On Monday, 15 March 2021 6:42:45 PM AEDT Christoph Hellwig wrote:
> > +Not all devices support atomic access to system memory. To support atomic
> > +operations to a shared virtual memory page such a device needs access to
that
> > +page which is exclusive of any userspace access from the CPU. The
> +Not all devices support atomic access to system memory. To support atomic
> +operations to a shared virtual memory page such a device needs access to that
> +page which is exclusive of any userspace access from the CPU. The
> +``make_device_exclusive_range()`` function can be used to make a memo
Some devices require exclusive write access to shared virtual
memory (SVM) ranges to perform atomic operations on that memory. This
requires CPU page tables to be updated to deny access whilst atomic
operations are occurring.
In order to do this introduce a new swap entry
type (SWP_DEVICE_EXCLUSIV
