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authorYury Norov <yury.norov@gmail.com>2015-04-16 12:43:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-17 09:03:54 -0400
commit840620a1596a90636a44d6a593db4041bb28d52e (patch)
tree645de249bbe1a7994149210bdc9853d7d8143fea /lib/find_next_bit.c
parent8f6f19dd5143aa59139deeb885a8ed5e2d937e21 (diff)
lib: rename lib/find_next_bit.c to lib/find_bit.c
This file contains implementation for all find_*_bit{,_le} So giving it more generic name looks reasonable. Signed-off-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: George Spelvin <linux@horizon.com> Cc: Alexey Klimov <klimov.linux@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Daniel Borkmann <dborkman@redhat.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Mark Salter <msalter@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Thomas Graf <tgraf@suug.ch> Cc: Valentin Rothberg <valentinrothberg@gmail.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/find_next_bit.c')
-rw-r--r--lib/find_next_bit.c193
1 files changed, 0 insertions, 193 deletions
diff --git a/lib/find_next_bit.c b/lib/find_next_bit.c
deleted file mode 100644
index 18072ea9c20e..000000000000
--- a/lib/find_next_bit.c
+++ /dev/null
@@ -1,193 +0,0 @@
-/* bit search implementation
- *
- * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * Copyright (C) 2008 IBM Corporation
- * 'find_last_bit' is written by Rusty Russell <rusty@rustcorp.com.au>
- * (Inspired by David Howell's find_next_bit implementation)
- *
- * Rewritten by Yury Norov <yury.norov@gmail.com> to decrease
- * size and improve performance, 2015.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <linux/bitops.h>
-#include <linux/bitmap.h>
-#include <linux/export.h>
-#include <linux/kernel.h>
-
-#if !defined(find_next_bit) || !defined(find_next_zero_bit)
-
-/*
- * This is a common helper function for find_next_bit and
- * find_next_zero_bit. The difference is the "invert" argument, which
- * is XORed with each fetched word before searching it for one bits.
- */
-static unsigned long _find_next_bit(const unsigned long *addr,
- unsigned long nbits, unsigned long start, unsigned long invert)
-{
- unsigned long tmp;
-
- if (!nbits || start >= nbits)
- return nbits;
-
- tmp = addr[start / BITS_PER_LONG] ^ invert;
-
- /* Handle 1st word. */
- tmp &= BITMAP_FIRST_WORD_MASK(start);
- start = round_down(start, BITS_PER_LONG);
-
- while (!tmp) {
- start += BITS_PER_LONG;
- if (start >= nbits)
- return nbits;
-
- tmp = addr[start / BITS_PER_LONG] ^ invert;
- }
-
- return min(start + __ffs(tmp), nbits);
-}
-#endif
-
-#ifndef find_next_bit
-/*
- * Find the next set bit in a memory region.
- */
-unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
- unsigned long offset)
-{
- return _find_next_bit(addr, size, offset, 0UL);
-}
-EXPORT_SYMBOL(find_next_bit);
-#endif
-
-#ifndef find_next_zero_bit
-unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
- unsigned long offset)
-{
- return _find_next_bit(addr, size, offset, ~0UL);
-}
-EXPORT_SYMBOL(find_next_zero_bit);
-#endif
-
-#ifndef find_first_bit
-/*
- * Find the first set bit in a memory region.
- */
-unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
-{
- unsigned long idx;
-
- for (idx = 0; idx * BITS_PER_LONG < size; idx++) {
- if (addr[idx])
- return min(idx * BITS_PER_LONG + __ffs(addr[idx]), size);
- }
-
- return size;
-}
-EXPORT_SYMBOL(find_first_bit);
-#endif
-
-#ifndef find_first_zero_bit
-/*
- * Find the first cleared bit in a memory region.
- */
-unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size)
-{
- unsigned long idx;
-
- for (idx = 0; idx * BITS_PER_LONG < size; idx++) {
- if (addr[idx] != ~0UL)
- return min(idx * BITS_PER_LONG + ffz(addr[idx]), size);
- }
-
- return size;
-}
-EXPORT_SYMBOL(find_first_zero_bit);
-#endif
-
-#ifndef find_last_bit
-unsigned long find_last_bit(const unsigned long *addr, unsigned long size)
-{
- if (size) {
- unsigned long val = BITMAP_LAST_WORD_MASK(size);
- unsigned long idx = (size-1) / BITS_PER_LONG;
-
- do {
- val &= addr[idx];
- if (val)
- return idx * BITS_PER_LONG + __fls(val);
-
- val = ~0ul;
- } while (idx--);
- }
- return size;
-}
-EXPORT_SYMBOL(find_last_bit);
-#endif
-
-#ifdef __BIG_ENDIAN
-
-/* include/linux/byteorder does not support "unsigned long" type */
-static inline unsigned long ext2_swab(const unsigned long y)
-{
-#if BITS_PER_LONG == 64
- return (unsigned long) __swab64((u64) y);
-#elif BITS_PER_LONG == 32
- return (unsigned long) __swab32((u32) y);
-#else
-#error BITS_PER_LONG not defined
-#endif
-}
-
-#if !defined(find_next_bit_le) || !defined(find_next_zero_bit_le)
-static unsigned long _find_next_bit_le(const unsigned long *addr,
- unsigned long nbits, unsigned long start, unsigned long invert)
-{
- unsigned long tmp;
-
- if (!nbits || start >= nbits)
- return nbits;
-
- tmp = addr[start / BITS_PER_LONG] ^ invert;
-
- /* Handle 1st word. */
- tmp &= ext2_swab(BITMAP_FIRST_WORD_MASK(start));
- start = round_down(start, BITS_PER_LONG);
-
- while (!tmp) {
- start += BITS_PER_LONG;
- if (start >= nbits)
- return nbits;
-
- tmp = addr[start / BITS_PER_LONG] ^ invert;
- }
-
- return min(start + __ffs(ext2_swab(tmp)), nbits);
-}
-#endif
-
-#ifndef find_next_zero_bit_le
-unsigned long find_next_zero_bit_le(const void *addr, unsigned
- long size, unsigned long offset)
-{
- return _find_next_bit_le(addr, size, offset, ~0UL);
-}
-EXPORT_SYMBOL(find_next_zero_bit_le);
-#endif
-
-#ifndef find_next_bit_le
-unsigned long find_next_bit_le(const void *addr, unsigned
- long size, unsigned long offset)
-{
- return _find_next_bit_le(addr, size, offset, 0UL);
-}
-EXPORT_SYMBOL(find_next_bit_le);
-#endif
-
-#endif /* __BIG_ENDIAN */