| Message ID | 20240429101623.1992943-4-vsementsov@yandex-team.ru (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vhost-user-blk: live resize additional APIs | expand |
Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> writes: > Add command to sync config from vhost-user backend to the device. It > may be helpful when VHOST_USER_SLAVE_CONFIG_CHANGE_MSG failed or not > triggered interrupt to the guest or just not available (not supported > by vhost-user server). > > Command result is racy if allow it during migration. Let's allow the > sync only in RUNNING state. > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> > --- > hw/block/vhost-user-blk.c | 1 + > hw/virtio/virtio-pci.c | 9 ++++++++ > include/hw/qdev-core.h | 3 +++ > qapi/qdev.json | 23 +++++++++++++++++++ > system/qdev-monitor.c | 48 +++++++++++++++++++++++++++++++++++++++ > 5 files changed, 84 insertions(+) > > diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c > index 091d2c6acf..2f301f380c 100644 > --- a/hw/block/vhost-user-blk.c > +++ b/hw/block/vhost-user-blk.c > @@ -588,6 +588,7 @@ static void vhost_user_blk_class_init(ObjectClass *klass, void *data) > > device_class_set_props(dc, vhost_user_blk_properties); > dc->vmsd = &vmstate_vhost_user_blk; > + dc->sync_config = vhost_user_blk_sync_config; > set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); > vdc->realize = vhost_user_blk_device_realize; > vdc->unrealize = vhost_user_blk_device_unrealize; > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index b1d02f4b3d..0d91e8b5dc 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -2351,6 +2351,14 @@ static void virtio_pci_dc_realize(DeviceState *qdev, Error **errp) > vpciklass->parent_dc_realize(qdev, errp); > } > > +static int virtio_pci_sync_config(DeviceState *dev, Error **errp) > +{ > + VirtIOPCIProxy *proxy = VIRTIO_PCI(dev); > + VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > + > + return qdev_sync_config(DEVICE(vdev), errp); > +} > + > static void virtio_pci_class_init(ObjectClass *klass, void *data) > { > DeviceClass *dc = DEVICE_CLASS(klass); > @@ -2367,6 +2375,7 @@ static void virtio_pci_class_init(ObjectClass *klass, void *data) > device_class_set_parent_realize(dc, virtio_pci_dc_realize, > &vpciklass->parent_dc_realize); > rc->phases.hold = virtio_pci_bus_reset_hold; > + dc->sync_config = virtio_pci_sync_config; > } > > static const TypeInfo virtio_pci_info = { > diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h > index 9228e96c87..87135bdcdf 100644 > --- a/include/hw/qdev-core.h > +++ b/include/hw/qdev-core.h > @@ -95,6 +95,7 @@ typedef void (*DeviceUnrealize)(DeviceState *dev); > typedef void (*DeviceReset)(DeviceState *dev); > typedef void (*BusRealize)(BusState *bus, Error **errp); > typedef void (*BusUnrealize)(BusState *bus); > +typedef int (*DeviceSyncConfig)(DeviceState *dev, Error **errp); > > /** > * struct DeviceClass - The base class for all devices. > @@ -162,6 +163,7 @@ struct DeviceClass { > DeviceReset reset; > DeviceRealize realize; > DeviceUnrealize unrealize; > + DeviceSyncConfig sync_config; > > /** > * @vmsd: device state serialisation description for > @@ -546,6 +548,7 @@ bool qdev_hotplug_allowed(DeviceState *dev, Error **errp); > */ > HotplugHandler *qdev_get_hotplug_handler(DeviceState *dev); > void qdev_unplug(DeviceState *dev, Error **errp); > +int qdev_sync_config(DeviceState *dev, Error **errp); > void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev, > DeviceState *dev, Error **errp); > void qdev_machine_creation_done(void); > diff --git a/qapi/qdev.json b/qapi/qdev.json > index facaa0bc6a..fc5e125a45 100644 > --- a/qapi/qdev.json > +++ b/qapi/qdev.json > @@ -161,3 +161,26 @@ > ## > { 'event': 'DEVICE_UNPLUG_GUEST_ERROR', > 'data': { '*device': 'str', 'path': 'str' } } > + > +## > +# @device-sync-config: > +# > +# Synchronize device configuration from host to guest part. First, > +# copy the configuration from the host part (backend) to the guest > +# part (frontend). Then notify guest software that device > +# configuration changed. Blank line here, please. > +# The command may be used to notify the guest about block device > +# capcity change. Currently only vhost-user-blk device supports > +# this. > +# > +# @id: the device's ID or QOM path > +# > +# Features: > +# > +# @unstable: The command is experimental. > +# > +# Since: 9.1 > +## > +{ 'command': 'device-sync-config', > + 'features': [ 'unstable' ], > + 'data': {'id': 'str'} } > diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c > index 264978aa40..47bfc0506e 100644 > --- a/system/qdev-monitor.c > +++ b/system/qdev-monitor.c > @@ -23,6 +23,7 @@ > #include "monitor/monitor.h" > #include "monitor/qdev.h" > #include "sysemu/arch_init.h" > +#include "sysemu/runstate.h" > #include "qapi/error.h" > #include "qapi/qapi-commands-qdev.h" > #include "qapi/qmp/dispatch.h" > @@ -971,6 +972,53 @@ void qmp_device_del(const char *id, Error **errp) > } > } > > +int qdev_sync_config(DeviceState *dev, Error **errp) > +{ > + DeviceClass *dc = DEVICE_GET_CLASS(dev); > + > + if (!dc->sync_config) { > + error_setg(errp, "device-sync-config is not supported for '%s'", > + object_get_typename(OBJECT(dev))); > + return -ENOTSUP; > + } > + > + return dc->sync_config(dev, errp); > +} > + > +void qmp_device_sync_config(const char *id, Error **errp) > +{ > + DeviceState *dev; > + > + /* > + * During migration there is a race between syncing`configuration and > + * migrating it (if migrate first, that target would get outdated version), > + * so let's just not allow it. Wrap comment lines around column 70 for legibility, please. > + * > + * Moreover, let's not rely on setting up interrupts in paused > + * state, which may be a part of migration process. We discussed this in review of v3. You wanted to check whether the problem is real. Is it? > + */ > + > + if (migration_is_running()) { > + error_setg(errp, "Config synchronization is not allowed " > + "during migration"); > + return; > + } > + > + if (!runstate_is_running()) { > + error_setg(errp, "Config synchronization allowed only in '%s' state, " Suggest a line break after errp, > + "current state is '%s'", RunState_str(RUN_STATE_RUNNING), > + RunState_str(runstate_get())); > + return; > + } > + > + dev = find_device_state(id, true, errp); > + if (!dev) { > + return; > + } > + > + qdev_sync_config(dev, errp); > +} > + > void hmp_device_add(Monitor *mon, const QDict *qdict) > { > Error *err = NULL;
On 30.04.24 11:19, Markus Armbruster wrote: > Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> writes: > >> Add command to sync config from vhost-user backend to the device. It >> may be helpful when VHOST_USER_SLAVE_CONFIG_CHANGE_MSG failed or not >> triggered interrupt to the guest or just not available (not supported >> by vhost-user server). >> >> Command result is racy if allow it during migration. Let's allow the >> sync only in RUNNING state. >> >> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> >> --- >> hw/block/vhost-user-blk.c | 1 + >> hw/virtio/virtio-pci.c | 9 ++++++++ >> include/hw/qdev-core.h | 3 +++ >> qapi/qdev.json | 23 +++++++++++++++++++ >> system/qdev-monitor.c | 48 +++++++++++++++++++++++++++++++++++++++ >> 5 files changed, 84 insertions(+) >> >> diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c >> index 091d2c6acf..2f301f380c 100644 >> --- a/hw/block/vhost-user-blk.c >> +++ b/hw/block/vhost-user-blk.c >> @@ -588,6 +588,7 @@ static void vhost_user_blk_class_init(ObjectClass *klass, void *data) >> >> device_class_set_props(dc, vhost_user_blk_properties); >> dc->vmsd = &vmstate_vhost_user_blk; >> + dc->sync_config = vhost_user_blk_sync_config; >> set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); >> vdc->realize = vhost_user_blk_device_realize; >> vdc->unrealize = vhost_user_blk_device_unrealize; >> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c >> index b1d02f4b3d..0d91e8b5dc 100644 >> --- a/hw/virtio/virtio-pci.c >> +++ b/hw/virtio/virtio-pci.c >> @@ -2351,6 +2351,14 @@ static void virtio_pci_dc_realize(DeviceState *qdev, Error **errp) >> vpciklass->parent_dc_realize(qdev, errp); >> } >> >> +static int virtio_pci_sync_config(DeviceState *dev, Error **errp) >> +{ >> + VirtIOPCIProxy *proxy = VIRTIO_PCI(dev); >> + VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); >> + >> + return qdev_sync_config(DEVICE(vdev), errp); >> +} >> + >> static void virtio_pci_class_init(ObjectClass *klass, void *data) >> { >> DeviceClass *dc = DEVICE_CLASS(klass); >> @@ -2367,6 +2375,7 @@ static void virtio_pci_class_init(ObjectClass *klass, void *data) >> device_class_set_parent_realize(dc, virtio_pci_dc_realize, >> &vpciklass->parent_dc_realize); >> rc->phases.hold = virtio_pci_bus_reset_hold; >> + dc->sync_config = virtio_pci_sync_config; >> } >> >> static const TypeInfo virtio_pci_info = { >> diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h >> index 9228e96c87..87135bdcdf 100644 >> --- a/include/hw/qdev-core.h >> +++ b/include/hw/qdev-core.h >> @@ -95,6 +95,7 @@ typedef void (*DeviceUnrealize)(DeviceState *dev); >> typedef void (*DeviceReset)(DeviceState *dev); >> typedef void (*BusRealize)(BusState *bus, Error **errp); >> typedef void (*BusUnrealize)(BusState *bus); >> +typedef int (*DeviceSyncConfig)(DeviceState *dev, Error **errp); >> >> /** >> * struct DeviceClass - The base class for all devices. >> @@ -162,6 +163,7 @@ struct DeviceClass { >> DeviceReset reset; >> DeviceRealize realize; >> DeviceUnrealize unrealize; >> + DeviceSyncConfig sync_config; >> >> /** >> * @vmsd: device state serialisation description for >> @@ -546,6 +548,7 @@ bool qdev_hotplug_allowed(DeviceState *dev, Error **errp); >> */ >> HotplugHandler *qdev_get_hotplug_handler(DeviceState *dev); >> void qdev_unplug(DeviceState *dev, Error **errp); >> +int qdev_sync_config(DeviceState *dev, Error **errp); >> void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev, >> DeviceState *dev, Error **errp); >> void qdev_machine_creation_done(void); >> diff --git a/qapi/qdev.json b/qapi/qdev.json >> index facaa0bc6a..fc5e125a45 100644 >> --- a/qapi/qdev.json >> +++ b/qapi/qdev.json >> @@ -161,3 +161,26 @@ >> ## >> { 'event': 'DEVICE_UNPLUG_GUEST_ERROR', >> 'data': { '*device': 'str', 'path': 'str' } } >> + >> +## >> +# @device-sync-config: >> +# >> +# Synchronize device configuration from host to guest part. First, >> +# copy the configuration from the host part (backend) to the guest >> +# part (frontend). Then notify guest software that device >> +# configuration changed. > > Blank line here, please. > >> +# The command may be used to notify the guest about block device >> +# capcity change. Currently only vhost-user-blk device supports >> +# this. >> +# >> +# @id: the device's ID or QOM path >> +# >> +# Features: >> +# >> +# @unstable: The command is experimental. >> +# >> +# Since: 9.1 >> +## >> +{ 'command': 'device-sync-config', >> + 'features': [ 'unstable' ], >> + 'data': {'id': 'str'} } >> diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c >> index 264978aa40..47bfc0506e 100644 >> --- a/system/qdev-monitor.c >> +++ b/system/qdev-monitor.c >> @@ -23,6 +23,7 @@ >> #include "monitor/monitor.h" >> #include "monitor/qdev.h" >> #include "sysemu/arch_init.h" >> +#include "sysemu/runstate.h" >> #include "qapi/error.h" >> #include "qapi/qapi-commands-qdev.h" >> #include "qapi/qmp/dispatch.h" >> @@ -971,6 +972,53 @@ void qmp_device_del(const char *id, Error **errp) >> } >> } >> >> +int qdev_sync_config(DeviceState *dev, Error **errp) >> +{ >> + DeviceClass *dc = DEVICE_GET_CLASS(dev); >> + >> + if (!dc->sync_config) { >> + error_setg(errp, "device-sync-config is not supported for '%s'", >> + object_get_typename(OBJECT(dev))); >> + return -ENOTSUP; >> + } >> + >> + return dc->sync_config(dev, errp); >> +} >> + >> +void qmp_device_sync_config(const char *id, Error **errp) >> +{ >> + DeviceState *dev; >> + >> + /* >> + * During migration there is a race between syncing`configuration and >> + * migrating it (if migrate first, that target would get outdated version), >> + * so let's just not allow it. > > Wrap comment lines around column 70 for legibility, please. > >> + * >> + * Moreover, let's not rely on setting up interrupts in paused >> + * state, which may be a part of migration process. > > We discussed this in review of v3. You wanted to check whether the > problem is real. Is it? We discussed it later than I've sent v4 :) No, I didn't check yet. > >> + */ >> + >> + if (migration_is_running()) { >> + error_setg(errp, "Config synchronization is not allowed " >> + "during migration"); >> + return; >> + } >> + >> + if (!runstate_is_running()) { >> + error_setg(errp, "Config synchronization allowed only in '%s' state, " > > Suggest a line break after errp, > >> + "current state is '%s'", RunState_str(RUN_STATE_RUNNING), >> + RunState_str(runstate_get())); >> + return; >> + } >> + >> + dev = find_device_state(id, true, errp); >> + if (!dev) { >> + return; >> + } >> + >> + qdev_sync_config(dev, errp); >> +} >> + >> void hmp_device_add(Monitor *mon, const QDict *qdict) >> { >> Error *err = NULL; >
On 30.04.24 11:31, Vladimir Sementsov-Ogievskiy wrote: > On 30.04.24 11:19, Markus Armbruster wrote: >> Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> writes: >> >>> Add command to sync config from vhost-user backend to the device. It >>> may be helpful when VHOST_USER_SLAVE_CONFIG_CHANGE_MSG failed or not >>> triggered interrupt to the guest or just not available (not supported >>> by vhost-user server). >>> >>> Command result is racy if allow it during migration. Let's allow the >>> sync only in RUNNING state. >>> >>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> >>> --- >>> hw/block/vhost-user-blk.c | 1 + >>> hw/virtio/virtio-pci.c | 9 ++++++++ >>> include/hw/qdev-core.h | 3 +++ >>> qapi/qdev.json | 23 +++++++++++++++++++ >>> system/qdev-monitor.c | 48 +++++++++++++++++++++++++++++++++++++++ >>> 5 files changed, 84 insertions(+) >>> >>> diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c >>> index 091d2c6acf..2f301f380c 100644 >>> --- a/hw/block/vhost-user-blk.c >>> +++ b/hw/block/vhost-user-blk.c >>> @@ -588,6 +588,7 @@ static void vhost_user_blk_class_init(ObjectClass *klass, void *data) >>> device_class_set_props(dc, vhost_user_blk_properties); >>> dc->vmsd = &vmstate_vhost_user_blk; >>> + dc->sync_config = vhost_user_blk_sync_config; >>> set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); >>> vdc->realize = vhost_user_blk_device_realize; >>> vdc->unrealize = vhost_user_blk_device_unrealize; >>> diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c >>> index b1d02f4b3d..0d91e8b5dc 100644 >>> --- a/hw/virtio/virtio-pci.c >>> +++ b/hw/virtio/virtio-pci.c >>> @@ -2351,6 +2351,14 @@ static void virtio_pci_dc_realize(DeviceState *qdev, Error **errp) >>> vpciklass->parent_dc_realize(qdev, errp); >>> } >>> +static int virtio_pci_sync_config(DeviceState *dev, Error **errp) >>> +{ >>> + VirtIOPCIProxy *proxy = VIRTIO_PCI(dev); >>> + VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); >>> + >>> + return qdev_sync_config(DEVICE(vdev), errp); >>> +} >>> + >>> static void virtio_pci_class_init(ObjectClass *klass, void *data) >>> { >>> DeviceClass *dc = DEVICE_CLASS(klass); >>> @@ -2367,6 +2375,7 @@ static void virtio_pci_class_init(ObjectClass *klass, void *data) >>> device_class_set_parent_realize(dc, virtio_pci_dc_realize, >>> &vpciklass->parent_dc_realize); >>> rc->phases.hold = virtio_pci_bus_reset_hold; >>> + dc->sync_config = virtio_pci_sync_config; >>> } >>> static const TypeInfo virtio_pci_info = { >>> diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h >>> index 9228e96c87..87135bdcdf 100644 >>> --- a/include/hw/qdev-core.h >>> +++ b/include/hw/qdev-core.h >>> @@ -95,6 +95,7 @@ typedef void (*DeviceUnrealize)(DeviceState *dev); >>> typedef void (*DeviceReset)(DeviceState *dev); >>> typedef void (*BusRealize)(BusState *bus, Error **errp); >>> typedef void (*BusUnrealize)(BusState *bus); >>> +typedef int (*DeviceSyncConfig)(DeviceState *dev, Error **errp); >>> /** >>> * struct DeviceClass - The base class for all devices. >>> @@ -162,6 +163,7 @@ struct DeviceClass { >>> DeviceReset reset; >>> DeviceRealize realize; >>> DeviceUnrealize unrealize; >>> + DeviceSyncConfig sync_config; >>> /** >>> * @vmsd: device state serialisation description for >>> @@ -546,6 +548,7 @@ bool qdev_hotplug_allowed(DeviceState *dev, Error **errp); >>> */ >>> HotplugHandler *qdev_get_hotplug_handler(DeviceState *dev); >>> void qdev_unplug(DeviceState *dev, Error **errp); >>> +int qdev_sync_config(DeviceState *dev, Error **errp); >>> void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev, >>> DeviceState *dev, Error **errp); >>> void qdev_machine_creation_done(void); >>> diff --git a/qapi/qdev.json b/qapi/qdev.json >>> index facaa0bc6a..fc5e125a45 100644 >>> --- a/qapi/qdev.json >>> +++ b/qapi/qdev.json >>> @@ -161,3 +161,26 @@ >>> ## >>> { 'event': 'DEVICE_UNPLUG_GUEST_ERROR', >>> 'data': { '*device': 'str', 'path': 'str' } } >>> + >>> +## >>> +# @device-sync-config: >>> +# >>> +# Synchronize device configuration from host to guest part. First, >>> +# copy the configuration from the host part (backend) to the guest >>> +# part (frontend). Then notify guest software that device >>> +# configuration changed. >> >> Blank line here, please. >> >>> +# The command may be used to notify the guest about block device >>> +# capcity change. Currently only vhost-user-blk device supports >>> +# this. >>> +# >>> +# @id: the device's ID or QOM path >>> +# >>> +# Features: >>> +# >>> +# @unstable: The command is experimental. >>> +# >>> +# Since: 9.1 >>> +## >>> +{ 'command': 'device-sync-config', >>> + 'features': [ 'unstable' ], >>> + 'data': {'id': 'str'} } >>> diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c >>> index 264978aa40..47bfc0506e 100644 >>> --- a/system/qdev-monitor.c >>> +++ b/system/qdev-monitor.c >>> @@ -23,6 +23,7 @@ >>> #include "monitor/monitor.h" >>> #include "monitor/qdev.h" >>> #include "sysemu/arch_init.h" >>> +#include "sysemu/runstate.h" >>> #include "qapi/error.h" >>> #include "qapi/qapi-commands-qdev.h" >>> #include "qapi/qmp/dispatch.h" >>> @@ -971,6 +972,53 @@ void qmp_device_del(const char *id, Error **errp) >>> } >>> } >>> +int qdev_sync_config(DeviceState *dev, Error **errp) >>> +{ >>> + DeviceClass *dc = DEVICE_GET_CLASS(dev); >>> + >>> + if (!dc->sync_config) { >>> + error_setg(errp, "device-sync-config is not supported for '%s'", >>> + object_get_typename(OBJECT(dev))); >>> + return -ENOTSUP; >>> + } >>> + >>> + return dc->sync_config(dev, errp); >>> +} >>> + >>> +void qmp_device_sync_config(const char *id, Error **errp) >>> +{ >>> + DeviceState *dev; >>> + >>> + /* >>> + * During migration there is a race between syncing`configuration and >>> + * migrating it (if migrate first, that target would get outdated version), >>> + * so let's just not allow it. >> >> Wrap comment lines around column 70 for legibility, please. >> >>> + * >>> + * Moreover, let's not rely on setting up interrupts in paused >>> + * state, which may be a part of migration process. >> >> We discussed this in review of v3. You wanted to check whether the >> problem is real. Is it? > > We discussed it later than I've sent v4 :) No, I didn't check yet. Checked. Seems this works (in scheme pause -> migrate -> resume, interrupts are migrated and triggered on target after resume), so my doubt was wrong. > >> >>> + */ >>> + >>> + if (migration_is_running()) { >>> + error_setg(errp, "Config synchronization is not allowed " >>> + "during migration"); >>> + return; >>> + } >>> + >>> + if (!runstate_is_running()) { >>> + error_setg(errp, "Config synchronization allowed only in '%s' state, " >> >> Suggest a line break after errp, >> >>> + "current state is '%s'", RunState_str(RUN_STATE_RUNNING), >>> + RunState_str(runstate_get())); >>> + return; >>> + } >>> + >>> + dev = find_device_state(id, true, errp); >>> + if (!dev) { >>> + return; >>> + } >>> + >>> + qdev_sync_config(dev, errp); >>> +} >>> + >>> void hmp_device_add(Monitor *mon, const QDict *qdict) >>> { >>> Error *err = NULL; >> >
Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> writes: > On 30.04.24 11:31, Vladimir Sementsov-Ogievskiy wrote: >> On 30.04.24 11:19, Markus Armbruster wrote: >>> Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> writes: >>> >>>> Add command to sync config from vhost-user backend to the device. It >>>> may be helpful when VHOST_USER_SLAVE_CONFIG_CHANGE_MSG failed or not >>>> triggered interrupt to the guest or just not available (not supported >>>> by vhost-user server). >>>> >>>> Command result is racy if allow it during migration. Let's allow the >>>> sync only in RUNNING state. >>>> >>>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> [...] >>>> diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c >>>> index 264978aa40..47bfc0506e 100644 >>>> --- a/system/qdev-monitor.c >>>> +++ b/system/qdev-monitor.c >>>> @@ -23,6 +23,7 @@ >>>> #include "monitor/monitor.h" >>>> #include "monitor/qdev.h" >>>> #include "sysemu/arch_init.h" >>>> +#include "sysemu/runstate.h" >>>> #include "qapi/error.h" >>>> #include "qapi/qapi-commands-qdev.h" >>>> #include "qapi/qmp/dispatch.h" >>>> @@ -971,6 +972,53 @@ void qmp_device_del(const char *id, Error **errp) >>>> } >>>> } >>>> >>>> +int qdev_sync_config(DeviceState *dev, Error **errp) >>>> +{ >>>> + DeviceClass *dc = DEVICE_GET_CLASS(dev); >>>> + >>>> + if (!dc->sync_config) { >>>> + error_setg(errp, "device-sync-config is not supported for '%s'", >>>> + object_get_typename(OBJECT(dev))); >>>> + return -ENOTSUP; >>>> + } >>>> + >>>> + return dc->sync_config(dev, errp); >>>> +} >>>> + >>>> +void qmp_device_sync_config(const char *id, Error **errp) >>>> +{ >>>> + DeviceState *dev; >>>> + >>>> + /* >>>> + * During migration there is a race between syncing`configuration and >>>> + * migrating it (if migrate first, that target would get outdated version), >>>> + * so let's just not allow it. >>> >>> Wrap comment lines around column 70 for legibility, please. >>> >>>> + * >>>> + * Moreover, let's not rely on setting up interrupts in paused >>>> + * state, which may be a part of migration process. >>> >>> We discussed this in review of v3. You wanted to check whether the >>> problem is real. Is it? >> >> We discussed it later than I've sent v4 :) No, I didn't check yet. > > Checked. Seems this works (in scheme pause -> migrate -> resume, interrupts are migrated and triggered on target after resume), so my doubt was wrong. Thanks! [...]
diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c index 091d2c6acf..2f301f380c 100644 --- a/hw/block/vhost-user-blk.c +++ b/hw/block/vhost-user-blk.c @@ -588,6 +588,7 @@ static void vhost_user_blk_class_init(ObjectClass *klass, void *data) device_class_set_props(dc, vhost_user_blk_properties); dc->vmsd = &vmstate_vhost_user_blk; + dc->sync_config = vhost_user_blk_sync_config; set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); vdc->realize = vhost_user_blk_device_realize; vdc->unrealize = vhost_user_blk_device_unrealize; diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index b1d02f4b3d..0d91e8b5dc 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -2351,6 +2351,14 @@ static void virtio_pci_dc_realize(DeviceState *qdev, Error **errp) vpciklass->parent_dc_realize(qdev, errp); } +static int virtio_pci_sync_config(DeviceState *dev, Error **errp) +{ + VirtIOPCIProxy *proxy = VIRTIO_PCI(dev); + VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); + + return qdev_sync_config(DEVICE(vdev), errp); +} + static void virtio_pci_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); @@ -2367,6 +2375,7 @@ static void virtio_pci_class_init(ObjectClass *klass, void *data) device_class_set_parent_realize(dc, virtio_pci_dc_realize, &vpciklass->parent_dc_realize); rc->phases.hold = virtio_pci_bus_reset_hold; + dc->sync_config = virtio_pci_sync_config; } static const TypeInfo virtio_pci_info = { diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h index 9228e96c87..87135bdcdf 100644 --- a/include/hw/qdev-core.h +++ b/include/hw/qdev-core.h @@ -95,6 +95,7 @@ typedef void (*DeviceUnrealize)(DeviceState *dev); typedef void (*DeviceReset)(DeviceState *dev); typedef void (*BusRealize)(BusState *bus, Error **errp); typedef void (*BusUnrealize)(BusState *bus); +typedef int (*DeviceSyncConfig)(DeviceState *dev, Error **errp); /** * struct DeviceClass - The base class for all devices. @@ -162,6 +163,7 @@ struct DeviceClass { DeviceReset reset; DeviceRealize realize; DeviceUnrealize unrealize; + DeviceSyncConfig sync_config; /** * @vmsd: device state serialisation description for @@ -546,6 +548,7 @@ bool qdev_hotplug_allowed(DeviceState *dev, Error **errp); */ HotplugHandler *qdev_get_hotplug_handler(DeviceState *dev); void qdev_unplug(DeviceState *dev, Error **errp); +int qdev_sync_config(DeviceState *dev, Error **errp); void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev, DeviceState *dev, Error **errp); void qdev_machine_creation_done(void); diff --git a/qapi/qdev.json b/qapi/qdev.json index facaa0bc6a..fc5e125a45 100644 --- a/qapi/qdev.json +++ b/qapi/qdev.json @@ -161,3 +161,26 @@ ## { 'event': 'DEVICE_UNPLUG_GUEST_ERROR', 'data': { '*device': 'str', 'path': 'str' } } + +## +# @device-sync-config: +# +# Synchronize device configuration from host to guest part. First, +# copy the configuration from the host part (backend) to the guest +# part (frontend). Then notify guest software that device +# configuration changed. +# The command may be used to notify the guest about block device +# capcity change. Currently only vhost-user-blk device supports +# this. +# +# @id: the device's ID or QOM path +# +# Features: +# +# @unstable: The command is experimental. +# +# Since: 9.1 +## +{ 'command': 'device-sync-config', + 'features': [ 'unstable' ], + 'data': {'id': 'str'} } diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c index 264978aa40..47bfc0506e 100644 --- a/system/qdev-monitor.c +++ b/system/qdev-monitor.c @@ -23,6 +23,7 @@ #include "monitor/monitor.h" #include "monitor/qdev.h" #include "sysemu/arch_init.h" +#include "sysemu/runstate.h" #include "qapi/error.h" #include "qapi/qapi-commands-qdev.h" #include "qapi/qmp/dispatch.h" @@ -971,6 +972,53 @@ void qmp_device_del(const char *id, Error **errp) } } +int qdev_sync_config(DeviceState *dev, Error **errp) +{ + DeviceClass *dc = DEVICE_GET_CLASS(dev); + + if (!dc->sync_config) { + error_setg(errp, "device-sync-config is not supported for '%s'", + object_get_typename(OBJECT(dev))); + return -ENOTSUP; + } + + return dc->sync_config(dev, errp); +} + +void qmp_device_sync_config(const char *id, Error **errp) +{ + DeviceState *dev; + + /* + * During migration there is a race between syncing`configuration and + * migrating it (if migrate first, that target would get outdated version), + * so let's just not allow it. + * + * Moreover, let's not rely on setting up interrupts in paused + * state, which may be a part of migration process. + */ + + if (migration_is_running()) { + error_setg(errp, "Config synchronization is not allowed " + "during migration"); + return; + } + + if (!runstate_is_running()) { + error_setg(errp, "Config synchronization allowed only in '%s' state, " + "current state is '%s'", RunState_str(RUN_STATE_RUNNING), + RunState_str(runstate_get())); + return; + } + + dev = find_device_state(id, true, errp); + if (!dev) { + return; + } + + qdev_sync_config(dev, errp); +} + void hmp_device_add(Monitor *mon, const QDict *qdict) { Error *err = NULL;
Add command to sync config from vhost-user backend to the device. It may be helpful when VHOST_USER_SLAVE_CONFIG_CHANGE_MSG failed or not triggered interrupt to the guest or just not available (not supported by vhost-user server). Command result is racy if allow it during migration. Let's allow the sync only in RUNNING state. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> --- hw/block/vhost-user-blk.c | 1 + hw/virtio/virtio-pci.c | 9 ++++++++ include/hw/qdev-core.h | 3 +++ qapi/qdev.json | 23 +++++++++++++++++++ system/qdev-monitor.c | 48 +++++++++++++++++++++++++++++++++++++++ 5 files changed, 84 insertions(+)