Add SM8350 qcom iommu implementation to the table of
qcom_smmu_impl_of_match table which brings in iommu support for SM8350
SoC
Signed-off-by: NVinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20210115090322.2287538-2-vkoul@kernel.orgSigned-off-by: NWill Deacon <will@kernel.org>

The primary SMMU found in Qualcomm SC8180X platform needs to use the
Qualcomm implementation, so add a specific compatible for this.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20210121014005.1612382-2-bjorn.andersson@linaro.orgSigned-off-by: NWill Deacon <will@kernel.org>

linux/dma-map-ops.h is included more than once, Remove the one that
isn't necessary.
Signed-off-by: NTian Tao <tiantao6@hisilicon.com>
Acked-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/1609118774-10083-1-git-send-email-tiantao6@hisilicon.comSigned-off-by: NWill Deacon <will@kernel.org>

SDM630 and MSM8998 are among the SoCs that use Qualcomm's implementation
of SMMUv2 which has already proven to be problematic over the years. Add
their compatibles to the lookup list to prevent the platforms from being
shut down by the hypervisor at MMU probe.
Signed-off-by: NKonrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: NAngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Link: https://lore.kernel.org/r/20210109165622.149777-1-konrad.dybcio@somainline.orgSigned-off-by: NWill Deacon <will@kernel.org>

The VT-d hardware will ignore those Addr bits which have been masked by
the AM field in the PASID-based-IOTLB invalidation descriptor. As the
result, if the starting address in the descriptor is not aligned with
the address mask, some IOTLB caches might not invalidate. Hence people
will see below errors.

[ 1093.704661] dmar_fault: 29 callbacks suppressed
[ 1093.704664] DMAR: DRHD: handling fault status reg 3
[ 1093.712738] DMAR: [DMA Read] Request device [7a:02.0] PASID 2
               fault addr 7f81c968d000 [fault reason 113]
               SM: Present bit in first-level paging entry is clear

Fix this by using aligned address for PASID-based-IOTLB invalidation.

Fixes: 1c4f88b7 ("iommu/vt-d: Shared virtual address in scalable mode")
Reported-and-tested-by: NGuo Kaijie <Kaijie.Guo@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201231005323.2178523-2-baolu.lu@linux.intel.comSigned-off-by: NWill Deacon <will@kernel.org>

iommu_flush_dev_iotlb() is called to invalidate caches on a device but
only loops over the devices which are fully-attached to the domain. For
sub-devices, this is ineffective and can result in invalid caching
entries left on the device.

Fix the missing invalidation by adding a loop over the subdevices and
ensuring that 'domain->has_iotlb_device' is updated when attaching to
subdevices.

Fixes: 67b8e02b ("iommu/vt-d: Aux-domain specific domain attach/detach")
Signed-off-by: NLiu Yi L <yi.l.liu@intel.com>
Acked-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/1609949037-25291-4-git-send-email-yi.l.liu@intel.comSigned-off-by: NWill Deacon <will@kernel.org>

The aux-domain attach/detach are not tracked, some data structures might
be used after free. This causes general protection faults when multiple
subdevices are created and assigned to a same guest machine:

  | general protection fault, probably for non-canonical address 0xdead000000000100: 0000 [#1] SMP NOPTI
  | RIP: 0010:intel_iommu_aux_detach_device+0x12a/0x1f0
  | [...]
  | Call Trace:
  |  iommu_aux_detach_device+0x24/0x70
  |  vfio_mdev_detach_domain+0x3b/0x60
  |  ? vfio_mdev_set_domain+0x50/0x50
  |  iommu_group_for_each_dev+0x4f/0x80
  |  vfio_iommu_detach_group.isra.0+0x22/0x30
  |  vfio_iommu_type1_detach_group.cold+0x71/0x211
  |  ? find_exported_symbol_in_section+0x4a/0xd0
  |  ? each_symbol_section+0x28/0x50
  |  __vfio_group_unset_container+0x4d/0x150
  |  vfio_group_try_dissolve_container+0x25/0x30
  |  vfio_group_put_external_user+0x13/0x20
  |  kvm_vfio_group_put_external_user+0x27/0x40 [kvm]
  |  kvm_vfio_destroy+0x45/0xb0 [kvm]
  |  kvm_put_kvm+0x1bb/0x2e0 [kvm]
  |  kvm_vm_release+0x22/0x30 [kvm]
  |  __fput+0xcc/0x260
  |  ____fput+0xe/0x10
  |  task_work_run+0x8f/0xb0
  |  do_exit+0x358/0xaf0
  |  ? wake_up_state+0x10/0x20
  |  ? signal_wake_up_state+0x1a/0x30
  |  do_group_exit+0x47/0xb0
  |  __x64_sys_exit_group+0x18/0x20
  |  do_syscall_64+0x57/0x1d0
  |  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix the crash by tracking the subdevices when attaching and detaching
aux-domains.

Fixes: 67b8e02b ("iommu/vt-d: Aux-domain specific domain attach/detach")
Co-developed-by: NXin Zeng <xin.zeng@intel.com>
Signed-off-by: NXin Zeng <xin.zeng@intel.com>
Signed-off-by: NLiu Yi L <yi.l.liu@intel.com>
Acked-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/1609949037-25291-3-git-send-email-yi.l.liu@intel.comSigned-off-by: NWill Deacon <will@kernel.org>

'struct intel_svm' is shared by all devices bound to a give process,
but records only a single pointer to a 'struct intel_iommu'. Consequently,
cache invalidations may only be applied to a single DMAR unit, and are
erroneously skipped for the other devices.

In preparation for fixing this, rework the structures so that the iommu
pointer resides in 'struct intel_svm_dev', allowing 'struct intel_svm'
to track them in its device list.

Fixes: 1c4f88b7 ("iommu/vt-d: Shared virtual address in scalable mode")
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Raj Ashok <ashok.raj@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Reported-by: NGuo Kaijie <Kaijie.Guo@intel.com>
Reported-by: NXin Zeng <xin.zeng@intel.com>
Signed-off-by: NGuo Kaijie <Kaijie.Guo@intel.com>
Signed-off-by: NXin Zeng <xin.zeng@intel.com>
Signed-off-by: NLiu Yi L <yi.l.liu@intel.com>
Tested-by: NGuo Kaijie <Kaijie.Guo@intel.com>
Cc: stable@vger.kernel.org # v5.0+
Acked-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/1609949037-25291-2-git-send-email-yi.l.liu@intel.comSigned-off-by: NWill Deacon <will@kernel.org>

On SM8150 it's occasionally observed that the boot hangs in between the
writing of SMEs and context banks in arm_smmu_device_reset().

The problem seems to coincide with a display refresh happening after
updating the stream mapping, but before clearing - and there by
disabling translation - the context bank picked to emulate translation
bypass.

Resolve this by explicitly disabling the bypass context already in
cfg_probe.

Fixes: f9081b8f ("iommu/arm-smmu-qcom: Implement S2CR quirk")
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20210106005038.4152731-1-bjorn.andersson@linaro.orgSigned-off-by: NWill Deacon <will@kernel.org>

Lock(&iommu->lock) without disabling irq causes lockdep warnings.

========================================================
WARNING: possible irq lock inversion dependency detected
5.11.0-rc1+ #828 Not tainted
--------------------------------------------------------
kworker/0:1H/120 just changed the state of lock:
ffffffffad9ea1b8 (device_domain_lock){..-.}-{2:2}, at:
iommu_flush_dev_iotlb.part.0+0x32/0x120
but this lock took another, SOFTIRQ-unsafe lock in the past:
 (&iommu->lock){+.+.}-{2:2}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&iommu->lock);
                               local_irq_disable();
                               lock(device_domain_lock);
                               lock(&iommu->lock);
  <Interrupt>
    lock(device_domain_lock);

 *** DEADLOCK ***
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201231005323.2178523-5-baolu.lu@linux.intel.comSigned-off-by: NWill Deacon <will@kernel.org>

This reverts commit 65f746e8.

As commit 8a473dba ("drm/i915: Fix DMA mapped scatterlist walks") and
commit 934941ed ("drm/i915: Fix DMA mapped scatterlist lookup") fixed
the DMA scatterlist limitations in the i915 driver, remove this temporary
workaround.

Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Tom Murphy <murphyt7@tcd.ie>
Cc: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201231005323.2178523-4-baolu.lu@linux.intel.comSigned-off-by: NWill Deacon <will@kernel.org>

Use IS_ALIGNED() instead. Otherwise, an unaligned address will be ignored.

Fixes: 33cd6e64 ("iommu/vt-d: Flush PASID-based iotlb for iova over first level")
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201231005323.2178523-1-baolu.lu@linux.intel.comSigned-off-by: NWill Deacon <will@kernel.org>

The AMD IOMMU initialisation registers the IRQ remapping domain for
each IOMMU before doing the final sanity check that every I/OAPIC is
covered.

This means that the AMD irq_remapping_select() function gets invoked
even when IRQ remapping has been disabled, eventually leading to a NULL
pointer dereference in alloc_irq_table().

Unfortunately, the IVRS isn't fully parsed early enough that the sanity
check can be done in time to registering the IRQ domain altogether.
Doing that would be nice, but is a larger and more error-prone task. The
simple fix is just for irq_remapping_select() to refuse to report a
match when IRQ remapping has disabled.

Link: https://lore.kernel.org/lkml/ed4be9b4-24ac-7128-c522-7ef359e8185d@gmx.at
Fixes: a1a785b5 ("iommu/amd: Implement select() method on remapping irqdomain")
Reported-by: NJohnathan Smithinovic <johnathan.smithinovic@gmx.at>
Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Link: https://lore.kernel.org/r/04bbe8bca87f81a3cfa93ec4299e53f47e00e5b3.camel@infradead.orgSigned-off-by: NWill Deacon <will@kernel.org>

When I made the INTCAPXT support stop gratuitously pretending to be MSI,
I missed the fact that iommu_setup_msi() also sets the ->int_enabled
flag. I missed this in the iommu_setup_intcapxt() code path, which means
that a resume from suspend will try to allocate the IRQ domains again,
accidentally re-enabling interrupts as it does, resulting in much sadness.

Lift out the bit which sets iommu->int_enabled into the iommu_init_irq()
function which is also where it gets checked.

Link: https://lore.kernel.org/r/20210104132250.GE32151@zn.tnic/
Fixes: d1adcfbb ("iommu/amd: Fix IOMMU interrupt generation in X2APIC mode")
Reported-by: NBorislav Petkov <bp@alien8.de>
Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Tested-by: NBorislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/50cd5f55be8ead0937ac315cd2f5b89364f6a9a5.camel@infradead.orgSigned-off-by: NWill Deacon <will@kernel.org>

When irq_domain_get_irq_data() or irqd_cfg() fails
at i == 0, data allocated by kzalloc() has not been
freed before returning, which leads to memleak.

Fixes: b106ee63 ("irq_remapping/vt-d: Enhance Intel IR driver to support hierarchical irqdomains")
Signed-off-by: NDinghao Liu <dinghao.liu@zju.edu.cn>
Acked-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210105051837.32118-1-dinghao.liu@zju.edu.cnSigned-off-by: NWill Deacon <will@kernel.org>

Replace misspelled 'doamin' with 'domain' in several comments.
Signed-off-by: NStefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20201222164232.88795-1-sgarzare@redhat.comSigned-off-by: NWill Deacon <will@kernel.org>

Currently, macros related to the interrupt remapping table length are
defined separately. This has resulted in an oversight in which one of
the macros were missed when changing the length. To prevent this,
redefine the macros to add built-in sanity check.

Also, rename macros to use the name of the DTE[IntTabLen] field as
specified in the AMD IOMMU specification. There is no functional change.
Suggested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: NTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: NSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Will Deacon <will@kernel.org>
Cc: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Reviewed-by: NJerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/20201210162436.126321-1-suravee.suthikulpanit@amd.comSigned-off-by: NWill Deacon <will@kernel.org>

The function has a single caller, so open code it there and take
advantage of the precalculated page count variable.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20201209112019.2625029-1-hch@lst.deSigned-off-by: NWill Deacon <will@kernel.org>

The only user of tlb_flush_leaf is a particularly hairy corner of the
Arm short-descriptor code, which wants a synchronous invalidation to
minimise the races inherent in trying to split a large page mapping.
This is already far enough into "here be dragons" territory that no
sensible caller should ever hit it, and thus it really doesn't need
optimising. Although using tlb_flush_walk there may technically be
more heavyweight than needed, it does the job and saves everyone else
having to carry around useless baggage.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Reviewed-by: NSteven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/9844ab0c5cb3da8b2f89c6c2da16941910702b41.1606324115.git.robin.murphy@arm.comSigned-off-by: NWill Deacon <will@kernel.org>

It has no user outside iova.c
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1607020492-189471-4-git-send-email-john.garry@huawei.comSigned-off-by: NWill Deacon <will@kernel.org>

It is not used outside iova.c
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1607020492-189471-3-git-send-email-john.garry@huawei.comSigned-off-by: NWill Deacon <will@kernel.org>

Function split_and_remove_iova() has not been referenced since commit
e70b081c ("iommu/vt-d: Remove IOVA handling code from the non-dma_ops
path"), so delete it.
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1607020492-189471-2-git-send-email-john.garry@huawei.comSigned-off-by: NWill Deacon <will@kernel.org>

The 'level' parameter to the iopte_type() macro is unused, so remove it.
Signed-off-by: NKunkun Jiang <jiangkunkun@huawei.com>
Link: https://lore.kernel.org/r/20201207120150.1891-1-jiangkunkun@huawei.comSigned-off-by: NWill Deacon <will@kernel.org>

Although handling a mapping request with no permissions is a
trivial no-op, defer the early return until after the size/range
checks so that we are consistent with other mapping requests.
Signed-off-by: NKeqian Zhu <zhukeqian1@huawei.com>
Link: https://lore.kernel.org/r/20201207115758.9400-1-zhukeqian1@huawei.comSigned-off-by: NWill Deacon <will@kernel.org>

According to the AMD IOMMU spec, the commit 73db2fc5
("iommu/amd: Increase interrupt remapping table limit to 512 entries")
also requires the interrupt table length (IntTabLen) to be set to 9
(power of 2) in the device table mapping entry (DTE).

Fixes: 73db2fc5 ("iommu/amd: Increase interrupt remapping table limit to 512 entries")
Reported-by: NJerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: NSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reviewed-by: NJerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/20201207091920.3052-1-suravee.suthikulpanit@amd.comSigned-off-by: NWill Deacon <will@kernel.org>

Currently direct_mapping always use the smallest pgsize which is SZ_4K
normally to mapping. This is unnecessary. we could gather the size, and
call iommu_map then, iommu_map could decide how to map better with the
just right pgsize.

>From the original comment, we should take care overlap, otherwise,
iommu_map may return -EEXIST. In this overlap case, we should map the
previous region before overlap firstly. then map the left part.

Each a iommu device will call this direct_mapping when its iommu
initialize, This patch is effective to improve the boot/initialization
time especially while it only needs level 1 mapping.
Signed-off-by: NAnan Sun <anan.sun@mediatek.com>
Signed-off-by: NYong Wu <yong.wu@mediatek.com>
Link: https://lore.kernel.org/r/20201207093553.8635-1-yong.wu@mediatek.comSigned-off-by: NWill Deacon <will@kernel.org>

commit a491bb19 ("iommu/hyper-v: Implement select() method on remapping
irqdomain") restricted the irq_domain_ops::select() callback to match on
I/O-APIC index 0, which was correct until the parameter was changed to
carry the I/O APIC ID in commit f36a74b9.

If the ID is not 0 then the match fails. Therefore I/O-APIC init fails to
retrieve the parent irqdomain for the I/O-APIC resulting in a boot panic:

    kernel BUG at arch/x86/kernel/apic/io_apic.c:2408!

Fix it by matching the I/O-APIC independent of the ID as there is only one
I/O APIC emulated by Hyper-V.

[ tglx: Amended changelog ]

Fixes: f36a74b9 ("x86/ioapic: Use I/O-APIC ID for finding irqdomain, not index")
Signed-off-by: NDexuan Cui <decui@microsoft.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Link: https://lore.kernel.org/r/20201202004510.1818-1-decui@microsoft.com

Both find_iova() and __free_iova() take iova_rbtree_lock,
there is no reason to take and release it twice inside
free_iova().

Fold them into one critical section by calling the unlock
versions instead.
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1605608734-84416-5-git-send-email-john.garry@huawei.comSigned-off-by: NWill Deacon <will@kernel.org>

There is no reason to use GFP_ATOMIC in a 'suspend' function.
Use GFP_KERNEL instead to give more opportunities to allocate the
requested memory.
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20201030182630.5154-1-christophe.jaillet@wanadoo.frSigned-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201201013149.2466272-2-baolu.lu@linux.intel.comSigned-off-by: NWill Deacon <will@kernel.org>

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/iommu/intel/iommu.c:5643:27: warning: variable 'last_pfn' set but not used [-Wunused-but-set-variable]
5643 |  unsigned long start_pfn, last_pfn;
     |                           ^~~~~~~~

This variable is never used, so remove it.

Fixes: 2a2b8eaa ("iommu: Handle freelists when using deferred flushing in iommu drivers")
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20201127013308.1833610-1-baolu.lu@linux.intel.comSigned-off-by: NWill Deacon <will@kernel.org>

Although iommu_group_get() in iommu_probe_device() will always succeed
thanks to __iommu_probe_device() creating the group if it's not present,
it's still worth initialising 'ret' to -ENODEV in case this path is
reachable in the future.

For now, this patch results in no functional change.
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20201126133825.3643852-1-yangyingliang@huawei.comSigned-off-by: NWill Deacon <will@kernel.org>

My virtual IOMMU implementation is whining that the guest is reading a
register that doesn't exist. Only read the VCCAP_REG if the corresponding
capability is set in ECAP_REG to indicate that it actually exists.

Fixes: 3375303e ("iommu/vt-d: Add custom allocator for IOASID")
Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: NLiu Yi L <yi.l.liu@intel.com>
Cc: stable@vger.kernel.org # v5.7+
Acked-by: NLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/de32b150ffaa752e0cff8571b17dfb1213fbe71c.camel@infradead.orgSigned-off-by: NWill Deacon <will@kernel.org>

Fix the checkpatch warning for space required before the open
parenthesis.
Signed-off-by: NSai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Acked-by: NWill Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/0b4c3718a87992f11340a1cdd99fd746c647e485.1606287059.git.saiprakash.ranjan@codeaurora.orgSigned-off-by: NWill Deacon <will@kernel.org>

Use table and of_match_node() to match qcom implementation
instead of multiple of_device_compatible() calls for each
QCOM SMMU implementation.
Signed-off-by: NSai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Acked-by: NWill Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/4e11899bc02102a6e6155db215911e8b5aaba950.1606287059.git.saiprakash.ranjan@codeaurora.orgSigned-off-by: NWill Deacon <will@kernel.org>

Now that we have a struct io_pgtable_domain_attr with quirks,
use that for non_strict mode as well thereby removing the need
for more members of arm_smmu_domain in the future.
Signed-off-by: NSai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/r/c191265f3db1f6b3e136d4057ca917666680a066.1606287059.git.saiprakash.ranjan@codeaurora.orgSigned-off-by: NWill Deacon <will@kernel.org>

Add support for domain attribute DOMAIN_ATTR_IO_PGTABLE_CFG
to get/set pagetable configuration data which initially will
be used to set quirks and later can be extended to include
other pagetable configuration data.
Signed-off-by: NSai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/r/2ab52ced2f853115c32461259a075a2877feffa6.1606287059.git.saiprakash.ranjan@codeaurora.orgSigned-off-by: NWill Deacon <will@kernel.org>

Add a quirk IO_PGTABLE_QUIRK_ARM_OUTER_WBWA to override
the outer-cacheability attributes set in the TCR for a
non-coherent page table walker when using system cache.
Signed-off-by: NSai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/r/f818676b4a2a9ad1edb92721947d47db41ed6a7c.1606287059.git.saiprakash.ranjan@codeaurora.orgSigned-off-by: NWill Deacon <will@kernel.org>

"/sys/kernel/iommu_groups/<grp_id>/type" file could be read to find out the
default domain type of an iommu group. The default domain of an iommu group
doesn't change after booting and hence could be read directly. But,
after addding support to dynamically change iommu group default domain, the
above assumption no longer stays valid.

iommu group default domain type could be changed at any time by writing to
"/sys/kernel/iommu_groups/<grp_id>/type". So, take group mutex before
reading iommu group default domain type so that the user wouldn't see stale
values or iommu_group_show_type() doesn't try to derefernce stale pointers.
Signed-off-by: NSai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Sohil Mehta <sohil.mehta@intel.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Link: https://lore.kernel.org/r/20201124130604.2912899-4-baolu.lu@linux.intel.comSigned-off-by: NWill Deacon <will@kernel.org>

Presently, the default domain of an iommu group is allocated during boot
time and it cannot be changed later. So, the device would typically be
either in identity (also known as pass_through) mode or the device would be
in DMA mode as long as the machine is up and running. There is no way to
change the default domain type dynamically i.e. after booting, a device
cannot switch between identity mode and DMA mode.

But, assume a use case wherein the user trusts the device and believes that
the OS is secure enough and hence wants *only* this device to bypass IOMMU
(so that it could be high performing) whereas all the other devices to go
through IOMMU (so that the system is protected). Presently, this use case
is not supported. It will be helpful if there is some way to change the
default domain of an iommu group dynamically. Hence, add such support.

A privileged user could request the kernel to change the default domain
type of a iommu group by writing to
"/sys/kernel/iommu_groups/<grp_id>/type" file. Presently, only three values
are supported
1. identity: all the DMA transactions from the device in this group are
             *not* translated by the iommu
2. DMA: all the DMA transactions from the device in this group are
        translated by the iommu
3. auto: change to the type the device was booted with

Note:
1. Default domain of an iommu group with two or more devices cannot be
   changed.
2. The device in the iommu group shouldn't be bound to any driver.
3. The device shouldn't be assigned to user for direct access.
4. The change request will fail if any device in the group has a mandatory
   default domain type and the requested one conflicts with that.

Please see "Documentation/ABI/testing/sysfs-kernel-iommu_groups" for more
information.
Signed-off-by: NSai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Sohil Mehta <sohil.mehta@intel.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Link: https://lore.kernel.org/r/20201124130604.2912899-3-baolu.lu@linux.intel.comSigned-off-by: NWill Deacon <will@kernel.org>

So that the vendor iommu drivers are no more required to provide the
def_domain_type callback to always isolate the untrusted devices.
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Cc: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/linux-iommu/243ce89c33fe4b9da4c56ba35acebf81@huawei.com/
Link: https://lore.kernel.org/r/20201124130604.2912899-2-baolu.lu@linux.intel.comSigned-off-by: NWill Deacon <will@kernel.org>