1 /* 2 * Copyright (C) 2017-2018 Netronome Systems, Inc. 3 * 4 * This software is licensed under the GNU General License Version 2, 5 * June 1991 as shown in the file COPYING in the top-level directory of this 6 * source tree. 7 * 8 * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" 9 * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, 10 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 11 * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE 12 * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME 13 * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 14 */ 15 16 #include <linux/bpf.h> 17 #include <linux/bpf_verifier.h> 18 #include <linux/bug.h> 19 #include <linux/kdev_t.h> 20 #include <linux/list.h> 21 #include <linux/lockdep.h> 22 #include <linux/netdevice.h> 23 #include <linux/printk.h> 24 #include <linux/proc_ns.h> 25 #include <linux/rhashtable.h> 26 #include <linux/rtnetlink.h> 27 #include <linux/rwsem.h> 28 29 /* Protects offdevs, members of bpf_offload_netdev and offload members 30 * of all progs. 31 * RTNL lock cannot be taken when holding this lock. 32 */ 33 static DECLARE_RWSEM(bpf_devs_lock); 34 35 struct bpf_offload_dev { 36 const struct bpf_prog_offload_ops *ops; 37 struct list_head netdevs; 38 void *priv; 39 }; 40 41 struct bpf_offload_netdev { 42 struct rhash_head l; 43 struct net_device *netdev; 44 struct bpf_offload_dev *offdev; /* NULL when bound-only */ 45 struct list_head progs; 46 struct list_head maps; 47 struct list_head offdev_netdevs; 48 }; 49 50 static const struct rhashtable_params offdevs_params = { 51 .nelem_hint = 4, 52 .key_len = sizeof(struct net_device *), 53 .key_offset = offsetof(struct bpf_offload_netdev, netdev), 54 .head_offset = offsetof(struct bpf_offload_netdev, l), 55 .automatic_shrinking = true, 56 }; 57 58 static struct rhashtable offdevs; 59 60 static int bpf_dev_offload_check(struct net_device *netdev) 61 { 62 if (!netdev) 63 return -EINVAL; 64 if (!netdev->netdev_ops->ndo_bpf) 65 return -EOPNOTSUPP; 66 return 0; 67 } 68 69 static struct bpf_offload_netdev * 70 bpf_offload_find_netdev(struct net_device *netdev) 71 { 72 lockdep_assert_held(&bpf_devs_lock); 73 74 return rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params); 75 } 76 77 static int __bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev, 78 struct net_device *netdev) 79 { 80 struct bpf_offload_netdev *ondev; 81 int err; 82 83 ondev = kzalloc(sizeof(*ondev), GFP_KERNEL); 84 if (!ondev) 85 return -ENOMEM; 86 87 ondev->netdev = netdev; 88 ondev->offdev = offdev; 89 INIT_LIST_HEAD(&ondev->progs); 90 INIT_LIST_HEAD(&ondev->maps); 91 92 err = rhashtable_insert_fast(&offdevs, &ondev->l, offdevs_params); 93 if (err) { 94 netdev_warn(netdev, "failed to register for BPF offload\n"); 95 goto err_free; 96 } 97 98 if (offdev) 99 list_add(&ondev->offdev_netdevs, &offdev->netdevs); 100 return 0; 101 102 err_free: 103 kfree(ondev); 104 return err; 105 } 106 107 static void __bpf_prog_offload_destroy(struct bpf_prog *prog) 108 { 109 struct bpf_prog_offload *offload = prog->aux->offload; 110 111 if (offload->dev_state) 112 offload->offdev->ops->destroy(prog); 113 114 /* Make sure BPF_PROG_GET_NEXT_ID can't find this dead program */ 115 bpf_prog_free_id(prog, true); 116 117 list_del_init(&offload->offloads); 118 kfree(offload); 119 prog->aux->offload = NULL; 120 } 121 122 static int bpf_map_offload_ndo(struct bpf_offloaded_map *offmap, 123 enum bpf_netdev_command cmd) 124 { 125 struct netdev_bpf data = {}; 126 struct net_device *netdev; 127 128 ASSERT_RTNL(); 129 130 data.command = cmd; 131 data.offmap = offmap; 132 /* Caller must make sure netdev is valid */ 133 netdev = offmap->netdev; 134 135 return netdev->netdev_ops->ndo_bpf(netdev, &data); 136 } 137 138 static void __bpf_map_offload_destroy(struct bpf_offloaded_map *offmap) 139 { 140 WARN_ON(bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_FREE)); 141 /* Make sure BPF_MAP_GET_NEXT_ID can't find this dead map */ 142 bpf_map_free_id(&offmap->map, true); 143 list_del_init(&offmap->offloads); 144 offmap->netdev = NULL; 145 } 146 147 static void __bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev, 148 struct net_device *netdev) 149 { 150 struct bpf_offload_netdev *ondev, *altdev = NULL; 151 struct bpf_offloaded_map *offmap, *mtmp; 152 struct bpf_prog_offload *offload, *ptmp; 153 154 ASSERT_RTNL(); 155 156 ondev = rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params); 157 if (WARN_ON(!ondev)) 158 return; 159 160 WARN_ON(rhashtable_remove_fast(&offdevs, &ondev->l, offdevs_params)); 161 162 /* Try to move the objects to another netdev of the device */ 163 if (offdev) { 164 list_del(&ondev->offdev_netdevs); 165 altdev = list_first_entry_or_null(&offdev->netdevs, 166 struct bpf_offload_netdev, 167 offdev_netdevs); 168 } 169 170 if (altdev) { 171 list_for_each_entry(offload, &ondev->progs, offloads) 172 offload->netdev = altdev->netdev; 173 list_splice_init(&ondev->progs, &altdev->progs); 174 175 list_for_each_entry(offmap, &ondev->maps, offloads) 176 offmap->netdev = altdev->netdev; 177 list_splice_init(&ondev->maps, &altdev->maps); 178 } else { 179 list_for_each_entry_safe(offload, ptmp, &ondev->progs, offloads) 180 __bpf_prog_offload_destroy(offload->prog); 181 list_for_each_entry_safe(offmap, mtmp, &ondev->maps, offloads) 182 __bpf_map_offload_destroy(offmap); 183 } 184 185 WARN_ON(!list_empty(&ondev->progs)); 186 WARN_ON(!list_empty(&ondev->maps)); 187 kfree(ondev); 188 } 189 190 int bpf_prog_dev_bound_init(struct bpf_prog *prog, union bpf_attr *attr) 191 { 192 struct bpf_offload_netdev *ondev; 193 struct bpf_prog_offload *offload; 194 int err; 195 196 if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS && 197 attr->prog_type != BPF_PROG_TYPE_XDP) 198 return -EINVAL; 199 200 if (attr->prog_flags & ~BPF_F_XDP_DEV_BOUND_ONLY) 201 return -EINVAL; 202 203 if (attr->prog_type == BPF_PROG_TYPE_SCHED_CLS && 204 attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY) 205 return -EINVAL; 206 207 offload = kzalloc(sizeof(*offload), GFP_USER); 208 if (!offload) 209 return -ENOMEM; 210 211 offload->prog = prog; 212 213 offload->netdev = dev_get_by_index(current->nsproxy->net_ns, 214 attr->prog_ifindex); 215 err = bpf_dev_offload_check(offload->netdev); 216 if (err) 217 goto err_maybe_put; 218 219 prog->aux->offload_requested = !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY); 220 221 down_write(&bpf_devs_lock); 222 ondev = bpf_offload_find_netdev(offload->netdev); 223 if (!ondev) { 224 if (bpf_prog_is_offloaded(prog->aux)) { 225 err = -EINVAL; 226 goto err_unlock; 227 } 228 229 /* When only binding to the device, explicitly 230 * create an entry in the hashtable. 231 */ 232 err = __bpf_offload_dev_netdev_register(NULL, offload->netdev); 233 if (err) 234 goto err_unlock; 235 ondev = bpf_offload_find_netdev(offload->netdev); 236 } 237 offload->offdev = ondev->offdev; 238 prog->aux->offload = offload; 239 list_add_tail(&offload->offloads, &ondev->progs); 240 dev_put(offload->netdev); 241 up_write(&bpf_devs_lock); 242 243 return 0; 244 err_unlock: 245 up_write(&bpf_devs_lock); 246 err_maybe_put: 247 if (offload->netdev) 248 dev_put(offload->netdev); 249 kfree(offload); 250 return err; 251 } 252 253 int bpf_prog_offload_verifier_prep(struct bpf_prog *prog) 254 { 255 struct bpf_prog_offload *offload; 256 int ret = -ENODEV; 257 258 down_read(&bpf_devs_lock); 259 offload = prog->aux->offload; 260 if (offload) { 261 ret = offload->offdev->ops->prepare(prog); 262 offload->dev_state = !ret; 263 } 264 up_read(&bpf_devs_lock); 265 266 return ret; 267 } 268 269 int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env, 270 int insn_idx, int prev_insn_idx) 271 { 272 struct bpf_prog_offload *offload; 273 int ret = -ENODEV; 274 275 down_read(&bpf_devs_lock); 276 offload = env->prog->aux->offload; 277 if (offload) 278 ret = offload->offdev->ops->insn_hook(env, insn_idx, 279 prev_insn_idx); 280 up_read(&bpf_devs_lock); 281 282 return ret; 283 } 284 285 int bpf_prog_offload_finalize(struct bpf_verifier_env *env) 286 { 287 struct bpf_prog_offload *offload; 288 int ret = -ENODEV; 289 290 down_read(&bpf_devs_lock); 291 offload = env->prog->aux->offload; 292 if (offload) { 293 if (offload->offdev->ops->finalize) 294 ret = offload->offdev->ops->finalize(env); 295 else 296 ret = 0; 297 } 298 up_read(&bpf_devs_lock); 299 300 return ret; 301 } 302 303 void 304 bpf_prog_offload_replace_insn(struct bpf_verifier_env *env, u32 off, 305 struct bpf_insn *insn) 306 { 307 const struct bpf_prog_offload_ops *ops; 308 struct bpf_prog_offload *offload; 309 int ret = -EOPNOTSUPP; 310 311 down_read(&bpf_devs_lock); 312 offload = env->prog->aux->offload; 313 if (offload) { 314 ops = offload->offdev->ops; 315 if (!offload->opt_failed && ops->replace_insn) 316 ret = ops->replace_insn(env, off, insn); 317 offload->opt_failed |= ret; 318 } 319 up_read(&bpf_devs_lock); 320 } 321 322 void 323 bpf_prog_offload_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt) 324 { 325 struct bpf_prog_offload *offload; 326 int ret = -EOPNOTSUPP; 327 328 down_read(&bpf_devs_lock); 329 offload = env->prog->aux->offload; 330 if (offload) { 331 if (!offload->opt_failed && offload->offdev->ops->remove_insns) 332 ret = offload->offdev->ops->remove_insns(env, off, cnt); 333 offload->opt_failed |= ret; 334 } 335 up_read(&bpf_devs_lock); 336 } 337 338 void bpf_prog_dev_bound_destroy(struct bpf_prog *prog) 339 { 340 struct bpf_offload_netdev *ondev; 341 struct net_device *netdev; 342 343 rtnl_lock(); 344 down_write(&bpf_devs_lock); 345 if (prog->aux->offload) { 346 list_del_init(&prog->aux->offload->offloads); 347 348 netdev = prog->aux->offload->netdev; 349 __bpf_prog_offload_destroy(prog); 350 351 ondev = bpf_offload_find_netdev(netdev); 352 if (!ondev->offdev && list_empty(&ondev->progs)) 353 __bpf_offload_dev_netdev_unregister(NULL, netdev); 354 } 355 up_write(&bpf_devs_lock); 356 rtnl_unlock(); 357 } 358 359 static int bpf_prog_offload_translate(struct bpf_prog *prog) 360 { 361 struct bpf_prog_offload *offload; 362 int ret = -ENODEV; 363 364 down_read(&bpf_devs_lock); 365 offload = prog->aux->offload; 366 if (offload) 367 ret = offload->offdev->ops->translate(prog); 368 up_read(&bpf_devs_lock); 369 370 return ret; 371 } 372 373 static unsigned int bpf_prog_warn_on_exec(const void *ctx, 374 const struct bpf_insn *insn) 375 { 376 WARN(1, "attempt to execute device eBPF program on the host!"); 377 return 0; 378 } 379 380 int bpf_prog_offload_compile(struct bpf_prog *prog) 381 { 382 prog->bpf_func = bpf_prog_warn_on_exec; 383 384 return bpf_prog_offload_translate(prog); 385 } 386 387 struct ns_get_path_bpf_prog_args { 388 struct bpf_prog *prog; 389 struct bpf_prog_info *info; 390 }; 391 392 static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data) 393 { 394 struct ns_get_path_bpf_prog_args *args = private_data; 395 struct bpf_prog_aux *aux = args->prog->aux; 396 struct ns_common *ns; 397 struct net *net; 398 399 rtnl_lock(); 400 down_read(&bpf_devs_lock); 401 402 if (aux->offload) { 403 args->info->ifindex = aux->offload->netdev->ifindex; 404 net = dev_net(aux->offload->netdev); 405 get_net(net); 406 ns = &net->ns; 407 } else { 408 args->info->ifindex = 0; 409 ns = NULL; 410 } 411 412 up_read(&bpf_devs_lock); 413 rtnl_unlock(); 414 415 return ns; 416 } 417 418 int bpf_prog_offload_info_fill(struct bpf_prog_info *info, 419 struct bpf_prog *prog) 420 { 421 struct ns_get_path_bpf_prog_args args = { 422 .prog = prog, 423 .info = info, 424 }; 425 struct bpf_prog_aux *aux = prog->aux; 426 struct inode *ns_inode; 427 struct path ns_path; 428 char __user *uinsns; 429 int res; 430 u32 ulen; 431 432 res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args); 433 if (res) { 434 if (!info->ifindex) 435 return -ENODEV; 436 return res; 437 } 438 439 down_read(&bpf_devs_lock); 440 441 if (!aux->offload) { 442 up_read(&bpf_devs_lock); 443 return -ENODEV; 444 } 445 446 ulen = info->jited_prog_len; 447 info->jited_prog_len = aux->offload->jited_len; 448 if (info->jited_prog_len && ulen) { 449 uinsns = u64_to_user_ptr(info->jited_prog_insns); 450 ulen = min_t(u32, info->jited_prog_len, ulen); 451 if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) { 452 up_read(&bpf_devs_lock); 453 return -EFAULT; 454 } 455 } 456 457 up_read(&bpf_devs_lock); 458 459 ns_inode = ns_path.dentry->d_inode; 460 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 461 info->netns_ino = ns_inode->i_ino; 462 path_put(&ns_path); 463 464 return 0; 465 } 466 467 const struct bpf_prog_ops bpf_offload_prog_ops = { 468 }; 469 470 struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr) 471 { 472 struct net *net = current->nsproxy->net_ns; 473 struct bpf_offload_netdev *ondev; 474 struct bpf_offloaded_map *offmap; 475 int err; 476 477 if (!capable(CAP_SYS_ADMIN)) 478 return ERR_PTR(-EPERM); 479 if (attr->map_type != BPF_MAP_TYPE_ARRAY && 480 attr->map_type != BPF_MAP_TYPE_HASH) 481 return ERR_PTR(-EINVAL); 482 483 offmap = bpf_map_area_alloc(sizeof(*offmap), NUMA_NO_NODE); 484 if (!offmap) 485 return ERR_PTR(-ENOMEM); 486 487 bpf_map_init_from_attr(&offmap->map, attr); 488 489 rtnl_lock(); 490 down_write(&bpf_devs_lock); 491 offmap->netdev = __dev_get_by_index(net, attr->map_ifindex); 492 err = bpf_dev_offload_check(offmap->netdev); 493 if (err) 494 goto err_unlock; 495 496 ondev = bpf_offload_find_netdev(offmap->netdev); 497 if (!ondev) { 498 err = -EINVAL; 499 goto err_unlock; 500 } 501 502 err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC); 503 if (err) 504 goto err_unlock; 505 506 list_add_tail(&offmap->offloads, &ondev->maps); 507 up_write(&bpf_devs_lock); 508 rtnl_unlock(); 509 510 return &offmap->map; 511 512 err_unlock: 513 up_write(&bpf_devs_lock); 514 rtnl_unlock(); 515 bpf_map_area_free(offmap); 516 return ERR_PTR(err); 517 } 518 519 void bpf_map_offload_map_free(struct bpf_map *map) 520 { 521 struct bpf_offloaded_map *offmap = map_to_offmap(map); 522 523 rtnl_lock(); 524 down_write(&bpf_devs_lock); 525 if (offmap->netdev) 526 __bpf_map_offload_destroy(offmap); 527 up_write(&bpf_devs_lock); 528 rtnl_unlock(); 529 530 bpf_map_area_free(offmap); 531 } 532 533 int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value) 534 { 535 struct bpf_offloaded_map *offmap = map_to_offmap(map); 536 int ret = -ENODEV; 537 538 down_read(&bpf_devs_lock); 539 if (offmap->netdev) 540 ret = offmap->dev_ops->map_lookup_elem(offmap, key, value); 541 up_read(&bpf_devs_lock); 542 543 return ret; 544 } 545 546 int bpf_map_offload_update_elem(struct bpf_map *map, 547 void *key, void *value, u64 flags) 548 { 549 struct bpf_offloaded_map *offmap = map_to_offmap(map); 550 int ret = -ENODEV; 551 552 if (unlikely(flags > BPF_EXIST)) 553 return -EINVAL; 554 555 down_read(&bpf_devs_lock); 556 if (offmap->netdev) 557 ret = offmap->dev_ops->map_update_elem(offmap, key, value, 558 flags); 559 up_read(&bpf_devs_lock); 560 561 return ret; 562 } 563 564 int bpf_map_offload_delete_elem(struct bpf_map *map, void *key) 565 { 566 struct bpf_offloaded_map *offmap = map_to_offmap(map); 567 int ret = -ENODEV; 568 569 down_read(&bpf_devs_lock); 570 if (offmap->netdev) 571 ret = offmap->dev_ops->map_delete_elem(offmap, key); 572 up_read(&bpf_devs_lock); 573 574 return ret; 575 } 576 577 int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key) 578 { 579 struct bpf_offloaded_map *offmap = map_to_offmap(map); 580 int ret = -ENODEV; 581 582 down_read(&bpf_devs_lock); 583 if (offmap->netdev) 584 ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key); 585 up_read(&bpf_devs_lock); 586 587 return ret; 588 } 589 590 struct ns_get_path_bpf_map_args { 591 struct bpf_offloaded_map *offmap; 592 struct bpf_map_info *info; 593 }; 594 595 static struct ns_common *bpf_map_offload_info_fill_ns(void *private_data) 596 { 597 struct ns_get_path_bpf_map_args *args = private_data; 598 struct ns_common *ns; 599 struct net *net; 600 601 rtnl_lock(); 602 down_read(&bpf_devs_lock); 603 604 if (args->offmap->netdev) { 605 args->info->ifindex = args->offmap->netdev->ifindex; 606 net = dev_net(args->offmap->netdev); 607 get_net(net); 608 ns = &net->ns; 609 } else { 610 args->info->ifindex = 0; 611 ns = NULL; 612 } 613 614 up_read(&bpf_devs_lock); 615 rtnl_unlock(); 616 617 return ns; 618 } 619 620 int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map) 621 { 622 struct ns_get_path_bpf_map_args args = { 623 .offmap = map_to_offmap(map), 624 .info = info, 625 }; 626 struct inode *ns_inode; 627 struct path ns_path; 628 int res; 629 630 res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args); 631 if (res) { 632 if (!info->ifindex) 633 return -ENODEV; 634 return res; 635 } 636 637 ns_inode = ns_path.dentry->d_inode; 638 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 639 info->netns_ino = ns_inode->i_ino; 640 path_put(&ns_path); 641 642 return 0; 643 } 644 645 static bool __bpf_offload_dev_match(struct bpf_prog *prog, 646 struct net_device *netdev) 647 { 648 struct bpf_offload_netdev *ondev1, *ondev2; 649 struct bpf_prog_offload *offload; 650 651 if (!bpf_prog_is_dev_bound(prog->aux)) 652 return false; 653 654 offload = prog->aux->offload; 655 if (!offload) 656 return false; 657 if (offload->netdev == netdev) 658 return true; 659 660 ondev1 = bpf_offload_find_netdev(offload->netdev); 661 ondev2 = bpf_offload_find_netdev(netdev); 662 663 return ondev1 && ondev2 && ondev1->offdev == ondev2->offdev; 664 } 665 666 bool bpf_offload_dev_match(struct bpf_prog *prog, struct net_device *netdev) 667 { 668 bool ret; 669 670 down_read(&bpf_devs_lock); 671 ret = __bpf_offload_dev_match(prog, netdev); 672 up_read(&bpf_devs_lock); 673 674 return ret; 675 } 676 EXPORT_SYMBOL_GPL(bpf_offload_dev_match); 677 678 bool bpf_offload_prog_map_match(struct bpf_prog *prog, struct bpf_map *map) 679 { 680 struct bpf_offloaded_map *offmap; 681 bool ret; 682 683 if (!bpf_map_is_offloaded(map)) 684 return bpf_map_offload_neutral(map); 685 offmap = map_to_offmap(map); 686 687 down_read(&bpf_devs_lock); 688 ret = __bpf_offload_dev_match(prog, offmap->netdev); 689 up_read(&bpf_devs_lock); 690 691 return ret; 692 } 693 694 int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev, 695 struct net_device *netdev) 696 { 697 int err; 698 699 down_write(&bpf_devs_lock); 700 err = __bpf_offload_dev_netdev_register(offdev, netdev); 701 up_write(&bpf_devs_lock); 702 return err; 703 } 704 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_register); 705 706 void bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev, 707 struct net_device *netdev) 708 { 709 down_write(&bpf_devs_lock); 710 __bpf_offload_dev_netdev_unregister(offdev, netdev); 711 up_write(&bpf_devs_lock); 712 } 713 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_unregister); 714 715 struct bpf_offload_dev * 716 bpf_offload_dev_create(const struct bpf_prog_offload_ops *ops, void *priv) 717 { 718 struct bpf_offload_dev *offdev; 719 720 offdev = kzalloc(sizeof(*offdev), GFP_KERNEL); 721 if (!offdev) 722 return ERR_PTR(-ENOMEM); 723 724 offdev->ops = ops; 725 offdev->priv = priv; 726 INIT_LIST_HEAD(&offdev->netdevs); 727 728 return offdev; 729 } 730 EXPORT_SYMBOL_GPL(bpf_offload_dev_create); 731 732 void bpf_offload_dev_destroy(struct bpf_offload_dev *offdev) 733 { 734 WARN_ON(!list_empty(&offdev->netdevs)); 735 kfree(offdev); 736 } 737 EXPORT_SYMBOL_GPL(bpf_offload_dev_destroy); 738 739 void *bpf_offload_dev_priv(struct bpf_offload_dev *offdev) 740 { 741 return offdev->priv; 742 } 743 EXPORT_SYMBOL_GPL(bpf_offload_dev_priv); 744 745 void bpf_dev_bound_netdev_unregister(struct net_device *dev) 746 { 747 struct bpf_offload_netdev *ondev; 748 749 ASSERT_RTNL(); 750 751 down_write(&bpf_devs_lock); 752 ondev = bpf_offload_find_netdev(dev); 753 if (ondev && !ondev->offdev) 754 __bpf_offload_dev_netdev_unregister(NULL, ondev->netdev); 755 up_write(&bpf_devs_lock); 756 } 757 758 int bpf_dev_bound_kfunc_check(struct bpf_verifier_log *log, 759 struct bpf_prog_aux *prog_aux) 760 { 761 if (!bpf_prog_is_dev_bound(prog_aux)) { 762 bpf_log(log, "metadata kfuncs require device-bound program\n"); 763 return -EINVAL; 764 } 765 766 if (bpf_prog_is_offloaded(prog_aux)) { 767 bpf_log(log, "metadata kfuncs can't be offloaded\n"); 768 return -EINVAL; 769 } 770 771 return 0; 772 } 773 774 void *bpf_dev_bound_resolve_kfunc(struct bpf_prog *prog, u32 func_id) 775 { 776 const struct xdp_metadata_ops *ops; 777 void *p = NULL; 778 779 /* We don't hold bpf_devs_lock while resolving several 780 * kfuncs and can race with the unregister_netdevice(). 781 * We rely on bpf_dev_bound_match() check at attach 782 * to render this program unusable. 783 */ 784 down_read(&bpf_devs_lock); 785 if (!prog->aux->offload) 786 goto out; 787 788 ops = prog->aux->offload->netdev->xdp_metadata_ops; 789 if (!ops) 790 goto out; 791 792 if (func_id == bpf_xdp_metadata_kfunc_id(XDP_METADATA_KFUNC_RX_TIMESTAMP)) 793 p = ops->xmo_rx_timestamp; 794 else if (func_id == bpf_xdp_metadata_kfunc_id(XDP_METADATA_KFUNC_RX_HASH)) 795 p = ops->xmo_rx_hash; 796 out: 797 up_read(&bpf_devs_lock); 798 799 return p; 800 } 801 802 static int __init bpf_offload_init(void) 803 { 804 return rhashtable_init(&offdevs, &offdevs_params); 805 } 806 807 late_initcall(bpf_offload_init); 808