[PATCH 0/9] iommu: Refactor flush queues into iommu-dma

From: Robin Murphy
Date: Tue Nov 23 2021 - 09:10:54 EST


Hi all,

As promised, this series cleans up the flush queue code and streamlines
it directly into iommu-dma. Since we no longer have per-driver DMA ops
implementations, a lot of the abstraction is now no longer necessary, so
there's a nice degree of simplification in the process. Un-abstracting
the queued page freeing mechanism is also the perfect opportunity to
revise which struct page fields we use so we can be better-behaved
from the MM point of view, thanks to Matthew.

These changes should also make it viable to start using the gather
freelist in io-pgtable-arm, and eliminate some more synchronous
invalidations from the normal flow there, but that is proving to need a
bit more careful thought than I have time for in this cycle, so I've
parked that again for now and will revisit it in the new year.

For convenience, branch at:
https://gitlab.arm.com/linux-arm/linux-rm/-/tree/iommu/iova

I've build-tested for x86_64, and boot-tested arm64 to the point of
confirming that put_pages_list() gets passed a valid empty list when
flushing, while everything else still works.

Cheers,
Robin.


Matthew Wilcox (Oracle) (2):
iommu/amd: Use put_pages_list
iommu/vt-d: Use put_pages_list

Robin Murphy (7):
gpu: host1x: Add missing DMA API include
iommu/iova: Squash entry_dtor abstraction
iommu/iova: Squash flush_cb abstraction
iommu/amd: Simplify pagetable freeing
iommu/iova: Consolidate flush queue code
iommu/iova: Move flush queue code to iommu-dma
iommu: Move flush queue data into iommu_dma_cookie

drivers/gpu/host1x/bus.c | 1 +
drivers/iommu/amd/io_pgtable.c | 116 ++++++--------
drivers/iommu/dma-iommu.c | 266 +++++++++++++++++++++++++++------
drivers/iommu/intel/iommu.c | 89 ++++-------
drivers/iommu/iova.c | 200 -------------------------
include/linux/iommu.h | 3 +-
include/linux/iova.h | 69 +--------
7 files changed, 295 insertions(+), 449 deletions(-)

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2.28.0.dirty