kernel.git/arch/powerpc/kernel/iommu.c, branch linux-4.17.y

powerpc/iommu: Use permission-specific DEVICE_ATTR variants

2017-09-01T06:42:54Z

Use DEVICE_ATTR_RW for read-write attributes. This simplifies the source code, improves readbility, and reduces the chance of inconsistencies. Signed-off-by: Julia Lawall Acked-by: Michael Ellerman (powerpc) Signed-off-by: Michael Ellerman

powerpc/iommu: Avoid undefined right shift in iommu_range_alloc()

2017-08-15T10:30:58Z

In iommu_range_alloc() we generate a mask by right shifting ~0, however if the specified alignment is 0 then we right shift by 64, which is undefined. UBSAN tells us so: UBSAN: Undefined behaviour in ../arch/powerpc/kernel/iommu.c:193:35 shift exponent 64 is too large for 64-bit type 'long unsigned int' We can avoid it by instead generating the mask with: align_mask = (1ull << align_order) - 1; That will also generate an undefined shift if align_order is 64 or greater, but that shouldn't be a problem for a while. Signed-off-by: Michael Ellerman

powerpc/kernel: Avoid preemption check in iommu_range_alloc()

2017-08-01T11:49:23Z

Replace the __this_cpu_read() with raw_cpu_read() in iommu_range_alloc(). Otherwise we get a warning about using __this_cpu_read() in preemptible code: BUG: using __this_cpu_read() in preemptible caller is iommu_range_alloc+0xa8/0x3d0 Preemption doesn't need to be disabled since according to the comment any CPU can safely use any IOMMU pool. Signed-off-by: Victor Aoqui Signed-off-by: Michael Ellerman

powerpc: implement ->mapping_error

2017-06-28T13:54:33Z

DMA_ERROR_CODE is going to go away, so don't rely on it. Instead define a ->mapping_error method for all IOMMU based dma operation instances. The direct ops don't ever return an error and don't need a ->mapping_error method. Signed-off-by: Christoph Hellwig Acked-by: Michael Ellerman

KVM: PPC: iommu: Unify TCE checking

2017-04-20T01:39:21Z

This reworks helpers for checking TCE update parameters in way they can be used in KVM. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Acked-by: Michael Ellerman Signed-off-by: Paul Mackerras

powerpc/vfio_spapr_tce: Add reference counting to iommu_table

2017-03-30T10:42:11Z

So far iommu_table obejcts were only used in virtual mode and had a single owner. We are going to change this by implementing in-kernel acceleration of DMA mapping requests. The proposed acceleration will handle requests in real mode and KVM will keep references to tables. This adds a kref to iommu_table and defines new helpers to update it. This replaces iommu_free_table() with iommu_tce_table_put() and makes iommu_free_table() static. iommu_tce_table_get() is not used in this patch but it will be in the following patch. Since this touches prototypes, this also removes @node_name parameter as it has never been really useful on powernv and carrying it for the pseries platform code to iommu_free_table() seems to be quite useless as well. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Acked-by: Alex Williamson Signed-off-by: Michael Ellerman

powerpc/iommu/vfio_spapr_tce: Cleanup iommu_table disposal

2017-03-30T10:42:11Z

At the moment iommu_table can be disposed by either calling iommu_table_free() directly or it_ops::free(); the only implementation of free() is in IODA2 - pnv_ioda2_table_free() - and it calls iommu_table_free() anyway. As we are going to have reference counting on tables, we need an unified way of disposing tables. This moves it_ops::free() call into iommu_free_table() and makes use of the latter. The free() callback now handles only platform-specific data. As from now on the iommu_free_table() calls it_ops->free(), we need to have it_ops initialized before calling iommu_free_table() so this moves this initialization in pnv_pci_ioda2_create_table(). This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Acked-by: Alex Williamson Signed-off-by: Michael Ellerman

powerpc/powernv/iommu: Add real mode version of iommu_table_ops::exchange()

2017-03-30T10:42:01Z

In real mode, TCE tables are invalidated using special cache-inhibited store instructions which are not available in virtual mode This defines and implements exchange_rm() callback. This does not define set_rm/clear_rm/flush_rm callbacks as there is no user for those - exchange/exchange_rm are only to be used by KVM for VFIO. The exchange_rm callback is defined for IODA1/IODA2 powernv platforms. This replaces list_for_each_entry_rcu with its lockless version as from now on pnv_pci_ioda2_tce_invalidate() can be called in the real mode too. Signed-off-by: Alexey Kardashevskiy Reviewed-by: David Gibson Signed-off-by: Michael Ellerman

powerpc: implement the DMA_ATTR_NO_WARN attribute

2016-10-11T22:06:32Z

Add support for the DMA_ATTR_NO_WARN attribute on powerpc iommu code. Link: http://lkml.kernel.org/r/1470092390-25451-3-git-send-email-mauricfo@linux.vnet.ibm.com Signed-off-by: Mauricio Faria de Oliveira Acked-by: Michael Ellerman Cc: Keith Busch Cc: Jens Axboe Cc: Benjamin Herrenschmidt Cc: Krzysztof Kozlowski Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dma-mapping: use unsigned long for dma_attrs

2016-08-04T12:50:07Z

The dma-mapping core and the implementations do not change the DMA attributes passed by pointer. Thus the pointer can point to const data. However the attributes do not have to be a bitfield. Instead unsigned long will do fine: 1. This is just simpler. Both in terms of reading the code and setting attributes. Instead of initializing local attributes on the stack and passing pointer to it to dma_set_attr(), just set the bits. 2. It brings safeness and checking for const correctness because the attributes are passed by value. Semantic patches for this change (at least most of them): virtual patch virtual context @r@ identifier f, attrs; @@ f(..., - struct dma_attrs *attrs + unsigned long attrs , ...) { ... } @@ identifier r.f; @@ f(..., - NULL + 0 ) and // Options: --all-includes virtual patch virtual context @r@ identifier f, attrs; type t; @@ t f(..., struct dma_attrs *attrs); @@ identifier r.f; @@ f(..., - NULL + 0 ) Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com Signed-off-by: Krzysztof Kozlowski Acked-by: Vineet Gupta Acked-by: Robin Murphy Acked-by: Hans-Christian Noren Egtvedt Acked-by: Mark Salter [c6x] Acked-by: Jesper Nilsson [cris] Acked-by: Daniel Vetter [drm] Reviewed-by: Bart Van Assche Acked-by: Joerg Roedel [iommu] Acked-by: Fabien Dessenne [bdisp] Reviewed-by: Marek Szyprowski [vb2-core] Acked-by: David Vrabel [xen] Acked-by: Konrad Rzeszutek Wilk [xen swiotlb] Acked-by: Joerg Roedel [iommu] Acked-by: Richard Kuo [hexagon] Acked-by: Geert Uytterhoeven [m68k] Acked-by: Gerald Schaefer [s390] Acked-by: Bjorn Andersson Acked-by: Hans-Christian Noren Egtvedt [avr32] Acked-by: Vineet Gupta [arc] Acked-by: Robin Murphy [arm64 and dma-iommu] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds