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