/*************************************************************************/ /*!
@File
@Title          Utility functions for user space access
@Copyright      Copyright (c) Imagination Technologies Ltd. All Rights Reserved
@License        Dual MIT/GPLv2

The contents of this file are subject to the MIT license as set out below.

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of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
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The above copyright notice and this permission notice shall be included in
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the GNU General Public License Version 2 ("GPL") in which case the provisions
of GPL are applicable instead of those above.

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not delete the provisions above, a recipient may use your version of this file
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"MIT-COPYING".

EXCEPT AS OTHERWISE STATED IN A NEGOTIATED AGREEMENT: (A) THE SOFTWARE IS
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*/ /**************************************************************************/
#ifndef __PVR_UACCESS_H__
#define __PVR_UACCESS_H__

#include <linux/uaccess.h>
#include <linux/version.h>

static inline unsigned long pvr_copy_to_user(void __user *pvTo, const void *pvFrom, unsigned long ulBytes)
{
#if (LINUX_VERSION_CODE < KERNEL_VERSION(5, 0, 0))
	if (access_ok(VERIFY_WRITE, pvTo, ulBytes))
#else
	if (access_ok(pvTo, ulBytes))
#endif
	{
		return __copy_to_user(pvTo, pvFrom, ulBytes);
	}

	return ulBytes;
}


#if defined(__KLOCWORK__)
	/* this part is only to tell Klocwork not to report false positive because
	   it doesn't understand that pvr_copy_from_user will initialise the memory
	   pointed to by pvTo */
#include <linux/string.h> /* get the memset prototype */
static inline unsigned long pvr_copy_from_user(void *pvTo, const void __user *pvFrom, unsigned long ulBytes)
{
	if (pvTo != NULL)
	{
		memset(pvTo, 0xAA, ulBytes);
		return 0;
	}
	return 1;
}

#else /* real implementation */

static inline unsigned long pvr_copy_from_user(void *pvTo, const void __user *pvFrom, unsigned long ulBytes)
{
	/*
	 * The compile time correctness checking introduced for copy_from_user in
	 * Linux 2.6.33 isn't fully compatible with our usage of the function.
	 */
#if (LINUX_VERSION_CODE < KERNEL_VERSION(5, 0, 0))
	if (access_ok(VERIFY_READ, pvFrom, ulBytes))
#else
	if (access_ok(pvFrom, ulBytes))
#endif
	{
		return __copy_from_user(pvTo, pvFrom, ulBytes);
	}

	return ulBytes;
}
#endif /* klocworks */

#endif /* __PVR_UACCESS_H__ */