| 1 | |
| 2 |
|
| 3 |
|
| 4 | #ifndef _GNU_SOURCE
|
| 5 | #define _GNU_SOURCE
|
| 6 | #endif
|
| 7 | #include <ctype.h>
|
| 8 | #include <errno.h>
|
| 9 | #include <fcntl.h>
|
| 10 | #include <libgen.h>
|
| 11 | #include <linux/err.h>
|
| 12 | #include <stdbool.h>
|
| 13 | #include <stdio.h>
|
| 14 | #include <string.h>
|
| 15 | #include <unistd.h>
|
| 16 | #include <bpf/bpf.h>
|
| 17 | #include <bpf/libbpf.h>
|
| 18 | #include <bpf/libbpf_internal.h>
|
| 19 | #include <sys/types.h>
|
| 20 | #include <sys/stat.h>
|
| 21 | #include <sys/mman.h>
|
| 22 | #include <bpf/btf.h>
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| 23 |
|
| 24 | #include "json_writer.h"
|
| 25 | #include "main.h"
|
| 26 |
|
| 27 | #define MAX_OBJ_NAME_LEN 64
|
| 28 |
|
| 29 | static void sanitize_identifier(char *name)
|
| 30 | {
|
| 31 | int i;
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| 32 |
|
| 33 | for (i = 0; name[i]; i++)
|
| 34 | if (!isalnum(name[i]) && name[i] != '_')
|
| 35 | name[i] = '_';
|
| 36 | }
|
| 37 |
|
| 38 | static bool str_has_prefix(const char *str, const char *prefix)
|
| 39 | {
|
| 40 | return strncmp(str, prefix, strlen(prefix)) == 0;
|
| 41 | }
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| 42 |
|
| 43 | static bool str_has_suffix(const char *str, const char *suffix)
|
| 44 | {
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| 45 | size_t i, n1 = strlen(str), n2 = strlen(suffix);
|
| 46 |
|
| 47 | if (n1 < n2)
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| 48 | return false;
|
| 49 |
|
| 50 | for (i = 0; i < n2; i++) {
|
| 51 | if (str[n1 - i - 1] != suffix[n2 - i - 1])
|
| 52 | return false;
|
| 53 | }
|
| 54 |
|
| 55 | return true;
|
| 56 | }
|
| 57 |
|
| 58 | static const struct btf_type *
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| 59 | resolve_func_ptr(const struct btf *btf, __u32 id, __u32 *res_id)
|
| 60 | {
|
| 61 | const struct btf_type *t;
|
| 62 |
|
| 63 | t = skip_mods_and_typedefs(btf, id, NULL);
|
| 64 | if (!btf_is_ptr(t))
|
| 65 | return NULL;
|
| 66 |
|
| 67 | t = skip_mods_and_typedefs(btf, t->type, res_id);
|
| 68 |
|
| 69 | return btf_is_func_proto(t) ? t : NULL;
|
| 70 | }
|
| 71 |
|
| 72 | static void get_obj_name(char *name, const char *file)
|
| 73 | {
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| 74 | char file_copy[PATH_MAX];
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| 75 |
|
| 76 |
|
| 77 | strncpy(file_copy, file, PATH_MAX - 1)[PATH_MAX - 1] = '\0';
|
| 78 | strncpy(name, basename(file_copy), MAX_OBJ_NAME_LEN - 1)[MAX_OBJ_NAME_LEN - 1] = '\0';
|
| 79 | if (str_has_suffix(name, ".o"))
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| 80 | name[strlen(name) - 2] = '\0';
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| 81 | sanitize_identifier(name);
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| 82 | }
|
| 83 |
|
| 84 | static void get_header_guard(char *guard, const char *obj_name, const char *suffix)
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| 85 | {
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| 86 | int i;
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| 87 |
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| 88 | sprintf(guard, "__%s_%s__", obj_name, suffix);
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| 89 | for (i = 0; guard[i]; i++)
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| 90 | guard[i] = toupper(guard[i]);
|
| 91 | }
|
| 92 |
|
| 93 | static bool get_map_ident(const struct bpf_map *map, char *buf, size_t buf_sz)
|
| 94 | {
|
| 95 | static const char *sfxs[] = { ".data", ".rodata", ".bss", ".kconfig" };
|
| 96 | const char *name = bpf_map__name(map);
|
| 97 | int i, n;
|
| 98 |
|
| 99 | if (!bpf_map__is_internal(map)) {
|
| 100 | snprintf(buf, buf_sz, "%s", name);
|
| 101 | return true;
|
| 102 | }
|
| 103 |
|
| 104 | if (bpf_map__type(map) == BPF_MAP_TYPE_PERCPU_ARRAY) {
|
| 105 | snprintf(buf, buf_sz, "%s", name + 1);
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| 106 | sanitize_identifier(buf);
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| 107 | return true;
|
| 108 | }
|
| 109 |
|
| 110 | for (i = 0, n = ARRAY_SIZE(sfxs); i < n; i++) {
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| 111 | const char *sfx = sfxs[i], *p;
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| 112 |
|
| 113 | p = strstr(name, sfx);
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| 114 | if (p) {
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| 115 | snprintf(buf, buf_sz, "%s", p + 1);
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| 116 | sanitize_identifier(buf);
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| 117 | return true;
|
| 118 | }
|
| 119 | }
|
| 120 |
|
| 121 | return false;
|
| 122 | }
|
| 123 |
|
| 124 | static bool get_datasec_ident(const char *sec_name, char *buf, size_t buf_sz)
|
| 125 | {
|
| 126 | static const char *pfxs[] = { ".data", ".rodata", ".bss", ".percpu", ".kconfig" };
|
| 127 | int i, n;
|
| 128 |
|
| 129 |
|
| 130 | if (strcmp(sec_name, ".addr_space.1") == 0) {
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| 131 |
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| 132 | snprintf(buf, buf_sz, "arena");
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| 133 | return true;
|
| 134 | }
|
| 135 | for (i = 0, n = ARRAY_SIZE(pfxs); i < n; i++) {
|
| 136 | const char *pfx = pfxs[i];
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| 137 |
|
| 138 | if (str_has_prefix(sec_name, pfx)) {
|
| 139 | snprintf(buf, buf_sz, "%s", sec_name + 1);
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| 140 | sanitize_identifier(buf);
|
| 141 | return true;
|
| 142 | }
|
| 143 | }
|
| 144 |
|
| 145 | return false;
|
| 146 | }
|
| 147 |
|
| 148 | static void codegen_btf_dump_printf(void *ctx, const char *fmt, va_list args)
|
| 149 | {
|
| 150 | vprintf(fmt, args);
|
| 151 | }
|
| 152 |
|
| 153 | static int codegen_datasec_def(struct bpf_object *obj,
|
| 154 | struct btf *btf,
|
| 155 | struct btf_dump *d,
|
| 156 | const struct btf_type *sec,
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| 157 | const char *obj_name)
|
| 158 | {
|
| 159 | const char *sec_name = btf__name_by_offset(btf, sec->name_off);
|
| 160 | const struct btf_var_secinfo *sec_var = btf_var_secinfos(sec);
|
| 161 | int i, err, off = 0, pad_cnt = 0, vlen = btf_vlen(sec);
|
| 162 | char var_ident[256], sec_ident[256];
|
| 163 | bool strip_mods = false;
|
| 164 |
|
| 165 | if (!get_datasec_ident(sec_name, sec_ident, sizeof(sec_ident)))
|
| 166 | return 0;
|
| 167 |
|
| 168 | if (strcmp(sec_name, ".kconfig") != 0)
|
| 169 | strip_mods = true;
|
| 170 |
|
| 171 | printf(" struct %s__%s {\n", obj_name, sec_ident);
|
| 172 | for (i = 0; i < vlen; i++, sec_var++) {
|
| 173 | const struct btf_type *var = btf__type_by_id(btf, sec_var->type);
|
| 174 | const char *var_name = btf__name_by_offset(btf, var->name_off);
|
| 175 | DECLARE_LIBBPF_OPTS(btf_dump_emit_type_decl_opts, opts,
|
| 176 | .field_name = var_ident,
|
| 177 | .indent_level = 2,
|
| 178 | .strip_mods = strip_mods,
|
| 179 | );
|
| 180 | int need_off = sec_var->offset, align_off, align;
|
| 181 | __u32 var_type_id = var->type;
|
| 182 |
|
| 183 |
|
| 184 | if (btf_var(var)->linkage == BTF_VAR_STATIC)
|
| 185 | continue;
|
| 186 |
|
| 187 | if (off > need_off) {
|
| 188 | p_err("Something is wrong for %s's variable #%d: need offset %d, already at %d.\n",
|
| 189 | sec_name, i, need_off, off);
|
| 190 | return -EINVAL;
|
| 191 | }
|
| 192 |
|
| 193 | align = btf__align_of(btf, var->type);
|
| 194 | if (align <= 0) {
|
| 195 | p_err("Failed to determine alignment of variable '%s': %d",
|
| 196 | var_name, align);
|
| 197 | return -EINVAL;
|
| 198 | }
|
| 199 | |
| 200 | * struct memory layout. Given bpftool can't know which target
|
| 201 | * host architecture it's emitting skeleton for, we need to be
|
| 202 | * conservative and assume 32-bit one to ensure enough padding
|
| 203 | * bytes are generated for pointer and long types. This will
|
| 204 | * still work correctly for 64-bit architectures, because in
|
| 205 | * the worst case we'll generate unnecessary padding field,
|
| 206 | * which on 64-bit architectures is not strictly necessary and
|
| 207 | * would be handled by natural 8-byte alignment. But it still
|
| 208 | * will be a correct memory layout, based on recorded offsets
|
| 209 | * in BTF.
|
| 210 |
|
| 211 | if (align > 4)
|
| 212 | align = 4;
|
| 213 |
|
| 214 | align_off = (off + align - 1) / align * align;
|
| 215 | if (align_off != need_off) {
|
| 216 | printf("\t\tchar __pad%d[%d];\n",
|
| 217 | pad_cnt, need_off - off);
|
| 218 | pad_cnt++;
|
| 219 | }
|
| 220 |
|
| 221 | |
| 222 | * a function, it's name is '<function name>.<variable name>',
|
| 223 | * which we'll turn into a '<function name>_<variable name>'
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| 224 |
|
| 225 | var_ident[0] = '\0';
|
| 226 | strncat(var_ident, var_name, sizeof(var_ident) - 1);
|
| 227 | sanitize_identifier(var_ident);
|
| 228 |
|
| 229 | printf("\t\t");
|
| 230 | err = btf_dump__emit_type_decl(d, var_type_id, &opts);
|
| 231 | if (err)
|
| 232 | return err;
|
| 233 | printf(";\n");
|
| 234 |
|
| 235 | off = sec_var->offset + sec_var->size;
|
| 236 | }
|
| 237 | printf(" } *%s;\n", sec_ident);
|
| 238 | return 0;
|
| 239 | }
|
| 240 |
|
| 241 | static const struct btf_type *find_type_for_map(struct btf *btf, const char *map_ident)
|
| 242 | {
|
| 243 | int n = btf__type_cnt(btf), i;
|
| 244 | char sec_ident[256];
|
| 245 |
|
| 246 | for (i = 1; i < n; i++) {
|
| 247 | const struct btf_type *t = btf__type_by_id(btf, i);
|
| 248 | const char *name;
|
| 249 |
|
| 250 | if (!btf_is_datasec(t))
|
| 251 | continue;
|
| 252 |
|
| 253 | name = btf__str_by_offset(btf, t->name_off);
|
| 254 | if (!get_datasec_ident(name, sec_ident, sizeof(sec_ident)))
|
| 255 | continue;
|
| 256 |
|
| 257 | if (strcmp(sec_ident, map_ident) == 0)
|
| 258 | return t;
|
| 259 | }
|
| 260 | return NULL;
|
| 261 | }
|
| 262 |
|
| 263 | static bool is_skel_data(const struct bpf_map *map, char *buf, size_t sz)
|
| 264 | {
|
| 265 | size_t tmp_sz;
|
| 266 |
|
| 267 | if (bpf_map__type(map) == BPF_MAP_TYPE_ARENA && bpf_map__initial_value(map, &tmp_sz)) {
|
| 268 | snprintf(buf, sz, "arena");
|
| 269 | return true;
|
| 270 | }
|
| 271 |
|
| 272 | if (!bpf_map__is_internal(map))
|
| 273 | return false;
|
| 274 |
|
| 275 | if (!get_map_ident(map, buf, sz))
|
| 276 | return false;
|
| 277 |
|
| 278 | if (bpf_map__map_flags(map) & BPF_F_MMAPABLE)
|
| 279 | return true;
|
| 280 |
|
| 281 | if (bpf_map__type(map) == BPF_MAP_TYPE_PERCPU_ARRAY)
|
| 282 | return bpf_map__btf_value_type_id(map) != 0;
|
| 283 |
|
| 284 | return false;
|
| 285 | }
|
| 286 |
|
| 287 | static bool is_mmapable_map(const struct bpf_map *map, char *buf, size_t sz)
|
| 288 | {
|
| 289 | return is_skel_data(map, buf, sz) && bpf_map__type(map) != BPF_MAP_TYPE_PERCPU_ARRAY;
|
| 290 | }
|
| 291 |
|
| 292 | static int codegen_datasecs(struct bpf_object *obj, const char *obj_name)
|
| 293 | {
|
| 294 | struct btf *btf = bpf_object__btf(obj);
|
| 295 | struct btf_dump *d;
|
| 296 | struct bpf_map *map;
|
| 297 | const struct btf_type *sec;
|
| 298 | char map_ident[256];
|
| 299 | int err = 0;
|
| 300 |
|
| 301 | d = btf_dump__new(btf, codegen_btf_dump_printf, NULL, NULL);
|
| 302 | if (!d)
|
| 303 | return -errno;
|
| 304 |
|
| 305 | bpf_object__for_each_map(map, obj) {
|
| 306 |
|
| 307 | if (!is_skel_data(map, map_ident, sizeof(map_ident)))
|
| 308 | continue;
|
| 309 |
|
| 310 | sec = find_type_for_map(btf, map_ident);
|
| 311 |
|
| 312 | |
| 313 | * compiler allocated string constants only) there will be
|
| 314 | * special internal maps with no corresponding DATASEC BTF
|
| 315 | * type. In such case, generate empty structs for each such
|
| 316 | * map. It will still be memory-mapped and its contents
|
| 317 | * accessible from user-space through BPF skeleton.
|
| 318 |
|
| 319 | if (!sec) {
|
| 320 | printf(" struct %s__%s {\n", obj_name, map_ident);
|
| 321 | printf(" } *%s;\n", map_ident);
|
| 322 | } else {
|
| 323 | err = codegen_datasec_def(obj, btf, d, sec, obj_name);
|
| 324 | if (err)
|
| 325 | goto out;
|
| 326 | }
|
| 327 | }
|
| 328 |
|
| 329 |
|
| 330 | out:
|
| 331 | btf_dump__free(d);
|
| 332 | return err;
|
| 333 | }
|
| 334 |
|
| 335 | static bool btf_is_ptr_to_func_proto(const struct btf *btf,
|
| 336 | const struct btf_type *v)
|
| 337 | {
|
| 338 | return btf_is_ptr(v) && btf_is_func_proto(btf__type_by_id(btf, v->type));
|
| 339 | }
|
| 340 |
|
| 341 | static int codegen_subskel_datasecs(struct bpf_object *obj, const char *obj_name)
|
| 342 | {
|
| 343 | struct btf *btf = bpf_object__btf(obj);
|
| 344 | struct btf_dump *d;
|
| 345 | struct bpf_map *map;
|
| 346 | const struct btf_type *sec, *var;
|
| 347 | const struct btf_var_secinfo *sec_var;
|
| 348 | int i, err = 0, vlen;
|
| 349 | char map_ident[256], sec_ident[256];
|
| 350 | bool strip_mods = false, needs_typeof = false;
|
| 351 | const char *sec_name, *var_name;
|
| 352 | __u32 var_type_id;
|
| 353 |
|
| 354 | d = btf_dump__new(btf, codegen_btf_dump_printf, NULL, NULL);
|
| 355 | if (!d)
|
| 356 | return -errno;
|
| 357 |
|
| 358 | bpf_object__for_each_map(map, obj) {
|
| 359 |
|
| 360 | if (!is_mmapable_map(map, map_ident, sizeof(map_ident)))
|
| 361 | continue;
|
| 362 |
|
| 363 | sec = find_type_for_map(btf, map_ident);
|
| 364 | if (!sec)
|
| 365 | continue;
|
| 366 |
|
| 367 | sec_name = btf__name_by_offset(btf, sec->name_off);
|
| 368 | if (!get_datasec_ident(sec_name, sec_ident, sizeof(sec_ident)))
|
| 369 | continue;
|
| 370 |
|
| 371 | strip_mods = strcmp(sec_name, ".kconfig") != 0;
|
| 372 | printf(" struct %s__%s {\n", obj_name, sec_ident);
|
| 373 |
|
| 374 | sec_var = btf_var_secinfos(sec);
|
| 375 | vlen = btf_vlen(sec);
|
| 376 | for (i = 0; i < vlen; i++, sec_var++) {
|
| 377 | DECLARE_LIBBPF_OPTS(btf_dump_emit_type_decl_opts, opts,
|
| 378 | .indent_level = 2,
|
| 379 | .strip_mods = strip_mods,
|
| 380 |
|
| 381 | .field_name = "",
|
| 382 | );
|
| 383 |
|
| 384 | var = btf__type_by_id(btf, sec_var->type);
|
| 385 | var_name = btf__name_by_offset(btf, var->name_off);
|
| 386 | var_type_id = var->type;
|
| 387 |
|
| 388 |
|
| 389 | if (btf_var(var)->linkage == BTF_VAR_STATIC)
|
| 390 | continue;
|
| 391 |
|
| 392 | |
| 393 | * underlying type of the variable (e.g. KIND_INT).
|
| 394 |
|
| 395 | var = skip_mods_and_typedefs(btf, var->type, NULL);
|
| 396 |
|
| 397 | printf("\t\t");
|
| 398 | |
| 399 | * Instead of producing `typename *var`, they produce
|
| 400 | * `typeof(typename) *var`. This allows us to keep a
|
| 401 | * similar syntax where the identifier is just prefixed
|
| 402 | * by *, allowing us to ignore C declaration minutiae.
|
| 403 |
|
| 404 | needs_typeof = btf_is_array(var) || btf_is_ptr_to_func_proto(btf, var);
|
| 405 | if (needs_typeof)
|
| 406 | printf("__typeof__(");
|
| 407 |
|
| 408 | err = btf_dump__emit_type_decl(d, var_type_id, &opts);
|
| 409 | if (err)
|
| 410 | goto out;
|
| 411 |
|
| 412 | if (needs_typeof)
|
| 413 | printf(")");
|
| 414 |
|
| 415 | printf(" *%s;\n", var_name);
|
| 416 | }
|
| 417 | printf(" } %s;\n", sec_ident);
|
| 418 | }
|
| 419 |
|
| 420 | out:
|
| 421 | btf_dump__free(d);
|
| 422 | return err;
|
| 423 | }
|
| 424 |
|
| 425 | static void codegen(const char *template, ...)
|
| 426 | {
|
| 427 | const char *src, *end;
|
| 428 | int skip_tabs = 0, n;
|
| 429 | char *s, *dst;
|
| 430 | va_list args;
|
| 431 | char c;
|
| 432 |
|
| 433 | n = strlen(template);
|
| 434 | s = malloc(n + 1);
|
| 435 | if (!s)
|
| 436 | exit(-1);
|
| 437 | src = template;
|
| 438 | dst = s;
|
| 439 |
|
| 440 |
|
| 441 | while ((c = *src++)) {
|
| 442 | if (c == '\t') {
|
| 443 | skip_tabs++;
|
| 444 | } else if (c == '\n') {
|
| 445 | break;
|
| 446 | } else {
|
| 447 | p_err("unrecognized character at pos %td in template '%s': '%c'",
|
| 448 | src - template - 1, template, c);
|
| 449 | free(s);
|
| 450 | exit(-1);
|
| 451 | }
|
| 452 | }
|
| 453 |
|
| 454 | while (*src) {
|
| 455 |
|
| 456 | for (n = skip_tabs; n > 0; n--, src++) {
|
| 457 | if (*src != '\t') {
|
| 458 | p_err("not enough tabs at pos %td in template '%s'",
|
| 459 | src - template - 1, template);
|
| 460 | free(s);
|
| 461 | exit(-1);
|
| 462 | }
|
| 463 | }
|
| 464 |
|
| 465 | end = strchrnul(src, '\n');
|
| 466 | for (n = end - src; n > 0 && isspace(src[n - 1]); n--)
|
| 467 | ;
|
| 468 | memcpy(dst, src, n);
|
| 469 | dst += n;
|
| 470 | if (*end)
|
| 471 | *dst++ = '\n';
|
| 472 | src = *end ? end + 1 : end;
|
| 473 | }
|
| 474 | *dst++ = '\0';
|
| 475 |
|
| 476 |
|
| 477 | va_start(args, template);
|
| 478 | n = vprintf(s, args);
|
| 479 | va_end(args);
|
| 480 |
|
| 481 | free(s);
|
| 482 | }
|
| 483 |
|
| 484 | static void print_hex(const char *data, int data_sz)
|
| 485 | {
|
| 486 | int i, len;
|
| 487 |
|
| 488 | for (i = 0, len = 0; i < data_sz; i++) {
|
| 489 | int w = data[i] ? 4 : 2;
|
| 490 |
|
| 491 | len += w;
|
| 492 | if (len > 78) {
|
| 493 | printf("\\\n");
|
| 494 | len = w;
|
| 495 | }
|
| 496 | if (!data[i])
|
| 497 | printf("\\0");
|
| 498 | else
|
| 499 | printf("\\x%02x", (unsigned char)data[i]);
|
| 500 | }
|
| 501 | }
|
| 502 |
|
| 503 | static size_t bpf_map_mmap_sz(const struct bpf_map *map)
|
| 504 | {
|
| 505 | long page_sz = sysconf(_SC_PAGE_SIZE);
|
| 506 | size_t map_sz;
|
| 507 |
|
| 508 | map_sz = (size_t)roundup(bpf_map__value_size(map), 8) * bpf_map__max_entries(map);
|
| 509 | map_sz = roundup(map_sz, page_sz);
|
| 510 | return map_sz;
|
| 511 | }
|
| 512 |
|
| 513 |
|
| 514 | static void codegen_asserts(struct bpf_object *obj, const char *obj_name)
|
| 515 | {
|
| 516 | struct btf *btf = bpf_object__btf(obj);
|
| 517 | struct bpf_map *map;
|
| 518 | struct btf_var_secinfo *sec_var;
|
| 519 | int i, vlen;
|
| 520 | const struct btf_type *sec;
|
| 521 | char map_ident[256], var_ident[256];
|
| 522 |
|
| 523 | if (!btf)
|
| 524 | return;
|
| 525 |
|
| 526 | codegen("\
|
| 527 | \n\
|
| 528 | __attribute__((unused)) static void \n\
|
| 529 | %1$s__assert(struct %1$s *s __attribute__((unused))) \n\
|
| 530 | { \n\
|
| 531 | #ifdef __cplusplus \n\
|
| 532 | #define _Static_assert static_assert \n\
|
| 533 | #endif \n\
|
| 534 | ", obj_name);
|
| 535 |
|
| 536 | bpf_object__for_each_map(map, obj) {
|
| 537 | if (!is_skel_data(map, map_ident, sizeof(map_ident)))
|
| 538 | continue;
|
| 539 |
|
| 540 | sec = find_type_for_map(btf, map_ident);
|
| 541 | if (!sec) {
|
| 542 |
|
| 543 | continue;
|
| 544 | }
|
| 545 |
|
| 546 | sec_var = btf_var_secinfos(sec);
|
| 547 | vlen = btf_vlen(sec);
|
| 548 |
|
| 549 | for (i = 0; i < vlen; i++, sec_var++) {
|
| 550 | const struct btf_type *var = btf__type_by_id(btf, sec_var->type);
|
| 551 | const char *var_name = btf__name_by_offset(btf, var->name_off);
|
| 552 | long var_size;
|
| 553 |
|
| 554 |
|
| 555 | if (btf_var(var)->linkage == BTF_VAR_STATIC)
|
| 556 | continue;
|
| 557 |
|
| 558 | var_size = btf__resolve_size(btf, var->type);
|
| 559 | if (var_size < 0)
|
| 560 | continue;
|
| 561 |
|
| 562 | var_ident[0] = '\0';
|
| 563 | strncat(var_ident, var_name, sizeof(var_ident) - 1);
|
| 564 | sanitize_identifier(var_ident);
|
| 565 |
|
| 566 | printf("\t_Static_assert(sizeof(s->%s->%s) == %ld, \"unexpected size of '%s'\");\n",
|
| 567 | map_ident, var_ident, var_size, var_ident);
|
| 568 | }
|
| 569 | }
|
| 570 | codegen("\
|
| 571 | \n\
|
| 572 | #ifdef __cplusplus \n\
|
| 573 | #undef _Static_assert \n\
|
| 574 | #endif \n\
|
| 575 | } \n\
|
| 576 | ");
|
| 577 | }
|
| 578 |
|
| 579 | static void codegen_attach_detach(struct bpf_object *obj, const char *obj_name)
|
| 580 | {
|
| 581 | struct bpf_program *prog;
|
| 582 |
|
| 583 | bpf_object__for_each_program(prog, obj) {
|
| 584 | const char *tp_name;
|
| 585 |
|
| 586 | codegen("\
|
| 587 | \n\
|
| 588 | \n\
|
| 589 | static inline int \n\
|
| 590 | %1$s__%2$s__attach(struct %1$s *skel) \n\
|
| 591 | { \n\
|
| 592 | int prog_fd = skel->progs.%2$s.prog_fd; \n\
|
| 593 | ", obj_name, bpf_program__name(prog));
|
| 594 |
|
| 595 | switch (bpf_program__type(prog)) {
|
| 596 | case BPF_PROG_TYPE_RAW_TRACEPOINT:
|
| 597 | tp_name = strchr(bpf_program__section_name(prog), '/') + 1;
|
| 598 | printf("\tint fd = skel_raw_tracepoint_open(\"%s\", prog_fd);\n", tp_name);
|
| 599 | break;
|
| 600 | case BPF_PROG_TYPE_TRACING:
|
| 601 | case BPF_PROG_TYPE_LSM:
|
| 602 | if (bpf_program__expected_attach_type(prog) == BPF_TRACE_ITER)
|
| 603 | printf("\tint fd = skel_link_create(prog_fd, 0, BPF_TRACE_ITER);\n");
|
| 604 | else
|
| 605 | printf("\tint fd = skel_raw_tracepoint_open(NULL, prog_fd);\n");
|
| 606 | break;
|
| 607 | default:
|
| 608 | printf("\tint fd = ((void)prog_fd, 0); /* auto-attach not supported */\n");
|
| 609 | break;
|
| 610 | }
|
| 611 | codegen("\
|
| 612 | \n\
|
| 613 | \n\
|
| 614 | if (fd > 0) \n\
|
| 615 | skel->links.%1$s_fd = fd; \n\
|
| 616 | return fd; \n\
|
| 617 | } \n\
|
| 618 | ", bpf_program__name(prog));
|
| 619 | }
|
| 620 |
|
| 621 | codegen("\
|
| 622 | \n\
|
| 623 | \n\
|
| 624 | static inline int \n\
|
| 625 | %1$s__attach(struct %1$s *skel) \n\
|
| 626 | { \n\
|
| 627 | int ret = 0; \n\
|
| 628 | \n\
|
| 629 | ", obj_name);
|
| 630 |
|
| 631 | bpf_object__for_each_program(prog, obj) {
|
| 632 | codegen("\
|
| 633 | \n\
|
| 634 | ret = ret < 0 ? ret : %1$s__%2$s__attach(skel); \n\
|
| 635 | ", obj_name, bpf_program__name(prog));
|
| 636 | }
|
| 637 |
|
| 638 | codegen("\
|
| 639 | \n\
|
| 640 | return ret < 0 ? ret : 0; \n\
|
| 641 | } \n\
|
| 642 | \n\
|
| 643 | static inline void \n\
|
| 644 | %1$s__detach(struct %1$s *skel) \n\
|
| 645 | { \n\
|
| 646 | ", obj_name);
|
| 647 |
|
| 648 | bpf_object__for_each_program(prog, obj) {
|
| 649 | codegen("\
|
| 650 | \n\
|
| 651 | skel_closenz(skel->links.%1$s_fd); \n\
|
| 652 | ", bpf_program__name(prog));
|
| 653 | }
|
| 654 |
|
| 655 | codegen("\
|
| 656 | \n\
|
| 657 | } \n\
|
| 658 | ");
|
| 659 | }
|
| 660 |
|
| 661 | static void codegen_destroy(struct bpf_object *obj, const char *obj_name)
|
| 662 | {
|
| 663 | struct bpf_program *prog;
|
| 664 | struct bpf_map *map;
|
| 665 | char ident[256];
|
| 666 |
|
| 667 | codegen("\
|
| 668 | \n\
|
| 669 | static void \n\
|
| 670 | %1$s__destroy(struct %1$s *skel) \n\
|
| 671 | { \n\
|
| 672 | if (!skel) \n\
|
| 673 | return; \n\
|
| 674 | %1$s__detach(skel); \n\
|
| 675 | ",
|
| 676 | obj_name);
|
| 677 |
|
| 678 | bpf_object__for_each_program(prog, obj) {
|
| 679 | codegen("\
|
| 680 | \n\
|
| 681 | skel_closenz(skel->progs.%1$s.prog_fd); \n\
|
| 682 | ", bpf_program__name(prog));
|
| 683 | }
|
| 684 |
|
| 685 | bpf_object__for_each_map(map, obj) {
|
| 686 | if (!get_map_ident(map, ident, sizeof(ident)))
|
| 687 | continue;
|
| 688 | if (is_skel_data(map, ident, sizeof(ident)))
|
| 689 | printf("\tskel_free_map_data(skel->%1$s, skel->maps.%1$s.initial_value, %2$zu);\n",
|
| 690 | ident, bpf_map_mmap_sz(map));
|
| 691 | codegen("\
|
| 692 | \n\
|
| 693 | skel_closenz(skel->maps.%1$s.map_fd); \n\
|
| 694 | ", ident);
|
| 695 | }
|
| 696 | codegen("\
|
| 697 | \n\
|
| 698 | skel_free(skel); \n\
|
| 699 | } \n\
|
| 700 | ",
|
| 701 | obj_name);
|
| 702 | }
|
| 703 |
|
| 704 | static int gen_trace(struct bpf_object *obj, const char *obj_name, const char *header_guard)
|
| 705 | {
|
| 706 | DECLARE_LIBBPF_OPTS(gen_loader_opts, opts);
|
| 707 | struct bpf_load_and_run_opts sopts = {};
|
| 708 | char sig_buf[MAX_SIG_SIZE];
|
| 709 | __u8 prog_sha[SHA256_DIGEST_LENGTH];
|
| 710 | struct bpf_map *map;
|
| 711 |
|
| 712 | char ident[256];
|
| 713 | int err = 0;
|
| 714 |
|
| 715 | if (sign_progs)
|
| 716 | opts.gen_hash = true;
|
| 717 |
|
| 718 | err = bpf_object__gen_loader(obj, &opts);
|
| 719 | if (err)
|
| 720 | return err;
|
| 721 |
|
| 722 | err = bpf_object__load(obj);
|
| 723 | if (err) {
|
| 724 | p_err("failed to load object file");
|
| 725 | goto out;
|
| 726 | }
|
| 727 |
|
| 728 | |
| 729 | * are populated with the loader program.
|
| 730 |
|
| 731 |
|
| 732 |
|
| 733 | codegen("\
|
| 734 | \n\
|
| 735 | }; \n\
|
| 736 | ", obj_name);
|
| 737 |
|
| 738 |
|
| 739 | codegen_attach_detach(obj, obj_name);
|
| 740 |
|
| 741 | codegen_destroy(obj, obj_name);
|
| 742 |
|
| 743 | codegen("\
|
| 744 | \n\
|
| 745 | static inline struct %1$s * \n\
|
| 746 | %1$s__open(void) \n\
|
| 747 | { \n\
|
| 748 | struct %1$s *skel; \n\
|
| 749 | \n\
|
| 750 | skel = (struct %1$s *)skel_alloc(sizeof(*skel)); \n\
|
| 751 | if (!skel) \n\
|
| 752 | goto cleanup; \n\
|
| 753 | skel->ctx.sz = (char *)&skel->links - (char *)skel; \n\
|
| 754 | ",
|
| 755 | obj_name, opts.data_sz);
|
| 756 | bpf_object__for_each_map(map, obj) {
|
| 757 | const void *mmap_data = NULL;
|
| 758 | size_t mmap_size = 0;
|
| 759 |
|
| 760 | if (!is_skel_data(map, ident, sizeof(ident)))
|
| 761 | continue;
|
| 762 |
|
| 763 | codegen("\
|
| 764 | \n\
|
| 765 | { \n\
|
| 766 | static const char data[] __attribute__((__aligned__(8))) = \"\\\n\
|
| 767 | ");
|
| 768 | mmap_data = bpf_map__initial_value(map, &mmap_size);
|
| 769 | print_hex(mmap_data, mmap_size);
|
| 770 | codegen("\
|
| 771 | \n\
|
| 772 | \"; \n\
|
| 773 | \n\
|
| 774 | skel->%1$s = (__typeof__(skel->%1$s))skel_prep_map_data((void *)data, %2$zd,\n\
|
| 775 | sizeof(data) - 1);\n\
|
| 776 | if (!skel->%1$s) \n\
|
| 777 | goto cleanup; \n\
|
| 778 | skel->maps.%1$s.initial_value = (__u64) (long) skel->%1$s;\n\
|
| 779 | } \n\
|
| 780 | ", ident, bpf_map_mmap_sz(map));
|
| 781 | }
|
| 782 | codegen("\
|
| 783 | \n\
|
| 784 | return skel; \n\
|
| 785 | cleanup: \n\
|
| 786 | %1$s__destroy(skel); \n\
|
| 787 | return NULL; \n\
|
| 788 | } \n\
|
| 789 | \n\
|
| 790 | static inline int \n\
|
| 791 | %1$s__load(struct %1$s *skel) \n\
|
| 792 | { \n\
|
| 793 | struct bpf_load_and_run_opts opts = {}; \n\
|
| 794 | int err; \n\
|
| 795 | static const char opts_data[] __attribute__((__aligned__(8))) = \"\\\n\
|
| 796 | ",
|
| 797 | obj_name);
|
| 798 | print_hex(opts.data, opts.data_sz);
|
| 799 | codegen("\
|
| 800 | \n\
|
| 801 | \"; \n\
|
| 802 | static const char opts_insn[] __attribute__((__aligned__(8))) = \"\\\n\
|
| 803 | ");
|
| 804 | print_hex(opts.insns, opts.insns_sz);
|
| 805 | codegen("\
|
| 806 | \n\
|
| 807 | \";\n");
|
| 808 |
|
| 809 | if (sign_progs) {
|
| 810 | sopts.insns = opts.insns;
|
| 811 | sopts.insns_sz = opts.insns_sz;
|
| 812 | sopts.data = opts.data;
|
| 813 | sopts.data_sz = opts.data_sz;
|
| 814 | sopts.excl_prog_hash = prog_sha;
|
| 815 | sopts.excl_prog_hash_sz = sizeof(prog_sha);
|
| 816 | sopts.signature = sig_buf;
|
| 817 | sopts.signature_sz = MAX_SIG_SIZE;
|
| 818 |
|
| 819 | err = bpftool_prog_sign(&sopts);
|
| 820 | if (err < 0) {
|
| 821 | p_err("failed to sign program");
|
| 822 | goto out;
|
| 823 | }
|
| 824 |
|
| 825 | codegen("\
|
| 826 | \n\
|
| 827 | static const char opts_sig[] __attribute__((__aligned__(8))) = \"\\\n\
|
| 828 | ");
|
| 829 | print_hex((const void *)sig_buf, sopts.signature_sz);
|
| 830 | codegen("\
|
| 831 | \n\
|
| 832 | \";\n");
|
| 833 |
|
| 834 | codegen("\
|
| 835 | \n\
|
| 836 | static const char opts_excl_hash[] __attribute__((__aligned__(8))) = \"\\\n\
|
| 837 | ");
|
| 838 | print_hex((const void *)prog_sha, sizeof(prog_sha));
|
| 839 | codegen("\
|
| 840 | \n\
|
| 841 | \";\n");
|
| 842 |
|
| 843 | codegen("\
|
| 844 | \n\
|
| 845 | opts.signature = (void *)opts_sig; \n\
|
| 846 | opts.signature_sz = sizeof(opts_sig) - 1; \n\
|
| 847 | opts.excl_prog_hash = (void *)opts_excl_hash; \n\
|
| 848 | opts.excl_prog_hash_sz = sizeof(opts_excl_hash) - 1; \n\
|
| 849 | opts.keyring_id = skel->keyring_id; \n\
|
| 850 | ");
|
| 851 | }
|
| 852 |
|
| 853 | codegen("\
|
| 854 | \n\
|
| 855 | opts.ctx = (struct bpf_loader_ctx *)skel; \n\
|
| 856 | opts.data_sz = sizeof(opts_data) - 1; \n\
|
| 857 | opts.data = (void *)opts_data; \n\
|
| 858 | opts.insns_sz = sizeof(opts_insn) - 1; \n\
|
| 859 | opts.insns = (void *)opts_insn; \n\
|
| 860 | \n\
|
| 861 | err = bpf_load_and_run(&opts); \n\
|
| 862 | if (err < 0) \n\
|
| 863 | return err; \n\
|
| 864 | ");
|
| 865 | bpf_object__for_each_map(map, obj) {
|
| 866 | const char *mmap_flags;
|
| 867 |
|
| 868 | if (!is_skel_data(map, ident, sizeof(ident)))
|
| 869 | continue;
|
| 870 |
|
| 871 | if (bpf_map__type(map) == BPF_MAP_TYPE_PERCPU_ARRAY) {
|
| 872 | codegen("\
|
| 873 | \n\
|
| 874 | err = skel_protect_map_data(skel->%1$s, &skel->maps.%1$s.initial_value, %2$zd);\n\
|
| 875 | if (err) \n\
|
| 876 | return err; \n\
|
| 877 | #ifdef __KERNEL__ \n\
|
| 878 | skel->%1$s = NULL; \n\
|
| 879 | #endif \n\
|
| 880 | ",
|
| 881 | ident, bpf_map_mmap_sz(map));
|
| 882 | continue;
|
| 883 | }
|
| 884 |
|
| 885 | if (bpf_map__map_flags(map) & BPF_F_RDONLY_PROG)
|
| 886 | mmap_flags = "PROT_READ";
|
| 887 | else
|
| 888 | mmap_flags = "PROT_READ | PROT_WRITE";
|
| 889 |
|
| 890 | codegen("\
|
| 891 | \n\
|
| 892 | skel->%1$s = (__typeof__(skel->%1$s))skel_finalize_map_data(&skel->maps.%1$s.initial_value,\n\
|
| 893 | %2$zd, %3$s, skel->maps.%1$s.map_fd);\n\
|
| 894 | if (!skel->%1$s) \n\
|
| 895 | return -ENOMEM; \n\
|
| 896 | ",
|
| 897 | ident, bpf_map_mmap_sz(map), mmap_flags);
|
| 898 | }
|
| 899 | codegen("\
|
| 900 | \n\
|
| 901 | return 0; \n\
|
| 902 | } \n\
|
| 903 | \n\
|
| 904 | static inline struct %1$s * \n\
|
| 905 | %1$s__open_and_load(void) \n\
|
| 906 | { \n\
|
| 907 | struct %1$s *skel; \n\
|
| 908 | \n\
|
| 909 | skel = %1$s__open(); \n\
|
| 910 | if (!skel) \n\
|
| 911 | return NULL; \n\
|
| 912 | if (%1$s__load(skel)) { \n\
|
| 913 | %1$s__destroy(skel); \n\
|
| 914 | return NULL; \n\
|
| 915 | } \n\
|
| 916 | return skel; \n\
|
| 917 | } \n\
|
| 918 | \n\
|
| 919 | ", obj_name);
|
| 920 |
|
| 921 | codegen_asserts(obj, obj_name);
|
| 922 |
|
| 923 | codegen("\
|
| 924 | \n\
|
| 925 | \n\
|
| 926 | #endif /* %s */ \n\
|
| 927 | ",
|
| 928 | header_guard);
|
| 929 | err = 0;
|
| 930 | out:
|
| 931 | return err;
|
| 932 | }
|
| 933 |
|
| 934 | static void
|
| 935 | codegen_maps_skeleton(struct bpf_object *obj, size_t map_cnt, bool mmaped, bool populate_links)
|
| 936 | {
|
| 937 | struct bpf_map *map;
|
| 938 | char ident[256];
|
| 939 | size_t i, map_sz;
|
| 940 |
|
| 941 | if (!map_cnt)
|
| 942 | return;
|
| 943 |
|
| 944 | |
| 945 | * handle new BPF skeleton with new struct bpf_map_skeleton definition
|
| 946 | * that includes link field, avoid specifying new increased size,
|
| 947 | * unless we absolutely have to (i.e., if there are struct_ops maps
|
| 948 | * present)
|
| 949 |
|
| 950 | map_sz = offsetof(struct bpf_map_skeleton, link);
|
| 951 | if (populate_links) {
|
| 952 | bpf_object__for_each_map(map, obj) {
|
| 953 | if (bpf_map__type(map) == BPF_MAP_TYPE_STRUCT_OPS) {
|
| 954 | map_sz = sizeof(struct bpf_map_skeleton);
|
| 955 | break;
|
| 956 | }
|
| 957 | }
|
| 958 | }
|
| 959 |
|
| 960 | codegen("\
|
| 961 | \n\
|
| 962 | \n\
|
| 963 | /* maps */ \n\
|
| 964 | s->map_cnt = %zu; \n\
|
| 965 | s->map_skel_sz = %zu; \n\
|
| 966 | s->maps = (struct bpf_map_skeleton *)calloc(s->map_cnt,\n\
|
| 967 | sizeof(*s->maps) > %zu ? sizeof(*s->maps) : %zu);\n\
|
| 968 | if (!s->maps) { \n\
|
| 969 | err = -ENOMEM; \n\
|
| 970 | goto err; \n\
|
| 971 | } \n\
|
| 972 | ",
|
| 973 | map_cnt, map_sz, map_sz, map_sz
|
| 974 | );
|
| 975 | i = 0;
|
| 976 | bpf_object__for_each_map(map, obj) {
|
| 977 | if (!get_map_ident(map, ident, sizeof(ident)))
|
| 978 | continue;
|
| 979 |
|
| 980 | codegen("\
|
| 981 | \n\
|
| 982 | \n\
|
| 983 | map = (struct bpf_map_skeleton *)((char *)s->maps + %zu * s->map_skel_sz);\n\
|
| 984 | map->name = \"%s\"; \n\
|
| 985 | map->map = &obj->maps.%s; \n\
|
| 986 | ",
|
| 987 | i, bpf_map__name(map), ident);
|
| 988 | if (mmaped && is_skel_data(map, ident, sizeof(ident))) {
|
| 989 | printf("\tmap->mmaped = (void **)&obj->%s;\n", ident);
|
| 990 | }
|
| 991 |
|
| 992 | if (populate_links && bpf_map__type(map) == BPF_MAP_TYPE_STRUCT_OPS) {
|
| 993 | codegen("\
|
| 994 | \n\
|
| 995 | map->link = &obj->links.%s; \n\
|
| 996 | ", ident);
|
| 997 | }
|
| 998 | i++;
|
| 999 | }
|
| 1000 | }
|
| 1001 |
|
| 1002 | static void
|
| 1003 | codegen_progs_skeleton(struct bpf_object *obj, size_t prog_cnt, bool populate_links)
|
| 1004 | {
|
| 1005 | struct bpf_program *prog;
|
| 1006 | int i;
|
| 1007 |
|
| 1008 | if (!prog_cnt)
|
| 1009 | return;
|
| 1010 |
|
| 1011 | codegen("\
|
| 1012 | \n\
|
| 1013 | \n\
|
| 1014 | /* programs */ \n\
|
| 1015 | s->prog_cnt = %zu; \n\
|
| 1016 | s->prog_skel_sz = sizeof(*s->progs); \n\
|
| 1017 | s->progs = (struct bpf_prog_skeleton *)calloc(s->prog_cnt, s->prog_skel_sz);\n\
|
| 1018 | if (!s->progs) { \n\
|
| 1019 | err = -ENOMEM; \n\
|
| 1020 | goto err; \n\
|
| 1021 | } \n\
|
| 1022 | ",
|
| 1023 | prog_cnt
|
| 1024 | );
|
| 1025 | i = 0;
|
| 1026 | bpf_object__for_each_program(prog, obj) {
|
| 1027 | codegen("\
|
| 1028 | \n\
|
| 1029 | \n\
|
| 1030 | s->progs[%1$zu].name = \"%2$s\"; \n\
|
| 1031 | s->progs[%1$zu].prog = &obj->progs.%2$s;\n\
|
| 1032 | ",
|
| 1033 | i, bpf_program__name(prog));
|
| 1034 |
|
| 1035 | if (populate_links) {
|
| 1036 | codegen("\
|
| 1037 | \n\
|
| 1038 | s->progs[%1$zu].link = &obj->links.%2$s;\n\
|
| 1039 | ",
|
| 1040 | i, bpf_program__name(prog));
|
| 1041 | }
|
| 1042 | i++;
|
| 1043 | }
|
| 1044 | }
|
| 1045 |
|
| 1046 | static int walk_st_ops_shadow_vars(struct btf *btf, const char *ident,
|
| 1047 | const struct btf_type *map_type, __u32 map_type_id)
|
| 1048 | {
|
| 1049 | LIBBPF_OPTS(btf_dump_emit_type_decl_opts, opts, .indent_level = 3);
|
| 1050 | const struct btf_type *member_type;
|
| 1051 | __u32 offset, next_offset = 0;
|
| 1052 | const struct btf_member *m;
|
| 1053 | struct btf_dump *d = NULL;
|
| 1054 | const char *member_name;
|
| 1055 | __u32 member_type_id;
|
| 1056 | int i, err = 0, n;
|
| 1057 | int size;
|
| 1058 |
|
| 1059 | d = btf_dump__new(btf, codegen_btf_dump_printf, NULL, NULL);
|
| 1060 | if (!d)
|
| 1061 | return -errno;
|
| 1062 |
|
| 1063 | n = btf_vlen(map_type);
|
| 1064 | for (i = 0, m = btf_members(map_type); i < n; i++, m++) {
|
| 1065 | member_type = skip_mods_and_typedefs(btf, m->type, &member_type_id);
|
| 1066 | member_name = btf__name_by_offset(btf, m->name_off);
|
| 1067 |
|
| 1068 | offset = m->offset / 8;
|
| 1069 | if (next_offset < offset)
|
| 1070 | printf("\t\t\tchar __padding_%d[%u];\n", i, offset - next_offset);
|
| 1071 |
|
| 1072 | switch (btf_kind(member_type)) {
|
| 1073 | case BTF_KIND_INT:
|
| 1074 | case BTF_KIND_FLOAT:
|
| 1075 | case BTF_KIND_ENUM:
|
| 1076 | case BTF_KIND_ENUM64:
|
| 1077 |
|
| 1078 | printf("\t\t\t");
|
| 1079 | opts.field_name = member_name;
|
| 1080 | err = btf_dump__emit_type_decl(d, member_type_id, &opts);
|
| 1081 | if (err) {
|
| 1082 | p_err("Failed to emit type declaration for %s: %d", member_name, err);
|
| 1083 | goto out;
|
| 1084 | }
|
| 1085 | printf(";\n");
|
| 1086 |
|
| 1087 | size = btf__resolve_size(btf, member_type_id);
|
| 1088 | if (size < 0) {
|
| 1089 | p_err("Failed to resolve size of %s: %d\n", member_name, size);
|
| 1090 | err = size;
|
| 1091 | goto out;
|
| 1092 | }
|
| 1093 |
|
| 1094 | next_offset = offset + size;
|
| 1095 | break;
|
| 1096 |
|
| 1097 | case BTF_KIND_PTR:
|
| 1098 | if (resolve_func_ptr(btf, m->type, NULL)) {
|
| 1099 |
|
| 1100 | printf("\t\t\tstruct bpf_program *%s;\n", member_name);
|
| 1101 |
|
| 1102 | next_offset = offset + sizeof(void *);
|
| 1103 | break;
|
| 1104 | }
|
| 1105 | |
| 1106 | * function pointers.
|
| 1107 |
|
| 1108 | fallthrough;
|
| 1109 |
|
| 1110 | default:
|
| 1111 | |
| 1112 | *
|
| 1113 | * Types other than scalar types and function
|
| 1114 | * pointers are currently not supported in order to
|
| 1115 | * prevent conflicts in the generated code caused
|
| 1116 | * by multiple definitions. For instance, if the
|
| 1117 | * struct type FOO is used in a struct_ops map,
|
| 1118 | * bpftool has to generate definitions for FOO,
|
| 1119 | * which may result in conflicts if FOO is defined
|
| 1120 | * in different skeleton files.
|
| 1121 |
|
| 1122 | size = btf__resolve_size(btf, member_type_id);
|
| 1123 | if (size < 0) {
|
| 1124 | p_err("Failed to resolve size of %s: %d\n", member_name, size);
|
| 1125 | err = size;
|
| 1126 | goto out;
|
| 1127 | }
|
| 1128 | printf("\t\t\tchar __unsupported_%d[%d];\n", i, size);
|
| 1129 |
|
| 1130 | next_offset = offset + size;
|
| 1131 | break;
|
| 1132 | }
|
| 1133 | }
|
| 1134 |
|
| 1135 |
|
| 1136 | size = btf__resolve_size(btf, map_type_id);
|
| 1137 | if (next_offset < (__u32)size)
|
| 1138 | printf("\t\t\tchar __padding_end[%u];\n", size - next_offset);
|
| 1139 |
|
| 1140 | out:
|
| 1141 | btf_dump__free(d);
|
| 1142 |
|
| 1143 | return err;
|
| 1144 | }
|
| 1145 |
|
| 1146 | |
| 1147 | *
|
| 1148 | * This function adds a pointer of the shadow type for a struct_ops map.
|
| 1149 | * The members of a struct_ops map can be exported through a pointer to a
|
| 1150 | * shadow type. The user can access these members through the pointer.
|
| 1151 | *
|
| 1152 | * A shadow type includes not all members, only members of some types.
|
| 1153 | * They are scalar types and function pointers. The function pointers are
|
| 1154 | * translated to the pointer of the struct bpf_program. The scalar types
|
| 1155 | * are translated to the original type without any modifiers.
|
| 1156 | *
|
| 1157 | * Unsupported types will be translated to a char array to occupy the same
|
| 1158 | * space as the original field, being renamed as __unsupported_*. The user
|
| 1159 | * should treat these fields as opaque data.
|
| 1160 |
|
| 1161 | static int gen_st_ops_shadow_type(const char *obj_name, struct btf *btf, const char *ident,
|
| 1162 | const struct bpf_map *map)
|
| 1163 | {
|
| 1164 | const struct btf_type *map_type;
|
| 1165 | const char *type_name;
|
| 1166 | __u32 map_type_id;
|
| 1167 | int err;
|
| 1168 |
|
| 1169 | map_type_id = bpf_map__btf_value_type_id(map);
|
| 1170 | if (map_type_id == 0)
|
| 1171 | return -EINVAL;
|
| 1172 | map_type = btf__type_by_id(btf, map_type_id);
|
| 1173 | if (!map_type)
|
| 1174 | return -EINVAL;
|
| 1175 |
|
| 1176 | type_name = btf__name_by_offset(btf, map_type->name_off);
|
| 1177 |
|
| 1178 | printf("\t\tstruct %s__%s__%s {\n", obj_name, ident, type_name);
|
| 1179 |
|
| 1180 | err = walk_st_ops_shadow_vars(btf, ident, map_type, map_type_id);
|
| 1181 | if (err)
|
| 1182 | return err;
|
| 1183 |
|
| 1184 | printf("\t\t} *%s;\n", ident);
|
| 1185 |
|
| 1186 | return 0;
|
| 1187 | }
|
| 1188 |
|
| 1189 | static int gen_st_ops_shadow(const char *obj_name, struct btf *btf, struct bpf_object *obj)
|
| 1190 | {
|
| 1191 | int err, st_ops_cnt = 0;
|
| 1192 | struct bpf_map *map;
|
| 1193 | char ident[256];
|
| 1194 |
|
| 1195 | if (!btf)
|
| 1196 | return 0;
|
| 1197 |
|
| 1198 | |
| 1199 | * struct_ops maps.
|
| 1200 |
|
| 1201 | bpf_object__for_each_map(map, obj) {
|
| 1202 | if (bpf_map__type(map) != BPF_MAP_TYPE_STRUCT_OPS)
|
| 1203 | continue;
|
| 1204 | if (!get_map_ident(map, ident, sizeof(ident)))
|
| 1205 | continue;
|
| 1206 |
|
| 1207 | if (st_ops_cnt == 0)
|
| 1208 | printf("\tstruct {\n");
|
| 1209 | st_ops_cnt++;
|
| 1210 |
|
| 1211 | err = gen_st_ops_shadow_type(obj_name, btf, ident, map);
|
| 1212 | if (err)
|
| 1213 | return err;
|
| 1214 | }
|
| 1215 |
|
| 1216 | if (st_ops_cnt)
|
| 1217 | printf("\t} struct_ops;\n");
|
| 1218 |
|
| 1219 | return 0;
|
| 1220 | }
|
| 1221 |
|
| 1222 |
|
| 1223 | static void gen_st_ops_shadow_init(struct btf *btf, struct bpf_object *obj)
|
| 1224 | {
|
| 1225 | struct bpf_map *map;
|
| 1226 | char ident[256];
|
| 1227 |
|
| 1228 | if (!btf)
|
| 1229 | return;
|
| 1230 |
|
| 1231 | |
| 1232 | * struct_ops maps.
|
| 1233 |
|
| 1234 | bpf_object__for_each_map(map, obj) {
|
| 1235 | if (bpf_map__type(map) != BPF_MAP_TYPE_STRUCT_OPS)
|
| 1236 | continue;
|
| 1237 | if (!get_map_ident(map, ident, sizeof(ident)))
|
| 1238 | continue;
|
| 1239 | codegen("\
|
| 1240 | \n\
|
| 1241 | obj->struct_ops.%1$s = (__typeof__(obj->struct_ops.%1$s))\n\
|
| 1242 | bpf_map__initial_value(obj->maps.%1$s, NULL);\n\
|
| 1243 | \n\
|
| 1244 | ", ident);
|
| 1245 | }
|
| 1246 | }
|
| 1247 |
|
| 1248 | static int do_skeleton(int argc, char **argv)
|
| 1249 | {
|
| 1250 | char header_guard[MAX_OBJ_NAME_LEN + sizeof("__SKEL_H__")];
|
| 1251 | size_t map_cnt = 0, prog_cnt = 0, attach_map_cnt = 0, file_sz, mmap_sz;
|
| 1252 | DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts);
|
| 1253 | char obj_name[MAX_OBJ_NAME_LEN] = "", *obj_data;
|
| 1254 | struct bpf_object *obj = NULL;
|
| 1255 | const char *file;
|
| 1256 | char ident[256];
|
| 1257 | struct bpf_program *prog;
|
| 1258 | int fd, err = -1;
|
| 1259 | struct bpf_map *map;
|
| 1260 | struct btf *btf;
|
| 1261 | struct stat st;
|
| 1262 |
|
| 1263 | if (!REQ_ARGS(1)) {
|
| 1264 | usage();
|
| 1265 | return -1;
|
| 1266 | }
|
| 1267 | file = GET_ARG();
|
| 1268 |
|
| 1269 | while (argc) {
|
| 1270 | if (!REQ_ARGS(2))
|
| 1271 | return -1;
|
| 1272 |
|
| 1273 | if (is_prefix(*argv, "name")) {
|
| 1274 | NEXT_ARG();
|
| 1275 |
|
| 1276 | if (obj_name[0] != '\0') {
|
| 1277 | p_err("object name already specified");
|
| 1278 | return -1;
|
| 1279 | }
|
| 1280 |
|
| 1281 | strncpy(obj_name, *argv, MAX_OBJ_NAME_LEN - 1);
|
| 1282 | obj_name[MAX_OBJ_NAME_LEN - 1] = '\0';
|
| 1283 | } else {
|
| 1284 | p_err("unknown arg %s", *argv);
|
| 1285 | return -1;
|
| 1286 | }
|
| 1287 |
|
| 1288 | NEXT_ARG();
|
| 1289 | }
|
| 1290 |
|
| 1291 | if (argc) {
|
| 1292 | p_err("extra unknown arguments");
|
| 1293 | return -1;
|
| 1294 | }
|
| 1295 |
|
| 1296 | if (stat(file, &st)) {
|
| 1297 | p_err("failed to stat() %s: %s", file, strerror(errno));
|
| 1298 | return -1;
|
| 1299 | }
|
| 1300 | file_sz = st.st_size;
|
| 1301 | mmap_sz = roundup(file_sz, sysconf(_SC_PAGE_SIZE));
|
| 1302 | fd = open(file, O_RDONLY);
|
| 1303 | if (fd < 0) {
|
| 1304 | p_err("failed to open() %s: %s", file, strerror(errno));
|
| 1305 | return -1;
|
| 1306 | }
|
| 1307 | obj_data = mmap(NULL, mmap_sz, PROT_READ, MAP_PRIVATE, fd, 0);
|
| 1308 | if (obj_data == MAP_FAILED) {
|
| 1309 | obj_data = NULL;
|
| 1310 | p_err("failed to mmap() %s: %s", file, strerror(errno));
|
| 1311 | goto out;
|
| 1312 | }
|
| 1313 | if (obj_name[0] == '\0')
|
| 1314 | get_obj_name(obj_name, file);
|
| 1315 | opts.object_name = obj_name;
|
| 1316 | if (verifier_logs)
|
| 1317 |
|
| 1318 | opts.kernel_log_level = 1 + 2 + 4;
|
| 1319 | obj = bpf_object__open_mem(obj_data, file_sz, &opts);
|
| 1320 | if (!obj) {
|
| 1321 | char err_buf[256];
|
| 1322 |
|
| 1323 | err = -errno;
|
| 1324 | libbpf_strerror(err, err_buf, sizeof(err_buf));
|
| 1325 | p_err("failed to open BPF object file: %s", err_buf);
|
| 1326 | goto out_obj;
|
| 1327 | }
|
| 1328 |
|
| 1329 | bpf_object__for_each_map(map, obj) {
|
| 1330 | if (!get_map_ident(map, ident, sizeof(ident))) {
|
| 1331 | p_err("ignoring unrecognized internal map '%s'...",
|
| 1332 | bpf_map__name(map));
|
| 1333 | continue;
|
| 1334 | }
|
| 1335 |
|
| 1336 | if (bpf_map__type(map) == BPF_MAP_TYPE_STRUCT_OPS)
|
| 1337 | attach_map_cnt++;
|
| 1338 |
|
| 1339 | map_cnt++;
|
| 1340 | }
|
| 1341 | bpf_object__for_each_program(prog, obj) {
|
| 1342 | prog_cnt++;
|
| 1343 | }
|
| 1344 |
|
| 1345 | get_header_guard(header_guard, obj_name, "SKEL_H");
|
| 1346 | if (use_loader) {
|
| 1347 | codegen("\
|
| 1348 | \n\
|
| 1349 | /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ \n\
|
| 1350 | /* THIS FILE IS AUTOGENERATED BY BPFTOOL! */ \n\
|
| 1351 | #ifndef %2$s \n\
|
| 1352 | #define %2$s \n\
|
| 1353 | \n\
|
| 1354 | #include <bpf/skel_internal.h> \n\
|
| 1355 | \n\
|
| 1356 | struct %1$s { \n\
|
| 1357 | struct bpf_loader_ctx ctx; \n\
|
| 1358 | ",
|
| 1359 | obj_name, header_guard
|
| 1360 | );
|
| 1361 | } else {
|
| 1362 | codegen("\
|
| 1363 | \n\
|
| 1364 | /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ \n\
|
| 1365 | \n\
|
| 1366 | /* THIS FILE IS AUTOGENERATED BY BPFTOOL! */ \n\
|
| 1367 | #ifndef %2$s \n\
|
| 1368 | #define %2$s \n\
|
| 1369 | \n\
|
| 1370 | #include <errno.h> \n\
|
| 1371 | #include <stdlib.h> \n\
|
| 1372 | #include <bpf/libbpf.h> \n\
|
| 1373 | \n\
|
| 1374 | #define BPF_SKEL_SUPPORTS_MAP_AUTO_ATTACH 1 \n\
|
| 1375 | \n\
|
| 1376 | struct %1$s { \n\
|
| 1377 | struct bpf_object_skeleton *skeleton; \n\
|
| 1378 | struct bpf_object *obj; \n\
|
| 1379 | ",
|
| 1380 | obj_name, header_guard
|
| 1381 | );
|
| 1382 | }
|
| 1383 |
|
| 1384 | if (map_cnt) {
|
| 1385 | printf("\tstruct {\n");
|
| 1386 | bpf_object__for_each_map(map, obj) {
|
| 1387 | if (!get_map_ident(map, ident, sizeof(ident)))
|
| 1388 | continue;
|
| 1389 | if (use_loader)
|
| 1390 | printf("\t\tstruct bpf_map_desc %s;\n", ident);
|
| 1391 | else
|
| 1392 | printf("\t\tstruct bpf_map *%s;\n", ident);
|
| 1393 | }
|
| 1394 | printf("\t} maps;\n");
|
| 1395 | }
|
| 1396 |
|
| 1397 | btf = bpf_object__btf(obj);
|
| 1398 | err = gen_st_ops_shadow(obj_name, btf, obj);
|
| 1399 | if (err)
|
| 1400 | goto out;
|
| 1401 |
|
| 1402 | if (prog_cnt) {
|
| 1403 | printf("\tstruct {\n");
|
| 1404 | bpf_object__for_each_program(prog, obj) {
|
| 1405 | if (use_loader)
|
| 1406 | printf("\t\tstruct bpf_prog_desc %s;\n",
|
| 1407 | bpf_program__name(prog));
|
| 1408 | else
|
| 1409 | printf("\t\tstruct bpf_program *%s;\n",
|
| 1410 | bpf_program__name(prog));
|
| 1411 | }
|
| 1412 | printf("\t} progs;\n");
|
| 1413 | }
|
| 1414 |
|
| 1415 | if (prog_cnt + attach_map_cnt) {
|
| 1416 | printf("\tstruct {\n");
|
| 1417 | bpf_object__for_each_program(prog, obj) {
|
| 1418 | if (use_loader)
|
| 1419 | printf("\t\tint %s_fd;\n",
|
| 1420 | bpf_program__name(prog));
|
| 1421 | else
|
| 1422 | printf("\t\tstruct bpf_link *%s;\n",
|
| 1423 | bpf_program__name(prog));
|
| 1424 | }
|
| 1425 |
|
| 1426 | bpf_object__for_each_map(map, obj) {
|
| 1427 | if (!get_map_ident(map, ident, sizeof(ident)))
|
| 1428 | continue;
|
| 1429 | if (bpf_map__type(map) != BPF_MAP_TYPE_STRUCT_OPS)
|
| 1430 | continue;
|
| 1431 |
|
| 1432 | if (use_loader)
|
| 1433 | printf("\t\tint %s_fd;\n", ident);
|
| 1434 | else
|
| 1435 | printf("\t\tstruct bpf_link *%s;\n", ident);
|
| 1436 | }
|
| 1437 |
|
| 1438 | printf("\t} links;\n");
|
| 1439 | }
|
| 1440 |
|
| 1441 | if (sign_progs) {
|
| 1442 | codegen("\
|
| 1443 | \n\
|
| 1444 | __s32 keyring_id; \n\
|
| 1445 | ");
|
| 1446 | }
|
| 1447 |
|
| 1448 | if (btf) {
|
| 1449 | err = codegen_datasecs(obj, obj_name);
|
| 1450 | if (err)
|
| 1451 | goto out;
|
| 1452 | }
|
| 1453 | if (use_loader) {
|
| 1454 | err = gen_trace(obj, obj_name, header_guard);
|
| 1455 | goto out;
|
| 1456 | }
|
| 1457 |
|
| 1458 | codegen("\
|
| 1459 | \n\
|
| 1460 | \n\
|
| 1461 | #ifdef __cplusplus \n\
|
| 1462 | static inline struct %1$s *open(const struct bpf_object_open_opts *opts = nullptr);\n\
|
| 1463 | static inline struct %1$s *open_and_load(); \n\
|
| 1464 | static inline int load(struct %1$s *skel); \n\
|
| 1465 | static inline int attach(struct %1$s *skel); \n\
|
| 1466 | static inline void detach(struct %1$s *skel); \n\
|
| 1467 | static inline void destroy(struct %1$s *skel); \n\
|
| 1468 | static inline const void *elf_bytes(size_t *sz); \n\
|
| 1469 | #endif /* __cplusplus */ \n\
|
| 1470 | }; \n\
|
| 1471 | \n\
|
| 1472 | static void \n\
|
| 1473 | %1$s__destroy(struct %1$s *obj) \n\
|
| 1474 | { \n\
|
| 1475 | if (!obj) \n\
|
| 1476 | return; \n\
|
| 1477 | if (obj->skeleton) \n\
|
| 1478 | bpf_object__destroy_skeleton(obj->skeleton);\n\
|
| 1479 | free(obj); \n\
|
| 1480 | } \n\
|
| 1481 | \n\
|
| 1482 | static inline int \n\
|
| 1483 | %1$s__create_skeleton(struct %1$s *obj); \n\
|
| 1484 | \n\
|
| 1485 | static inline struct %1$s * \n\
|
| 1486 | %1$s__open_opts(const struct bpf_object_open_opts *opts) \n\
|
| 1487 | { \n\
|
| 1488 | struct %1$s *obj; \n\
|
| 1489 | int err; \n\
|
| 1490 | \n\
|
| 1491 | obj = (struct %1$s *)calloc(1, sizeof(*obj)); \n\
|
| 1492 | if (!obj) { \n\
|
| 1493 | errno = ENOMEM; \n\
|
| 1494 | return NULL; \n\
|
| 1495 | } \n\
|
| 1496 | \n\
|
| 1497 | err = %1$s__create_skeleton(obj); \n\
|
| 1498 | if (err) \n\
|
| 1499 | goto err_out; \n\
|
| 1500 | \n\
|
| 1501 | err = bpf_object__open_skeleton(obj->skeleton, opts);\n\
|
| 1502 | if (err) \n\
|
| 1503 | goto err_out; \n\
|
| 1504 | \n\
|
| 1505 | ", obj_name);
|
| 1506 |
|
| 1507 | gen_st_ops_shadow_init(btf, obj);
|
| 1508 |
|
| 1509 | codegen("\
|
| 1510 | \n\
|
| 1511 | return obj; \n\
|
| 1512 | err_out: \n\
|
| 1513 | %1$s__destroy(obj); \n\
|
| 1514 | errno = -err; \n\
|
| 1515 | return NULL; \n\
|
| 1516 | } \n\
|
| 1517 | \n\
|
| 1518 | static inline struct %1$s * \n\
|
| 1519 | %1$s__open(void) \n\
|
| 1520 | { \n\
|
| 1521 | return %1$s__open_opts(NULL); \n\
|
| 1522 | } \n\
|
| 1523 | \n\
|
| 1524 | static inline int \n\
|
| 1525 | %1$s__load(struct %1$s *obj) \n\
|
| 1526 | { \n\
|
| 1527 | return bpf_object__load_skeleton(obj->skeleton); \n\
|
| 1528 | } \n\
|
| 1529 | \n\
|
| 1530 | static inline struct %1$s * \n\
|
| 1531 | %1$s__open_and_load(void) \n\
|
| 1532 | { \n\
|
| 1533 | struct %1$s *obj; \n\
|
| 1534 | int err; \n\
|
| 1535 | \n\
|
| 1536 | obj = %1$s__open(); \n\
|
| 1537 | if (!obj) \n\
|
| 1538 | return NULL; \n\
|
| 1539 | err = %1$s__load(obj); \n\
|
| 1540 | if (err) { \n\
|
| 1541 | %1$s__destroy(obj); \n\
|
| 1542 | errno = -err; \n\
|
| 1543 | return NULL; \n\
|
| 1544 | } \n\
|
| 1545 | return obj; \n\
|
| 1546 | } \n\
|
| 1547 | \n\
|
| 1548 | static inline int \n\
|
| 1549 | %1$s__attach(struct %1$s *obj) \n\
|
| 1550 | { \n\
|
| 1551 | return bpf_object__attach_skeleton(obj->skeleton); \n\
|
| 1552 | } \n\
|
| 1553 | \n\
|
| 1554 | static inline void \n\
|
| 1555 | %1$s__detach(struct %1$s *obj) \n\
|
| 1556 | { \n\
|
| 1557 | bpf_object__detach_skeleton(obj->skeleton); \n\
|
| 1558 | } \n\
|
| 1559 | ",
|
| 1560 | obj_name
|
| 1561 | );
|
| 1562 |
|
| 1563 | codegen("\
|
| 1564 | \n\
|
| 1565 | \n\
|
| 1566 | static inline const void *%1$s__elf_bytes(size_t *sz); \n\
|
| 1567 | \n\
|
| 1568 | static inline int \n\
|
| 1569 | %1$s__create_skeleton(struct %1$s *obj) \n\
|
| 1570 | { \n\
|
| 1571 | struct bpf_object_skeleton *s; \n\
|
| 1572 | struct bpf_map_skeleton *map __attribute__((unused));\n\
|
| 1573 | int err; \n\
|
| 1574 | \n\
|
| 1575 | s = (struct bpf_object_skeleton *)calloc(1, sizeof(*s));\n\
|
| 1576 | if (!s) { \n\
|
| 1577 | err = -ENOMEM; \n\
|
| 1578 | goto err; \n\
|
| 1579 | } \n\
|
| 1580 | \n\
|
| 1581 | s->sz = sizeof(*s); \n\
|
| 1582 | s->name = \"%1$s\"; \n\
|
| 1583 | s->obj = &obj->obj; \n\
|
| 1584 | ",
|
| 1585 | obj_name
|
| 1586 | );
|
| 1587 |
|
| 1588 | codegen_maps_skeleton(obj, map_cnt, true , true );
|
| 1589 | codegen_progs_skeleton(obj, prog_cnt, true );
|
| 1590 |
|
| 1591 | codegen("\
|
| 1592 | \n\
|
| 1593 | \n\
|
| 1594 | s->data = %1$s__elf_bytes(&s->data_sz); \n\
|
| 1595 | \n\
|
| 1596 | obj->skeleton = s; \n\
|
| 1597 | return 0; \n\
|
| 1598 | err: \n\
|
| 1599 | bpf_object__destroy_skeleton(s); \n\
|
| 1600 | return err; \n\
|
| 1601 | } \n\
|
| 1602 | \n\
|
| 1603 | static inline const void *%1$s__elf_bytes(size_t *sz) \n\
|
| 1604 | { \n\
|
| 1605 | static const char data[] __attribute__((__aligned__(8))) = \"\\\n\
|
| 1606 | ",
|
| 1607 | obj_name
|
| 1608 | );
|
| 1609 |
|
| 1610 |
|
| 1611 | print_hex(obj_data, file_sz);
|
| 1612 |
|
| 1613 | codegen("\
|
| 1614 | \n\
|
| 1615 | \"; \n\
|
| 1616 | \n\
|
| 1617 | *sz = sizeof(data) - 1; \n\
|
| 1618 | return (const void *)data; \n\
|
| 1619 | } \n\
|
| 1620 | \n\
|
| 1621 | #ifdef __cplusplus \n\
|
| 1622 | struct %1$s *%1$s::open(const struct bpf_object_open_opts *opts) { return %1$s__open_opts(opts); }\n\
|
| 1623 | struct %1$s *%1$s::open_and_load() { return %1$s__open_and_load(); } \n\
|
| 1624 | int %1$s::load(struct %1$s *skel) { return %1$s__load(skel); } \n\
|
| 1625 | int %1$s::attach(struct %1$s *skel) { return %1$s__attach(skel); } \n\
|
| 1626 | void %1$s::detach(struct %1$s *skel) { %1$s__detach(skel); } \n\
|
| 1627 | void %1$s::destroy(struct %1$s *skel) { %1$s__destroy(skel); } \n\
|
| 1628 | const void *%1$s::elf_bytes(size_t *sz) { return %1$s__elf_bytes(sz); } \n\
|
| 1629 | #endif /* __cplusplus */ \n\
|
| 1630 | \n\
|
| 1631 | ",
|
| 1632 | obj_name);
|
| 1633 |
|
| 1634 | codegen_asserts(obj, obj_name);
|
| 1635 |
|
| 1636 | codegen("\
|
| 1637 | \n\
|
| 1638 | \n\
|
| 1639 | #endif /* %1$s */ \n\
|
| 1640 | ",
|
| 1641 | header_guard);
|
| 1642 | err = 0;
|
| 1643 | out:
|
| 1644 | bpf_object__close(obj);
|
| 1645 | out_obj:
|
| 1646 | if (obj_data)
|
| 1647 | munmap(obj_data, mmap_sz);
|
| 1648 | close(fd);
|
| 1649 | return err;
|
| 1650 | }
|
| 1651 |
|
| 1652 | |
| 1653 | * associated maps, links, etc. Instead, they know about the existence of
|
| 1654 | * variables, maps, programs and are able to find their locations
|
| 1655 | * _at runtime_ from an already loaded bpf_object.
|
| 1656 | *
|
| 1657 | * This allows for library-like BPF objects to have userspace counterparts
|
| 1658 | * with access to their own items without having to know anything about the
|
| 1659 | * final BPF object that the library was linked into.
|
| 1660 |
|
| 1661 | static int do_subskeleton(int argc, char **argv)
|
| 1662 | {
|
| 1663 | char header_guard[MAX_OBJ_NAME_LEN + sizeof("__SUBSKEL_H__")];
|
| 1664 | size_t i, len, file_sz, map_cnt = 0, prog_cnt = 0, mmap_sz, var_cnt = 0, var_idx = 0;
|
| 1665 | DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts);
|
| 1666 | char obj_name[MAX_OBJ_NAME_LEN] = "", *obj_data;
|
| 1667 | struct bpf_object *obj = NULL;
|
| 1668 | const char *file, *var_name;
|
| 1669 | char ident[256];
|
| 1670 | int fd, err = -1, map_type_id;
|
| 1671 | const struct bpf_map *map;
|
| 1672 | struct bpf_program *prog;
|
| 1673 | struct btf *btf;
|
| 1674 | const struct btf_type *map_type, *var_type;
|
| 1675 | const struct btf_var_secinfo *var;
|
| 1676 | struct stat st;
|
| 1677 |
|
| 1678 | if (!REQ_ARGS(1)) {
|
| 1679 | usage();
|
| 1680 | return -1;
|
| 1681 | }
|
| 1682 | file = GET_ARG();
|
| 1683 |
|
| 1684 | while (argc) {
|
| 1685 | if (!REQ_ARGS(2))
|
| 1686 | return -1;
|
| 1687 |
|
| 1688 | if (is_prefix(*argv, "name")) {
|
| 1689 | NEXT_ARG();
|
| 1690 |
|
| 1691 | if (obj_name[0] != '\0') {
|
| 1692 | p_err("object name already specified");
|
| 1693 | return -1;
|
| 1694 | }
|
| 1695 |
|
| 1696 | strncpy(obj_name, *argv, MAX_OBJ_NAME_LEN - 1);
|
| 1697 | obj_name[MAX_OBJ_NAME_LEN - 1] = '\0';
|
| 1698 | } else {
|
| 1699 | p_err("unknown arg %s", *argv);
|
| 1700 | return -1;
|
| 1701 | }
|
| 1702 |
|
| 1703 | NEXT_ARG();
|
| 1704 | }
|
| 1705 |
|
| 1706 | if (argc) {
|
| 1707 | p_err("extra unknown arguments");
|
| 1708 | return -1;
|
| 1709 | }
|
| 1710 |
|
| 1711 | if (use_loader) {
|
| 1712 | p_err("cannot use loader for subskeletons");
|
| 1713 | return -1;
|
| 1714 | }
|
| 1715 |
|
| 1716 | if (stat(file, &st)) {
|
| 1717 | p_err("failed to stat() %s: %s", file, strerror(errno));
|
| 1718 | return -1;
|
| 1719 | }
|
| 1720 | file_sz = st.st_size;
|
| 1721 | mmap_sz = roundup(file_sz, sysconf(_SC_PAGE_SIZE));
|
| 1722 | fd = open(file, O_RDONLY);
|
| 1723 | if (fd < 0) {
|
| 1724 | p_err("failed to open() %s: %s", file, strerror(errno));
|
| 1725 | return -1;
|
| 1726 | }
|
| 1727 | obj_data = mmap(NULL, mmap_sz, PROT_READ, MAP_PRIVATE, fd, 0);
|
| 1728 | if (obj_data == MAP_FAILED) {
|
| 1729 | obj_data = NULL;
|
| 1730 | p_err("failed to mmap() %s: %s", file, strerror(errno));
|
| 1731 | goto out;
|
| 1732 | }
|
| 1733 | if (obj_name[0] == '\0')
|
| 1734 | get_obj_name(obj_name, file);
|
| 1735 |
|
| 1736 | |
| 1737 | * ELF section names out of it. (".data" instead of "obj.data")
|
| 1738 |
|
| 1739 | opts.object_name = "";
|
| 1740 | obj = bpf_object__open_mem(obj_data, file_sz, &opts);
|
| 1741 | if (!obj) {
|
| 1742 | char err_buf[256];
|
| 1743 |
|
| 1744 | libbpf_strerror(errno, err_buf, sizeof(err_buf));
|
| 1745 | p_err("failed to open BPF object file: %s", err_buf);
|
| 1746 | obj = NULL;
|
| 1747 | goto out;
|
| 1748 | }
|
| 1749 |
|
| 1750 | btf = bpf_object__btf(obj);
|
| 1751 | if (!btf) {
|
| 1752 | err = -1;
|
| 1753 | p_err("need btf type information for %s", obj_name);
|
| 1754 | goto out;
|
| 1755 | }
|
| 1756 |
|
| 1757 | bpf_object__for_each_program(prog, obj) {
|
| 1758 | prog_cnt++;
|
| 1759 | }
|
| 1760 |
|
| 1761 | |
| 1762 | * We need this in advance so the subskel can allocate the right
|
| 1763 | * amount of storage.
|
| 1764 |
|
| 1765 | bpf_object__for_each_map(map, obj) {
|
| 1766 | if (!get_map_ident(map, ident, sizeof(ident)))
|
| 1767 | continue;
|
| 1768 |
|
| 1769 |
|
| 1770 | map_cnt++;
|
| 1771 |
|
| 1772 | if (!is_mmapable_map(map, ident, sizeof(ident)))
|
| 1773 | continue;
|
| 1774 |
|
| 1775 | map_type_id = bpf_map__btf_value_type_id(map);
|
| 1776 | if (map_type_id <= 0) {
|
| 1777 | err = map_type_id;
|
| 1778 | goto out;
|
| 1779 | }
|
| 1780 | map_type = btf__type_by_id(btf, map_type_id);
|
| 1781 |
|
| 1782 | var = btf_var_secinfos(map_type);
|
| 1783 | len = btf_vlen(map_type);
|
| 1784 | for (i = 0; i < len; i++, var++) {
|
| 1785 | var_type = btf__type_by_id(btf, var->type);
|
| 1786 |
|
| 1787 | if (btf_var(var_type)->linkage == BTF_VAR_STATIC)
|
| 1788 | continue;
|
| 1789 |
|
| 1790 | var_cnt++;
|
| 1791 | }
|
| 1792 | }
|
| 1793 |
|
| 1794 | get_header_guard(header_guard, obj_name, "SUBSKEL_H");
|
| 1795 | codegen("\
|
| 1796 | \n\
|
| 1797 | /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */ \n\
|
| 1798 | \n\
|
| 1799 | /* THIS FILE IS AUTOGENERATED! */ \n\
|
| 1800 | #ifndef %2$s \n\
|
| 1801 | #define %2$s \n\
|
| 1802 | \n\
|
| 1803 | #include <errno.h> \n\
|
| 1804 | #include <stdlib.h> \n\
|
| 1805 | #include <bpf/libbpf.h> \n\
|
| 1806 | \n\
|
| 1807 | struct %1$s { \n\
|
| 1808 | struct bpf_object *obj; \n\
|
| 1809 | struct bpf_object_subskeleton *subskel; \n\
|
| 1810 | ", obj_name, header_guard);
|
| 1811 |
|
| 1812 | if (map_cnt) {
|
| 1813 | printf("\tstruct {\n");
|
| 1814 | bpf_object__for_each_map(map, obj) {
|
| 1815 | if (!get_map_ident(map, ident, sizeof(ident)))
|
| 1816 | continue;
|
| 1817 | printf("\t\tstruct bpf_map *%s;\n", ident);
|
| 1818 | }
|
| 1819 | printf("\t} maps;\n");
|
| 1820 | }
|
| 1821 |
|
| 1822 | err = gen_st_ops_shadow(obj_name, btf, obj);
|
| 1823 | if (err)
|
| 1824 | goto out;
|
| 1825 |
|
| 1826 | if (prog_cnt) {
|
| 1827 | printf("\tstruct {\n");
|
| 1828 | bpf_object__for_each_program(prog, obj) {
|
| 1829 | printf("\t\tstruct bpf_program *%s;\n",
|
| 1830 | bpf_program__name(prog));
|
| 1831 | }
|
| 1832 | printf("\t} progs;\n");
|
| 1833 | }
|
| 1834 |
|
| 1835 | err = codegen_subskel_datasecs(obj, obj_name);
|
| 1836 | if (err)
|
| 1837 | goto out;
|
| 1838 |
|
| 1839 |
|
| 1840 | codegen("\
|
| 1841 | \n\
|
| 1842 | \n\
|
| 1843 | #ifdef __cplusplus \n\
|
| 1844 | static inline struct %1$s *open(const struct bpf_object *src);\n\
|
| 1845 | static inline void destroy(struct %1$s *skel); \n\
|
| 1846 | #endif /* __cplusplus */ \n\
|
| 1847 | }; \n\
|
| 1848 | \n\
|
| 1849 | static inline void \n\
|
| 1850 | %1$s__destroy(struct %1$s *skel) \n\
|
| 1851 | { \n\
|
| 1852 | if (!skel) \n\
|
| 1853 | return; \n\
|
| 1854 | if (skel->subskel) \n\
|
| 1855 | bpf_object__destroy_subskeleton(skel->subskel);\n\
|
| 1856 | free(skel); \n\
|
| 1857 | } \n\
|
| 1858 | \n\
|
| 1859 | static inline struct %1$s * \n\
|
| 1860 | %1$s__open(const struct bpf_object *src) \n\
|
| 1861 | { \n\
|
| 1862 | struct %1$s *obj; \n\
|
| 1863 | struct bpf_object_subskeleton *s; \n\
|
| 1864 | struct bpf_map_skeleton *map __attribute__((unused));\n\
|
| 1865 | int err; \n\
|
| 1866 | \n\
|
| 1867 | obj = (struct %1$s *)calloc(1, sizeof(*obj)); \n\
|
| 1868 | if (!obj) { \n\
|
| 1869 | err = -ENOMEM; \n\
|
| 1870 | goto err; \n\
|
| 1871 | } \n\
|
| 1872 | s = (struct bpf_object_subskeleton *)calloc(1, sizeof(*s));\n\
|
| 1873 | if (!s) { \n\
|
| 1874 | err = -ENOMEM; \n\
|
| 1875 | goto err; \n\
|
| 1876 | } \n\
|
| 1877 | s->sz = sizeof(*s); \n\
|
| 1878 | s->obj = src; \n\
|
| 1879 | s->var_skel_sz = sizeof(*s->vars); \n\
|
| 1880 | obj->subskel = s; \n\
|
| 1881 | \n\
|
| 1882 | /* vars */ \n\
|
| 1883 | s->var_cnt = %2$d; \n\
|
| 1884 | s->vars = (struct bpf_var_skeleton *)calloc(%2$d, sizeof(*s->vars));\n\
|
| 1885 | if (!s->vars) { \n\
|
| 1886 | err = -ENOMEM; \n\
|
| 1887 | goto err; \n\
|
| 1888 | } \n\
|
| 1889 | ",
|
| 1890 | obj_name, var_cnt
|
| 1891 | );
|
| 1892 |
|
| 1893 |
|
| 1894 | bpf_object__for_each_map(map, obj) {
|
| 1895 | if (!is_mmapable_map(map, ident, sizeof(ident)))
|
| 1896 | continue;
|
| 1897 |
|
| 1898 | map_type_id = bpf_map__btf_value_type_id(map);
|
| 1899 | if (map_type_id <= 0)
|
| 1900 |
|
| 1901 | continue;
|
| 1902 |
|
| 1903 | map_type = btf__type_by_id(btf, map_type_id);
|
| 1904 | var = btf_var_secinfos(map_type);
|
| 1905 | len = btf_vlen(map_type);
|
| 1906 | for (i = 0; i < len; i++, var++) {
|
| 1907 | var_type = btf__type_by_id(btf, var->type);
|
| 1908 | var_name = btf__name_by_offset(btf, var_type->name_off);
|
| 1909 |
|
| 1910 | if (btf_var(var_type)->linkage == BTF_VAR_STATIC)
|
| 1911 | continue;
|
| 1912 |
|
| 1913 | |
| 1914 | * field access operator i.e. maps%s becomes maps.data
|
| 1915 |
|
| 1916 | codegen("\
|
| 1917 | \n\
|
| 1918 | \n\
|
| 1919 | s->vars[%3$d].name = \"%1$s\"; \n\
|
| 1920 | s->vars[%3$d].map = &obj->maps.%2$s; \n\
|
| 1921 | s->vars[%3$d].addr = (void **) &obj->%2$s.%1$s;\n\
|
| 1922 | ", var_name, ident, var_idx);
|
| 1923 |
|
| 1924 | var_idx++;
|
| 1925 | }
|
| 1926 | }
|
| 1927 |
|
| 1928 | codegen_maps_skeleton(obj, map_cnt, false , false );
|
| 1929 | codegen_progs_skeleton(obj, prog_cnt, false );
|
| 1930 |
|
| 1931 | codegen("\
|
| 1932 | \n\
|
| 1933 | \n\
|
| 1934 | err = bpf_object__open_subskeleton(s); \n\
|
| 1935 | if (err) \n\
|
| 1936 | goto err; \n\
|
| 1937 | \n\
|
| 1938 | ");
|
| 1939 |
|
| 1940 | gen_st_ops_shadow_init(btf, obj);
|
| 1941 |
|
| 1942 | codegen("\
|
| 1943 | \n\
|
| 1944 | return obj; \n\
|
| 1945 | err: \n\
|
| 1946 | %1$s__destroy(obj); \n\
|
| 1947 | errno = -err; \n\
|
| 1948 | return NULL; \n\
|
| 1949 | } \n\
|
| 1950 | \n\
|
| 1951 | #ifdef __cplusplus \n\
|
| 1952 | struct %1$s *%1$s::open(const struct bpf_object *src) { return %1$s__open(src); }\n\
|
| 1953 | void %1$s::destroy(struct %1$s *skel) { %1$s__destroy(skel); }\n\
|
| 1954 | #endif /* __cplusplus */ \n\
|
| 1955 | \n\
|
| 1956 | #endif /* %2$s */ \n\
|
| 1957 | ",
|
| 1958 | obj_name, header_guard);
|
| 1959 | err = 0;
|
| 1960 | out:
|
| 1961 | bpf_object__close(obj);
|
| 1962 | if (obj_data)
|
| 1963 | munmap(obj_data, mmap_sz);
|
| 1964 | close(fd);
|
| 1965 | return err;
|
| 1966 | }
|
| 1967 |
|
| 1968 | static int do_object(int argc, char **argv)
|
| 1969 | {
|
| 1970 | struct bpf_linker *linker;
|
| 1971 | const char *output_file, *file;
|
| 1972 | int err = 0;
|
| 1973 |
|
| 1974 | if (!REQ_ARGS(2)) {
|
| 1975 | usage();
|
| 1976 | return -1;
|
| 1977 | }
|
| 1978 |
|
| 1979 | output_file = GET_ARG();
|
| 1980 |
|
| 1981 | linker = bpf_linker__new(output_file, NULL);
|
| 1982 | if (!linker) {
|
| 1983 | p_err("failed to create BPF linker instance");
|
| 1984 | return -1;
|
| 1985 | }
|
| 1986 |
|
| 1987 | while (argc) {
|
| 1988 | file = GET_ARG();
|
| 1989 |
|
| 1990 | err = bpf_linker__add_file(linker, file, NULL);
|
| 1991 | if (err) {
|
| 1992 | p_err("failed to link '%s': %s (%d)", file, strerror(errno), errno);
|
| 1993 | goto out;
|
| 1994 | }
|
| 1995 | }
|
| 1996 |
|
| 1997 | err = bpf_linker__finalize(linker);
|
| 1998 | if (err) {
|
| 1999 | p_err("failed to finalize ELF file: %s (%d)", strerror(errno), errno);
|
| 2000 | goto out;
|
| 2001 | }
|
| 2002 |
|
| 2003 | err = 0;
|
| 2004 | out:
|
| 2005 | bpf_linker__free(linker);
|
| 2006 | return err;
|
| 2007 | }
|
| 2008 |
|
| 2009 | static int do_help(int argc, char **argv)
|
| 2010 | {
|
| 2011 | if (json_output) {
|
| 2012 | jsonw_null(json_wtr);
|
| 2013 | return 0;
|
| 2014 | }
|
| 2015 |
|
| 2016 | fprintf(stderr,
|
| 2017 | "Usage: %1$s %2$s object OUTPUT_FILE INPUT_FILE [INPUT_FILE...]\n"
|
| 2018 | " %1$s %2$s skeleton FILE [name OBJECT_NAME]\n"
|
| 2019 | " %1$s %2$s subskeleton FILE [name OBJECT_NAME]\n"
|
| 2020 | " %1$s %2$s min_core_btf INPUT OUTPUT OBJECT [OBJECT...]\n"
|
| 2021 | " %1$s %2$s help\n"
|
| 2022 | "\n"
|
| 2023 | " " HELP_SPEC_OPTIONS " |\n"
|
| 2024 | " {-L|--use-loader} | [ {-S|--sign } {-k} <private_key.pem> {-i} <certificate.x509> ]}\n"
|
| 2025 | "",
|
| 2026 | bin_name, "gen");
|
| 2027 |
|
| 2028 | return 0;
|
| 2029 | }
|
| 2030 |
|
| 2031 | static int btf_save_raw(const struct btf *btf, const char *path)
|
| 2032 | {
|
| 2033 | const void *data;
|
| 2034 | FILE *f = NULL;
|
| 2035 | __u32 data_sz;
|
| 2036 | int err = 0;
|
| 2037 |
|
| 2038 | data = btf__raw_data(btf, &data_sz);
|
| 2039 | if (!data)
|
| 2040 | return -ENOMEM;
|
| 2041 |
|
| 2042 | f = fopen(path, "wb");
|
| 2043 | if (!f)
|
| 2044 | return -errno;
|
| 2045 |
|
| 2046 | if (fwrite(data, 1, data_sz, f) != data_sz)
|
| 2047 | err = -errno;
|
| 2048 |
|
| 2049 | fclose(f);
|
| 2050 | return err;
|
| 2051 | }
|
| 2052 |
|
| 2053 | struct btfgen_info {
|
| 2054 | struct btf *src_btf;
|
| 2055 | struct btf *marked_btf;
|
| 2056 | };
|
| 2057 |
|
| 2058 | static size_t btfgen_hash_fn(long key, void *ctx)
|
| 2059 | {
|
| 2060 | return key;
|
| 2061 | }
|
| 2062 |
|
| 2063 | static bool btfgen_equal_fn(long k1, long k2, void *ctx)
|
| 2064 | {
|
| 2065 | return k1 == k2;
|
| 2066 | }
|
| 2067 |
|
| 2068 | static void btfgen_free_info(struct btfgen_info *info)
|
| 2069 | {
|
| 2070 | if (!info)
|
| 2071 | return;
|
| 2072 |
|
| 2073 | btf__free(info->src_btf);
|
| 2074 | btf__free(info->marked_btf);
|
| 2075 |
|
| 2076 | free(info);
|
| 2077 | }
|
| 2078 |
|
| 2079 | static struct btfgen_info *
|
| 2080 | btfgen_new_info(const char *targ_btf_path)
|
| 2081 | {
|
| 2082 | struct btfgen_info *info;
|
| 2083 | int err;
|
| 2084 |
|
| 2085 | info = calloc(1, sizeof(*info));
|
| 2086 | if (!info)
|
| 2087 | return NULL;
|
| 2088 |
|
| 2089 | info->src_btf = btf__parse(targ_btf_path, NULL);
|
| 2090 | if (!info->src_btf) {
|
| 2091 | err = -errno;
|
| 2092 | p_err("failed parsing '%s' BTF file: %s", targ_btf_path, strerror(errno));
|
| 2093 | goto err_out;
|
| 2094 | }
|
| 2095 |
|
| 2096 | info->marked_btf = btf__parse(targ_btf_path, NULL);
|
| 2097 | if (!info->marked_btf) {
|
| 2098 | err = -errno;
|
| 2099 | p_err("failed parsing '%s' BTF file: %s", targ_btf_path, strerror(errno));
|
| 2100 | goto err_out;
|
| 2101 | }
|
| 2102 |
|
| 2103 | return info;
|
| 2104 |
|
| 2105 | err_out:
|
| 2106 | btfgen_free_info(info);
|
| 2107 | errno = -err;
|
| 2108 | return NULL;
|
| 2109 | }
|
| 2110 |
|
| 2111 | #define MARKED UINT32_MAX
|
| 2112 |
|
| 2113 | static void btfgen_mark_member(struct btfgen_info *info, int type_id, int idx)
|
| 2114 | {
|
| 2115 | const struct btf_type *t = btf__type_by_id(info->marked_btf, type_id);
|
| 2116 | struct btf_member *m = btf_members(t) + idx;
|
| 2117 |
|
| 2118 | m->name_off = MARKED;
|
| 2119 | }
|
| 2120 |
|
| 2121 | static int
|
| 2122 | btfgen_mark_type(struct btfgen_info *info, unsigned int type_id, bool follow_pointers)
|
| 2123 | {
|
| 2124 | const struct btf_type *btf_type = btf__type_by_id(info->src_btf, type_id);
|
| 2125 | struct btf_type *cloned_type;
|
| 2126 | struct btf_param *param;
|
| 2127 | struct btf_array *array;
|
| 2128 | __u32 i;
|
| 2129 | int err;
|
| 2130 |
|
| 2131 | if (type_id == 0)
|
| 2132 | return 0;
|
| 2133 |
|
| 2134 |
|
| 2135 | cloned_type = (struct btf_type *) btf__type_by_id(info->marked_btf, type_id);
|
| 2136 | cloned_type->name_off = MARKED;
|
| 2137 |
|
| 2138 |
|
| 2139 | switch (btf_kind(btf_type)) {
|
| 2140 | case BTF_KIND_UNKN:
|
| 2141 | case BTF_KIND_INT:
|
| 2142 | case BTF_KIND_FLOAT:
|
| 2143 | case BTF_KIND_ENUM:
|
| 2144 | case BTF_KIND_ENUM64:
|
| 2145 | case BTF_KIND_STRUCT:
|
| 2146 | case BTF_KIND_UNION:
|
| 2147 | break;
|
| 2148 | case BTF_KIND_PTR:
|
| 2149 | if (follow_pointers) {
|
| 2150 | err = btfgen_mark_type(info, btf_type->type, follow_pointers);
|
| 2151 | if (err)
|
| 2152 | return err;
|
| 2153 | }
|
| 2154 | break;
|
| 2155 | case BTF_KIND_CONST:
|
| 2156 | case BTF_KIND_RESTRICT:
|
| 2157 | case BTF_KIND_VOLATILE:
|
| 2158 | case BTF_KIND_TYPEDEF:
|
| 2159 | err = btfgen_mark_type(info, btf_type->type, follow_pointers);
|
| 2160 | if (err)
|
| 2161 | return err;
|
| 2162 | break;
|
| 2163 | case BTF_KIND_ARRAY:
|
| 2164 | array = btf_array(btf_type);
|
| 2165 |
|
| 2166 |
|
| 2167 | err = btfgen_mark_type(info, array->type, follow_pointers);
|
| 2168 |
|
| 2169 | err = err ? : btfgen_mark_type(info, array->index_type, follow_pointers);
|
| 2170 | if (err)
|
| 2171 | return err;
|
| 2172 | break;
|
| 2173 | case BTF_KIND_FUNC_PROTO:
|
| 2174 |
|
| 2175 | err = btfgen_mark_type(info, btf_type->type, follow_pointers);
|
| 2176 | if (err)
|
| 2177 | return err;
|
| 2178 |
|
| 2179 |
|
| 2180 | param = btf_params(btf_type);
|
| 2181 | for (i = 0; i < btf_vlen(btf_type); i++) {
|
| 2182 | err = btfgen_mark_type(info, param->type, follow_pointers);
|
| 2183 | if (err)
|
| 2184 | return err;
|
| 2185 | param++;
|
| 2186 | }
|
| 2187 | break;
|
| 2188 |
|
| 2189 | default:
|
| 2190 | p_err("unsupported kind: %s (%u)", btf_kind_str(btf_type), type_id);
|
| 2191 | return -EINVAL;
|
| 2192 | }
|
| 2193 |
|
| 2194 | return 0;
|
| 2195 | }
|
| 2196 |
|
| 2197 | static int btfgen_record_field_relo(struct btfgen_info *info, struct bpf_core_spec *targ_spec)
|
| 2198 | {
|
| 2199 | struct btf *btf = info->src_btf;
|
| 2200 | const struct btf_type *btf_type;
|
| 2201 | struct btf_member *btf_member;
|
| 2202 | struct btf_array *array;
|
| 2203 | unsigned int type_id = targ_spec->root_type_id;
|
| 2204 | int idx, err;
|
| 2205 |
|
| 2206 |
|
| 2207 | btf_type = btf__type_by_id(btf, type_id);
|
| 2208 | err = btfgen_mark_type(info, type_id, false);
|
| 2209 | if (err)
|
| 2210 | return err;
|
| 2211 |
|
| 2212 |
|
| 2213 | for (int i = 1; i < targ_spec->raw_len; i++) {
|
| 2214 |
|
| 2215 | while (btf_is_mod(btf_type) || btf_is_typedef(btf_type)) {
|
| 2216 | type_id = btf_type->type;
|
| 2217 | btf_type = btf__type_by_id(btf, type_id);
|
| 2218 | }
|
| 2219 |
|
| 2220 | switch (btf_kind(btf_type)) {
|
| 2221 | case BTF_KIND_STRUCT:
|
| 2222 | case BTF_KIND_UNION:
|
| 2223 | idx = targ_spec->raw_spec[i];
|
| 2224 | btf_member = btf_members(btf_type) + idx;
|
| 2225 |
|
| 2226 |
|
| 2227 | btfgen_mark_member(info, type_id, idx);
|
| 2228 |
|
| 2229 |
|
| 2230 | type_id = btf_member->type;
|
| 2231 | btf_type = btf__type_by_id(btf, type_id);
|
| 2232 | err = btfgen_mark_type(info, type_id, false);
|
| 2233 | if (err)
|
| 2234 | return err;
|
| 2235 | break;
|
| 2236 | case BTF_KIND_ARRAY:
|
| 2237 | array = btf_array(btf_type);
|
| 2238 | type_id = array->type;
|
| 2239 | btf_type = btf__type_by_id(btf, type_id);
|
| 2240 | break;
|
| 2241 | default:
|
| 2242 | p_err("unsupported kind: %s (%u)",
|
| 2243 | btf_kind_str(btf_type), btf_type->type);
|
| 2244 | return -EINVAL;
|
| 2245 | }
|
| 2246 | }
|
| 2247 |
|
| 2248 | return 0;
|
| 2249 | }
|
| 2250 |
|
| 2251 | |
| 2252 | * this function does not rely on the target spec for inferring members, but
|
| 2253 | * uses the associated BTF.
|
| 2254 | *
|
| 2255 | * The `behind_ptr` argument is used to stop marking of composite types reached
|
| 2256 | * through a pointer. This way, we can keep BTF size in check while providing
|
| 2257 | * reasonable match semantics.
|
| 2258 |
|
| 2259 | static int btfgen_mark_type_match(struct btfgen_info *info, __u32 type_id, bool behind_ptr)
|
| 2260 | {
|
| 2261 | const struct btf_type *btf_type;
|
| 2262 | struct btf *btf = info->src_btf;
|
| 2263 | struct btf_type *cloned_type;
|
| 2264 | int err;
|
| 2265 | __u32 i;
|
| 2266 |
|
| 2267 | if (type_id == 0)
|
| 2268 | return 0;
|
| 2269 |
|
| 2270 | btf_type = btf__type_by_id(btf, type_id);
|
| 2271 |
|
| 2272 | cloned_type = (struct btf_type *)btf__type_by_id(info->marked_btf, type_id);
|
| 2273 | cloned_type->name_off = MARKED;
|
| 2274 |
|
| 2275 | switch (btf_kind(btf_type)) {
|
| 2276 | case BTF_KIND_UNKN:
|
| 2277 | case BTF_KIND_INT:
|
| 2278 | case BTF_KIND_FLOAT:
|
| 2279 | case BTF_KIND_ENUM:
|
| 2280 | case BTF_KIND_ENUM64:
|
| 2281 | break;
|
| 2282 | case BTF_KIND_STRUCT:
|
| 2283 | case BTF_KIND_UNION: {
|
| 2284 | struct btf_member *m = btf_members(btf_type);
|
| 2285 | __u32 vlen = btf_vlen(btf_type);
|
| 2286 |
|
| 2287 | if (behind_ptr)
|
| 2288 | break;
|
| 2289 |
|
| 2290 | for (i = 0; i < vlen; i++, m++) {
|
| 2291 |
|
| 2292 | btfgen_mark_member(info, type_id, i);
|
| 2293 |
|
| 2294 |
|
| 2295 | err = btfgen_mark_type_match(info, m->type, false);
|
| 2296 | if (err)
|
| 2297 | return err;
|
| 2298 | }
|
| 2299 | break;
|
| 2300 | }
|
| 2301 | case BTF_KIND_CONST:
|
| 2302 | case BTF_KIND_FWD:
|
| 2303 | case BTF_KIND_RESTRICT:
|
| 2304 | case BTF_KIND_TYPEDEF:
|
| 2305 | case BTF_KIND_VOLATILE:
|
| 2306 | return btfgen_mark_type_match(info, btf_type->type, behind_ptr);
|
| 2307 | case BTF_KIND_PTR:
|
| 2308 | return btfgen_mark_type_match(info, btf_type->type, true);
|
| 2309 | case BTF_KIND_ARRAY: {
|
| 2310 | struct btf_array *array;
|
| 2311 |
|
| 2312 | array = btf_array(btf_type);
|
| 2313 |
|
| 2314 | err = btfgen_mark_type_match(info, array->type, false);
|
| 2315 |
|
| 2316 | err = err ? : btfgen_mark_type_match(info, array->index_type, false);
|
| 2317 | if (err)
|
| 2318 | return err;
|
| 2319 | break;
|
| 2320 | }
|
| 2321 | case BTF_KIND_FUNC_PROTO: {
|
| 2322 | __u32 vlen = btf_vlen(btf_type);
|
| 2323 | struct btf_param *param;
|
| 2324 |
|
| 2325 |
|
| 2326 | err = btfgen_mark_type_match(info, btf_type->type, false);
|
| 2327 | if (err)
|
| 2328 | return err;
|
| 2329 |
|
| 2330 |
|
| 2331 | param = btf_params(btf_type);
|
| 2332 | for (i = 0; i < vlen; i++) {
|
| 2333 | err = btfgen_mark_type_match(info, param->type, false);
|
| 2334 | if (err)
|
| 2335 | return err;
|
| 2336 | param++;
|
| 2337 | }
|
| 2338 | break;
|
| 2339 | }
|
| 2340 |
|
| 2341 | default:
|
| 2342 | p_err("unsupported kind: %s (%u)", btf_kind_str(btf_type), type_id);
|
| 2343 | return -EINVAL;
|
| 2344 | }
|
| 2345 |
|
| 2346 | return 0;
|
| 2347 | }
|
| 2348 |
|
| 2349 | |
| 2350 | * this function does not rely on the target spec for inferring members, but
|
| 2351 | * uses the associated BTF.
|
| 2352 |
|
| 2353 | static int btfgen_record_type_match_relo(struct btfgen_info *info, struct bpf_core_spec *targ_spec)
|
| 2354 | {
|
| 2355 | return btfgen_mark_type_match(info, targ_spec->root_type_id, false);
|
| 2356 | }
|
| 2357 |
|
| 2358 | static int btfgen_record_type_relo(struct btfgen_info *info, struct bpf_core_spec *targ_spec)
|
| 2359 | {
|
| 2360 | return btfgen_mark_type(info, targ_spec->root_type_id, true);
|
| 2361 | }
|
| 2362 |
|
| 2363 | static int btfgen_record_enumval_relo(struct btfgen_info *info, struct bpf_core_spec *targ_spec)
|
| 2364 | {
|
| 2365 | return btfgen_mark_type(info, targ_spec->root_type_id, false);
|
| 2366 | }
|
| 2367 |
|
| 2368 | static int btfgen_record_reloc(struct btfgen_info *info, struct bpf_core_spec *res)
|
| 2369 | {
|
| 2370 | switch (res->relo_kind) {
|
| 2371 | case BPF_CORE_FIELD_BYTE_OFFSET:
|
| 2372 | case BPF_CORE_FIELD_BYTE_SIZE:
|
| 2373 | case BPF_CORE_FIELD_EXISTS:
|
| 2374 | case BPF_CORE_FIELD_SIGNED:
|
| 2375 | case BPF_CORE_FIELD_LSHIFT_U64:
|
| 2376 | case BPF_CORE_FIELD_RSHIFT_U64:
|
| 2377 | return btfgen_record_field_relo(info, res);
|
| 2378 | case BPF_CORE_TYPE_ID_LOCAL:
|
| 2379 | return 0;
|
| 2380 | case BPF_CORE_TYPE_ID_TARGET:
|
| 2381 | case BPF_CORE_TYPE_EXISTS:
|
| 2382 | case BPF_CORE_TYPE_SIZE:
|
| 2383 | return btfgen_record_type_relo(info, res);
|
| 2384 | case BPF_CORE_TYPE_MATCHES:
|
| 2385 | return btfgen_record_type_match_relo(info, res);
|
| 2386 | case BPF_CORE_ENUMVAL_EXISTS:
|
| 2387 | case BPF_CORE_ENUMVAL_VALUE:
|
| 2388 | return btfgen_record_enumval_relo(info, res);
|
| 2389 | default:
|
| 2390 | return -EINVAL;
|
| 2391 | }
|
| 2392 | }
|
| 2393 |
|
| 2394 | static struct bpf_core_cand_list *
|
| 2395 | btfgen_find_cands(const struct btf *local_btf, const struct btf *targ_btf, __u32 local_id)
|
| 2396 | {
|
| 2397 | const struct btf_type *local_type;
|
| 2398 | struct bpf_core_cand_list *cands = NULL;
|
| 2399 | struct bpf_core_cand local_cand = {};
|
| 2400 | size_t local_essent_len;
|
| 2401 | const char *local_name;
|
| 2402 | int err;
|
| 2403 |
|
| 2404 | local_cand.btf = local_btf;
|
| 2405 | local_cand.id = local_id;
|
| 2406 |
|
| 2407 | local_type = btf__type_by_id(local_btf, local_id);
|
| 2408 | if (!local_type) {
|
| 2409 | err = -EINVAL;
|
| 2410 | goto err_out;
|
| 2411 | }
|
| 2412 |
|
| 2413 | local_name = btf__name_by_offset(local_btf, local_type->name_off);
|
| 2414 | if (!local_name) {
|
| 2415 | err = -EINVAL;
|
| 2416 | goto err_out;
|
| 2417 | }
|
| 2418 | local_essent_len = bpf_core_essential_name_len(local_name);
|
| 2419 |
|
| 2420 | cands = calloc(1, sizeof(*cands));
|
| 2421 | if (!cands)
|
| 2422 | return NULL;
|
| 2423 |
|
| 2424 | err = bpf_core_add_cands(&local_cand, local_essent_len, targ_btf, "vmlinux", 1, cands);
|
| 2425 | if (err)
|
| 2426 | goto err_out;
|
| 2427 |
|
| 2428 | return cands;
|
| 2429 |
|
| 2430 | err_out:
|
| 2431 | bpf_core_free_cands(cands);
|
| 2432 | errno = -err;
|
| 2433 | return NULL;
|
| 2434 | }
|
| 2435 |
|
| 2436 |
|
| 2437 | static int btfgen_record_obj(struct btfgen_info *info, const char *obj_path)
|
| 2438 | {
|
| 2439 | const struct btf_ext_info_sec *sec;
|
| 2440 | const struct bpf_core_relo *relo;
|
| 2441 | const struct btf_ext_info *seg;
|
| 2442 | struct hashmap_entry *entry;
|
| 2443 | struct hashmap *cand_cache = NULL;
|
| 2444 | struct btf_ext *btf_ext = NULL;
|
| 2445 | unsigned int relo_idx;
|
| 2446 | struct btf *btf = NULL;
|
| 2447 | size_t i;
|
| 2448 | int err;
|
| 2449 |
|
| 2450 | btf = btf__parse(obj_path, &btf_ext);
|
| 2451 | if (!btf) {
|
| 2452 | err = -errno;
|
| 2453 | p_err("failed to parse BPF object '%s': %s", obj_path, strerror(errno));
|
| 2454 | return err;
|
| 2455 | }
|
| 2456 |
|
| 2457 | if (!btf_ext) {
|
| 2458 | p_err("failed to parse BPF object '%s': section %s not found",
|
| 2459 | obj_path, BTF_EXT_ELF_SEC);
|
| 2460 | err = -EINVAL;
|
| 2461 | goto out;
|
| 2462 | }
|
| 2463 |
|
| 2464 | if (btf_ext->core_relo_info.len == 0) {
|
| 2465 | err = 0;
|
| 2466 | goto out;
|
| 2467 | }
|
| 2468 |
|
| 2469 | cand_cache = hashmap__new(btfgen_hash_fn, btfgen_equal_fn, NULL);
|
| 2470 | if (IS_ERR(cand_cache)) {
|
| 2471 | err = PTR_ERR(cand_cache);
|
| 2472 | goto out;
|
| 2473 | }
|
| 2474 |
|
| 2475 | seg = &btf_ext->core_relo_info;
|
| 2476 | for_each_btf_ext_sec(seg, sec) {
|
| 2477 | for_each_btf_ext_rec(seg, sec, relo_idx, relo) {
|
| 2478 | struct bpf_core_spec specs_scratch[3] = {};
|
| 2479 | struct bpf_core_relo_res targ_res = {};
|
| 2480 | struct bpf_core_cand_list *cands = NULL;
|
| 2481 | const char *sec_name = btf__name_by_offset(btf, sec->sec_name_off);
|
| 2482 |
|
| 2483 | if (relo->kind != BPF_CORE_TYPE_ID_LOCAL &&
|
| 2484 | !hashmap__find(cand_cache, relo->type_id, &cands)) {
|
| 2485 | cands = btfgen_find_cands(btf, info->src_btf, relo->type_id);
|
| 2486 | if (!cands) {
|
| 2487 | err = -errno;
|
| 2488 | goto out;
|
| 2489 | }
|
| 2490 |
|
| 2491 | err = hashmap__set(cand_cache, relo->type_id, cands,
|
| 2492 | NULL, NULL);
|
| 2493 | if (err)
|
| 2494 | goto out;
|
| 2495 | }
|
| 2496 |
|
| 2497 | err = bpf_core_calc_relo_insn(sec_name, relo, relo_idx, btf, cands,
|
| 2498 | specs_scratch, &targ_res);
|
| 2499 | if (err)
|
| 2500 | goto out;
|
| 2501 |
|
| 2502 |
|
| 2503 | err = btfgen_record_reloc(info, &specs_scratch[2]);
|
| 2504 | if (err)
|
| 2505 | goto out;
|
| 2506 | }
|
| 2507 | }
|
| 2508 |
|
| 2509 | out:
|
| 2510 | btf__free(btf);
|
| 2511 | btf_ext__free(btf_ext);
|
| 2512 |
|
| 2513 | if (!IS_ERR_OR_NULL(cand_cache)) {
|
| 2514 | hashmap__for_each_entry(cand_cache, entry, i) {
|
| 2515 | bpf_core_free_cands(entry->pvalue);
|
| 2516 | }
|
| 2517 | hashmap__free(cand_cache);
|
| 2518 | }
|
| 2519 |
|
| 2520 | return err;
|
| 2521 | }
|
| 2522 |
|
| 2523 |
|
| 2524 | static struct btf *btfgen_get_btf(struct btfgen_info *info)
|
| 2525 | {
|
| 2526 | struct btf *btf_new = NULL;
|
| 2527 | unsigned int *ids = NULL;
|
| 2528 | unsigned int n = btf__type_cnt(info->marked_btf);
|
| 2529 | int err = 0;
|
| 2530 | __u32 i;
|
| 2531 |
|
| 2532 | btf_new = btf__new_empty();
|
| 2533 | if (!btf_new) {
|
| 2534 | err = -errno;
|
| 2535 | goto err_out;
|
| 2536 | }
|
| 2537 |
|
| 2538 | ids = calloc(n, sizeof(*ids));
|
| 2539 | if (!ids) {
|
| 2540 | err = -errno;
|
| 2541 | goto err_out;
|
| 2542 | }
|
| 2543 |
|
| 2544 |
|
| 2545 | for (i = 1; i < n; i++) {
|
| 2546 | const struct btf_type *cloned_type, *type;
|
| 2547 | const char *name;
|
| 2548 | int new_id;
|
| 2549 |
|
| 2550 | cloned_type = btf__type_by_id(info->marked_btf, i);
|
| 2551 |
|
| 2552 | if (cloned_type->name_off != MARKED)
|
| 2553 | continue;
|
| 2554 |
|
| 2555 | type = btf__type_by_id(info->src_btf, i);
|
| 2556 |
|
| 2557 |
|
| 2558 | if (btf_is_composite(type)) {
|
| 2559 | struct btf_member *cloned_m, *m;
|
| 2560 | __u32 vlen, idx_src;
|
| 2561 |
|
| 2562 | name = btf__str_by_offset(info->src_btf, type->name_off);
|
| 2563 |
|
| 2564 | if (btf_is_struct(type))
|
| 2565 | err = btf__add_struct(btf_new, name, type->size);
|
| 2566 | else
|
| 2567 | err = btf__add_union(btf_new, name, type->size);
|
| 2568 |
|
| 2569 | if (err < 0)
|
| 2570 | goto err_out;
|
| 2571 | new_id = err;
|
| 2572 |
|
| 2573 | cloned_m = btf_members(cloned_type);
|
| 2574 | m = btf_members(type);
|
| 2575 | vlen = btf_vlen(cloned_type);
|
| 2576 | for (idx_src = 0; idx_src < vlen; idx_src++, cloned_m++, m++) {
|
| 2577 |
|
| 2578 | if (cloned_m->name_off != MARKED)
|
| 2579 | continue;
|
| 2580 |
|
| 2581 | name = btf__str_by_offset(info->src_btf, m->name_off);
|
| 2582 | err = btf__add_field(btf_new, name, m->type,
|
| 2583 | btf_member_bit_offset(cloned_type, idx_src),
|
| 2584 | btf_member_bitfield_size(cloned_type, idx_src));
|
| 2585 | if (err < 0)
|
| 2586 | goto err_out;
|
| 2587 | }
|
| 2588 | } else {
|
| 2589 | err = btf__add_type(btf_new, info->src_btf, type);
|
| 2590 | if (err < 0)
|
| 2591 | goto err_out;
|
| 2592 | new_id = err;
|
| 2593 | }
|
| 2594 |
|
| 2595 |
|
| 2596 | ids[i] = new_id;
|
| 2597 | }
|
| 2598 |
|
| 2599 |
|
| 2600 | for (i = 1; i < btf__type_cnt(btf_new); i++) {
|
| 2601 | struct btf_type *btf_type = (struct btf_type *) btf__type_by_id(btf_new, i);
|
| 2602 | struct btf_field_iter it;
|
| 2603 | __u32 *type_id;
|
| 2604 |
|
| 2605 | err = btf_field_iter_init(&it, btf_type, BTF_FIELD_ITER_IDS);
|
| 2606 | if (err)
|
| 2607 | goto err_out;
|
| 2608 |
|
| 2609 | while ((type_id = btf_field_iter_next(&it)))
|
| 2610 | *type_id = ids[*type_id];
|
| 2611 | }
|
| 2612 |
|
| 2613 | free(ids);
|
| 2614 | return btf_new;
|
| 2615 |
|
| 2616 | err_out:
|
| 2617 | btf__free(btf_new);
|
| 2618 | free(ids);
|
| 2619 | errno = -err;
|
| 2620 | return NULL;
|
| 2621 | }
|
| 2622 |
|
| 2623 | |
| 2624 | *
|
| 2625 | * The BTFGen algorithm is divided in two main parts: (1) collect the
|
| 2626 | * BTF types that are involved in relocations and (2) generate the BTF
|
| 2627 | * object using the collected types.
|
| 2628 | *
|
| 2629 | * In order to collect the types involved in the relocations, we parse
|
| 2630 | * the BTF and BTF.ext sections of the BPF objects and use
|
| 2631 | * bpf_core_calc_relo_insn() to get the target specification, this
|
| 2632 | * indicates how the types and fields are used in a relocation.
|
| 2633 | *
|
| 2634 | * Types are recorded in different ways according to the kind of the
|
| 2635 | * relocation. For field-based relocations only the members that are
|
| 2636 | * actually used are saved in order to reduce the size of the generated
|
| 2637 | * BTF file. For type-based relocations empty struct / unions are
|
| 2638 | * generated and for enum-based relocations the whole type is saved.
|
| 2639 | *
|
| 2640 | * The second part of the algorithm generates the BTF object. It creates
|
| 2641 | * an empty BTF object and fills it with the types recorded in the
|
| 2642 | * previous step. This function takes care of only adding the structure
|
| 2643 | * and union members that were marked as used and it also fixes up the
|
| 2644 | * type IDs on the generated BTF object.
|
| 2645 |
|
| 2646 | static int minimize_btf(const char *src_btf, const char *dst_btf, const char *objspaths[])
|
| 2647 | {
|
| 2648 | struct btfgen_info *info;
|
| 2649 | struct btf *btf_new = NULL;
|
| 2650 | int err, i;
|
| 2651 |
|
| 2652 | info = btfgen_new_info(src_btf);
|
| 2653 | if (!info) {
|
| 2654 | err = -errno;
|
| 2655 | p_err("failed to allocate info structure: %s", strerror(errno));
|
| 2656 | goto out;
|
| 2657 | }
|
| 2658 |
|
| 2659 | for (i = 0; objspaths[i] != NULL; i++) {
|
| 2660 | err = btfgen_record_obj(info, objspaths[i]);
|
| 2661 | if (err) {
|
| 2662 | p_err("error recording relocations for %s: %s", objspaths[i],
|
| 2663 | strerror(errno));
|
| 2664 | goto out;
|
| 2665 | }
|
| 2666 | }
|
| 2667 |
|
| 2668 | btf_new = btfgen_get_btf(info);
|
| 2669 | if (!btf_new) {
|
| 2670 | err = -errno;
|
| 2671 | p_err("error generating BTF: %s", strerror(errno));
|
| 2672 | goto out;
|
| 2673 | }
|
| 2674 |
|
| 2675 | err = btf_save_raw(btf_new, dst_btf);
|
| 2676 | if (err) {
|
| 2677 | p_err("error saving btf file: %s", strerror(errno));
|
| 2678 | goto out;
|
| 2679 | }
|
| 2680 |
|
| 2681 | out:
|
| 2682 | btf__free(btf_new);
|
| 2683 | btfgen_free_info(info);
|
| 2684 |
|
| 2685 | return err;
|
| 2686 | }
|
| 2687 |
|
| 2688 | static int do_min_core_btf(int argc, char **argv)
|
| 2689 | {
|
| 2690 | const char *input, *output, **objs;
|
| 2691 | int i, err;
|
| 2692 |
|
| 2693 | if (!REQ_ARGS(3)) {
|
| 2694 | usage();
|
| 2695 | return -1;
|
| 2696 | }
|
| 2697 |
|
| 2698 | input = GET_ARG();
|
| 2699 | output = GET_ARG();
|
| 2700 |
|
| 2701 | objs = (const char **) calloc(argc + 1, sizeof(*objs));
|
| 2702 | if (!objs) {
|
| 2703 | p_err("failed to allocate array for object names");
|
| 2704 | return -ENOMEM;
|
| 2705 | }
|
| 2706 |
|
| 2707 | i = 0;
|
| 2708 | while (argc)
|
| 2709 | objs[i++] = GET_ARG();
|
| 2710 |
|
| 2711 | err = minimize_btf(input, output, objs);
|
| 2712 | free(objs);
|
| 2713 | return err;
|
| 2714 | }
|
| 2715 |
|
| 2716 | static const struct cmd cmds[] = {
|
| 2717 | { "object", do_object },
|
| 2718 | { "skeleton", do_skeleton },
|
| 2719 | { "subskeleton", do_subskeleton },
|
| 2720 | { "min_core_btf", do_min_core_btf},
|
| 2721 | { "help", do_help },
|
| 2722 | { 0 }
|
| 2723 | };
|
| 2724 |
|
| 2725 | int do_gen(int argc, char **argv)
|
| 2726 | {
|
| 2727 | return cmd_select(cmds, argc, argv, do_help);
|
| 2728 | }
|