1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ 2 3 /* 4 * Libbpf legacy APIs (either discouraged or deprecated, as mentioned in [0]) 5 * 6 * [0] https://docs.google.com/document/d/1UyjTZuPFWiPFyKk1tV5an11_iaRuec6U-ZESZ54nNTY 7 * 8 * Copyright (C) 2021 Facebook 9 */ 10 #ifndef __LIBBPF_LEGACY_BPF_H 11 #define __LIBBPF_LEGACY_BPF_H 12 13 #include <linux/bpf.h> 14 #include <stdbool.h> 15 #include <stddef.h> 16 #include <stdint.h> 17 #include "libbpf_common.h" 18 19 #ifdef __cplusplus 20 extern "C" { 21 #endif 22 23 /* As of libbpf 1.0 libbpf_set_strict_mode() and enum libbpf_struct_mode have 24 * no effect. But they are left in libbpf_legacy.h so that applications that 25 * prepared for libbpf 1.0 before final release by using 26 * libbpf_set_strict_mode() still work with libbpf 1.0+ without any changes. 27 */ 28 enum libbpf_strict_mode { 29 /* Turn on all supported strict features of libbpf to simulate libbpf 30 * v1.0 behavior. 31 * This will be the default behavior in libbpf v1.0. 32 */ 33 LIBBPF_STRICT_ALL = 0xffffffff, 34 35 /* 36 * Disable any libbpf 1.0 behaviors. This is the default before libbpf 37 * v1.0. It won't be supported anymore in v1.0, please update your 38 * code so that it handles LIBBPF_STRICT_ALL mode before libbpf v1.0. 39 */ 40 LIBBPF_STRICT_NONE = 0x00, 41 /* 42 * Return NULL pointers on error, not ERR_PTR(err). 43 * Additionally, libbpf also always sets errno to corresponding Exx 44 * (positive) error code. 45 */ 46 LIBBPF_STRICT_CLEAN_PTRS = 0x01, 47 /* 48 * Return actual error codes from low-level APIs directly, not just -1. 49 * Additionally, libbpf also always sets errno to corresponding Exx 50 * (positive) error code. 51 */ 52 LIBBPF_STRICT_DIRECT_ERRS = 0x02, 53 /* 54 * Enforce strict BPF program section (SEC()) names. 55 * E.g., while prefiously SEC("xdp_whatever") or SEC("perf_event_blah") were 56 * allowed, with LIBBPF_STRICT_SEC_PREFIX this will become 57 * unrecognized by libbpf and would have to be just SEC("xdp") and 58 * SEC("xdp") and SEC("perf_event"). 59 * 60 * Note, in this mode the program pin path will be based on the 61 * function name instead of section name. 62 * 63 * Additionally, routines in the .text section are always considered 64 * sub-programs. Legacy behavior allows for a single routine in .text 65 * to be a program. 66 */ 67 LIBBPF_STRICT_SEC_NAME = 0x04, 68 /* 69 * Disable the global 'bpf_objects_list'. Maintaining this list adds 70 * a race condition to bpf_object__open() and bpf_object__close(). 71 * Clients can maintain it on their own if it is valuable for them. 72 */ 73 LIBBPF_STRICT_NO_OBJECT_LIST = 0x08, 74 /* 75 * Automatically bump RLIMIT_MEMLOCK using setrlimit() before the 76 * first BPF program or map creation operation. This is done only if 77 * kernel is too old to support memcg-based memory accounting for BPF 78 * subsystem. By default, RLIMIT_MEMLOCK limit is set to RLIM_INFINITY, 79 * but it can be overriden with libbpf_set_memlock_rlim() API. 80 * Note that libbpf_set_memlock_rlim() needs to be called before 81 * the very first bpf_prog_load(), bpf_map_create() or bpf_object__load() 82 * operation. 83 */ 84 LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK = 0x10, 85 /* 86 * Error out on any SEC("maps") map definition, which are deprecated 87 * in favor of BTF-defined map definitions in SEC(".maps"). 88 */ 89 LIBBPF_STRICT_MAP_DEFINITIONS = 0x20, 90 91 __LIBBPF_STRICT_LAST, 92 }; 93 94 LIBBPF_API int libbpf_set_strict_mode(enum libbpf_strict_mode mode); 95 96 /** 97 * @brief **libbpf_get_error()** extracts the error code from the passed 98 * pointer 99 * @param ptr pointer returned from libbpf API function 100 * @return error code; or 0 if no error occured 101 * 102 * Note, as of libbpf 1.0 this function is not necessary and not recommended 103 * to be used. Libbpf doesn't return error code embedded into the pointer 104 * itself. Instead, NULL is returned on error and error code is passed through 105 * thread-local errno variable. **libbpf_get_error()** is just returning -errno 106 * value if it receives NULL, which is correct only if errno hasn't been 107 * modified between libbpf API call and corresponding **libbpf_get_error()** 108 * call. Prefer to check return for NULL and use errno directly. 109 * 110 * This API is left in libbpf 1.0 to allow applications that were 1.0-ready 111 * before final libbpf 1.0 without needing to change them. 112 */ 113 LIBBPF_API long libbpf_get_error(const void *ptr); 114 115 #define DECLARE_LIBBPF_OPTS LIBBPF_OPTS 116 117 /* "Discouraged" APIs which don't follow consistent libbpf naming patterns. 118 * They are normally a trivial aliases or wrappers for proper APIs and are 119 * left to minimize unnecessary disruption for users of libbpf. But they 120 * shouldn't be used going forward. 121 */ 122 123 struct bpf_program; 124 struct bpf_map; 125 struct btf; 126 struct btf_ext; 127 128 LIBBPF_API enum bpf_prog_type bpf_program__get_type(const struct bpf_program *prog); 129 LIBBPF_API enum bpf_attach_type bpf_program__get_expected_attach_type(const struct bpf_program *prog); 130 LIBBPF_API const char *bpf_map__get_pin_path(const struct bpf_map *map); 131 LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size); 132 LIBBPF_API const void *btf_ext__get_raw_data(const struct btf_ext *btf_ext, __u32 *size); 133 134 #ifdef __cplusplus 135 } /* extern "C" */ 136 #endif 137 138 #endif /* __LIBBPF_LEGACY_BPF_H */ 139