xref: /linux/include/linux/memory_hotplug.h (revision 52338415)
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  * Restrictions for the memory hotplug:
58  * flags:  MHP_ flags
59  * altmap: alternative allocator for memmap array
60  */
61 struct mhp_restrictions {
62 	unsigned long flags;
63 	struct vmem_altmap *altmap;
64 };
65 
66 /*
67  * Zone resizing functions
68  *
69  * Note: any attempt to resize a zone should has pgdat_resize_lock()
70  * zone_span_writelock() both held. This ensure the size of a zone
71  * can't be changed while pgdat_resize_lock() held.
72  */
73 static inline unsigned zone_span_seqbegin(struct zone *zone)
74 {
75 	return read_seqbegin(&zone->span_seqlock);
76 }
77 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
78 {
79 	return read_seqretry(&zone->span_seqlock, iv);
80 }
81 static inline void zone_span_writelock(struct zone *zone)
82 {
83 	write_seqlock(&zone->span_seqlock);
84 }
85 static inline void zone_span_writeunlock(struct zone *zone)
86 {
87 	write_sequnlock(&zone->span_seqlock);
88 }
89 static inline void zone_seqlock_init(struct zone *zone)
90 {
91 	seqlock_init(&zone->span_seqlock);
92 }
93 extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages);
94 extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
95 extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
96 /* VM interface that may be used by firmware interface */
97 extern int online_pages(unsigned long, unsigned long, int);
98 extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
99 	unsigned long *valid_start, unsigned long *valid_end);
100 extern unsigned long __offline_isolated_pages(unsigned long start_pfn,
101 						unsigned long end_pfn);
102 
103 typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
104 
105 extern int set_online_page_callback(online_page_callback_t callback);
106 extern int restore_online_page_callback(online_page_callback_t callback);
107 
108 extern void __online_page_set_limits(struct page *page);
109 extern void __online_page_increment_counters(struct page *page);
110 extern void __online_page_free(struct page *page);
111 
112 extern int try_online_node(int nid);
113 
114 extern int arch_add_memory(int nid, u64 start, u64 size,
115 			struct mhp_restrictions *restrictions);
116 extern u64 max_mem_size;
117 
118 extern bool memhp_auto_online;
119 /* If movable_node boot option specified */
120 extern bool movable_node_enabled;
121 static inline bool movable_node_is_enabled(void)
122 {
123 	return movable_node_enabled;
124 }
125 
126 extern void arch_remove_memory(int nid, u64 start, u64 size,
127 			       struct vmem_altmap *altmap);
128 extern void __remove_pages(struct zone *zone, unsigned long start_pfn,
129 			   unsigned long nr_pages, struct vmem_altmap *altmap);
130 
131 /* reasonably generic interface to expand the physical pages */
132 extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
133 		       struct mhp_restrictions *restrictions);
134 
135 #ifndef CONFIG_ARCH_HAS_ADD_PAGES
136 static inline int add_pages(int nid, unsigned long start_pfn,
137 		unsigned long nr_pages, struct mhp_restrictions *restrictions)
138 {
139 	return __add_pages(nid, start_pfn, nr_pages, restrictions);
140 }
141 #else /* ARCH_HAS_ADD_PAGES */
142 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
143 	      struct mhp_restrictions *restrictions);
144 #endif /* ARCH_HAS_ADD_PAGES */
145 
146 #ifdef CONFIG_NUMA
147 extern int memory_add_physaddr_to_nid(u64 start);
148 #else
149 static inline int memory_add_physaddr_to_nid(u64 start)
150 {
151 	return 0;
152 }
153 #endif
154 
155 #ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
156 /*
157  * For supporting node-hotadd, we have to allocate a new pgdat.
158  *
159  * If an arch has generic style NODE_DATA(),
160  * node_data[nid] = kzalloc() works well. But it depends on the architecture.
161  *
162  * In general, generic_alloc_nodedata() is used.
163  * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
164  *
165  */
166 extern pg_data_t *arch_alloc_nodedata(int nid);
167 extern void arch_free_nodedata(pg_data_t *pgdat);
168 extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
169 
170 #else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
171 
172 #define arch_alloc_nodedata(nid)	generic_alloc_nodedata(nid)
173 #define arch_free_nodedata(pgdat)	generic_free_nodedata(pgdat)
174 
175 #ifdef CONFIG_NUMA
176 /*
177  * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
178  * XXX: kmalloc_node() can't work well to get new node's memory at this time.
179  *	Because, pgdat for the new node is not allocated/initialized yet itself.
180  *	To use new node's memory, more consideration will be necessary.
181  */
182 #define generic_alloc_nodedata(nid)				\
183 ({								\
184 	kzalloc(sizeof(pg_data_t), GFP_KERNEL);			\
185 })
186 /*
187  * This definition is just for error path in node hotadd.
188  * For node hotremove, we have to replace this.
189  */
190 #define generic_free_nodedata(pgdat)	kfree(pgdat)
191 
192 extern pg_data_t *node_data[];
193 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
194 {
195 	node_data[nid] = pgdat;
196 }
197 
198 #else /* !CONFIG_NUMA */
199 
200 /* never called */
201 static inline pg_data_t *generic_alloc_nodedata(int nid)
202 {
203 	BUG();
204 	return NULL;
205 }
206 static inline void generic_free_nodedata(pg_data_t *pgdat)
207 {
208 }
209 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
210 {
211 }
212 #endif /* CONFIG_NUMA */
213 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
214 
215 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
216 extern void __init register_page_bootmem_info_node(struct pglist_data *pgdat);
217 #else
218 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
219 {
220 }
221 #endif
222 extern void put_page_bootmem(struct page *page);
223 extern void get_page_bootmem(unsigned long ingo, struct page *page,
224 			     unsigned long type);
225 
226 void get_online_mems(void);
227 void put_online_mems(void);
228 
229 void mem_hotplug_begin(void);
230 void mem_hotplug_done(void);
231 
232 extern void set_zone_contiguous(struct zone *zone);
233 extern void clear_zone_contiguous(struct zone *zone);
234 
235 #else /* ! CONFIG_MEMORY_HOTPLUG */
236 #define pfn_to_online_page(pfn)			\
237 ({						\
238 	struct page *___page = NULL;		\
239 	if (pfn_valid(pfn))			\
240 		___page = pfn_to_page(pfn);	\
241 	___page;				\
242  })
243 
244 static inline unsigned zone_span_seqbegin(struct zone *zone)
245 {
246 	return 0;
247 }
248 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
249 {
250 	return 0;
251 }
252 static inline void zone_span_writelock(struct zone *zone) {}
253 static inline void zone_span_writeunlock(struct zone *zone) {}
254 static inline void zone_seqlock_init(struct zone *zone) {}
255 
256 static inline int mhp_notimplemented(const char *func)
257 {
258 	printk(KERN_WARNING "%s() called, with CONFIG_MEMORY_HOTPLUG disabled\n", func);
259 	dump_stack();
260 	return -ENOSYS;
261 }
262 
263 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
264 {
265 }
266 
267 static inline int try_online_node(int nid)
268 {
269 	return 0;
270 }
271 
272 static inline void get_online_mems(void) {}
273 static inline void put_online_mems(void) {}
274 
275 static inline void mem_hotplug_begin(void) {}
276 static inline void mem_hotplug_done(void) {}
277 
278 static inline bool movable_node_is_enabled(void)
279 {
280 	return false;
281 }
282 #endif /* ! CONFIG_MEMORY_HOTPLUG */
283 
284 #if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
285 /*
286  * pgdat resizing functions
287  */
288 static inline
289 void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
290 {
291 	spin_lock_irqsave(&pgdat->node_size_lock, *flags);
292 }
293 static inline
294 void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
295 {
296 	spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
297 }
298 static inline
299 void pgdat_resize_init(struct pglist_data *pgdat)
300 {
301 	spin_lock_init(&pgdat->node_size_lock);
302 }
303 #else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
304 /*
305  * Stub functions for when hotplug is off
306  */
307 static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
308 static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
309 static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
310 #endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
311 
312 #ifdef CONFIG_MEMORY_HOTREMOVE
313 
314 extern bool is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
315 extern void try_offline_node(int nid);
316 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
317 extern int remove_memory(int nid, u64 start, u64 size);
318 extern void __remove_memory(int nid, u64 start, u64 size);
319 
320 #else
321 static inline bool is_mem_section_removable(unsigned long pfn,
322 					unsigned long nr_pages)
323 {
324 	return false;
325 }
326 
327 static inline void try_offline_node(int nid) {}
328 
329 static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
330 {
331 	return -EINVAL;
332 }
333 
334 static inline int remove_memory(int nid, u64 start, u64 size)
335 {
336 	return -EBUSY;
337 }
338 
339 static inline void __remove_memory(int nid, u64 start, u64 size) {}
340 #endif /* CONFIG_MEMORY_HOTREMOVE */
341 
342 extern void __ref free_area_init_core_hotplug(int nid);
343 extern int __add_memory(int nid, u64 start, u64 size);
344 extern int add_memory(int nid, u64 start, u64 size);
345 extern int add_memory_resource(int nid, struct resource *resource);
346 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
347 		unsigned long nr_pages, struct vmem_altmap *altmap);
348 extern bool is_memblock_offlined(struct memory_block *mem);
349 extern int sparse_add_section(int nid, unsigned long pfn,
350 		unsigned long nr_pages, struct vmem_altmap *altmap);
351 extern void sparse_remove_section(struct mem_section *ms,
352 		unsigned long pfn, unsigned long nr_pages,
353 		unsigned long map_offset, struct vmem_altmap *altmap);
354 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
355 					  unsigned long pnum);
356 extern bool allow_online_pfn_range(int nid, unsigned long pfn, unsigned long nr_pages,
357 		int online_type);
358 extern struct zone *zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
359 		unsigned long nr_pages);
360 #endif /* __LINUX_MEMORY_HOTPLUG_H */
361