xref: /linux-6.15/include/linux/memory_hotplug.h (revision 7170e604)
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 
10 struct page;
11 struct zone;
12 struct pglist_data;
13 struct mem_section;
14 struct memory_block;
15 struct resource;
16 struct vmem_altmap;
17 
18 #ifdef CONFIG_MEMORY_HOTPLUG
19 /*
20  * Return page for the valid pfn only if the page is online. All pfn
21  * walkers which rely on the fully initialized page->flags and others
22  * should use this rather than pfn_valid && pfn_to_page
23  */
24 #define pfn_to_online_page(pfn)				\
25 ({							\
26 	struct page *___page = NULL;			\
27 	unsigned long ___nr = pfn_to_section_nr(pfn);	\
28 							\
29 	if (___nr < NR_MEM_SECTIONS && online_section_nr(___nr))\
30 		___page = pfn_to_page(pfn);		\
31 	___page;					\
32 })
33 
34 /*
35  * Types for free bootmem stored in page->lru.next. These have to be in
36  * some random range in unsigned long space for debugging purposes.
37  */
38 enum {
39 	MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE = 12,
40 	SECTION_INFO = MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE,
41 	MIX_SECTION_INFO,
42 	NODE_INFO,
43 	MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE = NODE_INFO,
44 };
45 
46 /* Types for control the zone type of onlined and offlined memory */
47 enum {
48 	MMOP_OFFLINE = -1,
49 	MMOP_ONLINE_KEEP,
50 	MMOP_ONLINE_KERNEL,
51 	MMOP_ONLINE_MOVABLE,
52 };
53 
54 /*
55  * Zone resizing functions
56  *
57  * Note: any attempt to resize a zone should has pgdat_resize_lock()
58  * zone_span_writelock() both held. This ensure the size of a zone
59  * can't be changed while pgdat_resize_lock() held.
60  */
61 static inline unsigned zone_span_seqbegin(struct zone *zone)
62 {
63 	return read_seqbegin(&zone->span_seqlock);
64 }
65 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
66 {
67 	return read_seqretry(&zone->span_seqlock, iv);
68 }
69 static inline void zone_span_writelock(struct zone *zone)
70 {
71 	write_seqlock(&zone->span_seqlock);
72 }
73 static inline void zone_span_writeunlock(struct zone *zone)
74 {
75 	write_sequnlock(&zone->span_seqlock);
76 }
77 static inline void zone_seqlock_init(struct zone *zone)
78 {
79 	seqlock_init(&zone->span_seqlock);
80 }
81 extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages);
82 extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
83 extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
84 /* VM interface that may be used by firmware interface */
85 extern int online_pages(unsigned long, unsigned long, int);
86 extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
87 	unsigned long *valid_start, unsigned long *valid_end);
88 extern void __offline_isolated_pages(unsigned long, unsigned long);
89 
90 typedef void (*online_page_callback_t)(struct page *page);
91 
92 extern int set_online_page_callback(online_page_callback_t callback);
93 extern int restore_online_page_callback(online_page_callback_t callback);
94 
95 extern void __online_page_set_limits(struct page *page);
96 extern void __online_page_increment_counters(struct page *page);
97 extern void __online_page_free(struct page *page);
98 
99 extern int try_online_node(int nid);
100 
101 extern bool memhp_auto_online;
102 /* If movable_node boot option specified */
103 extern bool movable_node_enabled;
104 static inline bool movable_node_is_enabled(void)
105 {
106 	return movable_node_enabled;
107 }
108 
109 #ifdef CONFIG_MEMORY_HOTREMOVE
110 extern bool is_pageblock_removable_nolock(struct page *page);
111 extern int arch_remove_memory(u64 start, u64 size,
112 		struct vmem_altmap *altmap);
113 extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
114 	unsigned long nr_pages, struct vmem_altmap *altmap);
115 #endif /* CONFIG_MEMORY_HOTREMOVE */
116 
117 /* reasonably generic interface to expand the physical pages */
118 extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
119 		struct vmem_altmap *altmap, bool want_memblock);
120 
121 #ifndef CONFIG_ARCH_HAS_ADD_PAGES
122 static inline int add_pages(int nid, unsigned long start_pfn,
123 		unsigned long nr_pages, struct vmem_altmap *altmap,
124 		bool want_memblock)
125 {
126 	return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
127 }
128 #else /* ARCH_HAS_ADD_PAGES */
129 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
130 		struct vmem_altmap *altmap, bool want_memblock);
131 #endif /* ARCH_HAS_ADD_PAGES */
132 
133 #ifdef CONFIG_NUMA
134 extern int memory_add_physaddr_to_nid(u64 start);
135 #else
136 static inline int memory_add_physaddr_to_nid(u64 start)
137 {
138 	return 0;
139 }
140 #endif
141 
142 #ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
143 /*
144  * For supporting node-hotadd, we have to allocate a new pgdat.
145  *
146  * If an arch has generic style NODE_DATA(),
147  * node_data[nid] = kzalloc() works well. But it depends on the architecture.
148  *
149  * In general, generic_alloc_nodedata() is used.
150  * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
151  *
152  */
153 extern pg_data_t *arch_alloc_nodedata(int nid);
154 extern void arch_free_nodedata(pg_data_t *pgdat);
155 extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
156 
157 #else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
158 
159 #define arch_alloc_nodedata(nid)	generic_alloc_nodedata(nid)
160 #define arch_free_nodedata(pgdat)	generic_free_nodedata(pgdat)
161 
162 #ifdef CONFIG_NUMA
163 /*
164  * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
165  * XXX: kmalloc_node() can't work well to get new node's memory at this time.
166  *	Because, pgdat for the new node is not allocated/initialized yet itself.
167  *	To use new node's memory, more consideration will be necessary.
168  */
169 #define generic_alloc_nodedata(nid)				\
170 ({								\
171 	kzalloc(sizeof(pg_data_t), GFP_KERNEL);			\
172 })
173 /*
174  * This definition is just for error path in node hotadd.
175  * For node hotremove, we have to replace this.
176  */
177 #define generic_free_nodedata(pgdat)	kfree(pgdat)
178 
179 extern pg_data_t *node_data[];
180 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
181 {
182 	node_data[nid] = pgdat;
183 }
184 
185 #else /* !CONFIG_NUMA */
186 
187 /* never called */
188 static inline pg_data_t *generic_alloc_nodedata(int nid)
189 {
190 	BUG();
191 	return NULL;
192 }
193 static inline void generic_free_nodedata(pg_data_t *pgdat)
194 {
195 }
196 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
197 {
198 }
199 #endif /* CONFIG_NUMA */
200 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
201 
202 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
203 extern void __init register_page_bootmem_info_node(struct pglist_data *pgdat);
204 #else
205 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
206 {
207 }
208 #endif
209 extern void put_page_bootmem(struct page *page);
210 extern void get_page_bootmem(unsigned long ingo, struct page *page,
211 			     unsigned long type);
212 
213 void get_online_mems(void);
214 void put_online_mems(void);
215 
216 void mem_hotplug_begin(void);
217 void mem_hotplug_done(void);
218 
219 extern void set_zone_contiguous(struct zone *zone);
220 extern void clear_zone_contiguous(struct zone *zone);
221 
222 #else /* ! CONFIG_MEMORY_HOTPLUG */
223 #define pfn_to_online_page(pfn)			\
224 ({						\
225 	struct page *___page = NULL;		\
226 	if (pfn_valid(pfn))			\
227 		___page = pfn_to_page(pfn);	\
228 	___page;				\
229  })
230 
231 static inline unsigned zone_span_seqbegin(struct zone *zone)
232 {
233 	return 0;
234 }
235 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
236 {
237 	return 0;
238 }
239 static inline void zone_span_writelock(struct zone *zone) {}
240 static inline void zone_span_writeunlock(struct zone *zone) {}
241 static inline void zone_seqlock_init(struct zone *zone) {}
242 
243 static inline int mhp_notimplemented(const char *func)
244 {
245 	printk(KERN_WARNING "%s() called, with CONFIG_MEMORY_HOTPLUG disabled\n", func);
246 	dump_stack();
247 	return -ENOSYS;
248 }
249 
250 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
251 {
252 }
253 
254 static inline int try_online_node(int nid)
255 {
256 	return 0;
257 }
258 
259 static inline void get_online_mems(void) {}
260 static inline void put_online_mems(void) {}
261 
262 static inline void mem_hotplug_begin(void) {}
263 static inline void mem_hotplug_done(void) {}
264 
265 static inline bool movable_node_is_enabled(void)
266 {
267 	return false;
268 }
269 #endif /* ! CONFIG_MEMORY_HOTPLUG */
270 
271 #if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
272 /*
273  * pgdat resizing functions
274  */
275 static inline
276 void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
277 {
278 	spin_lock_irqsave(&pgdat->node_size_lock, *flags);
279 }
280 static inline
281 void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
282 {
283 	spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
284 }
285 static inline
286 void pgdat_resize_init(struct pglist_data *pgdat)
287 {
288 	spin_lock_init(&pgdat->node_size_lock);
289 }
290 #else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
291 /*
292  * Stub functions for when hotplug is off
293  */
294 static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
295 static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
296 static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
297 #endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
298 
299 #ifdef CONFIG_MEMORY_HOTREMOVE
300 
301 extern bool is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
302 extern void try_offline_node(int nid);
303 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
304 extern void remove_memory(int nid, u64 start, u64 size);
305 
306 #else
307 static inline bool is_mem_section_removable(unsigned long pfn,
308 					unsigned long nr_pages)
309 {
310 	return false;
311 }
312 
313 static inline void try_offline_node(int nid) {}
314 
315 static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
316 {
317 	return -EINVAL;
318 }
319 
320 static inline void remove_memory(int nid, u64 start, u64 size) {}
321 #endif /* CONFIG_MEMORY_HOTREMOVE */
322 
323 extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
324 		void *arg, int (*func)(struct memory_block *, void *));
325 extern int add_memory(int nid, u64 start, u64 size);
326 extern int add_memory_resource(int nid, struct resource *resource, bool online);
327 extern int arch_add_memory(int nid, u64 start, u64 size,
328 		struct vmem_altmap *altmap, bool want_memblock);
329 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
330 		unsigned long nr_pages, struct vmem_altmap *altmap);
331 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
332 extern bool is_memblock_offlined(struct memory_block *mem);
333 extern void remove_memory(int nid, u64 start, u64 size);
334 extern int sparse_add_one_section(struct pglist_data *pgdat,
335 		unsigned long start_pfn, struct vmem_altmap *altmap);
336 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
337 		unsigned long map_offset, struct vmem_altmap *altmap);
338 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
339 					  unsigned long pnum);
340 extern bool allow_online_pfn_range(int nid, unsigned long pfn, unsigned long nr_pages,
341 		int online_type);
342 extern struct zone *zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
343 		unsigned long nr_pages);
344 #endif /* __LINUX_MEMORY_HOTPLUG_H */
345