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* [RFC PATCH v2 0/6] powerpc: pSeries: vfio: iommu: Re-enable support for SPAPR TCE VFIO
@ 2024-04-30 20:05 Shivaprasad G Bhat
  2024-04-30 20:05 ` [RFC PATCH v2 1/6] powerpc/iommu: Move pSeries specific functions to pseries/iommu.c Shivaprasad G Bhat
                   ` (6 more replies)
  0 siblings, 7 replies; 13+ messages in thread
From: Shivaprasad G Bhat @ 2024-04-30 20:05 UTC (permalink / raw)
  To: mpe, tpearson, alex.williamson, linuxppc-dev, aik
  Cc: svaidy, robh, jroedel, sbhat, gbatra, jgg, aik, linux-kernel,
	mahesh, aneesh.kumar, brking, oohall, npiggin, kvm, ruscur,
	naveen.n.rao, vaibhav, msuchanek, joel

RFC v1 was posted here [1]. As I was testing more and fixing the
issues, I realized its clean to have the table_group_ops implemented
the way it is done on PowerNV and stop 'borrowing' the DMA windows
for pSeries.

This patch-set implements the iommu table_group_ops for pSeries for
VFIO SPAPR TCE sub-driver thereby enabling the VFIO support on POWER
pSeries machines.

So, this patchset is a re-write and not close to the V1 except
for few changes.

Structure of the patchset:
-------------------------
The first and fifth patches just code movements.

Second patch takes care of collecting the TCE and DDW information
for the vfio_iommu_spapr_tce_ddw_info during probe.

Third patch fixes the convention of using table[1] for VFs on
pSeries when used by the host driver.

Fourth patch fixes the VFIO to call TCE clear before unset window.

The last patch has the API implementations, please find the
details on its commit description.

Testing:
-------
Tested with nested guest for NVME card, Mellanox multi-function
card by attaching them to nested kvm guest running on a pSeries
lpar.
Also vfio-test [2] by Alex Willamson, was forked and updated to
add support for pSeries guest and used to test these patches[3].

Limitations/Known Issues:
------------------------
* The DMA window restrictions with SRIOV VF scenarios of having
maximum 1 dma window is taken care in the current patches itself.
However, the necessary changes required in
vfio_iommu_spapr_tce_ddw_info to expose the default window being
a 64-bit one and the qemu changes handle the same will be taken
care in next versions.
* KVM guest boot throws warning at remap_pfn_range_notrack(), on
the host, I will post the fix along in the next versions.
* The DLPAR hotplugged device has no FDT entry until next reboot,
default dma window property has to be preserved differently for
this case.

References:
----------
[1] https://lore.kernel.org/linuxppc-dev/171026724548.8367.8321359354119254395.stgit@linux.ibm.com/
[2] https://github.com/awilliam/tests
[3] https://github.com/nnmwebmin/vfio-ppc-tests/tree/vfio-ppc-ex

---
Changelog:
v1: https://lore.kernel.org/linuxppc-dev/171026724548.8367.8321359354119254395.stgit@linux.ibm.com/
 - Rewrite as to stop borrowing the DMA windows and implemented
 the table_group_ops for pSeries.
 - Cover letter and Patch 6 has more details as this was a rewrite.

Shivaprasad G Bhat (6):
      powerpc/iommu: Move pSeries specific functions to pseries/iommu.c
      powerpc/pseries/iommu: Fix the VFIO_IOMMU_SPAPR_TCE_GET_INFO ioctl output
      powerpc/pseries/iommu: Use the iommu table[0] for IOV VF's DDW
      vfio/spapr: Always clear TCEs before unsetting the window
      powerpc/iommu: Move dev_has_iommu_table() to iommu.c
      powerpc/iommu: Implement the iommu_table_group_ops for pSeries


 arch/powerpc/include/asm/iommu.h          |   9 +-
 arch/powerpc/kernel/eeh.c                 |  16 -
 arch/powerpc/kernel/iommu.c               | 170 +----
 arch/powerpc/platforms/powernv/pci-ioda.c |   6 +-
 arch/powerpc/platforms/pseries/iommu.c    | 720 +++++++++++++++++++++-
 drivers/vfio/vfio_iommu_spapr_tce.c       |  13 +-
 6 files changed, 729 insertions(+), 205 deletions(-)

--
Signature


^ permalink raw reply	[flat|nested] 13+ messages in thread

end of thread, other threads:[~2024-05-10 18:43 UTC | newest]

Thread overview: 13+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-04-30 20:05 [RFC PATCH v2 0/6] powerpc: pSeries: vfio: iommu: Re-enable support for SPAPR TCE VFIO Shivaprasad G Bhat
2024-04-30 20:05 ` [RFC PATCH v2 1/6] powerpc/iommu: Move pSeries specific functions to pseries/iommu.c Shivaprasad G Bhat
2024-04-30 20:06 ` [RFC PATCH v2 2/6] powerpc/pseries/iommu: Fix the VFIO_IOMMU_SPAPR_TCE_GET_INFO ioctl output Shivaprasad G Bhat
2024-04-30 20:06 ` [RFC PATCH v2 3/6] powerpc/pseries/iommu: Use the iommu table[0] for IOV VF's DDW Shivaprasad G Bhat
2024-04-30 20:06 ` [RFC PATCH v2 4/6] vfio/spapr: Always clear TCEs before unsetting the window Shivaprasad G Bhat
2024-04-30 20:06 ` [RFC PATCH v2 5/6] powerpc/iommu: Move dev_has_iommu_table() to iommu.c Shivaprasad G Bhat
2024-04-30 20:06 ` [RFC PATCH v2 6/6] powerpc/iommu: Implement the iommu_table_group_ops for pSeries Shivaprasad G Bhat
2024-05-01 14:09 ` [RFC PATCH v2 0/6] powerpc: pSeries: vfio: iommu: Re-enable support for SPAPR TCE VFIO Jason Gunthorpe
2024-05-02  1:29   ` Alexey Kardashevskiy
2024-05-03 19:03     ` Shivaprasad G Bhat
2024-05-06 17:43       ` Jason Gunthorpe
2024-05-07 15:10         ` Shivaprasad G Bhat
2024-05-10 18:33         ` Shawn Anastasio

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