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#ifndef __i386_UACCESS_H

#define __i386_UACCESS_H

/*

 * User space memory access functions

 */

#include <linux/config.h>

#include <linux/errno.h>

#include <linux/thread_info.h>

#include <linux/prefetch.h>

#include <linux/string.h>

#include <asm/page.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) })

#define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFFUL)

#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))

#define segment_eq(a,b) ((a).seg == (b).seg)

/*

 * movsl can be slow when source and dest are not both 8-byte aligned

 */

#ifdef CONFIG_X86_INTEL_USERCOPY

extern struct movsl_mask {

        int mask;

} ____cacheline_aligned_in_smp movsl_mask;

#endif

#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,sum; \

        asm("addl %3,%1 ; sbbl %0,%0; cmpl %1,%4; sbbl $0,%0" \

                :"=&r" (flag), "=r" (sum) \

                :"1" (addr),"g" ((int)(size)),"g" (current_thread_info()->addr_limit.seg)); \

        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.

 */

#define access_ok(type,addr,size) (likely(__range_ok(addr,size) == 0))

/**

 * verify_area: - Obsolete, use access_ok()

 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE

 * @addr: User space pointer to start of block to check

 * @size: Size of block to check

 *

 * Context: User context only.  This function may sleep.

 *

 * This function has been replaced by access_ok().

 *

 * Checks if a pointer to a block of memory in user space is valid.

 *

 * Returns zero if the memory block may be valid, -EFAULT

 * if it is definitely invalid.

 *

 * See access_ok() for more details.

 */

static inline int verify_area(int type, const void __user * addr, unsigned long size)

{

        return access_ok(type,addr,size) ? 0 : -EFAULT;

}

/*

 * 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 ugliness 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).

 */

extern void __get_user_1(void);

extern void __get_user_2(void);

extern void __get_user_4(void);

#define __get_user_x(size,ret,x,ptr) \

        __asm__ __volatile__("call __get_user_" #size \

                :"=a" (ret),"=d" (x) \

                :"0" (ptr))

/* 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)                                                 \

({      int __ret_gu,__val_gu;                                          \

        switch(sizeof (*(ptr))) {                                       \

        case 1:  __get_user_x(1,__ret_gu,__val_gu,ptr); break;          \

        case 2:  __get_user_x(2,__ret_gu,__val_gu,ptr); break;          \

        case 4:  __get_user_x(4,__ret_gu,__val_gu,ptr); break;          \

        default: __get_user_x(X,__ret_gu,__val_gu,ptr); break;          \

        }                                                               \

        (x) = (__typeof__(*(ptr)))__val_gu;                             \

        __ret_gu;                                                       \

})

extern void __put_user_bad(void);

/**

 * 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)))

/**

 * __put_user: - Write a simple value into user space, with less checking.

 * @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.

 *

 * Caller must check the pointer with access_ok() before calling this

 * function.

 *

 * Returns zero on success, or -EFAULT on error.

 */

#define __put_user(x,ptr) \

  __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))

#define __put_user_nocheck(x,ptr,size)                          \

({                                                              \

        long __pu_err;                                          \

        __put_user_size((x),(ptr),(size),__pu_err,-EFAULT);     \

        __pu_err;                                               \

})

#define __put_user_check(x,ptr,size)                                    \

({                                                                      \

        long __pu_err = -EFAULT;                                        \

        __typeof__(*(ptr)) *__pu_addr = (ptr);                          \

        might_sleep();                                          \

        if (access_ok(VERIFY_WRITE,__pu_addr,size))                     \

                __put_user_size((x),__pu_addr,(size),__pu_err,-EFAULT); \

        __pu_err;                                                       \

})                                                      

#define __put_user_u64(x, addr, err)                            \

        __asm__ __volatile__(                                   \

                "1:     movl %%eax,0(%2)\n"                     \

                "2:     movl %%edx,4(%2)\n"                     \

                "3:\n"                                          \

                ".section .fixup,\"ax\"\n"                      \

                "4:     movl %3,%0\n"                           \

                "       jmp 3b\n"                               \

                ".previous\n"                                   \

                ".section __ex_table,\"a\"\n"                   \

                "       .align 4\n"                             \

                "       .long 1b,4b\n"                          \

                "       .long 2b,4b\n"                          \

                ".previous"                                     \

                : "=r"(err)                                     \

                : "A" (x), "r" (addr), "i"(-EFAULT), "0"(err))

#ifdef CONFIG_X86_WP_WORKS_OK

#define __put_user_size(x,ptr,size,retval,errret)                       \

do {                                                                    \

        retval = 0;                                                     \

        switch (size) {                                                 \

        case 1: __put_user_asm(x,ptr,retval,"b","b","iq",errret);break; \

        case 2: __put_user_asm(x,ptr,retval,"w","w","ir",errret);break; \

        case 4: __put_user_asm(x,ptr,retval,"l","","ir",errret); break; \

        case 8: __put_user_u64((__typeof__(*ptr))(x),ptr,retval); break;\

          default: __put_user_bad();                                    \

        }                                                               \

} while (0)

#else

#define __put_user_size(x,ptr,size,retval,errret)                       \

do {                                                                    \

        __typeof__(*(ptr)) __pus_tmp = x;                               \

        retval = 0;                                                     \

                                                                        \

        if(unlikely(__copy_to_user_ll(ptr, &__pus_tmp, size) != 0))     \

                retval = errret;                                        \

} while (0)

#endif

struct __large_struct { unsigned long buf[100]; };

#define __m(x) (*(struct __large_struct *)(x))

/*

 * Tell gcc we read from memory instead of writing: this is because

 * we do not write to any memory gcc knows about, so there are no

 * aliasing issues.

 */

#define __put_user_asm(x, addr, err, itype, rtype, ltype, errret)       \

        __asm__ __volatile__(                                           \

                "1:     mov"itype" %"rtype"1,%2\n"                      \

                "2:\n"                                                  \

                ".section .fixup,\"ax\"\n"                              \

                "3:     movl %3,%0\n"                                   \

                "       jmp 2b\n"                                       \

                ".previous\n"                                           \

                ".section __ex_table,\"a\"\n"                           \

                "       .align 4\n"                                     \

                "       .long 1b,3b\n"                                  \

                ".previous"                                             \

                : "=r"(err)                                             \

                : ltype (x), "m"(__m(addr)), "i"(errret), "0"(err))

#define __get_user_nocheck(x,ptr,size)                          \

({                                                              \

        long __gu_err, __gu_val;                                \

        __get_user_size(__gu_val,(ptr),(size),__gu_err,-EFAULT);\

        (x) = (__typeof__(*(ptr)))__gu_val;                     \

        __gu_err;                                               \

})

extern long __get_user_bad(void);

#define __get_user_size(x,ptr,size,retval,errret)                       \

do {                                                                    \

        retval = 0;                                                     \

        switch (size) {                                                 \

        case 1: __get_user_asm(x,ptr,retval,"b","b","=q",errret);break; \

        case 2: __get_user_asm(x,ptr,retval,"w","w","=r",errret);break; \

        case 4: __get_user_asm(x,ptr,retval,"l","","=r",errret);break;  \

        default: (x) = __get_user_bad();                                \

        }                                                               \

} while (0)

#define __get_user_asm(x, addr, err, itype, rtype, ltype, errret)       \

        __asm__ __volatile__(                                           \

                "1:     mov"itype" %2,%"rtype"1\n"                      \

                "2:\n"                                                  \

                ".section .fixup,\"ax\"\n"                              \

                "3:     movl %3,%0\n"                                   \

                "       xor"itype" %"rtype"1,%"rtype"1\n"               \

                "       jmp 2b\n"                                       \

                ".previous\n"                                           \

                ".section __ex_table,\"a\"\n"                           \

                "       .align 4\n"                                     \

                "       .long 1b,3b\n"                                  \

                ".previous"                                             \

                : "=r"(err), ltype (x)                                  \

                : "m"(__m(addr)), "i"(errret), "0"(err))

static inline unsigned long __copy_to_user_ll(void __user *to, const void *from, unsigned long n) {

  memcpy(to,from,n);

  return 0;

}

static inline unsigned long __copy_from_user_ll(void *to, const void __user *from, unsigned long n) {

  memcpy(to,from,n);

  return 0;

}

/*

 * Here we special-case 1, 2 and 4-byte copy_*_user invocations.  On a fault

 * we return the initial request size (1, 2 or 4), as copy_*_user should do.

 * If a store crosses a page boundary and gets a fault, the x86 will not write

 * anything, so this is accurate.

 */

/**

 * __copy_to_user: - Copy a block of data into user space, with less checking.

 * @to:   Destination address, in user space.

 * @from: Source address, in kernel space.

 * @n:    Number of bytes to copy.

 *

 * Context: User context only.  This function may sleep.

 *

 * Copy data from kernel space to user space.  Caller must check

 * the specified block with access_ok() before calling this function.

 *

 * Returns number of bytes that could not be copied.

 * On success, this will be zero.

 */

static inline unsigned long

__copy_to_user(void __user *to, const void *from, unsigned long n)

{

        memcpy(to,from,n);

        return 0;

}

/**

 * __copy_from_user: - Copy a block of data from user space, with less checking.

 * @to:   Destination address, in kernel space.

 * @from: Source address, in user space.

 * @n:    Number of bytes to copy.

 *

 * Context: User context only.  This function may sleep.

 *

 * Copy data from user space to kernel space.  Caller must check

 * the specified block with access_ok() before calling this function.

 *

 * Returns number of bytes that could not be copied.

 * On success, this will be zero.

 *

 * If some data could not be copied, this function will pad the copied

 * data to the requested size using zero bytes.

 */

static inline unsigned long

__copy_from_user(void *to, const void __user *from, unsigned long n)

{

        if (__builtin_constant_p(n)) {

                unsigned long ret;

                switch (n) {

                case 1:

                        __get_user_size(*(u8 *)to, from, 1, ret, 1);

                        return ret;

                case 2:

                        __get_user_size(*(u16 *)to, from, 2, ret, 2);

                        return ret;

                case 4:

                        __get_user_size(*(u32 *)to, from, 4, ret, 4);

                        return ret;

                }

        }

        return __copy_from_user_ll(to, from, n);

}

/**

 * copy_to_user: - Copy a block of data into user space.

 * @to:   Destination address, in user space.

 * @from: Source address, in kernel space.

 * @n:    Number of bytes to copy.

 *

 * Context: User context only.  This function may sleep.

 *

 * Copy data from kernel space to user space.

 *

 * Returns number of bytes that could not be copied.

 * On success, this will be zero.

 */

static inline unsigned long

copy_to_user(void __user *to, const void *from, unsigned long n)

{

        memcpy(to, from, n);

        return 0;

}

/**

 * copy_from_user: - Copy a block of data from user space.

 * @to:   Destination address, in kernel space.

 * @from: Source address, in user space.

 * @n:    Number of bytes to copy.

 *

 * Context: User context only.  This function may sleep.

 *

 * Copy data from user space to kernel space.

 *

 * Returns number of bytes that could not be copied.

 * On success, this will be zero.

 *

 * If some data could not be copied, this function will pad the copied

 * data to the requested size using zero bytes.

 */

static inline unsigned long

copy_from_user(void *to, const void __user *from, unsigned long n)

{

        memcpy(to, from, n);

        return 0;

}

long strncpy_from_user(char *dst, const char __user *src, long count);

long __strncpy_from_user(char *dst, const char __user *src, long count);

/**

 * strlen_user: - Get the size of a string in user space.

 * @str: The string to measure.

 *

 * Context: User context only.  This function may sleep.

 *

 * Get the size of a NUL-terminated string in user space.

 *

 * Returns the size of the string INCLUDING the terminating NUL.

 * On exception, returns 0.

 *

 * If there is a limit on the length of a valid string, you may wish to

 * consider using strnlen_user() instead.

 */

#define strlen_user(str) strnlen_user(str, ~0UL >> 1)

long strnlen_user(const char __user *str, long n);

unsigned long clear_user(void __user *mem, unsigned long len);

unsigned long __clear_user(void __user *mem, unsigned long len);

#endif /* __i386_UACCESS_H */