1// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) 2/* Copyright (C) 2016-2018 Netronome Systems, Inc. */ 3 4/* 5 * nfp_net_offload.c 6 * Netronome network device driver: TC offload functions for PF and VF 7 */ 8 9#define pr_fmt(fmt) "NFP net bpf: " fmt 10 11#include <linux/bpf.h> 12#include <linux/kernel.h> 13#include <linux/netdevice.h> 14#include <linux/pci.h> 15#include <linux/jiffies.h> 16#include <linux/timer.h> 17#include <linux/list.h> 18#include <linux/mm.h> 19 20#include <net/pkt_cls.h> 21#include <net/tc_act/tc_gact.h> 22#include <net/tc_act/tc_mirred.h> 23 24#include "main.h" 25#include "../ccm.h" 26#include "../nfp_app.h" 27#include "../nfp_net_ctrl.h" 28#include "../nfp_net.h" 29 30static int 31nfp_map_ptr_record(struct nfp_app_bpf *bpf, struct nfp_prog *nfp_prog, 32 struct bpf_map *map) 33{ 34 struct nfp_bpf_neutral_map *record; 35 int err; 36 37 /* Reuse path - other offloaded program is already tracking this map. */ 38 record = rhashtable_lookup_fast(&bpf->maps_neutral, &map->id, 39 nfp_bpf_maps_neutral_params); 40 if (record) { 41 nfp_prog->map_records[nfp_prog->map_records_cnt++] = record; 42 record->count++; 43 return 0; 44 } 45 46 /* Grab a single ref to the map for our record. The prog destroy ndo 47 * happens after free_used_maps(). 48 */ 49 bpf_map_inc(map); 50 51 record = kmalloc(sizeof(*record), GFP_KERNEL); 52 if (!record) { 53 err = -ENOMEM; 54 goto err_map_put; 55 } 56 57 record->ptr = map; 58 record->map_id = map->id; 59 record->count = 1; 60 61 err = rhashtable_insert_fast(&bpf->maps_neutral, &record->l, 62 nfp_bpf_maps_neutral_params); 63 if (err) 64 goto err_free_rec; 65 66 nfp_prog->map_records[nfp_prog->map_records_cnt++] = record; 67 68 return 0; 69 70err_free_rec: 71 kfree(record); 72err_map_put: 73 bpf_map_put(map); 74 return err; 75} 76 77static void 78nfp_map_ptrs_forget(struct nfp_app_bpf *bpf, struct nfp_prog *nfp_prog) 79{ 80 bool freed = false; 81 int i; 82 83 for (i = 0; i < nfp_prog->map_records_cnt; i++) { 84 if (--nfp_prog->map_records[i]->count) { 85 nfp_prog->map_records[i] = NULL; 86 continue; 87 } 88 89 WARN_ON(rhashtable_remove_fast(&bpf->maps_neutral, 90 &nfp_prog->map_records[i]->l, 91 nfp_bpf_maps_neutral_params)); 92 freed = true; 93 } 94 95 if (freed) { 96 synchronize_rcu(); 97 98 for (i = 0; i < nfp_prog->map_records_cnt; i++) 99 if (nfp_prog->map_records[i]) { 100 bpf_map_put(nfp_prog->map_records[i]->ptr); 101 kfree(nfp_prog->map_records[i]); 102 } 103 } 104 105 kfree(nfp_prog->map_records); 106 nfp_prog->map_records = NULL; 107 nfp_prog->map_records_cnt = 0; 108} 109 110static int 111nfp_map_ptrs_record(struct nfp_app_bpf *bpf, struct nfp_prog *nfp_prog, 112 struct bpf_prog *prog) 113{ 114 int i, cnt, err = 0; 115 116 mutex_lock(&prog->aux->used_maps_mutex); 117 118 /* Quickly count the maps we will have to remember */ 119 cnt = 0; 120 for (i = 0; i < prog->aux->used_map_cnt; i++) 121 if (bpf_map_offload_neutral(prog->aux->used_maps[i])) 122 cnt++; 123 if (!cnt) 124 goto out; 125 126 nfp_prog->map_records = kmalloc_array(cnt, 127 sizeof(nfp_prog->map_records[0]), 128 GFP_KERNEL); 129 if (!nfp_prog->map_records) { 130 err = -ENOMEM; 131 goto out; 132 } 133 134 for (i = 0; i < prog->aux->used_map_cnt; i++) 135 if (bpf_map_offload_neutral(prog->aux->used_maps[i])) { 136 err = nfp_map_ptr_record(bpf, nfp_prog, 137 prog->aux->used_maps[i]); 138 if (err) { 139 nfp_map_ptrs_forget(bpf, nfp_prog); 140 goto out; 141 } 142 } 143 WARN_ON(cnt != nfp_prog->map_records_cnt); 144 145out: 146 mutex_unlock(&prog->aux->used_maps_mutex); 147 return err; 148} 149 150static int 151nfp_prog_prepare(struct nfp_prog *nfp_prog, const struct bpf_insn *prog, 152 unsigned int cnt) 153{ 154 struct nfp_insn_meta *meta; 155 unsigned int i; 156 157 for (i = 0; i < cnt; i++) { 158 meta = kzalloc(sizeof(*meta), GFP_KERNEL); 159 if (!meta) 160 return -ENOMEM; 161 162 meta->insn = prog[i]; 163 meta->n = i; 164 if (is_mbpf_alu(meta)) { 165 meta->umin_src = U64_MAX; 166 meta->umin_dst = U64_MAX; 167 } 168 169 list_add_tail(&meta->l, &nfp_prog->insns); 170 } 171 nfp_prog->n_insns = cnt; 172 173 nfp_bpf_jit_prepare(nfp_prog); 174 175 return 0; 176} 177 178static void nfp_prog_free(struct nfp_prog *nfp_prog) 179{ 180 struct nfp_insn_meta *meta, *tmp; 181 182 kfree(nfp_prog->subprog); 183 184 list_for_each_entry_safe(meta, tmp, &nfp_prog->insns, l) { 185 list_del(&meta->l); 186 kfree(meta); 187 } 188 kfree(nfp_prog); 189} 190 191static int nfp_bpf_verifier_prep(struct bpf_prog *prog) 192{ 193 struct nfp_prog *nfp_prog; 194 int ret; 195 196 nfp_prog = kzalloc(sizeof(*nfp_prog), GFP_KERNEL); 197 if (!nfp_prog) 198 return -ENOMEM; 199 prog->aux->offload->dev_priv = nfp_prog; 200 201 INIT_LIST_HEAD(&nfp_prog->insns); 202 nfp_prog->type = prog->type; 203 nfp_prog->bpf = bpf_offload_dev_priv(prog->aux->offload->offdev); 204 205 ret = nfp_prog_prepare(nfp_prog, prog->insnsi, prog->len); 206 if (ret) 207 goto err_free; 208 209 nfp_prog->verifier_meta = nfp_prog_first_meta(nfp_prog); 210 211 return 0; 212 213err_free: 214 nfp_prog_free(nfp_prog); 215 216 return ret; 217} 218 219static int nfp_bpf_translate(struct bpf_prog *prog) 220{ 221 struct nfp_net *nn = netdev_priv(prog->aux->offload->netdev); 222 struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv; 223 unsigned int max_instr; 224 int err; 225 226 /* We depend on dead code elimination succeeding */ 227 if (prog->aux->offload->opt_failed) 228 return -EINVAL; 229 230 max_instr = nn_readw(nn, NFP_NET_CFG_BPF_MAX_LEN); 231 nfp_prog->__prog_alloc_len = max_instr * sizeof(u64); 232 233 nfp_prog->prog = kvmalloc(nfp_prog->__prog_alloc_len, GFP_KERNEL); 234 if (!nfp_prog->prog) 235 return -ENOMEM; 236 237 err = nfp_bpf_jit(nfp_prog); 238 if (err) 239 return err; 240 241 prog->aux->offload->jited_len = nfp_prog->prog_len * sizeof(u64); 242 prog->aux->offload->jited_image = nfp_prog->prog; 243 244 return nfp_map_ptrs_record(nfp_prog->bpf, nfp_prog, prog); 245} 246 247static void nfp_bpf_destroy(struct bpf_prog *prog) 248{ 249 struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv; 250 251 kvfree(nfp_prog->prog); 252 nfp_map_ptrs_forget(nfp_prog->bpf, nfp_prog); 253 nfp_prog_free(nfp_prog); 254} 255 256/* Atomic engine requires values to be in big endian, we need to byte swap 257 * the value words used with xadd. 258 */ 259static void nfp_map_bpf_byte_swap(struct nfp_bpf_map *nfp_map, void *value) 260{ 261 u32 *word = value; 262 unsigned int i; 263 264 for (i = 0; i < DIV_ROUND_UP(nfp_map->offmap->map.value_size, 4); i++) 265 if (nfp_map->use_map[i].type == NFP_MAP_USE_ATOMIC_CNT) 266 word[i] = (__force u32)cpu_to_be32(word[i]); 267} 268 269/* Mark value as unsafely initialized in case it becomes atomic later 270 * and we didn't byte swap something non-byte swap neutral. 271 */ 272static void 273nfp_map_bpf_byte_swap_record(struct nfp_bpf_map *nfp_map, void *value) 274{ 275 u32 *word = value; 276 unsigned int i; 277 278 for (i = 0; i < DIV_ROUND_UP(nfp_map->offmap->map.value_size, 4); i++) 279 if (nfp_map->use_map[i].type == NFP_MAP_UNUSED && 280 word[i] != (__force u32)cpu_to_be32(word[i])) 281 nfp_map->use_map[i].non_zero_update = 1; 282} 283 284static int 285nfp_bpf_map_lookup_entry(struct bpf_offloaded_map *offmap, 286 void *key, void *value) 287{ 288 int err; 289 290 err = nfp_bpf_ctrl_lookup_entry(offmap, key, value); 291 if (err) 292 return err; 293 294 nfp_map_bpf_byte_swap(offmap->dev_priv, value); 295 return 0; 296} 297 298static int 299nfp_bpf_map_update_entry(struct bpf_offloaded_map *offmap, 300 void *key, void *value, u64 flags) 301{ 302 nfp_map_bpf_byte_swap(offmap->dev_priv, value); 303 nfp_map_bpf_byte_swap_record(offmap->dev_priv, value); 304 return nfp_bpf_ctrl_update_entry(offmap, key, value, flags); 305} 306 307static int 308nfp_bpf_map_get_next_key(struct bpf_offloaded_map *offmap, 309 void *key, void *next_key) 310{ 311 if (!key) 312 return nfp_bpf_ctrl_getfirst_entry(offmap, next_key); 313 return nfp_bpf_ctrl_getnext_entry(offmap, key, next_key); 314} 315 316static int 317nfp_bpf_map_delete_elem(struct bpf_offloaded_map *offmap, void *key) 318{ 319 if (offmap->map.map_type == BPF_MAP_TYPE_ARRAY) 320 return -EINVAL; 321 return nfp_bpf_ctrl_del_entry(offmap, key); 322} 323 324static const struct bpf_map_dev_ops nfp_bpf_map_ops = { 325 .map_get_next_key = nfp_bpf_map_get_next_key, 326 .map_lookup_elem = nfp_bpf_map_lookup_entry, 327 .map_update_elem = nfp_bpf_map_update_entry, 328 .map_delete_elem = nfp_bpf_map_delete_elem, 329}; 330 331static int 332nfp_bpf_map_alloc(struct nfp_app_bpf *bpf, struct bpf_offloaded_map *offmap) 333{ 334 struct nfp_bpf_map *nfp_map; 335 unsigned int use_map_size; 336 long long int res; 337 338 if (!bpf->maps.types) 339 return -EOPNOTSUPP; 340 341 if (offmap->map.map_flags || 342 offmap->map.numa_node != NUMA_NO_NODE) { 343 pr_info("map flags are not supported\n"); 344 return -EINVAL; 345 } 346 347 if (!(bpf->maps.types & 1 << offmap->map.map_type)) { 348 pr_info("map type not supported\n"); 349 return -EOPNOTSUPP; 350 } 351 if (bpf->maps.max_maps == bpf->maps_in_use) { 352 pr_info("too many maps for a device\n"); 353 return -ENOMEM; 354 } 355 if (bpf->maps.max_elems - bpf->map_elems_in_use < 356 offmap->map.max_entries) { 357 pr_info("map with too many elements: %u, left: %u\n", 358 offmap->map.max_entries, 359 bpf->maps.max_elems - bpf->map_elems_in_use); 360 return -ENOMEM; 361 } 362 363 if (round_up(offmap->map.key_size, 8) + 364 round_up(offmap->map.value_size, 8) > bpf->maps.max_elem_sz) { 365 pr_info("map elements too large: %u, FW max element size (key+value): %u\n", 366 round_up(offmap->map.key_size, 8) + 367 round_up(offmap->map.value_size, 8), 368 bpf->maps.max_elem_sz); 369 return -ENOMEM; 370 } 371 if (offmap->map.key_size > bpf->maps.max_key_sz) { 372 pr_info("map key size %u, FW max is %u\n", 373 offmap->map.key_size, bpf->maps.max_key_sz); 374 return -ENOMEM; 375 } 376 if (offmap->map.value_size > bpf->maps.max_val_sz) { 377 pr_info("map value size %u, FW max is %u\n", 378 offmap->map.value_size, bpf->maps.max_val_sz); 379 return -ENOMEM; 380 } 381 382 use_map_size = DIV_ROUND_UP(offmap->map.value_size, 4) * 383 sizeof_field(struct nfp_bpf_map, use_map[0]); 384 385 nfp_map = kzalloc(sizeof(*nfp_map) + use_map_size, GFP_USER); 386 if (!nfp_map) 387 return -ENOMEM; 388 389 offmap->dev_priv = nfp_map; 390 nfp_map->offmap = offmap; 391 nfp_map->bpf = bpf; 392 spin_lock_init(&nfp_map->cache_lock); 393 394 res = nfp_bpf_ctrl_alloc_map(bpf, &offmap->map); 395 if (res < 0) { 396 kfree(nfp_map); 397 return res; 398 } 399 400 nfp_map->tid = res; 401 offmap->dev_ops = &nfp_bpf_map_ops; 402 bpf->maps_in_use++; 403 bpf->map_elems_in_use += offmap->map.max_entries; 404 list_add_tail(&nfp_map->l, &bpf->map_list); 405 406 return 0; 407} 408 409static int 410nfp_bpf_map_free(struct nfp_app_bpf *bpf, struct bpf_offloaded_map *offmap) 411{ 412 struct nfp_bpf_map *nfp_map = offmap->dev_priv; 413 414 nfp_bpf_ctrl_free_map(bpf, nfp_map); 415 dev_consume_skb_any(nfp_map->cache); 416 WARN_ON_ONCE(nfp_map->cache_blockers); 417 list_del_init(&nfp_map->l); 418 bpf->map_elems_in_use -= offmap->map.max_entries; 419 bpf->maps_in_use--; 420 kfree(nfp_map); 421 422 return 0; 423} 424 425int nfp_ndo_bpf(struct nfp_app *app, struct nfp_net *nn, struct netdev_bpf *bpf) 426{ 427 switch (bpf->command) { 428 case BPF_OFFLOAD_MAP_ALLOC: 429 return nfp_bpf_map_alloc(app->priv, bpf->offmap); 430 case BPF_OFFLOAD_MAP_FREE: 431 return nfp_bpf_map_free(app->priv, bpf->offmap); 432 default: 433 return -EINVAL; 434 } 435} 436 437static unsigned long 438nfp_bpf_perf_event_copy(void *dst, const void *src, 439 unsigned long off, unsigned long len) 440{ 441 memcpy(dst, src + off, len); 442 return 0; 443} 444 445int nfp_bpf_event_output(struct nfp_app_bpf *bpf, const void *data, 446 unsigned int len) 447{ 448 struct cmsg_bpf_event *cbe = (void *)data; 449 struct nfp_bpf_neutral_map *record; 450 u32 pkt_size, data_size, map_id; 451 u64 map_id_full; 452 453 if (len < sizeof(struct cmsg_bpf_event)) 454 return -EINVAL; 455 456 pkt_size = be32_to_cpu(cbe->pkt_size); 457 data_size = be32_to_cpu(cbe->data_size); 458 map_id_full = be64_to_cpu(cbe->map_ptr); 459 map_id = map_id_full; 460 461 if (len < sizeof(struct cmsg_bpf_event) + pkt_size + data_size) 462 return -EINVAL; 463 if (cbe->hdr.ver != NFP_CCM_ABI_VERSION) 464 return -EINVAL; 465 466 rcu_read_lock(); 467 record = rhashtable_lookup(&bpf->maps_neutral, &map_id, 468 nfp_bpf_maps_neutral_params); 469 if (!record || map_id_full > U32_MAX) { 470 rcu_read_unlock(); 471 cmsg_warn(bpf, "perf event: map id %lld (0x%llx) not recognized, dropping event\n", 472 map_id_full, map_id_full); 473 return -EINVAL; 474 } 475 476 bpf_event_output(record->ptr, be32_to_cpu(cbe->cpu_id), 477 &cbe->data[round_up(pkt_size, 4)], data_size, 478 cbe->data, pkt_size, nfp_bpf_perf_event_copy); 479 rcu_read_unlock(); 480 481 return 0; 482} 483 484bool nfp_bpf_offload_check_mtu(struct nfp_net *nn, struct bpf_prog *prog, 485 unsigned int mtu) 486{ 487 unsigned int fw_mtu, pkt_off; 488 489 fw_mtu = nn_readb(nn, NFP_NET_CFG_BPF_INL_MTU) * 64 - 32; 490 pkt_off = min(prog->aux->max_pkt_offset, mtu); 491 492 return fw_mtu < pkt_off; 493} 494 495static int 496nfp_net_bpf_load(struct nfp_net *nn, struct bpf_prog *prog, 497 struct netlink_ext_ack *extack) 498{ 499 struct nfp_prog *nfp_prog = prog->aux->offload->dev_priv; 500 unsigned int max_stack, max_prog_len; 501 dma_addr_t dma_addr; 502 void *img; 503 int err; 504 505 if (nfp_bpf_offload_check_mtu(nn, prog, nn->dp.netdev->mtu)) { 506 NL_SET_ERR_MSG_MOD(extack, "BPF offload not supported with potential packet access beyond HW packet split boundary"); 507 return -EOPNOTSUPP; 508 } 509 510 max_stack = nn_readb(nn, NFP_NET_CFG_BPF_STACK_SZ) * 64; 511 if (nfp_prog->stack_size > max_stack) { 512 NL_SET_ERR_MSG_MOD(extack, "stack too large"); 513 return -EOPNOTSUPP; 514 } 515 516 max_prog_len = nn_readw(nn, NFP_NET_CFG_BPF_MAX_LEN); 517 if (nfp_prog->prog_len > max_prog_len) { 518 NL_SET_ERR_MSG_MOD(extack, "program too long"); 519 return -EOPNOTSUPP; 520 } 521 522 img = nfp_bpf_relo_for_vnic(nfp_prog, nn->app_priv); 523 if (IS_ERR(img)) 524 return PTR_ERR(img); 525 526 dma_addr = dma_map_single(nn->dp.dev, img, 527 nfp_prog->prog_len * sizeof(u64), 528 DMA_TO_DEVICE); 529 if (dma_mapping_error(nn->dp.dev, dma_addr)) { 530 kfree(img); 531 return -ENOMEM; 532 } 533 534 nn_writew(nn, NFP_NET_CFG_BPF_SIZE, nfp_prog->prog_len); 535 nn_writeq(nn, NFP_NET_CFG_BPF_ADDR, dma_addr); 536 537 /* Load up the JITed code */ 538 err = nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_BPF); 539 if (err) 540 NL_SET_ERR_MSG_MOD(extack, 541 "FW command error while loading BPF"); 542 543 dma_unmap_single(nn->dp.dev, dma_addr, nfp_prog->prog_len * sizeof(u64), 544 DMA_TO_DEVICE); 545 kfree(img); 546 547 return err; 548} 549 550static void 551nfp_net_bpf_start(struct nfp_net *nn, struct netlink_ext_ack *extack) 552{ 553 int err; 554 555 /* Enable passing packets through BPF function */ 556 nn->dp.ctrl |= NFP_NET_CFG_CTRL_BPF; 557 nn_writel(nn, NFP_NET_CFG_CTRL, nn->dp.ctrl); 558 err = nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_GEN); 559 if (err) 560 NL_SET_ERR_MSG_MOD(extack, 561 "FW command error while enabling BPF"); 562} 563 564static int nfp_net_bpf_stop(struct nfp_net *nn) 565{ 566 if (!(nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF)) 567 return 0; 568 569 nn->dp.ctrl &= ~NFP_NET_CFG_CTRL_BPF; 570 nn_writel(nn, NFP_NET_CFG_CTRL, nn->dp.ctrl); 571 572 return nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_GEN); 573} 574 575int nfp_net_bpf_offload(struct nfp_net *nn, struct bpf_prog *prog, 576 bool old_prog, struct netlink_ext_ack *extack) 577{ 578 int err; 579 580 if (prog && !bpf_offload_dev_match(prog, nn->dp.netdev)) 581 return -EINVAL; 582 583 if (prog && old_prog) { 584 u8 cap; 585 586 cap = nn_readb(nn, NFP_NET_CFG_BPF_CAP); 587 if (!(cap & NFP_NET_BPF_CAP_RELO)) { 588 NL_SET_ERR_MSG_MOD(extack, 589 "FW does not support live reload"); 590 return -EBUSY; 591 } 592 } 593 594 /* Something else is loaded, different program type? */ 595 if (!old_prog && nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF) 596 return -EBUSY; 597 598 if (old_prog && !prog) 599 return nfp_net_bpf_stop(nn); 600 601 err = nfp_net_bpf_load(nn, prog, extack); 602 if (err) 603 return err; 604 605 if (!old_prog) 606 nfp_net_bpf_start(nn, extack); 607 608 return 0; 609} 610 611const struct bpf_prog_offload_ops nfp_bpf_dev_ops = { 612 .insn_hook = nfp_verify_insn, 613 .finalize = nfp_bpf_finalize, 614 .replace_insn = nfp_bpf_opt_replace_insn, 615 .remove_insns = nfp_bpf_opt_remove_insns, 616 .prepare = nfp_bpf_verifier_prep, 617 .translate = nfp_bpf_translate, 618 .destroy = nfp_bpf_destroy, 619}; 620