user/sven/linux.git/include/linux/bitmap.h, branch v4.14.283

bitmap: Add bitmap_alloc(), bitmap_zalloc() and bitmap_free()

2020-01-29T14:02:39Z

commit c42b65e363ce97a828f81b59033c3558f8fa7f70 upstream. A lot of code become ugly because of open coding allocations for bitmaps. Introduce three helpers to allow users be more clear of intention and keep their code neat. Note, due to multiple circular dependencies we may not provide the helpers as inliners. For now we keep them exported and, perhaps, at some point in the future we will sort out header inclusion and inheritance. Signed-off-by: Andy Shevchenko Signed-off-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman

linux/bitmap.h: fix type of nbits in bitmap_shift_right()

2019-12-01T08:13:53Z

[ Upstream commit d9873969fa8725dc6a5a21ab788c057fd8719751 ] Most other bitmap API, including the OOL version __bitmap_shift_right, take unsigned nbits. This was accidentally left out from 2fbad29917c98. Link: http://lkml.kernel.org/r/20180818131623.8755-5-linux@rasmusvillemoes.dk Fixes: 2fbad29917c98 ("lib: bitmap: change bitmap_shift_right to take unsigned parameters") Signed-off-by: Rasmus Villemoes Reported-by: Yury Norov Reviewed-by: Andy Shevchenko Cc: Rasmus Villemoes Cc: Sudeep Holla Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

linux/bitmap.h: handle constant zero-size bitmaps correctly

2019-12-01T08:13:53Z

[ Upstream commit 7275b097851a5e2e0dd4da039c7e96b59ac5314e ] The static inlines in bitmap.h do not handle a compile-time constant nbits==0 correctly (they dereference the passed src or dst pointers, despite only 0 words being valid to access). I had the 0-day buildbot chew on a patch [1] that would cause build failures for such cases without complaining, suggesting that we don't have any such users currently, at least for the 70 .config/arch combinations that was built. Should any turn up, make sure they use the out-of-line versions, which do handle nbits==0 correctly. This is of course not the most efficient, but it's much less churn than teaching all the static inlines an "if (zero_const_nbits())", and since we don't have any current instances, this doesn't affect existing code at all. [1] lkml.kernel.org/r/20180815085539.27485-1-linux@rasmusvillemoes.dk Link: http://lkml.kernel.org/r/20180818131623.8755-3-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes Reviewed-by: Andy Shevchenko Cc: Yury Norov Cc: Rasmus Villemoes Cc: Sudeep Holla Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

bitmap: fix memset optimization on big-endian systems

2018-04-08T12:26:30Z

commit 21035965f60b0502fc6537b232839389bb4ce664 upstream. Commit 2a98dc028f91 ("include/linux/bitmap.h: turn bitmap_set and bitmap_clear into memset when possible") introduced an optimization to bitmap_{set,clear}() which uses memset() when the start and length are constants aligned to a byte. This is wrong on big-endian systems; our bitmaps are arrays of unsigned long, so bit n is not at byte n / 8 in memory. This was caught by the Btrfs selftests, but the bitmap selftests also fail when run on a big-endian machine. We can still use memset if the start and length are aligned to an unsigned long, so do that on big-endian. The same problem applies to the memcmp in bitmap_equal(), so fix it there, too. Fixes: 2a98dc028f91 ("include/linux/bitmap.h: turn bitmap_set and bitmap_clear into memset when possible") Fixes: 2c6deb01525a ("bitmap: use memcmp optimisation in more situations") Cc: stable@kernel.org Reported-by: "Erhard F." Cc: Matthew Wilcox Cc: Rasmus Villemoes Cc: Andrew Morton Cc: Arnd Bergmann Signed-off-by: Omar Sandoval Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

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

2017-11-02T10:10:55Z

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

bitmap: introduce BITMAP_FROM_U64()

2017-09-09T01:26:49Z

The macro is the compile-time analogue of bitmap_from_u64() with the same purpose: convert the 64-bit number to the properly ordered pair of 32-bit parts, suitable for filling the bitmap in 32-bit BE environment. Use it to make test_bitmap_parselist() correct for 32-bit BE ABIs. Tested on BE mips/qemu. [akpm@linux-foundation.org: tweak code comment] Link: http://lkml.kernel.org/r/20170810172916.24144-1-ynorov@caviumnetworks.com Signed-off-by: Yury Norov Cc: Noam Camus Cc: Rasmus Villemoes Cc: Matthew Wilcox Cc: Mauro Carvalho Chehab Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

bitmap: use memcmp optimisation in more situations

2017-07-10T23:32:34Z

Commit 7dd968163f7c ("bitmap: bitmap_equal memcmp optimization") was rather more restrictive than necessary; we can use memcmp() to implement bitmap_equal() as long as the number of bits can be proved to be a multiple of 8. And architectures other than s390 may be able to make good use of this optimisation. [arnd@arndb.de: fix build: add a memcmp() declaration] Link: http://lkml.kernel.org/r/20170630153908.3439707-1-arnd@arndb.de Link: http://lkml.kernel.org/r/20170628153221.11322-5-willy@infradead.org Signed-off-by: Matthew Wilcox Signed-off-by: Arnd Bergmann Acked-by: Rasmus Villemoes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

include/linux/bitmap.h: turn bitmap_set and bitmap_clear into memset when possible

2017-07-10T23:32:34Z

Several callers have constant 'start' and an 'nbits' that is a multiple of 8, so we can turn them into calls to memset. We don't need the entirety of 'start' and 'nbits' to be constant, we just need to know whether they're divisible by 8. Link: http://lkml.kernel.org/r/20170628153221.11322-4-willy@infradead.org Signed-off-by: Matthew Wilcox Acked-by: Rasmus Villemoes Cc: Martin Schwidefsky Cc: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

bitmap: optimise bitmap_set and bitmap_clear of a single bit

2017-07-10T23:32:34Z

We have eight users calling bitmap_clear for a single bit and seventeen calling bitmap_set for a single bit. Rather than fix all of them to call __clear_bit or __set_bit, turn bitmap_clear and bitmap_set into inline functions and make this special case efficient. Link: http://lkml.kernel.org/r/20170628153221.11322-3-willy@infradead.org Signed-off-by: Matthew Wilcox Acked-by: Rasmus Villemoes Cc: Martin Schwidefsky Cc: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

bitmap.h, perf/core: Fix the mask in perf_output_sample_regs()

2016-08-18T08:44:20Z

When decoding the perf_regs mask in perf_output_sample_regs(), we loop through the mask using find_first_bit and find_next_bit functions. While the exisiting code works fine in most of the case, the logic is broken for big-endian 32-bit kernels. When reading a u64 mask using (u32 *)(&val)[0], find_*_bit() assumes that it gets the lower 32 bits of u64, but instead it gets the upper 32 bits - which is wrong. The fix is to swap the words of the u64 to handle this case. This is _not_ a regular endianness swap. Suggested-by: Yury Norov Signed-off-by: Madhavan Srinivasan Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Yury Norov Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Jiri Olsa Cc: Linus Torvalds Cc: Michael Ellerman Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/1471426568-31051-2-git-send-email-maddy@linux.vnet.ibm.com Signed-off-by: Ingo Molnar