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