1// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) 2 3/* 4 * AF_XDP user-space access library. 5 * 6 * Copyright(c) 2018 - 2019 Intel Corporation. 7 * 8 * Author(s): Magnus Karlsson <magnus.karlsson@intel.com> 9 */ 10 11#include <errno.h> 12#include <stdlib.h> 13#include <string.h> 14#include <unistd.h> 15#include <arpa/inet.h> 16#include <asm/barrier.h> 17#include <linux/compiler.h> 18#include <linux/ethtool.h> 19#include <linux/filter.h> 20#include <linux/if_ether.h> 21#include <linux/if_link.h> 22#include <linux/if_packet.h> 23#include <linux/if_xdp.h> 24#include <linux/kernel.h> 25#include <linux/list.h> 26#include <linux/netlink.h> 27#include <linux/rtnetlink.h> 28#include <linux/sockios.h> 29#include <net/if.h> 30#include <sys/ioctl.h> 31#include <sys/mman.h> 32#include <sys/socket.h> 33#include <sys/types.h> 34 35#include <bpf/bpf.h> 36#include <bpf/libbpf.h> 37#include "xsk.h" 38#include "bpf_util.h" 39 40#ifndef SOL_XDP 41 #define SOL_XDP 283 42#endif 43 44#ifndef AF_XDP 45 #define AF_XDP 44 46#endif 47 48#ifndef PF_XDP 49 #define PF_XDP AF_XDP 50#endif 51 52#define pr_warn(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__) 53 54#define XSKMAP_SIZE 1 55 56struct xsk_umem { 57 struct xsk_ring_prod *fill_save; 58 struct xsk_ring_cons *comp_save; 59 char *umem_area; 60 struct xsk_umem_config config; 61 int fd; 62 int refcount; 63 struct list_head ctx_list; 64 bool rx_ring_setup_done; 65 bool tx_ring_setup_done; 66}; 67 68struct xsk_ctx { 69 struct xsk_ring_prod *fill; 70 struct xsk_ring_cons *comp; 71 __u32 queue_id; 72 struct xsk_umem *umem; 73 int refcount; 74 int ifindex; 75 struct list_head list; 76}; 77 78struct xsk_socket { 79 struct xsk_ring_cons *rx; 80 struct xsk_ring_prod *tx; 81 struct xsk_ctx *ctx; 82 struct xsk_socket_config config; 83 int fd; 84}; 85 86struct nl_mtu_req { 87 struct nlmsghdr nh; 88 struct ifinfomsg msg; 89 char buf[512]; 90}; 91 92int xsk_umem__fd(const struct xsk_umem *umem) 93{ 94 return umem ? umem->fd : -EINVAL; 95} 96 97int xsk_socket__fd(const struct xsk_socket *xsk) 98{ 99 return xsk ? xsk->fd : -EINVAL; 100} 101 102static bool xsk_page_aligned(void *buffer) 103{ 104 unsigned long addr = (unsigned long)buffer; 105 106 return !(addr & (getpagesize() - 1)); 107} 108 109static void xsk_set_umem_config(struct xsk_umem_config *cfg, 110 const struct xsk_umem_config *usr_cfg) 111{ 112 if (!usr_cfg) { 113 cfg->fill_size = XSK_RING_PROD__DEFAULT_NUM_DESCS; 114 cfg->comp_size = XSK_RING_CONS__DEFAULT_NUM_DESCS; 115 cfg->frame_size = XSK_UMEM__DEFAULT_FRAME_SIZE; 116 cfg->frame_headroom = XSK_UMEM__DEFAULT_FRAME_HEADROOM; 117 cfg->flags = XSK_UMEM__DEFAULT_FLAGS; 118 cfg->tx_metadata_len = 0; 119 return; 120 } 121 122 cfg->fill_size = usr_cfg->fill_size; 123 cfg->comp_size = usr_cfg->comp_size; 124 cfg->frame_size = usr_cfg->frame_size; 125 cfg->frame_headroom = usr_cfg->frame_headroom; 126 cfg->flags = usr_cfg->flags; 127 cfg->tx_metadata_len = usr_cfg->tx_metadata_len; 128} 129 130static int xsk_set_xdp_socket_config(struct xsk_socket_config *cfg, 131 const struct xsk_socket_config *usr_cfg) 132{ 133 if (!usr_cfg) { 134 cfg->rx_size = XSK_RING_CONS__DEFAULT_NUM_DESCS; 135 cfg->tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS; 136 cfg->bind_flags = 0; 137 return 0; 138 } 139 140 cfg->rx_size = usr_cfg->rx_size; 141 cfg->tx_size = usr_cfg->tx_size; 142 cfg->bind_flags = usr_cfg->bind_flags; 143 144 return 0; 145} 146 147static int xsk_get_mmap_offsets(int fd, struct xdp_mmap_offsets *off) 148{ 149 socklen_t optlen; 150 int err; 151 152 optlen = sizeof(*off); 153 err = getsockopt(fd, SOL_XDP, XDP_MMAP_OFFSETS, off, &optlen); 154 if (err) 155 return err; 156 157 if (optlen == sizeof(*off)) 158 return 0; 159 160 return -EINVAL; 161} 162 163static int xsk_create_umem_rings(struct xsk_umem *umem, int fd, 164 struct xsk_ring_prod *fill, 165 struct xsk_ring_cons *comp) 166{ 167 struct xdp_mmap_offsets off; 168 void *map; 169 int err; 170 171 err = setsockopt(fd, SOL_XDP, XDP_UMEM_FILL_RING, 172 &umem->config.fill_size, 173 sizeof(umem->config.fill_size)); 174 if (err) 175 return -errno; 176 177 err = setsockopt(fd, SOL_XDP, XDP_UMEM_COMPLETION_RING, 178 &umem->config.comp_size, 179 sizeof(umem->config.comp_size)); 180 if (err) 181 return -errno; 182 183 err = xsk_get_mmap_offsets(fd, &off); 184 if (err) 185 return -errno; 186 187 map = mmap(NULL, off.fr.desc + umem->config.fill_size * sizeof(__u64), 188 PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd, 189 XDP_UMEM_PGOFF_FILL_RING); 190 if (map == MAP_FAILED) 191 return -errno; 192 193 fill->mask = umem->config.fill_size - 1; 194 fill->size = umem->config.fill_size; 195 fill->producer = map + off.fr.producer; 196 fill->consumer = map + off.fr.consumer; 197 fill->flags = map + off.fr.flags; 198 fill->ring = map + off.fr.desc; 199 fill->cached_cons = umem->config.fill_size; 200 201 map = mmap(NULL, off.cr.desc + umem->config.comp_size * sizeof(__u64), 202 PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd, 203 XDP_UMEM_PGOFF_COMPLETION_RING); 204 if (map == MAP_FAILED) { 205 err = -errno; 206 goto out_mmap; 207 } 208 209 comp->mask = umem->config.comp_size - 1; 210 comp->size = umem->config.comp_size; 211 comp->producer = map + off.cr.producer; 212 comp->consumer = map + off.cr.consumer; 213 comp->flags = map + off.cr.flags; 214 comp->ring = map + off.cr.desc; 215 216 return 0; 217 218out_mmap: 219 munmap(map, off.fr.desc + umem->config.fill_size * sizeof(__u64)); 220 return err; 221} 222 223int xsk_umem__create(struct xsk_umem **umem_ptr, void *umem_area, 224 __u64 size, struct xsk_ring_prod *fill, 225 struct xsk_ring_cons *comp, 226 const struct xsk_umem_config *usr_config) 227{ 228 struct xdp_umem_reg mr; 229 struct xsk_umem *umem; 230 int err; 231 232 if (!umem_area || !umem_ptr || !fill || !comp) 233 return -EFAULT; 234 if (!size && !xsk_page_aligned(umem_area)) 235 return -EINVAL; 236 237 umem = calloc(1, sizeof(*umem)); 238 if (!umem) 239 return -ENOMEM; 240 241 umem->fd = socket(AF_XDP, SOCK_RAW | SOCK_CLOEXEC, 0); 242 if (umem->fd < 0) { 243 err = -errno; 244 goto out_umem_alloc; 245 } 246 247 umem->umem_area = umem_area; 248 INIT_LIST_HEAD(&umem->ctx_list); 249 xsk_set_umem_config(&umem->config, usr_config); 250 251 memset(&mr, 0, sizeof(mr)); 252 mr.addr = (uintptr_t)umem_area; 253 mr.len = size; 254 mr.chunk_size = umem->config.frame_size; 255 mr.headroom = umem->config.frame_headroom; 256 mr.flags = umem->config.flags; 257 mr.tx_metadata_len = umem->config.tx_metadata_len; 258 259 err = setsockopt(umem->fd, SOL_XDP, XDP_UMEM_REG, &mr, sizeof(mr)); 260 if (err) { 261 err = -errno; 262 goto out_socket; 263 } 264 265 err = xsk_create_umem_rings(umem, umem->fd, fill, comp); 266 if (err) 267 goto out_socket; 268 269 umem->fill_save = fill; 270 umem->comp_save = comp; 271 *umem_ptr = umem; 272 return 0; 273 274out_socket: 275 close(umem->fd); 276out_umem_alloc: 277 free(umem); 278 return err; 279} 280 281bool xsk_is_in_mode(u32 ifindex, int mode) 282{ 283 LIBBPF_OPTS(bpf_xdp_query_opts, opts); 284 int ret; 285 286 ret = bpf_xdp_query(ifindex, mode, &opts); 287 if (ret) { 288 printf("XDP mode query returned error %s\n", strerror(errno)); 289 return false; 290 } 291 292 if (mode == XDP_FLAGS_DRV_MODE) 293 return opts.attach_mode == XDP_ATTACHED_DRV; 294 else if (mode == XDP_FLAGS_SKB_MODE) 295 return opts.attach_mode == XDP_ATTACHED_SKB; 296 297 return false; 298} 299 300/* Lifted from netlink.c in tools/lib/bpf */ 301static int netlink_recvmsg(int sock, struct msghdr *mhdr, int flags) 302{ 303 int len; 304 305 do { 306 len = recvmsg(sock, mhdr, flags); 307 } while (len < 0 && (errno == EINTR || errno == EAGAIN)); 308 309 if (len < 0) 310 return -errno; 311 return len; 312} 313 314/* Lifted from netlink.c in tools/lib/bpf */ 315static int alloc_iov(struct iovec *iov, int len) 316{ 317 void *nbuf; 318 319 nbuf = realloc(iov->iov_base, len); 320 if (!nbuf) 321 return -ENOMEM; 322 323 iov->iov_base = nbuf; 324 iov->iov_len = len; 325 return 0; 326} 327 328/* Original version lifted from netlink.c in tools/lib/bpf */ 329static int netlink_recv(int sock) 330{ 331 struct iovec iov = {}; 332 struct msghdr mhdr = { 333 .msg_iov = &iov, 334 .msg_iovlen = 1, 335 }; 336 bool multipart = true; 337 struct nlmsgerr *err; 338 struct nlmsghdr *nh; 339 int len, ret; 340 341 ret = alloc_iov(&iov, 4096); 342 if (ret) 343 goto done; 344 345 while (multipart) { 346 multipart = false; 347 len = netlink_recvmsg(sock, &mhdr, MSG_PEEK | MSG_TRUNC); 348 if (len < 0) { 349 ret = len; 350 goto done; 351 } 352 353 if (len > iov.iov_len) { 354 ret = alloc_iov(&iov, len); 355 if (ret) 356 goto done; 357 } 358 359 len = netlink_recvmsg(sock, &mhdr, 0); 360 if (len < 0) { 361 ret = len; 362 goto done; 363 } 364 365 if (len == 0) 366 break; 367 368 for (nh = (struct nlmsghdr *)iov.iov_base; NLMSG_OK(nh, len); 369 nh = NLMSG_NEXT(nh, len)) { 370 if (nh->nlmsg_flags & NLM_F_MULTI) 371 multipart = true; 372 switch (nh->nlmsg_type) { 373 case NLMSG_ERROR: 374 err = (struct nlmsgerr *)NLMSG_DATA(nh); 375 if (!err->error) 376 continue; 377 ret = err->error; 378 goto done; 379 case NLMSG_DONE: 380 ret = 0; 381 goto done; 382 default: 383 break; 384 } 385 } 386 } 387 ret = 0; 388done: 389 free(iov.iov_base); 390 return ret; 391} 392 393int xsk_set_mtu(int ifindex, int mtu) 394{ 395 struct nl_mtu_req req; 396 struct rtattr *rta; 397 int fd, ret; 398 399 fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE); 400 if (fd < 0) 401 return fd; 402 403 memset(&req, 0, sizeof(req)); 404 req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)); 405 req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; 406 req.nh.nlmsg_type = RTM_NEWLINK; 407 req.msg.ifi_family = AF_UNSPEC; 408 req.msg.ifi_index = ifindex; 409 rta = (struct rtattr *)(((char *)&req) + NLMSG_ALIGN(req.nh.nlmsg_len)); 410 rta->rta_type = IFLA_MTU; 411 rta->rta_len = RTA_LENGTH(sizeof(unsigned int)); 412 req.nh.nlmsg_len = NLMSG_ALIGN(req.nh.nlmsg_len) + RTA_LENGTH(sizeof(mtu)); 413 memcpy(RTA_DATA(rta), &mtu, sizeof(mtu)); 414 415 ret = send(fd, &req, req.nh.nlmsg_len, 0); 416 if (ret < 0) { 417 close(fd); 418 return errno; 419 } 420 421 ret = netlink_recv(fd); 422 close(fd); 423 return ret; 424} 425 426int xsk_attach_xdp_program(struct bpf_program *prog, int ifindex, u32 xdp_flags) 427{ 428 int prog_fd; 429 430 prog_fd = bpf_program__fd(prog); 431 return bpf_xdp_attach(ifindex, prog_fd, xdp_flags, NULL); 432} 433 434void xsk_detach_xdp_program(int ifindex, u32 xdp_flags) 435{ 436 bpf_xdp_detach(ifindex, xdp_flags, NULL); 437} 438 439void xsk_clear_xskmap(struct bpf_map *map) 440{ 441 u32 index = 0; 442 int map_fd; 443 444 map_fd = bpf_map__fd(map); 445 bpf_map_delete_elem(map_fd, &index); 446} 447 448int xsk_update_xskmap(struct bpf_map *map, struct xsk_socket *xsk, u32 index) 449{ 450 int map_fd, sock_fd; 451 452 map_fd = bpf_map__fd(map); 453 sock_fd = xsk_socket__fd(xsk); 454 455 return bpf_map_update_elem(map_fd, &index, &sock_fd, 0); 456} 457 458static struct xsk_ctx *xsk_get_ctx(struct xsk_umem *umem, int ifindex, 459 __u32 queue_id) 460{ 461 struct xsk_ctx *ctx; 462 463 if (list_empty(&umem->ctx_list)) 464 return NULL; 465 466 list_for_each_entry(ctx, &umem->ctx_list, list) { 467 if (ctx->ifindex == ifindex && ctx->queue_id == queue_id) { 468 ctx->refcount++; 469 return ctx; 470 } 471 } 472 473 return NULL; 474} 475 476static void xsk_put_ctx(struct xsk_ctx *ctx, bool unmap) 477{ 478 struct xsk_umem *umem = ctx->umem; 479 struct xdp_mmap_offsets off; 480 int err; 481 482 if (--ctx->refcount) 483 return; 484 485 if (!unmap) 486 goto out_free; 487 488 err = xsk_get_mmap_offsets(umem->fd, &off); 489 if (err) 490 goto out_free; 491 492 munmap(ctx->fill->ring - off.fr.desc, off.fr.desc + umem->config.fill_size * 493 sizeof(__u64)); 494 munmap(ctx->comp->ring - off.cr.desc, off.cr.desc + umem->config.comp_size * 495 sizeof(__u64)); 496 497out_free: 498 list_del(&ctx->list); 499 free(ctx); 500} 501 502static struct xsk_ctx *xsk_create_ctx(struct xsk_socket *xsk, 503 struct xsk_umem *umem, int ifindex, 504 __u32 queue_id, 505 struct xsk_ring_prod *fill, 506 struct xsk_ring_cons *comp) 507{ 508 struct xsk_ctx *ctx; 509 int err; 510 511 ctx = calloc(1, sizeof(*ctx)); 512 if (!ctx) 513 return NULL; 514 515 if (!umem->fill_save) { 516 err = xsk_create_umem_rings(umem, xsk->fd, fill, comp); 517 if (err) { 518 free(ctx); 519 return NULL; 520 } 521 } else if (umem->fill_save != fill || umem->comp_save != comp) { 522 /* Copy over rings to new structs. */ 523 memcpy(fill, umem->fill_save, sizeof(*fill)); 524 memcpy(comp, umem->comp_save, sizeof(*comp)); 525 } 526 527 ctx->ifindex = ifindex; 528 ctx->refcount = 1; 529 ctx->umem = umem; 530 ctx->queue_id = queue_id; 531 532 ctx->fill = fill; 533 ctx->comp = comp; 534 list_add(&ctx->list, &umem->ctx_list); 535 return ctx; 536} 537 538int xsk_socket__create_shared(struct xsk_socket **xsk_ptr, 539 int ifindex, 540 __u32 queue_id, struct xsk_umem *umem, 541 struct xsk_ring_cons *rx, 542 struct xsk_ring_prod *tx, 543 struct xsk_ring_prod *fill, 544 struct xsk_ring_cons *comp, 545 const struct xsk_socket_config *usr_config) 546{ 547 bool unmap, rx_setup_done = false, tx_setup_done = false; 548 void *rx_map = NULL, *tx_map = NULL; 549 struct sockaddr_xdp sxdp = {}; 550 struct xdp_mmap_offsets off; 551 struct xsk_socket *xsk; 552 struct xsk_ctx *ctx; 553 int err; 554 555 if (!umem || !xsk_ptr || !(rx || tx)) 556 return -EFAULT; 557 558 unmap = umem->fill_save != fill; 559 560 xsk = calloc(1, sizeof(*xsk)); 561 if (!xsk) 562 return -ENOMEM; 563 564 err = xsk_set_xdp_socket_config(&xsk->config, usr_config); 565 if (err) 566 goto out_xsk_alloc; 567 568 if (umem->refcount++ > 0) { 569 xsk->fd = socket(AF_XDP, SOCK_RAW | SOCK_CLOEXEC, 0); 570 if (xsk->fd < 0) { 571 err = -errno; 572 goto out_xsk_alloc; 573 } 574 } else { 575 xsk->fd = umem->fd; 576 rx_setup_done = umem->rx_ring_setup_done; 577 tx_setup_done = umem->tx_ring_setup_done; 578 } 579 580 ctx = xsk_get_ctx(umem, ifindex, queue_id); 581 if (!ctx) { 582 if (!fill || !comp) { 583 err = -EFAULT; 584 goto out_socket; 585 } 586 587 ctx = xsk_create_ctx(xsk, umem, ifindex, queue_id, fill, comp); 588 if (!ctx) { 589 err = -ENOMEM; 590 goto out_socket; 591 } 592 } 593 xsk->ctx = ctx; 594 595 if (rx && !rx_setup_done) { 596 err = setsockopt(xsk->fd, SOL_XDP, XDP_RX_RING, 597 &xsk->config.rx_size, 598 sizeof(xsk->config.rx_size)); 599 if (err) { 600 err = -errno; 601 goto out_put_ctx; 602 } 603 if (xsk->fd == umem->fd) 604 umem->rx_ring_setup_done = true; 605 } 606 if (tx && !tx_setup_done) { 607 err = setsockopt(xsk->fd, SOL_XDP, XDP_TX_RING, 608 &xsk->config.tx_size, 609 sizeof(xsk->config.tx_size)); 610 if (err) { 611 err = -errno; 612 goto out_put_ctx; 613 } 614 if (xsk->fd == umem->fd) 615 umem->tx_ring_setup_done = true; 616 } 617 618 err = xsk_get_mmap_offsets(xsk->fd, &off); 619 if (err) { 620 err = -errno; 621 goto out_put_ctx; 622 } 623 624 if (rx) { 625 rx_map = mmap(NULL, off.rx.desc + 626 xsk->config.rx_size * sizeof(struct xdp_desc), 627 PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, 628 xsk->fd, XDP_PGOFF_RX_RING); 629 if (rx_map == MAP_FAILED) { 630 err = -errno; 631 goto out_put_ctx; 632 } 633 634 rx->mask = xsk->config.rx_size - 1; 635 rx->size = xsk->config.rx_size; 636 rx->producer = rx_map + off.rx.producer; 637 rx->consumer = rx_map + off.rx.consumer; 638 rx->flags = rx_map + off.rx.flags; 639 rx->ring = rx_map + off.rx.desc; 640 rx->cached_prod = *rx->producer; 641 rx->cached_cons = *rx->consumer; 642 } 643 xsk->rx = rx; 644 645 if (tx) { 646 tx_map = mmap(NULL, off.tx.desc + 647 xsk->config.tx_size * sizeof(struct xdp_desc), 648 PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, 649 xsk->fd, XDP_PGOFF_TX_RING); 650 if (tx_map == MAP_FAILED) { 651 err = -errno; 652 goto out_mmap_rx; 653 } 654 655 tx->mask = xsk->config.tx_size - 1; 656 tx->size = xsk->config.tx_size; 657 tx->producer = tx_map + off.tx.producer; 658 tx->consumer = tx_map + off.tx.consumer; 659 tx->flags = tx_map + off.tx.flags; 660 tx->ring = tx_map + off.tx.desc; 661 tx->cached_prod = *tx->producer; 662 /* cached_cons is r->size bigger than the real consumer pointer 663 * See xsk_prod_nb_free 664 */ 665 tx->cached_cons = *tx->consumer + xsk->config.tx_size; 666 } 667 xsk->tx = tx; 668 669 sxdp.sxdp_family = PF_XDP; 670 sxdp.sxdp_ifindex = ctx->ifindex; 671 sxdp.sxdp_queue_id = ctx->queue_id; 672 if (umem->refcount > 1) { 673 sxdp.sxdp_flags |= XDP_SHARED_UMEM; 674 sxdp.sxdp_shared_umem_fd = umem->fd; 675 } else { 676 sxdp.sxdp_flags = xsk->config.bind_flags; 677 } 678 679 err = bind(xsk->fd, (struct sockaddr *)&sxdp, sizeof(sxdp)); 680 if (err) { 681 err = -errno; 682 goto out_mmap_tx; 683 } 684 685 *xsk_ptr = xsk; 686 umem->fill_save = NULL; 687 umem->comp_save = NULL; 688 return 0; 689 690out_mmap_tx: 691 if (tx) 692 munmap(tx_map, off.tx.desc + 693 xsk->config.tx_size * sizeof(struct xdp_desc)); 694out_mmap_rx: 695 if (rx) 696 munmap(rx_map, off.rx.desc + 697 xsk->config.rx_size * sizeof(struct xdp_desc)); 698out_put_ctx: 699 xsk_put_ctx(ctx, unmap); 700out_socket: 701 if (--umem->refcount) 702 close(xsk->fd); 703out_xsk_alloc: 704 free(xsk); 705 return err; 706} 707 708int xsk_socket__create(struct xsk_socket **xsk_ptr, int ifindex, 709 __u32 queue_id, struct xsk_umem *umem, 710 struct xsk_ring_cons *rx, struct xsk_ring_prod *tx, 711 const struct xsk_socket_config *usr_config) 712{ 713 if (!umem) 714 return -EFAULT; 715 716 return xsk_socket__create_shared(xsk_ptr, ifindex, queue_id, umem, 717 rx, tx, umem->fill_save, 718 umem->comp_save, usr_config); 719} 720 721int xsk_umem__delete(struct xsk_umem *umem) 722{ 723 struct xdp_mmap_offsets off; 724 int err; 725 726 if (!umem) 727 return 0; 728 729 if (umem->refcount) 730 return -EBUSY; 731 732 err = xsk_get_mmap_offsets(umem->fd, &off); 733 if (!err && umem->fill_save && umem->comp_save) { 734 munmap(umem->fill_save->ring - off.fr.desc, 735 off.fr.desc + umem->config.fill_size * sizeof(__u64)); 736 munmap(umem->comp_save->ring - off.cr.desc, 737 off.cr.desc + umem->config.comp_size * sizeof(__u64)); 738 } 739 740 close(umem->fd); 741 free(umem); 742 743 return 0; 744} 745 746void xsk_socket__delete(struct xsk_socket *xsk) 747{ 748 size_t desc_sz = sizeof(struct xdp_desc); 749 struct xdp_mmap_offsets off; 750 struct xsk_umem *umem; 751 struct xsk_ctx *ctx; 752 int err; 753 754 if (!xsk) 755 return; 756 757 ctx = xsk->ctx; 758 umem = ctx->umem; 759 760 xsk_put_ctx(ctx, true); 761 762 err = xsk_get_mmap_offsets(xsk->fd, &off); 763 if (!err) { 764 if (xsk->rx) { 765 munmap(xsk->rx->ring - off.rx.desc, 766 off.rx.desc + xsk->config.rx_size * desc_sz); 767 } 768 if (xsk->tx) { 769 munmap(xsk->tx->ring - off.tx.desc, 770 off.tx.desc + xsk->config.tx_size * desc_sz); 771 } 772 } 773 774 umem->refcount--; 775 /* Do not close an fd that also has an associated umem connected 776 * to it. 777 */ 778 if (xsk->fd != umem->fd) 779 close(xsk->fd); 780 free(xsk); 781} 782