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Linux kernel mirror (for testing)
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linux
1/*
2 * Virtio PCI driver
3 *
4 * This module allows virtio devices to be used over a virtual PCI device.
5 * This can be used with QEMU based VMMs like KVM or Xen.
6 *
7 * Copyright IBM Corp. 2007
8 *
9 * Authors:
10 * Anthony Liguori <aliguori@us.ibm.com>
11 *
12 * This header is BSD licensed so anyone can use the definitions to implement
13 * compatible drivers/servers.
14 */
15
16#ifndef _LINUX_VIRTIO_PCI_H
17#define _LINUX_VIRTIO_PCI_H
18
19#include <linux/virtio_config.h>
20
21/* A 32-bit r/o bitmask of the features supported by the host */
22#define VIRTIO_PCI_HOST_FEATURES 0
23
24/* A 32-bit r/w bitmask of features activated by the guest */
25#define VIRTIO_PCI_GUEST_FEATURES 4
26
27/* A 32-bit r/w PFN for the currently selected queue */
28#define VIRTIO_PCI_QUEUE_PFN 8
29
30/* A 16-bit r/o queue size for the currently selected queue */
31#define VIRTIO_PCI_QUEUE_NUM 12
32
33/* A 16-bit r/w queue selector */
34#define VIRTIO_PCI_QUEUE_SEL 14
35
36/* A 16-bit r/w queue notifier */
37#define VIRTIO_PCI_QUEUE_NOTIFY 16
38
39/* An 8-bit device status register. */
40#define VIRTIO_PCI_STATUS 18
41
42/* An 8-bit r/o interrupt status register. Reading the value will return the
43 * current contents of the ISR and will also clear it. This is effectively
44 * a read-and-acknowledge. */
45#define VIRTIO_PCI_ISR 19
46
47/* The bit of the ISR which indicates a device configuration change. */
48#define VIRTIO_PCI_ISR_CONFIG 0x2
49
50/* The remaining space is defined by each driver as the per-driver
51 * configuration space */
52#define VIRTIO_PCI_CONFIG 20
53
54/* Virtio ABI version, this must match exactly */
55#define VIRTIO_PCI_ABI_VERSION 0
56
57/* How many bits to shift physical queue address written to QUEUE_PFN.
58 * 12 is historical, and due to x86 page size. */
59#define VIRTIO_PCI_QUEUE_ADDR_SHIFT 12
60
61/* The alignment to use between consumer and producer parts of vring.
62 * x86 pagesize again. */
63#define VIRTIO_PCI_VRING_ALIGN 4096
64#endif