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), 8);
 61	memset(res, 0, sizeof(pg_data_t));
 62	return res;
 63}
 64
 65/*
 66 * numa_setup_memory() - Assign bootmem to nodes
 67 *
 68 * The memory is first added to memblock without any respect to nodes.
 69 * This is fixed before remaining memblock memory is handed over to the
 70 * buddy allocator.
 71 * An important side effect is that large bootmem allocations might easily
 72 * cross node boundaries, which can be needed for large allocations with
 73 * smaller memory stripes in each node (i.e. when using NUMA emulation).
 74 *
 75 * Memory defines nodes:
 76 * Therefore this routine also sets the nodes online with memory.
 77 */
 78static void __init numa_setup_memory(void)
 79{
 80	unsigned long cur_base, align, end_of_dram;
 81	int nid = 0;
 82
 83	end_of_dram = memblock_end_of_DRAM();
 84	align = mode->align ? mode->align() : ULONG_MAX;
 85
 86	/*
 87	 * Step through all available memory and assign it to the nodes
 88	 * indicated by the mode implementation.
 89	 * All nodes which are seen here will be set online.
 90	 */
 91	cur_base = 0;
 92	do {
 93		nid = numa_pfn_to_nid(PFN_DOWN(cur_base));
 94		node_set_online(nid);
 95		memblock_set_node(cur_base, align, &memblock.memory, nid);
 96		cur_base += align;
 97	} while (cur_base < end_of_dram);
 98
 99	/* Allocate and fill out node_data */
100	for (nid = 0; nid < MAX_NUMNODES; nid++)
101		NODE_DATA(nid) = alloc_node_data();
102
103	for_each_online_node(nid) {
104		unsigned long start_pfn, end_pfn;
105		unsigned long t_start, t_end;
106		int i;
107
108		start_pfn = ULONG_MAX;
109		end_pfn = 0;
110		for_each_mem_pfn_range(i, nid, &t_start, &t_end, NULL) {
111			if (t_start < start_pfn)
112				start_pfn = t_start;
113			if (t_end > end_pfn)
114				end_pfn = t_end;
115		}
116		NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
117		NODE_DATA(nid)->node_id = nid;
118	}
119}
120
121/*
122 * numa_setup() - Earliest initialization
123 *
124 * Assign the mode and call the mode's setup routine.
125 */
126void __init numa_setup(void)
127{
128	pr_info("NUMA mode: %s\n", mode->name);
129	if (mode->setup)
130		mode->setup();
131	numa_setup_memory();
132	memblock_dump_all();
133}
134
135
136/*
137 * numa_init_early() - Initialization initcall
138 *
139 * This runs when only one CPU is online and before the first
140 * topology update is called for by the scheduler.
141 */
142static int __init numa_init_early(void)
143{
144	/* Attach all possible CPUs to node 0 for now. */
145	cpumask_copy(&node_to_cpumask_map[0], cpu_possible_mask);
146	return 0;
147}
148early_initcall(numa_init_early);
149
150/*
151 * numa_init_late() - Initialization initcall
152 *
153 * Register NUMA nodes.
154 */
155static int __init numa_init_late(void)
156{
157	int nid;
158
159	for_each_online_node(nid)
160		register_one_node(nid);
161	return 0;
162}
163arch_initcall(numa_init_late);
164
165static int __init parse_debug(char *parm)
166{
167	numa_debug_enabled = 1;
168	return 0;
169}
170early_param("numa_debug", parse_debug);
171
172static int __init parse_numa(char *parm)
173{
174	if (strcmp(parm, numa_mode_plain.name) == 0)
175		mode = &numa_mode_plain;
176#ifdef CONFIG_NUMA_EMU
177	if (strcmp(parm, numa_mode_emu.name) == 0)
178		mode = &numa_mode_emu;
179#endif
180	return 0;
181}
182early_param("numa", parse_numa);