1 #ifndef _LINUX_MMZONE_H 2 #define _LINUX_MMZONE_H 3 4 #ifndef __ASSEMBLY__ 5 #ifndef __GENERATING_BOUNDS_H 6 7 #include <linux/spinlock.h> 8 #include <linux/list.h> 9 #include <linux/wait.h> 10 #include <linux/bitops.h> 11 #include <linux/cache.h> 12 #include <linux/threads.h> 13 #include <linux/numa.h> 14 #include <linux/init.h> 15 #include <linux/seqlock.h> 16 #include <linux/nodemask.h> 17 #include <linux/pageblock-flags.h> 18 #include <linux/page-flags-layout.h> 19 #include <linux/atomic.h> 20 #include <asm/page.h> 21 22 /* Free memory management - zoned buddy allocator. */ 23 #ifndef CONFIG_FORCE_MAX_ZONEORDER 24 #define MAX_ORDER 11 25 #else 26 #define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER 27 #endif 28 #define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1)) 29 30 /* 31 * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed 32 * costly to service. That is between allocation orders which should 33 * coalesce naturally under reasonable reclaim pressure and those which 34 * will not. 35 */ 36 #define PAGE_ALLOC_COSTLY_ORDER 3 37 38 enum migratetype { 39 MIGRATE_UNMOVABLE, 40 MIGRATE_MOVABLE, 41 MIGRATE_RECLAIMABLE, 42 MIGRATE_PCPTYPES, /* the number of types on the pcp lists */ 43 MIGRATE_HIGHATOMIC = MIGRATE_PCPTYPES, 44 #ifdef CONFIG_CMA 45 /* 46 * MIGRATE_CMA migration type is designed to mimic the way 47 * ZONE_MOVABLE works. Only movable pages can be allocated 48 * from MIGRATE_CMA pageblocks and page allocator never 49 * implicitly change migration type of MIGRATE_CMA pageblock. 50 * 51 * The way to use it is to change migratetype of a range of 52 * pageblocks to MIGRATE_CMA which can be done by 53 * __free_pageblock_cma() function. What is important though 54 * is that a range of pageblocks must be aligned to 55 * MAX_ORDER_NR_PAGES should biggest page be bigger then 56 * a single pageblock. 57 */ 58 MIGRATE_CMA, 59 #endif 60 #ifdef CONFIG_MEMORY_ISOLATION 61 MIGRATE_ISOLATE, /* can't allocate from here */ 62 #endif 63 MIGRATE_TYPES 64 }; 65 66 /* In mm/page_alloc.c; keep in sync also with show_migration_types() there */ 67 extern char * const migratetype_names[MIGRATE_TYPES]; 68 69 #ifdef CONFIG_CMA 70 # define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA) 71 # define is_migrate_cma_page(_page) (get_pageblock_migratetype(_page) == MIGRATE_CMA) 72 #else 73 # define is_migrate_cma(migratetype) false 74 # define is_migrate_cma_page(_page) false 75 #endif 76 77 static inline bool is_migrate_movable(int mt) 78 { 79 return is_migrate_cma(mt) || mt == MIGRATE_MOVABLE; 80 } 81 82 #define for_each_migratetype_order(order, type) \ 83 for (order = 0; order < MAX_ORDER; order++) \ 84 for (type = 0; type < MIGRATE_TYPES; type++) 85 86 extern int page_group_by_mobility_disabled; 87 88 #define NR_MIGRATETYPE_BITS (PB_migrate_end - PB_migrate + 1) 89 #define MIGRATETYPE_MASK ((1UL << NR_MIGRATETYPE_BITS) - 1) 90 91 #define get_pageblock_migratetype(page) \ 92 get_pfnblock_flags_mask(page, page_to_pfn(page), \ 93 PB_migrate_end, MIGRATETYPE_MASK) 94 95 struct free_area { 96 struct list_head free_list[MIGRATE_TYPES]; 97 unsigned long nr_free; 98 }; 99 100 struct pglist_data; 101 102 /* 103 * zone->lock and the zone lru_lock are two of the hottest locks in the kernel. 104 * So add a wild amount of padding here to ensure that they fall into separate 105 * cachelines. There are very few zone structures in the machine, so space 106 * consumption is not a concern here. 107 */ 108 #if defined(CONFIG_SMP) 109 struct zone_padding { 110 char x[0]; 111 } ____cacheline_internodealigned_in_smp; 112 #define ZONE_PADDING(name) struct zone_padding name; 113 #else 114 #define ZONE_PADDING(name) 115 #endif 116 117 #ifdef CONFIG_NUMA 118 enum numa_stat_item { 119 NUMA_HIT, /* allocated in intended node */ 120 NUMA_MISS, /* allocated in non intended node */ 121 NUMA_FOREIGN, /* was intended here, hit elsewhere */ 122 NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */ 123 NUMA_LOCAL, /* allocation from local node */ 124 NUMA_OTHER, /* allocation from other node */ 125 NR_VM_NUMA_STAT_ITEMS 126 }; 127 #else 128 #define NR_VM_NUMA_STAT_ITEMS 0 129 #endif 130 131 enum zone_stat_item { 132 /* First 128 byte cacheline (assuming 64 bit words) */ 133 NR_FREE_PAGES, 134 NR_ZONE_LRU_BASE, /* Used only for compaction and reclaim retry */ 135 NR_ZONE_INACTIVE_ANON = NR_ZONE_LRU_BASE, 136 NR_ZONE_ACTIVE_ANON, 137 NR_ZONE_INACTIVE_FILE, 138 NR_ZONE_ACTIVE_FILE, 139 NR_ZONE_UNEVICTABLE, 140 NR_ZONE_WRITE_PENDING, /* Count of dirty, writeback and unstable pages */ 141 NR_MLOCK, /* mlock()ed pages found and moved off LRU */ 142 NR_PAGETABLE, /* used for pagetables */ 143 NR_KERNEL_STACK_KB, /* measured in KiB */ 144 /* Second 128 byte cacheline */ 145 NR_BOUNCE, 146 #if IS_ENABLED(CONFIG_ZSMALLOC) 147 NR_ZSPAGES, /* allocated in zsmalloc */ 148 #endif 149 NR_FREE_CMA_PAGES, 150 NR_VM_ZONE_STAT_ITEMS }; 151 152 enum node_stat_item { 153 NR_LRU_BASE, 154 NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */ 155 NR_ACTIVE_ANON, /* " " " " " */ 156 NR_INACTIVE_FILE, /* " " " " " */ 157 NR_ACTIVE_FILE, /* " " " " " */ 158 NR_UNEVICTABLE, /* " " " " " */ 159 NR_SLAB_RECLAIMABLE, 160 NR_SLAB_UNRECLAIMABLE, 161 NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */ 162 NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */ 163 WORKINGSET_REFAULT, 164 WORKINGSET_ACTIVATE, 165 WORKINGSET_NODERECLAIM, 166 NR_ANON_MAPPED, /* Mapped anonymous pages */ 167 NR_FILE_MAPPED, /* pagecache pages mapped into pagetables. 168 only modified from process context */ 169 NR_FILE_PAGES, 170 NR_FILE_DIRTY, 171 NR_WRITEBACK, 172 NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */ 173 NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */ 174 NR_SHMEM_THPS, 175 NR_SHMEM_PMDMAPPED, 176 NR_ANON_THPS, 177 NR_UNSTABLE_NFS, /* NFS unstable pages */ 178 NR_VMSCAN_WRITE, 179 NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */ 180 NR_DIRTIED, /* page dirtyings since bootup */ 181 NR_WRITTEN, /* page writings since bootup */ 182 NR_VM_NODE_STAT_ITEMS 183 }; 184 185 /* 186 * We do arithmetic on the LRU lists in various places in the code, 187 * so it is important to keep the active lists LRU_ACTIVE higher in 188 * the array than the corresponding inactive lists, and to keep 189 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists. 190 * 191 * This has to be kept in sync with the statistics in zone_stat_item 192 * above and the descriptions in vmstat_text in mm/vmstat.c 193 */ 194 #define LRU_BASE 0 195 #define LRU_ACTIVE 1 196 #define LRU_FILE 2 197 198 enum lru_list { 199 LRU_INACTIVE_ANON = LRU_BASE, 200 LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE, 201 LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE, 202 LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE, 203 LRU_UNEVICTABLE, 204 NR_LRU_LISTS 205 }; 206 207 #define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++) 208 209 #define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++) 210 211 static inline int is_file_lru(enum lru_list lru) 212 { 213 return (lru == LRU_INACTIVE_FILE || lru == LRU_ACTIVE_FILE); 214 } 215 216 static inline int is_active_lru(enum lru_list lru) 217 { 218 return (lru == LRU_ACTIVE_ANON || lru == LRU_ACTIVE_FILE); 219 } 220 221 struct zone_reclaim_stat { 222 /* 223 * The pageout code in vmscan.c keeps track of how many of the 224 * mem/swap backed and file backed pages are referenced. 225 * The higher the rotated/scanned ratio, the more valuable 226 * that cache is. 227 * 228 * The anon LRU stats live in [0], file LRU stats in [1] 229 */ 230 unsigned long recent_rotated[2]; 231 unsigned long recent_scanned[2]; 232 }; 233 234 struct lruvec { 235 struct list_head lists[NR_LRU_LISTS]; 236 struct zone_reclaim_stat reclaim_stat; 237 /* Evictions & activations on the inactive file list */ 238 atomic_long_t inactive_age; 239 /* Refaults at the time of last reclaim cycle */ 240 unsigned long refaults; 241 #ifdef CONFIG_MEMCG 242 struct pglist_data *pgdat; 243 #endif 244 }; 245 246 /* Mask used at gathering information at once (see memcontrol.c) */ 247 #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE)) 248 #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON)) 249 #define LRU_ALL ((1 << NR_LRU_LISTS) - 1) 250 251 /* Isolate unmapped file */ 252 #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2) 253 /* Isolate for asynchronous migration */ 254 #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4) 255 /* Isolate unevictable pages */ 256 #define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8) 257 258 /* LRU Isolation modes. */ 259 typedef unsigned __bitwise isolate_mode_t; 260 261 enum zone_watermarks { 262 WMARK_MIN, 263 WMARK_LOW, 264 WMARK_HIGH, 265 NR_WMARK 266 }; 267 268 #define min_wmark_pages(z) (z->watermark[WMARK_MIN]) 269 #define low_wmark_pages(z) (z->watermark[WMARK_LOW]) 270 #define high_wmark_pages(z) (z->watermark[WMARK_HIGH]) 271 272 struct per_cpu_pages { 273 int count; /* number of pages in the list */ 274 int high; /* high watermark, emptying needed */ 275 int batch; /* chunk size for buddy add/remove */ 276 277 /* Lists of pages, one per migrate type stored on the pcp-lists */ 278 struct list_head lists[MIGRATE_PCPTYPES]; 279 }; 280 281 struct per_cpu_pageset { 282 struct per_cpu_pages pcp; 283 #ifdef CONFIG_NUMA 284 s8 expire; 285 u16 vm_numa_stat_diff[NR_VM_NUMA_STAT_ITEMS]; 286 #endif 287 #ifdef CONFIG_SMP 288 s8 stat_threshold; 289 s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS]; 290 #endif 291 }; 292 293 struct per_cpu_nodestat { 294 s8 stat_threshold; 295 s8 vm_node_stat_diff[NR_VM_NODE_STAT_ITEMS]; 296 }; 297 298 #endif /* !__GENERATING_BOUNDS.H */ 299 300 enum zone_type { 301 #ifdef CONFIG_ZONE_DMA 302 /* 303 * ZONE_DMA is used when there are devices that are not able 304 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we 305 * carve out the portion of memory that is needed for these devices. 306 * The range is arch specific. 307 * 308 * Some examples 309 * 310 * Architecture Limit 311 * --------------------------- 312 * parisc, ia64, sparc <4G 313 * s390 <2G 314 * arm Various 315 * alpha Unlimited or 0-16MB. 316 * 317 * i386, x86_64 and multiple other arches 318 * <16M. 319 */ 320 ZONE_DMA, 321 #endif 322 #ifdef CONFIG_ZONE_DMA32 323 /* 324 * x86_64 needs two ZONE_DMAs because it supports devices that are 325 * only able to do DMA to the lower 16M but also 32 bit devices that 326 * can only do DMA areas below 4G. 327 */ 328 ZONE_DMA32, 329 #endif 330 /* 331 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be 332 * performed on pages in ZONE_NORMAL if the DMA devices support 333 * transfers to all addressable memory. 334 */ 335 ZONE_NORMAL, 336 #ifdef CONFIG_HIGHMEM 337 /* 338 * A memory area that is only addressable by the kernel through 339 * mapping portions into its own address space. This is for example 340 * used by i386 to allow the kernel to address the memory beyond 341 * 900MB. The kernel will set up special mappings (page 342 * table entries on i386) for each page that the kernel needs to 343 * access. 344 */ 345 ZONE_HIGHMEM, 346 #endif 347 ZONE_MOVABLE, 348 #ifdef CONFIG_ZONE_DEVICE 349 ZONE_DEVICE, 350 #endif 351 __MAX_NR_ZONES 352 353 }; 354 355 #ifndef __GENERATING_BOUNDS_H 356 357 struct zone { 358 /* Read-mostly fields */ 359 360 /* zone watermarks, access with *_wmark_pages(zone) macros */ 361 unsigned long watermark[NR_WMARK]; 362 363 unsigned long nr_reserved_highatomic; 364 365 /* 366 * We don't know if the memory that we're going to allocate will be 367 * freeable or/and it will be released eventually, so to avoid totally 368 * wasting several GB of ram we must reserve some of the lower zone 369 * memory (otherwise we risk to run OOM on the lower zones despite 370 * there being tons of freeable ram on the higher zones). This array is 371 * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl 372 * changes. 373 */ 374 long lowmem_reserve[MAX_NR_ZONES]; 375 376 #ifdef CONFIG_NUMA 377 int node; 378 #endif 379 struct pglist_data *zone_pgdat; 380 struct per_cpu_pageset __percpu *pageset; 381 382 #ifndef CONFIG_SPARSEMEM 383 /* 384 * Flags for a pageblock_nr_pages block. See pageblock-flags.h. 385 * In SPARSEMEM, this map is stored in struct mem_section 386 */ 387 unsigned long *pageblock_flags; 388 #endif /* CONFIG_SPARSEMEM */ 389 390 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */ 391 unsigned long zone_start_pfn; 392 393 /* 394 * spanned_pages is the total pages spanned by the zone, including 395 * holes, which is calculated as: 396 * spanned_pages = zone_end_pfn - zone_start_pfn; 397 * 398 * present_pages is physical pages existing within the zone, which 399 * is calculated as: 400 * present_pages = spanned_pages - absent_pages(pages in holes); 401 * 402 * managed_pages is present pages managed by the buddy system, which 403 * is calculated as (reserved_pages includes pages allocated by the 404 * bootmem allocator): 405 * managed_pages = present_pages - reserved_pages; 406 * 407 * So present_pages may be used by memory hotplug or memory power 408 * management logic to figure out unmanaged pages by checking 409 * (present_pages - managed_pages). And managed_pages should be used 410 * by page allocator and vm scanner to calculate all kinds of watermarks 411 * and thresholds. 412 * 413 * Locking rules: 414 * 415 * zone_start_pfn and spanned_pages are protected by span_seqlock. 416 * It is a seqlock because it has to be read outside of zone->lock, 417 * and it is done in the main allocator path. But, it is written 418 * quite infrequently. 419 * 420 * The span_seq lock is declared along with zone->lock because it is 421 * frequently read in proximity to zone->lock. It's good to 422 * give them a chance of being in the same cacheline. 423 * 424 * Write access to present_pages at runtime should be protected by 425 * mem_hotplug_begin/end(). Any reader who can't tolerant drift of 426 * present_pages should get_online_mems() to get a stable value. 427 * 428 * Read access to managed_pages should be safe because it's unsigned 429 * long. Write access to zone->managed_pages and totalram_pages are 430 * protected by managed_page_count_lock at runtime. Idealy only 431 * adjust_managed_page_count() should be used instead of directly 432 * touching zone->managed_pages and totalram_pages. 433 */ 434 unsigned long managed_pages; 435 unsigned long spanned_pages; 436 unsigned long present_pages; 437 438 const char *name; 439 440 #ifdef CONFIG_MEMORY_ISOLATION 441 /* 442 * Number of isolated pageblock. It is used to solve incorrect 443 * freepage counting problem due to racy retrieving migratetype 444 * of pageblock. Protected by zone->lock. 445 */ 446 unsigned long nr_isolate_pageblock; 447 #endif 448 449 #ifdef CONFIG_MEMORY_HOTPLUG 450 /* see spanned/present_pages for more description */ 451 seqlock_t span_seqlock; 452 #endif 453 454 int initialized; 455 456 /* Write-intensive fields used from the page allocator */ 457 ZONE_PADDING(_pad1_) 458 459 /* free areas of different sizes */ 460 struct free_area free_area[MAX_ORDER]; 461 462 /* zone flags, see below */ 463 unsigned long flags; 464 465 /* Primarily protects free_area */ 466 spinlock_t lock; 467 468 /* Write-intensive fields used by compaction and vmstats. */ 469 ZONE_PADDING(_pad2_) 470 471 /* 472 * When free pages are below this point, additional steps are taken 473 * when reading the number of free pages to avoid per-cpu counter 474 * drift allowing watermarks to be breached 475 */ 476 unsigned long percpu_drift_mark; 477 478 #if defined CONFIG_COMPACTION || defined CONFIG_CMA 479 /* pfn where compaction free scanner should start */ 480 unsigned long compact_cached_free_pfn; 481 /* pfn where async and sync compaction migration scanner should start */ 482 unsigned long compact_cached_migrate_pfn[2]; 483 #endif 484 485 #ifdef CONFIG_COMPACTION 486 /* 487 * On compaction failure, 1<<compact_defer_shift compactions 488 * are skipped before trying again. The number attempted since 489 * last failure is tracked with compact_considered. 490 */ 491 unsigned int compact_considered; 492 unsigned int compact_defer_shift; 493 int compact_order_failed; 494 #endif 495 496 #if defined CONFIG_COMPACTION || defined CONFIG_CMA 497 /* Set to true when the PG_migrate_skip bits should be cleared */ 498 bool compact_blockskip_flush; 499 #endif 500 501 bool contiguous; 502 503 ZONE_PADDING(_pad3_) 504 /* Zone statistics */ 505 atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS]; 506 atomic_long_t vm_numa_stat[NR_VM_NUMA_STAT_ITEMS]; 507 } ____cacheline_internodealigned_in_smp; 508 509 enum pgdat_flags { 510 PGDAT_CONGESTED, /* pgdat has many dirty pages backed by 511 * a congested BDI 512 */ 513 PGDAT_DIRTY, /* reclaim scanning has recently found 514 * many dirty file pages at the tail 515 * of the LRU. 516 */ 517 PGDAT_WRITEBACK, /* reclaim scanning has recently found 518 * many pages under writeback 519 */ 520 PGDAT_RECLAIM_LOCKED, /* prevents concurrent reclaim */ 521 }; 522 523 static inline unsigned long zone_end_pfn(const struct zone *zone) 524 { 525 return zone->zone_start_pfn + zone->spanned_pages; 526 } 527 528 static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn) 529 { 530 return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone); 531 } 532 533 static inline bool zone_is_initialized(struct zone *zone) 534 { 535 return zone->initialized; 536 } 537 538 static inline bool zone_is_empty(struct zone *zone) 539 { 540 return zone->spanned_pages == 0; 541 } 542 543 /* 544 * Return true if [start_pfn, start_pfn + nr_pages) range has a non-empty 545 * intersection with the given zone 546 */ 547 static inline bool zone_intersects(struct zone *zone, 548 unsigned long start_pfn, unsigned long nr_pages) 549 { 550 if (zone_is_empty(zone)) 551 return false; 552 if (start_pfn >= zone_end_pfn(zone) || 553 start_pfn + nr_pages <= zone->zone_start_pfn) 554 return false; 555 556 return true; 557 } 558 559 /* 560 * The "priority" of VM scanning is how much of the queues we will scan in one 561 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the 562 * queues ("queue_length >> 12") during an aging round. 563 */ 564 #define DEF_PRIORITY 12 565 566 /* Maximum number of zones on a zonelist */ 567 #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES) 568 569 enum { 570 ZONELIST_FALLBACK, /* zonelist with fallback */ 571 #ifdef CONFIG_NUMA 572 /* 573 * The NUMA zonelists are doubled because we need zonelists that 574 * restrict the allocations to a single node for __GFP_THISNODE. 575 */ 576 ZONELIST_NOFALLBACK, /* zonelist without fallback (__GFP_THISNODE) */ 577 #endif 578 MAX_ZONELISTS 579 }; 580 581 /* 582 * This struct contains information about a zone in a zonelist. It is stored 583 * here to avoid dereferences into large structures and lookups of tables 584 */ 585 struct zoneref { 586 struct zone *zone; /* Pointer to actual zone */ 587 int zone_idx; /* zone_idx(zoneref->zone) */ 588 }; 589 590 /* 591 * One allocation request operates on a zonelist. A zonelist 592 * is a list of zones, the first one is the 'goal' of the 593 * allocation, the other zones are fallback zones, in decreasing 594 * priority. 595 * 596 * To speed the reading of the zonelist, the zonerefs contain the zone index 597 * of the entry being read. Helper functions to access information given 598 * a struct zoneref are 599 * 600 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs 601 * zonelist_zone_idx() - Return the index of the zone for an entry 602 * zonelist_node_idx() - Return the index of the node for an entry 603 */ 604 struct zonelist { 605 struct zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1]; 606 }; 607 608 #ifndef CONFIG_DISCONTIGMEM 609 /* The array of struct pages - for discontigmem use pgdat->lmem_map */ 610 extern struct page *mem_map; 611 #endif 612 613 /* 614 * On NUMA machines, each NUMA node would have a pg_data_t to describe 615 * it's memory layout. On UMA machines there is a single pglist_data which 616 * describes the whole memory. 617 * 618 * Memory statistics and page replacement data structures are maintained on a 619 * per-zone basis. 620 */ 621 struct bootmem_data; 622 typedef struct pglist_data { 623 struct zone node_zones[MAX_NR_ZONES]; 624 struct zonelist node_zonelists[MAX_ZONELISTS]; 625 int nr_zones; 626 #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */ 627 struct page *node_mem_map; 628 #ifdef CONFIG_PAGE_EXTENSION 629 struct page_ext *node_page_ext; 630 #endif 631 #endif 632 #ifndef CONFIG_NO_BOOTMEM 633 struct bootmem_data *bdata; 634 #endif 635 #ifdef CONFIG_MEMORY_HOTPLUG 636 /* 637 * Must be held any time you expect node_start_pfn, node_present_pages 638 * or node_spanned_pages stay constant. Holding this will also 639 * guarantee that any pfn_valid() stays that way. 640 * 641 * pgdat_resize_lock() and pgdat_resize_unlock() are provided to 642 * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG. 643 * 644 * Nests above zone->lock and zone->span_seqlock 645 */ 646 spinlock_t node_size_lock; 647 #endif 648 unsigned long node_start_pfn; 649 unsigned long node_present_pages; /* total number of physical pages */ 650 unsigned long node_spanned_pages; /* total size of physical page 651 range, including holes */ 652 int node_id; 653 wait_queue_head_t kswapd_wait; 654 wait_queue_head_t pfmemalloc_wait; 655 struct task_struct *kswapd; /* Protected by 656 mem_hotplug_begin/end() */ 657 int kswapd_order; 658 enum zone_type kswapd_classzone_idx; 659 660 int kswapd_failures; /* Number of 'reclaimed == 0' runs */ 661 662 #ifdef CONFIG_COMPACTION 663 int kcompactd_max_order; 664 enum zone_type kcompactd_classzone_idx; 665 wait_queue_head_t kcompactd_wait; 666 struct task_struct *kcompactd; 667 #endif 668 #ifdef CONFIG_NUMA_BALANCING 669 /* Lock serializing the migrate rate limiting window */ 670 spinlock_t numabalancing_migrate_lock; 671 672 /* Rate limiting time interval */ 673 unsigned long numabalancing_migrate_next_window; 674 675 /* Number of pages migrated during the rate limiting time interval */ 676 unsigned long numabalancing_migrate_nr_pages; 677 #endif 678 /* 679 * This is a per-node reserve of pages that are not available 680 * to userspace allocations. 681 */ 682 unsigned long totalreserve_pages; 683 684 #ifdef CONFIG_NUMA 685 /* 686 * zone reclaim becomes active if more unmapped pages exist. 687 */ 688 unsigned long min_unmapped_pages; 689 unsigned long min_slab_pages; 690 #endif /* CONFIG_NUMA */ 691 692 /* Write-intensive fields used by page reclaim */ 693 ZONE_PADDING(_pad1_) 694 spinlock_t lru_lock; 695 696 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT 697 /* 698 * If memory initialisation on large machines is deferred then this 699 * is the first PFN that needs to be initialised. 700 */ 701 unsigned long first_deferred_pfn; 702 unsigned long static_init_size; 703 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ 704 705 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 706 spinlock_t split_queue_lock; 707 struct list_head split_queue; 708 unsigned long split_queue_len; 709 #endif 710 711 /* Fields commonly accessed by the page reclaim scanner */ 712 struct lruvec lruvec; 713 714 /* 715 * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on 716 * this node's LRU. Maintained by the pageout code. 717 */ 718 unsigned int inactive_ratio; 719 720 unsigned long flags; 721 722 ZONE_PADDING(_pad2_) 723 724 /* Per-node vmstats */ 725 struct per_cpu_nodestat __percpu *per_cpu_nodestats; 726 atomic_long_t vm_stat[NR_VM_NODE_STAT_ITEMS]; 727 } pg_data_t; 728 729 #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages) 730 #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages) 731 #ifdef CONFIG_FLAT_NODE_MEM_MAP 732 #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr)) 733 #else 734 #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr)) 735 #endif 736 #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr)) 737 738 #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn) 739 #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid)) 740 static inline spinlock_t *zone_lru_lock(struct zone *zone) 741 { 742 return &zone->zone_pgdat->lru_lock; 743 } 744 745 static inline struct lruvec *node_lruvec(struct pglist_data *pgdat) 746 { 747 return &pgdat->lruvec; 748 } 749 750 static inline unsigned long pgdat_end_pfn(pg_data_t *pgdat) 751 { 752 return pgdat->node_start_pfn + pgdat->node_spanned_pages; 753 } 754 755 static inline bool pgdat_is_empty(pg_data_t *pgdat) 756 { 757 return !pgdat->node_start_pfn && !pgdat->node_spanned_pages; 758 } 759 760 static inline int zone_id(const struct zone *zone) 761 { 762 struct pglist_data *pgdat = zone->zone_pgdat; 763 764 return zone - pgdat->node_zones; 765 } 766 767 #ifdef CONFIG_ZONE_DEVICE 768 static inline bool is_dev_zone(const struct zone *zone) 769 { 770 return zone_id(zone) == ZONE_DEVICE; 771 } 772 #else 773 static inline bool is_dev_zone(const struct zone *zone) 774 { 775 return false; 776 } 777 #endif 778 779 #include <linux/memory_hotplug.h> 780 781 void build_all_zonelists(pg_data_t *pgdat); 782 void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx); 783 bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, 784 int classzone_idx, unsigned int alloc_flags, 785 long free_pages); 786 bool zone_watermark_ok(struct zone *z, unsigned int order, 787 unsigned long mark, int classzone_idx, 788 unsigned int alloc_flags); 789 bool zone_watermark_ok_safe(struct zone *z, unsigned int order, 790 unsigned long mark, int classzone_idx); 791 enum memmap_context { 792 MEMMAP_EARLY, 793 MEMMAP_HOTPLUG, 794 }; 795 extern void init_currently_empty_zone(struct zone *zone, unsigned long start_pfn, 796 unsigned long size); 797 798 extern void lruvec_init(struct lruvec *lruvec); 799 800 static inline struct pglist_data *lruvec_pgdat(struct lruvec *lruvec) 801 { 802 #ifdef CONFIG_MEMCG 803 return lruvec->pgdat; 804 #else 805 return container_of(lruvec, struct pglist_data, lruvec); 806 #endif 807 } 808 809 extern unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru, int zone_idx); 810 811 #ifdef CONFIG_HAVE_MEMORY_PRESENT 812 void memory_present(int nid, unsigned long start, unsigned long end); 813 #else 814 static inline void memory_present(int nid, unsigned long start, unsigned long end) {} 815 #endif 816 817 #ifdef CONFIG_HAVE_MEMORYLESS_NODES 818 int local_memory_node(int node_id); 819 #else 820 static inline int local_memory_node(int node_id) { return node_id; }; 821 #endif 822 823 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE 824 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long); 825 #endif 826 827 /* 828 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc. 829 */ 830 #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones) 831 832 /* 833 * Returns true if a zone has pages managed by the buddy allocator. 834 * All the reclaim decisions have to use this function rather than 835 * populated_zone(). If the whole zone is reserved then we can easily 836 * end up with populated_zone() && !managed_zone(). 837 */ 838 static inline bool managed_zone(struct zone *zone) 839 { 840 return zone->managed_pages; 841 } 842 843 /* Returns true if a zone has memory */ 844 static inline bool populated_zone(struct zone *zone) 845 { 846 return zone->present_pages; 847 } 848 849 extern int movable_zone; 850 851 #ifdef CONFIG_HIGHMEM 852 static inline int zone_movable_is_highmem(void) 853 { 854 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP 855 return movable_zone == ZONE_HIGHMEM; 856 #else 857 return (ZONE_MOVABLE - 1) == ZONE_HIGHMEM; 858 #endif 859 } 860 #endif 861 862 static inline int is_highmem_idx(enum zone_type idx) 863 { 864 #ifdef CONFIG_HIGHMEM 865 return (idx == ZONE_HIGHMEM || 866 (idx == ZONE_MOVABLE && zone_movable_is_highmem())); 867 #else 868 return 0; 869 #endif 870 } 871 872 /** 873 * is_highmem - helper function to quickly check if a struct zone is a 874 * highmem zone or not. This is an attempt to keep references 875 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum. 876 * @zone - pointer to struct zone variable 877 */ 878 static inline int is_highmem(struct zone *zone) 879 { 880 #ifdef CONFIG_HIGHMEM 881 return is_highmem_idx(zone_idx(zone)); 882 #else 883 return 0; 884 #endif 885 } 886 887 /* These two functions are used to setup the per zone pages min values */ 888 struct ctl_table; 889 int min_free_kbytes_sysctl_handler(struct ctl_table *, int, 890 void __user *, size_t *, loff_t *); 891 int watermark_scale_factor_sysctl_handler(struct ctl_table *, int, 892 void __user *, size_t *, loff_t *); 893 extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1]; 894 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int, 895 void __user *, size_t *, loff_t *); 896 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int, 897 void __user *, size_t *, loff_t *); 898 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int, 899 void __user *, size_t *, loff_t *); 900 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int, 901 void __user *, size_t *, loff_t *); 902 903 extern int numa_zonelist_order_handler(struct ctl_table *, int, 904 void __user *, size_t *, loff_t *); 905 extern char numa_zonelist_order[]; 906 #define NUMA_ZONELIST_ORDER_LEN 16 907 908 #ifndef CONFIG_NEED_MULTIPLE_NODES 909 910 extern struct pglist_data contig_page_data; 911 #define NODE_DATA(nid) (&contig_page_data) 912 #define NODE_MEM_MAP(nid) mem_map 913 914 #else /* CONFIG_NEED_MULTIPLE_NODES */ 915 916 #include <asm/mmzone.h> 917 918 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 919 920 extern struct pglist_data *first_online_pgdat(void); 921 extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat); 922 extern struct zone *next_zone(struct zone *zone); 923 924 /** 925 * for_each_online_pgdat - helper macro to iterate over all online nodes 926 * @pgdat - pointer to a pg_data_t variable 927 */ 928 #define for_each_online_pgdat(pgdat) \ 929 for (pgdat = first_online_pgdat(); \ 930 pgdat; \ 931 pgdat = next_online_pgdat(pgdat)) 932 /** 933 * for_each_zone - helper macro to iterate over all memory zones 934 * @zone - pointer to struct zone variable 935 * 936 * The user only needs to declare the zone variable, for_each_zone 937 * fills it in. 938 */ 939 #define for_each_zone(zone) \ 940 for (zone = (first_online_pgdat())->node_zones; \ 941 zone; \ 942 zone = next_zone(zone)) 943 944 #define for_each_populated_zone(zone) \ 945 for (zone = (first_online_pgdat())->node_zones; \ 946 zone; \ 947 zone = next_zone(zone)) \ 948 if (!populated_zone(zone)) \ 949 ; /* do nothing */ \ 950 else 951 952 static inline struct zone *zonelist_zone(struct zoneref *zoneref) 953 { 954 return zoneref->zone; 955 } 956 957 static inline int zonelist_zone_idx(struct zoneref *zoneref) 958 { 959 return zoneref->zone_idx; 960 } 961 962 static inline int zonelist_node_idx(struct zoneref *zoneref) 963 { 964 #ifdef CONFIG_NUMA 965 /* zone_to_nid not available in this context */ 966 return zoneref->zone->node; 967 #else 968 return 0; 969 #endif /* CONFIG_NUMA */ 970 } 971 972 struct zoneref *__next_zones_zonelist(struct zoneref *z, 973 enum zone_type highest_zoneidx, 974 nodemask_t *nodes); 975 976 /** 977 * next_zones_zonelist - Returns the next zone at or below highest_zoneidx within the allowed nodemask using a cursor within a zonelist as a starting point 978 * @z - The cursor used as a starting point for the search 979 * @highest_zoneidx - The zone index of the highest zone to return 980 * @nodes - An optional nodemask to filter the zonelist with 981 * 982 * This function returns the next zone at or below a given zone index that is 983 * within the allowed nodemask using a cursor as the starting point for the 984 * search. The zoneref returned is a cursor that represents the current zone 985 * being examined. It should be advanced by one before calling 986 * next_zones_zonelist again. 987 */ 988 static __always_inline struct zoneref *next_zones_zonelist(struct zoneref *z, 989 enum zone_type highest_zoneidx, 990 nodemask_t *nodes) 991 { 992 if (likely(!nodes && zonelist_zone_idx(z) <= highest_zoneidx)) 993 return z; 994 return __next_zones_zonelist(z, highest_zoneidx, nodes); 995 } 996 997 /** 998 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist 999 * @zonelist - The zonelist to search for a suitable zone 1000 * @highest_zoneidx - The zone index of the highest zone to return 1001 * @nodes - An optional nodemask to filter the zonelist with 1002 * @return - Zoneref pointer for the first suitable zone found (see below) 1003 * 1004 * This function returns the first zone at or below a given zone index that is 1005 * within the allowed nodemask. The zoneref returned is a cursor that can be 1006 * used to iterate the zonelist with next_zones_zonelist by advancing it by 1007 * one before calling. 1008 * 1009 * When no eligible zone is found, zoneref->zone is NULL (zoneref itself is 1010 * never NULL). This may happen either genuinely, or due to concurrent nodemask 1011 * update due to cpuset modification. 1012 */ 1013 static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist, 1014 enum zone_type highest_zoneidx, 1015 nodemask_t *nodes) 1016 { 1017 return next_zones_zonelist(zonelist->_zonerefs, 1018 highest_zoneidx, nodes); 1019 } 1020 1021 /** 1022 * for_each_zone_zonelist_nodemask - helper macro to iterate over valid zones in a zonelist at or below a given zone index and within a nodemask 1023 * @zone - The current zone in the iterator 1024 * @z - The current pointer within zonelist->zones being iterated 1025 * @zlist - The zonelist being iterated 1026 * @highidx - The zone index of the highest zone to return 1027 * @nodemask - Nodemask allowed by the allocator 1028 * 1029 * This iterator iterates though all zones at or below a given zone index and 1030 * within a given nodemask 1031 */ 1032 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \ 1033 for (z = first_zones_zonelist(zlist, highidx, nodemask), zone = zonelist_zone(z); \ 1034 zone; \ 1035 z = next_zones_zonelist(++z, highidx, nodemask), \ 1036 zone = zonelist_zone(z)) 1037 1038 #define for_next_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \ 1039 for (zone = z->zone; \ 1040 zone; \ 1041 z = next_zones_zonelist(++z, highidx, nodemask), \ 1042 zone = zonelist_zone(z)) 1043 1044 1045 /** 1046 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index 1047 * @zone - The current zone in the iterator 1048 * @z - The current pointer within zonelist->zones being iterated 1049 * @zlist - The zonelist being iterated 1050 * @highidx - The zone index of the highest zone to return 1051 * 1052 * This iterator iterates though all zones at or below a given zone index. 1053 */ 1054 #define for_each_zone_zonelist(zone, z, zlist, highidx) \ 1055 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL) 1056 1057 #ifdef CONFIG_SPARSEMEM 1058 #include <asm/sparsemem.h> 1059 #endif 1060 1061 #if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \ 1062 !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) 1063 static inline unsigned long early_pfn_to_nid(unsigned long pfn) 1064 { 1065 BUILD_BUG_ON(IS_ENABLED(CONFIG_NUMA)); 1066 return 0; 1067 } 1068 #endif 1069 1070 #ifdef CONFIG_FLATMEM 1071 #define pfn_to_nid(pfn) (0) 1072 #endif 1073 1074 #ifdef CONFIG_SPARSEMEM 1075 1076 /* 1077 * SECTION_SHIFT #bits space required to store a section # 1078 * 1079 * PA_SECTION_SHIFT physical address to/from section number 1080 * PFN_SECTION_SHIFT pfn to/from section number 1081 */ 1082 #define PA_SECTION_SHIFT (SECTION_SIZE_BITS) 1083 #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT) 1084 1085 #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT) 1086 1087 #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT) 1088 #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1)) 1089 1090 #define SECTION_BLOCKFLAGS_BITS \ 1091 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS) 1092 1093 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS 1094 #error Allocator MAX_ORDER exceeds SECTION_SIZE 1095 #endif 1096 1097 static inline unsigned long pfn_to_section_nr(unsigned long pfn) 1098 { 1099 return pfn >> PFN_SECTION_SHIFT; 1100 } 1101 static inline unsigned long section_nr_to_pfn(unsigned long sec) 1102 { 1103 return sec << PFN_SECTION_SHIFT; 1104 } 1105 1106 #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK) 1107 #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK) 1108 1109 struct page; 1110 struct page_ext; 1111 struct mem_section { 1112 /* 1113 * This is, logically, a pointer to an array of struct 1114 * pages. However, it is stored with some other magic. 1115 * (see sparse.c::sparse_init_one_section()) 1116 * 1117 * Additionally during early boot we encode node id of 1118 * the location of the section here to guide allocation. 1119 * (see sparse.c::memory_present()) 1120 * 1121 * Making it a UL at least makes someone do a cast 1122 * before using it wrong. 1123 */ 1124 unsigned long section_mem_map; 1125 1126 /* See declaration of similar field in struct zone */ 1127 unsigned long *pageblock_flags; 1128 #ifdef CONFIG_PAGE_EXTENSION 1129 /* 1130 * If SPARSEMEM, pgdat doesn't have page_ext pointer. We use 1131 * section. (see page_ext.h about this.) 1132 */ 1133 struct page_ext *page_ext; 1134 unsigned long pad; 1135 #endif 1136 /* 1137 * WARNING: mem_section must be a power-of-2 in size for the 1138 * calculation and use of SECTION_ROOT_MASK to make sense. 1139 */ 1140 }; 1141 1142 #ifdef CONFIG_SPARSEMEM_EXTREME 1143 #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section)) 1144 #else 1145 #define SECTIONS_PER_ROOT 1 1146 #endif 1147 1148 #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT) 1149 #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT) 1150 #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1) 1151 1152 #ifdef CONFIG_SPARSEMEM_EXTREME 1153 extern struct mem_section *mem_section[NR_SECTION_ROOTS]; 1154 #else 1155 extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT]; 1156 #endif 1157 1158 static inline struct mem_section *__nr_to_section(unsigned long nr) 1159 { 1160 if (!mem_section[SECTION_NR_TO_ROOT(nr)]) 1161 return NULL; 1162 return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK]; 1163 } 1164 extern int __section_nr(struct mem_section* ms); 1165 extern unsigned long usemap_size(void); 1166 1167 /* 1168 * We use the lower bits of the mem_map pointer to store 1169 * a little bit of information. There should be at least 1170 * 3 bits here due to 32-bit alignment. 1171 */ 1172 #define SECTION_MARKED_PRESENT (1UL<<0) 1173 #define SECTION_HAS_MEM_MAP (1UL<<1) 1174 #define SECTION_IS_ONLINE (1UL<<2) 1175 #define SECTION_MAP_LAST_BIT (1UL<<3) 1176 #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1)) 1177 #define SECTION_NID_SHIFT 3 1178 1179 static inline struct page *__section_mem_map_addr(struct mem_section *section) 1180 { 1181 unsigned long map = section->section_mem_map; 1182 map &= SECTION_MAP_MASK; 1183 return (struct page *)map; 1184 } 1185 1186 static inline int present_section(struct mem_section *section) 1187 { 1188 return (section && (section->section_mem_map & SECTION_MARKED_PRESENT)); 1189 } 1190 1191 static inline int present_section_nr(unsigned long nr) 1192 { 1193 return present_section(__nr_to_section(nr)); 1194 } 1195 1196 static inline int valid_section(struct mem_section *section) 1197 { 1198 return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP)); 1199 } 1200 1201 static inline int valid_section_nr(unsigned long nr) 1202 { 1203 return valid_section(__nr_to_section(nr)); 1204 } 1205 1206 static inline int online_section(struct mem_section *section) 1207 { 1208 return (section && (section->section_mem_map & SECTION_IS_ONLINE)); 1209 } 1210 1211 static inline int online_section_nr(unsigned long nr) 1212 { 1213 return online_section(__nr_to_section(nr)); 1214 } 1215 1216 #ifdef CONFIG_MEMORY_HOTPLUG 1217 void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn); 1218 #ifdef CONFIG_MEMORY_HOTREMOVE 1219 void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn); 1220 #endif 1221 #endif 1222 1223 static inline struct mem_section *__pfn_to_section(unsigned long pfn) 1224 { 1225 return __nr_to_section(pfn_to_section_nr(pfn)); 1226 } 1227 1228 extern int __highest_present_section_nr; 1229 1230 #ifndef CONFIG_HAVE_ARCH_PFN_VALID 1231 static inline int pfn_valid(unsigned long pfn) 1232 { 1233 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS) 1234 return 0; 1235 return valid_section(__nr_to_section(pfn_to_section_nr(pfn))); 1236 } 1237 #endif 1238 1239 static inline int pfn_present(unsigned long pfn) 1240 { 1241 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS) 1242 return 0; 1243 return present_section(__nr_to_section(pfn_to_section_nr(pfn))); 1244 } 1245 1246 /* 1247 * These are _only_ used during initialisation, therefore they 1248 * can use __initdata ... They could have names to indicate 1249 * this restriction. 1250 */ 1251 #ifdef CONFIG_NUMA 1252 #define pfn_to_nid(pfn) \ 1253 ({ \ 1254 unsigned long __pfn_to_nid_pfn = (pfn); \ 1255 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \ 1256 }) 1257 #else 1258 #define pfn_to_nid(pfn) (0) 1259 #endif 1260 1261 #define early_pfn_valid(pfn) pfn_valid(pfn) 1262 void sparse_init(void); 1263 #else 1264 #define sparse_init() do {} while (0) 1265 #define sparse_index_init(_sec, _nid) do {} while (0) 1266 #endif /* CONFIG_SPARSEMEM */ 1267 1268 /* 1269 * During memory init memblocks map pfns to nids. The search is expensive and 1270 * this caches recent lookups. The implementation of __early_pfn_to_nid 1271 * may treat start/end as pfns or sections. 1272 */ 1273 struct mminit_pfnnid_cache { 1274 unsigned long last_start; 1275 unsigned long last_end; 1276 int last_nid; 1277 }; 1278 1279 #ifndef early_pfn_valid 1280 #define early_pfn_valid(pfn) (1) 1281 #endif 1282 1283 void memory_present(int nid, unsigned long start, unsigned long end); 1284 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long); 1285 1286 /* 1287 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we 1288 * need to check pfn validility within that MAX_ORDER_NR_PAGES block. 1289 * pfn_valid_within() should be used in this case; we optimise this away 1290 * when we have no holes within a MAX_ORDER_NR_PAGES block. 1291 */ 1292 #ifdef CONFIG_HOLES_IN_ZONE 1293 #define pfn_valid_within(pfn) pfn_valid(pfn) 1294 #else 1295 #define pfn_valid_within(pfn) (1) 1296 #endif 1297 1298 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL 1299 /* 1300 * pfn_valid() is meant to be able to tell if a given PFN has valid memmap 1301 * associated with it or not. This means that a struct page exists for this 1302 * pfn. The caller cannot assume the page is fully initialized in general. 1303 * Hotplugable pages might not have been onlined yet. pfn_to_online_page() 1304 * will ensure the struct page is fully online and initialized. Special pages 1305 * (e.g. ZONE_DEVICE) are never onlined and should be treated accordingly. 1306 * 1307 * In FLATMEM, it is expected that holes always have valid memmap as long as 1308 * there is valid PFNs either side of the hole. In SPARSEMEM, it is assumed 1309 * that a valid section has a memmap for the entire section. 1310 * 1311 * However, an ARM, and maybe other embedded architectures in the future 1312 * free memmap backing holes to save memory on the assumption the memmap is 1313 * never used. The page_zone linkages are then broken even though pfn_valid() 1314 * returns true. A walker of the full memmap must then do this additional 1315 * check to ensure the memmap they are looking at is sane by making sure 1316 * the zone and PFN linkages are still valid. This is expensive, but walkers 1317 * of the full memmap are extremely rare. 1318 */ 1319 bool memmap_valid_within(unsigned long pfn, 1320 struct page *page, struct zone *zone); 1321 #else 1322 static inline bool memmap_valid_within(unsigned long pfn, 1323 struct page *page, struct zone *zone) 1324 { 1325 return true; 1326 } 1327 #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */ 1328 1329 #endif /* !__GENERATING_BOUNDS.H */ 1330 #endif /* !__ASSEMBLY__ */ 1331 #endif /* _LINUX_MMZONE_H */ 1332