diff options
| -rw-r--r-- | arch/x86/tools/relocs.c | 304 |
1 files changed, 170 insertions, 134 deletions
diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c index fd28ef7dfbb9..bdc5930b3a1b 100644 --- a/arch/x86/tools/relocs.c +++ b/arch/x86/tools/relocs.c @@ -2,6 +2,7 @@ #include <stdarg.h> #include <stdlib.h> #include <stdint.h> +#include <inttypes.h> #include <string.h> #include <errno.h> #include <unistd.h> @@ -38,10 +39,15 @@ static void die(char *fmt, ...); #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) static Elf_Ehdr ehdr; -static unsigned long reloc_count, reloc_idx; -static unsigned long *relocs; -static unsigned long reloc16_count, reloc16_idx; -static unsigned long *relocs16; + +struct relocs { + uint32_t *offset; + unsigned long count; + unsigned long size; +}; + +static struct relocs relocs16; +static struct relocs relocs32; struct section { Elf_Shdr shdr; @@ -583,8 +589,23 @@ static void print_absolute_relocs(void) printf("\n"); } -static void walk_relocs(void (*visit)(Elf_Rel *rel, Elf_Sym *sym), - int use_real_mode) +static void add_reloc(struct relocs *r, uint32_t offset) +{ + if (r->count == r->size) { + unsigned long newsize = r->size + 50000; + void *mem = realloc(r->offset, newsize * sizeof(r->offset[0])); + + if (!mem) + die("realloc of %ld entries for relocs failed\n", + newsize); + r->offset = mem; + r->size = newsize; + } + r->offset[r->count++] = offset; +} + +static void walk_relocs(int (*process)(struct section *sec, Elf_Rel *rel, + Elf_Sym *sym, const char *symname)) { int i; /* Walk through the relocations */ @@ -606,100 +627,142 @@ static void walk_relocs(void (*visit)(Elf_Rel *rel, Elf_Sym *sym), sh_symtab = sec_symtab->symtab; sym_strtab = sec_symtab->link->strtab; for (j = 0; j < sec->shdr.sh_size/sizeof(Elf_Rel); j++) { - Elf_Rel *rel; - Elf_Sym *sym; - unsigned r_type; - const char *symname; - int shn_abs; + Elf_Rel *rel = &sec->reltab[j]; + Elf_Sym *sym = &sh_symtab[ELF_R_SYM(rel->r_info)]; + const char *symname = sym_name(sym_strtab, sym); - rel = &sec->reltab[j]; - sym = &sh_symtab[ELF_R_SYM(rel->r_info)]; - r_type = ELF_R_TYPE(rel->r_info); - - shn_abs = sym->st_shndx == SHN_ABS; - - switch (r_type) { - case R_386_NONE: - case R_386_PC32: - case R_386_PC16: - case R_386_PC8: - /* - * NONE can be ignored and and PC relative - * relocations don't need to be adjusted. - */ + process(sec, rel, sym, symname); + } + } +} + +static int do_reloc(struct section *sec, Elf_Rel *rel, Elf_Sym *sym, + const char *symname) +{ + unsigned r_type = ELF32_R_TYPE(rel->r_info); + int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname); + + switch (r_type) { + case R_386_NONE: + case R_386_PC32: + case R_386_PC16: + case R_386_PC8: + /* + * NONE can be ignored and PC relative relocations don't + * need to be adjusted. + */ + break; + + case R_386_32: + if (shn_abs) { + /* + * Whitelisted absolute symbols do not require + * relocation. + */ + if (is_reloc(S_ABS, symname)) break; - case R_386_16: - symname = sym_name(sym_strtab, sym); - if (!use_real_mode) - goto bad; - if (shn_abs) { - if (is_reloc(S_ABS, symname)) - break; - else if (!is_reloc(S_SEG, symname)) - goto bad; - } else { - if (is_reloc(S_LIN, symname)) - goto bad; - else - break; - } - visit(rel, sym); + die("Invalid absolute %s relocation: %s\n", + rel_type(r_type), symname); + break; + } + + add_reloc(&relocs32, rel->r_offset); + break; + + default: + die("Unsupported relocation type: %s (%d)\n", + rel_type(r_type), r_type); + break; + } + + return 0; +} + +static int do_reloc_real(struct section *sec, Elf_Rel *rel, Elf_Sym *sym, + const char *symname) +{ + unsigned r_type = ELF32_R_TYPE(rel->r_info); + int shn_abs = (sym->st_shndx == SHN_ABS) && !is_reloc(S_REL, symname); + + switch (r_type) { + case R_386_NONE: + case R_386_PC32: + case R_386_PC16: + case R_386_PC8: + /* + * NONE can be ignored and PC relative relocations don't + * need to be adjusted. + */ + break; + + case R_386_16: + if (shn_abs) { + /* + * Whitelisted absolute symbols do not require + * relocation. + */ + if (is_reloc(S_ABS, symname)) break; - case R_386_32: - symname = sym_name(sym_strtab, sym); - if (shn_abs) { - if (is_reloc(S_ABS, symname)) - break; - else if (!is_reloc(S_REL, symname)) - goto bad; - } else { - if (use_real_mode && - !is_reloc(S_LIN, symname)) - break; - } - visit(rel, sym); + if (is_reloc(S_SEG, symname)) { + add_reloc(&relocs16, rel->r_offset); + break; + } + } else { + if (!is_reloc(S_LIN, symname)) break; - default: - die("Unsupported relocation type: %s (%d)\n", - rel_type(r_type), r_type); + } + die("Invalid %s %s relocation: %s\n", + shn_abs ? "absolute" : "relative", + rel_type(r_type), symname); + break; + + case R_386_32: + if (shn_abs) { + /* + * Whitelisted absolute symbols do not require + * relocation. + */ + if (is_reloc(S_ABS, symname)) + break; + + if (is_reloc(S_REL, symname)) { + add_reloc(&relocs32, rel->r_offset); break; - bad: - symname = sym_name(sym_strtab, sym); - die("Invalid %s %s relocation: %s\n", - shn_abs ? "absolute" : "relative", - rel_type(r_type), symname); } + } else { + if (is_reloc(S_LIN, symname)) + add_reloc(&relocs32, rel->r_offset); + break; } - } -} + die("Invalid %s %s relocation: %s\n", + shn_abs ? "absolute" : "relative", + rel_type(r_type), symname); + break; -static void count_reloc(Elf_Rel *rel, Elf_Sym *sym) -{ - if (ELF_R_TYPE(rel->r_info) == R_386_16) - reloc16_count++; - else - reloc_count++; -} + default: + die("Unsupported relocation type: %s (%d)\n", + rel_type(r_type), r_type); + break; + } -static void collect_reloc(Elf_Rel *rel, Elf_Sym *sym) -{ - /* Remember the address that needs to be adjusted. */ - if (ELF_R_TYPE(rel->r_info) == R_386_16) - relocs16[reloc16_idx++] = rel->r_offset; - else - relocs[reloc_idx++] = rel->r_offset; + return 0; } static int cmp_relocs(const void *va, const void *vb) { - const unsigned long *a, *b; + const uint32_t *a, *b; a = va; b = vb; return (*a == *b)? 0 : (*a > *b)? 1 : -1; } -static int write32(unsigned int v, FILE *f) +static void sort_relocs(struct relocs *r) +{ + qsort(r->offset, r->count, sizeof(r->offset[0]), cmp_relocs); +} + +static int write32(uint32_t v, FILE *f) { unsigned char buf[4]; @@ -707,33 +770,25 @@ static int write32(unsigned int v, FILE *f) return fwrite(buf, 1, 4, f) == 4 ? 0 : -1; } +static int write32_as_text(uint32_t v, FILE *f) +{ + return fprintf(f, "\t.long 0x%08"PRIx32"\n", v) > 0 ? 0 : -1; +} + static void emit_relocs(int as_text, int use_real_mode) { int i; - /* Count how many relocations I have and allocate space for them. */ - reloc_count = 0; - walk_relocs(count_reloc, use_real_mode); - relocs = malloc(reloc_count * sizeof(relocs[0])); - if (!relocs) { - die("malloc of %d entries for relocs failed\n", - reloc_count); - } + int (*write_reloc)(uint32_t, FILE *) = write32; - relocs16 = malloc(reloc16_count * sizeof(relocs[0])); - if (!relocs16) { - die("malloc of %d entries for relocs16 failed\n", - reloc16_count); - } /* Collect up the relocations */ - reloc_idx = 0; - walk_relocs(collect_reloc, use_real_mode); + walk_relocs(use_real_mode ? do_reloc_real : do_reloc); - if (reloc16_count && !use_real_mode) + if (relocs16.count && !use_real_mode) die("Segment relocations found but --realmode not specified\n"); /* Order the relocations for more efficient processing */ - qsort(relocs, reloc_count, sizeof(relocs[0]), cmp_relocs); - qsort(relocs16, reloc16_count, sizeof(relocs16[0]), cmp_relocs); + sort_relocs(&relocs16); + sort_relocs(&relocs32); /* Print the relocations */ if (as_text) { @@ -742,43 +797,24 @@ static void emit_relocs(int as_text, int use_real_mode) */ printf(".section \".data.reloc\",\"a\"\n"); printf(".balign 4\n"); - if (use_real_mode) { - printf("\t.long %lu\n", reloc16_count); - for (i = 0; i < reloc16_count; i++) - printf("\t.long 0x%08lx\n", relocs16[i]); - printf("\t.long %lu\n", reloc_count); - for (i = 0; i < reloc_count; i++) { - printf("\t.long 0x%08lx\n", relocs[i]); - } - } else { - /* Print a stop */ - printf("\t.long 0x%08lx\n", (unsigned long)0); - for (i = 0; i < reloc_count; i++) { - printf("\t.long 0x%08lx\n", relocs[i]); - } - } - - printf("\n"); + write_reloc = write32_as_text; } - else { - if (use_real_mode) { - write32(reloc16_count, stdout); - for (i = 0; i < reloc16_count; i++) - write32(relocs16[i], stdout); - write32(reloc_count, stdout); - - /* Now print each relocation */ - for (i = 0; i < reloc_count; i++) - write32(relocs[i], stdout); - } else { - /* Print a stop */ - write32(0, stdout); - /* Now print each relocation */ - for (i = 0; i < reloc_count; i++) { - write32(relocs[i], stdout); - } - } + if (use_real_mode) { + write_reloc(relocs16.count, stdout); + for (i = 0; i < relocs16.count; i++) + write_reloc(relocs16.offset[i], stdout); + + write_reloc(relocs32.count, stdout); + for (i = 0; i < relocs32.count; i++) + write_reloc(relocs32.offset[i], stdout); + } else { + /* Print a stop */ + write_reloc(0, stdout); + + /* Now print each relocation */ + for (i = 0; i < relocs32.count; i++) + write_reloc(relocs32.offset[i], stdout); } } |