linux-kernel-test/arch/x86/lib/bitstr_64.c
Andrew Hastings 801916c1b3 x86: fix off-by-one in find_next_zero_string
Fix an off-by-one error in find_next_zero_string which prevents
allocating the last bit.

[ tglx: arch/x86 adaptation ]

Signed-off-by: Andrew Hastings <abh@cray.com> on behalf of Cray Inc.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-17 20:15:22 +02:00

29 lines
563 B
C

#include <linux/module.h>
#include <linux/bitops.h>
/* Find string of zero bits in a bitmap */
unsigned long
find_next_zero_string(unsigned long *bitmap, long start, long nbits, int len)
{
unsigned long n, end, i;
again:
n = find_next_zero_bit(bitmap, nbits, start);
if (n == -1)
return -1;
/* could test bitsliced, but it's hardly worth it */
end = n+len;
if (end > nbits)
return -1;
for (i = n+1; i < end; i++) {
if (test_bit(i, bitmap)) {
start = i+1;
goto again;
}
}
return n;
}
EXPORT_SYMBOL(find_next_zero_string);