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Diffstat (limited to 'arch/x86_64/lib/bitstr_64.c')
-rw-r--r--arch/x86_64/lib/bitstr_64.c28
1 files changed, 28 insertions, 0 deletions
diff --git a/arch/x86_64/lib/bitstr_64.c b/arch/x86_64/lib/bitstr_64.c
new file mode 100644
index 000000000000..24676609a6ac
--- /dev/null
+++ b/arch/x86_64/lib/bitstr_64.c
@@ -0,0 +1,28 @@
+#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);