diff options
Diffstat (limited to 'ldso/ldso/x86_64/dl-startup.h')
-rw-r--r-- | ldso/ldso/x86_64/dl-startup.h | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/ldso/ldso/x86_64/dl-startup.h b/ldso/ldso/x86_64/dl-startup.h new file mode 100644 index 000000000..1b83e5d91 --- /dev/null +++ b/ldso/ldso/x86_64/dl-startup.h @@ -0,0 +1,69 @@ +/* vi: set sw=4 ts=4: */ +/* + * Architecture specific code used by dl-startup.c + * Copyright (C) 2000-2004 by Erik Andersen <andersen@codepoet.org> + */ +asm( + " .text\n" + " .align 16\n" + " .global _start\n" + " .type _start,%function\n" + "_start:\n" + " movq %rsp, %rdi\n" + " call _dl_start\n" + " # Save the user entry point address in %r12.\n" + " movq %rax, %r12\n" + " # See if we were run as a command with the executable file\n" + " # name as an extra leading argument.\n" + " movl _dl_skip_args(%rip), %eax\n" + " # Pop the original argument count.\n" + " popq %rdx\n" + " # Adjust the stack pointer to skip _dl_skip_args words.\n" + " leaq (%rsp,%rax,8), %rsp\n" + " # Subtract _dl_skip_args from argc.\n" + " subl %eax, %edx\n" + " # Push argc back on the stack.\n" + " pushq %rdx\n" + " # Pass our finalizer function to the user in %rdx, as per ELF ABI.\n" + " leaq _dl_fini(%rip), %rdx\n" + " # And make sure %rsp points to argc stored on the stack.\n" + " movq %r13, %rsp\n" + " # Jump to the user's entry point.\n" + " jmp *%r12\n" + " .size _start,.-_start\n" + " .previous\n" +); + +/* 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)+1) + +/* Handle relocation of the symbols in the dynamic loader. */ +static __always_inline +void PERFORM_BOOTSTRAP_RELOC(ELF_RELOC *rpnt, unsigned long *reloc_addr, + unsigned long symbol_addr, unsigned long load_addr, Elf64_Sym *sym) +{ + switch (ELF64_R_TYPE(rpnt->r_info)) { + case R_X86_64_GLOB_DAT: + case R_X86_64_JUMP_SLOT: + *reloc_addr = symbol_addr + rpnt->r_addend; + break; + case R_X86_64_DTPMOD64: + *reloc_addr = 1; + break; + case R_X86_64_NONE: + case R_X86_64_DTPOFF64: + break; + case R_X86_64_TPOFF64: + *reloc_addr = sym->st_value + rpnt->r_addend - symbol_addr; + break; + default: + _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. */ +#define START() return _dl_elf_main |