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2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman9-0/+9
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 <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-18include/linux/unaligned: force inlining of byteswap operationsDenys Vlasenko1-12/+12
Sometimes gcc mysteriously doesn't inline very small functions we expect to be inlined. See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122 With this .config: http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os, the following functions get deinlined many times. Examples of disassembly: <get_unaligned_be16> (24 copies, 108 calls): 66 8b 07 mov (%rdi),%ax 55 push %rbp 48 89 e5 mov %rsp,%rbp 86 e0 xchg %ah,%al 5d pop %rbp c3 retq <get_unaligned_be32> (25 copies, 181 calls): 8b 07 mov (%rdi),%eax 55 push %rbp 48 89 e5 mov %rsp,%rbp 0f c8 bswap %eax 5d pop %rbp c3 retq <get_unaligned_be64> (23 copies, 94 calls): 48 8b 07 mov (%rdi),%rax 55 push %rbp 48 89 e5 mov %rsp,%rbp 48 0f c8 bswap %rax 5d pop %rbp c3 retq <put_unaligned_be16> (2 copies, 11 calls): 89 f8 mov %edi,%eax 55 push %rbp c1 ef 08 shr $0x8,%edi c1 e0 08 shl $0x8,%eax 09 c7 or %eax,%edi 48 89 e5 mov %rsp,%rbp 66 89 3e mov %di,(%rsi) <put_unaligned_be32> (8 copies, 43 calls): 55 push %rbp 0f cf bswap %edi 89 3e mov %edi,(%rsi) 48 89 e5 mov %rsp,%rbp 5d pop %rbp c3 retq <put_unaligned_be64> (26 copies, 157 calls): 55 push %rbp 48 0f cf bswap %rdi 48 89 3e mov %rdi,(%rsi) 48 89 e5 mov %rsp,%rbp 5d pop %rbp c3 retq This patch fixes this via s/inline/__always_inline/. It only affects arches with efficient unaligned access insns, such as x86. (arched which lack such ops do not include linux/unaligned/access_ok.h) Code size decrease after the patch is ~8.5k: text data bss dec hex filename 92197848 20826112 36417536 149441496 8e84bd8 vmlinux 92189231 20826144 36417536 149432911 8e82a4f vmlinux6_unaligned_be_after Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Thomas Graf <tgraf@suug.ch> Cc: Peter Zijlstra <peterz@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13include/linux/unaligned/packed_struct.h: use __packedAndrew Morton1-3/+3
Cc: Will Newton <will.newton@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-23include/linux/unaligned: pack the whole struct rather than just the fieldWill Newton1-3/+3
The current packed struct implementation of unaligned access adds the packed attribute only to the field within the unaligned struct rather than to the struct as a whole. This is not sufficient to enforce proper behaviour on architectures with a default struct alignment of more than one byte. For example, the current implementation of __get_unaligned_cpu16 when compiled for arm with gcc -O1 -mstructure-size-boundary=32 assumes the struct is on a 4 byte boundary so performs the load of the 16bit packed field as if it were on a 4 byte boundary: __get_unaligned_cpu16: ldrh r0, [r0, #0] bx lr Moving the packed attribute to the struct rather than the field causes the proper unaligned access code to be generated: __get_unaligned_cpu16: ldrb r3, [r0, #0] @ zero_extendqisi2 ldrb r0, [r0, #1] @ zero_extendqisi2 orr r0, r3, r0, asl #8 bx lr Signed-off-by: Will Newton <will.newton@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24include/linux/unaligned/{l,b}e_byteshift.h: fix usage for compressed kernelsAlbin Tonnerre2-2/+2
When unaligned accesses are required for uncompressing a kernel (such as for LZO decompression on ARM in a patch that follows), including <linux/kernel.h> causes issues as it brings in a lot of things that are not available in the decompression environment. linux/kernel.h brings at least: extern int console_printk[]; extern const char hex_asc[]; which causes errors at link-time as they are not available when compiling the pre-boot environement. There are also a few others: arch/arm/boot/compressed/misc.o: In function `valid_user_regs': arch/arm/include/asm/ptrace.h:158: undefined reference to `elf_hwcap' arch/arm/boot/compressed/misc.o: In function `console_silent': include/linux/kernel.h:292: undefined reference to `console_printk' arch/arm/boot/compressed/misc.o: In function `console_verbose': include/linux/kernel.h:297: undefined reference to `console_printk' arch/arm/boot/compressed/misc.o: In function `pack_hex_byte': include/linux/kernel.h:360: undefined reference to `hex_asc' arch/arm/boot/compressed/misc.o: In function `hweight_long': include/linux/bitops.h:45: undefined reference to `hweight32' arch/arm/boot/compressed/misc.o: In function `__cmpxchg_local_generic': include/asm-generic/cmpxchg-local.h:21: undefined reference to `wrong_size_cmpxchg' include/asm-generic/cmpxchg-local.h:42: undefined reference to `wrong_size_cmpxchg' arch/arm/boot/compressed/misc.o: In function `__xchg': arch/arm/include/asm/system.h:309: undefined reference to `__bad_xchg' However, those files apparently use nothing from <linux/kernel.h>, all they need is the declaration of types such as u32 or u64, so <linux/types.h> should be enough Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Phillip Lougher <phillip@lougher.demon.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29kernel: add common infrastructure for unaligned accessHarvey Harrison10-0/+510
Create a linux/unaligned directory similar in spirit to the linux/byteorder folder to hold generic implementations collected from various arches. Currently there are five implementations: 1) packed_struct.h: C-struct based, from asm-generic/unaligned.h 2) le_byteshift.h: Open coded byte-swapping, heavily based on asm-arm 3) be_byteshift.h: Open coded byte-swapping, heavily based on asm-arm 4) memmove.h: taken from multiple implementations in tree 5) access_ok.h: taken from x86 and others, unaligned access is ok. All of the new implementations checks for sizes not equal to 1,2,4,8 and will fail to link. API additions: get_unaligned_{le16|le32|le64|be16|be32|be64}(p) which is meant to replace code of the form: le16_to_cpu(get_unaligned((__le16 *)p)); put_unaligned_{le16|le32|le64|be16|be32|be64}(val, pointer) which is meant to replace code of the form: put_unaligned(cpu_to_le16(val), (__le16 *)p); The headers that arches should include from their asm/unaligned.h: access_ok.h : Wrappers of the byteswapping functions in asm/byteorder Choose a particular implementation for little-endian access: le_byteshift.h le_memmove.h (arch must be LE) le_struct.h (arch must be LE) Choose a particular implementation for big-endian access: be_byteshift.h be_memmove.h (arch must be BE) be_struct.h (arch must be BE) After including as needed from the above, include unaligned/generic.h and define your arch's get/put_unaligned as (for LE): Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>