--- /dev/null
+#ifndef _LWK_BITMAP_H
+#define _LWK_BITMAP_H
+
+#ifndef __ASSEMBLY__
+
+#include <lwk/types.h>
+#include <lwk/bitops.h>
+#include <lwk/string.h>
+
+/*
+ * bitmaps provide bit arrays that consume one or more unsigned
+ * longs. The bitmap interface and available operations are listed
+ * here, in bitmap.h
+ *
+ * Function implementations generic to all architectures are in
+ * lib/bitmap.c. Functions implementations that are architecture
+ * specific are in various include/arch-<arch>/bitops.h headers
+ * and other arch/<arch> specific files.
+ *
+ * See lib/bitmap.c for more details.
+ */
+
+/*
+ * The available bitmap operations and their rough meaning in the
+ * case that the bitmap is a single unsigned long are thus:
+ *
+ * bitmap_zero(dst, nbits) *dst = 0UL
+ * bitmap_fill(dst, nbits) *dst = ~0UL
+ * bitmap_copy(dst, src, nbits) *dst = *src
+ * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2
+ * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2
+ * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2
+ * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2)
+ * bitmap_complement(dst, src, nbits) *dst = ~(*src)
+ * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal?
+ * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap?
+ * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2?
+ * bitmap_empty(src, nbits) Are all bits zero in *src?
+ * bitmap_full(src, nbits) Are all bits set in *src?
+ * bitmap_weight(src, nbits) Hamming Weight: number set bits
+ * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
+ * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
+ * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
+ * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
+ * bitmap_scnprintf(buf, len, src, nbits) Print bitmap src to buf
+ * bitmap_parse(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
+ * bitmap_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to buf
+ * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from list
+ * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
+ * bitmap_release_region(bitmap, pos, order) Free specified bit region
+ * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
+ */
+
+/*
+ * Also the following operations in asm/bitops.h apply to bitmaps.
+ *
+ * set_bit(bit, addr) *addr |= bit
+ * clear_bit(bit, addr) *addr &= ~bit
+ * change_bit(bit, addr) *addr ^= bit
+ * test_bit(bit, addr) Is bit set in *addr?
+ * test_and_set_bit(bit, addr) Set bit and return old value
+ * test_and_clear_bit(bit, addr) Clear bit and return old value
+ * test_and_change_bit(bit, addr) Change bit and return old value
+ * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
+ * find_first_bit(addr, nbits) Position first set bit in *addr
+ * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
+ * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
+ */
+
+/*
+ * The DECLARE_BITMAP(name,bits) macro, in lwk/types.h, can be used
+ * to declare an array named 'name' of just enough unsigned longs to
+ * contain all bit positions from 0 to 'bits' - 1.
+ */
+
+/*
+ * lib/bitmap.c provides these functions:
+ */
+
+extern int __bitmap_empty(const unsigned long *bitmap, int bits);
+extern int __bitmap_full(const unsigned long *bitmap, int bits);
+extern int __bitmap_equal(const unsigned long *bitmap1,
+ const unsigned long *bitmap2, int bits);
+extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
+ int bits);
+extern void __bitmap_shift_right(unsigned long *dst,
+ const unsigned long *src, int shift, int bits);
+extern void __bitmap_shift_left(unsigned long *dst,
+ const unsigned long *src, int shift, int bits);
+extern void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, int bits);
+extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, int bits);
+extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, int bits);
+extern void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, int bits);
+extern int __bitmap_intersects(const unsigned long *bitmap1,
+ const unsigned long *bitmap2, int bits);
+extern int __bitmap_subset(const unsigned long *bitmap1,
+ const unsigned long *bitmap2, int bits);
+extern int __bitmap_weight(const unsigned long *bitmap, int bits);
+
+extern int bitmap_scnprintf(char *buf, unsigned int len,
+ const unsigned long *src, int nbits);
+extern int bitmap_parse(const char __user *ubuf, unsigned int ulen,
+ unsigned long *dst, int nbits);
+extern int bitmap_scnlistprintf(char *buf, unsigned int len,
+ const unsigned long *src, int nbits);
+extern int bitmap_parselist(const char *buf, unsigned long *maskp,
+ int nmaskbits);
+extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
+ const unsigned long *old, const unsigned long *new, int bits);
+extern int bitmap_bitremap(int oldbit,
+ const unsigned long *old, const unsigned long *new, int bits);
+extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
+extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
+extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
+
+#define BITMAP_LAST_WORD_MASK(nbits) \
+( \
+ ((nbits) % BITS_PER_LONG) ? \
+ (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \
+)
+
+static inline void bitmap_zero(unsigned long *dst, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ *dst = 0UL;
+ else {
+ int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
+ memset(dst, 0, len);
+ }
+}
+
+static inline void bitmap_fill(unsigned long *dst, int nbits)
+{
+ size_t nlongs = BITS_TO_LONGS(nbits);
+ if (nlongs > 1) {
+ int len = (nlongs - 1) * sizeof(unsigned long);
+ memset(dst, 0xff, len);
+ }
+ dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits);
+}
+
+static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
+ int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ *dst = *src;
+ else {
+ int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
+ memcpy(dst, src, len);
+ }
+}
+
+static inline void bitmap_and(unsigned long *dst, const unsigned long *src1,
+ const unsigned long *src2, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ *dst = *src1 & *src2;
+ else
+ __bitmap_and(dst, src1, src2, nbits);
+}
+
+static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
+ const unsigned long *src2, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ *dst = *src1 | *src2;
+ else
+ __bitmap_or(dst, src1, src2, nbits);
+}
+
+static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
+ const unsigned long *src2, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ *dst = *src1 ^ *src2;
+ else
+ __bitmap_xor(dst, src1, src2, nbits);
+}
+
+static inline void bitmap_andnot(unsigned long *dst, const unsigned long *src1,
+ const unsigned long *src2, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ *dst = *src1 & ~(*src2);
+ else
+ __bitmap_andnot(dst, src1, src2, nbits);
+}
+
+static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
+ int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits);
+ else
+ __bitmap_complement(dst, src, nbits);
+}
+
+static inline int bitmap_equal(const unsigned long *src1,
+ const unsigned long *src2, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
+ else
+ return __bitmap_equal(src1, src2, nbits);
+}
+
+static inline int bitmap_intersects(const unsigned long *src1,
+ const unsigned long *src2, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
+ else
+ return __bitmap_intersects(src1, src2, nbits);
+}
+
+static inline int bitmap_subset(const unsigned long *src1,
+ const unsigned long *src2, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
+ else
+ return __bitmap_subset(src1, src2, nbits);
+}
+
+static inline int bitmap_empty(const unsigned long *src, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
+ else
+ return __bitmap_empty(src, nbits);
+}
+
+static inline int bitmap_full(const unsigned long *src, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
+ else
+ return __bitmap_full(src, nbits);
+}
+
+static inline int bitmap_weight(const unsigned long *src, int nbits)
+{
+ return __bitmap_weight(src, nbits);
+}
+
+static inline void bitmap_shift_right(unsigned long *dst,
+ const unsigned long *src, int n, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ *dst = *src >> n;
+ else
+ __bitmap_shift_right(dst, src, n, nbits);
+}
+
+static inline void bitmap_shift_left(unsigned long *dst,
+ const unsigned long *src, int n, int nbits)
+{
+ if (nbits <= BITS_PER_LONG)
+ *dst = (*src << n) & BITMAP_LAST_WORD_MASK(nbits);
+ else
+ __bitmap_shift_left(dst, src, n, nbits);
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _LWK_BITMAP_H */
