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android-kvm / linux / 51ceeb1a8142537b9f65aeaac6c301560a948197 / . / include / linux / mm.h
blob: ecf63d2b058255e1855fd35d7838674443b516f9 [file] [log] [blame]
/* 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/pgalloc_tag.h>
#include <linux/bug.h>
#include <linux/list.h>
#include <linux/mmzone.h>
#include <linux/rbtree.h>
#include <linux/atomic.h>
#include <linux/debug_locks.h>
#include <linux/mm_types.h>
#include <linux/mmap_lock.h>
#include <linux/range.h>
#include <linux/pfn.h>
#include <linux/percpu-refcount.h>
#include <linux/bit_spinlock.h>
#include <linux/shrinker.h>
#include <linux/resource.h>
#include <linux/page_ext.h>
#include <linux/err.h>
#include <linux/page-flags.h>
#include <linux/page_ref.h>
#include <linux/overflow.h>
#include <linux/sizes.h>
#include <linux/sched.h>
#include <linux/pgtable.h>
#include <linux/kasan.h>
#include <linux/memremap.h>
#include <linux/slab.h>
struct mempolicy;
struct anon_vma;
struct anon_vma_chain;
struct user_struct;
struct pt_regs;
struct folio_batch;
extern int sysctl_page_lock_unfairness;
void mm_core_init(void);
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;
extern const int page_cluster_max;
#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 int mmap_rnd_bits_max __ro_after_init;
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
#ifndef PHYSMEM_END
# ifdef MAX_PHYSMEM_BITS
# define PHYSMEM_END ((1ULL << MAX_PHYSMEM_BITS) - 1)
# else
# define PHYSMEM_END (((phys_addr_t)-1)&~(1ULL<<63))
# endif
#endif
#include <asm/page.h>
#include <asm/processor.h>
#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(const struct ctl_table *, int, void *, size_t *,
loff_t *);
int overcommit_kbytes_handler(const struct ctl_table *, int, void *, size_t *,
loff_t *);
int overcommit_policy_handler(const 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)
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 */
#ifdef CONFIG_MMU
#define VM_UFFD_MISSING 0x00000200 /* missing pages tracking */
#else /* CONFIG_MMU */
#define VM_MAYOVERLAY 0x00000200 /* nommu: R/O MAP_PRIVATE mapping that might overlay a file mapping */
#define VM_UFFD_MISSING 0
#endif /* CONFIG_MMU */
#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_BIT_5 37 /* 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)
#define VM_HIGH_ARCH_5 BIT(VM_HIGH_ARCH_BIT_5)
#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
# define VM_PKEY_BIT1 VM_HIGH_ARCH_1
# define VM_PKEY_BIT2 VM_HIGH_ARCH_2
#if CONFIG_ARCH_PKEY_BITS > 3
# define VM_PKEY_BIT3 VM_HIGH_ARCH_3
#else
# define VM_PKEY_BIT3 0
#endif
#if CONFIG_ARCH_PKEY_BITS > 4
# define VM_PKEY_BIT4 VM_HIGH_ARCH_4
#else
# define VM_PKEY_BIT4 0
#endif
#endif /* CONFIG_ARCH_HAS_PKEYS */
#ifdef CONFIG_X86_USER_SHADOW_STACK
/*
* VM_SHADOW_STACK should not be set with VM_SHARED because of lack of
* support core mm.
*
* These VMAs will get a single end guard page. This helps userspace protect
* itself from attacks. A single page is enough for current shadow stack archs
* (x86). See the comments near alloc_shstk() in arch/x86/kernel/shstk.c
* for more details on the guard size.
*/
# define VM_SHADOW_STACK VM_HIGH_ARCH_5
#else
# define VM_SHADOW_STACK VM_NONE
#endif
#if defined(CONFIG_X86)
# define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */
#elif defined(CONFIG_PPC64)
# define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */
#elif defined(CONFIG_PARISC)
# 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_4 /* Use Tagged memory for access control */
# define VM_MTE_ALLOWED VM_HIGH_ARCH_5 /* 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 38
# 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 */
/*
* This flag is used to connect VFIO to arch specific KVM code. It
* indicates that the memory under this VMA is safe for use with any
* non-cachable memory type inside KVM. Some VFIO devices, on some
* platforms, are thought to be unsafe and can cause machine crashes
* if KVM does not lock down the memory type.
*/
#ifdef CONFIG_64BIT
#define VM_ALLOW_ANY_UNCACHED_BIT 39
#define VM_ALLOW_ANY_UNCACHED BIT(VM_ALLOW_ANY_UNCACHED_BIT)
#else
#define VM_ALLOW_ANY_UNCACHED VM_NONE
#endif
#ifdef CONFIG_64BIT
#define VM_DROPPABLE_BIT 40
#define VM_DROPPABLE BIT(VM_DROPPABLE_BIT)
#elif defined(CONFIG_PPC32)
#define VM_DROPPABLE VM_ARCH_1
#else
#define VM_DROPPABLE VM_NONE
#endif
#ifdef CONFIG_64BIT
/* VM is sealed, in vm_flags */
#define VM_SEALED _BITUL(63)
#endif
/* 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
#define VM_STARTGAP_FLAGS (VM_GROWSDOWN | VM_SHADOW_STACK)
#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.
*/
};
/*
* 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 mprotect() 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, unsigned int order);
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, pgoff_t *ilx);
#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);
};
#ifdef CONFIG_NUMA_BALANCING
static inline void vma_numab_state_init(struct vm_area_struct *vma)
{
vma->numab_state = NULL;
}
static inline void vma_numab_state_free(struct vm_area_struct *vma)
{
kfree(vma->numab_state);
}
#else
static inline void vma_numab_state_init(struct vm_area_struct *vma) {}
static inline void vma_numab_state_free(struct vm_area_struct *vma) {}
#endif /* CONFIG_NUMA_BALANCING */
#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 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 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 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 struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm,
unsigned long address)
{
return NULL;
}
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);
}
#endif /* CONFIG_PER_VMA_LOCK */
extern const struct vm_operations_struct vma_dummy_vm_ops;
/*
* 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)
{
memset(vma, 0, sizeof(*vma));
vma->vm_mm = mm;
vma->vm_ops = &vma_dummy_vm_ops;
INIT_LIST_HEAD(&vma->anon_vma_chain);
vma_mark_detached(vma, false);
vma_numab_state_init(vma);
}
/* 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;
}
/*
* Indicate if the VMA is a heap for the given task; for
* /proc/PID/maps that is the heap of the main task.
*/
static inline bool vma_is_initial_heap(const struct vm_area_struct *vma)
{
return vma->vm_start < vma->vm_mm->brk &&
vma->vm_end > vma->vm_mm->start_brk;
}
/*
* Indicate if the VMA is a stack for the given task; for
* /proc/PID/maps that is the stack of the main task.
*/
static inline bool vma_is_initial_stack(const struct vm_area_struct *vma)
{
/*
* We make no effort to guess what a given thread considers to be
* its "stack". It's not even well-defined for programs written
* languages like Go.
*/
return vma->vm_start <= vma->vm_mm->start_stack &&
vma->vm_end >= vma->vm_mm->start_stack;
}
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 bool is_shared_maywrite(vm_flags_t vm_flags)
{
return (vm_flags & (VM_SHARED | VM_MAYWRITE)) ==
(VM_SHARED | VM_MAYWRITE);
}
static inline bool vma_is_shared_maywrite(struct vm_area_struct *vma)
{
return is_shared_maywrite(vma->vm_flags);
}
static inline
struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max)
{
return mas_find(&vmi->mas, max - 1);
}
static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi)
{
/*
* Uses mas_find() to get the first VMA when the iterator starts.
* Calling mas_next() could skip the first entry.
*/
return mas_find(&vmi->mas, ULONG_MAX);
}
static inline
struct vm_area_struct *vma_iter_next_range(struct vma_iterator *vmi)
{
return mas_next_range(&vmi->mas, ULONG_MAX);
}
static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi)
{
return mas_prev(&vmi->mas, 0);
}
static inline int vma_iter_clear_gfp(struct vma_iterator *vmi,
unsigned long start, unsigned long end, gfp_t gfp)
{
__mas_set_range(&vmi->mas, start, end - 1);
mas_store_gfp(&vmi->mas, NULL, gfp);
if (unlikely(mas_is_err(&vmi->mas)))
return -ENOMEM;
return 0;
}
/* Free any unused preallocations */
static inline void vma_iter_free(struct vma_iterator *vmi)
{
mas_destroy(&vmi->mas);
}
static inline int vma_iter_bulk_store(struct vma_iterator *vmi,
struct vm_area_struct *vma)
{
vmi->mas.index = vma->vm_start;
vmi->mas.last = vma->vm_end - 1;
mas_store(&vmi->mas, vma);
if (unlikely(mas_is_err(&vmi->mas)))
return -ENOMEM;
return 0;
}
static inline void vma_iter_invalidate(struct vma_iterator *vmi)
{
mas_pause(&vmi->mas);
}
static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr)
{
mas_set(&vmi->mas, addr);
}
#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))) != 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);
bool vma_is_anon_shmem(struct vm_area_struct *vma);
#else
static inline bool vma_is_shmem(struct vm_area_struct *vma) { return false; }
static inline bool vma_is_anon_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;
/*
* compound_order() can be called without holding a reference, which means
* that niceties like page_folio() don't work. These callers should be
* prepared to handle wild return values. For example, PG_head may be
* set before the order is initialised, or this may be a tail page.
* See compaction.c for some good examples.
*/
static inline unsigned int compound_order(struct page *page)
{
struct folio *folio = (struct folio *)page;
if (!test_bit(PG_head, &folio->flags))
return 0;
return folio->_flags_1 & 0xff;
}
/**
* 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(const struct folio *folio)
{
if (!folio_test_large(folio))
return 0;
return folio->_flags_1 & 0xff;
}
#include <linux/huge_mm.h>
/*
* Methods to modify the page usage count.
*
* What counts for a page usage:
* - cache mapping (page->mapping)
* - private data (page->private)
* - page mapped in a task's page tables, each mapping
* is counted separately
*
* Also, many kernel routines increase the page count before a critical
* routine so they can be sure the page doesn't go away from under them.
*/
/*
* Drop a ref, return true if the refcount fell to zero (the page has no users)
*/
static inline int put_page_testzero(struct page *page)
{
VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
return page_ref_dec_and_test(page);
}
static inline int folio_put_testzero(struct folio *folio)
{
return put_page_testzero(&folio->page);
}
/*
* Try to grab a ref unless the page has a refcount of zero, return false if
* that is the case.
* This can be called when MMU is off so it must not access
* any of the virtual mappings.
*/
static inline bool get_page_unless_zero(struct page *page)
{
return page_ref_add_unless(page, 1, 0);
}
static inline struct folio *folio_get_nontail_page(struct page *page)
{
if (unlikely(!get_page_unless_zero(page)))
return NULL;
return (struct folio *)page;
}
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.
*/
#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 or implementation of other core folio_*() primitives.
*/
static inline int folio_entire_mapcount(const struct folio *folio)
{
VM_BUG_ON_FOLIO(!folio_test_large(folio), folio);
return atomic_read(&folio->_entire_mapcount) + 1;
}
static inline int folio_large_mapcount(const struct folio *folio)
{
VM_WARN_ON_FOLIO(!folio_test_large(folio), folio);
return atomic_read(&folio->_large_mapcount) + 1;
}
/**
* folio_mapcount() - Number of mappings of this folio.
* @folio: The folio.
*
* The folio mapcount corresponds to the number of present user page table
* entries that reference any part of a folio. Each such present user page
* table entry must be paired with exactly on folio reference.
*
* For ordindary folios, each user page table entry (PTE/PMD/PUD/...) counts
* exactly once.
*
* For hugetlb folios, each abstracted "hugetlb" user page table entry that
* references the entire folio counts exactly once, even when such special
* page table entries are comprised of multiple ordinary page table entries.
*
* Will report 0 for pages which cannot be mapped into userspace, such as
* slab, page tables and similar.
*
* Return: The number of times this folio is mapped.
*/
static inline int folio_mapcount(const struct folio *folio)
{
int mapcount;
if (likely(!folio_test_large(folio))) {
mapcount = atomic_read(&folio->_mapcount) + 1;
if (page_mapcount_is_type(mapcount))
mapcount = 0;
return mapcount;
}
return folio_large_mapcount(folio);
}
/**
* folio_mapped - Is this folio mapped into userspace?
* @folio: The folio.
*
* Return: True if any page in this folio is referenced by user page tables.
*/
static inline bool folio_mapped(const struct folio *folio)
{
return folio_mapcount(folio) >= 1;
}
/*
* Return true if this page is mapped into pagetables.
* For compound page it returns true if any sub-page of compound page is mapped,
* even if this particular sub-page is not itself mapped by any PTE or PMD.
*/
static inline bool page_mapped(const struct page *page)
{
return folio_mapped(page_folio(page));
}
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);
int folio_mc_copy(struct folio *dst, struct folio *src);
unsigned long nr_free_buffer_pages(void);
/* 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_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);
}
#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, vma);
return pte;
}
vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page);
void set_pte_range(struct vm_fault *vmf, struct folio *folio,
struct page *page, unsigned int nr, unsigned long addr);
vm_fault_t finish_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_folio_refs(struct folio *folio, int refs);
static inline bool put_devmap_managed_folio_refs(struct folio *folio, int refs)
{
if (!static_branch_unlikely(&devmap_managed_key))
return false;
if (!folio_is_zone_device(folio))
return false;
return __put_devmap_managed_folio_refs(folio, refs);
}
#else /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
static inline bool put_devmap_managed_folio_refs(struct folio *folio, int refs)
{
return false;
}
#endif /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
/* 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));
}
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 folios_put_refs(struct folio_batch *folios, unsigned int *refs);
/*
* union release_pages_arg - an array of pages or folios
*
* release_pages() releases a simple array of multiple pages, and
* accepts various different forms of said page array: either
* a regular old boring array of pages, an array of folios, or
* an array of encoded page pointers.
*
* The transparent union syntax for this kind of "any of these
* argument types" is all kinds of ugly, so look away.
*/
typedef union {
struct page **pages;
struct folio **folios;
struct encoded_page **encoded_pages;
} release_pages_arg __attribute__ ((__transparent_union__));
void release_pages(release_pages_arg, int nr);
/**
* folios_put - Decrement the reference count on an array of folios.
* @folios: The folios.
*
* Like folio_put(), but for a batch 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. The folios batch is returned
* empty and ready to be reused for another batch; there is no need to
* reinitialise it.
*
* 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_batch *folios)
{
folios_put_refs(folios, NULL);
}
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_folio_refs(folio, 1))
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(), folio_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_folio(struct folio *folio);
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);
void unpin_user_folio(struct folio *folio, unsigned long npages);
void unpin_folios(struct folio **folios, unsigned long nfolios);
static inline bool is_cow_mapping(vm_flags_t flags)
{
return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
}
#ifndef CONFIG_MMU
static inline bool is_nommu_shared_mapping(vm_flags_t flags)
{
/*
* NOMMU shared mappings are ordinary MAP_SHARED mappings and selected
* R/O MAP_PRIVATE file mappings that are an effective R/O overlay of
* a file mapping. R/O MAP_PRIVATE mappings might still modify
* underlying memory if ptrace is active, so this is only possible if
* ptrace does not apply. Note that there is no mprotect() to upgrade
* write permissions later.
*/
return flags & (VM_MAYSHARE | VM_MAYOVERLAY);
}
#endif
#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
int page_to_nid(const struct page *page);
#else
static inline int page_to_nid(const struct page *page)
{
return (PF_POISONED_CHECK(page)->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 folio_xchg_last_cpupid(struct folio *folio, int cpupid)
{
return xchg(&folio->_last_cpupid, cpupid & LAST_CPUPID_MASK);
}
static inline int folio_last_cpupid(struct folio *folio)
{
return folio->_last_cpupid;
}
static inline void page_cpupid_reset_last(struct page *page)
{
page->_last_cpupid = -1 & LAST_CPUPID_MASK;
}
#else
static inline int folio_last_cpupid(struct folio *folio)
{
return (folio->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
}
int folio_xchg_last_cpupid(struct folio *folio, 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 folio_xchg_access_time(struct folio *folio, int time)
{
int last_time;
last_time = folio_xchg_last_cpupid(folio,
time >> PAGE_ACCESS_TIME_BUCKETS);
return last_time << PAGE_ACCESS_TIME_BUCKETS;
}
static inline void vma_set_access_pid_bit(struct vm_area_struct *vma)
{
unsigned int pid_bit;
pid_bit = hash_32(current->pid, ilog2(BITS_PER_LONG));
if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->pids_active[1])) {
__set_bit(pid_bit, &vma->numab_state->pids_active[1]);
}
}
bool folio_use_access_time(struct folio *folio);
#else /* !CONFIG_NUMA_BALANCING */
static inline int folio_xchg_last_cpupid(struct folio *folio, int cpupid)
{
return folio_nid(folio); /* XXX */
}
static inline int folio_xchg_access_time(struct folio *folio, int time)
{
return 0;
}
static inline int folio_last_cpupid(struct folio *folio)
{
return folio_nid(folio); /* 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;
}
static inline void vma_set_access_pid_bit(struct vm_area_struct *vma)
{
}
static inline bool folio_use_access_time(struct folio *folio)
{
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 = KASAN_TAG_KERNEL;
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, KASAN_TAG_KERNEL);
}
#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));
}
/**
* 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 _pincount field 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 folio has been "dma-pinned".
* False, if the folio 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) > 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;
}
/*
* 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 folio_needs_cow_for_dma(struct vm_area_struct *vma,
struct folio *folio)
{
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 folio_maybe_dma_pinned(folio);
}
/**
* is_zero_page - Query if a page is a zero page
* @page: The page to query
*
* This returns true if @page is one of the permanent zero pages.
*/
static inline bool is_zero_page(const struct page *page)
{
return is_zero_pfn(page_to_pfn(page));
}
/**
* is_zero_folio - Query if a folio is a zero page
* @folio: The folio to query
*
* This returns true if @folio is one of the permanent zero pages.
*/
static inline bool is_zero_folio(const struct folio *folio)
{
return is_zero_page(&folio->page);
}
/* MIGRATE_CMA and ZONE_MOVABLE do not allow pin folios */
#ifdef CONFIG_MIGRATION
static inline bool folio_is_longterm_pinnable(struct folio *folio)
{
#ifdef CONFIG_CMA
int mt = folio_migratetype(folio);
if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE)
return false;
#endif
/* The zero page can be "pinned" but gets special handling. */
if (is_zero_folio(folio))
return true;
/* Coherent device memory must always allow eviction. */
if (folio_is_device_coherent(folio))
return false;
/* Otherwise, non-movable zone folios can be pinned. */
return !folio_is_zone_movable(folio);
}
#else
static inline bool folio_is_longterm_pinnable(struct folio *folio)
{
return true;
}
#endif
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(const struct folio *folio)
{
if (!folio_test_large(folio))
return 1;
#ifdef CONFIG_64BIT
return folio->_folio_nr_pages;
#else
return 1L << (folio->_flags_1 & 0xff);
#endif
}
/* Only hugetlbfs can allocate folios larger than MAX_ORDER */
#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
#define MAX_FOLIO_NR_PAGES (1UL << PUD_ORDER)
#else
#define MAX_FOLIO_NR_PAGES MAX_ORDER_NR_PAGES
#endif
/*
* compound_nr() returns the number of pages in this potentially compound
* page. compound_nr() can be called on a tail page, and is defined to
* return 1 in that case.
*/
static inline unsigned long compound_nr(struct page *page)
{
struct folio *folio = (struct folio *)page;
if (!test_bit(PG_head, &folio->flags))
return 1;
#ifdef CONFIG_64BIT
return folio->_folio_nr_pages;
#else
return 1L << (folio->_flags_1 & 0xff);
#endif
}
/**
* 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)
{
return folio_nr_pages((struct folio *)page);
}
/**
* 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(const 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(const struct folio *folio)
{
return PAGE_SIZE << folio_order(folio);
}
/**
* folio_likely_mapped_shared - Estimate if the folio is mapped into the page
* tables of more than one MM
* @folio: The folio.
*
* This function checks if the folio is currently mapped into more than one
* MM ("mapped shared"), or if the folio is only mapped into a single MM
* ("mapped exclusively").
*
* For KSM folios, this function also returns "mapped shared" when a folio is
* mapped multiple times into the same MM, because the individual page mappings
* are independent.
*
* As precise information is not easily available for all folios, this function
* estimates the number of MMs ("sharers") that are currently mapping a folio
* using the number of times the first page of the folio is currently mapped
* into page tables.
*
* For small anonymous folios and anonymous hugetlb folios, the return
* value will be exactly correct: non-KSM folios can only be mapped at most once
* into an MM, and they cannot be partially mapped. KSM folios are
* considered shared even if mapped multiple times into the same MM.
*
* For other folios, the result can be fuzzy:
* #. For partially-mappable large folios (THP), the return value can wrongly
* indicate "mapped exclusively" (false negative) when the folio is
* only partially mapped into at least one MM.
* #. For pagecache folios (including hugetlb), the return value can wrongly
* indicate "mapped shared" (false positive) when two VMAs in the same MM
* cover the same file range.
*
* Further, this function only considers current page table mappings that
* are tracked using the folio mapcount(s).
*
* This function does not consider:
* #. If the folio might get mapped in the (near) future (e.g., swapcache,
* pagecache, temporary unmapping for migration).
* #. If the folio is mapped differently (VM_PFNMAP).
* #. If hugetlb page table sharing applies. Callers might want to check
* hugetlb_pmd_shared().
*
* Return: Whether the folio is estimated to be mapped into more than one MM.
*/
static inline bool folio_likely_mapped_shared(struct folio *folio)
{
int mapcount = folio_mapcount(folio);
/* Only partially-mappable folios require more care. */
if (!folio_test_large(folio) || unlikely(folio_test_hugetlb(folio)))
return mapcount > 1;
/* A single mapping implies "mapped exclusively". */
if (mapcount <= 1)
return false;
/* If any page is mapped more than once we treat it "mapped shared". */
if (folio_entire_mapcount(folio) || mapcount > folio_nr_pages(folio))
return true;
/* Let's guess based on the first subpage. */
return atomic_read(&folio->_mapcount) > 0;
}
#ifndef HAVE_ARCH_MAKE_FOLIO_ACCESSIBLE
static inline int arch_make_folio_accessible(struct folio *folio)
{
return 0;
}
#endif
/*
* Some inline functions in vmstat.h depend on page_zone()
*/
#include <linux/vmstat.h>
#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
static __always_inline void *lowmem_page_address(const struct page *page)
{
return page_to_virt(page);
}
#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);
}
/*
* 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);
}
/*
* Return true only if the folio 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 folio_is_pfmemalloc(const struct folio *folio)
{
/*
* 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)folio->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))
/*
* 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_SCHED_MM_CID
void sched_mm_cid_before_execve(struct task_struct *t);
void sched_mm_cid_after_execve(struct task_struct *t);
void sched_mm_cid_fork(struct task_struct *t);
void sched_mm_cid_exit_signals(struct task_struct *t);
static inline int task_mm_cid(struct task_struct *t)
{
return t->mm_cid;
}
#else
static inline void sched_mm_cid_before_execve(struct task_struct *t) { }
static inline void sched_mm_cid_after_execve(struct task_struct *t) { }
static inline void sched_mm_cid_fork(struct task_struct *t) { }
static inline void sched_mm_cid_exit_signals(struct task_struct *t) { }
static inline int task_mm_cid(struct task_struct *t)
{
/*
* Use the processor id as a fall-back when the mm cid feature is
* disabled. This provides functional per-cpu data structure accesses
* in user-space, althrough it won't provide the memory usage benefits.
*/
return raw_smp_processor_id();
}
#endif
#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 folio *vm_normal_folio_pmd(struct vm_area_struct *vma,
unsigned long addr, pmd_t pmd);
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_single(struct vm_area_struct *vma, unsigned long address,
unsigned long size, struct zap_details *details);
static inline void zap_vma_pages(struct vm_area_struct *vma)
{
zap_page_range_single(vma, vma->vm_start,
vma->vm_end - vma->vm_start, NULL);
}
void unmap_vmas(struct mmu_gather *tlb, struct ma_state *mas,
struct vm_area_struct *start_vma, unsigned long start,
unsigned long end, unsigned long tree_end, 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 generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
void *buf, int len, int write);
struct follow_pfnmap_args {
/**
* Inputs:
* @vma: Pointer to @vm_area_struct struct
* @address: the virtual address to walk
*/
struct vm_area_struct *vma;
unsigned long address;
/**
* Internals:
*
* The caller shouldn't touch any of these.
*/
spinlock_t *lock;
pte_t *ptep;
/**
* Outputs:
*
* @pfn: the PFN of the address
* @pgprot: the pgprot_t of the mapping
* @writable: whether the mapping is writable
* @special: whether the mapping is a special mapping (real PFN maps)
*/
unsigned long pfn;
pgprot_t pgprot;
bool writable;
bool special;
};
int follow_pfnmap_start(struct follow_pfnmap_args *args);
void follow_pfnmap_end(struct follow_pfnmap_args *args);
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_folio(struct address_space *mapping,
struct folio *folio);
struct vm_area_struct *lock_mm_and_find_vma(struct mm_struct *mm,
unsigned long address, struct pt_regs *regs);
#ifdef CONFIG_MMU
extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
unsigned long address, unsigned int flags,
struct pt_regs *regs);
extern int fixup_user_fault(struct mm_struct *mm,
unsigned long address, unsigned int fault_flags,
bool *unlocked);
void unmap_mapping_pages(struct address_space *mapping,
pgoff_t start, pgoff_t nr, bool even_cows);
void unmap_mapping_range(struct address_space *mapping,
loff_t const holebegin, loff_t const holelen, int even_cows);
#else
static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
unsigned long address, unsigned int flags,
struct pt_regs *regs)
{
/* should never happen if there's no MMU */
BUG();
return VM_FAULT_SIGBUS;
}
static inline int fixup_user_fault(struct mm_struct *mm, unsigned long address,
unsigned int fault_flags, bool *unlocked)
{
/* should never happen if there's no MMU */
BUG();
return -EFAULT;
}
static inline void unmap_mapping_pages(struct address_space *mapping,
pgoff_t start, pgoff_t nr, bool even_cows) { }
static inline void unmap_mapping_range(struct address_space *mapping,
loff_t const holebegin, loff_t const holelen, int even_cows) { }
#endif
static inline void unmap_shared_mapping_range(struct address_space *mapping,
loff_t const holebegin, loff_t const holelen)
{
unmap_mapping_range(mapping, holebegin, holelen, 0);
}
static inline struct vm_area_struct *vma_lookup(struct mm_struct *mm,
unsigned long addr);
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);
long get_user_pages_remote(struct mm_struct *mm,
unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages,
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,
int *locked);
/*
* Retrieves a single page alongside its VMA. Does not support FOLL_NOWAIT.
*/
static inline struct page *get_user_page_vma_remote(struct mm_struct *mm,
unsigned long addr,
int gup_flags,
struct vm_area_struct **vmap)
{
struct page *page;
struct vm_area_struct *vma;
int got;
if (WARN_ON_ONCE(unlikely(gup_flags & FOLL_NOWAIT)))
return ERR_PTR(-EINVAL);
got = get_user_pages_remote(mm, addr, 1, gup_flags, &page, NULL);
if (got < 0)
return ERR_PTR(got);
vma = vma_lookup(mm, addr);
if (WARN_ON_ONCE(!vma)) {
put_page(page);
return ERR_PTR(-EINVAL);
}
*vmap = vma;
return page;
}
long get_user_pages(unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages);
long pin_user_pages(unsigned long start, unsigned long nr_pages,
unsigned int gup_flags, struct page **pages);
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);
long memfd_pin_folios(struct file *memfd, loff_t start, loff_t end,
struct folio **folios, unsigned int max_folios,
pgoff_t *offset);
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);
void folio_add_pin(struct folio *folio);
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;
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);
/*
* 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)
bool can_change_pte_writable(struct vm_area_struct *vma, unsigned long addr,
pte_t pte);
extern long change_protection(struct mmu_gather *tlb,
struct vm_area_struct *vma, unsigned long start,
unsigned long end, unsigned long cp_flags);
extern int mprotect_fixup(struct vma_iterator *vmi, 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);
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)
{
return percpu_counter_read_positive(&mm->rss_stat[member]);
}
void mm_trace_rss_stat(struct mm_struct *mm, int member);
static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
{
percpu_counter_add(&mm->rss_stat[member], value);
mm_trace_rss_stat(mm, member);
}
static inline void inc_mm_counter(struct mm_struct *mm, int member)
{
percpu_counter_inc(&mm->rss_stat[member]);
mm_trace_rss_stat(mm, member);
}
static inline void dec_mm_counter(struct mm_struct *mm, int member)
{
percpu_counter_dec(&mm->rss_stat[member]);
mm_trace_rss_stat(mm, member);
}
/* Optimized variant when folio is already known not to be anon */
static inline int mm_counter_file(struct folio *folio)
{
if (folio_test_swapbacked(folio))
return MM_SHMEMPAGES;
return MM_FILEPAGES;
}
static inline int mm_counter(struct folio *folio)
{
if (folio_test_anon(folio))
return MM_ANONPAGES;
return mm_counter_file(folio);
}
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;
}
#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_SUPPORTS_PMD_PFNMAP
static inline bool pmd_special(pmd_t pmd)
{
return false;
}
static inline pmd_t pmd_mkspecial(pmd_t pmd)
{
return pmd;
}
#endif /* CONFIG_ARCH_SUPPORTS_PMD_PFNMAP */
#ifndef CONFIG_ARCH_SUPPORTS_PUD_PFNMAP
static inline bool pud_special(pud_t pud)
{
return false;
}
static inline pud_t pud_mkspecial(pud_t pud)
{
return pud;
}
#endif /* CONFIG_ARCH_SUPPORTS_PUD_PFNMAP */
#ifndef CONFIG_ARCH_HAS_PTE_DEVMAP
static inline int pte_devmap(pte_t pte)
{
return 0;
}
#endif
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 */
static inline struct ptdesc *virt_to_ptdesc(const void *x)
{
return page_ptdesc(virt_to_page(x));
}
static inline void *ptdesc_to_virt(const struct ptdesc *pt)
{
return page_to_virt(ptdesc_page(pt));
}
static inline void *ptdesc_address(const struct ptdesc *pt)
{
return folio_address(ptdesc_folio(pt));
}
static inline bool pagetable_is_reserved(struct ptdesc *pt)
{
return folio_test_reserved(ptdesc_folio(pt));
}
/**
* pagetable_alloc - Allocate pagetables
* @gfp: GFP flags
* @order: desired pagetable order
*
* pagetable_alloc allocates memory for page tables as well as a page table
* descriptor to describe that memory.
*
* Return: The ptdesc describing the allocated page tables.
*/
static inline struct ptdesc *pagetable_alloc_noprof(gfp_t gfp, unsigned int order)
{
struct page *page = alloc_pages_noprof(gfp | __GFP_COMP, order);
return page_ptdesc(page);
}
#define pagetable_alloc(...) alloc_hooks(pagetable_alloc_noprof(__VA_ARGS__))
/**
* pagetable_free - Free pagetables
* @pt: The page table descriptor
*
* pagetable_free frees the memory of all page tables described by a page
* table descriptor and the memory for the descriptor itself.
*/
static inline void pagetable_free(struct ptdesc *pt)
{
struct page *page = ptdesc_page(pt);
__free_pages(page, compound_order(page));
}
#if defined(CONFIG_SPLIT_PTE_PTLOCKS)
#if ALLOC_SPLIT_PTLOCKS
void __init ptlock_cache_init(void);
bool ptlock_alloc(struct ptdesc *ptdesc);
void ptlock_free(struct ptdesc *ptdesc);
static inline spinlock_t *ptlock_ptr(struct ptdesc *ptdesc)
{
return ptdesc->ptl;
}
#else /* ALLOC_SPLIT_PTLOCKS */
static inline void ptlock_cache_init(void)
{
}
static inline bool ptlock_alloc(struct ptdesc *ptdesc)
{
return true;
}
static inline void ptlock_free(struct ptdesc *ptdesc)
{
}
static inline spinlock_t *ptlock_ptr(struct ptdesc *ptdesc)
{
return &ptdesc->ptl;
}
#endif /* ALLOC_SPLIT_PTLOCKS */
static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
{
return ptlock_ptr(page_ptdesc(pmd_page(*pmd)));
}
static inline spinlock_t *ptep_lockptr(struct mm_struct *mm, pte_t *pte)
{
BUILD_BUG_ON(IS_ENABLED(CONFIG_HIGHPTE));
BUILD_BUG_ON(MAX_PTRS_PER_PTE * sizeof(pte_t) > PAGE_SIZE);
return ptlock_ptr(virt_to_ptdesc(pte));
}
static inline bool ptlock_init(struct ptdesc *ptdesc)
{
/*
* 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 *)&ptdesc->ptl, ptdesc_page(ptdesc));
if (!ptlock_alloc(ptdesc))
return false;
spin_lock_init(ptlock_ptr(ptdesc));
return true;
}
#else /* !defined(CONFIG_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 spinlock_t *ptep_lockptr(struct mm_struct *mm, pte_t *pte)
{
return &mm->page_table_lock;
}
static inline void ptlock_cache_init(void) {}
static inline bool ptlock_init(struct ptdesc *ptdesc) { return true; }
static inline void ptlock_free(struct ptdesc *ptdesc) {}
#endif /* defined(CONFIG_SPLIT_PTE_PTLOCKS) */
static inline bool pagetable_pte_ctor(struct ptdesc *ptdesc)
{
struct folio *folio = ptdesc_folio(ptdesc);
if (!ptlock_init(ptdesc))
return false;
__folio_set_pgtable(folio);
lruvec_stat_add_folio(folio, NR_PAGETABLE);
return true;
}
static inline void pagetable_pte_dtor(struct ptdesc *ptdesc)
{
struct folio *folio = ptdesc_folio(ptdesc);
ptlock_free(ptdesc);
__folio_clear_pgtable(folio);
lruvec_stat_sub_folio(folio, NR_PAGETABLE);
}
pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp);
static inline pte_t *pte_offset_map(pmd_t *pmd, unsigned long addr)
{
return __pte_offset_map(pmd, addr, NULL);
}
pte_t *__pte_offset_map_lock(struct mm_struct *mm, pmd_t *pmd,
unsigned long addr, spinlock_t **ptlp);
static inline pte_t *pte_offset_map_lock(struct mm_struct *mm, pmd_t *pmd,
unsigned long addr, spinlock_t **ptlp)
{
pte_t *pte;
__cond_lock(*ptlp, pte = __pte_offset_map_lock(mm, pmd, addr, ptlp));
return pte;
}
pte_t *pte_offset_map_nolock(struct mm_struct *mm, pmd_t *pmd,
unsigned long addr, spinlock_t **ptlp);
#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 defined(CONFIG_SPLIT_PMD_PTLOCKS)
static inline struct page *pmd_pgtable_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 struct ptdesc *pmd_ptdesc(pmd_t *pmd)
{
return page_ptdesc(pmd_pgtable_page(pmd));
}
static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
{
return ptlock_ptr(pmd_ptdesc(pmd));
}
static inline bool pmd_ptlock_init(struct ptdesc *ptdesc)
{
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
ptdesc->pmd_huge_pte = NULL;
#endif
return ptlock_init(ptdesc);
}
static inline void pmd_ptlock_free(struct ptdesc *ptdesc)
{
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
VM_BUG_ON_PAGE(ptdesc->pmd_huge_pte, ptdesc_page(ptdesc));
#endif
ptlock_free(ptdesc);
}
#define pmd_huge_pte(mm, pmd) (pmd_ptdesc(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 ptdesc *ptdesc) { return true; }
static inline void pmd_ptlock_free(struct ptdesc *ptdesc) {}
#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 pagetable_pmd_ctor(struct ptdesc *ptdesc)
{
struct folio *folio = ptdesc_folio(ptdesc);
if (!pmd_ptlock_init(ptdesc))
return false;
__folio_set_pgtable(folio);
lruvec_stat_add_folio(folio, NR_PAGETABLE);
return true;
}
static inline void pagetable_pmd_dtor(struct ptdesc *ptdesc)
{
struct folio *folio = ptdesc_folio(ptdesc);
pmd_ptlock_free(ptdesc);
__folio_clear_pgtable(folio);
lruvec_stat_sub_folio(folio, 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;
}
static inline void pagetable_pud_ctor(struct ptdesc *ptdesc)
{
struct folio *folio = ptdesc_folio(ptdesc);
__folio_set_pgtable(folio);
lruvec_stat_add_folio(folio, NR_PAGETABLE);
}
static inline void pagetable_pud_dtor(struct ptdesc *ptdesc)
{
struct folio *folio = ptdesc_folio(ptdesc);
__folio_clear_pgtable(folio);
lruvec_stat_sub_folio(folio, NR_PAGETABLE);
}
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 reserve_bootmem_region(phys_addr_t start,
phys_addr_t end, int nid);
/* Free the reserved page into the buddy system, so it gets managed. */
void free_reserved_page(struct page *page);
#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);
}
static inline void free_reserved_ptdesc(struct ptdesc *pt)
{
free_reserved_page(ptdesc_page(pt));
}
/*
* 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);
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 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(void)
{
__show_mem(0, NULL, 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);
extern __printf(3, 4)
void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...);
extern void setup_per_cpu_pageset(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 insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
extern void exit_mmap(struct mm_struct *);
int relocate_vma_down(struct vm_area_struct *vma, unsigned long shift);
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);
unsigned long randomize_stack_top(unsigned long stack_top);
unsigned long randomize_page(unsigned long start, unsigned long range);
unsigned long
__get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags);
static inline unsigned long
get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
unsigned long pgoff, unsigned long flags)
{
return __get_unmapped_area(file, addr, len, pgoff, flags, 0);
}
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,
vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate,
struct list_head *uf);
extern int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm,
unsigned long start, size_t len, struct list_head *uf,
bool unlock);
int do_vmi_align_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma,
struct mm_struct *mm, unsigned long start,
unsigned long end, struct list_head *uf, bool unlock);
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
/* This takes the mm semaphore itself */
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;
unsigned long start_gap;
};
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 stack_guard_start_gap(struct vm_area_struct *vma)
{
if (vma->vm_flags & VM_GROWSDOWN)
return stack_guard_gap;
/* See reasoning around the VM_SHADOW_STACK definition */
if (vma->vm_flags & VM_SHADOW_STACK)
return PAGE_SIZE;
return 0;
}
static inline unsigned long vm_start_gap(struct vm_area_struct *vma)
{
unsigned long gap = stack_guard_start_gap(vma);
unsigned long vm_start = vma->vm_start;
vm_start -= gap;
if (vm_start > vma->vm_start)
vm_start = 0;
return vm_start;
}
static inline unsigned long vm_end_gap(struct vm_area_struct *vma)
{
unsigned long vm_end = vma->vm_end;
if (vma->vm_flags & VM_GROWSUP) {
vm_end += stack_guard_gap;
if (vm_end < vma->vm_end)
vm_end = -PAGE_SIZE;
}
return vm_end;
}
static inline unsigned long vma_pages(struct vm_area_struct *vma)
{
return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
}
/* Look up the first VMA which exactly match the interval vm_start ... vm_end */
static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
unsigned long vm_start, unsigned long vm_end)
{
struct vm_area_struct *vma = vma_lookup(mm, vm_start);
if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
vma = NULL;
return vma;
}
static inline bool range_in_vma(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
return (vma && vma->vm_start <= start && end <= vma->vm_end);
}
#ifdef CONFIG_MMU
pgprot_t vm_get_page_prot(unsigned long vm_flags);
void vma_set_page_prot(struct vm_area_struct *vma);
#else
static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
{
return __pgprot(0);
}
static inline void vma_set_page_prot(struct vm_area_struct *vma)
{
vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
}
#endif
void vma_set_file(struct vm_area_struct *vma, struct file *file);
#ifdef CONFIG_NUMA_BALANCING
unsigned long change_prot_numa(struct vm_area_struct *vma,
unsigned long start, unsigned long end);
#endif
struct vm_area_struct *find_extend_vma_locked(struct mm_struct *,
unsigned long addr);
int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
unsigned long pfn, unsigned long size, pgprot_t);
int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr,
unsigned long pfn, unsigned long size, pgprot_t prot);
int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr,
struct page **pages, unsigned long *num);
int vm_map_pages(struct vm_area_struct *vma, struct page **pages,
unsigned long num);
int vm_map_pages_zero(struct vm_area_struct *vma, struct page **pages,
unsigned long num);
vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
unsigned long pfn);
vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
unsigned long pfn, pgprot_t pgprot);
vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
pfn_t pfn);
vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
unsigned long addr, pfn_t pfn);
int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
static inline vm_fault_t vmf_insert_page(struct vm_area_struct *vma,
unsigned long addr, struct page *page)
{
int err = vm_insert_page(vma, addr, page);
if (err == -ENOMEM)
return VM_FAULT_OOM;
if (err < 0 && err != -EBUSY)
return VM_FAULT_SIGBUS;
return VM_FAULT_NOPAGE;
}
#ifndef io_remap_pfn_range
static inline int io_remap_pfn_range(struct vm_area_struct *vma,
unsigned long addr, unsigned long pfn,
unsigned long size, pgprot_t prot)
{
return remap_pfn_range(vma, addr, pfn, size, pgprot_decrypted(prot));
}
#endif
static inline vm_fault_t vmf_error(int err)
{
if (err == -ENOMEM)
return VM_FAULT_OOM;
else if (err == -EHWPOISON)
return VM_FAULT_HWPOISON;
return VM_FAULT_SIGBUS;
}
/*
* Convert errno to return value for ->page_mkwrite() calls.
*
* This should eventually be merged with vmf_error() above, but will need a
* careful audit of all vmf_error() callers.
*/
static inline vm_fault_t vmf_fs_error(int err)
{
if (err == 0)
return VM_FAULT_LOCKED;
if (err == -EFAULT || err == -EAGAIN)
return VM_FAULT_NOPAGE;
if (err == -ENOMEM)
return VM_FAULT_OOM;
/* -ENOSPC, -EDQUOT, -EIO ... */
return VM_FAULT_SIGBUS;
}
static inline int vm_fault_to_errno(vm_fault_t vm_fault, int foll_flags)
{
if (vm_fault & VM_FAULT_OOM)
return -ENOMEM;
if (vm_fault & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE))
return (foll_flags & FOLL_HWPOISON) ? -EHWPOISON : -EFAULT;
if (vm_fault & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV))
return -EFAULT;
return 0;
}
/*
* Indicates whether GUP can follow a PROT_NONE mapped page, or whether
* a (NUMA hinting) fault is required.
*/
static inline bool gup_can_follow_protnone(struct vm_area_struct *vma,
unsigned int flags)
{
/*
* If callers don't want to honor NUMA hinting faults, no need to
* determine if we would actually have to trigger a NUMA hinting fault.
*/
if (!(flags & FOLL_HONOR_NUMA_FAULT))
return true;
/*
* NUMA hinting faults don't apply in inaccessible (PROT_NONE) VMAs.
*
* Requiring a fault here even for inaccessible VMAs would mean that
* FOLL_FORCE cannot make any progress, because handle_mm_fault()
* refuses to process NUMA hinting faults in inaccessible VMAs.
*/
return !vma_is_accessible(vma);
}
typedef int (*pte_fn_t)(pte_t *pte, unsigned long addr, void *data);
extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
unsigned long size, pte_fn_t fn, void *data);
extern int apply_to_existing_page_range(struct mm_struct *mm,
unsigned long address, unsigned long size,
pte_fn_t fn, void *data);
#ifdef CONFIG_PAGE_POISONING
extern void __kernel_poison_pages(struct page *page, int numpages);
extern void __kernel_unpoison_pages(struct page *page, int numpages);
extern bool _page_poisoning_enabled_early;
DECLARE_STATIC_KEY_FALSE(_page_poisoning_enabled);
static inline bool page_poisoning_enabled(void)
{
return _page_poisoning_enabled_early;
}
/*
* For use in fast paths after init_mem_debugging() has run, or when a
* false negative result is not harmful when called too early.
*/
static inline bool page_poisoning_enabled_static(void)
{
return static_branch_unlikely(&_page_poisoning_enabled);
}
static inline void kernel_poison_pages(struct page *page, int numpages)
{
if (page_poisoning_enabled_static())
__kernel_poison_pages(page, numpages);
}
static inline void kernel_unpoison_pages(struct page *page, int numpages)
{
if (page_poisoning_enabled_static())
__kernel_unpoison_pages(page, numpages);
}
#else
static inline bool page_poisoning_enabled(void) { return false; }
static inline bool page_poisoning_enabled_static(void) { return false; }
static inline void __kernel_poison_pages(struct page *page, int nunmpages) { }
static inline void kernel_poison_pages(struct page *page, int numpages) { }
static inline void kernel_unpoison_pages(struct page *page, int numpages) { }
#endif
DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
static inline bool want_init_on_alloc(gfp_t flags)
{
if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
&init_on_alloc))
return true;
return flags & __GFP_ZERO;
}
DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free);
static inline bool want_init_on_free(void)
{
return static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
&init_on_free);
}
extern bool _debug_pagealloc_enabled_early;
DECLARE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
static inline bool debug_pagealloc_enabled(void)
{
return IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) &&
_debug_pagealloc_enabled_early;
}
/*
* For use in fast paths after mem_debugging_and_hardening_init() has run,
* or when a false negative result is not harmful when called too early.
*/
static inline bool debug_pagealloc_enabled_static(void)
{
if (!IS_ENABLED(CONFIG_DEBUG_PAGEALLOC))
return false;
return static_branch_unlikely(&_debug_pagealloc_enabled);
}
/*
* To support DEBUG_PAGEALLOC architecture must ensure that
* __kernel_map_pages() never fails
*/
extern void __kernel_map_pages(struct page *page, int numpages, int enable);
#ifdef CONFIG_DEBUG_PAGEALLOC
static inline void debug_pagealloc_map_pages(struct page *page, int numpages)
{
if (debug_pagealloc_enabled_static())
__kernel_map_pages(page, numpages, 1);
}
static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages)
{
if (debug_pagealloc_enabled_static())
__kernel_map_pages(page, numpages, 0);
}
extern unsigned int _debug_guardpage_minorder;
DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
static inline unsigned int debug_guardpage_minorder(void)
{
return _debug_guardpage_minorder;
}
static inline bool debug_guardpage_enabled(void)
{
return static_branch_unlikely(&_debug_guardpage_enabled);
}
static inline bool page_is_guard(struct page *page)
{
if (!debug_guardpage_enabled())
return false;
return PageGuard(page);
}
bool __set_page_guard(struct zone *zone, struct page *page, unsigned int order);
static inline bool set_page_guard(struct zone *zone, struct page *page,
unsigned int order)
{
if (!debug_guardpage_enabled())
return false;
return __set_page_guard(zone, page, order);
}
void __clear_page_guard(struct zone *zone, struct page *page, unsigned int order);
static inline void clear_page_guard(struct zone *zone, struct page *page,
unsigned int order)
{
if (!debug_guardpage_enabled())
return;
__clear_page_guard(zone, page, order);
}
#else /* CONFIG_DEBUG_PAGEALLOC */
static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {}
static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {}
static inline unsigned int debug_guardpage_minorder(void) { return 0; }
static inline bool debug_guardpage_enabled(void) { return false; }
static inline bool page_is_guard(struct page *page) { return false; }
static inline bool set_page_guard(struct zone *zone, struct page *page,
unsigned int order) { return false; }
static inline void clear_page_guard(struct zone *zone, struct page *page,
unsigned int order) {}
#endif /* CONFIG_DEBUG_PAGEALLOC */
#ifdef __HAVE_ARCH_GATE_AREA
extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
extern int in_gate_area_no_mm(unsigned long addr);
extern int in_gate_area(struct mm_struct *mm, unsigned long addr);
#else
static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
{
return NULL;
}
static inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
{
return 0;
}
#endif /* __HAVE_ARCH_GATE_AREA */
extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm);
#ifdef CONFIG_SYSCTL
extern int sysctl_drop_caches;
int drop_caches_sysctl_handler(const struct ctl_table *, int, void *, size_t *,
loff_t *);
#endif
void drop_slab(void);
#ifndef CONFIG_MMU
#define randomize_va_space 0
#else
extern int randomize_va_space;
#endif
const char * arch_vma_name(struct vm_area_struct *vma);
#ifdef CONFIG_MMU
void print_vma_addr(char *prefix, unsigned long rip);
#else
static inline void print_vma_addr(char *prefix, unsigned long rip)
{
}
#endif
void *sparse_buffer_alloc(unsigned long size);
struct page * __populate_section_memmap(unsigned long pfn,
unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
struct dev_pagemap *pgmap);
void pmd_init(void *addr);
void pud_init(void *addr);
pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node);
pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node);
pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
struct vmem_altmap *altmap, struct page *reuse);
void *vmemmap_alloc_block(unsigned long size, int node);
struct vmem_altmap;
void *vmemmap_alloc_block_buf(unsigned long size, int node,
struct vmem_altmap *altmap);
void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
void vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
unsigned long addr, unsigned long next);
int vmemmap_check_pmd(pmd_t *pmd, int node,
unsigned long addr, unsigned long next);
int vmemmap_populate_basepages(unsigned long start, unsigned long end,
int node, struct vmem_altmap *altmap);
int vmemmap_populate_hugepages(unsigned long start, unsigned long end,
int node, struct vmem_altmap *altmap);
int vmemmap_populate(unsigned long start, unsigned long end, int node,
struct vmem_altmap *altmap);
void vmemmap_populate_print_last(void);
#ifdef CONFIG_MEMORY_HOTPLUG
void vmemmap_free(unsigned long start, unsigned long end,
struct vmem_altmap *altmap);
#endif
#ifdef CONFIG_SPARSEMEM_VMEMMAP
static inline unsigned long vmem_altmap_offset(struct vmem_altmap *altmap)
{
/* number of pfns from base where pfn_to_page() is valid */
if (altmap)
return altmap->reserve + altmap->free;
return 0;
}
static inline void vmem_altmap_free(struct vmem_altmap *altmap,
unsigned long nr_pfns)
{
altmap->alloc -= nr_pfns;
}
#else
static inline unsigned long vmem_altmap_offset(struct vmem_altmap *altmap)
{
return 0;
}
static inline void vmem_altmap_free(struct vmem_altmap *altmap,
unsigned long nr_pfns)
{
}
#endif
#define VMEMMAP_RESERVE_NR 2
#ifdef CONFIG_ARCH_WANT_OPTIMIZE_DAX_VMEMMAP
static inline bool __vmemmap_can_optimize(struct vmem_altmap *altmap,
struct dev_pagemap *pgmap)
{
unsigned long nr_pages;
unsigned long nr_vmemmap_pages;
if (!pgmap || !is_power_of_2(sizeof(struct page)))
return false;
nr_pages = pgmap_vmemmap_nr(pgmap);
nr_vmemmap_pages = ((nr_pages * sizeof(struct page)) >> PAGE_SHIFT);
/*
* For vmemmap optimization with DAX we need minimum 2 vmemmap
* pages. See layout diagram in Documentation/mm/vmemmap_dedup.rst
*/
return !altmap && (nr_vmemmap_pages > VMEMMAP_RESERVE_NR);
}
/*
* If we don't have an architecture override, use the generic rule
*/
#ifndef vmemmap_can_optimize
#define vmemmap_can_optimize __vmemmap_can_optimize
#endif
#else
static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap,
struct dev_pagemap *pgmap)
{
return false;
}
#endif
void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
unsigned long nr_pages);
enum mf_flags {
MF_COUNT_INCREASED = 1 << 0,
MF_ACTION_REQUIRED = 1 << 1,
MF_MUST_KILL = 1 << 2,
MF_SOFT_OFFLINE = 1 << 3,
MF_UNPOISON = 1 << 4,
MF_SW_SIMULATED = 1 << 5,
MF_NO_RETRY = 1 << 6,
MF_MEM_PRE_REMOVE = 1 << 7,
};
int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index,
unsigned long count, int mf_flags);
extern int memory_failure(unsigned long pfn, int flags);
extern void memory_failure_queue_kick(int cpu);
extern int unpoison_memory(unsigned long pfn);
extern atomic_long_t num_poisoned_pages __read_mostly;
extern int soft_offline_page(unsigned long pfn, int flags);
#ifdef CONFIG_MEMORY_FAILURE
/*
* Sysfs entries for memory failure handling statistics.
*/
extern const struct attribute_group memory_failure_attr_group;
extern void memory_failure_queue(unsigned long pfn, int flags);
extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared);
void num_poisoned_pages_inc(unsigned long pfn);
void num_poisoned_pages_sub(unsigned long pfn, long i);
#else
static inline void memory_failure_queue(unsigned long pfn, int flags)
{
}
static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared)
{
return 0;
}
static inline void num_poisoned_pages_inc(unsigned long pfn)
{
}
static inline void num_poisoned_pages_sub(unsigned long pfn, long i)
{
}
#endif
#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG)
extern void memblk_nr_poison_inc(unsigned long pfn);
extern void memblk_nr_poison_sub(unsigned long pfn, long i);
#else
static inline void memblk_nr_poison_inc(unsigned long pfn)
{
}
static inline void memblk_nr_poison_sub(unsigned long pfn, long i)
{
}
#endif
#ifndef arch_memory_failure
static inline int arch_memory_failure(unsigned long pfn, int flags)
{
return -ENXIO;
}
#endif
#ifndef arch_is_platform_page
static inline bool arch_is_platform_page(u64 paddr)
{
return false;
}
#endif
/*
* Error handlers for various types of pages.
*/
enum mf_result {
MF_IGNORED, /* Error: cannot be handled */
MF_FAILED, /* Error: handling failed */
MF_DELAYED, /* Will be handled later */
MF_RECOVERED, /* Successfully recovered */
};
enum mf_action_page_type {
MF_MSG_KERNEL,
MF_MSG_KERNEL_HIGH_ORDER,
MF_MSG_DIFFERENT_COMPOUND,
MF_MSG_HUGE,
MF_MSG_FREE_HUGE,
MF_MSG_GET_HWPOISON,
MF_MSG_UNMAP_FAILED,
MF_MSG_DIRTY_SWAPCACHE,
MF_MSG_CLEAN_SWAPCACHE,
MF_MSG_DIRTY_MLOCKED_LRU,
MF_MSG_CLEAN_MLOCKED_LRU,
MF_MSG_DIRTY_UNEVICTABLE_LRU,
MF_MSG_CLEAN_UNEVICTABLE_LRU,
MF_MSG_DIRTY_LRU,
MF_MSG_CLEAN_LRU,
MF_MSG_TRUNCATED_LRU,
MF_MSG_BUDDY,
MF_MSG_DAX,
MF_MSG_UNSPLIT_THP,
MF_MSG_ALREADY_POISONED,
MF_MSG_UNKNOWN,
};
#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
void folio_zero_user(struct folio *folio, unsigned long addr_hint);
int copy_user_large_folio(struct folio *dst, struct folio *src,
unsigned long addr_hint,
struct vm_area_struct *vma);
long copy_folio_from_user(struct folio *dst_folio,
const void __user *usr_src,
bool allow_pagefault);
/**
* vma_is_special_huge - Are transhuge page-table entries considered special?
* @vma: Pointer to the struct vm_area_struct to consider
*
* Whether transhuge page-table entries are considered "special" following
* the definition in vm_normal_page().
*
* Return: true if transhuge page-table entries should be considered special,
* false otherwise.
*/
static inline bool vma_is_special_huge(const struct vm_area_struct *vma)
{
return vma_is_dax(vma) || (vma->vm_file &&
(vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)));
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
#if MAX_NUMNODES > 1
void __init setup_nr_node_ids(void);
#else
static inline void setup_nr_node_ids(void) {}
#endif
extern int memcmp_pages(struct page *page1, struct page *page2);
static inline int pages_identical(struct page *page1, struct page *page2)
{
return !memcmp_pages(page1, page2);
}
#ifdef CONFIG_MAPPING_DIRTY_HELPERS
unsigned long clean_record_shared_mapping_range(struct address_space *mapping,
pgoff_t first_index, pgoff_t nr,
pgoff_t bitmap_pgoff,
unsigned long *bitmap,
pgoff_t *start,
pgoff_t *end);
unsigned long wp_shared_mapping_range(struct address_space *mapping,
pgoff_t first_index, pgoff_t nr);
#endif
extern int sysctl_nr_trim_pages;
#ifdef CONFIG_PRINTK
void mem_dump_obj(void *object);
#else
static inline void mem_dump_obj(void *object) {}
#endif
/**
* seal_check_write - Check for F_SEAL_WRITE or F_SEAL_FUTURE_WRITE flags and
* handle them.
* @seals: the seals to check
* @vma: the vma to operate on
*
* Check whether F_SEAL_WRITE or F_SEAL_FUTURE_WRITE are set; if so, do proper
* check/handling on the vma flags. Return 0 if check pass, or <0 for errors.
*/
static inline int seal_check_write(int seals, struct vm_area_struct *vma)
{
if (seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) {
/*
* New PROT_WRITE and MAP_SHARED mmaps are not allowed when
* write seals are active.
*/
if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE))
return -EPERM;
/*
* Since an F_SEAL_[FUTURE_]WRITE sealed memfd can be mapped as
* MAP_SHARED and read-only, take care to not allow mprotect to
* revert protections on such mappings. Do this only for shared
* mappings. For private mappings, don't need to mask
* VM_MAYWRITE as we still want them to be COW-writable.
*/
if (vma->vm_flags & VM_SHARED)
vm_flags_clear(vma, VM_MAYWRITE);
}
return 0;
}
#ifdef CONFIG_ANON_VMA_NAME
int madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
unsigned long len_in,
struct anon_vma_name *anon_name);
#else
static inline int
madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
unsigned long len_in, struct anon_vma_name *anon_name) {
return 0;
}
#endif
#ifdef CONFIG_UNACCEPTED_MEMORY
bool range_contains_unaccepted_memory(phys_addr_t start, unsigned long size);
void accept_memory(phys_addr_t start, unsigned long size);
#else
static inline bool range_contains_unaccepted_memory(phys_addr_t start,
unsigned long size)
{
return false;
}
static inline void accept_memory(phys_addr_t start, unsigned long size)
{
}
#endif
static inline bool pfn_is_unaccepted_memory(unsigned long pfn)
{
return range_contains_unaccepted_memory(pfn << PAGE_SHIFT, PAGE_SIZE);
}
void vma_pgtable_walk_begin(struct vm_area_struct *vma);
void vma_pgtable_walk_end(struct vm_area_struct *vma);
int reserve_mem_find_by_name(const char *name, phys_addr_t *start, phys_addr_t *size);
#ifdef CONFIG_64BIT
int do_mseal(unsigned long start, size_t len_in, unsigned long flags);
#else
static inline int do_mseal(unsigned long start, size_t len_in, unsigned long flags)
{
/* noop on 32 bit */
return 0;
}
#endif
#ifdef CONFIG_MEM_ALLOC_PROFILING
static inline void pgalloc_tag_split(struct folio *folio, int old_order, int new_order)
{
int i;
struct alloc_tag *tag;
unsigned int nr_pages = 1 << new_order;
if (!mem_alloc_profiling_enabled())
return;
tag = pgalloc_tag_get(&folio->page);
if (!tag)
return;
for (i = nr_pages; i < (1 << old_order); i += nr_pages) {
union codetag_ref *ref = get_page_tag_ref(folio_page(folio, i));
if (ref) {
/* Set new reference to point to the original tag */
alloc_tag_ref_set(ref, tag);
put_page_tag_ref(ref);
}
}
}
static inline void pgalloc_tag_copy(struct folio *new, struct folio *old)
{
struct alloc_tag *tag;
union codetag_ref *ref;
tag = pgalloc_tag_get(&old->page);
if (!tag)
return;
ref = get_page_tag_ref(&new->page);
if (!ref)
return;
/* Clear the old ref to the original allocation tag. */
clear_page_tag_ref(&old->page);
/* Decrement the counters of the tag on get_new_folio. */
alloc_tag_sub(ref, folio_nr_pages(new));
__alloc_tag_ref_set(ref, tag);
put_page_tag_ref(ref);
}
#else /* !CONFIG_MEM_ALLOC_PROFILING */
static inline void pgalloc_tag_split(struct folio *folio, int old_order, int new_order)
{
}
static inline void pgalloc_tag_copy(struct folio *new, struct folio *old)
{
}
#endif /* CONFIG_MEM_ALLOC_PROFILING */
#endif /* _LINUX_MM_H */