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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
10struct page;
11struct zone;
12struct pglist_data;
13struct mem_section;
14struct memory_block;
15struct resource;
16struct vmem_altmap;
17
18#ifdef CONFIG_MEMORY_HOTPLUG
19struct page *pfn_to_online_page(unsigned long pfn);
20
21/* Types for control the zone type of onlined and offlined memory */
22enum {
23 /* Offline the memory. */
24 MMOP_OFFLINE = 0,
25 /* Online the memory. Zone depends, see default_zone_for_pfn(). */
26 MMOP_ONLINE,
27 /* Online the memory to ZONE_NORMAL. */
28 MMOP_ONLINE_KERNEL,
29 /* Online the memory to ZONE_MOVABLE. */
30 MMOP_ONLINE_MOVABLE,
31};
32
33/* Flags for add_memory() and friends to specify memory hotplug details. */
34typedef int __bitwise mhp_t;
35
36/* No special request */
37#define MHP_NONE ((__force mhp_t)0)
38/*
39 * Allow merging of the added System RAM resource with adjacent,
40 * mergeable resources. After a successful call to add_memory_resource()
41 * with this flag set, the resource pointer must no longer be used as it
42 * might be stale, or the resource might have changed.
43 */
44#define MHP_MERGE_RESOURCE ((__force mhp_t)BIT(0))
45
46/*
47 * We want memmap (struct page array) to be self contained.
48 * To do so, we will use the beginning of the hot-added range to build
49 * the page tables for the memmap array that describes the entire range.
50 * Only selected architectures support it with SPARSE_VMEMMAP.
51 */
52#define MHP_MEMMAP_ON_MEMORY ((__force mhp_t)BIT(1))
53
54/*
55 * Extended parameters for memory hotplug:
56 * altmap: alternative allocator for memmap array (optional)
57 * pgprot: page protection flags to apply to newly created page tables
58 * (required)
59 */
60struct mhp_params {
61 struct vmem_altmap *altmap;
62 pgprot_t pgprot;
63};
64
65bool mhp_range_allowed(u64 start, u64 size, bool need_mapping);
66struct range mhp_get_pluggable_range(bool need_mapping);
67
68/*
69 * Zone resizing functions
70 *
71 * Note: any attempt to resize a zone should has pgdat_resize_lock()
72 * zone_span_writelock() both held. This ensure the size of a zone
73 * can't be changed while pgdat_resize_lock() held.
74 */
75static inline unsigned zone_span_seqbegin(struct zone *zone)
76{
77 return read_seqbegin(&zone->span_seqlock);
78}
79static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
80{
81 return read_seqretry(&zone->span_seqlock, iv);
82}
83static inline void zone_span_writelock(struct zone *zone)
84{
85 write_seqlock(&zone->span_seqlock);
86}
87static inline void zone_span_writeunlock(struct zone *zone)
88{
89 write_sequnlock(&zone->span_seqlock);
90}
91static inline void zone_seqlock_init(struct zone *zone)
92{
93 seqlock_init(&zone->span_seqlock);
94}
95extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages);
96extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
97extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
98extern void adjust_present_page_count(struct zone *zone, long nr_pages);
99/* VM interface that may be used by firmware interface */
100extern int mhp_init_memmap_on_memory(unsigned long pfn, unsigned long nr_pages,
101 struct zone *zone);
102extern void mhp_deinit_memmap_on_memory(unsigned long pfn, unsigned long nr_pages);
103extern int online_pages(unsigned long pfn, unsigned long nr_pages,
104 struct zone *zone);
105extern struct zone *test_pages_in_a_zone(unsigned long start_pfn,
106 unsigned long end_pfn);
107extern void __offline_isolated_pages(unsigned long start_pfn,
108 unsigned long end_pfn);
109
110typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
111
112extern void generic_online_page(struct page *page, unsigned int order);
113extern int set_online_page_callback(online_page_callback_t callback);
114extern int restore_online_page_callback(online_page_callback_t callback);
115
116extern int try_online_node(int nid);
117
118extern int arch_add_memory(int nid, u64 start, u64 size,
119 struct mhp_params *params);
120extern u64 max_mem_size;
121
122extern int mhp_online_type_from_str(const char *str);
123
124/* Default online_type (MMOP_*) when new memory blocks are added. */
125extern int mhp_default_online_type;
126/* If movable_node boot option specified */
127extern bool movable_node_enabled;
128static inline bool movable_node_is_enabled(void)
129{
130 return movable_node_enabled;
131}
132
133extern void arch_remove_memory(int nid, u64 start, u64 size,
134 struct vmem_altmap *altmap);
135extern void __remove_pages(unsigned long start_pfn, unsigned long nr_pages,
136 struct vmem_altmap *altmap);
137
138/* reasonably generic interface to expand the physical pages */
139extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
140 struct mhp_params *params);
141
142#ifndef CONFIG_ARCH_HAS_ADD_PAGES
143static inline int add_pages(int nid, unsigned long start_pfn,
144 unsigned long nr_pages, struct mhp_params *params)
145{
146 return __add_pages(nid, start_pfn, nr_pages, params);
147}
148#else /* ARCH_HAS_ADD_PAGES */
149int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
150 struct mhp_params *params);
151#endif /* ARCH_HAS_ADD_PAGES */
152
153#ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
154/*
155 * For supporting node-hotadd, we have to allocate a new pgdat.
156 *
157 * If an arch has generic style NODE_DATA(),
158 * node_data[nid] = kzalloc() works well. But it depends on the architecture.
159 *
160 * In general, generic_alloc_nodedata() is used.
161 * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
162 *
163 */
164extern pg_data_t *arch_alloc_nodedata(int nid);
165extern void arch_free_nodedata(pg_data_t *pgdat);
166extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
167
168#else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
169
170#define arch_alloc_nodedata(nid) generic_alloc_nodedata(nid)
171#define arch_free_nodedata(pgdat) generic_free_nodedata(pgdat)
172
173#ifdef CONFIG_NUMA
174/*
175 * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
176 * XXX: kmalloc_node() can't work well to get new node's memory at this time.
177 * Because, pgdat for the new node is not allocated/initialized yet itself.
178 * To use new node's memory, more consideration will be necessary.
179 */
180#define generic_alloc_nodedata(nid) \
181({ \
182 kzalloc(sizeof(pg_data_t), GFP_KERNEL); \
183})
184/*
185 * This definition is just for error path in node hotadd.
186 * For node hotremove, we have to replace this.
187 */
188#define generic_free_nodedata(pgdat) kfree(pgdat)
189
190extern pg_data_t *node_data[];
191static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
192{
193 node_data[nid] = pgdat;
194}
195
196#else /* !CONFIG_NUMA */
197
198/* never called */
199static inline pg_data_t *generic_alloc_nodedata(int nid)
200{
201 BUG();
202 return NULL;
203}
204static inline void generic_free_nodedata(pg_data_t *pgdat)
205{
206}
207static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
208{
209}
210#endif /* CONFIG_NUMA */
211#endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
212
213void get_online_mems(void);
214void put_online_mems(void);
215
216void mem_hotplug_begin(void);
217void mem_hotplug_done(void);
218
219#else /* ! CONFIG_MEMORY_HOTPLUG */
220#define pfn_to_online_page(pfn) \
221({ \
222 struct page *___page = NULL; \
223 if (pfn_valid(pfn)) \
224 ___page = pfn_to_page(pfn); \
225 ___page; \
226 })
227
228static inline unsigned zone_span_seqbegin(struct zone *zone)
229{
230 return 0;
231}
232static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
233{
234 return 0;
235}
236static inline void zone_span_writelock(struct zone *zone) {}
237static inline void zone_span_writeunlock(struct zone *zone) {}
238static inline void zone_seqlock_init(struct zone *zone) {}
239
240static inline int try_online_node(int nid)
241{
242 return 0;
243}
244
245static inline void get_online_mems(void) {}
246static inline void put_online_mems(void) {}
247
248static inline void mem_hotplug_begin(void) {}
249static inline void mem_hotplug_done(void) {}
250
251static inline bool movable_node_is_enabled(void)
252{
253 return false;
254}
255#endif /* ! CONFIG_MEMORY_HOTPLUG */
256
257/*
258 * Keep this declaration outside CONFIG_MEMORY_HOTPLUG as some
259 * platforms might override and use arch_get_mappable_range()
260 * for internal non memory hotplug purposes.
261 */
262struct range arch_get_mappable_range(void);
263
264#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
265/*
266 * pgdat resizing functions
267 */
268static inline
269void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
270{
271 spin_lock_irqsave(&pgdat->node_size_lock, *flags);
272}
273static inline
274void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
275{
276 spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
277}
278static inline
279void pgdat_resize_init(struct pglist_data *pgdat)
280{
281 spin_lock_init(&pgdat->node_size_lock);
282}
283#else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
284/*
285 * Stub functions for when hotplug is off
286 */
287static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
288static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
289static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
290#endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
291
292#ifdef CONFIG_MEMORY_HOTREMOVE
293
294extern void try_offline_node(int nid);
295extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
296extern int remove_memory(int nid, u64 start, u64 size);
297extern void __remove_memory(int nid, u64 start, u64 size);
298extern int offline_and_remove_memory(int nid, u64 start, u64 size);
299
300#else
301static inline void try_offline_node(int nid) {}
302
303static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
304{
305 return -EINVAL;
306}
307
308static inline int remove_memory(int nid, u64 start, u64 size)
309{
310 return -EBUSY;
311}
312
313static inline void __remove_memory(int nid, u64 start, u64 size) {}
314#endif /* CONFIG_MEMORY_HOTREMOVE */
315
316extern void set_zone_contiguous(struct zone *zone);
317extern void clear_zone_contiguous(struct zone *zone);
318
319#ifdef CONFIG_MEMORY_HOTPLUG
320extern void __ref free_area_init_core_hotplug(int nid);
321extern int __add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
322extern int add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
323extern int add_memory_resource(int nid, struct resource *resource,
324 mhp_t mhp_flags);
325extern int add_memory_driver_managed(int nid, u64 start, u64 size,
326 const char *resource_name,
327 mhp_t mhp_flags);
328extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
329 unsigned long nr_pages,
330 struct vmem_altmap *altmap, int migratetype);
331extern void remove_pfn_range_from_zone(struct zone *zone,
332 unsigned long start_pfn,
333 unsigned long nr_pages);
334extern bool is_memblock_offlined(struct memory_block *mem);
335extern int sparse_add_section(int nid, unsigned long pfn,
336 unsigned long nr_pages, struct vmem_altmap *altmap);
337extern void sparse_remove_section(struct mem_section *ms,
338 unsigned long pfn, unsigned long nr_pages,
339 unsigned long map_offset, struct vmem_altmap *altmap);
340extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
341 unsigned long pnum);
342extern struct zone *zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
343 unsigned long nr_pages);
344extern int arch_create_linear_mapping(int nid, u64 start, u64 size,
345 struct mhp_params *params);
346void arch_remove_linear_mapping(u64 start, u64 size);
347extern bool mhp_supports_memmap_on_memory(unsigned long size);
348#endif /* CONFIG_MEMORY_HOTPLUG */
349
350#endif /* __LINUX_MEMORY_HOTPLUG_H */