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/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
/* libbpf has been moving quickly.
* They added new symbols in the 0.x versions and shortly after removed
* deprecated symbols in 1.0.
* We only need bpf_map_create and libbpf_probe_bpf_prog_type so we work
* around the incompatibility here by:
* - declaring both symbols, and looking for either depending on the libbpf
* so version we found
* - having helpers that automatically use the appropriate version behind the
* new API for easy cleanup later
*
* The advantage of doing this instead of only looking for the symbols declared at
* compile time is that we can then load either the old or the new symbols at runtime
* regardless of the version we were compiled with */
/* declare the struct for libbpf <= 0.6.0 -- it causes no harm on newer versions */
struct bpf_map_create_opts;
/* new symbols available from 0.7.0.
* We need the symbols here:
* - after bpf_map_create_opts struct has been defined for older libbpf
* - before the compat static inline helpers that use them.
* When removing this file move these back to bpf-dlopen.h */
extern int (*sym_bpf_map_create)(enum bpf_map_type, const char *, __u32, __u32, __u32, const struct bpf_map_create_opts *);
extern int (*sym_libbpf_probe_bpf_prog_type)(enum bpf_prog_type, const void *);
/* compat symbols removed in libbpf 1.0 */
extern int (*sym_bpf_create_map)(enum bpf_map_type, int key_size, int value_size, int max_entries, __u32 map_flags);
extern bool (*sym_bpf_probe_prog_type)(enum bpf_prog_type, __u32);
/* helpers to use the available variant behind new API */
static inline int compat_bpf_map_create(enum bpf_map_type map_type,
const char *map_name,
__u32 key_size,
__u32 value_size,
__u32 max_entries,
const struct bpf_map_create_opts *opts) {
if (sym_bpf_map_create)
return sym_bpf_map_create(map_type, map_name, key_size,
value_size, max_entries, opts);
return sym_bpf_create_map(map_type, key_size, value_size, max_entries,
0 /* opts->map_flags, but opts is always NULL for us so skip build dependency on the type */);
}
static inline int compat_libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts) {
if (sym_libbpf_probe_bpf_prog_type)
return sym_libbpf_probe_bpf_prog_type(prog_type, opts);
return sym_bpf_probe_prog_type(prog_type, 0);
}
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