1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
2 /* Copyright (c) 2018 Facebook */
9 #include "libbpf_internal.h"
11 /* make sure libbpf doesn't use kernel-only integer typedefs */
12 #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
14 struct bpf_prog_linfo {
16 void *raw_jited_linfo;
17 __u32 *nr_jited_linfo_per_func;
18 __u32 *jited_linfo_func_idx;
25 static int dissect_jited_func(struct bpf_prog_linfo *prog_linfo,
26 const __u64 *ksym_func, const __u32 *ksym_len)
28 __u32 nr_jited_func, nr_linfo;
29 const void *raw_jited_linfo;
30 const __u64 *jited_linfo;
31 __u64 last_jited_linfo;
33 * Index to raw_jited_linfo:
34 * i: Index for searching the next ksym_func
35 * prev_i: Index to the last found ksym_func
38 __u32 f; /* Index to ksym_func */
40 raw_jited_linfo = prog_linfo->raw_jited_linfo;
41 jited_linfo = raw_jited_linfo;
42 if (ksym_func[0] != *jited_linfo)
45 prog_linfo->jited_linfo_func_idx[0] = 0;
46 nr_jited_func = prog_linfo->nr_jited_func;
47 nr_linfo = prog_linfo->nr_linfo;
49 for (prev_i = 0, i = 1, f = 1;
50 i < nr_linfo && f < nr_jited_func;
52 raw_jited_linfo += prog_linfo->jited_rec_size;
53 last_jited_linfo = *jited_linfo;
54 jited_linfo = raw_jited_linfo;
56 if (ksym_func[f] == *jited_linfo) {
57 prog_linfo->jited_linfo_func_idx[f] = i;
60 if (last_jited_linfo - ksym_func[f - 1] + 1 >
64 prog_linfo->nr_jited_linfo_per_func[f - 1] =
69 * The ksym_func[f] is found in jited_linfo.
70 * Look for the next one.
73 } else if (*jited_linfo <= last_jited_linfo) {
74 /* Ensure the addr is increasing _within_ a func */
79 if (f != nr_jited_func)
82 prog_linfo->nr_jited_linfo_per_func[nr_jited_func - 1] =
91 void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo)
96 free(prog_linfo->raw_linfo);
97 free(prog_linfo->raw_jited_linfo);
98 free(prog_linfo->nr_jited_linfo_per_func);
99 free(prog_linfo->jited_linfo_func_idx);
103 struct bpf_prog_linfo *bpf_prog_linfo__new(const struct bpf_prog_info *info)
105 struct bpf_prog_linfo *prog_linfo;
106 __u32 nr_linfo, nr_jited_func;
109 nr_linfo = info->nr_line_info;
115 * The min size that bpf_prog_linfo has to access for
118 if (info->line_info_rec_size <
119 offsetof(struct bpf_line_info, file_name_off))
122 prog_linfo = calloc(1, sizeof(*prog_linfo));
126 /* Copy xlated line_info */
127 prog_linfo->nr_linfo = nr_linfo;
128 prog_linfo->rec_size = info->line_info_rec_size;
129 data_sz = (__u64)nr_linfo * prog_linfo->rec_size;
130 prog_linfo->raw_linfo = malloc(data_sz);
131 if (!prog_linfo->raw_linfo)
133 memcpy(prog_linfo->raw_linfo, (void *)(long)info->line_info, data_sz);
135 nr_jited_func = info->nr_jited_ksyms;
136 if (!nr_jited_func ||
137 !info->jited_line_info ||
138 info->nr_jited_line_info != nr_linfo ||
139 info->jited_line_info_rec_size < sizeof(__u64) ||
140 info->nr_jited_func_lens != nr_jited_func ||
141 !info->jited_ksyms ||
142 !info->jited_func_lens)
143 /* Not enough info to provide jited_line_info */
146 /* Copy jited_line_info */
147 prog_linfo->nr_jited_func = nr_jited_func;
148 prog_linfo->jited_rec_size = info->jited_line_info_rec_size;
149 data_sz = (__u64)nr_linfo * prog_linfo->jited_rec_size;
150 prog_linfo->raw_jited_linfo = malloc(data_sz);
151 if (!prog_linfo->raw_jited_linfo)
153 memcpy(prog_linfo->raw_jited_linfo,
154 (void *)(long)info->jited_line_info, data_sz);
156 /* Number of jited_line_info per jited func */
157 prog_linfo->nr_jited_linfo_per_func = malloc(nr_jited_func *
159 if (!prog_linfo->nr_jited_linfo_per_func)
163 * For each jited func,
164 * the start idx to the "linfo" and "jited_linfo" array,
166 prog_linfo->jited_linfo_func_idx = malloc(nr_jited_func *
168 if (!prog_linfo->jited_linfo_func_idx)
171 if (dissect_jited_func(prog_linfo,
172 (__u64 *)(long)info->jited_ksyms,
173 (__u32 *)(long)info->jited_func_lens))
179 bpf_prog_linfo__free(prog_linfo);
183 const struct bpf_line_info *
184 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
185 __u64 addr, __u32 func_idx, __u32 nr_skip)
187 __u32 jited_rec_size, rec_size, nr_linfo, start, i;
188 const void *raw_jited_linfo, *raw_linfo;
189 const __u64 *jited_linfo;
191 if (func_idx >= prog_linfo->nr_jited_func)
194 nr_linfo = prog_linfo->nr_jited_linfo_per_func[func_idx];
195 if (nr_skip >= nr_linfo)
198 start = prog_linfo->jited_linfo_func_idx[func_idx] + nr_skip;
199 jited_rec_size = prog_linfo->jited_rec_size;
200 raw_jited_linfo = prog_linfo->raw_jited_linfo +
201 (start * jited_rec_size);
202 jited_linfo = raw_jited_linfo;
203 if (addr < *jited_linfo)
207 rec_size = prog_linfo->rec_size;
208 raw_linfo = prog_linfo->raw_linfo + (start * rec_size);
209 for (i = 0; i < nr_linfo; i++) {
210 if (addr < *jited_linfo)
213 raw_linfo += rec_size;
214 raw_jited_linfo += jited_rec_size;
215 jited_linfo = raw_jited_linfo;
218 return raw_linfo - rec_size;
221 const struct bpf_line_info *
222 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
223 __u32 insn_off, __u32 nr_skip)
225 const struct bpf_line_info *linfo;
226 __u32 rec_size, nr_linfo, i;
227 const void *raw_linfo;
229 nr_linfo = prog_linfo->nr_linfo;
230 if (nr_skip >= nr_linfo)
233 rec_size = prog_linfo->rec_size;
234 raw_linfo = prog_linfo->raw_linfo + (nr_skip * rec_size);
236 if (insn_off < linfo->insn_off)
240 for (i = 0; i < nr_linfo; i++) {
241 if (insn_off < linfo->insn_off)
244 raw_linfo += rec_size;
248 return raw_linfo - rec_size;