LXR linux/include/linux/memory

   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
  19/*
  20 * Return page for the valid pfn only if the page is online. All pfn
  21 * walkers which rely on the fully initialized page->flags and others
  22 * should use this rather than pfn_valid && pfn_to_page
  23 */
  24#define pfn_to_online_page(pfn)                                    \
  25({                                                                 \
  26        struct page *___page = NULL;                               \
  27        unsigned long ___pfn = pfn;                                \
  28        unsigned long ___nr = pfn_to_section_nr(___pfn);           \
  29                                                                   \
  30        if (___nr < NR_MEM_SECTIONS && online_section_nr(___nr) && \
  31            pfn_valid_within(___pfn))                              \
  32                ___page = pfn_to_page(___pfn);                     \
  33        ___page;                                                   \
  34})
  35
  36/*
  37 * Types for free bootmem stored in page->lru.next. These have to be in
  38 * some random range in unsigned long space for debugging purposes.
  39 */
  40enum {
  41        MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE = 12,
  42        SECTION_INFO = MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE,
  43        MIX_SECTION_INFO,
  44        NODE_INFO,
  45        MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE = NODE_INFO,
  46};
  47
  48/* Types for control the zone type of onlined and offlined memory */
  49enum {
  50        MMOP_OFFLINE = -1,
  51        MMOP_ONLINE_KEEP,
  52        MMOP_ONLINE_KERNEL,
  53        MMOP_ONLINE_MOVABLE,
  54};
  55
  56/*
  57 * Restrictions for the memory hotplug:
  58 * flags:  MHP_ flags
  59 * altmap: alternative allocator for memmap array
  60 */
  61struct mhp_restrictions {
  62        unsigned long flags;
  63        struct vmem_altmap *altmap;
  64};
  65
  66/*
  67 * Zone resizing functions
  68 *
  69 * Note: any attempt to resize a zone should has pgdat_resize_lock()
  70 * zone_span_writelock() both held. This ensure the size of a zone
  71 * can't be changed while pgdat_resize_lock() held.
  72 */
  73static inline unsigned zone_span_seqbegin(struct zone *zone)
  74{
  75        return read_seqbegin(&zone->span_seqlock);
  76}
  77static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
  78{
  79        return read_seqretry(&zone->span_seqlock, iv);
  80}
  81static inline void zone_span_writelock(struct zone *zone)
  82{
  83        write_seqlock(&zone->span_seqlock);
  84}
  85static inline void zone_span_writeunlock(struct zone *zone)
  86{
  87        write_sequnlock(&zone->span_seqlock);
  88}
  89static inline void zone_seqlock_init(struct zone *zone)
  90{
  91        seqlock_init(&zone->span_seqlock);
  92}
  93extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages);
  94extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
  95extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
  96/* VM interface that may be used by firmware interface */
  97extern int online_pages(unsigned long, unsigned long, int);
  98extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
  99        unsigned long *valid_start, unsigned long *valid_end);
 100extern unsigned long __offline_isolated_pages(unsigned long start_pfn,
 101                                                unsigned long end_pfn);
 102
 103typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
 104
 105extern int set_online_page_callback(online_page_callback_t callback);
 106extern int restore_online_page_callback(online_page_callback_t callback);
 107
 108extern void __online_page_set_limits(struct page *page);
 109extern void __online_page_increment_counters(struct page *page);
 110extern void __online_page_free(struct page *page);
 111
 112extern int try_online_node(int nid);
 113
 114extern int arch_add_memory(int nid, u64 start, u64 size,
 115                        struct mhp_restrictions *restrictions);
 116extern u64 max_mem_size;
 117
 118extern bool memhp_auto_online;
 119/* If movable_node boot option specified */
 120extern bool movable_node_enabled;
 121static inline bool movable_node_is_enabled(void)
 122{
 123        return movable_node_enabled;
 124}
 125
 126extern void arch_remove_memory(int nid, u64 start, u64 size,
 127                               struct vmem_altmap *altmap);
 128extern void __remove_pages(struct zone *zone, unsigned long start_pfn,
 129                           unsigned long nr_pages, struct vmem_altmap *altmap);
 130
 131/* reasonably generic interface to expand the physical pages */
 132extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
 133                       struct mhp_restrictions *restrictions);
 134
 135#ifndef CONFIG_ARCH_HAS_ADD_PAGES
 136static inline int add_pages(int nid, unsigned long start_pfn,
 137                unsigned long nr_pages, struct mhp_restrictions *restrictions)
 138{
 139        return __add_pages(nid, start_pfn, nr_pages, restrictions);
 140}
 141#else /* ARCH_HAS_ADD_PAGES */
 142int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
 143              struct mhp_restrictions *restrictions);
 144#endif /* ARCH_HAS_ADD_PAGES */
 145
 146#ifdef CONFIG_NUMA
 147extern int memory_add_physaddr_to_nid(u64 start);
 148#else
 149static inline int memory_add_physaddr_to_nid(u64 start)
 150{
 151        return 0;
 152}
 153#endif
 154
 155#ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
 156/*
 157 * For supporting node-hotadd, we have to allocate a new pgdat.
 158 *
 159 * If an arch has generic style NODE_DATA(),
 160 * node_data[nid] = kzalloc() works well. But it depends on the architecture.
 161 *
 162 * In general, generic_alloc_nodedata() is used.
 163 * Now, arch_free_nodedata() is just defined for error path of node_hot_add.
 164 *
 165 */
 166extern pg_data_t *arch_alloc_nodedata(int nid);
 167extern void arch_free_nodedata(pg_data_t *pgdat);
 168extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
 169
 170#else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
 171
 172#define arch_alloc_nodedata(nid)        generic_alloc_nodedata(nid)
 173#define arch_free_nodedata(pgdat)       generic_free_nodedata(pgdat)
 174
 175#ifdef CONFIG_NUMA
 176/*
 177 * If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
 178 * XXX: kmalloc_node() can't work well to get new node's memory at this time.
 179 *      Because, pgdat for the new node is not allocated/initialized yet itself.
 180 *      To use new node's memory, more consideration will be necessary.
 181 */
 182#define generic_alloc_nodedata(nid)                             \
 183({                                                              \
 184        kzalloc(sizeof(pg_data_t), GFP_KERNEL);                 \
 185})
 186/*
 187 * This definition is just for error path in node hotadd.
 188 * For node hotremove, we have to replace this.
 189 */
 190#define generic_free_nodedata(pgdat)    kfree(pgdat)
 191
 192extern pg_data_t *node_data[];
 193static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
 194{
 195        node_data[nid] = pgdat;
 196}
 197
 198#else /* !CONFIG_NUMA */
 199
 200/* never called */
 201static inline pg_data_t *generic_alloc_nodedata(int nid)
 202{
 203        BUG();
 204        return NULL;
 205}
 206static inline void generic_free_nodedata(pg_data_t *pgdat)
 207{
 208}
 209static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
 210{
 211}
 212#endif /* CONFIG_NUMA */
 213#endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
 214
 215#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
 216extern void __init register_page_bootmem_info_node(struct pglist_data *pgdat);
 217#else
 218static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
 219{
 220}
 221#endif
 222extern void put_page_bootmem(struct page *page);
 223extern void get_page_bootmem(unsigned long ingo, struct page *page,
 224                             unsigned long type);
 225
 226void get_online_mems(void);
 227void put_online_mems(void);
 228
 229void mem_hotplug_begin(void);
 230void mem_hotplug_done(void);
 231
 232extern void set_zone_contiguous(struct zone *zone);
 233extern void clear_zone_contiguous(struct zone *zone);
 234
 235#else /* ! CONFIG_MEMORY_HOTPLUG */
 236#define pfn_to_online_page(pfn)                 \
 237({                                              \
 238        struct page *___page = NULL;            \
 239        if (pfn_valid(pfn))                     \
 240                ___page = pfn_to_page(pfn);     \
 241        ___page;                                \
 242 })
 243
 244static inline unsigned zone_span_seqbegin(struct zone *zone)
 245{
 246        return 0;
 247}
 248static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
 249{
 250        return 0;
 251}
 252static inline void zone_span_writelock(struct zone *zone) {}
 253static inline void zone_span_writeunlock(struct zone *zone) {}
 254static inline void zone_seqlock_init(struct zone *zone) {}
 255
 256static inline int mhp_notimplemented(const char *func)
 257{
 258        printk(KERN_WARNING "%s() called, with CONFIG_MEMORY_HOTPLUG disabled\n", func);
 259        dump_stack();
 260        return -ENOSYS;
 261}
 262
 263static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
 264{
 265}
 266
 267static inline int try_online_node(int nid)
 268{
 269        return 0;
 270}
 271
 272static inline void get_online_mems(void) {}
 273static inline void put_online_mems(void) {}
 274
 275static inline void mem_hotplug_begin(void) {}
 276static inline void mem_hotplug_done(void) {}
 277
 278static inline bool movable_node_is_enabled(void)
 279{
 280        return false;
 281}
 282#endif /* ! CONFIG_MEMORY_HOTPLUG */
 283
 284#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
 285/*
 286 * pgdat resizing functions
 287 */
 288static inline
 289void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
 290{
 291        spin_lock_irqsave(&pgdat->node_size_lock, *flags);
 292}
 293static inline
 294void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
 295{
 296        spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
 297}
 298static inline
 299void pgdat_resize_init(struct pglist_data *pgdat)
 300{
 301        spin_lock_init(&pgdat->node_size_lock);
 302}
 303#else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
 304/*
 305 * Stub functions for when hotplug is off
 306 */
 307static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
 308static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
 309static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
 310#endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
 311
 312#ifdef CONFIG_MEMORY_HOTREMOVE
 313
 314extern bool is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
 315extern void try_offline_node(int nid);
 316extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
 317extern int remove_memory(int nid, u64 start, u64 size);
 318extern void __remove_memory(int nid, u64 start, u64 size);
 319
 320#else
 321static inline bool is_mem_section_removable(unsigned long pfn,
 322                                        unsigned long nr_pages)
 323{
 324        return false;
 325}
 326
 327static inline void try_offline_node(int nid) {}
 328
 329static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
 330{
 331        return -EINVAL;
 332}
 333
 334static inline int remove_memory(int nid, u64 start, u64 size)
 335{
 336        return -EBUSY;
 337}
 338
 339static inline void __remove_memory(int nid, u64 start, u64 size) {}
 340#endif /* CONFIG_MEMORY_HOTREMOVE */
 341
 342extern void __ref free_area_init_core_hotplug(int nid);
 343extern int __add_memory(int nid, u64 start, u64 size);
 344extern int add_memory(int nid, u64 start, u64 size);
 345extern int add_memory_resource(int nid, struct resource *resource);
 346extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
 347                unsigned long nr_pages, struct vmem_altmap *altmap);
 348extern bool is_memblock_offlined(struct memory_block *mem);
 349extern int sparse_add_section(int nid, unsigned long pfn,
 350                unsigned long nr_pages, struct vmem_altmap *altmap);
 351extern void sparse_remove_section(struct mem_section *ms,
 352                unsigned long pfn, unsigned long nr_pages,
 353                unsigned long map_offset, struct vmem_altmap *altmap);
 354extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
 355                                          unsigned long pnum);
 356extern bool allow_online_pfn_range(int nid, unsigned long pfn, unsigned long nr_pages,
 357                int online_type);
 358extern struct zone *zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
 359                unsigned long nr_pages);
 360#endif /* __LINUX_MEMORY_HOTPLUG_H */
 361