linux/sound/core/memory.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) by Jaroslav Kysela <perex@perex.cz>
*
* Misc memory accessors
*/
#include <linux/export.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <sound/core.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.
*
* Return: 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
}
EXPORT_SYMBOL(copy_to_user_fromio);
/**
* 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.
*
* Return: 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
}
EXPORT_SYMBOL(copy_from_user_toio);