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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 memory_group;
16struct resource;
17struct vmem_altmap;
18
19#ifdef CONFIG_MEMORY_HOTPLUG
20struct page *pfn_to_online_page(unsigned long pfn);
21
22/* Types for control the zone type of onlined and offlined memory */
23enum {
24 /* Offline the memory. */
25 MMOP_OFFLINE = 0,
26 /* Online the memory. Zone depends, see default_zone_for_pfn(). */
27 MMOP_ONLINE,
28 /* Online the memory to ZONE_NORMAL. */
29 MMOP_ONLINE_KERNEL,
30 /* Online the memory to ZONE_MOVABLE. */
31 MMOP_ONLINE_MOVABLE,
32};
33
34/* Flags for add_memory() and friends to specify memory hotplug details. */
35typedef int __bitwise mhp_t;
36
37/* No special request */
38#define MHP_NONE ((__force mhp_t)0)
39/*
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.
44 */
45#define MHP_MERGE_RESOURCE ((__force mhp_t)BIT(0))
46
47/*
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.
52 */
53#define MHP_MEMMAP_ON_MEMORY ((__force mhp_t)BIT(1))
54/*
55 * The nid field specifies a memory group id (mgid) instead. The memory group
56 * implies the node id (nid).
57 */
58#define MHP_NID_IS_MGID ((__force mhp_t)BIT(2))
59
60/*
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
64 * (required)
65 */
66struct mhp_params {
67 struct vmem_altmap *altmap;
68 pgprot_t pgprot;
69};
70
71bool mhp_range_allowed(u64 start, u64 size, bool need_mapping);
72struct range mhp_get_pluggable_range(bool need_mapping);
73
74/*
75 * Zone resizing functions
76 *
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.
80 */
81static inline unsigned zone_span_seqbegin(struct zone *zone)
82{
83 return read_seqbegin(&zone->span_seqlock);
84}
85static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
86{
87 return read_seqretry(&zone->span_seqlock, iv);
88}
89static inline void zone_span_writelock(struct zone *zone)
90{
91 write_seqlock(&zone->span_seqlock);
92}
93static inline void zone_span_writeunlock(struct zone *zone)
94{
95 write_sequnlock(&zone->span_seqlock);
96}
97static inline void zone_seqlock_init(struct zone *zone)
98{
99 seqlock_init(&zone->span_seqlock);
100}
101extern void adjust_present_page_count(struct page *page,
102 struct memory_group *group,
103 long nr_pages);
104/* VM interface that may be used by firmware interface */
105extern int mhp_init_memmap_on_memory(unsigned long pfn, unsigned long nr_pages,
106 struct zone *zone);
107extern void mhp_deinit_memmap_on_memory(unsigned long pfn, unsigned long nr_pages);
108extern int online_pages(unsigned long pfn, unsigned long nr_pages,
109 struct zone *zone, struct memory_group *group);
110extern struct zone *test_pages_in_a_zone(unsigned long start_pfn,
111 unsigned long end_pfn);
112extern void __offline_isolated_pages(unsigned long start_pfn,
113 unsigned long end_pfn);
114
115typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
116
117extern void generic_online_page(struct page *page, unsigned int order);
118extern int set_online_page_callback(online_page_callback_t callback);
119extern int restore_online_page_callback(online_page_callback_t callback);
120
121extern int try_online_node(int nid);
122
123extern int arch_add_memory(int nid, u64 start, u64 size,
124 struct mhp_params *params);
125extern u64 max_mem_size;
126
127extern int mhp_online_type_from_str(const char *str);
128
129/* Default online_type (MMOP_*) when new memory blocks are added. */
130extern int mhp_default_online_type;
131/* If movable_node boot option specified */
132extern bool movable_node_enabled;
133static inline bool movable_node_is_enabled(void)
134{
135 return movable_node_enabled;
136}
137
138extern void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap);
139extern void __remove_pages(unsigned long start_pfn, unsigned long nr_pages,
140 struct vmem_altmap *altmap);
141
142/* reasonably generic interface to expand the physical pages */
143extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
144 struct mhp_params *params);
145
146#ifndef CONFIG_ARCH_HAS_ADD_PAGES
147static inline int add_pages(int nid, unsigned long start_pfn,
148 unsigned long nr_pages, struct mhp_params *params)
149{
150 return __add_pages(nid, start_pfn, nr_pages, params);
151}
152#else /* ARCH_HAS_ADD_PAGES */
153int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
154 struct mhp_params *params);
155#endif /* ARCH_HAS_ADD_PAGES */
156
157#ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
158/*
159 * For supporting node-hotadd, we have to allocate a new pgdat.
160 *
161 * If an arch has generic style NODE_DATA(),
162 * node_data[nid] = kzalloc() works well. But it depends on the architecture.
163 *
164 * In general, generic_alloc_nodedata() is used.
165 * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
166 *
167 */
168extern pg_data_t *arch_alloc_nodedata(int nid);
169extern void arch_free_nodedata(pg_data_t *pgdat);
170extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
171
172#else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
173
174#define arch_alloc_nodedata(nid) generic_alloc_nodedata(nid)
175#define arch_free_nodedata(pgdat) generic_free_nodedata(pgdat)
176
177#ifdef CONFIG_NUMA
178/*
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.
183 */
184#define generic_alloc_nodedata(nid) \
185({ \
186 kzalloc(sizeof(pg_data_t), GFP_KERNEL); \
187})
188/*
189 * This definition is just for error path in node hotadd.
190 * For node hotremove, we have to replace this.
191 */
192#define generic_free_nodedata(pgdat) kfree(pgdat)
193
194extern pg_data_t *node_data[];
195static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
196{
197 node_data[nid] = pgdat;
198}
199
200#else /* !CONFIG_NUMA */
201
202/* never called */
203static inline pg_data_t *generic_alloc_nodedata(int nid)
204{
205 BUG();
206 return NULL;
207}
208static inline void generic_free_nodedata(pg_data_t *pgdat)
209{
210}
211static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
212{
213}
214#endif /* CONFIG_NUMA */
215#endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
216
217void get_online_mems(void);
218void put_online_mems(void);
219
220void mem_hotplug_begin(void);
221void mem_hotplug_done(void);
222
223#else /* ! CONFIG_MEMORY_HOTPLUG */
224#define pfn_to_online_page(pfn) \
225({ \
226 struct page *___page = NULL; \
227 if (pfn_valid(pfn)) \
228 ___page = pfn_to_page(pfn); \
229 ___page; \
230 })
231
232static inline unsigned zone_span_seqbegin(struct zone *zone)
233{
234 return 0;
235}
236static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
237{
238 return 0;
239}
240static inline void zone_span_writelock(struct zone *zone) {}
241static inline void zone_span_writeunlock(struct zone *zone) {}
242static inline void zone_seqlock_init(struct zone *zone) {}
243
244static inline int try_online_node(int nid)
245{
246 return 0;
247}
248
249static inline void get_online_mems(void) {}
250static inline void put_online_mems(void) {}
251
252static inline void mem_hotplug_begin(void) {}
253static inline void mem_hotplug_done(void) {}
254
255static inline bool movable_node_is_enabled(void)
256{
257 return false;
258}
259#endif /* ! CONFIG_MEMORY_HOTPLUG */
260
261/*
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.
265 */
266struct range arch_get_mappable_range(void);
267
268#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
269/*
270 * pgdat resizing functions
271 */
272static inline
273void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
274{
275 spin_lock_irqsave(&pgdat->node_size_lock, *flags);
276}
277static inline
278void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
279{
280 spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
281}
282static inline
283void pgdat_resize_init(struct pglist_data *pgdat)
284{
285 spin_lock_init(&pgdat->node_size_lock);
286}
287#else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
288/*
289 * Stub functions for when hotplug is off
290 */
291static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
292static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
293static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
294#endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
295
296#ifdef CONFIG_MEMORY_HOTREMOVE
297
298extern void try_offline_node(int nid);
299extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages,
300 struct memory_group *group);
301extern int remove_memory(u64 start, u64 size);
302extern void __remove_memory(u64 start, u64 size);
303extern int offline_and_remove_memory(u64 start, u64 size);
304
305#else
306static inline void try_offline_node(int nid) {}
307
308static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages,
309 struct memory_group *group)
310{
311 return -EINVAL;
312}
313
314static inline int remove_memory(u64 start, u64 size)
315{
316 return -EBUSY;
317}
318
319static inline void __remove_memory(u64 start, u64 size) {}
320#endif /* CONFIG_MEMORY_HOTREMOVE */
321
322extern void set_zone_contiguous(struct zone *zone);
323extern void clear_zone_contiguous(struct zone *zone);
324
325#ifdef CONFIG_MEMORY_HOTPLUG
326extern void __ref free_area_init_core_hotplug(int nid);
327extern int __add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
328extern int add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags);
329extern int add_memory_resource(int nid, struct resource *resource,
330 mhp_t mhp_flags);
331extern int add_memory_driver_managed(int nid, u64 start, u64 size,
332 const char *resource_name,
333 mhp_t mhp_flags);
334extern 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);
337extern void remove_pfn_range_from_zone(struct zone *zone,
338 unsigned long start_pfn,
339 unsigned long nr_pages);
340extern bool is_memblock_offlined(struct memory_block *mem);
341extern int sparse_add_section(int nid, unsigned long pfn,
342 unsigned long nr_pages, struct vmem_altmap *altmap);
343extern 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);
346extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
347 unsigned long pnum);
348extern 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);
351extern int arch_create_linear_mapping(int nid, u64 start, u64 size,
352 struct mhp_params *params);
353void arch_remove_linear_mapping(u64 start, u64 size);
354extern bool mhp_supports_memmap_on_memory(unsigned long size);
355#endif /* CONFIG_MEMORY_HOTPLUG */
356
357#endif /* __LINUX_MEMORY_HOTPLUG_H */