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/* $Id: uaccess.h,v 1.34 2001/09/27 04:36:24 kanoj Exp $ */
#ifndef _ASM_UACCESS_H
#define _ASM_UACCESS_H
/*
* User space memory access functions
*/
#ifdef __KERNEL__
#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>
#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() (current->thread.current_ds)
#define get_ds() (KERNEL_DS)
#define segment_eq(a,b) ((a).seg == (b).seg)
#define set_fs(val) \
do { \
current->thread.current_ds = (val); \
__asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" ((val).seg)); \
} while(0)
#define __user_ok(addr,size) 1
#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))
#define __access_ok(addr,size) 1
#define access_ok(type,addr,size) 1
extern inline int verify_area(int type, const void * addr, unsigned long size)
{
return 0;
}
/*
* 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 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_nocheck((__typeof__(*(ptr)))(x),__pu_addr,sizeof(*(ptr))); })
#define get_user(x,ptr) ({ \
unsigned long __gu_addr = (unsigned long)(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_nocheck_ret(data,addr,size,retval) ({ \
register int __foo __asm__ ("l1"); \
switch (size) { \
case 1: __put_user_asm_ret(data,b,addr,retval,__foo); break; \
case 2: __put_user_asm_ret(data,h,addr,retval,__foo); break; \
case 4: __put_user_asm_ret(data,w,addr,retval,__foo); break; \
case 8: __put_user_asm_ret(data,x,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 "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" \
"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\t" \
".previous\n\n\t" \
: "=r" (ret) : "r" (x), "r" (__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 "a %1, [%2] %%asi\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), "r" (__m(addr))); \
else \
__asm__ __volatile( \
"/* Put user asm ret, inline. */\n" \
"1:\t" "st"#size "a %1, [%2] %%asi\n\n\t" \
".section .fixup,#alloc,#execinstr\n\t" \
".align 4\n" \
"3:\n\t" \
"ret\n\t" \
" restore %%g0, %3, %%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\n\t" \
: "=r" (foo) : "r" (x), "r" (__m(addr)), \
"i" (ret))
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" \
"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) : "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,#alloc\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,#alloc\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 __kernel_size_t __copy_from_user(void *to, const void *from,
__kernel_size_t size);
extern __kernel_size_t __copy_to_user(void *to, const void *from,
__kernel_size_t size);
extern __kernel_size_t __copy_in_user(void *to, const void *from,
__kernel_size_t size);
#define copy_from_user(to,from,n) \
__copy_from_user((void *)(to), \
(void *)(from), (__kernel_size_t)(n))
#define copy_to_user(to,from,n) \
__copy_to_user((void *)(to), \
(void *) (from), (__kernel_size_t)(n))
#define copy_in_user(to,from,n) \
__copy_in_user((void *)(to), \
(void *) (from), (__kernel_size_t)(n))
extern __inline__ __kernel_size_t __clear_user(void *addr, __kernel_size_t size)
{
extern __kernel_size_t __bzero_noasi(void *addr, __kernel_size_t size);
return __bzero_noasi(addr, size);
}
#define clear_user(addr,n) \
__clear_user((void *)(addr), (__kernel_size_t)(n))
extern int __strncpy_from_user(unsigned long dest, unsigned long src, int count);
#define strncpy_from_user(dest,src,count) \
__strncpy_from_user((unsigned long)(dest), (unsigned long)(src), (int)(count))
extern int __strlen_user(const char *);
extern int __strnlen_user(const char *, long len);
#define strlen_user __strlen_user
#define strnlen_user __strnlen_user
#endif /* __ASSEMBLY__ */
#endif /* _ASM_UACCESS_H */
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