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author | Michael S. Tsirkin | 2014-10-22 14:35:56 +0200 |
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committer | Michael S. Tsirkin | 2014-12-09 11:05:24 +0100 |
commit | eef960a04354d13426c43a4e3750a5e2b383040c (patch) | |
tree | a5d6e327dbb22c85b2f6592077a544bcc0153471 /include/uapi/linux/virtio_types.h | |
parent | virtio: add virtio 1.0 feature bit (diff) | |
download | kernel-qcow2-linux-eef960a04354d13426c43a4e3750a5e2b383040c.tar.gz kernel-qcow2-linux-eef960a04354d13426c43a4e3750a5e2b383040c.tar.xz kernel-qcow2-linux-eef960a04354d13426c43a4e3750a5e2b383040c.zip |
virtio: memory access APIs
virtio 1.0 makes all memory structures LE, so
we need APIs to conditionally do a byteswap on BE
architectures.
To make it easier to check code statically,
add virtio specific types for multi-byte integers
in memory.
Add low level wrappers that do a byteswap conditionally, these will be
useful e.g. for vhost. Add high level wrappers that
query device endian-ness and act accordingly.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Diffstat (limited to 'include/uapi/linux/virtio_types.h')
-rw-r--r-- | include/uapi/linux/virtio_types.h | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/include/uapi/linux/virtio_types.h b/include/uapi/linux/virtio_types.h new file mode 100644 index 000000000000..e845e8c4cbee --- /dev/null +++ b/include/uapi/linux/virtio_types.h @@ -0,0 +1,46 @@ +#ifndef _UAPI_LINUX_VIRTIO_TYPES_H +#define _UAPI_LINUX_VIRTIO_TYPES_H +/* Type definitions for virtio implementations. + * + * This header is BSD licensed so anyone can use the definitions to implement + * compatible drivers/servers. + * + * 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, 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. + * 3. Neither the name of IBM nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``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 IBM OR CONTRIBUTORS 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. + * + * Copyright (C) 2014 Red Hat, Inc. + * Author: Michael S. Tsirkin <mst@redhat.com> + */ +#include <linux/types.h> + +/* + * __virtio{16,32,64} have the following meaning: + * - __u{16,32,64} for virtio devices in legacy mode, accessed in native endian + * - __le{16,32,64} for standard-compliant virtio devices + */ + +typedef __u16 __bitwise__ __virtio16; +typedef __u32 __bitwise__ __virtio32; +typedef __u64 __bitwise__ __virtio64; + +#endif /* _UAPI_LINUX_VIRTIO_TYPES_H */ |