Commit Graph

175 Commits

Author SHA1 Message Date
Joerg Roedel 5fa9e7c5fa iommu: Print default domain type on boot
Introduce a subsys_initcall for IOMMU code and use it to
print the default domain type at boot.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-23 10:11:28 +02:00
Joerg Roedel adab0b07cb iommu: Use Functions to set default domain type in iommu_set_def_domain_type()
There are functions now to set the default domain type which
take care of updating other necessary state. Don't open-code
it in iommu_set_def_domain_type() and use those functions
instead.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-23 10:09:58 +02:00
Joerg Roedel 8a69961c7f iommu: Add helpers to set/get default domain type
Add a couple of functions to allow changing the default
domain type from architecture code and a function for iommu
drivers to request whether the default domain is
passthrough.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-23 10:09:58 +02:00
Joerg Roedel faf1498993 iommu: Remember when default domain type was set on kernel command line
Introduce an extensible concept to remember when certain
configuration settings for the IOMMU code have been set on
the kernel command line.

This will be used later to prevent overwriting these
settings with other defaults.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-23 10:09:58 +02:00
Will Deacon 56f8af5e9d iommu: Pass struct iommu_iotlb_gather to ->unmap() and ->iotlb_sync()
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>
2019-07-29 17:22:52 +01:00
Will Deacon a7d20dc19d iommu: Introduce struct iommu_iotlb_gather for batching TLB flushes
To permit batching of TLB flushes across multiple calls to the IOMMU
driver's ->unmap() implementation, introduce a new structure for
tracking the address range to be flushed and the granularity at which
the flushing is required.

This is hooked into the IOMMU API and its caller are updated to make use
of the new structure. Subsequent patches will plumb this into the IOMMU
drivers as well, but for now the gathering information is ignored.

Signed-off-by: Will Deacon <will@kernel.org>
2019-07-24 13:35:27 +01:00
Will Deacon 6d1bcb957b iommu: Remove empty iommu_tlb_range_add() callback from iommu_ops
Commit add02cfdc9 ("iommu: Introduce Interface for IOMMU TLB Flushing")
added three new TLB flushing operations to the IOMMU API so that the
underlying driver operations can be batched when unmapping large regions
of IO virtual address space.

However, the ->iotlb_range_add() callback has not been implemented by
any IOMMU drivers (amd_iommu.c implements it as an empty function, which
incurs the overhead of an indirect branch). Instead, drivers either flush
the entire IOTLB in the ->iotlb_sync() callback or perform the necessary
invalidation during ->unmap().

Attempting to implement ->iotlb_range_add() for arm-smmu-v3.c revealed
two major issues:

  1. The page size used to map the region in the page-table is not known,
     and so it is not generally possible to issue TLB flushes in the most
     efficient manner.

  2. The only mutable state passed to the callback is a pointer to the
     iommu_domain, which can be accessed concurrently and therefore
     requires expensive synchronisation to keep track of the outstanding
     flushes.

Remove the callback entirely in preparation for extending ->unmap() and
->iotlb_sync() to update a token on the caller's stack.

Signed-off-by: Will Deacon <will@kernel.org>
2019-07-24 13:32:33 +01:00
Joerg Roedel d95c388586 Merge branches 'x86/vt-d', 'x86/amd', 'arm/smmu', 'arm/omap', 'generic-dma-ops' and 'core' into next 2019-07-04 17:26:48 +02:00
Linus Torvalds c78ad1be4b IOMMU Fixes for Linux v5.2-rc4
Including:
 
 	- Three Fixes for Intel VT-d to fix a potential dead-lock, a
 	  formatting fix and a bit setting fix.
 
 	- One fix for the ARM-SMMU to make it work on some platforms
 	  with sub-optimal SMMU emulation.
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Merge tag 'iommu-fixes-v5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu fixes from Joerg Roedel:

 - three fixes for Intel VT-d to fix a potential dead-lock, a formatting
   fix and a bit setting fix

 - one fix for the ARM-SMMU to make it work on some platforms with
   sub-optimal SMMU emulation

* tag 'iommu-fixes-v5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/arm-smmu: Avoid constant zero in TLBI writes
  iommu/vt-d: Set the right field for Page Walk Snoop
  iommu/vt-d: Fix lock inversion between iommu->lock and device_domain_lock
  iommu: Add missing new line for dma type
2019-06-14 05:49:35 -10:00
Eric Auger adfd373820 iommu: Introduce IOMMU_RESV_DIRECT_RELAXABLE reserved memory regions
Introduce a new type for reserved region. This corresponds
to directly mapped regions which are known to be relaxable
in some specific conditions, such as device assignment use
case. Well known examples are those used by USB controllers
providing PS/2 keyboard emulation for pre-boot BIOS and
early BOOT or RMRRs associated to IGD working in legacy mode.

Since commit c875d2c1b8 ("iommu/vt-d: Exclude devices using RMRRs
from IOMMU API domains") and commit 18436afdc1 ("iommu/vt-d: Allow
RMRR on graphics devices too"), those regions are currently
considered "safe" with respect to device assignment use case
which requires a non direct mapping at IOMMU physical level
(RAM GPA -> HPA mapping).

Those RMRRs currently exist and sometimes the device is
attempting to access it but this has not been considered
an issue until now.

However at the moment, iommu_get_group_resv_regions() is
not able to make any difference between directly mapped
regions: those which must be absolutely enforced and those
like above ones which are known as relaxable.

This is a blocker for reporting severe conflicts between
non relaxable RMRRs (like MSI doorbells) and guest GPA space.

With this new reserved region type we will be able to use
iommu_get_group_resv_regions() to enumerate the IOVA space
that is usable through the IOMMU API without introducing
regressions with respect to existing device assignment
use cases (USB and IGD).

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-06-12 10:32:59 +02:00
Eric Auger ad0834deda iommu: Fix a leak in iommu_insert_resv_region
In case we expand an existing region, we unlink
this latter and insert the larger one. In
that case we should free the original region after
the insertion. Also we can immediately return.

Fixes: 6c65fb318e ("iommu: iommu_get_group_resv_regions")

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-06-12 10:32:23 +02:00
Jean-Philippe Brucker bf3255b3cf iommu: Add recoverable fault reporting
Some IOMMU hardware features, for example PCI PRI and Arm SMMU Stall,
enable recoverable I/O page faults. Allow IOMMU drivers to report PRI Page
Requests and Stall events through the new fault reporting API. The
consumer of the fault can be either an I/O page fault handler in the host,
or a guest OS.

Once handled, the fault must be completed by sending a page response back
to the IOMMU. Add an iommu_page_response() function to complete a page
fault.

There are two ways to extend the userspace API:
* Add a field to iommu_page_response and a flag to
  iommu_page_response::flags describing the validity of this field.
* Introduce a new iommu_page_response_X structure with a different version
  number. The kernel must then support both versions.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-06-12 10:19:06 +02:00
Jacob Pan 0c830e6b32 iommu: Introduce device fault report API
Traditionally, device specific faults are detected and handled within
their own device drivers. When IOMMU is enabled, faults such as DMA
related transactions are detected by IOMMU. There is no generic
reporting mechanism to report faults back to the in-kernel device
driver or the guest OS in case of assigned devices.

This patch introduces a registration API for device specific fault
handlers. This differs from the existing iommu_set_fault_handler/
report_iommu_fault infrastructures in several ways:
- it allows to report more sophisticated fault events (both
  unrecoverable faults and page request faults) due to the nature
  of the iommu_fault struct
- it is device specific and not domain specific.

The current iommu_report_device_fault() implementation only handles
the "shoot and forget" unrecoverable fault case. Handling of page
request faults or stalled faults will come later.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-06-12 10:19:06 +02:00
Thomas Gleixner 4505153954 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation inc 59 temple place suite 330 boston ma 02111
  1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 136 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:06 +02:00
Lu Baolu 7423e01741 iommu: Add API to request DMA domain for device
Normally during iommu probing a device, a default doamin will
be allocated and attached to the device. The domain type of
the default domain is statically defined, which results in a
situation where the allocated default domain isn't suitable
for the device due to some limitations. We already have API
iommu_request_dm_for_dev() to replace a DMA domain with an
identity one. This adds iommu_request_dma_domain_for_dev()
to request a dma domain if an allocated identity domain isn't
suitable for the device in question.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-05-27 16:56:43 +02:00
Lu Baolu 57274ea257 iommu: Use right function to get group for device
The iommu_group_get_for_dev() will allocate a group for a
device if it isn't in any group. This isn't the use case
in iommu_request_dm_for_dev(). Let's use iommu_group_get()
instead.

Fixes: d290f1e70d ("iommu: Introduce iommu_request_dm_for_dev()")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-05-27 16:30:59 +02:00
Lu Baolu 24f307d8ab iommu: Add missing new line for dma type
So that all types are printed in the same format.

Fixes: c52c72d3de ("iommu: Add sysfs attribyte for domain type")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-05-27 16:15:16 +02:00
Joerg Roedel b5531563e8 Merge branches 'arm/tegra', 'arm/mediatek', 'arm/smmu', 'x86/vt-d', 'x86/amd' and 'core' into next 2019-05-07 09:40:12 +02:00
Jean-Philippe Brucker 26b25a2b98 iommu: Bind process address spaces to devices
Add bind() and unbind() operations to the IOMMU API.
iommu_sva_bind_device() binds a device to an mm, and returns a handle to
the bond, which is released by calling iommu_sva_unbind_device().

Each mm bound to devices gets a PASID (by convention, a 20-bit system-wide
ID representing the address space), which can be retrieved with
iommu_sva_get_pasid(). When programming DMA addresses, device drivers
include this PASID in a device-specific manner, to let the device access
the given address space. Since the process memory may be paged out, device
and IOMMU must support I/O page faults (e.g. PCI PRI).

Using iommu_sva_set_ops(), device drivers provide an mm_exit() callback
that is called by the IOMMU driver if the process exits before the device
driver called unbind(). In mm_exit(), device driver should disable DMA
from the given context, so that the core IOMMU can reallocate the PASID.
Whether the process exited or nor, the device driver should always release
the handle with unbind().

To use these functions, device driver must first enable the
IOMMU_DEV_FEAT_SVA device feature with iommu_dev_enable_feature().

Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-04-11 17:08:52 +02:00
Lu Baolu a3a195929d iommu: Add APIs for multiple domains per device
Sharing a physical PCI device in a finer-granularity way
is becoming a consensus in the industry. IOMMU vendors
are also engaging efforts to support such sharing as well
as possible. Among the efforts, the capability of support
finer-granularity DMA isolation is a common requirement
due to the security consideration. With finer-granularity
DMA isolation, subsets of a PCI function can be isolated
from each others by the IOMMU. As a result, there is a
request in software to attach multiple domains to a physical
PCI device. One example of such use model is the Intel
Scalable IOV [1] [2]. The Intel vt-d 3.0 spec [3] introduces
the scalable mode which enables PASID granularity DMA
isolation.

This adds the APIs to support multiple domains per device.
In order to ease the discussions, we call it 'a domain in
auxiliary mode' or simply 'auxiliary domain' when multiple
domains are attached to a physical device.

The APIs include:

* iommu_dev_has_feature(dev, IOMMU_DEV_FEAT_AUX)
  - Detect both IOMMU and PCI endpoint devices supporting
    the feature (aux-domain here) without the host driver
    dependency.

* iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX)
  - Check the enabling status of the feature (aux-domain
    here). The aux-domain interfaces are available only
    if this returns true.

* iommu_dev_enable/disable_feature(dev, IOMMU_DEV_FEAT_AUX)
  - Enable/disable device specific aux-domain feature.

* iommu_aux_attach_device(domain, dev)
  - Attaches @domain to @dev in the auxiliary mode. Multiple
    domains could be attached to a single device in the
    auxiliary mode with each domain representing an isolated
    address space for an assignable subset of the device.

* iommu_aux_detach_device(domain, dev)
  - Detach @domain which has been attached to @dev in the
    auxiliary mode.

* iommu_aux_get_pasid(domain, dev)
  - Return ID used for finer-granularity DMA translation.
    For the Intel Scalable IOV usage model, this will be
    a PASID. The device which supports Scalable IOV needs
    to write this ID to the device register so that DMA
    requests could be tagged with a right PASID prefix.

This has been updated with the latest proposal from Joerg
posted here [5].

Many people involved in discussions of this design.

Kevin Tian <kevin.tian@intel.com>
Liu Yi L <yi.l.liu@intel.com>
Ashok Raj <ashok.raj@intel.com>
Sanjay Kumar <sanjay.k.kumar@intel.com>
Jacob Pan <jacob.jun.pan@linux.intel.com>
Alex Williamson <alex.williamson@redhat.com>
Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Joerg Roedel <joro@8bytes.org>

and some discussions can be found here [4] [5].

[1] https://software.intel.com/en-us/download/intel-scalable-io-virtualization-technical-specification
[2] https://schd.ws/hosted_files/lc32018/00/LC3-SIOV-final.pdf
[3] https://software.intel.com/en-us/download/intel-virtualization-technology-for-directed-io-architecture-specification
[4] https://lkml.org/lkml/2018/7/26/4
[5] https://www.spinics.net/lists/iommu/msg31874.html

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Suggested-by: Kevin Tian <kevin.tian@intel.com>
Suggested-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Suggested-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-04-11 17:02:51 +02:00
Lu Baolu 8cec63e529 iommu: Remove iommu_callback_data
The iommu_callback_data is not used anywhere, remove it to make
the code more concise.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-03-25 14:43:12 +01:00
Joerg Roedel 8bc32a2856 iommu: Don't print warning when IOMMU driver only supports unmanaged domains
Print the warning about the fall-back to IOMMU_DOMAIN_DMA in
iommu_group_get_for_dev() only when such a domain was
actually allocated.

Otherwise the user will get misleading warnings in the
kernel log when the iommu driver used doesn't support
IOMMU_DOMAIN_DMA and IOMMU_DOMAIN_IDENTITY.

Fixes: fccb4e3b8a ('iommu: Allow default domain type to be set on the kernel command line')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-03-25 14:37:00 +01:00
Joerg Roedel d05e4c8600 Merge branches 'iommu/fixes', 'arm/msm', 'arm/tegra', 'arm/mediatek', 'x86/vt-d', 'x86/amd', 'hyper-v' and 'core' into next 2019-03-01 11:24:51 +01:00
Bjorn Helgaas 780da9e4f5 iommu: Use dev_printk() when possible
Use dev_printk() when possible so the IOMMU messages are more consistent
with other messages related to the device.

E.g., I think these messages related to surprise hotplug:

  pciehp 0000:80:10.0:pcie004: Slot(36): Link Down
  iommu: Removing device 0000:87:00.0 from group 12
  pciehp 0000:80:10.0:pcie004: Slot(36): Card present
  pcieport 0000:80:10.0: Data Link Layer Link Active not set in 1000 msec

would be easier to read as these (also requires some PCI changes not
included here):

  pci 0000:80:10.0: Slot(36): Link Down
  pci 0000:87:00.0: Removing from iommu group 12
  pci 0000:80:10.0: Slot(36): Card present
  pci 0000:80:10.0: Data Link Layer Link Active not set in 1000 msec

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-02-11 12:02:14 +01:00
Dmitry Osipenko 1d7ae53b15 iommu: Introduce iotlb_sync_map callback
Introduce iotlb_sync_map() callback that is invoked in the end of
iommu_map(). This new callback allows IOMMU drivers to avoid syncing
after mapping of each contiguous chunk and sync only when the whole
mapping is completed, optimizing performance of the mapping operation.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-01-16 13:54:09 +01:00
Joerg Roedel dc9de8a2b2 iommu: Check for iommu_ops == NULL in iommu_probe_device()
This check needs to be there and got lost at some point
during development. Add it again.

Fixes: 641fb0efbf ('iommu/of: Don't call iommu_ops->add_device directly')
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reported-by: kernelci.org bot <bot@kernelci.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-12-20 10:02:20 +01:00
Joerg Roedel cc5aed44a3 iommu: Consolitate ->add/remove_device() calls
Put them into separate functions and call those where the
plain ops have been called before.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-12-17 12:47:50 +01:00
Joerg Roedel b4ef725eeb iommu: Introduce wrappers around dev->iommu_fwspec
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>
2018-12-17 10:38:30 +01:00
Paul Gortmaker c1af7b4013 iommu: Audit and remove any unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.
This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.

The advantage in removing such instances is that module.h itself
sources about 15 other headers; adding significantly to what we feed
cpp, and it can obscure what headers we are effectively using.

Since module.h might have been the implicit source for init.h
(for __init) and for export.h (for EXPORT_SYMBOL) we consider each
instance for the presence of either and replace as needed.

Cc: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-12-03 14:32:03 +01:00
Robin Murphy 5d95f40e62 iommu: Do physical merging in iommu_map_sg()
The original motivation for iommu_map_sg() was to give IOMMU drivers the
chance to map an IOVA-contiguous scatterlist as efficiently as they
could. It turns out that there isn't really much driver-specific
business involved there, so now that the default implementation is
mandatory let's just improve that - the main thing we're after is to use
larger pages wherever possible, and as long as domain->pgsize_bitmap
reflects reality, iommu_map() can already do that in a generic way. All
we need to do is detect physically-contiguous segments and batch them
into a single map operation, since whatever we do here is transparent to
our caller and not bound by any segment-length restrictions on the list
itself.

Speaking of efficiency, there's really very little point in duplicating
the checks that iommu_map() is going to do anyway, so those get cleared
up in the process.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-11-06 16:30:39 +01:00
Joerg Roedel 2f2fbfb71e Merge branches 'arm/renesas', 'arm/smmu', 'ppc/pamu', 'x86/vt-d', 'x86/amd' and 'core' into next 2018-10-10 18:09:37 +02:00
Zhen Lei 68a6efe86f iommu: Add "iommu.strict" command line option
Add a generic command line option to enable lazy unmapping via IOVA
flush queues, which will initally be suuported by iommu-dma. This echoes
the semantics of "intel_iommu=strict" (albeit with the opposite default
value), but in the driver-agnostic fashion of "iommu.passthrough".

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
[rm: move handling out of SMMUv3 driver, clean up documentation]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[will: dropped broken printk when parsing command-line option]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-10-01 13:01:32 +01:00
Rami Rosen 35449adce8 iommu: Fix a typo
This patch fixes a typo in iommu.c.

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-09-25 15:33:48 +02:00
Robin Murphy 701d8a624a iommu: Tidy up window attributes
The external interface to get/set window attributes is already
abstracted behind iommu_domain_{get,set}_attr(), so there's no real
reason for the internal interface to be different. Since we only have
one window-based driver anyway, clean up the core code by just moving
the DOMAIN_ATTR_WINDOWS handling directly into the PAMU driver.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-09-25 14:54:53 +02:00
Robin Murphy 6af588fed3 iommu: Add fast hook for getting DMA domains
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>
2018-09-25 10:23:16 +02:00
Nipun Gupta eab03e2a1a iommu/arm-smmu: Add support for the fsl-mc bus
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>
2018-09-25 09:47:53 +02:00
Christoph Hellwig d88e61faad iommu: Remove the ->map_sg indirection
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>
2018-08-08 11:06:20 +02:00
Olof Johansson 58d1131777 iommu: Add config option to set passthrough as default
This allows the default behavior to be controlled by a kernel config
option instead of changing the commandline for the kernel to include
"iommu.passthrough=on" or "iommu=pt" on machines where this is desired.

Likewise, for machines where this config option is enabled, it can be
disabled at boot time with "iommu.passthrough=off" or "iommu=nopt".

Also corrected iommu=pt documentation for IA-64, since it has no code that
parses iommu= at all.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-07-27 09:36:50 +02:00
Olof Johansson c52c72d3de iommu: Add sysfs attribyte for domain type
While we could print it at setup time, this is an easier way to match
each device to their default IOMMU allocation type.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-07-27 09:36:50 +02:00
Gary R Hook bad614b242 iommu: Enable debugfs exposure of IOMMU driver internals
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>
2018-07-06 14:06:30 +02:00
Lu Baolu 1eefe5a034 iommu: Clean up the comments for iommu_group_alloc
@name parameter has been removed.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-05-15 16:34:59 +02:00
Andy Shevchenko 7f9584df84 iommu: Remove extra NULL check when call strtobool()
strtobool() does check for NULL parameter already. No need to repeat.

While here, switch to kstrtobool() and unshadow actual error code
(which is still -EINVAL).

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2018-05-15 16:27:48 +02:00
Suravee Suthikulpanit c5611a8751 iommu: Do not return error code for APIs with size_t return type
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>
2018-02-13 19:31:20 +01:00
Jordan Crouse 9ae9df035c iommu: Check the result of iommu_group_get() for NULL
The result of iommu_group_get() was being blindly used in both
attach and detach which results in a dereference when trying
to work with an unknown device.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-12-20 09:48:36 -07:00
Joerg Roedel 47b59d8e40 Merge branches 'arm/exynos', 'arm/renesas', 'arm/rockchip', 'arm/omap', 'arm/mediatek', 'arm/tegra', 'arm/qcom', 'arm/smmu', 'ppc/pamu', 'x86/vt-d', 'x86/amd', 's390' and 'core' into next 2017-09-01 11:31:42 +02:00
Joerg Roedel add02cfdc9 iommu: Introduce Interface for IOMMU TLB Flushing
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>
2017-08-30 18:07:13 +02:00
Robin Murphy 1464d0b1de iommu: Avoid NULL group dereference
The recently-removed FIXME in iommu_get_domain_for_dev() turns out to
have been a little misleading, since that check is still worthwhile even
when groups *are* universal. We have a few IOMMU-aware drivers which
only care whether their device is already attached to an existing domain
or not, for which the previous behaviour of iommu_get_domain_for_dev()
was ideal, and who now crash if their device does not have an IOMMU.

With IOMMU groups now serving as a reliable indicator of whether a
device has an IOMMU or not (barring false-positives from VFIO no-IOMMU
mode), drivers could arguably do this:

	group = iommu_group_get(dev);
	if (group) {
		domain = iommu_get_domain_for_dev(dev);
		iommu_group_put(group);
	}

However, rather than duplicate that code across multiple callsites,
particularly when it's still only the domain they care about, let's skip
straight to the next step and factor out the check into the common place
it applies - in iommu_get_domain_for_dev() itself. Sure, it ends up
looking rather familiar, but now it's backed by the reasoning of having
a robust API able to do the expected thing for all devices regardless.

Fixes: 05f80300dc ("iommu: Finish making iommu_group support mandatory")
Reported-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-18 11:41:17 +02:00
Baoquan He e01d1913b0 iommu: Add is_attach_deferred call-back to iommu-ops
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>
2017-08-15 18:14:39 +02:00
Robin Murphy 05f80300dc iommu: Finish making iommu_group support mandatory
Now that all the drivers properly implementing the IOMMU API support
groups (I'm ignoring the etnaviv GPU MMUs which seemingly only do just
enough to convince the ARM DMA mapping ops), we can remove the FIXME
workarounds from the core code. In the process, it also seems logical to
make the .device_group callback non-optional for drivers calling
iommu_group_get_for_dev() - the current callers all implement it anyway,
and it doesn't make sense for any future callers not to either.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-08-10 00:03:51 +02:00
Joerg Roedel 72dcac6334 iommu: Warn once when device_group callback returns NULL
This callback should never return NULL. Print a warning if
that happens so that we notice and can fix it.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-06-28 13:29:46 +02:00