| /* 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/page_pinner.h> |
| #include <linux/memremap.h> |
| #include <linux/android_kabi.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 *); |
| /* Use only if VMA has no other users */ |
| void __vm_area_free(struct vm_area_struct *vma); |
| |
| #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 represents all the VMA flag bits used by mlock */ |
| #define VM_LOCKED_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" }, \ |
| { FAULT_FLAG_VMA_LOCK, "VMA_LOCK" } |
| |
| /* |
| * 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); |
| |
| ANDROID_KABI_RESERVE(1); |
| ANDROID_KABI_RESERVE(2); |
| ANDROID_KABI_RESERVE(3); |
| ANDROID_KABI_RESERVE(4); |
| }; |
| |
| #ifdef CONFIG_PER_VMA_LOCK |
| /* |
| * Try to read-lock a vma. The function is allowed to occasionally yield false |
| * locked result to avoid performance overhead, in which case we fall back to |
| * using mmap_lock. The function should never yield false unlocked result. |
| */ |
| static inline bool vma_start_read(struct vm_area_struct *vma) |
| { |
| /* |
| * Check before locking. A race might cause false locked result. |
| * We can use READ_ONCE() for the mm_lock_seq here, and don't need |
| * ACQUIRE semantics, because this is just a lockless check whose result |
| * we don't rely on for anything - the mm_lock_seq read against which we |
| * need ordering is below. |
| */ |
| if (READ_ONCE(vma->vm_lock_seq) == READ_ONCE(vma->vm_mm->mm_lock_seq)) |
| return false; |
| |
| if (unlikely(down_read_trylock(&vma->vm_lock->lock) == 0)) |
| return false; |
| |
| /* |
| * Overflow might produce false locked result. |
| * False unlocked result is impossible because we modify and check |
| * vma->vm_lock_seq under vma->vm_lock protection and mm->mm_lock_seq |
| * modification invalidates all existing locks. |
| * |
| * We must use ACQUIRE semantics for the mm_lock_seq so that if we are |
| * racing with vma_end_write_all(), we only start reading from the VMA |
| * after it has been unlocked. |
| * This pairs with RELEASE semantics in vma_end_write_all(). |
| */ |
| if (unlikely(vma->vm_lock_seq == smp_load_acquire(&vma->vm_mm->mm_lock_seq))) { |
| up_read(&vma->vm_lock->lock); |
| return false; |
| } |
| return true; |
| } |
| |
| static inline void vma_end_read(struct vm_area_struct *vma) |
| { |
| rcu_read_lock(); /* keeps vma alive till the end of up_read */ |
| up_read(&vma->vm_lock->lock); |
| rcu_read_unlock(); |
| } |
| |
| /* WARNING! Can only be used if mmap_lock is expected to be write-locked */ |
| static bool __is_vma_write_locked(struct vm_area_struct *vma, int *mm_lock_seq) |
| { |
| mmap_assert_write_locked(vma->vm_mm); |
| |
| /* |
| * current task is holding mmap_write_lock, both vma->vm_lock_seq and |
| * mm->mm_lock_seq can't be concurrently modified. |
| */ |
| *mm_lock_seq = vma->vm_mm->mm_lock_seq; |
| return (vma->vm_lock_seq == *mm_lock_seq); |
| } |
| |
| /* |
| * Begin writing to a VMA. |
| * Exclude concurrent readers under the per-VMA lock until the currently |
| * write-locked mmap_lock is dropped or downgraded. |
| */ |
| static inline void vma_start_write(struct vm_area_struct *vma) |
| { |
| int mm_lock_seq; |
| |
| if (__is_vma_write_locked(vma, &mm_lock_seq)) |
| return; |
| |
| down_write(&vma->vm_lock->lock); |
| /* |
| * We should use WRITE_ONCE() here because we can have concurrent reads |
| * from the early lockless pessimistic check in vma_start_read(). |
| * We don't really care about the correctness of that early check, but |
| * we should use WRITE_ONCE() for cleanliness and to keep KCSAN happy. |
| */ |
| WRITE_ONCE(vma->vm_lock_seq, mm_lock_seq); |
| up_write(&vma->vm_lock->lock); |
| } |
| |
| static inline bool vma_try_start_write(struct vm_area_struct *vma) |
| { |
| int mm_lock_seq; |
| |
| if (__is_vma_write_locked(vma, &mm_lock_seq)) |
| return true; |
| |
| if (!down_write_trylock(&vma->vm_lock->lock)) |
| return false; |
| |
| WRITE_ONCE(vma->vm_lock_seq, mm_lock_seq); |
| up_write(&vma->vm_lock->lock); |
| return true; |
| } |
| |
| static inline void vma_assert_write_locked(struct vm_area_struct *vma) |
| { |
| int mm_lock_seq; |
| |
| VM_BUG_ON_VMA(!__is_vma_write_locked(vma, &mm_lock_seq), vma); |
| } |
| |
| static inline void vma_assert_locked(struct vm_area_struct *vma) |
| { |
| if (!rwsem_is_locked(&vma->vm_lock->lock)) |
| vma_assert_write_locked(vma); |
| } |
| |
| static inline void vma_mark_detached(struct vm_area_struct *vma, bool detached) |
| { |
| /* When detaching vma should be write-locked */ |
| if (detached) |
| vma_assert_write_locked(vma); |
| vma->detached = detached; |
| } |
| |
| static inline void release_fault_lock(struct vm_fault *vmf) |
| { |
| if (vmf->flags & FAULT_FLAG_VMA_LOCK) |
| vma_end_read(vmf->vma); |
| else |
| mmap_read_unlock(vmf->vma->vm_mm); |
| } |
| |
| static inline void assert_fault_locked(struct vm_fault *vmf) |
| { |
| if (vmf->flags & FAULT_FLAG_VMA_LOCK) |
| vma_assert_locked(vmf->vma); |
| else |
| mmap_assert_locked(vmf->vma->vm_mm); |
| } |
| |
| struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, |
| unsigned long address); |
| |
| #else /* CONFIG_PER_VMA_LOCK */ |
| |
| static inline void vma_init_lock(struct vm_area_struct *vma) {} |
| static inline bool vma_start_read(struct vm_area_struct *vma) |
| { return false; } |
| static inline void vma_end_read(struct vm_area_struct *vma) {} |
| static inline void vma_start_write(struct vm_area_struct *vma) {} |
| static inline bool vma_try_start_write(struct vm_area_struct *vma) |
| { return true; } |
| static inline void vma_assert_write_locked(struct vm_area_struct *vma) |
| { mmap_assert_write_locked(vma->vm_mm); } |
| static inline void vma_mark_detached(struct vm_area_struct *vma, |
| bool detached) {} |
| |
| static inline void vma_assert_locked(struct vm_area_struct *vma) |
| { |
| mmap_assert_locked(vma->vm_mm); |
| } |
| |
| static inline void release_fault_lock(struct vm_fault *vmf) |
| { |
| mmap_read_unlock(vmf->vma->vm_mm); |
| } |
| |
| static inline void assert_fault_locked(struct vm_fault *vmf) |
| { |
| mmap_assert_locked(vmf->vma->vm_mm); |
| } |
| |
| static inline struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, |
| unsigned long address) |
| { |
| return NULL; |
| } |
| |
| #endif /* CONFIG_PER_VMA_LOCK */ |
| |
| /* |
| * WARNING: vma_init does not initialize vma->vm_lock. |
| * Use vm_area_alloc()/vm_area_free() if vma needs locking. |
| */ |
| 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); |
| vma_mark_detached(vma, false); |
| } |
| |
| /* Use when VMA is not part of the VMA tree and needs no locking */ |
| static inline void vm_flags_init(struct vm_area_struct *vma, |
| vm_flags_t flags) |
| { |
| ACCESS_PRIVATE(vma, __vm_flags) = flags; |
| } |
| |
| /* |
| * Use when VMA is part of the VMA tree and modifications need coordination |
| * Note: vm_flags_reset and vm_flags_reset_once do not lock the vma and |
| * it should be locked explicitly beforehand. |
| */ |
| static inline void vm_flags_reset(struct vm_area_struct *vma, |
| vm_flags_t flags) |
| { |
| vma_assert_write_locked(vma); |
| vm_flags_init(vma, flags); |
| } |
| |
| static inline void vm_flags_reset_once(struct vm_area_struct *vma, |
| vm_flags_t flags) |
| { |
| vma_assert_write_locked(vma); |
| WRITE_ONCE(ACCESS_PRIVATE(vma, __vm_flags), flags); |
| } |
| |
| static inline void vm_flags_set(struct vm_area_struct *vma, |
| vm_flags_t flags) |
| { |
| vma_start_write(vma); |
| ACCESS_PRIVATE(vma, __vm_flags) |= flags; |
| } |
| |
| static inline void vm_flags_clear(struct vm_area_struct *vma, |
| vm_flags_t flags) |
| { |
| vma_start_write(vma); |
| ACCESS_PRIVATE(vma, __vm_flags) &= ~flags; |
| } |
| |
| /* |
| * Use only if VMA is not part of the VMA tree or has no other users and |
| * therefore needs no locking. |
| */ |
| static inline void __vm_flags_mod(struct vm_area_struct *vma, |
| vm_flags_t set, vm_flags_t clear) |
| { |
| vm_flags_init(vma, (vma->vm_flags | set) & ~clear); |
| } |
| |
| /* |
| * Use only when the order of set/clear operations is unimportant, otherwise |
| * use vm_flags_{set|clear} explicitly. |
| */ |
| static inline void vm_flags_mod(struct vm_area_struct *vma, |
| vm_flags_t set, vm_flags_t clear) |
| { |
| vma_start_write(vma); |
| __vm_flags_mod(vma, set, clear); |
| } |
| |
| 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) |
| { |
| int ret; |
| |
| VM_BUG_ON_PAGE(page_ref_count(page) == 0, page); |
| ret = page_ref_dec_and_test(page); |
| page_pinner_put_page(page); |
| |
| return ret; |
| } |
| |
| 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, unsigned long start_t, |
| unsigned long end_t, bool mm_wr_locked); |
| |
| 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); |
| |
| #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); |
| struct vm_area_struct *lock_mm_and_find_vma(struct mm_struct *mm, |
| unsigned long address, struct pt_regs *regs); |
| #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) |
| { |
|