Generic bug implementation for s390. Will increase the value of the console output on BUG() statements since registers r0-r5,r14 will not be clobbered by a printk() call that was previously done before the illegal instruction of BUG() was hit. Also implements an architecture specific WARN_ON(). Output of that could be increased but requires common code change. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
		
			
				
	
	
		
			408 lines
		
	
	
	
		
			13 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			408 lines
		
	
	
	
		
			13 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *  arch/s390/kernel/module.c - Kernel module help for s390.
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 *
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 *  S390 version
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 *    Copyright (C) 2002, 2003 IBM Deutschland Entwicklung GmbH,
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 *			       IBM Corporation
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 *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
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 *		 Martin Schwidefsky (schwidefsky@de.ibm.com)
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 *
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 *  based on i386 version
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 *    Copyright (C) 2001 Rusty Russell.
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 *
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 *  This program is free software; you can redistribute it and/or modify
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 *  it under the terms of the GNU General Public License as published by
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 *  the Free Software Foundation; either version 2 of the License, or
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 *  (at your option) any later version.
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 *
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 *  This program is distributed in the hope that it will be useful,
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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 *  GNU General Public License for more details.
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 *
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 *  You should have received a copy of the GNU General Public License
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 *  along with this program; if not, write to the Free Software
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 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 */
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#include <linux/module.h>
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#include <linux/elf.h>
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#include <linux/vmalloc.h>
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#include <linux/fs.h>
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#include <linux/string.h>
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#include <linux/kernel.h>
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#include <linux/moduleloader.h>
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#include <linux/bug.h>
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#if 0
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#define DEBUGP printk
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#else
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#define DEBUGP(fmt , ...)
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#endif
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#ifndef CONFIG_64BIT
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#define PLT_ENTRY_SIZE 12
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#else /* CONFIG_64BIT */
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#define PLT_ENTRY_SIZE 20
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#endif /* CONFIG_64BIT */
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void *module_alloc(unsigned long size)
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{
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	if (size == 0)
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		return NULL;
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	return vmalloc(size);
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}
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/* Free memory returned from module_alloc */
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void module_free(struct module *mod, void *module_region)
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{
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	vfree(module_region);
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	/* FIXME: If module_region == mod->init_region, trim exception
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           table entries. */
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}
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static void
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check_rela(Elf_Rela *rela, struct module *me)
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{
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	struct mod_arch_syminfo *info;
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	info = me->arch.syminfo + ELF_R_SYM (rela->r_info);
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	switch (ELF_R_TYPE (rela->r_info)) {
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	case R_390_GOT12:	/* 12 bit GOT offset.  */
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	case R_390_GOT16:	/* 16 bit GOT offset.  */
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	case R_390_GOT20:	/* 20 bit GOT offset.  */
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	case R_390_GOT32:	/* 32 bit GOT offset.  */
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	case R_390_GOT64:	/* 64 bit GOT offset.  */
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	case R_390_GOTENT:	/* 32 bit PC rel. to GOT entry shifted by 1. */
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	case R_390_GOTPLT12:	/* 12 bit offset to jump slot.	*/
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	case R_390_GOTPLT16:	/* 16 bit offset to jump slot.  */
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	case R_390_GOTPLT20:	/* 20 bit offset to jump slot.  */
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	case R_390_GOTPLT32:	/* 32 bit offset to jump slot.  */
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	case R_390_GOTPLT64:	/* 64 bit offset to jump slot.	*/
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	case R_390_GOTPLTENT:	/* 32 bit rel. offset to jump slot >> 1. */
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		if (info->got_offset == -1UL) {
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			info->got_offset = me->arch.got_size;
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			me->arch.got_size += sizeof(void*);
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		}
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		break;
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	case R_390_PLT16DBL:	/* 16 bit PC rel. PLT shifted by 1.  */
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	case R_390_PLT32DBL:	/* 32 bit PC rel. PLT shifted by 1.  */
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	case R_390_PLT32:	/* 32 bit PC relative PLT address.  */
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	case R_390_PLT64:	/* 64 bit PC relative PLT address.  */
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	case R_390_PLTOFF16:	/* 16 bit offset from GOT to PLT. */
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	case R_390_PLTOFF32:	/* 32 bit offset from GOT to PLT. */
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	case R_390_PLTOFF64:	/* 16 bit offset from GOT to PLT. */
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		if (info->plt_offset == -1UL) {
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			info->plt_offset = me->arch.plt_size;
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			me->arch.plt_size += PLT_ENTRY_SIZE;
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		}
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		break;
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	case R_390_COPY:
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	case R_390_GLOB_DAT:
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	case R_390_JMP_SLOT:
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	case R_390_RELATIVE:
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		/* Only needed if we want to support loading of 
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		   modules linked with -shared. */
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		break;
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	}
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}
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/*
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 * Account for GOT and PLT relocations. We can't add sections for
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 * got and plt but we can increase the core module size.
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 */
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int
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module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
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			  char *secstrings, struct module *me)
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{
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	Elf_Shdr *symtab;
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	Elf_Sym *symbols;
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	Elf_Rela *rela;
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	char *strings;
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	int nrela, i, j;
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	/* Find symbol table and string table. */
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	symtab = NULL;
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	for (i = 0; i < hdr->e_shnum; i++)
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		switch (sechdrs[i].sh_type) {
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		case SHT_SYMTAB:
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			symtab = sechdrs + i;
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			break;
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		}
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	if (!symtab) {
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		printk(KERN_ERR "module %s: no symbol table\n", me->name);
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		return -ENOEXEC;
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	}
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	/* Allocate one syminfo structure per symbol. */
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	me->arch.nsyms = symtab->sh_size / sizeof(Elf_Sym);
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	me->arch.syminfo = vmalloc(me->arch.nsyms *
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				   sizeof(struct mod_arch_syminfo));
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	if (!me->arch.syminfo)
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		return -ENOMEM;
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	symbols = (void *) hdr + symtab->sh_offset;
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	strings = (void *) hdr + sechdrs[symtab->sh_link].sh_offset;
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	for (i = 0; i < me->arch.nsyms; i++) {
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		if (symbols[i].st_shndx == SHN_UNDEF &&
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		    strcmp(strings + symbols[i].st_name,
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			   "_GLOBAL_OFFSET_TABLE_") == 0)
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			/* "Define" it as absolute. */
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			symbols[i].st_shndx = SHN_ABS;
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		me->arch.syminfo[i].got_offset = -1UL;
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		me->arch.syminfo[i].plt_offset = -1UL;
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		me->arch.syminfo[i].got_initialized = 0;
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		me->arch.syminfo[i].plt_initialized = 0;
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	}
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	/* Search for got/plt relocations. */
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	me->arch.got_size = me->arch.plt_size = 0;
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	for (i = 0; i < hdr->e_shnum; i++) {
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		if (sechdrs[i].sh_type != SHT_RELA)
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			continue;
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		nrela = sechdrs[i].sh_size / sizeof(Elf_Rela);
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		rela = (void *) hdr + sechdrs[i].sh_offset;
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		for (j = 0; j < nrela; j++)
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			check_rela(rela + j, me);
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	}
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	/* Increase core size by size of got & plt and set start
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	   offsets for got and plt. */
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	me->core_size = ALIGN(me->core_size, 4);
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	me->arch.got_offset = me->core_size;
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	me->core_size += me->arch.got_size;
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	me->arch.plt_offset = me->core_size;
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	me->core_size += me->arch.plt_size;
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	return 0;
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}
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int
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apply_relocate(Elf_Shdr *sechdrs, const char *strtab, unsigned int symindex,
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	       unsigned int relsec, struct module *me)
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{
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	printk(KERN_ERR "module %s: RELOCATION unsupported\n",
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	       me->name);
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	return -ENOEXEC;
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}
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static int
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apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab, 
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	   struct module *me)
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{
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	struct mod_arch_syminfo *info;
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	Elf_Addr loc, val;
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	int r_type, r_sym;
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	/* This is where to make the change */
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	loc = base + rela->r_offset;
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	/* This is the symbol it is referring to.  Note that all
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	   undefined symbols have been resolved.  */
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	r_sym = ELF_R_SYM(rela->r_info);
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	r_type = ELF_R_TYPE(rela->r_info);
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	info = me->arch.syminfo + r_sym;
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	val = symtab[r_sym].st_value;
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	switch (r_type) {
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	case R_390_8:		/* Direct 8 bit.   */
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	case R_390_12:		/* Direct 12 bit.  */
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	case R_390_16:		/* Direct 16 bit.  */
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	case R_390_20:		/* Direct 20 bit.  */
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	case R_390_32:		/* Direct 32 bit.  */
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	case R_390_64:		/* Direct 64 bit.  */
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		val += rela->r_addend;
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		if (r_type == R_390_8)
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			*(unsigned char *) loc = val;
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		else if (r_type == R_390_12)
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			*(unsigned short *) loc = (val & 0xfff) |
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				(*(unsigned short *) loc & 0xf000);
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		else if (r_type == R_390_16)
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			*(unsigned short *) loc = val;
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		else if (r_type == R_390_20)
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			*(unsigned int *) loc =
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				(*(unsigned int *) loc & 0xf00000ff) |
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				(val & 0xfff) << 16 | (val & 0xff000) >> 4;
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		else if (r_type == R_390_32)
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			*(unsigned int *) loc = val;
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		else if (r_type == R_390_64)
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			*(unsigned long *) loc = val;
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		break;
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	case R_390_PC16:	/* PC relative 16 bit.  */
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	case R_390_PC16DBL:	/* PC relative 16 bit shifted by 1.  */
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	case R_390_PC32DBL:	/* PC relative 32 bit shifted by 1.  */
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	case R_390_PC32:	/* PC relative 32 bit.  */
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	case R_390_PC64:	/* PC relative 64 bit.	*/
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		val += rela->r_addend - loc;
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		if (r_type == R_390_PC16)
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			*(unsigned short *) loc = val;
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		else if (r_type == R_390_PC16DBL)
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			*(unsigned short *) loc = val >> 1;
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		else if (r_type == R_390_PC32DBL)
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			*(unsigned int *) loc = val >> 1;
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		else if (r_type == R_390_PC32)
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			*(unsigned int *) loc = val;
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		else if (r_type == R_390_PC64)
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			*(unsigned long *) loc = val;
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		break;
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	case R_390_GOT12:	/* 12 bit GOT offset.  */
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	case R_390_GOT16:	/* 16 bit GOT offset.  */
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	case R_390_GOT20:	/* 20 bit GOT offset.  */
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	case R_390_GOT32:	/* 32 bit GOT offset.  */
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	case R_390_GOT64:	/* 64 bit GOT offset.  */
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	case R_390_GOTENT:	/* 32 bit PC rel. to GOT entry shifted by 1. */
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	case R_390_GOTPLT12:	/* 12 bit offset to jump slot.	*/
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	case R_390_GOTPLT20:	/* 20 bit offset to jump slot.  */
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	case R_390_GOTPLT16:	/* 16 bit offset to jump slot.  */
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	case R_390_GOTPLT32:	/* 32 bit offset to jump slot.  */
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	case R_390_GOTPLT64:	/* 64 bit offset to jump slot.	*/
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	case R_390_GOTPLTENT:	/* 32 bit rel. offset to jump slot >> 1. */
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		if (info->got_initialized == 0) {
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			Elf_Addr *gotent;
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			gotent = me->module_core + me->arch.got_offset +
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				info->got_offset;
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			*gotent = val;
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			info->got_initialized = 1;
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		}
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		val = info->got_offset + rela->r_addend;
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		if (r_type == R_390_GOT12 ||
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		    r_type == R_390_GOTPLT12)
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			*(unsigned short *) loc = (val & 0xfff) |
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				(*(unsigned short *) loc & 0xf000);
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		else if (r_type == R_390_GOT16 ||
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			 r_type == R_390_GOTPLT16)
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			*(unsigned short *) loc = val;
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		else if (r_type == R_390_GOT20 ||
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			 r_type == R_390_GOTPLT20)
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			*(unsigned int *) loc =
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				(*(unsigned int *) loc & 0xf00000ff) |
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				(val & 0xfff) << 16 | (val & 0xff000) >> 4;
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		else if (r_type == R_390_GOT32 ||
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			 r_type == R_390_GOTPLT32)
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			*(unsigned int *) loc = val;
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		else if (r_type == R_390_GOTENT ||
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			 r_type == R_390_GOTPLTENT)
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			*(unsigned int *) loc =
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				(val + (Elf_Addr) me->module_core - loc) >> 1;
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		else if (r_type == R_390_GOT64 ||
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			 r_type == R_390_GOTPLT64)
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			*(unsigned long *) loc = val;
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		break;
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	case R_390_PLT16DBL:	/* 16 bit PC rel. PLT shifted by 1.  */
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	case R_390_PLT32DBL:	/* 32 bit PC rel. PLT shifted by 1.  */
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	case R_390_PLT32:	/* 32 bit PC relative PLT address.  */
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	case R_390_PLT64:	/* 64 bit PC relative PLT address.  */
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	case R_390_PLTOFF16:	/* 16 bit offset from GOT to PLT. */
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	case R_390_PLTOFF32:	/* 32 bit offset from GOT to PLT. */
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	case R_390_PLTOFF64:	/* 16 bit offset from GOT to PLT. */
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		if (info->plt_initialized == 0) {
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			unsigned int *ip;
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			ip = me->module_core + me->arch.plt_offset +
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				info->plt_offset;
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#ifndef CONFIG_64BIT
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			ip[0] = 0x0d105810; /* basr 1,0; l 1,6(1); br 1 */
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			ip[1] = 0x100607f1;
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			ip[2] = val;
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#else /* CONFIG_64BIT */
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			ip[0] = 0x0d10e310; /* basr 1,0; lg 1,10(1); br 1 */
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			ip[1] = 0x100a0004;
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			ip[2] = 0x07f10000;
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			ip[3] = (unsigned int) (val >> 32);
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			ip[4] = (unsigned int) val;
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#endif /* CONFIG_64BIT */
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			info->plt_initialized = 1;
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		}
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		if (r_type == R_390_PLTOFF16 ||
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		    r_type == R_390_PLTOFF32
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		    || r_type == R_390_PLTOFF64
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			)
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			val = me->arch.plt_offset - me->arch.got_offset +
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				info->plt_offset + rela->r_addend;
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		else
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			val =  (Elf_Addr) me->module_core +
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				me->arch.plt_offset + info->plt_offset + 
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				rela->r_addend - loc;
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		if (r_type == R_390_PLT16DBL)
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			*(unsigned short *) loc = val >> 1;
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		else if (r_type == R_390_PLTOFF16)
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			*(unsigned short *) loc = val;
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		else if (r_type == R_390_PLT32DBL)
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			*(unsigned int *) loc = val >> 1;
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		else if (r_type == R_390_PLT32 ||
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			 r_type == R_390_PLTOFF32)
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			*(unsigned int *) loc = val;
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		else if (r_type == R_390_PLT64 ||
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			 r_type == R_390_PLTOFF64)
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			*(unsigned long *) loc = val;
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		break;
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	case R_390_GOTOFF16:	/* 16 bit offset to GOT.  */
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	case R_390_GOTOFF32:	/* 32 bit offset to GOT.  */
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	case R_390_GOTOFF64:	/* 64 bit offset to GOT. */
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		val = val + rela->r_addend -
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			((Elf_Addr) me->module_core + me->arch.got_offset);
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		if (r_type == R_390_GOTOFF16)
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			*(unsigned short *) loc = val;
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		else if (r_type == R_390_GOTOFF32)
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			*(unsigned int *) loc = val;
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		else if (r_type == R_390_GOTOFF64)
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			*(unsigned long *) loc = val;
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		break;
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	case R_390_GOTPC:	/* 32 bit PC relative offset to GOT. */
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	case R_390_GOTPCDBL:	/* 32 bit PC rel. off. to GOT shifted by 1. */
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		val = (Elf_Addr) me->module_core + me->arch.got_offset +
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			rela->r_addend - loc;
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		if (r_type == R_390_GOTPC)
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			*(unsigned int *) loc = val;
 | 
						|
		else if (r_type == R_390_GOTPCDBL)
 | 
						|
			*(unsigned int *) loc = val >> 1;
 | 
						|
		break;
 | 
						|
	case R_390_COPY:
 | 
						|
	case R_390_GLOB_DAT:	/* Create GOT entry.  */
 | 
						|
	case R_390_JMP_SLOT:	/* Create PLT entry.  */
 | 
						|
	case R_390_RELATIVE:	/* Adjust by program base.  */
 | 
						|
		/* Only needed if we want to support loading of 
 | 
						|
		   modules linked with -shared. */
 | 
						|
		break;
 | 
						|
	default:
 | 
						|
		printk(KERN_ERR "module %s: Unknown relocation: %u\n",
 | 
						|
		       me->name, r_type);
 | 
						|
		return -ENOEXEC;
 | 
						|
	}
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
int
 | 
						|
apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
 | 
						|
		   unsigned int symindex, unsigned int relsec,
 | 
						|
		   struct module *me)
 | 
						|
{
 | 
						|
	Elf_Addr base;
 | 
						|
	Elf_Sym *symtab;
 | 
						|
	Elf_Rela *rela;
 | 
						|
	unsigned long i, n;
 | 
						|
	int rc;
 | 
						|
 | 
						|
	DEBUGP("Applying relocate section %u to %u\n",
 | 
						|
	       relsec, sechdrs[relsec].sh_info);
 | 
						|
	base = sechdrs[sechdrs[relsec].sh_info].sh_addr;
 | 
						|
	symtab = (Elf_Sym *) sechdrs[symindex].sh_addr;
 | 
						|
	rela = (Elf_Rela *) sechdrs[relsec].sh_addr;
 | 
						|
	n = sechdrs[relsec].sh_size / sizeof(Elf_Rela);
 | 
						|
 | 
						|
	for (i = 0; i < n; i++, rela++) {
 | 
						|
		rc = apply_rela(rela, base, symtab, me);
 | 
						|
		if (rc)
 | 
						|
			return rc;
 | 
						|
	}
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
int module_finalize(const Elf_Ehdr *hdr,
 | 
						|
		    const Elf_Shdr *sechdrs,
 | 
						|
		    struct module *me)
 | 
						|
{
 | 
						|
	vfree(me->arch.syminfo);
 | 
						|
	return module_bug_finalize(hdr, sechdrs, me);
 | 
						|
}
 | 
						|
 | 
						|
void module_arch_cleanup(struct module *mod)
 | 
						|
{
 | 
						|
	module_bug_cleanup(mod);
 | 
						|
}
 |