[0/5] qom: module loading cleanups

Message

Paolo Bonzini Oct. 29, 2024, 12:26 p.m. UTC

While looking at possible Rust APIs for object_new/qdev_new (one of the
functions that rust/hw/char/pl011 uses via FFI) I noticed that the support
for modules in QOM APIs is quite random.

In particular, loading modules is done by object_initialize() and
qdev_new(), but not by object_new(); furthermore, the loading code is
duplicated between object_initialize() and module_object_class_by_name().
This series fixes that.

Patches 1-2 are small cleanups.

Patches 3-4 let object_new() use a module if the type is not present,
like object_initialize() already does.  To get there, all calls to
type_get_by_name() are changed to either type_get_by_name_noload() (the
old function) or type_get_or_load_by_name() (which looks at modules
like object_initialize() and module_object_class_by_name() do).

This is enough to let Rust code use a single function object_new() to create
QOM objects; the function can be wrapped to allow writing something like
"PL011State::new()" instead of object_new(TYPE_PL011) as *mut PL011State".

Patch 5 finally allows modularized user-creatable classes, which are
not allowed just because the code uses the non-module-friendly
object_class_by_name().  While there are no modularized user-creatable
classes right now, there is no real difference between them and
character devices (which do allow modularization).  This patch could
be left out if desired.

Paolo


Paolo Bonzini (5):
  qom: remove unused function
  qom: use object_new_with_class when possible
  qom: centralize module-loading functionality
  qom: let object_new use a module if the type is not present
  qom: allow user-creatable classes to be in modules

 include/qom/object.h    |  8 -----
 hw/core/qdev.c          | 21 ++---------
 qom/object.c            | 80 +++++++++++++++++++----------------------
 qom/object_interfaces.c |  4 +--
 qom/qom-qmp-cmds.c      |  4 +--
 5 files changed, 43 insertions(+), 74 deletions(-)

Comments

Richard Henderson Oct. 29, 2024, 5:05 p.m. UTC | #1

On 10/29/24 12:26, Paolo Bonzini wrote:
> Paolo Bonzini (5):
>    qom: remove unused function
>    qom: use object_new_with_class when possible
>    qom: centralize module-loading functionality
>    qom: let object_new use a module if the type is not present
>    qom: allow user-creatable classes to be in modules

Reviewed-by: Richard Henderson <[e-mail]>

r~