docs: Document virtio PCI -device ioeventfd=on|off

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
This commit is contained in:
Stefan Hajnoczi 2010-12-17 12:01:52 +00:00 committed by Michael S. Tsirkin
parent 25db9ebe15
commit 65d6dcbde8
1 changed files with 7 additions and 1 deletions

View File

@ -97,10 +97,13 @@ The -device argument differs in detail for each kind of drive:
* if=virtio
-device virtio-blk-pci,drive=DRIVE-ID,class=C,vectors=V
-device virtio-blk-pci,drive=DRIVE-ID,class=C,vectors=V,ioeventfd=IOEVENTFD
This lets you control PCI device class and MSI-X vectors.
IOEVENTFD controls whether or not ioeventfd is used for virtqueue notify. It
can be set to on (default) or off.
As for all PCI devices, you can add bus=PCI-BUS,addr=DEVFN to
control the PCI device address.
@ -240,6 +243,9 @@ For PCI devices, you can add bus=PCI-BUS,addr=DEVFN to control the PCI
device address, as usual. The old -net nic provides parameter addr
for that, it is silently ignored when the NIC is not a PCI device.
For virtio-net-pci, you can control whether or not ioeventfd is used for
virtqueue notify by setting ioeventfd= to on or off (default).
-net nic accepts vectors=V for all models, but it's silently ignored
except for virtio-net-pci (model=virtio). With -device, only devices
that support it accept it.