Although it's conceptually nice for the io_pgtable_cfg to provide a
standard VMSA TCR value, the reality is that no VMSA-compliant IOMMU
looks exactly like an Arm CPU, and they all have various other TCR
controls which io-pgtable can't be expected to understand. Thus since
there is an expectation that drivers will have to add to the given TCR
value anyway, let's strip it down to just the essentials that are
directly relevant to io-pgtable's inner workings - namely the various
sizes and the walk attributes.
Tested-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[will: Add missing include of bitfield.h]
Signed-off-by: Will Deacon <will@kernel.org>

TTBR1 values have so far been redundant since no users implement any
support for split address spaces. Crucially, though, one of the main
reasons for wanting to do so is to be able to manage each half entirely
independently, e.g. context-switching one set of mappings without
disturbing the other. Thus it seems unlikely that tying two tables
together in a single io_pgtable_cfg would ever be particularly desirable
or useful.

Streamline the configs to just a single conceptual TTBR value
representing the allocated table. This paves the way for future users to
support split address spaces by simply allocating a table and dealing
with the detailed TTBRn logistics themselves.
Tested-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[will: Drop change to ttbr value]
Signed-off-by: Will Deacon <will@kernel.org>

The CONFIG option controlling this driver, ARM_SMMU_V3,
depends on ARM64, which select's OF.

So, CONFIG_OF is always defined when building this driver.
of_match_ptr(arm_smmu_of_match) is the same as arm_smmu_of_match.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Will Deacon <will@kernel.org>

This is an off-by-one mistake.

resource_size() returns res->end - res->start + 1.
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Will Deacon <will@kernel.org>

CMDQ_OP_TLBI_NH_VA requires VMID and this was missing since
commit 1c27df1c ("iommu/arm-smmu: Use correct address mask
for CMD_TLBI_S2_IPA"). Add it back.

Fixes: 1c27df1c ("iommu/arm-smmu: Use correct address mask for CMD_TLBI_S2_IPA")
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
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>

I no longer work for Arm, so update the stale reference to my old email
address.
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>

By removing the redundant call to 'pci_request_acs()' we can allow the
ARM SMMUv3 driver to be built as a module.
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>

Add support for SMMU drivers built as modules to the ACPI/IORT device
probing path, by deferring the probe of the master if the SMMU driver is
known to exist but has not been loaded yet. Given that the IORT code
registers a platform device for each SMMU that it discovers, we can
easily trigger the udev based autoloading of the SMMU drivers by making
the platform device identifier part of the module alias.
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: John Garry <john.garry@huawei.com> # only manual smmu ko loading
Signed-off-by: Ard Biesheuvel <ardb@kernel.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>

When removing the SMMUv3 driver, we need to clear any state that we
registered during probe. This includes our bus ops, sysfs entries and
the IOMMU device registered for early firmware probing of masters.
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>

Forcefully unbinding the Arm SMMU drivers is a pretty dangerous operation,
since it will likely lead to catastrophic failure for any DMA devices
mastering through the SMMU being unbound. When the driver then attempts
to "handle" the fatal faults, it's very easy to trip over dead data
structures, leading to use-after-free.

On John's machine, he reports that the machine was "unusable" due to
loss of the storage controller following a forced unbind of the SMMUv3
driver:

  | # cd ./bus/platform/drivers/arm-smmu-v3
  | # echo arm-smmu-v3.0.auto > unbind
  | hisi_sas_v2_hw HISI0162:01: CQE_AXI_W_ERR (0x800) found!
  | platform arm-smmu-v3.0.auto: CMD_SYNC timeout at 0x00000146
  | [hwprod 0x00000146, hwcons 0x00000000]

Prevent this forced unbinding of the drivers by setting "suppress_bind_attrs"
to true.

Link: https://lore.kernel.org/lkml/06dfd385-1af0-3106-4cc5-6a5b8e864759@huawei.comReported-by: John Garry <john.garry@huawei.com>
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>

This reverts commit c07b6426.

Let's get the SMMUv3 driver building as a module, which means putting
back some dead code that we used to carry.
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>

Since commit 7723f4c5 ("driver core: platform: Add an error message
to platform_get_irq*()"), platform_get_irq_byname() displays an error
when the IRQ isn't found. Since the SMMUv3 driver uses that function to
query which interrupt method is available, the message is now displayed
during boot for any SMMUv3 that doesn't implement the combined
interrupt, or that implements MSIs.

[   20.700337] arm-smmu-v3 arm-smmu-v3.7.auto: IRQ combined not found
[   20.706508] arm-smmu-v3 arm-smmu-v3.7.auto: IRQ eventq not found
[   20.712503] arm-smmu-v3 arm-smmu-v3.7.auto: IRQ priq not found
[   20.718325] arm-smmu-v3 arm-smmu-v3.7.auto: IRQ gerror not found

Use platform_get_irq_byname_optional() to avoid displaying a spurious
error.

Fixes: 7723f4c5 ("driver core: platform: Add an error message to platform_get_irq*()")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Between VMSAv8-64 and the various 32-bit formats, there is either one
64-bit MAIR or a pair of 32-bit MAIR0/MAIR1 or NMRR/PMRR registers.
As such, keeping two 64-bit values in io_pgtable_cfg has always been
overkill.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

Add a gfp_t parameter to the iommu_ops::map function.
Remove the needless locking in the AMD iommu driver.

The iommu_ops::map function (or the iommu_map function which calls it)
was always supposed to be sleepable (according to Joerg's comment in
this thread: https://lore.kernel.org/patchwork/patch/977520/ ) and so
should probably have had a "might_sleep()" since it was written. However
currently the dma-iommu api can call iommu_map in an atomic context,
which it shouldn't do. This doesn't cause any problems because any iommu
driver which uses the dma-iommu api uses gfp_atomic in it's
iommu_ops::map function. But doing this wastes the memory allocators
atomic pools.
Signed-off-by: Tom Murphy <murphyt7@tcd.ie>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

If CONFIG_PCI_ATS is not set, building fails:

drivers/iommu/arm-smmu-v3.c: In function arm_smmu_ats_supported:
drivers/iommu/arm-smmu-v3.c:2325:35: error: struct pci_dev has no member named ats_cap; did you mean msi_cap?
  return !pdev->untrusted && pdev->ats_cap;
                                   ^~~~~~~

ats_cap should only used when CONFIG_PCI_ATS is defined,
so use #ifdef block to guard this.

Fixes: bfff88ec ("iommu/arm-smmu-v3: Rework enabling/disabling of ATS for PCI masters")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

This reverts commit b5e86196.

Now that ATC invalidation is performed in the correct places and without
incurring a locking overhead for non-ATS systems, we can re-enable the
corresponding SMMU feature detection.
Signed-off-by: Will Deacon <will@kernel.org>

When ATS is not in use, we can avoid taking the 'devices_lock' for the
domain on the invalidation path by simply caching the number of ATS
masters currently attached. The fiddly part is handling a concurrent
->attach() of an ATS-enabled master to a domain that is being
invalidated, but we can handle this using an 'smp_mb()' to ensure that
our check of the count is ordered after completion of our prior TLB
invalidation.

This also makes our ->attach() and ->detach() flows symmetric wrt ATS
interactions.
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

When invalidating the ATC for an PCIe endpoint using ATS, we must take
care to complete invalidation of the main SMMU TLBs beforehand, otherwise
the device could immediately repopulate its ATC with stale translations.

Hooking the ATC invalidation into ->unmap() as we currently do does the
exact opposite: it ensures that the ATC is invalidated *before*  the
main TLBs, which is bogus.

Move ATC invalidation into the actual (leaf) invalidation routines so
that it is always called after completing main TLB invalidation.
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

To prevent any potential issues arising from speculative Address
Translation Requests from an ATS-enabled PCIe endpoint, rework our ATS
enabling/disabling logic so that we enable ATS at the SMMU before we
enable it at the endpoint, and disable things in the opposite order.
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

Calling arm_smmu_tlb_inv_range() with a size of zero, perhaps due to
an empty 'iommu_iotlb_gather' structure, should be a NOP. Elide the
CMD_SYNC when there is no invalidation to be performed.
Signed-off-by: Will Deacon <will@kernel.org>

There's really no need for this to be a bitfield, particularly as we
don't have bitwise addressing on arm64.
Signed-off-by: Will Deacon <will@kernel.org>

Detecting the ATS capability of the SMMU at probe time introduces a
spinlock into the ->unmap() fast path, even when ATS is not actually
in use. Furthermore, the ATC invalidation that exists is broken, as it
occurs before invalidation of the main SMMU TLB which leaves a window
where the ATC can be repopulated with stale entries.

Given that ATS is both a new feature and a specialist sport, disable it
for now whilst we fix it properly in subsequent patches. Since PRI
requires ATS, disable that too.

Cc: <stable@vger.kernel.org>
Fixes: 9ce27afc ("iommu/arm-smmu-v3: Add support for PCI ATS")
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

It turns out that we've always relied on some subtle ordering guarantees
when inserting commands into the SMMUv3 command queue. With the recent
changes to elide locking when possible, these guarantees become more
subtle and even more important.

Add a comment documented the barrier semantics of command insertion so
that we don't have to derive the behaviour from scratch each time it
comes up on the list.
Signed-off-by: Will Deacon <will@kernel.org>

Update the iommu_iotlb_gather structure passed to ->tlb_add_page() and
use this information to defer all TLB invalidation until ->iotlb_sync().
This drastically reduces contention on the command queue, since we can
insert our commands in batches rather than one-by-one.
Tested-by: Ganapatrao Kulkarni  <gkulkarni@marvell.com>
Signed-off-by: Will Deacon <will@kernel.org>

The SMMU command queue is a bottleneck in large systems, thanks to the
spin_lock which serialises accesses from all CPUs to the single queue
supported by the hardware.

Attempt to improve this situation by moving to a new algorithm for
inserting commands into the queue, which is lock-free on the fast-path.
Tested-by: Ganapatrao Kulkarni  <gkulkarni@marvell.com>
Signed-off-by: Will Deacon <will@kernel.org>

Now that -Wimplicit-fallthrough is passed to GCC by default, the
following warning shows up:

../drivers/iommu/arm-smmu-v3.c: In function ‘arm_smmu_write_strtab_ent’:
../drivers/iommu/arm-smmu-v3.c:1189:7: warning: this statement may fall
 through [-Wimplicit-fallthrough=]
    if (disable_bypass)
       ^
../drivers/iommu/arm-smmu-v3.c:1191:3: note: here
   default:
   ^~~~~~~

Rework so that the compiler doesn't warn about fall-through. Make it
clearer by calling 'BUG_ON()' when disable_bypass is set, and always
'break;'
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Add a helper to match the firmware node handle of a device and provide
wrappers for {bus/class/driver}_find_device() APIs to avoid proliferation
of duplicate custom match functions.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: linux-usb@vger.kernel.org
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Joe Perches <joe@perches.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20190723221838.12024-4-suzuki.poulose@arm.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In preparation for rewriting the command queue insertion code to use a
new algorithm, rework many of our queue macro accessors and manipulation
functions so that they operate on the arm_smmu_ll_queue structure where
possible. This will allow us to call these helpers on local variables
without having to construct a full-blown arm_smmu_queue on the stack.

No functional change.
Tested-by: Ganapatrao Kulkarni  <gkulkarni@marvell.com>
Signed-off-by: Will Deacon <will@kernel.org>

In preparation for rewriting the command queue insertion code to use a
new algorithm, introduce a new arm_smmu_ll_queue structure which contains
only the information necessary to perform queue arithmetic for a queue
and will later be extended so that we can perform complex atomic
manipulation on some of the fields.

No functional change.
Tested-by: Ganapatrao Kulkarni  <gkulkarni@marvell.com>
Signed-off-by: Will Deacon <will@kernel.org>

The Q_OVF macro doesn't need to access the arm_smmu_queue structure, so
drop the unused macro argument.

No functional change.
Tested-by: Ganapatrao Kulkarni  <gkulkarni@marvell.com>
Signed-off-by: Will Deacon <will@kernel.org>

In preparation for rewriting the command queue insertion code to use a
new algorithm, separate the software and hardware views of the prod and
cons indexes so that manipulating the software state doesn't
automatically update the hardware state at the same time.

No functional change.
Tested-by: Ganapatrao Kulkarni  <gkulkarni@marvell.com>
Signed-off-by: Will Deacon <will@kernel.org>

With all the pieces in place, we can finally propagate the
iommu_iotlb_gather structure from the call to unmap() down to the IOMMU
drivers' implementation of ->tlb_add_page(). Currently everybody ignores
it, but the machinery is now there to defer invalidation.
Signed-off-by: Will Deacon <will@kernel.org>

Update the io-pgtable ->unmap() function to take an iommu_iotlb_gather
pointer as an argument, and update the callers as appropriate.
Signed-off-by: Will Deacon <will@kernel.org>

The ->tlb_sync() callback is no longer used, so it can be removed.
Signed-off-by: Will Deacon <will@kernel.org>

The ->tlb_add_flush() callback in the io-pgtable API now looks a bit
silly:

  - It takes a size and a granule, which are always the same
  - It takes a 'bool leaf', which is always true
  - It only ever flushes a single page

With that in mind, replace it with an optional ->tlb_add_page() callback
that drops the useless parameters.
Signed-off-by: Will Deacon <will@kernel.org>

Hook up ->tlb_flush_walk() and ->tlb_flush_leaf() in drivers using the
io-pgtable API so that we can start making use of them in the page-table
code. For now, they can just wrap the implementations of ->tlb_add_flush
and ->tlb_sync pending future optimisation in each driver.
Signed-off-by: Will Deacon <will@kernel.org>

To allow IOMMU drivers to batch up TLB flushing operations and postpone
them until ->iotlb_sync() is called, extend the prototypes for the
->unmap() and ->iotlb_sync() IOMMU ops callbacks to take a pointer to
the current iommu_iotlb_gather structure.

All affected IOMMU drivers are updated, but there should be no
functional change since the extra parameter is ignored for now.
Signed-off-by: Will Deacon <will@kernel.org>

In preparation for TLB flush gathering in the IOMMU API, rename the
iommu_gather_ops structure in io-pgtable to iommu_flush_ops, which
better describes its purpose and avoids the potential for confusion
between different levels of the API.

$ find linux/ -type f -name '*.[ch]' | xargs sed -i 's/gather_ops/flush_ops/g'
Signed-off-by: Will Deacon <will@kernel.org>

We make the invalid assumption in arm_smmu_detach_dev() that the ATC is
clear after calling pci_disable_ats(). For one thing, only enabling the
PCIe ATS capability constitutes an implicit invalidation event, so the
comment was wrong. More importantly, the ATS capability isn't necessarily
disabled by pci_disable_ats() in a PF, if the associated VFs have ATS
enabled. Explicitly invalidate all ATC entries in arm_smmu_detach_dev().
The endpoint cannot form new ATC entries because STE.EATS is clear.

Fixes: 9ce27afc ("iommu/arm-smmu-v3: Add support for PCI ATS")
Reported-by: Manoj Kumar <Manoj.Kumar3@arm.com>
Reported-by: Robin Murphy <Robin.Murphy@arm.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>