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 #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 /* 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 count of all virtqueues */
 183 #define VHOST_VDPA_GET_VQS_COUNT        _IOR(VHOST_VIRTIO, 0x80, __u32)
 184
 185 /* Get the number of virtqueue groups. */
 186 #define VHOST_VDPA_GET_GROUP_NUM        _IOR(VHOST_VIRTIO, 0x81, __u32)
 187
 188 /* Get the number of address spaces. */
 189 #define VHOST_VDPA_GET_AS_NUM           _IOR(VHOST_VIRTIO, 0x7A, unsigned int)
 190
 191 /* Get the group for a virtqueue: read index, write group in num,
 192  * The virtqueue index is stored in the index field of
 193  * vhost_vring_state. The group for this specific virtqueue is
 194  * returned via num field of vhost_vring_state.
 195  */
 196 #define VHOST_VDPA_GET_VRING_GROUP      _IOWR(VHOST_VIRTIO, 0x7B,       \
 197                                               struct vhost_vring_state)
 198 /* Set the ASID for a virtqueue group. The group index is stored in
 199  * the index field of vhost_vring_state, the ASID associated with this
 200  * group is stored at num field of vhost_vring_state.
 201  */
 202 #define VHOST_VDPA_SET_GROUP_ASID       _IOW(VHOST_VIRTIO, 0x7C, \
 203                                              struct vhost_vring_state)
 204
 205 /* Suspend a device so it does not process virtqueue requests anymore
 206  *
 207  * After the return of ioctl the device must preserve all the necessary state
 208  * (the virtqueue vring base plus the possible device specific states) that is
 209  * required for restoring in the future. The device must not change its
 210  * configuration after that point.
 211  */
 212 #define VHOST_VDPA_SUSPEND              _IO(VHOST_VIRTIO, 0x7D)
 213
 214 /* Resume a device so it can resume processing virtqueue requests
 215  *
 216  * After the return of this ioctl the device will have restored all the
 217  * necessary states and it is fully operational to continue processing the
 218  * virtqueue descriptors.
 219  */
 220 #define VHOST_VDPA_RESUME               _IO(VHOST_VIRTIO, 0x7E)
 221
 222 /* Get the group for the descriptor table including driver & device areas
 223  * of a virtqueue: read index, write group in num.
 224  * The virtqueue index is stored in the index field of vhost_vring_state.
 225  * The group ID of the descriptor table for this specific virtqueue
 226  * is returned via num field of vhost_vring_state.
 227  */
 228 #define VHOST_VDPA_GET_VRING_DESC_GROUP _IOWR(VHOST_VIRTIO, 0x7F,       \
 229                                               struct vhost_vring_state)
 230 #endif