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2021-06-17docs: core-api: avoid using ReST :doc:`foo` markupMauro Carvalho Chehab
The :doc:`foo` tag is auto-generated via automarkup.py. So, use the filename at the sources, instead of :doc:`foo`. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/d967d490b6655735b7df292f88859b5a1b07d0d7.1623824363.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-15dma-mapping: add a dma_alloc_noncontiguous APIChristoph Hellwig
Add a new API that returns a potentiall virtually non-contigous sg_table and a DMA address. This API is only properly implemented for dma-iommu and will simply return a contigious chunk as a fallback. The intent is that drivers can use this API if either: - no kernel mapping or only temporary kernel mappings are required. That is as a better replacement for DMA_ATTR_NO_KERNEL_MAPPING - a kernel mapping is required for cached and DMA mapped pages, but the driver also needs the pages to e.g. map them to userspace. In that sense it is a replacement for some aspects of the recently removed and never fully implemented DMA_ATTR_NON_CONSISTENT Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tomasz Figa <tfiga@chromium.org> Tested-by: Ricardo Ribalda <ribalda@chromium.org>
2021-03-15dma-mapping: add a dma_mmap_pages helperChristoph Hellwig
Add a helper to map memory allocated using dma_alloc_pages into a user address space, similar to the dma_alloc_attrs function for coherent allocations. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tomasz Figa <tfiga@chromium.org> Tested-by: Ricardo Ribalda <ribalda@chromium.org>
2021-02-09dma-mapping: remove the {alloc,free}_noncoherent methodsChristoph Hellwig
It turns out allowing non-contigous allocations here was a rather bad idea, as we'll now need to define ways to get the pages for mmaping or dma_buf sharing. Revert this change and stick to the original concept. A different API for the use case of non-contigous allocations will be added back later. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tomasz Figa <tfiga@chromium.org> Tested-by: Ricardo Ribalda <ribalda@chromium.org>:wq
2020-10-23dma-mapping: document dma_{alloc,free}_pagesChristoph Hellwig
Document the new dma_alloc_pages and dma_free_pages APIs, and fix up the documentation for dma_alloc_noncoherent and dma_free_noncoherent. Reported-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-09-25dma-mapping: add a new dma_alloc_noncoherent APIChristoph Hellwig
Add a new API to allocate and free memory that is guaranteed to be addressable by a device, but which potentially is not cache coherent for DMA. To transfer ownership to and from the device, the existing streaming DMA API calls dma_sync_single_for_device and dma_sync_single_for_cpu must be used. For now the new calls are implemented on top of dma_alloc_attrs just like the old-noncoherent API, but once all drivers are switched to the new API it will be replaced with a better working implementation that is available on all architectures. Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-11dma-mapping: move the dma_declare_coherent_memory documentationChristoph Hellwig
dma_declare_coherent_memory should not be in a DMA API guide aimed at driver writers (that is consumers of the API). Move it to a comment near the function instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-08-04Merge tag 'docs-5.9' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It's been a busy cycle for documentation - hopefully the busiest for a while to come. Changes include: - Some new Chinese translations - Progress on the battle against double words words and non-HTTPS URLs - Some block-mq documentation - More RST conversions from Mauro. At this point, that task is essentially complete, so we shouldn't see this kind of churn again for a while. Unless we decide to switch to asciidoc or something...:) - Lots of typo fixes, warning fixes, and more" * tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits) scripts/kernel-doc: optionally treat warnings as errors docs: ia64: correct typo mailmap: add entry for <alobakin@marvell.com> doc/zh_CN: add cpu-load Chinese version Documentation/admin-guide: tainted-kernels: fix spelling mistake MAINTAINERS: adjust kprobes.rst entry to new location devices.txt: document rfkill allocation PCI: correct flag name docs: filesystems: vfs: correct flag name docs: filesystems: vfs: correct sync_mode flag names docs: path-lookup: markup fixes for emphasis docs: path-lookup: more markup fixes docs: path-lookup: fix HTML entity mojibake CREDITS: Replace HTTP links with HTTPS ones docs: process: Add an example for creating a fixes tag doc/zh_CN: add Chinese translation prefer section doc/zh_CN: add clearing-warn-once Chinese version doc/zh_CN: add admin-guide index doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label futex: MAINTAINERS: Re-add selftests directory ...
2020-06-30dma-mapping: Add a new dma_need_sync APIChristoph Hellwig
Add a new API to check if calls to dma_sync_single_for_{device,cpu} are required for a given DMA streaming mapping. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200629130359.2690853-2-hch@lst.de
2020-06-26docs: fix references for DMA*.txt filesMauro Carvalho Chehab
As we moved those files to core-api, fix references to point to their newer locations. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/37b2fd159fbc7655dbf33b3eb1215396a25f6344.1592895969.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-15docs: move DMA kAPI to Documentation/core-apiMauro Carvalho Chehab
Move those files to the core-api, where they belong, renaming them to ReST and adding to the core API index file. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/a1517185418cb9d987f566ef85a5dd5c7c99f34e.1588345503.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>