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/skbuff.h> 22#include <linux/in.h> 23#include <linux/ip.h> 24#include <linux/openvswitch.h> 25#include <linux/sctp.h> 26#include <linux/tcp.h> 27#include <linux/udp.h> 28#include <linux/in6.h> 29#include <linux/if_arp.h> 30#include <linux/if_vlan.h> 31#include <net/ip.h> 32#include <net/ipv6.h> 33#include <net/checksum.h> 34#include <net/dsfield.h> 35#include <net/sctp/checksum.h> 36 37#include "datapath.h" 38#include "flow.h" 39#include "vport.h" 40 41static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 42 struct sw_flow_key *key, 43 const struct nlattr *attr, int len); 44 45struct deferred_action { 46 struct sk_buff *skb; 47 const struct nlattr *actions; 48 49 /* Store pkt_key clone when creating deferred action. */ 50 struct sw_flow_key pkt_key; 51}; 52 53#define DEFERRED_ACTION_FIFO_SIZE 10 54struct action_fifo { 55 int head; 56 int tail; 57 /* Deferred action fifo queue storage. */ 58 struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE]; 59}; 60 61static struct action_fifo __percpu *action_fifos; 62static DEFINE_PER_CPU(int, exec_actions_level); 63 64static void action_fifo_init(struct action_fifo *fifo) 65{ 66 fifo->head = 0; 67 fifo->tail = 0; 68} 69 70static bool action_fifo_is_empty(struct action_fifo *fifo) 71{ 72 return (fifo->head == fifo->tail); 73} 74 75static struct deferred_action *action_fifo_get(struct action_fifo *fifo) 76{ 77 if (action_fifo_is_empty(fifo)) 78 return NULL; 79 80 return &fifo->fifo[fifo->tail++]; 81} 82 83static struct deferred_action *action_fifo_put(struct action_fifo *fifo) 84{ 85 if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1) 86 return NULL; 87 88 return &fifo->fifo[fifo->head++]; 89} 90 91/* Return true if fifo is not full */ 92static struct deferred_action *add_deferred_actions(struct sk_buff *skb, 93 struct sw_flow_key *key, 94 const struct nlattr *attr) 95{ 96 struct action_fifo *fifo; 97 struct deferred_action *da; 98 99 fifo = this_cpu_ptr(action_fifos); 100 da = action_fifo_put(fifo); 101 if (da) { 102 da->skb = skb; 103 da->actions = attr; 104 da->pkt_key = *key; 105 } 106 107 return da; 108} 109 110static int make_writable(struct sk_buff *skb, int write_len) 111{ 112 if (!pskb_may_pull(skb, write_len)) 113 return -ENOMEM; 114 115 if (!skb_cloned(skb) || skb_clone_writable(skb, write_len)) 116 return 0; 117 118 return pskb_expand_head(skb, 0, 0, GFP_ATOMIC); 119} 120 121/* remove VLAN header from packet and update csum accordingly. */ 122static int __pop_vlan_tci(struct sk_buff *skb, __be16 *current_tci) 123{ 124 struct vlan_hdr *vhdr; 125 int err; 126 127 err = make_writable(skb, VLAN_ETH_HLEN); 128 if (unlikely(err)) 129 return err; 130 131 if (skb->ip_summed == CHECKSUM_COMPLETE) 132 skb->csum = csum_sub(skb->csum, csum_partial(skb->data 133 + (2 * ETH_ALEN), VLAN_HLEN, 0)); 134 135 vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN); 136 *current_tci = vhdr->h_vlan_TCI; 137 138 memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN); 139 __skb_pull(skb, VLAN_HLEN); 140 141 vlan_set_encap_proto(skb, vhdr); 142 skb->mac_header += VLAN_HLEN; 143 if (skb_network_offset(skb) < ETH_HLEN) 144 skb_set_network_header(skb, ETH_HLEN); 145 skb_reset_mac_len(skb); 146 147 return 0; 148} 149 150static int pop_vlan(struct sk_buff *skb) 151{ 152 __be16 tci; 153 int err; 154 155 if (likely(vlan_tx_tag_present(skb))) { 156 skb->vlan_tci = 0; 157 } else { 158 if (unlikely(skb->protocol != htons(ETH_P_8021Q) || 159 skb->len < VLAN_ETH_HLEN)) 160 return 0; 161 162 err = __pop_vlan_tci(skb, &tci); 163 if (err) 164 return err; 165 } 166 /* move next vlan tag to hw accel tag */ 167 if (likely(skb->protocol != htons(ETH_P_8021Q) || 168 skb->len < VLAN_ETH_HLEN)) 169 return 0; 170 171 err = __pop_vlan_tci(skb, &tci); 172 if (unlikely(err)) 173 return err; 174 175 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), ntohs(tci)); 176 return 0; 177} 178 179static int push_vlan(struct sk_buff *skb, const struct ovs_action_push_vlan *vlan) 180{ 181 if (unlikely(vlan_tx_tag_present(skb))) { 182 u16 current_tag; 183 184 /* push down current VLAN tag */ 185 current_tag = vlan_tx_tag_get(skb); 186 187 if (!__vlan_put_tag(skb, skb->vlan_proto, current_tag)) 188 return -ENOMEM; 189 190 if (skb->ip_summed == CHECKSUM_COMPLETE) 191 skb->csum = csum_add(skb->csum, csum_partial(skb->data 192 + (2 * ETH_ALEN), VLAN_HLEN, 0)); 193 194 } 195 __vlan_hwaccel_put_tag(skb, vlan->vlan_tpid, ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT); 196 return 0; 197} 198 199static int set_eth_addr(struct sk_buff *skb, 200 const struct ovs_key_ethernet *eth_key) 201{ 202 int err; 203 err = make_writable(skb, ETH_HLEN); 204 if (unlikely(err)) 205 return err; 206 207 skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 208 209 ether_addr_copy(eth_hdr(skb)->h_source, eth_key->eth_src); 210 ether_addr_copy(eth_hdr(skb)->h_dest, eth_key->eth_dst); 211 212 ovs_skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); 213 214 return 0; 215} 216 217static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh, 218 __be32 *addr, __be32 new_addr) 219{ 220 int transport_len = skb->len - skb_transport_offset(skb); 221 222 if (nh->protocol == IPPROTO_TCP) { 223 if (likely(transport_len >= sizeof(struct tcphdr))) 224 inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb, 225 *addr, new_addr, 1); 226 } else if (nh->protocol == IPPROTO_UDP) { 227 if (likely(transport_len >= sizeof(struct udphdr))) { 228 struct udphdr *uh = udp_hdr(skb); 229 230 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 231 inet_proto_csum_replace4(&uh->check, skb, 232 *addr, new_addr, 1); 233 if (!uh->check) 234 uh->check = CSUM_MANGLED_0; 235 } 236 } 237 } 238 239 csum_replace4(&nh->check, *addr, new_addr); 240 skb_clear_hash(skb); 241 *addr = new_addr; 242} 243 244static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto, 245 __be32 addr[4], const __be32 new_addr[4]) 246{ 247 int transport_len = skb->len - skb_transport_offset(skb); 248 249 if (l4_proto == NEXTHDR_TCP) { 250 if (likely(transport_len >= sizeof(struct tcphdr))) 251 inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb, 252 addr, new_addr, 1); 253 } else if (l4_proto == NEXTHDR_UDP) { 254 if (likely(transport_len >= sizeof(struct udphdr))) { 255 struct udphdr *uh = udp_hdr(skb); 256 257 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { 258 inet_proto_csum_replace16(&uh->check, skb, 259 addr, new_addr, 1); 260 if (!uh->check) 261 uh->check = CSUM_MANGLED_0; 262 } 263 } 264 } else if (l4_proto == NEXTHDR_ICMP) { 265 if (likely(transport_len >= sizeof(struct icmp6hdr))) 266 inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum, 267 skb, addr, new_addr, 1); 268 } 269} 270 271static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto, 272 __be32 addr[4], const __be32 new_addr[4], 273 bool recalculate_csum) 274{ 275 if (recalculate_csum) 276 update_ipv6_checksum(skb, l4_proto, addr, new_addr); 277 278 skb_clear_hash(skb); 279 memcpy(addr, new_addr, sizeof(__be32[4])); 280} 281 282static void set_ipv6_tc(struct ipv6hdr *nh, u8 tc) 283{ 284 nh->priority = tc >> 4; 285 nh->flow_lbl[0] = (nh->flow_lbl[0] & 0x0F) | ((tc & 0x0F) << 4); 286} 287 288static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl) 289{ 290 nh->flow_lbl[0] = (nh->flow_lbl[0] & 0xF0) | (fl & 0x000F0000) >> 16; 291 nh->flow_lbl[1] = (fl & 0x0000FF00) >> 8; 292 nh->flow_lbl[2] = fl & 0x000000FF; 293} 294 295static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl) 296{ 297 csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8)); 298 nh->ttl = new_ttl; 299} 300 301static int set_ipv4(struct sk_buff *skb, const struct ovs_key_ipv4 *ipv4_key) 302{ 303 struct iphdr *nh; 304 int err; 305 306 err = make_writable(skb, skb_network_offset(skb) + 307 sizeof(struct iphdr)); 308 if (unlikely(err)) 309 return err; 310 311 nh = ip_hdr(skb); 312 313 if (ipv4_key->ipv4_src != nh->saddr) 314 set_ip_addr(skb, nh, &nh->saddr, ipv4_key->ipv4_src); 315 316 if (ipv4_key->ipv4_dst != nh->daddr) 317 set_ip_addr(skb, nh, &nh->daddr, ipv4_key->ipv4_dst); 318 319 if (ipv4_key->ipv4_tos != nh->tos) 320 ipv4_change_dsfield(nh, 0, ipv4_key->ipv4_tos); 321 322 if (ipv4_key->ipv4_ttl != nh->ttl) 323 set_ip_ttl(skb, nh, ipv4_key->ipv4_ttl); 324 325 return 0; 326} 327 328static int set_ipv6(struct sk_buff *skb, const struct ovs_key_ipv6 *ipv6_key) 329{ 330 struct ipv6hdr *nh; 331 int err; 332 __be32 *saddr; 333 __be32 *daddr; 334 335 err = make_writable(skb, skb_network_offset(skb) + 336 sizeof(struct ipv6hdr)); 337 if (unlikely(err)) 338 return err; 339 340 nh = ipv6_hdr(skb); 341 saddr = (__be32 *)&nh->saddr; 342 daddr = (__be32 *)&nh->daddr; 343 344 if (memcmp(ipv6_key->ipv6_src, saddr, sizeof(ipv6_key->ipv6_src))) 345 set_ipv6_addr(skb, ipv6_key->ipv6_proto, saddr, 346 ipv6_key->ipv6_src, true); 347 348 if (memcmp(ipv6_key->ipv6_dst, daddr, sizeof(ipv6_key->ipv6_dst))) { 349 unsigned int offset = 0; 350 int flags = IP6_FH_F_SKIP_RH; 351 bool recalc_csum = true; 352 353 if (ipv6_ext_hdr(nh->nexthdr)) 354 recalc_csum = ipv6_find_hdr(skb, &offset, 355 NEXTHDR_ROUTING, NULL, 356 &flags) != NEXTHDR_ROUTING; 357 358 set_ipv6_addr(skb, ipv6_key->ipv6_proto, daddr, 359 ipv6_key->ipv6_dst, recalc_csum); 360 } 361 362 set_ipv6_tc(nh, ipv6_key->ipv6_tclass); 363 set_ipv6_fl(nh, ntohl(ipv6_key->ipv6_label)); 364 nh->hop_limit = ipv6_key->ipv6_hlimit; 365 366 return 0; 367} 368 369/* Must follow make_writable() since that can move the skb data. */ 370static void set_tp_port(struct sk_buff *skb, __be16 *port, 371 __be16 new_port, __sum16 *check) 372{ 373 inet_proto_csum_replace2(check, skb, *port, new_port, 0); 374 *port = new_port; 375 skb_clear_hash(skb); 376} 377 378static void set_udp_port(struct sk_buff *skb, __be16 *port, __be16 new_port) 379{ 380 struct udphdr *uh = udp_hdr(skb); 381 382 if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) { 383 set_tp_port(skb, port, new_port, &uh->check); 384 385 if (!uh->check) 386 uh->check = CSUM_MANGLED_0; 387 } else { 388 *port = new_port; 389 skb_clear_hash(skb); 390 } 391} 392 393static int set_udp(struct sk_buff *skb, const struct ovs_key_udp *udp_port_key) 394{ 395 struct udphdr *uh; 396 int err; 397 398 err = make_writable(skb, skb_transport_offset(skb) + 399 sizeof(struct udphdr)); 400 if (unlikely(err)) 401 return err; 402 403 uh = udp_hdr(skb); 404 if (udp_port_key->udp_src != uh->source) 405 set_udp_port(skb, &uh->source, udp_port_key->udp_src); 406 407 if (udp_port_key->udp_dst != uh->dest) 408 set_udp_port(skb, &uh->dest, udp_port_key->udp_dst); 409 410 return 0; 411} 412 413static int set_tcp(struct sk_buff *skb, const struct ovs_key_tcp *tcp_port_key) 414{ 415 struct tcphdr *th; 416 int err; 417 418 err = make_writable(skb, skb_transport_offset(skb) + 419 sizeof(struct tcphdr)); 420 if (unlikely(err)) 421 return err; 422 423 th = tcp_hdr(skb); 424 if (tcp_port_key->tcp_src != th->source) 425 set_tp_port(skb, &th->source, tcp_port_key->tcp_src, &th->check); 426 427 if (tcp_port_key->tcp_dst != th->dest) 428 set_tp_port(skb, &th->dest, tcp_port_key->tcp_dst, &th->check); 429 430 return 0; 431} 432 433static int set_sctp(struct sk_buff *skb, 434 const struct ovs_key_sctp *sctp_port_key) 435{ 436 struct sctphdr *sh; 437 int err; 438 unsigned int sctphoff = skb_transport_offset(skb); 439 440 err = make_writable(skb, sctphoff + sizeof(struct sctphdr)); 441 if (unlikely(err)) 442 return err; 443 444 sh = sctp_hdr(skb); 445 if (sctp_port_key->sctp_src != sh->source || 446 sctp_port_key->sctp_dst != sh->dest) { 447 __le32 old_correct_csum, new_csum, old_csum; 448 449 old_csum = sh->checksum; 450 old_correct_csum = sctp_compute_cksum(skb, sctphoff); 451 452 sh->source = sctp_port_key->sctp_src; 453 sh->dest = sctp_port_key->sctp_dst; 454 455 new_csum = sctp_compute_cksum(skb, sctphoff); 456 457 /* Carry any checksum errors through. */ 458 sh->checksum = old_csum ^ old_correct_csum ^ new_csum; 459 460 skb_clear_hash(skb); 461 } 462 463 return 0; 464} 465 466static int do_output(struct datapath *dp, struct sk_buff *skb, int out_port) 467{ 468 struct vport *vport; 469 470 if (unlikely(!skb)) 471 return -ENOMEM; 472 473 vport = ovs_vport_rcu(dp, out_port); 474 if (unlikely(!vport)) { 475 kfree_skb(skb); 476 return -ENODEV; 477 } 478 479 ovs_vport_send(vport, skb); 480 return 0; 481} 482 483static int output_userspace(struct datapath *dp, struct sk_buff *skb, 484 struct sw_flow_key *key, const struct nlattr *attr) 485{ 486 struct dp_upcall_info upcall; 487 const struct nlattr *a; 488 int rem; 489 490 upcall.cmd = OVS_PACKET_CMD_ACTION; 491 upcall.key = key; 492 upcall.userdata = NULL; 493 upcall.portid = 0; 494 495 for (a = nla_data(attr), rem = nla_len(attr); rem > 0; 496 a = nla_next(a, &rem)) { 497 switch (nla_type(a)) { 498 case OVS_USERSPACE_ATTR_USERDATA: 499 upcall.userdata = a; 500 break; 501 502 case OVS_USERSPACE_ATTR_PID: 503 upcall.portid = nla_get_u32(a); 504 break; 505 } 506 } 507 508 return ovs_dp_upcall(dp, skb, &upcall); 509} 510 511static bool last_action(const struct nlattr *a, int rem) 512{ 513 return a->nla_len == rem; 514} 515 516static int sample(struct datapath *dp, struct sk_buff *skb, 517 struct sw_flow_key *key, const struct nlattr *attr) 518{ 519 const struct nlattr *acts_list = NULL; 520 const struct nlattr *a; 521 int rem; 522 523 for (a = nla_data(attr), rem = nla_len(attr); rem > 0; 524 a = nla_next(a, &rem)) { 525 switch (nla_type(a)) { 526 case OVS_SAMPLE_ATTR_PROBABILITY: 527 if (prandom_u32() >= nla_get_u32(a)) 528 return 0; 529 break; 530 531 case OVS_SAMPLE_ATTR_ACTIONS: 532 acts_list = a; 533 break; 534 } 535 } 536 537 rem = nla_len(acts_list); 538 a = nla_data(acts_list); 539 540 /* Actions list is empty, do nothing */ 541 if (unlikely(!rem)) 542 return 0; 543 544 /* The only known usage of sample action is having a single user-space 545 * action. Treat this usage as a special case. 546 * The output_userspace() should clone the skb to be sent to the 547 * user space. This skb will be consumed by its caller. 548 */ 549 if (likely(nla_type(a) == OVS_ACTION_ATTR_USERSPACE && 550 last_action(a, rem))) 551 return output_userspace(dp, skb, key, a); 552 553 skb = skb_clone(skb, GFP_ATOMIC); 554 if (!skb) 555 /* Skip the sample action when out of memory. */ 556 return 0; 557 558 if (!add_deferred_actions(skb, key, a)) { 559 if (net_ratelimit()) 560 pr_warn("%s: deferred actions limit reached, dropping sample action\n", 561 ovs_dp_name(dp)); 562 563 kfree_skb(skb); 564 } 565 return 0; 566} 567 568static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key, 569 const struct nlattr *attr) 570{ 571 struct ovs_action_hash *hash_act = nla_data(attr); 572 u32 hash = 0; 573 574 /* OVS_HASH_ALG_L4 is the only possible hash algorithm. */ 575 hash = skb_get_hash(skb); 576 hash = jhash_1word(hash, hash_act->hash_basis); 577 if (!hash) 578 hash = 0x1; 579 580 key->ovs_flow_hash = hash; 581} 582 583static int execute_set_action(struct sk_buff *skb, 584 const struct nlattr *nested_attr) 585{ 586 int err = 0; 587 588 switch (nla_type(nested_attr)) { 589 case OVS_KEY_ATTR_PRIORITY: 590 skb->priority = nla_get_u32(nested_attr); 591 break; 592 593 case OVS_KEY_ATTR_SKB_MARK: 594 skb->mark = nla_get_u32(nested_attr); 595 break; 596 597 case OVS_KEY_ATTR_TUNNEL_INFO: 598 OVS_CB(skb)->egress_tun_info = nla_data(nested_attr); 599 break; 600 601 case OVS_KEY_ATTR_ETHERNET: 602 err = set_eth_addr(skb, nla_data(nested_attr)); 603 break; 604 605 case OVS_KEY_ATTR_IPV4: 606 err = set_ipv4(skb, nla_data(nested_attr)); 607 break; 608 609 case OVS_KEY_ATTR_IPV6: 610 err = set_ipv6(skb, nla_data(nested_attr)); 611 break; 612 613 case OVS_KEY_ATTR_TCP: 614 err = set_tcp(skb, nla_data(nested_attr)); 615 break; 616 617 case OVS_KEY_ATTR_UDP: 618 err = set_udp(skb, nla_data(nested_attr)); 619 break; 620 621 case OVS_KEY_ATTR_SCTP: 622 err = set_sctp(skb, nla_data(nested_attr)); 623 break; 624 } 625 626 return err; 627} 628 629static int execute_recirc(struct datapath *dp, struct sk_buff *skb, 630 struct sw_flow_key *key, 631 const struct nlattr *a, int rem) 632{ 633 struct deferred_action *da; 634 int err; 635 636 err = ovs_flow_key_update(skb, key); 637 if (err) 638 return err; 639 640 if (!last_action(a, rem)) { 641 /* Recirc action is the not the last action 642 * of the action list, need to clone the skb. 643 */ 644 skb = skb_clone(skb, GFP_ATOMIC); 645 646 /* Skip the recirc action when out of memory, but 647 * continue on with the rest of the action list. 648 */ 649 if (!skb) 650 return 0; 651 } 652 653 da = add_deferred_actions(skb, key, NULL); 654 if (da) { 655 da->pkt_key.recirc_id = nla_get_u32(a); 656 } else { 657 kfree_skb(skb); 658 659 if (net_ratelimit()) 660 pr_warn("%s: deferred action limit reached, drop recirc action\n", 661 ovs_dp_name(dp)); 662 } 663 664 return 0; 665} 666 667/* Execute a list of actions against 'skb'. */ 668static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, 669 struct sw_flow_key *key, 670 const struct nlattr *attr, int len) 671{ 672 /* Every output action needs a separate clone of 'skb', but the common 673 * case is just a single output action, so that doing a clone and 674 * then freeing the original skbuff is wasteful. So the following code 675 * is slightly obscure just to avoid that. */ 676 int prev_port = -1; 677 const struct nlattr *a; 678 int rem; 679 680 for (a = attr, rem = len; rem > 0; 681 a = nla_next(a, &rem)) { 682 int err = 0; 683 684 if (prev_port != -1) { 685 do_output(dp, skb_clone(skb, GFP_ATOMIC), prev_port); 686 prev_port = -1; 687 } 688 689 switch (nla_type(a)) { 690 case OVS_ACTION_ATTR_OUTPUT: 691 prev_port = nla_get_u32(a); 692 break; 693 694 case OVS_ACTION_ATTR_USERSPACE: 695 output_userspace(dp, skb, key, a); 696 break; 697 698 case OVS_ACTION_ATTR_HASH: 699 execute_hash(skb, key, a); 700 break; 701 702 case OVS_ACTION_ATTR_PUSH_VLAN: 703 err = push_vlan(skb, nla_data(a)); 704 if (unlikely(err)) /* skb already freed. */ 705 return err; 706 break; 707 708 case OVS_ACTION_ATTR_POP_VLAN: 709 err = pop_vlan(skb); 710 break; 711 712 case OVS_ACTION_ATTR_RECIRC: 713 err = execute_recirc(dp, skb, key, a, rem); 714 if (last_action(a, rem)) { 715 /* If this is the last action, the skb has 716 * been consumed or freed. 717 * Return immediately. 718 */ 719 return err; 720 } 721 break; 722 723 case OVS_ACTION_ATTR_SET: 724 err = execute_set_action(skb, nla_data(a)); 725 break; 726 727 case OVS_ACTION_ATTR_SAMPLE: 728 err = sample(dp, skb, key, a); 729 break; 730 } 731 732 if (unlikely(err)) { 733 kfree_skb(skb); 734 return err; 735 } 736 } 737 738 if (prev_port != -1) 739 do_output(dp, skb, prev_port); 740 else 741 consume_skb(skb); 742 743 return 0; 744} 745 746static void process_deferred_actions(struct datapath *dp) 747{ 748 struct action_fifo *fifo = this_cpu_ptr(action_fifos); 749 750 /* Do not touch the FIFO in case there is no deferred actions. */ 751 if (action_fifo_is_empty(fifo)) 752 return; 753 754 /* Finishing executing all deferred actions. */ 755 do { 756 struct deferred_action *da = action_fifo_get(fifo); 757 struct sk_buff *skb = da->skb; 758 struct sw_flow_key *key = &da->pkt_key; 759 const struct nlattr *actions = da->actions; 760 761 if (actions) 762 do_execute_actions(dp, skb, key, actions, 763 nla_len(actions)); 764 else 765 ovs_dp_process_packet(skb, key); 766 } while (!action_fifo_is_empty(fifo)); 767 768 /* Reset FIFO for the next packet. */ 769 action_fifo_init(fifo); 770} 771 772/* Execute a list of actions against 'skb'. */ 773int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, 774 struct sw_flow_key *key) 775{ 776 int level = this_cpu_read(exec_actions_level); 777 struct sw_flow_actions *acts; 778 int err; 779 780 acts = rcu_dereference(OVS_CB(skb)->flow->sf_acts); 781 782 this_cpu_inc(exec_actions_level); 783 OVS_CB(skb)->egress_tun_info = NULL; 784 err = do_execute_actions(dp, skb, key, 785 acts->actions, acts->actions_len); 786 787 if (!level) 788 process_deferred_actions(dp); 789 790 this_cpu_dec(exec_actions_level); 791 return err; 792} 793 794int action_fifos_init(void) 795{ 796 action_fifos = alloc_percpu(struct action_fifo); 797 if (!action_fifos) 798 return -ENOMEM; 799 800 return 0; 801} 802 803void action_fifos_exit(void) 804{ 805 free_percpu(action_fifos); 806} 807