Re: [libvirt] [Qemu-devel] [RFC v2] 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 for the other buses (that don't implement slot enumeration yet); * One slot for each entry from query-hotpluggable-cpus.

+## +# @DeviceSlotInfo: +# +# Information on a slot where devices can be plugged. +# +# @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. +# +# @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 slot becomes full, or if the machine +# was already initialized and the slot doesn't support +# hotplug).

+# @hotpluggable: If true, the slot accepts hotplugged devices. +# +# @props: The arguments that should be given to @device_add if plugging +# a device to this slot.

+{ + SlotListState s = { }; + MachineState *ms = MACHINE(qdev_get_machine()); + MachineClass *mc = MACHINE_GET_CLASS(ms); + + s.machine = ms; + s.next = &s.result; + + /* We build the device slot list from two sources: + * 1) Calling the BusClass::enumerate_slots() method on all buses; + * 2) The return value of MachineClass::query_hotpluggable_cpus() + */ + + + object_child_foreach_recursive(qdev_get_machine(), walk_bus, &s); + if (s.err) { + goto out; + } + + if (mc->query_hotpluggable_cpus) { + HotpluggableCPUList *hcl = mc->query_hotpluggable_cpus(ms); + HotpluggableCPUList *i; + + for (i = hcl; i; i = i->next) { + DeviceSlotInfoList *r = g_new0(DeviceSlotInfoList, 1); + HotpluggableCPU *hc = i->value; + r->value = g_new0(DeviceSlotInfo, 1); + r->value->type = DEVICE_SLOT_TYPE_CPU; + r->value->accepted_device_types = g_new0(strList, 1); + r->value->accepted_device_types->value = g_strdup(hc->type); + r->value->available = !hc->has_qom_path; + /*TODO: should it be always true? */ + r->value->hotpluggable = true;

+ + r->value->u.cpu.props = QAPI_CLONE(CpuInstanceProperties, + hc->props); + *s.next = r; + s.next = & r->next; + } + + qapi_free_HotpluggableCPUList(hcl); + } + +out: + error_propagate(errp, s.err); + return s.result; +} + #define qdev_printf(fmt, ...) monitor_printf(mon, "%*s" fmt, indent, "", ## __VA_ARGS__) static void qbus_print(Monitor *mon, BusState *bus, int indent);