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
13extern 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
32extern s8 physnode_map[];
33
34static 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
43static 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 */
57