tools: add more bitmap functions

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>

1 files changed, 26 insertions, 0 deletions

diff --git a/tools/include/linux/bitmap.h b/tools/include/linux/bitmap.h
index 43c1c5021e4b..eef41d500e9e 100644
--- a/tools/include/linux/bitmap.h
+++ b/tools/include/linux/bitmap.h
@@ -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))