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/*
* User address space access functions.
*
* For licencing details see kernel-base/COPYING
*/
#include <linux/uaccess.h>
#include <linux/export.h>
#include <asm/tlbflush.h>
/*
* We rely on the nested NMI work to allow atomic faults from the NMI path; the
* nested NMI paths are careful to preserve CR2.
*/
unsigned long
copy_from_user_nmi(void *to, const void __user *from, unsigned long n)
{
unsigned long ret;
if (__range_not_ok(from, n, TASK_SIZE))
return n;
if (!nmi_uaccess_okay())
return n;
/*
* Even though this function is typically called from NMI/IRQ context
* disable pagefaults so that its behaviour is consistent even when
* called form other contexts.
*/
pagefault_disable();
ret = __copy_from_user_inatomic(to, from, n);
pagefault_enable();
return ret;
}
EXPORT_SYMBOL_GPL(copy_from_user_nmi);
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