Re: [Qemu-devel] [PATCH v10 03/26] x86-iommu: q35: generalize find_add_as()

[Paolo Bonzini]

On 04/07/2016 17:16, Michael S. Tsirkin wrote:
> On Tue, Jun 21, 2016 at 03:47:31PM +0800, Peter Xu wrote:
>> Remove VT-d calls in common q35 codes. Instead, we provide a general
>> find_add_as() for x86-iommu type.
>>
>> Signed-off-by: Peter Xu <address@hidden>
> 
> I think it would be cleaner in the device,
> not in the type. In theory you could then mix
> multiple different iommu types in the same machine.

Not sure what you mean.  Each IOMMU subclass can define its own
find_add_as implementation, what's wrong with that?

Paolo

> 
>> ---
>>  hw/i386/intel_iommu.c         | 17 +++++++++--------
>>  include/hw/i386/intel_iommu.h |  5 -----
>>  include/hw/i386/x86-iommu.h   |  3 +++
>>  3 files changed, 12 insertions(+), 13 deletions(-)
>>
>> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
>> index 1936c41..b487224 100644
>> --- a/hw/i386/intel_iommu.c
>> +++ b/hw/i386/intel_iommu.c
>> @@ -1900,8 +1900,10 @@ static Property vtd_properties[] = {
>>  };
>>  
>>  
>> -VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int devfn)
>> +static AddressSpace *vtd_find_add_as(X86IOMMUState *x86_iommu, PCIBus *bus,
>> +                                     int devfn)
>>  {
>> +    IntelIOMMUState *s = (IntelIOMMUState *)x86_iommu;
>>      uintptr_t key = (uintptr_t)bus;
>>      VTDBus *vtd_bus = g_hash_table_lookup(s->vtd_as_by_busptr, &key);
>>      VTDAddressSpace *vtd_dev_as;
>> @@ -1929,7 +1931,7 @@ VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, 
>> PCIBus *bus, int devfn)
>>          address_space_init(&vtd_dev_as->as,
>>                             &vtd_dev_as->iommu, "intel_iommu");
>>      }
>> -    return vtd_dev_as;
>> +    return &vtd_dev_as->as;
>>  }
>>  
>>  /* Do the initialization. It will also be called when reset, so pay
>> @@ -2021,13 +2023,11 @@ static void vtd_reset(DeviceState *dev)
>>  
>>  static AddressSpace *vtd_host_dma_iommu(PCIBus *bus, void *opaque, int 
>> devfn)
>>  {
>> -    IntelIOMMUState *s = opaque;
>> -    VTDAddressSpace *vtd_as;
>> -
>> -    assert(0 <= devfn && devfn <= VTD_PCI_DEVFN_MAX);
>> +    X86IOMMUState *x86_iommu = opaque;
>> +    X86IOMMUClass *x86_class = X86_IOMMU_GET_CLASS(x86_iommu);
>>  
>> -    vtd_as = vtd_find_add_as(s, bus, devfn);
>> -    return &vtd_as->as;
>> +    assert(0 <= devfn && devfn <= X86_IOMMU_PCI_DEVFN_MAX);
>> +    return x86_class->find_add_as(x86_iommu, bus, devfn);
>>  }
>>  
>>  static void vtd_realize(DeviceState *dev, Error **errp)
>> @@ -2060,6 +2060,7 @@ static void vtd_class_init(ObjectClass *klass, void 
>> *data)
>>      dc->vmsd = &vtd_vmstate;
>>      dc->props = vtd_properties;
>>      x86_class->realize = vtd_realize;
>> +    x86_class->find_add_as = vtd_find_add_as;
>>  }
>>  
>>  static const TypeInfo vtd_info = {
>> diff --git a/include/hw/i386/intel_iommu.h b/include/hw/i386/intel_iommu.h
>> index 0794309..e36b896 100644
>> --- a/include/hw/i386/intel_iommu.h
>> +++ b/include/hw/i386/intel_iommu.h
>> @@ -125,9 +125,4 @@ struct IntelIOMMUState {
>>      VTDBus *vtd_as_by_bus_num[VTD_PCI_BUS_MAX]; /* VTDBus objects indexed 
>> by bus number */
>>  };
>>  
>> -/* Find the VTD Address space associated with the given bus pointer,
>> - * create a new one if none exists
>> - */
>> -VTDAddressSpace *vtd_find_add_as(IntelIOMMUState *s, PCIBus *bus, int 
>> devfn);
>> -
>>  #endif
>> diff --git a/include/hw/i386/x86-iommu.h b/include/hw/i386/x86-iommu.h
>> index d6991cb..2070cd1 100644
>> --- a/include/hw/i386/x86-iommu.h
>> +++ b/include/hw/i386/x86-iommu.h
>> @@ -21,6 +21,7 @@
>>  #define IOMMU_COMMON_H
>>  
>>  #include "hw/sysbus.h"
>> +#include "exec/memory.h"
>>  
>>  #define  TYPE_X86_IOMMU_DEVICE  ("x86-iommu")
>>  #define  X86_IOMMU_DEVICE(obj) \
>> @@ -40,6 +41,8 @@ struct X86IOMMUClass {
>>      SysBusDeviceClass parent;
>>      /* Intel/AMD specific realize() hook */
>>      DeviceRealize realize;
>> +    /* Find/Add IOMMU address space for specific PCI device */
>> +    AddressSpace *(*find_add_as)(X86IOMMUState *s, PCIBus *bus, int devfn);
>>  };
>>  
>>  struct X86IOMMUState {
>> -- 
>> 2.4.11
> 
>