dax/kmem: allow kmem to add memory with memmap_on_memory

Large amounts of memory managed by the kmem driver may come in via CXL,
and it is often desirable to have the memmap for this memory on the new
memory itself.

Enroll kmem-managed memory for memmap_on_memory semantics if the dax
region originates via CXL.  For non-CXL dax regions, retain the existing
default behavior of hot adding without memmap_on_memory semantics.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Vishal Verma <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Reviewed-by: "Huang, Ying" <[email protected]>
Tested-by: Li Zhijian <[email protected]>	[cxl.kmem and nvdimm.kmem]
Cc: Michal Hocko <[email protected]>
Cc: Oscar Salvador <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Dave Jiang <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Aneesh Kumar K.V <[email protected]>
Cc: Fan Ni <[email protected]>
Cc: Jeff Moyer <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions