linux_dsm_epyc7002/arch/parisc/lib/memcpy.c
Christoph Hellwig fe557319aa maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
Better describe what these functions do.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-17 10:57:41 -07:00

67 lines
1.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Optimized memory copy routines.
*
* Copyright (C) 2004 Randolph Chung <tausq@debian.org>
* Copyright (C) 2013-2017 Helge Deller <deller@gmx.de>
*
* Portions derived from the GNU C Library
* Copyright (C) 1991, 1997, 2003 Free Software Foundation, Inc.
*/
#include <linux/module.h>
#include <linux/compiler.h>
#include <linux/uaccess.h>
#define get_user_space() (uaccess_kernel() ? 0 : mfsp(3))
#define get_kernel_space() (0)
/* Returns 0 for success, otherwise, returns number of bytes not transferred. */
extern unsigned long pa_memcpy(void *dst, const void *src,
unsigned long len);
unsigned long raw_copy_to_user(void __user *dst, const void *src,
unsigned long len)
{
mtsp(get_kernel_space(), 1);
mtsp(get_user_space(), 2);
return pa_memcpy((void __force *)dst, src, len);
}
EXPORT_SYMBOL(raw_copy_to_user);
unsigned long raw_copy_from_user(void *dst, const void __user *src,
unsigned long len)
{
mtsp(get_user_space(), 1);
mtsp(get_kernel_space(), 2);
return pa_memcpy(dst, (void __force *)src, len);
}
EXPORT_SYMBOL(raw_copy_from_user);
unsigned long raw_copy_in_user(void __user *dst, const void __user *src, unsigned long len)
{
mtsp(get_user_space(), 1);
mtsp(get_user_space(), 2);
return pa_memcpy((void __force *)dst, (void __force *)src, len);
}
void * memcpy(void * dst,const void *src, size_t count)
{
mtsp(get_kernel_space(), 1);
mtsp(get_kernel_space(), 2);
pa_memcpy(dst, src, count);
return dst;
}
EXPORT_SYMBOL(raw_copy_in_user);
EXPORT_SYMBOL(memcpy);
bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
if ((unsigned long)unsafe_src < PAGE_SIZE)
return false;
/* check for I/O space F_EXTEND(0xfff00000) access as well? */
return true;
}