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 #include <net/xdp.h> 29 30 /* Protects offdevs, members of bpf_offload_netdev and offload members 31 * of all progs. 32 * RTNL lock cannot be taken when holding this lock. 33 */ 34 static DECLARE_RWSEM(bpf_devs_lock); 35 36 struct bpf_offload_dev { 37 const struct bpf_prog_offload_ops *ops; 38 struct list_head netdevs; 39 void *priv; 40 }; 41 42 struct bpf_offload_netdev { 43 struct rhash_head l; 44 struct net_device *netdev; 45 struct bpf_offload_dev *offdev; /* NULL when bound-only */ 46 struct list_head progs; 47 struct list_head maps; 48 struct list_head offdev_netdevs; 49 }; 50 51 static const struct rhashtable_params offdevs_params = { 52 .nelem_hint = 4, 53 .key_len = sizeof(struct net_device *), 54 .key_offset = offsetof(struct bpf_offload_netdev, netdev), 55 .head_offset = offsetof(struct bpf_offload_netdev, l), 56 .automatic_shrinking = true, 57 }; 58 59 static struct rhashtable offdevs; 60 61 static int bpf_dev_offload_check(struct net_device *netdev) 62 { 63 if (!netdev) 64 return -EINVAL; 65 if (!netdev->netdev_ops->ndo_bpf) 66 return -EOPNOTSUPP; 67 return 0; 68 } 69 70 static struct bpf_offload_netdev * 71 bpf_offload_find_netdev(struct net_device *netdev) 72 { 73 lockdep_assert_held(&bpf_devs_lock); 74 75 return rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params); 76 } 77 78 static int __bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev, 79 struct net_device *netdev) 80 { 81 struct bpf_offload_netdev *ondev; 82 int err; 83 84 ondev = kzalloc(sizeof(*ondev), GFP_KERNEL); 85 if (!ondev) 86 return -ENOMEM; 87 88 ondev->netdev = netdev; 89 ondev->offdev = offdev; 90 INIT_LIST_HEAD(&ondev->progs); 91 INIT_LIST_HEAD(&ondev->maps); 92 93 err = rhashtable_insert_fast(&offdevs, &ondev->l, offdevs_params); 94 if (err) { 95 netdev_warn(netdev, "failed to register for BPF offload\n"); 96 goto err_free; 97 } 98 99 if (offdev) 100 list_add(&ondev->offdev_netdevs, &offdev->netdevs); 101 return 0; 102 103 err_free: 104 kfree(ondev); 105 return err; 106 } 107 108 static void __bpf_prog_offload_destroy(struct bpf_prog *prog) 109 { 110 struct bpf_prog_offload *offload = prog->aux->offload; 111 112 if (offload->dev_state) 113 offload->offdev->ops->destroy(prog); 114 115 list_del_init(&offload->offloads); 116 kfree(offload); 117 prog->aux->offload = NULL; 118 } 119 120 static int bpf_map_offload_ndo(struct bpf_offloaded_map *offmap, 121 enum bpf_netdev_command cmd) 122 { 123 struct netdev_bpf data = {}; 124 struct net_device *netdev; 125 126 ASSERT_RTNL(); 127 128 data.command = cmd; 129 data.offmap = offmap; 130 /* Caller must make sure netdev is valid */ 131 netdev = offmap->netdev; 132 133 return netdev->netdev_ops->ndo_bpf(netdev, &data); 134 } 135 136 static void __bpf_map_offload_destroy(struct bpf_offloaded_map *offmap) 137 { 138 WARN_ON(bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_FREE)); 139 /* Make sure BPF_MAP_GET_NEXT_ID can't find this dead map */ 140 bpf_map_free_id(&offmap->map); 141 list_del_init(&offmap->offloads); 142 offmap->netdev = NULL; 143 } 144 145 static void __bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev, 146 struct net_device *netdev) 147 { 148 struct bpf_offload_netdev *ondev, *altdev = NULL; 149 struct bpf_offloaded_map *offmap, *mtmp; 150 struct bpf_prog_offload *offload, *ptmp; 151 152 ASSERT_RTNL(); 153 154 ondev = rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params); 155 if (WARN_ON(!ondev)) 156 return; 157 158 WARN_ON(rhashtable_remove_fast(&offdevs, &ondev->l, offdevs_params)); 159 160 /* Try to move the objects to another netdev of the device */ 161 if (offdev) { 162 list_del(&ondev->offdev_netdevs); 163 altdev = list_first_entry_or_null(&offdev->netdevs, 164 struct bpf_offload_netdev, 165 offdev_netdevs); 166 } 167 168 if (altdev) { 169 list_for_each_entry(offload, &ondev->progs, offloads) 170 offload->netdev = altdev->netdev; 171 list_splice_init(&ondev->progs, &altdev->progs); 172 173 list_for_each_entry(offmap, &ondev->maps, offloads) 174 offmap->netdev = altdev->netdev; 175 list_splice_init(&ondev->maps, &altdev->maps); 176 } else { 177 list_for_each_entry_safe(offload, ptmp, &ondev->progs, offloads) 178 __bpf_prog_offload_destroy(offload->prog); 179 list_for_each_entry_safe(offmap, mtmp, &ondev->maps, offloads) 180 __bpf_map_offload_destroy(offmap); 181 } 182 183 WARN_ON(!list_empty(&ondev->progs)); 184 WARN_ON(!list_empty(&ondev->maps)); 185 kfree(ondev); 186 } 187 188 static int __bpf_prog_dev_bound_init(struct bpf_prog *prog, struct net_device *netdev) 189 { 190 struct bpf_offload_netdev *ondev; 191 struct bpf_prog_offload *offload; 192 int err; 193 194 offload = kzalloc(sizeof(*offload), GFP_USER); 195 if (!offload) 196 return -ENOMEM; 197 198 offload->prog = prog; 199 offload->netdev = netdev; 200 201 ondev = bpf_offload_find_netdev(offload->netdev); 202 if (!ondev) { 203 if (bpf_prog_is_offloaded(prog->aux)) { 204 err = -EINVAL; 205 goto err_free; 206 } 207 208 /* When only binding to the device, explicitly 209 * create an entry in the hashtable. 210 */ 211 err = __bpf_offload_dev_netdev_register(NULL, offload->netdev); 212 if (err) 213 goto err_free; 214 ondev = bpf_offload_find_netdev(offload->netdev); 215 } 216 offload->offdev = ondev->offdev; 217 prog->aux->offload = offload; 218 list_add_tail(&offload->offloads, &ondev->progs); 219 220 return 0; 221 err_free: 222 kfree(offload); 223 return err; 224 } 225 226 int bpf_prog_dev_bound_init(struct bpf_prog *prog, union bpf_attr *attr) 227 { 228 struct net_device *netdev; 229 int err; 230 231 if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS && 232 attr->prog_type != BPF_PROG_TYPE_XDP) 233 return -EINVAL; 234 235 if (attr->prog_flags & ~BPF_F_XDP_DEV_BOUND_ONLY) 236 return -EINVAL; 237 238 if (attr->prog_type == BPF_PROG_TYPE_SCHED_CLS && 239 attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY) 240 return -EINVAL; 241 242 netdev = dev_get_by_index(current->nsproxy->net_ns, attr->prog_ifindex); 243 if (!netdev) 244 return -EINVAL; 245 246 err = bpf_dev_offload_check(netdev); 247 if (err) 248 goto out; 249 250 prog->aux->offload_requested = !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY); 251 252 down_write(&bpf_devs_lock); 253 err = __bpf_prog_dev_bound_init(prog, netdev); 254 up_write(&bpf_devs_lock); 255 256 out: 257 dev_put(netdev); 258 return err; 259 } 260 261 int bpf_prog_dev_bound_inherit(struct bpf_prog *new_prog, struct bpf_prog *old_prog) 262 { 263 int err; 264 265 if (!bpf_prog_is_dev_bound(old_prog->aux)) 266 return 0; 267 268 if (bpf_prog_is_offloaded(old_prog->aux)) 269 return -EINVAL; 270 271 new_prog->aux->dev_bound = old_prog->aux->dev_bound; 272 new_prog->aux->offload_requested = old_prog->aux->offload_requested; 273 274 down_write(&bpf_devs_lock); 275 if (!old_prog->aux->offload) { 276 err = -EINVAL; 277 goto out; 278 } 279 280 err = __bpf_prog_dev_bound_init(new_prog, old_prog->aux->offload->netdev); 281 282 out: 283 up_write(&bpf_devs_lock); 284 return err; 285 } 286 287 int bpf_prog_offload_verifier_prep(struct bpf_prog *prog) 288 { 289 struct bpf_prog_offload *offload; 290 int ret = -ENODEV; 291 292 down_read(&bpf_devs_lock); 293 offload = prog->aux->offload; 294 if (offload) { 295 ret = offload->offdev->ops->prepare(prog); 296 offload->dev_state = !ret; 297 } 298 up_read(&bpf_devs_lock); 299 300 return ret; 301 } 302 303 int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env, 304 int insn_idx, int prev_insn_idx) 305 { 306 struct bpf_prog_offload *offload; 307 int ret = -ENODEV; 308 309 down_read(&bpf_devs_lock); 310 offload = env->prog->aux->offload; 311 if (offload) 312 ret = offload->offdev->ops->insn_hook(env, insn_idx, 313 prev_insn_idx); 314 up_read(&bpf_devs_lock); 315 316 return ret; 317 } 318 319 int bpf_prog_offload_finalize(struct bpf_verifier_env *env) 320 { 321 struct bpf_prog_offload *offload; 322 int ret = -ENODEV; 323 324 down_read(&bpf_devs_lock); 325 offload = env->prog->aux->offload; 326 if (offload) { 327 if (offload->offdev->ops->finalize) 328 ret = offload->offdev->ops->finalize(env); 329 else 330 ret = 0; 331 } 332 up_read(&bpf_devs_lock); 333 334 return ret; 335 } 336 337 void 338 bpf_prog_offload_replace_insn(struct bpf_verifier_env *env, u32 off, 339 struct bpf_insn *insn) 340 { 341 const struct bpf_prog_offload_ops *ops; 342 struct bpf_prog_offload *offload; 343 int ret = -EOPNOTSUPP; 344 345 down_read(&bpf_devs_lock); 346 offload = env->prog->aux->offload; 347 if (offload) { 348 ops = offload->offdev->ops; 349 if (!offload->opt_failed && ops->replace_insn) 350 ret = ops->replace_insn(env, off, insn); 351 offload->opt_failed |= ret; 352 } 353 up_read(&bpf_devs_lock); 354 } 355 356 void 357 bpf_prog_offload_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt) 358 { 359 struct bpf_prog_offload *offload; 360 int ret = -EOPNOTSUPP; 361 362 down_read(&bpf_devs_lock); 363 offload = env->prog->aux->offload; 364 if (offload) { 365 if (!offload->opt_failed && offload->offdev->ops->remove_insns) 366 ret = offload->offdev->ops->remove_insns(env, off, cnt); 367 offload->opt_failed |= ret; 368 } 369 up_read(&bpf_devs_lock); 370 } 371 372 void bpf_prog_dev_bound_destroy(struct bpf_prog *prog) 373 { 374 struct bpf_offload_netdev *ondev; 375 struct net_device *netdev; 376 377 rtnl_lock(); 378 down_write(&bpf_devs_lock); 379 if (prog->aux->offload) { 380 list_del_init(&prog->aux->offload->offloads); 381 382 netdev = prog->aux->offload->netdev; 383 __bpf_prog_offload_destroy(prog); 384 385 ondev = bpf_offload_find_netdev(netdev); 386 if (!ondev->offdev && list_empty(&ondev->progs)) 387 __bpf_offload_dev_netdev_unregister(NULL, netdev); 388 } 389 up_write(&bpf_devs_lock); 390 rtnl_unlock(); 391 } 392 393 static int bpf_prog_offload_translate(struct bpf_prog *prog) 394 { 395 struct bpf_prog_offload *offload; 396 int ret = -ENODEV; 397 398 down_read(&bpf_devs_lock); 399 offload = prog->aux->offload; 400 if (offload) 401 ret = offload->offdev->ops->translate(prog); 402 up_read(&bpf_devs_lock); 403 404 return ret; 405 } 406 407 static unsigned int bpf_prog_warn_on_exec(const void *ctx, 408 const struct bpf_insn *insn) 409 { 410 WARN(1, "attempt to execute device eBPF program on the host!"); 411 return 0; 412 } 413 414 int bpf_prog_offload_compile(struct bpf_prog *prog) 415 { 416 prog->bpf_func = bpf_prog_warn_on_exec; 417 418 return bpf_prog_offload_translate(prog); 419 } 420 421 struct ns_get_path_bpf_prog_args { 422 struct bpf_prog *prog; 423 struct bpf_prog_info *info; 424 }; 425 426 static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data) 427 { 428 struct ns_get_path_bpf_prog_args *args = private_data; 429 struct bpf_prog_aux *aux = args->prog->aux; 430 struct ns_common *ns; 431 struct net *net; 432 433 rtnl_lock(); 434 down_read(&bpf_devs_lock); 435 436 if (aux->offload) { 437 args->info->ifindex = aux->offload->netdev->ifindex; 438 net = dev_net(aux->offload->netdev); 439 get_net(net); 440 ns = &net->ns; 441 } else { 442 args->info->ifindex = 0; 443 ns = NULL; 444 } 445 446 up_read(&bpf_devs_lock); 447 rtnl_unlock(); 448 449 return ns; 450 } 451 452 int bpf_prog_offload_info_fill(struct bpf_prog_info *info, 453 struct bpf_prog *prog) 454 { 455 struct ns_get_path_bpf_prog_args args = { 456 .prog = prog, 457 .info = info, 458 }; 459 struct bpf_prog_aux *aux = prog->aux; 460 struct inode *ns_inode; 461 struct path ns_path; 462 char __user *uinsns; 463 int res; 464 u32 ulen; 465 466 res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args); 467 if (res) { 468 if (!info->ifindex) 469 return -ENODEV; 470 return res; 471 } 472 473 down_read(&bpf_devs_lock); 474 475 if (!aux->offload) { 476 up_read(&bpf_devs_lock); 477 return -ENODEV; 478 } 479 480 ulen = info->jited_prog_len; 481 info->jited_prog_len = aux->offload->jited_len; 482 if (info->jited_prog_len && ulen) { 483 uinsns = u64_to_user_ptr(info->jited_prog_insns); 484 ulen = min_t(u32, info->jited_prog_len, ulen); 485 if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) { 486 up_read(&bpf_devs_lock); 487 return -EFAULT; 488 } 489 } 490 491 up_read(&bpf_devs_lock); 492 493 ns_inode = ns_path.dentry->d_inode; 494 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 495 info->netns_ino = ns_inode->i_ino; 496 path_put(&ns_path); 497 498 return 0; 499 } 500 501 const struct bpf_prog_ops bpf_offload_prog_ops = { 502 }; 503 504 struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr) 505 { 506 struct net *net = current->nsproxy->net_ns; 507 struct bpf_offload_netdev *ondev; 508 struct bpf_offloaded_map *offmap; 509 int err; 510 511 if (!capable(CAP_SYS_ADMIN)) 512 return ERR_PTR(-EPERM); 513 if (attr->map_type != BPF_MAP_TYPE_ARRAY && 514 attr->map_type != BPF_MAP_TYPE_HASH) 515 return ERR_PTR(-EINVAL); 516 517 offmap = bpf_map_area_alloc(sizeof(*offmap), NUMA_NO_NODE); 518 if (!offmap) 519 return ERR_PTR(-ENOMEM); 520 521 bpf_map_init_from_attr(&offmap->map, attr); 522 523 rtnl_lock(); 524 down_write(&bpf_devs_lock); 525 offmap->netdev = __dev_get_by_index(net, attr->map_ifindex); 526 err = bpf_dev_offload_check(offmap->netdev); 527 if (err) 528 goto err_unlock; 529 530 ondev = bpf_offload_find_netdev(offmap->netdev); 531 if (!ondev) { 532 err = -EINVAL; 533 goto err_unlock; 534 } 535 536 err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC); 537 if (err) 538 goto err_unlock; 539 540 list_add_tail(&offmap->offloads, &ondev->maps); 541 up_write(&bpf_devs_lock); 542 rtnl_unlock(); 543 544 return &offmap->map; 545 546 err_unlock: 547 up_write(&bpf_devs_lock); 548 rtnl_unlock(); 549 bpf_map_area_free(offmap); 550 return ERR_PTR(err); 551 } 552 553 void bpf_map_offload_map_free(struct bpf_map *map) 554 { 555 struct bpf_offloaded_map *offmap = map_to_offmap(map); 556 557 rtnl_lock(); 558 down_write(&bpf_devs_lock); 559 if (offmap->netdev) 560 __bpf_map_offload_destroy(offmap); 561 up_write(&bpf_devs_lock); 562 rtnl_unlock(); 563 564 bpf_map_area_free(offmap); 565 } 566 567 u64 bpf_map_offload_map_mem_usage(const struct bpf_map *map) 568 { 569 /* The memory dynamically allocated in netdev dev_ops is not counted */ 570 return sizeof(struct bpf_offloaded_map); 571 } 572 573 int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value) 574 { 575 struct bpf_offloaded_map *offmap = map_to_offmap(map); 576 int ret = -ENODEV; 577 578 down_read(&bpf_devs_lock); 579 if (offmap->netdev) 580 ret = offmap->dev_ops->map_lookup_elem(offmap, key, value); 581 up_read(&bpf_devs_lock); 582 583 return ret; 584 } 585 586 int bpf_map_offload_update_elem(struct bpf_map *map, 587 void *key, void *value, u64 flags) 588 { 589 struct bpf_offloaded_map *offmap = map_to_offmap(map); 590 int ret = -ENODEV; 591 592 if (unlikely(flags > BPF_EXIST)) 593 return -EINVAL; 594 595 down_read(&bpf_devs_lock); 596 if (offmap->netdev) 597 ret = offmap->dev_ops->map_update_elem(offmap, key, value, 598 flags); 599 up_read(&bpf_devs_lock); 600 601 return ret; 602 } 603 604 int bpf_map_offload_delete_elem(struct bpf_map *map, void *key) 605 { 606 struct bpf_offloaded_map *offmap = map_to_offmap(map); 607 int ret = -ENODEV; 608 609 down_read(&bpf_devs_lock); 610 if (offmap->netdev) 611 ret = offmap->dev_ops->map_delete_elem(offmap, key); 612 up_read(&bpf_devs_lock); 613 614 return ret; 615 } 616 617 int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key) 618 { 619 struct bpf_offloaded_map *offmap = map_to_offmap(map); 620 int ret = -ENODEV; 621 622 down_read(&bpf_devs_lock); 623 if (offmap->netdev) 624 ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key); 625 up_read(&bpf_devs_lock); 626 627 return ret; 628 } 629 630 struct ns_get_path_bpf_map_args { 631 struct bpf_offloaded_map *offmap; 632 struct bpf_map_info *info; 633 }; 634 635 static struct ns_common *bpf_map_offload_info_fill_ns(void *private_data) 636 { 637 struct ns_get_path_bpf_map_args *args = private_data; 638 struct ns_common *ns; 639 struct net *net; 640 641 rtnl_lock(); 642 down_read(&bpf_devs_lock); 643 644 if (args->offmap->netdev) { 645 args->info->ifindex = args->offmap->netdev->ifindex; 646 net = dev_net(args->offmap->netdev); 647 get_net(net); 648 ns = &net->ns; 649 } else { 650 args->info->ifindex = 0; 651 ns = NULL; 652 } 653 654 up_read(&bpf_devs_lock); 655 rtnl_unlock(); 656 657 return ns; 658 } 659 660 int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map) 661 { 662 struct ns_get_path_bpf_map_args args = { 663 .offmap = map_to_offmap(map), 664 .info = info, 665 }; 666 struct inode *ns_inode; 667 struct path ns_path; 668 int res; 669 670 res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args); 671 if (res) { 672 if (!info->ifindex) 673 return -ENODEV; 674 return res; 675 } 676 677 ns_inode = ns_path.dentry->d_inode; 678 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 679 info->netns_ino = ns_inode->i_ino; 680 path_put(&ns_path); 681 682 return 0; 683 } 684 685 static bool __bpf_offload_dev_match(struct bpf_prog *prog, 686 struct net_device *netdev) 687 { 688 struct bpf_offload_netdev *ondev1, *ondev2; 689 struct bpf_prog_offload *offload; 690 691 if (!bpf_prog_is_dev_bound(prog->aux)) 692 return false; 693 694 offload = prog->aux->offload; 695 if (!offload) 696 return false; 697 if (offload->netdev == netdev) 698 return true; 699 700 ondev1 = bpf_offload_find_netdev(offload->netdev); 701 ondev2 = bpf_offload_find_netdev(netdev); 702 703 return ondev1 && ondev2 && ondev1->offdev == ondev2->offdev; 704 } 705 706 bool bpf_offload_dev_match(struct bpf_prog *prog, struct net_device *netdev) 707 { 708 bool ret; 709 710 down_read(&bpf_devs_lock); 711 ret = __bpf_offload_dev_match(prog, netdev); 712 up_read(&bpf_devs_lock); 713 714 return ret; 715 } 716 EXPORT_SYMBOL_GPL(bpf_offload_dev_match); 717 718 bool bpf_prog_dev_bound_match(const struct bpf_prog *lhs, const struct bpf_prog *rhs) 719 { 720 bool ret; 721 722 if (bpf_prog_is_offloaded(lhs->aux) != bpf_prog_is_offloaded(rhs->aux)) 723 return false; 724 725 down_read(&bpf_devs_lock); 726 ret = lhs->aux->offload && rhs->aux->offload && 727 lhs->aux->offload->netdev && 728 lhs->aux->offload->netdev == rhs->aux->offload->netdev; 729 up_read(&bpf_devs_lock); 730 731 return ret; 732 } 733 734 bool bpf_offload_prog_map_match(struct bpf_prog *prog, struct bpf_map *map) 735 { 736 struct bpf_offloaded_map *offmap; 737 bool ret; 738 739 if (!bpf_map_is_offloaded(map)) 740 return bpf_map_offload_neutral(map); 741 offmap = map_to_offmap(map); 742 743 down_read(&bpf_devs_lock); 744 ret = __bpf_offload_dev_match(prog, offmap->netdev); 745 up_read(&bpf_devs_lock); 746 747 return ret; 748 } 749 750 int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev, 751 struct net_device *netdev) 752 { 753 int err; 754 755 down_write(&bpf_devs_lock); 756 err = __bpf_offload_dev_netdev_register(offdev, netdev); 757 up_write(&bpf_devs_lock); 758 return err; 759 } 760 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_register); 761 762 void bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev, 763 struct net_device *netdev) 764 { 765 down_write(&bpf_devs_lock); 766 __bpf_offload_dev_netdev_unregister(offdev, netdev); 767 up_write(&bpf_devs_lock); 768 } 769 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_unregister); 770 771 struct bpf_offload_dev * 772 bpf_offload_dev_create(const struct bpf_prog_offload_ops *ops, void *priv) 773 { 774 struct bpf_offload_dev *offdev; 775 776 offdev = kzalloc(sizeof(*offdev), GFP_KERNEL); 777 if (!offdev) 778 return ERR_PTR(-ENOMEM); 779 780 offdev->ops = ops; 781 offdev->priv = priv; 782 INIT_LIST_HEAD(&offdev->netdevs); 783 784 return offdev; 785 } 786 EXPORT_SYMBOL_GPL(bpf_offload_dev_create); 787 788 void bpf_offload_dev_destroy(struct bpf_offload_dev *offdev) 789 { 790 WARN_ON(!list_empty(&offdev->netdevs)); 791 kfree(offdev); 792 } 793 EXPORT_SYMBOL_GPL(bpf_offload_dev_destroy); 794 795 void *bpf_offload_dev_priv(struct bpf_offload_dev *offdev) 796 { 797 return offdev->priv; 798 } 799 EXPORT_SYMBOL_GPL(bpf_offload_dev_priv); 800 801 void bpf_dev_bound_netdev_unregister(struct net_device *dev) 802 { 803 struct bpf_offload_netdev *ondev; 804 805 ASSERT_RTNL(); 806 807 down_write(&bpf_devs_lock); 808 ondev = bpf_offload_find_netdev(dev); 809 if (ondev && !ondev->offdev) 810 __bpf_offload_dev_netdev_unregister(NULL, ondev->netdev); 811 up_write(&bpf_devs_lock); 812 } 813 814 int bpf_dev_bound_kfunc_check(struct bpf_verifier_log *log, 815 struct bpf_prog_aux *prog_aux) 816 { 817 if (!bpf_prog_is_dev_bound(prog_aux)) { 818 bpf_log(log, "metadata kfuncs require device-bound program\n"); 819 return -EINVAL; 820 } 821 822 if (bpf_prog_is_offloaded(prog_aux)) { 823 bpf_log(log, "metadata kfuncs can't be offloaded\n"); 824 return -EINVAL; 825 } 826 827 return 0; 828 } 829 830 void *bpf_dev_bound_resolve_kfunc(struct bpf_prog *prog, u32 func_id) 831 { 832 const struct xdp_metadata_ops *ops; 833 void *p = NULL; 834 835 /* We don't hold bpf_devs_lock while resolving several 836 * kfuncs and can race with the unregister_netdevice(). 837 * We rely on bpf_dev_bound_match() check at attach 838 * to render this program unusable. 839 */ 840 down_read(&bpf_devs_lock); 841 if (!prog->aux->offload) 842 goto out; 843 844 ops = prog->aux->offload->netdev->xdp_metadata_ops; 845 if (!ops) 846 goto out; 847 848 if (func_id == bpf_xdp_metadata_kfunc_id(XDP_METADATA_KFUNC_RX_TIMESTAMP)) 849 p = ops->xmo_rx_timestamp; 850 else if (func_id == bpf_xdp_metadata_kfunc_id(XDP_METADATA_KFUNC_RX_HASH)) 851 p = ops->xmo_rx_hash; 852 out: 853 up_read(&bpf_devs_lock); 854 855 return p; 856 } 857 858 static int __init bpf_offload_init(void) 859 { 860 return rhashtable_init(&offdevs, &offdevs_params); 861 } 862 863 core_initcall(bpf_offload_init); 864