tools: add more bitmap functions
authorMatthew Wilcox <willy@linux.intel.com>
Wed, 14 Dec 2016 23:08:26 +0000 (15:08 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 15 Dec 2016 00:04:10 +0000 (16:04 -0800)
I need the following functions for the radix tree:

  bitmap_fill
  bitmap_empty
  bitmap_full

Copy the implementations from include/linux/bitmap.h

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tools/include/linux/bitmap.h

index 43c1c50..eef41d5 100644 (file)
@@ -35,6 +35,32 @@ static inline void bitmap_zero(unsigned long *dst, int nbits)
        }
 }
 
+static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
+{
+       unsigned int nlongs = BITS_TO_LONGS(nbits);
+       if (!small_const_nbits(nbits)) {
+               unsigned int len = (nlongs - 1) * sizeof(unsigned long);
+               memset(dst, 0xff,  len);
+       }
+       dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
+}
+
+static inline int bitmap_empty(const unsigned long *src, unsigned nbits)
+{
+       if (small_const_nbits(nbits))
+               return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
+
+       return find_first_bit(src, nbits) == nbits;
+}
+
+static inline int bitmap_full(const unsigned long *src, unsigned int nbits)
+{
+       if (small_const_nbits(nbits))
+               return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
+
+       return find_first_zero_bit(src, nbits) == nbits;
+}
+
 static inline int bitmap_weight(const unsigned long *src, int nbits)
 {
        if (small_const_nbits(nbits))