From d2321d31ff98b75b652c2b1594f00a4cfd48102a Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Mon, 16 Sep 2019 16:07:16 +0800 Subject: [PATCH] qdev/machine: Introduce hotplug_allowed hook Introduce this new per-machine hook to give any machine class a chance to do a sanity check on the to-be-hotplugged device as a sanity test. This will be used for x86 to try to detect some illegal configuration of devices, e.g., possible conflictions between vfio-pci and x86 vIOMMU. Reviewed-by: Eric Auger Signed-off-by: Peter Xu Message-Id: <20190916080718.3299-3-peterx@redhat.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/core/qdev.c | 17 +++++++++++++++++ include/hw/boards.h | 9 +++++++++ include/hw/qdev-core.h | 1 + qdev-monitor.c | 7 +++++++ 4 files changed, 34 insertions(+) diff --git a/hw/core/qdev.c b/hw/core/qdev.c index 60d66c2f39..cbad6c1d55 100644 --- a/hw/core/qdev.c +++ b/hw/core/qdev.c @@ -237,6 +237,23 @@ HotplugHandler *qdev_get_machine_hotplug_handler(DeviceState *dev) return NULL; } +bool qdev_hotplug_allowed(DeviceState *dev, Error **errp) +{ + MachineState *machine; + MachineClass *mc; + Object *m_obj = qdev_get_machine(); + + if (object_dynamic_cast(m_obj, TYPE_MACHINE)) { + machine = MACHINE(m_obj); + mc = MACHINE_GET_CLASS(machine); + if (mc->hotplug_allowed) { + return mc->hotplug_allowed(machine, dev, errp); + } + } + + return true; +} + HotplugHandler *qdev_get_bus_hotplug_handler(DeviceState *dev) { if (dev->parent_bus) { diff --git a/include/hw/boards.h b/include/hw/boards.h index 2289536e48..be18a5c032 100644 --- a/include/hw/boards.h +++ b/include/hw/boards.h @@ -166,6 +166,13 @@ typedef struct { * The function pointer to hook different machine specific functions for * parsing "smp-opts" from QemuOpts to MachineState::CpuTopology and more * machine specific topology fields, such as smp_dies for PCMachine. + * @hotplug_allowed: + * If the hook is provided, then it'll be called for each device + * hotplug to check whether the device hotplug is allowed. Return + * true to grant allowance or false to reject the hotplug. When + * false is returned, an error must be set to show the reason of + * the rejection. If the hook is not provided, all hotplug will be + * allowed. */ struct MachineClass { /*< private >*/ @@ -224,6 +231,8 @@ struct MachineClass { HotplugHandler *(*get_hotplug_handler)(MachineState *machine, DeviceState *dev); + bool (*hotplug_allowed)(MachineState *state, DeviceState *dev, + Error **errp); CpuInstanceProperties (*cpu_index_to_instance_props)(MachineState *machine, unsigned cpu_index); const CPUArchIdList *(*possible_cpu_arch_ids)(MachineState *machine); diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h index de70b7a19a..aa123f88cb 100644 --- a/include/hw/qdev-core.h +++ b/include/hw/qdev-core.h @@ -280,6 +280,7 @@ void qdev_set_legacy_instance_id(DeviceState *dev, int alias_id, int required_for_version); HotplugHandler *qdev_get_bus_hotplug_handler(DeviceState *dev); HotplugHandler *qdev_get_machine_hotplug_handler(DeviceState *dev); +bool qdev_hotplug_allowed(DeviceState *dev, Error **errp); /** * qdev_get_hotplug_handler: Get handler responsible for device wiring * diff --git a/qdev-monitor.c b/qdev-monitor.c index 8fe5c2cad2..148df9cacf 100644 --- a/qdev-monitor.c +++ b/qdev-monitor.c @@ -615,6 +615,13 @@ DeviceState *qdev_device_add(QemuOpts *opts, Error **errp) /* create device */ dev = DEVICE(object_new(driver)); + /* Check whether the hotplug is allowed by the machine */ + if (qdev_hotplug && !qdev_hotplug_allowed(dev, &err)) { + /* Error must be set in the machine hook */ + assert(err); + goto err_del_dev; + } + if (bus) { qdev_set_parent_bus(dev, bus); } else if (qdev_hotplug && !qdev_get_machine_hotplug_handler(dev)) { -- GitLab