Allocation: huge pages

Author: Gregory Price

doc/allocation/hugepages.rst

@@ -3,22 +3,28 @@
 Huge Pages
 ##########
 
-todo
-
 Contiguous Memory Allocator
 ***************************
+CXL Memory onlined as SystemRAM during early boot is eligible for use by CMA,
+as the NUMA node hosting that capacity will be `Online` at the time CMA
+carves out contiguous capacity.
 
-todo
+CXL Memory deferred to the CXL Driver for configuration cannot have its
+capacity allocated by CMA - as the NUMA node hosting the capacity is `Offline`
+at :code:`__init` time - which CMA carves out contiguous capacity.
 
 HugeTLB
 *******
-todo
 
 2MB Huge Pages
 ==============
-todo
+All CXL capacity regardless of configuration time or memory zone is eligible
+for use as 2MB huge pages.
 
 1GB Huge Pages
 ==============
+CXL capacity onlined in :code:`ZONE_NORMAL` is eligible for 1GB Gigantic Page
+allocation.
 
-todo
+CXL capacity onlined in :code:`ZONE_MOVABLE` is not eligible for 1GB Gigantic
+Page allocation.