1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef _LINUX_VHOST_H
3#define _LINUX_VHOST_H
4/* Userspace interface for in-kernel virtio accelerators. */
5
6/* vhost is used to reduce the number of system calls involved in virtio.
7 *
8 * Existing virtio net code is used in the guest without modification.
9 *
10 * This header includes interface used by userspace hypervisor for
11 * device configuration.
12 */
13
14#include <linux/vhost_types.h>
15#include <linux/types.h>
16#include <linux/ioctl.h>
17
18/* ioctls */
19
20#define VHOST_VIRTIO 0xAF
21
22/* Features bitmask for forward compatibility. Transport bits are used for
23 * vhost specific features. */
24#define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u64)
25#define VHOST_SET_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u64)
26
27/* Set current process as the (exclusive) owner of this file descriptor. This
28 * must be called before any other vhost command. Further calls to
29 * VHOST_OWNER_SET fail until VHOST_OWNER_RESET is called. */
30#define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01)
31/* Give up ownership, and reset the device to default values.
32 * Allows subsequent call to VHOST_OWNER_SET to succeed. */
33#define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02)
34
35/* Set up/modify memory layout */
36#define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory)
37
38/* Write logging setup. */
39/* Memory writes can optionally be logged by setting bit at an offset
40 * (calculated from the physical address) from specified log base.
41 * The bit is set using an atomic 32 bit operation. */
42/* Set base address for logging. */
43#define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64)
44/* Specify an eventfd file descriptor to signal on log write. */
45#define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int)
46
47/* Ring setup. */
48/* Set number of descriptors in ring. This parameter can not
49 * be modified while ring is running (bound to a device). */
50#define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state)
51/* Set addresses for the ring. */
52#define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr)
53/* Base value where queue looks for available descriptors */
54#define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
55/* Get accessor: reads index, writes value in num */
56#define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
57
58/* Set the vring byte order in num. Valid values are VHOST_VRING_LITTLE_ENDIAN
59 * or VHOST_VRING_BIG_ENDIAN (other values return -EINVAL).
60 * The byte order cannot be changed while the device is active: trying to do so
61 * returns -EBUSY.
62 * This is a legacy only API that is simply ignored when VIRTIO_F_VERSION_1 is
63 * set.
64 * Not all kernel configurations support this ioctl, but all configurations that
65 * support SET also support GET.
66 */
67#define VHOST_VRING_LITTLE_ENDIAN 0
68#define VHOST_VRING_BIG_ENDIAN 1
69#define VHOST_SET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_state)
70#define VHOST_GET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state)
71
72/* The following ioctls use eventfd file descriptors to signal and poll
73 * for events. */
74
75/* Set eventfd to poll for added buffers */
76#define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file)
77/* Set eventfd to signal when buffers have beed used */
78#define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file)
79/* Set eventfd to signal an error */
80#define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
81/* Set busy loop timeout (in us) */
82#define VHOST_SET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x23, \
83 struct vhost_vring_state)
84/* Get busy loop timeout (in us) */
85#define VHOST_GET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x24, \
86 struct vhost_vring_state)
87
88/* Set or get vhost backend capability */
89
90/* Use message type V2 */
91#define VHOST_BACKEND_F_IOTLB_MSG_V2 0x1
92
93#define VHOST_SET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x25, __u64)
94#define VHOST_GET_BACKEND_FEATURES _IOR(VHOST_VIRTIO, 0x26, __u64)
95
96/* VHOST_NET specific defines */
97
98/* Attach virtio net ring to a raw socket, or tap device.
99 * The socket must be already bound to an ethernet device, this device will be
100 * used for transmit. Pass fd -1 to unbind from the socket and the transmit
101 * device. This can be used to stop the ring (e.g. for migration). */
102#define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file)
103
104/* VHOST_SCSI specific defines */
105
106#define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target)
107#define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target)
108/* Changing this breaks userspace. */
109#define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int)
110/* Set and get the events missed flag */
111#define VHOST_SCSI_SET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x43, __u32)
112#define VHOST_SCSI_GET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x44, __u32)
113
114/* VHOST_VSOCK specific defines */
115
116#define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u64)
117#define VHOST_VSOCK_SET_RUNNING _IOW(VHOST_VIRTIO, 0x61, int)
118
119#endif
120