linux/tools/lib/bitmap.c
Kees Cook 005f17007f bitmap: Fix return values to be unsigned
Both nodemask and bitmap routines had mixed return values that provided
potentially signed return values that could never happen. This was
leading to the compiler getting confusing about the range of possible
return values (it was thinking things could be negative where they could
not be). In preparation for fixing nodemask, fix all the bitmap routines
that should be returning unsigned (or bool) values.

Cc: Yury Norov <yury.norov@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Christophe de Dinechin <dinechin@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-06-03 06:52:58 -07:00

103 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* From lib/bitmap.c
* Helper functions for bitmap.h.
*/
#include <linux/bitmap.h>
int __bitmap_weight(const unsigned long *bitmap, int bits)
{
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;
}
int __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;
}