/* Process one elf relocation with addend. */
static int
elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
    int type, int local, elf_lookup_fn lookup)
{
	Elf64_Addr *where, val;
	Elf32_Addr *where32, val32;
	Elf_Addr addr;
	Elf_Addr addend;
	Elf_Size rtype, symidx;
	const Elf_Rel *rel;
	const Elf_Rela *rela;

	switch (type) {
	case ELF_RELOC_REL:
		rel = (const Elf_Rel *)data;
		where = (Elf_Addr *) (relocbase + rel->r_offset);
		rtype = ELF_R_TYPE(rel->r_info);
		symidx = ELF_R_SYM(rel->r_info);
		/* Addend is 32 bit on 32 bit relocs */
		switch (rtype) {
		case R_X86_64_PC32:
		case R_X86_64_32S:
			addend = *(Elf32_Addr *)where;
			break;
		default:
			addend = *where;
			break;
		}
		break;
	case ELF_RELOC_RELA:
		rela = (const Elf_Rela *)data;
		where = (Elf_Addr *) (relocbase + rela->r_offset);
		addend = rela->r_addend;
		rtype = ELF_R_TYPE(rela->r_info);
		symidx = ELF_R_SYM(rela->r_info);
		break;
	default:
		panic("unknown reloc type %d\n", type);
	}

	switch (rtype) {

		case R_X86_64_NONE:	/* none */
			break;

		case R_X86_64_64:		/* S + A */
			addr = lookup(lf, symidx, 1);
			val = addr + addend;
			if (addr == 0)
				return -1;
			if (*where != val)
				*where = val;
			break;

		case R_X86_64_PC32:	/* S + A - P */
			addr = lookup(lf, symidx, 1);
			where32 = (Elf32_Addr *)where;
			val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where);
			if (addr == 0)
				return -1;
			if (*where32 != val32)
				*where32 = val32;
			break;

		case R_X86_64_32S:	/* S + A sign extend */
			addr = lookup(lf, symidx, 1);
			val32 = (Elf32_Addr)(addr + addend);
			where32 = (Elf32_Addr *)where;
			if (addr == 0)
				return -1;
			if (*where32 != val32)
				*where32 = val32;
			break;

		case R_X86_64_COPY:	/* none */
			/*
			 * There shouldn't be copy relocations in kernel
			 * objects.
			 */
			printf("kldload: unexpected R_COPY relocation\n");
			return -1;
			break;

		case R_X86_64_GLOB_DAT:	/* S */
		case R_X86_64_JMP_SLOT:	/* XXX need addend + offset */
			addr = lookup(lf, symidx, 1);
			if (addr == 0)
				return -1;
			if (*where != addr)
				*where = addr;
			break;

		case R_X86_64_RELATIVE:	/* B + A */
			addr = relocbase + addend;
			val = addr;
			if (*where != val)
				*where = val;
			break;

		default:
			printf("kldload: unexpected relocation type %ld\n",
			       rtype);
			return -1;
	}
	return(0);
}

int
elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
    elf_lookup_fn lookup)
{

	return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup));
}

int
elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
    int type, elf_lookup_fn lookup)
{

	return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup));
}