isa: Clean up use of cannot_instantiate_with_device_add_yet

Drop it when there's no obvious reason why device_add could not work.
Else keep and document why.

* isa-fdc: drop

* i8042: drop, even though its I/O base is hardcoded (because you
  could conceivably still add one to a board that has none), and even
  though PC board code wires up the A20 line (because that wiring is
  optional)

* port92: keep because it needs additional wiring by port92_init()

* mc146818rtc: keep because it needs to be wired up by rtc_init()

* m48t59_isa: keep because needs to be wired up by m48t59_init_isa()

* isa-pit, kvm-pit: keep (in their abstract base pic-common) because
  the PIT needs additional wiring by board code, depending on HPET
  presence

* pcspk: keep because of pointer property pit, and because realize
  sets global pcspk_state

* vmmouse: keep because of pointer property ps2_mouse

* vmport: keep because realize sets global port_state

* isa-i8259, kvm-i8259: keep (in their abstract base pic-common),
  because the PICs' IRQ input lines are set up by board code, and the
  wiring of the slave to the master is hard-coded in device model code

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qdev: Do not let the user try to device_add when it cannot work

Such devices have always been unavailable and omitted from the list of
available devices shown by device_add help.  Until commit 18b6dad
silently broke the former, setting up nasty traps for unwary users,
like this one:

    $ qemu-system-x86_64 -nodefaults -monitor stdio -display none
    QEMU 1.6.50 monitor - type 'help' for more information
    (qemu) device_add apic
    Segmentation fault (core dumped)

I call that a regression.  Fix it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qdev-monitor: device_add crashes on non-device driver name, fix

Watch this:

    $ upstream-qemu -nodefaults -S -display none -monitor stdio
    QEMU 1.7.50 monitor - type 'help' for more information
    (qemu) device_add rng-egd
    /work/armbru/qemu/qdev-monitor.c:491:qdev_device_add: Object 0x2089b00 is not an instance of type device
    Aborted (core dumped)

Crashes because "rng-egd" exists, but isn't a subtype of TYPE_DEVICE.
Broken in commit 18b6dad.

Cc: qemu-stable@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
hw: cannot_instantiate_with_device_add_yet due to pointer props

Pointer properties can be set only by code, not by device_add.  A
device with a pointer property can work with device_add only when the
property may remain null.

This is the case for property "interrupt_vector" of device
"etraxfs,pic".  Add a comment there.

Set cannot_instantiate_with_device_add_yet for the other devices with
pointer properties, with a comment explaining why.

Juha Riihimäki and Peter Maydell deserve my thanks for making "pointer
property must not remain null" blatantly obvious in the OMAP devices.

Only device "smbus-eeprom" is actually changed.  The others are all
sysbus devices, which get cannot_instantiate_with_device_add_yet set
in their abstract base's class init function.  Setting it again in
their class init function is technically redundant, but serves as
insurance for when sysbus devices become available with device_add,
and as documentation.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@gmail.com> (for ETRAX)
Signed-off-by: Andreas Färber <afaerber@suse.de>
qdev: Document that pointer properties kill device_add

Ask users of DEFINE_PROP_PTR() to set
cannot_instantiate_with_device_add_yet, or explain why it's not
needed.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qom: Split out object and class caches

The object-cast and class-cast caches cannot be shared because class
caching is conditional on the target type not being an interface and
object caching is unconditional. Leads to a bug when a class cast
to an interface follows an object cast to the same interface type:

FooObject = FOO(obj);
FooClass = FOO_GET_CLASS(obj);

Where TYPE_FOO is an interface. The first (object) cast will be
successful and cache the casting result (i.e. TYPE_FOO will be cached).
The second (class) cast will then check the shared cast cache
and register a hit. The issue is, when a class cast hits in the cache
it just returns a pointer cast of the input class (i.e. the concrete
class).

When casting to an interface, the cast itself must return the
interface class, not the concrete class. The implementation of class
cast caching already ensures that the returned cast result is only
a pointer cast before caching. The object cast logic however does
not have this check.

Resolve by just splitting the object and class caches.

Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Nathan Rossi <nathan.rossi@xilinx.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qom: Do not register interface "types" in the type table

There should be no need to look them up nor enumerate the interface
"types", whose "classes" are really just vtables.  Just create the
types and add them to the interface list of the parent type.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qom: Detect bad reentrance during object_class_foreach()

We should not modify the type hash table while it is being iterated on.
Assert that it does not happen.

Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qdev: Drop misleading qbus_free() function

Same reasoning as commit 02a5c4c97422b40034f31265e0f139f7846172a8
("qdev: Drop misleading qdev_free() function").  The qbus_free()
function removes the child from the namespace and decrements the
reference count.  It does not, however, guarantee to free the child
since the refcount may still be held.

Just call object_unparent() directly.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
apic: Cleanup for QOM'ification

Do some cleanup, including:
1. Remove DO_UPCAST() for APICCommonState
2. Change DeviceState pointers from 'd' to 'dev', better to understand
3. Rename 'register_types' to specifically 'apic_common_register_types'

Signed-off-by: xiaoqiang zhao <zxq_yx_007@163.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
apic: QOM'ify APIC

Convert 'init' function to QOM's 'realize' for apic, kvm/apic and
xen/xen_apic.

Signed-off-by: xiaoqiang zhao <zxq_yx_007@163.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
icc_bus: QOM'ify ICC

For consistency, QOM'ify APIC's parent bus.

Signed-off-by: xiaoqiang zhao <zxq_yx_007@163.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
ioapic: Cleanup for QOM'ification

Some cleanups:
* ioapic_common.c: Rename 'register_types' to 'ioapic_common_register_types'
* Replace inline 'DEVICE(s)' with local 'DeviceState *dev' variable

Signed-off-by: xiaoqiang zhao <zxq_yx_007@163.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
ioapic: QOM'ify ioapic

Convert 'init' function to QOM's 'realize' for ioapic and kvm-ioapic.
Change variable 'ioapic_no' from static to global. Then we can drop
the 'instance_no' function argument.

Signed-off-by: xiaoqiang zhao <zxq_yx_007@163.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>