diff options
Diffstat (limited to 'ANDROID_3.4.5/scripts/kallsyms.c')
| -rw-r--r-- | ANDROID_3.4.5/scripts/kallsyms.c | 661 |
1 files changed, 0 insertions, 661 deletions
diff --git a/ANDROID_3.4.5/scripts/kallsyms.c b/ANDROID_3.4.5/scripts/kallsyms.c deleted file mode 100644 index 487ac6f3..00000000 --- a/ANDROID_3.4.5/scripts/kallsyms.c +++ /dev/null @@ -1,661 +0,0 @@ -/* Generate assembler source containing symbol information - * - * Copyright 2002 by Kai Germaschewski - * - * This software may be used and distributed according to the terms - * of the GNU General Public License, incorporated herein by reference. - * - * Usage: nm -n vmlinux | scripts/kallsyms [--all-symbols] > symbols.S - * - * Table compression uses all the unused char codes on the symbols and - * maps these to the most used substrings (tokens). For instance, it might - * map char code 0xF7 to represent "write_" and then in every symbol where - * "write_" appears it can be replaced by 0xF7, saving 5 bytes. - * The used codes themselves are also placed in the table so that the - * decompresion can work without "special cases". - * Applied to kernel symbols, this usually produces a compression ratio - * of about 50%. - * - */ - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <ctype.h> - -#ifndef ARRAY_SIZE -#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0])) -#endif - -#define KSYM_NAME_LEN 128 - -struct sym_entry { - unsigned long long addr; - unsigned int len; - unsigned int start_pos; - unsigned char *sym; -}; - -struct text_range { - const char *stext, *etext; - unsigned long long start, end; -}; - -static unsigned long long _text; -static struct text_range text_ranges[] = { - { "_stext", "_etext" }, - { "_sinittext", "_einittext" }, - { "_stext_l1", "_etext_l1" }, /* Blackfin on-chip L1 inst SRAM */ - { "_stext_l2", "_etext_l2" }, /* Blackfin on-chip L2 SRAM */ -}; -#define text_range_text (&text_ranges[0]) -#define text_range_inittext (&text_ranges[1]) - -static struct sym_entry *table; -static unsigned int table_size, table_cnt; -static int all_symbols = 0; -static char symbol_prefix_char = '\0'; - -int token_profit[0x10000]; - -/* the table that holds the result of the compression */ -unsigned char best_table[256][2]; -unsigned char best_table_len[256]; - - -static void usage(void) -{ - fprintf(stderr, "Usage: kallsyms [--all-symbols] [--symbol-prefix=<prefix char>] < in.map > out.S\n"); - exit(1); -} - -/* - * This ignores the intensely annoying "mapping symbols" found - * in ARM ELF files: $a, $t and $d. - */ -static inline int is_arm_mapping_symbol(const char *str) -{ - return str[0] == '$' && strchr("atd", str[1]) - && (str[2] == '\0' || str[2] == '.'); -} - -static int read_symbol_tr(const char *sym, unsigned long long addr) -{ - size_t i; - struct text_range *tr; - - for (i = 0; i < ARRAY_SIZE(text_ranges); ++i) { - tr = &text_ranges[i]; - - if (strcmp(sym, tr->stext) == 0) { - tr->start = addr; - return 0; - } else if (strcmp(sym, tr->etext) == 0) { - tr->end = addr; - return 0; - } - } - - return 1; -} - -static int read_symbol(FILE *in, struct sym_entry *s) -{ - char str[500]; - char *sym, stype; - int rc; - - rc = fscanf(in, "%llx %c %499s\n", &s->addr, &stype, str); - if (rc != 3) { - if (rc != EOF && fgets(str, 500, in) == NULL) - fprintf(stderr, "Read error or end of file.\n"); - return -1; - } - - sym = str; - /* skip prefix char */ - if (symbol_prefix_char && str[0] == symbol_prefix_char) - sym++; - - /* Ignore most absolute/undefined (?) symbols. */ - if (strcmp(sym, "_text") == 0) - _text = s->addr; - else if (read_symbol_tr(sym, s->addr) == 0) - /* nothing to do */; - else if (toupper(stype) == 'A') - { - /* Keep these useful absolute symbols */ - if (strcmp(sym, "__kernel_syscall_via_break") && - strcmp(sym, "__kernel_syscall_via_epc") && - strcmp(sym, "__kernel_sigtramp") && - strcmp(sym, "__gp")) - return -1; - - } - else if (toupper(stype) == 'U' || - is_arm_mapping_symbol(sym)) - return -1; - /* exclude also MIPS ELF local symbols ($L123 instead of .L123) */ - else if (str[0] == '$') - return -1; - /* exclude debugging symbols */ - else if (stype == 'N') - return -1; - - /* include the type field in the symbol name, so that it gets - * compressed together */ - s->len = strlen(str) + 1; - s->sym = malloc(s->len + 1); - if (!s->sym) { - fprintf(stderr, "kallsyms failure: " - "unable to allocate required amount of memory\n"); - exit(EXIT_FAILURE); - } - strcpy((char *)s->sym + 1, str); - s->sym[0] = stype; - - return 0; -} - -static int symbol_valid_tr(struct sym_entry *s) -{ - size_t i; - struct text_range *tr; - - for (i = 0; i < ARRAY_SIZE(text_ranges); ++i) { - tr = &text_ranges[i]; - - if (s->addr >= tr->start && s->addr <= tr->end) - return 1; - } - - return 0; -} - -static int symbol_valid(struct sym_entry *s) -{ - /* Symbols which vary between passes. Passes 1 and 2 must have - * identical symbol lists. The kallsyms_* symbols below are only added - * after pass 1, they would be included in pass 2 when --all-symbols is - * specified so exclude them to get a stable symbol list. - */ - static char *special_symbols[] = { - "kallsyms_addresses", - "kallsyms_num_syms", - "kallsyms_names", - "kallsyms_markers", - "kallsyms_token_table", - "kallsyms_token_index", - - /* Exclude linker generated symbols which vary between passes */ - "_SDA_BASE_", /* ppc */ - "_SDA2_BASE_", /* ppc */ - NULL }; - int i; - int offset = 1; - - /* skip prefix char */ - if (symbol_prefix_char && *(s->sym + 1) == symbol_prefix_char) - offset++; - - /* if --all-symbols is not specified, then symbols outside the text - * and inittext sections are discarded */ - if (!all_symbols) { - if (symbol_valid_tr(s) == 0) - return 0; - /* Corner case. Discard any symbols with the same value as - * _etext _einittext; they can move between pass 1 and 2 when - * the kallsyms data are added. If these symbols move then - * they may get dropped in pass 2, which breaks the kallsyms - * rules. - */ - if ((s->addr == text_range_text->end && - strcmp((char *)s->sym + offset, text_range_text->etext)) || - (s->addr == text_range_inittext->end && - strcmp((char *)s->sym + offset, text_range_inittext->etext))) - return 0; - } - - /* Exclude symbols which vary between passes. */ - if (strstr((char *)s->sym + offset, "_compiled.")) - return 0; - - for (i = 0; special_symbols[i]; i++) - if( strcmp((char *)s->sym + offset, special_symbols[i]) == 0 ) - return 0; - - return 1; -} - -static void read_map(FILE *in) -{ - while (!feof(in)) { - if (table_cnt >= table_size) { - table_size += 10000; - table = realloc(table, sizeof(*table) * table_size); - if (!table) { - fprintf(stderr, "out of memory\n"); - exit (1); - } - } - if (read_symbol(in, &table[table_cnt]) == 0) { - table[table_cnt].start_pos = table_cnt; - table_cnt++; - } - } -} - -static void output_label(char *label) -{ - if (symbol_prefix_char) - printf(".globl %c%s\n", symbol_prefix_char, label); - else - printf(".globl %s\n", label); - printf("\tALGN\n"); - if (symbol_prefix_char) - printf("%c%s:\n", symbol_prefix_char, label); - else - printf("%s:\n", label); -} - -/* uncompress a compressed symbol. When this function is called, the best table - * might still be compressed itself, so the function needs to be recursive */ -static int expand_symbol(unsigned char *data, int len, char *result) -{ - int c, rlen, total=0; - - while (len) { - c = *data; - /* if the table holds a single char that is the same as the one - * we are looking for, then end the search */ - if (best_table[c][0]==c && best_table_len[c]==1) { - *result++ = c; - total++; - } else { - /* if not, recurse and expand */ - rlen = expand_symbol(best_table[c], best_table_len[c], result); - total += rlen; - result += rlen; - } - data++; - len--; - } - *result=0; - - return total; -} - -static void write_src(void) -{ - unsigned int i, k, off; - unsigned int best_idx[256]; - unsigned int *markers; - char buf[KSYM_NAME_LEN]; - - printf("#include <asm/types.h>\n"); - printf("#if BITS_PER_LONG == 64\n"); - printf("#define PTR .quad\n"); - printf("#define ALGN .align 8\n"); - printf("#else\n"); - printf("#define PTR .long\n"); - printf("#define ALGN .align 4\n"); - printf("#endif\n"); - - printf("\t.section .rodata, \"a\"\n"); - - /* Provide proper symbols relocatability by their '_text' - * relativeness. The symbol names cannot be used to construct - * normal symbol references as the list of symbols contains - * symbols that are declared static and are private to their - * .o files. This prevents .tmp_kallsyms.o or any other - * object from referencing them. - */ - output_label("kallsyms_addresses"); - for (i = 0; i < table_cnt; i++) { - if (toupper(table[i].sym[0]) != 'A') { - if (_text <= table[i].addr) - printf("\tPTR\t_text + %#llx\n", - table[i].addr - _text); - else - printf("\tPTR\t_text - %#llx\n", - _text - table[i].addr); - } else { - printf("\tPTR\t%#llx\n", table[i].addr); - } - } - printf("\n"); - - output_label("kallsyms_num_syms"); - printf("\tPTR\t%d\n", table_cnt); - printf("\n"); - - /* table of offset markers, that give the offset in the compressed stream - * every 256 symbols */ - markers = malloc(sizeof(unsigned int) * ((table_cnt + 255) / 256)); - if (!markers) { - fprintf(stderr, "kallsyms failure: " - "unable to allocate required memory\n"); - exit(EXIT_FAILURE); - } - - output_label("kallsyms_names"); - off = 0; - for (i = 0; i < table_cnt; i++) { - if ((i & 0xFF) == 0) - markers[i >> 8] = off; - - printf("\t.byte 0x%02x", table[i].len); - for (k = 0; k < table[i].len; k++) - printf(", 0x%02x", table[i].sym[k]); - printf("\n"); - - off += table[i].len + 1; - } - printf("\n"); - - output_label("kallsyms_markers"); - for (i = 0; i < ((table_cnt + 255) >> 8); i++) - printf("\tPTR\t%d\n", markers[i]); - printf("\n"); - - free(markers); - - output_label("kallsyms_token_table"); - off = 0; - for (i = 0; i < 256; i++) { - best_idx[i] = off; - expand_symbol(best_table[i], best_table_len[i], buf); - printf("\t.asciz\t\"%s\"\n", buf); - off += strlen(buf) + 1; - } - printf("\n"); - - output_label("kallsyms_token_index"); - for (i = 0; i < 256; i++) - printf("\t.short\t%d\n", best_idx[i]); - printf("\n"); -} - - -/* table lookup compression functions */ - -/* count all the possible tokens in a symbol */ -static void learn_symbol(unsigned char *symbol, int len) -{ - int i; - - for (i = 0; i < len - 1; i++) - token_profit[ symbol[i] + (symbol[i + 1] << 8) ]++; -} - -/* decrease the count for all the possible tokens in a symbol */ -static void forget_symbol(unsigned char *symbol, int len) -{ - int i; - - for (i = 0; i < len - 1; i++) - token_profit[ symbol[i] + (symbol[i + 1] << 8) ]--; -} - -/* remove all the invalid symbols from the table and do the initial token count */ -static void build_initial_tok_table(void) -{ - unsigned int i, pos; - - pos = 0; - for (i = 0; i < table_cnt; i++) { - if ( symbol_valid(&table[i]) ) { - if (pos != i) - table[pos] = table[i]; - learn_symbol(table[pos].sym, table[pos].len); - pos++; - } - } - table_cnt = pos; -} - -static void *find_token(unsigned char *str, int len, unsigned char *token) -{ - int i; - - for (i = 0; i < len - 1; i++) { - if (str[i] == token[0] && str[i+1] == token[1]) - return &str[i]; - } - return NULL; -} - -/* replace a given token in all the valid symbols. Use the sampled symbols - * to update the counts */ -static void compress_symbols(unsigned char *str, int idx) -{ - unsigned int i, len, size; - unsigned char *p1, *p2; - - for (i = 0; i < table_cnt; i++) { - - len = table[i].len; - p1 = table[i].sym; - - /* find the token on the symbol */ - p2 = find_token(p1, len, str); - if (!p2) continue; - - /* decrease the counts for this symbol's tokens */ - forget_symbol(table[i].sym, len); - - size = len; - - do { - *p2 = idx; - p2++; - size -= (p2 - p1); - memmove(p2, p2 + 1, size); - p1 = p2; - len--; - - if (size < 2) break; - - /* find the token on the symbol */ - p2 = find_token(p1, size, str); - - } while (p2); - - table[i].len = len; - - /* increase the counts for this symbol's new tokens */ - learn_symbol(table[i].sym, len); - } -} - -/* search the token with the maximum profit */ -static int find_best_token(void) -{ - int i, best, bestprofit; - - bestprofit=-10000; - best = 0; - - for (i = 0; i < 0x10000; i++) { - if (token_profit[i] > bestprofit) { - best = i; - bestprofit = token_profit[i]; - } - } - return best; -} - -/* this is the core of the algorithm: calculate the "best" table */ -static void optimize_result(void) -{ - int i, best; - - /* using the '\0' symbol last allows compress_symbols to use standard - * fast string functions */ - for (i = 255; i >= 0; i--) { - - /* if this table slot is empty (it is not used by an actual - * original char code */ - if (!best_table_len[i]) { - - /* find the token with the breates profit value */ - best = find_best_token(); - if (token_profit[best] == 0) - break; - - /* place it in the "best" table */ - best_table_len[i] = 2; - best_table[i][0] = best & 0xFF; - best_table[i][1] = (best >> 8) & 0xFF; - - /* replace this token in all the valid symbols */ - compress_symbols(best_table[i], i); - } - } -} - -/* start by placing the symbols that are actually used on the table */ -static void insert_real_symbols_in_table(void) -{ - unsigned int i, j, c; - - memset(best_table, 0, sizeof(best_table)); - memset(best_table_len, 0, sizeof(best_table_len)); - - for (i = 0; i < table_cnt; i++) { - for (j = 0; j < table[i].len; j++) { - c = table[i].sym[j]; - best_table[c][0]=c; - best_table_len[c]=1; - } - } -} - -static void optimize_token_table(void) -{ - build_initial_tok_table(); - - insert_real_symbols_in_table(); - - /* When valid symbol is not registered, exit to error */ - if (!table_cnt) { - fprintf(stderr, "No valid symbol.\n"); - exit(1); - } - - optimize_result(); -} - -/* guess for "linker script provide" symbol */ -static int may_be_linker_script_provide_symbol(const struct sym_entry *se) -{ - const char *symbol = (char *)se->sym + 1; - int len = se->len - 1; - - if (len < 8) - return 0; - - if (symbol[0] != '_' || symbol[1] != '_') - return 0; - - /* __start_XXXXX */ - if (!memcmp(symbol + 2, "start_", 6)) - return 1; - - /* __stop_XXXXX */ - if (!memcmp(symbol + 2, "stop_", 5)) - return 1; - - /* __end_XXXXX */ - if (!memcmp(symbol + 2, "end_", 4)) - return 1; - - /* __XXXXX_start */ - if (!memcmp(symbol + len - 6, "_start", 6)) - return 1; - - /* __XXXXX_end */ - if (!memcmp(symbol + len - 4, "_end", 4)) - return 1; - - return 0; -} - -static int prefix_underscores_count(const char *str) -{ - const char *tail = str; - - while (*tail == '_') - tail++; - - return tail - str; -} - -static int compare_symbols(const void *a, const void *b) -{ - const struct sym_entry *sa; - const struct sym_entry *sb; - int wa, wb; - - sa = a; - sb = b; - - /* sort by address first */ - if (sa->addr > sb->addr) - return 1; - if (sa->addr < sb->addr) - return -1; - - /* sort by "weakness" type */ - wa = (sa->sym[0] == 'w') || (sa->sym[0] == 'W'); - wb = (sb->sym[0] == 'w') || (sb->sym[0] == 'W'); - if (wa != wb) - return wa - wb; - - /* sort by "linker script provide" type */ - wa = may_be_linker_script_provide_symbol(sa); - wb = may_be_linker_script_provide_symbol(sb); - if (wa != wb) - return wa - wb; - - /* sort by the number of prefix underscores */ - wa = prefix_underscores_count((const char *)sa->sym + 1); - wb = prefix_underscores_count((const char *)sb->sym + 1); - if (wa != wb) - return wa - wb; - - /* sort by initial order, so that other symbols are left undisturbed */ - return sa->start_pos - sb->start_pos; -} - -static void sort_symbols(void) -{ - qsort(table, table_cnt, sizeof(struct sym_entry), compare_symbols); -} - -int main(int argc, char **argv) -{ - if (argc >= 2) { - int i; - for (i = 1; i < argc; i++) { - if(strcmp(argv[i], "--all-symbols") == 0) - all_symbols = 1; - else if (strncmp(argv[i], "--symbol-prefix=", 16) == 0) { - char *p = &argv[i][16]; - /* skip quote */ - if ((*p == '"' && *(p+2) == '"') || (*p == '\'' && *(p+2) == '\'')) - p++; - symbol_prefix_char = *p; - } else - usage(); - } - } else if (argc != 1) - usage(); - - read_map(stdin); - sort_symbols(); - optimize_token_table(); - write_src(); - - return 0; -} |