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#ifndef __PARISC_UACCESS_H
#define __PARISC_UACCESS_H
/*
* User space memory access functions
*/
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/cache.h>
#include <asm/errno.h>
#include <asm-generic/uaccess-unaligned.h>
#include <linux/sched.h>
#define VERIFY_READ 0
#define VERIFY_WRITE 1
#define KERNEL_DS ((mm_segment_t){0})
#define USER_DS ((mm_segment_t){1})
#define segment_eq(a,b) ((a).seg == (b).seg)
#define get_ds() (KERNEL_DS)
#define get_fs() (current_thread_info()->addr_limit)
#define set_fs(x) (current_thread_info()->addr_limit = (x))
/*
* Note that since kernel addresses are in a separate address space on
* parisc, we don't need to do anything for access_ok().
* We just let the page fault handler do the right thing. This also means
* that put_user is the same as __put_user, etc.
*/
extern int __get_kernel_bad(void);
extern int __get_user_bad(void);
extern int __put_kernel_bad(void);
extern int __put_user_bad(void);
/*
* Test whether a block of memory is a valid user space address.
* Returns 0 if the range is valid, nonzero otherwise.
*/
static inline int __range_not_ok(unsigned long addr, unsigned long size,
unsigned long limit)
{
unsigned long __newaddr = addr + size;
return (__newaddr < addr || __newaddr > limit || size > limit);
}
/**
* access_ok: - Checks if a user space pointer is valid
* @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
* %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
* to write to a block, it is always safe to read from it.
* @addr: User space pointer to start of block to check
* @size: Size of block to check
*
* Context: User context only. This function may sleep.
*
* Checks if a pointer to a block of memory in user space is valid.
*
* Returns true (nonzero) if the memory block may be valid, false (zero)
* if it is definitely invalid.
*
* Note that, depending on architecture, this function probably just
* checks that the pointer is in the user space range - after calling
* this function, memory access functions may still return -EFAULT.
*/
#define access_ok(type, addr, size) \
( __chk_user_ptr(addr), \
!__range_not_ok((unsigned long) (__force void *) (addr), \
size, user_addr_max()) \
)
#define put_user __put_user
#define get_user __get_user
#if !defined(CONFIG_64BIT)
#define LDD_KERNEL(ptr) __get_kernel_bad();
#define LDD_USER(ptr) __get_user_bad();
#define STD_KERNEL(x, ptr) __put_kernel_asm64(x,ptr)
#define STD_USER(x, ptr) __put_user_asm64(x,ptr)
#define ASM_WORD_INSN ".word\t"
#else
#define LDD_KERNEL(ptr) __get_kernel_asm("ldd",ptr)
#define LDD_USER(ptr) __get_user_asm("ldd",ptr)
#define STD_KERNEL(x, ptr) __put_kernel_asm("std",x,ptr)
#define STD_USER(x, ptr) __put_user_asm("std",x,ptr)
#define ASM_WORD_INSN ".dword\t"
#endif
/*
* The exception table contains two values: the first is an address
* for an instruction that is allowed to fault, and the second is
* the address to the fixup routine. Even on a 64bit kernel we could
* use a 32bit (unsigned int) address here.
*/
struct exception_table_entry {
unsigned long insn; /* address of insn that is allowed to fault. */
unsigned long fixup; /* fixup routine */
};
#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
".section __ex_table,\"aw\"\n" \
ASM_WORD_INSN #fault_addr ", " #except_addr "\n\t" \
".previous\n"
/*
* The page fault handler stores, in a per-cpu area, the following information
* if a fixup routine is available.
*/
struct exception_data {
unsigned long fault_ip;
unsigned long fault_space;
unsigned long fault_addr;
};
#define __get_user(x,ptr) \
({ \
register long __gu_err __asm__ ("r8") = 0; \
register long __gu_val __asm__ ("r9") = 0; \
\
if (segment_eq(get_fs(),KERNEL_DS)) { \
switch (sizeof(*(ptr))) { \
case 1: __get_kernel_asm("ldb",ptr); break; \
case 2: __get_kernel_asm("ldh",ptr); break; \
case 4: __get_kernel_asm("ldw",ptr); break; \
case 8: LDD_KERNEL(ptr); break; \
default: __get_kernel_bad(); break; \
} \
} \
else { \
switch (sizeof(*(ptr))) { \
case 1: __get_user_asm("ldb",ptr); break; \
case 2: __get_user_asm("ldh",ptr); break; \
case 4: __get_user_asm("ldw",ptr); break; \
case 8: LDD_USER(ptr); break; \
default: __get_user_bad(); break; \
} \
} \
\
(x) = (__typeof__(*(ptr))) __gu_val; \
__gu_err; \
})
#define __get_kernel_asm(ldx,ptr) \
__asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err) \
: "r1");
#define __get_user_asm(ldx,ptr) \
__asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_get_user_skip_1)\
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err) \
: "r1");
#define __put_user(x,ptr) \
({ \
register long __pu_err __asm__ ("r8") = 0; \
__typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \
\
if (segment_eq(get_fs(),KERNEL_DS)) { \
switch (sizeof(*(ptr))) { \
case 1: __put_kernel_asm("stb",__x,ptr); break; \
case 2: __put_kernel_asm("sth",__x,ptr); break; \
case 4: __put_kernel_asm("stw",__x,ptr); break; \
case 8: STD_KERNEL(__x,ptr); break; \
default: __put_kernel_bad(); break; \
} \
} \
else { \
switch (sizeof(*(ptr))) { \
case 1: __put_user_asm("stb",__x,ptr); break; \
case 2: __put_user_asm("sth",__x,ptr); break; \
case 4: __put_user_asm("stw",__x,ptr); break; \
case 8: STD_USER(__x,ptr); break; \
default: __put_user_bad(); break; \
} \
} \
\
__pu_err; \
})
/*
* The "__put_user/kernel_asm()" macros tell gcc they read from memory
* instead of writing. This is because they do not write to any memory
* gcc knows about, so there are no aliasing issues. These macros must
* also be aware that "fixup_put_user_skip_[12]" are executed in the
* context of the fault, and any registers used there must be listed
* as clobbers. In this case only "r1" is used by the current routines.
* r8/r9 are already listed as err/val.
*/
#define __put_kernel_asm(stx,x,ptr) \
__asm__ __volatile__ ( \
"\n1:\t" stx "\t%2,0(%1)\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err) \
: "r1")
#define __put_user_asm(stx,x,ptr) \
__asm__ __volatile__ ( \
"\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_1)\
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err) \
: "r1")
#if !defined(CONFIG_64BIT)
#define __put_kernel_asm64(__val,ptr) do { \
__asm__ __volatile__ ( \
"\n1:\tstw %2,0(%1)" \
"\n2:\tstw %R2,4(%1)\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\
ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\
: "=r"(__pu_err) \
: "r"(ptr), "r"(__val), "0"(__pu_err) \
: "r1"); \
} while (0)
#define __put_user_asm64(__val,ptr) do { \
__asm__ __volatile__ ( \
"\n1:\tstw %2,0(%%sr3,%1)" \
"\n2:\tstw %R2,4(%%sr3,%1)\n\t" \
ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\
ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\
: "=r"(__pu_err) \
: "r"(ptr), "r"(__val), "0"(__pu_err) \
: "r1"); \
} while (0)
#endif /* !defined(CONFIG_64BIT) */
/*
* Complex access routines -- external declarations
*/
extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
extern long strncpy_from_user(char *, const char __user *, long);
extern unsigned lclear_user(void __user *,unsigned long);
extern long lstrnlen_user(const char __user *,long);
/*
* Complex access routines -- macros
*/
#ifdef CONFIG_COMPAT
#define user_addr_max() (TASK_SIZE)
#else
#define user_addr_max() (DEFAULT_TASK_SIZE)
#endif
#define strnlen_user lstrnlen_user
#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
#define clear_user lclear_user
#define __clear_user lclear_user
unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len);
#define __copy_to_user copy_to_user
unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len);
unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len);
#define __copy_in_user copy_in_user
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
extern void copy_from_user_overflow(void)
#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
__compiletime_error("copy_from_user() buffer size is not provably correct")
#else
__compiletime_warning("copy_from_user() buffer size is not provably correct")
#endif
;
static inline unsigned long __must_check copy_from_user(void *to,
const void __user *from,
unsigned long n)
{
int sz = __compiletime_object_size(to);
int ret = -EFAULT;
if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n))
ret = __copy_from_user(to, from, n);
else
copy_from_user_overflow();
return ret;
}
struct pt_regs;
int fixup_exception(struct pt_regs *regs);
#endif /* __PARISC_UACCESS_H */
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