1 #ifndef _UAPI_LINUX_VIRTIO_RING_H 2 #define _UAPI_LINUX_VIRTIO_RING_H 3 /* An interface for efficient virtio implementation, currently for use by KVM 4 * and lguest, but hopefully others soon. Do NOT change this since it will 5 * break existing servers and clients. 6 * 7 * This header is BSD licensed so anyone can use the definitions to implement 8 * compatible drivers/servers. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of IBM nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Copyright Rusty Russell IBM Corporation 2007. */ 34 35 #include "linux/types.h" 36 #include "linux/virtio_types.h" 37 38 /* We support indirect buffer descriptors */ 39 #define VIRTIO_RING_F_INDIRECT_DESC 28 40 41 /* The Guest publishes the used index for which it expects an interrupt 42 * at the end of the avail ring. Host should ignore the avail->flags field. */ 43 /* The Host publishes the avail index for which it expects a kick 44 * at the end of the used ring. Guest should ignore the used->flags field. */ 45 #define VIRTIO_RING_F_EVENT_IDX 29 46 47 void vring_transport_features(VirtIODevice *vdev, u64 *features); 48 unsigned long vring_size(unsigned int num, unsigned long align, bool packed); 49 50 #endif /* _UAPI_LINUX_VIRTIO_RING_H */ 51