freebsd-dev/sys/dev/virtio/virtio_endian.h
Ka Ho Ng 54ac6f721e bhyve: virtio shares definitions between sys/dev/virtio
Definitions inside usr.sbin/bhyve/virtio.h are thrown away.
Definitions in sys/dev/virtio are used instead.

This reduces code duplication.

Sponsored by:	The FreeBSD Foundation
Reviewed by:	grehan
Approved by:	philip (mentor)
Differential Revision:	https://reviews.freebsd.org/D29084
2021-03-16 19:29:39 +08:00

110 lines
2.8 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2017, Bryan Venteicher <bryanv@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _VIRTIO_ENDIAN_H_
#define _VIRTIO_ENDIAN_H_
#include <sys/endian.h>
#ifndef _KERNEL
#include <stdbool.h>
#endif /* _KERNEL */
/*
* VirtIO V1 (modern) uses little endian, while legacy VirtIO uses the guest's
* native endian. These functions convert to and from the Guest's (driver's)
* and the Host's (device's) endianness when needed.
*/
static inline bool
virtio_swap_endian(bool modern)
{
#if _BYTE_ORDER == _LITTLE_ENDIAN
return (false);
#else
return (modern);
#endif
}
static inline uint16_t
virtio_htog16(bool modern, uint16_t val)
{
if (virtio_swap_endian(modern))
return (le16toh(val));
else
return (val);
}
static inline uint16_t
virtio_gtoh16(bool modern, uint16_t val)
{
if (virtio_swap_endian(modern))
return (htole16(val));
else
return (val);
}
static inline uint32_t
virtio_htog32(bool modern, uint32_t val)
{
if (virtio_swap_endian(modern))
return (le32toh(val));
else
return (val);
}
static inline uint32_t
virtio_gtoh32(bool modern, uint32_t val)
{
if (virtio_swap_endian(modern))
return (htole32(val));
else
return (val);
}
static inline uint64_t
virtio_htog64(bool modern, uint64_t val)
{
if (virtio_swap_endian(modern))
return (le64toh(val));
else
return (val);
}
static inline uint64_t
virtio_gtoh64(bool modern, uint64_t val)
{
if (virtio_swap_endian(modern))
return (htole64(val));
else
return (val);
}
#endif /* _VIRTIO_ENDIAN_H_ */