On Sun, 13 Apr 2025 17:52:15 -0500 Ira Weiny <ira.we...@intel.com> wrote:
> Dynamic Capacity CXL regions must allow memory to be added or removed > dynamically. In addition to the quantity of memory available the > location of the memory within a DC partition is dynamic based on the > extents offered by a device. CXL DAX regions must accommodate the > sparseness of this memory in the management of DAX regions and devices. > > Introduce the concept of a sparse DAX region. Introduce > create_dynamic_ram_a_region() sysfs entry to create such regions. > Special case dynamic capable regions to create a 0 sized seed DAX device > to maintain compatibility which requires a default DAX device to hold a > region reference. > > Indicate 0 byte available capacity until such time that capacity is > added. > > Sparse regions complicate the range mapping of dax devices. There is no > known use case for range mapping on sparse regions. Avoid the > complication by preventing range mapping of dax devices on sparse > regions. > > Interleaving is deferred for now. Add checks. > > Based on an original patch by Navneet Singh. > > Signed-off-by: Ira Weiny <ira.we...@intel.com> > I'm not that familiar with the DAX parts but looks fine to me. Reviewed-by: Jonathan Cameron <jonathan.came...@huawei.com>
