[PATCH v2 0/6] Replace private domain with per-group default domain

[Lu Baolu]

Some devices are reqired to use a specific type (identity or dma)
of default domain when they are used with a vendor iommu. When the
system level default domain type is different from it, the vendor
iommu driver has to request a new default domain with either
iommu_request_dma_domain_for_dev() or iommu_request_dm_for_dev()
in the add_dev() callback. Unfortunately, these two helpers only
work when the group hasn't been assigned to any other devices,
hence, some vendor iommu driver has to use a private domain if
it fails to request a new default one.

This patch series aims to remove the private domain requirement
in vendor iommu driver with enabling the iommu generic code to
support configuring per-group default domain. It introduces a
new callback in iommu_ops, named def_domain_type(), so that
the iommu generic code could check whether a device is required
to use any specific type of default domain during the process of
device probing.

If unlikely a device requires a special default domain type other
than that in use, iommu probe procedure will either allocate a new
domain according to the specified domain type, or (if the group has
other devices sitting in it) change the default domain. The vendor
iommu driver which exposes the def_domain_type callback should
guarantee that there're no multiple devices belonging to a same
group require differnt types of default domain.

Please help to review.

Best regards,
baolu

Change log:
v1->v2:
 - Rename the iommu ops callback to def_domain_type

Lu Baolu (5):
  iommu: Configure default domain with def_domain_type
  iommu/vt-d: Don't force 32bit devices to uses DMA domain
  iommu/vt-d: Don't force PCI sub-hierarchy to use DMA domain
  iommu/vt-d: Add def_domain_type callback
  iommu/vt-d: Apply per-device dma_ops

Sai Praneeth Prakhya (1):
  iommu: Add def_domain_type() callback in iommu_ops

 drivers/iommu/intel-iommu.c | 453 +++---------------------------------
 drivers/iommu/iommu.c       |  93 +++++++-
 include/linux/iommu.h       |   6 +
 3 files changed, 126 insertions(+), 426 deletions(-)

-- 
2.17.1