qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Peter Krempa <pkrempa@redhat.com>
To: qemu-devel@nongnu.org
Cc: Kevin Wolf <kwolf@redhat.com>,
	Markus Armbruster <armbru@redhat.com>,
	Michael Roth <mdroth@linux.vnet.ibm.com>
Subject: [PATCH v2 1/2] qapi: Add feature flags to commands in qapi introspection
Date: Fri, 20 Sep 2019 16:26:44 +0200	[thread overview]
Message-ID: <96cc954e1cba111a4565123badb42c36e534a5d3.1568989362.git.pkrempa@redhat.com> (raw)
In-Reply-To: <cover.1568989362.git.pkrempa@redhat.com>

Similarly to features for struct types introduce the feature flags also
for commands. This will allow notifying management layers of fixes and
compatible changes in the behaviour of a command which may not be
detectable any other way.

The changes were heavily inspired by commit 6a8c0b51025.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
---
 docs/devel/qapi-code-gen.txt   |  4 ++--
 qapi/introspect.json           |  6 ++++-
 scripts/qapi/commands.py       |  3 ++-
 scripts/qapi/common.py         | 40 +++++++++++++++++++++++++++++-----
 scripts/qapi/doc.py            |  3 ++-
 scripts/qapi/introspect.py     |  7 +++++-
 tests/qapi-schema/test-qapi.py |  7 +++++-
 7 files changed, 58 insertions(+), 12 deletions(-)

diff --git a/docs/devel/qapi-code-gen.txt b/docs/devel/qapi-code-gen.txt
index e8ec8ac1de..d465cc6330 100644
--- a/docs/devel/qapi-code-gen.txt
+++ b/docs/devel/qapi-code-gen.txt
@@ -726,8 +726,8 @@ change in the QMP syntax (usually by allowing values or operations that
 previously resulted in an error). QMP clients may still need to know
 whether the extension is available.

-For this purpose, a list of features can be specified for a struct type.
-This is exposed to the client as a list of string, where each string
+For this purpose, a list of features can be specified for a command or struct
+type. This is exposed to the client as a list of strings, where each string
 signals that this build of QEMU shows a certain behaviour.

 In the schema, features can be specified as simple strings, for example:
diff --git a/qapi/introspect.json b/qapi/introspect.json
index 1843c1cb17..031a954fa9 100644
--- a/qapi/introspect.json
+++ b/qapi/introspect.json
@@ -266,13 +266,17 @@
 # @allow-oob: whether the command allows out-of-band execution,
 #             defaults to false (Since: 2.12)
 #
+# @features: names of features associated with the command, in no particular
+#            order. (since 4.2)
+#
 # TODO: @success-response (currently irrelevant, because it's QGA, not QMP)
 #
 # Since: 2.5
 ##
 { 'struct': 'SchemaInfoCommand',
   'data': { 'arg-type': 'str', 'ret-type': 'str',
-            '*allow-oob': 'bool' } }
+            '*allow-oob': 'bool',
+            '*features': [ 'str' ] } }

 ##
 # @SchemaInfoEvent:
diff --git a/scripts/qapi/commands.py b/scripts/qapi/commands.py
index b929e07be4..6cfe6cdd9e 100644
--- a/scripts/qapi/commands.py
+++ b/scripts/qapi/commands.py
@@ -276,7 +276,8 @@ void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds);
         genc.add(gen_registry(self._regy.get_content(), self._prefix))

     def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
-                      success_response, boxed, allow_oob, allow_preconfig):
+                      success_response, boxed, allow_oob, allow_preconfig,
+                      features):
         if not gen:
             return
         # FIXME: If T is a user-defined type, the user is responsible
diff --git a/scripts/qapi/common.py b/scripts/qapi/common.py
index d61bfdc526..1502820f46 100644
--- a/scripts/qapi/common.py
+++ b/scripts/qapi/common.py
@@ -838,6 +838,7 @@ def check_type(info, source, value, allow_array=False,
 def check_command(expr, info):
     name = expr['command']
     boxed = expr.get('boxed', False)
+    features = expr.get('features')

     args_meta = ['struct']
     if boxed:
@@ -852,6 +853,19 @@ def check_command(expr, info):
                expr.get('returns'), allow_array=True,
                allow_optional=True, allow_metas=returns_meta)

+    if features:
+        if not isinstance(features, list):
+            raise QAPISemError(info,
+                               "Command '%s' requires an array for 'features'" %
+                               name)
+        for f in features:
+            assert isinstance(f, dict)
+            check_known_keys(info, "feature of command %s" % name, f,
+                             ['name'], ['if'])
+
+            check_if(f, info)
+            check_name(info, "Feature of command %s" % name, f['name'])
+

 def check_event(expr, info):
     name = expr['event']
@@ -1138,8 +1152,10 @@ def check_exprs(exprs):
             meta = 'command'
             check_keys(expr_elem, 'command', [],
                        ['data', 'returns', 'gen', 'success-response',
-                        'boxed', 'allow-oob', 'allow-preconfig', 'if'])
+                        'boxed', 'allow-oob', 'allow-preconfig', 'if',
+                        'features'])
             normalize_members(expr.get('data'))
+            normalize_features(expr.get('features'))
         elif 'event' in expr:
             meta = 'event'
             check_keys(expr_elem, 'event', [], ['data', 'boxed', 'if'])
@@ -1283,7 +1299,8 @@ class QAPISchemaVisitor(object):
         pass

     def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
-                      success_response, boxed, allow_oob, allow_preconfig):
+                      success_response, boxed, allow_oob, allow_preconfig,
+                      features):
         pass

     def visit_event(self, name, info, ifcond, arg_type, boxed):
@@ -1697,10 +1714,14 @@ class QAPISchemaAlternateType(QAPISchemaType):

 class QAPISchemaCommand(QAPISchemaEntity):
     def __init__(self, name, info, doc, ifcond, arg_type, ret_type,
-                 gen, success_response, boxed, allow_oob, allow_preconfig):
+                 gen, success_response, boxed, allow_oob, allow_preconfig,
+                 features):
         QAPISchemaEntity.__init__(self, name, info, doc, ifcond)
         assert not arg_type or isinstance(arg_type, str)
         assert not ret_type or isinstance(ret_type, str)
+        for f in features:
+            assert isinstance(f, QAPISchemaFeature)
+            f.set_owner(name)
         self._arg_type_name = arg_type
         self.arg_type = None
         self._ret_type_name = ret_type
@@ -1710,6 +1731,7 @@ class QAPISchemaCommand(QAPISchemaEntity):
         self.boxed = boxed
         self.allow_oob = allow_oob
         self.allow_preconfig = allow_preconfig
+        self.features = features

     def check(self, schema):
         QAPISchemaEntity.check(self, schema)
@@ -1731,12 +1753,18 @@ class QAPISchemaCommand(QAPISchemaEntity):
             self.ret_type = schema.lookup_type(self._ret_type_name)
             assert isinstance(self.ret_type, QAPISchemaType)

+        # Features are in a name space separate from members
+        seen = {}
+        for f in self.features:
+            f.check_clash(self.info, seen)
+
     def visit(self, visitor):
         visitor.visit_command(self.name, self.info, self.ifcond,
                               self.arg_type, self.ret_type,
                               self.gen, self.success_response,
                               self.boxed, self.allow_oob,
-                              self.allow_preconfig)
+                              self.allow_preconfig,
+                              self.features)


 class QAPISchemaEvent(QAPISchemaEntity):
@@ -1989,6 +2017,7 @@ class QAPISchema(object):
         allow_oob = expr.get('allow-oob', False)
         allow_preconfig = expr.get('allow-preconfig', False)
         ifcond = expr.get('if')
+        features = expr.get('features', [])
         if isinstance(data, OrderedDict):
             data = self._make_implicit_object_type(
                 name, info, doc, ifcond, 'arg', self._make_members(data, info))
@@ -1997,7 +2026,8 @@ class QAPISchema(object):
             rets = self._make_array_type(rets[0], info)
         self._def_entity(QAPISchemaCommand(name, info, doc, ifcond, data, rets,
                                            gen, success_response,
-                                           boxed, allow_oob, allow_preconfig))
+                                           boxed, allow_oob, allow_preconfig,
+                                           self._make_features(features)))

     def _def_event(self, expr, info, doc):
         name = expr['event']
diff --git a/scripts/qapi/doc.py b/scripts/qapi/doc.py
index 5fc0fc7e06..aa4c557244 100755
--- a/scripts/qapi/doc.py
+++ b/scripts/qapi/doc.py
@@ -249,7 +249,8 @@ class QAPISchemaGenDocVisitor(qapi.common.QAPISchemaVisitor):
                                body=texi_entity(doc, 'Members', ifcond)))

     def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
-                      success_response, boxed, allow_oob, allow_preconfig):
+                      success_response, boxed, allow_oob, allow_preconfig,
+                      features):
         doc = self.cur_doc
         if boxed:
             body = texi_body(doc)
diff --git a/scripts/qapi/introspect.py b/scripts/qapi/introspect.py
index f62cf0a2e1..36a5b195e5 100644
--- a/scripts/qapi/introspect.py
+++ b/scripts/qapi/introspect.py
@@ -206,13 +206,18 @@ const QLitObject %(c_name)s = %(c_string)s;
                            for m in variants.variants]}, ifcond)

     def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
-                      success_response, boxed, allow_oob, allow_preconfig):
+                      success_response, boxed, allow_oob, allow_preconfig,
+                      features):
         arg_type = arg_type or self._schema.the_empty_object_type
         ret_type = ret_type or self._schema.the_empty_object_type
         obj = {'arg-type': self._use_type(arg_type),
                'ret-type': self._use_type(ret_type)}
         if allow_oob:
             obj['allow-oob'] = allow_oob
+
+        if features:
+            obj['features'] = [(f.name, {'if': f.ifcond}) for f in features]
+
         self._gen_qlit(name, 'command', obj, ifcond)

     def visit_event(self, name, info, ifcond, arg_type, boxed):
diff --git a/tests/qapi-schema/test-qapi.py b/tests/qapi-schema/test-qapi.py
index b0f770b9bd..def34aa489 100644
--- a/tests/qapi-schema/test-qapi.py
+++ b/tests/qapi-schema/test-qapi.py
@@ -60,13 +60,18 @@ class QAPISchemaTestVisitor(QAPISchemaVisitor):
         self._print_if(ifcond)

     def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
-                      success_response, boxed, allow_oob, allow_preconfig):
+                      success_response, boxed, allow_oob, allow_preconfig,
+                      features):
         print('command %s %s -> %s'
               % (name, arg_type and arg_type.name,
                  ret_type and ret_type.name))
         print('   gen=%s success_response=%s boxed=%s oob=%s preconfig=%s'
               % (gen, success_response, boxed, allow_oob, allow_preconfig))
         self._print_if(ifcond)
+        if features:
+            for f in features:
+                print('    feature %s' % f.name)
+                self._print_if(f.ifcond, 8)

     def visit_event(self, name, info, ifcond, arg_type, boxed):
         print('event %s %s' % (name, arg_type and arg_type.name))
-- 
2.21.0



  reply	other threads:[~2019-09-20 14:48 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-20 14:26 [PATCH v2 0/2] qapi: Add detection for the 'savevm' fix for blockdev Peter Krempa
2019-09-20 14:26 ` Peter Krempa [this message]
2019-10-01  6:40   ` [PATCH v2 1/2] qapi: Add feature flags to commands in qapi introspection Markus Armbruster
2019-10-01 14:17     ` Peter Krempa
2019-10-01 20:01   ` Markus Armbruster
2019-10-02  6:15     ` Markus Armbruster
2019-09-20 14:26 ` [PATCH v2 2/2] qapi: Allow introspecting fix for savevm's cooperation with blockdev Peter Krempa
2019-10-01 19:34   ` Markus Armbruster
2019-10-01 21:07     ` Eric Blake
2019-10-02 11:57       ` Markus Armbruster
2019-10-10 15:07         ` Kevin Wolf
2019-10-11  6:08           ` Markus Armbruster
2019-10-11  9:00             ` Kevin Wolf
2019-10-11 11:10               ` Markus Armbruster
2019-09-30 13:04 ` [PATCH v2 0/2] qapi: Add detection for the 'savevm' fix for blockdev Peter Krempa

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=96cc954e1cba111a4565123badb42c36e534a5d3.1568989362.git.pkrempa@redhat.com \
    --to=pkrempa@redhat.com \
    --cc=armbru@redhat.com \
    --cc=kwolf@redhat.com \
    --cc=mdroth@linux.vnet.ibm.com \
    --cc=qemu-devel@nongnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).