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 10 struct page; 11 struct zone; 12 struct pglist_data; 13 struct mem_section; 14 struct memory_group; 15 struct resource; 16 struct vmem_altmap; 17 struct dev_pagemap; 18 19 #ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION 20 /* 21 * For supporting node-hotadd, we have to allocate a new pgdat. 22 * 23 * If an arch has generic style NODE_DATA(), 24 * node_data[nid] = kzalloc() works well. But it depends on the architecture. 25 * 26 * In general, generic_alloc_nodedata() is used. 27 * 28 */ 29 extern pg_data_t *arch_alloc_nodedata(int nid); 30 extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat); 31 32 #else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */ 33 34 #define arch_alloc_nodedata(nid) generic_alloc_nodedata(nid) 35 36 #ifdef CONFIG_NUMA 37 /* 38 * XXX: node aware allocation can't work well to get new node's memory at this time. 39 * Because, pgdat for the new node is not allocated/initialized yet itself. 40 * To use new node's memory, more consideration will be necessary. 41 */ 42 #define generic_alloc_nodedata(nid) \ 43 ({ \ 44 memblock_alloc(sizeof(*pgdat), SMP_CACHE_BYTES); \ 45 }) 46 47 extern pg_data_t *node_data[]; 48 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat) 49 { 50 node_data[nid] = pgdat; 51 } 52 53 #else /* !CONFIG_NUMA */ 54 55 /* never called */ 56 static inline pg_data_t *generic_alloc_nodedata(int nid) 57 { 58 BUG(); 59 return NULL; 60 } 61 static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat) 62 { 63 } 64 #endif /* CONFIG_NUMA */ 65 #endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */ 66 67 #ifdef CONFIG_MEMORY_HOTPLUG 68 struct page *pfn_to_online_page(unsigned long pfn); 69 70 /* Types for control the zone type of onlined and offlined memory */ 71 enum { 72 /* Offline the memory. */ 73 MMOP_OFFLINE = 0, 74 /* Online the memory. Zone depends, see default_zone_for_pfn(). */ 75 MMOP_ONLINE, 76 /* Online the memory to ZONE_NORMAL. */ 77 MMOP_ONLINE_KERNEL, 78 /* Online the memory to ZONE_MOVABLE. */ 79 MMOP_ONLINE_MOVABLE, 80 }; 81 82 /* Flags for add_memory() and friends to specify memory hotplug details. */ 83 typedef int __bitwise mhp_t; 84 85 /* No special request */ 86 #define MHP_NONE ((__force mhp_t)0) 87 /* 88 * Allow merging of the added System RAM resource with adjacent, 89 * mergeable resources. After a successful call to add_memory_resource() 90 * with this flag set, the resource pointer must no longer be used as it 91 * might be stale, or the resource might have changed. 92 */ 93 #define MHP_MERGE_RESOURCE ((__force mhp_t)BIT(0)) 94 95 /* 96 * We want memmap (struct page array) to be self contained. 97 * To do so, we will use the beginning of the hot-added range to build 98 * the page tables for the memmap array that describes the entire range. 99 * Only selected architectures support it with SPARSE_VMEMMAP. 100 * This is only a hint, the core kernel can decide to not do this based on 101 * different alignment checks. 102 */ 103 #define MHP_MEMMAP_ON_MEMORY ((__force mhp_t)BIT(1)) 104 /* 105 * The nid field specifies a memory group id (mgid) instead. The memory group 106 * implies the node id (nid). 107 */ 108 #define MHP_NID_IS_MGID ((__force mhp_t)BIT(2)) 109 /* 110 * The hotplugged memory is completely inaccessible while the memory is 111 * offline. The memory provider will handle MEM_PREPARE_ONLINE / 112 * MEM_FINISH_OFFLINE notifications and make the memory accessible. 113 * 114 * This flag is only relevant when used along with MHP_MEMMAP_ON_MEMORY, 115 * because the altmap cannot be written (e.g., poisoned) when adding 116 * memory -- before it is set online. 117 * 118 * This allows for adding memory with an altmap that is not currently 119 * made available by a hypervisor. When onlining that memory, the 120 * hypervisor can be instructed to make that memory available, and 121 * the onlining phase will not require any memory allocations, which is 122 * helpful in low-memory situations. 123 */ 124 #define MHP_OFFLINE_INACCESSIBLE ((__force mhp_t)BIT(3)) 125 126 /* 127 * Extended parameters for memory hotplug: 128 * altmap: alternative allocator for memmap array (optional) 129 * pgprot: page protection flags to apply to newly created page tables 130 * (required) 131 */ 132 struct mhp_params { 133 struct vmem_altmap *altmap; 134 pgprot_t pgprot; 135 struct dev_pagemap *pgmap; 136 }; 137 138 bool mhp_range_allowed(u64 start, u64 size, bool need_mapping); 139 struct range mhp_get_pluggable_range(bool need_mapping); 140 bool mhp_supports_memmap_on_memory(void); 141 142 /* 143 * Zone resizing functions 144 * 145 * Note: any attempt to resize a zone should has pgdat_resize_lock() 146 * zone_span_writelock() both held. This ensure the size of a zone 147 * can't be changed while pgdat_resize_lock() held. 148 */ 149 static inline unsigned zone_span_seqbegin(struct zone *zone) 150 { 151 return read_seqbegin(&zone->span_seqlock); 152 } 153 static inline int zone_span_seqretry(struct zone *zone, unsigned iv) 154 { 155 return read_seqretry(&zone->span_seqlock, iv); 156 } 157 static inline void zone_span_writelock(struct zone *zone) 158 { 159 write_seqlock(&zone->span_seqlock); 160 } 161 static inline void zone_span_writeunlock(struct zone *zone) 162 { 163 write_sequnlock(&zone->span_seqlock); 164 } 165 static inline void zone_seqlock_init(struct zone *zone) 166 { 167 seqlock_init(&zone->span_seqlock); 168 } 169 extern void adjust_present_page_count(struct page *page, 170 struct memory_group *group, 171 long nr_pages); 172 /* VM interface that may be used by firmware interface */ 173 extern int mhp_init_memmap_on_memory(unsigned long pfn, unsigned long nr_pages, 174 struct zone *zone, bool mhp_off_inaccessible); 175 extern void mhp_deinit_memmap_on_memory(unsigned long pfn, unsigned long nr_pages); 176 extern int online_pages(unsigned long pfn, unsigned long nr_pages, 177 struct zone *zone, struct memory_group *group); 178 extern void __offline_isolated_pages(unsigned long start_pfn, 179 unsigned long end_pfn); 180 181 typedef void (*online_page_callback_t)(struct page *page, unsigned int order); 182 183 extern void generic_online_page(struct page *page, unsigned int order); 184 extern int set_online_page_callback(online_page_callback_t callback); 185 extern int restore_online_page_callback(online_page_callback_t callback); 186 187 extern int try_online_node(int nid); 188 189 extern int arch_add_memory(int nid, u64 start, u64 size, 190 struct mhp_params *params); 191 extern u64 max_mem_size; 192 193 extern int mhp_online_type_from_str(const char *str); 194 195 /* Default online_type (MMOP_*) when new memory blocks are added. */ 196 extern int mhp_default_online_type; 197 /* If movable_node boot option specified */ 198 extern bool movable_node_enabled; 199 static inline bool movable_node_is_enabled(void) 200 { 201 return movable_node_enabled; 202 } 203 204 extern void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap); 205 extern void __remove_pages(unsigned long start_pfn, unsigned long nr_pages, 206 struct vmem_altmap *altmap); 207 208 /* reasonably generic interface to expand the physical pages */ 209 extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 210 struct mhp_params *params); 211 212 #ifndef CONFIG_ARCH_HAS_ADD_PAGES 213 static inline int add_pages(int nid, unsigned long start_pfn, 214 unsigned long nr_pages, struct mhp_params *params) 215 { 216 return __add_pages(nid, start_pfn, nr_pages, params); 217 } 218 #else /* ARCH_HAS_ADD_PAGES */ 219 int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages, 220 struct mhp_params *params); 221 #endif /* ARCH_HAS_ADD_PAGES */ 222 223 void get_online_mems(void); 224 void put_online_mems(void); 225 226 void mem_hotplug_begin(void); 227 void mem_hotplug_done(void); 228 229 /* See kswapd_is_running() */ 230 static inline void pgdat_kswapd_lock(pg_data_t *pgdat) 231 { 232 mutex_lock(&pgdat->kswapd_lock); 233 } 234 235 static inline void pgdat_kswapd_unlock(pg_data_t *pgdat) 236 { 237 mutex_unlock(&pgdat->kswapd_lock); 238 } 239 240 static inline void pgdat_kswapd_lock_init(pg_data_t *pgdat) 241 { 242 mutex_init(&pgdat->kswapd_lock); 243 } 244 245 #else /* ! CONFIG_MEMORY_HOTPLUG */ 246 #define pfn_to_online_page(pfn) \ 247 ({ \ 248 struct page *___page = NULL; \ 249 if (pfn_valid(pfn)) \ 250 ___page = pfn_to_page(pfn); \ 251 ___page; \ 252 }) 253 254 static inline unsigned zone_span_seqbegin(struct zone *zone) 255 { 256 return 0; 257 } 258 static inline int zone_span_seqretry(struct zone *zone, unsigned iv) 259 { 260 return 0; 261 } 262 static inline void zone_span_writelock(struct zone *zone) {} 263 static inline void zone_span_writeunlock(struct zone *zone) {} 264 static inline void zone_seqlock_init(struct zone *zone) {} 265 266 static inline int try_online_node(int nid) 267 { 268 return 0; 269 } 270 271 static inline void get_online_mems(void) {} 272 static inline void put_online_mems(void) {} 273 274 static inline void mem_hotplug_begin(void) {} 275 static inline void mem_hotplug_done(void) {} 276 277 static inline bool movable_node_is_enabled(void) 278 { 279 return false; 280 } 281 282 static inline bool mhp_supports_memmap_on_memory(void) 283 { 284 return false; 285 } 286 287 static inline void pgdat_kswapd_lock(pg_data_t *pgdat) {} 288 static inline void pgdat_kswapd_unlock(pg_data_t *pgdat) {} 289 static inline void pgdat_kswapd_lock_init(pg_data_t *pgdat) {} 290 #endif /* ! CONFIG_MEMORY_HOTPLUG */ 291 292 /* 293 * Keep this declaration outside CONFIG_MEMORY_HOTPLUG as some 294 * platforms might override and use arch_get_mappable_range() 295 * for internal non memory hotplug purposes. 296 */ 297 struct range arch_get_mappable_range(void); 298 299 #if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT) 300 /* 301 * pgdat resizing functions 302 */ 303 static inline 304 void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags) 305 { 306 spin_lock_irqsave(&pgdat->node_size_lock, *flags); 307 } 308 static inline 309 void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags) 310 { 311 spin_unlock_irqrestore(&pgdat->node_size_lock, *flags); 312 } 313 static inline 314 void pgdat_resize_init(struct pglist_data *pgdat) 315 { 316 spin_lock_init(&pgdat->node_size_lock); 317 } 318 #else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */ 319 /* 320 * Stub functions for when hotplug is off 321 */ 322 static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {} 323 static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {} 324 static inline void pgdat_resize_init(struct pglist_data *pgdat) {} 325 #endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */ 326 327 #ifdef CONFIG_MEMORY_HOTREMOVE 328 329 extern void try_offline_node(int nid); 330 extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages, 331 struct zone *zone, struct memory_group *group); 332 extern int remove_memory(u64 start, u64 size); 333 extern void __remove_memory(u64 start, u64 size); 334 extern int offline_and_remove_memory(u64 start, u64 size); 335 336 #else 337 static inline void try_offline_node(int nid) {} 338 339 static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages, 340 struct zone *zone, struct memory_group *group) 341 { 342 return -EINVAL; 343 } 344 345 static inline int remove_memory(u64 start, u64 size) 346 { 347 return -EBUSY; 348 } 349 350 static inline void __remove_memory(u64 start, u64 size) {} 351 #endif /* CONFIG_MEMORY_HOTREMOVE */ 352 353 #ifdef CONFIG_MEMORY_HOTPLUG 354 extern void __ref free_area_init_core_hotplug(struct pglist_data *pgdat); 355 extern int __add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags); 356 extern int add_memory(int nid, u64 start, u64 size, mhp_t mhp_flags); 357 extern int add_memory_resource(int nid, struct resource *resource, 358 mhp_t mhp_flags); 359 extern int add_memory_driver_managed(int nid, u64 start, u64 size, 360 const char *resource_name, 361 mhp_t mhp_flags); 362 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn, 363 unsigned long nr_pages, 364 struct vmem_altmap *altmap, int migratetype); 365 extern void remove_pfn_range_from_zone(struct zone *zone, 366 unsigned long start_pfn, 367 unsigned long nr_pages); 368 extern int sparse_add_section(int nid, unsigned long pfn, 369 unsigned long nr_pages, struct vmem_altmap *altmap, 370 struct dev_pagemap *pgmap); 371 extern void sparse_remove_section(unsigned long pfn, unsigned long nr_pages, 372 struct vmem_altmap *altmap); 373 extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map, 374 unsigned long pnum); 375 extern struct zone *zone_for_pfn_range(int online_type, int nid, 376 struct memory_group *group, unsigned long start_pfn, 377 unsigned long nr_pages); 378 extern int arch_create_linear_mapping(int nid, u64 start, u64 size, 379 struct mhp_params *params); 380 void arch_remove_linear_mapping(u64 start, u64 size); 381 #endif /* CONFIG_MEMORY_HOTPLUG */ 382 383 #endif /* __LINUX_MEMORY_HOTPLUG_H */ 384