xref: /linux-6.15/include/linux/memory_hotplug.h (revision 7fcab099)
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.
17  * The normal smallest mapcount is -1. Here is smaller value than it.
18  */
19 #define SECTION_INFO		(-1 - 1)
20 #define MIX_SECTION_INFO	(-1 - 2)
21 #define NODE_INFO		(-1 - 3)
22 
23 /*
24  * pgdat resizing functions
25  */
26 static inline
27 void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
28 {
29 	spin_lock_irqsave(&pgdat->node_size_lock, *flags);
30 }
31 static inline
32 void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
33 {
34 	spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
35 }
36 static inline
37 void pgdat_resize_init(struct pglist_data *pgdat)
38 {
39 	spin_lock_init(&pgdat->node_size_lock);
40 }
41 /*
42  * Zone resizing functions
43  */
44 static inline unsigned zone_span_seqbegin(struct zone *zone)
45 {
46 	return read_seqbegin(&zone->span_seqlock);
47 }
48 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
49 {
50 	return read_seqretry(&zone->span_seqlock, iv);
51 }
52 static inline void zone_span_writelock(struct zone *zone)
53 {
54 	write_seqlock(&zone->span_seqlock);
55 }
56 static inline void zone_span_writeunlock(struct zone *zone)
57 {
58 	write_sequnlock(&zone->span_seqlock);
59 }
60 static inline void zone_seqlock_init(struct zone *zone)
61 {
62 	seqlock_init(&zone->span_seqlock);
63 }
64 extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages);
65 extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
66 extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
67 /* need some defines for these for archs that don't support it */
68 extern void online_page(struct page *page);
69 /* VM interface that may be used by firmware interface */
70 extern int online_pages(unsigned long, unsigned long);
71 extern void __offline_isolated_pages(unsigned long, unsigned long);
72 extern int offline_pages(unsigned long, unsigned long, unsigned long);
73 
74 /* reasonably generic interface to expand the physical pages in a zone  */
75 extern int __add_pages(int nid, struct zone *zone, unsigned long start_pfn,
76 	unsigned long nr_pages);
77 extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
78 	unsigned long nr_pages);
79 
80 #ifdef CONFIG_NUMA
81 extern int memory_add_physaddr_to_nid(u64 start);
82 #else
83 static inline int memory_add_physaddr_to_nid(u64 start)
84 {
85 	return 0;
86 }
87 #endif
88 
89 #ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
90 /*
91  * For supporting node-hotadd, we have to allocate a new pgdat.
92  *
93  * If an arch has generic style NODE_DATA(),
94  * node_data[nid] = kzalloc() works well. But it depends on the architecture.
95  *
96  * In general, generic_alloc_nodedata() is used.
97  * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
98  *
99  */
100 extern pg_data_t *arch_alloc_nodedata(int nid);
101 extern void arch_free_nodedata(pg_data_t *pgdat);
102 extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
103 
104 #else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
105 
106 #define arch_alloc_nodedata(nid)	generic_alloc_nodedata(nid)
107 #define arch_free_nodedata(pgdat)	generic_free_nodedata(pgdat)
108 
109 #ifdef CONFIG_NUMA
110 /*
111  * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
112  * XXX: kmalloc_node() can't work well to get new node's memory at this time.
113  *	Because, pgdat for the new node is not allocated/initialized yet itself.
114  *	To use new node's memory, more consideration will be necessary.
115  */
116 #define generic_alloc_nodedata(nid)				\
117 ({								\
118 	kzalloc(sizeof(pg_data_t), GFP_KERNEL);			\
119 })
120 /*
121  * This definition is just for error path in node hotadd.
122  * For node hotremove, we have to replace this.
123  */
124 #define generic_free_nodedata(pgdat)	kfree(pgdat)
125 
126 extern pg_data_t *node_data[];
127 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
128 {
129 	node_data[nid] = pgdat;
130 }
131 
132 #else /* !CONFIG_NUMA */
133 
134 /* never called */
135 static inline pg_data_t *generic_alloc_nodedata(int nid)
136 {
137 	BUG();
138 	return NULL;
139 }
140 static inline void generic_free_nodedata(pg_data_t *pgdat)
141 {
142 }
143 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
144 {
145 }
146 #endif /* CONFIG_NUMA */
147 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
148 
149 #ifdef CONFIG_SPARSEMEM_VMEMMAP
150 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
151 {
152 }
153 static inline void put_page_bootmem(struct page *page)
154 {
155 }
156 #else
157 extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
158 extern void put_page_bootmem(struct page *page);
159 #endif
160 
161 #else /* ! CONFIG_MEMORY_HOTPLUG */
162 /*
163  * Stub functions for when hotplug is off
164  */
165 static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
166 static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
167 static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
168 
169 static inline unsigned zone_span_seqbegin(struct zone *zone)
170 {
171 	return 0;
172 }
173 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
174 {
175 	return 0;
176 }
177 static inline void zone_span_writelock(struct zone *zone) {}
178 static inline void zone_span_writeunlock(struct zone *zone) {}
179 static inline void zone_seqlock_init(struct zone *zone) {}
180 
181 static inline int mhp_notimplemented(const char *func)
182 {
183 	printk(KERN_WARNING "%s() called, with CONFIG_MEMORY_HOTPLUG disabled\n", func);
184 	dump_stack();
185 	return -ENOSYS;
186 }
187 
188 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
189 {
190 }
191 
192 #endif /* ! CONFIG_MEMORY_HOTPLUG */
193 
194 /*
195  * Walk through all memory which is registered as resource.
196  * arg is (start_pfn, nr_pages, private_arg_pointer)
197  */
198 extern int walk_memory_resource(unsigned long start_pfn,
199 			unsigned long nr_pages, void *arg,
200 			int (*func)(unsigned long, unsigned long, void *));
201 
202 #ifdef CONFIG_MEMORY_HOTREMOVE
203 
204 extern int is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
205 
206 #else
207 static inline int is_mem_section_removable(unsigned long pfn,
208 					unsigned long nr_pages)
209 {
210 	return 0;
211 }
212 #endif /* CONFIG_MEMORY_HOTREMOVE */
213 
214 extern int add_memory(int nid, u64 start, u64 size);
215 extern int arch_add_memory(int nid, u64 start, u64 size);
216 extern int remove_memory(u64 start, u64 size);
217 extern int sparse_add_one_section(struct zone *zone, unsigned long start_pfn,
218 								int nr_pages);
219 extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms);
220 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
221 					  unsigned long pnum);
222 
223 #endif /* __LINUX_MEMORY_HOTPLUG_H */
224