xref: /linux-6.15/include/linux/memory_hotplug.h (revision cd00edc1)
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  * pgdat resizing functions
56  */
57 static inline
58 void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
59 {
60 	spin_lock_irqsave(&pgdat->node_size_lock, *flags);
61 }
62 static inline
63 void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
64 {
65 	spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
66 }
67 static inline
68 void pgdat_resize_init(struct pglist_data *pgdat)
69 {
70 	spin_lock_init(&pgdat->node_size_lock);
71 }
72 /*
73  * Zone resizing functions
74  *
75  * Note: any attempt to resize a zone should has pgdat_resize_lock()
76  * zone_span_writelock() both held. This ensure the size of a zone
77  * can't be changed while pgdat_resize_lock() held.
78  */
79 static inline unsigned zone_span_seqbegin(struct zone *zone)
80 {
81 	return read_seqbegin(&zone->span_seqlock);
82 }
83 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
84 {
85 	return read_seqretry(&zone->span_seqlock, iv);
86 }
87 static inline void zone_span_writelock(struct zone *zone)
88 {
89 	write_seqlock(&zone->span_seqlock);
90 }
91 static inline void zone_span_writeunlock(struct zone *zone)
92 {
93 	write_sequnlock(&zone->span_seqlock);
94 }
95 static inline void zone_seqlock_init(struct zone *zone)
96 {
97 	seqlock_init(&zone->span_seqlock);
98 }
99 extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages);
100 extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
101 extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
102 /* VM interface that may be used by firmware interface */
103 extern int online_pages(unsigned long, unsigned long, int);
104 extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
105 	unsigned long *valid_start, unsigned long *valid_end);
106 extern void __offline_isolated_pages(unsigned long, unsigned long);
107 
108 typedef void (*online_page_callback_t)(struct page *page);
109 
110 extern int set_online_page_callback(online_page_callback_t callback);
111 extern int restore_online_page_callback(online_page_callback_t callback);
112 
113 extern void __online_page_set_limits(struct page *page);
114 extern void __online_page_increment_counters(struct page *page);
115 extern void __online_page_free(struct page *page);
116 
117 extern int try_online_node(int nid);
118 
119 extern bool memhp_auto_online;
120 /* If movable_node boot option specified */
121 extern bool movable_node_enabled;
122 static inline bool movable_node_is_enabled(void)
123 {
124 	return movable_node_enabled;
125 }
126 
127 #ifdef CONFIG_MEMORY_HOTREMOVE
128 extern bool is_pageblock_removable_nolock(struct page *page);
129 extern int arch_remove_memory(u64 start, u64 size,
130 		struct vmem_altmap *altmap);
131 extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
132 	unsigned long nr_pages, struct vmem_altmap *altmap);
133 #endif /* CONFIG_MEMORY_HOTREMOVE */
134 
135 /* reasonably generic interface to expand the physical pages */
136 extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
137 		struct vmem_altmap *altmap, bool want_memblock);
138 
139 #ifndef CONFIG_ARCH_HAS_ADD_PAGES
140 static inline int add_pages(int nid, unsigned long start_pfn,
141 		unsigned long nr_pages, struct vmem_altmap *altmap,
142 		bool want_memblock)
143 {
144 	return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
145 }
146 #else /* ARCH_HAS_ADD_PAGES */
147 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
148 		struct vmem_altmap *altmap, bool want_memblock);
149 #endif /* ARCH_HAS_ADD_PAGES */
150 
151 #ifdef CONFIG_NUMA
152 extern int memory_add_physaddr_to_nid(u64 start);
153 #else
154 static inline int memory_add_physaddr_to_nid(u64 start)
155 {
156 	return 0;
157 }
158 #endif
159 
160 #ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
161 /*
162  * For supporting node-hotadd, we have to allocate a new pgdat.
163  *
164  * If an arch has generic style NODE_DATA(),
165  * node_data[nid] = kzalloc() works well. But it depends on the architecture.
166  *
167  * In general, generic_alloc_nodedata() is used.
168  * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
169  *
170  */
171 extern pg_data_t *arch_alloc_nodedata(int nid);
172 extern void arch_free_nodedata(pg_data_t *pgdat);
173 extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
174 
175 #else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
176 
177 #define arch_alloc_nodedata(nid)	generic_alloc_nodedata(nid)
178 #define arch_free_nodedata(pgdat)	generic_free_nodedata(pgdat)
179 
180 #ifdef CONFIG_NUMA
181 /*
182  * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
183  * XXX: kmalloc_node() can't work well to get new node's memory at this time.
184  *	Because, pgdat for the new node is not allocated/initialized yet itself.
185  *	To use new node's memory, more consideration will be necessary.
186  */
187 #define generic_alloc_nodedata(nid)				\
188 ({								\
189 	kzalloc(sizeof(pg_data_t), GFP_KERNEL);			\
190 })
191 /*
192  * This definition is just for error path in node hotadd.
193  * For node hotremove, we have to replace this.
194  */
195 #define generic_free_nodedata(pgdat)	kfree(pgdat)
196 
197 extern pg_data_t *node_data[];
198 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
199 {
200 	node_data[nid] = pgdat;
201 }
202 
203 #else /* !CONFIG_NUMA */
204 
205 /* never called */
206 static inline pg_data_t *generic_alloc_nodedata(int nid)
207 {
208 	BUG();
209 	return NULL;
210 }
211 static inline void generic_free_nodedata(pg_data_t *pgdat)
212 {
213 }
214 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
215 {
216 }
217 #endif /* CONFIG_NUMA */
218 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
219 
220 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
221 extern void __init register_page_bootmem_info_node(struct pglist_data *pgdat);
222 #else
223 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
224 {
225 }
226 #endif
227 extern void put_page_bootmem(struct page *page);
228 extern void get_page_bootmem(unsigned long ingo, struct page *page,
229 			     unsigned long type);
230 
231 void get_online_mems(void);
232 void put_online_mems(void);
233 
234 void mem_hotplug_begin(void);
235 void mem_hotplug_done(void);
236 
237 extern void set_zone_contiguous(struct zone *zone);
238 extern void clear_zone_contiguous(struct zone *zone);
239 
240 #else /* ! CONFIG_MEMORY_HOTPLUG */
241 #define pfn_to_online_page(pfn)			\
242 ({						\
243 	struct page *___page = NULL;		\
244 	if (pfn_valid(pfn))			\
245 		___page = pfn_to_page(pfn);	\
246 	___page;				\
247  })
248 
249 /*
250  * Stub functions for when hotplug is off
251  */
252 static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
253 static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
254 static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
255 
256 static inline unsigned zone_span_seqbegin(struct zone *zone)
257 {
258 	return 0;
259 }
260 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
261 {
262 	return 0;
263 }
264 static inline void zone_span_writelock(struct zone *zone) {}
265 static inline void zone_span_writeunlock(struct zone *zone) {}
266 static inline void zone_seqlock_init(struct zone *zone) {}
267 
268 static inline int mhp_notimplemented(const char *func)
269 {
270 	printk(KERN_WARNING "%s() called, with CONFIG_MEMORY_HOTPLUG disabled\n", func);
271 	dump_stack();
272 	return -ENOSYS;
273 }
274 
275 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
276 {
277 }
278 
279 static inline int try_online_node(int nid)
280 {
281 	return 0;
282 }
283 
284 static inline void get_online_mems(void) {}
285 static inline void put_online_mems(void) {}
286 
287 static inline void mem_hotplug_begin(void) {}
288 static inline void mem_hotplug_done(void) {}
289 
290 static inline bool movable_node_is_enabled(void)
291 {
292 	return false;
293 }
294 #endif /* ! CONFIG_MEMORY_HOTPLUG */
295 
296 #ifdef CONFIG_MEMORY_HOTREMOVE
297 
298 extern bool is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
299 extern void try_offline_node(int nid);
300 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
301 extern void remove_memory(int nid, u64 start, u64 size);
302 
303 #else
304 static inline bool is_mem_section_removable(unsigned long pfn,
305 					unsigned long nr_pages)
306 {
307 	return false;
308 }
309 
310 static inline void try_offline_node(int nid) {}
311 
312 static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
313 {
314 	return -EINVAL;
315 }
316 
317 static inline void remove_memory(int nid, u64 start, u64 size) {}
318 #endif /* CONFIG_MEMORY_HOTREMOVE */
319 
320 extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
321 		void *arg, int (*func)(struct memory_block *, void *));
322 extern int add_memory(int nid, u64 start, u64 size);
323 extern int add_memory_resource(int nid, struct resource *resource, bool online);
324 extern int arch_add_memory(int nid, u64 start, u64 size,
325 		struct vmem_altmap *altmap, bool want_memblock);
326 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
327 		unsigned long nr_pages, struct vmem_altmap *altmap);
328 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
329 extern bool is_memblock_offlined(struct memory_block *mem);
330 extern void remove_memory(int nid, u64 start, u64 size);
331 extern int sparse_add_one_section(struct pglist_data *pgdat,
332 		unsigned long start_pfn, struct vmem_altmap *altmap);
333 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
334 		unsigned long map_offset, struct vmem_altmap *altmap);
335 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
336 					  unsigned long pnum);
337 extern bool allow_online_pfn_range(int nid, unsigned long pfn, unsigned long nr_pages,
338 		int online_type);
339 extern struct zone *zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
340 		unsigned long nr_pages);
341 #endif /* __LINUX_MEMORY_HOTPLUG_H */
342