1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_MEMORY_HOTPLUG_H
3 #define __LINUX_MEMORY_HOTPLUG_H
5 #include <linux/mmzone.h>
6 #include <linux/spinlock.h>
7 #include <linux/notifier.h>
19 #ifdef CONFIG_MEMORY_HOTPLUG
20 struct page *pfn_to_online_page(unsigned long pfn);
22 /* Types for control the zone type of onlined and offlined memory */
24 /* Offline the memory. */
26 /* Online the memory. Zone depends, see default_zone_for_pfn(). */
28 /* Online the memory to ZONE_NORMAL. */
30 /* Online the memory to ZONE_MOVABLE. */
34 /* Flags for add_memory() and friends to specify memory hotplug details. */
35 typedef int __bitwise mhp_t;
37 /* No special request */
38 #define MHP_NONE ((__force mhp_t)0)
40 * Allow merging of the added System RAM resource with adjacent,
41 * mergeable resources. After a successful call to add_memory_resource()
42 * with this flag set, the resource pointer must no longer be used as it
43 * might be stale, or the resource might have changed.
45 #define MHP_MERGE_RESOURCE ((__force mhp_t)BIT(0))
48 * We want memmap (struct page array) to be self contained.
49 * To do so, we will use the beginning of the hot-added range to build
50 * the page tables for the memmap array that describes the entire range.
51 * Only selected architectures support it with SPARSE_VMEMMAP.
53 #define MHP_MEMMAP_ON_MEMORY ((__force mhp_t)BIT(1))
55 * The nid field specifies a memory group id (mgid) instead. The memory group
56 * implies the node id (nid).
58 #define MHP_NID_IS_MGID ((__force mhp_t)BIT(2))
61 * Extended parameters for memory hotplug:
62 * altmap: alternative allocator for memmap array (optional)
63 * pgprot: page protection flags to apply to newly created page tables
67 struct vmem_altmap *altmap;
71 bool mhp_range_allowed(u64 start, u64 size, bool need_mapping);
72 struct range mhp_get_pluggable_range(bool need_mapping);
75 * Zone resizing functions
77 * Note: any attempt to resize a zone should has pgdat_resize_lock()
78 * zone_span_writelock() both held. This ensure the size of a zone
79 * can't be changed while pgdat_resize_lock() held.
81 static inline unsigned zone_span_seqbegin(struct zone *zone)
83 return read_seqbegin(&zone->span_seqlock);
85 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
87 return read_seqretry(&zone->span_seqlock, iv);
89 static inline void zone_span_writelock(struct zone *zone)
91 write_seqlock(&zone->span_seqlock);
93 static inline void zone_span_writeunlock(struct zone *zone)
95 write_sequnlock(&zone->span_seqlock);
97 static inline void zone_seqlock_init(struct zone *zone)
99 seqlock_init(&zone->span_seqlock);
101 extern void adjust_present_page_count(struct page *page,
102 struct memory_group *group,
104 /* VM interface that may be used by firmware interface */
105 extern int mhp_init_memmap_on_memory(unsigned long pfn, unsigned long nr_pages,
107 extern void mhp_deinit_memmap_on_memory(unsigned long pfn, unsigned long nr_pages);
108 extern int online_pages(unsigned long pfn, unsigned long nr_pages,
109 struct zone *zone, struct memory_group *group);
110 extern struct zone *test_pages_in_a_zone(unsigned long start_pfn,
111 unsigned long end_pfn);
112 extern void __offline_isolated_pages(unsigned long start_pfn,
113 unsigned long end_pfn);
115 typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
117 extern void generic_online_page(struct page *page, unsigned int order);
118 extern int set_online_page_callback(online_page_callback_t callback);
119 extern int restore_online_page_callback(online_page_callback_t callback);
121 extern int try_online_node(int nid);
123 extern int arch_add_memory(int nid, u64 start, u64 size,
124 struct mhp_params *params);
125 extern u64 max_mem_size;
127 extern int mhp_online_type_from_str(const char *str);
129 /* Default online_type (MMOP_*) when new memory blocks are added. */
130 extern int mhp_default_online_type;
131 /* If movable_node boot option specified */
132 extern bool movable_node_enabled;
133 static inline bool movable_node_is_enabled(void)
135 return movable_node_enabled;
138 extern void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap);
139 extern void __remove_pages(unsigned long start_pfn, unsigned long nr_pages,
140 struct vmem_altmap *altmap);
142 /* reasonably generic interface to expand the physical pages */
143 extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
144 struct mhp_params *params);
146 #ifndef CONFIG_ARCH_HAS_ADD_PAGES
147 static inline int add_pages(int nid, unsigned long start_pfn,
148 unsigned long nr_pages, struct mhp_params *params)
150 return __add_pages(nid, start_pfn, nr_pages, params);
152 #else /* ARCH_HAS_ADD_PAGES */
153 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
154 struct mhp_params *params);
155 #endif /* ARCH_HAS_ADD_PAGES */
157 #ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
159 * For supporting node-hotadd, we have to allocate a new pgdat.
161 * If an arch has generic style NODE_DATA(),
162 * node_data[nid] = kzalloc() works well. But it depends on the architecture.
164 * In general, generic_alloc_nodedata() is used.
165 * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
168 extern pg_data_t *arch_alloc_nodedata(int nid);
169 extern void arch_free_nodedata(pg_data_t *pgdat);
170 extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
172 #else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
174 #define arch_alloc_nodedata(nid) generic_alloc_nodedata(nid)
175 #define arch_free_nodedata(pgdat) generic_free_nodedata(pgdat)
179 * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
180 * XXX: kmalloc_node() can't work well to get new node's memory at this time.
181 * Because, pgdat for the new node is not allocated/initialized yet itself.
182 * To use new node's memory, more consideration will be necessary.
184 #define generic_alloc_nodedata(nid) \
186 kzalloc(sizeof(pg_data_t), GFP_KERNEL); \
189 * This definition is just for error path in node hotadd.
190 * For node hotremove, we have to replace this.
192 #define generic_free_nodedata(pgdat) kfree(pgdat)
194 extern pg_data_t *node_data[];
195 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
197 node_data[nid] = pgdat;
200 #else /* !CONFIG_NUMA */
203 static inline pg_data_t *generic_alloc_nodedata(int nid)
208 static inline void generic_free_nodedata(pg_data_t *pgdat)
211 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
214 #endif /* CONFIG_NUMA */
215 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
217 void get_online_mems(void);
218 void put_online_mems(void);
220 void mem_hotplug_begin(void);
221 void mem_hotplug_done(void);
223 #else /* ! CONFIG_MEMORY_HOTPLUG */
224 #define pfn_to_online_page(pfn) \
226 struct page *___page = NULL; \
227 if (pfn_valid(pfn)) \
228 ___page = pfn_to_page(pfn); \
232 static inline unsigned zone_span_seqbegin(struct zone *zone)
236 static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
240 static inline void zone_span_writelock(struct zone *zone) {}
241 static inline void zone_span_writeunlock(struct zone *zone) {}
242 static inline void zone_seqlock_init(struct zone *zone) {}
244 static inline int try_online_node(int nid)
249 static inline void get_online_mems(void) {}
250 static inline void put_online_mems(void) {}
252 static inline void mem_hotplug_begin(void) {}
253 static inline void mem_hotplug_done(void) {}
255 static inline bool movable_node_is_enabled(void)
259 #endif /* ! CONFIG_MEMORY_HOTPLUG */
262 * Keep this declaration outside CONFIG_MEMORY_HOTPLUG as some
263 * platforms might override and use arch_get_mappable_range()
264 * for internal non memory hotplug purposes.
266 struct range arch_get_mappable_range(void);
268 #if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
270 * pgdat resizing functions
273 void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
275 spin_lock_irqsave(&pgdat->node_size_lock, *flags);
278 void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
280 spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
283 void pgdat_resize_init(struct pglist_data *pgdat)
285 spin_lock_init(&pgdat->node_size_lock);
287 #else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
289 * Stub functions for when hotplug is off
291 static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
292 static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
293 static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
294 #endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
296 #ifdef CONFIG_MEMORY_HOTREMOVE
298 extern void try_offline_node(int nid);
299 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages,
300 struct memory_group *group);
301 extern int remove_memory(u64 start, u64 size);
302 extern void __remove_memory(u64 start, u64 size);
303 extern int offline_and_remove_memory(u64 start, u64 size);
306 static inline void try_offline_node(int nid) {}
308 static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages,
309 struct memory_group *group)
314 static inline int remove_memory(u64 start, u64 size)
319 static inline void __remove_memory(u64 start, u64 size) {}
320 #endif /* CONFIG_MEMORY_HOTREMOVE */
322 extern void set_zone_contiguous(struct zone *zone);
323 extern void clear_zone_contiguous(struct zone *zone);
325 #ifdef CONFIG_MEMORY_HOTPLUG
326 extern void __ref free_area_init_core_hotplug(int nid);
327 extern int __add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
328 extern int add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
329 extern int add_memory_resource(int nid, struct resource *resource,
331 extern int add_memory_driver_managed(int nid, u64 start, u64 size,
332 const char *resource_name,
334 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
335 unsigned long nr_pages,
336 struct vmem_altmap *altmap, int migratetype);
337 extern void remove_pfn_range_from_zone(struct zone *zone,
338 unsigned long start_pfn,
339 unsigned long nr_pages);
340 extern bool is_memblock_offlined(struct memory_block *mem);
341 extern int sparse_add_section(int nid, unsigned long pfn,
342 unsigned long nr_pages, struct vmem_altmap *altmap);
343 extern void sparse_remove_section(struct mem_section *ms,
344 unsigned long pfn, unsigned long nr_pages,
345 unsigned long map_offset, struct vmem_altmap *altmap);
346 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
348 extern struct zone *zone_for_pfn_range(int online_type, int nid,
349 struct memory_group *group, unsigned long start_pfn,
350 unsigned long nr_pages);
351 extern int arch_create_linear_mapping(int nid, u64 start, u64 size,
352 struct mhp_params *params);
353 void arch_remove_linear_mapping(u64 start, u64 size);
354 extern bool mhp_supports_memmap_on_memory(unsigned long size);
355 #endif /* CONFIG_MEMORY_HOTPLUG */
357 #endif /* __LINUX_MEMORY_HOTPLUG_H */