Re: [PATCH v8 01/11] dmaengine: Add DMA_PREP_LOCK/DMA_PREP_UNLOCK flags

[Bartosz Golaszewski]

On Fri, Nov 21, 2025 at 5:36 PM Dmitry Baryshkov
<dmitry.baryshkov@xxxxxxxxxxxxxxxx> wrote:
>
> >
> > The flag has to be passed to the BAM driver at the time of calling of
> > dmaengine_prep_slave_sg() and attrs seems to be the only way with the
> > current interface. Off the top of my head: we could extend struct
> > scatterlist to allow passing some arbitrary driver data but that
> > doesn't sound like a good approach.
>
> Can we use DMA metadata in order to pass the lock / unlock flags
> instead? I might be missing something, but the LOCK / UNLOCK ops defined
> in this patchset seem to be too usecase-specific. Using metadata seems
> to allow for this kind of driver-specific sidechannel.
>

I'll look into it, thanks.

Bart