xref: /linux-6.15/include/linux/memory_hotplug.h (revision c54ea491)
1 #ifndef __LINUX_MEMORY_HOTPLUG_H
2 #define __LINUX_MEMORY_HOTPLUG_H
3 
4 #include <linux/mmzone.h>
5 #include <linux/spinlock.h>
6 #include <linux/notifier.h>
7 
8 struct page;
9 struct zone;
10 struct pglist_data;
11 struct mem_section;
12 
13 #ifdef CONFIG_MEMORY_HOTPLUG
14 
15 /*
16  * Types for free bootmem stored in page->lru.next. These have to be in
17  * some random range in unsigned long space for debugging purposes.
18  */
19 enum {
20 	MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE = 12,
21 	SECTION_INFO = MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE,
22 	MIX_SECTION_INFO,
23 	NODE_INFO,
24 	MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE = NODE_INFO,
25 };
26 
27 /*
28  * pgdat resizing functions
29  */
30 static inline
31 void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
32 {
33 	spin_lock_irqsave(&pgdat->node_size_lock, *flags);
34 }
35 static inline
36 void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
37 {
38 	spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
39 }
40 static inline
41 void pgdat_resize_init(struct pglist_data *pgdat)
42 {
43 	spin_lock_init(&pgdat->node_size_lock);
44 }
45 /*
46  * Zone resizing functions
47  */
48 static inline unsigned zone_span_seqbegin(struct zone *zone)
49 {
50 	return read_seqbegin(&zone->span_seqlock);
51 }
52 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
53 {
54 	return read_seqretry(&zone->span_seqlock, iv);
55 }
56 static inline void zone_span_writelock(struct zone *zone)
57 {
58 	write_seqlock(&zone->span_seqlock);
59 }
60 static inline void zone_span_writeunlock(struct zone *zone)
61 {
62 	write_sequnlock(&zone->span_seqlock);
63 }
64 static inline void zone_seqlock_init(struct zone *zone)
65 {
66 	seqlock_init(&zone->span_seqlock);
67 }
68 extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages);
69 extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
70 extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
71 /* need some defines for these for archs that don't support it */
72 extern void online_page(struct page *page);
73 /* VM interface that may be used by firmware interface */
74 extern int online_pages(unsigned long, unsigned long);
75 extern void __offline_isolated_pages(unsigned long, unsigned long);
76 
77 #ifdef CONFIG_MEMORY_HOTREMOVE
78 extern bool is_pageblock_removable_nolock(struct page *page);
79 #endif /* CONFIG_MEMORY_HOTREMOVE */
80 
81 /* reasonably generic interface to expand the physical pages in a zone  */
82 extern int __add_pages(int nid, struct zone *zone, unsigned long start_pfn,
83 	unsigned long nr_pages);
84 extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
85 	unsigned long nr_pages);
86 
87 #ifdef CONFIG_NUMA
88 extern int memory_add_physaddr_to_nid(u64 start);
89 #else
90 static inline int memory_add_physaddr_to_nid(u64 start)
91 {
92 	return 0;
93 }
94 #endif
95 
96 #ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
97 /*
98  * For supporting node-hotadd, we have to allocate a new pgdat.
99  *
100  * If an arch has generic style NODE_DATA(),
101  * node_data[nid] = kzalloc() works well. But it depends on the architecture.
102  *
103  * In general, generic_alloc_nodedata() is used.
104  * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
105  *
106  */
107 extern pg_data_t *arch_alloc_nodedata(int nid);
108 extern void arch_free_nodedata(pg_data_t *pgdat);
109 extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
110 
111 #else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
112 
113 #define arch_alloc_nodedata(nid)	generic_alloc_nodedata(nid)
114 #define arch_free_nodedata(pgdat)	generic_free_nodedata(pgdat)
115 
116 #ifdef CONFIG_NUMA
117 /*
118  * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
119  * XXX: kmalloc_node() can't work well to get new node's memory at this time.
120  *	Because, pgdat for the new node is not allocated/initialized yet itself.
121  *	To use new node's memory, more consideration will be necessary.
122  */
123 #define generic_alloc_nodedata(nid)				\
124 ({								\
125 	kzalloc(sizeof(pg_data_t), GFP_KERNEL);			\
126 })
127 /*
128  * This definition is just for error path in node hotadd.
129  * For node hotremove, we have to replace this.
130  */
131 #define generic_free_nodedata(pgdat)	kfree(pgdat)
132 
133 extern pg_data_t *node_data[];
134 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
135 {
136 	node_data[nid] = pgdat;
137 }
138 
139 #else /* !CONFIG_NUMA */
140 
141 /* never called */
142 static inline pg_data_t *generic_alloc_nodedata(int nid)
143 {
144 	BUG();
145 	return NULL;
146 }
147 static inline void generic_free_nodedata(pg_data_t *pgdat)
148 {
149 }
150 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
151 {
152 }
153 #endif /* CONFIG_NUMA */
154 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
155 
156 #ifdef CONFIG_SPARSEMEM_VMEMMAP
157 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
158 {
159 }
160 static inline void put_page_bootmem(struct page *page)
161 {
162 }
163 #else
164 extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
165 extern void put_page_bootmem(struct page *page);
166 #endif
167 
168 /*
169  * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug
170  * notifier will be called under this. 2) offline/online/add/remove memory
171  * will not run simultaneously.
172  */
173 
174 void lock_memory_hotplug(void);
175 void unlock_memory_hotplug(void);
176 
177 #else /* ! CONFIG_MEMORY_HOTPLUG */
178 /*
179  * Stub functions for when hotplug is off
180  */
181 static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
182 static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
183 static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
184 
185 static inline unsigned zone_span_seqbegin(struct zone *zone)
186 {
187 	return 0;
188 }
189 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
190 {
191 	return 0;
192 }
193 static inline void zone_span_writelock(struct zone *zone) {}
194 static inline void zone_span_writeunlock(struct zone *zone) {}
195 static inline void zone_seqlock_init(struct zone *zone) {}
196 
197 static inline int mhp_notimplemented(const char *func)
198 {
199 	printk(KERN_WARNING "%s() called, with CONFIG_MEMORY_HOTPLUG disabled\n", func);
200 	dump_stack();
201 	return -ENOSYS;
202 }
203 
204 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
205 {
206 }
207 
208 static inline void lock_memory_hotplug(void) {}
209 static inline void unlock_memory_hotplug(void) {}
210 
211 #endif /* ! CONFIG_MEMORY_HOTPLUG */
212 
213 #ifdef CONFIG_MEMORY_HOTREMOVE
214 
215 extern int is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
216 
217 #else
218 static inline int is_mem_section_removable(unsigned long pfn,
219 					unsigned long nr_pages)
220 {
221 	return 0;
222 }
223 #endif /* CONFIG_MEMORY_HOTREMOVE */
224 
225 extern int mem_online_node(int nid);
226 extern int add_memory(int nid, u64 start, u64 size);
227 extern int arch_add_memory(int nid, u64 start, u64 size);
228 extern int remove_memory(u64 start, u64 size);
229 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
230 								int nr_pages);
231 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms);
232 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
233 					  unsigned long pnum);
234 
235 #endif /* __LINUX_MEMORY_HOTPLUG_H */
236