mbox series

[0/5] Simplify vfio_iommu_type1 attach/detach routine

Message ID 20220606061927.26049-1-nicolinc@nvidia.com
Headers show
Series Simplify vfio_iommu_type1 attach/detach routine | expand

Message

Nicolin Chen June 6, 2022, 6:19 a.m. UTC
This is a preparatory series for IOMMUFD v2 patches. It enforces error
code -EMEDIUMTYPE in iommu_attach_device() and iommu_attach_group() when
an IOMMU domain and a device/group are incompatible. It also moves the
domain->ops check into __iommu_attach_device(). These allow VFIO iommu
code to simplify its group attachment routine, by avoiding the extra
IOMMU domain allocations and attach/detach sequences of the old code.

Worths mentioning the exact match for enforce_cache_coherency is removed
with this series, since there's very less value in doing that since KVM
won't be able to take advantage of it -- this just wastes domain memory.
Instead, we rely on Intel IOMMU driver taking care of that internally.

This is on github: https://github.com/nicolinc/iommufd/commits/vfio_iommu_attach

Jason Gunthorpe (1):
  vfio/iommu_type1: Prefer to reuse domains vs match enforced cache
    coherency

Nicolin Chen (4):
  iommu: Return -EMEDIUMTYPE for incompatible domain and device/group
  iommu: Ensure device has the same iommu_ops as the domain
  vfio/iommu_type1: Clean up update_dirty_scope in detach_group()
  vfio/iommu_type1: Simplify group attachment

 drivers/iommu/amd/iommu.c                   |   3 +-
 drivers/iommu/apple-dart.c                  |   5 +-
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c |   7 +-
 drivers/iommu/arm/arm-smmu/arm-smmu.c       |   1 +
 drivers/iommu/arm/arm-smmu/qcom_iommu.c     |   3 +-
 drivers/iommu/exynos-iommu.c                |   1 +
 drivers/iommu/fsl_pamu_domain.c             |   1 +
 drivers/iommu/intel/iommu.c                 |   5 +-
 drivers/iommu/iommu.c                       |  26 ++
 drivers/iommu/ipmmu-vmsa.c                  |   3 +-
 drivers/iommu/msm_iommu.c                   |   1 +
 drivers/iommu/mtk_iommu.c                   |   1 +
 drivers/iommu/mtk_iommu_v1.c                |   1 +
 drivers/iommu/omap-iommu.c                  |   3 +-
 drivers/iommu/rockchip-iommu.c              |   1 +
 drivers/iommu/s390-iommu.c                  |   1 +
 drivers/iommu/sprd-iommu.c                  |   1 +
 drivers/iommu/sun50i-iommu.c                |   1 +
 drivers/iommu/tegra-gart.c                  |   1 +
 drivers/iommu/tegra-smmu.c                  |   1 +
 drivers/iommu/virtio-iommu.c                |   3 +-
 drivers/vfio/vfio_iommu_type1.c             | 315 ++++++++++----------
 include/linux/iommu.h                       |   2 +
 23 files changed, 223 insertions(+), 164 deletions(-)

Comments

Baolu Lu June 7, 2022, 12:42 p.m. UTC | #1
On 2022/6/7 19:58, Jason Gunthorpe wrote:
> On Tue, Jun 07, 2022 at 03:44:43PM +0800, Baolu Lu wrote:
>> On 2022/6/6 14:19, Nicolin Chen wrote:
>>> Worths mentioning the exact match for enforce_cache_coherency is removed
>>> with this series, since there's very less value in doing that since KVM
>>> won't be able to take advantage of it -- this just wastes domain memory.
>>> Instead, we rely on Intel IOMMU driver taking care of that internally.
>>
>> After reading this series, I don't see that Intel IOMMU driver needs any
>> further change to support the new scheme. Did I miss anything?
> 
> You already did it :)

Just as I thought. Thank you!

Best regards,
baolu