elf_reloc.h

微内核软实时操作系统

/*-
 * Copyright (c) 2006, Kohsuke Ohtani
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the author nor the names of any co-contributors 
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Relocation type for arm
 */
#define	R_ARM_NONE	0
#define	R_ARM_PC24	1
#define	R_ARM_ABS32	2
#define	R_ARM_PLT32	27

static inline
int relocate_rel(Elf32_Rel *rel, Elf32_Addr sym_val, char *target_sect)
{
	Elf32_Addr *where, tmp;
	Elf32_Sword addend;

	where = (Elf32_Addr *)(target_sect + rel->r_offset);

	switch (ELF32_R_TYPE(rel->r_info)) {
	case R_ARM_NONE:
		break;
	case R_ARM_ABS32:
		*where += (Elf32_Addr)sym_val;
		/* dbg("R_ARM_ABS32: %x -> %x\n", where, *where); */
		break;
	case R_ARM_PC24:
	case R_ARM_PLT32:
		addend = *where & 0x00ffffff;
		if (addend & 0x00800000)
			addend |= 0xff000000;
		tmp = sym_val - (Elf32_Addr)where + (addend << 2);
		tmp >>= 2;
		*where = (*where & 0xff000000) | (tmp & 0x00ffffff);
		/* dbg("R_ARM_PC24: %x -> %x\n", where, *where); */
		break;
	default:
		/* dbg("relocation fail\n"); */
		return -1;
	}
	return 0;
}

static inline
int relocate_rela(Elf32_Rela *rela, Elf32_Addr sym_val, char *target_sec)
{
	/* dbg("Invalid relocation type\n"); */
	return -1;
}