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 /* When program is offloaded require presence of "true" 203 * bpf_offload_netdev, avoid the one created for !ondev case below. 204 */ 205 if (bpf_prog_is_offloaded(prog->aux) && (!ondev || !ondev->offdev)) { 206 err = -EINVAL; 207 goto err_free; 208 } 209 if (!ondev) { 210 /* When only binding to the device, explicitly 211 * create an entry in the hashtable. 212 */ 213 err = __bpf_offload_dev_netdev_register(NULL, offload->netdev); 214 if (err) 215 goto err_free; 216 ondev = bpf_offload_find_netdev(offload->netdev); 217 } 218 offload->offdev = ondev->offdev; 219 prog->aux->offload = offload; 220 list_add_tail(&offload->offloads, &ondev->progs); 221 222 return 0; 223 err_free: 224 kfree(offload); 225 return err; 226 } 227 228 int bpf_prog_dev_bound_init(struct bpf_prog *prog, union bpf_attr *attr) 229 { 230 struct net_device *netdev; 231 int err; 232 233 if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS && 234 attr->prog_type != BPF_PROG_TYPE_XDP) 235 return -EINVAL; 236 237 if (attr->prog_flags & ~BPF_F_XDP_DEV_BOUND_ONLY) 238 return -EINVAL; 239 240 if (attr->prog_type == BPF_PROG_TYPE_SCHED_CLS && 241 attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY) 242 return -EINVAL; 243 244 netdev = dev_get_by_index(current->nsproxy->net_ns, attr->prog_ifindex); 245 if (!netdev) 246 return -EINVAL; 247 248 err = bpf_dev_offload_check(netdev); 249 if (err) 250 goto out; 251 252 prog->aux->offload_requested = !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY); 253 254 down_write(&bpf_devs_lock); 255 err = __bpf_prog_dev_bound_init(prog, netdev); 256 up_write(&bpf_devs_lock); 257 258 out: 259 dev_put(netdev); 260 return err; 261 } 262 263 int bpf_prog_dev_bound_inherit(struct bpf_prog *new_prog, struct bpf_prog *old_prog) 264 { 265 int err; 266 267 if (!bpf_prog_is_dev_bound(old_prog->aux)) 268 return 0; 269 270 if (bpf_prog_is_offloaded(old_prog->aux)) 271 return -EINVAL; 272 273 new_prog->aux->dev_bound = old_prog->aux->dev_bound; 274 new_prog->aux->offload_requested = old_prog->aux->offload_requested; 275 276 down_write(&bpf_devs_lock); 277 if (!old_prog->aux->offload) { 278 err = -EINVAL; 279 goto out; 280 } 281 282 err = __bpf_prog_dev_bound_init(new_prog, old_prog->aux->offload->netdev); 283 284 out: 285 up_write(&bpf_devs_lock); 286 return err; 287 } 288 289 int bpf_prog_offload_verifier_prep(struct bpf_prog *prog) 290 { 291 struct bpf_prog_offload *offload; 292 int ret = -ENODEV; 293 294 down_read(&bpf_devs_lock); 295 offload = prog->aux->offload; 296 if (offload) { 297 ret = offload->offdev->ops->prepare(prog); 298 offload->dev_state = !ret; 299 } 300 up_read(&bpf_devs_lock); 301 302 return ret; 303 } 304 305 int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env, 306 int insn_idx, int prev_insn_idx) 307 { 308 struct bpf_prog_offload *offload; 309 int ret = -ENODEV; 310 311 down_read(&bpf_devs_lock); 312 offload = env->prog->aux->offload; 313 if (offload) 314 ret = offload->offdev->ops->insn_hook(env, insn_idx, 315 prev_insn_idx); 316 up_read(&bpf_devs_lock); 317 318 return ret; 319 } 320 321 int bpf_prog_offload_finalize(struct bpf_verifier_env *env) 322 { 323 struct bpf_prog_offload *offload; 324 int ret = -ENODEV; 325 326 down_read(&bpf_devs_lock); 327 offload = env->prog->aux->offload; 328 if (offload) { 329 if (offload->offdev->ops->finalize) 330 ret = offload->offdev->ops->finalize(env); 331 else 332 ret = 0; 333 } 334 up_read(&bpf_devs_lock); 335 336 return ret; 337 } 338 339 void 340 bpf_prog_offload_replace_insn(struct bpf_verifier_env *env, u32 off, 341 struct bpf_insn *insn) 342 { 343 const struct bpf_prog_offload_ops *ops; 344 struct bpf_prog_offload *offload; 345 int ret = -EOPNOTSUPP; 346 347 down_read(&bpf_devs_lock); 348 offload = env->prog->aux->offload; 349 if (offload) { 350 ops = offload->offdev->ops; 351 if (!offload->opt_failed && ops->replace_insn) 352 ret = ops->replace_insn(env, off, insn); 353 offload->opt_failed |= ret; 354 } 355 up_read(&bpf_devs_lock); 356 } 357 358 void 359 bpf_prog_offload_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt) 360 { 361 struct bpf_prog_offload *offload; 362 int ret = -EOPNOTSUPP; 363 364 down_read(&bpf_devs_lock); 365 offload = env->prog->aux->offload; 366 if (offload) { 367 if (!offload->opt_failed && offload->offdev->ops->remove_insns) 368 ret = offload->offdev->ops->remove_insns(env, off, cnt); 369 offload->opt_failed |= ret; 370 } 371 up_read(&bpf_devs_lock); 372 } 373 374 void bpf_prog_dev_bound_destroy(struct bpf_prog *prog) 375 { 376 struct bpf_offload_netdev *ondev; 377 struct net_device *netdev; 378 379 rtnl_lock(); 380 down_write(&bpf_devs_lock); 381 if (prog->aux->offload) { 382 list_del_init(&prog->aux->offload->offloads); 383 384 netdev = prog->aux->offload->netdev; 385 __bpf_prog_offload_destroy(prog); 386 387 ondev = bpf_offload_find_netdev(netdev); 388 if (!ondev->offdev && list_empty(&ondev->progs)) 389 __bpf_offload_dev_netdev_unregister(NULL, netdev); 390 } 391 up_write(&bpf_devs_lock); 392 rtnl_unlock(); 393 } 394 395 static int bpf_prog_offload_translate(struct bpf_prog *prog) 396 { 397 struct bpf_prog_offload *offload; 398 int ret = -ENODEV; 399 400 down_read(&bpf_devs_lock); 401 offload = prog->aux->offload; 402 if (offload) 403 ret = offload->offdev->ops->translate(prog); 404 up_read(&bpf_devs_lock); 405 406 return ret; 407 } 408 409 static unsigned int bpf_prog_warn_on_exec(const void *ctx, 410 const struct bpf_insn *insn) 411 { 412 WARN(1, "attempt to execute device eBPF program on the host!"); 413 return 0; 414 } 415 416 int bpf_prog_offload_compile(struct bpf_prog *prog) 417 { 418 prog->bpf_func = bpf_prog_warn_on_exec; 419 420 return bpf_prog_offload_translate(prog); 421 } 422 423 struct ns_get_path_bpf_prog_args { 424 struct bpf_prog *prog; 425 struct bpf_prog_info *info; 426 }; 427 428 static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data) 429 { 430 struct ns_get_path_bpf_prog_args *args = private_data; 431 struct bpf_prog_aux *aux = args->prog->aux; 432 struct ns_common *ns; 433 struct net *net; 434 435 rtnl_lock(); 436 down_read(&bpf_devs_lock); 437 438 if (aux->offload) { 439 args->info->ifindex = aux->offload->netdev->ifindex; 440 net = dev_net(aux->offload->netdev); 441 get_net(net); 442 ns = &net->ns; 443 } else { 444 args->info->ifindex = 0; 445 ns = NULL; 446 } 447 448 up_read(&bpf_devs_lock); 449 rtnl_unlock(); 450 451 return ns; 452 } 453 454 int bpf_prog_offload_info_fill(struct bpf_prog_info *info, 455 struct bpf_prog *prog) 456 { 457 struct ns_get_path_bpf_prog_args args = { 458 .prog = prog, 459 .info = info, 460 }; 461 struct bpf_prog_aux *aux = prog->aux; 462 struct inode *ns_inode; 463 struct path ns_path; 464 char __user *uinsns; 465 int res; 466 u32 ulen; 467 468 res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args); 469 if (res) { 470 if (!info->ifindex) 471 return -ENODEV; 472 return res; 473 } 474 475 down_read(&bpf_devs_lock); 476 477 if (!aux->offload) { 478 up_read(&bpf_devs_lock); 479 return -ENODEV; 480 } 481 482 ulen = info->jited_prog_len; 483 info->jited_prog_len = aux->offload->jited_len; 484 if (info->jited_prog_len && ulen) { 485 uinsns = u64_to_user_ptr(info->jited_prog_insns); 486 ulen = min_t(u32, info->jited_prog_len, ulen); 487 if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) { 488 up_read(&bpf_devs_lock); 489 return -EFAULT; 490 } 491 } 492 493 up_read(&bpf_devs_lock); 494 495 ns_inode = ns_path.dentry->d_inode; 496 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 497 info->netns_ino = ns_inode->i_ino; 498 path_put(&ns_path); 499 500 return 0; 501 } 502 503 const struct bpf_prog_ops bpf_offload_prog_ops = { 504 }; 505 506 struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr) 507 { 508 struct net *net = current->nsproxy->net_ns; 509 struct bpf_offload_netdev *ondev; 510 struct bpf_offloaded_map *offmap; 511 int err; 512 513 if (!capable(CAP_SYS_ADMIN)) 514 return ERR_PTR(-EPERM); 515 if (attr->map_type != BPF_MAP_TYPE_ARRAY && 516 attr->map_type != BPF_MAP_TYPE_HASH) 517 return ERR_PTR(-EINVAL); 518 519 offmap = bpf_map_area_alloc(sizeof(*offmap), NUMA_NO_NODE); 520 if (!offmap) 521 return ERR_PTR(-ENOMEM); 522 523 bpf_map_init_from_attr(&offmap->map, attr); 524 525 rtnl_lock(); 526 down_write(&bpf_devs_lock); 527 offmap->netdev = __dev_get_by_index(net, attr->map_ifindex); 528 err = bpf_dev_offload_check(offmap->netdev); 529 if (err) 530 goto err_unlock; 531 532 ondev = bpf_offload_find_netdev(offmap->netdev); 533 if (!ondev) { 534 err = -EINVAL; 535 goto err_unlock; 536 } 537 538 err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC); 539 if (err) 540 goto err_unlock; 541 542 list_add_tail(&offmap->offloads, &ondev->maps); 543 up_write(&bpf_devs_lock); 544 rtnl_unlock(); 545 546 return &offmap->map; 547 548 err_unlock: 549 up_write(&bpf_devs_lock); 550 rtnl_unlock(); 551 bpf_map_area_free(offmap); 552 return ERR_PTR(err); 553 } 554 555 void bpf_map_offload_map_free(struct bpf_map *map) 556 { 557 struct bpf_offloaded_map *offmap = map_to_offmap(map); 558 559 rtnl_lock(); 560 down_write(&bpf_devs_lock); 561 if (offmap->netdev) 562 __bpf_map_offload_destroy(offmap); 563 up_write(&bpf_devs_lock); 564 rtnl_unlock(); 565 566 bpf_map_area_free(offmap); 567 } 568 569 u64 bpf_map_offload_map_mem_usage(const struct bpf_map *map) 570 { 571 /* The memory dynamically allocated in netdev dev_ops is not counted */ 572 return sizeof(struct bpf_offloaded_map); 573 } 574 575 int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value) 576 { 577 struct bpf_offloaded_map *offmap = map_to_offmap(map); 578 int ret = -ENODEV; 579 580 down_read(&bpf_devs_lock); 581 if (offmap->netdev) 582 ret = offmap->dev_ops->map_lookup_elem(offmap, key, value); 583 up_read(&bpf_devs_lock); 584 585 return ret; 586 } 587 588 int bpf_map_offload_update_elem(struct bpf_map *map, 589 void *key, void *value, u64 flags) 590 { 591 struct bpf_offloaded_map *offmap = map_to_offmap(map); 592 int ret = -ENODEV; 593 594 if (unlikely(flags > BPF_EXIST)) 595 return -EINVAL; 596 597 down_read(&bpf_devs_lock); 598 if (offmap->netdev) 599 ret = offmap->dev_ops->map_update_elem(offmap, key, value, 600 flags); 601 up_read(&bpf_devs_lock); 602 603 return ret; 604 } 605 606 int bpf_map_offload_delete_elem(struct bpf_map *map, void *key) 607 { 608 struct bpf_offloaded_map *offmap = map_to_offmap(map); 609 int ret = -ENODEV; 610 611 down_read(&bpf_devs_lock); 612 if (offmap->netdev) 613 ret = offmap->dev_ops->map_delete_elem(offmap, key); 614 up_read(&bpf_devs_lock); 615 616 return ret; 617 } 618 619 int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key) 620 { 621 struct bpf_offloaded_map *offmap = map_to_offmap(map); 622 int ret = -ENODEV; 623 624 down_read(&bpf_devs_lock); 625 if (offmap->netdev) 626 ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key); 627 up_read(&bpf_devs_lock); 628 629 return ret; 630 } 631 632 struct ns_get_path_bpf_map_args { 633 struct bpf_offloaded_map *offmap; 634 struct bpf_map_info *info; 635 }; 636 637 static struct ns_common *bpf_map_offload_info_fill_ns(void *private_data) 638 { 639 struct ns_get_path_bpf_map_args *args = private_data; 640 struct ns_common *ns; 641 struct net *net; 642 643 rtnl_lock(); 644 down_read(&bpf_devs_lock); 645 646 if (args->offmap->netdev) { 647 args->info->ifindex = args->offmap->netdev->ifindex; 648 net = dev_net(args->offmap->netdev); 649 get_net(net); 650 ns = &net->ns; 651 } else { 652 args->info->ifindex = 0; 653 ns = NULL; 654 } 655 656 up_read(&bpf_devs_lock); 657 rtnl_unlock(); 658 659 return ns; 660 } 661 662 int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map) 663 { 664 struct ns_get_path_bpf_map_args args = { 665 .offmap = map_to_offmap(map), 666 .info = info, 667 }; 668 struct inode *ns_inode; 669 struct path ns_path; 670 int res; 671 672 res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args); 673 if (res) { 674 if (!info->ifindex) 675 return -ENODEV; 676 return res; 677 } 678 679 ns_inode = ns_path.dentry->d_inode; 680 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 681 info->netns_ino = ns_inode->i_ino; 682 path_put(&ns_path); 683 684 return 0; 685 } 686 687 static bool __bpf_offload_dev_match(struct bpf_prog *prog, 688 struct net_device *netdev) 689 { 690 struct bpf_offload_netdev *ondev1, *ondev2; 691 struct bpf_prog_offload *offload; 692 693 if (!bpf_prog_is_dev_bound(prog->aux)) 694 return false; 695 696 offload = prog->aux->offload; 697 if (!offload) 698 return false; 699 if (offload->netdev == netdev) 700 return true; 701 702 ondev1 = bpf_offload_find_netdev(offload->netdev); 703 ondev2 = bpf_offload_find_netdev(netdev); 704 705 return ondev1 && ondev2 && ondev1->offdev == ondev2->offdev; 706 } 707 708 bool bpf_offload_dev_match(struct bpf_prog *prog, struct net_device *netdev) 709 { 710 bool ret; 711 712 down_read(&bpf_devs_lock); 713 ret = __bpf_offload_dev_match(prog, netdev); 714 up_read(&bpf_devs_lock); 715 716 return ret; 717 } 718 EXPORT_SYMBOL_GPL(bpf_offload_dev_match); 719 720 bool bpf_prog_dev_bound_match(const struct bpf_prog *lhs, const struct bpf_prog *rhs) 721 { 722 bool ret; 723 724 if (bpf_prog_is_offloaded(lhs->aux) != bpf_prog_is_offloaded(rhs->aux)) 725 return false; 726 727 down_read(&bpf_devs_lock); 728 ret = lhs->aux->offload && rhs->aux->offload && 729 lhs->aux->offload->netdev && 730 lhs->aux->offload->netdev == rhs->aux->offload->netdev; 731 up_read(&bpf_devs_lock); 732 733 return ret; 734 } 735 736 bool bpf_offload_prog_map_match(struct bpf_prog *prog, struct bpf_map *map) 737 { 738 struct bpf_offloaded_map *offmap; 739 bool ret; 740 741 if (!bpf_map_is_offloaded(map)) 742 return bpf_map_offload_neutral(map); 743 offmap = map_to_offmap(map); 744 745 down_read(&bpf_devs_lock); 746 ret = __bpf_offload_dev_match(prog, offmap->netdev); 747 up_read(&bpf_devs_lock); 748 749 return ret; 750 } 751 752 int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev, 753 struct net_device *netdev) 754 { 755 int err; 756 757 down_write(&bpf_devs_lock); 758 err = __bpf_offload_dev_netdev_register(offdev, netdev); 759 up_write(&bpf_devs_lock); 760 return err; 761 } 762 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_register); 763 764 void bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev, 765 struct net_device *netdev) 766 { 767 down_write(&bpf_devs_lock); 768 __bpf_offload_dev_netdev_unregister(offdev, netdev); 769 up_write(&bpf_devs_lock); 770 } 771 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_unregister); 772 773 struct bpf_offload_dev * 774 bpf_offload_dev_create(const struct bpf_prog_offload_ops *ops, void *priv) 775 { 776 struct bpf_offload_dev *offdev; 777 778 offdev = kzalloc(sizeof(*offdev), GFP_KERNEL); 779 if (!offdev) 780 return ERR_PTR(-ENOMEM); 781 782 offdev->ops = ops; 783 offdev->priv = priv; 784 INIT_LIST_HEAD(&offdev->netdevs); 785 786 return offdev; 787 } 788 EXPORT_SYMBOL_GPL(bpf_offload_dev_create); 789 790 void bpf_offload_dev_destroy(struct bpf_offload_dev *offdev) 791 { 792 WARN_ON(!list_empty(&offdev->netdevs)); 793 kfree(offdev); 794 } 795 EXPORT_SYMBOL_GPL(bpf_offload_dev_destroy); 796 797 void *bpf_offload_dev_priv(struct bpf_offload_dev *offdev) 798 { 799 return offdev->priv; 800 } 801 EXPORT_SYMBOL_GPL(bpf_offload_dev_priv); 802 803 void bpf_dev_bound_netdev_unregister(struct net_device *dev) 804 { 805 struct bpf_offload_netdev *ondev; 806 807 ASSERT_RTNL(); 808 809 down_write(&bpf_devs_lock); 810 ondev = bpf_offload_find_netdev(dev); 811 if (ondev && !ondev->offdev) 812 __bpf_offload_dev_netdev_unregister(NULL, ondev->netdev); 813 up_write(&bpf_devs_lock); 814 } 815 816 int bpf_dev_bound_kfunc_check(struct bpf_verifier_log *log, 817 struct bpf_prog_aux *prog_aux) 818 { 819 if (!bpf_prog_is_dev_bound(prog_aux)) { 820 bpf_log(log, "metadata kfuncs require device-bound program\n"); 821 return -EINVAL; 822 } 823 824 if (bpf_prog_is_offloaded(prog_aux)) { 825 bpf_log(log, "metadata kfuncs can't be offloaded\n"); 826 return -EINVAL; 827 } 828 829 return 0; 830 } 831 832 void *bpf_dev_bound_resolve_kfunc(struct bpf_prog *prog, u32 func_id) 833 { 834 const struct xdp_metadata_ops *ops; 835 void *p = NULL; 836 837 /* We don't hold bpf_devs_lock while resolving several 838 * kfuncs and can race with the unregister_netdevice(). 839 * We rely on bpf_dev_bound_match() check at attach 840 * to render this program unusable. 841 */ 842 down_read(&bpf_devs_lock); 843 if (!prog->aux->offload) 844 goto out; 845 846 ops = prog->aux->offload->netdev->xdp_metadata_ops; 847 if (!ops) 848 goto out; 849 850 if (func_id == bpf_xdp_metadata_kfunc_id(XDP_METADATA_KFUNC_RX_TIMESTAMP)) 851 p = ops->xmo_rx_timestamp; 852 else if (func_id == bpf_xdp_metadata_kfunc_id(XDP_METADATA_KFUNC_RX_HASH)) 853 p = ops->xmo_rx_hash; 854 out: 855 up_read(&bpf_devs_lock); 856 857 return p; 858 } 859 860 static int __init bpf_offload_init(void) 861 { 862 return rhashtable_init(&offdevs, &offdevs_params); 863 } 864 865 core_initcall(bpf_offload_init); 866