diff options
Diffstat (limited to '')
| -rw-r--r-- | mm/internal.h | 1157 |
1 files changed, 1157 insertions, 0 deletions
diff --git a/mm/internal.h b/mm/internal.h new file mode 100644 index 0000000000..30cf724ddb --- /dev/null +++ b/mm/internal.h @@ -0,0 +1,1157 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* internal.h: mm/ internal definitions + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ +#ifndef __MM_INTERNAL_H +#define __MM_INTERNAL_H + +#include <linux/fs.h> +#include <linux/mm.h> +#include <linux/pagemap.h> +#include <linux/rmap.h> +#include <linux/tracepoint-defs.h> + +struct folio_batch; + +/* + * The set of flags that only affect watermark checking and reclaim + * behaviour. This is used by the MM to obey the caller constraints + * about IO, FS and watermark checking while ignoring placement + * hints such as HIGHMEM usage. + */ +#define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\ + __GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\ + __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\ + __GFP_NOLOCKDEP) + +/* The GFP flags allowed during early boot */ +#define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS)) + +/* Control allocation cpuset and node placement constraints */ +#define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE) + +/* Do not use these with a slab allocator */ +#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) + +/* + * Different from WARN_ON_ONCE(), no warning will be issued + * when we specify __GFP_NOWARN. + */ +#define WARN_ON_ONCE_GFP(cond, gfp) ({ \ + static bool __section(".data.once") __warned; \ + int __ret_warn_once = !!(cond); \ + \ + if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \ + __warned = true; \ + WARN_ON(1); \ + } \ + unlikely(__ret_warn_once); \ +}) + +void page_writeback_init(void); + +/* + * If a 16GB hugetlb folio were mapped by PTEs of all of its 4kB pages, + * its nr_pages_mapped would be 0x400000: choose the COMPOUND_MAPPED bit + * above that range, instead of 2*(PMD_SIZE/PAGE_SIZE). Hugetlb currently + * leaves nr_pages_mapped at 0, but avoid surprise if it participates later. + */ +#define COMPOUND_MAPPED 0x800000 +#define FOLIO_PAGES_MAPPED (COMPOUND_MAPPED - 1) + +/* + * Flags passed to __show_mem() and show_free_areas() to suppress output in + * various contexts. + */ +#define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */ + +/* + * How many individual pages have an elevated _mapcount. Excludes + * the folio's entire_mapcount. + */ +static inline int folio_nr_pages_mapped(struct folio *folio) +{ + return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED; +} + +static inline void *folio_raw_mapping(struct folio *folio) +{ + unsigned long mapping = (unsigned long)folio->mapping; + + return (void *)(mapping & ~PAGE_MAPPING_FLAGS); +} + +void __acct_reclaim_writeback(pg_data_t *pgdat, struct folio *folio, + int nr_throttled); +static inline void acct_reclaim_writeback(struct folio *folio) +{ + pg_data_t *pgdat = folio_pgdat(folio); + int nr_throttled = atomic_read(&pgdat->nr_writeback_throttled); + + if (nr_throttled) + __acct_reclaim_writeback(pgdat, folio, nr_throttled); +} + +static inline void wake_throttle_isolated(pg_data_t *pgdat) +{ + wait_queue_head_t *wqh; + + wqh = &pgdat->reclaim_wait[VMSCAN_THROTTLE_ISOLATED]; + if (waitqueue_active(wqh)) + wake_up(wqh); +} + +vm_fault_t do_swap_page(struct vm_fault *vmf); +void folio_rotate_reclaimable(struct folio *folio); +bool __folio_end_writeback(struct folio *folio); +void deactivate_file_folio(struct folio *folio); +void folio_activate(struct folio *folio); + +void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas, + struct vm_area_struct *start_vma, unsigned long floor, + unsigned long ceiling, bool mm_wr_locked); +void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte); + +struct zap_details; +void unmap_page_range(struct mmu_gather *tlb, + struct vm_area_struct *vma, + unsigned long addr, unsigned long end, + struct zap_details *details); + +void page_cache_ra_order(struct readahead_control *, struct file_ra_state *, + unsigned int order); +void force_page_cache_ra(struct readahead_control *, unsigned long nr); +static inline void force_page_cache_readahead(struct address_space *mapping, + struct file *file, pgoff_t index, unsigned long nr_to_read) +{ + DEFINE_READAHEAD(ractl, file, &file->f_ra, mapping, index); + force_page_cache_ra(&ractl, nr_to_read); +} + +unsigned find_lock_entries(struct address_space *mapping, pgoff_t *start, + pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); +unsigned find_get_entries(struct address_space *mapping, pgoff_t *start, + pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices); +void filemap_free_folio(struct address_space *mapping, struct folio *folio); +int truncate_inode_folio(struct address_space *mapping, struct folio *folio); +bool truncate_inode_partial_folio(struct folio *folio, loff_t start, + loff_t end); +long invalidate_inode_page(struct page *page); +unsigned long mapping_try_invalidate(struct address_space *mapping, + pgoff_t start, pgoff_t end, unsigned long *nr_failed); + +/** + * folio_evictable - Test whether a folio is evictable. + * @folio: The folio to test. + * + * Test whether @folio is evictable -- i.e., should be placed on + * active/inactive lists vs unevictable list. + * + * Reasons folio might not be evictable: + * 1. folio's mapping marked unevictable + * 2. One of the pages in the folio is part of an mlocked VMA + */ +static inline bool folio_evictable(struct folio *folio) +{ + bool ret; + + /* Prevent address_space of inode and swap cache from being freed */ + rcu_read_lock(); + ret = !mapping_unevictable(folio_mapping(folio)) && + !folio_test_mlocked(folio); + rcu_read_unlock(); + return ret; +} + +/* + * Turn a non-refcounted page (->_refcount == 0) into refcounted with + * a count of one. + */ +static inline void set_page_refcounted(struct page *page) +{ + VM_BUG_ON_PAGE(PageTail(page), page); + VM_BUG_ON_PAGE(page_ref_count(page), page); + set_page_count(page, 1); +} + +/* + * Return true if a folio needs ->release_folio() calling upon it. + */ +static inline bool folio_needs_release(struct folio *folio) +{ + struct address_space *mapping = folio_mapping(folio); + + return folio_has_private(folio) || + (mapping && mapping_release_always(mapping)); +} + +extern unsigned long highest_memmap_pfn; + +/* + * Maximum number of reclaim retries without progress before the OOM + * killer is consider the only way forward. + */ +#define MAX_RECLAIM_RETRIES 16 + +/* + * in mm/vmscan.c: + */ +bool isolate_lru_page(struct page *page); +bool folio_isolate_lru(struct folio *folio); +void putback_lru_page(struct page *page); +void folio_putback_lru(struct folio *folio); +extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason); + +/* + * in mm/rmap.c: + */ +pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); + +/* + * in mm/page_alloc.c + */ +#define K(x) ((x) << (PAGE_SHIFT-10)) + +extern char * const zone_names[MAX_NR_ZONES]; + +/* perform sanity checks on struct pages being allocated or freed */ +DECLARE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled); + +extern int min_free_kbytes; + +void setup_per_zone_wmarks(void); +void calculate_min_free_kbytes(void); +int __meminit init_per_zone_wmark_min(void); +void page_alloc_sysctl_init(void); + +/* + * Structure for holding the mostly immutable allocation parameters passed + * between functions involved in allocations, including the alloc_pages* + * family of functions. + * + * nodemask, migratetype and highest_zoneidx are initialized only once in + * __alloc_pages() and then never change. + * + * zonelist, preferred_zone and highest_zoneidx are set first in + * __alloc_pages() for the fast path, and might be later changed + * in __alloc_pages_slowpath(). All other functions pass the whole structure + * by a const pointer. + */ +struct alloc_context { + struct zonelist *zonelist; + nodemask_t *nodemask; + struct zoneref *preferred_zoneref; + int migratetype; + + /* + * highest_zoneidx represents highest usable zone index of + * the allocation request. Due to the nature of the zone, + * memory on lower zone than the highest_zoneidx will be + * protected by lowmem_reserve[highest_zoneidx]. + * + * highest_zoneidx is also used by reclaim/compaction to limit + * the target zone since higher zone than this index cannot be + * usable for this allocation request. + */ + enum zone_type highest_zoneidx; + bool spread_dirty_pages; +}; + +/* + * This function returns the order of a free page in the buddy system. In + * general, page_zone(page)->lock must be held by the caller to prevent the + * page from being allocated in parallel and returning garbage as the order. + * If a caller does not hold page_zone(page)->lock, it must guarantee that the + * page cannot be allocated or merged in parallel. Alternatively, it must + * handle invalid values gracefully, and use buddy_order_unsafe() below. + */ +static inline unsigned int buddy_order(struct page *page) +{ + /* PageBuddy() must be checked by the caller */ + return page_private(page); +} + +/* + * Like buddy_order(), but for callers who cannot afford to hold the zone lock. + * PageBuddy() should be checked first by the caller to minimize race window, + * and invalid values must be handled gracefully. + * + * READ_ONCE is used so that if the caller assigns the result into a local + * variable and e.g. tests it for valid range before using, the compiler cannot + * decide to remove the variable and inline the page_private(page) multiple + * times, potentially observing different values in the tests and the actual + * use of the result. + */ +#define buddy_order_unsafe(page) READ_ONCE(page_private(page)) + +/* + * This function checks whether a page is free && is the buddy + * we can coalesce a page and its buddy if + * (a) the buddy is not in a hole (check before calling!) && + * (b) the buddy is in the buddy system && + * (c) a page and its buddy have the same order && + * (d) a page and its buddy are in the same zone. + * + * For recording whether a page is in the buddy system, we set PageBuddy. + * Setting, clearing, and testing PageBuddy is serialized by zone->lock. + * + * For recording page's order, we use page_private(page). + */ +static inline bool page_is_buddy(struct page *page, struct page *buddy, + unsigned int order) +{ + if (!page_is_guard(buddy) && !PageBuddy(buddy)) + return false; + + if (buddy_order(buddy) != order) + return false; + + /* + * zone check is done late to avoid uselessly calculating + * zone/node ids for pages that could never merge. + */ + if (page_zone_id(page) != page_zone_id(buddy)) + return false; + + VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); + + return true; +} + +/* + * Locate the struct page for both the matching buddy in our + * pair (buddy1) and the combined O(n+1) page they form (page). + * + * 1) Any buddy B1 will have an order O twin B2 which satisfies + * the following equation: + * B2 = B1 ^ (1 << O) + * For example, if the starting buddy (buddy2) is #8 its order + * 1 buddy is #10: + * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 + * + * 2) Any buddy B will have an order O+1 parent P which + * satisfies the following equation: + * P = B & ~(1 << O) + * + * Assumption: *_mem_map is contiguous at least up to MAX_ORDER + */ +static inline unsigned long +__find_buddy_pfn(unsigned long page_pfn, unsigned int order) +{ + return page_pfn ^ (1 << order); +} + +/* + * Find the buddy of @page and validate it. + * @page: The input page + * @pfn: The pfn of the page, it saves a call to page_to_pfn() when the + * function is used in the performance-critical __free_one_page(). + * @order: The order of the page + * @buddy_pfn: The output pointer to the buddy pfn, it also saves a call to + * page_to_pfn(). + * + * The found buddy can be a non PageBuddy, out of @page's zone, or its order is + * not the same as @page. The validation is necessary before use it. + * + * Return: the found buddy page or NULL if not found. + */ +static inline struct page *find_buddy_page_pfn(struct page *page, + unsigned long pfn, unsigned int order, unsigned long *buddy_pfn) +{ + unsigned long __buddy_pfn = __find_buddy_pfn(pfn, order); + struct page *buddy; + + buddy = page + (__buddy_pfn - pfn); + if (buddy_pfn) + *buddy_pfn = __buddy_pfn; + + if (page_is_buddy(page, buddy, order)) + return buddy; + return NULL; +} + +extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn, + unsigned long end_pfn, struct zone *zone); + +static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn, + unsigned long end_pfn, struct zone *zone) +{ + if (zone->contiguous) + return pfn_to_page(start_pfn); + + return __pageblock_pfn_to_page(start_pfn, end_pfn, zone); +} + +void set_zone_contiguous(struct zone *zone); + +static inline void clear_zone_contiguous(struct zone *zone) +{ + zone->contiguous = false; +} + +extern int __isolate_free_page(struct page *page, unsigned int order); +extern void __putback_isolated_page(struct page *page, unsigned int order, + int mt); +extern void memblock_free_pages(struct page *page, unsigned long pfn, + unsigned int order); +extern void __free_pages_core(struct page *page, unsigned int order); + +/* + * This will have no effect, other than possibly generating a warning, if the + * caller passes in a non-large folio. + */ +static inline void folio_set_order(struct folio *folio, unsigned int order) +{ + if (WARN_ON_ONCE(!order || !folio_test_large(folio))) + return; + + folio->_flags_1 = (folio->_flags_1 & ~0xffUL) | order; +#ifdef CONFIG_64BIT + folio->_folio_nr_pages = 1U << order; +#endif +} + +void folio_undo_large_rmappable(struct folio *folio); + +static inline void prep_compound_head(struct page *page, unsigned int order) +{ + struct folio *folio = (struct folio *)page; + + folio_set_order(folio, order); + atomic_set(&folio->_entire_mapcount, -1); + atomic_set(&folio->_nr_pages_mapped, 0); + atomic_set(&folio->_pincount, 0); +} + +static inline void prep_compound_tail(struct page *head, int tail_idx) +{ + struct page *p = head + tail_idx; + + p->mapping = TAIL_MAPPING; + set_compound_head(p, head); + set_page_private(p, 0); +} + +extern void prep_compound_page(struct page *page, unsigned int order); + +extern void post_alloc_hook(struct page *page, unsigned int order, + gfp_t gfp_flags); +extern int user_min_free_kbytes; + +extern void free_unref_page(struct page *page, unsigned int order); +extern void free_unref_page_list(struct list_head *list); + +extern void zone_pcp_reset(struct zone *zone); +extern void zone_pcp_disable(struct zone *zone); +extern void zone_pcp_enable(struct zone *zone); +extern void zone_pcp_init(struct zone *zone); + +extern void *memmap_alloc(phys_addr_t size, phys_addr_t align, + phys_addr_t min_addr, + int nid, bool exact_nid); + +void memmap_init_range(unsigned long, int, unsigned long, unsigned long, + unsigned long, enum meminit_context, struct vmem_altmap *, int); + + +int split_free_page(struct page *free_page, + unsigned int order, unsigned long split_pfn_offset); + +#if defined CONFIG_COMPACTION || defined CONFIG_CMA + +/* + * in mm/compaction.c + */ +/* + * compact_control is used to track pages being migrated and the free pages + * they are being migrated to during memory compaction. The free_pfn starts + * at the end of a zone and migrate_pfn begins at the start. Movable pages + * are moved to the end of a zone during a compaction run and the run + * completes when free_pfn <= migrate_pfn + */ +struct compact_control { + struct list_head freepages; /* List of free pages to migrate to */ + struct list_head migratepages; /* List of pages being migrated */ + unsigned int nr_freepages; /* Number of isolated free pages */ + unsigned int nr_migratepages; /* Number of pages to migrate */ + unsigned long free_pfn; /* isolate_freepages search base */ + /* + * Acts as an in/out parameter to page isolation for migration. + * isolate_migratepages uses it as a search base. + * isolate_migratepages_block will update the value to the next pfn + * after the last isolated one. + */ + unsigned long migrate_pfn; + unsigned long fast_start_pfn; /* a pfn to start linear scan from */ + struct zone *zone; + unsigned long total_migrate_scanned; + unsigned long total_free_scanned; + unsigned short fast_search_fail;/* failures to use free list searches */ + short search_order; /* order to start a fast search at */ + const gfp_t gfp_mask; /* gfp mask of a direct compactor */ + int order; /* order a direct compactor needs */ + int migratetype; /* migratetype of direct compactor */ + const unsigned int alloc_flags; /* alloc flags of a direct compactor */ + const int highest_zoneidx; /* zone index of a direct compactor */ + enum migrate_mode mode; /* Async or sync migration mode */ + bool ignore_skip_hint; /* Scan blocks even if marked skip */ + bool no_set_skip_hint; /* Don't mark blocks for skipping */ + bool ignore_block_suitable; /* Scan blocks considered unsuitable */ + bool direct_compaction; /* False from kcompactd or /proc/... */ + bool proactive_compaction; /* kcompactd proactive compaction */ + bool whole_zone; /* Whole zone should/has been scanned */ + bool contended; /* Signal lock contention */ + bool finish_pageblock; /* Scan the remainder of a pageblock. Used + * when there are potentially transient + * isolation or migration failures to + * ensure forward progress. + */ + bool alloc_contig; /* alloc_contig_range allocation */ +}; + +/* + * Used in direct compaction when a page should be taken from the freelists + * immediately when one is created during the free path. + */ +struct capture_control { + struct compact_control *cc; + struct page *page; +}; + +unsigned long +isolate_freepages_range(struct compact_control *cc, + unsigned long start_pfn, unsigned long end_pfn); +int +isolate_migratepages_range(struct compact_control *cc, + unsigned long low_pfn, unsigned long end_pfn); + +int __alloc_contig_migrate_range(struct compact_control *cc, + unsigned long start, unsigned long end); + +/* Free whole pageblock and set its migration type to MIGRATE_CMA. */ +void init_cma_reserved_pageblock(struct page *page); + +#endif /* CONFIG_COMPACTION || CONFIG_CMA */ + +int find_suitable_fallback(struct free_area *area, unsigned int order, + int migratetype, bool only_stealable, bool *can_steal); + +static inline bool free_area_empty(struct free_area *area, int migratetype) +{ + return list_empty(&area->free_list[migratetype]); +} + +/* + * These three helpers classifies VMAs for virtual memory accounting. + */ + +/* + * Executable code area - executable, not writable, not stack + */ +static inline bool is_exec_mapping(vm_flags_t flags) +{ + return (flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC; +} + +/* + * Stack area (including shadow stacks) + * + * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous: + * do_mmap() forbids all other combinations. + */ +static inline bool is_stack_mapping(vm_flags_t flags) +{ + return ((flags & VM_STACK) == VM_STACK) || (flags & VM_SHADOW_STACK); +} + +/* + * Data area - private, writable, not stack + */ +static inline bool is_data_mapping(vm_flags_t flags) +{ + return (flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE; +} + +/* mm/util.c */ +struct anon_vma *folio_anon_vma(struct folio *folio); + +#ifdef CONFIG_MMU +void unmap_mapping_folio(struct folio *folio); +extern long populate_vma_page_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end, int *locked); +extern long faultin_vma_page_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end, + bool write, int *locked); +extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags, + unsigned long bytes); +/* + * mlock_vma_folio() and munlock_vma_folio(): + * should be called with vma's mmap_lock held for read or write, + * under page table lock for the pte/pmd being added or removed. + * + * mlock is usually called at the end of page_add_*_rmap(), munlock at + * the end of page_remove_rmap(); but new anon folios are managed by + * folio_add_lru_vma() calling mlock_new_folio(). + * + * @compound is used to include pmd mappings of THPs, but filter out + * pte mappings of THPs, which cannot be consistently counted: a pte + * mapping of the THP head cannot be distinguished by the page alone. + */ +void mlock_folio(struct folio *folio); +static inline void mlock_vma_folio(struct folio *folio, + struct vm_area_struct *vma, bool compound) +{ + /* + * The VM_SPECIAL check here serves two purposes. + * 1) VM_IO check prevents migration from double-counting during mlock. + * 2) Although mmap_region() and mlock_fixup() take care that VM_LOCKED + * is never left set on a VM_SPECIAL vma, there is an interval while + * file->f_op->mmap() is using vm_insert_page(s), when VM_LOCKED may + * still be set while VM_SPECIAL bits are added: so ignore it then. + */ + if (unlikely((vma->vm_flags & (VM_LOCKED|VM_SPECIAL)) == VM_LOCKED) && + (compound || !folio_test_large(folio))) + mlock_folio(folio); +} + +void munlock_folio(struct folio *folio); +static inline void munlock_vma_folio(struct folio *folio, + struct vm_area_struct *vma, bool compound) +{ + if (unlikely(vma->vm_flags & VM_LOCKED) && + (compound || !folio_test_large(folio))) + munlock_folio(folio); +} + +void mlock_new_folio(struct folio *folio); +bool need_mlock_drain(int cpu); +void mlock_drain_local(void); +void mlock_drain_remote(int cpu); + +extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma); + +/* + * Return the start of user virtual address at the specific offset within + * a vma. + */ +static inline unsigned long +vma_pgoff_address(pgoff_t pgoff, unsigned long nr_pages, + struct vm_area_struct *vma) +{ + unsigned long address; + + if (pgoff >= vma->vm_pgoff) { + address = vma->vm_start + + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); + /* Check for address beyond vma (or wrapped through 0?) */ + if (address < vma->vm_start || address >= vma->vm_end) + address = -EFAULT; + } else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) { + /* Test above avoids possibility of wrap to 0 on 32-bit */ + address = vma->vm_start; + } else { + address = -EFAULT; + } + return address; +} + +/* + * Return the start of user virtual address of a page within a vma. + * Returns -EFAULT if all of the page is outside the range of vma. + * If page is a compound head, the entire compound page is considered. + */ +static inline unsigned long +vma_address(struct page *page, struct vm_area_struct *vma) +{ + VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */ + return vma_pgoff_address(page_to_pgoff(page), compound_nr(page), vma); +} + +/* + * Then at what user virtual address will none of the range be found in vma? + * Assumes that vma_address() already returned a good starting address. + */ +static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw) +{ + struct vm_area_struct *vma = pvmw->vma; + pgoff_t pgoff; + unsigned long address; + + /* Common case, plus ->pgoff is invalid for KSM */ + if (pvmw->nr_pages == 1) + return pvmw->address + PAGE_SIZE; + + pgoff = pvmw->pgoff + pvmw->nr_pages; + address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); + /* Check for address beyond vma (or wrapped through 0?) */ + if (address < vma->vm_start || address > vma->vm_end) + address = vma->vm_end; + return address; +} + +static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf, + struct file *fpin) +{ + int flags = vmf->flags; + + if (fpin) + return fpin; + + /* + * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or + * anything, so we only pin the file and drop the mmap_lock if only + * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt. + */ + if (fault_flag_allow_retry_first(flags) && + !(flags & FAULT_FLAG_RETRY_NOWAIT)) { + fpin = get_file(vmf->vma->vm_file); + release_fault_lock(vmf); + } + return fpin; +} +#else /* !CONFIG_MMU */ +static inline void unmap_mapping_folio(struct folio *folio) { } +static inline void mlock_new_folio(struct folio *folio) { } +static inline bool need_mlock_drain(int cpu) { return false; } +static inline void mlock_drain_local(void) { } +static inline void mlock_drain_remote(int cpu) { } +static inline void vunmap_range_noflush(unsigned long start, unsigned long end) +{ +} +#endif /* !CONFIG_MMU */ + +/* Memory initialisation debug and verification */ +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT +DECLARE_STATIC_KEY_TRUE(deferred_pages); + +bool __init deferred_grow_zone(struct zone *zone, unsigned int order); +#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ + +enum mminit_level { + MMINIT_WARNING, + MMINIT_VERIFY, + MMINIT_TRACE +}; + +#ifdef CONFIG_DEBUG_MEMORY_INIT + +extern int mminit_loglevel; + +#define mminit_dprintk(level, prefix, fmt, arg...) \ +do { \ + if (level < mminit_loglevel) { \ + if (level <= MMINIT_WARNING) \ + pr_warn("mminit::" prefix " " fmt, ##arg); \ + else \ + printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \ + } \ +} while (0) + +extern void mminit_verify_pageflags_layout(void); +extern void mminit_verify_zonelist(void); +#else + +static inline void mminit_dprintk(enum mminit_level level, + const char *prefix, const char *fmt, ...) +{ +} + +static inline void mminit_verify_pageflags_layout(void) +{ +} + +static inline void mminit_verify_zonelist(void) +{ +} +#endif /* CONFIG_DEBUG_MEMORY_INIT */ + +#define NODE_RECLAIM_NOSCAN -2 +#define NODE_RECLAIM_FULL -1 +#define NODE_RECLAIM_SOME 0 +#define NODE_RECLAIM_SUCCESS 1 + +#ifdef CONFIG_NUMA +extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int); +extern int find_next_best_node(int node, nodemask_t *used_node_mask); +#else +static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask, + unsigned int order) +{ + return NODE_RECLAIM_NOSCAN; +} +static inline int find_next_best_node(int node, nodemask_t *used_node_mask) +{ + return NUMA_NO_NODE; +} +#endif + +/* + * mm/memory-failure.c + */ +extern int hwpoison_filter(struct page *p); + +extern u32 hwpoison_filter_dev_major; +extern u32 hwpoison_filter_dev_minor; +extern u64 hwpoison_filter_flags_mask; +extern u64 hwpoison_filter_flags_value; +extern u64 hwpoison_filter_memcg; +extern u32 hwpoison_filter_enable; + +extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, + unsigned long, unsigned long, + unsigned long, unsigned long); + +extern void set_pageblock_order(void); +unsigned long reclaim_pages(struct list_head *folio_list); +unsigned int reclaim_clean_pages_from_list(struct zone *zone, + struct list_head *folio_list); +/* The ALLOC_WMARK bits are used as an index to zone->watermark */ +#define ALLOC_WMARK_MIN WMARK_MIN +#define ALLOC_WMARK_LOW WMARK_LOW +#define ALLOC_WMARK_HIGH WMARK_HIGH +#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */ + +/* Mask to get the watermark bits */ +#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) + +/* + * Only MMU archs have async oom victim reclaim - aka oom_reaper so we + * cannot assume a reduced access to memory reserves is sufficient for + * !MMU + */ +#ifdef CONFIG_MMU +#define ALLOC_OOM 0x08 +#else +#define ALLOC_OOM ALLOC_NO_WATERMARKS +#endif + +#define ALLOC_NON_BLOCK 0x10 /* Caller cannot block. Allow access + * to 25% of the min watermark or + * 62.5% if __GFP_HIGH is set. + */ +#define ALLOC_MIN_RESERVE 0x20 /* __GFP_HIGH set. Allow access to 50% + * of the min watermark. + */ +#define ALLOC_CPUSET 0x40 /* check for correct cpuset */ +#define ALLOC_CMA 0x80 /* allow allocations from CMA areas */ +#ifdef CONFIG_ZONE_DMA32 +#define ALLOC_NOFRAGMENT 0x100 /* avoid mixing pageblock types */ +#else +#define ALLOC_NOFRAGMENT 0x0 +#endif +#define ALLOC_HIGHATOMIC 0x200 /* Allows access to MIGRATE_HIGHATOMIC */ +#define ALLOC_KSWAPD 0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */ + +/* Flags that allow allocations below the min watermark. */ +#define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM) + +enum ttu_flags; +struct tlbflush_unmap_batch; + + +/* + * only for MM internal work items which do not depend on + * any allocations or locks which might depend on allocations + */ +extern struct workqueue_struct *mm_percpu_wq; + +#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH +void try_to_unmap_flush(void); +void try_to_unmap_flush_dirty(void); +void flush_tlb_batched_pending(struct mm_struct *mm); +#else +static inline void try_to_unmap_flush(void) +{ +} +static inline void try_to_unmap_flush_dirty(void) +{ +} +static inline void flush_tlb_batched_pending(struct mm_struct *mm) +{ +} +#endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ + +extern const struct trace_print_flags pageflag_names[]; +extern const struct trace_print_flags pagetype_names[]; +extern const struct trace_print_flags vmaflag_names[]; +extern const struct trace_print_flags gfpflag_names[]; + +static inline bool is_migrate_highatomic(enum migratetype migratetype) +{ + return migratetype == MIGRATE_HIGHATOMIC; +} + +static inline bool is_migrate_highatomic_page(struct page *page) +{ + return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC; +} + +void setup_zone_pageset(struct zone *zone); + +struct migration_target_control { + int nid; /* preferred node id */ + nodemask_t *nmask; + gfp_t gfp_mask; +}; + +/* + * mm/filemap.c + */ +size_t splice_folio_into_pipe(struct pipe_inode_info *pipe, + struct folio *folio, loff_t fpos, size_t size); + +/* + * mm/vmalloc.c + */ +#ifdef CONFIG_MMU +void __init vmalloc_init(void); +int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, + pgprot_t prot, struct page **pages, unsigned int page_shift); +#else +static inline void vmalloc_init(void) +{ +} + +static inline +int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end, + pgprot_t prot, struct page **pages, unsigned int page_shift) +{ + return -EINVAL; +} +#endif + +int __must_check __vmap_pages_range_noflush(unsigned long addr, + unsigned long end, pgprot_t prot, + struct page **pages, unsigned int page_shift); + +void vunmap_range_noflush(unsigned long start, unsigned long end); + +void __vunmap_range_noflush(unsigned long start, unsigned long end); + +int numa_migrate_prep(struct page *page, struct vm_area_struct *vma, + unsigned long addr, int page_nid, int *flags); + +void free_zone_device_page(struct page *page); +int migrate_device_coherent_page(struct page *page); + +/* + * mm/gup.c + */ +struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags); +int __must_check try_grab_page(struct page *page, unsigned int flags); + +/* + * mm/huge_memory.c + */ +struct page *follow_trans_huge_pmd(struct vm_area_struct *vma, + unsigned long addr, pmd_t *pmd, + unsigned int flags); + +enum { + /* mark page accessed */ + FOLL_TOUCH = 1 << 16, + /* a retry, previous pass started an IO */ + FOLL_TRIED = 1 << 17, + /* we are working on non-current tsk/mm */ + FOLL_REMOTE = 1 << 18, + /* pages must be released via unpin_user_page */ + FOLL_PIN = 1 << 19, + /* gup_fast: prevent fall-back to slow gup */ + FOLL_FAST_ONLY = 1 << 20, + /* allow unlocking the mmap lock */ + FOLL_UNLOCKABLE = 1 << 21, +}; + +/* + * Indicates for which pages that are write-protected in the page table, + * whether GUP has to trigger unsharing via FAULT_FLAG_UNSHARE such that the + * GUP pin will remain consistent with the pages mapped into the page tables + * of the MM. + * + * Temporary unmapping of PageAnonExclusive() pages or clearing of + * PageAnonExclusive() has to protect against concurrent GUP: + * * Ordinary GUP: Using the PT lock + * * GUP-fast and fork(): mm->write_protect_seq + * * GUP-fast and KSM or temporary unmapping (swap, migration): see + * page_try_share_anon_rmap() + * + * Must be called with the (sub)page that's actually referenced via the + * page table entry, which might not necessarily be the head page for a + * PTE-mapped THP. + * + * If the vma is NULL, we're coming from the GUP-fast path and might have + * to fallback to the slow path just to lookup the vma. + */ +static inline bool gup_must_unshare(struct vm_area_struct *vma, + unsigned int flags, struct page *page) +{ + /* + * FOLL_WRITE is implicitly handled correctly as the page table entry + * has to be writable -- and if it references (part of) an anonymous + * folio, that part is required to be marked exclusive. + */ + if ((flags & (FOLL_WRITE | FOLL_PIN)) != FOLL_PIN) + return false; + /* + * Note: PageAnon(page) is stable until the page is actually getting + * freed. + */ + if (!PageAnon(page)) { + /* + * We only care about R/O long-term pining: R/O short-term + * pinning does not have the semantics to observe successive + * changes through the process page tables. + */ + if (!(flags & FOLL_LONGTERM)) + return false; + + /* We really need the vma ... */ + if (!vma) + return true; + + /* + * ... because we only care about writable private ("COW") + * mappings where we have to break COW early. + */ + return is_cow_mapping(vma->vm_flags); + } + + /* Paired with a memory barrier in page_try_share_anon_rmap(). */ + if (IS_ENABLED(CONFIG_HAVE_FAST_GUP)) + smp_rmb(); + + /* + * During GUP-fast we might not get called on the head page for a + * hugetlb page that is mapped using cont-PTE, because GUP-fast does + * not work with the abstracted hugetlb PTEs that always point at the + * head page. For hugetlb, PageAnonExclusive only applies on the head + * page (as it cannot be partially COW-shared), so lookup the head page. + */ + if (unlikely(!PageHead(page) && PageHuge(page))) + page = compound_head(page); + + /* + * Note that PageKsm() pages cannot be exclusive, and consequently, + * cannot get pinned. + */ + return !PageAnonExclusive(page); +} + +extern bool mirrored_kernelcore; +extern bool memblock_has_mirror(void); + +static inline bool vma_soft_dirty_enabled(struct vm_area_struct *vma) +{ + /* + * NOTE: we must check this before VM_SOFTDIRTY on soft-dirty + * enablements, because when without soft-dirty being compiled in, + * VM_SOFTDIRTY is defined as 0x0, then !(vm_flags & VM_SOFTDIRTY) + * will be constantly true. + */ + if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY)) + return false; + + /* + * Soft-dirty is kind of special: its tracking is enabled when the + * vma flags not set. + */ + return !(vma->vm_flags & VM_SOFTDIRTY); +} + +static inline void vma_iter_config(struct vma_iterator *vmi, + unsigned long index, unsigned long last) +{ + MAS_BUG_ON(&vmi->mas, vmi->mas.node != MAS_START && + (vmi->mas.index > index || vmi->mas.last < index)); + __mas_set_range(&vmi->mas, index, last - 1); +} + +/* + * VMA Iterator functions shared between nommu and mmap + */ +static inline int vma_iter_prealloc(struct vma_iterator *vmi, + struct vm_area_struct *vma) +{ + return mas_preallocate(&vmi->mas, vma, GFP_KERNEL); +} + +static inline void vma_iter_clear(struct vma_iterator *vmi) +{ + mas_store_prealloc(&vmi->mas, NULL); +} + +static inline int vma_iter_clear_gfp(struct vma_iterator *vmi, + unsigned long start, unsigned long end, gfp_t gfp) +{ + __mas_set_range(&vmi->mas, start, end - 1); + mas_store_gfp(&vmi->mas, NULL, gfp); + if (unlikely(mas_is_err(&vmi->mas))) + return -ENOMEM; + + return 0; +} + +static inline struct vm_area_struct *vma_iter_load(struct vma_iterator *vmi) +{ + return mas_walk(&vmi->mas); +} + +/* Store a VMA with preallocated memory */ +static inline void vma_iter_store(struct vma_iterator *vmi, + struct vm_area_struct *vma) +{ + +#if defined(CONFIG_DEBUG_VM_MAPLE_TREE) + if (MAS_WARN_ON(&vmi->mas, vmi->mas.node != MAS_START && + vmi->mas.index > vma->vm_start)) { + pr_warn("%lx > %lx\n store vma %lx-%lx\n into slot %lx-%lx\n", + vmi->mas.index, vma->vm_start, vma->vm_start, + vma->vm_end, vmi->mas.index, vmi->mas.last); + } + if (MAS_WARN_ON(&vmi->mas, vmi->mas.node != MAS_START && + vmi->mas.last < vma->vm_start)) { + pr_warn("%lx < %lx\nstore vma %lx-%lx\ninto slot %lx-%lx\n", + vmi->mas.last, vma->vm_start, vma->vm_start, vma->vm_end, + vmi->mas.index, vmi->mas.last); + } +#endif + + if (vmi->mas.node != MAS_START && + ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) + vma_iter_invalidate(vmi); + + __mas_set_range(&vmi->mas, vma->vm_start, vma->vm_end - 1); + mas_store_prealloc(&vmi->mas, vma); +} + +static inline int vma_iter_store_gfp(struct vma_iterator *vmi, + struct vm_area_struct *vma, gfp_t gfp) +{ + if (vmi->mas.node != MAS_START && + ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start))) + vma_iter_invalidate(vmi); + + __mas_set_range(&vmi->mas, vma->vm_start, vma->vm_end - 1); + mas_store_gfp(&vmi->mas, vma, gfp); + if (unlikely(mas_is_err(&vmi->mas))) + return -ENOMEM; + + return 0; +} + +/* + * VMA lock generalization + */ +struct vma_prepare { + struct vm_area_struct *vma; + struct vm_area_struct *adj_next; + struct file *file; + struct address_space *mapping; + struct anon_vma *anon_vma; + struct vm_area_struct *insert; + struct vm_area_struct *remove; + struct vm_area_struct *remove2; +}; +#endif /* __MM_INTERNAL_H */ |