#ifndef _ARCH_POWERPC_UACCESS_H
#define _ARCH_POWERPC_UACCESS_H
#ifdef __KERNEL__
#ifndef __ASSEMBLY__
#include <linux/sched.h>
#include <linux/errno.h>
#include <asm/processor.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.
*
* The fs/ds values are now the highest legal address in the "segment".
* This simplifies the checking in the routines below.
*/
#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
#define KERNEL_DS MAKE_MM_SEG(~0UL)
#ifdef __powerpc64__
/* We use TASK_SIZE_USER64 as TASK_SIZE is not constant */
#define USER_DS MAKE_MM_SEG(TASK_SIZE_USER64 - 1)
#else
#define USER_DS MAKE_MM_SEG(TASK_SIZE - 1)
#endif
#define get_ds() (KERNEL_DS)
#define get_fs() (current->thread.fs)
#define set_fs(val) (current->thread.fs = (val))
#define segment_eq(a, b) ((a).seg == (b).seg)
#ifdef __powerpc64__
/*
* This check is sufficient because there is a large enough
* gap between user addresses and the kernel addresses
*/
#define __access_ok(addr, size, segment) \
(((addr) <= (segment).seg) && ((size) <= (segment).seg))
#else
#define __access_ok(addr, size, segment) \
(((addr) <= (segment).seg) && \
(((size) == 0) || (((size) - 1) <= ((segment).seg - (addr)))))
#endif
#define access_ok(type, addr, size) \
(__chk_user_ptr(addr), \
__access_ok((__force unsigned long)(addr), (size), get_fs()))
/*
* 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;
unsigned long 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 the
* PowerPC, we can just do these as direct assignments. (Of course, the
* exception handling means that it's no longer "just"...)
*
* The "user64" versions of the user access functions are versions that
* allow access of 64-bit data. The "get_user" functions do not
* properly handle 64-bit data because the value gets down cast to a long.
* The "put_user" functions already handle 64-bit data properly but we add
* "user64" versions for completeness
*/
#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)))
#ifndef __powerpc64__
#define __get_user64(x, ptr) \
__get_user64_nocheck((x), (ptr), sizeof(*(ptr)))
#define __put_user64(x, ptr) __put_user(x, ptr)
#endif
#ifdef __powerpc64__
#define __get_user_unaligned __get_user
#define __put_user_unaligned __put_user
#endif
extern long __put_user_bad(void);
#ifdef __powerpc64__
#define __EX_TABLE_ALIGN "3"
#define __EX_TABLE_TYPE "llong"
#else
#define __EX_TABLE_ALIGN "2"
#define __EX_TABLE_TYPE "long"
#endif
/*
* We don't tell gcc that we are accessing memory, but this is OK
* because we do not write to any memory gcc knows about, so there
* are no aliasing issues.
*/
#define __put_user_asm(x, addr, err, op) \
__asm__ __volatile__( \
"1: " op " %1,0(%2) # put_user\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: li %0,%3\n" \
" b 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align " __EX_TABLE_ALIGN "\n" \
" ."__EX_TABLE_TYPE" 1b,3b\n" \
".previous" \
: "=r" (err) \
: "r" (x), "b" (addr), "i" (-EFAULT), "0" (err))
#ifdef __powerpc64__
#define __put_user_asm2(x, ptr, retval) \
__put_user_asm(x, ptr, retval, "std")
#else /* __powerpc64__ */
#define __put_user_asm2(x, addr, err) \
__asm__ __volatile__( \
"1: stw %1,0(%2)\n" \
"2: stw %1+1,4(%2)\n" \
"3:\n" \
".section .fixup,\"ax\"\n" \
"4: li %0,%3\n" \
" b 3b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align " __EX_TABLE_ALIGN "\n" \
" ." __EX_TABLE_TYPE " 1b,4b\n" \
" ." __EX_TABLE_TYPE " 2b,4b\n" \
".previous" \
: "=r" (err) \
: "r" (x), "b" (addr), "i" (-EFAULT), "0" (err))
#endif /* __powerpc64__ */
#define __put_user_size(x, ptr, size, retval) \
do { \
retval = 0; \
switch (size) { \
case 1: __put_user_asm(x, ptr, retval, "stb"); break; \
case 2: __put_user_asm(x, ptr, retval, "sth"); break; \
case 4: __put_user_asm(x, ptr, retval, "stw"); break; \
case 8: __put_user_asm2(x, ptr, retval); break; \
default: __put_user_bad(); \
} \
} while (0)
#define __put_user_nocheck(x, ptr, size) \
({ \
long __pu_err; \
might_sleep(); \
__chk_user_ptr(ptr); \
__put_user_size((x), (ptr), (size), __pu_err); \
__pu_err; \
})
#define __put_user_check(x, ptr, size) \
({ \
long __pu_err = -EFAULT; \
__typeof__(*(ptr)) __user *__pu_addr = (ptr); \
might_sleep(); \
if (access_ok(VERIFY_WRITE, __pu_addr, size)) \
__put_user_size((x), __pu_addr, (size), __pu_err); \
__pu_err; \
})
extern long __get_user_bad(void);
#define __get_user_asm(x, addr, err, op) \
__asm__ __volatile__( \
"1: "op" %1,0(%2) # get_user\n" \
"2:\n" \
".section .fixup,\"ax\"\n" \
"3: li %0,%3\n" \
" li %1,0\n" \
" b 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align "__EX_TABLE_ALIGN "\n" \
" ." __EX_TABLE_TYPE " 1b,3b\n" \
".previous" \
: "=r" (err), "=r" (x) \
: "b" (addr), "i" (-EFAULT), "0" (err))
#ifdef __powerpc64__
#define __get_user_asm2(x, addr, err) \
__get_user_asm(x, addr, err, "ld")
#else /* __powerpc64__ */
#define __get_user_asm2(x, addr, err) \
__asm__ __volatile__( \
"1: lwz %1,0(%2)\n" \
"2: lwz %1+1,4(%2)\n" \
"3:\n" \
".section .fixup,\"ax\"\n" \
"4: li %0,%3\n" \
" li %1,0\n" \
" li %1+1,0\n" \
" b 3b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .align " __EX_TABLE_ALIGN "\n" \
" ." __EX_TABLE_TYPE " 1b,4b\n" \
" ." __EX_TABLE_TYPE " 2b,4b\n" \
".previous" \
: "=r" (err), "=&r" (x) \
: "b" (addr), "i" (-EFAULT), "0" (err))
#endif /* __powerpc64__ */
#define __get_user_size(x, ptr, size, retval) \
do { \
retval = 0; \
__chk_user_ptr(ptr); \
if (size > sizeof(x)) \
(x) = __get_user_bad(); \
switch (size) { \
case 1: __get_user_asm(x, ptr, retval, "lbz"); break; \
case 2: __get_user_asm(x, ptr, retval, "lhz"); break; \
case 4: __get_user_asm(x, ptr, retval, "lwz"); break; \
case 8: __get_user_asm2(x, ptr, retval); break; \
default: (x) = __get_user_bad(); \
} \
} while (0)
#define __get_user_nocheck(x, ptr, size) \
({ \
long __gu_err; \
unsigned long __gu_val; \
__chk_user_ptr(ptr); \
might_sleep(); \
__get_user_size(__gu_val, (ptr), (size), __gu_err); \
(x) = (__typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
#ifndef __powerpc64__
#define __get_user64_nocheck(x, ptr, size) \
({ \
long __gu_err; \
long long __gu_val; \
__chk_user_ptr(ptr); \
might_sleep(); \
__get_user_size(__gu_val, (ptr), (size), __gu_err); \
(x) = (__typeof__(*(ptr)))__gu_val; \
__gu_err; \
})
#endif /* __powerpc64__ */
#define __get_user_check(x, ptr, size) \
({ \
long __gu_err = -EFAULT; \
unsigned long __gu_val = 0; \
const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
might_sleep(); \
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; \
})
/* more complex routines */
extern unsigned long __copy_tofrom_user(void __user *to,
const void __user *from, unsigned long size);
#ifndef __powerpc64__
extern inline unsigned long copy_from_user(void *to,
const void __user *from, unsigned long n)
{
unsigned long over;
if (access_ok(VERIFY_READ, from, n))
return __copy_tofrom_user((__force void __user *)to, from, n);
if ((unsigned long)from < TASK_SIZE) {
over = (unsigned long)from + n - TASK_SIZE;
return __copy_tofrom_user((__force void __user *)to, from,
n - over) + over;
}
return n;
}
extern inline unsigned long copy_to_user(void __user *to,
const void *from, unsigned long n)
{
unsigned long over;
if (access_ok(VERIFY_WRITE, to, n))
return __copy_tofrom_user(to, (__force void __user *)from, n);
if ((unsigned long)to < TASK_SIZE) {
over = (unsigned long)to + n - TASK_SIZE;
return __copy_tofrom_user(to, (__force void __user *)from,
n - over) + over;
}
return n;
}
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
#else /* __powerpc64__ */
#define __copy_in_user(to, from, size) \
__copy_tofrom_user((to), (from), (size))
extern unsigned long copy_from_user(void *to, const void __user *from,
unsigned long n);
extern unsigned long copy_to_user(void __user *to, const void *from,
unsigned long n);
extern unsigned long copy_in_user(void __user *to, const void __user *from,
unsigned long n);
static inline unsigned long __copy_from_user_inatomic(void *to,
const void __user *from, unsigned long n)
{
if (__builtin_constant_p(n) && (n <= 8)) {
unsigned long ret;
switch (n) {
case 1:
__get_user_size(*(u8 *)to, from, 1, ret);
break;
case 2:
__get_user_size(*(u16 *)to, from, 2, ret);
break;
case 4:
__get_user_size(*(u32 *)to, from, 4, ret);
break;
case 8:
__get_user_size(*(u64 *)to, from, 8, ret);
break;
}
return (ret == -EFAULT) ? n : 0;
}
return __copy_tofrom_user((__force void __user *) to, from, n);
}
static inline unsigned long __copy_to_user_inatomic(void __user *to,
const void *from, unsigned long n)
{
if (__builtin_constant_p(n) && (n <= 8)) {
unsigned long ret;
switch (n) {
case 1:
__put_user_size(*(u8 *)from, (u8 __user *)to, 1, ret);
break;
case 2:
__put_user_size(*(u16 *)from, (u16 __user *)to, 2, ret);
break;
case 4:
__put_user_size(*(u32 *)from, (u32 __user *)to, 4, ret);
break;
case 8:
__put_user_size(*(u64 *)from, (u64 __user *)to, 8, ret);
break;
}
return (ret == -EFAULT) ? n : 0;
}
return __copy_tofrom_user(to, (__force const void __user *) from, n);
}
#endif /* __powerpc64__ */
static inline unsigned long __copy_from_user(void *to,
const void __user *from, unsigned long size)
{
might_sleep();
#ifndef __powerpc64__
return __copy_tofrom_user((__force void __user *)to, from, size);
#else /* __powerpc64__ */
return __copy_from_user_inatomic(to, from, size);
#endif /* __powerpc64__ */
}
static inline unsigned long __copy_to_user(void __user *to,
const void *from, unsigned long size)
{
might_sleep();
#ifndef __powerpc64__
return __copy_tofrom_user(to, (__force void __user *)from, size);
#else /* __powerpc64__ */
return __copy_to_user_inatomic(to, from, size);
#endif /* __powerpc64__ */
}
extern unsigned long __clear_user(void __user *addr, unsigned long size);
static inline unsigned long clear_user(void __user *addr, unsigned long size)
{
might_sleep();
if (likely(access_ok(VERIFY_WRITE, addr, size)))
return __clear_user(addr, size);
#ifndef __powerpc64__
if ((unsigned long)addr < TASK_SIZE) {
unsigned long over = (unsigned long)addr + size - TASK_SIZE;
return __clear_user(addr, size - over) + over;
}
#endif /* __powerpc64__ */
return size;
}
extern int __strncpy_from_user(char *dst, const char __user *src, long count);
static inline long strncpy_from_user(char *dst, const char __user *src,
long count)
{
might_sleep();
if (likely(access_ok(VERIFY_READ, src, 1)))
return __strncpy_from_user(dst, src, count);
return -EFAULT;
}
/*
* Return the size of a string (including the ending 0)
*
* Return 0 for error
*/
extern int __strnlen_user(const char __user *str, long len, unsigned long top);
/*
* Returns the length of the string at str (including the null byte),
* or 0 if we hit a page we can't access,
* or something > len if we didn't find a null byte.
*
* The `top' parameter to __strnlen_user is to make sure that
* we can never overflow from the user area into kernel space.
*/
static inline int strnlen_user(const char __user *str, long len)
{
unsigned long top = current->thread.fs.seg;
if ((unsigned long)str > top)
return 0;
return __strnlen_user(str, len, top);
}
#define strlen_user(str) strnlen_user((str), 0x7ffffffe)
#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* _ARCH_POWERPC_UACCESS_H */
