On 2022/5/17 下午4:55, Yi Liu wrote:
Hi Zhangfei,
On 2022/5/12 17:01, zhangfei.gao@xxxxxxxxxxx wrote:
Hi, Yi
On 2022/5/11 下午10:17, zhangfei.gao@xxxxxxxxxxx wrote:
On 2022/5/10 下午10:08, Yi Liu wrote:
On 2022/5/10 20:45, Jason Gunthorpe wrote:
On Tue, May 10, 2022 at 08:35:00PM +0800, Zhangfei Gao wrote:
Thanks Yi and Eric,
Then will wait for the updated iommufd kernel for the PCI MMIO
region.
Another question,
How to get the iommu_domain in the ioctl.
The ID of the iommu_domain (called the hwpt) it should be returned by
the vfio attach ioctl.
yes, hwpt_id is returned by the vfio attach ioctl and recorded in
qemu. You can query page table related capabilities with this id.
https://lore.kernel.org/kvm/20220414104710.28534-16-yi.l.liu@xxxxxxxxx/
Thanks Yi,
Do we use iommufd_hw_pagetable_from_id in kernel?
The qemu send hwpt_id via ioctl.
Currently VFIOIOMMUFDContainer has hwpt_list,
Which member is good to save hwpt_id, IOMMUTLBEntry?
Can VFIOIOMMUFDContainer have multi hwpt?
yes, it is possible
Then how to get hwpt_id in map/unmap_notify(IOMMUNotifier *n,
IOMMUTLBEntry *iotlb)
Since VFIOIOMMUFDContainer has hwpt_list now.
If so, how to get specific hwpt from map/unmap_notify in
hw/vfio/as.c, where no vbasedev can be used for compare.
I am testing with a workaround, adding VFIOIOASHwpt *hwpt in
VFIOIOMMUFDContainer.
And save hwpt when vfio_device_attach_container.
In kernel ioctl: iommufd_vfio_ioctl
@dev: Device to get an iommu_domain for
iommufd_hw_pagetable_from_id(struct iommufd_ctx *ictx, u32 pt_id,
struct device *dev)
But iommufd_vfio_ioctl seems no para dev?
We can set dev=Null since IOMMUFD_OBJ_HW_PAGETABLE does not need dev.
iommufd_hw_pagetable_from_id(ictx, hwpt_id, NULL)
this is not good. dev is passed in to this function to allocate domain
and also check sw_msi things. If you pass in a NULL, it may even unable
to get a domain for the hwpt. It won't work I guess.
The iommufd_hw_pagetable_from_id can be used for
1, allocate domain, which need para dev
case IOMMUFD_OBJ_IOAS
hwpt = iommufd_hw_pagetable_auto_get(ictx, ioas, dev);
2. Just return allocated domain via hwpt_id, which does not need dev.
case IOMMUFD_OBJ_HW_PAGETABLE:
return container_of(obj, struct iommufd_hw_pagetable, obj);
By the way, any plan of the nested mode?
Thanks
