Re: [Qemu-devel] [PATCH 9/9] hw/pci: switch to a generic hotplug handling for PCIDevice

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 20 Jan 2014 13:36:39 +0200
"Michael S. Tsirkin" <mst@redhat.com> wrote:

> On Tue, Jan 14, 2014 at 05:55:54PM +0100, Igor Mammedov wrote:
> > make qdev_unplug()/device_set_realized() to call hotplug handler's
> > plug/unplug methods if available and remove not needed anymore
> > hot(un)plug handling from PCIDevice.
> > 
> > In case if hotplug handler is not available, revert to the legacy
> > hotplug method.
> 
> When isn't it available?
> For buses other than PCI?
For example scsi virtio usb buses.
Paolo said he would convert scsi bus to this interface once series is in.

Eventually all hotluggable buses will/should be converted to new interface
so that we could get rid of legacy implementation.

> 
> > Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> > ---
> > v2:
> >  * fix test-qdev-global-props build failure during "make check"
> > ---
> >  hw/core/qdev.c           |   17 +++++++++++++----
> >  hw/pci/pci.c             |   29 +----------------------------
> >  include/hw/pci/pci.h     |   10 ----------
> >  include/hw/pci/pci_bus.h |    2 --
> >  tests/Makefile           |    2 +-
> >  5 files changed, 15 insertions(+), 45 deletions(-)
> > 
> > diff --git a/hw/core/qdev.c b/hw/core/qdev.c
> > index d8b83f1..3486e5d 100644
> > --- a/hw/core/qdev.c
> > +++ b/hw/core/qdev.c
> > @@ -213,7 +213,6 @@ void qdev_unplug(DeviceState *dev, Error **errp)
> >          error_set(errp, QERR_BUS_NO_HOTPLUG, dev->parent_bus->name);
> >          return;
> >      }
> > -    assert(dc->unplug != NULL);
> >  
> >      if (!dc->hotpluggable) {
> >          error_set(errp, QERR_DEVICE_NO_HOTPLUG,
> > @@ -223,9 +222,13 @@ void qdev_unplug(DeviceState *dev, Error **errp)
> >  
> >      qdev_hot_removed = true;
> >  
> > -    if (dc->unplug(dev) < 0) {
> > -        error_set(errp, QERR_UNDEFINED_ERROR);
> > -        return;
> > +    if (dev->parent_bus && dev->parent_bus->hotplug_handler) {
> > +        hotplug_handler_unplug(dev->parent_bus->hotplug_handler, dev, errp);
> > +    } else {
> > +        assert(dc->unplug != NULL);
> > +        if (dc->unplug(dev) < 0) { /* legacy handler */
> > +            error_set(errp, QERR_UNDEFINED_ERROR);
> > +        }
> >      }
> >  }
> >  
> > @@ -720,6 +723,12 @@ static void device_set_realized(Object *obj, bool value, Error **err)
> >              dc->realize(dev, &local_err);
> >          }
> >  
> > +        if (dev->parent_bus && dev->parent_bus->hotplug_handler &&
> > +            local_err == NULL) {
> > +            hotplug_handler_plug(dev->parent_bus->hotplug_handler,
> > +                                 dev, &local_err);
> > +        }
> > +
> >          if (qdev_get_vmsd(dev) && local_err == NULL) {
> >              vmstate_register_with_alias_id(dev, -1, qdev_get_vmsd(dev), dev,
> >                                             dev->instance_id_alias,
> > diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> > index b8770ef..7e36f29 100644
> > --- a/hw/pci/pci.c
> > +++ b/hw/pci/pci.c
> > @@ -35,6 +35,7 @@
> >  #include "hw/pci/msi.h"
> >  #include "hw/pci/msix.h"
> >  #include "exec/address-spaces.h"
> > +#include "hw/hotplug.h"
> >  
> >  //#define DEBUG_PCI
> >  #ifdef DEBUG_PCI
> > @@ -346,13 +347,6 @@ void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> >      bus->irq_count = g_malloc0(nirq * sizeof(bus->irq_count[0]));
> >  }
> >  
> > -void pci_bus_hotplug(PCIBus *bus, pci_hotplug_fn hotplug, DeviceState *qdev)
> > -{
> > -    bus->qbus.allow_hotplug = 1;
> > -    bus->hotplug = hotplug;
> > -    bus->hotplug_qdev = qdev;
> > -}
> > -
> >  PCIBus *pci_register_bus(DeviceState *parent, const char *name,
> >                           pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> >                           void *irq_opaque,
> > @@ -1750,29 +1744,9 @@ static int pci_qdev_init(DeviceState *qdev)
> >      }
> >      pci_add_option_rom(pci_dev, is_default_rom);
> >  
> > -    if (bus->hotplug) {
> > -        /* Let buses differentiate between hotplug and when device is
> > -         * enabled during qemu machine creation. */
> > -        rc = bus->hotplug(bus->hotplug_qdev, pci_dev,
> > -                          qdev->hotplugged ? PCI_HOTPLUG_ENABLED:
> > -                          PCI_COLDPLUG_ENABLED);
> > -        if (rc != 0) {
> > -            int r = pci_unregister_device(&pci_dev->qdev);
> > -            assert(!r);
> > -            return rc;
> > -        }
> > -    }
> >      return 0;
> >  }
> >  
> > -static int pci_unplug_device(DeviceState *qdev)
> > -{
> > -    PCIDevice *dev = PCI_DEVICE(qdev);
> > -
> > -    return dev->bus->hotplug(dev->bus->hotplug_qdev, dev,
> > -                             PCI_HOTPLUG_DISABLED);
> > -}
> > -
> >  PCIDevice *pci_create_multifunction(PCIBus *bus, int devfn, bool multifunction,
> >                                      const char *name)
> >  {
> > @@ -2243,7 +2217,6 @@ static void pci_device_class_init(ObjectClass *klass, void *data)
> >  {
> >      DeviceClass *k = DEVICE_CLASS(klass);
> >      k->init = pci_qdev_init;
> > -    k->unplug = pci_unplug_device;
> >      k->exit = pci_unregister_device;
> >      k->bus_type = TYPE_PCI_BUS;
> >      k->props = pci_props;
> > diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> > index 03d4bee..c709d62 100644
> > --- a/include/hw/pci/pci.h
> > +++ b/include/hw/pci/pci.h
> > @@ -327,15 +327,6 @@ typedef void (*pci_set_irq_fn)(void *opaque, int irq_num, int level);
> >  typedef int (*pci_map_irq_fn)(PCIDevice *pci_dev, int irq_num);
> >  typedef PCIINTxRoute (*pci_route_irq_fn)(void *opaque, int pin);
> >  
> > -typedef enum {
> > -    PCI_HOTPLUG_DISABLED,
> > -    PCI_HOTPLUG_ENABLED,
> > -    PCI_COLDPLUG_ENABLED,
> > -} PCIHotplugState;
> > -
> > -typedef int (*pci_hotplug_fn)(DeviceState *qdev, PCIDevice *pci_dev,
> > -                              PCIHotplugState state);
> > -
> >  #define TYPE_PCI_BUS "PCI"
> >  #define PCI_BUS(obj) OBJECT_CHECK(PCIBus, (obj), TYPE_PCI_BUS)
> >  #define TYPE_PCIE_BUS "PCIE"
> > @@ -354,7 +345,6 @@ PCIBus *pci_bus_new(DeviceState *parent, const char *name,
> >  void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> >                    void *irq_opaque, int nirq);
> >  int pci_bus_get_irq_level(PCIBus *bus, int irq_num);
> > -void pci_bus_hotplug(PCIBus *bus, pci_hotplug_fn hotplug, DeviceState *dev);
> >  /* 0 <= pin <= 3 0 = INTA, 1 = INTB, 2 = INTC, 3 = INTD */
> >  int pci_swizzle_map_irq_fn(PCIDevice *pci_dev, int pin);
> >  PCIBus *pci_register_bus(DeviceState *parent, const char *name,
> > diff --git a/include/hw/pci/pci_bus.h b/include/hw/pci/pci_bus.h
> > index 9df1788..fabaeee 100644
> > --- a/include/hw/pci/pci_bus.h
> > +++ b/include/hw/pci/pci_bus.h
> > @@ -16,8 +16,6 @@ struct PCIBus {
> >      pci_set_irq_fn set_irq;
> >      pci_map_irq_fn map_irq;
> >      pci_route_irq_fn route_intx_to_irq;
> > -    pci_hotplug_fn hotplug;
> > -    DeviceState *hotplug_qdev;
> >      void *irq_opaque;
> >      PCIDevice *devices[PCI_SLOT_MAX * PCI_FUNC_MAX];
> >      PCIDevice *parent_dev;
> > diff --git a/tests/Makefile b/tests/Makefile
> > index 0aaf657..0bbdecb 100644
> > --- a/tests/Makefile
> > +++ b/tests/Makefile
> > @@ -163,7 +163,7 @@ tests/test-xbzrle$(EXESUF): tests/test-xbzrle.o xbzrle.o page_cache.o libqemuuti
> >  tests/test-cutils$(EXESUF): tests/test-cutils.o util/cutils.o
> >  tests/test-int128$(EXESUF): tests/test-int128.o
> >  tests/test-qdev-global-props$(EXESUF): tests/test-qdev-global-props.o \
> > -	hw/core/qdev.o hw/core/qdev-properties.o \
> > +	hw/core/qdev.o hw/core/qdev-properties.o hw/core/hotplug.o\
> >  	hw/core/irq.o \
> >  	$(qom-core-obj) \
> >  	$(test-qapi-obj-y) \
> > -- 
> > 1.7.1
>