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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_MEMORY_HOTPLUG_H
3#define __LINUX_MEMORY_HOTPLUG_H
4
5#include <linux/mmzone.h>
6#include <linux/spinlock.h>
7#include <linux/notifier.h>
8#include <linux/bug.h>
9
10struct page;
11struct zone;
12struct pglist_data;
13struct mem_section;
14struct memory_group;
15struct resource;
16struct vmem_altmap;
17struct dev_pagemap;
18
19#ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
20/*
21 * For supporting node-hotadd, we have to allocate a new pgdat.
22 *
23 * If an arch has generic style NODE_DATA(),
24 * node_data[nid] = kzalloc() works well. But it depends on the architecture.
25 *
26 * In general, generic_alloc_nodedata() is used.
27 *
28 */
29extern pg_data_t *arch_alloc_nodedata(int nid);
30extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
31
32#else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
33
34#define arch_alloc_nodedata(nid) generic_alloc_nodedata(nid)
35
36#ifdef CONFIG_NUMA
37/*
38 * XXX: node aware allocation can't work well to get new node's memory at this time.
39 * Because, pgdat for the new node is not allocated/initialized yet itself.
40 * To use new node's memory, more consideration will be necessary.
41 */
42#define generic_alloc_nodedata(nid) \
43({ \
44 memblock_alloc(sizeof(*pgdat), SMP_CACHE_BYTES); \
45})
46
47extern pg_data_t *node_data[];
48static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
49{
50 node_data[nid] = pgdat;
51}
52
53#else /* !CONFIG_NUMA */
54
55/* never called */
56static inline pg_data_t *generic_alloc_nodedata(int nid)
57{
58 BUG();
59 return NULL;
60}
61static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
62{
63}
64#endif /* CONFIG_NUMA */
65#endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
66
67#ifdef CONFIG_MEMORY_HOTPLUG
68struct page *pfn_to_online_page(unsigned long pfn);
69
70/* Types for control the zone type of onlined and offlined memory */
71enum {
72 /* Offline the memory. */
73 MMOP_OFFLINE = 0,
74 /* Online the memory. Zone depends, see default_zone_for_pfn(). */
75 MMOP_ONLINE,
76 /* Online the memory to ZONE_NORMAL. */
77 MMOP_ONLINE_KERNEL,
78 /* Online the memory to ZONE_MOVABLE. */
79 MMOP_ONLINE_MOVABLE,
80};
81
82/* Flags for add_memory() and friends to specify memory hotplug details. */
83typedef int __bitwise mhp_t;
84
85/* No special request */
86#define MHP_NONE ((__force mhp_t)0)
87/*
88 * Allow merging of the added System RAM resource with adjacent,
89 * mergeable resources. After a successful call to add_memory_resource()
90 * with this flag set, the resource pointer must no longer be used as it
91 * might be stale, or the resource might have changed.
92 */
93#define MHP_MERGE_RESOURCE ((__force mhp_t)BIT(0))
94
95/*
96 * We want memmap (struct page array) to be self contained.
97 * To do so, we will use the beginning of the hot-added range to build
98 * the page tables for the memmap array that describes the entire range.
99 * Only selected architectures support it with SPARSE_VMEMMAP.
100 * This is only a hint, the core kernel can decide to not do this based on
101 * different alignment checks.
102 */
103#define MHP_MEMMAP_ON_MEMORY ((__force mhp_t)BIT(1))
104/*
105 * The nid field specifies a memory group id (mgid) instead. The memory group
106 * implies the node id (nid).
107 */
108#define MHP_NID_IS_MGID ((__force mhp_t)BIT(2))
109
110/*
111 * Extended parameters for memory hotplug:
112 * altmap: alternative allocator for memmap array (optional)
113 * pgprot: page protection flags to apply to newly created page tables
114 * (required)
115 */
116struct mhp_params {
117 struct vmem_altmap *altmap;
118 pgprot_t pgprot;
119 struct dev_pagemap *pgmap;
120};
121
122bool mhp_range_allowed(u64 start, u64 size, bool need_mapping);
123struct range mhp_get_pluggable_range(bool need_mapping);
124
125/*
126 * Zone resizing functions
127 *
128 * Note: any attempt to resize a zone should has pgdat_resize_lock()
129 * zone_span_writelock() both held. This ensure the size of a zone
130 * can't be changed while pgdat_resize_lock() held.
131 */
132static inline unsigned zone_span_seqbegin(struct zone *zone)
133{
134 return read_seqbegin(&zone->span_seqlock);
135}
136static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
137{
138 return read_seqretry(&zone->span_seqlock, iv);
139}
140static inline void zone_span_writelock(struct zone *zone)
141{
142 write_seqlock(&zone->span_seqlock);
143}
144static inline void zone_span_writeunlock(struct zone *zone)
145{
146 write_sequnlock(&zone->span_seqlock);
147}
148static inline void zone_seqlock_init(struct zone *zone)
149{
150 seqlock_init(&zone->span_seqlock);
151}
152extern void adjust_present_page_count(struct page *page,
153 struct memory_group *group,
154 long nr_pages);
155/* VM interface that may be used by firmware interface */
156extern int mhp_init_memmap_on_memory(unsigned long pfn, unsigned long nr_pages,
157 struct zone *zone);
158extern void mhp_deinit_memmap_on_memory(unsigned long pfn, unsigned long nr_pages);
159extern int online_pages(unsigned long pfn, unsigned long nr_pages,
160 struct zone *zone, struct memory_group *group);
161extern void __offline_isolated_pages(unsigned long start_pfn,
162 unsigned long end_pfn);
163
164typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
165
166extern void generic_online_page(struct page *page, unsigned int order);
167extern int set_online_page_callback(online_page_callback_t callback);
168extern int restore_online_page_callback(online_page_callback_t callback);
169
170extern int try_online_node(int nid);
171
172extern int arch_add_memory(int nid, u64 start, u64 size,
173 struct mhp_params *params);
174extern u64 max_mem_size;
175
176extern int mhp_online_type_from_str(const char *str);
177
178/* Default online_type (MMOP_*) when new memory blocks are added. */
179extern int mhp_default_online_type;
180/* If movable_node boot option specified */
181extern bool movable_node_enabled;
182static inline bool movable_node_is_enabled(void)
183{
184 return movable_node_enabled;
185}
186
187extern void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap);
188extern void __remove_pages(unsigned long start_pfn, unsigned long nr_pages,
189 struct vmem_altmap *altmap);
190
191/* reasonably generic interface to expand the physical pages */
192extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
193 struct mhp_params *params);
194
195#ifndef CONFIG_ARCH_HAS_ADD_PAGES
196static inline int add_pages(int nid, unsigned long start_pfn,
197 unsigned long nr_pages, struct mhp_params *params)
198{
199 return __add_pages(nid, start_pfn, nr_pages, params);
200}
201#else /* ARCH_HAS_ADD_PAGES */
202int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
203 struct mhp_params *params);
204#endif /* ARCH_HAS_ADD_PAGES */
205
206void get_online_mems(void);
207void put_online_mems(void);
208
209void mem_hotplug_begin(void);
210void mem_hotplug_done(void);
211
212/* See kswapd_is_running() */
213static inline void pgdat_kswapd_lock(pg_data_t *pgdat)
214{
215 mutex_lock(&pgdat->kswapd_lock);
216}
217
218static inline void pgdat_kswapd_unlock(pg_data_t *pgdat)
219{
220 mutex_unlock(&pgdat->kswapd_lock);
221}
222
223static inline void pgdat_kswapd_lock_init(pg_data_t *pgdat)
224{
225 mutex_init(&pgdat->kswapd_lock);
226}
227
228#else /* ! CONFIG_MEMORY_HOTPLUG */
229#define pfn_to_online_page(pfn) \
230({ \
231 struct page *___page = NULL; \
232 if (pfn_valid(pfn)) \
233 ___page = pfn_to_page(pfn); \
234 ___page; \
235 })
236
237static inline unsigned zone_span_seqbegin(struct zone *zone)
238{
239 return 0;
240}
241static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
242{
243 return 0;
244}
245static inline void zone_span_writelock(struct zone *zone) {}
246static inline void zone_span_writeunlock(struct zone *zone) {}
247static inline void zone_seqlock_init(struct zone *zone) {}
248
249static inline int try_online_node(int nid)
250{
251 return 0;
252}
253
254static inline void get_online_mems(void) {}
255static inline void put_online_mems(void) {}
256
257static inline void mem_hotplug_begin(void) {}
258static inline void mem_hotplug_done(void) {}
259
260static inline bool movable_node_is_enabled(void)
261{
262 return false;
263}
264
265static inline void pgdat_kswapd_lock(pg_data_t *pgdat) {}
266static inline void pgdat_kswapd_unlock(pg_data_t *pgdat) {}
267static inline void pgdat_kswapd_lock_init(pg_data_t *pgdat) {}
268#endif /* ! CONFIG_MEMORY_HOTPLUG */
269
270/*
271 * Keep this declaration outside CONFIG_MEMORY_HOTPLUG as some
272 * platforms might override and use arch_get_mappable_range()
273 * for internal non memory hotplug purposes.
274 */
275struct range arch_get_mappable_range(void);
276
277#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
278/*
279 * pgdat resizing functions
280 */
281static inline
282void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
283{
284 spin_lock_irqsave(&pgdat->node_size_lock, *flags);
285}
286static inline
287void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
288{
289 spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
290}
291static inline
292void pgdat_resize_init(struct pglist_data *pgdat)
293{
294 spin_lock_init(&pgdat->node_size_lock);
295}
296#else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
297/*
298 * Stub functions for when hotplug is off
299 */
300static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
301static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
302static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
303#endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
304
305#ifdef CONFIG_MEMORY_HOTREMOVE
306
307extern void try_offline_node(int nid);
308extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages,
309 struct zone *zone, struct memory_group *group);
310extern int remove_memory(u64 start, u64 size);
311extern void __remove_memory(u64 start, u64 size);
312extern int offline_and_remove_memory(u64 start, u64 size);
313
314#else
315static inline void try_offline_node(int nid) {}
316
317static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages,
318 struct zone *zone, struct memory_group *group)
319{
320 return -EINVAL;
321}
322
323static inline int remove_memory(u64 start, u64 size)
324{
325 return -EBUSY;
326}
327
328static inline void __remove_memory(u64 start, u64 size) {}
329#endif /* CONFIG_MEMORY_HOTREMOVE */
330
331#ifdef CONFIG_MEMORY_HOTPLUG
332extern void __ref free_area_init_core_hotplug(struct pglist_data *pgdat);
333extern int __add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
334extern int add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
335extern int add_memory_resource(int nid, struct resource *resource,
336 mhp_t mhp_flags);
337extern int add_memory_driver_managed(int nid, u64 start, u64 size,
338 const char *resource_name,
339 mhp_t mhp_flags);
340extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
341 unsigned long nr_pages,
342 struct vmem_altmap *altmap, int migratetype);
343extern void remove_pfn_range_from_zone(struct zone *zone,
344 unsigned long start_pfn,
345 unsigned long nr_pages);
346extern int sparse_add_section(int nid, unsigned long pfn,
347 unsigned long nr_pages, struct vmem_altmap *altmap,
348 struct dev_pagemap *pgmap);
349extern void sparse_remove_section(unsigned long pfn, unsigned long nr_pages,
350 struct vmem_altmap *altmap);
351extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
352 unsigned long pnum);
353extern struct zone *zone_for_pfn_range(int online_type, int nid,
354 struct memory_group *group, unsigned long start_pfn,
355 unsigned long nr_pages);
356extern int arch_create_linear_mapping(int nid, u64 start, u64 size,
357 struct mhp_params *params);
358void arch_remove_linear_mapping(u64 start, u64 size);
359#endif /* CONFIG_MEMORY_HOTPLUG */
360
361#endif /* __LINUX_MEMORY_HOTPLUG_H */