xref: /qemu/linux-headers/linux/vhost.h (revision b2a3cbb8)
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_OWNER_SET fail until VHOST_OWNER_RESET 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_OWNER_SET 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 
49 /* Ring setup. */
50 /* Set number of descriptors in ring. This parameter can not
51  * be modified while ring is running (bound to a device). */
52 #define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state)
53 /* Set addresses for the ring. */
54 #define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr)
55 /* Base value where queue looks for available descriptors */
56 #define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
57 /* Get accessor: reads index, writes value in num */
58 #define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state)
59 
60 /* Set the vring byte order in num. Valid values are VHOST_VRING_LITTLE_ENDIAN
61  * or VHOST_VRING_BIG_ENDIAN (other values return -EINVAL).
62  * The byte order cannot be changed while the device is active: trying to do so
63  * returns -EBUSY.
64  * This is a legacy only API that is simply ignored when VIRTIO_F_VERSION_1 is
65  * set.
66  * Not all kernel configurations support this ioctl, but all configurations that
67  * support SET also support GET.
68  */
69 #define VHOST_VRING_LITTLE_ENDIAN 0
70 #define VHOST_VRING_BIG_ENDIAN 1
71 #define VHOST_SET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_state)
72 #define VHOST_GET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state)
73 
74 /* The following ioctls use eventfd file descriptors to signal and poll
75  * for events. */
76 
77 /* Set eventfd to poll for added buffers */
78 #define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file)
79 /* Set eventfd to signal when buffers have beed used */
80 #define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file)
81 /* Set eventfd to signal an error */
82 #define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
83 /* Set busy loop timeout (in us) */
84 #define VHOST_SET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x23,	\
85 					 struct vhost_vring_state)
86 /* Get busy loop timeout (in us) */
87 #define VHOST_GET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x24,	\
88 					 struct vhost_vring_state)
89 
90 /* Set or get vhost backend capability */
91 
92 #define VHOST_SET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x25, __u64)
93 #define VHOST_GET_BACKEND_FEATURES _IOR(VHOST_VIRTIO, 0x26, __u64)
94 
95 /* VHOST_NET specific defines */
96 
97 /* Attach virtio net ring to a raw socket, or tap device.
98  * The socket must be already bound to an ethernet device, this device will be
99  * used for transmit.  Pass fd -1 to unbind from the socket and the transmit
100  * device.  This can be used to stop the ring (e.g. for migration). */
101 #define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file)
102 
103 /* VHOST_SCSI specific defines */
104 
105 #define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target)
106 #define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target)
107 /* Changing this breaks userspace. */
108 #define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int)
109 /* Set and get the events missed flag */
110 #define VHOST_SCSI_SET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x43, __u32)
111 #define VHOST_SCSI_GET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x44, __u32)
112 
113 /* VHOST_VSOCK specific defines */
114 
115 #define VHOST_VSOCK_SET_GUEST_CID	_IOW(VHOST_VIRTIO, 0x60, __u64)
116 #define VHOST_VSOCK_SET_RUNNING		_IOW(VHOST_VIRTIO, 0x61, int)
117 
118 /* VHOST_VDPA specific defines */
119 
120 /* Get the device id. The device ids follow the same definition of
121  * the device id defined in virtio-spec.
122  */
123 #define VHOST_VDPA_GET_DEVICE_ID	_IOR(VHOST_VIRTIO, 0x70, __u32)
124 /* Get and set the status. The status bits follow the same definition
125  * of the device status defined in virtio-spec.
126  */
127 #define VHOST_VDPA_GET_STATUS		_IOR(VHOST_VIRTIO, 0x71, __u8)
128 #define VHOST_VDPA_SET_STATUS		_IOW(VHOST_VIRTIO, 0x72, __u8)
129 /* Get and set the device config. The device config follows the same
130  * definition of the device config defined in virtio-spec.
131  */
132 #define VHOST_VDPA_GET_CONFIG		_IOR(VHOST_VIRTIO, 0x73, \
133 					     struct vhost_vdpa_config)
134 #define VHOST_VDPA_SET_CONFIG		_IOW(VHOST_VIRTIO, 0x74, \
135 					     struct vhost_vdpa_config)
136 /* Enable/disable the ring. */
137 #define VHOST_VDPA_SET_VRING_ENABLE	_IOW(VHOST_VIRTIO, 0x75, \
138 					     struct vhost_vring_state)
139 /* Get the max ring size. */
140 #define VHOST_VDPA_GET_VRING_NUM	_IOR(VHOST_VIRTIO, 0x76, __u16)
141 
142 /* Set event fd for config interrupt*/
143 #define VHOST_VDPA_SET_CONFIG_CALL	_IOW(VHOST_VIRTIO, 0x77, int)
144 
145 /* Get the valid iova range */
146 #define VHOST_VDPA_GET_IOVA_RANGE	_IOR(VHOST_VIRTIO, 0x78, \
147 					     struct vhost_vdpa_iova_range)
148 /* Get the config size */
149 #define VHOST_VDPA_GET_CONFIG_SIZE	_IOR(VHOST_VIRTIO, 0x79, __u32)
150 
151 /* Get the count of all virtqueues */
152 #define VHOST_VDPA_GET_VQS_COUNT	_IOR(VHOST_VIRTIO, 0x80, __u32)
153 
154 /* Get the number of virtqueue groups. */
155 #define VHOST_VDPA_GET_GROUP_NUM	_IOR(VHOST_VIRTIO, 0x81, __u32)
156 
157 /* Get the number of address spaces. */
158 #define VHOST_VDPA_GET_AS_NUM		_IOR(VHOST_VIRTIO, 0x7A, unsigned int)
159 
160 /* Get the group for a virtqueue: read index, write group in num,
161  * The virtqueue index is stored in the index field of
162  * vhost_vring_state. The group for this specific virtqueue is
163  * returned via num field of vhost_vring_state.
164  */
165 #define VHOST_VDPA_GET_VRING_GROUP	_IOWR(VHOST_VIRTIO, 0x7B,	\
166 					      struct vhost_vring_state)
167 /* Set the ASID for a virtqueue group. The group index is stored in
168  * the index field of vhost_vring_state, the ASID associated with this
169  * group is stored at num field of vhost_vring_state.
170  */
171 #define VHOST_VDPA_SET_GROUP_ASID	_IOW(VHOST_VIRTIO, 0x7C, \
172 					     struct vhost_vring_state)
173 
174 /* Suspend a device so it does not process virtqueue requests anymore
175  *
176  * After the return of ioctl the device must preserve all the necessary state
177  * (the virtqueue vring base plus the possible device specific states) that is
178  * required for restoring in the future. The device must not change its
179  * configuration after that point.
180  */
181 #define VHOST_VDPA_SUSPEND		_IO(VHOST_VIRTIO, 0x7D)
182 
183 #endif
184