Re: [libvirt] [PATCH v2 4/4] Documentation/vfio-mediated-device.txt: update for aggregation attribute

On Fri, 20 Jul 2018 10:19:28 +0800 Zhenyu Wang <zhenyuw(a)linux.intel.com&gt; wrote: > Update mdev doc on new aggregration attribute and instances attribute > for mdev. > > Cc: Kirti Wankhede <kwankhede(a)nvidia.com&gt; > Cc: Alex Williamson <alex.williamson(a)redhat.com&gt; > Cc: Kevin Tian <kevin.tian(a)intel.com&gt; > Signed-off-by: Zhenyu Wang <zhenyuw(a)linux.intel.com&gt; > --- > Documentation/vfio-mediated-device.txt | 39 ++++++++++++++++++++++---- > 1 file changed, 33 insertions(+), 6 deletions(-) > > diff --git a/Documentation/vfio-mediated-device.txt b/Documentation/vfio-mediated-device.txt > index c3f69bcaf96e..9ec9495dcbe7 100644 > --- a/Documentation/vfio-mediated-device.txt > +++ b/Documentation/vfio-mediated-device.txt > @@ -211,12 +211,20 @@ Directories and files under the sysfs for Each Physical Device > | | |--- description > | | |--- [devices] > | |--- [<type-id>] > - | |--- create > - | |--- name > - | |--- available_instances > - | |--- device_api > - | |--- description > - | |--- [devices] > + | | |--- create > + | | |--- name > + | | |--- available_instances > + | | |--- device_api > + | | |--- description > + | | |--- [devices] > + | |--- [<type-id>] > + | | |--- create > + | | |--- name > + | | |--- available_instances > + | | |--- device_api > + | | |--- description > + | | |--- <aggregation> > + | | |--- [devices] > > * [mdev_supported_types] > > @@ -260,6 +268,19 @@ Directories and files under the sysfs for Each Physical Device > This attribute should show brief features/description of the type. This is > optional attribute. > > +* <aggregation> > + > + The description is to show feature for one instance of the type. <aggregation> You are talking about "one instance" here. Can this be different for the same type with different physical devices?

> + is an optional attributes to show that [<type-id>]'s instances can be > + aggregated to be assigned for one mdev device. Set number of instances by > + appending "instances=N" parameter for create. Instances number can't exceed > + available_instances number. Without "instances=N" parameter will be default > + one instance to create. Could there be a case where available_instances is n, but aggregation is only supported for a value m < n? If yes, should m be discoverable via the "aggregation" attribute?

> + > +Example:: > + > + # echo "<uuid>,instances=N" > create > + > Directories and Files Under the sysfs for Each mdev Device > ---------------------------------------------------------- > > @@ -268,6 +289,7 @@ Directories and Files Under the sysfs for Each mdev Device > |- [parent phy device] > |--- [$MDEV_UUID] > |--- remove > + |--- instances > |--- mdev_type {link to its type} > |--- vendor-specific-attributes [optional] > > @@ -281,6 +303,11 @@ Example:: > > # echo 1 > /sys/bus/mdev/devices/$mdev_UUID/remove > > +* instances > + > +For aggregation type show number of instances assigned for this mdev. For normal > +type or default will just show one instance. > + > Mediated device Hot plug > ------------------------ >