[dm-devel] [RFC PATCH V2 06/13] block: add new field into 'struct bvec_iter'

[Ming Lei]

On Fri, Mar 19, 2021 at 01:44:22PM -0400, Mike Snitzer wrote:
> On Thu, Mar 18 2021 at 12:48pm -0400,
> Ming Lei <ming.lei at redhat.com> wrote:
> 
> > There is a hole at the end of 'struct bvec_iter', so put a new field
> > here and we can save cookie returned from submit_bio() here for
> > supporting bio based polling.
> > 
> > This way can avoid to extend bio unnecessarily.
> > 
> > Signed-off-by: Ming Lei <ming.lei at redhat.com>
> > ---
> >  include/linux/bvec.h | 9 +++++++++
> >  1 file changed, 9 insertions(+)
> > 
> > diff --git a/include/linux/bvec.h b/include/linux/bvec.h
> > index ff832e698efb..61c0f55f7165 100644
> > --- a/include/linux/bvec.h
> > +++ b/include/linux/bvec.h
> > @@ -43,6 +43,15 @@ struct bvec_iter {
> >  
> >  	unsigned int            bi_bvec_done;	/* number of bytes completed in
> >  						   current bvec */
> > +
> > +	/*
> > +	 * There is a hole at the end of bvec_iter, define one filed to
> 
> s/filed/field/
> 
> > +	 * hold something which isn't relate with 'bvec_iter', so that we can
> 
> s/relate/related/
> or
> s/isn't relate with/doesn't relate to/
> 
> > +	 * avoid to extend bio. So far this new field is used for bio based
> 
> s/to extend/extending/
> 
> > +	 * pooling, we will store returning value of underlying queue's
> 
> s/pooling/polling/
> 

Good catch, will fix all in V3.

-- 
Ming