The sysfs interface for default domain types exists primarily so users
can choose the performance/security tradeoff relevant to their own
workload. As such, the choice between the policies for DMA domains fits
perfectly as an additional point on that scale - downgrading a
particular device from a strict default to non-strict may be enough to
let it reach the desired level of performance, while still retaining
more peace of mind than with a wide-open identity domain. Now that we've
abstracted non-strict mode as a distinct type of DMA domain, allow it to
be chosen through the user interface as well.
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/0e08da5ed4069fd3473cfbadda758ca983becdbf.1628682049.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Eliminate the iommu_get_dma_strict() indirection and pipe the
information through the domain type from the beginning. Besides
the flow simplification this also has several nice side-effects:
- Automatically implies strict mode for untrusted devices by
virtue of their IOMMU_DOMAIN_DMA override.
- Ensures that we only end up using flush queues for drivers
which are aware of them and can actually benefit.
- Allows us to handle flush queue init failure by falling back
to strict mode instead of leaving it to possibly blow up later.
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/47083d69155577f1367877b1594921948c366eb3.1628682049.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
IO_PGTABLE_QUIRK_NON_STRICT was never a very comfortable fit, since it's
not a quirk of the pagetable format itself. Now that we have a more
appropriate way to convey non-strict unmaps, though, this last of the
non-quirk quirks can also go, and with the flush queue code also now
enforcing its own ordering we can have a lovely cleanup all round.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/155b5c621cd8936472e273a8b07a182f62c6c20d.1628682049.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Since iommu_iotlb_gather exists to help drivers optimise flushing for a
given unmap request, it is also the logical place to indicate whether
the unmap is strict or not, and thus help them further optimise for
whether to expect a sync or a flush_all subsequently. As part of that,
it also seems fair to make the flush queue code take responsibility for
enforcing the really subtle ordering requirement it brings, so that we
don't need to worry about forgetting that if new drivers want to add
flush queue support, and can consolidate the existing versions.
While we're adding to the kerneldoc, also fill in some info for
@freelist which was overlooked previously.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/bf5f8e2ad84e48c712ccbf80fa8c610594c7595f.1628682049.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The pgsize bitmap is used to advertise the page sizes our hardware supports
to the IOMMU core, which will then use this information to split physically
contiguous memory regions it is mapping into page sizes that we support.
Traditionally the IOMMU core just handed us the mappings directly, after
making sure the size is an order of a 4KiB page and that the mapping has
natural alignment. To retain this behavior, we currently advertise that we
support all page sizes that are an order of 4KiB.
We are about to utilize the new IOMMU map/unmap_pages APIs. We could change
this to advertise the real page sizes we support.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210720020615.4144323-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
If people are going to insist on calling iommu_iova_to_phys()
pointlessly and expecting it to work, we can at least do ourselves a
favour by handling those cases in the core code, rather than repeatedly
across an inconsistent handful of drivers.
Since all the existing drivers implement the internal callback, and any
future ones are likely to want to work with iommu-dma which relies on
iova_to_phys a fair bit, we may as well remove that currently-redundant
check as well and consider it mandatory.
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/f564f3f6ff731b898ff7a898919bf871c2c7745a.1626354264.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Make IOMMU_DEFAULT_LAZY default for when AMD_IOMMU config is set, which
matches current behaviour.
For "fullflush" param, just call iommu_set_dma_strict(true) directly.
Since we get a strict vs lazy mode print already in iommu_subsys_init(),
and maintain a deprecation print when "fullflush" param is passed, drop the
prints in amd_iommu_init_dma_ops().
Finally drop global flag amd_iommu_unmap_flush, as it has no longer has any
purpose.
[jpg: Rebase for relocated file and drop amd_iommu_unmap_flush]
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1626088340-5838-6-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Make IOMMU_DEFAULT_LAZY default for when INTEL_IOMMU config is set,
as is current behaviour.
Also delete global flag intel_iommu_strict:
- In intel_iommu_setup(), call iommu_set_dma_strict(true) directly. Also
remove the print, as iommu_subsys_init() prints the mode and we have
already marked this param as deprecated.
- For cap_caching_mode() check in intel_iommu_setup(), call
iommu_set_dma_strict(true) directly; also reword the accompanying print
with a level downgrade and also add the missing '\n'.
- For Ironlake GPU, again call iommu_set_dma_strict(true) directly and
keep the accompanying print.
[jpg: Remove intel_iommu_strict]
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/1626088340-5838-5-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
As well as the default domain type, it's useful to know whether strict
or lazy for DMA domains, so add this info in a separate print.
The (stict/lazy) mode may be also set via iommu.strict earlyparm, but
this will be processed prior to iommu_subsys_init(), so that print will be
accurate for drivers which don't set the mode via custom means.
For the drivers which set the mode via custom means - AMD and Intel drivers
- they maintain prints to inform a change in policy or that custom cmdline
methods to change policy are deprecated.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/1626088340-5838-3-git-send-email-john.garry@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The 'addr_merge' parameter to iommu_pgsize() is a fabricated address
intended to describe the alignment requirements to consider when
choosing an appropriate page size. On the iommu_map() path, this address
is the logical OR of the virtual and physical addresses.
Subsequent improvements to iommu_pgsize() will need to check the
alignment of the virtual and physical components of 'addr_merge'
independently, so pass them in as separate parameters and reconstruct
'addr_merge' locally.
No functional change.
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>
Signed-off-by: Georgi Djakov <quic_c_gdjako@quicinc.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/1623850736-389584-7-git-send-email-quic_c_gdjako@quicinc.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Mapping memory into io-pgtables follows the same semantics
that unmapping memory used to follow (i.e. a buffer will be
mapped one page block per call to the io-pgtable code). This
means that it can be optimized in the same way that unmapping
memory was, so add a map_pages() callback to the io-pgtable
ops structure, so that a range of pages of the same size
can be mapped within the same call.
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Georgi Djakov <quic_c_gdjako@quicinc.com>
Link: https://lore.kernel.org/r/1623850736-389584-4-git-send-email-quic_c_gdjako@quicinc.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The io-pgtable code expects to operate on a single block or
granule of memory that is supported by the IOMMU hardware when
unmapping memory.
This means that when a large buffer that consists of multiple
such blocks is unmapped, the io-pgtable code will walk the page
tables to the correct level to unmap each block, even for blocks
that are virtually contiguous and at the same level, which can
incur an overhead in performance.
Introduce the unmap_pages() page table op to express to the
io-pgtable code that it should unmap a number of blocks of
the same size, instead of a single block. Doing so allows
multiple blocks to be unmapped in one call to the io-pgtable
code, reducing the number of page table walks, and indirect
calls.
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Georgi Djakov <quic_c_gdjako@quicinc.com>
Link: https://lore.kernel.org/r/1623850736-389584-2-git-send-email-quic_c_gdjako@quicinc.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
