1 /* SPDX-License-Identifier: LGPL-2.1 */
4 * Common eBPF ELF object loading operations.
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.
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!)
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.
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>
23 #ifndef __BPF_LIBBPF_H
24 #define __BPF_LIBBPF_H
29 #include <sys/types.h> // for size_t
30 #include <linux/bpf.h>
33 __LIBBPF_ERRNO__START
= 4000,
35 /* Something wrong in libelf */
36 LIBBPF_ERRNO__LIBELF
= __LIBBPF_ERRNO__START
,
37 LIBBPF_ERRNO__FORMAT
, /* BPF object format invalid */
38 LIBBPF_ERRNO__KVERSION
, /* Incorrect or no 'version' section */
39 LIBBPF_ERRNO__ENDIAN
, /* Endian mismatch */
40 LIBBPF_ERRNO__INTERNAL
, /* Internal error in libbpf */
41 LIBBPF_ERRNO__RELOC
, /* Relocation failed */
42 LIBBPF_ERRNO__LOAD
, /* Load program failure for unknown reason */
43 LIBBPF_ERRNO__VERIFY
, /* Kernel verifier blocks program loading */
44 LIBBPF_ERRNO__PROG2BIG
, /* Program too big */
45 LIBBPF_ERRNO__KVER
, /* Incorrect kernel version */
46 LIBBPF_ERRNO__PROGTYPE
, /* Kernel doesn't support this program type */
47 LIBBPF_ERRNO__WRNGPID
, /* Wrong pid in netlink message */
48 LIBBPF_ERRNO__INVSEQ
, /* Invalid netlink sequence */
52 int libbpf_strerror(int err
, char *buf
, size_t size
);
55 * In include/linux/compiler-gcc.h, __printf is defined. However
56 * it should be better if libbpf.h doesn't depend on Linux header file.
57 * So instead of __printf, here we use gcc attribute directly.
59 typedef int (*libbpf_print_fn_t
)(const char *, ...)
60 __attribute__((format(printf
, 1, 2)));
62 void libbpf_set_print(libbpf_print_fn_t warn
,
63 libbpf_print_fn_t info
,
64 libbpf_print_fn_t debug
);
66 /* Hide internal to user */
69 struct bpf_object
*bpf_object__open(const char *path
);
70 struct bpf_object
*bpf_object__open_buffer(void *obj_buf
,
73 int bpf_object__pin(struct bpf_object
*object
, const char *path
);
74 void bpf_object__close(struct bpf_object
*object
);
76 /* Load/unload object into/from kernel */
77 int bpf_object__load(struct bpf_object
*obj
);
78 int bpf_object__unload(struct bpf_object
*obj
);
79 const char *bpf_object__name(struct bpf_object
*obj
);
80 unsigned int bpf_object__kversion(struct bpf_object
*obj
);
82 struct bpf_object
*bpf_object__next(struct bpf_object
*prev
);
83 #define bpf_object__for_each_safe(pos, tmp) \
84 for ((pos) = bpf_object__next(NULL), \
85 (tmp) = bpf_object__next(pos); \
87 (pos) = (tmp), (tmp) = bpf_object__next(tmp))
89 typedef void (*bpf_object_clear_priv_t
)(struct bpf_object
*, void *);
90 int bpf_object__set_priv(struct bpf_object
*obj
, void *priv
,
91 bpf_object_clear_priv_t clear_priv
);
92 void *bpf_object__priv(struct bpf_object
*prog
);
94 /* Accessors of bpf_program. */
96 struct bpf_program
*bpf_program__next(struct bpf_program
*prog
,
97 struct bpf_object
*obj
);
99 #define bpf_object__for_each_program(pos, obj) \
100 for ((pos) = bpf_program__next(NULL, (obj)); \
102 (pos) = bpf_program__next((pos), (obj)))
104 typedef void (*bpf_program_clear_priv_t
)(struct bpf_program
*,
107 int bpf_program__set_priv(struct bpf_program
*prog
, void *priv
,
108 bpf_program_clear_priv_t clear_priv
);
110 void *bpf_program__priv(struct bpf_program
*prog
);
112 const char *bpf_program__title(struct bpf_program
*prog
, bool needs_copy
);
114 int bpf_program__fd(struct bpf_program
*prog
);
115 int bpf_program__pin_instance(struct bpf_program
*prog
, const char *path
,
117 int bpf_program__pin(struct bpf_program
*prog
, const char *path
);
122 * Libbpf allows callers to adjust BPF programs before being loaded
123 * into kernel. One program in an object file can be transform into
124 * multiple variants to be attached to different code.
126 * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
127 * are APIs for this propose.
129 * - bpf_program_prep_t:
130 * It defines 'preprocessor', which is a caller defined function
131 * passed to libbpf through bpf_program__set_prep(), and will be
132 * called before program is loaded. The processor should adjust
133 * the program one time for each instances according to the number
136 * - bpf_program__set_prep:
137 * Attachs a preprocessor to a BPF program. The number of instances
138 * whould be created is also passed through this function.
140 * - bpf_program__nth_fd:
141 * After the program is loaded, get resuling fds from bpf program for
144 * If bpf_program__set_prep() is not used, the program whould be loaded
145 * without adjustment during bpf_object__load(). The program has only
146 * one instance. In this case bpf_program__fd(prog) is equal to
147 * bpf_program__nth_fd(prog, 0).
150 struct bpf_prog_prep_result
{
152 * If not NULL, load new instruction array.
153 * If set to NULL, don't load this instance.
155 struct bpf_insn
*new_insn_ptr
;
158 /* If not NULL, result fd is set to it */
163 * Parameters of bpf_program_prep_t:
164 * - prog: The bpf_program being loaded.
165 * - n: Index of instance being generated.
166 * - insns: BPF instructions array.
167 * - insns_cnt:Number of instructions in insns.
168 * - res: Output parameter, result of transformation.
171 * - Zero: pre-processing success.
172 * - Non-zero: pre-processing, stop loading.
174 typedef int (*bpf_program_prep_t
)(struct bpf_program
*prog
, int n
,
175 struct bpf_insn
*insns
, int insns_cnt
,
176 struct bpf_prog_prep_result
*res
);
178 int bpf_program__set_prep(struct bpf_program
*prog
, int nr_instance
,
179 bpf_program_prep_t prep
);
181 int bpf_program__nth_fd(struct bpf_program
*prog
, int n
);
184 * Adjust type of bpf program. Default is kprobe.
186 int bpf_program__set_socket_filter(struct bpf_program
*prog
);
187 int bpf_program__set_tracepoint(struct bpf_program
*prog
);
188 int bpf_program__set_kprobe(struct bpf_program
*prog
);
189 int bpf_program__set_sched_cls(struct bpf_program
*prog
);
190 int bpf_program__set_sched_act(struct bpf_program
*prog
);
191 int bpf_program__set_xdp(struct bpf_program
*prog
);
192 int bpf_program__set_perf_event(struct bpf_program
*prog
);
193 void bpf_program__set_type(struct bpf_program
*prog
, enum bpf_prog_type type
);
195 bool bpf_program__is_socket_filter(struct bpf_program
*prog
);
196 bool bpf_program__is_tracepoint(struct bpf_program
*prog
);
197 bool bpf_program__is_kprobe(struct bpf_program
*prog
);
198 bool bpf_program__is_sched_cls(struct bpf_program
*prog
);
199 bool bpf_program__is_sched_act(struct bpf_program
*prog
);
200 bool bpf_program__is_xdp(struct bpf_program
*prog
);
201 bool bpf_program__is_perf_event(struct bpf_program
*prog
);
204 * We don't need __attribute__((packed)) now since it is
205 * unnecessary for 'bpf_map_def' because they are all aligned.
206 * In addition, using it will trigger -Wpacked warning message,
207 * and will be treated as an error due to -Werror.
211 unsigned int key_size
;
212 unsigned int value_size
;
213 unsigned int max_entries
;
214 unsigned int map_flags
;
218 * There is another 'struct bpf_map' in include/linux/map.h. However,
219 * it is not a uapi header so no need to consider name clash.
223 bpf_object__find_map_by_name(struct bpf_object
*obj
, const char *name
);
226 * Get bpf_map through the offset of corresponding struct bpf_map_def
227 * in the bpf object file.
230 bpf_object__find_map_by_offset(struct bpf_object
*obj
, size_t offset
);
233 bpf_map__next(struct bpf_map
*map
, struct bpf_object
*obj
);
234 #define bpf_map__for_each(pos, obj) \
235 for ((pos) = bpf_map__next(NULL, (obj)); \
237 (pos) = bpf_map__next((pos), (obj)))
239 int bpf_map__fd(struct bpf_map
*map
);
240 const struct bpf_map_def
*bpf_map__def(struct bpf_map
*map
);
241 const char *bpf_map__name(struct bpf_map
*map
);
243 typedef void (*bpf_map_clear_priv_t
)(struct bpf_map
*, void *);
244 int bpf_map__set_priv(struct bpf_map
*map
, void *priv
,
245 bpf_map_clear_priv_t clear_priv
);
246 void *bpf_map__priv(struct bpf_map
*map
);
247 int bpf_map__pin(struct bpf_map
*map
, const char *path
);
249 long libbpf_get_error(const void *ptr
);
251 int bpf_prog_load(const char *file
, enum bpf_prog_type type
,
252 struct bpf_object
**pobj
, int *prog_fd
);
254 int bpf_set_link_xdp_fd(int ifindex
, int fd
, __u32 flags
);