1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <linux/netdevice.h> 4 #include <net/netdev_lock.h> 5 #include <net/xsk_buff_pool.h> 6 #include <net/xdp_sock.h> 7 #include <net/xdp_sock_drv.h> 8 9 #include "xsk_queue.h" 10 #include "xdp_umem.h" 11 #include "xsk.h" 12 13 void xp_add_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs) 14 { 15 if (!xs->tx) 16 return; 17 18 spin_lock(&pool->xsk_tx_list_lock); 19 list_add_rcu(&xs->tx_list, &pool->xsk_tx_list); 20 spin_unlock(&pool->xsk_tx_list_lock); 21 } 22 23 void xp_del_xsk(struct xsk_buff_pool *pool, struct xdp_sock *xs) 24 { 25 if (!xs->tx) 26 return; 27 28 spin_lock(&pool->xsk_tx_list_lock); 29 list_del_rcu(&xs->tx_list); 30 spin_unlock(&pool->xsk_tx_list_lock); 31 } 32 33 void xp_destroy(struct xsk_buff_pool *pool) 34 { 35 if (!pool) 36 return; 37 38 kvfree(pool->tx_descs); 39 kvfree(pool->heads); 40 kvfree(pool); 41 } 42 43 int xp_alloc_tx_descs(struct xsk_buff_pool *pool, struct xdp_sock *xs) 44 { 45 pool->tx_descs = kvcalloc(xs->tx->nentries, sizeof(*pool->tx_descs), 46 GFP_KERNEL); 47 if (!pool->tx_descs) 48 return -ENOMEM; 49 50 return 0; 51 } 52 53 struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, 54 struct xdp_umem *umem) 55 { 56 bool unaligned = umem->flags & XDP_UMEM_UNALIGNED_CHUNK_FLAG; 57 struct xsk_buff_pool *pool; 58 struct xdp_buff_xsk *xskb; 59 u32 i, entries; 60 61 entries = unaligned ? umem->chunks : 0; 62 pool = kvzalloc(struct_size(pool, free_heads, entries), GFP_KERNEL); 63 if (!pool) 64 goto out; 65 66 pool->heads = kvcalloc(umem->chunks, sizeof(*pool->heads), GFP_KERNEL); 67 if (!pool->heads) 68 goto out; 69 70 if (xs->tx) 71 if (xp_alloc_tx_descs(pool, xs)) 72 goto out; 73 74 pool->chunk_mask = ~((u64)umem->chunk_size - 1); 75 pool->addrs_cnt = umem->size; 76 pool->heads_cnt = umem->chunks; 77 pool->free_heads_cnt = umem->chunks; 78 pool->headroom = umem->headroom; 79 pool->chunk_size = umem->chunk_size; 80 pool->chunk_shift = ffs(umem->chunk_size) - 1; 81 pool->unaligned = unaligned; 82 pool->frame_len = umem->chunk_size - umem->headroom - 83 XDP_PACKET_HEADROOM; 84 pool->umem = umem; 85 pool->addrs = umem->addrs; 86 pool->tx_metadata_len = umem->tx_metadata_len; 87 pool->tx_sw_csum = umem->flags & XDP_UMEM_TX_SW_CSUM; 88 spin_lock_init(&pool->rx_lock); 89 INIT_LIST_HEAD(&pool->free_list); 90 INIT_LIST_HEAD(&pool->xskb_list); 91 INIT_LIST_HEAD(&pool->xsk_tx_list); 92 spin_lock_init(&pool->xsk_tx_list_lock); 93 spin_lock_init(&pool->cq_prod_lock); 94 spin_lock_init(&pool->cq_cached_prod_lock); 95 refcount_set(&pool->users, 1); 96 97 pool->fq = xs->fq_tmp; 98 pool->cq = xs->cq_tmp; 99 100 for (i = 0; i < pool->free_heads_cnt; i++) { 101 xskb = &pool->heads[i]; 102 xskb->pool = pool; 103 xskb->xdp.frame_sz = umem->chunk_size - umem->headroom; 104 INIT_LIST_HEAD(&xskb->list_node); 105 if (pool->unaligned) 106 pool->free_heads[i] = xskb; 107 else 108 xp_init_xskb_addr(xskb, pool, (u64)i * pool->chunk_size); 109 } 110 111 return pool; 112 113 out: 114 xp_destroy(pool); 115 return NULL; 116 } 117 118 void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq) 119 { 120 u32 i; 121 122 for (i = 0; i < pool->heads_cnt; i++) 123 pool->heads[i].xdp.rxq = rxq; 124 } 125 EXPORT_SYMBOL(xp_set_rxq_info); 126 127 void xp_fill_cb(struct xsk_buff_pool *pool, struct xsk_cb_desc *desc) 128 { 129 u32 i; 130 131 for (i = 0; i < pool->heads_cnt; i++) { 132 struct xdp_buff_xsk *xskb = &pool->heads[i]; 133 134 memcpy(xskb->cb + desc->off, desc->src, desc->bytes); 135 } 136 } 137 EXPORT_SYMBOL(xp_fill_cb); 138 139 static void xp_disable_drv_zc(struct xsk_buff_pool *pool) 140 { 141 struct netdev_bpf bpf; 142 int err; 143 144 ASSERT_RTNL(); 145 146 if (pool->umem->zc) { 147 bpf.command = XDP_SETUP_XSK_POOL; 148 bpf.xsk.pool = NULL; 149 bpf.xsk.queue_id = pool->queue_id; 150 151 err = pool->netdev->netdev_ops->ndo_bpf(pool->netdev, &bpf); 152 153 if (err) 154 WARN(1, "Failed to disable zero-copy!\n"); 155 } 156 } 157 158 #define NETDEV_XDP_ACT_ZC (NETDEV_XDP_ACT_BASIC | \ 159 NETDEV_XDP_ACT_REDIRECT | \ 160 NETDEV_XDP_ACT_XSK_ZEROCOPY) 161 162 int xp_assign_dev(struct xsk_buff_pool *pool, 163 struct net_device *netdev, u16 queue_id, u16 flags) 164 { 165 bool force_zc, force_copy; 166 struct netdev_bpf bpf; 167 int err = 0; 168 169 ASSERT_RTNL(); 170 171 force_zc = flags & XDP_ZEROCOPY; 172 force_copy = flags & XDP_COPY; 173 174 if (force_zc && force_copy) 175 return -EINVAL; 176 177 if (xsk_get_pool_from_qid(netdev, queue_id)) 178 return -EBUSY; 179 180 pool->netdev = netdev; 181 pool->queue_id = queue_id; 182 err = xsk_reg_pool_at_qid(netdev, pool, queue_id); 183 if (err) 184 return err; 185 186 if (flags & XDP_USE_SG) 187 pool->umem->flags |= XDP_UMEM_SG_FLAG; 188 189 if (flags & XDP_USE_NEED_WAKEUP) 190 pool->uses_need_wakeup = true; 191 /* Tx needs to be explicitly woken up the first time. Also 192 * for supporting drivers that do not implement this 193 * feature. They will always have to call sendto() or poll(). 194 */ 195 pool->cached_need_wakeup = XDP_WAKEUP_TX; 196 197 dev_hold(netdev); 198 199 if (force_copy) 200 /* For copy-mode, we are done. */ 201 return 0; 202 203 if ((netdev->xdp_features & NETDEV_XDP_ACT_ZC) != NETDEV_XDP_ACT_ZC) { 204 err = -EOPNOTSUPP; 205 goto err_unreg_pool; 206 } 207 208 if (netdev->xdp_zc_max_segs == 1 && (flags & XDP_USE_SG)) { 209 err = -EOPNOTSUPP; 210 goto err_unreg_pool; 211 } 212 213 if (dev_get_min_mp_channel_count(netdev)) { 214 err = -EBUSY; 215 goto err_unreg_pool; 216 } 217 218 bpf.command = XDP_SETUP_XSK_POOL; 219 bpf.xsk.pool = pool; 220 bpf.xsk.queue_id = queue_id; 221 222 netdev_ops_assert_locked(netdev); 223 err = netdev->netdev_ops->ndo_bpf(netdev, &bpf); 224 if (err) 225 goto err_unreg_pool; 226 227 if (!pool->dma_pages) { 228 WARN(1, "Driver did not DMA map zero-copy buffers"); 229 err = -EINVAL; 230 goto err_unreg_xsk; 231 } 232 pool->umem->zc = true; 233 pool->xdp_zc_max_segs = netdev->xdp_zc_max_segs; 234 return 0; 235 236 err_unreg_xsk: 237 xp_disable_drv_zc(pool); 238 err_unreg_pool: 239 if (!force_zc) 240 err = 0; /* fallback to copy mode */ 241 if (err) { 242 xsk_clear_pool_at_qid(netdev, queue_id); 243 dev_put(netdev); 244 } 245 return err; 246 } 247 248 int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_sock *umem_xs, 249 struct net_device *dev, u16 queue_id) 250 { 251 u16 flags; 252 struct xdp_umem *umem = umem_xs->umem; 253 254 /* One fill and completion ring required for each queue id. */ 255 if (!pool->fq || !pool->cq) 256 return -EINVAL; 257 258 flags = umem->zc ? XDP_ZEROCOPY : XDP_COPY; 259 if (umem_xs->pool->uses_need_wakeup) 260 flags |= XDP_USE_NEED_WAKEUP; 261 262 return xp_assign_dev(pool, dev, queue_id, flags); 263 } 264 265 void xp_clear_dev(struct xsk_buff_pool *pool) 266 { 267 struct net_device *netdev = pool->netdev; 268 269 if (!pool->netdev) 270 return; 271 272 netdev_lock_ops(netdev); 273 xp_disable_drv_zc(pool); 274 xsk_clear_pool_at_qid(pool->netdev, pool->queue_id); 275 pool->netdev = NULL; 276 netdev_unlock_ops(netdev); 277 dev_put(netdev); 278 } 279 280 static void xp_release_deferred(struct work_struct *work) 281 { 282 struct xsk_buff_pool *pool = container_of(work, struct xsk_buff_pool, 283 work); 284 285 rtnl_lock(); 286 xp_clear_dev(pool); 287 rtnl_unlock(); 288 289 if (pool->fq) { 290 xskq_destroy(pool->fq); 291 pool->fq = NULL; 292 } 293 294 if (pool->cq) { 295 xskq_destroy(pool->cq); 296 pool->cq = NULL; 297 } 298 299 xdp_put_umem(pool->umem, false); 300 xp_destroy(pool); 301 } 302 303 void xp_get_pool(struct xsk_buff_pool *pool) 304 { 305 refcount_inc(&pool->users); 306 } 307 308 bool xp_put_pool(struct xsk_buff_pool *pool) 309 { 310 if (!pool) 311 return false; 312 313 if (refcount_dec_and_test(&pool->users)) { 314 INIT_WORK(&pool->work, xp_release_deferred); 315 schedule_work(&pool->work); 316 return true; 317 } 318 319 return false; 320 } 321 322 static struct xsk_dma_map *xp_find_dma_map(struct xsk_buff_pool *pool) 323 { 324 struct xsk_dma_map *dma_map; 325 326 list_for_each_entry(dma_map, &pool->umem->xsk_dma_list, list) { 327 if (dma_map->netdev == pool->netdev) 328 return dma_map; 329 } 330 331 return NULL; 332 } 333 334 static struct xsk_dma_map *xp_create_dma_map(struct device *dev, struct net_device *netdev, 335 u32 nr_pages, struct xdp_umem *umem) 336 { 337 struct xsk_dma_map *dma_map; 338 339 dma_map = kzalloc(sizeof(*dma_map), GFP_KERNEL); 340 if (!dma_map) 341 return NULL; 342 343 dma_map->dma_pages = kvcalloc(nr_pages, sizeof(*dma_map->dma_pages), GFP_KERNEL); 344 if (!dma_map->dma_pages) { 345 kfree(dma_map); 346 return NULL; 347 } 348 349 dma_map->netdev = netdev; 350 dma_map->dev = dev; 351 dma_map->dma_pages_cnt = nr_pages; 352 refcount_set(&dma_map->users, 1); 353 list_add(&dma_map->list, &umem->xsk_dma_list); 354 return dma_map; 355 } 356 357 static void xp_destroy_dma_map(struct xsk_dma_map *dma_map) 358 { 359 list_del(&dma_map->list); 360 kvfree(dma_map->dma_pages); 361 kfree(dma_map); 362 } 363 364 static void __xp_dma_unmap(struct xsk_dma_map *dma_map, unsigned long attrs) 365 { 366 dma_addr_t *dma; 367 u32 i; 368 369 for (i = 0; i < dma_map->dma_pages_cnt; i++) { 370 dma = &dma_map->dma_pages[i]; 371 if (*dma) { 372 *dma &= ~XSK_NEXT_PG_CONTIG_MASK; 373 dma_unmap_page_attrs(dma_map->dev, *dma, PAGE_SIZE, 374 DMA_BIDIRECTIONAL, attrs); 375 *dma = 0; 376 } 377 } 378 379 xp_destroy_dma_map(dma_map); 380 } 381 382 void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs) 383 { 384 struct xsk_dma_map *dma_map; 385 386 if (!pool->dma_pages) 387 return; 388 389 dma_map = xp_find_dma_map(pool); 390 if (!dma_map) { 391 WARN(1, "Could not find dma_map for device"); 392 return; 393 } 394 395 if (refcount_dec_and_test(&dma_map->users)) 396 __xp_dma_unmap(dma_map, attrs); 397 398 kvfree(pool->dma_pages); 399 pool->dma_pages = NULL; 400 pool->dma_pages_cnt = 0; 401 pool->dev = NULL; 402 } 403 EXPORT_SYMBOL(xp_dma_unmap); 404 405 static void xp_check_dma_contiguity(struct xsk_dma_map *dma_map) 406 { 407 u32 i; 408 409 for (i = 0; i < dma_map->dma_pages_cnt - 1; i++) { 410 if (dma_map->dma_pages[i] + PAGE_SIZE == dma_map->dma_pages[i + 1]) 411 dma_map->dma_pages[i] |= XSK_NEXT_PG_CONTIG_MASK; 412 else 413 dma_map->dma_pages[i] &= ~XSK_NEXT_PG_CONTIG_MASK; 414 } 415 } 416 417 static int xp_init_dma_info(struct xsk_buff_pool *pool, struct xsk_dma_map *dma_map) 418 { 419 if (!pool->unaligned) { 420 u32 i; 421 422 for (i = 0; i < pool->heads_cnt; i++) { 423 struct xdp_buff_xsk *xskb = &pool->heads[i]; 424 u64 orig_addr; 425 426 orig_addr = xskb->xdp.data_hard_start - pool->addrs - pool->headroom; 427 xp_init_xskb_dma(xskb, pool, dma_map->dma_pages, orig_addr); 428 } 429 } 430 431 pool->dma_pages = kvcalloc(dma_map->dma_pages_cnt, sizeof(*pool->dma_pages), GFP_KERNEL); 432 if (!pool->dma_pages) 433 return -ENOMEM; 434 435 pool->dev = dma_map->dev; 436 pool->dma_pages_cnt = dma_map->dma_pages_cnt; 437 memcpy(pool->dma_pages, dma_map->dma_pages, 438 pool->dma_pages_cnt * sizeof(*pool->dma_pages)); 439 440 return 0; 441 } 442 443 int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev, 444 unsigned long attrs, struct page **pages, u32 nr_pages) 445 { 446 struct xsk_dma_map *dma_map; 447 dma_addr_t dma; 448 int err; 449 u32 i; 450 451 dma_map = xp_find_dma_map(pool); 452 if (dma_map) { 453 err = xp_init_dma_info(pool, dma_map); 454 if (err) 455 return err; 456 457 refcount_inc(&dma_map->users); 458 return 0; 459 } 460 461 dma_map = xp_create_dma_map(dev, pool->netdev, nr_pages, pool->umem); 462 if (!dma_map) 463 return -ENOMEM; 464 465 for (i = 0; i < dma_map->dma_pages_cnt; i++) { 466 dma = dma_map_page_attrs(dev, pages[i], 0, PAGE_SIZE, 467 DMA_BIDIRECTIONAL, attrs); 468 if (dma_mapping_error(dev, dma)) { 469 __xp_dma_unmap(dma_map, attrs); 470 return -ENOMEM; 471 } 472 dma_map->dma_pages[i] = dma; 473 } 474 475 if (pool->unaligned) 476 xp_check_dma_contiguity(dma_map); 477 478 err = xp_init_dma_info(pool, dma_map); 479 if (err) { 480 __xp_dma_unmap(dma_map, attrs); 481 return err; 482 } 483 484 return 0; 485 } 486 EXPORT_SYMBOL(xp_dma_map); 487 488 static bool xp_addr_crosses_non_contig_pg(struct xsk_buff_pool *pool, 489 u64 addr) 490 { 491 return xp_desc_crosses_non_contig_pg(pool, addr, pool->chunk_size); 492 } 493 494 static bool xp_check_unaligned(struct xsk_buff_pool *pool, u64 *addr) 495 { 496 *addr = xp_unaligned_extract_addr(*addr); 497 if (*addr >= pool->addrs_cnt || 498 *addr + pool->chunk_size > pool->addrs_cnt || 499 xp_addr_crosses_non_contig_pg(pool, *addr)) 500 return false; 501 return true; 502 } 503 504 static bool xp_check_aligned(struct xsk_buff_pool *pool, u64 *addr) 505 { 506 *addr = xp_aligned_extract_addr(pool, *addr); 507 return *addr < pool->addrs_cnt; 508 } 509 510 static struct xdp_buff_xsk *xp_get_xskb(struct xsk_buff_pool *pool, u64 addr) 511 { 512 struct xdp_buff_xsk *xskb; 513 514 if (pool->unaligned) { 515 xskb = pool->free_heads[--pool->free_heads_cnt]; 516 xp_init_xskb_addr(xskb, pool, addr); 517 if (pool->dma_pages) 518 xp_init_xskb_dma(xskb, pool, pool->dma_pages, addr); 519 } else { 520 xskb = &pool->heads[xp_aligned_extract_idx(pool, addr)]; 521 } 522 523 return xskb; 524 } 525 526 static struct xdp_buff_xsk *__xp_alloc(struct xsk_buff_pool *pool) 527 { 528 struct xdp_buff_xsk *xskb; 529 u64 addr; 530 bool ok; 531 532 if (pool->free_heads_cnt == 0) 533 return NULL; 534 535 for (;;) { 536 if (!xskq_cons_peek_addr_unchecked(pool->fq, &addr)) { 537 pool->fq->queue_empty_descs++; 538 return NULL; 539 } 540 541 ok = pool->unaligned ? xp_check_unaligned(pool, &addr) : 542 xp_check_aligned(pool, &addr); 543 if (!ok) { 544 pool->fq->invalid_descs++; 545 xskq_cons_release(pool->fq); 546 continue; 547 } 548 break; 549 } 550 551 xskb = xp_get_xskb(pool, addr); 552 553 xskq_cons_release(pool->fq); 554 return xskb; 555 } 556 557 struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool) 558 { 559 struct xdp_buff_xsk *xskb; 560 561 if (!pool->free_list_cnt) { 562 xskb = __xp_alloc(pool); 563 if (!xskb) 564 return NULL; 565 } else { 566 pool->free_list_cnt--; 567 xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk, 568 list_node); 569 list_del_init(&xskb->list_node); 570 } 571 572 xskb->xdp.data = xskb->xdp.data_hard_start + XDP_PACKET_HEADROOM; 573 xskb->xdp.data_meta = xskb->xdp.data; 574 xskb->xdp.flags = 0; 575 576 if (pool->dev) 577 xp_dma_sync_for_device(pool, xskb->dma, pool->frame_len); 578 579 return &xskb->xdp; 580 } 581 EXPORT_SYMBOL(xp_alloc); 582 583 static u32 xp_alloc_new_from_fq(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max) 584 { 585 u32 i, cached_cons, nb_entries; 586 587 if (max > pool->free_heads_cnt) 588 max = pool->free_heads_cnt; 589 max = xskq_cons_nb_entries(pool->fq, max); 590 591 cached_cons = pool->fq->cached_cons; 592 nb_entries = max; 593 i = max; 594 while (i--) { 595 struct xdp_buff_xsk *xskb; 596 u64 addr; 597 bool ok; 598 599 __xskq_cons_read_addr_unchecked(pool->fq, cached_cons++, &addr); 600 601 ok = pool->unaligned ? xp_check_unaligned(pool, &addr) : 602 xp_check_aligned(pool, &addr); 603 if (unlikely(!ok)) { 604 pool->fq->invalid_descs++; 605 nb_entries--; 606 continue; 607 } 608 609 xskb = xp_get_xskb(pool, addr); 610 611 *xdp = &xskb->xdp; 612 xdp++; 613 } 614 615 xskq_cons_release_n(pool->fq, max); 616 return nb_entries; 617 } 618 619 static u32 xp_alloc_reused(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 nb_entries) 620 { 621 struct xdp_buff_xsk *xskb; 622 u32 i; 623 624 nb_entries = min_t(u32, nb_entries, pool->free_list_cnt); 625 626 i = nb_entries; 627 while (i--) { 628 xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk, list_node); 629 list_del_init(&xskb->list_node); 630 631 *xdp = &xskb->xdp; 632 xdp++; 633 } 634 pool->free_list_cnt -= nb_entries; 635 636 return nb_entries; 637 } 638 639 static u32 xp_alloc_slow(struct xsk_buff_pool *pool, struct xdp_buff **xdp, 640 u32 max) 641 { 642 int i; 643 644 for (i = 0; i < max; i++) { 645 struct xdp_buff *buff; 646 647 buff = xp_alloc(pool); 648 if (unlikely(!buff)) 649 return i; 650 *xdp = buff; 651 xdp++; 652 } 653 654 return max; 655 } 656 657 u32 xp_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max) 658 { 659 u32 nb_entries1 = 0, nb_entries2; 660 661 if (unlikely(pool->dev && dma_dev_need_sync(pool->dev))) 662 return xp_alloc_slow(pool, xdp, max); 663 664 if (unlikely(pool->free_list_cnt)) { 665 nb_entries1 = xp_alloc_reused(pool, xdp, max); 666 if (nb_entries1 == max) 667 return nb_entries1; 668 669 max -= nb_entries1; 670 xdp += nb_entries1; 671 } 672 673 nb_entries2 = xp_alloc_new_from_fq(pool, xdp, max); 674 if (!nb_entries2) 675 pool->fq->queue_empty_descs++; 676 677 return nb_entries1 + nb_entries2; 678 } 679 EXPORT_SYMBOL(xp_alloc_batch); 680 681 bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count) 682 { 683 u32 req_count, avail_count; 684 685 if (pool->free_list_cnt >= count) 686 return true; 687 688 req_count = count - pool->free_list_cnt; 689 avail_count = xskq_cons_nb_entries(pool->fq, req_count); 690 if (!avail_count) 691 pool->fq->queue_empty_descs++; 692 693 return avail_count >= req_count; 694 } 695 EXPORT_SYMBOL(xp_can_alloc); 696 697 void xp_free(struct xdp_buff_xsk *xskb) 698 { 699 if (!list_empty(&xskb->list_node)) 700 return; 701 702 xskb->pool->free_list_cnt++; 703 list_add(&xskb->list_node, &xskb->pool->free_list); 704 } 705 EXPORT_SYMBOL(xp_free); 706 707 static u64 __xp_raw_get_addr(const struct xsk_buff_pool *pool, u64 addr) 708 { 709 return pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr; 710 } 711 712 static void *__xp_raw_get_data(const struct xsk_buff_pool *pool, u64 addr) 713 { 714 return pool->addrs + addr; 715 } 716 717 void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr) 718 { 719 return __xp_raw_get_data(pool, __xp_raw_get_addr(pool, addr)); 720 } 721 EXPORT_SYMBOL(xp_raw_get_data); 722 723 static dma_addr_t __xp_raw_get_dma(const struct xsk_buff_pool *pool, u64 addr) 724 { 725 return (pool->dma_pages[addr >> PAGE_SHIFT] & 726 ~XSK_NEXT_PG_CONTIG_MASK) + 727 (addr & ~PAGE_MASK); 728 } 729 730 dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr) 731 { 732 return __xp_raw_get_dma(pool, __xp_raw_get_addr(pool, addr)); 733 } 734 EXPORT_SYMBOL(xp_raw_get_dma); 735 736 /** 737 * xp_raw_get_ctx - get &xdp_desc context 738 * @pool: XSk buff pool desc address belongs to 739 * @addr: desc address (from userspace) 740 * 741 * Helper for getting desc's DMA address and metadata pointer, if present. 742 * Saves one call on hotpath, double calculation of the actual address, 743 * and inline checks for metadata presence and sanity. 744 * 745 * Return: new &xdp_desc_ctx struct containing desc's DMA address and metadata 746 * pointer, if it is present and valid (initialized to %NULL otherwise). 747 */ 748 struct xdp_desc_ctx xp_raw_get_ctx(const struct xsk_buff_pool *pool, u64 addr) 749 { 750 struct xdp_desc_ctx ret; 751 752 addr = __xp_raw_get_addr(pool, addr); 753 754 ret.dma = __xp_raw_get_dma(pool, addr); 755 ret.meta = __xsk_buff_get_metadata(pool, __xp_raw_get_data(pool, addr)); 756 757 return ret; 758 } 759 EXPORT_SYMBOL(xp_raw_get_ctx); 760