/* vi: set sw=4 ts=4: */ /* * Various assmbly language/system dependent hacks that are required * so that we can minimize the amount of platform specific code. */ /* * Define this if the system uses RELOCA. */ #undef ELF_USES_RELOCA /* * Get a pointer to the argv array. On many platforms this can be just * the address if the first argument, on other platforms we need to * do something a little more subtle here. */ #define GET_ARGV(ARGVP, ARGS) ARGVP = ((unsigned long *) ARGS) /* * Initialization sequence for the application or library GOT. */ #define INIT_GOT(GOT_BASE,MODULE) \ do { \ Elf32_Sym *sym; \ char *strtab; \ unsigned long i; \ \ /* Check if this is the dynamic linker itself */ \ if (MODULE->libtype == program_interpreter) \ continue; \ \ /* Fill in first two GOT entries according to the ABI */ \ GOT_BASE[0] = (unsigned long) _dl_linux_resolve; \ GOT_BASE[1] = (unsigned long) MODULE; \ \ /* Add load address displacement to all local GOT entries */ \ i = 2; \ while (i < MODULE->mips_local_gotno) \ GOT_BASE[i++] += (unsigned long) MODULE->loadaddr; \ \ /* Handle global GOT entries */ \ GOT_BASE += MODULE->mips_local_gotno; \ sym = (Elf32_Sym *) (MODULE->dynamic_info[DT_SYMTAB] + \ (unsigned long) MODULE->loadaddr) + MODULE->mips_gotsym; \ strtab = (char *) (MODULE->dynamic_info[DT_STRTAB] + \ (unsigned long) MODULE->loadaddr); \ i = MODULE->mips_symtabno - MODULE->mips_gotsym; \ while (i--) { \ if (sym->st_shndx == SHN_UNDEF) { \ if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC && \ sym->st_value) \ *GOT_BASE = sym->st_value + \ (unsigned long) MODULE->loadaddr; \ else { \ *GOT_BASE = (unsigned long) _dl_find_hash(strtab + \ sym->st_name, MODULE->symbol_scope, NULL, 1); \ } \ } \ else if (sym->st_shndx == SHN_COMMON) { \ *GOT_BASE = (unsigned long) _dl_find_hash(strtab + \ sym->st_name, MODULE->symbol_scope, NULL, 1); \ } \ else if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC && \ *GOT_BASE != sym->st_value) \ *GOT_BASE += (unsigned long) MODULE->loadaddr; \ else if (ELF32_ST_TYPE(sym->st_info) == STT_SECTION) { \ if (sym->st_other == 0) \ *GOT_BASE += (unsigned long) MODULE->loadaddr; \ } \ else { \ *GOT_BASE = (unsigned long) _dl_find_hash(strtab + \ sym->st_name, MODULE->symbol_scope, NULL, 1); \ } \ \ ++GOT_BASE; \ ++sym; \ } \ } while (0) /* * Here is a macro to perform the GOT relocation. This is only * used when bootstrapping the dynamic loader. */ #define PERFORM_BOOTSTRAP_GOT(got) \ do { \ Elf32_Sym *sym; \ unsigned long i; \ \ /* Add load address displacement to all local GOT entries */ \ i = 2; \ while (i < tpnt->mips_local_gotno) \ got[i++] += load_addr; \ \ /* Handle global GOT entries */ \ got += tpnt->mips_local_gotno; \ sym = (Elf32_Sym *) (tpnt->dynamic_info[DT_SYMTAB] + \ load_addr) + tpnt->mips_gotsym; \ i = tpnt->mips_symtabno - tpnt->mips_gotsym; \ \ while (i--) { \ if (sym->st_shndx == SHN_UNDEF || \ sym->st_shndx == SHN_COMMON) \ *got = load_addr + sym->st_value; \ else if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC && \ *got != sym->st_value) \ *got += load_addr; \ else if (ELF32_ST_TYPE(sym->st_info) == STT_SECTION) { \ if (sym->st_other == 0) \ *got += load_addr; \ } \ else \ *got = load_addr + sym->st_value; \ \ got++; \ sym++; \ } \ } while (0) /* * Here is a macro to perform a relocation. This is only used when * bootstrapping the dynamic loader. */ #define PERFORM_BOOTSTRAP_RELOC(RELP,REL,SYMBOL,LOAD) \ switch(ELF32_R_TYPE((RELP)->r_info)) { \ case R_MIPS_REL32: \ if (symtab_index) { \ if (symtab_index < tpnt->mips_gotsym) \ *REL += SYMBOL; \ } \ else { \ *REL += LOAD; \ } \ break; \ case R_MIPS_NONE: \ break; \ default: \ SEND_STDERR("Aiieeee!"); \ _dl_exit(1); \ } /* * Transfer control to the user's application, once the dynamic loader * is done. This routine has to exit the current function, then * call the _dl_elf_main function. For MIPS, we do it in assembly * because the stack doesn't get properly restored otherwise. Got look * at boot1_arch.h */ #define START() /* Here we define the magic numbers that this dynamic loader should accept */ #define MAGIC1 EM_MIPS #define MAGIC2 EM_MIPS_RS3_LE /* Used for error messages */ #define ELF_TARGET "MIPS" unsigned long _dl_linux_resolver(unsigned long sym_index, unsigned long old_gpreg); #define do_rem(result, n, base) result = (n % base)