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Diffstat (limited to 'mm/internal.h')
| -rw-r--r-- | mm/internal.h | 1751 |
1 files changed, 1545 insertions, 206 deletions
diff --git a/mm/internal.h b/mm/internal.h index 4390ac6c106e..e430da900430 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1,104 +1,864 @@ +/* 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) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. */ #ifndef __MM_INTERNAL_H #define __MM_INTERNAL_H +#include <linux/fs.h> +#include <linux/khugepaged.h> #include <linux/mm.h> +#include <linux/mm_inline.h> +#include <linux/pagemap.h> +#include <linux/pagewalk.h> +#include <linux/rmap.h> +#include <linux/swap.h> +#include <linux/leafops.h> +#include <linux/swap_cgroup.h> +#include <linux/tracepoint-defs.h> + +/* Internal core VMA manipulation functions. */ +#include "vma.h" + +struct folio_batch; + +/* + * Maintains state across a page table move. The operation assumes both source + * and destination VMAs already exist and are specified by the user. + * + * Partial moves are permitted, but the old and new ranges must both reside + * within a VMA. + * + * mmap lock must be held in write and VMA write locks must be held on any VMA + * that is visible. + * + * Use the PAGETABLE_MOVE() macro to initialise this struct. + * + * The old_addr and new_addr fields are updated as the page table move is + * executed. + * + * NOTE: The page table move is affected by reading from [old_addr, old_end), + * and old_addr may be updated for better page table alignment, so len_in + * represents the length of the range being copied as specified by the user. + */ +struct pagetable_move_control { + struct vm_area_struct *old; /* Source VMA. */ + struct vm_area_struct *new; /* Destination VMA. */ + unsigned long old_addr; /* Address from which the move begins. */ + unsigned long old_end; /* Exclusive address at which old range ends. */ + unsigned long new_addr; /* Address to move page tables to. */ + unsigned long len_in; /* Bytes to remap specified by user. */ + + bool need_rmap_locks; /* Do rmap locks need to be taken? */ + bool for_stack; /* Is this an early temp stack being moved? */ +}; + +#define PAGETABLE_MOVE(name, old_, new_, old_addr_, new_addr_, len_) \ + struct pagetable_move_control name = { \ + .old = old_, \ + .new = new_, \ + .old_addr = old_addr_, \ + .old_end = (old_addr_) + (len_), \ + .new_addr = new_addr_, \ + .len_in = len_, \ + } + +/* + * 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) -void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma, - unsigned long floor, unsigned long ceiling); +/* Do not use these with a slab allocator */ +#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK) -static inline void set_page_count(struct page *page, int v) +/* + * 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 ENTIRELY_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 ENTIRELY_MAPPED 0x800000 +#define FOLIO_PAGES_MAPPED (ENTIRELY_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. + * + * Don't use this function outside of debugging code. + */ +static inline int folio_nr_pages_mapped(const struct folio *folio) { - atomic_set(&page->_count, v); + if (IS_ENABLED(CONFIG_NO_PAGE_MAPCOUNT)) + return -1; + return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED; } /* - * Turn a non-refcounted page (->_count == 0) into refcounted with - * a count of one. + * Retrieve the first entry of a folio based on a provided entry within the + * folio. We cannot rely on folio->swap as there is no guarantee that it has + * been initialized. Used for calling arch_swap_restore() */ -static inline void set_page_refcounted(struct page *page) +static inline swp_entry_t folio_swap(swp_entry_t entry, + const struct folio *folio) { - VM_BUG_ON(PageTail(page)); - VM_BUG_ON(atomic_read(&page->_count)); - set_page_count(page, 1); + swp_entry_t swap = { + .val = ALIGN_DOWN(entry.val, folio_nr_pages(folio)), + }; + + return swap; } -static inline void __get_page_tail_foll(struct page *page, - bool get_page_head) +static inline void *folio_raw_mapping(const struct folio *folio) { + unsigned long mapping = (unsigned long)folio->mapping; + + return (void *)(mapping & ~FOLIO_MAPPING_FLAGS); +} + +/* + * This is a file-backed mapping, and is about to be memory mapped - invoke its + * mmap hook and safely handle error conditions. On error, VMA hooks will be + * mutated. + * + * @file: File which backs the mapping. + * @vma: VMA which we are mapping. + * + * Returns: 0 if success, error otherwise. + */ +static inline int mmap_file(struct file *file, struct vm_area_struct *vma) +{ + int err = vfs_mmap(file, vma); + + if (likely(!err)) + return 0; + /* - * If we're getting a tail page, the elevated page->_count is - * required only in the head page and we will elevate the head - * page->_count and tail page->_mapcount. - * - * We elevate page_tail->_mapcount for tail pages to force - * page_tail->_count to be zero at all times to avoid getting - * false positives from get_page_unless_zero() with - * speculative page access (like in - * page_cache_get_speculative()) on tail pages. + * OK, we tried to call the file hook for mmap(), but an error + * arose. The mapping is in an inconsistent state and we most not invoke + * any further hooks on it. */ - VM_BUG_ON(atomic_read(&page->first_page->_count) <= 0); - VM_BUG_ON(atomic_read(&page->_count) != 0); - VM_BUG_ON(page_mapcount(page) < 0); - if (get_page_head) - atomic_inc(&page->first_page->_count); - atomic_inc(&page->_mapcount); + vma->vm_ops = &vma_dummy_vm_ops; + + return err; } /* - * This is meant to be called as the FOLL_GET operation of - * follow_page() and it must be called while holding the proper PT - * lock while the pte (or pmd_trans_huge) is still mapping the page. + * If the VMA has a close hook then close it, and since closing it might leave + * it in an inconsistent state which makes the use of any hooks suspect, clear + * them down by installing dummy empty hooks. */ -static inline void get_page_foll(struct page *page) +static inline void vma_close(struct vm_area_struct *vma) { - if (unlikely(PageTail(page))) - /* - * This is safe only because - * __split_huge_page_refcount() can't run under - * get_page_foll() because we hold the proper PT lock. - */ - __get_page_tail_foll(page, true); - else { + if (vma->vm_ops && vma->vm_ops->close) { + vma->vm_ops->close(vma); + /* - * Getting a normal page or the head of a compound page - * requires to already have an elevated page->_count. + * The mapping is in an inconsistent state, and no further hooks + * may be invoked upon it. */ - VM_BUG_ON(atomic_read(&page->_count) <= 0); - atomic_inc(&page->_count); + vma->vm_ops = &vma_dummy_vm_ops; } } +#ifdef CONFIG_MMU + +/* Flags for folio_pte_batch(). */ +typedef int __bitwise fpb_t; + +/* Compare PTEs respecting the dirty bit. */ +#define FPB_RESPECT_DIRTY ((__force fpb_t)BIT(0)) + +/* Compare PTEs respecting the soft-dirty bit. */ +#define FPB_RESPECT_SOFT_DIRTY ((__force fpb_t)BIT(1)) + +/* Compare PTEs respecting the writable bit. */ +#define FPB_RESPECT_WRITE ((__force fpb_t)BIT(2)) + +/* + * Merge PTE write bits: if any PTE in the batch is writable, modify the + * PTE at @ptentp to be writable. + */ +#define FPB_MERGE_WRITE ((__force fpb_t)BIT(3)) + +/* + * Merge PTE young and dirty bits: if any PTE in the batch is young or dirty, + * modify the PTE at @ptentp to be young or dirty, respectively. + */ +#define FPB_MERGE_YOUNG_DIRTY ((__force fpb_t)BIT(4)) + +static inline pte_t __pte_batch_clear_ignored(pte_t pte, fpb_t flags) +{ + if (!(flags & FPB_RESPECT_DIRTY)) + pte = pte_mkclean(pte); + if (likely(!(flags & FPB_RESPECT_SOFT_DIRTY))) + pte = pte_clear_soft_dirty(pte); + if (likely(!(flags & FPB_RESPECT_WRITE))) + pte = pte_wrprotect(pte); + return pte_mkold(pte); +} + +/** + * folio_pte_batch_flags - detect a PTE batch for a large folio + * @folio: The large folio to detect a PTE batch for. + * @vma: The VMA. Only relevant with FPB_MERGE_WRITE, otherwise can be NULL. + * @ptep: Page table pointer for the first entry. + * @ptentp: Pointer to a COPY of the first page table entry whose flags this + * function updates based on @flags if appropriate. + * @max_nr: The maximum number of table entries to consider. + * @flags: Flags to modify the PTE batch semantics. + * + * Detect a PTE batch: consecutive (present) PTEs that map consecutive + * pages of the same large folio in a single VMA and a single page table. + * + * All PTEs inside a PTE batch have the same PTE bits set, excluding the PFN, + * the accessed bit, writable bit, dirty bit (unless FPB_RESPECT_DIRTY is set) + * and soft-dirty bit (unless FPB_RESPECT_SOFT_DIRTY is set). + * + * @ptep must map any page of the folio. max_nr must be at least one and + * must be limited by the caller so scanning cannot exceed a single VMA and + * a single page table. + * + * Depending on the FPB_MERGE_* flags, the pte stored at @ptentp will + * be updated: it's crucial that a pointer to a COPY of the first + * page table entry, obtained through ptep_get(), is provided as @ptentp. + * + * This function will be inlined to optimize based on the input parameters; + * consider using folio_pte_batch() instead if applicable. + * + * Return: the number of table entries in the batch. + */ +static inline unsigned int folio_pte_batch_flags(struct folio *folio, + struct vm_area_struct *vma, pte_t *ptep, pte_t *ptentp, + unsigned int max_nr, fpb_t flags) +{ + bool any_writable = false, any_young = false, any_dirty = false; + pte_t expected_pte, pte = *ptentp; + unsigned int nr, cur_nr; + + VM_WARN_ON_FOLIO(!pte_present(pte), folio); + VM_WARN_ON_FOLIO(!folio_test_large(folio) || max_nr < 1, folio); + VM_WARN_ON_FOLIO(page_folio(pfn_to_page(pte_pfn(pte))) != folio, folio); + /* + * Ensure this is a pointer to a copy not a pointer into a page table. + * If this is a stack value, it won't be a valid virtual address, but + * that's fine because it also cannot be pointing into the page table. + */ + VM_WARN_ON(virt_addr_valid(ptentp) && PageTable(virt_to_page(ptentp))); + + /* Limit max_nr to the actual remaining PFNs in the folio we could batch. */ + max_nr = min_t(unsigned long, max_nr, + folio_pfn(folio) + folio_nr_pages(folio) - pte_pfn(pte)); + + nr = pte_batch_hint(ptep, pte); + expected_pte = __pte_batch_clear_ignored(pte_advance_pfn(pte, nr), flags); + ptep = ptep + nr; + + while (nr < max_nr) { + pte = ptep_get(ptep); + + if (!pte_same(__pte_batch_clear_ignored(pte, flags), expected_pte)) + break; + + if (flags & FPB_MERGE_WRITE) + any_writable |= pte_write(pte); + if (flags & FPB_MERGE_YOUNG_DIRTY) { + any_young |= pte_young(pte); + any_dirty |= pte_dirty(pte); + } + + cur_nr = pte_batch_hint(ptep, pte); + expected_pte = pte_advance_pfn(expected_pte, cur_nr); + ptep += cur_nr; + nr += cur_nr; + } + + if (any_writable) + *ptentp = pte_mkwrite(*ptentp, vma); + if (any_young) + *ptentp = pte_mkyoung(*ptentp); + if (any_dirty) + *ptentp = pte_mkdirty(*ptentp); + + return min(nr, max_nr); +} + +unsigned int folio_pte_batch(struct folio *folio, pte_t *ptep, pte_t pte, + unsigned int max_nr); + +/** + * pte_move_swp_offset - Move the swap entry offset field of a swap pte + * forward or backward by delta + * @pte: The initial pte state; must be a swap entry + * @delta: The direction and the offset we are moving; forward if delta + * is positive; backward if delta is negative + * + * Moves the swap offset, while maintaining all other fields, including + * swap type, and any swp pte bits. The resulting pte is returned. + */ +static inline pte_t pte_move_swp_offset(pte_t pte, long delta) +{ + const softleaf_t entry = softleaf_from_pte(pte); + pte_t new = __swp_entry_to_pte(__swp_entry(swp_type(entry), + (swp_offset(entry) + delta))); + + if (pte_swp_soft_dirty(pte)) + new = pte_swp_mksoft_dirty(new); + if (pte_swp_exclusive(pte)) + new = pte_swp_mkexclusive(new); + if (pte_swp_uffd_wp(pte)) + new = pte_swp_mkuffd_wp(new); + + return new; +} + + +/** + * pte_next_swp_offset - Increment the swap entry offset field of a swap pte. + * @pte: The initial pte state; must be a swap entry. + * + * Increments the swap offset, while maintaining all other fields, including + * swap type, and any swp pte bits. The resulting pte is returned. + */ +static inline pte_t pte_next_swp_offset(pte_t pte) +{ + return pte_move_swp_offset(pte, 1); +} + +/** + * swap_pte_batch - detect a PTE batch for a set of contiguous swap entries + * @start_ptep: Page table pointer for the first entry. + * @max_nr: The maximum number of table entries to consider. + * @pte: Page table entry for the first entry. + * + * Detect a batch of contiguous swap entries: consecutive (non-present) PTEs + * containing swap entries all with consecutive offsets and targeting the same + * swap type, all with matching swp pte bits. + * + * max_nr must be at least one and must be limited by the caller so scanning + * cannot exceed a single page table. + * + * Return: the number of table entries in the batch. + */ +static inline int swap_pte_batch(pte_t *start_ptep, int max_nr, pte_t pte) +{ + pte_t expected_pte = pte_next_swp_offset(pte); + const pte_t *end_ptep = start_ptep + max_nr; + const softleaf_t entry = softleaf_from_pte(pte); + pte_t *ptep = start_ptep + 1; + unsigned short cgroup_id; + + VM_WARN_ON(max_nr < 1); + VM_WARN_ON(!softleaf_is_swap(entry)); + + cgroup_id = lookup_swap_cgroup_id(entry); + while (ptep < end_ptep) { + softleaf_t entry; + + pte = ptep_get(ptep); + + if (!pte_same(pte, expected_pte)) + break; + entry = softleaf_from_pte(pte); + if (lookup_swap_cgroup_id(entry) != cgroup_id) + break; + expected_pte = pte_next_swp_offset(expected_pte); + ptep++; + } + + return ptep - start_ptep; +} +#endif /* CONFIG_MMU */ + +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 __vmf_anon_prepare(struct vm_fault *vmf); +static inline vm_fault_t vmf_anon_prepare(struct vm_fault *vmf) +{ + vm_fault_t ret = __vmf_anon_prepare(vmf); + + if (unlikely(ret & VM_FAULT_RETRY)) + vma_end_read(vmf->vma); + return ret; +} + +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 zap_page_range_single_batched(struct mmu_gather *tlb, + struct vm_area_struct *vma, unsigned long addr, + unsigned long size, struct zap_details *details); +int folio_unmap_invalidate(struct address_space *mapping, struct folio *folio, + gfp_t gfp); + +void page_cache_ra_order(struct readahead_control *, struct file_ra_state *); +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 mapping_evict_folio(struct address_space *mapping, struct folio *folio); +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: */ -extern int isolate_lru_page(struct page *page); -extern void putback_lru_page(struct page *page); +bool folio_isolate_lru(struct folio *folio); +void folio_putback_lru(struct folio *folio); +extern void reclaim_throttle(pg_data_t *pgdat, enum vmscan_throttle_state reason); +#ifdef CONFIG_NUMA +int user_proactive_reclaim(char *buf, + struct mem_cgroup *memcg, pg_data_t *pgdat); +#else +static inline int user_proactive_reclaim(char *buf, + struct mem_cgroup *memcg, pg_data_t *pgdat) +{ + return 0; +} +#endif /* * in mm/rmap.c: */ -extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); +pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); /* * in mm/page_alloc.c */ -extern void __free_pages_bootmem(struct page *page, unsigned int order); -extern void prep_compound_page(struct page *page, unsigned long order); -#ifdef CONFIG_MEMORY_FAILURE -extern bool is_free_buddy_page(struct page *page); +#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; +extern int defrag_mode; + +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_PAGE_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); +bool pfn_range_intersects_zones(int nid, unsigned long start_pfn, + unsigned long nr_pages); + +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, + enum meminit_context context); + +/* + * 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; + VM_WARN_ON_ONCE(order > MAX_FOLIO_ORDER); + + folio->_flags_1 = (folio->_flags_1 & ~0xffUL) | order; +#ifdef NR_PAGES_IN_LARGE_FOLIO + folio->_nr_pages = 1U << order; #endif +} + +bool __folio_unqueue_deferred_split(struct folio *folio); +static inline bool folio_unqueue_deferred_split(struct folio *folio) +{ + if (folio_order(folio) <= 1 || !folio_test_large_rmappable(folio)) + return false; + + /* + * At this point, there is no one trying to add the folio to + * deferred_list. If folio is not in deferred_list, it's safe + * to check without acquiring the split_queue_lock. + */ + if (data_race(list_empty(&folio->_deferred_list))) + return false; + + return __folio_unqueue_deferred_split(folio); +} + +static inline struct folio *page_rmappable_folio(struct page *page) +{ + struct folio *folio = (struct folio *)page; + + if (folio && folio_test_large(folio)) + folio_set_large_rmappable(folio); + return 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->_large_mapcount, -1); + if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT)) + atomic_set(&folio->_nr_pages_mapped, 0); + if (IS_ENABLED(CONFIG_MM_ID)) { + folio->_mm_ids = 0; + folio->_mm_id_mapcount[0] = -1; + folio->_mm_id_mapcount[1] = -1; + } + if (IS_ENABLED(CONFIG_64BIT) || order > 1) { + atomic_set(&folio->_pincount, 0); + atomic_set(&folio->_entire_mapcount, -1); + } + if (order > 1) + INIT_LIST_HEAD(&folio->_deferred_list); +} + +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); +} + +void post_alloc_hook(struct page *page, unsigned int order, gfp_t gfp_flags); +extern bool free_pages_prepare(struct page *page, unsigned int order); + +extern int user_min_free_kbytes; + +struct page *__alloc_frozen_pages_noprof(gfp_t, unsigned int order, int nid, + nodemask_t *); +#define __alloc_frozen_pages(...) \ + alloc_hooks(__alloc_frozen_pages_noprof(__VA_ARGS__)) +void free_frozen_pages(struct page *page, unsigned int order); +void free_unref_folios(struct folio_batch *fbatch); + +#ifdef CONFIG_NUMA +struct page *alloc_frozen_pages_noprof(gfp_t, unsigned int order); +#else +static inline struct page *alloc_frozen_pages_noprof(gfp_t gfp, unsigned int order) +{ + return __alloc_frozen_pages_noprof(gfp, order, numa_node_id(), NULL); +} +#endif + +#define alloc_frozen_pages(...) \ + alloc_hooks(alloc_frozen_pages_noprof(__VA_ARGS__)) + +struct page *alloc_frozen_pages_nolock_noprof(gfp_t gfp_flags, int nid, unsigned int order); +#define alloc_frozen_pages_nolock(...) \ + alloc_hooks(alloc_frozen_pages_nolock_noprof(__VA_ARGS__)) + +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, + bool); #if defined CONFIG_COMPACTION || defined CONFIG_CMA @@ -113,172 +873,291 @@ extern bool is_free_buddy_page(struct page *page); * completes when free_pfn <= migrate_pfn */ struct compact_control { - struct list_head freepages; /* List of free pages to migrate to */ + struct list_head freepages[NR_PAGE_ORDERS]; /* List of free pages to migrate to */ struct list_head migratepages; /* List of pages being migrated */ - unsigned long nr_freepages; /* Number of isolated free pages */ - unsigned long nr_migratepages; /* Number of pages to migrate */ + 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 */ - unsigned long migrate_pfn; /* isolate_migratepages search base */ - bool sync; /* Synchronous migration */ + /* + * 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 finished_update_free; /* True when the zone cached pfns are - * no longer being updated + 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 finished_update_migrate; + bool alloc_contig; /* alloc_contig_range allocation */ +}; - int order; /* order a direct compactor needs */ - int migratetype; /* MOVABLE, RECLAIMABLE etc */ - struct zone *zone; - bool contended; /* True if a lock was contended */ +/* + * 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); -unsigned long -isolate_migratepages_range(struct zone *zone, struct compact_control *cc, - unsigned long low_pfn, unsigned long end_pfn, bool unevictable); +int +isolate_migratepages_range(struct compact_control *cc, + unsigned long low_pfn, unsigned long end_pfn); + +/* Free whole pageblock and set its migration type to MIGRATE_CMA. */ +void init_cma_reserved_pageblock(struct page *page); +#endif /* CONFIG_COMPACTION || CONFIG_CMA */ + +struct cma; + +#ifdef CONFIG_CMA +void *cma_reserve_early(struct cma *cma, unsigned long size); +void init_cma_pageblock(struct page *page); +#else +static inline void *cma_reserve_early(struct cma *cma, unsigned long size) +{ + return NULL; +} +static inline void init_cma_pageblock(struct page *page) +{ +} #endif -/* - * function for dealing with page's order in buddy system. - * zone->lock is already acquired when we use these. - * So, we don't need atomic page->flags operations here. - */ -static inline unsigned long page_order(struct page *page) + +int find_suitable_fallback(struct free_area *area, unsigned int order, + int migratetype, bool claimable); + +static inline bool free_area_empty(struct free_area *area, int migratetype) { - /* PageBuddy() must be checked by the caller */ - return page_private(page); + return list_empty(&area->free_list[migratetype]); } /* mm/util.c */ -void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma, - struct vm_area_struct *prev, struct rb_node *rb_parent); +struct anon_vma *folio_anon_vma(const struct folio *folio); #ifdef CONFIG_MMU -extern long __mlock_vma_pages_range(struct vm_area_struct *vma, - unsigned long start, unsigned long end, int *nonblocking); -extern void munlock_vma_pages_range(struct vm_area_struct *vma, - unsigned long start, unsigned long end); -static inline void munlock_vma_pages_all(struct vm_area_struct *vma) -{ - munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end); -} +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_page_range(struct mm_struct *mm, unsigned long start, + unsigned long end, bool write, int *locked); +bool mlock_future_ok(const struct mm_struct *mm, vm_flags_t vm_flags, + unsigned long bytes); /* - * Called only in fault path, to determine if a new page is being - * mapped into a LOCKED vma. If it is, mark page as mlocked. + * NOTE: This function can't tell whether the folio is "fully mapped" in the + * range. + * "fully mapped" means all the pages of folio is associated with the page + * table of range while this function just check whether the folio range is + * within the range [start, end). Function caller needs to do page table + * check if it cares about the page table association. + * + * Typical usage (like mlock or madvise) is: + * Caller knows at least 1 page of folio is associated with page table of VMA + * and the range [start, end) is intersect with the VMA range. Caller wants + * to know whether the folio is fully associated with the range. It calls + * this function to check whether the folio is in the range first. Then checks + * the page table to know whether the folio is fully mapped to the range. */ -static inline int mlocked_vma_newpage(struct vm_area_struct *vma, - struct page *page) +static inline bool +folio_within_range(struct folio *folio, struct vm_area_struct *vma, + unsigned long start, unsigned long end) { - VM_BUG_ON(PageLRU(page)); + pgoff_t pgoff, addr; + unsigned long vma_pglen = vma_pages(vma); - if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) - return 0; + VM_WARN_ON_FOLIO(folio_test_ksm(folio), folio); + if (start > end) + return false; - if (!TestSetPageMlocked(page)) { - mod_zone_page_state(page_zone(page), NR_MLOCK, - hpage_nr_pages(page)); - count_vm_event(UNEVICTABLE_PGMLOCKED); - } - return 1; + if (start < vma->vm_start) + start = vma->vm_start; + + if (end > vma->vm_end) + end = vma->vm_end; + + pgoff = folio_pgoff(folio); + + /* if folio start address is not in vma range */ + if (!in_range(pgoff, vma->vm_pgoff, vma_pglen)) + return false; + + addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); + + return !(addr < start || end - addr < folio_size(folio)); } -/* - * must be called with vma's mmap_sem held for read or write, and page locked. - */ -extern void mlock_vma_page(struct page *page); -extern unsigned int munlock_vma_page(struct page *page); +static inline bool +folio_within_vma(struct folio *folio, struct vm_area_struct *vma) +{ + return folio_within_range(folio, vma, vma->vm_start, vma->vm_end); +} /* - * Clear the page's PageMlocked(). This can be useful in a situation where - * we want to unconditionally remove a page from the pagecache -- e.g., - * on truncation or freeing. + * 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. * - * It is legal to call this function for any page, mlocked or not. - * If called for a page that is still mapped by mlocked vmas, all we do - * is revert to lazy LRU behaviour -- semantics are not broken. - */ -extern void clear_page_mlock(struct page *page); - -/* - * mlock_migrate_page - called only from migrate_page_copy() to - * migrate the Mlocked page flag; update statistics. + * mlock is usually called at the end of folio_add_*_rmap_*(), munlock at + * the end of folio_remove_rmap_*(); but new anon folios are managed by + * folio_add_lru_vma() calling mlock_new_folio(). */ -static inline void mlock_migrate_page(struct page *newpage, struct page *page) +void mlock_folio(struct folio *folio); +static inline void mlock_vma_folio(struct folio *folio, + struct vm_area_struct *vma) { - if (TestClearPageMlocked(page)) { - unsigned long flags; - int nr_pages = hpage_nr_pages(page); + /* + * 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)) + mlock_folio(folio); +} - local_irq_save(flags); - __mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages); - SetPageMlocked(newpage); - __mod_zone_page_state(page_zone(newpage), NR_MLOCK, nr_pages); - local_irq_restore(flags); - } +void munlock_folio(struct folio *folio); +static inline void munlock_vma_folio(struct folio *folio, + struct vm_area_struct *vma) +{ + /* + * munlock if the function is called. Ideally, we should only + * do munlock if any page of folio is unmapped from VMA and + * cause folio not fully mapped to VMA. + * + * But it's not easy to confirm that's the situation. So we + * always munlock the folio and page reclaim will correct it + * if it's wrong. + */ + if (unlikely(vma->vm_flags & VM_LOCKED)) + 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); -#ifdef CONFIG_TRANSPARENT_HUGEPAGE -extern unsigned long vma_address(struct page *page, - struct vm_area_struct *vma); -#endif -#else /* !CONFIG_MMU */ -static inline int mlocked_vma_newpage(struct vm_area_struct *v, struct page *p) +/** + * vma_address - Find the virtual address a page range is mapped at + * @vma: The vma which maps this object. + * @pgoff: The page offset within its object. + * @nr_pages: The number of pages to consider. + * + * If any page in this range is mapped by this VMA, return the first address + * where any of these pages appear. Otherwise, return -EFAULT. + */ +static inline unsigned long vma_address(const struct vm_area_struct *vma, + pgoff_t pgoff, unsigned long nr_pages) { - return 0; -} -static inline void clear_page_mlock(struct page *page) { } -static inline void mlock_vma_page(struct page *page) { } -static inline void mlock_migrate_page(struct page *new, struct page *old) { } + unsigned long address; -#endif /* !CONFIG_MMU */ + 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 mem_map entry representing the 'offset' subpage within - * the maximally aligned gigantic page 'base'. Handle any discontiguity - * in the mem_map at MAX_ORDER_NR_PAGES boundaries. + * 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 struct page *mem_map_offset(struct page *base, int offset) +static inline unsigned long vma_address_end(struct page_vma_mapped_walk *pvmw) { - if (unlikely(offset >= MAX_ORDER_NR_PAGES)) - return pfn_to_page(page_to_pfn(base) + offset); - return base + offset; + 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; } -/* - * Iterator over all subpages within the maximally aligned gigantic - * page 'base'. Handle any discontiguity in the mem_map. - */ -static inline struct page *mem_map_next(struct page *iter, - struct page *base, int offset) +static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf, + struct file *fpin) { - if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) { - unsigned long pfn = page_to_pfn(base) + offset; - if (!pfn_valid(pfn)) - return NULL; - return pfn_to_page(pfn); + 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 iter + 1; + return fpin; } - -/* - * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node, - * so all functions starting at paging_init should be marked __init - * in those cases. SPARSEMEM, however, allows for memory hotplug, - * and alloc_bootmem_node is not used. - */ -#ifdef CONFIG_SPARSEMEM -#define __paginginit __meminit -#else -#define __paginginit __init -#endif +#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 */ + +void init_deferred_page(unsigned long pfn, int nid); + enum mminit_level { MMINIT_WARNING, MMINIT_VERIFY, @@ -292,16 +1171,15 @@ extern int mminit_loglevel; #define mminit_dprintk(level, prefix, fmt, arg...) \ do { \ if (level < mminit_loglevel) { \ - printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \ - printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \ + 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_page_links(struct page *page, - enum zone_type zone, unsigned long nid, unsigned long pfn); extern void mminit_verify_zonelist(void); - #else static inline void mminit_dprintk(enum mminit_level level, @@ -313,48 +1191,78 @@ static inline void mminit_verify_pageflags_layout(void) { } -static inline void mminit_verify_page_links(struct page *page, - enum zone_type zone, unsigned long nid, unsigned long pfn) -{ -} - static inline void mminit_verify_zonelist(void) { } #endif /* CONFIG_DEBUG_MEMORY_INIT */ -/* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */ -#if defined(CONFIG_SPARSEMEM) -extern void mminit_validate_memmodel_limits(unsigned long *start_pfn, - unsigned long *end_pfn); +#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_mode; + +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 void mminit_validate_memmodel_limits(unsigned long *start_pfn, - unsigned long *end_pfn) +#define node_reclaim_mode 0 + +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 + +static inline bool node_reclaim_enabled(void) { + /* Is any node_reclaim_mode bit set? */ + return node_reclaim_mode & (RECLAIM_ZONE|RECLAIM_WRITE|RECLAIM_UNMAP); } -#endif /* CONFIG_SPARSEMEM */ -#define ZONE_RECLAIM_NOSCAN -2 -#define ZONE_RECLAIM_FULL -1 -#define ZONE_RECLAIM_SOME 0 -#define ZONE_RECLAIM_SUCCESS 1 +/* + * mm/memory-failure.c + */ +#ifdef CONFIG_MEMORY_FAILURE +int unmap_poisoned_folio(struct folio *folio, unsigned long pfn, bool must_kill); +void shake_folio(struct folio *folio); +typedef int hwpoison_filter_func_t(struct page *p); +void hwpoison_filter_register(hwpoison_filter_func_t *filter); +void hwpoison_filter_unregister(void); -extern int hwpoison_filter(struct page *p); +#define MAGIC_HWPOISON 0x48575053U /* HWPS */ +void SetPageHWPoisonTakenOff(struct page *page); +void ClearPageHWPoisonTakenOff(struct page *page); +bool take_page_off_buddy(struct page *page); +bool put_page_back_buddy(struct page *page); +struct task_struct *task_early_kill(struct task_struct *tsk, int force_early); +void add_to_kill_ksm(struct task_struct *tsk, const struct page *p, + struct vm_area_struct *vma, struct list_head *to_kill, + unsigned long ksm_addr); +unsigned long page_mapped_in_vma(const struct page *page, + struct vm_area_struct *vma); -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; +#else +static inline int unmap_poisoned_folio(struct folio *folio, unsigned long pfn, bool must_kill) +{ + return -EBUSY; +} +#endif -extern unsigned long vm_mmap_pgoff(struct file *, unsigned long, +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_clean_pages_from_list(struct zone *zone, - struct list_head *page_list); +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 @@ -364,9 +1272,440 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, /* Mask to get the watermark bits */ #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) -#define ALLOC_HARDER 0x10 /* try to alloc harder */ -#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */ -#define ALLOC_CPUSET 0x40 /* check for correct cpuset */ -#define ALLOC_CMA 0x80 /* allow allocations from CMA areas */ +/* + * 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_TRYLOCK 0x400 /* Only use spin_trylock in allocation path */ +#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 vmaflag_names[]; +extern const struct trace_print_flags gfpflag_names[]; + +void setup_zone_pageset(struct zone *zone); + +struct migration_target_control { + int nid; /* preferred node id */ + nodemask_t *nmask; + gfp_t gfp_mask; + enum migrate_reason reason; +}; + +/* + * 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, gfp_t gfp_mask); +unsigned int get_vm_area_page_order(struct vm_struct *vm); +#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, gfp_t gfp_mask) +{ + 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); + +static inline bool vma_is_single_threaded_private(struct vm_area_struct *vma) +{ + if (vma->vm_flags & VM_SHARED) + return false; + + return atomic_read(&vma->vm_mm->mm_users) == 1; +} + +#ifdef CONFIG_NUMA_BALANCING +bool folio_can_map_prot_numa(struct folio *folio, struct vm_area_struct *vma, + bool is_private_single_threaded); + +#else +static inline bool folio_can_map_prot_numa(struct folio *folio, + struct vm_area_struct *vma, bool is_private_single_threaded) +{ + return false; +} +#endif + +int numa_migrate_check(struct folio *folio, struct vm_fault *vmf, + unsigned long addr, int *flags, bool writable, + int *last_cpupid); + +void free_zone_device_folio(struct folio *folio); +int migrate_device_coherent_folio(struct folio *folio); + +struct vm_struct *__get_vm_area_node(unsigned long size, + unsigned long align, unsigned long shift, + unsigned long vm_flags, unsigned long start, + unsigned long end, int node, gfp_t gfp_mask, + const void *caller); + +/* + * mm/gup.c + */ +int __must_check try_grab_folio(struct folio *folio, int refs, + unsigned int flags); + +/* + * mm/huge_memory.c + */ +void touch_pud(struct vm_area_struct *vma, unsigned long addr, + pud_t *pud, bool write); +bool touch_pmd(struct vm_area_struct *vma, unsigned long addr, + pmd_t *pmd, bool write); + +/* + * Parses a string with mem suffixes into its order. Useful to parse kernel + * parameters. + */ +static inline int get_order_from_str(const char *size_str, + unsigned long valid_orders) +{ + unsigned long size; + char *endptr; + int order; + + size = memparse(size_str, &endptr); + + if (!is_power_of_2(size)) + return -EINVAL; + order = get_order(size); + if (BIT(order) & ~valid_orders) + return -EINVAL; + + return order; +} + +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, + /* VMA lookup+checks compatible with MADV_POPULATE_(READ|WRITE) */ + FOLL_MADV_POPULATE = 1 << 22, +}; + +#define INTERNAL_GUP_FLAGS (FOLL_TOUCH | FOLL_TRIED | FOLL_REMOTE | FOLL_PIN | \ + FOLL_FAST_ONLY | FOLL_UNLOCKABLE | \ + FOLL_MADV_POPULATE) + +/* + * 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 + * folio_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 folio_try_share_anon_rmap_*(). */ + if (IS_ENABLED(CONFIG_HAVE_GUP_FAST)) + smp_rmb(); + + /* + * Note that KSM pages cannot be exclusive, and consequently, + * cannot get pinned. + */ + return !PageAnonExclusive(page); +} + +extern bool mirrored_kernelcore; +bool memblock_has_mirror(void); +void memblock_free_all(void); + +static __always_inline void vma_set_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end, + pgoff_t pgoff) +{ + vma->vm_start = start; + vma->vm_end = end; + vma->vm_pgoff = pgoff; +} + +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 (!pgtable_supports_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 bool pmd_needs_soft_dirty_wp(struct vm_area_struct *vma, pmd_t pmd) +{ + return vma_soft_dirty_enabled(vma) && !pmd_soft_dirty(pmd); +} + +static inline bool pte_needs_soft_dirty_wp(struct vm_area_struct *vma, pte_t pte) +{ + return vma_soft_dirty_enabled(vma) && !pte_soft_dirty(pte); +} + +void __meminit __init_single_page(struct page *page, unsigned long pfn, + unsigned long zone, int nid); +void __meminit __init_page_from_nid(unsigned long pfn, int nid); + +/* shrinker related functions */ +unsigned long shrink_slab(gfp_t gfp_mask, int nid, struct mem_cgroup *memcg, + int priority); + +int shmem_add_to_page_cache(struct folio *folio, + struct address_space *mapping, + pgoff_t index, void *expected, gfp_t gfp); +int shmem_inode_acct_blocks(struct inode *inode, long pages); +bool shmem_recalc_inode(struct inode *inode, long alloced, long swapped); + +#ifdef CONFIG_SHRINKER_DEBUG +static inline __printf(2, 0) int shrinker_debugfs_name_alloc( + struct shrinker *shrinker, const char *fmt, va_list ap) +{ + shrinker->name = kvasprintf_const(GFP_KERNEL, fmt, ap); + + return shrinker->name ? 0 : -ENOMEM; +} + +static inline void shrinker_debugfs_name_free(struct shrinker *shrinker) +{ + kfree_const(shrinker->name); + shrinker->name = NULL; +} + +extern int shrinker_debugfs_add(struct shrinker *shrinker); +extern struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, + int *debugfs_id); +extern void shrinker_debugfs_remove(struct dentry *debugfs_entry, + int debugfs_id); +#else /* CONFIG_SHRINKER_DEBUG */ +static inline int shrinker_debugfs_add(struct shrinker *shrinker) +{ + return 0; +} +static inline int shrinker_debugfs_name_alloc(struct shrinker *shrinker, + const char *fmt, va_list ap) +{ + return 0; +} +static inline void shrinker_debugfs_name_free(struct shrinker *shrinker) +{ +} +static inline struct dentry *shrinker_debugfs_detach(struct shrinker *shrinker, + int *debugfs_id) +{ + *debugfs_id = -1; + return NULL; +} +static inline void shrinker_debugfs_remove(struct dentry *debugfs_entry, + int debugfs_id) +{ +} +#endif /* CONFIG_SHRINKER_DEBUG */ + +/* Only track the nodes of mappings with shadow entries */ +void workingset_update_node(struct xa_node *node); +extern struct list_lru shadow_nodes; +#define mapping_set_update(xas, mapping) do { \ + if (!dax_mapping(mapping) && !shmem_mapping(mapping)) { \ + xas_set_update(xas, workingset_update_node); \ + xas_set_lru(xas, &shadow_nodes); \ + } \ +} while (0) + +/* mremap.c */ +unsigned long move_page_tables(struct pagetable_move_control *pmc); + +#ifdef CONFIG_UNACCEPTED_MEMORY +void accept_page(struct page *page); +#else /* CONFIG_UNACCEPTED_MEMORY */ +static inline void accept_page(struct page *page) +{ +} +#endif /* CONFIG_UNACCEPTED_MEMORY */ + +/* pagewalk.c */ +int walk_page_range_mm_unsafe(struct mm_struct *mm, unsigned long start, + unsigned long end, const struct mm_walk_ops *ops, + void *private); +int walk_page_range_vma_unsafe(struct vm_area_struct *vma, unsigned long start, + unsigned long end, const struct mm_walk_ops *ops, + void *private); +int walk_page_range_debug(struct mm_struct *mm, unsigned long start, + unsigned long end, const struct mm_walk_ops *ops, + pgd_t *pgd, void *private); + +/* pt_reclaim.c */ +bool try_get_and_clear_pmd(struct mm_struct *mm, pmd_t *pmd, pmd_t *pmdval); +void free_pte(struct mm_struct *mm, unsigned long addr, struct mmu_gather *tlb, + pmd_t pmdval); +void try_to_free_pte(struct mm_struct *mm, pmd_t *pmd, unsigned long addr, + struct mmu_gather *tlb); + +#ifdef CONFIG_PT_RECLAIM +bool reclaim_pt_is_enabled(unsigned long start, unsigned long end, + struct zap_details *details); +#else +static inline bool reclaim_pt_is_enabled(unsigned long start, unsigned long end, + struct zap_details *details) +{ + return false; +} +#endif /* CONFIG_PT_RECLAIM */ + +void dup_mm_exe_file(struct mm_struct *mm, struct mm_struct *oldmm); +int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm); + +void remap_pfn_range_prepare(struct vm_area_desc *desc, unsigned long pfn); +int remap_pfn_range_complete(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn, unsigned long size, pgprot_t pgprot); + +static inline void io_remap_pfn_range_prepare(struct vm_area_desc *desc, + unsigned long orig_pfn, unsigned long size) +{ + const unsigned long pfn = io_remap_pfn_range_pfn(orig_pfn, size); + + return remap_pfn_range_prepare(desc, pfn); +} + +static inline int io_remap_pfn_range_complete(struct vm_area_struct *vma, + unsigned long addr, unsigned long orig_pfn, unsigned long size, + pgprot_t orig_prot) +{ + const unsigned long pfn = io_remap_pfn_range_pfn(orig_pfn, size); + const pgprot_t prot = pgprot_decrypted(orig_prot); + + return remap_pfn_range_complete(vma, addr, pfn, size, prot); +} #endif /* __MM_INTERNAL_H */ |