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).
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
---
hw/block/vhost-user-blk.c | 27 ++++++++++++++++++++-------
hw/virtio/virtio-pci.c | 9 +++++++++
include/hw/qdev-core.h | 3 +++
qapi/qdev.json | 17 +++++++++++++++++
system/qdev-monitor.c | 23 +++++++++++++++++++++++
5 files changed, 72 insertions(+), 7 deletions(-)
diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
index 9e6bbc6950..2f301f380c 100644
--- a/hw/block/vhost-user-blk.c
+++ b/hw/block/vhost-user-blk.c
@@ -88,27 +88,39 @@ static void vhost_user_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
s->blkcfg.wce = blkcfg->wce;
}
+static int vhost_user_blk_sync_config(DeviceState *dev, Error **errp)
+{
+ int ret;
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserBlk *s = VHOST_USER_BLK(vdev);
+
+ ret = vhost_dev_get_config(&s->dev, (uint8_t *)&s->blkcfg,
+ vdev->config_len, errp);
+ if (ret < 0) {
+ return ret;
+ }
+
+ memcpy(vdev->config, &s->blkcfg, vdev->config_len);
+ virtio_notify_config(vdev);
+
+ return 0;
+}
+
static int vhost_user_blk_handle_config_change(struct vhost_dev *dev)
{
int ret;
- VirtIODevice *vdev = dev->vdev;
- VHostUserBlk *s = VHOST_USER_BLK(dev->vdev);
Error *local_err = NULL;
if (!dev->started) {
return 0;
}
- ret = vhost_dev_get_config(dev, (uint8_t *)&s->blkcfg,
- vdev->config_len, &local_err);
+ ret = vhost_user_blk_sync_config(DEVICE(dev->vdev), &local_err);
if (ret < 0) {
error_report_err(local_err);
return ret;
}
- memcpy(dev->vdev->config, &s->blkcfg, vdev->config_len);
- virtio_notify_config(dev->vdev);
-
return 0;
}
@@ -576,6 +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 1a7039fb0c..1197341a3c 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -2318,6 +2318,14 @@ 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);
@@ -2334,6 +2342,7 @@ 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 32ffaee644..6ece164172 100644
--- a/qapi/qdev.json
+++ b/qapi/qdev.json
@@ -162,3 +162,20 @@
##
{ 'event': 'DEVICE_UNPLUG_GUEST_ERROR',
'data': { '*device': 'str', 'path': 'str' } }
+
+##
+# @device-sync-config:
+#
+# Synchronize config from backend to the guest.
+#
+# @id: the device's ID or QOM path
+#
+# Features:
+#
+# @unstable: The command is experimental.
+#
+# Since: 9.0
+##
+{ 'command': 'device-sync-config',
+ 'features': [ 'unstable' ],
+ 'data': {'id': 'str'} }
diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c
index cf7481e416..e3107a12d7 100644
--- a/system/qdev-monitor.c
+++ b/system/qdev-monitor.c
@@ -968,6 +968,29 @@ 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 = 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;
--
2.34.1Vladimir 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).
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
> ---
> hw/block/vhost-user-blk.c | 27 ++++++++++++++++++++-------
> hw/virtio/virtio-pci.c | 9 +++++++++
> include/hw/qdev-core.h | 3 +++
> qapi/qdev.json | 17 +++++++++++++++++
> system/qdev-monitor.c | 23 +++++++++++++++++++++++
> 5 files changed, 72 insertions(+), 7 deletions(-)
>
> diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
> index 9e6bbc6950..2f301f380c 100644
> --- a/hw/block/vhost-user-blk.c
> +++ b/hw/block/vhost-user-blk.c
> @@ -88,27 +88,39 @@ static void vhost_user_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
> s->blkcfg.wce = blkcfg->wce;
> }
>
> +static int vhost_user_blk_sync_config(DeviceState *dev, Error **errp)
> +{
> + int ret;
> + VirtIODevice *vdev = VIRTIO_DEVICE(dev);
> + VHostUserBlk *s = VHOST_USER_BLK(vdev);
> +
> + ret = vhost_dev_get_config(&s->dev, (uint8_t *)&s->blkcfg,
> + vdev->config_len, errp);
> + if (ret < 0) {
> + return ret;
> + }
> +
> + memcpy(vdev->config, &s->blkcfg, vdev->config_len);
> + virtio_notify_config(vdev);
> +
> + return 0;
> +}
> +
> static int vhost_user_blk_handle_config_change(struct vhost_dev *dev)
> {
> int ret;
> - VirtIODevice *vdev = dev->vdev;
> - VHostUserBlk *s = VHOST_USER_BLK(dev->vdev);
> Error *local_err = NULL;
>
> if (!dev->started) {
> return 0;
> }
>
> - ret = vhost_dev_get_config(dev, (uint8_t *)&s->blkcfg,
> - vdev->config_len, &local_err);
> + ret = vhost_user_blk_sync_config(DEVICE(dev->vdev), &local_err);
> if (ret < 0) {
> error_report_err(local_err);
> return ret;
> }
>
> - memcpy(dev->vdev->config, &s->blkcfg, vdev->config_len);
> - virtio_notify_config(dev->vdev);
> -
> return 0;
> }
>
> @@ -576,6 +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 1a7039fb0c..1197341a3c 100644
> --- a/hw/virtio/virtio-pci.c
> +++ b/hw/virtio/virtio-pci.c
> @@ -2318,6 +2318,14 @@ 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);
> @@ -2334,6 +2342,7 @@ 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 32ffaee644..6ece164172 100644
> --- a/qapi/qdev.json
> +++ b/qapi/qdev.json
> @@ -162,3 +162,20 @@
> ##
> { 'event': 'DEVICE_UNPLUG_GUEST_ERROR',
> 'data': { '*device': 'str', 'path': 'str' } }
> +
> +##
> +# @device-sync-config:
> +#
> +# Synchronize config from backend to the guest.
> +#
> +# @id: the device's ID or QOM path
> +#
> +# Features:
> +#
> +# @unstable: The command is experimental.
> +#
> +# Since: 9.0
> +##
Even for an experimental command a bit more guidance on intended would
be good.
The commit message describes this as a "command to sync config from
vhost-user backend to the device". Here, there's no mention of
vhost-user.
Could the command make sense for devices other than vhost-user?
> +{ 'command': 'device-sync-config',
> + 'features': [ 'unstable' ],
> + 'data': {'id': 'str'} }
> diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c
> index cf7481e416..e3107a12d7 100644
> --- a/system/qdev-monitor.c
> +++ b/system/qdev-monitor.c
> @@ -968,6 +968,29 @@ 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 = 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 07.03.24 12:54, 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).
>>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
>> ---
>> hw/block/vhost-user-blk.c | 27 ++++++++++++++++++++-------
>> hw/virtio/virtio-pci.c | 9 +++++++++
>> include/hw/qdev-core.h | 3 +++
>> qapi/qdev.json | 17 +++++++++++++++++
>> system/qdev-monitor.c | 23 +++++++++++++++++++++++
>> 5 files changed, 72 insertions(+), 7 deletions(-)
>>
>> diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
>> index 9e6bbc6950..2f301f380c 100644
>> --- a/hw/block/vhost-user-blk.c
>> +++ b/hw/block/vhost-user-blk.c
>> @@ -88,27 +88,39 @@ static void vhost_user_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
>> s->blkcfg.wce = blkcfg->wce;
>> }
>>
>> +static int vhost_user_blk_sync_config(DeviceState *dev, Error **errp)
>> +{
>> + int ret;
>> + VirtIODevice *vdev = VIRTIO_DEVICE(dev);
>> + VHostUserBlk *s = VHOST_USER_BLK(vdev);
>> +
>> + ret = vhost_dev_get_config(&s->dev, (uint8_t *)&s->blkcfg,
>> + vdev->config_len, errp);
>> + if (ret < 0) {
>> + return ret;
>> + }
>> +
>> + memcpy(vdev->config, &s->blkcfg, vdev->config_len);
>> + virtio_notify_config(vdev);
>> +
>> + return 0;
>> +}
>> +
>> static int vhost_user_blk_handle_config_change(struct vhost_dev *dev)
>> {
>> int ret;
>> - VirtIODevice *vdev = dev->vdev;
>> - VHostUserBlk *s = VHOST_USER_BLK(dev->vdev);
>> Error *local_err = NULL;
>>
>> if (!dev->started) {
>> return 0;
>> }
>>
>> - ret = vhost_dev_get_config(dev, (uint8_t *)&s->blkcfg,
>> - vdev->config_len, &local_err);
>> + ret = vhost_user_blk_sync_config(DEVICE(dev->vdev), &local_err);
>> if (ret < 0) {
>> error_report_err(local_err);
>> return ret;
>> }
>>
>> - memcpy(dev->vdev->config, &s->blkcfg, vdev->config_len);
>> - virtio_notify_config(dev->vdev);
>> -
>> return 0;
>> }
>>
>> @@ -576,6 +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 1a7039fb0c..1197341a3c 100644
>> --- a/hw/virtio/virtio-pci.c
>> +++ b/hw/virtio/virtio-pci.c
>> @@ -2318,6 +2318,14 @@ 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);
>> @@ -2334,6 +2342,7 @@ 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 32ffaee644..6ece164172 100644
>> --- a/qapi/qdev.json
>> +++ b/qapi/qdev.json
>> @@ -162,3 +162,20 @@
>> ##
>> { 'event': 'DEVICE_UNPLUG_GUEST_ERROR',
>> 'data': { '*device': 'str', 'path': 'str' } }
>> +
>> +##
>> +# @device-sync-config:
>> +#
>> +# Synchronize config from backend to the guest.
>> +#
>> +# @id: the device's ID or QOM path
>> +#
>> +# Features:
>> +#
>> +# @unstable: The command is experimental.
>> +#
>> +# Since: 9.0
>> +##
>
> Even for an experimental command a bit more guidance on intended would
> be good.
Will add
>
> The commit message describes this as a "command to sync config from
> vhost-user backend to the device". Here, there's no mention of
> vhost-user.
>
> Could the command make sense for devices other than vhost-user?
Yes it should work for any kind of backend, which can't notify Qemu about changed configuration (like disk size).
>
>> +{ 'command': 'device-sync-config',
>> + 'features': [ 'unstable' ],
>> + 'data': {'id': 'str'} }
>> diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c
>> index cf7481e416..e3107a12d7 100644
>> --- a/system/qdev-monitor.c
>> +++ b/system/qdev-monitor.c
>> @@ -968,6 +968,29 @@ 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 = 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;
>
--
Best regards,
Vladimir
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