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Diffstat (limited to 'include/linux/mm.h')
| -rw-r--r-- | include/linux/mm.h | 3532 |
1 files changed, 3532 insertions, 0 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h new file mode 100644 index 000000000..eefb09481 --- /dev/null +++ b/include/linux/mm.h @@ -0,0 +1,3532 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_MM_H +#define _LINUX_MM_H + +#include <linux/errno.h> +#include <linux/mmdebug.h> +#include <linux/gfp.h> +#include <linux/bug.h> +#include <linux/list.h> +#include <linux/mmzone.h> +#include <linux/rbtree.h> +#include <linux/atomic.h> +#include <linux/debug_locks.h> +#include <linux/mm_types.h> +#include <linux/mmap_lock.h> +#include <linux/range.h> +#include <linux/pfn.h> +#include <linux/percpu-refcount.h> +#include <linux/bit_spinlock.h> +#include <linux/shrinker.h> +#include <linux/resource.h> +#include <linux/page_ext.h> +#include <linux/err.h> +#include <linux/page-flags.h> +#include <linux/page_ref.h> +#include <linux/overflow.h> +#include <linux/sizes.h> +#include <linux/sched.h> +#include <linux/pgtable.h> +#include <linux/kasan.h> +#include <linux/memremap.h> + +struct mempolicy; +struct anon_vma; +struct anon_vma_chain; +struct user_struct; +struct pt_regs; + +extern int sysctl_page_lock_unfairness; + +void init_mm_internals(void); + +#ifndef CONFIG_NUMA /* Don't use mapnrs, do it properly */ +extern unsigned long max_mapnr; + +static inline void set_max_mapnr(unsigned long limit) +{ + max_mapnr = limit; +} +#else +static inline void set_max_mapnr(unsigned long limit) { } +#endif + +extern atomic_long_t _totalram_pages; +static inline unsigned long totalram_pages(void) +{ + return (unsigned long)atomic_long_read(&_totalram_pages); +} + +static inline void totalram_pages_inc(void) +{ + atomic_long_inc(&_totalram_pages); +} + +static inline void totalram_pages_dec(void) +{ + atomic_long_dec(&_totalram_pages); +} + +static inline void totalram_pages_add(long count) +{ + atomic_long_add(count, &_totalram_pages); +} + +extern void * high_memory; +extern int page_cluster; + +#ifdef CONFIG_SYSCTL +extern int sysctl_legacy_va_layout; +#else +#define sysctl_legacy_va_layout 0 +#endif + +#ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS +extern const int mmap_rnd_bits_min; +extern const int mmap_rnd_bits_max; +extern int mmap_rnd_bits __read_mostly; +#endif +#ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS +extern const int mmap_rnd_compat_bits_min; +extern const int mmap_rnd_compat_bits_max; +extern int mmap_rnd_compat_bits __read_mostly; +#endif + +#include <asm/page.h> +#include <asm/processor.h> + +/* + * Architectures that support memory tagging (assigning tags to memory regions, + * embedding these tags into addresses that point to these memory regions, and + * checking that the memory and the pointer tags match on memory accesses) + * redefine this macro to strip tags from pointers. + * It's defined as noop for architectures that don't support memory tagging. + */ +#ifndef untagged_addr +#define untagged_addr(addr) (addr) +#endif + +#ifndef __pa_symbol +#define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0)) +#endif + +#ifndef page_to_virt +#define page_to_virt(x) __va(PFN_PHYS(page_to_pfn(x))) +#endif + +#ifndef lm_alias +#define lm_alias(x) __va(__pa_symbol(x)) +#endif + +/* + * To prevent common memory management code establishing + * a zero page mapping on a read fault. + * This macro should be defined within <asm/pgtable.h>. + * s390 does this to prevent multiplexing of hardware bits + * related to the physical page in case of virtualization. + */ +#ifndef mm_forbids_zeropage +#define mm_forbids_zeropage(X) (0) +#endif + +/* + * On some architectures it is expensive to call memset() for small sizes. + * If an architecture decides to implement their own version of + * mm_zero_struct_page they should wrap the defines below in a #ifndef and + * define their own version of this macro in <asm/pgtable.h> + */ +#if BITS_PER_LONG == 64 +/* This function must be updated when the size of struct page grows above 96 + * or reduces below 56. The idea that compiler optimizes out switch() + * statement, and only leaves move/store instructions. Also the compiler can + * combine write statements if they are both assignments and can be reordered, + * this can result in several of the writes here being dropped. + */ +#define mm_zero_struct_page(pp) __mm_zero_struct_page(pp) +static inline void __mm_zero_struct_page(struct page *page) +{ + unsigned long *_pp = (void *)page; + + /* Check that struct page is either 56, 64, 72, 80, 88 or 96 bytes */ + BUILD_BUG_ON(sizeof(struct page) & 7); + BUILD_BUG_ON(sizeof(struct page) < 56); + BUILD_BUG_ON(sizeof(struct page) > 96); + + switch (sizeof(struct page)) { + case 96: + _pp[11] = 0; + fallthrough; + case 88: + _pp[10] = 0; + fallthrough; + case 80: + _pp[9] = 0; + fallthrough; + case 72: + _pp[8] = 0; + fallthrough; + case 64: + _pp[7] = 0; + fallthrough; + case 56: + _pp[6] = 0; + _pp[5] = 0; + _pp[4] = 0; + _pp[3] = 0; + _pp[2] = 0; + _pp[1] = 0; + _pp[0] = 0; + } +} +#else +#define mm_zero_struct_page(pp) ((void)memset((pp), 0, sizeof(struct page))) +#endif + +/* + * Default maximum number of active map areas, this limits the number of vmas + * per mm struct. Users can overwrite this number by sysctl but there is a + * problem. + * + * When a program's coredump is generated as ELF format, a section is created + * per a vma. In ELF, the number of sections is represented in unsigned short. + * This means the number of sections should be smaller than 65535 at coredump. + * Because the kernel adds some informative sections to a image of program at + * generating coredump, we need some margin. The number of extra sections is + * 1-3 now and depends on arch. We use "5" as safe margin, here. + * + * ELF extended numbering allows more than 65535 sections, so 16-bit bound is + * not a hard limit any more. Although some userspace tools can be surprised by + * that. + */ +#define MAPCOUNT_ELF_CORE_MARGIN (5) +#define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN) + +extern int sysctl_max_map_count; + +extern unsigned long sysctl_user_reserve_kbytes; +extern unsigned long sysctl_admin_reserve_kbytes; + +extern int sysctl_overcommit_memory; +extern int sysctl_overcommit_ratio; +extern unsigned long sysctl_overcommit_kbytes; + +int overcommit_ratio_handler(struct ctl_table *, int, void *, size_t *, + loff_t *); +int overcommit_kbytes_handler(struct ctl_table *, int, void *, size_t *, + loff_t *); +int overcommit_policy_handler(struct ctl_table *, int, void *, size_t *, + loff_t *); + +#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) +#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n)) +#define folio_page_idx(folio, p) (page_to_pfn(p) - folio_pfn(folio)) +#else +#define nth_page(page,n) ((page) + (n)) +#define folio_page_idx(folio, p) ((p) - &(folio)->page) +#endif + +/* to align the pointer to the (next) page boundary */ +#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE) + +/* to align the pointer to the (prev) page boundary */ +#define PAGE_ALIGN_DOWN(addr) ALIGN_DOWN(addr, PAGE_SIZE) + +/* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */ +#define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)(addr), PAGE_SIZE) + +#define lru_to_page(head) (list_entry((head)->prev, struct page, lru)) +static inline struct folio *lru_to_folio(struct list_head *head) +{ + return list_entry((head)->prev, struct folio, lru); +} + +void setup_initial_init_mm(void *start_code, void *end_code, + void *end_data, void *brk); + +/* + * Linux kernel virtual memory manager primitives. + * The idea being to have a "virtual" mm in the same way + * we have a virtual fs - giving a cleaner interface to the + * mm details, and allowing different kinds of memory mappings + * (from shared memory to executable loading to arbitrary + * mmap() functions). + */ + +struct vm_area_struct *vm_area_alloc(struct mm_struct *); +struct vm_area_struct *vm_area_dup(struct vm_area_struct *); +void vm_area_free(struct vm_area_struct *); + +#ifndef CONFIG_MMU +extern struct rb_root nommu_region_tree; +extern struct rw_semaphore nommu_region_sem; + +extern unsigned int kobjsize(const void *objp); +#endif + +/* + * vm_flags in vm_area_struct, see mm_types.h. + * When changing, update also include/trace/events/mmflags.h + */ +#define VM_NONE 0x00000000 + +#define VM_READ 0x00000001 /* currently active flags */ +#define VM_WRITE 0x00000002 +#define VM_EXEC 0x00000004 +#define VM_SHARED 0x00000008 + +/* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */ +#define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */ +#define VM_MAYWRITE 0x00000020 +#define VM_MAYEXEC 0x00000040 +#define VM_MAYSHARE 0x00000080 + +#define VM_GROWSDOWN 0x00000100 /* general info on the segment */ +#define VM_UFFD_MISSING 0x00000200 /* missing pages tracking */ +#define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */ +#define VM_UFFD_WP 0x00001000 /* wrprotect pages tracking */ + +#define VM_LOCKED 0x00002000 +#define VM_IO 0x00004000 /* Memory mapped I/O or similar */ + + /* Used by sys_madvise() */ +#define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ +#define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */ + +#define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ +#define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ +#define VM_LOCKONFAULT 0x00080000 /* Lock the pages covered when they are faulted in */ +#define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ +#define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */ +#define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ +#define VM_SYNC 0x00800000 /* Synchronous page faults */ +#define VM_ARCH_1 0x01000000 /* Architecture-specific flag */ +#define VM_WIPEONFORK 0x02000000 /* Wipe VMA contents in child. */ +#define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */ + +#ifdef CONFIG_MEM_SOFT_DIRTY +# define VM_SOFTDIRTY 0x08000000 /* Not soft dirty clean area */ +#else +# define VM_SOFTDIRTY 0 +#endif + +#define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */ +#define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */ +#define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */ +#define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */ + +#ifdef CONFIG_ARCH_USES_HIGH_VMA_FLAGS +#define VM_HIGH_ARCH_BIT_0 32 /* bit only usable on 64-bit architectures */ +#define VM_HIGH_ARCH_BIT_1 33 /* bit only usable on 64-bit architectures */ +#define VM_HIGH_ARCH_BIT_2 34 /* bit only usable on 64-bit architectures */ +#define VM_HIGH_ARCH_BIT_3 35 /* bit only usable on 64-bit architectures */ +#define VM_HIGH_ARCH_BIT_4 36 /* bit only usable on 64-bit architectures */ +#define VM_HIGH_ARCH_0 BIT(VM_HIGH_ARCH_BIT_0) +#define VM_HIGH_ARCH_1 BIT(VM_HIGH_ARCH_BIT_1) +#define VM_HIGH_ARCH_2 BIT(VM_HIGH_ARCH_BIT_2) +#define VM_HIGH_ARCH_3 BIT(VM_HIGH_ARCH_BIT_3) +#define VM_HIGH_ARCH_4 BIT(VM_HIGH_ARCH_BIT_4) +#endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */ + +#ifdef CONFIG_ARCH_HAS_PKEYS +# define VM_PKEY_SHIFT VM_HIGH_ARCH_BIT_0 +# define VM_PKEY_BIT0 VM_HIGH_ARCH_0 /* A protection key is a 4-bit value */ +# define VM_PKEY_BIT1 VM_HIGH_ARCH_1 /* on x86 and 5-bit value on ppc64 */ +# define VM_PKEY_BIT2 VM_HIGH_ARCH_2 +# define VM_PKEY_BIT3 VM_HIGH_ARCH_3 +#ifdef CONFIG_PPC +# define VM_PKEY_BIT4 VM_HIGH_ARCH_4 +#else +# define VM_PKEY_BIT4 0 +#endif +#endif /* CONFIG_ARCH_HAS_PKEYS */ + +#if defined(CONFIG_X86) +# define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */ +#elif defined(CONFIG_PPC) +# define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */ +#elif defined(CONFIG_PARISC) +# define VM_GROWSUP VM_ARCH_1 +#elif defined(CONFIG_IA64) +# define VM_GROWSUP VM_ARCH_1 +#elif defined(CONFIG_SPARC64) +# define VM_SPARC_ADI VM_ARCH_1 /* Uses ADI tag for access control */ +# define VM_ARCH_CLEAR VM_SPARC_ADI +#elif defined(CONFIG_ARM64) +# define VM_ARM64_BTI VM_ARCH_1 /* BTI guarded page, a.k.a. GP bit */ +# define VM_ARCH_CLEAR VM_ARM64_BTI +#elif !defined(CONFIG_MMU) +# define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */ +#endif + +#if defined(CONFIG_ARM64_MTE) +# define VM_MTE VM_HIGH_ARCH_0 /* Use Tagged memory for access control */ +# define VM_MTE_ALLOWED VM_HIGH_ARCH_1 /* Tagged memory permitted */ +#else +# define VM_MTE VM_NONE +# define VM_MTE_ALLOWED VM_NONE +#endif + +#ifndef VM_GROWSUP +# define VM_GROWSUP VM_NONE +#endif + +#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR +# define VM_UFFD_MINOR_BIT 37 +# define VM_UFFD_MINOR BIT(VM_UFFD_MINOR_BIT) /* UFFD minor faults */ +#else /* !CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ +# define VM_UFFD_MINOR VM_NONE +#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ + +/* Bits set in the VMA until the stack is in its final location */ +#define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ | VM_STACK_EARLY) + +#define TASK_EXEC ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) + +/* Common data flag combinations */ +#define VM_DATA_FLAGS_TSK_EXEC (VM_READ | VM_WRITE | TASK_EXEC | \ + VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) +#define VM_DATA_FLAGS_NON_EXEC (VM_READ | VM_WRITE | VM_MAYREAD | \ + VM_MAYWRITE | VM_MAYEXEC) +#define VM_DATA_FLAGS_EXEC (VM_READ | VM_WRITE | VM_EXEC | \ + VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) + +#ifndef VM_DATA_DEFAULT_FLAGS /* arch can override this */ +#define VM_DATA_DEFAULT_FLAGS VM_DATA_FLAGS_EXEC +#endif + +#ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */ +#define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS +#endif + +#ifdef CONFIG_STACK_GROWSUP +#define VM_STACK VM_GROWSUP +#define VM_STACK_EARLY VM_GROWSDOWN +#else +#define VM_STACK VM_GROWSDOWN +#define VM_STACK_EARLY 0 +#endif + +#define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) + +/* VMA basic access permission flags */ +#define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC) + + +/* + * Special vmas that are non-mergable, non-mlock()able. + */ +#define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP) + +/* This mask prevents VMA from being scanned with khugepaged */ +#define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB) + +/* This mask defines which mm->def_flags a process can inherit its parent */ +#define VM_INIT_DEF_MASK VM_NOHUGEPAGE + +/* This mask is used to clear all the VMA flags used by mlock */ +#define VM_LOCKED_CLEAR_MASK (~(VM_LOCKED | VM_LOCKONFAULT)) + +/* Arch-specific flags to clear when updating VM flags on protection change */ +#ifndef VM_ARCH_CLEAR +# define VM_ARCH_CLEAR VM_NONE +#endif +#define VM_FLAGS_CLEAR (ARCH_VM_PKEY_FLAGS | VM_ARCH_CLEAR) + +/* + * mapping from the currently active vm_flags protection bits (the + * low four bits) to a page protection mask.. + */ + +/* + * The default fault flags that should be used by most of the + * arch-specific page fault handlers. + */ +#define FAULT_FLAG_DEFAULT (FAULT_FLAG_ALLOW_RETRY | \ + FAULT_FLAG_KILLABLE | \ + FAULT_FLAG_INTERRUPTIBLE) + +/** + * fault_flag_allow_retry_first - check ALLOW_RETRY the first time + * @flags: Fault flags. + * + * This is mostly used for places where we want to try to avoid taking + * the mmap_lock for too long a time when waiting for another condition + * to change, in which case we can try to be polite to release the + * mmap_lock in the first round to avoid potential starvation of other + * processes that would also want the mmap_lock. + * + * Return: true if the page fault allows retry and this is the first + * attempt of the fault handling; false otherwise. + */ +static inline bool fault_flag_allow_retry_first(enum fault_flag flags) +{ + return (flags & FAULT_FLAG_ALLOW_RETRY) && + (!(flags & FAULT_FLAG_TRIED)); +} + +#define FAULT_FLAG_TRACE \ + { FAULT_FLAG_WRITE, "WRITE" }, \ + { FAULT_FLAG_MKWRITE, "MKWRITE" }, \ + { FAULT_FLAG_ALLOW_RETRY, "ALLOW_RETRY" }, \ + { FAULT_FLAG_RETRY_NOWAIT, "RETRY_NOWAIT" }, \ + { FAULT_FLAG_KILLABLE, "KILLABLE" }, \ + { FAULT_FLAG_TRIED, "TRIED" }, \ + { FAULT_FLAG_USER, "USER" }, \ + { FAULT_FLAG_REMOTE, "REMOTE" }, \ + { FAULT_FLAG_INSTRUCTION, "INSTRUCTION" }, \ + { FAULT_FLAG_INTERRUPTIBLE, "INTERRUPTIBLE" } + +/* + * vm_fault is filled by the pagefault handler and passed to the vma's + * ->fault function. The vma's ->fault is responsible for returning a bitmask + * of VM_FAULT_xxx flags that give details about how the fault was handled. + * + * MM layer fills up gfp_mask for page allocations but fault handler might + * alter it if its implementation requires a different allocation context. + * + * pgoff should be used in favour of virtual_address, if possible. + */ +struct vm_fault { + const struct { + struct vm_area_struct *vma; /* Target VMA */ + gfp_t gfp_mask; /* gfp mask to be used for allocations */ + pgoff_t pgoff; /* Logical page offset based on vma */ + unsigned long address; /* Faulting virtual address - masked */ + unsigned long real_address; /* Faulting virtual address - unmasked */ + }; + enum fault_flag flags; /* FAULT_FLAG_xxx flags + * XXX: should really be 'const' */ + pmd_t *pmd; /* Pointer to pmd entry matching + * the 'address' */ + pud_t *pud; /* Pointer to pud entry matching + * the 'address' + */ + union { + pte_t orig_pte; /* Value of PTE at the time of fault */ + pmd_t orig_pmd; /* Value of PMD at the time of fault, + * used by PMD fault only. + */ + }; + + struct page *cow_page; /* Page handler may use for COW fault */ + struct page *page; /* ->fault handlers should return a + * page here, unless VM_FAULT_NOPAGE + * is set (which is also implied by + * VM_FAULT_ERROR). + */ + /* These three entries are valid only while holding ptl lock */ + pte_t *pte; /* Pointer to pte entry matching + * the 'address'. NULL if the page + * table hasn't been allocated. + */ + spinlock_t *ptl; /* Page table lock. + * Protects pte page table if 'pte' + * is not NULL, otherwise pmd. + */ + pgtable_t prealloc_pte; /* Pre-allocated pte page table. + * vm_ops->map_pages() sets up a page + * table from atomic context. + * do_fault_around() pre-allocates + * page table to avoid allocation from + * atomic context. + */ +}; + +/* page entry size for vm->huge_fault() */ +enum page_entry_size { + PE_SIZE_PTE = 0, + PE_SIZE_PMD, + PE_SIZE_PUD, +}; + +/* + * These are the virtual MM functions - opening of an area, closing and + * unmapping it (needed to keep files on disk up-to-date etc), pointer + * to the functions called when a no-page or a wp-page exception occurs. + */ +struct vm_operations_struct { + void (*open)(struct vm_area_struct * area); + /** + * @close: Called when the VMA is being removed from the MM. + * Context: User context. May sleep. Caller holds mmap_lock. + */ + void (*close)(struct vm_area_struct * area); + /* Called any time before splitting to check if it's allowed */ + int (*may_split)(struct vm_area_struct *area, unsigned long addr); + int (*mremap)(struct vm_area_struct *area); + /* + * Called by mprotect() to make driver-specific permission + * checks before mprotect() is finalised. The VMA must not + * be modified. Returns 0 if eprotect() can proceed. + */ + int (*mprotect)(struct vm_area_struct *vma, unsigned long start, + unsigned long end, unsigned long newflags); + vm_fault_t (*fault)(struct vm_fault *vmf); + vm_fault_t (*huge_fault)(struct vm_fault *vmf, + enum page_entry_size pe_size); + vm_fault_t (*map_pages)(struct vm_fault *vmf, + pgoff_t start_pgoff, pgoff_t end_pgoff); + unsigned long (*pagesize)(struct vm_area_struct * area); + + /* notification that a previously read-only page is about to become + * writable, if an error is returned it will cause a SIGBUS */ + vm_fault_t (*page_mkwrite)(struct vm_fault *vmf); + + /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */ + vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf); + + /* called by access_process_vm when get_user_pages() fails, typically + * for use by special VMAs. See also generic_access_phys() for a generic + * implementation useful for any iomem mapping. + */ + int (*access)(struct vm_area_struct *vma, unsigned long addr, + void *buf, int len, int write); + + /* Called by the /proc/PID/maps code to ask the vma whether it + * has a special name. Returning non-NULL will also cause this + * vma to be dumped unconditionally. */ + const char *(*name)(struct vm_area_struct *vma); + +#ifdef CONFIG_NUMA + /* + * set_policy() op must add a reference to any non-NULL @new mempolicy + * to hold the policy upon return. Caller should pass NULL @new to + * remove a policy and fall back to surrounding context--i.e. do not + * install a MPOL_DEFAULT policy, nor the task or system default + * mempolicy. + */ + int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); + + /* + * get_policy() op must add reference [mpol_get()] to any policy at + * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure + * in mm/mempolicy.c will do this automatically. + * get_policy() must NOT add a ref if the policy at (vma,addr) is not + * marked as MPOL_SHARED. vma policies are protected by the mmap_lock. + * If no [shared/vma] mempolicy exists at the addr, get_policy() op + * must return NULL--i.e., do not "fallback" to task or system default + * policy. + */ + struct mempolicy *(*get_policy)(struct vm_area_struct *vma, + unsigned long addr); +#endif + /* + * Called by vm_normal_page() for special PTEs to find the + * page for @addr. This is useful if the default behavior + * (using pte_page()) would not find the correct page. + */ + struct page *(*find_special_page)(struct vm_area_struct *vma, + unsigned long addr); +}; + +static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) +{ + static const struct vm_operations_struct dummy_vm_ops = {}; + + memset(vma, 0, sizeof(*vma)); + vma->vm_mm = mm; + vma->vm_ops = &dummy_vm_ops; + INIT_LIST_HEAD(&vma->anon_vma_chain); +} + +static inline void vma_set_anonymous(struct vm_area_struct *vma) +{ + vma->vm_ops = NULL; +} + +static inline bool vma_is_anonymous(struct vm_area_struct *vma) +{ + return !vma->vm_ops; +} + +static inline bool vma_is_temporary_stack(struct vm_area_struct *vma) +{ + int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP); + + if (!maybe_stack) + return false; + + if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) == + VM_STACK_INCOMPLETE_SETUP) + return true; + + return false; +} + +static inline bool vma_is_foreign(struct vm_area_struct *vma) +{ + if (!current->mm) + return true; + + if (current->mm != vma->vm_mm) + return true; + + return false; +} + +static inline bool vma_is_accessible(struct vm_area_struct *vma) +{ + return vma->vm_flags & VM_ACCESS_FLAGS; +} + +static inline +struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max) +{ + return mas_find(&vmi->mas, max); +} + +static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi) +{ + /* + * Uses vma_find() to get the first VMA when the iterator starts. + * Calling mas_next() could skip the first entry. + */ + return vma_find(vmi, ULONG_MAX); +} + +static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi) +{ + return mas_prev(&vmi->mas, 0); +} + +static inline unsigned long vma_iter_addr(struct vma_iterator *vmi) +{ + return vmi->mas.index; +} + +#define for_each_vma(__vmi, __vma) \ + while (((__vma) = vma_next(&(__vmi))) != NULL) + +/* The MM code likes to work with exclusive end addresses */ +#define for_each_vma_range(__vmi, __vma, __end) \ + while (((__vma) = vma_find(&(__vmi), (__end) - 1)) != NULL) + +#ifdef CONFIG_SHMEM +/* + * The vma_is_shmem is not inline because it is used only by slow + * paths in userfault. + */ +bool vma_is_shmem(struct vm_area_struct *vma); +#else +static inline bool vma_is_shmem(struct vm_area_struct *vma) { return false; } +#endif + +int vma_is_stack_for_current(struct vm_area_struct *vma); + +/* flush_tlb_range() takes a vma, not a mm, and can care about flags */ +#define TLB_FLUSH_VMA(mm,flags) { .vm_mm = (mm), .vm_flags = (flags) } + +struct mmu_gather; +struct inode; + +static inline unsigned int compound_order(struct page *page) +{ + if (!PageHead(page)) + return 0; + return page[1].compound_order; +} + +/** + * folio_order - The allocation order of a folio. + * @folio: The folio. + * + * A folio is composed of 2^order pages. See get_order() for the definition + * of order. + * + * Return: The order of the folio. + */ +static inline unsigned int folio_order(struct folio *folio) +{ + if (!folio_test_large(folio)) + return 0; + return folio->_folio_order; +} + +#include <linux/huge_mm.h> + +/* + * Methods to modify the page usage count. + * + * What counts for a page usage: + * - cache mapping (page->mapping) + * - private data (page->private) + * - page mapped in a task's page tables, each mapping + * is counted separately + * + * Also, many kernel routines increase the page count before a critical + * routine so they can be sure the page doesn't go away from under them. + */ + +/* + * Drop a ref, return true if the refcount fell to zero (the page has no users) + */ +static inline int put_page_testzero(struct page *page) +{ + VM_BUG_ON_PAGE(page_ref_count(page) == 0, page); + return page_ref_dec_and_test(page); +} + +static inline int folio_put_testzero(struct folio *folio) +{ + return put_page_testzero(&folio->page); +} + +/* + * Try to grab a ref unless the page has a refcount of zero, return false if + * that is the case. + * This can be called when MMU is off so it must not access + * any of the virtual mappings. + */ +static inline bool get_page_unless_zero(struct page *page) +{ + return page_ref_add_unless(page, 1, 0); +} + +extern int page_is_ram(unsigned long pfn); + +enum { + REGION_INTERSECTS, + REGION_DISJOINT, + REGION_MIXED, +}; + +int region_intersects(resource_size_t offset, size_t size, unsigned long flags, + unsigned long desc); + +/* Support for virtually mapped pages */ +struct page *vmalloc_to_page(const void *addr); +unsigned long vmalloc_to_pfn(const void *addr); + +/* + * Determine if an address is within the vmalloc range + * + * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there + * is no special casing required. + */ + +#ifndef is_ioremap_addr +#define is_ioremap_addr(x) is_vmalloc_addr(x) +#endif + +#ifdef CONFIG_MMU +extern bool is_vmalloc_addr(const void *x); +extern int is_vmalloc_or_module_addr(const void *x); +#else +static inline bool is_vmalloc_addr(const void *x) +{ + return false; +} +static inline int is_vmalloc_or_module_addr(const void *x) +{ + return 0; +} +#endif + +/* + * How many times the entire folio is mapped as a single unit (eg by a + * PMD or PUD entry). This is probably not what you want, except for + * debugging purposes; look at folio_mapcount() or page_mapcount() + * instead. + */ +static inline int folio_entire_mapcount(struct folio *folio) +{ + VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); + return atomic_read(folio_mapcount_ptr(folio)) + 1; +} + +/* + * Mapcount of compound page as a whole, does not include mapped sub-pages. + * + * Must be called only for compound pages. + */ +static inline int compound_mapcount(struct page *page) +{ + return folio_entire_mapcount(page_folio(page)); +} + +/* + * The atomic page->_mapcount, starts from -1: so that transitions + * both from it and to it can be tracked, using atomic_inc_and_test + * and atomic_add_negative(-1). + */ +static inline void page_mapcount_reset(struct page *page) +{ + atomic_set(&(page)->_mapcount, -1); +} + +int __page_mapcount(struct page *page); + +/* + * Mapcount of 0-order page; when compound sub-page, includes + * compound_mapcount(). + * + * Result is undefined for pages which cannot be mapped into userspace. + * For example SLAB or special types of pages. See function page_has_type(). + * They use this place in struct page differently. + */ +static inline int page_mapcount(struct page *page) +{ + if (unlikely(PageCompound(page))) + return __page_mapcount(page); + return atomic_read(&page->_mapcount) + 1; +} + +int folio_mapcount(struct folio *folio); + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static inline int total_mapcount(struct page *page) +{ + return folio_mapcount(page_folio(page)); +} + +#else +static inline int total_mapcount(struct page *page) +{ + return page_mapcount(page); +} +#endif + +static inline struct page *virt_to_head_page(const void *x) +{ + struct page *page = virt_to_page(x); + + return compound_head(page); +} + +static inline struct folio *virt_to_folio(const void *x) +{ + struct page *page = virt_to_page(x); + + return page_folio(page); +} + +void __folio_put(struct folio *folio); + +void put_pages_list(struct list_head *pages); + +void split_page(struct page *page, unsigned int order); +void folio_copy(struct folio *dst, struct folio *src); + +unsigned long nr_free_buffer_pages(void); + +/* + * Compound pages have a destructor function. Provide a + * prototype for that function and accessor functions. + * These are _only_ valid on the head of a compound page. + */ +typedef void compound_page_dtor(struct page *); + +/* Keep the enum in sync with compound_page_dtors array in mm/page_alloc.c */ +enum compound_dtor_id { + NULL_COMPOUND_DTOR, + COMPOUND_PAGE_DTOR, +#ifdef CONFIG_HUGETLB_PAGE + HUGETLB_PAGE_DTOR, +#endif +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + TRANSHUGE_PAGE_DTOR, +#endif + NR_COMPOUND_DTORS, +}; +extern compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS]; + +static inline void set_compound_page_dtor(struct page *page, + enum compound_dtor_id compound_dtor) +{ + VM_BUG_ON_PAGE(compound_dtor >= NR_COMPOUND_DTORS, page); + page[1].compound_dtor = compound_dtor; +} + +void destroy_large_folio(struct folio *folio); + +static inline int head_compound_pincount(struct page *head) +{ + return atomic_read(compound_pincount_ptr(head)); +} + +static inline void set_compound_order(struct page *page, unsigned int order) +{ + page[1].compound_order = order; +#ifdef CONFIG_64BIT + page[1].compound_nr = 1U << order; +#endif +} + +/* Returns the number of pages in this potentially compound page. */ +static inline unsigned long compound_nr(struct page *page) +{ + if (!PageHead(page)) + return 1; +#ifdef CONFIG_64BIT + return page[1].compound_nr; +#else + return 1UL << compound_order(page); +#endif +} + +/* Returns the number of bytes in this potentially compound page. */ +static inline unsigned long page_size(struct page *page) +{ + return PAGE_SIZE << compound_order(page); +} + +/* Returns the number of bits needed for the number of bytes in a page */ +static inline unsigned int page_shift(struct page *page) +{ + return PAGE_SHIFT + compound_order(page); +} + +/** + * thp_order - Order of a transparent huge page. + * @page: Head page of a transparent huge page. + */ +static inline unsigned int thp_order(struct page *page) +{ + VM_BUG_ON_PGFLAGS(PageTail(page), page); + return compound_order(page); +} + +/** + * thp_nr_pages - The number of regular pages in this huge page. + * @page: The head page of a huge page. + */ +static inline int thp_nr_pages(struct page *page) +{ + VM_BUG_ON_PGFLAGS(PageTail(page), page); + return compound_nr(page); +} + +/** + * thp_size - Size of a transparent huge page. + * @page: Head page of a transparent huge page. + * + * Return: Number of bytes in this page. + */ +static inline unsigned long thp_size(struct page *page) +{ + return PAGE_SIZE << thp_order(page); +} + +void free_compound_page(struct page *page); + +#ifdef CONFIG_MMU +/* + * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when + * servicing faults for write access. In the normal case, do always want + * pte_mkwrite. But get_user_pages can cause write faults for mappings + * that do not have writing enabled, when used by access_process_vm. + */ +static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma) +{ + if (likely(vma->vm_flags & VM_WRITE)) + pte = pte_mkwrite(pte); + return pte; +} + +vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page); +void do_set_pte(struct vm_fault *vmf, struct page *page, unsigned long addr); + +vm_fault_t finish_fault(struct vm_fault *vmf); +vm_fault_t finish_mkwrite_fault(struct vm_fault *vmf); +#endif + +/* + * Multiple processes may "see" the same page. E.g. for untouched + * mappings of /dev/null, all processes see the same page full of + * zeroes, and text pages of executables and shared libraries have + * only one copy in memory, at most, normally. + * + * For the non-reserved pages, page_count(page) denotes a reference count. + * page_count() == 0 means the page is free. page->lru is then used for + * freelist management in the buddy allocator. + * page_count() > 0 means the page has been allocated. + * + * Pages are allocated by the slab allocator in order to provide memory + * to kmalloc and kmem_cache_alloc. In this case, the management of the + * page, and the fields in 'struct page' are the responsibility of mm/slab.c + * unless a particular usage is carefully commented. (the responsibility of + * freeing the kmalloc memory is the caller's, of course). + * + * A page may be used by anyone else who does a __get_free_page(). + * In this case, page_count still tracks the references, and should only + * be used through the normal accessor functions. The top bits of page->flags + * and page->virtual store page management information, but all other fields + * are unused and could be used privately, carefully. The management of this + * page is the responsibility of the one who allocated it, and those who have + * subsequently been given references to it. + * + * The other pages (we may call them "pagecache pages") are completely + * managed by the Linux memory manager: I/O, buffers, swapping etc. + * The following discussion applies only to them. + * + * A pagecache page contains an opaque `private' member, which belongs to the + * page's address_space. Usually, this is the address of a circular list of + * the page's disk buffers. PG_private must be set to tell the VM to call + * into the filesystem to release these pages. + * + * A page may belong to an inode's memory mapping. In this case, page->mapping + * is the pointer to the inode, and page->index is the file offset of the page, + * in units of PAGE_SIZE. + * + * If pagecache pages are not associated with an inode, they are said to be + * anonymous pages. These may become associated with the swapcache, and in that + * case PG_swapcache is set, and page->private is an offset into the swapcache. + * + * In either case (swapcache or inode backed), the pagecache itself holds one + * reference to the page. Setting PG_private should also increment the + * refcount. The each user mapping also has a reference to the page. + * + * The pagecache pages are stored in a per-mapping radix tree, which is + * rooted at mapping->i_pages, and indexed by offset. + * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space + * lists, we instead now tag pages as dirty/writeback in the radix tree. + * + * All pagecache pages may be subject to I/O: + * - inode pages may need to be read from disk, + * - inode pages which have been modified and are MAP_SHARED may need + * to be written back to the inode on disk, + * - anonymous pages (including MAP_PRIVATE file mappings) which have been + * modified may need to be swapped out to swap space and (later) to be read + * back into memory. + */ + +#if defined(CONFIG_ZONE_DEVICE) && defined(CONFIG_FS_DAX) +DECLARE_STATIC_KEY_FALSE(devmap_managed_key); + +bool __put_devmap_managed_page_refs(struct page *page, int refs); +static inline bool put_devmap_managed_page_refs(struct page *page, int refs) +{ + if (!static_branch_unlikely(&devmap_managed_key)) + return false; + if (!is_zone_device_page(page)) + return false; + return __put_devmap_managed_page_refs(page, refs); +} +#else /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */ +static inline bool put_devmap_managed_page_refs(struct page *page, int refs) +{ + return false; +} +#endif /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */ + +static inline bool put_devmap_managed_page(struct page *page) +{ + return put_devmap_managed_page_refs(page, 1); +} + +/* 127: arbitrary random number, small enough to assemble well */ +#define folio_ref_zero_or_close_to_overflow(folio) \ + ((unsigned int) folio_ref_count(folio) + 127u <= 127u) + +/** + * folio_get - Increment the reference count on a folio. + * @folio: The folio. + * + * Context: May be called in any context, as long as you know that + * you have a refcount on the folio. If you do not already have one, + * folio_try_get() may be the right interface for you to use. + */ +static inline void folio_get(struct folio *folio) +{ + VM_BUG_ON_FOLIO(folio_ref_zero_or_close_to_overflow(folio), folio); + folio_ref_inc(folio); +} + +static inline void get_page(struct page *page) +{ + folio_get(page_folio(page)); +} + +bool __must_check try_grab_page(struct page *page, unsigned int flags); + +static inline __must_check bool try_get_page(struct page *page) +{ + page = compound_head(page); + if (WARN_ON_ONCE(page_ref_count(page) <= 0)) + return false; + page_ref_inc(page); + return true; +} + +/** + * folio_put - Decrement the reference count on a folio. + * @folio: The folio. + * + * If the folio's reference count reaches zero, the memory will be + * released back to the page allocator and may be used by another + * allocation immediately. Do not access the memory or the struct folio + * after calling folio_put() unless you can be sure that it wasn't the + * last reference. + * + * Context: May be called in process or interrupt context, but not in NMI + * context. May be called while holding a spinlock. + */ +static inline void folio_put(struct folio *folio) +{ + if (folio_put_testzero(folio)) + __folio_put(folio); +} + +/** + * folio_put_refs - Reduce the reference count on a folio. + * @folio: The folio. + * @refs: The amount to subtract from the folio's reference count. + * + * If the folio's reference count reaches zero, the memory will be + * released back to the page allocator and may be used by another + * allocation immediately. Do not access the memory or the struct folio + * after calling folio_put_refs() unless you can be sure that these weren't + * the last references. + * + * Context: May be called in process or interrupt context, but not in NMI + * context. May be called while holding a spinlock. + */ +static inline void folio_put_refs(struct folio *folio, int refs) +{ + if (folio_ref_sub_and_test(folio, refs)) + __folio_put(folio); +} + +void release_pages(struct page **pages, int nr); + +/** + * folios_put - Decrement the reference count on an array of folios. + * @folios: The folios. + * @nr: How many folios there are. + * + * Like folio_put(), but for an array of folios. This is more efficient + * than writing the loop yourself as it will optimise the locks which + * need to be taken if the folios are freed. + * + * Context: May be called in process or interrupt context, but not in NMI + * context. May be called while holding a spinlock. + */ +static inline void folios_put(struct folio **folios, unsigned int nr) +{ + release_pages((struct page **)folios, nr); +} + +static inline void put_page(struct page *page) +{ + struct folio *folio = page_folio(page); + + /* + * For some devmap managed pages we need to catch refcount transition + * from 2 to 1: + */ + if (put_devmap_managed_page(&folio->page)) + return; + folio_put(folio); +} + +/* + * GUP_PIN_COUNTING_BIAS, and the associated functions that use it, overload + * the page's refcount so that two separate items are tracked: the original page + * reference count, and also a new count of how many pin_user_pages() calls were + * made against the page. ("gup-pinned" is another term for the latter). + * + * With this scheme, pin_user_pages() becomes special: such pages are marked as + * distinct from normal pages. As such, the unpin_user_page() call (and its + * variants) must be used in order to release gup-pinned pages. + * + * Choice of value: + * + * By making GUP_PIN_COUNTING_BIAS a power of two, debugging of page reference + * counts with respect to pin_user_pages() and unpin_user_page() becomes + * simpler, due to the fact that adding an even power of two to the page + * refcount has the effect of using only the upper N bits, for the code that + * counts up using the bias value. This means that the lower bits are left for + * the exclusive use of the original code that increments and decrements by one + * (or at least, by much smaller values than the bias value). + * + * Of course, once the lower bits overflow into the upper bits (and this is + * OK, because subtraction recovers the original values), then visual inspection + * no longer suffices to directly view the separate counts. However, for normal + * applications that don't have huge page reference counts, this won't be an + * issue. + * + * Locking: the lockless algorithm described in folio_try_get_rcu() + * provides safe operation for get_user_pages(), page_mkclean() and + * other calls that race to set up page table entries. + */ +#define GUP_PIN_COUNTING_BIAS (1U << 10) + +void unpin_user_page(struct page *page); +void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages, + bool make_dirty); +void unpin_user_page_range_dirty_lock(struct page *page, unsigned long npages, + bool make_dirty); +void unpin_user_pages(struct page **pages, unsigned long npages); + +static inline bool is_cow_mapping(vm_flags_t flags) +{ + return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE; +} + +#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) +#define SECTION_IN_PAGE_FLAGS +#endif + +/* + * The identification function is mainly used by the buddy allocator for + * determining if two pages could be buddies. We are not really identifying + * the zone since we could be using the section number id if we do not have + * node id available in page flags. + * We only guarantee that it will return the same value for two combinable + * pages in a zone. + */ +static inline int page_zone_id(struct page *page) +{ + return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK; +} + +#ifdef NODE_NOT_IN_PAGE_FLAGS +extern int page_to_nid(const struct page *page); +#else +static inline int page_to_nid(const struct page *page) +{ + struct page *p = (struct page *)page; + + return (PF_POISONED_CHECK(p)->flags >> NODES_PGSHIFT) & NODES_MASK; +} +#endif + +static inline int folio_nid(const struct folio *folio) +{ + return page_to_nid(&folio->page); +} + +#ifdef CONFIG_NUMA_BALANCING +/* page access time bits needs to hold at least 4 seconds */ +#define PAGE_ACCESS_TIME_MIN_BITS 12 +#if LAST_CPUPID_SHIFT < PAGE_ACCESS_TIME_MIN_BITS +#define PAGE_ACCESS_TIME_BUCKETS \ + (PAGE_ACCESS_TIME_MIN_BITS - LAST_CPUPID_SHIFT) +#else +#define PAGE_ACCESS_TIME_BUCKETS 0 +#endif + +#define PAGE_ACCESS_TIME_MASK \ + (LAST_CPUPID_MASK << PAGE_ACCESS_TIME_BUCKETS) + +static inline int cpu_pid_to_cpupid(int cpu, int pid) +{ + return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK); +} + +static inline int cpupid_to_pid(int cpupid) +{ + return cpupid & LAST__PID_MASK; +} + +static inline int cpupid_to_cpu(int cpupid) +{ + return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK; +} + +static inline int cpupid_to_nid(int cpupid) +{ + return cpu_to_node(cpupid_to_cpu(cpupid)); +} + +static inline bool cpupid_pid_unset(int cpupid) +{ + return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK); +} + +static inline bool cpupid_cpu_unset(int cpupid) +{ + return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK); +} + +static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid) +{ + return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid); +} + +#define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid) +#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS +static inline int page_cpupid_xchg_last(struct page *page, int cpupid) +{ + return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK); +} + +static inline int page_cpupid_last(struct page *page) +{ + return page->_last_cpupid; +} +static inline void page_cpupid_reset_last(struct page *page) +{ + page->_last_cpupid = -1 & LAST_CPUPID_MASK; +} +#else +static inline int page_cpupid_last(struct page *page) +{ + return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK; +} + +extern int page_cpupid_xchg_last(struct page *page, int cpupid); + +static inline void page_cpupid_reset_last(struct page *page) +{ + page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT; +} +#endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */ + +static inline int xchg_page_access_time(struct page *page, int time) +{ + int last_time; + + last_time = page_cpupid_xchg_last(page, time >> PAGE_ACCESS_TIME_BUCKETS); + return last_time << PAGE_ACCESS_TIME_BUCKETS; +} +#else /* !CONFIG_NUMA_BALANCING */ +static inline int page_cpupid_xchg_last(struct page *page, int cpupid) +{ + return page_to_nid(page); /* XXX */ +} + +static inline int xchg_page_access_time(struct page *page, int time) +{ + return 0; +} + +static inline int page_cpupid_last(struct page *page) +{ + return page_to_nid(page); /* XXX */ +} + +static inline int cpupid_to_nid(int cpupid) +{ + return -1; +} + +static inline int cpupid_to_pid(int cpupid) +{ + return -1; +} + +static inline int cpupid_to_cpu(int cpupid) +{ + return -1; +} + +static inline int cpu_pid_to_cpupid(int nid, int pid) +{ + return -1; +} + +static inline bool cpupid_pid_unset(int cpupid) +{ + return true; +} + +static inline void page_cpupid_reset_last(struct page *page) +{ +} + +static inline bool cpupid_match_pid(struct task_struct *task, int cpupid) +{ + return false; +} +#endif /* CONFIG_NUMA_BALANCING */ + +#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) + +/* + * KASAN per-page tags are stored xor'ed with 0xff. This allows to avoid + * setting tags for all pages to native kernel tag value 0xff, as the default + * value 0x00 maps to 0xff. + */ + +static inline u8 page_kasan_tag(const struct page *page) +{ + u8 tag = 0xff; + + if (kasan_enabled()) { + tag = (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK; + tag ^= 0xff; + } + + return tag; +} + +static inline void page_kasan_tag_set(struct page *page, u8 tag) +{ + unsigned long old_flags, flags; + + if (!kasan_enabled()) + return; + + tag ^= 0xff; + old_flags = READ_ONCE(page->flags); + do { + flags = old_flags; + flags &= ~(KASAN_TAG_MASK << KASAN_TAG_PGSHIFT); + flags |= (tag & KASAN_TAG_MASK) << KASAN_TAG_PGSHIFT; + } while (unlikely(!try_cmpxchg(&page->flags, &old_flags, flags))); +} + +static inline void page_kasan_tag_reset(struct page *page) +{ + if (kasan_enabled()) + page_kasan_tag_set(page, 0xff); +} + +#else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */ + +static inline u8 page_kasan_tag(const struct page *page) +{ + return 0xff; +} + +static inline void page_kasan_tag_set(struct page *page, u8 tag) { } +static inline void page_kasan_tag_reset(struct page *page) { } + +#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */ + +static inline struct zone *page_zone(const struct page *page) +{ + return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)]; +} + +static inline pg_data_t *page_pgdat(const struct page *page) +{ + return NODE_DATA(page_to_nid(page)); +} + +static inline struct zone *folio_zone(const struct folio *folio) +{ + return page_zone(&folio->page); +} + +static inline pg_data_t *folio_pgdat(const struct folio *folio) +{ + return page_pgdat(&folio->page); +} + +#ifdef SECTION_IN_PAGE_FLAGS +static inline void set_page_section(struct page *page, unsigned long section) +{ + page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT); + page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT; +} + +static inline unsigned long page_to_section(const struct page *page) +{ + return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; +} +#endif + +/** + * folio_pfn - Return the Page Frame Number of a folio. + * @folio: The folio. + * + * A folio may contain multiple pages. The pages have consecutive + * Page Frame Numbers. + * + * Return: The Page Frame Number of the first page in the folio. + */ +static inline unsigned long folio_pfn(struct folio *folio) +{ + return page_to_pfn(&folio->page); +} + +static inline struct folio *pfn_folio(unsigned long pfn) +{ + return page_folio(pfn_to_page(pfn)); +} + +static inline atomic_t *folio_pincount_ptr(struct folio *folio) +{ + return &folio_page(folio, 1)->compound_pincount; +} + +/** + * folio_maybe_dma_pinned - Report if a folio may be pinned for DMA. + * @folio: The folio. + * + * This function checks if a folio has been pinned via a call to + * a function in the pin_user_pages() family. + * + * For small folios, the return value is partially fuzzy: false is not fuzzy, + * because it means "definitely not pinned for DMA", but true means "probably + * pinned for DMA, but possibly a false positive due to having at least + * GUP_PIN_COUNTING_BIAS worth of normal folio references". + * + * False positives are OK, because: a) it's unlikely for a folio to + * get that many refcounts, and b) all the callers of this routine are + * expected to be able to deal gracefully with a false positive. + * + * For large folios, the result will be exactly correct. That's because + * we have more tracking data available: the compound_pincount is used + * instead of the GUP_PIN_COUNTING_BIAS scheme. + * + * For more information, please see Documentation/core-api/pin_user_pages.rst. + * + * Return: True, if it is likely that the page has been "dma-pinned". + * False, if the page is definitely not dma-pinned. + */ +static inline bool folio_maybe_dma_pinned(struct folio *folio) +{ + if (folio_test_large(folio)) + return atomic_read(folio_pincount_ptr(folio)) > 0; + + /* + * folio_ref_count() is signed. If that refcount overflows, then + * folio_ref_count() returns a negative value, and callers will avoid + * further incrementing the refcount. + * + * Here, for that overflow case, use the sign bit to count a little + * bit higher via unsigned math, and thus still get an accurate result. + */ + return ((unsigned int)folio_ref_count(folio)) >= + GUP_PIN_COUNTING_BIAS; +} + +static inline bool page_maybe_dma_pinned(struct page *page) +{ + return folio_maybe_dma_pinned(page_folio(page)); +} + +/* + * This should most likely only be called during fork() to see whether we + * should break the cow immediately for an anon page on the src mm. + * + * The caller has to hold the PT lock and the vma->vm_mm->->write_protect_seq. + */ +static inline bool page_needs_cow_for_dma(struct vm_area_struct *vma, + struct page *page) +{ + VM_BUG_ON(!(raw_read_seqcount(&vma->vm_mm->write_protect_seq) & 1)); + + if (!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags)) + return false; + + return page_maybe_dma_pinned(page); +} + +/* MIGRATE_CMA and ZONE_MOVABLE do not allow pin pages */ +#ifdef CONFIG_MIGRATION +static inline bool is_longterm_pinnable_page(struct page *page) +{ +#ifdef CONFIG_CMA + int mt = get_pageblock_migratetype(page); + + if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE) + return false; +#endif + /* The zero page may always be pinned */ + if (is_zero_pfn(page_to_pfn(page))) + return true; + + /* Coherent device memory must always allow eviction. */ + if (is_device_coherent_page(page)) + return false; + + /* Otherwise, non-movable zone pages can be pinned. */ + return !is_zone_movable_page(page); +} +#else +static inline bool is_longterm_pinnable_page(struct page *page) +{ + return true; +} +#endif + +static inline bool folio_is_longterm_pinnable(struct folio *folio) +{ + return is_longterm_pinnable_page(&folio->page); +} + +static inline void set_page_zone(struct page *page, enum zone_type zone) +{ + page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); + page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; +} + +static inline void set_page_node(struct page *page, unsigned long node) +{ + page->flags &= ~(NODES_MASK << NODES_PGSHIFT); + page->flags |= (node & NODES_MASK) << NODES_PGSHIFT; +} + +static inline void set_page_links(struct page *page, enum zone_type zone, + unsigned long node, unsigned long pfn) +{ + set_page_zone(page, zone); + set_page_node(page, node); +#ifdef SECTION_IN_PAGE_FLAGS + set_page_section(page, pfn_to_section_nr(pfn)); +#endif +} + +/** + * folio_nr_pages - The number of pages in the folio. + * @folio: The folio. + * + * Return: A positive power of two. + */ +static inline long folio_nr_pages(struct folio *folio) +{ + if (!folio_test_large(folio)) + return 1; +#ifdef CONFIG_64BIT + return folio->_folio_nr_pages; +#else + return 1L << folio->_folio_order; +#endif +} + +/** + * folio_next - Move to the next physical folio. + * @folio: The folio we're currently operating on. + * + * If you have physically contiguous memory which may span more than + * one folio (eg a &struct bio_vec), use this function to move from one + * folio to the next. Do not use it if the memory is only virtually + * contiguous as the folios are almost certainly not adjacent to each + * other. This is the folio equivalent to writing ``page++``. + * + * Context: We assume that the folios are refcounted and/or locked at a + * higher level and do not adjust the reference counts. + * Return: The next struct folio. + */ +static inline struct folio *folio_next(struct folio *folio) +{ + return (struct folio *)folio_page(folio, folio_nr_pages(folio)); +} + +/** + * folio_shift - The size of the memory described by this folio. + * @folio: The folio. + * + * A folio represents a number of bytes which is a power-of-two in size. + * This function tells you which power-of-two the folio is. See also + * folio_size() and folio_order(). + * + * Context: The caller should have a reference on the folio to prevent + * it from being split. It is not necessary for the folio to be locked. + * Return: The base-2 logarithm of the size of this folio. + */ +static inline unsigned int folio_shift(struct folio *folio) +{ + return PAGE_SHIFT + folio_order(folio); +} + +/** + * folio_size - The number of bytes in a folio. + * @folio: The folio. + * + * Context: The caller should have a reference on the folio to prevent + * it from being split. It is not necessary for the folio to be locked. + * Return: The number of bytes in this folio. + */ +static inline size_t folio_size(struct folio *folio) +{ + return PAGE_SIZE << folio_order(folio); +} + +/** + * folio_estimated_sharers - Estimate the number of sharers of a folio. + * @folio: The folio. + * + * folio_estimated_sharers() aims to serve as a function to efficiently + * estimate the number of processes sharing a folio. This is done by + * looking at the precise mapcount of the first subpage in the folio, and + * assuming the other subpages are the same. This may not be true for large + * folios. If you want exact mapcounts for exact calculations, look at + * page_mapcount() or folio_total_mapcount(). + * + * Return: The estimated number of processes sharing a folio. + */ +static inline int folio_estimated_sharers(struct folio *folio) +{ + return page_mapcount(folio_page(folio, 0)); +} + + +#ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE +static inline int arch_make_page_accessible(struct page *page) +{ + return 0; +} +#endif + +#ifndef HAVE_ARCH_MAKE_FOLIO_ACCESSIBLE +static inline int arch_make_folio_accessible(struct folio *folio) +{ + int ret; + long i, nr = folio_nr_pages(folio); + + for (i = 0; i < nr; i++) { + ret = arch_make_page_accessible(folio_page(folio, i)); + if (ret) + break; + } + + return ret; +} +#endif + +/* + * Some inline functions in vmstat.h depend on page_zone() + */ +#include <linux/vmstat.h> + +static __always_inline void *lowmem_page_address(const struct page *page) +{ + return page_to_virt(page); +} + +#if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) +#define HASHED_PAGE_VIRTUAL +#endif + +#if defined(WANT_PAGE_VIRTUAL) +static inline void *page_address(const struct page *page) +{ + return page->virtual; +} +static inline void set_page_address(struct page *page, void *address) +{ + page->virtual = address; +} +#define page_address_init() do { } while(0) +#endif + +#if defined(HASHED_PAGE_VIRTUAL) +void *page_address(const struct page *page); +void set_page_address(struct page *page, void *virtual); +void page_address_init(void); +#endif + +#if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL) +#define page_address(page) lowmem_page_address(page) +#define set_page_address(page, address) do { } while(0) +#define page_address_init() do { } while(0) +#endif + +static inline void *folio_address(const struct folio *folio) +{ + return page_address(&folio->page); +} + +extern void *page_rmapping(struct page *page); +extern pgoff_t __page_file_index(struct page *page); + +/* + * Return the pagecache index of the passed page. Regular pagecache pages + * use ->index whereas swapcache pages use swp_offset(->private) + */ +static inline pgoff_t page_index(struct page *page) +{ + if (unlikely(PageSwapCache(page))) + return __page_file_index(page); + return page->index; +} + +bool page_mapped(struct page *page); +bool folio_mapped(struct folio *folio); + +/* + * Return true only if the page has been allocated with + * ALLOC_NO_WATERMARKS and the low watermark was not + * met implying that the system is under some pressure. + */ +static inline bool page_is_pfmemalloc(const struct page *page) +{ + /* + * lru.next has bit 1 set if the page is allocated from the + * pfmemalloc reserves. Callers may simply overwrite it if + * they do not need to preserve that information. + */ + return (uintptr_t)page->lru.next & BIT(1); +} + +/* + * Only to be called by the page allocator on a freshly allocated + * page. + */ +static inline void set_page_pfmemalloc(struct page *page) +{ + page->lru.next = (void *)BIT(1); +} + +static inline void clear_page_pfmemalloc(struct page *page) +{ + page->lru.next = NULL; +} + +/* + * Can be called by the pagefault handler when it gets a VM_FAULT_OOM. + */ +extern void pagefault_out_of_memory(void); + +#define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) +#define offset_in_thp(page, p) ((unsigned long)(p) & (thp_size(page) - 1)) +#define offset_in_folio(folio, p) ((unsigned long)(p) & (folio_size(folio) - 1)) + +/* + * Flags passed to show_mem() and show_free_areas() to suppress output in + * various contexts. + */ +#define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */ + +extern void __show_free_areas(unsigned int flags, nodemask_t *nodemask, int max_zone_idx); +static void __maybe_unused show_free_areas(unsigned int flags, nodemask_t *nodemask) +{ + __show_free_areas(flags, nodemask, MAX_NR_ZONES - 1); +} + +/* + * Parameter block passed down to zap_pte_range in exceptional cases. + */ +struct zap_details { + struct folio *single_folio; /* Locked folio to be unmapped */ + bool even_cows; /* Zap COWed private pages too? */ + zap_flags_t zap_flags; /* Extra flags for zapping */ +}; + +/* + * Whether to drop the pte markers, for example, the uffd-wp information for + * file-backed memory. This should only be specified when we will completely + * drop the page in the mm, either by truncation or unmapping of the vma. By + * default, the flag is not set. + */ +#define ZAP_FLAG_DROP_MARKER ((__force zap_flags_t) BIT(0)) +/* Set in unmap_vmas() to indicate a final unmap call. Only used by hugetlb */ +#define ZAP_FLAG_UNMAP ((__force zap_flags_t) BIT(1)) + +#ifdef CONFIG_MMU +extern bool can_do_mlock(void); +#else +static inline bool can_do_mlock(void) { return false; } +#endif +extern int user_shm_lock(size_t, struct ucounts *); +extern void user_shm_unlock(size_t, struct ucounts *); + +struct folio *vm_normal_folio(struct vm_area_struct *vma, unsigned long addr, + pte_t pte); +struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, + pte_t pte); +struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr, + pmd_t pmd); + +void zap_vma_ptes(struct vm_area_struct *vma, unsigned long address, + unsigned long size); +void zap_page_range(struct vm_area_struct *vma, unsigned long address, + unsigned long size); +void zap_page_range_single(struct vm_area_struct *vma, unsigned long address, + unsigned long size, struct zap_details *details); +void unmap_vmas(struct mmu_gather *tlb, struct maple_tree *mt, + struct vm_area_struct *start_vma, unsigned long start, + unsigned long end); + +struct mmu_notifier_range; + +void free_pgd_range(struct mmu_gather *tlb, unsigned long addr, + unsigned long end, unsigned long floor, unsigned long ceiling); +int +copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma); +int follow_pte(struct mm_struct *mm, unsigned long address, + pte_t **ptepp, spinlock_t **ptlp); +int follow_pfn(struct vm_area_struct *vma, unsigned long address, + unsigned long *pfn); +int follow_phys(struct vm_area_struct *vma, unsigned long address, + unsigned int flags, unsigned long *prot, resource_size_t *phys); +int generic_access_phys(struct vm_area_struct *vma, unsigned long addr, + void *buf, int len, int write); + +extern void truncate_pagecache(struct inode *inode, loff_t new); +extern void truncate_setsize(struct inode *inode, loff_t newsize); +void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to); +void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end); +int generic_error_remove_page(struct address_space *mapping, struct page *page); + +struct vm_area_struct *lock_mm_and_find_vma(struct mm_struct *mm, + unsigned long address, struct pt_regs *regs); + +#ifdef CONFIG_MMU +extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma, + unsigned long address, unsigned int flags, + struct pt_regs *regs); +extern int fixup_user_fault(struct mm_struct *mm, + unsigned long address, unsigned int fault_flags, + bool *unlocked); +void unmap_mapping_pages(struct address_space *mapping, + pgoff_t start, pgoff_t nr, bool even_cows); +void unmap_mapping_range(struct address_space *mapping, + loff_t const holebegin, loff_t const holelen, int even_cows); +#else +static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma, + unsigned long address, unsigned int flags, + struct pt_regs *regs) +{ + /* should never happen if there's no MMU */ + BUG(); + return VM_FAULT_SIGBUS; +} +static inline int fixup_user_fault(struct mm_struct *mm, unsigned long address, + unsigned int fault_flags, bool *unlocked) +{ + /* should never happen if there's no MMU */ + BUG(); + return -EFAULT; +} +static inline void unmap_mapping_pages(struct address_space *mapping, + pgoff_t start, pgoff_t nr, bool even_cows) { } +static inline void unmap_mapping_range(struct address_space *mapping, + loff_t const holebegin, loff_t const holelen, int even_cows) { } +#endif + +static inline void unmap_shared_mapping_range(struct address_space *mapping, + loff_t const holebegin, loff_t const holelen) +{ + unmap_mapping_range(mapping, holebegin, holelen, 0); +} + +extern int access_process_vm(struct task_struct *tsk, unsigned long addr, + void *buf, int len, unsigned int gup_flags); +extern int access_remote_vm(struct mm_struct *mm, unsigned long addr, + void *buf, int len, unsigned int gup_flags); +extern int __access_remote_vm(struct mm_struct *mm, unsigned long addr, + void *buf, int len, unsigned int gup_flags); + +long get_user_pages_remote(struct mm_struct *mm, + unsigned long start, unsigned long nr_pages, + unsigned int gup_flags, struct page **pages, + struct vm_area_struct **vmas, int *locked); +long pin_user_pages_remote(struct mm_struct *mm, + unsigned long start, unsigned long nr_pages, + unsigned int gup_flags, struct page **pages, + struct vm_area_struct **vmas, int *locked); +long get_user_pages(unsigned long start, unsigned long nr_pages, + unsigned int gup_flags, struct page **pages, + struct vm_area_struct **vmas); +long pin_user_pages(unsigned long start, unsigned long nr_pages, + unsigned int gup_flags, struct page **pages, + struct vm_area_struct **vmas); +long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, + struct page **pages, unsigned int gup_flags); +long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages, + struct page **pages, unsigned int gup_flags); + +int get_user_pages_fast(unsigned long start, int nr_pages, + unsigned int gup_flags, struct page **pages); +int pin_user_pages_fast(unsigned long start, int nr_pages, + unsigned int gup_flags, struct page **pages); + +int account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc); +int __account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc, + struct task_struct *task, bool bypass_rlim); + +struct kvec; +int get_kernel_pages(const struct kvec *iov, int nr_pages, int write, + struct page **pages); +struct page *get_dump_page(unsigned long addr); + +bool folio_mark_dirty(struct folio *folio); +bool set_page_dirty(struct page *page); +int set_page_dirty_lock(struct page *page); + +int get_cmdline(struct task_struct *task, char *buffer, int buflen); + +extern unsigned long move_page_tables(struct vm_area_struct *vma, + unsigned long old_addr, struct vm_area_struct *new_vma, + unsigned long new_addr, unsigned long len, + bool need_rmap_locks); + +/* + * Flags used by change_protection(). For now we make it a bitmap so + * that we can pass in multiple flags just like parameters. However + * for now all the callers are only use one of the flags at the same + * time. + */ +/* + * Whether we should manually check if we can map individual PTEs writable, + * because something (e.g., COW, uffd-wp) blocks that from happening for all + * PTEs automatically in a writable mapping. + */ +#define MM_CP_TRY_CHANGE_WRITABLE (1UL << 0) +/* Whether this protection change is for NUMA hints */ +#define MM_CP_PROT_NUMA (1UL << 1) +/* Whether this change is for write protecting */ +#define MM_CP_UFFD_WP (1UL << 2) /* do wp */ +#define MM_CP_UFFD_WP_RESOLVE (1UL << 3) /* Resolve wp */ +#define MM_CP_UFFD_WP_ALL (MM_CP_UFFD_WP | \ + MM_CP_UFFD_WP_RESOLVE) + +extern unsigned long change_protection(struct mmu_gather *tlb, + struct vm_area_struct *vma, unsigned long start, + unsigned long end, pgprot_t newprot, + unsigned long cp_flags); +extern int mprotect_fixup(struct mmu_gather *tlb, struct vm_area_struct *vma, + struct vm_area_struct **pprev, unsigned long start, + unsigned long end, unsigned long newflags); + +/* + * doesn't attempt to fault and will return short. + */ +int get_user_pages_fast_only(unsigned long start, int nr_pages, + unsigned int gup_flags, struct page **pages); +int pin_user_pages_fast_only(unsigned long start, int nr_pages, + unsigned int gup_flags, struct page **pages); + +static inline bool get_user_page_fast_only(unsigned long addr, + unsigned int gup_flags, struct page **pagep) +{ + return get_user_pages_fast_only(addr, 1, gup_flags, pagep) == 1; +} +/* + * per-process(per-mm_struct) statistics. + */ +static inline unsigned long get_mm_counter(struct mm_struct *mm, int member) +{ + long val = atomic_long_read(&mm->rss_stat.count[member]); + +#ifdef SPLIT_RSS_COUNTING + /* + * counter is updated in asynchronous manner and may go to minus. + * But it's never be expected number for users. + */ + if (val < 0) + val = 0; +#endif + return (unsigned long)val; +} + +void mm_trace_rss_stat(struct mm_struct *mm, int member, long count); + +static inline void add_mm_counter(struct mm_struct *mm, int member, long value) +{ + long count = atomic_long_add_return(value, &mm->rss_stat.count[member]); + + mm_trace_rss_stat(mm, member, count); +} + +static inline void inc_mm_counter(struct mm_struct *mm, int member) +{ + long count = atomic_long_inc_return(&mm->rss_stat.count[member]); + + mm_trace_rss_stat(mm, member, count); +} + +static inline void dec_mm_counter(struct mm_struct *mm, int member) +{ + long count = atomic_long_dec_return(&mm->rss_stat.count[member]); + + mm_trace_rss_stat(mm, member, count); +} + +/* Optimized variant when page is already known not to be PageAnon */ +static inline int mm_counter_file(struct page *page) +{ + if (PageSwapBacked(page)) + return MM_SHMEMPAGES; + return MM_FILEPAGES; +} + +static inline int mm_counter(struct page *page) +{ + if (PageAnon(page)) + return MM_ANONPAGES; + return mm_counter_file(page); +} + +static inline unsigned long get_mm_rss(struct mm_struct *mm) +{ + return get_mm_counter(mm, MM_FILEPAGES) + + get_mm_counter(mm, MM_ANONPAGES) + + get_mm_counter(mm, MM_SHMEMPAGES); +} + +static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm) +{ + return max(mm->hiwater_rss, get_mm_rss(mm)); +} + +static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm) +{ + return max(mm->hiwater_vm, mm->total_vm); +} + +static inline void update_hiwater_rss(struct mm_struct *mm) +{ + unsigned long _rss = get_mm_rss(mm); + + if ((mm)->hiwater_rss < _rss) + (mm)->hiwater_rss = _rss; +} + +static inline void update_hiwater_vm(struct mm_struct *mm) +{ + if (mm->hiwater_vm < mm->total_vm) + mm->hiwater_vm = mm->total_vm; +} + +static inline void reset_mm_hiwater_rss(struct mm_struct *mm) +{ + mm->hiwater_rss = get_mm_rss(mm); +} + +static inline void setmax_mm_hiwater_rss(unsigned long *maxrss, + struct mm_struct *mm) +{ + unsigned long hiwater_rss = get_mm_hiwater_rss(mm); + + if (*maxrss < hiwater_rss) + *maxrss = hiwater_rss; +} + +#if defined(SPLIT_RSS_COUNTING) +void sync_mm_rss(struct mm_struct *mm); +#else +static inline void sync_mm_rss(struct mm_struct *mm) +{ +} +#endif + +#ifndef CONFIG_ARCH_HAS_PTE_SPECIAL +static inline int pte_special(pte_t pte) +{ + return 0; +} + +static inline pte_t pte_mkspecial(pte_t pte) +{ + return pte; +} +#endif + +#ifndef CONFIG_ARCH_HAS_PTE_DEVMAP +static inline int pte_devmap(pte_t pte) +{ + return 0; +} +#endif + +int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot); + +extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr, + spinlock_t **ptl); +static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, + spinlock_t **ptl) +{ + pte_t *ptep; + __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl)); + return ptep; +} + +#ifdef __PAGETABLE_P4D_FOLDED +static inline int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, + unsigned long address) +{ + return 0; +} +#else +int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); +#endif + +#if defined(__PAGETABLE_PUD_FOLDED) || !defined(CONFIG_MMU) +static inline int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, + unsigned long address) +{ + return 0; +} +static inline void mm_inc_nr_puds(struct mm_struct *mm) {} +static inline void mm_dec_nr_puds(struct mm_struct *mm) {} + +#else +int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address); + +static inline void mm_inc_nr_puds(struct mm_struct *mm) +{ + if (mm_pud_folded(mm)) + return; + atomic_long_add(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes); +} + +static inline void mm_dec_nr_puds(struct mm_struct *mm) +{ + if (mm_pud_folded(mm)) + return; + atomic_long_sub(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes); +} +#endif + +#if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU) +static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud, + unsigned long address) +{ + return 0; +} + +static inline void mm_inc_nr_pmds(struct mm_struct *mm) {} +static inline void mm_dec_nr_pmds(struct mm_struct *mm) {} + +#else +int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); + +static inline void mm_inc_nr_pmds(struct mm_struct *mm) +{ + if (mm_pmd_folded(mm)) + return; + atomic_long_add(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes); +} + +static inline void mm_dec_nr_pmds(struct mm_struct *mm) +{ + if (mm_pmd_folded(mm)) + return; + atomic_long_sub(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes); +} +#endif + +#ifdef CONFIG_MMU +static inline void mm_pgtables_bytes_init(struct mm_struct *mm) +{ + atomic_long_set(&mm->pgtables_bytes, 0); +} + +static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm) +{ + return atomic_long_read(&mm->pgtables_bytes); +} + +static inline void mm_inc_nr_ptes(struct mm_struct *mm) +{ + atomic_long_add(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes); +} + +static inline void mm_dec_nr_ptes(struct mm_struct *mm) +{ + atomic_long_sub(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes); +} +#else + +static inline void mm_pgtables_bytes_init(struct mm_struct *mm) {} +static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm) +{ + return 0; +} + +static inline void mm_inc_nr_ptes(struct mm_struct *mm) {} +static inline void mm_dec_nr_ptes(struct mm_struct *mm) {} +#endif + +int __pte_alloc(struct mm_struct *mm, pmd_t *pmd); +int __pte_alloc_kernel(pmd_t *pmd); + +#if defined(CONFIG_MMU) + +static inline p4d_t *p4d_alloc(struct mm_struct *mm, pgd_t *pgd, + unsigned long address) +{ + return (unlikely(pgd_none(*pgd)) && __p4d_alloc(mm, pgd, address)) ? + NULL : p4d_offset(pgd, address); +} + +static inline pud_t *pud_alloc(struct mm_struct *mm, p4d_t *p4d, + unsigned long address) +{ + return (unlikely(p4d_none(*p4d)) && __pud_alloc(mm, p4d, address)) ? + NULL : pud_offset(p4d, address); +} + +static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) +{ + return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))? + NULL: pmd_offset(pud, address); +} +#endif /* CONFIG_MMU */ + +#if USE_SPLIT_PTE_PTLOCKS +#if ALLOC_SPLIT_PTLOCKS +void __init ptlock_cache_init(void); +extern bool ptlock_alloc(struct page *page); +extern void ptlock_free(struct page *page); + +static inline spinlock_t *ptlock_ptr(struct page *page) +{ + return page->ptl; +} +#else /* ALLOC_SPLIT_PTLOCKS */ +static inline void ptlock_cache_init(void) +{ +} + +static inline bool ptlock_alloc(struct page *page) +{ + return true; +} + +static inline void ptlock_free(struct page *page) +{ +} + +static inline spinlock_t *ptlock_ptr(struct page *page) +{ + return &page->ptl; +} +#endif /* ALLOC_SPLIT_PTLOCKS */ + +static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd) +{ + return ptlock_ptr(pmd_page(*pmd)); +} + +static inline bool ptlock_init(struct page *page) +{ + /* + * prep_new_page() initialize page->private (and therefore page->ptl) + * with 0. Make sure nobody took it in use in between. + * + * It can happen if arch try to use slab for page table allocation: + * slab code uses page->slab_cache, which share storage with page->ptl. + */ + VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page); + if (!ptlock_alloc(page)) + return false; + spin_lock_init(ptlock_ptr(page)); + return true; +} + +#else /* !USE_SPLIT_PTE_PTLOCKS */ +/* + * We use mm->page_table_lock to guard all pagetable pages of the mm. + */ +static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd) +{ + return &mm->page_table_lock; +} +static inline void ptlock_cache_init(void) {} +static inline bool ptlock_init(struct page *page) { return true; } +static inline void ptlock_free(struct page *page) {} +#endif /* USE_SPLIT_PTE_PTLOCKS */ + +static inline void pgtable_init(void) +{ + ptlock_cache_init(); + pgtable_cache_init(); +} + +static inline bool pgtable_pte_page_ctor(struct page *page) +{ + if (!ptlock_init(page)) + return false; + __SetPageTable(page); + inc_lruvec_page_state(page, NR_PAGETABLE); + return true; +} + +static inline void pgtable_pte_page_dtor(struct page *page) +{ + ptlock_free(page); + __ClearPageTable(page); + dec_lruvec_page_state(page, NR_PAGETABLE); +} + +#define pte_offset_map_lock(mm, pmd, address, ptlp) \ +({ \ + spinlock_t *__ptl = pte_lockptr(mm, pmd); \ + pte_t *__pte = pte_offset_map(pmd, address); \ + *(ptlp) = __ptl; \ + spin_lock(__ptl); \ + __pte; \ +}) + +#define pte_unmap_unlock(pte, ptl) do { \ + spin_unlock(ptl); \ + pte_unmap(pte); \ +} while (0) + +#define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd)) + +#define pte_alloc_map(mm, pmd, address) \ + (pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address)) + +#define pte_alloc_map_lock(mm, pmd, address, ptlp) \ + (pte_alloc(mm, pmd) ? \ + NULL : pte_offset_map_lock(mm, pmd, address, ptlp)) + +#define pte_alloc_kernel(pmd, address) \ + ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \ + NULL: pte_offset_kernel(pmd, address)) + +#if USE_SPLIT_PMD_PTLOCKS + +static struct page *pmd_to_page(pmd_t *pmd) +{ + unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); + return virt_to_page((void *)((unsigned long) pmd & mask)); +} + +static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) +{ + return ptlock_ptr(pmd_to_page(pmd)); +} + +static inline bool pmd_ptlock_init(struct page *page) +{ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + page->pmd_huge_pte = NULL; +#endif + return ptlock_init(page); +} + +static inline void pmd_ptlock_free(struct page *page) +{ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + VM_BUG_ON_PAGE(page->pmd_huge_pte, page); +#endif + ptlock_free(page); +} + +#define pmd_huge_pte(mm, pmd) (pmd_to_page(pmd)->pmd_huge_pte) + +#else + +static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) +{ + return &mm->page_table_lock; +} + +static inline bool pmd_ptlock_init(struct page *page) { return true; } +static inline void pmd_ptlock_free(struct page *page) {} + +#define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte) + +#endif + +static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd) +{ + spinlock_t *ptl = pmd_lockptr(mm, pmd); + spin_lock(ptl); + return ptl; +} + +static inline bool pgtable_pmd_page_ctor(struct page *page) +{ + if (!pmd_ptlock_init(page)) + return false; + __SetPageTable(page); + inc_lruvec_page_state(page, NR_PAGETABLE); + return true; +} + +static inline void pgtable_pmd_page_dtor(struct page *page) +{ + pmd_ptlock_free(page); + __ClearPageTable(page); + dec_lruvec_page_state(page, NR_PAGETABLE); +} + +/* + * No scalability reason to split PUD locks yet, but follow the same pattern + * as the PMD locks to make it easier if we decide to. The VM should not be + * considered ready to switch to split PUD locks yet; there may be places + * which need to be converted from page_table_lock. + */ +static inline spinlock_t *pud_lockptr(struct mm_struct *mm, pud_t *pud) +{ + return &mm->page_table_lock; +} + +static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud) +{ + spinlock_t *ptl = pud_lockptr(mm, pud); + + spin_lock(ptl); + return ptl; +} + +extern void __init pagecache_init(void); +extern void free_initmem(void); + +/* + * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK) + * into the buddy system. The freed pages will be poisoned with pattern + * "poison" if it's within range [0, UCHAR_MAX]. + * Return pages freed into the buddy system. + */ +extern unsigned long free_reserved_area(void *start, void *end, + int poison, const char *s); + +extern void adjust_managed_page_count(struct page *page, long count); +extern void mem_init_print_info(void); + +extern void reserve_bootmem_region(phys_addr_t start, phys_addr_t end); + +/* Free the reserved page into the buddy system, so it gets managed. */ +static inline void free_reserved_page(struct page *page) +{ + ClearPageReserved(page); + init_page_count(page); + __free_page(page); + adjust_managed_page_count(page, 1); +} +#define free_highmem_page(page) free_reserved_page(page) + +static inline void mark_page_reserved(struct page *page) +{ + SetPageReserved(page); + adjust_managed_page_count(page, -1); +} + +/* + * Default method to free all the __init memory into the buddy system. + * The freed pages will be poisoned with pattern "poison" if it's within + * range [0, UCHAR_MAX]. + * Return pages freed into the buddy system. + */ +static inline unsigned long free_initmem_default(int poison) +{ + extern char __init_begin[], __init_end[]; + + return free_reserved_area(&__init_begin, &__init_end, + poison, "unused kernel image (initmem)"); +} + +static inline unsigned long get_num_physpages(void) +{ + int nid; + unsigned long phys_pages = 0; + + for_each_online_node(nid) + phys_pages += node_present_pages(nid); + + return phys_pages; +} + +/* + * Using memblock node mappings, an architecture may initialise its + * zones, allocate the backing mem_map and account for memory holes in an + * architecture independent manner. + * + * An architecture is expected to register range of page frames backed by + * physical memory with memblock_add[_node]() before calling + * free_area_init() passing in the PFN each zone ends at. At a basic + * usage, an architecture is expected to do something like + * + * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn, + * max_highmem_pfn}; + * for_each_valid_physical_page_range() + * memblock_add_node(base, size, nid, MEMBLOCK_NONE) + * free_area_init(max_zone_pfns); + */ +void free_area_init(unsigned long *max_zone_pfn); +unsigned long node_map_pfn_alignment(void); +unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn, + unsigned long end_pfn); +extern unsigned long absent_pages_in_range(unsigned long start_pfn, + unsigned long end_pfn); +extern void get_pfn_range_for_nid(unsigned int nid, + unsigned long *start_pfn, unsigned long *end_pfn); + +#ifndef CONFIG_NUMA +static inline int early_pfn_to_nid(unsigned long pfn) +{ + return 0; +} +#else +/* please see mm/page_alloc.c */ +extern int __meminit early_pfn_to_nid(unsigned long pfn); +#endif + +extern void set_dma_reserve(unsigned long new_dma_reserve); +extern void memmap_init_range(unsigned long, int, unsigned long, + unsigned long, unsigned long, enum meminit_context, + struct vmem_altmap *, int migratetype); +extern void setup_per_zone_wmarks(void); +extern void calculate_min_free_kbytes(void); +extern int __meminit init_per_zone_wmark_min(void); +extern void mem_init(void); +extern void __init mmap_init(void); + +extern void __show_mem(unsigned int flags, nodemask_t *nodemask, int max_zone_idx); +static inline void show_mem(unsigned int flags, nodemask_t *nodemask) +{ + __show_mem(flags, nodemask, MAX_NR_ZONES - 1); +} +extern long si_mem_available(void); +extern void si_meminfo(struct sysinfo * val); +extern void si_meminfo_node(struct sysinfo *val, int nid); +#ifdef __HAVE_ARCH_RESERVED_KERNEL_PAGES +extern unsigned long arch_reserved_kernel_pages(void); +#endif + +extern __printf(3, 4) +void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...); + +extern void setup_per_cpu_pageset(void); + +/* page_alloc.c */ +extern int min_free_kbytes; +extern int watermark_boost_factor; +extern int watermark_scale_factor; +extern bool arch_has_descending_max_zone_pfns(void); + +/* nommu.c */ +extern atomic_long_t mmap_pages_allocated; +extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t); + +/* interval_tree.c */ +void vma_interval_tree_insert(struct vm_area_struct *node, + struct rb_root_cached *root); +void vma_interval_tree_insert_after(struct vm_area_struct *node, + struct vm_area_struct *prev, + struct rb_root_cached *root); +void vma_interval_tree_remove(struct vm_area_struct *node, + struct rb_root_cached *root); +struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root_cached *root, + unsigned long start, unsigned long last); +struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node, + unsigned long start, unsigned long last); + +#define vma_interval_tree_foreach(vma, root, start, last) \ + for (vma = vma_interval_tree_iter_first(root, start, last); \ + vma; vma = vma_interval_tree_iter_next(vma, start, last)) + +void anon_vma_interval_tree_insert(struct anon_vma_chain *node, + struct rb_root_cached *root); +void anon_vma_interval_tree_remove(struct anon_vma_chain *node, + struct rb_root_cached *root); +struct anon_vma_chain * +anon_vma_interval_tree_iter_first(struct rb_root_cached *root, + unsigned long start, unsigned long last); +struct anon_vma_chain *anon_vma_interval_tree_iter_next( + struct anon_vma_chain *node, unsigned long start, unsigned long last); +#ifdef CONFIG_DEBUG_VM_RB +void anon_vma_interval_tree_verify(struct anon_vma_chain *node); +#endif + +#define anon_vma_interval_tree_foreach(avc, root, start, last) \ + for (avc = anon_vma_interval_tree_iter_first(root, start, last); \ + avc; avc = anon_vma_interval_tree_iter_next(avc, start, last)) + +/* mmap.c */ +extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin); +extern int __vma_adjust(struct vm_area_struct *vma, unsigned long start, + unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert, + struct vm_area_struct *expand); +static inline int vma_adjust(struct vm_area_struct *vma, unsigned long start, + unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert) +{ + return __vma_adjust(vma, start, end, pgoff, insert, NULL); +} +extern struct vm_area_struct *vma_merge(struct mm_struct *, + struct vm_area_struct *prev, unsigned long addr, unsigned long end, + unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t, + struct mempolicy *, struct vm_userfaultfd_ctx, struct anon_vma_name *); +extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *); +extern int __split_vma(struct mm_struct *, struct vm_area_struct *, + unsigned long addr, int new_below); +extern int split_vma(struct mm_struct *, struct vm_area_struct *, + unsigned long addr, int new_below); +extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *); +extern void unlink_file_vma(struct vm_area_struct *); +extern struct vm_area_struct *copy_vma(struct vm_area_struct **, + unsigned long addr, unsigned long len, pgoff_t pgoff, + bool *need_rmap_locks); +extern void exit_mmap(struct mm_struct *); + +void vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas); +void vma_mas_remove(struct vm_area_struct *vma, struct ma_state *mas); + +static inline int check_data_rlimit(unsigned long rlim, + unsigned long new, + unsigned long start, + unsigned long end_data, + unsigned long start_data) +{ + if (rlim < RLIM_INFINITY) { + if (((new - start) + (end_data - start_data)) > rlim) + return -ENOSPC; + } + + return 0; +} + +extern int mm_take_all_locks(struct mm_struct *mm); +extern void mm_drop_all_locks(struct mm_struct *mm); + +extern int set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file); +extern int replace_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file); +extern struct file *get_mm_exe_file(struct mm_struct *mm); +extern struct file *get_task_exe_file(struct task_struct *task); + +extern bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long npages); +extern void vm_stat_account(struct mm_struct *, vm_flags_t, long npages); + +extern bool vma_is_special_mapping(const struct vm_area_struct *vma, + const struct vm_special_mapping *sm); +extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm, + unsigned long addr, unsigned long len, + unsigned long flags, + const struct vm_special_mapping *spec); +/* This is an obsolete alternative to _install_special_mapping. */ +extern int install_special_mapping(struct mm_struct *mm, + unsigned long addr, unsigned long len, + unsigned long flags, struct page **pages); + +unsigned long randomize_stack_top(unsigned long stack_top); +unsigned long randomize_page(unsigned long start, unsigned long range); + +extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); + +extern unsigned long mmap_region(struct file *file, unsigned long addr, + unsigned long len, vm_flags_t vm_flags, unsigned long pgoff, + struct list_head *uf); +extern unsigned long do_mmap(struct file *file, unsigned long addr, + unsigned long len, unsigned long prot, unsigned long flags, + unsigned long pgoff, unsigned long *populate, struct list_head *uf); +extern int do_mas_munmap(struct ma_state *mas, struct mm_struct *mm, + unsigned long start, size_t len, struct list_head *uf, + bool downgrade); +extern int do_munmap(struct mm_struct *, unsigned long, size_t, + struct list_head *uf); +extern int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior); + +#ifdef CONFIG_MMU +extern int __mm_populate(unsigned long addr, unsigned long len, + int ignore_errors); +static inline void mm_populate(unsigned long addr, unsigned long len) +{ + /* Ignore errors */ + (void) __mm_populate(addr, len, 1); +} +#else +static inline void mm_populate(unsigned long addr, unsigned long len) {} +#endif + +/* These take the mm semaphore themselves */ +extern int __must_check vm_brk(unsigned long, unsigned long); +extern int __must_check vm_brk_flags(unsigned long, unsigned long, unsigned long); +extern int vm_munmap(unsigned long, size_t); +extern unsigned long __must_check vm_mmap(struct file *, unsigned long, + unsigned long, unsigned long, + unsigned long, unsigned long); + +struct vm_unmapped_area_info { +#define VM_UNMAPPED_AREA_TOPDOWN 1 + unsigned long flags; + unsigned long length; + unsigned long low_limit; + unsigned long high_limit; + unsigned long align_mask; + unsigned long align_offset; +}; + +extern unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info); + +/* truncate.c */ +extern void truncate_inode_pages(struct address_space *, loff_t); +extern void truncate_inode_pages_range(struct address_space *, + loff_t lstart, loff_t lend); +extern void truncate_inode_pages_final(struct address_space *); + +/* generic vm_area_ops exported for stackable file systems */ +extern vm_fault_t filemap_fault(struct vm_fault *vmf); +extern vm_fault_t filemap_map_pages(struct vm_fault *vmf, + pgoff_t start_pgoff, pgoff_t end_pgoff); +extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf); + +extern unsigned long stack_guard_gap; +/* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */ +int expand_stack_locked(struct vm_area_struct *vma, unsigned long address); +struct vm_area_struct *expand_stack(struct mm_struct * mm, unsigned long addr); + +/* CONFIG_STACK_GROWSUP still needs to grow downwards at some places */ +int expand_downwards(struct vm_area_struct *vma, unsigned long address); + +/* Look up the first VMA which satisfies addr < vm_end, NULL if none. */ +extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr); +extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr, + struct vm_area_struct **pprev); + +/* + * Look up the first VMA which intersects the interval [start_addr, end_addr) + * NULL if none. Assume start_addr < end_addr. + */ +struct vm_area_struct *find_vma_intersection(struct mm_struct *mm, + unsigned long start_addr, unsigned long end_addr); + +/** + * vma_lookup() - Find a VMA at a specific address + * @mm: The process address space. + * @addr: The user address. + * + * Return: The vm_area_struct at the given address, %NULL otherwise. + */ +static inline +struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr) +{ + return mtree_load(&mm->mm_mt, addr); +} + +static inline unsigned long vm_start_gap(struct vm_area_struct *vma) +{ + unsigned long vm_start = vma->vm_start; + + if (vma->vm_flags & VM_GROWSDOWN) { + vm_start -= stack_guard_gap; + if (vm_start > vma->vm_start) + vm_start = 0; + } + return vm_start; +} + +static inline unsigned long vm_end_gap(struct vm_area_struct *vma) +{ + unsigned long vm_end = vma->vm_end; + + if (vma->vm_flags & VM_GROWSUP) { + vm_end += stack_guard_gap; + if (vm_end < vma->vm_end) + vm_end = -PAGE_SIZE; + } + return vm_end; +} + +static inline unsigned long vma_pages(struct vm_area_struct *vma) +{ + return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; +} + +/* Look up the first VMA which exactly match the interval vm_start ... vm_end */ +static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm, + unsigned long vm_start, unsigned long vm_end) +{ + struct vm_area_struct *vma = vma_lookup(mm, vm_start); + + if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end)) + vma = NULL; + + return vma; +} + +static inline bool range_in_vma(struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + return (vma && vma->vm_start <= start && end <= vma->vm_end); +} + +#ifdef CONFIG_MMU +pgprot_t vm_get_page_prot(unsigned long vm_flags); +void vma_set_page_prot(struct vm_area_struct *vma); +#else +static inline pgprot_t vm_get_page_prot(unsigned long vm_flags) +{ + return __pgprot(0); +} +static inline void vma_set_page_prot(struct vm_area_struct *vma) +{ + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); +} +#endif + +void vma_set_file(struct vm_area_struct *vma, struct file *file); + +#ifdef CONFIG_NUMA_BALANCING +unsigned long change_prot_numa(struct vm_area_struct *vma, + unsigned long start, unsigned long end); +#endif + +struct vm_area_struct *find_extend_vma_locked(struct mm_struct *, + unsigned long addr); +int remap_pfn_range(struct vm_area_struct *, unsigned long addr, + unsigned long pfn, unsigned long size, pgprot_t); +int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn, unsigned long size, pgprot_t prot); +int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *); +int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr, + struct page **pages, unsigned long *num); +int vm_map_pages(struct vm_area_struct *vma, struct page **pages, + unsigned long num); +int vm_map_pages_zero(struct vm_area_struct *vma, struct page **pages, + unsigned long num); +vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn); +vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn, pgprot_t pgprot); +vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr, + pfn_t pfn); +vm_fault_t vmf_insert_mixed_prot(struct vm_area_struct *vma, unsigned long addr, + pfn_t pfn, pgprot_t pgprot); +vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma, + unsigned long addr, pfn_t pfn); +int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len); + +static inline vm_fault_t vmf_insert_page(struct vm_area_struct *vma, + unsigned long addr, struct page *page) +{ + int err = vm_insert_page(vma, addr, page); + + if (err == -ENOMEM) + return VM_FAULT_OOM; + if (err < 0 && err != -EBUSY) + return VM_FAULT_SIGBUS; + + return VM_FAULT_NOPAGE; +} + +#ifndef io_remap_pfn_range +static inline int io_remap_pfn_range(struct vm_area_struct *vma, + unsigned long addr, unsigned long pfn, + unsigned long size, pgprot_t prot) +{ + return remap_pfn_range(vma, addr, pfn, size, pgprot_decrypted(prot)); +} +#endif + +static inline vm_fault_t vmf_error(int err) +{ + if (err == -ENOMEM) + return VM_FAULT_OOM; + return VM_FAULT_SIGBUS; +} + +struct page *follow_page(struct vm_area_struct *vma, unsigned long address, + unsigned int foll_flags); + +#define FOLL_WRITE 0x01 /* check pte is writable */ +#define FOLL_TOUCH 0x02 /* mark page accessed */ +#define FOLL_GET 0x04 /* do get_page on page */ +#define FOLL_DUMP 0x08 /* give error on hole if it would be zero */ +#define FOLL_FORCE 0x10 /* get_user_pages read/write w/o permission */ +#define FOLL_NOWAIT 0x20 /* if a disk transfer is needed, start the IO + * and return without waiting upon it */ +#define FOLL_NOFAULT 0x80 /* do not fault in pages */ +#define FOLL_HWPOISON 0x100 /* check page is hwpoisoned */ +#define FOLL_MIGRATION 0x400 /* wait for page to replace migration entry */ +#define FOLL_TRIED 0x800 /* a retry, previous pass started an IO */ +#define FOLL_REMOTE 0x2000 /* we are working on non-current tsk/mm */ +#define FOLL_ANON 0x8000 /* don't do file mappings */ +#define FOLL_LONGTERM 0x10000 /* mapping lifetime is indefinite: see below */ +#define FOLL_SPLIT_PMD 0x20000 /* split huge pmd before returning */ +#define FOLL_PIN 0x40000 /* pages must be released via unpin_user_page */ +#define FOLL_FAST_ONLY 0x80000 /* gup_fast: prevent fall-back to slow gup */ + +/* + * FOLL_PIN and FOLL_LONGTERM may be used in various combinations with each + * other. Here is what they mean, and how to use them: + * + * FOLL_LONGTERM indicates that the page will be held for an indefinite time + * period _often_ under userspace control. This is in contrast to + * iov_iter_get_pages(), whose usages are transient. + * + * FIXME: For pages which are part of a filesystem, mappings are subject to the + * lifetime enforced by the filesystem and we need guarantees that longterm + * users like RDMA and V4L2 only establish mappings which coordinate usage with + * the filesystem. Ideas for this coordination include revoking the longterm + * pin, delaying writeback, bounce buffer page writeback, etc. As FS DAX was + * added after the problem with filesystems was found FS DAX VMAs are + * specifically failed. Filesystem pages are still subject to bugs and use of + * FOLL_LONGTERM should be avoided on those pages. + * + * FIXME: Also NOTE that FOLL_LONGTERM is not supported in every GUP call. + * Currently only get_user_pages() and get_user_pages_fast() support this flag + * and calls to get_user_pages_[un]locked are specifically not allowed. This + * is due to an incompatibility with the FS DAX check and + * FAULT_FLAG_ALLOW_RETRY. + * + * In the CMA case: long term pins in a CMA region would unnecessarily fragment + * that region. And so, CMA attempts to migrate the page before pinning, when + * FOLL_LONGTERM is specified. + * + * FOLL_PIN indicates that a special kind of tracking (not just page->_refcount, + * but an additional pin counting system) will be invoked. This is intended for + * anything that gets a page reference and then touches page data (for example, + * Direct IO). This lets the filesystem know that some non-file-system entity is + * potentially changing the pages' data. In contrast to FOLL_GET (whose pages + * are released via put_page()), FOLL_PIN pages must be released, ultimately, by + * a call to unpin_user_page(). + * + * FOLL_PIN is similar to FOLL_GET: both of these pin pages. They use different + * and separate refcounting mechanisms, however, and that means that each has + * its own acquire and release mechanisms: + * + * FOLL_GET: get_user_pages*() to acquire, and put_page() to release. + * + * FOLL_PIN: pin_user_pages*() to acquire, and unpin_user_pages to release. + * + * FOLL_PIN and FOLL_GET are mutually exclusive for a given function call. + * (The underlying pages may experience both FOLL_GET-based and FOLL_PIN-based + * calls applied to them, and that's perfectly OK. This is a constraint on the + * callers, not on the pages.) + * + * FOLL_PIN should be set internally by the pin_user_pages*() APIs, never + * directly by the caller. That's in order to help avoid mismatches when + * releasing pages: get_user_pages*() pages must be released via put_page(), + * while pin_user_pages*() pages must be released via unpin_user_page(). + * + * Please see Documentation/core-api/pin_user_pages.rst for more information. + */ + +static inline int vm_fault_to_errno(vm_fault_t vm_fault, int foll_flags) +{ + if (vm_fault & VM_FAULT_OOM) + return -ENOMEM; + if (vm_fault & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE)) + return (foll_flags & FOLL_HWPOISON) ? -EHWPOISON : -EFAULT; + if (vm_fault & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV)) + return -EFAULT; + return 0; +} + +/* + * Indicates for which pages that are write-protected in the page table, + * whether GUP has to trigger unsharing via FAULT_FLAG_UNSHARE such that the + * GUP pin will remain consistent with the pages mapped into the page tables + * of the MM. + * + * Temporary unmapping of PageAnonExclusive() pages or clearing of + * PageAnonExclusive() has to protect against concurrent GUP: + * * Ordinary GUP: Using the PT lock + * * GUP-fast and fork(): mm->write_protect_seq + * * GUP-fast and KSM or temporary unmapping (swap, migration): see + * page_try_share_anon_rmap() + * + * Must be called with the (sub)page that's actually referenced via the + * page table entry, which might not necessarily be the head page for a + * PTE-mapped THP. + */ +static inline bool gup_must_unshare(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)) + return false; + + /* Paired with a memory barrier in page_try_share_anon_rmap(). */ + if (IS_ENABLED(CONFIG_HAVE_FAST_GUP)) + smp_rmb(); + + /* + * During GUP-fast we might not get called on the head page for a + * hugetlb page that is mapped using cont-PTE, because GUP-fast does + * not work with the abstracted hugetlb PTEs that always point at the + * head page. For hugetlb, PageAnonExclusive only applies on the head + * page (as it cannot be partially COW-shared), so lookup the head page. + */ + if (unlikely(!PageHead(page) && PageHuge(page))) + page = compound_head(page); + + /* + * Note that PageKsm() pages cannot be exclusive, and consequently, + * cannot get pinned. + */ + return !PageAnonExclusive(page); +} + +/* + * Indicates whether GUP can follow a PROT_NONE mapped page, or whether + * a (NUMA hinting) fault is required. + */ +static inline bool gup_can_follow_protnone(unsigned int flags) +{ + /* + * FOLL_FORCE has to be able to make progress even if the VMA is + * inaccessible. Further, FOLL_FORCE access usually does not represent + * application behaviour and we should avoid triggering NUMA hinting + * faults. + */ + return flags & FOLL_FORCE; +} + +typedef int (*pte_fn_t)(pte_t *pte, unsigned long addr, void *data); +extern int apply_to_page_range(struct mm_struct *mm, unsigned long address, + unsigned long size, pte_fn_t fn, void *data); +extern int apply_to_existing_page_range(struct mm_struct *mm, + unsigned long address, unsigned long size, + pte_fn_t fn, void *data); + +extern void __init init_mem_debugging_and_hardening(void); +#ifdef CONFIG_PAGE_POISONING +extern void __kernel_poison_pages(struct page *page, int numpages); +extern void __kernel_unpoison_pages(struct page *page, int numpages); +extern bool _page_poisoning_enabled_early; +DECLARE_STATIC_KEY_FALSE(_page_poisoning_enabled); +static inline bool page_poisoning_enabled(void) +{ + return _page_poisoning_enabled_early; +} +/* + * For use in fast paths after init_mem_debugging() has run, or when a + * false negative result is not harmful when called too early. + */ +static inline bool page_poisoning_enabled_static(void) +{ + return static_branch_unlikely(&_page_poisoning_enabled); +} +static inline void kernel_poison_pages(struct page *page, int numpages) +{ + if (page_poisoning_enabled_static()) + __kernel_poison_pages(page, numpages); +} +static inline void kernel_unpoison_pages(struct page *page, int numpages) +{ + if (page_poisoning_enabled_static()) + __kernel_unpoison_pages(page, numpages); +} +#else +static inline bool page_poisoning_enabled(void) { return false; } +static inline bool page_poisoning_enabled_static(void) { return false; } +static inline void __kernel_poison_pages(struct page *page, int nunmpages) { } +static inline void kernel_poison_pages(struct page *page, int numpages) { } +static inline void kernel_unpoison_pages(struct page *page, int numpages) { } +#endif + +DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc); +static inline bool want_init_on_alloc(gfp_t flags) +{ + if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, + &init_on_alloc)) + return true; + return flags & __GFP_ZERO; +} + +DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free); +static inline bool want_init_on_free(void) +{ + return static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON, + &init_on_free); +} + +extern bool _debug_pagealloc_enabled_early; +DECLARE_STATIC_KEY_FALSE(_debug_pagealloc_enabled); + +static inline bool debug_pagealloc_enabled(void) +{ + return IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) && + _debug_pagealloc_enabled_early; +} + +/* + * For use in fast paths after init_debug_pagealloc() has run, or when a + * false negative result is not harmful when called too early. + */ +static inline bool debug_pagealloc_enabled_static(void) +{ + if (!IS_ENABLED(CONFIG_DEBUG_PAGEALLOC)) + return false; + + return static_branch_unlikely(&_debug_pagealloc_enabled); +} + +#ifdef CONFIG_DEBUG_PAGEALLOC +/* + * To support DEBUG_PAGEALLOC architecture must ensure that + * __kernel_map_pages() never fails + */ +extern void __kernel_map_pages(struct page *page, int numpages, int enable); + +static inline void debug_pagealloc_map_pages(struct page *page, int numpages) +{ + if (debug_pagealloc_enabled_static()) + __kernel_map_pages(page, numpages, 1); +} + +static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) +{ + if (debug_pagealloc_enabled_static()) + __kernel_map_pages(page, numpages, 0); +} +#else /* CONFIG_DEBUG_PAGEALLOC */ +static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {} +static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {} +#endif /* CONFIG_DEBUG_PAGEALLOC */ + +#ifdef __HAVE_ARCH_GATE_AREA +extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm); +extern int in_gate_area_no_mm(unsigned long addr); +extern int in_gate_area(struct mm_struct *mm, unsigned long addr); +#else +static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm) +{ + return NULL; +} +static inline int in_gate_area_no_mm(unsigned long addr) { return 0; } +static inline int in_gate_area(struct mm_struct *mm, unsigned long addr) +{ + return 0; +} +#endif /* __HAVE_ARCH_GATE_AREA */ + +extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm); + +#ifdef CONFIG_SYSCTL +extern int sysctl_drop_caches; +int drop_caches_sysctl_handler(struct ctl_table *, int, void *, size_t *, + loff_t *); +#endif + +void drop_slab(void); + +#ifndef CONFIG_MMU +#define randomize_va_space 0 +#else +extern int randomize_va_space; +#endif + +const char * arch_vma_name(struct vm_area_struct *vma); +#ifdef CONFIG_MMU +void print_vma_addr(char *prefix, unsigned long rip); +#else +static inline void print_vma_addr(char *prefix, unsigned long rip) +{ +} +#endif + +void *sparse_buffer_alloc(unsigned long size); +struct page * __populate_section_memmap(unsigned long pfn, + unsigned long nr_pages, int nid, struct vmem_altmap *altmap, + struct dev_pagemap *pgmap); +pgd_t *vmemmap_pgd_populate(unsigned long addr, int node); +p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node); +pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node); +pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node); +pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node, + struct vmem_altmap *altmap, struct page *reuse); +void *vmemmap_alloc_block(unsigned long size, int node); +struct vmem_altmap; +void *vmemmap_alloc_block_buf(unsigned long size, int node, + struct vmem_altmap *altmap); +void vmemmap_verify(pte_t *, int, unsigned long, unsigned long); +int vmemmap_populate_basepages(unsigned long start, unsigned long end, + int node, struct vmem_altmap *altmap); +int vmemmap_populate(unsigned long start, unsigned long end, int node, + struct vmem_altmap *altmap); +void vmemmap_populate_print_last(void); +#ifdef CONFIG_MEMORY_HOTPLUG +void vmemmap_free(unsigned long start, unsigned long end, + struct vmem_altmap *altmap); +#endif +void register_page_bootmem_memmap(unsigned long section_nr, struct page *map, + unsigned long nr_pages); + +enum mf_flags { + MF_COUNT_INCREASED = 1 << 0, + MF_ACTION_REQUIRED = 1 << 1, + MF_MUST_KILL = 1 << 2, + MF_SOFT_OFFLINE = 1 << 3, + MF_UNPOISON = 1 << 4, + MF_SW_SIMULATED = 1 << 5, + MF_NO_RETRY = 1 << 6, +}; +int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, + unsigned long count, int mf_flags); +extern int memory_failure(unsigned long pfn, int flags); +extern void memory_failure_queue_kick(int cpu); +extern int unpoison_memory(unsigned long pfn); +extern int sysctl_memory_failure_early_kill; +extern int sysctl_memory_failure_recovery; +extern void shake_page(struct page *p); +extern atomic_long_t num_poisoned_pages __read_mostly; +extern int soft_offline_page(unsigned long pfn, int flags); +#ifdef CONFIG_MEMORY_FAILURE +extern void memory_failure_queue(unsigned long pfn, int flags); +extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags); +#else +static inline void memory_failure_queue(unsigned long pfn, int flags) +{ +} +static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags) +{ + return 0; +} +#endif + +#ifndef arch_memory_failure +static inline int arch_memory_failure(unsigned long pfn, int flags) +{ + return -ENXIO; +} +#endif + +#ifndef arch_is_platform_page +static inline bool arch_is_platform_page(u64 paddr) +{ + return false; +} +#endif + +/* + * Error handlers for various types of pages. + */ +enum mf_result { + MF_IGNORED, /* Error: cannot be handled */ + MF_FAILED, /* Error: handling failed */ + MF_DELAYED, /* Will be handled later */ + MF_RECOVERED, /* Successfully recovered */ +}; + +enum mf_action_page_type { + MF_MSG_KERNEL, + MF_MSG_KERNEL_HIGH_ORDER, + MF_MSG_SLAB, + MF_MSG_DIFFERENT_COMPOUND, + MF_MSG_HUGE, + MF_MSG_FREE_HUGE, + MF_MSG_UNMAP_FAILED, + MF_MSG_DIRTY_SWAPCACHE, + MF_MSG_CLEAN_SWAPCACHE, + MF_MSG_DIRTY_MLOCKED_LRU, + MF_MSG_CLEAN_MLOCKED_LRU, + MF_MSG_DIRTY_UNEVICTABLE_LRU, + MF_MSG_CLEAN_UNEVICTABLE_LRU, + MF_MSG_DIRTY_LRU, + MF_MSG_CLEAN_LRU, + MF_MSG_TRUNCATED_LRU, + MF_MSG_BUDDY, + MF_MSG_DAX, + MF_MSG_UNSPLIT_THP, + MF_MSG_UNKNOWN, +}; + +#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS) +extern void clear_huge_page(struct page *page, + unsigned long addr_hint, + unsigned int pages_per_huge_page); +extern void copy_user_huge_page(struct page *dst, struct page *src, + unsigned long addr_hint, + struct vm_area_struct *vma, + unsigned int pages_per_huge_page); +extern long copy_huge_page_from_user(struct page *dst_page, + const void __user *usr_src, + unsigned int pages_per_huge_page, + bool allow_pagefault); + +/** + * vma_is_special_huge - Are transhuge page-table entries considered special? + * @vma: Pointer to the struct vm_area_struct to consider + * + * Whether transhuge page-table entries are considered "special" following + * the definition in vm_normal_page(). + * + * Return: true if transhuge page-table entries should be considered special, + * false otherwise. + */ +static inline bool vma_is_special_huge(const struct vm_area_struct *vma) +{ + return vma_is_dax(vma) || (vma->vm_file && + (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP))); +} + +#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */ + +#ifdef CONFIG_DEBUG_PAGEALLOC +extern unsigned int _debug_guardpage_minorder; +DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled); + +static inline unsigned int debug_guardpage_minorder(void) +{ + return _debug_guardpage_minorder; +} + +static inline bool debug_guardpage_enabled(void) +{ + return static_branch_unlikely(&_debug_guardpage_enabled); +} + +static inline bool page_is_guard(struct page *page) +{ + if (!debug_guardpage_enabled()) + return false; + + return PageGuard(page); +} +#else +static inline unsigned int debug_guardpage_minorder(void) { return 0; } +static inline bool debug_guardpage_enabled(void) { return false; } +static inline bool page_is_guard(struct page *page) { return false; } +#endif /* CONFIG_DEBUG_PAGEALLOC */ + +#if MAX_NUMNODES > 1 +void __init setup_nr_node_ids(void); +#else +static inline void setup_nr_node_ids(void) {} +#endif + +extern int memcmp_pages(struct page *page1, struct page *page2); + +static inline int pages_identical(struct page *page1, struct page *page2) +{ + return !memcmp_pages(page1, page2); +} + +#ifdef CONFIG_MAPPING_DIRTY_HELPERS +unsigned long clean_record_shared_mapping_range(struct address_space *mapping, + pgoff_t first_index, pgoff_t nr, + pgoff_t bitmap_pgoff, + unsigned long *bitmap, + pgoff_t *start, + pgoff_t *end); + +unsigned long wp_shared_mapping_range(struct address_space *mapping, + pgoff_t first_index, pgoff_t nr); +#endif + +extern int sysctl_nr_trim_pages; + +#ifdef CONFIG_PRINTK +void mem_dump_obj(void *object); +#else +static inline void mem_dump_obj(void *object) {} +#endif + +/** + * seal_check_future_write - Check for F_SEAL_FUTURE_WRITE flag and handle it + * @seals: the seals to check + * @vma: the vma to operate on + * + * Check whether F_SEAL_FUTURE_WRITE is set; if so, do proper check/handling on + * the vma flags. Return 0 if check pass, or <0 for errors. + */ +static inline int seal_check_future_write(int seals, struct vm_area_struct *vma) +{ + if (seals & F_SEAL_FUTURE_WRITE) { + /* + * New PROT_WRITE and MAP_SHARED mmaps are not allowed when + * "future write" seal active. + */ + if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE)) + return -EPERM; + + /* + * Since an F_SEAL_FUTURE_WRITE sealed memfd can be mapped as + * MAP_SHARED and read-only, take care to not allow mprotect to + * revert protections on such mappings. Do this only for shared + * mappings. For private mappings, don't need to mask + * VM_MAYWRITE as we still want them to be COW-writable. + */ + if (vma->vm_flags & VM_SHARED) + vma->vm_flags &= ~(VM_MAYWRITE); + } + + return 0; +} + +#ifdef CONFIG_ANON_VMA_NAME +int madvise_set_anon_name(struct mm_struct *mm, unsigned long start, + unsigned long len_in, + struct anon_vma_name *anon_name); +#else +static inline int +madvise_set_anon_name(struct mm_struct *mm, unsigned long start, + unsigned long len_in, struct anon_vma_name *anon_name) { + return 0; +} +#endif + +#endif /* _LINUX_MM_H */ |