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path: root/drivers/iommu/io-pgtable-arm.c
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2016-07-01iommu/io-pgtable-arm: Fix iova_to_phys for block entriesWill Deacon
The implementation of iova_to_phys for the long-descriptor ARM io-pgtable code always masks with the granule size when inserting the low virtual address bits into the physical address determined from the page tables. In cases where the leaf entry is found before the final level of table (i.e. due to a block mapping), this results in rounding down to the bottom page of the block mapping. Consequently, the physical address range batching in the vfio_unmap_unpin is defeated and we end up taking the long way home. This patch fixes the problem by masking the virtual address with the appropriate mask for the level at which the leaf descriptor is located. The short-descriptor code already gets this right, so no change is needed there. Cc: <stable@vger.kernel.org> Reported-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-07iommu/io-pgtable-arm: Support IOMMU_MMIO flagRobin Murphy
Teach the LPAE format to create Device mappings when asked. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Eric Auger <eric.auger@linaro.org> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-02-17iommu/io-pgtable: Rationalise quirk handlingRobin Murphy
As the number of io-pgtable implementations grows beyond 1, it's time to rationalise the quirks mechanism before things have a chance to start getting really ugly and out-of-hand. To that end: - Indicate exactly which quirks each format can/does support. - Fail creating a table if a caller wants unsupported quirks. - Properly document where each quirk applies and why. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-17iommu/io-pgtable: Add helper functions for TLB opsRobin Murphy
Add some simple wrappers to avoid having the guts of the TLB operations spilled all over the page table implementations, and to provide a point to implement extra common functionality. Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-01-29iommu/io-pgtable-arm: Fix io-pgtable-arm build failureLada Trimasova
Trying to build a kernel for ARC with both options CONFIG_COMPILE_TEST and CONFIG_IOMMU_IO_PGTABLE_LPAE enabled (e.g. as a result of "make allyesconfig") results in the following build failure: | CC drivers/iommu/io-pgtable-arm.o | linux/drivers/iommu/io-pgtable-arm.c: In | function ‘__arm_lpae_alloc_pages’: | linux/drivers/iommu/io-pgtable-arm.c:221:3: | error: implicit declaration of function ‘dma_map_single’ | [-Werror=implicit-function-declaration] | dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE); | ^ | linux/drivers/iommu/io-pgtable-arm.c:221:42: | error: ‘DMA_TO_DEVICE’ undeclared (first use in this function) | dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE); | ^ Since IOMMU_IO_PGTABLE_LPAE depends on DMA API, io-pgtable-arm.c should include linux/dma-mapping.h. This fixes the reported failure. Cc: Alexey Brodkin <abrodkin@synopsys.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Joerg Roedel <joro@8bytes.org> Signed-off-by: Lada Trimasova <ltrimas@synopsys.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-12-17iommu/io-pgtable-arm: Ensure we free the final level on teardownWill Deacon
When tearing down page tables, we return early for the final level since we know that we won't have any table pointers to follow. Unfortunately, this also means that we forget to free the final level, so we end up leaking memory. Fix the issue by always freeing the current level, but just don't bother to iterate over the ptes if we're at the final level. Cc: <stable@vger.kernel.org> Reported-by: Zhang Bo <zhangbo_a@xiaomi.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17iommu/io-pgtable: Make io_pgtable_ops_to_pgtable() macro commonRobin Murphy
There is no need to keep a useful accessor for a public structure hidden away in a private implementation. Move it out alongside the structure definition so that other implementations may reuse it. Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17iommu/io-pgtable: Indicate granule for TLB maintenanceRobin Murphy
IOMMU hardware with range-based TLB maintenance commands can work happily with the iova and size arguments passed via the tlb_add_flush callback, but for IOMMUs which require separate commands per entry in the range, it is not straightforward to infer the necessary granularity when it comes to issuing the actual commands. Add an additional argument indicating the granularity for the benefit of drivers needing to know, and update the ARM LPAE code appropriately (for non-leaf invalidations we currently just assume the worst-case page granularity rather than walking the table to check). Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17iommu/io-pgtable-arm: Avoid dereferencing bogus PTEsRobin Murphy
In the case of corrupted page tables, or when an invalid size is given, __arm_lpae_unmap() may recurse beyond the maximum number of levels. Unfortunately the detection of this error condition only happens *after* calculating a nonsense offset from something which might not be a valid table pointer and dereferencing that to see if it is a valid PTE. Make things a little more robust by checking the level is valid before doing anything which depends on it being so. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-09-22iommu/io-pgtable-arm: Don't use dma_to_phys()Robin Murphy
In checking whether DMA addresses differ from physical addresses, using dma_to_phys() is actually the wrong thing to do, since it may hide any DMA offset, which is precisely one of the things we are checking for. Simply casting between the two address types, whilst ugly, is in fact the appropriate course of action. Further care (and ugliness) is also necessary in the comparison to avoid truncation if phys_addr_t and dma_addr_t differ in size. We can also reject any device with a fixed DMA offset up-front at page table creation, leaving the allocation-time check for the more subtle cases like bounce buffering due to an incorrect DMA mask. Furthermore, we can then fix the hackish KConfig dependency so that architectures without a dma_to_phys() implementation may still COMPILE_TEST (or even use!) the code. The true dependency is on the DMA API, so use the appropriate symbol for that. Signed-off-by: Robin Murphy <robin.murphy@arm.com> [will: folded in selftest fix from Yong Wu] Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-08-18iommu/io-pgtable-arm: Unmap and free table when overwriting with blockWill Deacon
When installing a block mapping, we unconditionally overwrite a non-leaf PTE if we find one. However, this can cause a problem if the following sequence of events occur: (1) iommu_map called for a 4k (i.e. PAGE_SIZE) mapping at some address - We initialise the page table all the way down to a leaf entry - No TLB maintenance is required, because we're going from invalid to valid. (2) iommu_unmap is called on the mapping installed in (1) - We walk the page table to the final (leaf) entry and zero it - We only changed a valid leaf entry, so we invalidate leaf-only (3) iommu_map is called on the same address as (1), but this time for a 2MB (i.e. BLOCK_SIZE) mapping) - We walk the page table down to the penultimate level, where we find a table entry - We overwrite the table entry with a block mapping and return without any TLB maintenance and without freeing the memory used by the now-orphaned table. This last step can lead to a walk-cache caching the overwritten table entry, causing unexpected faults when the new mapping is accessed by a device. One way to fix this would be to collapse the page table when freeing the last page at a given level, but this would require expensive iteration on every map call. Instead, this patch detects the case when we are overwriting a table entry and explicitly unmaps the table first, which takes care of both freeing and TLB invalidation. Cc: <stable@vger.kernel.org> Reported-by: Brian Starkey <brian.starkey@arm.com> Tested-by: Brian Starkey <brian.starkey@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-08-06iommu/io-pgtable: Remove flush_pgtable callbackRobin Murphy
With the users fully converted to DMA API operations, it's dead, Jim. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-08-06iommu/io-pgtable-arm: Centralise sync pointsRobin Murphy
With all current users now opted in to DMA API operations, make the iommu_dev pointer mandatory, rendering the flush_pgtable callback redundant for cache maintenance. However, since the DMA calls could be nops in the case of a coherent IOMMU, we still need to ensure the page table updates are fully synchronised against a subsequent page table walk. In the unmap path, the TLB sync will usually need to do this anyway, so just cement that requirement; in the map path which may consist solely of cacheable memory writes (in the coherent case), insert an appropriate barrier at the end of the operation, and obviate the need to call flush_pgtable on every individual update for synchronisation. Signed-off-by: Robin Murphy <robin.murphy@arm.com> [will: slight clarification to tlb_sync comment] Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-08-06iommu/io-pgtable-arm: Allow appropriate DMA API useRobin Murphy
Currently, users of the LPAE page table code are (ab)using dma_map_page() as a means to flush page table updates for non-coherent IOMMUs. Since from the CPU's point of view, creating IOMMU page tables *is* passing DMA buffers to a device (the IOMMU's page table walker), there's little reason not to use the DMA API correctly. Allow IOMMU drivers to opt into DMA API operations for page table allocation and updates by providing their appropriate device pointer. The expectation is that an LPAE IOMMU should have a full view of system memory, so use streaming mappings to avoid unnecessary pressure on ZONE_DMA, and treat any DMA translation as a warning sign. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-27iommu/io-pgtable-arm: avoid speculative walks through TTBR1Will Deacon
Although we set TCR.T1SZ to 0, the input address range covered by TTBR1 is actually calculated using T0SZ in this case on the ARM SMMU. This could theoretically lead to speculative table walks through physical address zero, leading to all sorts of fun and games if we have MMIO regions down there. This patch avoids the issue by setting EPD1 to disable walks through the unused TTBR1 register. Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-02-25iommu/io-pgtable-arm: Fix self-test WARNs on i386Will Deacon
Various build/boot bots have reported WARNs being triggered by the ARM iopgtable LPAE self-tests on i386 machines. This boils down to two instances of right-shifting a 32-bit unsigned long (i.e. an iova) by more than the size of the type. On 32-bit ARM, this happens to give us zero, hence my testing didn't catch this earlier. This patch fixes the issue by using DIV_ROUND_UP and explicit case to to avoid the erroneous shifts. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Reported-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
2015-01-19iommu: io-pgtable-arm: add non-secure quirkLaurent Pinchart
The quirk causes the Non-Secure bit to be set in all page table entries. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-19iommu: add self-consistency tests to ARM LPAE IO page table allocatorWill Deacon
This patch adds a series of basic self-consistency tests to the ARM LPAE IO page table allocator that exercise corner cases in map/unmap, as well as testing all valid configurations of pagesize, ias and stage. Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-19iommu: add ARM LPAE page table allocatorWill Deacon
A number of IOMMUs found in ARM SoCs can walk architecture-compatible page tables. This patch adds a generic allocator for Stage-1 and Stage-2 v7/v8 long-descriptor page tables. 4k, 16k and 64k pages are supported, with up to 4-levels of walk to cover a 48-bit address space. Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Will Deacon <will.deacon@arm.com>