[PATCH 08/29] tools: Add more bitmap functions

From: Matthew Wilcox
Date: Wed Nov 16 2016 - 17:30:34 EST


From: Matthew Wilcox <willy@xxxxxxxxxxxxxxx>

I need the following functions for the radix tree:

bitmap_fill
find_next_zero_bit
bitmap_empty
bitmap_full

Copy the implementations from include/linux/bitmap.h and lib/find_bit.c
---
tools/include/linux/bitmap.h | 26 ++++++++++++++++++++++++++
tools/lib/find_bit.c | 8 ++++++++
2 files changed, 34 insertions(+)

diff --git a/tools/include/linux/bitmap.h b/tools/include/linux/bitmap.h
index 43c1c50..eef41d5 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))
diff --git a/tools/lib/find_bit.c b/tools/lib/find_bit.c
index 9122a9e..de26b6f 100644
--- a/tools/lib/find_bit.c
+++ b/tools/lib/find_bit.c
@@ -66,6 +66,14 @@ unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
}
#endif

+#ifndef find_next_zero_bit
+unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
+ unsigned long offset)
+{
+ return _find_next_bit(addr, size, offset, ~0UL);
+}
+#endif
+
#ifndef find_first_bit
/*
* Find the first set bit in a memory region.
--
2.10.2