| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268 | #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))#elsestatic 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 * of a performance impact. Thus we have a few rather ugly macros here, * and hide all the uglyness from the user. * * The "__xxx" versions of the user access functions are versions that * do not verify the address space, that must have been done previously * with a separate "access_ok()" call (this is used when we do multiple * accesses to the same area of user memory). *//* Careful: we have to cast the result to the type of the pointer for sign   reasons *//** * get_user: - Get a simple variable from user space. * @x:   Variable to store result. * @ptr: Source address, in user space. * * Context: User context only.  This function may sleep. * * This macro copies a single simple variable from user space to kernel * space.  It supports simple types like char and int, but not larger * data types like structures or arrays. * * @ptr must have pointer-to-simple-variable type, and the result of * dereferencing @ptr must be assignable to @x without a cast. * * Returns zero on success, or -EFAULT on error. * On error, the variable @x is set to zero. */#define get_user(x,ptr)							\	__get_user_check((x),(ptr),sizeof(*(ptr)))/** * put_user: - Write a simple value into user space. * @x:   Value to copy to user space. * @ptr: Destination address, in user space. * * Context: User context only.  This function may sleep. * * This macro copies a single simple value from kernel space to user * space.  It supports simple types like char and int, but not larger * data types like structures or arrays. * * @ptr must have pointer-to-simple-variable type, and @x must be assignable * to the result of dereferencing @ptr. * * Returns zero on success, or -EFAULT on error. */#define put_user(x,ptr)							\	__put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))/** * __get_user: - Get a simple variable from user space, with less checking. * @x:   Variable to store result. * @ptr: Source address, in user space. * * Context: User context only.  This function may sleep. * * This macro copies a single simple variable from user space to kernel * space.  It supports simple types like char and int, but not larger * data types like structures or arrays. * * @ptr must have pointer-to-simple-variable type, and the result of * dereferencing @ptr must be assignable to @x without a cast. * * Caller must check the pointer with access_ok() before calling this * function. * * Returns zero on success, or -EFAULT on error. * On error, the variable @x is set to zero. */#define __get_user(x,ptr) \	__get_user_nocheck((x),(ptr),sizeof(*(ptr)))#define __get_user_nocheck(x,ptr,size)					\({									\	long __gu_err = 0;						\	unsigned long __gu_val;						\	might_sleep();							\	__get_user_size(__gu_val,(ptr),(size),__gu_err);		\	(x) = (__typeof__(*(ptr)))__gu_val;				\	__gu_err;							\})#define __get_user_check(x,ptr,size)					\({									\	long __gu_err = -EFAULT;					\	unsigned long __gu_val = 0;					\	const __typeof__(*(ptr)) __user *__gu_addr = (ptr);		\	might_sleep();							\	if (access_ok(VERIFY_READ,__gu_addr,size))			\		__get_user_size(__gu_val,__gu_addr,(size),__gu_err);	\	(x) = (__typeof__(*(ptr)))__gu_val;				\	__gu_err;							\})extern long __get_user_bad(void);#define __get_user_size(x,ptr,size,retval)				\do {									\	retval = 0;							\	__chk_user_ptr(ptr);						\	switch (size) {							\	  case 1: __get_user_asm(x,ptr,retval,"ub"); break;		\	  case 2: __get_user_asm(x,ptr,retval,"uh"); break;		\	  case 4: __get_user_asm(x,ptr,retval,""); break;		\	  default: (x) = __get_user_bad();				\	}								\} while (0)#define __get_user_asm(x, addr, err, itype)				\	__asm__ __volatile__(						\		"	.fillinsn\n"					\		"1:	ld"itype" %1,@%2\n"				\		"	.fillinsn\n"					\		"2:\n"							\		".section .fixup,\"ax\"\n"				\		"	.balign 4\n"					\		"3:	ldi %0,%3\n"					\		"	seth r14,#high(2b)\n"				\		"	or3 r14,r14,#low(2b)\n"				\		"	jmp r14\n"					\		".previous\n"						\		".section __ex_table,\"a\"\n"				\		"	.balign 4\n"					\		"	.long 1b,3b\n"					\		".previous"						\		: "=&r" (err), "=&r" (x)				\
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