+##
+# @BlockDriverStats:
+#
+# Statistics of a block driver (driver-specific)
+#
+# Since: 2.12
+##
+{ 'union': 'BlockDriverStats',
+ 'data': {
+ 'file': 'BlockDriverStatsFile'
+ } }
Markus has been adamant that we add no new "simple unions" (unions with
a 'discriminator' field) - because they are anything but simple in the
long run.
Indeed. You could make this a flat union, similar to BlockdevOptions:
{ 'union': 'BlockDriverStats':
'base': { 'driver': 'BlockdevDriver' },
'discriminator': 'driver',
'data': {
'file': 'BlockDriverStatsFile',
... } }
However:
+
+##
# @BlockStats:
#
# Statistics of a virtual block device or a block backing device.
@@ -785,6 +819,8 @@
#
# @stats: A @BlockDeviceStats for the device.
#
+# @driver-stats: Optional driver-specific statistics. (Since 2.12)
+#
# @parent: This describes the file block device if it has one.
# Contains recursively the statistics of the underlying
# protocol (e.g. the host file for a qcow2 image). If there is
@@ -798,6 +834,7 @@
{ 'struct': 'BlockStats',
'data': {'*device': 'str', '*node-name': 'str',
'stats': 'BlockDeviceStats',
+ '*driver-stats': 'BlockDriverStats',
You're adding a union of driver-specific stats to a struct of generic
stats. That's unnecessarily complicated. Instead, turn the struct of
generic stats into a flat union, like this:
{ 'union': 'BlockStats',
'base': { ... the generic stats, i.e. the members of BlockStats
before this patch ...
'driver': 'BlockdevDriver' }
'discriminator': 'driver',
'data': {
'file': 'BlockDriverStatsFile',
... } }