Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* Generate assembler source containing symbol information |
2 | * | |
3 | * Copyright 2002 by Kai Germaschewski | |
4 | * | |
5 | * This software may be used and distributed according to the terms | |
6 | * of the GNU General Public License, incorporated herein by reference. | |
7 | * | |
adc40221 YU |
8 | * Usage: kallsyms [--all-symbols] [--absolute-percpu] |
9 | * [--base-relative] in.map > out.S | |
1da177e4 | 10 | * |
1da177e4 LT |
11 | * Table compression uses all the unused char codes on the symbols and |
12 | * maps these to the most used substrings (tokens). For instance, it might | |
13 | * map char code 0xF7 to represent "write_" and then in every symbol where | |
14 | * "write_" appears it can be replaced by 0xF7, saving 5 bytes. | |
15 | * The used codes themselves are also placed in the table so that the | |
16 | * decompresion can work without "special cases". | |
17 | * Applied to kernel symbols, this usually produces a compression ratio | |
18 | * of about 50%. | |
19 | * | |
20 | */ | |
21 | ||
aa221f2e | 22 | #include <getopt.h> |
a41333e0 | 23 | #include <stdbool.h> |
1da177e4 LT |
24 | #include <stdio.h> |
25 | #include <stdlib.h> | |
26 | #include <string.h> | |
27 | #include <ctype.h> | |
2213e9a6 | 28 | #include <limits.h> |
1da177e4 | 29 | |
17b1f0de | 30 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0])) |
17b1f0de | 31 | |
b471927e BF |
32 | #define _stringify_1(x) #x |
33 | #define _stringify(x) _stringify_1(x) | |
34 | ||
b8a94bfb | 35 | #define KSYM_NAME_LEN 512 |
1da177e4 | 36 | |
6e8c5bbd MO |
37 | /* |
38 | * A substantially bigger size than the current maximum. | |
39 | * | |
40 | * It cannot be defined as an expression because it gets stringified | |
41 | * for the fscanf() format string. Therefore, a _Static_assert() is | |
42 | * used instead to maintain the relationship with KSYM_NAME_LEN. | |
43 | */ | |
b8a94bfb | 44 | #define KSYM_NAME_LEN_BUFFER 2048 |
6e8c5bbd MO |
45 | _Static_assert( |
46 | KSYM_NAME_LEN_BUFFER == KSYM_NAME_LEN * 4, | |
47 | "Please keep KSYM_NAME_LEN_BUFFER in sync with KSYM_NAME_LEN" | |
48 | ); | |
b471927e | 49 | |
1da177e4 LT |
50 | struct sym_entry { |
51 | unsigned long long addr; | |
b3dbb4ec | 52 | unsigned int len; |
60443c88 | 53 | unsigned int seq; |
f2df3f65 | 54 | unsigned int start_pos; |
8c996940 | 55 | unsigned int percpu_absolute; |
9d82973e | 56 | unsigned char sym[]; |
1da177e4 LT |
57 | }; |
58 | ||
78eb7159 KC |
59 | struct addr_range { |
60 | const char *start_sym, *end_sym; | |
17b1f0de MF |
61 | unsigned long long start, end; |
62 | }; | |
63 | ||
64 | static unsigned long long _text; | |
2213e9a6 | 65 | static unsigned long long relative_base; |
78eb7159 | 66 | static struct addr_range text_ranges[] = { |
17b1f0de MF |
67 | { "_stext", "_etext" }, |
68 | { "_sinittext", "_einittext" }, | |
17b1f0de MF |
69 | }; |
70 | #define text_range_text (&text_ranges[0]) | |
71 | #define text_range_inittext (&text_ranges[1]) | |
72 | ||
c6bda7c9 RR |
73 | static struct addr_range percpu_range = { |
74 | "__per_cpu_start", "__per_cpu_end", -1ULL, 0 | |
75 | }; | |
76 | ||
8d605269 | 77 | static struct sym_entry **table; |
b3dbb4ec | 78 | static unsigned int table_size, table_cnt; |
831362fc MY |
79 | static int all_symbols; |
80 | static int absolute_percpu; | |
81 | static int base_relative; | |
010a0aad | 82 | static int lto_clang; |
1da177e4 | 83 | |
f43e9daa | 84 | static int token_profit[0x10000]; |
1da177e4 LT |
85 | |
86 | /* the table that holds the result of the compression */ | |
f43e9daa MY |
87 | static unsigned char best_table[256][2]; |
88 | static unsigned char best_table_len[256]; | |
1da177e4 LT |
89 | |
90 | ||
b3dbb4ec | 91 | static void usage(void) |
1da177e4 | 92 | { |
8d3a7507 | 93 | fprintf(stderr, "Usage: kallsyms [--all-symbols] [--absolute-percpu] " |
010a0aad | 94 | "[--base-relative] [--lto-clang] in.map > out.S\n"); |
1da177e4 LT |
95 | exit(1); |
96 | } | |
97 | ||
29e55ad3 MY |
98 | static char *sym_name(const struct sym_entry *s) |
99 | { | |
100 | return (char *)s->sym + 1; | |
101 | } | |
102 | ||
a41333e0 MY |
103 | static bool is_ignored_symbol(const char *name, char type) |
104 | { | |
516d980f | 105 | /* Symbol names that exactly match to the following are ignored.*/ |
a41333e0 MY |
106 | static const char * const ignored_symbols[] = { |
107 | /* | |
108 | * Symbols which vary between passes. Passes 1 and 2 must have | |
109 | * identical symbol lists. The kallsyms_* symbols below are | |
110 | * only added after pass 1, they would be included in pass 2 | |
111 | * when --all-symbols is specified so exclude them to get a | |
112 | * stable symbol list. | |
113 | */ | |
114 | "kallsyms_addresses", | |
115 | "kallsyms_offsets", | |
116 | "kallsyms_relative_base", | |
117 | "kallsyms_num_syms", | |
118 | "kallsyms_names", | |
119 | "kallsyms_markers", | |
120 | "kallsyms_token_table", | |
121 | "kallsyms_token_index", | |
122 | /* Exclude linker generated symbols which vary between passes */ | |
123 | "_SDA_BASE_", /* ppc */ | |
124 | "_SDA2_BASE_", /* ppc */ | |
125 | NULL | |
126 | }; | |
127 | ||
516d980f | 128 | /* Symbol names that begin with the following are ignored.*/ |
a41333e0 | 129 | static const char * const ignored_prefixes[] = { |
a41333e0 | 130 | "__efistub_", /* arm64 EFI stub namespace */ |
6ccf9cb5 KS |
131 | "__kvm_nvhe_$", /* arm64 local symbols in non-VHE KVM namespace */ |
132 | "__kvm_nvhe_.L", /* arm64 local symbols in non-VHE KVM namespace */ | |
efe6e306 AB |
133 | "__AArch64ADRPThunk_", /* arm64 lld */ |
134 | "__ARMV5PILongThunk_", /* arm lld */ | |
135 | "__ARMV7PILongThunk_", | |
136 | "__ThumbV7PILongThunk_", | |
137 | "__LA25Thunk_", /* mips lld */ | |
138 | "__microLA25Thunk_", | |
d0f9562e | 139 | "__kcfi_typeid_", /* CFI type identifiers */ |
a41333e0 MY |
140 | NULL |
141 | }; | |
142 | ||
516d980f | 143 | /* Symbol names that end with the following are ignored.*/ |
a41333e0 MY |
144 | static const char * const ignored_suffixes[] = { |
145 | "_from_arm", /* arm */ | |
146 | "_from_thumb", /* arm */ | |
147 | "_veneer", /* arm */ | |
148 | NULL | |
149 | }; | |
150 | ||
516d980f MY |
151 | /* Symbol names that contain the following are ignored.*/ |
152 | static const char * const ignored_matches[] = { | |
153 | ".long_branch.", /* ppc stub */ | |
154 | ".plt_branch.", /* ppc stub */ | |
155 | NULL | |
156 | }; | |
157 | ||
a41333e0 MY |
158 | const char * const *p; |
159 | ||
a41333e0 MY |
160 | for (p = ignored_symbols; *p; p++) |
161 | if (!strcmp(name, *p)) | |
162 | return true; | |
163 | ||
164 | for (p = ignored_prefixes; *p; p++) | |
165 | if (!strncmp(name, *p, strlen(*p))) | |
166 | return true; | |
167 | ||
168 | for (p = ignored_suffixes; *p; p++) { | |
169 | int l = strlen(name) - strlen(*p); | |
170 | ||
171 | if (l >= 0 && !strcmp(name + l, *p)) | |
172 | return true; | |
173 | } | |
174 | ||
516d980f MY |
175 | for (p = ignored_matches; *p; p++) { |
176 | if (strstr(name, *p)) | |
177 | return true; | |
178 | } | |
179 | ||
887df76d MY |
180 | if (type == 'U' || type == 'u') |
181 | return true; | |
182 | /* exclude debugging symbols */ | |
183 | if (type == 'N' || type == 'n') | |
184 | return true; | |
185 | ||
186 | if (toupper(type) == 'A') { | |
187 | /* Keep these useful absolute symbols */ | |
188 | if (strcmp(name, "__kernel_syscall_via_break") && | |
189 | strcmp(name, "__kernel_syscall_via_epc") && | |
190 | strcmp(name, "__kernel_sigtramp") && | |
191 | strcmp(name, "__gp")) | |
192 | return true; | |
193 | } | |
194 | ||
a41333e0 MY |
195 | return false; |
196 | } | |
197 | ||
b6233d0d MY |
198 | static void check_symbol_range(const char *sym, unsigned long long addr, |
199 | struct addr_range *ranges, int entries) | |
17b1f0de MF |
200 | { |
201 | size_t i; | |
78eb7159 | 202 | struct addr_range *ar; |
17b1f0de | 203 | |
78eb7159 KC |
204 | for (i = 0; i < entries; ++i) { |
205 | ar = &ranges[i]; | |
17b1f0de | 206 | |
78eb7159 KC |
207 | if (strcmp(sym, ar->start_sym) == 0) { |
208 | ar->start = addr; | |
b6233d0d | 209 | return; |
78eb7159 KC |
210 | } else if (strcmp(sym, ar->end_sym) == 0) { |
211 | ar->end = addr; | |
b6233d0d | 212 | return; |
17b1f0de MF |
213 | } |
214 | } | |
17b1f0de MF |
215 | } |
216 | ||
8d605269 | 217 | static struct sym_entry *read_symbol(FILE *in) |
1da177e4 | 218 | { |
b471927e | 219 | char name[KSYM_NAME_LEN_BUFFER+1], type; |
8d605269 MY |
220 | unsigned long long addr; |
221 | unsigned int len; | |
222 | struct sym_entry *sym; | |
1da177e4 LT |
223 | int rc; |
224 | ||
b471927e | 225 | rc = fscanf(in, "%llx %c %" _stringify(KSYM_NAME_LEN_BUFFER) "s\n", &addr, &type, name); |
1da177e4 | 226 | if (rc != 3) { |
b66c874f | 227 | if (rc != EOF && fgets(name, ARRAY_SIZE(name), in) == NULL) |
ef894870 | 228 | fprintf(stderr, "Read error or end of file.\n"); |
8d605269 | 229 | return NULL; |
1da177e4 | 230 | } |
be9f6133 | 231 | if (strlen(name) >= KSYM_NAME_LEN) { |
6db2983c | 232 | fprintf(stderr, "Symbol %s too long for kallsyms (%zu >= %d).\n" |
bb66fc67 | 233 | "Please increase KSYM_NAME_LEN both in kernel and kallsyms.c\n", |
be9f6133 | 234 | name, strlen(name), KSYM_NAME_LEN); |
8d605269 | 235 | return NULL; |
f3462aa9 | 236 | } |
1da177e4 | 237 | |
be9f6133 | 238 | if (strcmp(name, "_text") == 0) |
8d605269 | 239 | _text = addr; |
b6233d0d | 240 | |
7883a143 MP |
241 | /* Ignore most absolute/undefined (?) symbols. */ |
242 | if (is_ignored_symbol(name, type)) | |
243 | return NULL; | |
244 | ||
8d605269 MY |
245 | check_symbol_range(name, addr, text_ranges, ARRAY_SIZE(text_ranges)); |
246 | check_symbol_range(name, addr, &percpu_range, 1); | |
1da177e4 LT |
247 | |
248 | /* include the type field in the symbol name, so that it gets | |
249 | * compressed together */ | |
8d605269 MY |
250 | |
251 | len = strlen(name) + 1; | |
252 | ||
9d1b3895 | 253 | sym = malloc(sizeof(*sym) + len + 1); |
8d605269 | 254 | if (!sym) { |
f1a136e0 JJ |
255 | fprintf(stderr, "kallsyms failure: " |
256 | "unable to allocate required amount of memory\n"); | |
257 | exit(EXIT_FAILURE); | |
258 | } | |
8d605269 MY |
259 | sym->addr = addr; |
260 | sym->len = len; | |
261 | sym->sym[0] = type; | |
9d1b3895 | 262 | strcpy(sym_name(sym), name); |
8d605269 | 263 | sym->percpu_absolute = 0; |
8c996940 | 264 | |
8d605269 | 265 | return sym; |
1da177e4 LT |
266 | } |
267 | ||
4bfe2b78 MY |
268 | static int symbol_in_range(const struct sym_entry *s, |
269 | const struct addr_range *ranges, int entries) | |
17b1f0de MF |
270 | { |
271 | size_t i; | |
4bfe2b78 | 272 | const struct addr_range *ar; |
17b1f0de | 273 | |
78eb7159 KC |
274 | for (i = 0; i < entries; ++i) { |
275 | ar = &ranges[i]; | |
17b1f0de | 276 | |
78eb7159 | 277 | if (s->addr >= ar->start && s->addr <= ar->end) |
ac6ca5c8 | 278 | return 1; |
17b1f0de MF |
279 | } |
280 | ||
ac6ca5c8 | 281 | return 0; |
17b1f0de MF |
282 | } |
283 | ||
4bfe2b78 | 284 | static int symbol_valid(const struct sym_entry *s) |
1da177e4 | 285 | { |
29e55ad3 | 286 | const char *name = sym_name(s); |
bd8b22d2 | 287 | |
1da177e4 LT |
288 | /* if --all-symbols is not specified, then symbols outside the text |
289 | * and inittext sections are discarded */ | |
290 | if (!all_symbols) { | |
78eb7159 KC |
291 | if (symbol_in_range(s, text_ranges, |
292 | ARRAY_SIZE(text_ranges)) == 0) | |
1da177e4 LT |
293 | return 0; |
294 | /* Corner case. Discard any symbols with the same value as | |
a3b81113 RG |
295 | * _etext _einittext; they can move between pass 1 and 2 when |
296 | * the kallsyms data are added. If these symbols move then | |
297 | * they may get dropped in pass 2, which breaks the kallsyms | |
298 | * rules. | |
1da177e4 | 299 | */ |
17b1f0de | 300 | if ((s->addr == text_range_text->end && |
29e55ad3 | 301 | strcmp(name, text_range_text->end_sym)) || |
17b1f0de | 302 | (s->addr == text_range_inittext->end && |
29e55ad3 | 303 | strcmp(name, text_range_inittext->end_sym))) |
1da177e4 LT |
304 | return 0; |
305 | } | |
306 | ||
1da177e4 LT |
307 | return 1; |
308 | } | |
309 | ||
5e5c4fa7 MY |
310 | /* remove all the invalid symbols from the table */ |
311 | static void shrink_table(void) | |
312 | { | |
313 | unsigned int i, pos; | |
314 | ||
315 | pos = 0; | |
316 | for (i = 0; i < table_cnt; i++) { | |
8d605269 | 317 | if (symbol_valid(table[i])) { |
5e5c4fa7 MY |
318 | if (pos != i) |
319 | table[pos] = table[i]; | |
320 | pos++; | |
321 | } else { | |
8d605269 | 322 | free(table[i]); |
5e5c4fa7 MY |
323 | } |
324 | } | |
325 | table_cnt = pos; | |
326 | ||
327 | /* When valid symbol is not registered, exit to error */ | |
328 | if (!table_cnt) { | |
329 | fprintf(stderr, "No valid symbol.\n"); | |
330 | exit(1); | |
331 | } | |
332 | } | |
333 | ||
aa221f2e | 334 | static void read_map(const char *in) |
1da177e4 | 335 | { |
aa221f2e | 336 | FILE *fp; |
8d605269 MY |
337 | struct sym_entry *sym; |
338 | ||
aa221f2e MY |
339 | fp = fopen(in, "r"); |
340 | if (!fp) { | |
341 | perror(in); | |
342 | exit(1); | |
343 | } | |
344 | ||
345 | while (!feof(fp)) { | |
346 | sym = read_symbol(fp); | |
8d605269 MY |
347 | if (!sym) |
348 | continue; | |
349 | ||
350 | sym->start_pos = table_cnt; | |
351 | ||
b3dbb4ec PM |
352 | if (table_cnt >= table_size) { |
353 | table_size += 10000; | |
354 | table = realloc(table, sizeof(*table) * table_size); | |
1da177e4 LT |
355 | if (!table) { |
356 | fprintf(stderr, "out of memory\n"); | |
aa221f2e | 357 | fclose(fp); |
1da177e4 LT |
358 | exit (1); |
359 | } | |
360 | } | |
8d605269 MY |
361 | |
362 | table[table_cnt++] = sym; | |
1da177e4 | 363 | } |
aa221f2e MY |
364 | |
365 | fclose(fp); | |
1da177e4 LT |
366 | } |
367 | ||
4bfe2b78 | 368 | static void output_label(const char *label) |
1da177e4 | 369 | { |
534c9f2e | 370 | printf(".globl %s\n", label); |
1da177e4 | 371 | printf("\tALGN\n"); |
534c9f2e | 372 | printf("%s:\n", label); |
1da177e4 LT |
373 | } |
374 | ||
fd2ab2f6 MY |
375 | /* Provide proper symbols relocatability by their '_text' relativeness. */ |
376 | static void output_address(unsigned long long addr) | |
377 | { | |
378 | if (_text <= addr) | |
379 | printf("\tPTR\t_text + %#llx\n", addr - _text); | |
380 | else | |
381 | printf("\tPTR\t_text - %#llx\n", _text - addr); | |
382 | } | |
383 | ||
1da177e4 LT |
384 | /* uncompress a compressed symbol. When this function is called, the best table |
385 | * might still be compressed itself, so the function needs to be recursive */ | |
4bfe2b78 | 386 | static int expand_symbol(const unsigned char *data, int len, char *result) |
1da177e4 LT |
387 | { |
388 | int c, rlen, total=0; | |
389 | ||
390 | while (len) { | |
391 | c = *data; | |
392 | /* if the table holds a single char that is the same as the one | |
393 | * we are looking for, then end the search */ | |
394 | if (best_table[c][0]==c && best_table_len[c]==1) { | |
395 | *result++ = c; | |
396 | total++; | |
397 | } else { | |
398 | /* if not, recurse and expand */ | |
399 | rlen = expand_symbol(best_table[c], best_table_len[c], result); | |
400 | total += rlen; | |
401 | result += rlen; | |
402 | } | |
403 | data++; | |
404 | len--; | |
405 | } | |
406 | *result=0; | |
407 | ||
408 | return total; | |
409 | } | |
410 | ||
4bfe2b78 | 411 | static int symbol_absolute(const struct sym_entry *s) |
78eb7159 | 412 | { |
8c996940 | 413 | return s->percpu_absolute; |
78eb7159 KC |
414 | } |
415 | ||
010a0aad ZL |
416 | static char * s_name(char *buf) |
417 | { | |
418 | /* Skip the symbol type */ | |
419 | return buf + 1; | |
420 | } | |
421 | ||
422 | static void cleanup_symbol_name(char *s) | |
423 | { | |
424 | char *p; | |
425 | ||
426 | if (!lto_clang) | |
427 | return; | |
428 | ||
429 | /* | |
430 | * ASCII[.] = 2e | |
431 | * ASCII[0-9] = 30,39 | |
432 | * ASCII[A-Z] = 41,5a | |
433 | * ASCII[_] = 5f | |
434 | * ASCII[a-z] = 61,7a | |
435 | * | |
436 | * As above, replacing '.' with '\0' does not affect the main sorting, | |
437 | * but it helps us with subsorting. | |
438 | */ | |
439 | p = strchr(s, '.'); | |
440 | if (p) | |
441 | *p = '\0'; | |
442 | } | |
443 | ||
60443c88 ZL |
444 | static int compare_names(const void *a, const void *b) |
445 | { | |
446 | int ret; | |
447 | char sa_namebuf[KSYM_NAME_LEN]; | |
448 | char sb_namebuf[KSYM_NAME_LEN]; | |
449 | const struct sym_entry *sa = *(const struct sym_entry **)a; | |
450 | const struct sym_entry *sb = *(const struct sym_entry **)b; | |
451 | ||
452 | expand_symbol(sa->sym, sa->len, sa_namebuf); | |
453 | expand_symbol(sb->sym, sb->len, sb_namebuf); | |
010a0aad ZL |
454 | cleanup_symbol_name(s_name(sa_namebuf)); |
455 | cleanup_symbol_name(s_name(sb_namebuf)); | |
456 | ret = strcmp(s_name(sa_namebuf), s_name(sb_namebuf)); | |
60443c88 ZL |
457 | if (!ret) { |
458 | if (sa->addr > sb->addr) | |
459 | return 1; | |
460 | else if (sa->addr < sb->addr) | |
461 | return -1; | |
462 | ||
463 | /* keep old order */ | |
464 | return (int)(sa->seq - sb->seq); | |
465 | } | |
466 | ||
467 | return ret; | |
468 | } | |
469 | ||
470 | static void sort_symbols_by_name(void) | |
471 | { | |
472 | qsort(table, table_cnt, sizeof(table[0]), compare_names); | |
473 | } | |
474 | ||
b3dbb4ec | 475 | static void write_src(void) |
1da177e4 | 476 | { |
b3dbb4ec | 477 | unsigned int i, k, off; |
1da177e4 LT |
478 | unsigned int best_idx[256]; |
479 | unsigned int *markers; | |
9281acea | 480 | char buf[KSYM_NAME_LEN]; |
1da177e4 | 481 | |
500193ec | 482 | printf("#include <asm/bitsperlong.h>\n"); |
1da177e4 LT |
483 | printf("#if BITS_PER_LONG == 64\n"); |
484 | printf("#define PTR .quad\n"); | |
72d3ebb9 | 485 | printf("#define ALGN .balign 8\n"); |
1da177e4 LT |
486 | printf("#else\n"); |
487 | printf("#define PTR .long\n"); | |
72d3ebb9 | 488 | printf("#define ALGN .balign 4\n"); |
1da177e4 LT |
489 | printf("#endif\n"); |
490 | ||
aad09470 | 491 | printf("\t.section .rodata, \"a\"\n"); |
1da177e4 | 492 | |
2213e9a6 AB |
493 | if (!base_relative) |
494 | output_label("kallsyms_addresses"); | |
495 | else | |
496 | output_label("kallsyms_offsets"); | |
497 | ||
b3dbb4ec | 498 | for (i = 0; i < table_cnt; i++) { |
2213e9a6 | 499 | if (base_relative) { |
fd2ab2f6 MY |
500 | /* |
501 | * Use the offset relative to the lowest value | |
502 | * encountered of all relative symbols, and emit | |
503 | * non-relocatable fixed offsets that will be fixed | |
504 | * up at runtime. | |
505 | */ | |
506 | ||
2213e9a6 AB |
507 | long long offset; |
508 | int overflow; | |
509 | ||
510 | if (!absolute_percpu) { | |
8d605269 | 511 | offset = table[i]->addr - relative_base; |
2213e9a6 | 512 | overflow = (offset < 0 || offset > UINT_MAX); |
8d605269 MY |
513 | } else if (symbol_absolute(table[i])) { |
514 | offset = table[i]->addr; | |
2213e9a6 AB |
515 | overflow = (offset < 0 || offset > INT_MAX); |
516 | } else { | |
8d605269 | 517 | offset = relative_base - table[i]->addr - 1; |
2213e9a6 AB |
518 | overflow = (offset < INT_MIN || offset >= 0); |
519 | } | |
520 | if (overflow) { | |
521 | fprintf(stderr, "kallsyms failure: " | |
522 | "%s symbol value %#llx out of range in relative mode\n", | |
8d605269 MY |
523 | symbol_absolute(table[i]) ? "absolute" : "relative", |
524 | table[i]->addr); | |
2213e9a6 AB |
525 | exit(EXIT_FAILURE); |
526 | } | |
527 | printf("\t.long\t%#x\n", (int)offset); | |
8d605269 MY |
528 | } else if (!symbol_absolute(table[i])) { |
529 | output_address(table[i]->addr); | |
fd593d12 | 530 | } else { |
8d605269 | 531 | printf("\tPTR\t%#llx\n", table[i]->addr); |
fd593d12 | 532 | } |
1da177e4 LT |
533 | } |
534 | printf("\n"); | |
535 | ||
2213e9a6 AB |
536 | if (base_relative) { |
537 | output_label("kallsyms_relative_base"); | |
fd2ab2f6 | 538 | output_address(relative_base); |
2213e9a6 AB |
539 | printf("\n"); |
540 | } | |
541 | ||
1da177e4 | 542 | output_label("kallsyms_num_syms"); |
80ffbaa5 | 543 | printf("\t.long\t%u\n", table_cnt); |
1da177e4 LT |
544 | printf("\n"); |
545 | ||
546 | /* table of offset markers, that give the offset in the compressed stream | |
547 | * every 256 symbols */ | |
f1a136e0 JJ |
548 | markers = malloc(sizeof(unsigned int) * ((table_cnt + 255) / 256)); |
549 | if (!markers) { | |
550 | fprintf(stderr, "kallsyms failure: " | |
551 | "unable to allocate required memory\n"); | |
552 | exit(EXIT_FAILURE); | |
553 | } | |
1da177e4 LT |
554 | |
555 | output_label("kallsyms_names"); | |
1da177e4 | 556 | off = 0; |
b3dbb4ec PM |
557 | for (i = 0; i < table_cnt; i++) { |
558 | if ((i & 0xFF) == 0) | |
559 | markers[i >> 8] = off; | |
60443c88 | 560 | table[i]->seq = i; |
1da177e4 | 561 | |
73bbb944 MO |
562 | /* There cannot be any symbol of length zero. */ |
563 | if (table[i]->len == 0) { | |
564 | fprintf(stderr, "kallsyms failure: " | |
565 | "unexpected zero symbol length\n"); | |
566 | exit(EXIT_FAILURE); | |
567 | } | |
568 | ||
569 | /* Only lengths that fit in up-to-two-byte ULEB128 are supported. */ | |
570 | if (table[i]->len > 0x3FFF) { | |
571 | fprintf(stderr, "kallsyms failure: " | |
572 | "unexpected huge symbol length\n"); | |
573 | exit(EXIT_FAILURE); | |
574 | } | |
575 | ||
576 | /* Encode length with ULEB128. */ | |
577 | if (table[i]->len <= 0x7F) { | |
578 | /* Most symbols use a single byte for the length. */ | |
579 | printf("\t.byte 0x%02x", table[i]->len); | |
580 | off += table[i]->len + 1; | |
581 | } else { | |
582 | /* "Big" symbols use two bytes. */ | |
583 | printf("\t.byte 0x%02x, 0x%02x", | |
584 | (table[i]->len & 0x7F) | 0x80, | |
585 | (table[i]->len >> 7) & 0x7F); | |
586 | off += table[i]->len + 2; | |
587 | } | |
8d605269 MY |
588 | for (k = 0; k < table[i]->len; k++) |
589 | printf(", 0x%02x", table[i]->sym[k]); | |
1da177e4 | 590 | printf("\n"); |
1da177e4 LT |
591 | } |
592 | printf("\n"); | |
593 | ||
594 | output_label("kallsyms_markers"); | |
b3dbb4ec | 595 | for (i = 0; i < ((table_cnt + 255) >> 8); i++) |
80ffbaa5 | 596 | printf("\t.long\t%u\n", markers[i]); |
1da177e4 LT |
597 | printf("\n"); |
598 | ||
599 | free(markers); | |
600 | ||
60443c88 ZL |
601 | sort_symbols_by_name(); |
602 | output_label("kallsyms_seqs_of_names"); | |
603 | for (i = 0; i < table_cnt; i++) | |
19bd8981 ZL |
604 | printf("\t.byte 0x%02x, 0x%02x, 0x%02x\n", |
605 | (unsigned char)(table[i]->seq >> 16), | |
606 | (unsigned char)(table[i]->seq >> 8), | |
607 | (unsigned char)(table[i]->seq >> 0)); | |
60443c88 ZL |
608 | printf("\n"); |
609 | ||
1da177e4 LT |
610 | output_label("kallsyms_token_table"); |
611 | off = 0; | |
612 | for (i = 0; i < 256; i++) { | |
613 | best_idx[i] = off; | |
b3dbb4ec | 614 | expand_symbol(best_table[i], best_table_len[i], buf); |
1da177e4 LT |
615 | printf("\t.asciz\t\"%s\"\n", buf); |
616 | off += strlen(buf) + 1; | |
617 | } | |
618 | printf("\n"); | |
619 | ||
620 | output_label("kallsyms_token_index"); | |
621 | for (i = 0; i < 256; i++) | |
622 | printf("\t.short\t%d\n", best_idx[i]); | |
623 | printf("\n"); | |
624 | } | |
625 | ||
626 | ||
627 | /* table lookup compression functions */ | |
628 | ||
1da177e4 | 629 | /* count all the possible tokens in a symbol */ |
4bfe2b78 | 630 | static void learn_symbol(const unsigned char *symbol, int len) |
1da177e4 LT |
631 | { |
632 | int i; | |
633 | ||
634 | for (i = 0; i < len - 1; i++) | |
b3dbb4ec | 635 | token_profit[ symbol[i] + (symbol[i + 1] << 8) ]++; |
1da177e4 LT |
636 | } |
637 | ||
638 | /* decrease the count for all the possible tokens in a symbol */ | |
4bfe2b78 | 639 | static void forget_symbol(const unsigned char *symbol, int len) |
1da177e4 LT |
640 | { |
641 | int i; | |
642 | ||
643 | for (i = 0; i < len - 1; i++) | |
b3dbb4ec | 644 | token_profit[ symbol[i] + (symbol[i + 1] << 8) ]--; |
1da177e4 LT |
645 | } |
646 | ||
5e5c4fa7 | 647 | /* do the initial token count */ |
fcdf7197 | 648 | static void build_initial_token_table(void) |
1da177e4 | 649 | { |
5e5c4fa7 | 650 | unsigned int i; |
1da177e4 | 651 | |
5e5c4fa7 | 652 | for (i = 0; i < table_cnt; i++) |
8d605269 | 653 | learn_symbol(table[i]->sym, table[i]->len); |
1da177e4 LT |
654 | } |
655 | ||
2558c138 | 656 | static unsigned char *find_token(unsigned char *str, int len, |
4bfe2b78 | 657 | const unsigned char *token) |
7c5d249a PM |
658 | { |
659 | int i; | |
660 | ||
661 | for (i = 0; i < len - 1; i++) { | |
662 | if (str[i] == token[0] && str[i+1] == token[1]) | |
663 | return &str[i]; | |
664 | } | |
665 | return NULL; | |
666 | } | |
667 | ||
1da177e4 LT |
668 | /* replace a given token in all the valid symbols. Use the sampled symbols |
669 | * to update the counts */ | |
4bfe2b78 | 670 | static void compress_symbols(const unsigned char *str, int idx) |
1da177e4 | 671 | { |
b3dbb4ec PM |
672 | unsigned int i, len, size; |
673 | unsigned char *p1, *p2; | |
1da177e4 | 674 | |
b3dbb4ec | 675 | for (i = 0; i < table_cnt; i++) { |
1da177e4 | 676 | |
8d605269 MY |
677 | len = table[i]->len; |
678 | p1 = table[i]->sym; | |
b3dbb4ec PM |
679 | |
680 | /* find the token on the symbol */ | |
7c5d249a | 681 | p2 = find_token(p1, len, str); |
b3dbb4ec PM |
682 | if (!p2) continue; |
683 | ||
684 | /* decrease the counts for this symbol's tokens */ | |
8d605269 | 685 | forget_symbol(table[i]->sym, len); |
b3dbb4ec PM |
686 | |
687 | size = len; | |
1da177e4 LT |
688 | |
689 | do { | |
b3dbb4ec PM |
690 | *p2 = idx; |
691 | p2++; | |
692 | size -= (p2 - p1); | |
693 | memmove(p2, p2 + 1, size); | |
694 | p1 = p2; | |
695 | len--; | |
696 | ||
697 | if (size < 2) break; | |
698 | ||
1da177e4 | 699 | /* find the token on the symbol */ |
7c5d249a | 700 | p2 = find_token(p1, size, str); |
1da177e4 | 701 | |
b3dbb4ec | 702 | } while (p2); |
1da177e4 | 703 | |
8d605269 | 704 | table[i]->len = len; |
1da177e4 | 705 | |
b3dbb4ec | 706 | /* increase the counts for this symbol's new tokens */ |
8d605269 | 707 | learn_symbol(table[i]->sym, len); |
1da177e4 LT |
708 | } |
709 | } | |
710 | ||
711 | /* search the token with the maximum profit */ | |
b3dbb4ec | 712 | static int find_best_token(void) |
1da177e4 | 713 | { |
b3dbb4ec | 714 | int i, best, bestprofit; |
1da177e4 LT |
715 | |
716 | bestprofit=-10000; | |
b3dbb4ec | 717 | best = 0; |
1da177e4 | 718 | |
b3dbb4ec PM |
719 | for (i = 0; i < 0x10000; i++) { |
720 | if (token_profit[i] > bestprofit) { | |
721 | best = i; | |
722 | bestprofit = token_profit[i]; | |
1da177e4 | 723 | } |
1da177e4 | 724 | } |
1da177e4 LT |
725 | return best; |
726 | } | |
727 | ||
728 | /* this is the core of the algorithm: calculate the "best" table */ | |
729 | static void optimize_result(void) | |
730 | { | |
b3dbb4ec | 731 | int i, best; |
1da177e4 LT |
732 | |
733 | /* using the '\0' symbol last allows compress_symbols to use standard | |
734 | * fast string functions */ | |
735 | for (i = 255; i >= 0; i--) { | |
736 | ||
737 | /* if this table slot is empty (it is not used by an actual | |
738 | * original char code */ | |
739 | if (!best_table_len[i]) { | |
740 | ||
cbf7a90e | 741 | /* find the token with the best profit value */ |
1da177e4 | 742 | best = find_best_token(); |
e0a04b11 XW |
743 | if (token_profit[best] == 0) |
744 | break; | |
1da177e4 LT |
745 | |
746 | /* place it in the "best" table */ | |
b3dbb4ec PM |
747 | best_table_len[i] = 2; |
748 | best_table[i][0] = best & 0xFF; | |
749 | best_table[i][1] = (best >> 8) & 0xFF; | |
1da177e4 LT |
750 | |
751 | /* replace this token in all the valid symbols */ | |
b3dbb4ec | 752 | compress_symbols(best_table[i], i); |
1da177e4 LT |
753 | } |
754 | } | |
755 | } | |
756 | ||
757 | /* start by placing the symbols that are actually used on the table */ | |
758 | static void insert_real_symbols_in_table(void) | |
759 | { | |
b3dbb4ec | 760 | unsigned int i, j, c; |
1da177e4 | 761 | |
b3dbb4ec | 762 | for (i = 0; i < table_cnt; i++) { |
8d605269 MY |
763 | for (j = 0; j < table[i]->len; j++) { |
764 | c = table[i]->sym[j]; | |
b3dbb4ec PM |
765 | best_table[c][0]=c; |
766 | best_table_len[c]=1; | |
1da177e4 LT |
767 | } |
768 | } | |
769 | } | |
770 | ||
771 | static void optimize_token_table(void) | |
772 | { | |
fcdf7197 | 773 | build_initial_token_table(); |
1da177e4 LT |
774 | |
775 | insert_real_symbols_in_table(); | |
776 | ||
777 | optimize_result(); | |
778 | } | |
779 | ||
b478b782 LJ |
780 | /* guess for "linker script provide" symbol */ |
781 | static int may_be_linker_script_provide_symbol(const struct sym_entry *se) | |
782 | { | |
29e55ad3 | 783 | const char *symbol = sym_name(se); |
b478b782 LJ |
784 | int len = se->len - 1; |
785 | ||
786 | if (len < 8) | |
787 | return 0; | |
788 | ||
789 | if (symbol[0] != '_' || symbol[1] != '_') | |
790 | return 0; | |
791 | ||
792 | /* __start_XXXXX */ | |
793 | if (!memcmp(symbol + 2, "start_", 6)) | |
794 | return 1; | |
795 | ||
796 | /* __stop_XXXXX */ | |
797 | if (!memcmp(symbol + 2, "stop_", 5)) | |
798 | return 1; | |
799 | ||
800 | /* __end_XXXXX */ | |
801 | if (!memcmp(symbol + 2, "end_", 4)) | |
802 | return 1; | |
803 | ||
804 | /* __XXXXX_start */ | |
805 | if (!memcmp(symbol + len - 6, "_start", 6)) | |
806 | return 1; | |
807 | ||
808 | /* __XXXXX_end */ | |
809 | if (!memcmp(symbol + len - 4, "_end", 4)) | |
810 | return 1; | |
811 | ||
812 | return 0; | |
813 | } | |
814 | ||
f2df3f65 PM |
815 | static int compare_symbols(const void *a, const void *b) |
816 | { | |
8d605269 MY |
817 | const struct sym_entry *sa = *(const struct sym_entry **)a; |
818 | const struct sym_entry *sb = *(const struct sym_entry **)b; | |
f2df3f65 PM |
819 | int wa, wb; |
820 | ||
f2df3f65 PM |
821 | /* sort by address first */ |
822 | if (sa->addr > sb->addr) | |
823 | return 1; | |
824 | if (sa->addr < sb->addr) | |
825 | return -1; | |
826 | ||
827 | /* sort by "weakness" type */ | |
828 | wa = (sa->sym[0] == 'w') || (sa->sym[0] == 'W'); | |
829 | wb = (sb->sym[0] == 'w') || (sb->sym[0] == 'W'); | |
830 | if (wa != wb) | |
831 | return wa - wb; | |
832 | ||
b478b782 LJ |
833 | /* sort by "linker script provide" type */ |
834 | wa = may_be_linker_script_provide_symbol(sa); | |
835 | wb = may_be_linker_script_provide_symbol(sb); | |
836 | if (wa != wb) | |
837 | return wa - wb; | |
838 | ||
839 | /* sort by the number of prefix underscores */ | |
aa915245 MY |
840 | wa = strspn(sym_name(sa), "_"); |
841 | wb = strspn(sym_name(sb), "_"); | |
b478b782 LJ |
842 | if (wa != wb) |
843 | return wa - wb; | |
844 | ||
f2df3f65 PM |
845 | /* sort by initial order, so that other symbols are left undisturbed */ |
846 | return sa->start_pos - sb->start_pos; | |
847 | } | |
848 | ||
849 | static void sort_symbols(void) | |
850 | { | |
8d605269 | 851 | qsort(table, table_cnt, sizeof(table[0]), compare_symbols); |
f2df3f65 | 852 | } |
1da177e4 | 853 | |
c6bda7c9 RR |
854 | static void make_percpus_absolute(void) |
855 | { | |
856 | unsigned int i; | |
857 | ||
858 | for (i = 0; i < table_cnt; i++) | |
8d605269 | 859 | if (symbol_in_range(table[i], &percpu_range, 1)) { |
8c996940 AB |
860 | /* |
861 | * Keep the 'A' override for percpu symbols to | |
862 | * ensure consistent behavior compared to older | |
863 | * versions of this tool. | |
864 | */ | |
8d605269 MY |
865 | table[i]->sym[0] = 'A'; |
866 | table[i]->percpu_absolute = 1; | |
8c996940 | 867 | } |
c6bda7c9 RR |
868 | } |
869 | ||
2213e9a6 AB |
870 | /* find the minimum non-absolute symbol address */ |
871 | static void record_relative_base(void) | |
872 | { | |
873 | unsigned int i; | |
874 | ||
2213e9a6 | 875 | for (i = 0; i < table_cnt; i++) |
8d605269 | 876 | if (!symbol_absolute(table[i])) { |
f34ea029 MY |
877 | /* |
878 | * The table is sorted by address. | |
879 | * Take the first non-absolute symbol value. | |
880 | */ | |
8d605269 | 881 | relative_base = table[i]->addr; |
f34ea029 MY |
882 | return; |
883 | } | |
2213e9a6 AB |
884 | } |
885 | ||
b3dbb4ec | 886 | int main(int argc, char **argv) |
1da177e4 | 887 | { |
aa221f2e MY |
888 | while (1) { |
889 | static struct option long_options[] = { | |
890 | {"all-symbols", no_argument, &all_symbols, 1}, | |
891 | {"absolute-percpu", no_argument, &absolute_percpu, 1}, | |
892 | {"base-relative", no_argument, &base_relative, 1}, | |
010a0aad | 893 | {"lto-clang", no_argument, <o_clang, 1}, |
aa221f2e MY |
894 | {}, |
895 | }; | |
896 | ||
897 | int c = getopt_long(argc, argv, "", long_options, NULL); | |
898 | ||
899 | if (c == -1) | |
900 | break; | |
901 | if (c != 0) | |
902 | usage(); | |
903 | } | |
904 | ||
905 | if (optind >= argc) | |
1da177e4 LT |
906 | usage(); |
907 | ||
aa221f2e | 908 | read_map(argv[optind]); |
5e5c4fa7 | 909 | shrink_table(); |
c6bda7c9 RR |
910 | if (absolute_percpu) |
911 | make_percpus_absolute(); | |
f34ea029 | 912 | sort_symbols(); |
2213e9a6 AB |
913 | if (base_relative) |
914 | record_relative_base(); | |
2ea03891 | 915 | optimize_token_table(); |
1da177e4 LT |
916 | write_src(); |
917 | ||
918 | return 0; | |
919 | } |