Commit Graph

1287 Commits

Author SHA1 Message Date
Will Deacon
04fa26c71b iommu/arm-smmu: Convert DMA buffer allocations to the managed API
The ARM SMMUv3 driver uses dma_{alloc,free}_coherent to manage its
queues and configuration data structures.

This patch converts the driver to the managed (dmam_*) API, so that
resources are freed automatically on device teardown. This greatly
simplifies the failure paths and allows us to remove a bunch of
handcrafted freeing code.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17 12:05:32 +00:00
Will Deacon
89df3a96ba iommu/arm-smmu: Remove #define for non-existent PRIQ_0_OF field
PRIQ_0_OF has been removed from the SMMUv3 architecture, so remove its
corresponding (and unused) #define from the driver.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17 12:05:32 +00:00
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
2f4bf528ec powerpc updates for 4.4
- Kconfig: remove BE-only platforms from LE kernel build from Boqun Feng
  - Refresh ps3_defconfig from Geoff Levand
  - Emit GNU & SysV hashes for the vdso from Michael Ellerman
  - Define an enum for the bolted SLB indexes from Anshuman Khandual
  - Use a local to avoid multiple calls to get_slb_shadow() from Michael Ellerman
  - Add gettimeofday() benchmark from Michael Neuling
  - Avoid link stack corruption in __get_datapage() from Michael Neuling
  - Add virt_to_pfn and use this instead of opencoding from Aneesh Kumar K.V
  - Add ppc64le_defconfig from Michael Ellerman
  - pseries: extract of_helpers module from Andy Shevchenko
  - Correct string length in pseries_of_derive_parent() from Nathan Fontenot
  - Free the MSI bitmap if it was slab allocated from Denis Kirjanov
  - Shorten irq_chip name for the SIU from Christophe Leroy
  - Wait 1s for secondaries to enter OPAL during kexec from Samuel Mendoza-Jonas
  - Fix _ALIGN_* errors due to type difference. from Aneesh Kumar K.V
  - powerpc/pseries/hvcserver: don't memset pi_buff if it is null from Colin Ian King
  - Disable hugepd for 64K page size. from Aneesh Kumar K.V
  - Differentiate between hugetlb and THP during page walk from Aneesh Kumar K.V
  - Make PCI non-optional for pseries from Michael Ellerman
  - Individual System V IPC system calls from Sam bobroff
  - Add selftest of unmuxed IPC calls from Michael Ellerman
  - discard .exit.data at runtime from Stephen Rothwell
  - Delete old orphaned PrPMC 280/2800 DTS and boot file. from Paul Gortmaker
  - Use of_get_next_parent to simplify code from Christophe Jaillet
  - Paginate some xmon output from Sam bobroff
  - Add some more elements to the xmon PACA dump from Michael Ellerman
  - Allow the tm-syscall selftest to build with old headers from Michael Ellerman
  - Run EBB selftests only on POWER8 from Denis Kirjanov
  - Drop CONFIG_TUNE_CELL in favour of CONFIG_CELL_CPU from Michael Ellerman
  - Avoid reference to potentially freed memory in prom.c from Christophe Jaillet
  - Quieten boot wrapper output with run_cmd from Geoff Levand
  - EEH fixes and cleanups from Gavin Shan
  - Fix recursive fenced PHB on Broadcom shiner adapter from Gavin Shan
  - Use of_get_next_parent() in of_get_ibm_chip_id() from Michael Ellerman
  - Fix section mismatch warning in msi_bitmap_alloc() from Denis Kirjanov
  - Fix ps3-lpm white space from Rudhresh Kumar J
  - Fix ps3-vuart null dereference from Colin King
  - nvram: Add missing kfree in error path from Christophe Jaillet
  - nvram: Fix function name in some errors messages. from Christophe Jaillet
  - drivers/macintosh: adb: fix misleading Kconfig help text from Aaro Koskinen
  - agp/uninorth: fix a memleak in create_gatt_table from Denis Kirjanov
  - cxl: Free virtual PHB when removing from Andrew Donnellan
  - scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target from Michael Ellerman
  - scripts/kconfig/Makefile: Fix KBUILD_DEFCONFIG check when building with O= from Michael Ellerman
 
  - Freescale updates from Scott: Highlights include 64-bit book3e kexec/kdump
    support, a rework of the qoriq clock driver, device tree changes including
    qoriq fman nodes, support for a new 85xx board, and some fixes.
 
  - MPC5xxx updates from Anatolij: Highlights include a driver for MPC512x
    LocalPlus Bus FIFO with its device tree binding documentation, mpc512x
    device tree updates and some minor fixes.
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Merge tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Kconfig: remove BE-only platforms from LE kernel build from Boqun
   Feng
 - Refresh ps3_defconfig from Geoff Levand
 - Emit GNU & SysV hashes for the vdso from Michael Ellerman
 - Define an enum for the bolted SLB indexes from Anshuman Khandual
 - Use a local to avoid multiple calls to get_slb_shadow() from Michael
   Ellerman
 - Add gettimeofday() benchmark from Michael Neuling
 - Avoid link stack corruption in __get_datapage() from Michael Neuling
 - Add virt_to_pfn and use this instead of opencoding from Aneesh Kumar
   K.V
 - Add ppc64le_defconfig from Michael Ellerman
 - pseries: extract of_helpers module from Andy Shevchenko
 - Correct string length in pseries_of_derive_parent() from Nathan
   Fontenot
 - Free the MSI bitmap if it was slab allocated from Denis Kirjanov
 - Shorten irq_chip name for the SIU from Christophe Leroy
 - Wait 1s for secondaries to enter OPAL during kexec from Samuel
   Mendoza-Jonas
 - Fix _ALIGN_* errors due to type difference, from Aneesh Kumar K.V
 - powerpc/pseries/hvcserver: don't memset pi_buff if it is null from
   Colin Ian King
 - Disable hugepd for 64K page size, from Aneesh Kumar K.V
 - Differentiate between hugetlb and THP during page walk from Aneesh
   Kumar K.V
 - Make PCI non-optional for pseries from Michael Ellerman
 - Individual System V IPC system calls from Sam bobroff
 - Add selftest of unmuxed IPC calls from Michael Ellerman
 - discard .exit.data at runtime from Stephen Rothwell
 - Delete old orphaned PrPMC 280/2800 DTS and boot file, from Paul
   Gortmaker
 - Use of_get_next_parent to simplify code from Christophe Jaillet
 - Paginate some xmon output from Sam bobroff
 - Add some more elements to the xmon PACA dump from Michael Ellerman
 - Allow the tm-syscall selftest to build with old headers from Michael
   Ellerman
 - Run EBB selftests only on POWER8 from Denis Kirjanov
 - Drop CONFIG_TUNE_CELL in favour of CONFIG_CELL_CPU from Michael
   Ellerman
 - Avoid reference to potentially freed memory in prom.c from Christophe
   Jaillet
 - Quieten boot wrapper output with run_cmd from Geoff Levand
 - EEH fixes and cleanups from Gavin Shan
 - Fix recursive fenced PHB on Broadcom shiner adapter from Gavin Shan
 - Use of_get_next_parent() in of_get_ibm_chip_id() from Michael
   Ellerman
 - Fix section mismatch warning in msi_bitmap_alloc() from Denis
   Kirjanov
 - Fix ps3-lpm white space from Rudhresh Kumar J
 - Fix ps3-vuart null dereference from Colin King
 - nvram: Add missing kfree in error path from Christophe Jaillet
 - nvram: Fix function name in some errors messages, from Christophe
   Jaillet
 - drivers/macintosh: adb: fix misleading Kconfig help text from Aaro
   Koskinen
 - agp/uninorth: fix a memleak in create_gatt_table from Denis Kirjanov
 - cxl: Free virtual PHB when removing from Andrew Donnellan
 - scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target from
   Michael Ellerman
 - scripts/kconfig/Makefile: Fix KBUILD_DEFCONFIG check when building
   with O= from Michael Ellerman
 - Freescale updates from Scott: Highlights include 64-bit book3e
   kexec/kdump support, a rework of the qoriq clock driver, device tree
   changes including qoriq fman nodes, support for a new 85xx board, and
   some fixes.
 - MPC5xxx updates from Anatolij: Highlights include a driver for
   MPC512x LocalPlus Bus FIFO with its device tree binding
   documentation, mpc512x device tree updates and some minor fixes.

* tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (106 commits)
  powerpc/msi: Fix section mismatch warning in msi_bitmap_alloc()
  powerpc/prom: Use of_get_next_parent() in of_get_ibm_chip_id()
  powerpc/pseries: Correct string length in pseries_of_derive_parent()
  powerpc/e6500: hw tablewalk: make sure we invalidate and write to the same tlb entry
  powerpc/mpc85xx: Add FSL QorIQ DPAA FMan support to the SoC device tree(s)
  powerpc/mpc85xx: Create dts components for the FSL QorIQ DPAA FMan
  powerpc/fsl: Add #clock-cells and clockgen label to clockgen nodes
  powerpc: handle error case in cpm_muram_alloc()
  powerpc: mpic: use IRQCHIP_SKIP_SET_WAKE instead of redundant mpic_irq_set_wake
  powerpc/book3e-64: Enable kexec
  powerpc/book3e-64/kexec: Set "r4 = 0" when entering spinloop
  powerpc/booke: Only use VIRT_PHYS_OFFSET on booke32
  powerpc/book3e-64/kexec: Enable SMP release
  powerpc/book3e-64/kexec: create an identity TLB mapping
  powerpc/book3e-64: Don't limit paca to 256 MiB
  powerpc/book3e/kdump: Enable crash_kexec_wait_realmode
  powerpc/book3e: support CONFIG_RELOCATABLE
  powerpc/booke64: Fix args to copy_and_flush
  powerpc/book3e-64: rename interrupt_end_book3e with __end_interrupts
  powerpc/e6500: kexec: Handle hardware threads
  ...
2015-11-05 23:38:43 -08:00
Linus Torvalds
933425fb00 s390: A bunch of fixes and optimizations for interrupt and time
handling.
 
 PPC: Mostly bug fixes.
 
 ARM: No big features, but many small fixes and prerequisites including:
 - a number of fixes for the arch-timer
 - introducing proper level-triggered semantics for the arch-timers
 - a series of patches to synchronously halt a guest (prerequisite for
   IRQ forwarding)
 - some tracepoint improvements
 - a tweak for the EL2 panic handlers
 - some more VGIC cleanups getting rid of redundant state
 
 x86: quite a few changes:
 
 - support for VT-d posted interrupts (i.e. PCI devices can inject
 interrupts directly into vCPUs).  This introduces a new component (in
 virt/lib/) that connects VFIO and KVM together.  The same infrastructure
 will be used for ARM interrupt forwarding as well.
 
 - more Hyper-V features, though the main one Hyper-V synthetic interrupt
 controller will have to wait for 4.5.  These will let KVM expose Hyper-V
 devices.
 
 - nested virtualization now supports VPID (same as PCID but for vCPUs)
 which makes it quite a bit faster
 
 - for future hardware that supports NVDIMM, there is support for clflushopt,
 clwb, pcommit
 
 - support for "split irqchip", i.e. LAPIC in kernel + IOAPIC/PIC/PIT in
 userspace, which reduces the attack surface of the hypervisor
 
 - obligatory smattering of SMM fixes
 
 - on the guest side, stable scheduler clock support was rewritten to not
 require help from the hypervisor.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "First batch of KVM changes for 4.4.

  s390:
     A bunch of fixes and optimizations for interrupt and time handling.

  PPC:
     Mostly bug fixes.

  ARM:
     No big features, but many small fixes and prerequisites including:

      - a number of fixes for the arch-timer

      - introducing proper level-triggered semantics for the arch-timers

      - a series of patches to synchronously halt a guest (prerequisite
        for IRQ forwarding)

      - some tracepoint improvements

      - a tweak for the EL2 panic handlers

      - some more VGIC cleanups getting rid of redundant state

  x86:
     Quite a few changes:

      - support for VT-d posted interrupts (i.e. PCI devices can inject
        interrupts directly into vCPUs).  This introduces a new
        component (in virt/lib/) that connects VFIO and KVM together.
        The same infrastructure will be used for ARM interrupt
        forwarding as well.

      - more Hyper-V features, though the main one Hyper-V synthetic
        interrupt controller will have to wait for 4.5.  These will let
        KVM expose Hyper-V devices.

      - nested virtualization now supports VPID (same as PCID but for
        vCPUs) which makes it quite a bit faster

      - for future hardware that supports NVDIMM, there is support for
        clflushopt, clwb, pcommit

      - support for "split irqchip", i.e.  LAPIC in kernel +
        IOAPIC/PIC/PIT in userspace, which reduces the attack surface of
        the hypervisor

      - obligatory smattering of SMM fixes

      - on the guest side, stable scheduler clock support was rewritten
        to not require help from the hypervisor"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (123 commits)
  KVM: VMX: Fix commit which broke PML
  KVM: x86: obey KVM_X86_QUIRK_CD_NW_CLEARED in kvm_set_cr0()
  KVM: x86: allow RSM from 64-bit mode
  KVM: VMX: fix SMEP and SMAP without EPT
  KVM: x86: move kvm_set_irq_inatomic to legacy device assignment
  KVM: device assignment: remove pointless #ifdefs
  KVM: x86: merge kvm_arch_set_irq with kvm_set_msi_inatomic
  KVM: x86: zero apic_arb_prio on reset
  drivers/hv: share Hyper-V SynIC constants with userspace
  KVM: x86: handle SMBASE as physical address in RSM
  KVM: x86: add read_phys to x86_emulate_ops
  KVM: x86: removing unused variable
  KVM: don't pointlessly leave KVM_COMPAT=y in non-KVM configs
  KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr()
  KVM: arm/arm64: Clean up vgic_retire_lr() and surroundings
  KVM: arm/arm64: Optimize away redundant LR tracking
  KVM: s390: use simple switch statement as multiplexer
  KVM: s390: drop useless newline in debugging data
  KVM: s390: SCA must not cross page boundaries
  KVM: arm: Do not indent the arguments of DECLARE_BITMAP
  ...
2015-11-05 16:26:26 -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
Linus Torvalds
e880e87488 driver core update for 4.4-rc1
Here's the "big" driver core updates for 4.4-rc1.  Primarily a bunch of
 debugfs updates, with a smattering of minor driver core fixes and
 updates as well.
 
 All have been in linux-next for a long time.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here's the "big" driver core updates for 4.4-rc1.  Primarily a bunch
  of debugfs updates, with a smattering of minor driver core fixes and
  updates as well.

  All have been in linux-next for a long time"

* tag 'driver-core-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  debugfs: Add debugfs_create_ulong()
  of: to support binding numa node to specified device in devicetree
  debugfs: Add read-only/write-only bool file ops
  debugfs: Add read-only/write-only size_t file ops
  debugfs: Add read-only/write-only x64 file ops
  debugfs: Consolidate file mode checks in debugfs_create_*()
  Revert "mm: Check if section present during memory block (un)registering"
  driver-core: platform: Provide helpers for multi-driver modules
  mm: Check if section present during memory block (un)registering
  devres: fix a for loop bounds check
  CMA: fix CONFIG_CMA_SIZE_MBYTES overflow in 64bit
  base/platform: assert that dev_pm_domain callbacks are called unconditionally
  sysfs: correctly handle short reads on PREALLOC attrs.
  base: soc: siplify ida usage
  kobject: move EXPORT_SYMBOL() macros next to corresponding definitions
  kobject: explain what kobject's sd field is
  debugfs: document that debugfs_remove*() accepts NULL and error values
  debugfs: Pass bool pointer to debugfs_create_bool()
  ACPI / EC: Fix broken 64bit big-endian users of 'global_lock'
2015-11-04 21:50:37 -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
Joerg Roedel
b61e5e80e3 iommu/vt-d: Fix return value check of parse_ioapics_under_ir()
The function returns 0 on success, so check for the right
value.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-11-02 19:57:31 +09:00
David Woodhouse
0bdec95ce5 iommu/vt-d: Fix rwxp flags in SVM device fault callback
This is the downside of using bitfields in the struct definition, rather
than doing all the explicit masking and shifting.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-28 15:14:09 +09:00
Linus Torvalds
858e904bd7 IOMMU Fixes for Linux v4.3-rc7
Two late fixes for the AMD IOMMU driver:
 
 	* One adds an additional check to the io page-fault handler to
 	  avoid a BUG_ON being hit in handle_mm_fault()
 
 	* Second patch fixes a problem with devices writing to the
 	  system management area and were blocked by the IOMMU because
 	  the driver wrongly cleared out the DTE flags allowing that
 	  access.
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Merge tag 'iommu-fixes-v4.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu fixes from Joerg Roedel:
 "Two late fixes for the AMD IOMMU driver:

   - add an additional check to the io page-fault handler to avoid a
     BUG_ON being hit in handle_mm_fault()

   - fix a problem with devices writing to the system management area
     and were blocked by the IOMMU because the driver wrongly cleared
     out the DTE flags allowing that access"

* tag 'iommu-fixes-v4.3-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/amd: Don't clear DTE flags when modifying it
  iommu/amd: Fix BUG when faulting a PROT_NONE VMA
2015-10-27 07:44:13 +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
David Woodhouse
5a10ba27d9 iommu/vt-d: Handle Caching Mode implementations of SVM
Not entirely clear why, but it seems we need to reserve PASID zero and
flush it when we make a PASID entry present.

Quite we we couldn't use the true PASID value, isn't clear.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-24 21:06:39 +02:00
Joerg Roedel
66ef950d18 iommu/vt-d: Propagate error-value from ir_parse_ioapic_hpet_scope()
Propagate the error-value from the function ir_parse_ioapic_hpet_scope()
in parse_ioapics_under_ir() and cleanup its calling loop.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-23 12:00:54 +02:00
Baoquan He
a13c8f27e4 iommu/vt-d: Adjust the return value of the parse_ioapics_under_ir
Adjust the return value of parse_ioapics_under_ir as
negative value representing failure and "0" representing
succcess. Just make it consistent with other function
implementations, and we can judge if calling is successfull
by if (!parse_ioapics_under_ir()) style.

Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-23 11:53:49 +02:00
Scott Wood
9484865447 powerpc/fsl: Move fsl_guts.h out of arch/powerpc
Freescale's Layerscape ARM chips use the same structure.

Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-10-21 18:05:50 -05:00
Joerg Roedel
1228236de5 iommu: Move default domain allocation to iommu_group_get_for_dev()
Now that the iommu core support for iommu groups is not
pci-centric anymore, we can move default domain allocation
to the bus independent iommu_group_get_for_dev() function.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-22 00:00:49 +02:00
Joerg Roedel
391811e185 iommu: Remove is_pci_dev() fall-back from iommu_group_get_for_dev
All callers of iommu_group_get_for_dev() provide a
device_group call-back now, so this fall-back is no longer
needed.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-22 00:00:49 +02:00
Joerg Roedel
af65993224 iommu/arm-smmu: Switch to device_group call-back
This converts the ARM SMMU and the SMMUv3 driver to use the
new device_group call-back.

Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-22 00:00:49 +02:00
Joerg Roedel
d5e5829715 iommu/fsl: Convert to device_group call-back
Convert the fsl pamu driver to make use of the new
device_group call-back.

Cc: Varun Sethi <Varun.Sethi@freescale.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-22 00:00:49 +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
Joerg Roedel
6eab556a40 iommu: Add generic_device_group() function
This function can be used as a device_group call-back and
just allocates one iommu-group per device.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-22 00:00:49 +02:00
Joerg Roedel
5e62292bad iommu: Export and rename iommu_group_get_for_pci_dev()
Rename that function to pci_device_group() and export it, so
that IOMMU drivers can use it as their device_group
call-back.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-22 00:00:49 +02:00
Joerg Roedel
46c6b2bc88 iommu: Revive device_group iommu-ops call-back
That call-back is currently unused, change it into a
call-back function for finding the right IOMMU group for a
device.
This is a first step to remove the hard-coded PCI dependency
in the iommu-group code.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-22 00:00:48 +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
Joerg Roedel
393c092a4d iommu/amd: Remove find_last_devid_on_pci()
The value read from the PCI header is not reliable, so
remove this code.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:30:33 +02:00
Joerg Roedel
226e889b20 iommu/amd: Remove first/last_device handling
The code is buggy and the values read from PCI are not
reliable anyway, so it is the best to just remove this code.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:30:33 +02:00
Joerg Roedel
d125941698 iommu/amd: Initialize amd_iommu_last_bdf for DEV_ALL
Also initialize the amd_iommu_last_bdf variable when a
IVHD_DEV_ALL entry is found in the ACPI table.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:30:33 +02:00
Joerg Roedel
f2c2db53b9 iommu/amd: Cleanup buffer allocation
Clean up the functions to allocate the command, event and
ppr-log buffers. Remove redundant code and change the return
value to int.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:30:33 +02:00
Joerg Roedel
deba4bce16 iommu/amd: Remove cmd_buf_size and evt_buf_size from struct amd_iommu
The driver always uses a constant size for these buffers
anyway, so there is no need to waste memory to store the
sizes.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:30:33 +02:00
Joerg Roedel
ca9cab3a5a iommu/amd: Align DTE flag definitions
No functional change.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:30:32 +02:00
Joerg Roedel
61289cbaf6 iommu/amd: Remove old alias handling code
This mostly removes the code to create dev_data structures
for alias device ids. They are not necessary anymore, as
they were only created for device ids which have no struct
pci_dev associated with it.  But these device ids are
handled in a simpler way now, so there is no need for this
code anymore.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:30:32 +02:00
Joerg Roedel
e25bfb56ea iommu/amd: Set alias DTE in do_attach/do_detach
With this we don't have to create dev_data entries for
non-existent devices (which only exist as request-ids).

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:30:32 +02:00
Joerg Roedel
272e4f99e9 iommu/amd: WARN when __[attach|detach]_device are called with irqs enabled
These functions rely on being called with IRQs disabled. Add
a WARN_ON to detect early when its not.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:29:27 +02:00
Joerg Roedel
f1dd0a8bcd iommu/amd: Don't disable IRQs in __detach_device
This function is already called with IRQs disabled already.
So no need to disable them again.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:29:27 +02:00
Joerg Roedel
150952f969 iommu/amd: Do not iterate over alias-list in __[attach|detach]_device
The alias list is handled aleady by iommu core code. No need
anymore to handle it in this part of the AMD IOMMU code

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:29:27 +02:00
Joerg Roedel
f34c73f55a iommu/amd: Do not BUG_ON in __detach_device()
The condition in the BUG_ON is an indicator of a BUG, but no
reason to kill the code path. Turn it into a WARN_ON and
bail out if it is hit.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:29:26 +02:00
Joerg Roedel
cbf3ccd09d iommu/amd: Don't clear DTE flags when modifying it
During device assignment/deassignment the flags in the DTE
get lost, which might cause spurious faults, for example
when the device tries to access the system management range.
Fix this by not clearing the flags with the rest of the DTE.

Reported-by: G. Richard Bellamy <rbellamy@pteradigm.com>
Tested-by: G. Richard Bellamy <rbellamy@pteradigm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-10-21 11:29:06 +02:00
David Woodhouse
5d52f482eb iommu/vt-d: Fix SVM IOTLB flush handling
Change the 'pages' parameter to 'unsigned long' to avoid overflow.

Fix the device-IOTLB flush parameter calculation — the size of the IOTLB
flush is indicated by the position of the least significant zero bit in
the address field. For example, a value of 0x12345f000 will flush from
0x123440000 to 0x12347ffff (256KiB).

Finally, the cap_pgsel_inv() is not relevant to SVM; the spec says that
*all* implementations must support page-selective invaliation for
"first-level" translations. So don't check for it.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-20 16:26:21 +01:00
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
Dan Carpenter
3c7c2f3288 iommu/vt-d: fix a loop in prq_event_thread()
There is an extra semi-colon on this if statement so we always break on
the first iteration.

Fixes: 0204a49609 ('iommu/vt-d: Add callback to device driver on page faults')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-18 15:26:04 +01:00
David Woodhouse
e034992160 iommu/vt-d: Fix IOTLB flushing for global pages
When flushing kernel-mode PASIDs, we need to flush global pages too.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-16 19:37:04 +01:00
David Woodhouse
7f92a2e910 iommu/vt-d: Fix address shifting in page request handler
This really should be VTD_PAGE_SHIFT, not PAGE_SHIFT. Not that we ever
really anticipate seeing this used on IA64, but we should get it right
anyway.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-16 17:22:34 +01:00
Dan Carpenter
95fb6144bb iommu/vt-d: shift wrapping bug in prq_event_thread()
The "req->addr" variable is a bit field declared as "u64 addr:52;".
The "address" variable is a u64.  We need to cast "req->addr" to a u64
before the shift or the result is truncated to 52 bits.

Fixes: a222a7f0bb ('iommu/vt-d: Implement page request handling')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 21:16:47 +01:00
David Woodhouse
26322ab55a iommu/vt-d: Fix NULL pointer dereference in page request error case
Dan Carpenter pointed out an error path which could lead to us
dereferencing the 'svm' pointer after we know it to be NULL because the
PASID lookup failed. Fix that, and make it less likely to happen again.

Fixes: a222a7f0bb ('iommu/vt-d: Implement page request handling')
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 21:16:22 +01:00
Marc Zyngier
166bdbd231 iommu/arm-smmu: Add support for MSI on SMMUv3
Despite being a platform device, the SMMUv3 is capable of signaling
interrupts using MSIs. Hook it into the platform MSI framework and
enjoy faults being reported in a new and exciting way.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
[will: tidied up the binding example and reworked most of the code]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-15 16:29:58 +01:00
Will Deacon
c88ae5de71 iommu/arm-smmu: Remove redundant calculation of gr0 base address
Since commit 1463fe44fd ("iommu/arm-smmu: Don't use VMIDs for stage-1
translations"), we don't need the GR0 base address when initialising a
context bank, so remove the useless local variable and its init code.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-15 16:29:54 +01:00
Will Deacon
c0733a2cf3 iommu/arm-smmu: Fix error checking for ASID and VMID allocation
The bitmap allocator returns an int, which is one of the standard
negative values on failure. Rather than assigning this straight to a
u16 (like we do for the ASID and VMID callers), which means that we
won't detect failure correctly, use an int for the purposes of error
checking.

Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-15 16:29:47 +01:00
David Woodhouse
5cec753709 iommu/vt-d: Implement SVM_FLAG_SUPERVISOR_MODE for kernel access
This is only usable for the static 1:1 mapping of physical memory.

Any access to vmalloc or module regions will require some way of doing
an IOTLB flush. It's theoretically possible to hook into the
tlb_flush_kernel_range() function, but that seems like overkill — most
of the addresses accessed through a kernel PASID *will* be in the 1:1
mapping.

If we really need to allow access to more interesting kernel regions,
then the answer will probably be an explicit IOTLB flush call after use,
akin to the DMA API's unmap function.

In fact, it might be worth introducing that sooner rather than later, and
making it just BUG() if the address isn't in the static 1:1 mapping.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2015-10-15 15:52:21 +01:00