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root/include/asm-parisc/uaccess.h

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INCLUDED FROM


DEFINITIONS

This source file includes following definitions.
  1. access_ok

#ifndef __PARISC_UACCESS_H
#define __PARISC_UACCESS_H

/*
 * User space memory access functions
 */
#include <asm/page.h>
#include <asm/system.h>
#include <asm/cache.h>
#include <asm-generic/uaccess.h>

#define VERIFY_READ 0
#define VERIFY_WRITE 1

#define KERNEL_DS       ((mm_segment_t){0})
#define USER_DS         ((mm_segment_t){1})

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

#define get_ds()        (KERNEL_DS)
#define get_fs()        (current_thread_info()->addr_limit)
#define set_fs(x)       (current_thread_info()->addr_limit = (x))

/*
 * Note that since kernel addresses are in a separate address space on
 * parisc, we don't need to do anything for access_ok().
 * We just let the page fault handler do the right thing. This also means
 * that put_user is the same as __put_user, etc.
 */

extern int __get_kernel_bad(void);
extern int __get_user_bad(void);
extern int __put_kernel_bad(void);
extern int __put_user_bad(void);

static inline long access_ok(int type, const void __user * addr,
                unsigned long size)
{
        return 1;
}

#define put_user __put_user
#define get_user __get_user

#if !defined(CONFIG_64BIT)
#define LDD_KERNEL(ptr)         __get_kernel_bad();
#define LDD_USER(ptr)           __get_user_bad();
#define STD_KERNEL(x, ptr)      __put_kernel_asm64(x,ptr)
#define STD_USER(x, ptr)        __put_user_asm64(x,ptr)
#define ASM_WORD_INSN           ".word\t"
#else
#define LDD_KERNEL(ptr)         __get_kernel_asm("ldd",ptr)
#define LDD_USER(ptr)           __get_user_asm("ldd",ptr)
#define STD_KERNEL(x, ptr)      __put_kernel_asm("std",x,ptr)
#define STD_USER(x, ptr)        __put_user_asm("std",x,ptr)
#define ASM_WORD_INSN           ".dword\t"
#endif

/*
 * The exception table contains two values: the first is an address
 * for an instruction that is allowed to fault, and the second is
 * the address to the fixup routine. 
 */

struct exception_table_entry {
        unsigned long insn;  /* address of insn that is allowed to fault.   */
        long fixup;          /* fixup routine */
};

#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
        ".section __ex_table,\"aw\"\n"                     \
        ASM_WORD_INSN #fault_addr ", " #except_addr "\n\t" \
        ".previous\n"

/*
 * The page fault handler stores, in a per-cpu area, the following information
 * if a fixup routine is available.
 */
struct exception_data {
        unsigned long fault_ip;
        unsigned long fault_space;
        unsigned long fault_addr;
};

#define __get_user(x,ptr)                               \
({                                                      \
        register long __gu_err __asm__ ("r8") = 0;      \
        register long __gu_val __asm__ ("r9") = 0;      \
                                                        \
        if (segment_eq(get_fs(),KERNEL_DS)) {           \
            switch (sizeof(*(ptr))) {                   \
            case 1: __get_kernel_asm("ldb",ptr); break; \
            case 2: __get_kernel_asm("ldh",ptr); break; \
            case 4: __get_kernel_asm("ldw",ptr); break; \
            case 8: LDD_KERNEL(ptr); break;             \
            default: __get_kernel_bad(); break;         \
            }                                           \
        }                                               \
        else {                                          \
            switch (sizeof(*(ptr))) {                   \
            case 1: __get_user_asm("ldb",ptr); break;   \
            case 2: __get_user_asm("ldh",ptr); break;   \
            case 4: __get_user_asm("ldw",ptr); break;   \
            case 8: LDD_USER(ptr);  break;              \
            default: __get_user_bad(); break;           \
            }                                           \
        }                                               \
                                                        \
        (x) = (__typeof__(*(ptr))) __gu_val;            \
        __gu_err;                                       \
})

#define __get_kernel_asm(ldx,ptr)                       \
        __asm__("\n1:\t" ldx "\t0(%2),%0\n\t"           \
                ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
                : "=r"(__gu_val), "=r"(__gu_err)        \
                : "r"(ptr), "1"(__gu_err)               \
                : "r1");

#define __get_user_asm(ldx,ptr)                         \
        __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t"     \
                ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_get_user_skip_1)\
                : "=r"(__gu_val), "=r"(__gu_err)        \
                : "r"(ptr), "1"(__gu_err)               \
                : "r1");

#define __put_user(x,ptr)                                       \
({                                                              \
        register long __pu_err __asm__ ("r8") = 0;              \
        __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x);       \
                                                                \
        if (segment_eq(get_fs(),KERNEL_DS)) {                   \
            switch (sizeof(*(ptr))) {                           \
            case 1: __put_kernel_asm("stb",__x,ptr); break;     \
            case 2: __put_kernel_asm("sth",__x,ptr); break;     \
            case 4: __put_kernel_asm("stw",__x,ptr); break;     \
            case 8: STD_KERNEL(__x,ptr); break;                 \
            default: __put_kernel_bad(); break;                 \
            }                                                   \
        }                                                       \
        else {                                                  \
            switch (sizeof(*(ptr))) {                           \
            case 1: __put_user_asm("stb",__x,ptr); break;       \
            case 2: __put_user_asm("sth",__x,ptr); break;       \
            case 4: __put_user_asm("stw",__x,ptr); break;       \
            case 8: STD_USER(__x,ptr); break;                   \
            default: __put_user_bad(); break;                   \
            }                                                   \
        }                                                       \
                                                                \
        __pu_err;                                               \
})

/*
 * The "__put_user/kernel_asm()" macros tell gcc they read from memory
 * instead of writing. This is because they do not write to any memory
 * gcc knows about, so there are no aliasing issues. These macros must
 * also be aware that "fixup_put_user_skip_[12]" are executed in the
 * context of the fault, and any registers used there must be listed
 * as clobbers. In this case only "r1" is used by the current routines.
 * r8/r9 are already listed as err/val.
 */

#define __put_kernel_asm(stx,x,ptr)                         \
        __asm__ __volatile__ (                              \
                "\n1:\t" stx "\t%2,0(%1)\n\t"               \
                ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\
                : "=r"(__pu_err)                            \
                : "r"(ptr), "r"(x), "0"(__pu_err)           \
                : "r1")

#define __put_user_asm(stx,x,ptr)                           \
        __asm__ __volatile__ (                              \
                "\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t"         \
                ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\
                : "=r"(__pu_err)                            \
                : "r"(ptr), "r"(x), "0"(__pu_err)           \
                : "r1")


#if !defined(CONFIG_64BIT)

#define __put_kernel_asm64(__val,ptr) do {                  \
        u64 __val64 = (u64)(__val);                         \
        u32 hi = (__val64) >> 32;                           \
        u32 lo = (__val64) & 0xffffffff;                    \
        __asm__ __volatile__ (                              \
                "\n1:\tstw %2,0(%1)"                        \
                "\n2:\tstw %3,4(%1)\n\t"                    \
                ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\
                ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\
                : "=r"(__pu_err)                            \
                : "r"(ptr), "r"(hi), "r"(lo), "0"(__pu_err) \
                : "r1");                                    \
} while (0)

#define __put_user_asm64(__val,ptr) do {                    \
        u64 __val64 = (u64)(__val);                         \
        u32 hi = (__val64) >> 32;                           \
        u32 lo = (__val64) & 0xffffffff;                    \
        __asm__ __volatile__ (                              \
                "\n1:\tstw %2,0(%%sr3,%1)"                  \
                "\n2:\tstw %3,4(%%sr3,%1)\n\t"              \
                ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\
                ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\
                : "=r"(__pu_err)                            \
                : "r"(ptr), "r"(hi), "r"(lo), "0"(__pu_err) \
                : "r1");                                    \
} while (0)

#endif /* !defined(CONFIG_64BIT) */


/*
 * Complex access routines -- external declarations
 */

extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
extern long lstrncpy_from_user(char *, const char __user *, long);
extern unsigned lclear_user(void __user *,unsigned long);
extern long lstrnlen_user(const char __user *,long);

/*
 * Complex access routines -- macros
 */

#define strncpy_from_user lstrncpy_from_user
#define strnlen_user lstrnlen_user
#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
#define clear_user lclear_user
#define __clear_user lclear_user

unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len);
#define __copy_to_user copy_to_user
unsigned long copy_from_user(void *dst, const void __user *src, unsigned long len);
#define __copy_from_user copy_from_user
unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len);
#define __copy_in_user copy_in_user
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user

#endif /* __PARISC_UACCESS_H */

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