qom: Make object_child_foreach() safe for objects removal

Current object_child_foreach() uses QTAILQ_FOREACH() to walk
through children and that makes children removal from the callback
impossible.

This makes object_child_foreach() use QTAILQ_FOREACH_SAFE().

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
machine: Clean up -machine handling

Since commit c4090f8, -object options are no longer handled through
object_set_property(), so clean up -object leftovers by renaming the
function and dropping special-casing of qom-type and id properties.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qom: Add automatic arrayification to object_property_add()

If "[*]" is given as the last part of a QOM property name, treat that
as an array property. The added property is given the first available
name, replacing the * with a decimal number counting from 0.

First add with name "foo[*]" will be "foo[0]". Second "foo[1]" and so
on.

Callers may inspect the ObjectProperty * return value to see what
number the added property was given.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
memory: Remove object_property_add_child_array()

Obsoleted by automatic object_property_add() arrayification.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qdev: Use error_abort instead of using local_err

This error can not happen normally. If it happens, it indicates
something very wrong, we should abort QEMU. Moreover, the
user can only refer to /machine/peripheral or /objects, not
/machine/unattached.

While at it, remove superfluous check about local_err.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qdev: Use NULL instead of local_err for qbus_child unrealize

Forcefully unrealize all children regardless of errors in earlier
iterations (if any). We should keep going with cleanup operation
rather than report an error immediately. Therefore store the first
child unrealization failure and propagate it at the end. We also
forcefully unregister vmsd and unrealize actual object, too.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Andreas Färber <afaerber@suse.de>
qdev: Add cleanup logic in device_set_realized() to avoid resource leak

At present, this function doesn't have partial cleanup implemented,
which will cause resource leaks in some scenarios.

Example:

1. Assume that "dc->realize(dev, &local_err)" executes successful
   and local_err == NULL;
2. device hotplug in hotplug_handler_plug() executes but fails
   (it is prone to occur). Then local_err != NULL;
3. error_propagate(errp, local_err) and return. But the resources
   which have been allocated in dc->realize() will be leaked.
Simple backtrace:
  dc->realize()
   |->device_realize
            |->pci_qdev_init()
                |->do_pci_register_device()
                |->etc.

Add fuller cleanup logic which assures that function can
goto appropriate error label as local_err population is
detected at each relevant point.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Andreas Färber <afaerber@suse.de>
Merge remote-tracking branch 'remotes/afaerber/tags/qom-devices-for-peter' into staging

QOM infrastructure fixes and device conversions

* Cleanups for recursive device unrealization

# gpg: Signature made Thu 04 Sep 2014 18:17:35 BST using RSA key ID 3E7E013F
# gpg: Good signature from "Andreas Färber <afaerber@suse.de>"
# gpg:                 aka "Andreas Färber <afaerber@suse.com>"

* remotes/afaerber/tags/qom-devices-for-peter:
  qdev: Add cleanup logic in device_set_realized() to avoid resource leak
  qdev: Use NULL instead of local_err for qbus_child unrealize
  qdev: Use error_abort instead of using local_err
  memory: Remove object_property_add_child_array()
  qom: Add automatic arrayification to object_property_add()
  machine: Clean up -machine handling
  qom: Make object_child_foreach() safe for objects removal

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>