843a03590b
In preparation to upgrade to Rust version 1.63.0, address clippy warning demanding that 'Eq' be derived when 'PartialEq' is. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> |
||
|---|---|---|
| .. | ||
| src | ||
| Cargo.toml | ||
| README.md | ||
vhost-device-gpio - GPIO emulation backend daemon
Description
This program is a vhost-user backend that emulates a VirtIO GPIO device. This program takes a list of gpio devices on the host OS and then talks to them via the /dev/gpiochip{X} interface when a request comes from the guest OS for an GPIO device.
This program is tested with QEMU's -device vhost-user-gpio-pci but should
work with any virtual machine monitor (VMM) that supports vhost-user. See the
Examples section below.
Synopsis
vhost-device-gpio [OPTIONS]
Options
.. program:: vhost-device-gpio
.. option:: -h, --help
Print help.
.. option:: -s, --socket-path=PATH
Location of vhost-user Unix domain sockets, this path will be suffixed with 0,1,2..socket_count-1.
.. option:: -c, --socket-count=INT
Number of guests (sockets) to attach to, default set to 1.
.. option:: -l, --device-list=GPIO-DEVICES
GPIO device list at the host OS in the format: [:]
Example: --device-list "2:4:7"
Here, each GPIO devices correspond to a separate guest instance, i.e. the number of devices in the device-list must match the number of sockets in the --socket-count. For example, the GPIO device 0 will be allocated to the guest with "0" path.
Examples
The daemon should be started first:
::
host# vhost-device-gpio --socket-path=gpio.sock --socket-count=1 --device-list 0:3
The QEMU invocation needs to create a chardev socket the device can use to communicate as well as share the guests memory over a memfd.
::
host# qemu-system
-chardev socket,path=vgpio.sock,id=vgpio
-device vhost-user-gpio-pci,chardev=vgpio,id=gpio
-m 4096
-object memory-backend-file,id=mem,size=4G,mem-path=/dev/shm,share=on
-numa node,memdev=mem
...