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root/include/asm-m68k/uaccess.h

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INCLUDED FROM


DEFINITIONS

This source file includes following definitions.
  1. access_ok
  2. __constant_copy_from_user
  3. __constant_copy_to_user

#ifndef __M68K_UACCESS_H
#define __M68K_UACCESS_H

/*
 * User space memory access functions
 */
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <asm/segment.h>

#define VERIFY_READ     0
#define VERIFY_WRITE    1

/* We let the MMU do all checking */
static inline int access_ok(int type, const void __user *addr,
                            unsigned long size)
{
        return 1;
}

/*
 * 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 __put_user_bad(void);
extern int __get_user_bad(void);

#define __put_user_asm(res, x, ptr, bwl, reg, err)      \
asm volatile ("\n"                                      \
        "1:     moves."#bwl"    %2,%1\n"                \
        "2:\n"                                          \
        "       .section .fixup,\"ax\"\n"               \
        "       .even\n"                                \
        "10:    moveq.l %3,%0\n"                        \
        "       jra 2b\n"                               \
        "       .previous\n"                            \
        "\n"                                            \
        "       .section __ex_table,\"a\"\n"            \
        "       .align  4\n"                            \
        "       .long   1b,10b\n"                       \
        "       .long   2b,10b\n"                       \
        "       .previous"                              \
        : "+d" (res), "=m" (*(ptr))                     \
        : #reg (x), "i" (err))

/*
 * These are the main single-value transfer routines.  They automatically
 * use the right size if we just have the right pointer type.
 */

#define __put_user(x, ptr)                                              \
({                                                                      \
        typeof(*(ptr)) __pu_val = (x);                                  \
        int __pu_err = 0;                                               \
        __chk_user_ptr(ptr);                                            \
        switch (sizeof (*(ptr))) {                                      \
        case 1:                                                         \
                __put_user_asm(__pu_err, __pu_val, ptr, b, d, -EFAULT); \
                break;                                                  \
        case 2:                                                         \
                __put_user_asm(__pu_err, __pu_val, ptr, w, d, -EFAULT); \
                break;                                                  \
        case 4:                                                         \
                __put_user_asm(__pu_err, __pu_val, ptr, l, r, -EFAULT); \
                break;                                                  \
        case 8:                                                         \
            {                                                           \
                const void __user *__pu_ptr = (ptr);                    \
                asm volatile ("\n"                                      \
                        "1:     moves.l %2,(%1)+\n"                     \
                        "2:     moves.l %R2,(%1)\n"                     \
                        "3:\n"                                          \
                        "       .section .fixup,\"ax\"\n"               \
                        "       .even\n"                                \
                        "10:    movel %3,%0\n"                          \
                        "       jra 3b\n"                               \
                        "       .previous\n"                            \
                        "\n"                                            \
                        "       .section __ex_table,\"a\"\n"            \
                        "       .align 4\n"                             \
                        "       .long 1b,10b\n"                         \
                        "       .long 2b,10b\n"                         \
                        "       .long 3b,10b\n"                         \
                        "       .previous"                              \
                        : "+d" (__pu_err), "+a" (__pu_ptr)              \
                        : "r" (__pu_val), "i" (-EFAULT)                 \
                        : "memory");                                    \
                break;                                                  \
            }                                                           \
        default:                                                        \
                __pu_err = __put_user_bad();                            \
                break;                                                  \
        }                                                               \
        __pu_err;                                                       \
})
#define put_user(x, ptr)        __put_user(x, ptr)


#define __get_user_asm(res, x, ptr, type, bwl, reg, err) ({     \
        type __gu_val;                                          \
        asm volatile ("\n"                                      \
                "1:     moves."#bwl"    %2,%1\n"                \
                "2:\n"                                          \
                "       .section .fixup,\"ax\"\n"               \
                "       .even\n"                                \
                "10:    move.l  %3,%0\n"                        \
                "       sub."#bwl"      %1,%1\n"                \
                "       jra     2b\n"                           \
                "       .previous\n"                            \
                "\n"                                            \
                "       .section __ex_table,\"a\"\n"            \
                "       .align  4\n"                            \
                "       .long   1b,10b\n"                       \
                "       .previous"                              \
                : "+d" (res), "=&" #reg (__gu_val)              \
                : "m" (*(ptr)), "i" (err));                     \
        (x) = (typeof(*(ptr)))(unsigned long)__gu_val;          \
})

#define __get_user(x, ptr)                                              \
({                                                                      \
        int __gu_err = 0;                                               \
        __chk_user_ptr(ptr);                                            \
        switch (sizeof(*(ptr))) {                                       \
        case 1:                                                         \
                __get_user_asm(__gu_err, x, ptr, u8, b, d, -EFAULT);    \
                break;                                                  \
        case 2:                                                         \
                __get_user_asm(__gu_err, x, ptr, u16, w, d, -EFAULT);   \
                break;                                                  \
        case 4:                                                         \
                __get_user_asm(__gu_err, x, ptr, u32, l, r, -EFAULT);   \
                break;                                                  \
/*      case 8: disabled because gcc-4.1 has a broken typeof            \
            {                                                           \
                const void *__gu_ptr = (ptr);                           \
                u64 __gu_val;                                           \
                asm volatile ("\n"                                      \
                        "1:     moves.l (%2)+,%1\n"                     \
                        "2:     moves.l (%2),%R1\n"                     \
                        "3:\n"                                          \
                        "       .section .fixup,\"ax\"\n"               \
                        "       .even\n"                                \
                        "10:    move.l  %3,%0\n"                        \
                        "       sub.l   %1,%1\n"                        \
                        "       sub.l   %R1,%R1\n"                      \
                        "       jra     3b\n"                           \
                        "       .previous\n"                            \
                        "\n"                                            \
                        "       .section __ex_table,\"a\"\n"            \
                        "       .align  4\n"                            \
                        "       .long   1b,10b\n"                       \
                        "       .long   2b,10b\n"                       \
                        "       .previous"                              \
                        : "+d" (__gu_err), "=&r" (__gu_val),            \
                          "+a" (__gu_ptr)                               \
                        : "i" (-EFAULT)                                 \
                        : "memory");                                    \
                (x) = (typeof(*(ptr)))__gu_val;                         \
                break;                                                  \
            }   */                                                      \
        default:                                                        \
                __gu_err = __get_user_bad();                            \
                break;                                                  \
        }                                                               \
        __gu_err;                                                       \
})
#define get_user(x, ptr) __get_user(x, ptr)

unsigned long __generic_copy_from_user(void *to, const void __user *from, unsigned long n);
unsigned long __generic_copy_to_user(void __user *to, const void *from, unsigned long n);

#define __constant_copy_from_user_asm(res, to, from, tmp, n, s1, s2, s3)\
        asm volatile ("\n"                                              \
                "1:     moves."#s1"     (%2)+,%3\n"                     \
                "       move."#s1"      %3,(%1)+\n"                     \
                "2:     moves."#s2"     (%2)+,%3\n"                     \
                "       move."#s2"      %3,(%1)+\n"                     \
                "       .ifnc   \""#s3"\",\"\"\n"                       \
                "3:     moves."#s3"     (%2)+,%3\n"                     \
                "       move."#s3"      %3,(%1)+\n"                     \
                "       .endif\n"                                       \
                "4:\n"                                                  \
                "       .section __ex_table,\"a\"\n"                    \
                "       .align  4\n"                                    \
                "       .long   1b,10f\n"                               \
                "       .long   2b,20f\n"                               \
                "       .ifnc   \""#s3"\",\"\"\n"                       \
                "       .long   3b,30f\n"                               \
                "       .endif\n"                                       \
                "       .previous\n"                                    \
                "\n"                                                    \
                "       .section .fixup,\"ax\"\n"                       \
                "       .even\n"                                        \
                "10:    clr."#s1"       (%1)+\n"                        \
                "20:    clr."#s2"       (%1)+\n"                        \
                "       .ifnc   \""#s3"\",\"\"\n"                       \
                "30:    clr."#s3"       (%1)+\n"                        \
                "       .endif\n"                                       \
                "       moveq.l #"#n",%0\n"                             \
                "       jra     4b\n"                                   \
                "       .previous\n"                                    \
                : "+d" (res), "+&a" (to), "+a" (from), "=&d" (tmp)      \
                : : "memory")

static __always_inline unsigned long
__constant_copy_from_user(void *to, const void __user *from, unsigned long n)
{
        unsigned long res = 0, tmp;

        switch (n) {
        case 1:
                __get_user_asm(res, *(u8 *)to, (u8 __user *)from, u8, b, d, 1);
                break;
        case 2:
                __get_user_asm(res, *(u16 *)to, (u16 __user *)from, u16, w, d, 2);
                break;
        case 3:
                __constant_copy_from_user_asm(res, to, from, tmp, 3, w, b,);
                break;
        case 4:
                __get_user_asm(res, *(u32 *)to, (u32 __user *)from, u32, l, r, 4);
                break;
        case 5:
                __constant_copy_from_user_asm(res, to, from, tmp, 5, l, b,);
                break;
        case 6:
                __constant_copy_from_user_asm(res, to, from, tmp, 6, l, w,);
                break;
        case 7:
                __constant_copy_from_user_asm(res, to, from, tmp, 7, l, w, b);
                break;
        case 8:
                __constant_copy_from_user_asm(res, to, from, tmp, 8, l, l,);
                break;
        case 9:
                __constant_copy_from_user_asm(res, to, from, tmp, 9, l, l, b);
                break;
        case 10:
                __constant_copy_from_user_asm(res, to, from, tmp, 10, l, l, w);
                break;
        case 12:
                __constant_copy_from_user_asm(res, to, from, tmp, 12, l, l, l);
                break;
        default:
                /* we limit the inlined version to 3 moves */
                return __generic_copy_from_user(to, from, n);
        }

        return res;
}

#define __constant_copy_to_user_asm(res, to, from, tmp, n, s1, s2, s3)  \
        asm volatile ("\n"                                              \
                "       move."#s1"      (%2)+,%3\n"                     \
                "11:    moves."#s1"     %3,(%1)+\n"                     \
                "12:    move."#s2"      (%2)+,%3\n"                     \
                "21:    moves."#s2"     %3,(%1)+\n"                     \
                "22:\n"                                                 \
                "       .ifnc   \""#s3"\",\"\"\n"                       \
                "       move."#s3"      (%2)+,%3\n"                     \
                "31:    moves."#s3"     %3,(%1)+\n"                     \
                "32:\n"                                                 \
                "       .endif\n"                                       \
                "4:\n"                                                  \
                "\n"                                                    \
                "       .section __ex_table,\"a\"\n"                    \
                "       .align  4\n"                                    \
                "       .long   11b,5f\n"                               \
                "       .long   12b,5f\n"                               \
                "       .long   21b,5f\n"                               \
                "       .long   22b,5f\n"                               \
                "       .ifnc   \""#s3"\",\"\"\n"                       \
                "       .long   31b,5f\n"                               \
                "       .long   32b,5f\n"                               \
                "       .endif\n"                                       \
                "       .previous\n"                                    \
                "\n"                                                    \
                "       .section .fixup,\"ax\"\n"                       \
                "       .even\n"                                        \
                "5:     moveq.l #"#n",%0\n"                             \
                "       jra     4b\n"                                   \
                "       .previous\n"                                    \
                : "+d" (res), "+a" (to), "+a" (from), "=&d" (tmp)       \
                : : "memory")

static __always_inline unsigned long
__constant_copy_to_user(void __user *to, const void *from, unsigned long n)
{
        unsigned long res = 0, tmp;

        switch (n) {
        case 1:
                __put_user_asm(res, *(u8 *)from, (u8 __user *)to, b, d, 1);
                break;
        case 2:
                __put_user_asm(res, *(u16 *)from, (u16 __user *)to, w, d, 2);
                break;
        case 3:
                __constant_copy_to_user_asm(res, to, from, tmp, 3, w, b,);
                break;
        case 4:
                __put_user_asm(res, *(u32 *)from, (u32 __user *)to, l, r, 4);
                break;
        case 5:
                __constant_copy_to_user_asm(res, to, from, tmp, 5, l, b,);
                break;
        case 6:
                __constant_copy_to_user_asm(res, to, from, tmp, 6, l, w,);
                break;
        case 7:
                __constant_copy_to_user_asm(res, to, from, tmp, 7, l, w, b);
                break;
        case 8:
                __constant_copy_to_user_asm(res, to, from, tmp, 8, l, l,);
                break;
        case 9:
                __constant_copy_to_user_asm(res, to, from, tmp, 9, l, l, b);
                break;
        case 10:
                __constant_copy_to_user_asm(res, to, from, tmp, 10, l, l, w);
                break;
        case 12:
                __constant_copy_to_user_asm(res, to, from, tmp, 12, l, l, l);
                break;
        default:
                /* limit the inlined version to 3 moves */
                return __generic_copy_to_user(to, from, n);
        }

        return res;
}

#define __copy_from_user(to, from, n)           \
(__builtin_constant_p(n) ?                      \
 __constant_copy_from_user(to, from, n) :       \
 __generic_copy_from_user(to, from, n))

#define __copy_to_user(to, from, n)             \
(__builtin_constant_p(n) ?                      \
 __constant_copy_to_user(to, from, n) :         \
 __generic_copy_to_user(to, from, n))

#define __copy_to_user_inatomic         __copy_to_user
#define __copy_from_user_inatomic       __copy_from_user

#define copy_from_user(to, from, n)     __copy_from_user(to, from, n)
#define copy_to_user(to, from, n)       __copy_to_user(to, from, n)

long strncpy_from_user(char *dst, const char __user *src, long count);
long strnlen_user(const char __user *src, long n);
unsigned long __clear_user(void __user *to, unsigned long n);

#define clear_user      __clear_user

#define strlen_user(str) strnlen_user(str, 32767)

#endif /* _M68K_UACCESS_H */

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