Commit 4c512485 authored by Matthew Wilcox's avatar Matthew Wilcox Committed by Linus Torvalds

x86: implement memset16, memset32 & memset64

These are single instructions on x86.  There's no 64-bit instruction for
x86-32, but we don't yet have any user for memset64() on 32-bit
architectures, so don't bother to implement it.

Link: http://lkml.kernel.org/r/20170720184539.31609-4-willy@infradead.orgSigned-off-by: default avatarMatthew Wilcox <mawilcox@microsoft.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: David Miller <davem@davemloft.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 03270c13
...@@ -340,6 +340,30 @@ extern void *memset(void *, int, size_t); ...@@ -340,6 +340,30 @@ extern void *memset(void *, int, size_t);
#endif #endif
#endif /* !CONFIG_FORTIFY_SOURCE */ #endif /* !CONFIG_FORTIFY_SOURCE */
#define __HAVE_ARCH_MEMSET16
static inline void *memset16(uint16_t *s, uint16_t v, size_t n)
{
int d0, d1;
asm volatile("rep\n\t"
"stosw"
: "=&c" (d0), "=&D" (d1)
: "a" (v), "1" (s), "0" (n)
: "memory");
return s;
}
#define __HAVE_ARCH_MEMSET32
static inline void *memset32(uint32_t *s, uint32_t v, size_t n)
{
int d0, d1;
asm volatile("rep\n\t"
"stosl"
: "=&c" (d0), "=&D" (d1)
: "a" (v), "1" (s), "0" (n)
: "memory");
return s;
}
/* /*
* find the first occurrence of byte 'c', or 1 past the area if none * find the first occurrence of byte 'c', or 1 past the area if none
*/ */
......
...@@ -58,6 +58,42 @@ extern void *__memcpy(void *to, const void *from, size_t len); ...@@ -58,6 +58,42 @@ extern void *__memcpy(void *to, const void *from, size_t len);
void *memset(void *s, int c, size_t n); void *memset(void *s, int c, size_t n);
void *__memset(void *s, int c, size_t n); void *__memset(void *s, int c, size_t n);
#define __HAVE_ARCH_MEMSET16
static inline void *memset16(uint16_t *s, uint16_t v, size_t n)
{
long d0, d1;
asm volatile("rep\n\t"
"stosw"
: "=&c" (d0), "=&D" (d1)
: "a" (v), "1" (s), "0" (n)
: "memory");
return s;
}
#define __HAVE_ARCH_MEMSET32
static inline void *memset32(uint32_t *s, uint32_t v, size_t n)
{
long d0, d1;
asm volatile("rep\n\t"
"stosl"
: "=&c" (d0), "=&D" (d1)
: "a" (v), "1" (s), "0" (n)
: "memory");
return s;
}
#define __HAVE_ARCH_MEMSET64
static inline void *memset64(uint64_t *s, uint64_t v, size_t n)
{
long d0, d1;
asm volatile("rep\n\t"
"stosq"
: "=&c" (d0), "=&D" (d1)
: "a" (v), "1" (s), "0" (n)
: "memory");
return s;
}
#define __HAVE_ARCH_MEMMOVE #define __HAVE_ARCH_MEMMOVE
void *memmove(void *dest, const void *src, size_t count); void *memmove(void *dest, const void *src, size_t count);
void *__memmove(void *dest, const void *src, size_t count); void *__memmove(void *dest, const void *src, size_t count);
......
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