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 | BPF_F_XDP_HAS_FRAGS)) 236 return -EINVAL; 237 238 /* Frags are allowed only if program is dev-bound-only, but not 239 * if it is requesting bpf offload. 240 */ 241 if (attr->prog_flags & BPF_F_XDP_HAS_FRAGS && 242 !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY)) 243 return -EINVAL; 244 245 if (attr->prog_type == BPF_PROG_TYPE_SCHED_CLS && 246 attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY) 247 return -EINVAL; 248 249 netdev = dev_get_by_index(current->nsproxy->net_ns, attr->prog_ifindex); 250 if (!netdev) 251 return -EINVAL; 252 253 err = bpf_dev_offload_check(netdev); 254 if (err) 255 goto out; 256 257 prog->aux->offload_requested = !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY); 258 259 down_write(&bpf_devs_lock); 260 err = __bpf_prog_dev_bound_init(prog, netdev); 261 up_write(&bpf_devs_lock); 262 263 out: 264 dev_put(netdev); 265 return err; 266 } 267 268 int bpf_prog_dev_bound_inherit(struct bpf_prog *new_prog, struct bpf_prog *old_prog) 269 { 270 int err; 271 272 if (!bpf_prog_is_dev_bound(old_prog->aux)) 273 return 0; 274 275 if (bpf_prog_is_offloaded(old_prog->aux)) 276 return -EINVAL; 277 278 new_prog->aux->dev_bound = old_prog->aux->dev_bound; 279 new_prog->aux->offload_requested = old_prog->aux->offload_requested; 280 281 down_write(&bpf_devs_lock); 282 if (!old_prog->aux->offload) { 283 err = -EINVAL; 284 goto out; 285 } 286 287 err = __bpf_prog_dev_bound_init(new_prog, old_prog->aux->offload->netdev); 288 289 out: 290 up_write(&bpf_devs_lock); 291 return err; 292 } 293 294 int bpf_prog_offload_verifier_prep(struct bpf_prog *prog) 295 { 296 struct bpf_prog_offload *offload; 297 int ret = -ENODEV; 298 299 down_read(&bpf_devs_lock); 300 offload = prog->aux->offload; 301 if (offload) { 302 ret = offload->offdev->ops->prepare(prog); 303 offload->dev_state = !ret; 304 } 305 up_read(&bpf_devs_lock); 306 307 return ret; 308 } 309 310 int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env, 311 int insn_idx, int prev_insn_idx) 312 { 313 struct bpf_prog_offload *offload; 314 int ret = -ENODEV; 315 316 down_read(&bpf_devs_lock); 317 offload = env->prog->aux->offload; 318 if (offload) 319 ret = offload->offdev->ops->insn_hook(env, insn_idx, 320 prev_insn_idx); 321 up_read(&bpf_devs_lock); 322 323 return ret; 324 } 325 326 int bpf_prog_offload_finalize(struct bpf_verifier_env *env) 327 { 328 struct bpf_prog_offload *offload; 329 int ret = -ENODEV; 330 331 down_read(&bpf_devs_lock); 332 offload = env->prog->aux->offload; 333 if (offload) { 334 if (offload->offdev->ops->finalize) 335 ret = offload->offdev->ops->finalize(env); 336 else 337 ret = 0; 338 } 339 up_read(&bpf_devs_lock); 340 341 return ret; 342 } 343 344 void 345 bpf_prog_offload_replace_insn(struct bpf_verifier_env *env, u32 off, 346 struct bpf_insn *insn) 347 { 348 const struct bpf_prog_offload_ops *ops; 349 struct bpf_prog_offload *offload; 350 int ret = -EOPNOTSUPP; 351 352 down_read(&bpf_devs_lock); 353 offload = env->prog->aux->offload; 354 if (offload) { 355 ops = offload->offdev->ops; 356 if (!offload->opt_failed && ops->replace_insn) 357 ret = ops->replace_insn(env, off, insn); 358 offload->opt_failed |= ret; 359 } 360 up_read(&bpf_devs_lock); 361 } 362 363 void 364 bpf_prog_offload_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt) 365 { 366 struct bpf_prog_offload *offload; 367 int ret = -EOPNOTSUPP; 368 369 down_read(&bpf_devs_lock); 370 offload = env->prog->aux->offload; 371 if (offload) { 372 if (!offload->opt_failed && offload->offdev->ops->remove_insns) 373 ret = offload->offdev->ops->remove_insns(env, off, cnt); 374 offload->opt_failed |= ret; 375 } 376 up_read(&bpf_devs_lock); 377 } 378 379 void bpf_prog_dev_bound_destroy(struct bpf_prog *prog) 380 { 381 struct bpf_offload_netdev *ondev; 382 struct net_device *netdev; 383 384 rtnl_lock(); 385 down_write(&bpf_devs_lock); 386 if (prog->aux->offload) { 387 list_del_init(&prog->aux->offload->offloads); 388 389 netdev = prog->aux->offload->netdev; 390 __bpf_prog_offload_destroy(prog); 391 392 ondev = bpf_offload_find_netdev(netdev); 393 if (!ondev->offdev && list_empty(&ondev->progs)) 394 __bpf_offload_dev_netdev_unregister(NULL, netdev); 395 } 396 up_write(&bpf_devs_lock); 397 rtnl_unlock(); 398 } 399 400 static int bpf_prog_offload_translate(struct bpf_prog *prog) 401 { 402 struct bpf_prog_offload *offload; 403 int ret = -ENODEV; 404 405 down_read(&bpf_devs_lock); 406 offload = prog->aux->offload; 407 if (offload) 408 ret = offload->offdev->ops->translate(prog); 409 up_read(&bpf_devs_lock); 410 411 return ret; 412 } 413 414 static unsigned int bpf_prog_warn_on_exec(const void *ctx, 415 const struct bpf_insn *insn) 416 { 417 WARN(1, "attempt to execute device eBPF program on the host!"); 418 return 0; 419 } 420 421 int bpf_prog_offload_compile(struct bpf_prog *prog) 422 { 423 prog->bpf_func = bpf_prog_warn_on_exec; 424 425 return bpf_prog_offload_translate(prog); 426 } 427 428 struct ns_get_path_bpf_prog_args { 429 struct bpf_prog *prog; 430 struct bpf_prog_info *info; 431 }; 432 433 static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data) 434 { 435 struct ns_get_path_bpf_prog_args *args = private_data; 436 struct bpf_prog_aux *aux = args->prog->aux; 437 struct ns_common *ns; 438 struct net *net; 439 440 rtnl_lock(); 441 down_read(&bpf_devs_lock); 442 443 if (aux->offload) { 444 args->info->ifindex = aux->offload->netdev->ifindex; 445 net = dev_net(aux->offload->netdev); 446 get_net(net); 447 ns = &net->ns; 448 } else { 449 args->info->ifindex = 0; 450 ns = NULL; 451 } 452 453 up_read(&bpf_devs_lock); 454 rtnl_unlock(); 455 456 return ns; 457 } 458 459 int bpf_prog_offload_info_fill(struct bpf_prog_info *info, 460 struct bpf_prog *prog) 461 { 462 struct ns_get_path_bpf_prog_args args = { 463 .prog = prog, 464 .info = info, 465 }; 466 struct bpf_prog_aux *aux = prog->aux; 467 struct inode *ns_inode; 468 struct path ns_path; 469 char __user *uinsns; 470 int res; 471 u32 ulen; 472 473 res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args); 474 if (res) { 475 if (!info->ifindex) 476 return -ENODEV; 477 return res; 478 } 479 480 down_read(&bpf_devs_lock); 481 482 if (!aux->offload) { 483 up_read(&bpf_devs_lock); 484 return -ENODEV; 485 } 486 487 ulen = info->jited_prog_len; 488 info->jited_prog_len = aux->offload->jited_len; 489 if (info->jited_prog_len && ulen) { 490 uinsns = u64_to_user_ptr(info->jited_prog_insns); 491 ulen = min_t(u32, info->jited_prog_len, ulen); 492 if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) { 493 up_read(&bpf_devs_lock); 494 return -EFAULT; 495 } 496 } 497 498 up_read(&bpf_devs_lock); 499 500 ns_inode = ns_path.dentry->d_inode; 501 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 502 info->netns_ino = ns_inode->i_ino; 503 path_put(&ns_path); 504 505 return 0; 506 } 507 508 const struct bpf_prog_ops bpf_offload_prog_ops = { 509 }; 510 511 struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr) 512 { 513 struct net *net = current->nsproxy->net_ns; 514 struct bpf_offload_netdev *ondev; 515 struct bpf_offloaded_map *offmap; 516 int err; 517 518 if (!capable(CAP_SYS_ADMIN)) 519 return ERR_PTR(-EPERM); 520 if (attr->map_type != BPF_MAP_TYPE_ARRAY && 521 attr->map_type != BPF_MAP_TYPE_HASH) 522 return ERR_PTR(-EINVAL); 523 524 offmap = bpf_map_area_alloc(sizeof(*offmap), NUMA_NO_NODE); 525 if (!offmap) 526 return ERR_PTR(-ENOMEM); 527 528 bpf_map_init_from_attr(&offmap->map, attr); 529 530 rtnl_lock(); 531 down_write(&bpf_devs_lock); 532 offmap->netdev = __dev_get_by_index(net, attr->map_ifindex); 533 err = bpf_dev_offload_check(offmap->netdev); 534 if (err) 535 goto err_unlock; 536 537 ondev = bpf_offload_find_netdev(offmap->netdev); 538 if (!ondev) { 539 err = -EINVAL; 540 goto err_unlock; 541 } 542 543 err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC); 544 if (err) 545 goto err_unlock; 546 547 list_add_tail(&offmap->offloads, &ondev->maps); 548 up_write(&bpf_devs_lock); 549 rtnl_unlock(); 550 551 return &offmap->map; 552 553 err_unlock: 554 up_write(&bpf_devs_lock); 555 rtnl_unlock(); 556 bpf_map_area_free(offmap); 557 return ERR_PTR(err); 558 } 559 560 void bpf_map_offload_map_free(struct bpf_map *map) 561 { 562 struct bpf_offloaded_map *offmap = map_to_offmap(map); 563 564 rtnl_lock(); 565 down_write(&bpf_devs_lock); 566 if (offmap->netdev) 567 __bpf_map_offload_destroy(offmap); 568 up_write(&bpf_devs_lock); 569 rtnl_unlock(); 570 571 bpf_map_area_free(offmap); 572 } 573 574 u64 bpf_map_offload_map_mem_usage(const struct bpf_map *map) 575 { 576 /* The memory dynamically allocated in netdev dev_ops is not counted */ 577 return sizeof(struct bpf_offloaded_map); 578 } 579 580 int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value) 581 { 582 struct bpf_offloaded_map *offmap = map_to_offmap(map); 583 int ret = -ENODEV; 584 585 down_read(&bpf_devs_lock); 586 if (offmap->netdev) 587 ret = offmap->dev_ops->map_lookup_elem(offmap, key, value); 588 up_read(&bpf_devs_lock); 589 590 return ret; 591 } 592 593 int bpf_map_offload_update_elem(struct bpf_map *map, 594 void *key, void *value, u64 flags) 595 { 596 struct bpf_offloaded_map *offmap = map_to_offmap(map); 597 int ret = -ENODEV; 598 599 if (unlikely(flags > BPF_EXIST)) 600 return -EINVAL; 601 602 down_read(&bpf_devs_lock); 603 if (offmap->netdev) 604 ret = offmap->dev_ops->map_update_elem(offmap, key, value, 605 flags); 606 up_read(&bpf_devs_lock); 607 608 return ret; 609 } 610 611 int bpf_map_offload_delete_elem(struct bpf_map *map, void *key) 612 { 613 struct bpf_offloaded_map *offmap = map_to_offmap(map); 614 int ret = -ENODEV; 615 616 down_read(&bpf_devs_lock); 617 if (offmap->netdev) 618 ret = offmap->dev_ops->map_delete_elem(offmap, key); 619 up_read(&bpf_devs_lock); 620 621 return ret; 622 } 623 624 int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key) 625 { 626 struct bpf_offloaded_map *offmap = map_to_offmap(map); 627 int ret = -ENODEV; 628 629 down_read(&bpf_devs_lock); 630 if (offmap->netdev) 631 ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key); 632 up_read(&bpf_devs_lock); 633 634 return ret; 635 } 636 637 struct ns_get_path_bpf_map_args { 638 struct bpf_offloaded_map *offmap; 639 struct bpf_map_info *info; 640 }; 641 642 static struct ns_common *bpf_map_offload_info_fill_ns(void *private_data) 643 { 644 struct ns_get_path_bpf_map_args *args = private_data; 645 struct ns_common *ns; 646 struct net *net; 647 648 rtnl_lock(); 649 down_read(&bpf_devs_lock); 650 651 if (args->offmap->netdev) { 652 args->info->ifindex = args->offmap->netdev->ifindex; 653 net = dev_net(args->offmap->netdev); 654 get_net(net); 655 ns = &net->ns; 656 } else { 657 args->info->ifindex = 0; 658 ns = NULL; 659 } 660 661 up_read(&bpf_devs_lock); 662 rtnl_unlock(); 663 664 return ns; 665 } 666 667 int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map) 668 { 669 struct ns_get_path_bpf_map_args args = { 670 .offmap = map_to_offmap(map), 671 .info = info, 672 }; 673 struct inode *ns_inode; 674 struct path ns_path; 675 int res; 676 677 res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args); 678 if (res) { 679 if (!info->ifindex) 680 return -ENODEV; 681 return res; 682 } 683 684 ns_inode = ns_path.dentry->d_inode; 685 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 686 info->netns_ino = ns_inode->i_ino; 687 path_put(&ns_path); 688 689 return 0; 690 } 691 692 static bool __bpf_offload_dev_match(struct bpf_prog *prog, 693 struct net_device *netdev) 694 { 695 struct bpf_offload_netdev *ondev1, *ondev2; 696 struct bpf_prog_offload *offload; 697 698 if (!bpf_prog_is_dev_bound(prog->aux)) 699 return false; 700 701 offload = prog->aux->offload; 702 if (!offload) 703 return false; 704 if (offload->netdev == netdev) 705 return true; 706 707 ondev1 = bpf_offload_find_netdev(offload->netdev); 708 ondev2 = bpf_offload_find_netdev(netdev); 709 710 return ondev1 && ondev2 && ondev1->offdev == ondev2->offdev; 711 } 712 713 bool bpf_offload_dev_match(struct bpf_prog *prog, struct net_device *netdev) 714 { 715 bool ret; 716 717 down_read(&bpf_devs_lock); 718 ret = __bpf_offload_dev_match(prog, netdev); 719 up_read(&bpf_devs_lock); 720 721 return ret; 722 } 723 EXPORT_SYMBOL_GPL(bpf_offload_dev_match); 724 725 bool bpf_prog_dev_bound_match(const struct bpf_prog *lhs, const struct bpf_prog *rhs) 726 { 727 bool ret; 728 729 if (bpf_prog_is_offloaded(lhs->aux) != bpf_prog_is_offloaded(rhs->aux)) 730 return false; 731 732 down_read(&bpf_devs_lock); 733 ret = lhs->aux->offload && rhs->aux->offload && 734 lhs->aux->offload->netdev && 735 lhs->aux->offload->netdev == rhs->aux->offload->netdev; 736 up_read(&bpf_devs_lock); 737 738 return ret; 739 } 740 741 bool bpf_offload_prog_map_match(struct bpf_prog *prog, struct bpf_map *map) 742 { 743 struct bpf_offloaded_map *offmap; 744 bool ret; 745 746 if (!bpf_map_is_offloaded(map)) 747 return bpf_map_offload_neutral(map); 748 offmap = map_to_offmap(map); 749 750 down_read(&bpf_devs_lock); 751 ret = __bpf_offload_dev_match(prog, offmap->netdev); 752 up_read(&bpf_devs_lock); 753 754 return ret; 755 } 756 757 int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev, 758 struct net_device *netdev) 759 { 760 int err; 761 762 down_write(&bpf_devs_lock); 763 err = __bpf_offload_dev_netdev_register(offdev, netdev); 764 up_write(&bpf_devs_lock); 765 return err; 766 } 767 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_register); 768 769 void bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev, 770 struct net_device *netdev) 771 { 772 down_write(&bpf_devs_lock); 773 __bpf_offload_dev_netdev_unregister(offdev, netdev); 774 up_write(&bpf_devs_lock); 775 } 776 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_unregister); 777 778 struct bpf_offload_dev * 779 bpf_offload_dev_create(const struct bpf_prog_offload_ops *ops, void *priv) 780 { 781 struct bpf_offload_dev *offdev; 782 783 offdev = kzalloc(sizeof(*offdev), GFP_KERNEL); 784 if (!offdev) 785 return ERR_PTR(-ENOMEM); 786 787 offdev->ops = ops; 788 offdev->priv = priv; 789 INIT_LIST_HEAD(&offdev->netdevs); 790 791 return offdev; 792 } 793 EXPORT_SYMBOL_GPL(bpf_offload_dev_create); 794 795 void bpf_offload_dev_destroy(struct bpf_offload_dev *offdev) 796 { 797 WARN_ON(!list_empty(&offdev->netdevs)); 798 kfree(offdev); 799 } 800 EXPORT_SYMBOL_GPL(bpf_offload_dev_destroy); 801 802 void *bpf_offload_dev_priv(struct bpf_offload_dev *offdev) 803 { 804 return offdev->priv; 805 } 806 EXPORT_SYMBOL_GPL(bpf_offload_dev_priv); 807 808 void bpf_dev_bound_netdev_unregister(struct net_device *dev) 809 { 810 struct bpf_offload_netdev *ondev; 811 812 ASSERT_RTNL(); 813 814 down_write(&bpf_devs_lock); 815 ondev = bpf_offload_find_netdev(dev); 816 if (ondev && !ondev->offdev) 817 __bpf_offload_dev_netdev_unregister(NULL, ondev->netdev); 818 up_write(&bpf_devs_lock); 819 } 820 821 int bpf_dev_bound_kfunc_check(struct bpf_verifier_log *log, 822 struct bpf_prog_aux *prog_aux) 823 { 824 if (!bpf_prog_is_dev_bound(prog_aux)) { 825 bpf_log(log, "metadata kfuncs require device-bound program\n"); 826 return -EINVAL; 827 } 828 829 if (bpf_prog_is_offloaded(prog_aux)) { 830 bpf_log(log, "metadata kfuncs can't be offloaded\n"); 831 return -EINVAL; 832 } 833 834 return 0; 835 } 836 837 void *bpf_dev_bound_resolve_kfunc(struct bpf_prog *prog, u32 func_id) 838 { 839 const struct xdp_metadata_ops *ops; 840 void *p = NULL; 841 842 /* We don't hold bpf_devs_lock while resolving several 843 * kfuncs and can race with the unregister_netdevice(). 844 * We rely on bpf_dev_bound_match() check at attach 845 * to render this program unusable. 846 */ 847 down_read(&bpf_devs_lock); 848 if (!prog->aux->offload) 849 goto out; 850 851 ops = prog->aux->offload->netdev->xdp_metadata_ops; 852 if (!ops) 853 goto out; 854 855 #define XDP_METADATA_KFUNC(name, _, __, xmo) \ 856 if (func_id == bpf_xdp_metadata_kfunc_id(name)) p = ops->xmo; 857 XDP_METADATA_KFUNC_xxx 858 #undef XDP_METADATA_KFUNC 859 860 out: 861 up_read(&bpf_devs_lock); 862 863 return p; 864 } 865 866 static int __init bpf_offload_init(void) 867 { 868 return rhashtable_init(&offdevs, &offdevs_params); 869 } 870 871 core_initcall(bpf_offload_init); 872