diff options
| author | Jason Gunthorpe <jgg@nvidia.com> | 2024-10-30 21:20:45 -0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2024-11-05 10:24:16 +0000 |
| commit | 35890f85573c2ebbbf3491dc66f7ee2ad63055af (patch) | |
| tree | f0cbe13de7e9d37af70aee59f0196df087713ed4 /include | |
| parent | 8e929cb546ee42c9a61d24fae60605e9e3192354 (diff) | |
vfio: Remove VFIO_TYPE1_NESTING_IOMMU
This control causes the ARM SMMU drivers to choose a stage 2
implementation for the IO pagetable (vs the stage 1 usual default),
however this choice has no significant visible impact to the VFIO
user. Further qemu never implemented this and no other userspace user is
known.
The original description in commit f5c9ecebaf2a ("vfio/iommu_type1: add
new VFIO_TYPE1_NESTING_IOMMU IOMMU type") suggested this was to "provide
SMMU translation services to the guest operating system" however the rest
of the API to set the guest table pointer for the stage 1 and manage
invalidation was never completed, or at least never upstreamed, rendering
this part useless dead code.
Upstream has now settled on iommufd as the uAPI for controlling nested
translation. Choosing the stage 2 implementation should be done by through
the IOMMU_HWPT_ALLOC_NEST_PARENT flag during domain allocation.
Remove VFIO_TYPE1_NESTING_IOMMU and everything under it including the
enable_nesting iommu_domain_op.
Just in-case there is some userspace using this continue to treat
requesting it as a NOP, but do not advertise support any more.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Mostafa Saleh <smostafa@google.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Donald Dutile <ddutile@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1-v4-9e99b76f3518+3a8-smmuv3_nesting_jgg@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/iommu.h | 3 | ||||
| -rw-r--r-- | include/uapi/linux/vfio.h | 2 |
2 files changed, 1 insertions, 4 deletions
diff --git a/include/linux/iommu.h b/include/linux/iommu.h index bd722f473635..c88d18d2c928 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -635,7 +635,6 @@ struct iommu_ops { * @enforce_cache_coherency: Prevent any kind of DMA from bypassing IOMMU_CACHE, * including no-snoop TLPs on PCIe or other platform * specific mechanisms. - * @enable_nesting: Enable nesting * @set_pgtable_quirks: Set io page table quirks (IO_PGTABLE_QUIRK_*) * @free: Release the domain after use. */ @@ -663,7 +662,6 @@ struct iommu_domain_ops { dma_addr_t iova); bool (*enforce_cache_coherency)(struct iommu_domain *domain); - int (*enable_nesting)(struct iommu_domain *domain); int (*set_pgtable_quirks)(struct iommu_domain *domain, unsigned long quirks); @@ -844,7 +842,6 @@ extern void iommu_group_put(struct iommu_group *group); extern int iommu_group_id(struct iommu_group *group); extern struct iommu_domain *iommu_group_default_domain(struct iommu_group *); -int iommu_enable_nesting(struct iommu_domain *domain); int iommu_set_pgtable_quirks(struct iommu_domain *domain, unsigned long quirks); diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 2b68e6cdf190..c8dbf8219c4f 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -35,7 +35,7 @@ #define VFIO_EEH 5 /* Two-stage IOMMU */ -#define VFIO_TYPE1_NESTING_IOMMU 6 /* Implies v2 */ +#define __VFIO_RESERVED_TYPE1_NESTING_IOMMU 6 /* Implies v2 */ #define VFIO_SPAPR_TCE_v2_IOMMU 7 |