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#ifndef __PARISC_UACCESS_H
#define __PARISC_UACCESS_H
/*
* User space memory access functions
*/
#include <linux/sched.h>
#include <asm/page.h>
#include <asm/system.h>
#include <asm/cache.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->addr_limit)
#define set_fs(x) (current->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() or verify_area().
* We just let the page fault handler do the right thing. This also means
* that put_user is the same as __put_user, etc.
*/
#define access_ok(type,addr,size) (1)
#define verify_area(type,addr,size) (0)
#define put_user __put_user
#define get_user __get_user
/*
* The exception table contains two values: the first is an address
* for an instruction that is allowed to fault, and the second is
* the number of bytes to skip if a fault occurs. We also support in
* two bit flags: 0x2 tells the exception handler to clear register
* r9 and 0x1 tells the exception handler to put -EFAULT in r8.
* This allows us to handle the simple cases for put_user and
* get_user without having to have .fixup sections.
*/
struct exception_table_entry {
unsigned long addr; /* address of insn that is allowed to fault. */
int skip; /* pcoq skip | r9 clear flag | r8 -EFAULT flag */
};
extern const struct exception_table_entry
*search_exception_table(unsigned long 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: __get_kernel_asm("ldd",ptr); break; \
default: BUG(); 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: __get_user_asm("ldd",ptr); break; \
default: BUG(); break; \
} \
} \
\
(x) = (__typeof__(*(ptr))) __gu_val; \
__gu_err; \
})
#define __get_kernel_asm(ldx,ptr) \
__asm__("\n1:\t" ldx "\t0(%2),%0\n" \
"2:\n" \
"\t.section __ex_table,\"a\"\n" \
"\t.word\t1b\n" \
"\t.word\t(2b-1b)+3\n" \
"\t.previous" \
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err));
#define __get_user_asm(ldx,ptr) \
__asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n" \
"2:\n" \
"\t.section __ex_table,\"a\"\n" \
"\t.word\t1b\n" \
"\t.word\t(2b-1b)+3\n" \
"\t.previous" \
: "=r"(__gu_val), "=r"(__gu_err) \
: "r"(ptr), "1"(__gu_err));
#define __put_user(x,ptr) \
({ \
register long __pu_err __asm__ ("r8") = 0; \
\
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: __put_kernel_asm("std",x,ptr); break; \
default: BUG(); 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: __put_user_asm("std",x,ptr); break; \
default: BUG(); 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.
*/
#define __put_kernel_asm(stx,x,ptr) \
__asm__ __volatile__ ( \
"\n1:\t" stx "\t%2,0(%1)\n" \
"2:\n" \
"\t.section __ex_table,\"a\"\n" \
"\t.word\t1b\n" \
"\t.word\t(2b-1b)+1\n" \
"\t.previous" \
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err))
#define __put_user_asm(stx,x,ptr) \
__asm__ __volatile__ ( \
"\n1:\t" stx "\t%2,0(%%sr3,%1)\n" \
"2:\n" \
"\t.section __ex_table,\"a\"\n" \
"\t.word\t1b\n" \
"\t.word\t(2b-1b)+1\n" \
"\t.previous" \
: "=r"(__pu_err) \
: "r"(ptr), "r"(x), "0"(__pu_err))
/*
* Complex access routines -- external declarations
*/
extern unsigned long lcopy_to_user(void *, const void *, unsigned long);
extern unsigned long lcopy_from_user(void *, const void *, unsigned long);
extern long lstrncpy_from_user(char *, const char *, long);
extern unsigned lclear_user(void *,unsigned long);
extern long lstrnlen_user(const char *,long);
/*
* Complex access routines -- macros
*/
#define strncpy_from_user lstrncpy_from_user
#define strnlen_user lstrnlen_user
#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
#define clear_user lclear_user
#define copy_from_user lcopy_from_user
#define __copy_from_user lcopy_from_user
#define copy_to_user lcopy_to_user
#define __copy_to_user lcopy_to_user
#define copy_to_user_ret(to,from,n,retval) \
({ if (lcopy_to_user(to,from,n)) return retval; })
#define copy_from_user_ret(to,from,n,retval) \
({ if (lcopy_from_user(to,from,n)) return retval; })
#endif /* __PARISC_UACCESS_H */
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