@@ -1,3 +1,5 @@
+.. _vhost_user_rng:
+
QEMU vhost-user-rng - RNG emulation
===================================
@@ -8,13 +8,76 @@ outside of QEMU itself. To do this there are a number of things
required.
vhost-user device
-===================
+=================
These are simple stub devices that ensure the VirtIO device is visible
to the guest. The code is mostly boilerplate although each device has
a ``chardev`` option which specifies the ID of the ``--chardev``
device that connects via a socket to the vhost-user *daemon*.
+Each device will have an virtio-mmio and virtio-pci variant. See your
+platform details for what sort of virtio bus to use.
+
+.. list-table:: vhost-user devices
+ :widths: 20 20 60
+ :header-rows: 1
+
+ * - Device
+ - Type
+ - Notes
+ * - vhost-user-blk
+ - Block storage
+ - See contrib/vhost-user-blk
+ * - vhost-user-fs
+ - File based storage driver
+ - See https://gitlab.com/virtio-fs/virtiofsd
+ * - vhost-user-gpio
+ - Proxy gpio pins to host
+ - See https://github.com/rust-vmm/vhost-device
+ * - vhost-user-gpu
+ - GPU driver
+ - See contrib/vhost-user-gpu
+ * - vhost-user-i2c
+ - Proxy i2c devices to host
+ - See https://github.com/rust-vmm/vhost-device
+ * - vhost-user-input
+ - Generic input driver
+ - See contrib/vhost-user-input
+ * - vhost-user-rng
+ - Entropy driver
+ - :ref:`vhost_user_rng`
+ * - vhost-user-scmi
+ - System Control and Management Interface
+ - See https://github.com/rust-vmm/vhost-device
+ * - vhost-user-snd
+ - Audio device
+ - See https://github.com/rust-vmm/vhost-device/staging
+ * - vhost-user-scsi
+ - SCSI based storage
+ - See contrib/vhost-user-scsi
+ * - vhost-user-vsock
+ - Socket based communication
+ - See https://github.com/rust-vmm/vhost-device
+
+The referenced *daemons* are not exhaustive, any conforming backend
+implementing the device and using the vhost-user protocol should work.
+
+vhost-user-device
+^^^^^^^^^^^^^^^^^
+
+The vhost-user-device is a generic development device intended for
+expert use while developing new backends. The user needs to specify
+all the required parameters including:
+
+ - Device ``virtio-id``
+ - The ``num_vqs`` it needs and their ``vq_size``
+ - The ``config_size`` if needed
+
+.. note::
+ To prevent user confusion you cannot currently instantiate
+ vhost-user-device without first patching out ``.abstract = true`` in
+ the ``vhost-user-device.c`` file and rebuilding.
+
vhost-user daemon
=================
Make it clear the vhost-user-device is intended for expert use only. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20231009095937.195728-7-alex.bennee@linaro.org> --- v5 - split vhost-user-device out of the table - sort the table alphabetically - add sound and scmi devices v6 - add note re vhost-user-device --- docs/system/devices/vhost-user-rng.rst | 2 + docs/system/devices/vhost-user.rst | 65 +++++++++++++++++++++++++- 2 files changed, 66 insertions(+), 1 deletion(-)