diff options
Diffstat (limited to 'scripts/sorttable.h')
-rw-r--r-- | scripts/sorttable.h | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/scripts/sorttable.h b/scripts/sorttable.h new file mode 100644 index 000000000000..82589ff90e25 --- /dev/null +++ b/scripts/sorttable.h @@ -0,0 +1,210 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * sorttable.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. + */ + +#undef extable_ent_size +#undef compare_extable +#undef do_sort +#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 SORTTABLE_64 +# define extable_ent_size 16 +# define compare_extable compare_extable_64 +# define do_sort do_sort_64 +# 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_sort do_sort_32 +# 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 int do_sort(Elf_Ehdr *ehdr, + char const *const fname, + table_sort_t custom_sort) +{ + Elf_Shdr *s, *shdr = (Elf_Shdr *)((char *)ehdr + _r(&ehdr->e_shoff)); + 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 = NULL; + Elf_Sym *sort_needed_sym = NULL; + Elf_Shdr *sort_needed_sec; + Elf_Rel *relocs = NULL; + int relocs_size = 0; + uint32_t *sort_needed_loc; + const char *secstrings; + const char *strtab; + char *extab_image; + int extab_index = 0; + int i; + int idx; + unsigned int shnum; + unsigned int shstrndx; + + shstrndx = r2(&ehdr->e_shstrndx); + if (shstrndx == SHN_XINDEX) + shstrndx = r(&shdr[0].sh_link); + secstrings = (const char *)ehdr + _r(&shdr[shstrndx].sh_offset); + + shnum = r2(&ehdr->e_shnum); + if (shnum == SHN_UNDEF) + shnum = _r(&shdr[0].sh_size); + + for (i = 0, s = shdr; s < shdr + shnum; i++, s++) { + idx = r(&s->sh_name); + if (!strcmp(secstrings + idx, "__ex_table")) { + extab_sec = s; + extab_index = i; + } + if (!strcmp(secstrings + idx, ".symtab")) + symtab_sec = s; + if (!strcmp(secstrings + idx, ".strtab")) + strtab_sec = s; + + if ((r(&s->sh_type) == SHT_REL || + r(&s->sh_type) == SHT_RELA) && + r(&s->sh_info) == extab_index) { + relocs = (void *)ehdr + _r(&s->sh_offset); + relocs_size = _r(&s->sh_size); + } + if (r(&s->sh_type) == SHT_SYMTAB_SHNDX) + symtab_shndx = (Elf32_Word *)((const char *)ehdr + + _r(&s->sh_offset)); + } + + if (!extab_sec) { + fprintf(stderr, "no __ex_table in file: %s\n", fname); + return -1; + } + + if (!symtab_sec) { + fprintf(stderr, "no .symtab in file: %s\n", fname); + return -1; + } + + if (!strtab_sec) { + fprintf(stderr, "no .strtab in file: %s\n", fname); + return -1; + } + + extab_image = (void *)ehdr + _r(&extab_sec->sh_offset); + strtab = (const char *)ehdr + _r(&strtab_sec->sh_offset); + symtab = (const Elf_Sym *)((const char *)ehdr + + _r(&symtab_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 the flag main_extable_sort_needed */ + for (sym = (void *)ehdr + _r(&symtab_sec->sh_offset); + sym < sym + _r(&symtab_sec->sh_size) / sizeof(Elf_Sym); + sym++) { + if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT) + continue; + if (!strcmp(strtab + r(&sym->st_name), + "main_extable_sort_needed")) { + sort_needed_sym = sym; + break; + } + } + + if (!sort_needed_sym) { + fprintf(stderr, + "no main_extable_sort_needed symbol in file: %s\n", + fname); + return -1; + } + + sort_needed_sec = &shdr[get_secindex(r2(&sym->st_shndx), + sort_needed_sym - symtab, + symtab_shndx)]; + sort_needed_loc = (void *)ehdr + + _r(&sort_needed_sec->sh_offset) + + _r(&sort_needed_sym->st_value) - + _r(&sort_needed_sec->sh_addr); + + /* extable has been sorted, clear the flag */ + w(0, sort_needed_loc); + + return 0; +} |