/* MN10300 Kernel module helper routines * * Copyright (C) 2007, 2008, 2009 Red Hat, Inc. All Rights Reserved. * Written by Mark Salter (msalter@redhat.com) * - Derived from arch/i386/kernel/module.c * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public Licence as published by * the Free Software Foundation; either version 2 of the Licence, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public Licence for more details. * * You should have received a copy of the GNU General Public Licence * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */#include <linux/moduleloader.h>#include <linux/elf.h>#include <linux/vmalloc.h>#include <linux/fs.h>#include <linux/string.h>#include <linux/kernel.h>#include <linux/bug.h> #if 0#define DEBUGP printk#else#define DEBUGP(fmt, ...)#endif static void reloc_put16(uint8_t *p, uint32_t val){	p[0] = val & 0xff;	p[1] = (val >> 8) & 0xff;} static void reloc_put24(uint8_t *p, uint32_t val){	reloc_put16(p, val);	p[2] = (val >> 16) & 0xff;} static void reloc_put32(uint8_t *p, uint32_t val){	reloc_put16(p, val);	reloc_put16(p+2, val >> 16);} /* * apply a RELA relocation */int apply_relocate_add(Elf32_Shdr *sechdrs,		       const char *strtab,		       unsigned int symindex,		       unsigned int relsec,		       struct module *me){	unsigned int i, sym_diff_seen = 0;	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;	Elf32_Sym *sym;	Elf32_Addr relocation, sym_diff_val = 0;	uint8_t *location;	uint32_t value; 	DEBUGP("Applying relocate section %u to %u\n",	       relsec, sechdrs[relsec].sh_info); 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {		/* this is where to make the change */		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr			+ rel[i].r_offset; 		/* this is the symbol the relocation is referring to (note that		 * all undefined symbols have been resolved by the caller) */		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr			+ ELF32_R_SYM(rel[i].r_info); 		/* this is the adjustment to be made */		relocation = sym->st_value + rel[i].r_addend; 		if (sym_diff_seen) {			switch (ELF32_R_TYPE(rel[i].r_info)) {			case R_MN10300_32:			case R_MN10300_24:			case R_MN10300_16:			case R_MN10300_8:				relocation -= sym_diff_val;				sym_diff_seen = 0;				break;			default:				printk(KERN_ERR "module %s: Unexpected SYM_DIFF relocation: %u\n",				       me->name, ELF32_R_TYPE(rel[i].r_info));				return -ENOEXEC;			}		} 		switch (ELF32_R_TYPE(rel[i].r_info)) {			/* for the first four relocation types, we simply			 * store the adjustment at the location given */		case R_MN10300_32:			reloc_put32(location, relocation);			break;		case R_MN10300_24:			reloc_put24(location, relocation);			break;		case R_MN10300_16:			reloc_put16(location, relocation);			break;		case R_MN10300_8:			*location = relocation;			break; 			/* for the next three relocation types, we write the			 * adjustment with the address subtracted over the			 * value at the location given */		case R_MN10300_PCREL32:			value = relocation - (uint32_t) location;			reloc_put32(location, value);			break;		case R_MN10300_PCREL16:			value = relocation - (uint32_t) location;			reloc_put16(location, value);			break;		case R_MN10300_PCREL8:			*location = relocation - (uint32_t) location;			break; 		case R_MN10300_SYM_DIFF:			/* This is used to adjust the next reloc as required			 * by relaxation. */			sym_diff_seen = 1;			sym_diff_val = sym->st_value;			break; 		case R_MN10300_ALIGN:			/* Just ignore the ALIGN relocs.			 * Only interesting if kernel performed relaxation. */			continue; 		default:			printk(KERN_ERR "module %s: Unknown relocation: %u\n",			       me->name, ELF32_R_TYPE(rel[i].r_info));			return -ENOEXEC;		}	}	if (sym_diff_seen) {		printk(KERN_ERR "module %s: Nothing follows SYM_DIFF relocation: %u\n",				       me->name, ELF32_R_TYPE(rel[i].r_info));		return -ENOEXEC;	}	return 0;}