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/* $Id: uaccess.h,v 1.1.1.1 2004-04-15 02:40:30 phoenix Exp $

 * uaccess.h: User space memore access functions.

 *

 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)

 * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)

 */

#ifndef _ASM_UACCESS_H

#define _ASM_UACCESS_H

#ifdef __KERNEL__

#include <linux/sched.h>

#include <linux/string.h>

#include <asm/vac-ops.h>

#include <asm/a.out.h>

#endif

#ifndef __ASSEMBLY__

/* Sparc is not segmented, however we need to be able to fool verify_area()

 * when doing system calls from kernel mode legitimately.

 *

 * "For historical reasons, these macros are grossly misnamed." -Linus

 */

#define KERNEL_DS   ((mm_segment_t) { 0 })

#define USER_DS     ((mm_segment_t) { -1 })

#define VERIFY_READ     0

#define VERIFY_WRITE    1

#define get_ds()        (KERNEL_DS)

#define get_fs()        (current->thread.current_ds)

#define set_fs(val)     ((current->thread.current_ds) = (val))

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

/* We have there a nice not-mapped page at PAGE_OFFSET - PAGE_SIZE, so that this test

 * can be fairly lightweight.

 * No one can read/write anything from userland in the kernel space by setting

 * large size and address near to PAGE_OFFSET - a fault will break his intentions.

 */

#define __user_ok(addr,size) ((addr) < STACK_TOP)

#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))

#define __access_ok(addr,size) (__user_ok((addr) & get_fs().seg,(size)))

#define access_ok(type,addr,size) __access_ok((unsigned long)(addr),(size))

extern inline int verify_area(int type, const void * 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.

 *

 * There is a special way how to put a range of potentially faulting

 * insns (like twenty ldd/std's with now intervening other instructions)

 * You specify address of first in insn and 0 in fixup and in the next

 * exception_table_entry you specify last potentially faulting insn + 1

 * and in fixup the routine which should handle the fault.

 * That fixup code will get

 * (faulting_insn_address - first_insn_in_the_range_address)/4

 * in %g2 (ie. index of the faulting instruction in the range).

 */

struct exception_table_entry

{

        unsigned long insn, fixup;

};

/* Returns 0 if exception not found and fixup otherwise.  */

extern unsigned long search_exception_table(unsigned long, unsigned long *);

extern void __ret_efault(void);

/* Uh, these should become 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.

 */

#define put_user(x,ptr) ({ \

unsigned long __pu_addr = (unsigned long)(ptr); \

__put_user_check((__typeof__(*(ptr)))(x),__pu_addr,sizeof(*(ptr))); })

#define get_user(x,ptr) ({ \

unsigned long __gu_addr = (unsigned long)(ptr); \

__get_user_check((x),__gu_addr,sizeof(*(ptr)),__typeof__(*(ptr))); })

/*

 * The "__xxx" versions do not do address space checking, useful when

 * doing multiple accesses to the same area (the user has to do the

 * checks by hand with "access_ok()")

 */

#define __put_user(x,ptr) __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))

#define __get_user(x,ptr) __get_user_nocheck((x),(ptr),sizeof(*(ptr)),__typeof__(*(ptr)))

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

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

#define __put_user_check(x,addr,size) ({ \

register int __pu_ret; \

if (__access_ok(addr,size)) { \

switch (size) { \

case 1: __put_user_asm(x,b,addr,__pu_ret); break; \

case 2: __put_user_asm(x,h,addr,__pu_ret); break; \

case 4: __put_user_asm(x,,addr,__pu_ret); break; \

case 8: __put_user_asm(x,d,addr,__pu_ret); break; \

default: __pu_ret = __put_user_bad(); break; \

} } else { __pu_ret = -EFAULT; } __pu_ret; })

#define __put_user_check_ret(x,addr,size,retval) ({ \

register int __foo __asm__ ("l1"); \

if (__access_ok(addr,size)) { \

switch (size) { \

case 1: __put_user_asm_ret(x,b,addr,retval,__foo); break; \

case 2: __put_user_asm_ret(x,h,addr,retval,__foo); break; \

case 4: __put_user_asm_ret(x,,addr,retval,__foo); break; \

case 8: __put_user_asm_ret(x,d,addr,retval,__foo); break; \

default: if (__put_user_bad()) return retval; break; \

} } else return retval; })

#define __put_user_nocheck(x,addr,size) ({ \

register int __pu_ret; \

switch (size) { \

case 1: __put_user_asm(x,b,addr,__pu_ret); break; \

case 2: __put_user_asm(x,h,addr,__pu_ret); break; \

case 4: __put_user_asm(x,,addr,__pu_ret); break; \

case 8: __put_user_asm(x,d,addr,__pu_ret); break; \

default: __pu_ret = __put_user_bad(); break; \

} __pu_ret; })

#define __put_user_nocheck_ret(x,addr,size,retval) ({ \

register int __foo __asm__ ("l1"); \

switch (size) { \

case 1: __put_user_asm_ret(x,b,addr,retval,__foo); break; \

case 2: __put_user_asm_ret(x,h,addr,retval,__foo); break; \

case 4: __put_user_asm_ret(x,,addr,retval,__foo); break; \

case 8: __put_user_asm_ret(x,d,addr,retval,__foo); break; \

default: if (__put_user_bad()) return retval; break; \

} })

#define __put_user_asm(x,size,addr,ret)                                 \

__asm__ __volatile__(                                                   \

        "/* Put user asm, inline. */\n"                                 \

"1:\t"  "st"#size " %1, %2\n\t"                                         \

        "clr    %0\n"                                                   \

"2:\n\n\t"                                                              \

        ".section .fixup,#alloc,#execinstr\n\t"                         \

        ".align 4\n"                                                    \

"3:\n\t"                                                                \

        "b      2b\n\t"                                                 \

        " mov   %3, %0\n\t"                                             \

        ".previous\n\n\t"                                               \

        ".section __ex_table,#alloc\n\t"                                \

        ".align 4\n\t"                                                  \

        ".word  1b, 3b\n\t"                                             \

        ".previous\n\n\t"                                               \

       : "=&r" (ret) : "r" (x), "m" (*__m(addr)),                       \

         "i" (-EFAULT))

#define __put_user_asm_ret(x,size,addr,ret,foo)                         \

if (__builtin_constant_p(ret) && ret == -EFAULT)                        \

__asm__ __volatile__(                                                   \

        "/* Put user asm ret, inline. */\n"                             \

"1:\t"  "st"#size " %1, %2\n\n\t"                                       \

        ".section __ex_table,#alloc\n\t"                                \

        ".align 4\n\t"                                                  \

        ".word  1b, __ret_efault\n\n\t"                                 \

        ".previous\n\n\t"                                               \

       : "=r" (foo) : "r" (x), "m" (*__m(addr)));                       \

else                                                                    \

__asm__ __volatile(                                                     \

        "/* Put user asm ret, inline. */\n"                             \

"1:\t"  "st"#size " %1, %2\n\n\t"                                       \

        ".section .fixup,#alloc,#execinstr\n\t"                         \

        ".align 4\n"                                                    \

"3:\n\t"                                                                \

        "ret\n\t"                                                       \

        " restore %%g0, %3, %%o0\n\t"                                   \

        ".previous\n\n\t"                                               \

        ".section __ex_table,#alloc\n\t"                                \

        ".align 4\n\t"                                                  \

        ".word  1b, 3b\n\n\t"                                           \

        ".previous\n\n\t"                                               \

       : "=r" (foo) : "r" (x), "m" (*__m(addr)), "i" (ret))

extern int __put_user_bad(void);

#define __get_user_check(x,addr,size,type) ({ \

register int __gu_ret; \

register unsigned long __gu_val; \

if (__access_ok(addr,size)) { \

switch (size) { \

case 1: __get_user_asm(__gu_val,ub,addr,__gu_ret); break; \

case 2: __get_user_asm(__gu_val,uh,addr,__gu_ret); break; \

case 4: __get_user_asm(__gu_val,,addr,__gu_ret); break; \

case 8: __get_user_asm(__gu_val,d,addr,__gu_ret); break; \

default: __gu_val = 0; __gu_ret = __get_user_bad(); break; \

} } else { __gu_val = 0; __gu_ret = -EFAULT; } x = (type) __gu_val; __gu_ret; })

#define __get_user_check_ret(x,addr,size,type,retval) ({ \

register unsigned long __gu_val __asm__ ("l1"); \

if (__access_ok(addr,size)) { \

switch (size) { \

case 1: __get_user_asm_ret(__gu_val,ub,addr,retval); break; \

case 2: __get_user_asm_ret(__gu_val,uh,addr,retval); break; \

case 4: __get_user_asm_ret(__gu_val,,addr,retval); break; \

case 8: __get_user_asm_ret(__gu_val,d,addr,retval); break; \

default: if (__get_user_bad()) return retval; \

} x = (type) __gu_val; } else return retval; })

#define __get_user_nocheck(x,addr,size,type) ({ \

register int __gu_ret; \

register unsigned long __gu_val; \

switch (size) { \

case 1: __get_user_asm(__gu_val,ub,addr,__gu_ret); break; \

case 2: __get_user_asm(__gu_val,uh,addr,__gu_ret); break; \

case 4: __get_user_asm(__gu_val,,addr,__gu_ret); break; \

case 8: __get_user_asm(__gu_val,d,addr,__gu_ret); break; \

default: __gu_val = 0; __gu_ret = __get_user_bad(); break; \

} x = (type) __gu_val; __gu_ret; })

#define __get_user_nocheck_ret(x,addr,size,type,retval) ({ \

register unsigned long __gu_val __asm__ ("l1"); \

switch (size) { \

case 1: __get_user_asm_ret(__gu_val,ub,addr,retval); break; \

case 2: __get_user_asm_ret(__gu_val,uh,addr,retval); break; \

case 4: __get_user_asm_ret(__gu_val,,addr,retval); break; \

case 8: __get_user_asm_ret(__gu_val,d,addr,retval); break; \

default: if (__get_user_bad()) return retval; \

} x = (type) __gu_val; })

#define __get_user_asm(x,size,addr,ret)                                 \

__asm__ __volatile__(                                                   \

        "/* Get user asm, inline. */\n"                                 \

"1:\t"  "ld"#size " %2, %1\n\t"                                         \

        "clr    %0\n"                                                   \

"2:\n\n\t"                                                              \

        ".section .fixup,#alloc,#execinstr\n\t"                         \

        ".align 4\n"                                                    \

"3:\n\t"                                                                \

        "clr    %1\n\t"                                                 \

        "b      2b\n\t"                                                 \

        " mov   %3, %0\n\n\t"                                           \

        ".previous\n\t"                                                 \

        ".section __ex_table,#alloc\n\t"                                \

        ".align 4\n\t"                                                  \

        ".word  1b, 3b\n\n\t"                                           \

        ".previous\n\t"                                                 \

       : "=&r" (ret), "=&r" (x) : "m" (*__m(addr)),                     \

         "i" (-EFAULT))

#define __get_user_asm_ret(x,size,addr,retval)                          \

if (__builtin_constant_p(retval) && retval == -EFAULT)                  \

__asm__ __volatile__(                                                   \

        "/* Get user asm ret, inline. */\n"                             \

"1:\t"  "ld"#size " %1, %0\n\n\t"                                       \

        ".section __ex_table,#alloc\n\t"                                \

        ".align 4\n\t"                                                  \

        ".word  1b,__ret_efault\n\n\t"                                  \

        ".previous\n\t"                                                 \

       : "=&r" (x) : "m" (*__m(addr)));                                 \

else                                                                    \

__asm__ __volatile__(                                                   \

        "/* Get user asm ret, inline. */\n"                             \

"1:\t"  "ld"#size " %1, %0\n\n\t"                                       \

        ".section .fixup,#alloc,#execinstr\n\t"                         \

        ".align 4\n"                                                    \

"3:\n\t"                                                                \

        "ret\n\t"                                                       \

        " restore %%g0, %2, %%o0\n\n\t"                                 \

        ".previous\n\t"                                                 \

        ".section __ex_table,#alloc\n\t"                                \

        ".align 4\n\t"                                                  \

        ".word  1b, 3b\n\n\t"                                           \

        ".previous\n\t"                                                 \

       : "=&r" (x) : "m" (*__m(addr)), "i" (retval))

extern int __get_user_bad(void);

extern __kernel_size_t __copy_user(void *to, void *from, __kernel_size_t size);

#define copy_to_user(to,from,n) ({ \

void *__copy_to = (void *) (to); \

__kernel_size_t __copy_size = (__kernel_size_t) (n); \

__kernel_size_t __copy_res; \

if(__copy_size && __access_ok((unsigned long)__copy_to, __copy_size)) { \

__copy_res = __copy_user(__copy_to, (void *) (from), __copy_size); \

} else __copy_res = __copy_size; \

__copy_res; })

#define __copy_to_user(to,from,n)               \

        __copy_user((void *)(to),               \

                    (void *)(from), n)

#define copy_from_user(to,from,n) ({ \

void *__copy_to = (void *) (to); \

void *__copy_from = (void *) (from); \

__kernel_size_t __copy_size = (__kernel_size_t) (n); \

__kernel_size_t __copy_res; \

if(__copy_size && __access_ok((unsigned long)__copy_from, __copy_size)) { \

__copy_res = __copy_user(__copy_to, __copy_from, __copy_size); \

} else __copy_res = __copy_size; \

__copy_res; })

#define __copy_from_user(to,from,n)             \

        __copy_user((void *)(to),               \

                    (void *)(from), n)

extern __inline__ __kernel_size_t __clear_user(void *addr, __kernel_size_t size)

{

  __kernel_size_t ret;

  __asm__ __volatile__ (

        ".section __ex_table,#alloc\n\t"

        ".align 4\n\t"

        ".word 1f,3\n\t"

        ".previous\n\t"

        "mov %2, %%o1\n"

        "1:\n\t"

        "call __bzero\n\t"

        " mov %1, %%o0\n\t"

        "mov %%o0, %0\n"

        : "=r" (ret) : "r" (addr), "r" (size) :

        "o0", "o1", "o2", "o3", "o4", "o5", "o7",

        "g1", "g2", "g3", "g4", "g5", "g7", "cc");

  return ret;

}

#define clear_user(addr,n) ({ \

void *__clear_addr = (void *) (addr); \

__kernel_size_t __clear_size = (__kernel_size_t) (n); \

__kernel_size_t __clear_res; \

if(__clear_size && __access_ok((unsigned long)__clear_addr, __clear_size)) { \

__clear_res = __clear_user(__clear_addr, __clear_size); \

} else __clear_res = __clear_size; \

__clear_res; })

extern int __strncpy_from_user(unsigned long dest, unsigned long src, int count);

#define strncpy_from_user(dest,src,count) ({ \

unsigned long __sfu_src = (unsigned long) (src); \

int __sfu_count = (int) (count); \

long __sfu_res = -EFAULT; \

if(__access_ok(__sfu_src, __sfu_count)) { \

__sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \

} __sfu_res; })

extern int __strlen_user(const char *);

extern int __strnlen_user(const char *, long len);

extern __inline__ int strlen_user(const char *str)

{

        if(!access_ok(VERIFY_READ, str, 0))

                return 0;

        else

                return __strlen_user(str);

}

extern __inline__ int strnlen_user(const char *str, long len)

{

        if(!access_ok(VERIFY_READ, str, 0))

                return 0;

        else

                return __strnlen_user(str, len);

}

#endif  /* __ASSEMBLY__ */

#endif /* _ASM_UACCESS_H */