WSL2-Linux-Kernel/sound/core/memory.c

88 строки
2.4 KiB
C
Исходник Обычный вид История

/*
* Copyright (c) by Jaroslav Kysela <perex@suse.cz>
*
* Misc memory accessors
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/config.h>
#include <asm/io.h>
#include <asm/uaccess.h>
/**
* copy_to_user_fromio - copy data from mmio-space to user-space
* @dst: the destination pointer on user-space
* @src: the source pointer on mmio
* @count: the data size to copy in bytes
*
* Copies the data from mmio-space to user-space.
*
* Returns zero if successful, or non-zero on failure.
*/
int copy_to_user_fromio(void __user *dst, const volatile void __iomem *src, size_t count)
{
#if defined(__i386__) || defined(CONFIG_SPARC32)
return copy_to_user(dst, (const void __force*)src, count) ? -EFAULT : 0;
#else
char buf[256];
while (count) {
size_t c = count;
if (c > sizeof(buf))
c = sizeof(buf);
memcpy_fromio(buf, (void __iomem *)src, c);
if (copy_to_user(dst, buf, c))
return -EFAULT;
count -= c;
dst += c;
src += c;
}
return 0;
#endif
}
/**
* copy_from_user_toio - copy data from user-space to mmio-space
* @dst: the destination pointer on mmio-space
* @src: the source pointer on user-space
* @count: the data size to copy in bytes
*
* Copies the data from user-space to mmio-space.
*
* Returns zero if successful, or non-zero on failure.
*/
int copy_from_user_toio(volatile void __iomem *dst, const void __user *src, size_t count)
{
#if defined(__i386__) || defined(CONFIG_SPARC32)
return copy_from_user((void __force *)dst, src, count) ? -EFAULT : 0;
#else
char buf[256];
while (count) {
size_t c = count;
if (c > sizeof(buf))
c = sizeof(buf);
if (copy_from_user(buf, src, c))
return -EFAULT;
memcpy_toio(dst, buf, c);
count -= c;
dst += c;
src += c;
}
return 0;
#endif
}