blob: 1f22a186c18cb56a2c19a4b38bf90f41f1b171d8
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 | * |
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 | |
21 | #include <stdio.h> |
22 | #include <stdlib.h> |
23 | #include <string.h> |
24 | #include <ctype.h> |
25 | #include <limits.h> |
26 | |
27 | #ifndef ARRAY_SIZE |
28 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0])) |
29 | #endif |
30 | |
31 | #define KSYM_NAME_LEN 128 |
32 | |
33 | struct sym_entry { |
34 | unsigned long long addr; |
35 | unsigned int len; |
36 | unsigned int start_pos; |
37 | unsigned char *sym; |
38 | unsigned int percpu_absolute; |
39 | }; |
40 | |
41 | struct addr_range { |
42 | const char *start_sym, *end_sym; |
43 | unsigned long long start, end; |
44 | }; |
45 | |
46 | static unsigned long long _text; |
47 | static unsigned long long relative_base; |
48 | static struct addr_range text_ranges[] = { |
49 | { "_stext", "_etext" }, |
50 | { "_sinittext", "_einittext" }, |
51 | { "_stext_l1", "_etext_l1" }, /* Blackfin on-chip L1 inst SRAM */ |
52 | { "_stext_l2", "_etext_l2" }, /* Blackfin on-chip L2 SRAM */ |
53 | }; |
54 | #define text_range_text (&text_ranges[0]) |
55 | #define text_range_inittext (&text_ranges[1]) |
56 | |
57 | static struct addr_range percpu_range = { |
58 | "__per_cpu_start", "__per_cpu_end", -1ULL, 0 |
59 | }; |
60 | |
61 | static struct sym_entry *table; |
62 | static unsigned int table_size, table_cnt; |
63 | static int all_symbols = 0; |
64 | static int absolute_percpu = 0; |
65 | static char symbol_prefix_char = '\0'; |
66 | static int base_relative = 0; |
67 | |
68 | int token_profit[0x10000]; |
69 | |
70 | /* the table that holds the result of the compression */ |
71 | unsigned char best_table[256][2]; |
72 | unsigned char best_table_len[256]; |
73 | |
74 | |
75 | static void usage(void) |
76 | { |
77 | fprintf(stderr, "Usage: kallsyms [--all-symbols] " |
78 | "[--symbol-prefix=<prefix char>] " |
79 | "[--page-offset=<CONFIG_PAGE_OFFSET>] " |
80 | "[--base-relative] < in.map > out.S\n"); |
81 | exit(1); |
82 | } |
83 | |
84 | /* |
85 | * This ignores the intensely annoying "mapping symbols" found |
86 | * in ARM ELF files: $a, $t and $d. |
87 | */ |
88 | static inline int is_arm_mapping_symbol(const char *str) |
89 | { |
90 | return str[0] == '$' && strchr("axtd", str[1]) |
91 | && (str[2] == '\0' || str[2] == '.'); |
92 | } |
93 | |
94 | static int check_symbol_range(const char *sym, unsigned long long addr, |
95 | struct addr_range *ranges, int entries) |
96 | { |
97 | size_t i; |
98 | struct addr_range *ar; |
99 | |
100 | for (i = 0; i < entries; ++i) { |
101 | ar = &ranges[i]; |
102 | |
103 | if (strcmp(sym, ar->start_sym) == 0) { |
104 | ar->start = addr; |
105 | return 0; |
106 | } else if (strcmp(sym, ar->end_sym) == 0) { |
107 | ar->end = addr; |
108 | return 0; |
109 | } |
110 | } |
111 | |
112 | return 1; |
113 | } |
114 | |
115 | static int read_symbol(FILE *in, struct sym_entry *s) |
116 | { |
117 | char str[500]; |
118 | char *sym, stype; |
119 | int rc; |
120 | |
121 | rc = fscanf(in, "%llx %c %499s\n", &s->addr, &stype, str); |
122 | if (rc != 3) { |
123 | if (rc != EOF && fgets(str, 500, in) == NULL) |
124 | fprintf(stderr, "Read error or end of file.\n"); |
125 | return -1; |
126 | } |
127 | if (strlen(str) > KSYM_NAME_LEN) { |
128 | fprintf(stderr, "Symbol %s too long for kallsyms (%zu vs %d).\n" |
129 | "Please increase KSYM_NAME_LEN both in kernel and kallsyms.c\n", |
130 | str, strlen(str), KSYM_NAME_LEN); |
131 | return -1; |
132 | } |
133 | |
134 | sym = str; |
135 | /* skip prefix char */ |
136 | if (symbol_prefix_char && str[0] == symbol_prefix_char) |
137 | sym++; |
138 | |
139 | /* Ignore most absolute/undefined (?) symbols. */ |
140 | if (strcmp(sym, "_text") == 0) |
141 | _text = s->addr; |
142 | else if (check_symbol_range(sym, s->addr, text_ranges, |
143 | ARRAY_SIZE(text_ranges)) == 0) |
144 | /* nothing to do */; |
145 | else if (toupper(stype) == 'A') |
146 | { |
147 | /* Keep these useful absolute symbols */ |
148 | if (strcmp(sym, "__kernel_syscall_via_break") && |
149 | strcmp(sym, "__kernel_syscall_via_epc") && |
150 | strcmp(sym, "__kernel_sigtramp") && |
151 | strcmp(sym, "__gp")) |
152 | return -1; |
153 | |
154 | } |
155 | else if (toupper(stype) == 'U' || |
156 | is_arm_mapping_symbol(sym)) |
157 | return -1; |
158 | /* exclude also MIPS ELF local symbols ($L123 instead of .L123) */ |
159 | else if (str[0] == '$') |
160 | return -1; |
161 | /* exclude debugging symbols */ |
162 | else if (stype == 'N') |
163 | return -1; |
164 | |
165 | /* include the type field in the symbol name, so that it gets |
166 | * compressed together */ |
167 | s->len = strlen(str) + 1; |
168 | s->sym = malloc(s->len + 1); |
169 | if (!s->sym) { |
170 | fprintf(stderr, "kallsyms failure: " |
171 | "unable to allocate required amount of memory\n"); |
172 | exit(EXIT_FAILURE); |
173 | } |
174 | strcpy((char *)s->sym + 1, str); |
175 | s->sym[0] = stype; |
176 | |
177 | s->percpu_absolute = 0; |
178 | |
179 | /* Record if we've found __per_cpu_start/end. */ |
180 | check_symbol_range(sym, s->addr, &percpu_range, 1); |
181 | |
182 | return 0; |
183 | } |
184 | |
185 | static int symbol_in_range(struct sym_entry *s, struct addr_range *ranges, |
186 | int entries) |
187 | { |
188 | size_t i; |
189 | struct addr_range *ar; |
190 | |
191 | for (i = 0; i < entries; ++i) { |
192 | ar = &ranges[i]; |
193 | |
194 | if (s->addr >= ar->start && s->addr <= ar->end) |
195 | return 1; |
196 | } |
197 | |
198 | return 0; |
199 | } |
200 | |
201 | static int symbol_valid(struct sym_entry *s) |
202 | { |
203 | /* Symbols which vary between passes. Passes 1 and 2 must have |
204 | * identical symbol lists. The kallsyms_* symbols below are only added |
205 | * after pass 1, they would be included in pass 2 when --all-symbols is |
206 | * specified so exclude them to get a stable symbol list. |
207 | */ |
208 | static char *special_symbols[] = { |
209 | "kallsyms_addresses", |
210 | "kallsyms_offsets", |
211 | "kallsyms_relative_base", |
212 | "kallsyms_num_syms", |
213 | "kallsyms_names", |
214 | "kallsyms_markers", |
215 | "kallsyms_token_table", |
216 | "kallsyms_token_index", |
217 | |
218 | /* Exclude linker generated symbols which vary between passes */ |
219 | "_SDA_BASE_", /* ppc */ |
220 | "_SDA2_BASE_", /* ppc */ |
221 | NULL }; |
222 | |
223 | static char *special_suffixes[] = { |
224 | "_veneer", /* arm */ |
225 | "_from_arm", /* arm */ |
226 | "_from_thumb", /* arm */ |
227 | NULL }; |
228 | |
229 | int i; |
230 | char *sym_name = (char *)s->sym + 1; |
231 | |
232 | /* skip prefix char */ |
233 | if (symbol_prefix_char && *sym_name == symbol_prefix_char) |
234 | sym_name++; |
235 | |
236 | |
237 | /* if --all-symbols is not specified, then symbols outside the text |
238 | * and inittext sections are discarded */ |
239 | if (!all_symbols) { |
240 | if (symbol_in_range(s, text_ranges, |
241 | ARRAY_SIZE(text_ranges)) == 0) |
242 | return 0; |
243 | /* Corner case. Discard any symbols with the same value as |
244 | * _etext _einittext; they can move between pass 1 and 2 when |
245 | * the kallsyms data are added. If these symbols move then |
246 | * they may get dropped in pass 2, which breaks the kallsyms |
247 | * rules. |
248 | */ |
249 | if ((s->addr == text_range_text->end && |
250 | strcmp(sym_name, |
251 | text_range_text->end_sym)) || |
252 | (s->addr == text_range_inittext->end && |
253 | strcmp(sym_name, |
254 | text_range_inittext->end_sym))) |
255 | return 0; |
256 | } |
257 | |
258 | /* Exclude symbols which vary between passes. */ |
259 | for (i = 0; special_symbols[i]; i++) |
260 | if (strcmp(sym_name, special_symbols[i]) == 0) |
261 | return 0; |
262 | |
263 | for (i = 0; special_suffixes[i]; i++) { |
264 | int l = strlen(sym_name) - strlen(special_suffixes[i]); |
265 | |
266 | if (l >= 0 && strcmp(sym_name + l, special_suffixes[i]) == 0) |
267 | return 0; |
268 | } |
269 | |
270 | return 1; |
271 | } |
272 | |
273 | static void read_map(FILE *in) |
274 | { |
275 | while (!feof(in)) { |
276 | if (table_cnt >= table_size) { |
277 | table_size += 10000; |
278 | table = realloc(table, sizeof(*table) * table_size); |
279 | if (!table) { |
280 | fprintf(stderr, "out of memory\n"); |
281 | exit (1); |
282 | } |
283 | } |
284 | if (read_symbol(in, &table[table_cnt]) == 0) { |
285 | table[table_cnt].start_pos = table_cnt; |
286 | table_cnt++; |
287 | } |
288 | } |
289 | } |
290 | |
291 | static void output_label(char *label) |
292 | { |
293 | if (symbol_prefix_char) |
294 | printf(".globl %c%s\n", symbol_prefix_char, label); |
295 | else |
296 | printf(".globl %s\n", label); |
297 | printf("\tALGN\n"); |
298 | if (symbol_prefix_char) |
299 | printf("%c%s:\n", symbol_prefix_char, label); |
300 | else |
301 | printf("%s:\n", label); |
302 | } |
303 | |
304 | /* uncompress a compressed symbol. When this function is called, the best table |
305 | * might still be compressed itself, so the function needs to be recursive */ |
306 | static int expand_symbol(unsigned char *data, int len, char *result) |
307 | { |
308 | int c, rlen, total=0; |
309 | |
310 | while (len) { |
311 | c = *data; |
312 | /* if the table holds a single char that is the same as the one |
313 | * we are looking for, then end the search */ |
314 | if (best_table[c][0]==c && best_table_len[c]==1) { |
315 | *result++ = c; |
316 | total++; |
317 | } else { |
318 | /* if not, recurse and expand */ |
319 | rlen = expand_symbol(best_table[c], best_table_len[c], result); |
320 | total += rlen; |
321 | result += rlen; |
322 | } |
323 | data++; |
324 | len--; |
325 | } |
326 | *result=0; |
327 | |
328 | return total; |
329 | } |
330 | |
331 | static int symbol_absolute(struct sym_entry *s) |
332 | { |
333 | return s->percpu_absolute; |
334 | } |
335 | |
336 | static void write_src(void) |
337 | { |
338 | unsigned int i, k, off; |
339 | unsigned int best_idx[256]; |
340 | unsigned int *markers; |
341 | char buf[KSYM_NAME_LEN]; |
342 | |
343 | printf("#include <asm/types.h>\n"); |
344 | printf("#if BITS_PER_LONG == 64\n"); |
345 | printf("#define PTR .quad\n"); |
346 | printf("#define ALGN .align 8\n"); |
347 | printf("#else\n"); |
348 | printf("#define PTR .long\n"); |
349 | printf("#define ALGN .align 4\n"); |
350 | printf("#endif\n"); |
351 | |
352 | printf("\t.section .rodata, \"a\"\n"); |
353 | |
354 | /* Provide proper symbols relocatability by their relativeness |
355 | * to a fixed anchor point in the runtime image, either '_text' |
356 | * for absolute address tables, in which case the linker will |
357 | * emit the final addresses at build time. Otherwise, use the |
358 | * offset relative to the lowest value encountered of all relative |
359 | * symbols, and emit non-relocatable fixed offsets that will be fixed |
360 | * up at runtime. |
361 | * |
362 | * The symbol names cannot be used to construct normal symbol |
363 | * references as the list of symbols contains symbols that are |
364 | * declared static and are private to their .o files. This prevents |
365 | * .tmp_kallsyms.o or any other object from referencing them. |
366 | */ |
367 | if (!base_relative) |
368 | output_label("kallsyms_addresses"); |
369 | else |
370 | output_label("kallsyms_offsets"); |
371 | |
372 | for (i = 0; i < table_cnt; i++) { |
373 | if (base_relative) { |
374 | long long offset; |
375 | int overflow; |
376 | |
377 | if (!absolute_percpu) { |
378 | offset = table[i].addr - relative_base; |
379 | overflow = (offset < 0 || offset > UINT_MAX); |
380 | } else if (symbol_absolute(&table[i])) { |
381 | offset = table[i].addr; |
382 | overflow = (offset < 0 || offset > INT_MAX); |
383 | } else { |
384 | offset = relative_base - table[i].addr - 1; |
385 | overflow = (offset < INT_MIN || offset >= 0); |
386 | } |
387 | if (overflow) { |
388 | fprintf(stderr, "kallsyms failure: " |
389 | "%s symbol value %#llx out of range in relative mode\n", |
390 | symbol_absolute(&table[i]) ? "absolute" : "relative", |
391 | table[i].addr); |
392 | exit(EXIT_FAILURE); |
393 | } |
394 | printf("\t.long\t%#x\n", (int)offset); |
395 | } else if (!symbol_absolute(&table[i])) { |
396 | if (_text <= table[i].addr) |
397 | printf("\tPTR\t_text + %#llx\n", |
398 | table[i].addr - _text); |
399 | else |
400 | printf("\tPTR\t_text - %#llx\n", |
401 | _text - table[i].addr); |
402 | } else { |
403 | printf("\tPTR\t%#llx\n", table[i].addr); |
404 | } |
405 | } |
406 | printf("\n"); |
407 | |
408 | if (base_relative) { |
409 | output_label("kallsyms_relative_base"); |
410 | printf("\tPTR\t_text - %#llx\n", _text - relative_base); |
411 | printf("\n"); |
412 | } |
413 | |
414 | output_label("kallsyms_num_syms"); |
415 | printf("\tPTR\t%d\n", table_cnt); |
416 | printf("\n"); |
417 | |
418 | /* table of offset markers, that give the offset in the compressed stream |
419 | * every 256 symbols */ |
420 | markers = malloc(sizeof(unsigned int) * ((table_cnt + 255) / 256)); |
421 | if (!markers) { |
422 | fprintf(stderr, "kallsyms failure: " |
423 | "unable to allocate required memory\n"); |
424 | exit(EXIT_FAILURE); |
425 | } |
426 | |
427 | output_label("kallsyms_names"); |
428 | off = 0; |
429 | for (i = 0; i < table_cnt; i++) { |
430 | if ((i & 0xFF) == 0) |
431 | markers[i >> 8] = off; |
432 | |
433 | printf("\t.byte 0x%02x", table[i].len); |
434 | for (k = 0; k < table[i].len; k++) |
435 | printf(", 0x%02x", table[i].sym[k]); |
436 | printf("\n"); |
437 | |
438 | off += table[i].len + 1; |
439 | } |
440 | printf("\n"); |
441 | |
442 | output_label("kallsyms_markers"); |
443 | for (i = 0; i < ((table_cnt + 255) >> 8); i++) |
444 | printf("\tPTR\t%d\n", markers[i]); |
445 | printf("\n"); |
446 | |
447 | free(markers); |
448 | |
449 | output_label("kallsyms_token_table"); |
450 | off = 0; |
451 | for (i = 0; i < 256; i++) { |
452 | best_idx[i] = off; |
453 | expand_symbol(best_table[i], best_table_len[i], buf); |
454 | printf("\t.asciz\t\"%s\"\n", buf); |
455 | off += strlen(buf) + 1; |
456 | } |
457 | printf("\n"); |
458 | |
459 | output_label("kallsyms_token_index"); |
460 | for (i = 0; i < 256; i++) |
461 | printf("\t.short\t%d\n", best_idx[i]); |
462 | printf("\n"); |
463 | } |
464 | |
465 | |
466 | /* table lookup compression functions */ |
467 | |
468 | /* count all the possible tokens in a symbol */ |
469 | static void learn_symbol(unsigned char *symbol, int len) |
470 | { |
471 | int i; |
472 | |
473 | for (i = 0; i < len - 1; i++) |
474 | token_profit[ symbol[i] + (symbol[i + 1] << 8) ]++; |
475 | } |
476 | |
477 | /* decrease the count for all the possible tokens in a symbol */ |
478 | static void forget_symbol(unsigned char *symbol, int len) |
479 | { |
480 | int i; |
481 | |
482 | for (i = 0; i < len - 1; i++) |
483 | token_profit[ symbol[i] + (symbol[i + 1] << 8) ]--; |
484 | } |
485 | |
486 | /* remove all the invalid symbols from the table and do the initial token count */ |
487 | static void build_initial_tok_table(void) |
488 | { |
489 | unsigned int i, pos; |
490 | |
491 | pos = 0; |
492 | for (i = 0; i < table_cnt; i++) { |
493 | if ( symbol_valid(&table[i]) ) { |
494 | if (pos != i) |
495 | table[pos] = table[i]; |
496 | learn_symbol(table[pos].sym, table[pos].len); |
497 | pos++; |
498 | } |
499 | } |
500 | table_cnt = pos; |
501 | } |
502 | |
503 | static void *find_token(unsigned char *str, int len, unsigned char *token) |
504 | { |
505 | int i; |
506 | |
507 | for (i = 0; i < len - 1; i++) { |
508 | if (str[i] == token[0] && str[i+1] == token[1]) |
509 | return &str[i]; |
510 | } |
511 | return NULL; |
512 | } |
513 | |
514 | /* replace a given token in all the valid symbols. Use the sampled symbols |
515 | * to update the counts */ |
516 | static void compress_symbols(unsigned char *str, int idx) |
517 | { |
518 | unsigned int i, len, size; |
519 | unsigned char *p1, *p2; |
520 | |
521 | for (i = 0; i < table_cnt; i++) { |
522 | |
523 | len = table[i].len; |
524 | p1 = table[i].sym; |
525 | |
526 | /* find the token on the symbol */ |
527 | p2 = find_token(p1, len, str); |
528 | if (!p2) continue; |
529 | |
530 | /* decrease the counts for this symbol's tokens */ |
531 | forget_symbol(table[i].sym, len); |
532 | |
533 | size = len; |
534 | |
535 | do { |
536 | *p2 = idx; |
537 | p2++; |
538 | size -= (p2 - p1); |
539 | memmove(p2, p2 + 1, size); |
540 | p1 = p2; |
541 | len--; |
542 | |
543 | if (size < 2) break; |
544 | |
545 | /* find the token on the symbol */ |
546 | p2 = find_token(p1, size, str); |
547 | |
548 | } while (p2); |
549 | |
550 | table[i].len = len; |
551 | |
552 | /* increase the counts for this symbol's new tokens */ |
553 | learn_symbol(table[i].sym, len); |
554 | } |
555 | } |
556 | |
557 | /* search the token with the maximum profit */ |
558 | static int find_best_token(void) |
559 | { |
560 | int i, best, bestprofit; |
561 | |
562 | bestprofit=-10000; |
563 | best = 0; |
564 | |
565 | for (i = 0; i < 0x10000; i++) { |
566 | if (token_profit[i] > bestprofit) { |
567 | best = i; |
568 | bestprofit = token_profit[i]; |
569 | } |
570 | } |
571 | return best; |
572 | } |
573 | |
574 | /* this is the core of the algorithm: calculate the "best" table */ |
575 | static void optimize_result(void) |
576 | { |
577 | int i, best; |
578 | |
579 | /* using the '\0' symbol last allows compress_symbols to use standard |
580 | * fast string functions */ |
581 | for (i = 255; i >= 0; i--) { |
582 | |
583 | /* if this table slot is empty (it is not used by an actual |
584 | * original char code */ |
585 | if (!best_table_len[i]) { |
586 | |
587 | /* find the token with the breates profit value */ |
588 | best = find_best_token(); |
589 | if (token_profit[best] == 0) |
590 | break; |
591 | |
592 | /* place it in the "best" table */ |
593 | best_table_len[i] = 2; |
594 | best_table[i][0] = best & 0xFF; |
595 | best_table[i][1] = (best >> 8) & 0xFF; |
596 | |
597 | /* replace this token in all the valid symbols */ |
598 | compress_symbols(best_table[i], i); |
599 | } |
600 | } |
601 | } |
602 | |
603 | /* start by placing the symbols that are actually used on the table */ |
604 | static void insert_real_symbols_in_table(void) |
605 | { |
606 | unsigned int i, j, c; |
607 | |
608 | memset(best_table, 0, sizeof(best_table)); |
609 | memset(best_table_len, 0, sizeof(best_table_len)); |
610 | |
611 | for (i = 0; i < table_cnt; i++) { |
612 | for (j = 0; j < table[i].len; j++) { |
613 | c = table[i].sym[j]; |
614 | best_table[c][0]=c; |
615 | best_table_len[c]=1; |
616 | } |
617 | } |
618 | } |
619 | |
620 | static void optimize_token_table(void) |
621 | { |
622 | build_initial_tok_table(); |
623 | |
624 | insert_real_symbols_in_table(); |
625 | |
626 | /* When valid symbol is not registered, exit to error */ |
627 | if (!table_cnt) { |
628 | fprintf(stderr, "No valid symbol.\n"); |
629 | exit(1); |
630 | } |
631 | |
632 | optimize_result(); |
633 | } |
634 | |
635 | /* guess for "linker script provide" symbol */ |
636 | static int may_be_linker_script_provide_symbol(const struct sym_entry *se) |
637 | { |
638 | const char *symbol = (char *)se->sym + 1; |
639 | int len = se->len - 1; |
640 | |
641 | if (len < 8) |
642 | return 0; |
643 | |
644 | if (symbol[0] != '_' || symbol[1] != '_') |
645 | return 0; |
646 | |
647 | /* __start_XXXXX */ |
648 | if (!memcmp(symbol + 2, "start_", 6)) |
649 | return 1; |
650 | |
651 | /* __stop_XXXXX */ |
652 | if (!memcmp(symbol + 2, "stop_", 5)) |
653 | return 1; |
654 | |
655 | /* __end_XXXXX */ |
656 | if (!memcmp(symbol + 2, "end_", 4)) |
657 | return 1; |
658 | |
659 | /* __XXXXX_start */ |
660 | if (!memcmp(symbol + len - 6, "_start", 6)) |
661 | return 1; |
662 | |
663 | /* __XXXXX_end */ |
664 | if (!memcmp(symbol + len - 4, "_end", 4)) |
665 | return 1; |
666 | |
667 | return 0; |
668 | } |
669 | |
670 | static int prefix_underscores_count(const char *str) |
671 | { |
672 | const char *tail = str; |
673 | |
674 | while (*tail == '_') |
675 | tail++; |
676 | |
677 | return tail - str; |
678 | } |
679 | |
680 | static int compare_symbols(const void *a, const void *b) |
681 | { |
682 | const struct sym_entry *sa; |
683 | const struct sym_entry *sb; |
684 | int wa, wb; |
685 | |
686 | sa = a; |
687 | sb = b; |
688 | |
689 | /* sort by address first */ |
690 | if (sa->addr > sb->addr) |
691 | return 1; |
692 | if (sa->addr < sb->addr) |
693 | return -1; |
694 | |
695 | /* sort by "weakness" type */ |
696 | wa = (sa->sym[0] == 'w') || (sa->sym[0] == 'W'); |
697 | wb = (sb->sym[0] == 'w') || (sb->sym[0] == 'W'); |
698 | if (wa != wb) |
699 | return wa - wb; |
700 | |
701 | /* sort by "linker script provide" type */ |
702 | wa = may_be_linker_script_provide_symbol(sa); |
703 | wb = may_be_linker_script_provide_symbol(sb); |
704 | if (wa != wb) |
705 | return wa - wb; |
706 | |
707 | /* sort by the number of prefix underscores */ |
708 | wa = prefix_underscores_count((const char *)sa->sym + 1); |
709 | wb = prefix_underscores_count((const char *)sb->sym + 1); |
710 | if (wa != wb) |
711 | return wa - wb; |
712 | |
713 | /* sort by initial order, so that other symbols are left undisturbed */ |
714 | return sa->start_pos - sb->start_pos; |
715 | } |
716 | |
717 | static void sort_symbols(void) |
718 | { |
719 | qsort(table, table_cnt, sizeof(struct sym_entry), compare_symbols); |
720 | } |
721 | |
722 | static void make_percpus_absolute(void) |
723 | { |
724 | unsigned int i; |
725 | |
726 | for (i = 0; i < table_cnt; i++) |
727 | if (symbol_in_range(&table[i], &percpu_range, 1)) { |
728 | /* |
729 | * Keep the 'A' override for percpu symbols to |
730 | * ensure consistent behavior compared to older |
731 | * versions of this tool. |
732 | */ |
733 | table[i].sym[0] = 'A'; |
734 | table[i].percpu_absolute = 1; |
735 | } |
736 | } |
737 | |
738 | /* find the minimum non-absolute symbol address */ |
739 | static void record_relative_base(void) |
740 | { |
741 | unsigned int i; |
742 | |
743 | relative_base = -1ULL; |
744 | for (i = 0; i < table_cnt; i++) |
745 | if (!symbol_absolute(&table[i]) && |
746 | table[i].addr < relative_base) |
747 | relative_base = table[i].addr; |
748 | } |
749 | |
750 | int main(int argc, char **argv) |
751 | { |
752 | if (argc >= 2) { |
753 | int i; |
754 | for (i = 1; i < argc; i++) { |
755 | if(strcmp(argv[i], "--all-symbols") == 0) |
756 | all_symbols = 1; |
757 | else if (strcmp(argv[i], "--absolute-percpu") == 0) |
758 | absolute_percpu = 1; |
759 | else if (strncmp(argv[i], "--symbol-prefix=", 16) == 0) { |
760 | char *p = &argv[i][16]; |
761 | /* skip quote */ |
762 | if ((*p == '"' && *(p+2) == '"') || (*p == '\'' && *(p+2) == '\'')) |
763 | p++; |
764 | symbol_prefix_char = *p; |
765 | } else if (strcmp(argv[i], "--base-relative") == 0) |
766 | base_relative = 1; |
767 | else |
768 | usage(); |
769 | } |
770 | } else if (argc != 1) |
771 | usage(); |
772 | |
773 | read_map(stdin); |
774 | if (absolute_percpu) |
775 | make_percpus_absolute(); |
776 | if (base_relative) |
777 | record_relative_base(); |
778 | sort_symbols(); |
779 | optimize_token_table(); |
780 | write_src(); |
781 | |
782 | return 0; |
783 | } |
784 |