diff options
Diffstat (limited to 'docs/system/devices')
-rw-r--r-- | docs/system/devices/cxl.rst | 11 | ||||
-rw-r--r-- | docs/system/devices/igb.rst | 2 | ||||
-rw-r--r-- | docs/system/devices/net.rst | 68 | ||||
-rw-r--r-- | docs/system/devices/vfio-user.rst | 26 | ||||
-rw-r--r-- | docs/system/devices/vhost-user.rst | 20 |
5 files changed, 105 insertions, 22 deletions
diff --git a/docs/system/devices/cxl.rst b/docs/system/devices/cxl.rst index e307caf..ca15a0d 100644 --- a/docs/system/devices/cxl.rst +++ b/docs/system/devices/cxl.rst @@ -384,6 +384,17 @@ An example of 4 devices below a switch suitable for 1, 2 or 4 way interleave:: -device cxl-type3,bus=swport3,persistent-memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem3,sn=0x4 \ -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G,cxl-fmw.0.interleave-granularity=4k +A simple arm/virt example featuring a single direct connected CXL Type 3 +Volatile Memory device:: + + qemu-system-aarch64 -M virt,gic-version=3,cxl=on -m 4g,maxmem=8g,slots=4 -cpu max -smp 4 \ + ... + -object memory-backend-ram,id=vmem0,share=on,size=256M \ + -device pxb-cxl,bus_nr=12,bus=pcie.0,id=cxl.1 \ + -device cxl-rp,port=0,bus=cxl.1,id=root_port13,chassis=0,slot=2 \ + -device cxl-type3,bus=root_port13,volatile-memdev=vmem0,id=cxl-vmem0 \ + -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G + Deprecations ------------ diff --git a/docs/system/devices/igb.rst b/docs/system/devices/igb.rst index 71f31cb..50f625f 100644 --- a/docs/system/devices/igb.rst +++ b/docs/system/devices/igb.rst @@ -54,7 +54,7 @@ directory: .. code-block:: shell - meson test qtest-x86_64/qos-test + pyvenv/bin/meson test qtest-x86_64/qos-test ethtool can test register accesses, interrupts, etc. It is automated as an functional test and can be run from the build directory with the following diff --git a/docs/system/devices/net.rst b/docs/system/devices/net.rst index a3efbdc..13199a4 100644 --- a/docs/system/devices/net.rst +++ b/docs/system/devices/net.rst @@ -21,11 +21,17 @@ configure it as if it was a real ethernet card. Linux host ^^^^^^^^^^ -As an example, you can download the ``linux-test-xxx.tar.gz`` archive -and copy the script ``qemu-ifup`` in ``/etc`` and configure properly -``sudo`` so that the command ``ifconfig`` contained in ``qemu-ifup`` can -be executed as root. You must verify that your host kernel supports the -TAP network interfaces: the device ``/dev/net/tun`` must be present. +A distribution will generally provide specific helper scripts when it +packages QEMU. By default these are found at ``/etc/qemu-ifup`` and +``/etc/qemu-ifdown`` and are called appropriately when QEMU wants to +change the network state. + +If QEMU is being run as a non-privileged user you may need properly +configure ``sudo`` so that network commands in the scripts can be +executed as root. + +You must verify that your host kernel supports the TAP network +interfaces: the device ``/dev/net/tun`` must be present. See :ref:`sec_005finvocation` to have examples of command lines using the TAP network interfaces. @@ -73,7 +79,7 @@ those sockets. To allow ping for GID 100 (usually users group):: When using the built-in TFTP server, the router is also the TFTP server. -When using the ``'-netdev user,hostfwd=...'`` option, TCP or UDP +When using the ``'-netdev user,hostfwd=...'`` option, TCP, UDP or UNIX connections can be redirected from the host to the guest. It allows for example to redirect X11, telnet or SSH connections. @@ -85,13 +91,59 @@ passt doesn't require any capability or privilege. passt has better performance than ``-net user``, full IPv6 support and better security as it's a daemon that is not executed in QEMU context. -passt can be connected to QEMU either by using a socket -(``-netdev stream``) or using the vhost-user interface (``-netdev vhost-user``). +passt_ can be used in the same way as the user backend (using ``-net passt``, +``-netdev passt`` or ``-nic passt``) or it can be launched manually and +connected to QEMU either by using a socket (``-netdev stream``) or by using +the vhost-user interface (``-netdev vhost-user``). + +Using ``-netdev stream`` or ``-netdev vhost-user`` will allow the user to +enable functionalities not available through the passt backend interface +(like migration). + See `passt(1)`_ for more details on passt. .. _passt: https://passt.top/ .. _passt(1): https://passt.top/builds/latest/web/passt.1.html +To use the passt backend interface +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +There is no need to start the daemon as QEMU will do it for you. + +By default, passt will be started in the socket-based mode. + +.. parsed-literal:: + |qemu_system| [...OPTIONS...] -nic passt + + (qemu) info network + e1000e.0: index=0,type=nic,model=e1000e,macaddr=52:54:00:12:34:56 + \ #net071: index=0,type=passt,stream,connected to pid 24846 + +.. parsed-literal:: + |qemu_system| [...OPTIONS...] -net nic -net passt,tcp-ports=10001,udp-ports=10001 + + (qemu) info network + hub 0 + \ hub0port1: #net136: index=0,type=passt,stream,connected to pid 25204 + \ hub0port0: e1000e.0: index=0,type=nic,model=e1000e,macaddr=52:54:00:12:34:56 + +.. parsed-literal:: + |qemu_system| [...OPTIONS...] -netdev passt,id=netdev0 -device virtio-net,mac=9a:2b:2c:2d:2e:2f,id=virtio0,netdev=netdev0 + + (qemu) info network + virtio0: index=0,type=nic,model=virtio-net-pci,macaddr=9a:2b:2c:2d:2e:2f + \ netdev0: index=0,type=passt,stream,connected to pid 25428 + +To use the vhost-based interface, add the ``vhost-user=on`` parameter and +select the virtio-net device: + +.. parsed-literal:: + |qemu_system| [...OPTIONS...] -nic passt,model=virtio,vhost-user=on + + (qemu) info network + virtio-net-pci.0: index=0,type=nic,model=virtio-net-pci,macaddr=52:54:00:12:34:56 + \ #net006: index=0,type=passt,vhost-user,connected to pid 25731 + To use socket based passt interface: ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/docs/system/devices/vfio-user.rst b/docs/system/devices/vfio-user.rst new file mode 100644 index 0000000..b6dcaa5 --- /dev/null +++ b/docs/system/devices/vfio-user.rst @@ -0,0 +1,26 @@ +.. SPDX-License-Identifier: GPL-2.0-or-later + +========= +vfio-user +========= + +QEMU includes a ``vfio-user`` client. The ``vfio-user`` specification allows for +implementing (PCI) devices in userspace outside of QEMU; it is similar to +``vhost-user`` in this respect (see :doc:`vhost-user`), but can emulate arbitrary +PCI devices, not just ``virtio``. Whereas ``vfio`` is handled by the host +kernel, ``vfio-user``, while similar in implementation, is handled entirely in +userspace. + +For example, SPDK includes a virtual PCI NVMe controller implementation; by +setting up a ``vfio-user`` UNIX socket between QEMU and SPDK, a VM can send NVMe +I/O to the SPDK process. + +Presuming a suitable ``vfio-user`` server has opened a socket at +``/tmp/vfio-user.sock``, a device can be configured with for example: + +.. code-block:: console + +-device '{"driver": "vfio-user-pci","socket": {"path": "/tmp/vfio-user.sock", "type": "unix"}}' + +See `libvfio-user <https://github.com/nutanix/libvfio-user/>`_ for further +information. diff --git a/docs/system/devices/vhost-user.rst b/docs/system/devices/vhost-user.rst index 35259d8..bddf8df 100644 --- a/docs/system/devices/vhost-user.rst +++ b/docs/system/devices/vhost-user.rst @@ -62,26 +62,20 @@ platform details for what sort of virtio bus to use. The referenced *daemons* are not exhaustive, any conforming backend implementing the device and using the vhost-user protocol should work. -vhost-user-device -^^^^^^^^^^^^^^^^^ +vhost-user-test-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: +The vhost-user-test-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:: - - /* Reason: stop inexperienced users confusing themselves */ - dc->user_creatable = false; - - in ``vhost-user-device.c`` and ``vhost-user-device-pci.c`` file and - rebuilding. + While this is a useful device for development it is not recommended + for production use. vhost-user daemon ================= |