mirror of
https://github.com/torvalds/linux.git
synced 2024-11-10 06:01:57 +00:00
692a68ee9c
In tools/ directory, function bitmap_clear() is currently only used in object file tools/testing/radix-tree/xarray.o. But instead of keeping a bitmap.c with only bitmap_clear() definition in radix-tree's own directory, it would be more proper to put it in common directory lib/. Sync the kernel definition and link some related libs, no functional change is expected. Signed-off-by: Wei Yang <richard.weiyang@gmail.com> CC: Matthew Wilcox <willy@infradead.org> CC: Yury Norov <yury.norov@gmail.com> Signed-off-by: Yury Norov <yury.norov@gmail.com>
123 lines
2.9 KiB
C
123 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* From lib/bitmap.c
|
|
* Helper functions for bitmap.h.
|
|
*/
|
|
#include <linux/bitmap.h>
|
|
|
|
unsigned int __bitmap_weight(const unsigned long *bitmap, int bits)
|
|
{
|
|
unsigned int k, w = 0, lim = bits/BITS_PER_LONG;
|
|
|
|
for (k = 0; k < lim; k++)
|
|
w += hweight_long(bitmap[k]);
|
|
|
|
if (bits % BITS_PER_LONG)
|
|
w += hweight_long(bitmap[k] & BITMAP_LAST_WORD_MASK(bits));
|
|
|
|
return w;
|
|
}
|
|
|
|
void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
|
|
const unsigned long *bitmap2, int bits)
|
|
{
|
|
int k;
|
|
int nr = BITS_TO_LONGS(bits);
|
|
|
|
for (k = 0; k < nr; k++)
|
|
dst[k] = bitmap1[k] | bitmap2[k];
|
|
}
|
|
|
|
size_t bitmap_scnprintf(unsigned long *bitmap, unsigned int nbits,
|
|
char *buf, size_t size)
|
|
{
|
|
/* current bit is 'cur', most recently seen range is [rbot, rtop] */
|
|
unsigned int cur, rbot, rtop;
|
|
bool first = true;
|
|
size_t ret = 0;
|
|
|
|
rbot = cur = find_first_bit(bitmap, nbits);
|
|
while (cur < nbits) {
|
|
rtop = cur;
|
|
cur = find_next_bit(bitmap, nbits, cur + 1);
|
|
if (cur < nbits && cur <= rtop + 1)
|
|
continue;
|
|
|
|
if (!first)
|
|
ret += scnprintf(buf + ret, size - ret, ",");
|
|
|
|
first = false;
|
|
|
|
ret += scnprintf(buf + ret, size - ret, "%d", rbot);
|
|
if (rbot < rtop)
|
|
ret += scnprintf(buf + ret, size - ret, "-%d", rtop);
|
|
|
|
rbot = cur;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
bool __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
|
|
const unsigned long *bitmap2, unsigned int bits)
|
|
{
|
|
unsigned int k;
|
|
unsigned int lim = bits/BITS_PER_LONG;
|
|
unsigned long result = 0;
|
|
|
|
for (k = 0; k < lim; k++)
|
|
result |= (dst[k] = bitmap1[k] & bitmap2[k]);
|
|
if (bits % BITS_PER_LONG)
|
|
result |= (dst[k] = bitmap1[k] & bitmap2[k] &
|
|
BITMAP_LAST_WORD_MASK(bits));
|
|
return result != 0;
|
|
}
|
|
|
|
bool __bitmap_equal(const unsigned long *bitmap1,
|
|
const unsigned long *bitmap2, unsigned int bits)
|
|
{
|
|
unsigned int k, lim = bits/BITS_PER_LONG;
|
|
for (k = 0; k < lim; ++k)
|
|
if (bitmap1[k] != bitmap2[k])
|
|
return false;
|
|
|
|
if (bits % BITS_PER_LONG)
|
|
if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool __bitmap_intersects(const unsigned long *bitmap1,
|
|
const unsigned long *bitmap2, unsigned int bits)
|
|
{
|
|
unsigned int k, lim = bits/BITS_PER_LONG;
|
|
for (k = 0; k < lim; ++k)
|
|
if (bitmap1[k] & bitmap2[k])
|
|
return true;
|
|
|
|
if (bits % BITS_PER_LONG)
|
|
if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
void __bitmap_clear(unsigned long *map, unsigned int start, int len)
|
|
{
|
|
unsigned long *p = map + BIT_WORD(start);
|
|
const unsigned int size = start + len;
|
|
int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
|
|
unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
|
|
|
|
while (len - bits_to_clear >= 0) {
|
|
*p &= ~mask_to_clear;
|
|
len -= bits_to_clear;
|
|
bits_to_clear = BITS_PER_LONG;
|
|
mask_to_clear = ~0UL;
|
|
p++;
|
|
}
|
|
if (len) {
|
|
mask_to_clear &= BITMAP_LAST_WORD_MASK(size);
|
|
*p &= ~mask_to_clear;
|
|
}
|
|
}
|