===========================
  Boot time memory management
  ===========================
  
  Early system initialization cannot use "normal" memory management
  simply because it is not set up yet. But there is still need to
  allocate memory for various data structures, for instance for the

  physical page allocator.

  A specialized allocator called ``memblock`` performs the
  boot time memory management. The architecture specific initialization
  must set it up in :c:func:`setup_arch` and tear it down in
  :c:func:`mem_init` functions.

  
  Once the early memory management is available it offers a variety of
  functions and macros for memory allocations. The allocation request
  may be directed to the first (and probably the only) node or to a
  particular node in a NUMA system. There are API variants that panic

  when an allocation fails and those that don't.

  Memblock also offers a variety of APIs that control its own behaviour.

  Memblock Overview
  =================

  
  .. kernel-doc:: mm/memblock.c
     :doc: memblock overview
  
  
  Functions and structures
  ========================

  Here is the description of memblock data structures, functions and
  macros. Some of them are actually internal, but since they are
  documented it would be silly to omit them. Besides, reading the
  descriptions for the internal functions can help to understand what
  really happens under the hood.
  
  .. kernel-doc:: include/linux/memblock.h
  .. kernel-doc:: mm/memblock.c

     :functions: