Commit Graph

60 Commits

Author SHA1 Message Date
Linus Torvalds 6f51ee709e ARM: SoC/iommu configuration for 3.19
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
2014-12-16 14:53:01 -08:00
Robin Murphy 18f2340990 iommu: Decouple iommu_map_sg from CPU page size
If the IOMMU supports pages smaller than the CPU page size, segments
which lie at offsets within the CPU page may be mapped based on the
finer-grained IOMMU page boundaries. This minimises the amount of
non-buffer memory between the CPU page boundary and the start of the
segment which must be mapped and therefore exposed to the device, and
brings the default iommu_map_sg implementation in line with
iommu_map/unmap with respect to alignment.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-12-02 13:05:04 +01:00
Marek Szyprowski 461bfb3fe7 iommu: fix initialization without 'add_device' callback
IOMMU drivers can be initialized from of_iommu helpers. Such drivers don't
need to provide device_add callbacks to operate properly, so there is no
need to fail initialization if the callback is missing.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-12-01 16:50:41 +00:00
Heiko Stübner d7da6bdc32 iommu: Improve error handling when setting bus iommu
When some part of bus_set_iommu fails it should undo any made changes
and not simply leave everything as is.

This includes unregistering the bus notifier in iommu_bus_init when
add_iommu_group fails and also setting the bus->iommu_ops back to NULL.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-11-04 15:00:48 +01:00
Joerg Roedel 38ec010d9b iommu: Do more input validation in iommu_map_sg()
The IOMMU-API works on page boundarys, unlike the DMA-API
which can work with sub-page buffers. The sg->offset
field does not make sense on the IOMMU level, so force it to
be 0. Do some error-path consolidation while at it.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-11-04 14:53:51 +01:00
Olav Haugan 315786ebbf iommu: Add iommu_map_sg() function
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>
2014-11-04 14:53:36 +01:00
Mark Salter fb3e306515 iommu: Fix bus notifier breakage
iommu_bus_init() registers a bus notifier on the given bus by using
a statically defined notifier block:

  static struct notifier_block iommu_bus_nb = {
          .notifier_call = iommu_bus_notifier,
  };

This same notifier block is used for all busses. This causes a
problem for notifiers registered after iommu has registered this
callback on multiple busses. The problem is that a subsequent
notifier being registered on a bus which has this iommu notifier
will also get linked in to the notifier list of all other busses
which have this iommu notifier.

This patch fixes this by allocating the notifier_block at runtime.
Some error checking is also added to catch any allocation failure
or notifier registration error.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-09-25 16:46:37 +02:00
Alex Williamson f096c061f5 iommu: Rework iommu_group_get_for_pci_dev()
It turns out that our assumption that aliases are always to the same
slot isn't true.  One particular platform reports an IVRS alias of the
SATA controller (00:11.0) for the legacy IDE controller (00:14.1).
When we hit this, we attempt to use a single IOMMU group for
everything on the same bus, which in this case is the root complex.
We already have multiple groups defined for the root complex by this
point, resulting in multiple WARN_ON hits.

This patch makes these sorts of aliases work again with IOMMU groups
by reworking how we search through the PCI address space to find
existing groups.  This should also now handle looped dependencies and
all sorts of crazy inter-dependencies that we'll likely never see.

The recursion used here should never be very deep.  It's unlikely to
have individual aliases and only theoretical that we'd ever see a
chain where one alias causes us to search through to yet another
alias.  We're also only dealing with PCIe device on a single bus,
which means we'll typically only see multiple slots in use on the root
complex.  Loops are also a theoretically possibility, which I've
tested using fake DMA alias quirks and prevent from causing problems
using a bitmap of the devfn space that's been visited.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: stable@vger.kernel.org # 3.17
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-09-25 16:39:06 +02:00
Joerg Roedel 24278a24d8 iommu: Remove iommu_domain_has_cap() API function
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-09-25 15:48:09 +02:00
Joerg Roedel 3c0e0ca0a4 iommu: Introduce iommu_capable API function
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>
2014-09-25 15:44:49 +02:00
Joerg Roedel 1aed074869 iommu: Convert iommu-caps from define to enum
Allow compile-time type-checking.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-09-25 15:44:49 +02:00
Joerg Roedel c4a783b89e iommu/core: Make iommu_group_get_for_dev() more robust
When a non-PCI device is passed to that function it might
pass group == NULL to iommu_group_add_device() which then
dereferences it and cause a crash this way. Fix it by
just returning an error for non-PCI devices.

Fixes: 104a1c13ac
Cc: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-08-26 11:15:10 +02:00
Joerg Roedel 9db4ad9183 iommu/core: Check for the right function pointer in iommu_map()
Check for the ->map and not the ->unmap pointer.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-08-19 00:19:26 +02:00
Thierry Reding b22f6434cf iommu: Constify struct iommu_ops
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>
2014-07-07 10:36:59 +02:00
Alex Williamson 104a1c13ac iommu/core: Create central IOMMU group lookup/creation interface
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>
2014-07-04 12:35:58 +02:00
Joerg Roedel bb51eeee5a Merge branches 'iommu/fixes', 'tracing', 'core', 'arm/tegra', 'x86/vt-d', 'arm/smmu' and 'arm/shmobile' into next 2013-11-01 14:44:25 +01:00
Fabio Estevam abedb049c5 iommu: No need to pass '0x' when '%pa' is used
Commit 6197ca82 (iommu: Use %pa and %zx instead of casting) introduced the
usage of '%pa', but still kept the '0x', which leads to printing '0x0x'.

Remove the '0x' when '%pa' is used.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-09-24 14:43:38 +02:00
Shuah Khan 3a50639ca4 iommu: Change iommu driver to call unmap trace event
Change iommu driver to call unmap trace event. This iommu_map_unmap class
event can be enabled to trigger when iommu unmap iommu ops is called. Trace
information includes iova, physical address (map event only), and size.

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] ....     1.854102: unmap: IOMMU: iova=0x00000000cb800000 size=0x400

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-09-24 12:35:26 +02:00
Shuah Khan e0be7c8678 iommu: Change iommu driver to call map trace event
Change iommu driver to call map trace event. This iommu_map_unmap class event
can be enabled to trigger when iommu map iommu ops is called. Trace information
includes iova, physical address (map event only), and size.

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] ....     1.854102: map: IOMMU: iova=0x00000000cb800000 paddr=0x00000000cf9fffff size=0x400

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-09-24 12:35:26 +02:00
Shuah Khan 699806302d iommu: Change iommu driver to call detach_device_to_domain trace event
Change iommu driver to call detach_device_to_domain trace event. This
iommu_device class event can be enabled to trigger when devices are detached
from a domain. Trace information includes device name.

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] ....     1.854102: detach_device_from_domain: IOMMU: device=0000:00:02.0

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-09-24 12:35:26 +02:00
Shuah Khan b54db77885 iommu: Change iommu driver to call attach_device_to_domain trace event
Change iommu driver to call attach_device_to_domain trace event. This
iommu_device class event can be enabled to trigger when devices are attached
to a domain. Trace information includes device name.

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] ....     1.854102: attach_device_to_domain: IOMMU: device=0000:00:02.0

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-09-24 12:35:25 +02:00
Shuah Khan 2e757086bd iommu: Change iommu driver to call remove_device_to_group trace event
Change iommu driver to call remove_device_to_group trace event. This
iommu_group class event can be enabled to trigger when devices get
removed from an iommu group. Trace information includes iommu group id and
device name.

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] ....     1.854101: remove_device_from_group: IOMMU: groupID=0 device=0000:00:02.0

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-09-24 12:35:25 +02:00
Shuah Khan d1cf7e8227 iommu: Change iommu driver to call add_device_to_group trace event
Change iommu driver to call add_device_to_group trace event. This iommu_group
class event can be enabled to trigger when devices get added to an iommu group.
Trace information includes iommu group id and device name.

Testing:
The following is trace is generated when intel-iommu driver adds devices to
to iommu groups during boot-time during its initialization:

       swapper/0-1     [003] ....     1.854793: add_device_to_group: IOMMU: groupID=0 device=0000:00:00.0
       swapper/0-1     [003] ....     1.854797: add_device_to_group: IOMMU: groupID=1 device=0000:00:02.0

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-09-24 12:35:24 +02:00
Shuah Khan 7f6db17172 iommu: Add event tracing feature to iommu
Add tracing feature to iommu to report various iommu events. Classes
iommu_group, iommu_device, and iommu_map_unmap are defined.

iommu_group class events can be enabled to trigger when devices get added
to and removed from an iommu group. Trace information includes iommu group
id and device name.

iommu:add_device_to_group
iommu:remove_device_from_group

iommu_device class events can be enabled to trigger when devices are attached
to and detached from a domain. Trace information includes device name.

iommu:attach_device_to_domain
iommu:detach_device_from_domain

iommu_map_unmap class events can be enabled to trigger when iommu map and
unmap iommu ops. Trace information includes iova, physical address (map event
only), and size.

iommu:map
iommu:unmap

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-09-24 12:35:24 +02:00
Joe Perches 6197ca8272 iommu: Use %pa and %zx instead of casting
printk supports using %pa for phys_addr_t and
%zx for size_t so use those instead of %lx and
casts to unsigned long.

Other miscellaneous changes around this:

Always use 0x%zx for size instead of one use of decimal.
Coalesce format and align arguments.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-06-24 12:31:49 +02:00
Alex Williamson c6a8af50b8 iommu: Fix compiler warning on pr_debug
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-06-23 13:48:10 +02:00
Alex Williamson bd13969b95 iommu: Split iommu_unmaps
iommu_map splits requests into pages that the iommu driver reports
that it can handle.  The iommu_unmap path does not do the same.  This
can cause problems not only from callers that might expect the same
behavior as the map path, but even from the failure path of iommu_map,
should it fail at a point where it has mapped and needs to unwind a
set of pages that the iommu driver cannot handle directly.  amd_iommu,
for example, will BUG_ON if asked to unmap a non power of 2 size.

Fix this by extracting and generalizing the sizing code from the
iommu_map path and use it for both map and unmap.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-06-20 17:26:25 +02:00
Joerg Roedel 0c4513be3d Merge branches 'iommu/fixes', 'x86/vt-d', 'x86/amd', 'ppc/pamu', 'core' and 'arm/tegra' into next 2013-05-02 12:10:19 +02:00
Alexey Kardashevskiy aa16bea929 iommu: Add a function to find an iommu group by id
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>
2013-04-24 19:56:51 +02:00
Varun Sethi 80f97f0f73 iommu/fsl: Add the window permission flag as a parameter to iommu_window_enable API.
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>
2013-04-02 18:20:53 +02:00
Varun Sethi bb5547acfc iommu/fsl: Make iova dma_addr_t in the iommu_iova_to_phys API.
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>
2013-04-02 18:20:53 +02:00
Joerg Roedel 693567125b iommu: Add DOMAIN_ATTR_WINDOWS domain attribute
This attribute can be used to set and get the number of
subwindows on IOMMUs that are window-based.

Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-02-06 10:47:28 +01:00
Joerg Roedel d7787d579c iommu: Add domain window handling functions
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>
2013-02-06 10:47:22 +01:00
Joerg Roedel d2e1216016 iommu: Implement DOMAIN_ATTR_PAGING attribute
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>
2013-02-06 10:47:11 +01:00
Joerg Roedel 57886518a8 iommu: Check for valid pgsize_bitmap in iommu_map/unmap
In case the page-size bitmap is zero the code path in
iommu_map and iommu_unmap is undefined. Make it defined and
return -ENODEV in this case.

Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-02-06 10:47:05 +01:00
Alexey Kardashevskiy 097e3635dc iommu: moving initialization earlier
The iommu_init() initializes IOMMU internal structures and data
required for the IOMMU API as iommu_group_alloc().
It is registered as a subsys_initcall now.

One of the IOMMU users is going to be a PCI subsystem on POWER.
It discovers new IOMMU tables during the PCI scan so the logical
place to call iommu_group_alloc() is the moment when a new group
is discovered. However PCI scan is done from subsys_initcall hook
as IOMMU does so PCI hook can be (and is) called before the IOMMU one.

The patch moves IOMMU subsystem initialization one step earlier
to make sure that IOMMU is initialized before PCI scan begins.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
2013-01-10 18:07:53 +01:00
Joerg Roedel 395e51f18d Merge branches 'iommu/fixes', 'x86/amd', 'groups', 'arm/tegra' and 'api/domain-attr' into next
Conflicts:
	drivers/iommu/iommu.c
	include/linux/iommu.h
2012-07-23 12:17:00 +02:00
Joerg Roedel 0ff64f80e0 iommu/amd: Implement DOMAIN_ATTR_GEOMETRY attribute
Implement the attribute itself and add the code for the
AMD IOMMU driver.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-07-11 12:15:45 +02:00
Joerg Roedel 0cd76dd13b iommu: Add domain-attribute handlers
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>
2012-07-11 12:12:14 +02:00
Alex Williamson d72e31c937 iommu: IOMMU Groups
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>
2012-06-25 13:48:15 +02:00
Ohad Ben-Cohen 77ca233235 iommu/core: pass a user-provided token to fault handlers
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>
2012-05-22 18:08:08 +02:00
Joerg Roedel f93ea73387 Merge branches 'iommu/page-sizes' and 'iommu/group-id' into next
Conflicts:
	drivers/iommu/amd_iommu.c
	drivers/iommu/intel-iommu.c
	include/linux/iommu.h
2012-01-09 13:06:28 +01:00
Joerg Roedel 00fb5430f5 Merge branches 'iommu/fixes', 'arm/omap' and 'x86/amd' into next
Conflicts:
	drivers/pci/hotplug/acpiphp_glue.c
2012-01-09 13:04:05 +01:00
KyongHo Cho 8bd6960c6a iommu: Initialize domain->handler in iommu_domain_alloc()
Since it is not guaranteed that an iommu driver initializes in its
domain_init() function, it must be initialized with NULL to prevent
calling a function in an arbitrary location when iommu fault occurred.

Signed-off-by: KyongHo Cho <pullip.cho@samsung.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-12-16 15:05:13 +01:00
Alex Williamson 1460432cb5 iommu: Add iommu_device_group callback and iommu_group sysfs entry
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>
2011-11-15 12:22:23 +01:00
Ohad Ben-Cohen 6c274d1cd5 iommu/core: remove the temporary pgsize settings
Now that all IOMMU drivers are exporting their supported pgsizes,
we can remove the default pgsize settings in register_iommu().

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-11-10 11:40:38 +01:00
Ohad Ben-Cohen 7d3002cc8c iommu/core: split mapping to page sizes as supported by the hardware
When mapping a memory region, split it to page sizes as supported
by the iommu hardware. Always prefer bigger pages, when possible,
in order to reduce the TLB pressure.

The logic to do that is now added to the IOMMU core, so neither the iommu
drivers themselves nor users of the IOMMU API have to duplicate it.

This allows a more lenient granularity of mappings; traditionally the
IOMMU API took 'order' (of a page) as a mapping size, and directly let
the low level iommu drivers handle the mapping, but now that the IOMMU
core can split arbitrary memory regions into pages, we can remove this
limitation, so users don't have to split those regions by themselves.

Currently the supported page sizes are advertised once and they then
remain static. That works well for OMAP and MSM but it would probably
not fly well with intel's hardware, where the page size capabilities
seem to have the potential to be different between several DMA
remapping devices.

register_iommu() currently sets a default pgsize behavior, so we can convert
the IOMMU drivers in subsequent patches. After all the drivers
are converted, the temporary default settings will be removed.

Mainline users of the IOMMU API (kvm and omap-iovmm) are adopted
to deal with bytes instead of page order.

Many thanks to Joerg Roedel <Joerg.Roedel@amd.com> for significant review!

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: David Brown <davidb@codeaurora.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <Joerg.Roedel@amd.com>
Cc: Stepan Moskovchenko <stepanm@codeaurora.org>
Cc: KyongHo Cho <pullip.cho@samsung.com>
Cc: Hiroshi DOYU <hdoyu@nvidia.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-11-10 11:40:37 +01:00
Ohad Ben-Cohen 5009065d38 iommu/core: stop converting bytes to page order back and forth
Express sizes in bytes rather than in page order, to eliminate the
size->order->size conversions we have whenever the IOMMU API is calling
the low level drivers' map/unmap methods.

Adopt all existing drivers.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Cc: David Brown <davidb@codeaurora.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <Joerg.Roedel@amd.com>
Cc: Stepan Moskovchenko <stepanm@codeaurora.org>
Cc: KyongHo Cho <pullip.cho@samsung.com>
Cc: Hiroshi DOYU <hdoyu@nvidia.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-11-10 11:40:37 +01:00
Joerg Roedel 1abb4ba596 Merge branches 'amd/fixes', 'debug/dma-api', 'arm/omap', 'arm/msm', 'core', 'iommu/fault-reporting' and 'api/iommu-ops-per-bus' into next
Conflicts:
	drivers/iommu/amd_iommu.c
	drivers/iommu/iommu.c
2011-10-21 14:38:55 +02:00
Joerg Roedel 94441c3bd9 iommu/core: Remove global iommu_ops and register_iommu
With all IOMMU drivers being converted to bus_set_iommu the
global iommu_ops are no longer required. The same is true
for the deprecated register_iommu function.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2011-10-21 14:37:23 +02:00