1 /*
2  * kvm_virtio.h - definition for virtio for kvm on s390
3  *
4  * Copyright IBM Corp. 2008
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License (version 2 only)
8  * as published by the Free Software Foundation.
9  *
10  *    Author(s): Christian Borntraeger <borntraeger@de.ibm.com>
11  */
12 
13 #ifndef __KVM_S390_VIRTIO_H
14 #define __KVM_S390_VIRTIO_H
15 
16 #include <linux/types.h>
17 
18 struct kvm_device_desc {
19 	/* The device type: console, network, disk etc.  Type 0 terminates. */
20 	__u8 type;
21 	/* The number of virtqueues (first in config array) */
22 	__u8 num_vq;
23 	/*
24 	 * The number of bytes of feature bits.  Multiply by 2: one for host
25 	 * features and one for guest acknowledgements.
26 	 */
27 	__u8 feature_len;
28 	/* The number of bytes of the config array after virtqueues. */
29 	__u8 config_len;
30 	/* A status byte, written by the Guest. */
31 	__u8 status;
32 	__u8 config[0];
33 };
34 
35 /*
36  * This is how we expect the device configuration field for a virtqueue
37  * to be laid out in config space.
38  */
39 struct kvm_vqconfig {
40 	/* The token returned with an interrupt. Set by the guest */
41 	__u64 token;
42 	/* The address of the virtio ring */
43 	__u64 address;
44 	/* The number of entries in the virtio_ring */
45 	__u16 num;
46 
47 };
48 
49 #define KVM_S390_VIRTIO_NOTIFY		0
50 #define KVM_S390_VIRTIO_RESET		1
51 #define KVM_S390_VIRTIO_SET_STATUS	2
52 
53 /* The alignment to use between consumer and producer parts of vring.
54  * This is pagesize for historical reasons. */
55 #define KVM_S390_VIRTIO_RING_ALIGN	4096
56 
57 
58 /* These values are supposed to be in ext_params on an interrupt */
59 #define VIRTIO_PARAM_MASK		0xff
60 #define VIRTIO_PARAM_VRING_INTERRUPT	0x0
61 #define VIRTIO_PARAM_CONFIG_CHANGED	0x1
62 #define VIRTIO_PARAM_DEV_ADD		0x2
63 
64 #endif
65