1 // SPDX-License-Identifier: GPL-2.0 2 /* XDP sockets 3 * 4 * AF_XDP sockets allows a channel between XDP programs and userspace 5 * applications. 6 * Copyright(c) 2018 Intel Corporation. 7 * 8 * Author(s): Björn Töpel <bjorn.topel@intel.com> 9 * Magnus Karlsson <magnus.karlsson@intel.com> 10 */ 11 12 #define pr_fmt(fmt) "AF_XDP: %s: " fmt, __func__ 13 14 #include <linux/if_xdp.h> 15 #include <linux/init.h> 16 #include <linux/sched/mm.h> 17 #include <linux/sched/signal.h> 18 #include <linux/sched/task.h> 19 #include <linux/socket.h> 20 #include <linux/file.h> 21 #include <linux/uaccess.h> 22 #include <linux/net.h> 23 #include <linux/netdevice.h> 24 #include <linux/rculist.h> 25 #include <net/xdp_sock.h> 26 #include <net/xdp.h> 27 28 #include "xsk_queue.h" 29 #include "xdp_umem.h" 30 #include "xsk.h" 31 32 #define TX_BATCH_SIZE 16 33 34 bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs) 35 { 36 return READ_ONCE(xs->rx) && READ_ONCE(xs->umem) && 37 READ_ONCE(xs->umem->fq); 38 } 39 40 u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr) 41 { 42 return xskq_peek_addr(umem->fq, addr); 43 } 44 EXPORT_SYMBOL(xsk_umem_peek_addr); 45 46 void xsk_umem_discard_addr(struct xdp_umem *umem) 47 { 48 xskq_discard_addr(umem->fq); 49 } 50 EXPORT_SYMBOL(xsk_umem_discard_addr); 51 52 static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len) 53 { 54 void *to_buf, *from_buf; 55 u32 metalen; 56 u64 addr; 57 int err; 58 59 if (!xskq_peek_addr(xs->umem->fq, &addr) || 60 len > xs->umem->chunk_size_nohr - XDP_PACKET_HEADROOM) { 61 xs->rx_dropped++; 62 return -ENOSPC; 63 } 64 65 addr += xs->umem->headroom; 66 67 if (unlikely(xdp_data_meta_unsupported(xdp))) { 68 from_buf = xdp->data; 69 metalen = 0; 70 } else { 71 from_buf = xdp->data_meta; 72 metalen = xdp->data - xdp->data_meta; 73 } 74 75 to_buf = xdp_umem_get_data(xs->umem, addr); 76 memcpy(to_buf, from_buf, len + metalen); 77 addr += metalen; 78 err = xskq_produce_batch_desc(xs->rx, addr, len); 79 if (!err) { 80 xskq_discard_addr(xs->umem->fq); 81 xdp_return_buff(xdp); 82 return 0; 83 } 84 85 xs->rx_dropped++; 86 return err; 87 } 88 89 static int __xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len) 90 { 91 int err = xskq_produce_batch_desc(xs->rx, (u64)xdp->handle, len); 92 93 if (err) 94 xs->rx_dropped++; 95 96 return err; 97 } 98 99 int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) 100 { 101 u32 len; 102 103 if (xs->dev != xdp->rxq->dev || xs->queue_id != xdp->rxq->queue_index) 104 return -EINVAL; 105 106 len = xdp->data_end - xdp->data; 107 108 return (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY) ? 109 __xsk_rcv_zc(xs, xdp, len) : __xsk_rcv(xs, xdp, len); 110 } 111 112 void xsk_flush(struct xdp_sock *xs) 113 { 114 xskq_produce_flush_desc(xs->rx); 115 xs->sk.sk_data_ready(&xs->sk); 116 } 117 118 int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) 119 { 120 u32 metalen = xdp->data - xdp->data_meta; 121 u32 len = xdp->data_end - xdp->data; 122 void *buffer; 123 u64 addr; 124 int err; 125 126 if (xs->dev != xdp->rxq->dev || xs->queue_id != xdp->rxq->queue_index) 127 return -EINVAL; 128 129 if (!xskq_peek_addr(xs->umem->fq, &addr) || 130 len > xs->umem->chunk_size_nohr - XDP_PACKET_HEADROOM) { 131 xs->rx_dropped++; 132 return -ENOSPC; 133 } 134 135 addr += xs->umem->headroom; 136 137 buffer = xdp_umem_get_data(xs->umem, addr); 138 memcpy(buffer, xdp->data_meta, len + metalen); 139 addr += metalen; 140 err = xskq_produce_batch_desc(xs->rx, addr, len); 141 if (!err) { 142 xskq_discard_addr(xs->umem->fq); 143 xsk_flush(xs); 144 return 0; 145 } 146 147 xs->rx_dropped++; 148 return err; 149 } 150 151 void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries) 152 { 153 xskq_produce_flush_addr_n(umem->cq, nb_entries); 154 } 155 EXPORT_SYMBOL(xsk_umem_complete_tx); 156 157 void xsk_umem_consume_tx_done(struct xdp_umem *umem) 158 { 159 struct xdp_sock *xs; 160 161 rcu_read_lock(); 162 list_for_each_entry_rcu(xs, &umem->xsk_list, list) { 163 xs->sk.sk_write_space(&xs->sk); 164 } 165 rcu_read_unlock(); 166 } 167 EXPORT_SYMBOL(xsk_umem_consume_tx_done); 168 169 bool xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma, u32 *len) 170 { 171 struct xdp_desc desc; 172 struct xdp_sock *xs; 173 174 rcu_read_lock(); 175 list_for_each_entry_rcu(xs, &umem->xsk_list, list) { 176 if (!xskq_peek_desc(xs->tx, &desc)) 177 continue; 178 179 if (xskq_produce_addr_lazy(umem->cq, desc.addr)) 180 goto out; 181 182 *dma = xdp_umem_get_dma(umem, desc.addr); 183 *len = desc.len; 184 185 xskq_discard_desc(xs->tx); 186 rcu_read_unlock(); 187 return true; 188 } 189 190 out: 191 rcu_read_unlock(); 192 return false; 193 } 194 EXPORT_SYMBOL(xsk_umem_consume_tx); 195 196 static int xsk_zc_xmit(struct sock *sk) 197 { 198 struct xdp_sock *xs = xdp_sk(sk); 199 struct net_device *dev = xs->dev; 200 201 return dev->netdev_ops->ndo_xsk_async_xmit(dev, xs->queue_id); 202 } 203 204 static void xsk_destruct_skb(struct sk_buff *skb) 205 { 206 u64 addr = (u64)(long)skb_shinfo(skb)->destructor_arg; 207 struct xdp_sock *xs = xdp_sk(skb->sk); 208 unsigned long flags; 209 210 spin_lock_irqsave(&xs->tx_completion_lock, flags); 211 WARN_ON_ONCE(xskq_produce_addr(xs->umem->cq, addr)); 212 spin_unlock_irqrestore(&xs->tx_completion_lock, flags); 213 214 sock_wfree(skb); 215 } 216 217 static int xsk_generic_xmit(struct sock *sk, struct msghdr *m, 218 size_t total_len) 219 { 220 u32 max_batch = TX_BATCH_SIZE; 221 struct xdp_sock *xs = xdp_sk(sk); 222 bool sent_frame = false; 223 struct xdp_desc desc; 224 struct sk_buff *skb; 225 int err = 0; 226 227 mutex_lock(&xs->mutex); 228 229 while (xskq_peek_desc(xs->tx, &desc)) { 230 char *buffer; 231 u64 addr; 232 u32 len; 233 234 if (max_batch-- == 0) { 235 err = -EAGAIN; 236 goto out; 237 } 238 239 if (xskq_reserve_addr(xs->umem->cq)) 240 goto out; 241 242 if (xs->queue_id >= xs->dev->real_num_tx_queues) 243 goto out; 244 245 len = desc.len; 246 skb = sock_alloc_send_skb(sk, len, 1, &err); 247 if (unlikely(!skb)) { 248 err = -EAGAIN; 249 goto out; 250 } 251 252 skb_put(skb, len); 253 addr = desc.addr; 254 buffer = xdp_umem_get_data(xs->umem, addr); 255 err = skb_store_bits(skb, 0, buffer, len); 256 if (unlikely(err)) { 257 kfree_skb(skb); 258 goto out; 259 } 260 261 skb->dev = xs->dev; 262 skb->priority = sk->sk_priority; 263 skb->mark = sk->sk_mark; 264 skb_shinfo(skb)->destructor_arg = (void *)(long)addr; 265 skb->destructor = xsk_destruct_skb; 266 267 err = dev_direct_xmit(skb, xs->queue_id); 268 xskq_discard_desc(xs->tx); 269 /* Ignore NET_XMIT_CN as packet might have been sent */ 270 if (err == NET_XMIT_DROP || err == NETDEV_TX_BUSY) { 271 /* SKB completed but not sent */ 272 err = -EBUSY; 273 goto out; 274 } 275 276 sent_frame = true; 277 } 278 279 out: 280 if (sent_frame) 281 sk->sk_write_space(sk); 282 283 mutex_unlock(&xs->mutex); 284 return err; 285 } 286 287 static int xsk_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) 288 { 289 bool need_wait = !(m->msg_flags & MSG_DONTWAIT); 290 struct sock *sk = sock->sk; 291 struct xdp_sock *xs = xdp_sk(sk); 292 293 if (unlikely(!xs->dev)) 294 return -ENXIO; 295 if (unlikely(!(xs->dev->flags & IFF_UP))) 296 return -ENETDOWN; 297 if (unlikely(!xs->tx)) 298 return -ENOBUFS; 299 if (need_wait) 300 return -EOPNOTSUPP; 301 302 return (xs->zc) ? xsk_zc_xmit(sk) : xsk_generic_xmit(sk, m, total_len); 303 } 304 305 static unsigned int xsk_poll(struct file *file, struct socket *sock, 306 struct poll_table_struct *wait) 307 { 308 unsigned int mask = datagram_poll(file, sock, wait); 309 struct sock *sk = sock->sk; 310 struct xdp_sock *xs = xdp_sk(sk); 311 312 if (xs->rx && !xskq_empty_desc(xs->rx)) 313 mask |= POLLIN | POLLRDNORM; 314 if (xs->tx && !xskq_full_desc(xs->tx)) 315 mask |= POLLOUT | POLLWRNORM; 316 317 return mask; 318 } 319 320 static int xsk_init_queue(u32 entries, struct xsk_queue **queue, 321 bool umem_queue) 322 { 323 struct xsk_queue *q; 324 325 if (entries == 0 || *queue || !is_power_of_2(entries)) 326 return -EINVAL; 327 328 q = xskq_create(entries, umem_queue); 329 if (!q) 330 return -ENOMEM; 331 332 /* Make sure queue is ready before it can be seen by others */ 333 smp_wmb(); 334 *queue = q; 335 return 0; 336 } 337 338 static int xsk_release(struct socket *sock) 339 { 340 struct sock *sk = sock->sk; 341 struct xdp_sock *xs = xdp_sk(sk); 342 struct net *net; 343 344 if (!sk) 345 return 0; 346 347 net = sock_net(sk); 348 349 mutex_lock(&net->xdp.lock); 350 sk_del_node_init_rcu(sk); 351 mutex_unlock(&net->xdp.lock); 352 353 local_bh_disable(); 354 sock_prot_inuse_add(net, sk->sk_prot, -1); 355 local_bh_enable(); 356 357 if (xs->dev) { 358 struct net_device *dev = xs->dev; 359 360 /* Wait for driver to stop using the xdp socket. */ 361 xdp_del_sk_umem(xs->umem, xs); 362 xs->dev = NULL; 363 synchronize_net(); 364 dev_put(dev); 365 } 366 367 xskq_destroy(xs->rx); 368 xskq_destroy(xs->tx); 369 xdp_put_umem(xs->umem); 370 371 sock_orphan(sk); 372 sock->sk = NULL; 373 374 sk_refcnt_debug_release(sk); 375 sock_put(sk); 376 377 return 0; 378 } 379 380 static struct socket *xsk_lookup_xsk_from_fd(int fd) 381 { 382 struct socket *sock; 383 int err; 384 385 sock = sockfd_lookup(fd, &err); 386 if (!sock) 387 return ERR_PTR(-ENOTSOCK); 388 389 if (sock->sk->sk_family != PF_XDP) { 390 sockfd_put(sock); 391 return ERR_PTR(-ENOPROTOOPT); 392 } 393 394 return sock; 395 } 396 397 static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) 398 { 399 struct sockaddr_xdp *sxdp = (struct sockaddr_xdp *)addr; 400 struct sock *sk = sock->sk; 401 struct xdp_sock *xs = xdp_sk(sk); 402 struct net_device *dev; 403 u32 flags, qid; 404 int err = 0; 405 406 if (addr_len < sizeof(struct sockaddr_xdp)) 407 return -EINVAL; 408 if (sxdp->sxdp_family != AF_XDP) 409 return -EINVAL; 410 411 mutex_lock(&xs->mutex); 412 if (xs->dev) { 413 err = -EBUSY; 414 goto out_release; 415 } 416 417 dev = dev_get_by_index(sock_net(sk), sxdp->sxdp_ifindex); 418 if (!dev) { 419 err = -ENODEV; 420 goto out_release; 421 } 422 423 if (!xs->rx && !xs->tx) { 424 err = -EINVAL; 425 goto out_unlock; 426 } 427 428 qid = sxdp->sxdp_queue_id; 429 flags = sxdp->sxdp_flags; 430 431 if (flags & XDP_SHARED_UMEM) { 432 struct xdp_sock *umem_xs; 433 struct socket *sock; 434 435 if ((flags & XDP_COPY) || (flags & XDP_ZEROCOPY)) { 436 /* Cannot specify flags for shared sockets. */ 437 err = -EINVAL; 438 goto out_unlock; 439 } 440 441 if (xs->umem) { 442 /* We have already our own. */ 443 err = -EINVAL; 444 goto out_unlock; 445 } 446 447 sock = xsk_lookup_xsk_from_fd(sxdp->sxdp_shared_umem_fd); 448 if (IS_ERR(sock)) { 449 err = PTR_ERR(sock); 450 goto out_unlock; 451 } 452 453 umem_xs = xdp_sk(sock->sk); 454 if (!umem_xs->umem) { 455 /* No umem to inherit. */ 456 err = -EBADF; 457 sockfd_put(sock); 458 goto out_unlock; 459 } else if (umem_xs->dev != dev || umem_xs->queue_id != qid) { 460 err = -EINVAL; 461 sockfd_put(sock); 462 goto out_unlock; 463 } 464 465 xdp_get_umem(umem_xs->umem); 466 xs->umem = umem_xs->umem; 467 sockfd_put(sock); 468 } else if (!xs->umem || !xdp_umem_validate_queues(xs->umem)) { 469 err = -EINVAL; 470 goto out_unlock; 471 } else { 472 /* This xsk has its own umem. */ 473 xskq_set_umem(xs->umem->fq, xs->umem->size, 474 xs->umem->chunk_mask); 475 xskq_set_umem(xs->umem->cq, xs->umem->size, 476 xs->umem->chunk_mask); 477 478 err = xdp_umem_assign_dev(xs->umem, dev, qid, flags); 479 if (err) 480 goto out_unlock; 481 } 482 483 xs->dev = dev; 484 xs->zc = xs->umem->zc; 485 xs->queue_id = qid; 486 xskq_set_umem(xs->rx, xs->umem->size, xs->umem->chunk_mask); 487 xskq_set_umem(xs->tx, xs->umem->size, xs->umem->chunk_mask); 488 xdp_add_sk_umem(xs->umem, xs); 489 490 out_unlock: 491 if (err) 492 dev_put(dev); 493 out_release: 494 mutex_unlock(&xs->mutex); 495 return err; 496 } 497 498 static int xsk_setsockopt(struct socket *sock, int level, int optname, 499 char __user *optval, unsigned int optlen) 500 { 501 struct sock *sk = sock->sk; 502 struct xdp_sock *xs = xdp_sk(sk); 503 int err; 504 505 if (level != SOL_XDP) 506 return -ENOPROTOOPT; 507 508 switch (optname) { 509 case XDP_RX_RING: 510 case XDP_TX_RING: 511 { 512 struct xsk_queue **q; 513 int entries; 514 515 if (optlen < sizeof(entries)) 516 return -EINVAL; 517 if (copy_from_user(&entries, optval, sizeof(entries))) 518 return -EFAULT; 519 520 mutex_lock(&xs->mutex); 521 q = (optname == XDP_TX_RING) ? &xs->tx : &xs->rx; 522 err = xsk_init_queue(entries, q, false); 523 mutex_unlock(&xs->mutex); 524 return err; 525 } 526 case XDP_UMEM_REG: 527 { 528 struct xdp_umem_reg mr; 529 struct xdp_umem *umem; 530 531 if (copy_from_user(&mr, optval, sizeof(mr))) 532 return -EFAULT; 533 534 mutex_lock(&xs->mutex); 535 if (xs->umem) { 536 mutex_unlock(&xs->mutex); 537 return -EBUSY; 538 } 539 540 umem = xdp_umem_create(&mr); 541 if (IS_ERR(umem)) { 542 mutex_unlock(&xs->mutex); 543 return PTR_ERR(umem); 544 } 545 546 /* Make sure umem is ready before it can be seen by others */ 547 smp_wmb(); 548 xs->umem = umem; 549 mutex_unlock(&xs->mutex); 550 return 0; 551 } 552 case XDP_UMEM_FILL_RING: 553 case XDP_UMEM_COMPLETION_RING: 554 { 555 struct xsk_queue **q; 556 int entries; 557 558 if (copy_from_user(&entries, optval, sizeof(entries))) 559 return -EFAULT; 560 561 mutex_lock(&xs->mutex); 562 if (!xs->umem) { 563 mutex_unlock(&xs->mutex); 564 return -EINVAL; 565 } 566 567 q = (optname == XDP_UMEM_FILL_RING) ? &xs->umem->fq : 568 &xs->umem->cq; 569 err = xsk_init_queue(entries, q, true); 570 mutex_unlock(&xs->mutex); 571 return err; 572 } 573 default: 574 break; 575 } 576 577 return -ENOPROTOOPT; 578 } 579 580 static int xsk_getsockopt(struct socket *sock, int level, int optname, 581 char __user *optval, int __user *optlen) 582 { 583 struct sock *sk = sock->sk; 584 struct xdp_sock *xs = xdp_sk(sk); 585 int len; 586 587 if (level != SOL_XDP) 588 return -ENOPROTOOPT; 589 590 if (get_user(len, optlen)) 591 return -EFAULT; 592 if (len < 0) 593 return -EINVAL; 594 595 switch (optname) { 596 case XDP_STATISTICS: 597 { 598 struct xdp_statistics stats; 599 600 if (len < sizeof(stats)) 601 return -EINVAL; 602 603 mutex_lock(&xs->mutex); 604 stats.rx_dropped = xs->rx_dropped; 605 stats.rx_invalid_descs = xskq_nb_invalid_descs(xs->rx); 606 stats.tx_invalid_descs = xskq_nb_invalid_descs(xs->tx); 607 mutex_unlock(&xs->mutex); 608 609 if (copy_to_user(optval, &stats, sizeof(stats))) 610 return -EFAULT; 611 if (put_user(sizeof(stats), optlen)) 612 return -EFAULT; 613 614 return 0; 615 } 616 case XDP_MMAP_OFFSETS: 617 { 618 struct xdp_mmap_offsets off; 619 620 if (len < sizeof(off)) 621 return -EINVAL; 622 623 off.rx.producer = offsetof(struct xdp_rxtx_ring, ptrs.producer); 624 off.rx.consumer = offsetof(struct xdp_rxtx_ring, ptrs.consumer); 625 off.rx.desc = offsetof(struct xdp_rxtx_ring, desc); 626 off.tx.producer = offsetof(struct xdp_rxtx_ring, ptrs.producer); 627 off.tx.consumer = offsetof(struct xdp_rxtx_ring, ptrs.consumer); 628 off.tx.desc = offsetof(struct xdp_rxtx_ring, desc); 629 630 off.fr.producer = offsetof(struct xdp_umem_ring, ptrs.producer); 631 off.fr.consumer = offsetof(struct xdp_umem_ring, ptrs.consumer); 632 off.fr.desc = offsetof(struct xdp_umem_ring, desc); 633 off.cr.producer = offsetof(struct xdp_umem_ring, ptrs.producer); 634 off.cr.consumer = offsetof(struct xdp_umem_ring, ptrs.consumer); 635 off.cr.desc = offsetof(struct xdp_umem_ring, desc); 636 637 len = sizeof(off); 638 if (copy_to_user(optval, &off, len)) 639 return -EFAULT; 640 if (put_user(len, optlen)) 641 return -EFAULT; 642 643 return 0; 644 } 645 default: 646 break; 647 } 648 649 return -EOPNOTSUPP; 650 } 651 652 static int xsk_mmap(struct file *file, struct socket *sock, 653 struct vm_area_struct *vma) 654 { 655 loff_t offset = (loff_t)vma->vm_pgoff << PAGE_SHIFT; 656 unsigned long size = vma->vm_end - vma->vm_start; 657 struct xdp_sock *xs = xdp_sk(sock->sk); 658 struct xsk_queue *q = NULL; 659 struct xdp_umem *umem; 660 unsigned long pfn; 661 struct page *qpg; 662 663 if (offset == XDP_PGOFF_RX_RING) { 664 q = READ_ONCE(xs->rx); 665 } else if (offset == XDP_PGOFF_TX_RING) { 666 q = READ_ONCE(xs->tx); 667 } else { 668 umem = READ_ONCE(xs->umem); 669 if (!umem) 670 return -EINVAL; 671 672 if (offset == XDP_UMEM_PGOFF_FILL_RING) 673 q = READ_ONCE(umem->fq); 674 else if (offset == XDP_UMEM_PGOFF_COMPLETION_RING) 675 q = READ_ONCE(umem->cq); 676 } 677 678 if (!q) 679 return -EINVAL; 680 681 qpg = virt_to_head_page(q->ring); 682 if (size > (PAGE_SIZE << compound_order(qpg))) 683 return -EINVAL; 684 685 pfn = virt_to_phys(q->ring) >> PAGE_SHIFT; 686 return remap_pfn_range(vma, vma->vm_start, pfn, 687 size, vma->vm_page_prot); 688 } 689 690 static struct proto xsk_proto = { 691 .name = "XDP", 692 .owner = THIS_MODULE, 693 .obj_size = sizeof(struct xdp_sock), 694 }; 695 696 static const struct proto_ops xsk_proto_ops = { 697 .family = PF_XDP, 698 .owner = THIS_MODULE, 699 .release = xsk_release, 700 .bind = xsk_bind, 701 .connect = sock_no_connect, 702 .socketpair = sock_no_socketpair, 703 .accept = sock_no_accept, 704 .getname = sock_no_getname, 705 .poll = xsk_poll, 706 .ioctl = sock_no_ioctl, 707 .listen = sock_no_listen, 708 .shutdown = sock_no_shutdown, 709 .setsockopt = xsk_setsockopt, 710 .getsockopt = xsk_getsockopt, 711 .sendmsg = xsk_sendmsg, 712 .recvmsg = sock_no_recvmsg, 713 .mmap = xsk_mmap, 714 .sendpage = sock_no_sendpage, 715 }; 716 717 static int xsk_create(struct net *net, struct socket *sock, int protocol, 718 int kern) 719 { 720 struct sock *sk; 721 struct xdp_sock *xs; 722 723 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 724 return -EPERM; 725 if (sock->type != SOCK_RAW) 726 return -ESOCKTNOSUPPORT; 727 728 if (protocol) 729 return -EPROTONOSUPPORT; 730 731 sock->state = SS_UNCONNECTED; 732 733 sk = sk_alloc(net, PF_XDP, GFP_KERNEL, &xsk_proto, kern); 734 if (!sk) 735 return -ENOBUFS; 736 737 sock->ops = &xsk_proto_ops; 738 739 sock_init_data(sock, sk); 740 741 sk->sk_family = PF_XDP; 742 743 sock_set_flag(sk, SOCK_RCU_FREE); 744 745 xs = xdp_sk(sk); 746 mutex_init(&xs->mutex); 747 spin_lock_init(&xs->tx_completion_lock); 748 749 mutex_lock(&net->xdp.lock); 750 sk_add_node_rcu(sk, &net->xdp.list); 751 mutex_unlock(&net->xdp.lock); 752 753 local_bh_disable(); 754 sock_prot_inuse_add(net, &xsk_proto, 1); 755 local_bh_enable(); 756 757 return 0; 758 } 759 760 static const struct net_proto_family xsk_family_ops = { 761 .family = PF_XDP, 762 .create = xsk_create, 763 .owner = THIS_MODULE, 764 }; 765 766 static int __net_init xsk_net_init(struct net *net) 767 { 768 mutex_init(&net->xdp.lock); 769 INIT_HLIST_HEAD(&net->xdp.list); 770 return 0; 771 } 772 773 static void __net_exit xsk_net_exit(struct net *net) 774 { 775 WARN_ON_ONCE(!hlist_empty(&net->xdp.list)); 776 } 777 778 static struct pernet_operations xsk_net_ops = { 779 .init = xsk_net_init, 780 .exit = xsk_net_exit, 781 }; 782 783 static int __init xsk_init(void) 784 { 785 int err; 786 787 err = proto_register(&xsk_proto, 0 /* no slab */); 788 if (err) 789 goto out; 790 791 err = sock_register(&xsk_family_ops); 792 if (err) 793 goto out_proto; 794 795 err = register_pernet_subsys(&xsk_net_ops); 796 if (err) 797 goto out_sk; 798 return 0; 799 800 out_sk: 801 sock_unregister(PF_XDP); 802 out_proto: 803 proto_unregister(&xsk_proto); 804 out: 805 return err; 806 } 807 808 fs_initcall(xsk_init); 809