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linux/linux/kernel/git/klassert/ipsec/dd56c0bc4836fa705acb2f6a8a44af669d30fa3a/./include/linux/mm.h
blob: dd09c438fa23ec8d3980ece2e8d833a3c5598f48 [file]
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_MM_H
#define _LINUX_MM_H
#include <linux/args.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/compiler.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/sched.h>
#include <linux/pgtable.h>
#include <linux/kasan.h>
#include <linux/memremap.h>
#include <linux/slab.h>
#include <linux/cacheinfo.h>
#include <linux/rcuwait.h>
#include <linux/bitmap.h>
#include <linux/bitops.h>
#include <linux/iommu-debug-pagealloc.h>
#include <linux/kcsan-checks.h>
struct mempolicy;
struct anon_vma;
struct anon_vma_chain;
struct user_struct;
struct pt_regs;
struct folio_batch;
void arch_mm_preinit(void);
void mm_core_init_early(void);
void mm_core_init(void);
void init_mm_internals(void);
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;
/*
* Convert between pages and MB
* 20 is the shift for 1MB (2^20 = 1MB)
* PAGE_SHIFT is the shift for page size (e.g., 12 for 4KB pages)
* So (20 - PAGE_SHIFT) converts between pages and MB
*/
#define PAGES_TO_MB(pages) ((pages) >> (20 - PAGE_SHIFT))
#define MB_TO_PAGES(mb) ((mb) << (20 - PAGE_SHIFT))
#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 DIRECT_MAP_PHYSMEM_END
# ifdef MAX_PHYSMEM_BITS
# define DIRECT_MAP_PHYSMEM_END ((1ULL << MAX_PHYSMEM_BITS) - 1)
# else
# define DIRECT_MAP_PHYSMEM_END (((phys_addr_t)-1)&~(1ULL<<63))
# endif
#endif
#define INVALID_PHYS_ADDR (~(phys_addr_t)0)
#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 unsigned long sysctl_user_reserve_kbytes;
extern unsigned long sysctl_admin_reserve_kbytes;
#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
bool page_range_contiguous(const struct page *page, unsigned long nr_pages);
#else
static inline bool page_range_contiguous(const struct page *page,
unsigned long nr_pages)
{
return true;
}
#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)
/**
* folio_page_idx - Return the number of a page in a folio.
* @folio: The folio.
* @page: The folio page.
*
* This function expects that the page is actually part of the folio.
* The returned number is relative to the start of the folio.
*/
static inline unsigned long folio_page_idx(const struct folio *folio,
const struct page *page)
{
return page - &folio->page;
}
static inline struct folio *lru_to_folio(struct list_head *head)
{
return list_entry((head)->prev, struct folio, lru);
}
void setup_initial_init_mm(void *start_code, void *end_code,
void *end_data, void *brk);
/*
* Linux kernel virtual memory manager primitives.
* The idea being to have a "virtual" mm in the same way
* we have a virtual fs - giving a cleaner interface to the
* mm details, and allowing different kinds of memory mappings
* (from shared memory to executable loading to arbitrary
* mmap() functions).
*/
struct vm_area_struct *vm_area_alloc(struct mm_struct *);
struct vm_area_struct *vm_area_dup(struct vm_area_struct *);
void vm_area_free(struct vm_area_struct *);
#ifndef CONFIG_MMU
extern struct rb_root nommu_region_tree;
extern struct rw_semaphore nommu_region_sem;
extern unsigned int kobjsize(const void *objp);
#endif
/*
* vm_flags in vm_area_struct, see mm_types.h.
* When changing, update also include/trace/events/mmflags.h
*/
#define VM_NONE 0x00000000
/**
* typedef vma_flag_t - specifies an individual VMA flag by bit number.
*
* This value is made type safe by sparse to avoid passing invalid flag values
* around.
*/
typedef int __bitwise vma_flag_t;
#define DECLARE_VMA_BIT(name, bitnum) \
VMA_ ## name ## _BIT = ((__force vma_flag_t)bitnum)
#define DECLARE_VMA_BIT_ALIAS(name, aliased) \
VMA_ ## name ## _BIT = (VMA_ ## aliased ## _BIT)
enum {
DECLARE_VMA_BIT(READ, 0),
DECLARE_VMA_BIT(WRITE, 1),
DECLARE_VMA_BIT(EXEC, 2),
DECLARE_VMA_BIT(SHARED, 3),
/* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
DECLARE_VMA_BIT(MAYREAD, 4), /* limits for mprotect() etc. */
DECLARE_VMA_BIT(MAYWRITE, 5),
DECLARE_VMA_BIT(MAYEXEC, 6),
DECLARE_VMA_BIT(MAYSHARE, 7),
DECLARE_VMA_BIT(GROWSDOWN, 8), /* general info on the segment */
#ifdef CONFIG_MMU
DECLARE_VMA_BIT(UFFD_MISSING, 9),/* missing pages tracking */
#else
/* nommu: R/O MAP_PRIVATE mapping that might overlay a file mapping */
DECLARE_VMA_BIT(MAYOVERLAY, 9),
#endif /* CONFIG_MMU */
/* Page-ranges managed without "struct page", just pure PFN */
DECLARE_VMA_BIT(PFNMAP, 10),
DECLARE_VMA_BIT(MAYBE_GUARD, 11),
DECLARE_VMA_BIT(UFFD_WP, 12), /* wrprotect pages tracking */
DECLARE_VMA_BIT(LOCKED, 13),
DECLARE_VMA_BIT(IO, 14), /* Memory mapped I/O or similar */
DECLARE_VMA_BIT(SEQ_READ, 15), /* App will access data sequentially */
DECLARE_VMA_BIT(RAND_READ, 16), /* App will not benefit from clustered reads */
DECLARE_VMA_BIT(DONTCOPY, 17), /* Do not copy this vma on fork */
DECLARE_VMA_BIT(DONTEXPAND, 18),/* Cannot expand with mremap() */
DECLARE_VMA_BIT(LOCKONFAULT, 19),/* Lock pages covered when faulted in */
DECLARE_VMA_BIT(ACCOUNT, 20), /* Is a VM accounted object */
DECLARE_VMA_BIT(NORESERVE, 21), /* should the VM suppress accounting */
DECLARE_VMA_BIT(HUGETLB, 22), /* Huge TLB Page VM */
DECLARE_VMA_BIT(SYNC, 23), /* Synchronous page faults */
DECLARE_VMA_BIT(ARCH_1, 24), /* Architecture-specific flag */
DECLARE_VMA_BIT(WIPEONFORK, 25),/* Wipe VMA contents in child. */
DECLARE_VMA_BIT(DONTDUMP, 26), /* Do not include in the core dump */
DECLARE_VMA_BIT(SOFTDIRTY, 27), /* NOT soft dirty clean area */
DECLARE_VMA_BIT(MIXEDMAP, 28), /* Can contain struct page and pure PFN pages */
DECLARE_VMA_BIT(HUGEPAGE, 29), /* MADV_HUGEPAGE marked this vma */
DECLARE_VMA_BIT(NOHUGEPAGE, 30),/* MADV_NOHUGEPAGE marked this vma */
DECLARE_VMA_BIT(MERGEABLE, 31), /* KSM may merge identical pages */
/* These bits are reused, we define specific uses below. */
DECLARE_VMA_BIT(HIGH_ARCH_0, 32),
DECLARE_VMA_BIT(HIGH_ARCH_1, 33),
DECLARE_VMA_BIT(HIGH_ARCH_2, 34),
DECLARE_VMA_BIT(HIGH_ARCH_3, 35),
DECLARE_VMA_BIT(HIGH_ARCH_4, 36),
DECLARE_VMA_BIT(HIGH_ARCH_5, 37),
DECLARE_VMA_BIT(HIGH_ARCH_6, 38),
/*
* 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.
*/
DECLARE_VMA_BIT(ALLOW_ANY_UNCACHED, 39),
#if defined(CONFIG_PPC32)
DECLARE_VMA_BIT_ALIAS(DROPPABLE, ARCH_1),
#elif defined(CONFIG_64BIT)
DECLARE_VMA_BIT(DROPPABLE, 40),
#endif
DECLARE_VMA_BIT(UFFD_MINOR, 41),
DECLARE_VMA_BIT(SEALED, 42),
DECLARE_VMA_BIT(UFFD_RWP, 43),
/* Flags that reuse flags above. */
DECLARE_VMA_BIT_ALIAS(PKEY_BIT0, HIGH_ARCH_0),
DECLARE_VMA_BIT_ALIAS(PKEY_BIT1, HIGH_ARCH_1),
DECLARE_VMA_BIT_ALIAS(PKEY_BIT2, HIGH_ARCH_2),
DECLARE_VMA_BIT_ALIAS(PKEY_BIT3, HIGH_ARCH_3),
DECLARE_VMA_BIT_ALIAS(PKEY_BIT4, HIGH_ARCH_4),
#if defined(CONFIG_X86_USER_SHADOW_STACK) || defined(CONFIG_RISCV_USER_CFI)
/*
* 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.
*/
DECLARE_VMA_BIT_ALIAS(SHADOW_STACK, HIGH_ARCH_5),
#elif defined(CONFIG_ARM64_GCS)
/*
* arm64's Guarded Control Stack implements similar functionality and
* has similar constraints to shadow stacks.
*/
DECLARE_VMA_BIT_ALIAS(SHADOW_STACK, HIGH_ARCH_6),
#endif
DECLARE_VMA_BIT_ALIAS(SAO, ARCH_1), /* Strong Access Ordering (powerpc) */
DECLARE_VMA_BIT_ALIAS(GROWSUP, ARCH_1), /* parisc */
DECLARE_VMA_BIT_ALIAS(SPARC_ADI, ARCH_1), /* sparc64 */
DECLARE_VMA_BIT_ALIAS(ARM64_BTI, ARCH_1), /* arm64 */
DECLARE_VMA_BIT_ALIAS(ARCH_CLEAR, ARCH_1), /* sparc64, arm64 */
DECLARE_VMA_BIT_ALIAS(MAPPED_COPY, ARCH_1), /* !CONFIG_MMU */
DECLARE_VMA_BIT_ALIAS(MTE, HIGH_ARCH_4), /* arm64 */
DECLARE_VMA_BIT_ALIAS(MTE_ALLOWED, HIGH_ARCH_5),/* arm64 */
#ifdef CONFIG_STACK_GROWSUP
DECLARE_VMA_BIT_ALIAS(STACK, GROWSUP),
DECLARE_VMA_BIT_ALIAS(STACK_EARLY, GROWSDOWN),
#else
DECLARE_VMA_BIT_ALIAS(STACK, GROWSDOWN),
#endif
};
#undef DECLARE_VMA_BIT
#undef DECLARE_VMA_BIT_ALIAS
#define INIT_VM_FLAG(name) BIT((__force int) VMA_ ## name ## _BIT)
#define VM_READ INIT_VM_FLAG(READ)
#define VM_WRITE INIT_VM_FLAG(WRITE)
#define VM_EXEC INIT_VM_FLAG(EXEC)
#define VM_SHARED INIT_VM_FLAG(SHARED)
#define VM_MAYREAD INIT_VM_FLAG(MAYREAD)
#define VM_MAYWRITE INIT_VM_FLAG(MAYWRITE)
#define VM_MAYEXEC INIT_VM_FLAG(MAYEXEC)
#define VM_MAYSHARE INIT_VM_FLAG(MAYSHARE)
#define VM_GROWSDOWN INIT_VM_FLAG(GROWSDOWN)
#ifdef CONFIG_MMU
#define VM_UFFD_MISSING INIT_VM_FLAG(UFFD_MISSING)
#else
#define VM_UFFD_MISSING VM_NONE
#define VM_MAYOVERLAY INIT_VM_FLAG(MAYOVERLAY)
#endif
#define VM_PFNMAP INIT_VM_FLAG(PFNMAP)
#define VM_MAYBE_GUARD INIT_VM_FLAG(MAYBE_GUARD)
#define VM_UFFD_WP INIT_VM_FLAG(UFFD_WP)
#define VM_LOCKED INIT_VM_FLAG(LOCKED)
#define VM_IO INIT_VM_FLAG(IO)
#define VM_SEQ_READ INIT_VM_FLAG(SEQ_READ)
#define VM_RAND_READ INIT_VM_FLAG(RAND_READ)
#define VM_DONTCOPY INIT_VM_FLAG(DONTCOPY)
#define VM_DONTEXPAND INIT_VM_FLAG(DONTEXPAND)
#define VM_LOCKONFAULT INIT_VM_FLAG(LOCKONFAULT)
#define VM_ACCOUNT INIT_VM_FLAG(ACCOUNT)
#define VM_NORESERVE INIT_VM_FLAG(NORESERVE)
#define VM_HUGETLB INIT_VM_FLAG(HUGETLB)
#define VM_SYNC INIT_VM_FLAG(SYNC)
#define VM_ARCH_1 INIT_VM_FLAG(ARCH_1)
#define VM_WIPEONFORK INIT_VM_FLAG(WIPEONFORK)
#define VM_DONTDUMP INIT_VM_FLAG(DONTDUMP)
#ifdef CONFIG_MEM_SOFT_DIRTY
#define VM_SOFTDIRTY INIT_VM_FLAG(SOFTDIRTY)
#else
#define VM_SOFTDIRTY VM_NONE
#endif
#define VM_MIXEDMAP INIT_VM_FLAG(MIXEDMAP)
#define VM_HUGEPAGE INIT_VM_FLAG(HUGEPAGE)
#define VM_NOHUGEPAGE INIT_VM_FLAG(NOHUGEPAGE)
#define VM_MERGEABLE INIT_VM_FLAG(MERGEABLE)
#define VM_STACK INIT_VM_FLAG(STACK)
#ifdef CONFIG_STACK_GROWSUP
#define VM_STACK_EARLY INIT_VM_FLAG(STACK_EARLY)
#define VMA_STACK_EARLY mk_vma_flags(VMA_STACK_EARLY_BIT)
#else
#define VM_STACK_EARLY VM_NONE
#define VMA_STACK_EARLY EMPTY_VMA_FLAGS
#endif
#ifdef CONFIG_ARCH_HAS_PKEYS
#define VM_PKEY_SHIFT ((__force int)VMA_HIGH_ARCH_0_BIT)
/* Despite the naming, these are FLAGS not bits. */
#define VM_PKEY_BIT0 INIT_VM_FLAG(PKEY_BIT0)
#define VM_PKEY_BIT1 INIT_VM_FLAG(PKEY_BIT1)
#define VM_PKEY_BIT2 INIT_VM_FLAG(PKEY_BIT2)
#if CONFIG_ARCH_PKEY_BITS > 3
#define VM_PKEY_BIT3 INIT_VM_FLAG(PKEY_BIT3)
#else
#define VM_PKEY_BIT3 VM_NONE
#endif /* CONFIG_ARCH_PKEY_BITS > 3 */
#if CONFIG_ARCH_PKEY_BITS > 4
#define VM_PKEY_BIT4 INIT_VM_FLAG(PKEY_BIT4)
#else
#define VM_PKEY_BIT4 VM_NONE
#endif /* CONFIG_ARCH_PKEY_BITS > 4 */
#endif /* CONFIG_ARCH_HAS_PKEYS */
#if defined(CONFIG_X86_USER_SHADOW_STACK) || defined(CONFIG_ARM64_GCS) || \
defined(CONFIG_RISCV_USER_CFI)
#define VM_SHADOW_STACK INIT_VM_FLAG(SHADOW_STACK)
#define VMA_SHADOW_STACK mk_vma_flags(VMA_SHADOW_STACK_BIT)
#define VMA_STARTGAP_FLAGS mk_vma_flags(VMA_GROWSDOWN_BIT, VMA_SHADOW_STACK_BIT)
#else
#define VM_SHADOW_STACK VM_NONE
#define VMA_SHADOW_STACK EMPTY_VMA_FLAGS
#define VMA_STARTGAP_FLAGS mk_vma_flags(VMA_GROWSDOWN_BIT)
#endif
#if defined(CONFIG_PPC64)
#define VM_SAO INIT_VM_FLAG(SAO)
#elif defined(CONFIG_PARISC)
#define VM_GROWSUP INIT_VM_FLAG(GROWSUP)
#define VMA_GROWSUP mk_vma_flags(VMA_GROWSUP_BIT)
#elif defined(CONFIG_SPARC64)
#define VM_SPARC_ADI INIT_VM_FLAG(SPARC_ADI)
#define VM_ARCH_CLEAR INIT_VM_FLAG(ARCH_CLEAR)
#elif defined(CONFIG_ARM64)
#define VM_ARM64_BTI INIT_VM_FLAG(ARM64_BTI)
#define VM_ARCH_CLEAR INIT_VM_FLAG(ARCH_CLEAR)
#elif !defined(CONFIG_MMU)
#define VM_MAPPED_COPY INIT_VM_FLAG(MAPPED_COPY)
#endif
#ifndef VM_GROWSUP
#define VM_GROWSUP VM_NONE
#define VMA_GROWSUP EMPTY_VMA_FLAGS
#endif
#ifdef CONFIG_ARM64_MTE
#define VM_MTE INIT_VM_FLAG(MTE)
#define VM_MTE_ALLOWED INIT_VM_FLAG(MTE_ALLOWED)
#else
#define VM_MTE VM_NONE
#define VM_MTE_ALLOWED VM_NONE
#endif
#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
#define VM_UFFD_MINOR INIT_VM_FLAG(UFFD_MINOR)
#else
#define VM_UFFD_MINOR VM_NONE
#endif
#ifdef CONFIG_USERFAULTFD_RWP
#define VM_UFFD_RWP INIT_VM_FLAG(UFFD_RWP)
#else
#define VM_UFFD_RWP VM_NONE
#endif
/*
* vma_flags_t masks for the userfaultfd VMA flags. The two high-bit modes are
* gated on the same configs as their VM_* flags above -- both of which imply
* 64BIT -- so an out-of-range bit is never fed to mk_vma_flags() on a build
* whose bitmap cannot hold it.
*/
#define VMA_UFFD_MISSING mk_vma_flags(VMA_UFFD_MISSING_BIT)
#define VMA_UFFD_WP mk_vma_flags(VMA_UFFD_WP_BIT)
#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
#define VMA_UFFD_MINOR mk_vma_flags(VMA_UFFD_MINOR_BIT)
#else
#define VMA_UFFD_MINOR EMPTY_VMA_FLAGS
#endif
#ifdef CONFIG_USERFAULTFD_RWP
#define VMA_UFFD_RWP mk_vma_flags(VMA_UFFD_RWP_BIT)
#else
#define VMA_UFFD_RWP EMPTY_VMA_FLAGS
#endif
#ifdef CONFIG_64BIT
#define VM_ALLOW_ANY_UNCACHED INIT_VM_FLAG(ALLOW_ANY_UNCACHED)
#define VM_SEALED INIT_VM_FLAG(SEALED)
#else
#define VM_ALLOW_ANY_UNCACHED VM_NONE
#define VM_SEALED VM_NONE
#endif
#if defined(CONFIG_64BIT) || defined(CONFIG_PPC32)
#define VM_DROPPABLE INIT_VM_FLAG(DROPPABLE)
#define VMA_DROPPABLE mk_vma_flags(VMA_DROPPABLE_BIT)
#else
#define VM_DROPPABLE VM_NONE
#define VMA_DROPPABLE EMPTY_VMA_FLAGS
#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 VMA_STACK_INCOMPLETE_SETUP append_vma_flags( \
VMA_STACK_EARLY, VMA_RAND_READ_BIT, VMA_SEQ_READ_BIT)
#define TASK_EXEC_BIT ((current->personality & READ_IMPLIES_EXEC) ? \
VMA_EXEC_BIT : VMA_READ_BIT)
/* Common data flag combinations */
#define VMA_DATA_FLAGS_TSK_EXEC mk_vma_flags(VMA_READ_BIT, VMA_WRITE_BIT, \
TASK_EXEC_BIT, VMA_MAYREAD_BIT, VMA_MAYWRITE_BIT, \
VMA_MAYEXEC_BIT)
#define VMA_DATA_FLAGS_NON_EXEC mk_vma_flags(VMA_READ_BIT, VMA_WRITE_BIT, \
VMA_MAYREAD_BIT, VMA_MAYWRITE_BIT, VMA_MAYEXEC_BIT)
#define VMA_DATA_FLAGS_EXEC mk_vma_flags(VMA_READ_BIT, VMA_WRITE_BIT, \
VMA_EXEC_BIT, VMA_MAYREAD_BIT, VMA_MAYWRITE_BIT, \
VMA_MAYEXEC_BIT)
#ifndef VMA_DATA_DEFAULT_FLAGS /* arch can override this */
#define VMA_DATA_DEFAULT_FLAGS VMA_DATA_FLAGS_EXEC
#endif
#ifndef VMA_STACK_DEFAULT_FLAGS /* arch can override this */
#define VMA_STACK_DEFAULT_FLAGS VMA_DATA_DEFAULT_FLAGS
#endif
#define VMA_STACK_FLAGS append_vma_flags(VMA_STACK_DEFAULT_FLAGS, \
VMA_STACK_BIT, VMA_ACCOUNT_BIT)
/* Temporary until VMA flags conversion complete. */
#define VM_STACK_FLAGS vma_flags_to_legacy(VMA_STACK_FLAGS)
#ifdef CONFIG_MSEAL_SYSTEM_MAPPINGS
#define VM_SEALED_SYSMAP VM_SEALED
#else
#define VM_SEALED_SYSMAP VM_NONE
#endif
/* VMA basic access permission flags */
#define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC)
#define VMA_ACCESS_FLAGS mk_vma_flags(VMA_READ_BIT, VMA_WRITE_BIT, VMA_EXEC_BIT)
/*
* Special vmas that are non-mergable, non-mlock()able.
*/
#define VMA_SPECIAL_FLAGS mk_vma_flags(VMA_IO_BIT, VMA_DONTEXPAND_BIT, \
VMA_PFNMAP_BIT, VMA_MIXEDMAP_BIT)
#define VM_SPECIAL vma_flags_to_legacy(VMA_SPECIAL_FLAGS)
/*
* Physically remapped pages are special. Tell the
* rest of the world about it:
* IO tells people not to look at these pages
* (accesses can have side effects).
* PFNMAP tells the core MM that the base pages are just
* raw PFN mappings, and do not have a "struct page" associated
* with them.
* DONTEXPAND
* Disable vma merging and expanding with mremap().
* DONTDUMP
* Omit vma from core dump, even when VM_IO turned off.
*/
#define VMA_REMAP_FLAGS mk_vma_flags(VMA_IO_BIT, VMA_PFNMAP_BIT, \
VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT)
/* 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)
#define VMA_LOCKED_MASK mk_vma_flags(VMA_LOCKED_BIT, VMA_LOCKONFAULT_BIT)
/* These flags can be updated atomically via VMA/mmap read lock. */
#define VM_ATOMIC_SET_ALLOWED VM_MAYBE_GUARD
/* 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)
/*
* Flags which should be 'sticky' on merge - that is, flags which, when one VMA
* possesses it but the other does not, the merged VMA should nonetheless have
* applied to it:
*
* VMA_SOFTDIRTY_BIT - if a VMA is marked soft-dirty, that is has not had its
* references cleared via /proc/$pid/clear_refs, any
* merged VMA should be considered soft-dirty also as it
* operates at a VMA granularity.
*
* VMA_MAYBE_GUARD_BIT - If a VMA may have guard regions in place it implies
* that mapped page tables may contain metadata not
* described by the VMA and thus any merged VMA may also
* contain this metadata, and thus we must make this flag
* sticky.
*/
#ifdef CONFIG_MEM_SOFT_DIRTY
#define VMA_STICKY_FLAGS mk_vma_flags(VMA_SOFTDIRTY_BIT, VMA_MAYBE_GUARD_BIT)
#else
#define VMA_STICKY_FLAGS mk_vma_flags(VMA_MAYBE_GUARD_BIT)
#endif
/*
* VMA flags we ignore for the purposes of merge, i.e. one VMA possessing one
* of these flags and the other not does not preclude a merge.
*
* VMA_STICKY_FLAGS - When merging VMAs, VMA flags must match, unless they
* are 'sticky'. If any sticky flags exist in either VMA,
* we simply set all of them on the merged VMA.
*/
#define VMA_IGNORE_MERGE_FLAGS VMA_STICKY_FLAGS
/*
* Flags which should result in page tables being copied on fork. These are
* flags which indicate that the VMA maps page tables which cannot be
* reconsistuted upon page fault, so necessitate page table copying upon fork.
*
* Note that these flags should be compared with the DESTINATION VMA not the
* source: VM_UFFD_WP and VM_UFFD_RWP may be cleared on the destination
* (dup_userfaultfd() -> userfaultfd_reset_ctx() when the parent context did
* not negotiate UFFD_FEATURE_EVENT_FORK), while all other flags propagate.
*
* VM_PFNMAP / VM_MIXEDMAP - These contain kernel-mapped data which cannot be
* reasonably reconstructed on page fault.
*
* VM_UFFD_WP - Encodes metadata about an installed uffd
* VM_UFFD_RWP write- or read-write-protect handler, which
* cannot be reconstructed on page fault.
*
* We always copy pgtables when dst_vma has the
* uffd PTE bit in use even if it's file-backed
* (e.g. shmem). Because when the uffd bit is
* in use, the pgtable contains the protection
* information, that's something we can't
* retrieve from page cache, and skip copying
* will lose those info.
*
* VM_MAYBE_GUARD - Could contain page guard region markers which
* by design are a property of the page tables
* only and thus cannot be reconstructed on page
* fault.
*/
#define VM_COPY_ON_FORK (VM_PFNMAP | VM_MIXEDMAP | VM_UFFD_WP | VM_UFFD_RWP | \
VM_MAYBE_GUARD)
/*
* 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.
*/
};
struct vm_uffd_ops;
/*
* 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 {
/**
* @open: Called when a VMA is remapped, split or forked. Not called
* upon first mapping a VMA.
* Context: User context. May sleep. Caller holds mmap_lock.
*/
void (*open)(struct vm_area_struct *vma);
/**
* @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 *vma);
/**
* @mapped: Called when the VMA is first mapped in the MM. Not called if
* the new VMA is merged with an adjacent VMA.
*
* The @vm_private_data field is an output field allowing the user to
* modify vma->vm_private_data as necessary.
*
* ONLY valid if set from f_op->mmap_prepare. Will result in an error if
* set from f_op->mmap.
*
* Returns %0 on success, or an error otherwise. On error, the VMA will
* be unmapped.
*
* Context: User context. May sleep. Caller holds mmap_lock.
*/
int (*mapped)(unsigned long start, unsigned long end, pgoff_t pgoff,
const struct file *file, void **vm_private_data);
/* Called any time before splitting to check if it's allowed */
int (*may_split)(struct vm_area_struct *vma, unsigned long addr);
int (*mremap)(struct vm_area_struct *vma);
/*
* 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 *vma);
/* 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
#ifdef CONFIG_FIND_NORMAL_PAGE
/*
* Called by vm_normal_page() for special PTEs in @vma at @addr. This
* allows for returning a "normal" page from vm_normal_page() even
* though the PTE indicates that the "struct page" either does not exist
* or should not be touched: "special".
*
* Do not add new users: this really only works when a "normal" page
* was mapped, but then the PTE got changed to something weird (+
* marked special) that would not make pte_pfn() identify the originally
* inserted page.
*/
struct page *(*find_normal_page)(struct vm_area_struct *vma,
unsigned long addr);
#endif /* CONFIG_FIND_NORMAL_PAGE */
#ifdef CONFIG_USERFAULTFD
const struct vm_uffd_ops *uffd_ops;
#endif
};
#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 */
/*
* These must be here rather than mmap_lock.h as dependent on vm_fault type,
* declared in this header.
*/
#ifdef CONFIG_PER_VMA_LOCK
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(const struct vm_fault *vmf)
{
if (vmf->flags & FAULT_FLAG_VMA_LOCK)
vma_assert_locked(vmf->vma);
else
mmap_assert_locked(vmf->vma->vm_mm);
}
#else
static inline void release_fault_lock(struct vm_fault *vmf)
{
mmap_read_unlock(vmf->vma->vm_mm);
}
static inline void assert_fault_locked(const struct vm_fault *vmf)
{
mmap_assert_locked(vmf->vma->vm_mm);
}
#endif /* CONFIG_PER_VMA_LOCK */
static inline bool mm_flags_test(int flag, const struct mm_struct *mm)
{
return test_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags));
}
static inline bool mm_flags_test_and_set(int flag, struct mm_struct *mm)
{
return test_and_set_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags));
}
static inline bool mm_flags_test_and_clear(int flag, struct mm_struct *mm)
{
return test_and_clear_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags));
}
static inline void mm_flags_set(int flag, struct mm_struct *mm)
{
set_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags));
}
static inline void mm_flags_clear(int flag, struct mm_struct *mm)
{
clear_bit(flag, ACCESS_PRIVATE(&mm->flags, __mm_flags));
}
static inline void mm_flags_clear_all(struct mm_struct *mm)
{
bitmap_zero(ACCESS_PRIVATE(&mm->flags, __mm_flags), NUM_MM_FLAG_BITS);
}
extern const struct vm_operations_struct vma_dummy_vm_ops;
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_lock_init(vma, false);
}
/* Use when VMA is not part of the VMA tree and needs no locking */
static inline void vm_flags_init(struct vm_area_struct *vma,
vm_flags_t flags)
{
VM_WARN_ON_ONCE(!pgtable_supports_soft_dirty() && (flags & VM_SOFTDIRTY));
vma_flags_clear_all(&vma->flags);
vma_flags_overwrite_word(&vma->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)
{
VM_WARN_ON_ONCE(!pgtable_supports_soft_dirty() && (flags & VM_SOFTDIRTY));
vma_assert_write_locked(vma);
vm_flags_init(vma, flags);
}
static inline void vma_flags_reset_once(struct vm_area_struct *vma,
vma_flags_t *flags)
{
const unsigned long word = flags->__vma_flags[0];
/* It is assumed only the first system word must be written once. */
vma_flags_overwrite_word_once(&vma->flags, word);
/* The remainder can be copied normally. */
if (NUM_VMA_FLAG_BITS > BITS_PER_LONG) {
unsigned long *dst = &vma->flags.__vma_flags[1];
const unsigned long *src = &flags->__vma_flags[1];
bitmap_copy(dst, src, NUM_VMA_FLAG_BITS - BITS_PER_LONG);
}
}
static inline void vm_flags_set(struct vm_area_struct *vma,
vm_flags_t flags)
{
vma_start_write(vma);
vma_flags_set_word(&vma->flags, flags);
}
static inline void vm_flags_clear(struct vm_area_struct *vma,
vm_flags_t flags)
{
VM_WARN_ON_ONCE(!pgtable_supports_soft_dirty() && (flags & VM_SOFTDIRTY));
vma_start_write(vma);
vma_flags_clear_word(&vma->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 __always_inline bool __vma_atomic_valid_flag(struct vm_area_struct *vma,
vma_flag_t bit)
{
const vm_flags_t mask = BIT((__force int)bit);
/* Only specific flags are permitted */
if (WARN_ON_ONCE(!(mask & VM_ATOMIC_SET_ALLOWED)))
return false;
return true;
}
/*
* Set VMA flag atomically. Requires only VMA/mmap read lock. Only specific
* valid flags are allowed to do this.
*/
static __always_inline void vma_set_atomic_flag(struct vm_area_struct *vma,
vma_flag_t bit)
{
unsigned long *bitmap = vma->flags.__vma_flags;
vma_assert_stabilised(vma);
if (__vma_atomic_valid_flag(vma, bit))
set_bit((__force int)bit, bitmap);
}
/*
* Test for VMA flag atomically. Requires no locks. Only specific valid flags
* are allowed to do this.
*
* This is necessarily racey, so callers must ensure that serialisation is
* achieved through some other means, or that races are permissible.
*/
static __always_inline bool vma_test_atomic_flag(struct vm_area_struct *vma,
vma_flag_t bit)
{
if (__vma_atomic_valid_flag(vma, bit))
return test_bit((__force int)bit, &vma->vm_flags);
return false;
}
/* Set an individual VMA flag in flags, non-atomically. */
static __always_inline void vma_flags_set_flag(vma_flags_t *flags,
vma_flag_t bit)
{
unsigned long *bitmap = flags->__vma_flags;
__set_bit((__force int)bit, bitmap);
}
static __always_inline vma_flags_t __mk_vma_flags(vma_flags_t flags,
size_t count, const vma_flag_t *bits)
{
int i;
for (i = 0; i < count; i++)
vma_flags_set_flag(&flags, bits[i]);
return flags;
}
/*
* Helper macro which bitwise-or combines the specified input flags into a
* vma_flags_t bitmap value. E.g.:
*
* vma_flags_t flags = mk_vma_flags(VMA_IO_BIT, VMA_PFNMAP_BIT,
* VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT);
*
* The compiler cleverly optimises away all of the work and this ends up being
* equivalent to aggregating the values manually.
*/
#define mk_vma_flags(...) __mk_vma_flags(EMPTY_VMA_FLAGS, \
COUNT_ARGS(__VA_ARGS__), (const vma_flag_t []){__VA_ARGS__})
/*
* Helper macro which acts like mk_vma_flags, only appending to a copy of the
* specified flags rather than establishing new flags. E.g.:
*
* vma_flags_t flags = append_vma_flags(VMA_STACK_DEFAULT_FLAGS, VMA_STACK_BIT,
* VMA_ACCOUNT_BIT);
*/
#define append_vma_flags(flags, ...) __mk_vma_flags(flags, \
COUNT_ARGS(__VA_ARGS__), (const vma_flag_t []){__VA_ARGS__})
/* Calculates the number of set bits in the specified VMA flags. */
static __always_inline int vma_flags_count(const vma_flags_t *flags)
{
const unsigned long *bitmap = flags->__vma_flags;
return bitmap_weight(bitmap, NUM_VMA_FLAG_BITS);
}
/*
* Test whether a specific VMA flag is set, e.g.:
*
* if (vma_flags_test(flags, VMA_READ_BIT)) { ... }
*/
static __always_inline bool vma_flags_test(const vma_flags_t *flags,
vma_flag_t bit)
{
const unsigned long *bitmap = flags->__vma_flags;
return test_bit((__force int)bit, bitmap);
}
/*
* Obtain a set of VMA flags which contain the overlapping flags contained
* within flags and to_and.
*/
static __always_inline vma_flags_t vma_flags_and_mask(const vma_flags_t *flags,
vma_flags_t to_and)
{
vma_flags_t dst;
unsigned long *bitmap_dst = dst.__vma_flags;
const unsigned long *bitmap = flags->__vma_flags;
const unsigned long *bitmap_to_and = to_and.__vma_flags;
bitmap_and(bitmap_dst, bitmap, bitmap_to_and, NUM_VMA_FLAG_BITS);
return dst;
}
/*
* Obtain a set of VMA flags which contains the specified overlapping flags,
* e.g.:
*
* vma_flags_t read_flags = vma_flags_and(&flags, VMA_READ_BIT,
* VMA_MAY_READ_BIT);
*/
#define vma_flags_and(flags, ...) \
vma_flags_and_mask(flags, mk_vma_flags(__VA_ARGS__))
/* Test each of to_test flags in flags, non-atomically. */
static __always_inline bool vma_flags_test_any_mask(const vma_flags_t *flags,
vma_flags_t to_test)
{
const unsigned long *bitmap = flags->__vma_flags;
const unsigned long *bitmap_to_test = to_test.__vma_flags;
return bitmap_intersects(bitmap_to_test, bitmap, NUM_VMA_FLAG_BITS);
}
/*
* Test whether any specified VMA flag is set, e.g.:
*
* if (vma_flags_test_any(flags, VMA_READ_BIT, VMA_MAYREAD_BIT)) { ... }
*/
#define vma_flags_test_any(flags, ...) \
vma_flags_test_any_mask(flags, mk_vma_flags(__VA_ARGS__))
/* Test that ALL of the to_test flags are set, non-atomically. */
static __always_inline bool vma_flags_test_all_mask(const vma_flags_t *flags,
vma_flags_t to_test)
{
const unsigned long *bitmap = flags->__vma_flags;
const unsigned long *bitmap_to_test = to_test.__vma_flags;
return bitmap_subset(bitmap_to_test, bitmap, NUM_VMA_FLAG_BITS);
}
/*
* Test whether ALL specified VMA flags are set, e.g.:
*
* if (vma_flags_test_all(flags, VMA_READ_BIT, VMA_MAYREAD_BIT)) { ... }
*/
#define vma_flags_test_all(flags, ...) \
vma_flags_test_all_mask(flags, mk_vma_flags(__VA_ARGS__))
/*
* Helper to test that a flag mask of type vma_flags_t has a SINGLE flag set
* (returning false if flagmask has no flags set).
*
* This is defined to make the semantics clearer when testing an optionally
* defined VMA flags mask, e.g.:
*
* if (vma_flags_test_single_mask(&flags, VMA_DROPPABLE)) { ... }
*
* When VMA_DROPPABLE is defined if available, or set to EMPTY_VMA_FLAGS
* otherwise.
*/
static __always_inline bool vma_flags_test_single_mask(const vma_flags_t *flags,
vma_flags_t flagmask)
{
VM_WARN_ON_ONCE(vma_flags_count(&flagmask) > 1);
return vma_flags_test_any_mask(flags, flagmask);
}
/* Set each of the to_set flags in flags, non-atomically. */
static __always_inline void vma_flags_set_mask(vma_flags_t *flags,
vma_flags_t to_set)
{
unsigned long *bitmap = flags->__vma_flags;
const unsigned long *bitmap_to_set = to_set.__vma_flags;
bitmap_or(bitmap, bitmap, bitmap_to_set, NUM_VMA_FLAG_BITS);
}
/*
* Set all specified VMA flags, e.g.:
*
* vma_flags_set(&flags, VMA_READ_BIT, VMA_WRITE_BIT, VMA_EXEC_BIT);
*/
#define vma_flags_set(flags, ...) \
vma_flags_set_mask(flags, mk_vma_flags(__VA_ARGS__))
static __always_inline vma_flags_t __mk_vma_flags_from_masks(size_t count,
const vma_flags_t *masks)
{
vma_flags_t flags = EMPTY_VMA_FLAGS;
size_t i;
for (i = 0; i < count; i++)
vma_flags_set_mask(&flags, masks[i]);
return flags;
}
/*
* Combine pre-computed vma_flags_t masks into one value, e.g.:
*
* vma_flags_t flags = mk_vma_flags_from_masks(VMA_UFFD_WP, VMA_UFFD_MINOR);
*
* Unlike mk_vma_flags(), which takes bit numbers, this takes whole masks --
* each of which may be EMPTY_VMA_FLAGS when its feature is unavailable -- so a
* bit that does not exist on the current build is never materialised.
*/
#define mk_vma_flags_from_masks(...) \
__mk_vma_flags_from_masks(COUNT_ARGS(__VA_ARGS__), \
(const vma_flags_t []){__VA_ARGS__})
/* Clear all of the to-clear flags in flags, non-atomically. */
static __always_inline void vma_flags_clear_mask(vma_flags_t *flags,
vma_flags_t to_clear)
{
unsigned long *bitmap = flags->__vma_flags;
const unsigned long *bitmap_to_clear = to_clear.__vma_flags;
bitmap_andnot(bitmap, bitmap, bitmap_to_clear, NUM_VMA_FLAG_BITS);
}
/*
* Clear all specified individual flags, e.g.:
*
* vma_flags_clear(&flags, VMA_READ_BIT, VMA_WRITE_BIT, VMA_EXEC_BIT);
*/
#define vma_flags_clear(flags, ...) \
vma_flags_clear_mask(flags, mk_vma_flags(__VA_ARGS__))
/*
* Obtain a VMA flags value containing those flags that are present in flags or
* flags_other but not in both.
*/
static __always_inline vma_flags_t vma_flags_diff_pair(const vma_flags_t *flags,
const vma_flags_t *flags_other)
{
vma_flags_t dst;
const unsigned long *bitmap_other = flags_other->__vma_flags;
const unsigned long *bitmap = flags->__vma_flags;
unsigned long *bitmap_dst = dst.__vma_flags;
bitmap_xor(bitmap_dst, bitmap, bitmap_other, NUM_VMA_FLAG_BITS);
return dst;
}
/* Determine if flags and flags_other have precisely the same flags set. */
static __always_inline bool vma_flags_same_pair(const vma_flags_t *flags,
const vma_flags_t *flags_other)
{
const unsigned long *bitmap = flags->__vma_flags;
const unsigned long *bitmap_other = flags_other->__vma_flags;
return bitmap_equal(bitmap, bitmap_other, NUM_VMA_FLAG_BITS);
}
/* Determine if flags and flags_other have precisely the same flags set. */
static __always_inline bool vma_flags_same_mask(const vma_flags_t *flags,
vma_flags_t flags_other)
{
const unsigned long *bitmap = flags->__vma_flags;
const unsigned long *bitmap_other = flags_other.__vma_flags;
return bitmap_equal(bitmap, bitmap_other, NUM_VMA_FLAG_BITS);
}
/*
* Helper macro to determine if only the specific flags are set, e.g.:
*
* if (vma_flags_same(&flags, VMA_WRITE_BIT) { ... }
*/
#define vma_flags_same(flags, ...) \
vma_flags_same_mask(flags, mk_vma_flags(__VA_ARGS__))
/*
* Test whether a specific flag in the VMA is set, e.g.:
*
* if (vma_test(vma, VMA_READ_BIT)) { ... }
*/
static __always_inline bool vma_test(const struct vm_area_struct *vma,
vma_flag_t bit)
{
return vma_flags_test(&vma->flags, bit);
}
/* Helper to test any VMA flags in a VMA . */
static __always_inline bool vma_test_any_mask(const struct vm_area_struct *vma,
vma_flags_t flags)
{
return vma_flags_test_any_mask(&vma->flags, flags);
}
/*
* Helper macro for testing whether any VMA flags are set in a VMA,
* e.g.:
*
* if (vma_test_any(vma, VMA_IO_BIT, VMA_PFNMAP_BIT,
* VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT)) { ... }
*/
#define vma_test_any(vma, ...) \
vma_test_any_mask(vma, mk_vma_flags(__VA_ARGS__))
/*
* Helper to test that ALL specified flags are set in a VMA.
*
* Note: appropriate locks must be held, this function does not acquire them for
* you.
*/
static __always_inline bool vma_test_all_mask(const struct vm_area_struct *vma,
vma_flags_t flags)
{
return vma_flags_test_all_mask(&vma->flags, flags);
}
/*
* Helper macro for checking that ALL specified flags are set in a VMA, e.g.:
*
* if (vma_test_all(vma, VMA_READ_BIT, VMA_MAYREAD_BIT) { ... }
*/
#define vma_test_all(vma, ...) \
vma_test_all_mask(vma, mk_vma_flags(__VA_ARGS__))
/*
* Helper to test that a flag mask of type vma_flags_t has a SINGLE flag set
* (returning false if flagmask has no flags set).
*
* This is useful when a flag needs to be either defined or not depending upon
* kernel configuration, e.g.:
*
* if (vma_test_single_mask(vma, VMA_DROPPABLE)) { ... }
*
* When VMA_DROPPABLE is defined if available, or set to EMPTY_VMA_FLAGS
* otherwise.
*/
static __always_inline bool
vma_test_single_mask(const struct vm_area_struct *vma, vma_flags_t flagmask)
{
return vma_flags_test_single_mask(&vma->flags, flagmask);
}
/*
* Helper to set all VMA flags in a VMA.
*
* Note: appropriate locks must be held, this function does not acquire them for
* you.
*/
static __always_inline void vma_set_flags_mask(struct vm_area_struct *vma,
vma_flags_t flags)
{
vma_flags_set_mask(&vma->flags, flags);
}
/*
* Helper macro for specifying VMA flags in a VMA, e.g.:
*
* vma_set_flags(vma, VMA_IO_BIT, VMA_PFNMAP_BIT, VMA_DONTEXPAND_BIT,
* VMA_DONTDUMP_BIT);
*
* Note: appropriate locks must be held, this function does not acquire them for
* you.
*/
#define vma_set_flags(vma, ...) \
vma_set_flags_mask(vma, mk_vma_flags(__VA_ARGS__))
/* Helper to clear all VMA flags in a VMA. */
static __always_inline void vma_clear_flags_mask(struct vm_area_struct *vma,
vma_flags_t flags)
{
vma_flags_clear_mask(&vma->flags, flags);
}
/*
* Helper macro for clearing VMA flags, e.g.:
*
* vma_clear_flags(vma, VMA_IO_BIT, VMA_PFNMAP_BIT, VMA_DONTEXPAND_BIT,
* VMA_DONTDUMP_BIT);
*/
#define vma_clear_flags(vma, ...) \
vma_clear_flags_mask(vma, mk_vma_flags(__VA_ARGS__))
/*
* Test whether a specific VMA flag is set in a VMA descriptor, e.g.:
*
* if (vma_desc_test(desc, VMA_READ_BIT)) { ... }
*/
static __always_inline bool vma_desc_test(const struct vm_area_desc *desc,
vma_flag_t bit)
{
return vma_flags_test(&desc->vma_flags, bit);
}
/* Helper to test any VMA flags in a VMA descriptor. */
static __always_inline bool vma_desc_test_any_mask(const struct vm_area_desc *desc,
vma_flags_t flags)
{
return vma_flags_test_any_mask(&desc->vma_flags, flags);
}
/*
* Helper macro for testing whether any VMA flags are set in a VMA descriptor,
* e.g.:
*
* if (vma_desc_test_any(desc, VMA_IO_BIT, VMA_PFNMAP_BIT,
* VMA_DONTEXPAND_BIT, VMA_DONTDUMP_BIT)) { ... }
*/
#define vma_desc_test_any(desc, ...) \
vma_desc_test_any_mask(desc, mk_vma_flags(__VA_ARGS__))
/* Helper to test all VMA flags in a VMA descriptor. */
static __always_inline bool vma_desc_test_all_mask(const struct vm_area_desc *desc,
vma_flags_t flags)
{
return vma_flags_test_all_mask(&desc->vma_flags, flags);
}
/*
* Helper macro for testing whether ALL VMA flags are set in a VMA descriptor,
* e.g.:
*
* if (vma_desc_test_all(desc, VMA_READ_BIT, VMA_MAYREAD_BIT)) { ... }
*/
#define vma_desc_test_all(desc, ...) \
vma_desc_test_all_mask(desc, mk_vma_flags(__VA_ARGS__))
/* Helper to set all VMA flags in a VMA descriptor. */
static __always_inline void vma_desc_set_flags_mask(struct vm_area_desc *desc,
vma_flags_t flags)
{
vma_flags_set_mask(&desc->vma_flags, flags);
}
/*
* Helper macro for specifying VMA flags for an input pointer to a struct
* vm_area_desc object describing a proposed VMA, e.g.:
*
* vma_desc_set_flags(desc, VMA_IO_BIT, VMA_PFNMAP_BIT, VMA_DONTEXPAND_BIT,
* VMA_DONTDUMP_BIT);
*/
#define vma_desc_set_flags(desc, ...) \
vma_desc_set_flags_mask(desc, mk_vma_flags(__VA_ARGS__))
/* Helper to clear all VMA flags in a VMA descriptor. */
static __always_inline void vma_desc_clear_flags_mask(struct vm_area_desc *desc,
vma_flags_t flags)
{
vma_flags_clear_mask(&desc->vma_flags, flags);
}
/*
* Helper macro for clearing VMA flags for an input pointer to a struct
* vm_area_desc object describing a proposed VMA, e.g.:
*
* vma_desc_clear_flags(desc, VMA_IO_BIT, VMA_PFNMAP_BIT, VMA_DONTEXPAND_BIT,
* VMA_DONTDUMP_BIT);
*/
#define vma_desc_clear_flags(desc, ...) \
vma_desc_clear_flags_mask(desc, mk_vma_flags(__VA_ARGS__))
static inline void vma_set_anonymous(struct vm_area_struct *vma)
{
vma->vm_ops = NULL;
}
static inline void vma_desc_set_anonymous(struct vm_area_desc *desc)
{
desc->vm_ops = NULL;
}
static inline bool vma_is_anonymous(const 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_flags_can_grow(const vma_flags_t *flags)
{
if (vma_flags_test_single_mask(flags, VMA_GROWSUP))
return true;
if (vma_flags_test(flags, VMA_GROWSDOWN_BIT))
return true;
return false;
}
static inline bool vma_can_grow(const struct vm_area_struct *vma)
{
return vma_flags_can_grow(&vma->flags);
}
static inline bool vma_is_temporary_stack(const struct vm_area_struct *vma)
{
if (!vma_can_grow(vma))
return false;
if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) ==
VM_STACK_INCOMPLETE_SETUP)
return true;
return false;
}
static inline bool vma_is_foreign(const 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(const struct vm_area_struct *vma)
{
return vma->vm_flags & VM_ACCESS_FLAGS;
}
static inline bool is_shared_maywrite(const vma_flags_t *flags)
{
return vma_flags_test_all(flags, VMA_SHARED_BIT, VMA_MAYWRITE_BIT);
}
static inline bool vma_is_shared_maywrite(const struct vm_area_struct *vma)
{
return is_shared_maywrite(&vma->flags);
}
/**
* vma_kernel_pagesize - Default page size granularity for this VMA.
* @vma: The user mapping.
*
* The kernel page size specifies in which granularity VMA modifications
* can be performed. Folios in this VMA will be aligned to, and at least
* the size of the number of bytes returned by this function.
*
* The default kernel page size is not affected by Transparent Huge Pages
* being in effect.
*
* Return: The default page size granularity for this VMA.
*/
static inline unsigned long vma_kernel_pagesize(struct vm_area_struct *vma)
{
if (unlikely(vma->vm_ops && vma->vm_ops->pagesize))
return vma->vm_ops->pagesize(vma);
return PAGE_SIZE;
}
unsigned long vma_mmu_pagesize(struct vm_area_struct *vma);
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;
vma_mark_attached(vma);
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(const struct vm_area_struct *vma);
bool vma_is_anon_shmem(const struct vm_area_struct *vma);
#else
static inline bool vma_is_shmem(const struct vm_area_struct *vma) { return false; }
static inline bool vma_is_anon_shmem(const struct vm_area_struct *vma) { return false; }
#endif
int vma_is_stack_for_current(const 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;
extern void prep_compound_page(struct page *page, unsigned int order);
static inline unsigned int folio_large_order(const struct folio *folio)
{
return folio->_flags_1 & 0xff;
}
#ifdef NR_PAGES_IN_LARGE_FOLIO
static inline unsigned long folio_large_nr_pages(const struct folio *folio)
{
return folio->_nr_pages;
}
#else
static inline unsigned long folio_large_nr_pages(const struct folio *folio)
{
return 1L << folio_large_order(folio);
}
#endif
/*
* 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(const struct page *page)
{
const struct folio *folio = (struct folio *)page;
if (!test_bit(PG_head, &folio->flags.f))
return 0;
return folio_large_order(folio);
}
/**
* 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_large_order(folio);
}
/**
* folio_reset_order - Reset the folio order and derived _nr_pages
* @folio: The folio.
*
* Reset the order and derived _nr_pages to 0. Must only be used in the
* process of splitting large folios.
*/
static inline void folio_reset_order(struct folio *folio)
{
if (WARN_ON_ONCE(!folio_test_large(folio)))
return;
folio->_flags_1 &= ~0xffUL;
#ifdef NR_PAGES_IN_LARGE_FOLIO
folio->_nr_pages = 0;
#endif
}
#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_zero(page, 1);
}
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);
if (!IS_ENABLED(CONFIG_64BIT) && unlikely(folio_large_order(folio) == 1))
return 0;
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;
}
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 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(const 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 folio *folio, 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 folio may belong to an inode's memory mapping. In this case,
* folio->mapping points to the inode, and folio->index is the file
* offset of the folio, 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.
*/
/* 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)
{
struct folio *folio = page_folio(page);
if (WARN_ON_ONCE(folio_test_slab(folio)))
return;
if (WARN_ON_ONCE(folio_test_large_kmalloc(folio)))
return;
folio_get(folio);
}
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);
if (folio_test_slab(folio) || folio_test_large_kmalloc(folio))
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);
/**
* vma_flags_is_cow_mapping() - Do these VMA flags imply a CoW mapping?
* @flags: The VMA flags to check.
*
* Mappings which could be CoW'd (subject to Copy-On-Write faults) are
* described as CoW mappings.
*
* All mappings backed by anonymous folios (all anonymous mappings and most
* MAP_PRIVATE-file backed ranges) are CoW mappings.
*
* All other mappings (including all MAP_SHARED mappings) are non-CoW.
*
* The criteria are !VMA_SHARED_BIT, VMA_MAYWRITE_BIT.
*
* VMA_MAYWRITE_BIT is checked instead of VMA_WRITE_BIT to account for both
* future mprotect() calls which can render a read-only mapping writable, and
* GUP with FOLL_FORCE (e.g. ptrace) which can CoW a read-only mapping.
*
* - No anonymous mapping can ever clear VMA_MAYWRITE_BIT.
*
* - Writes to anonymous mappings do not immediately result in CoW faults but
* may do so after the process is forked or if a read is followed by a
* write.
*
* - Writes to MAP_PRIVATE file-backed mappings result in CoW faults and may
* do so again after fork.
*
* - MAP_SHARED mappings of a file opened read-only are transformed into
* VMA_MAYSHARE_BIT, !VMA_SHARED_BIT, !VMA_MAYWRITE_BIT mappings, so remain
* non-CoW.
*
* - Drivers may clear VMA_MAYWRITE_BIT but do so at mmap() time and cannot
* mark themselves anonymous. Having cleared this flag it is not valid for
* them to leave the VMA_WRITE_BIT flag set.
*
* As a consequence, the anonymous reverse mapping only tracks CoW mappings.
*
* Returns: true if the flags indicate a CoW mapping, otherwise false.
*/
static inline bool vma_flags_is_cow_mapping(const vma_flags_t *flags)
{
return vma_flags_test(flags, VMA_MAYWRITE_BIT) &&
!vma_flags_test(flags, VMA_SHARED_BIT);
}
/**
* vma_is_cow_mapping() - Is this VMA a CoW mapping?
* @vma: The VMA to check.
*
* See vma_flags_is_cow_mapping() for details.
*
* Returns: true if the VMA is a CoW mapping, otherwise false.
*/
static inline bool vma_is_cow_mapping(const struct vm_area_struct *vma)
{
return vma_flags_is_cow_mapping(&vma->flags);
}
/**
* vma_desc_is_cow_mapping() - Is this VMA descriptor a CoW mapping?
* @desc: The VMA descriptor to check.
*
* See vma_flags_is_cow_mapping() for details.
*
* Returns: true if the VMA descriptor describes a CoW mapping, otherwise
* false.
*/
static inline bool vma_desc_is_cow_mapping(struct vm_area_desc *desc)
{
return vma_flags_is_cow_mapping(&desc->vma_flags);
}
#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);
}
static inline bool is_nommu_shared_vma_flags(const vma_flags_t *flags)
{
return vma_flags_test_any(flags, VMA_MAYSHARE_BIT, VMA_MAYOVERLAY_BIT);
}
#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.f >> ZONEID_PGSHIFT) & ZONEID_MASK;
}
#ifdef NODE_NOT_IN_PAGE_FLAGS
int memdesc_nid(const memdesc_flags_t *mdf);
#else
#ifdef CONFIG_NUMA
static inline int memdesc_nid(const memdesc_flags_t *mdf)
{
ASSERT_EXCLUSIVE_BITS(mdf->f, NODES_MASK << NODES_PGSHIFT);
return (mdf->f >> NODES_PGSHIFT) & NODES_MASK;
}
#else
static inline int memdesc_nid(const memdesc_flags_t *mdf)
{
return 0;
}
#endif
#endif
static inline int page_to_nid(const struct page *page)
{
return memdesc_nid(&(PF_POISONED_CHECK(page)->flags));
}
static inline int folio_nid(const struct folio *folio)
{
return memdesc_nid(&folio->flags);
}
#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.f >> 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.f |= 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.f >> 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.f);
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.f, &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 pg_data_t *folio_pgdat(const struct folio *folio)
{
return NODE_DATA(folio_nid(folio));
}
static inline struct zone *folio_zone(const struct folio *folio)
{
return &folio_pgdat(folio)->node_zones[folio_zonenum(folio)];
}
#ifdef SECTION_IN_PAGE_FLAGS
static inline void set_page_section(struct page *page, unsigned long section)
{
page->flags.f &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
page->flags.f |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
}
static inline unsigned long memdesc_section(const memdesc_flags_t *mdf)
{
ASSERT_EXCLUSIVE_BITS(mdf->f, SECTIONS_MASK << SECTIONS_PGSHIFT);
return (mdf->f >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
}
#else /* !SECTION_IN_PAGE_FLAGS */
static inline unsigned long memdesc_section(const memdesc_flags_t *mdf)
{
return 0;
}
#endif /* SECTION_IN_PAGE_FLAGS */
/**
* 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(const 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));
}
#ifdef CONFIG_MMU
static inline pte_t mk_pte(const struct page *page, pgprot_t pgprot)
{
return pfn_pte(page_to_pfn(page), pgprot);
}
/**
* folio_mk_pte - Create a PTE for this folio
* @folio: The folio to create a PTE for
* @pgprot: The page protection bits to use
*
* Create a page table entry for the first page of this folio.
* This is suitable for passing to set_ptes().
*
* Return: A page table entry suitable for mapping this folio.
*/
static inline pte_t folio_mk_pte(const struct folio *folio, pgprot_t pgprot)
{
return pfn_pte(folio_pfn(folio), pgprot);
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
/**
* folio_mk_pmd - Create a PMD for this folio
* @folio: The folio to create a PMD for
* @pgprot: The page protection bits to use
*
* Create a page table entry for the first page of this folio.
* This is suitable for passing to set_pmd_at().
*
* Return: A page table entry suitable for mapping this folio.
*/
static inline pmd_t folio_mk_pmd(const struct folio *folio, pgprot_t pgprot)
{
return pmd_mkhuge(pfn_pmd(folio_pfn(folio), pgprot));
}
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
/**
* folio_mk_pud - Create a PUD for this folio
* @folio: The folio to create a PUD for
* @pgprot: The page protection bits to use
*
* Create a page table entry for the first page of this folio.
* This is suitable for passing to set_pud_at().
*
* Return: A page table entry suitable for mapping this folio.
*/
static inline pud_t folio_mk_pud(const struct folio *folio, pgprot_t pgprot)
{
return pud_mkhuge(pfn_pud(folio_pfn(folio), pgprot));
}
#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
#endif /* CONFIG_MMU */
static inline bool folio_has_pincount(const struct folio *folio)
{
if (IS_ENABLED(CONFIG_64BIT))
return folio_test_large(folio);
return folio_order(folio) > 1;
}
/**
* 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 most 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_has_pincount(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 (!mm_flags_test(MMF_HAS_PINNED, vma->vm_mm))
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;
/*
* Filesystems can only tolerate transient delays to truncate and
* hole-punch operations
*/
if (folio_is_fsdax(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.f &= ~(ZONES_MASK << ZONES_PGSHIFT);
page->flags.f |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
}
static inline void set_page_node(struct page *page, unsigned long node)
{
page->flags.f &= ~(NODES_MASK << NODES_PGSHIFT);
page->flags.f |= (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 unsigned long folio_nr_pages(const struct folio *folio)
{
if (!folio_test_large(folio))
return 1;
return folio_large_nr_pages(folio);
}
/*
* 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(const struct page *page)
{
const struct folio *folio = (struct folio *)page;
if (!test_bit(PG_head, &folio->flags.f))
return 1;
return folio_large_nr_pages(folio);
}
/**
* 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_maybe_mapped_shared - Whether the folio is mapped into the page
* tables of more than one MM
* @folio: The folio.
*
* This function checks if the folio maybe currently mapped into more than one
* MM ("maybe mapped shared"), or if the folio is certainly 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.
*
* 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 shared" (false positive) if a folio was mapped by
* more than two MMs at one point in time.
* #. 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_maybe_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;
/*
* vm_insert_page() without CONFIG_TRANSPARENT_HUGEPAGE ...
* simply assume "mapped shared", nobody should really care
* about this for arbitrary kernel allocations.
*/
if (!IS_ENABLED(CONFIG_MM_ID))
return true;
/*
* A single mapping implies "mapped exclusively", even if the
* folio flag says something different: it's easier to handle this
* case here instead of on the RMAP hot path.
*/
if (mapcount <= 1)
return false;
return test_bit(FOLIO_MM_IDS_SHARED_BITNUM, &folio->_mm_ids);
}
/**
* folio_expected_ref_count - calculate the expected folio refcount
* @folio: the folio
*
* Calculate the expected folio refcount, taking references from the pagecache,
* swapcache, PG_private and page table mappings into account. Useful in
* combination with folio_ref_count() to detect unexpected references (e.g.,
* GUP or other temporary references).
*
* Does currently not consider references from the LRU cache. If the folio
* was isolated from the LRU (which is the case during migration or split),
* the LRU cache does not apply.
*
* Calling this function on an unmapped folio -- !folio_mapped() -- that is
* locked will return a stable result.
*
* Calling this function on a mapped folio will not result in a stable result,
* because nothing stops additional page table mappings from coming (e.g.,
* fork()) or going (e.g., munmap()).
*
* Calling this function without the folio lock will also not result in a
* stable result: for example, the folio might get dropped from the swapcache
* concurrently.
*
* However, even when called without the folio lock or on a mapped folio,
* this function can be used to detect unexpected references early (for example,
* if it makes sense to even lock the folio and unmap it).
*
* The caller must add any reference (e.g., from folio_try_get()) it might be
* holding itself to the result.
*
* Returns: the expected folio refcount.
*/
static inline int folio_expected_ref_count(const struct folio *folio)
{
const int order = folio_order(folio);
int ref_count = 0;
if (WARN_ON_ONCE(page_has_type(&folio->page) && !folio_test_hugetlb(folio)))
return 0;
/* One reference per page from the swapcache. */
ref_count += folio_test_swapcache(folio) << order;
if (!folio_test_anon(folio)) {
/* One reference per page from the pagecache. */
ref_count += !!folio->mapping << order;
/* One reference from PG_private. */
ref_count += folio_test_private(folio);
}
/* One reference per page table mapping. */
return ref_count + folio_mapcount(folio);
}
#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_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 skip_cows; /* Do not zap COWed private pages */
bool reclaim_pt; /* Need reclaim page tables? */
bool reaping; /* Reaping, do not block. */
zap_flags_t zap_flags; /* Extra flags for zapping */
};
/*
* Whether to drop the pte markers, for example, the uffd-wp information for
* file-backed memory. This should only be specified when we will completely
* drop the page in the mm, either by truncation or unmapping of the vma. By
* default, the flag is not set.
*/
#define ZAP_FLAG_DROP_MARKER ((__force zap_flags_t) BIT(0))
/* Set in unmap_vmas() to indicate a final unmap call. Only used by hugetlb */
#define ZAP_FLAG_UNMAP ((__force zap_flags_t) BIT(1))
#ifdef CONFIG_MMU
extern bool can_do_mlock(void);
#else
static inline bool can_do_mlock(void) { return false; }
#endif
extern int user_shm_lock(size_t, struct ucounts *);
extern void user_shm_unlock(size_t, struct ucounts *);
struct folio *vm_normal_folio(struct vm_area_struct *vma, unsigned long addr,
pte_t pte);
struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
pte_t pte);
struct 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);
struct page *vm_normal_page_pud(struct vm_area_struct *vma, unsigned long addr,
pud_t pud);
void zap_special_vma_range(struct vm_area_struct *vma, unsigned long address,
unsigned long size);
void zap_vma_range(struct vm_area_struct *vma, unsigned long address,
unsigned long size);
/**
* zap_vma - zap all page table entries in a vma
* @vma: The vma to zap.
*/
static inline void zap_vma(struct vm_area_struct *vma)
{
zap_vma_range(vma, vma->vm_start, vma->vm_end - vma->vm_start);
}
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
* @addr_mask: address mask covering pfn
* @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;
unsigned long addr_mask;
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);
#ifdef CONFIG_BPF_SYSCALL
extern int copy_remote_vm_str(struct task_struct *tsk, unsigned long addr,
void *buf, int len, unsigned int gup_flags);
#endif
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 folio_add_pins(struct folio *folio, unsigned int pins);
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,
const struct task_struct *task, bool bypass_rlim);
struct kvec;
struct page *get_dump_page(unsigned long addr, int *locked);
bool folio_mark_dirty(struct folio *folio);
bool folio_mark_dirty_lock(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)
/* Whether this change is for uffd RWP */
#define MM_CP_UFFD_RWP (1UL << 4) /* do rwp */
#define MM_CP_UFFD_RWP_RESOLVE (1UL << 5) /* resolve rwp */
#define MM_CP_UFFD_RWP_ALL (MM_CP_UFFD_RWP | \
MM_CP_UFFD_RWP_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, vm_flags_t 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]);
}
static inline unsigned long get_mm_counter_sum(struct mm_struct *mm, int member)
{
return percpu_counter_sum_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_rss_sum(struct mm_struct *mm)
{
return get_mm_counter_sum(mm, MM_FILEPAGES) +
get_mm_counter_sum(mm, MM_ANONPAGES) +
get_mm_counter_sum(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 (data_race(mm->hiwater_rss) < _rss)
data_race(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 */
extern pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
spinlock_t **ptl);
#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 */
enum pt_flags {
PT_kernel = PG_referenced,
PT_reserved = PG_reserved,
/* High bits are used for zone/node/section */
};
static inline struct ptdesc *virt_to_ptdesc(const void *x)
{
return page_ptdesc(virt_to_page(x));
}
/**
* ptdesc_address - Virtual address of page table.
* @pt: Page table descriptor.
*
* Return: The first byte of the page table described by @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 test_bit(PT_reserved, &pt->pt_flags.f);
}
/**
* ptdesc_set_kernel - Mark a ptdesc used to map the kernel
* @ptdesc: The ptdesc to be marked
*
* Kernel page tables often need special handling. Set a flag so that
* the handling code knows this ptdesc will not be used for userspace.
*/
static inline void ptdesc_set_kernel(struct ptdesc *ptdesc)
{
set_bit(PT_kernel, &ptdesc->pt_flags.f);
}
/**
* ptdesc_clear_kernel - Mark a ptdesc as no longer used to map the kernel
* @ptdesc: The ptdesc to be unmarked
*
* Use when the ptdesc is no longer used to map the kernel and no longer
* needs special handling.
*/
static inline void ptdesc_clear_kernel(struct ptdesc *ptdesc)
{
/*
* Note: the 'PG_referenced' bit does not strictly need to be
* cleared before freeing the page. But this is nice for
* symmetry.
*/
clear_bit(PT_kernel, &ptdesc->pt_flags.f);
}
/**
* ptdesc_test_kernel - Check if a ptdesc is used to map the kernel
* @ptdesc: The ptdesc being tested
*
* Call to tell if the ptdesc used to map the kernel.
*/
static inline bool ptdesc_test_kernel(const struct ptdesc *ptdesc)
{
return test_bit(PT_kernel, &ptdesc->pt_flags.f);
}
/**
* 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__))
static inline void __pagetable_free(struct ptdesc *pt)
{
struct page *page = ptdesc_page(pt);
__free_pages(page, compound_order(page));
}
#ifdef CONFIG_ASYNC_KERNEL_PGTABLE_FREE
void pagetable_free_kernel(struct ptdesc *pt);
#else
static inline void pagetable_free_kernel(struct ptdesc *pt)
{
__pagetable_free(pt);
}
#endif
/**
* 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)
{
if (ptdesc_test_kernel(pt)) {
ptdesc_clear_kernel(pt);
pagetable_free_kernel(pt);
} else {
__pagetable_free(pt);
}
}
#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 void __pagetable_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_dtor(struct ptdesc *ptdesc)
{
struct folio *folio = ptdesc_folio(ptdesc);
ptlock_free(ptdesc);
__folio_clear_pgtable(folio);
lruvec_stat_sub_folio(folio, NR_PAGETABLE);
}
static inline void pagetable_dtor_free(struct ptdesc *ptdesc)
{
pagetable_dtor(ptdesc);
pagetable_free(ptdesc);
}
static inline bool pagetable_pte_ctor(struct mm_struct *mm,
struct ptdesc *ptdesc)
{
if (mm != &init_mm && !ptlock_init(ptdesc))
return false;
__pagetable_ctor(ptdesc);
return true;
}
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);
pte_t *pte_offset_map_ro_nolock(struct mm_struct *mm, pmd_t *pmd,
unsigned long addr, spinlock_t **ptlp);
pte_t *pte_offset_map_rw_nolock(struct mm_struct *mm, pmd_t *pmd,
unsigned long addr, pmd_t *pmdvalp,
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);
}
#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; }
#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 mm_struct *mm,
struct ptdesc *ptdesc)
{
if (mm != &init_mm && !pmd_ptlock_init(ptdesc))
return false;
ptdesc_pmd_pts_init(ptdesc);
__pagetable_ctor(ptdesc);
return true;
}
/*
* 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)
{
__pagetable_ctor(ptdesc);
}
static inline void pagetable_p4d_ctor(struct ptdesc *ptdesc)
{
__pagetable_ctor(ptdesc);
}
static inline void pagetable_pgd_ctor(struct ptdesc *ptdesc)
{
__pagetable_ctor(ptdesc);
}
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);
void free_reserved_pages(struct page *page, unsigned int order);
static inline void free_reserved_page(struct page *page)
{
free_reserved_pages(page, 0);
}
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;
}
/*
* FIXME: 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 arch_zone_limits_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, const 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, const 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 mapping_rmap_tree_insert(struct vm_area_struct *vma,
struct address_space *mapping);
void mapping_rmap_tree_insert_after(struct vm_area_struct *vma,
struct vm_area_struct *prev,
struct address_space *mapping);
void mapping_rmap_tree_remove(struct vm_area_struct *vma,
struct address_space *mapping);
struct vm_area_struct *
mapping_rmap_tree_iter_first(struct address_space *mapping,
pgoff_t pgoff_start, pgoff_t pgoff_last);
struct vm_area_struct *
mapping_rmap_tree_iter_next(struct vm_area_struct *vma,
pgoff_t pgoff_start, pgoff_t pgoff_last);
#define mapping_rmap_tree_foreach(vma, mapping, pgoff_start, pgoff_last) \
for (vma = mapping_rmap_tree_iter_first(mapping, pgoff_start, \
pgoff_last); \
vma; vma = mapping_rmap_tree_iter_next(vma, pgoff_start, \
pgoff_last))
void anon_rmap_tree_insert(struct anon_vma_chain *avc,
struct anon_vma *anon_vma);
void anon_rmap_tree_remove(struct anon_vma_chain *avc,
struct anon_vma *anon_vma);
struct anon_vma_chain *
anon_rmap_tree_iter_first(struct anon_vma *anon_vma,
pgoff_t pgoff_start, pgoff_t pgoff_last);
struct anon_vma_chain *
anon_rmap_tree_iter_next(struct anon_vma_chain *avc,
pgoff_t pgoff_start, pgoff_t pgoff_last);
#ifdef CONFIG_DEBUG_VM_RB
void anon_rmap_tree_verify(struct anon_vma_chain *avc);
#endif
#define anon_rmap_tree_foreach(avc, anon_vma, pgoff_start, pgoff_last) \
for (avc = anon_rmap_tree_iter_first(anon_vma, pgoff_start, pgoff_last); \
avc; avc = anon_rmap_tree_iter_next(avc, pgoff_start, pgoff_last))
/* mmap.c */
extern int __vm_enough_memory(const struct mm_struct *mm, long pages, int cap_sys_admin);
extern void exit_mmap(struct mm_struct *);
bool mmap_read_lock_maybe_expand(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, bool write);
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 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);
struct vm_area_struct *_install_special_mapping(struct mm_struct *mm,
unsigned long addr, unsigned long len,
vm_flags_t vm_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,
vma_flags_t vma_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,
EMPTY_VMA_FLAGS);
}
unsigned long do_mmap(struct file *file, unsigned long addr,
unsigned long len, unsigned long prot, unsigned long flags,
vma_flags_t vma_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 */
int __must_check vm_brk_flags(unsigned long addr, unsigned long request, bool is_exec);
int vm_munmap(unsigned long start, size_t len);
unsigned long __must_check vm_mmap(struct file *file, unsigned long addr,
unsigned long len, unsigned long prot,
unsigned long flag, unsigned long offset);
unsigned long __must_check vm_mmap_shadow_stack(unsigned long addr,
unsigned long len, unsigned long flags);
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 */
void truncate_inode_pages(struct address_space *mapping, loff_t lstart);
void truncate_inode_pages_range(struct address_space *mapping, loff_t lstart,
uoff_t lend);
void truncate_inode_pages_final(struct address_space *mapping);
/* 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);
/* 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(const 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(const 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(const 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(const struct vm_area_struct *vma)
{
return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
}
/**
* vma_start_pgoff() - Get the page offset of the start of @vma
* @vma: The VMA whose page offset is required.
*
* If the VMA is file-backed, this is the page offset into the file.
*
* If @vma is anonymous, this is the virtual page offset of the start of the
* VMA - if unfaulted, then vma->vm_start >> PAGE_SHIFT, if faulted then the
* virtual page offset at the time of first fault.
*
* If @vma is a MAP_PRIVATE file-backed mapping, then this returns the
* page offset within the file.
*
* Edge cases: nommu does not abide by these, MAP_PRIVATE-/dev/zero satisfies
* vma_is_anonymous() but has file-backed page offset, and MAP_PRIVATE-pfnmap
* regions have their page offset set to the first PFN in the range.
*
* Returns: The page offset of the start of @vma.
*/
static inline pgoff_t vma_start_pgoff(const struct vm_area_struct *vma)
{
return vma->vm_pgoff;
}
/**
* vma_end_pgoff() - Get the page offset of the exclusive end of @vma
* @vma: The VMA whose end page offset is required.
*
* This returns the exclusive end page offset of @vma, which is useful for
* expressing page offset ranges.
*
* See the description of vma_start_pgoff() for a description of VMA page
* offsets.
*
* Returns: The exclusive end page offset of @vma.
*/
static inline pgoff_t vma_end_pgoff(const struct vm_area_struct *vma)
{
return vma_start_pgoff(vma) + vma_pages(vma);
}
/**
* vma_last_pgoff() - Get the page offset of the last page in @vma
* @vma: The VMA whose last page offset is required.
*
* This returns the last page offset contained within @vma.
*
* See the description of vma_start_pgoff() for a description of VMA page
* offsets.
*
* Returns: The last page offset of @vma.
*/
static inline pgoff_t vma_last_pgoff(const struct vm_area_struct *vma)
{
return vma_end_pgoff(vma) - 1;
}
/**
* vma_start_anon_pgoff() - Get the anonymous page offset of the start of @vma
* @vma: The VMA whose anonymous page offset is required.
*
* If unfaulted, then this is vma->vm_start >> PAGE_SHIFT, if faulted then the
* anonymous page offset at the time of first fault.
*
* If the VMA is anonymous, this returns the same value as vma_start_pgoff().
*
* This value is used for tracking MAP_PRIVATE file-backed mappings by their
* anonymous page offset.
*
* Returns: The anonymous page offset of the start of @vma.
*/
static inline pgoff_t vma_start_anon_pgoff(const struct vm_area_struct *vma)
{
pgoff_t pgoff = 0;
#ifdef CONFIG_64BIT
pgoff += vma->__vm_anon_pgoff_hi;
pgoff <<= 32;
#endif
pgoff += vma->__vm_anon_pgoff_lo;
return pgoff;
}
/**
* vma_end_anon_pgoff() - Get the anonymous page offset of the exclusive end of
* @vma.
* @vma: The VMA whose end anonymous page offset is required.
*
* This returns the anonymous exclusive end page offset of @vma, which is useful
* for expressing page offset ranges.
*
* See the description of vma_start_anon_pgoff() for a description of VMA
* anonymous page offsets.
*
* Returns: The exclusive end anonymous page offset of @vma.
*/
static inline pgoff_t vma_end_anon_pgoff(const struct vm_area_struct *vma)
{
return vma_start_anon_pgoff(vma) + vma_pages(vma);
}
/**
* vma_last_anon_pgoff() - Get the anonymous page offset of the last page in
* @vma.
* @vma: The VMA whose last anonymous page offset is required.
*
* See the description of vma_start_anon_pgoff() for a description of VMA
* anonymous page offsets.
*
* Returns: The last anonymous page offset of @vma.
*/
static inline pgoff_t vma_last_anon_pgoff(const struct vm_area_struct *vma)
{
return vma_end_anon_pgoff(vma) - 1;
}
static inline unsigned long vma_desc_size(const struct vm_area_desc *desc)
{
return desc->end - desc->start;
}
static inline unsigned long vma_desc_pages(const struct vm_area_desc *desc)
{
return vma_desc_size(desc) >> PAGE_SHIFT;
}
/**
* mmap_action_remap - helper for mmap_prepare hook to specify that a pure PFN
* remap is required.
* @desc: The VMA descriptor for the VMA requiring remap.
* @start: The virtual address to start the remap from, must be within the VMA.
* @start_pfn: The first PFN in the range to remap.
* @size: The size of the range to remap, in bytes, at most spanning to the end
* of the VMA.
*/
static inline void mmap_action_remap(struct vm_area_desc *desc,
unsigned long start,
unsigned long start_pfn,
unsigned long size)
{
struct mmap_action *action = &desc->action;
/* [start, start + size) must be within the VMA. */
WARN_ON_ONCE(start < desc->start || start >= desc->end);
WARN_ON_ONCE(start + size > desc->end);
action->type = MMAP_REMAP_PFN;
action->remap.start = start;
action->remap.start_pfn = start_pfn;
action->remap.size = size;
action->remap.pgprot = desc->page_prot;
}
/**
* mmap_action_remap_full - helper for mmap_prepare hook to specify that the
* entirety of a VMA should be PFN remapped.
* @desc: The VMA descriptor for the VMA requiring remap.
* @start_pfn: The first PFN in the range to remap.
*/
static inline void mmap_action_remap_full(struct vm_area_desc *desc,
unsigned long start_pfn)
{
mmap_action_remap(desc, desc->start, start_pfn, vma_desc_size(desc));
}
/**
* mmap_action_ioremap - helper for mmap_prepare hook to specify that a pure PFN
* I/O remap is required.
* @desc: The VMA descriptor for the VMA requiring remap.
* @start: The virtual address to start the remap from, must be within the VMA.
* @start_pfn: The first PFN in the range to remap.
* @size: The size of the range to remap, in bytes, at most spanning to the end
* of the VMA.
*/
static inline void mmap_action_ioremap(struct vm_area_desc *desc,
unsigned long start,
unsigned long start_pfn,
unsigned long size)
{
mmap_action_remap(desc, start, start_pfn, size);
desc->action.type = MMAP_IO_REMAP_PFN;
}
/**
* mmap_action_ioremap_full - helper for mmap_prepare hook to specify that the
* entirety of a VMA should be PFN I/O remapped.
* @desc: The VMA descriptor for the VMA requiring remap.
* @start_pfn: The first PFN in the range to remap.
*/
static inline void mmap_action_ioremap_full(struct vm_area_desc *desc,
unsigned long start_pfn)
{
mmap_action_ioremap(desc, desc->start, start_pfn, vma_desc_size(desc));
}
/**
* mmap_action_simple_ioremap - helper for mmap_prepare hook to specify that the
* physical range in [start_phys_addr, start_phys_addr + size) should be I/O
* remapped.
* @desc: The VMA descriptor for the VMA requiring remap.
* @start_phys_addr: Start of the physical memory to be mapped.
* @size: Size of the area to map.
*
* NOTE: Some drivers might want to tweak desc->page_prot for purposes of
* write-combine or similar.
*/
static inline void mmap_action_simple_ioremap(struct vm_area_desc *desc,
phys_addr_t start_phys_addr,
unsigned long size)
{
struct mmap_action *action = &desc->action;
action->simple_ioremap.start_phys_addr = start_phys_addr;
action->simple_ioremap.size = size;
action->type = MMAP_SIMPLE_IO_REMAP;
}
/**
* mmap_action_map_kernel_pages - helper for mmap_prepare hook to specify that
* @num kernel pages contained in the @pages array should be mapped to userland
* starting at virtual address @start.
* @desc: The VMA descriptor for the VMA requiring kernel pags to be mapped.
* @start: The virtual address from which to map them.
* @pages: An array of struct page pointers describing the memory to map.
* @nr_pages: The number of entries in the @pages aray.
*/
static inline void mmap_action_map_kernel_pages(struct vm_area_desc *desc,
unsigned long start, struct page **pages,
unsigned long nr_pages)
{
struct mmap_action *action = &desc->action;
action->type = MMAP_MAP_KERNEL_PAGES;
action->map_kernel.start = start;
action->map_kernel.pages = pages;
action->map_kernel.nr_pages = nr_pages;
action->map_kernel.pgoff = desc->pgoff;
}
/**
* mmap_action_map_kernel_pages_full - helper for mmap_prepare hook to specify that
* kernel pages contained in the @pages array should be mapped to userland
* from @desc->start to @desc->end.
* @desc: The VMA descriptor for the VMA requiring kernel pags to be mapped.
* @pages: An array of struct page pointers describing the memory to map.
*
* The caller must ensure that @pages contains sufficient entries to cover the
* entire range described by @desc.
*/
static inline void mmap_action_map_kernel_pages_full(struct vm_area_desc *desc,
struct page **pages)
{
mmap_action_map_kernel_pages(desc, desc->start, pages,
vma_desc_pages(desc));
}
int mmap_action_prepare(struct vm_area_desc *desc);
int mmap_action_complete(struct vm_area_struct *vma,
struct mmap_action *action, bool is_compat);
/* 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;
}
/**
* range_is_subset - Is the specified inner range a subset of the outer range?
* @outer_start: The start of the outer range.
* @outer_end: The exclusive end of the outer range.
* @inner_start: The start of the inner range.
* @inner_end: The exclusive end of the inner range.
*
* Returns: %true if [inner_start, inner_end) is a subset of [outer_start,
* outer_end), otherwise %false.
*/
static inline bool range_is_subset(unsigned long outer_start,
unsigned long outer_end,
unsigned long inner_start,
unsigned long inner_end)
{
return outer_start <= inner_start && inner_end <= outer_end;
}
/**
* range_in_vma - is the specified [@start, @end) range a subset of the VMA?
* @vma: The VMA against which we want to check [@start, @end).
* @start: The start of the range we wish to check.
* @end: The exclusive end of the range we wish to check.
*
* Returns: %true if [@start, @end) is a subset of [@vma->vm_start,
* @vma->vm_end), %false otherwise.
*/
static inline bool range_in_vma(const struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
if (!vma)
return false;
return range_is_subset(vma->vm_start, vma->vm_end, start, end);
}
/**
* range_in_vma_desc - is the specified [@start, @end) range a subset of the VMA
* described by @desc, a VMA descriptor?
* @desc: The VMA descriptor against which we want to check [@start, @end).
* @start: The start of the range we wish to check.
* @end: The exclusive end of the range we wish to check.
*
* Returns: %true if [@start, @end) is a subset of [@desc->start, @desc->end),
* %false otherwise.
*/
static inline bool range_in_vma_desc(const struct vm_area_desc *desc,
unsigned long start, unsigned long end)
{
if (!desc)
return false;
return range_is_subset(desc->start, desc->end, start, end);
}
#ifdef CONFIG_MMU
pgprot_t vm_get_page_prot(vm_flags_t vm_flags);
static inline pgprot_t vma_flags_to_page_prot(vma_flags_t vma_flags)
{
const vm_flags_t vm_flags = vma_flags_to_legacy(vma_flags);
return vm_get_page_prot(vm_flags);
}
static inline pgprot_t vma_get_page_prot(const struct vm_area_struct *vma)
{
return vma_flags_to_page_prot(vma->flags);
}
void vma_set_page_prot(struct vm_area_struct *vma);
#else
static inline pgprot_t vm_get_page_prot(vm_flags_t vm_flags)
{
return __pgprot(0);
}
static inline pgprot_t vma_flags_to_page_prot(vma_flags_t vma_flags)
{
return __pgprot(0);
}
static inline pgprot_t vma_get_page_prot(const struct vm_area_struct *vma)
{
return __pgprot(0);
}
static inline void vma_set_page_prot(struct vm_area_struct *vma)
{
vma->vm_page_prot = vma_get_page_prot(vma);
}
#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 *vma, unsigned long addr,
unsigned long pfn, unsigned long size, pgprot_t pgprot);
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 map_kernel_pages_prepare(struct vm_area_desc *desc);
int map_kernel_pages_complete(struct vm_area_struct *vma,
struct mmap_action *action);
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_page_mkwrite(struct vm_fault *vmf, struct page *page,
bool write);
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,
unsigned long pfn);
vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
unsigned long addr, unsigned long 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_pfn
static inline unsigned long io_remap_pfn_range_pfn(unsigned long pfn,
unsigned long size)
{
return pfn;
}
#endif
static inline int io_remap_pfn_range(struct vm_area_struct *vma,
unsigned long addr, unsigned long orig_pfn,
unsigned long size, pgprot_t orig_prot)
{
const unsigned long pfn = io_remap_pfn_range_pfn(orig_pfn, size);
const pgprot_t prot = pgprot_decrypted(orig_prot);
return remap_pfn_range(vma, addr, pfn, size, prot);
}
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 or userfaultfd RWP) fault is required.
*/
static inline bool gup_can_follow_protnone(const struct vm_area_struct *vma,
unsigned int flags)
{
/*
* VM_UFFD_RWP uses protnone as an access-tracking marker, not for
* NUMA hinting. GUP must always take a fault so the access is
* delivered to userfaultfd, regardless of FOLL_HONOR_NUMA_FAULT.
*
* Only do so while the VMA is accessible. If it has been made
* inaccessible (e.g. mprotect(PROT_NONE)), fall through to the guard
* below: forcing a fault there would loop, as handle_mm_fault() makes
* no progress on protnone in an inaccessible VMA, and the access is
* denied regardless of RWP anyway.
*/
if (vma_test_single_mask(vma, VMA_UFFD_RWP) && vma_is_accessible(vma))
return false;
/*
* 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)
{
iommu_debug_check_unmapped(page, numpages);
if (debug_pagealloc_enabled_static())
__kernel_map_pages(page, numpages, 1);
}
static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages)
{
iommu_debug_check_unmapped(page, 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(const 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(const 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 */
#ifndef clear_pages
/**
* clear_pages() - clear a page range for kernel-internal use.
* @addr: start address
* @npages: number of pages
*
* Use clear_user_pages() instead when clearing a page range to be
* mapped to user space.
*
* Does absolutely no exception handling.
*
* Note that even though the clearing operation is preemptible, clear_pages()
* does not (and on architectures where it reduces to a few long-running
* instructions, might not be able to) call cond_resched() to check if
* rescheduling is required.
*
* When running under preemptible models this is not a problem. Under
* cooperatively scheduled models, however, the caller is expected to
* limit @npages to no more than PROCESS_PAGES_NON_PREEMPT_BATCH.
*/
static inline void clear_pages(void *addr, unsigned int npages)
{
do {
clear_page(addr);
addr += PAGE_SIZE;
} while (--npages);
}
#endif
#ifndef PROCESS_PAGES_NON_PREEMPT_BATCH
#ifdef clear_pages
/*
* The architecture defines clear_pages(), and we assume that it is
* generally "fast". So choose a batch size large enough to allow the processor
* headroom for optimizing the operation and yet small enough that we see
* reasonable preemption latency for when this optimization is not possible
* (ex. slow microarchitectures, memory bandwidth saturation.)
*
* With a value of 32MB and assuming a memory bandwidth of ~10GBps, this should
* result in worst case preemption latency of around 3ms when clearing pages.
*
* (See comment above clear_pages() for why preemption latency is a concern
* here.)
*/
#define PROCESS_PAGES_NON_PREEMPT_BATCH (SZ_32M >> PAGE_SHIFT)
#else /* !clear_pages */
/*
* The architecture does not provide a clear_pages() implementation. Assume
* that clear_page() -- which clear_pages() will fallback to -- is relatively
* slow and choose a small value for PROCESS_PAGES_NON_PREEMPT_BATCH.
*/
#define PROCESS_PAGES_NON_PREEMPT_BATCH 1
#endif
#endif
#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 */
bool process_shares_mm(const struct task_struct *p, const struct mm_struct *mm);
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
unsigned long section_map_size(void);
struct page * __populate_section_memmap(unsigned long pfn,
unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
struct dev_pagemap *pgmap);
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);
int vmemmap_populate_hvo(unsigned long start, unsigned long end,
unsigned int order, struct zone *zone,
unsigned long headsize);
void vmemmap_wrprotect_hvo(unsigned long start, unsigned long end, int node,
unsigned long headsize);
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(const 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(const 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
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 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);
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 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_PFN_MAP,
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);
#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
#ifdef CONFIG_ANON_VMA_NAME
int set_anon_vma_name(unsigned long addr, unsigned long size,
const char __user *uname);
#else
static inline
int set_anon_vma_name(unsigned long addr, unsigned long size,
const char __user *uname)
{
return -EINVAL;
}
#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);
int reserve_mem_release_by_name(const char *name);
#ifdef CONFIG_64BIT
void mseal_mmap_page_zero(void);
#else
static inline void mseal_mmap_page_zero(void) {}
#endif
/*
* user_alloc_needs_zeroing checks if a user folio from page allocator needs to
* be zeroed or not.
*/
static inline bool user_alloc_needs_zeroing(void)
{
/*
* for user folios, arch with cache aliasing requires cache flush and
* arc changes folio->flags to make icache coherent with dcache, so
* always return false to make caller use
* clear_user_page()/clear_user_highpage().
*/
return cpu_dcache_is_aliasing() || cpu_icache_is_aliasing() ||
!static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
&init_on_alloc);
}
int arch_get_shadow_stack_status(struct task_struct *t, unsigned long __user *status);
int arch_set_shadow_stack_status(struct task_struct *t, unsigned long status);
int arch_lock_shadow_stack_status(struct task_struct *t, unsigned long status);
/*
* DMA mapping IDs for page_pool
*
* When DMA-mapping a page, page_pool allocates an ID (from an xarray) and
* stashes it in the upper bits of page->pp_magic. We always want to be able to
* unambiguously identify page pool pages (using page_pool_page_is_pp()). Non-PP
* pages can have arbitrary kernel pointers stored in the same field as pp_magic
* (since it overlaps with page->lru.next), so we must ensure that we cannot
* mistake a valid kernel pointer with any of the values we write into this
* field.
*
* On architectures that set POISON_POINTER_DELTA, this is already ensured,
* since this value becomes part of PP_SIGNATURE; meaning we can just use the
* space between the PP_SIGNATURE value (without POISON_POINTER_DELTA), and the
* lowest bits of POISON_POINTER_DELTA. On arches where POISON_POINTER_DELTA is
* 0, we use the lowest bit of PAGE_OFFSET as the boundary if that value is
* known at compile-time.
*
* If the value of PAGE_OFFSET is not known at compile time, or if it is too
* small to leave at least 8 bits available above PP_SIGNATURE, we define the
* number of bits to be 0, which turns off the DMA index tracking altogether
* (see page_pool_register_dma_index()).
*/
#define PP_DMA_INDEX_SHIFT (1 + __fls(PP_SIGNATURE - POISON_POINTER_DELTA))
#if POISON_POINTER_DELTA > 0
/* PP_SIGNATURE includes POISON_POINTER_DELTA, so limit the size of the DMA
* index to not overlap with that if set
*/
#define PP_DMA_INDEX_BITS MIN(32, __ffs(POISON_POINTER_DELTA) - PP_DMA_INDEX_SHIFT)
#else
/* Use the lowest bit of PAGE_OFFSET if there's at least 8 bits available; see above */
#define PP_DMA_INDEX_MIN_OFFSET (1 << (PP_DMA_INDEX_SHIFT + 8))
#define PP_DMA_INDEX_BITS ((__builtin_constant_p(PAGE_OFFSET) && \
PAGE_OFFSET >= PP_DMA_INDEX_MIN_OFFSET && \
!(PAGE_OFFSET & (PP_DMA_INDEX_MIN_OFFSET - 1))) ? \
MIN(32, __ffs(PAGE_OFFSET) - PP_DMA_INDEX_SHIFT) : 0)
#endif
#define PP_DMA_INDEX_MASK GENMASK(PP_DMA_INDEX_BITS + PP_DMA_INDEX_SHIFT - 1, \
PP_DMA_INDEX_SHIFT)
/* Mask used for checking in page_pool_page_is_pp() below. page->pp_magic is
* OR'ed with PP_SIGNATURE after the allocation in order to preserve bit 0 for
* the head page of compound page and bit 1 for pfmemalloc page, as well as the
* bits used for the DMA index. page_is_pfmemalloc() is checked in
* __page_pool_put_page() to avoid recycling the pfmemalloc page.
*/
#define PP_MAGIC_MASK ~(PP_DMA_INDEX_MASK | 0x3UL)
#ifdef CONFIG_PAGE_POOL
static inline bool page_pool_page_is_pp(const struct page *page)
{
return (page->pp_magic & PP_MAGIC_MASK) == PP_SIGNATURE;
}
#else
static inline bool page_pool_page_is_pp(const struct page *page)
{
return false;
}
#endif
#define PAGE_SNAPSHOT_FAITHFUL (1 << 0)
#define PAGE_SNAPSHOT_PG_BUDDY (1 << 1)
#define PAGE_SNAPSHOT_PG_IDLE (1 << 2)
struct page_snapshot {
struct folio folio_snapshot;
struct page page_snapshot;
unsigned long pfn;
unsigned long idx;
unsigned long flags;
};
static inline bool snapshot_page_is_faithful(const struct page_snapshot *ps)
{
return ps->flags & PAGE_SNAPSHOT_FAITHFUL;
}
void snapshot_page(struct page_snapshot *ps, const struct page *page);
void map_anon_folio_pte_nopf(struct folio *folio, pte_t *pte,
struct vm_area_struct *vma, unsigned long addr,
bool uffd_wp);
#endif /* _LINUX_MM_H */