Re: [PATCH] block: save page offset gaps in cloned bio

On Wed, Aug 19, 2026 at 07:23:06AM +0200, Christoph Hellwig wrote:
> On Mon, Aug 17, 2026 at 09:59:08AM -0700, Keith Busch wrote:
> > From: Keith Busch <[email protected]>
> > 
> > The cloned bio needs to inherit the accumulated gaps between vectors so
> > that we can know if this bio can subscribe to the iova coalescing
> > optimization.
> 
> Makes sense.
> 
> > The split remainder meanwhile can reset its gaps to 0
> > since it advanced beyond it and will start accounting from there.
> 
> I don't really understand this part, though.  As in I don't even
> understand what you mean here..

The accounting for the vector gaps happens at the same time we consider
a bio for splitting. When we do split, the gap value applies only to the
front bio because that's as far as been processed. The remaining split
bio should reset its gap value to 0, and it will be recalculated when it
continues through the split consideration.