bitmap_compat.h

#ifndef __SOUND_BITMAP_COMPAT_H
#define __SOUND_BITMAP_COMPAT_H

#include <linux/types.h>

#ifndef BITS_TO_LONGS
#define BITS_TO_LONGS(bits) (((bits)+BITS_PER_LONG-1)/BITS_PER_LONG)
#endif

#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 {
            int k;
            int nr = BITS_TO_LONGS(nbits);

            for (k = 0; k < nr; k++)
                  dst[k] = src1[k] & src2[k];
      }
}

#endif /* __SOUND_BITMAP_COMPAT_H */