@@ -2825,13 +2825,14 @@
# @blklogwrites: Since 3.0
# @blkreplay: Since 4.2
# @compress: Since 5.0
+# @copy-before-write: Since 6.2
#
# Since: 2.9
##
{ 'enum': 'BlockdevDriver',
'data': [ 'blkdebug', 'blklogwrites', 'blkreplay', 'blkverify', 'bochs',
- 'cloop', 'compress', 'copy-on-read', 'dmg', 'file', 'ftp', 'ftps',
- 'gluster',
+ 'cloop', 'compress', 'copy-before-write', 'copy-on-read', 'dmg',
+ 'file', 'ftp', 'ftps', 'gluster',
{'name': 'host_cdrom', 'if': 'HAVE_HOST_BLOCK_DEVICE' },
{'name': 'host_device', 'if': 'HAVE_HOST_BLOCK_DEVICE' },
'http', 'https', 'iscsi',
@@ -4049,6 +4050,25 @@
'base': 'BlockdevOptionsGenericFormat',
'data': { '*bottom': 'str' } }
+##
+# @BlockdevOptionsCbw:
+#
+# Driver specific block device options for the copy-before-write driver,
+# which does so called copy-before-write operations: when data is
+# written to the filter, the filter first reads corresponding blocks
+# from its file child and copies them to @target child. After successfully
+# copying, the write request is propagated to file child. If copying
+# fails, the original write request is failed too and no data is written
+# to file child.
+#
+# @target: The target for copy-before-write operations.
+#
+# Since: 6.2
+##
+{ 'struct': 'BlockdevOptionsCbw',
+ 'base': 'BlockdevOptionsGenericFormat',
+ 'data': { 'target': 'BlockdevRef' } }
+
##
# @BlockdevOptions:
#
@@ -4101,6 +4121,7 @@
'bochs': 'BlockdevOptionsGenericFormat',
'cloop': 'BlockdevOptionsGenericFormat',
'compress': 'BlockdevOptionsGenericFormat',
+ 'copy-before-write':'BlockdevOptionsCbw',
'copy-on-read':'BlockdevOptionsCor',
'dmg': 'BlockdevOptionsGenericFormat',
'file': 'BlockdevOptionsFile',