Commit Graph

302 Commits

Author SHA1 Message Date
Eric Auger 0659b8dc45 iommu/vt-d: Implement reserved region get/put callbacks
This patch registers the [FEE0_0000h - FEF0_000h] 1MB MSI
range as a reserved region and RMRR regions as direct regions.

This will allow to report those reserved regions in the
iommu-group sysfs.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-23 11:48:17 +00:00
Jacob Pan 65ca7f5f7d iommu/vt-d: Fix pasid table size encoding
Different encodings are used to represent supported PASID bits
and number of PASID table entries.
The current code assigns ecap_pss directly to extended context
table entry PTS which is wrong and could result in writing
non-zero bits to the reserved fields. IOMMU fault reason
11 will be reported when reserved bits are nonzero.
This patch converts ecap_pss to extend context entry pts encoding
based on VT-d spec. Chapter 9.4 as follows:
 - number of PASID bits = ecap_pss + 1
 - number of PASID table entries = 2^(pts + 5)
Software assigned limit of pasid_max value is also respected to
match the allocation limitation of PASID table.

cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Tested-by: Mika Kuoppala <mika.kuoppala@intel.com>
Fixes: 2f26e0a9c9 ('iommu/vt-d: Add basic SVM PASID support')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-01-04 15:18:57 +01:00
Xunlei Pang aec0e86172 iommu/vt-d: Flush old iommu caches for kdump when the device gets context mapped
We met the DMAR fault both on hpsa P420i and P421 SmartArray controllers
under kdump, it can be steadily reproduced on several different machines,
the dmesg log is like:
HP HPSA Driver (v 3.4.16-0)
hpsa 0000:02:00.0: using doorbell to reset controller
hpsa 0000:02:00.0: board ready after hard reset.
hpsa 0000:02:00.0: Waiting for controller to respond to no-op
DMAR: Setting identity map for device 0000:02:00.0 [0xe8000 - 0xe8fff]
DMAR: Setting identity map for device 0000:02:00.0 [0xf4000 - 0xf4fff]
DMAR: Setting identity map for device 0000:02:00.0 [0xbdf6e000 - 0xbdf6efff]
DMAR: Setting identity map for device 0000:02:00.0 [0xbdf6f000 - 0xbdf7efff]
DMAR: Setting identity map for device 0000:02:00.0 [0xbdf7f000 - 0xbdf82fff]
DMAR: Setting identity map for device 0000:02:00.0 [0xbdf83000 - 0xbdf84fff]
DMAR: DRHD: handling fault status reg 2
DMAR: [DMA Read] Request device [02:00.0] fault addr fffff000 [fault reason 06] PTE Read access is not set
hpsa 0000:02:00.0: controller message 03:00 timed out
hpsa 0000:02:00.0: no-op failed; re-trying

After some debugging, we found that the fault addr is from DMA initiated at
the driver probe stage after reset(not in-flight DMA), and the corresponding
pte entry value is correct, the fault is likely due to the old iommu caches
of the in-flight DMA before it.

Thus we need to flush the old cache after context mapping is setup for the
device, where the device is supposed to finish reset at its driver probe
stage and no in-flight DMA exists hereafter.

I'm not sure if the hardware is responsible for invalidating all the related
caches allocated in the iommu hardware before, but seems not the case for hpsa,
actually many device drivers have problems in properly resetting the hardware.
Anyway flushing (again) by software in kdump kernel when the device gets context
mapped which is a quite infrequent operation does little harm.

With this patch, the problematic machine can survive the kdump tests.

CC: Myron Stowe <myron.stowe@gmail.com>
CC: Joseph Szczypek <jszczype@redhat.com>
CC: Don Brace <don.brace@microsemi.com>
CC: Baoquan He <bhe@redhat.com>
CC: Dave Young <dyoung@redhat.com>
Fixes: 091d42e43d ("iommu/vt-d: Copy translation tables from old kernel")
Fixes: dbcd861f25 ("iommu/vt-d: Do not re-use domain-ids from the old kernel")
Fixes: cf484d0e69 ("iommu/vt-d: Mark copied context entries")
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Tested-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2017-01-04 15:14:04 +01:00
Linus Torvalds e71c3978d6 Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull smp hotplug updates from Thomas Gleixner:
 "This is the final round of converting the notifier mess to the state
  machine. The removal of the notifiers and the related infrastructure
  will happen around rc1, as there are conversions outstanding in other
  trees.

  The whole exercise removed about 2000 lines of code in total and in
  course of the conversion several dozen bugs got fixed. The new
  mechanism allows to test almost every hotplug step standalone, so
  usage sites can exercise all transitions extensively.

  There is more room for improvement, like integrating all the
  pointlessly different architecture mechanisms of synchronizing,
  setting cpus online etc into the core code"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
  tracing/rb: Init the CPU mask on allocation
  soc/fsl/qbman: Convert to hotplug state machine
  soc/fsl/qbman: Convert to hotplug state machine
  zram: Convert to hotplug state machine
  KVM/PPC/Book3S HV: Convert to hotplug state machine
  arm64/cpuinfo: Convert to hotplug state machine
  arm64/cpuinfo: Make hotplug notifier symmetric
  mm/compaction: Convert to hotplug state machine
  iommu/vt-d: Convert to hotplug state machine
  mm/zswap: Convert pool to hotplug state machine
  mm/zswap: Convert dst-mem to hotplug state machine
  mm/zsmalloc: Convert to hotplug state machine
  mm/vmstat: Convert to hotplug state machine
  mm/vmstat: Avoid on each online CPU loops
  mm/vmstat: Drop get_online_cpus() from init_cpu_node_state/vmstat_cpu_dead()
  tracing/rb: Convert to hotplug state machine
  oprofile/nmi timer: Convert to hotplug state machine
  net/iucv: Use explicit clean up labels in iucv_init()
  x86/pci/amd-bus: Convert to hotplug state machine
  x86/oprofile/nmi: Convert to hotplug state machine
  ...
2016-12-12 19:25:04 -08:00
Anna-Maria Gleixner 21647615db iommu/vt-d: Convert to hotplug state machine
Install the callbacks via the state machine.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org
Cc: rt@linutronix.de
Cc: David Woodhouse <dwmw2@infradead.org>
Link: http://lkml.kernel.org/r/20161126231350.10321-14-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-02 00:52:37 +01:00
Linus Torvalds 105ecadc6d Merge git://git.infradead.org/intel-iommu
Pull IOMMU fixes from David Woodhouse:
 "Two minor fixes.

  The first fixes the assignment of SR-IOV virtual functions to the
  correct IOMMU unit, and the second fixes the excessively large (and
  physically contiguous) PASID tables used with SVM"

* git://git.infradead.org/intel-iommu:
  iommu/vt-d: Fix PASID table allocation
  iommu/vt-d: Fix IOMMU lookup for SR-IOV Virtual Functions
2016-11-27 08:24:46 -08:00
Joerg Roedel bea64033dd iommu/vt-d: Fix dead-locks in disable_dmar_iommu() path
It turns out that the disable_dmar_iommu() code-path tried
to get the device_domain_lock recursivly, which will
dead-lock when this code runs on dmar removal. Fix both
code-paths that could lead to the dead-lock.

Fixes: 55d940430a ('iommu/vt-d: Get rid of domain->iommu_lock')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-11-08 15:08:26 +01:00
Ashok Raj 1c387188c6 iommu/vt-d: Fix IOMMU lookup for SR-IOV Virtual Functions
The VT-d specification (§8.3.3) says:
    ‘Virtual Functions’ of a ‘Physical Function’ are under the scope
    of the same remapping unit as the ‘Physical Function’.

The BIOS is not required to list all the possible VFs in the scope
tables, and arguably *shouldn't* make any attempt to do so, since there
could be a huge number of them.

This has been broken basically for ever — the VF is never going to match
against a specific unit's scope, so it ends up being assigned to the
INCLUDE_ALL IOMMU. Which was always actually correct by coincidence, but
now we're looking at Root-Complex integrated devices with SR-IOV support
it's going to start being wrong.

Fix it to simply use pci_physfn() before doing the lookup for PCI devices.

Cc: stable@vger.kernel.org
Signed-off-by: Sainath Grandhi <sainath.grandhi@intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2016-10-30 05:32:51 -06:00
Joerg Roedel 1c5ebba95b iommu/vt-d: Make sure RMRRs are mapped before domain goes public
When a domain is allocated through the get_valid_domain_for_dev
path, it will be context-mapped before the RMRR regions are
mapped in the page-table. This opens a short time window
where device-accesses to these regions fail and causing DMAR
faults.

Fix this by mapping the RMRR regions before the domain is
context-mapped.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-09-05 13:00:28 +02:00
Joerg Roedel 76208356a0 iommu/vt-d: Split up get_domain_for_dev function
Split out the search for an already existing domain and the
context mapping of the device to the new domain.

This allows to map possible RMRR regions into the domain
before it is context mapped.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-09-05 13:00:28 +02:00
Krzysztof Kozlowski 00085f1efa dma-mapping: use unsigned long for dma_attrs
The dma-mapping core and the implementations do not change the DMA
attributes passed by pointer.  Thus the pointer can point to const data.
However the attributes do not have to be a bitfield.  Instead unsigned
long will do fine:

1. This is just simpler.  Both in terms of reading the code and setting
   attributes.  Instead of initializing local attributes on the stack
   and passing pointer to it to dma_set_attr(), just set the bits.

2. It brings safeness and checking for const correctness because the
   attributes are passed by value.

Semantic patches for this change (at least most of them):

    virtual patch
    virtual context

    @r@
    identifier f, attrs;

    @@
    f(...,
    - struct dma_attrs *attrs
    + unsigned long attrs
    , ...)
    {
    ...
    }

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

and

    // Options: --all-includes
    virtual patch
    virtual context

    @r@
    identifier f, attrs;
    type t;

    @@
    t f(..., struct dma_attrs *attrs);

    @@
    identifier r.f;
    @@
    f(...,
    - NULL
    + 0
     )

Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Acked-by: Mark Salter <msalter@redhat.com> [c6x]
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> [cris]
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> [drm]
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Fabien Dessenne <fabien.dessenne@st.com> [bdisp]
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> [vb2-core]
Acked-by: David Vrabel <david.vrabel@citrix.com> [xen]
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [xen swiotlb]
Acked-by: Joerg Roedel <jroedel@suse.de> [iommu]
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [s390]
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no> [avr32]
Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc]
Acked-by: Robin Murphy <robin.murphy@arm.com> [arm64 and dma-iommu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-04 08:50:07 -04:00
Linus Torvalds dd9671172a IOMMU Updates for Linux v4.8
In the updates:
 
 	* Big endian support and preparation for defered probing for the
 	  Exynos IOMMU driver
 
 	* Simplifications in iommu-group id handling
 
 	* Support for Mediatek generation one IOMMU hardware
 
 	* Conversion of the AMD IOMMU driver to use the generic IOVA
 	  allocator. This driver now also benefits from the recent
 	  scalability improvements in the IOVA code.
 
 	* Preparations to use generic DMA mapping code in the Rockchip
 	  IOMMU driver
 
 	* Device tree adaption and conversion to use generic page-table
 	  code for the MSM IOMMU driver
 
 	* An iova_to_phys optimization in the ARM-SMMU driver to greatly
 	  improve page-table teardown performance with VFIO
 
 	* Various other small fixes and conversions
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Merge tag 'iommu-updates-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull IOMMU updates from Joerg Roedel:

 - big-endian support and preparation for defered probing for the Exynos
   IOMMU driver

 - simplifications in iommu-group id handling

 - support for Mediatek generation one IOMMU hardware

 - conversion of the AMD IOMMU driver to use the generic IOVA allocator.
   This driver now also benefits from the recent scalability
   improvements in the IOVA code.

 - preparations to use generic DMA mapping code in the Rockchip IOMMU
   driver

 - device tree adaption and conversion to use generic page-table code
   for the MSM IOMMU driver

 - an iova_to_phys optimization in the ARM-SMMU driver to greatly
   improve page-table teardown performance with VFIO

 - various other small fixes and conversions

* tag 'iommu-updates-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (59 commits)
  iommu/amd: Initialize dma-ops domains with 3-level page-table
  iommu/amd: Update Alias-DTE in update_device_table()
  iommu/vt-d: Return error code in domain_context_mapping_one()
  iommu/amd: Use container_of to get dma_ops_domain
  iommu/amd: Flush iova queue before releasing dma_ops_domain
  iommu/amd: Handle IOMMU_DOMAIN_DMA in ops->domain_free call-back
  iommu/amd: Use dev_data->domain in get_domain()
  iommu/amd: Optimize map_sg and unmap_sg
  iommu/amd: Introduce dir2prot() helper
  iommu/amd: Implement timeout to flush unmap queues
  iommu/amd: Implement flush queue
  iommu/amd: Allow NULL pointer parameter for domain_flush_complete()
  iommu/amd: Set up data structures for flush queue
  iommu/amd: Remove align-parameter from __map_single()
  iommu/amd: Remove other remains of old address allocator
  iommu/amd: Make use of the generic IOVA allocator
  iommu/amd: Remove special mapping code for dma_ops path
  iommu/amd: Pass gfp-flags to iommu_map_page()
  iommu/amd: Implement apply_dm_region call-back
  iommu/amd: Create a list of reserved iova addresses
  ...
2016-08-01 07:25:10 -04:00
Linus Torvalds 194dc870a5 Add braces to avoid "ambiguous ‘else’" compiler warnings
Some of our "for_each_xyz()" macro constructs make gcc unhappy about
lack of braces around if-statements inside or outside the loop, because
the loop construct itself has a "if-then-else" statement inside of it.

The resulting warnings look something like this:

  drivers/gpu/drm/i915/i915_debugfs.c: In function ‘i915_dump_lrc’:
  drivers/gpu/drm/i915/i915_debugfs.c:2103:6: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses]
     if (ctx != dev_priv->kernel_context)
        ^

even if the code itself is fine.

Since the warning is fairly easy to avoid by adding a braces around the
if-statement near the for_each_xyz() construct, do so, rather than
disabling the otherwise potentially useful warning.

(The if-then-else statements used in the "for_each_xyz()" constructs are
designed to be inherently safe even with no braces, but in this case
it's quite understandable that gcc isn't really able to tell that).

This finally leaves the standard "allmodconfig" build with just a
handful of remaining warnings, so new and valid warnings hopefully will
stand out.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-27 20:03:31 -07:00
Joerg Roedel f360d3241f Merge branches 'x86/amd', 'x86/vt-d', 'arm/exynos', 'arm/mediatek', 'arm/msm', 'arm/rockchip', 'arm/smmu' and 'core' into next 2016-07-26 16:02:37 +02:00
Wei Yang 5c365d18a7 iommu/vt-d: Return error code in domain_context_mapping_one()
In 'commit <55d940430ab9> ("iommu/vt-d: Get rid of domain->iommu_lock")',
the error handling path is changed a little, which makes the function
always return 0.

This path fixes this.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Fixes: 55d940430a ('iommu/vt-d: Get rid of domain->iommu_lock')
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-07-14 10:26:30 +02:00
Aaron Campbell 0caa7616a6 iommu/vt-d: Fix infinite loop in free_all_cpu_cached_iovas
Per VT-d spec Section 10.4.2 ("Capability Register"), the maximum
number of possible domains is 64K; indeed this is the maximum value
that the cap_ndoms() macro will expand to.  Since the value 65536
will not fix in a u16, the 'did' variable must be promoted to an
int, otherwise the test for < 65536 will always be true and the
loop will never end.

The symptom, in my case, was a hung machine during suspend.

Fixes: 3bd4f9112f ("iommu/vt-d: Fix overflow of iommu->domains array")
Signed-off-by: Aaron Campbell <aaron@monkey.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-07-04 13:34:52 +02:00
Jan Niehusmann 3bd4f9112f iommu/vt-d: Fix overflow of iommu->domains array
The valid range of 'did' in get_iommu_domain(*iommu, did)
is 0..cap_ndoms(iommu->cap), so don't exceed that
range in free_all_cpu_cached_iovas().

The user-visible impact of the out-of-bounds access is the machine
hanging on suspend-to-ram. It is, in fact, a kernel panic, but due
to already suspended devices, that's often not visible to the user.

Fixes: 22e2f9fa63 ("iommu/vt-d: Use per-cpu IOVA caching")
Signed-off-by: Jan Niehusmann <jan@gondor.com>
Tested-By: Marius Vlad <marius.c.vlad@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-06-27 13:21:37 +02:00
Joerg Roedel a4c34ff1c0 iommu/vt-d: Enable QI on all IOMMUs before setting root entry
This seems to be required on some X58 chipsets on systems
with more than one IOMMU. QI does not work until it is
enabled on all IOMMUs in the system.

Reported-by: Dheeraj CVR <cvr.dheeraj@gmail.com>
Tested-by: Dheeraj CVR <cvr.dheeraj@gmail.com>
Fixes: 5f0a7f7614 ('iommu/vt-d: Make root entry visible for hardware right after allocation')
Cc: stable@vger.kernel.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-06-17 11:29:48 +02:00
Wei Yang 86f004c77c iommu/vt-d: Reduce extra first level entry in iommu->domains
In commit <8bf478163e69> ("iommu/vt-d: Split up iommu->domains array"), it
it splits iommu->domains in two levels. Each first level contains 256
entries of second level. In case of the ndomains is exact a multiple of
256, it would have one more extra first level entry for current
implementation.

This patch refines this calculation to reduce the extra first level entry.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-06-15 13:36:58 +02:00
Linus Torvalds 2566278551 Merge git://git.infradead.org/intel-iommu
Pull intel IOMMU updates from David Woodhouse:
 "This patchset improves the scalability of the Intel IOMMU code by
  resolving two spinlock bottlenecks and eliminating the linearity of
  the IOVA allocator, yielding up to ~5x performance improvement and
  approaching 'iommu=off' performance"

* git://git.infradead.org/intel-iommu:
  iommu/vt-d: Use per-cpu IOVA caching
  iommu/iova: introduce per-cpu caching to iova allocation
  iommu/vt-d: change intel-iommu to use IOVA frame numbers
  iommu/vt-d: avoid dev iotlb logic for domains with no dev iotlbs
  iommu/vt-d: only unmap mapped entries
  iommu/vt-d: correct flush_unmaps pfn usage
  iommu/vt-d: per-cpu deferred invalidation queues
  iommu/vt-d: refactoring of deferred flush entries
2016-05-27 13:49:24 -07:00
Joerg Roedel 6c0b43df74 Merge branches 'arm/io-pgtable', 'arm/rockchip', 'arm/omap', 'x86/vt-d', 'ppc/pamu', 'core' and 'x86/amd' into next 2016-05-09 19:39:17 +02:00
Omer Peleg 22e2f9fa63 iommu/vt-d: Use per-cpu IOVA caching
Commit 9257b4a2 ('iommu/iova: introduce per-cpu caching to iova allocation')
introduced per-CPU IOVA caches to massively improve scalability. Use them.

Signed-off-by: Omer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased, cleaned up and reworded the commit message]
Signed-off-by: Adam Morrison <mad@cs.technion.ac.il>
Reviewed-by: Shaohua Li <shli@fb.com>
Reviewed-by: Ben Serebrin <serebrin@google.com>
[dwmw2: split out VT-d part into a separate patch]
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2016-04-20 15:44:48 -04:00
Omer Peleg 2aac630429 iommu/vt-d: change intel-iommu to use IOVA frame numbers
Make intel-iommu map/unmap/invalidate work with IOVA pfns instead of
pointers to "struct iova". This avoids using the iova struct from the IOVA
red-black tree and the resulting explicit find_iova() on unmap.

This patch will allow us to cache IOVAs in the next patch, in order to
avoid rbtree operations for the majority of map/unmap operations.

Note: In eliminating the find_iova() operation, we have also eliminated
the sanity check previously done in the unmap flow. Arguably, this was
overhead that is better avoided in production code, but it could be
brought back as a debug option for driver development.

Signed-off-by: Omer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased, fixed to not break iova api, and reworded
 the commit message]
Signed-off-by: Adam Morrison <mad@cs.technion.ac.il>
Reviewed-by: Shaohua Li <shli@fb.com>
Reviewed-by: Ben Serebrin <serebrin@google.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2016-04-20 15:07:22 -04:00
Omer Peleg 0824c5920b iommu/vt-d: avoid dev iotlb logic for domains with no dev iotlbs
This patch avoids taking the device_domain_lock in iommu_flush_dev_iotlb()
for domains with no dev iotlb devices.

Signed-off-by: Omer Peleg <omer@cs.technion.ac.il>
[gvdl@google.com: fixed locking issues]
Signed-off-by: Godfrey van der Linden <gvdl@google.com>
[mad@cs.technion.ac.il: rebased and reworded the commit message]
Signed-off-by: Adam Morrison <mad@cs.technion.ac.il>
Reviewed-by: Shaohua Li <shli@fb.com>
Reviewed-by: Ben Serebrin <serebrin@google.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2016-04-20 15:06:15 -04:00
Omer Peleg 769530e4ba iommu/vt-d: only unmap mapped entries
Current unmap implementation unmaps the entire area covered by the IOVA
range, which is a power-of-2 aligned region. The corresponding map,
however, only maps those pages originally mapped by the user. This
discrepancy can lead to unmapping of already unmapped entries, which is
unneeded work.

With this patch, only mapped pages are unmapped. This is also a baseline
for a map/unmap implementation based on IOVAs and not iova structures,
which will allow caching.

Signed-off-by: Omer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased and reworded the commit message]
Signed-off-by: Adam Morrison <mad@cs.technion.ac.il>
Reviewed-by: Shaohua Li <shli@fb.com>
Reviewed-by: Ben Serebrin <serebrin@google.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2016-04-20 15:06:01 -04:00
Omer Peleg f5c0c08b1e iommu/vt-d: correct flush_unmaps pfn usage
Change flush_unmaps() to correctly pass iommu_flush_iotlb_psi()
dma addresses.  (x86_64 mm and dma have the same size for pages
at the moment, but this usage improves consistency.)

Signed-off-by: Omer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased and reworded the commit message]
Signed-off-by: Adam Morrison <mad@cs.technion.ac.il>
Reviewed-by: Shaohua Li <shli@fb.com>
Reviewed-by: Ben Serebrin <serebrin@google.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2016-04-20 15:05:56 -04:00
Omer Peleg aa4732406e iommu/vt-d: per-cpu deferred invalidation queues
The IOMMU's IOTLB invalidation is a costly process.  When iommu mode
is not set to "strict", it is done asynchronously. Current code
amortizes the cost of invalidating IOTLB entries by batching all the
invalidations in the system and performing a single global invalidation
instead. The code queues pending invalidations in a global queue that
is accessed under the global "async_umap_flush_lock" spinlock, which
can result is significant spinlock contention.

This patch splits this deferred queue into multiple per-cpu deferred
queues, and thus gets rid of the "async_umap_flush_lock" and its
contention.  To keep existing deferred invalidation behavior, it still
invalidates the pending invalidations of all CPUs whenever a CPU
reaches its watermark or a timeout occurs.

Signed-off-by: Omer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased, cleaned up and reworded the commit message]
Signed-off-by: Adam Morrison <mad@cs.technion.ac.il>
Reviewed-by: Shaohua Li <shli@fb.com>
Reviewed-by: Ben Serebrin <serebrin@google.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2016-04-20 15:05:24 -04:00
Omer Peleg 314f1dc140 iommu/vt-d: refactoring of deferred flush entries
Currently, deferred flushes' info is striped between several lists in
the flush tables. Instead, move all information about a specific flush
to a single entry in this table.

This patch does not introduce any functional change.

Signed-off-by: Omer Peleg <omer@cs.technion.ac.il>
[mad@cs.technion.ac.il: rebased and reworded the commit message]
Signed-off-by: Adam Morrison <mad@cs.technion.ac.il>
Reviewed-by: Shaohua Li <shli@fb.com>
Reviewed-by: Ben Serebrin <serebrin@google.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2016-04-20 15:05:20 -04:00
Dan Carpenter 0b74ecdfbe iommu/vt-d: Silence an uninitialized variable warning
My static checker complains that "dma_alias" is uninitialized unless we
are dealing with a pci device.  This is true but harmless.  Anyway, we
can flip the condition around to silence the warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-04-07 14:51:47 +02:00
Michael S. Tsirkin 3d1a2442d2 x86/vt-d: Fix comment for dma_pte_free_pagetable()
dma_pte_free_pagetable no longer depends on last level ptes
being clear, it clears them itself.  Fix up the comment to
match.

Cc: Jiang Liu <jiang.liu@linux.intel.com>
Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-04-05 17:00:37 +02:00
Joerg Roedel e6a8c9b337 iommu/vt-d: Use BUS_NOTIFY_REMOVED_DEVICE in hotplug path
In the PCI hotplug path of the Intel IOMMU driver, replace
the usage of the BUS_NOTIFY_DEL_DEVICE notifier, which is
executed before the driver is unbound from the device, with
BUS_NOTIFY_REMOVED_DEVICE, which runs after that.

This fixes a kernel BUG being triggered in the VT-d code
when the device driver tries to unmap DMA buffers and the
VT-d driver already destroyed all mappings.

Reported-by: Stefani Seibold <stefani@seibold.net>
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-02-29 23:55:16 +01:00
Jeremy McNicoll da972fb13b iommu/vt-d: Don't skip PCI devices when disabling IOTLB
Fix a simple typo when disabling IOTLB on PCI(e) devices.

Fixes: b16d0cb9e2 ("iommu/vt-d: Always enable PASID/PRI PCI capabilities before ATS")
Cc: stable@vger.kernel.org  # v4.4
Signed-off-by: Jeremy McNicoll <jmcnicol@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-01-29 12:18:13 +01:00
Dan Williams 3e6110fd54 Revert "scatterlist: use sg_phys()"
commit db0fa0cb01 "scatterlist: use sg_phys()" did replacements of
the form:

    phys_addr_t phys = page_to_phys(sg_page(s));
    phys_addr_t phys = sg_phys(s) & PAGE_MASK;

However, this breaks platforms where sizeof(phys_addr_t) >
sizeof(unsigned long).  Revert for 4.3 and 4.4 to make room for a
combined helper in 4.5.

Cc: <stable@vger.kernel.org>
Cc: Jens Axboe <axboe@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Fixes: db0fa0cb01 ("scatterlist: use sg_phys()")
Suggested-by: Joerg Roedel <joro@8bytes.org>
Reported-by: Vitaly Lavrov <vel21ripn@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-12-15 12:54:06 -08:00
Mel Gorman d0164adc89 mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd
__GFP_WAIT has been used to identify atomic context in callers that hold
spinlocks or are in interrupts.  They are expected to be high priority and
have access one of two watermarks lower than "min" which can be referred
to as the "atomic reserve".  __GFP_HIGH users get access to the first
lower watermark and can be called the "high priority reserve".

Over time, callers had a requirement to not block when fallback options
were available.  Some have abused __GFP_WAIT leading to a situation where
an optimisitic allocation with a fallback option can access atomic
reserves.

This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
cannot sleep and have no alternative.  High priority users continue to use
__GFP_HIGH.  __GFP_DIRECT_RECLAIM identifies callers that can sleep and
are willing to enter direct reclaim.  __GFP_KSWAPD_RECLAIM to identify
callers that want to wake kswapd for background reclaim.  __GFP_WAIT is
redefined as a caller that is willing to enter direct reclaim and wake
kswapd for background reclaim.

This patch then converts a number of sites

o __GFP_ATOMIC is used by callers that are high priority and have memory
  pools for those requests. GFP_ATOMIC uses this flag.

o Callers that have a limited mempool to guarantee forward progress clear
  __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
  into this category where kswapd will still be woken but atomic reserves
  are not used as there is a one-entry mempool to guarantee progress.

o Callers that are checking if they are non-blocking should use the
  helper gfpflags_allow_blocking() where possible. This is because
  checking for __GFP_WAIT as was done historically now can trigger false
  positives. Some exceptions like dm-crypt.c exist where the code intent
  is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
  flag manipulations.

o Callers that built their own GFP flags instead of starting with GFP_KERNEL
  and friends now also need to specify __GFP_KSWAPD_RECLAIM.

The first key hazard to watch out for is callers that removed __GFP_WAIT
and was depending on access to atomic reserves for inconspicuous reasons.
In some cases it may be appropriate for them to use __GFP_HIGH.

The second key hazard is callers that assembled their own combination of
GFP flags instead of starting with something like GFP_KERNEL.  They may
now wish to specify __GFP_KSWAPD_RECLAIM.  It's almost certainly harmless
if it's missed in most cases as other activity will wake kswapd.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Linus Torvalds 39cf7c3981 IOMMU Updates for Linux v4.4
This time including:
 
 	* A new IOMMU driver for s390 pci devices
 
 	* Common dma-ops support based on iommu-api for ARM64. The plan is to
 	  use this as a basis for ARM32 and hopefully other architectures as
 	  well in the future.
 
 	* MSI support for ARM-SMMUv3
 
 	* Cleanups and dead code removal in the AMD IOMMU driver
 
 	* Better RMRR handling for the Intel VT-d driver
 
 	* Various other cleanups and small fixes
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Merge tag 'iommu-updates-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu updates from Joerg Roedel:
 "This time including:

   - A new IOMMU driver for s390 pci devices

   - Common dma-ops support based on iommu-api for ARM64.  The plan is
     to use this as a basis for ARM32 and hopefully other architectures
     as well in the future.

   - MSI support for ARM-SMMUv3

   - Cleanups and dead code removal in the AMD IOMMU driver

   - Better RMRR handling for the Intel VT-d driver

   - Various other cleanups and small fixes"

* tag 'iommu-updates-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (41 commits)
  iommu/vt-d: Fix return value check of parse_ioapics_under_ir()
  iommu/vt-d: Propagate error-value from ir_parse_ioapic_hpet_scope()
  iommu/vt-d: Adjust the return value of the parse_ioapics_under_ir
  iommu: Move default domain allocation to iommu_group_get_for_dev()
  iommu: Remove is_pci_dev() fall-back from iommu_group_get_for_dev
  iommu/arm-smmu: Switch to device_group call-back
  iommu/fsl: Convert to device_group call-back
  iommu: Add device_group call-back to x86 iommu drivers
  iommu: Add generic_device_group() function
  iommu: Export and rename iommu_group_get_for_pci_dev()
  iommu: Revive device_group iommu-ops call-back
  iommu/amd: Remove find_last_devid_on_pci()
  iommu/amd: Remove first/last_device handling
  iommu/amd: Initialize amd_iommu_last_bdf for DEV_ALL
  iommu/amd: Cleanup buffer allocation
  iommu/amd: Remove cmd_buf_size and evt_buf_size from struct amd_iommu
  iommu/amd: Align DTE flag definitions
  iommu/amd: Remove old alias handling code
  iommu/amd: Set alias DTE in do_attach/do_detach
  iommu/amd: WARN when __[attach|detach]_device are called with irqs enabled
  ...
2015-11-05 16:12:10 -08:00
Linus Torvalds ab1228e42e Merge git://git.infradead.org/intel-iommu
Pull intel iommu updates from David Woodhouse:
 "This adds "Shared Virtual Memory" (aka PASID support) for the Intel
  IOMMU.  This allows devices to do DMA using process address space,
  translated through the normal CPU page tables for the relevant mm.

  With corresponding support added to the i915 driver, this has been
  tested with the graphics device on Skylake.  We don't have the
  required TLP support in our PCIe root ports for supporting discrete
  devices yet, so it's only integrated devices that can do it so far"

* git://git.infradead.org/intel-iommu: (23 commits)
  iommu/vt-d: Fix rwxp flags in SVM device fault callback
  iommu/vt-d: Expose struct svm_dev_ops without CONFIG_INTEL_IOMMU_SVM
  iommu/vt-d: Clean up pasid_enabled() and ecs_enabled() dependencies
  iommu/vt-d: Handle Caching Mode implementations of SVM
  iommu/vt-d: Fix SVM IOTLB flush handling
  iommu/vt-d: Use dev_err(..) in intel_svm_device_to_iommu(..)
  iommu/vt-d: fix a loop in prq_event_thread()
  iommu/vt-d: Fix IOTLB flushing for global pages
  iommu/vt-d: Fix address shifting in page request handler
  iommu/vt-d: shift wrapping bug in prq_event_thread()
  iommu/vt-d: Fix NULL pointer dereference in page request error case
  iommu/vt-d: Implement SVM_FLAG_SUPERVISOR_MODE for kernel access
  iommu/vt-d: Implement SVM_FLAG_PRIVATE_PASID to allocate unique PASIDs
  iommu/vt-d: Add callback to device driver on page faults
  iommu/vt-d: Implement page request handling
  iommu/vt-d: Generalise DMAR MSI setup to allow for page request events
  iommu/vt-d: Implement deferred invalidate for SVM
  iommu/vt-d: Add basic SVM PASID support
  iommu/vt-d: Always enable PASID/PRI PCI capabilities before ATS
  iommu/vt-d: Add initial support for PASID tables
  ...
2015-11-05 16:06:52 -08:00
Joerg Roedel b67ad2f7c7 Merge branches 'x86/vt-d', 'arm/omap', 'arm/smmu', 's390', 'core' and 'x86/amd' into next
Conflicts:
	drivers/iommu/amd_iommu_types.h
2015-11-02 20:03:34 +09:00
David Woodhouse d42fde7084 iommu/vt-d: Clean up pasid_enabled() and ecs_enabled() dependencies
When booted with intel_iommu=ecs_off we were still allocating the PASID
tables even though we couldn't actually use them. We really want to make
the pasid_enabled() macro depend on ecs_enabled().

Which is unfortunate, because currently they're the other way round to
cope with the Broadwell/Skylake problems with ECS.

Instead of having ecs_enabled() depend on pasid_enabled(), which was never
something that made me happy anyway, make it depend in the normal case
on the "broken PASID" bit 28 *not* being set.

Then pasid_enabled() can depend on ecs_enabled() as it should. And we also
don't need to mess with it if we ever see an implementation that has some
features requiring ECS (like PRI) but which *doesn't* have PASID support.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-24 21:33:01 +02:00
Joerg Roedel a960fadbe6 iommu: Add device_group call-back to x86 iommu drivers
Set the device_group call-back to pci_device_group() for the
Intel VT-d and the AMD IOMMU driver.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-22 00:00:49 +02:00
Linus Torvalds 8a70dd2669 Merge tag 'for-linus-20151021' of git://git.infradead.org/intel-iommu
Pull intel-iommu bugfix from David Woodhouse:
 "This contains a single fix, for when the IOMMU API is used to overlay
  an existing mapping comprised of 4KiB pages, with a mapping that can
  use superpages.

  For the *first* superpage in the new mapping, we were correctly¹
  freeing the old bottom-level page table page and clearing the link to
  it, before installing the superpage.  For subsequent superpages,
  however, we weren't.  This causes a memory leak, and a warning about
  setting a PTE which is already set.

  ¹ Well, not *entirely* correctly.  We just free the page table pages
    right there and then, which is wrong.  In fact they should only be
    freed *after* the IOTLB is flushed so we know the hardware will no
    longer be looking at them....  and in fact I note that the IOTLB
    flush is completely missing from the intel_iommu_map() code path,
    although it needs to be there if it's permitted to overwrite
    existing mappings.

    Fixing those is somewhat more intrusive though, and will probably
    need to wait for 4.4 at this point"

* tag 'for-linus-20151021' of git://git.infradead.org/intel-iommu:
  iommu/vt-d: fix range computation when making room for large pages
2015-10-22 06:32:48 +09:00
Sudeep Dutt b9997e385e iommu/vt-d: Use dev_err(..) in intel_svm_device_to_iommu(..)
This will give a little bit of assistance to those developing drivers
using SVM. It might cause a slight annoyance to end-users whose kernel
disables the IOMMU when drivers are trying to use it. But the fix there
is to fix the kernel to enable the IOMMU.

Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-19 15:03:00 +01:00
David Woodhouse a222a7f0bb iommu/vt-d: Implement page request handling
Largely based on the driver-mode implementation by Jesse Barnes.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 15:35:19 +01:00
David Woodhouse 907fea3491 iommu/vt-d: Implement deferred invalidate for SVM
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 13:22:35 +01:00
David Woodhouse 2f26e0a9c9 iommu/vt-d: Add basic SVM PASID support
This provides basic PASID support for endpoint devices, tested with a
version of the i915 driver.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 12:55:45 +01:00
David Woodhouse b16d0cb9e2 iommu/vt-d: Always enable PASID/PRI PCI capabilities before ATS
The behaviour if you enable PASID support after ATS is undefined. So we
have to enable it first, even if we don't know whether we'll need it.

This is safe enough; unless we set up a context that permits it, the device
can't actually *do* anything with it.

Also shift the feature detction to dmar_insert_one_dev_info() as it only
needs to happen once.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 12:05:39 +01:00
David Woodhouse 8a94ade4ce iommu/vt-d: Add initial support for PASID tables
Add CONFIG_INTEL_IOMMU_SVM, and allocate PASID tables on supported hardware.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 11:24:51 +01:00
David Woodhouse ae853ddb9a iommu/vt-d: Introduce intel_iommu=pasid28, and pasid_enabled() macro
As long as we use an identity mapping to work around the worst of the
hardware bugs which caused us to defeature it and change the definition
of the capability bit, we *can* use PASID support on the devices which
advertised it in bit 28 of the Extended Capability Register.

Allow people to do so with 'intel_iommu=pasid28' on the command line.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 11:24:45 +01:00
David Woodhouse d14053b3c7 iommu/vt-d: Fix ATSR handling for Root-Complex integrated endpoints
The VT-d specification says that "Software must enable ATS on endpoint
devices behind a Root Port only if the Root Port is reported as
supporting ATS transactions."

We walk up the tree to find a Root Port, but for integrated devices we
don't find one — we get to the host bridge. In that case we *should*
allow ATS. Currently we don't, which means that we are incorrectly
failing to use ATS for the integrated graphics. Fix that.

We should never break out of this loop "naturally" with bus==NULL,
since we'll always find bridge==NULL in that case (and now return 1).

So remove the check for (!bridge) after the loop, since it can never
happen. If it did, it would be worthy of a BUG_ON(!bridge). But since
it'll oops anyway in that case, that'll do just as well.

Cc: stable@vger.kernel.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 09:28:56 +01:00
Dan Williams dfddb969ed iommu/vt-d: Switch from ioremap_cache to memremap
In preparation for deprecating ioremap_cache() convert its usage in
intel-iommu to memremap.  This also eliminates the mishandling of the
__iomem annotation in the implementation.

Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-14 15:22:06 +02:00
Christian Zander ba2374fd2b iommu/vt-d: fix range computation when making room for large pages
In preparation for the installation of a large page, any small page
tables that may still exist in the target IOV address range are
removed.  However, if a scatter/gather list entry is large enough to
fit more than one large page, the address space for any subsequent
large pages is not cleared of conflicting small page tables.

This can cause legitimate mapping requests to fail with errors of the
form below, potentially followed by a series of IOMMU faults:

ERROR: DMA PTE for vPFN 0xfde00 already set (to 7f83a4003 not 7e9e00083)

In this example, a 4MiB scatter/gather list entry resulted in the
successful installation of a large page @ vPFN 0xfdc00, followed by
a failed attempt to install another large page @ vPFN 0xfde00, due to
the presence of a pointer to a small page table @ 0x7f83a4000.

To address this problem, compute the number of large pages that fit
into a given scatter/gather list entry, and use it to derive the
last vPFN covered by the large page(s).

Cc: stable@vger.kernel.org
Signed-off-by: Christian Zander <christian@nervanasys.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-13 20:32:50 +01:00