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 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 */
 358