BMC/Intel-BMC/linux.git/lib/swiotlb.c, branch dev-4.10

swiotlb: ensure that page-sized mappings are page-aligned

2017-01-15T17:37:24+00:00

Some drivers do depend on page mappings to be page aligned. Swiotlb already enforces such alignment for mappings greater than page, extend that to page-sized mappings as well. Without this fix, nvme hits BUG() in nvme_setup_prps(), because that routine assumes page-aligned mappings. Signed-off-by: Nikita Yushchenko Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Konrad Rzeszutek Wilk

swiotlb: Export swiotlb_max_segment to users

2017-01-06T18:00:01+00:00

So they can figure out what is the optimal number of pages that can be contingously stitched together without fear of bounce buffer. We also expose an mechanism for sub-users of SWIOTLB API, such as Xen-SWIOTLB to set the max segment value. And lastly if swiotlb=force is set (which mandates we bounce buffer everything) we set max_segment so at least we can bounce buffer one 4K page instead of a giant 512KB one for which we may not have space. Signed-off-by: Konrad Rzeszutek Wilk Reported-and-Tested-by: Juergen Gross

swiotlb: Add swiotlb=noforce debug option

2016-12-19T14:05:20+00:00

On architectures like arm64, swiotlb is tied intimately to the core architecture DMA support. In addition, ZONE_DMA cannot be disabled. To aid debugging and catch devices not supporting DMA to memory outside the 32-bit address space, add a kernel command line option "swiotlb=noforce", which disables the use of bounce buffers. If specified, trying to map memory that cannot be used with DMA will fail, and a rate-limited warning will be printed. Note that io_tlb_nslabs is set to 1, which is the minimal supported value. Signed-off-by: Geert Uytterhoeven Signed-off-by: Konrad Rzeszutek Wilk

swiotlb: Convert swiotlb_force from int to enum

2016-12-19T14:05:20+00:00

Convert the flag swiotlb_force from an int to an enum, to prepare for the advent of more possible values. Suggested-by: Konrad Rzeszutek Wilk Signed-off-by: Geert Uytterhoeven Signed-off-by: Konrad Rzeszutek Wilk

swiotlb: Minor fix-ups for DMA_ATTR_SKIP_CPU_SYNC support

2016-11-10T20:56:19+00:00

I am updating the paths so that instead of trying to pass "attr | DMA_ATTR_SKIP_CPU_SYNC" we instead just OR the value into attr and then pass it since attr will not be used after we make the unmap call. I realized there was one spot I had missed when I was applying the DMA attribute to the DMA mapping exception handling. This change corrects that. Finally it looks like there is a stray blank line at the end of the swiotlb_unmap_sg_attrs function that can be dropped. Signed-off-by: Alexander Duyck Signed-off-by: Konrad Rzeszutek Wilk

swiotlb: Add support for DMA_ATTR_SKIP_CPU_SYNC

2016-11-07T20:06:33+00:00

As a first step to making DMA_ATTR_SKIP_CPU_SYNC apply to architectures beyond just ARM I need to make it so that the swiotlb will respect the flag. In order to do that I also need to update the swiotlb-xen since it heavily makes use of the functionality. Cc: Konrad Rzeszutek Wilk Signed-off-by: Alexander Duyck Signed-off-by: Konrad Rzeszutek Wilk

swiotlb: Drop unused functions swiotlb_map_sg and swiotlb_unmap_sg

2016-11-07T20:06:31+00:00

There are no users for swiotlb_map_sg or swiotlb_unmap_sg so we might as well just drop them. Signed-off-by: Alexander Duyck Acked-by: Christoph Hellwig Signed-off-by: Konrad Rzeszutek Wilk

swiotlb: Rate-limit printing when running out of SW-IOMMU space

2016-11-07T20:06:26+00:00

If the system runs out of SW-IOMMU space, changes are high successive requests will fail, too, flooding the kernel log. This is true especially for streaming DMA, which is typically used repeatedly outside the driver's initialization routine. Add rate-limiting to fix this. While at it, get rid of the open-coded dev_name() handling by using the appropriate dev_err_*() variant. Signed-off-by: Geert Uytterhoeven Signed-off-by: Konrad Rzeszutek Wilk

dma-mapping: use unsigned long for dma_attrs

2016-08-04T12:50:07+00:00

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

Merge branch 'for-4.2/sg' of git://git.kernel.dk/linux-block

2015-06-25T22:22:36+00:00

Pull asm/scatterlist.h removal from Jens Axboe: "We don't have any specific arch scatterlist anymore, since parisc finally switched over. Kill the include" * 'for-4.2/sg' of git://git.kernel.dk/linux-block: remove scatterlist.h generation from arch Kbuild files remove