Hi Cédric,
>-----Original Message-----
>From: Cédric Le Goater <c...@redhat.com>
>Sent: Friday, November 10, 2023 5:36 PM
>Subject: Re: [PATCH v5 05/20] vfio/iommufd: Add support for iova_ranges and
>pgsizes
>
>On 11/9/23 12:45, 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.
>>
>> Also use out_iova_alignment returned from uAPI as pgsizes instead of
>> qemu_real_host_page_size() as a fallback.
>>
>> Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
>> ---
>> v5: Add missed pgsizes initialization in vfio_get_info_iova_range
>>
>> hw/vfio/iommufd.c | 48
>+++++++++++++++++++++++++++++++++++++++++++++++
>> 1 file changed, 48 insertions(+)
>>
>> diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
>> index ea4e23f4ec..958c3e794f 100644
>> --- a/hw/vfio/iommufd.c
>> +++ b/hw/vfio/iommufd.c
>> @@ -267,6 +267,53 @@ 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 *)(uintptr_t)info->allowed_iovas;
>> +
>> + for (int i = 0; i < info->num_iovas; i++) {
>> + Range *range = g_new(Range, 1);
>> +
>> + range_set_bounds(range, iova_ranges[i].start, iova_ranges[i].last);
>> + bcontainer->iova_ranges =
>> + range_list_insert(bcontainer->iova_ranges, range);
>> + }
>> + bcontainer->pgsizes = info->out_iova_alignment;
>> +
>> + g_free(info);
>> + return 0;
>> +
>> +error:
>> + ret = -errno;
>> + g_free(info);
>> + error_report("vfio/iommufd: Cannot get iova ranges: %m");
>
>Can we propagate the error ?
Do you mean propagating the error to call site and call error_report?
In fact, getting iova range from host is a better to have, not a must.
If fails we fallback to 64bit range.
Thanks
Zhenzhong
