kernel-ark/include/asm-cris/uaccess.h
Jesper Nilsson 07f2402b4a cris: correct usage of __user for copy to and from user space in lib/usercopy and uaccess.h
Function __copy_user_zeroing in arch/lib/usercopy.c had the wrong parameter
set as __user, and in include/asm-cris/uaccess.h, it was not set at all for
some of the calling functions.

This will cut the number of warnings quite dramatically when using sparse.

While we're here, remove useless CVS log and correct confusing typo.

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <mikael.starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-04 16:35:16 -08:00

405 lines
11 KiB
C

/*
* Authors: Bjorn Wesen (bjornw@axis.com)
* Hans-Peter Nilsson (hp@axis.com)
*/
/* Asm:s have been tweaked (within the domain of correctness) to give
satisfactory results for "gcc version 2.96 20000427 (experimental)".
Check regularly...
Register $r9 is chosen for temporaries, being a call-clobbered register
first in line to be used (notably for local blocks), not colliding with
parameter registers. */
#ifndef _CRIS_UACCESS_H
#define _CRIS_UACCESS_H
#ifndef __ASSEMBLY__
#include <linux/sched.h>
#include <linux/errno.h>
#include <asm/processor.h>
#include <asm/page.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(s) ((mm_segment_t) { (s) })
/* addr_limit is the maximum accessible address for the task. we misuse
* the KERNEL_DS and USER_DS values to both assign and compare the
* addr_limit values through the equally misnamed get/set_fs macros.
* (see above)
*/
#define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF)
#define USER_DS MAKE_MM_SEG(TASK_SIZE)
#define get_ds() (KERNEL_DS)
#define get_fs() (current_thread_info()->addr_limit)
#define set_fs(x) (current_thread_info()->addr_limit = (x))
#define segment_eq(a,b) ((a).seg == (b).seg)
#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))
#define __user_ok(addr,size) (((size) <= TASK_SIZE)&&((addr) <= TASK_SIZE-(size)))
#define __access_ok(addr,size) (__kernel_ok || __user_ok((addr),(size)))
#define access_ok(type,addr,size) __access_ok((unsigned long)(addr),(size))
#include <asm/arch/uaccess.h>
/*
* 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;
};
/*
* These are 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.
*
* The "__xxx" versions of the user access functions are versions that
* do not verify the address space, that must have been done previously
* with a separate "access_ok()" call (this is used when we do multiple
* accesses to the same area of user memory).
*
* As we use the same address space for kernel and user data on
* CRIS, we can just do these as direct assignments. (Of course, the
* exception handling means that it's no longer "just"...)
*/
#define get_user(x,ptr) \
__get_user_check((x),(ptr),sizeof(*(ptr)))
#define put_user(x,ptr) \
__put_user_check((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
#define __get_user(x,ptr) \
__get_user_nocheck((x),(ptr),sizeof(*(ptr)))
#define __put_user(x,ptr) \
__put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
extern long __put_user_bad(void);
#define __put_user_size(x,ptr,size,retval) \
do { \
retval = 0; \
switch (size) { \
case 1: __put_user_asm(x,ptr,retval,"move.b"); break; \
case 2: __put_user_asm(x,ptr,retval,"move.w"); break; \
case 4: __put_user_asm(x,ptr,retval,"move.d"); break; \
case 8: __put_user_asm_64(x,ptr,retval); break; \
default: __put_user_bad(); \
} \
} while (0)
#define __get_user_size(x,ptr,size,retval) \
do { \
retval = 0; \
switch (size) { \
case 1: __get_user_asm(x,ptr,retval,"move.b"); break; \
case 2: __get_user_asm(x,ptr,retval,"move.w"); break; \
case 4: __get_user_asm(x,ptr,retval,"move.d"); break; \
case 8: __get_user_asm_64(x,ptr,retval); break; \
default: (x) = __get_user_bad(); \
} \
} while (0)
#define __put_user_nocheck(x,ptr,size) \
({ \
long __pu_err; \
__put_user_size((x),(ptr),(size),__pu_err); \
__pu_err; \
})
#define __put_user_check(x,ptr,size) \
({ \
long __pu_err = -EFAULT; \
__typeof__(*(ptr)) *__pu_addr = (ptr); \
if (access_ok(VERIFY_WRITE,__pu_addr,size)) \
__put_user_size((x),__pu_addr,(size),__pu_err); \
__pu_err; \
})
struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct *)(x))
#define __get_user_nocheck(x,ptr,size) \
({ \
long __gu_err, __gu_val; \
__get_user_size(__gu_val,(ptr),(size),__gu_err); \
(x) = (__typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
#define __get_user_check(x,ptr,size) \
({ \
long __gu_err = -EFAULT, __gu_val = 0; \
const __typeof__(*(ptr)) *__gu_addr = (ptr); \
if (access_ok(VERIFY_READ,__gu_addr,size)) \
__get_user_size(__gu_val,__gu_addr,(size),__gu_err); \
(x) = (__typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
extern long __get_user_bad(void);
/* More complex functions. Most are inline, but some call functions that
live in lib/usercopy.c */
extern unsigned long __copy_user(void __user *to, const void *from, unsigned long n);
extern unsigned long __copy_user_zeroing(void *to, const void __user *from, unsigned long n);
extern unsigned long __do_clear_user(void __user *to, unsigned long n);
static inline unsigned long
__generic_copy_to_user(void __user *to, const void *from, unsigned long n)
{
if (access_ok(VERIFY_WRITE, to, n))
return __copy_user(to,from,n);
return n;
}
static inline unsigned long
__generic_copy_from_user(void *to, const void __user *from, unsigned long n)
{
if (access_ok(VERIFY_READ, from, n))
return __copy_user_zeroing(to,from,n);
return n;
}
static inline unsigned long
__generic_clear_user(void __user *to, unsigned long n)
{
if (access_ok(VERIFY_WRITE, to, n))
return __do_clear_user(to,n);
return n;
}
static inline long
__strncpy_from_user(char *dst, const char __user *src, long count)
{
return __do_strncpy_from_user(dst, src, count);
}
static inline long
strncpy_from_user(char *dst, const char __user *src, long count)
{
long res = -EFAULT;
if (access_ok(VERIFY_READ, src, 1))
res = __do_strncpy_from_user(dst, src, count);
return res;
}
/* Note that these expand awfully if made into switch constructs, so
don't do that. */
static inline unsigned long
__constant_copy_from_user(void *to, const void __user *from, unsigned long n)
{
unsigned long ret = 0;
if (n == 0)
;
else if (n == 1)
__asm_copy_from_user_1(to, from, ret);
else if (n == 2)
__asm_copy_from_user_2(to, from, ret);
else if (n == 3)
__asm_copy_from_user_3(to, from, ret);
else if (n == 4)
__asm_copy_from_user_4(to, from, ret);
else if (n == 5)
__asm_copy_from_user_5(to, from, ret);
else if (n == 6)
__asm_copy_from_user_6(to, from, ret);
else if (n == 7)
__asm_copy_from_user_7(to, from, ret);
else if (n == 8)
__asm_copy_from_user_8(to, from, ret);
else if (n == 9)
__asm_copy_from_user_9(to, from, ret);
else if (n == 10)
__asm_copy_from_user_10(to, from, ret);
else if (n == 11)
__asm_copy_from_user_11(to, from, ret);
else if (n == 12)
__asm_copy_from_user_12(to, from, ret);
else if (n == 13)
__asm_copy_from_user_13(to, from, ret);
else if (n == 14)
__asm_copy_from_user_14(to, from, ret);
else if (n == 15)
__asm_copy_from_user_15(to, from, ret);
else if (n == 16)
__asm_copy_from_user_16(to, from, ret);
else if (n == 20)
__asm_copy_from_user_20(to, from, ret);
else if (n == 24)
__asm_copy_from_user_24(to, from, ret);
else
ret = __generic_copy_from_user(to, from, n);
return ret;
}
/* Ditto, don't make a switch out of this. */
static inline unsigned long
__constant_copy_to_user(void __user *to, const void *from, unsigned long n)
{
unsigned long ret = 0;
if (n == 0)
;
else if (n == 1)
__asm_copy_to_user_1(to, from, ret);
else if (n == 2)
__asm_copy_to_user_2(to, from, ret);
else if (n == 3)
__asm_copy_to_user_3(to, from, ret);
else if (n == 4)
__asm_copy_to_user_4(to, from, ret);
else if (n == 5)
__asm_copy_to_user_5(to, from, ret);
else if (n == 6)
__asm_copy_to_user_6(to, from, ret);
else if (n == 7)
__asm_copy_to_user_7(to, from, ret);
else if (n == 8)
__asm_copy_to_user_8(to, from, ret);
else if (n == 9)
__asm_copy_to_user_9(to, from, ret);
else if (n == 10)
__asm_copy_to_user_10(to, from, ret);
else if (n == 11)
__asm_copy_to_user_11(to, from, ret);
else if (n == 12)
__asm_copy_to_user_12(to, from, ret);
else if (n == 13)
__asm_copy_to_user_13(to, from, ret);
else if (n == 14)
__asm_copy_to_user_14(to, from, ret);
else if (n == 15)
__asm_copy_to_user_15(to, from, ret);
else if (n == 16)
__asm_copy_to_user_16(to, from, ret);
else if (n == 20)
__asm_copy_to_user_20(to, from, ret);
else if (n == 24)
__asm_copy_to_user_24(to, from, ret);
else
ret = __generic_copy_to_user(to, from, n);
return ret;
}
/* No switch, please. */
static inline unsigned long
__constant_clear_user(void __user *to, unsigned long n)
{
unsigned long ret = 0;
if (n == 0)
;
else if (n == 1)
__asm_clear_1(to, ret);
else if (n == 2)
__asm_clear_2(to, ret);
else if (n == 3)
__asm_clear_3(to, ret);
else if (n == 4)
__asm_clear_4(to, ret);
else if (n == 8)
__asm_clear_8(to, ret);
else if (n == 12)
__asm_clear_12(to, ret);
else if (n == 16)
__asm_clear_16(to, ret);
else if (n == 20)
__asm_clear_20(to, ret);
else if (n == 24)
__asm_clear_24(to, ret);
else
ret = __generic_clear_user(to, n);
return ret;
}
#define clear_user(to, n) \
(__builtin_constant_p(n) ? \
__constant_clear_user(to, n) : \
__generic_clear_user(to, n))
#define copy_from_user(to, from, n) \
(__builtin_constant_p(n) ? \
__constant_copy_from_user(to, from, n) : \
__generic_copy_from_user(to, from, n))
#define copy_to_user(to, from, n) \
(__builtin_constant_p(n) ? \
__constant_copy_to_user(to, from, n) : \
__generic_copy_to_user(to, from, n))
/* We let the __ versions of copy_from/to_user inline, because they're often
* used in fast paths and have only a small space overhead.
*/
static inline unsigned long
__generic_copy_from_user_nocheck(void *to, const void __user *from,
unsigned long n)
{
return __copy_user_zeroing(to,from,n);
}
static inline unsigned long
__generic_copy_to_user_nocheck(void __user *to, const void *from,
unsigned long n)
{
return __copy_user(to,from,n);
}
static inline unsigned long
__generic_clear_user_nocheck(void __user *to, unsigned long n)
{
return __do_clear_user(to,n);
}
/* without checking */
#define __copy_to_user(to,from,n) __generic_copy_to_user_nocheck((to),(from),(n))
#define __copy_from_user(to,from,n) __generic_copy_from_user_nocheck((to),(from),(n))
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
#define __clear_user(to,n) __generic_clear_user_nocheck((to),(n))
#define strlen_user(str) strnlen_user((str), 0x7ffffffe)
#endif /* __ASSEMBLY__ */
#endif /* _CRIS_UACCESS_H */