1 /* SPDX-License-Identifier: GPL-2.0 */
5 #include <linux/errno.h>
9 #include <linux/mmdebug.h>
10 #include <linux/gfp.h>
11 #include <linux/bug.h>
12 #include <linux/list.h>
13 #include <linux/mmzone.h>
14 #include <linux/rbtree.h>
15 #include <linux/atomic.h>
16 #include <linux/debug_locks.h>
17 #include <linux/mm_types.h>
18 #include <linux/range.h>
19 #include <linux/pfn.h>
20 #include <linux/percpu-refcount.h>
21 #include <linux/bit_spinlock.h>
22 #include <linux/shrinker.h>
23 #include <linux/resource.h>
24 #include <linux/page_ext.h>
25 #include <linux/err.h>
26 #include <linux/page_ref.h>
27 #include <linux/memremap.h>
28 #include <linux/overflow.h>
29 #include <linux/sizes.h>
30 #include <linux/sched.h>
34 struct anon_vma_chain;
37 struct writeback_control;
40 void init_mm_internals(void);
42 #ifndef CONFIG_NEED_MULTIPLE_NODES /* Don't use mapnrs, do it properly */
43 extern unsigned long max_mapnr;
45 static inline void set_max_mapnr(unsigned long limit)
50 static inline void set_max_mapnr(unsigned long limit) { }
53 extern atomic_long_t _totalram_pages;
54 static inline unsigned long totalram_pages(void)
56 return (unsigned long)atomic_long_read(&_totalram_pages);
59 static inline void totalram_pages_inc(void)
61 atomic_long_inc(&_totalram_pages);
64 static inline void totalram_pages_dec(void)
66 atomic_long_dec(&_totalram_pages);
69 static inline void totalram_pages_add(long count)
71 atomic_long_add(count, &_totalram_pages);
74 extern void * high_memory;
75 extern int page_cluster;
78 extern int sysctl_legacy_va_layout;
80 #define sysctl_legacy_va_layout 0
83 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
84 extern const int mmap_rnd_bits_min;
85 extern const int mmap_rnd_bits_max;
86 extern int mmap_rnd_bits __read_mostly;
88 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
89 extern const int mmap_rnd_compat_bits_min;
90 extern const int mmap_rnd_compat_bits_max;
91 extern int mmap_rnd_compat_bits __read_mostly;
95 #include <asm/pgtable.h>
96 #include <asm/processor.h>
99 * Architectures that support memory tagging (assigning tags to memory regions,
100 * embedding these tags into addresses that point to these memory regions, and
101 * checking that the memory and the pointer tags match on memory accesses)
102 * redefine this macro to strip tags from pointers.
103 * It's defined as noop for arcitectures that don't support memory tagging.
105 #ifndef untagged_addr
106 #define untagged_addr(addr) (addr)
110 #define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0))
114 #define page_to_virt(x) __va(PFN_PHYS(page_to_pfn(x)))
118 #define lm_alias(x) __va(__pa_symbol(x))
122 * To prevent common memory management code establishing
123 * a zero page mapping on a read fault.
124 * This macro should be defined within <asm/pgtable.h>.
125 * s390 does this to prevent multiplexing of hardware bits
126 * related to the physical page in case of virtualization.
128 #ifndef mm_forbids_zeropage
129 #define mm_forbids_zeropage(X) (0)
133 * On some architectures it is expensive to call memset() for small sizes.
134 * If an architecture decides to implement their own version of
135 * mm_zero_struct_page they should wrap the defines below in a #ifndef and
136 * define their own version of this macro in <asm/pgtable.h>
138 #if BITS_PER_LONG == 64
139 /* This function must be updated when the size of struct page grows above 80
140 * or reduces below 56. The idea that compiler optimizes out switch()
141 * statement, and only leaves move/store instructions. Also the compiler can
142 * combine write statments if they are both assignments and can be reordered,
143 * this can result in several of the writes here being dropped.
145 #define mm_zero_struct_page(pp) __mm_zero_struct_page(pp)
146 static inline void __mm_zero_struct_page(struct page *page)
148 unsigned long *_pp = (void *)page;
150 /* Check that struct page is either 56, 64, 72, or 80 bytes */
151 BUILD_BUG_ON(sizeof(struct page) & 7);
152 BUILD_BUG_ON(sizeof(struct page) < 56);
153 BUILD_BUG_ON(sizeof(struct page) > 80);
155 switch (sizeof(struct page)) {
157 _pp[9] = 0; /* fallthrough */
159 _pp[8] = 0; /* fallthrough */
161 _pp[7] = 0; /* fallthrough */
173 #define mm_zero_struct_page(pp) ((void)memset((pp), 0, sizeof(struct page)))
177 * Default maximum number of active map areas, this limits the number of vmas
178 * per mm struct. Users can overwrite this number by sysctl but there is a
181 * When a program's coredump is generated as ELF format, a section is created
182 * per a vma. In ELF, the number of sections is represented in unsigned short.
183 * This means the number of sections should be smaller than 65535 at coredump.
184 * Because the kernel adds some informative sections to a image of program at
185 * generating coredump, we need some margin. The number of extra sections is
186 * 1-3 now and depends on arch. We use "5" as safe margin, here.
188 * ELF extended numbering allows more than 65535 sections, so 16-bit bound is
189 * not a hard limit any more. Although some userspace tools can be surprised by
192 #define MAPCOUNT_ELF_CORE_MARGIN (5)
193 #define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
195 extern int sysctl_max_map_count;
197 extern unsigned long sysctl_user_reserve_kbytes;
198 extern unsigned long sysctl_admin_reserve_kbytes;
200 extern int sysctl_overcommit_memory;
201 extern int sysctl_overcommit_ratio;
202 extern unsigned long sysctl_overcommit_kbytes;
204 extern int overcommit_ratio_handler(struct ctl_table *, int, void __user *,
206 extern int overcommit_kbytes_handler(struct ctl_table *, int, void __user *,
209 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
211 /* to align the pointer to the (next) page boundary */
212 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
214 /* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
215 #define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)(addr), PAGE_SIZE)
217 #define lru_to_page(head) (list_entry((head)->prev, struct page, lru))
220 * Linux kernel virtual memory manager primitives.
221 * The idea being to have a "virtual" mm in the same way
222 * we have a virtual fs - giving a cleaner interface to the
223 * mm details, and allowing different kinds of memory mappings
224 * (from shared memory to executable loading to arbitrary
228 struct vm_area_struct *vm_area_alloc(struct mm_struct *);
229 struct vm_area_struct *vm_area_dup(struct vm_area_struct *);
230 void vm_area_free(struct vm_area_struct *);
233 extern struct rb_root nommu_region_tree;
234 extern struct rw_semaphore nommu_region_sem;
236 extern unsigned int kobjsize(const void *objp);
240 * vm_flags in vm_area_struct, see mm_types.h.
241 * When changing, update also include/trace/events/mmflags.h
243 #define VM_NONE 0x00000000
245 #define VM_READ 0x00000001 /* currently active flags */
246 #define VM_WRITE 0x00000002
247 #define VM_EXEC 0x00000004
248 #define VM_SHARED 0x00000008
250 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
251 #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */
252 #define VM_MAYWRITE 0x00000020
253 #define VM_MAYEXEC 0x00000040
254 #define VM_MAYSHARE 0x00000080
256 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */
257 #define VM_UFFD_MISSING 0x00000200 /* missing pages tracking */
258 #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */
259 #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */
260 #define VM_UFFD_WP 0x00001000 /* wrprotect pages tracking */
262 #define VM_LOCKED 0x00002000
263 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */
265 /* Used by sys_madvise() */
266 #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */
267 #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */
269 #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */
270 #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */
271 #define VM_LOCKONFAULT 0x00080000 /* Lock the pages covered when they are faulted in */
272 #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */
273 #define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */
274 #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */
275 #define VM_SYNC 0x00800000 /* Synchronous page faults */
276 #define VM_ARCH_1 0x01000000 /* Architecture-specific flag */
277 #define VM_WIPEONFORK 0x02000000 /* Wipe VMA contents in child. */
278 #define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */
280 #ifdef CONFIG_MEM_SOFT_DIRTY
281 # define VM_SOFTDIRTY 0x08000000 /* Not soft dirty clean area */
283 # define VM_SOFTDIRTY 0
286 #define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */
287 #define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */
288 #define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */
289 #define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */
291 #ifdef CONFIG_ARCH_USES_HIGH_VMA_FLAGS
292 #define VM_HIGH_ARCH_BIT_0 32 /* bit only usable on 64-bit architectures */
293 #define VM_HIGH_ARCH_BIT_1 33 /* bit only usable on 64-bit architectures */
294 #define VM_HIGH_ARCH_BIT_2 34 /* bit only usable on 64-bit architectures */
295 #define VM_HIGH_ARCH_BIT_3 35 /* bit only usable on 64-bit architectures */
296 #define VM_HIGH_ARCH_BIT_4 36 /* bit only usable on 64-bit architectures */
297 #define VM_HIGH_ARCH_0 BIT(VM_HIGH_ARCH_BIT_0)
298 #define VM_HIGH_ARCH_1 BIT(VM_HIGH_ARCH_BIT_1)
299 #define VM_HIGH_ARCH_2 BIT(VM_HIGH_ARCH_BIT_2)
300 #define VM_HIGH_ARCH_3 BIT(VM_HIGH_ARCH_BIT_3)
301 #define VM_HIGH_ARCH_4 BIT(VM_HIGH_ARCH_BIT_4)
302 #endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */
304 #ifdef CONFIG_ARCH_HAS_PKEYS
305 # define VM_PKEY_SHIFT VM_HIGH_ARCH_BIT_0
306 # define VM_PKEY_BIT0 VM_HIGH_ARCH_0 /* A protection key is a 4-bit value */
307 # define VM_PKEY_BIT1 VM_HIGH_ARCH_1 /* on x86 and 5-bit value on ppc64 */
308 # define VM_PKEY_BIT2 VM_HIGH_ARCH_2
309 # define VM_PKEY_BIT3 VM_HIGH_ARCH_3
311 # define VM_PKEY_BIT4 VM_HIGH_ARCH_4
313 # define VM_PKEY_BIT4 0
315 #endif /* CONFIG_ARCH_HAS_PKEYS */
317 #if defined(CONFIG_X86)
318 # define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */
319 #elif defined(CONFIG_PPC)
320 # define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */
321 #elif defined(CONFIG_PARISC)
322 # define VM_GROWSUP VM_ARCH_1
323 #elif defined(CONFIG_IA64)
324 # define VM_GROWSUP VM_ARCH_1
325 #elif defined(CONFIG_SPARC64)
326 # define VM_SPARC_ADI VM_ARCH_1 /* Uses ADI tag for access control */
327 # define VM_ARCH_CLEAR VM_SPARC_ADI
328 #elif defined(CONFIG_ARM64)
329 # define VM_ARM64_BTI VM_ARCH_1 /* BTI guarded page, a.k.a. GP bit */
330 # define VM_ARCH_CLEAR VM_ARM64_BTI
331 #elif !defined(CONFIG_MMU)
332 # define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */
336 # define VM_GROWSUP VM_NONE
339 /* Bits set in the VMA until the stack is in its final location */
340 #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ)
342 #define TASK_EXEC ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0)
344 /* Common data flag combinations */
345 #define VM_DATA_FLAGS_TSK_EXEC (VM_READ | VM_WRITE | TASK_EXEC | \
346 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
347 #define VM_DATA_FLAGS_NON_EXEC (VM_READ | VM_WRITE | VM_MAYREAD | \
348 VM_MAYWRITE | VM_MAYEXEC)
349 #define VM_DATA_FLAGS_EXEC (VM_READ | VM_WRITE | VM_EXEC | \
350 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
352 #ifndef VM_DATA_DEFAULT_FLAGS /* arch can override this */
353 #define VM_DATA_DEFAULT_FLAGS VM_DATA_FLAGS_EXEC
356 #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */
357 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
360 #ifdef CONFIG_STACK_GROWSUP
361 #define VM_STACK VM_GROWSUP
363 #define VM_STACK VM_GROWSDOWN
366 #define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
368 /* VMA basic access permission flags */
369 #define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC)
373 * Special vmas that are non-mergable, non-mlock()able.
375 #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP)
377 /* This mask prevents VMA from being scanned with khugepaged */
378 #define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB)
380 /* This mask defines which mm->def_flags a process can inherit its parent */
381 #define VM_INIT_DEF_MASK VM_NOHUGEPAGE
383 /* This mask is used to clear all the VMA flags used by mlock */
384 #define VM_LOCKED_CLEAR_MASK (~(VM_LOCKED | VM_LOCKONFAULT))
386 /* Arch-specific flags to clear when updating VM flags on protection change */
387 #ifndef VM_ARCH_CLEAR
388 # define VM_ARCH_CLEAR VM_NONE
390 #define VM_FLAGS_CLEAR (ARCH_VM_PKEY_FLAGS | VM_ARCH_CLEAR)
393 * mapping from the currently active vm_flags protection bits (the
394 * low four bits) to a page protection mask..
396 extern pgprot_t protection_map[16];
399 * Fault flag definitions.
401 * @FAULT_FLAG_WRITE: Fault was a write fault.
402 * @FAULT_FLAG_MKWRITE: Fault was mkwrite of existing PTE.
403 * @FAULT_FLAG_ALLOW_RETRY: Allow to retry the fault if blocked.
404 * @FAULT_FLAG_RETRY_NOWAIT: Don't drop mmap_sem and wait when retrying.
405 * @FAULT_FLAG_KILLABLE: The fault task is in SIGKILL killable region.
406 * @FAULT_FLAG_TRIED: The fault has been tried once.
407 * @FAULT_FLAG_USER: The fault originated in userspace.
408 * @FAULT_FLAG_REMOTE: The fault is not for current task/mm.
409 * @FAULT_FLAG_INSTRUCTION: The fault was during an instruction fetch.
410 * @FAULT_FLAG_INTERRUPTIBLE: The fault can be interrupted by non-fatal signals.
412 * About @FAULT_FLAG_ALLOW_RETRY and @FAULT_FLAG_TRIED: we can specify
413 * whether we would allow page faults to retry by specifying these two
414 * fault flags correctly. Currently there can be three legal combinations:
416 * (a) ALLOW_RETRY and !TRIED: this means the page fault allows retry, and
417 * this is the first try
419 * (b) ALLOW_RETRY and TRIED: this means the page fault allows retry, and
420 * we've already tried at least once
422 * (c) !ALLOW_RETRY and !TRIED: this means the page fault does not allow retry
424 * The unlisted combination (!ALLOW_RETRY && TRIED) is illegal and should never
425 * be used. Note that page faults can be allowed to retry for multiple times,
426 * in which case we'll have an initial fault with flags (a) then later on
427 * continuous faults with flags (b). We should always try to detect pending
428 * signals before a retry to make sure the continuous page faults can still be
429 * interrupted if necessary.
431 #define FAULT_FLAG_WRITE 0x01
432 #define FAULT_FLAG_MKWRITE 0x02
433 #define FAULT_FLAG_ALLOW_RETRY 0x04
434 #define FAULT_FLAG_RETRY_NOWAIT 0x08
435 #define FAULT_FLAG_KILLABLE 0x10
436 #define FAULT_FLAG_TRIED 0x20
437 #define FAULT_FLAG_USER 0x40
438 #define FAULT_FLAG_REMOTE 0x80
439 #define FAULT_FLAG_INSTRUCTION 0x100
440 #define FAULT_FLAG_INTERRUPTIBLE 0x200
443 * The default fault flags that should be used by most of the
444 * arch-specific page fault handlers.
446 #define FAULT_FLAG_DEFAULT (FAULT_FLAG_ALLOW_RETRY | \
447 FAULT_FLAG_KILLABLE | \
448 FAULT_FLAG_INTERRUPTIBLE)
451 * fault_flag_allow_retry_first - check ALLOW_RETRY the first time
453 * This is mostly used for places where we want to try to avoid taking
454 * the mmap_sem for too long a time when waiting for another condition
455 * to change, in which case we can try to be polite to release the
456 * mmap_sem in the first round to avoid potential starvation of other
457 * processes that would also want the mmap_sem.
459 * Return: true if the page fault allows retry and this is the first
460 * attempt of the fault handling; false otherwise.
462 static inline bool fault_flag_allow_retry_first(unsigned int flags)
464 return (flags & FAULT_FLAG_ALLOW_RETRY) &&
465 (!(flags & FAULT_FLAG_TRIED));
468 #define FAULT_FLAG_TRACE \
469 { FAULT_FLAG_WRITE, "WRITE" }, \
470 { FAULT_FLAG_MKWRITE, "MKWRITE" }, \
471 { FAULT_FLAG_ALLOW_RETRY, "ALLOW_RETRY" }, \
472 { FAULT_FLAG_RETRY_NOWAIT, "RETRY_NOWAIT" }, \
473 { FAULT_FLAG_KILLABLE, "KILLABLE" }, \
474 { FAULT_FLAG_TRIED, "TRIED" }, \
475 { FAULT_FLAG_USER, "USER" }, \
476 { FAULT_FLAG_REMOTE, "REMOTE" }, \
477 { FAULT_FLAG_INSTRUCTION, "INSTRUCTION" }, \
478 { FAULT_FLAG_INTERRUPTIBLE, "INTERRUPTIBLE" }
481 * vm_fault is filled by the the pagefault handler and passed to the vma's
482 * ->fault function. The vma's ->fault is responsible for returning a bitmask
483 * of VM_FAULT_xxx flags that give details about how the fault was handled.
485 * MM layer fills up gfp_mask for page allocations but fault handler might
486 * alter it if its implementation requires a different allocation context.
488 * pgoff should be used in favour of virtual_address, if possible.
491 struct vm_area_struct *vma; /* Target VMA */
492 unsigned int flags; /* FAULT_FLAG_xxx flags */
493 gfp_t gfp_mask; /* gfp mask to be used for allocations */
494 pgoff_t pgoff; /* Logical page offset based on vma */
495 unsigned long address; /* Faulting virtual address */
496 pmd_t *pmd; /* Pointer to pmd entry matching
498 pud_t *pud; /* Pointer to pud entry matching
501 pte_t orig_pte; /* Value of PTE at the time of fault */
503 struct page *cow_page; /* Page handler may use for COW fault */
504 struct mem_cgroup *memcg; /* Cgroup cow_page belongs to */
505 struct page *page; /* ->fault handlers should return a
506 * page here, unless VM_FAULT_NOPAGE
507 * is set (which is also implied by
510 /* These three entries are valid only while holding ptl lock */
511 pte_t *pte; /* Pointer to pte entry matching
512 * the 'address'. NULL if the page
513 * table hasn't been allocated.
515 spinlock_t *ptl; /* Page table lock.
516 * Protects pte page table if 'pte'
517 * is not NULL, otherwise pmd.
519 pgtable_t prealloc_pte; /* Pre-allocated pte page table.
520 * vm_ops->map_pages() calls
521 * alloc_set_pte() from atomic context.
522 * do_fault_around() pre-allocates
523 * page table to avoid allocation from
528 /* page entry size for vm->huge_fault() */
529 enum page_entry_size {
536 * These are the virtual MM functions - opening of an area, closing and
537 * unmapping it (needed to keep files on disk up-to-date etc), pointer
538 * to the functions called when a no-page or a wp-page exception occurs.
540 struct vm_operations_struct {
541 void (*open)(struct vm_area_struct * area);
542 void (*close)(struct vm_area_struct * area);
543 int (*split)(struct vm_area_struct * area, unsigned long addr);
544 int (*mremap)(struct vm_area_struct * area);
545 vm_fault_t (*fault)(struct vm_fault *vmf);
546 vm_fault_t (*huge_fault)(struct vm_fault *vmf,
547 enum page_entry_size pe_size);
548 void (*map_pages)(struct vm_fault *vmf,
549 pgoff_t start_pgoff, pgoff_t end_pgoff);
550 unsigned long (*pagesize)(struct vm_area_struct * area);
552 /* notification that a previously read-only page is about to become
553 * writable, if an error is returned it will cause a SIGBUS */
554 vm_fault_t (*page_mkwrite)(struct vm_fault *vmf);
556 /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */
557 vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf);
559 /* called by access_process_vm when get_user_pages() fails, typically
560 * for use by special VMAs that can switch between memory and hardware
562 int (*access)(struct vm_area_struct *vma, unsigned long addr,
563 void *buf, int len, int write);
565 /* Called by the /proc/PID/maps code to ask the vma whether it
566 * has a special name. Returning non-NULL will also cause this
567 * vma to be dumped unconditionally. */
568 const char *(*name)(struct vm_area_struct *vma);
572 * set_policy() op must add a reference to any non-NULL @new mempolicy
573 * to hold the policy upon return. Caller should pass NULL @new to
574 * remove a policy and fall back to surrounding context--i.e. do not
575 * install a MPOL_DEFAULT policy, nor the task or system default
578 int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
581 * get_policy() op must add reference [mpol_get()] to any policy at
582 * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure
583 * in mm/mempolicy.c will do this automatically.
584 * get_policy() must NOT add a ref if the policy at (vma,addr) is not
585 * marked as MPOL_SHARED. vma policies are protected by the mmap_sem.
586 * If no [shared/vma] mempolicy exists at the addr, get_policy() op
587 * must return NULL--i.e., do not "fallback" to task or system default
590 struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
594 * Called by vm_normal_page() for special PTEs to find the
595 * page for @addr. This is useful if the default behavior
596 * (using pte_page()) would not find the correct page.
598 struct page *(*find_special_page)(struct vm_area_struct *vma,
602 static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm)
604 static const struct vm_operations_struct dummy_vm_ops = {};
606 memset(vma, 0, sizeof(*vma));
608 vma->vm_ops = &dummy_vm_ops;
609 INIT_LIST_HEAD(&vma->anon_vma_chain);
612 static inline void vma_set_anonymous(struct vm_area_struct *vma)
617 static inline bool vma_is_anonymous(struct vm_area_struct *vma)
622 static inline bool vma_is_temporary_stack(struct vm_area_struct *vma)
624 int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP);
629 if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) ==
630 VM_STACK_INCOMPLETE_SETUP)
636 static inline bool vma_is_foreign(struct vm_area_struct *vma)
641 if (current->mm != vma->vm_mm)
647 static inline bool vma_is_accessible(struct vm_area_struct *vma)
649 return vma->vm_flags & VM_ACCESS_FLAGS;
654 * The vma_is_shmem is not inline because it is used only by slow
655 * paths in userfault.
657 bool vma_is_shmem(struct vm_area_struct *vma);
659 static inline bool vma_is_shmem(struct vm_area_struct *vma) { return false; }
662 int vma_is_stack_for_current(struct vm_area_struct *vma);
664 /* flush_tlb_range() takes a vma, not a mm, and can care about flags */
665 #define TLB_FLUSH_VMA(mm,flags) { .vm_mm = (mm), .vm_flags = (flags) }
671 * FIXME: take this include out, include page-flags.h in
672 * files which need it (119 of them)
674 #include <linux/page-flags.h>
675 #include <linux/huge_mm.h>
678 * Methods to modify the page usage count.
680 * What counts for a page usage:
681 * - cache mapping (page->mapping)
682 * - private data (page->private)
683 * - page mapped in a task's page tables, each mapping
684 * is counted separately
686 * Also, many kernel routines increase the page count before a critical
687 * routine so they can be sure the page doesn't go away from under them.
691 * Drop a ref, return true if the refcount fell to zero (the page has no users)
693 static inline int put_page_testzero(struct page *page)
695 VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
696 return page_ref_dec_and_test(page);
700 * Try to grab a ref unless the page has a refcount of zero, return false if
702 * This can be called when MMU is off so it must not access
703 * any of the virtual mappings.
705 static inline int get_page_unless_zero(struct page *page)
707 return page_ref_add_unless(page, 1, 0);
710 extern int page_is_ram(unsigned long pfn);
718 int region_intersects(resource_size_t offset, size_t size, unsigned long flags,
721 /* Support for virtually mapped pages */
722 struct page *vmalloc_to_page(const void *addr);
723 unsigned long vmalloc_to_pfn(const void *addr);
726 * Determine if an address is within the vmalloc range
728 * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
729 * is no special casing required.
732 #ifndef is_ioremap_addr
733 #define is_ioremap_addr(x) is_vmalloc_addr(x)
737 extern bool is_vmalloc_addr(const void *x);
738 extern int is_vmalloc_or_module_addr(const void *x);
740 static inline bool is_vmalloc_addr(const void *x)
744 static inline int is_vmalloc_or_module_addr(const void *x)
750 extern void *kvmalloc_node(size_t size, gfp_t flags, int node);
751 static inline void *kvmalloc(size_t size, gfp_t flags)
753 return kvmalloc_node(size, flags, NUMA_NO_NODE);
755 static inline void *kvzalloc_node(size_t size, gfp_t flags, int node)
757 return kvmalloc_node(size, flags | __GFP_ZERO, node);
759 static inline void *kvzalloc(size_t size, gfp_t flags)
761 return kvmalloc(size, flags | __GFP_ZERO);
764 static inline void *kvmalloc_array(size_t n, size_t size, gfp_t flags)
768 if (unlikely(check_mul_overflow(n, size, &bytes)))
771 return kvmalloc(bytes, flags);
774 static inline void *kvcalloc(size_t n, size_t size, gfp_t flags)
776 return kvmalloc_array(n, size, flags | __GFP_ZERO);
779 extern void kvfree(const void *addr);
782 * Mapcount of compound page as a whole, does not include mapped sub-pages.
784 * Must be called only for compound pages or any their tail sub-pages.
786 static inline int compound_mapcount(struct page *page)
788 VM_BUG_ON_PAGE(!PageCompound(page), page);
789 page = compound_head(page);
790 return atomic_read(compound_mapcount_ptr(page)) + 1;
794 * The atomic page->_mapcount, starts from -1: so that transitions
795 * both from it and to it can be tracked, using atomic_inc_and_test
796 * and atomic_add_negative(-1).
798 static inline void page_mapcount_reset(struct page *page)
800 atomic_set(&(page)->_mapcount, -1);
803 int __page_mapcount(struct page *page);
806 * Mapcount of 0-order page; when compound sub-page, includes
807 * compound_mapcount().
809 * Result is undefined for pages which cannot be mapped into userspace.
810 * For example SLAB or special types of pages. See function page_has_type().
811 * They use this place in struct page differently.
813 static inline int page_mapcount(struct page *page)
815 if (unlikely(PageCompound(page)))
816 return __page_mapcount(page);
817 return atomic_read(&page->_mapcount) + 1;
820 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
821 int total_mapcount(struct page *page);
822 int page_trans_huge_mapcount(struct page *page, int *total_mapcount);
824 static inline int total_mapcount(struct page *page)
826 return page_mapcount(page);
828 static inline int page_trans_huge_mapcount(struct page *page,
831 int mapcount = page_mapcount(page);
833 *total_mapcount = mapcount;
838 static inline struct page *virt_to_head_page(const void *x)
840 struct page *page = virt_to_page(x);
842 return compound_head(page);
845 void __put_page(struct page *page);
847 void put_pages_list(struct list_head *pages);
849 void split_page(struct page *page, unsigned int order);
852 * Compound pages have a destructor function. Provide a
853 * prototype for that function and accessor functions.
854 * These are _only_ valid on the head of a compound page.
856 typedef void compound_page_dtor(struct page *);
858 /* Keep the enum in sync with compound_page_dtors array in mm/page_alloc.c */
859 enum compound_dtor_id {
862 #ifdef CONFIG_HUGETLB_PAGE
865 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
870 extern compound_page_dtor * const compound_page_dtors[];
872 static inline void set_compound_page_dtor(struct page *page,
873 enum compound_dtor_id compound_dtor)
875 VM_BUG_ON_PAGE(compound_dtor >= NR_COMPOUND_DTORS, page);
876 page[1].compound_dtor = compound_dtor;
879 static inline compound_page_dtor *get_compound_page_dtor(struct page *page)
881 VM_BUG_ON_PAGE(page[1].compound_dtor >= NR_COMPOUND_DTORS, page);
882 return compound_page_dtors[page[1].compound_dtor];
885 static inline unsigned int compound_order(struct page *page)
889 return page[1].compound_order;
892 static inline bool hpage_pincount_available(struct page *page)
895 * Can the page->hpage_pinned_refcount field be used? That field is in
896 * the 3rd page of the compound page, so the smallest (2-page) compound
897 * pages cannot support it.
899 page = compound_head(page);
900 return PageCompound(page) && compound_order(page) > 1;
903 static inline int compound_pincount(struct page *page)
905 VM_BUG_ON_PAGE(!hpage_pincount_available(page), page);
906 page = compound_head(page);
907 return atomic_read(compound_pincount_ptr(page));
910 static inline void set_compound_order(struct page *page, unsigned int order)
912 page[1].compound_order = order;
915 /* Returns the number of pages in this potentially compound page. */
916 static inline unsigned long compound_nr(struct page *page)
918 return 1UL << compound_order(page);
921 /* Returns the number of bytes in this potentially compound page. */
922 static inline unsigned long page_size(struct page *page)
924 return PAGE_SIZE << compound_order(page);
927 /* Returns the number of bits needed for the number of bytes in a page */
928 static inline unsigned int page_shift(struct page *page)
930 return PAGE_SHIFT + compound_order(page);
933 void free_compound_page(struct page *page);
937 * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when
938 * servicing faults for write access. In the normal case, do always want
939 * pte_mkwrite. But get_user_pages can cause write faults for mappings
940 * that do not have writing enabled, when used by access_process_vm.
942 static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
944 if (likely(vma->vm_flags & VM_WRITE))
945 pte = pte_mkwrite(pte);
949 vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg,
951 vm_fault_t finish_fault(struct vm_fault *vmf);
952 vm_fault_t finish_mkwrite_fault(struct vm_fault *vmf);
956 * Multiple processes may "see" the same page. E.g. for untouched
957 * mappings of /dev/null, all processes see the same page full of
958 * zeroes, and text pages of executables and shared libraries have
959 * only one copy in memory, at most, normally.
961 * For the non-reserved pages, page_count(page) denotes a reference count.
962 * page_count() == 0 means the page is free. page->lru is then used for
963 * freelist management in the buddy allocator.
964 * page_count() > 0 means the page has been allocated.
966 * Pages are allocated by the slab allocator in order to provide memory
967 * to kmalloc and kmem_cache_alloc. In this case, the management of the
968 * page, and the fields in 'struct page' are the responsibility of mm/slab.c
969 * unless a particular usage is carefully commented. (the responsibility of
970 * freeing the kmalloc memory is the caller's, of course).
972 * A page may be used by anyone else who does a __get_free_page().
973 * In this case, page_count still tracks the references, and should only
974 * be used through the normal accessor functions. The top bits of page->flags
975 * and page->virtual store page management information, but all other fields
976 * are unused and could be used privately, carefully. The management of this
977 * page is the responsibility of the one who allocated it, and those who have
978 * subsequently been given references to it.
980 * The other pages (we may call them "pagecache pages") are completely
981 * managed by the Linux memory manager: I/O, buffers, swapping etc.
982 * The following discussion applies only to them.
984 * A pagecache page contains an opaque `private' member, which belongs to the
985 * page's address_space. Usually, this is the address of a circular list of
986 * the page's disk buffers. PG_private must be set to tell the VM to call
987 * into the filesystem to release these pages.
989 * A page may belong to an inode's memory mapping. In this case, page->mapping
990 * is the pointer to the inode, and page->index is the file offset of the page,
991 * in units of PAGE_SIZE.
993 * If pagecache pages are not associated with an inode, they are said to be
994 * anonymous pages. These may become associated with the swapcache, and in that
995 * case PG_swapcache is set, and page->private is an offset into the swapcache.
997 * In either case (swapcache or inode backed), the pagecache itself holds one
998 * reference to the page. Setting PG_private should also increment the
999 * refcount. The each user mapping also has a reference to the page.
1001 * The pagecache pages are stored in a per-mapping radix tree, which is
1002 * rooted at mapping->i_pages, and indexed by offset.
1003 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
1004 * lists, we instead now tag pages as dirty/writeback in the radix tree.
1006 * All pagecache pages may be subject to I/O:
1007 * - inode pages may need to be read from disk,
1008 * - inode pages which have been modified and are MAP_SHARED may need
1009 * to be written back to the inode on disk,
1010 * - anonymous pages (including MAP_PRIVATE file mappings) which have been
1011 * modified may need to be swapped out to swap space and (later) to be read
1016 * The zone field is never updated after free_area_init_core()
1017 * sets it, so none of the operations on it need to be atomic.
1020 /* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_CPUPID] | ... | FLAGS | */
1021 #define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH)
1022 #define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH)
1023 #define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH)
1024 #define LAST_CPUPID_PGOFF (ZONES_PGOFF - LAST_CPUPID_WIDTH)
1025 #define KASAN_TAG_PGOFF (LAST_CPUPID_PGOFF - KASAN_TAG_WIDTH)
1028 * Define the bit shifts to access each section. For non-existent
1029 * sections we define the shift as 0; that plus a 0 mask ensures
1030 * the compiler will optimise away reference to them.
1032 #define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0))
1033 #define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0))
1034 #define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0))
1035 #define LAST_CPUPID_PGSHIFT (LAST_CPUPID_PGOFF * (LAST_CPUPID_WIDTH != 0))
1036 #define KASAN_TAG_PGSHIFT (KASAN_TAG_PGOFF * (KASAN_TAG_WIDTH != 0))
1038 /* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */
1039 #ifdef NODE_NOT_IN_PAGE_FLAGS
1040 #define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT)
1041 #define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \
1042 SECTIONS_PGOFF : ZONES_PGOFF)
1044 #define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT)
1045 #define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \
1046 NODES_PGOFF : ZONES_PGOFF)
1049 #define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0))
1051 #define ZONES_MASK ((1UL << ZONES_WIDTH) - 1)
1052 #define NODES_MASK ((1UL << NODES_WIDTH) - 1)
1053 #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1)
1054 #define LAST_CPUPID_MASK ((1UL << LAST_CPUPID_SHIFT) - 1)
1055 #define KASAN_TAG_MASK ((1UL << KASAN_TAG_WIDTH) - 1)
1056 #define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1)
1058 static inline enum zone_type page_zonenum(const struct page *page)
1060 return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;
1063 #ifdef CONFIG_ZONE_DEVICE
1064 static inline bool is_zone_device_page(const struct page *page)
1066 return page_zonenum(page) == ZONE_DEVICE;
1068 extern void memmap_init_zone_device(struct zone *, unsigned long,
1069 unsigned long, struct dev_pagemap *);
1071 static inline bool is_zone_device_page(const struct page *page)
1077 #ifdef CONFIG_DEV_PAGEMAP_OPS
1078 void free_devmap_managed_page(struct page *page);
1079 DECLARE_STATIC_KEY_FALSE(devmap_managed_key);
1081 static inline bool page_is_devmap_managed(struct page *page)
1083 if (!static_branch_unlikely(&devmap_managed_key))
1085 if (!is_zone_device_page(page))
1087 switch (page->pgmap->type) {
1088 case MEMORY_DEVICE_PRIVATE:
1089 case MEMORY_DEVICE_FS_DAX:
1097 void put_devmap_managed_page(struct page *page);
1099 #else /* CONFIG_DEV_PAGEMAP_OPS */
1100 static inline bool page_is_devmap_managed(struct page *page)
1105 static inline void put_devmap_managed_page(struct page *page)
1108 #endif /* CONFIG_DEV_PAGEMAP_OPS */
1110 static inline bool is_device_private_page(const struct page *page)
1112 return IS_ENABLED(CONFIG_DEV_PAGEMAP_OPS) &&
1113 IS_ENABLED(CONFIG_DEVICE_PRIVATE) &&
1114 is_zone_device_page(page) &&
1115 page->pgmap->type == MEMORY_DEVICE_PRIVATE;
1118 static inline bool is_pci_p2pdma_page(const struct page *page)
1120 return IS_ENABLED(CONFIG_DEV_PAGEMAP_OPS) &&
1121 IS_ENABLED(CONFIG_PCI_P2PDMA) &&
1122 is_zone_device_page(page) &&
1123 page->pgmap->type == MEMORY_DEVICE_PCI_P2PDMA;
1126 /* 127: arbitrary random number, small enough to assemble well */
1127 #define page_ref_zero_or_close_to_overflow(page) \
1128 ((unsigned int) page_ref_count(page) + 127u <= 127u)
1130 static inline void get_page(struct page *page)
1132 page = compound_head(page);
1134 * Getting a normal page or the head of a compound page
1135 * requires to already have an elevated page->_refcount.
1137 VM_BUG_ON_PAGE(page_ref_zero_or_close_to_overflow(page), page);
1141 bool __must_check try_grab_page(struct page *page, unsigned int flags);
1143 static inline __must_check bool try_get_page(struct page *page)
1145 page = compound_head(page);
1146 if (WARN_ON_ONCE(page_ref_count(page) <= 0))
1152 static inline void put_page(struct page *page)
1154 page = compound_head(page);
1157 * For devmap managed pages we need to catch refcount transition from
1158 * 2 to 1, when refcount reach one it means the page is free and we
1159 * need to inform the device driver through callback. See
1160 * include/linux/memremap.h and HMM for details.
1162 if (page_is_devmap_managed(page)) {
1163 put_devmap_managed_page(page);
1167 if (put_page_testzero(page))
1172 * GUP_PIN_COUNTING_BIAS, and the associated functions that use it, overload
1173 * the page's refcount so that two separate items are tracked: the original page
1174 * reference count, and also a new count of how many pin_user_pages() calls were
1175 * made against the page. ("gup-pinned" is another term for the latter).
1177 * With this scheme, pin_user_pages() becomes special: such pages are marked as
1178 * distinct from normal pages. As such, the unpin_user_page() call (and its
1179 * variants) must be used in order to release gup-pinned pages.
1183 * By making GUP_PIN_COUNTING_BIAS a power of two, debugging of page reference
1184 * counts with respect to pin_user_pages() and unpin_user_page() becomes
1185 * simpler, due to the fact that adding an even power of two to the page
1186 * refcount has the effect of using only the upper N bits, for the code that
1187 * counts up using the bias value. This means that the lower bits are left for
1188 * the exclusive use of the original code that increments and decrements by one
1189 * (or at least, by much smaller values than the bias value).
1191 * Of course, once the lower bits overflow into the upper bits (and this is
1192 * OK, because subtraction recovers the original values), then visual inspection
1193 * no longer suffices to directly view the separate counts. However, for normal
1194 * applications that don't have huge page reference counts, this won't be an
1197 * Locking: the lockless algorithm described in page_cache_get_speculative()
1198 * and page_cache_gup_pin_speculative() provides safe operation for
1199 * get_user_pages and page_mkclean and other calls that race to set up page
1202 #define GUP_PIN_COUNTING_BIAS (1U << 10)
1204 void unpin_user_page(struct page *page);
1205 void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages,
1207 void unpin_user_pages(struct page **pages, unsigned long npages);
1210 * page_maybe_dma_pinned() - report if a page is pinned for DMA.
1212 * This function checks if a page has been pinned via a call to
1213 * pin_user_pages*().
1215 * For non-huge pages, the return value is partially fuzzy: false is not fuzzy,
1216 * because it means "definitely not pinned for DMA", but true means "probably
1217 * pinned for DMA, but possibly a false positive due to having at least
1218 * GUP_PIN_COUNTING_BIAS worth of normal page references".
1220 * False positives are OK, because: a) it's unlikely for a page to get that many
1221 * refcounts, and b) all the callers of this routine are expected to be able to
1222 * deal gracefully with a false positive.
1224 * For huge pages, the result will be exactly correct. That's because we have
1225 * more tracking data available: the 3rd struct page in the compound page is
1226 * used to track the pincount (instead using of the GUP_PIN_COUNTING_BIAS
1229 * For more information, please see Documentation/core-api/pin_user_pages.rst.
1231 * @page: pointer to page to be queried.
1232 * @Return: True, if it is likely that the page has been "dma-pinned".
1233 * False, if the page is definitely not dma-pinned.
1235 static inline bool page_maybe_dma_pinned(struct page *page)
1237 if (hpage_pincount_available(page))
1238 return compound_pincount(page) > 0;
1241 * page_ref_count() is signed. If that refcount overflows, then
1242 * page_ref_count() returns a negative value, and callers will avoid
1243 * further incrementing the refcount.
1245 * Here, for that overflow case, use the signed bit to count a little
1246 * bit higher via unsigned math, and thus still get an accurate result.
1248 return ((unsigned int)page_ref_count(compound_head(page))) >=
1249 GUP_PIN_COUNTING_BIAS;
1252 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
1253 #define SECTION_IN_PAGE_FLAGS
1257 * The identification function is mainly used by the buddy allocator for
1258 * determining if two pages could be buddies. We are not really identifying
1259 * the zone since we could be using the section number id if we do not have
1260 * node id available in page flags.
1261 * We only guarantee that it will return the same value for two combinable
1264 static inline int page_zone_id(struct page *page)
1266 return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK;
1269 #ifdef NODE_NOT_IN_PAGE_FLAGS
1270 extern int page_to_nid(const struct page *page);
1272 static inline int page_to_nid(const struct page *page)
1274 struct page *p = (struct page *)page;
1276 return (PF_POISONED_CHECK(p)->flags >> NODES_PGSHIFT) & NODES_MASK;
1280 #ifdef CONFIG_NUMA_BALANCING
1281 static inline int cpu_pid_to_cpupid(int cpu, int pid)
1283 return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK);
1286 static inline int cpupid_to_pid(int cpupid)
1288 return cpupid & LAST__PID_MASK;
1291 static inline int cpupid_to_cpu(int cpupid)
1293 return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK;
1296 static inline int cpupid_to_nid(int cpupid)
1298 return cpu_to_node(cpupid_to_cpu(cpupid));
1301 static inline bool cpupid_pid_unset(int cpupid)
1303 return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK);
1306 static inline bool cpupid_cpu_unset(int cpupid)
1308 return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK);
1311 static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid)
1313 return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid);
1316 #define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid)
1317 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
1318 static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1320 return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK);
1323 static inline int page_cpupid_last(struct page *page)
1325 return page->_last_cpupid;
1327 static inline void page_cpupid_reset_last(struct page *page)
1329 page->_last_cpupid = -1 & LAST_CPUPID_MASK;
1332 static inline int page_cpupid_last(struct page *page)
1334 return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
1337 extern int page_cpupid_xchg_last(struct page *page, int cpupid);
1339 static inline void page_cpupid_reset_last(struct page *page)
1341 page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT;
1343 #endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
1344 #else /* !CONFIG_NUMA_BALANCING */
1345 static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1347 return page_to_nid(page); /* XXX */
1350 static inline int page_cpupid_last(struct page *page)
1352 return page_to_nid(page); /* XXX */
1355 static inline int cpupid_to_nid(int cpupid)
1360 static inline int cpupid_to_pid(int cpupid)
1365 static inline int cpupid_to_cpu(int cpupid)
1370 static inline int cpu_pid_to_cpupid(int nid, int pid)
1375 static inline bool cpupid_pid_unset(int cpupid)
1380 static inline void page_cpupid_reset_last(struct page *page)
1384 static inline bool cpupid_match_pid(struct task_struct *task, int cpupid)
1388 #endif /* CONFIG_NUMA_BALANCING */
1390 #ifdef CONFIG_KASAN_SW_TAGS
1391 static inline u8 page_kasan_tag(const struct page *page)
1393 return (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK;
1396 static inline void page_kasan_tag_set(struct page *page, u8 tag)
1398 page->flags &= ~(KASAN_TAG_MASK << KASAN_TAG_PGSHIFT);
1399 page->flags |= (tag & KASAN_TAG_MASK) << KASAN_TAG_PGSHIFT;
1402 static inline void page_kasan_tag_reset(struct page *page)
1404 page_kasan_tag_set(page, 0xff);
1407 static inline u8 page_kasan_tag(const struct page *page)
1412 static inline void page_kasan_tag_set(struct page *page, u8 tag) { }
1413 static inline void page_kasan_tag_reset(struct page *page) { }
1416 static inline struct zone *page_zone(const struct page *page)
1418 return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
1421 static inline pg_data_t *page_pgdat(const struct page *page)
1423 return NODE_DATA(page_to_nid(page));
1426 #ifdef SECTION_IN_PAGE_FLAGS
1427 static inline void set_page_section(struct page *page, unsigned long section)
1429 page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
1430 page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
1433 static inline unsigned long page_to_section(const struct page *page)
1435 return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
1439 static inline void set_page_zone(struct page *page, enum zone_type zone)
1441 page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
1442 page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
1445 static inline void set_page_node(struct page *page, unsigned long node)
1447 page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
1448 page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
1451 static inline void set_page_links(struct page *page, enum zone_type zone,
1452 unsigned long node, unsigned long pfn)
1454 set_page_zone(page, zone);
1455 set_page_node(page, node);
1456 #ifdef SECTION_IN_PAGE_FLAGS
1457 set_page_section(page, pfn_to_section_nr(pfn));
1462 static inline struct mem_cgroup *page_memcg(struct page *page)
1464 return page->mem_cgroup;
1466 static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
1468 WARN_ON_ONCE(!rcu_read_lock_held());
1469 return READ_ONCE(page->mem_cgroup);
1472 static inline struct mem_cgroup *page_memcg(struct page *page)
1476 static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
1478 WARN_ON_ONCE(!rcu_read_lock_held());
1484 * Some inline functions in vmstat.h depend on page_zone()
1486 #include <linux/vmstat.h>
1488 static __always_inline void *lowmem_page_address(const struct page *page)
1490 return page_to_virt(page);
1493 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
1494 #define HASHED_PAGE_VIRTUAL
1497 #if defined(WANT_PAGE_VIRTUAL)
1498 static inline void *page_address(const struct page *page)
1500 return page->virtual;
1502 static inline void set_page_address(struct page *page, void *address)
1504 page->virtual = address;
1506 #define page_address_init() do { } while(0)
1509 #if defined(HASHED_PAGE_VIRTUAL)
1510 void *page_address(const struct page *page);
1511 void set_page_address(struct page *page, void *virtual);
1512 void page_address_init(void);
1515 #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
1516 #define page_address(page) lowmem_page_address(page)
1517 #define set_page_address(page, address) do { } while(0)
1518 #define page_address_init() do { } while(0)
1521 extern void *page_rmapping(struct page *page);
1522 extern struct anon_vma *page_anon_vma(struct page *page);
1523 extern struct address_space *page_mapping(struct page *page);
1525 extern struct address_space *__page_file_mapping(struct page *);
1528 struct address_space *page_file_mapping(struct page *page)
1530 if (unlikely(PageSwapCache(page)))
1531 return __page_file_mapping(page);
1533 return page->mapping;
1536 extern pgoff_t __page_file_index(struct page *page);
1539 * Return the pagecache index of the passed page. Regular pagecache pages
1540 * use ->index whereas swapcache pages use swp_offset(->private)
1542 static inline pgoff_t page_index(struct page *page)
1544 if (unlikely(PageSwapCache(page)))
1545 return __page_file_index(page);
1549 bool page_mapped(struct page *page);
1550 struct address_space *page_mapping(struct page *page);
1551 struct address_space *page_mapping_file(struct page *page);
1554 * Return true only if the page has been allocated with
1555 * ALLOC_NO_WATERMARKS and the low watermark was not
1556 * met implying that the system is under some pressure.
1558 static inline bool page_is_pfmemalloc(struct page *page)
1561 * Page index cannot be this large so this must be
1562 * a pfmemalloc page.
1564 return page->index == -1UL;
1568 * Only to be called by the page allocator on a freshly allocated
1571 static inline void set_page_pfmemalloc(struct page *page)
1576 static inline void clear_page_pfmemalloc(struct page *page)
1582 * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
1584 extern void pagefault_out_of_memory(void);
1586 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
1589 * Flags passed to show_mem() and show_free_areas() to suppress output in
1592 #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */
1594 extern void show_free_areas(unsigned int flags, nodemask_t *nodemask);
1597 extern bool can_do_mlock(void);
1599 static inline bool can_do_mlock(void) { return false; }
1601 extern int user_shm_lock(size_t, struct user_struct *);
1602 extern void user_shm_unlock(size_t, struct user_struct *);
1605 * Parameter block passed down to zap_pte_range in exceptional cases.
1607 struct zap_details {
1608 struct address_space *check_mapping; /* Check page->mapping if set */
1609 pgoff_t first_index; /* Lowest page->index to unmap */
1610 pgoff_t last_index; /* Highest page->index to unmap */
1613 struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
1615 struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
1618 void zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
1619 unsigned long size);
1620 void zap_page_range(struct vm_area_struct *vma, unsigned long address,
1621 unsigned long size);
1622 void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
1623 unsigned long start, unsigned long end);
1625 struct mmu_notifier_range;
1627 void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
1628 unsigned long end, unsigned long floor, unsigned long ceiling);
1629 int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
1630 struct vm_area_struct *vma);
1631 int follow_pte_pmd(struct mm_struct *mm, unsigned long address,
1632 struct mmu_notifier_range *range,
1633 pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp);
1634 int follow_pfn(struct vm_area_struct *vma, unsigned long address,
1635 unsigned long *pfn);
1636 int follow_phys(struct vm_area_struct *vma, unsigned long address,
1637 unsigned int flags, unsigned long *prot, resource_size_t *phys);
1638 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
1639 void *buf, int len, int write);
1641 extern void truncate_pagecache(struct inode *inode, loff_t new);
1642 extern void truncate_setsize(struct inode *inode, loff_t newsize);
1643 void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
1644 void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
1645 int truncate_inode_page(struct address_space *mapping, struct page *page);
1646 int generic_error_remove_page(struct address_space *mapping, struct page *page);
1647 int invalidate_inode_page(struct page *page);
1650 extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
1651 unsigned long address, unsigned int flags);
1652 extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
1653 unsigned long address, unsigned int fault_flags,
1655 void unmap_mapping_pages(struct address_space *mapping,
1656 pgoff_t start, pgoff_t nr, bool even_cows);
1657 void unmap_mapping_range(struct address_space *mapping,
1658 loff_t const holebegin, loff_t const holelen, int even_cows);
1660 static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
1661 unsigned long address, unsigned int flags)
1663 /* should never happen if there's no MMU */
1665 return VM_FAULT_SIGBUS;
1667 static inline int fixup_user_fault(struct task_struct *tsk,
1668 struct mm_struct *mm, unsigned long address,
1669 unsigned int fault_flags, bool *unlocked)
1671 /* should never happen if there's no MMU */
1675 static inline void unmap_mapping_pages(struct address_space *mapping,
1676 pgoff_t start, pgoff_t nr, bool even_cows) { }
1677 static inline void unmap_mapping_range(struct address_space *mapping,
1678 loff_t const holebegin, loff_t const holelen, int even_cows) { }
1681 static inline void unmap_shared_mapping_range(struct address_space *mapping,
1682 loff_t const holebegin, loff_t const holelen)
1684 unmap_mapping_range(mapping, holebegin, holelen, 0);
1687 extern int access_process_vm(struct task_struct *tsk, unsigned long addr,
1688 void *buf, int len, unsigned int gup_flags);
1689 extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
1690 void *buf, int len, unsigned int gup_flags);
1691 extern int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm,
1692 unsigned long addr, void *buf, int len, unsigned int gup_flags);
1694 long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
1695 unsigned long start, unsigned long nr_pages,
1696 unsigned int gup_flags, struct page **pages,
1697 struct vm_area_struct **vmas, int *locked);
1698 long pin_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,
1699 unsigned long start, unsigned long nr_pages,
1700 unsigned int gup_flags, struct page **pages,
1701 struct vm_area_struct **vmas, int *locked);
1702 long get_user_pages(unsigned long start, unsigned long nr_pages,
1703 unsigned int gup_flags, struct page **pages,
1704 struct vm_area_struct **vmas);
1705 long pin_user_pages(unsigned long start, unsigned long nr_pages,
1706 unsigned int gup_flags, struct page **pages,
1707 struct vm_area_struct **vmas);
1708 long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
1709 unsigned int gup_flags, struct page **pages, int *locked);
1710 long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
1711 struct page **pages, unsigned int gup_flags);
1713 int get_user_pages_fast(unsigned long start, int nr_pages,
1714 unsigned int gup_flags, struct page **pages);
1715 int pin_user_pages_fast(unsigned long start, int nr_pages,
1716 unsigned int gup_flags, struct page **pages);
1718 int account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc);
1719 int __account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc,
1720 struct task_struct *task, bool bypass_rlim);
1722 /* Container for pinned pfns / pages */
1723 struct frame_vector {
1724 unsigned int nr_allocated; /* Number of frames we have space for */
1725 unsigned int nr_frames; /* Number of frames stored in ptrs array */
1726 bool got_ref; /* Did we pin pages by getting page ref? */
1727 bool is_pfns; /* Does array contain pages or pfns? */
1728 void *ptrs[0]; /* Array of pinned pfns / pages. Use
1729 * pfns_vector_pages() or pfns_vector_pfns()
1733 struct frame_vector *frame_vector_create(unsigned int nr_frames);
1734 void frame_vector_destroy(struct frame_vector *vec);
1735 int get_vaddr_frames(unsigned long start, unsigned int nr_pfns,
1736 unsigned int gup_flags, struct frame_vector *vec);
1737 void put_vaddr_frames(struct frame_vector *vec);
1738 int frame_vector_to_pages(struct frame_vector *vec);
1739 void frame_vector_to_pfns(struct frame_vector *vec);
1741 static inline unsigned int frame_vector_count(struct frame_vector *vec)
1743 return vec->nr_frames;
1746 static inline struct page **frame_vector_pages(struct frame_vector *vec)
1749 int err = frame_vector_to_pages(vec);
1752 return ERR_PTR(err);
1754 return (struct page **)(vec->ptrs);
1757 static inline unsigned long *frame_vector_pfns(struct frame_vector *vec)
1760 frame_vector_to_pfns(vec);
1761 return (unsigned long *)(vec->ptrs);
1765 int get_kernel_pages(const struct kvec *iov, int nr_pages, int write,
1766 struct page **pages);
1767 int get_kernel_page(unsigned long start, int write, struct page **pages);
1768 struct page *get_dump_page(unsigned long addr);
1770 extern int try_to_release_page(struct page * page, gfp_t gfp_mask);
1771 extern void do_invalidatepage(struct page *page, unsigned int offset,
1772 unsigned int length);
1774 void __set_page_dirty(struct page *, struct address_space *, int warn);
1775 int __set_page_dirty_nobuffers(struct page *page);
1776 int __set_page_dirty_no_writeback(struct page *page);
1777 int redirty_page_for_writepage(struct writeback_control *wbc,
1779 void account_page_dirtied(struct page *page, struct address_space *mapping);
1780 void account_page_cleaned(struct page *page, struct address_space *mapping,
1781 struct bdi_writeback *wb);
1782 int set_page_dirty(struct page *page);
1783 int set_page_dirty_lock(struct page *page);
1784 void __cancel_dirty_page(struct page *page);
1785 static inline void cancel_dirty_page(struct page *page)
1787 /* Avoid atomic ops, locking, etc. when not actually needed. */
1788 if (PageDirty(page))
1789 __cancel_dirty_page(page);
1791 int clear_page_dirty_for_io(struct page *page);
1793 int get_cmdline(struct task_struct *task, char *buffer, int buflen);
1795 extern unsigned long move_page_tables(struct vm_area_struct *vma,
1796 unsigned long old_addr, struct vm_area_struct *new_vma,
1797 unsigned long new_addr, unsigned long len,
1798 bool need_rmap_locks);
1801 * Flags used by change_protection(). For now we make it a bitmap so
1802 * that we can pass in multiple flags just like parameters. However
1803 * for now all the callers are only use one of the flags at the same
1806 /* Whether we should allow dirty bit accounting */
1807 #define MM_CP_DIRTY_ACCT (1UL << 0)
1808 /* Whether this protection change is for NUMA hints */
1809 #define MM_CP_PROT_NUMA (1UL << 1)
1810 /* Whether this change is for write protecting */
1811 #define MM_CP_UFFD_WP (1UL << 2) /* do wp */
1812 #define MM_CP_UFFD_WP_RESOLVE (1UL << 3) /* Resolve wp */
1813 #define MM_CP_UFFD_WP_ALL (MM_CP_UFFD_WP | \
1814 MM_CP_UFFD_WP_RESOLVE)
1816 extern unsigned long change_protection(struct vm_area_struct *vma, unsigned long start,
1817 unsigned long end, pgprot_t newprot,
1818 unsigned long cp_flags);
1819 extern int mprotect_fixup(struct vm_area_struct *vma,
1820 struct vm_area_struct **pprev, unsigned long start,
1821 unsigned long end, unsigned long newflags);
1824 * doesn't attempt to fault and will return short.
1826 int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
1827 struct page **pages);
1829 * per-process(per-mm_struct) statistics.
1831 static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
1833 long val = atomic_long_read(&mm->rss_stat.count[member]);
1835 #ifdef SPLIT_RSS_COUNTING
1837 * counter is updated in asynchronous manner and may go to minus.
1838 * But it's never be expected number for users.
1843 return (unsigned long)val;
1846 void mm_trace_rss_stat(struct mm_struct *mm, int member, long count);
1848 static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
1850 long count = atomic_long_add_return(value, &mm->rss_stat.count[member]);
1852 mm_trace_rss_stat(mm, member, count);
1855 static inline void inc_mm_counter(struct mm_struct *mm, int member)
1857 long count = atomic_long_inc_return(&mm->rss_stat.count[member]);
1859 mm_trace_rss_stat(mm, member, count);
1862 static inline void dec_mm_counter(struct mm_struct *mm, int member)
1864 long count = atomic_long_dec_return(&mm->rss_stat.count[member]);
1866 mm_trace_rss_stat(mm, member, count);
1869 /* Optimized variant when page is already known not to be PageAnon */
1870 static inline int mm_counter_file(struct page *page)
1872 if (PageSwapBacked(page))
1873 return MM_SHMEMPAGES;
1874 return MM_FILEPAGES;
1877 static inline int mm_counter(struct page *page)
1880 return MM_ANONPAGES;
1881 return mm_counter_file(page);
1884 static inline unsigned long get_mm_rss(struct mm_struct *mm)
1886 return get_mm_counter(mm, MM_FILEPAGES) +
1887 get_mm_counter(mm, MM_ANONPAGES) +
1888 get_mm_counter(mm, MM_SHMEMPAGES);
1891 static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
1893 return max(mm->hiwater_rss, get_mm_rss(mm));
1896 static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
1898 return max(mm->hiwater_vm, mm->total_vm);
1901 static inline void update_hiwater_rss(struct mm_struct *mm)
1903 unsigned long _rss = get_mm_rss(mm);
1905 if ((mm)->hiwater_rss < _rss)
1906 (mm)->hiwater_rss = _rss;
1909 static inline void update_hiwater_vm(struct mm_struct *mm)
1911 if (mm->hiwater_vm < mm->total_vm)
1912 mm->hiwater_vm = mm->total_vm;
1915 static inline void reset_mm_hiwater_rss(struct mm_struct *mm)
1917 mm->hiwater_rss = get_mm_rss(mm);
1920 static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
1921 struct mm_struct *mm)
1923 unsigned long hiwater_rss = get_mm_hiwater_rss(mm);
1925 if (*maxrss < hiwater_rss)
1926 *maxrss = hiwater_rss;
1929 #if defined(SPLIT_RSS_COUNTING)
1930 void sync_mm_rss(struct mm_struct *mm);
1932 static inline void sync_mm_rss(struct mm_struct *mm)
1937 #ifndef CONFIG_ARCH_HAS_PTE_SPECIAL
1938 static inline int pte_special(pte_t pte)
1943 static inline pte_t pte_mkspecial(pte_t pte)
1949 #ifndef CONFIG_ARCH_HAS_PTE_DEVMAP
1950 static inline int pte_devmap(pte_t pte)
1956 int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot);
1958 extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
1960 static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
1964 __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl));
1968 #ifdef __PAGETABLE_P4D_FOLDED
1969 static inline int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
1970 unsigned long address)
1975 int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
1978 #if defined(__PAGETABLE_PUD_FOLDED) || !defined(CONFIG_MMU)
1979 static inline int __pud_alloc(struct mm_struct *mm, p4d_t *p4d,
1980 unsigned long address)
1984 static inline void mm_inc_nr_puds(struct mm_struct *mm) {}
1985 static inline void mm_dec_nr_puds(struct mm_struct *mm) {}
1988 int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address);
1990 static inline void mm_inc_nr_puds(struct mm_struct *mm)
1992 if (mm_pud_folded(mm))
1994 atomic_long_add(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
1997 static inline void mm_dec_nr_puds(struct mm_struct *mm)
1999 if (mm_pud_folded(mm))
2001 atomic_long_sub(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
2005 #if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU)
2006 static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
2007 unsigned long address)
2012 static inline void mm_inc_nr_pmds(struct mm_struct *mm) {}
2013 static inline void mm_dec_nr_pmds(struct mm_struct *mm) {}
2016 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
2018 static inline void mm_inc_nr_pmds(struct mm_struct *mm)
2020 if (mm_pmd_folded(mm))
2022 atomic_long_add(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2025 static inline void mm_dec_nr_pmds(struct mm_struct *mm)
2027 if (mm_pmd_folded(mm))
2029 atomic_long_sub(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2034 static inline void mm_pgtables_bytes_init(struct mm_struct *mm)
2036 atomic_long_set(&mm->pgtables_bytes, 0);
2039 static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2041 return atomic_long_read(&mm->pgtables_bytes);
2044 static inline void mm_inc_nr_ptes(struct mm_struct *mm)
2046 atomic_long_add(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2049 static inline void mm_dec_nr_ptes(struct mm_struct *mm)
2051 atomic_long_sub(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2055 static inline void mm_pgtables_bytes_init(struct mm_struct *mm) {}
2056 static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2061 static inline void mm_inc_nr_ptes(struct mm_struct *mm) {}
2062 static inline void mm_dec_nr_ptes(struct mm_struct *mm) {}
2065 int __pte_alloc(struct mm_struct *mm, pmd_t *pmd);
2066 int __pte_alloc_kernel(pmd_t *pmd);
2068 #if defined(CONFIG_MMU)
2071 * The following ifdef needed to get the 5level-fixup.h header to work.
2072 * Remove it when 5level-fixup.h has been removed.
2074 #ifndef __ARCH_HAS_5LEVEL_HACK
2075 static inline p4d_t *p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
2076 unsigned long address)
2078 return (unlikely(pgd_none(*pgd)) && __p4d_alloc(mm, pgd, address)) ?
2079 NULL : p4d_offset(pgd, address);
2082 static inline pud_t *pud_alloc(struct mm_struct *mm, p4d_t *p4d,
2083 unsigned long address)
2085 return (unlikely(p4d_none(*p4d)) && __pud_alloc(mm, p4d, address)) ?
2086 NULL : pud_offset(p4d, address);
2088 #endif /* !__ARCH_HAS_5LEVEL_HACK */
2090 static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
2092 return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
2093 NULL: pmd_offset(pud, address);
2095 #endif /* CONFIG_MMU */
2097 #if USE_SPLIT_PTE_PTLOCKS
2098 #if ALLOC_SPLIT_PTLOCKS
2099 void __init ptlock_cache_init(void);
2100 extern bool ptlock_alloc(struct page *page);
2101 extern void ptlock_free(struct page *page);
2103 static inline spinlock_t *ptlock_ptr(struct page *page)
2107 #else /* ALLOC_SPLIT_PTLOCKS */
2108 static inline void ptlock_cache_init(void)
2112 static inline bool ptlock_alloc(struct page *page)
2117 static inline void ptlock_free(struct page *page)
2121 static inline spinlock_t *ptlock_ptr(struct page *page)
2125 #endif /* ALLOC_SPLIT_PTLOCKS */
2127 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2129 return ptlock_ptr(pmd_page(*pmd));
2132 static inline bool ptlock_init(struct page *page)
2135 * prep_new_page() initialize page->private (and therefore page->ptl)
2136 * with 0. Make sure nobody took it in use in between.
2138 * It can happen if arch try to use slab for page table allocation:
2139 * slab code uses page->slab_cache, which share storage with page->ptl.
2141 VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page);
2142 if (!ptlock_alloc(page))
2144 spin_lock_init(ptlock_ptr(page));
2148 #else /* !USE_SPLIT_PTE_PTLOCKS */
2150 * We use mm->page_table_lock to guard all pagetable pages of the mm.
2152 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2154 return &mm->page_table_lock;
2156 static inline void ptlock_cache_init(void) {}
2157 static inline bool ptlock_init(struct page *page) { return true; }
2158 static inline void ptlock_free(struct page *page) {}
2159 #endif /* USE_SPLIT_PTE_PTLOCKS */
2161 static inline void pgtable_init(void)
2163 ptlock_cache_init();
2164 pgtable_cache_init();
2167 static inline bool pgtable_pte_page_ctor(struct page *page)
2169 if (!ptlock_init(page))
2171 __SetPageTable(page);
2172 inc_zone_page_state(page, NR_PAGETABLE);
2176 static inline void pgtable_pte_page_dtor(struct page *page)
2179 __ClearPageTable(page);
2180 dec_zone_page_state(page, NR_PAGETABLE);
2183 #define pte_offset_map_lock(mm, pmd, address, ptlp) \
2185 spinlock_t *__ptl = pte_lockptr(mm, pmd); \
2186 pte_t *__pte = pte_offset_map(pmd, address); \
2192 #define pte_unmap_unlock(pte, ptl) do { \
2197 #define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd))
2199 #define pte_alloc_map(mm, pmd, address) \
2200 (pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address))
2202 #define pte_alloc_map_lock(mm, pmd, address, ptlp) \
2203 (pte_alloc(mm, pmd) ? \
2204 NULL : pte_offset_map_lock(mm, pmd, address, ptlp))
2206 #define pte_alloc_kernel(pmd, address) \
2207 ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \
2208 NULL: pte_offset_kernel(pmd, address))
2210 #if USE_SPLIT_PMD_PTLOCKS
2212 static struct page *pmd_to_page(pmd_t *pmd)
2214 unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
2215 return virt_to_page((void *)((unsigned long) pmd & mask));
2218 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
2220 return ptlock_ptr(pmd_to_page(pmd));
2223 static inline bool pgtable_pmd_page_ctor(struct page *page)
2225 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2226 page->pmd_huge_pte = NULL;
2228 return ptlock_init(page);
2231 static inline void pgtable_pmd_page_dtor(struct page *page)
2233 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2234 VM_BUG_ON_PAGE(page->pmd_huge_pte, page);
2239 #define pmd_huge_pte(mm, pmd) (pmd_to_page(pmd)->pmd_huge_pte)
2243 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
2245 return &mm->page_table_lock;
2248 static inline bool pgtable_pmd_page_ctor(struct page *page) { return true; }
2249 static inline void pgtable_pmd_page_dtor(struct page *page) {}
2251 #define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte)
2255 static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd)
2257 spinlock_t *ptl = pmd_lockptr(mm, pmd);
2263 * No scalability reason to split PUD locks yet, but follow the same pattern
2264 * as the PMD locks to make it easier if we decide to. The VM should not be
2265 * considered ready to switch to split PUD locks yet; there may be places
2266 * which need to be converted from page_table_lock.
2268 static inline spinlock_t *pud_lockptr(struct mm_struct *mm, pud_t *pud)
2270 return &mm->page_table_lock;
2273 static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud)
2275 spinlock_t *ptl = pud_lockptr(mm, pud);
2281 extern void __init pagecache_init(void);
2282 extern void free_area_init(unsigned long * zones_size);
2283 extern void __init free_area_init_node(int nid, unsigned long * zones_size,
2284 unsigned long zone_start_pfn, unsigned long *zholes_size);
2285 extern void free_initmem(void);
2288 * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
2289 * into the buddy system. The freed pages will be poisoned with pattern
2290 * "poison" if it's within range [0, UCHAR_MAX].
2291 * Return pages freed into the buddy system.
2293 extern unsigned long free_reserved_area(void *start, void *end,
2294 int poison, const char *s);
2296 #ifdef CONFIG_HIGHMEM
2298 * Free a highmem page into the buddy system, adjusting totalhigh_pages
2299 * and totalram_pages.
2301 extern void free_highmem_page(struct page *page);
2304 extern void adjust_managed_page_count(struct page *page, long count);
2305 extern void mem_init_print_info(const char *str);
2307 extern void reserve_bootmem_region(phys_addr_t start, phys_addr_t end);
2309 /* Free the reserved page into the buddy system, so it gets managed. */
2310 static inline void __free_reserved_page(struct page *page)
2312 ClearPageReserved(page);
2313 init_page_count(page);
2317 static inline void free_reserved_page(struct page *page)
2319 __free_reserved_page(page);
2320 adjust_managed_page_count(page, 1);
2323 static inline void mark_page_reserved(struct page *page)
2325 SetPageReserved(page);
2326 adjust_managed_page_count(page, -1);
2330 * Default method to free all the __init memory into the buddy system.
2331 * The freed pages will be poisoned with pattern "poison" if it's within
2332 * range [0, UCHAR_MAX].
2333 * Return pages freed into the buddy system.
2335 static inline unsigned long free_initmem_default(int poison)
2337 extern char __init_begin[], __init_end[];
2339 return free_reserved_area(&__init_begin, &__init_end,
2340 poison, "unused kernel");
2343 static inline unsigned long get_num_physpages(void)
2346 unsigned long phys_pages = 0;
2348 for_each_online_node(nid)
2349 phys_pages += node_present_pages(nid);
2354 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
2356 * With CONFIG_HAVE_MEMBLOCK_NODE_MAP set, an architecture may initialise its
2357 * zones, allocate the backing mem_map and account for memory holes in a more
2358 * architecture independent manner. This is a substitute for creating the
2359 * zone_sizes[] and zholes_size[] arrays and passing them to
2360 * free_area_init_node()
2362 * An architecture is expected to register range of page frames backed by
2363 * physical memory with memblock_add[_node]() before calling
2364 * free_area_init_nodes() passing in the PFN each zone ends at. At a basic
2365 * usage, an architecture is expected to do something like
2367 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
2369 * for_each_valid_physical_page_range()
2370 * memblock_add_node(base, size, nid)
2371 * free_area_init_nodes(max_zone_pfns);
2373 * free_bootmem_with_active_regions() calls free_bootmem_node() for each
2374 * registered physical page range. Similarly
2375 * sparse_memory_present_with_active_regions() calls memory_present() for
2376 * each range when SPARSEMEM is enabled.
2378 * See mm/page_alloc.c for more information on each function exposed by
2379 * CONFIG_HAVE_MEMBLOCK_NODE_MAP.
2381 extern void free_area_init_nodes(unsigned long *max_zone_pfn);
2382 unsigned long node_map_pfn_alignment(void);
2383 unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn,
2384 unsigned long end_pfn);
2385 extern unsigned long absent_pages_in_range(unsigned long start_pfn,
2386 unsigned long end_pfn);
2387 extern void get_pfn_range_for_nid(unsigned int nid,
2388 unsigned long *start_pfn, unsigned long *end_pfn);
2389 extern unsigned long find_min_pfn_with_active_regions(void);
2390 extern void free_bootmem_with_active_regions(int nid,
2391 unsigned long max_low_pfn);
2392 extern void sparse_memory_present_with_active_regions(int nid);
2394 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
2396 #if !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) && \
2397 !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID)
2398 static inline int __early_pfn_to_nid(unsigned long pfn,
2399 struct mminit_pfnnid_cache *state)
2404 /* please see mm/page_alloc.c */
2405 extern int __meminit early_pfn_to_nid(unsigned long pfn);
2406 /* there is a per-arch backend function. */
2407 extern int __meminit __early_pfn_to_nid(unsigned long pfn,
2408 struct mminit_pfnnid_cache *state);
2411 extern void set_dma_reserve(unsigned long new_dma_reserve);
2412 extern void memmap_init_zone(unsigned long, int, unsigned long, unsigned long,
2413 enum memmap_context, struct vmem_altmap *);
2414 extern void setup_per_zone_wmarks(void);
2415 extern int __meminit init_per_zone_wmark_min(void);
2416 extern void mem_init(void);
2417 extern void __init mmap_init(void);
2418 extern void show_mem(unsigned int flags, nodemask_t *nodemask);
2419 extern long si_mem_available(void);
2420 extern void si_meminfo(struct sysinfo * val);
2421 extern void si_meminfo_node(struct sysinfo *val, int nid);
2422 #ifdef __HAVE_ARCH_RESERVED_KERNEL_PAGES
2423 extern unsigned long arch_reserved_kernel_pages(void);
2426 extern __printf(3, 4)
2427 void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...);
2429 extern void setup_per_cpu_pageset(void);
2432 extern int min_free_kbytes;
2433 extern int watermark_boost_factor;
2434 extern int watermark_scale_factor;
2437 extern atomic_long_t mmap_pages_allocated;
2438 extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
2440 /* interval_tree.c */
2441 void vma_interval_tree_insert(struct vm_area_struct *node,
2442 struct rb_root_cached *root);
2443 void vma_interval_tree_insert_after(struct vm_area_struct *node,
2444 struct vm_area_struct *prev,
2445 struct rb_root_cached *root);
2446 void vma_interval_tree_remove(struct vm_area_struct *node,
2447 struct rb_root_cached *root);
2448 struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root_cached *root,
2449 unsigned long start, unsigned long last);
2450 struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
2451 unsigned long start, unsigned long last);
2453 #define vma_interval_tree_foreach(vma, root, start, last) \
2454 for (vma = vma_interval_tree_iter_first(root, start, last); \
2455 vma; vma = vma_interval_tree_iter_next(vma, start, last))
2457 void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
2458 struct rb_root_cached *root);
2459 void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
2460 struct rb_root_cached *root);
2461 struct anon_vma_chain *
2462 anon_vma_interval_tree_iter_first(struct rb_root_cached *root,
2463 unsigned long start, unsigned long last);
2464 struct anon_vma_chain *anon_vma_interval_tree_iter_next(
2465 struct anon_vma_chain *node, unsigned long start, unsigned long last);
2466 #ifdef CONFIG_DEBUG_VM_RB
2467 void anon_vma_interval_tree_verify(struct anon_vma_chain *node);
2470 #define anon_vma_interval_tree_foreach(avc, root, start, last) \
2471 for (avc = anon_vma_interval_tree_iter_first(root, start, last); \
2472 avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))
2475 extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin);
2476 extern int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
2477 unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert,
2478 struct vm_area_struct *expand);
2479 static inline int vma_adjust(struct vm_area_struct *vma, unsigned long start,
2480 unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert)
2482 return __vma_adjust(vma, start, end, pgoff, insert, NULL);
2484 extern struct vm_area_struct *vma_merge(struct mm_struct *,
2485 struct vm_area_struct *prev, unsigned long addr, unsigned long end,
2486 unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t,
2487 struct mempolicy *, struct vm_userfaultfd_ctx);
2488 extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
2489 extern int __split_vma(struct mm_struct *, struct vm_area_struct *,
2490 unsigned long addr, int new_below);
2491 extern int split_vma(struct mm_struct *, struct vm_area_struct *,
2492 unsigned long addr, int new_below);
2493 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
2494 extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *,
2495 struct rb_node **, struct rb_node *);
2496 extern void unlink_file_vma(struct vm_area_struct *);
2497 extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
2498 unsigned long addr, unsigned long len, pgoff_t pgoff,
2499 bool *need_rmap_locks);
2500 extern void exit_mmap(struct mm_struct *);
2502 static inline int check_data_rlimit(unsigned long rlim,
2504 unsigned long start,
2505 unsigned long end_data,
2506 unsigned long start_data)
2508 if (rlim < RLIM_INFINITY) {
2509 if (((new - start) + (end_data - start_data)) > rlim)
2516 extern int mm_take_all_locks(struct mm_struct *mm);
2517 extern void mm_drop_all_locks(struct mm_struct *mm);
2519 extern void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
2520 extern struct file *get_mm_exe_file(struct mm_struct *mm);
2521 extern struct file *get_task_exe_file(struct task_struct *task);
2523 extern bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long npages);
2524 extern void vm_stat_account(struct mm_struct *, vm_flags_t, long npages);
2526 extern bool vma_is_special_mapping(const struct vm_area_struct *vma,
2527 const struct vm_special_mapping *sm);
2528 extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm,
2529 unsigned long addr, unsigned long len,
2530 unsigned long flags,
2531 const struct vm_special_mapping *spec);
2532 /* This is an obsolete alternative to _install_special_mapping. */
2533 extern int install_special_mapping(struct mm_struct *mm,
2534 unsigned long addr, unsigned long len,
2535 unsigned long flags, struct page **pages);
2537 unsigned long randomize_stack_top(unsigned long stack_top);
2539 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
2541 extern unsigned long mmap_region(struct file *file, unsigned long addr,
2542 unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
2543 struct list_head *uf);
2544 extern unsigned long do_mmap(struct file *file, unsigned long addr,
2545 unsigned long len, unsigned long prot, unsigned long flags,
2546 vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate,
2547 struct list_head *uf);
2548 extern int __do_munmap(struct mm_struct *, unsigned long, size_t,
2549 struct list_head *uf, bool downgrade);
2550 extern int do_munmap(struct mm_struct *, unsigned long, size_t,
2551 struct list_head *uf);
2552 extern int do_madvise(unsigned long start, size_t len_in, int behavior);
2554 static inline unsigned long
2555 do_mmap_pgoff(struct file *file, unsigned long addr,
2556 unsigned long len, unsigned long prot, unsigned long flags,
2557 unsigned long pgoff, unsigned long *populate,
2558 struct list_head *uf)
2560 return do_mmap(file, addr, len, prot, flags, 0, pgoff, populate, uf);
2564 extern int __mm_populate(unsigned long addr, unsigned long len,
2566 static inline void mm_populate(unsigned long addr, unsigned long len)
2569 (void) __mm_populate(addr, len, 1);
2572 static inline void mm_populate(unsigned long addr, unsigned long len) {}
2575 /* These take the mm semaphore themselves */
2576 extern int __must_check vm_brk(unsigned long, unsigned long);
2577 extern int __must_check vm_brk_flags(unsigned long, unsigned long, unsigned long);
2578 extern int vm_munmap(unsigned long, size_t);
2579 extern unsigned long __must_check vm_mmap(struct file *, unsigned long,
2580 unsigned long, unsigned long,
2581 unsigned long, unsigned long);
2583 struct vm_unmapped_area_info {
2584 #define VM_UNMAPPED_AREA_TOPDOWN 1
2585 unsigned long flags;
2586 unsigned long length;
2587 unsigned long low_limit;
2588 unsigned long high_limit;
2589 unsigned long align_mask;
2590 unsigned long align_offset;
2593 extern unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info);
2596 extern void truncate_inode_pages(struct address_space *, loff_t);
2597 extern void truncate_inode_pages_range(struct address_space *,
2598 loff_t lstart, loff_t lend);
2599 extern void truncate_inode_pages_final(struct address_space *);
2601 /* generic vm_area_ops exported for stackable file systems */
2602 extern vm_fault_t filemap_fault(struct vm_fault *vmf);
2603 extern void filemap_map_pages(struct vm_fault *vmf,
2604 pgoff_t start_pgoff, pgoff_t end_pgoff);
2605 extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf);
2607 /* mm/page-writeback.c */
2608 int __must_check write_one_page(struct page *page);
2609 void task_dirty_inc(struct task_struct *tsk);
2612 #define VM_READAHEAD_PAGES (SZ_128K / PAGE_SIZE)
2614 int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
2615 pgoff_t offset, unsigned long nr_to_read);
2617 void page_cache_sync_readahead(struct address_space *mapping,
2618 struct file_ra_state *ra,
2621 unsigned long size);
2623 void page_cache_async_readahead(struct address_space *mapping,
2624 struct file_ra_state *ra,
2628 unsigned long size);
2630 extern unsigned long stack_guard_gap;
2631 /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
2632 extern int expand_stack(struct vm_area_struct *vma, unsigned long address);
2634 /* CONFIG_STACK_GROWSUP still needs to to grow downwards at some places */
2635 extern int expand_downwards(struct vm_area_struct *vma,
2636 unsigned long address);
2638 extern int expand_upwards(struct vm_area_struct *vma, unsigned long address);
2640 #define expand_upwards(vma, address) (0)
2643 /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */
2644 extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
2645 extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
2646 struct vm_area_struct **pprev);
2648 /* Look up the first VMA which intersects the interval start_addr..end_addr-1,
2649 NULL if none. Assume start_addr < end_addr. */
2650 static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr)
2652 struct vm_area_struct * vma = find_vma(mm,start_addr);
2654 if (vma && end_addr <= vma->vm_start)
2659 static inline unsigned long vm_start_gap(struct vm_area_struct *vma)
2661 unsigned long vm_start = vma->vm_start;
2663 if (vma->vm_flags & VM_GROWSDOWN) {
2664 vm_start -= stack_guard_gap;
2665 if (vm_start > vma->vm_start)
2671 static inline unsigned long vm_end_gap(struct vm_area_struct *vma)
2673 unsigned long vm_end = vma->vm_end;
2675 if (vma->vm_flags & VM_GROWSUP) {
2676 vm_end += stack_guard_gap;
2677 if (vm_end < vma->vm_end)
2678 vm_end = -PAGE_SIZE;
2683 static inline unsigned long vma_pages(struct vm_area_struct *vma)
2685 return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
2688 /* Look up the first VMA which exactly match the interval vm_start ... vm_end */
2689 static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
2690 unsigned long vm_start, unsigned long vm_end)
2692 struct vm_area_struct *vma = find_vma(mm, vm_start);
2694 if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
2700 static inline bool range_in_vma(struct vm_area_struct *vma,
2701 unsigned long start, unsigned long end)
2703 return (vma && vma->vm_start <= start && end <= vma->vm_end);
2707 pgprot_t vm_get_page_prot(unsigned long vm_flags);
2708 void vma_set_page_prot(struct vm_area_struct *vma);
2710 static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
2714 static inline void vma_set_page_prot(struct vm_area_struct *vma)
2716 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
2720 #ifdef CONFIG_NUMA_BALANCING
2721 unsigned long change_prot_numa(struct vm_area_struct *vma,
2722 unsigned long start, unsigned long end);
2725 struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr);
2726 int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
2727 unsigned long pfn, unsigned long size, pgprot_t);
2728 int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
2729 int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr,
2730 struct page **pages, unsigned long *num);
2731 int vm_map_pages(struct vm_area_struct *vma, struct page **pages,
2733 int vm_map_pages_zero(struct vm_area_struct *vma, struct page **pages,
2735 vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
2737 vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
2738 unsigned long pfn, pgprot_t pgprot);
2739 vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
2741 vm_fault_t vmf_insert_mixed_prot(struct vm_area_struct *vma, unsigned long addr,
2742 pfn_t pfn, pgprot_t pgprot);
2743 vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
2744 unsigned long addr, pfn_t pfn);
2745 int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
2747 static inline vm_fault_t vmf_insert_page(struct vm_area_struct *vma,
2748 unsigned long addr, struct page *page)
2750 int err = vm_insert_page(vma, addr, page);
2753 return VM_FAULT_OOM;
2754 if (err < 0 && err != -EBUSY)
2755 return VM_FAULT_SIGBUS;
2757 return VM_FAULT_NOPAGE;
2760 static inline vm_fault_t vmf_error(int err)
2763 return VM_FAULT_OOM;
2764 return VM_FAULT_SIGBUS;
2767 struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
2768 unsigned int foll_flags);
2770 #define FOLL_WRITE 0x01 /* check pte is writable */
2771 #define FOLL_TOUCH 0x02 /* mark page accessed */
2772 #define FOLL_GET 0x04 /* do get_page on page */
2773 #define FOLL_DUMP 0x08 /* give error on hole if it would be zero */
2774 #define FOLL_FORCE 0x10 /* get_user_pages read/write w/o permission */
2775 #define FOLL_NOWAIT 0x20 /* if a disk transfer is needed, start the IO
2776 * and return without waiting upon it */
2777 #define FOLL_POPULATE 0x40 /* fault in page */
2778 #define FOLL_SPLIT 0x80 /* don't return transhuge pages, split them */
2779 #define FOLL_HWPOISON 0x100 /* check page is hwpoisoned */
2780 #define FOLL_NUMA 0x200 /* force NUMA hinting page fault */
2781 #define FOLL_MIGRATION 0x400 /* wait for page to replace migration entry */
2782 #define FOLL_TRIED 0x800 /* a retry, previous pass started an IO */
2783 #define FOLL_MLOCK 0x1000 /* lock present pages */
2784 #define FOLL_REMOTE 0x2000 /* we are working on non-current tsk/mm */
2785 #define FOLL_COW 0x4000 /* internal GUP flag */
2786 #define FOLL_ANON 0x8000 /* don't do file mappings */
2787 #define FOLL_LONGTERM 0x10000 /* mapping lifetime is indefinite: see below */
2788 #define FOLL_SPLIT_PMD 0x20000 /* split huge pmd before returning */
2789 #define FOLL_PIN 0x40000 /* pages must be released via unpin_user_page */
2792 * FOLL_PIN and FOLL_LONGTERM may be used in various combinations with each
2793 * other. Here is what they mean, and how to use them:
2795 * FOLL_LONGTERM indicates that the page will be held for an indefinite time
2796 * period _often_ under userspace control. This is in contrast to
2797 * iov_iter_get_pages(), whose usages are transient.
2799 * FIXME: For pages which are part of a filesystem, mappings are subject to the
2800 * lifetime enforced by the filesystem and we need guarantees that longterm
2801 * users like RDMA and V4L2 only establish mappings which coordinate usage with
2802 * the filesystem. Ideas for this coordination include revoking the longterm
2803 * pin, delaying writeback, bounce buffer page writeback, etc. As FS DAX was
2804 * added after the problem with filesystems was found FS DAX VMAs are
2805 * specifically failed. Filesystem pages are still subject to bugs and use of
2806 * FOLL_LONGTERM should be avoided on those pages.
2808 * FIXME: Also NOTE that FOLL_LONGTERM is not supported in every GUP call.
2809 * Currently only get_user_pages() and get_user_pages_fast() support this flag
2810 * and calls to get_user_pages_[un]locked are specifically not allowed. This
2811 * is due to an incompatibility with the FS DAX check and
2812 * FAULT_FLAG_ALLOW_RETRY.
2814 * In the CMA case: long term pins in a CMA region would unnecessarily fragment
2815 * that region. And so, CMA attempts to migrate the page before pinning, when
2816 * FOLL_LONGTERM is specified.
2818 * FOLL_PIN indicates that a special kind of tracking (not just page->_refcount,
2819 * but an additional pin counting system) will be invoked. This is intended for
2820 * anything that gets a page reference and then touches page data (for example,
2821 * Direct IO). This lets the filesystem know that some non-file-system entity is
2822 * potentially changing the pages' data. In contrast to FOLL_GET (whose pages
2823 * are released via put_page()), FOLL_PIN pages must be released, ultimately, by
2824 * a call to unpin_user_page().
2826 * FOLL_PIN is similar to FOLL_GET: both of these pin pages. They use different
2827 * and separate refcounting mechanisms, however, and that means that each has
2828 * its own acquire and release mechanisms:
2830 * FOLL_GET: get_user_pages*() to acquire, and put_page() to release.
2832 * FOLL_PIN: pin_user_pages*() to acquire, and unpin_user_pages to release.
2834 * FOLL_PIN and FOLL_GET are mutually exclusive for a given function call.
2835 * (The underlying pages may experience both FOLL_GET-based and FOLL_PIN-based
2836 * calls applied to them, and that's perfectly OK. This is a constraint on the
2837 * callers, not on the pages.)
2839 * FOLL_PIN should be set internally by the pin_user_pages*() APIs, never
2840 * directly by the caller. That's in order to help avoid mismatches when
2841 * releasing pages: get_user_pages*() pages must be released via put_page(),
2842 * while pin_user_pages*() pages must be released via unpin_user_page().
2844 * Please see Documentation/core-api/pin_user_pages.rst for more information.
2847 static inline int vm_fault_to_errno(vm_fault_t vm_fault, int foll_flags)
2849 if (vm_fault & VM_FAULT_OOM)
2851 if (vm_fault & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE))
2852 return (foll_flags & FOLL_HWPOISON) ? -EHWPOISON : -EFAULT;
2853 if (vm_fault & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV))
2858 typedef int (*pte_fn_t)(pte_t *pte, unsigned long addr, void *data);
2859 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
2860 unsigned long size, pte_fn_t fn, void *data);
2861 extern int apply_to_existing_page_range(struct mm_struct *mm,
2862 unsigned long address, unsigned long size,
2863 pte_fn_t fn, void *data);
2865 #ifdef CONFIG_PAGE_POISONING
2866 extern bool page_poisoning_enabled(void);
2867 extern void kernel_poison_pages(struct page *page, int numpages, int enable);
2869 static inline bool page_poisoning_enabled(void) { return false; }
2870 static inline void kernel_poison_pages(struct page *page, int numpages,
2874 #ifdef CONFIG_INIT_ON_ALLOC_DEFAULT_ON
2875 DECLARE_STATIC_KEY_TRUE(init_on_alloc);
2877 DECLARE_STATIC_KEY_FALSE(init_on_alloc);
2879 static inline bool want_init_on_alloc(gfp_t flags)
2881 if (static_branch_unlikely(&init_on_alloc) &&
2882 !page_poisoning_enabled())
2884 return flags & __GFP_ZERO;
2887 #ifdef CONFIG_INIT_ON_FREE_DEFAULT_ON
2888 DECLARE_STATIC_KEY_TRUE(init_on_free);
2890 DECLARE_STATIC_KEY_FALSE(init_on_free);
2892 static inline bool want_init_on_free(void)
2894 return static_branch_unlikely(&init_on_free) &&
2895 !page_poisoning_enabled();
2898 #ifdef CONFIG_DEBUG_PAGEALLOC
2899 extern void init_debug_pagealloc(void);
2901 static inline void init_debug_pagealloc(void) {}
2903 extern bool _debug_pagealloc_enabled_early;
2904 DECLARE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
2906 static inline bool debug_pagealloc_enabled(void)
2908 return IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) &&
2909 _debug_pagealloc_enabled_early;
2913 * For use in fast paths after init_debug_pagealloc() has run, or when a
2914 * false negative result is not harmful when called too early.
2916 static inline bool debug_pagealloc_enabled_static(void)
2918 if (!IS_ENABLED(CONFIG_DEBUG_PAGEALLOC))
2921 return static_branch_unlikely(&_debug_pagealloc_enabled);
2924 #if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_ARCH_HAS_SET_DIRECT_MAP)
2925 extern void __kernel_map_pages(struct page *page, int numpages, int enable);
2928 * When called in DEBUG_PAGEALLOC context, the call should most likely be
2929 * guarded by debug_pagealloc_enabled() or debug_pagealloc_enabled_static()
2932 kernel_map_pages(struct page *page, int numpages, int enable)
2934 __kernel_map_pages(page, numpages, enable);
2936 #ifdef CONFIG_HIBERNATION
2937 extern bool kernel_page_present(struct page *page);
2938 #endif /* CONFIG_HIBERNATION */
2939 #else /* CONFIG_DEBUG_PAGEALLOC || CONFIG_ARCH_HAS_SET_DIRECT_MAP */
2941 kernel_map_pages(struct page *page, int numpages, int enable) {}
2942 #ifdef CONFIG_HIBERNATION
2943 static inline bool kernel_page_present(struct page *page) { return true; }
2944 #endif /* CONFIG_HIBERNATION */
2945 #endif /* CONFIG_DEBUG_PAGEALLOC || CONFIG_ARCH_HAS_SET_DIRECT_MAP */
2947 #ifdef __HAVE_ARCH_GATE_AREA
2948 extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
2949 extern int in_gate_area_no_mm(unsigned long addr);
2950 extern int in_gate_area(struct mm_struct *mm, unsigned long addr);
2952 static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
2956 static inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
2957 static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
2961 #endif /* __HAVE_ARCH_GATE_AREA */
2963 extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm);
2965 #ifdef CONFIG_SYSCTL
2966 extern int sysctl_drop_caches;
2967 int drop_caches_sysctl_handler(struct ctl_table *, int,
2968 void __user *, size_t *, loff_t *);
2971 void drop_slab(void);
2972 void drop_slab_node(int nid);
2975 #define randomize_va_space 0
2977 extern int randomize_va_space;
2980 const char * arch_vma_name(struct vm_area_struct *vma);
2982 void print_vma_addr(char *prefix, unsigned long rip);
2984 static inline void print_vma_addr(char *prefix, unsigned long rip)
2989 void *sparse_buffer_alloc(unsigned long size);
2990 struct page * __populate_section_memmap(unsigned long pfn,
2991 unsigned long nr_pages, int nid, struct vmem_altmap *altmap);
2992 pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
2993 p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node);
2994 pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node);
2995 pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
2996 pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node);
2997 void *vmemmap_alloc_block(unsigned long size, int node);
2999 void *vmemmap_alloc_block_buf(unsigned long size, int node);
3000 void *altmap_alloc_block_buf(unsigned long size, struct vmem_altmap *altmap);
3001 void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
3002 int vmemmap_populate_basepages(unsigned long start, unsigned long end,
3004 int vmemmap_populate(unsigned long start, unsigned long end, int node,
3005 struct vmem_altmap *altmap);
3006 void vmemmap_populate_print_last(void);
3007 #ifdef CONFIG_MEMORY_HOTPLUG
3008 void vmemmap_free(unsigned long start, unsigned long end,
3009 struct vmem_altmap *altmap);
3011 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
3012 unsigned long nr_pages);
3015 MF_COUNT_INCREASED = 1 << 0,
3016 MF_ACTION_REQUIRED = 1 << 1,
3017 MF_MUST_KILL = 1 << 2,
3018 MF_SOFT_OFFLINE = 1 << 3,
3020 extern int memory_failure(unsigned long pfn, int flags);
3021 extern void memory_failure_queue(unsigned long pfn, int flags);
3022 extern int unpoison_memory(unsigned long pfn);
3023 extern int get_hwpoison_page(struct page *page);
3024 #define put_hwpoison_page(page) put_page(page)
3025 extern int sysctl_memory_failure_early_kill;
3026 extern int sysctl_memory_failure_recovery;
3027 extern void shake_page(struct page *p, int access);
3028 extern atomic_long_t num_poisoned_pages __read_mostly;
3029 extern int soft_offline_page(unsigned long pfn, int flags);
3033 * Error handlers for various types of pages.
3036 MF_IGNORED, /* Error: cannot be handled */
3037 MF_FAILED, /* Error: handling failed */
3038 MF_DELAYED, /* Will be handled later */
3039 MF_RECOVERED, /* Successfully recovered */
3042 enum mf_action_page_type {
3044 MF_MSG_KERNEL_HIGH_ORDER,
3046 MF_MSG_DIFFERENT_COMPOUND,
3047 MF_MSG_POISONED_HUGE,
3050 MF_MSG_NON_PMD_HUGE,
3051 MF_MSG_UNMAP_FAILED,
3052 MF_MSG_DIRTY_SWAPCACHE,
3053 MF_MSG_CLEAN_SWAPCACHE,
3054 MF_MSG_DIRTY_MLOCKED_LRU,
3055 MF_MSG_CLEAN_MLOCKED_LRU,
3056 MF_MSG_DIRTY_UNEVICTABLE_LRU,
3057 MF_MSG_CLEAN_UNEVICTABLE_LRU,
3060 MF_MSG_TRUNCATED_LRU,
3067 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
3068 extern void clear_huge_page(struct page *page,
3069 unsigned long addr_hint,
3070 unsigned int pages_per_huge_page);
3071 extern void copy_user_huge_page(struct page *dst, struct page *src,
3072 unsigned long addr_hint,
3073 struct vm_area_struct *vma,
3074 unsigned int pages_per_huge_page);
3075 extern long copy_huge_page_from_user(struct page *dst_page,
3076 const void __user *usr_src,
3077 unsigned int pages_per_huge_page,
3078 bool allow_pagefault);
3081 * vma_is_special_huge - Are transhuge page-table entries considered special?
3082 * @vma: Pointer to the struct vm_area_struct to consider
3084 * Whether transhuge page-table entries are considered "special" following
3085 * the definition in vm_normal_page().
3087 * Return: true if transhuge page-table entries should be considered special,
3090 static inline bool vma_is_special_huge(const struct vm_area_struct *vma)
3092 return vma_is_dax(vma) || (vma->vm_file &&
3093 (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)));
3096 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
3098 #ifdef CONFIG_DEBUG_PAGEALLOC
3099 extern unsigned int _debug_guardpage_minorder;
3100 DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
3102 static inline unsigned int debug_guardpage_minorder(void)
3104 return _debug_guardpage_minorder;
3107 static inline bool debug_guardpage_enabled(void)
3109 return static_branch_unlikely(&_debug_guardpage_enabled);
3112 static inline bool page_is_guard(struct page *page)
3114 if (!debug_guardpage_enabled())
3117 return PageGuard(page);
3120 static inline unsigned int debug_guardpage_minorder(void) { return 0; }
3121 static inline bool debug_guardpage_enabled(void) { return false; }
3122 static inline bool page_is_guard(struct page *page) { return false; }
3123 #endif /* CONFIG_DEBUG_PAGEALLOC */
3125 #if MAX_NUMNODES > 1
3126 void __init setup_nr_node_ids(void);
3128 static inline void setup_nr_node_ids(void) {}
3131 extern int memcmp_pages(struct page *page1, struct page *page2);
3133 static inline int pages_identical(struct page *page1, struct page *page2)
3135 return !memcmp_pages(page1, page2);
3138 #ifdef CONFIG_MAPPING_DIRTY_HELPERS
3139 unsigned long clean_record_shared_mapping_range(struct address_space *mapping,
3140 pgoff_t first_index, pgoff_t nr,
3141 pgoff_t bitmap_pgoff,
3142 unsigned long *bitmap,
3146 unsigned long wp_shared_mapping_range(struct address_space *mapping,
3147 pgoff_t first_index, pgoff_t nr);
3150 #endif /* __KERNEL__ */
3151 #endif /* _LINUX_MM_H */