Linux kernel mirror (for testing)
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linux
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/types.h>
15#include <linux/compiler.h>
16#include <linux/ioctl.h>
17#include <linux/virtio_config.h>
18#include <linux/virtio_ring.h>
19
20struct vhost_vring_state {
21 unsigned int index;
22 unsigned int num;
23};
24
25struct vhost_vring_file {
26 unsigned int index;
27 int fd; /* Pass -1 to unbind from file. */
28
29};
30
31struct vhost_vring_addr {
32 unsigned int index;
33 /* Option flags. */
34 unsigned int flags;
35 /* Flag values: */
36 /* Whether log address is valid. If set enables logging. */
37#define VHOST_VRING_F_LOG 0
38
39 /* Start of array of descriptors (virtually contiguous) */
40 __u64 desc_user_addr;
41 /* Used structure address. Must be 32 bit aligned */
42 __u64 used_user_addr;
43 /* Available structure address. Must be 16 bit aligned */
44 __u64 avail_user_addr;
45 /* Logging support. */
46 /* Log writes to used structure, at offset calculated from specified
47 * address. Address must be 32 bit aligned. */
48 __u64 log_guest_addr;
49};
50
51/* no alignment requirement */
52struct vhost_iotlb_msg {
53 __u64 iova;
54 __u64 size;
55 __u64 uaddr;
56#define VHOST_ACCESS_RO 0x1
57#define VHOST_ACCESS_WO 0x2
58#define VHOST_ACCESS_RW 0x3
59 __u8 perm;
60#define VHOST_IOTLB_MISS 1
61#define VHOST_IOTLB_UPDATE 2
62#define VHOST_IOTLB_INVALIDATE 3
63#define VHOST_IOTLB_ACCESS_FAIL 4
64 __u8 type;
65};
66
67#define VHOST_IOTLB_MSG 0x1
68#define VHOST_IOTLB_MSG_V2 0x2
69
70struct vhost_msg {
71 int type;
72 union {
73 struct vhost_iotlb_msg iotlb;
74 __u8 padding[64];
75 };
76};
77
78struct vhost_msg_v2 {
79 __u32 type;
80 __u32 reserved;
81 union {
82 struct vhost_iotlb_msg iotlb;
83 __u8 padding[64];
84 };
85};
86
87struct vhost_memory_region {
88 __u64 guest_phys_addr;
89 __u64 memory_size; /* bytes */
90 __u64 userspace_addr;
91 __u64 flags_padding; /* No flags are currently specified. */
92};
93
94/* All region addresses and sizes must be 4K aligned. */
95#define VHOST_PAGE_SIZE 0x1000
96
97struct vhost_memory {
98 __u32 nregions;
99 __u32 padding;
100 struct vhost_memory_region regions[0];
101};
102
103/* ioctls */
104
105#define VHOST_VIRTIO 0xAF
106
107/* Features bitmask for forward compatibility. Transport bits are used for
108 * vhost specific features. */
109#define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u64)
110#define VHOST_SET_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u64)
111
112/* Set current process as the (exclusive) owner of this file descriptor. This
113 * must be called before any other vhost command. Further calls to
114 * VHOST_OWNER_SET fail until VHOST_OWNER_RESET is called. */
115#define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01)
116/* Give up ownership, and reset the device to default values.
117 * Allows subsequent call to VHOST_OWNER_SET to succeed. */
118#define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02)
119
120/* Set up/modify memory layout */
121#define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory)
122
123/* Write logging setup. */
124/* Memory writes can optionally be logged by setting bit at an offset
125 * (calculated from the physical address) from specified log base.
126 * The bit is set using an atomic 32 bit operation. */
127/* Set base address for logging. */
128#define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64)
129/* Specify an eventfd file descriptor to signal on log write. */
130#define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int)
131
132/* Ring setup. */
133/* Set number of descriptors in ring. This parameter can not
134 * be modified while ring is running (bound to a device). */
135#define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state)
136/* Set addresses for the ring. */
137#define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr)
138/* Base value where queue looks for available descriptors */
139#define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
140/* Get accessor: reads index, writes value in num */
141#define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
142
143/* Set the vring byte order in num. Valid values are VHOST_VRING_LITTLE_ENDIAN
144 * or VHOST_VRING_BIG_ENDIAN (other values return -EINVAL).
145 * The byte order cannot be changed while the device is active: trying to do so
146 * returns -EBUSY.
147 * This is a legacy only API that is simply ignored when VIRTIO_F_VERSION_1 is
148 * set.
149 * Not all kernel configurations support this ioctl, but all configurations that
150 * support SET also support GET.
151 */
152#define VHOST_VRING_LITTLE_ENDIAN 0
153#define VHOST_VRING_BIG_ENDIAN 1
154#define VHOST_SET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_state)
155#define VHOST_GET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state)
156
157/* The following ioctls use eventfd file descriptors to signal and poll
158 * for events. */
159
160/* Set eventfd to poll for added buffers */
161#define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file)
162/* Set eventfd to signal when buffers have beed used */
163#define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file)
164/* Set eventfd to signal an error */
165#define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
166/* Set busy loop timeout (in us) */
167#define VHOST_SET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x23, \
168 struct vhost_vring_state)
169/* Get busy loop timeout (in us) */
170#define VHOST_GET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x24, \
171 struct vhost_vring_state)
172
173/* Set or get vhost backend capability */
174
175/* Use message type V2 */
176#define VHOST_BACKEND_F_IOTLB_MSG_V2 0x1
177
178#define VHOST_SET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x25, __u64)
179#define VHOST_GET_BACKEND_FEATURES _IOR(VHOST_VIRTIO, 0x26, __u64)
180
181/* VHOST_NET specific defines */
182
183/* Attach virtio net ring to a raw socket, or tap device.
184 * The socket must be already bound to an ethernet device, this device will be
185 * used for transmit. Pass fd -1 to unbind from the socket and the transmit
186 * device. This can be used to stop the ring (e.g. for migration). */
187#define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file)
188
189/* Feature bits */
190/* Log all write descriptors. Can be changed while device is active. */
191#define VHOST_F_LOG_ALL 26
192/* vhost-net should add virtio_net_hdr for RX, and strip for TX packets. */
193#define VHOST_NET_F_VIRTIO_NET_HDR 27
194
195/* VHOST_SCSI specific definitions */
196
197/*
198 * Used by QEMU userspace to ensure a consistent vhost-scsi ABI.
199 *
200 * ABI Rev 0: July 2012 version starting point for v3.6-rc merge candidate +
201 * RFC-v2 vhost-scsi userspace. Add GET_ABI_VERSION ioctl usage
202 * ABI Rev 1: January 2013. Ignore vhost_tpgt filed in struct vhost_scsi_target.
203 * All the targets under vhost_wwpn can be seen and used by guset.
204 */
205
206#define VHOST_SCSI_ABI_VERSION 1
207
208struct vhost_scsi_target {
209 int abi_version;
210 char vhost_wwpn[224]; /* TRANSPORT_IQN_LEN */
211 unsigned short vhost_tpgt;
212 unsigned short reserved;
213};
214
215#define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target)
216#define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target)
217/* Changing this breaks userspace. */
218#define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int)
219/* Set and get the events missed flag */
220#define VHOST_SCSI_SET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x43, __u32)
221#define VHOST_SCSI_GET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x44, __u32)
222
223/* VHOST_VSOCK specific defines */
224
225#define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u64)
226#define VHOST_VSOCK_SET_RUNNING _IOW(VHOST_VIRTIO, 0x61, int)
227
228#endif