linux_dsm_epyc7002/arch/x86/include/asm/string_64.h
Dan Williams 6abccd1bfe x86, dax, pmem: remove indirection around memcpy_from_pmem()
memcpy_from_pmem() maps directly to memcpy_mcsafe(). The wrapper
serves no real benefit aside from affording a more generic function name
than the x86-specific 'mcsafe'. However this would not be the first time
that x86 terminology leaked into the global namespace. For lack of
better name, just use memcpy_mcsafe() directly.

This conversion also catches a place where we should have been using
plain memcpy, acpi_nfit_blk_single_io().

Cc: <x86@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:46 -07:00

115 lines
3.1 KiB
C

#ifndef _ASM_X86_STRING_64_H
#define _ASM_X86_STRING_64_H
#ifdef __KERNEL__
#include <linux/jump_label.h>
/* Written 2002 by Andi Kleen */
/* Only used for special circumstances. Stolen from i386/string.h */
static __always_inline void *__inline_memcpy(void *to, const void *from, size_t n)
{
unsigned long d0, d1, d2;
asm volatile("rep ; movsl\n\t"
"testb $2,%b4\n\t"
"je 1f\n\t"
"movsw\n"
"1:\ttestb $1,%b4\n\t"
"je 2f\n\t"
"movsb\n"
"2:"
: "=&c" (d0), "=&D" (d1), "=&S" (d2)
: "0" (n / 4), "q" (n), "1" ((long)to), "2" ((long)from)
: "memory");
return to;
}
/* Even with __builtin_ the compiler may decide to use the out of line
function. */
#define __HAVE_ARCH_MEMCPY 1
extern void *memcpy(void *to, const void *from, size_t len);
extern void *__memcpy(void *to, const void *from, size_t len);
#ifndef CONFIG_KMEMCHECK
#if (__GNUC__ == 4 && __GNUC_MINOR__ < 3) || __GNUC__ < 4
#define memcpy(dst, src, len) \
({ \
size_t __len = (len); \
void *__ret; \
if (__builtin_constant_p(len) && __len >= 64) \
__ret = __memcpy((dst), (src), __len); \
else \
__ret = __builtin_memcpy((dst), (src), __len); \
__ret; \
})
#endif
#else
/*
* kmemcheck becomes very happy if we use the REP instructions unconditionally,
* because it means that we know both memory operands in advance.
*/
#define memcpy(dst, src, len) __inline_memcpy((dst), (src), (len))
#endif
#define __HAVE_ARCH_MEMSET
void *memset(void *s, int c, size_t n);
void *__memset(void *s, int c, size_t n);
#define __HAVE_ARCH_MEMMOVE
void *memmove(void *dest, const void *src, size_t count);
void *__memmove(void *dest, const void *src, size_t count);
int memcmp(const void *cs, const void *ct, size_t count);
size_t strlen(const char *s);
char *strcpy(char *dest, const char *src);
char *strcat(char *dest, const char *src);
int strcmp(const char *cs, const char *ct);
#if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__)
/*
* For files that not instrumented (e.g. mm/slub.c) we
* should use not instrumented version of mem* functions.
*/
#undef memcpy
#define memcpy(dst, src, len) __memcpy(dst, src, len)
#define memmove(dst, src, len) __memmove(dst, src, len)
#define memset(s, c, n) __memset(s, c, n)
#endif
#define __HAVE_ARCH_MEMCPY_MCSAFE 1
__must_check int memcpy_mcsafe_unrolled(void *dst, const void *src, size_t cnt);
DECLARE_STATIC_KEY_FALSE(mcsafe_key);
/**
* memcpy_mcsafe - copy memory with indication if a machine check happened
*
* @dst: destination address
* @src: source address
* @cnt: number of bytes to copy
*
* Low level memory copy function that catches machine checks
* We only call into the "safe" function on systems that can
* actually do machine check recovery. Everyone else can just
* use memcpy().
*
* Return 0 for success, -EFAULT for fail
*/
static __always_inline __must_check int
memcpy_mcsafe(void *dst, const void *src, size_t cnt)
{
#ifdef CONFIG_X86_MCE
if (static_branch_unlikely(&mcsafe_key))
return memcpy_mcsafe_unrolled(dst, src, cnt);
else
#endif
memcpy(dst, src, cnt);
return 0;
}
#endif /* __KERNEL__ */
#endif /* _ASM_X86_STRING_64_H */