xref: /linux/net/openvswitch/datapath.c (revision a8fe58cec351c25e09c393bf46117c0c47b5a17c)
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 static int queue_userspace_packet(struct datapath *dp, struct sk_buff *,
142 				  const struct sw_flow_key *,
143 				  const struct dp_upcall_info *);
144 
145 /* Must be called with rcu_read_lock. */
146 static struct datapath *get_dp_rcu(struct net *net, int dp_ifindex)
147 {
148 	struct net_device *dev = dev_get_by_index_rcu(net, dp_ifindex);
149 
150 	if (dev) {
151 		struct vport *vport = ovs_internal_dev_get_vport(dev);
152 		if (vport)
153 			return vport->dp;
154 	}
155 
156 	return NULL;
157 }
158 
159 /* The caller must hold either ovs_mutex or rcu_read_lock to keep the
160  * returned dp pointer valid.
161  */
162 static inline struct datapath *get_dp(struct net *net, int dp_ifindex)
163 {
164 	struct datapath *dp;
165 
166 	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held());
167 	rcu_read_lock();
168 	dp = get_dp_rcu(net, dp_ifindex);
169 	rcu_read_unlock();
170 
171 	return dp;
172 }
173 
174 /* Must be called with rcu_read_lock or ovs_mutex. */
175 const char *ovs_dp_name(const struct datapath *dp)
176 {
177 	struct vport *vport = ovs_vport_ovsl_rcu(dp, OVSP_LOCAL);
178 	return ovs_vport_name(vport);
179 }
180 
181 static int get_dpifindex(const struct datapath *dp)
182 {
183 	struct vport *local;
184 	int ifindex;
185 
186 	rcu_read_lock();
187 
188 	local = ovs_vport_rcu(dp, OVSP_LOCAL);
189 	if (local)
190 		ifindex = local->dev->ifindex;
191 	else
192 		ifindex = 0;
193 
194 	rcu_read_unlock();
195 
196 	return ifindex;
197 }
198 
199 static void destroy_dp_rcu(struct rcu_head *rcu)
200 {
201 	struct datapath *dp = container_of(rcu, struct datapath, rcu);
202 
203 	ovs_flow_tbl_destroy(&dp->table);
204 	free_percpu(dp->stats_percpu);
205 	kfree(dp->ports);
206 	kfree(dp);
207 }
208 
209 static struct hlist_head *vport_hash_bucket(const struct datapath *dp,
210 					    u16 port_no)
211 {
212 	return &dp->ports[port_no & (DP_VPORT_HASH_BUCKETS - 1)];
213 }
214 
215 /* Called with ovs_mutex or RCU read lock. */
216 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no)
217 {
218 	struct vport *vport;
219 	struct hlist_head *head;
220 
221 	head = vport_hash_bucket(dp, port_no);
222 	hlist_for_each_entry_rcu(vport, head, dp_hash_node) {
223 		if (vport->port_no == port_no)
224 			return vport;
225 	}
226 	return NULL;
227 }
228 
229 /* Called with ovs_mutex. */
230 static struct vport *new_vport(const struct vport_parms *parms)
231 {
232 	struct vport *vport;
233 
234 	vport = ovs_vport_add(parms);
235 	if (!IS_ERR(vport)) {
236 		struct datapath *dp = parms->dp;
237 		struct hlist_head *head = vport_hash_bucket(dp, vport->port_no);
238 
239 		hlist_add_head_rcu(&vport->dp_hash_node, head);
240 	}
241 	return vport;
242 }
243 
244 void ovs_dp_detach_port(struct vport *p)
245 {
246 	ASSERT_OVSL();
247 
248 	/* First drop references to device. */
249 	hlist_del_rcu(&p->dp_hash_node);
250 
251 	/* Then destroy it. */
252 	ovs_vport_del(p);
253 }
254 
255 /* Must be called with rcu_read_lock. */
256 void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key)
257 {
258 	const struct vport *p = OVS_CB(skb)->input_vport;
259 	struct datapath *dp = p->dp;
260 	struct sw_flow *flow;
261 	struct sw_flow_actions *sf_acts;
262 	struct dp_stats_percpu *stats;
263 	u64 *stats_counter;
264 	u32 n_mask_hit;
265 
266 	stats = this_cpu_ptr(dp->stats_percpu);
267 
268 	/* Look up flow. */
269 	flow = ovs_flow_tbl_lookup_stats(&dp->table, key, &n_mask_hit);
270 	if (unlikely(!flow)) {
271 		struct dp_upcall_info upcall;
272 		int error;
273 
274 		memset(&upcall, 0, sizeof(upcall));
275 		upcall.cmd = OVS_PACKET_CMD_MISS;
276 		upcall.portid = ovs_vport_find_upcall_portid(p, skb);
277 		upcall.mru = OVS_CB(skb)->mru;
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 	int err;
340 
341 	BUILD_BUG_ON(sizeof(*OVS_CB(skb)) > SKB_SGO_CB_OFFSET);
342 	segs = __skb_gso_segment(skb, NETIF_F_SG, false);
343 	if (IS_ERR(segs))
344 		return PTR_ERR(segs);
345 	if (segs == NULL)
346 		return -EINVAL;
347 
348 	if (gso_type & SKB_GSO_UDP) {
349 		/* The initial flow key extracted by ovs_flow_key_extract()
350 		 * in this case is for a first fragment, so we need to
351 		 * properly mark later fragments.
352 		 */
353 		later_key = *key;
354 		later_key.ip.frag = OVS_FRAG_TYPE_LATER;
355 	}
356 
357 	/* Queue all of the segments. */
358 	skb = segs;
359 	do {
360 		if (gso_type & SKB_GSO_UDP && skb != segs)
361 			key = &later_key;
362 
363 		err = queue_userspace_packet(dp, skb, key, upcall_info);
364 		if (err)
365 			break;
366 
367 	} while ((skb = skb->next));
368 
369 	/* Free all of the segments. */
370 	skb = segs;
371 	do {
372 		nskb = skb->next;
373 		if (err)
374 			kfree_skb(skb);
375 		else
376 			consume_skb(skb);
377 	} while ((skb = nskb));
378 	return err;
379 }
380 
381 static size_t upcall_msg_size(const struct dp_upcall_info *upcall_info,
382 			      unsigned int hdrlen)
383 {
384 	size_t size = NLMSG_ALIGN(sizeof(struct ovs_header))
385 		+ nla_total_size(hdrlen) /* OVS_PACKET_ATTR_PACKET */
386 		+ nla_total_size(ovs_key_attr_size()); /* OVS_PACKET_ATTR_KEY */
387 
388 	/* OVS_PACKET_ATTR_USERDATA */
389 	if (upcall_info->userdata)
390 		size += NLA_ALIGN(upcall_info->userdata->nla_len);
391 
392 	/* OVS_PACKET_ATTR_EGRESS_TUN_KEY */
393 	if (upcall_info->egress_tun_info)
394 		size += nla_total_size(ovs_tun_key_attr_size());
395 
396 	/* OVS_PACKET_ATTR_ACTIONS */
397 	if (upcall_info->actions_len)
398 		size += nla_total_size(upcall_info->actions_len);
399 
400 	/* OVS_PACKET_ATTR_MRU */
401 	if (upcall_info->mru)
402 		size += nla_total_size(sizeof(upcall_info->mru));
403 
404 	return size;
405 }
406 
407 static void pad_packet(struct datapath *dp, struct sk_buff *skb)
408 {
409 	if (!(dp->user_features & OVS_DP_F_UNALIGNED)) {
410 		size_t plen = NLA_ALIGN(skb->len) - skb->len;
411 
412 		if (plen > 0)
413 			memset(skb_put(skb, plen), 0, plen);
414 	}
415 }
416 
417 static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
418 				  const struct sw_flow_key *key,
419 				  const struct dp_upcall_info *upcall_info)
420 {
421 	struct ovs_header *upcall;
422 	struct sk_buff *nskb = NULL;
423 	struct sk_buff *user_skb = NULL; /* to be queued to userspace */
424 	struct nlattr *nla;
425 	struct genl_info info = {
426 		.dst_sk = ovs_dp_get_net(dp)->genl_sock,
427 		.snd_portid = upcall_info->portid,
428 	};
429 	size_t len;
430 	unsigned int hlen;
431 	int err, dp_ifindex;
432 
433 	dp_ifindex = get_dpifindex(dp);
434 	if (!dp_ifindex)
435 		return -ENODEV;
436 
437 	if (skb_vlan_tag_present(skb)) {
438 		nskb = skb_clone(skb, GFP_ATOMIC);
439 		if (!nskb)
440 			return -ENOMEM;
441 
442 		nskb = __vlan_hwaccel_push_inside(nskb);
443 		if (!nskb)
444 			return -ENOMEM;
445 
446 		skb = nskb;
447 	}
448 
449 	if (nla_attr_size(skb->len) > USHRT_MAX) {
450 		err = -EFBIG;
451 		goto out;
452 	}
453 
454 	/* Complete checksum if needed */
455 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
456 	    (err = skb_checksum_help(skb)))
457 		goto out;
458 
459 	/* Older versions of OVS user space enforce alignment of the last
460 	 * Netlink attribute to NLA_ALIGNTO which would require extensive
461 	 * padding logic. Only perform zerocopy if padding is not required.
462 	 */
463 	if (dp->user_features & OVS_DP_F_UNALIGNED)
464 		hlen = skb_zerocopy_headlen(skb);
465 	else
466 		hlen = skb->len;
467 
468 	len = upcall_msg_size(upcall_info, hlen);
469 	user_skb = genlmsg_new_unicast(len, &info, GFP_ATOMIC);
470 	if (!user_skb) {
471 		err = -ENOMEM;
472 		goto out;
473 	}
474 
475 	upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
476 			     0, upcall_info->cmd);
477 	upcall->dp_ifindex = dp_ifindex;
478 
479 	err = ovs_nla_put_key(key, key, OVS_PACKET_ATTR_KEY, false, user_skb);
480 	BUG_ON(err);
481 
482 	if (upcall_info->userdata)
483 		__nla_put(user_skb, OVS_PACKET_ATTR_USERDATA,
484 			  nla_len(upcall_info->userdata),
485 			  nla_data(upcall_info->userdata));
486 
487 	if (upcall_info->egress_tun_info) {
488 		nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_EGRESS_TUN_KEY);
489 		err = ovs_nla_put_tunnel_info(user_skb,
490 					      upcall_info->egress_tun_info);
491 		BUG_ON(err);
492 		nla_nest_end(user_skb, nla);
493 	}
494 
495 	if (upcall_info->actions_len) {
496 		nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_ACTIONS);
497 		err = ovs_nla_put_actions(upcall_info->actions,
498 					  upcall_info->actions_len,
499 					  user_skb);
500 		if (!err)
501 			nla_nest_end(user_skb, nla);
502 		else
503 			nla_nest_cancel(user_skb, nla);
504 	}
505 
506 	/* Add OVS_PACKET_ATTR_MRU */
507 	if (upcall_info->mru) {
508 		if (nla_put_u16(user_skb, OVS_PACKET_ATTR_MRU,
509 				upcall_info->mru)) {
510 			err = -ENOBUFS;
511 			goto out;
512 		}
513 		pad_packet(dp, user_skb);
514 	}
515 
516 	/* Only reserve room for attribute header, packet data is added
517 	 * in skb_zerocopy() */
518 	if (!(nla = nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, 0))) {
519 		err = -ENOBUFS;
520 		goto out;
521 	}
522 	nla->nla_len = nla_attr_size(skb->len);
523 
524 	err = skb_zerocopy(user_skb, skb, skb->len, hlen);
525 	if (err)
526 		goto out;
527 
528 	/* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */
529 	pad_packet(dp, user_skb);
530 
531 	((struct nlmsghdr *) user_skb->data)->nlmsg_len = user_skb->len;
532 
533 	err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
534 	user_skb = NULL;
535 out:
536 	if (err)
537 		skb_tx_error(skb);
538 	kfree_skb(user_skb);
539 	kfree_skb(nskb);
540 	return err;
541 }
542 
543 static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
544 {
545 	struct ovs_header *ovs_header = info->userhdr;
546 	struct net *net = sock_net(skb->sk);
547 	struct nlattr **a = info->attrs;
548 	struct sw_flow_actions *acts;
549 	struct sk_buff *packet;
550 	struct sw_flow *flow;
551 	struct sw_flow_actions *sf_acts;
552 	struct datapath *dp;
553 	struct ethhdr *eth;
554 	struct vport *input_vport;
555 	u16 mru = 0;
556 	int len;
557 	int err;
558 	bool log = !a[OVS_PACKET_ATTR_PROBE];
559 
560 	err = -EINVAL;
561 	if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] ||
562 	    !a[OVS_PACKET_ATTR_ACTIONS])
563 		goto err;
564 
565 	len = nla_len(a[OVS_PACKET_ATTR_PACKET]);
566 	packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL);
567 	err = -ENOMEM;
568 	if (!packet)
569 		goto err;
570 	skb_reserve(packet, NET_IP_ALIGN);
571 
572 	nla_memcpy(__skb_put(packet, len), a[OVS_PACKET_ATTR_PACKET], len);
573 
574 	skb_reset_mac_header(packet);
575 	eth = eth_hdr(packet);
576 
577 	/* Normally, setting the skb 'protocol' field would be handled by a
578 	 * call to eth_type_trans(), but it assumes there's a sending
579 	 * device, which we may not have. */
580 	if (eth_proto_is_802_3(eth->h_proto))
581 		packet->protocol = eth->h_proto;
582 	else
583 		packet->protocol = htons(ETH_P_802_2);
584 
585 	/* Set packet's mru */
586 	if (a[OVS_PACKET_ATTR_MRU]) {
587 		mru = nla_get_u16(a[OVS_PACKET_ATTR_MRU]);
588 		packet->ignore_df = 1;
589 	}
590 	OVS_CB(packet)->mru = mru;
591 
592 	/* Build an sw_flow for sending this packet. */
593 	flow = ovs_flow_alloc();
594 	err = PTR_ERR(flow);
595 	if (IS_ERR(flow))
596 		goto err_kfree_skb;
597 
598 	err = ovs_flow_key_extract_userspace(net, a[OVS_PACKET_ATTR_KEY],
599 					     packet, &flow->key, log);
600 	if (err)
601 		goto err_flow_free;
602 
603 	err = ovs_nla_copy_actions(net, a[OVS_PACKET_ATTR_ACTIONS],
604 				   &flow->key, &acts, log);
605 	if (err)
606 		goto err_flow_free;
607 
608 	rcu_assign_pointer(flow->sf_acts, acts);
609 	packet->priority = flow->key.phy.priority;
610 	packet->mark = flow->key.phy.skb_mark;
611 
612 	rcu_read_lock();
613 	dp = get_dp_rcu(net, ovs_header->dp_ifindex);
614 	err = -ENODEV;
615 	if (!dp)
616 		goto err_unlock;
617 
618 	input_vport = ovs_vport_rcu(dp, flow->key.phy.in_port);
619 	if (!input_vport)
620 		input_vport = ovs_vport_rcu(dp, OVSP_LOCAL);
621 
622 	if (!input_vport)
623 		goto err_unlock;
624 
625 	packet->dev = input_vport->dev;
626 	OVS_CB(packet)->input_vport = input_vport;
627 	sf_acts = rcu_dereference(flow->sf_acts);
628 
629 	local_bh_disable();
630 	err = ovs_execute_actions(dp, packet, sf_acts, &flow->key);
631 	local_bh_enable();
632 	rcu_read_unlock();
633 
634 	ovs_flow_free(flow, false);
635 	return err;
636 
637 err_unlock:
638 	rcu_read_unlock();
639 err_flow_free:
640 	ovs_flow_free(flow, false);
641 err_kfree_skb:
642 	kfree_skb(packet);
643 err:
644 	return err;
645 }
646 
647 static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = {
648 	[OVS_PACKET_ATTR_PACKET] = { .len = ETH_HLEN },
649 	[OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED },
650 	[OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED },
651 	[OVS_PACKET_ATTR_PROBE] = { .type = NLA_FLAG },
652 	[OVS_PACKET_ATTR_MRU] = { .type = NLA_U16 },
653 };
654 
655 static const struct genl_ops dp_packet_genl_ops[] = {
656 	{ .cmd = OVS_PACKET_CMD_EXECUTE,
657 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
658 	  .policy = packet_policy,
659 	  .doit = ovs_packet_cmd_execute
660 	}
661 };
662 
663 static struct genl_family dp_packet_genl_family = {
664 	.id = GENL_ID_GENERATE,
665 	.hdrsize = sizeof(struct ovs_header),
666 	.name = OVS_PACKET_FAMILY,
667 	.version = OVS_PACKET_VERSION,
668 	.maxattr = OVS_PACKET_ATTR_MAX,
669 	.netnsok = true,
670 	.parallel_ops = true,
671 	.ops = dp_packet_genl_ops,
672 	.n_ops = ARRAY_SIZE(dp_packet_genl_ops),
673 };
674 
675 static void get_dp_stats(const struct datapath *dp, struct ovs_dp_stats *stats,
676 			 struct ovs_dp_megaflow_stats *mega_stats)
677 {
678 	int i;
679 
680 	memset(mega_stats, 0, sizeof(*mega_stats));
681 
682 	stats->n_flows = ovs_flow_tbl_count(&dp->table);
683 	mega_stats->n_masks = ovs_flow_tbl_num_masks(&dp->table);
684 
685 	stats->n_hit = stats->n_missed = stats->n_lost = 0;
686 
687 	for_each_possible_cpu(i) {
688 		const struct dp_stats_percpu *percpu_stats;
689 		struct dp_stats_percpu local_stats;
690 		unsigned int start;
691 
692 		percpu_stats = per_cpu_ptr(dp->stats_percpu, i);
693 
694 		do {
695 			start = u64_stats_fetch_begin_irq(&percpu_stats->syncp);
696 			local_stats = *percpu_stats;
697 		} while (u64_stats_fetch_retry_irq(&percpu_stats->syncp, start));
698 
699 		stats->n_hit += local_stats.n_hit;
700 		stats->n_missed += local_stats.n_missed;
701 		stats->n_lost += local_stats.n_lost;
702 		mega_stats->n_mask_hit += local_stats.n_mask_hit;
703 	}
704 }
705 
706 static bool should_fill_key(const struct sw_flow_id *sfid, uint32_t ufid_flags)
707 {
708 	return ovs_identifier_is_ufid(sfid) &&
709 	       !(ufid_flags & OVS_UFID_F_OMIT_KEY);
710 }
711 
712 static bool should_fill_mask(uint32_t ufid_flags)
713 {
714 	return !(ufid_flags & OVS_UFID_F_OMIT_MASK);
715 }
716 
717 static bool should_fill_actions(uint32_t ufid_flags)
718 {
719 	return !(ufid_flags & OVS_UFID_F_OMIT_ACTIONS);
720 }
721 
722 static size_t ovs_flow_cmd_msg_size(const struct sw_flow_actions *acts,
723 				    const struct sw_flow_id *sfid,
724 				    uint32_t ufid_flags)
725 {
726 	size_t len = NLMSG_ALIGN(sizeof(struct ovs_header));
727 
728 	/* OVS_FLOW_ATTR_UFID */
729 	if (sfid && ovs_identifier_is_ufid(sfid))
730 		len += nla_total_size(sfid->ufid_len);
731 
732 	/* OVS_FLOW_ATTR_KEY */
733 	if (!sfid || should_fill_key(sfid, ufid_flags))
734 		len += nla_total_size(ovs_key_attr_size());
735 
736 	/* OVS_FLOW_ATTR_MASK */
737 	if (should_fill_mask(ufid_flags))
738 		len += nla_total_size(ovs_key_attr_size());
739 
740 	/* OVS_FLOW_ATTR_ACTIONS */
741 	if (should_fill_actions(ufid_flags))
742 		len += nla_total_size(acts->orig_len);
743 
744 	return len
745 		+ nla_total_size(sizeof(struct ovs_flow_stats)) /* OVS_FLOW_ATTR_STATS */
746 		+ nla_total_size(1) /* OVS_FLOW_ATTR_TCP_FLAGS */
747 		+ nla_total_size(8); /* OVS_FLOW_ATTR_USED */
748 }
749 
750 /* Called with ovs_mutex or RCU read lock. */
751 static int ovs_flow_cmd_fill_stats(const struct sw_flow *flow,
752 				   struct sk_buff *skb)
753 {
754 	struct ovs_flow_stats stats;
755 	__be16 tcp_flags;
756 	unsigned long used;
757 
758 	ovs_flow_stats_get(flow, &stats, &used, &tcp_flags);
759 
760 	if (used &&
761 	    nla_put_u64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used)))
762 		return -EMSGSIZE;
763 
764 	if (stats.n_packets &&
765 	    nla_put(skb, OVS_FLOW_ATTR_STATS, sizeof(struct ovs_flow_stats), &stats))
766 		return -EMSGSIZE;
767 
768 	if ((u8)ntohs(tcp_flags) &&
769 	     nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags)))
770 		return -EMSGSIZE;
771 
772 	return 0;
773 }
774 
775 /* Called with ovs_mutex or RCU read lock. */
776 static int ovs_flow_cmd_fill_actions(const struct sw_flow *flow,
777 				     struct sk_buff *skb, int skb_orig_len)
778 {
779 	struct nlattr *start;
780 	int err;
781 
782 	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
783 	 * this is the first flow to be dumped into 'skb'.  This is unusual for
784 	 * Netlink but individual action lists can be longer than
785 	 * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this.
786 	 * The userspace caller can always fetch the actions separately if it
787 	 * really wants them.  (Most userspace callers in fact don't care.)
788 	 *
789 	 * This can only fail for dump operations because the skb is always
790 	 * properly sized for single flows.
791 	 */
792 	start = nla_nest_start(skb, OVS_FLOW_ATTR_ACTIONS);
793 	if (start) {
794 		const struct sw_flow_actions *sf_acts;
795 
796 		sf_acts = rcu_dereference_ovsl(flow->sf_acts);
797 		err = ovs_nla_put_actions(sf_acts->actions,
798 					  sf_acts->actions_len, skb);
799 
800 		if (!err)
801 			nla_nest_end(skb, start);
802 		else {
803 			if (skb_orig_len)
804 				return err;
805 
806 			nla_nest_cancel(skb, start);
807 		}
808 	} else if (skb_orig_len) {
809 		return -EMSGSIZE;
810 	}
811 
812 	return 0;
813 }
814 
815 /* Called with ovs_mutex or RCU read lock. */
816 static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
817 				  struct sk_buff *skb, u32 portid,
818 				  u32 seq, u32 flags, u8 cmd, u32 ufid_flags)
819 {
820 	const int skb_orig_len = skb->len;
821 	struct ovs_header *ovs_header;
822 	int err;
823 
824 	ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family,
825 				 flags, cmd);
826 	if (!ovs_header)
827 		return -EMSGSIZE;
828 
829 	ovs_header->dp_ifindex = dp_ifindex;
830 
831 	err = ovs_nla_put_identifier(flow, skb);
832 	if (err)
833 		goto error;
834 
835 	if (should_fill_key(&flow->id, ufid_flags)) {
836 		err = ovs_nla_put_masked_key(flow, skb);
837 		if (err)
838 			goto error;
839 	}
840 
841 	if (should_fill_mask(ufid_flags)) {
842 		err = ovs_nla_put_mask(flow, skb);
843 		if (err)
844 			goto error;
845 	}
846 
847 	err = ovs_flow_cmd_fill_stats(flow, skb);
848 	if (err)
849 		goto error;
850 
851 	if (should_fill_actions(ufid_flags)) {
852 		err = ovs_flow_cmd_fill_actions(flow, skb, skb_orig_len);
853 		if (err)
854 			goto error;
855 	}
856 
857 	genlmsg_end(skb, ovs_header);
858 	return 0;
859 
860 error:
861 	genlmsg_cancel(skb, ovs_header);
862 	return err;
863 }
864 
865 /* May not be called with RCU read lock. */
866 static struct sk_buff *ovs_flow_cmd_alloc_info(const struct sw_flow_actions *acts,
867 					       const struct sw_flow_id *sfid,
868 					       struct genl_info *info,
869 					       bool always,
870 					       uint32_t ufid_flags)
871 {
872 	struct sk_buff *skb;
873 	size_t len;
874 
875 	if (!always && !ovs_must_notify(&dp_flow_genl_family, info, 0))
876 		return NULL;
877 
878 	len = ovs_flow_cmd_msg_size(acts, sfid, ufid_flags);
879 	skb = genlmsg_new_unicast(len, info, GFP_KERNEL);
880 	if (!skb)
881 		return ERR_PTR(-ENOMEM);
882 
883 	return skb;
884 }
885 
886 /* Called with ovs_mutex. */
887 static struct sk_buff *ovs_flow_cmd_build_info(const struct sw_flow *flow,
888 					       int dp_ifindex,
889 					       struct genl_info *info, u8 cmd,
890 					       bool always, u32 ufid_flags)
891 {
892 	struct sk_buff *skb;
893 	int retval;
894 
895 	skb = ovs_flow_cmd_alloc_info(ovsl_dereference(flow->sf_acts),
896 				      &flow->id, info, always, ufid_flags);
897 	if (IS_ERR_OR_NULL(skb))
898 		return skb;
899 
900 	retval = ovs_flow_cmd_fill_info(flow, dp_ifindex, skb,
901 					info->snd_portid, info->snd_seq, 0,
902 					cmd, ufid_flags);
903 	BUG_ON(retval < 0);
904 	return skb;
905 }
906 
907 static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
908 {
909 	struct net *net = sock_net(skb->sk);
910 	struct nlattr **a = info->attrs;
911 	struct ovs_header *ovs_header = info->userhdr;
912 	struct sw_flow *flow = NULL, *new_flow;
913 	struct sw_flow_mask mask;
914 	struct sk_buff *reply;
915 	struct datapath *dp;
916 	struct sw_flow_key key;
917 	struct sw_flow_actions *acts;
918 	struct sw_flow_match match;
919 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
920 	int error;
921 	bool log = !a[OVS_FLOW_ATTR_PROBE];
922 
923 	/* Must have key and actions. */
924 	error = -EINVAL;
925 	if (!a[OVS_FLOW_ATTR_KEY]) {
926 		OVS_NLERR(log, "Flow key attr not present in new flow.");
927 		goto error;
928 	}
929 	if (!a[OVS_FLOW_ATTR_ACTIONS]) {
930 		OVS_NLERR(log, "Flow actions attr not present in new flow.");
931 		goto error;
932 	}
933 
934 	/* Most of the time we need to allocate a new flow, do it before
935 	 * locking.
936 	 */
937 	new_flow = ovs_flow_alloc();
938 	if (IS_ERR(new_flow)) {
939 		error = PTR_ERR(new_flow);
940 		goto error;
941 	}
942 
943 	/* Extract key. */
944 	ovs_match_init(&match, &key, &mask);
945 	error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
946 				  a[OVS_FLOW_ATTR_MASK], log);
947 	if (error)
948 		goto err_kfree_flow;
949 
950 	ovs_flow_mask_key(&new_flow->key, &key, true, &mask);
951 
952 	/* Extract flow identifier. */
953 	error = ovs_nla_get_identifier(&new_flow->id, a[OVS_FLOW_ATTR_UFID],
954 				       &key, log);
955 	if (error)
956 		goto err_kfree_flow;
957 
958 	/* Validate actions. */
959 	error = ovs_nla_copy_actions(net, a[OVS_FLOW_ATTR_ACTIONS],
960 				     &new_flow->key, &acts, log);
961 	if (error) {
962 		OVS_NLERR(log, "Flow actions may not be safe on all matching packets.");
963 		goto err_kfree_flow;
964 	}
965 
966 	reply = ovs_flow_cmd_alloc_info(acts, &new_flow->id, info, false,
967 					ufid_flags);
968 	if (IS_ERR(reply)) {
969 		error = PTR_ERR(reply);
970 		goto err_kfree_acts;
971 	}
972 
973 	ovs_lock();
974 	dp = get_dp(net, ovs_header->dp_ifindex);
975 	if (unlikely(!dp)) {
976 		error = -ENODEV;
977 		goto err_unlock_ovs;
978 	}
979 
980 	/* Check if this is a duplicate flow */
981 	if (ovs_identifier_is_ufid(&new_flow->id))
982 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &new_flow->id);
983 	if (!flow)
984 		flow = ovs_flow_tbl_lookup(&dp->table, &key);
985 	if (likely(!flow)) {
986 		rcu_assign_pointer(new_flow->sf_acts, acts);
987 
988 		/* Put flow in bucket. */
989 		error = ovs_flow_tbl_insert(&dp->table, new_flow, &mask);
990 		if (unlikely(error)) {
991 			acts = NULL;
992 			goto err_unlock_ovs;
993 		}
994 
995 		if (unlikely(reply)) {
996 			error = ovs_flow_cmd_fill_info(new_flow,
997 						       ovs_header->dp_ifindex,
998 						       reply, info->snd_portid,
999 						       info->snd_seq, 0,
1000 						       OVS_FLOW_CMD_NEW,
1001 						       ufid_flags);
1002 			BUG_ON(error < 0);
1003 		}
1004 		ovs_unlock();
1005 	} else {
1006 		struct sw_flow_actions *old_acts;
1007 
1008 		/* Bail out if we're not allowed to modify an existing flow.
1009 		 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
1010 		 * because Generic Netlink treats the latter as a dump
1011 		 * request.  We also accept NLM_F_EXCL in case that bug ever
1012 		 * gets fixed.
1013 		 */
1014 		if (unlikely(info->nlhdr->nlmsg_flags & (NLM_F_CREATE
1015 							 | NLM_F_EXCL))) {
1016 			error = -EEXIST;
1017 			goto err_unlock_ovs;
1018 		}
1019 		/* The flow identifier has to be the same for flow updates.
1020 		 * Look for any overlapping flow.
1021 		 */
1022 		if (unlikely(!ovs_flow_cmp(flow, &match))) {
1023 			if (ovs_identifier_is_key(&flow->id))
1024 				flow = ovs_flow_tbl_lookup_exact(&dp->table,
1025 								 &match);
1026 			else /* UFID matches but key is different */
1027 				flow = NULL;
1028 			if (!flow) {
1029 				error = -ENOENT;
1030 				goto err_unlock_ovs;
1031 			}
1032 		}
1033 		/* Update actions. */
1034 		old_acts = ovsl_dereference(flow->sf_acts);
1035 		rcu_assign_pointer(flow->sf_acts, acts);
1036 
1037 		if (unlikely(reply)) {
1038 			error = ovs_flow_cmd_fill_info(flow,
1039 						       ovs_header->dp_ifindex,
1040 						       reply, info->snd_portid,
1041 						       info->snd_seq, 0,
1042 						       OVS_FLOW_CMD_NEW,
1043 						       ufid_flags);
1044 			BUG_ON(error < 0);
1045 		}
1046 		ovs_unlock();
1047 
1048 		ovs_nla_free_flow_actions_rcu(old_acts);
1049 		ovs_flow_free(new_flow, false);
1050 	}
1051 
1052 	if (reply)
1053 		ovs_notify(&dp_flow_genl_family, reply, info);
1054 	return 0;
1055 
1056 err_unlock_ovs:
1057 	ovs_unlock();
1058 	kfree_skb(reply);
1059 err_kfree_acts:
1060 	ovs_nla_free_flow_actions(acts);
1061 err_kfree_flow:
1062 	ovs_flow_free(new_flow, false);
1063 error:
1064 	return error;
1065 }
1066 
1067 /* Factor out action copy to avoid "Wframe-larger-than=1024" warning. */
1068 static struct sw_flow_actions *get_flow_actions(struct net *net,
1069 						const struct nlattr *a,
1070 						const struct sw_flow_key *key,
1071 						const struct sw_flow_mask *mask,
1072 						bool log)
1073 {
1074 	struct sw_flow_actions *acts;
1075 	struct sw_flow_key masked_key;
1076 	int error;
1077 
1078 	ovs_flow_mask_key(&masked_key, key, true, mask);
1079 	error = ovs_nla_copy_actions(net, a, &masked_key, &acts, log);
1080 	if (error) {
1081 		OVS_NLERR(log,
1082 			  "Actions may not be safe on all matching packets");
1083 		return ERR_PTR(error);
1084 	}
1085 
1086 	return acts;
1087 }
1088 
1089 static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
1090 {
1091 	struct net *net = sock_net(skb->sk);
1092 	struct nlattr **a = info->attrs;
1093 	struct ovs_header *ovs_header = info->userhdr;
1094 	struct sw_flow_key key;
1095 	struct sw_flow *flow;
1096 	struct sw_flow_mask mask;
1097 	struct sk_buff *reply = NULL;
1098 	struct datapath *dp;
1099 	struct sw_flow_actions *old_acts = NULL, *acts = NULL;
1100 	struct sw_flow_match match;
1101 	struct sw_flow_id sfid;
1102 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1103 	int error;
1104 	bool log = !a[OVS_FLOW_ATTR_PROBE];
1105 	bool ufid_present;
1106 
1107 	/* Extract key. */
1108 	error = -EINVAL;
1109 	if (!a[OVS_FLOW_ATTR_KEY]) {
1110 		OVS_NLERR(log, "Flow key attribute not present in set flow.");
1111 		goto error;
1112 	}
1113 
1114 	ufid_present = ovs_nla_get_ufid(&sfid, a[OVS_FLOW_ATTR_UFID], log);
1115 	ovs_match_init(&match, &key, &mask);
1116 	error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
1117 				  a[OVS_FLOW_ATTR_MASK], log);
1118 	if (error)
1119 		goto error;
1120 
1121 	/* Validate actions. */
1122 	if (a[OVS_FLOW_ATTR_ACTIONS]) {
1123 		acts = get_flow_actions(net, a[OVS_FLOW_ATTR_ACTIONS], &key,
1124 					&mask, log);
1125 		if (IS_ERR(acts)) {
1126 			error = PTR_ERR(acts);
1127 			goto error;
1128 		}
1129 
1130 		/* Can allocate before locking if have acts. */
1131 		reply = ovs_flow_cmd_alloc_info(acts, &sfid, info, false,
1132 						ufid_flags);
1133 		if (IS_ERR(reply)) {
1134 			error = PTR_ERR(reply);
1135 			goto err_kfree_acts;
1136 		}
1137 	}
1138 
1139 	ovs_lock();
1140 	dp = get_dp(net, ovs_header->dp_ifindex);
1141 	if (unlikely(!dp)) {
1142 		error = -ENODEV;
1143 		goto err_unlock_ovs;
1144 	}
1145 	/* Check that the flow exists. */
1146 	if (ufid_present)
1147 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &sfid);
1148 	else
1149 		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1150 	if (unlikely(!flow)) {
1151 		error = -ENOENT;
1152 		goto err_unlock_ovs;
1153 	}
1154 
1155 	/* Update actions, if present. */
1156 	if (likely(acts)) {
1157 		old_acts = ovsl_dereference(flow->sf_acts);
1158 		rcu_assign_pointer(flow->sf_acts, acts);
1159 
1160 		if (unlikely(reply)) {
1161 			error = ovs_flow_cmd_fill_info(flow,
1162 						       ovs_header->dp_ifindex,
1163 						       reply, info->snd_portid,
1164 						       info->snd_seq, 0,
1165 						       OVS_FLOW_CMD_NEW,
1166 						       ufid_flags);
1167 			BUG_ON(error < 0);
1168 		}
1169 	} else {
1170 		/* Could not alloc without acts before locking. */
1171 		reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex,
1172 						info, OVS_FLOW_CMD_NEW, false,
1173 						ufid_flags);
1174 
1175 		if (IS_ERR(reply)) {
1176 			error = PTR_ERR(reply);
1177 			goto err_unlock_ovs;
1178 		}
1179 	}
1180 
1181 	/* Clear stats. */
1182 	if (a[OVS_FLOW_ATTR_CLEAR])
1183 		ovs_flow_stats_clear(flow);
1184 	ovs_unlock();
1185 
1186 	if (reply)
1187 		ovs_notify(&dp_flow_genl_family, reply, info);
1188 	if (old_acts)
1189 		ovs_nla_free_flow_actions_rcu(old_acts);
1190 
1191 	return 0;
1192 
1193 err_unlock_ovs:
1194 	ovs_unlock();
1195 	kfree_skb(reply);
1196 err_kfree_acts:
1197 	ovs_nla_free_flow_actions(acts);
1198 error:
1199 	return error;
1200 }
1201 
1202 static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
1203 {
1204 	struct nlattr **a = info->attrs;
1205 	struct ovs_header *ovs_header = info->userhdr;
1206 	struct net *net = sock_net(skb->sk);
1207 	struct sw_flow_key key;
1208 	struct sk_buff *reply;
1209 	struct sw_flow *flow;
1210 	struct datapath *dp;
1211 	struct sw_flow_match match;
1212 	struct sw_flow_id ufid;
1213 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1214 	int err = 0;
1215 	bool log = !a[OVS_FLOW_ATTR_PROBE];
1216 	bool ufid_present;
1217 
1218 	ufid_present = ovs_nla_get_ufid(&ufid, a[OVS_FLOW_ATTR_UFID], log);
1219 	if (a[OVS_FLOW_ATTR_KEY]) {
1220 		ovs_match_init(&match, &key, NULL);
1221 		err = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY], NULL,
1222 					log);
1223 	} else if (!ufid_present) {
1224 		OVS_NLERR(log,
1225 			  "Flow get message rejected, Key attribute missing.");
1226 		err = -EINVAL;
1227 	}
1228 	if (err)
1229 		return err;
1230 
1231 	ovs_lock();
1232 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1233 	if (!dp) {
1234 		err = -ENODEV;
1235 		goto unlock;
1236 	}
1237 
1238 	if (ufid_present)
1239 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &ufid);
1240 	else
1241 		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1242 	if (!flow) {
1243 		err = -ENOENT;
1244 		goto unlock;
1245 	}
1246 
1247 	reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex, info,
1248 					OVS_FLOW_CMD_NEW, true, ufid_flags);
1249 	if (IS_ERR(reply)) {
1250 		err = PTR_ERR(reply);
1251 		goto unlock;
1252 	}
1253 
1254 	ovs_unlock();
1255 	return genlmsg_reply(reply, info);
1256 unlock:
1257 	ovs_unlock();
1258 	return err;
1259 }
1260 
1261 static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
1262 {
1263 	struct nlattr **a = info->attrs;
1264 	struct ovs_header *ovs_header = info->userhdr;
1265 	struct net *net = sock_net(skb->sk);
1266 	struct sw_flow_key key;
1267 	struct sk_buff *reply;
1268 	struct sw_flow *flow = NULL;
1269 	struct datapath *dp;
1270 	struct sw_flow_match match;
1271 	struct sw_flow_id ufid;
1272 	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1273 	int err;
1274 	bool log = !a[OVS_FLOW_ATTR_PROBE];
1275 	bool ufid_present;
1276 
1277 	ufid_present = ovs_nla_get_ufid(&ufid, a[OVS_FLOW_ATTR_UFID], log);
1278 	if (a[OVS_FLOW_ATTR_KEY]) {
1279 		ovs_match_init(&match, &key, NULL);
1280 		err = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
1281 					NULL, log);
1282 		if (unlikely(err))
1283 			return err;
1284 	}
1285 
1286 	ovs_lock();
1287 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1288 	if (unlikely(!dp)) {
1289 		err = -ENODEV;
1290 		goto unlock;
1291 	}
1292 
1293 	if (unlikely(!a[OVS_FLOW_ATTR_KEY] && !ufid_present)) {
1294 		err = ovs_flow_tbl_flush(&dp->table);
1295 		goto unlock;
1296 	}
1297 
1298 	if (ufid_present)
1299 		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &ufid);
1300 	else
1301 		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
1302 	if (unlikely(!flow)) {
1303 		err = -ENOENT;
1304 		goto unlock;
1305 	}
1306 
1307 	ovs_flow_tbl_remove(&dp->table, flow);
1308 	ovs_unlock();
1309 
1310 	reply = ovs_flow_cmd_alloc_info((const struct sw_flow_actions __force *) flow->sf_acts,
1311 					&flow->id, info, false, ufid_flags);
1312 	if (likely(reply)) {
1313 		if (likely(!IS_ERR(reply))) {
1314 			rcu_read_lock();	/*To keep RCU checker happy. */
1315 			err = ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex,
1316 						     reply, info->snd_portid,
1317 						     info->snd_seq, 0,
1318 						     OVS_FLOW_CMD_DEL,
1319 						     ufid_flags);
1320 			rcu_read_unlock();
1321 			BUG_ON(err < 0);
1322 
1323 			ovs_notify(&dp_flow_genl_family, reply, info);
1324 		} else {
1325 			netlink_set_err(sock_net(skb->sk)->genl_sock, 0, 0, PTR_ERR(reply));
1326 		}
1327 	}
1328 
1329 	ovs_flow_free(flow, true);
1330 	return 0;
1331 unlock:
1332 	ovs_unlock();
1333 	return err;
1334 }
1335 
1336 static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1337 {
1338 	struct nlattr *a[__OVS_FLOW_ATTR_MAX];
1339 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
1340 	struct table_instance *ti;
1341 	struct datapath *dp;
1342 	u32 ufid_flags;
1343 	int err;
1344 
1345 	err = genlmsg_parse(cb->nlh, &dp_flow_genl_family, a,
1346 			    OVS_FLOW_ATTR_MAX, flow_policy);
1347 	if (err)
1348 		return err;
1349 	ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
1350 
1351 	rcu_read_lock();
1352 	dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex);
1353 	if (!dp) {
1354 		rcu_read_unlock();
1355 		return -ENODEV;
1356 	}
1357 
1358 	ti = rcu_dereference(dp->table.ti);
1359 	for (;;) {
1360 		struct sw_flow *flow;
1361 		u32 bucket, obj;
1362 
1363 		bucket = cb->args[0];
1364 		obj = cb->args[1];
1365 		flow = ovs_flow_tbl_dump_next(ti, &bucket, &obj);
1366 		if (!flow)
1367 			break;
1368 
1369 		if (ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex, skb,
1370 					   NETLINK_CB(cb->skb).portid,
1371 					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
1372 					   OVS_FLOW_CMD_NEW, ufid_flags) < 0)
1373 			break;
1374 
1375 		cb->args[0] = bucket;
1376 		cb->args[1] = obj;
1377 	}
1378 	rcu_read_unlock();
1379 	return skb->len;
1380 }
1381 
1382 static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = {
1383 	[OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED },
1384 	[OVS_FLOW_ATTR_MASK] = { .type = NLA_NESTED },
1385 	[OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED },
1386 	[OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG },
1387 	[OVS_FLOW_ATTR_PROBE] = { .type = NLA_FLAG },
1388 	[OVS_FLOW_ATTR_UFID] = { .type = NLA_UNSPEC, .len = 1 },
1389 	[OVS_FLOW_ATTR_UFID_FLAGS] = { .type = NLA_U32 },
1390 };
1391 
1392 static const struct genl_ops dp_flow_genl_ops[] = {
1393 	{ .cmd = OVS_FLOW_CMD_NEW,
1394 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1395 	  .policy = flow_policy,
1396 	  .doit = ovs_flow_cmd_new
1397 	},
1398 	{ .cmd = OVS_FLOW_CMD_DEL,
1399 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1400 	  .policy = flow_policy,
1401 	  .doit = ovs_flow_cmd_del
1402 	},
1403 	{ .cmd = OVS_FLOW_CMD_GET,
1404 	  .flags = 0,		    /* OK for unprivileged users. */
1405 	  .policy = flow_policy,
1406 	  .doit = ovs_flow_cmd_get,
1407 	  .dumpit = ovs_flow_cmd_dump
1408 	},
1409 	{ .cmd = OVS_FLOW_CMD_SET,
1410 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1411 	  .policy = flow_policy,
1412 	  .doit = ovs_flow_cmd_set,
1413 	},
1414 };
1415 
1416 static struct genl_family dp_flow_genl_family = {
1417 	.id = GENL_ID_GENERATE,
1418 	.hdrsize = sizeof(struct ovs_header),
1419 	.name = OVS_FLOW_FAMILY,
1420 	.version = OVS_FLOW_VERSION,
1421 	.maxattr = OVS_FLOW_ATTR_MAX,
1422 	.netnsok = true,
1423 	.parallel_ops = true,
1424 	.ops = dp_flow_genl_ops,
1425 	.n_ops = ARRAY_SIZE(dp_flow_genl_ops),
1426 	.mcgrps = &ovs_dp_flow_multicast_group,
1427 	.n_mcgrps = 1,
1428 };
1429 
1430 static size_t ovs_dp_cmd_msg_size(void)
1431 {
1432 	size_t msgsize = NLMSG_ALIGN(sizeof(struct ovs_header));
1433 
1434 	msgsize += nla_total_size(IFNAMSIZ);
1435 	msgsize += nla_total_size(sizeof(struct ovs_dp_stats));
1436 	msgsize += nla_total_size(sizeof(struct ovs_dp_megaflow_stats));
1437 	msgsize += nla_total_size(sizeof(u32)); /* OVS_DP_ATTR_USER_FEATURES */
1438 
1439 	return msgsize;
1440 }
1441 
1442 /* Called with ovs_mutex. */
1443 static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
1444 				u32 portid, u32 seq, u32 flags, u8 cmd)
1445 {
1446 	struct ovs_header *ovs_header;
1447 	struct ovs_dp_stats dp_stats;
1448 	struct ovs_dp_megaflow_stats dp_megaflow_stats;
1449 	int err;
1450 
1451 	ovs_header = genlmsg_put(skb, portid, seq, &dp_datapath_genl_family,
1452 				   flags, cmd);
1453 	if (!ovs_header)
1454 		goto error;
1455 
1456 	ovs_header->dp_ifindex = get_dpifindex(dp);
1457 
1458 	err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp));
1459 	if (err)
1460 		goto nla_put_failure;
1461 
1462 	get_dp_stats(dp, &dp_stats, &dp_megaflow_stats);
1463 	if (nla_put(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats),
1464 			&dp_stats))
1465 		goto nla_put_failure;
1466 
1467 	if (nla_put(skb, OVS_DP_ATTR_MEGAFLOW_STATS,
1468 			sizeof(struct ovs_dp_megaflow_stats),
1469 			&dp_megaflow_stats))
1470 		goto nla_put_failure;
1471 
1472 	if (nla_put_u32(skb, OVS_DP_ATTR_USER_FEATURES, dp->user_features))
1473 		goto nla_put_failure;
1474 
1475 	genlmsg_end(skb, ovs_header);
1476 	return 0;
1477 
1478 nla_put_failure:
1479 	genlmsg_cancel(skb, ovs_header);
1480 error:
1481 	return -EMSGSIZE;
1482 }
1483 
1484 static struct sk_buff *ovs_dp_cmd_alloc_info(struct genl_info *info)
1485 {
1486 	return genlmsg_new_unicast(ovs_dp_cmd_msg_size(), info, GFP_KERNEL);
1487 }
1488 
1489 /* Called with rcu_read_lock or ovs_mutex. */
1490 static struct datapath *lookup_datapath(struct net *net,
1491 					const struct ovs_header *ovs_header,
1492 					struct nlattr *a[OVS_DP_ATTR_MAX + 1])
1493 {
1494 	struct datapath *dp;
1495 
1496 	if (!a[OVS_DP_ATTR_NAME])
1497 		dp = get_dp(net, ovs_header->dp_ifindex);
1498 	else {
1499 		struct vport *vport;
1500 
1501 		vport = ovs_vport_locate(net, nla_data(a[OVS_DP_ATTR_NAME]));
1502 		dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL;
1503 	}
1504 	return dp ? dp : ERR_PTR(-ENODEV);
1505 }
1506 
1507 static void ovs_dp_reset_user_features(struct sk_buff *skb, struct genl_info *info)
1508 {
1509 	struct datapath *dp;
1510 
1511 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1512 	if (IS_ERR(dp))
1513 		return;
1514 
1515 	WARN(dp->user_features, "Dropping previously announced user features\n");
1516 	dp->user_features = 0;
1517 }
1518 
1519 static void ovs_dp_change(struct datapath *dp, struct nlattr *a[])
1520 {
1521 	if (a[OVS_DP_ATTR_USER_FEATURES])
1522 		dp->user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
1523 }
1524 
1525 static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
1526 {
1527 	struct nlattr **a = info->attrs;
1528 	struct vport_parms parms;
1529 	struct sk_buff *reply;
1530 	struct datapath *dp;
1531 	struct vport *vport;
1532 	struct ovs_net *ovs_net;
1533 	int err, i;
1534 
1535 	err = -EINVAL;
1536 	if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
1537 		goto err;
1538 
1539 	reply = ovs_dp_cmd_alloc_info(info);
1540 	if (!reply)
1541 		return -ENOMEM;
1542 
1543 	err = -ENOMEM;
1544 	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
1545 	if (dp == NULL)
1546 		goto err_free_reply;
1547 
1548 	ovs_dp_set_net(dp, sock_net(skb->sk));
1549 
1550 	/* Allocate table. */
1551 	err = ovs_flow_tbl_init(&dp->table);
1552 	if (err)
1553 		goto err_free_dp;
1554 
1555 	dp->stats_percpu = netdev_alloc_pcpu_stats(struct dp_stats_percpu);
1556 	if (!dp->stats_percpu) {
1557 		err = -ENOMEM;
1558 		goto err_destroy_table;
1559 	}
1560 
1561 	dp->ports = kmalloc(DP_VPORT_HASH_BUCKETS * sizeof(struct hlist_head),
1562 			    GFP_KERNEL);
1563 	if (!dp->ports) {
1564 		err = -ENOMEM;
1565 		goto err_destroy_percpu;
1566 	}
1567 
1568 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
1569 		INIT_HLIST_HEAD(&dp->ports[i]);
1570 
1571 	/* Set up our datapath device. */
1572 	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
1573 	parms.type = OVS_VPORT_TYPE_INTERNAL;
1574 	parms.options = NULL;
1575 	parms.dp = dp;
1576 	parms.port_no = OVSP_LOCAL;
1577 	parms.upcall_portids = a[OVS_DP_ATTR_UPCALL_PID];
1578 
1579 	ovs_dp_change(dp, a);
1580 
1581 	/* So far only local changes have been made, now need the lock. */
1582 	ovs_lock();
1583 
1584 	vport = new_vport(&parms);
1585 	if (IS_ERR(vport)) {
1586 		err = PTR_ERR(vport);
1587 		if (err == -EBUSY)
1588 			err = -EEXIST;
1589 
1590 		if (err == -EEXIST) {
1591 			/* An outdated user space instance that does not understand
1592 			 * the concept of user_features has attempted to create a new
1593 			 * datapath and is likely to reuse it. Drop all user features.
1594 			 */
1595 			if (info->genlhdr->version < OVS_DP_VER_FEATURES)
1596 				ovs_dp_reset_user_features(skb, info);
1597 		}
1598 
1599 		goto err_destroy_ports_array;
1600 	}
1601 
1602 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1603 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1604 	BUG_ON(err < 0);
1605 
1606 	ovs_net = net_generic(ovs_dp_get_net(dp), ovs_net_id);
1607 	list_add_tail_rcu(&dp->list_node, &ovs_net->dps);
1608 
1609 	ovs_unlock();
1610 
1611 	ovs_notify(&dp_datapath_genl_family, reply, info);
1612 	return 0;
1613 
1614 err_destroy_ports_array:
1615 	ovs_unlock();
1616 	kfree(dp->ports);
1617 err_destroy_percpu:
1618 	free_percpu(dp->stats_percpu);
1619 err_destroy_table:
1620 	ovs_flow_tbl_destroy(&dp->table);
1621 err_free_dp:
1622 	kfree(dp);
1623 err_free_reply:
1624 	kfree_skb(reply);
1625 err:
1626 	return err;
1627 }
1628 
1629 /* Called with ovs_mutex. */
1630 static void __dp_destroy(struct datapath *dp)
1631 {
1632 	int i;
1633 
1634 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
1635 		struct vport *vport;
1636 		struct hlist_node *n;
1637 
1638 		hlist_for_each_entry_safe(vport, n, &dp->ports[i], dp_hash_node)
1639 			if (vport->port_no != OVSP_LOCAL)
1640 				ovs_dp_detach_port(vport);
1641 	}
1642 
1643 	list_del_rcu(&dp->list_node);
1644 
1645 	/* OVSP_LOCAL is datapath internal port. We need to make sure that
1646 	 * all ports in datapath are destroyed first before freeing datapath.
1647 	 */
1648 	ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
1649 
1650 	/* RCU destroy the flow table */
1651 	call_rcu(&dp->rcu, destroy_dp_rcu);
1652 }
1653 
1654 static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
1655 {
1656 	struct sk_buff *reply;
1657 	struct datapath *dp;
1658 	int err;
1659 
1660 	reply = ovs_dp_cmd_alloc_info(info);
1661 	if (!reply)
1662 		return -ENOMEM;
1663 
1664 	ovs_lock();
1665 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1666 	err = PTR_ERR(dp);
1667 	if (IS_ERR(dp))
1668 		goto err_unlock_free;
1669 
1670 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1671 				   info->snd_seq, 0, OVS_DP_CMD_DEL);
1672 	BUG_ON(err < 0);
1673 
1674 	__dp_destroy(dp);
1675 	ovs_unlock();
1676 
1677 	ovs_notify(&dp_datapath_genl_family, reply, info);
1678 
1679 	return 0;
1680 
1681 err_unlock_free:
1682 	ovs_unlock();
1683 	kfree_skb(reply);
1684 	return err;
1685 }
1686 
1687 static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
1688 {
1689 	struct sk_buff *reply;
1690 	struct datapath *dp;
1691 	int err;
1692 
1693 	reply = ovs_dp_cmd_alloc_info(info);
1694 	if (!reply)
1695 		return -ENOMEM;
1696 
1697 	ovs_lock();
1698 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1699 	err = PTR_ERR(dp);
1700 	if (IS_ERR(dp))
1701 		goto err_unlock_free;
1702 
1703 	ovs_dp_change(dp, info->attrs);
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 
1709 	ovs_unlock();
1710 	ovs_notify(&dp_datapath_genl_family, reply, info);
1711 
1712 	return 0;
1713 
1714 err_unlock_free:
1715 	ovs_unlock();
1716 	kfree_skb(reply);
1717 	return err;
1718 }
1719 
1720 static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
1721 {
1722 	struct sk_buff *reply;
1723 	struct datapath *dp;
1724 	int err;
1725 
1726 	reply = ovs_dp_cmd_alloc_info(info);
1727 	if (!reply)
1728 		return -ENOMEM;
1729 
1730 	ovs_lock();
1731 	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
1732 	if (IS_ERR(dp)) {
1733 		err = PTR_ERR(dp);
1734 		goto err_unlock_free;
1735 	}
1736 	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
1737 				   info->snd_seq, 0, OVS_DP_CMD_NEW);
1738 	BUG_ON(err < 0);
1739 	ovs_unlock();
1740 
1741 	return genlmsg_reply(reply, info);
1742 
1743 err_unlock_free:
1744 	ovs_unlock();
1745 	kfree_skb(reply);
1746 	return err;
1747 }
1748 
1749 static int ovs_dp_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
1750 {
1751 	struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
1752 	struct datapath *dp;
1753 	int skip = cb->args[0];
1754 	int i = 0;
1755 
1756 	ovs_lock();
1757 	list_for_each_entry(dp, &ovs_net->dps, list_node) {
1758 		if (i >= skip &&
1759 		    ovs_dp_cmd_fill_info(dp, skb, NETLINK_CB(cb->skb).portid,
1760 					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1761 					 OVS_DP_CMD_NEW) < 0)
1762 			break;
1763 		i++;
1764 	}
1765 	ovs_unlock();
1766 
1767 	cb->args[0] = i;
1768 
1769 	return skb->len;
1770 }
1771 
1772 static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
1773 	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
1774 	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
1775 	[OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 },
1776 };
1777 
1778 static const struct genl_ops dp_datapath_genl_ops[] = {
1779 	{ .cmd = OVS_DP_CMD_NEW,
1780 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1781 	  .policy = datapath_policy,
1782 	  .doit = ovs_dp_cmd_new
1783 	},
1784 	{ .cmd = OVS_DP_CMD_DEL,
1785 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1786 	  .policy = datapath_policy,
1787 	  .doit = ovs_dp_cmd_del
1788 	},
1789 	{ .cmd = OVS_DP_CMD_GET,
1790 	  .flags = 0,		    /* OK for unprivileged users. */
1791 	  .policy = datapath_policy,
1792 	  .doit = ovs_dp_cmd_get,
1793 	  .dumpit = ovs_dp_cmd_dump
1794 	},
1795 	{ .cmd = OVS_DP_CMD_SET,
1796 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
1797 	  .policy = datapath_policy,
1798 	  .doit = ovs_dp_cmd_set,
1799 	},
1800 };
1801 
1802 static struct genl_family dp_datapath_genl_family = {
1803 	.id = GENL_ID_GENERATE,
1804 	.hdrsize = sizeof(struct ovs_header),
1805 	.name = OVS_DATAPATH_FAMILY,
1806 	.version = OVS_DATAPATH_VERSION,
1807 	.maxattr = OVS_DP_ATTR_MAX,
1808 	.netnsok = true,
1809 	.parallel_ops = true,
1810 	.ops = dp_datapath_genl_ops,
1811 	.n_ops = ARRAY_SIZE(dp_datapath_genl_ops),
1812 	.mcgrps = &ovs_dp_datapath_multicast_group,
1813 	.n_mcgrps = 1,
1814 };
1815 
1816 /* Called with ovs_mutex or RCU read lock. */
1817 static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
1818 				   u32 portid, u32 seq, u32 flags, u8 cmd)
1819 {
1820 	struct ovs_header *ovs_header;
1821 	struct ovs_vport_stats vport_stats;
1822 	int err;
1823 
1824 	ovs_header = genlmsg_put(skb, portid, seq, &dp_vport_genl_family,
1825 				 flags, cmd);
1826 	if (!ovs_header)
1827 		return -EMSGSIZE;
1828 
1829 	ovs_header->dp_ifindex = get_dpifindex(vport->dp);
1830 
1831 	if (nla_put_u32(skb, OVS_VPORT_ATTR_PORT_NO, vport->port_no) ||
1832 	    nla_put_u32(skb, OVS_VPORT_ATTR_TYPE, vport->ops->type) ||
1833 	    nla_put_string(skb, OVS_VPORT_ATTR_NAME,
1834 			   ovs_vport_name(vport)))
1835 		goto nla_put_failure;
1836 
1837 	ovs_vport_get_stats(vport, &vport_stats);
1838 	if (nla_put(skb, OVS_VPORT_ATTR_STATS, sizeof(struct ovs_vport_stats),
1839 		    &vport_stats))
1840 		goto nla_put_failure;
1841 
1842 	if (ovs_vport_get_upcall_portids(vport, skb))
1843 		goto nla_put_failure;
1844 
1845 	err = ovs_vport_get_options(vport, skb);
1846 	if (err == -EMSGSIZE)
1847 		goto error;
1848 
1849 	genlmsg_end(skb, ovs_header);
1850 	return 0;
1851 
1852 nla_put_failure:
1853 	err = -EMSGSIZE;
1854 error:
1855 	genlmsg_cancel(skb, ovs_header);
1856 	return err;
1857 }
1858 
1859 static struct sk_buff *ovs_vport_cmd_alloc_info(void)
1860 {
1861 	return nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1862 }
1863 
1864 /* Called with ovs_mutex, only via ovs_dp_notify_wq(). */
1865 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, u32 portid,
1866 					 u32 seq, u8 cmd)
1867 {
1868 	struct sk_buff *skb;
1869 	int retval;
1870 
1871 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1872 	if (!skb)
1873 		return ERR_PTR(-ENOMEM);
1874 
1875 	retval = ovs_vport_cmd_fill_info(vport, skb, portid, seq, 0, cmd);
1876 	BUG_ON(retval < 0);
1877 
1878 	return skb;
1879 }
1880 
1881 /* Called with ovs_mutex or RCU read lock. */
1882 static struct vport *lookup_vport(struct net *net,
1883 				  const struct ovs_header *ovs_header,
1884 				  struct nlattr *a[OVS_VPORT_ATTR_MAX + 1])
1885 {
1886 	struct datapath *dp;
1887 	struct vport *vport;
1888 
1889 	if (a[OVS_VPORT_ATTR_NAME]) {
1890 		vport = ovs_vport_locate(net, nla_data(a[OVS_VPORT_ATTR_NAME]));
1891 		if (!vport)
1892 			return ERR_PTR(-ENODEV);
1893 		if (ovs_header->dp_ifindex &&
1894 		    ovs_header->dp_ifindex != get_dpifindex(vport->dp))
1895 			return ERR_PTR(-ENODEV);
1896 		return vport;
1897 	} else if (a[OVS_VPORT_ATTR_PORT_NO]) {
1898 		u32 port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
1899 
1900 		if (port_no >= DP_MAX_PORTS)
1901 			return ERR_PTR(-EFBIG);
1902 
1903 		dp = get_dp(net, ovs_header->dp_ifindex);
1904 		if (!dp)
1905 			return ERR_PTR(-ENODEV);
1906 
1907 		vport = ovs_vport_ovsl_rcu(dp, port_no);
1908 		if (!vport)
1909 			return ERR_PTR(-ENODEV);
1910 		return vport;
1911 	} else
1912 		return ERR_PTR(-EINVAL);
1913 }
1914 
1915 static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
1916 {
1917 	struct nlattr **a = info->attrs;
1918 	struct ovs_header *ovs_header = info->userhdr;
1919 	struct vport_parms parms;
1920 	struct sk_buff *reply;
1921 	struct vport *vport;
1922 	struct datapath *dp;
1923 	u32 port_no;
1924 	int err;
1925 
1926 	if (!a[OVS_VPORT_ATTR_NAME] || !a[OVS_VPORT_ATTR_TYPE] ||
1927 	    !a[OVS_VPORT_ATTR_UPCALL_PID])
1928 		return -EINVAL;
1929 
1930 	port_no = a[OVS_VPORT_ATTR_PORT_NO]
1931 		? nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]) : 0;
1932 	if (port_no >= DP_MAX_PORTS)
1933 		return -EFBIG;
1934 
1935 	reply = ovs_vport_cmd_alloc_info();
1936 	if (!reply)
1937 		return -ENOMEM;
1938 
1939 	ovs_lock();
1940 restart:
1941 	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
1942 	err = -ENODEV;
1943 	if (!dp)
1944 		goto exit_unlock_free;
1945 
1946 	if (port_no) {
1947 		vport = ovs_vport_ovsl(dp, port_no);
1948 		err = -EBUSY;
1949 		if (vport)
1950 			goto exit_unlock_free;
1951 	} else {
1952 		for (port_no = 1; ; port_no++) {
1953 			if (port_no >= DP_MAX_PORTS) {
1954 				err = -EFBIG;
1955 				goto exit_unlock_free;
1956 			}
1957 			vport = ovs_vport_ovsl(dp, port_no);
1958 			if (!vport)
1959 				break;
1960 		}
1961 	}
1962 
1963 	parms.name = nla_data(a[OVS_VPORT_ATTR_NAME]);
1964 	parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
1965 	parms.options = a[OVS_VPORT_ATTR_OPTIONS];
1966 	parms.dp = dp;
1967 	parms.port_no = port_no;
1968 	parms.upcall_portids = a[OVS_VPORT_ATTR_UPCALL_PID];
1969 
1970 	vport = new_vport(&parms);
1971 	err = PTR_ERR(vport);
1972 	if (IS_ERR(vport)) {
1973 		if (err == -EAGAIN)
1974 			goto restart;
1975 		goto exit_unlock_free;
1976 	}
1977 
1978 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
1979 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
1980 	BUG_ON(err < 0);
1981 	ovs_unlock();
1982 
1983 	ovs_notify(&dp_vport_genl_family, reply, info);
1984 	return 0;
1985 
1986 exit_unlock_free:
1987 	ovs_unlock();
1988 	kfree_skb(reply);
1989 	return err;
1990 }
1991 
1992 static int ovs_vport_cmd_set(struct sk_buff *skb, struct genl_info *info)
1993 {
1994 	struct nlattr **a = info->attrs;
1995 	struct sk_buff *reply;
1996 	struct vport *vport;
1997 	int err;
1998 
1999 	reply = ovs_vport_cmd_alloc_info();
2000 	if (!reply)
2001 		return -ENOMEM;
2002 
2003 	ovs_lock();
2004 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
2005 	err = PTR_ERR(vport);
2006 	if (IS_ERR(vport))
2007 		goto exit_unlock_free;
2008 
2009 	if (a[OVS_VPORT_ATTR_TYPE] &&
2010 	    nla_get_u32(a[OVS_VPORT_ATTR_TYPE]) != vport->ops->type) {
2011 		err = -EINVAL;
2012 		goto exit_unlock_free;
2013 	}
2014 
2015 	if (a[OVS_VPORT_ATTR_OPTIONS]) {
2016 		err = ovs_vport_set_options(vport, a[OVS_VPORT_ATTR_OPTIONS]);
2017 		if (err)
2018 			goto exit_unlock_free;
2019 	}
2020 
2021 
2022 	if (a[OVS_VPORT_ATTR_UPCALL_PID]) {
2023 		struct nlattr *ids = a[OVS_VPORT_ATTR_UPCALL_PID];
2024 
2025 		err = ovs_vport_set_upcall_portids(vport, ids);
2026 		if (err)
2027 			goto exit_unlock_free;
2028 	}
2029 
2030 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2031 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
2032 	BUG_ON(err < 0);
2033 
2034 	ovs_unlock();
2035 	ovs_notify(&dp_vport_genl_family, reply, info);
2036 	return 0;
2037 
2038 exit_unlock_free:
2039 	ovs_unlock();
2040 	kfree_skb(reply);
2041 	return err;
2042 }
2043 
2044 static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info)
2045 {
2046 	struct nlattr **a = info->attrs;
2047 	struct sk_buff *reply;
2048 	struct vport *vport;
2049 	int err;
2050 
2051 	reply = ovs_vport_cmd_alloc_info();
2052 	if (!reply)
2053 		return -ENOMEM;
2054 
2055 	ovs_lock();
2056 	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
2057 	err = PTR_ERR(vport);
2058 	if (IS_ERR(vport))
2059 		goto exit_unlock_free;
2060 
2061 	if (vport->port_no == OVSP_LOCAL) {
2062 		err = -EINVAL;
2063 		goto exit_unlock_free;
2064 	}
2065 
2066 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2067 				      info->snd_seq, 0, OVS_VPORT_CMD_DEL);
2068 	BUG_ON(err < 0);
2069 	ovs_dp_detach_port(vport);
2070 	ovs_unlock();
2071 
2072 	ovs_notify(&dp_vport_genl_family, reply, info);
2073 	return 0;
2074 
2075 exit_unlock_free:
2076 	ovs_unlock();
2077 	kfree_skb(reply);
2078 	return err;
2079 }
2080 
2081 static int ovs_vport_cmd_get(struct sk_buff *skb, struct genl_info *info)
2082 {
2083 	struct nlattr **a = info->attrs;
2084 	struct ovs_header *ovs_header = info->userhdr;
2085 	struct sk_buff *reply;
2086 	struct vport *vport;
2087 	int err;
2088 
2089 	reply = ovs_vport_cmd_alloc_info();
2090 	if (!reply)
2091 		return -ENOMEM;
2092 
2093 	rcu_read_lock();
2094 	vport = lookup_vport(sock_net(skb->sk), ovs_header, a);
2095 	err = PTR_ERR(vport);
2096 	if (IS_ERR(vport))
2097 		goto exit_unlock_free;
2098 	err = ovs_vport_cmd_fill_info(vport, reply, info->snd_portid,
2099 				      info->snd_seq, 0, OVS_VPORT_CMD_NEW);
2100 	BUG_ON(err < 0);
2101 	rcu_read_unlock();
2102 
2103 	return genlmsg_reply(reply, info);
2104 
2105 exit_unlock_free:
2106 	rcu_read_unlock();
2107 	kfree_skb(reply);
2108 	return err;
2109 }
2110 
2111 static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
2112 {
2113 	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
2114 	struct datapath *dp;
2115 	int bucket = cb->args[0], skip = cb->args[1];
2116 	int i, j = 0;
2117 
2118 	rcu_read_lock();
2119 	dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex);
2120 	if (!dp) {
2121 		rcu_read_unlock();
2122 		return -ENODEV;
2123 	}
2124 	for (i = bucket; i < DP_VPORT_HASH_BUCKETS; i++) {
2125 		struct vport *vport;
2126 
2127 		j = 0;
2128 		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) {
2129 			if (j >= skip &&
2130 			    ovs_vport_cmd_fill_info(vport, skb,
2131 						    NETLINK_CB(cb->skb).portid,
2132 						    cb->nlh->nlmsg_seq,
2133 						    NLM_F_MULTI,
2134 						    OVS_VPORT_CMD_NEW) < 0)
2135 				goto out;
2136 
2137 			j++;
2138 		}
2139 		skip = 0;
2140 	}
2141 out:
2142 	rcu_read_unlock();
2143 
2144 	cb->args[0] = i;
2145 	cb->args[1] = j;
2146 
2147 	return skb->len;
2148 }
2149 
2150 static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
2151 	[OVS_VPORT_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
2152 	[OVS_VPORT_ATTR_STATS] = { .len = sizeof(struct ovs_vport_stats) },
2153 	[OVS_VPORT_ATTR_PORT_NO] = { .type = NLA_U32 },
2154 	[OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 },
2155 	[OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_U32 },
2156 	[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
2157 };
2158 
2159 static const struct genl_ops dp_vport_genl_ops[] = {
2160 	{ .cmd = OVS_VPORT_CMD_NEW,
2161 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2162 	  .policy = vport_policy,
2163 	  .doit = ovs_vport_cmd_new
2164 	},
2165 	{ .cmd = OVS_VPORT_CMD_DEL,
2166 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2167 	  .policy = vport_policy,
2168 	  .doit = ovs_vport_cmd_del
2169 	},
2170 	{ .cmd = OVS_VPORT_CMD_GET,
2171 	  .flags = 0,		    /* OK for unprivileged users. */
2172 	  .policy = vport_policy,
2173 	  .doit = ovs_vport_cmd_get,
2174 	  .dumpit = ovs_vport_cmd_dump
2175 	},
2176 	{ .cmd = OVS_VPORT_CMD_SET,
2177 	  .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
2178 	  .policy = vport_policy,
2179 	  .doit = ovs_vport_cmd_set,
2180 	},
2181 };
2182 
2183 struct genl_family dp_vport_genl_family = {
2184 	.id = GENL_ID_GENERATE,
2185 	.hdrsize = sizeof(struct ovs_header),
2186 	.name = OVS_VPORT_FAMILY,
2187 	.version = OVS_VPORT_VERSION,
2188 	.maxattr = OVS_VPORT_ATTR_MAX,
2189 	.netnsok = true,
2190 	.parallel_ops = true,
2191 	.ops = dp_vport_genl_ops,
2192 	.n_ops = ARRAY_SIZE(dp_vport_genl_ops),
2193 	.mcgrps = &ovs_dp_vport_multicast_group,
2194 	.n_mcgrps = 1,
2195 };
2196 
2197 static struct genl_family * const dp_genl_families[] = {
2198 	&dp_datapath_genl_family,
2199 	&dp_vport_genl_family,
2200 	&dp_flow_genl_family,
2201 	&dp_packet_genl_family,
2202 };
2203 
2204 static void dp_unregister_genl(int n_families)
2205 {
2206 	int i;
2207 
2208 	for (i = 0; i < n_families; i++)
2209 		genl_unregister_family(dp_genl_families[i]);
2210 }
2211 
2212 static int dp_register_genl(void)
2213 {
2214 	int err;
2215 	int i;
2216 
2217 	for (i = 0; i < ARRAY_SIZE(dp_genl_families); i++) {
2218 
2219 		err = genl_register_family(dp_genl_families[i]);
2220 		if (err)
2221 			goto error;
2222 	}
2223 
2224 	return 0;
2225 
2226 error:
2227 	dp_unregister_genl(i);
2228 	return err;
2229 }
2230 
2231 static int __net_init ovs_init_net(struct net *net)
2232 {
2233 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2234 
2235 	INIT_LIST_HEAD(&ovs_net->dps);
2236 	INIT_WORK(&ovs_net->dp_notify_work, ovs_dp_notify_wq);
2237 	ovs_ct_init(net);
2238 	return 0;
2239 }
2240 
2241 static void __net_exit list_vports_from_net(struct net *net, struct net *dnet,
2242 					    struct list_head *head)
2243 {
2244 	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2245 	struct datapath *dp;
2246 
2247 	list_for_each_entry(dp, &ovs_net->dps, list_node) {
2248 		int i;
2249 
2250 		for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
2251 			struct vport *vport;
2252 
2253 			hlist_for_each_entry(vport, &dp->ports[i], dp_hash_node) {
2254 				if (vport->ops->type != OVS_VPORT_TYPE_INTERNAL)
2255 					continue;
2256 
2257 				if (dev_net(vport->dev) == dnet)
2258 					list_add(&vport->detach_list, head);
2259 			}
2260 		}
2261 	}
2262 }
2263 
2264 static void __net_exit ovs_exit_net(struct net *dnet)
2265 {
2266 	struct datapath *dp, *dp_next;
2267 	struct ovs_net *ovs_net = net_generic(dnet, ovs_net_id);
2268 	struct vport *vport, *vport_next;
2269 	struct net *net;
2270 	LIST_HEAD(head);
2271 
2272 	ovs_ct_exit(dnet);
2273 	ovs_lock();
2274 	list_for_each_entry_safe(dp, dp_next, &ovs_net->dps, list_node)
2275 		__dp_destroy(dp);
2276 
2277 	rtnl_lock();
2278 	for_each_net(net)
2279 		list_vports_from_net(net, dnet, &head);
2280 	rtnl_unlock();
2281 
2282 	/* Detach all vports from given namespace. */
2283 	list_for_each_entry_safe(vport, vport_next, &head, detach_list) {
2284 		list_del(&vport->detach_list);
2285 		ovs_dp_detach_port(vport);
2286 	}
2287 
2288 	ovs_unlock();
2289 
2290 	cancel_work_sync(&ovs_net->dp_notify_work);
2291 }
2292 
2293 static struct pernet_operations ovs_net_ops = {
2294 	.init = ovs_init_net,
2295 	.exit = ovs_exit_net,
2296 	.id   = &ovs_net_id,
2297 	.size = sizeof(struct ovs_net),
2298 };
2299 
2300 static int __init dp_init(void)
2301 {
2302 	int err;
2303 
2304 	BUILD_BUG_ON(sizeof(struct ovs_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb));
2305 
2306 	pr_info("Open vSwitch switching datapath\n");
2307 
2308 	err = action_fifos_init();
2309 	if (err)
2310 		goto error;
2311 
2312 	err = ovs_internal_dev_rtnl_link_register();
2313 	if (err)
2314 		goto error_action_fifos_exit;
2315 
2316 	err = ovs_flow_init();
2317 	if (err)
2318 		goto error_unreg_rtnl_link;
2319 
2320 	err = ovs_vport_init();
2321 	if (err)
2322 		goto error_flow_exit;
2323 
2324 	err = register_pernet_device(&ovs_net_ops);
2325 	if (err)
2326 		goto error_vport_exit;
2327 
2328 	err = register_netdevice_notifier(&ovs_dp_device_notifier);
2329 	if (err)
2330 		goto error_netns_exit;
2331 
2332 	err = ovs_netdev_init();
2333 	if (err)
2334 		goto error_unreg_notifier;
2335 
2336 	err = dp_register_genl();
2337 	if (err < 0)
2338 		goto error_unreg_netdev;
2339 
2340 	return 0;
2341 
2342 error_unreg_netdev:
2343 	ovs_netdev_exit();
2344 error_unreg_notifier:
2345 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2346 error_netns_exit:
2347 	unregister_pernet_device(&ovs_net_ops);
2348 error_vport_exit:
2349 	ovs_vport_exit();
2350 error_flow_exit:
2351 	ovs_flow_exit();
2352 error_unreg_rtnl_link:
2353 	ovs_internal_dev_rtnl_link_unregister();
2354 error_action_fifos_exit:
2355 	action_fifos_exit();
2356 error:
2357 	return err;
2358 }
2359 
2360 static void dp_cleanup(void)
2361 {
2362 	dp_unregister_genl(ARRAY_SIZE(dp_genl_families));
2363 	ovs_netdev_exit();
2364 	unregister_netdevice_notifier(&ovs_dp_device_notifier);
2365 	unregister_pernet_device(&ovs_net_ops);
2366 	rcu_barrier();
2367 	ovs_vport_exit();
2368 	ovs_flow_exit();
2369 	ovs_internal_dev_rtnl_link_unregister();
2370 	action_fifos_exit();
2371 }
2372 
2373 module_init(dp_init);
2374 module_exit(dp_cleanup);
2375 
2376 MODULE_DESCRIPTION("Open vSwitch switching datapath");
2377 MODULE_LICENSE("GPL");
2378