kernel/git/next/linux-next.git/drivers/base/dma-coherent.c, branch master

dma-mapping: move all DMA mapping code to kernel/dma

2018-06-14T06:50:37+00:00

Currently the code is split over various files with dma- prefixes in the lib/ and drives/base directories, and the number of files keeps growing. Move them into a single directory to keep the code together and remove the file name prefixes. To match the irq infrastructure this directory is placed under the kernel/ directory. Signed-off-by: Christoph Hellwig

dma-coherent: clarify dma_mmap_from_dev_coherent documentation

2018-04-23T12:44:17+00:00

The use of "correctly mapped" here is misleading, since it can give the wrong expectation in the case that the memory *should* have been mapped from the per-device pool, but doing so failed for other reasons. Signed-off-by: Robin Murphy Signed-off-by: Christoph Hellwig

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55+00:00

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

dma-coherent: fix rmem_dma_device_init regression

2017-09-17T15:20:02+00:00

My recent bug fix introduced another bug, which caused rmem_dma_device_init to always fail, as rmem->priv is never set to anything. This restores the previous behavior, calling dma_init_coherent_memory() whenever ->priv is NULL. Fixes: d35b0996fef3 ("dma-coherent: fix dma_declare_coherent_memory() logic error") Reported-by: Roy Pledge Tested-by: Roy Pledge Signed-off-by: Arnd Bergmann Signed-off-by: Christoph Hellwig

dma-coherent: fix dma_declare_coherent_memory() logic error

2017-09-05T11:23:11+00:00

A recent change interprets the return code of dma_init_coherent_memory as an error value, but it is instead a boolean, where 'true' indicates success. This leads causes the caller to always do the wrong thing, and also triggers a compile-time warning about it: drivers/base/dma-coherent.c: In function 'dma_declare_coherent_memory': drivers/base/dma-coherent.c:99:15: error: 'mem' may be used uninitialized in this function [-Werror=maybe-uninitialized] I ended up changing the code a little more, to give use the usual error handling, as this seemed the best way to fix up the warning and make the code look reasonable at the same time. Fixes: 2436bdcda53f ("dma-coherent: remove the DMA_MEMORY_MAP and DMA_MEMORY_IO flags") Signed-off-by: Arnd Bergmann Signed-off-by: Christoph Hellwig

dma-coherent: remove an unused variable

2017-09-04T06:29:48+00:00

Signed-off-by: Christoph Hellwig Reported-by: Stephen Rothwell

dma-coherent: remove the DMA_MEMORY_MAP and DMA_MEMORY_IO flags

2017-09-01T09:59:17+00:00

DMA_MEMORY_IO was never used in the tree, so remove it. That means there is no need for the DMA_MEMORY_MAP flag either now, so remove it as well and change dma_declare_coherent_memory to return a normal errno value. Signed-off-by: Christoph Hellwig Reviewed-by: Marek Szyprowski

dma-coherent: remove the DMA_MEMORY_INCLUDES_CHILDREN flag

2017-09-01T07:50:39+00:00

This flag was never implemented or used. Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy

dma-coherent: introduce interface for default DMA pool

2017-07-20T14:09:10+00:00

Christoph noticed [1] that default DMA pool in current form overload the DMA coherent infrastructure. In reply, Robin suggested [2] to split the per-device vs. global pool interfaces, so allocation/release from default DMA pool is driven by dma ops implementation. This patch implements Robin's idea and provide interface to allocate/release/mmap the default (aka global) DMA pool. To make it clear that existing *_from_coherent routines work on per-device pool rename them to *_from_dev_coherent. [1] https://lkml.org/lkml/2017/7/7/370 [2] https://lkml.org/lkml/2017/7/7/431 Cc: Vineet Gupta Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Ralf Baechle Suggested-by: Robin Murphy Tested-by: Andras Szemzo Reviewed-by: Robin Murphy Signed-off-by: Vladimir Murzin Signed-off-by: Christoph Hellwig

drivers: dma-coherent: Introduce default DMA pool

2017-06-28T13:55:03+00:00

This patch introduces default coherent DMA pool similar to default CMA area concept. To keep other users safe code kept under CONFIG_ARM. Cc: Michal Nazarewicz Cc: Marek Szyprowski Cc: Rob Herring Cc: Mark Rutland Cc: Greg Kroah-Hartman Suggested-by: Robin Murphy Tested-by: Benjamin Gaignard Tested-by: Andras Szemzo Tested-by: Alexandre TORGUE Signed-off-by: Vladimir Murzin Signed-off-by: Christoph Hellwig