Re: [RFC PATCH v3 2/5] dma-mapping: Move encryption in __dma_direct_free_pages()

Mostafa Saleh
2026-04-17T15:07:14Z

On Wed, Apr 15, 2026 at 09:11:22PM -0300, Jason Gunthorpe wrote:
> On Wed, Apr 15, 2026 at 08:49:08PM +0000, Mostafa Saleh wrote:
> > On Fri, Apr 10, 2026 at 02:45:53PM -0300, Jason Gunthorpe wrote:
> > > On Wed, Apr 08, 2026 at 07:47:39PM +0000, Mostafa Saleh wrote:
> > > > In the next patches, we will need to avoid encrypting memory allocated
> > > > from SWIOTLB, so instead of calling dma_set_encrypted() before
> > > > __dma_direct_free_pages(), call it inside, conditional on the memory
> > > > state passed to the function.
> > > >
> > > > Signed-off-by: Mostafa Saleh <smostafa@google.com>
> > > > ---
> > > > kernel/dma/direct.c | 22 +++++++++++-----------
> > > > 1 file changed, 11 insertions(+), 11 deletions(-)
> > > >
> > > > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
> > > > index 6efb5973fbd3..ce74f213ec40 100644
> > > > --- a/kernel/dma/direct.c
> > > > +++ b/kernel/dma/direct.c
> > > > @@ -97,8 +97,11 @@ static int dma_set_encrypted(struct device *dev, void *vaddr, size_t size)
> > > > }
> > > >
> > > > static void __dma_direct_free_pages(struct device *dev, struct page *page,
> > > > - size_t size)
> > > > + size_t size, bool encrypt)
> > > > {
> > >
> > > This feels like it would be nicer if it could be the
> > > swiotlb_page_state instead of a bool, maybe the enum needs a different
> > > name.
> >
> > I am not sure I get this, at this point the swiotlb stuff is not
> > introduced yet,
>
> Just that using bool as a function argument for a flag is often
> frowned on, and you already have an enum encoding the same flag
> state.

I see, the enum is not introduced at this point, but I can change
that.

Thanks,
Mostafa

>
> Jason