 786d35d45c
			
		
	
	
	786d35d45c
	
	
	
		
			
			Use the mapping of Elf_[SPE]hdr, Elf_Addr, Elf_Sym, Elf_Dyn, Elf_Rel/Rela,
ELF_R_TYPE() and ELF_R_SYM() to either the 32-bit version or the 64-bit version
into asm-generic/module.h for all arches bar MIPS.
Also, use the generic definition mod_arch_specific where possible.
To this end, I've defined three new config bools:
 (*) HAVE_MOD_ARCH_SPECIFIC
     Arches define this if they don't want to use the empty generic
     mod_arch_specific struct.
 (*) MODULES_USE_ELF_RELA
     Arches define this if their modules can contain RELA records.  This causes
     the Elf_Rela mapping to be emitted and allows apply_relocate_add() to be
     defined by the arch rather than have the core emit an error message.
 (*) MODULES_USE_ELF_REL
     Arches define this if their modules can contain REL records.  This causes
     the Elf_Rel mapping to be emitted and allows apply_relocate() to be
     defined by the arch rather than have the core emit an error message.
Note that it is possible to allow both REL and RELA records: m68k and mips are
two arches that do this.
With this, some arch asm/module.h files can be deleted entirely and replaced
with a generic-y marker in the arch Kbuild file.
Additionally, I have removed the bits from m32r and score that handle the
unsupported type of relocation record as that's now handled centrally.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
		
	
			
		
			
				
	
	
		
			203 lines
		
	
	
	
		
			6.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			203 lines
		
	
	
	
		
			6.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*  Kernel module help for M32R.
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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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| 
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| #include <linux/moduleloader.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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| 
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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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| 
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| #define COPY_UNALIGNED_WORD(sw, tw, align) \
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| { \
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| 	void *__s = &(sw), *__t = &(tw); \
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| 	unsigned short *__s2 = __s, *__t2 =__t; \
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| 	unsigned char *__s1 = __s, *__t1 =__t; \
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| 	switch ((align)) \
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| 	{ \
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| 	case 0: \
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| 		*(unsigned long *) __t = *(unsigned long *) __s; \
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| 		break; \
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| 	case 2: \
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| 		*__t2++ = *__s2++; \
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| 		*__t2 = *__s2; \
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| 		break; \
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| 	default: \
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| 		*__t1++ = *__s1++; \
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| 		*__t1++ = *__s1++; \
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| 		*__t1++ = *__s1++; \
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| 		*__t1 = *__s1; \
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| 		break; \
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| 	} \
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| }
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| 
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| #define COPY_UNALIGNED_HWORD(sw, tw, align) \
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|   { \
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|     void *__s = &(sw), *__t = &(tw); \
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|     unsigned short *__s2 = __s, *__t2 =__t; \
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|     unsigned char *__s1 = __s, *__t1 =__t; \
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|     switch ((align)) \
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|     { \
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|     case 0: \
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|       *__t2 = *__s2; \
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|       break; \
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|     default: \
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|       *__t1++ = *__s1++; \
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|       *__t1 = *__s1; \
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|       break; \
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|     } \
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|   }
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| 
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| int apply_relocate_add(Elf32_Shdr *sechdrs,
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| 		   const char *strtab,
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| 		   unsigned int symindex,
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| 		   unsigned int relsec,
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| 		   struct module *me)
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| {
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| 	unsigned int i;
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| 	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
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| 	Elf32_Sym *sym;
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| 	Elf32_Addr relocation;
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| 	uint32_t *location;
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| 	uint32_t value;
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| 	unsigned short *hlocation;
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| 	unsigned short hvalue;
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| 	int svalue;
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| 	int align;
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| 
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| 	DEBUGP("Applying relocate section %u to %u\n", relsec,
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| 	       sechdrs[relsec].sh_info);
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| 	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
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| 		/* This is where to make the change */
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| 		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
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| 			+ rel[i].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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| 		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
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| 			+ ELF32_R_SYM(rel[i].r_info);
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| 		relocation = sym->st_value + rel[i].r_addend;
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| 		align = (int)location & 3;
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| 
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| 		switch (ELF32_R_TYPE(rel[i].r_info)) {
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| 		case R_M32R_32_RELA:
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| 	    		COPY_UNALIGNED_WORD (*location, value, align);
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| 			value += relocation;
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| 	    		COPY_UNALIGNED_WORD (value, *location, align);
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| 			break;
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| 		case R_M32R_HI16_ULO_RELA:
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| 	    		COPY_UNALIGNED_WORD (*location, value, align);
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|                         relocation = (relocation >>16) & 0xffff;
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| 			/* RELA must has 0 at relocation field. */
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| 			value += relocation;
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| 	    		COPY_UNALIGNED_WORD (value, *location, align);
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| 			break;
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| 		case R_M32R_HI16_SLO_RELA:
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| 	    		COPY_UNALIGNED_WORD (*location, value, align);
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| 			if (relocation & 0x8000) relocation += 0x10000;
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|                         relocation = (relocation >>16) & 0xffff;
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| 			/* RELA must has 0 at relocation field. */
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| 			value += relocation;
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| 	    		COPY_UNALIGNED_WORD (value, *location, align);
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| 			break;
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| 		case R_M32R_16_RELA:
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| 			hlocation = (unsigned short *)location;
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|                         relocation = relocation & 0xffff;
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| 			/* RELA must has 0 at relocation field. */
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| 			hvalue = relocation;
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| 	    		COPY_UNALIGNED_WORD (hvalue, *hlocation, align);
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| 			break;
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| 		case R_M32R_SDA16_RELA:
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| 		case R_M32R_LO16_RELA:
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| 	    		COPY_UNALIGNED_WORD (*location, value, align);
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|                         relocation = relocation & 0xffff;
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| 			/* RELA must has 0 at relocation field. */
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| 			value += relocation;
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| 	    		COPY_UNALIGNED_WORD (value, *location, align);
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| 			break;
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| 		case R_M32R_24_RELA:
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| 	    		COPY_UNALIGNED_WORD (*location, value, align);
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|                         relocation = relocation & 0xffffff;
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| 			/* RELA must has 0 at relocation field. */
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| 			value += relocation;
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| 	    		COPY_UNALIGNED_WORD (value, *location, align);
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| 			break;
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| 		case R_M32R_18_PCREL_RELA:
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| 	  		relocation = (relocation - (Elf32_Addr) location);
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| 			if (relocation < -0x20000 || 0x1fffc < relocation)
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| 				{
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| 					printk(KERN_ERR "module %s: relocation overflow: %u\n",
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| 					me->name, relocation);
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| 					return -ENOEXEC;
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| 				}
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| 	    		COPY_UNALIGNED_WORD (*location, value, align);
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| 			if (value & 0xffff)
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| 				{
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| 					/* RELA must has 0 at relocation field. */
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| 					printk(KERN_ERR "module %s: illegal relocation field: %u\n",
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| 					me->name, value);
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| 					return -ENOEXEC;
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| 				}
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|                         relocation = (relocation >> 2) & 0xffff;
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| 			value += relocation;
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| 	    		COPY_UNALIGNED_WORD (value, *location, align);
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| 			break;
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| 		case R_M32R_10_PCREL_RELA:
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| 			hlocation = (unsigned short *)location;
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| 	  		relocation = (relocation - (Elf32_Addr) location);
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| 	    		COPY_UNALIGNED_HWORD (*hlocation, hvalue, align);
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| 			svalue = (int)hvalue;
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| 			svalue = (signed char)svalue << 2;
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| 			relocation += svalue;
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|                         relocation = (relocation >> 2) & 0xff;
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| 			hvalue = hvalue & 0xff00;
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| 			hvalue += relocation;
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| 	    		COPY_UNALIGNED_HWORD (hvalue, *hlocation, align);
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| 			break;
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| 		case R_M32R_26_PCREL_RELA:
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| 	  		relocation = (relocation - (Elf32_Addr) location);
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| 			if (relocation < -0x2000000 || 0x1fffffc < relocation)
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| 				{
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| 					printk(KERN_ERR "module %s: relocation overflow: %u\n",
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| 					me->name, relocation);
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| 					return -ENOEXEC;
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| 				}
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| 	    		COPY_UNALIGNED_WORD (*location, value, align);
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| 			if (value & 0xffffff)
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| 				{
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| 					/* RELA must has 0 at relocation field. */
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| 					printk(KERN_ERR "module %s: illegal relocation field: %u\n",
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| 					me->name, value);
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| 					return -ENOEXEC;
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| 				}
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|                         relocation = (relocation >> 2) & 0xffffff;
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| 			value += relocation;
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| 	    		COPY_UNALIGNED_WORD (value, *location, align);
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| 			break;
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| 		default:
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| 			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
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| 			       me->name, ELF32_R_TYPE(rel[i].r_info));
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| 			return -ENOEXEC;
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| 		}
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| 	}
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| 	return 0;
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| }
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