1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * NUMA support for s390
  4 *
  5 * Implement NUMA core code.
  6 *
  7 * Copyright IBM Corp. 2015
  8 */
  9
 10#define KMSG_COMPONENT "numa"
 11#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 12
 13#include <linux/kernel.h>
 14#include <linux/mmzone.h>
 15#include <linux/cpumask.h>
 16#include <linux/bootmem.h>
 17#include <linux/memblock.h>
 18#include <linux/slab.h>
 19#include <linux/node.h>
 20
 21#include <asm/numa.h>
 22#include "numa_mode.h"
 23
 24pg_data_t *node_data[MAX_NUMNODES];
 25EXPORT_SYMBOL(node_data);
 26
 27cpumask_t node_to_cpumask_map[MAX_NUMNODES];
 28EXPORT_SYMBOL(node_to_cpumask_map);
 29
 30static void plain_setup(void)
 31{
 32	node_set(0, node_possible_map);
 33}
 34
 35const struct numa_mode numa_mode_plain = {
 36	.name = "plain",
 37	.setup = plain_setup,
 38};
 39
 40static const struct numa_mode *mode = &numa_mode_plain;
 41
 42int numa_pfn_to_nid(unsigned long pfn)
 43{
 44	return mode->__pfn_to_nid ? mode->__pfn_to_nid(pfn) : 0;
 45}
 46
 47void numa_update_cpu_topology(void)
 48{
 49	if (mode->update_cpu_topology)
 50		mode->update_cpu_topology();
 51}
 52
 53int __node_distance(int a, int b)
 54{
 55	return mode->distance ? mode->distance(a, b) : 0;
 56}
 57
 58int numa_debug_enabled;
 59
 60/*
 61 * alloc_node_data() - Allocate node data
 62 */
 63static __init pg_data_t *alloc_node_data(void)
 64{
 65	pg_data_t *res;
 66
 67	res = (pg_data_t *) memblock_alloc(sizeof(pg_data_t), 8);
 68	memset(res, 0, sizeof(pg_data_t));
 69	return res;
 70}
 71
 72/*
 73 * numa_setup_memory() - Assign bootmem to nodes
 74 *
 75 * The memory is first added to memblock without any respect to nodes.
 76 * This is fixed before remaining memblock memory is handed over to the
 77 * buddy allocator.
 78 * An important side effect is that large bootmem allocations might easily
 79 * cross node boundaries, which can be needed for large allocations with
 80 * smaller memory stripes in each node (i.e. when using NUMA emulation).
 81 *
 82 * Memory defines nodes:
 83 * Therefore this routine also sets the nodes online with memory.
 84 */
 85static void __init numa_setup_memory(void)
 86{
 87	unsigned long cur_base, align, end_of_dram;
 88	int nid = 0;
 89
 90	end_of_dram = memblock_end_of_DRAM();
 91	align = mode->align ? mode->align() : ULONG_MAX;
 92
 93	/*
 94	 * Step through all available memory and assign it to the nodes
 95	 * indicated by the mode implementation.
 96	 * All nodes which are seen here will be set online.
 97	 */
 98	cur_base = 0;
 99	do {
100		nid = numa_pfn_to_nid(PFN_DOWN(cur_base));
101		node_set_online(nid);
102		memblock_set_node(cur_base, align, &memblock.memory, nid);
103		cur_base += align;
104	} while (cur_base < end_of_dram);
105
106	/* Allocate and fill out node_data */
107	for (nid = 0; nid < MAX_NUMNODES; nid++)
108		NODE_DATA(nid) = alloc_node_data();
109
110	for_each_online_node(nid) {
111		unsigned long start_pfn, end_pfn;
112		unsigned long t_start, t_end;
113		int i;
114
115		start_pfn = ULONG_MAX;
116		end_pfn = 0;
117		for_each_mem_pfn_range(i, nid, &t_start, &t_end, NULL) {
118			if (t_start < start_pfn)
119				start_pfn = t_start;
120			if (t_end > end_pfn)
121				end_pfn = t_end;
122		}
123		NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
124		NODE_DATA(nid)->node_id = nid;
125	}
126}
127
128/*
129 * numa_setup() - Earliest initialization
130 *
131 * Assign the mode and call the mode's setup routine.
132 */
133void __init numa_setup(void)
134{
135	pr_info("NUMA mode: %s\n", mode->name);
136	nodes_clear(node_possible_map);
137	if (mode->setup)
138		mode->setup();
139	numa_setup_memory();
140	memblock_dump_all();
141}
142
143/*
144 * numa_init_early() - Initialization initcall
145 *
146 * This runs when only one CPU is online and before the first
147 * topology update is called for by the scheduler.
148 */
149static int __init numa_init_early(void)
150{
151	/* Attach all possible CPUs to node 0 for now. */
152	cpumask_copy(&node_to_cpumask_map[0], cpu_possible_mask);
153	return 0;
154}
155early_initcall(numa_init_early);
156
157/*
158 * numa_init_late() - Initialization initcall
159 *
160 * Register NUMA nodes.
161 */
162static int __init numa_init_late(void)
163{
164	int nid;
165
166	for_each_online_node(nid)
167		register_one_node(nid);
168	return 0;
169}
170arch_initcall(numa_init_late);
171
172static int __init parse_debug(char *parm)
173{
174	numa_debug_enabled = 1;
175	return 0;
176}
177early_param("numa_debug", parse_debug);
178
179static int __init parse_numa(char *parm)
180{
181	if (strcmp(parm, numa_mode_plain.name) == 0)
182		mode = &numa_mode_plain;
183#ifdef CONFIG_NUMA_EMU
184	if (strcmp(parm, numa_mode_emu.name) == 0)
185		mode = &numa_mode_emu;
186#endif
187	return 0;
188}
189early_param("numa", parse_numa);