The downstream ports of an x3130-upstream switch can each have one of
these plugged into them (and that is the only place they can be
connected). Each xio3130-downstream provides a single PCIe port that
can have PCI or PCIe devices hotplugged into it. Apparently an entire
set of x3130-upstream + several xio3130-downstreams can be hotplugged
as a unit, but it's not clear to me yet how that would be done, since
qemu only allows attaching a single device at a time.
This device will be used to implement the
"pcie-switch-downstream-port" model of pci controller.
This is the upstream part of a PCIe switch. It connects to a PCIe port
(but not PCI) on the upstream side, and can have up to 31
xio3130-downstream controllers (but no other types of devices)
connected to its downstream side.
This device will be used to implement the "pcie-switch-upstream-port"
model of pci controller.
This is a PCIE "root port". It connects only to a port of the
integrated pcie.0 bus of a Q35 machine (can't be hotplugged), and
provides a single PCIe port that can have PCI or PCIe devices
hotplugged into it.
This device will be used to implement the "pcie-root-port" model of
pci controller.
https://bugzilla.redhat.com/show_bug.cgi?id=998813
Implementation is pretty straight-forward. Of course, not all qemus
out there supports the device, so new capability is introduced and
checked prior each use of the device.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Ivshmem is supported by QEMU since 0.13 release.
Signed-off-by: Maxime Leroy <maxime.leroy@6wind.com>
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Quite a long time ago, (apparently between qemu 0.12 and 0.13) qemu
quietly began supporting the optional specification of a domain in the
host-side address of all pci passthrough commands (by simply
prepending it to the bus:slot.function format, as
"dddd:bb:ss.f"). Since machines with multiple PCI domains are very
rare, this never came up in practice, so libvirt was never updated to
support it.
This patch takes the first step to supporting specification of a non-0
domain in the host-side address of PCI devices being assigned to a
domain, by adding a capability bit to indicate support
"QEMU_CAPS_HOST_PCI_MULTIDOMAIN", and detect it. Since this support
was added in a version prior to the minimum version required for
QMP-style capabilities detection, the capability is always enabled for
any qemu that uses QMP for capabilities detection. For older qemus,
the only clue that a domain can be specified in the host pci address
is the presence of the string "[seg:]" in the help string for
-pcidevice. (Ironically, libvirt will not be modified to support
specification of domain for -pcidevice, since any qemu new enough for
us to care about also supports "-device pci-assign" or "-device
vfio-pci", which are greatly preferred).
