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1/* SPDX-License-Identifier: GPL-2.0-or-later */2/* internal.h: mm/ internal definitions3 *4 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.5 * Written by David Howells (dhowells@redhat.com)6 */7#ifndef __MM_INTERNAL_H8#define __MM_INTERNAL_H9 10#include <linux/fs.h>11#include <linux/khugepaged.h>12#include <linux/mm.h>13#include <linux/mm_inline.h>14#include <linux/pagemap.h>15#include <linux/rmap.h>16#include <linux/swap.h>17#include <linux/swapops.h>18#include <linux/swap_cgroup.h>19#include <linux/tracepoint-defs.h>20 21/* Internal core VMA manipulation functions. */22#include "vma.h"23 24struct folio_batch;25 26/*27 * The set of flags that only affect watermark checking and reclaim28 * behaviour. This is used by the MM to obey the caller constraints29 * about IO, FS and watermark checking while ignoring placement30 * hints such as HIGHMEM usage.31 */32#define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\33			__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\34			__GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\35			__GFP_NOLOCKDEP)36 37/* The GFP flags allowed during early boot */38#define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS))39 40/* Control allocation cpuset and node placement constraints */41#define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)42 43/* Do not use these with a slab allocator */44#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)45 46/*47 * Different from WARN_ON_ONCE(), no warning will be issued48 * when we specify __GFP_NOWARN.49 */50#define WARN_ON_ONCE_GFP(cond, gfp)	({				\51	static bool __section(".data.once") __warned;			\52	int __ret_warn_once = !!(cond);					\53									\54	if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \55		__warned = true;					\56		WARN_ON(1);						\57	}								\58	unlikely(__ret_warn_once);					\59})60 61void page_writeback_init(void);62 63/*64 * If a 16GB hugetlb folio were mapped by PTEs of all of its 4kB pages,65 * its nr_pages_mapped would be 0x400000: choose the ENTIRELY_MAPPED bit66 * above that range, instead of 2*(PMD_SIZE/PAGE_SIZE).  Hugetlb currently67 * leaves nr_pages_mapped at 0, but avoid surprise if it participates later.68 */69#define ENTIRELY_MAPPED		0x80000070#define FOLIO_PAGES_MAPPED	(ENTIRELY_MAPPED - 1)71 72/*73 * Flags passed to __show_mem() and show_free_areas() to suppress output in74 * various contexts.75 */76#define SHOW_MEM_FILTER_NODES		(0x0001u)	/* disallowed nodes */77 78/*79 * How many individual pages have an elevated _mapcount.  Excludes80 * the folio's entire_mapcount.81 *82 * Don't use this function outside of debugging code.83 */84static inline int folio_nr_pages_mapped(const struct folio *folio)85{86	return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED;87}88 89/*90 * Retrieve the first entry of a folio based on a provided entry within the91 * folio. We cannot rely on folio->swap as there is no guarantee that it has92 * been initialized. Used for calling arch_swap_restore()93 */94static inline swp_entry_t folio_swap(swp_entry_t entry,95		const struct folio *folio)96{97	swp_entry_t swap = {98		.val = ALIGN_DOWN(entry.val, folio_nr_pages(folio)),99	};100 101	return swap;102}103 104static inline void *folio_raw_mapping(const struct folio *folio)105{106	unsigned long mapping = (unsigned long)folio->mapping;107 108	return (void *)(mapping & ~PAGE_MAPPING_FLAGS);109}110 111/*112 * This is a file-backed mapping, and is about to be memory mapped - invoke its113 * mmap hook and safely handle error conditions. On error, VMA hooks will be114 * mutated.115 *116 * @file: File which backs the mapping.117 * @vma:  VMA which we are mapping.118 *119 * Returns: 0 if success, error otherwise.120 */121static inline int mmap_file(struct file *file, struct vm_area_struct *vma)122{123	int err = call_mmap(file, vma);124 125	if (likely(!err))126		return 0;127 128	/*129	 * OK, we tried to call the file hook for mmap(), but an error130	 * arose. The mapping is in an inconsistent state and we most not invoke131	 * any further hooks on it.132	 */133	vma->vm_ops = &vma_dummy_vm_ops;134 135	return err;136}137 138/*139 * If the VMA has a close hook then close it, and since closing it might leave140 * it in an inconsistent state which makes the use of any hooks suspect, clear141 * them down by installing dummy empty hooks.142 */143static inline void vma_close(struct vm_area_struct *vma)144{145	if (vma->vm_ops && vma->vm_ops->close) {146		vma->vm_ops->close(vma);147 148		/*149		 * The mapping is in an inconsistent state, and no further hooks150		 * may be invoked upon it.151		 */152		vma->vm_ops = &vma_dummy_vm_ops;153	}154}155 156#ifdef CONFIG_MMU157 158/* Flags for folio_pte_batch(). */159typedef int __bitwise fpb_t;160 161/* Compare PTEs after pte_mkclean(), ignoring the dirty bit. */162#define FPB_IGNORE_DIRTY		((__force fpb_t)BIT(0))163 164/* Compare PTEs after pte_clear_soft_dirty(), ignoring the soft-dirty bit. */165#define FPB_IGNORE_SOFT_DIRTY		((__force fpb_t)BIT(1))166 167static inline pte_t __pte_batch_clear_ignored(pte_t pte, fpb_t flags)168{169	if (flags & FPB_IGNORE_DIRTY)170		pte = pte_mkclean(pte);171	if (likely(flags & FPB_IGNORE_SOFT_DIRTY))172		pte = pte_clear_soft_dirty(pte);173	return pte_wrprotect(pte_mkold(pte));174}175 176/**177 * folio_pte_batch - detect a PTE batch for a large folio178 * @folio: The large folio to detect a PTE batch for.179 * @addr: The user virtual address the first page is mapped at.180 * @start_ptep: Page table pointer for the first entry.181 * @pte: Page table entry for the first page.182 * @max_nr: The maximum number of table entries to consider.183 * @flags: Flags to modify the PTE batch semantics.184 * @any_writable: Optional pointer to indicate whether any entry except the185 *		  first one is writable.186 * @any_young: Optional pointer to indicate whether any entry except the187 *		  first one is young.188 * @any_dirty: Optional pointer to indicate whether any entry except the189 *		  first one is dirty.190 *191 * Detect a PTE batch: consecutive (present) PTEs that map consecutive192 * pages of the same large folio.193 *194 * All PTEs inside a PTE batch have the same PTE bits set, excluding the PFN,195 * the accessed bit, writable bit, dirty bit (with FPB_IGNORE_DIRTY) and196 * soft-dirty bit (with FPB_IGNORE_SOFT_DIRTY).197 *198 * start_ptep must map any page of the folio. max_nr must be at least one and199 * must be limited by the caller so scanning cannot exceed a single page table.200 *201 * Return: the number of table entries in the batch.202 */203static inline int folio_pte_batch(struct folio *folio, unsigned long addr,204		pte_t *start_ptep, pte_t pte, int max_nr, fpb_t flags,205		bool *any_writable, bool *any_young, bool *any_dirty)206{207	unsigned long folio_end_pfn = folio_pfn(folio) + folio_nr_pages(folio);208	const pte_t *end_ptep = start_ptep + max_nr;209	pte_t expected_pte, *ptep;210	bool writable, young, dirty;211	int nr;212 213	if (any_writable)214		*any_writable = false;215	if (any_young)216		*any_young = false;217	if (any_dirty)218		*any_dirty = false;219 220	VM_WARN_ON_FOLIO(!pte_present(pte), folio);221	VM_WARN_ON_FOLIO(!folio_test_large(folio) || max_nr < 1, folio);222	VM_WARN_ON_FOLIO(page_folio(pfn_to_page(pte_pfn(pte))) != folio, folio);223 224	nr = pte_batch_hint(start_ptep, pte);225	expected_pte = __pte_batch_clear_ignored(pte_advance_pfn(pte, nr), flags);226	ptep = start_ptep + nr;227 228	while (ptep < end_ptep) {229		pte = ptep_get(ptep);230		if (any_writable)231			writable = !!pte_write(pte);232		if (any_young)233			young = !!pte_young(pte);234		if (any_dirty)235			dirty = !!pte_dirty(pte);236		pte = __pte_batch_clear_ignored(pte, flags);237 238		if (!pte_same(pte, expected_pte))239			break;240 241		/*242		 * Stop immediately once we reached the end of the folio. In243		 * corner cases the next PFN might fall into a different244		 * folio.245		 */246		if (pte_pfn(pte) >= folio_end_pfn)247			break;248 249		if (any_writable)250			*any_writable |= writable;251		if (any_young)252			*any_young |= young;253		if (any_dirty)254			*any_dirty |= dirty;255 256		nr = pte_batch_hint(ptep, pte);257		expected_pte = pte_advance_pfn(expected_pte, nr);258		ptep += nr;259	}260 261	return min(ptep - start_ptep, max_nr);262}263 264/**265 * pte_move_swp_offset - Move the swap entry offset field of a swap pte266 *	 forward or backward by delta267 * @pte: The initial pte state; is_swap_pte(pte) must be true and268 *	 non_swap_entry() must be false.269 * @delta: The direction and the offset we are moving; forward if delta270 *	 is positive; backward if delta is negative271 *272 * Moves the swap offset, while maintaining all other fields, including273 * swap type, and any swp pte bits. The resulting pte is returned.274 */275static inline pte_t pte_move_swp_offset(pte_t pte, long delta)276{277	swp_entry_t entry = pte_to_swp_entry(pte);278	pte_t new = __swp_entry_to_pte(__swp_entry(swp_type(entry),279						   (swp_offset(entry) + delta)));280 281	if (pte_swp_soft_dirty(pte))282		new = pte_swp_mksoft_dirty(new);283	if (pte_swp_exclusive(pte))284		new = pte_swp_mkexclusive(new);285	if (pte_swp_uffd_wp(pte))286		new = pte_swp_mkuffd_wp(new);287 288	return new;289}290 291 292/**293 * pte_next_swp_offset - Increment the swap entry offset field of a swap pte.294 * @pte: The initial pte state; is_swap_pte(pte) must be true and295 *	 non_swap_entry() must be false.296 *297 * Increments the swap offset, while maintaining all other fields, including298 * swap type, and any swp pte bits. The resulting pte is returned.299 */300static inline pte_t pte_next_swp_offset(pte_t pte)301{302	return pte_move_swp_offset(pte, 1);303}304 305/**306 * swap_pte_batch - detect a PTE batch for a set of contiguous swap entries307 * @start_ptep: Page table pointer for the first entry.308 * @max_nr: The maximum number of table entries to consider.309 * @pte: Page table entry for the first entry.310 *311 * Detect a batch of contiguous swap entries: consecutive (non-present) PTEs312 * containing swap entries all with consecutive offsets and targeting the same313 * swap type, all with matching swp pte bits.314 *315 * max_nr must be at least one and must be limited by the caller so scanning316 * cannot exceed a single page table.317 *318 * Return: the number of table entries in the batch.319 */320static inline int swap_pte_batch(pte_t *start_ptep, int max_nr, pte_t pte)321{322	pte_t expected_pte = pte_next_swp_offset(pte);323	const pte_t *end_ptep = start_ptep + max_nr;324	swp_entry_t entry = pte_to_swp_entry(pte);325	pte_t *ptep = start_ptep + 1;326	unsigned short cgroup_id;327 328	VM_WARN_ON(max_nr < 1);329	VM_WARN_ON(!is_swap_pte(pte));330	VM_WARN_ON(non_swap_entry(entry));331 332	cgroup_id = lookup_swap_cgroup_id(entry);333	while (ptep < end_ptep) {334		pte = ptep_get(ptep);335 336		if (!pte_same(pte, expected_pte))337			break;338		if (lookup_swap_cgroup_id(pte_to_swp_entry(pte)) != cgroup_id)339			break;340		expected_pte = pte_next_swp_offset(expected_pte);341		ptep++;342	}343 344	return ptep - start_ptep;345}346#endif /* CONFIG_MMU */347 348void __acct_reclaim_writeback(pg_data_t *pgdat, struct folio *folio,349						int nr_throttled);350static inline void acct_reclaim_writeback(struct folio *folio)351{352	pg_data_t *pgdat = folio_pgdat(folio);353	int nr_throttled = atomic_read(&pgdat->nr_writeback_throttled);354 355	if (nr_throttled)356		__acct_reclaim_writeback(pgdat, folio, nr_throttled);357}358 359static inline void wake_throttle_isolated(pg_data_t *pgdat)360{361	wait_queue_head_t *wqh;362 363	wqh = &pgdat->reclaim_wait[VMSCAN_THROTTLE_ISOLATED];364	if (waitqueue_active(wqh))365		wake_up(wqh);366}367 368vm_fault_t __vmf_anon_prepare(struct vm_fault *vmf) HWJS_SUSPENDS;369static inline vm_fault_t vmf_anon_prepare(struct vm_fault *vmf)370{371	vm_fault_t ret = __vmf_anon_prepare(vmf);372 373	if (unlikely(ret & VM_FAULT_RETRY))374		vma_end_read(vmf->vma);375	return ret;376}377 378vm_fault_t do_swap_page(struct vm_fault *vmf) HWJS_SUSPENDS;379void folio_rotate_reclaimable(struct folio *folio);380bool __folio_end_writeback(struct folio *folio) HWJS_SUSPENDS;381void deactivate_file_folio(struct folio *folio);382void folio_activate(struct folio *folio);383 384void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas,385		   struct vm_area_struct *start_vma, unsigned long floor,386		   unsigned long ceiling, bool mm_wr_locked) HWJS_SUSPENDS;387void pmd_install(struct mm_struct *mm, pmd_t *pmd, pgtable_t *pte);388 389struct zap_details;390void unmap_page_range(struct mmu_gather *tlb,391			     struct vm_area_struct *vma,392			     unsigned long addr, unsigned long end,393			     struct zap_details *details) HWJS_SUSPENDS;394 395void page_cache_ra_order(struct readahead_control *, struct file_ra_state *,396		unsigned int order) HWJS_SUSPENDS;397void force_page_cache_ra(struct readahead_control *, unsigned long nr) HWJS_SUSPENDS;398static inline void force_page_cache_readahead(struct address_space *mapping,399		struct file *file, pgoff_t index, unsigned long nr_to_read)400{401	DEFINE_READAHEAD(ractl, file, &file->f_ra, mapping, index);402	force_page_cache_ra(&ractl, nr_to_read);403}404 405unsigned find_lock_entries(struct address_space *mapping, pgoff_t *start,406		pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices) HWJS_SUSPENDS;407unsigned find_get_entries(struct address_space *mapping, pgoff_t *start,408		pgoff_t end, struct folio_batch *fbatch, pgoff_t *indices);409void filemap_free_folio(struct address_space *mapping, struct folio *folio) HWJS_SUSPENDS;410int truncate_inode_folio(struct address_space *mapping, struct folio *folio);411bool truncate_inode_partial_folio(struct folio *folio, loff_t start,412		loff_t end);413long mapping_evict_folio(struct address_space *mapping, struct folio *folio);414unsigned long mapping_try_invalidate(struct address_space *mapping,415		pgoff_t start, pgoff_t end, unsigned long *nr_failed) HWJS_SUSPENDS;416 417/**418 * folio_evictable - Test whether a folio is evictable.419 * @folio: The folio to test.420 *421 * Test whether @folio is evictable -- i.e., should be placed on422 * active/inactive lists vs unevictable list.423 *424 * Reasons folio might not be evictable:425 * 1. folio's mapping marked unevictable426 * 2. One of the pages in the folio is part of an mlocked VMA427 */428static inline bool folio_evictable(struct folio *folio)429{430	bool ret;431 432	/* Prevent address_space of inode and swap cache from being freed */433	rcu_read_lock();434	ret = !mapping_unevictable(folio_mapping(folio)) &&435			!folio_test_mlocked(folio);436	rcu_read_unlock();437	return ret;438}439 440/*441 * Turn a non-refcounted page (->_refcount == 0) into refcounted with442 * a count of one.443 */444static inline void set_page_refcounted(struct page *page)445{446	VM_BUG_ON_PAGE(PageTail(page), page);447	VM_BUG_ON_PAGE(page_ref_count(page), page);448	set_page_count(page, 1);449}450 451/*452 * Return true if a folio needs ->release_folio() calling upon it.453 */454static inline bool folio_needs_release(struct folio *folio)455{456	struct address_space *mapping = folio_mapping(folio);457 458	return folio_has_private(folio) ||459		(mapping && mapping_release_always(mapping));460}461 462extern unsigned long highest_memmap_pfn;463 464/*465 * Maximum number of reclaim retries without progress before the OOM466 * killer is consider the only way forward.467 */468#define MAX_RECLAIM_RETRIES 16469 470/*471 * in mm/vmscan.c:472 */473bool folio_isolate_lru(struct folio *folio);474void folio_putback_lru(struct folio *folio);475extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason) HWJS_SUSPENDS;476 477/*478 * in mm/rmap.c:479 */480pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address);481 482/*483 * in mm/page_alloc.c484 */485#define K(x) ((x) << (PAGE_SHIFT-10))486 487extern char * const zone_names[MAX_NR_ZONES];488 489/* perform sanity checks on struct pages being allocated or freed */490DECLARE_STATIC_KEY_MAYBE(CONFIG_DEBUG_VM, check_pages_enabled);491 492extern int min_free_kbytes;493 494void setup_per_zone_wmarks(void) HWJS_SUSPENDS;495void calculate_min_free_kbytes(void);496int __meminit init_per_zone_wmark_min(void) HWJS_SUSPENDS;497void page_alloc_sysctl_init(void);498 499/*500 * Structure for holding the mostly immutable allocation parameters passed501 * between functions involved in allocations, including the alloc_pages*502 * family of functions.503 *504 * nodemask, migratetype and highest_zoneidx are initialized only once in505 * __alloc_pages() and then never change.506 *507 * zonelist, preferred_zone and highest_zoneidx are set first in508 * __alloc_pages() for the fast path, and might be later changed509 * in __alloc_pages_slowpath(). All other functions pass the whole structure510 * by a const pointer.511 */512struct alloc_context {513	struct zonelist *zonelist;514	nodemask_t *nodemask;515	struct zoneref *preferred_zoneref;516	int migratetype;517 518	/*519	 * highest_zoneidx represents highest usable zone index of520	 * the allocation request. Due to the nature of the zone,521	 * memory on lower zone than the highest_zoneidx will be522	 * protected by lowmem_reserve[highest_zoneidx].523	 *524	 * highest_zoneidx is also used by reclaim/compaction to limit525	 * the target zone since higher zone than this index cannot be526	 * usable for this allocation request.527	 */528	enum zone_type highest_zoneidx;529	bool spread_dirty_pages;530};531 532/*533 * This function returns the order of a free page in the buddy system. In534 * general, page_zone(page)->lock must be held by the caller to prevent the535 * page from being allocated in parallel and returning garbage as the order.536 * If a caller does not hold page_zone(page)->lock, it must guarantee that the537 * page cannot be allocated or merged in parallel. Alternatively, it must538 * handle invalid values gracefully, and use buddy_order_unsafe() below.539 */540static inline unsigned int buddy_order(struct page *page)541{542	/* PageBuddy() must be checked by the caller */543	return page_private(page);544}545 546/*547 * Like buddy_order(), but for callers who cannot afford to hold the zone lock.548 * PageBuddy() should be checked first by the caller to minimize race window,549 * and invalid values must be handled gracefully.550 *551 * READ_ONCE is used so that if the caller assigns the result into a local552 * variable and e.g. tests it for valid range before using, the compiler cannot553 * decide to remove the variable and inline the page_private(page) multiple554 * times, potentially observing different values in the tests and the actual555 * use of the result.556 */557#define buddy_order_unsafe(page)	READ_ONCE(page_private(page))558 559/*560 * This function checks whether a page is free && is the buddy561 * we can coalesce a page and its buddy if562 * (a) the buddy is not in a hole (check before calling!) &&563 * (b) the buddy is in the buddy system &&564 * (c) a page and its buddy have the same order &&565 * (d) a page and its buddy are in the same zone.566 *567 * For recording whether a page is in the buddy system, we set PageBuddy.568 * Setting, clearing, and testing PageBuddy is serialized by zone->lock.569 *570 * For recording page's order, we use page_private(page).571 */572static inline bool page_is_buddy(struct page *page, struct page *buddy,573				 unsigned int order)574{575	if (!page_is_guard(buddy) && !PageBuddy(buddy))576		return false;577 578	if (buddy_order(buddy) != order)579		return false;580 581	/*582	 * zone check is done late to avoid uselessly calculating583	 * zone/node ids for pages that could never merge.584	 */585	if (page_zone_id(page) != page_zone_id(buddy))586		return false;587 588	VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy);589 590	return true;591}592 593/*594 * Locate the struct page for both the matching buddy in our595 * pair (buddy1) and the combined O(n+1) page they form (page).596 *597 * 1) Any buddy B1 will have an order O twin B2 which satisfies598 * the following equation:599 *     B2 = B1 ^ (1 << O)600 * For example, if the starting buddy (buddy2) is #8 its order601 * 1 buddy is #10:602 *     B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10603 *604 * 2) Any buddy B will have an order O+1 parent P which605 * satisfies the following equation:606 *     P = B & ~(1 << O)607 *608 * Assumption: *_mem_map is contiguous at least up to MAX_PAGE_ORDER609 */610static inline unsigned long611__find_buddy_pfn(unsigned long page_pfn, unsigned int order)612{613	return page_pfn ^ (1 << order);614}615 616/*617 * Find the buddy of @page and validate it.618 * @page: The input page619 * @pfn: The pfn of the page, it saves a call to page_to_pfn() when the620 *       function is used in the performance-critical __free_one_page().621 * @order: The order of the page622 * @buddy_pfn: The output pointer to the buddy pfn, it also saves a call to623 *             page_to_pfn().624 *625 * The found buddy can be a non PageBuddy, out of @page's zone, or its order is626 * not the same as @page. The validation is necessary before use it.627 *628 * Return: the found buddy page or NULL if not found.629 */630static inline struct page *find_buddy_page_pfn(struct page *page,631			unsigned long pfn, unsigned int order, unsigned long *buddy_pfn)632{633	unsigned long __buddy_pfn = __find_buddy_pfn(pfn, order);634	struct page *buddy;635 636	buddy = page + (__buddy_pfn - pfn);637	if (buddy_pfn)638		*buddy_pfn = __buddy_pfn;639 640	if (page_is_buddy(page, buddy, order))641		return buddy;642	return NULL;643}644 645extern struct page *__pageblock_pfn_to_page(unsigned long start_pfn,646				unsigned long end_pfn, struct zone *zone);647 648static inline struct page *pageblock_pfn_to_page(unsigned long start_pfn,649				unsigned long end_pfn, struct zone *zone)650{651	if (zone->contiguous)652		return pfn_to_page(start_pfn);653 654	return __pageblock_pfn_to_page(start_pfn, end_pfn, zone);655}656 657void set_zone_contiguous(struct zone *zone) HWJS_SUSPENDS;658 659static inline void clear_zone_contiguous(struct zone *zone)660{661	zone->contiguous = false;662}663 664extern int __isolate_free_page(struct page *page, unsigned int order);665extern void __putback_isolated_page(struct page *page, unsigned int order,666				    int mt);667extern void memblock_free_pages(struct page *page, unsigned long pfn,668					unsigned int order);669extern void __free_pages_core(struct page *page, unsigned int order,670		enum meminit_context context);671 672/*673 * This will have no effect, other than possibly generating a warning, if the674 * caller passes in a non-large folio.675 */676static inline void folio_set_order(struct folio *folio, unsigned int order)677{678	if (WARN_ON_ONCE(!order || !folio_test_large(folio)))679		return;680 681	folio->_flags_1 = (folio->_flags_1 & ~0xffUL) | order;682#ifdef CONFIG_64BIT683	folio->_folio_nr_pages = 1U << order;684#endif685}686 687bool __folio_unqueue_deferred_split(struct folio *folio);688static inline bool folio_unqueue_deferred_split(struct folio *folio)689{690	if (folio_order(folio) <= 1 || !folio_test_large_rmappable(folio))691		return false;692 693	/*694	 * At this point, there is no one trying to add the folio to695	 * deferred_list. If folio is not in deferred_list, it's safe696	 * to check without acquiring the split_queue_lock.697	 */698	if (data_race(list_empty(&folio->_deferred_list)))699		return false;700 701	return __folio_unqueue_deferred_split(folio);702}703 704static inline struct folio *page_rmappable_folio(struct page *page)705{706	struct folio *folio = (struct folio *)page;707 708	if (folio && folio_test_large(folio))709		folio_set_large_rmappable(folio);710	return folio;711}712 713static inline void prep_compound_head(struct page *page, unsigned int order)714{715	struct folio *folio = (struct folio *)page;716 717	folio_set_order(folio, order);718	atomic_set(&folio->_large_mapcount, -1);719	atomic_set(&folio->_entire_mapcount, -1);720	atomic_set(&folio->_nr_pages_mapped, 0);721	atomic_set(&folio->_pincount, 0);722	if (order > 1)723		INIT_LIST_HEAD(&folio->_deferred_list);724}725 726static inline void prep_compound_tail(struct page *head, int tail_idx)727{728	struct page *p = head + tail_idx;729 730	p->mapping = TAIL_MAPPING;731	set_compound_head(p, head);732	set_page_private(p, 0);733}734 735extern void prep_compound_page(struct page *page, unsigned int order);736 737extern void post_alloc_hook(struct page *page, unsigned int order,738					gfp_t gfp_flags);739extern bool free_pages_prepare(struct page *page, unsigned int order);740 741extern int user_min_free_kbytes;742 743void free_unref_page(struct page *page, unsigned int order);744void free_unref_folios(struct folio_batch *fbatch);745 746extern void zone_pcp_reset(struct zone *zone);747extern void zone_pcp_disable(struct zone *zone) HWJS_SUSPENDS;748extern void zone_pcp_enable(struct zone *zone) HWJS_SUSPENDS;749extern void zone_pcp_init(struct zone *zone);750 751extern void *memmap_alloc(phys_addr_t size, phys_addr_t align,752			  phys_addr_t min_addr,753			  int nid, bool exact_nid);754 755void memmap_init_range(unsigned long, int, unsigned long, unsigned long,756		unsigned long, enum meminit_context, struct vmem_altmap *, int) HWJS_SUSPENDS;757 758#if defined CONFIG_COMPACTION || defined CONFIG_CMA759 760/*761 * in mm/compaction.c762 */763/*764 * compact_control is used to track pages being migrated and the free pages765 * they are being migrated to during memory compaction. The free_pfn starts766 * at the end of a zone and migrate_pfn begins at the start. Movable pages767 * are moved to the end of a zone during a compaction run and the run768 * completes when free_pfn <= migrate_pfn769 */770struct compact_control {771	struct list_head freepages[NR_PAGE_ORDERS];	/* List of free pages to migrate to */772	struct list_head migratepages;	/* List of pages being migrated */773	unsigned int nr_freepages;	/* Number of isolated free pages */774	unsigned int nr_migratepages;	/* Number of pages to migrate */775	unsigned long free_pfn;		/* isolate_freepages search base */776	/*777	 * Acts as an in/out parameter to page isolation for migration.778	 * isolate_migratepages uses it as a search base.779	 * isolate_migratepages_block will update the value to the next pfn780	 * after the last isolated one.781	 */782	unsigned long migrate_pfn;783	unsigned long fast_start_pfn;	/* a pfn to start linear scan from */784	struct zone *zone;785	unsigned long total_migrate_scanned;786	unsigned long total_free_scanned;787	unsigned short fast_search_fail;/* failures to use free list searches */788	short search_order;		/* order to start a fast search at */789	const gfp_t gfp_mask;		/* gfp mask of a direct compactor */790	int order;			/* order a direct compactor needs */791	int migratetype;		/* migratetype of direct compactor */792	const unsigned int alloc_flags;	/* alloc flags of a direct compactor */793	const int highest_zoneidx;	/* zone index of a direct compactor */794	enum migrate_mode mode;		/* Async or sync migration mode */795	bool ignore_skip_hint;		/* Scan blocks even if marked skip */796	bool no_set_skip_hint;		/* Don't mark blocks for skipping */797	bool ignore_block_suitable;	/* Scan blocks considered unsuitable */798	bool direct_compaction;		/* False from kcompactd or /proc/... */799	bool proactive_compaction;	/* kcompactd proactive compaction */800	bool whole_zone;		/* Whole zone should/has been scanned */801	bool contended;			/* Signal lock contention */802	bool finish_pageblock;		/* Scan the remainder of a pageblock. Used803					 * when there are potentially transient804					 * isolation or migration failures to805					 * ensure forward progress.806					 */807	bool alloc_contig;		/* alloc_contig_range allocation */808};809 810/*811 * Used in direct compaction when a page should be taken from the freelists812 * immediately when one is created during the free path.813 */814struct capture_control {815	struct compact_control *cc;816	struct page *page;817};818 819unsigned long820isolate_freepages_range(struct compact_control *cc,821			unsigned long start_pfn, unsigned long end_pfn) HWJS_SUSPENDS;822int823isolate_migratepages_range(struct compact_control *cc,824			   unsigned long low_pfn, unsigned long end_pfn) HWJS_SUSPENDS;825 826int __alloc_contig_migrate_range(struct compact_control *cc,827					unsigned long start, unsigned long end,828					int migratetype);829 830/* Free whole pageblock and set its migration type to MIGRATE_CMA. */831void init_cma_reserved_pageblock(struct page *page);832 833#endif /* CONFIG_COMPACTION || CONFIG_CMA */834 835int find_suitable_fallback(struct free_area *area, unsigned int order,836			int migratetype, bool only_stealable, bool *can_steal);837 838static inline bool free_area_empty(struct free_area *area, int migratetype)839{840	return list_empty(&area->free_list[migratetype]);841}842 843/* mm/util.c */844struct anon_vma *folio_anon_vma(struct folio *folio);845 846#ifdef CONFIG_MMU847void unmap_mapping_folio(struct folio *folio);848extern long populate_vma_page_range(struct vm_area_struct *vma,849		unsigned long start, unsigned long end, int *locked) HWJS_SUSPENDS;850extern long faultin_page_range(struct mm_struct *mm, unsigned long start,851		unsigned long end, bool write, int *locked) HWJS_SUSPENDS;852extern bool mlock_future_ok(struct mm_struct *mm, unsigned long flags,853			       unsigned long bytes);854 855/*856 * NOTE: This function can't tell whether the folio is "fully mapped" in the857 * range.858 * "fully mapped" means all the pages of folio is associated with the page859 * table of range while this function just check whether the folio range is860 * within the range [start, end). Function caller needs to do page table861 * check if it cares about the page table association.862 *863 * Typical usage (like mlock or madvise) is:864 * Caller knows at least 1 page of folio is associated with page table of VMA865 * and the range [start, end) is intersect with the VMA range. Caller wants866 * to know whether the folio is fully associated with the range. It calls867 * this function to check whether the folio is in the range first. Then checks868 * the page table to know whether the folio is fully mapped to the range.869 */870static inline bool871folio_within_range(struct folio *folio, struct vm_area_struct *vma,872		unsigned long start, unsigned long end)873{874	pgoff_t pgoff, addr;875	unsigned long vma_pglen = vma_pages(vma);876 877	VM_WARN_ON_FOLIO(folio_test_ksm(folio), folio);878	if (start > end)879		return false;880 881	if (start < vma->vm_start)882		start = vma->vm_start;883 884	if (end > vma->vm_end)885		end = vma->vm_end;886 887	pgoff = folio_pgoff(folio);888 889	/* if folio start address is not in vma range */890	if (!in_range(pgoff, vma->vm_pgoff, vma_pglen))891		return false;892 893	addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);894 895	return !(addr < start || end - addr < folio_size(folio));896}897 898static inline bool899folio_within_vma(struct folio *folio, struct vm_area_struct *vma)900{901	return folio_within_range(folio, vma, vma->vm_start, vma->vm_end);902}903 904/*905 * mlock_vma_folio() and munlock_vma_folio():906 * should be called with vma's mmap_lock held for read or write,907 * under page table lock for the pte/pmd being added or removed.908 *909 * mlock is usually called at the end of folio_add_*_rmap_*(), munlock at910 * the end of folio_remove_rmap_*(); but new anon folios are managed by911 * folio_add_lru_vma() calling mlock_new_folio().912 */913void mlock_folio(struct folio *folio);914static inline void mlock_vma_folio(struct folio *folio,915				struct vm_area_struct *vma)916{917	/*918	 * The VM_SPECIAL check here serves two purposes.919	 * 1) VM_IO check prevents migration from double-counting during mlock.920	 * 2) Although mmap_region() and mlock_fixup() take care that VM_LOCKED921	 *    is never left set on a VM_SPECIAL vma, there is an interval while922	 *    file->f_op->mmap() is using vm_insert_page(s), when VM_LOCKED may923	 *    still be set while VM_SPECIAL bits are added: so ignore it then.924	 */925	if (unlikely((vma->vm_flags & (VM_LOCKED|VM_SPECIAL)) == VM_LOCKED))926		mlock_folio(folio);927}928 929void munlock_folio(struct folio *folio);930static inline void munlock_vma_folio(struct folio *folio,931					struct vm_area_struct *vma)932{933	/*934	 * munlock if the function is called. Ideally, we should only935	 * do munlock if any page of folio is unmapped from VMA and936	 * cause folio not fully mapped to VMA.937	 *938	 * But it's not easy to confirm that's the situation. So we939	 * always munlock the folio and page reclaim will correct it940	 * if it's wrong.941	 */942	if (unlikely(vma->vm_flags & VM_LOCKED))943		munlock_folio(folio);944}945 946void mlock_new_folio(struct folio *folio);947bool need_mlock_drain(int cpu);948void mlock_drain_local(void);949void mlock_drain_remote(int cpu);950 951extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma);952 953/**954 * vma_address - Find the virtual address a page range is mapped at955 * @vma: The vma which maps this object.956 * @pgoff: The page offset within its object.957 * @nr_pages: The number of pages to consider.958 *959 * If any page in this range is mapped by this VMA, return the first address960 * where any of these pages appear.  Otherwise, return -EFAULT.961 */962static inline unsigned long vma_address(struct vm_area_struct *vma,963		pgoff_t pgoff, unsigned long nr_pages)964{965	unsigned long address;966 967	if (pgoff >= vma->vm_pgoff) {968		address = vma->vm_start +969			((pgoff - vma->vm_pgoff) << PAGE_SHIFT);970		/* Check for address beyond vma (or wrapped through 0?) */971		if (address < vma->vm_start || address >= vma->vm_end)972			address = -EFAULT;973	} else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) {974		/* Test above avoids possibility of wrap to 0 on 32-bit */975		address = vma->vm_start;976	} else {977		address = -EFAULT;978	}979	return address;980}981 982/*983 * Then at what user virtual address will none of the range be found in vma?984 * Assumes that vma_address() already returned a good starting address.985 */986static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw)987{988	struct vm_area_struct *vma = pvmw->vma;989	pgoff_t pgoff;990	unsigned long address;991 992	/* Common case, plus ->pgoff is invalid for KSM */993	if (pvmw->nr_pages == 1)994		return pvmw->address + PAGE_SIZE;995 996	pgoff = pvmw->pgoff + pvmw->nr_pages;997	address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);998	/* Check for address beyond vma (or wrapped through 0?) */999	if (address < vma->vm_start || address > vma->vm_end)1000		address = vma->vm_end;1001	return address;1002}1003 1004static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf,1005						    struct file *fpin)1006{1007	int flags = vmf->flags;1008 1009	if (fpin)1010		return fpin;1011 1012	/*1013	 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or1014	 * anything, so we only pin the file and drop the mmap_lock if only1015	 * FAULT_FLAG_ALLOW_RETRY is set, while this is the first attempt.1016	 */1017	if (fault_flag_allow_retry_first(flags) &&1018	    !(flags & FAULT_FLAG_RETRY_NOWAIT)) {1019		fpin = get_file(vmf->vma->vm_file);1020		release_fault_lock(vmf);1021	}1022	return fpin;1023}1024#else /* !CONFIG_MMU */1025static inline void unmap_mapping_folio(struct folio *folio) { }1026static inline void mlock_new_folio(struct folio *folio) { }1027static inline bool need_mlock_drain(int cpu) { return false; }1028static inline void mlock_drain_local(void) { }1029static inline void mlock_drain_remote(int cpu) { }1030static inline void vunmap_range_noflush(unsigned long start, unsigned long end)1031{1032}1033#endif /* !CONFIG_MMU */1034 1035/* Memory initialisation debug and verification */1036#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT1037DECLARE_STATIC_KEY_TRUE(deferred_pages);1038 1039bool __init deferred_grow_zone(struct zone *zone, unsigned int order);1040#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */1041 1042enum mminit_level {1043	MMINIT_WARNING,1044	MMINIT_VERIFY,1045	MMINIT_TRACE1046};1047 1048#ifdef CONFIG_DEBUG_MEMORY_INIT1049 1050extern int mminit_loglevel;1051 1052#define mminit_dprintk(level, prefix, fmt, arg...) \1053do { \1054	if (level < mminit_loglevel) { \1055		if (level <= MMINIT_WARNING) \1056			pr_warn("mminit::" prefix " " fmt, ##arg);	\1057		else \1058			printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \1059	} \1060} while (0)1061 1062extern void mminit_verify_pageflags_layout(void);1063extern void mminit_verify_zonelist(void);1064#else1065 1066static inline void mminit_dprintk(enum mminit_level level,1067				const char *prefix, const char *fmt, ...)1068{1069}1070 1071static inline void mminit_verify_pageflags_layout(void)1072{1073}1074 1075static inline void mminit_verify_zonelist(void)1076{1077}1078#endif /* CONFIG_DEBUG_MEMORY_INIT */1079 1080#define NODE_RECLAIM_NOSCAN	-21081#define NODE_RECLAIM_FULL	-11082#define NODE_RECLAIM_SOME	01083#define NODE_RECLAIM_SUCCESS	11084 1085#ifdef CONFIG_NUMA1086extern int node_reclaim(struct pglist_data *, gfp_t, unsigned int);1087extern int find_next_best_node(int node, nodemask_t *used_node_mask);1088#else1089static inline int node_reclaim(struct pglist_data *pgdat, gfp_t mask,1090				unsigned int order)1091{1092	return NODE_RECLAIM_NOSCAN;1093}1094static inline int find_next_best_node(int node, nodemask_t *used_node_mask)1095{1096	return NUMA_NO_NODE;1097}1098#endif1099 1100/*1101 * mm/memory-failure.c1102 */1103#ifdef CONFIG_MEMORY_FAILURE1104void unmap_poisoned_folio(struct folio *folio, enum ttu_flags ttu);1105void shake_folio(struct folio *folio);1106extern int hwpoison_filter(struct page *p);1107 1108extern u32 hwpoison_filter_dev_major;1109extern u32 hwpoison_filter_dev_minor;1110extern u64 hwpoison_filter_flags_mask;1111extern u64 hwpoison_filter_flags_value;1112extern u64 hwpoison_filter_memcg;1113extern u32 hwpoison_filter_enable;1114#define MAGIC_HWPOISON	0x48575053U	/* HWPS */1115void SetPageHWPoisonTakenOff(struct page *page);1116void ClearPageHWPoisonTakenOff(struct page *page);1117bool take_page_off_buddy(struct page *page);1118bool put_page_back_buddy(struct page *page);1119struct task_struct *task_early_kill(struct task_struct *tsk, int force_early);1120void add_to_kill_ksm(struct task_struct *tsk, struct page *p,1121		     struct vm_area_struct *vma, struct list_head *to_kill,1122		     unsigned long ksm_addr);1123unsigned long page_mapped_in_vma(struct page *page, struct vm_area_struct *vma);1124 1125#else1126static inline void unmap_poisoned_folio(struct folio *folio, enum ttu_flags ttu)1127{1128}1129#endif1130 1131extern unsigned long  __must_check vm_mmap_pgoff(struct file *, unsigned long,1132        unsigned long, unsigned long,1133        unsigned long, unsigned long);1134 1135extern void set_pageblock_order(void);1136struct folio *alloc_migrate_folio(struct folio *src, unsigned long private);1137unsigned long reclaim_pages(struct list_head *folio_list) HWJS_SUSPENDS;1138unsigned int reclaim_clean_pages_from_list(struct zone *zone,1139					    struct list_head *folio_list) HWJS_SUSPENDS;1140/* The ALLOC_WMARK bits are used as an index to zone->watermark */1141#define ALLOC_WMARK_MIN		WMARK_MIN1142#define ALLOC_WMARK_LOW		WMARK_LOW1143#define ALLOC_WMARK_HIGH	WMARK_HIGH1144#define ALLOC_NO_WATERMARKS	0x04 /* don't check watermarks at all */1145 1146/* Mask to get the watermark bits */1147#define ALLOC_WMARK_MASK	(ALLOC_NO_WATERMARKS-1)1148 1149/*1150 * Only MMU archs have async oom victim reclaim - aka oom_reaper so we1151 * cannot assume a reduced access to memory reserves is sufficient for1152 * !MMU1153 */1154#ifdef CONFIG_MMU1155#define ALLOC_OOM		0x081156#else1157#define ALLOC_OOM		ALLOC_NO_WATERMARKS1158#endif1159 1160#define ALLOC_NON_BLOCK		 0x10 /* Caller cannot block. Allow access1161				       * to 25% of the min watermark or1162				       * 62.5% if __GFP_HIGH is set.1163				       */1164#define ALLOC_MIN_RESERVE	 0x20 /* __GFP_HIGH set. Allow access to 50%1165				       * of the min watermark.1166				       */1167#define ALLOC_CPUSET		 0x40 /* check for correct cpuset */1168#define ALLOC_CMA		 0x80 /* allow allocations from CMA areas */1169#ifdef CONFIG_ZONE_DMA321170#define ALLOC_NOFRAGMENT	0x100 /* avoid mixing pageblock types */1171#else1172#define ALLOC_NOFRAGMENT	  0x01173#endif1174#define ALLOC_HIGHATOMIC	0x200 /* Allows access to MIGRATE_HIGHATOMIC */1175#define ALLOC_KSWAPD		0x800 /* allow waking of kswapd, __GFP_KSWAPD_RECLAIM set */1176 1177/* Flags that allow allocations below the min watermark. */1178#define ALLOC_RESERVES (ALLOC_NON_BLOCK|ALLOC_MIN_RESERVE|ALLOC_HIGHATOMIC|ALLOC_OOM)1179 1180enum ttu_flags;1181struct tlbflush_unmap_batch;1182 1183 1184/*1185 * only for MM internal work items which do not depend on1186 * any allocations or locks which might depend on allocations1187 */1188extern struct workqueue_struct *mm_percpu_wq;1189 1190#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH1191void try_to_unmap_flush(void);1192void try_to_unmap_flush_dirty(void);1193void flush_tlb_batched_pending(struct mm_struct *mm);1194#else1195static inline void try_to_unmap_flush(void)1196{1197}1198static inline void try_to_unmap_flush_dirty(void)1199{1200}1201static inline void flush_tlb_batched_pending(struct mm_struct *mm)1202{1203}1204#endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */1205 1206extern const struct trace_print_flags pageflag_names[];1207extern const struct trace_print_flags vmaflag_names[];1208extern const struct trace_print_flags gfpflag_names[];1209 1210static inline bool is_migrate_highatomic(enum migratetype migratetype)1211{1212	return migratetype == MIGRATE_HIGHATOMIC;1213}1214 1215void setup_zone_pageset(struct zone *zone);1216 1217struct migration_target_control {1218	int nid;		/* preferred node id */1219	nodemask_t *nmask;1220	gfp_t gfp_mask;1221	enum migrate_reason reason;1222};1223 1224/*1225 * mm/filemap.c1226 */1227size_t splice_folio_into_pipe(struct pipe_inode_info *pipe,1228			      struct folio *folio, loff_t fpos, size_t size);1229 1230/*1231 * mm/vmalloc.c1232 */1233#ifdef CONFIG_MMU1234void __init vmalloc_init(void);1235int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end,1236                pgprot_t prot, struct page **pages, unsigned int page_shift);1237#else1238static inline void vmalloc_init(void)1239{1240}1241 1242static inline1243int __must_check vmap_pages_range_noflush(unsigned long addr, unsigned long end,1244                pgprot_t prot, struct page **pages, unsigned int page_shift)1245{1246	return -EINVAL;1247}1248#endif1249 1250int __must_check __vmap_pages_range_noflush(unsigned long addr,1251			       unsigned long end, pgprot_t prot,1252			       struct page **pages, unsigned int page_shift);1253 1254void vunmap_range_noflush(unsigned long start, unsigned long end) HWJS_SUSPENDS;1255 1256void __vunmap_range_noflush(unsigned long start, unsigned long end) HWJS_SUSPENDS;1257 1258int numa_migrate_check(struct folio *folio, struct vm_fault *vmf,1259		      unsigned long addr, int *flags, bool writable,1260		      int *last_cpupid);1261 1262void free_zone_device_folio(struct folio *folio);1263int migrate_device_coherent_folio(struct folio *folio);1264 1265/*1266 * mm/gup.c1267 */1268int __must_check try_grab_folio(struct folio *folio, int refs,1269				unsigned int flags);1270 1271/*1272 * mm/huge_memory.c1273 */1274void touch_pud(struct vm_area_struct *vma, unsigned long addr,1275	       pud_t *pud, bool write);1276void touch_pmd(struct vm_area_struct *vma, unsigned long addr,1277	       pmd_t *pmd, bool write);1278 1279enum {1280	/* mark page accessed */1281	FOLL_TOUCH = 1 << 16,1282	/* a retry, previous pass started an IO */1283	FOLL_TRIED = 1 << 17,1284	/* we are working on non-current tsk/mm */1285	FOLL_REMOTE = 1 << 18,1286	/* pages must be released via unpin_user_page */1287	FOLL_PIN = 1 << 19,1288	/* gup_fast: prevent fall-back to slow gup */1289	FOLL_FAST_ONLY = 1 << 20,1290	/* allow unlocking the mmap lock */1291	FOLL_UNLOCKABLE = 1 << 21,1292	/* VMA lookup+checks compatible with MADV_POPULATE_(READ|WRITE) */1293	FOLL_MADV_POPULATE = 1 << 22,1294};1295 1296#define INTERNAL_GUP_FLAGS (FOLL_TOUCH | FOLL_TRIED | FOLL_REMOTE | FOLL_PIN | \1297			    FOLL_FAST_ONLY | FOLL_UNLOCKABLE | \1298			    FOLL_MADV_POPULATE)1299 1300/*1301 * Indicates for which pages that are write-protected in the page table,1302 * whether GUP has to trigger unsharing via FAULT_FLAG_UNSHARE such that the1303 * GUP pin will remain consistent with the pages mapped into the page tables1304 * of the MM.1305 *1306 * Temporary unmapping of PageAnonExclusive() pages or clearing of1307 * PageAnonExclusive() has to protect against concurrent GUP:1308 * * Ordinary GUP: Using the PT lock1309 * * GUP-fast and fork(): mm->write_protect_seq1310 * * GUP-fast and KSM or temporary unmapping (swap, migration): see1311 *    folio_try_share_anon_rmap_*()1312 *1313 * Must be called with the (sub)page that's actually referenced via the1314 * page table entry, which might not necessarily be the head page for a1315 * PTE-mapped THP.1316 *1317 * If the vma is NULL, we're coming from the GUP-fast path and might have1318 * to fallback to the slow path just to lookup the vma.1319 */1320static inline bool gup_must_unshare(struct vm_area_struct *vma,1321				    unsigned int flags, struct page *page)1322{1323	/*1324	 * FOLL_WRITE is implicitly handled correctly as the page table entry1325	 * has to be writable -- and if it references (part of) an anonymous1326	 * folio, that part is required to be marked exclusive.1327	 */1328	if ((flags & (FOLL_WRITE | FOLL_PIN)) != FOLL_PIN)1329		return false;1330	/*1331	 * Note: PageAnon(page) is stable until the page is actually getting1332	 * freed.1333	 */1334	if (!PageAnon(page)) {1335		/*1336		 * We only care about R/O long-term pining: R/O short-term1337		 * pinning does not have the semantics to observe successive1338		 * changes through the process page tables.1339		 */1340		if (!(flags & FOLL_LONGTERM))1341			return false;1342 1343		/* We really need the vma ... */1344		if (!vma)1345			return true;1346 1347		/*1348		 * ... because we only care about writable private ("COW")1349		 * mappings where we have to break COW early.1350		 */1351		return is_cow_mapping(vma->vm_flags);1352	}1353 1354	/* Paired with a memory barrier in folio_try_share_anon_rmap_*(). */1355	if (IS_ENABLED(CONFIG_HAVE_GUP_FAST))1356		smp_rmb();1357 1358	/*1359	 * Note that PageKsm() pages cannot be exclusive, and consequently,1360	 * cannot get pinned.1361	 */1362	return !PageAnonExclusive(page);1363}1364 1365extern bool mirrored_kernelcore;1366extern bool memblock_has_mirror(void);1367 1368static __always_inline void vma_set_range(struct vm_area_struct *vma,1369					  unsigned long start, unsigned long end,1370					  pgoff_t pgoff)1371{1372	vma->vm_start = start;1373	vma->vm_end = end;1374	vma->vm_pgoff = pgoff;1375}1376 1377static inline bool vma_soft_dirty_enabled(struct vm_area_struct *vma)1378{1379	/*1380	 * NOTE: we must check this before VM_SOFTDIRTY on soft-dirty1381	 * enablements, because when without soft-dirty being compiled in,1382	 * VM_SOFTDIRTY is defined as 0x0, then !(vm_flags & VM_SOFTDIRTY)1383	 * will be constantly true.1384	 */1385	if (!IS_ENABLED(CONFIG_MEM_SOFT_DIRTY))1386		return false;1387 1388	/*1389	 * Soft-dirty is kind of special: its tracking is enabled when the1390	 * vma flags not set.1391	 */1392	return !(vma->vm_flags & VM_SOFTDIRTY);1393}1394 1395static inline bool pmd_needs_soft_dirty_wp(struct vm_area_struct *vma, pmd_t pmd)1396{1397	return vma_soft_dirty_enabled(vma) && !pmd_soft_dirty(pmd);1398}1399 1400static inline bool pte_needs_soft_dirty_wp(struct vm_area_struct *vma, pte_t pte)1401{1402	return vma_soft_dirty_enabled(vma) && !pte_soft_dirty(pte);1403}1404 1405void __meminit __init_single_page(struct page *page, unsigned long pfn,1406				unsigned long zone, int nid);1407 1408/* shrinker related functions */1409unsigned long shrink_slab(gfp_t gfp_mask, int nid, struct mem_cgroup *memcg,1410			  int priority) HWJS_SUSPENDS;1411 1412#ifdef CONFIG_64BIT1413static inline int can_do_mseal(unsigned long flags)1414{1415	if (flags)1416		return -EINVAL;1417 1418	return 0;1419}1420 1421#else1422static inline int can_do_mseal(unsigned long flags)1423{1424	return -EPERM;1425}1426#endif1427 1428#ifdef CONFIG_SHRINKER_DEBUG1429static inline __printf(2, 0) int shrinker_debugfs_name_alloc(1430			struct shrinker *shrinker, const char *fmt, va_list ap)1431{1432	shrinker->name = kvasprintf_const(GFP_KERNEL, fmt, ap);1433 1434	return shrinker->name ? 0 : -ENOMEM;1435}1436 1437static inline void shrinker_debugfs_name_free(struct shrinker *shrinker)1438{1439	kfree_const(shrinker->name);1440	shrinker->name = NULL;1441}1442 1443extern int shrinker_debugfs_add(struct shrinker *shrinker);1444extern struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker,1445					      int *debugfs_id);1446extern void shrinker_debugfs_remove(struct dentry *debugfs_entry,1447				    int debugfs_id);1448#else /* CONFIG_SHRINKER_DEBUG */1449static inline int shrinker_debugfs_add(struct shrinker *shrinker)1450{1451	return 0;1452}1453static inline int shrinker_debugfs_name_alloc(struct shrinker *shrinker,1454					      const char *fmt, va_list ap)1455{1456	return 0;1457}1458static inline void shrinker_debugfs_name_free(struct shrinker *shrinker)1459{1460}1461static inline struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker,1462						     int *debugfs_id)1463{1464	*debugfs_id = -1;1465	return NULL;1466}1467static inline void shrinker_debugfs_remove(struct dentry *debugfs_entry,1468					   int debugfs_id)1469{1470}1471#endif /* CONFIG_SHRINKER_DEBUG */1472 1473/* Only track the nodes of mappings with shadow entries */1474void workingset_update_node(struct xa_node *node);1475extern struct list_lru shadow_nodes;1476 1477/* mremap.c */1478unsigned long move_page_tables(struct vm_area_struct *vma,1479	unsigned long old_addr, struct vm_area_struct *new_vma,1480	unsigned long new_addr, unsigned long len,1481	bool need_rmap_locks, bool for_stack) HWJS_SUSPENDS;1482 1483#ifdef CONFIG_UNACCEPTED_MEMORY1484void accept_page(struct page *page);1485#else /* CONFIG_UNACCEPTED_MEMORY */1486static inline void accept_page(struct page *page)1487{1488}1489#endif /* CONFIG_UNACCEPTED_MEMORY */1490 1491#endif	/* __MM_INTERNAL_H */1492