11bc38b8fSAlexei Starovoitov // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) 28a138aedSMartin KaFai Lau /* Copyright (c) 2018 Facebook */ 38a138aedSMartin KaFai Lau 43289959bSAndrii Nakryiko #include <byteswap.h> 5cdb2f920SArnaldo Carvalho de Melo #include <endian.h> 696408c43SYonghong Song #include <stdio.h> 78a138aedSMartin KaFai Lau #include <stdlib.h> 88a138aedSMartin KaFai Lau #include <string.h> 9e6c64855SAndrii Nakryiko #include <fcntl.h> 108a138aedSMartin KaFai Lau #include <unistd.h> 118a138aedSMartin KaFai Lau #include <errno.h> 12fb2426adSMartin KaFai Lau #include <sys/utsname.h> 13fb2426adSMartin KaFai Lau #include <sys/param.h> 14fb2426adSMartin KaFai Lau #include <sys/stat.h> 15fb2426adSMartin KaFai Lau #include <linux/kernel.h> 168a138aedSMartin KaFai Lau #include <linux/err.h> 178a138aedSMartin KaFai Lau #include <linux/btf.h> 18e6c64855SAndrii Nakryiko #include <gelf.h> 198a138aedSMartin KaFai Lau #include "btf.h" 208a138aedSMartin KaFai Lau #include "bpf.h" 218461ef8bSYonghong Song #include "libbpf.h" 22d72386feSAndrii Nakryiko #include "libbpf_internal.h" 232fc3fc0bSAndrii Nakryiko #include "hashmap.h" 2490d76d3eSAndrii Nakryiko #include "strset.h" 258a138aedSMartin KaFai Lau 26fb2426adSMartin KaFai Lau #define BTF_MAX_NR_TYPES 0x7fffffffU 27fb2426adSMartin KaFai Lau #define BTF_MAX_STR_OFFSET 0x7fffffffU 288a138aedSMartin KaFai Lau 298a138aedSMartin KaFai Lau static struct btf_type btf_void; 308a138aedSMartin KaFai Lau 318a138aedSMartin KaFai Lau struct btf { 323289959bSAndrii Nakryiko /* raw BTF data in native endianness */ 33b8604247SAndrii Nakryiko void *raw_data; 343289959bSAndrii Nakryiko /* raw BTF data in non-native endianness */ 353289959bSAndrii Nakryiko void *raw_data_swapped; 36b8604247SAndrii Nakryiko __u32 raw_size; 373289959bSAndrii Nakryiko /* whether target endianness differs from the native one */ 383289959bSAndrii Nakryiko bool swapped_endian; 39b8604247SAndrii Nakryiko 40b8604247SAndrii Nakryiko /* 419141f75aSAndrii Nakryiko * When BTF is loaded from an ELF or raw memory it is stored 429141f75aSAndrii Nakryiko * in a contiguous memory block. The hdr, type_data, and, strs_data 439141f75aSAndrii Nakryiko * point inside that memory region to their respective parts of BTF 449141f75aSAndrii Nakryiko * representation: 45b8604247SAndrii Nakryiko * 46b8604247SAndrii Nakryiko * +--------------------------------+ 47b8604247SAndrii Nakryiko * | Header | Types | Strings | 48b8604247SAndrii Nakryiko * +--------------------------------+ 49b8604247SAndrii Nakryiko * ^ ^ ^ 50b8604247SAndrii Nakryiko * | | | 51b8604247SAndrii Nakryiko * hdr | | 52b8604247SAndrii Nakryiko * types_data-+ | 53b8604247SAndrii Nakryiko * strs_data------------+ 54919d2b1dSAndrii Nakryiko * 55919d2b1dSAndrii Nakryiko * If BTF data is later modified, e.g., due to types added or 56919d2b1dSAndrii Nakryiko * removed, BTF deduplication performed, etc, this contiguous 57919d2b1dSAndrii Nakryiko * representation is broken up into three independently allocated 58919d2b1dSAndrii Nakryiko * memory regions to be able to modify them independently. 59919d2b1dSAndrii Nakryiko * raw_data is nulled out at that point, but can be later allocated 60919d2b1dSAndrii Nakryiko * and cached again if user calls btf__get_raw_data(), at which point 61919d2b1dSAndrii Nakryiko * raw_data will contain a contiguous copy of header, types, and 62919d2b1dSAndrii Nakryiko * strings: 63919d2b1dSAndrii Nakryiko * 64919d2b1dSAndrii Nakryiko * +----------+ +---------+ +-----------+ 65919d2b1dSAndrii Nakryiko * | Header | | Types | | Strings | 66919d2b1dSAndrii Nakryiko * +----------+ +---------+ +-----------+ 67919d2b1dSAndrii Nakryiko * ^ ^ ^ 68919d2b1dSAndrii Nakryiko * | | | 69919d2b1dSAndrii Nakryiko * hdr | | 70919d2b1dSAndrii Nakryiko * types_data----+ | 7190d76d3eSAndrii Nakryiko * strset__data(strs_set)-----+ 72919d2b1dSAndrii Nakryiko * 73919d2b1dSAndrii Nakryiko * +----------+---------+-----------+ 74919d2b1dSAndrii Nakryiko * | Header | Types | Strings | 75919d2b1dSAndrii Nakryiko * raw_data----->+----------+---------+-----------+ 76b8604247SAndrii Nakryiko */ 778a138aedSMartin KaFai Lau struct btf_header *hdr; 78919d2b1dSAndrii Nakryiko 79b8604247SAndrii Nakryiko void *types_data; 80919d2b1dSAndrii Nakryiko size_t types_data_cap; /* used size stored in hdr->type_len */ 81b8604247SAndrii Nakryiko 82ba451366SAndrii Nakryiko /* type ID to `struct btf_type *` lookup index 83ba451366SAndrii Nakryiko * type_offs[0] corresponds to the first non-VOID type: 84ba451366SAndrii Nakryiko * - for base BTF it's type [1]; 85ba451366SAndrii Nakryiko * - for split BTF it's the first non-base BTF type. 86ba451366SAndrii Nakryiko */ 87740e69c3SAndrii Nakryiko __u32 *type_offs; 88192f5a1fSAndrii Nakryiko size_t type_offs_cap; 89ba451366SAndrii Nakryiko /* number of types in this BTF instance: 90ba451366SAndrii Nakryiko * - doesn't include special [0] void type; 91ba451366SAndrii Nakryiko * - for split BTF counts number of types added on top of base BTF. 92ba451366SAndrii Nakryiko */ 935b891af7SMartin KaFai Lau __u32 nr_types; 94ba451366SAndrii Nakryiko /* if not NULL, points to the base BTF on top of which the current 95ba451366SAndrii Nakryiko * split BTF is based 96ba451366SAndrii Nakryiko */ 97ba451366SAndrii Nakryiko struct btf *base_btf; 98ba451366SAndrii Nakryiko /* BTF type ID of the first type in this BTF instance: 99ba451366SAndrii Nakryiko * - for base BTF it's equal to 1; 100ba451366SAndrii Nakryiko * - for split BTF it's equal to biggest type ID of base BTF plus 1. 101ba451366SAndrii Nakryiko */ 102ba451366SAndrii Nakryiko int start_id; 103ba451366SAndrii Nakryiko /* logical string offset of this BTF instance: 104ba451366SAndrii Nakryiko * - for base BTF it's equal to 0; 105ba451366SAndrii Nakryiko * - for split BTF it's equal to total size of base BTF's string section size. 106ba451366SAndrii Nakryiko */ 107ba451366SAndrii Nakryiko int start_str_off; 108b8604247SAndrii Nakryiko 10990d76d3eSAndrii Nakryiko /* only one of strs_data or strs_set can be non-NULL, depending on 11090d76d3eSAndrii Nakryiko * whether BTF is in a modifiable state (strs_set is used) or not 11190d76d3eSAndrii Nakryiko * (strs_data points inside raw_data) 11290d76d3eSAndrii Nakryiko */ 113919d2b1dSAndrii Nakryiko void *strs_data; 11490d76d3eSAndrii Nakryiko /* a set of unique strings */ 11590d76d3eSAndrii Nakryiko struct strset *strs_set; 116919d2b1dSAndrii Nakryiko /* whether strings are already deduplicated */ 117919d2b1dSAndrii Nakryiko bool strs_deduped; 11888a82c2aSAndrii Nakryiko 119b8604247SAndrii Nakryiko /* BTF object FD, if loaded into kernel */ 1208a138aedSMartin KaFai Lau int fd; 121b8604247SAndrii Nakryiko 122b8604247SAndrii Nakryiko /* Pointer size (in bytes) for a target architecture of this BTF */ 12344ad23dfSAndrii Nakryiko int ptr_sz; 1248a138aedSMartin KaFai Lau }; 1258a138aedSMartin KaFai Lau 126d7f5b5e0SYonghong Song static inline __u64 ptr_to_u64(const void *ptr) 127d7f5b5e0SYonghong Song { 128d7f5b5e0SYonghong Song return (__u64) (unsigned long) ptr; 129d7f5b5e0SYonghong Song } 130d7f5b5e0SYonghong Song 131192f5a1fSAndrii Nakryiko /* Ensure given dynamically allocated memory region pointed to by *data* with 132192f5a1fSAndrii Nakryiko * capacity of *cap_cnt* elements each taking *elem_sz* bytes has enough 133192f5a1fSAndrii Nakryiko * memory to accomodate *add_cnt* new elements, assuming *cur_cnt* elements 134192f5a1fSAndrii Nakryiko * are already used. At most *max_cnt* elements can be ever allocated. 135192f5a1fSAndrii Nakryiko * If necessary, memory is reallocated and all existing data is copied over, 136192f5a1fSAndrii Nakryiko * new pointer to the memory region is stored at *data, new memory region 137192f5a1fSAndrii Nakryiko * capacity (in number of elements) is stored in *cap. 138192f5a1fSAndrii Nakryiko * On success, memory pointer to the beginning of unused memory is returned. 139192f5a1fSAndrii Nakryiko * On error, NULL is returned. 140192f5a1fSAndrii Nakryiko */ 1413b029e06SAndrii Nakryiko void *libbpf_add_mem(void **data, size_t *cap_cnt, size_t elem_sz, 142192f5a1fSAndrii Nakryiko size_t cur_cnt, size_t max_cnt, size_t add_cnt) 1438a138aedSMartin KaFai Lau { 144192f5a1fSAndrii Nakryiko size_t new_cnt; 145192f5a1fSAndrii Nakryiko void *new_data; 1468a138aedSMartin KaFai Lau 147192f5a1fSAndrii Nakryiko if (cur_cnt + add_cnt <= *cap_cnt) 148192f5a1fSAndrii Nakryiko return *data + cur_cnt * elem_sz; 1498a138aedSMartin KaFai Lau 150192f5a1fSAndrii Nakryiko /* requested more than the set limit */ 151192f5a1fSAndrii Nakryiko if (cur_cnt + add_cnt > max_cnt) 152192f5a1fSAndrii Nakryiko return NULL; 1538a138aedSMartin KaFai Lau 154192f5a1fSAndrii Nakryiko new_cnt = *cap_cnt; 155192f5a1fSAndrii Nakryiko new_cnt += new_cnt / 4; /* expand by 25% */ 156192f5a1fSAndrii Nakryiko if (new_cnt < 16) /* but at least 16 elements */ 157192f5a1fSAndrii Nakryiko new_cnt = 16; 158192f5a1fSAndrii Nakryiko if (new_cnt > max_cnt) /* but not exceeding a set limit */ 159192f5a1fSAndrii Nakryiko new_cnt = max_cnt; 160192f5a1fSAndrii Nakryiko if (new_cnt < cur_cnt + add_cnt) /* also ensure we have enough memory */ 161192f5a1fSAndrii Nakryiko new_cnt = cur_cnt + add_cnt; 1628a138aedSMartin KaFai Lau 163192f5a1fSAndrii Nakryiko new_data = libbpf_reallocarray(*data, new_cnt, elem_sz); 164192f5a1fSAndrii Nakryiko if (!new_data) 165192f5a1fSAndrii Nakryiko return NULL; 1668a138aedSMartin KaFai Lau 167192f5a1fSAndrii Nakryiko /* zero out newly allocated portion of memory */ 168192f5a1fSAndrii Nakryiko memset(new_data + (*cap_cnt) * elem_sz, 0, (new_cnt - *cap_cnt) * elem_sz); 169192f5a1fSAndrii Nakryiko 170192f5a1fSAndrii Nakryiko *data = new_data; 171192f5a1fSAndrii Nakryiko *cap_cnt = new_cnt; 172192f5a1fSAndrii Nakryiko return new_data + cur_cnt * elem_sz; 1738a138aedSMartin KaFai Lau } 1748a138aedSMartin KaFai Lau 1759c6c5c48SAndrii Nakryiko /* Ensure given dynamically allocated memory region has enough allocated space 1769c6c5c48SAndrii Nakryiko * to accommodate *need_cnt* elements of size *elem_sz* bytes each 1779c6c5c48SAndrii Nakryiko */ 1783b029e06SAndrii Nakryiko int libbpf_ensure_mem(void **data, size_t *cap_cnt, size_t elem_sz, size_t need_cnt) 1799c6c5c48SAndrii Nakryiko { 1809c6c5c48SAndrii Nakryiko void *p; 1819c6c5c48SAndrii Nakryiko 1829c6c5c48SAndrii Nakryiko if (need_cnt <= *cap_cnt) 1839c6c5c48SAndrii Nakryiko return 0; 1849c6c5c48SAndrii Nakryiko 1853b029e06SAndrii Nakryiko p = libbpf_add_mem(data, cap_cnt, elem_sz, *cap_cnt, SIZE_MAX, need_cnt - *cap_cnt); 1869c6c5c48SAndrii Nakryiko if (!p) 1879c6c5c48SAndrii Nakryiko return -ENOMEM; 1889c6c5c48SAndrii Nakryiko 1899c6c5c48SAndrii Nakryiko return 0; 1909c6c5c48SAndrii Nakryiko } 1919c6c5c48SAndrii Nakryiko 1927ca61121SAndrii Nakryiko static void *btf_add_type_offs_mem(struct btf *btf, size_t add_cnt) 1937ca61121SAndrii Nakryiko { 1947ca61121SAndrii Nakryiko return libbpf_add_mem((void **)&btf->type_offs, &btf->type_offs_cap, sizeof(__u32), 1957ca61121SAndrii Nakryiko btf->nr_types, BTF_MAX_NR_TYPES, add_cnt); 1967ca61121SAndrii Nakryiko } 1977ca61121SAndrii Nakryiko 198192f5a1fSAndrii Nakryiko static int btf_add_type_idx_entry(struct btf *btf, __u32 type_off) 199192f5a1fSAndrii Nakryiko { 200192f5a1fSAndrii Nakryiko __u32 *p; 2018a138aedSMartin KaFai Lau 2027ca61121SAndrii Nakryiko p = btf_add_type_offs_mem(btf, 1); 203192f5a1fSAndrii Nakryiko if (!p) 204192f5a1fSAndrii Nakryiko return -ENOMEM; 205192f5a1fSAndrii Nakryiko 206192f5a1fSAndrii Nakryiko *p = type_off; 2078a138aedSMartin KaFai Lau return 0; 2088a138aedSMartin KaFai Lau } 2098a138aedSMartin KaFai Lau 2103289959bSAndrii Nakryiko static void btf_bswap_hdr(struct btf_header *h) 2113289959bSAndrii Nakryiko { 2123289959bSAndrii Nakryiko h->magic = bswap_16(h->magic); 2133289959bSAndrii Nakryiko h->hdr_len = bswap_32(h->hdr_len); 2143289959bSAndrii Nakryiko h->type_off = bswap_32(h->type_off); 2153289959bSAndrii Nakryiko h->type_len = bswap_32(h->type_len); 2163289959bSAndrii Nakryiko h->str_off = bswap_32(h->str_off); 2173289959bSAndrii Nakryiko h->str_len = bswap_32(h->str_len); 2183289959bSAndrii Nakryiko } 2193289959bSAndrii Nakryiko 2208461ef8bSYonghong Song static int btf_parse_hdr(struct btf *btf) 2218a138aedSMartin KaFai Lau { 2223289959bSAndrii Nakryiko struct btf_header *hdr = btf->hdr; 2235b891af7SMartin KaFai Lau __u32 meta_left; 2248a138aedSMartin KaFai Lau 225b8604247SAndrii Nakryiko if (btf->raw_size < sizeof(struct btf_header)) { 2268461ef8bSYonghong Song pr_debug("BTF header not found\n"); 2278a138aedSMartin KaFai Lau return -EINVAL; 2288a138aedSMartin KaFai Lau } 2298a138aedSMartin KaFai Lau 2303289959bSAndrii Nakryiko if (hdr->magic == bswap_16(BTF_MAGIC)) { 2313289959bSAndrii Nakryiko btf->swapped_endian = true; 2323289959bSAndrii Nakryiko if (bswap_32(hdr->hdr_len) != sizeof(struct btf_header)) { 2333289959bSAndrii Nakryiko pr_warn("Can't load BTF with non-native endianness due to unsupported header length %u\n", 2343289959bSAndrii Nakryiko bswap_32(hdr->hdr_len)); 2353289959bSAndrii Nakryiko return -ENOTSUP; 2363289959bSAndrii Nakryiko } 2373289959bSAndrii Nakryiko btf_bswap_hdr(hdr); 2383289959bSAndrii Nakryiko } else if (hdr->magic != BTF_MAGIC) { 2398461ef8bSYonghong Song pr_debug("Invalid BTF magic:%x\n", hdr->magic); 2408a138aedSMartin KaFai Lau return -EINVAL; 2418a138aedSMartin KaFai Lau } 2428a138aedSMartin KaFai Lau 243b8604247SAndrii Nakryiko meta_left = btf->raw_size - sizeof(*hdr); 244d8123624SAndrii Nakryiko if (meta_left < hdr->str_off + hdr->str_len) { 245d8123624SAndrii Nakryiko pr_debug("Invalid BTF total size:%u\n", btf->raw_size); 2468a138aedSMartin KaFai Lau return -EINVAL; 2478a138aedSMartin KaFai Lau } 2488a138aedSMartin KaFai Lau 249d8123624SAndrii Nakryiko if (hdr->type_off + hdr->type_len > hdr->str_off) { 250d8123624SAndrii Nakryiko pr_debug("Invalid BTF data sections layout: type data at %u + %u, strings data at %u + %u\n", 251d8123624SAndrii Nakryiko hdr->type_off, hdr->type_len, hdr->str_off, hdr->str_len); 2528a138aedSMartin KaFai Lau return -EINVAL; 2538a138aedSMartin KaFai Lau } 2548a138aedSMartin KaFai Lau 255d8123624SAndrii Nakryiko if (hdr->type_off % 4) { 2568461ef8bSYonghong Song pr_debug("BTF type section is not aligned to 4 bytes\n"); 2578a138aedSMartin KaFai Lau return -EINVAL; 2588a138aedSMartin KaFai Lau } 2598a138aedSMartin KaFai Lau 2608a138aedSMartin KaFai Lau return 0; 2618a138aedSMartin KaFai Lau } 2628a138aedSMartin KaFai Lau 2638461ef8bSYonghong Song static int btf_parse_str_sec(struct btf *btf) 2648a138aedSMartin KaFai Lau { 2658a138aedSMartin KaFai Lau const struct btf_header *hdr = btf->hdr; 266b8604247SAndrii Nakryiko const char *start = btf->strs_data; 2678a138aedSMartin KaFai Lau const char *end = start + btf->hdr->str_len; 2688a138aedSMartin KaFai Lau 269ba451366SAndrii Nakryiko if (btf->base_btf && hdr->str_len == 0) 270ba451366SAndrii Nakryiko return 0; 271ba451366SAndrii Nakryiko if (!hdr->str_len || hdr->str_len - 1 > BTF_MAX_STR_OFFSET || end[-1]) { 2728461ef8bSYonghong Song pr_debug("Invalid BTF string section\n"); 2738a138aedSMartin KaFai Lau return -EINVAL; 2748a138aedSMartin KaFai Lau } 275ba451366SAndrii Nakryiko if (!btf->base_btf && start[0]) { 276ba451366SAndrii Nakryiko pr_debug("Invalid BTF string section\n"); 277ba451366SAndrii Nakryiko return -EINVAL; 278ba451366SAndrii Nakryiko } 2798a138aedSMartin KaFai Lau return 0; 2808a138aedSMartin KaFai Lau } 2818a138aedSMartin KaFai Lau 282740e69c3SAndrii Nakryiko static int btf_type_size(const struct btf_type *t) 28369eaab04SAndrii Nakryiko { 2843289959bSAndrii Nakryiko const int base_size = sizeof(struct btf_type); 285b03bc685SAndrii Nakryiko __u16 vlen = btf_vlen(t); 28669eaab04SAndrii Nakryiko 287b03bc685SAndrii Nakryiko switch (btf_kind(t)) { 28869eaab04SAndrii Nakryiko case BTF_KIND_FWD: 28969eaab04SAndrii Nakryiko case BTF_KIND_CONST: 29069eaab04SAndrii Nakryiko case BTF_KIND_VOLATILE: 29169eaab04SAndrii Nakryiko case BTF_KIND_RESTRICT: 29269eaab04SAndrii Nakryiko case BTF_KIND_PTR: 29369eaab04SAndrii Nakryiko case BTF_KIND_TYPEDEF: 29469eaab04SAndrii Nakryiko case BTF_KIND_FUNC: 29522541a9eSIlya Leoshkevich case BTF_KIND_FLOAT: 29669eaab04SAndrii Nakryiko return base_size; 29769eaab04SAndrii Nakryiko case BTF_KIND_INT: 29869eaab04SAndrii Nakryiko return base_size + sizeof(__u32); 29969eaab04SAndrii Nakryiko case BTF_KIND_ENUM: 30069eaab04SAndrii Nakryiko return base_size + vlen * sizeof(struct btf_enum); 30169eaab04SAndrii Nakryiko case BTF_KIND_ARRAY: 30269eaab04SAndrii Nakryiko return base_size + sizeof(struct btf_array); 30369eaab04SAndrii Nakryiko case BTF_KIND_STRUCT: 30469eaab04SAndrii Nakryiko case BTF_KIND_UNION: 30569eaab04SAndrii Nakryiko return base_size + vlen * sizeof(struct btf_member); 30669eaab04SAndrii Nakryiko case BTF_KIND_FUNC_PROTO: 30769eaab04SAndrii Nakryiko return base_size + vlen * sizeof(struct btf_param); 3081713d68bSDaniel Borkmann case BTF_KIND_VAR: 3091713d68bSDaniel Borkmann return base_size + sizeof(struct btf_var); 3101713d68bSDaniel Borkmann case BTF_KIND_DATASEC: 3111713d68bSDaniel Borkmann return base_size + vlen * sizeof(struct btf_var_secinfo); 312223f903eSYonghong Song case BTF_KIND_DECL_TAG: 313223f903eSYonghong Song return base_size + sizeof(struct btf_decl_tag); 31469eaab04SAndrii Nakryiko default: 315b03bc685SAndrii Nakryiko pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t)); 31669eaab04SAndrii Nakryiko return -EINVAL; 31769eaab04SAndrii Nakryiko } 31869eaab04SAndrii Nakryiko } 31969eaab04SAndrii Nakryiko 3203289959bSAndrii Nakryiko static void btf_bswap_type_base(struct btf_type *t) 3213289959bSAndrii Nakryiko { 3223289959bSAndrii Nakryiko t->name_off = bswap_32(t->name_off); 3233289959bSAndrii Nakryiko t->info = bswap_32(t->info); 3243289959bSAndrii Nakryiko t->type = bswap_32(t->type); 3253289959bSAndrii Nakryiko } 3263289959bSAndrii Nakryiko 3273289959bSAndrii Nakryiko static int btf_bswap_type_rest(struct btf_type *t) 3283289959bSAndrii Nakryiko { 3293289959bSAndrii Nakryiko struct btf_var_secinfo *v; 3303289959bSAndrii Nakryiko struct btf_member *m; 3313289959bSAndrii Nakryiko struct btf_array *a; 3323289959bSAndrii Nakryiko struct btf_param *p; 3333289959bSAndrii Nakryiko struct btf_enum *e; 3343289959bSAndrii Nakryiko __u16 vlen = btf_vlen(t); 3353289959bSAndrii Nakryiko int i; 3363289959bSAndrii Nakryiko 3373289959bSAndrii Nakryiko switch (btf_kind(t)) { 3383289959bSAndrii Nakryiko case BTF_KIND_FWD: 3393289959bSAndrii Nakryiko case BTF_KIND_CONST: 3403289959bSAndrii Nakryiko case BTF_KIND_VOLATILE: 3413289959bSAndrii Nakryiko case BTF_KIND_RESTRICT: 3423289959bSAndrii Nakryiko case BTF_KIND_PTR: 3433289959bSAndrii Nakryiko case BTF_KIND_TYPEDEF: 3443289959bSAndrii Nakryiko case BTF_KIND_FUNC: 34522541a9eSIlya Leoshkevich case BTF_KIND_FLOAT: 3463289959bSAndrii Nakryiko return 0; 3473289959bSAndrii Nakryiko case BTF_KIND_INT: 3483289959bSAndrii Nakryiko *(__u32 *)(t + 1) = bswap_32(*(__u32 *)(t + 1)); 3493289959bSAndrii Nakryiko return 0; 3503289959bSAndrii Nakryiko case BTF_KIND_ENUM: 3513289959bSAndrii Nakryiko for (i = 0, e = btf_enum(t); i < vlen; i++, e++) { 3523289959bSAndrii Nakryiko e->name_off = bswap_32(e->name_off); 3533289959bSAndrii Nakryiko e->val = bswap_32(e->val); 3543289959bSAndrii Nakryiko } 3553289959bSAndrii Nakryiko return 0; 3563289959bSAndrii Nakryiko case BTF_KIND_ARRAY: 3573289959bSAndrii Nakryiko a = btf_array(t); 3583289959bSAndrii Nakryiko a->type = bswap_32(a->type); 3593289959bSAndrii Nakryiko a->index_type = bswap_32(a->index_type); 3603289959bSAndrii Nakryiko a->nelems = bswap_32(a->nelems); 3613289959bSAndrii Nakryiko return 0; 3623289959bSAndrii Nakryiko case BTF_KIND_STRUCT: 3633289959bSAndrii Nakryiko case BTF_KIND_UNION: 3643289959bSAndrii Nakryiko for (i = 0, m = btf_members(t); i < vlen; i++, m++) { 3653289959bSAndrii Nakryiko m->name_off = bswap_32(m->name_off); 3663289959bSAndrii Nakryiko m->type = bswap_32(m->type); 3673289959bSAndrii Nakryiko m->offset = bswap_32(m->offset); 3683289959bSAndrii Nakryiko } 3693289959bSAndrii Nakryiko return 0; 3703289959bSAndrii Nakryiko case BTF_KIND_FUNC_PROTO: 3713289959bSAndrii Nakryiko for (i = 0, p = btf_params(t); i < vlen; i++, p++) { 3723289959bSAndrii Nakryiko p->name_off = bswap_32(p->name_off); 3733289959bSAndrii Nakryiko p->type = bswap_32(p->type); 3743289959bSAndrii Nakryiko } 3753289959bSAndrii Nakryiko return 0; 3763289959bSAndrii Nakryiko case BTF_KIND_VAR: 3773289959bSAndrii Nakryiko btf_var(t)->linkage = bswap_32(btf_var(t)->linkage); 3783289959bSAndrii Nakryiko return 0; 3793289959bSAndrii Nakryiko case BTF_KIND_DATASEC: 3803289959bSAndrii Nakryiko for (i = 0, v = btf_var_secinfos(t); i < vlen; i++, v++) { 3813289959bSAndrii Nakryiko v->type = bswap_32(v->type); 3823289959bSAndrii Nakryiko v->offset = bswap_32(v->offset); 3833289959bSAndrii Nakryiko v->size = bswap_32(v->size); 3843289959bSAndrii Nakryiko } 3853289959bSAndrii Nakryiko return 0; 386223f903eSYonghong Song case BTF_KIND_DECL_TAG: 387223f903eSYonghong Song btf_decl_tag(t)->component_idx = bswap_32(btf_decl_tag(t)->component_idx); 3885b84bd10SYonghong Song return 0; 3893289959bSAndrii Nakryiko default: 3903289959bSAndrii Nakryiko pr_debug("Unsupported BTF_KIND:%u\n", btf_kind(t)); 3913289959bSAndrii Nakryiko return -EINVAL; 3923289959bSAndrii Nakryiko } 3933289959bSAndrii Nakryiko } 3943289959bSAndrii Nakryiko 3958461ef8bSYonghong Song static int btf_parse_type_sec(struct btf *btf) 3968a138aedSMartin KaFai Lau { 3978a138aedSMartin KaFai Lau struct btf_header *hdr = btf->hdr; 398b8604247SAndrii Nakryiko void *next_type = btf->types_data; 399740e69c3SAndrii Nakryiko void *end_type = next_type + hdr->type_len; 400ba451366SAndrii Nakryiko int err, type_size; 401740e69c3SAndrii Nakryiko 4023289959bSAndrii Nakryiko while (next_type + sizeof(struct btf_type) <= end_type) { 4033289959bSAndrii Nakryiko if (btf->swapped_endian) 4043289959bSAndrii Nakryiko btf_bswap_type_base(next_type); 405740e69c3SAndrii Nakryiko 406740e69c3SAndrii Nakryiko type_size = btf_type_size(next_type); 407740e69c3SAndrii Nakryiko if (type_size < 0) 408740e69c3SAndrii Nakryiko return type_size; 4093289959bSAndrii Nakryiko if (next_type + type_size > end_type) { 410ba451366SAndrii Nakryiko pr_warn("BTF type [%d] is malformed\n", btf->start_id + btf->nr_types); 4113289959bSAndrii Nakryiko return -EINVAL; 4123289959bSAndrii Nakryiko } 4133289959bSAndrii Nakryiko 4143289959bSAndrii Nakryiko if (btf->swapped_endian && btf_bswap_type_rest(next_type)) 4153289959bSAndrii Nakryiko return -EINVAL; 4163289959bSAndrii Nakryiko 4173289959bSAndrii Nakryiko err = btf_add_type_idx_entry(btf, next_type - btf->types_data); 4183289959bSAndrii Nakryiko if (err) 4193289959bSAndrii Nakryiko return err; 420740e69c3SAndrii Nakryiko 421740e69c3SAndrii Nakryiko next_type += type_size; 422740e69c3SAndrii Nakryiko btf->nr_types++; 4238a138aedSMartin KaFai Lau } 4248a138aedSMartin KaFai Lau 4253289959bSAndrii Nakryiko if (next_type != end_type) { 4263289959bSAndrii Nakryiko pr_warn("BTF types data is malformed\n"); 4273289959bSAndrii Nakryiko return -EINVAL; 4283289959bSAndrii Nakryiko } 4293289959bSAndrii Nakryiko 4308a138aedSMartin KaFai Lau return 0; 4318a138aedSMartin KaFai Lau } 4328a138aedSMartin KaFai Lau 4339c651127SAndrii Nakryiko __u32 btf__get_nr_types(const struct btf *btf) 4349c651127SAndrii Nakryiko { 435ba451366SAndrii Nakryiko return btf->start_id + btf->nr_types - 1; 4369c651127SAndrii Nakryiko } 4379c651127SAndrii Nakryiko 4380cfdcd63SAndrii Nakryiko const struct btf *btf__base_btf(const struct btf *btf) 4390cfdcd63SAndrii Nakryiko { 4400cfdcd63SAndrii Nakryiko return btf->base_btf; 4410cfdcd63SAndrii Nakryiko } 4420cfdcd63SAndrii Nakryiko 443740e69c3SAndrii Nakryiko /* internal helper returning non-const pointer to a type */ 444e14ef4bfSAndrii Nakryiko struct btf_type *btf_type_by_id(struct btf *btf, __u32 type_id) 445740e69c3SAndrii Nakryiko { 446740e69c3SAndrii Nakryiko if (type_id == 0) 447740e69c3SAndrii Nakryiko return &btf_void; 448ba451366SAndrii Nakryiko if (type_id < btf->start_id) 449ba451366SAndrii Nakryiko return btf_type_by_id(btf->base_btf, type_id); 450ba451366SAndrii Nakryiko return btf->types_data + btf->type_offs[type_id - btf->start_id]; 451740e69c3SAndrii Nakryiko } 452740e69c3SAndrii Nakryiko 45338d5d3b3SMartin KaFai Lau const struct btf_type *btf__type_by_id(const struct btf *btf, __u32 type_id) 4548a138aedSMartin KaFai Lau { 455ba451366SAndrii Nakryiko if (type_id >= btf->start_id + btf->nr_types) 456e9fc3ce9SAndrii Nakryiko return errno = EINVAL, NULL; 457740e69c3SAndrii Nakryiko return btf_type_by_id((struct btf *)btf, type_id); 4588a138aedSMartin KaFai Lau } 4598a138aedSMartin KaFai Lau 46044ad23dfSAndrii Nakryiko static int determine_ptr_size(const struct btf *btf) 46144ad23dfSAndrii Nakryiko { 46244ad23dfSAndrii Nakryiko const struct btf_type *t; 46344ad23dfSAndrii Nakryiko const char *name; 464ba451366SAndrii Nakryiko int i, n; 46544ad23dfSAndrii Nakryiko 466ba451366SAndrii Nakryiko if (btf->base_btf && btf->base_btf->ptr_sz > 0) 467ba451366SAndrii Nakryiko return btf->base_btf->ptr_sz; 468ba451366SAndrii Nakryiko 469ba451366SAndrii Nakryiko n = btf__get_nr_types(btf); 470ba451366SAndrii Nakryiko for (i = 1; i <= n; i++) { 47144ad23dfSAndrii Nakryiko t = btf__type_by_id(btf, i); 47244ad23dfSAndrii Nakryiko if (!btf_is_int(t)) 47344ad23dfSAndrii Nakryiko continue; 47444ad23dfSAndrii Nakryiko 47544ad23dfSAndrii Nakryiko name = btf__name_by_offset(btf, t->name_off); 47644ad23dfSAndrii Nakryiko if (!name) 47744ad23dfSAndrii Nakryiko continue; 47844ad23dfSAndrii Nakryiko 47944ad23dfSAndrii Nakryiko if (strcmp(name, "long int") == 0 || 48044ad23dfSAndrii Nakryiko strcmp(name, "long unsigned int") == 0) { 48144ad23dfSAndrii Nakryiko if (t->size != 4 && t->size != 8) 48244ad23dfSAndrii Nakryiko continue; 48344ad23dfSAndrii Nakryiko return t->size; 48444ad23dfSAndrii Nakryiko } 48544ad23dfSAndrii Nakryiko } 48644ad23dfSAndrii Nakryiko 48744ad23dfSAndrii Nakryiko return -1; 48844ad23dfSAndrii Nakryiko } 48944ad23dfSAndrii Nakryiko 49044ad23dfSAndrii Nakryiko static size_t btf_ptr_sz(const struct btf *btf) 49144ad23dfSAndrii Nakryiko { 49244ad23dfSAndrii Nakryiko if (!btf->ptr_sz) 49344ad23dfSAndrii Nakryiko ((struct btf *)btf)->ptr_sz = determine_ptr_size(btf); 49444ad23dfSAndrii Nakryiko return btf->ptr_sz < 0 ? sizeof(void *) : btf->ptr_sz; 49544ad23dfSAndrii Nakryiko } 49644ad23dfSAndrii Nakryiko 49744ad23dfSAndrii Nakryiko /* Return pointer size this BTF instance assumes. The size is heuristically 49844ad23dfSAndrii Nakryiko * determined by looking for 'long' or 'unsigned long' integer type and 49944ad23dfSAndrii Nakryiko * recording its size in bytes. If BTF type information doesn't have any such 50044ad23dfSAndrii Nakryiko * type, this function returns 0. In the latter case, native architecture's 50144ad23dfSAndrii Nakryiko * pointer size is assumed, so will be either 4 or 8, depending on 50244ad23dfSAndrii Nakryiko * architecture that libbpf was compiled for. It's possible to override 50344ad23dfSAndrii Nakryiko * guessed value by using btf__set_pointer_size() API. 50444ad23dfSAndrii Nakryiko */ 50544ad23dfSAndrii Nakryiko size_t btf__pointer_size(const struct btf *btf) 50644ad23dfSAndrii Nakryiko { 50744ad23dfSAndrii Nakryiko if (!btf->ptr_sz) 50844ad23dfSAndrii Nakryiko ((struct btf *)btf)->ptr_sz = determine_ptr_size(btf); 50944ad23dfSAndrii Nakryiko 51044ad23dfSAndrii Nakryiko if (btf->ptr_sz < 0) 51144ad23dfSAndrii Nakryiko /* not enough BTF type info to guess */ 51244ad23dfSAndrii Nakryiko return 0; 51344ad23dfSAndrii Nakryiko 51444ad23dfSAndrii Nakryiko return btf->ptr_sz; 51544ad23dfSAndrii Nakryiko } 51644ad23dfSAndrii Nakryiko 51744ad23dfSAndrii Nakryiko /* Override or set pointer size in bytes. Only values of 4 and 8 are 51844ad23dfSAndrii Nakryiko * supported. 51944ad23dfSAndrii Nakryiko */ 52044ad23dfSAndrii Nakryiko int btf__set_pointer_size(struct btf *btf, size_t ptr_sz) 52144ad23dfSAndrii Nakryiko { 52244ad23dfSAndrii Nakryiko if (ptr_sz != 4 && ptr_sz != 8) 523e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 52444ad23dfSAndrii Nakryiko btf->ptr_sz = ptr_sz; 52544ad23dfSAndrii Nakryiko return 0; 52644ad23dfSAndrii Nakryiko } 52744ad23dfSAndrii Nakryiko 5283289959bSAndrii Nakryiko static bool is_host_big_endian(void) 5293289959bSAndrii Nakryiko { 5303289959bSAndrii Nakryiko #if __BYTE_ORDER == __LITTLE_ENDIAN 5313289959bSAndrii Nakryiko return false; 5323289959bSAndrii Nakryiko #elif __BYTE_ORDER == __BIG_ENDIAN 5333289959bSAndrii Nakryiko return true; 5343289959bSAndrii Nakryiko #else 5353289959bSAndrii Nakryiko # error "Unrecognized __BYTE_ORDER__" 5363289959bSAndrii Nakryiko #endif 5373289959bSAndrii Nakryiko } 5383289959bSAndrii Nakryiko 5393289959bSAndrii Nakryiko enum btf_endianness btf__endianness(const struct btf *btf) 5403289959bSAndrii Nakryiko { 5413289959bSAndrii Nakryiko if (is_host_big_endian()) 5423289959bSAndrii Nakryiko return btf->swapped_endian ? BTF_LITTLE_ENDIAN : BTF_BIG_ENDIAN; 5433289959bSAndrii Nakryiko else 5443289959bSAndrii Nakryiko return btf->swapped_endian ? BTF_BIG_ENDIAN : BTF_LITTLE_ENDIAN; 5453289959bSAndrii Nakryiko } 5463289959bSAndrii Nakryiko 5473289959bSAndrii Nakryiko int btf__set_endianness(struct btf *btf, enum btf_endianness endian) 5483289959bSAndrii Nakryiko { 5493289959bSAndrii Nakryiko if (endian != BTF_LITTLE_ENDIAN && endian != BTF_BIG_ENDIAN) 550e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 5513289959bSAndrii Nakryiko 5523289959bSAndrii Nakryiko btf->swapped_endian = is_host_big_endian() != (endian == BTF_BIG_ENDIAN); 5533289959bSAndrii Nakryiko if (!btf->swapped_endian) { 5543289959bSAndrii Nakryiko free(btf->raw_data_swapped); 5553289959bSAndrii Nakryiko btf->raw_data_swapped = NULL; 5563289959bSAndrii Nakryiko } 5573289959bSAndrii Nakryiko return 0; 5583289959bSAndrii Nakryiko } 5593289959bSAndrii Nakryiko 5608a138aedSMartin KaFai Lau static bool btf_type_is_void(const struct btf_type *t) 5618a138aedSMartin KaFai Lau { 562b03bc685SAndrii Nakryiko return t == &btf_void || btf_is_fwd(t); 5638a138aedSMartin KaFai Lau } 5648a138aedSMartin KaFai Lau 5658a138aedSMartin KaFai Lau static bool btf_type_is_void_or_null(const struct btf_type *t) 5668a138aedSMartin KaFai Lau { 5678a138aedSMartin KaFai Lau return !t || btf_type_is_void(t); 5688a138aedSMartin KaFai Lau } 5698a138aedSMartin KaFai Lau 5708a138aedSMartin KaFai Lau #define MAX_RESOLVE_DEPTH 32 5718a138aedSMartin KaFai Lau 5725b891af7SMartin KaFai Lau __s64 btf__resolve_size(const struct btf *btf, __u32 type_id) 5738a138aedSMartin KaFai Lau { 5748a138aedSMartin KaFai Lau const struct btf_array *array; 5758a138aedSMartin KaFai Lau const struct btf_type *t; 5765b891af7SMartin KaFai Lau __u32 nelems = 1; 5775b891af7SMartin KaFai Lau __s64 size = -1; 5788a138aedSMartin KaFai Lau int i; 5798a138aedSMartin KaFai Lau 58092b57121SOkash Khawaja t = btf__type_by_id(btf, type_id); 581e9fc3ce9SAndrii Nakryiko for (i = 0; i < MAX_RESOLVE_DEPTH && !btf_type_is_void_or_null(t); i++) { 582b03bc685SAndrii Nakryiko switch (btf_kind(t)) { 58369eaab04SAndrii Nakryiko case BTF_KIND_INT: 58469eaab04SAndrii Nakryiko case BTF_KIND_STRUCT: 58569eaab04SAndrii Nakryiko case BTF_KIND_UNION: 58669eaab04SAndrii Nakryiko case BTF_KIND_ENUM: 5871713d68bSDaniel Borkmann case BTF_KIND_DATASEC: 58822541a9eSIlya Leoshkevich case BTF_KIND_FLOAT: 58969eaab04SAndrii Nakryiko size = t->size; 59069eaab04SAndrii Nakryiko goto done; 59169eaab04SAndrii Nakryiko case BTF_KIND_PTR: 59244ad23dfSAndrii Nakryiko size = btf_ptr_sz(btf); 59369eaab04SAndrii Nakryiko goto done; 5948a138aedSMartin KaFai Lau case BTF_KIND_TYPEDEF: 5958a138aedSMartin KaFai Lau case BTF_KIND_VOLATILE: 5968a138aedSMartin KaFai Lau case BTF_KIND_CONST: 5978a138aedSMartin KaFai Lau case BTF_KIND_RESTRICT: 5981713d68bSDaniel Borkmann case BTF_KIND_VAR: 599223f903eSYonghong Song case BTF_KIND_DECL_TAG: 6008a138aedSMartin KaFai Lau type_id = t->type; 6018a138aedSMartin KaFai Lau break; 6028a138aedSMartin KaFai Lau case BTF_KIND_ARRAY: 603b03bc685SAndrii Nakryiko array = btf_array(t); 6048a138aedSMartin KaFai Lau if (nelems && array->nelems > UINT32_MAX / nelems) 605e9fc3ce9SAndrii Nakryiko return libbpf_err(-E2BIG); 6068a138aedSMartin KaFai Lau nelems *= array->nelems; 6078a138aedSMartin KaFai Lau type_id = array->type; 6088a138aedSMartin KaFai Lau break; 6098a138aedSMartin KaFai Lau default: 610e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 6118a138aedSMartin KaFai Lau } 6128a138aedSMartin KaFai Lau 61392b57121SOkash Khawaja t = btf__type_by_id(btf, type_id); 6148a138aedSMartin KaFai Lau } 6158a138aedSMartin KaFai Lau 616994021a7SAndrii Nakryiko done: 6178a138aedSMartin KaFai Lau if (size < 0) 618e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 6198a138aedSMartin KaFai Lau if (nelems && size > UINT32_MAX / nelems) 620e9fc3ce9SAndrii Nakryiko return libbpf_err(-E2BIG); 6218a138aedSMartin KaFai Lau 6228a138aedSMartin KaFai Lau return nelems * size; 6238a138aedSMartin KaFai Lau } 6248a138aedSMartin KaFai Lau 6253d208f4cSAndrii Nakryiko int btf__align_of(const struct btf *btf, __u32 id) 6263d208f4cSAndrii Nakryiko { 6273d208f4cSAndrii Nakryiko const struct btf_type *t = btf__type_by_id(btf, id); 6283d208f4cSAndrii Nakryiko __u16 kind = btf_kind(t); 6293d208f4cSAndrii Nakryiko 6303d208f4cSAndrii Nakryiko switch (kind) { 6313d208f4cSAndrii Nakryiko case BTF_KIND_INT: 6323d208f4cSAndrii Nakryiko case BTF_KIND_ENUM: 63322541a9eSIlya Leoshkevich case BTF_KIND_FLOAT: 63444ad23dfSAndrii Nakryiko return min(btf_ptr_sz(btf), (size_t)t->size); 6353d208f4cSAndrii Nakryiko case BTF_KIND_PTR: 63644ad23dfSAndrii Nakryiko return btf_ptr_sz(btf); 6373d208f4cSAndrii Nakryiko case BTF_KIND_TYPEDEF: 6383d208f4cSAndrii Nakryiko case BTF_KIND_VOLATILE: 6393d208f4cSAndrii Nakryiko case BTF_KIND_CONST: 6403d208f4cSAndrii Nakryiko case BTF_KIND_RESTRICT: 6413d208f4cSAndrii Nakryiko return btf__align_of(btf, t->type); 6423d208f4cSAndrii Nakryiko case BTF_KIND_ARRAY: 6433d208f4cSAndrii Nakryiko return btf__align_of(btf, btf_array(t)->type); 6443d208f4cSAndrii Nakryiko case BTF_KIND_STRUCT: 6453d208f4cSAndrii Nakryiko case BTF_KIND_UNION: { 6463d208f4cSAndrii Nakryiko const struct btf_member *m = btf_members(t); 6473d208f4cSAndrii Nakryiko __u16 vlen = btf_vlen(t); 648a79ac2d1SPrashant Bhole int i, max_align = 1, align; 6493d208f4cSAndrii Nakryiko 6503d208f4cSAndrii Nakryiko for (i = 0; i < vlen; i++, m++) { 651a79ac2d1SPrashant Bhole align = btf__align_of(btf, m->type); 652a79ac2d1SPrashant Bhole if (align <= 0) 653e9fc3ce9SAndrii Nakryiko return libbpf_err(align); 654a79ac2d1SPrashant Bhole max_align = max(max_align, align); 6553d208f4cSAndrii Nakryiko } 6563d208f4cSAndrii Nakryiko 657a79ac2d1SPrashant Bhole return max_align; 6583d208f4cSAndrii Nakryiko } 6593d208f4cSAndrii Nakryiko default: 6603d208f4cSAndrii Nakryiko pr_warn("unsupported BTF_KIND:%u\n", btf_kind(t)); 661e9fc3ce9SAndrii Nakryiko return errno = EINVAL, 0; 6623d208f4cSAndrii Nakryiko } 6633d208f4cSAndrii Nakryiko } 6643d208f4cSAndrii Nakryiko 66592b57121SOkash Khawaja int btf__resolve_type(const struct btf *btf, __u32 type_id) 66692b57121SOkash Khawaja { 66792b57121SOkash Khawaja const struct btf_type *t; 66892b57121SOkash Khawaja int depth = 0; 66992b57121SOkash Khawaja 67092b57121SOkash Khawaja t = btf__type_by_id(btf, type_id); 67192b57121SOkash Khawaja while (depth < MAX_RESOLVE_DEPTH && 67292b57121SOkash Khawaja !btf_type_is_void_or_null(t) && 673b03bc685SAndrii Nakryiko (btf_is_mod(t) || btf_is_typedef(t) || btf_is_var(t))) { 67492b57121SOkash Khawaja type_id = t->type; 67592b57121SOkash Khawaja t = btf__type_by_id(btf, type_id); 67692b57121SOkash Khawaja depth++; 67792b57121SOkash Khawaja } 67892b57121SOkash Khawaja 67992b57121SOkash Khawaja if (depth == MAX_RESOLVE_DEPTH || btf_type_is_void_or_null(t)) 680e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 68192b57121SOkash Khawaja 68292b57121SOkash Khawaja return type_id; 68392b57121SOkash Khawaja } 68492b57121SOkash Khawaja 6855b891af7SMartin KaFai Lau __s32 btf__find_by_name(const struct btf *btf, const char *type_name) 6868a138aedSMartin KaFai Lau { 687de91e631SAlan Maguire __u32 i, nr_types = btf__get_nr_types(btf); 6888a138aedSMartin KaFai Lau 6898a138aedSMartin KaFai Lau if (!strcmp(type_name, "void")) 6908a138aedSMartin KaFai Lau return 0; 6918a138aedSMartin KaFai Lau 692de91e631SAlan Maguire for (i = 1; i <= nr_types; i++) { 693740e69c3SAndrii Nakryiko const struct btf_type *t = btf__type_by_id(btf, i); 69492b57121SOkash Khawaja const char *name = btf__name_by_offset(btf, t->name_off); 6958a138aedSMartin KaFai Lau 6968a138aedSMartin KaFai Lau if (name && !strcmp(type_name, name)) 6978a138aedSMartin KaFai Lau return i; 6988a138aedSMartin KaFai Lau } 6998a138aedSMartin KaFai Lau 700e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOENT); 7018a138aedSMartin KaFai Lau } 7028a138aedSMartin KaFai Lau 7039dbe6015SKumar Kartikeya Dwivedi static __s32 btf_find_by_name_kind(const struct btf *btf, int start_id, 7049dbe6015SKumar Kartikeya Dwivedi const char *type_name, __u32 kind) 7051442e287SAlexei Starovoitov { 706de91e631SAlan Maguire __u32 i, nr_types = btf__get_nr_types(btf); 7071442e287SAlexei Starovoitov 7081442e287SAlexei Starovoitov if (kind == BTF_KIND_UNKN || !strcmp(type_name, "void")) 7091442e287SAlexei Starovoitov return 0; 7101442e287SAlexei Starovoitov 7119dbe6015SKumar Kartikeya Dwivedi for (i = start_id; i <= nr_types; i++) { 712740e69c3SAndrii Nakryiko const struct btf_type *t = btf__type_by_id(btf, i); 7131442e287SAlexei Starovoitov const char *name; 7141442e287SAlexei Starovoitov 7151442e287SAlexei Starovoitov if (btf_kind(t) != kind) 7161442e287SAlexei Starovoitov continue; 7171442e287SAlexei Starovoitov name = btf__name_by_offset(btf, t->name_off); 7181442e287SAlexei Starovoitov if (name && !strcmp(type_name, name)) 7191442e287SAlexei Starovoitov return i; 7201442e287SAlexei Starovoitov } 7211442e287SAlexei Starovoitov 722e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOENT); 7231442e287SAlexei Starovoitov } 7241442e287SAlexei Starovoitov 7259dbe6015SKumar Kartikeya Dwivedi __s32 btf__find_by_name_kind_own(const struct btf *btf, const char *type_name, 7269dbe6015SKumar Kartikeya Dwivedi __u32 kind) 7279dbe6015SKumar Kartikeya Dwivedi { 7289dbe6015SKumar Kartikeya Dwivedi return btf_find_by_name_kind(btf, btf->start_id, type_name, kind); 7299dbe6015SKumar Kartikeya Dwivedi } 7309dbe6015SKumar Kartikeya Dwivedi 7319dbe6015SKumar Kartikeya Dwivedi __s32 btf__find_by_name_kind(const struct btf *btf, const char *type_name, 7329dbe6015SKumar Kartikeya Dwivedi __u32 kind) 7339dbe6015SKumar Kartikeya Dwivedi { 7349dbe6015SKumar Kartikeya Dwivedi return btf_find_by_name_kind(btf, 1, type_name, kind); 7359dbe6015SKumar Kartikeya Dwivedi } 7369dbe6015SKumar Kartikeya Dwivedi 737919d2b1dSAndrii Nakryiko static bool btf_is_modifiable(const struct btf *btf) 738919d2b1dSAndrii Nakryiko { 739919d2b1dSAndrii Nakryiko return (void *)btf->hdr != btf->raw_data; 740919d2b1dSAndrii Nakryiko } 741919d2b1dSAndrii Nakryiko 7428a138aedSMartin KaFai Lau void btf__free(struct btf *btf) 7438a138aedSMartin KaFai Lau { 74450450fc7SAndrii Nakryiko if (IS_ERR_OR_NULL(btf)) 7458a138aedSMartin KaFai Lau return; 7468a138aedSMartin KaFai Lau 74781372e12SAndrii Nakryiko if (btf->fd >= 0) 7488a138aedSMartin KaFai Lau close(btf->fd); 7498a138aedSMartin KaFai Lau 750919d2b1dSAndrii Nakryiko if (btf_is_modifiable(btf)) { 751919d2b1dSAndrii Nakryiko /* if BTF was modified after loading, it will have a split 752919d2b1dSAndrii Nakryiko * in-memory representation for header, types, and strings 753919d2b1dSAndrii Nakryiko * sections, so we need to free all of them individually. It 754919d2b1dSAndrii Nakryiko * might still have a cached contiguous raw data present, 755919d2b1dSAndrii Nakryiko * which will be unconditionally freed below. 756919d2b1dSAndrii Nakryiko */ 757919d2b1dSAndrii Nakryiko free(btf->hdr); 758919d2b1dSAndrii Nakryiko free(btf->types_data); 75990d76d3eSAndrii Nakryiko strset__free(btf->strs_set); 760919d2b1dSAndrii Nakryiko } 761b8604247SAndrii Nakryiko free(btf->raw_data); 7623289959bSAndrii Nakryiko free(btf->raw_data_swapped); 763740e69c3SAndrii Nakryiko free(btf->type_offs); 7648a138aedSMartin KaFai Lau free(btf); 7658a138aedSMartin KaFai Lau } 7668a138aedSMartin KaFai Lau 767ba451366SAndrii Nakryiko static struct btf *btf_new_empty(struct btf *base_btf) 768a871b043SAndrii Nakryiko { 769a871b043SAndrii Nakryiko struct btf *btf; 770a871b043SAndrii Nakryiko 771a871b043SAndrii Nakryiko btf = calloc(1, sizeof(*btf)); 772a871b043SAndrii Nakryiko if (!btf) 773a871b043SAndrii Nakryiko return ERR_PTR(-ENOMEM); 7743289959bSAndrii Nakryiko 775ba451366SAndrii Nakryiko btf->nr_types = 0; 776ba451366SAndrii Nakryiko btf->start_id = 1; 777ba451366SAndrii Nakryiko btf->start_str_off = 0; 778a871b043SAndrii Nakryiko btf->fd = -1; 779a871b043SAndrii Nakryiko btf->ptr_sz = sizeof(void *); 7803289959bSAndrii Nakryiko btf->swapped_endian = false; 781a871b043SAndrii Nakryiko 782ba451366SAndrii Nakryiko if (base_btf) { 783ba451366SAndrii Nakryiko btf->base_btf = base_btf; 784ba451366SAndrii Nakryiko btf->start_id = btf__get_nr_types(base_btf) + 1; 785ba451366SAndrii Nakryiko btf->start_str_off = base_btf->hdr->str_len; 786ba451366SAndrii Nakryiko } 787ba451366SAndrii Nakryiko 788a871b043SAndrii Nakryiko /* +1 for empty string at offset 0 */ 789ba451366SAndrii Nakryiko btf->raw_size = sizeof(struct btf_header) + (base_btf ? 0 : 1); 790a871b043SAndrii Nakryiko btf->raw_data = calloc(1, btf->raw_size); 791a871b043SAndrii Nakryiko if (!btf->raw_data) { 792a871b043SAndrii Nakryiko free(btf); 793a871b043SAndrii Nakryiko return ERR_PTR(-ENOMEM); 794a871b043SAndrii Nakryiko } 795a871b043SAndrii Nakryiko 796a871b043SAndrii Nakryiko btf->hdr = btf->raw_data; 797a871b043SAndrii Nakryiko btf->hdr->hdr_len = sizeof(struct btf_header); 798a871b043SAndrii Nakryiko btf->hdr->magic = BTF_MAGIC; 799a871b043SAndrii Nakryiko btf->hdr->version = BTF_VERSION; 800a871b043SAndrii Nakryiko 801a871b043SAndrii Nakryiko btf->types_data = btf->raw_data + btf->hdr->hdr_len; 802a871b043SAndrii Nakryiko btf->strs_data = btf->raw_data + btf->hdr->hdr_len; 803ba451366SAndrii Nakryiko btf->hdr->str_len = base_btf ? 0 : 1; /* empty string at offset 0 */ 804a871b043SAndrii Nakryiko 805a871b043SAndrii Nakryiko return btf; 806a871b043SAndrii Nakryiko } 807a871b043SAndrii Nakryiko 808ba451366SAndrii Nakryiko struct btf *btf__new_empty(void) 809ba451366SAndrii Nakryiko { 810e9fc3ce9SAndrii Nakryiko return libbpf_ptr(btf_new_empty(NULL)); 811ba451366SAndrii Nakryiko } 812ba451366SAndrii Nakryiko 813ba451366SAndrii Nakryiko struct btf *btf__new_empty_split(struct btf *base_btf) 814ba451366SAndrii Nakryiko { 815e9fc3ce9SAndrii Nakryiko return libbpf_ptr(btf_new_empty(base_btf)); 816ba451366SAndrii Nakryiko } 817ba451366SAndrii Nakryiko 818ba451366SAndrii Nakryiko static struct btf *btf_new(const void *data, __u32 size, struct btf *base_btf) 8198a138aedSMartin KaFai Lau { 8208a138aedSMartin KaFai Lau struct btf *btf; 8218a138aedSMartin KaFai Lau int err; 8228a138aedSMartin KaFai Lau 8238a138aedSMartin KaFai Lau btf = calloc(1, sizeof(struct btf)); 8248a138aedSMartin KaFai Lau if (!btf) 8258a138aedSMartin KaFai Lau return ERR_PTR(-ENOMEM); 8268a138aedSMartin KaFai Lau 827ba451366SAndrii Nakryiko btf->nr_types = 0; 828ba451366SAndrii Nakryiko btf->start_id = 1; 829ba451366SAndrii Nakryiko btf->start_str_off = 0; 830c34c338aSDaniel Xu btf->fd = -1; 831ba451366SAndrii Nakryiko 832ba451366SAndrii Nakryiko if (base_btf) { 833ba451366SAndrii Nakryiko btf->base_btf = base_btf; 834ba451366SAndrii Nakryiko btf->start_id = btf__get_nr_types(base_btf) + 1; 835ba451366SAndrii Nakryiko btf->start_str_off = base_btf->hdr->str_len; 836ba451366SAndrii Nakryiko } 837ba451366SAndrii Nakryiko 838b8604247SAndrii Nakryiko btf->raw_data = malloc(size); 839b8604247SAndrii Nakryiko if (!btf->raw_data) { 8408a138aedSMartin KaFai Lau err = -ENOMEM; 8418a138aedSMartin KaFai Lau goto done; 8428a138aedSMartin KaFai Lau } 843b8604247SAndrii Nakryiko memcpy(btf->raw_data, data, size); 844b8604247SAndrii Nakryiko btf->raw_size = size; 8458a138aedSMartin KaFai Lau 846b8604247SAndrii Nakryiko btf->hdr = btf->raw_data; 8478461ef8bSYonghong Song err = btf_parse_hdr(btf); 8488a138aedSMartin KaFai Lau if (err) 8498a138aedSMartin KaFai Lau goto done; 8508a138aedSMartin KaFai Lau 851b8604247SAndrii Nakryiko btf->strs_data = btf->raw_data + btf->hdr->hdr_len + btf->hdr->str_off; 852b8604247SAndrii Nakryiko btf->types_data = btf->raw_data + btf->hdr->hdr_len + btf->hdr->type_off; 8538a138aedSMartin KaFai Lau 854b8604247SAndrii Nakryiko err = btf_parse_str_sec(btf); 855b8604247SAndrii Nakryiko err = err ?: btf_parse_type_sec(btf); 8563289959bSAndrii Nakryiko if (err) 8573289959bSAndrii Nakryiko goto done; 8583289959bSAndrii Nakryiko 8598a138aedSMartin KaFai Lau done: 8608a138aedSMartin KaFai Lau if (err) { 8618a138aedSMartin KaFai Lau btf__free(btf); 8628a138aedSMartin KaFai Lau return ERR_PTR(err); 8638a138aedSMartin KaFai Lau } 8648a138aedSMartin KaFai Lau 8658a138aedSMartin KaFai Lau return btf; 8668a138aedSMartin KaFai Lau } 8678a138aedSMartin KaFai Lau 868ba451366SAndrii Nakryiko struct btf *btf__new(const void *data, __u32 size) 869ba451366SAndrii Nakryiko { 870e9fc3ce9SAndrii Nakryiko return libbpf_ptr(btf_new(data, size, NULL)); 871ba451366SAndrii Nakryiko } 872ba451366SAndrii Nakryiko 873ba451366SAndrii Nakryiko static struct btf *btf_parse_elf(const char *path, struct btf *base_btf, 874ba451366SAndrii Nakryiko struct btf_ext **btf_ext) 875e6c64855SAndrii Nakryiko { 876e6c64855SAndrii Nakryiko Elf_Data *btf_data = NULL, *btf_ext_data = NULL; 877e6c64855SAndrii Nakryiko int err = 0, fd = -1, idx = 0; 878e6c64855SAndrii Nakryiko struct btf *btf = NULL; 879e6c64855SAndrii Nakryiko Elf_Scn *scn = NULL; 880e6c64855SAndrii Nakryiko Elf *elf = NULL; 881e6c64855SAndrii Nakryiko GElf_Ehdr ehdr; 8826095d5a2SJiri Olsa size_t shstrndx; 883e6c64855SAndrii Nakryiko 884e6c64855SAndrii Nakryiko if (elf_version(EV_CURRENT) == EV_NONE) { 885be18010eSKefeng Wang pr_warn("failed to init libelf for %s\n", path); 886e6c64855SAndrii Nakryiko return ERR_PTR(-LIBBPF_ERRNO__LIBELF); 887e6c64855SAndrii Nakryiko } 888e6c64855SAndrii Nakryiko 889e6c64855SAndrii Nakryiko fd = open(path, O_RDONLY); 890e6c64855SAndrii Nakryiko if (fd < 0) { 891e6c64855SAndrii Nakryiko err = -errno; 892be18010eSKefeng Wang pr_warn("failed to open %s: %s\n", path, strerror(errno)); 893e6c64855SAndrii Nakryiko return ERR_PTR(err); 894e6c64855SAndrii Nakryiko } 895e6c64855SAndrii Nakryiko 896e6c64855SAndrii Nakryiko err = -LIBBPF_ERRNO__FORMAT; 897e6c64855SAndrii Nakryiko 898e6c64855SAndrii Nakryiko elf = elf_begin(fd, ELF_C_READ, NULL); 899e6c64855SAndrii Nakryiko if (!elf) { 900be18010eSKefeng Wang pr_warn("failed to open %s as ELF file\n", path); 901e6c64855SAndrii Nakryiko goto done; 902e6c64855SAndrii Nakryiko } 903e6c64855SAndrii Nakryiko if (!gelf_getehdr(elf, &ehdr)) { 904be18010eSKefeng Wang pr_warn("failed to get EHDR from %s\n", path); 905e6c64855SAndrii Nakryiko goto done; 906e6c64855SAndrii Nakryiko } 9076095d5a2SJiri Olsa 9086095d5a2SJiri Olsa if (elf_getshdrstrndx(elf, &shstrndx)) { 9096095d5a2SJiri Olsa pr_warn("failed to get section names section index for %s\n", 9106095d5a2SJiri Olsa path); 9116095d5a2SJiri Olsa goto done; 9126095d5a2SJiri Olsa } 9136095d5a2SJiri Olsa 9146095d5a2SJiri Olsa if (!elf_rawdata(elf_getscn(elf, shstrndx), NULL)) { 915be18010eSKefeng Wang pr_warn("failed to get e_shstrndx from %s\n", path); 916e6c64855SAndrii Nakryiko goto done; 917e6c64855SAndrii Nakryiko } 918e6c64855SAndrii Nakryiko 919e6c64855SAndrii Nakryiko while ((scn = elf_nextscn(elf, scn)) != NULL) { 920e6c64855SAndrii Nakryiko GElf_Shdr sh; 921e6c64855SAndrii Nakryiko char *name; 922e6c64855SAndrii Nakryiko 923e6c64855SAndrii Nakryiko idx++; 924e6c64855SAndrii Nakryiko if (gelf_getshdr(scn, &sh) != &sh) { 925be18010eSKefeng Wang pr_warn("failed to get section(%d) header from %s\n", 926e6c64855SAndrii Nakryiko idx, path); 927e6c64855SAndrii Nakryiko goto done; 928e6c64855SAndrii Nakryiko } 9296095d5a2SJiri Olsa name = elf_strptr(elf, shstrndx, sh.sh_name); 930e6c64855SAndrii Nakryiko if (!name) { 931be18010eSKefeng Wang pr_warn("failed to get section(%d) name from %s\n", 932e6c64855SAndrii Nakryiko idx, path); 933e6c64855SAndrii Nakryiko goto done; 934e6c64855SAndrii Nakryiko } 935e6c64855SAndrii Nakryiko if (strcmp(name, BTF_ELF_SEC) == 0) { 936e6c64855SAndrii Nakryiko btf_data = elf_getdata(scn, 0); 937e6c64855SAndrii Nakryiko if (!btf_data) { 938be18010eSKefeng Wang pr_warn("failed to get section(%d, %s) data from %s\n", 939e6c64855SAndrii Nakryiko idx, name, path); 940e6c64855SAndrii Nakryiko goto done; 941e6c64855SAndrii Nakryiko } 942e6c64855SAndrii Nakryiko continue; 943e6c64855SAndrii Nakryiko } else if (btf_ext && strcmp(name, BTF_EXT_ELF_SEC) == 0) { 944e6c64855SAndrii Nakryiko btf_ext_data = elf_getdata(scn, 0); 945e6c64855SAndrii Nakryiko if (!btf_ext_data) { 946be18010eSKefeng Wang pr_warn("failed to get section(%d, %s) data from %s\n", 947e6c64855SAndrii Nakryiko idx, name, path); 948e6c64855SAndrii Nakryiko goto done; 949e6c64855SAndrii Nakryiko } 950e6c64855SAndrii Nakryiko continue; 951e6c64855SAndrii Nakryiko } 952e6c64855SAndrii Nakryiko } 953e6c64855SAndrii Nakryiko 954e6c64855SAndrii Nakryiko err = 0; 955e6c64855SAndrii Nakryiko 956e6c64855SAndrii Nakryiko if (!btf_data) { 957e6c64855SAndrii Nakryiko err = -ENOENT; 958e6c64855SAndrii Nakryiko goto done; 959e6c64855SAndrii Nakryiko } 960ba451366SAndrii Nakryiko btf = btf_new(btf_data->d_buf, btf_data->d_size, base_btf); 961e9fc3ce9SAndrii Nakryiko err = libbpf_get_error(btf); 962e9fc3ce9SAndrii Nakryiko if (err) 963e6c64855SAndrii Nakryiko goto done; 964e6c64855SAndrii Nakryiko 96544ad23dfSAndrii Nakryiko switch (gelf_getclass(elf)) { 96644ad23dfSAndrii Nakryiko case ELFCLASS32: 96744ad23dfSAndrii Nakryiko btf__set_pointer_size(btf, 4); 96844ad23dfSAndrii Nakryiko break; 96944ad23dfSAndrii Nakryiko case ELFCLASS64: 97044ad23dfSAndrii Nakryiko btf__set_pointer_size(btf, 8); 97144ad23dfSAndrii Nakryiko break; 97244ad23dfSAndrii Nakryiko default: 97344ad23dfSAndrii Nakryiko pr_warn("failed to get ELF class (bitness) for %s\n", path); 97444ad23dfSAndrii Nakryiko break; 97544ad23dfSAndrii Nakryiko } 97644ad23dfSAndrii Nakryiko 977e6c64855SAndrii Nakryiko if (btf_ext && btf_ext_data) { 978e9fc3ce9SAndrii Nakryiko *btf_ext = btf_ext__new(btf_ext_data->d_buf, btf_ext_data->d_size); 979e9fc3ce9SAndrii Nakryiko err = libbpf_get_error(*btf_ext); 980e9fc3ce9SAndrii Nakryiko if (err) 981e6c64855SAndrii Nakryiko goto done; 982e6c64855SAndrii Nakryiko } else if (btf_ext) { 983e6c64855SAndrii Nakryiko *btf_ext = NULL; 984e6c64855SAndrii Nakryiko } 985e6c64855SAndrii Nakryiko done: 986e6c64855SAndrii Nakryiko if (elf) 987e6c64855SAndrii Nakryiko elf_end(elf); 988e6c64855SAndrii Nakryiko close(fd); 989e6c64855SAndrii Nakryiko 990e9fc3ce9SAndrii Nakryiko if (!err) 991e6c64855SAndrii Nakryiko return btf; 992e9fc3ce9SAndrii Nakryiko 993e9fc3ce9SAndrii Nakryiko if (btf_ext) 994e9fc3ce9SAndrii Nakryiko btf_ext__free(*btf_ext); 995e6c64855SAndrii Nakryiko btf__free(btf); 996e9fc3ce9SAndrii Nakryiko 997e6c64855SAndrii Nakryiko return ERR_PTR(err); 998e6c64855SAndrii Nakryiko } 999e6c64855SAndrii Nakryiko 1000ba451366SAndrii Nakryiko struct btf *btf__parse_elf(const char *path, struct btf_ext **btf_ext) 1001ba451366SAndrii Nakryiko { 1002e9fc3ce9SAndrii Nakryiko return libbpf_ptr(btf_parse_elf(path, NULL, btf_ext)); 1003ba451366SAndrii Nakryiko } 1004ba451366SAndrii Nakryiko 1005ba451366SAndrii Nakryiko struct btf *btf__parse_elf_split(const char *path, struct btf *base_btf) 1006ba451366SAndrii Nakryiko { 1007e9fc3ce9SAndrii Nakryiko return libbpf_ptr(btf_parse_elf(path, base_btf, NULL)); 1008ba451366SAndrii Nakryiko } 1009ba451366SAndrii Nakryiko 1010ba451366SAndrii Nakryiko static struct btf *btf_parse_raw(const char *path, struct btf *base_btf) 101194a1feddSAndrii Nakryiko { 1012932ac54aSDaniel T. Lee struct btf *btf = NULL; 101394a1feddSAndrii Nakryiko void *data = NULL; 101494a1feddSAndrii Nakryiko FILE *f = NULL; 101594a1feddSAndrii Nakryiko __u16 magic; 101694a1feddSAndrii Nakryiko int err = 0; 101794a1feddSAndrii Nakryiko long sz; 101894a1feddSAndrii Nakryiko 101994a1feddSAndrii Nakryiko f = fopen(path, "rb"); 102094a1feddSAndrii Nakryiko if (!f) { 102194a1feddSAndrii Nakryiko err = -errno; 102294a1feddSAndrii Nakryiko goto err_out; 102394a1feddSAndrii Nakryiko } 102494a1feddSAndrii Nakryiko 102594a1feddSAndrii Nakryiko /* check BTF magic */ 102694a1feddSAndrii Nakryiko if (fread(&magic, 1, sizeof(magic), f) < sizeof(magic)) { 102794a1feddSAndrii Nakryiko err = -EIO; 102894a1feddSAndrii Nakryiko goto err_out; 102994a1feddSAndrii Nakryiko } 10303289959bSAndrii Nakryiko if (magic != BTF_MAGIC && magic != bswap_16(BTF_MAGIC)) { 103194a1feddSAndrii Nakryiko /* definitely not a raw BTF */ 103294a1feddSAndrii Nakryiko err = -EPROTO; 103394a1feddSAndrii Nakryiko goto err_out; 103494a1feddSAndrii Nakryiko } 103594a1feddSAndrii Nakryiko 103694a1feddSAndrii Nakryiko /* get file size */ 103794a1feddSAndrii Nakryiko if (fseek(f, 0, SEEK_END)) { 103894a1feddSAndrii Nakryiko err = -errno; 103994a1feddSAndrii Nakryiko goto err_out; 104094a1feddSAndrii Nakryiko } 104194a1feddSAndrii Nakryiko sz = ftell(f); 104294a1feddSAndrii Nakryiko if (sz < 0) { 104394a1feddSAndrii Nakryiko err = -errno; 104494a1feddSAndrii Nakryiko goto err_out; 104594a1feddSAndrii Nakryiko } 104694a1feddSAndrii Nakryiko /* rewind to the start */ 104794a1feddSAndrii Nakryiko if (fseek(f, 0, SEEK_SET)) { 104894a1feddSAndrii Nakryiko err = -errno; 104994a1feddSAndrii Nakryiko goto err_out; 105094a1feddSAndrii Nakryiko } 105194a1feddSAndrii Nakryiko 105294a1feddSAndrii Nakryiko /* pre-alloc memory and read all of BTF data */ 105394a1feddSAndrii Nakryiko data = malloc(sz); 105494a1feddSAndrii Nakryiko if (!data) { 105594a1feddSAndrii Nakryiko err = -ENOMEM; 105694a1feddSAndrii Nakryiko goto err_out; 105794a1feddSAndrii Nakryiko } 105894a1feddSAndrii Nakryiko if (fread(data, 1, sz, f) < sz) { 105994a1feddSAndrii Nakryiko err = -EIO; 106094a1feddSAndrii Nakryiko goto err_out; 106194a1feddSAndrii Nakryiko } 106294a1feddSAndrii Nakryiko 106394a1feddSAndrii Nakryiko /* finally parse BTF data */ 1064ba451366SAndrii Nakryiko btf = btf_new(data, sz, base_btf); 106594a1feddSAndrii Nakryiko 106694a1feddSAndrii Nakryiko err_out: 106794a1feddSAndrii Nakryiko free(data); 106894a1feddSAndrii Nakryiko if (f) 106994a1feddSAndrii Nakryiko fclose(f); 107094a1feddSAndrii Nakryiko return err ? ERR_PTR(err) : btf; 107194a1feddSAndrii Nakryiko } 107294a1feddSAndrii Nakryiko 1073ba451366SAndrii Nakryiko struct btf *btf__parse_raw(const char *path) 1074ba451366SAndrii Nakryiko { 1075e9fc3ce9SAndrii Nakryiko return libbpf_ptr(btf_parse_raw(path, NULL)); 1076ba451366SAndrii Nakryiko } 1077ba451366SAndrii Nakryiko 1078ba451366SAndrii Nakryiko struct btf *btf__parse_raw_split(const char *path, struct btf *base_btf) 1079ba451366SAndrii Nakryiko { 1080e9fc3ce9SAndrii Nakryiko return libbpf_ptr(btf_parse_raw(path, base_btf)); 1081ba451366SAndrii Nakryiko } 1082ba451366SAndrii Nakryiko 1083ba451366SAndrii Nakryiko static struct btf *btf_parse(const char *path, struct btf *base_btf, struct btf_ext **btf_ext) 108494a1feddSAndrii Nakryiko { 108594a1feddSAndrii Nakryiko struct btf *btf; 1086e9fc3ce9SAndrii Nakryiko int err; 108794a1feddSAndrii Nakryiko 108894a1feddSAndrii Nakryiko if (btf_ext) 108994a1feddSAndrii Nakryiko *btf_ext = NULL; 109094a1feddSAndrii Nakryiko 1091ba451366SAndrii Nakryiko btf = btf_parse_raw(path, base_btf); 1092e9fc3ce9SAndrii Nakryiko err = libbpf_get_error(btf); 1093e9fc3ce9SAndrii Nakryiko if (!err) 109494a1feddSAndrii Nakryiko return btf; 1095e9fc3ce9SAndrii Nakryiko if (err != -EPROTO) 1096e9fc3ce9SAndrii Nakryiko return ERR_PTR(err); 1097ba451366SAndrii Nakryiko return btf_parse_elf(path, base_btf, btf_ext); 1098ba451366SAndrii Nakryiko } 1099ba451366SAndrii Nakryiko 1100ba451366SAndrii Nakryiko struct btf *btf__parse(const char *path, struct btf_ext **btf_ext) 1101ba451366SAndrii Nakryiko { 1102e9fc3ce9SAndrii Nakryiko return libbpf_ptr(btf_parse(path, NULL, btf_ext)); 1103ba451366SAndrii Nakryiko } 1104ba451366SAndrii Nakryiko 1105ba451366SAndrii Nakryiko struct btf *btf__parse_split(const char *path, struct btf *base_btf) 1106ba451366SAndrii Nakryiko { 1107e9fc3ce9SAndrii Nakryiko return libbpf_ptr(btf_parse(path, base_btf, NULL)); 110894a1feddSAndrii Nakryiko } 110994a1feddSAndrii Nakryiko 11103289959bSAndrii Nakryiko static void *btf_get_raw_data(const struct btf *btf, __u32 *size, bool swap_endian); 11113289959bSAndrii Nakryiko 11123c7e5859SQuentin Monnet int btf__load_into_kernel(struct btf *btf) 1113d29d87f7SAndrii Nakryiko { 1114b8604247SAndrii Nakryiko __u32 log_buf_size = 0, raw_size; 1115d29d87f7SAndrii Nakryiko char *log_buf = NULL; 11163289959bSAndrii Nakryiko void *raw_data; 1117d29d87f7SAndrii Nakryiko int err = 0; 1118d29d87f7SAndrii Nakryiko 1119d29d87f7SAndrii Nakryiko if (btf->fd >= 0) 1120e9fc3ce9SAndrii Nakryiko return libbpf_err(-EEXIST); 1121d29d87f7SAndrii Nakryiko 11228395f320SStanislav Fomichev retry_load: 11238395f320SStanislav Fomichev if (log_buf_size) { 1124d29d87f7SAndrii Nakryiko log_buf = malloc(log_buf_size); 1125d29d87f7SAndrii Nakryiko if (!log_buf) 1126e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 1127d29d87f7SAndrii Nakryiko 1128d29d87f7SAndrii Nakryiko *log_buf = 0; 11298395f320SStanislav Fomichev } 1130d29d87f7SAndrii Nakryiko 11313289959bSAndrii Nakryiko raw_data = btf_get_raw_data(btf, &raw_size, false); 1132b8604247SAndrii Nakryiko if (!raw_data) { 1133b8604247SAndrii Nakryiko err = -ENOMEM; 1134b8604247SAndrii Nakryiko goto done; 1135b8604247SAndrii Nakryiko } 11363289959bSAndrii Nakryiko /* cache native raw data representation */ 11373289959bSAndrii Nakryiko btf->raw_size = raw_size; 11383289959bSAndrii Nakryiko btf->raw_data = raw_data; 1139b8604247SAndrii Nakryiko 1140b8604247SAndrii Nakryiko btf->fd = bpf_load_btf(raw_data, raw_size, log_buf, log_buf_size, false); 1141d29d87f7SAndrii Nakryiko if (btf->fd < 0) { 11428395f320SStanislav Fomichev if (!log_buf || errno == ENOSPC) { 11438395f320SStanislav Fomichev log_buf_size = max((__u32)BPF_LOG_BUF_SIZE, 11448395f320SStanislav Fomichev log_buf_size << 1); 11458395f320SStanislav Fomichev free(log_buf); 11468395f320SStanislav Fomichev goto retry_load; 11478395f320SStanislav Fomichev } 11488395f320SStanislav Fomichev 1149d29d87f7SAndrii Nakryiko err = -errno; 1150be18010eSKefeng Wang pr_warn("Error loading BTF: %s(%d)\n", strerror(errno), errno); 1151d29d87f7SAndrii Nakryiko if (*log_buf) 1152be18010eSKefeng Wang pr_warn("%s\n", log_buf); 1153d29d87f7SAndrii Nakryiko goto done; 1154d29d87f7SAndrii Nakryiko } 1155d29d87f7SAndrii Nakryiko 1156d29d87f7SAndrii Nakryiko done: 1157d29d87f7SAndrii Nakryiko free(log_buf); 1158e9fc3ce9SAndrii Nakryiko return libbpf_err(err); 1159d29d87f7SAndrii Nakryiko } 11603c7e5859SQuentin Monnet int btf__load(struct btf *) __attribute__((alias("btf__load_into_kernel"))); 1161d29d87f7SAndrii Nakryiko 11628a138aedSMartin KaFai Lau int btf__fd(const struct btf *btf) 11638a138aedSMartin KaFai Lau { 11648a138aedSMartin KaFai Lau return btf->fd; 11658a138aedSMartin KaFai Lau } 116692b57121SOkash Khawaja 116781372e12SAndrii Nakryiko void btf__set_fd(struct btf *btf, int fd) 116881372e12SAndrii Nakryiko { 116981372e12SAndrii Nakryiko btf->fd = fd; 117081372e12SAndrii Nakryiko } 117181372e12SAndrii Nakryiko 117290d76d3eSAndrii Nakryiko static const void *btf_strs_data(const struct btf *btf) 117390d76d3eSAndrii Nakryiko { 117490d76d3eSAndrii Nakryiko return btf->strs_data ? btf->strs_data : strset__data(btf->strs_set); 117590d76d3eSAndrii Nakryiko } 117690d76d3eSAndrii Nakryiko 11773289959bSAndrii Nakryiko static void *btf_get_raw_data(const struct btf *btf, __u32 *size, bool swap_endian) 11783289959bSAndrii Nakryiko { 11793289959bSAndrii Nakryiko struct btf_header *hdr = btf->hdr; 11803289959bSAndrii Nakryiko struct btf_type *t; 11813289959bSAndrii Nakryiko void *data, *p; 11823289959bSAndrii Nakryiko __u32 data_sz; 11833289959bSAndrii Nakryiko int i; 11843289959bSAndrii Nakryiko 11853289959bSAndrii Nakryiko data = swap_endian ? btf->raw_data_swapped : btf->raw_data; 11863289959bSAndrii Nakryiko if (data) { 11873289959bSAndrii Nakryiko *size = btf->raw_size; 11883289959bSAndrii Nakryiko return data; 11893289959bSAndrii Nakryiko } 11903289959bSAndrii Nakryiko 11913289959bSAndrii Nakryiko data_sz = hdr->hdr_len + hdr->type_len + hdr->str_len; 11923289959bSAndrii Nakryiko data = calloc(1, data_sz); 11933289959bSAndrii Nakryiko if (!data) 11943289959bSAndrii Nakryiko return NULL; 11953289959bSAndrii Nakryiko p = data; 11963289959bSAndrii Nakryiko 11973289959bSAndrii Nakryiko memcpy(p, hdr, hdr->hdr_len); 11983289959bSAndrii Nakryiko if (swap_endian) 11993289959bSAndrii Nakryiko btf_bswap_hdr(p); 12003289959bSAndrii Nakryiko p += hdr->hdr_len; 12013289959bSAndrii Nakryiko 12023289959bSAndrii Nakryiko memcpy(p, btf->types_data, hdr->type_len); 12033289959bSAndrii Nakryiko if (swap_endian) { 1204ba451366SAndrii Nakryiko for (i = 0; i < btf->nr_types; i++) { 12053289959bSAndrii Nakryiko t = p + btf->type_offs[i]; 12063289959bSAndrii Nakryiko /* btf_bswap_type_rest() relies on native t->info, so 12073289959bSAndrii Nakryiko * we swap base type info after we swapped all the 12083289959bSAndrii Nakryiko * additional information 12093289959bSAndrii Nakryiko */ 12103289959bSAndrii Nakryiko if (btf_bswap_type_rest(t)) 12113289959bSAndrii Nakryiko goto err_out; 12123289959bSAndrii Nakryiko btf_bswap_type_base(t); 12133289959bSAndrii Nakryiko } 12143289959bSAndrii Nakryiko } 12153289959bSAndrii Nakryiko p += hdr->type_len; 12163289959bSAndrii Nakryiko 121790d76d3eSAndrii Nakryiko memcpy(p, btf_strs_data(btf), hdr->str_len); 12183289959bSAndrii Nakryiko p += hdr->str_len; 12193289959bSAndrii Nakryiko 12203289959bSAndrii Nakryiko *size = data_sz; 12213289959bSAndrii Nakryiko return data; 12223289959bSAndrii Nakryiko err_out: 12233289959bSAndrii Nakryiko free(data); 12243289959bSAndrii Nakryiko return NULL; 12253289959bSAndrii Nakryiko } 12263289959bSAndrii Nakryiko 1227919d2b1dSAndrii Nakryiko const void *btf__get_raw_data(const struct btf *btf_ro, __u32 *size) 122802c87446SAndrii Nakryiko { 1229919d2b1dSAndrii Nakryiko struct btf *btf = (struct btf *)btf_ro; 12303289959bSAndrii Nakryiko __u32 data_sz; 1231919d2b1dSAndrii Nakryiko void *data; 1232919d2b1dSAndrii Nakryiko 12333289959bSAndrii Nakryiko data = btf_get_raw_data(btf, &data_sz, btf->swapped_endian); 12343289959bSAndrii Nakryiko if (!data) 1235e9fc3ce9SAndrii Nakryiko return errno = -ENOMEM, NULL; 1236919d2b1dSAndrii Nakryiko 12373289959bSAndrii Nakryiko btf->raw_size = data_sz; 12383289959bSAndrii Nakryiko if (btf->swapped_endian) 12393289959bSAndrii Nakryiko btf->raw_data_swapped = data; 12403289959bSAndrii Nakryiko else 12413289959bSAndrii Nakryiko btf->raw_data = data; 12423289959bSAndrii Nakryiko *size = data_sz; 12433289959bSAndrii Nakryiko return data; 124402c87446SAndrii Nakryiko } 124502c87446SAndrii Nakryiko 1246f86ed050SAndrii Nakryiko const char *btf__str_by_offset(const struct btf *btf, __u32 offset) 124792b57121SOkash Khawaja { 1248ba451366SAndrii Nakryiko if (offset < btf->start_str_off) 1249ba451366SAndrii Nakryiko return btf__str_by_offset(btf->base_btf, offset); 1250ba451366SAndrii Nakryiko else if (offset - btf->start_str_off < btf->hdr->str_len) 125190d76d3eSAndrii Nakryiko return btf_strs_data(btf) + (offset - btf->start_str_off); 125292b57121SOkash Khawaja else 1253e9fc3ce9SAndrii Nakryiko return errno = EINVAL, NULL; 125492b57121SOkash Khawaja } 12552993e051SYonghong Song 1256f86ed050SAndrii Nakryiko const char *btf__name_by_offset(const struct btf *btf, __u32 offset) 1257f86ed050SAndrii Nakryiko { 1258f86ed050SAndrii Nakryiko return btf__str_by_offset(btf, offset); 1259f86ed050SAndrii Nakryiko } 1260f86ed050SAndrii Nakryiko 1261a19f93cfSAndrii Nakryiko struct btf *btf_get_from_fd(int btf_fd, struct btf *base_btf) 1262d7f5b5e0SYonghong Song { 1263a19f93cfSAndrii Nakryiko struct bpf_btf_info btf_info; 1264d7f5b5e0SYonghong Song __u32 len = sizeof(btf_info); 1265d7f5b5e0SYonghong Song __u32 last_size; 1266a19f93cfSAndrii Nakryiko struct btf *btf; 1267d7f5b5e0SYonghong Song void *ptr; 1268d7f5b5e0SYonghong Song int err; 1269d7f5b5e0SYonghong Song 1270d7f5b5e0SYonghong Song /* we won't know btf_size until we call bpf_obj_get_info_by_fd(). so 1271d7f5b5e0SYonghong Song * let's start with a sane default - 4KiB here - and resize it only if 1272d7f5b5e0SYonghong Song * bpf_obj_get_info_by_fd() needs a bigger buffer. 1273d7f5b5e0SYonghong Song */ 1274a19f93cfSAndrii Nakryiko last_size = 4096; 1275d7f5b5e0SYonghong Song ptr = malloc(last_size); 1276a19f93cfSAndrii Nakryiko if (!ptr) 1277a19f93cfSAndrii Nakryiko return ERR_PTR(-ENOMEM); 1278d7f5b5e0SYonghong Song 1279a19f93cfSAndrii Nakryiko memset(&btf_info, 0, sizeof(btf_info)); 1280d7f5b5e0SYonghong Song btf_info.btf = ptr_to_u64(ptr); 1281a19f93cfSAndrii Nakryiko btf_info.btf_size = last_size; 1282d7f5b5e0SYonghong Song err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len); 1283d7f5b5e0SYonghong Song 1284d7f5b5e0SYonghong Song if (!err && btf_info.btf_size > last_size) { 1285d7f5b5e0SYonghong Song void *temp_ptr; 1286d7f5b5e0SYonghong Song 1287d7f5b5e0SYonghong Song last_size = btf_info.btf_size; 1288d7f5b5e0SYonghong Song temp_ptr = realloc(ptr, last_size); 1289d7f5b5e0SYonghong Song if (!temp_ptr) { 1290a19f93cfSAndrii Nakryiko btf = ERR_PTR(-ENOMEM); 1291d7f5b5e0SYonghong Song goto exit_free; 1292d7f5b5e0SYonghong Song } 1293d7f5b5e0SYonghong Song ptr = temp_ptr; 1294a19f93cfSAndrii Nakryiko 1295a19f93cfSAndrii Nakryiko len = sizeof(btf_info); 1296a19f93cfSAndrii Nakryiko memset(&btf_info, 0, sizeof(btf_info)); 1297d7f5b5e0SYonghong Song btf_info.btf = ptr_to_u64(ptr); 1298a19f93cfSAndrii Nakryiko btf_info.btf_size = last_size; 1299a19f93cfSAndrii Nakryiko 1300d7f5b5e0SYonghong Song err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len); 1301d7f5b5e0SYonghong Song } 1302d7f5b5e0SYonghong Song 1303d7f5b5e0SYonghong Song if (err || btf_info.btf_size > last_size) { 1304a19f93cfSAndrii Nakryiko btf = err ? ERR_PTR(-errno) : ERR_PTR(-E2BIG); 1305d7f5b5e0SYonghong Song goto exit_free; 1306d7f5b5e0SYonghong Song } 1307d7f5b5e0SYonghong Song 1308a19f93cfSAndrii Nakryiko btf = btf_new(ptr, btf_info.btf_size, base_btf); 1309d7f5b5e0SYonghong Song 1310d7f5b5e0SYonghong Song exit_free: 1311d7f5b5e0SYonghong Song free(ptr); 1312a19f93cfSAndrii Nakryiko return btf; 1313a19f93cfSAndrii Nakryiko } 1314d7f5b5e0SYonghong Song 131561fc51b1SQuentin Monnet struct btf *btf__load_from_kernel_by_id_split(__u32 id, struct btf *base_btf) 13166cc93e2fSQuentin Monnet { 13176cc93e2fSQuentin Monnet struct btf *btf; 13186cc93e2fSQuentin Monnet int btf_fd; 13196cc93e2fSQuentin Monnet 13206cc93e2fSQuentin Monnet btf_fd = bpf_btf_get_fd_by_id(id); 13216cc93e2fSQuentin Monnet if (btf_fd < 0) 13226cc93e2fSQuentin Monnet return libbpf_err_ptr(-errno); 13236cc93e2fSQuentin Monnet 132461fc51b1SQuentin Monnet btf = btf_get_from_fd(btf_fd, base_btf); 13256cc93e2fSQuentin Monnet close(btf_fd); 13266cc93e2fSQuentin Monnet 13276cc93e2fSQuentin Monnet return libbpf_ptr(btf); 13286cc93e2fSQuentin Monnet } 13296cc93e2fSQuentin Monnet 133061fc51b1SQuentin Monnet struct btf *btf__load_from_kernel_by_id(__u32 id) 133161fc51b1SQuentin Monnet { 133261fc51b1SQuentin Monnet return btf__load_from_kernel_by_id_split(id, NULL); 133361fc51b1SQuentin Monnet } 133461fc51b1SQuentin Monnet 1335a19f93cfSAndrii Nakryiko int btf__get_from_id(__u32 id, struct btf **btf) 1336a19f93cfSAndrii Nakryiko { 1337a19f93cfSAndrii Nakryiko struct btf *res; 13386cc93e2fSQuentin Monnet int err; 1339a19f93cfSAndrii Nakryiko 1340a19f93cfSAndrii Nakryiko *btf = NULL; 13416cc93e2fSQuentin Monnet res = btf__load_from_kernel_by_id(id); 1342e9fc3ce9SAndrii Nakryiko err = libbpf_get_error(res); 1343e9fc3ce9SAndrii Nakryiko 1344e9fc3ce9SAndrii Nakryiko if (err) 1345e9fc3ce9SAndrii Nakryiko return libbpf_err(err); 1346a19f93cfSAndrii Nakryiko 1347a19f93cfSAndrii Nakryiko *btf = res; 1348a19f93cfSAndrii Nakryiko return 0; 1349d7f5b5e0SYonghong Song } 1350d7f5b5e0SYonghong Song 1351a6c109a6SYonghong Song int btf__get_map_kv_tids(const struct btf *btf, const char *map_name, 135296408c43SYonghong Song __u32 expected_key_size, __u32 expected_value_size, 135396408c43SYonghong Song __u32 *key_type_id, __u32 *value_type_id) 135496408c43SYonghong Song { 135596408c43SYonghong Song const struct btf_type *container_type; 135696408c43SYonghong Song const struct btf_member *key, *value; 135796408c43SYonghong Song const size_t max_name = 256; 135896408c43SYonghong Song char container_name[max_name]; 135996408c43SYonghong Song __s64 key_size, value_size; 136096408c43SYonghong Song __s32 container_id; 136196408c43SYonghong Song 1362e9fc3ce9SAndrii Nakryiko if (snprintf(container_name, max_name, "____btf_map_%s", map_name) == max_name) { 1363be18010eSKefeng Wang pr_warn("map:%s length of '____btf_map_%s' is too long\n", 136496408c43SYonghong Song map_name, map_name); 1365e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 136696408c43SYonghong Song } 136796408c43SYonghong Song 136896408c43SYonghong Song container_id = btf__find_by_name(btf, container_name); 136996408c43SYonghong Song if (container_id < 0) { 1370f7748e29SYonghong Song pr_debug("map:%s container_name:%s cannot be found in BTF. Missing BPF_ANNOTATE_KV_PAIR?\n", 137196408c43SYonghong Song map_name, container_name); 1372e9fc3ce9SAndrii Nakryiko return libbpf_err(container_id); 137396408c43SYonghong Song } 137496408c43SYonghong Song 137596408c43SYonghong Song container_type = btf__type_by_id(btf, container_id); 137696408c43SYonghong Song if (!container_type) { 1377be18010eSKefeng Wang pr_warn("map:%s cannot find BTF type for container_id:%u\n", 137896408c43SYonghong Song map_name, container_id); 1379e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 138096408c43SYonghong Song } 138196408c43SYonghong Song 1382b03bc685SAndrii Nakryiko if (!btf_is_struct(container_type) || btf_vlen(container_type) < 2) { 1383be18010eSKefeng Wang pr_warn("map:%s container_name:%s is an invalid container struct\n", 138496408c43SYonghong Song map_name, container_name); 1385e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 138696408c43SYonghong Song } 138796408c43SYonghong Song 1388b03bc685SAndrii Nakryiko key = btf_members(container_type); 138996408c43SYonghong Song value = key + 1; 139096408c43SYonghong Song 139196408c43SYonghong Song key_size = btf__resolve_size(btf, key->type); 139296408c43SYonghong Song if (key_size < 0) { 1393be18010eSKefeng Wang pr_warn("map:%s invalid BTF key_type_size\n", map_name); 1394e9fc3ce9SAndrii Nakryiko return libbpf_err(key_size); 139596408c43SYonghong Song } 139696408c43SYonghong Song 139796408c43SYonghong Song if (expected_key_size != key_size) { 1398be18010eSKefeng Wang pr_warn("map:%s btf_key_type_size:%u != map_def_key_size:%u\n", 139996408c43SYonghong Song map_name, (__u32)key_size, expected_key_size); 1400e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 140196408c43SYonghong Song } 140296408c43SYonghong Song 140396408c43SYonghong Song value_size = btf__resolve_size(btf, value->type); 140496408c43SYonghong Song if (value_size < 0) { 1405be18010eSKefeng Wang pr_warn("map:%s invalid BTF value_type_size\n", map_name); 1406e9fc3ce9SAndrii Nakryiko return libbpf_err(value_size); 140796408c43SYonghong Song } 140896408c43SYonghong Song 140996408c43SYonghong Song if (expected_value_size != value_size) { 1410be18010eSKefeng Wang pr_warn("map:%s btf_value_type_size:%u != map_def_value_size:%u\n", 141196408c43SYonghong Song map_name, (__u32)value_size, expected_value_size); 1412e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 141396408c43SYonghong Song } 141496408c43SYonghong Song 141596408c43SYonghong Song *key_type_id = key->type; 141696408c43SYonghong Song *value_type_id = value->type; 141796408c43SYonghong Song 141896408c43SYonghong Song return 0; 141996408c43SYonghong Song } 142096408c43SYonghong Song 14213289959bSAndrii Nakryiko static void btf_invalidate_raw_data(struct btf *btf) 14223289959bSAndrii Nakryiko { 14233289959bSAndrii Nakryiko if (btf->raw_data) { 14243289959bSAndrii Nakryiko free(btf->raw_data); 14253289959bSAndrii Nakryiko btf->raw_data = NULL; 14263289959bSAndrii Nakryiko } 14273289959bSAndrii Nakryiko if (btf->raw_data_swapped) { 14283289959bSAndrii Nakryiko free(btf->raw_data_swapped); 14293289959bSAndrii Nakryiko btf->raw_data_swapped = NULL; 14303289959bSAndrii Nakryiko } 14313289959bSAndrii Nakryiko } 14323289959bSAndrii Nakryiko 1433919d2b1dSAndrii Nakryiko /* Ensure BTF is ready to be modified (by splitting into a three memory 1434919d2b1dSAndrii Nakryiko * regions for header, types, and strings). Also invalidate cached 1435919d2b1dSAndrii Nakryiko * raw_data, if any. 1436919d2b1dSAndrii Nakryiko */ 1437919d2b1dSAndrii Nakryiko static int btf_ensure_modifiable(struct btf *btf) 1438919d2b1dSAndrii Nakryiko { 143990d76d3eSAndrii Nakryiko void *hdr, *types; 144090d76d3eSAndrii Nakryiko struct strset *set = NULL; 144190d76d3eSAndrii Nakryiko int err = -ENOMEM; 1442919d2b1dSAndrii Nakryiko 1443919d2b1dSAndrii Nakryiko if (btf_is_modifiable(btf)) { 1444919d2b1dSAndrii Nakryiko /* any BTF modification invalidates raw_data */ 14453289959bSAndrii Nakryiko btf_invalidate_raw_data(btf); 1446919d2b1dSAndrii Nakryiko return 0; 1447919d2b1dSAndrii Nakryiko } 1448919d2b1dSAndrii Nakryiko 1449919d2b1dSAndrii Nakryiko /* split raw data into three memory regions */ 1450919d2b1dSAndrii Nakryiko hdr = malloc(btf->hdr->hdr_len); 1451919d2b1dSAndrii Nakryiko types = malloc(btf->hdr->type_len); 145290d76d3eSAndrii Nakryiko if (!hdr || !types) 1453919d2b1dSAndrii Nakryiko goto err_out; 1454919d2b1dSAndrii Nakryiko 1455919d2b1dSAndrii Nakryiko memcpy(hdr, btf->hdr, btf->hdr->hdr_len); 1456919d2b1dSAndrii Nakryiko memcpy(types, btf->types_data, btf->hdr->type_len); 145788a82c2aSAndrii Nakryiko 1458919d2b1dSAndrii Nakryiko /* build lookup index for all strings */ 145990d76d3eSAndrii Nakryiko set = strset__new(BTF_MAX_STR_OFFSET, btf->strs_data, btf->hdr->str_len); 146090d76d3eSAndrii Nakryiko if (IS_ERR(set)) { 146190d76d3eSAndrii Nakryiko err = PTR_ERR(set); 1462919d2b1dSAndrii Nakryiko goto err_out; 1463919d2b1dSAndrii Nakryiko } 1464919d2b1dSAndrii Nakryiko 1465919d2b1dSAndrii Nakryiko /* only when everything was successful, update internal state */ 1466919d2b1dSAndrii Nakryiko btf->hdr = hdr; 1467919d2b1dSAndrii Nakryiko btf->types_data = types; 1468919d2b1dSAndrii Nakryiko btf->types_data_cap = btf->hdr->type_len; 146990d76d3eSAndrii Nakryiko btf->strs_data = NULL; 147090d76d3eSAndrii Nakryiko btf->strs_set = set; 1471919d2b1dSAndrii Nakryiko /* if BTF was created from scratch, all strings are guaranteed to be 1472919d2b1dSAndrii Nakryiko * unique and deduplicated 1473919d2b1dSAndrii Nakryiko */ 1474ba451366SAndrii Nakryiko if (btf->hdr->str_len == 0) 1475ba451366SAndrii Nakryiko btf->strs_deduped = true; 1476ba451366SAndrii Nakryiko if (!btf->base_btf && btf->hdr->str_len == 1) 1477ba451366SAndrii Nakryiko btf->strs_deduped = true; 1478919d2b1dSAndrii Nakryiko 1479919d2b1dSAndrii Nakryiko /* invalidate raw_data representation */ 14803289959bSAndrii Nakryiko btf_invalidate_raw_data(btf); 1481919d2b1dSAndrii Nakryiko 1482919d2b1dSAndrii Nakryiko return 0; 1483919d2b1dSAndrii Nakryiko 1484919d2b1dSAndrii Nakryiko err_out: 148590d76d3eSAndrii Nakryiko strset__free(set); 1486919d2b1dSAndrii Nakryiko free(hdr); 1487919d2b1dSAndrii Nakryiko free(types); 148890d76d3eSAndrii Nakryiko return err; 1489919d2b1dSAndrii Nakryiko } 1490919d2b1dSAndrii Nakryiko 1491919d2b1dSAndrii Nakryiko /* Find an offset in BTF string section that corresponds to a given string *s*. 1492919d2b1dSAndrii Nakryiko * Returns: 1493919d2b1dSAndrii Nakryiko * - >0 offset into string section, if string is found; 1494919d2b1dSAndrii Nakryiko * - -ENOENT, if string is not in the string section; 1495919d2b1dSAndrii Nakryiko * - <0, on any other error. 1496919d2b1dSAndrii Nakryiko */ 1497919d2b1dSAndrii Nakryiko int btf__find_str(struct btf *btf, const char *s) 1498919d2b1dSAndrii Nakryiko { 149990d76d3eSAndrii Nakryiko int off; 1500919d2b1dSAndrii Nakryiko 1501ba451366SAndrii Nakryiko if (btf->base_btf) { 150290d76d3eSAndrii Nakryiko off = btf__find_str(btf->base_btf, s); 150390d76d3eSAndrii Nakryiko if (off != -ENOENT) 150490d76d3eSAndrii Nakryiko return off; 1505ba451366SAndrii Nakryiko } 1506ba451366SAndrii Nakryiko 1507919d2b1dSAndrii Nakryiko /* BTF needs to be in a modifiable state to build string lookup index */ 1508919d2b1dSAndrii Nakryiko if (btf_ensure_modifiable(btf)) 1509e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 1510919d2b1dSAndrii Nakryiko 151190d76d3eSAndrii Nakryiko off = strset__find_str(btf->strs_set, s); 151290d76d3eSAndrii Nakryiko if (off < 0) 1513e9fc3ce9SAndrii Nakryiko return libbpf_err(off); 1514919d2b1dSAndrii Nakryiko 151590d76d3eSAndrii Nakryiko return btf->start_str_off + off; 1516919d2b1dSAndrii Nakryiko } 1517919d2b1dSAndrii Nakryiko 1518919d2b1dSAndrii Nakryiko /* Add a string s to the BTF string section. 1519919d2b1dSAndrii Nakryiko * Returns: 1520919d2b1dSAndrii Nakryiko * - > 0 offset into string section, on success; 1521919d2b1dSAndrii Nakryiko * - < 0, on error. 1522919d2b1dSAndrii Nakryiko */ 1523919d2b1dSAndrii Nakryiko int btf__add_str(struct btf *btf, const char *s) 1524919d2b1dSAndrii Nakryiko { 152590d76d3eSAndrii Nakryiko int off; 1526919d2b1dSAndrii Nakryiko 1527ba451366SAndrii Nakryiko if (btf->base_btf) { 152890d76d3eSAndrii Nakryiko off = btf__find_str(btf->base_btf, s); 152990d76d3eSAndrii Nakryiko if (off != -ENOENT) 153090d76d3eSAndrii Nakryiko return off; 1531ba451366SAndrii Nakryiko } 1532ba451366SAndrii Nakryiko 1533919d2b1dSAndrii Nakryiko if (btf_ensure_modifiable(btf)) 1534e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 1535919d2b1dSAndrii Nakryiko 153690d76d3eSAndrii Nakryiko off = strset__add_str(btf->strs_set, s); 153790d76d3eSAndrii Nakryiko if (off < 0) 1538e9fc3ce9SAndrii Nakryiko return libbpf_err(off); 1539919d2b1dSAndrii Nakryiko 154090d76d3eSAndrii Nakryiko btf->hdr->str_len = strset__data_size(btf->strs_set); 1541919d2b1dSAndrii Nakryiko 154290d76d3eSAndrii Nakryiko return btf->start_str_off + off; 1543919d2b1dSAndrii Nakryiko } 1544919d2b1dSAndrii Nakryiko 15454a3b33f8SAndrii Nakryiko static void *btf_add_type_mem(struct btf *btf, size_t add_sz) 15464a3b33f8SAndrii Nakryiko { 15473b029e06SAndrii Nakryiko return libbpf_add_mem(&btf->types_data, &btf->types_data_cap, 1, 15484a3b33f8SAndrii Nakryiko btf->hdr->type_len, UINT_MAX, add_sz); 15494a3b33f8SAndrii Nakryiko } 15504a3b33f8SAndrii Nakryiko 15514a3b33f8SAndrii Nakryiko static void btf_type_inc_vlen(struct btf_type *t) 15524a3b33f8SAndrii Nakryiko { 15534a3b33f8SAndrii Nakryiko t->info = btf_type_info(btf_kind(t), btf_vlen(t) + 1, btf_kflag(t)); 15544a3b33f8SAndrii Nakryiko } 15554a3b33f8SAndrii Nakryiko 1556c81ed6d8SAndrii Nakryiko static int btf_commit_type(struct btf *btf, int data_sz) 1557c81ed6d8SAndrii Nakryiko { 1558c81ed6d8SAndrii Nakryiko int err; 1559c81ed6d8SAndrii Nakryiko 1560c81ed6d8SAndrii Nakryiko err = btf_add_type_idx_entry(btf, btf->hdr->type_len); 1561c81ed6d8SAndrii Nakryiko if (err) 1562e9fc3ce9SAndrii Nakryiko return libbpf_err(err); 1563c81ed6d8SAndrii Nakryiko 1564c81ed6d8SAndrii Nakryiko btf->hdr->type_len += data_sz; 1565c81ed6d8SAndrii Nakryiko btf->hdr->str_off += data_sz; 1566c81ed6d8SAndrii Nakryiko btf->nr_types++; 1567ba451366SAndrii Nakryiko return btf->start_id + btf->nr_types - 1; 1568c81ed6d8SAndrii Nakryiko } 1569c81ed6d8SAndrii Nakryiko 15709af44bc5SAndrii Nakryiko struct btf_pipe { 15719af44bc5SAndrii Nakryiko const struct btf *src; 15729af44bc5SAndrii Nakryiko struct btf *dst; 15739af44bc5SAndrii Nakryiko }; 15749af44bc5SAndrii Nakryiko 15759af44bc5SAndrii Nakryiko static int btf_rewrite_str(__u32 *str_off, void *ctx) 15769af44bc5SAndrii Nakryiko { 15779af44bc5SAndrii Nakryiko struct btf_pipe *p = ctx; 15789af44bc5SAndrii Nakryiko int off; 15799af44bc5SAndrii Nakryiko 15809af44bc5SAndrii Nakryiko if (!*str_off) /* nothing to do for empty strings */ 15819af44bc5SAndrii Nakryiko return 0; 15829af44bc5SAndrii Nakryiko 15839af44bc5SAndrii Nakryiko off = btf__add_str(p->dst, btf__str_by_offset(p->src, *str_off)); 15849af44bc5SAndrii Nakryiko if (off < 0) 15859af44bc5SAndrii Nakryiko return off; 15869af44bc5SAndrii Nakryiko 15879af44bc5SAndrii Nakryiko *str_off = off; 15889af44bc5SAndrii Nakryiko return 0; 15899af44bc5SAndrii Nakryiko } 15909af44bc5SAndrii Nakryiko 15919af44bc5SAndrii Nakryiko int btf__add_type(struct btf *btf, const struct btf *src_btf, const struct btf_type *src_type) 15929af44bc5SAndrii Nakryiko { 15939af44bc5SAndrii Nakryiko struct btf_pipe p = { .src = src_btf, .dst = btf }; 15949af44bc5SAndrii Nakryiko struct btf_type *t; 15959af44bc5SAndrii Nakryiko int sz, err; 15969af44bc5SAndrii Nakryiko 15979af44bc5SAndrii Nakryiko sz = btf_type_size(src_type); 15989af44bc5SAndrii Nakryiko if (sz < 0) 1599e9fc3ce9SAndrii Nakryiko return libbpf_err(sz); 16009af44bc5SAndrii Nakryiko 16019af44bc5SAndrii Nakryiko /* deconstruct BTF, if necessary, and invalidate raw_data */ 16029af44bc5SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 1603e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 16049af44bc5SAndrii Nakryiko 16059af44bc5SAndrii Nakryiko t = btf_add_type_mem(btf, sz); 16069af44bc5SAndrii Nakryiko if (!t) 1607e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 16089af44bc5SAndrii Nakryiko 16099af44bc5SAndrii Nakryiko memcpy(t, src_type, sz); 16109af44bc5SAndrii Nakryiko 16119af44bc5SAndrii Nakryiko err = btf_type_visit_str_offs(t, btf_rewrite_str, &p); 16129af44bc5SAndrii Nakryiko if (err) 1613e9fc3ce9SAndrii Nakryiko return libbpf_err(err); 16149af44bc5SAndrii Nakryiko 16159af44bc5SAndrii Nakryiko return btf_commit_type(btf, sz); 16169af44bc5SAndrii Nakryiko } 16179af44bc5SAndrii Nakryiko 16187ca61121SAndrii Nakryiko static int btf_rewrite_type_ids(__u32 *type_id, void *ctx) 16197ca61121SAndrii Nakryiko { 16207ca61121SAndrii Nakryiko struct btf *btf = ctx; 16217ca61121SAndrii Nakryiko 16227ca61121SAndrii Nakryiko if (!*type_id) /* nothing to do for VOID references */ 16237ca61121SAndrii Nakryiko return 0; 16247ca61121SAndrii Nakryiko 16257ca61121SAndrii Nakryiko /* we haven't updated btf's type count yet, so 16267ca61121SAndrii Nakryiko * btf->start_id + btf->nr_types - 1 is the type ID offset we should 16277ca61121SAndrii Nakryiko * add to all newly added BTF types 16287ca61121SAndrii Nakryiko */ 16297ca61121SAndrii Nakryiko *type_id += btf->start_id + btf->nr_types - 1; 16307ca61121SAndrii Nakryiko return 0; 16317ca61121SAndrii Nakryiko } 16327ca61121SAndrii Nakryiko 16337ca61121SAndrii Nakryiko int btf__add_btf(struct btf *btf, const struct btf *src_btf) 16347ca61121SAndrii Nakryiko { 16357ca61121SAndrii Nakryiko struct btf_pipe p = { .src = src_btf, .dst = btf }; 16367ca61121SAndrii Nakryiko int data_sz, sz, cnt, i, err, old_strs_len; 16377ca61121SAndrii Nakryiko __u32 *off; 16387ca61121SAndrii Nakryiko void *t; 16397ca61121SAndrii Nakryiko 16407ca61121SAndrii Nakryiko /* appending split BTF isn't supported yet */ 16417ca61121SAndrii Nakryiko if (src_btf->base_btf) 16427ca61121SAndrii Nakryiko return libbpf_err(-ENOTSUP); 16437ca61121SAndrii Nakryiko 16447ca61121SAndrii Nakryiko /* deconstruct BTF, if necessary, and invalidate raw_data */ 16457ca61121SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 16467ca61121SAndrii Nakryiko return libbpf_err(-ENOMEM); 16477ca61121SAndrii Nakryiko 16487ca61121SAndrii Nakryiko /* remember original strings section size if we have to roll back 16497ca61121SAndrii Nakryiko * partial strings section changes 16507ca61121SAndrii Nakryiko */ 16517ca61121SAndrii Nakryiko old_strs_len = btf->hdr->str_len; 16527ca61121SAndrii Nakryiko 16537ca61121SAndrii Nakryiko data_sz = src_btf->hdr->type_len; 16547ca61121SAndrii Nakryiko cnt = btf__get_nr_types(src_btf); 16557ca61121SAndrii Nakryiko 16567ca61121SAndrii Nakryiko /* pre-allocate enough memory for new types */ 16577ca61121SAndrii Nakryiko t = btf_add_type_mem(btf, data_sz); 16587ca61121SAndrii Nakryiko if (!t) 16597ca61121SAndrii Nakryiko return libbpf_err(-ENOMEM); 16607ca61121SAndrii Nakryiko 16617ca61121SAndrii Nakryiko /* pre-allocate enough memory for type offset index for new types */ 16627ca61121SAndrii Nakryiko off = btf_add_type_offs_mem(btf, cnt); 16637ca61121SAndrii Nakryiko if (!off) 16647ca61121SAndrii Nakryiko return libbpf_err(-ENOMEM); 16657ca61121SAndrii Nakryiko 16667ca61121SAndrii Nakryiko /* bulk copy types data for all types from src_btf */ 16677ca61121SAndrii Nakryiko memcpy(t, src_btf->types_data, data_sz); 16687ca61121SAndrii Nakryiko 16697ca61121SAndrii Nakryiko for (i = 0; i < cnt; i++) { 16707ca61121SAndrii Nakryiko sz = btf_type_size(t); 16717ca61121SAndrii Nakryiko if (sz < 0) { 16727ca61121SAndrii Nakryiko /* unlikely, has to be corrupted src_btf */ 16737ca61121SAndrii Nakryiko err = sz; 16747ca61121SAndrii Nakryiko goto err_out; 16757ca61121SAndrii Nakryiko } 16767ca61121SAndrii Nakryiko 16777ca61121SAndrii Nakryiko /* fill out type ID to type offset mapping for lookups by type ID */ 16787ca61121SAndrii Nakryiko *off = t - btf->types_data; 16797ca61121SAndrii Nakryiko 16807ca61121SAndrii Nakryiko /* add, dedup, and remap strings referenced by this BTF type */ 16817ca61121SAndrii Nakryiko err = btf_type_visit_str_offs(t, btf_rewrite_str, &p); 16827ca61121SAndrii Nakryiko if (err) 16837ca61121SAndrii Nakryiko goto err_out; 16847ca61121SAndrii Nakryiko 16857ca61121SAndrii Nakryiko /* remap all type IDs referenced from this BTF type */ 16867ca61121SAndrii Nakryiko err = btf_type_visit_type_ids(t, btf_rewrite_type_ids, btf); 16877ca61121SAndrii Nakryiko if (err) 16887ca61121SAndrii Nakryiko goto err_out; 16897ca61121SAndrii Nakryiko 16907ca61121SAndrii Nakryiko /* go to next type data and type offset index entry */ 16917ca61121SAndrii Nakryiko t += sz; 16927ca61121SAndrii Nakryiko off++; 16937ca61121SAndrii Nakryiko } 16947ca61121SAndrii Nakryiko 16957ca61121SAndrii Nakryiko /* Up until now any of the copied type data was effectively invisible, 16967ca61121SAndrii Nakryiko * so if we exited early before this point due to error, BTF would be 16977ca61121SAndrii Nakryiko * effectively unmodified. There would be extra internal memory 16987ca61121SAndrii Nakryiko * pre-allocated, but it would not be available for querying. But now 16997ca61121SAndrii Nakryiko * that we've copied and rewritten all the data successfully, we can 17007ca61121SAndrii Nakryiko * update type count and various internal offsets and sizes to 17017ca61121SAndrii Nakryiko * "commit" the changes and made them visible to the outside world. 17027ca61121SAndrii Nakryiko */ 17037ca61121SAndrii Nakryiko btf->hdr->type_len += data_sz; 17047ca61121SAndrii Nakryiko btf->hdr->str_off += data_sz; 17057ca61121SAndrii Nakryiko btf->nr_types += cnt; 17067ca61121SAndrii Nakryiko 17077ca61121SAndrii Nakryiko /* return type ID of the first added BTF type */ 17087ca61121SAndrii Nakryiko return btf->start_id + btf->nr_types - cnt; 17097ca61121SAndrii Nakryiko err_out: 17107ca61121SAndrii Nakryiko /* zero out preallocated memory as if it was just allocated with 17117ca61121SAndrii Nakryiko * libbpf_add_mem() 17127ca61121SAndrii Nakryiko */ 17137ca61121SAndrii Nakryiko memset(btf->types_data + btf->hdr->type_len, 0, data_sz); 17147ca61121SAndrii Nakryiko memset(btf->strs_data + old_strs_len, 0, btf->hdr->str_len - old_strs_len); 17157ca61121SAndrii Nakryiko 17167ca61121SAndrii Nakryiko /* and now restore original strings section size; types data size 17177ca61121SAndrii Nakryiko * wasn't modified, so doesn't need restoring, see big comment above */ 17187ca61121SAndrii Nakryiko btf->hdr->str_len = old_strs_len; 17197ca61121SAndrii Nakryiko 17207ca61121SAndrii Nakryiko return libbpf_err(err); 17217ca61121SAndrii Nakryiko } 17227ca61121SAndrii Nakryiko 17234a3b33f8SAndrii Nakryiko /* 17244a3b33f8SAndrii Nakryiko * Append new BTF_KIND_INT type with: 17254a3b33f8SAndrii Nakryiko * - *name* - non-empty, non-NULL type name; 17264a3b33f8SAndrii Nakryiko * - *sz* - power-of-2 (1, 2, 4, ..) size of the type, in bytes; 17274a3b33f8SAndrii Nakryiko * - encoding is a combination of BTF_INT_SIGNED, BTF_INT_CHAR, BTF_INT_BOOL. 17284a3b33f8SAndrii Nakryiko * Returns: 17294a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 17304a3b33f8SAndrii Nakryiko * - <0, on error. 17314a3b33f8SAndrii Nakryiko */ 17324a3b33f8SAndrii Nakryiko int btf__add_int(struct btf *btf, const char *name, size_t byte_sz, int encoding) 17334a3b33f8SAndrii Nakryiko { 17344a3b33f8SAndrii Nakryiko struct btf_type *t; 1735c81ed6d8SAndrii Nakryiko int sz, name_off; 17364a3b33f8SAndrii Nakryiko 17374a3b33f8SAndrii Nakryiko /* non-empty name */ 17384a3b33f8SAndrii Nakryiko if (!name || !name[0]) 1739e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 17404a3b33f8SAndrii Nakryiko /* byte_sz must be power of 2 */ 17414a3b33f8SAndrii Nakryiko if (!byte_sz || (byte_sz & (byte_sz - 1)) || byte_sz > 16) 1742e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 17434a3b33f8SAndrii Nakryiko if (encoding & ~(BTF_INT_SIGNED | BTF_INT_CHAR | BTF_INT_BOOL)) 1744e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 17454a3b33f8SAndrii Nakryiko 17464a3b33f8SAndrii Nakryiko /* deconstruct BTF, if necessary, and invalidate raw_data */ 17474a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 1748e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 17494a3b33f8SAndrii Nakryiko 17504a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_type) + sizeof(int); 17514a3b33f8SAndrii Nakryiko t = btf_add_type_mem(btf, sz); 17524a3b33f8SAndrii Nakryiko if (!t) 1753e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 17544a3b33f8SAndrii Nakryiko 17554a3b33f8SAndrii Nakryiko /* if something goes wrong later, we might end up with an extra string, 17564a3b33f8SAndrii Nakryiko * but that shouldn't be a problem, because BTF can't be constructed 17574a3b33f8SAndrii Nakryiko * completely anyway and will most probably be just discarded 17584a3b33f8SAndrii Nakryiko */ 17594a3b33f8SAndrii Nakryiko name_off = btf__add_str(btf, name); 17604a3b33f8SAndrii Nakryiko if (name_off < 0) 17614a3b33f8SAndrii Nakryiko return name_off; 17624a3b33f8SAndrii Nakryiko 17634a3b33f8SAndrii Nakryiko t->name_off = name_off; 17644a3b33f8SAndrii Nakryiko t->info = btf_type_info(BTF_KIND_INT, 0, 0); 17654a3b33f8SAndrii Nakryiko t->size = byte_sz; 17664a3b33f8SAndrii Nakryiko /* set INT info, we don't allow setting legacy bit offset/size */ 17674a3b33f8SAndrii Nakryiko *(__u32 *)(t + 1) = (encoding << 24) | (byte_sz * 8); 17684a3b33f8SAndrii Nakryiko 1769c81ed6d8SAndrii Nakryiko return btf_commit_type(btf, sz); 17704a3b33f8SAndrii Nakryiko } 17714a3b33f8SAndrii Nakryiko 177222541a9eSIlya Leoshkevich /* 177322541a9eSIlya Leoshkevich * Append new BTF_KIND_FLOAT type with: 177422541a9eSIlya Leoshkevich * - *name* - non-empty, non-NULL type name; 177522541a9eSIlya Leoshkevich * - *sz* - size of the type, in bytes; 177622541a9eSIlya Leoshkevich * Returns: 177722541a9eSIlya Leoshkevich * - >0, type ID of newly added BTF type; 177822541a9eSIlya Leoshkevich * - <0, on error. 177922541a9eSIlya Leoshkevich */ 178022541a9eSIlya Leoshkevich int btf__add_float(struct btf *btf, const char *name, size_t byte_sz) 178122541a9eSIlya Leoshkevich { 178222541a9eSIlya Leoshkevich struct btf_type *t; 178322541a9eSIlya Leoshkevich int sz, name_off; 178422541a9eSIlya Leoshkevich 178522541a9eSIlya Leoshkevich /* non-empty name */ 178622541a9eSIlya Leoshkevich if (!name || !name[0]) 1787e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 178822541a9eSIlya Leoshkevich 178922541a9eSIlya Leoshkevich /* byte_sz must be one of the explicitly allowed values */ 179022541a9eSIlya Leoshkevich if (byte_sz != 2 && byte_sz != 4 && byte_sz != 8 && byte_sz != 12 && 179122541a9eSIlya Leoshkevich byte_sz != 16) 1792e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 179322541a9eSIlya Leoshkevich 179422541a9eSIlya Leoshkevich if (btf_ensure_modifiable(btf)) 1795e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 179622541a9eSIlya Leoshkevich 179722541a9eSIlya Leoshkevich sz = sizeof(struct btf_type); 179822541a9eSIlya Leoshkevich t = btf_add_type_mem(btf, sz); 179922541a9eSIlya Leoshkevich if (!t) 1800e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 180122541a9eSIlya Leoshkevich 180222541a9eSIlya Leoshkevich name_off = btf__add_str(btf, name); 180322541a9eSIlya Leoshkevich if (name_off < 0) 180422541a9eSIlya Leoshkevich return name_off; 180522541a9eSIlya Leoshkevich 180622541a9eSIlya Leoshkevich t->name_off = name_off; 180722541a9eSIlya Leoshkevich t->info = btf_type_info(BTF_KIND_FLOAT, 0, 0); 180822541a9eSIlya Leoshkevich t->size = byte_sz; 180922541a9eSIlya Leoshkevich 181022541a9eSIlya Leoshkevich return btf_commit_type(btf, sz); 181122541a9eSIlya Leoshkevich } 181222541a9eSIlya Leoshkevich 18134a3b33f8SAndrii Nakryiko /* it's completely legal to append BTF types with type IDs pointing forward to 18144a3b33f8SAndrii Nakryiko * types that haven't been appended yet, so we only make sure that id looks 18154a3b33f8SAndrii Nakryiko * sane, we can't guarantee that ID will always be valid 18164a3b33f8SAndrii Nakryiko */ 18174a3b33f8SAndrii Nakryiko static int validate_type_id(int id) 18184a3b33f8SAndrii Nakryiko { 18194a3b33f8SAndrii Nakryiko if (id < 0 || id > BTF_MAX_NR_TYPES) 18204a3b33f8SAndrii Nakryiko return -EINVAL; 18214a3b33f8SAndrii Nakryiko return 0; 18224a3b33f8SAndrii Nakryiko } 18234a3b33f8SAndrii Nakryiko 18244a3b33f8SAndrii Nakryiko /* generic append function for PTR, TYPEDEF, CONST/VOLATILE/RESTRICT */ 18254a3b33f8SAndrii Nakryiko static int btf_add_ref_kind(struct btf *btf, int kind, const char *name, int ref_type_id) 18264a3b33f8SAndrii Nakryiko { 18274a3b33f8SAndrii Nakryiko struct btf_type *t; 1828c81ed6d8SAndrii Nakryiko int sz, name_off = 0; 18294a3b33f8SAndrii Nakryiko 18304a3b33f8SAndrii Nakryiko if (validate_type_id(ref_type_id)) 1831e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 18324a3b33f8SAndrii Nakryiko 18334a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 1834e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 18354a3b33f8SAndrii Nakryiko 18364a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_type); 18374a3b33f8SAndrii Nakryiko t = btf_add_type_mem(btf, sz); 18384a3b33f8SAndrii Nakryiko if (!t) 1839e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 18404a3b33f8SAndrii Nakryiko 18414a3b33f8SAndrii Nakryiko if (name && name[0]) { 18424a3b33f8SAndrii Nakryiko name_off = btf__add_str(btf, name); 18434a3b33f8SAndrii Nakryiko if (name_off < 0) 18444a3b33f8SAndrii Nakryiko return name_off; 18454a3b33f8SAndrii Nakryiko } 18464a3b33f8SAndrii Nakryiko 18474a3b33f8SAndrii Nakryiko t->name_off = name_off; 18484a3b33f8SAndrii Nakryiko t->info = btf_type_info(kind, 0, 0); 18494a3b33f8SAndrii Nakryiko t->type = ref_type_id; 18504a3b33f8SAndrii Nakryiko 1851c81ed6d8SAndrii Nakryiko return btf_commit_type(btf, sz); 18524a3b33f8SAndrii Nakryiko } 18534a3b33f8SAndrii Nakryiko 18544a3b33f8SAndrii Nakryiko /* 18554a3b33f8SAndrii Nakryiko * Append new BTF_KIND_PTR type with: 18564a3b33f8SAndrii Nakryiko * - *ref_type_id* - referenced type ID, it might not exist yet; 18574a3b33f8SAndrii Nakryiko * Returns: 18584a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 18594a3b33f8SAndrii Nakryiko * - <0, on error. 18604a3b33f8SAndrii Nakryiko */ 18614a3b33f8SAndrii Nakryiko int btf__add_ptr(struct btf *btf, int ref_type_id) 18624a3b33f8SAndrii Nakryiko { 18634a3b33f8SAndrii Nakryiko return btf_add_ref_kind(btf, BTF_KIND_PTR, NULL, ref_type_id); 18644a3b33f8SAndrii Nakryiko } 18654a3b33f8SAndrii Nakryiko 18664a3b33f8SAndrii Nakryiko /* 18674a3b33f8SAndrii Nakryiko * Append new BTF_KIND_ARRAY type with: 18684a3b33f8SAndrii Nakryiko * - *index_type_id* - type ID of the type describing array index; 18694a3b33f8SAndrii Nakryiko * - *elem_type_id* - type ID of the type describing array element; 18704a3b33f8SAndrii Nakryiko * - *nr_elems* - the size of the array; 18714a3b33f8SAndrii Nakryiko * Returns: 18724a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 18734a3b33f8SAndrii Nakryiko * - <0, on error. 18744a3b33f8SAndrii Nakryiko */ 18754a3b33f8SAndrii Nakryiko int btf__add_array(struct btf *btf, int index_type_id, int elem_type_id, __u32 nr_elems) 18764a3b33f8SAndrii Nakryiko { 18774a3b33f8SAndrii Nakryiko struct btf_type *t; 18784a3b33f8SAndrii Nakryiko struct btf_array *a; 1879c81ed6d8SAndrii Nakryiko int sz; 18804a3b33f8SAndrii Nakryiko 18814a3b33f8SAndrii Nakryiko if (validate_type_id(index_type_id) || validate_type_id(elem_type_id)) 1882e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 18834a3b33f8SAndrii Nakryiko 18844a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 1885e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 18864a3b33f8SAndrii Nakryiko 18874a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_type) + sizeof(struct btf_array); 18884a3b33f8SAndrii Nakryiko t = btf_add_type_mem(btf, sz); 18894a3b33f8SAndrii Nakryiko if (!t) 1890e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 18914a3b33f8SAndrii Nakryiko 18924a3b33f8SAndrii Nakryiko t->name_off = 0; 18934a3b33f8SAndrii Nakryiko t->info = btf_type_info(BTF_KIND_ARRAY, 0, 0); 18944a3b33f8SAndrii Nakryiko t->size = 0; 18954a3b33f8SAndrii Nakryiko 18964a3b33f8SAndrii Nakryiko a = btf_array(t); 18974a3b33f8SAndrii Nakryiko a->type = elem_type_id; 18984a3b33f8SAndrii Nakryiko a->index_type = index_type_id; 18994a3b33f8SAndrii Nakryiko a->nelems = nr_elems; 19004a3b33f8SAndrii Nakryiko 1901c81ed6d8SAndrii Nakryiko return btf_commit_type(btf, sz); 19024a3b33f8SAndrii Nakryiko } 19034a3b33f8SAndrii Nakryiko 19044a3b33f8SAndrii Nakryiko /* generic STRUCT/UNION append function */ 19054a3b33f8SAndrii Nakryiko static int btf_add_composite(struct btf *btf, int kind, const char *name, __u32 bytes_sz) 19064a3b33f8SAndrii Nakryiko { 19074a3b33f8SAndrii Nakryiko struct btf_type *t; 1908c81ed6d8SAndrii Nakryiko int sz, name_off = 0; 19094a3b33f8SAndrii Nakryiko 19104a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 1911e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 19124a3b33f8SAndrii Nakryiko 19134a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_type); 19144a3b33f8SAndrii Nakryiko t = btf_add_type_mem(btf, sz); 19154a3b33f8SAndrii Nakryiko if (!t) 1916e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 19174a3b33f8SAndrii Nakryiko 19184a3b33f8SAndrii Nakryiko if (name && name[0]) { 19194a3b33f8SAndrii Nakryiko name_off = btf__add_str(btf, name); 19204a3b33f8SAndrii Nakryiko if (name_off < 0) 19214a3b33f8SAndrii Nakryiko return name_off; 19224a3b33f8SAndrii Nakryiko } 19234a3b33f8SAndrii Nakryiko 19244a3b33f8SAndrii Nakryiko /* start out with vlen=0 and no kflag; this will be adjusted when 19254a3b33f8SAndrii Nakryiko * adding each member 19264a3b33f8SAndrii Nakryiko */ 19274a3b33f8SAndrii Nakryiko t->name_off = name_off; 19284a3b33f8SAndrii Nakryiko t->info = btf_type_info(kind, 0, 0); 19294a3b33f8SAndrii Nakryiko t->size = bytes_sz; 19304a3b33f8SAndrii Nakryiko 1931c81ed6d8SAndrii Nakryiko return btf_commit_type(btf, sz); 19324a3b33f8SAndrii Nakryiko } 19334a3b33f8SAndrii Nakryiko 19344a3b33f8SAndrii Nakryiko /* 19354a3b33f8SAndrii Nakryiko * Append new BTF_KIND_STRUCT type with: 19364a3b33f8SAndrii Nakryiko * - *name* - name of the struct, can be NULL or empty for anonymous structs; 19374a3b33f8SAndrii Nakryiko * - *byte_sz* - size of the struct, in bytes; 19384a3b33f8SAndrii Nakryiko * 19394a3b33f8SAndrii Nakryiko * Struct initially has no fields in it. Fields can be added by 19404a3b33f8SAndrii Nakryiko * btf__add_field() right after btf__add_struct() succeeds. 19414a3b33f8SAndrii Nakryiko * 19424a3b33f8SAndrii Nakryiko * Returns: 19434a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 19444a3b33f8SAndrii Nakryiko * - <0, on error. 19454a3b33f8SAndrii Nakryiko */ 19464a3b33f8SAndrii Nakryiko int btf__add_struct(struct btf *btf, const char *name, __u32 byte_sz) 19474a3b33f8SAndrii Nakryiko { 19484a3b33f8SAndrii Nakryiko return btf_add_composite(btf, BTF_KIND_STRUCT, name, byte_sz); 19494a3b33f8SAndrii Nakryiko } 19504a3b33f8SAndrii Nakryiko 19514a3b33f8SAndrii Nakryiko /* 19524a3b33f8SAndrii Nakryiko * Append new BTF_KIND_UNION type with: 19534a3b33f8SAndrii Nakryiko * - *name* - name of the union, can be NULL or empty for anonymous union; 19544a3b33f8SAndrii Nakryiko * - *byte_sz* - size of the union, in bytes; 19554a3b33f8SAndrii Nakryiko * 19564a3b33f8SAndrii Nakryiko * Union initially has no fields in it. Fields can be added by 19574a3b33f8SAndrii Nakryiko * btf__add_field() right after btf__add_union() succeeds. All fields 19584a3b33f8SAndrii Nakryiko * should have *bit_offset* of 0. 19594a3b33f8SAndrii Nakryiko * 19604a3b33f8SAndrii Nakryiko * Returns: 19614a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 19624a3b33f8SAndrii Nakryiko * - <0, on error. 19634a3b33f8SAndrii Nakryiko */ 19644a3b33f8SAndrii Nakryiko int btf__add_union(struct btf *btf, const char *name, __u32 byte_sz) 19654a3b33f8SAndrii Nakryiko { 19664a3b33f8SAndrii Nakryiko return btf_add_composite(btf, BTF_KIND_UNION, name, byte_sz); 19674a3b33f8SAndrii Nakryiko } 19684a3b33f8SAndrii Nakryiko 1969c81ed6d8SAndrii Nakryiko static struct btf_type *btf_last_type(struct btf *btf) 1970c81ed6d8SAndrii Nakryiko { 1971c81ed6d8SAndrii Nakryiko return btf_type_by_id(btf, btf__get_nr_types(btf)); 1972c81ed6d8SAndrii Nakryiko } 1973c81ed6d8SAndrii Nakryiko 19744a3b33f8SAndrii Nakryiko /* 19754a3b33f8SAndrii Nakryiko * Append new field for the current STRUCT/UNION type with: 19764a3b33f8SAndrii Nakryiko * - *name* - name of the field, can be NULL or empty for anonymous field; 19774a3b33f8SAndrii Nakryiko * - *type_id* - type ID for the type describing field type; 19784a3b33f8SAndrii Nakryiko * - *bit_offset* - bit offset of the start of the field within struct/union; 19794a3b33f8SAndrii Nakryiko * - *bit_size* - bit size of a bitfield, 0 for non-bitfield fields; 19804a3b33f8SAndrii Nakryiko * Returns: 19814a3b33f8SAndrii Nakryiko * - 0, on success; 19824a3b33f8SAndrii Nakryiko * - <0, on error. 19834a3b33f8SAndrii Nakryiko */ 19844a3b33f8SAndrii Nakryiko int btf__add_field(struct btf *btf, const char *name, int type_id, 19854a3b33f8SAndrii Nakryiko __u32 bit_offset, __u32 bit_size) 19864a3b33f8SAndrii Nakryiko { 19874a3b33f8SAndrii Nakryiko struct btf_type *t; 19884a3b33f8SAndrii Nakryiko struct btf_member *m; 19894a3b33f8SAndrii Nakryiko bool is_bitfield; 19904a3b33f8SAndrii Nakryiko int sz, name_off = 0; 19914a3b33f8SAndrii Nakryiko 19924a3b33f8SAndrii Nakryiko /* last type should be union/struct */ 19934a3b33f8SAndrii Nakryiko if (btf->nr_types == 0) 1994e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 1995c81ed6d8SAndrii Nakryiko t = btf_last_type(btf); 19964a3b33f8SAndrii Nakryiko if (!btf_is_composite(t)) 1997e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 19984a3b33f8SAndrii Nakryiko 19994a3b33f8SAndrii Nakryiko if (validate_type_id(type_id)) 2000e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 20014a3b33f8SAndrii Nakryiko /* best-effort bit field offset/size enforcement */ 20024a3b33f8SAndrii Nakryiko is_bitfield = bit_size || (bit_offset % 8 != 0); 20034a3b33f8SAndrii Nakryiko if (is_bitfield && (bit_size == 0 || bit_size > 255 || bit_offset > 0xffffff)) 2004e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 20054a3b33f8SAndrii Nakryiko 20064a3b33f8SAndrii Nakryiko /* only offset 0 is allowed for unions */ 20074a3b33f8SAndrii Nakryiko if (btf_is_union(t) && bit_offset) 2008e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 20094a3b33f8SAndrii Nakryiko 20104a3b33f8SAndrii Nakryiko /* decompose and invalidate raw data */ 20114a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 2012e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 20134a3b33f8SAndrii Nakryiko 20144a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_member); 20154a3b33f8SAndrii Nakryiko m = btf_add_type_mem(btf, sz); 20164a3b33f8SAndrii Nakryiko if (!m) 2017e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 20184a3b33f8SAndrii Nakryiko 20194a3b33f8SAndrii Nakryiko if (name && name[0]) { 20204a3b33f8SAndrii Nakryiko name_off = btf__add_str(btf, name); 20214a3b33f8SAndrii Nakryiko if (name_off < 0) 20224a3b33f8SAndrii Nakryiko return name_off; 20234a3b33f8SAndrii Nakryiko } 20244a3b33f8SAndrii Nakryiko 20254a3b33f8SAndrii Nakryiko m->name_off = name_off; 20264a3b33f8SAndrii Nakryiko m->type = type_id; 20274a3b33f8SAndrii Nakryiko m->offset = bit_offset | (bit_size << 24); 20284a3b33f8SAndrii Nakryiko 20294a3b33f8SAndrii Nakryiko /* btf_add_type_mem can invalidate t pointer */ 2030c81ed6d8SAndrii Nakryiko t = btf_last_type(btf); 20314a3b33f8SAndrii Nakryiko /* update parent type's vlen and kflag */ 20324a3b33f8SAndrii Nakryiko t->info = btf_type_info(btf_kind(t), btf_vlen(t) + 1, is_bitfield || btf_kflag(t)); 20334a3b33f8SAndrii Nakryiko 20344a3b33f8SAndrii Nakryiko btf->hdr->type_len += sz; 20354a3b33f8SAndrii Nakryiko btf->hdr->str_off += sz; 20364a3b33f8SAndrii Nakryiko return 0; 20374a3b33f8SAndrii Nakryiko } 20384a3b33f8SAndrii Nakryiko 20394a3b33f8SAndrii Nakryiko /* 20404a3b33f8SAndrii Nakryiko * Append new BTF_KIND_ENUM type with: 20414a3b33f8SAndrii Nakryiko * - *name* - name of the enum, can be NULL or empty for anonymous enums; 20424a3b33f8SAndrii Nakryiko * - *byte_sz* - size of the enum, in bytes. 20434a3b33f8SAndrii Nakryiko * 20444a3b33f8SAndrii Nakryiko * Enum initially has no enum values in it (and corresponds to enum forward 20454a3b33f8SAndrii Nakryiko * declaration). Enumerator values can be added by btf__add_enum_value() 20464a3b33f8SAndrii Nakryiko * immediately after btf__add_enum() succeeds. 20474a3b33f8SAndrii Nakryiko * 20484a3b33f8SAndrii Nakryiko * Returns: 20494a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 20504a3b33f8SAndrii Nakryiko * - <0, on error. 20514a3b33f8SAndrii Nakryiko */ 20524a3b33f8SAndrii Nakryiko int btf__add_enum(struct btf *btf, const char *name, __u32 byte_sz) 20534a3b33f8SAndrii Nakryiko { 20544a3b33f8SAndrii Nakryiko struct btf_type *t; 2055c81ed6d8SAndrii Nakryiko int sz, name_off = 0; 20564a3b33f8SAndrii Nakryiko 20574a3b33f8SAndrii Nakryiko /* byte_sz must be power of 2 */ 20584a3b33f8SAndrii Nakryiko if (!byte_sz || (byte_sz & (byte_sz - 1)) || byte_sz > 8) 2059e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 20604a3b33f8SAndrii Nakryiko 20614a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 2062e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 20634a3b33f8SAndrii Nakryiko 20644a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_type); 20654a3b33f8SAndrii Nakryiko t = btf_add_type_mem(btf, sz); 20664a3b33f8SAndrii Nakryiko if (!t) 2067e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 20684a3b33f8SAndrii Nakryiko 20694a3b33f8SAndrii Nakryiko if (name && name[0]) { 20704a3b33f8SAndrii Nakryiko name_off = btf__add_str(btf, name); 20714a3b33f8SAndrii Nakryiko if (name_off < 0) 20724a3b33f8SAndrii Nakryiko return name_off; 20734a3b33f8SAndrii Nakryiko } 20744a3b33f8SAndrii Nakryiko 20754a3b33f8SAndrii Nakryiko /* start out with vlen=0; it will be adjusted when adding enum values */ 20764a3b33f8SAndrii Nakryiko t->name_off = name_off; 20774a3b33f8SAndrii Nakryiko t->info = btf_type_info(BTF_KIND_ENUM, 0, 0); 20784a3b33f8SAndrii Nakryiko t->size = byte_sz; 20794a3b33f8SAndrii Nakryiko 2080c81ed6d8SAndrii Nakryiko return btf_commit_type(btf, sz); 20814a3b33f8SAndrii Nakryiko } 20824a3b33f8SAndrii Nakryiko 20834a3b33f8SAndrii Nakryiko /* 20844a3b33f8SAndrii Nakryiko * Append new enum value for the current ENUM type with: 20854a3b33f8SAndrii Nakryiko * - *name* - name of the enumerator value, can't be NULL or empty; 20864a3b33f8SAndrii Nakryiko * - *value* - integer value corresponding to enum value *name*; 20874a3b33f8SAndrii Nakryiko * Returns: 20884a3b33f8SAndrii Nakryiko * - 0, on success; 20894a3b33f8SAndrii Nakryiko * - <0, on error. 20904a3b33f8SAndrii Nakryiko */ 20914a3b33f8SAndrii Nakryiko int btf__add_enum_value(struct btf *btf, const char *name, __s64 value) 20924a3b33f8SAndrii Nakryiko { 20934a3b33f8SAndrii Nakryiko struct btf_type *t; 20944a3b33f8SAndrii Nakryiko struct btf_enum *v; 20954a3b33f8SAndrii Nakryiko int sz, name_off; 20964a3b33f8SAndrii Nakryiko 20974a3b33f8SAndrii Nakryiko /* last type should be BTF_KIND_ENUM */ 20984a3b33f8SAndrii Nakryiko if (btf->nr_types == 0) 2099e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 2100c81ed6d8SAndrii Nakryiko t = btf_last_type(btf); 21014a3b33f8SAndrii Nakryiko if (!btf_is_enum(t)) 2102e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 21034a3b33f8SAndrii Nakryiko 21044a3b33f8SAndrii Nakryiko /* non-empty name */ 21054a3b33f8SAndrii Nakryiko if (!name || !name[0]) 2106e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 21074a3b33f8SAndrii Nakryiko if (value < INT_MIN || value > UINT_MAX) 2108e9fc3ce9SAndrii Nakryiko return libbpf_err(-E2BIG); 21094a3b33f8SAndrii Nakryiko 21104a3b33f8SAndrii Nakryiko /* decompose and invalidate raw data */ 21114a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 2112e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 21134a3b33f8SAndrii Nakryiko 21144a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_enum); 21154a3b33f8SAndrii Nakryiko v = btf_add_type_mem(btf, sz); 21164a3b33f8SAndrii Nakryiko if (!v) 2117e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 21184a3b33f8SAndrii Nakryiko 21194a3b33f8SAndrii Nakryiko name_off = btf__add_str(btf, name); 21204a3b33f8SAndrii Nakryiko if (name_off < 0) 21214a3b33f8SAndrii Nakryiko return name_off; 21224a3b33f8SAndrii Nakryiko 21234a3b33f8SAndrii Nakryiko v->name_off = name_off; 21244a3b33f8SAndrii Nakryiko v->val = value; 21254a3b33f8SAndrii Nakryiko 21264a3b33f8SAndrii Nakryiko /* update parent type's vlen */ 2127c81ed6d8SAndrii Nakryiko t = btf_last_type(btf); 21284a3b33f8SAndrii Nakryiko btf_type_inc_vlen(t); 21294a3b33f8SAndrii Nakryiko 21304a3b33f8SAndrii Nakryiko btf->hdr->type_len += sz; 21314a3b33f8SAndrii Nakryiko btf->hdr->str_off += sz; 21324a3b33f8SAndrii Nakryiko return 0; 21334a3b33f8SAndrii Nakryiko } 21344a3b33f8SAndrii Nakryiko 21354a3b33f8SAndrii Nakryiko /* 21364a3b33f8SAndrii Nakryiko * Append new BTF_KIND_FWD type with: 21374a3b33f8SAndrii Nakryiko * - *name*, non-empty/non-NULL name; 21384a3b33f8SAndrii Nakryiko * - *fwd_kind*, kind of forward declaration, one of BTF_FWD_STRUCT, 21394a3b33f8SAndrii Nakryiko * BTF_FWD_UNION, or BTF_FWD_ENUM; 21404a3b33f8SAndrii Nakryiko * Returns: 21414a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 21424a3b33f8SAndrii Nakryiko * - <0, on error. 21434a3b33f8SAndrii Nakryiko */ 21444a3b33f8SAndrii Nakryiko int btf__add_fwd(struct btf *btf, const char *name, enum btf_fwd_kind fwd_kind) 21454a3b33f8SAndrii Nakryiko { 21464a3b33f8SAndrii Nakryiko if (!name || !name[0]) 2147e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 21484a3b33f8SAndrii Nakryiko 21494a3b33f8SAndrii Nakryiko switch (fwd_kind) { 21504a3b33f8SAndrii Nakryiko case BTF_FWD_STRUCT: 21514a3b33f8SAndrii Nakryiko case BTF_FWD_UNION: { 21524a3b33f8SAndrii Nakryiko struct btf_type *t; 21534a3b33f8SAndrii Nakryiko int id; 21544a3b33f8SAndrii Nakryiko 21554a3b33f8SAndrii Nakryiko id = btf_add_ref_kind(btf, BTF_KIND_FWD, name, 0); 21564a3b33f8SAndrii Nakryiko if (id <= 0) 21574a3b33f8SAndrii Nakryiko return id; 21584a3b33f8SAndrii Nakryiko t = btf_type_by_id(btf, id); 21594a3b33f8SAndrii Nakryiko t->info = btf_type_info(BTF_KIND_FWD, 0, fwd_kind == BTF_FWD_UNION); 21604a3b33f8SAndrii Nakryiko return id; 21614a3b33f8SAndrii Nakryiko } 21624a3b33f8SAndrii Nakryiko case BTF_FWD_ENUM: 21634a3b33f8SAndrii Nakryiko /* enum forward in BTF currently is just an enum with no enum 21644a3b33f8SAndrii Nakryiko * values; we also assume a standard 4-byte size for it 21654a3b33f8SAndrii Nakryiko */ 21664a3b33f8SAndrii Nakryiko return btf__add_enum(btf, name, sizeof(int)); 21674a3b33f8SAndrii Nakryiko default: 2168e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 21694a3b33f8SAndrii Nakryiko } 21704a3b33f8SAndrii Nakryiko } 21714a3b33f8SAndrii Nakryiko 21724a3b33f8SAndrii Nakryiko /* 21734a3b33f8SAndrii Nakryiko * Append new BTF_KING_TYPEDEF type with: 21744a3b33f8SAndrii Nakryiko * - *name*, non-empty/non-NULL name; 21754a3b33f8SAndrii Nakryiko * - *ref_type_id* - referenced type ID, it might not exist yet; 21764a3b33f8SAndrii Nakryiko * Returns: 21774a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 21784a3b33f8SAndrii Nakryiko * - <0, on error. 21794a3b33f8SAndrii Nakryiko */ 21804a3b33f8SAndrii Nakryiko int btf__add_typedef(struct btf *btf, const char *name, int ref_type_id) 21814a3b33f8SAndrii Nakryiko { 21824a3b33f8SAndrii Nakryiko if (!name || !name[0]) 2183e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 21844a3b33f8SAndrii Nakryiko 21854a3b33f8SAndrii Nakryiko return btf_add_ref_kind(btf, BTF_KIND_TYPEDEF, name, ref_type_id); 21864a3b33f8SAndrii Nakryiko } 21874a3b33f8SAndrii Nakryiko 21884a3b33f8SAndrii Nakryiko /* 21894a3b33f8SAndrii Nakryiko * Append new BTF_KIND_VOLATILE type with: 21904a3b33f8SAndrii Nakryiko * - *ref_type_id* - referenced type ID, it might not exist yet; 21914a3b33f8SAndrii Nakryiko * Returns: 21924a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 21934a3b33f8SAndrii Nakryiko * - <0, on error. 21944a3b33f8SAndrii Nakryiko */ 21954a3b33f8SAndrii Nakryiko int btf__add_volatile(struct btf *btf, int ref_type_id) 21964a3b33f8SAndrii Nakryiko { 21974a3b33f8SAndrii Nakryiko return btf_add_ref_kind(btf, BTF_KIND_VOLATILE, NULL, ref_type_id); 21984a3b33f8SAndrii Nakryiko } 21994a3b33f8SAndrii Nakryiko 22004a3b33f8SAndrii Nakryiko /* 22014a3b33f8SAndrii Nakryiko * Append new BTF_KIND_CONST type with: 22024a3b33f8SAndrii Nakryiko * - *ref_type_id* - referenced type ID, it might not exist yet; 22034a3b33f8SAndrii Nakryiko * Returns: 22044a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 22054a3b33f8SAndrii Nakryiko * - <0, on error. 22064a3b33f8SAndrii Nakryiko */ 22074a3b33f8SAndrii Nakryiko int btf__add_const(struct btf *btf, int ref_type_id) 22084a3b33f8SAndrii Nakryiko { 22094a3b33f8SAndrii Nakryiko return btf_add_ref_kind(btf, BTF_KIND_CONST, NULL, ref_type_id); 22104a3b33f8SAndrii Nakryiko } 22114a3b33f8SAndrii Nakryiko 22124a3b33f8SAndrii Nakryiko /* 22134a3b33f8SAndrii Nakryiko * Append new BTF_KIND_RESTRICT type with: 22144a3b33f8SAndrii Nakryiko * - *ref_type_id* - referenced type ID, it might not exist yet; 22154a3b33f8SAndrii Nakryiko * Returns: 22164a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 22174a3b33f8SAndrii Nakryiko * - <0, on error. 22184a3b33f8SAndrii Nakryiko */ 22194a3b33f8SAndrii Nakryiko int btf__add_restrict(struct btf *btf, int ref_type_id) 22204a3b33f8SAndrii Nakryiko { 22214a3b33f8SAndrii Nakryiko return btf_add_ref_kind(btf, BTF_KIND_RESTRICT, NULL, ref_type_id); 22224a3b33f8SAndrii Nakryiko } 22234a3b33f8SAndrii Nakryiko 22244a3b33f8SAndrii Nakryiko /* 22254a3b33f8SAndrii Nakryiko * Append new BTF_KIND_FUNC type with: 22264a3b33f8SAndrii Nakryiko * - *name*, non-empty/non-NULL name; 22274a3b33f8SAndrii Nakryiko * - *proto_type_id* - FUNC_PROTO's type ID, it might not exist yet; 22284a3b33f8SAndrii Nakryiko * Returns: 22294a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 22304a3b33f8SAndrii Nakryiko * - <0, on error. 22314a3b33f8SAndrii Nakryiko */ 22324a3b33f8SAndrii Nakryiko int btf__add_func(struct btf *btf, const char *name, 22334a3b33f8SAndrii Nakryiko enum btf_func_linkage linkage, int proto_type_id) 22344a3b33f8SAndrii Nakryiko { 22354a3b33f8SAndrii Nakryiko int id; 22364a3b33f8SAndrii Nakryiko 22374a3b33f8SAndrii Nakryiko if (!name || !name[0]) 2238e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 22394a3b33f8SAndrii Nakryiko if (linkage != BTF_FUNC_STATIC && linkage != BTF_FUNC_GLOBAL && 22404a3b33f8SAndrii Nakryiko linkage != BTF_FUNC_EXTERN) 2241e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 22424a3b33f8SAndrii Nakryiko 22434a3b33f8SAndrii Nakryiko id = btf_add_ref_kind(btf, BTF_KIND_FUNC, name, proto_type_id); 22444a3b33f8SAndrii Nakryiko if (id > 0) { 22454a3b33f8SAndrii Nakryiko struct btf_type *t = btf_type_by_id(btf, id); 22464a3b33f8SAndrii Nakryiko 22474a3b33f8SAndrii Nakryiko t->info = btf_type_info(BTF_KIND_FUNC, linkage, 0); 22484a3b33f8SAndrii Nakryiko } 2249e9fc3ce9SAndrii Nakryiko return libbpf_err(id); 22504a3b33f8SAndrii Nakryiko } 22514a3b33f8SAndrii Nakryiko 22524a3b33f8SAndrii Nakryiko /* 22534a3b33f8SAndrii Nakryiko * Append new BTF_KIND_FUNC_PROTO with: 22544a3b33f8SAndrii Nakryiko * - *ret_type_id* - type ID for return result of a function. 22554a3b33f8SAndrii Nakryiko * 22564a3b33f8SAndrii Nakryiko * Function prototype initially has no arguments, but they can be added by 22574a3b33f8SAndrii Nakryiko * btf__add_func_param() one by one, immediately after 22584a3b33f8SAndrii Nakryiko * btf__add_func_proto() succeeded. 22594a3b33f8SAndrii Nakryiko * 22604a3b33f8SAndrii Nakryiko * Returns: 22614a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 22624a3b33f8SAndrii Nakryiko * - <0, on error. 22634a3b33f8SAndrii Nakryiko */ 22644a3b33f8SAndrii Nakryiko int btf__add_func_proto(struct btf *btf, int ret_type_id) 22654a3b33f8SAndrii Nakryiko { 22664a3b33f8SAndrii Nakryiko struct btf_type *t; 2267c81ed6d8SAndrii Nakryiko int sz; 22684a3b33f8SAndrii Nakryiko 22694a3b33f8SAndrii Nakryiko if (validate_type_id(ret_type_id)) 2270e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 22714a3b33f8SAndrii Nakryiko 22724a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 2273e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 22744a3b33f8SAndrii Nakryiko 22754a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_type); 22764a3b33f8SAndrii Nakryiko t = btf_add_type_mem(btf, sz); 22774a3b33f8SAndrii Nakryiko if (!t) 2278e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 22794a3b33f8SAndrii Nakryiko 22804a3b33f8SAndrii Nakryiko /* start out with vlen=0; this will be adjusted when adding enum 22814a3b33f8SAndrii Nakryiko * values, if necessary 22824a3b33f8SAndrii Nakryiko */ 22834a3b33f8SAndrii Nakryiko t->name_off = 0; 22844a3b33f8SAndrii Nakryiko t->info = btf_type_info(BTF_KIND_FUNC_PROTO, 0, 0); 22854a3b33f8SAndrii Nakryiko t->type = ret_type_id; 22864a3b33f8SAndrii Nakryiko 2287c81ed6d8SAndrii Nakryiko return btf_commit_type(btf, sz); 22884a3b33f8SAndrii Nakryiko } 22894a3b33f8SAndrii Nakryiko 22904a3b33f8SAndrii Nakryiko /* 22914a3b33f8SAndrii Nakryiko * Append new function parameter for current FUNC_PROTO type with: 22924a3b33f8SAndrii Nakryiko * - *name* - parameter name, can be NULL or empty; 22934a3b33f8SAndrii Nakryiko * - *type_id* - type ID describing the type of the parameter. 22944a3b33f8SAndrii Nakryiko * Returns: 22954a3b33f8SAndrii Nakryiko * - 0, on success; 22964a3b33f8SAndrii Nakryiko * - <0, on error. 22974a3b33f8SAndrii Nakryiko */ 22984a3b33f8SAndrii Nakryiko int btf__add_func_param(struct btf *btf, const char *name, int type_id) 22994a3b33f8SAndrii Nakryiko { 23004a3b33f8SAndrii Nakryiko struct btf_type *t; 23014a3b33f8SAndrii Nakryiko struct btf_param *p; 23024a3b33f8SAndrii Nakryiko int sz, name_off = 0; 23034a3b33f8SAndrii Nakryiko 23044a3b33f8SAndrii Nakryiko if (validate_type_id(type_id)) 2305e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 23064a3b33f8SAndrii Nakryiko 23074a3b33f8SAndrii Nakryiko /* last type should be BTF_KIND_FUNC_PROTO */ 23084a3b33f8SAndrii Nakryiko if (btf->nr_types == 0) 2309e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 2310c81ed6d8SAndrii Nakryiko t = btf_last_type(btf); 23114a3b33f8SAndrii Nakryiko if (!btf_is_func_proto(t)) 2312e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 23134a3b33f8SAndrii Nakryiko 23144a3b33f8SAndrii Nakryiko /* decompose and invalidate raw data */ 23154a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 2316e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 23174a3b33f8SAndrii Nakryiko 23184a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_param); 23194a3b33f8SAndrii Nakryiko p = btf_add_type_mem(btf, sz); 23204a3b33f8SAndrii Nakryiko if (!p) 2321e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 23224a3b33f8SAndrii Nakryiko 23234a3b33f8SAndrii Nakryiko if (name && name[0]) { 23244a3b33f8SAndrii Nakryiko name_off = btf__add_str(btf, name); 23254a3b33f8SAndrii Nakryiko if (name_off < 0) 23264a3b33f8SAndrii Nakryiko return name_off; 23274a3b33f8SAndrii Nakryiko } 23284a3b33f8SAndrii Nakryiko 23294a3b33f8SAndrii Nakryiko p->name_off = name_off; 23304a3b33f8SAndrii Nakryiko p->type = type_id; 23314a3b33f8SAndrii Nakryiko 23324a3b33f8SAndrii Nakryiko /* update parent type's vlen */ 2333c81ed6d8SAndrii Nakryiko t = btf_last_type(btf); 23344a3b33f8SAndrii Nakryiko btf_type_inc_vlen(t); 23354a3b33f8SAndrii Nakryiko 23364a3b33f8SAndrii Nakryiko btf->hdr->type_len += sz; 23374a3b33f8SAndrii Nakryiko btf->hdr->str_off += sz; 23384a3b33f8SAndrii Nakryiko return 0; 23394a3b33f8SAndrii Nakryiko } 23404a3b33f8SAndrii Nakryiko 23414a3b33f8SAndrii Nakryiko /* 23424a3b33f8SAndrii Nakryiko * Append new BTF_KIND_VAR type with: 23434a3b33f8SAndrii Nakryiko * - *name* - non-empty/non-NULL name; 23444a3b33f8SAndrii Nakryiko * - *linkage* - variable linkage, one of BTF_VAR_STATIC, 23454a3b33f8SAndrii Nakryiko * BTF_VAR_GLOBAL_ALLOCATED, or BTF_VAR_GLOBAL_EXTERN; 23464a3b33f8SAndrii Nakryiko * - *type_id* - type ID of the type describing the type of the variable. 23474a3b33f8SAndrii Nakryiko * Returns: 23484a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 23494a3b33f8SAndrii Nakryiko * - <0, on error. 23504a3b33f8SAndrii Nakryiko */ 23514a3b33f8SAndrii Nakryiko int btf__add_var(struct btf *btf, const char *name, int linkage, int type_id) 23524a3b33f8SAndrii Nakryiko { 23534a3b33f8SAndrii Nakryiko struct btf_type *t; 23544a3b33f8SAndrii Nakryiko struct btf_var *v; 2355c81ed6d8SAndrii Nakryiko int sz, name_off; 23564a3b33f8SAndrii Nakryiko 23574a3b33f8SAndrii Nakryiko /* non-empty name */ 23584a3b33f8SAndrii Nakryiko if (!name || !name[0]) 2359e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 23604a3b33f8SAndrii Nakryiko if (linkage != BTF_VAR_STATIC && linkage != BTF_VAR_GLOBAL_ALLOCATED && 23614a3b33f8SAndrii Nakryiko linkage != BTF_VAR_GLOBAL_EXTERN) 2362e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 23634a3b33f8SAndrii Nakryiko if (validate_type_id(type_id)) 2364e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 23654a3b33f8SAndrii Nakryiko 23664a3b33f8SAndrii Nakryiko /* deconstruct BTF, if necessary, and invalidate raw_data */ 23674a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 2368e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 23694a3b33f8SAndrii Nakryiko 23704a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_type) + sizeof(struct btf_var); 23714a3b33f8SAndrii Nakryiko t = btf_add_type_mem(btf, sz); 23724a3b33f8SAndrii Nakryiko if (!t) 2373e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 23744a3b33f8SAndrii Nakryiko 23754a3b33f8SAndrii Nakryiko name_off = btf__add_str(btf, name); 23764a3b33f8SAndrii Nakryiko if (name_off < 0) 23774a3b33f8SAndrii Nakryiko return name_off; 23784a3b33f8SAndrii Nakryiko 23794a3b33f8SAndrii Nakryiko t->name_off = name_off; 23804a3b33f8SAndrii Nakryiko t->info = btf_type_info(BTF_KIND_VAR, 0, 0); 23814a3b33f8SAndrii Nakryiko t->type = type_id; 23824a3b33f8SAndrii Nakryiko 23834a3b33f8SAndrii Nakryiko v = btf_var(t); 23844a3b33f8SAndrii Nakryiko v->linkage = linkage; 23854a3b33f8SAndrii Nakryiko 2386c81ed6d8SAndrii Nakryiko return btf_commit_type(btf, sz); 23874a3b33f8SAndrii Nakryiko } 23884a3b33f8SAndrii Nakryiko 23894a3b33f8SAndrii Nakryiko /* 23904a3b33f8SAndrii Nakryiko * Append new BTF_KIND_DATASEC type with: 23914a3b33f8SAndrii Nakryiko * - *name* - non-empty/non-NULL name; 23924a3b33f8SAndrii Nakryiko * - *byte_sz* - data section size, in bytes. 23934a3b33f8SAndrii Nakryiko * 23944a3b33f8SAndrii Nakryiko * Data section is initially empty. Variables info can be added with 23954a3b33f8SAndrii Nakryiko * btf__add_datasec_var_info() calls, after btf__add_datasec() succeeds. 23964a3b33f8SAndrii Nakryiko * 23974a3b33f8SAndrii Nakryiko * Returns: 23984a3b33f8SAndrii Nakryiko * - >0, type ID of newly added BTF type; 23994a3b33f8SAndrii Nakryiko * - <0, on error. 24004a3b33f8SAndrii Nakryiko */ 24014a3b33f8SAndrii Nakryiko int btf__add_datasec(struct btf *btf, const char *name, __u32 byte_sz) 24024a3b33f8SAndrii Nakryiko { 24034a3b33f8SAndrii Nakryiko struct btf_type *t; 2404c81ed6d8SAndrii Nakryiko int sz, name_off; 24054a3b33f8SAndrii Nakryiko 24064a3b33f8SAndrii Nakryiko /* non-empty name */ 24074a3b33f8SAndrii Nakryiko if (!name || !name[0]) 2408e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 24094a3b33f8SAndrii Nakryiko 24104a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 2411e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 24124a3b33f8SAndrii Nakryiko 24134a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_type); 24144a3b33f8SAndrii Nakryiko t = btf_add_type_mem(btf, sz); 24154a3b33f8SAndrii Nakryiko if (!t) 2416e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 24174a3b33f8SAndrii Nakryiko 24184a3b33f8SAndrii Nakryiko name_off = btf__add_str(btf, name); 24194a3b33f8SAndrii Nakryiko if (name_off < 0) 24204a3b33f8SAndrii Nakryiko return name_off; 24214a3b33f8SAndrii Nakryiko 24224a3b33f8SAndrii Nakryiko /* start with vlen=0, which will be update as var_secinfos are added */ 24234a3b33f8SAndrii Nakryiko t->name_off = name_off; 24244a3b33f8SAndrii Nakryiko t->info = btf_type_info(BTF_KIND_DATASEC, 0, 0); 24254a3b33f8SAndrii Nakryiko t->size = byte_sz; 24264a3b33f8SAndrii Nakryiko 2427c81ed6d8SAndrii Nakryiko return btf_commit_type(btf, sz); 24284a3b33f8SAndrii Nakryiko } 24294a3b33f8SAndrii Nakryiko 24304a3b33f8SAndrii Nakryiko /* 24314a3b33f8SAndrii Nakryiko * Append new data section variable information entry for current DATASEC type: 24324a3b33f8SAndrii Nakryiko * - *var_type_id* - type ID, describing type of the variable; 24334a3b33f8SAndrii Nakryiko * - *offset* - variable offset within data section, in bytes; 24344a3b33f8SAndrii Nakryiko * - *byte_sz* - variable size, in bytes. 24354a3b33f8SAndrii Nakryiko * 24364a3b33f8SAndrii Nakryiko * Returns: 24374a3b33f8SAndrii Nakryiko * - 0, on success; 24384a3b33f8SAndrii Nakryiko * - <0, on error. 24394a3b33f8SAndrii Nakryiko */ 24404a3b33f8SAndrii Nakryiko int btf__add_datasec_var_info(struct btf *btf, int var_type_id, __u32 offset, __u32 byte_sz) 24414a3b33f8SAndrii Nakryiko { 24424a3b33f8SAndrii Nakryiko struct btf_type *t; 24434a3b33f8SAndrii Nakryiko struct btf_var_secinfo *v; 24444a3b33f8SAndrii Nakryiko int sz; 24454a3b33f8SAndrii Nakryiko 24464a3b33f8SAndrii Nakryiko /* last type should be BTF_KIND_DATASEC */ 24474a3b33f8SAndrii Nakryiko if (btf->nr_types == 0) 2448e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 2449c81ed6d8SAndrii Nakryiko t = btf_last_type(btf); 24504a3b33f8SAndrii Nakryiko if (!btf_is_datasec(t)) 2451e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 24524a3b33f8SAndrii Nakryiko 24534a3b33f8SAndrii Nakryiko if (validate_type_id(var_type_id)) 2454e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 24554a3b33f8SAndrii Nakryiko 24564a3b33f8SAndrii Nakryiko /* decompose and invalidate raw data */ 24574a3b33f8SAndrii Nakryiko if (btf_ensure_modifiable(btf)) 2458e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 24594a3b33f8SAndrii Nakryiko 24604a3b33f8SAndrii Nakryiko sz = sizeof(struct btf_var_secinfo); 24614a3b33f8SAndrii Nakryiko v = btf_add_type_mem(btf, sz); 24624a3b33f8SAndrii Nakryiko if (!v) 2463e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 24644a3b33f8SAndrii Nakryiko 24654a3b33f8SAndrii Nakryiko v->type = var_type_id; 24664a3b33f8SAndrii Nakryiko v->offset = offset; 24674a3b33f8SAndrii Nakryiko v->size = byte_sz; 24684a3b33f8SAndrii Nakryiko 24694a3b33f8SAndrii Nakryiko /* update parent type's vlen */ 2470c81ed6d8SAndrii Nakryiko t = btf_last_type(btf); 24714a3b33f8SAndrii Nakryiko btf_type_inc_vlen(t); 24724a3b33f8SAndrii Nakryiko 24734a3b33f8SAndrii Nakryiko btf->hdr->type_len += sz; 24744a3b33f8SAndrii Nakryiko btf->hdr->str_off += sz; 24754a3b33f8SAndrii Nakryiko return 0; 24764a3b33f8SAndrii Nakryiko } 24774a3b33f8SAndrii Nakryiko 24785b84bd10SYonghong Song /* 2479223f903eSYonghong Song * Append new BTF_KIND_DECL_TAG type with: 24805b84bd10SYonghong Song * - *value* - non-empty/non-NULL string; 24815b84bd10SYonghong Song * - *ref_type_id* - referenced type ID, it might not exist yet; 24825b84bd10SYonghong Song * - *component_idx* - -1 for tagging reference type, otherwise struct/union 24835b84bd10SYonghong Song * member or function argument index; 24845b84bd10SYonghong Song * Returns: 24855b84bd10SYonghong Song * - >0, type ID of newly added BTF type; 24865b84bd10SYonghong Song * - <0, on error. 24875b84bd10SYonghong Song */ 2488223f903eSYonghong Song int btf__add_decl_tag(struct btf *btf, const char *value, int ref_type_id, 24895b84bd10SYonghong Song int component_idx) 24905b84bd10SYonghong Song { 24915b84bd10SYonghong Song struct btf_type *t; 24925b84bd10SYonghong Song int sz, value_off; 24935b84bd10SYonghong Song 24945b84bd10SYonghong Song if (!value || !value[0] || component_idx < -1) 24955b84bd10SYonghong Song return libbpf_err(-EINVAL); 24965b84bd10SYonghong Song 24975b84bd10SYonghong Song if (validate_type_id(ref_type_id)) 24985b84bd10SYonghong Song return libbpf_err(-EINVAL); 24995b84bd10SYonghong Song 25005b84bd10SYonghong Song if (btf_ensure_modifiable(btf)) 25015b84bd10SYonghong Song return libbpf_err(-ENOMEM); 25025b84bd10SYonghong Song 2503223f903eSYonghong Song sz = sizeof(struct btf_type) + sizeof(struct btf_decl_tag); 25045b84bd10SYonghong Song t = btf_add_type_mem(btf, sz); 25055b84bd10SYonghong Song if (!t) 25065b84bd10SYonghong Song return libbpf_err(-ENOMEM); 25075b84bd10SYonghong Song 25085b84bd10SYonghong Song value_off = btf__add_str(btf, value); 25095b84bd10SYonghong Song if (value_off < 0) 25105b84bd10SYonghong Song return value_off; 25115b84bd10SYonghong Song 25125b84bd10SYonghong Song t->name_off = value_off; 2513223f903eSYonghong Song t->info = btf_type_info(BTF_KIND_DECL_TAG, 0, false); 25145b84bd10SYonghong Song t->type = ref_type_id; 2515223f903eSYonghong Song btf_decl_tag(t)->component_idx = component_idx; 25165b84bd10SYonghong Song 25175b84bd10SYonghong Song return btf_commit_type(btf, sz); 25185b84bd10SYonghong Song } 25195b84bd10SYonghong Song 2520ae4ab4b4SAndrii Nakryiko struct btf_ext_sec_setup_param { 25213d650141SMartin KaFai Lau __u32 off; 25223d650141SMartin KaFai Lau __u32 len; 25233d650141SMartin KaFai Lau __u32 min_rec_size; 25243d650141SMartin KaFai Lau struct btf_ext_info *ext_info; 25253d650141SMartin KaFai Lau const char *desc; 25263d650141SMartin KaFai Lau }; 25273d650141SMartin KaFai Lau 2528ae4ab4b4SAndrii Nakryiko static int btf_ext_setup_info(struct btf_ext *btf_ext, 2529ae4ab4b4SAndrii Nakryiko struct btf_ext_sec_setup_param *ext_sec) 25302993e051SYonghong Song { 25313d650141SMartin KaFai Lau const struct btf_ext_info_sec *sinfo; 25323d650141SMartin KaFai Lau struct btf_ext_info *ext_info; 2533f0187f0bSMartin KaFai Lau __u32 info_left, record_size; 2534f0187f0bSMartin KaFai Lau /* The start of the info sec (including the __u32 record_size). */ 2535ae4ab4b4SAndrii Nakryiko void *info; 2536f0187f0bSMartin KaFai Lau 25374cedc0daSAndrii Nakryiko if (ext_sec->len == 0) 25384cedc0daSAndrii Nakryiko return 0; 25394cedc0daSAndrii Nakryiko 25403d650141SMartin KaFai Lau if (ext_sec->off & 0x03) { 25418461ef8bSYonghong Song pr_debug(".BTF.ext %s section is not aligned to 4 bytes\n", 25423d650141SMartin KaFai Lau ext_sec->desc); 2543f0187f0bSMartin KaFai Lau return -EINVAL; 2544f0187f0bSMartin KaFai Lau } 2545f0187f0bSMartin KaFai Lau 2546ae4ab4b4SAndrii Nakryiko info = btf_ext->data + btf_ext->hdr->hdr_len + ext_sec->off; 2547ae4ab4b4SAndrii Nakryiko info_left = ext_sec->len; 2548ae4ab4b4SAndrii Nakryiko 2549ae4ab4b4SAndrii Nakryiko if (btf_ext->data + btf_ext->data_size < info + ext_sec->len) { 25508461ef8bSYonghong Song pr_debug("%s section (off:%u len:%u) is beyond the end of the ELF section .BTF.ext\n", 25513d650141SMartin KaFai Lau ext_sec->desc, ext_sec->off, ext_sec->len); 2552f0187f0bSMartin KaFai Lau return -EINVAL; 2553f0187f0bSMartin KaFai Lau } 2554f0187f0bSMartin KaFai Lau 25553d650141SMartin KaFai Lau /* At least a record size */ 2556f0187f0bSMartin KaFai Lau if (info_left < sizeof(__u32)) { 25578461ef8bSYonghong Song pr_debug(".BTF.ext %s record size not found\n", ext_sec->desc); 25582993e051SYonghong Song return -EINVAL; 25592993e051SYonghong Song } 25602993e051SYonghong Song 2561f0187f0bSMartin KaFai Lau /* The record size needs to meet the minimum standard */ 2562f0187f0bSMartin KaFai Lau record_size = *(__u32 *)info; 25633d650141SMartin KaFai Lau if (record_size < ext_sec->min_rec_size || 2564f0187f0bSMartin KaFai Lau record_size & 0x03) { 25658461ef8bSYonghong Song pr_debug("%s section in .BTF.ext has invalid record size %u\n", 25663d650141SMartin KaFai Lau ext_sec->desc, record_size); 25672993e051SYonghong Song return -EINVAL; 25682993e051SYonghong Song } 25692993e051SYonghong Song 2570f0187f0bSMartin KaFai Lau sinfo = info + sizeof(__u32); 2571f0187f0bSMartin KaFai Lau info_left -= sizeof(__u32); 25722993e051SYonghong Song 25733d650141SMartin KaFai Lau /* If no records, return failure now so .BTF.ext won't be used. */ 2574f0187f0bSMartin KaFai Lau if (!info_left) { 25758461ef8bSYonghong Song pr_debug("%s section in .BTF.ext has no records", ext_sec->desc); 25762993e051SYonghong Song return -EINVAL; 25772993e051SYonghong Song } 25782993e051SYonghong Song 2579f0187f0bSMartin KaFai Lau while (info_left) { 25803d650141SMartin KaFai Lau unsigned int sec_hdrlen = sizeof(struct btf_ext_info_sec); 2581f0187f0bSMartin KaFai Lau __u64 total_record_size; 2582f0187f0bSMartin KaFai Lau __u32 num_records; 2583f0187f0bSMartin KaFai Lau 2584f0187f0bSMartin KaFai Lau if (info_left < sec_hdrlen) { 25858461ef8bSYonghong Song pr_debug("%s section header is not found in .BTF.ext\n", 25863d650141SMartin KaFai Lau ext_sec->desc); 25872993e051SYonghong Song return -EINVAL; 25882993e051SYonghong Song } 25892993e051SYonghong Song 25903d650141SMartin KaFai Lau num_records = sinfo->num_info; 25912993e051SYonghong Song if (num_records == 0) { 25928461ef8bSYonghong Song pr_debug("%s section has incorrect num_records in .BTF.ext\n", 25933d650141SMartin KaFai Lau ext_sec->desc); 25942993e051SYonghong Song return -EINVAL; 25952993e051SYonghong Song } 25962993e051SYonghong Song 25972993e051SYonghong Song total_record_size = sec_hdrlen + 25982993e051SYonghong Song (__u64)num_records * record_size; 2599f0187f0bSMartin KaFai Lau if (info_left < total_record_size) { 26008461ef8bSYonghong Song pr_debug("%s section has incorrect num_records in .BTF.ext\n", 26013d650141SMartin KaFai Lau ext_sec->desc); 26022993e051SYonghong Song return -EINVAL; 26032993e051SYonghong Song } 26042993e051SYonghong Song 2605f0187f0bSMartin KaFai Lau info_left -= total_record_size; 26062993e051SYonghong Song sinfo = (void *)sinfo + total_record_size; 26072993e051SYonghong Song } 26082993e051SYonghong Song 26093d650141SMartin KaFai Lau ext_info = ext_sec->ext_info; 26103d650141SMartin KaFai Lau ext_info->len = ext_sec->len - sizeof(__u32); 26113d650141SMartin KaFai Lau ext_info->rec_size = record_size; 2612ae4ab4b4SAndrii Nakryiko ext_info->info = info + sizeof(__u32); 2613f0187f0bSMartin KaFai Lau 26142993e051SYonghong Song return 0; 26152993e051SYonghong Song } 26162993e051SYonghong Song 2617ae4ab4b4SAndrii Nakryiko static int btf_ext_setup_func_info(struct btf_ext *btf_ext) 26183d650141SMartin KaFai Lau { 2619ae4ab4b4SAndrii Nakryiko struct btf_ext_sec_setup_param param = { 2620ae4ab4b4SAndrii Nakryiko .off = btf_ext->hdr->func_info_off, 2621ae4ab4b4SAndrii Nakryiko .len = btf_ext->hdr->func_info_len, 26223d650141SMartin KaFai Lau .min_rec_size = sizeof(struct bpf_func_info_min), 26233d650141SMartin KaFai Lau .ext_info = &btf_ext->func_info, 26243d650141SMartin KaFai Lau .desc = "func_info" 26253d650141SMartin KaFai Lau }; 26263d650141SMartin KaFai Lau 2627ae4ab4b4SAndrii Nakryiko return btf_ext_setup_info(btf_ext, ¶m); 26283d650141SMartin KaFai Lau } 26293d650141SMartin KaFai Lau 2630ae4ab4b4SAndrii Nakryiko static int btf_ext_setup_line_info(struct btf_ext *btf_ext) 26313d650141SMartin KaFai Lau { 2632ae4ab4b4SAndrii Nakryiko struct btf_ext_sec_setup_param param = { 2633ae4ab4b4SAndrii Nakryiko .off = btf_ext->hdr->line_info_off, 2634ae4ab4b4SAndrii Nakryiko .len = btf_ext->hdr->line_info_len, 26353d650141SMartin KaFai Lau .min_rec_size = sizeof(struct bpf_line_info_min), 26363d650141SMartin KaFai Lau .ext_info = &btf_ext->line_info, 26373d650141SMartin KaFai Lau .desc = "line_info", 26383d650141SMartin KaFai Lau }; 26393d650141SMartin KaFai Lau 2640ae4ab4b4SAndrii Nakryiko return btf_ext_setup_info(btf_ext, ¶m); 26413d650141SMartin KaFai Lau } 26423d650141SMartin KaFai Lau 264328b93c64SAndrii Nakryiko static int btf_ext_setup_core_relos(struct btf_ext *btf_ext) 26444cedc0daSAndrii Nakryiko { 26454cedc0daSAndrii Nakryiko struct btf_ext_sec_setup_param param = { 264628b93c64SAndrii Nakryiko .off = btf_ext->hdr->core_relo_off, 264728b93c64SAndrii Nakryiko .len = btf_ext->hdr->core_relo_len, 264828b93c64SAndrii Nakryiko .min_rec_size = sizeof(struct bpf_core_relo), 264928b93c64SAndrii Nakryiko .ext_info = &btf_ext->core_relo_info, 265028b93c64SAndrii Nakryiko .desc = "core_relo", 26514cedc0daSAndrii Nakryiko }; 26524cedc0daSAndrii Nakryiko 26534cedc0daSAndrii Nakryiko return btf_ext_setup_info(btf_ext, ¶m); 26544cedc0daSAndrii Nakryiko } 26554cedc0daSAndrii Nakryiko 26568461ef8bSYonghong Song static int btf_ext_parse_hdr(__u8 *data, __u32 data_size) 26572993e051SYonghong Song { 26582993e051SYonghong Song const struct btf_ext_header *hdr = (struct btf_ext_header *)data; 26592993e051SYonghong Song 26604cedc0daSAndrii Nakryiko if (data_size < offsetofend(struct btf_ext_header, hdr_len) || 26612993e051SYonghong Song data_size < hdr->hdr_len) { 26628461ef8bSYonghong Song pr_debug("BTF.ext header not found"); 26632993e051SYonghong Song return -EINVAL; 26642993e051SYonghong Song } 26652993e051SYonghong Song 26663289959bSAndrii Nakryiko if (hdr->magic == bswap_16(BTF_MAGIC)) { 26673289959bSAndrii Nakryiko pr_warn("BTF.ext in non-native endianness is not supported\n"); 26683289959bSAndrii Nakryiko return -ENOTSUP; 26693289959bSAndrii Nakryiko } else if (hdr->magic != BTF_MAGIC) { 26708461ef8bSYonghong Song pr_debug("Invalid BTF.ext magic:%x\n", hdr->magic); 26712993e051SYonghong Song return -EINVAL; 26722993e051SYonghong Song } 26732993e051SYonghong Song 26742993e051SYonghong Song if (hdr->version != BTF_VERSION) { 26758461ef8bSYonghong Song pr_debug("Unsupported BTF.ext version:%u\n", hdr->version); 26762993e051SYonghong Song return -ENOTSUP; 26772993e051SYonghong Song } 26782993e051SYonghong Song 26792993e051SYonghong Song if (hdr->flags) { 26808461ef8bSYonghong Song pr_debug("Unsupported BTF.ext flags:%x\n", hdr->flags); 26812993e051SYonghong Song return -ENOTSUP; 26822993e051SYonghong Song } 26832993e051SYonghong Song 2684f0187f0bSMartin KaFai Lau if (data_size == hdr->hdr_len) { 26858461ef8bSYonghong Song pr_debug("BTF.ext has no data\n"); 26862993e051SYonghong Song return -EINVAL; 26872993e051SYonghong Song } 26882993e051SYonghong Song 2689f0187f0bSMartin KaFai Lau return 0; 26902993e051SYonghong Song } 26912993e051SYonghong Song 26922993e051SYonghong Song void btf_ext__free(struct btf_ext *btf_ext) 26932993e051SYonghong Song { 269450450fc7SAndrii Nakryiko if (IS_ERR_OR_NULL(btf_ext)) 26952993e051SYonghong Song return; 2696ae4ab4b4SAndrii Nakryiko free(btf_ext->data); 26972993e051SYonghong Song free(btf_ext); 26982993e051SYonghong Song } 26992993e051SYonghong Song 27008461ef8bSYonghong Song struct btf_ext *btf_ext__new(__u8 *data, __u32 size) 27012993e051SYonghong Song { 27022993e051SYonghong Song struct btf_ext *btf_ext; 27032993e051SYonghong Song int err; 27042993e051SYonghong Song 27058461ef8bSYonghong Song err = btf_ext_parse_hdr(data, size); 27062993e051SYonghong Song if (err) 2707e9fc3ce9SAndrii Nakryiko return libbpf_err_ptr(err); 27082993e051SYonghong Song 27092993e051SYonghong Song btf_ext = calloc(1, sizeof(struct btf_ext)); 27102993e051SYonghong Song if (!btf_ext) 2711e9fc3ce9SAndrii Nakryiko return libbpf_err_ptr(-ENOMEM); 27122993e051SYonghong Song 2713ae4ab4b4SAndrii Nakryiko btf_ext->data_size = size; 2714ae4ab4b4SAndrii Nakryiko btf_ext->data = malloc(size); 2715ae4ab4b4SAndrii Nakryiko if (!btf_ext->data) { 2716ae4ab4b4SAndrii Nakryiko err = -ENOMEM; 2717ae4ab4b4SAndrii Nakryiko goto done; 27182993e051SYonghong Song } 2719ae4ab4b4SAndrii Nakryiko memcpy(btf_ext->data, data, size); 27202993e051SYonghong Song 2721e9fc3ce9SAndrii Nakryiko if (btf_ext->hdr->hdr_len < offsetofend(struct btf_ext_header, line_info_len)) { 2722e9fc3ce9SAndrii Nakryiko err = -EINVAL; 27234cedc0daSAndrii Nakryiko goto done; 2724e9fc3ce9SAndrii Nakryiko } 2725e9fc3ce9SAndrii Nakryiko 2726ae4ab4b4SAndrii Nakryiko err = btf_ext_setup_func_info(btf_ext); 2727ae4ab4b4SAndrii Nakryiko if (err) 2728ae4ab4b4SAndrii Nakryiko goto done; 2729ae4ab4b4SAndrii Nakryiko 2730ae4ab4b4SAndrii Nakryiko err = btf_ext_setup_line_info(btf_ext); 2731ae4ab4b4SAndrii Nakryiko if (err) 2732ae4ab4b4SAndrii Nakryiko goto done; 2733ae4ab4b4SAndrii Nakryiko 2734e9fc3ce9SAndrii Nakryiko if (btf_ext->hdr->hdr_len < offsetofend(struct btf_ext_header, core_relo_len)) { 2735e9fc3ce9SAndrii Nakryiko err = -EINVAL; 27364cedc0daSAndrii Nakryiko goto done; 2737e9fc3ce9SAndrii Nakryiko } 2738e9fc3ce9SAndrii Nakryiko 273928b93c64SAndrii Nakryiko err = btf_ext_setup_core_relos(btf_ext); 27404cedc0daSAndrii Nakryiko if (err) 27414cedc0daSAndrii Nakryiko goto done; 27424cedc0daSAndrii Nakryiko 2743ae4ab4b4SAndrii Nakryiko done: 27443d650141SMartin KaFai Lau if (err) { 27453d650141SMartin KaFai Lau btf_ext__free(btf_ext); 2746e9fc3ce9SAndrii Nakryiko return libbpf_err_ptr(err); 27473d650141SMartin KaFai Lau } 27483d650141SMartin KaFai Lau 27492993e051SYonghong Song return btf_ext; 27502993e051SYonghong Song } 27512993e051SYonghong Song 2752ae4ab4b4SAndrii Nakryiko const void *btf_ext__get_raw_data(const struct btf_ext *btf_ext, __u32 *size) 2753ae4ab4b4SAndrii Nakryiko { 2754ae4ab4b4SAndrii Nakryiko *size = btf_ext->data_size; 2755ae4ab4b4SAndrii Nakryiko return btf_ext->data; 2756ae4ab4b4SAndrii Nakryiko } 2757ae4ab4b4SAndrii Nakryiko 27583d650141SMartin KaFai Lau static int btf_ext_reloc_info(const struct btf *btf, 27593d650141SMartin KaFai Lau const struct btf_ext_info *ext_info, 27602993e051SYonghong Song const char *sec_name, __u32 insns_cnt, 27613d650141SMartin KaFai Lau void **info, __u32 *cnt) 27622993e051SYonghong Song { 27633d650141SMartin KaFai Lau __u32 sec_hdrlen = sizeof(struct btf_ext_info_sec); 27643d650141SMartin KaFai Lau __u32 i, record_size, existing_len, records_len; 27653d650141SMartin KaFai Lau struct btf_ext_info_sec *sinfo; 27662993e051SYonghong Song const char *info_sec_name; 27672993e051SYonghong Song __u64 remain_len; 27682993e051SYonghong Song void *data; 27692993e051SYonghong Song 27703d650141SMartin KaFai Lau record_size = ext_info->rec_size; 27713d650141SMartin KaFai Lau sinfo = ext_info->info; 27723d650141SMartin KaFai Lau remain_len = ext_info->len; 27732993e051SYonghong Song while (remain_len > 0) { 27743d650141SMartin KaFai Lau records_len = sinfo->num_info * record_size; 27752993e051SYonghong Song info_sec_name = btf__name_by_offset(btf, sinfo->sec_name_off); 27762993e051SYonghong Song if (strcmp(info_sec_name, sec_name)) { 27772993e051SYonghong Song remain_len -= sec_hdrlen + records_len; 27782993e051SYonghong Song sinfo = (void *)sinfo + sec_hdrlen + records_len; 27792993e051SYonghong Song continue; 27802993e051SYonghong Song } 27812993e051SYonghong Song 27823d650141SMartin KaFai Lau existing_len = (*cnt) * record_size; 27833d650141SMartin KaFai Lau data = realloc(*info, existing_len + records_len); 27842993e051SYonghong Song if (!data) 2785e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOMEM); 27862993e051SYonghong Song 27873d650141SMartin KaFai Lau memcpy(data + existing_len, sinfo->data, records_len); 278884ecc1f9SMartin KaFai Lau /* adjust insn_off only, the rest data will be passed 27892993e051SYonghong Song * to the kernel. 27902993e051SYonghong Song */ 27913d650141SMartin KaFai Lau for (i = 0; i < sinfo->num_info; i++) { 27923d650141SMartin KaFai Lau __u32 *insn_off; 27932993e051SYonghong Song 27943d650141SMartin KaFai Lau insn_off = data + existing_len + (i * record_size); 2795e9fc3ce9SAndrii Nakryiko *insn_off = *insn_off / sizeof(struct bpf_insn) + insns_cnt; 27962993e051SYonghong Song } 27973d650141SMartin KaFai Lau *info = data; 27983d650141SMartin KaFai Lau *cnt += sinfo->num_info; 27992993e051SYonghong Song return 0; 28002993e051SYonghong Song } 28012993e051SYonghong Song 2802e9fc3ce9SAndrii Nakryiko return libbpf_err(-ENOENT); 2803f0187f0bSMartin KaFai Lau } 2804f0187f0bSMartin KaFai Lau 2805ae4ab4b4SAndrii Nakryiko int btf_ext__reloc_func_info(const struct btf *btf, 2806ae4ab4b4SAndrii Nakryiko const struct btf_ext *btf_ext, 28073d650141SMartin KaFai Lau const char *sec_name, __u32 insns_cnt, 28083d650141SMartin KaFai Lau void **func_info, __u32 *cnt) 28093d650141SMartin KaFai Lau { 28103d650141SMartin KaFai Lau return btf_ext_reloc_info(btf, &btf_ext->func_info, sec_name, 28113d650141SMartin KaFai Lau insns_cnt, func_info, cnt); 28123d650141SMartin KaFai Lau } 28133d650141SMartin KaFai Lau 2814ae4ab4b4SAndrii Nakryiko int btf_ext__reloc_line_info(const struct btf *btf, 2815ae4ab4b4SAndrii Nakryiko const struct btf_ext *btf_ext, 28163d650141SMartin KaFai Lau const char *sec_name, __u32 insns_cnt, 28173d650141SMartin KaFai Lau void **line_info, __u32 *cnt) 28183d650141SMartin KaFai Lau { 28193d650141SMartin KaFai Lau return btf_ext_reloc_info(btf, &btf_ext->line_info, sec_name, 28203d650141SMartin KaFai Lau insns_cnt, line_info, cnt); 28213d650141SMartin KaFai Lau } 28223d650141SMartin KaFai Lau 2823f0187f0bSMartin KaFai Lau __u32 btf_ext__func_info_rec_size(const struct btf_ext *btf_ext) 2824f0187f0bSMartin KaFai Lau { 28253d650141SMartin KaFai Lau return btf_ext->func_info.rec_size; 28263d650141SMartin KaFai Lau } 28273d650141SMartin KaFai Lau 28283d650141SMartin KaFai Lau __u32 btf_ext__line_info_rec_size(const struct btf_ext *btf_ext) 28293d650141SMartin KaFai Lau { 28303d650141SMartin KaFai Lau return btf_ext->line_info.rec_size; 28312993e051SYonghong Song } 2832d5caef5bSAndrii Nakryiko 2833d5caef5bSAndrii Nakryiko struct btf_dedup; 2834d5caef5bSAndrii Nakryiko 2835d5caef5bSAndrii Nakryiko static struct btf_dedup *btf_dedup_new(struct btf *btf, struct btf_ext *btf_ext, 2836d5caef5bSAndrii Nakryiko const struct btf_dedup_opts *opts); 2837d5caef5bSAndrii Nakryiko static void btf_dedup_free(struct btf_dedup *d); 2838f86524efSAndrii Nakryiko static int btf_dedup_prep(struct btf_dedup *d); 2839d5caef5bSAndrii Nakryiko static int btf_dedup_strings(struct btf_dedup *d); 2840d5caef5bSAndrii Nakryiko static int btf_dedup_prim_types(struct btf_dedup *d); 2841d5caef5bSAndrii Nakryiko static int btf_dedup_struct_types(struct btf_dedup *d); 2842d5caef5bSAndrii Nakryiko static int btf_dedup_ref_types(struct btf_dedup *d); 2843d5caef5bSAndrii Nakryiko static int btf_dedup_compact_types(struct btf_dedup *d); 2844d5caef5bSAndrii Nakryiko static int btf_dedup_remap_types(struct btf_dedup *d); 2845d5caef5bSAndrii Nakryiko 2846d5caef5bSAndrii Nakryiko /* 2847d5caef5bSAndrii Nakryiko * Deduplicate BTF types and strings. 2848d5caef5bSAndrii Nakryiko * 2849d5caef5bSAndrii Nakryiko * BTF dedup algorithm takes as an input `struct btf` representing `.BTF` ELF 2850d5caef5bSAndrii Nakryiko * section with all BTF type descriptors and string data. It overwrites that 2851d5caef5bSAndrii Nakryiko * memory in-place with deduplicated types and strings without any loss of 2852d5caef5bSAndrii Nakryiko * information. If optional `struct btf_ext` representing '.BTF.ext' ELF section 2853d5caef5bSAndrii Nakryiko * is provided, all the strings referenced from .BTF.ext section are honored 2854d5caef5bSAndrii Nakryiko * and updated to point to the right offsets after deduplication. 2855d5caef5bSAndrii Nakryiko * 2856d5caef5bSAndrii Nakryiko * If function returns with error, type/string data might be garbled and should 2857d5caef5bSAndrii Nakryiko * be discarded. 2858d5caef5bSAndrii Nakryiko * 2859d5caef5bSAndrii Nakryiko * More verbose and detailed description of both problem btf_dedup is solving, 2860d5caef5bSAndrii Nakryiko * as well as solution could be found at: 2861d5caef5bSAndrii Nakryiko * https://facebookmicrosites.github.io/bpf/blog/2018/11/14/btf-enhancement.html 2862d5caef5bSAndrii Nakryiko * 2863d5caef5bSAndrii Nakryiko * Problem description and justification 2864d5caef5bSAndrii Nakryiko * ===================================== 2865d5caef5bSAndrii Nakryiko * 2866d5caef5bSAndrii Nakryiko * BTF type information is typically emitted either as a result of conversion 2867d5caef5bSAndrii Nakryiko * from DWARF to BTF or directly by compiler. In both cases, each compilation 2868d5caef5bSAndrii Nakryiko * unit contains information about a subset of all the types that are used 2869d5caef5bSAndrii Nakryiko * in an application. These subsets are frequently overlapping and contain a lot 2870d5caef5bSAndrii Nakryiko * of duplicated information when later concatenated together into a single 2871d5caef5bSAndrii Nakryiko * binary. This algorithm ensures that each unique type is represented by single 2872d5caef5bSAndrii Nakryiko * BTF type descriptor, greatly reducing resulting size of BTF data. 2873d5caef5bSAndrii Nakryiko * 2874d5caef5bSAndrii Nakryiko * Compilation unit isolation and subsequent duplication of data is not the only 2875d5caef5bSAndrii Nakryiko * problem. The same type hierarchy (e.g., struct and all the type that struct 2876d5caef5bSAndrii Nakryiko * references) in different compilation units can be represented in BTF to 2877d5caef5bSAndrii Nakryiko * various degrees of completeness (or, rather, incompleteness) due to 2878d5caef5bSAndrii Nakryiko * struct/union forward declarations. 2879d5caef5bSAndrii Nakryiko * 2880d5caef5bSAndrii Nakryiko * Let's take a look at an example, that we'll use to better understand the 2881d5caef5bSAndrii Nakryiko * problem (and solution). Suppose we have two compilation units, each using 2882d5caef5bSAndrii Nakryiko * same `struct S`, but each of them having incomplete type information about 2883d5caef5bSAndrii Nakryiko * struct's fields: 2884d5caef5bSAndrii Nakryiko * 2885d5caef5bSAndrii Nakryiko * // CU #1: 2886d5caef5bSAndrii Nakryiko * struct S; 2887d5caef5bSAndrii Nakryiko * struct A { 2888d5caef5bSAndrii Nakryiko * int a; 2889d5caef5bSAndrii Nakryiko * struct A* self; 2890d5caef5bSAndrii Nakryiko * struct S* parent; 2891d5caef5bSAndrii Nakryiko * }; 2892d5caef5bSAndrii Nakryiko * struct B; 2893d5caef5bSAndrii Nakryiko * struct S { 2894d5caef5bSAndrii Nakryiko * struct A* a_ptr; 2895d5caef5bSAndrii Nakryiko * struct B* b_ptr; 2896d5caef5bSAndrii Nakryiko * }; 2897d5caef5bSAndrii Nakryiko * 2898d5caef5bSAndrii Nakryiko * // CU #2: 2899d5caef5bSAndrii Nakryiko * struct S; 2900d5caef5bSAndrii Nakryiko * struct A; 2901d5caef5bSAndrii Nakryiko * struct B { 2902d5caef5bSAndrii Nakryiko * int b; 2903d5caef5bSAndrii Nakryiko * struct B* self; 2904d5caef5bSAndrii Nakryiko * struct S* parent; 2905d5caef5bSAndrii Nakryiko * }; 2906d5caef5bSAndrii Nakryiko * struct S { 2907d5caef5bSAndrii Nakryiko * struct A* a_ptr; 2908d5caef5bSAndrii Nakryiko * struct B* b_ptr; 2909d5caef5bSAndrii Nakryiko * }; 2910d5caef5bSAndrii Nakryiko * 2911d5caef5bSAndrii Nakryiko * In case of CU #1, BTF data will know only that `struct B` exist (but no 2912d5caef5bSAndrii Nakryiko * more), but will know the complete type information about `struct A`. While 2913d5caef5bSAndrii Nakryiko * for CU #2, it will know full type information about `struct B`, but will 2914d5caef5bSAndrii Nakryiko * only know about forward declaration of `struct A` (in BTF terms, it will 2915d5caef5bSAndrii Nakryiko * have `BTF_KIND_FWD` type descriptor with name `B`). 2916d5caef5bSAndrii Nakryiko * 2917d5caef5bSAndrii Nakryiko * This compilation unit isolation means that it's possible that there is no 2918d5caef5bSAndrii Nakryiko * single CU with complete type information describing structs `S`, `A`, and 2919d5caef5bSAndrii Nakryiko * `B`. Also, we might get tons of duplicated and redundant type information. 2920d5caef5bSAndrii Nakryiko * 2921d5caef5bSAndrii Nakryiko * Additional complication we need to keep in mind comes from the fact that 2922d5caef5bSAndrii Nakryiko * types, in general, can form graphs containing cycles, not just DAGs. 2923d5caef5bSAndrii Nakryiko * 2924d5caef5bSAndrii Nakryiko * While algorithm does deduplication, it also merges and resolves type 2925d5caef5bSAndrii Nakryiko * information (unless disabled throught `struct btf_opts`), whenever possible. 2926d5caef5bSAndrii Nakryiko * E.g., in the example above with two compilation units having partial type 2927d5caef5bSAndrii Nakryiko * information for structs `A` and `B`, the output of algorithm will emit 2928d5caef5bSAndrii Nakryiko * a single copy of each BTF type that describes structs `A`, `B`, and `S` 2929d5caef5bSAndrii Nakryiko * (as well as type information for `int` and pointers), as if they were defined 2930d5caef5bSAndrii Nakryiko * in a single compilation unit as: 2931d5caef5bSAndrii Nakryiko * 2932d5caef5bSAndrii Nakryiko * struct A { 2933d5caef5bSAndrii Nakryiko * int a; 2934d5caef5bSAndrii Nakryiko * struct A* self; 2935d5caef5bSAndrii Nakryiko * struct S* parent; 2936d5caef5bSAndrii Nakryiko * }; 2937d5caef5bSAndrii Nakryiko * struct B { 2938d5caef5bSAndrii Nakryiko * int b; 2939d5caef5bSAndrii Nakryiko * struct B* self; 2940d5caef5bSAndrii Nakryiko * struct S* parent; 2941d5caef5bSAndrii Nakryiko * }; 2942d5caef5bSAndrii Nakryiko * struct S { 2943d5caef5bSAndrii Nakryiko * struct A* a_ptr; 2944d5caef5bSAndrii Nakryiko * struct B* b_ptr; 2945d5caef5bSAndrii Nakryiko * }; 2946d5caef5bSAndrii Nakryiko * 2947d5caef5bSAndrii Nakryiko * Algorithm summary 2948d5caef5bSAndrii Nakryiko * ================= 2949d5caef5bSAndrii Nakryiko * 2950d5caef5bSAndrii Nakryiko * Algorithm completes its work in 6 separate passes: 2951d5caef5bSAndrii Nakryiko * 2952d5caef5bSAndrii Nakryiko * 1. Strings deduplication. 2953d5caef5bSAndrii Nakryiko * 2. Primitive types deduplication (int, enum, fwd). 2954d5caef5bSAndrii Nakryiko * 3. Struct/union types deduplication. 2955d5caef5bSAndrii Nakryiko * 4. Reference types deduplication (pointers, typedefs, arrays, funcs, func 2956d5caef5bSAndrii Nakryiko * protos, and const/volatile/restrict modifiers). 2957d5caef5bSAndrii Nakryiko * 5. Types compaction. 2958d5caef5bSAndrii Nakryiko * 6. Types remapping. 2959d5caef5bSAndrii Nakryiko * 2960d5caef5bSAndrii Nakryiko * Algorithm determines canonical type descriptor, which is a single 2961d5caef5bSAndrii Nakryiko * representative type for each truly unique type. This canonical type is the 2962d5caef5bSAndrii Nakryiko * one that will go into final deduplicated BTF type information. For 2963d5caef5bSAndrii Nakryiko * struct/unions, it is also the type that algorithm will merge additional type 2964d5caef5bSAndrii Nakryiko * information into (while resolving FWDs), as it discovers it from data in 2965d5caef5bSAndrii Nakryiko * other CUs. Each input BTF type eventually gets either mapped to itself, if 2966d5caef5bSAndrii Nakryiko * that type is canonical, or to some other type, if that type is equivalent 2967d5caef5bSAndrii Nakryiko * and was chosen as canonical representative. This mapping is stored in 2968d5caef5bSAndrii Nakryiko * `btf_dedup->map` array. This map is also used to record STRUCT/UNION that 2969d5caef5bSAndrii Nakryiko * FWD type got resolved to. 2970d5caef5bSAndrii Nakryiko * 2971d5caef5bSAndrii Nakryiko * To facilitate fast discovery of canonical types, we also maintain canonical 2972d5caef5bSAndrii Nakryiko * index (`btf_dedup->dedup_table`), which maps type descriptor's signature hash 2973d5caef5bSAndrii Nakryiko * (i.e., hashed kind, name, size, fields, etc) into a list of canonical types 2974d5caef5bSAndrii Nakryiko * that match that signature. With sufficiently good choice of type signature 2975d5caef5bSAndrii Nakryiko * hashing function, we can limit number of canonical types for each unique type 2976d5caef5bSAndrii Nakryiko * signature to a very small number, allowing to find canonical type for any 2977d5caef5bSAndrii Nakryiko * duplicated type very quickly. 2978d5caef5bSAndrii Nakryiko * 2979d5caef5bSAndrii Nakryiko * Struct/union deduplication is the most critical part and algorithm for 2980d5caef5bSAndrii Nakryiko * deduplicating structs/unions is described in greater details in comments for 2981d5caef5bSAndrii Nakryiko * `btf_dedup_is_equiv` function. 2982d5caef5bSAndrii Nakryiko */ 2983d5caef5bSAndrii Nakryiko int btf__dedup(struct btf *btf, struct btf_ext *btf_ext, 2984d5caef5bSAndrii Nakryiko const struct btf_dedup_opts *opts) 2985d5caef5bSAndrii Nakryiko { 2986d5caef5bSAndrii Nakryiko struct btf_dedup *d = btf_dedup_new(btf, btf_ext, opts); 2987d5caef5bSAndrii Nakryiko int err; 2988d5caef5bSAndrii Nakryiko 2989d5caef5bSAndrii Nakryiko if (IS_ERR(d)) { 2990d5caef5bSAndrii Nakryiko pr_debug("btf_dedup_new failed: %ld", PTR_ERR(d)); 2991e9fc3ce9SAndrii Nakryiko return libbpf_err(-EINVAL); 2992d5caef5bSAndrii Nakryiko } 2993d5caef5bSAndrii Nakryiko 2994*1000298cSMauricio Vásquez if (btf_ensure_modifiable(btf)) { 2995*1000298cSMauricio Vásquez err = -ENOMEM; 2996*1000298cSMauricio Vásquez goto done; 2997*1000298cSMauricio Vásquez } 2998919d2b1dSAndrii Nakryiko 2999f86524efSAndrii Nakryiko err = btf_dedup_prep(d); 3000f86524efSAndrii Nakryiko if (err) { 3001f86524efSAndrii Nakryiko pr_debug("btf_dedup_prep failed:%d\n", err); 3002f86524efSAndrii Nakryiko goto done; 3003f86524efSAndrii Nakryiko } 3004d5caef5bSAndrii Nakryiko err = btf_dedup_strings(d); 3005d5caef5bSAndrii Nakryiko if (err < 0) { 3006d5caef5bSAndrii Nakryiko pr_debug("btf_dedup_strings failed:%d\n", err); 3007d5caef5bSAndrii Nakryiko goto done; 3008d5caef5bSAndrii Nakryiko } 3009d5caef5bSAndrii Nakryiko err = btf_dedup_prim_types(d); 3010d5caef5bSAndrii Nakryiko if (err < 0) { 3011d5caef5bSAndrii Nakryiko pr_debug("btf_dedup_prim_types failed:%d\n", err); 3012d5caef5bSAndrii Nakryiko goto done; 3013d5caef5bSAndrii Nakryiko } 3014d5caef5bSAndrii Nakryiko err = btf_dedup_struct_types(d); 3015d5caef5bSAndrii Nakryiko if (err < 0) { 3016d5caef5bSAndrii Nakryiko pr_debug("btf_dedup_struct_types failed:%d\n", err); 3017d5caef5bSAndrii Nakryiko goto done; 3018d5caef5bSAndrii Nakryiko } 3019d5caef5bSAndrii Nakryiko err = btf_dedup_ref_types(d); 3020d5caef5bSAndrii Nakryiko if (err < 0) { 3021d5caef5bSAndrii Nakryiko pr_debug("btf_dedup_ref_types failed:%d\n", err); 3022d5caef5bSAndrii Nakryiko goto done; 3023d5caef5bSAndrii Nakryiko } 3024d5caef5bSAndrii Nakryiko err = btf_dedup_compact_types(d); 3025d5caef5bSAndrii Nakryiko if (err < 0) { 3026d5caef5bSAndrii Nakryiko pr_debug("btf_dedup_compact_types failed:%d\n", err); 3027d5caef5bSAndrii Nakryiko goto done; 3028d5caef5bSAndrii Nakryiko } 3029d5caef5bSAndrii Nakryiko err = btf_dedup_remap_types(d); 3030d5caef5bSAndrii Nakryiko if (err < 0) { 3031d5caef5bSAndrii Nakryiko pr_debug("btf_dedup_remap_types failed:%d\n", err); 3032d5caef5bSAndrii Nakryiko goto done; 3033d5caef5bSAndrii Nakryiko } 3034d5caef5bSAndrii Nakryiko 3035d5caef5bSAndrii Nakryiko done: 3036d5caef5bSAndrii Nakryiko btf_dedup_free(d); 3037e9fc3ce9SAndrii Nakryiko return libbpf_err(err); 3038d5caef5bSAndrii Nakryiko } 3039d5caef5bSAndrii Nakryiko 3040d5caef5bSAndrii Nakryiko #define BTF_UNPROCESSED_ID ((__u32)-1) 3041d5caef5bSAndrii Nakryiko #define BTF_IN_PROGRESS_ID ((__u32)-2) 3042d5caef5bSAndrii Nakryiko 3043d5caef5bSAndrii Nakryiko struct btf_dedup { 3044d5caef5bSAndrii Nakryiko /* .BTF section to be deduped in-place */ 3045d5caef5bSAndrii Nakryiko struct btf *btf; 3046d5caef5bSAndrii Nakryiko /* 3047d5caef5bSAndrii Nakryiko * Optional .BTF.ext section. When provided, any strings referenced 3048d5caef5bSAndrii Nakryiko * from it will be taken into account when deduping strings 3049d5caef5bSAndrii Nakryiko */ 3050d5caef5bSAndrii Nakryiko struct btf_ext *btf_ext; 3051d5caef5bSAndrii Nakryiko /* 3052d5caef5bSAndrii Nakryiko * This is a map from any type's signature hash to a list of possible 3053d5caef5bSAndrii Nakryiko * canonical representative type candidates. Hash collisions are 3054d5caef5bSAndrii Nakryiko * ignored, so even types of various kinds can share same list of 3055d5caef5bSAndrii Nakryiko * candidates, which is fine because we rely on subsequent 3056d5caef5bSAndrii Nakryiko * btf_xxx_equal() checks to authoritatively verify type equality. 3057d5caef5bSAndrii Nakryiko */ 30582fc3fc0bSAndrii Nakryiko struct hashmap *dedup_table; 3059d5caef5bSAndrii Nakryiko /* Canonical types map */ 3060d5caef5bSAndrii Nakryiko __u32 *map; 3061d5caef5bSAndrii Nakryiko /* Hypothetical mapping, used during type graph equivalence checks */ 3062d5caef5bSAndrii Nakryiko __u32 *hypot_map; 3063d5caef5bSAndrii Nakryiko __u32 *hypot_list; 3064d5caef5bSAndrii Nakryiko size_t hypot_cnt; 3065d5caef5bSAndrii Nakryiko size_t hypot_cap; 3066f86524efSAndrii Nakryiko /* Whether hypothetical mapping, if successful, would need to adjust 3067f86524efSAndrii Nakryiko * already canonicalized types (due to a new forward declaration to 3068f86524efSAndrii Nakryiko * concrete type resolution). In such case, during split BTF dedup 3069f86524efSAndrii Nakryiko * candidate type would still be considered as different, because base 3070f86524efSAndrii Nakryiko * BTF is considered to be immutable. 3071f86524efSAndrii Nakryiko */ 3072f86524efSAndrii Nakryiko bool hypot_adjust_canon; 3073d5caef5bSAndrii Nakryiko /* Various option modifying behavior of algorithm */ 3074d5caef5bSAndrii Nakryiko struct btf_dedup_opts opts; 307588a82c2aSAndrii Nakryiko /* temporary strings deduplication state */ 307690d76d3eSAndrii Nakryiko struct strset *strs_set; 3077d5caef5bSAndrii Nakryiko }; 3078d5caef5bSAndrii Nakryiko 30792fc3fc0bSAndrii Nakryiko static long hash_combine(long h, long value) 3080d5caef5bSAndrii Nakryiko { 30812fc3fc0bSAndrii Nakryiko return h * 31 + value; 3082d5caef5bSAndrii Nakryiko } 3083d5caef5bSAndrii Nakryiko 30842fc3fc0bSAndrii Nakryiko #define for_each_dedup_cand(d, node, hash) \ 30852fc3fc0bSAndrii Nakryiko hashmap__for_each_key_entry(d->dedup_table, node, (void *)hash) 3086d5caef5bSAndrii Nakryiko 30872fc3fc0bSAndrii Nakryiko static int btf_dedup_table_add(struct btf_dedup *d, long hash, __u32 type_id) 3088d5caef5bSAndrii Nakryiko { 30892fc3fc0bSAndrii Nakryiko return hashmap__append(d->dedup_table, 30902fc3fc0bSAndrii Nakryiko (void *)hash, (void *)(long)type_id); 3091d5caef5bSAndrii Nakryiko } 3092d5caef5bSAndrii Nakryiko 3093d5caef5bSAndrii Nakryiko static int btf_dedup_hypot_map_add(struct btf_dedup *d, 3094d5caef5bSAndrii Nakryiko __u32 from_id, __u32 to_id) 3095d5caef5bSAndrii Nakryiko { 3096d5caef5bSAndrii Nakryiko if (d->hypot_cnt == d->hypot_cap) { 3097d5caef5bSAndrii Nakryiko __u32 *new_list; 3098d5caef5bSAndrii Nakryiko 3099fb2426adSMartin KaFai Lau d->hypot_cap += max((size_t)16, d->hypot_cap / 2); 3100029258d7SAndrii Nakryiko new_list = libbpf_reallocarray(d->hypot_list, d->hypot_cap, sizeof(__u32)); 3101d5caef5bSAndrii Nakryiko if (!new_list) 3102d5caef5bSAndrii Nakryiko return -ENOMEM; 3103d5caef5bSAndrii Nakryiko d->hypot_list = new_list; 3104d5caef5bSAndrii Nakryiko } 3105d5caef5bSAndrii Nakryiko d->hypot_list[d->hypot_cnt++] = from_id; 3106d5caef5bSAndrii Nakryiko d->hypot_map[from_id] = to_id; 3107d5caef5bSAndrii Nakryiko return 0; 3108d5caef5bSAndrii Nakryiko } 3109d5caef5bSAndrii Nakryiko 3110d5caef5bSAndrii Nakryiko static void btf_dedup_clear_hypot_map(struct btf_dedup *d) 3111d5caef5bSAndrii Nakryiko { 3112d5caef5bSAndrii Nakryiko int i; 3113d5caef5bSAndrii Nakryiko 3114d5caef5bSAndrii Nakryiko for (i = 0; i < d->hypot_cnt; i++) 3115d5caef5bSAndrii Nakryiko d->hypot_map[d->hypot_list[i]] = BTF_UNPROCESSED_ID; 3116d5caef5bSAndrii Nakryiko d->hypot_cnt = 0; 3117f86524efSAndrii Nakryiko d->hypot_adjust_canon = false; 3118d5caef5bSAndrii Nakryiko } 3119d5caef5bSAndrii Nakryiko 3120d5caef5bSAndrii Nakryiko static void btf_dedup_free(struct btf_dedup *d) 3121d5caef5bSAndrii Nakryiko { 31222fc3fc0bSAndrii Nakryiko hashmap__free(d->dedup_table); 31232fc3fc0bSAndrii Nakryiko d->dedup_table = NULL; 3124d5caef5bSAndrii Nakryiko 3125d5caef5bSAndrii Nakryiko free(d->map); 3126d5caef5bSAndrii Nakryiko d->map = NULL; 3127d5caef5bSAndrii Nakryiko 3128d5caef5bSAndrii Nakryiko free(d->hypot_map); 3129d5caef5bSAndrii Nakryiko d->hypot_map = NULL; 3130d5caef5bSAndrii Nakryiko 3131d5caef5bSAndrii Nakryiko free(d->hypot_list); 3132d5caef5bSAndrii Nakryiko d->hypot_list = NULL; 3133d5caef5bSAndrii Nakryiko 3134d5caef5bSAndrii Nakryiko free(d); 3135d5caef5bSAndrii Nakryiko } 3136d5caef5bSAndrii Nakryiko 31372fc3fc0bSAndrii Nakryiko static size_t btf_dedup_identity_hash_fn(const void *key, void *ctx) 313851edf5f6SAndrii Nakryiko { 31392fc3fc0bSAndrii Nakryiko return (size_t)key; 314051edf5f6SAndrii Nakryiko } 314151edf5f6SAndrii Nakryiko 31422fc3fc0bSAndrii Nakryiko static size_t btf_dedup_collision_hash_fn(const void *key, void *ctx) 31432fc3fc0bSAndrii Nakryiko { 31442fc3fc0bSAndrii Nakryiko return 0; 31452fc3fc0bSAndrii Nakryiko } 31462fc3fc0bSAndrii Nakryiko 31472fc3fc0bSAndrii Nakryiko static bool btf_dedup_equal_fn(const void *k1, const void *k2, void *ctx) 31482fc3fc0bSAndrii Nakryiko { 31492fc3fc0bSAndrii Nakryiko return k1 == k2; 31502fc3fc0bSAndrii Nakryiko } 315151edf5f6SAndrii Nakryiko 3152d5caef5bSAndrii Nakryiko static struct btf_dedup *btf_dedup_new(struct btf *btf, struct btf_ext *btf_ext, 3153d5caef5bSAndrii Nakryiko const struct btf_dedup_opts *opts) 3154d5caef5bSAndrii Nakryiko { 3155d5caef5bSAndrii Nakryiko struct btf_dedup *d = calloc(1, sizeof(struct btf_dedup)); 31562fc3fc0bSAndrii Nakryiko hashmap_hash_fn hash_fn = btf_dedup_identity_hash_fn; 3157f86524efSAndrii Nakryiko int i, err = 0, type_cnt; 3158d5caef5bSAndrii Nakryiko 3159d5caef5bSAndrii Nakryiko if (!d) 3160d5caef5bSAndrii Nakryiko return ERR_PTR(-ENOMEM); 3161d5caef5bSAndrii Nakryiko 316251edf5f6SAndrii Nakryiko d->opts.dont_resolve_fwds = opts && opts->dont_resolve_fwds; 31632fc3fc0bSAndrii Nakryiko /* dedup_table_size is now used only to force collisions in tests */ 31642fc3fc0bSAndrii Nakryiko if (opts && opts->dedup_table_size == 1) 31652fc3fc0bSAndrii Nakryiko hash_fn = btf_dedup_collision_hash_fn; 316651edf5f6SAndrii Nakryiko 3167d5caef5bSAndrii Nakryiko d->btf = btf; 3168d5caef5bSAndrii Nakryiko d->btf_ext = btf_ext; 3169d5caef5bSAndrii Nakryiko 31702fc3fc0bSAndrii Nakryiko d->dedup_table = hashmap__new(hash_fn, btf_dedup_equal_fn, NULL); 31712fc3fc0bSAndrii Nakryiko if (IS_ERR(d->dedup_table)) { 31722fc3fc0bSAndrii Nakryiko err = PTR_ERR(d->dedup_table); 31732fc3fc0bSAndrii Nakryiko d->dedup_table = NULL; 3174d5caef5bSAndrii Nakryiko goto done; 3175d5caef5bSAndrii Nakryiko } 3176d5caef5bSAndrii Nakryiko 3177f86524efSAndrii Nakryiko type_cnt = btf__get_nr_types(btf) + 1; 3178f86524efSAndrii Nakryiko d->map = malloc(sizeof(__u32) * type_cnt); 3179d5caef5bSAndrii Nakryiko if (!d->map) { 3180d5caef5bSAndrii Nakryiko err = -ENOMEM; 3181d5caef5bSAndrii Nakryiko goto done; 3182d5caef5bSAndrii Nakryiko } 3183d5caef5bSAndrii Nakryiko /* special BTF "void" type is made canonical immediately */ 3184d5caef5bSAndrii Nakryiko d->map[0] = 0; 3185f86524efSAndrii Nakryiko for (i = 1; i < type_cnt; i++) { 3186740e69c3SAndrii Nakryiko struct btf_type *t = btf_type_by_id(d->btf, i); 3187189cf5a4SAndrii Nakryiko 3188189cf5a4SAndrii Nakryiko /* VAR and DATASEC are never deduped and are self-canonical */ 3189b03bc685SAndrii Nakryiko if (btf_is_var(t) || btf_is_datasec(t)) 3190189cf5a4SAndrii Nakryiko d->map[i] = i; 3191189cf5a4SAndrii Nakryiko else 3192d5caef5bSAndrii Nakryiko d->map[i] = BTF_UNPROCESSED_ID; 3193189cf5a4SAndrii Nakryiko } 3194d5caef5bSAndrii Nakryiko 3195f86524efSAndrii Nakryiko d->hypot_map = malloc(sizeof(__u32) * type_cnt); 3196d5caef5bSAndrii Nakryiko if (!d->hypot_map) { 3197d5caef5bSAndrii Nakryiko err = -ENOMEM; 3198d5caef5bSAndrii Nakryiko goto done; 3199d5caef5bSAndrii Nakryiko } 3200f86524efSAndrii Nakryiko for (i = 0; i < type_cnt; i++) 3201d5caef5bSAndrii Nakryiko d->hypot_map[i] = BTF_UNPROCESSED_ID; 3202d5caef5bSAndrii Nakryiko 3203d5caef5bSAndrii Nakryiko done: 3204d5caef5bSAndrii Nakryiko if (err) { 3205d5caef5bSAndrii Nakryiko btf_dedup_free(d); 3206d5caef5bSAndrii Nakryiko return ERR_PTR(err); 3207d5caef5bSAndrii Nakryiko } 3208d5caef5bSAndrii Nakryiko 3209d5caef5bSAndrii Nakryiko return d; 3210d5caef5bSAndrii Nakryiko } 3211d5caef5bSAndrii Nakryiko 3212d5caef5bSAndrii Nakryiko /* 3213d5caef5bSAndrii Nakryiko * Iterate over all possible places in .BTF and .BTF.ext that can reference 3214d5caef5bSAndrii Nakryiko * string and pass pointer to it to a provided callback `fn`. 3215d5caef5bSAndrii Nakryiko */ 3216f36e99a4SAndrii Nakryiko static int btf_for_each_str_off(struct btf_dedup *d, str_off_visit_fn fn, void *ctx) 3217d5caef5bSAndrii Nakryiko { 3218f36e99a4SAndrii Nakryiko int i, r; 3219d5caef5bSAndrii Nakryiko 3220f86524efSAndrii Nakryiko for (i = 0; i < d->btf->nr_types; i++) { 3221f36e99a4SAndrii Nakryiko struct btf_type *t = btf_type_by_id(d->btf, d->btf->start_id + i); 3222f36e99a4SAndrii Nakryiko 3223f36e99a4SAndrii Nakryiko r = btf_type_visit_str_offs(t, fn, ctx); 3224d5caef5bSAndrii Nakryiko if (r) 3225d5caef5bSAndrii Nakryiko return r; 3226d5caef5bSAndrii Nakryiko } 3227d5caef5bSAndrii Nakryiko 3228d5caef5bSAndrii Nakryiko if (!d->btf_ext) 3229d5caef5bSAndrii Nakryiko return 0; 3230d5caef5bSAndrii Nakryiko 3231f36e99a4SAndrii Nakryiko r = btf_ext_visit_str_offs(d->btf_ext, fn, ctx); 3232d5caef5bSAndrii Nakryiko if (r) 3233d5caef5bSAndrii Nakryiko return r; 3234d5caef5bSAndrii Nakryiko 3235d5caef5bSAndrii Nakryiko return 0; 3236d5caef5bSAndrii Nakryiko } 3237d5caef5bSAndrii Nakryiko 323888a82c2aSAndrii Nakryiko static int strs_dedup_remap_str_off(__u32 *str_off_ptr, void *ctx) 3239d5caef5bSAndrii Nakryiko { 324088a82c2aSAndrii Nakryiko struct btf_dedup *d = ctx; 3241f86524efSAndrii Nakryiko __u32 str_off = *str_off_ptr; 324288a82c2aSAndrii Nakryiko const char *s; 324390d76d3eSAndrii Nakryiko int off, err; 3244d5caef5bSAndrii Nakryiko 3245f86524efSAndrii Nakryiko /* don't touch empty string or string in main BTF */ 3246f86524efSAndrii Nakryiko if (str_off == 0 || str_off < d->btf->start_str_off) 3247d5caef5bSAndrii Nakryiko return 0; 3248d5caef5bSAndrii Nakryiko 3249f86524efSAndrii Nakryiko s = btf__str_by_offset(d->btf, str_off); 3250f86524efSAndrii Nakryiko if (d->btf->base_btf) { 3251f86524efSAndrii Nakryiko err = btf__find_str(d->btf->base_btf, s); 3252f86524efSAndrii Nakryiko if (err >= 0) { 3253f86524efSAndrii Nakryiko *str_off_ptr = err; 3254f86524efSAndrii Nakryiko return 0; 3255f86524efSAndrii Nakryiko } 3256f86524efSAndrii Nakryiko if (err != -ENOENT) 3257f86524efSAndrii Nakryiko return err; 3258f86524efSAndrii Nakryiko } 3259f86524efSAndrii Nakryiko 326090d76d3eSAndrii Nakryiko off = strset__add_str(d->strs_set, s); 326190d76d3eSAndrii Nakryiko if (off < 0) 326290d76d3eSAndrii Nakryiko return off; 326388a82c2aSAndrii Nakryiko 326490d76d3eSAndrii Nakryiko *str_off_ptr = d->btf->start_str_off + off; 3265d5caef5bSAndrii Nakryiko return 0; 3266d5caef5bSAndrii Nakryiko } 3267d5caef5bSAndrii Nakryiko 3268d5caef5bSAndrii Nakryiko /* 3269d5caef5bSAndrii Nakryiko * Dedup string and filter out those that are not referenced from either .BTF 3270d5caef5bSAndrii Nakryiko * or .BTF.ext (if provided) sections. 3271d5caef5bSAndrii Nakryiko * 3272d5caef5bSAndrii Nakryiko * This is done by building index of all strings in BTF's string section, 3273d5caef5bSAndrii Nakryiko * then iterating over all entities that can reference strings (e.g., type 3274d5caef5bSAndrii Nakryiko * names, struct field names, .BTF.ext line info, etc) and marking corresponding 3275d5caef5bSAndrii Nakryiko * strings as used. After that all used strings are deduped and compacted into 3276d5caef5bSAndrii Nakryiko * sequential blob of memory and new offsets are calculated. Then all the string 3277d5caef5bSAndrii Nakryiko * references are iterated again and rewritten using new offsets. 3278d5caef5bSAndrii Nakryiko */ 3279d5caef5bSAndrii Nakryiko static int btf_dedup_strings(struct btf_dedup *d) 3280d5caef5bSAndrii Nakryiko { 328188a82c2aSAndrii Nakryiko int err; 3282d5caef5bSAndrii Nakryiko 3283919d2b1dSAndrii Nakryiko if (d->btf->strs_deduped) 3284919d2b1dSAndrii Nakryiko return 0; 3285919d2b1dSAndrii Nakryiko 328690d76d3eSAndrii Nakryiko d->strs_set = strset__new(BTF_MAX_STR_OFFSET, NULL, 0); 328790d76d3eSAndrii Nakryiko if (IS_ERR(d->strs_set)) { 328890d76d3eSAndrii Nakryiko err = PTR_ERR(d->strs_set); 328988a82c2aSAndrii Nakryiko goto err_out; 3290d5caef5bSAndrii Nakryiko } 3291d5caef5bSAndrii Nakryiko 3292f86524efSAndrii Nakryiko if (!d->btf->base_btf) { 329388a82c2aSAndrii Nakryiko /* insert empty string; we won't be looking it up during strings 329488a82c2aSAndrii Nakryiko * dedup, but it's good to have it for generic BTF string lookups 329588a82c2aSAndrii Nakryiko */ 329690d76d3eSAndrii Nakryiko err = strset__add_str(d->strs_set, ""); 329790d76d3eSAndrii Nakryiko if (err < 0) 329888a82c2aSAndrii Nakryiko goto err_out; 3299f86524efSAndrii Nakryiko } 3300d5caef5bSAndrii Nakryiko 3301d5caef5bSAndrii Nakryiko /* remap string offsets */ 330288a82c2aSAndrii Nakryiko err = btf_for_each_str_off(d, strs_dedup_remap_str_off, d); 3303d5caef5bSAndrii Nakryiko if (err) 330488a82c2aSAndrii Nakryiko goto err_out; 3305d5caef5bSAndrii Nakryiko 330688a82c2aSAndrii Nakryiko /* replace BTF string data and hash with deduped ones */ 330790d76d3eSAndrii Nakryiko strset__free(d->btf->strs_set); 330890d76d3eSAndrii Nakryiko d->btf->hdr->str_len = strset__data_size(d->strs_set); 330990d76d3eSAndrii Nakryiko d->btf->strs_set = d->strs_set; 331090d76d3eSAndrii Nakryiko d->strs_set = NULL; 3311919d2b1dSAndrii Nakryiko d->btf->strs_deduped = true; 331288a82c2aSAndrii Nakryiko return 0; 3313d5caef5bSAndrii Nakryiko 331488a82c2aSAndrii Nakryiko err_out: 331590d76d3eSAndrii Nakryiko strset__free(d->strs_set); 331690d76d3eSAndrii Nakryiko d->strs_set = NULL; 331788a82c2aSAndrii Nakryiko 3318d5caef5bSAndrii Nakryiko return err; 3319d5caef5bSAndrii Nakryiko } 3320d5caef5bSAndrii Nakryiko 33212fc3fc0bSAndrii Nakryiko static long btf_hash_common(struct btf_type *t) 3322d5caef5bSAndrii Nakryiko { 33232fc3fc0bSAndrii Nakryiko long h; 3324d5caef5bSAndrii Nakryiko 3325d5caef5bSAndrii Nakryiko h = hash_combine(0, t->name_off); 3326d5caef5bSAndrii Nakryiko h = hash_combine(h, t->info); 3327d5caef5bSAndrii Nakryiko h = hash_combine(h, t->size); 3328d5caef5bSAndrii Nakryiko return h; 3329d5caef5bSAndrii Nakryiko } 3330d5caef5bSAndrii Nakryiko 3331d5caef5bSAndrii Nakryiko static bool btf_equal_common(struct btf_type *t1, struct btf_type *t2) 3332d5caef5bSAndrii Nakryiko { 3333d5caef5bSAndrii Nakryiko return t1->name_off == t2->name_off && 3334d5caef5bSAndrii Nakryiko t1->info == t2->info && 3335d5caef5bSAndrii Nakryiko t1->size == t2->size; 3336d5caef5bSAndrii Nakryiko } 3337d5caef5bSAndrii Nakryiko 333830025e8bSYonghong Song /* Calculate type signature hash of INT or TAG. */ 3339223f903eSYonghong Song static long btf_hash_int_decl_tag(struct btf_type *t) 3340d5caef5bSAndrii Nakryiko { 3341d5caef5bSAndrii Nakryiko __u32 info = *(__u32 *)(t + 1); 33422fc3fc0bSAndrii Nakryiko long h; 3343d5caef5bSAndrii Nakryiko 3344d5caef5bSAndrii Nakryiko h = btf_hash_common(t); 3345d5caef5bSAndrii Nakryiko h = hash_combine(h, info); 3346d5caef5bSAndrii Nakryiko return h; 3347d5caef5bSAndrii Nakryiko } 3348d5caef5bSAndrii Nakryiko 334930025e8bSYonghong Song /* Check structural equality of two INTs or TAGs. */ 335030025e8bSYonghong Song static bool btf_equal_int_tag(struct btf_type *t1, struct btf_type *t2) 3351d5caef5bSAndrii Nakryiko { 3352d5caef5bSAndrii Nakryiko __u32 info1, info2; 3353d5caef5bSAndrii Nakryiko 3354d5caef5bSAndrii Nakryiko if (!btf_equal_common(t1, t2)) 3355d5caef5bSAndrii Nakryiko return false; 3356d5caef5bSAndrii Nakryiko info1 = *(__u32 *)(t1 + 1); 3357d5caef5bSAndrii Nakryiko info2 = *(__u32 *)(t2 + 1); 3358d5caef5bSAndrii Nakryiko return info1 == info2; 3359d5caef5bSAndrii Nakryiko } 3360d5caef5bSAndrii Nakryiko 3361d5caef5bSAndrii Nakryiko /* Calculate type signature hash of ENUM. */ 33622fc3fc0bSAndrii Nakryiko static long btf_hash_enum(struct btf_type *t) 3363d5caef5bSAndrii Nakryiko { 33642fc3fc0bSAndrii Nakryiko long h; 3365d5caef5bSAndrii Nakryiko 33669768095bSAndrii Nakryiko /* don't hash vlen and enum members to support enum fwd resolving */ 33679768095bSAndrii Nakryiko h = hash_combine(0, t->name_off); 33689768095bSAndrii Nakryiko h = hash_combine(h, t->info & ~0xffff); 33699768095bSAndrii Nakryiko h = hash_combine(h, t->size); 3370d5caef5bSAndrii Nakryiko return h; 3371d5caef5bSAndrii Nakryiko } 3372d5caef5bSAndrii Nakryiko 3373d5caef5bSAndrii Nakryiko /* Check structural equality of two ENUMs. */ 3374d5caef5bSAndrii Nakryiko static bool btf_equal_enum(struct btf_type *t1, struct btf_type *t2) 3375d5caef5bSAndrii Nakryiko { 3376b03bc685SAndrii Nakryiko const struct btf_enum *m1, *m2; 3377d5caef5bSAndrii Nakryiko __u16 vlen; 3378d5caef5bSAndrii Nakryiko int i; 3379d5caef5bSAndrii Nakryiko 3380d5caef5bSAndrii Nakryiko if (!btf_equal_common(t1, t2)) 3381d5caef5bSAndrii Nakryiko return false; 3382d5caef5bSAndrii Nakryiko 3383b03bc685SAndrii Nakryiko vlen = btf_vlen(t1); 3384b03bc685SAndrii Nakryiko m1 = btf_enum(t1); 3385b03bc685SAndrii Nakryiko m2 = btf_enum(t2); 3386d5caef5bSAndrii Nakryiko for (i = 0; i < vlen; i++) { 3387d5caef5bSAndrii Nakryiko if (m1->name_off != m2->name_off || m1->val != m2->val) 3388d5caef5bSAndrii Nakryiko return false; 3389d5caef5bSAndrii Nakryiko m1++; 3390d5caef5bSAndrii Nakryiko m2++; 3391d5caef5bSAndrii Nakryiko } 3392d5caef5bSAndrii Nakryiko return true; 3393d5caef5bSAndrii Nakryiko } 3394d5caef5bSAndrii Nakryiko 33959768095bSAndrii Nakryiko static inline bool btf_is_enum_fwd(struct btf_type *t) 33969768095bSAndrii Nakryiko { 3397b03bc685SAndrii Nakryiko return btf_is_enum(t) && btf_vlen(t) == 0; 33989768095bSAndrii Nakryiko } 33999768095bSAndrii Nakryiko 34009768095bSAndrii Nakryiko static bool btf_compat_enum(struct btf_type *t1, struct btf_type *t2) 34019768095bSAndrii Nakryiko { 34029768095bSAndrii Nakryiko if (!btf_is_enum_fwd(t1) && !btf_is_enum_fwd(t2)) 34039768095bSAndrii Nakryiko return btf_equal_enum(t1, t2); 34049768095bSAndrii Nakryiko /* ignore vlen when comparing */ 34059768095bSAndrii Nakryiko return t1->name_off == t2->name_off && 34069768095bSAndrii Nakryiko (t1->info & ~0xffff) == (t2->info & ~0xffff) && 34079768095bSAndrii Nakryiko t1->size == t2->size; 34089768095bSAndrii Nakryiko } 34099768095bSAndrii Nakryiko 3410d5caef5bSAndrii Nakryiko /* 3411d5caef5bSAndrii Nakryiko * Calculate type signature hash of STRUCT/UNION, ignoring referenced type IDs, 3412d5caef5bSAndrii Nakryiko * as referenced type IDs equivalence is established separately during type 3413d5caef5bSAndrii Nakryiko * graph equivalence check algorithm. 3414d5caef5bSAndrii Nakryiko */ 34152fc3fc0bSAndrii Nakryiko static long btf_hash_struct(struct btf_type *t) 3416d5caef5bSAndrii Nakryiko { 3417b03bc685SAndrii Nakryiko const struct btf_member *member = btf_members(t); 3418b03bc685SAndrii Nakryiko __u32 vlen = btf_vlen(t); 34192fc3fc0bSAndrii Nakryiko long h = btf_hash_common(t); 3420d5caef5bSAndrii Nakryiko int i; 3421d5caef5bSAndrii Nakryiko 3422d5caef5bSAndrii Nakryiko for (i = 0; i < vlen; i++) { 3423d5caef5bSAndrii Nakryiko h = hash_combine(h, member->name_off); 3424d5caef5bSAndrii Nakryiko h = hash_combine(h, member->offset); 3425d5caef5bSAndrii Nakryiko /* no hashing of referenced type ID, it can be unresolved yet */ 3426d5caef5bSAndrii Nakryiko member++; 3427d5caef5bSAndrii Nakryiko } 3428d5caef5bSAndrii Nakryiko return h; 3429d5caef5bSAndrii Nakryiko } 3430d5caef5bSAndrii Nakryiko 3431d5caef5bSAndrii Nakryiko /* 3432d5caef5bSAndrii Nakryiko * Check structural compatibility of two FUNC_PROTOs, ignoring referenced type 3433d5caef5bSAndrii Nakryiko * IDs. This check is performed during type graph equivalence check and 3434d5caef5bSAndrii Nakryiko * referenced types equivalence is checked separately. 3435d5caef5bSAndrii Nakryiko */ 343691097fbeSAndrii Nakryiko static bool btf_shallow_equal_struct(struct btf_type *t1, struct btf_type *t2) 3437d5caef5bSAndrii Nakryiko { 3438b03bc685SAndrii Nakryiko const struct btf_member *m1, *m2; 3439d5caef5bSAndrii Nakryiko __u16 vlen; 3440d5caef5bSAndrii Nakryiko int i; 3441d5caef5bSAndrii Nakryiko 3442d5caef5bSAndrii Nakryiko if (!btf_equal_common(t1, t2)) 3443d5caef5bSAndrii Nakryiko return false; 3444d5caef5bSAndrii Nakryiko 3445b03bc685SAndrii Nakryiko vlen = btf_vlen(t1); 3446b03bc685SAndrii Nakryiko m1 = btf_members(t1); 3447b03bc685SAndrii Nakryiko m2 = btf_members(t2); 3448d5caef5bSAndrii Nakryiko for (i = 0; i < vlen; i++) { 3449d5caef5bSAndrii Nakryiko if (m1->name_off != m2->name_off || m1->offset != m2->offset) 3450d5caef5bSAndrii Nakryiko return false; 3451d5caef5bSAndrii Nakryiko m1++; 3452d5caef5bSAndrii Nakryiko m2++; 3453d5caef5bSAndrii Nakryiko } 3454d5caef5bSAndrii Nakryiko return true; 3455d5caef5bSAndrii Nakryiko } 3456d5caef5bSAndrii Nakryiko 3457d5caef5bSAndrii Nakryiko /* 3458d5caef5bSAndrii Nakryiko * Calculate type signature hash of ARRAY, including referenced type IDs, 3459d5caef5bSAndrii Nakryiko * under assumption that they were already resolved to canonical type IDs and 3460d5caef5bSAndrii Nakryiko * are not going to change. 3461d5caef5bSAndrii Nakryiko */ 34622fc3fc0bSAndrii Nakryiko static long btf_hash_array(struct btf_type *t) 3463d5caef5bSAndrii Nakryiko { 3464b03bc685SAndrii Nakryiko const struct btf_array *info = btf_array(t); 34652fc3fc0bSAndrii Nakryiko long h = btf_hash_common(t); 3466d5caef5bSAndrii Nakryiko 3467d5caef5bSAndrii Nakryiko h = hash_combine(h, info->type); 3468d5caef5bSAndrii Nakryiko h = hash_combine(h, info->index_type); 3469d5caef5bSAndrii Nakryiko h = hash_combine(h, info->nelems); 3470d5caef5bSAndrii Nakryiko return h; 3471d5caef5bSAndrii Nakryiko } 3472d5caef5bSAndrii Nakryiko 3473d5caef5bSAndrii Nakryiko /* 3474d5caef5bSAndrii Nakryiko * Check exact equality of two ARRAYs, taking into account referenced 3475d5caef5bSAndrii Nakryiko * type IDs, under assumption that they were already resolved to canonical 3476d5caef5bSAndrii Nakryiko * type IDs and are not going to change. 3477d5caef5bSAndrii Nakryiko * This function is called during reference types deduplication to compare 3478d5caef5bSAndrii Nakryiko * ARRAY to potential canonical representative. 3479d5caef5bSAndrii Nakryiko */ 3480d5caef5bSAndrii Nakryiko static bool btf_equal_array(struct btf_type *t1, struct btf_type *t2) 3481d5caef5bSAndrii Nakryiko { 3482b03bc685SAndrii Nakryiko const struct btf_array *info1, *info2; 3483d5caef5bSAndrii Nakryiko 3484d5caef5bSAndrii Nakryiko if (!btf_equal_common(t1, t2)) 3485d5caef5bSAndrii Nakryiko return false; 3486d5caef5bSAndrii Nakryiko 3487b03bc685SAndrii Nakryiko info1 = btf_array(t1); 3488b03bc685SAndrii Nakryiko info2 = btf_array(t2); 3489d5caef5bSAndrii Nakryiko return info1->type == info2->type && 3490d5caef5bSAndrii Nakryiko info1->index_type == info2->index_type && 3491d5caef5bSAndrii Nakryiko info1->nelems == info2->nelems; 3492d5caef5bSAndrii Nakryiko } 3493d5caef5bSAndrii Nakryiko 3494d5caef5bSAndrii Nakryiko /* 3495d5caef5bSAndrii Nakryiko * Check structural compatibility of two ARRAYs, ignoring referenced type 3496d5caef5bSAndrii Nakryiko * IDs. This check is performed during type graph equivalence check and 3497d5caef5bSAndrii Nakryiko * referenced types equivalence is checked separately. 3498d5caef5bSAndrii Nakryiko */ 3499d5caef5bSAndrii Nakryiko static bool btf_compat_array(struct btf_type *t1, struct btf_type *t2) 3500d5caef5bSAndrii Nakryiko { 3501d5caef5bSAndrii Nakryiko if (!btf_equal_common(t1, t2)) 3502d5caef5bSAndrii Nakryiko return false; 3503d5caef5bSAndrii Nakryiko 3504b03bc685SAndrii Nakryiko return btf_array(t1)->nelems == btf_array(t2)->nelems; 3505d5caef5bSAndrii Nakryiko } 3506d5caef5bSAndrii Nakryiko 3507d5caef5bSAndrii Nakryiko /* 3508d5caef5bSAndrii Nakryiko * Calculate type signature hash of FUNC_PROTO, including referenced type IDs, 3509d5caef5bSAndrii Nakryiko * under assumption that they were already resolved to canonical type IDs and 3510d5caef5bSAndrii Nakryiko * are not going to change. 3511d5caef5bSAndrii Nakryiko */ 35122fc3fc0bSAndrii Nakryiko static long btf_hash_fnproto(struct btf_type *t) 3513d5caef5bSAndrii Nakryiko { 3514b03bc685SAndrii Nakryiko const struct btf_param *member = btf_params(t); 3515b03bc685SAndrii Nakryiko __u16 vlen = btf_vlen(t); 35162fc3fc0bSAndrii Nakryiko long h = btf_hash_common(t); 3517d5caef5bSAndrii Nakryiko int i; 3518d5caef5bSAndrii Nakryiko 3519d5caef5bSAndrii Nakryiko for (i = 0; i < vlen; i++) { 3520d5caef5bSAndrii Nakryiko h = hash_combine(h, member->name_off); 3521d5caef5bSAndrii Nakryiko h = hash_combine(h, member->type); 3522d5caef5bSAndrii Nakryiko member++; 3523d5caef5bSAndrii Nakryiko } 3524d5caef5bSAndrii Nakryiko return h; 3525d5caef5bSAndrii Nakryiko } 3526d5caef5bSAndrii Nakryiko 3527d5caef5bSAndrii Nakryiko /* 3528d5caef5bSAndrii Nakryiko * Check exact equality of two FUNC_PROTOs, taking into account referenced 3529d5caef5bSAndrii Nakryiko * type IDs, under assumption that they were already resolved to canonical 3530d5caef5bSAndrii Nakryiko * type IDs and are not going to change. 3531d5caef5bSAndrii Nakryiko * This function is called during reference types deduplication to compare 3532d5caef5bSAndrii Nakryiko * FUNC_PROTO to potential canonical representative. 3533d5caef5bSAndrii Nakryiko */ 35342fc3fc0bSAndrii Nakryiko static bool btf_equal_fnproto(struct btf_type *t1, struct btf_type *t2) 3535d5caef5bSAndrii Nakryiko { 3536b03bc685SAndrii Nakryiko const struct btf_param *m1, *m2; 3537d5caef5bSAndrii Nakryiko __u16 vlen; 3538d5caef5bSAndrii Nakryiko int i; 3539d5caef5bSAndrii Nakryiko 3540d5caef5bSAndrii Nakryiko if (!btf_equal_common(t1, t2)) 3541d5caef5bSAndrii Nakryiko return false; 3542d5caef5bSAndrii Nakryiko 3543b03bc685SAndrii Nakryiko vlen = btf_vlen(t1); 3544b03bc685SAndrii Nakryiko m1 = btf_params(t1); 3545b03bc685SAndrii Nakryiko m2 = btf_params(t2); 3546d5caef5bSAndrii Nakryiko for (i = 0; i < vlen; i++) { 3547d5caef5bSAndrii Nakryiko if (m1->name_off != m2->name_off || m1->type != m2->type) 3548d5caef5bSAndrii Nakryiko return false; 3549d5caef5bSAndrii Nakryiko m1++; 3550d5caef5bSAndrii Nakryiko m2++; 3551d5caef5bSAndrii Nakryiko } 3552d5caef5bSAndrii Nakryiko return true; 3553d5caef5bSAndrii Nakryiko } 3554d5caef5bSAndrii Nakryiko 3555d5caef5bSAndrii Nakryiko /* 3556d5caef5bSAndrii Nakryiko * Check structural compatibility of two FUNC_PROTOs, ignoring referenced type 3557d5caef5bSAndrii Nakryiko * IDs. This check is performed during type graph equivalence check and 3558d5caef5bSAndrii Nakryiko * referenced types equivalence is checked separately. 3559d5caef5bSAndrii Nakryiko */ 35602fc3fc0bSAndrii Nakryiko static bool btf_compat_fnproto(struct btf_type *t1, struct btf_type *t2) 3561d5caef5bSAndrii Nakryiko { 3562b03bc685SAndrii Nakryiko const struct btf_param *m1, *m2; 3563d5caef5bSAndrii Nakryiko __u16 vlen; 3564d5caef5bSAndrii Nakryiko int i; 3565d5caef5bSAndrii Nakryiko 3566d5caef5bSAndrii Nakryiko /* skip return type ID */ 3567d5caef5bSAndrii Nakryiko if (t1->name_off != t2->name_off || t1->info != t2->info) 3568d5caef5bSAndrii Nakryiko return false; 3569d5caef5bSAndrii Nakryiko 3570b03bc685SAndrii Nakryiko vlen = btf_vlen(t1); 3571b03bc685SAndrii Nakryiko m1 = btf_params(t1); 3572b03bc685SAndrii Nakryiko m2 = btf_params(t2); 3573d5caef5bSAndrii Nakryiko for (i = 0; i < vlen; i++) { 3574d5caef5bSAndrii Nakryiko if (m1->name_off != m2->name_off) 3575d5caef5bSAndrii Nakryiko return false; 3576d5caef5bSAndrii Nakryiko m1++; 3577d5caef5bSAndrii Nakryiko m2++; 3578d5caef5bSAndrii Nakryiko } 3579d5caef5bSAndrii Nakryiko return true; 3580d5caef5bSAndrii Nakryiko } 3581d5caef5bSAndrii Nakryiko 3582f86524efSAndrii Nakryiko /* Prepare split BTF for deduplication by calculating hashes of base BTF's 3583f86524efSAndrii Nakryiko * types and initializing the rest of the state (canonical type mapping) for 3584f86524efSAndrii Nakryiko * the fixed base BTF part. 3585f86524efSAndrii Nakryiko */ 3586f86524efSAndrii Nakryiko static int btf_dedup_prep(struct btf_dedup *d) 3587f86524efSAndrii Nakryiko { 3588f86524efSAndrii Nakryiko struct btf_type *t; 3589f86524efSAndrii Nakryiko int type_id; 3590f86524efSAndrii Nakryiko long h; 3591f86524efSAndrii Nakryiko 3592f86524efSAndrii Nakryiko if (!d->btf->base_btf) 3593f86524efSAndrii Nakryiko return 0; 3594f86524efSAndrii Nakryiko 3595f86524efSAndrii Nakryiko for (type_id = 1; type_id < d->btf->start_id; type_id++) { 3596f86524efSAndrii Nakryiko t = btf_type_by_id(d->btf, type_id); 3597f86524efSAndrii Nakryiko 3598f86524efSAndrii Nakryiko /* all base BTF types are self-canonical by definition */ 3599f86524efSAndrii Nakryiko d->map[type_id] = type_id; 3600f86524efSAndrii Nakryiko 3601f86524efSAndrii Nakryiko switch (btf_kind(t)) { 3602f86524efSAndrii Nakryiko case BTF_KIND_VAR: 3603f86524efSAndrii Nakryiko case BTF_KIND_DATASEC: 3604f86524efSAndrii Nakryiko /* VAR and DATASEC are never hash/deduplicated */ 3605f86524efSAndrii Nakryiko continue; 3606f86524efSAndrii Nakryiko case BTF_KIND_CONST: 3607f86524efSAndrii Nakryiko case BTF_KIND_VOLATILE: 3608f86524efSAndrii Nakryiko case BTF_KIND_RESTRICT: 3609f86524efSAndrii Nakryiko case BTF_KIND_PTR: 3610f86524efSAndrii Nakryiko case BTF_KIND_FWD: 3611f86524efSAndrii Nakryiko case BTF_KIND_TYPEDEF: 3612f86524efSAndrii Nakryiko case BTF_KIND_FUNC: 361322541a9eSIlya Leoshkevich case BTF_KIND_FLOAT: 3614f86524efSAndrii Nakryiko h = btf_hash_common(t); 3615f86524efSAndrii Nakryiko break; 3616f86524efSAndrii Nakryiko case BTF_KIND_INT: 3617223f903eSYonghong Song case BTF_KIND_DECL_TAG: 3618223f903eSYonghong Song h = btf_hash_int_decl_tag(t); 3619f86524efSAndrii Nakryiko break; 3620f86524efSAndrii Nakryiko case BTF_KIND_ENUM: 3621f86524efSAndrii Nakryiko h = btf_hash_enum(t); 3622f86524efSAndrii Nakryiko break; 3623f86524efSAndrii Nakryiko case BTF_KIND_STRUCT: 3624f86524efSAndrii Nakryiko case BTF_KIND_UNION: 3625f86524efSAndrii Nakryiko h = btf_hash_struct(t); 3626f86524efSAndrii Nakryiko break; 3627f86524efSAndrii Nakryiko case BTF_KIND_ARRAY: 3628f86524efSAndrii Nakryiko h = btf_hash_array(t); 3629f86524efSAndrii Nakryiko break; 3630f86524efSAndrii Nakryiko case BTF_KIND_FUNC_PROTO: 3631f86524efSAndrii Nakryiko h = btf_hash_fnproto(t); 3632f86524efSAndrii Nakryiko break; 3633f86524efSAndrii Nakryiko default: 3634f86524efSAndrii Nakryiko pr_debug("unknown kind %d for type [%d]\n", btf_kind(t), type_id); 3635f86524efSAndrii Nakryiko return -EINVAL; 3636f86524efSAndrii Nakryiko } 3637f86524efSAndrii Nakryiko if (btf_dedup_table_add(d, h, type_id)) 3638f86524efSAndrii Nakryiko return -ENOMEM; 3639f86524efSAndrii Nakryiko } 3640f86524efSAndrii Nakryiko 3641f86524efSAndrii Nakryiko return 0; 3642f86524efSAndrii Nakryiko } 3643f86524efSAndrii Nakryiko 3644d5caef5bSAndrii Nakryiko /* 3645d5caef5bSAndrii Nakryiko * Deduplicate primitive types, that can't reference other types, by calculating 3646d5caef5bSAndrii Nakryiko * their type signature hash and comparing them with any possible canonical 3647d5caef5bSAndrii Nakryiko * candidate. If no canonical candidate matches, type itself is marked as 3648d5caef5bSAndrii Nakryiko * canonical and is added into `btf_dedup->dedup_table` as another candidate. 3649d5caef5bSAndrii Nakryiko */ 3650d5caef5bSAndrii Nakryiko static int btf_dedup_prim_type(struct btf_dedup *d, __u32 type_id) 3651d5caef5bSAndrii Nakryiko { 3652740e69c3SAndrii Nakryiko struct btf_type *t = btf_type_by_id(d->btf, type_id); 36532fc3fc0bSAndrii Nakryiko struct hashmap_entry *hash_entry; 3654d5caef5bSAndrii Nakryiko struct btf_type *cand; 3655d5caef5bSAndrii Nakryiko /* if we don't find equivalent type, then we are canonical */ 3656d5caef5bSAndrii Nakryiko __u32 new_id = type_id; 36572fc3fc0bSAndrii Nakryiko __u32 cand_id; 36582fc3fc0bSAndrii Nakryiko long h; 3659d5caef5bSAndrii Nakryiko 3660b03bc685SAndrii Nakryiko switch (btf_kind(t)) { 3661d5caef5bSAndrii Nakryiko case BTF_KIND_CONST: 3662d5caef5bSAndrii Nakryiko case BTF_KIND_VOLATILE: 3663d5caef5bSAndrii Nakryiko case BTF_KIND_RESTRICT: 3664d5caef5bSAndrii Nakryiko case BTF_KIND_PTR: 3665d5caef5bSAndrii Nakryiko case BTF_KIND_TYPEDEF: 3666d5caef5bSAndrii Nakryiko case BTF_KIND_ARRAY: 3667d5caef5bSAndrii Nakryiko case BTF_KIND_STRUCT: 3668d5caef5bSAndrii Nakryiko case BTF_KIND_UNION: 3669d5caef5bSAndrii Nakryiko case BTF_KIND_FUNC: 3670d5caef5bSAndrii Nakryiko case BTF_KIND_FUNC_PROTO: 3671189cf5a4SAndrii Nakryiko case BTF_KIND_VAR: 3672189cf5a4SAndrii Nakryiko case BTF_KIND_DATASEC: 3673223f903eSYonghong Song case BTF_KIND_DECL_TAG: 3674d5caef5bSAndrii Nakryiko return 0; 3675d5caef5bSAndrii Nakryiko 3676d5caef5bSAndrii Nakryiko case BTF_KIND_INT: 3677223f903eSYonghong Song h = btf_hash_int_decl_tag(t); 36782fc3fc0bSAndrii Nakryiko for_each_dedup_cand(d, hash_entry, h) { 36792fc3fc0bSAndrii Nakryiko cand_id = (__u32)(long)hash_entry->value; 3680740e69c3SAndrii Nakryiko cand = btf_type_by_id(d->btf, cand_id); 368130025e8bSYonghong Song if (btf_equal_int_tag(t, cand)) { 36822fc3fc0bSAndrii Nakryiko new_id = cand_id; 3683d5caef5bSAndrii Nakryiko break; 3684d5caef5bSAndrii Nakryiko } 3685d5caef5bSAndrii Nakryiko } 3686d5caef5bSAndrii Nakryiko break; 3687d5caef5bSAndrii Nakryiko 3688d5caef5bSAndrii Nakryiko case BTF_KIND_ENUM: 3689d5caef5bSAndrii Nakryiko h = btf_hash_enum(t); 36902fc3fc0bSAndrii Nakryiko for_each_dedup_cand(d, hash_entry, h) { 36912fc3fc0bSAndrii Nakryiko cand_id = (__u32)(long)hash_entry->value; 3692740e69c3SAndrii Nakryiko cand = btf_type_by_id(d->btf, cand_id); 3693d5caef5bSAndrii Nakryiko if (btf_equal_enum(t, cand)) { 36942fc3fc0bSAndrii Nakryiko new_id = cand_id; 3695d5caef5bSAndrii Nakryiko break; 3696d5caef5bSAndrii Nakryiko } 36979768095bSAndrii Nakryiko if (d->opts.dont_resolve_fwds) 36989768095bSAndrii Nakryiko continue; 36999768095bSAndrii Nakryiko if (btf_compat_enum(t, cand)) { 37009768095bSAndrii Nakryiko if (btf_is_enum_fwd(t)) { 37019768095bSAndrii Nakryiko /* resolve fwd to full enum */ 37022fc3fc0bSAndrii Nakryiko new_id = cand_id; 37039768095bSAndrii Nakryiko break; 37049768095bSAndrii Nakryiko } 37059768095bSAndrii Nakryiko /* resolve canonical enum fwd to full enum */ 37062fc3fc0bSAndrii Nakryiko d->map[cand_id] = type_id; 37079768095bSAndrii Nakryiko } 3708d5caef5bSAndrii Nakryiko } 3709d5caef5bSAndrii Nakryiko break; 3710d5caef5bSAndrii Nakryiko 3711d5caef5bSAndrii Nakryiko case BTF_KIND_FWD: 371222541a9eSIlya Leoshkevich case BTF_KIND_FLOAT: 3713d5caef5bSAndrii Nakryiko h = btf_hash_common(t); 37142fc3fc0bSAndrii Nakryiko for_each_dedup_cand(d, hash_entry, h) { 37152fc3fc0bSAndrii Nakryiko cand_id = (__u32)(long)hash_entry->value; 3716740e69c3SAndrii Nakryiko cand = btf_type_by_id(d->btf, cand_id); 3717d5caef5bSAndrii Nakryiko if (btf_equal_common(t, cand)) { 37182fc3fc0bSAndrii Nakryiko new_id = cand_id; 3719d5caef5bSAndrii Nakryiko break; 3720d5caef5bSAndrii Nakryiko } 3721d5caef5bSAndrii Nakryiko } 3722d5caef5bSAndrii Nakryiko break; 3723d5caef5bSAndrii Nakryiko 3724d5caef5bSAndrii Nakryiko default: 3725d5caef5bSAndrii Nakryiko return -EINVAL; 3726d5caef5bSAndrii Nakryiko } 3727d5caef5bSAndrii Nakryiko 3728d5caef5bSAndrii Nakryiko d->map[type_id] = new_id; 3729d5caef5bSAndrii Nakryiko if (type_id == new_id && btf_dedup_table_add(d, h, type_id)) 3730d5caef5bSAndrii Nakryiko return -ENOMEM; 3731d5caef5bSAndrii Nakryiko 3732d5caef5bSAndrii Nakryiko return 0; 3733d5caef5bSAndrii Nakryiko } 3734d5caef5bSAndrii Nakryiko 3735d5caef5bSAndrii Nakryiko static int btf_dedup_prim_types(struct btf_dedup *d) 3736d5caef5bSAndrii Nakryiko { 3737d5caef5bSAndrii Nakryiko int i, err; 3738d5caef5bSAndrii Nakryiko 3739f86524efSAndrii Nakryiko for (i = 0; i < d->btf->nr_types; i++) { 3740f86524efSAndrii Nakryiko err = btf_dedup_prim_type(d, d->btf->start_id + i); 3741d5caef5bSAndrii Nakryiko if (err) 3742d5caef5bSAndrii Nakryiko return err; 3743d5caef5bSAndrii Nakryiko } 3744d5caef5bSAndrii Nakryiko return 0; 3745d5caef5bSAndrii Nakryiko } 3746d5caef5bSAndrii Nakryiko 3747d5caef5bSAndrii Nakryiko /* 3748d5caef5bSAndrii Nakryiko * Check whether type is already mapped into canonical one (could be to itself). 3749d5caef5bSAndrii Nakryiko */ 3750d5caef5bSAndrii Nakryiko static inline bool is_type_mapped(struct btf_dedup *d, uint32_t type_id) 3751d5caef5bSAndrii Nakryiko { 37525aab392cSAndrii Nakryiko return d->map[type_id] <= BTF_MAX_NR_TYPES; 3753d5caef5bSAndrii Nakryiko } 3754d5caef5bSAndrii Nakryiko 3755d5caef5bSAndrii Nakryiko /* 3756d5caef5bSAndrii Nakryiko * Resolve type ID into its canonical type ID, if any; otherwise return original 3757d5caef5bSAndrii Nakryiko * type ID. If type is FWD and is resolved into STRUCT/UNION already, follow 3758d5caef5bSAndrii Nakryiko * STRUCT/UNION link and resolve it into canonical type ID as well. 3759d5caef5bSAndrii Nakryiko */ 3760d5caef5bSAndrii Nakryiko static inline __u32 resolve_type_id(struct btf_dedup *d, __u32 type_id) 3761d5caef5bSAndrii Nakryiko { 3762d5caef5bSAndrii Nakryiko while (is_type_mapped(d, type_id) && d->map[type_id] != type_id) 3763d5caef5bSAndrii Nakryiko type_id = d->map[type_id]; 3764d5caef5bSAndrii Nakryiko return type_id; 3765d5caef5bSAndrii Nakryiko } 3766d5caef5bSAndrii Nakryiko 3767d5caef5bSAndrii Nakryiko /* 3768d5caef5bSAndrii Nakryiko * Resolve FWD to underlying STRUCT/UNION, if any; otherwise return original 3769d5caef5bSAndrii Nakryiko * type ID. 3770d5caef5bSAndrii Nakryiko */ 3771d5caef5bSAndrii Nakryiko static uint32_t resolve_fwd_id(struct btf_dedup *d, uint32_t type_id) 3772d5caef5bSAndrii Nakryiko { 3773d5caef5bSAndrii Nakryiko __u32 orig_type_id = type_id; 3774d5caef5bSAndrii Nakryiko 3775740e69c3SAndrii Nakryiko if (!btf_is_fwd(btf__type_by_id(d->btf, type_id))) 3776d5caef5bSAndrii Nakryiko return type_id; 3777d5caef5bSAndrii Nakryiko 3778d5caef5bSAndrii Nakryiko while (is_type_mapped(d, type_id) && d->map[type_id] != type_id) 3779d5caef5bSAndrii Nakryiko type_id = d->map[type_id]; 3780d5caef5bSAndrii Nakryiko 3781740e69c3SAndrii Nakryiko if (!btf_is_fwd(btf__type_by_id(d->btf, type_id))) 3782d5caef5bSAndrii Nakryiko return type_id; 3783d5caef5bSAndrii Nakryiko 3784d5caef5bSAndrii Nakryiko return orig_type_id; 3785d5caef5bSAndrii Nakryiko } 3786d5caef5bSAndrii Nakryiko 3787d5caef5bSAndrii Nakryiko 3788d5caef5bSAndrii Nakryiko static inline __u16 btf_fwd_kind(struct btf_type *t) 3789d5caef5bSAndrii Nakryiko { 3790b03bc685SAndrii Nakryiko return btf_kflag(t) ? BTF_KIND_UNION : BTF_KIND_STRUCT; 3791d5caef5bSAndrii Nakryiko } 3792d5caef5bSAndrii Nakryiko 37936b6e6b1dSAndrii Nakryiko /* Check if given two types are identical ARRAY definitions */ 37946b6e6b1dSAndrii Nakryiko static int btf_dedup_identical_arrays(struct btf_dedup *d, __u32 id1, __u32 id2) 37956b6e6b1dSAndrii Nakryiko { 37966b6e6b1dSAndrii Nakryiko struct btf_type *t1, *t2; 37976b6e6b1dSAndrii Nakryiko 37986b6e6b1dSAndrii Nakryiko t1 = btf_type_by_id(d->btf, id1); 37996b6e6b1dSAndrii Nakryiko t2 = btf_type_by_id(d->btf, id2); 38006b6e6b1dSAndrii Nakryiko if (!btf_is_array(t1) || !btf_is_array(t2)) 38016b6e6b1dSAndrii Nakryiko return 0; 38026b6e6b1dSAndrii Nakryiko 38036b6e6b1dSAndrii Nakryiko return btf_equal_array(t1, t2); 38046b6e6b1dSAndrii Nakryiko } 38056b6e6b1dSAndrii Nakryiko 3806d5caef5bSAndrii Nakryiko /* 3807d5caef5bSAndrii Nakryiko * Check equivalence of BTF type graph formed by candidate struct/union (we'll 3808d5caef5bSAndrii Nakryiko * call it "candidate graph" in this description for brevity) to a type graph 3809d5caef5bSAndrii Nakryiko * formed by (potential) canonical struct/union ("canonical graph" for brevity 3810d5caef5bSAndrii Nakryiko * here, though keep in mind that not all types in canonical graph are 3811d5caef5bSAndrii Nakryiko * necessarily canonical representatives themselves, some of them might be 3812d5caef5bSAndrii Nakryiko * duplicates or its uniqueness might not have been established yet). 3813d5caef5bSAndrii Nakryiko * Returns: 3814d5caef5bSAndrii Nakryiko * - >0, if type graphs are equivalent; 3815d5caef5bSAndrii Nakryiko * - 0, if not equivalent; 3816d5caef5bSAndrii Nakryiko * - <0, on error. 3817d5caef5bSAndrii Nakryiko * 3818d5caef5bSAndrii Nakryiko * Algorithm performs side-by-side DFS traversal of both type graphs and checks 3819d5caef5bSAndrii Nakryiko * equivalence of BTF types at each step. If at any point BTF types in candidate 3820d5caef5bSAndrii Nakryiko * and canonical graphs are not compatible structurally, whole graphs are 3821d5caef5bSAndrii Nakryiko * incompatible. If types are structurally equivalent (i.e., all information 3822d5caef5bSAndrii Nakryiko * except referenced type IDs is exactly the same), a mapping from `canon_id` to 3823d5caef5bSAndrii Nakryiko * a `cand_id` is recored in hypothetical mapping (`btf_dedup->hypot_map`). 3824d5caef5bSAndrii Nakryiko * If a type references other types, then those referenced types are checked 3825d5caef5bSAndrii Nakryiko * for equivalence recursively. 3826d5caef5bSAndrii Nakryiko * 3827d5caef5bSAndrii Nakryiko * During DFS traversal, if we find that for current `canon_id` type we 3828d5caef5bSAndrii Nakryiko * already have some mapping in hypothetical map, we check for two possible 3829d5caef5bSAndrii Nakryiko * situations: 3830d5caef5bSAndrii Nakryiko * - `canon_id` is mapped to exactly the same type as `cand_id`. This will 3831d5caef5bSAndrii Nakryiko * happen when type graphs have cycles. In this case we assume those two 3832d5caef5bSAndrii Nakryiko * types are equivalent. 3833d5caef5bSAndrii Nakryiko * - `canon_id` is mapped to different type. This is contradiction in our 3834d5caef5bSAndrii Nakryiko * hypothetical mapping, because same graph in canonical graph corresponds 3835d5caef5bSAndrii Nakryiko * to two different types in candidate graph, which for equivalent type 3836d5caef5bSAndrii Nakryiko * graphs shouldn't happen. This condition terminates equivalence check 3837d5caef5bSAndrii Nakryiko * with negative result. 3838d5caef5bSAndrii Nakryiko * 3839d5caef5bSAndrii Nakryiko * If type graphs traversal exhausts types to check and find no contradiction, 3840d5caef5bSAndrii Nakryiko * then type graphs are equivalent. 3841d5caef5bSAndrii Nakryiko * 3842d5caef5bSAndrii Nakryiko * When checking types for equivalence, there is one special case: FWD types. 3843d5caef5bSAndrii Nakryiko * If FWD type resolution is allowed and one of the types (either from canonical 3844d5caef5bSAndrii Nakryiko * or candidate graph) is FWD and other is STRUCT/UNION (depending on FWD's kind 3845d5caef5bSAndrii Nakryiko * flag) and their names match, hypothetical mapping is updated to point from 3846d5caef5bSAndrii Nakryiko * FWD to STRUCT/UNION. If graphs will be determined as equivalent successfully, 3847d5caef5bSAndrii Nakryiko * this mapping will be used to record FWD -> STRUCT/UNION mapping permanently. 3848d5caef5bSAndrii Nakryiko * 3849d5caef5bSAndrii Nakryiko * Technically, this could lead to incorrect FWD to STRUCT/UNION resolution, 3850d5caef5bSAndrii Nakryiko * if there are two exactly named (or anonymous) structs/unions that are 3851d5caef5bSAndrii Nakryiko * compatible structurally, one of which has FWD field, while other is concrete 3852d5caef5bSAndrii Nakryiko * STRUCT/UNION, but according to C sources they are different structs/unions 3853d5caef5bSAndrii Nakryiko * that are referencing different types with the same name. This is extremely 3854d5caef5bSAndrii Nakryiko * unlikely to happen, but btf_dedup API allows to disable FWD resolution if 3855d5caef5bSAndrii Nakryiko * this logic is causing problems. 3856d5caef5bSAndrii Nakryiko * 3857d5caef5bSAndrii Nakryiko * Doing FWD resolution means that both candidate and/or canonical graphs can 3858d5caef5bSAndrii Nakryiko * consists of portions of the graph that come from multiple compilation units. 3859d5caef5bSAndrii Nakryiko * This is due to the fact that types within single compilation unit are always 3860d5caef5bSAndrii Nakryiko * deduplicated and FWDs are already resolved, if referenced struct/union 3861d5caef5bSAndrii Nakryiko * definiton is available. So, if we had unresolved FWD and found corresponding 3862d5caef5bSAndrii Nakryiko * STRUCT/UNION, they will be from different compilation units. This 3863d5caef5bSAndrii Nakryiko * consequently means that when we "link" FWD to corresponding STRUCT/UNION, 3864d5caef5bSAndrii Nakryiko * type graph will likely have at least two different BTF types that describe 3865d5caef5bSAndrii Nakryiko * same type (e.g., most probably there will be two different BTF types for the 3866d5caef5bSAndrii Nakryiko * same 'int' primitive type) and could even have "overlapping" parts of type 3867d5caef5bSAndrii Nakryiko * graph that describe same subset of types. 3868d5caef5bSAndrii Nakryiko * 3869d5caef5bSAndrii Nakryiko * This in turn means that our assumption that each type in canonical graph 3870d5caef5bSAndrii Nakryiko * must correspond to exactly one type in candidate graph might not hold 3871d5caef5bSAndrii Nakryiko * anymore and will make it harder to detect contradictions using hypothetical 3872d5caef5bSAndrii Nakryiko * map. To handle this problem, we allow to follow FWD -> STRUCT/UNION 3873d5caef5bSAndrii Nakryiko * resolution only in canonical graph. FWDs in candidate graphs are never 3874d5caef5bSAndrii Nakryiko * resolved. To see why it's OK, let's check all possible situations w.r.t. FWDs 3875d5caef5bSAndrii Nakryiko * that can occur: 3876d5caef5bSAndrii Nakryiko * - Both types in canonical and candidate graphs are FWDs. If they are 3877d5caef5bSAndrii Nakryiko * structurally equivalent, then they can either be both resolved to the 3878d5caef5bSAndrii Nakryiko * same STRUCT/UNION or not resolved at all. In both cases they are 3879d5caef5bSAndrii Nakryiko * equivalent and there is no need to resolve FWD on candidate side. 3880d5caef5bSAndrii Nakryiko * - Both types in canonical and candidate graphs are concrete STRUCT/UNION, 3881d5caef5bSAndrii Nakryiko * so nothing to resolve as well, algorithm will check equivalence anyway. 3882d5caef5bSAndrii Nakryiko * - Type in canonical graph is FWD, while type in candidate is concrete 3883d5caef5bSAndrii Nakryiko * STRUCT/UNION. In this case candidate graph comes from single compilation 3884d5caef5bSAndrii Nakryiko * unit, so there is exactly one BTF type for each unique C type. After 3885d5caef5bSAndrii Nakryiko * resolving FWD into STRUCT/UNION, there might be more than one BTF type 3886d5caef5bSAndrii Nakryiko * in canonical graph mapping to single BTF type in candidate graph, but 3887d5caef5bSAndrii Nakryiko * because hypothetical mapping maps from canonical to candidate types, it's 3888d5caef5bSAndrii Nakryiko * alright, and we still maintain the property of having single `canon_id` 3889d5caef5bSAndrii Nakryiko * mapping to single `cand_id` (there could be two different `canon_id` 3890d5caef5bSAndrii Nakryiko * mapped to the same `cand_id`, but it's not contradictory). 3891d5caef5bSAndrii Nakryiko * - Type in canonical graph is concrete STRUCT/UNION, while type in candidate 3892d5caef5bSAndrii Nakryiko * graph is FWD. In this case we are just going to check compatibility of 3893d5caef5bSAndrii Nakryiko * STRUCT/UNION and corresponding FWD, and if they are compatible, we'll 3894d5caef5bSAndrii Nakryiko * assume that whatever STRUCT/UNION FWD resolves to must be equivalent to 3895d5caef5bSAndrii Nakryiko * a concrete STRUCT/UNION from canonical graph. If the rest of type graphs 3896d5caef5bSAndrii Nakryiko * turn out equivalent, we'll re-resolve FWD to concrete STRUCT/UNION from 3897d5caef5bSAndrii Nakryiko * canonical graph. 3898d5caef5bSAndrii Nakryiko */ 3899d5caef5bSAndrii Nakryiko static int btf_dedup_is_equiv(struct btf_dedup *d, __u32 cand_id, 3900d5caef5bSAndrii Nakryiko __u32 canon_id) 3901d5caef5bSAndrii Nakryiko { 3902d5caef5bSAndrii Nakryiko struct btf_type *cand_type; 3903d5caef5bSAndrii Nakryiko struct btf_type *canon_type; 3904d5caef5bSAndrii Nakryiko __u32 hypot_type_id; 3905d5caef5bSAndrii Nakryiko __u16 cand_kind; 3906d5caef5bSAndrii Nakryiko __u16 canon_kind; 3907d5caef5bSAndrii Nakryiko int i, eq; 3908d5caef5bSAndrii Nakryiko 3909d5caef5bSAndrii Nakryiko /* if both resolve to the same canonical, they must be equivalent */ 3910d5caef5bSAndrii Nakryiko if (resolve_type_id(d, cand_id) == resolve_type_id(d, canon_id)) 3911d5caef5bSAndrii Nakryiko return 1; 3912d5caef5bSAndrii Nakryiko 3913d5caef5bSAndrii Nakryiko canon_id = resolve_fwd_id(d, canon_id); 3914d5caef5bSAndrii Nakryiko 3915d5caef5bSAndrii Nakryiko hypot_type_id = d->hypot_map[canon_id]; 39166b6e6b1dSAndrii Nakryiko if (hypot_type_id <= BTF_MAX_NR_TYPES) { 39176b6e6b1dSAndrii Nakryiko /* In some cases compiler will generate different DWARF types 39186b6e6b1dSAndrii Nakryiko * for *identical* array type definitions and use them for 39196b6e6b1dSAndrii Nakryiko * different fields within the *same* struct. This breaks type 39206b6e6b1dSAndrii Nakryiko * equivalence check, which makes an assumption that candidate 39216b6e6b1dSAndrii Nakryiko * types sub-graph has a consistent and deduped-by-compiler 39226b6e6b1dSAndrii Nakryiko * types within a single CU. So work around that by explicitly 39236b6e6b1dSAndrii Nakryiko * allowing identical array types here. 39246b6e6b1dSAndrii Nakryiko */ 39256b6e6b1dSAndrii Nakryiko return hypot_type_id == cand_id || 39266b6e6b1dSAndrii Nakryiko btf_dedup_identical_arrays(d, hypot_type_id, cand_id); 39276b6e6b1dSAndrii Nakryiko } 3928d5caef5bSAndrii Nakryiko 3929d5caef5bSAndrii Nakryiko if (btf_dedup_hypot_map_add(d, canon_id, cand_id)) 3930d5caef5bSAndrii Nakryiko return -ENOMEM; 3931d5caef5bSAndrii Nakryiko 3932740e69c3SAndrii Nakryiko cand_type = btf_type_by_id(d->btf, cand_id); 3933740e69c3SAndrii Nakryiko canon_type = btf_type_by_id(d->btf, canon_id); 3934b03bc685SAndrii Nakryiko cand_kind = btf_kind(cand_type); 3935b03bc685SAndrii Nakryiko canon_kind = btf_kind(canon_type); 3936d5caef5bSAndrii Nakryiko 3937d5caef5bSAndrii Nakryiko if (cand_type->name_off != canon_type->name_off) 3938d5caef5bSAndrii Nakryiko return 0; 3939d5caef5bSAndrii Nakryiko 3940d5caef5bSAndrii Nakryiko /* FWD <--> STRUCT/UNION equivalence check, if enabled */ 3941d5caef5bSAndrii Nakryiko if (!d->opts.dont_resolve_fwds 3942d5caef5bSAndrii Nakryiko && (cand_kind == BTF_KIND_FWD || canon_kind == BTF_KIND_FWD) 3943d5caef5bSAndrii Nakryiko && cand_kind != canon_kind) { 3944d5caef5bSAndrii Nakryiko __u16 real_kind; 3945d5caef5bSAndrii Nakryiko __u16 fwd_kind; 3946d5caef5bSAndrii Nakryiko 3947d5caef5bSAndrii Nakryiko if (cand_kind == BTF_KIND_FWD) { 3948d5caef5bSAndrii Nakryiko real_kind = canon_kind; 3949d5caef5bSAndrii Nakryiko fwd_kind = btf_fwd_kind(cand_type); 3950d5caef5bSAndrii Nakryiko } else { 3951d5caef5bSAndrii Nakryiko real_kind = cand_kind; 3952d5caef5bSAndrii Nakryiko fwd_kind = btf_fwd_kind(canon_type); 3953f86524efSAndrii Nakryiko /* we'd need to resolve base FWD to STRUCT/UNION */ 3954f86524efSAndrii Nakryiko if (fwd_kind == real_kind && canon_id < d->btf->start_id) 3955f86524efSAndrii Nakryiko d->hypot_adjust_canon = true; 3956d5caef5bSAndrii Nakryiko } 3957d5caef5bSAndrii Nakryiko return fwd_kind == real_kind; 3958d5caef5bSAndrii Nakryiko } 3959d5caef5bSAndrii Nakryiko 39609ec71c1cSAndrii Nakryiko if (cand_kind != canon_kind) 39619ec71c1cSAndrii Nakryiko return 0; 39629ec71c1cSAndrii Nakryiko 3963d5caef5bSAndrii Nakryiko switch (cand_kind) { 3964d5caef5bSAndrii Nakryiko case BTF_KIND_INT: 396530025e8bSYonghong Song return btf_equal_int_tag(cand_type, canon_type); 3966d5caef5bSAndrii Nakryiko 3967d5caef5bSAndrii Nakryiko case BTF_KIND_ENUM: 39689768095bSAndrii Nakryiko if (d->opts.dont_resolve_fwds) 3969d5caef5bSAndrii Nakryiko return btf_equal_enum(cand_type, canon_type); 39709768095bSAndrii Nakryiko else 39719768095bSAndrii Nakryiko return btf_compat_enum(cand_type, canon_type); 3972d5caef5bSAndrii Nakryiko 3973d5caef5bSAndrii Nakryiko case BTF_KIND_FWD: 397422541a9eSIlya Leoshkevich case BTF_KIND_FLOAT: 3975d5caef5bSAndrii Nakryiko return btf_equal_common(cand_type, canon_type); 3976d5caef5bSAndrii Nakryiko 3977d5caef5bSAndrii Nakryiko case BTF_KIND_CONST: 3978d5caef5bSAndrii Nakryiko case BTF_KIND_VOLATILE: 3979d5caef5bSAndrii Nakryiko case BTF_KIND_RESTRICT: 3980d5caef5bSAndrii Nakryiko case BTF_KIND_PTR: 3981d5caef5bSAndrii Nakryiko case BTF_KIND_TYPEDEF: 3982d5caef5bSAndrii Nakryiko case BTF_KIND_FUNC: 39839768095bSAndrii Nakryiko if (cand_type->info != canon_type->info) 39849768095bSAndrii Nakryiko return 0; 3985d5caef5bSAndrii Nakryiko return btf_dedup_is_equiv(d, cand_type->type, canon_type->type); 3986d5caef5bSAndrii Nakryiko 3987d5caef5bSAndrii Nakryiko case BTF_KIND_ARRAY: { 3988b03bc685SAndrii Nakryiko const struct btf_array *cand_arr, *canon_arr; 3989d5caef5bSAndrii Nakryiko 3990d5caef5bSAndrii Nakryiko if (!btf_compat_array(cand_type, canon_type)) 3991d5caef5bSAndrii Nakryiko return 0; 3992b03bc685SAndrii Nakryiko cand_arr = btf_array(cand_type); 3993b03bc685SAndrii Nakryiko canon_arr = btf_array(canon_type); 3994f86524efSAndrii Nakryiko eq = btf_dedup_is_equiv(d, cand_arr->index_type, canon_arr->index_type); 3995d5caef5bSAndrii Nakryiko if (eq <= 0) 3996d5caef5bSAndrii Nakryiko return eq; 3997d5caef5bSAndrii Nakryiko return btf_dedup_is_equiv(d, cand_arr->type, canon_arr->type); 3998d5caef5bSAndrii Nakryiko } 3999d5caef5bSAndrii Nakryiko 4000d5caef5bSAndrii Nakryiko case BTF_KIND_STRUCT: 4001d5caef5bSAndrii Nakryiko case BTF_KIND_UNION: { 4002b03bc685SAndrii Nakryiko const struct btf_member *cand_m, *canon_m; 4003d5caef5bSAndrii Nakryiko __u16 vlen; 4004d5caef5bSAndrii Nakryiko 400591097fbeSAndrii Nakryiko if (!btf_shallow_equal_struct(cand_type, canon_type)) 4006d5caef5bSAndrii Nakryiko return 0; 4007b03bc685SAndrii Nakryiko vlen = btf_vlen(cand_type); 4008b03bc685SAndrii Nakryiko cand_m = btf_members(cand_type); 4009b03bc685SAndrii Nakryiko canon_m = btf_members(canon_type); 4010d5caef5bSAndrii Nakryiko for (i = 0; i < vlen; i++) { 4011d5caef5bSAndrii Nakryiko eq = btf_dedup_is_equiv(d, cand_m->type, canon_m->type); 4012d5caef5bSAndrii Nakryiko if (eq <= 0) 4013d5caef5bSAndrii Nakryiko return eq; 4014d5caef5bSAndrii Nakryiko cand_m++; 4015d5caef5bSAndrii Nakryiko canon_m++; 4016d5caef5bSAndrii Nakryiko } 4017d5caef5bSAndrii Nakryiko 4018d5caef5bSAndrii Nakryiko return 1; 4019d5caef5bSAndrii Nakryiko } 4020d5caef5bSAndrii Nakryiko 4021d5caef5bSAndrii Nakryiko case BTF_KIND_FUNC_PROTO: { 4022b03bc685SAndrii Nakryiko const struct btf_param *cand_p, *canon_p; 4023d5caef5bSAndrii Nakryiko __u16 vlen; 4024d5caef5bSAndrii Nakryiko 4025d5caef5bSAndrii Nakryiko if (!btf_compat_fnproto(cand_type, canon_type)) 4026d5caef5bSAndrii Nakryiko return 0; 4027d5caef5bSAndrii Nakryiko eq = btf_dedup_is_equiv(d, cand_type->type, canon_type->type); 4028d5caef5bSAndrii Nakryiko if (eq <= 0) 4029d5caef5bSAndrii Nakryiko return eq; 4030b03bc685SAndrii Nakryiko vlen = btf_vlen(cand_type); 4031b03bc685SAndrii Nakryiko cand_p = btf_params(cand_type); 4032b03bc685SAndrii Nakryiko canon_p = btf_params(canon_type); 4033d5caef5bSAndrii Nakryiko for (i = 0; i < vlen; i++) { 4034d5caef5bSAndrii Nakryiko eq = btf_dedup_is_equiv(d, cand_p->type, canon_p->type); 4035d5caef5bSAndrii Nakryiko if (eq <= 0) 4036d5caef5bSAndrii Nakryiko return eq; 4037d5caef5bSAndrii Nakryiko cand_p++; 4038d5caef5bSAndrii Nakryiko canon_p++; 4039d5caef5bSAndrii Nakryiko } 4040d5caef5bSAndrii Nakryiko return 1; 4041d5caef5bSAndrii Nakryiko } 4042d5caef5bSAndrii Nakryiko 4043d5caef5bSAndrii Nakryiko default: 4044d5caef5bSAndrii Nakryiko return -EINVAL; 4045d5caef5bSAndrii Nakryiko } 4046d5caef5bSAndrii Nakryiko return 0; 4047d5caef5bSAndrii Nakryiko } 4048d5caef5bSAndrii Nakryiko 4049d5caef5bSAndrii Nakryiko /* 4050d5caef5bSAndrii Nakryiko * Use hypothetical mapping, produced by successful type graph equivalence 4051d5caef5bSAndrii Nakryiko * check, to augment existing struct/union canonical mapping, where possible. 4052d5caef5bSAndrii Nakryiko * 4053d5caef5bSAndrii Nakryiko * If BTF_KIND_FWD resolution is allowed, this mapping is also used to record 4054d5caef5bSAndrii Nakryiko * FWD -> STRUCT/UNION correspondence as well. FWD resolution is bidirectional: 4055d5caef5bSAndrii Nakryiko * it doesn't matter if FWD type was part of canonical graph or candidate one, 4056d5caef5bSAndrii Nakryiko * we are recording the mapping anyway. As opposed to carefulness required 4057d5caef5bSAndrii Nakryiko * for struct/union correspondence mapping (described below), for FWD resolution 4058d5caef5bSAndrii Nakryiko * it's not important, as by the time that FWD type (reference type) will be 4059d5caef5bSAndrii Nakryiko * deduplicated all structs/unions will be deduped already anyway. 4060d5caef5bSAndrii Nakryiko * 4061d5caef5bSAndrii Nakryiko * Recording STRUCT/UNION mapping is purely a performance optimization and is 4062d5caef5bSAndrii Nakryiko * not required for correctness. It needs to be done carefully to ensure that 4063d5caef5bSAndrii Nakryiko * struct/union from candidate's type graph is not mapped into corresponding 4064d5caef5bSAndrii Nakryiko * struct/union from canonical type graph that itself hasn't been resolved into 4065d5caef5bSAndrii Nakryiko * canonical representative. The only guarantee we have is that canonical 4066d5caef5bSAndrii Nakryiko * struct/union was determined as canonical and that won't change. But any 4067d5caef5bSAndrii Nakryiko * types referenced through that struct/union fields could have been not yet 4068d5caef5bSAndrii Nakryiko * resolved, so in case like that it's too early to establish any kind of 4069d5caef5bSAndrii Nakryiko * correspondence between structs/unions. 4070d5caef5bSAndrii Nakryiko * 4071d5caef5bSAndrii Nakryiko * No canonical correspondence is derived for primitive types (they are already 4072d5caef5bSAndrii Nakryiko * deduplicated completely already anyway) or reference types (they rely on 4073d5caef5bSAndrii Nakryiko * stability of struct/union canonical relationship for equivalence checks). 4074d5caef5bSAndrii Nakryiko */ 4075d5caef5bSAndrii Nakryiko static void btf_dedup_merge_hypot_map(struct btf_dedup *d) 4076d5caef5bSAndrii Nakryiko { 4077f86524efSAndrii Nakryiko __u32 canon_type_id, targ_type_id; 4078d5caef5bSAndrii Nakryiko __u16 t_kind, c_kind; 4079d5caef5bSAndrii Nakryiko __u32 t_id, c_id; 4080d5caef5bSAndrii Nakryiko int i; 4081d5caef5bSAndrii Nakryiko 4082d5caef5bSAndrii Nakryiko for (i = 0; i < d->hypot_cnt; i++) { 4083f86524efSAndrii Nakryiko canon_type_id = d->hypot_list[i]; 4084f86524efSAndrii Nakryiko targ_type_id = d->hypot_map[canon_type_id]; 4085d5caef5bSAndrii Nakryiko t_id = resolve_type_id(d, targ_type_id); 4086f86524efSAndrii Nakryiko c_id = resolve_type_id(d, canon_type_id); 4087740e69c3SAndrii Nakryiko t_kind = btf_kind(btf__type_by_id(d->btf, t_id)); 4088740e69c3SAndrii Nakryiko c_kind = btf_kind(btf__type_by_id(d->btf, c_id)); 4089d5caef5bSAndrii Nakryiko /* 4090d5caef5bSAndrii Nakryiko * Resolve FWD into STRUCT/UNION. 4091d5caef5bSAndrii Nakryiko * It's ok to resolve FWD into STRUCT/UNION that's not yet 4092d5caef5bSAndrii Nakryiko * mapped to canonical representative (as opposed to 4093d5caef5bSAndrii Nakryiko * STRUCT/UNION <--> STRUCT/UNION mapping logic below), because 4094d5caef5bSAndrii Nakryiko * eventually that struct is going to be mapped and all resolved 4095d5caef5bSAndrii Nakryiko * FWDs will automatically resolve to correct canonical 4096d5caef5bSAndrii Nakryiko * representative. This will happen before ref type deduping, 4097d5caef5bSAndrii Nakryiko * which critically depends on stability of these mapping. This 4098d5caef5bSAndrii Nakryiko * stability is not a requirement for STRUCT/UNION equivalence 4099d5caef5bSAndrii Nakryiko * checks, though. 4100d5caef5bSAndrii Nakryiko */ 4101f86524efSAndrii Nakryiko 4102f86524efSAndrii Nakryiko /* if it's the split BTF case, we still need to point base FWD 4103f86524efSAndrii Nakryiko * to STRUCT/UNION in a split BTF, because FWDs from split BTF 4104f86524efSAndrii Nakryiko * will be resolved against base FWD. If we don't point base 4105f86524efSAndrii Nakryiko * canonical FWD to the resolved STRUCT/UNION, then all the 4106f86524efSAndrii Nakryiko * FWDs in split BTF won't be correctly resolved to a proper 4107f86524efSAndrii Nakryiko * STRUCT/UNION. 4108f86524efSAndrii Nakryiko */ 4109d5caef5bSAndrii Nakryiko if (t_kind != BTF_KIND_FWD && c_kind == BTF_KIND_FWD) 4110d5caef5bSAndrii Nakryiko d->map[c_id] = t_id; 4111f86524efSAndrii Nakryiko 4112f86524efSAndrii Nakryiko /* if graph equivalence determined that we'd need to adjust 4113f86524efSAndrii Nakryiko * base canonical types, then we need to only point base FWDs 4114f86524efSAndrii Nakryiko * to STRUCTs/UNIONs and do no more modifications. For all 4115f86524efSAndrii Nakryiko * other purposes the type graphs were not equivalent. 4116f86524efSAndrii Nakryiko */ 4117f86524efSAndrii Nakryiko if (d->hypot_adjust_canon) 4118f86524efSAndrii Nakryiko continue; 4119f86524efSAndrii Nakryiko 4120f86524efSAndrii Nakryiko if (t_kind == BTF_KIND_FWD && c_kind != BTF_KIND_FWD) 4121d5caef5bSAndrii Nakryiko d->map[t_id] = c_id; 4122d5caef5bSAndrii Nakryiko 4123d5caef5bSAndrii Nakryiko if ((t_kind == BTF_KIND_STRUCT || t_kind == BTF_KIND_UNION) && 4124d5caef5bSAndrii Nakryiko c_kind != BTF_KIND_FWD && 4125d5caef5bSAndrii Nakryiko is_type_mapped(d, c_id) && 4126d5caef5bSAndrii Nakryiko !is_type_mapped(d, t_id)) { 4127d5caef5bSAndrii Nakryiko /* 4128d5caef5bSAndrii Nakryiko * as a perf optimization, we can map struct/union 4129d5caef5bSAndrii Nakryiko * that's part of type graph we just verified for 4130d5caef5bSAndrii Nakryiko * equivalence. We can do that for struct/union that has 4131d5caef5bSAndrii Nakryiko * canonical representative only, though. 4132d5caef5bSAndrii Nakryiko */ 4133d5caef5bSAndrii Nakryiko d->map[t_id] = c_id; 4134d5caef5bSAndrii Nakryiko } 4135d5caef5bSAndrii Nakryiko } 4136d5caef5bSAndrii Nakryiko } 4137d5caef5bSAndrii Nakryiko 4138d5caef5bSAndrii Nakryiko /* 4139d5caef5bSAndrii Nakryiko * Deduplicate struct/union types. 4140d5caef5bSAndrii Nakryiko * 4141d5caef5bSAndrii Nakryiko * For each struct/union type its type signature hash is calculated, taking 4142d5caef5bSAndrii Nakryiko * into account type's name, size, number, order and names of fields, but 4143d5caef5bSAndrii Nakryiko * ignoring type ID's referenced from fields, because they might not be deduped 4144d5caef5bSAndrii Nakryiko * completely until after reference types deduplication phase. This type hash 4145d5caef5bSAndrii Nakryiko * is used to iterate over all potential canonical types, sharing same hash. 4146d5caef5bSAndrii Nakryiko * For each canonical candidate we check whether type graphs that they form 4147d5caef5bSAndrii Nakryiko * (through referenced types in fields and so on) are equivalent using algorithm 4148d5caef5bSAndrii Nakryiko * implemented in `btf_dedup_is_equiv`. If such equivalence is found and 4149d5caef5bSAndrii Nakryiko * BTF_KIND_FWD resolution is allowed, then hypothetical mapping 4150d5caef5bSAndrii Nakryiko * (btf_dedup->hypot_map) produced by aforementioned type graph equivalence 4151d5caef5bSAndrii Nakryiko * algorithm is used to record FWD -> STRUCT/UNION mapping. It's also used to 4152d5caef5bSAndrii Nakryiko * potentially map other structs/unions to their canonical representatives, 4153d5caef5bSAndrii Nakryiko * if such relationship hasn't yet been established. This speeds up algorithm 4154d5caef5bSAndrii Nakryiko * by eliminating some of the duplicate work. 4155d5caef5bSAndrii Nakryiko * 4156d5caef5bSAndrii Nakryiko * If no matching canonical representative was found, struct/union is marked 4157d5caef5bSAndrii Nakryiko * as canonical for itself and is added into btf_dedup->dedup_table hash map 4158d5caef5bSAndrii Nakryiko * for further look ups. 4159d5caef5bSAndrii Nakryiko */ 4160d5caef5bSAndrii Nakryiko static int btf_dedup_struct_type(struct btf_dedup *d, __u32 type_id) 4161d5caef5bSAndrii Nakryiko { 416291097fbeSAndrii Nakryiko struct btf_type *cand_type, *t; 41632fc3fc0bSAndrii Nakryiko struct hashmap_entry *hash_entry; 4164d5caef5bSAndrii Nakryiko /* if we don't find equivalent type, then we are canonical */ 4165d5caef5bSAndrii Nakryiko __u32 new_id = type_id; 4166d5caef5bSAndrii Nakryiko __u16 kind; 41672fc3fc0bSAndrii Nakryiko long h; 4168d5caef5bSAndrii Nakryiko 4169d5caef5bSAndrii Nakryiko /* already deduped or is in process of deduping (loop detected) */ 41705aab392cSAndrii Nakryiko if (d->map[type_id] <= BTF_MAX_NR_TYPES) 4171d5caef5bSAndrii Nakryiko return 0; 4172d5caef5bSAndrii Nakryiko 4173740e69c3SAndrii Nakryiko t = btf_type_by_id(d->btf, type_id); 4174b03bc685SAndrii Nakryiko kind = btf_kind(t); 4175d5caef5bSAndrii Nakryiko 4176d5caef5bSAndrii Nakryiko if (kind != BTF_KIND_STRUCT && kind != BTF_KIND_UNION) 4177d5caef5bSAndrii Nakryiko return 0; 4178d5caef5bSAndrii Nakryiko 4179d5caef5bSAndrii Nakryiko h = btf_hash_struct(t); 41802fc3fc0bSAndrii Nakryiko for_each_dedup_cand(d, hash_entry, h) { 41812fc3fc0bSAndrii Nakryiko __u32 cand_id = (__u32)(long)hash_entry->value; 4182d5caef5bSAndrii Nakryiko int eq; 4183d5caef5bSAndrii Nakryiko 418491097fbeSAndrii Nakryiko /* 418591097fbeSAndrii Nakryiko * Even though btf_dedup_is_equiv() checks for 418691097fbeSAndrii Nakryiko * btf_shallow_equal_struct() internally when checking two 418791097fbeSAndrii Nakryiko * structs (unions) for equivalence, we need to guard here 418891097fbeSAndrii Nakryiko * from picking matching FWD type as a dedup candidate. 418991097fbeSAndrii Nakryiko * This can happen due to hash collision. In such case just 419091097fbeSAndrii Nakryiko * relying on btf_dedup_is_equiv() would lead to potentially 419191097fbeSAndrii Nakryiko * creating a loop (FWD -> STRUCT and STRUCT -> FWD), because 419291097fbeSAndrii Nakryiko * FWD and compatible STRUCT/UNION are considered equivalent. 419391097fbeSAndrii Nakryiko */ 4194740e69c3SAndrii Nakryiko cand_type = btf_type_by_id(d->btf, cand_id); 419591097fbeSAndrii Nakryiko if (!btf_shallow_equal_struct(t, cand_type)) 419691097fbeSAndrii Nakryiko continue; 419791097fbeSAndrii Nakryiko 4198d5caef5bSAndrii Nakryiko btf_dedup_clear_hypot_map(d); 41992fc3fc0bSAndrii Nakryiko eq = btf_dedup_is_equiv(d, type_id, cand_id); 4200d5caef5bSAndrii Nakryiko if (eq < 0) 4201d5caef5bSAndrii Nakryiko return eq; 4202d5caef5bSAndrii Nakryiko if (!eq) 4203d5caef5bSAndrii Nakryiko continue; 4204d5caef5bSAndrii Nakryiko btf_dedup_merge_hypot_map(d); 4205f86524efSAndrii Nakryiko if (d->hypot_adjust_canon) /* not really equivalent */ 4206f86524efSAndrii Nakryiko continue; 4207f86524efSAndrii Nakryiko new_id = cand_id; 4208d5caef5bSAndrii Nakryiko break; 4209d5caef5bSAndrii Nakryiko } 4210d5caef5bSAndrii Nakryiko 4211d5caef5bSAndrii Nakryiko d->map[type_id] = new_id; 4212d5caef5bSAndrii Nakryiko if (type_id == new_id && btf_dedup_table_add(d, h, type_id)) 4213d5caef5bSAndrii Nakryiko return -ENOMEM; 4214d5caef5bSAndrii Nakryiko 4215d5caef5bSAndrii Nakryiko return 0; 4216d5caef5bSAndrii Nakryiko } 4217d5caef5bSAndrii Nakryiko 4218d5caef5bSAndrii Nakryiko static int btf_dedup_struct_types(struct btf_dedup *d) 4219d5caef5bSAndrii Nakryiko { 4220d5caef5bSAndrii Nakryiko int i, err; 4221d5caef5bSAndrii Nakryiko 4222f86524efSAndrii Nakryiko for (i = 0; i < d->btf->nr_types; i++) { 4223f86524efSAndrii Nakryiko err = btf_dedup_struct_type(d, d->btf->start_id + i); 4224d5caef5bSAndrii Nakryiko if (err) 4225d5caef5bSAndrii Nakryiko return err; 4226d5caef5bSAndrii Nakryiko } 4227d5caef5bSAndrii Nakryiko return 0; 4228d5caef5bSAndrii Nakryiko } 4229d5caef5bSAndrii Nakryiko 4230d5caef5bSAndrii Nakryiko /* 4231d5caef5bSAndrii Nakryiko * Deduplicate reference type. 4232d5caef5bSAndrii Nakryiko * 4233d5caef5bSAndrii Nakryiko * Once all primitive and struct/union types got deduplicated, we can easily 4234d5caef5bSAndrii Nakryiko * deduplicate all other (reference) BTF types. This is done in two steps: 4235d5caef5bSAndrii Nakryiko * 4236d5caef5bSAndrii Nakryiko * 1. Resolve all referenced type IDs into their canonical type IDs. This 4237d5caef5bSAndrii Nakryiko * resolution can be done either immediately for primitive or struct/union types 4238d5caef5bSAndrii Nakryiko * (because they were deduped in previous two phases) or recursively for 4239d5caef5bSAndrii Nakryiko * reference types. Recursion will always terminate at either primitive or 4240d5caef5bSAndrii Nakryiko * struct/union type, at which point we can "unwind" chain of reference types 4241d5caef5bSAndrii Nakryiko * one by one. There is no danger of encountering cycles because in C type 4242d5caef5bSAndrii Nakryiko * system the only way to form type cycle is through struct/union, so any chain 4243d5caef5bSAndrii Nakryiko * of reference types, even those taking part in a type cycle, will inevitably 4244d5caef5bSAndrii Nakryiko * reach struct/union at some point. 4245d5caef5bSAndrii Nakryiko * 4246d5caef5bSAndrii Nakryiko * 2. Once all referenced type IDs are resolved into canonical ones, BTF type 4247d5caef5bSAndrii Nakryiko * becomes "stable", in the sense that no further deduplication will cause 4248d5caef5bSAndrii Nakryiko * any changes to it. With that, it's now possible to calculate type's signature 4249d5caef5bSAndrii Nakryiko * hash (this time taking into account referenced type IDs) and loop over all 4250d5caef5bSAndrii Nakryiko * potential canonical representatives. If no match was found, current type 4251d5caef5bSAndrii Nakryiko * will become canonical representative of itself and will be added into 4252d5caef5bSAndrii Nakryiko * btf_dedup->dedup_table as another possible canonical representative. 4253d5caef5bSAndrii Nakryiko */ 4254d5caef5bSAndrii Nakryiko static int btf_dedup_ref_type(struct btf_dedup *d, __u32 type_id) 4255d5caef5bSAndrii Nakryiko { 42562fc3fc0bSAndrii Nakryiko struct hashmap_entry *hash_entry; 42572fc3fc0bSAndrii Nakryiko __u32 new_id = type_id, cand_id; 4258d5caef5bSAndrii Nakryiko struct btf_type *t, *cand; 4259d5caef5bSAndrii Nakryiko /* if we don't find equivalent type, then we are representative type */ 42603d8669e6SDan Carpenter int ref_type_id; 42612fc3fc0bSAndrii Nakryiko long h; 4262d5caef5bSAndrii Nakryiko 4263d5caef5bSAndrii Nakryiko if (d->map[type_id] == BTF_IN_PROGRESS_ID) 4264d5caef5bSAndrii Nakryiko return -ELOOP; 42655aab392cSAndrii Nakryiko if (d->map[type_id] <= BTF_MAX_NR_TYPES) 4266d5caef5bSAndrii Nakryiko return resolve_type_id(d, type_id); 4267d5caef5bSAndrii Nakryiko 4268740e69c3SAndrii Nakryiko t = btf_type_by_id(d->btf, type_id); 4269d5caef5bSAndrii Nakryiko d->map[type_id] = BTF_IN_PROGRESS_ID; 4270d5caef5bSAndrii Nakryiko 4271b03bc685SAndrii Nakryiko switch (btf_kind(t)) { 4272d5caef5bSAndrii Nakryiko case BTF_KIND_CONST: 4273d5caef5bSAndrii Nakryiko case BTF_KIND_VOLATILE: 4274d5caef5bSAndrii Nakryiko case BTF_KIND_RESTRICT: 4275d5caef5bSAndrii Nakryiko case BTF_KIND_PTR: 4276d5caef5bSAndrii Nakryiko case BTF_KIND_TYPEDEF: 4277d5caef5bSAndrii Nakryiko case BTF_KIND_FUNC: 4278d5caef5bSAndrii Nakryiko ref_type_id = btf_dedup_ref_type(d, t->type); 4279d5caef5bSAndrii Nakryiko if (ref_type_id < 0) 4280d5caef5bSAndrii Nakryiko return ref_type_id; 4281d5caef5bSAndrii Nakryiko t->type = ref_type_id; 4282d5caef5bSAndrii Nakryiko 4283d5caef5bSAndrii Nakryiko h = btf_hash_common(t); 42842fc3fc0bSAndrii Nakryiko for_each_dedup_cand(d, hash_entry, h) { 42852fc3fc0bSAndrii Nakryiko cand_id = (__u32)(long)hash_entry->value; 4286740e69c3SAndrii Nakryiko cand = btf_type_by_id(d->btf, cand_id); 4287d5caef5bSAndrii Nakryiko if (btf_equal_common(t, cand)) { 42882fc3fc0bSAndrii Nakryiko new_id = cand_id; 4289d5caef5bSAndrii Nakryiko break; 4290d5caef5bSAndrii Nakryiko } 4291d5caef5bSAndrii Nakryiko } 4292d5caef5bSAndrii Nakryiko break; 4293d5caef5bSAndrii Nakryiko 4294223f903eSYonghong Song case BTF_KIND_DECL_TAG: 42955b84bd10SYonghong Song ref_type_id = btf_dedup_ref_type(d, t->type); 42965b84bd10SYonghong Song if (ref_type_id < 0) 42975b84bd10SYonghong Song return ref_type_id; 42985b84bd10SYonghong Song t->type = ref_type_id; 42995b84bd10SYonghong Song 4300223f903eSYonghong Song h = btf_hash_int_decl_tag(t); 43015b84bd10SYonghong Song for_each_dedup_cand(d, hash_entry, h) { 43025b84bd10SYonghong Song cand_id = (__u32)(long)hash_entry->value; 43035b84bd10SYonghong Song cand = btf_type_by_id(d->btf, cand_id); 43045b84bd10SYonghong Song if (btf_equal_int_tag(t, cand)) { 43055b84bd10SYonghong Song new_id = cand_id; 43065b84bd10SYonghong Song break; 43075b84bd10SYonghong Song } 43085b84bd10SYonghong Song } 43095b84bd10SYonghong Song break; 43105b84bd10SYonghong Song 4311d5caef5bSAndrii Nakryiko case BTF_KIND_ARRAY: { 4312b03bc685SAndrii Nakryiko struct btf_array *info = btf_array(t); 4313d5caef5bSAndrii Nakryiko 4314d5caef5bSAndrii Nakryiko ref_type_id = btf_dedup_ref_type(d, info->type); 4315d5caef5bSAndrii Nakryiko if (ref_type_id < 0) 4316d5caef5bSAndrii Nakryiko return ref_type_id; 4317d5caef5bSAndrii Nakryiko info->type = ref_type_id; 4318d5caef5bSAndrii Nakryiko 4319d5caef5bSAndrii Nakryiko ref_type_id = btf_dedup_ref_type(d, info->index_type); 4320d5caef5bSAndrii Nakryiko if (ref_type_id < 0) 4321d5caef5bSAndrii Nakryiko return ref_type_id; 4322d5caef5bSAndrii Nakryiko info->index_type = ref_type_id; 4323d5caef5bSAndrii Nakryiko 4324d5caef5bSAndrii Nakryiko h = btf_hash_array(t); 43252fc3fc0bSAndrii Nakryiko for_each_dedup_cand(d, hash_entry, h) { 43262fc3fc0bSAndrii Nakryiko cand_id = (__u32)(long)hash_entry->value; 4327740e69c3SAndrii Nakryiko cand = btf_type_by_id(d->btf, cand_id); 4328d5caef5bSAndrii Nakryiko if (btf_equal_array(t, cand)) { 43292fc3fc0bSAndrii Nakryiko new_id = cand_id; 4330d5caef5bSAndrii Nakryiko break; 4331d5caef5bSAndrii Nakryiko } 4332d5caef5bSAndrii Nakryiko } 4333d5caef5bSAndrii Nakryiko break; 4334d5caef5bSAndrii Nakryiko } 4335d5caef5bSAndrii Nakryiko 4336d5caef5bSAndrii Nakryiko case BTF_KIND_FUNC_PROTO: { 4337d5caef5bSAndrii Nakryiko struct btf_param *param; 4338d5caef5bSAndrii Nakryiko __u16 vlen; 4339d5caef5bSAndrii Nakryiko int i; 4340d5caef5bSAndrii Nakryiko 4341d5caef5bSAndrii Nakryiko ref_type_id = btf_dedup_ref_type(d, t->type); 4342d5caef5bSAndrii Nakryiko if (ref_type_id < 0) 4343d5caef5bSAndrii Nakryiko return ref_type_id; 4344d5caef5bSAndrii Nakryiko t->type = ref_type_id; 4345d5caef5bSAndrii Nakryiko 4346b03bc685SAndrii Nakryiko vlen = btf_vlen(t); 4347b03bc685SAndrii Nakryiko param = btf_params(t); 4348d5caef5bSAndrii Nakryiko for (i = 0; i < vlen; i++) { 4349d5caef5bSAndrii Nakryiko ref_type_id = btf_dedup_ref_type(d, param->type); 4350d5caef5bSAndrii Nakryiko if (ref_type_id < 0) 4351d5caef5bSAndrii Nakryiko return ref_type_id; 4352d5caef5bSAndrii Nakryiko param->type = ref_type_id; 4353d5caef5bSAndrii Nakryiko param++; 4354d5caef5bSAndrii Nakryiko } 4355d5caef5bSAndrii Nakryiko 4356d5caef5bSAndrii Nakryiko h = btf_hash_fnproto(t); 43572fc3fc0bSAndrii Nakryiko for_each_dedup_cand(d, hash_entry, h) { 43582fc3fc0bSAndrii Nakryiko cand_id = (__u32)(long)hash_entry->value; 4359740e69c3SAndrii Nakryiko cand = btf_type_by_id(d->btf, cand_id); 4360d5caef5bSAndrii Nakryiko if (btf_equal_fnproto(t, cand)) { 43612fc3fc0bSAndrii Nakryiko new_id = cand_id; 4362d5caef5bSAndrii Nakryiko break; 4363d5caef5bSAndrii Nakryiko } 4364d5caef5bSAndrii Nakryiko } 4365d5caef5bSAndrii Nakryiko break; 4366d5caef5bSAndrii Nakryiko } 4367d5caef5bSAndrii Nakryiko 4368d5caef5bSAndrii Nakryiko default: 4369d5caef5bSAndrii Nakryiko return -EINVAL; 4370d5caef5bSAndrii Nakryiko } 4371d5caef5bSAndrii Nakryiko 4372d5caef5bSAndrii Nakryiko d->map[type_id] = new_id; 4373d5caef5bSAndrii Nakryiko if (type_id == new_id && btf_dedup_table_add(d, h, type_id)) 4374d5caef5bSAndrii Nakryiko return -ENOMEM; 4375d5caef5bSAndrii Nakryiko 4376d5caef5bSAndrii Nakryiko return new_id; 4377d5caef5bSAndrii Nakryiko } 4378d5caef5bSAndrii Nakryiko 4379d5caef5bSAndrii Nakryiko static int btf_dedup_ref_types(struct btf_dedup *d) 4380d5caef5bSAndrii Nakryiko { 4381d5caef5bSAndrii Nakryiko int i, err; 4382d5caef5bSAndrii Nakryiko 4383f86524efSAndrii Nakryiko for (i = 0; i < d->btf->nr_types; i++) { 4384f86524efSAndrii Nakryiko err = btf_dedup_ref_type(d, d->btf->start_id + i); 4385d5caef5bSAndrii Nakryiko if (err < 0) 4386d5caef5bSAndrii Nakryiko return err; 4387d5caef5bSAndrii Nakryiko } 43882fc3fc0bSAndrii Nakryiko /* we won't need d->dedup_table anymore */ 43892fc3fc0bSAndrii Nakryiko hashmap__free(d->dedup_table); 43902fc3fc0bSAndrii Nakryiko d->dedup_table = NULL; 4391d5caef5bSAndrii Nakryiko return 0; 4392d5caef5bSAndrii Nakryiko } 4393d5caef5bSAndrii Nakryiko 4394d5caef5bSAndrii Nakryiko /* 4395d5caef5bSAndrii Nakryiko * Compact types. 4396d5caef5bSAndrii Nakryiko * 4397d5caef5bSAndrii Nakryiko * After we established for each type its corresponding canonical representative 4398d5caef5bSAndrii Nakryiko * type, we now can eliminate types that are not canonical and leave only 4399d5caef5bSAndrii Nakryiko * canonical ones layed out sequentially in memory by copying them over 4400d5caef5bSAndrii Nakryiko * duplicates. During compaction btf_dedup->hypot_map array is reused to store 4401d5caef5bSAndrii Nakryiko * a map from original type ID to a new compacted type ID, which will be used 4402d5caef5bSAndrii Nakryiko * during next phase to "fix up" type IDs, referenced from struct/union and 4403d5caef5bSAndrii Nakryiko * reference types. 4404d5caef5bSAndrii Nakryiko */ 4405d5caef5bSAndrii Nakryiko static int btf_dedup_compact_types(struct btf_dedup *d) 4406d5caef5bSAndrii Nakryiko { 4407740e69c3SAndrii Nakryiko __u32 *new_offs; 4408f86524efSAndrii Nakryiko __u32 next_type_id = d->btf->start_id; 4409f86524efSAndrii Nakryiko const struct btf_type *t; 4410740e69c3SAndrii Nakryiko void *p; 4411f86524efSAndrii Nakryiko int i, id, len; 4412d5caef5bSAndrii Nakryiko 4413d5caef5bSAndrii Nakryiko /* we are going to reuse hypot_map to store compaction remapping */ 4414d5caef5bSAndrii Nakryiko d->hypot_map[0] = 0; 4415f86524efSAndrii Nakryiko /* base BTF types are not renumbered */ 4416f86524efSAndrii Nakryiko for (id = 1; id < d->btf->start_id; id++) 4417f86524efSAndrii Nakryiko d->hypot_map[id] = id; 4418f86524efSAndrii Nakryiko for (i = 0, id = d->btf->start_id; i < d->btf->nr_types; i++, id++) 4419f86524efSAndrii Nakryiko d->hypot_map[id] = BTF_UNPROCESSED_ID; 4420d5caef5bSAndrii Nakryiko 4421740e69c3SAndrii Nakryiko p = d->btf->types_data; 4422d5caef5bSAndrii Nakryiko 4423f86524efSAndrii Nakryiko for (i = 0, id = d->btf->start_id; i < d->btf->nr_types; i++, id++) { 4424f86524efSAndrii Nakryiko if (d->map[id] != id) 4425d5caef5bSAndrii Nakryiko continue; 4426d5caef5bSAndrii Nakryiko 4427f86524efSAndrii Nakryiko t = btf__type_by_id(d->btf, id); 4428f86524efSAndrii Nakryiko len = btf_type_size(t); 4429d5caef5bSAndrii Nakryiko if (len < 0) 4430d5caef5bSAndrii Nakryiko return len; 4431d5caef5bSAndrii Nakryiko 4432f86524efSAndrii Nakryiko memmove(p, t, len); 4433f86524efSAndrii Nakryiko d->hypot_map[id] = next_type_id; 4434f86524efSAndrii Nakryiko d->btf->type_offs[next_type_id - d->btf->start_id] = p - d->btf->types_data; 4435d5caef5bSAndrii Nakryiko p += len; 4436d5caef5bSAndrii Nakryiko next_type_id++; 4437d5caef5bSAndrii Nakryiko } 4438d5caef5bSAndrii Nakryiko 4439d5caef5bSAndrii Nakryiko /* shrink struct btf's internal types index and update btf_header */ 4440f86524efSAndrii Nakryiko d->btf->nr_types = next_type_id - d->btf->start_id; 4441ba451366SAndrii Nakryiko d->btf->type_offs_cap = d->btf->nr_types; 4442740e69c3SAndrii Nakryiko d->btf->hdr->type_len = p - d->btf->types_data; 4443740e69c3SAndrii Nakryiko new_offs = libbpf_reallocarray(d->btf->type_offs, d->btf->type_offs_cap, 4444740e69c3SAndrii Nakryiko sizeof(*new_offs)); 4445f86524efSAndrii Nakryiko if (d->btf->type_offs_cap && !new_offs) 4446d5caef5bSAndrii Nakryiko return -ENOMEM; 4447740e69c3SAndrii Nakryiko d->btf->type_offs = new_offs; 4448919d2b1dSAndrii Nakryiko d->btf->hdr->str_off = d->btf->hdr->type_len; 4449b8604247SAndrii Nakryiko d->btf->raw_size = d->btf->hdr->hdr_len + d->btf->hdr->type_len + d->btf->hdr->str_len; 4450d5caef5bSAndrii Nakryiko return 0; 4451d5caef5bSAndrii Nakryiko } 4452d5caef5bSAndrii Nakryiko 4453d5caef5bSAndrii Nakryiko /* 4454d5caef5bSAndrii Nakryiko * Figure out final (deduplicated and compacted) type ID for provided original 4455d5caef5bSAndrii Nakryiko * `type_id` by first resolving it into corresponding canonical type ID and 4456d5caef5bSAndrii Nakryiko * then mapping it to a deduplicated type ID, stored in btf_dedup->hypot_map, 4457d5caef5bSAndrii Nakryiko * which is populated during compaction phase. 4458d5caef5bSAndrii Nakryiko */ 4459f36e99a4SAndrii Nakryiko static int btf_dedup_remap_type_id(__u32 *type_id, void *ctx) 4460d5caef5bSAndrii Nakryiko { 4461f36e99a4SAndrii Nakryiko struct btf_dedup *d = ctx; 4462d5caef5bSAndrii Nakryiko __u32 resolved_type_id, new_type_id; 4463d5caef5bSAndrii Nakryiko 4464f36e99a4SAndrii Nakryiko resolved_type_id = resolve_type_id(d, *type_id); 4465d5caef5bSAndrii Nakryiko new_type_id = d->hypot_map[resolved_type_id]; 44665aab392cSAndrii Nakryiko if (new_type_id > BTF_MAX_NR_TYPES) 4467d5caef5bSAndrii Nakryiko return -EINVAL; 4468f36e99a4SAndrii Nakryiko 4469f36e99a4SAndrii Nakryiko *type_id = new_type_id; 4470f36e99a4SAndrii Nakryiko return 0; 4471d5caef5bSAndrii Nakryiko } 4472d5caef5bSAndrii Nakryiko 4473d5caef5bSAndrii Nakryiko /* 4474d5caef5bSAndrii Nakryiko * Remap referenced type IDs into deduped type IDs. 4475d5caef5bSAndrii Nakryiko * 4476d5caef5bSAndrii Nakryiko * After BTF types are deduplicated and compacted, their final type IDs may 4477d5caef5bSAndrii Nakryiko * differ from original ones. The map from original to a corresponding 4478d5caef5bSAndrii Nakryiko * deduped type ID is stored in btf_dedup->hypot_map and is populated during 4479d5caef5bSAndrii Nakryiko * compaction phase. During remapping phase we are rewriting all type IDs 4480d5caef5bSAndrii Nakryiko * referenced from any BTF type (e.g., struct fields, func proto args, etc) to 4481d5caef5bSAndrii Nakryiko * their final deduped type IDs. 4482d5caef5bSAndrii Nakryiko */ 4483d5caef5bSAndrii Nakryiko static int btf_dedup_remap_types(struct btf_dedup *d) 4484d5caef5bSAndrii Nakryiko { 4485d5caef5bSAndrii Nakryiko int i, r; 4486d5caef5bSAndrii Nakryiko 4487f86524efSAndrii Nakryiko for (i = 0; i < d->btf->nr_types; i++) { 4488f36e99a4SAndrii Nakryiko struct btf_type *t = btf_type_by_id(d->btf, d->btf->start_id + i); 4489f36e99a4SAndrii Nakryiko 4490f36e99a4SAndrii Nakryiko r = btf_type_visit_type_ids(t, btf_dedup_remap_type_id, d); 4491f36e99a4SAndrii Nakryiko if (r) 4492d5caef5bSAndrii Nakryiko return r; 4493d5caef5bSAndrii Nakryiko } 4494f36e99a4SAndrii Nakryiko 4495f36e99a4SAndrii Nakryiko if (!d->btf_ext) 4496f36e99a4SAndrii Nakryiko return 0; 4497f36e99a4SAndrii Nakryiko 4498f36e99a4SAndrii Nakryiko r = btf_ext_visit_type_ids(d->btf_ext, btf_dedup_remap_type_id, d); 4499f36e99a4SAndrii Nakryiko if (r) 4500f36e99a4SAndrii Nakryiko return r; 4501f36e99a4SAndrii Nakryiko 4502d5caef5bSAndrii Nakryiko return 0; 4503d5caef5bSAndrii Nakryiko } 4504fb2426adSMartin KaFai Lau 4505fb2426adSMartin KaFai Lau /* 4506fb2426adSMartin KaFai Lau * Probe few well-known locations for vmlinux kernel image and try to load BTF 4507fb2426adSMartin KaFai Lau * data out of it to use for target BTF. 4508fb2426adSMartin KaFai Lau */ 4509a710eed3SHengqi Chen struct btf *btf__load_vmlinux_btf(void) 4510fb2426adSMartin KaFai Lau { 4511fb2426adSMartin KaFai Lau struct { 4512fb2426adSMartin KaFai Lau const char *path_fmt; 4513fb2426adSMartin KaFai Lau bool raw_btf; 4514fb2426adSMartin KaFai Lau } locations[] = { 4515fb2426adSMartin KaFai Lau /* try canonical vmlinux BTF through sysfs first */ 4516fb2426adSMartin KaFai Lau { "/sys/kernel/btf/vmlinux", true /* raw BTF */ }, 4517fb2426adSMartin KaFai Lau /* fall back to trying to find vmlinux ELF on disk otherwise */ 4518fb2426adSMartin KaFai Lau { "/boot/vmlinux-%1$s" }, 4519fb2426adSMartin KaFai Lau { "/lib/modules/%1$s/vmlinux-%1$s" }, 4520fb2426adSMartin KaFai Lau { "/lib/modules/%1$s/build/vmlinux" }, 4521fb2426adSMartin KaFai Lau { "/usr/lib/modules/%1$s/kernel/vmlinux" }, 4522fb2426adSMartin KaFai Lau { "/usr/lib/debug/boot/vmlinux-%1$s" }, 4523fb2426adSMartin KaFai Lau { "/usr/lib/debug/boot/vmlinux-%1$s.debug" }, 4524fb2426adSMartin KaFai Lau { "/usr/lib/debug/lib/modules/%1$s/vmlinux" }, 4525fb2426adSMartin KaFai Lau }; 4526fb2426adSMartin KaFai Lau char path[PATH_MAX + 1]; 4527fb2426adSMartin KaFai Lau struct utsname buf; 4528fb2426adSMartin KaFai Lau struct btf *btf; 4529e9fc3ce9SAndrii Nakryiko int i, err; 4530fb2426adSMartin KaFai Lau 4531fb2426adSMartin KaFai Lau uname(&buf); 4532fb2426adSMartin KaFai Lau 4533fb2426adSMartin KaFai Lau for (i = 0; i < ARRAY_SIZE(locations); i++) { 4534fb2426adSMartin KaFai Lau snprintf(path, PATH_MAX, locations[i].path_fmt, buf.release); 4535fb2426adSMartin KaFai Lau 4536fb2426adSMartin KaFai Lau if (access(path, R_OK)) 4537fb2426adSMartin KaFai Lau continue; 4538fb2426adSMartin KaFai Lau 4539fb2426adSMartin KaFai Lau if (locations[i].raw_btf) 454094a1feddSAndrii Nakryiko btf = btf__parse_raw(path); 4541fb2426adSMartin KaFai Lau else 4542fb2426adSMartin KaFai Lau btf = btf__parse_elf(path, NULL); 4543e9fc3ce9SAndrii Nakryiko err = libbpf_get_error(btf); 4544e9fc3ce9SAndrii Nakryiko pr_debug("loading kernel BTF '%s': %d\n", path, err); 4545e9fc3ce9SAndrii Nakryiko if (err) 4546fb2426adSMartin KaFai Lau continue; 4547fb2426adSMartin KaFai Lau 4548fb2426adSMartin KaFai Lau return btf; 4549fb2426adSMartin KaFai Lau } 4550fb2426adSMartin KaFai Lau 4551fb2426adSMartin KaFai Lau pr_warn("failed to find valid kernel BTF\n"); 4552e9fc3ce9SAndrii Nakryiko return libbpf_err_ptr(-ESRCH); 4553fb2426adSMartin KaFai Lau } 4554f36e99a4SAndrii Nakryiko 4555a710eed3SHengqi Chen struct btf *libbpf_find_kernel_btf(void) __attribute__((alias("btf__load_vmlinux_btf"))); 4556a710eed3SHengqi Chen 4557a710eed3SHengqi Chen struct btf *btf__load_module_btf(const char *module_name, struct btf *vmlinux_btf) 4558a710eed3SHengqi Chen { 4559a710eed3SHengqi Chen char path[80]; 4560a710eed3SHengqi Chen 4561a710eed3SHengqi Chen snprintf(path, sizeof(path), "/sys/kernel/btf/%s", module_name); 4562a710eed3SHengqi Chen return btf__parse_split(path, vmlinux_btf); 4563a710eed3SHengqi Chen } 4564a710eed3SHengqi Chen 4565f36e99a4SAndrii Nakryiko int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ctx) 4566f36e99a4SAndrii Nakryiko { 4567f36e99a4SAndrii Nakryiko int i, n, err; 4568f36e99a4SAndrii Nakryiko 4569f36e99a4SAndrii Nakryiko switch (btf_kind(t)) { 4570f36e99a4SAndrii Nakryiko case BTF_KIND_INT: 4571f36e99a4SAndrii Nakryiko case BTF_KIND_FLOAT: 4572f36e99a4SAndrii Nakryiko case BTF_KIND_ENUM: 4573f36e99a4SAndrii Nakryiko return 0; 4574f36e99a4SAndrii Nakryiko 4575f36e99a4SAndrii Nakryiko case BTF_KIND_FWD: 4576f36e99a4SAndrii Nakryiko case BTF_KIND_CONST: 4577f36e99a4SAndrii Nakryiko case BTF_KIND_VOLATILE: 4578f36e99a4SAndrii Nakryiko case BTF_KIND_RESTRICT: 4579f36e99a4SAndrii Nakryiko case BTF_KIND_PTR: 4580f36e99a4SAndrii Nakryiko case BTF_KIND_TYPEDEF: 4581f36e99a4SAndrii Nakryiko case BTF_KIND_FUNC: 4582f36e99a4SAndrii Nakryiko case BTF_KIND_VAR: 4583223f903eSYonghong Song case BTF_KIND_DECL_TAG: 4584f36e99a4SAndrii Nakryiko return visit(&t->type, ctx); 4585f36e99a4SAndrii Nakryiko 4586f36e99a4SAndrii Nakryiko case BTF_KIND_ARRAY: { 4587f36e99a4SAndrii Nakryiko struct btf_array *a = btf_array(t); 4588f36e99a4SAndrii Nakryiko 4589f36e99a4SAndrii Nakryiko err = visit(&a->type, ctx); 4590f36e99a4SAndrii Nakryiko err = err ?: visit(&a->index_type, ctx); 4591f36e99a4SAndrii Nakryiko return err; 4592f36e99a4SAndrii Nakryiko } 4593f36e99a4SAndrii Nakryiko 4594f36e99a4SAndrii Nakryiko case BTF_KIND_STRUCT: 4595f36e99a4SAndrii Nakryiko case BTF_KIND_UNION: { 4596f36e99a4SAndrii Nakryiko struct btf_member *m = btf_members(t); 4597f36e99a4SAndrii Nakryiko 4598f36e99a4SAndrii Nakryiko for (i = 0, n = btf_vlen(t); i < n; i++, m++) { 4599f36e99a4SAndrii Nakryiko err = visit(&m->type, ctx); 4600f36e99a4SAndrii Nakryiko if (err) 4601f36e99a4SAndrii Nakryiko return err; 4602f36e99a4SAndrii Nakryiko } 4603f36e99a4SAndrii Nakryiko return 0; 4604f36e99a4SAndrii Nakryiko } 4605f36e99a4SAndrii Nakryiko 4606f36e99a4SAndrii Nakryiko case BTF_KIND_FUNC_PROTO: { 4607f36e99a4SAndrii Nakryiko struct btf_param *m = btf_params(t); 4608f36e99a4SAndrii Nakryiko 4609f36e99a4SAndrii Nakryiko err = visit(&t->type, ctx); 4610f36e99a4SAndrii Nakryiko if (err) 4611f36e99a4SAndrii Nakryiko return err; 4612f36e99a4SAndrii Nakryiko for (i = 0, n = btf_vlen(t); i < n; i++, m++) { 4613f36e99a4SAndrii Nakryiko err = visit(&m->type, ctx); 4614f36e99a4SAndrii Nakryiko if (err) 4615f36e99a4SAndrii Nakryiko return err; 4616f36e99a4SAndrii Nakryiko } 4617f36e99a4SAndrii Nakryiko return 0; 4618f36e99a4SAndrii Nakryiko } 4619f36e99a4SAndrii Nakryiko 4620f36e99a4SAndrii Nakryiko case BTF_KIND_DATASEC: { 4621f36e99a4SAndrii Nakryiko struct btf_var_secinfo *m = btf_var_secinfos(t); 4622f36e99a4SAndrii Nakryiko 4623f36e99a4SAndrii Nakryiko for (i = 0, n = btf_vlen(t); i < n; i++, m++) { 4624f36e99a4SAndrii Nakryiko err = visit(&m->type, ctx); 4625f36e99a4SAndrii Nakryiko if (err) 4626f36e99a4SAndrii Nakryiko return err; 4627f36e99a4SAndrii Nakryiko } 4628f36e99a4SAndrii Nakryiko return 0; 4629f36e99a4SAndrii Nakryiko } 4630f36e99a4SAndrii Nakryiko 4631f36e99a4SAndrii Nakryiko default: 4632f36e99a4SAndrii Nakryiko return -EINVAL; 4633f36e99a4SAndrii Nakryiko } 4634f36e99a4SAndrii Nakryiko } 4635f36e99a4SAndrii Nakryiko 4636f36e99a4SAndrii Nakryiko int btf_type_visit_str_offs(struct btf_type *t, str_off_visit_fn visit, void *ctx) 4637f36e99a4SAndrii Nakryiko { 4638f36e99a4SAndrii Nakryiko int i, n, err; 4639f36e99a4SAndrii Nakryiko 4640f36e99a4SAndrii Nakryiko err = visit(&t->name_off, ctx); 4641f36e99a4SAndrii Nakryiko if (err) 4642f36e99a4SAndrii Nakryiko return err; 4643f36e99a4SAndrii Nakryiko 4644f36e99a4SAndrii Nakryiko switch (btf_kind(t)) { 4645f36e99a4SAndrii Nakryiko case BTF_KIND_STRUCT: 4646f36e99a4SAndrii Nakryiko case BTF_KIND_UNION: { 4647f36e99a4SAndrii Nakryiko struct btf_member *m = btf_members(t); 4648f36e99a4SAndrii Nakryiko 4649f36e99a4SAndrii Nakryiko for (i = 0, n = btf_vlen(t); i < n; i++, m++) { 4650f36e99a4SAndrii Nakryiko err = visit(&m->name_off, ctx); 4651f36e99a4SAndrii Nakryiko if (err) 4652f36e99a4SAndrii Nakryiko return err; 4653f36e99a4SAndrii Nakryiko } 4654f36e99a4SAndrii Nakryiko break; 4655f36e99a4SAndrii Nakryiko } 4656f36e99a4SAndrii Nakryiko case BTF_KIND_ENUM: { 4657f36e99a4SAndrii Nakryiko struct btf_enum *m = btf_enum(t); 4658f36e99a4SAndrii Nakryiko 4659f36e99a4SAndrii Nakryiko for (i = 0, n = btf_vlen(t); i < n; i++, m++) { 4660f36e99a4SAndrii Nakryiko err = visit(&m->name_off, ctx); 4661f36e99a4SAndrii Nakryiko if (err) 4662f36e99a4SAndrii Nakryiko return err; 4663f36e99a4SAndrii Nakryiko } 4664f36e99a4SAndrii Nakryiko break; 4665f36e99a4SAndrii Nakryiko } 4666f36e99a4SAndrii Nakryiko case BTF_KIND_FUNC_PROTO: { 4667f36e99a4SAndrii Nakryiko struct btf_param *m = btf_params(t); 4668f36e99a4SAndrii Nakryiko 4669f36e99a4SAndrii Nakryiko for (i = 0, n = btf_vlen(t); i < n; i++, m++) { 4670f36e99a4SAndrii Nakryiko err = visit(&m->name_off, ctx); 4671f36e99a4SAndrii Nakryiko if (err) 4672f36e99a4SAndrii Nakryiko return err; 4673f36e99a4SAndrii Nakryiko } 4674f36e99a4SAndrii Nakryiko break; 4675f36e99a4SAndrii Nakryiko } 4676f36e99a4SAndrii Nakryiko default: 4677f36e99a4SAndrii Nakryiko break; 4678f36e99a4SAndrii Nakryiko } 4679f36e99a4SAndrii Nakryiko 4680f36e99a4SAndrii Nakryiko return 0; 4681f36e99a4SAndrii Nakryiko } 4682f36e99a4SAndrii Nakryiko 4683f36e99a4SAndrii Nakryiko int btf_ext_visit_type_ids(struct btf_ext *btf_ext, type_id_visit_fn visit, void *ctx) 4684f36e99a4SAndrii Nakryiko { 4685f36e99a4SAndrii Nakryiko const struct btf_ext_info *seg; 4686f36e99a4SAndrii Nakryiko struct btf_ext_info_sec *sec; 4687f36e99a4SAndrii Nakryiko int i, err; 4688f36e99a4SAndrii Nakryiko 4689f36e99a4SAndrii Nakryiko seg = &btf_ext->func_info; 4690f36e99a4SAndrii Nakryiko for_each_btf_ext_sec(seg, sec) { 4691f36e99a4SAndrii Nakryiko struct bpf_func_info_min *rec; 4692f36e99a4SAndrii Nakryiko 4693f36e99a4SAndrii Nakryiko for_each_btf_ext_rec(seg, sec, i, rec) { 4694f36e99a4SAndrii Nakryiko err = visit(&rec->type_id, ctx); 4695f36e99a4SAndrii Nakryiko if (err < 0) 4696f36e99a4SAndrii Nakryiko return err; 4697f36e99a4SAndrii Nakryiko } 4698f36e99a4SAndrii Nakryiko } 4699f36e99a4SAndrii Nakryiko 4700f36e99a4SAndrii Nakryiko seg = &btf_ext->core_relo_info; 4701f36e99a4SAndrii Nakryiko for_each_btf_ext_sec(seg, sec) { 4702f36e99a4SAndrii Nakryiko struct bpf_core_relo *rec; 4703f36e99a4SAndrii Nakryiko 4704f36e99a4SAndrii Nakryiko for_each_btf_ext_rec(seg, sec, i, rec) { 4705f36e99a4SAndrii Nakryiko err = visit(&rec->type_id, ctx); 4706f36e99a4SAndrii Nakryiko if (err < 0) 4707f36e99a4SAndrii Nakryiko return err; 4708f36e99a4SAndrii Nakryiko } 4709f36e99a4SAndrii Nakryiko } 4710f36e99a4SAndrii Nakryiko 4711f36e99a4SAndrii Nakryiko return 0; 4712f36e99a4SAndrii Nakryiko } 4713f36e99a4SAndrii Nakryiko 4714f36e99a4SAndrii Nakryiko int btf_ext_visit_str_offs(struct btf_ext *btf_ext, str_off_visit_fn visit, void *ctx) 4715f36e99a4SAndrii Nakryiko { 4716f36e99a4SAndrii Nakryiko const struct btf_ext_info *seg; 4717f36e99a4SAndrii Nakryiko struct btf_ext_info_sec *sec; 4718f36e99a4SAndrii Nakryiko int i, err; 4719f36e99a4SAndrii Nakryiko 4720f36e99a4SAndrii Nakryiko seg = &btf_ext->func_info; 4721f36e99a4SAndrii Nakryiko for_each_btf_ext_sec(seg, sec) { 4722f36e99a4SAndrii Nakryiko err = visit(&sec->sec_name_off, ctx); 4723f36e99a4SAndrii Nakryiko if (err) 4724f36e99a4SAndrii Nakryiko return err; 4725f36e99a4SAndrii Nakryiko } 4726f36e99a4SAndrii Nakryiko 4727f36e99a4SAndrii Nakryiko seg = &btf_ext->line_info; 4728f36e99a4SAndrii Nakryiko for_each_btf_ext_sec(seg, sec) { 4729f36e99a4SAndrii Nakryiko struct bpf_line_info_min *rec; 4730f36e99a4SAndrii Nakryiko 4731f36e99a4SAndrii Nakryiko err = visit(&sec->sec_name_off, ctx); 4732f36e99a4SAndrii Nakryiko if (err) 4733f36e99a4SAndrii Nakryiko return err; 4734f36e99a4SAndrii Nakryiko 4735f36e99a4SAndrii Nakryiko for_each_btf_ext_rec(seg, sec, i, rec) { 4736f36e99a4SAndrii Nakryiko err = visit(&rec->file_name_off, ctx); 4737f36e99a4SAndrii Nakryiko if (err) 4738f36e99a4SAndrii Nakryiko return err; 4739f36e99a4SAndrii Nakryiko err = visit(&rec->line_off, ctx); 4740f36e99a4SAndrii Nakryiko if (err) 4741f36e99a4SAndrii Nakryiko return err; 4742f36e99a4SAndrii Nakryiko } 4743f36e99a4SAndrii Nakryiko } 4744f36e99a4SAndrii Nakryiko 4745f36e99a4SAndrii Nakryiko seg = &btf_ext->core_relo_info; 4746f36e99a4SAndrii Nakryiko for_each_btf_ext_sec(seg, sec) { 4747f36e99a4SAndrii Nakryiko struct bpf_core_relo *rec; 4748f36e99a4SAndrii Nakryiko 4749f36e99a4SAndrii Nakryiko err = visit(&sec->sec_name_off, ctx); 4750f36e99a4SAndrii Nakryiko if (err) 4751f36e99a4SAndrii Nakryiko return err; 4752f36e99a4SAndrii Nakryiko 4753f36e99a4SAndrii Nakryiko for_each_btf_ext_rec(seg, sec, i, rec) { 4754f36e99a4SAndrii Nakryiko err = visit(&rec->access_str_off, ctx); 4755f36e99a4SAndrii Nakryiko if (err) 4756f36e99a4SAndrii Nakryiko return err; 4757f36e99a4SAndrii Nakryiko } 4758f36e99a4SAndrii Nakryiko } 4759f36e99a4SAndrii Nakryiko 4760f36e99a4SAndrii Nakryiko return 0; 4761f36e99a4SAndrii Nakryiko } 4762