1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef _LINUX_MM_H 3#define _LINUX_MM_H 4 5#include <linux/errno.h> 6#include <linux/mmdebug.h> 7#include <linux/gfp.h> 8#include <linux/bug.h> 9#include <linux/list.h> 10#include <linux/mmzone.h> 11#include <linux/rbtree.h> 12#include <linux/atomic.h> 13#include <linux/debug_locks.h> 14#include <linux/mm_types.h> 15#include <linux/mmap_lock.h> 16#include <linux/range.h> 17#include <linux/pfn.h> 18#include <linux/percpu-refcount.h> 19#include <linux/bit_spinlock.h> 20#include <linux/shrinker.h> 21#include <linux/resource.h> 22#include <linux/page_ext.h> 23#include <linux/err.h> 24#include <linux/page-flags.h> 25#include <linux/page_ref.h> 26#include <linux/overflow.h> 27#include <linux/sizes.h> 28#include <linux/sched.h> 29#include <linux/pgtable.h> 30#include <linux/kasan.h> 31#include <linux/memremap.h> 32#include <linux/slab.h> 33 34struct mempolicy; 35struct anon_vma; 36struct anon_vma_chain; 37struct user_struct; 38struct pt_regs; 39struct folio_batch; 40 41extern int sysctl_page_lock_unfairness; 42 43void mm_core_init(void); 44void init_mm_internals(void); 45 46#ifndef CONFIG_NUMA /* Don't use mapnrs, do it properly */ 47extern unsigned long max_mapnr; 48 49static inline void set_max_mapnr(unsigned long limit) 50{ 51 max_mapnr = limit; 52} 53#else 54static inline void set_max_mapnr(unsigned long limit) { } 55#endif 56 57extern atomic_long_t _totalram_pages; 58static inline unsigned long totalram_pages(void) 59{ 60 return (unsigned long)atomic_long_read(&_totalram_pages); 61} 62 63static inline void totalram_pages_inc(void) 64{ 65 atomic_long_inc(&_totalram_pages); 66} 67 68static inline void totalram_pages_dec(void) 69{ 70 atomic_long_dec(&_totalram_pages); 71} 72 73static inline void totalram_pages_add(long count) 74{ 75 atomic_long_add(count, &_totalram_pages); 76} 77 78extern void * high_memory; 79extern int page_cluster; 80extern const int page_cluster_max; 81 82#ifdef CONFIG_SYSCTL 83extern int sysctl_legacy_va_layout; 84#else 85#define sysctl_legacy_va_layout 0 86#endif 87 88#ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS 89extern const int mmap_rnd_bits_min; 90extern int mmap_rnd_bits_max __ro_after_init; 91extern int mmap_rnd_bits __read_mostly; 92#endif 93#ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS 94extern const int mmap_rnd_compat_bits_min; 95extern const int mmap_rnd_compat_bits_max; 96extern int mmap_rnd_compat_bits __read_mostly; 97#endif 98 99#include <asm/page.h> 100#include <asm/processor.h> 101 102#ifndef __pa_symbol 103#define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0)) 104#endif 105 106#ifndef page_to_virt 107#define page_to_virt(x) __va(PFN_PHYS(page_to_pfn(x))) 108#endif 109 110#ifndef lm_alias 111#define lm_alias(x) __va(__pa_symbol(x)) 112#endif 113 114/* 115 * To prevent common memory management code establishing 116 * a zero page mapping on a read fault. 117 * This macro should be defined within <asm/pgtable.h>. 118 * s390 does this to prevent multiplexing of hardware bits 119 * related to the physical page in case of virtualization. 120 */ 121#ifndef mm_forbids_zeropage 122#define mm_forbids_zeropage(X) (0) 123#endif 124 125/* 126 * On some architectures it is expensive to call memset() for small sizes. 127 * If an architecture decides to implement their own version of 128 * mm_zero_struct_page they should wrap the defines below in a #ifndef and 129 * define their own version of this macro in <asm/pgtable.h> 130 */ 131#if BITS_PER_LONG == 64 132/* This function must be updated when the size of struct page grows above 96 133 * or reduces below 56. The idea that compiler optimizes out switch() 134 * statement, and only leaves move/store instructions. Also the compiler can 135 * combine write statements if they are both assignments and can be reordered, 136 * this can result in several of the writes here being dropped. 137 */ 138#define mm_zero_struct_page(pp) __mm_zero_struct_page(pp) 139static inline void __mm_zero_struct_page(struct page *page) 140{ 141 unsigned long *_pp = (void *)page; 142 143 /* Check that struct page is either 56, 64, 72, 80, 88 or 96 bytes */ 144 BUILD_BUG_ON(sizeof(struct page) & 7); 145 BUILD_BUG_ON(sizeof(struct page) < 56); 146 BUILD_BUG_ON(sizeof(struct page) > 96); 147 148 switch (sizeof(struct page)) { 149 case 96: 150 _pp[11] = 0; 151 fallthrough; 152 case 88: 153 _pp[10] = 0; 154 fallthrough; 155 case 80: 156 _pp[9] = 0; 157 fallthrough; 158 case 72: 159 _pp[8] = 0; 160 fallthrough; 161 case 64: 162 _pp[7] = 0; 163 fallthrough; 164 case 56: 165 _pp[6] = 0; 166 _pp[5] = 0; 167 _pp[4] = 0; 168 _pp[3] = 0; 169 _pp[2] = 0; 170 _pp[1] = 0; 171 _pp[0] = 0; 172 } 173} 174#else 175#define mm_zero_struct_page(pp) ((void)memset((pp), 0, sizeof(struct page))) 176#endif 177 178/* 179 * Default maximum number of active map areas, this limits the number of vmas 180 * per mm struct. Users can overwrite this number by sysctl but there is a 181 * problem. 182 * 183 * When a program's coredump is generated as ELF format, a section is created 184 * per a vma. In ELF, the number of sections is represented in unsigned short. 185 * This means the number of sections should be smaller than 65535 at coredump. 186 * Because the kernel adds some informative sections to a image of program at 187 * generating coredump, we need some margin. The number of extra sections is 188 * 1-3 now and depends on arch. We use "5" as safe margin, here. 189 * 190 * ELF extended numbering allows more than 65535 sections, so 16-bit bound is 191 * not a hard limit any more. Although some userspace tools can be surprised by 192 * that. 193 */ 194#define MAPCOUNT_ELF_CORE_MARGIN (5) 195#define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN) 196 197extern int sysctl_max_map_count; 198 199extern unsigned long sysctl_user_reserve_kbytes; 200extern unsigned long sysctl_admin_reserve_kbytes; 201 202extern int sysctl_overcommit_memory; 203extern int sysctl_overcommit_ratio; 204extern unsigned long sysctl_overcommit_kbytes; 205 206int overcommit_ratio_handler(struct ctl_table *, int, void *, size_t *, 207 loff_t *); 208int overcommit_kbytes_handler(struct ctl_table *, int, void *, size_t *, 209 loff_t *); 210int overcommit_policy_handler(struct ctl_table *, int, void *, size_t *, 211 loff_t *); 212 213#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) 214#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n)) 215#define folio_page_idx(folio, p) (page_to_pfn(p) - folio_pfn(folio)) 216#else 217#define nth_page(page,n) ((page) + (n)) 218#define folio_page_idx(folio, p) ((p) - &(folio)->page) 219#endif 220 221/* to align the pointer to the (next) page boundary */ 222#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE) 223 224/* to align the pointer to the (prev) page boundary */ 225#define PAGE_ALIGN_DOWN(addr) ALIGN_DOWN(addr, PAGE_SIZE) 226 227/* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */ 228#define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)(addr), PAGE_SIZE) 229 230static inline struct folio *lru_to_folio(struct list_head *head) 231{ 232 return list_entry((head)->prev, struct folio, lru); 233} 234 235void setup_initial_init_mm(void *start_code, void *end_code, 236 void *end_data, void *brk); 237 238/* 239 * Linux kernel virtual memory manager primitives. 240 * The idea being to have a "virtual" mm in the same way 241 * we have a virtual fs - giving a cleaner interface to the 242 * mm details, and allowing different kinds of memory mappings 243 * (from shared memory to executable loading to arbitrary 244 * mmap() functions). 245 */ 246 247struct vm_area_struct *vm_area_alloc(struct mm_struct *); 248struct vm_area_struct *vm_area_dup(struct vm_area_struct *); 249void vm_area_free(struct vm_area_struct *); 250/* Use only if VMA has no other users */ 251void __vm_area_free(struct vm_area_struct *vma); 252 253#ifndef CONFIG_MMU 254extern struct rb_root nommu_region_tree; 255extern struct rw_semaphore nommu_region_sem; 256 257extern unsigned int kobjsize(const void *objp); 258#endif 259 260/* 261 * vm_flags in vm_area_struct, see mm_types.h. 262 * When changing, update also include/trace/events/mmflags.h 263 */ 264#define VM_NONE 0x00000000 265 266#define VM_READ 0x00000001 /* currently active flags */ 267#define VM_WRITE 0x00000002 268#define VM_EXEC 0x00000004 269#define VM_SHARED 0x00000008 270 271/* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */ 272#define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */ 273#define VM_MAYWRITE 0x00000020 274#define VM_MAYEXEC 0x00000040 275#define VM_MAYSHARE 0x00000080 276 277#define VM_GROWSDOWN 0x00000100 /* general info on the segment */ 278#ifdef CONFIG_MMU 279#define VM_UFFD_MISSING 0x00000200 /* missing pages tracking */ 280#else /* CONFIG_MMU */ 281#define VM_MAYOVERLAY 0x00000200 /* nommu: R/O MAP_PRIVATE mapping that might overlay a file mapping */ 282#define VM_UFFD_MISSING 0 283#endif /* CONFIG_MMU */ 284#define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */ 285#define VM_UFFD_WP 0x00001000 /* wrprotect pages tracking */ 286 287#define VM_LOCKED 0x00002000 288#define VM_IO 0x00004000 /* Memory mapped I/O or similar */ 289 290 /* Used by sys_madvise() */ 291#define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ 292#define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */ 293 294#define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ 295#define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ 296#define VM_LOCKONFAULT 0x00080000 /* Lock the pages covered when they are faulted in */ 297#define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ 298#define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */ 299#define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ 300#define VM_SYNC 0x00800000 /* Synchronous page faults */ 301#define VM_ARCH_1 0x01000000 /* Architecture-specific flag */ 302#define VM_WIPEONFORK 0x02000000 /* Wipe VMA contents in child. */ 303#define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */ 304 305#ifdef CONFIG_MEM_SOFT_DIRTY 306# define VM_SOFTDIRTY 0x08000000 /* Not soft dirty clean area */ 307#else 308# define VM_SOFTDIRTY 0 309#endif 310 311#define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */ 312#define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */ 313#define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */ 314#define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */ 315 316#ifdef CONFIG_ARCH_USES_HIGH_VMA_FLAGS 317#define VM_HIGH_ARCH_BIT_0 32 /* bit only usable on 64-bit architectures */ 318#define VM_HIGH_ARCH_BIT_1 33 /* bit only usable on 64-bit architectures */ 319#define VM_HIGH_ARCH_BIT_2 34 /* bit only usable on 64-bit architectures */ 320#define VM_HIGH_ARCH_BIT_3 35 /* bit only usable on 64-bit architectures */ 321#define VM_HIGH_ARCH_BIT_4 36 /* bit only usable on 64-bit architectures */ 322#define VM_HIGH_ARCH_BIT_5 37 /* bit only usable on 64-bit architectures */ 323#define VM_HIGH_ARCH_0 BIT(VM_HIGH_ARCH_BIT_0) 324#define VM_HIGH_ARCH_1 BIT(VM_HIGH_ARCH_BIT_1) 325#define VM_HIGH_ARCH_2 BIT(VM_HIGH_ARCH_BIT_2) 326#define VM_HIGH_ARCH_3 BIT(VM_HIGH_ARCH_BIT_3) 327#define VM_HIGH_ARCH_4 BIT(VM_HIGH_ARCH_BIT_4) 328#define VM_HIGH_ARCH_5 BIT(VM_HIGH_ARCH_BIT_5) 329#endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */ 330 331#ifdef CONFIG_ARCH_HAS_PKEYS 332# define VM_PKEY_SHIFT VM_HIGH_ARCH_BIT_0 333# define VM_PKEY_BIT0 VM_HIGH_ARCH_0 /* A protection key is a 4-bit value */ 334# define VM_PKEY_BIT1 VM_HIGH_ARCH_1 /* on x86 and 5-bit value on ppc64 */ 335# define VM_PKEY_BIT2 VM_HIGH_ARCH_2 336# define VM_PKEY_BIT3 VM_HIGH_ARCH_3 337#ifdef CONFIG_PPC 338# define VM_PKEY_BIT4 VM_HIGH_ARCH_4 339#else 340# define VM_PKEY_BIT4 0 341#endif 342#endif /* CONFIG_ARCH_HAS_PKEYS */ 343 344#ifdef CONFIG_X86_USER_SHADOW_STACK 345/* 346 * VM_SHADOW_STACK should not be set with VM_SHARED because of lack of 347 * support core mm. 348 * 349 * These VMAs will get a single end guard page. This helps userspace protect 350 * itself from attacks. A single page is enough for current shadow stack archs 351 * (x86). See the comments near alloc_shstk() in arch/x86/kernel/shstk.c 352 * for more details on the guard size. 353 */ 354# define VM_SHADOW_STACK VM_HIGH_ARCH_5 355#else 356# define VM_SHADOW_STACK VM_NONE 357#endif 358 359#if defined(CONFIG_X86) 360# define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */ 361#elif defined(CONFIG_PPC) 362# define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */ 363#elif defined(CONFIG_PARISC) 364# define VM_GROWSUP VM_ARCH_1 365#elif defined(CONFIG_SPARC64) 366# define VM_SPARC_ADI VM_ARCH_1 /* Uses ADI tag for access control */ 367# define VM_ARCH_CLEAR VM_SPARC_ADI 368#elif defined(CONFIG_ARM64) 369# define VM_ARM64_BTI VM_ARCH_1 /* BTI guarded page, a.k.a. GP bit */ 370# define VM_ARCH_CLEAR VM_ARM64_BTI 371#elif !defined(CONFIG_MMU) 372# define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */ 373#endif 374 375#if defined(CONFIG_ARM64_MTE) 376# define VM_MTE VM_HIGH_ARCH_0 /* Use Tagged memory for access control */ 377# define VM_MTE_ALLOWED VM_HIGH_ARCH_1 /* Tagged memory permitted */ 378#else 379# define VM_MTE VM_NONE 380# define VM_MTE_ALLOWED VM_NONE 381#endif 382 383#ifndef VM_GROWSUP 384# define VM_GROWSUP VM_NONE 385#endif 386 387#ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR 388# define VM_UFFD_MINOR_BIT 38 389# define VM_UFFD_MINOR BIT(VM_UFFD_MINOR_BIT) /* UFFD minor faults */ 390#else /* !CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ 391# define VM_UFFD_MINOR VM_NONE 392#endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ 393 394/* 395 * This flag is used to connect VFIO to arch specific KVM code. It 396 * indicates that the memory under this VMA is safe for use with any 397 * non-cachable memory type inside KVM. Some VFIO devices, on some 398 * platforms, are thought to be unsafe and can cause machine crashes 399 * if KVM does not lock down the memory type. 400 */ 401#ifdef CONFIG_64BIT 402#define VM_ALLOW_ANY_UNCACHED_BIT 39 403#define VM_ALLOW_ANY_UNCACHED BIT(VM_ALLOW_ANY_UNCACHED_BIT) 404#else 405#define VM_ALLOW_ANY_UNCACHED VM_NONE 406#endif 407 408/* Bits set in the VMA until the stack is in its final location */ 409#define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ | VM_STACK_EARLY) 410 411#define TASK_EXEC ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) 412 413/* Common data flag combinations */ 414#define VM_DATA_FLAGS_TSK_EXEC (VM_READ | VM_WRITE | TASK_EXEC | \ 415 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 416#define VM_DATA_FLAGS_NON_EXEC (VM_READ | VM_WRITE | VM_MAYREAD | \ 417 VM_MAYWRITE | VM_MAYEXEC) 418#define VM_DATA_FLAGS_EXEC (VM_READ | VM_WRITE | VM_EXEC | \ 419 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 420 421#ifndef VM_DATA_DEFAULT_FLAGS /* arch can override this */ 422#define VM_DATA_DEFAULT_FLAGS VM_DATA_FLAGS_EXEC 423#endif 424 425#ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */ 426#define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS 427#endif 428 429#define VM_STARTGAP_FLAGS (VM_GROWSDOWN | VM_SHADOW_STACK) 430 431#ifdef CONFIG_STACK_GROWSUP 432#define VM_STACK VM_GROWSUP 433#define VM_STACK_EARLY VM_GROWSDOWN 434#else 435#define VM_STACK VM_GROWSDOWN 436#define VM_STACK_EARLY 0 437#endif 438 439#define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 440 441/* VMA basic access permission flags */ 442#define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC) 443 444 445/* 446 * Special vmas that are non-mergable, non-mlock()able. 447 */ 448#define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP) 449 450/* This mask prevents VMA from being scanned with khugepaged */ 451#define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB) 452 453/* This mask defines which mm->def_flags a process can inherit its parent */ 454#define VM_INIT_DEF_MASK VM_NOHUGEPAGE 455 456/* This mask represents all the VMA flag bits used by mlock */ 457#define VM_LOCKED_MASK (VM_LOCKED | VM_LOCKONFAULT) 458 459/* Arch-specific flags to clear when updating VM flags on protection change */ 460#ifndef VM_ARCH_CLEAR 461# define VM_ARCH_CLEAR VM_NONE 462#endif 463#define VM_FLAGS_CLEAR (ARCH_VM_PKEY_FLAGS | VM_ARCH_CLEAR) 464 465/* 466 * mapping from the currently active vm_flags protection bits (the 467 * low four bits) to a page protection mask.. 468 */ 469 470/* 471 * The default fault flags that should be used by most of the 472 * arch-specific page fault handlers. 473 */ 474#define FAULT_FLAG_DEFAULT (FAULT_FLAG_ALLOW_RETRY | \ 475 FAULT_FLAG_KILLABLE | \ 476 FAULT_FLAG_INTERRUPTIBLE) 477 478/** 479 * fault_flag_allow_retry_first - check ALLOW_RETRY the first time 480 * @flags: Fault flags. 481 * 482 * This is mostly used for places where we want to try to avoid taking 483 * the mmap_lock for too long a time when waiting for another condition 484 * to change, in which case we can try to be polite to release the 485 * mmap_lock in the first round to avoid potential starvation of other 486 * processes that would also want the mmap_lock. 487 * 488 * Return: true if the page fault allows retry and this is the first 489 * attempt of the fault handling; false otherwise. 490 */ 491static inline bool fault_flag_allow_retry_first(enum fault_flag flags) 492{ 493 return (flags & FAULT_FLAG_ALLOW_RETRY) && 494 (!(flags & FAULT_FLAG_TRIED)); 495} 496 497#define FAULT_FLAG_TRACE \ 498 { FAULT_FLAG_WRITE, "WRITE" }, \ 499 { FAULT_FLAG_MKWRITE, "MKWRITE" }, \ 500 { FAULT_FLAG_ALLOW_RETRY, "ALLOW_RETRY" }, \ 501 { FAULT_FLAG_RETRY_NOWAIT, "RETRY_NOWAIT" }, \ 502 { FAULT_FLAG_KILLABLE, "KILLABLE" }, \ 503 { FAULT_FLAG_TRIED, "TRIED" }, \ 504 { FAULT_FLAG_USER, "USER" }, \ 505 { FAULT_FLAG_REMOTE, "REMOTE" }, \ 506 { FAULT_FLAG_INSTRUCTION, "INSTRUCTION" }, \ 507 { FAULT_FLAG_INTERRUPTIBLE, "INTERRUPTIBLE" }, \ 508 { FAULT_FLAG_VMA_LOCK, "VMA_LOCK" } 509 510/* 511 * vm_fault is filled by the pagefault handler and passed to the vma's 512 * ->fault function. The vma's ->fault is responsible for returning a bitmask 513 * of VM_FAULT_xxx flags that give details about how the fault was handled. 514 * 515 * MM layer fills up gfp_mask for page allocations but fault handler might 516 * alter it if its implementation requires a different allocation context. 517 * 518 * pgoff should be used in favour of virtual_address, if possible. 519 */ 520struct vm_fault { 521 const struct { 522 struct vm_area_struct *vma; /* Target VMA */ 523 gfp_t gfp_mask; /* gfp mask to be used for allocations */ 524 pgoff_t pgoff; /* Logical page offset based on vma */ 525 unsigned long address; /* Faulting virtual address - masked */ 526 unsigned long real_address; /* Faulting virtual address - unmasked */ 527 }; 528 enum fault_flag flags; /* FAULT_FLAG_xxx flags 529 * XXX: should really be 'const' */ 530 pmd_t *pmd; /* Pointer to pmd entry matching 531 * the 'address' */ 532 pud_t *pud; /* Pointer to pud entry matching 533 * the 'address' 534 */ 535 union { 536 pte_t orig_pte; /* Value of PTE at the time of fault */ 537 pmd_t orig_pmd; /* Value of PMD at the time of fault, 538 * used by PMD fault only. 539 */ 540 }; 541 542 struct page *cow_page; /* Page handler may use for COW fault */ 543 struct page *page; /* ->fault handlers should return a 544 * page here, unless VM_FAULT_NOPAGE 545 * is set (which is also implied by 546 * VM_FAULT_ERROR). 547 */ 548 /* These three entries are valid only while holding ptl lock */ 549 pte_t *pte; /* Pointer to pte entry matching 550 * the 'address'. NULL if the page 551 * table hasn't been allocated. 552 */ 553 spinlock_t *ptl; /* Page table lock. 554 * Protects pte page table if 'pte' 555 * is not NULL, otherwise pmd. 556 */ 557 pgtable_t prealloc_pte; /* Pre-allocated pte page table. 558 * vm_ops->map_pages() sets up a page 559 * table from atomic context. 560 * do_fault_around() pre-allocates 561 * page table to avoid allocation from 562 * atomic context. 563 */ 564}; 565 566/* 567 * These are the virtual MM functions - opening of an area, closing and 568 * unmapping it (needed to keep files on disk up-to-date etc), pointer 569 * to the functions called when a no-page or a wp-page exception occurs. 570 */ 571struct vm_operations_struct { 572 void (*open)(struct vm_area_struct * area); 573 /** 574 * @close: Called when the VMA is being removed from the MM. 575 * Context: User context. May sleep. Caller holds mmap_lock. 576 */ 577 void (*close)(struct vm_area_struct * area); 578 /* Called any time before splitting to check if it's allowed */ 579 int (*may_split)(struct vm_area_struct *area, unsigned long addr); 580 int (*mremap)(struct vm_area_struct *area); 581 /* 582 * Called by mprotect() to make driver-specific permission 583 * checks before mprotect() is finalised. The VMA must not 584 * be modified. Returns 0 if mprotect() can proceed. 585 */ 586 int (*mprotect)(struct vm_area_struct *vma, unsigned long start, 587 unsigned long end, unsigned long newflags); 588 vm_fault_t (*fault)(struct vm_fault *vmf); 589 vm_fault_t (*huge_fault)(struct vm_fault *vmf, unsigned int order); 590 vm_fault_t (*map_pages)(struct vm_fault *vmf, 591 pgoff_t start_pgoff, pgoff_t end_pgoff); 592 unsigned long (*pagesize)(struct vm_area_struct * area); 593 594 /* notification that a previously read-only page is about to become 595 * writable, if an error is returned it will cause a SIGBUS */ 596 vm_fault_t (*page_mkwrite)(struct vm_fault *vmf); 597 598 /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */ 599 vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf); 600 601 /* called by access_process_vm when get_user_pages() fails, typically 602 * for use by special VMAs. See also generic_access_phys() for a generic 603 * implementation useful for any iomem mapping. 604 */ 605 int (*access)(struct vm_area_struct *vma, unsigned long addr, 606 void *buf, int len, int write); 607 608 /* Called by the /proc/PID/maps code to ask the vma whether it 609 * has a special name. Returning non-NULL will also cause this 610 * vma to be dumped unconditionally. */ 611 const char *(*name)(struct vm_area_struct *vma); 612 613#ifdef CONFIG_NUMA 614 /* 615 * set_policy() op must add a reference to any non-NULL @new mempolicy 616 * to hold the policy upon return. Caller should pass NULL @new to 617 * remove a policy and fall back to surrounding context--i.e. do not 618 * install a MPOL_DEFAULT policy, nor the task or system default 619 * mempolicy. 620 */ 621 int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); 622 623 /* 624 * get_policy() op must add reference [mpol_get()] to any policy at 625 * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure 626 * in mm/mempolicy.c will do this automatically. 627 * get_policy() must NOT add a ref if the policy at (vma,addr) is not 628 * marked as MPOL_SHARED. vma policies are protected by the mmap_lock. 629 * If no [shared/vma] mempolicy exists at the addr, get_policy() op 630 * must return NULL--i.e., do not "fallback" to task or system default 631 * policy. 632 */ 633 struct mempolicy *(*get_policy)(struct vm_area_struct *vma, 634 unsigned long addr, pgoff_t *ilx); 635#endif 636 /* 637 * Called by vm_normal_page() for special PTEs to find the 638 * page for @addr. This is useful if the default behavior 639 * (using pte_page()) would not find the correct page. 640 */ 641 struct page *(*find_special_page)(struct vm_area_struct *vma, 642 unsigned long addr); 643}; 644 645#ifdef CONFIG_NUMA_BALANCING 646static inline void vma_numab_state_init(struct vm_area_struct *vma) 647{ 648 vma->numab_state = NULL; 649} 650static inline void vma_numab_state_free(struct vm_area_struct *vma) 651{ 652 kfree(vma->numab_state); 653} 654#else 655static inline void vma_numab_state_init(struct vm_area_struct *vma) {} 656static inline void vma_numab_state_free(struct vm_area_struct *vma) {} 657#endif /* CONFIG_NUMA_BALANCING */ 658 659#ifdef CONFIG_PER_VMA_LOCK 660/* 661 * Try to read-lock a vma. The function is allowed to occasionally yield false 662 * locked result to avoid performance overhead, in which case we fall back to 663 * using mmap_lock. The function should never yield false unlocked result. 664 */ 665static inline bool vma_start_read(struct vm_area_struct *vma) 666{ 667 /* 668 * Check before locking. A race might cause false locked result. 669 * We can use READ_ONCE() for the mm_lock_seq here, and don't need 670 * ACQUIRE semantics, because this is just a lockless check whose result 671 * we don't rely on for anything - the mm_lock_seq read against which we 672 * need ordering is below. 673 */ 674 if (READ_ONCE(vma->vm_lock_seq) == READ_ONCE(vma->vm_mm->mm_lock_seq)) 675 return false; 676 677 if (unlikely(down_read_trylock(&vma->vm_lock->lock) == 0)) 678 return false; 679 680 /* 681 * Overflow might produce false locked result. 682 * False unlocked result is impossible because we modify and check 683 * vma->vm_lock_seq under vma->vm_lock protection and mm->mm_lock_seq 684 * modification invalidates all existing locks. 685 * 686 * We must use ACQUIRE semantics for the mm_lock_seq so that if we are 687 * racing with vma_end_write_all(), we only start reading from the VMA 688 * after it has been unlocked. 689 * This pairs with RELEASE semantics in vma_end_write_all(). 690 */ 691 if (unlikely(vma->vm_lock_seq == smp_load_acquire(&vma->vm_mm->mm_lock_seq))) { 692 up_read(&vma->vm_lock->lock); 693 return false; 694 } 695 return true; 696} 697 698static inline void vma_end_read(struct vm_area_struct *vma) 699{ 700 rcu_read_lock(); /* keeps vma alive till the end of up_read */ 701 up_read(&vma->vm_lock->lock); 702 rcu_read_unlock(); 703} 704 705/* WARNING! Can only be used if mmap_lock is expected to be write-locked */ 706static bool __is_vma_write_locked(struct vm_area_struct *vma, int *mm_lock_seq) 707{ 708 mmap_assert_write_locked(vma->vm_mm); 709 710 /* 711 * current task is holding mmap_write_lock, both vma->vm_lock_seq and 712 * mm->mm_lock_seq can't be concurrently modified. 713 */ 714 *mm_lock_seq = vma->vm_mm->mm_lock_seq; 715 return (vma->vm_lock_seq == *mm_lock_seq); 716} 717 718/* 719 * Begin writing to a VMA. 720 * Exclude concurrent readers under the per-VMA lock until the currently 721 * write-locked mmap_lock is dropped or downgraded. 722 */ 723static inline void vma_start_write(struct vm_area_struct *vma) 724{ 725 int mm_lock_seq; 726 727 if (__is_vma_write_locked(vma, &mm_lock_seq)) 728 return; 729 730 down_write(&vma->vm_lock->lock); 731 /* 732 * We should use WRITE_ONCE() here because we can have concurrent reads 733 * from the early lockless pessimistic check in vma_start_read(). 734 * We don't really care about the correctness of that early check, but 735 * we should use WRITE_ONCE() for cleanliness and to keep KCSAN happy. 736 */ 737 WRITE_ONCE(vma->vm_lock_seq, mm_lock_seq); 738 up_write(&vma->vm_lock->lock); 739} 740 741static inline void vma_assert_write_locked(struct vm_area_struct *vma) 742{ 743 int mm_lock_seq; 744 745 VM_BUG_ON_VMA(!__is_vma_write_locked(vma, &mm_lock_seq), vma); 746} 747 748static inline void vma_assert_locked(struct vm_area_struct *vma) 749{ 750 if (!rwsem_is_locked(&vma->vm_lock->lock)) 751 vma_assert_write_locked(vma); 752} 753 754static inline void vma_mark_detached(struct vm_area_struct *vma, bool detached) 755{ 756 /* When detaching vma should be write-locked */ 757 if (detached) 758 vma_assert_write_locked(vma); 759 vma->detached = detached; 760} 761 762static inline void release_fault_lock(struct vm_fault *vmf) 763{ 764 if (vmf->flags & FAULT_FLAG_VMA_LOCK) 765 vma_end_read(vmf->vma); 766 else 767 mmap_read_unlock(vmf->vma->vm_mm); 768} 769 770static inline void assert_fault_locked(struct vm_fault *vmf) 771{ 772 if (vmf->flags & FAULT_FLAG_VMA_LOCK) 773 vma_assert_locked(vmf->vma); 774 else 775 mmap_assert_locked(vmf->vma->vm_mm); 776} 777 778struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, 779 unsigned long address); 780 781#else /* CONFIG_PER_VMA_LOCK */ 782 783static inline bool vma_start_read(struct vm_area_struct *vma) 784 { return false; } 785static inline void vma_end_read(struct vm_area_struct *vma) {} 786static inline void vma_start_write(struct vm_area_struct *vma) {} 787static inline void vma_assert_write_locked(struct vm_area_struct *vma) 788 { mmap_assert_write_locked(vma->vm_mm); } 789static inline void vma_mark_detached(struct vm_area_struct *vma, 790 bool detached) {} 791 792static inline struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, 793 unsigned long address) 794{ 795 return NULL; 796} 797 798static inline void vma_assert_locked(struct vm_area_struct *vma) 799{ 800 mmap_assert_locked(vma->vm_mm); 801} 802 803static inline void release_fault_lock(struct vm_fault *vmf) 804{ 805 mmap_read_unlock(vmf->vma->vm_mm); 806} 807 808static inline void assert_fault_locked(struct vm_fault *vmf) 809{ 810 mmap_assert_locked(vmf->vma->vm_mm); 811} 812 813#endif /* CONFIG_PER_VMA_LOCK */ 814 815extern const struct vm_operations_struct vma_dummy_vm_ops; 816 817/* 818 * WARNING: vma_init does not initialize vma->vm_lock. 819 * Use vm_area_alloc()/vm_area_free() if vma needs locking. 820 */ 821static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) 822{ 823 memset(vma, 0, sizeof(*vma)); 824 vma->vm_mm = mm; 825 vma->vm_ops = &vma_dummy_vm_ops; 826 INIT_LIST_HEAD(&vma->anon_vma_chain); 827 vma_mark_detached(vma, false); 828 vma_numab_state_init(vma); 829} 830 831/* Use when VMA is not part of the VMA tree and needs no locking */ 832static inline void vm_flags_init(struct vm_area_struct *vma, 833 vm_flags_t flags) 834{ 835 ACCESS_PRIVATE(vma, __vm_flags) = flags; 836} 837 838/* 839 * Use when VMA is part of the VMA tree and modifications need coordination 840 * Note: vm_flags_reset and vm_flags_reset_once do not lock the vma and 841 * it should be locked explicitly beforehand. 842 */ 843static inline void vm_flags_reset(struct vm_area_struct *vma, 844 vm_flags_t flags) 845{ 846 vma_assert_write_locked(vma); 847 vm_flags_init(vma, flags); 848} 849 850static inline void vm_flags_reset_once(struct vm_area_struct *vma, 851 vm_flags_t flags) 852{ 853 vma_assert_write_locked(vma); 854 WRITE_ONCE(ACCESS_PRIVATE(vma, __vm_flags), flags); 855} 856 857static inline void vm_flags_set(struct vm_area_struct *vma, 858 vm_flags_t flags) 859{ 860 vma_start_write(vma); 861 ACCESS_PRIVATE(vma, __vm_flags) |= flags; 862} 863 864static inline void vm_flags_clear(struct vm_area_struct *vma, 865 vm_flags_t flags) 866{ 867 vma_start_write(vma); 868 ACCESS_PRIVATE(vma, __vm_flags) &= ~flags; 869} 870 871/* 872 * Use only if VMA is not part of the VMA tree or has no other users and 873 * therefore needs no locking. 874 */ 875static inline void __vm_flags_mod(struct vm_area_struct *vma, 876 vm_flags_t set, vm_flags_t clear) 877{ 878 vm_flags_init(vma, (vma->vm_flags | set) & ~clear); 879} 880 881/* 882 * Use only when the order of set/clear operations is unimportant, otherwise 883 * use vm_flags_{set|clear} explicitly. 884 */ 885static inline void vm_flags_mod(struct vm_area_struct *vma, 886 vm_flags_t set, vm_flags_t clear) 887{ 888 vma_start_write(vma); 889 __vm_flags_mod(vma, set, clear); 890} 891 892static inline void vma_set_anonymous(struct vm_area_struct *vma) 893{ 894 vma->vm_ops = NULL; 895} 896 897static inline bool vma_is_anonymous(struct vm_area_struct *vma) 898{ 899 return !vma->vm_ops; 900} 901 902/* 903 * Indicate if the VMA is a heap for the given task; for 904 * /proc/PID/maps that is the heap of the main task. 905 */ 906static inline bool vma_is_initial_heap(const struct vm_area_struct *vma) 907{ 908 return vma->vm_start < vma->vm_mm->brk && 909 vma->vm_end > vma->vm_mm->start_brk; 910} 911 912/* 913 * Indicate if the VMA is a stack for the given task; for 914 * /proc/PID/maps that is the stack of the main task. 915 */ 916static inline bool vma_is_initial_stack(const struct vm_area_struct *vma) 917{ 918 /* 919 * We make no effort to guess what a given thread considers to be 920 * its "stack". It's not even well-defined for programs written 921 * languages like Go. 922 */ 923 return vma->vm_start <= vma->vm_mm->start_stack && 924 vma->vm_end >= vma->vm_mm->start_stack; 925} 926 927static inline bool vma_is_temporary_stack(struct vm_area_struct *vma) 928{ 929 int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP); 930 931 if (!maybe_stack) 932 return false; 933 934 if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) == 935 VM_STACK_INCOMPLETE_SETUP) 936 return true; 937 938 return false; 939} 940 941static inline bool vma_is_foreign(struct vm_area_struct *vma) 942{ 943 if (!current->mm) 944 return true; 945 946 if (current->mm != vma->vm_mm) 947 return true; 948 949 return false; 950} 951 952static inline bool vma_is_accessible(struct vm_area_struct *vma) 953{ 954 return vma->vm_flags & VM_ACCESS_FLAGS; 955} 956 957static inline bool is_shared_maywrite(vm_flags_t vm_flags) 958{ 959 return (vm_flags & (VM_SHARED | VM_MAYWRITE)) == 960 (VM_SHARED | VM_MAYWRITE); 961} 962 963static inline bool vma_is_shared_maywrite(struct vm_area_struct *vma) 964{ 965 return is_shared_maywrite(vma->vm_flags); 966} 967 968static inline 969struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max) 970{ 971 return mas_find(&vmi->mas, max - 1); 972} 973 974static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi) 975{ 976 /* 977 * Uses mas_find() to get the first VMA when the iterator starts. 978 * Calling mas_next() could skip the first entry. 979 */ 980 return mas_find(&vmi->mas, ULONG_MAX); 981} 982 983static inline 984struct vm_area_struct *vma_iter_next_range(struct vma_iterator *vmi) 985{ 986 return mas_next_range(&vmi->mas, ULONG_MAX); 987} 988 989 990static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi) 991{ 992 return mas_prev(&vmi->mas, 0); 993} 994 995static inline 996struct vm_area_struct *vma_iter_prev_range(struct vma_iterator *vmi) 997{ 998 return mas_prev_range(&vmi->mas, 0); 999} 1000 1001static inline unsigned long vma_iter_addr(struct vma_iterator *vmi) 1002{ 1003 return vmi->mas.index; 1004} 1005 1006static inline unsigned long vma_iter_end(struct vma_iterator *vmi) 1007{ 1008 return vmi->mas.last + 1; 1009} 1010static inline int vma_iter_bulk_alloc(struct vma_iterator *vmi, 1011 unsigned long count) 1012{ 1013 return mas_expected_entries(&vmi->mas, count); 1014} 1015 1016static inline int vma_iter_clear_gfp(struct vma_iterator *vmi, 1017 unsigned long start, unsigned long end, gfp_t gfp) 1018{ 1019 __mas_set_range(&vmi->mas, start, end - 1); 1020 mas_store_gfp(&vmi->mas, NULL, gfp); 1021 if (unlikely(mas_is_err(&vmi->mas))) 1022 return -ENOMEM; 1023 1024 return 0; 1025} 1026 1027/* Free any unused preallocations */ 1028static inline void vma_iter_free(struct vma_iterator *vmi) 1029{ 1030 mas_destroy(&vmi->mas); 1031} 1032 1033static inline int vma_iter_bulk_store(struct vma_iterator *vmi, 1034 struct vm_area_struct *vma) 1035{ 1036 vmi->mas.index = vma->vm_start; 1037 vmi->mas.last = vma->vm_end - 1; 1038 mas_store(&vmi->mas, vma); 1039 if (unlikely(mas_is_err(&vmi->mas))) 1040 return -ENOMEM; 1041 1042 return 0; 1043} 1044 1045static inline void vma_iter_invalidate(struct vma_iterator *vmi) 1046{ 1047 mas_pause(&vmi->mas); 1048} 1049 1050static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr) 1051{ 1052 mas_set(&vmi->mas, addr); 1053} 1054 1055#define for_each_vma(__vmi, __vma) \ 1056 while (((__vma) = vma_next(&(__vmi))) != NULL) 1057 1058/* The MM code likes to work with exclusive end addresses */ 1059#define for_each_vma_range(__vmi, __vma, __end) \ 1060 while (((__vma) = vma_find(&(__vmi), (__end))) != NULL) 1061 1062#ifdef CONFIG_SHMEM 1063/* 1064 * The vma_is_shmem is not inline because it is used only by slow 1065 * paths in userfault. 1066 */ 1067bool vma_is_shmem(struct vm_area_struct *vma); 1068bool vma_is_anon_shmem(struct vm_area_struct *vma); 1069#else 1070static inline bool vma_is_shmem(struct vm_area_struct *vma) { return false; } 1071static inline bool vma_is_anon_shmem(struct vm_area_struct *vma) { return false; } 1072#endif 1073 1074int vma_is_stack_for_current(struct vm_area_struct *vma); 1075 1076/* flush_tlb_range() takes a vma, not a mm, and can care about flags */ 1077#define TLB_FLUSH_VMA(mm,flags) { .vm_mm = (mm), .vm_flags = (flags) } 1078 1079struct mmu_gather; 1080struct inode; 1081 1082/* 1083 * compound_order() can be called without holding a reference, which means 1084 * that niceties like page_folio() don't work. These callers should be 1085 * prepared to handle wild return values. For example, PG_head may be 1086 * set before the order is initialised, or this may be a tail page. 1087 * See compaction.c for some good examples. 1088 */ 1089static inline unsigned int compound_order(struct page *page) 1090{ 1091 struct folio *folio = (struct folio *)page; 1092 1093 if (!test_bit(PG_head, &folio->flags)) 1094 return 0; 1095 return folio->_flags_1 & 0xff; 1096} 1097 1098/** 1099 * folio_order - The allocation order of a folio. 1100 * @folio: The folio. 1101 * 1102 * A folio is composed of 2^order pages. See get_order() for the definition 1103 * of order. 1104 * 1105 * Return: The order of the folio. 1106 */ 1107static inline unsigned int folio_order(struct folio *folio) 1108{ 1109 if (!folio_test_large(folio)) 1110 return 0; 1111 return folio->_flags_1 & 0xff; 1112} 1113 1114#include <linux/huge_mm.h> 1115 1116/* 1117 * Methods to modify the page usage count. 1118 * 1119 * What counts for a page usage: 1120 * - cache mapping (page->mapping) 1121 * - private data (page->private) 1122 * - page mapped in a task's page tables, each mapping 1123 * is counted separately 1124 * 1125 * Also, many kernel routines increase the page count before a critical 1126 * routine so they can be sure the page doesn't go away from under them. 1127 */ 1128 1129/* 1130 * Drop a ref, return true if the refcount fell to zero (the page has no users) 1131 */ 1132static inline int put_page_testzero(struct page *page) 1133{ 1134 VM_BUG_ON_PAGE(page_ref_count(page) == 0, page); 1135 return page_ref_dec_and_test(page); 1136} 1137 1138static inline int folio_put_testzero(struct folio *folio) 1139{ 1140 return put_page_testzero(&folio->page); 1141} 1142 1143/* 1144 * Try to grab a ref unless the page has a refcount of zero, return false if 1145 * that is the case. 1146 * This can be called when MMU is off so it must not access 1147 * any of the virtual mappings. 1148 */ 1149static inline bool get_page_unless_zero(struct page *page) 1150{ 1151 return page_ref_add_unless(page, 1, 0); 1152} 1153 1154static inline struct folio *folio_get_nontail_page(struct page *page) 1155{ 1156 if (unlikely(!get_page_unless_zero(page))) 1157 return NULL; 1158 return (struct folio *)page; 1159} 1160 1161extern int page_is_ram(unsigned long pfn); 1162 1163enum { 1164 REGION_INTERSECTS, 1165 REGION_DISJOINT, 1166 REGION_MIXED, 1167}; 1168 1169int region_intersects(resource_size_t offset, size_t size, unsigned long flags, 1170 unsigned long desc); 1171 1172/* Support for virtually mapped pages */ 1173struct page *vmalloc_to_page(const void *addr); 1174unsigned long vmalloc_to_pfn(const void *addr); 1175 1176/* 1177 * Determine if an address is within the vmalloc range 1178 * 1179 * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there 1180 * is no special casing required. 1181 */ 1182#ifdef CONFIG_MMU 1183extern bool is_vmalloc_addr(const void *x); 1184extern int is_vmalloc_or_module_addr(const void *x); 1185#else 1186static inline bool is_vmalloc_addr(const void *x) 1187{ 1188 return false; 1189} 1190static inline int is_vmalloc_or_module_addr(const void *x) 1191{ 1192 return 0; 1193} 1194#endif 1195 1196/* 1197 * How many times the entire folio is mapped as a single unit (eg by a 1198 * PMD or PUD entry). This is probably not what you want, except for 1199 * debugging purposes - it does not include PTE-mapped sub-pages; look 1200 * at folio_mapcount() or page_mapcount() instead. 1201 */ 1202static inline int folio_entire_mapcount(struct folio *folio) 1203{ 1204 VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); 1205 return atomic_read(&folio->_entire_mapcount) + 1; 1206} 1207 1208/* 1209 * The atomic page->_mapcount, starts from -1: so that transitions 1210 * both from it and to it can be tracked, using atomic_inc_and_test 1211 * and atomic_add_negative(-1). 1212 */ 1213static inline void page_mapcount_reset(struct page *page) 1214{ 1215 atomic_set(&(page)->_mapcount, -1); 1216} 1217 1218/** 1219 * page_mapcount() - Number of times this precise page is mapped. 1220 * @page: The page. 1221 * 1222 * The number of times this page is mapped. If this page is part of 1223 * a large folio, it includes the number of times this page is mapped 1224 * as part of that folio. 1225 * 1226 * The result is undefined for pages which cannot be mapped into userspace. 1227 * For example SLAB or special types of pages. See function page_has_type(). 1228 * They use this field in struct page differently. 1229 */ 1230static inline int page_mapcount(struct page *page) 1231{ 1232 int mapcount = atomic_read(&page->_mapcount) + 1; 1233 1234 if (unlikely(PageCompound(page))) 1235 mapcount += folio_entire_mapcount(page_folio(page)); 1236 1237 return mapcount; 1238} 1239 1240int folio_total_mapcount(struct folio *folio); 1241 1242/** 1243 * folio_mapcount() - Calculate the number of mappings of this folio. 1244 * @folio: The folio. 1245 * 1246 * A large folio tracks both how many times the entire folio is mapped, 1247 * and how many times each individual page in the folio is mapped. 1248 * This function calculates the total number of times the folio is 1249 * mapped. 1250 * 1251 * Return: The number of times this folio is mapped. 1252 */ 1253static inline int folio_mapcount(struct folio *folio) 1254{ 1255 if (likely(!folio_test_large(folio))) 1256 return atomic_read(&folio->_mapcount) + 1; 1257 return folio_total_mapcount(folio); 1258} 1259 1260static inline bool folio_large_is_mapped(struct folio *folio) 1261{ 1262 /* 1263 * Reading _entire_mapcount below could be omitted if hugetlb 1264 * participated in incrementing nr_pages_mapped when compound mapped. 1265 */ 1266 return atomic_read(&folio->_nr_pages_mapped) > 0 || 1267 atomic_read(&folio->_entire_mapcount) >= 0; 1268} 1269 1270/** 1271 * folio_mapped - Is this folio mapped into userspace? 1272 * @folio: The folio. 1273 * 1274 * Return: True if any page in this folio is referenced by user page tables. 1275 */ 1276static inline bool folio_mapped(struct folio *folio) 1277{ 1278 if (likely(!folio_test_large(folio))) 1279 return atomic_read(&folio->_mapcount) >= 0; 1280 return folio_large_is_mapped(folio); 1281} 1282 1283/* 1284 * Return true if this page is mapped into pagetables. 1285 * For compound page it returns true if any sub-page of compound page is mapped, 1286 * even if this particular sub-page is not itself mapped by any PTE or PMD. 1287 */ 1288static inline bool page_mapped(struct page *page) 1289{ 1290 if (likely(!PageCompound(page))) 1291 return atomic_read(&page->_mapcount) >= 0; 1292 return folio_large_is_mapped(page_folio(page)); 1293} 1294 1295static inline struct page *virt_to_head_page(const void *x) 1296{ 1297 struct page *page = virt_to_page(x); 1298 1299 return compound_head(page); 1300} 1301 1302static inline struct folio *virt_to_folio(const void *x) 1303{ 1304 struct page *page = virt_to_page(x); 1305 1306 return page_folio(page); 1307} 1308 1309void __folio_put(struct folio *folio); 1310 1311void put_pages_list(struct list_head *pages); 1312 1313void split_page(struct page *page, unsigned int order); 1314void folio_copy(struct folio *dst, struct folio *src); 1315 1316unsigned long nr_free_buffer_pages(void); 1317 1318void destroy_large_folio(struct folio *folio); 1319 1320/* Returns the number of bytes in this potentially compound page. */ 1321static inline unsigned long page_size(struct page *page) 1322{ 1323 return PAGE_SIZE << compound_order(page); 1324} 1325 1326/* Returns the number of bits needed for the number of bytes in a page */ 1327static inline unsigned int page_shift(struct page *page) 1328{ 1329 return PAGE_SHIFT + compound_order(page); 1330} 1331 1332/** 1333 * thp_order - Order of a transparent huge page. 1334 * @page: Head page of a transparent huge page. 1335 */ 1336static inline unsigned int thp_order(struct page *page) 1337{ 1338 VM_BUG_ON_PGFLAGS(PageTail(page), page); 1339 return compound_order(page); 1340} 1341 1342/** 1343 * thp_size - Size of a transparent huge page. 1344 * @page: Head page of a transparent huge page. 1345 * 1346 * Return: Number of bytes in this page. 1347 */ 1348static inline unsigned long thp_size(struct page *page) 1349{ 1350 return PAGE_SIZE << thp_order(page); 1351} 1352 1353#ifdef CONFIG_MMU 1354/* 1355 * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when 1356 * servicing faults for write access. In the normal case, do always want 1357 * pte_mkwrite. But get_user_pages can cause write faults for mappings 1358 * that do not have writing enabled, when used by access_process_vm. 1359 */ 1360static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma) 1361{ 1362 if (likely(vma->vm_flags & VM_WRITE)) 1363 pte = pte_mkwrite(pte, vma); 1364 return pte; 1365} 1366 1367vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page); 1368void set_pte_range(struct vm_fault *vmf, struct folio *folio, 1369 struct page *page, unsigned int nr, unsigned long addr); 1370 1371vm_fault_t finish_fault(struct vm_fault *vmf); 1372#endif 1373 1374/* 1375 * Multiple processes may "see" the same page. E.g. for untouched 1376 * mappings of /dev/null, all processes see the same page full of 1377 * zeroes, and text pages of executables and shared libraries have 1378 * only one copy in memory, at most, normally. 1379 * 1380 * For the non-reserved pages, page_count(page) denotes a reference count. 1381 * page_count() == 0 means the page is free. page->lru is then used for 1382 * freelist management in the buddy allocator. 1383 * page_count() > 0 means the page has been allocated. 1384 * 1385 * Pages are allocated by the slab allocator in order to provide memory 1386 * to kmalloc and kmem_cache_alloc. In this case, the management of the 1387 * page, and the fields in 'struct page' are the responsibility of mm/slab.c 1388 * unless a particular usage is carefully commented. (the responsibility of 1389 * freeing the kmalloc memory is the caller's, of course). 1390 * 1391 * A page may be used by anyone else who does a __get_free_page(). 1392 * In this case, page_count still tracks the references, and should only 1393 * be used through the normal accessor functions. The top bits of page->flags 1394 * and page->virtual store page management information, but all other fields 1395 * are unused and could be used privately, carefully. The management of this 1396 * page is the responsibility of the one who allocated it, and those who have 1397 * subsequently been given references to it. 1398 * 1399 * The other pages (we may call them "pagecache pages") are completely 1400 * managed by the Linux memory manager: I/O, buffers, swapping etc. 1401 * The following discussion applies only to them. 1402 * 1403 * A pagecache page contains an opaque `private' member, which belongs to the 1404 * page's address_space. Usually, this is the address of a circular list of 1405 * the page's disk buffers. PG_private must be set to tell the VM to call 1406 * into the filesystem to release these pages. 1407 * 1408 * A page may belong to an inode's memory mapping. In this case, page->mapping 1409 * is the pointer to the inode, and page->index is the file offset of the page, 1410 * in units of PAGE_SIZE. 1411 * 1412 * If pagecache pages are not associated with an inode, they are said to be 1413 * anonymous pages. These may become associated with the swapcache, and in that 1414 * case PG_swapcache is set, and page->private is an offset into the swapcache. 1415 * 1416 * In either case (swapcache or inode backed), the pagecache itself holds one 1417 * reference to the page. Setting PG_private should also increment the 1418 * refcount. The each user mapping also has a reference to the page. 1419 * 1420 * The pagecache pages are stored in a per-mapping radix tree, which is 1421 * rooted at mapping->i_pages, and indexed by offset. 1422 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space 1423 * lists, we instead now tag pages as dirty/writeback in the radix tree. 1424 * 1425 * All pagecache pages may be subject to I/O: 1426 * - inode pages may need to be read from disk, 1427 * - inode pages which have been modified and are MAP_SHARED may need 1428 * to be written back to the inode on disk, 1429 * - anonymous pages (including MAP_PRIVATE file mappings) which have been 1430 * modified may need to be swapped out to swap space and (later) to be read 1431 * back into memory. 1432 */ 1433 1434#if defined(CONFIG_ZONE_DEVICE) && defined(CONFIG_FS_DAX) 1435DECLARE_STATIC_KEY_FALSE(devmap_managed_key); 1436 1437bool __put_devmap_managed_page_refs(struct page *page, int refs); 1438static inline bool put_devmap_managed_page_refs(struct page *page, int refs) 1439{ 1440 if (!static_branch_unlikely(&devmap_managed_key)) 1441 return false; 1442 if (!is_zone_device_page(page)) 1443 return false; 1444 return __put_devmap_managed_page_refs(page, refs); 1445} 1446#else /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */ 1447static inline bool put_devmap_managed_page_refs(struct page *page, int refs) 1448{ 1449 return false; 1450} 1451#endif /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */ 1452 1453static inline bool put_devmap_managed_page(struct page *page) 1454{ 1455 return put_devmap_managed_page_refs(page, 1); 1456} 1457 1458/* 127: arbitrary random number, small enough to assemble well */ 1459#define folio_ref_zero_or_close_to_overflow(folio) \ 1460 ((unsigned int) folio_ref_count(folio) + 127u <= 127u) 1461 1462/** 1463 * folio_get - Increment the reference count on a folio. 1464 * @folio: The folio. 1465 * 1466 * Context: May be called in any context, as long as you know that 1467 * you have a refcount on the folio. If you do not already have one, 1468 * folio_try_get() may be the right interface for you to use. 1469 */ 1470static inline void folio_get(struct folio *folio) 1471{ 1472 VM_BUG_ON_FOLIO(folio_ref_zero_or_close_to_overflow(folio), folio); 1473 folio_ref_inc(folio); 1474} 1475 1476static inline void get_page(struct page *page) 1477{ 1478 folio_get(page_folio(page)); 1479} 1480 1481static inline __must_check bool try_get_page(struct page *page) 1482{ 1483 page = compound_head(page); 1484 if (WARN_ON_ONCE(page_ref_count(page) <= 0)) 1485 return false; 1486 page_ref_inc(page); 1487 return true; 1488} 1489 1490/** 1491 * folio_put - Decrement the reference count on a folio. 1492 * @folio: The folio. 1493 * 1494 * If the folio's reference count reaches zero, the memory will be 1495 * released back to the page allocator and may be used by another 1496 * allocation immediately. Do not access the memory or the struct folio 1497 * after calling folio_put() unless you can be sure that it wasn't the 1498 * last reference. 1499 * 1500 * Context: May be called in process or interrupt context, but not in NMI 1501 * context. May be called while holding a spinlock. 1502 */ 1503static inline void folio_put(struct folio *folio) 1504{ 1505 if (folio_put_testzero(folio)) 1506 __folio_put(folio); 1507} 1508 1509/** 1510 * folio_put_refs - Reduce the reference count on a folio. 1511 * @folio: The folio. 1512 * @refs: The amount to subtract from the folio's reference count. 1513 * 1514 * If the folio's reference count reaches zero, the memory will be 1515 * released back to the page allocator and may be used by another 1516 * allocation immediately. Do not access the memory or the struct folio 1517 * after calling folio_put_refs() unless you can be sure that these weren't 1518 * the last references. 1519 * 1520 * Context: May be called in process or interrupt context, but not in NMI 1521 * context. May be called while holding a spinlock. 1522 */ 1523static inline void folio_put_refs(struct folio *folio, int refs) 1524{ 1525 if (folio_ref_sub_and_test(folio, refs)) 1526 __folio_put(folio); 1527} 1528 1529void folios_put_refs(struct folio_batch *folios, unsigned int *refs); 1530 1531/* 1532 * union release_pages_arg - an array of pages or folios 1533 * 1534 * release_pages() releases a simple array of multiple pages, and 1535 * accepts various different forms of said page array: either 1536 * a regular old boring array of pages, an array of folios, or 1537 * an array of encoded page pointers. 1538 * 1539 * The transparent union syntax for this kind of "any of these 1540 * argument types" is all kinds of ugly, so look away. 1541 */ 1542typedef union { 1543 struct page **pages; 1544 struct folio **folios; 1545 struct encoded_page **encoded_pages; 1546} release_pages_arg __attribute__ ((__transparent_union__)); 1547 1548void release_pages(release_pages_arg, int nr); 1549 1550/** 1551 * folios_put - Decrement the reference count on an array of folios. 1552 * @folios: The folios. 1553 * 1554 * Like folio_put(), but for a batch of folios. This is more efficient 1555 * than writing the loop yourself as it will optimise the locks which need 1556 * to be taken if the folios are freed. The folios batch is returned 1557 * empty and ready to be reused for another batch; there is no need to 1558 * reinitialise it. 1559 * 1560 * Context: May be called in process or interrupt context, but not in NMI 1561 * context. May be called while holding a spinlock. 1562 */ 1563static inline void folios_put(struct folio_batch *folios) 1564{ 1565 folios_put_refs(folios, NULL); 1566} 1567 1568static inline void put_page(struct page *page) 1569{ 1570 struct folio *folio = page_folio(page); 1571 1572 /* 1573 * For some devmap managed pages we need to catch refcount transition 1574 * from 2 to 1: 1575 */ 1576 if (put_devmap_managed_page(&folio->page)) 1577 return; 1578 folio_put(folio); 1579} 1580 1581/* 1582 * GUP_PIN_COUNTING_BIAS, and the associated functions that use it, overload 1583 * the page's refcount so that two separate items are tracked: the original page 1584 * reference count, and also a new count of how many pin_user_pages() calls were 1585 * made against the page. ("gup-pinned" is another term for the latter). 1586 * 1587 * With this scheme, pin_user_pages() becomes special: such pages are marked as 1588 * distinct from normal pages. As such, the unpin_user_page() call (and its 1589 * variants) must be used in order to release gup-pinned pages. 1590 * 1591 * Choice of value: 1592 * 1593 * By making GUP_PIN_COUNTING_BIAS a power of two, debugging of page reference 1594 * counts with respect to pin_user_pages() and unpin_user_page() becomes 1595 * simpler, due to the fact that adding an even power of two to the page 1596 * refcount has the effect of using only the upper N bits, for the code that 1597 * counts up using the bias value. This means that the lower bits are left for 1598 * the exclusive use of the original code that increments and decrements by one 1599 * (or at least, by much smaller values than the bias value). 1600 * 1601 * Of course, once the lower bits overflow into the upper bits (and this is 1602 * OK, because subtraction recovers the original values), then visual inspection 1603 * no longer suffices to directly view the separate counts. However, for normal 1604 * applications that don't have huge page reference counts, this won't be an 1605 * issue. 1606 * 1607 * Locking: the lockless algorithm described in folio_try_get_rcu() 1608 * provides safe operation for get_user_pages(), page_mkclean() and 1609 * other calls that race to set up page table entries. 1610 */ 1611#define GUP_PIN_COUNTING_BIAS (1U << 10) 1612 1613void unpin_user_page(struct page *page); 1614void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages, 1615 bool make_dirty); 1616void unpin_user_page_range_dirty_lock(struct page *page, unsigned long npages, 1617 bool make_dirty); 1618void unpin_user_pages(struct page **pages, unsigned long npages); 1619 1620static inline bool is_cow_mapping(vm_flags_t flags) 1621{ 1622 return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE; 1623} 1624 1625#ifndef CONFIG_MMU 1626static inline bool is_nommu_shared_mapping(vm_flags_t flags) 1627{ 1628 /* 1629 * NOMMU shared mappings are ordinary MAP_SHARED mappings and selected 1630 * R/O MAP_PRIVATE file mappings that are an effective R/O overlay of 1631 * a file mapping. R/O MAP_PRIVATE mappings might still modify 1632 * underlying memory if ptrace is active, so this is only possible if 1633 * ptrace does not apply. Note that there is no mprotect() to upgrade 1634 * write permissions later. 1635 */ 1636 return flags & (VM_MAYSHARE | VM_MAYOVERLAY); 1637} 1638#endif 1639 1640#if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) 1641#define SECTION_IN_PAGE_FLAGS 1642#endif 1643 1644/* 1645 * The identification function is mainly used by the buddy allocator for 1646 * determining if two pages could be buddies. We are not really identifying 1647 * the zone since we could be using the section number id if we do not have 1648 * node id available in page flags. 1649 * We only guarantee that it will return the same value for two combinable 1650 * pages in a zone. 1651 */ 1652static inline int page_zone_id(struct page *page) 1653{ 1654 return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK; 1655} 1656 1657#ifdef NODE_NOT_IN_PAGE_FLAGS 1658int page_to_nid(const struct page *page); 1659#else 1660static inline int page_to_nid(const struct page *page) 1661{ 1662 return (PF_POISONED_CHECK(page)->flags >> NODES_PGSHIFT) & NODES_MASK; 1663} 1664#endif 1665 1666static inline int folio_nid(const struct folio *folio) 1667{ 1668 return page_to_nid(&folio->page); 1669} 1670 1671#ifdef CONFIG_NUMA_BALANCING 1672/* page access time bits needs to hold at least 4 seconds */ 1673#define PAGE_ACCESS_TIME_MIN_BITS 12 1674#if LAST_CPUPID_SHIFT < PAGE_ACCESS_TIME_MIN_BITS 1675#define PAGE_ACCESS_TIME_BUCKETS \ 1676 (PAGE_ACCESS_TIME_MIN_BITS - LAST_CPUPID_SHIFT) 1677#else 1678#define PAGE_ACCESS_TIME_BUCKETS 0 1679#endif 1680 1681#define PAGE_ACCESS_TIME_MASK \ 1682 (LAST_CPUPID_MASK << PAGE_ACCESS_TIME_BUCKETS) 1683 1684static inline int cpu_pid_to_cpupid(int cpu, int pid) 1685{ 1686 return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK); 1687} 1688 1689static inline int cpupid_to_pid(int cpupid) 1690{ 1691 return cpupid & LAST__PID_MASK; 1692} 1693 1694static inline int cpupid_to_cpu(int cpupid) 1695{ 1696 return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK; 1697} 1698 1699static inline int cpupid_to_nid(int cpupid) 1700{ 1701 return cpu_to_node(cpupid_to_cpu(cpupid)); 1702} 1703 1704static inline bool cpupid_pid_unset(int cpupid) 1705{ 1706 return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK); 1707} 1708 1709static inline bool cpupid_cpu_unset(int cpupid) 1710{ 1711 return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK); 1712} 1713 1714static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid) 1715{ 1716 return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid); 1717} 1718 1719#define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid) 1720#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS 1721static inline int folio_xchg_last_cpupid(struct folio *folio, int cpupid) 1722{ 1723 return xchg(&folio->_last_cpupid, cpupid & LAST_CPUPID_MASK); 1724} 1725 1726static inline int folio_last_cpupid(struct folio *folio) 1727{ 1728 return folio->_last_cpupid; 1729} 1730static inline void page_cpupid_reset_last(struct page *page) 1731{ 1732 page->_last_cpupid = -1 & LAST_CPUPID_MASK; 1733} 1734#else 1735static inline int folio_last_cpupid(struct folio *folio) 1736{ 1737 return (folio->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK; 1738} 1739 1740int folio_xchg_last_cpupid(struct folio *folio, int cpupid); 1741 1742static inline void page_cpupid_reset_last(struct page *page) 1743{ 1744 page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT; 1745} 1746#endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */ 1747 1748static inline int folio_xchg_access_time(struct folio *folio, int time) 1749{ 1750 int last_time; 1751 1752 last_time = folio_xchg_last_cpupid(folio, 1753 time >> PAGE_ACCESS_TIME_BUCKETS); 1754 return last_time << PAGE_ACCESS_TIME_BUCKETS; 1755} 1756 1757static inline void vma_set_access_pid_bit(struct vm_area_struct *vma) 1758{ 1759 unsigned int pid_bit; 1760 1761 pid_bit = hash_32(current->pid, ilog2(BITS_PER_LONG)); 1762 if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->pids_active[1])) { 1763 __set_bit(pid_bit, &vma->numab_state->pids_active[1]); 1764 } 1765} 1766#else /* !CONFIG_NUMA_BALANCING */ 1767static inline int folio_xchg_last_cpupid(struct folio *folio, int cpupid) 1768{ 1769 return folio_nid(folio); /* XXX */ 1770} 1771 1772static inline int folio_xchg_access_time(struct folio *folio, int time) 1773{ 1774 return 0; 1775} 1776 1777static inline int folio_last_cpupid(struct folio *folio) 1778{ 1779 return folio_nid(folio); /* XXX */ 1780} 1781 1782static inline int cpupid_to_nid(int cpupid) 1783{ 1784 return -1; 1785} 1786 1787static inline int cpupid_to_pid(int cpupid) 1788{ 1789 return -1; 1790} 1791 1792static inline int cpupid_to_cpu(int cpupid) 1793{ 1794 return -1; 1795} 1796 1797static inline int cpu_pid_to_cpupid(int nid, int pid) 1798{ 1799 return -1; 1800} 1801 1802static inline bool cpupid_pid_unset(int cpupid) 1803{ 1804 return true; 1805} 1806 1807static inline void page_cpupid_reset_last(struct page *page) 1808{ 1809} 1810 1811static inline bool cpupid_match_pid(struct task_struct *task, int cpupid) 1812{ 1813 return false; 1814} 1815 1816static inline void vma_set_access_pid_bit(struct vm_area_struct *vma) 1817{ 1818} 1819#endif /* CONFIG_NUMA_BALANCING */ 1820 1821#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) 1822 1823/* 1824 * KASAN per-page tags are stored xor'ed with 0xff. This allows to avoid 1825 * setting tags for all pages to native kernel tag value 0xff, as the default 1826 * value 0x00 maps to 0xff. 1827 */ 1828 1829static inline u8 page_kasan_tag(const struct page *page) 1830{ 1831 u8 tag = KASAN_TAG_KERNEL; 1832 1833 if (kasan_enabled()) { 1834 tag = (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK; 1835 tag ^= 0xff; 1836 } 1837 1838 return tag; 1839} 1840 1841static inline void page_kasan_tag_set(struct page *page, u8 tag) 1842{ 1843 unsigned long old_flags, flags; 1844 1845 if (!kasan_enabled()) 1846 return; 1847 1848 tag ^= 0xff; 1849 old_flags = READ_ONCE(page->flags); 1850 do { 1851 flags = old_flags; 1852 flags &= ~(KASAN_TAG_MASK << KASAN_TAG_PGSHIFT); 1853 flags |= (tag & KASAN_TAG_MASK) << KASAN_TAG_PGSHIFT; 1854 } while (unlikely(!try_cmpxchg(&page->flags, &old_flags, flags))); 1855} 1856 1857static inline void page_kasan_tag_reset(struct page *page) 1858{ 1859 if (kasan_enabled()) 1860 page_kasan_tag_set(page, KASAN_TAG_KERNEL); 1861} 1862 1863#else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */ 1864 1865static inline u8 page_kasan_tag(const struct page *page) 1866{ 1867 return 0xff; 1868} 1869 1870static inline void page_kasan_tag_set(struct page *page, u8 tag) { } 1871static inline void page_kasan_tag_reset(struct page *page) { } 1872 1873#endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */ 1874 1875static inline struct zone *page_zone(const struct page *page) 1876{ 1877 return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)]; 1878} 1879 1880static inline pg_data_t *page_pgdat(const struct page *page) 1881{ 1882 return NODE_DATA(page_to_nid(page)); 1883} 1884 1885static inline struct zone *folio_zone(const struct folio *folio) 1886{ 1887 return page_zone(&folio->page); 1888} 1889 1890static inline pg_data_t *folio_pgdat(const struct folio *folio) 1891{ 1892 return page_pgdat(&folio->page); 1893} 1894 1895#ifdef SECTION_IN_PAGE_FLAGS 1896static inline void set_page_section(struct page *page, unsigned long section) 1897{ 1898 page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT); 1899 page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT; 1900} 1901 1902static inline unsigned long page_to_section(const struct page *page) 1903{ 1904 return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; 1905} 1906#endif 1907 1908/** 1909 * folio_pfn - Return the Page Frame Number of a folio. 1910 * @folio: The folio. 1911 * 1912 * A folio may contain multiple pages. The pages have consecutive 1913 * Page Frame Numbers. 1914 * 1915 * Return: The Page Frame Number of the first page in the folio. 1916 */ 1917static inline unsigned long folio_pfn(struct folio *folio) 1918{ 1919 return page_to_pfn(&folio->page); 1920} 1921 1922static inline struct folio *pfn_folio(unsigned long pfn) 1923{ 1924 return page_folio(pfn_to_page(pfn)); 1925} 1926 1927/** 1928 * folio_maybe_dma_pinned - Report if a folio may be pinned for DMA. 1929 * @folio: The folio. 1930 * 1931 * This function checks if a folio has been pinned via a call to 1932 * a function in the pin_user_pages() family. 1933 * 1934 * For small folios, the return value is partially fuzzy: false is not fuzzy, 1935 * because it means "definitely not pinned for DMA", but true means "probably 1936 * pinned for DMA, but possibly a false positive due to having at least 1937 * GUP_PIN_COUNTING_BIAS worth of normal folio references". 1938 * 1939 * False positives are OK, because: a) it's unlikely for a folio to 1940 * get that many refcounts, and b) all the callers of this routine are 1941 * expected to be able to deal gracefully with a false positive. 1942 * 1943 * For large folios, the result will be exactly correct. That's because 1944 * we have more tracking data available: the _pincount field is used 1945 * instead of the GUP_PIN_COUNTING_BIAS scheme. 1946 * 1947 * For more information, please see Documentation/core-api/pin_user_pages.rst. 1948 * 1949 * Return: True, if it is likely that the page has been "dma-pinned". 1950 * False, if the page is definitely not dma-pinned. 1951 */ 1952static inline bool folio_maybe_dma_pinned(struct folio *folio) 1953{ 1954 if (folio_test_large(folio)) 1955 return atomic_read(&folio->_pincount) > 0; 1956 1957 /* 1958 * folio_ref_count() is signed. If that refcount overflows, then 1959 * folio_ref_count() returns a negative value, and callers will avoid 1960 * further incrementing the refcount. 1961 * 1962 * Here, for that overflow case, use the sign bit to count a little 1963 * bit higher via unsigned math, and thus still get an accurate result. 1964 */ 1965 return ((unsigned int)folio_ref_count(folio)) >= 1966 GUP_PIN_COUNTING_BIAS; 1967} 1968 1969static inline bool page_maybe_dma_pinned(struct page *page) 1970{ 1971 return folio_maybe_dma_pinned(page_folio(page)); 1972} 1973 1974/* 1975 * This should most likely only be called during fork() to see whether we 1976 * should break the cow immediately for an anon page on the src mm. 1977 * 1978 * The caller has to hold the PT lock and the vma->vm_mm->->write_protect_seq. 1979 */ 1980static inline bool folio_needs_cow_for_dma(struct vm_area_struct *vma, 1981 struct folio *folio) 1982{ 1983 VM_BUG_ON(!(raw_read_seqcount(&vma->vm_mm->write_protect_seq) & 1)); 1984 1985 if (!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags)) 1986 return false; 1987 1988 return folio_maybe_dma_pinned(folio); 1989} 1990 1991/** 1992 * is_zero_page - Query if a page is a zero page 1993 * @page: The page to query 1994 * 1995 * This returns true if @page is one of the permanent zero pages. 1996 */ 1997static inline bool is_zero_page(const struct page *page) 1998{ 1999 return is_zero_pfn(page_to_pfn(page)); 2000} 2001 2002/** 2003 * is_zero_folio - Query if a folio is a zero page 2004 * @folio: The folio to query 2005 * 2006 * This returns true if @folio is one of the permanent zero pages. 2007 */ 2008static inline bool is_zero_folio(const struct folio *folio) 2009{ 2010 return is_zero_page(&folio->page); 2011} 2012 2013/* MIGRATE_CMA and ZONE_MOVABLE do not allow pin folios */ 2014#ifdef CONFIG_MIGRATION 2015static inline bool folio_is_longterm_pinnable(struct folio *folio) 2016{ 2017#ifdef CONFIG_CMA 2018 int mt = folio_migratetype(folio); 2019 2020 if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE) 2021 return false; 2022#endif 2023 /* The zero page can be "pinned" but gets special handling. */ 2024 if (is_zero_folio(folio)) 2025 return true; 2026 2027 /* Coherent device memory must always allow eviction. */ 2028 if (folio_is_device_coherent(folio)) 2029 return false; 2030 2031 /* Otherwise, non-movable zone folios can be pinned. */ 2032 return !folio_is_zone_movable(folio); 2033 2034} 2035#else 2036static inline bool folio_is_longterm_pinnable(struct folio *folio) 2037{ 2038 return true; 2039} 2040#endif 2041 2042static inline void set_page_zone(struct page *page, enum zone_type zone) 2043{ 2044 page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); 2045 page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; 2046} 2047 2048static inline void set_page_node(struct page *page, unsigned long node) 2049{ 2050 page->flags &= ~(NODES_MASK << NODES_PGSHIFT); 2051 page->flags |= (node & NODES_MASK) << NODES_PGSHIFT; 2052} 2053 2054static inline void set_page_links(struct page *page, enum zone_type zone, 2055 unsigned long node, unsigned long pfn) 2056{ 2057 set_page_zone(page, zone); 2058 set_page_node(page, node); 2059#ifdef SECTION_IN_PAGE_FLAGS 2060 set_page_section(page, pfn_to_section_nr(pfn)); 2061#endif 2062} 2063 2064/** 2065 * folio_nr_pages - The number of pages in the folio. 2066 * @folio: The folio. 2067 * 2068 * Return: A positive power of two. 2069 */ 2070static inline long folio_nr_pages(struct folio *folio) 2071{ 2072 if (!folio_test_large(folio)) 2073 return 1; 2074#ifdef CONFIG_64BIT 2075 return folio->_folio_nr_pages; 2076#else 2077 return 1L << (folio->_flags_1 & 0xff); 2078#endif 2079} 2080 2081/* Only hugetlbfs can allocate folios larger than MAX_ORDER */ 2082#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE 2083#define MAX_FOLIO_NR_PAGES (1UL << PUD_ORDER) 2084#else 2085#define MAX_FOLIO_NR_PAGES MAX_ORDER_NR_PAGES 2086#endif 2087 2088/* 2089 * compound_nr() returns the number of pages in this potentially compound 2090 * page. compound_nr() can be called on a tail page, and is defined to 2091 * return 1 in that case. 2092 */ 2093static inline unsigned long compound_nr(struct page *page) 2094{ 2095 struct folio *folio = (struct folio *)page; 2096 2097 if (!test_bit(PG_head, &folio->flags)) 2098 return 1; 2099#ifdef CONFIG_64BIT 2100 return folio->_folio_nr_pages; 2101#else 2102 return 1L << (folio->_flags_1 & 0xff); 2103#endif 2104} 2105 2106/** 2107 * thp_nr_pages - The number of regular pages in this huge page. 2108 * @page: The head page of a huge page. 2109 */ 2110static inline int thp_nr_pages(struct page *page) 2111{ 2112 return folio_nr_pages((struct folio *)page); 2113} 2114 2115/** 2116 * folio_next - Move to the next physical folio. 2117 * @folio: The folio we're currently operating on. 2118 * 2119 * If you have physically contiguous memory which may span more than 2120 * one folio (eg a &struct bio_vec), use this function to move from one 2121 * folio to the next. Do not use it if the memory is only virtually 2122 * contiguous as the folios are almost certainly not adjacent to each 2123 * other. This is the folio equivalent to writing ``page++``. 2124 * 2125 * Context: We assume that the folios are refcounted and/or locked at a 2126 * higher level and do not adjust the reference counts. 2127 * Return: The next struct folio. 2128 */ 2129static inline struct folio *folio_next(struct folio *folio) 2130{ 2131 return (struct folio *)folio_page(folio, folio_nr_pages(folio)); 2132} 2133 2134/** 2135 * folio_shift - The size of the memory described by this folio. 2136 * @folio: The folio. 2137 * 2138 * A folio represents a number of bytes which is a power-of-two in size. 2139 * This function tells you which power-of-two the folio is. See also 2140 * folio_size() and folio_order(). 2141 * 2142 * Context: The caller should have a reference on the folio to prevent 2143 * it from being split. It is not necessary for the folio to be locked. 2144 * Return: The base-2 logarithm of the size of this folio. 2145 */ 2146static inline unsigned int folio_shift(struct folio *folio) 2147{ 2148 return PAGE_SHIFT + folio_order(folio); 2149} 2150 2151/** 2152 * folio_size - The number of bytes in a folio. 2153 * @folio: The folio. 2154 * 2155 * Context: The caller should have a reference on the folio to prevent 2156 * it from being split. It is not necessary for the folio to be locked. 2157 * Return: The number of bytes in this folio. 2158 */ 2159static inline size_t folio_size(struct folio *folio) 2160{ 2161 return PAGE_SIZE << folio_order(folio); 2162} 2163 2164/** 2165 * folio_estimated_sharers - Estimate the number of sharers of a folio. 2166 * @folio: The folio. 2167 * 2168 * folio_estimated_sharers() aims to serve as a function to efficiently 2169 * estimate the number of processes sharing a folio. This is done by 2170 * looking at the precise mapcount of the first subpage in the folio, and 2171 * assuming the other subpages are the same. This may not be true for large 2172 * folios. If you want exact mapcounts for exact calculations, look at 2173 * page_mapcount() or folio_total_mapcount(). 2174 * 2175 * Return: The estimated number of processes sharing a folio. 2176 */ 2177static inline int folio_estimated_sharers(struct folio *folio) 2178{ 2179 return page_mapcount(folio_page(folio, 0)); 2180} 2181 2182#ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE 2183static inline int arch_make_page_accessible(struct page *page) 2184{ 2185 return 0; 2186} 2187#endif 2188 2189#ifndef HAVE_ARCH_MAKE_FOLIO_ACCESSIBLE 2190static inline int arch_make_folio_accessible(struct folio *folio) 2191{ 2192 int ret; 2193 long i, nr = folio_nr_pages(folio); 2194 2195 for (i = 0; i < nr; i++) { 2196 ret = arch_make_page_accessible(folio_page(folio, i)); 2197 if (ret) 2198 break; 2199 } 2200 2201 return ret; 2202} 2203#endif 2204 2205/* 2206 * Some inline functions in vmstat.h depend on page_zone() 2207 */ 2208#include <linux/vmstat.h> 2209 2210#if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) 2211#define HASHED_PAGE_VIRTUAL 2212#endif 2213 2214#if defined(WANT_PAGE_VIRTUAL) 2215static inline void *page_address(const struct page *page) 2216{ 2217 return page->virtual; 2218} 2219static inline void set_page_address(struct page *page, void *address) 2220{ 2221 page->virtual = address; 2222} 2223#define page_address_init() do { } while(0) 2224#endif 2225 2226#if defined(HASHED_PAGE_VIRTUAL) 2227void *page_address(const struct page *page); 2228void set_page_address(struct page *page, void *virtual); 2229void page_address_init(void); 2230#endif 2231 2232static __always_inline void *lowmem_page_address(const struct page *page) 2233{ 2234 return page_to_virt(page); 2235} 2236 2237#if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL) 2238#define page_address(page) lowmem_page_address(page) 2239#define set_page_address(page, address) do { } while(0) 2240#define page_address_init() do { } while(0) 2241#endif 2242 2243static inline void *folio_address(const struct folio *folio) 2244{ 2245 return page_address(&folio->page); 2246} 2247 2248extern pgoff_t __page_file_index(struct page *page); 2249 2250/* 2251 * Return the pagecache index of the passed page. Regular pagecache pages 2252 * use ->index whereas swapcache pages use swp_offset(->private) 2253 */ 2254static inline pgoff_t page_index(struct page *page) 2255{ 2256 if (unlikely(PageSwapCache(page))) 2257 return __page_file_index(page); 2258 return page->index; 2259} 2260 2261/* 2262 * Return true only if the page has been allocated with 2263 * ALLOC_NO_WATERMARKS and the low watermark was not 2264 * met implying that the system is under some pressure. 2265 */ 2266static inline bool page_is_pfmemalloc(const struct page *page) 2267{ 2268 /* 2269 * lru.next has bit 1 set if the page is allocated from the 2270 * pfmemalloc reserves. Callers may simply overwrite it if 2271 * they do not need to preserve that information. 2272 */ 2273 return (uintptr_t)page->lru.next & BIT(1); 2274} 2275 2276/* 2277 * Return true only if the folio has been allocated with 2278 * ALLOC_NO_WATERMARKS and the low watermark was not 2279 * met implying that the system is under some pressure. 2280 */ 2281static inline bool folio_is_pfmemalloc(const struct folio *folio) 2282{ 2283 /* 2284 * lru.next has bit 1 set if the page is allocated from the 2285 * pfmemalloc reserves. Callers may simply overwrite it if 2286 * they do not need to preserve that information. 2287 */ 2288 return (uintptr_t)folio->lru.next & BIT(1); 2289} 2290 2291/* 2292 * Only to be called by the page allocator on a freshly allocated 2293 * page. 2294 */ 2295static inline void set_page_pfmemalloc(struct page *page) 2296{ 2297 page->lru.next = (void *)BIT(1); 2298} 2299 2300static inline void clear_page_pfmemalloc(struct page *page) 2301{ 2302 page->lru.next = NULL; 2303} 2304 2305/* 2306 * Can be called by the pagefault handler when it gets a VM_FAULT_OOM. 2307 */ 2308extern void pagefault_out_of_memory(void); 2309 2310#define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) 2311#define offset_in_thp(page, p) ((unsigned long)(p) & (thp_size(page) - 1)) 2312#define offset_in_folio(folio, p) ((unsigned long)(p) & (folio_size(folio) - 1)) 2313 2314/* 2315 * Parameter block passed down to zap_pte_range in exceptional cases. 2316 */ 2317struct zap_details { 2318 struct folio *single_folio; /* Locked folio to be unmapped */ 2319 bool even_cows; /* Zap COWed private pages too? */ 2320 zap_flags_t zap_flags; /* Extra flags for zapping */ 2321}; 2322 2323/* 2324 * Whether to drop the pte markers, for example, the uffd-wp information for 2325 * file-backed memory. This should only be specified when we will completely 2326 * drop the page in the mm, either by truncation or unmapping of the vma. By 2327 * default, the flag is not set. 2328 */ 2329#define ZAP_FLAG_DROP_MARKER ((__force zap_flags_t) BIT(0)) 2330/* Set in unmap_vmas() to indicate a final unmap call. Only used by hugetlb */ 2331#define ZAP_FLAG_UNMAP ((__force zap_flags_t) BIT(1)) 2332 2333#ifdef CONFIG_SCHED_MM_CID 2334void sched_mm_cid_before_execve(struct task_struct *t); 2335void sched_mm_cid_after_execve(struct task_struct *t); 2336void sched_mm_cid_fork(struct task_struct *t); 2337void sched_mm_cid_exit_signals(struct task_struct *t); 2338static inline int task_mm_cid(struct task_struct *t) 2339{ 2340 return t->mm_cid; 2341} 2342#else 2343static inline void sched_mm_cid_before_execve(struct task_struct *t) { } 2344static inline void sched_mm_cid_after_execve(struct task_struct *t) { } 2345static inline void sched_mm_cid_fork(struct task_struct *t) { } 2346static inline void sched_mm_cid_exit_signals(struct task_struct *t) { } 2347static inline int task_mm_cid(struct task_struct *t) 2348{ 2349 /* 2350 * Use the processor id as a fall-back when the mm cid feature is 2351 * disabled. This provides functional per-cpu data structure accesses 2352 * in user-space, althrough it won't provide the memory usage benefits. 2353 */ 2354 return raw_smp_processor_id(); 2355} 2356#endif 2357 2358#ifdef CONFIG_MMU 2359extern bool can_do_mlock(void); 2360#else 2361static inline bool can_do_mlock(void) { return false; } 2362#endif 2363extern int user_shm_lock(size_t, struct ucounts *); 2364extern void user_shm_unlock(size_t, struct ucounts *); 2365 2366struct folio *vm_normal_folio(struct vm_area_struct *vma, unsigned long addr, 2367 pte_t pte); 2368struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, 2369 pte_t pte); 2370struct folio *vm_normal_folio_pmd(struct vm_area_struct *vma, 2371 unsigned long addr, pmd_t pmd); 2372struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr, 2373 pmd_t pmd); 2374 2375void zap_vma_ptes(struct vm_area_struct *vma, unsigned long address, 2376 unsigned long size); 2377void zap_page_range_single(struct vm_area_struct *vma, unsigned long address, 2378 unsigned long size, struct zap_details *details); 2379static inline void zap_vma_pages(struct vm_area_struct *vma) 2380{ 2381 zap_page_range_single(vma, vma->vm_start, 2382 vma->vm_end - vma->vm_start, NULL); 2383} 2384void unmap_vmas(struct mmu_gather *tlb, struct ma_state *mas, 2385 struct vm_area_struct *start_vma, unsigned long start, 2386 unsigned long end, unsigned long tree_end, bool mm_wr_locked); 2387 2388struct mmu_notifier_range; 2389 2390void free_pgd_range(struct mmu_gather *tlb, unsigned long addr, 2391 unsigned long end, unsigned long floor, unsigned long ceiling); 2392int 2393copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma); 2394int follow_pte(struct mm_struct *mm, unsigned long address, 2395 pte_t **ptepp, spinlock_t **ptlp); 2396int follow_pfn(struct vm_area_struct *vma, unsigned long address, 2397 unsigned long *pfn); 2398int follow_phys(struct vm_area_struct *vma, unsigned long address, 2399 unsigned int flags, unsigned long *prot, resource_size_t *phys); 2400int generic_access_phys(struct vm_area_struct *vma, unsigned long addr, 2401 void *buf, int len, int write); 2402 2403extern void truncate_pagecache(struct inode *inode, loff_t new); 2404extern void truncate_setsize(struct inode *inode, loff_t newsize); 2405void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to); 2406void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end); 2407int generic_error_remove_folio(struct address_space *mapping, 2408 struct folio *folio); 2409 2410struct vm_area_struct *lock_mm_and_find_vma(struct mm_struct *mm, 2411 unsigned long address, struct pt_regs *regs); 2412 2413#ifdef CONFIG_MMU 2414extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma, 2415 unsigned long address, unsigned int flags, 2416 struct pt_regs *regs); 2417extern int fixup_user_fault(struct mm_struct *mm, 2418 unsigned long address, unsigned int fault_flags, 2419 bool *unlocked); 2420void unmap_mapping_pages(struct address_space *mapping, 2421 pgoff_t start, pgoff_t nr, bool even_cows); 2422void unmap_mapping_range(struct address_space *mapping, 2423 loff_t const holebegin, loff_t const holelen, int even_cows); 2424#else 2425static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma, 2426 unsigned long address, unsigned int flags, 2427 struct pt_regs *regs) 2428{ 2429 /* should never happen if there's no MMU */ 2430 BUG(); 2431 return VM_FAULT_SIGBUS; 2432} 2433static inline int fixup_user_fault(struct mm_struct *mm, unsigned long address, 2434 unsigned int fault_flags, bool *unlocked) 2435{ 2436 /* should never happen if there's no MMU */ 2437 BUG(); 2438 return -EFAULT; 2439} 2440static inline void unmap_mapping_pages(struct address_space *mapping, 2441 pgoff_t start, pgoff_t nr, bool even_cows) { } 2442static inline void unmap_mapping_range(struct address_space *mapping, 2443 loff_t const holebegin, loff_t const holelen, int even_cows) { } 2444#endif 2445 2446static inline void unmap_shared_mapping_range(struct address_space *mapping, 2447 loff_t const holebegin, loff_t const holelen) 2448{ 2449 unmap_mapping_range(mapping, holebegin, holelen, 0); 2450} 2451 2452static inline struct vm_area_struct *vma_lookup(struct mm_struct *mm, 2453 unsigned long addr); 2454 2455extern int access_process_vm(struct task_struct *tsk, unsigned long addr, 2456 void *buf, int len, unsigned int gup_flags); 2457extern int access_remote_vm(struct mm_struct *mm, unsigned long addr, 2458 void *buf, int len, unsigned int gup_flags); 2459 2460long get_user_pages_remote(struct mm_struct *mm, 2461 unsigned long start, unsigned long nr_pages, 2462 unsigned int gup_flags, struct page **pages, 2463 int *locked); 2464long pin_user_pages_remote(struct mm_struct *mm, 2465 unsigned long start, unsigned long nr_pages, 2466 unsigned int gup_flags, struct page **pages, 2467 int *locked); 2468 2469/* 2470 * Retrieves a single page alongside its VMA. Does not support FOLL_NOWAIT. 2471 */ 2472static inline struct page *get_user_page_vma_remote(struct mm_struct *mm, 2473 unsigned long addr, 2474 int gup_flags, 2475 struct vm_area_struct **vmap) 2476{ 2477 struct page *page; 2478 struct vm_area_struct *vma; 2479 int got; 2480 2481 if (WARN_ON_ONCE(unlikely(gup_flags & FOLL_NOWAIT))) 2482 return ERR_PTR(-EINVAL); 2483 2484 got = get_user_pages_remote(mm, addr, 1, gup_flags, &page, NULL); 2485 2486 if (got < 0) 2487 return ERR_PTR(got); 2488 2489 vma = vma_lookup(mm, addr); 2490 if (WARN_ON_ONCE(!vma)) { 2491 put_page(page); 2492 return ERR_PTR(-EINVAL); 2493 } 2494 2495 *vmap = vma; 2496 return page; 2497} 2498 2499long get_user_pages(unsigned long start, unsigned long nr_pages, 2500 unsigned int gup_flags, struct page **pages); 2501long pin_user_pages(unsigned long start, unsigned long nr_pages, 2502 unsigned int gup_flags, struct page **pages); 2503long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, 2504 struct page **pages, unsigned int gup_flags); 2505long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages, 2506 struct page **pages, unsigned int gup_flags); 2507 2508int get_user_pages_fast(unsigned long start, int nr_pages, 2509 unsigned int gup_flags, struct page **pages); 2510int pin_user_pages_fast(unsigned long start, int nr_pages, 2511 unsigned int gup_flags, struct page **pages); 2512void folio_add_pin(struct folio *folio); 2513 2514int account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc); 2515int __account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc, 2516 struct task_struct *task, bool bypass_rlim); 2517 2518struct kvec; 2519struct page *get_dump_page(unsigned long addr); 2520 2521bool folio_mark_dirty(struct folio *folio); 2522bool set_page_dirty(struct page *page); 2523int set_page_dirty_lock(struct page *page); 2524 2525int get_cmdline(struct task_struct *task, char *buffer, int buflen); 2526 2527extern unsigned long move_page_tables(struct vm_area_struct *vma, 2528 unsigned long old_addr, struct vm_area_struct *new_vma, 2529 unsigned long new_addr, unsigned long len, 2530 bool need_rmap_locks, bool for_stack); 2531 2532/* 2533 * Flags used by change_protection(). For now we make it a bitmap so 2534 * that we can pass in multiple flags just like parameters. However 2535 * for now all the callers are only use one of the flags at the same 2536 * time. 2537 */ 2538/* 2539 * Whether we should manually check if we can map individual PTEs writable, 2540 * because something (e.g., COW, uffd-wp) blocks that from happening for all 2541 * PTEs automatically in a writable mapping. 2542 */ 2543#define MM_CP_TRY_CHANGE_WRITABLE (1UL << 0) 2544/* Whether this protection change is for NUMA hints */ 2545#define MM_CP_PROT_NUMA (1UL << 1) 2546/* Whether this change is for write protecting */ 2547#define MM_CP_UFFD_WP (1UL << 2) /* do wp */ 2548#define MM_CP_UFFD_WP_RESOLVE (1UL << 3) /* Resolve wp */ 2549#define MM_CP_UFFD_WP_ALL (MM_CP_UFFD_WP | \ 2550 MM_CP_UFFD_WP_RESOLVE) 2551 2552bool vma_needs_dirty_tracking(struct vm_area_struct *vma); 2553int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot); 2554static inline bool vma_wants_manual_pte_write_upgrade(struct vm_area_struct *vma) 2555{ 2556 /* 2557 * We want to check manually if we can change individual PTEs writable 2558 * if we can't do that automatically for all PTEs in a mapping. For 2559 * private mappings, that's always the case when we have write 2560 * permissions as we properly have to handle COW. 2561 */ 2562 if (vma->vm_flags & VM_SHARED) 2563 return vma_wants_writenotify(vma, vma->vm_page_prot); 2564 return !!(vma->vm_flags & VM_WRITE); 2565 2566} 2567bool can_change_pte_writable(struct vm_area_struct *vma, unsigned long addr, 2568 pte_t pte); 2569extern long change_protection(struct mmu_gather *tlb, 2570 struct vm_area_struct *vma, unsigned long start, 2571 unsigned long end, unsigned long cp_flags); 2572extern int mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb, 2573 struct vm_area_struct *vma, struct vm_area_struct **pprev, 2574 unsigned long start, unsigned long end, unsigned long newflags); 2575 2576/* 2577 * doesn't attempt to fault and will return short. 2578 */ 2579int get_user_pages_fast_only(unsigned long start, int nr_pages, 2580 unsigned int gup_flags, struct page **pages); 2581 2582static inline bool get_user_page_fast_only(unsigned long addr, 2583 unsigned int gup_flags, struct page **pagep) 2584{ 2585 return get_user_pages_fast_only(addr, 1, gup_flags, pagep) == 1; 2586} 2587/* 2588 * per-process(per-mm_struct) statistics. 2589 */ 2590static inline unsigned long get_mm_counter(struct mm_struct *mm, int member) 2591{ 2592 return percpu_counter_read_positive(&mm->rss_stat[member]); 2593} 2594 2595void mm_trace_rss_stat(struct mm_struct *mm, int member); 2596 2597static inline void add_mm_counter(struct mm_struct *mm, int member, long value) 2598{ 2599 percpu_counter_add(&mm->rss_stat[member], value); 2600 2601 mm_trace_rss_stat(mm, member); 2602} 2603 2604static inline void inc_mm_counter(struct mm_struct *mm, int member) 2605{ 2606 percpu_counter_inc(&mm->rss_stat[member]); 2607 2608 mm_trace_rss_stat(mm, member); 2609} 2610 2611static inline void dec_mm_counter(struct mm_struct *mm, int member) 2612{ 2613 percpu_counter_dec(&mm->rss_stat[member]); 2614 2615 mm_trace_rss_stat(mm, member); 2616} 2617 2618/* Optimized variant when folio is already known not to be anon */ 2619static inline int mm_counter_file(struct folio *folio) 2620{ 2621 if (folio_test_swapbacked(folio)) 2622 return MM_SHMEMPAGES; 2623 return MM_FILEPAGES; 2624} 2625 2626static inline int mm_counter(struct folio *folio) 2627{ 2628 if (folio_test_anon(folio)) 2629 return MM_ANONPAGES; 2630 return mm_counter_file(folio); 2631} 2632 2633static inline unsigned long get_mm_rss(struct mm_struct *mm) 2634{ 2635 return get_mm_counter(mm, MM_FILEPAGES) + 2636 get_mm_counter(mm, MM_ANONPAGES) + 2637 get_mm_counter(mm, MM_SHMEMPAGES); 2638} 2639 2640static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm) 2641{ 2642 return max(mm->hiwater_rss, get_mm_rss(mm)); 2643} 2644 2645static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm) 2646{ 2647 return max(mm->hiwater_vm, mm->total_vm); 2648} 2649 2650static inline void update_hiwater_rss(struct mm_struct *mm) 2651{ 2652 unsigned long _rss = get_mm_rss(mm); 2653 2654 if ((mm)->hiwater_rss < _rss) 2655 (mm)->hiwater_rss = _rss; 2656} 2657 2658static inline void update_hiwater_vm(struct mm_struct *mm) 2659{ 2660 if (mm->hiwater_vm < mm->total_vm) 2661 mm->hiwater_vm = mm->total_vm; 2662} 2663 2664static inline void reset_mm_hiwater_rss(struct mm_struct *mm) 2665{ 2666 mm->hiwater_rss = get_mm_rss(mm); 2667} 2668 2669static inline void setmax_mm_hiwater_rss(unsigned long *maxrss, 2670 struct mm_struct *mm) 2671{ 2672 unsigned long hiwater_rss = get_mm_hiwater_rss(mm); 2673 2674 if (*maxrss < hiwater_rss) 2675 *maxrss = hiwater_rss; 2676} 2677 2678#ifndef CONFIG_ARCH_HAS_PTE_SPECIAL 2679static inline int pte_special(pte_t pte) 2680{ 2681 return 0; 2682} 2683 2684static inline pte_t pte_mkspecial(pte_t pte) 2685{ 2686 return pte; 2687} 2688#endif 2689 2690#ifndef CONFIG_ARCH_HAS_PTE_DEVMAP 2691static inline int pte_devmap(pte_t pte) 2692{ 2693 return 0; 2694} 2695#endif 2696 2697extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr, 2698 spinlock_t **ptl); 2699static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, 2700 spinlock_t **ptl) 2701{ 2702 pte_t *ptep; 2703 __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl)); 2704 return ptep; 2705} 2706 2707#ifdef __PAGETABLE_P4D_FOLDED 2708static inline int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, 2709 unsigned long address) 2710{ 2711 return 0; 2712} 2713#else 2714int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); 2715#endif 2716 2717#if defined(__PAGETABLE_PUD_FOLDED) || !defined(CONFIG_MMU) 2718static inline int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, 2719 unsigned long address) 2720{ 2721 return 0; 2722} 2723static inline void mm_inc_nr_puds(struct mm_struct *mm) {} 2724static inline void mm_dec_nr_puds(struct mm_struct *mm) {} 2725 2726#else 2727int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address); 2728 2729static inline void mm_inc_nr_puds(struct mm_struct *mm) 2730{ 2731 if (mm_pud_folded(mm)) 2732 return; 2733 atomic_long_add(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes); 2734} 2735 2736static inline void mm_dec_nr_puds(struct mm_struct *mm) 2737{ 2738 if (mm_pud_folded(mm)) 2739 return; 2740 atomic_long_sub(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes); 2741} 2742#endif 2743 2744#if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU) 2745static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud, 2746 unsigned long address) 2747{ 2748 return 0; 2749} 2750 2751static inline void mm_inc_nr_pmds(struct mm_struct *mm) {} 2752static inline void mm_dec_nr_pmds(struct mm_struct *mm) {} 2753 2754#else 2755int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); 2756 2757static inline void mm_inc_nr_pmds(struct mm_struct *mm) 2758{ 2759 if (mm_pmd_folded(mm)) 2760 return; 2761 atomic_long_add(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes); 2762} 2763 2764static inline void mm_dec_nr_pmds(struct mm_struct *mm) 2765{ 2766 if (mm_pmd_folded(mm)) 2767 return; 2768 atomic_long_sub(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes); 2769} 2770#endif 2771 2772#ifdef CONFIG_MMU 2773static inline void mm_pgtables_bytes_init(struct mm_struct *mm) 2774{ 2775 atomic_long_set(&mm->pgtables_bytes, 0); 2776} 2777 2778static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm) 2779{ 2780 return atomic_long_read(&mm->pgtables_bytes); 2781} 2782 2783static inline void mm_inc_nr_ptes(struct mm_struct *mm) 2784{ 2785 atomic_long_add(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes); 2786} 2787 2788static inline void mm_dec_nr_ptes(struct mm_struct *mm) 2789{ 2790 atomic_long_sub(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes); 2791} 2792#else 2793 2794static inline void mm_pgtables_bytes_init(struct mm_struct *mm) {} 2795static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm) 2796{ 2797 return 0; 2798} 2799 2800static inline void mm_inc_nr_ptes(struct mm_struct *mm) {} 2801static inline void mm_dec_nr_ptes(struct mm_struct *mm) {} 2802#endif 2803 2804int __pte_alloc(struct mm_struct *mm, pmd_t *pmd); 2805int __pte_alloc_kernel(pmd_t *pmd); 2806 2807#if defined(CONFIG_MMU) 2808 2809static inline p4d_t *p4d_alloc(struct mm_struct *mm, pgd_t *pgd, 2810 unsigned long address) 2811{ 2812 return (unlikely(pgd_none(*pgd)) && __p4d_alloc(mm, pgd, address)) ? 2813 NULL : p4d_offset(pgd, address); 2814} 2815 2816static inline pud_t *pud_alloc(struct mm_struct *mm, p4d_t *p4d, 2817 unsigned long address) 2818{ 2819 return (unlikely(p4d_none(*p4d)) && __pud_alloc(mm, p4d, address)) ? 2820 NULL : pud_offset(p4d, address); 2821} 2822 2823static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) 2824{ 2825 return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))? 2826 NULL: pmd_offset(pud, address); 2827} 2828#endif /* CONFIG_MMU */ 2829 2830static inline struct ptdesc *virt_to_ptdesc(const void *x) 2831{ 2832 return page_ptdesc(virt_to_page(x)); 2833} 2834 2835static inline void *ptdesc_to_virt(const struct ptdesc *pt) 2836{ 2837 return page_to_virt(ptdesc_page(pt)); 2838} 2839 2840static inline void *ptdesc_address(const struct ptdesc *pt) 2841{ 2842 return folio_address(ptdesc_folio(pt)); 2843} 2844 2845static inline bool pagetable_is_reserved(struct ptdesc *pt) 2846{ 2847 return folio_test_reserved(ptdesc_folio(pt)); 2848} 2849 2850/** 2851 * pagetable_alloc - Allocate pagetables 2852 * @gfp: GFP flags 2853 * @order: desired pagetable order 2854 * 2855 * pagetable_alloc allocates memory for page tables as well as a page table 2856 * descriptor to describe that memory. 2857 * 2858 * Return: The ptdesc describing the allocated page tables. 2859 */ 2860static inline struct ptdesc *pagetable_alloc(gfp_t gfp, unsigned int order) 2861{ 2862 struct page *page = alloc_pages(gfp | __GFP_COMP, order); 2863 2864 return page_ptdesc(page); 2865} 2866 2867/** 2868 * pagetable_free - Free pagetables 2869 * @pt: The page table descriptor 2870 * 2871 * pagetable_free frees the memory of all page tables described by a page 2872 * table descriptor and the memory for the descriptor itself. 2873 */ 2874static inline void pagetable_free(struct ptdesc *pt) 2875{ 2876 struct page *page = ptdesc_page(pt); 2877 2878 __free_pages(page, compound_order(page)); 2879} 2880 2881#if USE_SPLIT_PTE_PTLOCKS 2882#if ALLOC_SPLIT_PTLOCKS 2883void __init ptlock_cache_init(void); 2884bool ptlock_alloc(struct ptdesc *ptdesc); 2885void ptlock_free(struct ptdesc *ptdesc); 2886 2887static inline spinlock_t *ptlock_ptr(struct ptdesc *ptdesc) 2888{ 2889 return ptdesc->ptl; 2890} 2891#else /* ALLOC_SPLIT_PTLOCKS */ 2892static inline void ptlock_cache_init(void) 2893{ 2894} 2895 2896static inline bool ptlock_alloc(struct ptdesc *ptdesc) 2897{ 2898 return true; 2899} 2900 2901static inline void ptlock_free(struct ptdesc *ptdesc) 2902{ 2903} 2904 2905static inline spinlock_t *ptlock_ptr(struct ptdesc *ptdesc) 2906{ 2907 return &ptdesc->ptl; 2908} 2909#endif /* ALLOC_SPLIT_PTLOCKS */ 2910 2911static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd) 2912{ 2913 return ptlock_ptr(page_ptdesc(pmd_page(*pmd))); 2914} 2915 2916static inline bool ptlock_init(struct ptdesc *ptdesc) 2917{ 2918 /* 2919 * prep_new_page() initialize page->private (and therefore page->ptl) 2920 * with 0. Make sure nobody took it in use in between. 2921 * 2922 * It can happen if arch try to use slab for page table allocation: 2923 * slab code uses page->slab_cache, which share storage with page->ptl. 2924 */ 2925 VM_BUG_ON_PAGE(*(unsigned long *)&ptdesc->ptl, ptdesc_page(ptdesc)); 2926 if (!ptlock_alloc(ptdesc)) 2927 return false; 2928 spin_lock_init(ptlock_ptr(ptdesc)); 2929 return true; 2930} 2931 2932#else /* !USE_SPLIT_PTE_PTLOCKS */ 2933/* 2934 * We use mm->page_table_lock to guard all pagetable pages of the mm. 2935 */ 2936static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd) 2937{ 2938 return &mm->page_table_lock; 2939} 2940static inline void ptlock_cache_init(void) {} 2941static inline bool ptlock_init(struct ptdesc *ptdesc) { return true; } 2942static inline void ptlock_free(struct ptdesc *ptdesc) {} 2943#endif /* USE_SPLIT_PTE_PTLOCKS */ 2944 2945static inline bool pagetable_pte_ctor(struct ptdesc *ptdesc) 2946{ 2947 struct folio *folio = ptdesc_folio(ptdesc); 2948 2949 if (!ptlock_init(ptdesc)) 2950 return false; 2951 __folio_set_pgtable(folio); 2952 lruvec_stat_add_folio(folio, NR_PAGETABLE); 2953 return true; 2954} 2955 2956static inline void pagetable_pte_dtor(struct ptdesc *ptdesc) 2957{ 2958 struct folio *folio = ptdesc_folio(ptdesc); 2959 2960 ptlock_free(ptdesc); 2961 __folio_clear_pgtable(folio); 2962 lruvec_stat_sub_folio(folio, NR_PAGETABLE); 2963} 2964 2965pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp); 2966static inline pte_t *pte_offset_map(pmd_t *pmd, unsigned long addr) 2967{ 2968 return __pte_offset_map(pmd, addr, NULL); 2969} 2970 2971pte_t *__pte_offset_map_lock(struct mm_struct *mm, pmd_t *pmd, 2972 unsigned long addr, spinlock_t **ptlp); 2973static inline pte_t *pte_offset_map_lock(struct mm_struct *mm, pmd_t *pmd, 2974 unsigned long addr, spinlock_t **ptlp) 2975{ 2976 pte_t *pte; 2977 2978 __cond_lock(*ptlp, pte = __pte_offset_map_lock(mm, pmd, addr, ptlp)); 2979 return pte; 2980} 2981 2982pte_t *pte_offset_map_nolock(struct mm_struct *mm, pmd_t *pmd, 2983 unsigned long addr, spinlock_t **ptlp); 2984 2985#define pte_unmap_unlock(pte, ptl) do { \ 2986 spin_unlock(ptl); \ 2987 pte_unmap(pte); \ 2988} while (0) 2989 2990#define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd)) 2991 2992#define pte_alloc_map(mm, pmd, address) \ 2993 (pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address)) 2994 2995#define pte_alloc_map_lock(mm, pmd, address, ptlp) \ 2996 (pte_alloc(mm, pmd) ? \ 2997 NULL : pte_offset_map_lock(mm, pmd, address, ptlp)) 2998 2999#define pte_alloc_kernel(pmd, address) \ 3000 ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \ 3001 NULL: pte_offset_kernel(pmd, address)) 3002 3003#if USE_SPLIT_PMD_PTLOCKS 3004 3005static inline struct page *pmd_pgtable_page(pmd_t *pmd) 3006{ 3007 unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); 3008 return virt_to_page((void *)((unsigned long) pmd & mask)); 3009} 3010 3011static inline struct ptdesc *pmd_ptdesc(pmd_t *pmd) 3012{ 3013 return page_ptdesc(pmd_pgtable_page(pmd)); 3014} 3015 3016static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) 3017{ 3018 return ptlock_ptr(pmd_ptdesc(pmd)); 3019} 3020 3021static inline bool pmd_ptlock_init(struct ptdesc *ptdesc) 3022{ 3023#ifdef CONFIG_TRANSPARENT_HUGEPAGE 3024 ptdesc->pmd_huge_pte = NULL; 3025#endif 3026 return ptlock_init(ptdesc); 3027} 3028 3029static inline void pmd_ptlock_free(struct ptdesc *ptdesc) 3030{ 3031#ifdef CONFIG_TRANSPARENT_HUGEPAGE 3032 VM_BUG_ON_PAGE(ptdesc->pmd_huge_pte, ptdesc_page(ptdesc)); 3033#endif 3034 ptlock_free(ptdesc); 3035} 3036 3037#define pmd_huge_pte(mm, pmd) (pmd_ptdesc(pmd)->pmd_huge_pte) 3038 3039#else 3040 3041static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) 3042{ 3043 return &mm->page_table_lock; 3044} 3045 3046static inline bool pmd_ptlock_init(struct ptdesc *ptdesc) { return true; } 3047static inline void pmd_ptlock_free(struct ptdesc *ptdesc) {} 3048 3049#define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte) 3050 3051#endif 3052 3053static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd) 3054{ 3055 spinlock_t *ptl = pmd_lockptr(mm, pmd); 3056 spin_lock(ptl); 3057 return ptl; 3058} 3059 3060static inline bool pagetable_pmd_ctor(struct ptdesc *ptdesc) 3061{ 3062 struct folio *folio = ptdesc_folio(ptdesc); 3063 3064 if (!pmd_ptlock_init(ptdesc)) 3065 return false; 3066 __folio_set_pgtable(folio); 3067 lruvec_stat_add_folio(folio, NR_PAGETABLE); 3068 return true; 3069} 3070 3071static inline void pagetable_pmd_dtor(struct ptdesc *ptdesc) 3072{ 3073 struct folio *folio = ptdesc_folio(ptdesc); 3074 3075 pmd_ptlock_free(ptdesc); 3076 __folio_clear_pgtable(folio); 3077 lruvec_stat_sub_folio(folio, NR_PAGETABLE); 3078} 3079 3080/* 3081 * No scalability reason to split PUD locks yet, but follow the same pattern 3082 * as the PMD locks to make it easier if we decide to. The VM should not be 3083 * considered ready to switch to split PUD locks yet; there may be places 3084 * which need to be converted from page_table_lock. 3085 */ 3086static inline spinlock_t *pud_lockptr(struct mm_struct *mm, pud_t *pud) 3087{ 3088 return &mm->page_table_lock; 3089} 3090 3091static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud) 3092{ 3093 spinlock_t *ptl = pud_lockptr(mm, pud); 3094 3095 spin_lock(ptl); 3096 return ptl; 3097} 3098 3099static inline void pagetable_pud_ctor(struct ptdesc *ptdesc) 3100{ 3101 struct folio *folio = ptdesc_folio(ptdesc); 3102 3103 __folio_set_pgtable(folio); 3104 lruvec_stat_add_folio(folio, NR_PAGETABLE); 3105} 3106 3107static inline void pagetable_pud_dtor(struct ptdesc *ptdesc) 3108{ 3109 struct folio *folio = ptdesc_folio(ptdesc); 3110 3111 __folio_clear_pgtable(folio); 3112 lruvec_stat_sub_folio(folio, NR_PAGETABLE); 3113} 3114 3115extern void __init pagecache_init(void); 3116extern void free_initmem(void); 3117 3118/* 3119 * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK) 3120 * into the buddy system. The freed pages will be poisoned with pattern 3121 * "poison" if it's within range [0, UCHAR_MAX]. 3122 * Return pages freed into the buddy system. 3123 */ 3124extern unsigned long free_reserved_area(void *start, void *end, 3125 int poison, const char *s); 3126 3127extern void adjust_managed_page_count(struct page *page, long count); 3128 3129extern void reserve_bootmem_region(phys_addr_t start, 3130 phys_addr_t end, int nid); 3131 3132/* Free the reserved page into the buddy system, so it gets managed. */ 3133static inline void free_reserved_page(struct page *page) 3134{ 3135 ClearPageReserved(page); 3136 init_page_count(page); 3137 __free_page(page); 3138 adjust_managed_page_count(page, 1); 3139} 3140#define free_highmem_page(page) free_reserved_page(page) 3141 3142static inline void mark_page_reserved(struct page *page) 3143{ 3144 SetPageReserved(page); 3145 adjust_managed_page_count(page, -1); 3146} 3147 3148static inline void free_reserved_ptdesc(struct ptdesc *pt) 3149{ 3150 free_reserved_page(ptdesc_page(pt)); 3151} 3152 3153/* 3154 * Default method to free all the __init memory into the buddy system. 3155 * The freed pages will be poisoned with pattern "poison" if it's within 3156 * range [0, UCHAR_MAX]. 3157 * Return pages freed into the buddy system. 3158 */ 3159static inline unsigned long free_initmem_default(int poison) 3160{ 3161 extern char __init_begin[], __init_end[]; 3162 3163 return free_reserved_area(&__init_begin, &__init_end, 3164 poison, "unused kernel image (initmem)"); 3165} 3166 3167static inline unsigned long get_num_physpages(void) 3168{ 3169 int nid; 3170 unsigned long phys_pages = 0; 3171 3172 for_each_online_node(nid) 3173 phys_pages += node_present_pages(nid); 3174 3175 return phys_pages; 3176} 3177 3178/* 3179 * Using memblock node mappings, an architecture may initialise its 3180 * zones, allocate the backing mem_map and account for memory holes in an 3181 * architecture independent manner. 3182 * 3183 * An architecture is expected to register range of page frames backed by 3184 * physical memory with memblock_add[_node]() before calling 3185 * free_area_init() passing in the PFN each zone ends at. At a basic 3186 * usage, an architecture is expected to do something like 3187 * 3188 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn, 3189 * max_highmem_pfn}; 3190 * for_each_valid_physical_page_range() 3191 * memblock_add_node(base, size, nid, MEMBLOCK_NONE) 3192 * free_area_init(max_zone_pfns); 3193 */ 3194void free_area_init(unsigned long *max_zone_pfn); 3195unsigned long node_map_pfn_alignment(void); 3196unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn, 3197 unsigned long end_pfn); 3198extern unsigned long absent_pages_in_range(unsigned long start_pfn, 3199 unsigned long end_pfn); 3200extern void get_pfn_range_for_nid(unsigned int nid, 3201 unsigned long *start_pfn, unsigned long *end_pfn); 3202 3203#ifndef CONFIG_NUMA 3204static inline int early_pfn_to_nid(unsigned long pfn) 3205{ 3206 return 0; 3207} 3208#else 3209/* please see mm/page_alloc.c */ 3210extern int __meminit early_pfn_to_nid(unsigned long pfn); 3211#endif 3212 3213extern void set_dma_reserve(unsigned long new_dma_reserve); 3214extern void mem_init(void); 3215extern void __init mmap_init(void); 3216 3217extern void __show_mem(unsigned int flags, nodemask_t *nodemask, int max_zone_idx); 3218static inline void show_mem(void) 3219{ 3220 __show_mem(0, NULL, MAX_NR_ZONES - 1); 3221} 3222extern long si_mem_available(void); 3223extern void si_meminfo(struct sysinfo * val); 3224extern void si_meminfo_node(struct sysinfo *val, int nid); 3225#ifdef __HAVE_ARCH_RESERVED_KERNEL_PAGES 3226extern unsigned long arch_reserved_kernel_pages(void); 3227#endif 3228 3229extern __printf(3, 4) 3230void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...); 3231 3232extern void setup_per_cpu_pageset(void); 3233 3234/* nommu.c */ 3235extern atomic_long_t mmap_pages_allocated; 3236extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t); 3237 3238/* interval_tree.c */ 3239void vma_interval_tree_insert(struct vm_area_struct *node, 3240 struct rb_root_cached *root); 3241void vma_interval_tree_insert_after(struct vm_area_struct *node, 3242 struct vm_area_struct *prev, 3243 struct rb_root_cached *root); 3244void vma_interval_tree_remove(struct vm_area_struct *node, 3245 struct rb_root_cached *root); 3246struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root_cached *root, 3247 unsigned long start, unsigned long last); 3248struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node, 3249 unsigned long start, unsigned long last); 3250 3251#define vma_interval_tree_foreach(vma, root, start, last) \ 3252 for (vma = vma_interval_tree_iter_first(root, start, last); \ 3253 vma; vma = vma_interval_tree_iter_next(vma, start, last)) 3254 3255void anon_vma_interval_tree_insert(struct anon_vma_chain *node, 3256 struct rb_root_cached *root); 3257void anon_vma_interval_tree_remove(struct anon_vma_chain *node, 3258 struct rb_root_cached *root); 3259struct anon_vma_chain * 3260anon_vma_interval_tree_iter_first(struct rb_root_cached *root, 3261 unsigned long start, unsigned long last); 3262struct anon_vma_chain *anon_vma_interval_tree_iter_next( 3263 struct anon_vma_chain *node, unsigned long start, unsigned long last); 3264#ifdef CONFIG_DEBUG_VM_RB 3265void anon_vma_interval_tree_verify(struct anon_vma_chain *node); 3266#endif 3267 3268#define anon_vma_interval_tree_foreach(avc, root, start, last) \ 3269 for (avc = anon_vma_interval_tree_iter_first(root, start, last); \ 3270 avc; avc = anon_vma_interval_tree_iter_next(avc, start, last)) 3271 3272/* mmap.c */ 3273extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin); 3274extern int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma, 3275 unsigned long start, unsigned long end, pgoff_t pgoff, 3276 struct vm_area_struct *next); 3277extern int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma, 3278 unsigned long start, unsigned long end, pgoff_t pgoff); 3279extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *); 3280extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *); 3281extern void unlink_file_vma(struct vm_area_struct *); 3282extern struct vm_area_struct *copy_vma(struct vm_area_struct **, 3283 unsigned long addr, unsigned long len, pgoff_t pgoff, 3284 bool *need_rmap_locks); 3285extern void exit_mmap(struct mm_struct *); 3286struct vm_area_struct *vma_modify(struct vma_iterator *vmi, 3287 struct vm_area_struct *prev, 3288 struct vm_area_struct *vma, 3289 unsigned long start, unsigned long end, 3290 unsigned long vm_flags, 3291 struct mempolicy *policy, 3292 struct vm_userfaultfd_ctx uffd_ctx, 3293 struct anon_vma_name *anon_name); 3294 3295/* We are about to modify the VMA's flags. */ 3296static inline struct vm_area_struct 3297*vma_modify_flags(struct vma_iterator *vmi, 3298 struct vm_area_struct *prev, 3299 struct vm_area_struct *vma, 3300 unsigned long start, unsigned long end, 3301 unsigned long new_flags) 3302{ 3303 return vma_modify(vmi, prev, vma, start, end, new_flags, 3304 vma_policy(vma), vma->vm_userfaultfd_ctx, 3305 anon_vma_name(vma)); 3306} 3307 3308/* We are about to modify the VMA's flags and/or anon_name. */ 3309static inline struct vm_area_struct 3310*vma_modify_flags_name(struct vma_iterator *vmi, 3311 struct vm_area_struct *prev, 3312 struct vm_area_struct *vma, 3313 unsigned long start, 3314 unsigned long end, 3315 unsigned long new_flags, 3316 struct anon_vma_name *new_name) 3317{ 3318 return vma_modify(vmi, prev, vma, start, end, new_flags, 3319 vma_policy(vma), vma->vm_userfaultfd_ctx, new_name); 3320} 3321 3322/* We are about to modify the VMA's memory policy. */ 3323static inline struct vm_area_struct 3324*vma_modify_policy(struct vma_iterator *vmi, 3325 struct vm_area_struct *prev, 3326 struct vm_area_struct *vma, 3327 unsigned long start, unsigned long end, 3328 struct mempolicy *new_pol) 3329{ 3330 return vma_modify(vmi, prev, vma, start, end, vma->vm_flags, 3331 new_pol, vma->vm_userfaultfd_ctx, anon_vma_name(vma)); 3332} 3333 3334/* We are about to modify the VMA's flags and/or uffd context. */ 3335static inline struct vm_area_struct 3336*vma_modify_flags_uffd(struct vma_iterator *vmi, 3337 struct vm_area_struct *prev, 3338 struct vm_area_struct *vma, 3339 unsigned long start, unsigned long end, 3340 unsigned long new_flags, 3341 struct vm_userfaultfd_ctx new_ctx) 3342{ 3343 return vma_modify(vmi, prev, vma, start, end, new_flags, 3344 vma_policy(vma), new_ctx, anon_vma_name(vma)); 3345} 3346 3347static inline int check_data_rlimit(unsigned long rlim, 3348 unsigned long new, 3349 unsigned long start, 3350 unsigned long end_data, 3351 unsigned long start_data) 3352{ 3353 if (rlim < RLIM_INFINITY) { 3354 if (((new - start) + (end_data - start_data)) > rlim) 3355 return -ENOSPC; 3356 } 3357 3358 return 0; 3359} 3360 3361extern int mm_take_all_locks(struct mm_struct *mm); 3362extern void mm_drop_all_locks(struct mm_struct *mm); 3363 3364extern int set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file); 3365extern int replace_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file); 3366extern struct file *get_mm_exe_file(struct mm_struct *mm); 3367extern struct file *get_task_exe_file(struct task_struct *task); 3368 3369extern bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long npages); 3370extern void vm_stat_account(struct mm_struct *, vm_flags_t, long npages); 3371 3372extern bool vma_is_special_mapping(const struct vm_area_struct *vma, 3373 const struct vm_special_mapping *sm); 3374extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm, 3375 unsigned long addr, unsigned long len, 3376 unsigned long flags, 3377 const struct vm_special_mapping *spec); 3378/* This is an obsolete alternative to _install_special_mapping. */ 3379extern int install_special_mapping(struct mm_struct *mm, 3380 unsigned long addr, unsigned long len, 3381 unsigned long flags, struct page **pages); 3382 3383unsigned long randomize_stack_top(unsigned long stack_top); 3384unsigned long randomize_page(unsigned long start, unsigned long range); 3385 3386extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); 3387 3388extern unsigned long mmap_region(struct file *file, unsigned long addr, 3389 unsigned long len, vm_flags_t vm_flags, unsigned long pgoff, 3390 struct list_head *uf); 3391extern unsigned long do_mmap(struct file *file, unsigned long addr, 3392 unsigned long len, unsigned long prot, unsigned long flags, 3393 vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate, 3394 struct list_head *uf); 3395extern int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm, 3396 unsigned long start, size_t len, struct list_head *uf, 3397 bool unlock); 3398extern int do_munmap(struct mm_struct *, unsigned long, size_t, 3399 struct list_head *uf); 3400extern int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior); 3401 3402#ifdef CONFIG_MMU 3403extern int do_vma_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma, 3404 unsigned long start, unsigned long end, 3405 struct list_head *uf, bool unlock); 3406extern int __mm_populate(unsigned long addr, unsigned long len, 3407 int ignore_errors); 3408static inline void mm_populate(unsigned long addr, unsigned long len) 3409{ 3410 /* Ignore errors */ 3411 (void) __mm_populate(addr, len, 1); 3412} 3413#else 3414static inline void mm_populate(unsigned long addr, unsigned long len) {} 3415#endif 3416 3417/* This takes the mm semaphore itself */ 3418extern int __must_check vm_brk_flags(unsigned long, unsigned long, unsigned long); 3419extern int vm_munmap(unsigned long, size_t); 3420extern unsigned long __must_check vm_mmap(struct file *, unsigned long, 3421 unsigned long, unsigned long, 3422 unsigned long, unsigned long); 3423 3424struct vm_unmapped_area_info { 3425#define VM_UNMAPPED_AREA_TOPDOWN 1 3426 unsigned long flags; 3427 unsigned long length; 3428 unsigned long low_limit; 3429 unsigned long high_limit; 3430 unsigned long align_mask; 3431 unsigned long align_offset; 3432}; 3433 3434extern unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info); 3435 3436/* truncate.c */ 3437extern void truncate_inode_pages(struct address_space *, loff_t); 3438extern void truncate_inode_pages_range(struct address_space *, 3439 loff_t lstart, loff_t lend); 3440extern void truncate_inode_pages_final(struct address_space *); 3441 3442/* generic vm_area_ops exported for stackable file systems */ 3443extern vm_fault_t filemap_fault(struct vm_fault *vmf); 3444extern vm_fault_t filemap_map_pages(struct vm_fault *vmf, 3445 pgoff_t start_pgoff, pgoff_t end_pgoff); 3446extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf); 3447 3448extern unsigned long stack_guard_gap; 3449/* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */ 3450int expand_stack_locked(struct vm_area_struct *vma, unsigned long address); 3451struct vm_area_struct *expand_stack(struct mm_struct * mm, unsigned long addr); 3452 3453/* CONFIG_STACK_GROWSUP still needs to grow downwards at some places */ 3454int expand_downwards(struct vm_area_struct *vma, unsigned long address); 3455 3456/* Look up the first VMA which satisfies addr < vm_end, NULL if none. */ 3457extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr); 3458extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr, 3459 struct vm_area_struct **pprev); 3460 3461/* 3462 * Look up the first VMA which intersects the interval [start_addr, end_addr) 3463 * NULL if none. Assume start_addr < end_addr. 3464 */ 3465struct vm_area_struct *find_vma_intersection(struct mm_struct *mm, 3466 unsigned long start_addr, unsigned long end_addr); 3467 3468/** 3469 * vma_lookup() - Find a VMA at a specific address 3470 * @mm: The process address space. 3471 * @addr: The user address. 3472 * 3473 * Return: The vm_area_struct at the given address, %NULL otherwise. 3474 */ 3475static inline 3476struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr) 3477{ 3478 return mtree_load(&mm->mm_mt, addr); 3479} 3480 3481static inline unsigned long stack_guard_start_gap(struct vm_area_struct *vma) 3482{ 3483 if (vma->vm_flags & VM_GROWSDOWN) 3484 return stack_guard_gap; 3485 3486 /* See reasoning around the VM_SHADOW_STACK definition */ 3487 if (vma->vm_flags & VM_SHADOW_STACK) 3488 return PAGE_SIZE; 3489 3490 return 0; 3491} 3492 3493static inline unsigned long vm_start_gap(struct vm_area_struct *vma) 3494{ 3495 unsigned long gap = stack_guard_start_gap(vma); 3496 unsigned long vm_start = vma->vm_start; 3497 3498 vm_start -= gap; 3499 if (vm_start > vma->vm_start) 3500 vm_start = 0; 3501 return vm_start; 3502} 3503 3504static inline unsigned long vm_end_gap(struct vm_area_struct *vma) 3505{ 3506 unsigned long vm_end = vma->vm_end; 3507 3508 if (vma->vm_flags & VM_GROWSUP) { 3509 vm_end += stack_guard_gap; 3510 if (vm_end < vma->vm_end) 3511 vm_end = -PAGE_SIZE; 3512 } 3513 return vm_end; 3514} 3515 3516static inline unsigned long vma_pages(struct vm_area_struct *vma) 3517{ 3518 return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; 3519} 3520 3521/* Look up the first VMA which exactly match the interval vm_start ... vm_end */ 3522static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm, 3523 unsigned long vm_start, unsigned long vm_end) 3524{ 3525 struct vm_area_struct *vma = vma_lookup(mm, vm_start); 3526 3527 if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end)) 3528 vma = NULL; 3529 3530 return vma; 3531} 3532 3533static inline bool range_in_vma(struct vm_area_struct *vma, 3534 unsigned long start, unsigned long end) 3535{ 3536 return (vma && vma->vm_start <= start && end <= vma->vm_end); 3537} 3538 3539#ifdef CONFIG_MMU 3540pgprot_t vm_get_page_prot(unsigned long vm_flags); 3541void vma_set_page_prot(struct vm_area_struct *vma); 3542#else 3543static inline pgprot_t vm_get_page_prot(unsigned long vm_flags) 3544{ 3545 return __pgprot(0); 3546} 3547static inline void vma_set_page_prot(struct vm_area_struct *vma) 3548{ 3549 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); 3550} 3551#endif 3552 3553void vma_set_file(struct vm_area_struct *vma, struct file *file); 3554 3555#ifdef CONFIG_NUMA_BALANCING 3556unsigned long change_prot_numa(struct vm_area_struct *vma, 3557 unsigned long start, unsigned long end); 3558#endif 3559 3560struct vm_area_struct *find_extend_vma_locked(struct mm_struct *, 3561 unsigned long addr); 3562int remap_pfn_range(struct vm_area_struct *, unsigned long addr, 3563 unsigned long pfn, unsigned long size, pgprot_t); 3564int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr, 3565 unsigned long pfn, unsigned long size, pgprot_t prot); 3566int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *); 3567int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr, 3568 struct page **pages, unsigned long *num); 3569int vm_map_pages(struct vm_area_struct *vma, struct page **pages, 3570 unsigned long num); 3571int vm_map_pages_zero(struct vm_area_struct *vma, struct page **pages, 3572 unsigned long num); 3573vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr, 3574 unsigned long pfn); 3575vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr, 3576 unsigned long pfn, pgprot_t pgprot); 3577vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr, 3578 pfn_t pfn); 3579vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma, 3580 unsigned long addr, pfn_t pfn); 3581int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len); 3582 3583static inline vm_fault_t vmf_insert_page(struct vm_area_struct *vma, 3584 unsigned long addr, struct page *page) 3585{ 3586 int err = vm_insert_page(vma, addr, page); 3587 3588 if (err == -ENOMEM) 3589 return VM_FAULT_OOM; 3590 if (err < 0 && err != -EBUSY) 3591 return VM_FAULT_SIGBUS; 3592 3593 return VM_FAULT_NOPAGE; 3594} 3595 3596#ifndef io_remap_pfn_range 3597static inline int io_remap_pfn_range(struct vm_area_struct *vma, 3598 unsigned long addr, unsigned long pfn, 3599 unsigned long size, pgprot_t prot) 3600{ 3601 return remap_pfn_range(vma, addr, pfn, size, pgprot_decrypted(prot)); 3602} 3603#endif 3604 3605static inline vm_fault_t vmf_error(int err) 3606{ 3607 if (err == -ENOMEM) 3608 return VM_FAULT_OOM; 3609 else if (err == -EHWPOISON) 3610 return VM_FAULT_HWPOISON; 3611 return VM_FAULT_SIGBUS; 3612} 3613 3614/* 3615 * Convert errno to return value for ->page_mkwrite() calls. 3616 * 3617 * This should eventually be merged with vmf_error() above, but will need a 3618 * careful audit of all vmf_error() callers. 3619 */ 3620static inline vm_fault_t vmf_fs_error(int err) 3621{ 3622 if (err == 0) 3623 return VM_FAULT_LOCKED; 3624 if (err == -EFAULT || err == -EAGAIN) 3625 return VM_FAULT_NOPAGE; 3626 if (err == -ENOMEM) 3627 return VM_FAULT_OOM; 3628 /* -ENOSPC, -EDQUOT, -EIO ... */ 3629 return VM_FAULT_SIGBUS; 3630} 3631 3632struct page *follow_page(struct vm_area_struct *vma, unsigned long address, 3633 unsigned int foll_flags); 3634 3635static inline int vm_fault_to_errno(vm_fault_t vm_fault, int foll_flags) 3636{ 3637 if (vm_fault & VM_FAULT_OOM) 3638 return -ENOMEM; 3639 if (vm_fault & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE)) 3640 return (foll_flags & FOLL_HWPOISON) ? -EHWPOISON : -EFAULT; 3641 if (vm_fault & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV)) 3642 return -EFAULT; 3643 return 0; 3644} 3645 3646/* 3647 * Indicates whether GUP can follow a PROT_NONE mapped page, or whether 3648 * a (NUMA hinting) fault is required. 3649 */ 3650static inline bool gup_can_follow_protnone(struct vm_area_struct *vma, 3651 unsigned int flags) 3652{ 3653 /* 3654 * If callers don't want to honor NUMA hinting faults, no need to 3655 * determine if we would actually have to trigger a NUMA hinting fault. 3656 */ 3657 if (!(flags & FOLL_HONOR_NUMA_FAULT)) 3658 return true; 3659 3660 /* 3661 * NUMA hinting faults don't apply in inaccessible (PROT_NONE) VMAs. 3662 * 3663 * Requiring a fault here even for inaccessible VMAs would mean that 3664 * FOLL_FORCE cannot make any progress, because handle_mm_fault() 3665 * refuses to process NUMA hinting faults in inaccessible VMAs. 3666 */ 3667 return !vma_is_accessible(vma); 3668} 3669 3670typedef int (*pte_fn_t)(pte_t *pte, unsigned long addr, void *data); 3671extern int apply_to_page_range(struct mm_struct *mm, unsigned long address, 3672 unsigned long size, pte_fn_t fn, void *data); 3673extern int apply_to_existing_page_range(struct mm_struct *mm, 3674 unsigned long address, unsigned long size, 3675 pte_fn_t fn, void *data); 3676 3677#ifdef CONFIG_PAGE_POISONING 3678extern void __kernel_poison_pages(struct page *page, int numpages); 3679extern void __kernel_unpoison_pages(struct page *page, int numpages); 3680extern bool _page_poisoning_enabled_early; 3681DECLARE_STATIC_KEY_FALSE(_page_poisoning_enabled); 3682static inline bool page_poisoning_enabled(void) 3683{ 3684 return _page_poisoning_enabled_early; 3685} 3686/* 3687 * For use in fast paths after init_mem_debugging() has run, or when a 3688 * false negative result is not harmful when called too early. 3689 */ 3690static inline bool page_poisoning_enabled_static(void) 3691{ 3692 return static_branch_unlikely(&_page_poisoning_enabled); 3693} 3694static inline void kernel_poison_pages(struct page *page, int numpages) 3695{ 3696 if (page_poisoning_enabled_static()) 3697 __kernel_poison_pages(page, numpages); 3698} 3699static inline void kernel_unpoison_pages(struct page *page, int numpages) 3700{ 3701 if (page_poisoning_enabled_static()) 3702 __kernel_unpoison_pages(page, numpages); 3703} 3704#else 3705static inline bool page_poisoning_enabled(void) { return false; } 3706static inline bool page_poisoning_enabled_static(void) { return false; } 3707static inline void __kernel_poison_pages(struct page *page, int nunmpages) { } 3708static inline void kernel_poison_pages(struct page *page, int numpages) { } 3709static inline void kernel_unpoison_pages(struct page *page, int numpages) { } 3710#endif 3711 3712DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc); 3713static inline bool want_init_on_alloc(gfp_t flags) 3714{ 3715 if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, 3716 &init_on_alloc)) 3717 return true; 3718 return flags & __GFP_ZERO; 3719} 3720 3721DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free); 3722static inline bool want_init_on_free(void) 3723{ 3724 return static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON, 3725 &init_on_free); 3726} 3727 3728extern bool _debug_pagealloc_enabled_early; 3729DECLARE_STATIC_KEY_FALSE(_debug_pagealloc_enabled); 3730 3731static inline bool debug_pagealloc_enabled(void) 3732{ 3733 return IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) && 3734 _debug_pagealloc_enabled_early; 3735} 3736 3737/* 3738 * For use in fast paths after mem_debugging_and_hardening_init() has run, 3739 * or when a false negative result is not harmful when called too early. 3740 */ 3741static inline bool debug_pagealloc_enabled_static(void) 3742{ 3743 if (!IS_ENABLED(CONFIG_DEBUG_PAGEALLOC)) 3744 return false; 3745 3746 return static_branch_unlikely(&_debug_pagealloc_enabled); 3747} 3748 3749/* 3750 * To support DEBUG_PAGEALLOC architecture must ensure that 3751 * __kernel_map_pages() never fails 3752 */ 3753extern void __kernel_map_pages(struct page *page, int numpages, int enable); 3754#ifdef CONFIG_DEBUG_PAGEALLOC 3755static inline void debug_pagealloc_map_pages(struct page *page, int numpages) 3756{ 3757 if (debug_pagealloc_enabled_static()) 3758 __kernel_map_pages(page, numpages, 1); 3759} 3760 3761static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) 3762{ 3763 if (debug_pagealloc_enabled_static()) 3764 __kernel_map_pages(page, numpages, 0); 3765} 3766 3767extern unsigned int _debug_guardpage_minorder; 3768DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled); 3769 3770static inline unsigned int debug_guardpage_minorder(void) 3771{ 3772 return _debug_guardpage_minorder; 3773} 3774 3775static inline bool debug_guardpage_enabled(void) 3776{ 3777 return static_branch_unlikely(&_debug_guardpage_enabled); 3778} 3779 3780static inline bool page_is_guard(struct page *page) 3781{ 3782 if (!debug_guardpage_enabled()) 3783 return false; 3784 3785 return PageGuard(page); 3786} 3787 3788bool __set_page_guard(struct zone *zone, struct page *page, unsigned int order, 3789 int migratetype); 3790static inline bool set_page_guard(struct zone *zone, struct page *page, 3791 unsigned int order, int migratetype) 3792{ 3793 if (!debug_guardpage_enabled()) 3794 return false; 3795 return __set_page_guard(zone, page, order, migratetype); 3796} 3797 3798void __clear_page_guard(struct zone *zone, struct page *page, unsigned int order, 3799 int migratetype); 3800static inline void clear_page_guard(struct zone *zone, struct page *page, 3801 unsigned int order, int migratetype) 3802{ 3803 if (!debug_guardpage_enabled()) 3804 return; 3805 __clear_page_guard(zone, page, order, migratetype); 3806} 3807 3808#else /* CONFIG_DEBUG_PAGEALLOC */ 3809static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {} 3810static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {} 3811static inline unsigned int debug_guardpage_minorder(void) { return 0; } 3812static inline bool debug_guardpage_enabled(void) { return false; } 3813static inline bool page_is_guard(struct page *page) { return false; } 3814static inline bool set_page_guard(struct zone *zone, struct page *page, 3815 unsigned int order, int migratetype) { return false; } 3816static inline void clear_page_guard(struct zone *zone, struct page *page, 3817 unsigned int order, int migratetype) {} 3818#endif /* CONFIG_DEBUG_PAGEALLOC */ 3819 3820#ifdef __HAVE_ARCH_GATE_AREA 3821extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm); 3822extern int in_gate_area_no_mm(unsigned long addr); 3823extern int in_gate_area(struct mm_struct *mm, unsigned long addr); 3824#else 3825static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm) 3826{ 3827 return NULL; 3828} 3829static inline int in_gate_area_no_mm(unsigned long addr) { return 0; } 3830static inline int in_gate_area(struct mm_struct *mm, unsigned long addr) 3831{ 3832 return 0; 3833} 3834#endif /* __HAVE_ARCH_GATE_AREA */ 3835 3836extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm); 3837 3838#ifdef CONFIG_SYSCTL 3839extern int sysctl_drop_caches; 3840int drop_caches_sysctl_handler(struct ctl_table *, int, void *, size_t *, 3841 loff_t *); 3842#endif 3843 3844void drop_slab(void); 3845 3846#ifndef CONFIG_MMU 3847#define randomize_va_space 0 3848#else 3849extern int randomize_va_space; 3850#endif 3851 3852const char * arch_vma_name(struct vm_area_struct *vma); 3853#ifdef CONFIG_MMU 3854void print_vma_addr(char *prefix, unsigned long rip); 3855#else 3856static inline void print_vma_addr(char *prefix, unsigned long rip) 3857{ 3858} 3859#endif 3860 3861void *sparse_buffer_alloc(unsigned long size); 3862struct page * __populate_section_memmap(unsigned long pfn, 3863 unsigned long nr_pages, int nid, struct vmem_altmap *altmap, 3864 struct dev_pagemap *pgmap); 3865void pmd_init(void *addr); 3866void pud_init(void *addr); 3867pgd_t *vmemmap_pgd_populate(unsigned long addr, int node); 3868p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node); 3869pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node); 3870pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node); 3871pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node, 3872 struct vmem_altmap *altmap, struct page *reuse); 3873void *vmemmap_alloc_block(unsigned long size, int node); 3874struct vmem_altmap; 3875void *vmemmap_alloc_block_buf(unsigned long size, int node, 3876 struct vmem_altmap *altmap); 3877void vmemmap_verify(pte_t *, int, unsigned long, unsigned long); 3878void vmemmap_set_pmd(pmd_t *pmd, void *p, int node, 3879 unsigned long addr, unsigned long next); 3880int vmemmap_check_pmd(pmd_t *pmd, int node, 3881 unsigned long addr, unsigned long next); 3882int vmemmap_populate_basepages(unsigned long start, unsigned long end, 3883 int node, struct vmem_altmap *altmap); 3884int vmemmap_populate_hugepages(unsigned long start, unsigned long end, 3885 int node, struct vmem_altmap *altmap); 3886int vmemmap_populate(unsigned long start, unsigned long end, int node, 3887 struct vmem_altmap *altmap); 3888void vmemmap_populate_print_last(void); 3889#ifdef CONFIG_MEMORY_HOTPLUG 3890void vmemmap_free(unsigned long start, unsigned long end, 3891 struct vmem_altmap *altmap); 3892#endif 3893 3894#ifdef CONFIG_SPARSEMEM_VMEMMAP 3895static inline unsigned long vmem_altmap_offset(struct vmem_altmap *altmap) 3896{ 3897 /* number of pfns from base where pfn_to_page() is valid */ 3898 if (altmap) 3899 return altmap->reserve + altmap->free; 3900 return 0; 3901} 3902 3903static inline void vmem_altmap_free(struct vmem_altmap *altmap, 3904 unsigned long nr_pfns) 3905{ 3906 altmap->alloc -= nr_pfns; 3907} 3908#else 3909static inline unsigned long vmem_altmap_offset(struct vmem_altmap *altmap) 3910{ 3911 return 0; 3912} 3913 3914static inline void vmem_altmap_free(struct vmem_altmap *altmap, 3915 unsigned long nr_pfns) 3916{ 3917} 3918#endif 3919 3920#define VMEMMAP_RESERVE_NR 2 3921#ifdef CONFIG_ARCH_WANT_OPTIMIZE_DAX_VMEMMAP 3922static inline bool __vmemmap_can_optimize(struct vmem_altmap *altmap, 3923 struct dev_pagemap *pgmap) 3924{ 3925 unsigned long nr_pages; 3926 unsigned long nr_vmemmap_pages; 3927 3928 if (!pgmap || !is_power_of_2(sizeof(struct page))) 3929 return false; 3930 3931 nr_pages = pgmap_vmemmap_nr(pgmap); 3932 nr_vmemmap_pages = ((nr_pages * sizeof(struct page)) >> PAGE_SHIFT); 3933 /* 3934 * For vmemmap optimization with DAX we need minimum 2 vmemmap 3935 * pages. See layout diagram in Documentation/mm/vmemmap_dedup.rst 3936 */ 3937 return !altmap && (nr_vmemmap_pages > VMEMMAP_RESERVE_NR); 3938} 3939/* 3940 * If we don't have an architecture override, use the generic rule 3941 */ 3942#ifndef vmemmap_can_optimize 3943#define vmemmap_can_optimize __vmemmap_can_optimize 3944#endif 3945 3946#else 3947static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap, 3948 struct dev_pagemap *pgmap) 3949{ 3950 return false; 3951} 3952#endif 3953 3954void register_page_bootmem_memmap(unsigned long section_nr, struct page *map, 3955 unsigned long nr_pages); 3956 3957enum mf_flags { 3958 MF_COUNT_INCREASED = 1 << 0, 3959 MF_ACTION_REQUIRED = 1 << 1, 3960 MF_MUST_KILL = 1 << 2, 3961 MF_SOFT_OFFLINE = 1 << 3, 3962 MF_UNPOISON = 1 << 4, 3963 MF_SW_SIMULATED = 1 << 5, 3964 MF_NO_RETRY = 1 << 6, 3965 MF_MEM_PRE_REMOVE = 1 << 7, 3966}; 3967int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, 3968 unsigned long count, int mf_flags); 3969extern int memory_failure(unsigned long pfn, int flags); 3970extern void memory_failure_queue_kick(int cpu); 3971extern int unpoison_memory(unsigned long pfn); 3972extern void shake_page(struct page *p); 3973extern atomic_long_t num_poisoned_pages __read_mostly; 3974extern int soft_offline_page(unsigned long pfn, int flags); 3975#ifdef CONFIG_MEMORY_FAILURE 3976/* 3977 * Sysfs entries for memory failure handling statistics. 3978 */ 3979extern const struct attribute_group memory_failure_attr_group; 3980extern void memory_failure_queue(unsigned long pfn, int flags); 3981extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, 3982 bool *migratable_cleared); 3983void num_poisoned_pages_inc(unsigned long pfn); 3984void num_poisoned_pages_sub(unsigned long pfn, long i); 3985struct task_struct *task_early_kill(struct task_struct *tsk, int force_early); 3986#else 3987static inline void memory_failure_queue(unsigned long pfn, int flags) 3988{ 3989} 3990 3991static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, 3992 bool *migratable_cleared) 3993{ 3994 return 0; 3995} 3996 3997static inline void num_poisoned_pages_inc(unsigned long pfn) 3998{ 3999} 4000 4001static inline void num_poisoned_pages_sub(unsigned long pfn, long i) 4002{ 4003} 4004#endif 4005 4006#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_KSM) 4007void add_to_kill_ksm(struct task_struct *tsk, struct page *p, 4008 struct vm_area_struct *vma, struct list_head *to_kill, 4009 unsigned long ksm_addr); 4010#endif 4011 4012#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) 4013extern void memblk_nr_poison_inc(unsigned long pfn); 4014extern void memblk_nr_poison_sub(unsigned long pfn, long i); 4015#else 4016static inline void memblk_nr_poison_inc(unsigned long pfn) 4017{ 4018} 4019 4020static inline void memblk_nr_poison_sub(unsigned long pfn, long i) 4021{ 4022} 4023#endif 4024 4025#ifndef arch_memory_failure 4026static inline int arch_memory_failure(unsigned long pfn, int flags) 4027{ 4028 return -ENXIO; 4029} 4030#endif 4031 4032#ifndef arch_is_platform_page 4033static inline bool arch_is_platform_page(u64 paddr) 4034{ 4035 return false; 4036} 4037#endif 4038 4039/* 4040 * Error handlers for various types of pages. 4041 */ 4042enum mf_result { 4043 MF_IGNORED, /* Error: cannot be handled */ 4044 MF_FAILED, /* Error: handling failed */ 4045 MF_DELAYED, /* Will be handled later */ 4046 MF_RECOVERED, /* Successfully recovered */ 4047}; 4048 4049enum mf_action_page_type { 4050 MF_MSG_KERNEL, 4051 MF_MSG_KERNEL_HIGH_ORDER, 4052 MF_MSG_SLAB, 4053 MF_MSG_DIFFERENT_COMPOUND, 4054 MF_MSG_HUGE, 4055 MF_MSG_FREE_HUGE, 4056 MF_MSG_UNMAP_FAILED, 4057 MF_MSG_DIRTY_SWAPCACHE, 4058 MF_MSG_CLEAN_SWAPCACHE, 4059 MF_MSG_DIRTY_MLOCKED_LRU, 4060 MF_MSG_CLEAN_MLOCKED_LRU, 4061 MF_MSG_DIRTY_UNEVICTABLE_LRU, 4062 MF_MSG_CLEAN_UNEVICTABLE_LRU, 4063 MF_MSG_DIRTY_LRU, 4064 MF_MSG_CLEAN_LRU, 4065 MF_MSG_TRUNCATED_LRU, 4066 MF_MSG_BUDDY, 4067 MF_MSG_DAX, 4068 MF_MSG_UNSPLIT_THP, 4069 MF_MSG_UNKNOWN, 4070}; 4071 4072#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS) 4073extern void clear_huge_page(struct page *page, 4074 unsigned long addr_hint, 4075 unsigned int pages_per_huge_page); 4076int copy_user_large_folio(struct folio *dst, struct folio *src, 4077 unsigned long addr_hint, 4078 struct vm_area_struct *vma); 4079long copy_folio_from_user(struct folio *dst_folio, 4080 const void __user *usr_src, 4081 bool allow_pagefault); 4082 4083/** 4084 * vma_is_special_huge - Are transhuge page-table entries considered special? 4085 * @vma: Pointer to the struct vm_area_struct to consider 4086 * 4087 * Whether transhuge page-table entries are considered "special" following 4088 * the definition in vm_normal_page(). 4089 * 4090 * Return: true if transhuge page-table entries should be considered special, 4091 * false otherwise. 4092 */ 4093static inline bool vma_is_special_huge(const struct vm_area_struct *vma) 4094{ 4095 return vma_is_dax(vma) || (vma->vm_file && 4096 (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP))); 4097} 4098 4099#endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */ 4100 4101#if MAX_NUMNODES > 1 4102void __init setup_nr_node_ids(void); 4103#else 4104static inline void setup_nr_node_ids(void) {} 4105#endif 4106 4107extern int memcmp_pages(struct page *page1, struct page *page2); 4108 4109static inline int pages_identical(struct page *page1, struct page *page2) 4110{ 4111 return !memcmp_pages(page1, page2); 4112} 4113 4114#ifdef CONFIG_MAPPING_DIRTY_HELPERS 4115unsigned long clean_record_shared_mapping_range(struct address_space *mapping, 4116 pgoff_t first_index, pgoff_t nr, 4117 pgoff_t bitmap_pgoff, 4118 unsigned long *bitmap, 4119 pgoff_t *start, 4120 pgoff_t *end); 4121 4122unsigned long wp_shared_mapping_range(struct address_space *mapping, 4123 pgoff_t first_index, pgoff_t nr); 4124#endif 4125 4126extern int sysctl_nr_trim_pages; 4127 4128#ifdef CONFIG_PRINTK 4129void mem_dump_obj(void *object); 4130#else 4131static inline void mem_dump_obj(void *object) {} 4132#endif 4133 4134/** 4135 * seal_check_write - Check for F_SEAL_WRITE or F_SEAL_FUTURE_WRITE flags and 4136 * handle them. 4137 * @seals: the seals to check 4138 * @vma: the vma to operate on 4139 * 4140 * Check whether F_SEAL_WRITE or F_SEAL_FUTURE_WRITE are set; if so, do proper 4141 * check/handling on the vma flags. Return 0 if check pass, or <0 for errors. 4142 */ 4143static inline int seal_check_write(int seals, struct vm_area_struct *vma) 4144{ 4145 if (seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) { 4146 /* 4147 * New PROT_WRITE and MAP_SHARED mmaps are not allowed when 4148 * write seals are active. 4149 */ 4150 if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE)) 4151 return -EPERM; 4152 4153 /* 4154 * Since an F_SEAL_[FUTURE_]WRITE sealed memfd can be mapped as 4155 * MAP_SHARED and read-only, take care to not allow mprotect to 4156 * revert protections on such mappings. Do this only for shared 4157 * mappings. For private mappings, don't need to mask 4158 * VM_MAYWRITE as we still want them to be COW-writable. 4159 */ 4160 if (vma->vm_flags & VM_SHARED) 4161 vm_flags_clear(vma, VM_MAYWRITE); 4162 } 4163 4164 return 0; 4165} 4166 4167#ifdef CONFIG_ANON_VMA_NAME 4168int madvise_set_anon_name(struct mm_struct *mm, unsigned long start, 4169 unsigned long len_in, 4170 struct anon_vma_name *anon_name); 4171#else 4172static inline int 4173madvise_set_anon_name(struct mm_struct *mm, unsigned long start, 4174 unsigned long len_in, struct anon_vma_name *anon_name) { 4175 return 0; 4176} 4177#endif 4178 4179#ifdef CONFIG_UNACCEPTED_MEMORY 4180 4181bool range_contains_unaccepted_memory(phys_addr_t start, phys_addr_t end); 4182void accept_memory(phys_addr_t start, phys_addr_t end); 4183 4184#else 4185 4186static inline bool range_contains_unaccepted_memory(phys_addr_t start, 4187 phys_addr_t end) 4188{ 4189 return false; 4190} 4191 4192static inline void accept_memory(phys_addr_t start, phys_addr_t end) 4193{ 4194} 4195 4196#endif 4197 4198static inline bool pfn_is_unaccepted_memory(unsigned long pfn) 4199{ 4200 phys_addr_t paddr = pfn << PAGE_SHIFT; 4201 4202 return range_contains_unaccepted_memory(paddr, paddr + PAGE_SIZE); 4203} 4204 4205#endif /* _LINUX_MM_H */ 4206