kern/bitmap: add the bitmap_for_each macro

1 files changed, 9 insertions, 0 deletions

diff --git a/kern/bitmap.h b/kern/bitmap.h
index 3663469d..fb22d69f 100644
--- a/kern/bitmap.h
+++ b/kern/bitmap.h
@@ -16,6 +16,9 @@
  *
  *
  * Arbitrary-length bit arrays.
+ *
+ * Most functions do not check whether the given parameters are valid. This
+ * is the responsibility of the caller.
  */
 
 #ifndef _KERN_BITMAP_H
@@ -156,4 +159,10 @@ bitmap_find_first(volatile unsigned long *bm, int nr_bits)
     return bitmap_find_next(bm, nr_bits, 0);
 }
 
+#define bitmap_for_each(bm, nr_bits, bit)                       \
+for ((bit) = 0;                                                 \
+     ((bit) < nr_bits)                                          \
+     && (((bit) = bitmap_find_next(bm, nr_bits, bit)) != -1);   \
+     (bit)++)
+
 #endif /* _KERN_BITMAP_H */