sys/dev/drm/include/linux/bitmap.h

   1 /*
   2  * Copyright (c) 2016 François Tigeot
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice unmodified, this list of conditions, and the following
  10  *    disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #ifndef _LINUX_BITMAP_H_
  28 #define _LINUX_BITMAP_H_
  29
  30 static inline void
  31 bitmap_or(unsigned long *dst, const unsigned long *src1,
  32           const unsigned long *src2, unsigned int nbits)
  33 {
  34         if (nbits <= BITS_PER_LONG) {
  35                 *dst = *src1 | *src2;
  36         } else {
  37                 int chunks = DIV_ROUND_UP(nbits, BITS_PER_LONG);
  38
  39                 for (int i = 0;i < chunks;i++)
  40                         dst[i] = src1[i] | src2[i];
  41         }
  42 }
  43
  44 static inline int
  45 bitmap_weight(unsigned long *bitmap, unsigned int nbits)
  46 {
  47         unsigned int bit;
  48         unsigned int retval = 0;
  49
  50         for_each_set_bit(bit, bitmap, nbits)
  51                 retval++;
  52         return (retval);
  53 }
  54
  55 #endif  /* _LINUX_BITMAP_H_ */