hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

mn10300: get rid of zeroing 

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2017-03-20 20:45:41 -04:00
parent 6c03905a63
commit 4df3715efe
2 changed files with 21 additions and 142 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

152
arch/mn10300/include/asm/uaccess.h
View File

@ -275,55 +275,19 @@ do { \
} \
} while (0)
#define __copy_user_zeroing(to, from, size) \
do { \
if (size) { \
void *__to = to; \
const void *__from = from; \
int w; \
asm volatile( \
"0: movbu (%0),%3;\n" \
"1: movbu %3,(%1);\n" \
" inc %0;\n" \
" inc %1;\n" \
" add -1,%2;\n" \
" bne 0b;\n" \
"2:\n" \
" .section .fixup,\"ax\"\n" \
"3:\n" \
" mov %2,%0\n" \
" clr %3\n" \
"4: movbu %3,(%1);\n" \
" inc %1;\n" \
" add -1,%2;\n" \
" bne 4b;\n" \
" mov %0,%2\n" \
" jmp 2b\n" \
" .previous\n" \
" .section __ex_table,\"a\"\n" \
" .balign 4\n" \
" .long 0b,3b\n" \
" .long 1b,3b\n" \
" .previous\n" \
: "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\
: "0"(__from), "1"(__to), "2"(size) \
: "cc", "memory"); \
} \
} while (0)
/* 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 *from,
unsigned long __copy_from_user_inatomic(void *to, const void __user *from,
unsigned long n)
{
__copy_user_zeroing(to, from, n);
__copy_user(to, from, n);
return n;
}
static inline
unsigned long __generic_copy_to_user_nocheck(void *to, const void *from,
unsigned long __copy_to_user_inatomic(void __user *to, const void *from,
unsigned long n)
{
__copy_user(to, from, n);
@ -331,110 +295,24 @@ unsigned long __generic_copy_to_user_nocheck(void *to, const void *from,
}
#if 0
#error "don't use - these macros don't increment to & from pointers"
/* Optimize just a little bit when we know the size of the move. */
#define __constant_copy_user(to, from, size) \
do { \
asm volatile( \
" mov %0,a0;\n" \
"0: movbu (%1),d3;\n" \
"1: movbu d3,(%2);\n" \
" add -1,a0;\n" \
" bne 0b;\n" \
"2:;" \
".section .fixup,\"ax\"\n" \
"3: jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .balign 4\n" \
" .long 0b,3b\n" \
" .long 1b,3b\n" \
".previous" \
: \
: "d"(size), "d"(to), "d"(from) \
: "d3", "a0"); \
} while (0)
/* Optimize just a little bit when we know the size of the move. */
#define __constant_copy_user_zeroing(to, from, size) \
do { \
asm volatile( \
" mov %0,a0;\n" \
"0: movbu (%1),d3;\n" \
"1: movbu d3,(%2);\n" \
" add -1,a0;\n" \
" bne 0b;\n" \
"2:;" \
".section .fixup,\"ax\"\n" \
"3: jmp 2b\n" \
".previous\n" \
".section __ex_table,\"a\"\n" \
" .balign 4\n" \
" .long 0b,3b\n" \
" .long 1b,3b\n" \
".previous" \
: \
: "d"(size), "d"(to), "d"(from) \
: "d3", "a0"); \
} while (0)
static inline
unsigned long __constant_copy_to_user(void *to, const void *from,
unsigned long n)
{
if (access_ok(VERIFY_WRITE, to, n))
__constant_copy_user(to, from, n);
return n;
}
static inline
unsigned long __constant_copy_from_user(void *to, const void *from,
unsigned long n)
{
if (access_ok(VERIFY_READ, from, n))
__constant_copy_user_zeroing(to, from, n);
return n;
}
static inline
unsigned long __constant_copy_to_user_nocheck(void *to, const void *from,
unsigned long n)
{
__constant_copy_user(to, from, n);
return n;
}
static inline
unsigned long __constant_copy_from_user_nocheck(void *to, const void *from,
unsigned long n)
{
__constant_copy_user_zeroing(to, from, n);
return n;
}
#endif
extern unsigned long __generic_copy_to_user(void __user *, const void *,
unsigned long);
extern unsigned long __generic_copy_from_user(void *, const void __user *,
unsigned long);
#define __copy_to_user_inatomic(to, from, n) \
__generic_copy_to_user_nocheck((to), (from), (n))
#define __copy_from_user_inatomic(to, from, n) \
__generic_copy_from_user_nocheck((to), (from), (n))
static inline unsigned long __copy_to_user(void __user *to, const void *from,
unsigned long n)
{
might_fault();
return __copy_to_user_inatomic(to, from, n);
}
#define __copy_to_user(to, from, n) \
({ \
might_fault(); \
__copy_to_user_inatomic((to), (from), (n)); \
})
#define __copy_from_user(to, from, n) \
({ \
might_fault(); \
__copy_from_user_inatomic((to), (from), (n)); \
})
static inline unsigned long __copy_from_user(void *to, const void __user *from,
unsigned long n)
{
might_fault();
return __copy_from_user_inatomic(to, from, n);
}
#define copy_to_user(to, from, n) __generic_copy_to_user((to), (from), (n))

11
arch/mn10300/lib/usercopy.c
View File

@ -22,11 +22,12 @@ __generic_copy_to_user(void *to, const void *from, unsigned long n)
unsigned long
__generic_copy_from_user(void *to, const void *from, unsigned long n)
{
if (access_ok(VERIFY_READ, from, n))
__copy_user_zeroing(to, from, n);
else
memset(to, 0, n);
return n;
unsigned long res = n;
if (access_ok(VERIFY_READ, from, res))
__copy_user(to, from, res);
if (unlikely(res))
memset(to + n - res, 0, res);
return res;
}
/*