Commit Graph

352 Commits

Author SHA1 Message Date
Paolo Bonzini 3bb6944585 qom: export more functions for use with non-UserCreatable objects
Machines and accelerators are not user-creatable but they are going
to share similar command-line parsing machinery.  Export functions
that will be used with -machine and -accel in softmmu/vl.c.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-07-06 08:33:51 +02:00
Paolo Bonzini bc2f4fcb1d qom: move user_creatable_add_opts logic to vl.c and QAPIfy it
Emulators are currently using OptsVisitor (via user_creatable_add_opts)
to parse the -object command line option.  This has one extra feature,
compared to keyval, which is automatic conversion of integers to lists
as well as support for lists as repeated options:

  -object memory-backend-ram,id=pc.ram,size=1048576000,host-nodes=0,policy=bind

So we cannot replace OptsVisitor with keyval right now.  Still, this
patch moves the user_creatable_add_opts logic to vl.c since it is
not needed anywhere else, and makes it go through user_creatable_add_qapi.

In order to minimize code changes, the predicate still takes a string.
This can be changed later to use the ObjectType QAPI enum directly.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210312173547.1283477-3-pbonzini@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-03-19 10:18:17 +01:00
Kevin Wolf ddf6dae7e3 qom: Add user_creatable_parse_str()
The system emulator has a more complicated way of handling command line
options in that it reorders options before it processes them. This means
that parsing object options and creating the object happen at two
different points. Split the parsing part into a separate function that
can be reused by the system emulator command line.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2021-03-19 10:17:14 +01:00
Kevin Wolf ffd58ef88c qom: Add user_creatable_add_from_str()
This is a version of user_creatable_process_cmdline() with an Error
parameter that never calls exit() and is therefore usable in HMP.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2021-03-19 10:17:14 +01:00
Kevin Wolf f375026606 qom: Factor out user_creatable_process_cmdline()
The implementation for --object can be shared between
qemu-storage-daemon and other binaries, so move it into a function in
qom/object_interfaces.c that is accessible from everywhere.

This also requires moving the implementation of qmp_object_add() into a
new user_creatable_add_qapi(), because qom/qom-qmp-cmds.c is not linked
for tools.

user_creatable_print_help_from_qdict() can become static now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2021-03-19 10:17:14 +01:00
Kevin Wolf c923112390 qom: Remove user_creatable_add_dict()
This function is now unused and can be removed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2021-03-19 10:17:14 +01:00
Kevin Wolf 9151e59a8b qapi/qom: QAPIfy object-add
This converts object-add from 'gen': false to the ObjectOptions QAPI
type. As an immediate benefit, clients can now use QAPI schema
introspection for user creatable QOM objects.

It is also the first step towards making the QAPI schema the only
external interface for the creation of user creatable objects. Once all
other places (HMP and command lines of the system emulator and all
tools) go through QAPI, too, some object implementations can be
simplified because some checks (e.g. that mandatory options are set) are
already performed by QAPI, and in another step, QOM boilerplate code
could be generated from the schema.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2021-03-19 10:17:14 +01:00
Greg Kurz a8dc82ce82 qom: Allow optional sugar props
Global properties have an @optional field, which allows to apply a given
property to a given type even if one of its subclasses doesn't support
it. This is especially used in the compat code when dealing with the
"disable-modern" and "disable-legacy" properties and the "virtio-pci"
type.

Allow object_register_sugar_prop() to set this field as well.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <159738953558.377274.16617742952571083440.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2021-02-08 16:57:37 +11:00
Kevin Wolf c9ac145843 qom: Add user_creatable_print_help_from_qdict()
This adds a function that, given a QDict of non-help options, prints
help for user creatable objects.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201007164903.282198-4-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-10-15 16:06:27 +02:00
Eduardo Habkost ff59780f8d qom: Explicitly tag doc comments for typedefs and structs
If we explicitly indicate we are documenting a typedef or a
struct, we'll be able to remove the $decl_type='type name' hack
from kernel-doc.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201003024123.193840-4-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-10-06 11:09:35 -04:00
Eduardo Habkost b99e80cb0f docs/devel/qom: Remove usage of <code>
<code> is not valid reST syntax.

Function @argument references don't need additional markup, so
just remove <code></code>.

Constants were changed to use reST ``code`` syntax

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201003025424.199291-6-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-10-06 11:09:35 -04:00
Eduardo Habkost d5b9959dd7 qom: Fix DECLARE_*CHECKER documentation
Correct copy/paste mistake in the DECLARE_INSTANCE_CHECKER and
DECLARE_CLASS_CHECKERS documentation.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201003025424.199291-2-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-10-06 11:09:35 -04:00
Paolo Bonzini 9cb54b18e8 docs: Move object.h overview doc comment to qom.rst
Move the whole contents of the overview doc comment from object.h
to qom.rst.

This makes the documentation source easier to read and edit, and
also solves the backslash escaping issue at the typecasting macro
examples.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200910221526.10041-10-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-30 19:11:36 +02:00
Eduardo Habkost 6cf164c00f qom: Add code block markup to all code blocks
Convert all example/codelisting markup to Sphinx code-block.

There are a few sections where backslashes at the end of lines
break code formatting.  A comment was added noting that this is
an issue.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200910221526.10041-8-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-30 19:11:36 +02:00
Eduardo Habkost 9bbfd245c3 qom: Indent existing code examples
This indents existing code examples that are not indented yet,
just to make future conversion to Sphinx markup easier to review.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200910221526.10041-7-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-30 19:11:36 +02:00
Eduardo Habkost 8814446875 qom: Reformat section titles using Sphinx syntax
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200910221526.10041-6-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-30 19:11:36 +02:00
Eduardo Habkost ed799805d0 qom: Add kernel-doc markup to introduction doc comment
Add DOC: section keyword to introduction doc comment, so it will
be rendered by kernel-doc.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200910221526.10041-5-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-30 19:11:36 +02:00
Eduardo Habkost 78170df827 qom: Use ``code`` Sphinx syntax where appropriate
Replace gtkdoc markup with Sphinx ``code`` syntax.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200910221526.10041-4-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-30 19:11:36 +02:00
Eduardo Habkost 11e1c3addf qom: Use kernel-doc private/public tags in structs
Use kernel-doc syntax for indicating private and public struct
fields.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200910221526.10041-3-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-30 19:11:36 +02:00
Eduardo Habkost 1827c35b6b qom: Document all function parameters in doc comments
kernel-doc requires all function parameters to be documented, so
document them all.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200910221526.10041-2-ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-30 19:11:36 +02:00
Daniel P. Berrangé efba15959c qom: simplify object_find_property / object_class_find_property
When debugging QEMU it is often useful to put a breakpoint on the
error_setg_internal method impl.

Unfortunately the object_property_add / object_class_property_add
methods call object_property_find / object_class_property_find methods
to check if a property exists already before adding the new property.

As a result there are a huge number of calls to error_setg_internal
on startup of most QEMU commands, making it very painful to set a
breakpoint on this method.

Most callers of object_find_property and object_class_find_property,
however, pass in a NULL for the Error parameter. This simplifies the
methods to remove the Error parameter entirely, and then adds some
new wrapper methods that are able to raise an Error when needed.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200914135617.1493072-1-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-22 16:45:16 -04:00
Eduardo Habkost 30b5707c26 qom: Remove module_obj_name parameter from OBJECT_DECLARE* macros
One of the goals of having less boilerplate on QOM declarations
is to avoid human error.  Requiring an extra argument that is
never used is an opportunity for mistakes.

Remove the unused argument from OBJECT_DECLARE_TYPE and
OBJECT_DECLARE_SIMPLE_TYPE.

Coccinelle patch used to convert all users of the macros:

  @@
  declarer name OBJECT_DECLARE_TYPE;
  identifier InstanceType, ClassType, lowercase, UPPERCASE;
  @@
   OBJECT_DECLARE_TYPE(InstanceType, ClassType,
  -                    lowercase,
                       UPPERCASE);

  @@
  declarer name OBJECT_DECLARE_SIMPLE_TYPE;
  identifier InstanceType, lowercase, UPPERCASE;
  @@
   OBJECT_DECLARE_SIMPLE_TYPE(InstanceType,
  -                    lowercase,
                       UPPERCASE);

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Paul Durrant <paul@xen.org>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20200916182519.415636-4-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 14:12:32 -04:00
Eduardo Habkost c734cd40a1 qom: Remove ParentClassType argument from OBJECT_DECLARE_SIMPLE_TYPE
The requirement to specify the parent class type makes the macro
harder to use and easy to misuse (silent bugs can be introduced
if the wrong struct type is specified).

Simplify the macro by just not declaring any class struct,
allowing us to remove the class_size field from the TypeInfo
variables for those types.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200916182519.415636-3-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 14:12:32 -04:00
Richard Henderson 4c880f363e qom: Allow objects to be allocated with increased alignment
It turns out that some hosts have a default malloc alignment less
than that required for vectors.

We assume that, with compiler annotation on CPUArchState, that we
can properly align the vector portion of the guest state.  Fix the
alignment of the allocation by using qemu_memalloc when required.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200916004638.2444147-3-richard.henderson@linaro.org>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 13:59:51 -04:00
Markus Armbruster a21e660777 qom: Correct error values in two contracts
object_property_get_bool()'s contract claims it returns NULL on error.
Pasto; it returns false.

object_property_get_int()'s contract claims it returns "negative".  It
actually returns -1.  All the other object_property_get_FOO()
contracts specify the exact error value, so do the same here.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200917125540.597786-3-armbru@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 13:49:48 -04:00
Markus Armbruster d20f616e8f qom: Clean up object_property_get_enum()'s error value
object_property_get_enum() is the only object_property_FOO() that is
documented to return an undefined value on error.  It does no such
thing, actually: it returns 0 on some errors, and -1 on others.

Needlessly complicated.  Always return -1 on error, and adjust the
contract.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200917125540.597786-2-armbru@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 13:49:48 -04:00
Eduardo Habkost 04dcf4b5db qom: Correct object_class_dynamic_cast_assert() documentation
object_class_dynamic_cast_assert() is not used by
INTERFACE_CHECK, remove misleading mention of that function in
the documentation.

Message-Id: <20200916193101.511600-2-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 13:49:48 -04:00
Eduardo Habkost 8110fa1d94 Use DECLARE_*CHECKER* macros
Generated using:

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=TypeCheckMacro $(git grep -l '' -- '*.[ch]')

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-12-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-13-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-14-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-09 09:27:09 -04:00
Eduardo Habkost db1015e92e Move QOM typedefs and add missing includes
Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.

Patch generated using:

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]')

which will split "typdef struct { ... } TypedefName"
declarations.

Followed by:

 $ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \
    $(git grep -l '' -- '*.[ch]')

which will:
- move the typedefs and #defines above the type check macros
- add missing #include "qom/object.h" lines if necessary

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-09 09:26:43 -04:00
Eduardo Habkost ad09bed1cf qom: Make type checker functions accept const pointers
The existing type check macros all unconditionally drop const
qualifiers from their arguments.  Keep this behavior in the
macros generated by DECLARE_*CHECKER* by now.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200831210740.126168-6-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-08 17:29:19 -04:00
Eduardo Habkost 7808a28f22 qom: DECLARE_*_CHECKERS macros
Sometimes the typedefs are buried inside another header, but
we want to benefit from the automatic definition of type cast
functions.  Introduce macros that will let type checkers be
defined when typedefs are already available.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200831210740.126168-5-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-08 17:29:18 -04:00
Eduardo Habkost 4a5f0545d2 qom: Allow class type name to be specified in OBJECT_DECLARE*
Many QOM types don't follow the Type/TypeClass pattern
on the instance/struct names.  Let the class struct name
be specified in the OBJECT_DECLARE* macros.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200831210740.126168-4-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-08 17:29:18 -04:00
Daniel P. Berrangé f84203a8c2 qom: provide convenient macros for declaring and defining types
When creating new QOM types, there is a lot of boilerplate code that
must be repeated using a standard pattern. This is tedious to write
and liable to suffer from subtle inconsistencies. Thus it would
benefit from some simple automation.

QOM was loosely inspired by GLib's GObject, and indeed GObject suffers
from the same burden of boilerplate code, but has long provided a set of
macros to eliminate this burden in the source implementation. More
recently it has also provided a set of macros to eliminate this burden
in the header declaration.

In GLib there are the G_DECLARE_* and G_DEFINE_* family of macros
for the header declaration and source implementation respectively:

  https://developer.gnome.org/gobject/stable/chapter-gobject.html
  https://developer.gnome.org/gobject/stable/howto-gobject.html

This patch takes inspiration from GObject to provide the equivalent
functionality for QOM.

In the header file, instead of:

    typedef struct MyDevice MyDevice;
    typedef struct MyDeviceClass MyDeviceClass;

    G_DEFINE_AUTOPTR_CLEANUP_FUNC(MyDeviceClass, object_unref)

    #define MY_DEVICE_GET_CLASS(void *obj) \
            OBJECT_GET_CLASS(MyDeviceClass, obj, TYPE_MY_DEVICE)
    #define MY_DEVICE_CLASS(void *klass) \
            OBJECT_CLASS_CHECK(MyDeviceClass, klass, TYPE_MY_DEVICE)
    #define MY_DEVICE(void *obj)
            OBJECT_CHECK(MyDevice, obj, TYPE_MY_DEVICE)

    struct MyDeviceClass {
        DeviceClass parent_class;
    };

We now have

    OBJECT_DECLARE_SIMPLE_TYPE(MyDevice, my_device, MY_DEVICE, DEVICE)

In cases where the class needs some virtual methods, it can be left
to be implemented manually using

    OBJECT_DECLARE_TYPE(MyDevice, my_device, MY_DEVICE)

Note that these macros are including support for g_autoptr() for the
object types, which is something previously only supported for variables
declared as the base Object * type.

Meanwhile in the source file, instead of:

    static void my_device_finalize(Object *obj);
    static void my_device_class_init(ObjectClass *oc, void *data);
    static void my_device_init(Object *obj);

    static const TypeInfo my_device_info = {
        .parent = TYPE_DEVICE,
        .name = TYPE_MY_DEVICE,
        .instance_size = sizeof(MyDevice),
        .instance_init = my_device_init,
        .instance_finalize = my_device_finalize,
        .class_size = sizeof(MyDeviceClass),
        .class_init = my_device_class_init,
    };

    static void
    my_device_register_types(void)
    {
        type_register_static(&my_device_info);
    }
    type_init(my_device_register_types);

We now have

    OBJECT_DEFINE_TYPE(MyDevice, my_device, MY_DEVICE, DEVICE)

Or, if a class needs to implement interfaces:

    OBJECT_DEFINE_TYPE_WITH_INTERFACES(MyDevice, my_device, MY_DEVICE, DEVICE,
                                       { TYPE_USER_CREATABLE }, { NULL })

Or, if a class needs to be abstract

    OBJECT_DEFINE_ABSTRACT_TYPE(MyDevice, my_device, MY_DEVICE, DEVICE)

IOW, in both cases the maintainer now only has to think about the
interesting part of the code which implements useful functionality
and avoids much of the boilerplate.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200723181410.3145233-3-berrange@redhat.com>
[ehabkost: Fix G_DEFINE_AUTOPTR_CLEANUP_FUNC usage]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200831210740.126168-3-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-08 17:29:18 -04:00
Daniel P. Berrangé c5a61e5a3c qom: make object_ref/unref use a void * instead of Object *.
The object_ref/unref methods are intended for use with any subclass of
the base Object. Using "Object *" in the signature is not adding any
meaningful level of type safety, since callers simply use "OBJECT(ptr)"
and this expands to an unchecked cast "(Object *)".

By using "void *" we enable the object_unref() method to be used to
provide support for g_autoptr() with any subclass.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200723181410.3145233-2-berrange@redhat.com>
Message-Id: <20200831210740.126168-2-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-08 17:29:18 -04:00
Markus Armbruster 5bd929d2ff qom: Document object_get_canonical_path() returns malloced string
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200714160202.3121879-5-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-07-21 16:23:43 +02:00
Markus Armbruster 7a309cc95b qom: Change object_get_canonical_path_component() not to malloc
object_get_canonical_path_component() returns a malloced copy of a
property name on success, null on failure.

19 of its 25 callers immediately free the returned copy.

Change object_get_canonical_path_component() to return the property
name directly.  Since modifying the name would be wrong, adjust the
return type to const char *.

Drop the free from the 19 callers become simpler, add the g_strdup()
to the other six.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200714160202.3121879-4-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
2020-07-21 16:23:43 +02:00
Eric Auger db57fef1e2 qom: Introduce object_property_try_add_child()
object_property_add() does not allow object_property_try_add()
to gracefully fail as &error_abort is passed as an error handle.

However such failure can easily be triggered from the QMP shell when,
for instance, one attempts to create an object with an id that already
exists. This is achieved from the following call path:

qmp_object_add -> user_creatable_add_dict -> user_creatable_add_type ->
object_property_add_child -> object_property_add

For instance, from the qmp-shell, call twice:
object-add qom-type=memory-backend-ram id=mem1 props.size=1073741824
and QEMU aborts.

This behavior is undesired as a user/management application mistake
in reusing a property ID shouldn't result in loss of the VM and live
data within.

This patch introduces a new function, object_property_try_add_child()
which takes an error handle and turn object_property_try_add() into
a non-static one.

Now the call path becomes:

user_creatable_add_type -> object_property_try_add_child ->
object_property_try_add

and the error is returned gracefully to the QMP client.

(QEMU) object-add qom-type=memory-backend-ram id=mem2  props.size=4294967296
{"return": {}}
(QEMU) object-add qom-type=memory-backend-ram id=mem2  props.size=4294967296
{"error": {"class": "GenericError", "desc": "attempt to add duplicate property
'mem2' to object (type 'container')"}}

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Fixes: d2623129a7 ("qom: Drop parameter @errp of object_property_add() & friends")
Reviewed-by: Markus Armbruster <armbru@redhat.com>

Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200629193424.30280-2-eric.auger@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-10 18:02:16 -04:00
Markus Armbruster b783f54d60 qom: Make functions taking Error ** return bool, not 0/-1
Just for consistency.  Also fix the example in object_set_props()'s
documentation.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-31-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster 6fd5bef10b qom: Make functions taking Error ** return bool, not void
See recent commit "error: Document Error API usage rules" for
rationale.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-28-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster 5325cc34a2 qom: Put name parameter before value / visitor parameter
The object_property_set_FOO() setters take property name and value in
an unusual order:

    void object_property_set_FOO(Object *obj, FOO_TYPE value,
                                 const char *name, Error **errp)

Having to pass value before name feels grating.  Swap them.

Same for object_property_set(), object_property_get(), and
object_property_parse().

Convert callers with this Coccinelle script:

    @@
    identifier fun = {
        object_property_get, object_property_parse, object_property_set_str,
        object_property_set_link, object_property_set_bool,
        object_property_set_int, object_property_set_uint, object_property_set,
        object_property_set_qobject
    };
    expression obj, v, name, errp;
    @@
    -    fun(obj, v, name, errp)
    +    fun(obj, name, v, errp)

Chokes on hw/arm/musicpal.c's lcd_refresh() with the unhelpful error
message "no position information".  Convert that one manually.

Fails to convert hw/arm/armsse.c, because Coccinelle gets confused by
ARMSSE being used both as typedef and function-like macro there.
Convert manually.

Fails to convert hw/rx/rx-gdbsim.c, because Coccinelle gets confused
by RXCPU being used both as typedef and function-like macro there.
Convert manually.  The other files using RXCPU that way don't need
conversion.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-27-armbru@redhat.com>
[Straightforwad conflict with commit 2336172d9b "audio: set default
value for pcspk.iobase property" resolved]
2020-07-10 15:18:08 +02:00
Markus Armbruster fdb0df8798 qom: Use error_reportf_err() instead of g_printerr() in examples
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-22-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Gerd Hoffmann 0f8198f1b2 object: qom module support
Little helper function to load modules on demand.  In most cases adding
module loading support for devices and other objects is just
s/object_class_by_name/module_object_class_by_name/ in the right spot.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20200624131045.14512-3-kraxel@redhat.com
2020-07-07 14:54:29 +02:00
Markus Armbruster 9fc7fc4d39 qom: Less verbose object_initialize_child()
All users of object_initialize_child() pass the obvious child size
argument.  Almost all pass &error_abort and no properties.  Tiresome.

Rename object_initialize_child() to
object_initialize_child_with_props() to free the name.  New
convenience wrapper object_initialize_child() automates the size
argument, and passes &error_abort and no properties.

Rename object_initialize_childv() to
object_initialize_child_with_propsv() for consistency.

Convert callers with this Coccinelle script:

    @@
    expression parent, propname, type;
    expression child, size;
    symbol error_abort;
    @@
    -    object_initialize_child(parent, propname, OBJECT(child), size, type, &error_abort, NULL)
    +    object_initialize_child(parent, propname, child, size, type, &error_abort, NULL)

    @@
    expression parent, propname, type;
    expression child;
    symbol error_abort;
    @@
    -    object_initialize_child(parent, propname, child, sizeof(*child), type, &error_abort, NULL)
    +    object_initialize_child(parent, propname, child, type)

    @@
    expression parent, propname, type;
    expression child;
    symbol error_abort;
    @@
    -    object_initialize_child(parent, propname, &child, sizeof(child), type, &error_abort, NULL)
    +    object_initialize_child(parent, propname, &child, type)

    @@
    expression parent, propname, type;
    expression child, size, err;
    expression list props;
    @@
    -    object_initialize_child(parent, propname, child, size, type, err, props)
    +    object_initialize_child_with_props(parent, propname, child, size, type, err, props)

Note that Coccinelle chokes on ARMSSE typedef vs. macro in
hw/arm/armsse.c.  Worked around by temporarily renaming the macro for
the spatch run.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
[Rebased: machine opentitan is new (commit fe0fe4735e)]
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-37-armbru@redhat.com>
2020-06-15 22:05:28 +02:00
Markus Armbruster e8512dfa4d qom: Constify object_get_canonical_path{,_component}()'s parameter
Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200527084754.7531-2-armbru@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-06-15 21:34:25 +02:00
Philippe Mathieu-Daudé ca27b5eb7c qom/object: Move Object typedef to 'qemu/typedefs.h'
We use the Object type all over the place.
Forward declare it in "qemu/typedefs.h".

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200504115656.6045-2-f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:36 -04:00
Markus Armbruster df4fe0b291 qom: Drop @errp parameter of object_property_del()
Same story as for object_property_add(): the only way
object_property_del() can fail is when the property with this name
does not exist.  Since our property names are all hardcoded, failure
is a programming error, and the appropriate way to handle it is
passing &error_abort.  Most callers do that, the commit before
previous fixed one that didn't (and got the error handling wrong), and
the two remaining exceptions ignore errors.

Drop the @errp parameter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-19-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-05-15 07:08:14 +02:00
Markus Armbruster d2623129a7 qom: Drop parameter @errp of object_property_add() & friends
The only way object_property_add() can fail is when a property with
the same name already exists.  Since our property names are all
hardcoded, failure is a programming error, and the appropriate way to
handle it is passing &error_abort.

Same for its variants, except for object_property_add_child(), which
additionally fails when the child already has a parent.  Parentage is
also under program control, so this is a programming error, too.

We have a bit over 500 callers.  Almost half of them pass
&error_abort, slightly fewer ignore errors, one test case handles
errors, and the remaining few callers pass them to their own callers.

The previous few commits demonstrated once again that ignoring
programming errors is a bad idea.

Of the few ones that pass on errors, several violate the Error API.
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL.  Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call.  ich9_pm_add_properties(), sparc32_ledma_realize(),
sparc32_dma_realize(), xilinx_axidma_realize(), xilinx_enet_realize()
are wrong that way.

When the one appropriate choice of argument is &error_abort, letting
users pick the argument is a bad idea.

Drop parameter @errp and assert the preconditions instead.

There's one exception to "duplicate property name is a programming
error": the way object_property_add() implements the magic (and
undocumented) "automatic arrayification".  Don't drop @errp there.
Instead, rename object_property_add() to object_property_try_add(),
and add the obvious wrapper object_property_add().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-15-armbru@redhat.com>
[Two semantic rebase conflicts resolved]
2020-05-15 07:07:58 +02:00
Markus Armbruster 7eecec7d12 qom: Drop object_property_set_description() parameter @errp
object_property_set_description() and
object_class_property_set_description() fail only when property @name
is not found.

There are 85 calls of object_property_set_description() and
object_class_property_set_description().  None of them can fail:

* 84 immediately follow the creation of the property.

* The one in spapr_rng_instance_init() refers to a property created in
  spapr_rng_class_init(), from spapr_rng_properties[].

Every one of them still gets to decide what to pass for @errp.

51 calls pass &error_abort, 32 calls pass NULL, one receives the error
and propagates it to &error_abort, and one propagates it to
&error_fatal.  I'm actually surprised none of them violates the Error
API.

What are we gaining by letting callers handle the "property not found"
error?  Use when the property is not known to exist is simpler: you
don't have to guard the call with a check.  We haven't found such a
use in 5+ years.  Until we do, let's make life a bit simpler and drop
the @errp parameter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-8-armbru@redhat.com>
[One semantic rebase conflict resolved]
2020-05-15 07:06:49 +02:00
Markus Armbruster 7025188772 qom: Make all the object_property_add_FOO() return the property
Some object_property_add_FOO() return the newly added property, some
don't.  Clean that up.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-7-armbru@redhat.com>
2020-05-15 06:26:02 +02:00
Markus Armbruster 44a17fe05a qom: Drop convenience method object_property_get_uint16List()
qom/object.c provides object_property_get_TYPE() and
object_property_set_TYPE() for a number of common types.  These are
all convenience wrappers around object_property_get_qobject() and
object_property_set_qobject().

Except for object_property_get_uint16List(), which is unusual in two ways:

* It bypasses object_property_get_qobject().  Fixable; the previous
  commit did it for object_property_get_enum())

* It stores the value through a parameter.  Its contract claims it
  returns the value, like the other functions do.  Also fixable.

Fixing is not worthwhile, though: object_property_get_uint16List() has
seen exactly one user in six years.

Convert the lone user to do its job with the generic
object_property_get_qobject(), and drop object_property_get_uint16List().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200505152926.18877-6-armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
[Commit message typo fixed]
2020-05-15 06:26:02 +02:00