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							- #ifndef _ASM_M32R_UACCESS_H
 
- #define _ASM_M32R_UACCESS_H
 
- /*
 
-  *  linux/include/asm-m32r/uaccess.h
 
-  *
 
-  *  M32R version.
 
-  *    Copyright (C) 2004, 2006  Hirokazu Takata <takata at linux-m32r.org>
 
-  */
 
- /*
 
-  * User space memory access functions
 
-  */
 
- #include <linux/errno.h>
 
- #include <linux/thread_info.h>
 
- #include <asm/page.h>
 
- #include <asm/setup.h>
 
- #define VERIFY_READ 0
 
- #define VERIFY_WRITE 1
 
- /*
 
-  * The fs value determines whether argument validity checking should be
 
-  * performed or not.  If get_fs() == USER_DS, checking is performed, with
 
-  * get_fs() == KERNEL_DS, checking is bypassed.
 
-  *
 
-  * For historical reasons, these macros are grossly misnamed.
 
-  */
 
- #define MAKE_MM_SEG(s)	((mm_segment_t) { (s) })
 
- #ifdef CONFIG_MMU
 
- #define KERNEL_DS	MAKE_MM_SEG(0xFFFFFFFF)
 
- #define USER_DS		MAKE_MM_SEG(PAGE_OFFSET)
 
- #define get_ds()	(KERNEL_DS)
 
- #define get_fs()	(current_thread_info()->addr_limit)
 
- #define set_fs(x)	(current_thread_info()->addr_limit = (x))
 
- #else /* not CONFIG_MMU */
 
- #define KERNEL_DS	MAKE_MM_SEG(0xFFFFFFFF)
 
- #define USER_DS		MAKE_MM_SEG(0xFFFFFFFF)
 
- #define get_ds()	(KERNEL_DS)
 
- static inline mm_segment_t get_fs(void)
 
- {
 
- 	return USER_DS;
 
- }
 
- static inline void set_fs(mm_segment_t s)
 
- {
 
- }
 
- #endif /* not CONFIG_MMU */
 
- #define segment_eq(a,b)	((a).seg == (b).seg)
 
- #define __addr_ok(addr) \
 
- 	((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))
 
- /*
 
-  * Test whether a block of memory is a valid user space address.
 
-  * Returns 0 if the range is valid, nonzero otherwise.
 
-  *
 
-  * This is equivalent to the following test:
 
-  * (u33)addr + (u33)size >= (u33)current->addr_limit.seg
 
-  *
 
-  * This needs 33-bit arithmetic. We have a carry...
 
-  */
 
- #define __range_ok(addr,size) ({					\
 
- 	unsigned long flag, roksum; 					\
 
- 	__chk_user_ptr(addr);						\
 
- 	asm ( 								\
 
- 		"	cmpu	%1, %1    ; clear cbit\n"		\
 
- 		"	addx	%1, %3    ; set cbit if overflow\n"	\
 
- 		"	subx	%0, %0\n"				\
 
- 		"	cmpu	%4, %1\n"				\
 
- 		"	subx	%0, %5\n"				\
 
- 		: "=&r" (flag), "=r" (roksum)				\
 
- 		: "1" (addr), "r" ((int)(size)), 			\
 
- 		  "r" (current_thread_info()->addr_limit.seg), "r" (0)	\
 
- 		: "cbit" );						\
 
- 	flag; })
 
- /**
 
-  * access_ok: - Checks if a user space pointer is valid
 
-  * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that
 
-  *        %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
 
-  *        to write to a block, it is always safe to read from it.
 
-  * @addr: User space pointer to start of block to check
 
-  * @size: Size of block to check
 
-  *
 
-  * Context: User context only.  This function may sleep.
 
-  *
 
-  * Checks if a pointer to a block of memory in user space is valid.
 
-  *
 
-  * Returns true (nonzero) if the memory block may be valid, false (zero)
 
-  * if it is definitely invalid.
 
-  *
 
-  * Note that, depending on architecture, this function probably just
 
-  * checks that the pointer is in the user space range - after calling
 
-  * this function, memory access functions may still return -EFAULT.
 
-  */
 
- #ifdef CONFIG_MMU
 
- #define access_ok(type,addr,size) (likely(__range_ok(addr,size) == 0))
 
- #else
 
- static inline int access_ok(int type, const void *addr, unsigned long size)
 
- {
 
- 	unsigned long val = (unsigned long)addr;
 
- 	return ((val >= memory_start) && ((val + size) < memory_end));
 
- }
 
- #endif /* CONFIG_MMU */
 
- /*
 
-  * The exception table consists of pairs of addresses: the first is the
 
-  * address of an instruction that is allowed to fault, and the second is
 
-  * the address at which the program should continue.  No registers are
 
-  * modified, so it is entirely up to the continuation code to figure out
 
-  * what to do.
 
-  *
 
-  * All the routines below use bits of fixup code that are out of line
 
-  * with the main instruction path.  This means when everything is well,
 
-  * we don't even have to jump over them.  Further, they do not intrude
 
-  * on our cache or tlb entries.
 
-  */
 
- struct exception_table_entry
 
- {
 
- 	unsigned long insn, fixup;
 
- };
 
- extern int fixup_exception(struct pt_regs *regs);
 
- /*
 
-  * These are the main single-value transfer routines.  They automatically
 
-  * use the right size if we just have the right pointer type.
 
-  *
 
-  * This gets kind of ugly. We want to return _two_ values in "get_user()"
 
-  * and yet we don't want to do any pointers, because that is too much
 
 
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