xref: /linux-6.15/include/linux/memory_hotplug.h (revision 8ea8814f)
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 ___pfn = pfn;				   \
28 	unsigned long ___nr = pfn_to_section_nr(___pfn);	   \
29 								   \
30 	if (___nr < NR_MEM_SECTIONS && online_section_nr(___nr) && \
31 	    pfn_valid_within(___pfn))				   \
32 		___page = pfn_to_page(___pfn);			   \
33 	___page;						   \
34 })
35 
36 /*
37  * Types for free bootmem stored in page->lru.next. These have to be in
38  * some random range in unsigned long space for debugging purposes.
39  */
40 enum {
41 	MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE = 12,
42 	SECTION_INFO = MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE,
43 	MIX_SECTION_INFO,
44 	NODE_INFO,
45 	MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE = NODE_INFO,
46 };
47 
48 /* Types for control the zone type of onlined and offlined memory */
49 enum {
50 	MMOP_OFFLINE = -1,
51 	MMOP_ONLINE_KEEP,
52 	MMOP_ONLINE_KERNEL,
53 	MMOP_ONLINE_MOVABLE,
54 };
55 
56 /*
57  * Zone resizing functions
58  *
59  * Note: any attempt to resize a zone should has pgdat_resize_lock()
60  * zone_span_writelock() both held. This ensure the size of a zone
61  * can't be changed while pgdat_resize_lock() held.
62  */
63 static inline unsigned zone_span_seqbegin(struct zone *zone)
64 {
65 	return read_seqbegin(&zone->span_seqlock);
66 }
67 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
68 {
69 	return read_seqretry(&zone->span_seqlock, iv);
70 }
71 static inline void zone_span_writelock(struct zone *zone)
72 {
73 	write_seqlock(&zone->span_seqlock);
74 }
75 static inline void zone_span_writeunlock(struct zone *zone)
76 {
77 	write_sequnlock(&zone->span_seqlock);
78 }
79 static inline void zone_seqlock_init(struct zone *zone)
80 {
81 	seqlock_init(&zone->span_seqlock);
82 }
83 extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages);
84 extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
85 extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
86 /* VM interface that may be used by firmware interface */
87 extern int online_pages(unsigned long, unsigned long, int);
88 extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
89 	unsigned long *valid_start, unsigned long *valid_end);
90 extern void __offline_isolated_pages(unsigned long, unsigned long);
91 
92 typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
93 
94 extern int set_online_page_callback(online_page_callback_t callback);
95 extern int restore_online_page_callback(online_page_callback_t callback);
96 
97 extern void __online_page_set_limits(struct page *page);
98 extern void __online_page_increment_counters(struct page *page);
99 extern void __online_page_free(struct page *page);
100 
101 extern int try_online_node(int nid);
102 
103 extern u64 max_mem_size;
104 
105 extern bool memhp_auto_online;
106 /* If movable_node boot option specified */
107 extern bool movable_node_enabled;
108 static inline bool movable_node_is_enabled(void)
109 {
110 	return movable_node_enabled;
111 }
112 
113 #ifdef CONFIG_MEMORY_HOTREMOVE
114 extern int arch_remove_memory(int nid, u64 start, u64 size,
115 				struct vmem_altmap *altmap);
116 extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
117 	unsigned long nr_pages, struct vmem_altmap *altmap);
118 #endif /* CONFIG_MEMORY_HOTREMOVE */
119 
120 /* reasonably generic interface to expand the physical pages */
121 extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
122 		struct vmem_altmap *altmap, bool want_memblock);
123 
124 #ifndef CONFIG_ARCH_HAS_ADD_PAGES
125 static inline int add_pages(int nid, unsigned long start_pfn,
126 		unsigned long nr_pages, struct vmem_altmap *altmap,
127 		bool want_memblock)
128 {
129 	return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
130 }
131 #else /* ARCH_HAS_ADD_PAGES */
132 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
133 		struct vmem_altmap *altmap, bool want_memblock);
134 #endif /* ARCH_HAS_ADD_PAGES */
135 
136 #ifdef CONFIG_NUMA
137 extern int memory_add_physaddr_to_nid(u64 start);
138 #else
139 static inline int memory_add_physaddr_to_nid(u64 start)
140 {
141 	return 0;
142 }
143 #endif
144 
145 #ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
146 /*
147  * For supporting node-hotadd, we have to allocate a new pgdat.
148  *
149  * If an arch has generic style NODE_DATA(),
150  * node_data[nid] = kzalloc() works well. But it depends on the architecture.
151  *
152  * In general, generic_alloc_nodedata() is used.
153  * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
154  *
155  */
156 extern pg_data_t *arch_alloc_nodedata(int nid);
157 extern void arch_free_nodedata(pg_data_t *pgdat);
158 extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
159 
160 #else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
161 
162 #define arch_alloc_nodedata(nid)	generic_alloc_nodedata(nid)
163 #define arch_free_nodedata(pgdat)	generic_free_nodedata(pgdat)
164 
165 #ifdef CONFIG_NUMA
166 /*
167  * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
168  * XXX: kmalloc_node() can't work well to get new node's memory at this time.
169  *	Because, pgdat for the new node is not allocated/initialized yet itself.
170  *	To use new node's memory, more consideration will be necessary.
171  */
172 #define generic_alloc_nodedata(nid)				\
173 ({								\
174 	kzalloc(sizeof(pg_data_t), GFP_KERNEL);			\
175 })
176 /*
177  * This definition is just for error path in node hotadd.
178  * For node hotremove, we have to replace this.
179  */
180 #define generic_free_nodedata(pgdat)	kfree(pgdat)
181 
182 extern pg_data_t *node_data[];
183 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
184 {
185 	node_data[nid] = pgdat;
186 }
187 
188 #else /* !CONFIG_NUMA */
189 
190 /* never called */
191 static inline pg_data_t *generic_alloc_nodedata(int nid)
192 {
193 	BUG();
194 	return NULL;
195 }
196 static inline void generic_free_nodedata(pg_data_t *pgdat)
197 {
198 }
199 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
200 {
201 }
202 #endif /* CONFIG_NUMA */
203 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
204 
205 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
206 extern void __init register_page_bootmem_info_node(struct pglist_data *pgdat);
207 #else
208 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
209 {
210 }
211 #endif
212 extern void put_page_bootmem(struct page *page);
213 extern void get_page_bootmem(unsigned long ingo, struct page *page,
214 			     unsigned long type);
215 
216 void get_online_mems(void);
217 void put_online_mems(void);
218 
219 void mem_hotplug_begin(void);
220 void mem_hotplug_done(void);
221 
222 extern void set_zone_contiguous(struct zone *zone);
223 extern void clear_zone_contiguous(struct zone *zone);
224 
225 #else /* ! CONFIG_MEMORY_HOTPLUG */
226 #define pfn_to_online_page(pfn)			\
227 ({						\
228 	struct page *___page = NULL;		\
229 	if (pfn_valid(pfn))			\
230 		___page = pfn_to_page(pfn);	\
231 	___page;				\
232  })
233 
234 static inline unsigned zone_span_seqbegin(struct zone *zone)
235 {
236 	return 0;
237 }
238 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
239 {
240 	return 0;
241 }
242 static inline void zone_span_writelock(struct zone *zone) {}
243 static inline void zone_span_writeunlock(struct zone *zone) {}
244 static inline void zone_seqlock_init(struct zone *zone) {}
245 
246 static inline int mhp_notimplemented(const char *func)
247 {
248 	printk(KERN_WARNING "%s() called, with CONFIG_MEMORY_HOTPLUG disabled\n", func);
249 	dump_stack();
250 	return -ENOSYS;
251 }
252 
253 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
254 {
255 }
256 
257 static inline int try_online_node(int nid)
258 {
259 	return 0;
260 }
261 
262 static inline void get_online_mems(void) {}
263 static inline void put_online_mems(void) {}
264 
265 static inline void mem_hotplug_begin(void) {}
266 static inline void mem_hotplug_done(void) {}
267 
268 static inline bool movable_node_is_enabled(void)
269 {
270 	return false;
271 }
272 #endif /* ! CONFIG_MEMORY_HOTPLUG */
273 
274 #if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
275 /*
276  * pgdat resizing functions
277  */
278 static inline
279 void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
280 {
281 	spin_lock_irqsave(&pgdat->node_size_lock, *flags);
282 }
283 static inline
284 void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
285 {
286 	spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
287 }
288 static inline
289 void pgdat_resize_init(struct pglist_data *pgdat)
290 {
291 	spin_lock_init(&pgdat->node_size_lock);
292 }
293 #else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
294 /*
295  * Stub functions for when hotplug is off
296  */
297 static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
298 static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
299 static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
300 #endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
301 
302 #ifdef CONFIG_MEMORY_HOTREMOVE
303 
304 extern bool is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
305 extern void try_offline_node(int nid);
306 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
307 extern void remove_memory(int nid, u64 start, u64 size);
308 extern void __remove_memory(int nid, u64 start, u64 size);
309 
310 #else
311 static inline bool is_mem_section_removable(unsigned long pfn,
312 					unsigned long nr_pages)
313 {
314 	return false;
315 }
316 
317 static inline void try_offline_node(int nid) {}
318 
319 static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
320 {
321 	return -EINVAL;
322 }
323 
324 static inline void remove_memory(int nid, u64 start, u64 size) {}
325 static inline void __remove_memory(int nid, u64 start, u64 size) {}
326 #endif /* CONFIG_MEMORY_HOTREMOVE */
327 
328 extern void __ref free_area_init_core_hotplug(int nid);
329 extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
330 		void *arg, int (*func)(struct memory_block *, void *));
331 extern int __add_memory(int nid, u64 start, u64 size);
332 extern int add_memory(int nid, u64 start, u64 size);
333 extern int add_memory_resource(int nid, struct resource *resource);
334 extern int arch_add_memory(int nid, u64 start, u64 size,
335 		struct vmem_altmap *altmap, bool want_memblock);
336 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
337 		unsigned long nr_pages, struct vmem_altmap *altmap);
338 extern bool is_memblock_offlined(struct memory_block *mem);
339 extern int sparse_add_one_section(int nid, unsigned long start_pfn,
340 				  struct vmem_altmap *altmap);
341 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
342 		unsigned long map_offset, struct vmem_altmap *altmap);
343 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
344 					  unsigned long pnum);
345 extern bool allow_online_pfn_range(int nid, unsigned long pfn, unsigned long nr_pages,
346 		int online_type);
347 extern struct zone *zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
348 		unsigned long nr_pages);
349 #endif /* __LINUX_MEMORY_HOTPLUG_H */
350