1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * NUMA support, based on the x86 implementation.
4 *
5 * Copyright (C) 2015 Cavium Inc.
6 * Author: Ganapatrao Kulkarni <gkulkarni@cavium.com>
7 */
8
9#define pr_fmt(fmt) "NUMA: " fmt
10
11#include <linux/acpi.h>
12#include <linux/memblock.h>
13#include <linux/module.h>
14#include <linux/of.h>
15
16#include <asm/sections.h>
17
18struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
19EXPORT_SYMBOL(node_data);
20nodemask_t numa_nodes_parsed __initdata;
21static int cpu_to_node_map[NR_CPUS] = { [0 ... NR_CPUS-1] = NUMA_NO_NODE };
22
23static int numa_distance_cnt;
24static u8 *numa_distance;
25bool numa_off;
26
27static __init int numa_parse_early_param(char *opt)
28{
29	if (!opt)
30		return -EINVAL;
31	if (str_has_prefix(opt, "off"))
32		numa_off = true;
33
34	return 0;
35}
36early_param("numa", numa_parse_early_param);
37
38cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
39EXPORT_SYMBOL(node_to_cpumask_map);
40
41#ifdef CONFIG_DEBUG_PER_CPU_MAPS
42
43/*
44 * Returns a pointer to the bitmask of CPUs on Node 'node'.
45 */
46const struct cpumask *cpumask_of_node(int node)
47{
48
49	if (node == NUMA_NO_NODE)
50		return cpu_all_mask;
51
52	if (WARN_ON(node < 0 || node >= nr_node_ids))
53		return cpu_none_mask;
54
55	if (WARN_ON(node_to_cpumask_map[node] == NULL))
56		return cpu_online_mask;
57
58	return node_to_cpumask_map[node];
59}
60EXPORT_SYMBOL(cpumask_of_node);
61
62#endif
63
64static void numa_update_cpu(unsigned int cpu, bool remove)
65{
66	int nid = cpu_to_node(cpu);
67
68	if (nid == NUMA_NO_NODE)
69		return;
70
71	if (remove)
72		cpumask_clear_cpu(cpu, node_to_cpumask_map[nid]);
73	else
74		cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
75}
76
77void numa_add_cpu(unsigned int cpu)
78{
79	numa_update_cpu(cpu, false);
80}
81
82void numa_remove_cpu(unsigned int cpu)
83{
84	numa_update_cpu(cpu, true);
85}
86
87void numa_clear_node(unsigned int cpu)
88{
89	numa_remove_cpu(cpu);
90	set_cpu_numa_node(cpu, NUMA_NO_NODE);
91}
92
93/*
94 * Allocate node_to_cpumask_map based on number of available nodes
95 * Requires node_possible_map to be valid.
96 *
97 * Note: cpumask_of_node() is not valid until after this is done.
98 * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
99 */
100static void __init setup_node_to_cpumask_map(void)
101{
102	int node;
103
104	/* setup nr_node_ids if not done yet */
105	if (nr_node_ids == MAX_NUMNODES)
106		setup_nr_node_ids();
107
108	/* allocate and clear the mapping */
109	for (node = 0; node < nr_node_ids; node++) {
110		alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
111		cpumask_clear(node_to_cpumask_map[node]);
112	}
113
114	/* cpumask_of_node() will now work */
115	pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
116}
117
118/*
119 * Set the cpu to node and mem mapping
120 */
121void numa_store_cpu_info(unsigned int cpu)
122{
123	set_cpu_numa_node(cpu, cpu_to_node_map[cpu]);
124}
125
126void __init early_map_cpu_to_node(unsigned int cpu, int nid)
127{
128	/* fallback to node 0 */
129	if (nid < 0 || nid >= MAX_NUMNODES || numa_off)
130		nid = 0;
131
132	cpu_to_node_map[cpu] = nid;
133
134	/*
135	 * We should set the numa node of cpu0 as soon as possible, because it
136	 * has already been set up online before. cpu_to_node(0) will soon be
137	 * called.
138	 */
139	if (!cpu)
140		set_cpu_numa_node(cpu, nid);
141}
142
143#ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
144unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
145EXPORT_SYMBOL(__per_cpu_offset);
146
147int __init early_cpu_to_node(int cpu)
148{
149	return cpu_to_node_map[cpu];
150}
151
152static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
153{
154	return node_distance(early_cpu_to_node(from), early_cpu_to_node(to));
155}
156
157void __init setup_per_cpu_areas(void)
158{
159	unsigned long delta;
160	unsigned int cpu;
161	int rc = -EINVAL;
162
163	if (pcpu_chosen_fc != PCPU_FC_PAGE) {
164		/*
165		 * Always reserve area for module percpu variables.  That's
166		 * what the legacy allocator did.
167		 */
168		rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
169					    PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
170					    pcpu_cpu_distance,
171					    early_cpu_to_node);
172#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
173		if (rc < 0)
174			pr_warn("PERCPU: %s allocator failed (%d), falling back to page size\n",
175				   pcpu_fc_names[pcpu_chosen_fc], rc);
176#endif
177	}
178
179#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
180	if (rc < 0)
181		rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE, early_cpu_to_node);
182#endif
183	if (rc < 0)
184		panic("Failed to initialize percpu areas (err=%d).", rc);
185
186	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
187	for_each_possible_cpu(cpu)
188		__per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
189}
190#endif
191
192/**
193 * numa_add_memblk() - Set node id to memblk
194 * @nid: NUMA node ID of the new memblk
195 * @start: Start address of the new memblk
196 * @end:  End address of the new memblk
197 *
198 * RETURNS:
199 * 0 on success, -errno on failure.
200 */
201int __init numa_add_memblk(int nid, u64 start, u64 end)
202{
203	int ret;
204
205	ret = memblock_set_node(start, (end - start), &memblock.memory, nid);
206	if (ret < 0) {
207		pr_err("memblock [0x%llx - 0x%llx] failed to add on node %d\n",
208			start, (end - 1), nid);
209		return ret;
210	}
211
212	node_set(nid, numa_nodes_parsed);
213	return ret;
214}
215
216/*
217 * Initialize NODE_DATA for a node on the local memory
218 */
219static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
220{
221	const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
222	u64 nd_pa;
223	void *nd;
224	int tnid;
225
226	if (start_pfn >= end_pfn)
227		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
228
229	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
230	if (!nd_pa)
231		panic("Cannot allocate %zu bytes for node %d data\n",
232		      nd_size, nid);
233
234	nd = __va(nd_pa);
235
236	/* report and initialize */
237	pr_info("NODE_DATA [mem %#010Lx-%#010Lx]\n",
238		nd_pa, nd_pa + nd_size - 1);
239	tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
240	if (tnid != nid)
241		pr_info("NODE_DATA(%d) on node %d\n", nid, tnid);
242
243	node_data[nid] = nd;
244	memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
245	NODE_DATA(nid)->node_id = nid;
246	NODE_DATA(nid)->node_start_pfn = start_pfn;
247	NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
248}
249
250/*
251 * numa_free_distance
252 *
253 * The current table is freed.
254 */
255void __init numa_free_distance(void)
256{
257	size_t size;
258
259	if (!numa_distance)
260		return;
261
262	size = numa_distance_cnt * numa_distance_cnt *
263		sizeof(numa_distance[0]);
264
265	memblock_free(numa_distance, size);
266	numa_distance_cnt = 0;
267	numa_distance = NULL;
268}
269
270/*
271 * Create a new NUMA distance table.
272 */
273static int __init numa_alloc_distance(void)
274{
275	size_t size;
276	int i, j;
277
278	size = nr_node_ids * nr_node_ids * sizeof(numa_distance[0]);
279	numa_distance = memblock_alloc(size, PAGE_SIZE);
280	if (WARN_ON(!numa_distance))
281		return -ENOMEM;
282
283	numa_distance_cnt = nr_node_ids;
284
285	/* fill with the default distances */
286	for (i = 0; i < numa_distance_cnt; i++)
287		for (j = 0; j < numa_distance_cnt; j++)
288			numa_distance[i * numa_distance_cnt + j] = i == j ?
289				LOCAL_DISTANCE : REMOTE_DISTANCE;
290
291	pr_debug("Initialized distance table, cnt=%d\n", numa_distance_cnt);
292
293	return 0;
294}
295
296/**
297 * numa_set_distance() - Set inter node NUMA distance from node to node.
298 * @from: the 'from' node to set distance
299 * @to: the 'to'  node to set distance
300 * @distance: NUMA distance
301 *
302 * Set the distance from node @from to @to to @distance.
303 * If distance table doesn't exist, a warning is printed.
304 *
305 * If @from or @to is higher than the highest known node or lower than zero
306 * or @distance doesn't make sense, the call is ignored.
307 */
308void __init numa_set_distance(int from, int to, int distance)
309{
310	if (!numa_distance) {
311		pr_warn_once("Warning: distance table not allocated yet\n");
312		return;
313	}
314
315	if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
316			from < 0 || to < 0) {
317		pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
318			    from, to, distance);
319		return;
320	}
321
322	if ((u8)distance != distance ||
323	    (from == to && distance != LOCAL_DISTANCE)) {
324		pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
325			     from, to, distance);
326		return;
327	}
328
329	numa_distance[from * numa_distance_cnt + to] = distance;
330}
331
332/*
333 * Return NUMA distance @from to @to
334 */
335int __node_distance(int from, int to)
336{
337	if (from >= numa_distance_cnt || to >= numa_distance_cnt)
338		return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
339	return numa_distance[from * numa_distance_cnt + to];
340}
341EXPORT_SYMBOL(__node_distance);
342
343static int __init numa_register_nodes(void)
344{
345	int nid;
346	struct memblock_region *mblk;
347
348	/* Check that valid nid is set to memblks */
349	for_each_mem_region(mblk) {
350		int mblk_nid = memblock_get_region_node(mblk);
351		phys_addr_t start = mblk->base;
352		phys_addr_t end = mblk->base + mblk->size - 1;
353
354		if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) {
355			pr_warn("Warning: invalid memblk node %d [mem %pap-%pap]\n",
356				mblk_nid, &start, &end);
357			return -EINVAL;
358		}
359	}
360
361	/* Finally register nodes. */
362	for_each_node_mask(nid, numa_nodes_parsed) {
363		unsigned long start_pfn, end_pfn;
364
365		get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
366		setup_node_data(nid, start_pfn, end_pfn);
367		node_set_online(nid);
368	}
369
370	/* Setup online nodes to actual nodes*/
371	node_possible_map = numa_nodes_parsed;
372
373	return 0;
374}
375
376static int __init numa_init(int (*init_func)(void))
377{
378	int ret;
379
380	nodes_clear(numa_nodes_parsed);
381	nodes_clear(node_possible_map);
382	nodes_clear(node_online_map);
383
384	ret = numa_alloc_distance();
385	if (ret < 0)
386		return ret;
387
388	ret = init_func();
389	if (ret < 0)
390		goto out_free_distance;
391
392	if (nodes_empty(numa_nodes_parsed)) {
393		pr_info("No NUMA configuration found\n");
394		ret = -EINVAL;
395		goto out_free_distance;
396	}
397
398	ret = numa_register_nodes();
399	if (ret < 0)
400		goto out_free_distance;
401
402	setup_node_to_cpumask_map();
403
404	return 0;
405out_free_distance:
406	numa_free_distance();
407	return ret;
408}
409
410/**
411 * dummy_numa_init() - Fallback dummy NUMA init
412 *
413 * Used if there's no underlying NUMA architecture, NUMA initialization
414 * fails, or NUMA is disabled on the command line.
415 *
416 * Must online at least one node (node 0) and add memory blocks that cover all
417 * allowed memory. It is unlikely that this function fails.
418 *
419 * Return: 0 on success, -errno on failure.
420 */
421static int __init dummy_numa_init(void)
422{
423	phys_addr_t start = memblock_start_of_DRAM();
424	phys_addr_t end = memblock_end_of_DRAM() - 1;
425	int ret;
426
427	if (numa_off)
428		pr_info("NUMA disabled\n"); /* Forced off on command line. */
429	pr_info("Faking a node at [mem %pap-%pap]\n", &start, &end);
430
431	ret = numa_add_memblk(0, start, end + 1);
432	if (ret) {
433		pr_err("NUMA init failed\n");
434		return ret;
435	}
436
437	numa_off = true;
438	return 0;
439}
440
441#ifdef CONFIG_ACPI_NUMA
442static int __init arch_acpi_numa_init(void)
443{
444	int ret;
445
446	ret = acpi_numa_init();
447	if (ret) {
448		pr_info("Failed to initialise from firmware\n");
449		return ret;
450	}
451
452	return srat_disabled() ? -EINVAL : 0;
453}
454#else
455static int __init arch_acpi_numa_init(void)
456{
457	return -EOPNOTSUPP;
458}
459#endif
460
461/**
462 * arch_numa_init() - Initialize NUMA
463 *
464 * Try each configured NUMA initialization method until one succeeds. The
465 * last fallback is dummy single node config encompassing whole memory.
466 */
467void __init arch_numa_init(void)
468{
469	if (!numa_off) {
470		if (!acpi_disabled && !numa_init(arch_acpi_numa_init))
471			return;
472		if (acpi_disabled && !numa_init(of_numa_init))
473			return;
474	}
475
476	numa_init(dummy_numa_init);
477}
478