Re: [PATCH v21 1/5] xbitmap: Introduce xbitmap

[Matthew Wilcox]

On Fri, Feb 16, 2018 at 07:44:50PM +0200, Andy Shevchenko wrote:
> On Tue, Jan 9, 2018 at 1:10 PM, Wei Wang <wei.w.wang@xxxxxxxxx> wrote:
> > From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
> >
> > The eXtensible Bitmap is a sparse bitmap representation which is
> > efficient for set bits which tend to cluster. It supports up to
> > 'unsigned long' worth of bits.
> 
> >  lib/xbitmap.c                            | 444 +++++++++++++++++++++++++++++++
> 
> Please, split tests to a separate module.

Hah, I just did this two days ago!  I didn't publish it yet, but I also made
it compile both in userspace and as a kernel module.  

It's the top two commits here:

http://git.infradead.org/users/willy/linux-dax.git/shortlog/refs/heads/xarray-2018-02-12

Note this is a complete rewrite compared to the version presented here; it
sits on top of the XArray and no longer has a preload interface.  It has a
superset of the IDA functionality.