blob: 3efea7d0a351c5159d5e843406e744fe0948a33d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * This file contains NUMA specific variables and functions which can
7 * be split away from DISCONTIGMEM and are used on NUMA machines with
8 * contiguous memory.
9 *
10 * 2002/08/07 Erich Focht <efocht@ess.nec.de>
11 */
12
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/cpu.h>
14#include <linux/kernel.h>
15#include <linux/mm.h>
16#include <linux/node.h>
17#include <linux/init.h>
18#include <linux/bootmem.h>
Keith Mannthey8c2676a2006-09-30 23:27:07 -070019#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <asm/mmzone.h>
21#include <asm/numa.h>
22
23
24/*
25 * The following structures are usually initialized by ACPI or
26 * similar mechanisms and describe the NUMA characteristics of the machine.
27 */
28int num_node_memblks;
29struct node_memblk_s node_memblk[NR_NODE_MEMBLKS];
holt@sgi.com2c6e6db2008-04-03 15:17:13 -050030struct node_cpuid_s node_cpuid[NR_CPUS] =
31 { [0 ... NR_CPUS-1] = { .phys_id = 0, .nid = NUMA_NO_NODE } };
32
Linus Torvalds1da177e2005-04-16 15:20:36 -070033/*
34 * This is a matrix with "distances" between nodes, they should be
35 * proportional to the memory access latency ratios.
36 */
37u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES];
38
39/* Identify which cnode a physical address resides on */
40int
41paddr_to_nid(unsigned long paddr)
42{
43 int i;
44
45 for (i = 0; i < num_node_memblks; i++)
46 if (paddr >= node_memblk[i].start_paddr &&
47 paddr < node_memblk[i].start_paddr + node_memblk[i].size)
48 break;
49
50 return (i < num_node_memblks) ? node_memblk[i].nid : (num_node_memblks ? -1 : 0);
51}
Bob Picco2d4b1fa2005-10-04 15:13:57 -040052
53#if defined(CONFIG_SPARSEMEM) && defined(CONFIG_NUMA)
54/*
55 * Because of holes evaluate on section limits.
56 * If the section of memory exists, then return the node where the section
57 * resides. Otherwise return node 0 as the default. This is used by
58 * SPARSEMEM to allocate the SPARSEMEM sectionmap on the NUMA node where
59 * the section resides.
60 */
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -080061int __meminit __early_pfn_to_nid(unsigned long pfn)
Bob Picco2d4b1fa2005-10-04 15:13:57 -040062{
63 int i, section = pfn >> PFN_SECTION_SHIFT, ssec, esec;
64
65 for (i = 0; i < num_node_memblks; i++) {
66 ssec = node_memblk[i].start_paddr >> PA_SECTION_SHIFT;
67 esec = (node_memblk[i].start_paddr + node_memblk[i].size +
68 ((1L << PA_SECTION_SHIFT) - 1)) >> PA_SECTION_SHIFT;
69 if (section >= ssec && section < esec)
70 return node_memblk[i].nid;
71 }
72
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -080073 return -1;
Bob Picco2d4b1fa2005-10-04 15:13:57 -040074}
Keith Mannthey8c2676a2006-09-30 23:27:07 -070075
76#ifdef CONFIG_MEMORY_HOTPLUG
77/*
78 * SRAT information is stored in node_memblk[], then we can use SRAT
79 * information at memory-hot-add if necessary.
80 */
81
82int memory_add_physaddr_to_nid(u64 addr)
83{
84 int nid = paddr_to_nid(addr);
85 if (nid < 0)
86 return 0;
87 return nid;
88}
89
90EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
91#endif
Bob Picco2d4b1fa2005-10-04 15:13:57 -040092#endif