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