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- /* SPDX-License-Identifier: GPL-2.0 */
- #ifndef _LINUX_MMZONE_H
- #define _LINUX_MMZONE_H
- #ifndef __ASSEMBLY__
- #ifndef __GENERATING_BOUNDS_H
- #include <linux/spinlock.h>
- #include <linux/list.h>
- #include <linux/wait.h>
- #include <linux/bitops.h>
- #include <linux/cache.h>
- #include <linux/threads.h>
- #include <linux/numa.h>
- #include <linux/init.h>
- #include <linux/seqlock.h>
- #include <linux/nodemask.h>
- #include <linux/pageblock-flags.h>
- #include <linux/page-flags-layout.h>
- #include <linux/atomic.h>
- #include <linux/mm_types.h>
- #include <linux/page-flags.h>
- #include <linux/android_kabi.h>
- #include <asm/page.h>
- /* Free memory management - zoned buddy allocator. */
- #ifndef CONFIG_FORCE_MAX_ZONEORDER
- #define MAX_ORDER 11
- #else
- #define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
- #endif
- #define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
- /*
- * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed
- * costly to service. That is between allocation orders which should
- * coalesce naturally under reasonable reclaim pressure and those which
- * will not.
- */
- #define PAGE_ALLOC_COSTLY_ORDER 3
- #define MAX_KSWAPD_THREADS 16
- enum migratetype {
- MIGRATE_UNMOVABLE,
- MIGRATE_MOVABLE,
- MIGRATE_RECLAIMABLE,
- #ifdef CONFIG_CMA
- /*
- * MIGRATE_CMA migration type is designed to mimic the way
- * ZONE_MOVABLE works. Only movable pages can be allocated
- * from MIGRATE_CMA pageblocks and page allocator never
- * implicitly change migration type of MIGRATE_CMA pageblock.
- *
- * The way to use it is to change migratetype of a range of
- * pageblocks to MIGRATE_CMA which can be done by
- * __free_pageblock_cma() function. What is important though
- * is that a range of pageblocks must be aligned to
- * MAX_ORDER_NR_PAGES should biggest page be bigger then
- * a single pageblock.
- */
- MIGRATE_CMA,
- #endif
- MIGRATE_PCPTYPES, /* the number of types on the pcp lists */
- MIGRATE_HIGHATOMIC = MIGRATE_PCPTYPES,
- #ifdef CONFIG_MEMORY_ISOLATION
- MIGRATE_ISOLATE, /* can't allocate from here */
- #endif
- MIGRATE_TYPES
- };
- /* In mm/page_alloc.c; keep in sync also with show_migration_types() there */
- extern const char * const migratetype_names[MIGRATE_TYPES];
- #ifdef CONFIG_CMA
- # define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
- # define is_migrate_cma_page(_page) (get_pageblock_migratetype(_page) == MIGRATE_CMA)
- # define get_cma_migrate_type() MIGRATE_CMA
- #else
- # define is_migrate_cma(migratetype) false
- # define is_migrate_cma_page(_page) false
- # define get_cma_migrate_type() MIGRATE_MOVABLE
- #endif
- static inline bool is_migrate_movable(int mt)
- {
- return is_migrate_cma(mt) || mt == MIGRATE_MOVABLE;
- }
- #define for_each_migratetype_order(order, type) \
- for (order = 0; order < MAX_ORDER; order++) \
- for (type = 0; type < MIGRATE_TYPES; type++)
- extern int page_group_by_mobility_disabled;
- #define MIGRATETYPE_MASK ((1UL << PB_migratetype_bits) - 1)
- #define get_pageblock_migratetype(page) \
- get_pfnblock_flags_mask(page, page_to_pfn(page), MIGRATETYPE_MASK)
- struct free_area {
- struct list_head free_list[MIGRATE_TYPES];
- unsigned long nr_free;
- };
- static inline struct page *get_page_from_free_area(struct free_area *area,
- int migratetype)
- {
- return list_first_entry_or_null(&area->free_list[migratetype],
- struct page, lru);
- }
- static inline bool free_area_empty(struct free_area *area, int migratetype)
- {
- return list_empty(&area->free_list[migratetype]);
- }
- struct pglist_data;
- /*
- * zone->lock and the zone lru_lock are two of the hottest locks in the kernel.
- * So add a wild amount of padding here to ensure that they fall into separate
- * cachelines. There are very few zone structures in the machine, so space
- * consumption is not a concern here.
- */
- #if defined(CONFIG_SMP)
- struct zone_padding {
- char x[0];
- } ____cacheline_internodealigned_in_smp;
- #define ZONE_PADDING(name) struct zone_padding name;
- #else
- #define ZONE_PADDING(name)
- #endif
- #ifdef CONFIG_NUMA
- enum numa_stat_item {
- NUMA_HIT, /* allocated in intended node */
- NUMA_MISS, /* allocated in non intended node */
- NUMA_FOREIGN, /* was intended here, hit elsewhere */
- NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */
- NUMA_LOCAL, /* allocation from local node */
- NUMA_OTHER, /* allocation from other node */
- NR_VM_NUMA_STAT_ITEMS
- };
- #else
- #define NR_VM_NUMA_STAT_ITEMS 0
- #endif
- enum zone_stat_item {
- /* First 128 byte cacheline (assuming 64 bit words) */
- NR_FREE_PAGES,
- NR_ZONE_LRU_BASE, /* Used only for compaction and reclaim retry */
- NR_ZONE_INACTIVE_ANON = NR_ZONE_LRU_BASE,
- NR_ZONE_ACTIVE_ANON,
- NR_ZONE_INACTIVE_FILE,
- NR_ZONE_ACTIVE_FILE,
- NR_ZONE_UNEVICTABLE,
- NR_ZONE_WRITE_PENDING, /* Count of dirty, writeback and unstable pages */
- NR_MLOCK, /* mlock()ed pages found and moved off LRU */
- NR_PAGETABLE, /* used for pagetables */
- /* Second 128 byte cacheline */
- NR_BOUNCE,
- NR_ZSPAGES, /* allocated in zsmalloc */
- NR_FREE_CMA_PAGES,
- NR_VM_ZONE_STAT_ITEMS };
- enum node_stat_item {
- NR_LRU_BASE,
- NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
- NR_ACTIVE_ANON, /* " " " " " */
- NR_INACTIVE_FILE, /* " " " " " */
- NR_ACTIVE_FILE, /* " " " " " */
- NR_UNEVICTABLE, /* " " " " " */
- NR_SLAB_RECLAIMABLE_B,
- NR_SLAB_UNRECLAIMABLE_B,
- NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
- NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
- WORKINGSET_NODES,
- WORKINGSET_REFAULT_BASE,
- WORKINGSET_REFAULT_ANON = WORKINGSET_REFAULT_BASE,
- WORKINGSET_REFAULT_FILE,
- WORKINGSET_ACTIVATE_BASE,
- WORKINGSET_ACTIVATE_ANON = WORKINGSET_ACTIVATE_BASE,
- WORKINGSET_ACTIVATE_FILE,
- WORKINGSET_RESTORE_BASE,
- WORKINGSET_RESTORE_ANON = WORKINGSET_RESTORE_BASE,
- WORKINGSET_RESTORE_FILE,
- WORKINGSET_NODERECLAIM,
- NR_ANON_MAPPED, /* Mapped anonymous pages */
- NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
- only modified from process context */
- NR_FILE_PAGES,
- NR_FILE_DIRTY,
- NR_WRITEBACK,
- NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
- NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */
- NR_SHMEM_THPS,
- NR_SHMEM_PMDMAPPED,
- NR_FILE_THPS,
- NR_FILE_PMDMAPPED,
- NR_ANON_THPS,
- NR_VMSCAN_WRITE,
- NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
- NR_DIRTIED, /* page dirtyings since bootup */
- NR_WRITTEN, /* page writings since bootup */
- NR_KERNEL_MISC_RECLAIMABLE, /* reclaimable non-slab kernel pages */
- NR_FOLL_PIN_ACQUIRED, /* via: pin_user_page(), gup flag: FOLL_PIN */
- NR_FOLL_PIN_RELEASED, /* pages returned via unpin_user_page() */
- NR_KERNEL_STACK_KB, /* measured in KiB */
- #if IS_ENABLED(CONFIG_SHADOW_CALL_STACK)
- NR_KERNEL_SCS_KB, /* measured in KiB */
- #endif
- NR_VM_NODE_STAT_ITEMS
- };
- /*
- * Returns true if the value is measured in bytes (most vmstat values are
- * measured in pages). This defines the API part, the internal representation
- * might be different.
- */
- static __always_inline bool vmstat_item_in_bytes(int idx)
- {
- /*
- * Global and per-node slab counters track slab pages.
- * It's expected that changes are multiples of PAGE_SIZE.
- * Internally values are stored in pages.
- *
- * Per-memcg and per-lruvec counters track memory, consumed
- * by individual slab objects. These counters are actually
- * byte-precise.
- */
- return (idx == NR_SLAB_RECLAIMABLE_B ||
- idx == NR_SLAB_UNRECLAIMABLE_B);
- }
- /*
- * We do arithmetic on the LRU lists in various places in the code,
- * so it is important to keep the active lists LRU_ACTIVE higher in
- * the array than the corresponding inactive lists, and to keep
- * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
- *
- * This has to be kept in sync with the statistics in zone_stat_item
- * above and the descriptions in vmstat_text in mm/vmstat.c
- */
- #define LRU_BASE 0
- #define LRU_ACTIVE 1
- #define LRU_FILE 2
- enum lru_list {
- LRU_INACTIVE_ANON = LRU_BASE,
- LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE,
- LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE,
- LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE,
- LRU_UNEVICTABLE,
- NR_LRU_LISTS
- };
- #define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
- #define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
- static inline bool is_file_lru(enum lru_list lru)
- {
- return (lru == LRU_INACTIVE_FILE || lru == LRU_ACTIVE_FILE);
- }
- static inline bool is_active_lru(enum lru_list lru)
- {
- return (lru == LRU_ACTIVE_ANON || lru == LRU_ACTIVE_FILE);
- }
- #define ANON_AND_FILE 2
- enum lruvec_flags {
- LRUVEC_CONGESTED, /* lruvec has many dirty pages
- * backed by a congested BDI
- */
- };
- struct lruvec {
- struct list_head lists[NR_LRU_LISTS];
- /*
- * These track the cost of reclaiming one LRU - file or anon -
- * over the other. As the observed cost of reclaiming one LRU
- * increases, the reclaim scan balance tips toward the other.
- */
- unsigned long anon_cost;
- unsigned long file_cost;
- /* Non-resident age, driven by LRU movement */
- atomic_long_t nonresident_age;
- /* Refaults at the time of last reclaim cycle */
- unsigned long refaults[ANON_AND_FILE];
- /* Various lruvec state flags (enum lruvec_flags) */
- unsigned long flags;
- #ifdef CONFIG_MEMCG
- struct pglist_data *pgdat;
- #endif
- };
- /* Isolate unmapped pages */
- #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
- /* Isolate for asynchronous migration */
- #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
- /* Isolate unevictable pages */
- #define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
- /* LRU Isolation modes. */
- typedef unsigned __bitwise isolate_mode_t;
- enum zone_watermarks {
- WMARK_MIN,
- WMARK_LOW,
- WMARK_HIGH,
- NR_WMARK
- };
- #define min_wmark_pages(z) (z->_watermark[WMARK_MIN] + z->watermark_boost)
- #define low_wmark_pages(z) (z->_watermark[WMARK_LOW] + z->watermark_boost)
- #define high_wmark_pages(z) (z->_watermark[WMARK_HIGH] + z->watermark_boost)
- #define wmark_pages(z, i) (z->_watermark[i] + z->watermark_boost)
- struct per_cpu_pages {
- int count; /* number of pages in the list */
- int high; /* high watermark, emptying needed */
- int batch; /* chunk size for buddy add/remove */
- /* Lists of pages, one per migrate type stored on the pcp-lists */
- struct list_head lists[MIGRATE_PCPTYPES];
- };
- struct per_cpu_pageset {
- struct per_cpu_pages pcp;
- #ifdef CONFIG_NUMA
- s8 expire;
- u16 vm_numa_stat_diff[NR_VM_NUMA_STAT_ITEMS];
- #endif
- #ifdef CONFIG_SMP
- s8 stat_threshold;
- s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
- #endif
- };
- struct per_cpu_nodestat {
- s8 stat_threshold;
- s8 vm_node_stat_diff[NR_VM_NODE_STAT_ITEMS];
- };
- #endif /* !__GENERATING_BOUNDS.H */
- enum zone_type {
- /*
- * ZONE_DMA and ZONE_DMA32 are used when there are peripherals not able
- * to DMA to all of the addressable memory (ZONE_NORMAL).
- * On architectures where this area covers the whole 32 bit address
- * space ZONE_DMA32 is used. ZONE_DMA is left for the ones with smaller
- * DMA addressing constraints. This distinction is important as a 32bit
- * DMA mask is assumed when ZONE_DMA32 is defined. Some 64-bit
- * platforms may need both zones as they support peripherals with
- * different DMA addressing limitations.
- */
- #ifdef CONFIG_ZONE_DMA
- ZONE_DMA,
- #endif
- #ifdef CONFIG_ZONE_DMA32
- ZONE_DMA32,
- #endif
- /*
- * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
- * performed on pages in ZONE_NORMAL if the DMA devices support
- * transfers to all addressable memory.
- */
- ZONE_NORMAL,
- #ifdef CONFIG_HIGHMEM
- /*
- * A memory area that is only addressable by the kernel through
- * mapping portions into its own address space. This is for example
- * used by i386 to allow the kernel to address the memory beyond
- * 900MB. The kernel will set up special mappings (page
- * table entries on i386) for each page that the kernel needs to
- * access.
- */
- ZONE_HIGHMEM,
- #endif
- /*
- * ZONE_MOVABLE is similar to ZONE_NORMAL, except that it contains
- * movable pages with few exceptional cases described below. Main use
- * cases for ZONE_MOVABLE are to make memory offlining/unplug more
- * likely to succeed, and to locally limit unmovable allocations - e.g.,
- * to increase the number of THP/huge pages. Notable special cases are:
- *
- * 1. Pinned pages: (long-term) pinning of movable pages might
- * essentially turn such pages unmovable. Memory offlining might
- * retry a long time.
- * 2. memblock allocations: kernelcore/movablecore setups might create
- * situations where ZONE_MOVABLE contains unmovable allocations
- * after boot. Memory offlining and allocations fail early.
- * 3. Memory holes: kernelcore/movablecore setups might create very rare
- * situations where ZONE_MOVABLE contains memory holes after boot,
- * for example, if we have sections that are only partially
- * populated. Memory offlining and allocations fail early.
- * 4. PG_hwpoison pages: while poisoned pages can be skipped during
- * memory offlining, such pages cannot be allocated.
- * 5. Unmovable PG_offline pages: in paravirtualized environments,
- * hotplugged memory blocks might only partially be managed by the
- * buddy (e.g., via XEN-balloon, Hyper-V balloon, virtio-mem). The
- * parts not manged by the buddy are unmovable PG_offline pages. In
- * some cases (virtio-mem), such pages can be skipped during
- * memory offlining, however, cannot be moved/allocated. These
- * techniques might use alloc_contig_range() to hide previously
- * exposed pages from the buddy again (e.g., to implement some sort
- * of memory unplug in virtio-mem).
- *
- * In general, no unmovable allocations that degrade memory offlining
- * should end up in ZONE_MOVABLE. Allocators (like alloc_contig_range())
- * have to expect that migrating pages in ZONE_MOVABLE can fail (even
- * if has_unmovable_pages() states that there are no unmovable pages,
- * there can be false negatives).
- */
- ZONE_MOVABLE,
- #ifdef CONFIG_ZONE_DEVICE
- ZONE_DEVICE,
- #endif
- __MAX_NR_ZONES
- };
- #ifndef __GENERATING_BOUNDS_H
- #define ASYNC_AND_SYNC 2
- struct zone {
- /* Read-mostly fields */
- /* zone watermarks, access with *_wmark_pages(zone) macros */
- unsigned long _watermark[NR_WMARK];
- unsigned long watermark_boost;
- unsigned long nr_reserved_highatomic;
- /*
- * We don't know if the memory that we're going to allocate will be
- * freeable or/and it will be released eventually, so to avoid totally
- * wasting several GB of ram we must reserve some of the lower zone
- * memory (otherwise we risk to run OOM on the lower zones despite
- * there being tons of freeable ram on the higher zones). This array is
- * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl
- * changes.
- */
- long lowmem_reserve[MAX_NR_ZONES];
- #ifdef CONFIG_NEED_MULTIPLE_NODES
- int node;
- #endif
- struct pglist_data *zone_pgdat;
- struct per_cpu_pageset __percpu *pageset;
- #ifndef CONFIG_SPARSEMEM
- /*
- * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
- * In SPARSEMEM, this map is stored in struct mem_section
- */
- unsigned long *pageblock_flags;
- #endif /* CONFIG_SPARSEMEM */
- /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
- unsigned long zone_start_pfn;
- /*
- * spanned_pages is the total pages spanned by the zone, including
- * holes, which is calculated as:
- * spanned_pages = zone_end_pfn - zone_start_pfn;
- *
- * present_pages is physical pages existing within the zone, which
- * is calculated as:
- * present_pages = spanned_pages - absent_pages(pages in holes);
- *
- * managed_pages is present pages managed by the buddy system, which
- * is calculated as (reserved_pages includes pages allocated by the
- * bootmem allocator):
- * managed_pages = present_pages - reserved_pages;
- *
- * cma pages is present pages that are assigned for CMA use
- * (MIGRATE_CMA).
- *
- * So present_pages may be used by memory hotplug or memory power
- * management logic to figure out unmanaged pages by checking
- * (present_pages - managed_pages). And managed_pages should be used
- * by page allocator and vm scanner to calculate all kinds of watermarks
- * and thresholds.
- *
- * Locking rules:
- *
- * zone_start_pfn and spanned_pages are protected by span_seqlock.
- * It is a seqlock because it has to be read outside of zone->lock,
- * and it is done in the main allocator path. But, it is written
- * quite infrequently.
- *
- * The span_seq lock is declared along with zone->lock because it is
- * frequently read in proximity to zone->lock. It's good to
- * give them a chance of being in the same cacheline.
- *
- * Write access to present_pages at runtime should be protected by
- * mem_hotplug_begin/end(). Any reader who can't tolerant drift of
- * present_pages should get_online_mems() to get a stable value.
- */
- atomic_long_t managed_pages;
- unsigned long spanned_pages;
- unsigned long present_pages;
- #ifdef CONFIG_CMA
- unsigned long cma_pages;
- #endif
- const char *name;
- #ifdef CONFIG_MEMORY_ISOLATION
- /*
- * Number of isolated pageblock. It is used to solve incorrect
- * freepage counting problem due to racy retrieving migratetype
- * of pageblock. Protected by zone->lock.
- */
- unsigned long nr_isolate_pageblock;
- #endif
- #ifdef CONFIG_MEMORY_HOTPLUG
- /* see spanned/present_pages for more description */
- seqlock_t span_seqlock;
- #endif
- int initialized;
- /* Write-intensive fields used from the page allocator */
- ZONE_PADDING(_pad1_)
- /* free areas of different sizes */
- struct free_area free_area[MAX_ORDER];
- /* zone flags, see below */
- unsigned long flags;
- /* Primarily protects free_area */
- spinlock_t lock;
- /* Write-intensive fields used by compaction and vmstats. */
- ZONE_PADDING(_pad2_)
- /*
- * When free pages are below this point, additional steps are taken
- * when reading the number of free pages to avoid per-cpu counter
- * drift allowing watermarks to be breached
- */
- unsigned long percpu_drift_mark;
- #if defined CONFIG_COMPACTION || defined CONFIG_CMA
- /* pfn where compaction free scanner should start */
- unsigned long compact_cached_free_pfn;
- /* pfn where compaction migration scanner should start */
- unsigned long compact_cached_migrate_pfn[ASYNC_AND_SYNC];
- unsigned long compact_init_migrate_pfn;
- unsigned long compact_init_free_pfn;
- #endif
- #ifdef CONFIG_COMPACTION
- /*
- * On compaction failure, 1<<compact_defer_shift compactions
- * are skipped before trying again. The number attempted since
- * last failure is tracked with compact_considered.
- * compact_order_failed is the minimum compaction failed order.
- */
- unsigned int compact_considered;
- unsigned int compact_defer_shift;
- int compact_order_failed;
- #endif
- #if defined CONFIG_COMPACTION || defined CONFIG_CMA
- /* Set to true when the PG_migrate_skip bits should be cleared */
- bool compact_blockskip_flush;
- #endif
- bool contiguous;
- ZONE_PADDING(_pad3_)
- /* Zone statistics */
- atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
- atomic_long_t vm_numa_stat[NR_VM_NUMA_STAT_ITEMS];
- ANDROID_KABI_RESERVE(1);
- ANDROID_KABI_RESERVE(2);
- ANDROID_KABI_RESERVE(3);
- ANDROID_KABI_RESERVE(4);
- } ____cacheline_internodealigned_in_smp;
- enum pgdat_flags {
- PGDAT_DIRTY, /* reclaim scanning has recently found
- * many dirty file pages at the tail
- * of the LRU.
- */
- PGDAT_WRITEBACK, /* reclaim scanning has recently found
- * many pages under writeback
- */
- PGDAT_RECLAIM_LOCKED, /* prevents concurrent reclaim */
- };
- enum zone_flags {
- ZONE_BOOSTED_WATERMARK, /* zone recently boosted watermarks.
- * Cleared when kswapd is woken.
- */
- };
- static inline unsigned long zone_managed_pages(struct zone *zone)
- {
- return (unsigned long)atomic_long_read(&zone->managed_pages);
- }
- static inline unsigned long zone_cma_pages(struct zone *zone)
- {
- #ifdef CONFIG_CMA
- return zone->cma_pages;
- #else
- return 0;
- #endif
- }
- static inline unsigned long zone_end_pfn(const struct zone *zone)
- {
- return zone->zone_start_pfn + zone->spanned_pages;
- }
- static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn)
- {
- return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone);
- }
- static inline bool zone_is_initialized(struct zone *zone)
- {
- return zone->initialized;
- }
- static inline bool zone_is_empty(struct zone *zone)
- {
- return zone->spanned_pages == 0;
- }
- /*
- * Return true if [start_pfn, start_pfn + nr_pages) range has a non-empty
- * intersection with the given zone
- */
- static inline bool zone_intersects(struct zone *zone,
- unsigned long start_pfn, unsigned long nr_pages)
- {
- if (zone_is_empty(zone))
- return false;
- if (start_pfn >= zone_end_pfn(zone) ||
- start_pfn + nr_pages <= zone->zone_start_pfn)
- return false;
- return true;
- }
- /*
- * The "priority" of VM scanning is how much of the queues we will scan in one
- * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
- * queues ("queue_length >> 12") during an aging round.
- */
- #define DEF_PRIORITY 12
- /* Maximum number of zones on a zonelist */
- #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
- enum {
- ZONELIST_FALLBACK, /* zonelist with fallback */
- #ifdef CONFIG_NUMA
- /*
- * The NUMA zonelists are doubled because we need zonelists that
- * restrict the allocations to a single node for __GFP_THISNODE.
- */
- ZONELIST_NOFALLBACK, /* zonelist without fallback (__GFP_THISNODE) */
- #endif
- MAX_ZONELISTS
- };
- /*
- * This struct contains information about a zone in a zonelist. It is stored
- * here to avoid dereferences into large structures and lookups of tables
- */
- struct zoneref {
- struct zone *zone; /* Pointer to actual zone */
- int zone_idx; /* zone_idx(zoneref->zone) */
- };
- /*
- * One allocation request operates on a zonelist. A zonelist
- * is a list of zones, the first one is the 'goal' of the
- * allocation, the other zones are fallback zones, in decreasing
- * priority.
- *
- * To speed the reading of the zonelist, the zonerefs contain the zone index
- * of the entry being read. Helper functions to access information given
- * a struct zoneref are
- *
- * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
- * zonelist_zone_idx() - Return the index of the zone for an entry
- * zonelist_node_idx() - Return the index of the node for an entry
- */
- struct zonelist {
- struct zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1];
- };
- #ifndef CONFIG_DISCONTIGMEM
- /* The array of struct pages - for discontigmem use pgdat->lmem_map */
- extern struct page *mem_map;
- #endif
- #ifdef CONFIG_TRANSPARENT_HUGEPAGE
- struct deferred_split {
- spinlock_t split_queue_lock;
- struct list_head split_queue;
- unsigned long split_queue_len;
- };
- #endif
- /*
- * On NUMA machines, each NUMA node would have a pg_data_t to describe
- * it's memory layout. On UMA machines there is a single pglist_data which
- * describes the whole memory.
- *
- * Memory statistics and page replacement data structures are maintained on a
- * per-zone basis.
- */
- typedef struct pglist_data {
- /*
- * node_zones contains just the zones for THIS node. Not all of the
- * zones may be populated, but it is the full list. It is referenced by
- * this node's node_zonelists as well as other node's node_zonelists.
- */
- struct zone node_zones[MAX_NR_ZONES];
- /*
- * node_zonelists contains references to all zones in all nodes.
- * Generally the first zones will be references to this node's
- * node_zones.
- */
- struct zonelist node_zonelists[MAX_ZONELISTS];
- int nr_zones; /* number of populated zones in this node */
- #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
- struct page *node_mem_map;
- #ifdef CONFIG_PAGE_EXTENSION
- struct page_ext *node_page_ext;
- #endif
- #endif
- #if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
- /*
- * Must be held any time you expect node_start_pfn,
- * node_present_pages, node_spanned_pages or nr_zones to stay constant.
- * Also synchronizes pgdat->first_deferred_pfn during deferred page
- * init.
- *
- * pgdat_resize_lock() and pgdat_resize_unlock() are provided to
- * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG
- * or CONFIG_DEFERRED_STRUCT_PAGE_INIT.
- *
- * Nests above zone->lock and zone->span_seqlock
- */
- spinlock_t node_size_lock;
- #endif
- unsigned long node_start_pfn;
- unsigned long node_present_pages; /* total number of physical pages */
- unsigned long node_spanned_pages; /* total size of physical page
- range, including holes */
- int node_id;
- wait_queue_head_t kswapd_wait;
- wait_queue_head_t pfmemalloc_wait;
- struct task_struct *kswapd; /* Protected by
- mem_hotplug_begin/end() */
- struct task_struct *mkswapd[MAX_KSWAPD_THREADS];
- int kswapd_order;
- enum zone_type kswapd_highest_zoneidx;
- int kswapd_failures; /* Number of 'reclaimed == 0' runs */
- ANDROID_OEM_DATA(1);
- #ifdef CONFIG_COMPACTION
- int kcompactd_max_order;
- enum zone_type kcompactd_highest_zoneidx;
- wait_queue_head_t kcompactd_wait;
- struct task_struct *kcompactd;
- bool proactive_compact_trigger;
- #endif
- /*
- * This is a per-node reserve of pages that are not available
- * to userspace allocations.
- */
- unsigned long totalreserve_pages;
- #ifdef CONFIG_NUMA
- /*
- * node reclaim becomes active if more unmapped pages exist.
- */
- unsigned long min_unmapped_pages;
- unsigned long min_slab_pages;
- #endif /* CONFIG_NUMA */
- /* Write-intensive fields used by page reclaim */
- ZONE_PADDING(_pad1_)
- spinlock_t lru_lock;
- #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
- /*
- * If memory initialisation on large machines is deferred then this
- * is the first PFN that needs to be initialised.
- */
- unsigned long first_deferred_pfn;
- #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
- #ifdef CONFIG_TRANSPARENT_HUGEPAGE
- struct deferred_split deferred_split_queue;
- #endif
- /* Fields commonly accessed by the page reclaim scanner */
- /*
- * NOTE: THIS IS UNUSED IF MEMCG IS ENABLED.
- *
- * Use mem_cgroup_lruvec() to look up lruvecs.
- */
- struct lruvec __lruvec;
- unsigned long flags;
- ZONE_PADDING(_pad2_)
- /* Per-node vmstats */
- struct per_cpu_nodestat __percpu *per_cpu_nodestats;
- atomic_long_t vm_stat[NR_VM_NODE_STAT_ITEMS];
- } pg_data_t;
- #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
- #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
- #ifdef CONFIG_FLAT_NODE_MEM_MAP
- #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
- #else
- #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
- #endif
- #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
- #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
- #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))
- static inline unsigned long pgdat_end_pfn(pg_data_t *pgdat)
- {
- return pgdat->node_start_pfn + pgdat->node_spanned_pages;
- }
- static inline bool pgdat_is_empty(pg_data_t *pgdat)
- {
- return !pgdat->node_start_pfn && !pgdat->node_spanned_pages;
- }
- #include <linux/memory_hotplug.h>
- void build_all_zonelists(pg_data_t *pgdat);
- void wakeup_kswapd(struct zone *zone, gfp_t gfp_mask, int order,
- enum zone_type highest_zoneidx);
- bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
- int highest_zoneidx, unsigned int alloc_flags,
- long free_pages);
- bool zone_watermark_ok(struct zone *z, unsigned int order,
- unsigned long mark, int highest_zoneidx,
- unsigned int alloc_flags);
- bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
- unsigned long mark, int highest_zoneidx);
- /*
- * Memory initialization context, use to differentiate memory added by
- * the platform statically or via memory hotplug interface.
- */
- enum meminit_context {
- MEMINIT_EARLY,
- MEMINIT_HOTPLUG,
- };
- extern void init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
- unsigned long size);
- extern void lruvec_init(struct lruvec *lruvec);
- static inline struct pglist_data *lruvec_pgdat(struct lruvec *lruvec)
- {
- #ifdef CONFIG_MEMCG
- return lruvec->pgdat;
- #else
- return container_of(lruvec, struct pglist_data, __lruvec);
- #endif
- }
- extern unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru, int zone_idx);
- #ifdef CONFIG_HAVE_MEMORYLESS_NODES
- int local_memory_node(int node_id);
- #else
- static inline int local_memory_node(int node_id) { return node_id; };
- #endif
- /*
- * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
- */
- #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
- /*
- * Returns true if a zone has pages managed by the buddy allocator.
- * All the reclaim decisions have to use this function rather than
- * populated_zone(). If the whole zone is reserved then we can easily
- * end up with populated_zone() && !managed_zone().
- */
- static inline bool managed_zone(struct zone *zone)
- {
- return zone_managed_pages(zone);
- }
- /* Returns true if a zone has memory */
- static inline bool populated_zone(struct zone *zone)
- {
- return zone->present_pages;
- }
- #ifdef CONFIG_NEED_MULTIPLE_NODES
- static inline int zone_to_nid(struct zone *zone)
- {
- return zone->node;
- }
- static inline void zone_set_nid(struct zone *zone, int nid)
- {
- zone->node = nid;
- }
- #else
- static inline int zone_to_nid(struct zone *zone)
- {
- return 0;
- }
- static inline void zone_set_nid(struct zone *zone, int nid) {}
- #endif
- extern int movable_zone;
- #ifdef CONFIG_HIGHMEM
- static inline int zone_movable_is_highmem(void)
- {
- #ifdef CONFIG_NEED_MULTIPLE_NODES
- return movable_zone == ZONE_HIGHMEM;
- #else
- return (ZONE_MOVABLE - 1) == ZONE_HIGHMEM;
- #endif
- }
- #endif
- static inline int is_highmem_idx(enum zone_type idx)
- {
- #ifdef CONFIG_HIGHMEM
- return (idx == ZONE_HIGHMEM ||
- (idx == ZONE_MOVABLE && zone_movable_is_highmem()));
- #else
- return 0;
- #endif
- }
- #ifdef CONFIG_ZONE_DMA
- bool has_managed_dma(void);
- #else
- static inline bool has_managed_dma(void)
- {
- return false;
- }
- #endif
- /**
- * is_highmem - helper function to quickly check if a struct zone is a
- * highmem zone or not. This is an attempt to keep references
- * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
- * @zone - pointer to struct zone variable
- */
- static inline int is_highmem(struct zone *zone)
- {
- #ifdef CONFIG_HIGHMEM
- return is_highmem_idx(zone_idx(zone));
- #else
- return 0;
- #endif
- }
- /* These two functions are used to setup the per zone pages min values */
- struct ctl_table;
- int min_free_kbytes_sysctl_handler(struct ctl_table *, int, void *, size_t *,
- loff_t *);
- int watermark_scale_factor_sysctl_handler(struct ctl_table *, int, void *,
- size_t *, loff_t *);
- extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES];
- int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int, void *,
- size_t *, loff_t *);
- int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int,
- void *, size_t *, loff_t *);
- int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
- void *, size_t *, loff_t *);
- int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
- void *, size_t *, loff_t *);
- int numa_zonelist_order_handler(struct ctl_table *, int,
- void *, size_t *, loff_t *);
- extern int percpu_pagelist_fraction;
- extern char numa_zonelist_order[];
- #define NUMA_ZONELIST_ORDER_LEN 16
- #ifndef CONFIG_NEED_MULTIPLE_NODES
- extern struct pglist_data contig_page_data;
- #define NODE_DATA(nid) (&contig_page_data)
- #define NODE_MEM_MAP(nid) mem_map
- #else /* CONFIG_NEED_MULTIPLE_NODES */
- #include <asm/mmzone.h>
- #endif /* !CONFIG_NEED_MULTIPLE_NODES */
- extern struct pglist_data *first_online_pgdat(void);
- extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
- extern struct zone *next_zone(struct zone *zone);
- extern int isolate_anon_lru_page(struct page *page);
- /**
- * for_each_online_pgdat - helper macro to iterate over all online nodes
- * @pgdat - pointer to a pg_data_t variable
- */
- #define for_each_online_pgdat(pgdat) \
- for (pgdat = first_online_pgdat(); \
- pgdat; \
- pgdat = next_online_pgdat(pgdat))
- /**
- * for_each_zone - helper macro to iterate over all memory zones
- * @zone - pointer to struct zone variable
- *
- * The user only needs to declare the zone variable, for_each_zone
- * fills it in.
- */
- #define for_each_zone(zone) \
- for (zone = (first_online_pgdat())->node_zones; \
- zone; \
- zone = next_zone(zone))
- #define for_each_populated_zone(zone) \
- for (zone = (first_online_pgdat())->node_zones; \
- zone; \
- zone = next_zone(zone)) \
- if (!populated_zone(zone)) \
- ; /* do nothing */ \
- else
- static inline struct zone *zonelist_zone(struct zoneref *zoneref)
- {
- return zoneref->zone;
- }
- static inline int zonelist_zone_idx(struct zoneref *zoneref)
- {
- return zoneref->zone_idx;
- }
- static inline int zonelist_node_idx(struct zoneref *zoneref)
- {
- return zone_to_nid(zoneref->zone);
- }
- struct zoneref *__next_zones_zonelist(struct zoneref *z,
- enum zone_type highest_zoneidx,
- nodemask_t *nodes);
- /**
- * 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
- * @z - The cursor used as a starting point for the search
- * @highest_zoneidx - The zone index of the highest zone to return
- * @nodes - An optional nodemask to filter the zonelist with
- *
- * This function returns the next zone at or below a given zone index that is
- * within the allowed nodemask using a cursor as the starting point for the
- * search. The zoneref returned is a cursor that represents the current zone
- * being examined. It should be advanced by one before calling
- * next_zones_zonelist again.
- */
- static __always_inline struct zoneref *next_zones_zonelist(struct zoneref *z,
- enum zone_type highest_zoneidx,
- nodemask_t *nodes)
- {
- if (likely(!nodes && zonelist_zone_idx(z) <= highest_zoneidx))
- return z;
- return __next_zones_zonelist(z, highest_zoneidx, nodes);
- }
- /**
- * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
- * @zonelist - The zonelist to search for a suitable zone
- * @highest_zoneidx - The zone index of the highest zone to return
- * @nodes - An optional nodemask to filter the zonelist with
- * @return - Zoneref pointer for the first suitable zone found (see below)
- *
- * This function returns the first zone at or below a given zone index that is
- * within the allowed nodemask. The zoneref returned is a cursor that can be
- * used to iterate the zonelist with next_zones_zonelist by advancing it by
- * one before calling.
- *
- * When no eligible zone is found, zoneref->zone is NULL (zoneref itself is
- * never NULL). This may happen either genuinely, or due to concurrent nodemask
- * update due to cpuset modification.
- */
- static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
- enum zone_type highest_zoneidx,
- nodemask_t *nodes)
- {
- return next_zones_zonelist(zonelist->_zonerefs,
- highest_zoneidx, nodes);
- }
- /**
- * 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
- * @zone - The current zone in the iterator
- * @z - The current pointer within zonelist->_zonerefs being iterated
- * @zlist - The zonelist being iterated
- * @highidx - The zone index of the highest zone to return
- * @nodemask - Nodemask allowed by the allocator
- *
- * This iterator iterates though all zones at or below a given zone index and
- * within a given nodemask
- */
- #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
- for (z = first_zones_zonelist(zlist, highidx, nodemask), zone = zonelist_zone(z); \
- zone; \
- z = next_zones_zonelist(++z, highidx, nodemask), \
- zone = zonelist_zone(z))
- #define for_next_zone_zonelist_nodemask(zone, z, highidx, nodemask) \
- for (zone = z->zone; \
- zone; \
- z = next_zones_zonelist(++z, highidx, nodemask), \
- zone = zonelist_zone(z))
- /**
- * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
- * @zone - The current zone in the iterator
- * @z - The current pointer within zonelist->zones being iterated
- * @zlist - The zonelist being iterated
- * @highidx - The zone index of the highest zone to return
- *
- * This iterator iterates though all zones at or below a given zone index.
- */
- #define for_each_zone_zonelist(zone, z, zlist, highidx) \
- for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
- #ifdef CONFIG_SPARSEMEM
- #include <asm/sparsemem.h>
- #endif
- #ifdef CONFIG_FLATMEM
- #define pfn_to_nid(pfn) (0)
- #endif
- #ifdef CONFIG_SPARSEMEM
- /*
- * SECTION_SHIFT #bits space required to store a section #
- *
- * PA_SECTION_SHIFT physical address to/from section number
- * PFN_SECTION_SHIFT pfn to/from section number
- */
- #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
- #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
- #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
- #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
- #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
- #define SECTION_BLOCKFLAGS_BITS \
- ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
- #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
- #error Allocator MAX_ORDER exceeds SECTION_SIZE
- #endif
- static inline unsigned long pfn_to_section_nr(unsigned long pfn)
- {
- return pfn >> PFN_SECTION_SHIFT;
- }
- static inline unsigned long section_nr_to_pfn(unsigned long sec)
- {
- return sec << PFN_SECTION_SHIFT;
- }
- #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
- #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
- #define SUBSECTION_SHIFT 21
- #define SUBSECTION_SIZE (1UL << SUBSECTION_SHIFT)
- #define PFN_SUBSECTION_SHIFT (SUBSECTION_SHIFT - PAGE_SHIFT)
- #define PAGES_PER_SUBSECTION (1UL << PFN_SUBSECTION_SHIFT)
- #define PAGE_SUBSECTION_MASK (~(PAGES_PER_SUBSECTION-1))
- #if SUBSECTION_SHIFT > SECTION_SIZE_BITS
- #error Subsection size exceeds section size
- #else
- #define SUBSECTIONS_PER_SECTION (1UL << (SECTION_SIZE_BITS - SUBSECTION_SHIFT))
- #endif
- #define SUBSECTION_ALIGN_UP(pfn) ALIGN((pfn), PAGES_PER_SUBSECTION)
- #define SUBSECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SUBSECTION_MASK)
- struct mem_section_usage {
- #ifdef CONFIG_SPARSEMEM_VMEMMAP
- DECLARE_BITMAP(subsection_map, SUBSECTIONS_PER_SECTION);
- #endif
- /* See declaration of similar field in struct zone */
- unsigned long pageblock_flags[0];
- };
- void subsection_map_init(unsigned long pfn, unsigned long nr_pages);
- struct page;
- struct page_ext;
- struct mem_section {
- /*
- * This is, logically, a pointer to an array of struct
- * pages. However, it is stored with some other magic.
- * (see sparse.c::sparse_init_one_section())
- *
- * Additionally during early boot we encode node id of
- * the location of the section here to guide allocation.
- * (see sparse.c::memory_present())
- *
- * Making it a UL at least makes someone do a cast
- * before using it wrong.
- */
- unsigned long section_mem_map;
- struct mem_section_usage *usage;
- #ifdef CONFIG_PAGE_EXTENSION
- /*
- * If SPARSEMEM, pgdat doesn't have page_ext pointer. We use
- * section. (see page_ext.h about this.)
- */
- struct page_ext *page_ext;
- unsigned long pad;
- #endif
- /*
- * WARNING: mem_section must be a power-of-2 in size for the
- * calculation and use of SECTION_ROOT_MASK to make sense.
- */
- };
- #ifdef CONFIG_SPARSEMEM_EXTREME
- #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
- #else
- #define SECTIONS_PER_ROOT 1
- #endif
- #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
- #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
- #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
- #ifdef CONFIG_SPARSEMEM_EXTREME
- extern struct mem_section **mem_section;
- #else
- extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
- #endif
- static inline unsigned long *section_to_usemap(struct mem_section *ms)
- {
- return ms->usage->pageblock_flags;
- }
- static inline struct mem_section *__nr_to_section(unsigned long nr)
- {
- unsigned long root = SECTION_NR_TO_ROOT(nr);
- if (unlikely(root >= NR_SECTION_ROOTS))
- return NULL;
- #ifdef CONFIG_SPARSEMEM_EXTREME
- if (!mem_section || !mem_section[root])
- return NULL;
- #endif
- return &mem_section[root][nr & SECTION_ROOT_MASK];
- }
- extern unsigned long __section_nr(struct mem_section *ms);
- extern size_t mem_section_usage_size(void);
- /*
- * We use the lower bits of the mem_map pointer to store
- * a little bit of information. The pointer is calculated
- * as mem_map - section_nr_to_pfn(pnum). The result is
- * aligned to the minimum alignment of the two values:
- * 1. All mem_map arrays are page-aligned.
- * 2. section_nr_to_pfn() always clears PFN_SECTION_SHIFT
- * lowest bits. PFN_SECTION_SHIFT is arch-specific
- * (equal SECTION_SIZE_BITS - PAGE_SHIFT), and the
- * worst combination is powerpc with 256k pages,
- * which results in PFN_SECTION_SHIFT equal 6.
- * To sum it up, at least 6 bits are available.
- */
- #define SECTION_MARKED_PRESENT (1UL<<0)
- #define SECTION_HAS_MEM_MAP (1UL<<1)
- #define SECTION_IS_ONLINE (1UL<<2)
- #define SECTION_IS_EARLY (1UL<<3)
- #define SECTION_MAP_LAST_BIT (1UL<<4)
- #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
- #define SECTION_NID_SHIFT 3
- static inline struct page *__section_mem_map_addr(struct mem_section *section)
- {
- unsigned long map = section->section_mem_map;
- map &= SECTION_MAP_MASK;
- return (struct page *)map;
- }
- static inline int present_section(struct mem_section *section)
- {
- return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
- }
- static inline int present_section_nr(unsigned long nr)
- {
- return present_section(__nr_to_section(nr));
- }
- static inline int valid_section(struct mem_section *section)
- {
- return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
- }
- static inline int early_section(struct mem_section *section)
- {
- return (section && (section->section_mem_map & SECTION_IS_EARLY));
- }
- static inline int valid_section_nr(unsigned long nr)
- {
- return valid_section(__nr_to_section(nr));
- }
- static inline int online_section(struct mem_section *section)
- {
- return (section && (section->section_mem_map & SECTION_IS_ONLINE));
- }
- static inline int online_section_nr(unsigned long nr)
- {
- return online_section(__nr_to_section(nr));
- }
- #ifdef CONFIG_MEMORY_HOTPLUG
- void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn);
- #ifdef CONFIG_MEMORY_HOTREMOVE
- void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn);
- #endif
- #endif
- static inline struct mem_section *__pfn_to_section(unsigned long pfn)
- {
- return __nr_to_section(pfn_to_section_nr(pfn));
- }
- extern unsigned long __highest_present_section_nr;
- static inline int subsection_map_index(unsigned long pfn)
- {
- return (pfn & ~(PAGE_SECTION_MASK)) / PAGES_PER_SUBSECTION;
- }
- #ifdef CONFIG_SPARSEMEM_VMEMMAP
- static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn)
- {
- int idx = subsection_map_index(pfn);
- return test_bit(idx, ms->usage->subsection_map);
- }
- #else
- static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn)
- {
- return 1;
- }
- #endif
- #ifndef CONFIG_HAVE_ARCH_PFN_VALID
- static inline int pfn_valid(unsigned long pfn)
- {
- struct mem_section *ms;
- if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
- return 0;
- ms = __nr_to_section(pfn_to_section_nr(pfn));
- if (!valid_section(ms))
- return 0;
- /*
- * Traditionally early sections always returned pfn_valid() for
- * the entire section-sized span.
- */
- return early_section(ms) || pfn_section_valid(ms, pfn);
- }
- #endif
- static inline int pfn_in_present_section(unsigned long pfn)
- {
- if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
- return 0;
- return present_section(__nr_to_section(pfn_to_section_nr(pfn)));
- }
- static inline unsigned long next_present_section_nr(unsigned long section_nr)
- {
- while (++section_nr <= __highest_present_section_nr) {
- if (present_section_nr(section_nr))
- return section_nr;
- }
- return -1;
- }
- /*
- * These are _only_ used during initialisation, therefore they
- * can use __initdata ... They could have names to indicate
- * this restriction.
- */
- #ifdef CONFIG_NUMA
- #define pfn_to_nid(pfn) \
- ({ \
- unsigned long __pfn_to_nid_pfn = (pfn); \
- page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
- })
- #else
- #define pfn_to_nid(pfn) (0)
- #endif
- void sparse_init(void);
- #else
- #define sparse_init() do {} while (0)
- #define sparse_index_init(_sec, _nid) do {} while (0)
- #define pfn_in_present_section pfn_valid
- #define subsection_map_init(_pfn, _nr_pages) do {} while (0)
- #endif /* CONFIG_SPARSEMEM */
- /*
- * During memory init memblocks map pfns to nids. The search is expensive and
- * this caches recent lookups. The implementation of __early_pfn_to_nid
- * may treat start/end as pfns or sections.
- */
- struct mminit_pfnnid_cache {
- unsigned long last_start;
- unsigned long last_end;
- int last_nid;
- };
- /*
- * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
- * need to check pfn validity within that MAX_ORDER_NR_PAGES block.
- * pfn_valid_within() should be used in this case; we optimise this away
- * when we have no holes within a MAX_ORDER_NR_PAGES block.
- */
- #ifdef CONFIG_HOLES_IN_ZONE
- #define pfn_valid_within(pfn) pfn_valid(pfn)
- #else
- #define pfn_valid_within(pfn) (1)
- #endif
- #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
- /*
- * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
- * associated with it or not. This means that a struct page exists for this
- * pfn. The caller cannot assume the page is fully initialized in general.
- * Hotplugable pages might not have been onlined yet. pfn_to_online_page()
- * will ensure the struct page is fully online and initialized. Special pages
- * (e.g. ZONE_DEVICE) are never onlined and should be treated accordingly.
- *
- * In FLATMEM, it is expected that holes always have valid memmap as long as
- * there is valid PFNs either side of the hole. In SPARSEMEM, it is assumed
- * that a valid section has a memmap for the entire section.
- *
- * However, an ARM, and maybe other embedded architectures in the future
- * free memmap backing holes to save memory on the assumption the memmap is
- * never used. The page_zone linkages are then broken even though pfn_valid()
- * returns true. A walker of the full memmap must then do this additional
- * check to ensure the memmap they are looking at is sane by making sure
- * the zone and PFN linkages are still valid. This is expensive, but walkers
- * of the full memmap are extremely rare.
- */
- bool memmap_valid_within(unsigned long pfn,
- struct page *page, struct zone *zone);
- #else
- static inline bool memmap_valid_within(unsigned long pfn,
- struct page *page, struct zone *zone)
- {
- return true;
- }
- #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
- #endif /* !__GENERATING_BOUNDS.H */
- #endif /* !__ASSEMBLY__ */
- #endif /* _LINUX_MMZONE_H */
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