It is not necessary to mention which side is sending/receiving each payload; it is more interesting to say which is the request and which is the reply. This also matches what vhost-user-gpu.rst already does.
While at it, ensure that all messages list both the request and the reply payload. Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> --- docs/interop/vhost-user.rst | 166 +++++++++++++++++++++--------------- 1 file changed, 98 insertions(+), 68 deletions(-) diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst index d6085f7045..4c46b16416 100644 --- a/docs/interop/vhost-user.rst +++ b/docs/interop/vhost-user.rst @@ -838,11 +838,14 @@ Protocol features Master message types -------------------- +For this type of message, the request is sent by the master and the +reply is sent by the slave. + ``VHOST_USER_GET_FEATURES`` :id: 1 :equivalent ioctl: ``VHOST_GET_FEATURES`` - :master payload: N/A - :slave payload: ``u64`` + :request payload: N/A + :reply payload: ``u64`` Get from the underlying vhost implementation the features bitmask. Feature bit ``VHOST_USER_F_PROTOCOL_FEATURES`` signals slave support @@ -852,7 +855,8 @@ Master message types ``VHOST_USER_SET_FEATURES`` :id: 2 :equivalent ioctl: ``VHOST_SET_FEATURES`` - :master payload: ``u64`` + :request payload: ``u64`` + :reply payload: N/A Enable features in the underlying vhost implementation using a bitmask. Feature bit ``VHOST_USER_F_PROTOCOL_FEATURES`` signals @@ -862,8 +866,8 @@ Master message types ``VHOST_USER_GET_PROTOCOL_FEATURES`` :id: 15 :equivalent ioctl: ``VHOST_GET_FEATURES`` - :master payload: N/A - :slave payload: ``u64`` + :request payload: N/A + :reply payload: ``u64`` Get the protocol feature bitmask from the underlying vhost implementation. Only legal if feature bit @@ -878,7 +882,8 @@ Master message types ``VHOST_USER_SET_PROTOCOL_FEATURES`` :id: 16 :equivalent ioctl: ``VHOST_SET_FEATURES`` - :master payload: ``u64`` + :request payload: ``u64`` + :reply payload: N/A Enable protocol features in the underlying vhost implementation. @@ -892,7 +897,8 @@ Master message types ``VHOST_USER_SET_OWNER`` :id: 3 :equivalent ioctl: ``VHOST_SET_OWNER`` - :master payload: N/A + :request payload: N/A + :reply payload: N/A Issued when a new connection is established. It sets the current *master* as an owner of the session. This can be used on the *slave* @@ -900,7 +906,8 @@ Master message types ``VHOST_USER_RESET_OWNER`` :id: 4 - :master payload: N/A + :request payload: N/A + :reply payload: N/A .. admonition:: Deprecated @@ -913,8 +920,8 @@ Master message types ``VHOST_USER_SET_MEM_TABLE`` :id: 5 :equivalent ioctl: ``VHOST_SET_MEM_TABLE`` - :master payload: memory regions description - :slave payload: (postcopy only) memory regions description + :request payload: memory regions description + :reply payload: (postcopy only) memory regions description Sets the memory map regions on the slave so it can translate the vring addresses. In the ancillary data there is an array of file @@ -937,8 +944,8 @@ Master message types ``VHOST_USER_SET_LOG_BASE`` :id: 6 :equivalent ioctl: ``VHOST_SET_LOG_BASE`` - :master payload: u64 - :slave payload: N/A + :request payload: u64 + :reply payload: N/A Sets logging shared memory space. @@ -950,44 +957,48 @@ Master message types ``VHOST_USER_SET_LOG_FD`` :id: 7 :equivalent ioctl: ``VHOST_SET_LOG_FD`` - :master payload: N/A + :request payload: N/A + :reply payload: N/A Sets the logging file descriptor, which is passed as ancillary data. ``VHOST_USER_SET_VRING_NUM`` :id: 8 :equivalent ioctl: ``VHOST_SET_VRING_NUM`` - :master payload: vring state description + :request payload: vring state description + :reply payload: N/A Set the size of the queue. ``VHOST_USER_SET_VRING_ADDR`` :id: 9 :equivalent ioctl: ``VHOST_SET_VRING_ADDR`` - :master payload: vring address description - :slave payload: N/A + :request payload: vring address description + :reply payload: N/A Sets the addresses of the different aspects of the vring. ``VHOST_USER_SET_VRING_BASE`` :id: 10 :equivalent ioctl: ``VHOST_SET_VRING_BASE`` - :master payload: vring state description + :request payload: vring state description + :reply payload: N/A Sets the base offset in the available vring. ``VHOST_USER_GET_VRING_BASE`` :id: 11 :equivalent ioctl: ``VHOST_USER_GET_VRING_BASE`` - :master payload: vring state description - :slave payload: vring state description + :request payload: vring state description + :reply payload: vring state description Get the available vring base offset. ``VHOST_USER_SET_VRING_KICK`` :id: 12 :equivalent ioctl: ``VHOST_SET_VRING_KICK`` - :master payload: ``u64`` + :request payload: ``u64`` + :reply payload: N/A Set the event file descriptor for adding buffers to the vring. It is passed in the ancillary data. @@ -1005,7 +1016,8 @@ Master message types ``VHOST_USER_SET_VRING_CALL`` :id: 13 :equivalent ioctl: ``VHOST_SET_VRING_CALL`` - :master payload: ``u64`` + :request payload: ``u64`` + :reply payload: N/A Set the event file descriptor to signal when buffers are used. It is passed in the ancillary data. @@ -1023,7 +1035,8 @@ Master message types ``VHOST_USER_SET_VRING_ERR`` :id: 14 :equivalent ioctl: ``VHOST_SET_VRING_ERR`` - :master payload: ``u64`` + :request payload: ``u64`` + :reply payload: N/A Set the event file descriptor to signal when error occurs. It is passed in the ancillary data. @@ -1040,8 +1053,8 @@ Master message types ``VHOST_USER_GET_QUEUE_NUM`` :id: 17 :equivalent ioctl: N/A - :master payload: N/A - :slave payload: u64 + :request payload: N/A + :reply payload: u64 Query how many queues the backend supports. @@ -1052,7 +1065,8 @@ Master message types ``VHOST_USER_SET_VRING_ENABLE`` :id: 18 :equivalent ioctl: N/A - :master payload: vring state description + :request payload: vring state description + :reply payload: N/A Signal slave to enable or disable corresponding vring. @@ -1062,7 +1076,8 @@ Master message types ``VHOST_USER_SEND_RARP`` :id: 19 :equivalent ioctl: N/A - :master payload: ``u64`` + :request payload: ``u64`` + :reply payload: N/A Ask vhost user backend to broadcast a fake RARP to notify the migration is terminated for guest that does not support GUEST_ANNOUNCE. @@ -1077,7 +1092,8 @@ Master message types ``VHOST_USER_NET_SET_MTU`` :id: 20 :equivalent ioctl: N/A - :master payload: ``u64`` + :request payload: ``u64`` + :reply payload: N/A Set host MTU value exposed to the guest. @@ -1094,7 +1110,8 @@ Master message types ``VHOST_USER_SET_SLAVE_REQ_FD`` :id: 21 :equivalent ioctl: N/A - :master payload: N/A + :request payload: N/A + :reply payload: N/A Set the socket file descriptor for slave initiated requests. It is passed in the ancillary data. @@ -1109,8 +1126,8 @@ Master message types ``VHOST_USER_IOTLB_MSG`` :id: 22 :equivalent ioctl: N/A (equivalent to ``VHOST_IOTLB_MSG`` message type) - :master payload: ``struct vhost_iotlb_msg`` - :slave payload: ``u64`` + :request payload: ``struct vhost_iotlb_msg`` + :reply payload: ``u64`` Send IOTLB messages with ``struct vhost_iotlb_msg`` as payload. @@ -1124,7 +1141,8 @@ Master message types ``VHOST_USER_SET_VRING_ENDIAN`` :id: 23 :equivalent ioctl: ``VHOST_SET_VRING_ENDIAN`` - :master payload: vring state description + :request payload: vring state description + :reply payload: N/A Set the endianness of a VQ for legacy devices. Little-endian is indicated with state.num set to 0 and big-endian is indicated with @@ -1139,8 +1157,8 @@ Master message types ``VHOST_USER_GET_CONFIG`` :id: 24 :equivalent ioctl: N/A - :master payload: virtio device config space - :slave payload: virtio device config space + :request payload: virtio device config space + :reply payload: virtio device config space When ``VHOST_USER_PROTOCOL_F_CONFIG`` is negotiated, this message is submitted by the vhost-user master to fetch the contents of the @@ -1153,8 +1171,8 @@ Master message types ``VHOST_USER_SET_CONFIG`` :id: 25 :equivalent ioctl: N/A - :master payload: virtio device config space - :slave payload: N/A + :request payload: virtio device config space + :reply payload: N/A When ``VHOST_USER_PROTOCOL_F_CONFIG`` is negotiated, this message is submitted by the vhost-user master when the Guest changes the virtio @@ -1166,8 +1184,8 @@ Master message types ``VHOST_USER_CREATE_CRYPTO_SESSION`` :id: 26 :equivalent ioctl: N/A - :master payload: crypto session description - :slave payload: crypto session description + :request payload: crypto session description + :reply payload: crypto session description Create a session for crypto operation. The server side must return the session id, 0 or positive for success, negative for failure. @@ -1179,7 +1197,8 @@ Master message types ``VHOST_USER_CLOSE_CRYPTO_SESSION`` :id: 27 :equivalent ioctl: N/A - :master payload: ``u64`` + :request payload: ``u64`` + :reply payload: N/A Close a session for crypto operation which was previously created by ``VHOST_USER_CREATE_CRYPTO_SESSION``. @@ -1191,8 +1210,8 @@ Master message types ``VHOST_USER_POSTCOPY_ADVISE`` :id: 28 - :master payload: N/A - :slave payload: userfault fd + :request payload: N/A + :reply payload: userfault fd When ``VHOST_USER_PROTOCOL_F_PAGEFAULT`` is supported, the master advises slave that a migration with postcopy enabled is underway, @@ -1201,7 +1220,8 @@ Master message types ``VHOST_USER_POSTCOPY_LISTEN`` :id: 29 - :master payload: N/A + :request payload: N/A + :reply payload: N/A Master advises slave that a transition to postcopy mode has happened. The slave must ensure that shared memory is registered @@ -1212,10 +1232,11 @@ Master message types ``VHOST_USER_POSTCOPY_END`` :id: 30 - :slave payload: ``u64`` + :request payload: N/A + :reply payload: ``u64`` Master advises that postcopy migration has now completed. The slave - must disable the userfaultfd. The response is an acknowledgement + must disable the userfaultfd. The reply is an acknowledgement only. When ``VHOST_USER_PROTOCOL_F_PAGEFAULT`` is supported, this message @@ -1227,7 +1248,8 @@ Master message types ``VHOST_USER_GET_INFLIGHT_FD`` :id: 31 :equivalent ioctl: N/A - :master payload: inflight description + :request payload: inflight description + :reply payload: N/A When ``VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD`` protocol feature has been successfully negotiated, this message is submitted by master to @@ -1238,7 +1260,8 @@ Master message types ``VHOST_USER_SET_INFLIGHT_FD`` :id: 32 :equivalent ioctl: N/A - :master payload: inflight description + :request payload: inflight description + :reply payload: N/A When ``VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD`` protocol feature has been successfully negotiated, this message is submitted by master to @@ -1248,7 +1271,8 @@ Master message types ``VHOST_USER_GPU_SET_SOCKET`` :id: 33 :equivalent ioctl: N/A - :master payload: N/A + :request payload: N/A + :reply payload: N/A Sets the GPU protocol socket file descriptor, which is passed as ancillary data. The GPU protocol is used to inform the master of @@ -1257,8 +1281,8 @@ Master message types ``VHOST_USER_RESET_DEVICE`` :id: 34 :equivalent ioctl: N/A - :master payload: N/A - :slave payload: N/A + :request payload: N/A + :reply payload: N/A Ask the vhost user backend to disable all rings and reset all internal device state to the initial state, ready to be @@ -1271,8 +1295,8 @@ Master message types ``VHOST_USER_VRING_KICK`` :id: 35 :equivalent ioctl: N/A - :slave payload: vring state description - :master payload: N/A + :request payload: vring state description + :reply payload: N/A When the ``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` protocol feature has been successfully negotiated, this message may be @@ -1285,7 +1309,8 @@ Master message types ``VHOST_USER_GET_MAX_MEM_SLOTS`` :id: 36 :equivalent ioctl: N/A - :slave payload: u64 + :request payload: N/A + :reply payload: u64 When the ``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol feature has been successfully negotiated, this message is submitted @@ -1298,7 +1323,8 @@ Master message types ``VHOST_USER_ADD_MEM_REG`` :id: 37 :equivalent ioctl: N/A - :slave payload: single memory region description + :request payload: N/A + :reply payload: single memory region description When the ``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol feature has been successfully negotiated, this message is submitted @@ -1313,7 +1339,8 @@ Master message types ``VHOST_USER_REM_MEM_REG`` :id: 38 :equivalent ioctl: N/A - :slave payload: single memory region description + :request payload: N/A + :reply payload: single memory region description When the ``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol feature has been successfully negotiated, this message is submitted @@ -1328,8 +1355,8 @@ Master message types ``VHOST_USER_SET_STATUS`` :id: 39 :equivalent ioctl: VHOST_VDPA_SET_STATUS - :slave payload: N/A - :master payload: ``u64`` + :request payload: ``u64`` + :reply payload: N/A When the ``VHOST_USER_PROTOCOL_F_STATUS`` protocol feature has been successfully negotiated, this message is submitted by the master to @@ -1339,8 +1366,8 @@ Master message types ``VHOST_USER_GET_STATUS`` :id: 40 :equivalent ioctl: VHOST_VDPA_GET_STATUS - :slave payload: ``u64`` - :master payload: N/A + :request payload: N/A + :reply payload: ``u64`` When the ``VHOST_USER_PROTOCOL_F_STATUS`` protocol feature has been successfully negotiated, this message is submitted by the master to @@ -1351,11 +1378,14 @@ Master message types Slave message types ------------------- +For this type of message, the request is sent by the slave and the reply +is sent by the master. + ``VHOST_USER_SLAVE_IOTLB_MSG`` :id: 1 :equivalent ioctl: N/A (equivalent to ``VHOST_IOTLB_MSG`` message type) - :slave payload: ``struct vhost_iotlb_msg`` - :master payload: N/A + :request payload: ``struct vhost_iotlb_msg`` + :reply payload: N/A Send IOTLB messages with ``struct vhost_iotlb_msg`` as payload. Slave sends such requests to notify of an IOTLB miss, or an IOTLB @@ -1369,8 +1399,8 @@ Slave message types ``VHOST_USER_SLAVE_CONFIG_CHANGE_MSG`` :id: 2 :equivalent ioctl: N/A - :slave payload: N/A - :master payload: N/A + :request payload: N/A + :reply payload: N/A When ``VHOST_USER_PROTOCOL_F_CONFIG`` is negotiated, vhost-user slave sends such messages to notify that the virtio device's @@ -1384,8 +1414,8 @@ Slave message types ``VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG`` :id: 3 :equivalent ioctl: N/A - :slave payload: vring area description - :master payload: N/A + :request payload: vring area description + :reply payload: N/A Sets host notifier for a specified queue. The queue index is contained in the ``u64`` field of the vring area description. The @@ -1407,8 +1437,8 @@ Slave message types ``VHOST_USER_SLAVE_VRING_CALL`` :id: 4 :equivalent ioctl: N/A - :slave payload: vring state description - :master payload: N/A + :request payload: vring state description + :reply payload: N/A When the ``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` protocol feature has been successfully negotiated, this message may be @@ -1421,8 +1451,8 @@ Slave message types ``VHOST_USER_SLAVE_VRING_ERR`` :id: 5 :equivalent ioctl: N/A - :slave payload: vring state description - :master payload: N/A + :request payload: vring state description + :reply payload: N/A When the ``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` protocol feature has been successfully negotiated, this message may be @@ -1448,7 +1478,7 @@ client MUST respond with a Payload ``VhostUserMsg`` indicating success or failure. The payload should be set to zero on success or non-zero on failure, unless the message already has an explicit reply body. -The response payload gives QEMU a deterministic indication of the result +The reply payload gives QEMU a deterministic indication of the result of the command. Today, QEMU is expected to terminate the main vhost-user loop upon receiving such errors. In future, qemu could be taught to be more resilient for selective requests. -- 2.26.2
