master
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#define VHOST_FILE_UNBIND -1
19
20/* ioctls */
21
22#define VHOST_VIRTIO 0xAF
23
24/* Features bitmask for forward compatibility. Transport bits are used for
25 * vhost specific features. */
26#define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u64)
27#define VHOST_SET_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u64)
28
29/* Set current process as the (exclusive) owner of this file descriptor. This
30 * must be called before any other vhost command. Further calls to
31 * VHOST_SET_OWNER fail until VHOST_RESET_OWNER is called. */
32#define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01)
33/* Give up ownership, and reset the device to default values.
34 * Allows subsequent call to VHOST_SET_OWNER to succeed. */
35#define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02)
36
37/* Set up/modify memory layout */
38#define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory)
39
40/* Write logging setup. */
41/* Memory writes can optionally be logged by setting bit at an offset
42 * (calculated from the physical address) from specified log base.
43 * The bit is set using an atomic 32 bit operation. */
44/* Set base address for logging. */
45#define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64)
46/* Specify an eventfd file descriptor to signal on log write. */
47#define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int)
48/* By default, a device gets one vhost_worker that its virtqueues share. This
49 * command allows the owner of the device to create an additional vhost_worker
50 * for the device. It can later be bound to 1 or more of its virtqueues using
51 * the VHOST_ATTACH_VRING_WORKER command.
52 *
53 * This must be called after VHOST_SET_OWNER and the caller must be the owner
54 * of the device. The new thread will inherit caller's cgroups and namespaces,
55 * and will share the caller's memory space. The new thread will also be
56 * counted against the caller's RLIMIT_NPROC value.
57 *
58 * The worker's ID used in other commands will be returned in
59 * vhost_worker_state.
60 */
61#define VHOST_NEW_WORKER _IOR(VHOST_VIRTIO, 0x8, struct vhost_worker_state)
62/* Free a worker created with VHOST_NEW_WORKER if it's not attached to any
63 * virtqueue. If userspace is not able to call this for workers its created,
64 * the kernel will free all the device's workers when the device is closed.
65 */
66#define VHOST_FREE_WORKER _IOW(VHOST_VIRTIO, 0x9, struct vhost_worker_state)
67
68/* Ring setup. */
69/* Set number of descriptors in ring. This parameter can not
70 * be modified while ring is running (bound to a device). */
71#define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state)
72/* Set addresses for the ring. */
73#define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr)
74/* Base value where queue looks for available descriptors */
75#define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
76/* Get accessor: reads index, writes value in num */
77#define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
78
79/* Set the vring byte order in num. Valid values are VHOST_VRING_LITTLE_ENDIAN
80 * or VHOST_VRING_BIG_ENDIAN (other values return -EINVAL).
81 * The byte order cannot be changed while the device is active: trying to do so
82 * returns -EBUSY.
83 * This is a legacy only API that is simply ignored when VIRTIO_F_VERSION_1 is
84 * set.
85 * Not all kernel configurations support this ioctl, but all configurations that
86 * support SET also support GET.
87 */
88#define VHOST_VRING_LITTLE_ENDIAN 0
89#define VHOST_VRING_BIG_ENDIAN 1
90#define VHOST_SET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_state)
91#define VHOST_GET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state)
92/* Attach a vhost_worker created with VHOST_NEW_WORKER to one of the device's
93 * virtqueues.
94 *
95 * This will replace the virtqueue's existing worker. If the replaced worker
96 * is no longer attached to any virtqueues, it can be freed with
97 * VHOST_FREE_WORKER.
98 */
99#define VHOST_ATTACH_VRING_WORKER _IOW(VHOST_VIRTIO, 0x15, \
100 struct vhost_vring_worker)
101/* Return the vring worker's ID */
102#define VHOST_GET_VRING_WORKER _IOWR(VHOST_VIRTIO, 0x16, \
103 struct vhost_vring_worker)
104
105/* The following ioctls use eventfd file descriptors to signal and poll
106 * for events. */
107
108/* Set eventfd to poll for added buffers */
109#define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file)
110/* Set eventfd to signal when buffers have beed used */
111#define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file)
112/* Set eventfd to signal an error */
113#define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
114/* Set busy loop timeout (in us) */
115#define VHOST_SET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x23, \
116 struct vhost_vring_state)
117/* Get busy loop timeout (in us) */
118#define VHOST_GET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x24, \
119 struct vhost_vring_state)
120
121/* Set or get vhost backend capability */
122
123#define VHOST_SET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x25, __u64)
124#define VHOST_GET_BACKEND_FEATURES _IOR(VHOST_VIRTIO, 0x26, __u64)
125
126/* VHOST_NET specific defines */
127
128/* Attach virtio net ring to a raw socket, or tap device.
129 * The socket must be already bound to an ethernet device, this device will be
130 * used for transmit. Pass fd -1 to unbind from the socket and the transmit
131 * device. This can be used to stop the ring (e.g. for migration). */
132#define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file)
133
134/* VHOST_SCSI specific defines */
135
136#define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target)
137#define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target)
138/* Changing this breaks userspace. */
139#define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int)
140/* Set and get the events missed flag */
141#define VHOST_SCSI_SET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x43, __u32)
142#define VHOST_SCSI_GET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x44, __u32)
143
144/* VHOST_VSOCK specific defines */
145
146#define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u64)
147#define VHOST_VSOCK_SET_RUNNING _IOW(VHOST_VIRTIO, 0x61, int)
148
149/* VHOST_VDPA specific defines */
150
151/* Get the device id. The device ids follow the same definition of
152 * the device id defined in virtio-spec.
153 */
154#define VHOST_VDPA_GET_DEVICE_ID _IOR(VHOST_VIRTIO, 0x70, __u32)
155/* Get and set the status. The status bits follow the same definition
156 * of the device status defined in virtio-spec.
157 */
158#define VHOST_VDPA_GET_STATUS _IOR(VHOST_VIRTIO, 0x71, __u8)
159#define VHOST_VDPA_SET_STATUS _IOW(VHOST_VIRTIO, 0x72, __u8)
160/* Get and set the device config. The device config follows the same
161 * definition of the device config defined in virtio-spec.
162 */
163#define VHOST_VDPA_GET_CONFIG _IOR(VHOST_VIRTIO, 0x73, \
164 struct vhost_vdpa_config)
165#define VHOST_VDPA_SET_CONFIG _IOW(VHOST_VIRTIO, 0x74, \
166 struct vhost_vdpa_config)
167/* Enable/disable the ring. */
168#define VHOST_VDPA_SET_VRING_ENABLE _IOW(VHOST_VIRTIO, 0x75, \
169 struct vhost_vring_state)
170/* Get the max ring size. */
171#define VHOST_VDPA_GET_VRING_NUM _IOR(VHOST_VIRTIO, 0x76, __u16)
172
173/* Set event fd for config interrupt*/
174#define VHOST_VDPA_SET_CONFIG_CALL _IOW(VHOST_VIRTIO, 0x77, int)
175
176/* Get the valid iova range */
177#define VHOST_VDPA_GET_IOVA_RANGE _IOR(VHOST_VIRTIO, 0x78, \
178 struct vhost_vdpa_iova_range)
179/* Get the config size */
180#define VHOST_VDPA_GET_CONFIG_SIZE _IOR(VHOST_VIRTIO, 0x79, __u32)
181
182/* Get the number of address spaces. */
183#define VHOST_VDPA_GET_AS_NUM _IOR(VHOST_VIRTIO, 0x7A, unsigned int)
184
185/* Get the group for a virtqueue: read index, write group in num,
186 * The virtqueue index is stored in the index field of
187 * vhost_vring_state. The group for this specific virtqueue is
188 * returned via num field of vhost_vring_state.
189 */
190#define VHOST_VDPA_GET_VRING_GROUP _IOWR(VHOST_VIRTIO, 0x7B, \
191 struct vhost_vring_state)
192/* Set the ASID for a virtqueue group. The group index is stored in
193 * the index field of vhost_vring_state, the ASID associated with this
194 * group is stored at num field of vhost_vring_state.
195 */
196#define VHOST_VDPA_SET_GROUP_ASID _IOW(VHOST_VIRTIO, 0x7C, \
197 struct vhost_vring_state)
198
199/* Suspend a device so it does not process virtqueue requests anymore
200 *
201 * After the return of ioctl the device must preserve all the necessary state
202 * (the virtqueue vring base plus the possible device specific states) that is
203 * required for restoring in the future. The device must not change its
204 * configuration after that point.
205 */
206#define VHOST_VDPA_SUSPEND _IO(VHOST_VIRTIO, 0x7D)
207
208/* Resume a device so it can resume processing virtqueue requests
209 *
210 * After the return of this ioctl the device will have restored all the
211 * necessary states and it is fully operational to continue processing the
212 * virtqueue descriptors.
213 */
214#define VHOST_VDPA_RESUME _IO(VHOST_VIRTIO, 0x7E)
215
216/* Get the group for the descriptor table including driver & device areas
217 * of a virtqueue: read index, write group in num.
218 * The virtqueue index is stored in the index field of vhost_vring_state.
219 * The group ID of the descriptor table for this specific virtqueue
220 * is returned via num field of vhost_vring_state.
221 */
222#define VHOST_VDPA_GET_VRING_DESC_GROUP _IOWR(VHOST_VIRTIO, 0x7F, \
223 struct vhost_vring_state)
224
225
226/* Get the count of all virtqueues */
227#define VHOST_VDPA_GET_VQS_COUNT _IOR(VHOST_VIRTIO, 0x80, __u32)
228
229/* Get the number of virtqueue groups. */
230#define VHOST_VDPA_GET_GROUP_NUM _IOR(VHOST_VIRTIO, 0x81, __u32)
231
232/* Get the queue size of a specific virtqueue.
233 * userspace set the vring index in vhost_vring_state.index
234 * kernel set the queue size in vhost_vring_state.num
235 */
236#define VHOST_VDPA_GET_VRING_SIZE _IOWR(VHOST_VIRTIO, 0x82, \
237 struct vhost_vring_state)
238
239/* Extended features manipulation */
240#define VHOST_GET_FEATURES_ARRAY _IOR(VHOST_VIRTIO, 0x83, \
241 struct vhost_features_array)
242#define VHOST_SET_FEATURES_ARRAY _IOW(VHOST_VIRTIO, 0x83, \
243 struct vhost_features_array)
244
245/* fork_owner values for vhost */
246#define VHOST_FORK_OWNER_KTHREAD 0
247#define VHOST_FORK_OWNER_TASK 1
248
249/**
250 * VHOST_SET_FORK_FROM_OWNER - Set the fork_owner flag for the vhost device,
251 * This ioctl must called before VHOST_SET_OWNER.
252 * Only available when CONFIG_VHOST_ENABLE_FORK_OWNER_CONTROL=y
253 *
254 * @param fork_owner: An 8-bit value that determines the vhost thread mode
255 *
256 * When fork_owner is set to VHOST_FORK_OWNER_TASK(default value):
257 * - Vhost will create vhost worker as tasks forked from the owner,
258 * inheriting all of the owner's attributes.
259 *
260 * When fork_owner is set to VHOST_FORK_OWNER_KTHREAD:
261 * - Vhost will create vhost workers as kernel threads.
262 */
263#define VHOST_SET_FORK_FROM_OWNER _IOW(VHOST_VIRTIO, 0x84, __u8)
264
265/**
266 * VHOST_GET_FORK_OWNER - Get the current fork_owner flag for the vhost device.
267 * Only available when CONFIG_VHOST_ENABLE_FORK_OWNER_CONTROL=y
268 *
269 * @return: An 8-bit value indicating the current thread mode.
270 */
271#define VHOST_GET_FORK_FROM_OWNER _IOR(VHOST_VIRTIO, 0x85, __u8)
272
273#endif