The ACPI Virtual I/O Translation Table describes topology of
para-virtual platforms, similarly to vendor tables DMAR, IVRS and IORT.
For now it describes the relation between virtio-iommu and the endpoints
it manages.

Three steps are needed to configure DMA of endpoints:

(1) acpi_viot_init(): parse the VIOT table, find or create the fwnode
    associated to each vIOMMU device. This needs to happen after
    acpi_scan_init(), because it relies on the struct device and their
    fwnode to be available.

(2) When probing the vIOMMU device, the driver registers its IOMMU ops
    within the IOMMU subsystem. This step doesn't require any
    intervention from the VIOT driver.

(3) viot_iommu_configure(): before binding the endpoint to a driver,
    find the associated IOMMU ops. Register them, along with the
    endpoint ID, into the device's iommu_fwspec.

If step (3) happens before step (2), it is deferred until the IOMMU is
initialized, then retried.
Tested-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NJean-Philippe Brucker <jean-philippe@linaro.org>
Acked-by: NRafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20210618152059.1194210-4-jean-philippe@linaro.orgSigned-off-by: NJoerg Roedel <jroedel@suse.de>

The IOMMU in many SoC depends on the MM clocks and power-domain which
are device_initcall normally, thus the subsys_init here is not helpful.
This patch switches it to module_platform_driver which also allow the
driver built as module.

Correspondingly switch the config to tristate, and update the
iommu_ops's owner.
Signed-off-by: NYong Wu <yong.wu@mediatek.com>
Link: https://lore.kernel.org/r/20210326032337.24578-2-yong.wu@mediatek.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

This patch only adds support for building the IOMMU-v1 driver as module.
Correspondingly switch the config to tristate and update the iommu_ops's
owner to THIS_MODULE.
Signed-off-by: NYong Wu <yong.wu@mediatek.com>
Link: https://lore.kernel.org/r/20210326032337.24578-1-yong.wu@mediatek.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

This IOMMU module can be used by Unisoc's multimedia devices, such as
display, Image codec(jpeg) and a few signal processors, including
VSP(video), GSP(graphic), ISP(image), and CPP(camera pixel processor), etc.
Signed-off-by: NChunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20210305093216.201897-3-zhang.lyra@gmail.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

The sva_bind() function allows devices to access process address spaces
using a PASID (aka SSID).

(1) bind() allocates or gets an existing MMU notifier tied to the
    (domain, mm) pair. Each mm gets one PASID.

(2) Any change to the address space calls invalidate_range() which sends
    ATC invalidations (in a subsequent patch).

(3) When the process address space dies, the release() notifier disables
    the CD to allow reclaiming the page tables. Since release() has to
    be light we do not instruct device drivers to stop DMA here, we just
    ignore incoming page faults from this point onwards.

    To avoid any event 0x0a print (C_BAD_CD) we disable translation
    without clearing CD.V. PCIe Translation Requests and Page Requests
    are silently denied. Don't clear the R bit because the S bit can't
    be cleared when STALL_MODEL==0b10 (forced), and clearing R without
    clearing S is useless. Faulting transactions will stall and will be
    aborted by the IOPF handler.

(4) After stopping DMA, the device driver releases the bond by calling
    unbind(). We release the MMU notifier, free the PASID and the bond.

Three structures keep track of bonds:
* arm_smmu_bond: one per {device, mm} pair, the handle returned to the
  device driver for a bind() request.
* arm_smmu_mmu_notifier: one per {domain, mm} pair, deals with ATS/TLB
  invalidations and clearing the context descriptor on mm exit.
* arm_smmu_ctx_desc: one per mm, holds the pinned ASID and pgd.
Signed-off-by: NJean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20201106155048.997886-4-jean-philippe@linaro.orgSigned-off-by: NWill Deacon <will@kernel.org>

Let IOMMU drivers allocate a single PASID per mm. Store the mm in the
IOASID set to allow refcounting and searching mm by PASID, when handling
an I/O page fault.
Signed-off-by: NJean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201106155048.997886-3-jean-philippe@linaro.orgSigned-off-by: NWill Deacon <will@kernel.org>

This reverts commit d0511b54.

After some time it was noticed that the Tegra186 among others
were experiencing problems when making this into a module.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Allow the qcom_scm driver to be loadable as a permenent module.

This still uses the "depends on QCOM_SCM || !QCOM_SCM" bit to
ensure that drivers that call into the qcom_scm driver are
also built as modules. While not ideal in some cases its the
only safe way I can find to avoid build errors without having
those drivers select QCOM_SCM and have to force it on (as
QCOM_SCM=n can be valid for those drivers).
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
Reviewed-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: NKalle Valo <kvalo@codeaurora.org>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Maulik Shah <mkshah@codeaurora.org>
Cc: Lina Iyer <ilina@codeaurora.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Todd Kjos <tkjos@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-arm-msm@vger.kernel.org
Cc: iommu@lists.linux-foundation.org
Cc: linux-gpio@vger.kernel.org
Link: https://lore.kernel.org/r/20201106042710.55979-3-john.stultz@linaro.orgSigned-off-by: NLinus Walleij <linus.walleij@linaro.org>

With Shared Virtual Addressing (SVA), we need to mirror CPU TTBR, TCR,
MAIR and ASIDs in SMMU contexts. Each SMMU has a single ASID space split
into two sets, shared and private. Shared ASIDs correspond to those
obtained from the arch ASID allocator, and private ASIDs are used for
"classic" map/unmap DMA.

A possible conflict happens when trying to use a shared ASID that has
already been allocated for private use by the SMMU driver. This will be
addressed in a later patch by replacing the private ASID. At the
moment we return -EBUSY.

Each mm_struct shared with the SMMU will have a single context
descriptor. Add a refcount to keep track of this. It will be protected
by the global SVA lock.

Introduce a new arm-smmu-v3-sva.c file and the CONFIG_ARM_SMMU_V3_SVA
option to let users opt in SVA support.
Signed-off-by: NJean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20200918101852.582559-9-jean-philippe@linaro.orgSigned-off-by: NWill Deacon <will@kernel.org>

ipmmu-vmsa driver is also used on Renesas RZ/G{1,2} Soc's, update the
same to reflect the help description for IPMMU_VMSA config.
Signed-off-by: NLad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: NChris Paterson <Chris.Paterson2@renesas.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200911101912.20701-1-prabhakar.mahadev-lad.rj@bp.renesas.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

Move AMD Kconfig and Makefile bits down into the amd directory
with the rest of the AMD specific files.
Signed-off-by: NJerry Snitselaar <jsnitsel@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20200630200636.48600-3-jsnitsel@redhat.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

Move Intel Kconfig and Makefile bits down into intel directory
with the rest of the Intel specific files.
Signed-off-by: NJerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: NLu Baolu <baolu.lu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20200630200636.48600-2-jsnitsel@redhat.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

Avoid the overhead of the dma ops support for tiny builds that only
use the direct mapping.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Tested-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: NAlexey Kardashevskiy <aik@ozlabs.ru>

This driver shouldn't need anything architecture-specific (that isn't
under CONFIG_ARM protection already), and has already been accessible
from certain x86 configurations by virtue of the previously-cleaned-up
"ARM || IOMMU_DMA" dependency. Allow COMPILE_TEST for all architectures.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1fe2006aa98f008a2e689adba6e8c96e9197f903.1593791968.git.robin.murphy@arm.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

Wacky COMPILE_TEST dependencies based on who used to define
dev_archdata.iommu can go.

Dependencies on ARM or ARM64 already implied by the ARCH_* platform
selection can go.

The entire IOMMU_SUPPORT menu already depends on MMU, so those can go.

IOMMU_DMA is for the architecture's DMA API implementation to choose,
and its interface to IOMMU drivers is properly stubbed out if disabled,
so dependencies on or selections of that can go (AMD_IOMMU is the
current exception since the x86 drivers have to provide their own entire
dma_map_ops implementation).

Since commit ed6ccf10 ("dma-mapping: properly stub out the DMA API
for !CONFIG_HAS_DMA"), drivers which simply use the dma-mapping API
should not need to depend on HAS_DMA, so those can go.

And a long-dead option for code removed from the MSM driver 4 years ago
can also go.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/7fb9c74dc6bd12a4619ca44c92408e91352f1be0.1593791968.git.robin.murphy@arm.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

If NO_DMA=y (e.g. Sun-3 all{mod,yes}-config):

    drivers/iommu/dma-iommu.o: In function `iommu_dma_mmap':
    dma-iommu.c:(.text+0x92e): undefined reference to `dma_pgprot'

IOMMU_DMA must not be selected, unless HAS_DMA=y.

Hence fix this by making SUN50I_IOMMU depend on HAS_DMA.

Fixes: 4100b8c2 ("iommu: Add Allwinner H6 IOMMU driver")
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NMaxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200629121146.24011-1-geert@linux-m68k.orgSigned-off-by: NJoerg Roedel <jroedel@suse.de>

Current Intel SVM is designed by setting the pgd_t of the processor page
table to FLPTR field of the PASID entry. The first level translation only
supports 4 and 5 level paging structures, hence it's infeasible for the
IOMMU to share a processor's page table when it's running in 32-bit mode.
Let's disable 32bit support for now and claim support only when all the
missing pieces are ready in the future.

Fixes: 1c4f88b7 ("iommu/vt-d: Shared virtual address in scalable mode")
Suggested-by: NJoerg Roedel <jroedel@suse.de>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20200622231345.29722-2-baolu.lu@linux.intel.comSigned-off-by: NJoerg Roedel <jroedel@suse.de>

Since commit 84af7a61 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

The Allwinner H6 has introduced an IOMMU for a few DMA controllers, mostly
video related: the display engine, the video decoders / encoders, the
camera capture controller, etc.

The design is pretty simple compared to other IOMMUs found in SoCs: there's
a single instance, controlling all the masters, with a single address
space.

It also features a performance monitoring unit that allows to retrieve
various informations (per-master and global TLB accesses, hits and misses,
access latency, etc) that isn't supported at the moment.
Signed-off-by: NMaxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/d122a8670361e36fc26b4ce2674a2223d30dc4cc.1589378833.git-series.maxime@cerno.techSigned-off-by: NJoerg Roedel <jroedel@suse.de>

Although SPAPR_TCE_IOMMU itself can be compile tested on certain PowerPC
configurations, its presence makes arch/powerpc/kvm/Makefile to select
modules which do not build in such configuration.

The arch/powerpc/kvm/ modules use kvm_arch.spapr_tce_tables which exists
only with CONFIG_PPC_BOOK3S_64.  However these modules are selected when
COMPILE_TEST and SPAPR_TCE_IOMMU are chosen leading to build failures:

    In file included from arch/powerpc/include/asm/book3s/64/mmu-hash.h:20:0,
                     from arch/powerpc/kvm/book3s_64_vio_hv.c:22:
    arch/powerpc/include/asm/book3s/64/pgtable.h:17:0: error: "_PAGE_EXEC" redefined [-Werror]
     #define _PAGE_EXEC  0x00001 /* execute permission */

    In file included from arch/powerpc/include/asm/book3s/32/pgtable.h:8:0,
                     from arch/powerpc/include/asm/book3s/pgtable.h:8,
                     from arch/powerpc/include/asm/pgtable.h:18,
                     from include/linux/mm.h:95,
                     from arch/powerpc/include/asm/io.h:29,
                     from include/linux/io.h:13,
                     from include/linux/irq.h:20,
                     from arch/powerpc/include/asm/hardirq.h:6,
                     from include/linux/hardirq.h:9,
                     from include/linux/kvm_host.h:7,
                     from arch/powerpc/kvm/book3s_64_vio_hv.c:12:
    arch/powerpc/include/asm/book3s/32/hash.h:29:0: note: this is the location of the previous definition
     #define _PAGE_EXEC 0x200 /* software: exec allowed */

Fixes: e93a1695 ("iommu: Enable compile testing for some of drivers")
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200414142630.21153-1-krzk@kernel.orgSigned-off-by: NJoerg Roedel <jroedel@suse.de>

If NO_DMA=y (e.g. Sun-3 all{mod,yes}-config):

    drivers/iommu/dma-iommu.o: In function `iommu_dma_mmap':
    dma-iommu.c:(.text+0x836): undefined reference to `dma_pgprot'

IOMMU_DMA must not be selected, unless HAS_DMA=y.

Hence fix this by making MTK_IOMMU depend on HAS_DMA.
While at it, remove the dependency on ARM || ARM64, as that is already
implied by the dependency on ARCH_MEDIATEK.

Fixes: e93a1695 ("iommu: Enable compile testing for some of drivers")
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20200410143047.19691-1-geert@linux-m68k.orgSigned-off-by: NJoerg Roedel <jroedel@suse.de>

IOASID code is needed by VT-d scalable mode for PASID allocation.
Add explicit dependency such that IOASID is built-in whenever Intel
IOMMU is enabled.
Otherwise, aux domain code will fail when IOMMU is built-in and IOASID
is compiled as a module.

Fixes: 59a62337 ("iommu/vt-d: Replace Intel specific PASID allocator with IOASID")
Signed-off-by: NJacob Pan <jacob.jun.pan@linux.intel.com>
Acked-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Some of the IOMMU drivers can be compile tested to increase build
coverage.  The OMAP, Rockchip and Exynos drivers use
device.dev_archdata.iommu field which does not exist on all platforms.
The sPAPR TCE and ARM SMMU have also restrictions where they can be
built.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Now that the infrastructure changes are in place, enable virtio-iommu to
be built as a module. Remove the redundant pci_request_acs() call, since
it's not exported but is already invoked during DMA setup.
Signed-off-by: NJean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Make use of generic IOASID code to manage PASID allocation,
free, and lookup. Replace Intel specific code.
Signed-off-by: NJacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

This adds Kconfig option INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON
to make it easier for distributions to enable or disable the
Intel IOMMU scalable mode by default during kernel build.
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
	$ sed -e 's/^        /\t/' -i */Kconfig
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

By conditionally dropping support for the legacy binding and exporting
the newly introduced 'arm_smmu_impl_init()' function we can allow the
ARM SMMU driver to be built as a module.
Signed-off-by: NWill Deacon <will@kernel.org>
Tested-by: John Garry <john.garry@huawei.com> # smmu v3
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

By removing the redundant call to 'pci_request_acs()' we can allow the
ARM SMMUv3 driver to be built as a module.
Signed-off-by: NWill Deacon <will@kernel.org>
Tested-by: John Garry <john.garry@huawei.com> # smmu v3
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Currently hyperv-iommu is implemented in a x86 specific way, for
example, apic is used. So make the HYPERV_IOMMU Kconfig depend on X86
as a preparation for enabling HyperV on architecture other than x86.

Cc: Lan Tianyu <Tianyu.Lan@microsoft.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Cc: linux-hyperv@vger.kernel.org
Signed-off-by: NBoqun Feng (Microsoft) <boqun.feng@gmail.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>

Previously intel-iommu.c depended on CONFIG_AMD_IOMMU in an undesirable
way.  When CONFIG_INTEL_IOMMU_SVM=y, iommu_enable_dev_iotlb() calls PRI
interfaces (pci_reset_pri() and pci_enable_pri()), but those are only
implemented when CONFIG_PCI_PRI is enabled.

The INTEL_IOMMU_SVM Kconfig did nothing with PCI_PRI, but AMD_IOMMU selects
PCI_PRI.  So if AMD_IOMMU was enabled, intel-iommu.c got the full PRI
interfaces, but if AMD_IOMMU was not enabled, it got the PRI stubs.

Make the iommu_enable_dev_iotlb() behavior independent of AMD_IOMMU by
having INTEL_IOMMU_SVM select PCI_PRI so iommu_enable_dev_iotlb() always
uses the full implementations of PRI interfaces.
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: NJerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: NJoerg Roedel <jroedel@suse.de>
Acked-by: NJoerg Roedel <jroedel@suse.de>

Some devices might support multiple DMA address spaces, in particular
those that have the PCI PASID feature. PASID (Process Address Space ID)
allows to share process address spaces with devices (SVA), partition a
device into VM-assignable entities (VFIO mdev) or simply provide
multiple DMA address space to kernel drivers. Add a global PASID
allocator usable by different drivers at the same time. Name it I/O ASID
to avoid confusion with ASIDs allocated by arch code, which are usually
a separate ID space.

The IOASID space is global. Each device can have its own PASID space,
but by convention the IOMMU ended up having a global PASID space, so
that with SVA, each mm_struct is associated to a single PASID.

The allocator is primarily used by IOMMU subsystem but in rare occasions
drivers would like to allocate PASIDs for devices that aren't managed by
an IOMMU, using the same ID space as IOMMU.
Signed-off-by: NJean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: NJacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: NJean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Convert the AMD iommu driver to the dma-iommu api. Remove the iova
handling and reserve region code from the AMD iommu driver.
Signed-off-by: NTom Murphy <murphyt7@tcd.ie>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

The bounce page implementation depends on swiotlb. Hence, don't
switch off swiotlb if the system has untrusted devices or could
potentially be hot-added with any untrusted devices.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

The only thing remaining of the machvecs is a few checks if we are
running on an SGI UV system.  Replace those with the existing
is_uv_system() check that has been rewritten to simply check the
OEM ID directly.

That leaves us with a generic kernel that is as fast as the previous
DIG/ZX1/UV kernels, but can support all hardware.  Support for UV
and the HP SBA IOMMU is now optional based on new config options.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lkml.kernel.org/r/20190813072514.23299-27-hch@lst.deSigned-off-by: NTony Luck <tony.luck@intel.com>

The virtio IOMMU is a para-virtualized device, allowing to send IOMMU
requests such as map/unmap over virtio transport without emulating page
tables. This implementation handles ATTACH, DETACH, MAP and UNMAP
requests.

The bulk of the code transforms calls coming from the IOMMU API into
corresponding virtio requests. Mappings are kept in an interval tree
instead of page tables. A little more work is required for modular and x86
support, so for the moment the driver depends on CONFIG_VIRTIO=y and
CONFIG_ARM64.
Tested-by: NBharat Bhushan <bharat.bhushan@nxp.com>
Tested-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NJean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

For entirely dma coherent architectures there is no requirement to ever
remap dma coherent allocation.  Move all the remap and pool code under
IS_ENABLED() checks and drop the Kconfig dependency.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

There is nothing really arm64 specific in the iommu_dma_ops
implementation, so move it to dma-iommu.c and keep a lot of symbols
self-contained.  Note the implementation does depend on the
DMA_DIRECT_REMAP infrastructure for now, so we'll have to make the
DMA_IOMMU support depend on it, but this will be relaxed soon.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

On RT, iommu_dma_map_msi_msg() may be called from non-preemptible
context. This will lead to a splat with CONFIG_DEBUG_ATOMIC_SLEEP as
the function is using spin_lock (they can sleep on RT).

iommu_dma_map_msi_msg() is used to map the MSI page in the IOMMU PT
and update the MSI message with the IOVA.

Only the part to lookup for the MSI page requires to be called in
preemptible context. As the MSI page cannot change over the lifecycle
of the MSI interrupt, the lookup can be cached and re-used later on.

iomma_dma_map_msi_msg() is now split in two functions:
    - iommu_dma_prepare_msi(): This function will prepare the mapping
    in the IOMMU and store the cookie in the structure msi_desc. This
    function should be called in preemptible context.
    - iommu_dma_compose_msi_msg(): This function will update the MSI
    message with the IOVA when the device is behind an IOMMU.
Signed-off-by: NJulien Grall <julien.grall@arm.com>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Acked-by: NJoerg Roedel <jroedel@suse.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>