virtqueue.h revision 227652 
1/*-
2 * Copyright (c) 2011, Bryan Venteicher <bryanv@daemoninthecloset.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice unmodified, this list of conditions, and the following
10 *    disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/dev/virtio/virtqueue.h 227652 2011-11-18 05:43:43Z grehan $
27 */
28
29#ifndef _VIRTIO_VIRTQUEUE_H
30#define _VIRTIO_VIRTQUEUE_H
31
32#include <sys/types.h>
33
34struct virtqueue;
35struct sglist;
36
37/* Support for indirect buffer descriptors. */
38#define VIRTIO_RING_F_INDIRECT_DESC	(1 << 28)
39
40/* The guest publishes the used index for which it expects an interrupt
41 * at the end of the avail ring. Host should ignore the avail->flags field.
42 * The host publishes the avail index for which it expects a kick
43 * at the end of the used ring. Guest should ignore the used->flags field.
44 */
45#define VIRTIO_RING_F_EVENT_IDX		(1 << 29)
46
47/* Device callback for a virtqueue interrupt. */
48typedef int virtqueue_intr_t(void *);
49
50#define VIRTQUEUE_MAX_NAME_SZ	32
51
52/* One for each virtqueue the device wishes to allocate. */
53struct vq_alloc_info {
54	char		   vqai_name[VIRTQUEUE_MAX_NAME_SZ];
55	int		   vqai_maxindirsz;
56	virtqueue_intr_t  *vqai_intr;
57	void		  *vqai_intr_arg;
58	struct virtqueue **vqai_vq;
59};
60
61#define VQ_ALLOC_INFO_INIT(_i,_nsegs,_intr,_arg,_vqp,_str,...) do {	\
62	snprintf((_i)->vqai_name, VIRTQUEUE_MAX_NAME_SZ, _str,		\
63	    ##__VA_ARGS__);						\
64	(_i)->vqai_maxindirsz = (_nsegs);				\
65	(_i)->vqai_intr = (_intr);					\
66	(_i)->vqai_intr_arg = (_arg);					\
67	(_i)->vqai_vq = (_vqp);						\
68} while (0)
69
70uint64_t virtqueue_filter_features(uint64_t features);
71
72int	 virtqueue_alloc(device_t dev, uint16_t queue, uint16_t size,
73	     int align, vm_paddr_t highaddr, struct vq_alloc_info *info,
74	     struct virtqueue **vqp);
75void	*virtqueue_drain(struct virtqueue *vq, int *last);
76void	 virtqueue_free(struct virtqueue *vq);
77int	 virtqueue_reinit(struct virtqueue *vq, uint16_t size);
78
79int	 virtqueue_intr(struct virtqueue *vq);
80int	 virtqueue_enable_intr(struct virtqueue *vq);
81void	 virtqueue_disable_intr(struct virtqueue *vq);
82
83/* Get physical address of the virtqueue ring. */
84vm_paddr_t virtqueue_paddr(struct virtqueue *vq);
85
86int	 virtqueue_full(struct virtqueue *vq);
87int	 virtqueue_empty(struct virtqueue *vq);
88int	 virtqueue_size(struct virtqueue *vq);
89int	 virtqueue_nused(struct virtqueue *vq);
90void	 virtqueue_notify(struct virtqueue *vq);
91void	 virtqueue_dump(struct virtqueue *vq);
92
93int	 virtqueue_enqueue(struct virtqueue *vq, void *cookie,
94	     struct sglist *sg, int readable, int writable);
95void	*virtqueue_dequeue(struct virtqueue *vq, uint32_t *len);
96void	*virtqueue_poll(struct virtqueue *vq, uint32_t *len);
97
98#endif /* _VIRTIO_VIRTQUEUE_H */
99