diff options
Diffstat (limited to 'docs/system/devices')
| -rw-r--r-- | docs/system/devices/cxl.rst | 18 | ||||
| -rw-r--r-- | docs/system/devices/vfio-user.rst | 26 |
2 files changed, 35 insertions, 9 deletions
diff --git a/docs/system/devices/cxl.rst b/docs/system/devices/cxl.rst index 882b036..e307caf 100644 --- a/docs/system/devices/cxl.rst +++ b/docs/system/devices/cxl.rst @@ -308,7 +308,7 @@ A very simple setup with just one directly attached CXL Type 3 Persistent Memory -object memory-backend-file,id=cxl-lsa1,share=on,mem-path=/tmp/lsa.raw,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,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0 \ + -device cxl-type3,bus=root_port13,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0,sn=0x1 \ -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.size=4G A very simple setup with just one directly attached CXL Type 3 Volatile Memory device:: @@ -349,13 +349,13 @@ the CXL Type3 device directly attached (no switches).:: -device pxb-cxl,bus_nr=12,bus=pcie.0,id=cxl.1 \ -device pxb-cxl,bus_nr=222,bus=pcie.0,id=cxl.2 \ -device cxl-rp,port=0,bus=cxl.1,id=root_port13,chassis=0,slot=2 \ - -device cxl-type3,bus=root_port13,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0 \ + -device cxl-type3,bus=root_port13,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem0,sn=0x1 \ -device cxl-rp,port=1,bus=cxl.1,id=root_port14,chassis=0,slot=3 \ - -device cxl-type3,bus=root_port14,persistent-memdev=cxl-mem2,lsa=cxl-lsa2,id=cxl-pmem1 \ + -device cxl-type3,bus=root_port14,persistent-memdev=cxl-mem2,lsa=cxl-lsa2,id=cxl-pmem1,sn=0x2 \ -device cxl-rp,port=0,bus=cxl.2,id=root_port15,chassis=0,slot=5 \ - -device cxl-type3,bus=root_port15,persistent-memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem2 \ + -device cxl-type3,bus=root_port15,persistent-memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem2,sn=0x3 \ -device cxl-rp,port=1,bus=cxl.2,id=root_port16,chassis=0,slot=6 \ - -device cxl-type3,bus=root_port16,persistent-memdev=cxl-mem4,lsa=cxl-lsa4,id=cxl-pmem3 \ + -device cxl-type3,bus=root_port16,persistent-memdev=cxl-mem4,lsa=cxl-lsa4,id=cxl-pmem3,sn=0x4 \ -M cxl-fmw.0.targets.0=cxl.1,cxl-fmw.0.targets.1=cxl.2,cxl-fmw.0.size=4G,cxl-fmw.0.interleave-granularity=8k An example of 4 devices below a switch suitable for 1, 2 or 4 way interleave:: @@ -375,13 +375,13 @@ An example of 4 devices below a switch suitable for 1, 2 or 4 way interleave:: -device cxl-rp,port=1,bus=cxl.1,id=root_port1,chassis=0,slot=1 \ -device cxl-upstream,bus=root_port0,id=us0 \ -device cxl-downstream,port=0,bus=us0,id=swport0,chassis=0,slot=4 \ - -device cxl-type3,bus=swport0,persistent-memdev=cxl-mem0,lsa=cxl-lsa0,id=cxl-pmem0 \ + -device cxl-type3,bus=swport0,persistent-memdev=cxl-mem0,lsa=cxl-lsa0,id=cxl-pmem0,sn=0x1 \ -device cxl-downstream,port=1,bus=us0,id=swport1,chassis=0,slot=5 \ - -device cxl-type3,bus=swport1,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem1 \ + -device cxl-type3,bus=swport1,persistent-memdev=cxl-mem1,lsa=cxl-lsa1,id=cxl-pmem1,sn=0x2 \ -device cxl-downstream,port=2,bus=us0,id=swport2,chassis=0,slot=6 \ - -device cxl-type3,bus=swport2,persistent-memdev=cxl-mem2,lsa=cxl-lsa2,id=cxl-pmem2 \ + -device cxl-type3,bus=swport2,persistent-memdev=cxl-mem2,lsa=cxl-lsa2,id=cxl-pmem2,sn=0x3 \ -device cxl-downstream,port=3,bus=us0,id=swport3,chassis=0,slot=7 \ - -device cxl-type3,bus=swport3,persistent-memdev=cxl-mem3,lsa=cxl-lsa3,id=cxl-pmem3 \ + -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 Deprecations 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. |