Pull iommu updates from Joerg Roedel:
"A big part of this is a change in how devices get connected to IOMMUs
in the core code. It contains the change from the old add_device() /
remove_device() to the new probe_device() / release_device()
call-backs.
As a result functionality that was previously in the IOMMU drivers has
been moved to the IOMMU core code, including IOMMU group allocation
for each device. The reason for this change was to get more robust
allocation of default domains for the iommu groups.
A couple of fixes were necessary after this was merged into the IOMMU
tree, but there are no known bugs left. The last fix is applied on-top
of the merge commit for the topic branches.
Other than that change, we have:
- Removal of the driver private domain handling in the Intel VT-d
driver. This was fragile code and I am glad it is gone now.
- More Intel VT-d updates from Lu Baolu:
- Nested Shared Virtual Addressing (SVA) support to the Intel VT-d
driver
- Replacement of the Intel SVM interfaces to the common IOMMU SVA
API
- SVA Page Request draining support
- ARM-SMMU Updates from Will:
- Avoid mapping reserved MMIO space on SMMUv3, so that it can be
claimed by the PMU driver
- Use xarray to manage ASIDs on SMMUv3
- Reword confusing shutdown message
- DT compatible string updates
- Allow implementations to override the default domain type
- A new IOMMU driver for the Allwinner Sun50i platform
- Support for ATS gets disabled for untrusted devices (like
Thunderbolt devices). This includes a PCI patch, acked by Bjorn.
- Some cleanups to the AMD IOMMU driver to make more use of IOMMU
core features.
- Unification of some printk formats in the Intel and AMD IOMMU
drivers and in the IOVA code.
- Updates for DT bindings
- A number of smaller fixes and cleanups.
* tag 'iommu-updates-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (109 commits)
iommu: Check for deferred attach in iommu_group_do_dma_attach()
iommu/amd: Remove redundant devid checks
iommu/amd: Store dev_data as device iommu private data
iommu/amd: Merge private header files
iommu/amd: Remove PD_DMA_OPS_MASK
iommu/amd: Consolidate domain allocation/freeing
iommu/amd: Free page-table in protection_domain_free()
iommu/amd: Allocate page-table in protection_domain_init()
iommu/amd: Let free_pagetable() not rely on domain->pt_root
iommu/amd: Unexport get_dev_data()
iommu/vt-d: Fix compile warning
iommu/vt-d: Remove real DMA lookup in find_domain
iommu/vt-d: Allocate domain info for real DMA sub-devices
iommu/vt-d: Only clear real DMA device's context entries
iommu: Remove iommu_sva_ops::mm_exit()
uacce: Remove mm_exit() op
iommu/sun50i: Constify sun50i_iommu_ops
iommu/hyper-v: Constify hyperv_ir_domain_ops
iommu/vt-d: Use pci_ats_supported()
iommu/arm-smmu-v3: Use pci_ats_supported()
...
After binding a device to an mm, device drivers currently need to
register a mm_exit handler. This function is called when the mm exits,
to gracefully stop DMA targeting the address space and flush page faults
to the IOMMU.
This is deemed too complex for the MMU release() notifier, which may be
triggered by any mmput() invocation, from about 120 callsites [1]. The
upcoming SVA module has an example of such complexity: the I/O Page
Fault handler would need to call mmput_async() instead of mmput() after
handling an IOPF, to avoid triggering the release() notifier which would
in turn drain the IOPF queue and lock up.
Another concern is the DMA stop function taking too long, up to several
minutes [2]. For some mmput() callers this may disturb other users. For
example, if the OOM killer picks the mm bound to a device as the victim
and that mm's memory is locked, if the release() takes too long, it
might choose additional innocent victims to kill.
To simplify the MMU release notifier, don't forward the notification to
device drivers. Since they don't stop DMA on mm exit anymore, the PASID
lifetime is extended:
(1) The device driver calls bind(). A PASID is allocated.
Here any DMA fault is handled by mm, and on error we don't print
anything to dmesg. Userspace can easily trigger errors by issuing DMA
on unmapped buffers.
(2) exit_mmap(), for example the process took a SIGKILL. This step
doesn't happen during normal operations. Remove the pgd from the
PASID table, since the page tables are about to be freed. Invalidate
the IOTLBs.
Here the device may still perform DMA on the address space. Incoming
transactions are aborted but faults aren't printed out. ATS
Translation Requests return Successful Translation Completions with
R=W=0. PRI Page Requests return with Invalid Request.
(3) The device driver stops DMA, possibly following release of a fd, and
calls unbind(). PASID table is cleared, IOTLB invalidated if
necessary. The page fault queues are drained, and the PASID is
freed.
If DMA for that PASID is still running here, something went seriously
wrong and errors should be reported.
For now remove iommu_sva_ops entirely. We might need to re-introduce
them at some point, for example to notify device drivers of unhandled
IOPF.
[1] https://lore.kernel.org/linux-iommu/20200306174239.GM31668@ziepe.ca/
[2] https://lore.kernel.org/linux-iommu/4d68da96-0ad5-b412-5987-2f7a6aa796c3@amd.com/
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20200423125329.782066-3-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
After moving iommu_group setup to iommu core code [1][2] and removing
private domain support in vt-d [3], there are no users for functions such
as iommu_request_dm_for_dev(), iommu_request_dma_domain_for_dev() and
request_default_domain_for_dev(). So, remove these functions.
[1] commit dce8d6964e ("iommu/amd: Convert to probe/release_device()
call-backs")
[2] commit e5d1841f18 ("iommu/vt-d: Convert to probe/release_device()
call-backs")
[3] commit 327d5b2fee ("iommu/vt-d: Allow 32bit devices to uses DMA
domain")
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20200513224721.20504-1-sai.praneeth.prakhya@intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
struct sg_table is a common structure used for describing a memory
buffer. It consists of a scatterlist with memory pages and DMA addresses
(sgl entry), as well as the number of scatterlist entries: CPU pages
(orig_nents entry) and DMA mapped pages (nents entry).
It turned out that it was a common mistake to misuse nents and orig_nents
entries, calling mapping functions with a wrong number of entries.
To avoid such issues, lets introduce a common wrapper operating directly
on the struct sg_table objects, which take care of the proper use of
the nents and orig_nents entries.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add call-backs to 'struct iommu_ops' as an alternative to the
add_device() and remove_device() call-backs, which will be removed when
all drivers are converted.
The new call-backs will not setup IOMMU groups and domains anymore,
so also add a probe_finalize() call-back where the IOMMU driver can do
per-device setup work which require the device to be set up with a
group and a domain.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20200429133712.31431-8-joro@8bytes.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Some devices are reqired to use a specific type (identity or dma)
of default domain when they are used with a vendor iommu. When the
system level default domain type is different from it, the vendor
iommu driver has to request a new default domain with
iommu_request_dma_domain_for_dev() and iommu_request_dm_for_dev()
in the add_dev() callback. Unfortunately, these two helpers only
work when the group hasn't been assigned to any other devices,
hence, some vendor iommu driver has to use a private domain if
it fails to request a new default one.
This adds def_domain_type() callback in the iommu_ops, so that
any special requirement of default domain for a device could be
aware by the iommu generic layer.
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
[ jroedel@suse.de: Added iommu_get_def_domain_type() function and use
it to allocate the default domain ]
Co-developed-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20200429133712.31431-3-joro@8bytes.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Although the 1-element array was a typical pre-C99 way to implement
variable-length structures, and indeed is a fundamental construct in the
APIs of certain other popular platforms, there's no good reason for it
here (and in particular the sizeof() trick is far too "clever" for its
own good). We can just as easily implement iommu_fwspec's preallocation
behaviour using a standard flexible array member, so let's make it look
the way most readers would expect.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
For platform devices that support SubstreamID (SSID), firmware provides
the number of supported SSID bits. Restrict it to what the SMMU supports
and cache it into master->ssid_bits, which will also be used for PCI
PASID.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Requiring each IOMMU driver to initialise the 'owner' field of their
'struct iommu_ops' is error-prone and easily forgotten. Follow the
example set by PCI and USB by assigning THIS_MODULE automatically when
registering the ops structure with IOMMU core.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Will Deacon <will@kernel.org>
Implement a generic function for removing reserved regions. This can be
used by drivers that don't do anything fancy with these regions other
than allocating memory for them.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
To avoid accidental removal of an active IOMMU driver module, take a
reference to the driver module in 'iommu_probe_device()' immediately
prior to invoking the '->add_device()' callback and hold it until the
after the device has been removed by '->remove_device()'.
Suggested-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Will Deacon <will@kernel.org>
Tested-by: John Garry <john.garry@huawei.com> # smmu v3
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
