Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 1 | #include <fcntl.h> |
| 2 | #include <stdio.h> |
| 3 | #include <errno.h> |
| 4 | #include <string.h> |
| 5 | #include <unistd.h> |
| 6 | #include <inttypes.h> |
| 7 | |
| 8 | #include "symbol.h" |
Waiman Long | 8fa7d87 | 2014-09-29 16:07:28 -0400 | [diff] [blame] | 9 | #include "machine.h" |
Vladimir Nikulichev | 922d0e4 | 2014-04-17 08:27:01 -0700 | [diff] [blame] | 10 | #include "vdso.h" |
Arnaldo Carvalho de Melo | c506c96 | 2013-12-11 09:15:00 -0300 | [diff] [blame] | 11 | #include <symbol/kallsyms.h> |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 12 | #include "debug.h" |
| 13 | |
David Ahern | e370a3d | 2015-02-18 19:33:37 -0500 | [diff] [blame^] | 14 | #ifndef EM_AARCH64 |
| 15 | #define EM_AARCH64 183 /* ARM 64 bit */ |
| 16 | #endif |
| 17 | |
| 18 | |
Arnaldo Carvalho de Melo | aaba4e1 | 2014-11-24 17:10:52 -0300 | [diff] [blame] | 19 | #ifdef HAVE_CPLUS_DEMANGLE_SUPPORT |
| 20 | extern char *cplus_demangle(const char *, int); |
| 21 | |
| 22 | static inline char *bfd_demangle(void __maybe_unused *v, const char *c, int i) |
| 23 | { |
| 24 | return cplus_demangle(c, i); |
| 25 | } |
| 26 | #else |
| 27 | #ifdef NO_DEMANGLE |
| 28 | static inline char *bfd_demangle(void __maybe_unused *v, |
| 29 | const char __maybe_unused *c, |
| 30 | int __maybe_unused i) |
| 31 | { |
| 32 | return NULL; |
| 33 | } |
| 34 | #else |
| 35 | #define PACKAGE 'perf' |
| 36 | #include <bfd.h> |
| 37 | #endif |
| 38 | #endif |
| 39 | |
Ingo Molnar | 89fe808 | 2013-09-30 12:07:11 +0200 | [diff] [blame] | 40 | #ifndef HAVE_ELF_GETPHDRNUM_SUPPORT |
Adrian Hunter | e955d5c | 2013-09-13 16:49:30 +0300 | [diff] [blame] | 41 | static int elf_getphdrnum(Elf *elf, size_t *dst) |
| 42 | { |
| 43 | GElf_Ehdr gehdr; |
| 44 | GElf_Ehdr *ehdr; |
| 45 | |
| 46 | ehdr = gelf_getehdr(elf, &gehdr); |
| 47 | if (!ehdr) |
| 48 | return -1; |
| 49 | |
| 50 | *dst = ehdr->e_phnum; |
| 51 | |
| 52 | return 0; |
| 53 | } |
| 54 | #endif |
| 55 | |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 56 | #ifndef NT_GNU_BUILD_ID |
| 57 | #define NT_GNU_BUILD_ID 3 |
| 58 | #endif |
| 59 | |
| 60 | /** |
| 61 | * elf_symtab__for_each_symbol - iterate thru all the symbols |
| 62 | * |
| 63 | * @syms: struct elf_symtab instance to iterate |
| 64 | * @idx: uint32_t idx |
| 65 | * @sym: GElf_Sym iterator |
| 66 | */ |
| 67 | #define elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) \ |
| 68 | for (idx = 0, gelf_getsym(syms, idx, &sym);\ |
| 69 | idx < nr_syms; \ |
| 70 | idx++, gelf_getsym(syms, idx, &sym)) |
| 71 | |
| 72 | static inline uint8_t elf_sym__type(const GElf_Sym *sym) |
| 73 | { |
| 74 | return GELF_ST_TYPE(sym->st_info); |
| 75 | } |
| 76 | |
| 77 | static inline int elf_sym__is_function(const GElf_Sym *sym) |
| 78 | { |
Adrian Hunter | a2f3b6b | 2014-07-14 13:02:33 +0300 | [diff] [blame] | 79 | return (elf_sym__type(sym) == STT_FUNC || |
| 80 | elf_sym__type(sym) == STT_GNU_IFUNC) && |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 81 | sym->st_name != 0 && |
| 82 | sym->st_shndx != SHN_UNDEF; |
| 83 | } |
| 84 | |
| 85 | static inline bool elf_sym__is_object(const GElf_Sym *sym) |
| 86 | { |
| 87 | return elf_sym__type(sym) == STT_OBJECT && |
| 88 | sym->st_name != 0 && |
| 89 | sym->st_shndx != SHN_UNDEF; |
| 90 | } |
| 91 | |
| 92 | static inline int elf_sym__is_label(const GElf_Sym *sym) |
| 93 | { |
| 94 | return elf_sym__type(sym) == STT_NOTYPE && |
| 95 | sym->st_name != 0 && |
| 96 | sym->st_shndx != SHN_UNDEF && |
| 97 | sym->st_shndx != SHN_ABS; |
| 98 | } |
| 99 | |
| 100 | static bool elf_sym__is_a(GElf_Sym *sym, enum map_type type) |
| 101 | { |
| 102 | switch (type) { |
| 103 | case MAP__FUNCTION: |
| 104 | return elf_sym__is_function(sym); |
| 105 | case MAP__VARIABLE: |
| 106 | return elf_sym__is_object(sym); |
| 107 | default: |
| 108 | return false; |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | static inline const char *elf_sym__name(const GElf_Sym *sym, |
| 113 | const Elf_Data *symstrs) |
| 114 | { |
| 115 | return symstrs->d_buf + sym->st_name; |
| 116 | } |
| 117 | |
| 118 | static inline const char *elf_sec__name(const GElf_Shdr *shdr, |
| 119 | const Elf_Data *secstrs) |
| 120 | { |
| 121 | return secstrs->d_buf + shdr->sh_name; |
| 122 | } |
| 123 | |
| 124 | static inline int elf_sec__is_text(const GElf_Shdr *shdr, |
| 125 | const Elf_Data *secstrs) |
| 126 | { |
| 127 | return strstr(elf_sec__name(shdr, secstrs), "text") != NULL; |
| 128 | } |
| 129 | |
| 130 | static inline bool elf_sec__is_data(const GElf_Shdr *shdr, |
| 131 | const Elf_Data *secstrs) |
| 132 | { |
| 133 | return strstr(elf_sec__name(shdr, secstrs), "data") != NULL; |
| 134 | } |
| 135 | |
| 136 | static bool elf_sec__is_a(GElf_Shdr *shdr, Elf_Data *secstrs, |
| 137 | enum map_type type) |
| 138 | { |
| 139 | switch (type) { |
| 140 | case MAP__FUNCTION: |
| 141 | return elf_sec__is_text(shdr, secstrs); |
| 142 | case MAP__VARIABLE: |
| 143 | return elf_sec__is_data(shdr, secstrs); |
| 144 | default: |
| 145 | return false; |
| 146 | } |
| 147 | } |
| 148 | |
| 149 | static size_t elf_addr_to_index(Elf *elf, GElf_Addr addr) |
| 150 | { |
| 151 | Elf_Scn *sec = NULL; |
| 152 | GElf_Shdr shdr; |
| 153 | size_t cnt = 1; |
| 154 | |
| 155 | while ((sec = elf_nextscn(elf, sec)) != NULL) { |
| 156 | gelf_getshdr(sec, &shdr); |
| 157 | |
| 158 | if ((addr >= shdr.sh_addr) && |
| 159 | (addr < (shdr.sh_addr + shdr.sh_size))) |
| 160 | return cnt; |
| 161 | |
| 162 | ++cnt; |
| 163 | } |
| 164 | |
| 165 | return -1; |
| 166 | } |
| 167 | |
Masami Hiramatsu | 99ca423 | 2014-01-16 09:39:49 +0000 | [diff] [blame] | 168 | Elf_Scn *elf_section_by_name(Elf *elf, GElf_Ehdr *ep, |
| 169 | GElf_Shdr *shp, const char *name, size_t *idx) |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 170 | { |
| 171 | Elf_Scn *sec = NULL; |
| 172 | size_t cnt = 1; |
| 173 | |
Cody P Schafer | 4927465 | 2012-08-10 15:22:55 -0700 | [diff] [blame] | 174 | /* Elf is corrupted/truncated, avoid calling elf_strptr. */ |
| 175 | if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) |
| 176 | return NULL; |
| 177 | |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 178 | while ((sec = elf_nextscn(elf, sec)) != NULL) { |
| 179 | char *str; |
| 180 | |
| 181 | gelf_getshdr(sec, shp); |
| 182 | str = elf_strptr(elf, ep->e_shstrndx, shp->sh_name); |
Jiri Olsa | 155b3a1 | 2014-03-02 14:32:07 +0100 | [diff] [blame] | 183 | if (str && !strcmp(name, str)) { |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 184 | if (idx) |
| 185 | *idx = cnt; |
Jiri Olsa | 155b3a1 | 2014-03-02 14:32:07 +0100 | [diff] [blame] | 186 | return sec; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 187 | } |
| 188 | ++cnt; |
| 189 | } |
| 190 | |
Jiri Olsa | 155b3a1 | 2014-03-02 14:32:07 +0100 | [diff] [blame] | 191 | return NULL; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 192 | } |
| 193 | |
| 194 | #define elf_section__for_each_rel(reldata, pos, pos_mem, idx, nr_entries) \ |
| 195 | for (idx = 0, pos = gelf_getrel(reldata, 0, &pos_mem); \ |
| 196 | idx < nr_entries; \ |
| 197 | ++idx, pos = gelf_getrel(reldata, idx, &pos_mem)) |
| 198 | |
| 199 | #define elf_section__for_each_rela(reldata, pos, pos_mem, idx, nr_entries) \ |
| 200 | for (idx = 0, pos = gelf_getrela(reldata, 0, &pos_mem); \ |
| 201 | idx < nr_entries; \ |
| 202 | ++idx, pos = gelf_getrela(reldata, idx, &pos_mem)) |
| 203 | |
| 204 | /* |
| 205 | * We need to check if we have a .dynsym, so that we can handle the |
| 206 | * .plt, synthesizing its symbols, that aren't on the symtabs (be it |
| 207 | * .dynsym or .symtab). |
| 208 | * And always look at the original dso, not at debuginfo packages, that |
| 209 | * have the PLT data stripped out (shdr_rel_plt.sh_type == SHT_NOBITS). |
| 210 | */ |
Cody P Schafer | a44f605 | 2012-08-10 15:22:59 -0700 | [diff] [blame] | 211 | int dso__synthesize_plt_symbols(struct dso *dso, struct symsrc *ss, struct map *map, |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 212 | symbol_filter_t filter) |
| 213 | { |
| 214 | uint32_t nr_rel_entries, idx; |
| 215 | GElf_Sym sym; |
| 216 | u64 plt_offset; |
| 217 | GElf_Shdr shdr_plt; |
| 218 | struct symbol *f; |
| 219 | GElf_Shdr shdr_rel_plt, shdr_dynsym; |
| 220 | Elf_Data *reldata, *syms, *symstrs; |
| 221 | Elf_Scn *scn_plt_rel, *scn_symstrs, *scn_dynsym; |
| 222 | size_t dynsym_idx; |
| 223 | GElf_Ehdr ehdr; |
| 224 | char sympltname[1024]; |
| 225 | Elf *elf; |
Cody P Schafer | a44f605 | 2012-08-10 15:22:59 -0700 | [diff] [blame] | 226 | int nr = 0, symidx, err = 0; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 227 | |
David Ahern | f47b58b | 2012-08-19 09:47:14 -0600 | [diff] [blame] | 228 | if (!ss->dynsym) |
| 229 | return 0; |
| 230 | |
Cody P Schafer | a44f605 | 2012-08-10 15:22:59 -0700 | [diff] [blame] | 231 | elf = ss->elf; |
| 232 | ehdr = ss->ehdr; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 233 | |
Cody P Schafer | a44f605 | 2012-08-10 15:22:59 -0700 | [diff] [blame] | 234 | scn_dynsym = ss->dynsym; |
| 235 | shdr_dynsym = ss->dynshdr; |
| 236 | dynsym_idx = ss->dynsym_idx; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 237 | |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 238 | if (scn_dynsym == NULL) |
| 239 | goto out_elf_end; |
| 240 | |
| 241 | scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt, |
| 242 | ".rela.plt", NULL); |
| 243 | if (scn_plt_rel == NULL) { |
| 244 | scn_plt_rel = elf_section_by_name(elf, &ehdr, &shdr_rel_plt, |
| 245 | ".rel.plt", NULL); |
| 246 | if (scn_plt_rel == NULL) |
| 247 | goto out_elf_end; |
| 248 | } |
| 249 | |
| 250 | err = -1; |
| 251 | |
| 252 | if (shdr_rel_plt.sh_link != dynsym_idx) |
| 253 | goto out_elf_end; |
| 254 | |
| 255 | if (elf_section_by_name(elf, &ehdr, &shdr_plt, ".plt", NULL) == NULL) |
| 256 | goto out_elf_end; |
| 257 | |
| 258 | /* |
| 259 | * Fetch the relocation section to find the idxes to the GOT |
| 260 | * and the symbols in the .dynsym they refer to. |
| 261 | */ |
| 262 | reldata = elf_getdata(scn_plt_rel, NULL); |
| 263 | if (reldata == NULL) |
| 264 | goto out_elf_end; |
| 265 | |
| 266 | syms = elf_getdata(scn_dynsym, NULL); |
| 267 | if (syms == NULL) |
| 268 | goto out_elf_end; |
| 269 | |
| 270 | scn_symstrs = elf_getscn(elf, shdr_dynsym.sh_link); |
| 271 | if (scn_symstrs == NULL) |
| 272 | goto out_elf_end; |
| 273 | |
| 274 | symstrs = elf_getdata(scn_symstrs, NULL); |
| 275 | if (symstrs == NULL) |
| 276 | goto out_elf_end; |
| 277 | |
Cody P Schafer | 52f9ddb | 2012-08-10 15:22:51 -0700 | [diff] [blame] | 278 | if (symstrs->d_size == 0) |
| 279 | goto out_elf_end; |
| 280 | |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 281 | nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize; |
| 282 | plt_offset = shdr_plt.sh_offset; |
| 283 | |
| 284 | if (shdr_rel_plt.sh_type == SHT_RELA) { |
| 285 | GElf_Rela pos_mem, *pos; |
| 286 | |
| 287 | elf_section__for_each_rela(reldata, pos, pos_mem, idx, |
| 288 | nr_rel_entries) { |
| 289 | symidx = GELF_R_SYM(pos->r_info); |
| 290 | plt_offset += shdr_plt.sh_entsize; |
| 291 | gelf_getsym(syms, symidx, &sym); |
| 292 | snprintf(sympltname, sizeof(sympltname), |
| 293 | "%s@plt", elf_sym__name(&sym, symstrs)); |
| 294 | |
| 295 | f = symbol__new(plt_offset, shdr_plt.sh_entsize, |
| 296 | STB_GLOBAL, sympltname); |
| 297 | if (!f) |
| 298 | goto out_elf_end; |
| 299 | |
| 300 | if (filter && filter(map, f)) |
| 301 | symbol__delete(f); |
| 302 | else { |
| 303 | symbols__insert(&dso->symbols[map->type], f); |
| 304 | ++nr; |
| 305 | } |
| 306 | } |
| 307 | } else if (shdr_rel_plt.sh_type == SHT_REL) { |
| 308 | GElf_Rel pos_mem, *pos; |
| 309 | elf_section__for_each_rel(reldata, pos, pos_mem, idx, |
| 310 | nr_rel_entries) { |
| 311 | symidx = GELF_R_SYM(pos->r_info); |
| 312 | plt_offset += shdr_plt.sh_entsize; |
| 313 | gelf_getsym(syms, symidx, &sym); |
| 314 | snprintf(sympltname, sizeof(sympltname), |
| 315 | "%s@plt", elf_sym__name(&sym, symstrs)); |
| 316 | |
| 317 | f = symbol__new(plt_offset, shdr_plt.sh_entsize, |
| 318 | STB_GLOBAL, sympltname); |
| 319 | if (!f) |
| 320 | goto out_elf_end; |
| 321 | |
| 322 | if (filter && filter(map, f)) |
| 323 | symbol__delete(f); |
| 324 | else { |
| 325 | symbols__insert(&dso->symbols[map->type], f); |
| 326 | ++nr; |
| 327 | } |
| 328 | } |
| 329 | } |
| 330 | |
| 331 | err = 0; |
| 332 | out_elf_end: |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 333 | if (err == 0) |
| 334 | return nr; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 335 | pr_debug("%s: problems reading %s PLT info.\n", |
| 336 | __func__, dso->long_name); |
| 337 | return 0; |
| 338 | } |
| 339 | |
| 340 | /* |
| 341 | * Align offset to 4 bytes as needed for note name and descriptor data. |
| 342 | */ |
| 343 | #define NOTE_ALIGN(n) (((n) + 3) & -4U) |
| 344 | |
| 345 | static int elf_read_build_id(Elf *elf, void *bf, size_t size) |
| 346 | { |
| 347 | int err = -1; |
| 348 | GElf_Ehdr ehdr; |
| 349 | GElf_Shdr shdr; |
| 350 | Elf_Data *data; |
| 351 | Elf_Scn *sec; |
| 352 | Elf_Kind ek; |
| 353 | void *ptr; |
| 354 | |
| 355 | if (size < BUILD_ID_SIZE) |
| 356 | goto out; |
| 357 | |
| 358 | ek = elf_kind(elf); |
| 359 | if (ek != ELF_K_ELF) |
| 360 | goto out; |
| 361 | |
| 362 | if (gelf_getehdr(elf, &ehdr) == NULL) { |
| 363 | pr_err("%s: cannot get elf header.\n", __func__); |
| 364 | goto out; |
| 365 | } |
| 366 | |
| 367 | /* |
| 368 | * Check following sections for notes: |
| 369 | * '.note.gnu.build-id' |
| 370 | * '.notes' |
| 371 | * '.note' (VDSO specific) |
| 372 | */ |
| 373 | do { |
| 374 | sec = elf_section_by_name(elf, &ehdr, &shdr, |
| 375 | ".note.gnu.build-id", NULL); |
| 376 | if (sec) |
| 377 | break; |
| 378 | |
| 379 | sec = elf_section_by_name(elf, &ehdr, &shdr, |
| 380 | ".notes", NULL); |
| 381 | if (sec) |
| 382 | break; |
| 383 | |
| 384 | sec = elf_section_by_name(elf, &ehdr, &shdr, |
| 385 | ".note", NULL); |
| 386 | if (sec) |
| 387 | break; |
| 388 | |
| 389 | return err; |
| 390 | |
| 391 | } while (0); |
| 392 | |
| 393 | data = elf_getdata(sec, NULL); |
| 394 | if (data == NULL) |
| 395 | goto out; |
| 396 | |
| 397 | ptr = data->d_buf; |
| 398 | while (ptr < (data->d_buf + data->d_size)) { |
| 399 | GElf_Nhdr *nhdr = ptr; |
| 400 | size_t namesz = NOTE_ALIGN(nhdr->n_namesz), |
| 401 | descsz = NOTE_ALIGN(nhdr->n_descsz); |
| 402 | const char *name; |
| 403 | |
| 404 | ptr += sizeof(*nhdr); |
| 405 | name = ptr; |
| 406 | ptr += namesz; |
| 407 | if (nhdr->n_type == NT_GNU_BUILD_ID && |
| 408 | nhdr->n_namesz == sizeof("GNU")) { |
| 409 | if (memcmp(name, "GNU", sizeof("GNU")) == 0) { |
| 410 | size_t sz = min(size, descsz); |
| 411 | memcpy(bf, ptr, sz); |
| 412 | memset(bf + sz, 0, size - sz); |
| 413 | err = descsz; |
| 414 | break; |
| 415 | } |
| 416 | } |
| 417 | ptr += descsz; |
| 418 | } |
| 419 | |
| 420 | out: |
| 421 | return err; |
| 422 | } |
| 423 | |
| 424 | int filename__read_build_id(const char *filename, void *bf, size_t size) |
| 425 | { |
| 426 | int fd, err = -1; |
| 427 | Elf *elf; |
| 428 | |
| 429 | if (size < BUILD_ID_SIZE) |
| 430 | goto out; |
| 431 | |
| 432 | fd = open(filename, O_RDONLY); |
| 433 | if (fd < 0) |
| 434 | goto out; |
| 435 | |
| 436 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); |
| 437 | if (elf == NULL) { |
| 438 | pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename); |
| 439 | goto out_close; |
| 440 | } |
| 441 | |
| 442 | err = elf_read_build_id(elf, bf, size); |
| 443 | |
| 444 | elf_end(elf); |
| 445 | out_close: |
| 446 | close(fd); |
| 447 | out: |
| 448 | return err; |
| 449 | } |
| 450 | |
| 451 | int sysfs__read_build_id(const char *filename, void *build_id, size_t size) |
| 452 | { |
| 453 | int fd, err = -1; |
| 454 | |
| 455 | if (size < BUILD_ID_SIZE) |
| 456 | goto out; |
| 457 | |
| 458 | fd = open(filename, O_RDONLY); |
| 459 | if (fd < 0) |
| 460 | goto out; |
| 461 | |
| 462 | while (1) { |
| 463 | char bf[BUFSIZ]; |
| 464 | GElf_Nhdr nhdr; |
| 465 | size_t namesz, descsz; |
| 466 | |
| 467 | if (read(fd, &nhdr, sizeof(nhdr)) != sizeof(nhdr)) |
| 468 | break; |
| 469 | |
| 470 | namesz = NOTE_ALIGN(nhdr.n_namesz); |
| 471 | descsz = NOTE_ALIGN(nhdr.n_descsz); |
| 472 | if (nhdr.n_type == NT_GNU_BUILD_ID && |
| 473 | nhdr.n_namesz == sizeof("GNU")) { |
| 474 | if (read(fd, bf, namesz) != (ssize_t)namesz) |
| 475 | break; |
| 476 | if (memcmp(bf, "GNU", sizeof("GNU")) == 0) { |
| 477 | size_t sz = min(descsz, size); |
| 478 | if (read(fd, build_id, sz) == (ssize_t)sz) { |
| 479 | memset(build_id + sz, 0, size - sz); |
| 480 | err = 0; |
| 481 | break; |
| 482 | } |
| 483 | } else if (read(fd, bf, descsz) != (ssize_t)descsz) |
| 484 | break; |
| 485 | } else { |
| 486 | int n = namesz + descsz; |
| 487 | if (read(fd, bf, n) != n) |
| 488 | break; |
| 489 | } |
| 490 | } |
| 491 | close(fd); |
| 492 | out: |
| 493 | return err; |
| 494 | } |
| 495 | |
| 496 | int filename__read_debuglink(const char *filename, char *debuglink, |
| 497 | size_t size) |
| 498 | { |
| 499 | int fd, err = -1; |
| 500 | Elf *elf; |
| 501 | GElf_Ehdr ehdr; |
| 502 | GElf_Shdr shdr; |
| 503 | Elf_Data *data; |
| 504 | Elf_Scn *sec; |
| 505 | Elf_Kind ek; |
| 506 | |
| 507 | fd = open(filename, O_RDONLY); |
| 508 | if (fd < 0) |
| 509 | goto out; |
| 510 | |
| 511 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); |
| 512 | if (elf == NULL) { |
| 513 | pr_debug2("%s: cannot read %s ELF file.\n", __func__, filename); |
| 514 | goto out_close; |
| 515 | } |
| 516 | |
| 517 | ek = elf_kind(elf); |
| 518 | if (ek != ELF_K_ELF) |
Chenggang Qin | 784f339 | 2013-10-11 08:27:57 +0800 | [diff] [blame] | 519 | goto out_elf_end; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 520 | |
| 521 | if (gelf_getehdr(elf, &ehdr) == NULL) { |
| 522 | pr_err("%s: cannot get elf header.\n", __func__); |
Chenggang Qin | 784f339 | 2013-10-11 08:27:57 +0800 | [diff] [blame] | 523 | goto out_elf_end; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 524 | } |
| 525 | |
| 526 | sec = elf_section_by_name(elf, &ehdr, &shdr, |
| 527 | ".gnu_debuglink", NULL); |
| 528 | if (sec == NULL) |
Chenggang Qin | 784f339 | 2013-10-11 08:27:57 +0800 | [diff] [blame] | 529 | goto out_elf_end; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 530 | |
| 531 | data = elf_getdata(sec, NULL); |
| 532 | if (data == NULL) |
Chenggang Qin | 784f339 | 2013-10-11 08:27:57 +0800 | [diff] [blame] | 533 | goto out_elf_end; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 534 | |
| 535 | /* the start of this section is a zero-terminated string */ |
| 536 | strncpy(debuglink, data->d_buf, size); |
| 537 | |
Stephane Eranian | 0d3dc5e | 2014-02-20 10:32:55 +0900 | [diff] [blame] | 538 | err = 0; |
| 539 | |
Chenggang Qin | 784f339 | 2013-10-11 08:27:57 +0800 | [diff] [blame] | 540 | out_elf_end: |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 541 | elf_end(elf); |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 542 | out_close: |
| 543 | close(fd); |
| 544 | out: |
| 545 | return err; |
| 546 | } |
| 547 | |
| 548 | static int dso__swap_init(struct dso *dso, unsigned char eidata) |
| 549 | { |
| 550 | static unsigned int const endian = 1; |
| 551 | |
| 552 | dso->needs_swap = DSO_SWAP__NO; |
| 553 | |
| 554 | switch (eidata) { |
| 555 | case ELFDATA2LSB: |
| 556 | /* We are big endian, DSO is little endian. */ |
| 557 | if (*(unsigned char const *)&endian != 1) |
| 558 | dso->needs_swap = DSO_SWAP__YES; |
| 559 | break; |
| 560 | |
| 561 | case ELFDATA2MSB: |
| 562 | /* We are little endian, DSO is big endian. */ |
| 563 | if (*(unsigned char const *)&endian != 0) |
| 564 | dso->needs_swap = DSO_SWAP__YES; |
| 565 | break; |
| 566 | |
| 567 | default: |
| 568 | pr_err("unrecognized DSO data encoding %d\n", eidata); |
| 569 | return -EINVAL; |
| 570 | } |
| 571 | |
| 572 | return 0; |
| 573 | } |
| 574 | |
Namhyung Kim | c00c48f | 2014-11-04 10:14:27 +0900 | [diff] [blame] | 575 | static int decompress_kmodule(struct dso *dso, const char *name, |
| 576 | enum dso_binary_type type) |
| 577 | { |
| 578 | int fd; |
| 579 | const char *ext = strrchr(name, '.'); |
| 580 | char tmpbuf[] = "/tmp/perf-kmod-XXXXXX"; |
| 581 | |
Namhyung Kim | 0b064f4 | 2015-01-29 17:06:42 +0900 | [diff] [blame] | 582 | if (type != DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP && |
| 583 | type != DSO_BINARY_TYPE__GUEST_KMODULE_COMP && |
| 584 | type != DSO_BINARY_TYPE__BUILD_ID_CACHE) |
Namhyung Kim | c00c48f | 2014-11-04 10:14:27 +0900 | [diff] [blame] | 585 | return -1; |
| 586 | |
Namhyung Kim | 0b064f4 | 2015-01-29 17:06:42 +0900 | [diff] [blame] | 587 | if (!ext || !is_supported_compression(ext + 1)) { |
| 588 | ext = strrchr(dso->name, '.'); |
| 589 | if (!ext || !is_supported_compression(ext + 1)) |
| 590 | return -1; |
| 591 | } |
Namhyung Kim | c00c48f | 2014-11-04 10:14:27 +0900 | [diff] [blame] | 592 | |
| 593 | fd = mkstemp(tmpbuf); |
| 594 | if (fd < 0) |
| 595 | return -1; |
| 596 | |
| 597 | if (!decompress_to_file(ext + 1, name, fd)) { |
| 598 | close(fd); |
| 599 | fd = -1; |
| 600 | } |
| 601 | |
| 602 | unlink(tmpbuf); |
| 603 | |
| 604 | return fd; |
| 605 | } |
| 606 | |
Cody P Schafer | 3aafe5a | 2012-08-10 15:23:02 -0700 | [diff] [blame] | 607 | bool symsrc__possibly_runtime(struct symsrc *ss) |
| 608 | { |
| 609 | return ss->dynsym || ss->opdsec; |
| 610 | } |
| 611 | |
Cody P Schafer | d26cd12 | 2012-08-10 15:23:00 -0700 | [diff] [blame] | 612 | bool symsrc__has_symtab(struct symsrc *ss) |
| 613 | { |
| 614 | return ss->symtab != NULL; |
| 615 | } |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 616 | |
| 617 | void symsrc__destroy(struct symsrc *ss) |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 618 | { |
Arnaldo Carvalho de Melo | 74cf249 | 2013-12-27 16:55:14 -0300 | [diff] [blame] | 619 | zfree(&ss->name); |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 620 | elf_end(ss->elf); |
| 621 | close(ss->fd); |
| 622 | } |
| 623 | |
| 624 | int symsrc__init(struct symsrc *ss, struct dso *dso, const char *name, |
| 625 | enum dso_binary_type type) |
| 626 | { |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 627 | int err = -1; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 628 | GElf_Ehdr ehdr; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 629 | Elf *elf; |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 630 | int fd; |
| 631 | |
Namhyung Kim | c00c48f | 2014-11-04 10:14:27 +0900 | [diff] [blame] | 632 | if (dso__needs_decompress(dso)) |
| 633 | fd = decompress_kmodule(dso, name, type); |
| 634 | else |
| 635 | fd = open(name, O_RDONLY); |
| 636 | |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 637 | if (fd < 0) |
| 638 | return -1; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 639 | |
| 640 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); |
| 641 | if (elf == NULL) { |
| 642 | pr_debug("%s: cannot read %s ELF file.\n", __func__, name); |
| 643 | goto out_close; |
| 644 | } |
| 645 | |
| 646 | if (gelf_getehdr(elf, &ehdr) == NULL) { |
| 647 | pr_debug("%s: cannot get elf header.\n", __func__); |
| 648 | goto out_elf_end; |
| 649 | } |
| 650 | |
| 651 | if (dso__swap_init(dso, ehdr.e_ident[EI_DATA])) |
| 652 | goto out_elf_end; |
| 653 | |
| 654 | /* Always reject images with a mismatched build-id: */ |
| 655 | if (dso->has_build_id) { |
| 656 | u8 build_id[BUILD_ID_SIZE]; |
| 657 | |
| 658 | if (elf_read_build_id(elf, build_id, BUILD_ID_SIZE) < 0) |
| 659 | goto out_elf_end; |
| 660 | |
| 661 | if (!dso__build_id_equal(dso, build_id)) |
| 662 | goto out_elf_end; |
| 663 | } |
| 664 | |
Adrian Hunter | c6d8f2a | 2014-07-14 13:02:41 +0300 | [diff] [blame] | 665 | ss->is_64_bit = (gelf_getclass(elf) == ELFCLASS64); |
| 666 | |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 667 | ss->symtab = elf_section_by_name(elf, &ehdr, &ss->symshdr, ".symtab", |
| 668 | NULL); |
| 669 | if (ss->symshdr.sh_type != SHT_SYMTAB) |
| 670 | ss->symtab = NULL; |
| 671 | |
| 672 | ss->dynsym_idx = 0; |
| 673 | ss->dynsym = elf_section_by_name(elf, &ehdr, &ss->dynshdr, ".dynsym", |
| 674 | &ss->dynsym_idx); |
| 675 | if (ss->dynshdr.sh_type != SHT_DYNSYM) |
| 676 | ss->dynsym = NULL; |
| 677 | |
| 678 | ss->opdidx = 0; |
| 679 | ss->opdsec = elf_section_by_name(elf, &ehdr, &ss->opdshdr, ".opd", |
| 680 | &ss->opdidx); |
| 681 | if (ss->opdshdr.sh_type != SHT_PROGBITS) |
| 682 | ss->opdsec = NULL; |
| 683 | |
| 684 | if (dso->kernel == DSO_TYPE_USER) { |
| 685 | GElf_Shdr shdr; |
| 686 | ss->adjust_symbols = (ehdr.e_type == ET_EXEC || |
Adrian Hunter | 0131c4e | 2013-08-07 14:38:50 +0300 | [diff] [blame] | 687 | ehdr.e_type == ET_REL || |
Adrian Hunter | 51682dc | 2014-07-22 16:17:57 +0300 | [diff] [blame] | 688 | dso__is_vdso(dso) || |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 689 | elf_section_by_name(elf, &ehdr, &shdr, |
| 690 | ".gnu.prelink_undo", |
| 691 | NULL) != NULL); |
| 692 | } else { |
Adrian Hunter | 0131c4e | 2013-08-07 14:38:50 +0300 | [diff] [blame] | 693 | ss->adjust_symbols = ehdr.e_type == ET_EXEC || |
| 694 | ehdr.e_type == ET_REL; |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 695 | } |
| 696 | |
| 697 | ss->name = strdup(name); |
| 698 | if (!ss->name) |
| 699 | goto out_elf_end; |
| 700 | |
| 701 | ss->elf = elf; |
| 702 | ss->fd = fd; |
| 703 | ss->ehdr = ehdr; |
| 704 | ss->type = type; |
| 705 | |
| 706 | return 0; |
| 707 | |
| 708 | out_elf_end: |
| 709 | elf_end(elf); |
| 710 | out_close: |
| 711 | close(fd); |
| 712 | return err; |
| 713 | } |
| 714 | |
Adrian Hunter | 39b12f78 | 2013-08-07 14:38:47 +0300 | [diff] [blame] | 715 | /** |
| 716 | * ref_reloc_sym_not_found - has kernel relocation symbol been found. |
| 717 | * @kmap: kernel maps and relocation reference symbol |
| 718 | * |
| 719 | * This function returns %true if we are dealing with the kernel maps and the |
| 720 | * relocation reference symbol has not yet been found. Otherwise %false is |
| 721 | * returned. |
| 722 | */ |
| 723 | static bool ref_reloc_sym_not_found(struct kmap *kmap) |
| 724 | { |
| 725 | return kmap && kmap->ref_reloc_sym && kmap->ref_reloc_sym->name && |
| 726 | !kmap->ref_reloc_sym->unrelocated_addr; |
| 727 | } |
| 728 | |
| 729 | /** |
| 730 | * ref_reloc - kernel relocation offset. |
| 731 | * @kmap: kernel maps and relocation reference symbol |
| 732 | * |
| 733 | * This function returns the offset of kernel addresses as determined by using |
| 734 | * the relocation reference symbol i.e. if the kernel has not been relocated |
| 735 | * then the return value is zero. |
| 736 | */ |
| 737 | static u64 ref_reloc(struct kmap *kmap) |
| 738 | { |
| 739 | if (kmap && kmap->ref_reloc_sym && |
| 740 | kmap->ref_reloc_sym->unrelocated_addr) |
| 741 | return kmap->ref_reloc_sym->addr - |
| 742 | kmap->ref_reloc_sym->unrelocated_addr; |
| 743 | return 0; |
| 744 | } |
| 745 | |
Avi Kivity | 763122a | 2014-09-13 07:15:05 +0300 | [diff] [blame] | 746 | static bool want_demangle(bool is_kernel_sym) |
| 747 | { |
| 748 | return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle; |
| 749 | } |
| 750 | |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 751 | int dso__load_sym(struct dso *dso, struct map *map, |
| 752 | struct symsrc *syms_ss, struct symsrc *runtime_ss, |
Cody P Schafer | d26cd12 | 2012-08-10 15:23:00 -0700 | [diff] [blame] | 753 | symbol_filter_t filter, int kmodule) |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 754 | { |
| 755 | struct kmap *kmap = dso->kernel ? map__kmap(map) : NULL; |
| 756 | struct map *curr_map = map; |
| 757 | struct dso *curr_dso = dso; |
| 758 | Elf_Data *symstrs, *secstrs; |
| 759 | uint32_t nr_syms; |
| 760 | int err = -1; |
| 761 | uint32_t idx; |
| 762 | GElf_Ehdr ehdr; |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 763 | GElf_Shdr shdr; |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 764 | Elf_Data *syms, *opddata = NULL; |
| 765 | GElf_Sym sym; |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 766 | Elf_Scn *sec, *sec_strndx; |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 767 | Elf *elf; |
| 768 | int nr = 0; |
Adrian Hunter | 39b12f78 | 2013-08-07 14:38:47 +0300 | [diff] [blame] | 769 | bool remap_kernel = false, adjust_kernel_syms = false; |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 770 | |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 771 | dso->symtab_type = syms_ss->type; |
Adrian Hunter | c6d8f2a | 2014-07-14 13:02:41 +0300 | [diff] [blame] | 772 | dso->is_64_bit = syms_ss->is_64_bit; |
Adrian Hunter | 0131c4e | 2013-08-07 14:38:50 +0300 | [diff] [blame] | 773 | dso->rel = syms_ss->ehdr.e_type == ET_REL; |
| 774 | |
| 775 | /* |
| 776 | * Modules may already have symbols from kallsyms, but those symbols |
| 777 | * have the wrong values for the dso maps, so remove them. |
| 778 | */ |
| 779 | if (kmodule && syms_ss->symtab) |
| 780 | symbols__delete(&dso->symbols[map->type]); |
Cody P Schafer | 005f929 | 2012-08-10 15:22:58 -0700 | [diff] [blame] | 781 | |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 782 | if (!syms_ss->symtab) { |
Anton Blanchard | d0b0d04 | 2014-09-09 08:59:29 +1000 | [diff] [blame] | 783 | /* |
| 784 | * If the vmlinux is stripped, fail so we will fall back |
| 785 | * to using kallsyms. The vmlinux runtime symbols aren't |
| 786 | * of much use. |
| 787 | */ |
| 788 | if (dso->kernel) |
| 789 | goto out_elf_end; |
| 790 | |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 791 | syms_ss->symtab = syms_ss->dynsym; |
| 792 | syms_ss->symshdr = syms_ss->dynshdr; |
Cody P Schafer | d26cd12 | 2012-08-10 15:23:00 -0700 | [diff] [blame] | 793 | } |
| 794 | |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 795 | elf = syms_ss->elf; |
| 796 | ehdr = syms_ss->ehdr; |
| 797 | sec = syms_ss->symtab; |
| 798 | shdr = syms_ss->symshdr; |
Cody P Schafer | b68e2f9 | 2012-08-10 15:22:57 -0700 | [diff] [blame] | 799 | |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 800 | if (runtime_ss->opdsec) |
| 801 | opddata = elf_rawdata(runtime_ss->opdsec, NULL); |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 802 | |
| 803 | syms = elf_getdata(sec, NULL); |
| 804 | if (syms == NULL) |
| 805 | goto out_elf_end; |
| 806 | |
| 807 | sec = elf_getscn(elf, shdr.sh_link); |
| 808 | if (sec == NULL) |
| 809 | goto out_elf_end; |
| 810 | |
| 811 | symstrs = elf_getdata(sec, NULL); |
| 812 | if (symstrs == NULL) |
| 813 | goto out_elf_end; |
| 814 | |
Adrian Hunter | f247fb8 | 2014-07-31 09:00:46 +0300 | [diff] [blame] | 815 | sec_strndx = elf_getscn(runtime_ss->elf, runtime_ss->ehdr.e_shstrndx); |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 816 | if (sec_strndx == NULL) |
| 817 | goto out_elf_end; |
| 818 | |
| 819 | secstrs = elf_getdata(sec_strndx, NULL); |
| 820 | if (secstrs == NULL) |
| 821 | goto out_elf_end; |
| 822 | |
| 823 | nr_syms = shdr.sh_size / shdr.sh_entsize; |
| 824 | |
| 825 | memset(&sym, 0, sizeof(sym)); |
Adrian Hunter | 39b12f78 | 2013-08-07 14:38:47 +0300 | [diff] [blame] | 826 | |
| 827 | /* |
| 828 | * The kernel relocation symbol is needed in advance in order to adjust |
| 829 | * kernel maps correctly. |
| 830 | */ |
| 831 | if (ref_reloc_sym_not_found(kmap)) { |
| 832 | elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) { |
| 833 | const char *elf_name = elf_sym__name(&sym, symstrs); |
| 834 | |
| 835 | if (strcmp(elf_name, kmap->ref_reloc_sym->name)) |
| 836 | continue; |
| 837 | kmap->ref_reloc_sym->unrelocated_addr = sym.st_value; |
Adrian Hunter | 9176753 | 2014-01-29 16:14:36 +0200 | [diff] [blame] | 838 | map->reloc = kmap->ref_reloc_sym->addr - |
| 839 | kmap->ref_reloc_sym->unrelocated_addr; |
Adrian Hunter | 39b12f78 | 2013-08-07 14:38:47 +0300 | [diff] [blame] | 840 | break; |
| 841 | } |
| 842 | } |
| 843 | |
| 844 | dso->adjust_symbols = runtime_ss->adjust_symbols || ref_reloc(kmap); |
| 845 | /* |
| 846 | * Initial kernel and module mappings do not map to the dso. For |
| 847 | * function mappings, flag the fixups. |
| 848 | */ |
| 849 | if (map->type == MAP__FUNCTION && (dso->kernel || kmodule)) { |
| 850 | remap_kernel = true; |
| 851 | adjust_kernel_syms = dso->adjust_symbols; |
| 852 | } |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 853 | elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) { |
| 854 | struct symbol *f; |
| 855 | const char *elf_name = elf_sym__name(&sym, symstrs); |
| 856 | char *demangled = NULL; |
| 857 | int is_label = elf_sym__is_label(&sym); |
| 858 | const char *section_name; |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 859 | bool used_opd = false; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 860 | |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 861 | if (!is_label && !elf_sym__is_a(&sym, map->type)) |
| 862 | continue; |
| 863 | |
| 864 | /* Reject ARM ELF "mapping symbols": these aren't unique and |
| 865 | * don't identify functions, so will confuse the profile |
| 866 | * output: */ |
| 867 | if (ehdr.e_machine == EM_ARM) { |
| 868 | if (!strcmp(elf_name, "$a") || |
| 869 | !strcmp(elf_name, "$d") || |
| 870 | !strcmp(elf_name, "$t")) |
| 871 | continue; |
| 872 | } |
| 873 | |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 874 | if (runtime_ss->opdsec && sym.st_shndx == runtime_ss->opdidx) { |
| 875 | u32 offset = sym.st_value - syms_ss->opdshdr.sh_addr; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 876 | u64 *opd = opddata->d_buf + offset; |
| 877 | sym.st_value = DSO__SWAP(dso, u64, *opd); |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 878 | sym.st_shndx = elf_addr_to_index(runtime_ss->elf, |
| 879 | sym.st_value); |
| 880 | used_opd = true; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 881 | } |
Namhyung Kim | 3843b05 | 2012-11-21 13:49:44 +0100 | [diff] [blame] | 882 | /* |
| 883 | * When loading symbols in a data mapping, ABS symbols (which |
| 884 | * has a value of SHN_ABS in its st_shndx) failed at |
| 885 | * elf_getscn(). And it marks the loading as a failure so |
| 886 | * already loaded symbols cannot be fixed up. |
| 887 | * |
| 888 | * I'm not sure what should be done. Just ignore them for now. |
| 889 | * - Namhyung Kim |
| 890 | */ |
| 891 | if (sym.st_shndx == SHN_ABS) |
| 892 | continue; |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 893 | |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 894 | sec = elf_getscn(runtime_ss->elf, sym.st_shndx); |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 895 | if (!sec) |
| 896 | goto out_elf_end; |
| 897 | |
| 898 | gelf_getshdr(sec, &shdr); |
| 899 | |
| 900 | if (is_label && !elf_sec__is_a(&shdr, secstrs, map->type)) |
| 901 | continue; |
| 902 | |
| 903 | section_name = elf_sec__name(&shdr, secstrs); |
| 904 | |
| 905 | /* On ARM, symbols for thumb functions have 1 added to |
| 906 | * the symbol address as a flag - remove it */ |
| 907 | if ((ehdr.e_machine == EM_ARM) && |
| 908 | (map->type == MAP__FUNCTION) && |
| 909 | (sym.st_value & 1)) |
| 910 | --sym.st_value; |
| 911 | |
Adrian Hunter | 39b12f78 | 2013-08-07 14:38:47 +0300 | [diff] [blame] | 912 | if (dso->kernel || kmodule) { |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 913 | char dso_name[PATH_MAX]; |
| 914 | |
Adrian Hunter | 39b12f78 | 2013-08-07 14:38:47 +0300 | [diff] [blame] | 915 | /* Adjust symbol to map to file offset */ |
| 916 | if (adjust_kernel_syms) |
| 917 | sym.st_value -= shdr.sh_addr - shdr.sh_offset; |
| 918 | |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 919 | if (strcmp(section_name, |
| 920 | (curr_dso->short_name + |
| 921 | dso->short_name_len)) == 0) |
| 922 | goto new_symbol; |
| 923 | |
| 924 | if (strcmp(section_name, ".text") == 0) { |
Adrian Hunter | 39b12f78 | 2013-08-07 14:38:47 +0300 | [diff] [blame] | 925 | /* |
| 926 | * The initial kernel mapping is based on |
| 927 | * kallsyms and identity maps. Overwrite it to |
| 928 | * map to the kernel dso. |
| 929 | */ |
| 930 | if (remap_kernel && dso->kernel) { |
| 931 | remap_kernel = false; |
| 932 | map->start = shdr.sh_addr + |
| 933 | ref_reloc(kmap); |
| 934 | map->end = map->start + shdr.sh_size; |
| 935 | map->pgoff = shdr.sh_offset; |
| 936 | map->map_ip = map__map_ip; |
| 937 | map->unmap_ip = map__unmap_ip; |
| 938 | /* Ensure maps are correctly ordered */ |
| 939 | map_groups__remove(kmap->kmaps, map); |
| 940 | map_groups__insert(kmap->kmaps, map); |
| 941 | } |
| 942 | |
Adrian Hunter | 0131c4e | 2013-08-07 14:38:50 +0300 | [diff] [blame] | 943 | /* |
| 944 | * The initial module mapping is based on |
| 945 | * /proc/modules mapped to offset zero. |
| 946 | * Overwrite it to map to the module dso. |
| 947 | */ |
| 948 | if (remap_kernel && kmodule) { |
| 949 | remap_kernel = false; |
| 950 | map->pgoff = shdr.sh_offset; |
| 951 | } |
| 952 | |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 953 | curr_map = map; |
| 954 | curr_dso = dso; |
| 955 | goto new_symbol; |
| 956 | } |
| 957 | |
Adrian Hunter | 0131c4e | 2013-08-07 14:38:50 +0300 | [diff] [blame] | 958 | if (!kmap) |
| 959 | goto new_symbol; |
| 960 | |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 961 | snprintf(dso_name, sizeof(dso_name), |
| 962 | "%s%s", dso->short_name, section_name); |
| 963 | |
| 964 | curr_map = map_groups__find_by_name(kmap->kmaps, map->type, dso_name); |
| 965 | if (curr_map == NULL) { |
| 966 | u64 start = sym.st_value; |
| 967 | |
| 968 | if (kmodule) |
| 969 | start += map->start + shdr.sh_offset; |
| 970 | |
| 971 | curr_dso = dso__new(dso_name); |
| 972 | if (curr_dso == NULL) |
| 973 | goto out_elf_end; |
| 974 | curr_dso->kernel = dso->kernel; |
| 975 | curr_dso->long_name = dso->long_name; |
| 976 | curr_dso->long_name_len = dso->long_name_len; |
| 977 | curr_map = map__new2(start, curr_dso, |
| 978 | map->type); |
| 979 | if (curr_map == NULL) { |
| 980 | dso__delete(curr_dso); |
| 981 | goto out_elf_end; |
| 982 | } |
Adrian Hunter | 39b12f78 | 2013-08-07 14:38:47 +0300 | [diff] [blame] | 983 | if (adjust_kernel_syms) { |
| 984 | curr_map->start = shdr.sh_addr + |
| 985 | ref_reloc(kmap); |
| 986 | curr_map->end = curr_map->start + |
| 987 | shdr.sh_size; |
| 988 | curr_map->pgoff = shdr.sh_offset; |
| 989 | } else { |
| 990 | curr_map->map_ip = identity__map_ip; |
| 991 | curr_map->unmap_ip = identity__map_ip; |
| 992 | } |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 993 | curr_dso->symtab_type = dso->symtab_type; |
| 994 | map_groups__insert(kmap->kmaps, curr_map); |
Waiman Long | 8fa7d87 | 2014-09-29 16:07:28 -0400 | [diff] [blame] | 995 | /* |
| 996 | * The new DSO should go to the kernel DSOS |
| 997 | */ |
| 998 | dsos__add(&map->groups->machine->kernel_dsos, |
| 999 | curr_dso); |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 1000 | dso__set_loaded(curr_dso, map->type); |
| 1001 | } else |
| 1002 | curr_dso = curr_map->dso; |
| 1003 | |
| 1004 | goto new_symbol; |
| 1005 | } |
| 1006 | |
Cody P Schafer | 261360b | 2012-08-10 15:23:01 -0700 | [diff] [blame] | 1007 | if ((used_opd && runtime_ss->adjust_symbols) |
| 1008 | || (!used_opd && syms_ss->adjust_symbols)) { |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 1009 | pr_debug4("%s: adjusting symbol: st_value: %#" PRIx64 " " |
| 1010 | "sh_addr: %#" PRIx64 " sh_offset: %#" PRIx64 "\n", __func__, |
| 1011 | (u64)sym.st_value, (u64)shdr.sh_addr, |
| 1012 | (u64)shdr.sh_offset); |
| 1013 | sym.st_value -= shdr.sh_addr - shdr.sh_offset; |
| 1014 | } |
Avi Kivity | 950b835 | 2014-01-22 21:58:46 +0200 | [diff] [blame] | 1015 | new_symbol: |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 1016 | /* |
| 1017 | * We need to figure out if the object was created from C++ sources |
| 1018 | * DWARF DW_compile_unit has this, but we don't always have access |
| 1019 | * to it... |
| 1020 | */ |
Avi Kivity | 763122a | 2014-09-13 07:15:05 +0300 | [diff] [blame] | 1021 | if (want_demangle(dso->kernel || kmodule)) { |
Namhyung Kim | e71e794 | 2014-07-31 14:47:42 +0900 | [diff] [blame] | 1022 | int demangle_flags = DMGL_NO_OPTS; |
| 1023 | if (verbose) |
| 1024 | demangle_flags = DMGL_PARAMS | DMGL_ANSI; |
| 1025 | |
| 1026 | demangled = bfd_demangle(NULL, elf_name, demangle_flags); |
Namhyung Kim | 328ccda | 2013-03-25 18:18:18 +0900 | [diff] [blame] | 1027 | if (demangled != NULL) |
| 1028 | elf_name = demangled; |
| 1029 | } |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 1030 | f = symbol__new(sym.st_value, sym.st_size, |
| 1031 | GELF_ST_BIND(sym.st_info), elf_name); |
| 1032 | free(demangled); |
| 1033 | if (!f) |
| 1034 | goto out_elf_end; |
| 1035 | |
| 1036 | if (filter && filter(curr_map, f)) |
| 1037 | symbol__delete(f); |
| 1038 | else { |
| 1039 | symbols__insert(&curr_dso->symbols[curr_map->type], f); |
| 1040 | nr++; |
| 1041 | } |
| 1042 | } |
| 1043 | |
| 1044 | /* |
| 1045 | * For misannotated, zeroed, ASM function sizes. |
| 1046 | */ |
| 1047 | if (nr > 0) { |
| 1048 | symbols__fixup_duplicate(&dso->symbols[map->type]); |
| 1049 | symbols__fixup_end(&dso->symbols[map->type]); |
| 1050 | if (kmap) { |
| 1051 | /* |
| 1052 | * We need to fixup this here too because we create new |
| 1053 | * maps here, for things like vsyscall sections. |
| 1054 | */ |
| 1055 | __map_groups__fixup_end(kmap->kmaps, map->type); |
| 1056 | } |
| 1057 | } |
| 1058 | err = nr; |
| 1059 | out_elf_end: |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 1060 | return err; |
| 1061 | } |
| 1062 | |
Adrian Hunter | 8e0cf96 | 2013-08-07 14:38:51 +0300 | [diff] [blame] | 1063 | static int elf_read_maps(Elf *elf, bool exe, mapfn_t mapfn, void *data) |
| 1064 | { |
| 1065 | GElf_Phdr phdr; |
| 1066 | size_t i, phdrnum; |
| 1067 | int err; |
| 1068 | u64 sz; |
| 1069 | |
| 1070 | if (elf_getphdrnum(elf, &phdrnum)) |
| 1071 | return -1; |
| 1072 | |
| 1073 | for (i = 0; i < phdrnum; i++) { |
| 1074 | if (gelf_getphdr(elf, i, &phdr) == NULL) |
| 1075 | return -1; |
| 1076 | if (phdr.p_type != PT_LOAD) |
| 1077 | continue; |
| 1078 | if (exe) { |
| 1079 | if (!(phdr.p_flags & PF_X)) |
| 1080 | continue; |
| 1081 | } else { |
| 1082 | if (!(phdr.p_flags & PF_R)) |
| 1083 | continue; |
| 1084 | } |
| 1085 | sz = min(phdr.p_memsz, phdr.p_filesz); |
| 1086 | if (!sz) |
| 1087 | continue; |
| 1088 | err = mapfn(phdr.p_vaddr, sz, phdr.p_offset, data); |
| 1089 | if (err) |
| 1090 | return err; |
| 1091 | } |
| 1092 | return 0; |
| 1093 | } |
| 1094 | |
| 1095 | int file__read_maps(int fd, bool exe, mapfn_t mapfn, void *data, |
| 1096 | bool *is_64_bit) |
| 1097 | { |
| 1098 | int err; |
| 1099 | Elf *elf; |
| 1100 | |
| 1101 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); |
| 1102 | if (elf == NULL) |
| 1103 | return -1; |
| 1104 | |
| 1105 | if (is_64_bit) |
| 1106 | *is_64_bit = (gelf_getclass(elf) == ELFCLASS64); |
| 1107 | |
| 1108 | err = elf_read_maps(elf, exe, mapfn, data); |
| 1109 | |
| 1110 | elf_end(elf); |
| 1111 | return err; |
| 1112 | } |
| 1113 | |
Adrian Hunter | 2b5b8bb | 2014-07-22 16:17:59 +0300 | [diff] [blame] | 1114 | enum dso_type dso__type_fd(int fd) |
| 1115 | { |
| 1116 | enum dso_type dso_type = DSO__TYPE_UNKNOWN; |
| 1117 | GElf_Ehdr ehdr; |
| 1118 | Elf_Kind ek; |
| 1119 | Elf *elf; |
| 1120 | |
| 1121 | elf = elf_begin(fd, PERF_ELF_C_READ_MMAP, NULL); |
| 1122 | if (elf == NULL) |
| 1123 | goto out; |
| 1124 | |
| 1125 | ek = elf_kind(elf); |
| 1126 | if (ek != ELF_K_ELF) |
| 1127 | goto out_end; |
| 1128 | |
| 1129 | if (gelf_getclass(elf) == ELFCLASS64) { |
| 1130 | dso_type = DSO__TYPE_64BIT; |
| 1131 | goto out_end; |
| 1132 | } |
| 1133 | |
| 1134 | if (gelf_getehdr(elf, &ehdr) == NULL) |
| 1135 | goto out_end; |
| 1136 | |
| 1137 | if (ehdr.e_machine == EM_X86_64) |
| 1138 | dso_type = DSO__TYPE_X32BIT; |
| 1139 | else |
| 1140 | dso_type = DSO__TYPE_32BIT; |
| 1141 | out_end: |
| 1142 | elf_end(elf); |
| 1143 | out: |
| 1144 | return dso_type; |
| 1145 | } |
| 1146 | |
Adrian Hunter | afba19d | 2013-10-09 15:01:12 +0300 | [diff] [blame] | 1147 | static int copy_bytes(int from, off_t from_offs, int to, off_t to_offs, u64 len) |
| 1148 | { |
| 1149 | ssize_t r; |
| 1150 | size_t n; |
| 1151 | int err = -1; |
| 1152 | char *buf = malloc(page_size); |
| 1153 | |
| 1154 | if (buf == NULL) |
| 1155 | return -1; |
| 1156 | |
| 1157 | if (lseek(to, to_offs, SEEK_SET) != to_offs) |
| 1158 | goto out; |
| 1159 | |
| 1160 | if (lseek(from, from_offs, SEEK_SET) != from_offs) |
| 1161 | goto out; |
| 1162 | |
| 1163 | while (len) { |
| 1164 | n = page_size; |
| 1165 | if (len < n) |
| 1166 | n = len; |
| 1167 | /* Use read because mmap won't work on proc files */ |
| 1168 | r = read(from, buf, n); |
| 1169 | if (r < 0) |
| 1170 | goto out; |
| 1171 | if (!r) |
| 1172 | break; |
| 1173 | n = r; |
| 1174 | r = write(to, buf, n); |
| 1175 | if (r < 0) |
| 1176 | goto out; |
| 1177 | if ((size_t)r != n) |
| 1178 | goto out; |
| 1179 | len -= n; |
| 1180 | } |
| 1181 | |
| 1182 | err = 0; |
| 1183 | out: |
| 1184 | free(buf); |
| 1185 | return err; |
| 1186 | } |
| 1187 | |
| 1188 | struct kcore { |
| 1189 | int fd; |
| 1190 | int elfclass; |
| 1191 | Elf *elf; |
| 1192 | GElf_Ehdr ehdr; |
| 1193 | }; |
| 1194 | |
| 1195 | static int kcore__open(struct kcore *kcore, const char *filename) |
| 1196 | { |
| 1197 | GElf_Ehdr *ehdr; |
| 1198 | |
| 1199 | kcore->fd = open(filename, O_RDONLY); |
| 1200 | if (kcore->fd == -1) |
| 1201 | return -1; |
| 1202 | |
| 1203 | kcore->elf = elf_begin(kcore->fd, ELF_C_READ, NULL); |
| 1204 | if (!kcore->elf) |
| 1205 | goto out_close; |
| 1206 | |
| 1207 | kcore->elfclass = gelf_getclass(kcore->elf); |
| 1208 | if (kcore->elfclass == ELFCLASSNONE) |
| 1209 | goto out_end; |
| 1210 | |
| 1211 | ehdr = gelf_getehdr(kcore->elf, &kcore->ehdr); |
| 1212 | if (!ehdr) |
| 1213 | goto out_end; |
| 1214 | |
| 1215 | return 0; |
| 1216 | |
| 1217 | out_end: |
| 1218 | elf_end(kcore->elf); |
| 1219 | out_close: |
| 1220 | close(kcore->fd); |
| 1221 | return -1; |
| 1222 | } |
| 1223 | |
| 1224 | static int kcore__init(struct kcore *kcore, char *filename, int elfclass, |
| 1225 | bool temp) |
| 1226 | { |
| 1227 | GElf_Ehdr *ehdr; |
| 1228 | |
| 1229 | kcore->elfclass = elfclass; |
| 1230 | |
| 1231 | if (temp) |
| 1232 | kcore->fd = mkstemp(filename); |
| 1233 | else |
| 1234 | kcore->fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, 0400); |
| 1235 | if (kcore->fd == -1) |
| 1236 | return -1; |
| 1237 | |
| 1238 | kcore->elf = elf_begin(kcore->fd, ELF_C_WRITE, NULL); |
| 1239 | if (!kcore->elf) |
| 1240 | goto out_close; |
| 1241 | |
| 1242 | if (!gelf_newehdr(kcore->elf, elfclass)) |
| 1243 | goto out_end; |
| 1244 | |
| 1245 | ehdr = gelf_getehdr(kcore->elf, &kcore->ehdr); |
| 1246 | if (!ehdr) |
| 1247 | goto out_end; |
| 1248 | |
| 1249 | return 0; |
| 1250 | |
| 1251 | out_end: |
| 1252 | elf_end(kcore->elf); |
| 1253 | out_close: |
| 1254 | close(kcore->fd); |
| 1255 | unlink(filename); |
| 1256 | return -1; |
| 1257 | } |
| 1258 | |
| 1259 | static void kcore__close(struct kcore *kcore) |
| 1260 | { |
| 1261 | elf_end(kcore->elf); |
| 1262 | close(kcore->fd); |
| 1263 | } |
| 1264 | |
| 1265 | static int kcore__copy_hdr(struct kcore *from, struct kcore *to, size_t count) |
| 1266 | { |
| 1267 | GElf_Ehdr *ehdr = &to->ehdr; |
| 1268 | GElf_Ehdr *kehdr = &from->ehdr; |
| 1269 | |
| 1270 | memcpy(ehdr->e_ident, kehdr->e_ident, EI_NIDENT); |
| 1271 | ehdr->e_type = kehdr->e_type; |
| 1272 | ehdr->e_machine = kehdr->e_machine; |
| 1273 | ehdr->e_version = kehdr->e_version; |
| 1274 | ehdr->e_entry = 0; |
| 1275 | ehdr->e_shoff = 0; |
| 1276 | ehdr->e_flags = kehdr->e_flags; |
| 1277 | ehdr->e_phnum = count; |
| 1278 | ehdr->e_shentsize = 0; |
| 1279 | ehdr->e_shnum = 0; |
| 1280 | ehdr->e_shstrndx = 0; |
| 1281 | |
| 1282 | if (from->elfclass == ELFCLASS32) { |
| 1283 | ehdr->e_phoff = sizeof(Elf32_Ehdr); |
| 1284 | ehdr->e_ehsize = sizeof(Elf32_Ehdr); |
| 1285 | ehdr->e_phentsize = sizeof(Elf32_Phdr); |
| 1286 | } else { |
| 1287 | ehdr->e_phoff = sizeof(Elf64_Ehdr); |
| 1288 | ehdr->e_ehsize = sizeof(Elf64_Ehdr); |
| 1289 | ehdr->e_phentsize = sizeof(Elf64_Phdr); |
| 1290 | } |
| 1291 | |
| 1292 | if (!gelf_update_ehdr(to->elf, ehdr)) |
| 1293 | return -1; |
| 1294 | |
| 1295 | if (!gelf_newphdr(to->elf, count)) |
| 1296 | return -1; |
| 1297 | |
| 1298 | return 0; |
| 1299 | } |
| 1300 | |
| 1301 | static int kcore__add_phdr(struct kcore *kcore, int idx, off_t offset, |
| 1302 | u64 addr, u64 len) |
| 1303 | { |
| 1304 | GElf_Phdr gphdr; |
| 1305 | GElf_Phdr *phdr; |
| 1306 | |
| 1307 | phdr = gelf_getphdr(kcore->elf, idx, &gphdr); |
| 1308 | if (!phdr) |
| 1309 | return -1; |
| 1310 | |
| 1311 | phdr->p_type = PT_LOAD; |
| 1312 | phdr->p_flags = PF_R | PF_W | PF_X; |
| 1313 | phdr->p_offset = offset; |
| 1314 | phdr->p_vaddr = addr; |
| 1315 | phdr->p_paddr = 0; |
| 1316 | phdr->p_filesz = len; |
| 1317 | phdr->p_memsz = len; |
| 1318 | phdr->p_align = page_size; |
| 1319 | |
| 1320 | if (!gelf_update_phdr(kcore->elf, idx, phdr)) |
| 1321 | return -1; |
| 1322 | |
| 1323 | return 0; |
| 1324 | } |
| 1325 | |
| 1326 | static off_t kcore__write(struct kcore *kcore) |
| 1327 | { |
| 1328 | return elf_update(kcore->elf, ELF_C_WRITE); |
| 1329 | } |
| 1330 | |
Adrian Hunter | fc1b691 | 2013-10-14 16:57:29 +0300 | [diff] [blame] | 1331 | struct phdr_data { |
| 1332 | off_t offset; |
| 1333 | u64 addr; |
| 1334 | u64 len; |
| 1335 | }; |
| 1336 | |
| 1337 | struct kcore_copy_info { |
| 1338 | u64 stext; |
| 1339 | u64 etext; |
| 1340 | u64 first_symbol; |
| 1341 | u64 last_symbol; |
| 1342 | u64 first_module; |
| 1343 | u64 last_module_symbol; |
| 1344 | struct phdr_data kernel_map; |
| 1345 | struct phdr_data modules_map; |
| 1346 | }; |
| 1347 | |
| 1348 | static int kcore_copy__process_kallsyms(void *arg, const char *name, char type, |
| 1349 | u64 start) |
| 1350 | { |
| 1351 | struct kcore_copy_info *kci = arg; |
| 1352 | |
| 1353 | if (!symbol_type__is_a(type, MAP__FUNCTION)) |
| 1354 | return 0; |
| 1355 | |
| 1356 | if (strchr(name, '[')) { |
| 1357 | if (start > kci->last_module_symbol) |
| 1358 | kci->last_module_symbol = start; |
| 1359 | return 0; |
| 1360 | } |
| 1361 | |
| 1362 | if (!kci->first_symbol || start < kci->first_symbol) |
| 1363 | kci->first_symbol = start; |
| 1364 | |
| 1365 | if (!kci->last_symbol || start > kci->last_symbol) |
| 1366 | kci->last_symbol = start; |
| 1367 | |
| 1368 | if (!strcmp(name, "_stext")) { |
| 1369 | kci->stext = start; |
| 1370 | return 0; |
| 1371 | } |
| 1372 | |
| 1373 | if (!strcmp(name, "_etext")) { |
| 1374 | kci->etext = start; |
| 1375 | return 0; |
| 1376 | } |
| 1377 | |
| 1378 | return 0; |
| 1379 | } |
| 1380 | |
| 1381 | static int kcore_copy__parse_kallsyms(struct kcore_copy_info *kci, |
| 1382 | const char *dir) |
| 1383 | { |
| 1384 | char kallsyms_filename[PATH_MAX]; |
| 1385 | |
| 1386 | scnprintf(kallsyms_filename, PATH_MAX, "%s/kallsyms", dir); |
| 1387 | |
| 1388 | if (symbol__restricted_filename(kallsyms_filename, "/proc/kallsyms")) |
| 1389 | return -1; |
| 1390 | |
| 1391 | if (kallsyms__parse(kallsyms_filename, kci, |
| 1392 | kcore_copy__process_kallsyms) < 0) |
| 1393 | return -1; |
| 1394 | |
| 1395 | return 0; |
| 1396 | } |
| 1397 | |
| 1398 | static int kcore_copy__process_modules(void *arg, |
| 1399 | const char *name __maybe_unused, |
| 1400 | u64 start) |
| 1401 | { |
| 1402 | struct kcore_copy_info *kci = arg; |
| 1403 | |
| 1404 | if (!kci->first_module || start < kci->first_module) |
| 1405 | kci->first_module = start; |
| 1406 | |
| 1407 | return 0; |
| 1408 | } |
| 1409 | |
| 1410 | static int kcore_copy__parse_modules(struct kcore_copy_info *kci, |
| 1411 | const char *dir) |
| 1412 | { |
| 1413 | char modules_filename[PATH_MAX]; |
| 1414 | |
| 1415 | scnprintf(modules_filename, PATH_MAX, "%s/modules", dir); |
| 1416 | |
| 1417 | if (symbol__restricted_filename(modules_filename, "/proc/modules")) |
| 1418 | return -1; |
| 1419 | |
| 1420 | if (modules__parse(modules_filename, kci, |
| 1421 | kcore_copy__process_modules) < 0) |
| 1422 | return -1; |
| 1423 | |
| 1424 | return 0; |
| 1425 | } |
| 1426 | |
| 1427 | static void kcore_copy__map(struct phdr_data *p, u64 start, u64 end, u64 pgoff, |
| 1428 | u64 s, u64 e) |
| 1429 | { |
| 1430 | if (p->addr || s < start || s >= end) |
| 1431 | return; |
| 1432 | |
| 1433 | p->addr = s; |
| 1434 | p->offset = (s - start) + pgoff; |
| 1435 | p->len = e < end ? e - s : end - s; |
| 1436 | } |
| 1437 | |
| 1438 | static int kcore_copy__read_map(u64 start, u64 len, u64 pgoff, void *data) |
| 1439 | { |
| 1440 | struct kcore_copy_info *kci = data; |
| 1441 | u64 end = start + len; |
| 1442 | |
| 1443 | kcore_copy__map(&kci->kernel_map, start, end, pgoff, kci->stext, |
| 1444 | kci->etext); |
| 1445 | |
| 1446 | kcore_copy__map(&kci->modules_map, start, end, pgoff, kci->first_module, |
| 1447 | kci->last_module_symbol); |
| 1448 | |
| 1449 | return 0; |
| 1450 | } |
| 1451 | |
| 1452 | static int kcore_copy__read_maps(struct kcore_copy_info *kci, Elf *elf) |
| 1453 | { |
| 1454 | if (elf_read_maps(elf, true, kcore_copy__read_map, kci) < 0) |
| 1455 | return -1; |
| 1456 | |
| 1457 | return 0; |
| 1458 | } |
| 1459 | |
| 1460 | static int kcore_copy__calc_maps(struct kcore_copy_info *kci, const char *dir, |
| 1461 | Elf *elf) |
| 1462 | { |
| 1463 | if (kcore_copy__parse_kallsyms(kci, dir)) |
| 1464 | return -1; |
| 1465 | |
| 1466 | if (kcore_copy__parse_modules(kci, dir)) |
| 1467 | return -1; |
| 1468 | |
| 1469 | if (kci->stext) |
| 1470 | kci->stext = round_down(kci->stext, page_size); |
| 1471 | else |
| 1472 | kci->stext = round_down(kci->first_symbol, page_size); |
| 1473 | |
| 1474 | if (kci->etext) { |
| 1475 | kci->etext = round_up(kci->etext, page_size); |
| 1476 | } else if (kci->last_symbol) { |
| 1477 | kci->etext = round_up(kci->last_symbol, page_size); |
| 1478 | kci->etext += page_size; |
| 1479 | } |
| 1480 | |
| 1481 | kci->first_module = round_down(kci->first_module, page_size); |
| 1482 | |
| 1483 | if (kci->last_module_symbol) { |
| 1484 | kci->last_module_symbol = round_up(kci->last_module_symbol, |
| 1485 | page_size); |
| 1486 | kci->last_module_symbol += page_size; |
| 1487 | } |
| 1488 | |
| 1489 | if (!kci->stext || !kci->etext) |
| 1490 | return -1; |
| 1491 | |
| 1492 | if (kci->first_module && !kci->last_module_symbol) |
| 1493 | return -1; |
| 1494 | |
| 1495 | return kcore_copy__read_maps(kci, elf); |
| 1496 | } |
| 1497 | |
| 1498 | static int kcore_copy__copy_file(const char *from_dir, const char *to_dir, |
| 1499 | const char *name) |
| 1500 | { |
| 1501 | char from_filename[PATH_MAX]; |
| 1502 | char to_filename[PATH_MAX]; |
| 1503 | |
| 1504 | scnprintf(from_filename, PATH_MAX, "%s/%s", from_dir, name); |
| 1505 | scnprintf(to_filename, PATH_MAX, "%s/%s", to_dir, name); |
| 1506 | |
| 1507 | return copyfile_mode(from_filename, to_filename, 0400); |
| 1508 | } |
| 1509 | |
| 1510 | static int kcore_copy__unlink(const char *dir, const char *name) |
| 1511 | { |
| 1512 | char filename[PATH_MAX]; |
| 1513 | |
| 1514 | scnprintf(filename, PATH_MAX, "%s/%s", dir, name); |
| 1515 | |
| 1516 | return unlink(filename); |
| 1517 | } |
| 1518 | |
| 1519 | static int kcore_copy__compare_fds(int from, int to) |
| 1520 | { |
| 1521 | char *buf_from; |
| 1522 | char *buf_to; |
| 1523 | ssize_t ret; |
| 1524 | size_t len; |
| 1525 | int err = -1; |
| 1526 | |
| 1527 | buf_from = malloc(page_size); |
| 1528 | buf_to = malloc(page_size); |
| 1529 | if (!buf_from || !buf_to) |
| 1530 | goto out; |
| 1531 | |
| 1532 | while (1) { |
| 1533 | /* Use read because mmap won't work on proc files */ |
| 1534 | ret = read(from, buf_from, page_size); |
| 1535 | if (ret < 0) |
| 1536 | goto out; |
| 1537 | |
| 1538 | if (!ret) |
| 1539 | break; |
| 1540 | |
| 1541 | len = ret; |
| 1542 | |
| 1543 | if (readn(to, buf_to, len) != (int)len) |
| 1544 | goto out; |
| 1545 | |
| 1546 | if (memcmp(buf_from, buf_to, len)) |
| 1547 | goto out; |
| 1548 | } |
| 1549 | |
| 1550 | err = 0; |
| 1551 | out: |
| 1552 | free(buf_to); |
| 1553 | free(buf_from); |
| 1554 | return err; |
| 1555 | } |
| 1556 | |
| 1557 | static int kcore_copy__compare_files(const char *from_filename, |
| 1558 | const char *to_filename) |
| 1559 | { |
| 1560 | int from, to, err = -1; |
| 1561 | |
| 1562 | from = open(from_filename, O_RDONLY); |
| 1563 | if (from < 0) |
| 1564 | return -1; |
| 1565 | |
| 1566 | to = open(to_filename, O_RDONLY); |
| 1567 | if (to < 0) |
| 1568 | goto out_close_from; |
| 1569 | |
| 1570 | err = kcore_copy__compare_fds(from, to); |
| 1571 | |
| 1572 | close(to); |
| 1573 | out_close_from: |
| 1574 | close(from); |
| 1575 | return err; |
| 1576 | } |
| 1577 | |
| 1578 | static int kcore_copy__compare_file(const char *from_dir, const char *to_dir, |
| 1579 | const char *name) |
| 1580 | { |
| 1581 | char from_filename[PATH_MAX]; |
| 1582 | char to_filename[PATH_MAX]; |
| 1583 | |
| 1584 | scnprintf(from_filename, PATH_MAX, "%s/%s", from_dir, name); |
| 1585 | scnprintf(to_filename, PATH_MAX, "%s/%s", to_dir, name); |
| 1586 | |
| 1587 | return kcore_copy__compare_files(from_filename, to_filename); |
| 1588 | } |
| 1589 | |
| 1590 | /** |
| 1591 | * kcore_copy - copy kallsyms, modules and kcore from one directory to another. |
| 1592 | * @from_dir: from directory |
| 1593 | * @to_dir: to directory |
| 1594 | * |
| 1595 | * This function copies kallsyms, modules and kcore files from one directory to |
| 1596 | * another. kallsyms and modules are copied entirely. Only code segments are |
| 1597 | * copied from kcore. It is assumed that two segments suffice: one for the |
| 1598 | * kernel proper and one for all the modules. The code segments are determined |
| 1599 | * from kallsyms and modules files. The kernel map starts at _stext or the |
| 1600 | * lowest function symbol, and ends at _etext or the highest function symbol. |
| 1601 | * The module map starts at the lowest module address and ends at the highest |
| 1602 | * module symbol. Start addresses are rounded down to the nearest page. End |
| 1603 | * addresses are rounded up to the nearest page. An extra page is added to the |
| 1604 | * highest kernel symbol and highest module symbol to, hopefully, encompass that |
| 1605 | * symbol too. Because it contains only code sections, the resulting kcore is |
| 1606 | * unusual. One significant peculiarity is that the mapping (start -> pgoff) |
| 1607 | * is not the same for the kernel map and the modules map. That happens because |
| 1608 | * the data is copied adjacently whereas the original kcore has gaps. Finally, |
| 1609 | * kallsyms and modules files are compared with their copies to check that |
| 1610 | * modules have not been loaded or unloaded while the copies were taking place. |
| 1611 | * |
| 1612 | * Return: %0 on success, %-1 on failure. |
| 1613 | */ |
| 1614 | int kcore_copy(const char *from_dir, const char *to_dir) |
| 1615 | { |
| 1616 | struct kcore kcore; |
| 1617 | struct kcore extract; |
| 1618 | size_t count = 2; |
| 1619 | int idx = 0, err = -1; |
| 1620 | off_t offset = page_size, sz, modules_offset = 0; |
| 1621 | struct kcore_copy_info kci = { .stext = 0, }; |
| 1622 | char kcore_filename[PATH_MAX]; |
| 1623 | char extract_filename[PATH_MAX]; |
| 1624 | |
| 1625 | if (kcore_copy__copy_file(from_dir, to_dir, "kallsyms")) |
| 1626 | return -1; |
| 1627 | |
| 1628 | if (kcore_copy__copy_file(from_dir, to_dir, "modules")) |
| 1629 | goto out_unlink_kallsyms; |
| 1630 | |
| 1631 | scnprintf(kcore_filename, PATH_MAX, "%s/kcore", from_dir); |
| 1632 | scnprintf(extract_filename, PATH_MAX, "%s/kcore", to_dir); |
| 1633 | |
| 1634 | if (kcore__open(&kcore, kcore_filename)) |
| 1635 | goto out_unlink_modules; |
| 1636 | |
| 1637 | if (kcore_copy__calc_maps(&kci, from_dir, kcore.elf)) |
| 1638 | goto out_kcore_close; |
| 1639 | |
| 1640 | if (kcore__init(&extract, extract_filename, kcore.elfclass, false)) |
| 1641 | goto out_kcore_close; |
| 1642 | |
| 1643 | if (!kci.modules_map.addr) |
| 1644 | count -= 1; |
| 1645 | |
| 1646 | if (kcore__copy_hdr(&kcore, &extract, count)) |
| 1647 | goto out_extract_close; |
| 1648 | |
| 1649 | if (kcore__add_phdr(&extract, idx++, offset, kci.kernel_map.addr, |
| 1650 | kci.kernel_map.len)) |
| 1651 | goto out_extract_close; |
| 1652 | |
| 1653 | if (kci.modules_map.addr) { |
| 1654 | modules_offset = offset + kci.kernel_map.len; |
| 1655 | if (kcore__add_phdr(&extract, idx, modules_offset, |
| 1656 | kci.modules_map.addr, kci.modules_map.len)) |
| 1657 | goto out_extract_close; |
| 1658 | } |
| 1659 | |
| 1660 | sz = kcore__write(&extract); |
| 1661 | if (sz < 0 || sz > offset) |
| 1662 | goto out_extract_close; |
| 1663 | |
| 1664 | if (copy_bytes(kcore.fd, kci.kernel_map.offset, extract.fd, offset, |
| 1665 | kci.kernel_map.len)) |
| 1666 | goto out_extract_close; |
| 1667 | |
| 1668 | if (modules_offset && copy_bytes(kcore.fd, kci.modules_map.offset, |
| 1669 | extract.fd, modules_offset, |
| 1670 | kci.modules_map.len)) |
| 1671 | goto out_extract_close; |
| 1672 | |
| 1673 | if (kcore_copy__compare_file(from_dir, to_dir, "modules")) |
| 1674 | goto out_extract_close; |
| 1675 | |
| 1676 | if (kcore_copy__compare_file(from_dir, to_dir, "kallsyms")) |
| 1677 | goto out_extract_close; |
| 1678 | |
| 1679 | err = 0; |
| 1680 | |
| 1681 | out_extract_close: |
| 1682 | kcore__close(&extract); |
| 1683 | if (err) |
| 1684 | unlink(extract_filename); |
| 1685 | out_kcore_close: |
| 1686 | kcore__close(&kcore); |
| 1687 | out_unlink_modules: |
| 1688 | if (err) |
| 1689 | kcore_copy__unlink(to_dir, "modules"); |
| 1690 | out_unlink_kallsyms: |
| 1691 | if (err) |
| 1692 | kcore_copy__unlink(to_dir, "kallsyms"); |
| 1693 | |
| 1694 | return err; |
| 1695 | } |
| 1696 | |
Adrian Hunter | afba19d | 2013-10-09 15:01:12 +0300 | [diff] [blame] | 1697 | int kcore_extract__create(struct kcore_extract *kce) |
| 1698 | { |
| 1699 | struct kcore kcore; |
| 1700 | struct kcore extract; |
| 1701 | size_t count = 1; |
| 1702 | int idx = 0, err = -1; |
| 1703 | off_t offset = page_size, sz; |
| 1704 | |
| 1705 | if (kcore__open(&kcore, kce->kcore_filename)) |
| 1706 | return -1; |
| 1707 | |
| 1708 | strcpy(kce->extract_filename, PERF_KCORE_EXTRACT); |
| 1709 | if (kcore__init(&extract, kce->extract_filename, kcore.elfclass, true)) |
| 1710 | goto out_kcore_close; |
| 1711 | |
| 1712 | if (kcore__copy_hdr(&kcore, &extract, count)) |
| 1713 | goto out_extract_close; |
| 1714 | |
| 1715 | if (kcore__add_phdr(&extract, idx, offset, kce->addr, kce->len)) |
| 1716 | goto out_extract_close; |
| 1717 | |
| 1718 | sz = kcore__write(&extract); |
| 1719 | if (sz < 0 || sz > offset) |
| 1720 | goto out_extract_close; |
| 1721 | |
| 1722 | if (copy_bytes(kcore.fd, kce->offs, extract.fd, offset, kce->len)) |
| 1723 | goto out_extract_close; |
| 1724 | |
| 1725 | err = 0; |
| 1726 | |
| 1727 | out_extract_close: |
| 1728 | kcore__close(&extract); |
| 1729 | if (err) |
| 1730 | unlink(kce->extract_filename); |
| 1731 | out_kcore_close: |
| 1732 | kcore__close(&kcore); |
| 1733 | |
| 1734 | return err; |
| 1735 | } |
| 1736 | |
| 1737 | void kcore_extract__delete(struct kcore_extract *kce) |
| 1738 | { |
| 1739 | unlink(kce->extract_filename); |
| 1740 | } |
| 1741 | |
Namhyung Kim | e5a1845 | 2012-08-06 13:41:20 +0900 | [diff] [blame] | 1742 | void symbol__elf_init(void) |
| 1743 | { |
| 1744 | elf_version(EV_CURRENT); |
| 1745 | } |