These wrappers will be used to easily change the location of
the field later when all users are converted.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
With the flush queue infrastructure already abstracted into IOVA
domains, hooking it up in iommu-dma is pretty simple. Since there is a
degree of dependency on the IOMMU driver knowing what to do to play
along, we key the whole thing off a domain attribute which will be set
on default DMA ops domains to request non-strict invalidation. That way,
drivers can indicate the appropriate support by acknowledging the
attribute, and we can easily fall back to strict invalidation otherwise.
The flush queue callback needs a handle on the iommu_domain which owns
our cookie, so we have to add a pointer back to that, but neatly, that's
also sufficient to indicate whether we're using a flush queue or not,
and thus which way to release IOVAs. The only slight subtlety is
switching __iommu_dma_unmap() from calling iommu_unmap() to explicit
iommu_unmap_fast()/iommu_tlb_sync() so that we can elide the sync
entirely in non-strict mode.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
[rm: convert to domain attribute, tweak comments and commit message]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Since these are trivially handled by the .domain_{get,set}_attr
callbacks when relevant, we can streamline struct iommu_ops for
everyone.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
While iommu_get_domain_for_dev() is the robust way for arbitrary IOMMU
API callers to retrieve the domain pointer, for DMA ops domains it
doesn't scale well for large systems and multi-queue devices, since the
momentary refcount adjustment will lead to exclusive cacheline contention
when multiple CPUs are operating in parallel on different mappings for
the same device.
In the case of DMA ops domains, however, this refcounting is actually
unnecessary, since they already imply that the group exists and is
managed by platform code and IOMMU internals (by virtue of
iommu_group_get_for_dev()) such that a reference will already be held
for the lifetime of the device. Thus we can avoid the bottleneck by
providing a fast lookup specifically for the DMA code to retrieve the
default domain it already knows it has set up - a simple read-only
dereference plays much nicer with cache-coherency protocols.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Implement bus specific support for the fsl-mc bus including
registering arm_smmu_ops and bus specific device add operations.
Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
All iommu drivers use the default_iommu_map_sg implementation, and there
is no good reason to ever override it. Just expose it as iommu_map_sg
directly and remove the indirection, specially in our post-spectre world
where indirect calls are horribly expensive.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Provide base enablement for using debugfs to expose internal data of an
IOMMU driver. When called, create the /sys/kernel/debug/iommu directory.
Emit a strong warning at boot time to indicate that this feature is
enabled.
This function is called from iommu_init, and creates the initial DebugFS
directory. Drivers may then call iommu_debugfs_new_driver_dir() to
instantiate a device-specific directory to expose internal data.
It will return a pointer to the new dentry structure created in
/sys/kernel/debug/iommu, or NULL in the event of a failure.
Since the IOMMU driver can not be removed from the running system, there
is no need for an "off" function.
Signed-off-by: Gary R Hook <gary.hook@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Currently, iommu_unmap, iommu_unmap_fast and iommu_map_sg return
size_t. However, some of the return values are error codes (< 0),
which can be misinterpreted as large size. Therefore, returning size 0
instead to signify failure to map/unmap.
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The definition of map_sg was split during a recent addition to iommu_ops.
Put it back together.
Fixes: add02cfdc9 ("iommu: Introduce Interface for IOMMU TLB Flushing")
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
With the current IOMMU-API the hardware TLBs have to be
flushed in every iommu_ops->unmap() call-back.
For unmapping large amounts of address space, like it
happens when a KVM domain with assigned devices is
destroyed, this causes thousands of unnecessary TLB flushes
in the IOMMU hardware because the unmap call-back runs for
every unmapped physical page.
With the TLB Flush Interface and the new iommu_unmap_fast()
function introduced here the need to clean the hardware TLBs
is removed from the unmapping code-path. Users of
iommu_unmap_fast() have to explicitly call the TLB-Flush
functions to sync the page-table changes to the hardware.
Three functions for TLB-Flushes are introduced:
* iommu_flush_tlb_all() - Flushes all TLB entries
associated with that
domain. TLBs entries are
flushed when this function
returns.
* iommu_tlb_range_add() - This will add a given
range to the flush queue
for this domain.
* iommu_tlb_sync() - Flushes all queued ranges from
the hardware TLBs. Returns when
the flush is finished.
The semantic of this interface is intentionally similar to
the iommu_gather_ops from the io-pgtable code.
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This new call-back will be used to check if the domain attach need be
deferred for now. If yes, the domain attach/detach will return directly.
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The struct iommu_device has a 'struct device' embedded into
it, not as a pointer, but the whole struct. In the
conversion of the iommu drivers to use struct iommu_device
it was forgotten that the relase function for that struct
device simply calls kfree() on the pointer.
This frees memory that was never allocated and causes memory
corruption.
To fix this issue, use a pointer to struct device instead of
embedding the whole struct. This needs some updates in the
iommu sysfs code as well as the Intel VT-d and AMD IOMMU
driver.
Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Fixes: 39ab9555c2 ('iommu: Add sysfs bindings for struct iommu_device')
Cc: stable@vger.kernel.org # >= v4.11
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Commit 7d3002cc8c ("iommu/core: split mapping to page sizes as supported
by the hardware") replaced 'int gfp_order' with a 'size_t size' of
iommu_map / iommu_unmap function arguments, but missed the function
prototypes for the disabled CONFIG_IOMMU_API case, let's correct them
for consistency.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The function is in no fast-path, there is no need for it to
be static inline in a header file. This also removes the
need to include iommu trace-points in iommu.h.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
We make use of 'struct device' in iommu.h, so include
device.h to make it available explicitly.
Re-order the other headers while at it.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This is a fairly subtle thing - let's make sure it's described as
clearly as possible to avoid potential misunderstandings.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The introduction of reserved regions has left a couple of rough edges
which we could do with sorting out sooner rather than later. Since we
are not yet addressing the potential dynamic aspect of software-managed
reservations and presenting them at arbitrary fixed addresses, it is
incongruous that we end up displaying hardware vs. software-managed MSI
regions to userspace differently, especially since ARM-based systems may
actually require one or the other, or even potentially both at once,
(which iommu-dma currently has no hope of dealing with at all). Let's
resolve the former user-visible inconsistency ASAP before the ABI has
been baked into a kernel release, in a way that also lays the groundwork
for the latter shortcoming to be addressed by follow-up patches.
For clarity, rename the software-managed type to IOMMU_RESV_SW_MSI, use
IOMMU_RESV_MSI to describe the hardware type, and document everything a
little bit. Since the x86 MSI remapping hardware falls squarely under
this meaning of IOMMU_RESV_MSI, apply that type to their regions as well,
so that we tell the same story to userspace across all platforms.
Secondly, as the various region types require quite different handling,
and it really makes little sense to ever try combining them, convert the
bitfield-esque #defines to a plain enum in the process before anyone
gets the wrong impression.
Fixes: d30ddcaa7b ("iommu: Add a new type field in iommu_resv_region")
Reviewed-by: Eric Auger <eric.auger@redhat.com>
CC: Alex Williamson <alex.williamson@redhat.com>
CC: David Woodhouse <dwmw2@infradead.org>
CC: kvm@vger.kernel.org
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
And also move its remaining functionality to
iommu_device_register() and 'struct iommu_device'.
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
There is currently support for iommu sysfs bindings, but
those need to be implemented in the IOMMU drivers. Add a
more generic version of this by adding a struct device to
struct iommu_device and use that for the sysfs bindings.
Also convert the AMD and Intel IOMMU driver to make use of
it.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This struct represents one hardware iommu in the iommu core
code. For now it only has the iommu-ops associated with it,
but that will be extended soon.
The register/unregister interface is also added, as well as
making use of it in the Intel and AMD IOMMU drivers.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Rename the function to iommu_ops_from_fwnode(), because that
is what the function actually does. The new name is much
more descriptive about what the function does.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Introduce iommu_get_group_resv_regions whose role consists in
enumerating all devices from the group and collecting their
reserved regions. The list is sorted and overlaps between
regions of the same type are handled by merging the regions.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Introduce a new helper serving the purpose to allocate a reserved
region. This will be used in iommu driver implementing reserved
region callbacks.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
We introduce a new field to differentiate the reserved region
types and specialize the apply_resv_region implementation.
Legacy direct mapped regions have IOMMU_RESV_DIRECT type.
We introduce 2 new reserved memory types:
- IOMMU_RESV_MSI will characterize MSI regions that are mapped
- IOMMU_RESV_RESERVED characterize regions that cannot by mapped.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
We want to extend the callbacks used for dm regions and
use them for reserved regions. Reserved regions can be
- directly mapped regions
- regions that cannot be iommu mapped (PCI host bridge windows, ...)
- MSI regions (because they belong to another address space or because
they are not translated by the IOMMU and need special handling)
So let's rename the struct and also the callbacks.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Add the IOMMU_PRIV attribute, which is used to indicate privileged
mappings.
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The of_iommu_{set/get}_ops() API is used to associate a device
tree node with a specific set of IOMMU operations. The same
kernel interface is required on systems booting with ACPI, where
devices are not associated with a device tree node, therefore
the interface requires generalization.
The struct device fwnode member represents the fwnode token associated
with the device and the struct it points at is firmware specific;
regardless, it is initialized on both ACPI and DT systems and makes an
ideal candidate to use it to associate a set of IOMMU operations to a
given device, through its struct device.fwnode member pointer, paving
the way for representing per-device iommu_ops (ie an iommu instance
associated with a device).
Convert the DT specific of_iommu_{set/get}_ops() interface to
use struct device.fwnode as a look-up token, making the interface
usable on ACPI systems and rename the data structures and the
registration API so that they are made to represent their usage
more clearly.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Tomasz Nowicki <tn@semihalf.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Tomasz Nowicki <tn@semihalf.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
iommu_group_get_for_dev() expects that the IOMMU driver's device_group
callback return a group with a reference held for the given device.
Whilst allocating a new group is fine, and pci_device_group() correctly
handles reusing an existing group, there is no general means for IOMMU
drivers doing their own group lookup to take additional references on an
existing group pointer without having to also store device pointers or
resort to elaborate trickery.
Add an IOMMU-driver-specific function to fill the hole.
Acked-by: Sricharan R <sricharan@codeaurora.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Introduce a common structure to hold the per-device firmware data that
most IOMMU drivers need to keep track of. This enables us to configure
much of that data from common firmware code, and consolidate a lot of
the equivalent implementations, device look-up tables, etc. which are
currently strewn across IOMMU drivers.
This will also be enable us to address the outstanding "multiple IOMMUs
on the platform bus" problem by tweaking IOMMU API calls to prefer
dev->fwspec->ops before falling back to dev->bus->iommu_ops, and thus
gracefully handle those troublesome systems which we currently cannot.
As the first user, hook up the OF IOMMU configuration mechanism. The
driver-defined nature of DT cells means that we still need the drivers
to translate and add the IDs themselves, but future users such as the
much less free-form ACPI IORT will be much simpler and self-contained.
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This new call-back will be used by the iommu driver to do
reserve the given dm_region in its iova space before the
mapping is created.
The call-back is temporary until the dma-ops implementation
is part of the common iommu code.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Many IOMMUs support multiple page table formats, meaning that any given
domain may only support a subset of the hardware page sizes presented in
iommu_ops->pgsize_bitmap. There are also certain use-cases where the
creator of a domain may want to control which page sizes are used, for
example to force the use of hugepage mappings to reduce pagetable walk
depth.
To this end, add a per-domain pgsize_bitmap to represent the subset of
page sizes actually in use, to make it possible for domains with
different requirements to coexist.
Signed-off-by: Will Deacon <will.deacon@arm.com>
[rm: hijacked and rebased original patch with new commit message]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The priv field from iommu_ops is a hangover from the of_dma_configure
series and isn't actually used. Remove it before it has chance to
spread.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
On some platforms, MMIO regions might need slightly different treatment
compared to mapping regular memory; add the notion of MMIO mappings to
the IOMMU API's memory type flags, so that callers can let the IOMMU
drivers know to do the right thing.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu drivers that support the standard DT bindings use a of_xlate
callback pointer, but that is only part of struct iommu_ops when
CONFIG_OF_IOMMU is enabled, leading to build errors in randconfig
builds when that is not provided:
drivers/iommu/mtk_iommu.c:497:2: error: unknown field 'of_xlate' specified in initializer
.of_xlate = mtk_iommu_of_xlate,
^
drivers/iommu/mtk_iommu.c:497:14: error: initialization from incompatible pointer type [-Werror=incompatible-pointer-types]
.of_xlate = mtk_iommu_of_xlate,
^~~~~~~~~~~~~~~~~~
drivers/iommu/mtk_iommu.c:497:14: note: (near initialization for 'mtk_iommu_ops.domain_get_attr')
We can work around it by adding more #ifdefs in each driver, but
it seems nicer to just allow setting the pointer even if it is
unused. This makes the driver code look nicer, and it gives better
compile-time coverage when test building on other architectures.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 0df4fabe20 ("iommu/mediatek: Add mt8173 IOMMU driver")
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Update the comments around struct iommu_ops to match
current state and fix a few typos while at it.
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Rename that function to pci_device_group() and export it, so
that IOMMU drivers can use it as their device_group
call-back.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
That call-back is currently unused, change it into a
call-back function for finding the right IOMMU group for a
device.
This is a first step to remove the hard-coded PCI dependency
in the iommu-group code.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Taking inspiration from the existing arch/arm code, break out some
generic functions to interface the DMA-API to the IOMMU-API. This will
do the bulk of the heavy lifting for IOMMU-backed dma-mapping.
Since associating an IOVA allocator with an IOMMU domain is a fairly
common need, rather than introduce yet another private structure just to
do this for ourselves, extend the top-level struct iommu_domain with the
notion. A simple opaque cookie allows reuse by other IOMMU API users
with their various different incompatible allocator types.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Using __printf attributes helps to detect several format string issues
at compile time (even though -Wformat-security is currently disabled in
Makefile). For example it can detect when formatting a pointer as a
number, like the issue fixed in commit a3fa71c40f ("wl18xx: show
rx_frames_per_rates as an array as it really is"), or when the arguments
do not match the format string, c.f. for example commit 5ce1aca814
("reiserfs: fix __RASSERT format string").
To prevent similar bugs in the future, add a __printf attribute to every
function prototype which needs one in include/linux/ and lib/. These
functions were mostly found by using gcc's -Wsuggest-attribute=format
flag.
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This function can be called by an IOMMU driver to request
that a device's default domain is direct mapped.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Add two new functions to the IOMMU-API to allow the IOMMU
drivers to export the requirements for direct mapped regions
per device.
This is useful for exporting the information in Intel VT-d's
RMRR entries or AMD-Vi's unity mappings.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
All drivers have been converted to the new domain_alloc and
domain_free iommu-ops. So remove the old ones and get rid of
iommu_domain->priv too, as this is no longer needed when the
struct iommu_domain is embedded in the private structures of
the iommu drivers.
Tested-by: Thierry Reding <treding@nvidia.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This allows to handle domains differently based on their
type in the future. An IOMMU driver can implement certain
optimizations for DMA-API domains for example.
The domain types can be extended later and some of the
existing domain attributes can be migrated to become domain
flags.
Tested-by: Thierry Reding <treding@nvidia.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
These new call-backs defer the allocation and destruction of
'struct iommu_domain' to the iommu driver. This allows
drivers to embed this struct into their private domain
structures and to get rid of the domain_init and
domain_destroy call-backs when all drivers have been
converted.
Tested-by: Thierry Reding <treding@nvidia.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The iomm-config branch contains work from Will Deacon, quoting his description:
This series adds automatic IOMMU and DMA-mapping configuration for
OF-based DMA masters described using the generic IOMMU devicetree
bindings. Although there is plenty of future work around splitting up
iommu_ops, adding default IOMMU domains and sorting out automatic IOMMU
group creation for the platform_bus, this is already useful enough for
people to port over their IOMMU drivers and start using the new probing
infrastructure (indeed, Marek has patches queued for the Exynos IOMMU).
The branch touches core ARM and IOMMU driver files, and the respective
maintainers (Russell King and Joerg Roedel) agreed to have the contents
merged through the arm-soc tree. The final version was ready just before
the merge window, so we ended up delaying it a bit longer than the rest,
but we don't expect to see regressions because this is just additional
infrastructure that will get used in drivers starting in 3.20 but is
unused so far.
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Merge tag 'iommu-config-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC/iommu configuration update from Arnd Bergmann:
"The iomm-config branch contains work from Will Deacon, quoting his
description:
This series adds automatic IOMMU and DMA-mapping configuration for
OF-based DMA masters described using the generic IOMMU devicetree
bindings. Although there is plenty of future work around splitting up
iommu_ops, adding default IOMMU domains and sorting out automatic IOMMU
group creation for the platform_bus, this is already useful enough for
people to port over their IOMMU drivers and start using the new probing
infrastructure (indeed, Marek has patches queued for the Exynos IOMMU).
The branch touches core ARM and IOMMU driver files, and the respective
maintainers (Russell King and Joerg Roedel) agreed to have the
contents merged through the arm-soc tree.
The final version was ready just before the merge window, so we ended
up delaying it a bit longer than the rest, but we don't expect to see
regressions because this is just additional infrastructure that will
get used in drivers starting in 3.20 but is unused so far"
* tag 'iommu-config-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
iommu: store DT-probed IOMMU data privately
arm: dma-mapping: plumb our iommu mapping ops into arch_setup_dma_ops
arm: call iommu_init before of_platform_populate
dma-mapping: detect and configure IOMMU in of_dma_configure
iommu: fix initialization without 'add_device' callback
iommu: provide helper function to configure an IOMMU for an of master
iommu: add new iommu_ops callback for adding an OF device
dma-mapping: replace set_arch_dma_coherent_ops with arch_setup_dma_ops
iommu: provide early initialisation hook for IOMMU drivers
This patch adds a new function to the iommu_ops structure to allow an
OF device to be added to a specific IOMMU instance using the recently
merged generic devicetree binding for IOMMUs. The callback (of_xlate)
takes a struct device representing the master and an of_phandle_args
representing the IOMMU and the correspondong IDs for the new master.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
IOMMU drivers must be initialised before any of their upstream devices,
otherwise the relevant iommu_ops won't be configured for the bus in
question. To solve this, a number of IOMMU drivers use initcalls to
initialise the driver before anything has a chance to be probed.
Whilst this solves the immediate problem, it leaves the job of probing
the IOMMU completely separate from the iommu_ops to configure the IOMMU,
which are called on a per-bus basis and require the driver to figure out
exactly which instance of the IOMMU is being requested. In particular,
the add_device callback simply passes a struct device to the driver,
which then has to parse firmware tables or probe buses to identify the
relevant IOMMU instance.
This patch takes the first step in addressing this problem by adding an
early initialisation pass for IOMMU drivers, giving them the ability to
store some per-instance data in their iommu_ops structure and store that
in their of_node. This can later be used when parsing OF masters to
identify the IOMMU instance in question.
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Some IOMMUs accept an IOMMU_NOEXEC protection flag in addition to
IOMMU_READ and IOMMU_WRITE. Expose this as an IOMMU capability.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Exposing the XN flag of the SMMU driver as IOMMU_NOEXEC instead of
IOMMU_EXEC makes it enforceable, since for IOMMUs that don't support
the XN flag pages will always be executable.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Mapping and unmapping are more often than not in the critical path.
map_sg allows IOMMU driver implementations to optimize the process
of mapping buffers into the IOMMU page tables.
Instead of mapping a buffer one page at a time and requiring potentially
expensive TLB operations for each page, this function allows the driver
to map all pages in one go and defer TLB maintenance until after all
pages have been mapped.
Additionally, the mapping operation would be faster in general since
clients does not have to keep calling map API over and over again for
each physically contiguous chunk of memory that needs to be mapped to a
virtually contiguous region.
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This pull-request includes:
* Change in the IOMMU-API to convert the former iommu_domain_capable
function to just iommu_capable
* Various fixes in handling RMRR ranges for the VT-d driver (one fix
requires a device driver core change which was acked
by Greg KH)
* The AMD IOMMU driver now assigns and deassigns complete alias groups
to fix issues with devices using the wrong PCI request-id
* MMU-401 support for the ARM SMMU driver
* Multi-master IOMMU group support for the ARM SMMU driver
* Various other small fixes all over the place
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Merge tag 'iommu-updates-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
"This pull-request includes:
- change in the IOMMU-API to convert the former iommu_domain_capable
function to just iommu_capable
- various fixes in handling RMRR ranges for the VT-d driver (one fix
requires a device driver core change which was acked by Greg KH)
- the AMD IOMMU driver now assigns and deassigns complete alias
groups to fix issues with devices using the wrong PCI request-id
- MMU-401 support for the ARM SMMU driver
- multi-master IOMMU group support for the ARM SMMU driver
- various other small fixes all over the place"
* tag 'iommu-updates-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (41 commits)
iommu/vt-d: Work around broken RMRR firmware entries
iommu/vt-d: Store bus information in RMRR PCI device path
iommu/vt-d: Only remove domain when device is removed
driver core: Add BUS_NOTIFY_REMOVED_DEVICE event
iommu/amd: Fix devid mapping for ivrs_ioapic override
iommu/irq_remapping: Fix the regression of hpet irq remapping
iommu: Fix bus notifier breakage
iommu/amd: Split init_iommu_group() from iommu_init_device()
iommu: Rework iommu_group_get_for_pci_dev()
iommu: Make of_device_id array const
amd_iommu: do not dereference a NULL pointer address.
iommu/omap: Remove omap_iommu unused owner field
iommu: Remove iommu_domain_has_cap() API function
IB/usnic: Convert to use new iommu_capable() API function
vfio: Convert to use new iommu_capable() API function
kvm: iommu: Convert to use new iommu_capable() API function
iommu/tegra: Convert to iommu_capable() API function
iommu/msm: Convert to iommu_capable() API function
iommu/vt-d: Convert to iommu_capable() API function
iommu/fsl: Convert to iommu_capable() API function
...
Some IOMMUs, such as the ARM SMMU, support two stages of translation.
The idea behind such a scheme is to allow a guest operating system to
use the IOMMU for DMA mappings in the first stage of translation, with
the hypervisor then installing mappings in the second stage to provide
isolation of the DMA to the physical range assigned to that virtual
machine.
In order to allow IOMMU domains to be used for second-stage translation,
this patch adds a new iommu_attr (IOMMU_ATTR_NESTING) for setting
second-stage domains prior to device attach. The attribute can also be
queried to see if a domain is actually making use of nesting.
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This function will replace the current iommu_domain_has_cap
function and clean up the interface while at it.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
0-day kernel build testing reports:
arch/x86/kvm/x86.o: In function `iommu_device_destroy':
>> (.text+0x7a0a): multiple definition of `iommu_device_destroy'
arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x490): first defined here
arch/x86/kvm/x86.o: In function `iommu_device_link':
>> (.text+0x7a15): multiple definition of `iommu_device_link'
arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x49b): first defined here
arch/x86/kvm/x86.o: In function `iommu_device_unlink':
>> (.text+0x7a25): multiple definition of `iommu_device_unlink'
arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x4ab): first defined here
arch/x86/kvm/x86.o: In function `iommu_device_create':
>> (.text+0x79f8): multiple definition of `iommu_device_create'
arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x47e): first defined here
These are due to failing to define the stubs as static inline. Fix.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This structure is read-only data and should never be modified.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
IOMMUs currently have no common representation to userspace, most
seem to have no representation at all aside from a few printks
on bootup. There are however features of IOMMUs that are useful
to know about. For instance the IOMMU might support superpages,
making use of processor large/huge pages more important in a device
assignment scenario. It's also useful to create cross links between
devices and IOMMU hardware units, so that users might be able to
load balance their devices to avoid thrashing a single hardware unit.
This patch adds a device create and destroy interface as well as
device linking, making it very lightweight for an IOMMU driver to add
basic support. IOMMU drivers can provide additional attributes
automatically by using an attribute_group.
The attributes exposed are expected to be relatively device specific,
the means to retrieve them certainly are, so there are currently no
common attributes for the new class created here.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Currently each IOMMU driver that supports IOMMU groups has its own
code for discovering the base device used in grouping. This code
is generally not specific to the IOMMU hardware, but to the bus of
the devices managed by the IOMMU. We can therefore create a common
interface for supporting devices on different buses.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
domain_has_cap is a misnomer bc the func name should be
the same for CONFIG_IOMMU_API and !CONFIG_IOMMU_API.
Signed-off-by: Upinder Malhi <umalhi@cisco.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Almost every function in include/linux/iommu.h has an empty stub
but the iommu_group_get_by_id() did not get one by mistake.
This adds an empty stub for iommu_group_get_by_id() for IOMMU_API
disabled config.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Whilst most IOMMU mappings should probably be non-executable, there
may be cases (HSA?) where executable mappings are required.
This patch introduces a new mapping flag, IOMMU_EXEC, to indicate that
the mapping should be mapped as executable.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Change iommu driver call io_page_fault trace event. This iommu_error class
event can be enabled to trigger when an iommu error occurs. Trace information
includes driver name, device name, iova, and flags.
Testing:
Added trace calls to iommu_prepare_identity_map() for testing some of the
conditions that are hard to trigger. Here is the trace from the testing:
swapper/0-1 [003] .... 2.003774: io_page_fault: IOMMU:pci 0000:00:02.0 iova=0x00000000cb800000 flags=0x0002
swapper/0-1 [003] .... 2.004098: io_page_fault: IOMMU:pci 0000:00:1d.0 iova=0x00000000cadc6000 flags=0x0002
swapper/0-1 [003] .... 2.004115: io_page_fault: IOMMU:pci 0000:00:1a.0 iova=0x00000000cadc6000 flags=0x0002
swapper/0-1 [003] .... 2.004129: io_page_fault: IOMMU:pci 0000:00:1f.0 iova=0x0000000000000000 flags=0x0002
Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Added the following domain attributes for the FSL PAMU driver:
1. Added new iommu stash attribute, which allows setting of the
LIODN specific stash id parameter through IOMMU API.
2. Added an attribute for enabling/disabling DMA to a particular
memory window.
3. Added domain attribute to check for PAMUV1 specific constraints.
Signed-off-by: Varun Sethi <Varun.Sethi@freescale.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
As IOMMU groups are exposed to the user space by their numbers,
the user space can use them in various kernel APIs so the kernel
might need an API to find a group by its ID.
As an example, QEMU VFIO on PPC64 platform needs it to associate
a logical bus number (LIOBN) with a specific IOMMU group in order
to support in-kernel handling of DMA map/unmap requests.
The patch adds the iommu_group_get_by_id(id) function which performs
such search.
v2: fixed reference counting.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
The linux/iommu.h header uses ERR_PTR defined
in linux/err.h but doesn't include it.
Cc:joro@8bytes.org
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Each iommu window can have access permissions associated with it. Extended the
window_enable API to incorporate window access permissions.
In case of PAMU each window can have its specific set of permissions.
Signed-off-by: Varun Sethi <Varun.Sethi@freescale.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
This is required in case of PAMU, as it can support a window size of up
to 64G (even on 32bit).
Signed-off-by: Varun Sethi <Varun.Sethi@freescale.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Add the iommu_domain_window_enable() and iommu_domain_window_disable()
functions to the IOMMU-API. These functions will be used to setup
domains that are based on subwindows and not on paging.
Signed-off-by: Joerg Roedel <joro@8bytes.org>
This attribute of a domain can be queried to find out if the
domain supports setting up page-tables using the iommu_map()
and iommu_unmap() functions.
Signed-off-by: Joerg Roedel <joro@8bytes.org>
The 'struct notifier_block' is not used in linux/iommu.h but
not declared anywhere. Add a forward declaration for it.
Reported-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
The linux/iommu.h header uses types defined in linux/types.h but doesn't
include it.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
This patch introduces an extension to the iommu-api to get
and set attributes for an iommu_domain. Two functions are
introduced for this:
* iommu_domain_get_attr()
* iommu_domain_set_attr()
These functions will be used to make the iommu-api suitable
for GART-like IOMMUs and to implement hardware-specifc
api-extensions.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
IOMMU device groups are currently a rather vague associative notion
with assembly required by the user or user level driver provider to
do anything useful. This patch intends to grow the IOMMU group concept
into something a bit more consumable.
To do this, we first create an object representing the group, struct
iommu_group. This structure is allocated (iommu_group_alloc) and
filled (iommu_group_add_device) by the iommu driver. The iommu driver
is free to add devices to the group using it's own set of policies.
This allows inclusion of devices based on physical hardware or topology
limitations of the platform, as well as soft requirements, such as
multi-function trust levels or peer-to-peer protection of the
interconnects. Each device may only belong to a single iommu group,
which is linked from struct device.iommu_group. IOMMU groups are
maintained using kobject reference counting, allowing for automatic
removal of empty, unreferenced groups. It is the responsibility of
the iommu driver to remove devices from the group
(iommu_group_remove_device).
IOMMU groups also include a userspace representation in sysfs under
/sys/kernel/iommu_groups. When allocated, each group is given a
dynamically assign ID (int). The ID is managed by the core IOMMU group
code to support multiple heterogeneous iommu drivers, which could
potentially collide in group naming/numbering. This also keeps group
IDs to small, easily managed values. A directory is created under
/sys/kernel/iommu_groups for each group. A further subdirectory named
"devices" contains links to each device within the group. The iommu_group
file in the device's sysfs directory, which formerly contained a group
number when read, is now a link to the iommu group. Example:
$ ls -l /sys/kernel/iommu_groups/26/devices/
total 0
lrwxrwxrwx. 1 root root 0 Apr 17 12:57 0000:00:1e.0 ->
../../../../devices/pci0000:00/0000:00:1e.0
lrwxrwxrwx. 1 root root 0 Apr 17 12:57 0000:06:0d.0 ->
../../../../devices/pci0000:00/0000:00:1e.0/0000:06:0d.0
lrwxrwxrwx. 1 root root 0 Apr 17 12:57 0000:06:0d.1 ->
../../../../devices/pci0000:00/0000:00:1e.0/0000:06:0d.1
$ ls -l /sys/kernel/iommu_groups/26/devices/*/iommu_group
[truncating perms/owner/timestamp]
/sys/kernel/iommu_groups/26/devices/0000:00:1e.0/iommu_group ->
../../../kernel/iommu_groups/26
/sys/kernel/iommu_groups/26/devices/0000:06:0d.0/iommu_group ->
../../../../kernel/iommu_groups/26
/sys/kernel/iommu_groups/26/devices/0000:06:0d.1/iommu_group ->
../../../../kernel/iommu_groups/26
Groups also include several exported functions for use by user level
driver providers, for example VFIO. These include:
iommu_group_get(): Acquires a reference to a group from a device
iommu_group_put(): Releases reference
iommu_group_for_each_dev(): Iterates over group devices using callback
iommu_group_[un]register_notifier(): Allows notification of device add
and remove operations relevant to the group
iommu_group_id(): Return the group number
This patch also extends the IOMMU API to allow attaching groups to
domains. This is currently a simple wrapper for iterating through
devices within a group, but it's expected that the IOMMU API may
eventually make groups a more integral part of domains.
Groups intentionally do not try to manage group ownership. A user
level driver provider must independently acquire ownership for each
device within a group before making use of the group as a whole.
This may change in the future if group usage becomes more pervasive
across both DMA and IOMMU ops.
Groups intentionally do not provide a mechanism for driver locking
or otherwise manipulating driver matching/probing of devices within
the group. Such interfaces are generic to devices and beyond the
scope of IOMMU groups. If implemented, user level providers have
ready access via iommu_group_for_each_dev and group notifiers.
iommu_device_group() is removed here as it has no users. The
replacement is:
group = iommu_group_get(dev);
id = iommu_group_id(group);
iommu_group_put(group);
AMD-Vi & Intel VT-d support re-added in following patches.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Sometimes a single IOMMU user may have to deal with several
different IOMMU devices (e.g. remoteproc).
When an IOMMU fault happens, such users have to regain their
context in order to deal with the fault.
Users can't use the private fields of neither the iommu_domain nor
the IOMMU device, because those are already used by the IOMMU core
and low level driver (respectively).
This patch just simply allows users to pass a private token (most
notably their own context pointer) to iommu_set_fault_handler(),
and then makes sure it is provided back to the users whenever
an IOMMU fault happens.
The patch also adopts remoteproc to the new fault handling
interface, but the real functionality using this (recovery of
remote processors) will only be added later in a subsequent patch
set.
Cc: Fernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
An IOMMU group is a set of devices for which the IOMMU cannot
distinguish transactions. For PCI devices, a group often occurs
when a PCI bridge is involved. Transactions from any device
behind the bridge appear to be sourced from the bridge itself.
We leave it to the IOMMU driver to define the grouping restraints
for their platform.
Using this new interface, the group for a device can be retrieved
using the iommu_device_group() callback. Users will compare the
value returned against the value returned for other devices to
determine whether they are part of the same group. Devices with
no group are not translated by the IOMMU. There should be no
expectations about the group numbers as they may be arbitrarily
assigned by the IOMMU driver and may not be persistent across boots.
We also provide a sysfs interface to the group numbers here so
that userspace can understand IOMMU dependencies between devices
for managing safe, userspace drivers.
[Some code changes by Joerg Roedel <joerg.roedel@amd.com>]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Joerg Roedel