a saner API for allocating DMA addressable pages · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 02/28] drm/exynos: stop setting DMA_ATTR_NON_CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 12/28] dma-direct: remove dma_direct_{alloc,free}_pages · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 06/28] lib82596: move DMA allocation into the callers of i82596_probe · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 06/28] lib82596: move DMA allocation into the callers of i82596_probe · Thomas Bogendoerfer <tsbogend@alpha.franken.de> · 2020-09-01
[PATCH 17/28] dma-mapping: move dma_common_{mmap,get_sgtable} out of mapping.c · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 09/28] MIPS/jazzdma: remove the unused vdma_remap function · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 09/28] MIPS/jazzdma: remove the unused vdma_remap function · Thomas Bogendoerfer <tsbogend@alpha.franken.de> · 2020-09-01
[PATCH 26/28] dmapool: add dma_alloc_pages support · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 18/28] dma-mapping: move the dma_declare_coherent_memory documentation · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 23/28] lib82596: convert from dma_cache_sync to dma_sync_single_for_device · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 24/28] 53c700: convert from dma_cache_sync to dma_sync_single_for_device · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 28/28] nvme-pci: use dma_alloc_pages backed dmapools · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 27/28] nvme-pci: fix PRP pool size · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 25/28] dma-mapping: remove dma_cache_sync · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 19/28] dma-mapping: replace DMA_ATTR_NON_CONSISTENT with dma_{alloc,free}_pages · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 19/28] dma-mapping: replace DMA_ATTR_NON_CONSISTENT with dma_{alloc, free}_pages · Tomasz Figa <tfiga@chromium.org> · 2020-08-19
Re: [PATCH 19/28] dma-mapping: replace DMA_ATTR_NON_CONSISTENT with dma_{alloc, free}_pages · Christoph Hellwig <hch@lst.de> · 2020-08-20
[PATCH 20/28] sgiwd93: convert from dma_cache_sync to dma_sync_single_for_device · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 21/28] hal2: convert from dma_cache_sync to dma_sync_single_for_device · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device · Thomas Bogendoerfer <tsbogend@alpha.franken.de> · 2020-09-01
Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device · Thomas Bogendoerfer <tsbogend@alpha.franken.de> · 2020-09-01
Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device · Christoph Hellwig <hch@lst.de> · 2020-09-01
Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device · Thomas Bogendoerfer <tsbogend@alpha.franken.de> · 2020-09-01
Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device · Thomas Bogendoerfer <tsbogend@alpha.franken.de> · 2020-09-02
Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device · Christoph Hellwig <hch@lst.de> · 2020-09-03
Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device · Christoph Hellwig <hch@lst.de> · 2020-09-03
Re: [PATCH 22/28] sgiseeq: convert from dma_cache_sync to dma_sync_single_for_device · Christoph Hellwig <hch@lst.de> · 2020-09-03
[PATCH 16/28] dma-direct: rename and cleanup __phys_to_dma · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 15/28] dma-direct: remove __dma_to_phys · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 14/28] dma-direct: use phys_to_dma_direct in dma_direct_alloc · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 08/28] MIPS: make dma_sync_*_for_cpu a little less overzealous · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 08/28] MIPS: make dma_sync_*_for_cpu a little less overzealous · Thomas Bogendoerfer <tsbogend@alpha.franken.de> · 2020-09-01
[PATCH 11/28] dma-mapping: add (back) arch_dma_mark_clean for ia64 · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 13/28] dma-direct: lift gfp_t manipulation out of__dma_direct_alloc_pages · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 07/28] 53c700: improve non-coherent DMA handling · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 07/28] 53c700: improve non-coherent DMA handling · James Bottomley <James.Bottomley@HansenPartnership.com> · 2020-09-01
Re: [PATCH 07/28] 53c700: improve non-coherent DMA handling · Matthew Wilcox <willy@infradead.org> · 2020-09-01
Re: [PATCH 07/28] 53c700: improve non-coherent DMA handling · James Bottomley <James.Bottomley@HansenPartnership.com> · 2020-09-01
Re: [PATCH 07/28] 53c700: improve non-coherent DMA handling · Helge Deller <deller@gmx.de> · 2020-09-01
Re: [PATCH 07/28] 53c700: improve non-coherent DMA handling · Helge Deller <deller@gmx.de> · 2020-09-01
Re: [PATCH 07/28] 53c700: improve non-coherent DMA handling · Matthew Wilcox <willy@infradead.org> · 2020-09-01
Re: [PATCH 07/28] 53c700: improve non-coherent DMA handling · Helge Deller <deller@gmx.de> · 2020-09-02
[PATCH 10/28] MIPS/jazzdma: decouple from dma-direct · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 10/28] MIPS/jazzdma: decouple from dma-direct · Thomas Bogendoerfer <tsbogend@alpha.franken.de> · 2020-09-01
[PATCH 04/28] net/au1000-eth: stop using DMA_ATTR_NON_CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 03/28] drm/nouveau/gk20a: stop setting DMA_ATTR_NON_CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-19
[PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Robin Murphy <robin.murphy@arm.com> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Robin Murphy <robin.murphy@arm.com> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-19
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-08-20
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Christoph Hellwig <hch@lst.de> · 2020-09-01
Re: [PATCH 05/28] media/v4l2: remove V4L2-FLAG-MEMORY-NON-CONSISTENT · Tomasz Figa <tfiga@chromium.org> · 2020-09-01
[PATCH 01/28] mm: turn alloc_pages into an inline function · Christoph Hellwig <hch@lst.de> · 2020-08-19
Re: a saner API for allocating DMA addressable pages · Marek Szyprowski <m.szyprowski@samsung.com> · 2020-08-25
Re: a saner API for allocating DMA addressable pages · Christoph Hellwig <hch@lst.de> · 2020-08-25
Re: a saner API for allocating DMA addressable pages · Helge Deller <deller@gmx.de> · 2020-08-29

Re: a saner API for allocating DMA addressable pages

From: Christoph Hellwig <hch@lst.de>
Date: 2020-08-25 13:26:28
Also in: alsa-devel, linux-arm-kernel, linux-doc, linux-iommu, linux-media, linux-mips, linux-mm, linux-nvme, linux-samsung-soc, linux-scsi, lkml, nouveau

On Tue, Aug 25, 2020 at 01:30:41PM +0200, Marek Szyprowski wrote:

I really wonder what is the difference between this new API and 
alloc_pages(GFP_DMA, n). Is this API really needed? I thought that this 
is legacy thing to be removed one day...

The difference is that the pages returned are guranteed to be addressable
by the devie.  This is a very important difference that matters for
a lot of use cases.

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