Commit 94960256 authored by Wei Wang's avatar Wei Wang Committed by Dr. David Alan Gilbert
Browse files

bitmap: bitmap_count_one_with_offset 



Count the number of 1s in a bitmap starting from an offset.

Signed-off-by: default avatarWei Wang <wei.w.wang@intel.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1544516693-5395-3-git-send-email-wei.w.wang@intel.com>
Signed-off-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
parent e7c91368

include/qemu/bitmap.h

+13 −0
Original line number Diff line number Diff line
@@ -232,6 +232,19 @@ static inline long bitmap_count_one(const unsigned long *bitmap, long nbits) 
    }

}



static inline long bitmap_count_one_with_offset(const unsigned long *bitmap,

                                                long offset, long nbits)

{

    long aligned_offset = QEMU_ALIGN_DOWN(offset, BITS_PER_LONG);

    long redundant_bits = offset - aligned_offset;

    long bits_to_count = nbits + redundant_bits;

    const unsigned long *bitmap_start = bitmap +

                                        aligned_offset / BITS_PER_LONG;



    return bitmap_count_one(bitmap_start, bits_to_count) -

           bitmap_count_one(bitmap_start, redundant_bits);

}



void bitmap_set(unsigned long *map, long i, long len);

void bitmap_set_atomic(unsigned long *map, long i, long len);

void bitmap_clear(unsigned long *map, long start, long nr);