- 30 Oct, 2023 4 commits
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Jason Gunthorpe authored
Patches in Joerg's iommu tree to convert the mock driver to use domain_alloc_paging() that clash badly with the way the selftest changes for nesting were structured. Massage the selftest so that it looks closer the code after the domain_alloc_paging() conversion to ease the merge. Change __mock_domain_alloc_paging() into mock_domain_alloc_paging() in the same way as the iommu tree. The merge resolution then trivially takes both and deletes mock_domain_alloc(). Link: https://lore.kernel.org/r/0-v1-90a855762c96+19de-mock_merge_jgg@nvidia.comReviewed-by:
Nicolin Chen <nicolinc@nvidia.com> Reviewed-by:
Kevin Tian <kevin.tian@intel.com> Reviewed-by:
Yi Liu <yi.l.liu@intel.com> Signed-off-by:
Jason Gunthorpe <jgg@nvidia.com>
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Joao Martins authored
iommufd_test_dirty()/IOMMU_TEST_OP_DIRTY sets the dirty bits in the mock domain implementation that the userspace side validates against what it obtains via the UAPI. However in introducing iommufd_test_dirty() it forgot to validate page_size being 0 leading to two possible divide-by-zero problems: one at the beginning when calculating @max and while calculating the IOVA in the XArray PFN tracking list. While at it, validate the length to require non-zero value as well, as we can't be allocating a 0-sized bitmap. Link: https://lore.kernel.org/r/20231030113446.7056-1-joao.m.martins@oracle.com Reported-by: syzbot+25dc7383c30ecdc83c38@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-iommu/00000000000005f6aa0608b9220f@google.com/ Fixes: a9af47e3 ("iommufd/selftest: Test IOMMU_HWPT_GET_DIRTY_BITMAP") Signed-off-by:
Joao Martins <joao.m.martins@oracle.com> Signed-off-by:
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Jason Gunthorpe authored
We never initialize the two interval tree nodes, and zero fill is not the same as RB_CLEAR_NODE. This can hide issues where we missed adding the area to the trees. Factor out the allocation and clear the two nodes. Fixes: 51fe6141 ("iommufd: Data structure to provide IOVA to PFN mapping") Link: https://lore.kernel.org/r/20231030145035.GG691768@ziepe.caSigned-off-by:
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Koichiro Den authored
In iopt_area_split(), if the original iopt_area has filled a domain and is linked to domains_itree, pages_nodes have to be properly reinserted. Otherwise the domains_itree becomes corrupted and we will UAF. Fixes: 51fe6141 ("iommufd: Data structure to provide IOVA to PFN mapping") Link: https://lore.kernel.org/r/20231027162941.2864615-2-den@valinux.co.jp Cc: stable@vger.kernel.org Signed-off-by:
Koichiro Den <den@valinux.co.jp> Signed-off-by:
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- 26 Oct, 2023 19 commits
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Lu Baolu authored
When remapping hardware is configured by system software in scalable mode as Nested (PGTT=011b) and with PWSNP field Set in the PASID-table-entry, it may Set Accessed bit and Dirty bit (and Extended Access bit if enabled) in first-stage page-table entries even when second-stage mappings indicate that corresponding first-stage page-table is Read-Only. As the result, contents of pages designated by VMM as Read-Only can be modified by IOMMU via PML5E (PML4E for 4-level tables) access as part of address translation process due to DMAs issued by Guest. This disallows read-only mappings in the domain that is supposed to be used as nested parent. Reference from Sapphire Rapids Specification Update [1], errata details, SPR17. Userspace should know this limitation by checking the IOMMU_HW_INFO_VTD_ERRATA_772415_SPR17 flag reported in the IOMMU_GET_HW_INFO ioctl. [1] https://www.intel.com/content/www/us/en/content-details/772415/content-details.html Link: https://lore.kernel.org/r/20231026044216.64964-9-yi.l.liu@intel.comReviewed-by:
Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by:
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Lu Baolu authored
This adds the support for IOMMU_HWPT_DATA_VTD_S1 type. And 'nested_parent' is added to mark the nested parent domain to sanitize the input parent domain. Link: https://lore.kernel.org/r/20231026044216.64964-8-yi.l.liu@intel.comSigned-off-by:
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Yi Liu authored
This adds the helper for setting the nested domain to a device hence enable nested domain usage on Intel VT-d. Link: https://lore.kernel.org/r/20231026044216.64964-7-yi.l.liu@intel.comSigned-off-by:
Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by:
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Yi Liu authored
This makes the helpers visible to nested.c. Link: https://lore.kernel.org/r/20231026044216.64964-6-yi.l.liu@intel.comSuggested-by:
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Lu Baolu authored
The configurations are passed in from the user when the user domain is allocated. This helper interprets these configurations according to the data structure defined in uapi/linux/iommufd.h. The EINVAL error will be returned if any of configurations are not compatible with the hardware capabilities. The caller can retry with another compatible user domain. The encoding of fields of each pasid entry is defined in section 9.6 of the VT-d spec. Link: https://lore.kernel.org/r/20231026044216.64964-5-yi.l.liu@intel.comSigned-off-by:
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Lu Baolu authored
This adds helper for accepting user parameters and allocate a nested domain. Link: https://lore.kernel.org/r/20231026044216.64964-4-yi.l.liu@intel.comReviewed-by:
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Lu Baolu authored
The nested domain fields are exclusive to those that used for a DMA remapping domain. Use union to avoid memory waste. Link: https://lore.kernel.org/r/20231026044216.64964-3-yi.l.liu@intel.comReviewed-by:
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Yi Liu authored
This adds IOMMU_HWPT_DATA_VTD_S1 for stage-1 hw_pagetable of Intel VT-d and the corressponding data structure for userspace specified parameter for the domain allocation. Link: https://lore.kernel.org/r/20231026044216.64964-2-yi.l.liu@intel.comReviewed-by:
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Yi Liu authored
This adds the scalable mode check before allocating the nested parent domain as checking nested capability is not enough. User may turn off scalable mode which also means no nested support even if the hardware supports it. Fixes: c97d1b20 ("iommu/vt-d: Add domain_alloc_user op") Link: https://lore.kernel.org/r/20231024150011.44642-1-yi.l.liu@intel.comSigned-off-by:
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Nicolin Chen authored
The IOMMU_HWPT_ALLOC ioctl now supports passing user_data to allocate a user-managed domain for nested HWPTs. Add its coverage for that. Also, update _test_cmd_hwpt_alloc() and add test_cmd/err_hwpt_alloc_nested(). Link: https://lore.kernel.org/r/20231026043938.63898-11-yi.l.liu@intel.comSigned-off-by:
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Nicolin Chen authored
Add nested domain support in the ->domain_alloc_user op with some proper sanity checks. Then, add a domain_nested_ops for all nested domains and split the get_md_pagetable helper into paging and nested helpers. Also, add an iotlb as a testing property of a nested domain. Link: https://lore.kernel.org/r/20231026043938.63898-10-yi.l.liu@intel.comSigned-off-by:
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Nicolin Chen authored
Wrap up the data type/pointer/len sanity and a copy_struct_from_user call for iommu drivers to copy driver specific data via struct iommu_user_data. And expect it to be used in the domain_alloc_user op for example. Link: https://lore.kernel.org/r/20231026043938.63898-9-yi.l.liu@intel.comSigned-off-by:
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Nicolin Chen authored
IOMMU_HWPT_ALLOC already supports iommu_domain allocation for usersapce. But it can only allocate a hw_pagetable that associates to a given IOAS, i.e. only a kernel-managed hw_pagetable of IOMMUFD_OBJ_HWPT_PAGING type. IOMMU drivers can now support user-managed hw_pagetables, for two-stage translation use cases that require user data input from the user space. Add a new IOMMUFD_OBJ_HWPT_NESTED type with its abort/destroy(). Pair it with a new iommufd_hwpt_nested structure and its to_hwpt_nested() helper. Update the to_hwpt_paging() helper, so a NESTED-type hw_pagetable can be handled in the callers, for example iommufd_hw_pagetable_enforce_rr(). Screen the inputs including the parent PAGING-type hw_pagetable that has a need of a new nest_parent flag in the iommufd_hwpt_paging structure. Extend the IOMMU_HWPT_ALLOC ioctl to accept an IOMMU driver specific data input which is tagged by the enum iommu_hwpt_data_type. Also, update the @pt_id to accept hwpt_id too besides an ioas_id. Then, use them to allocate a hw_pagetable of IOMMUFD_OBJ_HWPT_NESTED type using the iommufd_hw_pagetable_alloc_nested() allocator. Link: https://lore.kernel.org/r/20231026043938.63898-8-yi.l.liu@intel.comSigned-off-by:
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Yi Liu authored
domain_alloc_user op already accepts user flags for domain allocation, add a parent domain pointer and a driver specific user data support as well. The user data would be tagged with a type for iommu drivers to add their own driver specific user data per hw_pagetable. Add a struct iommu_user_data as a bundle of data_ptr/data_len/type from an iommufd core uAPI structure. Make the user data opaque to the core, since a userspace driver must match the kernel driver. In the future, if drivers share some common parameter, there would be a generic parameter as well. Link: https://lore.kernel.org/r/20231026043938.63898-7-yi.l.liu@intel.comSigned-off-by:
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Nicolin Chen authored
Allow iommufd_hwpt_alloc() to have a common routine but jump to different allocators corresponding to different user input pt_obj types, either an IOMMUFD_OBJ_IOAS for a PAGING hwpt or an IOMMUFD_OBJ_HWPT_PAGING as the parent for a NESTED hwpt. Also, move the "flags" validation to the hwpt allocator (paging), so that later the hwpt_nested allocator can do its own separate flags validation. Link: https://lore.kernel.org/r/20231026043938.63898-6-yi.l.liu@intel.comSigned-off-by:
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Nicolin Chen authored
To prepare for IOMMUFD_OBJ_HWPT_NESTED, derive struct iommufd_hwpt_paging from struct iommufd_hw_pagetable, by leaving the common members in struct iommufd_hw_pagetable. Add a __iommufd_object_alloc and to_hwpt_paging() helpers for the new structure. Then, update "hwpt" to "hwpt_paging" throughout the files, accordingly. Link: https://lore.kernel.org/r/20231026043938.63898-5-yi.l.liu@intel.comSuggested-by:
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Jason Gunthorpe authored
Some of the configurations during the attach/replace() should only apply to IOMMUFD_OBJ_HWPT_PAGING. Once IOMMUFD_OBJ_HWPT_NESTED gets introduced in a following patch, keeping them unconditionally in the common routine will not work. Wrap all of those PAGING-only configurations together into helpers. Do a hwpt_is_paging check whenever calling them or their fallback routines. Link: https://lore.kernel.org/r/20231026043938.63898-4-yi.l.liu@intel.comSigned-off-by:
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Jason Gunthorpe authored
To add a new IOMMUFD_OBJ_HWPT_NESTED, rename the HWPT object to confine it to PAGING hwpts/domains. The following patch will separate the hwpt structure as well. Link: https://lore.kernel.org/r/20231026043938.63898-3-yi.l.liu@intel.comSigned-off-by:
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Lu Baolu authored
Introduce a new domain type for a user I/O page table, which is nested on top of another user space address represented by a PAGING domain. This new domain can be allocated by the domain_alloc_user op, and attached to a device through the existing iommu_attach_device/group() interfaces. The mappings of a nested domain are managed by user space software, so it is not necessary to have map/unmap callbacks. Link: https://lore.kernel.org/r/20231026043938.63898-2-yi.l.liu@intel.comSigned-off-by:
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- 24 Oct, 2023 17 commits
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Nicolin Chen authored
According to the conversation in the following link: https://lore.kernel.org/linux-iommu/20231020135501.GG3952@nvidia.com/ The enforce_cache_coherency should be set/enforced in the hwpt allocation routine. The iommu driver in its attach_dev() op should decide whether to reject or not a device that doesn't match with the configuration of cache coherency. Drop the enforce_cache_coherency piece in the attach/replace() and move the remaining "num_devices" piece closer to the refcount that is using it. Accordingly drop its function prototype in the header and mark it static. Also add some extra comments to clarify the expected behaviors. Link: https://lore.kernel.org/r/20231024012958.30842-1-nicolinc@nvidia.comSuggested-by:
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Joao Martins authored
Change test_mock_dirty_bitmaps() to pass a flag where it specifies the flag under test. The test does the same thing as the GET_DIRTY_BITMAP regular test. Except that it tests whether the dirtied bits are fetched all the same a second time, as opposed to observing them cleared. Link: https://lore.kernel.org/r/20231024135109.73787-19-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Enumerate the capabilities from the mock device and test whether it advertises as expected. Include it as part of the iommufd_dirty_tracking fixture. Link: https://lore.kernel.org/r/20231024135109.73787-18-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Add a new test ioctl for simulating the dirty IOVAs in the mock domain, and implement the mock iommu domain ops that get the dirty tracking supported. The selftest exercises the usual main workflow of: 1) Setting dirty tracking from the iommu domain 2) Read and clear dirty IOPTEs Different fixtures will test different IOVA range sizes, that exercise corner cases of the bitmaps. Link: https://lore.kernel.org/r/20231024135109.73787-17-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Change mock_domain to supporting dirty tracking and add tests to exercise the new SET_DIRTY_TRACKING API in the iommufd_dirty_tracking selftest fixture. Link: https://lore.kernel.org/r/20231024135109.73787-16-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
In order to selftest the iommu domain dirty enforcing implement the mock_domain necessary support and add a new dev_flags to test that the hwpt_alloc/attach_device fails as expected. Expand the existing mock_domain fixture with a enforce_dirty test that exercises the hwpt_alloc and device attachment. Link: https://lore.kernel.org/r/20231024135109.73787-15-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Expand mock_domain test to be able to manipulate the device capabilities. This allows testing with mockdev without dirty tracking support advertised and thus make sure enforce_dirty test does the expected. To avoid breaking IOMMUFD_TEST UABI replicate the mock_domain struct and thus add an input dev_flags at the end. Link: https://lore.kernel.org/r/20231024135109.73787-14-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
IOMMU advertises Access/Dirty bits for second-stage page table if the extended capability DMAR register reports it (ECAP, mnemonic ECAP.SSADS). The first stage table is compatible with CPU page table thus A/D bits are implicitly supported. Relevant Intel IOMMU SDM ref for first stage table "3.6.2 Accessed, Extended Accessed, and Dirty Flags" and second stage table "3.7.2 Accessed and Dirty Flags". First stage page table is enabled by default so it's allowed to set dirty tracking and no control bits needed, it just returns 0. To use SSADS, set bit 9 (SSADE) in the scalable-mode PASID table entry and flush the IOTLB via pasid_flush_caches() following the manual. Relevant SDM refs: "3.7.2 Accessed and Dirty Flags" "6.5.3.3 Guidance to Software for Invalidations, Table 23. Guidance to Software for Invalidations" PTE dirty bit is located in bit 9 and it's cached in the IOTLB so flush IOTLB to make sure IOMMU attempts to set the dirty bit again. Note that iommu_dirty_bitmap_record() will add the IOVA to iotlb_gather and thus the caller of the iommu op will flush the IOTLB. Relevant manuals over the hardware translation is chapter 6 with some special mention to: "6.2.3.1 Scalable-Mode PASID-Table Entry Programming Considerations" "6.2.4 IOTLB" Select IOMMUFD_DRIVER only if IOMMUFD is enabled, given that IOMMU dirty tracking requires IOMMUFD. Link: https://lore.kernel.org/r/20231024135109.73787-13-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
IOMMU advertises Access/Dirty bits if the extended feature register reports it. Relevant AMD IOMMU SDM ref[0] "1.3.8 Enhanced Support for Access and Dirty Bits" To enable it set the DTE flag in bits 7 and 8 to enable access, or access+dirty. With that, the IOMMU starts marking the D and A flags on every Memory Request or ATS translation request. It is on the VMM side to steer whether to enable dirty tracking or not, rather than wrongly doing in IOMMU. Relevant AMD IOMMU SDM ref [0], "Table 7. Device Table Entry (DTE) Field Definitions" particularly the entry "HAD". To actually toggle on and off it's relatively simple as it's setting 2 bits on DTE and flush the device DTE cache. To get what's dirtied use existing AMD io-pgtable support, by walking the pagetables over each IOVA, with fetch_pte(). The IOTLB flushing is left to the caller (much like unmap), and iommu_dirty_bitmap_record() is the one adding page-ranges to invalidate. This allows caller to batch the flush over a big span of IOVA space, without the iommu wondering about when to flush. Worthwhile sections from AMD IOMMU SDM: "2.2.3.1 Host Access Support" "2.2.3.2 Host Dirty Support" For details on how IOMMU hardware updates the dirty bit see, and expects from its consequent clearing by CPU: "2.2.7.4 Updating Accessed and Dirty Bits in the Guest Address Tables" "2.2.7.5 Clearing Accessed and Dirty Bits" Quoting the SDM: "The setting of accessed and dirty status bits in the page tables is visible to both the CPU and the peripheral when sharing guest page tables. The IOMMU interlocked operations to update A and D bits must be 64-bit operations and naturally aligned on a 64-bit boundary" .. and for the IOMMU update sequence to Dirty bit, essentially is states: 1. Decodes the read and write intent from the memory access. 2. If P=0 in the page descriptor, fail the access. 3. Compare the A & D bits in the descriptor with the read and write intent in the request. 4. If the A or D bits need to be updated in the descriptor: * Start atomic operation. * Read the descriptor as a 64-bit access. * If the descriptor no longer appears to require an update, release the atomic lock with no further action and continue to step 5. * Calculate the new A & D bits. * Write the descriptor as a 64-bit access. * End atomic operation. 5. Continue to the next stage of translation or to the memory access. Access/Dirty bits readout also need to consider the non-default page-sizes (aka replicated PTEs as mentined by manual), as AMD supports all powers of two (except 512G) page sizes. Select IOMMUFD_DRIVER only if IOMMUFD is enabled considering that IOMMU dirty tracking requires IOMMUFD. Link: https://lore.kernel.org/r/20231024135109.73787-12-joao.m.martins@oracle.comSigned-off-by:
Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by:
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Joao Martins authored
Add the domain_alloc_user op implementation. To that end, refactor amd_iommu_domain_alloc() to receive a dev pointer and flags, while renaming it too, such that it becomes a common function shared with domain_alloc_user() implementation. The sole difference with domain_alloc_user() is that we initialize also other fields that iommu_domain_alloc() does. It lets it return the iommu domain correctly initialized in one function. This is in preparation to add dirty enforcement on AMD implementation of domain_alloc_user. Link: https://lore.kernel.org/r/20231024135109.73787-11-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
VFIO has an operation where it unmaps an IOVA while returning a bitmap with the dirty data. In reality the operation doesn't quite query the IO pagetables that the PTE was dirty or not. Instead it marks as dirty on anything that was mapped, and doing so in one syscall. In IOMMUFD the equivalent is done in two operations by querying with GET_DIRTY_IOVA followed by UNMAP_IOVA. However, this would incur two TLB flushes given that after clearing dirty bits IOMMU implementations require invalidating their IOTLB, plus another invalidation needed for the UNMAP. To allow dirty bits to be queried faster, add a flag (IOMMU_HWPT_GET_DIRTY_BITMAP_NO_CLEAR) that requests to not clear the dirty bits from the PTE (but just reading them), under the expectation that the next operation is the unmap. An alternative is to unmap and just perpectually mark as dirty as that's the same behaviour as today. So here equivalent functionally can be provided with unmap alone, and if real dirty info is required it will amortize the cost while querying. There's still a race against DMA where in theory the unmap of the IOVA (when the guest invalidates the IOTLB via emulated iommu) would race against the VF performing DMA on the same IOVA. As discussed in [0], we are accepting to resolve this race as throwing away the DMA and it doesn't matter if it hit physical DRAM or not, the VM can't tell if we threw it away because the DMA was blocked or because we failed to copy the DRAM. [0] https://lore.kernel.org/linux-iommu/20220502185239.GR8364@nvidia.com/ Link: https://lore.kernel.org/r/20231024135109.73787-10-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Extend IOMMUFD_CMD_GET_HW_INFO op to query generic iommu capabilities for a given device. Capabilities are IOMMU agnostic and use device_iommu_capable() API passing one of the IOMMU_CAP_*. Enumerate IOMMU_CAP_DIRTY_TRACKING for now in the out_capabilities field returned back to userspace. Link: https://lore.kernel.org/r/20231024135109.73787-9-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Connect a hw_pagetable to the IOMMU core dirty tracking read_and_clear_dirty iommu domain op. It exposes all of the functionality for the UAPI that read the dirtied IOVAs while clearing the Dirty bits from the PTEs. In doing so, add an IO pagetable API iopt_read_and_clear_dirty_data() that performs the reading of dirty IOPTEs for a given IOVA range and then copying back to userspace bitmap. Underneath it uses the IOMMU domain kernel API which will read the dirty bits, as well as atomically clearing the IOPTE dirty bit and flushing the IOTLB at the end. The IOVA bitmaps usage takes care of the iteration of the bitmaps user pages efficiently and without copies. Within the iterator function we iterate over io-pagetable contigous areas that have been mapped. Contrary to past incantation of a similar interface in VFIO the IOVA range to be scanned is tied in to the bitmap size, thus the application needs to pass a appropriately sized bitmap address taking into account the iova range being passed *and* page size ... as opposed to allowing bitmap-iova != iova. Link: https://lore.kernel.org/r/20231024135109.73787-8-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Every IOMMU driver should be able to implement the needed iommu domain ops to control dirty tracking. Connect a hw_pagetable to the IOMMU core dirty tracking ops, specifically the ability to enable/disable dirty tracking on an IOMMU domain (hw_pagetable id). To that end add an io_pagetable kernel API to toggle dirty tracking: * iopt_set_dirty_tracking(iopt, [domain], state) The intended caller of this is via the hw_pagetable object that is created. Internally it will ensure the leftover dirty state is cleared /right before/ dirty tracking starts. This is also useful for iommu drivers which may decide that dirty tracking is always-enabled at boot without wanting to toggle dynamically via corresponding iommu domain op. Link: https://lore.kernel.org/r/20231024135109.73787-7-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Throughout IOMMU domain lifetime that wants to use dirty tracking, some guarantees are needed such that any device attached to the iommu_domain supports dirty tracking. The idea is to handle a case where IOMMU in the system are assymetric feature-wise and thus the capability may not be supported for all devices. The enforcement is done by adding a flag into HWPT_ALLOC namely: IOMMU_HWPT_ALLOC_DIRTY_TRACKING .. Passed in HWPT_ALLOC ioctl() flags. The enforcement is done by creating a iommu_domain via domain_alloc_user() and validating the requested flags with what the device IOMMU supports (and failing accordingly) advertised). Advertising the new IOMMU domain feature flag requires that the individual iommu driver capability is supported when a future device attachment happens. Link: https://lore.kernel.org/r/20231024135109.73787-6-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Add to iommu domain operations a set of callbacks to perform dirty tracking, particulary to start and stop tracking and to read and clear the dirty data. Drivers are generally expected to dynamically change its translation structures to toggle the tracking and flush some form of control state structure that stands in the IOVA translation path. Though it's not mandatory, as drivers can also enable dirty tracking at boot, and just clear the dirty bits before setting dirty tracking. For each of the newly added IOMMU core APIs: iommu_cap::IOMMU_CAP_DIRTY_TRACKING: new device iommu_capable value when probing for capabilities of the device. .set_dirty_tracking(): an iommu driver is expected to change its translation structures and enable dirty tracking for the devices in the iommu_domain. For drivers making dirty tracking always-enabled, it should just return 0. .read_and_clear_dirty(): an iommu driver is expected to walk the pagetables for the iova range passed in and use iommu_dirty_bitmap_record() to record dirty info per IOVA. When detecting that a given IOVA is dirty it should also clear its dirty state from the PTE, *unless* the flag IOMMU_DIRTY_NO_CLEAR is passed in -- flushing is steered from the caller of the domain_op via iotlb_gather. The iommu core APIs use the same data structure in use for dirty tracking for VFIO device dirty (struct iova_bitmap) abstracted by iommu_dirty_bitmap_record() helper function. domain::dirty_ops: IOMMU domains will store the dirty ops depending on whether the iommu device supports dirty tracking or not. iommu drivers can then use this field to figure if the dirty tracking is supported+enforced on attach. The enforcement is enable via domain_alloc_user() which is done via IOMMUFD hwpt flag introduced later. Link: https://lore.kernel.org/r/20231024135109.73787-5-joao.m.martins@oracle.comSigned-off-by:
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Joao Martins authored
Have the IOVA bitmap exported symbols adhere to the IOMMUFD symbol export convention i.e. using the IOMMUFD namespace. In doing so, import the namespace in the current users. This means VFIO and the vfio-pci drivers that use iova_bitmap_set(). Link: https://lore.kernel.org/r/20231024135109.73787-4-joao.m.martins@oracle.comSuggested-by:
Brett Creeley <brett.creeley@amd.com> Reviewed-by:
Alex Williamson <alex.williamson@redhat.com> Signed-off-by:
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