Pull iommu fixes from Joerg Roedel:
- Fix a device-stall problem in bad io-page-fault setups (faults
received from devices with no supporting domain attached).
- Context flush fix for Intel VT-d.
- Do not allow non-read+non-write mapping through iommufd as most
implementations can not handle that.
- Fix a possible infinite-loop issue in map_pages() path.
- Add Jean-Philippe as reviewer for SMMUv3 SVA support
* tag 'iommu-fixes-v6.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux:
MAINTAINERS: Add Jean-Philippe as SMMUv3 SVA reviewer
iommu: Do not return 0 from map_pages if it doesn't do anything
iommufd: Do not allow creating areas without READ or WRITE
iommu/vt-d: Fix incorrect domain ID in context flush helper
iommu: Handle iommu faults for a bad iopf setup
These three implementations of map_pages() all succeed if a mapping is
requested with no read or write. Since they return back to __iommu_map()
leaving the mapped output as 0 it triggers an infinite loop. Therefore
nothing is using no-access protection bits.
Further, VFIO and iommufd rely on iommu_iova_to_phys() to get back PFNs
stored by map, if iommu_map() succeeds but iommu_iova_to_phys() fails that
will create serious bugs.
Thus remove this never used "nothing to do" concept and just fail map
immediately.
Fixes: e5fc9753b1 ("iommu/io-pgtable: Add ARMv7 short descriptor support")
Fixes: e1d3c0fd70 ("iommu: add ARM LPAE page table allocator")
Fixes: 745ef1092b ("iommu/io-pgtable: Move Apple DART support to its own file")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/2-v1-1211e1294c27+4b1-iommu_no_prot_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This results in passing 0 or just IOMMU_CACHE to iommu_map(). Most of
the page table formats don't like this:
amdv1 - -EINVAL
armv7s - returns 0, doesn't update mapped
arm-lpae - returns 0 doesn't update mapped
dart - returns 0, doesn't update mapped
VT-D - returns -EINVAL
Unfortunately the three formats that return 0 cause serious problems:
- Returning ret = but not uppdating mapped from domain->map_pages()
causes an infinite loop in __iommu_map()
- Not writing ioptes means that VFIO/iommufd have no way to recover them
and we will have memory leaks and worse during unmap
Since almost nothing can support this, and it is a useless thing to do,
block it early in iommufd.
Cc: stable@kernel.org
Fixes: aad37e71d5 ("iommufd: IOCTLs for the io_pagetable")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/1-v1-1211e1294c27+4b1-iommu_no_prot_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The iommu_report_device_fault function was updated to return void while
assuming that drivers only need to call iommu_report_device_fault() for
reporting an iopf. This implementation causes following problems:
1. The drivers rely on the core code to call it's page_reponse,
however, when a fault is received and no fault capable domain is
attached / iopf_param is NULL, the ops->page_response is NOT called
causing the device to stall in case the fault type was PAGE_REQ.
2. The arm_smmu_v3 driver relies on the returned value to log errors
returning void from iommu_report_device_fault causes these events to
be missed while logging.
Modify the iommu_report_device_fault function to return -EINVAL for
cases where no fault capable domain is attached or iopf_param was NULL
and calls back to the driver (ops->page_response) in case the fault type
was IOMMU_FAULT_PAGE_REQ. The returned value can be used by the drivers
to log the fault/event as needed.
Reported-by: Kunkun Jiang <jiangkunkun@huawei.com>
Closes: https://lore.kernel.org/all/6147caf0-b9a0-30ca-795e-a1aa502a5c51@huawei.com/
Fixes: 3dfa64aecb ("iommu: Make iommu_report_device_fault() return void")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20240816104906.1010626-1-praan@google.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Pull iommufd fixes from Jason Gunthorpe:
- Incorrect error unwind in iommufd_device_do_replace()
- Correct a sparse warning missing static
* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd:
iommufd/selftest: Make dirty_ops static
iommufd/device: Fix hwpt at err_unresv in iommufd_device_do_replace()
When iommu_report_device_fault gets called with a partial fault it is
supposed to collect the fault into the group and then return.
Instead the return was accidently deleted which results in trying to
process the fault and an eventual crash.
Deleting the return was a typo, put it back.
Fixes: 3dfa64aecb ("iommu: Make iommu_report_device_fault() return void")
Signed-off-by: Barak Biber <bbiber@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/0-v1-e7153d9c8cee+1c6-iommu_fault_fix_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Pull iommu fixes from Will Deacon:
"We're still resolving a regression with the handling of unexpected
page faults on SMMUv3, but we're not quite there with a fix yet.
- Fix NULL dereference when freeing domain in Unisoc SPRD driver
- Separate assignment statements with semicolons in AMD page-table
code
- Fix Tegra erratum workaround when the CPU is using 16KiB pages"
* tag 'iommu-fixes-v6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux:
iommu: arm-smmu: Fix Tegra workaround for PAGE_SIZE mappings
iommu/amd: Convert comma to semicolon
iommu: sprd: Avoid NULL deref in sprd_iommu_hw_en
Pull virtio updates from Michael Tsirkin:
"Several new features here:
- Virtio find vqs API has been reworked (required to fix the
scalability issue we have with adminq, which I hope to merge later
in the cycle)
- vDPA driver for Marvell OCTEON
- virtio fs performance improvement
- mlx5 migration speedups
Fixes, cleanups all over the place"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (56 commits)
virtio: rename virtio_find_vqs_info() to virtio_find_vqs()
virtio: remove unused virtio_find_vqs() and virtio_find_vqs_ctx() helpers
virtio: convert the rest virtio_find_vqs() users to virtio_find_vqs_info()
virtio_balloon: convert to use virtio_find_vqs_info()
virtiofs: convert to use virtio_find_vqs_info()
scsi: virtio_scsi: convert to use virtio_find_vqs_info()
virtio_net: convert to use virtio_find_vqs_info()
virtio_crypto: convert to use virtio_find_vqs_info()
virtio_console: convert to use virtio_find_vqs_info()
virtio_blk: convert to use virtio_find_vqs_info()
virtio: rename find_vqs_info() op to find_vqs()
virtio: remove the original find_vqs() op
virtio: call virtio_find_vqs_info() from virtio_find_single_vq() directly
virtio: convert find_vqs() op implementations to find_vqs_info()
virtio_pci: convert vp_*find_vqs() ops to find_vqs_info()
virtio: introduce virtio_queue_info struct and find_vqs_info() config op
virtio: make virtio_find_single_vq() call virtio_find_vqs()
virtio: make virtio_find_vqs() call virtio_find_vqs_ctx()
caif_virtio: use virtio_find_single_vq() for single virtqueue finding
vdpa/mlx5: Don't enable non-active VQs in .set_vq_ready()
...
Pull dma-mapping updates from Christoph Hellwig:
- reduce duplicate swiotlb pool lookups (Michael Kelley)
- minor small fixes (Yicong Yang, Yang Li)
* tag 'dma-mapping-6.11-2024-07-19' of git://git.infradead.org/users/hch/dma-mapping:
swiotlb: fix kernel-doc description for swiotlb_del_transient
swiotlb: reduce swiotlb pool lookups
dma-mapping: benchmark: Don't starve others when doing the test
Pull iommu updates from Will Deacon:
"Core:
- Support for the "ats-supported" device-tree property
- Removal of the 'ops' field from 'struct iommu_fwspec'
- Introduction of iommu_paging_domain_alloc() and partial conversion
of existing users
- Introduce 'struct iommu_attach_handle' and provide corresponding
IOMMU interfaces which will be used by the IOMMUFD subsystem
- Remove stale documentation
- Add missing MODULE_DESCRIPTION() macro
- Misc cleanups
Allwinner Sun50i:
- Ensure bypass mode is disabled on H616 SoCs
- Ensure page-tables are allocated below 4GiB for the 32-bit
page-table walker
- Add new device-tree compatible strings
AMD Vi:
- Use try_cmpxchg64() instead of cmpxchg64() when updating pte
Arm SMMUv2:
- Print much more useful information on context faults
- Fix Qualcomm TBU probing when CONFIG_ARM_SMMU_QCOM_DEBUG=n
- Add new Qualcomm device-tree bindings
Arm SMMUv3:
- Support for hardware update of access/dirty bits and reporting via
IOMMUFD
- More driver rework from Jason, this time updating the PASID/SVA
support to prepare for full IOMMUFD support
- Add missing MODULE_DESCRIPTION() macro
- Minor fixes and cleanups
NVIDIA Tegra:
- Fix for benign fwspec initialisation issue exposed by rework on the
core branch
Intel VT-d:
- Use try_cmpxchg64() instead of cmpxchg64() when updating pte
- Use READ_ONCE() to read volatile descriptor status
- Remove support for handling Execute-Requested requests
- Avoid calling iommu_domain_alloc()
- Minor fixes and refactoring
Qualcomm MSM:
- Updates to the device-tree bindings"
* tag 'iommu-updates-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux: (72 commits)
iommu/tegra-smmu: Pass correct fwnode to iommu_fwspec_init()
iommu/vt-d: Fix identity map bounds in si_domain_init()
iommu: Move IOMMU_DIRTY_NO_CLEAR define
dt-bindings: iommu: Convert msm,iommu-v0 to yaml
iommu/vt-d: Fix aligned pages in calculate_psi_aligned_address()
iommu/vt-d: Limit max address mask to MAX_AGAW_PFN_WIDTH
docs: iommu: Remove outdated Documentation/userspace-api/iommu.rst
arm64: dts: fvp: Enable PCIe ATS for Base RevC FVP
iommu/of: Support ats-supported device-tree property
dt-bindings: PCI: generic: Add ats-supported property
iommu: Remove iommu_fwspec ops
OF: Simplify of_iommu_configure()
ACPI: Retire acpi_iommu_fwspec_ops()
iommu: Resolve fwspec ops automatically
iommu/mediatek-v1: Clean up redundant fwspec checks
RDMA/usnic: Use iommu_paging_domain_alloc()
wifi: ath11k: Use iommu_paging_domain_alloc()
wifi: ath10k: Use iommu_paging_domain_alloc()
drm/msm: Use iommu_paging_domain_alloc()
vhost-vdpa: Use iommu_paging_domain_alloc()
...
Pull iommufd updates from Jason Gunthorpe:
- The iova_bitmap logic for efficiently reporting dirty pages back to
userspace has a few more tricky corner case bugs that have been
resolved and backed with new tests.
The revised version has simpler logic.
- Shared branch with iommu for handle support when doing domain attach.
Handles allow the domain owner to include additional private data on
a per-device basis.
- IO Page Fault Reporting to userspace via iommufd. Page faults can be
generated on fault capable HWPTs when a translation is not present.
Routing them to userspace would allow a VMM to be able to virtualize
them into an emulated vIOMMU. This is the next step to fully enabling
vSVA support.
* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (26 commits)
iommufd: Put constants for all the uAPI enums
iommufd: Fix error pointer checking
iommufd: Add check on user response code
iommufd: Remove IOMMUFD_PAGE_RESP_FAILURE
iommufd: Require drivers to supply the cache_invalidate_user ops
iommufd/selftest: Add coverage for IOPF test
iommufd/selftest: Add IOPF support for mock device
iommufd: Associate fault object with iommufd_hw_pgtable
iommufd: Fault-capable hwpt attach/detach/replace
iommufd: Add iommufd fault object
iommufd: Add fault and response message definitions
iommu: Extend domain attach group with handle support
iommu: Add attach handle to struct iopf_group
iommu: Remove sva handle list
iommu: Introduce domain attachment handle
iommufd/iova_bitmap: Remove iterator logic
iommufd/iova_bitmap: Dynamic pinning on iova_bitmap_set()
iommufd/iova_bitmap: Consolidate iova_bitmap_set exit conditionals
iommufd/iova_bitmap: Move initial pinning to iova_bitmap_for_each()
iommufd/iova_bitmap: Cache mapped length in iova_bitmap_map struct
...
* iommu/iommufd/paging-domain-alloc:
RDMA/usnic: Use iommu_paging_domain_alloc()
wifi: ath11k: Use iommu_paging_domain_alloc()
wifi: ath10k: Use iommu_paging_domain_alloc()
drm/msm: Use iommu_paging_domain_alloc()
vhost-vdpa: Use iommu_paging_domain_alloc()
vfio/type1: Use iommu_paging_domain_alloc()
iommufd: Use iommu_paging_domain_alloc()
iommu: Add iommu_paging_domain_alloc() interface
* iommu/iommufd/attach-handles:
iommu: Extend domain attach group with handle support
iommu: Add attach handle to struct iopf_group
iommu: Remove sva handle list
iommu: Introduce domain attachment handle
* iommu/intel/vt-d:
iommu/vt-d: Fix identity map bounds in si_domain_init()
iommu/vt-d: Fix aligned pages in calculate_psi_aligned_address()
iommu/vt-d: Limit max address mask to MAX_AGAW_PFN_WIDTH
iommu/vt-d: Refactor PCI PRI enabling/disabling callbacks
iommu/vt-d: Add helper to flush caches for context change
iommu/vt-d: Add helper to allocate paging domain
iommu/vt-d: Downgrade warning for pre-enabled IR
iommu/vt-d: Remove control over Execute-Requested requests
iommu/vt-d: Remove comment for def_domain_type
iommu/vt-d: Handle volatile descriptor status read
iommu/vt-d: Use try_cmpxchg64() in intel_pasid_get_entry()
* iommu/arm/smmu: (32 commits)
iommu: Move IOMMU_DIRTY_NO_CLEAR define
iommu/arm-smmu-qcom: Register the TBU driver in qcom_smmu_impl_init
iommu/arm-smmu-v3: Enable HTTU for stage1 with io-pgtable mapping
iommu/arm-smmu-v3: Add support for dirty tracking in domain alloc
iommu/io-pgtable-arm: Add read_and_clear_dirty() support
iommu/arm-smmu-v3: Add feature detection for HTTU
iommu/arm-smmu-v3: Add support for domain_alloc_user fn
iommu/arm-smmu-qcom: record reason for deferring probe
iommu/arm-smmu: Pretty-print context fault related regs
iommu/arm-smmu-qcom-debug: Do not print for handled faults
iommu/arm-smmu: Add CB prefix to register bitfields
dt-bindings: arm-smmu: Add X1E80100 GPU SMMU
iommu/arm-smmu-v3: add missing MODULE_DESCRIPTION() macro
iommu/arm-smmu-v3: Shrink the strtab l1_desc array
iommu/arm-smmu-v3: Do not zero the strtab twice
iommu/arm-smmu-v3: Allow setting a S1 domain to a PASID
iommu/arm-smmu-v3: Allow a PASID to be set when RID is IDENTITY/BLOCKED
iommu/arm-smmu-v3: Test the STE S1DSS functionality
iommu/arm-smmu-v3: Allow IDENTITY/BLOCKED to be set while PASID is used
iommu/arm-smmu-v3: Put the SVA mmu notifier in the smmu_domain
...
The response code from user space is only allowed to be SUCCESS or
INVALID. All other values are treated by the device as a response code of
Response Failure according to PCI spec, section 10.4.2.1. This response
disables the Page Request Interface for the Function.
Add a check in iommufd_fault_fops_write() to avoid invalid response
code.
Fixes: 07838f7fd5 ("iommufd: Add iommufd fault object")
Link: https://lore.kernel.org/r/20240710083341.44617-3-baolu.lu@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
The helper calculate_psi_aligned_address() is used to convert an arbitrary
range into a size-aligned one.
The aligned_pages variable is calculated from input start and end, but is
not adjusted when the start pfn is not aligned and the mask is adjusted,
which results in an incorrect number of pages returned.
The number of pages is used by qi_flush_piotlb() to flush caches for the
first-stage translation. With the wrong number of pages, the cache is not
synchronized, leading to inconsistencies in some cases.
Fixes: c4d27ffaa8 ("iommu/vt-d: Add cache tag invalidation helpers")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20240709152643.28109-3-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>
Address mask specifies the number of low order bits of the address field
that must be masked for the invalidation operation.
Since address bits masked start from bit 12, the max address mask should
be MAX_AGAW_PFN_WIDTH, as defined in Table 19 ("Invalidate Descriptor
Address Mask Encodings") of the spec.
Limit the max address mask returned from calculate_psi_aligned_address()
to MAX_AGAW_PFN_WIDTH to prevent potential integer overflow in the
following code:
qi_flush_dev_iotlb():
...
addr |= (1ULL << (VTD_PAGE_SHIFT + mask - 1)) - 1;
...
Fixes: c4d27ffaa8 ("iommu/vt-d: Add cache tag invalidation helpers")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20240709152643.28109-2-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>
With CONFIG_SWIOTLB_DYNAMIC enabled, each round-trip map/unmap pair
in the swiotlb results in 6 calls to swiotlb_find_pool(). In multiple
places, the pool is found and used in one function, and then must
be found again in the next function that is called because only the
tlb_addr is passed as an argument. These are the six call sites:
dma_direct_map_page:
1. swiotlb_map -> swiotlb_tbl_map_single -> swiotlb_bounce
dma_direct_unmap_page:
2. dma_direct_sync_single_for_cpu -> is_swiotlb_buffer
3. dma_direct_sync_single_for_cpu -> swiotlb_sync_single_for_cpu ->
swiotlb_bounce
4. is_swiotlb_buffer
5. swiotlb_tbl_unmap_single -> swiotlb_del_transient
6. swiotlb_tbl_unmap_single -> swiotlb_release_slots
Reduce the number of calls by finding the pool at a higher level, and
passing it as an argument instead of searching again. A key change is
for is_swiotlb_buffer() to return a pool pointer instead of a boolean,
and then pass this pool pointer to subsequent swiotlb functions.
There are 9 occurrences of is_swiotlb_buffer() used to test if a buffer
is a swiotlb buffer before calling a swiotlb function. To reduce code
duplication in getting the pool pointer and passing it as an argument,
introduce inline wrappers for this pattern. The generated code is
essentially unchanged.
Since is_swiotlb_buffer() no longer returns a boolean, rename some
functions to reflect the change:
* swiotlb_find_pool() becomes __swiotlb_find_pool()
* is_swiotlb_buffer() becomes swiotlb_find_pool()
* is_xen_swiotlb_buffer() becomes xen_swiotlb_find_pool()
With these changes, a round-trip map/unmap pair requires only 2 pool
lookups (listed using the new names and wrappers):
dma_direct_unmap_page:
1. dma_direct_sync_single_for_cpu -> swiotlb_find_pool
2. swiotlb_tbl_unmap_single -> swiotlb_find_pool
These changes come from noticing the inefficiencies in a code review,
not from performance measurements. With CONFIG_SWIOTLB_DYNAMIC,
__swiotlb_find_pool() is not trivial, and it uses an RCU read lock,
so avoiding the redundant calls helps performance in a hot path.
When CONFIG_SWIOTLB_DYNAMIC is *not* set, the code size reduction
is minimal and the perf benefits are likely negligible, but no
harm is done.
No functional change is intended.
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Petr Tesarik <petr@tesarici.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Lu Baolu says:
====================
This series implements the functionality of delivering IO page faults to
user space through the IOMMUFD framework. One feasible use case is the
nested translation. Nested translation is a hardware feature that supports
two-stage translation tables for IOMMU. The second-stage translation table
is managed by the host VMM, while the first-stage translation table is
owned by user space. This allows user space to control the IOMMU mappings
for its devices.
When an IO page fault occurs on the first-stage translation table, the
IOMMU hardware can deliver the page fault to user space through the
IOMMUFD framework. User space can then handle the page fault and respond
to the device top-down through the IOMMUFD. This allows user space to
implement its own IO page fault handling policies.
User space application that is capable of handling IO page faults should
allocate a fault object, and bind the fault object to any domain that it
is willing to handle the fault generatd for them. On a successful return
of fault object allocation, the user can retrieve and respond to page
faults by reading or writing to the file descriptor (FD) returned.
The iommu selftest framework has been updated to test the IO page fault
delivery and response functionality.
====================
* iommufd_pri:
iommufd/selftest: Add coverage for IOPF test
iommufd/selftest: Add IOPF support for mock device
iommufd: Associate fault object with iommufd_hw_pgtable
iommufd: Fault-capable hwpt attach/detach/replace
iommufd: Add iommufd fault object
iommufd: Add fault and response message definitions
iommu: Extend domain attach group with handle support
iommu: Add attach handle to struct iopf_group
iommu: Remove sva handle list
iommu: Introduce domain attachment handle
Link: https://lore.kernel.org/all/20240702063444.105814-1-baolu.lu@linux.intel.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
When allocating a user iommufd_hw_pagetable, the user space is allowed to
associate a fault object with the hw_pagetable by specifying the fault
object ID in the page table allocation data and setting the
IOMMU_HWPT_FAULT_ID_VALID flag bit.
On a successful return of hwpt allocation, the user can retrieve and
respond to page faults by reading and writing the file interface of the
fault object.
Once a fault object has been associated with a hwpt, the hwpt is
iopf-capable, indicated by hwpt->fault is non NULL. Attaching,
detaching, or replacing an iopf-capable hwpt to an RID or PASID will
differ from those that are not iopf-capable.
Link: https://lore.kernel.org/r/20240702063444.105814-9-baolu.lu@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Add iopf-capable hw page table attach/detach/replace helpers. The pointer
to iommufd_device is stored in the domain attachment handle, so that it
can be echo'ed back in the iopf_group.
The iopf-capable hw page tables can only be attached to devices that
support the IOMMU_DEV_FEAT_IOPF feature. On the first attachment of an
iopf-capable hw_pagetable to the device, the IOPF feature is enabled on
the device. Similarly, after the last iopf-capable hwpt is detached from
the device, the IOPF feature is disabled on the device.
The current implementation allows a replacement between iopf-capable and
non-iopf-capable hw page tables. This matches the nested translation use
case, where a parent domain is attached by default and can then be
replaced with a nested user domain with iopf support.
Link: https://lore.kernel.org/r/20240702063444.105814-8-baolu.lu@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
An iommufd fault object provides an interface for delivering I/O page
faults to user space. These objects are created and destroyed by user
space, and they can be associated with or dissociated from hardware page
table objects during page table allocation or destruction.
User space interacts with the fault object through a file interface. This
interface offers a straightforward and efficient way for user space to
handle page faults. It allows user space to read fault messages
sequentially and respond to them by writing to the same file. The file
interface supports reading messages in poll mode, so it's recommended that
user space applications use io_uring to enhance read and write efficiency.
A fault object can be associated with any iopf-capable iommufd_hw_pgtable
during the pgtable's allocation. All I/O page faults triggered by devices
when accessing the I/O addresses of an iommufd_hw_pgtable are routed
through the fault object to user space. Similarly, user space's responses
to these page faults are routed back to the iommu device driver through
the same fault object.
Link: https://lore.kernel.org/r/20240702063444.105814-7-baolu.lu@linux.intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
There's no real need for callers to resolve ops from a fwnode in order
to then pass both to iommu_fwspec_init() - it's simpler and more sensible
for that to resolve the ops itself. This in turn means we can centralise
the notion of checking for a present driver, and enforce that fwspecs
aren't allocated unless and until we know they will be usable.
Also use this opportunity to modernise with some "new" helpers that
arrived shortly after this code was first written; the generic
fwnode_handle_get() clears up that ugly get/put mismatch, while
of_fwnode_handle() can now abstract those open-coded dereferences.
Tested-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/0e2727adeb8cd73274425322f2f793561bdc927e.1719919669.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Commit <17de3f5fdd35> ("iommu: Retire bus ops") removes iommu ops from
bus. The iommu subsystem no longer relies on bus for operations. So the
bus parameter in iommu_domain_alloc() is no longer relevant.
Add a new interface named iommu_paging_domain_alloc(), which explicitly
indicates the allocation of a paging domain for DMA managed by a kernel
driver. The new interface takes a device pointer as its parameter, that
better aligns with the current iommu subsystem.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20240610085555.88197-2-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>
Unlike the SVA case where each PASID of a device has an SVA domain
attached to it, the I/O page faults are handled by the fault handler
of the SVA domain. The I/O page faults for a user page table might
be handled by the domain attached to RID or the domain attached to
the PASID, depending on whether the PASID table is managed by user
space or kernel. As a result, there is a need for the domain attach
group interfaces to have attach handle support. The attach handle
will be forwarded to the fault handler of the user domain.
Add some variants of the domain attaching group interfaces so that they
could support the attach handle and export them for use in IOMMUFD.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20240702063444.105814-5-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>
Previously, the domain that a page fault targets is stored in an
iopf_group, which represents a minimal set of page faults. With the
introduction of attach handle, replace the domain with the handle
so that the fault handler can obtain more information as needed
when handling the faults.
iommu_report_device_fault() is currently used for SVA page faults,
which handles the page fault in an internal cycle. The domain is retrieved
with iommu_get_domain_for_dev_pasid() if the pasid in the fault message
is valid. This doesn't work in IOMMUFD case, where if the pasid table of
a device is wholly managed by user space, there is no domain attached to
the PASID of the device, and all page faults are forwarded through a
NESTING domain attaching to RID.
Add a static flag in iommu ops, which indicates if the IOMMU driver
supports user-managed PASID tables. In the iopf deliver path, if no
attach handle found for the iopf PASID, roll back to RID domain when
the IOMMU driver supports this capability.
iommu_get_domain_for_dev_pasid() is no longer used and can be removed.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20240702063444.105814-4-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>
