[PATCH v3 07/30] qapi/qom: Add ObjectOptions for rng-*, deprecate 'opened'

[Kevin Wolf]

This adds a QAPI schema for the properties of the rng-* objects.

The 'opened' property doesn't seem to make sense as an external
interface: It is automatically set to true in ucc->complete, and
explicitly setting it to true earlier just means that trying to set
additional options will result in an error. After the property has once
been set to true (i.e. when the object construction has completed), it
can never be reset to false. In other words, the 'opened' property is
useless. Mark it as deprecated in the schema from the start.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 qapi/qom.json              | 56 ++++++++++++++++++++++++++++++++++++--
 docs/system/deprecated.rst |  9 ++++++
 2 files changed, 63 insertions(+), 2 deletions(-)

diff --git a/qapi/qom.json b/qapi/qom.json
index 8c0e06c198..6d3b8c4fe0 100644
--- a/qapi/qom.json
+++ b/qapi/qom.json
@@ -382,6 +382,52 @@
             '*hugetlbsize': 'size',
             '*seal': 'bool' } }
 
+##
+# @RngProperties:
+#
+# Properties for objects of classes derived from rng.
+#
+# @opened: if true, the device is opened immediately when applying this option
+#          and will probably fail when processing the next option. Don't use;
+#          only provided for compatibility. (default: false)
+#
+# Features:
+# @deprecated: Member @opened is deprecated.  Setting true doesn't make sense,
+#              and false is already the default.
+#
+# Since: 1.3
+##
+{ 'struct': 'RngProperties',
+  'data': { '*opened': { 'type': 'bool', 'features': ['deprecated'] } } }
+
+##
+# @RngEgdProperties:
+#
+# Properties for rng-egd objects.
+#
+# @chardev: the name of a character device backend that provides the connection
+#           to the RNG daemon
+#
+# Since: 1.3
+##
+{ 'struct': 'RngEgdProperties',
+  'base': 'RngProperties',
+  'data': { 'chardev': 'str' } }
+
+##
+# @RngRandomProperties:
+#
+# Properties for rng-random objects.
+#
+# @filename: the filename of the device on the host to obtain entropy from
+#            (default: "/dev/urandom")
+#
+# Since: 1.3
+##
+{ 'struct': 'RngRandomProperties',
+  'base': 'RngProperties',
+  'data': { '*filename': 'str' } }
+
 ##
 # @ObjectType:
 #
@@ -400,7 +446,10 @@
     'iothread',
     'memory-backend-file',
     'memory-backend-memfd',
-    'memory-backend-ram'
+    'memory-backend-ram',
+    'rng-builtin',
+    'rng-egd',
+    'rng-random'
   ] }
 
 ##
@@ -432,7 +481,10 @@
       'memory-backend-file':        'MemoryBackendFileProperties',
       'memory-backend-memfd':       { 'type': 'MemoryBackendMemfdProperties',
                                       'if': 'defined(CONFIG_LINUX)' },
-      'memory-backend-ram':         'MemoryBackendProperties'
+      'memory-backend-ram':         'MemoryBackendProperties',
+      'rng-builtin':                'RngProperties',
+      'rng-egd':                    'RngEgdProperties',
+      'rng-random':                 'RngRandomProperties'
   } }
 
 ##
diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst
index 893f3e8579..3dac79f600 100644
--- a/docs/system/deprecated.rst
+++ b/docs/system/deprecated.rst
@@ -153,6 +153,15 @@ The ``-writeconfig`` option is not able to serialize the 
entire contents
 of the QEMU command line.  It is thus considered a failed experiment
 and deprecated, with no current replacement.
 
+``opened`` property of ``rng-*`` objects (since 6.0.0)
+''''''''''''''''''''''''''''''''''''''''''''''''''''''
+
+The only effect of specifying ``opened=on`` in the command line or QMP
+``object-add`` is that the device is opened immediately, possibly before all
+other options have been processed.  This will either have no effect (if
+``opened`` was the last option) or cause errors.  The property is therefore
+useless and should not be specified.
+
 QEMU Machine Protocol (QMP) commands
 ------------------------------------
 
-- 
2.29.2