/* * sortextable.h * * Copyright 2011 - 2012 Cavium, Inc. * * Some of this code was taken out of recordmcount.h written by: * * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved. * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc. * * * Licensed under the GNU General Public License, version 2 (GPLv2). */ #undef extable_ent_size #undef compare_extable #undef do_func #undef Elf_Addr #undef Elf_Ehdr #undef Elf_Shdr #undef Elf_Rel #undef Elf_Rela #undef Elf_Sym #undef ELF_R_SYM #undef Elf_r_sym #undef ELF_R_INFO #undef Elf_r_info #undef ELF_ST_BIND #undef ELF_ST_TYPE #undef fn_ELF_R_SYM #undef fn_ELF_R_INFO #undef uint_t #undef _r #undef _w #ifdef SORTEXTABLE_64 # define extable_ent_size 16 # define compare_extable compare_extable_64 # define do_func do64 # define Elf_Addr Elf64_Addr # define Elf_Ehdr Elf64_Ehdr # define Elf_Shdr Elf64_Shdr # define Elf_Rel Elf64_Rel # define Elf_Rela Elf64_Rela # define Elf_Sym Elf64_Sym # define ELF_R_SYM ELF64_R_SYM # define Elf_r_sym Elf64_r_sym # define ELF_R_INFO ELF64_R_INFO # define Elf_r_info Elf64_r_info # define ELF_ST_BIND ELF64_ST_BIND # define ELF_ST_TYPE ELF64_ST_TYPE # define fn_ELF_R_SYM fn_ELF64_R_SYM # define fn_ELF_R_INFO fn_ELF64_R_INFO # define uint_t uint64_t # define _r r8 # define _w w8 #else # define extable_ent_size 8 # define compare_extable compare_extable_32 # define do_func do32 # define Elf_Addr Elf32_Addr # define Elf_Ehdr Elf32_Ehdr # define Elf_Shdr Elf32_Shdr # define Elf_Rel Elf32_Rel # define Elf_Rela Elf32_Rela # define Elf_Sym Elf32_Sym # define ELF_R_SYM ELF32_R_SYM # define Elf_r_sym Elf32_r_sym # define ELF_R_INFO ELF32_R_INFO # define Elf_r_info Elf32_r_info # define ELF_ST_BIND ELF32_ST_BIND # define ELF_ST_TYPE ELF32_ST_TYPE # define fn_ELF_R_SYM fn_ELF32_R_SYM # define fn_ELF_R_INFO fn_ELF32_R_INFO # define uint_t uint32_t # define _r r # define _w w #endif static int compare_extable(const void *a, const void *b) { Elf_Addr av = _r(a); Elf_Addr bv = _r(b); if (av < bv) return -1; if (av > bv) return 1; return 0; } static void do_func(Elf_Ehdr *ehdr, char const *const fname, table_sort_t custom_sort) { Elf_Shdr *shdr; Elf_Shdr *shstrtab_sec; Elf_Shdr *strtab_sec = NULL; Elf_Shdr *symtab_sec = NULL; Elf_Shdr *extab_sec = NULL; Elf_Sym *sym; const Elf_Sym *symtab; Elf32_Word *symtab_shndx_start = NULL; Elf_Sym *sort_needed_sym; Elf_Shdr *sort_needed_sec; Elf_Rel *relocs = NULL; int relocs_size = 0; uint32_t *sort_done_location; const char *secstrtab; const char *strtab; char *extab_image; int extab_index = 0; int i; int idx; unsigned int num_sections; unsigned int secindex_strings; shdr = (Elf_Shdr *)((char *)ehdr + _r(&ehdr->e_shoff)); num_sections = r2(&ehdr->e_shnum); if (num_sections == SHN_UNDEF) num_sections = _r(&shdr[0].sh_size); secindex_strings = r2(&ehdr->e_shstrndx); if (secindex_strings == SHN_XINDEX) secindex_strings = r(&shdr[0].sh_link); shstrtab_sec = shdr + secindex_strings; secstrtab = (const char *)ehdr + _r(&shstrtab_sec->sh_offset); for (i = 0; i < num_sections; i++) { idx = r(&shdr[i].sh_name); if (strcmp(secstrtab + idx, "__ex_table") == 0) { extab_sec = shdr + i; extab_index = i; } if ((r(&shdr[i].sh_type) == SHT_REL || r(&shdr[i].sh_type) == SHT_RELA) && r(&shdr[i].sh_info) == extab_index) { relocs = (void *)ehdr + _r(&shdr[i].sh_offset); relocs_size = _r(&shdr[i].sh_size); } if (strcmp(secstrtab + idx, ".symtab") == 0) symtab_sec = shdr + i; if (strcmp(secstrtab + idx, ".strtab") == 0) strtab_sec = shdr + i; if (r(&shdr[i].sh_type) == SHT_SYMTAB_SHNDX) symtab_shndx_start = (Elf32_Word *)( (const char *)ehdr + _r(&shdr[i].sh_offset)); } if (strtab_sec == NULL) { fprintf(stderr, "no .strtab in file: %s\n", fname); fail_file(); } if (symtab_sec == NULL) { fprintf(stderr, "no .symtab in file: %s\n", fname); fail_file(); } symtab = (const Elf_Sym *)((const char *)ehdr + _r(&symtab_sec->sh_offset)); if (extab_sec == NULL) { fprintf(stderr, "no __ex_table in file: %s\n", fname); fail_file(); } strtab = (const char *)ehdr + _r(&strtab_sec->sh_offset); extab_image = (void *)ehdr + _r(&extab_sec->sh_offset); if (custom_sort) { custom_sort(extab_image, _r(&extab_sec->sh_size)); } else { int num_entries = _r(&extab_sec->sh_size) / extable_ent_size; qsort(extab_image, num_entries, extable_ent_size, compare_extable); } /* If there were relocations, we no longer need them. */ if (relocs) memset(relocs, 0, relocs_size); /* find main_extable_sort_needed */ sort_needed_sym = NULL; for (i = 0; i < _r(&symtab_sec->sh_size) / sizeof(Elf_Sym); i++) { sym = (void *)ehdr + _r(&symtab_sec->sh_offset); sym += i; if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT) continue; idx = r(&sym->st_name); if (strcmp(strtab + idx, "main_extable_sort_needed") == 0) { sort_needed_sym = sym; break; } } if (sort_needed_sym == NULL) { fprintf(stderr, "no main_extable_sort_needed symbol in file: %s\n", fname); fail_file(); } sort_needed_sec = &shdr[get_secindex(r2(&sym->st_shndx), sort_needed_sym - symtab, symtab_shndx_start)]; sort_done_location = (void *)ehdr + _r(&sort_needed_sec->sh_offset) + _r(&sort_needed_sym->st_value) - _r(&sort_needed_sec->sh_addr); #if 0 printf("sort done marker at %lx\n", (unsigned long)((char *)sort_done_location - (char *)ehdr)); #endif /* We sorted it, clear the flag. */ w(0, sort_done_location); }