1d7c4b398SAndrii Nakryiko /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ 2d7c4b398SAndrii Nakryiko 3d7c4b398SAndrii Nakryiko /* 4d7c4b398SAndrii Nakryiko * Internal libbpf helpers. 5d7c4b398SAndrii Nakryiko * 6d7c4b398SAndrii Nakryiko * Copyright (c) 2019 Facebook 7d7c4b398SAndrii Nakryiko */ 8d7c4b398SAndrii Nakryiko 9d7c4b398SAndrii Nakryiko #ifndef __LIBBPF_LIBBPF_INTERNAL_H 10d7c4b398SAndrii Nakryiko #define __LIBBPF_LIBBPF_INTERNAL_H 11d7c4b398SAndrii Nakryiko 121d7a08b3SAndrii Nakryiko #include "libbpf.h" 131d7a08b3SAndrii Nakryiko 14d7c4b398SAndrii Nakryiko #define BTF_INFO_ENC(kind, kind_flag, vlen) \ 15d7c4b398SAndrii Nakryiko ((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN)) 16d7c4b398SAndrii Nakryiko #define BTF_TYPE_ENC(name, info, size_or_type) (name), (info), (size_or_type) 17d7c4b398SAndrii Nakryiko #define BTF_INT_ENC(encoding, bits_offset, nr_bits) \ 18d7c4b398SAndrii Nakryiko ((encoding) << 24 | (bits_offset) << 16 | (nr_bits)) 19d7c4b398SAndrii Nakryiko #define BTF_TYPE_INT_ENC(name, encoding, bits_offset, bits, sz) \ 20d7c4b398SAndrii Nakryiko BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), sz), \ 21d7c4b398SAndrii Nakryiko BTF_INT_ENC(encoding, bits_offset, bits) 22d7c4b398SAndrii Nakryiko #define BTF_MEMBER_ENC(name, type, bits_offset) (name), (type), (bits_offset) 23d7c4b398SAndrii Nakryiko #define BTF_PARAM_ENC(name, type) (name), (type) 24d7c4b398SAndrii Nakryiko #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size) 25d7c4b398SAndrii Nakryiko 26d7fe74f9SAndrii Nakryiko #ifndef min 27d7fe74f9SAndrii Nakryiko # define min(x, y) ((x) < (y) ? (x) : (y)) 28d7fe74f9SAndrii Nakryiko #endif 29d7fe74f9SAndrii Nakryiko #ifndef max 30d7fe74f9SAndrii Nakryiko # define max(x, y) ((x) < (y) ? (y) : (x)) 31d7fe74f9SAndrii Nakryiko #endif 324cedc0daSAndrii Nakryiko #ifndef offsetofend 334cedc0daSAndrii Nakryiko # define offsetofend(TYPE, FIELD) \ 344cedc0daSAndrii Nakryiko (offsetof(TYPE, FIELD) + sizeof(((TYPE *)0)->FIELD)) 354cedc0daSAndrii Nakryiko #endif 36d7fe74f9SAndrii Nakryiko 371bd63524SYonghong Song /* Symbol versioning is different between static and shared library. 381bd63524SYonghong Song * Properly versioned symbols are needed for shared library, but 391bd63524SYonghong Song * only the symbol of the new version is needed for static library. 401bd63524SYonghong Song */ 411bd63524SYonghong Song #ifdef SHARED 421bd63524SYonghong Song # define COMPAT_VERSION(internal_name, api_name, version) \ 431bd63524SYonghong Song asm(".symver " #internal_name "," #api_name "@" #version); 441bd63524SYonghong Song # define DEFAULT_VERSION(internal_name, api_name, version) \ 451bd63524SYonghong Song asm(".symver " #internal_name "," #api_name "@@" #version); 461bd63524SYonghong Song #else 471bd63524SYonghong Song # define COMPAT_VERSION(internal_name, api_name, version) 481bd63524SYonghong Song # define DEFAULT_VERSION(internal_name, api_name, version) \ 491bd63524SYonghong Song extern typeof(internal_name) api_name \ 501bd63524SYonghong Song __attribute__((alias(#internal_name))); 511bd63524SYonghong Song #endif 521bd63524SYonghong Song 53d72386feSAndrii Nakryiko extern void libbpf_print(enum libbpf_print_level level, 54d72386feSAndrii Nakryiko const char *format, ...) 55d72386feSAndrii Nakryiko __attribute__((format(printf, 2, 3))); 56d72386feSAndrii Nakryiko 57d72386feSAndrii Nakryiko #define __pr(level, fmt, ...) \ 58d72386feSAndrii Nakryiko do { \ 59d72386feSAndrii Nakryiko libbpf_print(level, "libbpf: " fmt, ##__VA_ARGS__); \ 60d72386feSAndrii Nakryiko } while (0) 61d72386feSAndrii Nakryiko 62be18010eSKefeng Wang #define pr_warn(fmt, ...) __pr(LIBBPF_WARN, fmt, ##__VA_ARGS__) 63d72386feSAndrii Nakryiko #define pr_info(fmt, ...) __pr(LIBBPF_INFO, fmt, ##__VA_ARGS__) 64d72386feSAndrii Nakryiko #define pr_debug(fmt, ...) __pr(LIBBPF_DEBUG, fmt, ##__VA_ARGS__) 65d72386feSAndrii Nakryiko 662ce8450eSAndrii Nakryiko static inline bool libbpf_validate_opts(const char *opts, 672ce8450eSAndrii Nakryiko size_t opts_sz, size_t user_sz, 682ce8450eSAndrii Nakryiko const char *type_name) 692ce8450eSAndrii Nakryiko { 702ce8450eSAndrii Nakryiko if (user_sz < sizeof(size_t)) { 71be18010eSKefeng Wang pr_warn("%s size (%zu) is too small\n", type_name, user_sz); 722ce8450eSAndrii Nakryiko return false; 732ce8450eSAndrii Nakryiko } 742ce8450eSAndrii Nakryiko if (user_sz > opts_sz) { 752ce8450eSAndrii Nakryiko size_t i; 762ce8450eSAndrii Nakryiko 772ce8450eSAndrii Nakryiko for (i = opts_sz; i < user_sz; i++) { 782ce8450eSAndrii Nakryiko if (opts[i]) { 7912dd14b2SToke Høiland-Jørgensen pr_warn("%s has non-zero extra bytes\n", 802ce8450eSAndrii Nakryiko type_name); 812ce8450eSAndrii Nakryiko return false; 822ce8450eSAndrii Nakryiko } 832ce8450eSAndrii Nakryiko } 842ce8450eSAndrii Nakryiko } 852ce8450eSAndrii Nakryiko return true; 862ce8450eSAndrii Nakryiko } 872ce8450eSAndrii Nakryiko 882ce8450eSAndrii Nakryiko #define OPTS_VALID(opts, type) \ 892ce8450eSAndrii Nakryiko (!(opts) || libbpf_validate_opts((const char *)opts, \ 902ce8450eSAndrii Nakryiko offsetofend(struct type, \ 912ce8450eSAndrii Nakryiko type##__last_field), \ 922ce8450eSAndrii Nakryiko (opts)->sz, #type)) 932ce8450eSAndrii Nakryiko #define OPTS_HAS(opts, field) \ 942ce8450eSAndrii Nakryiko ((opts) && opts->sz >= offsetofend(typeof(*(opts)), field)) 952ce8450eSAndrii Nakryiko #define OPTS_GET(opts, field, fallback_value) \ 962ce8450eSAndrii Nakryiko (OPTS_HAS(opts, field) ? (opts)->field : fallback_value) 972ce8450eSAndrii Nakryiko 986803ee25SAndrii Nakryiko int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz); 996803ee25SAndrii Nakryiko int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz); 100cfd49210SMichal Rostecki int libbpf__load_raw_btf(const char *raw_types, size_t types_len, 101d7c4b398SAndrii Nakryiko const char *str_sec, size_t str_len); 102d7c4b398SAndrii Nakryiko 103612d05beSAndrii Nakryiko int bpf_object__section_size(const struct bpf_object *obj, const char *name, 104612d05beSAndrii Nakryiko __u32 *size); 105612d05beSAndrii Nakryiko int bpf_object__variable_offset(const struct bpf_object *obj, const char *name, 106612d05beSAndrii Nakryiko __u32 *off); 107612d05beSAndrii Nakryiko 108612d05beSAndrii Nakryiko struct nlattr; 109612d05beSAndrii Nakryiko typedef int (*libbpf_dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb); 110612d05beSAndrii Nakryiko int libbpf_netlink_open(unsigned int *nl_pid); 111612d05beSAndrii Nakryiko int libbpf_nl_get_link(int sock, unsigned int nl_pid, 112612d05beSAndrii Nakryiko libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie); 113612d05beSAndrii Nakryiko int libbpf_nl_get_class(int sock, unsigned int nl_pid, int ifindex, 114612d05beSAndrii Nakryiko libbpf_dump_nlmsg_t dump_class_nlmsg, void *cookie); 115612d05beSAndrii Nakryiko int libbpf_nl_get_qdisc(int sock, unsigned int nl_pid, int ifindex, 116612d05beSAndrii Nakryiko libbpf_dump_nlmsg_t dump_qdisc_nlmsg, void *cookie); 117612d05beSAndrii Nakryiko int libbpf_nl_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle, 118612d05beSAndrii Nakryiko libbpf_dump_nlmsg_t dump_filter_nlmsg, void *cookie); 119612d05beSAndrii Nakryiko 1204cedc0daSAndrii Nakryiko struct btf_ext_info { 1214cedc0daSAndrii Nakryiko /* 1224cedc0daSAndrii Nakryiko * info points to the individual info section (e.g. func_info and 1234cedc0daSAndrii Nakryiko * line_info) from the .BTF.ext. It does not include the __u32 rec_size. 1244cedc0daSAndrii Nakryiko */ 1254cedc0daSAndrii Nakryiko void *info; 1264cedc0daSAndrii Nakryiko __u32 rec_size; 1274cedc0daSAndrii Nakryiko __u32 len; 1284cedc0daSAndrii Nakryiko }; 1294cedc0daSAndrii Nakryiko 1304cedc0daSAndrii Nakryiko #define for_each_btf_ext_sec(seg, sec) \ 1314cedc0daSAndrii Nakryiko for (sec = (seg)->info; \ 1324cedc0daSAndrii Nakryiko (void *)sec < (seg)->info + (seg)->len; \ 1334cedc0daSAndrii Nakryiko sec = (void *)sec + sizeof(struct btf_ext_info_sec) + \ 1344cedc0daSAndrii Nakryiko (seg)->rec_size * sec->num_info) 1354cedc0daSAndrii Nakryiko 1364cedc0daSAndrii Nakryiko #define for_each_btf_ext_rec(seg, sec, i, rec) \ 1374cedc0daSAndrii Nakryiko for (i = 0, rec = (void *)&(sec)->data; \ 1384cedc0daSAndrii Nakryiko i < (sec)->num_info; \ 1394cedc0daSAndrii Nakryiko i++, rec = (void *)rec + (seg)->rec_size) 1404cedc0daSAndrii Nakryiko 1414cedc0daSAndrii Nakryiko struct btf_ext { 1424cedc0daSAndrii Nakryiko union { 1434cedc0daSAndrii Nakryiko struct btf_ext_header *hdr; 1444cedc0daSAndrii Nakryiko void *data; 1454cedc0daSAndrii Nakryiko }; 1464cedc0daSAndrii Nakryiko struct btf_ext_info func_info; 1474cedc0daSAndrii Nakryiko struct btf_ext_info line_info; 148511bb008SAndrii Nakryiko struct btf_ext_info field_reloc_info; 1494cedc0daSAndrii Nakryiko __u32 data_size; 1504cedc0daSAndrii Nakryiko }; 1514cedc0daSAndrii Nakryiko 1524cedc0daSAndrii Nakryiko struct btf_ext_info_sec { 1534cedc0daSAndrii Nakryiko __u32 sec_name_off; 1544cedc0daSAndrii Nakryiko __u32 num_info; 1554cedc0daSAndrii Nakryiko /* Followed by num_info * record_size number of bytes */ 1564cedc0daSAndrii Nakryiko __u8 data[0]; 1574cedc0daSAndrii Nakryiko }; 1584cedc0daSAndrii Nakryiko 1594cedc0daSAndrii Nakryiko /* The minimum bpf_func_info checked by the loader */ 1604cedc0daSAndrii Nakryiko struct bpf_func_info_min { 1614cedc0daSAndrii Nakryiko __u32 insn_off; 1624cedc0daSAndrii Nakryiko __u32 type_id; 1634cedc0daSAndrii Nakryiko }; 1644cedc0daSAndrii Nakryiko 1654cedc0daSAndrii Nakryiko /* The minimum bpf_line_info checked by the loader */ 1664cedc0daSAndrii Nakryiko struct bpf_line_info_min { 1674cedc0daSAndrii Nakryiko __u32 insn_off; 1684cedc0daSAndrii Nakryiko __u32 file_name_off; 1694cedc0daSAndrii Nakryiko __u32 line_off; 1704cedc0daSAndrii Nakryiko __u32 line_col; 1714cedc0daSAndrii Nakryiko }; 1724cedc0daSAndrii Nakryiko 173511bb008SAndrii Nakryiko /* bpf_field_info_kind encodes which aspect of captured field has to be 174511bb008SAndrii Nakryiko * adjusted by relocations. Currently supported values are: 175511bb008SAndrii Nakryiko * - BPF_FIELD_BYTE_OFFSET: field offset (in bytes); 176511bb008SAndrii Nakryiko * - BPF_FIELD_EXISTS: field existence (1, if field exists; 0, otherwise); 177511bb008SAndrii Nakryiko */ 178511bb008SAndrii Nakryiko enum bpf_field_info_kind { 179511bb008SAndrii Nakryiko BPF_FIELD_BYTE_OFFSET = 0, /* field byte offset */ 180ee26dadeSAndrii Nakryiko BPF_FIELD_BYTE_SIZE = 1, 181511bb008SAndrii Nakryiko BPF_FIELD_EXISTS = 2, /* field existence in target kernel */ 182ee26dadeSAndrii Nakryiko BPF_FIELD_SIGNED = 3, 183ee26dadeSAndrii Nakryiko BPF_FIELD_LSHIFT_U64 = 4, 184ee26dadeSAndrii Nakryiko BPF_FIELD_RSHIFT_U64 = 5, 185511bb008SAndrii Nakryiko }; 186511bb008SAndrii Nakryiko 187511bb008SAndrii Nakryiko /* The minimum bpf_field_reloc checked by the loader 1884cedc0daSAndrii Nakryiko * 189511bb008SAndrii Nakryiko * Field relocation captures the following data: 1904cedc0daSAndrii Nakryiko * - insn_off - instruction offset (in bytes) within a BPF program that needs 191511bb008SAndrii Nakryiko * its insn->imm field to be relocated with actual field info; 1924cedc0daSAndrii Nakryiko * - type_id - BTF type ID of the "root" (containing) entity of a relocatable 193511bb008SAndrii Nakryiko * field; 1944cedc0daSAndrii Nakryiko * - access_str_off - offset into corresponding .BTF string section. String 1954cedc0daSAndrii Nakryiko * itself encodes an accessed field using a sequence of field and array 1964cedc0daSAndrii Nakryiko * indicies, separated by colon (:). It's conceptually very close to LLVM's 1974cedc0daSAndrii Nakryiko * getelementptr ([0]) instruction's arguments for identifying offset to 1984cedc0daSAndrii Nakryiko * a field. 1994cedc0daSAndrii Nakryiko * 2004cedc0daSAndrii Nakryiko * Example to provide a better feel. 2014cedc0daSAndrii Nakryiko * 2024cedc0daSAndrii Nakryiko * struct sample { 2034cedc0daSAndrii Nakryiko * int a; 2044cedc0daSAndrii Nakryiko * struct { 2054cedc0daSAndrii Nakryiko * int b[10]; 2064cedc0daSAndrii Nakryiko * }; 2074cedc0daSAndrii Nakryiko * }; 2084cedc0daSAndrii Nakryiko * 2094cedc0daSAndrii Nakryiko * struct sample *s = ...; 2104cedc0daSAndrii Nakryiko * int x = &s->a; // encoded as "0:0" (a is field #0) 2114cedc0daSAndrii Nakryiko * int y = &s->b[5]; // encoded as "0:1:0:5" (anon struct is field #1, 2124cedc0daSAndrii Nakryiko * // b is field #0 inside anon struct, accessing elem #5) 2134cedc0daSAndrii Nakryiko * int z = &s[10]->b; // encoded as "10:1" (ptr is used as an array) 2144cedc0daSAndrii Nakryiko * 2154cedc0daSAndrii Nakryiko * type_id for all relocs in this example will capture BTF type id of 2164cedc0daSAndrii Nakryiko * `struct sample`. 2174cedc0daSAndrii Nakryiko * 2184cedc0daSAndrii Nakryiko * Such relocation is emitted when using __builtin_preserve_access_index() 2194cedc0daSAndrii Nakryiko * Clang built-in, passing expression that captures field address, e.g.: 2204cedc0daSAndrii Nakryiko * 2214cedc0daSAndrii Nakryiko * bpf_probe_read(&dst, sizeof(dst), 2224cedc0daSAndrii Nakryiko * __builtin_preserve_access_index(&src->a.b.c)); 2234cedc0daSAndrii Nakryiko * 224511bb008SAndrii Nakryiko * In this case Clang will emit field relocation recording necessary data to 2254cedc0daSAndrii Nakryiko * be able to find offset of embedded `a.b.c` field within `src` struct. 2264cedc0daSAndrii Nakryiko * 2274cedc0daSAndrii Nakryiko * [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction 2284cedc0daSAndrii Nakryiko */ 229511bb008SAndrii Nakryiko struct bpf_field_reloc { 2304cedc0daSAndrii Nakryiko __u32 insn_off; 2314cedc0daSAndrii Nakryiko __u32 type_id; 2324cedc0daSAndrii Nakryiko __u32 access_str_off; 233511bb008SAndrii Nakryiko enum bpf_field_info_kind kind; 2344cedc0daSAndrii Nakryiko }; 2354cedc0daSAndrii Nakryiko 236d7c4b398SAndrii Nakryiko #endif /* __LIBBPF_LIBBPF_INTERNAL_H */ 237