linux/arch/x86/kernel/x8664_ksyms_64.c
Tony Luck 92b0729c34 x86/mm, x86/mce: Add memcpy_mcsafe()
Make use of the EXTABLE_FAULT exception table entries to write
a kernel copy routine that doesn't crash the system if it
encounters a machine check. Prime use case for this is to copy
from large arrays of non-volatile memory used as storage.

We have to use an unrolled copy loop for now because current
hardware implementations treat a machine check in "rep mov"
as fatal. When that is fixed we can simplify.

Return type is a "bool". True means that we copied OK, false means
that it didn't.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@gmail.com>
Link: http://lkml.kernel.org/r/a44e1055efc2d2a9473307b22c91caa437aa3f8b.1456439214.git.tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-08 17:54:38 +01:00

82 lines
2.0 KiB
C

/* Exports for assembly files.
All C exports should go in the respective C files. */
#include <linux/module.h>
#include <linux/smp.h>
#include <net/checksum.h>
#include <asm/processor.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>
#include <asm/desc.h>
#include <asm/ftrace.h>
#ifdef CONFIG_FUNCTION_TRACER
/* mcount and __fentry__ are defined in assembly */
#ifdef CC_USING_FENTRY
EXPORT_SYMBOL(__fentry__);
#else
EXPORT_SYMBOL(mcount);
#endif
#endif
EXPORT_SYMBOL(__get_user_1);
EXPORT_SYMBOL(__get_user_2);
EXPORT_SYMBOL(__get_user_4);
EXPORT_SYMBOL(__get_user_8);
EXPORT_SYMBOL(__put_user_1);
EXPORT_SYMBOL(__put_user_2);
EXPORT_SYMBOL(__put_user_4);
EXPORT_SYMBOL(__put_user_8);
EXPORT_SYMBOL(copy_user_generic_string);
EXPORT_SYMBOL(copy_user_generic_unrolled);
EXPORT_SYMBOL(copy_user_enhanced_fast_string);
EXPORT_SYMBOL(__copy_user_nocache);
EXPORT_SYMBOL(_copy_from_user);
EXPORT_SYMBOL(_copy_to_user);
EXPORT_SYMBOL_GPL(memcpy_mcsafe);
EXPORT_SYMBOL(copy_page);
EXPORT_SYMBOL(clear_page);
EXPORT_SYMBOL(csum_partial);
/*
* Export string functions. We normally rely on gcc builtin for most of these,
* but gcc sometimes decides not to inline them.
*/
#undef memcpy
#undef memset
#undef memmove
extern void *__memset(void *, int, __kernel_size_t);
extern void *__memcpy(void *, const void *, __kernel_size_t);
extern void *__memmove(void *, const void *, __kernel_size_t);
extern void *memset(void *, int, __kernel_size_t);
extern void *memcpy(void *, const void *, __kernel_size_t);
extern void *memmove(void *, const void *, __kernel_size_t);
EXPORT_SYMBOL(__memset);
EXPORT_SYMBOL(__memcpy);
EXPORT_SYMBOL(__memmove);
EXPORT_SYMBOL(memset);
EXPORT_SYMBOL(memcpy);
EXPORT_SYMBOL(memmove);
#ifndef CONFIG_DEBUG_VIRTUAL
EXPORT_SYMBOL(phys_base);
#endif
EXPORT_SYMBOL(empty_zero_page);
#ifndef CONFIG_PARAVIRT
EXPORT_SYMBOL(native_load_gs_index);
#endif
#ifdef CONFIG_PREEMPT
EXPORT_SYMBOL(___preempt_schedule);
EXPORT_SYMBOL(___preempt_schedule_notrace);
#endif