On Thu, Aug 02, 2018 at 10:05:28PM +0300, Nir Soffer wrote:
> File systems not supporting FALLOC_FL_ZERO_RANGE yet fall back to manual
> zeroing.
>
> We can avoid this by combining two fallocate calls:
>
>     fallocate(FALLOC_FL_PUNHCH_HOLE)

"PUNCH"

>     fallocate(0)

> +#ifdef FALLOC_FL_PUNCH_HOLE
> +  /* If we can punch hole but may not trim, we can combine punching hole and
> +      fallocate to zero a range. This is expected to be more efficient than
> +      writing zeros manually. */

Although we can fix this before pushing so there's no need to submit a
new version, it's better if the comment style sticks to the same as
used elsewhere, ie:

  /* Commmnt
   * More comment
   */