>-----Original Message-----
>From: Eric Auger <eric.au...@redhat.com>
>Subject: Re: [PATCH rfcv1 3/6] intel_iommu: add set/unset_iommu_device
>callback
>
>
>
>On 1/18/24 09:43, Duan, Zhenzhong wrote:
>>
>>> -----Original Message-----
>>> From: Eric Auger <eric.au...@redhat.com>
>>> Subject: Re: [PATCH rfcv1 3/6] intel_iommu: add
>set/unset_iommu_device
>>> callback
>>>
>>> Hi Zhenzhong,
>>>
>>> On 1/15/24 11:13, Zhenzhong Duan wrote:
>>>> From: Yi Liu <yi.l....@intel.com>
>>>>
>>>> This adds set/unset_iommu_device() implementation in Intel vIOMMU.
>>>> In set call, IOMMUFDDevice is recorded in hash table indexed by
>>>> PCI BDF.
>>>>
>>>> Signed-off-by: Yi Liu <yi.l....@intel.com>
>>>> Signed-off-by: Yi Sun <yi.y....@linux.intel.com>
>>>> Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
>>>> ---
>>>> include/hw/i386/intel_iommu.h | 10 +++++
>>>> hw/i386/intel_iommu.c | 79
>>> +++++++++++++++++++++++++++++++++++
>>>> 2 files changed, 89 insertions(+)
>>>>
>>>> diff --git a/include/hw/i386/intel_iommu.h
>>> b/include/hw/i386/intel_iommu.h
>>>> index 7fa0a695c8..c65fdde56f 100644
>>>> --- a/include/hw/i386/intel_iommu.h
>>>> +++ b/include/hw/i386/intel_iommu.h
>>>> @@ -62,6 +62,7 @@ typedef union VTD_IR_TableEntry
>VTD_IR_TableEntry;
>>>> typedef union VTD_IR_MSIAddress VTD_IR_MSIAddress;
>>>> typedef struct VTDPASIDDirEntry VTDPASIDDirEntry;
>>>> typedef struct VTDPASIDEntry VTDPASIDEntry;
>>>> +typedef struct VTDIOMMUFDDevice VTDIOMMUFDDevice;
>>>>
>>>> /* Context-Entry */
>>>> struct VTDContextEntry {
>>>> @@ -148,6 +149,13 @@ struct VTDAddressSpace {
>>>> IOVATree *iova_tree;
>>>> };
>>>>
>>>> +struct VTDIOMMUFDDevice {
>>>> + PCIBus *bus;
>>>> + uint8_t devfn;
>>>> + IOMMUFDDevice *idev;
>>>> + IntelIOMMUState *iommu_state;
>>>> +};
>>>> +
>>> Just wondering whether we shouldn't reuse the VTDAddressSpace to
>store
>>> the idev, if any. How have you made your choice. What will it become
>>> when PASID gets added?
>> VTDAddressSpace is indexed by aliased BDF, but VTDIOMMUFDDevice is
>indexed
>> by device's BDF. So we can't just store VTDIOMMUFDDevice as a pointer in
>> VTDAddressSpace, may need a list in case more than one device in same
>address
>> space. Then a global VTDIOMMUFDDevice list is better for lookup.
>
>OK but if several devices are hidden under an aliased BDF, can't they
>share the host properties (DMAR ecap/cap)?
It depends on that if the vfio devices are under same aliased BDF in host.
If vfio devices are configured under same aliased BDF in qemu but they are
not in same aliased BDF in host, their host cap/ecap may be different.
Thanks
Zhenzhong
