iommu: Add attach/detach_dev_pasid iommu interfaces
Attaching an IOMMU domain to a PASID of a device is a generic operation for modern IOMMU drivers which support PASID-granular DMA address translation. Currently visible usage scenarios include (but not limited): - SVA (Shared Virtual Address) - kernel DMA with PASID - hardware-assist mediated device This adds the set_dev_pasid domain ops for setting the domain onto a PASID of a device and remove_dev_pasid iommu ops for removing any setup on a PASID of device. This also adds interfaces for device drivers to attach/detach/retrieve a domain for a PASID of a device. If multiple devices share a single group, it's fine as long the fabric always routes every TLP marked with a PASID to the host bridge and only the host bridge. For example, ACS achieves this universally and has been checked when pci_enable_pasid() is called. As we can't reliably tell the source apart in a group, all the devices in a group have to be considered as the same source, and mapped to the same PASID table. The DMA ownership is about the whole device (more precisely, iommu group), including the RID and PASIDs. When the ownership is converted, the pasid array must be empty. This also adds necessary checks in the DMA ownership interfaces. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Yi Liu <yi.l.liu@intel.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org> Tested-by: Tony Zhu <tony.zhu@intel.com> Link: https://lore.kernel.org/r/20221031005917.45690-6-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
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