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Diffstat (limited to 'tools/lib/bpf/libbpf_legacy.h')
| -rw-r--r-- | tools/lib/bpf/libbpf_legacy.h | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/tools/lib/bpf/libbpf_legacy.h b/tools/lib/bpf/libbpf_legacy.h new file mode 100644 index 000000000000..1e1be467bede --- /dev/null +++ b/tools/lib/bpf/libbpf_legacy.h @@ -0,0 +1,140 @@ +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ + +/* + * Libbpf legacy APIs (either discouraged or deprecated, as mentioned in [0]) + * + * [0] https://docs.google.com/document/d/1UyjTZuPFWiPFyKk1tV5an11_iaRuec6U-ZESZ54nNTY + * + * Copyright (C) 2021 Facebook + */ +#ifndef __LIBBPF_LEGACY_BPF_H +#define __LIBBPF_LEGACY_BPF_H + +#include <linux/bpf.h> +#include <stdbool.h> +#include <stddef.h> +#include <stdint.h> +#include "libbpf_common.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* As of libbpf 1.0 libbpf_set_strict_mode() and enum libbpf_struct_mode have + * no effect. But they are left in libbpf_legacy.h so that applications that + * prepared for libbpf 1.0 before final release by using + * libbpf_set_strict_mode() still work with libbpf 1.0+ without any changes. + */ +enum libbpf_strict_mode { + /* Turn on all supported strict features of libbpf to simulate libbpf + * v1.0 behavior. + * This will be the default behavior in libbpf v1.0. + */ + LIBBPF_STRICT_ALL = 0xffffffff, + + /* + * Disable any libbpf 1.0 behaviors. This is the default before libbpf + * v1.0. It won't be supported anymore in v1.0, please update your + * code so that it handles LIBBPF_STRICT_ALL mode before libbpf v1.0. + */ + LIBBPF_STRICT_NONE = 0x00, + /* + * Return NULL pointers on error, not ERR_PTR(err). + * Additionally, libbpf also always sets errno to corresponding Exx + * (positive) error code. + */ + LIBBPF_STRICT_CLEAN_PTRS = 0x01, + /* + * Return actual error codes from low-level APIs directly, not just -1. + * Additionally, libbpf also always sets errno to corresponding Exx + * (positive) error code. + */ + LIBBPF_STRICT_DIRECT_ERRS = 0x02, + /* + * Enforce strict BPF program section (SEC()) names. + * E.g., while prefiously SEC("xdp_whatever") or SEC("perf_event_blah") were + * allowed, with LIBBPF_STRICT_SEC_PREFIX this will become + * unrecognized by libbpf and would have to be just SEC("xdp") and + * SEC("xdp") and SEC("perf_event"). + * + * Note, in this mode the program pin path will be based on the + * function name instead of section name. + * + * Additionally, routines in the .text section are always considered + * sub-programs. Legacy behavior allows for a single routine in .text + * to be a program. + */ + LIBBPF_STRICT_SEC_NAME = 0x04, + /* + * Disable the global 'bpf_objects_list'. Maintaining this list adds + * a race condition to bpf_object__open() and bpf_object__close(). + * Clients can maintain it on their own if it is valuable for them. + */ + LIBBPF_STRICT_NO_OBJECT_LIST = 0x08, + /* + * Automatically bump RLIMIT_MEMLOCK using setrlimit() before the + * first BPF program or map creation operation. This is done only if + * kernel is too old to support memcg-based memory accounting for BPF + * subsystem. By default, RLIMIT_MEMLOCK limit is set to RLIM_INFINITY, + * but it can be overriden with libbpf_set_memlock_rlim() API. + * Note that libbpf_set_memlock_rlim() needs to be called before + * the very first bpf_prog_load(), bpf_map_create() or bpf_object__load() + * operation. + */ + LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK = 0x10, + /* + * Error out on any SEC("maps") map definition, which are deprecated + * in favor of BTF-defined map definitions in SEC(".maps"). + */ + LIBBPF_STRICT_MAP_DEFINITIONS = 0x20, + + __LIBBPF_STRICT_LAST, +}; + +LIBBPF_API int libbpf_set_strict_mode(enum libbpf_strict_mode mode); + +/** + * @brief **libbpf_get_error()** extracts the error code from the passed + * pointer + * @param ptr pointer returned from libbpf API function + * @return error code; or 0 if no error occured + * + * Note, as of libbpf 1.0 this function is not necessary and not recommended + * to be used. Libbpf doesn't return error code embedded into the pointer + * itself. Instead, NULL is returned on error and error code is passed through + * thread-local errno variable. **libbpf_get_error()** is just returning -errno + * value if it receives NULL, which is correct only if errno hasn't been + * modified between libbpf API call and corresponding **libbpf_get_error()** + * call. Prefer to check return for NULL and use errno directly. + * + * This API is left in libbpf 1.0 to allow applications that were 1.0-ready + * before final libbpf 1.0 without needing to change them. + */ +LIBBPF_API long libbpf_get_error(const void *ptr); + +#define DECLARE_LIBBPF_OPTS LIBBPF_OPTS + +/* "Discouraged" APIs which don't follow consistent libbpf naming patterns. + * They are normally a trivial aliases or wrappers for proper APIs and are + * left to minimize unnecessary disruption for users of libbpf. But they + * shouldn't be used going forward. + */ + +struct bpf_program; +struct bpf_map; +struct btf; +struct btf_ext; + +LIBBPF_API struct btf *libbpf_find_kernel_btf(void); + +LIBBPF_API enum bpf_prog_type bpf_program__get_type(const struct bpf_program *prog); +LIBBPF_API enum bpf_attach_type bpf_program__get_expected_attach_type(const struct bpf_program *prog); +LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map); +LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size); +LIBBPF_API const void *btf_ext__get_raw_data(const struct btf_ext *btf_ext, __u32 *size); + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* __LIBBPF_LEGACY_BPF_H */ |