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/* $Id: uaccess.h,v 1.35 2002/02/09 19:49:31 davem Exp $ */
#ifndef _ASM_UACCESS_H
#define _ASM_UACCESS_H
/*
* User space memory access functions
*/
#ifdef __KERNEL__
#include <linux/compiler.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <asm/a.out.h>
#include <asm/asi.h>
#include <asm/system.h>
#include <asm/spitfire.h>
#include <asm-generic/uaccess.h>
#endif
#ifndef __ASSEMBLY__
/*
* Sparc64 is segmented, though more like the M68K than the I386.
* We use the secondary ASI to address user memory, which references a
* completely different VM map, thus there is zero chance of the user
* doing something queer and tricking us into poking kernel memory.
*
* What is left here is basically what is needed for the other parts of
* the kernel that expect to be able to manipulate, erum, "segments".
* Or perhaps more properly, permissions.
*
* "For historical reasons, these macros are grossly misnamed." -Linus
*/
#define KERNEL_DS ((mm_segment_t) { ASI_P })
#define USER_DS ((mm_segment_t) { ASI_AIUS }) /* har har har */
#define VERIFY_READ 0
#define VERIFY_WRITE 1
#define get_fs() ((mm_segment_t) { get_thread_current_ds() })
#define get_ds() (KERNEL_DS)
#define segment_eq(a,b) ((a).seg == (b).seg)
#define set_fs(val) \
do { \
set_thread_current_ds((val).seg); \
__asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg)); \
} while(0)
static inline int __access_ok(const void __user * addr, unsigned long size)
{
return 1;
}
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 int insn, fixup;
};
extern void __ret_efault(void);
extern void __retl_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 ugliness from the user.
*/
#define put_user(x,ptr) ({ \
unsigned long __pu_addr = (unsigned long)(ptr); \
__chk_user_ptr(ptr); \
__put_user_nocheck((__typeof__(*(ptr)))(x),__pu_addr,sizeof(*(ptr))); })
#define get_user(x,ptr) ({ \
unsigned long __gu_addr = (unsigned long)(ptr); \
__chk_user_ptr(ptr); \
__get_user_nocheck((x),__gu_addr,sizeof(*(ptr)),__typeof__(*(ptr))); })
#define __put_user(x,ptr) put_user(x,ptr)
#define __get_user(x,ptr) get_user(x,ptr)
struct __large_struct { unsigned long buf[100]; };
#define __m(x) ((struct __large_struct *)(x))
#define __put_user_nocheck(data,addr,size) ({ \
register int __pu_ret; \
switch (size) { \
case 1: __put_user_asm(data,b,addr,__pu_ret); break; \
case 2: __put_user_asm(data,h,addr,__pu_ret); break; \
case 4: __put_user_asm(data,w,addr,__pu_ret); break; \
case 8: __put_user_asm(data,x,addr,__pu_ret); break; \
default: __pu_ret = __put_user_bad(); break; \
} __pu_ret; })
#define __put_user_asm(x,size,addr,ret) \
__asm__ __volatile__( \
"/* Put user asm, inline. */\n" \
"1:\t" "st"#size "a %1, [%2] %%asi\n\t" \
"clr %0\n" \
"2:\n\n\t" \
".section .fixup,#alloc,#execinstr\n\t" \
".align 4\n" \
"3:\n\t" \
"sethi %%hi(2b), %0\n\t" \
"jmpl %0 + %%lo(2b), %%g0\n\t" \
" mov %3, %0\n\n\t" \
".previous\n\t" \
".section __ex_table,\"a\"\n\t" \
".align 4\n\t" \
".word 1b, 3b\n\t" \
".previous\n\n\t" \
: "=r" (ret) : "r" (x), "r" (__m(addr)), \
"i" (-EFAULT))
extern int __put_user_bad(void);
#define __get_user_nocheck(data,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,uw,addr,__gu_ret); break; \
case 8: __get_user_asm(__gu_val,x,addr,__gu_ret); break; \
default: __gu_val = 0; __gu_ret = __get_user_bad(); break; \
} data = (type) __gu_val; __gu_ret; })
#define __get_user_nocheck_ret(data,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,uw,addr,retval); break; \
case 8: __get_user_asm_ret(__gu_val,x,addr,retval); break; \
default: if (__get_user_bad()) return retval; \
} data = (type) __gu_val; })
#define __get_user_asm(x,size,addr,ret) \
__asm__ __volatile__( \
"/* Get user asm, inline. */\n" \
"1:\t" "ld"#size "a [%2] %%asi, %1\n\t" \
"clr %0\n" \
"2:\n\n\t" \
".section .fixup,#alloc,#execinstr\n\t" \
".align 4\n" \
"3:\n\t" \
"sethi %%hi(2b), %0\n\t" \
"clr %1\n\t" \
"jmpl %0 + %%lo(2b), %%g0\n\t" \
" mov %3, %0\n\n\t" \
".previous\n\t" \
".section __ex_table,\"a\"\n\t" \
".align 4\n\t" \
".word 1b, 3b\n\n\t" \
".previous\n\t" \
: "=r" (ret), "=r" (x) : "r" (__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 "a [%1] %%asi, %0\n\n\t" \
".section __ex_table,\"a\"\n\t" \
".align 4\n\t" \
".word 1b,__ret_efault\n\n\t" \
".previous\n\t" \
: "=r" (x) : "r" (__m(addr))); \
else \
__asm__ __volatile__( \
"/* Get user asm ret, inline. */\n" \
"1:\t" "ld"#size "a [%1] %%asi, %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,\"a\"\n\t" \
".align 4\n\t" \
".word 1b, 3b\n\n\t" \
".previous\n\t" \
: "=r" (x) : "r" (__m(addr)), "i" (retval))
extern int __get_user_bad(void);
extern unsigned long __must_check ___copy_from_user(void *to,
const void __user *from,
unsigned long size);
extern unsigned long copy_from_user_fixup(void *to, const void __user *from,
unsigned long size);
static inline unsigned long __must_check
copy_from_user(void *to, const void __user *from, unsigned long size)
{
unsigned long ret = ___copy_from_user(to, from, size);
if (unlikely(ret))
ret = copy_from_user_fixup(to, from, size);
return ret;
}
#define __copy_from_user copy_from_user
extern unsigned long __must_check ___copy_to_user(void __user *to,
const void *from,
unsigned long size);
extern unsigned long copy_to_user_fixup(void __user *to, const void *from,
unsigned long size);
static inline unsigned long __must_check
copy_to_user(void __user *to, const void *from, unsigned long size)
{
unsigned long ret = ___copy_to_user(to, from, size);
if (unlikely(ret))
ret = copy_to_user_fixup(to, from, size);
return ret;
}
#define __copy_to_user copy_to_user
extern unsigned long __must_check ___copy_in_user(void __user *to,
const void __user *from,
unsigned long size);
extern unsigned long copy_in_user_fixup(void __user *to, void __user *from,
unsigned long size);
static inline unsigned long __must_check
copy_in_user(void __user *to, void __user *from, unsigned long size)
{
unsigned long ret = ___copy_in_user(to, from, size);
if (unlikely(ret))
ret = copy_in_user_fixup(to, from, size);
return ret;
}
#define __copy_in_user copy_in_user
extern unsigned long __must_check __clear_user(void __user *, unsigned long);
#define clear_user __clear_user
extern long __must_check __strncpy_from_user(char *dest, const char __user *src, long count);
#define strncpy_from_user __strncpy_from_user
extern long __strlen_user(const char __user *);
extern long __strnlen_user(const char __user *, long len);
#define strlen_user __strlen_user
#define strnlen_user __strnlen_user
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
#endif /* __ASSEMBLY__ */
#endif /* _ASM_UACCESS_H */
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