:
641 	ovs_flow_free(flow, false);
642 err_kfree_skb:
643 	kfree_skb(packet);
644 err:
645 	return err;
646 }
647 
648 static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = {
649 	[OVS_PACKET_ATTR_PACKET] = { .len = ETH_HLEN },
650 	[OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED },
651 	[OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED },
652 	[OVS_PACKET_ATTR_PROBE] = { .type = NLA_FLAG },
653 	[OVS_PACKET_ATTR_MRU] = { .type = NLA_U16 },
654 };
655 
656 static const struct genl_ops dp_packet_genl_ops[] = {
657 	{ .cmd = OVS_PACKET_CMD_EXECUTE,
658 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
659 	  .policy = packet_policy,
660 	  .doit = ovs_packet_cmd_execute
661 	}
662 };
663 
664 static struct genl_family dp_packet_genl_family = {
665 	.id = GENL_ID_GENERATE,
666 	.hdrsize = sizeof(struct ovs_header),
667 	.name = OVS_PACKET_FAMILY,
668 	.version = OVS_PACKET_VERSION,
669 	.maxattr = OVS_PACKET_ATTR_MAX,
670 	.netnsok = true,
671 	.parallel_ops = true,
672 	.ops = dp_packet_genl_ops,
673 	.n_ops = ARRAY_SIZE(dp_packet_genl_ops),
674 };
675 
676 static void get_dp_stats(const struct datapath *dp, struct ovs_dp_stats *stats,
677 			 struct ovs_dp_megaflow_stats *mega_stats)
678 {
679 	int i;
680 
681 	memset(mega_stats, 0, sizeof(*mega_stats));
682 
683 	stats->n_flows = ovs_flow_tbl_count(&dp->table);
684 	mega_stats->n_masks = ovs_flow_tbl_num_masks(&dp->table);
685 
686 	stats->n_hit = stats->n_missed = stats->n_lost = 0;
687 
688 	for_each_possible_cpu(i) {
689 		const struct dp_stats_percpu *percpu_stats;
690 		struct dp_stats_percpu local_stats;
691 		unsigned int start;
692 
693 		percpu_stats = per_cpu_ptr(dp->stats_percpu, i);
694 
695 		do {
696 			start = u64_stats_fetch_begin_irq(&percpu_stats->syncp);
697 			local_stats = *percpu_stats;
698 		} while (u64_stats_fetch_retry_irq(&percpu_stats->syncp, start));
699 
700 		stats->n_hit += local_stats.n_hit;
701 		stats->n_missed += local_stats.n_missed;
702 		stats->n_lost += local_stats.n_lost;
703 		mega_stats->n_mask_hit += local_stats.n_mask_hit;
704 	}
705 }
706 
707 static bool should_fill_key(const struct sw_flow_id *sfid, uint32_t ufid_flags)
708 {
709 	return ovs_identifier_is_ufid(sfid) &&
710 	       !(ufid_flags & OVS_UFID_F_OMIT_KEY);
711 }
712 
713 static bool should_fill_mask(uint32_t ufid_flags)
714 {
715 	return !(ufid_flags & OVS_UFID_F_OMIT_MASK);
716 }
717 
718 static bool should_fill_actions(uint32_t ufid_flags)
719 {
720 	return !(ufid_flags & OVS_UFID_F_OMIT_ACTIONS);
721 }
722 
723 static size_t ovs_flow_cmd_msg_size(const struct sw_flow_actions *acts,
724 				    const struct sw_flow_id *sfid,
725 				    uint32_t ufid_flags)
726 {
727 	size_t len = NLMSG_ALIGN(sizeof(struct ovs_header));
728 
729 	/* OVS_FLOW_ATTR_UFID */
730 	if (sfid && ovs_identifier_is_ufid(sfid))
731 		len += nla_total_size(sfid->ufid_len);
732 
733 	/* OVS_FLOW_ATTR_KEY */
734 	if (!sfid || should_fill_key(sfid, ufid_flags))
735 		len += nla_total_size(ovs_key_attr_size());
736 
737 	/* OVS_FLOW_ATTR_MASK */
738 	if (should_fill_mask(ufid_flags))
739 		len += nla_total_size(ovs_key_attr_size());
740 
741 	/* OVS_FLOW_ATTR_ACTIONS */
742 	if (should_fill_actions(ufid_flags))
743 		len += nla_total_size(acts->orig_len);
744 
745 	return len
746 		+ nla_total_size_64bit(sizeof(struct ovs_flow_stats)) /* OVS_FLOW_ATTR_STATS */
747 		+ nla_total_size(1) /* OVS_FLOW_ATTR_TCP_FLAGS */
748 		+ nla_total_size_64bit(8); /* OVS_FLOW_ATTR_USED */
749 }
750 
751 /* Called with ovs_mutex or RCU read lock. */
752 static int ovs_flow_cmd_fill_stats(const struct sw_flow *flow,
753 				   struct sk_buff *skb)
754 {
755 	struct ovs_flow_stats stats;
756 	__be16 tcp_flags;
757 	unsigned long used;
758 
759 	ovs_flow_stats_get(flow, &stats, &used, &tcp_flags);
760 
761 	if (used &&
762 	    nla_put_u64_64bit(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used),
763 			      OVS_FLOW_ATTR_PAD))
764 		return -EMSGSIZE;
765 
766 	if (stats.n_packets &&
767 	    nla_put_64bit(skb, OVS_FLOW_ATTR_STATS,
768 			  sizeof(struct ovs_flow_stats), &stats,
769 			  OVS_FLOW_ATTR_PAD))
770 		return -EMSGSIZE;
771 
772 	if ((u8)ntohs(tcp_flags) &&
773 	     nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags)))
774 		return -EMSGSIZE;
775 
776 	return 0;
777 }
778 
779 /* Called with ovs_mutex or RCU read lock. */
780 static int ovs_flow_cmd_fill_actions(const struct sw_flow *flow,
781 				     struct sk_buff *skb, int skb_orig_len)
782 {
783 	struct nlattr *start;
784 	int err;
785 
786 	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
787 	 * this is the first flow to be dumped into 'skb'.  This is unusual for
788 	 * Netlink but individual action lists can be longer than
789 	 * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this.
790 	 * The userspace caller can always fetch the actions separately if it
791 	 * really wants them.  (Most userspace callers in fact don't care.)
792 	 *
793 	 * This can only fail for dump operations because the skb is always
794 	 * properly sized for single flows.
795 	 */
796 	start = nla_nest_start(skb, OVS_FLOW_ATTR_ACTIONS);
797 	if (start) {
798 		const struct sw_flow_actions *sf_acts;
799 
800 		sf_acts = rcu_dereference_ovsl(flow->sf_acts);
801 		err = ovs_nla_put_actions(sf_acts->actions,
802 					  sf_acts->actions_len, skb);
803 
804 		if (!err)
805 			nla_nest_end(skb, start);
806 		else {
807 			if (skb_orig_len)
808 				return err;
809 
810 			nla_nest_cancel(skb, start);
811 		}
812 	} else if (skb_orig_len) {
813 		return -EMSGSIZE;
814 	}
815 
816 	return 0;
817 }
818 
819 /* Called with ovs_mutex or RCU read lock. */
820 static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
821 				  struct sk_buff *skb, u32 portid,
822 				  u32 seq, u32 flags, u8 cmd, u32 ufid_flags)
823 {
824 	const int skb_orig_len = skb->len;
825 	struct ovs_header *ovs_header;
826 	int err;
827 
828 	ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family,
829 				 flags, cmd);
830 	if (!ovs_header)
831 		return -EMSGSIZE;
832 
833 	ovs_header->dp_ifindex = dp_ifindex;
834 
835 	err = ovs_nla_put_identifier(flow, skb);
836 	if (err)
837 		goto error;
838 
839 	if (should_fill_key(&flow->id, ufid_flags)) {
840 		err = ovs_nla_put_masked_key(flow, skb);
841 		if (err)
842 			goto error;
843 	}
844 
845 	if (should_fill_mask(ufid_flags)) {
846 		err = ovs_nla_put_mask(flow, skb);
847 		if (err)
848 			goto error;
849 	}
850 
851 	err = ovs_flow_cmd_fill_stats(flow, skb);
852 	if (err)
853 		goto error;
854 
855 	if (should_fill_actions(ufid_flags)) {
856 		err = ovs_flow_cmd_fill_actions(flow, skb, skb_orig_len);
857 		if (err)
858 			goto error;
859 	}
860 
861 	genlmsg_end(skb, ovs_header);
862 	return 0;
863 
864 error:
865 	genlmsg_cancel(skb, ovs_header);
866 	return err;
867 }
868 
869 /* May not be called with RCU read lock. */
870 static struct sk_buff *ovs_flow_cmd_alloc_info(const struct sw_flow_actions *acts,
871 					       const struct sw_flow_id *sfid,
872 					       struct genl_info *info,
873 					       bool always,
874 					       uint32_t ufid_flags)
875 {
876 	struct sk_buff *skb;
877 	size_t len;
878 
879 	if (!always && !ovs_must_notify(&dp_flow_genl_family, info, 0))
880 		return NULL;
881 
882 	len = ovs_flow_cmd_msg_size(acts, sfid, ufid_flags);
883 	skb = genlmsg_new(len, GFP_KERNEL);
884 	if (!skb)
885 		return ERR_PTR(-ENOMEM);
886 
887 	return skb;
888 }
889 
890 /* Called with ovs_mutex. */
891 static struct sk_buff *ovs_flow_cmd_build_info(const struct sw_flow *flow,
892 					       int dp_ifindex,
893 					       struct genl_info *info, u8 cmd,
894 					       bool always, u32 ufid_flags)
895 {
896 	struct sk_buff *skb;
897 	int retval;
898 
899 	skb = ovs_flow_cmd_alloc_info(ovsl_dereference(flow->sf_acts),
900 				      &flow->id, info, always, ufid_flags);
901 	if (IS_ERR_OR_NULL(skb))
902 		return skb;
903 
904 	retval = ovs_flow_cmd_fill_info(flow, dp_ifindex, skb,
905 					info->snd_portid, info->snd_seq, 0,
906 					cmd, ufid_flags);
907 	BUG_ON(retval < 0);
908 	return skb;
909 }
910 
911 static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
912 {
913 	struct net *net = sock_net(skb->sk);
914 	struct nlattr **a = info->attrs;
915 	struct ovs_header *ovs_header = info->userhdr;
916 	struct sw_flow *flow = NULL, *new_flow;
917 	struct sw_flow_mask mask;
918 	struct sk_buff *reply;
919 	struct datapath *dp;
920 	struct sw_flow_key key;
921 	struct sw_flow_actions *acts;
922 	struct sw_flow_match match;
923 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
924 	int error;
925 	bool log = !a[OVS_FLOW_ATTR_PROBE];
926 
927 	/* Must have key and actions. */
928 	error = -EINVAL;
929 	if (!a[OVS_FLOW_ATTR_KEY]) {
930 		OVS_NLERR(log, "Flow key attr not present in new flow.");
931 		goto error;
932 	}
933 	if (!a[OVS_FLOW_ATTR_ACTIONS]) {
934 		OVS_NLERR(log, "Flow actions attr not present in new flow.");
935 		goto error;
936 	}
937 
938 	/* Most of the time we need to allocate a new flow, do it before
939 	 * locking.
940 	 */
941 	new_flow = ovs_flow_alloc();
942 	if (IS_ERR(new_flow)) {
943 		error = PTR_ERR(new_flow);
944 		goto error;
945 	}
946 
947 	/* Extract key. */
948 	ovs_match_init(&match, &key, &mask);
949 	error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
950 				  a[OVS_FLOW_ATTR_MASK], log);
951 	if (error)
952 		goto err_kfree_flow;
953 
954 	ovs_flow_mask_key(&new_flow->key, &key, true, &mask);
955 
956 	/* Extract flow identifier. */
957 	error = ovs_nla_get_identifier(&new_flow->id, a[OVS_FLOW_ATTR_UFID],
958 				       &key, log);
959 	if (error)
960 		goto err_kfree_flow;
961 
962 	/* Validate actions. */
963 	error = ovs_nla_copy_actions(net, a[OVS_FLOW_ATTR_ACTIONS],
964 				     &new_flow->key, &acts, log);
965 	if (error) {
966 		OVS_NLERR(log, "Flow actions may not be safe on all matching packets.");
967 		goto err_kfree_flow;
968 	}
969 
970 	reply = ovs_flow_cmd_alloc_info(acts, &new_flow->id, info, false,
971 					ufid_flags);
972 	if (IS_ERR(reply)) {
973 		error = PTR_ERR(reply);
974 		goto err_kfree_acts;
975 	}
976 
977 	ovs_lock();
978 	dp = get_dp(net, ovs_header->dp_ifindex);
979 	if (unlikely(!dp)) {
980 		error = -ENODEV;
981 		goto err_unlock_ovs;
982 	}
983 
984 	/* Check if this is a duplicate flow */
985 	if (ovs_identifier_is_ufid(&new_flow->id))
986 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &new_flow->id);
987 	if (!flow)
988 		flow = ovs_flow_tbl_lookup(&dp->table, &key);
989 	if (likely(!flow)) {
990 		rcu_assign_pointer(new_flow->sf_acts, acts);
991 
992 		/* Put flow in bucket. */
993 		error = ovs_flow_tbl_insert(&dp->table, new_flow, &mask);
994 		if (unlikely(error)) {
995 			acts = NULL;
996 			goto err_unlock_ovs;
997 		}
998 
999 		if (unlikely(reply)) {
1000 			error = ovs_flow_cmd_fill_info(new_flow,
1001 						       ovs_header->dp_ifindex,
1002 						       reply, info->snd_portid,
1003 						       info->snd_seq, 0,
1004 						       OVS_FLOW_CMD_NEW,
1005 						       ufid_flags);
1006 			BUG_ON(error < 0);
1007 		}
1008 		ovs_unlock();
1009 	} else {
1010 		struct sw_flow_actions *old_acts;
1011 
1012 		/* Bail out if we're not allowed to modify an existing flow.
1013 		 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
1014 		 * because Generic Netlink treats the latter as a dump
1015 		 * request.  We also accept NLM_F_EXCL in case that bug ever
1016 		 * gets fixed.
1017 		 */
1018 		if (unlikely(info->nlhdr->nlmsg_flags & (NLM_F_CREATE
1019 							 | NLM_F_EXCL))) {
1020 			error = -EEXIST;
1021 			goto err_unlock_ovs;
1022 		}
1023 		/* The flow identifier has to be the same for flow updates.
1024 		 * Look for any overlapping flow.
1025 		 */
1026 		if (unlikely(!ovs_flow_cmp(flow, &match))) {
1027 			if (ovs_identifier_is_key(&flow->id))
1028 				flow = ovs_flow_tbl_lookup_exact(&dp->table,
1029 								 &match);
1030 			else /* UFID matches but key is different */
1031 				flow = NULL;
1032 			if (!flow) {
1033 				error = -ENOENT;
1034 				goto err_unlock_ovs;
1035 			}
1036 		}
1037 		/* Update actions. */
1038 		old_acts = ovsl_dereference(flow->sf_acts);
1039 		rcu_assign_pointer(flow->sf_acts, acts);
1040 
1041 		if (unlikely(reply)) {
1042 			error = ovs_flow_cmd_fill_info(flow,
1043 						       ovs_header->dp_ifindex,
1044 						       reply, info->snd_portid,
1045 						       info->snd_seq, 0,
1046 						       OVS_FLOW_CMD_NEW,
1047 						       ufid_flags);
1048 			BUG_ON(error < 0);
1049 		}
1050 		ovs_unlock();
1051 
1052 		ovs_nla_free_flow_actions_rcu(old_acts);
1053 		ovs_flow_free(new_flow, false);
1054 	}
1055 
1056 	if (reply)
1057 		ovs_notify(&dp_flow_genl_family, reply, info);
1058 	return 0;
1059 
1060 err_unlock_ovs:
1061 	ovs_unlock();
1062 	kfree_skb(reply);
1063 err_kfree_acts:
1064 	ovs_nla_free_flow_actions(acts);
1065 err_kfree_flow:
1066 	ovs_flow_free(new_flow, false);
1067 error:
1068 	return error;
1069 }
1070 
1071 /* Factor out action copy to avoid "Wframe-larger-than=1024" warning. */
1072 static struct sw_flow_actions *get_flow_actions(struct net *net,
1073 						const struct nlattr *a,
1074 						const struct sw_flow_key *key,
1075 						const struct sw_flow_mask *mask,
1076 						bool log)
1077 {
1078 	struct sw_flow_actions *acts;
1079 	struct sw_flow_key masked_key;
1080 	int error;
1081 
1082 	ovs_flow_mask_key(&masked_key, key, true, mask);
1083 	error = ovs_nla_copy_actions(net, a, &masked_key, &acts, log);
1084 	if (error) {
1085 		OVS_NLERR(log,
1086 			  "Actions may not be safe on all matching packets");
1087 		return ERR_PTR(error);
1088 	}
1089 
1090 	return acts;
1091 }
1092 
1093 static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
1094 {
1095 	struct net *net = sock_net(skb->sk);
1096 	struct nlattr **a = info->attrs;
1097 	struct ovs_header *ovs_header = info->userhdr;
1098 	struct sw_flow_key key;
1099 	struct sw_flow *flow;
1100 	struct sw_flow_mask mask;
1101 	struct sk_buff *reply = NULL;
1102 	struct datapath *dp;
1103 	struct sw_flow_actions *old_acts = NULL, *acts = NULL;
1104 	struct sw_flow_match match;
1105 	struct sw_flow_id sfid;
1106 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1107 	int error = 0;
1108 	bool log = !a[OVS_FLOW_ATTR_PROBE];
1109 	bool ufid_present;
1110 
1111 	ufid_present = ovs_nla_get_ufid(&sfid, a[OVS_FLOW_ATTR_UFID], log);
1112 	if (a[OVS_FLOW_ATTR_KEY]) {
1113 		ovs_match_init(&match, &key, &mask);
1114 		error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
1115 					  a[OVS_FLOW_ATTR_MASK], log);
1116 	} else if (!ufid_present) {
1117 		OVS_NLERR(log,
1118 			  "Flow set message rejected, Key attribute missing.");
1119 		error = -EINVAL;
1120 	}
1121 	if (error)
1122 		goto error;
1123 
1124 	/* Validate actions. */
1125 	if (a[OVS_FLOW_ATTR_ACTIONS]) {
1126 		if (!a[OVS_FLOW_ATTR_KEY]) {
1127 			OVS_NLERR(log,
1128 				  "Flow key attribute not present in set flow.");
1129 			error = -EINVAL;
1130 			goto error;
1131 		}
1132 
1133 		acts = get_flow_actions(net, a[OVS_FLOW_ATTR_ACTIONS], &key,
1134 					&mask, log);
1135 		if (IS_ERR(acts)) {
1136 			error = PTR_ERR(acts);
1137 			goto error;
1138 		}
1139 
1140 		/* Can allocate before locking if have acts. */
1141 		reply = ovs_flow_cmd_alloc_info(acts, &sfid, info, false,
1142 						ufid_flags);
1143 		if (IS_ERR(reply)) {
1144 			error = PTR_ERR(reply);
1145 			goto err_kfree_acts;
1146 		}
1147 	}
1148 
1149 	ovs_lock();
1150 	dp = get_dp(net, ovs_header->dp_ifindex);
1151 	if (unlikely(!dp)) {
1152 		error = -ENODEV;
1153 		goto err_unlock_ovs;
1154 	}
1155 	/* Check that the flow exists. */
1156 	if (ufid_present)
1157 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &sfid);
1158 	else
1159 		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1160 	if (unlikely(!flow)) {
1161 		error = -ENOENT;
1162 		goto err_unlock_ovs;
1163 	}
1164 
1165 	/* Update actions, if present. */
1166 	if (likely(acts)) {
1167 		old_acts = ovsl_dereference(flow->sf_acts);
1168 		rcu_assign_pointer(flow->sf_acts, acts);
1169 
1170 		if (unlikely(reply)) {
1171 			error = ovs_flow_cmd_fill_info(flow,
1172 						       ovs_header->dp_ifindex,
1173 						       reply, info->snd_portid,
1174 						       info->snd_seq, 0,
1175 						       OVS_FLOW_CMD_NEW,
1176 						       ufid_flags);
1177 			BUG_ON(error < 0);
1178 		}
1179 	} else {
1180 		/* Could not alloc without acts before locking. */
1181 		reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex,
1182 						info, OVS_FLOW_CMD_NEW, false,
1183 						ufid_flags);
1184 
1185 		if (IS_ERR(reply)) {
1186 			error = PTR_ERR(reply);
1187 			goto err_unlock_ovs;
1188 		}
1189 	}
1190 
1191 	/* Clear stats. */
1192 	if (a[OVS_FLOW_ATTR_CLEAR])
1193 		ovs_flow_stats_clear(flow);
1194 	ovs_unlock();
1195 
1196 	if (reply)
1197 		ovs_notify(&dp_flow_genl_family, reply, info);
1198 	if (old_acts)
1199 		ovs_nla_free_flow_actions_rcu(old_acts);
1200 
1201 	return 0;
1202 
1203 err_unlock_ovs:
1204 	ovs_unlock();
1205 	kfree_skb(reply);
1206 err_kfree_acts:
1207 	ovs_nla_free_flow_actions(acts);
1208 error:
1209 	return error;
1210 }
1211 
1212 static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
1213 {
1214 	struct nlattr **a = info->attrs;
1215 	struct ovs_header *ovs_header = info->userhdr;
1216 	struct net *net = sock_net(skb->sk);
1217 	struct sw_flow_key key;
1218 	struct sk_buff *reply;
1219 	struct sw_flow *flow;
1220 	struct datapath *dp;
1221 	struct sw_flow_match match;
1222 	struct sw_flow_id ufid;
1223 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1224 	int err = 0;
1225 	bool log = !a[OVS_FLOW_ATTR_PROBE];
1226 	bool ufid_present;
1227 
1228 	ufid_present = ovs_nla_get_ufid(&ufid, a[OVS_FLOW_ATTR_UFID], log);
1229 	if (a[OVS_FLOW_ATTR_KEY]) {
1230 		ovs_match_init(&match, &key, NULL);
1231 		err = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY], NULL,
1232 					log);
1233 	} else if (!ufid_present) {
1234 		OVS_NLERR(log,
1235 			  "Flow get message rejected, Key attribute missing.");
1236 		err = -EINVAL;
1237 	}
1238 	if (err)
1239 		return err;
1240 
1241 	ovs_lock();
1242 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1243 	if (!dp) {
1244 		err = -ENODEV;
1245 		goto unlock;
1246 	}
1247 
1248 	if (ufid_present)
1249 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &ufid);
1250 	else
1251 		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1252 	if (!flow) {
1253 		err = -ENOENT;
1254 		goto unlock;
1255 	}
1256 
1257 	reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex, info,
1258 					OVS_FLOW_CMD_NEW, true, ufid_flags);
1259 	if (IS_ERR(reply)) {
1260 		err = PTR_ERR(reply);
1261 		goto unlock;
1262 	}
1263 
1264 	ovs_unlock();
1265 	return genlmsg_reply(reply, info);
1266 unlock:
1267 	ovs_unlock();
1268 	return err;
1269 }
1270 
1271 static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
1272 {
1273 	struct nlattr **a = info->attrs;
1274 	struct ovs_header *ovs_header = info->userhdr;
1275 	struct net *net = sock_net(skb->sk);
1276 	struct sw_flow_key key;
1277 	struct sk_buff *reply;
1278 	struct sw_flow *flow = NULL;
1279 	struct datapath *dp;
1280 	struct sw_flow_match match;
1281 	struct sw_flow_id ufid;
1282 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1283 	int err;
1284 	bool log = !a[OVS_FLOW_ATTR_PROBE];
1285 	bool ufid_present;
1286 
1287 	ufid_present = ovs_nla_get_ufid(&ufid, a[OVS_FLOW_ATTR_UFID], log);
1288 	if (a[OVS_FLOW_ATTR_KEY]) {
1289 		ovs_match_init(&match, &key, NULL);
1290 		err = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
1291 					NULL, log);
1292 		if (unlikely(err))
1293 			return err;
1294 	}
1295 
1296 	ovs_lock();
1297 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1298 	if (unlikely(!dp)) {
1299 		err = -ENODEV;
1300 		goto unlock;
1301 	}
1302 
1303 	if (unlikely(!a[OVS_FLOW_ATTR_KEY] && !ufid_present)) {
1304 		err = ovs_flow_tbl_flush(&dp->table);
1305 		goto unlock;
1306 	}
1307 
1308 	if (ufid_present)
1309 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &ufid);
1310 	else
1311 		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1312 	if (unlikely(!flow)) {
1313 		err = -ENOENT;
1314 		goto unlock;
1315 	}
1316 
1317 	ovs_flow_tbl_remove(&dp->table, flow);
1318 	ovs_unlock();
1319 
1320 	reply = ovs_flow_cmd_alloc_info((const struct sw_flow_actions __force *) flow->sf_acts,
1321 					&flow->id, info, false, ufid_flags);
1322 	if (likely(reply)) {
1323 		if (likely(!IS_ERR(reply))) {
1324 			rcu_read_lock();	/*To keep RCU checker happy. */
1325 			err = ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex,
1326 						     reply, info->snd_portid,
1327 						     info->snd_seq, 0,
1328 						     OVS_FLOW_CMD_DEL,
1329 						     ufid_flags);
1330 			rcu_read_unlock();
1331 			BUG_ON(err < 0);
1332 
1333 			ovs_notify(&dp_flow_genl_family, reply, info);
1334 		} else {
1335 			netlink_set_err(sock_net(skb->sk)->genl_sock, 0, 0, PTR_ERR(reply));
1336 		}
1337 	}
1338 
1339 	ovs_flow_free(flow, true);
1340 	return 0;
1341 unlock:
1342 	ovs_unlock();
1343 	return err;
1344 }
1345 
1346 static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1347 {
1348 	struct nlattr *a[__OVS_FLOW_ATTR_MAX];
1349 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1350 	struct table_instance *ti;
1351 	struct datapath *dp;
1352 	u32 ufid_flags;
1353 	int err;
1354 
1355 	err = genlmsg_parse(cb->nlh, &dp_flow_genl_family, a,
1356 			    OVS_FLOW_ATTR_MAX, flow_policy);
1357 	if (err)
1358 		return err;
1359 	ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1360 
1361 	rcu_read_lock();
1362 	dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex);
1363 	if (!dp) {
1364 		rcu_read_unlock();
1365 		return -ENODEV;
1366 	}
1367 
1368 	ti = rcu_dereference(dp->table.ti);
1369 	for (;;) {
1370 		struct sw_flow *flow;
1371 		u32 bucket, obj;
1372 
1373 		bucket = cb->args[0];
1374 		obj = cb->args[1];
1375 		flow = ovs_flow_tbl_dump_next(ti, &bucket, &obj);
1376 		if (!flow)
1377 			break;
1378 
1379 		if (ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex, skb,
1380 					   NETLINK_CB(cb->skb).portid,
1381 					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
1382 					   OVS_FLOW_CMD_NEW, ufid_flags) < 0)
1383 			break;
1384 
1385 		cb->args[0] = bucket;
1386 		cb->args[1] = obj;
1387 	}
1388 	rcu_read_unlock();
1389 	return skb->len;
1390 }
1391 
1392 static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = {
1393 	[OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED },
1394 	[OVS_FLOW_ATTR_MASK] = { .type = NLA_NESTED },
1395 	[OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED },
1396 	[OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG },
1397 	[OVS_FLOW_ATTR_PROBE] = { .type = NLA_FLAG },
1398 	[OVS_FLOW_ATTR_UFID] = { .type = NLA_UNSPEC, .len = 1 },
1399 	[OVS_FLOW_ATTR_UFID_FLAGS] = { .type = NLA_U32 },
1400 };
1401 
1402 static const struct genl_ops dp_flow_genl_ops[] = {
1403 	{ .cmd = OVS_FLOW_CMD_NEW,
1404 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1405 	  .policy = flow_policy,
1406 	  .doit = ovs_flow_cmd_new
1407 	},
1408 	{ .cmd = OVS_FLOW_CMD_DEL,
1409 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1410 	  .policy = flow_policy,
1411 	  .doit = ovs_flow_cmd_del
1412 	},
1413 	{ .cmd = OVS_FLOW_CMD_GET,
1414 	  .flags = 0,		    /* OK for unprivileged users. */
1415 	  .policy = flow_policy,
1416 	  .doit = ovs_flow_cmd_get,
1417 	  .dumpit = ovs_flow_cmd_dump
1418 	},
1419 	{ .cmd = OVS_FLOW_CMD_SET,
1420 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1421 	  .policy = flow_policy,
1422 	  .doit = ovs_flow_cmd_set,
1423 	},
1424 };
1425 
1426 static struct genl_family dp_flow_genl_family = {
1427 	.id = GENL_ID_GENERATE,
1428 	.hdrsize = sizeof(struct ovs_header),
1429 	.name = OVS_FLOW_FAMILY,
1430 	.version = OVS_FLOW_VERSION,
1431 	.maxattr = OVS_FLOW_ATTR_MAX,
1432 	.netnsok = true,
1433 	.parallel_ops = true,
1434 	.ops = dp_flow_genl_ops,
1435 	.n_ops = ARRAY_SIZE(dp_flow_genl_ops),
1436 	.mcgrps = &ovs_dp_flow_multicast_group,
1437 	.n_mcgrps = 1,
1438 };
1439 
1440 static size_t ovs_dp_cmd_msg_size(void)
1441 {
1442 	size_t msgsize = NLMSG_ALIGN(sizeof(struct ovs_header));
1443 
1444 	msgsize += nla_total_size(IFNAMSIZ);
1445 	msgsize += nla_total_size_64bit(sizeof(struct ovs_dp_stats));
1446 	msgsize += nla_total_size_64bit(sizeof(struct ovs_dp_megaflow_stats));
1447 	msgsize += nla_total_size(sizeof(u32)); /* OVS_DP_ATTR_USER_FEATURES */
1448 
1449 	return msgsize;
1450 }
1451 
1452 /* Called with ovs_mutex. */
1453 static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
1454 				u32 portid, u32 seq, u32 flags, u8 cmd)
1455 {
1456 	struct ovs_header *ovs_header;
1457 	struct ovs_dp_stats dp_stats;
1458 	struct ovs_dp_megaflow_stats dp_megaflow_stats;
1459 	int err;
1460 
1461 	ovs_header = genlmsg_put(skb, portid, seq, &dp_datapath_genl_family,
1462 				   flags, cmd);
1463 	if (!ovs_header)
1464 		goto error;
1465 
1466 	ovs_header->dp_ifindex = get_dpifindex(dp);
1467 
1468 	err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp));
1469 	if (err)
1470 		goto nla_put_failure;
1471 
1472 	get_dp_stats(dp, &dp_stats, &dp_megaflow_stats);
1473 	if (nla_put_64bit(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats),
1474 			  &dp_stats, OVS_DP_ATTR_PAD))
1475 		goto nla_put_failure;
1476 
1477 	if (nla_put_64bit(skb, OVS_DP_ATTR_MEGAFLOW_STATS,
1478 			  sizeof(struct ovs_dp_megaflow_stats),
1479 			  &dp_megaflow_stats, OVS_DP_ATTR_PAD))
1480 		goto nla_put_failure;
1481 
1482 	if (nla_put_u32(skb, OVS_DP_ATTR_USER_FEATURES, dp->user_features))
1483 		goto nla_put_failure;
1484 
1485 	genlmsg_end(skb, ovs_header);
1486 	return 0;
1487 
1488 nla_put_failure:
1489 	genlmsg_cancel(skb, ovs_header);
1490 error:
1491 	return -EMSGSIZE;
1492 }
1493 
1494 static struct sk_buff *ovs_dp_cmd_alloc_info(void)
1495 {
1496 	return genlmsg_new(ovs_dp_cmd_msg_size(), GFP_KERNEL);
1497 }
1498 
1499 /* Called with rcu_read_lock or ovs_mutex. */
1500 static struct datapath *lookup_datapath(struct net *net,
1501 					const struct ovs_header *ovs_header,
1502 					struct nlattr *a[OVS_DP_ATTR_MAX + 1])
1503 {
1504 	struct datapath *dp;
1505 
1506 	if (!a[OVS_DP_ATTR_NAME])
1507 		dp = get_dp(net, ovs_header->dp_ifindex);
1508 	else {
1509 		struct vport *vport;
1510 
1511 		vport = ovs_vport_locate(net, nla_data(a[OVS_DP_ATTR_NAME]));
1512 		dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL;
1513 	}
1514 	return dp ? dp : ERR_PTR(-ENODEV);
1515 }
1516 
1517 static void ovs_dp_reset_user_features(struct sk_buff *skb, struct genl_info *info)
1518 {
1519 	struct datapath *dp;
1520 
1521 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1522 	if (IS_ERR(dp))
1523 		return;
1524 
1525 	WARN(dp->user_features, "Dropping previously announced user features\n");
1526 	dp->user_features = 0;
1527 }
1528 
1529 static void ovs_dp_change(struct datapath *dp, struct nlattr *a[])
1530 {
1531 	if (a[OVS_DP_ATTR_USER_FEATURES])
1532 		dp->user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
1533 }
1534 
1535 static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
1536 {
1537 	struct nlattr **a = info->attrs;
1538 	struct vport_parms parms;
1539 	struct sk_buff *reply;
1540 	struct datapath *dp;
1541 	struct vport *vport;
1542 	struct ovs_net *ovs_net;
1543 	int err, i;
1544 
1545 	err = -EINVAL;
1546 	if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
1547 		goto err;
1548 
1549 	reply = ovs_dp_cmd_alloc_info();
1550 	if (!reply)
1551 		return -ENOMEM;
1552 
1553 	err = -ENOMEM;
1554 	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
1555 	if (dp == NULL)
1556 		goto err_free_reply;
1557 
1558 	ovs_dp_set_net(dp, sock_net(skb->sk));
1559 
1560 	/* Allocate table. */
1561 	err = ovs_flow_tbl_init(&dp->table);
1562 	if (err)
1563 		goto err_free_dp;
1564 
1565 	dp->stats_percpu = netdev_alloc_pcpu_stats(struct dp_stats_percpu);
1566 	if (!dp->stats_percpu) {
1567 		err = -ENOMEM;
1568 		goto err_destroy_table;
1569 	}
1570 
1571 	dp->ports = kmalloc(DP_VPORT_HASH_BUCKETS * sizeof(struct hlist_head),
1572 			    GFP_KERNEL);
1573 	if (!dp->ports) {
1574 		err = -ENOMEM;
1575 		goto err_destroy_percpu;
1576 	}
1577 
1578 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
1579 		INIT_HLIST_HEAD(&dp->ports[i]);
1580 
1581 	/* Set up our datapath device. */
1582 	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
1583 	parms.type = OVS_VPORT_TYPE_INTERNAL;
1584 	parms.options = NULL;
1585 	parms.dp = dp;
1586 	parms.port_no = OVSP_LOCAL;
1587 	parms.upcall_portids = a[OVS_DP_ATTR_UPCALL_PID];
1588 
1589 	ovs_dp_change(dp, a);
1590 
1591 	/* So far only local changes have been made, now need the lock. */
1592 	ovs_lock();
1593 
1594 	vport = new_vport(&parms);
1595 	if (IS_ERR(vport)) {
1596 		err = PTR_ERR(vport);
1597 		if (err == -EBUSY)
1598 			err = -EEXIST;
1599 
1600 		if (err == -EEXIST) {
1601 			/* An outdated user space instance that does not understand
1602 			 * the concept of user_features has attempted to create a new
1603 			 * datapath and is likely to reuse it. Drop all user features.
1604 			 */
1605 			if (info->genlhdr->version < OVS_DP_VER_FEATURES)
1606 				ovs_dp_reset_user_features(skb, info);
1607 		}
1608 
1609 		goto err_destroy_ports_array;
1610 	}
1611 
1612 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1613 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1614 	BUG_ON(err < 0);
1615 
1616 	ovs_net = net_generic(ovs_dp_get_net(dp), ovs_net_id);
1617 	list_add_tail_rcu(&dp->list_node, &ovs_net->dps);
1618 
1619 	ovs_unlock();
1620 
1621 	ovs_notify(&dp_datapath_genl_family, reply, info);
1622 	return 0;
1623 
1624 err_destroy_ports_array:
1625 	ovs_unlock();
1626 	kfree(dp->ports);
1627 err_destroy_percpu:
1628 	free_percpu(dp->stats_percpu);
1629 err_destroy_table:
1630 	ovs_flow_tbl_destroy(&dp->table);
1631 err_free_dp:
1632 	kfree(dp);
1633 err_free_reply:
1634 	kfree_skb(reply);
1635 err:
1636 	return err;
1637 }
1638 
1639 /* Called with ovs_mutex. */
1640 static void __dp_destroy(struct datapath *dp)
1641 {
1642 	int i;
1643 
1644 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
1645 		struct vport *vport;
1646 		struct hlist_node *n;
1647 
1648 		hlist_for_each_entry_safe(vport, n, &dp->ports[i], dp_hash_node)
1649 			if (vport->port_no != OVSP_LOCAL)
1650 				ovs_dp_detach_port(vport);
1651 	}
1652 
1653 	list_del_rcu(&dp->list_node);
1654 
1655 	/* OVSP_LOCAL is datapath internal port. We need to make sure that
1656 	 * all ports in datapath are destroyed first before freeing datapath.
1657 	 */
1658 	ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
1659 
1660 	/* RCU destroy the flow table */
1661 	call_rcu(&dp->rcu, destroy_dp_rcu);
1662 }
1663 
1664 static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
1665 {
1666 	struct sk_buff *reply;
1667 	struct datapath *dp;
1668 	int err;
1669 
1670 	reply = ovs_dp_cmd_alloc_info();
1671 	if (!reply)
1672 		return -ENOMEM;
1673 
1674 	ovs_lock();
1675 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1676 	err = PTR_ERR(dp);
1677 	if (IS_ERR(dp))
1678 		goto err_unlock_free;
1679 
1680 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1681 				   info->snd_seq, 0, OVS_DP_CMD_DEL);
1682 	BUG_ON(err < 0);
1683 
1684 	__dp_destroy(dp);
1685 	ovs_unlock();
1686 
1687 	ovs_notify(&dp_datapath_genl_family, reply, info);
1688 
1689 	return 0;
1690 
1691 err_unlock_free:
1692 	ovs_unlock();
1693 	kfree_skb(reply);
1694 	return err;
1695 }
1696 
1697 static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
1698 {
1699 	struct sk_buff *reply;
1700 	struct datapath *dp;
1701 	int err;
1702 
1703 	reply = ovs_dp_cmd_alloc_info();
1704 	if (!reply)
1705 		return -ENOMEM;
1706 
1707 	ovs_lock();
1708 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1709 	err = PTR_ERR(dp);
1710 	if (IS_ERR(dp))
1711 		goto err_unlock_free;
1712 
1713 	ovs_dp_change(dp, info->attrs);
1714 
1715 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1716 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1717 	BUG_ON(err < 0);
1718 
1719 	ovs_unlock();
1720 	ovs_notify(&dp_datapath_genl_family, reply, info);
1721 
1722 	return 0;
1723 
1724 err_unlock_free:
1725 	ovs_unlock();
1726 	kfree_skb(reply);
1727 	return err;
1728 }
1729 
1730 static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
1731 {
1732 	struct sk_buff *reply;
1733 	struct datapath *dp;
1734 	int err;
1735 
1736 	reply = ovs_dp_cmd_alloc_info();
1737 	if (!reply)
1738 		return -ENOMEM;
1739 
1740 	ovs_lock();
1741 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1742 	if (IS_ERR(dp)) {
1743 		err = PTR_ERR(dp);
1744 		goto err_unlock_free;
1745 	}
1746 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1747 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1748 	BUG_ON(err < 0);
1749 	ovs_unlock();
1750 
1751 	return genlmsg_reply(reply, info);
1752 
1753 err_unlock_free:
1754 	ovs_unlock();
1755 	kfree_skb(reply);
1756 	return err;
1757 }
1758 
1759 static int ovs_dp_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1760 {
1761 	struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
1762 	struct datapath *dp;
1763 	int skip = cb->args[0];
1764 	int i = 0;
1765 
1766 	ovs_lock();
1767 	list_for_each_entry(dp, &ovs_net->dps, list_node) {
1768 		if (i >= skip &&
1769 		    ovs_dp_cmd_fill_info(dp, skb, NETLINK_CB(cb->skb).portid,
1770 					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1771 					 OVS_DP_CMD_NEW) < 0)
1772 			break;
1773 		i++;
1774 	}
1775 	ovs_unlock();
1776 
1777 	cb->args[0] = i;
1778 
1779 	return skb->len;
1780 }
1781 
1782 static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
1783 	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1784 	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1785 	[OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 },
1786 };
1787 
1788 static const struct genl_ops dp_datapath_genl_ops[] = {
1789 	{ .cmd = OVS_DP_CMD_NEW,
1790 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1791 	  .policy = datapath_policy,
1792 	  .doit = ovs_dp_cmd_new
1793 	},
1794 	{ .cmd = OVS_DP_CMD_DEL,
1795 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1796 	  .policy = datapath_policy,
1797 	  .doit = ovs_dp_cmd_del
1798 	},
1799 	{ .cmd = OVS_DP_CMD_GET,
1800 	  .flags = 0,		    /* OK for unprivileged users. */
1801 	  .policy = datapath_policy,
1802 	  .doit = ovs_dp_cmd_get,
1803 	  .dumpit = ovs_dp_cmd_dump
1804 	},
1805 	{ .cmd = OVS_DP_CMD_SET,
1806 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1807 	  .policy = datapath_policy,
1808 	  .doit = ovs_dp_cmd_set,
1809 	},
1810 };
1811 
1812 static struct genl_family dp_datapath_genl_family = {
1813 	.id = GENL_ID_GENERATE,
1814 	.hdrsize = sizeof(struct ovs_header),
1815 	.name = OVS_DATAPATH_FAMILY,
1816 	.version = OVS_DATAPATH_VERSION,
1817 	.maxattr = OVS_DP_ATTR_MAX,
1818 	.netnsok = true,
1819 	.parallel_ops = true,
1820 	.ops = dp_datapath_genl_ops,
1821 	.n_ops = ARRAY_SIZE(dp_datapath_genl_ops),
1822 	.mcgrps = &ovs_dp_datapath_multicast_group,
1823 	.n_mcgrps = 1,
1824 };
1825 
1826 /* Called with ovs_mutex or RCU read lock. */
1827 static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
1828 				   u32 portid, u32 seq, u32 flags, u8 cmd)
1829 {
1830 	struct ovs_header *ovs_header;
1831 	struct ovs_vport_stats vport_stats;
1832 	int err;
1833 
1834 	ovs_header = genlmsg_put(skb, portid, seq, &dp_vport_genl_family,
1835 				 flags, cmd);
1836 	if (!ovs_header)
1837 		return -EMSGSIZE;
1838 
1839 	ovs_header->dp_ifindex = get_dpifindex(vport->dp);
1840 
1841 	if (nla_put_u32(skb, OVS_VPORT_ATTR_PORT_NO, vport->port_no) ||
1842 	    nla_put_u32(skb, OVS_VPORT_ATTR_TYPE, vport->ops->type) ||
1843 	    nla_put_string(skb, OVS_VPORT_ATTR_NAME,
1844 			   ovs_vport_name(vport)))
1845 		goto nla_put_failure;
1846 
1847 	ovs_vport_get_stats(vport, &vport_stats);
1848 	if (nla_put_64bit(skb, OVS_VPORT_ATTR_STATS,
1849 			  sizeof(struct ovs_vport_stats), &vport_stats,
1850 			  OVS_VPORT_ATTR_PAD))
1851 		goto nla_put_failure;
1852 
1853 	if (ovs_vport_get_upcall_portids(vport, skb))
1854 		goto nla_put_failure;
1855 
1856 	err = ovs_vport_get_options(vport, skb);
1857 	if (err == -EMSGSIZE)
1858 		goto error;
1859 
1860 	genlmsg_end(skb, ovs_header);
1861 	return 0;
1862 
1863 nla_put_failure:
1864 	err = -EMSGSIZE;
1865 error:
1866 	genlmsg_cancel(skb, ovs_header);
1867 	return err;
1868 }
1869 
1870 static struct sk_buff *ovs_vport_cmd_alloc_info(void)
1871 {
1872 	return nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1873 }
1874 
1875 /* Called with ovs_mutex, only via ovs_dp_notify_wq(). */
1876 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, u32 portid,
1877 					 u32 seq, u8 cmd)
1878 {
1879 	struct sk_buff *skb;
1880 	int retval;
1881 
1882 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1883 	if (!skb)
1884 		return ERR_PTR(-ENOMEM);
1885 
1886 	retval = ovs_vport_cmd_fill_info(vport, skb, portid, seq, 0, cmd);
1887 	BUG_ON(retval < 0);
1888 
1889 	return skb;
1890 }
1891 
1892 /* Called with ovs_mutex or RCU read lock. */
1893 static struct vport *lookup_vport(struct net *net,
1894 				  const struct ovs_header *ovs_header,
1895 				  struct nlattr *a[OVS_VPORT_ATTR_MAX + 1])
1896 {
1897 	struct datapath *dp;
1898 	struct vport *vport;
1899 
1900 	if (a[OVS_VPORT_ATTR_NAME]) {
1901 		vport = ovs_vport_locate(net, nla_data(a[OVS_VPORT_ATTR_NAME]));
1902 		if (!vport)
1903 			return ERR_PTR(-ENODEV);
1904 		if (ovs_header->dp_ifindex &&
1905 		    ovs_header->dp_ifindex != get_dpifindex(vport->dp))
1906 			return ERR_PTR(-ENODEV);
1907 		return vport;
1908 	} else if (a[OVS_VPORT_ATTR_PORT_NO]) {
1909 		u32 port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
1910 
1911 		if (port_no >= DP_MAX_PORTS)
1912 			return ERR_PTR(-EFBIG);
1913 
1914 		dp = get_dp(net, ovs_header->dp_ifindex);
1915 		if (!dp)
1916 			return ERR_PTR(-ENODEV);
1917 
1918 		vport = ovs_vport_ovsl_rcu(dp, port_no);
1919 		if (!vport)
1920 			return ERR_PTR(-ENODEV);
1921 		return vport;
1922 	} else
1923 		return ERR_PTR(-EINVAL);
1924 }
1925 
1926 /* Called with ovs_mutex */
1927 static void update_headroom(struct datapath *dp)
1928 {
1929 	unsigned dev_headroom, max_headroom = 0;
1930 	struct net_device *dev;
1931 	struct vport *vport;
1932 	int i;
1933 
1934 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
1935 		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) {
1936 			dev = vport->dev;
1937 			dev_headroom = netdev_get_fwd_headroom(dev);
1938 			if (dev_headroom > max_headroom)
1939 				max_headroom = dev_headroom;
1940 		}
1941 	}
1942 
1943 	dp->max_headroom = max_headroom;
1944 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
1945 		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node)
1946 			netdev_set_rx_headroom(vport->dev, max_headroom);
1947 }
1948 
1949 static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
1950 {
1951 	struct nlattr **a = info->attrs;
1952 	struct ovs_header *ovs_header = info->userhdr;
1953 	struct vport_parms parms;
1954 	struct sk_buff *reply;
1955 	struct vport *vport;
1956 	struct datapath *dp;
1957 	u32 port_no;
1958 	int err;
1959 
1960 	if (!a[OVS_VPORT_ATTR_NAME] || !a[OVS_VPORT_ATTR_TYPE] ||
1961 	    !a[OVS_VPORT_ATTR_UPCALL_PID])
1962 		return -EINVAL;
1963 
1964 	port_no = a[OVS_VPORT_ATTR_PORT_NO]
1965 		? nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]) : 0;
1966 	if (port_no >= DP_MAX_PORTS)
1967 		return -EFBIG;
1968 
1969 	reply = ovs_vport_cmd_alloc_info();
1970 	if (!reply)
1971 		return -ENOMEM;
1972 
1973 	ovs_lock();
1974 restart:
1975 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1976 	err = -ENODEV;
1977 	if (!dp)
1978 		goto exit_unlock_free;
1979 
1980 	if (port_no) {
1981 		vport = ovs_vport_ovsl(dp, port_no);
1982 		err = -EBUSY;
1983 		if (vport)
1984 			goto exit_unlock_free;
1985 	} else {
1986 		for (port_no = 1; ; port_no++) {
1987 			if (port_no >= DP_MAX_PORTS) {
1988 				err = -EFBIG;
1989 				goto exit_unlock_free;
1990 			}
1991 			vport = ovs_vport_ovsl(dp, port_no);
1992 			if (!vport)
1993 				break;
1994 		}
1995 	}
1996 
1997 	parms.name = nla_data(a[OVS_VPORT_ATTR_NAME]);
1998 	parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
1999 	parms.options = a[OVS_VPORT_ATTR_OPTIONS];
2000 	parms.dp = dp;
2001 	parms.port_no = port_no;
2002 	parms.upcall_portids = a[OVS_VPORT_ATTR_UPCALL_PID];
2003 
2004 	vport = new_vport(&parms);
2005 	err = PTR_ERR(vport);
2006 	if (IS_ERR(vport)) {
2007 		if (err == -EAGAIN)
2008 			goto restart;
2009 		goto exit_unlock_free;
2010 	}
2011 
2012 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2013 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
2014 
2015 	if (netdev_get_fwd_headroom(vport->dev) > dp->max_headroom)
2016 		update_headroom(dp);
2017 	else
2018 		netdev_set_rx_headroom(vport->dev, dp->max_headroom);
2019 
2020 	BUG_ON(err < 0);
2021 	ovs_unlock();
2022 
2023 	ovs_notify(&dp_vport_genl_family, reply, info);
2024 	return 0;
2025 
2026 exit_unlock_free:
2027 	ovs_unlock();
2028 	kfree_skb(reply);
2029 	return err;
2030 }
2031 
2032 static int ovs_vport_cmd_set(struct sk_buff *skb, struct genl_info *info)
2033 {
2034 	struct nlattr **a = info->attrs;
2035 	struct sk_buff *reply;
2036 	struct vport *vport;
2037 	int err;
2038 
2039 	reply = ovs_vport_cmd_alloc_info();
2040 	if (!reply)
2041 		return -ENOMEM;
2042 
2043 	ovs_lock();
2044 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
2045 	err = PTR_ERR(vport);
2046 	if (IS_ERR(vport))
2047 		goto exit_unlock_free;
2048 
2049 	if (a[OVS_VPORT_ATTR_TYPE] &&
2050 	    nla_get_u32(a[OVS_VPORT_ATTR_TYPE]) != vport->ops->type) {
2051 		err = -EINVAL;
2052 		goto exit_unlock_free;
2053 	}
2054 
2055 	if (a[OVS_VPORT_ATTR_OPTIONS]) {
2056 		err = ovs_vport_set_options(vport, a[OVS_VPORT_ATTR_OPTIONS]);
2057 		if (err)
2058 			goto exit_unlock_free;
2059 	}
2060 
2061 
2062 	if (a[OVS_VPORT_ATTR_UPCALL_PID]) {
2063 		struct nlattr *ids = a[OVS_VPORT_ATTR_UPCALL_PID];
2064 
2065 		err = ovs_vport_set_upcall_portids(vport, ids);
2066 		if (err)
2067 			goto exit_unlock_free;
2068 	}
2069 
2070 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2071 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
2072 	BUG_ON(err < 0);
2073 
2074 	ovs_unlock();
2075 	ovs_notify(&dp_vport_genl_family, reply, info);
2076 	return 0;
2077 
2078 exit_unlock_free:
2079 	ovs_unlock();
2080 	kfree_skb(reply);
2081 	return err;
2082 }
2083 
2084 static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info)
2085 {
2086 	bool must_update_headroom = false;
2087 	struct nlattr **a = info->attrs;
2088 	struct sk_buff *reply;
2089 	struct datapath *dp;
2090 	struct vport *vport;
2091 	int err;
2092 
2093 	reply = ovs_vport_cmd_alloc_info();
2094 	if (!reply)
2095 		return -ENOMEM;
2096 
2097 	ovs_lock();
2098 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
2099 	err = PTR_ERR(vport);
2100 	if (IS_ERR(vport))
2101 		goto exit_unlock_free;
2102 
2103 	if (vport->port_no == OVSP_LOCAL) {
2104 		err = -EINVAL;
2105 		goto exit_unlock_free;
2106 	}
2107 
2108 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2109 				      info->snd_seq, 0, OVS_VPORT_CMD_DEL);
2110 	BUG_ON(err < 0);
2111 
2112 	/* the vport deletion may trigger dp headroom update */
2113 	dp = vport->dp;
2114 	if (netdev_get_fwd_headroom(vport->dev) == dp->max_headroom)
2115 		must_update_headroom = true;
2116 	netdev_reset_rx_headroom(vport->dev);
2117 	ovs_dp_detach_port(vport);
2118 
2119 	if (must_update_headroom)
2120 		update_headroom(dp);
2121 	ovs_unlock();
2122 
2123 	ovs_notify(&dp_vport_genl_family, reply, info);
2124 	return 0;
2125 
2126 exit_unlock_free:
2127 	ovs_unlock();
2128 	kfree_skb(reply);
2129 	return err;
2130 }
2131 
2132 static int ovs_vport_cmd_get(struct sk_buff *skb, struct genl_info *info)
2133 {
2134 	struct nlattr **a = info->attrs;
2135 	struct ovs_header *ovs_header = info->userhdr;
2136 	struct sk_buff *reply;
2137 	struct vport *vport;
2138 	int err;
2139 
2140 	reply = ovs_vport_cmd_alloc_info();
2141 	if (!reply)
2142 		return -ENOMEM;
2143 
2144 	rcu_read_lock();
2145 	vport = lookup_vport(sock_net(skb->sk), ovs_header, a);
2146 	err = PTR_ERR(vport);
2147 	if (IS_ERR(vport))
2148 		goto exit_unlock_free;
2149 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2150 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
2151 	BUG_ON(err < 0);
2152 	rcu_read_unlock();
2153 
2154 	return genlmsg_reply(reply, info);
2155 
2156 exit_unlock_free:
2157 	rcu_read_unlock();
2158 	kfree_skb(reply);
2159 	return err;
2160 }
2161 
2162 static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
2163 {
2164 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
2165 	struct datapath *dp;
2166 	int bucket = cb->args[0], skip = cb->args[1];
2167 	int i, j = 0;
2168 
2169 	rcu_read_lock();
2170 	dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex);
2171 	if (!dp) {
2172 		rcu_read_unlock();
2173 		return -ENODEV;
2174 	}
2175 	for (i = bucket; i < DP_VPORT_HASH_BUCKETS; i++) {
2176 		struct vport *vport;
2177 
2178 		j = 0;
2179 		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) {
2180 			if (j >= skip &&
2181 			    ovs_vport_cmd_fill_info(vport, skb,
2182 						    NETLINK_CB(cb->skb).portid,
2183 						    cb->nlh->nlmsg_seq,
2184 						    NLM_F_MULTI,
2185 						    OVS_VPORT_CMD_NEW) < 0)
2186 				goto out;
2187 
2188 			j++;
2189 		}
2190 		skip = 0;
2191 	}
2192 out:
2193 	rcu_read_unlock();
2194 
2195 	cb->args[0] = i;
2196 	cb->args[1] = j;
2197 
2198 	return skb->len;
2199 }
2200 
2201 static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
2202 	[OVS_VPORT_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
2203 	[OVS_VPORT_ATTR_STATS] = { .len = sizeof(struct ovs_vport_stats) },
2204 	[OVS_VPORT_ATTR_PORT_NO] = { .type = NLA_U32 },
2205 	[OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 },
2206 	[OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_U32 },
2207 	[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
2208 };
2209 
2210 static const struct genl_ops dp_vport_genl_ops[] = {
2211 	{ .cmd = OVS_VPORT_CMD_NEW,
2212 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2213 	  .policy = vport_policy,
2214 	  .doit = ovs_vport_cmd_new
2215 	},
2216 	{ .cmd = OVS_VPORT_CMD_DEL,
2217 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2218 	  .policy = vport_policy,
2219 	  .doit = ovs_vport_cmd_del
2220 	},
2221 	{ .cmd = OVS_VPORT_CMD_GET,
2222 	  .flags = 0,		    /* OK for unprivileged users. */
2223 	  .policy = vport_policy,
2224 	  .doit = ovs_vport_cmd_get,
2225 	  .dumpit = ovs_vport_cmd_dump
2226 	},
2227 	{ .cmd = OVS_VPORT_CMD_SET,
2228 	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2229 	  .policy = vport_policy,
2230 	  .doit = ovs_vport_cmd_set,
2231 	},
2232 };
2233 
2234 struct genl_family dp_vport_genl_family = {
2235 	.id = GENL_ID_GENERATE,
2236 	.hdrsize = sizeof(struct ovs_header),
2237 	.name = OVS_VPORT_FAMILY,
2238 	.version = OVS_VPORT_VERSION,
2239 	.maxattr = OVS_VPORT_ATTR_MAX,
2240 	.netnsok = true,
2241 	.parallel_ops = true,
2242 	.ops = dp_vport_genl_ops,
2243 	.n_ops = ARRAY_SIZE(dp_vport_genl_ops),
2244 	.mcgrps = &ovs_dp_vport_multicast_group,
2245 	.n_mcgrps = 1,
2246 };
2247 
2248 static struct genl_family * const dp_genl_families[] = {
2249 	&dp_datapath_genl_family,
2250 	&dp_vport_genl_family,
2251 	&dp_flow_genl_family,
2252 	&dp_packet_genl_family,
2253 };
2254 
2255 static void dp_unregister_genl(int n_families)
2256 {
2257 	int i;
2258 
2259 	for (i = 0; i < n_families; i++)
2260 		genl_unregister_family(dp_genl_families[i]);
2261 }
2262 
2263 static int dp_register_genl(void)
2264 {
2265 	int err;
2266 	int i;
2267 
2268 	for (i = 0; i < ARRAY_SIZE(dp_genl_families); i++) {
2269 
2270 		err = genl_register_family(dp_genl_families[i]);
2271 		if (err)
2272 			goto error;
2273 	}
2274 
2275 	return 0;
2276 
2277 error:
2278 	dp_unregister_genl(i);
2279 	return err;
2280 }
2281 
2282 static int __net_init ovs_init_net(struct net *net)
2283 {
2284 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2285 
2286 	INIT_LIST_HEAD(&ovs_net->dps);
2287 	INIT_WORK(&ovs_net->dp_notify_work, ovs_dp_notify_wq);
2288 	ovs_ct_init(net);
2289 	return 0;
2290 }
2291 
2292 static void __net_exit list_vports_from_net(struct net *net, struct net *dnet,
2293 					    struct list_head *head)
2294 {
2295 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2296 	struct datapath *dp;
2297 
2298 	list_for_each_entry(dp, &ovs_net->dps, list_node) {
2299 		int i;
2300 
2301 		for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
2302 			struct vport *vport;
2303 
2304 			hlist_for_each_entry(vport, &dp->ports[i], dp_hash_node) {
2305 				if (vport->ops->type != OVS_VPORT_TYPE_INTERNAL)
2306 					continue;
2307 
2308 				if (dev_net(vport->dev) == dnet)
2309 					list_add(&vport->detach_list, head);
2310 			}
2311 		}
2312 	}
2313 }
2314 
2315 static void __net_exit ovs_exit_net(struct net *dnet)
2316 {
2317 	struct datapath *dp, *dp_next;
2318 	struct ovs_net *ovs_net = net_generic(dnet, ovs_net_id);
2319 	struct vport *vport, *vport_next;
2320 	struct net *net;
2321 	LIST_HEAD(head);
2322 
2323 	ovs_ct_exit(dnet);
2324 	ovs_lock();
2325 	list_for_each_entry_safe(dp, dp_next, &ovs_net->dps, list_node)
2326 		__dp_destroy(dp);
2327 
2328 	rtnl_lock();
2329 	for_each_net(net)
2330 		list_vports_from_net(net, dnet, &head);
2331 	rtnl_unlock();
2332 
2333 	/* Detach all vports from given namespace. */
2334 	list_for_each_entry_safe(vport, vport_next, &head, detach_list) {
2335 		list_del(&vport->detach_list);
2336 		ovs_dp_detach_port(vport);
2337 	}
2338 
2339 	ovs_unlock();
2340 
2341 	cancel_work_sync(&ovs_net->dp_notify_work);
2342 }
2343 
2344 static struct pernet_operations ovs_net_ops = {
2345 	.init = ovs_init_net,
2346 	.exit = ovs_exit_net,
2347 	.id   = &ovs_net_id,
2348 	.size = sizeof(struct ovs_net),
2349 };
2350 
2351 static int __init dp_init(void)
2352 {
2353 	int err;
2354 
2355 	BUILD_BUG_ON(sizeof(struct ovs_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb));
2356 
2357 	pr_info("Open vSwitch switching datapath\n");
2358 
2359 	err = action_fifos_init();
2360 	if (err)
2361 		goto error;
2362 
2363 	err = ovs_internal_dev_rtnl_link_register();
2364 	if (err)
2365 		goto error_action_fifos_exit;
2366 
2367 	err = ovs_flow_init();
2368 	if (err)
2369 		goto error_unreg_rtnl_link;
2370 
2371 	err = ovs_vport_init();
2372 	if (err)
2373 		goto error_flow_exit;
2374 
2375 	err = register_pernet_device(&ovs_net_ops);
2376 	if (err)
2377 		goto error_vport_exit;
2378 
2379 	err = register_netdevice_notifier(&ovs_dp_device_notifier);
2380 	if (err)
2381 		goto error_netns_exit;
2382 
2383 	err = ovs_netdev_init();
2384 	if (err)
2385 		goto error_unreg_notifier;
2386 
2387 	err = dp_register_genl();
2388 	if (err < 0)
2389 		goto error_unreg_netdev;
2390 
2391 	return 0;
2392 
2393 error_unreg_netdev:
2394 	ovs_netdev_exit();
2395 error_unreg_notifier:
2396 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2397 error_netns_exit:
2398 	unregister_pernet_device(&ovs_net_ops);
2399 error_vport_exit:
2400 	ovs_vport_exit();
2401 error_flow_exit:
2402 	ovs_flow_exit();
2403 error_unreg_rtnl_link:
2404 	ovs_internal_dev_rtnl_link_unregister();
2405 error_action_fifos_exit:
2406 	action_fifos_exit();
2407 error:
2408 	return err;
2409 }
2410 
2411 static void dp_cleanup(void)
2412 {
2413 	dp_unregister_genl(ARRAY_SIZE(dp_genl_families));
2414 	ovs_netdev_exit();
2415 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2416 	unregister_pernet_device(&ovs_net_ops);
2417 	rcu_barrier();
2418 	ovs_vport_exit();
2419 	ovs_flow_exit();
2420 	ovs_internal_dev_rtnl_link_unregister();
2421 	action_fifos_exit();
2422 }
2423 
2424 module_init(dp_init);
2425 module_exit(dp_cleanup);
2426 
2427 MODULE_DESCRIPTION("Open vSwitch switching datapath");
2428 MODULE_LICENSE("GPL");
2429