1/*
2 * NUMA support for s390
3 *
4 * Implement NUMA core code.
5 *
6 * Copyright IBM Corp. 2015
7 */
8
9#define KMSG_COMPONENT "numa"
10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12#include <linux/kernel.h>
13#include <linux/mmzone.h>
14#include <linux/cpumask.h>
15#include <linux/bootmem.h>
16#include <linux/memblock.h>
17#include <linux/slab.h>
18#include <linux/node.h>
19
20#include <asm/numa.h>
21#include "numa_mode.h"
22
23pg_data_t *node_data[MAX_NUMNODES];
24EXPORT_SYMBOL(node_data);
25
26cpumask_t node_to_cpumask_map[MAX_NUMNODES];
27EXPORT_SYMBOL(node_to_cpumask_map);
28
29const struct numa_mode numa_mode_plain = {
30	.name = "plain",
31};
32
33static const struct numa_mode *mode = &numa_mode_plain;
34
35int numa_pfn_to_nid(unsigned long pfn)
36{
37	return mode->__pfn_to_nid ? mode->__pfn_to_nid(pfn) : 0;
38}
39
40void numa_update_cpu_topology(void)
41{
42	if (mode->update_cpu_topology)
43		mode->update_cpu_topology();
44}
45
46int __node_distance(int a, int b)
47{
48	return mode->distance ? mode->distance(a, b) : 0;
49}
50
51int numa_debug_enabled;
52
53/*
54 * alloc_node_data() - Allocate node data
55 */
56static __init pg_data_t *alloc_node_data(void)
57{
58	pg_data_t *res;
59
60	res = (pg_data_t *) memblock_alloc(sizeof(pg_data_t), 1);
61	if (!res)
62		panic("Could not allocate memory for node data!\n");
63	memset(res, 0, sizeof(pg_data_t));
64	return res;
65}
66
67/*
68 * numa_setup_memory() - Assign bootmem to nodes
69 *
70 * The memory is first added to memblock without any respect to nodes.
71 * This is fixed before remaining memblock memory is handed over to the
72 * buddy allocator.
73 * An important side effect is that large bootmem allocations might easily
74 * cross node boundaries, which can be needed for large allocations with
75 * smaller memory stripes in each node (i.e. when using NUMA emulation).
76 *
77 * Memory defines nodes:
78 * Therefore this routine also sets the nodes online with memory.
79 */
80static void __init numa_setup_memory(void)
81{
82	unsigned long cur_base, align, end_of_dram;
83	int nid = 0;
84
85	end_of_dram = memblock_end_of_DRAM();
86	align = mode->align ? mode->align() : ULONG_MAX;
87
88	/*
89	 * Step through all available memory and assign it to the nodes
90	 * indicated by the mode implementation.
91	 * All nodes which are seen here will be set online.
92	 */
93	cur_base = 0;
94	do {
95		nid = numa_pfn_to_nid(PFN_DOWN(cur_base));
96		node_set_online(nid);
97		memblock_set_node(cur_base, align, &memblock.memory, nid);
98		cur_base += align;
99	} while (cur_base < end_of_dram);
100
101	/* Allocate and fill out node_data */
102	for (nid = 0; nid < MAX_NUMNODES; nid++)
103		NODE_DATA(nid) = alloc_node_data();
104
105	for_each_online_node(nid) {
106		unsigned long start_pfn, end_pfn;
107		unsigned long t_start, t_end;
108		int i;
109
110		start_pfn = ULONG_MAX;
111		end_pfn = 0;
112		for_each_mem_pfn_range(i, nid, &t_start, &t_end, NULL) {
113			if (t_start < start_pfn)
114				start_pfn = t_start;
115			if (t_end > end_pfn)
116				end_pfn = t_end;
117		}
118		NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
119		NODE_DATA(nid)->node_id = nid;
120	}
121}
122
123/*
124 * numa_setup() - Earliest initialization
125 *
126 * Assign the mode and call the mode's setup routine.
127 */
128void __init numa_setup(void)
129{
130	pr_info("NUMA mode: %s\n", mode->name);
131	if (mode->setup)
132		mode->setup();
133	numa_setup_memory();
134	memblock_dump_all();
135}
136
137
138/*
139 * numa_init_early() - Initialization initcall
140 *
141 * This runs when only one CPU is online and before the first
142 * topology update is called for by the scheduler.
143 */
144static int __init numa_init_early(void)
145{
146	/* Attach all possible CPUs to node 0 for now. */
147	cpumask_copy(&node_to_cpumask_map[0], cpu_possible_mask);
148	return 0;
149}
150early_initcall(numa_init_early);
151
152/*
153 * numa_init_late() - Initialization initcall
154 *
155 * Register NUMA nodes.
156 */
157static int __init numa_init_late(void)
158{
159	int nid;
160
161	for_each_online_node(nid)
162		register_one_node(nid);
163	return 0;
164}
165device_initcall(numa_init_late);
166
167static int __init parse_debug(char *parm)
168{
169	numa_debug_enabled = 1;
170	return 0;
171}
172early_param("numa_debug", parse_debug);
173
174static int __init parse_numa(char *parm)
175{
176	if (strcmp(parm, numa_mode_plain.name) == 0)
177		mode = &numa_mode_plain;
178#ifdef CONFIG_NUMA_EMU
179	if (strcmp(parm, numa_mode_emu.name) == 0)
180		mode = &numa_mode_emu;
181#endif
182	return 0;
183}
184early_param("numa", parse_numa);
185