>-----Original Message-----
>From: Cédric Le Goater <c...@redhat.com>
>Sent: Tuesday, November 14, 2023 9:46 PM
>Subject: Re: [PATCH v6 06/21] vfio/iommufd: Add support for iova_ranges and
>pgsizes
>
>On 11/14/23 11:09, 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, if this fails, fallback to
>> 64bit IOVA range.
>>
>> 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>
>> ---
>> v6: propagate iommufd_cdev_get_info_iova_range err and print as warning
>>
>> hw/vfio/iommufd.c | 55
>++++++++++++++++++++++++++++++++++++++++++++++-
>> 1 file changed, 54 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
>> index 06282d885c..e5bf528e89 100644
>> --- a/hw/vfio/iommufd.c
>> +++ b/hw/vfio/iommufd.c
>> @@ -267,6 +267,53 @@ static int
>iommufd_cdev_ram_block_discard_disable(bool state)
>> return ram_block_uncoordinated_discard_disable(state);
>> }
>>
>> +static int iommufd_cdev_get_info_iova_range(VFIOIOMMUFDContainer
>*container,
>> + uint32_t ioas_id, Error **errp)
>> +{
>> + 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_setg_errno(errp, errno, "Cannot get IOVA ranges");
>> + return ret;
>> +}
>> +
>> static int iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
>> AddressSpace *as, Error **errp)
>> {
>> @@ -341,7 +388,13 @@ static int iommufd_cdev_attach(const char *name,
>VFIODevice *vbasedev,
>> goto err_discard_disable;
>> }
>>
>> - bcontainer->pgsizes = qemu_real_host_page_size();
>> + ret = iommufd_cdev_get_info_iova_range(container, ioas_id, &err);
>> + if (ret) {
>> + warn_report_err(err);
>> + err = NULL;
>> + error_printf("Fallback to default 64bit IOVA range and 4K page
>> size\n");
>
>This would be better :
>
> error_append_hint(&err,
> "Fallback to default 64bit IOVA range and 4K page size\n");
> warn_report_err(err);
>
>I will take care of it if you agree. With that,
Sure, thanks
BRs
Zhenzhong
>
>Reviewed-by: Cédric Le Goater <c...@redhat.com>
>
>Thanks,
>
>C.
>
>
>> + bcontainer->pgsizes = qemu_real_host_page_size();
>> + }
>>
>> bcontainer->listener = vfio_memory_listener;
>> memory_listener_register(&bcontainer->listener, bcontainer->space->as);
