Will Deacon 6d1bcb957b iommu: Remove empty iommu_tlb_range_add() callback from iommu_ops ... Commit add02cfdc9 ("iommu: Introduce Interface for IOMMU TLB Flushing") added three new TLB flushing operations to the IOMMU API so that the underlying driver operations can be batched when unmapping large regions of IO virtual address space. However, the ->iotlb_range_add() callback has not been implemented by any IOMMU drivers (amd_iommu.c implements it as an empty function, which incurs the overhead of an indirect branch). Instead, drivers either flush the entire IOTLB in the ->iotlb_sync() callback or perform the necessary invalidation during ->unmap(). Attempting to implement ->iotlb_range_add() for arm-smmu-v3.c revealed two major issues: 1. The page size used to map the region in the page-table is not known, and so it is not generally possible to issue TLB flushes in the most efficient manner. 2. The only mutable state passed to the callback is a pointer to the iommu_domain, which can be accessed concurrently and therefore requires expensive synchronisation to keep track of the outstanding flushes. Remove the callback entirely in preparation for extending ->unmap() and ->iotlb_sync() to update a token on the caller's stack. Signed-off-by: Will Deacon <will@kernel.org>		2019-07-24 13:32:33 +01:00
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mdev	VFIO updates for v5.3-rc1	2019-07-17 11:23:13 -07:00
pci	vfio: vfio_pci_nvlink2: use a vma helper function	2019-07-02 11:44:12 -06:00
platform	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201	2019-05-30 11:29:52 -07:00
Kconfig	docs: driver-api: add a series of orphaned documents	2019-07-15 11:03:02 -03:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
vfio.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
vfio_iommu_spapr_tce.c	mm: add account_locked_vm utility function	2019-07-16 19:23:25 -07:00
vfio_iommu_type1.c	iommu: Remove empty iommu_tlb_range_add() callback from iommu_ops	2019-07-24 13:32:33 +01:00
vfio_spapr_eeh.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
virqfd.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00