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/acpi.h>
 17#include <asm/sections.h>
 18
 19struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
 20EXPORT_SYMBOL(node_data);
 21nodemask_t numa_nodes_parsed __initdata;
 22static int cpu_to_node_map[NR_CPUS] = { [0 ... NR_CPUS-1] = NUMA_NO_NODE };
 23
 24static int numa_distance_cnt;
 25static u8 *numa_distance;
 26bool numa_off;
 27
 28static __init int numa_parse_early_param(char *opt)
 29{
 30	if (!opt)
 31		return -EINVAL;
 32	if (str_has_prefix(opt, "off"))
 33		numa_off = true;
 34
 35	return 0;
 36}
 37early_param("numa", numa_parse_early_param);
 38
 39cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
 40EXPORT_SYMBOL(node_to_cpumask_map);
 41
 42#ifdef CONFIG_DEBUG_PER_CPU_MAPS
 43
 44/*
 45 * Returns a pointer to the bitmask of CPUs on Node 'node'.
 46 */
 47const struct cpumask *cpumask_of_node(int node)
 48{
 49	if (WARN_ON(node >= nr_node_ids))
 50		return cpu_none_mask;
 51
 52	if (WARN_ON(node_to_cpumask_map[node] == NULL))
 53		return cpu_online_mask;
 54
 55	return node_to_cpumask_map[node];
 56}
 57EXPORT_SYMBOL(cpumask_of_node);
 58
 59#endif
 60
 61static void numa_update_cpu(unsigned int cpu, bool remove)
 62{
 63	int nid = cpu_to_node(cpu);
 64
 65	if (nid == NUMA_NO_NODE)
 66		return;
 67
 68	if (remove)
 69		cpumask_clear_cpu(cpu, node_to_cpumask_map[nid]);
 70	else
 71		cpumask_set_cpu(cpu, node_to_cpumask_map[nid]);
 72}
 73
 74void numa_add_cpu(unsigned int cpu)
 75{
 76	numa_update_cpu(cpu, false);
 77}
 78
 79void numa_remove_cpu(unsigned int cpu)
 80{
 81	numa_update_cpu(cpu, true);
 82}
 83
 84void numa_clear_node(unsigned int cpu)
 85{
 86	numa_remove_cpu(cpu);
 87	set_cpu_numa_node(cpu, NUMA_NO_NODE);
 88}
 89
 90/*
 91 * Allocate node_to_cpumask_map based on number of available nodes
 92 * Requires node_possible_map to be valid.
 93 *
 94 * Note: cpumask_of_node() is not valid until after this is done.
 95 * (Use CONFIG_DEBUG_PER_CPU_MAPS to check this.)
 96 */
 97static void __init setup_node_to_cpumask_map(void)
 98{
 99	int node;
100
101	/* setup nr_node_ids if not done yet */
102	if (nr_node_ids == MAX_NUMNODES)
103		setup_nr_node_ids();
104
105	/* allocate and clear the mapping */
106	for (node = 0; node < nr_node_ids; node++) {
107		alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
108		cpumask_clear(node_to_cpumask_map[node]);
109	}
110
111	/* cpumask_of_node() will now work */
112	pr_debug("Node to cpumask map for %u nodes\n", nr_node_ids);
113}
114
115/*
116 * Set the cpu to node and mem mapping
117 */
118void numa_store_cpu_info(unsigned int cpu)
119{
120	set_cpu_numa_node(cpu, cpu_to_node_map[cpu]);
121}
122
123void __init early_map_cpu_to_node(unsigned int cpu, int nid)
124{
125	/* fallback to node 0 */
126	if (nid < 0 || nid >= MAX_NUMNODES || numa_off)
127		nid = 0;
128
129	cpu_to_node_map[cpu] = nid;
130
131	/*
132	 * We should set the numa node of cpu0 as soon as possible, because it
133	 * has already been set up online before. cpu_to_node(0) will soon be
134	 * called.
135	 */
136	if (!cpu)
137		set_cpu_numa_node(cpu, nid);
138}
139
140#ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA
141unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
142EXPORT_SYMBOL(__per_cpu_offset);
143
144static int __init early_cpu_to_node(int cpu)
145{
146	return cpu_to_node_map[cpu];
147}
148
149static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
150{
151	return node_distance(early_cpu_to_node(from), early_cpu_to_node(to));
152}
153
154static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size,
155				       size_t align)
156{
157	int nid = early_cpu_to_node(cpu);
158
159	return  memblock_alloc_try_nid(size, align,
160			__pa(MAX_DMA_ADDRESS), MEMBLOCK_ALLOC_ACCESSIBLE, nid);
161}
162
163static void __init pcpu_fc_free(void *ptr, size_t size)
164{
165	memblock_free_early(__pa(ptr), size);
166}
167
168void __init setup_per_cpu_areas(void)
169{
170	unsigned long delta;
171	unsigned int cpu;
172	int rc;
173
174	/*
175	 * Always reserve area for module percpu variables.  That's
176	 * what the legacy allocator did.
177	 */
178	rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
179				    PERCPU_DYNAMIC_RESERVE, PAGE_SIZE,
180				    pcpu_cpu_distance,
181				    pcpu_fc_alloc, pcpu_fc_free);
182	if (rc < 0)
183		panic("Failed to initialize percpu areas.");
184
185	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
186	for_each_possible_cpu(cpu)
187		__per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
188}
189#endif
190
191/**
192 * numa_add_memblk() - Set node id to memblk
193 * @nid: NUMA node ID of the new memblk
194 * @start: Start address of the new memblk
195 * @end:  End address of the new memblk
196 *
197 * RETURNS:
198 * 0 on success, -errno on failure.
199 */
200int __init numa_add_memblk(int nid, u64 start, u64 end)
201{
202	int ret;
203
204	ret = memblock_set_node(start, (end - start), &memblock.memory, nid);
205	if (ret < 0) {
206		pr_err("memblock [0x%llx - 0x%llx] failed to add on node %d\n",
207			start, (end - 1), nid);
208		return ret;
209	}
210
211	node_set(nid, numa_nodes_parsed);
212	return ret;
213}
214
215/*
216 * Initialize NODE_DATA for a node on the local memory
217 */
218static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
219{
220	const size_t nd_size = roundup(sizeof(pg_data_t), SMP_CACHE_BYTES);
221	u64 nd_pa;
222	void *nd;
223	int tnid;
224
225	if (start_pfn >= end_pfn)
226		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
227
228	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
229	if (!nd_pa)
230		panic("Cannot allocate %zu bytes for node %d data\n",
231		      nd_size, nid);
232
233	nd = __va(nd_pa);
234
235	/* report and initialize */
236	pr_info("NODE_DATA [mem %#010Lx-%#010Lx]\n",
237		nd_pa, nd_pa + nd_size - 1);
238	tnid = early_pfn_to_nid(nd_pa >> PAGE_SHIFT);
239	if (tnid != nid)
240		pr_info("NODE_DATA(%d) on node %d\n", nid, tnid);
241
242	node_data[nid] = nd;
243	memset(NODE_DATA(nid), 0, sizeof(pg_data_t));
244	NODE_DATA(nid)->node_id = nid;
245	NODE_DATA(nid)->node_start_pfn = start_pfn;
246	NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
247}
248
249/*
250 * numa_free_distance
251 *
252 * The current table is freed.
253 */
254void __init numa_free_distance(void)
255{
256	size_t size;
257
258	if (!numa_distance)
259		return;
260
261	size = numa_distance_cnt * numa_distance_cnt *
262		sizeof(numa_distance[0]);
263
264	memblock_free(__pa(numa_distance), size);
265	numa_distance_cnt = 0;
266	numa_distance = NULL;
267}
268
269/*
270 * Create a new NUMA distance table.
271 */
272static int __init numa_alloc_distance(void)
273{
274	size_t size;
275	u64 phys;
276	int i, j;
277
278	size = nr_node_ids * nr_node_ids * sizeof(numa_distance[0]);
279	phys = memblock_find_in_range(0, PFN_PHYS(max_pfn),
280				      size, PAGE_SIZE);
281	if (WARN_ON(!phys))
282		return -ENOMEM;
283
284	memblock_reserve(phys, size);
285
286	numa_distance = __va(phys);
287	numa_distance_cnt = nr_node_ids;
288
289	/* fill with the default distances */
290	for (i = 0; i < numa_distance_cnt; i++)
291		for (j = 0; j < numa_distance_cnt; j++)
292			numa_distance[i * numa_distance_cnt + j] = i == j ?
293				LOCAL_DISTANCE : REMOTE_DISTANCE;
294
295	pr_debug("Initialized distance table, cnt=%d\n", numa_distance_cnt);
296
297	return 0;
298}
299
300/**
301 * numa_set_distance() - Set inter node NUMA distance from node to node.
302 * @from: the 'from' node to set distance
303 * @to: the 'to'  node to set distance
304 * @distance: NUMA distance
305 *
306 * Set the distance from node @from to @to to @distance.
307 * If distance table doesn't exist, a warning is printed.
308 *
309 * If @from or @to is higher than the highest known node or lower than zero
310 * or @distance doesn't make sense, the call is ignored.
311 */
312void __init numa_set_distance(int from, int to, int distance)
313{
314	if (!numa_distance) {
315		pr_warn_once("Warning: distance table not allocated yet\n");
316		return;
317	}
318
319	if (from >= numa_distance_cnt || to >= numa_distance_cnt ||
320			from < 0 || to < 0) {
321		pr_warn_once("Warning: node ids are out of bound, from=%d to=%d distance=%d\n",
322			    from, to, distance);
323		return;
324	}
325
326	if ((u8)distance != distance ||
327	    (from == to && distance != LOCAL_DISTANCE)) {
328		pr_warn_once("Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
329			     from, to, distance);
330		return;
331	}
332
333	numa_distance[from * numa_distance_cnt + to] = distance;
334}
335
336/*
337 * Return NUMA distance @from to @to
338 */
339int __node_distance(int from, int to)
340{
341	if (from >= numa_distance_cnt || to >= numa_distance_cnt)
342		return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
343	return numa_distance[from * numa_distance_cnt + to];
344}
345EXPORT_SYMBOL(__node_distance);
346
347static int __init numa_register_nodes(void)
348{
349	int nid;
350	struct memblock_region *mblk;
351
352	/* Check that valid nid is set to memblks */
353	for_each_memblock(memory, mblk) {
354		int mblk_nid = memblock_get_region_node(mblk);
355
356		if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) {
357			pr_warn("Warning: invalid memblk node %d [mem %#010Lx-%#010Lx]\n",
358				mblk_nid, mblk->base,
359				mblk->base + mblk->size - 1);
360			return -EINVAL;
361		}
362	}
363
364	/* Finally register nodes. */
365	for_each_node_mask(nid, numa_nodes_parsed) {
366		unsigned long start_pfn, end_pfn;
367
368		get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
369		setup_node_data(nid, start_pfn, end_pfn);
370		node_set_online(nid);
371	}
372
373	/* Setup online nodes to actual nodes*/
374	node_possible_map = numa_nodes_parsed;
375
376	return 0;
377}
378
379static int __init numa_init(int (*init_func)(void))
380{
381	int ret;
382
383	nodes_clear(numa_nodes_parsed);
384	nodes_clear(node_possible_map);
385	nodes_clear(node_online_map);
386
387	ret = numa_alloc_distance();
388	if (ret < 0)
389		return ret;
390
391	ret = init_func();
392	if (ret < 0)
393		goto out_free_distance;
394
395	if (nodes_empty(numa_nodes_parsed)) {
396		pr_info("No NUMA configuration found\n");
397		ret = -EINVAL;
398		goto out_free_distance;
399	}
400
401	ret = numa_register_nodes();
402	if (ret < 0)
403		goto out_free_distance;
404
405	setup_node_to_cpumask_map();
406
407	return 0;
408out_free_distance:
409	numa_free_distance();
410	return ret;
411}
412
413/**
414 * dummy_numa_init() - Fallback dummy NUMA init
415 *
416 * Used if there's no underlying NUMA architecture, NUMA initialization
417 * fails, or NUMA is disabled on the command line.
418 *
419 * Must online at least one node (node 0) and add memory blocks that cover all
420 * allowed memory. It is unlikely that this function fails.
421 *
422 * Return: 0 on success, -errno on failure.
423 */
424static int __init dummy_numa_init(void)
425{
426	int ret;
427	struct memblock_region *mblk;
428
429	if (numa_off)
430		pr_info("NUMA disabled\n"); /* Forced off on command line. */
431	pr_info("Faking a node at [mem %#018Lx-%#018Lx]\n",
432		memblock_start_of_DRAM(), memblock_end_of_DRAM() - 1);
433
434	for_each_memblock(memory, mblk) {
435		ret = numa_add_memblk(0, mblk->base, mblk->base + mblk->size);
436		if (!ret)
437			continue;
438
439		pr_err("NUMA init failed\n");
440		return ret;
441	}
442
443	numa_off = true;
444	return 0;
445}
446
447/**
448 * arm64_numa_init() - Initialize NUMA
449 *
450 * Try each configured NUMA initialization method until one succeeds. The
451 * last fallback is dummy single node config encomapssing whole memory.
452 */
453void __init arm64_numa_init(void)
454{
455	if (!numa_off) {
456		if (!acpi_disabled && !numa_init(arm64_acpi_numa_init))
457			return;
458		if (acpi_disabled && !numa_init(of_numa_init))
459			return;
460	}
461
462	numa_init(dummy_numa_init);
463}