On 2022/3/31 20:59, Jason Gunthorpe wrote:
On Wed, Mar 30, 2022 at 09:35:52PM +0800, Yi Liu wrote:
+/**
+ * struct iommu_ioas_copy - ioctl(IOMMU_IOAS_COPY)
+ * @size: sizeof(struct iommu_ioas_copy)
+ * @flags: Combination of enum iommufd_ioas_map_flags
+ * @dst_ioas_id: IOAS ID to change the mapping of
+ * @src_ioas_id: IOAS ID to copy from
so the dst and src ioas_id are allocated via the same iommufd.
right? just out of curious, do you think it is possible that
the srs/dst ioas_ids are from different iommufds? In that case
may need to add src/dst iommufd. It's not needed today, just to
see if any blocker in kernel to support such copy. :-)
Yes, all IDs in all ioctls are within the scope of a single iommufd.
There should be no reason for a single application to open multiple
iommufds.
then should this be documented?
--
Regards,
Yi Liu
