RE: [PATCH v4 30/41] vfio/iommufd: Add support for iova_ranges

[Duan, Zhenzhong]

>-----Original Message-----
>From: Cédric Le Goater <clg@redhat.com>
>Sent: Tuesday, November 7, 2023 1:19 AM
>Subject: Re: [PATCH v4 30/41] vfio/iommufd: Add support for iova_ranges
>
>On 11/2/23 08:12, Zhenzhong Duan wrote:
>> Some vIOMMU such as virtio-iommu use iova ranges from host side to
>> setup reserved ranges for passthrough device, so that guest will not
>> use an iova range beyond host support.
>>
>> Use an uAPI of IOMMUFD to get iova ranges of host side and pass to
>> vIOMMU just like the legacy backend.
>>
>> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
>> ---
>> v4: fix build error in 32bit fedora
>>
>>   hw/vfio/iommufd.c | 47
>+++++++++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 47 insertions(+)
>>
>> diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
>> index 1bb55ca2c4..22f02f92a9 100644
>> --- a/hw/vfio/iommufd.c
>> +++ b/hw/vfio/iommufd.c
>> @@ -341,6 +341,52 @@ static int iommufd_ram_block_discard_disable(bool
>state)
>>       return ram_block_uncoordinated_discard_disable(state);
>>   }
>>
>> +static int vfio_get_info_iova_range(VFIOIOMMUFDContainer *container,
>> +                                    uint32_t ioas_id)
>> +{
>> +    VFIOContainerBase *bcontainer = &container->bcontainer;
>> +    struct iommu_ioas_iova_ranges *info;
>> +    struct iommu_iova_range *iova_ranges;
>> +    int ret, sz, fd = container->be->fd;
>> +
>> +    info = g_malloc0(sizeof(*info));
>> +    info->size = sizeof(*info);
>> +    info->ioas_id = ioas_id;
>> +
>> +    ret = ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info);
>> +    if (ret && errno != EMSGSIZE) {
>> +        goto error;
>> +    }
>> +
>> +    sz = info->num_iovas * sizeof(struct iommu_iova_range);
>> +    info = g_realloc(info, sizeof(*info) + sz);
>> +    info->allowed_iovas = (uintptr_t)(info + 1);
>> +
>> +    ret = ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info);
>> +    if (ret) {
>> +        goto error;
>> +    }
>> +
>> +    iova_ranges = (struct iommu_iova_range *)info->allowed_iovas;
>
>iova_ranges = (struct iommu_iova_range *)(uintptr_t)info->allowed_iovas;

Will fix, thanks for point out.

BRs.
Zhenzhong