xref: /openbmc/linux/net/openvswitch/actions.c (revision 612a462a)
1 /*
2  * Copyright (c) 2007-2017 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/skbuff.h>
22 #include <linux/in.h>
23 #include <linux/ip.h>
24 #include <linux/openvswitch.h>
25 #include <linux/netfilter_ipv6.h>
26 #include <linux/sctp.h>
27 #include <linux/tcp.h>
28 #include <linux/udp.h>
29 #include <linux/in6.h>
30 #include <linux/if_arp.h>
31 #include <linux/if_vlan.h>
32 
33 #include <net/dst.h>
34 #include <net/ip.h>
35 #include <net/ipv6.h>
36 #include <net/ip6_fib.h>
37 #include <net/checksum.h>
38 #include <net/dsfield.h>
39 #include <net/mpls.h>
40 #include <net/sctp/checksum.h>
41 
42 #include "datapath.h"
43 #include "flow.h"
44 #include "conntrack.h"
45 #include "vport.h"
46 
47 struct deferred_action {
48 	struct sk_buff *skb;
49 	const struct nlattr *actions;
50 	int actions_len;
51 
52 	/* Store pkt_key clone when creating deferred action. */
53 	struct sw_flow_key pkt_key;
54 };
55 
56 #define MAX_L2_LEN	(VLAN_ETH_HLEN + 3 * MPLS_HLEN)
57 struct ovs_frag_data {
58 	unsigned long dst;
59 	struct vport *vport;
60 	struct ovs_skb_cb cb;
61 	__be16 inner_protocol;
62 	u16 network_offset;	/* valid only for MPLS */
63 	u16 vlan_tci;
64 	__be16 vlan_proto;
65 	unsigned int l2_len;
66 	u8 mac_proto;
67 	u8 l2_data[MAX_L2_LEN];
68 };
69 
70 static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);
71 
72 #define DEFERRED_ACTION_FIFO_SIZE 10
73 #define OVS_RECURSION_LIMIT 5
74 #define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
75 struct action_fifo {
76 	int head;
77 	int tail;
78 	/* Deferred action fifo queue storage. */
79 	struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
80 };
81 
82 struct action_flow_keys {
83 	struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
84 };
85 
86 static struct action_fifo __percpu *action_fifos;
87 static struct action_flow_keys __percpu *flow_keys;
88 static DEFINE_PER_CPU(int, exec_actions_level);
89 
90 /* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys'
91  * space. Return NULL if out of key spaces.
92  */
93 static struct sw_flow_key *clone_key(const struct sw_flow_key *key_)
94 {
95 	struct action_flow_keys *keys = this_cpu_ptr(flow_keys);
96 	int level = this_cpu_read(exec_actions_level);
97 	struct sw_flow_key *key = NULL;
98 
99 	if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
100 		key = &keys->key[level - 1];
101 		*key = *key_;
102 	}
103 
104 	return key;
105 }
106 
107 static void action_fifo_init(struct action_fifo *fifo)
108 {
109 	fifo->head = 0;
110 	fifo->tail = 0;
111 }
112 
113 static bool action_fifo_is_empty(const struct action_fifo *fifo)
114 {
115 	return (fifo->head == fifo->tail);
116 }
117 
118 static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
119 {
120 	if (action_fifo_is_empty(fifo))
121 		return NULL;
122 
123 	return &fifo->fifo[fifo->tail++];
124 }
125 
126 static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
127 {
128 	if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
129 		return NULL;
130 
131 	return &fifo->fifo[fifo->head++];
132 }
133 
134 /* Return true if fifo is not full */
135 static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
136 				    const struct sw_flow_key *key,
137 				    const struct nlattr *actions,
138 				    const int actions_len)
139 {
140 	struct action_fifo *fifo;
141 	struct deferred_action *da;
142 
143 	fifo = this_cpu_ptr(action_fifos);
144 	da = action_fifo_put(fifo);
145 	if (da) {
146 		da->skb = skb;
147 		da->actions = actions;
148 		da->actions_len = actions_len;
149 		da->pkt_key = *key;
150 	}
151 
152 	return da;
153 }
154 
155 static void invalidate_flow_key(struct sw_flow_key *key)
156 {
157 	key->mac_proto |= SW_FLOW_KEY_INVALID;
158 }
159 
160 static bool is_flow_key_valid(const struct sw_flow_key *key)
161 {
162 	return !(key->mac_proto & SW_FLOW_KEY_INVALID);
163 }
164 
165 static int clone_execute(struct datapath *dp, struct sk_buff *skb,
166 			 struct sw_flow_key *key,
167 			 u32 recirc_id,
168 			 const struct nlattr *actions, int len,
169 			 bool last, bool clone_flow_key);
170 
171 static void update_ethertype(struct sk_buff *skb, struct ethhdr *hdr,
172 			     __be16 ethertype)
173 {
174 	if (skb->ip_summed == CHECKSUM_COMPLETE) {
175 		__be16 diff[] = { ~(hdr->h_proto), ethertype };
176 
177 		skb->csum = ~csum_partial((char *)diff, sizeof(diff),
178 					~skb->csum);
179 	}
180 
181 	hdr->h_proto = ethertype;
182 }
183 
184 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
185 		     const struct ovs_action_push_mpls *mpls)
186 {
187 	struct mpls_shim_hdr *new_mpls_lse;
188 
189 	/* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */
190 	if (skb->encapsulation)
191 		return -ENOTSUPP;
192 
193 	if (skb_cow_head(skb, MPLS_HLEN) < 0)
194 		return -ENOMEM;
195 
196 	if (!skb->inner_protocol) {
197 		skb_set_inner_network_header(skb, skb->mac_len);
198 		skb_set_inner_protocol(skb, skb->protocol);
199 	}
200 
201 	skb_push(skb, MPLS_HLEN);
202 	memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb),
203 		skb->mac_len);
204 	skb_reset_mac_header(skb);
205 	skb_set_network_header(skb, skb->mac_len);
206 
207 	new_mpls_lse = mpls_hdr(skb);
208 	new_mpls_lse->label_stack_entry = mpls->mpls_lse;
209 
210 	skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN);
211 
212 	if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET)
213 		update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype);
214 	skb->protocol = mpls->mpls_ethertype;
215 
216 	invalidate_flow_key(key);
217 	return 0;
218 }
219 
220 static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
221 		    const __be16 ethertype)
222 {
223 	int err;
224 
225 	err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
226 	if (unlikely(err))
227 		return err;
228 
229 	skb_postpull_rcsum(skb, mpls_hdr(skb), MPLS_HLEN);
230 
231 	memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb),
232 		skb->mac_len);
233 
234 	__skb_pull(skb, MPLS_HLEN);
235 	skb_reset_mac_header(skb);
236 	skb_set_network_header(skb, skb->mac_len);
237 
238 	if (ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET) {
239 		struct ethhdr *hdr;
240 
241 		/* mpls_hdr() is used to locate the ethertype field correctly in the
242 		 * presence of VLAN tags.
243 		 */
244 		hdr = (struct ethhdr *)((void *)mpls_hdr(skb) - ETH_HLEN);
245 		update_ethertype(skb, hdr, ethertype);
246 	}
247 	if (eth_p_mpls(skb->protocol))
248 		skb->protocol = ethertype;
249 
250 	invalidate_flow_key(key);
251 	return 0;
252 }
253 
254 static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
255 		    const __be32 *mpls_lse, const __be32 *mask)
256 {
257 	struct mpls_shim_hdr *stack;
258 	__be32 lse;
259 	int err;
260 
261 	err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
262 	if (unlikely(err))
263 		return err;
264 
265 	stack = mpls_hdr(skb);
266 	lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
267 	if (skb->ip_summed == CHECKSUM_COMPLETE) {
268 		__be32 diff[] = { ~(stack->label_stack_entry), lse };
269 
270 		skb->csum = ~csum_partial((char *)diff, sizeof(diff),
271 					  ~skb->csum);
272 	}
273 
274 	stack->label_stack_entry = lse;
275 	flow_key->mpls.top_lse = lse;
276 	return 0;
277 }
278 
279 static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
280 {
281 	int err;
282 
283 	err = skb_vlan_pop(skb);
284 	if (skb_vlan_tag_present(skb)) {
285 		invalidate_flow_key(key);
286 	} else {
287 		key->eth.vlan.tci = 0;
288 		key->eth.vlan.tpid = 0;
289 	}
290 	return err;
291 }
292 
293 static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
294 		     const struct ovs_action_push_vlan *vlan)
295 {
296 	if (skb_vlan_tag_present(skb)) {
297 		invalidate_flow_key(key);
298 	} else {
299 		key->eth.vlan.tci = vlan->vlan_tci;
300 		key->eth.vlan.tpid = vlan->vlan_tpid;
301 	}
302 	return skb_vlan_push(skb, vlan->vlan_tpid,
303 			     ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
304 }
305 
306 /* 'src' is already properly masked. */
307 static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
308 {
309 	u16 *dst = (u16 *)dst_;
310 	const u16 *src = (const u16 *)src_;
311 	const u16 *mask = (const u16 *)mask_;
312 
313 	OVS_SET_MASKED(dst[0], src[0], mask[0]);
314 	OVS_SET_MASKED(dst[1], src[1], mask[1]);
315 	OVS_SET_MASKED(dst[2], src[2], mask[2]);
316 }
317 
318 static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
319 			const struct ovs_key_ethernet *key,
320 			const struct ovs_key_ethernet *mask)
321 {
322 	int err;
323 
324 	err = skb_ensure_writable(skb, ETH_HLEN);
325 	if (unlikely(err))
326 		return err;
327 
328 	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
329 
330 	ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
331 			       mask->eth_src);
332 	ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
333 			       mask->eth_dst);
334 
335 	skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
336 
337 	ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
338 	ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
339 	return 0;
340 }
341 
342 /* pop_eth does not support VLAN packets as this action is never called
343  * for them.
344  */
345 static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
346 {
347 	skb_pull_rcsum(skb, ETH_HLEN);
348 	skb_reset_mac_header(skb);
349 	skb_reset_mac_len(skb);
350 
351 	/* safe right before invalidate_flow_key */
352 	key->mac_proto = MAC_PROTO_NONE;
353 	invalidate_flow_key(key);
354 	return 0;
355 }
356 
357 static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
358 		    const struct ovs_action_push_eth *ethh)
359 {
360 	struct ethhdr *hdr;
361 
362 	/* Add the new Ethernet header */
363 	if (skb_cow_head(skb, ETH_HLEN) < 0)
364 		return -ENOMEM;
365 
366 	skb_push(skb, ETH_HLEN);
367 	skb_reset_mac_header(skb);
368 	skb_reset_mac_len(skb);
369 
370 	hdr = eth_hdr(skb);
371 	ether_addr_copy(hdr->h_source, ethh->addresses.eth_src);
372 	ether_addr_copy(hdr->h_dest, ethh->addresses.eth_dst);
373 	hdr->h_proto = skb->protocol;
374 
375 	skb_postpush_rcsum(skb, hdr, ETH_HLEN);
376 
377 	/* safe right before invalidate_flow_key */
378 	key->mac_proto = MAC_PROTO_ETHERNET;
379 	invalidate_flow_key(key);
380 	return 0;
381 }
382 
383 static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
384 				  __be32 addr, __be32 new_addr)
385 {
386 	int transport_len = skb->len - skb_transport_offset(skb);
387 
388 	if (nh->frag_off & htons(IP_OFFSET))
389 		return;
390 
391 	if (nh->protocol == IPPROTO_TCP) {
392 		if (likely(transport_len >= sizeof(struct tcphdr)))
393 			inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
394 						 addr, new_addr, true);
395 	} else if (nh->protocol == IPPROTO_UDP) {
396 		if (likely(transport_len >= sizeof(struct udphdr))) {
397 			struct udphdr *uh = udp_hdr(skb);
398 
399 			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
400 				inet_proto_csum_replace4(&uh->check, skb,
401 							 addr, new_addr, true);
402 				if (!uh->check)
403 					uh->check = CSUM_MANGLED_0;
404 			}
405 		}
406 	}
407 }
408 
409 static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
410 			__be32 *addr, __be32 new_addr)
411 {
412 	update_ip_l4_checksum(skb, nh, *addr, new_addr);
413 	csum_replace4(&nh->check, *addr, new_addr);
414 	skb_clear_hash(skb);
415 	*addr = new_addr;
416 }
417 
418 static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
419 				 __be32 addr[4], const __be32 new_addr[4])
420 {
421 	int transport_len = skb->len - skb_transport_offset(skb);
422 
423 	if (l4_proto == NEXTHDR_TCP) {
424 		if (likely(transport_len >= sizeof(struct tcphdr)))
425 			inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
426 						  addr, new_addr, true);
427 	} else if (l4_proto == NEXTHDR_UDP) {
428 		if (likely(transport_len >= sizeof(struct udphdr))) {
429 			struct udphdr *uh = udp_hdr(skb);
430 
431 			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
432 				inet_proto_csum_replace16(&uh->check, skb,
433 							  addr, new_addr, true);
434 				if (!uh->check)
435 					uh->check = CSUM_MANGLED_0;
436 			}
437 		}
438 	} else if (l4_proto == NEXTHDR_ICMP) {
439 		if (likely(transport_len >= sizeof(struct icmp6hdr)))
440 			inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
441 						  skb, addr, new_addr, true);
442 	}
443 }
444 
445 static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
446 			   const __be32 mask[4], __be32 masked[4])
447 {
448 	masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
449 	masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
450 	masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
451 	masked[3] = OVS_MASKED(old[3], addr[3], mask[3]);
452 }
453 
454 static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
455 			  __be32 addr[4], const __be32 new_addr[4],
456 			  bool recalculate_csum)
457 {
458 	if (recalculate_csum)
459 		update_ipv6_checksum(skb, l4_proto, addr, new_addr);
460 
461 	skb_clear_hash(skb);
462 	memcpy(addr, new_addr, sizeof(__be32[4]));
463 }
464 
465 static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
466 {
467 	/* Bits 21-24 are always unmasked, so this retains their values. */
468 	OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
469 	OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
470 	OVS_SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask);
471 }
472 
473 static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
474 		       u8 mask)
475 {
476 	new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask);
477 
478 	csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
479 	nh->ttl = new_ttl;
480 }
481 
482 static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
483 		    const struct ovs_key_ipv4 *key,
484 		    const struct ovs_key_ipv4 *mask)
485 {
486 	struct iphdr *nh;
487 	__be32 new_addr;
488 	int err;
489 
490 	err = skb_ensure_writable(skb, skb_network_offset(skb) +
491 				  sizeof(struct iphdr));
492 	if (unlikely(err))
493 		return err;
494 
495 	nh = ip_hdr(skb);
496 
497 	/* Setting an IP addresses is typically only a side effect of
498 	 * matching on them in the current userspace implementation, so it
499 	 * makes sense to check if the value actually changed.
500 	 */
501 	if (mask->ipv4_src) {
502 		new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
503 
504 		if (unlikely(new_addr != nh->saddr)) {
505 			set_ip_addr(skb, nh, &nh->saddr, new_addr);
506 			flow_key->ipv4.addr.src = new_addr;
507 		}
508 	}
509 	if (mask->ipv4_dst) {
510 		new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
511 
512 		if (unlikely(new_addr != nh->daddr)) {
513 			set_ip_addr(skb, nh, &nh->daddr, new_addr);
514 			flow_key->ipv4.addr.dst = new_addr;
515 		}
516 	}
517 	if (mask->ipv4_tos) {
518 		ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
519 		flow_key->ip.tos = nh->tos;
520 	}
521 	if (mask->ipv4_ttl) {
522 		set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
523 		flow_key->ip.ttl = nh->ttl;
524 	}
525 
526 	return 0;
527 }
528 
529 static bool is_ipv6_mask_nonzero(const __be32 addr[4])
530 {
531 	return !!(addr[0] | addr[1] | addr[2] | addr[3]);
532 }
533 
534 static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
535 		    const struct ovs_key_ipv6 *key,
536 		    const struct ovs_key_ipv6 *mask)
537 {
538 	struct ipv6hdr *nh;
539 	int err;
540 
541 	err = skb_ensure_writable(skb, skb_network_offset(skb) +
542 				  sizeof(struct ipv6hdr));
543 	if (unlikely(err))
544 		return err;
545 
546 	nh = ipv6_hdr(skb);
547 
548 	/* Setting an IP addresses is typically only a side effect of
549 	 * matching on them in the current userspace implementation, so it
550 	 * makes sense to check if the value actually changed.
551 	 */
552 	if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
553 		__be32 *saddr = (__be32 *)&nh->saddr;
554 		__be32 masked[4];
555 
556 		mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
557 
558 		if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
559 			set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked,
560 				      true);
561 			memcpy(&flow_key->ipv6.addr.src, masked,
562 			       sizeof(flow_key->ipv6.addr.src));
563 		}
564 	}
565 	if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
566 		unsigned int offset = 0;
567 		int flags = IP6_FH_F_SKIP_RH;
568 		bool recalc_csum = true;
569 		__be32 *daddr = (__be32 *)&nh->daddr;
570 		__be32 masked[4];
571 
572 		mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
573 
574 		if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
575 			if (ipv6_ext_hdr(nh->nexthdr))
576 				recalc_csum = (ipv6_find_hdr(skb, &offset,
577 							     NEXTHDR_ROUTING,
578 							     NULL, &flags)
579 					       != NEXTHDR_ROUTING);
580 
581 			set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked,
582 				      recalc_csum);
583 			memcpy(&flow_key->ipv6.addr.dst, masked,
584 			       sizeof(flow_key->ipv6.addr.dst));
585 		}
586 	}
587 	if (mask->ipv6_tclass) {
588 		ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass);
589 		flow_key->ip.tos = ipv6_get_dsfield(nh);
590 	}
591 	if (mask->ipv6_label) {
592 		set_ipv6_fl(nh, ntohl(key->ipv6_label),
593 			    ntohl(mask->ipv6_label));
594 		flow_key->ipv6.label =
595 		    *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
596 	}
597 	if (mask->ipv6_hlimit) {
598 		OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit,
599 			       mask->ipv6_hlimit);
600 		flow_key->ip.ttl = nh->hop_limit;
601 	}
602 	return 0;
603 }
604 
605 /* Must follow skb_ensure_writable() since that can move the skb data. */
606 static void set_tp_port(struct sk_buff *skb, __be16 *port,
607 			__be16 new_port, __sum16 *check)
608 {
609 	inet_proto_csum_replace2(check, skb, *port, new_port, false);
610 	*port = new_port;
611 }
612 
613 static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
614 		   const struct ovs_key_udp *key,
615 		   const struct ovs_key_udp *mask)
616 {
617 	struct udphdr *uh;
618 	__be16 src, dst;
619 	int err;
620 
621 	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
622 				  sizeof(struct udphdr));
623 	if (unlikely(err))
624 		return err;
625 
626 	uh = udp_hdr(skb);
627 	/* Either of the masks is non-zero, so do not bother checking them. */
628 	src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
629 	dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst);
630 
631 	if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
632 		if (likely(src != uh->source)) {
633 			set_tp_port(skb, &uh->source, src, &uh->check);
634 			flow_key->tp.src = src;
635 		}
636 		if (likely(dst != uh->dest)) {
637 			set_tp_port(skb, &uh->dest, dst, &uh->check);
638 			flow_key->tp.dst = dst;
639 		}
640 
641 		if (unlikely(!uh->check))
642 			uh->check = CSUM_MANGLED_0;
643 	} else {
644 		uh->source = src;
645 		uh->dest = dst;
646 		flow_key->tp.src = src;
647 		flow_key->tp.dst = dst;
648 	}
649 
650 	skb_clear_hash(skb);
651 
652 	return 0;
653 }
654 
655 static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
656 		   const struct ovs_key_tcp *key,
657 		   const struct ovs_key_tcp *mask)
658 {
659 	struct tcphdr *th;
660 	__be16 src, dst;
661 	int err;
662 
663 	err = skb_ensure_writable(skb, skb_transport_offset(skb) +
664 				  sizeof(struct tcphdr));
665 	if (unlikely(err))
666 		return err;
667 
668 	th = tcp_hdr(skb);
669 	src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src);
670 	if (likely(src != th->source)) {
671 		set_tp_port(skb, &th->source, src, &th->check);
672 		flow_key->tp.src = src;
673 	}
674 	dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
675 	if (likely(dst != th->dest)) {
676 		set_tp_port(skb, &th->dest, dst, &th->check);
677 		flow_key->tp.dst = dst;
678 	}
679 	skb_clear_hash(skb);
680 
681 	return 0;
682 }
683 
684 static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
685 		    const struct ovs_key_sctp *key,
686 		    const struct ovs_key_sctp *mask)
687 {
688 	unsigned int sctphoff = skb_transport_offset(skb);
689 	struct sctphdr *sh;
690 	__le32 old_correct_csum, new_csum, old_csum;
691 	int err;
692 
693 	err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
694 	if (unlikely(err))
695 		return err;
696 
697 	sh = sctp_hdr(skb);
698 	old_csum = sh->checksum;
699 	old_correct_csum = sctp_compute_cksum(skb, sctphoff);
700 
701 	sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
702 	sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
703 
704 	new_csum = sctp_compute_cksum(skb, sctphoff);
705 
706 	/* Carry any checksum errors through. */
707 	sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
708 
709 	skb_clear_hash(skb);
710 	flow_key->tp.src = sh->source;
711 	flow_key->tp.dst = sh->dest;
712 
713 	return 0;
714 }
715 
716 static int ovs_vport_output(struct net *net, struct sock *sk, struct sk_buff *skb)
717 {
718 	struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
719 	struct vport *vport = data->vport;
720 
721 	if (skb_cow_head(skb, data->l2_len) < 0) {
722 		kfree_skb(skb);
723 		return -ENOMEM;
724 	}
725 
726 	__skb_dst_copy(skb, data->dst);
727 	*OVS_CB(skb) = data->cb;
728 	skb->inner_protocol = data->inner_protocol;
729 	skb->vlan_tci = data->vlan_tci;
730 	skb->vlan_proto = data->vlan_proto;
731 
732 	/* Reconstruct the MAC header.  */
733 	skb_push(skb, data->l2_len);
734 	memcpy(skb->data, &data->l2_data, data->l2_len);
735 	skb_postpush_rcsum(skb, skb->data, data->l2_len);
736 	skb_reset_mac_header(skb);
737 
738 	if (eth_p_mpls(skb->protocol)) {
739 		skb->inner_network_header = skb->network_header;
740 		skb_set_network_header(skb, data->network_offset);
741 		skb_reset_mac_len(skb);
742 	}
743 
744 	ovs_vport_send(vport, skb, data->mac_proto);
745 	return 0;
746 }
747 
748 static unsigned int
749 ovs_dst_get_mtu(const struct dst_entry *dst)
750 {
751 	return dst->dev->mtu;
752 }
753 
754 static struct dst_ops ovs_dst_ops = {
755 	.family = AF_UNSPEC,
756 	.mtu = ovs_dst_get_mtu,
757 };
758 
759 /* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
760  * ovs_vport_output(), which is called once per fragmented packet.
761  */
762 static void prepare_frag(struct vport *vport, struct sk_buff *skb,
763 			 u16 orig_network_offset, u8 mac_proto)
764 {
765 	unsigned int hlen = skb_network_offset(skb);
766 	struct ovs_frag_data *data;
767 
768 	data = this_cpu_ptr(&ovs_frag_data_storage);
769 	data->dst = skb->_skb_refdst;
770 	data->vport = vport;
771 	data->cb = *OVS_CB(skb);
772 	data->inner_protocol = skb->inner_protocol;
773 	data->network_offset = orig_network_offset;
774 	data->vlan_tci = skb->vlan_tci;
775 	data->vlan_proto = skb->vlan_proto;
776 	data->mac_proto = mac_proto;
777 	data->l2_len = hlen;
778 	memcpy(&data->l2_data, skb->data, hlen);
779 
780 	memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
781 	skb_pull(skb, hlen);
782 }
783 
784 static void ovs_fragment(struct net *net, struct vport *vport,
785 			 struct sk_buff *skb, u16 mru,
786 			 struct sw_flow_key *key)
787 {
788 	u16 orig_network_offset = 0;
789 
790 	if (eth_p_mpls(skb->protocol)) {
791 		orig_network_offset = skb_network_offset(skb);
792 		skb->network_header = skb->inner_network_header;
793 	}
794 
795 	if (skb_network_offset(skb) > MAX_L2_LEN) {
796 		OVS_NLERR(1, "L2 header too long to fragment");
797 		goto err;
798 	}
799 
800 	if (key->eth.type == htons(ETH_P_IP)) {
801 		struct dst_entry ovs_dst;
802 		unsigned long orig_dst;
803 
804 		prepare_frag(vport, skb, orig_network_offset,
805 			     ovs_key_mac_proto(key));
806 		dst_init(&ovs_dst, &ovs_dst_ops, NULL, 1,
807 			 DST_OBSOLETE_NONE, DST_NOCOUNT);
808 		ovs_dst.dev = vport->dev;
809 
810 		orig_dst = skb->_skb_refdst;
811 		skb_dst_set_noref(skb, &ovs_dst);
812 		IPCB(skb)->frag_max_size = mru;
813 
814 		ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
815 		refdst_drop(orig_dst);
816 	} else if (key->eth.type == htons(ETH_P_IPV6)) {
817 		const struct nf_ipv6_ops *v6ops = nf_get_ipv6_ops();
818 		unsigned long orig_dst;
819 		struct rt6_info ovs_rt;
820 
821 		if (!v6ops)
822 			goto err;
823 
824 		prepare_frag(vport, skb, orig_network_offset,
825 			     ovs_key_mac_proto(key));
826 		memset(&ovs_rt, 0, sizeof(ovs_rt));
827 		dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
828 			 DST_OBSOLETE_NONE, DST_NOCOUNT);
829 		ovs_rt.dst.dev = vport->dev;
830 
831 		orig_dst = skb->_skb_refdst;
832 		skb_dst_set_noref(skb, &ovs_rt.dst);
833 		IP6CB(skb)->frag_max_size = mru;
834 
835 		v6ops->fragment(net, skb->sk, skb, ovs_vport_output);
836 		refdst_drop(orig_dst);
837 	} else {
838 		WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
839 			  ovs_vport_name(vport), ntohs(key->eth.type), mru,
840 			  vport->dev->mtu);
841 		goto err;
842 	}
843 
844 	return;
845 err:
846 	kfree_skb(skb);
847 }
848 
849 static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
850 		      struct sw_flow_key *key)
851 {
852 	struct vport *vport = ovs_vport_rcu(dp, out_port);
853 
854 	if (likely(vport)) {
855 		u16 mru = OVS_CB(skb)->mru;
856 		u32 cutlen = OVS_CB(skb)->cutlen;
857 
858 		if (unlikely(cutlen > 0)) {
859 			if (skb->len - cutlen > ovs_mac_header_len(key))
860 				pskb_trim(skb, skb->len - cutlen);
861 			else
862 				pskb_trim(skb, ovs_mac_header_len(key));
863 		}
864 
865 		if (likely(!mru ||
866 		           (skb->len <= mru + vport->dev->hard_header_len))) {
867 			ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
868 		} else if (mru <= vport->dev->mtu) {
869 			struct net *net = read_pnet(&dp->net);
870 
871 			ovs_fragment(net, vport, skb, mru, key);
872 		} else {
873 			kfree_skb(skb);
874 		}
875 	} else {
876 		kfree_skb(skb);
877 	}
878 }
879 
880 static int output_userspace(struct datapath *dp, struct sk_buff *skb,
881 			    struct sw_flow_key *key, const struct nlattr *attr,
882 			    const struct nlattr *actions, int actions_len,
883 			    uint32_t cutlen)
884 {
885 	struct dp_upcall_info upcall;
886 	const struct nlattr *a;
887 	int rem;
888 
889 	memset(&upcall, 0, sizeof(upcall));
890 	upcall.cmd = OVS_PACKET_CMD_ACTION;
891 	upcall.mru = OVS_CB(skb)->mru;
892 
893 	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
894 		 a = nla_next(a, &rem)) {
895 		switch (nla_type(a)) {
896 		case OVS_USERSPACE_ATTR_USERDATA:
897 			upcall.userdata = a;
898 			break;
899 
900 		case OVS_USERSPACE_ATTR_PID:
901 			upcall.portid = nla_get_u32(a);
902 			break;
903 
904 		case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
905 			/* Get out tunnel info. */
906 			struct vport *vport;
907 
908 			vport = ovs_vport_rcu(dp, nla_get_u32(a));
909 			if (vport) {
910 				int err;
911 
912 				err = dev_fill_metadata_dst(vport->dev, skb);
913 				if (!err)
914 					upcall.egress_tun_info = skb_tunnel_info(skb);
915 			}
916 
917 			break;
918 		}
919 
920 		case OVS_USERSPACE_ATTR_ACTIONS: {
921 			/* Include actions. */
922 			upcall.actions = actions;
923 			upcall.actions_len = actions_len;
924 			break;
925 		}
926 
927 		} /* End of switch. */
928 	}
929 
930 	return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
931 }
932 
933 /* When 'last' is true, sample() should always consume the 'skb'.
934  * Otherwise, sample() should keep 'skb' intact regardless what
935  * actions are executed within sample().
936  */
937 static int sample(struct datapath *dp, struct sk_buff *skb,
938 		  struct sw_flow_key *key, const struct nlattr *attr,
939 		  bool last)
940 {
941 	struct nlattr *actions;
942 	struct nlattr *sample_arg;
943 	int rem = nla_len(attr);
944 	const struct sample_arg *arg;
945 	bool clone_flow_key;
946 
947 	/* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
948 	sample_arg = nla_data(attr);
949 	arg = nla_data(sample_arg);
950 	actions = nla_next(sample_arg, &rem);
951 
952 	if ((arg->probability != U32_MAX) &&
953 	    (!arg->probability || prandom_u32() > arg->probability)) {
954 		if (last)
955 			consume_skb(skb);
956 		return 0;
957 	}
958 
959 	clone_flow_key = !arg->exec;
960 	return clone_execute(dp, skb, key, 0, actions, rem, last,
961 			     clone_flow_key);
962 }
963 
964 static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
965 			 const struct nlattr *attr)
966 {
967 	struct ovs_action_hash *hash_act = nla_data(attr);
968 	u32 hash = 0;
969 
970 	/* OVS_HASH_ALG_L4 is the only possible hash algorithm.  */
971 	hash = skb_get_hash(skb);
972 	hash = jhash_1word(hash, hash_act->hash_basis);
973 	if (!hash)
974 		hash = 0x1;
975 
976 	key->ovs_flow_hash = hash;
977 }
978 
979 static int execute_set_action(struct sk_buff *skb,
980 			      struct sw_flow_key *flow_key,
981 			      const struct nlattr *a)
982 {
983 	/* Only tunnel set execution is supported without a mask. */
984 	if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
985 		struct ovs_tunnel_info *tun = nla_data(a);
986 
987 		skb_dst_drop(skb);
988 		dst_hold((struct dst_entry *)tun->tun_dst);
989 		skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
990 		return 0;
991 	}
992 
993 	return -EINVAL;
994 }
995 
996 /* Mask is at the midpoint of the data. */
997 #define get_mask(a, type) ((const type)nla_data(a) + 1)
998 
999 static int execute_masked_set_action(struct sk_buff *skb,
1000 				     struct sw_flow_key *flow_key,
1001 				     const struct nlattr *a)
1002 {
1003 	int err = 0;
1004 
1005 	switch (nla_type(a)) {
1006 	case OVS_KEY_ATTR_PRIORITY:
1007 		OVS_SET_MASKED(skb->priority, nla_get_u32(a),
1008 			       *get_mask(a, u32 *));
1009 		flow_key->phy.priority = skb->priority;
1010 		break;
1011 
1012 	case OVS_KEY_ATTR_SKB_MARK:
1013 		OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
1014 		flow_key->phy.skb_mark = skb->mark;
1015 		break;
1016 
1017 	case OVS_KEY_ATTR_TUNNEL_INFO:
1018 		/* Masked data not supported for tunnel. */
1019 		err = -EINVAL;
1020 		break;
1021 
1022 	case OVS_KEY_ATTR_ETHERNET:
1023 		err = set_eth_addr(skb, flow_key, nla_data(a),
1024 				   get_mask(a, struct ovs_key_ethernet *));
1025 		break;
1026 
1027 	case OVS_KEY_ATTR_IPV4:
1028 		err = set_ipv4(skb, flow_key, nla_data(a),
1029 			       get_mask(a, struct ovs_key_ipv4 *));
1030 		break;
1031 
1032 	case OVS_KEY_ATTR_IPV6:
1033 		err = set_ipv6(skb, flow_key, nla_data(a),
1034 			       get_mask(a, struct ovs_key_ipv6 *));
1035 		break;
1036 
1037 	case OVS_KEY_ATTR_TCP:
1038 		err = set_tcp(skb, flow_key, nla_data(a),
1039 			      get_mask(a, struct ovs_key_tcp *));
1040 		break;
1041 
1042 	case OVS_KEY_ATTR_UDP:
1043 		err = set_udp(skb, flow_key, nla_data(a),
1044 			      get_mask(a, struct ovs_key_udp *));
1045 		break;
1046 
1047 	case OVS_KEY_ATTR_SCTP:
1048 		err = set_sctp(skb, flow_key, nla_data(a),
1049 			       get_mask(a, struct ovs_key_sctp *));
1050 		break;
1051 
1052 	case OVS_KEY_ATTR_MPLS:
1053 		err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
1054 								    __be32 *));
1055 		break;
1056 
1057 	case OVS_KEY_ATTR_CT_STATE:
1058 	case OVS_KEY_ATTR_CT_ZONE:
1059 	case OVS_KEY_ATTR_CT_MARK:
1060 	case OVS_KEY_ATTR_CT_LABELS:
1061 	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
1062 	case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
1063 		err = -EINVAL;
1064 		break;
1065 	}
1066 
1067 	return err;
1068 }
1069 
1070 static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
1071 			  struct sw_flow_key *key,
1072 			  const struct nlattr *a, bool last)
1073 {
1074 	u32 recirc_id;
1075 
1076 	if (!is_flow_key_valid(key)) {
1077 		int err;
1078 
1079 		err = ovs_flow_key_update(skb, key);
1080 		if (err)
1081 			return err;
1082 	}
1083 	BUG_ON(!is_flow_key_valid(key));
1084 
1085 	recirc_id = nla_get_u32(a);
1086 	return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true);
1087 }
1088 
1089 /* Execute a list of actions against 'skb'. */
1090 static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
1091 			      struct sw_flow_key *key,
1092 			      const struct nlattr *attr, int len)
1093 {
1094 	const struct nlattr *a;
1095 	int rem;
1096 
1097 	for (a = attr, rem = len; rem > 0;
1098 	     a = nla_next(a, &rem)) {
1099 		int err = 0;
1100 
1101 		switch (nla_type(a)) {
1102 		case OVS_ACTION_ATTR_OUTPUT: {
1103 			int port = nla_get_u32(a);
1104 			struct sk_buff *clone;
1105 
1106 			/* Every output action needs a separate clone
1107 			 * of 'skb', In case the output action is the
1108 			 * last action, cloning can be avoided.
1109 			 */
1110 			if (nla_is_last(a, rem)) {
1111 				do_output(dp, skb, port, key);
1112 				/* 'skb' has been used for output.
1113 				 */
1114 				return 0;
1115 			}
1116 
1117 			clone = skb_clone(skb, GFP_ATOMIC);
1118 			if (clone)
1119 				do_output(dp, clone, port, key);
1120 			OVS_CB(skb)->cutlen = 0;
1121 			break;
1122 		}
1123 
1124 		case OVS_ACTION_ATTR_TRUNC: {
1125 			struct ovs_action_trunc *trunc = nla_data(a);
1126 
1127 			if (skb->len > trunc->max_len)
1128 				OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
1129 			break;
1130 		}
1131 
1132 		case OVS_ACTION_ATTR_USERSPACE:
1133 			output_userspace(dp, skb, key, a, attr,
1134 						     len, OVS_CB(skb)->cutlen);
1135 			OVS_CB(skb)->cutlen = 0;
1136 			break;
1137 
1138 		case OVS_ACTION_ATTR_HASH:
1139 			execute_hash(skb, key, a);
1140 			break;
1141 
1142 		case OVS_ACTION_ATTR_PUSH_MPLS:
1143 			err = push_mpls(skb, key, nla_data(a));
1144 			break;
1145 
1146 		case OVS_ACTION_ATTR_POP_MPLS:
1147 			err = pop_mpls(skb, key, nla_get_be16(a));
1148 			break;
1149 
1150 		case OVS_ACTION_ATTR_PUSH_VLAN:
1151 			err = push_vlan(skb, key, nla_data(a));
1152 			break;
1153 
1154 		case OVS_ACTION_ATTR_POP_VLAN:
1155 			err = pop_vlan(skb, key);
1156 			break;
1157 
1158 		case OVS_ACTION_ATTR_RECIRC: {
1159 			bool last = nla_is_last(a, rem);
1160 
1161 			err = execute_recirc(dp, skb, key, a, last);
1162 			if (last) {
1163 				/* If this is the last action, the skb has
1164 				 * been consumed or freed.
1165 				 * Return immediately.
1166 				 */
1167 				return err;
1168 			}
1169 			break;
1170 		}
1171 
1172 		case OVS_ACTION_ATTR_SET:
1173 			err = execute_set_action(skb, key, nla_data(a));
1174 			break;
1175 
1176 		case OVS_ACTION_ATTR_SET_MASKED:
1177 		case OVS_ACTION_ATTR_SET_TO_MASKED:
1178 			err = execute_masked_set_action(skb, key, nla_data(a));
1179 			break;
1180 
1181 		case OVS_ACTION_ATTR_SAMPLE: {
1182 			bool last = nla_is_last(a, rem);
1183 
1184 			err = sample(dp, skb, key, a, last);
1185 			if (last)
1186 				return err;
1187 
1188 			break;
1189 		}
1190 
1191 		case OVS_ACTION_ATTR_CT:
1192 			if (!is_flow_key_valid(key)) {
1193 				err = ovs_flow_key_update(skb, key);
1194 				if (err)
1195 					return err;
1196 			}
1197 
1198 			err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
1199 					     nla_data(a));
1200 
1201 			/* Hide stolen IP fragments from user space. */
1202 			if (err)
1203 				return err == -EINPROGRESS ? 0 : err;
1204 			break;
1205 
1206 		case OVS_ACTION_ATTR_PUSH_ETH:
1207 			err = push_eth(skb, key, nla_data(a));
1208 			break;
1209 
1210 		case OVS_ACTION_ATTR_POP_ETH:
1211 			err = pop_eth(skb, key);
1212 			break;
1213 		}
1214 
1215 		if (unlikely(err)) {
1216 			kfree_skb(skb);
1217 			return err;
1218 		}
1219 	}
1220 
1221 	consume_skb(skb);
1222 	return 0;
1223 }
1224 
1225 /* Execute the actions on the clone of the packet. The effect of the
1226  * execution does not affect the original 'skb' nor the original 'key'.
1227  *
1228  * The execution may be deferred in case the actions can not be executed
1229  * immediately.
1230  */
1231 static int clone_execute(struct datapath *dp, struct sk_buff *skb,
1232 			 struct sw_flow_key *key, u32 recirc_id,
1233 			 const struct nlattr *actions, int len,
1234 			 bool last, bool clone_flow_key)
1235 {
1236 	struct deferred_action *da;
1237 	struct sw_flow_key *clone;
1238 
1239 	skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
1240 	if (!skb) {
1241 		/* Out of memory, skip this action.
1242 		 */
1243 		return 0;
1244 	}
1245 
1246 	/* When clone_flow_key is false, the 'key' will not be change
1247 	 * by the actions, then the 'key' can be used directly.
1248 	 * Otherwise, try to clone key from the next recursion level of
1249 	 * 'flow_keys'. If clone is successful, execute the actions
1250 	 * without deferring.
1251 	 */
1252 	clone = clone_flow_key ? clone_key(key) : key;
1253 	if (clone) {
1254 		int err = 0;
1255 
1256 		if (actions) { /* Sample action */
1257 			if (clone_flow_key)
1258 				__this_cpu_inc(exec_actions_level);
1259 
1260 			err = do_execute_actions(dp, skb, clone,
1261 						 actions, len);
1262 
1263 			if (clone_flow_key)
1264 				__this_cpu_dec(exec_actions_level);
1265 		} else { /* Recirc action */
1266 			clone->recirc_id = recirc_id;
1267 			ovs_dp_process_packet(skb, clone);
1268 		}
1269 		return err;
1270 	}
1271 
1272 	/* Out of 'flow_keys' space. Defer actions */
1273 	da = add_deferred_actions(skb, key, actions, len);
1274 	if (da) {
1275 		if (!actions) { /* Recirc action */
1276 			key = &da->pkt_key;
1277 			key->recirc_id = recirc_id;
1278 		}
1279 	} else {
1280 		/* Out of per CPU action FIFO space. Drop the 'skb' and
1281 		 * log an error.
1282 		 */
1283 		kfree_skb(skb);
1284 
1285 		if (net_ratelimit()) {
1286 			if (actions) { /* Sample action */
1287 				pr_warn("%s: deferred action limit reached, drop sample action\n",
1288 					ovs_dp_name(dp));
1289 			} else {  /* Recirc action */
1290 				pr_warn("%s: deferred action limit reached, drop recirc action\n",
1291 					ovs_dp_name(dp));
1292 			}
1293 		}
1294 	}
1295 	return 0;
1296 }
1297 
1298 static void process_deferred_actions(struct datapath *dp)
1299 {
1300 	struct action_fifo *fifo = this_cpu_ptr(action_fifos);
1301 
1302 	/* Do not touch the FIFO in case there is no deferred actions. */
1303 	if (action_fifo_is_empty(fifo))
1304 		return;
1305 
1306 	/* Finishing executing all deferred actions. */
1307 	do {
1308 		struct deferred_action *da = action_fifo_get(fifo);
1309 		struct sk_buff *skb = da->skb;
1310 		struct sw_flow_key *key = &da->pkt_key;
1311 		const struct nlattr *actions = da->actions;
1312 		int actions_len = da->actions_len;
1313 
1314 		if (actions)
1315 			do_execute_actions(dp, skb, key, actions, actions_len);
1316 		else
1317 			ovs_dp_process_packet(skb, key);
1318 	} while (!action_fifo_is_empty(fifo));
1319 
1320 	/* Reset FIFO for the next packet.  */
1321 	action_fifo_init(fifo);
1322 }
1323 
1324 /* Execute a list of actions against 'skb'. */
1325 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
1326 			const struct sw_flow_actions *acts,
1327 			struct sw_flow_key *key)
1328 {
1329 	int err, level;
1330 
1331 	level = __this_cpu_inc_return(exec_actions_level);
1332 	if (unlikely(level > OVS_RECURSION_LIMIT)) {
1333 		net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
1334 				     ovs_dp_name(dp));
1335 		kfree_skb(skb);
1336 		err = -ENETDOWN;
1337 		goto out;
1338 	}
1339 
1340 	OVS_CB(skb)->acts_origlen = acts->orig_len;
1341 	err = do_execute_actions(dp, skb, key,
1342 				 acts->actions, acts->actions_len);
1343 
1344 	if (level == 1)
1345 		process_deferred_actions(dp);
1346 
1347 out:
1348 	__this_cpu_dec(exec_actions_level);
1349 	return err;
1350 }
1351 
1352 int action_fifos_init(void)
1353 {
1354 	action_fifos = alloc_percpu(struct action_fifo);
1355 	if (!action_fifos)
1356 		return -ENOMEM;
1357 
1358 	flow_keys = alloc_percpu(struct action_flow_keys);
1359 	if (!flow_keys) {
1360 		free_percpu(action_fifos);
1361 		return -ENOMEM;
1362 	}
1363 
1364 	return 0;
1365 }
1366 
1367 void action_fifos_exit(void)
1368 {
1369 	free_percpu(action_fifos);
1370 	free_percpu(flow_keys);
1371 }
1372