drivers/net/tap/tap_flow.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright 2017 6WIND S.A.
   3  * Copyright 2017 Mellanox Technologies, Ltd
   4  */
   5
   6 #include <errno.h>
   7 #include <string.h>
   8 #include <unistd.h>
   9 #include <sys/queue.h>
  10 #include <sys/resource.h>
  11
  12 #include <rte_byteorder.h>
  13 #include <rte_jhash.h>
  14 #include <rte_malloc.h>
  15 #include <rte_eth_tap.h>
  16 #include <tap_flow.h>
  17 #include <tap_autoconf.h>
  18 #include <tap_tcmsgs.h>
  19 #include <tap_rss.h>
  20
  21 #ifndef HAVE_TC_FLOWER
  22 /*
  23  * For kernels < 4.2, this enum is not defined. Runtime checks will be made to
  24  * avoid sending TC messages the kernel cannot understand.
  25  */
  26 enum {
  27         TCA_FLOWER_UNSPEC,
  28         TCA_FLOWER_CLASSID,
  29         TCA_FLOWER_INDEV,
  30         TCA_FLOWER_ACT,
  31         TCA_FLOWER_KEY_ETH_DST,         /* ETH_ALEN */
  32         TCA_FLOWER_KEY_ETH_DST_MASK,    /* ETH_ALEN */
  33         TCA_FLOWER_KEY_ETH_SRC,         /* ETH_ALEN */
  34         TCA_FLOWER_KEY_ETH_SRC_MASK,    /* ETH_ALEN */
  35         TCA_FLOWER_KEY_ETH_TYPE,        /* be16 */
  36         TCA_FLOWER_KEY_IP_PROTO,        /* u8 */
  37         TCA_FLOWER_KEY_IPV4_SRC,        /* be32 */
  38         TCA_FLOWER_KEY_IPV4_SRC_MASK,   /* be32 */
  39         TCA_FLOWER_KEY_IPV4_DST,        /* be32 */
  40         TCA_FLOWER_KEY_IPV4_DST_MASK,   /* be32 */
  41         TCA_FLOWER_KEY_IPV6_SRC,        /* struct in6_addr */
  42         TCA_FLOWER_KEY_IPV6_SRC_MASK,   /* struct in6_addr */
  43         TCA_FLOWER_KEY_IPV6_DST,        /* struct in6_addr */
  44         TCA_FLOWER_KEY_IPV6_DST_MASK,   /* struct in6_addr */
  45         TCA_FLOWER_KEY_TCP_SRC,         /* be16 */
  46         TCA_FLOWER_KEY_TCP_DST,         /* be16 */
  47         TCA_FLOWER_KEY_UDP_SRC,         /* be16 */
  48         TCA_FLOWER_KEY_UDP_DST,         /* be16 */
  49 };
  50 #endif
  51 #ifndef HAVE_TC_VLAN_ID
  52 enum {
  53         /* TCA_FLOWER_FLAGS, */
  54         TCA_FLOWER_KEY_VLAN_ID = TCA_FLOWER_KEY_UDP_DST + 2, /* be16 */
  55         TCA_FLOWER_KEY_VLAN_PRIO,       /* u8   */
  56         TCA_FLOWER_KEY_VLAN_ETH_TYPE,   /* be16 */
  57 };
  58 #endif
  59 /*
  60  * For kernels < 4.2 BPF related enums may not be defined.
  61  * Runtime checks will be carried out to gracefully report on TC messages that
  62  * are rejected by the kernel. Rejection reasons may be due to:
  63  * 1. enum is not defined
  64  * 2. enum is defined but kernel is not configured to support BPF system calls,
  65  *    BPF classifications or BPF actions.
  66  */
  67 #ifndef HAVE_TC_BPF
  68 enum {
  69         TCA_BPF_UNSPEC,
  70         TCA_BPF_ACT,
  71         TCA_BPF_POLICE,
  72         TCA_BPF_CLASSID,
  73         TCA_BPF_OPS_LEN,
  74         TCA_BPF_OPS,
  75 };
  76 #endif
  77 #ifndef HAVE_TC_BPF_FD
  78 enum {
  79         TCA_BPF_FD = TCA_BPF_OPS + 1,
  80         TCA_BPF_NAME,
  81 };
  82 #endif
  83 #ifndef HAVE_TC_ACT_BPF
  84 #define tc_gen \
  85         __u32                 index; \
  86         __u32                 capab; \
  87         int                   action; \
  88         int                   refcnt; \
  89         int                   bindcnt
  90
  91 struct tc_act_bpf {
  92         tc_gen;
  93 };
  94
  95 enum {
  96         TCA_ACT_BPF_UNSPEC,
  97         TCA_ACT_BPF_TM,
  98         TCA_ACT_BPF_PARMS,
  99         TCA_ACT_BPF_OPS_LEN,
 100         TCA_ACT_BPF_OPS,
 101 };
 102
 103 #endif
 104 #ifndef HAVE_TC_ACT_BPF_FD
 105 enum {
 106         TCA_ACT_BPF_FD = TCA_ACT_BPF_OPS + 1,
 107         TCA_ACT_BPF_NAME,
 108 };
 109 #endif
 110
 111 /* RSS key management */
 112 enum bpf_rss_key_e {
 113         KEY_CMD_GET = 1,
 114         KEY_CMD_RELEASE,
 115         KEY_CMD_INIT,
 116         KEY_CMD_DEINIT,
 117 };
 118
 119 enum key_status_e {
 120         KEY_STAT_UNSPEC,
 121         KEY_STAT_USED,
 122         KEY_STAT_AVAILABLE,
 123 };
 124
 125 #define ISOLATE_HANDLE 1
 126 #define REMOTE_PROMISCUOUS_HANDLE 2
 127
 128 struct rte_flow {
 129         LIST_ENTRY(rte_flow) next; /* Pointer to the next rte_flow structure */
 130         struct rte_flow *remote_flow; /* associated remote flow */
 131         int bpf_fd[SEC_MAX]; /* list of bfs fds per ELF section */
 132         uint32_t key_idx; /* RSS rule key index into BPF map */
 133         struct nlmsg msg;
 134 };
 135
 136 struct convert_data {
 137         uint16_t eth_type;
 138         uint16_t ip_proto;
 139         uint8_t vlan;
 140         struct rte_flow *flow;
 141 };
 142
 143 struct remote_rule {
 144         struct rte_flow_attr attr;
 145         struct rte_flow_item items[2];
 146         struct rte_flow_action actions[2];
 147         int mirred;
 148 };
 149
 150 struct action_data {
 151         char id[16];
 152
 153         union {
 154                 struct tc_gact gact;
 155                 struct tc_mirred mirred;
 156                 struct skbedit {
 157                         struct tc_skbedit skbedit;
 158                         uint16_t queue;
 159                 } skbedit;
 160                 struct bpf {
 161                         struct tc_act_bpf bpf;
 162                         int bpf_fd;
 163                         const char *annotation;
 164                 } bpf;
 165         };
 166 };
 167
 168 static int tap_flow_create_eth(const struct rte_flow_item *item, void *data);
 169 static int tap_flow_create_vlan(const struct rte_flow_item *item, void *data);
 170 static int tap_flow_create_ipv4(const struct rte_flow_item *item, void *data);
 171 static int tap_flow_create_ipv6(const struct rte_flow_item *item, void *data);
 172 static int tap_flow_create_udp(const struct rte_flow_item *item, void *data);
 173 static int tap_flow_create_tcp(const struct rte_flow_item *item, void *data);
 174 static int
 175 tap_flow_validate(struct rte_eth_dev *dev,
 176                   const struct rte_flow_attr *attr,
 177                   const struct rte_flow_item items[],
 178                   const struct rte_flow_action actions[],
 179                   struct rte_flow_error *error);
 180
 181 static struct rte_flow *
 182 tap_flow_create(struct rte_eth_dev *dev,
 183                 const struct rte_flow_attr *attr,
 184                 const struct rte_flow_item items[],
 185                 const struct rte_flow_action actions[],
 186                 struct rte_flow_error *error);
 187
 188 static void
 189 tap_flow_free(struct pmd_internals *pmd,
 190         struct rte_flow *flow);
 191
 192 static int
 193 tap_flow_destroy(struct rte_eth_dev *dev,
 194                  struct rte_flow *flow,
 195                  struct rte_flow_error *error);
 196
 197 static int
 198 tap_flow_isolate(struct rte_eth_dev *dev,
 199                  int set,
 200                  struct rte_flow_error *error);
 201
 202 static int bpf_rss_key(enum bpf_rss_key_e cmd, __u32 *key_idx);
 203 static int rss_enable(struct pmd_internals *pmd,
 204                         const struct rte_flow_attr *attr,
 205                         struct rte_flow_error *error);
 206 static int rss_add_actions(struct rte_flow *flow, struct pmd_internals *pmd,
 207                         const struct rte_flow_action_rss *rss,
 208                         struct rte_flow_error *error);
 209
 210 static const struct rte_flow_ops tap_flow_ops = {
 211         .validate = tap_flow_validate,
 212         .create = tap_flow_create,
 213         .destroy = tap_flow_destroy,
 214         .flush = tap_flow_flush,
 215         .isolate = tap_flow_isolate,
 216 };
 217
 218 /* Static initializer for items. */
 219 #define ITEMS(...) \
 220         (const enum rte_flow_item_type []){ \
 221                 __VA_ARGS__, RTE_FLOW_ITEM_TYPE_END, \
 222         }
 223
 224 /* Structure to generate a simple graph of layers supported by the NIC. */
 225 struct tap_flow_items {
 226         /* Bit-mask corresponding to what is supported for this item. */
 227         const void *mask;
 228         const unsigned int mask_sz; /* Bit-mask size in bytes. */
 229         /*
 230          * Bit-mask corresponding to the default mask, if none is provided
 231          * along with the item.
 232          */
 233         const void *default_mask;
 234         /**
 235          * Conversion function from rte_flow to netlink attributes.
 236          *
 237          * @param item
 238          *   rte_flow item to convert.
 239          * @param data
 240          *   Internal structure to store the conversion.
 241          *
 242          * @return
 243          *   0 on success, negative value otherwise.
 244          */
 245         int (*convert)(const struct rte_flow_item *item, void *data);
 246         /** List of possible following items.  */
 247         const enum rte_flow_item_type *const items;
 248 };
 249
 250 /* Graph of supported items and associated actions. */
 251 static const struct tap_flow_items tap_flow_items[] = {
 252         [RTE_FLOW_ITEM_TYPE_END] = {
 253                 .items = ITEMS(RTE_FLOW_ITEM_TYPE_ETH),
 254         },
 255         [RTE_FLOW_ITEM_TYPE_ETH] = {
 256                 .items = ITEMS(
 257                         RTE_FLOW_ITEM_TYPE_VLAN,
 258                         RTE_FLOW_ITEM_TYPE_IPV4,
 259                         RTE_FLOW_ITEM_TYPE_IPV6),
 260                 .mask = &(const struct rte_flow_item_eth){
 261                         .dst.addr_bytes = "\xff\xff\xff\xff\xff\xff",
 262                         .src.addr_bytes = "\xff\xff\xff\xff\xff\xff",
 263                         .type = -1,
 264                 },
 265                 .mask_sz = sizeof(struct rte_flow_item_eth),
 266                 .default_mask = &rte_flow_item_eth_mask,
 267                 .convert = tap_flow_create_eth,
 268         },
 269         [RTE_FLOW_ITEM_TYPE_VLAN] = {
 270                 .items = ITEMS(RTE_FLOW_ITEM_TYPE_IPV4,
 271                                RTE_FLOW_ITEM_TYPE_IPV6),
 272                 .mask = &(const struct rte_flow_item_vlan){
 273                         /* DEI matching is not supported */
 274 #if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN
 275                         .tci = 0xffef,
 276 #else
 277                         .tci = 0xefff,
 278 #endif
 279                         .inner_type = -1,
 280                 },
 281                 .mask_sz = sizeof(struct rte_flow_item_vlan),
 282                 .default_mask = &rte_flow_item_vlan_mask,
 283                 .convert = tap_flow_create_vlan,
 284         },
 285         [RTE_FLOW_ITEM_TYPE_IPV4] = {
 286                 .items = ITEMS(RTE_FLOW_ITEM_TYPE_UDP,
 287                                RTE_FLOW_ITEM_TYPE_TCP),
 288                 .mask = &(const struct rte_flow_item_ipv4){
 289                         .hdr = {
 290                                 .src_addr = -1,
 291                                 .dst_addr = -1,
 292                                 .next_proto_id = -1,
 293                         },
 294                 },
 295                 .mask_sz = sizeof(struct rte_flow_item_ipv4),
 296                 .default_mask = &rte_flow_item_ipv4_mask,
 297                 .convert = tap_flow_create_ipv4,
 298         },
 299         [RTE_FLOW_ITEM_TYPE_IPV6] = {
 300                 .items = ITEMS(RTE_FLOW_ITEM_TYPE_UDP,
 301                                RTE_FLOW_ITEM_TYPE_TCP),
 302                 .mask = &(const struct rte_flow_item_ipv6){
 303                         .hdr = {
 304                                 .src_addr = {
 305                                         "\xff\xff\xff\xff\xff\xff\xff\xff"
 306                                         "\xff\xff\xff\xff\xff\xff\xff\xff",
 307                                 },
 308                                 .dst_addr = {
 309                                         "\xff\xff\xff\xff\xff\xff\xff\xff"
 310                                         "\xff\xff\xff\xff\xff\xff\xff\xff",
 311                                 },
 312                                 .proto = -1,
 313                         },
 314                 },
 315                 .mask_sz = sizeof(struct rte_flow_item_ipv6),
 316                 .default_mask = &rte_flow_item_ipv6_mask,
 317                 .convert = tap_flow_create_ipv6,
 318         },
 319         [RTE_FLOW_ITEM_TYPE_UDP] = {
 320                 .mask = &(const struct rte_flow_item_udp){
 321                         .hdr = {
 322                                 .src_port = -1,
 323                                 .dst_port = -1,
 324                         },
 325                 },
 326                 .mask_sz = sizeof(struct rte_flow_item_udp),
 327                 .default_mask = &rte_flow_item_udp_mask,
 328                 .convert = tap_flow_create_udp,
 329         },
 330         [RTE_FLOW_ITEM_TYPE_TCP] = {
 331                 .mask = &(const struct rte_flow_item_tcp){
 332                         .hdr = {
 333                                 .src_port = -1,
 334                                 .dst_port = -1,
 335                         },
 336                 },
 337                 .mask_sz = sizeof(struct rte_flow_item_tcp),
 338                 .default_mask = &rte_flow_item_tcp_mask,
 339                 .convert = tap_flow_create_tcp,
 340         },
 341 };
 342
 343 /*
 344  *                TC rules, by growing priority
 345  *
 346  *        Remote netdevice                  Tap netdevice
 347  * +-------------+-------------+  +-------------+-------------+
 348  * |   Ingress   |   Egress    |  |   Ingress   |   Egress    |
 349  * |-------------|-------------|  |-------------|-------------|
 350  * |             |  \       /  |  |             |  REMOTE TX  | prio 1
 351  * |             |   \     /   |  |             |   \     /   | prio 2
 352  * |  EXPLICIT   |    \   /    |  |  EXPLICIT   |    \   /    |   .
 353  * |             |     \ /     |  |             |     \ /     |   .
 354  * |    RULES    |      X      |  |    RULES    |      X      |   .
 355  * |      .      |     / \     |  |      .      |     / \     |   .
 356  * |      .      |    /   \    |  |      .      |    /   \    |   .
 357  * |      .      |   /     \   |  |      .      |   /     \   |   .
 358  * |      .      |  /       \  |  |      .      |  /       \  |   .
 359  *
 360  *      ....           ....           ....           ....
 361  *
 362  * |      .      |  \       /  |  |      .      |  \       /  |   .
 363  * |      .      |   \     /   |  |      .      |   \     /   |   .
 364  * |             |    \   /    |  |             |    \   /    |
 365  * |  LOCAL_MAC  |     \ /     |  |    \   /    |     \ /     | last prio - 5
 366  * |   PROMISC   |      X      |  |     \ /     |      X      | last prio - 4
 367  * |   ALLMULTI  |     / \     |  |      X      |     / \     | last prio - 3
 368  * |  BROADCAST  |    /   \    |  |     / \     |    /   \    | last prio - 2
 369  * | BROADCASTV6 |   /     \   |  |    /   \    |   /     \   | last prio - 1
 370  * |     xx      |  /       \  |  |   ISOLATE   |  /       \  | last prio
 371  * +-------------+-------------+  +-------------+-------------+
 372  *
 373  * The implicit flow rules are stored in a list in with mandatorily the last two
 374  * being the ISOLATE and REMOTE_TX rules. e.g.:
 375  *
 376  * LOCAL_MAC -> BROADCAST -> BROADCASTV6 -> REMOTE_TX -> ISOLATE -> NULL
 377  *
 378  * That enables tap_flow_isolate() to remove implicit rules by popping the list
 379  * head and remove it as long as it applies on the remote netdevice. The
 380  * implicit rule for TX redirection is not removed, as isolate concerns only
 381  * incoming traffic.
 382  */
 383
 384 static struct remote_rule implicit_rte_flows[TAP_REMOTE_MAX_IDX] = {
 385         [TAP_REMOTE_LOCAL_MAC] = {
 386                 .attr = {
 387                         .group = MAX_GROUP,
 388                         .priority = PRIORITY_MASK - TAP_REMOTE_LOCAL_MAC,
 389                         .ingress = 1,
 390                 },
 391                 .items[0] = {
 392                         .type = RTE_FLOW_ITEM_TYPE_ETH,
 393                         .mask =  &(const struct rte_flow_item_eth){
 394                                 .dst.addr_bytes = "\xff\xff\xff\xff\xff\xff",
 395                         },
 396                 },
 397                 .items[1] = {
 398                         .type = RTE_FLOW_ITEM_TYPE_END,
 399                 },
 400                 .mirred = TCA_EGRESS_REDIR,
 401         },
 402         [TAP_REMOTE_BROADCAST] = {
 403                 .attr = {
 404                         .group = MAX_GROUP,
 405                         .priority = PRIORITY_MASK - TAP_REMOTE_BROADCAST,
 406                         .ingress = 1,
 407                 },
 408                 .items[0] = {
 409                         .type = RTE_FLOW_ITEM_TYPE_ETH,
 410                         .mask =  &(const struct rte_flow_item_eth){
 411                                 .dst.addr_bytes = "\xff\xff\xff\xff\xff\xff",
 412                         },
 413                         .spec = &(const struct rte_flow_item_eth){
 414                                 .dst.addr_bytes = "\xff\xff\xff\xff\xff\xff",
 415                         },
 416                 },
 417                 .items[1] = {
 418                         .type = RTE_FLOW_ITEM_TYPE_END,
 419                 },
 420                 .mirred = TCA_EGRESS_MIRROR,
 421         },
 422         [TAP_REMOTE_BROADCASTV6] = {
 423                 .attr = {
 424                         .group = MAX_GROUP,
 425                         .priority = PRIORITY_MASK - TAP_REMOTE_BROADCASTV6,
 426                         .ingress = 1,
 427                 },
 428                 .items[0] = {
 429                         .type = RTE_FLOW_ITEM_TYPE_ETH,
 430                         .mask =  &(const struct rte_flow_item_eth){
 431                                 .dst.addr_bytes = "\x33\x33\x00\x00\x00\x00",
 432                         },
 433                         .spec = &(const struct rte_flow_item_eth){
 434                                 .dst.addr_bytes = "\x33\x33\x00\x00\x00\x00",
 435                         },
 436                 },
 437                 .items[1] = {
 438                         .type = RTE_FLOW_ITEM_TYPE_END,
 439                 },
 440                 .mirred = TCA_EGRESS_MIRROR,
 441         },
 442         [TAP_REMOTE_PROMISC] = {
 443                 .attr = {
 444                         .group = MAX_GROUP,
 445                         .priority = PRIORITY_MASK - TAP_REMOTE_PROMISC,
 446                         .ingress = 1,
 447                 },
 448                 .items[0] = {
 449                         .type = RTE_FLOW_ITEM_TYPE_VOID,
 450                 },
 451                 .items[1] = {
 452                         .type = RTE_FLOW_ITEM_TYPE_END,
 453                 },
 454                 .mirred = TCA_EGRESS_MIRROR,
 455         },
 456         [TAP_REMOTE_ALLMULTI] = {
 457                 .attr = {
 458                         .group = MAX_GROUP,
 459                         .priority = PRIORITY_MASK - TAP_REMOTE_ALLMULTI,
 460                         .ingress = 1,
 461                 },
 462                 .items[0] = {
 463                         .type = RTE_FLOW_ITEM_TYPE_ETH,
 464                         .mask =  &(const struct rte_flow_item_eth){
 465                                 .dst.addr_bytes = "\x01\x00\x00\x00\x00\x00",
 466                         },
 467                         .spec = &(const struct rte_flow_item_eth){
 468                                 .dst.addr_bytes = "\x01\x00\x00\x00\x00\x00",
 469                         },
 470                 },
 471                 .items[1] = {
 472                         .type = RTE_FLOW_ITEM_TYPE_END,
 473                 },
 474                 .mirred = TCA_EGRESS_MIRROR,
 475         },
 476         [TAP_REMOTE_TX] = {
 477                 .attr = {
 478                         .group = 0,
 479                         .priority = TAP_REMOTE_TX,
 480                         .egress = 1,
 481                 },
 482                 .items[0] = {
 483                         .type = RTE_FLOW_ITEM_TYPE_VOID,
 484                 },
 485                 .items[1] = {
 486                         .type = RTE_FLOW_ITEM_TYPE_END,
 487                 },
 488                 .mirred = TCA_EGRESS_MIRROR,
 489         },
 490         [TAP_ISOLATE] = {
 491                 .attr = {
 492                         .group = MAX_GROUP,
 493                         .priority = PRIORITY_MASK - TAP_ISOLATE,
 494                         .ingress = 1,
 495                 },
 496                 .items[0] = {
 497                         .type = RTE_FLOW_ITEM_TYPE_VOID,
 498                 },
 499                 .items[1] = {
 500                         .type = RTE_FLOW_ITEM_TYPE_END,
 501                 },
 502         },
 503 };
 504
 505 /**
 506  * Make as much checks as possible on an Ethernet item, and if a flow is
 507  * provided, fill it appropriately with Ethernet info.
 508  *
 509  * @param[in] item
 510  *   Item specification.
 511  * @param[in, out] data
 512  *   Additional data structure to tell next layers we've been here.
 513  *
 514  * @return
 515  *   0 if checks are alright, -1 otherwise.
 516  */
 517 static int
 518 tap_flow_create_eth(const struct rte_flow_item *item, void *data)
 519 {
 520         struct convert_data *info = (struct convert_data *)data;
 521         const struct rte_flow_item_eth *spec = item->spec;
 522         const struct rte_flow_item_eth *mask = item->mask;
 523         struct rte_flow *flow = info->flow;
 524         struct nlmsg *msg;
 525
 526         /* use default mask if none provided */
 527         if (!mask)
 528                 mask = tap_flow_items[RTE_FLOW_ITEM_TYPE_ETH].default_mask;
 529         /* TC does not support eth_type masking. Only accept if exact match. */
 530         if (mask->type && mask->type != 0xffff)
 531                 return -1;
 532         if (!spec)
 533                 return 0;
 534         /* store eth_type for consistency if ipv4/6 pattern item comes next */
 535         if (spec->type & mask->type)
 536                 info->eth_type = spec->type;
 537         if (!flow)
 538                 return 0;
 539         msg = &flow->msg;
 540         if (!rte_is_zero_ether_addr(&mask->dst)) {
 541                 tap_nlattr_add(&msg->nh, TCA_FLOWER_KEY_ETH_DST,
 542                         RTE_ETHER_ADDR_LEN,
 543                            &spec->dst.addr_bytes);
 544                 tap_nlattr_add(&msg->nh,
 545                            TCA_FLOWER_KEY_ETH_DST_MASK, RTE_ETHER_ADDR_LEN,
 546                            &mask->dst.addr_bytes);
 547         }
 548         if (!rte_is_zero_ether_addr(&mask->src)) {
 549                 tap_nlattr_add(&msg->nh, TCA_FLOWER_KEY_ETH_SRC,
 550                         RTE_ETHER_ADDR_LEN,
 551                         &spec->src.addr_bytes);
 552                 tap_nlattr_add(&msg->nh,
 553                            TCA_FLOWER_KEY_ETH_SRC_MASK, RTE_ETHER_ADDR_LEN,
 554                            &mask->src.addr_bytes);
 555         }
 556         return 0;
 557 }
 558
 559 /**
 560  * Make as much checks as possible on a VLAN item, and if a flow is provided,
 561  * fill it appropriately with VLAN info.
 562  *
 563  * @param[in] item
 564  *   Item specification.
 565  * @param[in, out] data
 566  *   Additional data structure to tell next layers we've been here.
 567  *
 568  * @return
 569  *   0 if checks are alright, -1 otherwise.
 570  */
 571 static int
 572 tap_flow_create_vlan(const struct rte_flow_item *item, void *data)
 573 {
 574         struct convert_data *info = (struct convert_data *)data;
 575         const struct rte_flow_item_vlan *spec = item->spec;
 576         const struct rte_flow_item_vlan *mask = item->mask;
 577         struct rte_flow *flow = info->flow;
 578         struct nlmsg *msg;
 579
 580         /* use default mask if none provided */
 581         if (!mask)
 582                 mask = tap_flow_items[RTE_FLOW_ITEM_TYPE_VLAN].default_mask;
 583         /* Outer TPID cannot be matched. */
 584         if (info->eth_type)
 585                 return -1;
 586         /* Double-tagging not supported. */
 587         if (info->vlan)
 588                 return -1;
 589         info->vlan = 1;
 590         if (mask->inner_type) {
 591                 /* TC does not support partial eth_type masking */
 592                 if (mask->inner_type != RTE_BE16(0xffff))
 593                         return -1;
 594                 info->eth_type = spec->inner_type;
 595         }
 596         if (!flow)
 597                 return 0;
 598         msg = &flow->msg;
 599         msg->t.tcm_info = TC_H_MAKE(msg->t.tcm_info, htons(ETH_P_8021Q));
 600 #define VLAN_PRIO(tci) ((tci) >> 13)
 601 #define VLAN_ID(tci) ((tci) & 0xfff)
 602         if (!spec)
 603                 return 0;
 604         if (spec->tci) {
 605                 uint16_t tci = ntohs(spec->tci) & mask->tci;
 606                 uint16_t prio = VLAN_PRIO(tci);
 607                 uint8_t vid = VLAN_ID(tci);
 608
 609                 if (prio)
 610                         tap_nlattr_add8(&msg->nh,
 611                                         TCA_FLOWER_KEY_VLAN_PRIO, prio);
 612                 if (vid)
 613                         tap_nlattr_add16(&msg->nh,
 614                                          TCA_FLOWER_KEY_VLAN_ID, vid);
 615         }
 616         return 0;
 617 }
 618
 619 /**
 620  * Make as much checks as possible on an IPv4 item, and if a flow is provided,
 621  * fill it appropriately with IPv4 info.
 622  *
 623  * @param[in] item
 624  *   Item specification.
 625  * @param[in, out] data
 626  *   Additional data structure to tell next layers we've been here.
 627  *
 628  * @return
 629  *   0 if checks are alright, -1 otherwise.
 630  */
 631 static int
 632 tap_flow_create_ipv4(const struct rte_flow_item *item, void *data)
 633 {
 634         struct convert_data *info = (struct convert_data *)data;
 635         const struct rte_flow_item_ipv4 *spec = item->spec;
 636         const struct rte_flow_item_ipv4 *mask = item->mask;
 637         struct rte_flow *flow = info->flow;
 638         struct nlmsg *msg;
 639
 640         /* use default mask if none provided */
 641         if (!mask)
 642                 mask = tap_flow_items[RTE_FLOW_ITEM_TYPE_IPV4].default_mask;
 643         /* check that previous eth type is compatible with ipv4 */
 644         if (info->eth_type && info->eth_type != htons(ETH_P_IP))
 645                 return -1;
 646         /* store ip_proto for consistency if udp/tcp pattern item comes next */
 647         if (spec)
 648                 info->ip_proto = spec->hdr.next_proto_id;
 649         if (!flow)
 650                 return 0;
 651         msg = &flow->msg;
 652         if (!info->eth_type)
 653                 info->eth_type = htons(ETH_P_IP);
 654         if (!spec)
 655                 return 0;
 656         if (mask->hdr.dst_addr) {
 657                 tap_nlattr_add32(&msg->nh, TCA_FLOWER_KEY_IPV4_DST,
 658                              spec->hdr.dst_addr);
 659                 tap_nlattr_add32(&msg->nh, TCA_FLOWER_KEY_IPV4_DST_MASK,
 660                              mask->hdr.dst_addr);
 661         }
 662         if (mask->hdr.src_addr) {
 663                 tap_nlattr_add32(&msg->nh, TCA_FLOWER_KEY_IPV4_SRC,
 664                              spec->hdr.src_addr);
 665                 tap_nlattr_add32(&msg->nh, TCA_FLOWER_KEY_IPV4_SRC_MASK,
 666                              mask->hdr.src_addr);
 667         }
 668         if (spec->hdr.next_proto_id)
 669                 tap_nlattr_add8(&msg->nh, TCA_FLOWER_KEY_IP_PROTO,
 670                             spec->hdr.next_proto_id);
 671         return 0;
 672 }
 673
 674 /**
 675  * Make as much checks as possible on an IPv6 item, and if a flow is provided,
 676  * fill it appropriately with IPv6 info.
 677  *
 678  * @param[in] item
 679  *   Item specification.
 680  * @param[in, out] data
 681  *   Additional data structure to tell next layers we've been here.
 682  *
 683  * @return
 684  *   0 if checks are alright, -1 otherwise.
 685  */
 686 static int
 687 tap_flow_create_ipv6(const struct rte_flow_item *item, void *data)
 688 {
 689         struct convert_data *info = (struct convert_data *)data;
 690         const struct rte_flow_item_ipv6 *spec = item->spec;
 691         const struct rte_flow_item_ipv6 *mask = item->mask;
 692         struct rte_flow *flow = info->flow;
 693         uint8_t empty_addr[16] = { 0 };
 694         struct nlmsg *msg;
 695
 696         /* use default mask if none provided */
 697         if (!mask)
 698                 mask = tap_flow_items[RTE_FLOW_ITEM_TYPE_IPV6].default_mask;
 699         /* check that previous eth type is compatible with ipv6 */
 700         if (info->eth_type && info->eth_type != htons(ETH_P_IPV6))
 701                 return -1;
 702         /* store ip_proto for consistency if udp/tcp pattern item comes next */
 703         if (spec)
 704                 info->ip_proto = spec->hdr.proto;
 705         if (!flow)
 706                 return 0;
 707         msg = &flow->msg;
 708         if (!info->eth_type)
 709                 info->eth_type = htons(ETH_P_IPV6);
 710         if (!spec)
 711                 return 0;
 712         if (memcmp(mask->hdr.dst_addr, empty_addr, 16)) {
 713                 tap_nlattr_add(&msg->nh, TCA_FLOWER_KEY_IPV6_DST,
 714                            sizeof(spec->hdr.dst_addr), &spec->hdr.dst_addr);
 715                 tap_nlattr_add(&msg->nh, TCA_FLOWER_KEY_IPV6_DST_MASK,
 716                            sizeof(mask->hdr.dst_addr), &mask->hdr.dst_addr);
 717         }
 718         if (memcmp(mask->hdr.src_addr, empty_addr, 16)) {
 719                 tap_nlattr_add(&msg->nh, TCA_FLOWER_KEY_IPV6_SRC,
 720                            sizeof(spec->hdr.src_addr), &spec->hdr.src_addr);
 721                 tap_nlattr_add(&msg->nh, TCA_FLOWER_KEY_IPV6_SRC_MASK,
 722                            sizeof(mask->hdr.src_addr), &mask->hdr.src_addr);
 723         }
 724         if (spec->hdr.proto)
 725                 tap_nlattr_add8(&msg->nh,
 726                                 TCA_FLOWER_KEY_IP_PROTO, spec->hdr.proto);
 727         return 0;
 728 }
 729
 730 /**
 731  * Make as much checks as possible on a UDP item, and if a flow is provided,
 732  * fill it appropriately with UDP info.
 733  *
 734  * @param[in] item
 735  *   Item specification.
 736  * @param[in, out] data
 737  *   Additional data structure to tell next layers we've been here.
 738  *
 739  * @return
 740  *   0 if checks are alright, -1 otherwise.
 741  */
 742 static int
 743 tap_flow_create_udp(const struct rte_flow_item *item, void *data)
 744 {
 745         struct convert_data *info = (struct convert_data *)data;
 746         const struct rte_flow_item_udp *spec = item->spec;
 747         const struct rte_flow_item_udp *mask = item->mask;
 748         struct rte_flow *flow = info->flow;
 749         struct nlmsg *msg;
 750
 751         /* use default mask if none provided */
 752         if (!mask)
 753                 mask = tap_flow_items[RTE_FLOW_ITEM_TYPE_UDP].default_mask;
 754         /* check that previous ip_proto is compatible with udp */
 755         if (info->ip_proto && info->ip_proto != IPPROTO_UDP)
 756                 return -1;
 757         /* TC does not support UDP port masking. Only accept if exact match. */
 758         if ((mask->hdr.src_port && mask->hdr.src_port != 0xffff) ||
 759             (mask->hdr.dst_port && mask->hdr.dst_port != 0xffff))
 760                 return -1;
 761         if (!flow)
 762                 return 0;
 763         msg = &flow->msg;
 764         tap_nlattr_add8(&msg->nh, TCA_FLOWER_KEY_IP_PROTO, IPPROTO_UDP);
 765         if (!spec)
 766                 return 0;
 767         if (mask->hdr.dst_port)
 768                 tap_nlattr_add16(&msg->nh, TCA_FLOWER_KEY_UDP_DST,
 769                              spec->hdr.dst_port);
 770         if (mask->hdr.src_port)
 771                 tap_nlattr_add16(&msg->nh, TCA_FLOWER_KEY_UDP_SRC,
 772                              spec->hdr.src_port);
 773         return 0;
 774 }
 775
 776 /**
 777  * Make as much checks as possible on a TCP item, and if a flow is provided,
 778  * fill it appropriately with TCP info.
 779  *
 780  * @param[in] item
 781  *   Item specification.
 782  * @param[in, out] data
 783  *   Additional data structure to tell next layers we've been here.
 784  *
 785  * @return
 786  *   0 if checks are alright, -1 otherwise.
 787  */
 788 static int
 789 tap_flow_create_tcp(const struct rte_flow_item *item, void *data)
 790 {
 791         struct convert_data *info = (struct convert_data *)data;
 792         const struct rte_flow_item_tcp *spec = item->spec;
 793         const struct rte_flow_item_tcp *mask = item->mask;
 794         struct rte_flow *flow = info->flow;
 795         struct nlmsg *msg;
 796
 797         /* use default mask if none provided */
 798         if (!mask)
 799                 mask = tap_flow_items[RTE_FLOW_ITEM_TYPE_TCP].default_mask;
 800         /* check that previous ip_proto is compatible with tcp */
 801         if (info->ip_proto && info->ip_proto != IPPROTO_TCP)
 802                 return -1;
 803         /* TC does not support TCP port masking. Only accept if exact match. */
 804         if ((mask->hdr.src_port && mask->hdr.src_port != 0xffff) ||
 805             (mask->hdr.dst_port && mask->hdr.dst_port != 0xffff))
 806                 return -1;
 807         if (!flow)
 808                 return 0;
 809         msg = &flow->msg;
 810         tap_nlattr_add8(&msg->nh, TCA_FLOWER_KEY_IP_PROTO, IPPROTO_TCP);
 811         if (!spec)
 812                 return 0;
 813         if (mask->hdr.dst_port)
 814                 tap_nlattr_add16(&msg->nh, TCA_FLOWER_KEY_TCP_DST,
 815                              spec->hdr.dst_port);
 816         if (mask->hdr.src_port)
 817                 tap_nlattr_add16(&msg->nh, TCA_FLOWER_KEY_TCP_SRC,
 818                              spec->hdr.src_port);
 819         return 0;
 820 }
 821
 822 /**
 823  * Check support for a given item.
 824  *
 825  * @param[in] item
 826  *   Item specification.
 827  * @param size
 828  *   Bit-Mask size in bytes.
 829  * @param[in] supported_mask
 830  *   Bit-mask covering supported fields to compare with spec, last and mask in
 831  *   \item.
 832  * @param[in] default_mask
 833  *   Bit-mask default mask if none is provided in \item.
 834  *
 835  * @return
 836  *   0 on success.
 837  */
 838 static int
 839 tap_flow_item_validate(const struct rte_flow_item *item,
 840                        unsigned int size,
 841                        const uint8_t *supported_mask,
 842                        const uint8_t *default_mask)
 843 {
 844         int ret = 0;
 845
 846         /* An empty layer is allowed, as long as all fields are NULL */
 847         if (!item->spec && (item->mask || item->last))
 848                 return -1;
 849         /* Is the item spec compatible with what the NIC supports? */
 850         if (item->spec && !item->mask) {
 851                 unsigned int i;
 852                 const uint8_t *spec = item->spec;
 853
 854                 for (i = 0; i < size; ++i)
 855                         if ((spec[i] | supported_mask[i]) != supported_mask[i])
 856                                 return -1;
 857                 /* Is the default mask compatible with what the NIC supports? */
 858                 for (i = 0; i < size; i++)
 859                         if ((default_mask[i] | supported_mask[i]) !=
 860                             supported_mask[i])
 861                                 return -1;
 862         }
 863         /* Is the item last compatible with what the NIC supports? */
 864         if (item->last && !item->mask) {
 865                 unsigned int i;
 866                 const uint8_t *spec = item->last;
 867
 868                 for (i = 0; i < size; ++i)
 869                         if ((spec[i] | supported_mask[i]) != supported_mask[i])
 870                                 return -1;
 871         }
 872         /* Is the item mask compatible with what the NIC supports? */
 873         if (item->mask) {
 874                 unsigned int i;
 875                 const uint8_t *spec = item->mask;
 876
 877                 for (i = 0; i < size; ++i)
 878                         if ((spec[i] | supported_mask[i]) != supported_mask[i])
 879                                 return -1;
 880         }
 881         /**
 882          * Once masked, Are item spec and item last equal?
 883          * TC does not support range so anything else is invalid.
 884          */
 885         if (item->spec && item->last) {
 886                 uint8_t spec[size];
 887                 uint8_t last[size];
 888                 const uint8_t *apply = default_mask;
 889                 unsigned int i;
 890
 891                 if (item->mask)
 892                         apply = item->mask;
 893                 for (i = 0; i < size; ++i) {
 894                         spec[i] = ((const uint8_t *)item->spec)[i] & apply[i];
 895                         last[i] = ((const uint8_t *)item->last)[i] & apply[i];
 896                 }
 897                 ret = memcmp(spec, last, size);
 898         }
 899         return ret;
 900 }
 901
 902 /**
 903  * Configure the kernel with a TC action and its configured parameters
 904  * Handled actions: "gact", "mirred", "skbedit", "bpf"
 905  *
 906  * @param[in] flow
 907  *   Pointer to rte flow containing the netlink message
 908  *
 909  * @param[in, out] act_index
 910  *   Pointer to action sequence number in the TC command
 911  *
 912  * @param[in] adata
 913  *  Pointer to struct holding the action parameters
 914  *
 915  * @return
 916  *   -1 on failure, 0 on success
 917  */
 918 static int
 919 add_action(struct rte_flow *flow, size_t *act_index, struct action_data *adata)
 920 {
 921         struct nlmsg *msg = &flow->msg;
 922
 923         if (tap_nlattr_nested_start(msg, (*act_index)++) < 0)
 924                 return -1;
 925
 926         tap_nlattr_add(&msg->nh, TCA_ACT_KIND,
 927                                 strlen(adata->id) + 1, adata->id);
 928         if (tap_nlattr_nested_start(msg, TCA_ACT_OPTIONS) < 0)
 929                 return -1;
 930         if (strcmp("gact", adata->id) == 0) {
 931                 tap_nlattr_add(&msg->nh, TCA_GACT_PARMS, sizeof(adata->gact),
 932                            &adata->gact);
 933         } else if (strcmp("mirred", adata->id) == 0) {
 934                 if (adata->mirred.eaction == TCA_EGRESS_MIRROR)
 935                         adata->mirred.action = TC_ACT_PIPE;
 936                 else /* REDIRECT */
 937                         adata->mirred.action = TC_ACT_STOLEN;
 938                 tap_nlattr_add(&msg->nh, TCA_MIRRED_PARMS,
 939                            sizeof(adata->mirred),
 940                            &adata->mirred);
 941         } else if (strcmp("skbedit", adata->id) == 0) {
 942                 tap_nlattr_add(&msg->nh, TCA_SKBEDIT_PARMS,
 943                            sizeof(adata->skbedit.skbedit),
 944                            &adata->skbedit.skbedit);
 945                 tap_nlattr_add16(&msg->nh, TCA_SKBEDIT_QUEUE_MAPPING,
 946                              adata->skbedit.queue);
 947         } else if (strcmp("bpf", adata->id) == 0) {
 948                 tap_nlattr_add32(&msg->nh, TCA_ACT_BPF_FD, adata->bpf.bpf_fd);
 949                 tap_nlattr_add(&msg->nh, TCA_ACT_BPF_NAME,
 950                            strlen(adata->bpf.annotation) + 1,
 951                            adata->bpf.annotation);
 952                 tap_nlattr_add(&msg->nh, TCA_ACT_BPF_PARMS,
 953                            sizeof(adata->bpf.bpf),
 954                            &adata->bpf.bpf);
 955         } else {
 956                 return -1;
 957         }
 958         tap_nlattr_nested_finish(msg); /* nested TCA_ACT_OPTIONS */
 959         tap_nlattr_nested_finish(msg); /* nested act_index */
 960         return 0;
 961 }
 962
 963 /**
 964  * Helper function to send a serie of TC actions to the kernel
 965  *
 966  * @param[in] flow
 967  *   Pointer to rte flow containing the netlink message
 968  *
 969  * @param[in] nb_actions
 970  *   Number of actions in an array of action structs
 971  *
 972  * @param[in] data
 973  *   Pointer to an array of action structs
 974  *
 975  * @param[in] classifier_actions
 976  *   The classifier on behave of which the actions are configured
 977  *
 978  * @return
 979  *   -1 on failure, 0 on success
 980  */
 981 static int
 982 add_actions(struct rte_flow *flow, int nb_actions, struct action_data *data,
 983             int classifier_action)
 984 {
 985         struct nlmsg *msg = &flow->msg;
 986         size_t act_index = 1;
 987         int i;
 988
 989         if (tap_nlattr_nested_start(msg, classifier_action) < 0)
 990                 return -1;
 991         for (i = 0; i < nb_actions; i++)
 992                 if (add_action(flow, &act_index, data + i) < 0)
 993                         return -1;
 994         tap_nlattr_nested_finish(msg); /* nested TCA_FLOWER_ACT */
 995         return 0;
 996 }
 997
 998 /**
 999  * Validate a flow supported by TC.
1000  * If flow param is not NULL, then also fill the netlink message inside.
1001  *
1002  * @param pmd
1003  *   Pointer to private structure.
1004  * @param[in] attr
1005  *   Flow rule attributes.
1006  * @param[in] pattern
1007  *   Pattern specification (list terminated by the END pattern item).
1008  * @param[in] actions
1009  *   Associated actions (list terminated by the END action).
1010  * @param[out] error
1011  *   Perform verbose error reporting if not NULL.
1012  * @param[in, out] flow
1013  *   Flow structure to update.
1014  * @param[in] mirred
1015  *   If set to TCA_EGRESS_REDIR, provided actions will be replaced with a
1016  *   redirection to the tap netdevice, and the TC rule will be configured
1017  *   on the remote netdevice in pmd.
1018  *   If set to TCA_EGRESS_MIRROR, provided actions will be replaced with a
1019  *   mirroring to the tap netdevice, and the TC rule will be configured
1020  *   on the remote netdevice in pmd. Matching packets will thus be duplicated.
1021  *   If set to 0, the standard behavior is to be used: set correct actions for
1022  *   the TC rule, and apply it on the tap netdevice.
1023  *
1024  * @return
1025  *   0 on success, a negative errno value otherwise and rte_errno is set.
1026  */
1027 static int
1028 priv_flow_process(struct pmd_internals *pmd,
1029                   const struct rte_flow_attr *attr,
1030                   const struct rte_flow_item items[],
1031                   const struct rte_flow_action actions[],
1032                   struct rte_flow_error *error,
1033                   struct rte_flow *flow,
1034                   int mirred)
1035 {
1036         const struct tap_flow_items *cur_item = tap_flow_items;
1037         struct convert_data data = {
1038                 .eth_type = 0,
1039                 .ip_proto = 0,
1040                 .flow = flow,
1041         };
1042         int action = 0; /* Only one action authorized for now */
1043
1044         if (attr->transfer) {
1045                 rte_flow_error_set(
1046                         error, ENOTSUP, RTE_FLOW_ERROR_TYPE_ATTR_TRANSFER,
1047                         NULL, "transfer is not supported");
1048                 return -rte_errno;
1049         }
1050         if (attr->group > MAX_GROUP) {
1051                 rte_flow_error_set(
1052                         error, EINVAL, RTE_FLOW_ERROR_TYPE_ATTR_GROUP,
1053                         NULL, "group value too big: cannot exceed 15");
1054                 return -rte_errno;
1055         }
1056         if (attr->priority > MAX_PRIORITY) {
1057                 rte_flow_error_set(
1058                         error, EINVAL, RTE_FLOW_ERROR_TYPE_ATTR_PRIORITY,
1059                         NULL, "priority value too big");
1060                 return -rte_errno;
1061         } else if (flow) {
1062                 uint16_t group = attr->group << GROUP_SHIFT;
1063                 uint16_t prio = group | (attr->priority +
1064                                 RSS_PRIORITY_OFFSET + PRIORITY_OFFSET);
1065                 flow->msg.t.tcm_info = TC_H_MAKE(prio << 16,
1066                                                  flow->msg.t.tcm_info);
1067         }
1068         if (flow) {
1069                 if (mirred) {
1070                         /*
1071                          * If attr->ingress, the rule applies on remote ingress
1072                          * to match incoming packets
1073                          * If attr->egress, the rule applies on tap ingress (as
1074                          * seen from the kernel) to deal with packets going out
1075                          * from the DPDK app.
1076                          */
1077                         flow->msg.t.tcm_parent = TC_H_MAKE(TC_H_INGRESS, 0);
1078                 } else {
1079                         /* Standard rule on tap egress (kernel standpoint). */
1080                         flow->msg.t.tcm_parent =
1081                                 TC_H_MAKE(MULTIQ_MAJOR_HANDLE, 0);
1082                 }
1083                 /* use flower filter type */
1084                 tap_nlattr_add(&flow->msg.nh, TCA_KIND, sizeof("flower"), "flower");
1085                 if (tap_nlattr_nested_start(&flow->msg, TCA_OPTIONS) < 0)
1086                         goto exit_item_not_supported;
1087         }
1088         for (; items->type != RTE_FLOW_ITEM_TYPE_END; ++items) {
1089                 const struct tap_flow_items *token = NULL;
1090                 unsigned int i;
1091                 int err = 0;
1092
1093                 if (items->type == RTE_FLOW_ITEM_TYPE_VOID)
1094                         continue;
1095                 for (i = 0;
1096                      cur_item->items &&
1097                      cur_item->items[i] != RTE_FLOW_ITEM_TYPE_END;
1098                      ++i) {
1099                         if (cur_item->items[i] == items->type) {
1100                                 token = &tap_flow_items[items->type];
1101                                 break;
1102                         }
1103                 }
1104                 if (!token)
1105                         goto exit_item_not_supported;
1106                 cur_item = token;
1107                 err = tap_flow_item_validate(
1108                         items, cur_item->mask_sz,
1109                         (const uint8_t *)cur_item->mask,
1110                         (const uint8_t *)cur_item->default_mask);
1111                 if (err)
1112                         goto exit_item_not_supported;
1113                 if (flow && cur_item->convert) {
1114                         err = cur_item->convert(items, &data);
1115                         if (err)
1116                                 goto exit_item_not_supported;
1117                 }
1118         }
1119         if (flow) {
1120                 if (data.vlan) {
1121                         tap_nlattr_add16(&flow->msg.nh, TCA_FLOWER_KEY_ETH_TYPE,
1122                                      htons(ETH_P_8021Q));
1123                         tap_nlattr_add16(&flow->msg.nh,
1124                                      TCA_FLOWER_KEY_VLAN_ETH_TYPE,
1125                                      data.eth_type ?
1126                                      data.eth_type : htons(ETH_P_ALL));
1127                 } else if (data.eth_type) {
1128                         tap_nlattr_add16(&flow->msg.nh, TCA_FLOWER_KEY_ETH_TYPE,
1129                                      data.eth_type);
1130                 }
1131         }
1132         if (mirred && flow) {
1133                 struct action_data adata = {
1134                         .id = "mirred",
1135                         .mirred = {
1136                                 .eaction = mirred,
1137                         },
1138                 };
1139
1140                 /*
1141                  * If attr->egress && mirred, then this is a special
1142                  * case where the rule must be applied on the tap, to
1143                  * redirect packets coming from the DPDK App, out
1144                  * through the remote netdevice.
1145                  */
1146                 adata.mirred.ifindex = attr->ingress ? pmd->if_index :
1147                         pmd->remote_if_index;
1148                 if (mirred == TCA_EGRESS_MIRROR)
1149                         adata.mirred.action = TC_ACT_PIPE;
1150                 else
1151                         adata.mirred.action = TC_ACT_STOLEN;
1152                 if (add_actions(flow, 1, &adata, TCA_FLOWER_ACT) < 0)
1153                         goto exit_action_not_supported;
1154                 else
1155                         goto end;
1156         }
1157 actions:
1158         for (; actions->type != RTE_FLOW_ACTION_TYPE_END; ++actions) {
1159                 int err = 0;
1160
1161                 if (actions->type == RTE_FLOW_ACTION_TYPE_VOID) {
1162                         continue;
1163                 } else if (actions->type == RTE_FLOW_ACTION_TYPE_DROP) {
1164                         if (action)
1165                                 goto exit_action_not_supported;
1166                         action = 1;
1167                         if (flow) {
1168                                 struct action_data adata = {
1169                                         .id = "gact",
1170                                         .gact = {
1171                                                 .action = TC_ACT_SHOT,
1172                                         },
1173                                 };
1174
1175                                 err = add_actions(flow, 1, &adata,
1176                                                   TCA_FLOWER_ACT);
1177                         }
1178                 } else if (actions->type == RTE_FLOW_ACTION_TYPE_PASSTHRU) {
1179                         if (action)
1180                                 goto exit_action_not_supported;
1181                         action = 1;
1182                         if (flow) {
1183                                 struct action_data adata = {
1184                                         .id = "gact",
1185                                         .gact = {
1186                                                 /* continue */
1187                                                 .action = TC_ACT_UNSPEC,
1188                                         },
1189                                 };
1190
1191                                 err = add_actions(flow, 1, &adata,
1192                                                   TCA_FLOWER_ACT);
1193                         }
1194                 } else if (actions->type == RTE_FLOW_ACTION_TYPE_QUEUE) {
1195                         const struct rte_flow_action_queue *queue =
1196                                 (const struct rte_flow_action_queue *)
1197                                 actions->conf;
1198
1199                         if (action)
1200                                 goto exit_action_not_supported;
1201                         action = 1;
1202                         if (!queue ||
1203                             (queue->index > pmd->dev->data->nb_rx_queues - 1))
1204                                 goto exit_action_not_supported;
1205                         if (flow) {
1206                                 struct action_data adata = {
1207                                         .id = "skbedit",
1208                                         .skbedit = {
1209                                                 .skbedit = {
1210                                                         .action = TC_ACT_PIPE,
1211                                                 },
1212                                                 .queue = queue->index,
1213                                         },
1214                                 };
1215
1216                                 err = add_actions(flow, 1, &adata,
1217                                         TCA_FLOWER_ACT);
1218                         }
1219                 } else if (actions->type == RTE_FLOW_ACTION_TYPE_RSS) {
1220                         const struct rte_flow_action_rss *rss =
1221                                 (const struct rte_flow_action_rss *)
1222                                 actions->conf;
1223
1224                         if (action++)
1225                                 goto exit_action_not_supported;
1226
1227                         if (!pmd->rss_enabled) {
1228                                 err = rss_enable(pmd, attr, error);
1229                                 if (err)
1230                                         goto exit_action_not_supported;
1231                         }
1232                         if (flow)
1233                                 err = rss_add_actions(flow, pmd, rss, error);
1234                 } else {
1235                         goto exit_action_not_supported;
1236                 }
1237                 if (err)
1238                         goto exit_action_not_supported;
1239         }
1240         /* When fate is unknown, drop traffic. */
1241         if (!action) {
1242                 static const struct rte_flow_action drop[] = {
1243                         { .type = RTE_FLOW_ACTION_TYPE_DROP, },
1244                         { .type = RTE_FLOW_ACTION_TYPE_END, },
1245                 };
1246
1247                 actions = drop;
1248                 goto actions;
1249         }
1250 end:
1251         if (flow)
1252                 tap_nlattr_nested_finish(&flow->msg); /* nested TCA_OPTIONS */
1253         return 0;
1254 exit_item_not_supported:
1255         rte_flow_error_set(error, ENOTSUP, RTE_FLOW_ERROR_TYPE_ITEM,
1256                            items, "item not supported");
1257         return -rte_errno;
1258 exit_action_not_supported:
1259         rte_flow_error_set(error, ENOTSUP, RTE_FLOW_ERROR_TYPE_ACTION,
1260                            actions, "action not supported");
1261         return -rte_errno;
1262 }
1263
1264
1265
1266 /**
1267  * Validate a flow.
1268  *
1269  * @see rte_flow_validate()
1270  * @see rte_flow_ops
1271  */
1272 static int
1273 tap_flow_validate(struct rte_eth_dev *dev,
1274                   const struct rte_flow_attr *attr,
1275                   const struct rte_flow_item items[],
1276                   const struct rte_flow_action actions[],
1277                   struct rte_flow_error *error)
1278 {
1279         struct pmd_internals *pmd = dev->data->dev_private;
1280
1281         return priv_flow_process(pmd, attr, items, actions, error, NULL, 0);
1282 }
1283
1284 /**
1285  * Set a unique handle in a flow.
1286  *
1287  * The kernel supports TC rules with equal priority, as long as they use the
1288  * same matching fields (e.g.: dst mac and ipv4) with different values (and
1289  * full mask to ensure no collision is possible).
1290  * In those rules, the handle (uint32_t) is the part that would identify
1291  * specifically each rule.
1292  *
1293  * On 32-bit architectures, the handle can simply be the flow's pointer address.
1294  * On 64-bit architectures, we rely on jhash(flow) to find a (sufficiently)
1295  * unique handle.
1296  *
1297  * @param[in, out] flow
1298  *   The flow that needs its handle set.
1299  */
1300 static void
1301 tap_flow_set_handle(struct rte_flow *flow)
1302 {
1303         union {
1304                 struct rte_flow *flow;
1305                 const void *key;
1306         } tmp;
1307         uint32_t handle = 0;
1308
1309         tmp.flow = flow;
1310
1311         if (sizeof(flow) > 4)
1312                 handle = rte_jhash(tmp.key, sizeof(flow), 1);
1313         else
1314                 handle = (uintptr_t)flow;
1315         /* must be at least 1 to avoid letting the kernel choose one for us */
1316         if (!handle)
1317                 handle = 1;
1318         flow->msg.t.tcm_handle = handle;
1319 }
1320
1321 /**
1322  * Free the flow opened file descriptors and allocated memory
1323  *
1324  * @param[in] flow
1325  *   Pointer to the flow to free
1326  *
1327  */
1328 static void
1329 tap_flow_free(struct pmd_internals *pmd, struct rte_flow *flow)
1330 {
1331         int i;
1332
1333         if (!flow)
1334                 return;
1335
1336         if (pmd->rss_enabled) {
1337                 /* Close flow BPF file descriptors */
1338                 for (i = 0; i < SEC_MAX; i++)
1339                         if (flow->bpf_fd[i] != 0) {
1340                                 close(flow->bpf_fd[i]);
1341                                 flow->bpf_fd[i] = 0;
1342                         }
1343
1344                 /* Release the map key for this RSS rule */
1345                 bpf_rss_key(KEY_CMD_RELEASE, &flow->key_idx);
1346                 flow->key_idx = 0;
1347         }
1348
1349         /* Free flow allocated memory */
1350         rte_free(flow);
1351 }
1352
1353 /**
1354  * Create a flow.
1355  *
1356  * @see rte_flow_create()
1357  * @see rte_flow_ops
1358  */
1359 static struct rte_flow *
1360 tap_flow_create(struct rte_eth_dev *dev,
1361                 const struct rte_flow_attr *attr,
1362                 const struct rte_flow_item items[],
1363                 const struct rte_flow_action actions[],
1364                 struct rte_flow_error *error)
1365 {
1366         struct pmd_internals *pmd = dev->data->dev_private;
1367         struct rte_flow *remote_flow = NULL;
1368         struct rte_flow *flow = NULL;
1369         struct nlmsg *msg = NULL;
1370         int err;
1371
1372         if (!pmd->if_index) {
1373                 rte_flow_error_set(error, ENOTSUP, RTE_FLOW_ERROR_TYPE_HANDLE,
1374                                    NULL,
1375                                    "can't create rule, ifindex not found");
1376                 goto fail;
1377         }
1378         /*
1379          * No rules configured through standard rte_flow should be set on the
1380          * priorities used by implicit rules.
1381          */
1382         if ((attr->group == MAX_GROUP) &&
1383             attr->priority > (MAX_PRIORITY - TAP_REMOTE_MAX_IDX)) {
1384                 rte_flow_error_set(
1385                         error, ENOTSUP, RTE_FLOW_ERROR_TYPE_ATTR_PRIORITY,
1386                         NULL, "priority value too big");
1387                 goto fail;
1388         }
1389         flow = rte_zmalloc(__func__, sizeof(struct rte_flow), 0);
1390         if (!flow) {
1391                 rte_flow_error_set(error, ENOMEM, RTE_FLOW_ERROR_TYPE_HANDLE,
1392                                    NULL, "cannot allocate memory for rte_flow");
1393                 goto fail;
1394         }
1395         msg = &flow->msg;
1396         tc_init_msg(msg, pmd->if_index, RTM_NEWTFILTER,
1397                     NLM_F_REQUEST | NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE);
1398         msg->t.tcm_info = TC_H_MAKE(0, htons(ETH_P_ALL));
1399         tap_flow_set_handle(flow);
1400         if (priv_flow_process(pmd, attr, items, actions, error, flow, 0))
1401                 goto fail;
1402         err = tap_nl_send(pmd->nlsk_fd, &msg->nh);
1403         if (err < 0) {
1404                 rte_flow_error_set(error, ENOTSUP, RTE_FLOW_ERROR_TYPE_HANDLE,
1405                                    NULL, "couldn't send request to kernel");
1406                 goto fail;
1407         }
1408         err = tap_nl_recv_ack(pmd->nlsk_fd);
1409         if (err < 0) {
1410                 TAP_LOG(ERR,
1411                         "Kernel refused TC filter rule creation (%d): %s",
1412                         errno, strerror(errno));
1413                 rte_flow_error_set(error, EEXIST, RTE_FLOW_ERROR_TYPE_HANDLE,
1414                                    NULL,
1415                                    "overlapping rules or Kernel too old for flower support");
1416                 goto fail;
1417         }
1418         LIST_INSERT_HEAD(&pmd->flows, flow, next);
1419         /**
1420          * If a remote device is configured, a TC rule with identical items for
1421          * matching must be set on that device, with a single action: redirect
1422          * to the local pmd->if_index.
1423          */
1424         if (pmd->remote_if_index) {
1425                 remote_flow = rte_zmalloc(__func__, sizeof(struct rte_flow), 0);
1426                 if (!remote_flow) {
1427                         rte_flow_error_set(
1428                                 error, ENOMEM, RTE_FLOW_ERROR_TYPE_HANDLE, NULL,
1429                                 "cannot allocate memory for rte_flow");
1430                         goto fail;
1431                 }
1432                 msg = &remote_flow->msg;
1433                 /* set the rule if_index for the remote netdevice */
1434                 tc_init_msg(
1435                         msg, pmd->remote_if_index, RTM_NEWTFILTER,
1436                         NLM_F_REQUEST | NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE);
1437                 msg->t.tcm_info = TC_H_MAKE(0, htons(ETH_P_ALL));
1438                 tap_flow_set_handle(remote_flow);
1439                 if (priv_flow_process(pmd, attr, items, NULL,
1440                                       error, remote_flow, TCA_EGRESS_REDIR)) {
1441                         rte_flow_error_set(
1442                                 error, ENOMEM, RTE_FLOW_ERROR_TYPE_HANDLE,
1443                                 NULL, "rte flow rule validation failed");
1444                         goto fail;
1445                 }
1446                 err = tap_nl_send(pmd->nlsk_fd, &msg->nh);
1447                 if (err < 0) {
1448                         rte_flow_error_set(
1449                                 error, ENOMEM, RTE_FLOW_ERROR_TYPE_HANDLE,
1450                                 NULL, "Failure sending nl request");
1451                         goto fail;
1452                 }
1453                 err = tap_nl_recv_ack(pmd->nlsk_fd);
1454                 if (err < 0) {
1455                         TAP_LOG(ERR,
1456                                 "Kernel refused TC filter rule creation (%d): %s",
1457                                 errno, strerror(errno));
1458                         rte_flow_error_set(
1459                                 error, ENOMEM, RTE_FLOW_ERROR_TYPE_HANDLE,
1460                                 NULL,
1461                                 "overlapping rules or Kernel too old for flower support");
1462                         goto fail;
1463                 }
1464                 flow->remote_flow = remote_flow;
1465         }
1466         return flow;
1467 fail:
1468         if (remote_flow)
1469                 rte_free(remote_flow);
1470         if (flow)
1471                 tap_flow_free(pmd, flow);
1472         return NULL;
1473 }
1474
1475 /**
1476  * Destroy a flow using pointer to pmd_internal.
1477  *
1478  * @param[in, out] pmd
1479  *   Pointer to private structure.
1480  * @param[in] flow
1481  *   Pointer to the flow to destroy.
1482  * @param[in, out] error
1483  *   Pointer to the flow error handler
1484  *
1485  * @return 0 if the flow could be destroyed, -1 otherwise.
1486  */
1487 static int
1488 tap_flow_destroy_pmd(struct pmd_internals *pmd,
1489                      struct rte_flow *flow,
1490                      struct rte_flow_error *error)
1491 {
1492         struct rte_flow *remote_flow = flow->remote_flow;
1493         int ret = 0;
1494
1495         LIST_REMOVE(flow, next);
1496         flow->msg.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
1497         flow->msg.nh.nlmsg_type = RTM_DELTFILTER;
1498
1499         ret = tap_nl_send(pmd->nlsk_fd, &flow->msg.nh);
1500         if (ret < 0) {
1501                 rte_flow_error_set(error, ENOTSUP, RTE_FLOW_ERROR_TYPE_HANDLE,
1502                                    NULL, "couldn't send request to kernel");
1503                 goto end;
1504         }
1505         ret = tap_nl_recv_ack(pmd->nlsk_fd);
1506         /* If errno is ENOENT, the rule is already no longer in the kernel. */
1507         if (ret < 0 && errno == ENOENT)
1508                 ret = 0;
1509         if (ret < 0) {
1510                 TAP_LOG(ERR,
1511                         "Kernel refused TC filter rule deletion (%d): %s",
1512                         errno, strerror(errno));
1513                 rte_flow_error_set(
1514                         error, ENOTSUP, RTE_FLOW_ERROR_TYPE_HANDLE, NULL,
1515                         "couldn't receive kernel ack to our request");
1516                 goto end;
1517         }
1518
1519         if (remote_flow) {
1520                 remote_flow->msg.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
1521                 remote_flow->msg.nh.nlmsg_type = RTM_DELTFILTER;
1522
1523                 ret = tap_nl_send(pmd->nlsk_fd, &remote_flow->msg.nh);
1524                 if (ret < 0) {
1525                         rte_flow_error_set(
1526                                 error, ENOMEM, RTE_FLOW_ERROR_TYPE_HANDLE,
1527                                 NULL, "Failure sending nl request");
1528                         goto end;
1529                 }
1530                 ret = tap_nl_recv_ack(pmd->nlsk_fd);
1531                 if (ret < 0 && errno == ENOENT)
1532                         ret = 0;
1533                 if (ret < 0) {
1534                         TAP_LOG(ERR,
1535                                 "Kernel refused TC filter rule deletion (%d): %s",
1536                                 errno, strerror(errno));
1537                         rte_flow_error_set(
1538                                 error, ENOMEM, RTE_FLOW_ERROR_TYPE_HANDLE,
1539                                 NULL, "Failure trying to receive nl ack");
1540                         goto end;
1541                 }
1542         }
1543 end:
1544         if (remote_flow)
1545                 rte_free(remote_flow);
1546         tap_flow_free(pmd, flow);
1547         return ret;
1548 }
1549
1550 /**
1551  * Destroy a flow.
1552  *
1553  * @see rte_flow_destroy()
1554  * @see rte_flow_ops
1555  */
1556 static int
1557 tap_flow_destroy(struct rte_eth_dev *dev,
1558                  struct rte_flow *flow,
1559                  struct rte_flow_error *error)
1560 {
1561         struct pmd_internals *pmd = dev->data->dev_private;
1562
1563         return tap_flow_destroy_pmd(pmd, flow, error);
1564 }
1565
1566 /**
1567  * Enable/disable flow isolation.
1568  *
1569  * @see rte_flow_isolate()
1570  * @see rte_flow_ops
1571  */
1572 static int
1573 tap_flow_isolate(struct rte_eth_dev *dev,
1574                  int set,
1575                  struct rte_flow_error *error __rte_unused)
1576 {
1577         struct pmd_internals *pmd = dev->data->dev_private;
1578         struct pmd_process_private *process_private = dev->process_private;
1579
1580         /* normalize 'set' variable to contain 0 or 1 values */
1581         if (set)
1582                 set = 1;
1583         /* if already in the right isolation mode - nothing to do */
1584         if ((set ^ pmd->flow_isolate) == 0)
1585                 return 0;
1586         /* mark the isolation mode for tap_flow_implicit_create() */
1587         pmd->flow_isolate = set;
1588         /*
1589          * If netdevice is there, setup appropriate flow rules immediately.
1590          * Otherwise it will be set when bringing up the netdevice (tun_alloc).
1591          */
1592         if (!process_private->rxq_fds[0])
1593                 return 0;
1594         if (set) {
1595                 struct rte_flow *remote_flow;
1596
1597                 while (1) {
1598                         remote_flow = LIST_FIRST(&pmd->implicit_flows);
1599                         if (!remote_flow)
1600                                 break;
1601                         /*
1602                          * Remove all implicit rules on the remote.
1603                          * Keep the local rule to redirect packets on TX.
1604                          * Keep also the last implicit local rule: ISOLATE.
1605                          */
1606                         if (remote_flow->msg.t.tcm_ifindex == pmd->if_index)
1607                                 break;
1608                         if (tap_flow_destroy_pmd(pmd, remote_flow, NULL) < 0)
1609                                 goto error;
1610                 }
1611                 /* Switch the TC rule according to pmd->flow_isolate */
1612                 if (tap_flow_implicit_create(pmd, TAP_ISOLATE) == -1)
1613                         goto error;
1614         } else {
1615                 /* Switch the TC rule according to pmd->flow_isolate */
1616                 if (tap_flow_implicit_create(pmd, TAP_ISOLATE) == -1)
1617                         goto error;
1618                 if (!pmd->remote_if_index)
1619                         return 0;
1620                 if (tap_flow_implicit_create(pmd, TAP_REMOTE_TX) < 0)
1621                         goto error;
1622                 if (tap_flow_implicit_create(pmd, TAP_REMOTE_LOCAL_MAC) < 0)
1623                         goto error;
1624                 if (tap_flow_implicit_create(pmd, TAP_REMOTE_BROADCAST) < 0)
1625                         goto error;
1626                 if (tap_flow_implicit_create(pmd, TAP_REMOTE_BROADCASTV6) < 0)
1627                         goto error;
1628                 if (dev->data->promiscuous &&
1629                     tap_flow_implicit_create(pmd, TAP_REMOTE_PROMISC) < 0)
1630                         goto error;
1631                 if (dev->data->all_multicast &&
1632                     tap_flow_implicit_create(pmd, TAP_REMOTE_ALLMULTI) < 0)
1633                         goto error;
1634         }
1635         return 0;
1636 error:
1637         pmd->flow_isolate = 0;
1638         return rte_flow_error_set(
1639                 error, ENOTSUP, RTE_FLOW_ERROR_TYPE_UNSPECIFIED, NULL,
1640                 "TC rule creation failed");
1641 }
1642
1643 /**
1644  * Destroy all flows.
1645  *
1646  * @see rte_flow_flush()
1647  * @see rte_flow_ops
1648  */
1649 int
1650 tap_flow_flush(struct rte_eth_dev *dev, struct rte_flow_error *error)
1651 {
1652         struct pmd_internals *pmd = dev->data->dev_private;
1653         struct rte_flow *flow;
1654
1655         while (!LIST_EMPTY(&pmd->flows)) {
1656                 flow = LIST_FIRST(&pmd->flows);
1657                 if (tap_flow_destroy(dev, flow, error) < 0)
1658                         return -1;
1659         }
1660         return 0;
1661 }
1662
1663 /**
1664  * Add an implicit flow rule on the remote device to make sure traffic gets to
1665  * the tap netdevice from there.
1666  *
1667  * @param pmd
1668  *   Pointer to private structure.
1669  * @param[in] idx
1670  *   The idx in the implicit_rte_flows array specifying which rule to apply.
1671  *
1672  * @return -1 if the rule couldn't be applied, 0 otherwise.
1673  */
1674 int tap_flow_implicit_create(struct pmd_internals *pmd,
1675                              enum implicit_rule_index idx)
1676 {
1677         uint16_t flags = NLM_F_REQUEST | NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE;
1678         struct rte_flow_action *actions = implicit_rte_flows[idx].actions;
1679         struct rte_flow_action isolate_actions[2] = {
1680                 [1] = {
1681                         .type = RTE_FLOW_ACTION_TYPE_END,
1682                 },
1683         };
1684         struct rte_flow_item *items = implicit_rte_flows[idx].items;
1685         struct rte_flow_attr *attr = &implicit_rte_flows[idx].attr;
1686         struct rte_flow_item_eth eth_local = { .type = 0 };
1687         uint16_t if_index = pmd->remote_if_index;
1688         struct rte_flow *remote_flow = NULL;
1689         struct nlmsg *msg = NULL;
1690         int err = 0;
1691         struct rte_flow_item items_local[2] = {
1692                 [0] = {
1693                         .type = items[0].type,
1694                         .spec = &eth_local,
1695                         .mask = items[0].mask,
1696                 },
1697                 [1] = {
1698                         .type = items[1].type,
1699                 }
1700         };
1701
1702         remote_flow = rte_zmalloc(__func__, sizeof(struct rte_flow), 0);
1703         if (!remote_flow) {
1704                 TAP_LOG(ERR, "Cannot allocate memory for rte_flow");
1705                 goto fail;
1706         }
1707         msg = &remote_flow->msg;
1708         if (idx == TAP_REMOTE_TX) {
1709                 if_index = pmd->if_index;
1710         } else if (idx == TAP_ISOLATE) {
1711                 if_index = pmd->if_index;
1712                 /* Don't be exclusive for this rule, it can be changed later. */
1713                 flags = NLM_F_REQUEST | NLM_F_ACK | NLM_F_CREATE;
1714                 isolate_actions[0].type = pmd->flow_isolate ?
1715                         RTE_FLOW_ACTION_TYPE_DROP :
1716                         RTE_FLOW_ACTION_TYPE_PASSTHRU;
1717                 actions = isolate_actions;
1718         } else if (idx == TAP_REMOTE_LOCAL_MAC) {
1719                 /*
1720                  * eth addr couldn't be set in implicit_rte_flows[] as it is not
1721                  * known at compile time.
1722                  */
1723                 memcpy(&eth_local.dst, &pmd->eth_addr, sizeof(pmd->eth_addr));
1724                 items = items_local;
1725         }
1726         tc_init_msg(msg, if_index, RTM_NEWTFILTER, flags);
1727         msg->t.tcm_info = TC_H_MAKE(0, htons(ETH_P_ALL));
1728         /*
1729          * The ISOLATE rule is always present and must have a static handle, as
1730          * the action is changed whether the feature is enabled (DROP) or
1731          * disabled (PASSTHRU).
1732          * There is just one REMOTE_PROMISCUOUS rule in all cases. It should
1733          * have a static handle such that adding it twice will fail with EEXIST
1734          * with any kernel version. Remark: old kernels may falsely accept the
1735          * same REMOTE_PROMISCUOUS rules if they had different handles.
1736          */
1737         if (idx == TAP_ISOLATE)
1738                 remote_flow->msg.t.tcm_handle = ISOLATE_HANDLE;
1739         else if (idx == TAP_REMOTE_PROMISC)
1740                 remote_flow->msg.t.tcm_handle = REMOTE_PROMISCUOUS_HANDLE;
1741         else
1742                 tap_flow_set_handle(remote_flow);
1743         if (priv_flow_process(pmd, attr, items, actions, NULL,
1744                               remote_flow, implicit_rte_flows[idx].mirred)) {
1745                 TAP_LOG(ERR, "rte flow rule validation failed");
1746                 goto fail;
1747         }
1748         err = tap_nl_send(pmd->nlsk_fd, &msg->nh);
1749         if (err < 0) {
1750                 TAP_LOG(ERR, "Failure sending nl request");
1751                 goto fail;
1752         }
1753         err = tap_nl_recv_ack(pmd->nlsk_fd);
1754         if (err < 0) {
1755                 /* Silently ignore re-entering existing rule */
1756                 if (errno == EEXIST)
1757                         goto success;
1758                 TAP_LOG(ERR,
1759                         "Kernel refused TC filter rule creation (%d): %s",
1760                         errno, strerror(errno));
1761                 goto fail;
1762         }
1763         LIST_INSERT_HEAD(&pmd->implicit_flows, remote_flow, next);
1764 success:
1765         return 0;
1766 fail:
1767         if (remote_flow)
1768                 rte_free(remote_flow);
1769         return -1;
1770 }
1771
1772 /**
1773  * Remove specific implicit flow rule on the remote device.
1774  *
1775  * @param[in, out] pmd
1776  *   Pointer to private structure.
1777  * @param[in] idx
1778  *   The idx in the implicit_rte_flows array specifying which rule to remove.
1779  *
1780  * @return -1 if one of the implicit rules couldn't be created, 0 otherwise.
1781  */
1782 int tap_flow_implicit_destroy(struct pmd_internals *pmd,
1783                               enum implicit_rule_index idx)
1784 {
1785         struct rte_flow *remote_flow;
1786         int cur_prio = -1;
1787         int idx_prio = implicit_rte_flows[idx].attr.priority + PRIORITY_OFFSET;
1788
1789         for (remote_flow = LIST_FIRST(&pmd->implicit_flows);
1790              remote_flow;
1791              remote_flow = LIST_NEXT(remote_flow, next)) {
1792                 cur_prio = (remote_flow->msg.t.tcm_info >> 16) & PRIORITY_MASK;
1793                 if (cur_prio != idx_prio)
1794                         continue;
1795                 return tap_flow_destroy_pmd(pmd, remote_flow, NULL);
1796         }
1797         return 0;
1798 }
1799
1800 /**
1801  * Destroy all implicit flows.
1802  *
1803  * @see rte_flow_flush()
1804  */
1805 int
1806 tap_flow_implicit_flush(struct pmd_internals *pmd, struct rte_flow_error *error)
1807 {
1808         struct rte_flow *remote_flow;
1809
1810         while (!LIST_EMPTY(&pmd->implicit_flows)) {
1811                 remote_flow = LIST_FIRST(&pmd->implicit_flows);
1812                 if (tap_flow_destroy_pmd(pmd, remote_flow, error) < 0)
1813                         return -1;
1814         }
1815         return 0;
1816 }
1817
1818 #define MAX_RSS_KEYS 256
1819 #define KEY_IDX_OFFSET (3 * MAX_RSS_KEYS)
1820 #define SEC_NAME_CLS_Q "cls_q"
1821
1822 static const char *sec_name[SEC_MAX] = {
1823         [SEC_L3_L4] = "l3_l4",
1824 };
1825
1826 /**
1827  * Enable RSS on tap: create TC rules for queuing.
1828  *
1829  * @param[in, out] pmd
1830  *   Pointer to private structure.
1831  *
1832  * @param[in] attr
1833  *   Pointer to rte_flow to get flow group
1834  *
1835  * @param[out] error
1836  *   Pointer to error reporting if not NULL.
1837  *
1838  * @return 0 on success, negative value on failure.
1839  */
1840 static int rss_enable(struct pmd_internals *pmd,
1841                         const struct rte_flow_attr *attr,
1842                         struct rte_flow_error *error)
1843 {
1844         struct rte_flow *rss_flow = NULL;
1845         struct nlmsg *msg = NULL;
1846         /* 4096 is the maximum number of instructions for a BPF program */
1847         char annotation[64];
1848         int i;
1849         int err = 0;
1850
1851         /* unlimit locked memory */
1852         struct rlimit memlock_limit = {
1853                 .rlim_cur = RLIM_INFINITY,
1854                 .rlim_max = RLIM_INFINITY,
1855         };
1856         setrlimit(RLIMIT_MEMLOCK, &memlock_limit);
1857
1858          /* Get a new map key for a new RSS rule */
1859         err = bpf_rss_key(KEY_CMD_INIT, NULL);
1860         if (err < 0) {
1861                 rte_flow_error_set(
1862                         error, EINVAL, RTE_FLOW_ERROR_TYPE_HANDLE, NULL,
1863                         "Failed to initialize BPF RSS keys");
1864
1865                 return -1;
1866         }
1867
1868         /*
1869          *  Create BPF RSS MAP
1870          */
1871         pmd->map_fd = tap_flow_bpf_rss_map_create(sizeof(__u32), /* key size */
1872                                 sizeof(struct rss_key),
1873                                 MAX_RSS_KEYS);
1874         if (pmd->map_fd < 0) {
1875                 TAP_LOG(ERR,
1876                         "Failed to create BPF map (%d): %s",
1877                                 errno, strerror(errno));
1878                 rte_flow_error_set(
1879                         error, ENOTSUP, RTE_FLOW_ERROR_TYPE_HANDLE, NULL,
1880                         "Kernel too old or not configured "
1881                         "to support BPF maps");
1882
1883                 return -ENOTSUP;
1884         }
1885
1886         /*
1887          * Add a rule per queue to match reclassified packets and direct them to
1888          * the correct queue.
1889          */
1890         for (i = 0; i < pmd->dev->data->nb_rx_queues; i++) {
1891                 pmd->bpf_fd[i] = tap_flow_bpf_cls_q(i);
1892                 if (pmd->bpf_fd[i] < 0) {
1893                         TAP_LOG(ERR,
1894                                 "Failed to load BPF section %s for queue %d",
1895                                 SEC_NAME_CLS_Q, i);
1896                         rte_flow_error_set(
1897                                 error, ENOTSUP, RTE_FLOW_ERROR_TYPE_HANDLE,
1898                                 NULL,
1899                                 "Kernel too old or not configured "
1900                                 "to support BPF programs loading");
1901
1902                         return -ENOTSUP;
1903                 }
1904
1905                 rss_flow = rte_zmalloc(__func__, sizeof(struct rte_flow), 0);
1906                 if (!rss_flow) {
1907                         TAP_LOG(ERR,
1908                                 "Cannot allocate memory for rte_flow");
1909                         return -1;
1910                 }
1911                 msg = &rss_flow->msg;
1912                 tc_init_msg(msg, pmd->if_index, RTM_NEWTFILTER, NLM_F_REQUEST |
1913                             NLM_F_ACK | NLM_F_EXCL | NLM_F_CREATE);
1914                 msg->t.tcm_info = TC_H_MAKE(0, htons(ETH_P_ALL));
1915                 tap_flow_set_handle(rss_flow);
1916                 uint16_t group = attr->group << GROUP_SHIFT;
1917                 uint16_t prio = group | (i + PRIORITY_OFFSET);
1918                 msg->t.tcm_info = TC_H_MAKE(prio << 16, msg->t.tcm_info);
1919                 msg->t.tcm_parent = TC_H_MAKE(MULTIQ_MAJOR_HANDLE, 0);
1920
1921                 tap_nlattr_add(&msg->nh, TCA_KIND, sizeof("bpf"), "bpf");
1922                 if (tap_nlattr_nested_start(msg, TCA_OPTIONS) < 0)
1923                         return -1;
1924                 tap_nlattr_add32(&msg->nh, TCA_BPF_FD, pmd->bpf_fd[i]);
1925                 snprintf(annotation, sizeof(annotation), "[%s%d]",
1926                         SEC_NAME_CLS_Q, i);
1927                 tap_nlattr_add(&msg->nh, TCA_BPF_NAME, strlen(annotation) + 1,
1928                            annotation);
1929                 /* Actions */
1930                 {
1931                         struct action_data adata = {
1932                                 .id = "skbedit",
1933                                 .skbedit = {
1934                                         .skbedit = {
1935                                                 .action = TC_ACT_PIPE,
1936                                         },
1937                                         .queue = i,
1938                                 },
1939                         };
1940                         if (add_actions(rss_flow, 1, &adata, TCA_BPF_ACT) < 0)
1941                                 return -1;
1942                 }
1943                 tap_nlattr_nested_finish(msg); /* nested TCA_OPTIONS */
1944
1945                 /* Netlink message is now ready to be sent */
1946                 if (tap_nl_send(pmd->nlsk_fd, &msg->nh) < 0)
1947                         return -1;
1948                 err = tap_nl_recv_ack(pmd->nlsk_fd);
1949                 if (err < 0) {
1950                         TAP_LOG(ERR,
1951                                 "Kernel refused TC filter rule creation (%d): %s",
1952                                 errno, strerror(errno));
1953                         return err;
1954                 }
1955                 LIST_INSERT_HEAD(&pmd->rss_flows, rss_flow, next);
1956         }
1957
1958         pmd->rss_enabled = 1;
1959         return err;
1960 }
1961
1962 /**
1963  * Manage bpf RSS keys repository with operations: init, get, release
1964  *
1965  * @param[in] cmd
1966  *   Command on RSS keys: init, get, release
1967  *
1968  * @param[in, out] key_idx
1969  *   Pointer to RSS Key index (out for get command, in for release command)
1970  *
1971  * @return -1 if couldn't get, release or init the RSS keys, 0 otherwise.
1972  */
1973 static int bpf_rss_key(enum bpf_rss_key_e cmd, __u32 *key_idx)
1974 {
1975         __u32 i;
1976         int err = 0;
1977         static __u32 num_used_keys;
1978         static __u32 rss_keys[MAX_RSS_KEYS] = {KEY_STAT_UNSPEC};
1979         static __u32 rss_keys_initialized;
1980         __u32 key;
1981
1982         switch (cmd) {
1983         case KEY_CMD_GET:
1984                 if (!rss_keys_initialized) {
1985                         err = -1;
1986                         break;
1987                 }
1988
1989                 if (num_used_keys == RTE_DIM(rss_keys)) {
1990                         err = -1;
1991                         break;
1992                 }
1993
1994                 *key_idx = num_used_keys % RTE_DIM(rss_keys);
1995                 while (rss_keys[*key_idx] == KEY_STAT_USED)
1996                         *key_idx = (*key_idx + 1) % RTE_DIM(rss_keys);
1997
1998                 rss_keys[*key_idx] = KEY_STAT_USED;
1999
2000                 /*
2001                  * Add an offset to key_idx in order to handle a case of
2002                  * RSS and non RSS flows mixture.
2003                  * If a non RSS flow is destroyed it has an eBPF map
2004                  * index 0 (initialized on flow creation) and might
2005                  * unintentionally remove RSS entry 0 from eBPF map.
2006                  * To avoid this issue, add an offset to the real index
2007                  * during a KEY_CMD_GET operation and subtract this offset
2008                  * during a KEY_CMD_RELEASE operation in order to restore
2009                  * the real index.
2010                  */
2011                 *key_idx += KEY_IDX_OFFSET;
2012                 num_used_keys++;
2013         break;
2014
2015         case KEY_CMD_RELEASE:
2016                 if (!rss_keys_initialized)
2017                         break;
2018
2019                 /*
2020                  * Subtract offest to restore real key index
2021                  * If a non RSS flow is falsely trying to release map
2022                  * entry 0 - the offset subtraction will calculate the real
2023                  * map index as an out-of-range value and the release operation
2024                  * will be silently ignored.
2025                  */
2026                 key = *key_idx - KEY_IDX_OFFSET;
2027                 if (key >= RTE_DIM(rss_keys))
2028                         break;
2029
2030                 if (rss_keys[key] == KEY_STAT_USED) {
2031                         rss_keys[key] = KEY_STAT_AVAILABLE;
2032                         num_used_keys--;
2033                 }
2034         break;
2035
2036         case KEY_CMD_INIT:
2037                 for (i = 0; i < RTE_DIM(rss_keys); i++)
2038                         rss_keys[i] = KEY_STAT_AVAILABLE;
2039
2040                 rss_keys_initialized = 1;
2041                 num_used_keys = 0;
2042         break;
2043
2044         case KEY_CMD_DEINIT:
2045                 for (i = 0; i < RTE_DIM(rss_keys); i++)
2046                         rss_keys[i] = KEY_STAT_UNSPEC;
2047
2048                 rss_keys_initialized = 0;
2049                 num_used_keys = 0;
2050         break;
2051
2052         default:
2053                 break;
2054         }
2055
2056         return err;
2057 }
2058
2059 /**
2060  * Add RSS hash calculations and queue selection
2061  *
2062  * @param[in, out] pmd
2063  *   Pointer to internal structure. Used to set/get RSS map fd
2064  *
2065  * @param[in] rss
2066  *   Pointer to RSS flow actions
2067  *
2068  * @param[out] error
2069  *   Pointer to error reporting if not NULL.
2070  *
2071  * @return 0 on success, negative value on failure
2072  */
2073 static int rss_add_actions(struct rte_flow *flow, struct pmd_internals *pmd,
2074                            const struct rte_flow_action_rss *rss,
2075                            struct rte_flow_error *error)
2076 {
2077         /* 4096 is the maximum number of instructions for a BPF program */
2078         unsigned int i;
2079         int err;
2080         struct rss_key rss_entry = { .hash_fields = 0,
2081                                      .key_size = 0 };
2082
2083         /* Check supported RSS features */
2084         if (rss->func != RTE_ETH_HASH_FUNCTION_DEFAULT)
2085                 return rte_flow_error_set
2086                         (error, ENOTSUP, RTE_FLOW_ERROR_TYPE_UNSPECIFIED, NULL,
2087                          "non-default RSS hash functions are not supported");
2088         if (rss->level)
2089                 return rte_flow_error_set
2090                         (error, ENOTSUP, RTE_FLOW_ERROR_TYPE_UNSPECIFIED, NULL,
2091                          "a nonzero RSS encapsulation level is not supported");
2092
2093         /* Get a new map key for a new RSS rule */
2094         err = bpf_rss_key(KEY_CMD_GET, &flow->key_idx);
2095         if (err < 0) {
2096                 rte_flow_error_set(
2097                         error, EINVAL, RTE_FLOW_ERROR_TYPE_HANDLE, NULL,
2098                         "Failed to get BPF RSS key");
2099
2100                 return -1;
2101         }
2102
2103         /* Update RSS map entry with queues */
2104         rss_entry.nb_queues = rss->queue_num;
2105         for (i = 0; i < rss->queue_num; i++)
2106                 rss_entry.queues[i] = rss->queue[i];
2107         rss_entry.hash_fields =
2108                 (1 << HASH_FIELD_IPV4_L3_L4) | (1 << HASH_FIELD_IPV6_L3_L4);
2109
2110         /* Add this RSS entry to map */
2111         err = tap_flow_bpf_update_rss_elem(pmd->map_fd,
2112                                 &flow->key_idx, &rss_entry);
2113
2114         if (err) {
2115                 TAP_LOG(ERR,
2116                         "Failed to update BPF map entry #%u (%d): %s",
2117                         flow->key_idx, errno, strerror(errno));
2118                 rte_flow_error_set(
2119                         error, ENOTSUP, RTE_FLOW_ERROR_TYPE_HANDLE, NULL,
2120                         "Kernel too old or not configured "
2121                         "to support BPF maps updates");
2122
2123                 return -ENOTSUP;
2124         }
2125
2126
2127         /*
2128          * Load bpf rules to calculate hash for this key_idx
2129          */
2130
2131         flow->bpf_fd[SEC_L3_L4] =
2132                 tap_flow_bpf_calc_l3_l4_hash(flow->key_idx, pmd->map_fd);
2133         if (flow->bpf_fd[SEC_L3_L4] < 0) {
2134                 TAP_LOG(ERR,
2135                         "Failed to load BPF section %s (%d): %s",
2136                                 sec_name[SEC_L3_L4], errno, strerror(errno));
2137                 rte_flow_error_set(
2138                         error, ENOTSUP, RTE_FLOW_ERROR_TYPE_HANDLE, NULL,
2139                         "Kernel too old or not configured "
2140                         "to support BPF program loading");
2141
2142                 return -ENOTSUP;
2143         }
2144
2145         /* Actions */
2146         {
2147                 struct action_data adata[] = {
2148                         {
2149                                 .id = "bpf",
2150                                 .bpf = {
2151                                         .bpf_fd = flow->bpf_fd[SEC_L3_L4],
2152                                         .annotation = sec_name[SEC_L3_L4],
2153                                         .bpf = {
2154                                                 .action = TC_ACT_PIPE,
2155                                         },
2156                                 },
2157                         },
2158                 };
2159
2160                 if (add_actions(flow, RTE_DIM(adata), adata,
2161                         TCA_FLOWER_ACT) < 0)
2162                         return -1;
2163         }
2164
2165         return 0;
2166 }
2167
2168 /**
2169  * Get rte_flow operations.
2170  *
2171  * @param dev
2172  *   Pointer to Ethernet device structure.
2173  * @param ops
2174  *   Pointer to operation-specific structure.
2175  *
2176  * @return
2177  *   0 on success, negative errno value on failure.
2178  */
2179 int
2180 tap_dev_flow_ops_get(struct rte_eth_dev *dev __rte_unused,
2181                      const struct rte_flow_ops **ops)
2182 {
2183         *ops = &tap_flow_ops;
2184         return 0;
2185 }