Module vmm_vhost::message

Define communication messages for the vhost-user protocol.

For message definition, please refer to the vhost-user spec.

Structs

• DescStatePacked
  Inflight I/O descriptor state for packed virtqueues
• DescStateSplit
  Inflight I/O descriptor state for split virtqueues
• QueueRegionPacked
  Inflight I/O queue region for packed virtqueues
• QueueRegionSplit
  Inflight I/O queue region for split virtqueues
• VhostSharedMemoryRegion
  Virtio shared memory descriptor.
• VhostUserConfig
  Message to read/write device configuration space.
• VhostUserConfigFlags
  Flags for the device configuration message.
• VhostUserEmptyMessage
  A generic message for empty message. ZST in repr(C) has same type layout as repr(rust)
• VhostUserEmptyMsg
  An empty message.
• VhostUserExternalMapMsg
  Backend request message to map external memory into a shared memory region.
• VhostUserGpuMapMsg
  Backend request message to map GPU memory into a shared memory region.
• VhostUserHeaderFlag
  Common message flags for vhost-user requests and replies.
• VhostUserInflight
  Single memory region descriptor as payload for ADD_MEM_REG and REM_MEM_REG requests. This struct is defined by qemu and compiles with arch-dependent padding. Interestingly, all our supported archs (arm, aarch64, x86_64) has same data layout for this type.
• VhostUserMemory
  Memory region descriptor for the SET_MEM_TABLE request.
• VhostUserMemoryRegion
  Memory region descriptors as payload for the SET_MEM_TABLE request.
• VhostUserMsgHeader
  Common message header for vhost-user requests and replies. A vhost-user message consists of 3 header fields and an optional payload. All numbers are in the machine native byte order.
• VhostUserProtocolFeatures
  Vhost-user protocol feature flags.
• VhostUserShmemMapMsg
  Backend request message to map a file into a shared memory region.
• VhostUserShmemMapMsgFlags
  Flags for SHMEM_MAP messages.
• VhostUserShmemUnmapMsg
  Backend request message to unmap part of a shared memory region.
• VhostUserSingleMemoryRegion
  Single memory region descriptor as payload for ADD_MEM_REG and REM_MEM_REG requests.
• VhostUserSuccess
  A generic message to encapsulate a success or failure. use i8 instead of bool to allow FromBytes to be derived. type layout is same for all supported architectures.
• VhostUserU64
  A generic message to encapsulate a 64-bit value.
• VhostUserVringAddr
  Vring address descriptor.
• VhostUserVringAddrFlags
  Flags for vring address.
• VhostUserVringState
  Vring state descriptor.

Enums

• BackendReq
  Type of requests sending from backends to frontends.
• FrontendReq
  Type of requests sent to the backend.
• ReqError
  Error when converting an integer to an enum value.

Constants

• MAX_ATTACHED_FD_ENTRIES
  The VhostUserMemory message has variable message size and variable number of attached file descriptors. Each user memory region entry in the message payload occupies 32 bytes, so setting maximum number of attached file descriptors based on the maximum message size. But rust only implements Default and AsMut traits for arrays with 0 - 32 entries, so further reduce the maximum number…
• VHOST_USER_CONFIG_OFFSET
  Starting position (inclusion) of the device configuration space in virtio devices.
• VHOST_USER_CONFIG_SIZE
  Ending position (exclusion) of the device configuration space in virtio devices.
• VHOST_USER_F_PROTOCOL_FEATURES
  Virtio feature flag for the vhost-user protocol features.
• VHOST_USER_MAX_VRINGS
  Maximum number of vrings supported.
• VIRTIO_F_RING_PACKED

Traits

• Req
  Message type. Either [FrontendReq] or [BackendReq].
• VhostUserMsgValidator
  Vhost message Validator.

Type Definitions

• VhostUserConfigPayload
  Payload for the VhostUserConfig message.
• VhostUserMemoryPayload
  Payload of the VhostUserMemory message.