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