net/xdp/xsk_buff_pool.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include <net/xsk_buff_pool.h>
   4 #include <net/xdp_sock.h>
   5 #include <net/xdp_sock_drv.h>
   6
   7 #include "xsk_queue.h"
   8 #include "xdp_umem.h"
   9 #include "xsk.h"
  10
  11 void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs)
  12 {
  13         unsigned long flags;
  14
  15         if (!xs->tx)
  16                 return;
  17
  18         spin_lock_irqsave(&pool->xsk_tx_list_lock, flags);
  19         list_add_rcu(&xs->tx_list, &pool->xsk_tx_list);
  20         spin_unlock_irqrestore(&pool->xsk_tx_list_lock, flags);
  21 }
  22
  23 void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs)
  24 {
  25         unsigned long flags;
  26
  27         if (!xs->tx)
  28                 return;
  29
  30         spin_lock_irqsave(&pool->xsk_tx_list_lock, flags);
  31         list_del_rcu(&xs->tx_list);
  32         spin_unlock_irqrestore(&pool->xsk_tx_list_lock, flags);
  33 }
  34
  35 void xp_destroy(struct xsk_buff_pool *pool)
  36 {
  37         if (!pool)
  38                 return;
  39
  40         kvfree(pool->tx_descs);
  41         kvfree(pool->heads);
  42         kvfree(pool);
  43 }
  44
  45 int xp_alloc_tx_descs(struct xsk_buff_pool *pool, struct xdp_sock *xs)
  46 {
  47         pool->tx_descs = kvcalloc(xs->tx->nentries, sizeof(*pool->tx_descs),
  48                                   GFP_KERNEL);
  49         if (!pool->tx_descs)
  50                 return -ENOMEM;
  51
  52         return 0;
  53 }
  54
  55 struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
  56                                                 struct xdp_umem *umem)
  57 {
  58         bool unaligned = umem->flags & XDP_UMEM_UNALIGNED_CHUNK_FLAG;
  59         struct xsk_buff_pool *pool;
  60         struct xdp_buff_xsk *xskb;
  61         u32 i, entries;
  62
  63         entries = unaligned ? umem->chunks : 0;
  64         pool = kvzalloc(struct_size(pool, free_heads, entries), GFP_KERNEL);
  65         if (!pool)
  66                 goto out;
  67
  68         pool->heads = kvcalloc(umem->chunks, sizeof(*pool->heads), GFP_KERNEL);
  69         if (!pool->heads)
  70                 goto out;
  71
  72         if (xs->tx)
  73                 if (xp_alloc_tx_descs(pool, xs))
  74                         goto out;
  75
  76         pool->chunk_mask = ~((u64)umem->chunk_size - 1);
  77         pool->addrs_cnt = umem->size;
  78         pool->heads_cnt = umem->chunks;
  79         pool->free_heads_cnt = umem->chunks;
  80         pool->headroom = umem->headroom;
  81         pool->chunk_size = umem->chunk_size;
  82         pool->chunk_shift = ffs(umem->chunk_size) - 1;
  83         pool->unaligned = unaligned;
  84         pool->frame_len = umem->chunk_size - umem->headroom -
  85                 XDP_PACKET_HEADROOM;
  86         pool->umem = umem;
  87         pool->addrs = umem->addrs;
  88         INIT_LIST_HEAD(&pool->free_list);
  89         INIT_LIST_HEAD(&pool->xsk_tx_list);
  90         spin_lock_init(&pool->xsk_tx_list_lock);
  91         spin_lock_init(&pool->cq_lock);
  92         refcount_set(&pool->users, 1);
  93
  94         pool->fq = xs->fq_tmp;
  95         pool->cq = xs->cq_tmp;
  96
  97         for (i = 0; i < pool->free_heads_cnt; i++) {
  98                 xskb = &pool->heads[i];
  99                 xskb->pool = pool;
 100                 xskb->xdp.frame_sz = umem->chunk_size - umem->headroom;
 101                 INIT_LIST_HEAD(&xskb->free_list_node);
 102                 if (pool->unaligned)
 103                         pool->free_heads[i] = xskb;
 104                 else
 105                         xp_init_xskb_addr(xskb, pool, i * pool->chunk_size);
 106         }
 107
 108         return pool;
 109
 110 out:
 111         xp_destroy(pool);
 112         return NULL;
 113 }
 114
 115 void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq)
 116 {
 117         u32 i;
 118
 119         for (i = 0; i < pool->heads_cnt; i++)
 120                 pool->heads[i].xdp.rxq = rxq;
 121 }
 122 EXPORT_SYMBOL(xp_set_rxq_info);
 123
 124 static void xp_disable_drv_zc(struct xsk_buff_pool *pool)
 125 {
 126         struct netdev_bpf bpf;
 127         int err;
 128
 129         ASSERT_RTNL();
 130
 131         if (pool->umem->zc) {
 132                 bpf.command = XDP_SETUP_XSK_POOL;
 133                 bpf.xsk.pool = NULL;
 134                 bpf.xsk.queue_id = pool->queue_id;
 135
 136                 err = pool->netdev->netdev_ops->ndo_bpf(pool->netdev, &bpf);
 137
 138                 if (err)
 139                         WARN(1, "Failed to disable zero-copy!\n");
 140         }
 141 }
 142
 143 int xp_assign_dev(struct xsk_buff_pool *pool,
 144                   struct net_device *netdev, u16 queue_id, u16 flags)
 145 {
 146         bool force_zc, force_copy;
 147         struct netdev_bpf bpf;
 148         int err = 0;
 149
 150         ASSERT_RTNL();
 151
 152         force_zc = flags & XDP_ZEROCOPY;
 153         force_copy = flags & XDP_COPY;
 154
 155         if (force_zc && force_copy)
 156                 return -EINVAL;
 157
 158         if (xsk_get_pool_from_qid(netdev, queue_id))
 159                 return -EBUSY;
 160
 161         pool->netdev = netdev;
 162         pool->queue_id = queue_id;
 163         err = xsk_reg_pool_at_qid(netdev, pool, queue_id);
 164         if (err)
 165                 return err;
 166
 167         if (flags & XDP_USE_NEED_WAKEUP)
 168                 pool->uses_need_wakeup = true;
 169         /* Tx needs to be explicitly woken up the first time.  Also
 170          * for supporting drivers that do not implement this
 171          * feature. They will always have to call sendto() or poll().
 172          */
 173         pool->cached_need_wakeup = XDP_WAKEUP_TX;
 174
 175         dev_hold(netdev);
 176
 177         if (force_copy)
 178                 /* For copy-mode, we are done. */
 179                 return 0;
 180
 181         if (!netdev->netdev_ops->ndo_bpf ||
 182             !netdev->netdev_ops->ndo_xsk_wakeup) {
 183                 err = -EOPNOTSUPP;
 184                 goto err_unreg_pool;
 185         }
 186
 187         bpf.command = XDP_SETUP_XSK_POOL;
 188         bpf.xsk.pool = pool;
 189         bpf.xsk.queue_id = queue_id;
 190
 191         err = netdev->netdev_ops->ndo_bpf(netdev, &bpf);
 192         if (err)
 193                 goto err_unreg_pool;
 194
 195         if (!pool->dma_pages) {
 196                 WARN(1, "Driver did not DMA map zero-copy buffers");
 197                 err = -EINVAL;
 198                 goto err_unreg_xsk;
 199         }
 200         pool->umem->zc = true;
 201         return 0;
 202
 203 err_unreg_xsk:
 204         xp_disable_drv_zc(pool);
 205 err_unreg_pool:
 206         if (!force_zc)
 207                 err = 0; /* fallback to copy mode */
 208         if (err) {
 209                 xsk_clear_pool_at_qid(netdev, queue_id);
 210                 dev_put(netdev);
 211         }
 212         return err;
 213 }
 214
 215 int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_umem *umem,
 216                          struct net_device *dev, u16 queue_id)
 217 {
 218         u16 flags;
 219
 220         /* One fill and completion ring required for each queue id. */
 221         if (!pool->fq || !pool->cq)
 222                 return -EINVAL;
 223
 224         flags = umem->zc ? XDP_ZEROCOPY : XDP_COPY;
 225         if (pool->uses_need_wakeup)
 226                 flags |= XDP_USE_NEED_WAKEUP;
 227
 228         return xp_assign_dev(pool, dev, queue_id, flags);
 229 }
 230
 231 void xp_clear_dev(struct xsk_buff_pool *pool)
 232 {
 233         if (!pool->netdev)
 234                 return;
 235
 236         xp_disable_drv_zc(pool);
 237         xsk_clear_pool_at_qid(pool->netdev, pool->queue_id);
 238         dev_put(pool->netdev);
 239         pool->netdev = NULL;
 240 }
 241
 242 static void xp_release_deferred(struct work_struct *work)
 243 {
 244         struct xsk_buff_pool *pool = container_of(work, struct xsk_buff_pool,
 245                                                   work);
 246
 247         rtnl_lock();
 248         xp_clear_dev(pool);
 249         rtnl_unlock();
 250
 251         if (pool->fq) {
 252                 xskq_destroy(pool->fq);
 253                 pool->fq = NULL;
 254         }
 255
 256         if (pool->cq) {
 257                 xskq_destroy(pool->cq);
 258                 pool->cq = NULL;
 259         }
 260
 261         xdp_put_umem(pool->umem, false);
 262         xp_destroy(pool);
 263 }
 264
 265 void xp_get_pool(struct xsk_buff_pool *pool)
 266 {
 267         refcount_inc(&pool->users);
 268 }
 269
 270 bool xp_put_pool(struct xsk_buff_pool *pool)
 271 {
 272         if (!pool)
 273                 return false;
 274
 275         if (refcount_dec_and_test(&pool->users)) {
 276                 INIT_WORK(&pool->work, xp_release_deferred);
 277                 schedule_work(&pool->work);
 278                 return true;
 279         }
 280
 281         return false;
 282 }
 283
 284 static struct xsk_dma_map *xp_find_dma_map(struct xsk_buff_pool *pool)
 285 {
 286         struct xsk_dma_map *dma_map;
 287
 288         list_for_each_entry(dma_map, &pool->umem->xsk_dma_list, list) {
 289                 if (dma_map->netdev == pool->netdev)
 290                         return dma_map;
 291         }
 292
 293         return NULL;
 294 }
 295
 296 static struct xsk_dma_map *xp_create_dma_map(struct device *dev, struct net_device *netdev,
 297                                              u32 nr_pages, struct xdp_umem *umem)
 298 {
 299         struct xsk_dma_map *dma_map;
 300
 301         dma_map = kzalloc(sizeof(*dma_map), GFP_KERNEL);
 302         if (!dma_map)
 303                 return NULL;
 304
 305         dma_map->dma_pages = kvcalloc(nr_pages, sizeof(*dma_map->dma_pages), GFP_KERNEL);
 306         if (!dma_map->dma_pages) {
 307                 kfree(dma_map);
 308                 return NULL;
 309         }
 310
 311         dma_map->netdev = netdev;
 312         dma_map->dev = dev;
 313         dma_map->dma_need_sync = false;
 314         dma_map->dma_pages_cnt = nr_pages;
 315         refcount_set(&dma_map->users, 1);
 316         list_add(&dma_map->list, &umem->xsk_dma_list);
 317         return dma_map;
 318 }
 319
 320 static void xp_destroy_dma_map(struct xsk_dma_map *dma_map)
 321 {
 322         list_del(&dma_map->list);
 323         kvfree(dma_map->dma_pages);
 324         kfree(dma_map);
 325 }
 326
 327 static void __xp_dma_unmap(struct xsk_dma_map *dma_map, unsigned long attrs)
 328 {
 329         dma_addr_t *dma;
 330         u32 i;
 331
 332         for (i = 0; i < dma_map->dma_pages_cnt; i++) {
 333                 dma = &dma_map->dma_pages[i];
 334                 if (*dma) {
 335                         dma_unmap_page_attrs(dma_map->dev, *dma, PAGE_SIZE,
 336                                              DMA_BIDIRECTIONAL, attrs);
 337                         *dma = 0;
 338                 }
 339         }
 340
 341         xp_destroy_dma_map(dma_map);
 342 }
 343
 344 void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs)
 345 {
 346         struct xsk_dma_map *dma_map;
 347
 348         if (pool->dma_pages_cnt == 0)
 349                 return;
 350
 351         dma_map = xp_find_dma_map(pool);
 352         if (!dma_map) {
 353                 WARN(1, "Could not find dma_map for device");
 354                 return;
 355         }
 356
 357         if (!refcount_dec_and_test(&dma_map->users))
 358                 return;
 359
 360         __xp_dma_unmap(dma_map, attrs);
 361         kvfree(pool->dma_pages);
 362         pool->dma_pages_cnt = 0;
 363         pool->dev = NULL;
 364 }
 365 EXPORT_SYMBOL(xp_dma_unmap);
 366
 367 static void xp_check_dma_contiguity(struct xsk_dma_map *dma_map)
 368 {
 369         u32 i;
 370
 371         for (i = 0; i < dma_map->dma_pages_cnt - 1; i++) {
 372                 if (dma_map->dma_pages[i] + PAGE_SIZE == dma_map->dma_pages[i + 1])
 373                         dma_map->dma_pages[i] |= XSK_NEXT_PG_CONTIG_MASK;
 374                 else
 375                         dma_map->dma_pages[i] &= ~XSK_NEXT_PG_CONTIG_MASK;
 376         }
 377 }
 378
 379 static int xp_init_dma_info(struct xsk_buff_pool *pool, struct xsk_dma_map *dma_map)
 380 {
 381         pool->dma_pages = kvcalloc(dma_map->dma_pages_cnt, sizeof(*pool->dma_pages), GFP_KERNEL);
 382         if (!pool->dma_pages)
 383                 return -ENOMEM;
 384
 385         pool->dev = dma_map->dev;
 386         pool->dma_pages_cnt = dma_map->dma_pages_cnt;
 387         pool->dma_need_sync = dma_map->dma_need_sync;
 388         memcpy(pool->dma_pages, dma_map->dma_pages,
 389                pool->dma_pages_cnt * sizeof(*pool->dma_pages));
 390
 391         return 0;
 392 }
 393
 394 int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev,
 395                unsigned long attrs, struct page **pages, u32 nr_pages)
 396 {
 397         struct xsk_dma_map *dma_map;
 398         dma_addr_t dma;
 399         int err;
 400         u32 i;
 401
 402         dma_map = xp_find_dma_map(pool);
 403         if (dma_map) {
 404                 err = xp_init_dma_info(pool, dma_map);
 405                 if (err)
 406                         return err;
 407
 408                 refcount_inc(&dma_map->users);
 409                 return 0;
 410         }
 411
 412         dma_map = xp_create_dma_map(dev, pool->netdev, nr_pages, pool->umem);
 413         if (!dma_map)
 414                 return -ENOMEM;
 415
 416         for (i = 0; i < dma_map->dma_pages_cnt; i++) {
 417                 dma = dma_map_page_attrs(dev, pages[i], 0, PAGE_SIZE,
 418                                          DMA_BIDIRECTIONAL, attrs);
 419                 if (dma_mapping_error(dev, dma)) {
 420                         __xp_dma_unmap(dma_map, attrs);
 421                         return -ENOMEM;
 422                 }
 423                 if (dma_need_sync(dev, dma))
 424                         dma_map->dma_need_sync = true;
 425                 dma_map->dma_pages[i] = dma;
 426         }
 427
 428         if (pool->unaligned)
 429                 xp_check_dma_contiguity(dma_map);
 430         else
 431                 for (i = 0; i < pool->heads_cnt; i++) {
 432                         struct xdp_buff_xsk *xskb = &pool->heads[i];
 433
 434                         xp_init_xskb_dma(xskb, pool, dma_map->dma_pages, xskb->orig_addr);
 435                 }
 436
 437         err = xp_init_dma_info(pool, dma_map);
 438         if (err) {
 439                 __xp_dma_unmap(dma_map, attrs);
 440                 return err;
 441         }
 442
 443         return 0;
 444 }
 445 EXPORT_SYMBOL(xp_dma_map);
 446
 447 static bool xp_addr_crosses_non_contig_pg(struct xsk_buff_pool *pool,
 448                                           u64 addr)
 449 {
 450         return xp_desc_crosses_non_contig_pg(pool, addr, pool->chunk_size);
 451 }
 452
 453 static bool xp_check_unaligned(struct xsk_buff_pool *pool, u64 *addr)
 454 {
 455         *addr = xp_unaligned_extract_addr(*addr);
 456         if (*addr >= pool->addrs_cnt ||
 457             *addr + pool->chunk_size > pool->addrs_cnt ||
 458             xp_addr_crosses_non_contig_pg(pool, *addr))
 459                 return false;
 460         return true;
 461 }
 462
 463 static bool xp_check_aligned(struct xsk_buff_pool *pool, u64 *addr)
 464 {
 465         *addr = xp_aligned_extract_addr(pool, *addr);
 466         return *addr < pool->addrs_cnt;
 467 }
 468
 469 static struct xdp_buff_xsk *__xp_alloc(struct xsk_buff_pool *pool)
 470 {
 471         struct xdp_buff_xsk *xskb;
 472         u64 addr;
 473         bool ok;
 474
 475         if (pool->free_heads_cnt == 0)
 476                 return NULL;
 477
 478         for (;;) {
 479                 if (!xskq_cons_peek_addr_unchecked(pool->fq, &addr)) {
 480                         pool->fq->queue_empty_descs++;
 481                         return NULL;
 482                 }
 483
 484                 ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
 485                      xp_check_aligned(pool, &addr);
 486                 if (!ok) {
 487                         pool->fq->invalid_descs++;
 488                         xskq_cons_release(pool->fq);
 489                         continue;
 490                 }
 491                 break;
 492         }
 493
 494         if (pool->unaligned) {
 495                 xskb = pool->free_heads[--pool->free_heads_cnt];
 496                 xp_init_xskb_addr(xskb, pool, addr);
 497                 if (pool->dma_pages_cnt)
 498                         xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr);
 499         } else {
 500                 xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)];
 501         }
 502
 503         xskq_cons_release(pool->fq);
 504         return xskb;
 505 }
 506
 507 struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool)
 508 {
 509         struct xdp_buff_xsk *xskb;
 510
 511         if (!pool->free_list_cnt) {
 512                 xskb = __xp_alloc(pool);
 513                 if (!xskb)
 514                         return NULL;
 515         } else {
 516                 pool->free_list_cnt--;
 517                 xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk,
 518                                         free_list_node);
 519                 list_del_init(&xskb->free_list_node);
 520         }
 521
 522         xskb->xdp.data = xskb->xdp.data_hard_start + XDP_PACKET_HEADROOM;
 523         xskb->xdp.data_meta = xskb->xdp.data;
 524
 525         if (pool->dma_need_sync) {
 526                 dma_sync_single_range_for_device(pool->dev, xskb->dma, 0,
 527                                                  pool->frame_len,
 528                                                  DMA_BIDIRECTIONAL);
 529         }
 530         return &xskb->xdp;
 531 }
 532 EXPORT_SYMBOL(xp_alloc);
 533
 534 static u32 xp_alloc_new_from_fq(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
 535 {
 536         u32 i, cached_cons, nb_entries;
 537
 538         if (max > pool->free_heads_cnt)
 539                 max = pool->free_heads_cnt;
 540         max = xskq_cons_nb_entries(pool->fq, max);
 541
 542         cached_cons = pool->fq->cached_cons;
 543         nb_entries = max;
 544         i = max;
 545         while (i--) {
 546                 struct xdp_buff_xsk *xskb;
 547                 u64 addr;
 548                 bool ok;
 549
 550                 __xskq_cons_read_addr_unchecked(pool->fq, cached_cons++, &addr);
 551
 552                 ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
 553                         xp_check_aligned(pool, &addr);
 554                 if (unlikely(!ok)) {
 555                         pool->fq->invalid_descs++;
 556                         nb_entries--;
 557                         continue;
 558                 }
 559
 560                 if (pool->unaligned) {
 561                         xskb = pool->free_heads[--pool->free_heads_cnt];
 562                         xp_init_xskb_addr(xskb, pool, addr);
 563                         if (pool->dma_pages_cnt)
 564                                 xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr);
 565                 } else {
 566                         xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)];
 567                 }
 568
 569                 *xdp = &xskb->xdp;
 570                 xdp++;
 571         }
 572
 573         xskq_cons_release_n(pool->fq, max);
 574         return nb_entries;
 575 }
 576
 577 static u32 xp_alloc_reused(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 nb_entries)
 578 {
 579         struct xdp_buff_xsk *xskb;
 580         u32 i;
 581
 582         nb_entries = min_t(u32, nb_entries, pool->free_list_cnt);
 583
 584         i = nb_entries;
 585         while (i--) {
 586                 xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk, free_list_node);
 587                 list_del_init(&xskb->free_list_node);
 588
 589                 *xdp = &xskb->xdp;
 590                 xdp++;
 591         }
 592         pool->free_list_cnt -= nb_entries;
 593
 594         return nb_entries;
 595 }
 596
 597 u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
 598 {
 599         u32 nb_entries1 = 0, nb_entries2;
 600
 601         if (unlikely(pool->dma_need_sync)) {
 602                 struct xdp_buff *buff;
 603
 604                 /* Slow path */
 605                 buff = xp_alloc(pool);
 606                 if (buff)
 607                         *xdp = buff;
 608                 return !!buff;
 609         }
 610
 611         if (unlikely(pool->free_list_cnt)) {
 612                 nb_entries1 = xp_alloc_reused(pool, xdp, max);
 613                 if (nb_entries1 == max)
 614                         return nb_entries1;
 615
 616                 max -= nb_entries1;
 617                 xdp += nb_entries1;
 618         }
 619
 620         nb_entries2 = xp_alloc_new_from_fq(pool, xdp, max);
 621         if (!nb_entries2)
 622                 pool->fq->queue_empty_descs++;
 623
 624         return nb_entries1 + nb_entries2;
 625 }
 626 EXPORT_SYMBOL(xp_alloc_batch);
 627
 628 bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count)
 629 {
 630         if (pool->free_list_cnt >= count)
 631                 return true;
 632         return xskq_cons_has_entries(pool->fq, count - pool->free_list_cnt);
 633 }
 634 EXPORT_SYMBOL(xp_can_alloc);
 635
 636 void xp_free(struct xdp_buff_xsk *xskb)
 637 {
 638         if (!list_empty(&xskb->free_list_node))
 639                 return;
 640
 641         xskb->pool->free_list_cnt++;
 642         list_add(&xskb->free_list_node, &xskb->pool->free_list);
 643 }
 644 EXPORT_SYMBOL(xp_free);
 645
 646 void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
 647 {
 648         addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
 649         return pool->addrs + addr;
 650 }
 651 EXPORT_SYMBOL(xp_raw_get_data);
 652
 653 dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr)
 654 {
 655         addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
 656         return (pool->dma_pages[addr >> PAGE_SHIFT] &
 657                 ~XSK_NEXT_PG_CONTIG_MASK) +
 658                 (addr & ~PAGE_MASK);
 659 }
 660 EXPORT_SYMBOL(xp_raw_get_dma);
 661
 662 void xp_dma_sync_for_cpu_slow(struct xdp_buff_xsk *xskb)
 663 {
 664         dma_sync_single_range_for_cpu(xskb->pool->dev, xskb->dma, 0,
 665                                       xskb->pool->frame_len, DMA_BIDIRECTIONAL);
 666 }
 667 EXPORT_SYMBOL(xp_dma_sync_for_cpu_slow);
 668
 669 void xp_dma_sync_for_device_slow(struct xsk_buff_pool *pool, dma_addr_t dma,
 670                                  size_t size)
 671 {
 672         dma_sync_single_range_for_device(pool->dev, dma, 0,
 673                                          size, DMA_BIDIRECTIONAL);
 674 }
 675 EXPORT_SYMBOL(xp_dma_sync_for_device_slow);