[Qemu-devel] [PATCH 03/15] pci: allow cleanup/unregistration of PCI root buses

Greg Kurz posted 15 patches 6 years, 10 months ago
There is a newer version of this series
[Qemu-devel] [PATCH 03/15] pci: allow cleanup/unregistration of PCI root buses
Posted by Greg Kurz 6 years, 10 months ago
From: Michael Roth <mdroth@linux.vnet.ibm.com>

This adds cleanup counterparts to pci_register_root_bus(),
pci_root_bus_new(), and pci_bus_irqs().

These cleanup routines are needed in the case of hotpluggable
PCIHostBridge implementations. Currently we can rely on the
object_unparent()'ing of the PCIHostState recursively unparenting
and cleaning up it's child buses, but we need explicit calls
to also:

  1) remove the PCIHostState from pci_host_bridges global list.
     otherwise, we risk accessing freed memory when we access
     the list later
  2) clean up memory allocated in pci_bus_irqs()

Both are handled outside the context of any particular bus or
host bridge's init/realize functions, making it difficult to
avoid the need for explicit cleanup functions without remodeling
how PCIHostBridges are created. So keep it simple and just add
them for now.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Greg Kurz <groug@kaod.org>
---
 hw/pci/pci.c         |   33 +++++++++++++++++++++++++++++++++
 include/hw/pci/pci.h |    3 +++
 2 files changed, 36 insertions(+)

diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index efb5ce196ffb..16354f91206c 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -333,6 +333,13 @@ static void pci_host_bus_register(DeviceState *host)
     QLIST_INSERT_HEAD(&pci_host_bridges, host_bridge, next);
 }
 
+static void pci_host_bus_unregister(DeviceState *host)
+{
+    PCIHostState *host_bridge = PCI_HOST_BRIDGE(host);
+
+    QLIST_REMOVE(host_bridge, next);
+}
+
 PCIBus *pci_device_root_bus(const PCIDevice *d)
 {
     PCIBus *bus = pci_get_bus(d);
@@ -379,6 +386,11 @@ static void pci_root_bus_init(PCIBus *bus, DeviceState *parent,
     pci_host_bus_register(parent);
 }
 
+static void pci_bus_uninit(PCIBus *bus)
+{
+    pci_host_bus_unregister(BUS(bus)->parent);
+}
+
 bool pci_bus_is_express(PCIBus *bus)
 {
     return object_dynamic_cast(OBJECT(bus), TYPE_PCIE_BUS);
@@ -413,6 +425,12 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
     return bus;
 }
 
+void pci_root_bus_cleanup(PCIBus *bus)
+{
+    pci_bus_uninit(bus);
+    object_unparent(OBJECT(bus));
+}
+
 void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
                   void *irq_opaque, int nirq)
 {
@@ -423,6 +441,15 @@ 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_irqs_cleanup(PCIBus *bus)
+{
+    bus->set_irq = NULL;
+    bus->map_irq = NULL;
+    bus->irq_opaque = NULL;
+    bus->nirq = 0;
+    g_free(bus->irq_count);
+}
+
 PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
                               pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
                               void *irq_opaque,
@@ -439,6 +466,12 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
     return bus;
 }
 
+void pci_unregister_root_bus(PCIBus *bus)
+{
+    pci_bus_irqs_cleanup(bus);
+    pci_root_bus_cleanup(bus);
+}
+
 int pci_bus_num(PCIBus *s)
 {
     return PCI_BUS_GET_CLASS(s)->bus_num(s);
diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index e6514bba23aa..8998e3be3390 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -405,8 +405,10 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
                          MemoryRegion *address_space_mem,
                          MemoryRegion *address_space_io,
                          uint8_t devfn_min, const char *typename);
+void pci_root_bus_cleanup(PCIBus *bus);
 void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
                   void *irq_opaque, int nirq);
+void pci_bus_irqs_cleanup(PCIBus *bus);
 int pci_bus_get_irq_level(PCIBus *bus, int irq_num);
 /* 0 <= pin <= 3 0 = INTA, 1 = INTB, 2 = INTC, 3 = INTD */
 int pci_swizzle_map_irq_fn(PCIDevice *pci_dev, int pin);
@@ -417,6 +419,7 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
                               MemoryRegion *address_space_io,
                               uint8_t devfn_min, int nirq,
                               const char *typename);
+void pci_unregister_root_bus(PCIBus *bus);
 void pci_bus_set_route_irq_fn(PCIBus *, pci_route_irq_fn);
 PCIINTxRoute pci_device_route_intx_to_irq(PCIDevice *dev, int pin);
 bool pci_intx_route_changed(PCIINTxRoute *old, PCIINTxRoute *new);


Re: [Qemu-devel] [PATCH 03/15] pci: allow cleanup/unregistration of PCI root buses
Posted by Michael S. Tsirkin 6 years, 10 months ago
On Fri, Dec 21, 2018 at 01:35:30AM +0100, Greg Kurz wrote:
> From: Michael Roth <mdroth@linux.vnet.ibm.com>
> 
> This adds cleanup counterparts to pci_register_root_bus(),
> pci_root_bus_new(), and pci_bus_irqs().
> 
> These cleanup routines are needed in the case of hotpluggable
> PCIHostBridge implementations. Currently we can rely on the
> object_unparent()'ing of the PCIHostState recursively unparenting
> and cleaning up it's child buses, but we need explicit calls
> to also:
> 
>   1) remove the PCIHostState from pci_host_bridges global list.
>      otherwise, we risk accessing freed memory when we access
>      the list later
>   2) clean up memory allocated in pci_bus_irqs()
> 
> Both are handled outside the context of any particular bus or
> host bridge's init/realize functions, making it difficult to
> avoid the need for explicit cleanup functions without remodeling
> how PCIHostBridges are created. So keep it simple and just add
> them for now.
> 
> Cc: Michael S. Tsirkin <mst@redhat.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> Signed-off-by: Greg Kurz <groug@kaod.org>

Reviewed-by: Michael S. Tsirkin <mst@redhat.com>

> ---
>  hw/pci/pci.c         |   33 +++++++++++++++++++++++++++++++++
>  include/hw/pci/pci.h |    3 +++
>  2 files changed, 36 insertions(+)
> 
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index efb5ce196ffb..16354f91206c 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -333,6 +333,13 @@ static void pci_host_bus_register(DeviceState *host)
>      QLIST_INSERT_HEAD(&pci_host_bridges, host_bridge, next);
>  }
>  
> +static void pci_host_bus_unregister(DeviceState *host)
> +{
> +    PCIHostState *host_bridge = PCI_HOST_BRIDGE(host);
> +
> +    QLIST_REMOVE(host_bridge, next);
> +}
> +
>  PCIBus *pci_device_root_bus(const PCIDevice *d)
>  {
>      PCIBus *bus = pci_get_bus(d);
> @@ -379,6 +386,11 @@ static void pci_root_bus_init(PCIBus *bus, DeviceState *parent,
>      pci_host_bus_register(parent);
>  }
>  
> +static void pci_bus_uninit(PCIBus *bus)
> +{
> +    pci_host_bus_unregister(BUS(bus)->parent);
> +}
> +
>  bool pci_bus_is_express(PCIBus *bus)
>  {
>      return object_dynamic_cast(OBJECT(bus), TYPE_PCIE_BUS);
> @@ -413,6 +425,12 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
>      return bus;
>  }
>  
> +void pci_root_bus_cleanup(PCIBus *bus)
> +{
> +    pci_bus_uninit(bus);
> +    object_unparent(OBJECT(bus));
> +}
> +
>  void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
>                    void *irq_opaque, int nirq)
>  {
> @@ -423,6 +441,15 @@ 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_irqs_cleanup(PCIBus *bus)
> +{
> +    bus->set_irq = NULL;
> +    bus->map_irq = NULL;
> +    bus->irq_opaque = NULL;
> +    bus->nirq = 0;
> +    g_free(bus->irq_count);
> +}
> +
>  PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
>                                pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
>                                void *irq_opaque,
> @@ -439,6 +466,12 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
>      return bus;
>  }
>  
> +void pci_unregister_root_bus(PCIBus *bus)
> +{
> +    pci_bus_irqs_cleanup(bus);
> +    pci_root_bus_cleanup(bus);
> +}
> +
>  int pci_bus_num(PCIBus *s)
>  {
>      return PCI_BUS_GET_CLASS(s)->bus_num(s);
> diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> index e6514bba23aa..8998e3be3390 100644
> --- a/include/hw/pci/pci.h
> +++ b/include/hw/pci/pci.h
> @@ -405,8 +405,10 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
>                           MemoryRegion *address_space_mem,
>                           MemoryRegion *address_space_io,
>                           uint8_t devfn_min, const char *typename);
> +void pci_root_bus_cleanup(PCIBus *bus);
>  void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
>                    void *irq_opaque, int nirq);
> +void pci_bus_irqs_cleanup(PCIBus *bus);
>  int pci_bus_get_irq_level(PCIBus *bus, int irq_num);
>  /* 0 <= pin <= 3 0 = INTA, 1 = INTB, 2 = INTC, 3 = INTD */
>  int pci_swizzle_map_irq_fn(PCIDevice *pci_dev, int pin);
> @@ -417,6 +419,7 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
>                                MemoryRegion *address_space_io,
>                                uint8_t devfn_min, int nirq,
>                                const char *typename);
> +void pci_unregister_root_bus(PCIBus *bus);
>  void pci_bus_set_route_irq_fn(PCIBus *, pci_route_irq_fn);
>  PCIINTxRoute pci_device_route_intx_to_irq(PCIDevice *dev, int pin);
>  bool pci_intx_route_changed(PCIINTxRoute *old, PCIINTxRoute *new);

Re: [Qemu-devel] [PATCH 03/15] pci: allow cleanup/unregistration of PCI root buses
Posted by David Gibson 6 years, 10 months ago
On Fri, Dec 21, 2018 at 11:19:18AM -0500, Michael S. Tsirkin wrote:
> On Fri, Dec 21, 2018 at 01:35:30AM +0100, Greg Kurz wrote:
> > From: Michael Roth <mdroth@linux.vnet.ibm.com>
> > 
> > This adds cleanup counterparts to pci_register_root_bus(),
> > pci_root_bus_new(), and pci_bus_irqs().
> > 
> > These cleanup routines are needed in the case of hotpluggable
> > PCIHostBridge implementations. Currently we can rely on the
> > object_unparent()'ing of the PCIHostState recursively unparenting
> > and cleaning up it's child buses, but we need explicit calls
> > to also:
> > 
> >   1) remove the PCIHostState from pci_host_bridges global list.
> >      otherwise, we risk accessing freed memory when we access
> >      the list later
> >   2) clean up memory allocated in pci_bus_irqs()
> > 
> > Both are handled outside the context of any particular bus or
> > host bridge's init/realize functions, making it difficult to
> > avoid the need for explicit cleanup functions without remodeling
> > how PCIHostBridges are created. So keep it simple and just add
> > them for now.
> > 
> > Cc: Michael S. Tsirkin <mst@redhat.com>
> > Cc: Paolo Bonzini <pbonzini@redhat.com>
> > Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> > Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> > Signed-off-by: Greg Kurz <groug@kaod.org>
> 
> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>

I've applied this tentatively to ppc-for-4.0.  Let me know, Michael,
if you'd prefer to take it through your tree.

> 
> > ---
> >  hw/pci/pci.c         |   33 +++++++++++++++++++++++++++++++++
> >  include/hw/pci/pci.h |    3 +++
> >  2 files changed, 36 insertions(+)
> > 
> > diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> > index efb5ce196ffb..16354f91206c 100644
> > --- a/hw/pci/pci.c
> > +++ b/hw/pci/pci.c
> > @@ -333,6 +333,13 @@ static void pci_host_bus_register(DeviceState *host)
> >      QLIST_INSERT_HEAD(&pci_host_bridges, host_bridge, next);
> >  }
> >  
> > +static void pci_host_bus_unregister(DeviceState *host)
> > +{
> > +    PCIHostState *host_bridge = PCI_HOST_BRIDGE(host);
> > +
> > +    QLIST_REMOVE(host_bridge, next);
> > +}
> > +
> >  PCIBus *pci_device_root_bus(const PCIDevice *d)
> >  {
> >      PCIBus *bus = pci_get_bus(d);
> > @@ -379,6 +386,11 @@ static void pci_root_bus_init(PCIBus *bus, DeviceState *parent,
> >      pci_host_bus_register(parent);
> >  }
> >  
> > +static void pci_bus_uninit(PCIBus *bus)
> > +{
> > +    pci_host_bus_unregister(BUS(bus)->parent);
> > +}
> > +
> >  bool pci_bus_is_express(PCIBus *bus)
> >  {
> >      return object_dynamic_cast(OBJECT(bus), TYPE_PCIE_BUS);
> > @@ -413,6 +425,12 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
> >      return bus;
> >  }
> >  
> > +void pci_root_bus_cleanup(PCIBus *bus)
> > +{
> > +    pci_bus_uninit(bus);
> > +    object_unparent(OBJECT(bus));
> > +}
> > +
> >  void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> >                    void *irq_opaque, int nirq)
> >  {
> > @@ -423,6 +441,15 @@ 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_irqs_cleanup(PCIBus *bus)
> > +{
> > +    bus->set_irq = NULL;
> > +    bus->map_irq = NULL;
> > +    bus->irq_opaque = NULL;
> > +    bus->nirq = 0;
> > +    g_free(bus->irq_count);
> > +}
> > +
> >  PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
> >                                pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> >                                void *irq_opaque,
> > @@ -439,6 +466,12 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
> >      return bus;
> >  }
> >  
> > +void pci_unregister_root_bus(PCIBus *bus)
> > +{
> > +    pci_bus_irqs_cleanup(bus);
> > +    pci_root_bus_cleanup(bus);
> > +}
> > +
> >  int pci_bus_num(PCIBus *s)
> >  {
> >      return PCI_BUS_GET_CLASS(s)->bus_num(s);
> > diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> > index e6514bba23aa..8998e3be3390 100644
> > --- a/include/hw/pci/pci.h
> > +++ b/include/hw/pci/pci.h
> > @@ -405,8 +405,10 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
> >                           MemoryRegion *address_space_mem,
> >                           MemoryRegion *address_space_io,
> >                           uint8_t devfn_min, const char *typename);
> > +void pci_root_bus_cleanup(PCIBus *bus);
> >  void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> >                    void *irq_opaque, int nirq);
> > +void pci_bus_irqs_cleanup(PCIBus *bus);
> >  int pci_bus_get_irq_level(PCIBus *bus, int irq_num);
> >  /* 0 <= pin <= 3 0 = INTA, 1 = INTB, 2 = INTC, 3 = INTD */
> >  int pci_swizzle_map_irq_fn(PCIDevice *pci_dev, int pin);
> > @@ -417,6 +419,7 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
> >                                MemoryRegion *address_space_io,
> >                                uint8_t devfn_min, int nirq,
> >                                const char *typename);
> > +void pci_unregister_root_bus(PCIBus *bus);
> >  void pci_bus_set_route_irq_fn(PCIBus *, pci_route_irq_fn);
> >  PCIINTxRoute pci_device_route_intx_to_irq(PCIDevice *dev, int pin);
> >  bool pci_intx_route_changed(PCIINTxRoute *old, PCIINTxRoute *new);
> 

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson
Re: [Qemu-devel] [PATCH 03/15] pci: allow cleanup/unregistration of PCI root buses
Posted by Michael S. Tsirkin 6 years, 10 months ago
On Thu, Jan 03, 2019 at 11:36:33AM +1100, David Gibson wrote:
> On Fri, Dec 21, 2018 at 11:19:18AM -0500, Michael S. Tsirkin wrote:
> > On Fri, Dec 21, 2018 at 01:35:30AM +0100, Greg Kurz wrote:
> > > From: Michael Roth <mdroth@linux.vnet.ibm.com>
> > > 
> > > This adds cleanup counterparts to pci_register_root_bus(),
> > > pci_root_bus_new(), and pci_bus_irqs().
> > > 
> > > These cleanup routines are needed in the case of hotpluggable
> > > PCIHostBridge implementations. Currently we can rely on the
> > > object_unparent()'ing of the PCIHostState recursively unparenting
> > > and cleaning up it's child buses, but we need explicit calls
> > > to also:
> > > 
> > >   1) remove the PCIHostState from pci_host_bridges global list.
> > >      otherwise, we risk accessing freed memory when we access
> > >      the list later
> > >   2) clean up memory allocated in pci_bus_irqs()
> > > 
> > > Both are handled outside the context of any particular bus or
> > > host bridge's init/realize functions, making it difficult to
> > > avoid the need for explicit cleanup functions without remodeling
> > > how PCIHostBridges are created. So keep it simple and just add
> > > them for now.
> > > 
> > > Cc: Michael S. Tsirkin <mst@redhat.com>
> > > Cc: Paolo Bonzini <pbonzini@redhat.com>
> > > Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> > > Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> > > Signed-off-by: Greg Kurz <groug@kaod.org>
> > 
> > Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> 
> I've applied this tentatively to ppc-for-4.0.  Let me know, Michael,
> if you'd prefer to take it through your tree.


I think your tree makes sense for this.

> > 
> > > ---
> > >  hw/pci/pci.c         |   33 +++++++++++++++++++++++++++++++++
> > >  include/hw/pci/pci.h |    3 +++
> > >  2 files changed, 36 insertions(+)
> > > 
> > > diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> > > index efb5ce196ffb..16354f91206c 100644
> > > --- a/hw/pci/pci.c
> > > +++ b/hw/pci/pci.c
> > > @@ -333,6 +333,13 @@ static void pci_host_bus_register(DeviceState *host)
> > >      QLIST_INSERT_HEAD(&pci_host_bridges, host_bridge, next);
> > >  }
> > >  
> > > +static void pci_host_bus_unregister(DeviceState *host)
> > > +{
> > > +    PCIHostState *host_bridge = PCI_HOST_BRIDGE(host);
> > > +
> > > +    QLIST_REMOVE(host_bridge, next);
> > > +}
> > > +
> > >  PCIBus *pci_device_root_bus(const PCIDevice *d)
> > >  {
> > >      PCIBus *bus = pci_get_bus(d);
> > > @@ -379,6 +386,11 @@ static void pci_root_bus_init(PCIBus *bus, DeviceState *parent,
> > >      pci_host_bus_register(parent);
> > >  }
> > >  
> > > +static void pci_bus_uninit(PCIBus *bus)
> > > +{
> > > +    pci_host_bus_unregister(BUS(bus)->parent);
> > > +}
> > > +
> > >  bool pci_bus_is_express(PCIBus *bus)
> > >  {
> > >      return object_dynamic_cast(OBJECT(bus), TYPE_PCIE_BUS);
> > > @@ -413,6 +425,12 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
> > >      return bus;
> > >  }
> > >  
> > > +void pci_root_bus_cleanup(PCIBus *bus)
> > > +{
> > > +    pci_bus_uninit(bus);
> > > +    object_unparent(OBJECT(bus));
> > > +}
> > > +
> > >  void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> > >                    void *irq_opaque, int nirq)
> > >  {
> > > @@ -423,6 +441,15 @@ 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_irqs_cleanup(PCIBus *bus)
> > > +{
> > > +    bus->set_irq = NULL;
> > > +    bus->map_irq = NULL;
> > > +    bus->irq_opaque = NULL;
> > > +    bus->nirq = 0;
> > > +    g_free(bus->irq_count);
> > > +}
> > > +
> > >  PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
> > >                                pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> > >                                void *irq_opaque,
> > > @@ -439,6 +466,12 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
> > >      return bus;
> > >  }
> > >  
> > > +void pci_unregister_root_bus(PCIBus *bus)
> > > +{
> > > +    pci_bus_irqs_cleanup(bus);
> > > +    pci_root_bus_cleanup(bus);
> > > +}
> > > +
> > >  int pci_bus_num(PCIBus *s)
> > >  {
> > >      return PCI_BUS_GET_CLASS(s)->bus_num(s);
> > > diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> > > index e6514bba23aa..8998e3be3390 100644
> > > --- a/include/hw/pci/pci.h
> > > +++ b/include/hw/pci/pci.h
> > > @@ -405,8 +405,10 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
> > >                           MemoryRegion *address_space_mem,
> > >                           MemoryRegion *address_space_io,
> > >                           uint8_t devfn_min, const char *typename);
> > > +void pci_root_bus_cleanup(PCIBus *bus);
> > >  void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> > >                    void *irq_opaque, int nirq);
> > > +void pci_bus_irqs_cleanup(PCIBus *bus);
> > >  int pci_bus_get_irq_level(PCIBus *bus, int irq_num);
> > >  /* 0 <= pin <= 3 0 = INTA, 1 = INTB, 2 = INTC, 3 = INTD */
> > >  int pci_swizzle_map_irq_fn(PCIDevice *pci_dev, int pin);
> > > @@ -417,6 +419,7 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
> > >                                MemoryRegion *address_space_io,
> > >                                uint8_t devfn_min, int nirq,
> > >                                const char *typename);
> > > +void pci_unregister_root_bus(PCIBus *bus);
> > >  void pci_bus_set_route_irq_fn(PCIBus *, pci_route_irq_fn);
> > >  PCIINTxRoute pci_device_route_intx_to_irq(PCIDevice *dev, int pin);
> > >  bool pci_intx_route_changed(PCIINTxRoute *old, PCIINTxRoute *new);
> > 
> 
> -- 
> David Gibson			| I'll have my music baroque, and my code
> david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
> 				| _way_ _around_!
> http://www.ozlabs.org/~dgibson



Re: [Qemu-devel] [PATCH 03/15] pci: allow cleanup/unregistration of PCI root buses
Posted by David Gibson 6 years, 10 months ago
On Wed, Jan 02, 2019 at 10:27:14PM -0500, Michael S. Tsirkin wrote:
> On Thu, Jan 03, 2019 at 11:36:33AM +1100, David Gibson wrote:
> > On Fri, Dec 21, 2018 at 11:19:18AM -0500, Michael S. Tsirkin wrote:
> > > On Fri, Dec 21, 2018 at 01:35:30AM +0100, Greg Kurz wrote:
> > > > From: Michael Roth <mdroth@linux.vnet.ibm.com>
> > > > 
> > > > This adds cleanup counterparts to pci_register_root_bus(),
> > > > pci_root_bus_new(), and pci_bus_irqs().
> > > > 
> > > > These cleanup routines are needed in the case of hotpluggable
> > > > PCIHostBridge implementations. Currently we can rely on the
> > > > object_unparent()'ing of the PCIHostState recursively unparenting
> > > > and cleaning up it's child buses, but we need explicit calls
> > > > to also:
> > > > 
> > > >   1) remove the PCIHostState from pci_host_bridges global list.
> > > >      otherwise, we risk accessing freed memory when we access
> > > >      the list later
> > > >   2) clean up memory allocated in pci_bus_irqs()
> > > > 
> > > > Both are handled outside the context of any particular bus or
> > > > host bridge's init/realize functions, making it difficult to
> > > > avoid the need for explicit cleanup functions without remodeling
> > > > how PCIHostBridges are created. So keep it simple and just add
> > > > them for now.
> > > > 
> > > > Cc: Michael S. Tsirkin <mst@redhat.com>
> > > > Cc: Paolo Bonzini <pbonzini@redhat.com>
> > > > Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> > > > Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> > > > Signed-off-by: Greg Kurz <groug@kaod.org>
> > > 
> > > Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> > 
> > I've applied this tentatively to ppc-for-4.0.  Let me know, Michael,
> > if you'd prefer to take it through your tree.
> 
> 
> I think your tree makes sense for this.

Great, will do.

> 
> > > 
> > > > ---
> > > >  hw/pci/pci.c         |   33 +++++++++++++++++++++++++++++++++
> > > >  include/hw/pci/pci.h |    3 +++
> > > >  2 files changed, 36 insertions(+)
> > > > 
> > > > diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> > > > index efb5ce196ffb..16354f91206c 100644
> > > > --- a/hw/pci/pci.c
> > > > +++ b/hw/pci/pci.c
> > > > @@ -333,6 +333,13 @@ static void pci_host_bus_register(DeviceState *host)
> > > >      QLIST_INSERT_HEAD(&pci_host_bridges, host_bridge, next);
> > > >  }
> > > >  
> > > > +static void pci_host_bus_unregister(DeviceState *host)
> > > > +{
> > > > +    PCIHostState *host_bridge = PCI_HOST_BRIDGE(host);
> > > > +
> > > > +    QLIST_REMOVE(host_bridge, next);
> > > > +}
> > > > +
> > > >  PCIBus *pci_device_root_bus(const PCIDevice *d)
> > > >  {
> > > >      PCIBus *bus = pci_get_bus(d);
> > > > @@ -379,6 +386,11 @@ static void pci_root_bus_init(PCIBus *bus, DeviceState *parent,
> > > >      pci_host_bus_register(parent);
> > > >  }
> > > >  
> > > > +static void pci_bus_uninit(PCIBus *bus)
> > > > +{
> > > > +    pci_host_bus_unregister(BUS(bus)->parent);
> > > > +}
> > > > +
> > > >  bool pci_bus_is_express(PCIBus *bus)
> > > >  {
> > > >      return object_dynamic_cast(OBJECT(bus), TYPE_PCIE_BUS);
> > > > @@ -413,6 +425,12 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
> > > >      return bus;
> > > >  }
> > > >  
> > > > +void pci_root_bus_cleanup(PCIBus *bus)
> > > > +{
> > > > +    pci_bus_uninit(bus);
> > > > +    object_unparent(OBJECT(bus));
> > > > +}
> > > > +
> > > >  void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> > > >                    void *irq_opaque, int nirq)
> > > >  {
> > > > @@ -423,6 +441,15 @@ 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_irqs_cleanup(PCIBus *bus)
> > > > +{
> > > > +    bus->set_irq = NULL;
> > > > +    bus->map_irq = NULL;
> > > > +    bus->irq_opaque = NULL;
> > > > +    bus->nirq = 0;
> > > > +    g_free(bus->irq_count);
> > > > +}
> > > > +
> > > >  PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
> > > >                                pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> > > >                                void *irq_opaque,
> > > > @@ -439,6 +466,12 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
> > > >      return bus;
> > > >  }
> > > >  
> > > > +void pci_unregister_root_bus(PCIBus *bus)
> > > > +{
> > > > +    pci_bus_irqs_cleanup(bus);
> > > > +    pci_root_bus_cleanup(bus);
> > > > +}
> > > > +
> > > >  int pci_bus_num(PCIBus *s)
> > > >  {
> > > >      return PCI_BUS_GET_CLASS(s)->bus_num(s);
> > > > diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> > > > index e6514bba23aa..8998e3be3390 100644
> > > > --- a/include/hw/pci/pci.h
> > > > +++ b/include/hw/pci/pci.h
> > > > @@ -405,8 +405,10 @@ PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
> > > >                           MemoryRegion *address_space_mem,
> > > >                           MemoryRegion *address_space_io,
> > > >                           uint8_t devfn_min, const char *typename);
> > > > +void pci_root_bus_cleanup(PCIBus *bus);
> > > >  void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
> > > >                    void *irq_opaque, int nirq);
> > > > +void pci_bus_irqs_cleanup(PCIBus *bus);
> > > >  int pci_bus_get_irq_level(PCIBus *bus, int irq_num);
> > > >  /* 0 <= pin <= 3 0 = INTA, 1 = INTB, 2 = INTC, 3 = INTD */
> > > >  int pci_swizzle_map_irq_fn(PCIDevice *pci_dev, int pin);
> > > > @@ -417,6 +419,7 @@ PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
> > > >                                MemoryRegion *address_space_io,
> > > >                                uint8_t devfn_min, int nirq,
> > > >                                const char *typename);
> > > > +void pci_unregister_root_bus(PCIBus *bus);
> > > >  void pci_bus_set_route_irq_fn(PCIBus *, pci_route_irq_fn);
> > > >  PCIINTxRoute pci_device_route_intx_to_irq(PCIDevice *dev, int pin);
> > > >  bool pci_intx_route_changed(PCIINTxRoute *old, PCIINTxRoute *new);
> > > 
> > 
> 
> 

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson