libvirt/tests/qemuxmlconfdata/q35-pcie-autoadd.xml

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qemu: auto-add pcie-root-port/dmi-to-pci-bridge controllers as needed Previously libvirt would only add pci-bridge devices automatically when an address was requested for a device that required a legacy PCI slot and none was available. This patch expands that support to dmi-to-pci-bridge (which is needed in order to add a pci-bridge on a machine with a pcie-root), and pcie-root-port (which is needed to add a hotpluggable PCIe device). It does *not* automatically add pcie-switch-upstream-ports or pcie-switch-downstream-ports (and currently there are no plans for that). Given the existing code to auto-add pci-bridge devices, automatically adding pcie-root-ports is fairly straightforward. The dmi-to-pci-bridge support is a bit tricky though, for a few reasons: 1) Although the only reason to add a dmi-to-pci-bridge is so that there is a reasonable place to plug in a pci-bridge controller, most of the time it's not the presence of a pci-bridge *in the config* that triggers the requirement to add a dmi-to-pci-bridge. Rather, it is the presence of a legacy-PCI device in the config, which triggers auto-add of a pci-bridge, which triggers auto-add of a dmi-to-pci-bridge (this is handled in virDomainPCIAddressSetGrow() - if there's a request to add a pci-bridge we'll check if there is a suitable bus to plug it into; if not, we first add a dmi-to-pci-bridge). 2) Once there is already a single dmi-to-pci-bridge on the system, there won't be a need for any more, even if it's full, as long as there is a pci-bridge with an open slot - you can also plug pci-bridges into existing pci-bridges. So we have to make sure we don't add a dmi-to-pci-bridge unless there aren't any dmi-to-pci-bridges *or* any pci-bridges. 3) Although it is strongly discouraged, it is legal for a pci-bridge to be directly plugged into pcie-root, and we don't want to auto-add a dmi-to-pci-bridge if there is already a pci-bridge that's been forced directly into pcie-root. Although libvirt will now automatically create a dmi-to-pci-bridge when it's needed, the code still remains for now that forces a dmi-to-pci-bridge on all domains with pcie-root (in qemuDomainDefAddDefaultDevices()). That will be removed in a future patch. For now, the pcie-root-ports are added one to a slot, which is a bit wasteful and means it will fail after 31 total PCIe devices (30 if there are also some PCI devices), but helps keep the changeset down for this patch. A future patch will have 8 pcie-root-ports sharing the functions on a single slot.
2016-09-19 18:38:47 +00:00
<domain type='qemu'>
<name>q35-test</name>
<uuid>11dbdcdd-4c3b-482b-8903-9bdb8c0a2774</uuid>
<memory unit='KiB'>2097152</memory>
<currentMemory unit='KiB'>2097152</currentMemory>
<vcpu placement='static' cpuset='0-1'>2</vcpu>
<os>
<type arch='x86_64' machine='q35'>hvm</type>
<boot dev='hd'/>
</os>
<clock offset='utc'/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>destroy</on_crash>
<devices>
<emulator>/usr/bin/qemu-system-x86_64</emulator>
qemu: auto-add pcie-root-port/dmi-to-pci-bridge controllers as needed Previously libvirt would only add pci-bridge devices automatically when an address was requested for a device that required a legacy PCI slot and none was available. This patch expands that support to dmi-to-pci-bridge (which is needed in order to add a pci-bridge on a machine with a pcie-root), and pcie-root-port (which is needed to add a hotpluggable PCIe device). It does *not* automatically add pcie-switch-upstream-ports or pcie-switch-downstream-ports (and currently there are no plans for that). Given the existing code to auto-add pci-bridge devices, automatically adding pcie-root-ports is fairly straightforward. The dmi-to-pci-bridge support is a bit tricky though, for a few reasons: 1) Although the only reason to add a dmi-to-pci-bridge is so that there is a reasonable place to plug in a pci-bridge controller, most of the time it's not the presence of a pci-bridge *in the config* that triggers the requirement to add a dmi-to-pci-bridge. Rather, it is the presence of a legacy-PCI device in the config, which triggers auto-add of a pci-bridge, which triggers auto-add of a dmi-to-pci-bridge (this is handled in virDomainPCIAddressSetGrow() - if there's a request to add a pci-bridge we'll check if there is a suitable bus to plug it into; if not, we first add a dmi-to-pci-bridge). 2) Once there is already a single dmi-to-pci-bridge on the system, there won't be a need for any more, even if it's full, as long as there is a pci-bridge with an open slot - you can also plug pci-bridges into existing pci-bridges. So we have to make sure we don't add a dmi-to-pci-bridge unless there aren't any dmi-to-pci-bridges *or* any pci-bridges. 3) Although it is strongly discouraged, it is legal for a pci-bridge to be directly plugged into pcie-root, and we don't want to auto-add a dmi-to-pci-bridge if there is already a pci-bridge that's been forced directly into pcie-root. Although libvirt will now automatically create a dmi-to-pci-bridge when it's needed, the code still remains for now that forces a dmi-to-pci-bridge on all domains with pcie-root (in qemuDomainDefAddDefaultDevices()). That will be removed in a future patch. For now, the pcie-root-ports are added one to a slot, which is a bit wasteful and means it will fail after 31 total PCIe devices (30 if there are also some PCI devices), but helps keep the changeset down for this patch. A future patch will have 8 pcie-root-ports sharing the functions on a single slot.
2016-09-19 18:38:47 +00:00
<controller type='virtio-serial'/>
<controller type='scsi' model='virtio-scsi'/>
<controller type='usb' model='nec-xhci'/>
<disk type='block' device='disk'>
<source dev='/dev/HostVG/QEMUGuest1'/>
<target dev='vdb' bus='virtio'/>
</disk>
<filesystem type='mount'>
<source dir='/export/to/guest'/>
<target dir='/import/from/host'/>
</filesystem>
<video>
<model type='virtio'/>
</video>
<interface type='user'>
<mac address='00:11:22:33:44:55'/>
<model type='virtio'/>
</interface>
<interface type='user'>
<mac address='00:11:22:33:44:66'/>
<model type='e1000e'/>
</interface>
<memballoon model='virtio'/>
<rng model='virtio'>
<rate bytes='123' period='1234'/>
<backend model='random'>/dev/urandom</backend>
</rng>
<input type='passthrough' bus='virtio'>
<source evdev='/dev/input/event1234'/>
</input>
<input type='mouse' bus='virtio'/>
<input type='keyboard' bus='virtio'/>
<input type='tablet' bus='virtio'/>
</devices>
</domain>