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/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
 29static void plain_setup(void)
 30{
 31	node_set(0, node_possible_map);
 32}
 33
 34const struct numa_mode numa_mode_plain = {
 35	.name = "plain",
 36	.setup = plain_setup,
 37};
 38
 39static const struct numa_mode *mode = &numa_mode_plain;
 40
 41int numa_pfn_to_nid(unsigned long pfn)
 42{
 43	return mode->__pfn_to_nid ? mode->__pfn_to_nid(pfn) : 0;
 44}
 45
 46void numa_update_cpu_topology(void)
 47{
 48	if (mode->update_cpu_topology)
 49		mode->update_cpu_topology();
 50}
 51
 52int __node_distance(int a, int b)
 53{
 54	return mode->distance ? mode->distance(a, b) : 0;
 55}
 56EXPORT_SYMBOL(__node_distance);
 57
 58int numa_debug_enabled;
 59
 60/*
 61 * numa_setup_memory() - Assign bootmem to nodes
 62 *
 63 * The memory is first added to memblock without any respect to nodes.
 64 * This is fixed before remaining memblock memory is handed over to the
 65 * buddy allocator.
 66 * An important side effect is that large bootmem allocations might easily
 67 * cross node boundaries, which can be needed for large allocations with
 68 * smaller memory stripes in each node (i.e. when using NUMA emulation).
 69 *
 70 * Memory defines nodes:
 71 * Therefore this routine also sets the nodes online with memory.
 72 */
 73static void __init numa_setup_memory(void)
 74{
 75	unsigned long cur_base, align, end_of_dram;
 76	int nid = 0;
 77
 78	end_of_dram = memblock_end_of_DRAM();
 79	align = mode->align ? mode->align() : ULONG_MAX;
 80
 81	/*
 82	 * Step through all available memory and assign it to the nodes
 83	 * indicated by the mode implementation.
 84	 * All nodes which are seen here will be set online.
 85	 */
 86	cur_base = 0;
 87	do {
 88		nid = numa_pfn_to_nid(PFN_DOWN(cur_base));
 89		node_set_online(nid);
 90		memblock_set_node(cur_base, align, &memblock.memory, nid);
 91		cur_base += align;
 92	} while (cur_base < end_of_dram);
 93
 94	/* Allocate and fill out node_data */
 95	for (nid = 0; nid < MAX_NUMNODES; nid++) {
 96		NODE_DATA(nid) = memblock_alloc(sizeof(pg_data_t), 8);
 97		if (!NODE_DATA(nid))
 98			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
 99			      __func__, sizeof(pg_data_t), 8);
100	}
101
102	for_each_online_node(nid) {
103		unsigned long start_pfn, end_pfn;
104		unsigned long t_start, t_end;
105		int i;
106
107		start_pfn = ULONG_MAX;
108		end_pfn = 0;
109		for_each_mem_pfn_range(i, nid, &t_start, &t_end, NULL) {
110			if (t_start < start_pfn)
111				start_pfn = t_start;
112			if (t_end > end_pfn)
113				end_pfn = t_end;
114		}
115		NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
116		NODE_DATA(nid)->node_id = nid;
117	}
118}
119
120/*
121 * numa_setup() - Earliest initialization
122 *
123 * Assign the mode and call the mode's setup routine.
124 */
125void __init numa_setup(void)
126{
127	pr_info("NUMA mode: %s\n", mode->name);
128	nodes_clear(node_possible_map);
129	/* Initially attach all possible CPUs to node 0. */
130	cpumask_copy(&node_to_cpumask_map[0], cpu_possible_mask);
131	if (mode->setup)
132		mode->setup();
133	numa_setup_memory();
134	memblock_dump_all();
135}
136
137/*
138 * numa_init_late() - Initialization initcall
139 *
140 * Register NUMA nodes.
141 */
142static int __init numa_init_late(void)
143{
144	int nid;
145
146	for_each_online_node(nid)
147		register_one_node(nid);
148	return 0;
149}
150arch_initcall(numa_init_late);
151
152static int __init parse_debug(char *parm)
153{
154	numa_debug_enabled = 1;
155	return 0;
156}
157early_param("numa_debug", parse_debug);
158
159static int __init parse_numa(char *parm)
160{
161	if (!parm)
162		return 1;
163	if (strcmp(parm, numa_mode_plain.name) == 0)
164		mode = &numa_mode_plain;
165#ifdef CONFIG_NUMA_EMU
166	if (strcmp(parm, numa_mode_emu.name) == 0)
167		mode = &numa_mode_emu;
168#endif
169	return 0;
170}
171early_param("numa", parse_numa);