paccess.h

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/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1996, 1997, 1998, 1999, 2000 by Ralf Baechle
 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
 *
 * Protected memory access.  Used for everything that might take revenge
 * by sending a DBE error like accessing possibly non-existent memory or
 * devices.
 */
#ifndef _ASM_PACCESS_H
#define _ASM_PACCESS_H

#include <linux/errno.h>

#ifdef CONFIG_32BIT
#define __PA_ADDR   ".word"
#endif
#ifdef CONFIG_64BIT
#define __PA_ADDR   ".dword"
#endif

extern asmlinkage void handle_ibe(void);
extern asmlinkage void handle_dbe(void);

#define put_dbe(x, ptr) __put_dbe((x), (ptr), sizeof(*(ptr)))
#define get_dbe(x, ptr) __get_dbe((x), (ptr), sizeof(*(ptr)))

struct __large_pstruct { unsigned long buf[100]; };
#define __mp(x) (*(struct __large_pstruct *)(x))

#define __get_dbe(x, ptr, size)                     \
({                                  \
    long __gu_err;                          \
    __typeof__(*(ptr)) __gu_val;                    \
    unsigned long __gu_addr;                    \
    __asm__("":"=r" (__gu_val));                    \
    __gu_addr = (unsigned long) (ptr);              \
    __asm__("":"=r" (__gu_err));                    \
    switch (size) {                         \
    case 1: __get_dbe_asm("lb"); break;             \
    case 2: __get_dbe_asm("lh"); break;             \
    case 4: __get_dbe_asm("lw"); break;             \
    case 8:  __get_dbe_asm("ld"); break;                \
    default: __get_dbe_unknown(); break;                \
    }                               \
    x = (__typeof__(*(ptr))) __gu_val;              \
    __gu_err;                           \
})

#define __get_dbe_asm(insn)                     \
{                                   \
    __asm__ __volatile__(                       \
    "1:\t" insn "\t%1,%2\n\t"                   \
    "move\t%0,$0\n"                         \
    "2:\n\t"                            \
    ".section\t.fixup,\"ax\"\n"                 \
    "3:\tli\t%0,%3\n\t"                     \
    "move\t%1,$0\n\t"                       \
    "j\t2b\n\t"                         \
    ".previous\n\t"                         \
    ".section\t__dbe_table,\"a\"\n\t"               \
    __PA_ADDR "\t1b, 3b\n\t"                    \
    ".previous"                         \
    :"=r" (__gu_err), "=r" (__gu_val)               \
    :"o" (__mp(__gu_addr)), "i" (-EFAULT));             \
}

extern void __get_dbe_unknown(void);

#define __put_dbe(x, ptr, size)                     \
({                                  \
    long __pu_err;                          \
    __typeof__(*(ptr)) __pu_val;                    \
    long __pu_addr;                         \
    __pu_val = (x);                         \
    __pu_addr = (long) (ptr);                   \
    __asm__("":"=r" (__pu_err));                    \
    switch (size) {                         \
    case 1: __put_dbe_asm("sb"); break;             \
    case 2: __put_dbe_asm("sh"); break;             \
    case 4: __put_dbe_asm("sw"); break;             \
    case 8: __put_dbe_asm("sd"); break;             \
    default: __put_dbe_unknown(); break;                \
    }                               \
    __pu_err;                           \
})

#define __put_dbe_asm(insn)                     \
{                                   \
    __asm__ __volatile__(                       \
    "1:\t" insn "\t%1,%2\n\t"                   \
    "move\t%0,$0\n"                         \
    "2:\n\t"                            \
    ".section\t.fixup,\"ax\"\n"                 \
    "3:\tli\t%0,%3\n\t"                     \
    "j\t2b\n\t"                         \
    ".previous\n\t"                         \
    ".section\t__dbe_table,\"a\"\n\t"               \
    __PA_ADDR "\t1b, 3b\n\t"                    \
    ".previous"                         \
    : "=r" (__pu_err)                       \
    : "r" (__pu_val), "o" (__mp(__pu_addr)), "i" (-EFAULT));    \
}

extern void __put_dbe_unknown(void);

extern unsigned long search_dbe_table(unsigned long addr);

#endif /* _ASM_PACCESS_H */