Re: [RFCv1 03/72] blkmap64_ba: Add common helper for bits size calculation

[Andreas Dilger <adilger@dilger.ca>]

On Nov 7, 2022, at 06:22, Ritesh Harjani (IBM) <ritesh.list@gmail.com> wrote:
> 
> Just a quick common helper for bits size calculation.
> 
> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>

Reviewed-by: Andreas Dilger <adilger@dilger.ca>

> ---
> lib/ext2fs/blkmap64_ba.c | 20 +++++++++++++-------
> 1 file changed, 13 insertions(+), 7 deletions(-)
> 
> diff --git a/lib/ext2fs/blkmap64_ba.c b/lib/ext2fs/blkmap64_ba.c
> index 5d8f1548..4e7007f0 100644
> --- a/lib/ext2fs/blkmap64_ba.c
> +++ b/lib/ext2fs/blkmap64_ba.c
> @@ -40,6 +40,13 @@ struct ext2fs_ba_private_struct {
> 
> typedef struct ext2fs_ba_private_struct *ext2fs_ba_private;
> 
> +#define ba_bits_size(start, end) ((((end) - (start)) / 8 + 1))
> +
> +static size_t ba_bitmap_size(ext2fs_generic_bitmap_64 bitmap)
> +{
> +    return (size_t) ba_bits_size(bitmap->start, bitmap->real_end);
> +}
> +
> static errcode_t ba_alloc_private_data (ext2fs_generic_bitmap_64 bitmap)
> {
>   ext2fs_ba_private bp;
> @@ -56,7 +63,7 @@ static errcode_t ba_alloc_private_data (ext2fs_generic_bitmap_64 bitmap)
>   if (retval)
>       return retval;
> 
> -    size = (size_t) (((bitmap->real_end - bitmap->start) / 8) + 1);
> +    size = ba_bitmap_size(bitmap);
> 
>   retval = ext2fs_get_mem(size, &bp->bitarray);
>   if (retval) {
> @@ -80,7 +87,7 @@ static errcode_t ba_new_bmap(ext2_filsys fs EXT2FS_ATTR((unused)),
>       return retval;
> 
>   bp = (ext2fs_ba_private) bitmap->private;
> -    size = (size_t) (((bitmap->real_end - bitmap->start) / 8) + 1);
> +    size = ba_bitmap_size(bitmap);
>   memset(bp->bitarray, 0, size);
> 
>   return 0;
> @@ -115,7 +122,7 @@ static errcode_t ba_copy_bmap(ext2fs_generic_bitmap_64 src,
> 
>   dest_bp = (ext2fs_ba_private) dest->private;
> 
> -    size = (size_t) (((src->real_end - src->start) / 8) + 1);
> +    size = ba_bitmap_size(src);
>   memcpy (dest_bp->bitarray, src_bp->bitarray, size);
> 
>   return 0;
> @@ -145,8 +152,8 @@ static errcode_t ba_resize_bmap(ext2fs_generic_bitmap_64 bmap,
>       return 0;
>   }
> 
> -    size = ((bmap->real_end - bmap->start) / 8) + 1;
> -    new_size = ((new_real_end - bmap->start) / 8) + 1;
> +    size = ba_bitmap_size(bmap);
> +    new_size = ba_bits_size(new_real_end, bmap->start);
> 
>   if (size != new_size) {
>       retval = ext2fs_resize_mem(size, new_size, &bp->bitarray);
> @@ -306,8 +313,7 @@ static void ba_clear_bmap(ext2fs_generic_bitmap_64 bitmap)
> {
>   ext2fs_ba_private bp = (ext2fs_ba_private) bitmap->private;
> 
> -    memset(bp->bitarray, 0,
> -           (size_t) (((bitmap->real_end - bitmap->start) / 8) + 1));
> +    memset(bp->bitarray, 0, ba_bitmap_size(bitmap));
> }
> 
> #ifdef ENABLE_BMAP_STATS
> -- 
> 2.37.3