root/arch/x86/include/asm/mmzone_32.h

INCLUDED FROM

DEFINITIONS

1. pfn_to_nid
2. pfn_valid

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Written by Pat Gaughen (gone@us.ibm.com) Mar 2002
   4  *
   5  */
   6 
   7 #ifndef _ASM_X86_MMZONE_32_H
   8 #define _ASM_X86_MMZONE_32_H
   9 
  10 #include <asm/smp.h>
  11 
  12 #ifdef CONFIG_NUMA
  13 extern struct pglist_data *node_data[];
  14 #define NODE_DATA(nid)  (node_data[nid])
  15 #endif /* CONFIG_NUMA */
  16 
  17 #ifdef CONFIG_DISCONTIGMEM
  18 
  19 /*
  20  * generic node memory support, the following assumptions apply:
  21  *
  22  * 1) memory comes in 64Mb contiguous chunks which are either present or not
  23  * 2) we will not have more than 64Gb in total
  24  *
  25  * for now assume that 64Gb is max amount of RAM for whole system
  26  *    64Gb / 4096bytes/page = 16777216 pages
  27  */
  28 #define MAX_NR_PAGES 16777216
  29 #define MAX_SECTIONS 1024
  30 #define PAGES_PER_SECTION (MAX_NR_PAGES/MAX_SECTIONS)
  31 
  32 extern s8 physnode_map[];
  33 
  34 static inline int pfn_to_nid(unsigned long pfn)
  35 {
  36 #ifdef CONFIG_NUMA
  37         return((int) physnode_map[(pfn) / PAGES_PER_SECTION]);
  38 #else
  39         return 0;
  40 #endif
  41 }
  42 
  43 static inline int pfn_valid(int pfn)
  44 {
  45         int nid = pfn_to_nid(pfn);
  46 
  47         if (nid >= 0)
  48                 return (pfn < node_end_pfn(nid));
  49         return 0;
  50 }
  51 
  52 #define early_pfn_valid(pfn)    pfn_valid((pfn))
  53 
  54 #endif /* CONFIG_DISCONTIGMEM */
  55 
  56 #endif /* _ASM_X86_MMZONE_32_H */