/*
* include/asm-s390/uaccess.h
*
* S390 version
* Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Hartmut Penner (hp@de.ibm.com),
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*
* Derived from "include/asm-i386/uaccess.h"
*/
#ifndef __S390_UACCESS_H
#define __S390_UACCESS_H
/*
* User space memory access functions
*/
#include <linux/sched.h>
#include <linux/errno.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(a) ((mm_segment_t) { (a) })
#define KERNEL_DS MAKE_MM_SEG(0)
#define USER_DS MAKE_MM_SEG(1)
#define get_ds() (KERNEL_DS)
#define get_fs() ({ mm_segment_t __x; \
asm volatile("ear %0,4":"=a" (__x)); \
__x;})
#define set_fs(x) ({asm volatile("sar 4,%0"::"a" ((x).ar4));})
#define segment_eq(a,b) ((a).ar4 == (b).ar4)
#define __access_ok(addr,size) (1)
#define access_ok(type,addr,size) __access_ok(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.
*/
struct exception_table_entry
{
unsigned long insn, fixup;
};
/*
* Standard fixup section for uaccess inline functions.
* local label 0: is the fault point
* local label 1: is the return point
* %0 is the error variable
* %3 is the error value -EFAULT
*/
#ifndef __s390x__
#define __uaccess_fixup \
".section .fixup,\"ax\"\n" \
"8: sacf 0\n" \
" lhi %0,%h3\n" \
" bras 4,9f\n" \
" .long 1b\n" \
"9: l 4,0(4)\n" \
" br 4\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 4\n" \
" .long 0b,8b\n" \
".previous"
#else /* __s390x__ */
#define __uaccess_fixup \
".section .fixup,\"ax\"\n" \
"9: sacf 0\n" \
" lhi %0,%h3\n" \
" jg 1b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align 8\n" \
" .quad 0b,9b\n" \
".previous"
#endif /* __s390x__ */
/*
* These are the main single-value transfer routines. They automatically
* use the right size if we just have the right pointer type.
*/
#ifndef __s390x__
#define __put_user_asm_8(x, ptr, err) \
({ \
register __typeof__(x) const * __from asm("2"); \
register __typeof__(*(ptr)) * __to asm("4"); \
__from = &(x); \
__to = (ptr); \
__asm__ __volatile__ ( \
" sacf 512\n" \
"0: mvc 0(8,%1),0(%2)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err) \
: "a" (__to),"a" (__from),"K" (-EFAULT),"0" (0) \
: "cc" ); \
})
#else /* __s390x__ */
#define __put_user_asm_8(x, ptr, err) \
({ \
register __typeof__(*(ptr)) * __ptr asm("4"); \
__ptr = (ptr); \
__asm__ __volatile__ ( \
" sacf 512\n" \
"0: stg %2,0(%1)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err) \
: "a" (__ptr), "d" (x), "K" (-EFAULT), "0" (0) \
: "cc" ); \
})
#endif /* __s390x__ */
#define __put_user_asm_4(x, ptr, err) \
({ \
register __typeof__(*(ptr)) * __ptr asm("4"); \
__ptr = (ptr); \
__asm__ __volatile__ ( \
" sacf 512\n" \
"0: st %2,0(%1)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err) \
: "a" (__ptr), "d" (x), "K" (-EFAULT), "0" (0) \
: "cc" ); \
})
#define __put_user_asm_2(x, ptr, err) \
({ \
register __typeof__(*(ptr)) * __ptr asm("4"); \
__ptr = (ptr); \
__asm__ __volatile__ ( \
" sacf 512\n" \
"0: sth %2,0(%1)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err) \
: "a" (__ptr), "d" (x), "K" (-EFAULT), "0" (0) \
: "cc" ); \
})
#define __put_user_asm_1(x, ptr, err) \
({ \
register __typeof__(*(ptr)) * __ptr asm("4"); \
__ptr = (ptr); \
__asm__ __volatile__ ( \
" sacf 512\n" \
"0: stc %2,0(%1)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err) \
: "a" (__ptr), "d" (x), "K" (-EFAULT), "0" (0) \
: "cc" ); \
})
#define __put_user(x, ptr) \
({ \
__typeof__(*(ptr)) __x = (x); \
int __pu_err; \
switch (sizeof (*(ptr))) { \
case 1: \
__put_user_asm_1(__x, ptr, __pu_err); \
break; \
case 2: \
__put_user_asm_2(__x, ptr, __pu_err); \
break; \
case 4: \
__put_user_asm_4(__x, ptr, __pu_err); \
break; \
case 8: \
__put_user_asm_8(__x, ptr, __pu_err); \
break; \
default: \
__pu_err = __put_user_bad(); \
break; \
} \
__pu_err; \
})
#define put_user(x, ptr) \
({ \
might_sleep(); \
__put_user(x, ptr); \
})
extern int __put_user_bad(void);
#ifndef __s390x__
#define __get_user_asm_8(x, ptr, err) \
({ \
register __typeof__(*(ptr)) const * __from asm("4"); \
register __typeof__(x) * __to asm("2"); \
__from = (ptr); \
__to = &(x); \
__asm__ __volatile__ ( \
" sacf 512\n" \
"0: mvc 0(8,%2),0(%4)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err), "=m" (x) \
: "a" (__to),"K" (-EFAULT),"a" (__from),"0" (0) \
: "cc" ); \
})
#else /* __s390x__ */
#define __get_user_asm_8(x, ptr, err) \
({ \
register __typeof__(*(ptr)) const * __ptr asm("4"); \
__ptr = (ptr); \
__asm__ __volatile__ ( \
" sacf 512\n" \
"0: lg %1,0(%2)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err), "=d" (x) \
: "a" (__ptr), "K" (-EFAULT), "0" (0) \
: "cc" ); \
})
#endif /* __s390x__ */
#define __get_user_asm_4(x, ptr, err) \
({ \
register __typeof__(*(ptr)) const * __ptr asm("4"); \
__ptr = (ptr); \
__asm__ __volatile__ ( \
" sacf 512\n" \
"0: l %1,0(%2)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err), "=d" (x) \
: "a" (__ptr), "K" (-EFAULT), "0" (0) \
: "cc" ); \
})
#define __get_user_asm_2(x, ptr, err) \
({ \
register __typeof__(*(ptr)) const * __ptr asm("4"); \
__ptr = (ptr); \
__asm__ __volatile__ ( \
" sacf 512\n" \
"0: lh %1,0(%2)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err), "=d" (x) \
: "a" (__ptr), "K" (-EFAULT), "0" (0) \
: "cc" ); \
})
#define __get_user_asm_1(x, ptr, err) \
({ \
register __typeof__(*(ptr)) const * __ptr asm("4"); \
__ptr = (ptr); \
__asm__ __volatile__ ( \
" sr %1,%1\n" \
" sacf 512\n" \
"0: ic %1,0(%2)\n" \
" sacf 0\n" \
"1:\n" \
__uaccess_fixup \
: "=&d" (err), "=&d" (x) \
: "a" (__ptr), "K" (-EFAULT), "0" (0) \
: "cc" ); \
})
#define __get_user(x, ptr) \
({ \
__typeof__(*(ptr)) __x; \
int __gu_err; \
switch (sizeof(*(ptr))) { \
case 1: \
__get_user_asm_1(__x, ptr, __gu_err); \
break; \
case 2: \
__get_user_asm_2(__x, ptr, __gu_err); \
break; \
case 4: \
__get_user_asm_4(__x, ptr, __gu_err); \
break; \
case 8: \
__get_user_asm_8(__x, ptr, __gu_err); \
break; \
default: \
__x = 0; \
__gu_err = __get_user_bad(); \
break; \
} \
(x) = __x; \
__gu_err; \
})
#define get_user(x, ptr) \
({ \
might_sleep(); \
__get_user(x, ptr); \
})
extern int __get_user_bad(void);
/*
* access register are set up, that 4 points to secondary (user),
* 2 to primary (kernel)
*/
extern long __copy_to_user_asm(const void *from, long n, const void *to);
#define __copy_to_user(to, from, n) \
({ \
__copy_to_user_asm(from, n, to); \
})
#define copy_to_user(to, from, n) \
({ \
long err = 0; \
__typeof__(n) __n = (n); \
might_sleep(); \
if (__access_ok(to,__n)) { \
err = __copy_to_user_asm(from, __n, to); \
} \
else \
err = __n; \
err; \
})
extern long __copy_from_user_asm(void *to, long n, const void *from);
#define __copy_from_user(to, from, n) \
({ \
__copy_from_user_asm(to, n, from); \
})
#define copy_from_user(to, from, n) \
({ \
long err = 0; \
__typeof__(n) __n = (n); \
might_sleep(); \
if (__access_ok(from,__n)) { \
err = __copy_from_user_asm(to, __n, from); \
} \
else \
err = __n; \
err; \
})
/*
* Copy a null terminated string from userspace.
*/
#ifndef __s390x__
static inline long
__strncpy_from_user(char *dst, const char *src, long count)
{
int len;
__asm__ __volatile__ (
" slr %0,%0\n"
" lr 2,%1\n"
" lr 4,%2\n"
" slr 3,3\n"
" sacf 512\n"
"0: ic 3,0(%0,4)\n"
"1: stc 3,0(%0,2)\n"
" ltr 3,3\n"
" jz 2f\n"
" ahi %0,1\n"
" clr %0,%3\n"
" jl 0b\n"
"2: sacf 0\n"
".section .fixup,\"ax\"\n"
"3: lhi %0,%h4\n"
" basr 3,0\n"
" l 3,4f-.(3)\n"
" br 3\n"
"4: .long 2b\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .align 4\n"
" .long 0b,3b\n"
" .long 1b,3b\n"
".previous"
: "=&a" (len)
: "a" (dst), "d" (src), "d" (count), "K" (-EFAULT)
: "2", "3", "4", "memory", "cc" );
return len;
}
#else /* __s390x__ */
static inline long
__strncpy_from_user(char *dst, const char *src, long count)
{
long len;
__asm__ __volatile__ (
" slgr %0,%0\n"
" lgr 2,%1\n"
" lgr 4,%2\n"
" slr 3,3\n"
" sacf 512\n"
"0: ic 3,0(%0,4)\n"
"1: stc 3,0(%0,2)\n"
" ltr 3,3\n"
" jz 2f\n"
" aghi %0,1\n"
" cgr %0,%3\n"
" jl 0b\n"
"2: sacf 0\n"
".section .fixup,\"ax\"\n"
"3: lghi %0,%h4\n"
" jg 2b\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .align 8\n"
" .quad 0b,3b\n"
" .quad 1b,3b\n"
".previous"
: "=&a" (len)
: "a" (dst), "d" (src), "d" (count), "K" (-EFAULT)
: "cc", "2" ,"3", "4" );
return len;
}
#endif /* __s390x__ */
static inline long
strncpy_from_user(char *dst, const char *src, long count)
{
long res = -EFAULT;
might_sleep();
if (access_ok(VERIFY_READ, src, 1))
res = __strncpy_from_user(dst, src, count);
return res;
}
/*
* Return the size of a string (including the ending 0)
*
* Return 0 for error
*/
#ifndef __s390x__
static inline unsigned long
strnlen_user(const char * src, unsigned long n)
{
might_sleep();
__asm__ __volatile__ (
" alr %0,%1\n"
" slr 0,0\n"
" lr 4,%1\n"
" sacf 512\n"
"0: srst %0,4\n"
" jo 0b\n"
" slr %0,%1\n"
" ahi %0,1\n"
" sacf 0\n"
"1:\n"
".section .fixup,\"ax\"\n"
"2: sacf 0\n"
" slr %0,%0\n"
" bras 4,3f\n"
" .long 1b\n"
"3: l 4,0(4)\n"
" br 4\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .align 4\n"
" .long 0b,2b\n"
".previous"
: "+&a" (n) : "d" (src)
: "cc", "0", "4" );
return n;
}
#else /* __s390x__ */
static inline unsigned long
strnlen_user(const char * src, unsigned long n)
{
might_sleep();
#if 0
__asm__ __volatile__ (
" algr %0,%1\n"
" slgr 0,0\n"
" lgr 4,%1\n"
" sacf 512\n"
"0: srst %0,4\n"
" jo 0b\n"
" slgr %0,%1\n"
" aghi %0,1\n"
"1: sacf 0\n"
".section .fixup,\"ax\"\n"
"2: slgr %0,%0\n"
" jg 1b\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .align 8\n"
" .quad 0b,2b\n"
".previous"
: "+&a" (n) : "d" (src)
: "cc", "0", "4" );
#else
__asm__ __volatile__ (
" lgr 4,%1\n"
" sacf 512\n"
"0: cli 0(4),0x00\n"
" la 4,1(4)\n"
" je 1f\n"
" brctg %0,0b\n"
"1: lgr %0,4\n"
" slgr %0,%1\n"
"2: sacf 0\n"
".section .fixup,\"ax\"\n"
"3: slgr %0,%0\n"
" jg 2b\n"
".previous\n"
".section __ex_table,\"a\"\n"
" .align 8\n"
" .quad 0b,3b\n"
".previous"
: "+&a" (n) : "d" (src)
: "cc", "4" );
#endif
return n;
}
#endif /* __s390x__ */
#define strlen_user(str) strnlen_user(str, ~0UL)
/*
* Zero Userspace
*/
extern long __clear_user_asm(void *to, long n);
#define __clear_user(to, n) \
({ \
__clear_user_asm(to, n); \
})
static inline unsigned long
clear_user(void *to, unsigned long n)
{
might_sleep();
if (access_ok(VERIFY_WRITE, to, n))
n = __clear_user(to, n);
return n;
}
#endif /* _S390_UACCESS_H */
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