net/xdp/xsk.c

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