Re: [libvirt] [Qemu-devel] [RFC] qmp: query-device-slots command

This adds a new command to QMP: query-device-slots. It will allow management software to query possible slots where devices can be plugged. This implementation of the command will return: * Multiple PCI slots per bus, in the case of PCI buses; * One slot per bus in the case of the other buses;

* One slot for each entry from query-hotpluggable-cpus. In the example below, I am not sure if the PCIe ports are all supposed to report all slots, but I didn't find any existing field in PCIBus that would help me figure out the actual number of slots in a given PCI bus. Git tree -------- This patch needs the previous query-machines series I am working on. The full tree can be found on the git tree at: git://github.com/ehabkost/qemu-hacks.git work/query-machines-bus-info Example output -------------- The following output was returned by QEMU when running it as: $ qemu-system-x86_64 -machine q35 \ -readconfig docs/q35-chipset.cfg \ -smp 4,maxcpus=8,sockets=2,cores=2,threads=2 { "return": [

] } Signed-off-by: Eduardo Habkost <ehabkost(a)redhat.com&gt; --- qapi-schema.json | 114 +++++++++++++++++++++++++++++++++++++++++++++++++ include/hw/qdev-core.h | 6 +++ hw/core/bus.c | 49 +++++++++++++++++++++ hw/pci/pci.c | 106 +++++++++++++++++++++++++++++++++------------ qdev-monitor.c | 86 ++++++++++++++++++++++++++++++++++--- 5 files changed, 328 insertions(+), 33 deletions(-) diff --git a/qapi-schema.json b/qapi-schema.json index d48ff3f..484d91e 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -3166,6 +3166,120 @@ { 'command': 'closefd', 'data': {'fdname': 'str'} } ## +# @DeviceSlotType: +# +# Type of device slot +# +# @generic: Generic device slot, with no bus-specific information +# @pci: PCI device slot +# @cpu: CPU device slot +## +{ 'enum': 'DeviceSlotType', + 'data': ['generic', 'pci', 'cpu'] } + +## +# @DeviceSlotInfo: +# +# Information on a slot where devices can be plugged. Some buses +# are represented as a single slot that can support multiple devices, +# and some buses have multiple slots that are identified by arguments +# to @device_add.

+# +# @bus: ID of the bus object where the device can be plugged. Optional, +# as some devices don't need a bus to be plugged (e.g. CPUs). +# Can be copied to the "bus" argument to @device_add.

+# +# @type: type of device slot. +# +# @accepted-device-types: List of device types accepted by the slot. +# Any device plugged to the slot should implement +# one of the accepted device types. +# +# @max-devices: #optional maximum number of devices that can be plugged +# to the slot.

+# +# @devices: List of QOM paths for devices that are already plugged. +# +# @available: If false, the slot is not available for plugging any device. +# This value can change at runtime if condition changes +# (e.g. if the device becomes full, or if the machine +# was already initialized and the slot doesn't support +# hotplug). +# +# @hotpluggable: If true, the slot accepts hotplugged devices. +# +# DeviceSlotInfo structs always have a @props member, whose members +# can be directly copied to the arguments to @device_add.

+## +{ 'union': 'DeviceSlotInfo', + 'base': { 'type': 'DeviceSlotType', + 'accepted-device-types': [ 'str' ], + '*max-devices': 'int', 'devices': [ 'str' ], + 'available': 'bool', 'hotpluggable': 'bool' }, + 'discriminator': 'type', + 'data': { 'generic': 'GenericSlotInfo', + 'pci': 'PCISlotInfo', + 'cpu': 'CPUSlotInfo' } } + +## +# @GenericSlotProperties: +## +{ 'struct': 'GenericSlotProperties', + 'data': { 'bus': 'str' } } + + +## +# @GenericSlotInfo: +# +# Generic slot information, with no bus-specific information +## +{ 'struct': 'GenericSlotInfo', + 'data': { 'props': 'GenericSlotProperties' } } + +## +# @PCIDeviceSlotProperties: +# +# Properties that can be set when plugging a PCI device. +# +# @addr: "addr" argument to @device_add. +# +#FIXME: replace @addr with slot and function properties. +## +{ 'struct': 'PCIDeviceSlotProperties', + 'data': { 'bus': 'str', 'addr': 'int' } } + +## +# @PCISlotInfo: +# +# Information on a PCI device slot. +# +# @props: The @device_add arguments that can be used when plugging +# the device. +## +{ 'struct': 'PCISlotInfo', + 'data': { 'props': 'PCIDeviceSlotProperties' } } + +## +# @CPUSlotInfo: +# +# Information on a CPU device slot. +# +# @props: The @device_add arguments that can be used when plugging +# the device. +## +{ 'struct': 'CPUSlotInfo', + 'data': { 'props': 'CpuInstanceProperties' } } + +## +# @query-device-slots: +# +# Return the list of possible slots for plugging devices using +# @device_add. +## +{ 'command': 'query-device-slots', + 'returns': [ 'DeviceSlotInfo' ] } + +## # @MachineBusInfo # # Information about a bus present on a machine.