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Diffstat (limited to 'include/linux/mmzone.h')
| -rw-r--r-- | include/linux/mmzone.h | 2067 |
1 files changed, 2067 insertions, 0 deletions
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h new file mode 100644 index 000000000..f43a1cdcc --- /dev/null +++ b/include/linux/mmzone.h @@ -0,0 +1,2067 @@ +/* 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/list_nulls.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/local_lock.h> +#include <asm/page.h> + +/* Free memory management - zoned buddy allocator. */ +#ifndef CONFIG_ARCH_FORCE_MAX_ORDER +#define MAX_ORDER 10 +#else +#define MAX_ORDER CONFIG_ARCH_FORCE_MAX_ORDER +#endif +#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER) + +#define IS_MAX_ORDER_ALIGNED(pfn) IS_ALIGNED(pfn, MAX_ORDER_NR_PAGES) + +/* + * 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 + +enum migratetype { + MIGRATE_UNMOVABLE, + MIGRATE_MOVABLE, + MIGRATE_RECLAIMABLE, + MIGRATE_PCPTYPES, /* the number of types on the pcp lists */ + MIGRATE_HIGHATOMIC = MIGRATE_PCPTYPES, +#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. + */ + MIGRATE_CMA, +#endif +#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) +#else +# define is_migrate_cma(migratetype) false +# define is_migrate_cma_page(_page) false +#endif + +static inline bool is_migrate_movable(int mt) +{ + return is_migrate_cma(mt) || mt == MIGRATE_MOVABLE; +} + +/* + * Check whether a migratetype can be merged with another migratetype. + * + * It is only mergeable when it can fall back to other migratetypes for + * allocation. See fallbacks[MIGRATE_TYPES][3] in page_alloc.c. + */ +static inline bool migratetype_is_mergeable(int mt) +{ + return mt < MIGRATE_PCPTYPES; +} + +#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) + +#define folio_migratetype(folio) \ + get_pfnblock_flags_mask(&folio->page, folio_pfn(folio), \ + MIGRATETYPE_MASK) +struct free_area { + struct list_head free_list[MIGRATE_TYPES]; + unsigned long nr_free; +}; + +struct pglist_data; + +#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_EVENT_ITEMS +}; +#else +#define NR_VM_NUMA_EVENT_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 */ + /* Second 128 byte cacheline */ + NR_BOUNCE, +#if IS_ENABLED(CONFIG_ZSMALLOC) + NR_ZSPAGES, /* allocated in zsmalloc */ +#endif + NR_FREE_CMA_PAGES, +#ifdef CONFIG_UNACCEPTED_MEMORY + NR_UNACCEPTED, +#endif + 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_THROTTLED_WRITTEN, /* NR_WRITTEN while reclaim throttled */ + 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_PAGETABLE, /* used for pagetables */ + NR_SECONDARY_PAGETABLE, /* secondary pagetables, e.g. KVM pagetables */ +#ifdef CONFIG_SWAP + NR_SWAPCACHE, +#endif +#ifdef CONFIG_NUMA_BALANCING + PGPROMOTE_SUCCESS, /* promote successfully */ + PGPROMOTE_CANDIDATE, /* candidate pages to promote */ +#endif + NR_VM_NODE_STAT_ITEMS +}; + +/* + * Returns true if the item should be printed in THPs (/proc/vmstat + * currently prints number of anon, file and shmem THPs. But the item + * is charged in pages). + */ +static __always_inline bool vmstat_item_print_in_thp(enum node_stat_item item) +{ + if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) + return false; + + return item == NR_ANON_THPS || + item == NR_FILE_THPS || + item == NR_SHMEM_THPS || + item == NR_SHMEM_PMDMAPPED || + item == NR_FILE_PMDMAPPED; +} + +/* + * 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 +}; + +enum vmscan_throttle_state { + VMSCAN_THROTTLE_WRITEBACK, + VMSCAN_THROTTLE_ISOLATED, + VMSCAN_THROTTLE_NOPROGRESS, + VMSCAN_THROTTLE_CONGESTED, + NR_VMSCAN_THROTTLE, +}; + +#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 WORKINGSET_ANON 0 +#define WORKINGSET_FILE 1 +#define ANON_AND_FILE 2 + +enum lruvec_flags { + /* + * An lruvec has many dirty pages backed by a congested BDI: + * 1. LRUVEC_CGROUP_CONGESTED is set by cgroup-level reclaim. + * It can be cleared by cgroup reclaim or kswapd. + * 2. LRUVEC_NODE_CONGESTED is set by kswapd node-level reclaim. + * It can only be cleared by kswapd. + * + * Essentially, kswapd can unthrottle an lruvec throttled by cgroup + * reclaim, but not vice versa. This only applies to the root cgroup. + * The goal is to prevent cgroup reclaim on the root cgroup (e.g. + * memory.reclaim) to unthrottle an unbalanced node (that was throttled + * by kswapd). + */ + LRUVEC_CGROUP_CONGESTED, + LRUVEC_NODE_CONGESTED, +}; + +#endif /* !__GENERATING_BOUNDS_H */ + +/* + * Evictable pages are divided into multiple generations. The youngest and the + * oldest generation numbers, max_seq and min_seq, are monotonically increasing. + * They form a sliding window of a variable size [MIN_NR_GENS, MAX_NR_GENS]. An + * offset within MAX_NR_GENS, i.e., gen, indexes the LRU list of the + * corresponding generation. The gen counter in folio->flags stores gen+1 while + * a page is on one of lrugen->folios[]. Otherwise it stores 0. + * + * A page is added to the youngest generation on faulting. The aging needs to + * check the accessed bit at least twice before handing this page over to the + * eviction. The first check takes care of the accessed bit set on the initial + * fault; the second check makes sure this page hasn't been used since then. + * This process, AKA second chance, requires a minimum of two generations, + * hence MIN_NR_GENS. And to maintain ABI compatibility with the active/inactive + * LRU, e.g., /proc/vmstat, these two generations are considered active; the + * rest of generations, if they exist, are considered inactive. See + * lru_gen_is_active(). + * + * PG_active is always cleared while a page is on one of lrugen->folios[] so + * that the aging needs not to worry about it. And it's set again when a page + * considered active is isolated for non-reclaiming purposes, e.g., migration. + * See lru_gen_add_folio() and lru_gen_del_folio(). + * + * MAX_NR_GENS is set to 4 so that the multi-gen LRU can support twice the + * number of categories of the active/inactive LRU when keeping track of + * accesses through page tables. This requires order_base_2(MAX_NR_GENS+1) bits + * in folio->flags. + */ +#define MIN_NR_GENS 2U +#define MAX_NR_GENS 4U + +/* + * Each generation is divided into multiple tiers. A page accessed N times + * through file descriptors is in tier order_base_2(N). A page in the first tier + * (N=0,1) is marked by PG_referenced unless it was faulted in through page + * tables or read ahead. A page in any other tier (N>1) is marked by + * PG_referenced and PG_workingset. This implies a minimum of two tiers is + * supported without using additional bits in folio->flags. + * + * In contrast to moving across generations which requires the LRU lock, moving + * across tiers only involves atomic operations on folio->flags and therefore + * has a negligible cost in the buffered access path. In the eviction path, + * comparisons of refaulted/(evicted+protected) from the first tier and the + * rest infer whether pages accessed multiple times through file descriptors + * are statistically hot and thus worth protecting. + * + * MAX_NR_TIERS is set to 4 so that the multi-gen LRU can support twice the + * number of categories of the active/inactive LRU when keeping track of + * accesses through file descriptors. This uses MAX_NR_TIERS-2 spare bits in + * folio->flags. + */ +#define MAX_NR_TIERS 4U + +#ifndef __GENERATING_BOUNDS_H + +struct lruvec; +struct page_vma_mapped_walk; + +#define LRU_GEN_MASK ((BIT(LRU_GEN_WIDTH) - 1) << LRU_GEN_PGOFF) +#define LRU_REFS_MASK ((BIT(LRU_REFS_WIDTH) - 1) << LRU_REFS_PGOFF) + +#ifdef CONFIG_LRU_GEN + +enum { + LRU_GEN_ANON, + LRU_GEN_FILE, +}; + +enum { + LRU_GEN_CORE, + LRU_GEN_MM_WALK, + LRU_GEN_NONLEAF_YOUNG, + NR_LRU_GEN_CAPS +}; + +#define MIN_LRU_BATCH BITS_PER_LONG +#define MAX_LRU_BATCH (MIN_LRU_BATCH * 64) + +/* whether to keep historical stats from evicted generations */ +#ifdef CONFIG_LRU_GEN_STATS +#define NR_HIST_GENS MAX_NR_GENS +#else +#define NR_HIST_GENS 1U +#endif + +/* + * The youngest generation number is stored in max_seq for both anon and file + * types as they are aged on an equal footing. The oldest generation numbers are + * stored in min_seq[] separately for anon and file types as clean file pages + * can be evicted regardless of swap constraints. + * + * Normally anon and file min_seq are in sync. But if swapping is constrained, + * e.g., out of swap space, file min_seq is allowed to advance and leave anon + * min_seq behind. + * + * The number of pages in each generation is eventually consistent and therefore + * can be transiently negative when reset_batch_size() is pending. + */ +struct lru_gen_folio { + /* the aging increments the youngest generation number */ + unsigned long max_seq; + /* the eviction increments the oldest generation numbers */ + unsigned long min_seq[ANON_AND_FILE]; + /* the birth time of each generation in jiffies */ + unsigned long timestamps[MAX_NR_GENS]; + /* the multi-gen LRU lists, lazily sorted on eviction */ + struct list_head folios[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; + /* the multi-gen LRU sizes, eventually consistent */ + long nr_pages[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; + /* the exponential moving average of refaulted */ + unsigned long avg_refaulted[ANON_AND_FILE][MAX_NR_TIERS]; + /* the exponential moving average of evicted+protected */ + unsigned long avg_total[ANON_AND_FILE][MAX_NR_TIERS]; + /* the first tier doesn't need protection, hence the minus one */ + unsigned long protected[NR_HIST_GENS][ANON_AND_FILE][MAX_NR_TIERS - 1]; + /* can be modified without holding the LRU lock */ + atomic_long_t evicted[NR_HIST_GENS][ANON_AND_FILE][MAX_NR_TIERS]; + atomic_long_t refaulted[NR_HIST_GENS][ANON_AND_FILE][MAX_NR_TIERS]; + /* whether the multi-gen LRU is enabled */ + bool enabled; +#ifdef CONFIG_MEMCG + /* the memcg generation this lru_gen_folio belongs to */ + u8 gen; + /* the list segment this lru_gen_folio belongs to */ + u8 seg; + /* per-node lru_gen_folio list for global reclaim */ + struct hlist_nulls_node list; +#endif +}; + +enum { + MM_LEAF_TOTAL, /* total leaf entries */ + MM_LEAF_OLD, /* old leaf entries */ + MM_LEAF_YOUNG, /* young leaf entries */ + MM_NONLEAF_TOTAL, /* total non-leaf entries */ + MM_NONLEAF_FOUND, /* non-leaf entries found in Bloom filters */ + MM_NONLEAF_ADDED, /* non-leaf entries added to Bloom filters */ + NR_MM_STATS +}; + +/* double-buffering Bloom filters */ +#define NR_BLOOM_FILTERS 2 + +struct lru_gen_mm_state { + /* set to max_seq after each iteration */ + unsigned long seq; + /* where the current iteration continues after */ + struct list_head *head; + /* where the last iteration ended before */ + struct list_head *tail; + /* Bloom filters flip after each iteration */ + unsigned long *filters[NR_BLOOM_FILTERS]; + /* the mm stats for debugging */ + unsigned long stats[NR_HIST_GENS][NR_MM_STATS]; +}; + +struct lru_gen_mm_walk { + /* the lruvec under reclaim */ + struct lruvec *lruvec; + /* unstable max_seq from lru_gen_folio */ + unsigned long max_seq; + /* the next address within an mm to scan */ + unsigned long next_addr; + /* to batch promoted pages */ + int nr_pages[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; + /* to batch the mm stats */ + int mm_stats[NR_MM_STATS]; + /* total batched items */ + int batched; + bool can_swap; + bool force_scan; +}; + +void lru_gen_init_lruvec(struct lruvec *lruvec); +void lru_gen_look_around(struct page_vma_mapped_walk *pvmw); + +#ifdef CONFIG_MEMCG + +/* + * For each node, memcgs are divided into two generations: the old and the + * young. For each generation, memcgs are randomly sharded into multiple bins + * to improve scalability. For each bin, the hlist_nulls is virtually divided + * into three segments: the head, the tail and the default. + * + * An onlining memcg is added to the tail of a random bin in the old generation. + * The eviction starts at the head of a random bin in the old generation. The + * per-node memcg generation counter, whose reminder (mod MEMCG_NR_GENS) indexes + * the old generation, is incremented when all its bins become empty. + * + * There are four operations: + * 1. MEMCG_LRU_HEAD, which moves a memcg to the head of a random bin in its + * current generation (old or young) and updates its "seg" to "head"; + * 2. MEMCG_LRU_TAIL, which moves a memcg to the tail of a random bin in its + * current generation (old or young) and updates its "seg" to "tail"; + * 3. MEMCG_LRU_OLD, which moves a memcg to the head of a random bin in the old + * generation, updates its "gen" to "old" and resets its "seg" to "default"; + * 4. MEMCG_LRU_YOUNG, which moves a memcg to the tail of a random bin in the + * young generation, updates its "gen" to "young" and resets its "seg" to + * "default". + * + * The events that trigger the above operations are: + * 1. Exceeding the soft limit, which triggers MEMCG_LRU_HEAD; + * 2. The first attempt to reclaim a memcg below low, which triggers + * MEMCG_LRU_TAIL; + * 3. The first attempt to reclaim a memcg offlined or below reclaimable size + * threshold, which triggers MEMCG_LRU_TAIL; + * 4. The second attempt to reclaim a memcg offlined or below reclaimable size + * threshold, which triggers MEMCG_LRU_YOUNG; + * 5. Attempting to reclaim a memcg below min, which triggers MEMCG_LRU_YOUNG; + * 6. Finishing the aging on the eviction path, which triggers MEMCG_LRU_YOUNG; + * 7. Offlining a memcg, which triggers MEMCG_LRU_OLD. + * + * Notes: + * 1. Memcg LRU only applies to global reclaim, and the round-robin incrementing + * of their max_seq counters ensures the eventual fairness to all eligible + * memcgs. For memcg reclaim, it still relies on mem_cgroup_iter(). + * 2. There are only two valid generations: old (seq) and young (seq+1). + * MEMCG_NR_GENS is set to three so that when reading the generation counter + * locklessly, a stale value (seq-1) does not wraparound to young. + */ +#define MEMCG_NR_GENS 3 +#define MEMCG_NR_BINS 8 + +struct lru_gen_memcg { + /* the per-node memcg generation counter */ + unsigned long seq; + /* each memcg has one lru_gen_folio per node */ + unsigned long nr_memcgs[MEMCG_NR_GENS]; + /* per-node lru_gen_folio list for global reclaim */ + struct hlist_nulls_head fifo[MEMCG_NR_GENS][MEMCG_NR_BINS]; + /* protects the above */ + spinlock_t lock; +}; + +void lru_gen_init_pgdat(struct pglist_data *pgdat); + +void lru_gen_init_memcg(struct mem_cgroup *memcg); +void lru_gen_exit_memcg(struct mem_cgroup *memcg); +void lru_gen_online_memcg(struct mem_cgroup *memcg); +void lru_gen_offline_memcg(struct mem_cgroup *memcg); +void lru_gen_release_memcg(struct mem_cgroup *memcg); +void lru_gen_soft_reclaim(struct mem_cgroup *memcg, int nid); + +#else /* !CONFIG_MEMCG */ + +#define MEMCG_NR_GENS 1 + +struct lru_gen_memcg { +}; + +static inline void lru_gen_init_pgdat(struct pglist_data *pgdat) +{ +} + +#endif /* CONFIG_MEMCG */ + +#else /* !CONFIG_LRU_GEN */ + +static inline void lru_gen_init_pgdat(struct pglist_data *pgdat) +{ +} + +static inline void lru_gen_init_lruvec(struct lruvec *lruvec) +{ +} + +static inline void lru_gen_look_around(struct page_vma_mapped_walk *pvmw) +{ +} + +#ifdef CONFIG_MEMCG + +static inline void lru_gen_init_memcg(struct mem_cgroup *memcg) +{ +} + +static inline void lru_gen_exit_memcg(struct mem_cgroup *memcg) +{ +} + +static inline void lru_gen_online_memcg(struct mem_cgroup *memcg) +{ +} + +static inline void lru_gen_offline_memcg(struct mem_cgroup *memcg) +{ +} + +static inline void lru_gen_release_memcg(struct mem_cgroup *memcg) +{ +} + +static inline void lru_gen_soft_reclaim(struct mem_cgroup *memcg, int nid) +{ +} + +#endif /* CONFIG_MEMCG */ + +#endif /* CONFIG_LRU_GEN */ + +struct lruvec { + struct list_head lists[NR_LRU_LISTS]; + /* per lruvec lru_lock for memcg */ + spinlock_t lru_lock; + /* + * 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_LRU_GEN + /* evictable pages divided into generations */ + struct lru_gen_folio lrugen; + /* to concurrently iterate lru_gen_mm_list */ + struct lru_gen_mm_state mm_state; +#endif +#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, + WMARK_PROMO, + NR_WMARK +}; + +/* + * One per migratetype for each PAGE_ALLOC_COSTLY_ORDER. One additional list + * for THP which will usually be GFP_MOVABLE. Even if it is another type, + * it should not contribute to serious fragmentation causing THP allocation + * failures. + */ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#define NR_PCP_THP 1 +#else +#define NR_PCP_THP 0 +#endif +#define NR_LOWORDER_PCP_LISTS (MIGRATE_PCPTYPES * (PAGE_ALLOC_COSTLY_ORDER + 1)) +#define NR_PCP_LISTS (NR_LOWORDER_PCP_LISTS + NR_PCP_THP) + +#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 { + spinlock_t lock; /* Protects lists field */ + int count; /* number of pages in the list */ + int high; /* high watermark, emptying needed */ + int batch; /* chunk size for buddy add/remove */ + short free_factor; /* batch scaling factor during free */ +#ifdef CONFIG_NUMA + short expire; /* When 0, remote pagesets are drained */ +#endif + + /* Lists of pages, one per migrate type stored on the pcp-lists */ + struct list_head lists[NR_PCP_LISTS]; +} ____cacheline_aligned_in_smp; + +struct per_cpu_zonestat { +#ifdef CONFIG_SMP + s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS]; + s8 stat_threshold; +#endif +#ifdef CONFIG_NUMA + /* + * Low priority inaccurate counters that are only folded + * on demand. Use a large type to avoid the overhead of + * folding during refresh_cpu_vm_stats. + */ + unsigned long vm_numa_event[NR_VM_NUMA_EVENT_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. Therefore, we do not allow + * pinning long-term pages in ZONE_MOVABLE. When pages are pinned and + * faulted, they come from the right zone right away. However, it is + * still possible that address space already has pages in + * ZONE_MOVABLE at the time when pages are pinned (i.e. user has + * touches that memory before pinning). In such case we migrate them + * to a different zone. When migration fails - pinning fails. + * 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). + * 6. ZERO_PAGE(0), kernelcore/movablecore setups might create + * situations where ZERO_PAGE(0) which is allocated differently + * on different platforms may end up in a movable zone. ZERO_PAGE(0) + * cannot be migrated. + * 7. Memory-hotplug: when using memmap_on_memory and onlining the + * memory to the MOVABLE zone, the vmemmap pages are also placed in + * such zone. Such pages cannot be really moved around as they are + * self-stored in the range, but they are treated as movable when + * the range they describe is about to be offlined. + * + * 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_NUMA + int node; +#endif + struct pglist_data *zone_pgdat; + struct per_cpu_pages __percpu *per_cpu_pageset; + struct per_cpu_zonestat __percpu *per_cpu_zonestats; + /* + * the high and batch values are copied to individual pagesets for + * faster access + */ + int pageset_high; + int pageset_batch; + +#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); + * + * present_early_pages is present pages existing within the zone + * located on memory available since early boot, excluding hotplugged + * memory. + * + * 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/done(). Any reader who can't tolerant drift of + * present_pages should use get_online_mems() to get a stable value. + */ + atomic_long_t managed_pages; + unsigned long spanned_pages; + unsigned long present_pages; +#if defined(CONFIG_MEMORY_HOTPLUG) + unsigned long present_early_pages; +#endif +#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 */ + CACHELINE_PADDING(_pad1_); + + /* free areas of different sizes */ + struct free_area free_area[MAX_ORDER + 1]; + +#ifdef CONFIG_UNACCEPTED_MEMORY + /* Pages to be accepted. All pages on the list are MAX_ORDER */ + struct list_head unaccepted_pages; +#endif + + /* zone flags, see below */ + unsigned long flags; + + /* Primarily protects free_area */ + spinlock_t lock; + + /* Write-intensive fields used by compaction and vmstats. */ + CACHELINE_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; + + CACHELINE_PADDING(_pad3_); + /* Zone statistics */ + atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS]; + atomic_long_t vm_numa_event[NR_VM_NUMA_EVENT_ITEMS]; +} ____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. + */ + ZONE_RECLAIM_ACTIVE, /* kswapd may be scanning the zone. */ +}; + +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; +} + +#ifndef BUILD_VDSO32_64 +/* + * The zone field is never updated after free_area_init_core() + * sets it, so none of the operations on it need to be atomic. + */ + +/* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_CPUPID] | ... | FLAGS | */ +#define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH) +#define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH) +#define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH) +#define LAST_CPUPID_PGOFF (ZONES_PGOFF - LAST_CPUPID_WIDTH) +#define KASAN_TAG_PGOFF (LAST_CPUPID_PGOFF - KASAN_TAG_WIDTH) +#define LRU_GEN_PGOFF (KASAN_TAG_PGOFF - LRU_GEN_WIDTH) +#define LRU_REFS_PGOFF (LRU_GEN_PGOFF - LRU_REFS_WIDTH) + +/* + * Define the bit shifts to access each section. For non-existent + * sections we define the shift as 0; that plus a 0 mask ensures + * the compiler will optimise away reference to them. + */ +#define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0)) +#define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0)) +#define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0)) +#define LAST_CPUPID_PGSHIFT (LAST_CPUPID_PGOFF * (LAST_CPUPID_WIDTH != 0)) +#define KASAN_TAG_PGSHIFT (KASAN_TAG_PGOFF * (KASAN_TAG_WIDTH != 0)) + +/* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */ +#ifdef NODE_NOT_IN_PAGE_FLAGS +#define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT) +#define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF) ? \ + SECTIONS_PGOFF : ZONES_PGOFF) +#else +#define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT) +#define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF) ? \ + NODES_PGOFF : ZONES_PGOFF) +#endif + +#define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0)) + +#define ZONES_MASK ((1UL << ZONES_WIDTH) - 1) +#define NODES_MASK ((1UL << NODES_WIDTH) - 1) +#define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1) +#define LAST_CPUPID_MASK ((1UL << LAST_CPUPID_SHIFT) - 1) +#define KASAN_TAG_MASK ((1UL << KASAN_TAG_WIDTH) - 1) +#define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1) + +static inline enum zone_type page_zonenum(const struct page *page) +{ + ASSERT_EXCLUSIVE_BITS(page->flags, ZONES_MASK << ZONES_PGSHIFT); + return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; +} + +static inline enum zone_type folio_zonenum(const struct folio *folio) +{ + return page_zonenum(&folio->page); +} + +#ifdef CONFIG_ZONE_DEVICE +static inline bool is_zone_device_page(const struct page *page) +{ + return page_zonenum(page) == ZONE_DEVICE; +} + +/* + * Consecutive zone device pages should not be merged into the same sgl + * or bvec segment with other types of pages or if they belong to different + * pgmaps. Otherwise getting the pgmap of a given segment is not possible + * without scanning the entire segment. This helper returns true either if + * both pages are not zone device pages or both pages are zone device pages + * with the same pgmap. + */ +static inline bool zone_device_pages_have_same_pgmap(const struct page *a, + const struct page *b) +{ + if (is_zone_device_page(a) != is_zone_device_page(b)) + return false; + if (!is_zone_device_page(a)) + return true; + return a->pgmap == b->pgmap; +} + +extern void memmap_init_zone_device(struct zone *, unsigned long, + unsigned long, struct dev_pagemap *); +#else +static inline bool is_zone_device_page(const struct page *page) +{ + return false; +} +static inline bool zone_device_pages_have_same_pgmap(const struct page *a, + const struct page *b) +{ + return true; +} +#endif + +static inline bool folio_is_zone_device(const struct folio *folio) +{ + return is_zone_device_page(&folio->page); +} + +static inline bool is_zone_movable_page(const struct page *page) +{ + return page_zonenum(page) == ZONE_MOVABLE; +} + +static inline bool folio_is_zone_movable(const struct folio *folio) +{ + return folio_zonenum(folio) == ZONE_MOVABLE; +} +#endif + +/* + * 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]; +}; + +/* + * The array of struct pages for flatmem. + * It must be declared for SPARSEMEM as well because there are configurations + * that rely on that. + */ +extern struct page *mem_map; + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +struct deferred_split { + spinlock_t split_queue_lock; + struct list_head split_queue; + unsigned long split_queue_len; +}; +#endif + +#ifdef CONFIG_MEMORY_FAILURE +/* + * Per NUMA node memory failure handling statistics. + */ +struct memory_failure_stats { + /* + * Number of raw pages poisoned. + * Cases not accounted: memory outside kernel control, offline page, + * arch-specific memory_failure (SGX), hwpoison_filter() filtered + * error events, and unpoison actions from hwpoison_unpoison. + */ + unsigned long total; + /* + * Recovery results of poisoned raw pages handled by memory_failure, + * in sync with mf_result. + * total = ignored + failed + delayed + recovered. + * total * PAGE_SIZE * #nodes = /proc/meminfo/HardwareCorrupted. + */ + unsigned long ignored; + unsigned long failed; + unsigned long delayed; + unsigned long recovered; +}; +#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_FLATMEM /* 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; + + /* workqueues for throttling reclaim for different reasons. */ + wait_queue_head_t reclaim_wait[NR_VMSCAN_THROTTLE]; + + atomic_t nr_writeback_throttled;/* nr of writeback-throttled tasks */ + unsigned long nr_reclaim_start; /* nr pages written while throttled + * when throttling started. */ +#ifdef CONFIG_MEMORY_HOTPLUG + struct mutex kswapd_lock; +#endif + struct task_struct *kswapd; /* Protected by kswapd_lock */ + int kswapd_order; + enum zone_type kswapd_highest_zoneidx; + + int kswapd_failures; /* Number of 'reclaimed == 0' runs */ + +#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 */ + CACHELINE_PADDING(_pad1_); + +#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 + +#ifdef CONFIG_NUMA_BALANCING + /* start time in ms of current promote rate limit period */ + unsigned int nbp_rl_start; + /* number of promote candidate pages at start time of current rate limit period */ + unsigned long nbp_rl_nr_cand; + /* promote threshold in ms */ + unsigned int nbp_threshold; + /* start time in ms of current promote threshold adjustment period */ + unsigned int nbp_th_start; + /* + * number of promote candidate pages at start time of current promote + * threshold adjustment period + */ + unsigned long nbp_th_nr_cand; +#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; + +#ifdef CONFIG_LRU_GEN + /* kswap mm walk data */ + struct lru_gen_mm_walk mm_walk; + /* lru_gen_folio list */ + struct lru_gen_memcg memcg_lru; +#endif + + CACHELINE_PADDING(_pad2_); + + /* Per-node vmstats */ + struct per_cpu_nodestat __percpu *per_cpu_nodestats; + atomic_long_t vm_stat[NR_VM_NODE_STAT_ITEMS]; +#ifdef CONFIG_NUMA + struct memory_tier __rcu *memtier; +#endif +#ifdef CONFIG_MEMORY_FAILURE + struct memory_failure_stats mf_stats; +#endif +} 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) + +#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; +} + +#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 +} + +#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) + +#ifdef CONFIG_ZONE_DEVICE +static inline bool zone_is_zone_device(struct zone *zone) +{ + return zone_idx(zone) == ZONE_DEVICE; +} +#else +static inline bool zone_is_zone_device(struct zone *zone) +{ + return false; +} +#endif + +/* + * 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_NUMA +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; + +static inline int is_highmem_idx(enum zone_type idx) +{ +#ifdef CONFIG_HIGHMEM + return (idx == ZONE_HIGHMEM || + (idx == ZONE_MOVABLE && movable_zone == ZONE_HIGHMEM)); +#else + return 0; +#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 + * Return: 1 for a highmem zone, 0 otherwise + */ +static inline int is_highmem(struct zone *zone) +{ + return is_highmem_idx(zone_idx(zone)); +} + +#ifdef CONFIG_ZONE_DMA +bool has_managed_dma(void); +#else +static inline bool has_managed_dma(void) +{ + return false; +} +#endif + + +#ifndef CONFIG_NUMA + +extern struct pglist_data contig_page_data; +static inline struct pglist_data *NODE_DATA(int nid) +{ + return &contig_page_data; +} + +#else /* CONFIG_NUMA */ + +#include <asm/mmzone.h> + +#endif /* !CONFIG_NUMA */ + +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); + +/** + * 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. + * + * Return: the next zone at or below highest_zoneidx within the allowed + * nodemask using a cursor within a zonelist as a starting point + */ +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 + * + * 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. + * + * Return: Zoneref pointer for the first suitable zone found + */ +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) + +/* Whether the 'nodes' are all movable nodes */ +static inline bool movable_only_nodes(nodemask_t *nodes) +{ + struct zonelist *zonelist; + struct zoneref *z; + int nid; + + if (nodes_empty(*nodes)) + return false; + + /* + * We can chose arbitrary node from the nodemask to get a + * zonelist as they are interlinked. We just need to find + * at least one zone that can satisfy kernel allocations. + */ + nid = first_node(*nodes); + zonelist = &NODE_DATA(nid)->node_zonelists[ZONELIST_FALLBACK]; + z = first_zones_zonelist(zonelist, ZONE_NORMAL, nodes); + return (!z->zone) ? true : false; +} + + +#ifdef CONFIG_SPARSEMEM +#include <asm/sparsemem.h> +#endif + +#ifdef CONFIG_FLATMEM +#define pfn_to_nid(pfn) (0) +#endif + +#ifdef CONFIG_SPARSEMEM + +/* + * 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 + 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 { + struct rcu_head rcu; +#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 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 on all architectures. + * However, we can exceed 6 bits on some other architectures except + * powerpc (e.g. 15 bits are available on x86_64, 13 bits are available + * with the worst case of 64K pages on arm64) if we make sure the + * exceeded bit is not applicable to powerpc. + */ +enum { + SECTION_MARKED_PRESENT_BIT, + SECTION_HAS_MEM_MAP_BIT, + SECTION_IS_ONLINE_BIT, + SECTION_IS_EARLY_BIT, +#ifdef CONFIG_ZONE_DEVICE + SECTION_TAINT_ZONE_DEVICE_BIT, +#endif + SECTION_MAP_LAST_BIT, +}; + +#define SECTION_MARKED_PRESENT BIT(SECTION_MARKED_PRESENT_BIT) +#define SECTION_HAS_MEM_MAP BIT(SECTION_HAS_MEM_MAP_BIT) +#define SECTION_IS_ONLINE BIT(SECTION_IS_ONLINE_BIT) +#define SECTION_IS_EARLY BIT(SECTION_IS_EARLY_BIT) +#ifdef CONFIG_ZONE_DEVICE +#define SECTION_TAINT_ZONE_DEVICE BIT(SECTION_TAINT_ZONE_DEVICE_BIT) +#endif +#define SECTION_MAP_MASK (~(BIT(SECTION_MAP_LAST_BIT) - 1)) +#define SECTION_NID_SHIFT SECTION_MAP_LAST_BIT + +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)); +} + +#ifdef CONFIG_ZONE_DEVICE +static inline int online_device_section(struct mem_section *section) +{ + unsigned long flags = SECTION_IS_ONLINE | SECTION_TAINT_ZONE_DEVICE; + + return section && ((section->section_mem_map & flags) == flags); +} +#else +static inline int online_device_section(struct mem_section *section) +{ + return 0; +} +#endif + +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); +void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn); +#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, READ_ONCE(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 +/** + * pfn_valid - check if there is a valid memory map entry for a PFN + * @pfn: the page frame number to check + * + * Check if there is a valid memory map entry aka struct page for the @pfn. + * Note, that availability of the memory map entry does not imply that + * there is actual usable memory at that @pfn. The struct page may + * represent a hole or an unusable page frame. + * + * Return: 1 for PFNs that have memory map entries and 0 otherwise + */ +static inline int pfn_valid(unsigned long pfn) +{ + struct mem_section *ms; + int ret; + + /* + * Ensure the upper PAGE_SHIFT bits are clear in the + * pfn. Else it might lead to false positives when + * some of the upper bits are set, but the lower bits + * match a valid pfn. + */ + if (PHYS_PFN(PFN_PHYS(pfn)) != pfn) + return 0; + + if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS) + return 0; + ms = __pfn_to_section(pfn); + rcu_read_lock(); + if (!valid_section(ms)) { + rcu_read_unlock(); + return 0; + } + /* + * Traditionally early sections always returned pfn_valid() for + * the entire section-sized span. + */ + ret = early_section(ms) || pfn_section_valid(ms, pfn); + rcu_read_unlock(); + + return ret; +} +#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(__pfn_to_section(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 */ + +#endif /* !__GENERATING_BOUNDS.H */ +#endif /* !__ASSEMBLY__ */ +#endif /* _LINUX_MMZONE_H */ |