xref: /openbmc/linux/tools/lib/bpf/bpf.c (revision 023e4163)
1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
2 
3 /*
4  * common eBPF ELF operations.
5  *
6  * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
7  * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
8  * Copyright (C) 2015 Huawei Inc.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation;
13  * version 2.1 of the License (not later!)
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with this program; if not,  see <http://www.gnu.org/licenses>
22  */
23 
24 #include <stdlib.h>
25 #include <string.h>
26 #include <memory.h>
27 #include <unistd.h>
28 #include <asm/unistd.h>
29 #include <linux/bpf.h>
30 #include "bpf.h"
31 #include "libbpf.h"
32 #include <errno.h>
33 
34 /*
35  * When building perf, unistd.h is overridden. __NR_bpf is
36  * required to be defined explicitly.
37  */
38 #ifndef __NR_bpf
39 # if defined(__i386__)
40 #  define __NR_bpf 357
41 # elif defined(__x86_64__)
42 #  define __NR_bpf 321
43 # elif defined(__aarch64__)
44 #  define __NR_bpf 280
45 # elif defined(__sparc__)
46 #  define __NR_bpf 349
47 # elif defined(__s390__)
48 #  define __NR_bpf 351
49 # else
50 #  error __NR_bpf not defined. libbpf does not support your arch.
51 # endif
52 #endif
53 
54 #ifndef min
55 #define min(x, y) ((x) < (y) ? (x) : (y))
56 #endif
57 
58 static inline __u64 ptr_to_u64(const void *ptr)
59 {
60 	return (__u64) (unsigned long) ptr;
61 }
62 
63 static inline int sys_bpf(enum bpf_cmd cmd, union bpf_attr *attr,
64 			  unsigned int size)
65 {
66 	return syscall(__NR_bpf, cmd, attr, size);
67 }
68 
69 static inline int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size)
70 {
71 	int fd;
72 
73 	do {
74 		fd = sys_bpf(BPF_PROG_LOAD, attr, size);
75 	} while (fd < 0 && errno == EAGAIN);
76 
77 	return fd;
78 }
79 
80 int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr)
81 {
82 	__u32 name_len = create_attr->name ? strlen(create_attr->name) : 0;
83 	union bpf_attr attr;
84 
85 	memset(&attr, '\0', sizeof(attr));
86 
87 	attr.map_type = create_attr->map_type;
88 	attr.key_size = create_attr->key_size;
89 	attr.value_size = create_attr->value_size;
90 	attr.max_entries = create_attr->max_entries;
91 	attr.map_flags = create_attr->map_flags;
92 	memcpy(attr.map_name, create_attr->name,
93 	       min(name_len, BPF_OBJ_NAME_LEN - 1));
94 	attr.numa_node = create_attr->numa_node;
95 	attr.btf_fd = create_attr->btf_fd;
96 	attr.btf_key_type_id = create_attr->btf_key_type_id;
97 	attr.btf_value_type_id = create_attr->btf_value_type_id;
98 	attr.map_ifindex = create_attr->map_ifindex;
99 	attr.inner_map_fd = create_attr->inner_map_fd;
100 
101 	return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
102 }
103 
104 int bpf_create_map_node(enum bpf_map_type map_type, const char *name,
105 			int key_size, int value_size, int max_entries,
106 			__u32 map_flags, int node)
107 {
108 	struct bpf_create_map_attr map_attr = {};
109 
110 	map_attr.name = name;
111 	map_attr.map_type = map_type;
112 	map_attr.map_flags = map_flags;
113 	map_attr.key_size = key_size;
114 	map_attr.value_size = value_size;
115 	map_attr.max_entries = max_entries;
116 	if (node >= 0) {
117 		map_attr.numa_node = node;
118 		map_attr.map_flags |= BPF_F_NUMA_NODE;
119 	}
120 
121 	return bpf_create_map_xattr(&map_attr);
122 }
123 
124 int bpf_create_map(enum bpf_map_type map_type, int key_size,
125 		   int value_size, int max_entries, __u32 map_flags)
126 {
127 	struct bpf_create_map_attr map_attr = {};
128 
129 	map_attr.map_type = map_type;
130 	map_attr.map_flags = map_flags;
131 	map_attr.key_size = key_size;
132 	map_attr.value_size = value_size;
133 	map_attr.max_entries = max_entries;
134 
135 	return bpf_create_map_xattr(&map_attr);
136 }
137 
138 int bpf_create_map_name(enum bpf_map_type map_type, const char *name,
139 			int key_size, int value_size, int max_entries,
140 			__u32 map_flags)
141 {
142 	struct bpf_create_map_attr map_attr = {};
143 
144 	map_attr.name = name;
145 	map_attr.map_type = map_type;
146 	map_attr.map_flags = map_flags;
147 	map_attr.key_size = key_size;
148 	map_attr.value_size = value_size;
149 	map_attr.max_entries = max_entries;
150 
151 	return bpf_create_map_xattr(&map_attr);
152 }
153 
154 int bpf_create_map_in_map_node(enum bpf_map_type map_type, const char *name,
155 			       int key_size, int inner_map_fd, int max_entries,
156 			       __u32 map_flags, int node)
157 {
158 	__u32 name_len = name ? strlen(name) : 0;
159 	union bpf_attr attr;
160 
161 	memset(&attr, '\0', sizeof(attr));
162 
163 	attr.map_type = map_type;
164 	attr.key_size = key_size;
165 	attr.value_size = 4;
166 	attr.inner_map_fd = inner_map_fd;
167 	attr.max_entries = max_entries;
168 	attr.map_flags = map_flags;
169 	memcpy(attr.map_name, name, min(name_len, BPF_OBJ_NAME_LEN - 1));
170 
171 	if (node >= 0) {
172 		attr.map_flags |= BPF_F_NUMA_NODE;
173 		attr.numa_node = node;
174 	}
175 
176 	return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
177 }
178 
179 int bpf_create_map_in_map(enum bpf_map_type map_type, const char *name,
180 			  int key_size, int inner_map_fd, int max_entries,
181 			  __u32 map_flags)
182 {
183 	return bpf_create_map_in_map_node(map_type, name, key_size,
184 					  inner_map_fd, max_entries, map_flags,
185 					  -1);
186 }
187 
188 static void *
189 alloc_zero_tailing_info(const void *orecord, __u32 cnt,
190 			__u32 actual_rec_size, __u32 expected_rec_size)
191 {
192 	__u64 info_len = actual_rec_size * cnt;
193 	void *info, *nrecord;
194 	int i;
195 
196 	info = malloc(info_len);
197 	if (!info)
198 		return NULL;
199 
200 	/* zero out bytes kernel does not understand */
201 	nrecord = info;
202 	for (i = 0; i < cnt; i++) {
203 		memcpy(nrecord, orecord, expected_rec_size);
204 		memset(nrecord + expected_rec_size, 0,
205 		       actual_rec_size - expected_rec_size);
206 		orecord += actual_rec_size;
207 		nrecord += actual_rec_size;
208 	}
209 
210 	return info;
211 }
212 
213 int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
214 			   char *log_buf, size_t log_buf_sz)
215 {
216 	void *finfo = NULL, *linfo = NULL;
217 	union bpf_attr attr;
218 	__u32 log_level;
219 	__u32 name_len;
220 	int fd;
221 
222 	if (!load_attr || !log_buf != !log_buf_sz)
223 		return -EINVAL;
224 
225 	log_level = load_attr->log_level;
226 	if (log_level > 2 || (log_level && !log_buf))
227 		return -EINVAL;
228 
229 	name_len = load_attr->name ? strlen(load_attr->name) : 0;
230 
231 	memset(&attr, 0, sizeof(attr));
232 	attr.prog_type = load_attr->prog_type;
233 	attr.expected_attach_type = load_attr->expected_attach_type;
234 	attr.insn_cnt = (__u32)load_attr->insns_cnt;
235 	attr.insns = ptr_to_u64(load_attr->insns);
236 	attr.license = ptr_to_u64(load_attr->license);
237 
238 	attr.log_level = log_level;
239 	if (log_level) {
240 		attr.log_buf = ptr_to_u64(log_buf);
241 		attr.log_size = log_buf_sz;
242 	} else {
243 		attr.log_buf = ptr_to_u64(NULL);
244 		attr.log_size = 0;
245 	}
246 
247 	attr.kern_version = load_attr->kern_version;
248 	attr.prog_ifindex = load_attr->prog_ifindex;
249 	attr.prog_btf_fd = load_attr->prog_btf_fd;
250 	attr.func_info_rec_size = load_attr->func_info_rec_size;
251 	attr.func_info_cnt = load_attr->func_info_cnt;
252 	attr.func_info = ptr_to_u64(load_attr->func_info);
253 	attr.line_info_rec_size = load_attr->line_info_rec_size;
254 	attr.line_info_cnt = load_attr->line_info_cnt;
255 	attr.line_info = ptr_to_u64(load_attr->line_info);
256 	memcpy(attr.prog_name, load_attr->name,
257 	       min(name_len, BPF_OBJ_NAME_LEN - 1));
258 
259 	fd = sys_bpf_prog_load(&attr, sizeof(attr));
260 	if (fd >= 0)
261 		return fd;
262 
263 	/* After bpf_prog_load, the kernel may modify certain attributes
264 	 * to give user space a hint how to deal with loading failure.
265 	 * Check to see whether we can make some changes and load again.
266 	 */
267 	while (errno == E2BIG && (!finfo || !linfo)) {
268 		if (!finfo && attr.func_info_cnt &&
269 		    attr.func_info_rec_size < load_attr->func_info_rec_size) {
270 			/* try with corrected func info records */
271 			finfo = alloc_zero_tailing_info(load_attr->func_info,
272 							load_attr->func_info_cnt,
273 							load_attr->func_info_rec_size,
274 							attr.func_info_rec_size);
275 			if (!finfo)
276 				goto done;
277 
278 			attr.func_info = ptr_to_u64(finfo);
279 			attr.func_info_rec_size = load_attr->func_info_rec_size;
280 		} else if (!linfo && attr.line_info_cnt &&
281 			   attr.line_info_rec_size <
282 			   load_attr->line_info_rec_size) {
283 			linfo = alloc_zero_tailing_info(load_attr->line_info,
284 							load_attr->line_info_cnt,
285 							load_attr->line_info_rec_size,
286 							attr.line_info_rec_size);
287 			if (!linfo)
288 				goto done;
289 
290 			attr.line_info = ptr_to_u64(linfo);
291 			attr.line_info_rec_size = load_attr->line_info_rec_size;
292 		} else {
293 			break;
294 		}
295 
296 		fd = sys_bpf_prog_load(&attr, sizeof(attr));
297 
298 		if (fd >= 0)
299 			goto done;
300 	}
301 
302 	if (log_level || !log_buf)
303 		goto done;
304 
305 	/* Try again with log */
306 	attr.log_buf = ptr_to_u64(log_buf);
307 	attr.log_size = log_buf_sz;
308 	attr.log_level = 1;
309 	log_buf[0] = 0;
310 	fd = sys_bpf_prog_load(&attr, sizeof(attr));
311 done:
312 	free(finfo);
313 	free(linfo);
314 	return fd;
315 }
316 
317 int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
318 		     size_t insns_cnt, const char *license,
319 		     __u32 kern_version, char *log_buf,
320 		     size_t log_buf_sz)
321 {
322 	struct bpf_load_program_attr load_attr;
323 
324 	memset(&load_attr, 0, sizeof(struct bpf_load_program_attr));
325 	load_attr.prog_type = type;
326 	load_attr.expected_attach_type = 0;
327 	load_attr.name = NULL;
328 	load_attr.insns = insns;
329 	load_attr.insns_cnt = insns_cnt;
330 	load_attr.license = license;
331 	load_attr.kern_version = kern_version;
332 
333 	return bpf_load_program_xattr(&load_attr, log_buf, log_buf_sz);
334 }
335 
336 int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
337 		       size_t insns_cnt, __u32 prog_flags, const char *license,
338 		       __u32 kern_version, char *log_buf, size_t log_buf_sz,
339 		       int log_level)
340 {
341 	union bpf_attr attr;
342 
343 	memset(&attr, 0, sizeof(attr));
344 	attr.prog_type = type;
345 	attr.insn_cnt = (__u32)insns_cnt;
346 	attr.insns = ptr_to_u64(insns);
347 	attr.license = ptr_to_u64(license);
348 	attr.log_buf = ptr_to_u64(log_buf);
349 	attr.log_size = log_buf_sz;
350 	attr.log_level = log_level;
351 	log_buf[0] = 0;
352 	attr.kern_version = kern_version;
353 	attr.prog_flags = prog_flags;
354 
355 	return sys_bpf_prog_load(&attr, sizeof(attr));
356 }
357 
358 int bpf_map_update_elem(int fd, const void *key, const void *value,
359 			__u64 flags)
360 {
361 	union bpf_attr attr;
362 
363 	memset(&attr, 0, sizeof(attr));
364 	attr.map_fd = fd;
365 	attr.key = ptr_to_u64(key);
366 	attr.value = ptr_to_u64(value);
367 	attr.flags = flags;
368 
369 	return sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
370 }
371 
372 int bpf_map_lookup_elem(int fd, const void *key, void *value)
373 {
374 	union bpf_attr attr;
375 
376 	memset(&attr, 0, sizeof(attr));
377 	attr.map_fd = fd;
378 	attr.key = ptr_to_u64(key);
379 	attr.value = ptr_to_u64(value);
380 
381 	return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
382 }
383 
384 int bpf_map_lookup_elem_flags(int fd, const void *key, void *value, __u64 flags)
385 {
386 	union bpf_attr attr;
387 
388 	memset(&attr, 0, sizeof(attr));
389 	attr.map_fd = fd;
390 	attr.key = ptr_to_u64(key);
391 	attr.value = ptr_to_u64(value);
392 	attr.flags = flags;
393 
394 	return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
395 }
396 
397 int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value)
398 {
399 	union bpf_attr attr;
400 
401 	memset(&attr, 0, sizeof(attr));
402 	attr.map_fd = fd;
403 	attr.key = ptr_to_u64(key);
404 	attr.value = ptr_to_u64(value);
405 
406 	return sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, sizeof(attr));
407 }
408 
409 int bpf_map_delete_elem(int fd, const void *key)
410 {
411 	union bpf_attr attr;
412 
413 	memset(&attr, 0, sizeof(attr));
414 	attr.map_fd = fd;
415 	attr.key = ptr_to_u64(key);
416 
417 	return sys_bpf(BPF_MAP_DELETE_ELEM, &attr, sizeof(attr));
418 }
419 
420 int bpf_map_get_next_key(int fd, const void *key, void *next_key)
421 {
422 	union bpf_attr attr;
423 
424 	memset(&attr, 0, sizeof(attr));
425 	attr.map_fd = fd;
426 	attr.key = ptr_to_u64(key);
427 	attr.next_key = ptr_to_u64(next_key);
428 
429 	return sys_bpf(BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr));
430 }
431 
432 int bpf_obj_pin(int fd, const char *pathname)
433 {
434 	union bpf_attr attr;
435 
436 	memset(&attr, 0, sizeof(attr));
437 	attr.pathname = ptr_to_u64((void *)pathname);
438 	attr.bpf_fd = fd;
439 
440 	return sys_bpf(BPF_OBJ_PIN, &attr, sizeof(attr));
441 }
442 
443 int bpf_obj_get(const char *pathname)
444 {
445 	union bpf_attr attr;
446 
447 	memset(&attr, 0, sizeof(attr));
448 	attr.pathname = ptr_to_u64((void *)pathname);
449 
450 	return sys_bpf(BPF_OBJ_GET, &attr, sizeof(attr));
451 }
452 
453 int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type,
454 		    unsigned int flags)
455 {
456 	union bpf_attr attr;
457 
458 	memset(&attr, 0, sizeof(attr));
459 	attr.target_fd	   = target_fd;
460 	attr.attach_bpf_fd = prog_fd;
461 	attr.attach_type   = type;
462 	attr.attach_flags  = flags;
463 
464 	return sys_bpf(BPF_PROG_ATTACH, &attr, sizeof(attr));
465 }
466 
467 int bpf_prog_detach(int target_fd, enum bpf_attach_type type)
468 {
469 	union bpf_attr attr;
470 
471 	memset(&attr, 0, sizeof(attr));
472 	attr.target_fd	 = target_fd;
473 	attr.attach_type = type;
474 
475 	return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
476 }
477 
478 int bpf_prog_detach2(int prog_fd, int target_fd, enum bpf_attach_type type)
479 {
480 	union bpf_attr attr;
481 
482 	memset(&attr, 0, sizeof(attr));
483 	attr.target_fd	 = target_fd;
484 	attr.attach_bpf_fd = prog_fd;
485 	attr.attach_type = type;
486 
487 	return sys_bpf(BPF_PROG_DETACH, &attr, sizeof(attr));
488 }
489 
490 int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags,
491 		   __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt)
492 {
493 	union bpf_attr attr;
494 	int ret;
495 
496 	memset(&attr, 0, sizeof(attr));
497 	attr.query.target_fd	= target_fd;
498 	attr.query.attach_type	= type;
499 	attr.query.query_flags	= query_flags;
500 	attr.query.prog_cnt	= *prog_cnt;
501 	attr.query.prog_ids	= ptr_to_u64(prog_ids);
502 
503 	ret = sys_bpf(BPF_PROG_QUERY, &attr, sizeof(attr));
504 	if (attach_flags)
505 		*attach_flags = attr.query.attach_flags;
506 	*prog_cnt = attr.query.prog_cnt;
507 	return ret;
508 }
509 
510 int bpf_prog_test_run(int prog_fd, int repeat, void *data, __u32 size,
511 		      void *data_out, __u32 *size_out, __u32 *retval,
512 		      __u32 *duration)
513 {
514 	union bpf_attr attr;
515 	int ret;
516 
517 	memset(&attr, 0, sizeof(attr));
518 	attr.test.prog_fd = prog_fd;
519 	attr.test.data_in = ptr_to_u64(data);
520 	attr.test.data_out = ptr_to_u64(data_out);
521 	attr.test.data_size_in = size;
522 	attr.test.repeat = repeat;
523 
524 	ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
525 	if (size_out)
526 		*size_out = attr.test.data_size_out;
527 	if (retval)
528 		*retval = attr.test.retval;
529 	if (duration)
530 		*duration = attr.test.duration;
531 	return ret;
532 }
533 
534 int bpf_prog_test_run_xattr(struct bpf_prog_test_run_attr *test_attr)
535 {
536 	union bpf_attr attr;
537 	int ret;
538 
539 	if (!test_attr->data_out && test_attr->data_size_out > 0)
540 		return -EINVAL;
541 
542 	memset(&attr, 0, sizeof(attr));
543 	attr.test.prog_fd = test_attr->prog_fd;
544 	attr.test.data_in = ptr_to_u64(test_attr->data_in);
545 	attr.test.data_out = ptr_to_u64(test_attr->data_out);
546 	attr.test.data_size_in = test_attr->data_size_in;
547 	attr.test.data_size_out = test_attr->data_size_out;
548 	attr.test.repeat = test_attr->repeat;
549 
550 	ret = sys_bpf(BPF_PROG_TEST_RUN, &attr, sizeof(attr));
551 	test_attr->data_size_out = attr.test.data_size_out;
552 	test_attr->retval = attr.test.retval;
553 	test_attr->duration = attr.test.duration;
554 	return ret;
555 }
556 
557 int bpf_prog_get_next_id(__u32 start_id, __u32 *next_id)
558 {
559 	union bpf_attr attr;
560 	int err;
561 
562 	memset(&attr, 0, sizeof(attr));
563 	attr.start_id = start_id;
564 
565 	err = sys_bpf(BPF_PROG_GET_NEXT_ID, &attr, sizeof(attr));
566 	if (!err)
567 		*next_id = attr.next_id;
568 
569 	return err;
570 }
571 
572 int bpf_map_get_next_id(__u32 start_id, __u32 *next_id)
573 {
574 	union bpf_attr attr;
575 	int err;
576 
577 	memset(&attr, 0, sizeof(attr));
578 	attr.start_id = start_id;
579 
580 	err = sys_bpf(BPF_MAP_GET_NEXT_ID, &attr, sizeof(attr));
581 	if (!err)
582 		*next_id = attr.next_id;
583 
584 	return err;
585 }
586 
587 int bpf_prog_get_fd_by_id(__u32 id)
588 {
589 	union bpf_attr attr;
590 
591 	memset(&attr, 0, sizeof(attr));
592 	attr.prog_id = id;
593 
594 	return sys_bpf(BPF_PROG_GET_FD_BY_ID, &attr, sizeof(attr));
595 }
596 
597 int bpf_map_get_fd_by_id(__u32 id)
598 {
599 	union bpf_attr attr;
600 
601 	memset(&attr, 0, sizeof(attr));
602 	attr.map_id = id;
603 
604 	return sys_bpf(BPF_MAP_GET_FD_BY_ID, &attr, sizeof(attr));
605 }
606 
607 int bpf_btf_get_fd_by_id(__u32 id)
608 {
609 	union bpf_attr attr;
610 
611 	memset(&attr, 0, sizeof(attr));
612 	attr.btf_id = id;
613 
614 	return sys_bpf(BPF_BTF_GET_FD_BY_ID, &attr, sizeof(attr));
615 }
616 
617 int bpf_obj_get_info_by_fd(int prog_fd, void *info, __u32 *info_len)
618 {
619 	union bpf_attr attr;
620 	int err;
621 
622 	memset(&attr, 0, sizeof(attr));
623 	attr.info.bpf_fd = prog_fd;
624 	attr.info.info_len = *info_len;
625 	attr.info.info = ptr_to_u64(info);
626 
627 	err = sys_bpf(BPF_OBJ_GET_INFO_BY_FD, &attr, sizeof(attr));
628 	if (!err)
629 		*info_len = attr.info.info_len;
630 
631 	return err;
632 }
633 
634 int bpf_raw_tracepoint_open(const char *name, int prog_fd)
635 {
636 	union bpf_attr attr;
637 
638 	memset(&attr, 0, sizeof(attr));
639 	attr.raw_tracepoint.name = ptr_to_u64(name);
640 	attr.raw_tracepoint.prog_fd = prog_fd;
641 
642 	return sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr));
643 }
644 
645 int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf, __u32 log_buf_size,
646 		 bool do_log)
647 {
648 	union bpf_attr attr = {};
649 	int fd;
650 
651 	attr.btf = ptr_to_u64(btf);
652 	attr.btf_size = btf_size;
653 
654 retry:
655 	if (do_log && log_buf && log_buf_size) {
656 		attr.btf_log_level = 1;
657 		attr.btf_log_size = log_buf_size;
658 		attr.btf_log_buf = ptr_to_u64(log_buf);
659 	}
660 
661 	fd = sys_bpf(BPF_BTF_LOAD, &attr, sizeof(attr));
662 	if (fd == -1 && !do_log && log_buf && log_buf_size) {
663 		do_log = true;
664 		goto retry;
665 	}
666 
667 	return fd;
668 }
669 
670 int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, __u32 *buf_len,
671 		      __u32 *prog_id, __u32 *fd_type, __u64 *probe_offset,
672 		      __u64 *probe_addr)
673 {
674 	union bpf_attr attr = {};
675 	int err;
676 
677 	attr.task_fd_query.pid = pid;
678 	attr.task_fd_query.fd = fd;
679 	attr.task_fd_query.flags = flags;
680 	attr.task_fd_query.buf = ptr_to_u64(buf);
681 	attr.task_fd_query.buf_len = *buf_len;
682 
683 	err = sys_bpf(BPF_TASK_FD_QUERY, &attr, sizeof(attr));
684 	*buf_len = attr.task_fd_query.buf_len;
685 	*prog_id = attr.task_fd_query.prog_id;
686 	*fd_type = attr.task_fd_query.fd_type;
687 	*probe_offset = attr.task_fd_query.probe_offset;
688 	*probe_addr = attr.task_fd_query.probe_addr;
689 
690 	return err;
691 }
692