linux-stable.git/include/linux/iommu.h, branch v6.0.2

iommu: remove the put_resv_regions method

2022-07-15T08:13:45+00:00

All drivers that implement get_resv_regions just use
generic_put_resv_regions to implement the put side.  Remove the
indirections and document the allocations constraints.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Lu Baolu 
Link: https://lore.kernel.org/r/20220708080616.238833-4-hch@lst.de
Signed-off-by: Joerg Roedel

iommu: remove iommu_dev_feature_enabled

2022-07-15T08:13:45+00:00

Remove the unused iommu_dev_feature_enabled function.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Lu Baolu 
Link: https://lore.kernel.org/r/20220708080616.238833-3-hch@lst.de
Signed-off-by: Joerg Roedel

iommu: remove the unused dev_has_feat method

2022-07-15T08:13:44+00:00

This method is never actually called.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Lu Baolu 
Link: https://lore.kernel.org/r/20220708080616.238833-2-hch@lst.de
Signed-off-by: Joerg Roedel

ACPI/IORT: Add support to retrieve IORT RMR reserved regions

2022-07-06T10:51:10+00:00

Parse through the IORT RMR nodes and populate the reserve region list
corresponding to a given IOMMU and device(optional). Also, go through
the ID mappings of the RMR node and retrieve all the SIDs associated
with it.

Reviewed-by: Lorenzo Pieralisi 
Tested-by: Steven Price 
Tested-by: Laurentiu Tudor 
Tested-by: Hanjun Guo 
Reviewed-by: Hanjun Guo 
Signed-off-by: Shameer Kolothum 
Acked-by: Robin Murphy 
Link: https://lore.kernel.org/r/20220615101044.1972-5-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Joerg Roedel

iommu: Introduce a callback to struct iommu_resv_region

2022-07-06T10:51:10+00:00

A callback is introduced to struct iommu_resv_region to free memory
allocations associated with the reserved region. This will be useful
when we introduce support for IORT RMR based reserved regions.

Reviewed-by: Christoph Hellwig 
Tested-by: Steven Price 
Tested-by: Laurentiu Tudor 
Tested-by: Hanjun Guo 
Signed-off-by: Shameer Kolothum 
Acked-by: Robin Murphy 
Link: https://lore.kernel.org/r/20220615101044.1972-2-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Joerg Roedel

Merge branches 'apple/dart', 'arm/mediatek', 'arm/msm', 'arm/smmu', 'ppc/pamu', 'x86/vt-d', 'x86/amd' and 'vfio-notifier-fix' into next

2022-05-20T10:27:17+00:00

iommu: Redefine IOMMU_CAP_CACHE_COHERENCY as the cap flag for IOMMU_CACHE

2022-04-28T15:24:57+00:00

While the comment was correct that this flag was intended to convey the
block no-snoop support in the IOMMU, it has become widely implemented and
used to mean the IOMMU supports IOMMU_CACHE as a map flag. Only the Intel
driver was different.

Now that the Intel driver is using enforce_cache_coherency() update the
comment to make it clear that IOMMU_CAP_CACHE_COHERENCY is only about
IOMMU_CACHE.  Fix the Intel driver to return true since IOMMU_CACHE always
works.

The two places that test this flag, usnic and vdpa, are both assigning
userspace pages to a driver controlled iommu_domain and require
IOMMU_CACHE behavior as they offer no way for userspace to synchronize
caches.

Reviewed-by: Kevin Tian 
Reviewed-by: Lu Baolu 
Acked-by: Robin Murphy 
Signed-off-by: Jason Gunthorpe 
Link: https://lore.kernel.org/r/3-v3-2cf356649677+a32-intel_no_snoop_jgg@nvidia.com
Signed-off-by: Joerg Roedel

iommu: Introduce the domain op enforce_cache_coherency()

2022-04-28T15:24:57+00:00

This new mechanism will replace using IOMMU_CAP_CACHE_COHERENCY and
IOMMU_CACHE to control the no-snoop blocking behavior of the IOMMU.

Currently only Intel and AMD IOMMUs are known to support this
feature. They both implement it as an IOPTE bit, that when set, will cause
PCIe TLPs to that IOVA with the no-snoop bit set to be treated as though
the no-snoop bit was clear.

The new API is triggered by calling enforce_cache_coherency() before
mapping any IOVA to the domain which globally switches on no-snoop
blocking. This allows other implementations that might block no-snoop
globally and outside the IOPTE - AMD also documents such a HW capability.

Leave AMD out of sync with Intel and have it block no-snoop even for
in-kernel users. This can be trivially resolved in a follow up patch.

Only VFIO needs to call this API because it does not have detailed control
over the device to avoid requesting no-snoop behavior at the device
level. Other places using domains with real kernel drivers should simply
avoid asking their devices to set the no-snoop bit.

Reviewed-by: Lu Baolu 
Reviewed-by: Kevin Tian 
Acked-by: Robin Murphy 
Signed-off-by: Jason Gunthorpe 
Link: https://lore.kernel.org/r/1-v3-2cf356649677+a32-intel_no_snoop_jgg@nvidia.com
Signed-off-by: Joerg Roedel

iommu: Remove iommu group changes notifier

2022-04-28T13:32:20+00:00

The iommu group changes notifer is not referenced in the tree. Remove it
to avoid dead code.

Suggested-by: Christoph Hellwig 
Signed-off-by: Lu Baolu 
Reviewed-by: Jason Gunthorpe 
Link: https://lore.kernel.org/r/20220418005000.897664-12-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel

iommu: Add DMA ownership management interfaces

2022-04-28T13:32:20+00:00

Multiple devices may be placed in the same IOMMU group because they
cannot be isolated from each other. These devices must either be
entirely under kernel control or userspace control, never a mixture.

This adds dma ownership management in iommu core and exposes several
interfaces for the device drivers and the device userspace assignment
framework (i.e. VFIO), so that any conflict between user and kernel
controlled dma could be detected at the beginning.

The device driver oriented interfaces are,

	int iommu_device_use_default_domain(struct device *dev);
	void iommu_device_unuse_default_domain(struct device *dev);

By calling iommu_device_use_default_domain(), the device driver tells
the iommu layer that the device dma is handled through the kernel DMA
APIs. The iommu layer will manage the IOVA and use the default domain
for DMA address translation.

The device user-space assignment framework oriented interfaces are,

	int iommu_group_claim_dma_owner(struct iommu_group *group,
					void *owner);
	void iommu_group_release_dma_owner(struct iommu_group *group);
	bool iommu_group_dma_owner_claimed(struct iommu_group *group);

The device userspace assignment must be disallowed if the DMA owner
claiming interface returns failure.

Signed-off-by: Jason Gunthorpe 
Signed-off-by: Kevin Tian 
Signed-off-by: Lu Baolu 
Reviewed-by: Robin Murphy 
Link: https://lore.kernel.org/r/20220418005000.897664-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel