bitops: move find_bit_*_le functions from le.h to find.h

It's convenient to have all find_bit declarations in one place.

Signed-off-by: Yury Norov <[email protected]>
Tested-by: Wolfram Sang <ws

bitops: move find_bit_*_le functions from le.h to find.h

It's convenient to have all find_bit declarations in one place.

Signed-off-by: Yury Norov <[email protected]>
Tested-by: Wolfram Sang <[email protected]>

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lib: add fast path for find_next_*_bit()

Similarly to bitmap functions, find_next_*_bit() users will benefit if
we'll handle a case of bitmaps that fit into a single word inline. In the
very best c

lib: add fast path for find_next_*_bit()

Similarly to bitmap functions, find_next_*_bit() users will benefit if
we'll handle a case of bitmaps that fit into a single word inline. In the
very best case, the compiler may replace a function call with a few
instructions.

This is the quite typical find_next_bit() user:

unsigned int cpumask_next(int n, const struct cpumask *srcp)
{
/* -1 is a legal arg here. */
if (n != -1)
cpumask_check(n);
return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1);
}
EXPORT_SYMBOL(cpumask_next);

Currently, on ARM64 the generated code looks like this:
0000000000000000 <cpumask_next>:
0: a9bf7bfd stp x29, x30, [sp, #-16]!
4: 11000402 add w2, w0, #0x1
8: aa0103e0 mov x0, x1
c: d2800401 mov x1, #0x40 // #64
10: 910003fd mov x29, sp
14: 93407c42 sxtw x2, w2
18: 94000000 bl 0 <find_next_bit>
1c: a8c17bfd ldp x29, x30, [sp], #16
20: d65f03c0 ret
24: d503201f nop

After applying this patch:
0000000000000140 <cpumask_next>:
140: 11000400 add w0, w0, #0x1
144: 93407c00 sxtw x0, w0
148: f100fc1f cmp x0, #0x3f
14c: 54000168 b.hi 178 <cpumask_next+0x38> // b.pmore
150: f9400023 ldr x3, [x1]
154: 92800001 mov x1, #0xffffffffffffffff // #-1
158: 9ac02020 lsl x0, x1, x0
15c: 52800802 mov w2, #0x40 // #64
160: 8a030001 and x1, x0, x3
164: dac00020 rbit x0, x1
168: f100003f cmp x1, #0x0
16c: dac01000 clz x0, x0
170: 1a800040 csel w0, w2, w0, eq // eq = none
174: d65f03c0 ret
178: 52800800 mov w0, #0x40 // #64
17c: d65f03c0 ret

find_next_bit() call is replaced with 6 instructions. find_next_bit()
itself is 41 instructions plus function call overhead.

Despite inlining, the scripts/bloat-o-meter report smaller .text size
after applying the series:
add/remove: 11/9 grow/shrink: 233/176 up/down: 5780/-6768 (-988)

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Yury Norov <[email protected]>
Acked-by: Rasmus Villemoes <[email protected]>
Acked-by: Andy Shevchenko <[email protected]>
Cc: Alexey Klimov <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: David Sterba <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Jianpeng Ma <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: John Paul Adrian Glaubitz <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Rich Felker <[email protected]>
Cc: Stefano Brivio <[email protected]>
Cc: Wei Yang <[email protected]>
Cc: Wolfram Sang <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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lib: inline _find_next_bit() wrappers

lib/find_bit.c declares five single-line wrappers for _find_next_bit().
We may turn those wrappers to inline functions. It eliminates unneeded
function calls a

lib: inline _find_next_bit() wrappers

lib/find_bit.c declares five single-line wrappers for _find_next_bit().
We may turn those wrappers to inline functions. It eliminates unneeded
function calls and opens room for compile-time optimizations.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Yury Norov <[email protected]>
Acked-by: Rasmus Villemoes <[email protected]>
Acked-by: Andy Shevchenko <[email protected]>
Cc: Alexey Klimov <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: David Sterba <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Jianpeng Ma <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: John Paul Adrian Glaubitz <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Rich Felker <[email protected]>
Cc: Stefano Brivio <[email protected]>
Cc: Wei Yang <[email protected]>
Cc: Wolfram Sang <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

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

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 <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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bitops: introduce generic {clear,set}_bit_le()

Needed to replace test_and_set_bit_le() in virt/kvm/kvm_main.c which is
being used for this missing function.

Signed-off-by: Takuya Yoshikawa <yoshika

bitops: introduce generic {clear,set}_bit_le()

Needed to replace test_and_set_bit_le() in virt/kvm/kvm_main.c which is
being used for this missing function.

Signed-off-by: Takuya Yoshikawa <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Cc: Marcelo Tosatti <[email protected]>
Cc: Avi Kivity <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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bitops: add #ifndef for each of find bitops

The style that we normally use in asm-generic is to test the macro itself
for existence, so in asm-generic, do:

#ifndef find_next_zero_bit_le
extern un

bitops: add #ifndef for each of find bitops

The style that we normally use in asm-generic is to test the macro itself
for existence, so in asm-generic, do:

#ifndef find_next_zero_bit_le
extern unsigned long find_next_zero_bit_le(const void *addr,
unsigned long size, unsigned long offset);
#endif

and in the architectures, write

static inline unsigned long find_next_zero_bit_le(const void *addr,
unsigned long size, unsigned long offset)
#define find_next_zero_bit_le find_next_zero_bit_le

This adds the #ifndef for each of the find bitops in the generic header
and source files.

Suggested-by: Arnd Bergmann <[email protected]>
Signed-off-by: Akinobu Mita <[email protected]>
Acked-by: Russell King <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Greg Ungerer <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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asm-generic: change little-endian bitops to take any pointer types

This makes the little-endian bitops take any pointer types by changing the
prototypes and adding casts in the preprocessor macros.

asm-generic: change little-endian bitops to take any pointer types

This makes the little-endian bitops take any pointer types by changing the
prototypes and adding casts in the preprocessor macros.

That would seem to at least make all the filesystem code happier, and they
can continue to do just something like

#define ext2_set_bit __test_and_set_bit_le

(or whatever the exact sequence ends up being).

Signed-off-by: Akinobu Mita <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Richard Henderson <[email protected]>
Cc: Ivan Kokshaysky <[email protected]>
Cc: Mikael Starvik <[email protected]>
Cc: David Howells <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Cc: "Luck, Tony" <[email protected]>
Cc: Ralf Baechle <[email protected]>
Cc: Kyle McMartin <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Grant Grundler <[email protected]>
Cc: Paul Mundt <[email protected]>
Cc: Kazumoto Kojima <[email protected]>
Cc: Hirokazu Takata <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Chris Zankel <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Hans-Christian Egtvedt <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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asm-generic: rename generic little-endian bitops functions

As a preparation for providing little-endian bitops for all architectures,
This renames generic implementation of little-endian bitops. (r

asm-generic: rename generic little-endian bitops functions

As a preparation for providing little-endian bitops for all architectures,
This renames generic implementation of little-endian bitops. (remove
"generic_" prefix and postfix "_le")

s/generic_find_next_le_bit/find_next_bit_le/
s/generic_find_next_zero_le_bit/find_next_zero_bit_le/
s/generic_find_first_zero_le_bit/find_first_zero_bit_le/
s/generic___test_and_set_le_bit/__test_and_set_bit_le/
s/generic___test_and_clear_le_bit/__test_and_clear_bit_le/
s/generic_test_le_bit/test_bit_le/
s/generic___set_le_bit/__set_bit_le/
s/generic___clear_le_bit/__clear_bit_le/
s/generic_test_and_set_le_bit/test_and_set_bit_le/
s/generic_test_and_clear_le_bit/test_and_clear_bit_le/

Signed-off-by: Akinobu Mita <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Acked-by: Hans-Christian Egtvedt <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Roman Zippel <[email protected]>
Cc: Andreas Schwab <[email protected]>
Cc: Greg Ungerer <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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bitops: merge little and big endian definisions in asm-generic/bitops/le.h

This patch series introduces little-endian bit operations in asm/bitops.h
for all architectures and converts all ext2 non-a

bitops: merge little and big endian definisions in asm-generic/bitops/le.h

This patch series introduces little-endian bit operations in asm/bitops.h
for all architectures and converts all ext2 non-atomic and minix bit
operations to use little-endian bit operations. It enables us to remove
ext2 non-atomic and minix bit operations from asm/bitops.h. The reason
they should be removed from asm/bitops.h is as follows:

For ext2 non-atomic bit operations, they are used for little-endian byte
order bitmap access by some filesystems and modules. But using ext2_*()
functions on a module other than ext2 filesystem makes some feel strange.

For minix bit operations, they are only used by minix filesystem and are
useless by other modules. Because byte order of inode and block bitmap is

This patch:

In order to make the forthcoming changes smaller, this merges macro
definisions in asm-generic/bitops/le.h for big-endian and little-endian as
much as possible.

This also removes unused BITOP_WORD macro.

Signed-off-by: Akinobu Mita <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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ext4: Add ext4_find_next_bit()

This function is used by the ext4 multi block allocator patches.

Also add generic_find_next_le_bit

Signed-off-by: Aneesh Kumar K.V <[email protected]>

ext4: Add ext4_find_next_bit()

This function is used by the ext4 multi block allocator patches.

Also add generic_find_next_le_bit

Signed-off-by: Aneesh Kumar K.V <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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[PATCH] bitops: generic ext2_{set,clear,test,find_first_zero,find_next_zero}_bit()

This patch introduces the C-language equivalents of the functions below:

int ext2_set_bit(int nr, volatile unsigne

[PATCH] bitops: generic ext2_{set,clear,test,find_first_zero,find_next_zero}_bit()

This patch introduces the C-language equivalents of the functions below:

int ext2_set_bit(int nr, volatile unsigned long *addr);
int ext2_clear_bit(int nr, volatile unsigned long *addr);
int ext2_test_bit(int nr, const volatile unsigned long *addr);
unsigned long ext2_find_first_zero_bit(const unsigned long *addr,
unsigned long size);
unsinged long ext2_find_next_zero_bit(const unsigned long *addr,
unsigned long size);

In include/asm-generic/bitops/ext2-non-atomic.h

This code largely copied from:

include/asm-powerpc/bitops.h
include/asm-parisc/bitops.h

Signed-off-by: Akinobu Mita <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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