LXR qemu/linux-headers/linux/vhost.h

   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