Line data Source code
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 :
34 : struct mempolicy;
35 : struct anon_vma;
36 : struct anon_vma_chain;
37 : struct user_struct;
38 : struct pt_regs;
39 :
40 : extern int sysctl_page_lock_unfairness;
41 :
42 : void mm_core_init(void);
43 : void init_mm_internals(void);
44 :
45 : #ifndef CONFIG_NUMA /* Don't use mapnrs, do it properly */
46 : extern unsigned long max_mapnr;
47 :
48 : static inline void set_max_mapnr(unsigned long limit)
49 : {
50 : max_mapnr = limit;
51 : }
52 : #else
53 : static inline void set_max_mapnr(unsigned long limit) { }
54 : #endif
55 :
56 : extern atomic_long_t _totalram_pages;
57 : static inline unsigned long totalram_pages(void)
58 : {
59 282 : return (unsigned long)atomic_long_read(&_totalram_pages);
60 : }
61 :
62 : static inline void totalram_pages_inc(void)
63 : {
64 0 : atomic_long_inc(&_totalram_pages);
65 : }
66 :
67 : static inline void totalram_pages_dec(void)
68 : {
69 : atomic_long_dec(&_totalram_pages);
70 : }
71 :
72 : static inline void totalram_pages_add(long count)
73 : {
74 1 : atomic_long_add(count, &_totalram_pages);
75 : }
76 :
77 : extern void * high_memory;
78 : extern int page_cluster;
79 : extern const int page_cluster_max;
80 :
81 : #ifdef CONFIG_SYSCTL
82 : extern int sysctl_legacy_va_layout;
83 : #else
84 : #define sysctl_legacy_va_layout 0
85 : #endif
86 :
87 : #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
88 : extern const int mmap_rnd_bits_min;
89 : extern const int mmap_rnd_bits_max;
90 : extern int mmap_rnd_bits __read_mostly;
91 : #endif
92 : #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
93 : extern const int mmap_rnd_compat_bits_min;
94 : extern const int mmap_rnd_compat_bits_max;
95 : extern int mmap_rnd_compat_bits __read_mostly;
96 : #endif
97 :
98 : #include <asm/page.h>
99 : #include <asm/processor.h>
100 :
101 : #ifndef __pa_symbol
102 : #define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0))
103 : #endif
104 :
105 : #ifndef page_to_virt
106 : #define page_to_virt(x) __va(PFN_PHYS(page_to_pfn(x)))
107 : #endif
108 :
109 : #ifndef lm_alias
110 : #define lm_alias(x) __va(__pa_symbol(x))
111 : #endif
112 :
113 : /*
114 : * To prevent common memory management code establishing
115 : * a zero page mapping on a read fault.
116 : * This macro should be defined within <asm/pgtable.h>.
117 : * s390 does this to prevent multiplexing of hardware bits
118 : * related to the physical page in case of virtualization.
119 : */
120 : #ifndef mm_forbids_zeropage
121 : #define mm_forbids_zeropage(X) (0)
122 : #endif
123 :
124 : /*
125 : * On some architectures it is expensive to call memset() for small sizes.
126 : * If an architecture decides to implement their own version of
127 : * mm_zero_struct_page they should wrap the defines below in a #ifndef and
128 : * define their own version of this macro in <asm/pgtable.h>
129 : */
130 : #if BITS_PER_LONG == 64
131 : /* This function must be updated when the size of struct page grows above 96
132 : * or reduces below 56. The idea that compiler optimizes out switch()
133 : * statement, and only leaves move/store instructions. Also the compiler can
134 : * combine write statements if they are both assignments and can be reordered,
135 : * this can result in several of the writes here being dropped.
136 : */
137 : #define mm_zero_struct_page(pp) __mm_zero_struct_page(pp)
138 : static inline void __mm_zero_struct_page(struct page *page)
139 : {
140 265940 : unsigned long *_pp = (void *)page;
141 :
142 : /* Check that struct page is either 56, 64, 72, 80, 88 or 96 bytes */
143 : BUILD_BUG_ON(sizeof(struct page) & 7);
144 : BUILD_BUG_ON(sizeof(struct page) < 56);
145 : BUILD_BUG_ON(sizeof(struct page) > 96);
146 :
147 : switch (sizeof(struct page)) {
148 : case 96:
149 : _pp[11] = 0;
150 : fallthrough;
151 : case 88:
152 : _pp[10] = 0;
153 : fallthrough;
154 : case 80:
155 : _pp[9] = 0;
156 : fallthrough;
157 : case 72:
158 : _pp[8] = 0;
159 : fallthrough;
160 : case 64:
161 : _pp[7] = 0;
162 : fallthrough;
163 : case 56:
164 265940 : _pp[6] = 0;
165 265940 : _pp[5] = 0;
166 265940 : _pp[4] = 0;
167 265940 : _pp[3] = 0;
168 : _pp[2] = 0;
169 : _pp[1] = 0;
170 : _pp[0] = 0;
171 : }
172 : }
173 : #else
174 : #define mm_zero_struct_page(pp) ((void)memset((pp), 0, sizeof(struct page)))
175 : #endif
176 :
177 : /*
178 : * Default maximum number of active map areas, this limits the number of vmas
179 : * per mm struct. Users can overwrite this number by sysctl but there is a
180 : * problem.
181 : *
182 : * When a program's coredump is generated as ELF format, a section is created
183 : * per a vma. In ELF, the number of sections is represented in unsigned short.
184 : * This means the number of sections should be smaller than 65535 at coredump.
185 : * Because the kernel adds some informative sections to a image of program at
186 : * generating coredump, we need some margin. The number of extra sections is
187 : * 1-3 now and depends on arch. We use "5" as safe margin, here.
188 : *
189 : * ELF extended numbering allows more than 65535 sections, so 16-bit bound is
190 : * not a hard limit any more. Although some userspace tools can be surprised by
191 : * that.
192 : */
193 : #define MAPCOUNT_ELF_CORE_MARGIN (5)
194 : #define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
195 :
196 : extern int sysctl_max_map_count;
197 :
198 : extern unsigned long sysctl_user_reserve_kbytes;
199 : extern unsigned long sysctl_admin_reserve_kbytes;
200 :
201 : extern int sysctl_overcommit_memory;
202 : extern int sysctl_overcommit_ratio;
203 : extern unsigned long sysctl_overcommit_kbytes;
204 :
205 : int overcommit_ratio_handler(struct ctl_table *, int, void *, size_t *,
206 : loff_t *);
207 : int overcommit_kbytes_handler(struct ctl_table *, int, void *, size_t *,
208 : loff_t *);
209 : int overcommit_policy_handler(struct ctl_table *, int, void *, size_t *,
210 : loff_t *);
211 :
212 : #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
213 : #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
214 : #define folio_page_idx(folio, p) (page_to_pfn(p) - folio_pfn(folio))
215 : #else
216 : #define nth_page(page,n) ((page) + (n))
217 : #define folio_page_idx(folio, p) ((p) - &(folio)->page)
218 : #endif
219 :
220 : /* to align the pointer to the (next) page boundary */
221 : #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
222 :
223 : /* to align the pointer to the (prev) page boundary */
224 : #define PAGE_ALIGN_DOWN(addr) ALIGN_DOWN(addr, PAGE_SIZE)
225 :
226 : /* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
227 : #define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)(addr), PAGE_SIZE)
228 :
229 : #define lru_to_page(head) (list_entry((head)->prev, struct page, lru))
230 : static inline struct folio *lru_to_folio(struct list_head *head)
231 : {
232 0 : return list_entry((head)->prev, struct folio, lru);
233 : }
234 :
235 : void 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 :
247 : struct vm_area_struct *vm_area_alloc(struct mm_struct *);
248 : struct vm_area_struct *vm_area_dup(struct vm_area_struct *);
249 : void vm_area_free(struct vm_area_struct *);
250 : /* Use only if VMA has no other users */
251 : void __vm_area_free(struct vm_area_struct *vma);
252 :
253 : #ifndef CONFIG_MMU
254 : extern struct rb_root nommu_region_tree;
255 : extern struct rw_semaphore nommu_region_sem;
256 :
257 : extern 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_0 BIT(VM_HIGH_ARCH_BIT_0)
323 : #define VM_HIGH_ARCH_1 BIT(VM_HIGH_ARCH_BIT_1)
324 : #define VM_HIGH_ARCH_2 BIT(VM_HIGH_ARCH_BIT_2)
325 : #define VM_HIGH_ARCH_3 BIT(VM_HIGH_ARCH_BIT_3)
326 : #define VM_HIGH_ARCH_4 BIT(VM_HIGH_ARCH_BIT_4)
327 : #endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */
328 :
329 : #ifdef CONFIG_ARCH_HAS_PKEYS
330 : # define VM_PKEY_SHIFT VM_HIGH_ARCH_BIT_0
331 : # define VM_PKEY_BIT0 VM_HIGH_ARCH_0 /* A protection key is a 4-bit value */
332 : # define VM_PKEY_BIT1 VM_HIGH_ARCH_1 /* on x86 and 5-bit value on ppc64 */
333 : # define VM_PKEY_BIT2 VM_HIGH_ARCH_2
334 : # define VM_PKEY_BIT3 VM_HIGH_ARCH_3
335 : #ifdef CONFIG_PPC
336 : # define VM_PKEY_BIT4 VM_HIGH_ARCH_4
337 : #else
338 : # define VM_PKEY_BIT4 0
339 : #endif
340 : #endif /* CONFIG_ARCH_HAS_PKEYS */
341 :
342 : #if defined(CONFIG_X86)
343 : # define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */
344 : #elif defined(CONFIG_PPC)
345 : # define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */
346 : #elif defined(CONFIG_PARISC)
347 : # define VM_GROWSUP VM_ARCH_1
348 : #elif defined(CONFIG_IA64)
349 : # define VM_GROWSUP VM_ARCH_1
350 : #elif defined(CONFIG_SPARC64)
351 : # define VM_SPARC_ADI VM_ARCH_1 /* Uses ADI tag for access control */
352 : # define VM_ARCH_CLEAR VM_SPARC_ADI
353 : #elif defined(CONFIG_ARM64)
354 : # define VM_ARM64_BTI VM_ARCH_1 /* BTI guarded page, a.k.a. GP bit */
355 : # define VM_ARCH_CLEAR VM_ARM64_BTI
356 : #elif !defined(CONFIG_MMU)
357 : # define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */
358 : #endif
359 :
360 : #if defined(CONFIG_ARM64_MTE)
361 : # define VM_MTE VM_HIGH_ARCH_0 /* Use Tagged memory for access control */
362 : # define VM_MTE_ALLOWED VM_HIGH_ARCH_1 /* Tagged memory permitted */
363 : #else
364 : # define VM_MTE VM_NONE
365 : # define VM_MTE_ALLOWED VM_NONE
366 : #endif
367 :
368 : #ifndef VM_GROWSUP
369 : # define VM_GROWSUP VM_NONE
370 : #endif
371 :
372 : #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
373 : # define VM_UFFD_MINOR_BIT 37
374 : # define VM_UFFD_MINOR BIT(VM_UFFD_MINOR_BIT) /* UFFD minor faults */
375 : #else /* !CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
376 : # define VM_UFFD_MINOR VM_NONE
377 : #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
378 :
379 : /* Bits set in the VMA until the stack is in its final location */
380 : #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ)
381 :
382 : #define TASK_EXEC ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0)
383 :
384 : /* Common data flag combinations */
385 : #define VM_DATA_FLAGS_TSK_EXEC (VM_READ | VM_WRITE | TASK_EXEC | \
386 : VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
387 : #define VM_DATA_FLAGS_NON_EXEC (VM_READ | VM_WRITE | VM_MAYREAD | \
388 : VM_MAYWRITE | VM_MAYEXEC)
389 : #define VM_DATA_FLAGS_EXEC (VM_READ | VM_WRITE | VM_EXEC | \
390 : VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
391 :
392 : #ifndef VM_DATA_DEFAULT_FLAGS /* arch can override this */
393 : #define VM_DATA_DEFAULT_FLAGS VM_DATA_FLAGS_EXEC
394 : #endif
395 :
396 : #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */
397 : #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
398 : #endif
399 :
400 : #ifdef CONFIG_STACK_GROWSUP
401 : #define VM_STACK VM_GROWSUP
402 : #else
403 : #define VM_STACK VM_GROWSDOWN
404 : #endif
405 :
406 : #define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
407 :
408 : /* VMA basic access permission flags */
409 : #define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC)
410 :
411 :
412 : /*
413 : * Special vmas that are non-mergable, non-mlock()able.
414 : */
415 : #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP)
416 :
417 : /* This mask prevents VMA from being scanned with khugepaged */
418 : #define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB)
419 :
420 : /* This mask defines which mm->def_flags a process can inherit its parent */
421 : #define VM_INIT_DEF_MASK VM_NOHUGEPAGE
422 :
423 : /* This mask represents all the VMA flag bits used by mlock */
424 : #define VM_LOCKED_MASK (VM_LOCKED | VM_LOCKONFAULT)
425 :
426 : /* Arch-specific flags to clear when updating VM flags on protection change */
427 : #ifndef VM_ARCH_CLEAR
428 : # define VM_ARCH_CLEAR VM_NONE
429 : #endif
430 : #define VM_FLAGS_CLEAR (ARCH_VM_PKEY_FLAGS | VM_ARCH_CLEAR)
431 :
432 : /*
433 : * mapping from the currently active vm_flags protection bits (the
434 : * low four bits) to a page protection mask..
435 : */
436 :
437 : /*
438 : * The default fault flags that should be used by most of the
439 : * arch-specific page fault handlers.
440 : */
441 : #define FAULT_FLAG_DEFAULT (FAULT_FLAG_ALLOW_RETRY | \
442 : FAULT_FLAG_KILLABLE | \
443 : FAULT_FLAG_INTERRUPTIBLE)
444 :
445 : /**
446 : * fault_flag_allow_retry_first - check ALLOW_RETRY the first time
447 : * @flags: Fault flags.
448 : *
449 : * This is mostly used for places where we want to try to avoid taking
450 : * the mmap_lock for too long a time when waiting for another condition
451 : * to change, in which case we can try to be polite to release the
452 : * mmap_lock in the first round to avoid potential starvation of other
453 : * processes that would also want the mmap_lock.
454 : *
455 : * Return: true if the page fault allows retry and this is the first
456 : * attempt of the fault handling; false otherwise.
457 : */
458 : static inline bool fault_flag_allow_retry_first(enum fault_flag flags)
459 : {
460 0 : return (flags & FAULT_FLAG_ALLOW_RETRY) &&
461 : (!(flags & FAULT_FLAG_TRIED));
462 : }
463 :
464 : #define FAULT_FLAG_TRACE \
465 : { FAULT_FLAG_WRITE, "WRITE" }, \
466 : { FAULT_FLAG_MKWRITE, "MKWRITE" }, \
467 : { FAULT_FLAG_ALLOW_RETRY, "ALLOW_RETRY" }, \
468 : { FAULT_FLAG_RETRY_NOWAIT, "RETRY_NOWAIT" }, \
469 : { FAULT_FLAG_KILLABLE, "KILLABLE" }, \
470 : { FAULT_FLAG_TRIED, "TRIED" }, \
471 : { FAULT_FLAG_USER, "USER" }, \
472 : { FAULT_FLAG_REMOTE, "REMOTE" }, \
473 : { FAULT_FLAG_INSTRUCTION, "INSTRUCTION" }, \
474 : { FAULT_FLAG_INTERRUPTIBLE, "INTERRUPTIBLE" }, \
475 : { FAULT_FLAG_VMA_LOCK, "VMA_LOCK" }
476 :
477 : /*
478 : * vm_fault is filled by the pagefault handler and passed to the vma's
479 : * ->fault function. The vma's ->fault is responsible for returning a bitmask
480 : * of VM_FAULT_xxx flags that give details about how the fault was handled.
481 : *
482 : * MM layer fills up gfp_mask for page allocations but fault handler might
483 : * alter it if its implementation requires a different allocation context.
484 : *
485 : * pgoff should be used in favour of virtual_address, if possible.
486 : */
487 : struct vm_fault {
488 : const struct {
489 : struct vm_area_struct *vma; /* Target VMA */
490 : gfp_t gfp_mask; /* gfp mask to be used for allocations */
491 : pgoff_t pgoff; /* Logical page offset based on vma */
492 : unsigned long address; /* Faulting virtual address - masked */
493 : unsigned long real_address; /* Faulting virtual address - unmasked */
494 : };
495 : enum fault_flag flags; /* FAULT_FLAG_xxx flags
496 : * XXX: should really be 'const' */
497 : pmd_t *pmd; /* Pointer to pmd entry matching
498 : * the 'address' */
499 : pud_t *pud; /* Pointer to pud entry matching
500 : * the 'address'
501 : */
502 : union {
503 : pte_t orig_pte; /* Value of PTE at the time of fault */
504 : pmd_t orig_pmd; /* Value of PMD at the time of fault,
505 : * used by PMD fault only.
506 : */
507 : };
508 :
509 : struct page *cow_page; /* Page handler may use for COW fault */
510 : struct page *page; /* ->fault handlers should return a
511 : * page here, unless VM_FAULT_NOPAGE
512 : * is set (which is also implied by
513 : * VM_FAULT_ERROR).
514 : */
515 : /* These three entries are valid only while holding ptl lock */
516 : pte_t *pte; /* Pointer to pte entry matching
517 : * the 'address'. NULL if the page
518 : * table hasn't been allocated.
519 : */
520 : spinlock_t *ptl; /* Page table lock.
521 : * Protects pte page table if 'pte'
522 : * is not NULL, otherwise pmd.
523 : */
524 : pgtable_t prealloc_pte; /* Pre-allocated pte page table.
525 : * vm_ops->map_pages() sets up a page
526 : * table from atomic context.
527 : * do_fault_around() pre-allocates
528 : * page table to avoid allocation from
529 : * atomic context.
530 : */
531 : };
532 :
533 : /* page entry size for vm->huge_fault() */
534 : enum page_entry_size {
535 : PE_SIZE_PTE = 0,
536 : PE_SIZE_PMD,
537 : PE_SIZE_PUD,
538 : };
539 :
540 : /*
541 : * These are the virtual MM functions - opening of an area, closing and
542 : * unmapping it (needed to keep files on disk up-to-date etc), pointer
543 : * to the functions called when a no-page or a wp-page exception occurs.
544 : */
545 : struct vm_operations_struct {
546 : void (*open)(struct vm_area_struct * area);
547 : /**
548 : * @close: Called when the VMA is being removed from the MM.
549 : * Context: User context. May sleep. Caller holds mmap_lock.
550 : */
551 : void (*close)(struct vm_area_struct * area);
552 : /* Called any time before splitting to check if it's allowed */
553 : int (*may_split)(struct vm_area_struct *area, unsigned long addr);
554 : int (*mremap)(struct vm_area_struct *area);
555 : /*
556 : * Called by mprotect() to make driver-specific permission
557 : * checks before mprotect() is finalised. The VMA must not
558 : * be modified. Returns 0 if mprotect() can proceed.
559 : */
560 : int (*mprotect)(struct vm_area_struct *vma, unsigned long start,
561 : unsigned long end, unsigned long newflags);
562 : vm_fault_t (*fault)(struct vm_fault *vmf);
563 : vm_fault_t (*huge_fault)(struct vm_fault *vmf,
564 : enum page_entry_size pe_size);
565 : vm_fault_t (*map_pages)(struct vm_fault *vmf,
566 : pgoff_t start_pgoff, pgoff_t end_pgoff);
567 : unsigned long (*pagesize)(struct vm_area_struct * area);
568 :
569 : /* notification that a previously read-only page is about to become
570 : * writable, if an error is returned it will cause a SIGBUS */
571 : vm_fault_t (*page_mkwrite)(struct vm_fault *vmf);
572 :
573 : /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */
574 : vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf);
575 :
576 : /* called by access_process_vm when get_user_pages() fails, typically
577 : * for use by special VMAs. See also generic_access_phys() for a generic
578 : * implementation useful for any iomem mapping.
579 : */
580 : int (*access)(struct vm_area_struct *vma, unsigned long addr,
581 : void *buf, int len, int write);
582 :
583 : /* Called by the /proc/PID/maps code to ask the vma whether it
584 : * has a special name. Returning non-NULL will also cause this
585 : * vma to be dumped unconditionally. */
586 : const char *(*name)(struct vm_area_struct *vma);
587 :
588 : #ifdef CONFIG_NUMA
589 : /*
590 : * set_policy() op must add a reference to any non-NULL @new mempolicy
591 : * to hold the policy upon return. Caller should pass NULL @new to
592 : * remove a policy and fall back to surrounding context--i.e. do not
593 : * install a MPOL_DEFAULT policy, nor the task or system default
594 : * mempolicy.
595 : */
596 : int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
597 :
598 : /*
599 : * get_policy() op must add reference [mpol_get()] to any policy at
600 : * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure
601 : * in mm/mempolicy.c will do this automatically.
602 : * get_policy() must NOT add a ref if the policy at (vma,addr) is not
603 : * marked as MPOL_SHARED. vma policies are protected by the mmap_lock.
604 : * If no [shared/vma] mempolicy exists at the addr, get_policy() op
605 : * must return NULL--i.e., do not "fallback" to task or system default
606 : * policy.
607 : */
608 : struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
609 : unsigned long addr);
610 : #endif
611 : /*
612 : * Called by vm_normal_page() for special PTEs to find the
613 : * page for @addr. This is useful if the default behavior
614 : * (using pte_page()) would not find the correct page.
615 : */
616 : struct page *(*find_special_page)(struct vm_area_struct *vma,
617 : unsigned long addr);
618 : };
619 :
620 : #ifdef CONFIG_NUMA_BALANCING
621 : static inline void vma_numab_state_init(struct vm_area_struct *vma)
622 : {
623 : vma->numab_state = NULL;
624 : }
625 : static inline void vma_numab_state_free(struct vm_area_struct *vma)
626 : {
627 : kfree(vma->numab_state);
628 : }
629 : #else
630 : static inline void vma_numab_state_init(struct vm_area_struct *vma) {}
631 : static inline void vma_numab_state_free(struct vm_area_struct *vma) {}
632 : #endif /* CONFIG_NUMA_BALANCING */
633 :
634 : #ifdef CONFIG_PER_VMA_LOCK
635 : /*
636 : * Try to read-lock a vma. The function is allowed to occasionally yield false
637 : * locked result to avoid performance overhead, in which case we fall back to
638 : * using mmap_lock. The function should never yield false unlocked result.
639 : */
640 : static inline bool vma_start_read(struct vm_area_struct *vma)
641 : {
642 : /* Check before locking. A race might cause false locked result. */
643 : if (vma->vm_lock_seq == READ_ONCE(vma->vm_mm->mm_lock_seq))
644 : return false;
645 :
646 : if (unlikely(down_read_trylock(&vma->vm_lock->lock) == 0))
647 : return false;
648 :
649 : /*
650 : * Overflow might produce false locked result.
651 : * False unlocked result is impossible because we modify and check
652 : * vma->vm_lock_seq under vma->vm_lock protection and mm->mm_lock_seq
653 : * modification invalidates all existing locks.
654 : */
655 : if (unlikely(vma->vm_lock_seq == READ_ONCE(vma->vm_mm->mm_lock_seq))) {
656 : up_read(&vma->vm_lock->lock);
657 : return false;
658 : }
659 : return true;
660 : }
661 :
662 : static inline void vma_end_read(struct vm_area_struct *vma)
663 : {
664 : rcu_read_lock(); /* keeps vma alive till the end of up_read */
665 : up_read(&vma->vm_lock->lock);
666 : rcu_read_unlock();
667 : }
668 :
669 : static bool __is_vma_write_locked(struct vm_area_struct *vma, int *mm_lock_seq)
670 : {
671 : mmap_assert_write_locked(vma->vm_mm);
672 :
673 : /*
674 : * current task is holding mmap_write_lock, both vma->vm_lock_seq and
675 : * mm->mm_lock_seq can't be concurrently modified.
676 : */
677 : *mm_lock_seq = READ_ONCE(vma->vm_mm->mm_lock_seq);
678 : return (vma->vm_lock_seq == *mm_lock_seq);
679 : }
680 :
681 : static inline void vma_start_write(struct vm_area_struct *vma)
682 : {
683 : int mm_lock_seq;
684 :
685 : if (__is_vma_write_locked(vma, &mm_lock_seq))
686 : return;
687 :
688 : down_write(&vma->vm_lock->lock);
689 : vma->vm_lock_seq = mm_lock_seq;
690 : up_write(&vma->vm_lock->lock);
691 : }
692 :
693 : static inline bool vma_try_start_write(struct vm_area_struct *vma)
694 : {
695 : int mm_lock_seq;
696 :
697 : if (__is_vma_write_locked(vma, &mm_lock_seq))
698 : return true;
699 :
700 : if (!down_write_trylock(&vma->vm_lock->lock))
701 : return false;
702 :
703 : vma->vm_lock_seq = mm_lock_seq;
704 : up_write(&vma->vm_lock->lock);
705 : return true;
706 : }
707 :
708 : static inline void vma_assert_write_locked(struct vm_area_struct *vma)
709 : {
710 : int mm_lock_seq;
711 :
712 : VM_BUG_ON_VMA(!__is_vma_write_locked(vma, &mm_lock_seq), vma);
713 : }
714 :
715 : static inline void vma_mark_detached(struct vm_area_struct *vma, bool detached)
716 : {
717 : /* When detaching vma should be write-locked */
718 : if (detached)
719 : vma_assert_write_locked(vma);
720 : vma->detached = detached;
721 : }
722 :
723 : struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm,
724 : unsigned long address);
725 :
726 : #else /* CONFIG_PER_VMA_LOCK */
727 :
728 : static inline void vma_init_lock(struct vm_area_struct *vma) {}
729 : static inline bool vma_start_read(struct vm_area_struct *vma)
730 : { return false; }
731 : static inline void vma_end_read(struct vm_area_struct *vma) {}
732 : static inline void vma_start_write(struct vm_area_struct *vma) {}
733 : static inline bool vma_try_start_write(struct vm_area_struct *vma)
734 : { return true; }
735 : static inline void vma_assert_write_locked(struct vm_area_struct *vma) {}
736 : static inline void vma_mark_detached(struct vm_area_struct *vma,
737 : bool detached) {}
738 :
739 : #endif /* CONFIG_PER_VMA_LOCK */
740 :
741 : /*
742 : * WARNING: vma_init does not initialize vma->vm_lock.
743 : * Use vm_area_alloc()/vm_area_free() if vma needs locking.
744 : */
745 : static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm)
746 : {
747 : static const struct vm_operations_struct dummy_vm_ops = {};
748 :
749 0 : memset(vma, 0, sizeof(*vma));
750 0 : vma->vm_mm = mm;
751 0 : vma->vm_ops = &dummy_vm_ops;
752 0 : INIT_LIST_HEAD(&vma->anon_vma_chain);
753 0 : vma_mark_detached(vma, false);
754 0 : vma_numab_state_init(vma);
755 : }
756 :
757 : /* Use when VMA is not part of the VMA tree and needs no locking */
758 : static inline void vm_flags_init(struct vm_area_struct *vma,
759 : vm_flags_t flags)
760 : {
761 0 : ACCESS_PRIVATE(vma, __vm_flags) = flags;
762 : }
763 :
764 : /* Use when VMA is part of the VMA tree and modifications need coordination */
765 : static inline void vm_flags_reset(struct vm_area_struct *vma,
766 : vm_flags_t flags)
767 : {
768 0 : vma_start_write(vma);
769 0 : vm_flags_init(vma, flags);
770 : }
771 :
772 : static inline void vm_flags_reset_once(struct vm_area_struct *vma,
773 : vm_flags_t flags)
774 : {
775 0 : vma_start_write(vma);
776 0 : WRITE_ONCE(ACCESS_PRIVATE(vma, __vm_flags), flags);
777 : }
778 :
779 : static inline void vm_flags_set(struct vm_area_struct *vma,
780 : vm_flags_t flags)
781 : {
782 0 : vma_start_write(vma);
783 0 : ACCESS_PRIVATE(vma, __vm_flags) |= flags;
784 : }
785 :
786 : static inline void vm_flags_clear(struct vm_area_struct *vma,
787 : vm_flags_t flags)
788 : {
789 0 : vma_start_write(vma);
790 0 : ACCESS_PRIVATE(vma, __vm_flags) &= ~flags;
791 : }
792 :
793 : /*
794 : * Use only if VMA is not part of the VMA tree or has no other users and
795 : * therefore needs no locking.
796 : */
797 : static inline void __vm_flags_mod(struct vm_area_struct *vma,
798 : vm_flags_t set, vm_flags_t clear)
799 : {
800 : vm_flags_init(vma, (vma->vm_flags | set) & ~clear);
801 : }
802 :
803 : /*
804 : * Use only when the order of set/clear operations is unimportant, otherwise
805 : * use vm_flags_{set|clear} explicitly.
806 : */
807 : static inline void vm_flags_mod(struct vm_area_struct *vma,
808 : vm_flags_t set, vm_flags_t clear)
809 : {
810 : vma_start_write(vma);
811 : __vm_flags_mod(vma, set, clear);
812 : }
813 :
814 : static inline void vma_set_anonymous(struct vm_area_struct *vma)
815 : {
816 0 : vma->vm_ops = NULL;
817 : }
818 :
819 : static inline bool vma_is_anonymous(struct vm_area_struct *vma)
820 : {
821 0 : return !vma->vm_ops;
822 : }
823 :
824 : static inline bool vma_is_temporary_stack(struct vm_area_struct *vma)
825 : {
826 0 : int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP);
827 :
828 0 : if (!maybe_stack)
829 : return false;
830 :
831 0 : if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) ==
832 : VM_STACK_INCOMPLETE_SETUP)
833 : return true;
834 :
835 : return false;
836 : }
837 :
838 : static inline bool vma_is_foreign(struct vm_area_struct *vma)
839 : {
840 : if (!current->mm)
841 : return true;
842 :
843 : if (current->mm != vma->vm_mm)
844 : return true;
845 :
846 : return false;
847 : }
848 :
849 : static inline bool vma_is_accessible(struct vm_area_struct *vma)
850 : {
851 0 : return vma->vm_flags & VM_ACCESS_FLAGS;
852 : }
853 :
854 : static inline
855 : struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max)
856 : {
857 0 : return mas_find(&vmi->mas, max - 1);
858 : }
859 :
860 : static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi)
861 : {
862 : /*
863 : * Uses mas_find() to get the first VMA when the iterator starts.
864 : * Calling mas_next() could skip the first entry.
865 : */
866 0 : return mas_find(&vmi->mas, ULONG_MAX);
867 : }
868 :
869 : static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi)
870 : {
871 0 : return mas_prev(&vmi->mas, 0);
872 : }
873 :
874 : static inline unsigned long vma_iter_addr(struct vma_iterator *vmi)
875 : {
876 : return vmi->mas.index;
877 : }
878 :
879 : static inline unsigned long vma_iter_end(struct vma_iterator *vmi)
880 : {
881 0 : return vmi->mas.last + 1;
882 : }
883 : static inline int vma_iter_bulk_alloc(struct vma_iterator *vmi,
884 : unsigned long count)
885 : {
886 0 : return mas_expected_entries(&vmi->mas, count);
887 : }
888 :
889 : /* Free any unused preallocations */
890 : static inline void vma_iter_free(struct vma_iterator *vmi)
891 : {
892 0 : mas_destroy(&vmi->mas);
893 : }
894 :
895 0 : static inline int vma_iter_bulk_store(struct vma_iterator *vmi,
896 : struct vm_area_struct *vma)
897 : {
898 0 : vmi->mas.index = vma->vm_start;
899 0 : vmi->mas.last = vma->vm_end - 1;
900 0 : mas_store(&vmi->mas, vma);
901 0 : if (unlikely(mas_is_err(&vmi->mas)))
902 : return -ENOMEM;
903 :
904 0 : return 0;
905 : }
906 :
907 : static inline void vma_iter_invalidate(struct vma_iterator *vmi)
908 : {
909 0 : mas_pause(&vmi->mas);
910 : }
911 :
912 : static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr)
913 : {
914 0 : mas_set(&vmi->mas, addr);
915 : }
916 :
917 : #define for_each_vma(__vmi, __vma) \
918 : while (((__vma) = vma_next(&(__vmi))) != NULL)
919 :
920 : /* The MM code likes to work with exclusive end addresses */
921 : #define for_each_vma_range(__vmi, __vma, __end) \
922 : while (((__vma) = vma_find(&(__vmi), (__end))) != NULL)
923 :
924 : #ifdef CONFIG_SHMEM
925 : /*
926 : * The vma_is_shmem is not inline because it is used only by slow
927 : * paths in userfault.
928 : */
929 : bool vma_is_shmem(struct vm_area_struct *vma);
930 : bool vma_is_anon_shmem(struct vm_area_struct *vma);
931 : #else
932 : static inline bool vma_is_shmem(struct vm_area_struct *vma) { return false; }
933 : static inline bool vma_is_anon_shmem(struct vm_area_struct *vma) { return false; }
934 : #endif
935 :
936 : int vma_is_stack_for_current(struct vm_area_struct *vma);
937 :
938 : /* flush_tlb_range() takes a vma, not a mm, and can care about flags */
939 : #define TLB_FLUSH_VMA(mm,flags) { .vm_mm = (mm), .vm_flags = (flags) }
940 :
941 : struct mmu_gather;
942 : struct inode;
943 :
944 : /*
945 : * compound_order() can be called without holding a reference, which means
946 : * that niceties like page_folio() don't work. These callers should be
947 : * prepared to handle wild return values. For example, PG_head may be
948 : * set before _folio_order is initialised, or this may be a tail page.
949 : * See compaction.c for some good examples.
950 : */
951 : static inline unsigned int compound_order(struct page *page)
952 : {
953 0 : struct folio *folio = (struct folio *)page;
954 :
955 0 : if (!test_bit(PG_head, &folio->flags))
956 : return 0;
957 0 : return folio->_folio_order;
958 : }
959 :
960 : /**
961 : * folio_order - The allocation order of a folio.
962 : * @folio: The folio.
963 : *
964 : * A folio is composed of 2^order pages. See get_order() for the definition
965 : * of order.
966 : *
967 : * Return: The order of the folio.
968 : */
969 : static inline unsigned int folio_order(struct folio *folio)
970 : {
971 1759 : if (!folio_test_large(folio))
972 : return 0;
973 6 : return folio->_folio_order;
974 : }
975 :
976 : #include <linux/huge_mm.h>
977 :
978 : /*
979 : * Methods to modify the page usage count.
980 : *
981 : * What counts for a page usage:
982 : * - cache mapping (page->mapping)
983 : * - private data (page->private)
984 : * - page mapped in a task's page tables, each mapping
985 : * is counted separately
986 : *
987 : * Also, many kernel routines increase the page count before a critical
988 : * routine so they can be sure the page doesn't go away from under them.
989 : */
990 :
991 : /*
992 : * Drop a ref, return true if the refcount fell to zero (the page has no users)
993 : */
994 : static inline int put_page_testzero(struct page *page)
995 : {
996 : VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
997 44236 : return page_ref_dec_and_test(page);
998 : }
999 :
1000 : static inline int folio_put_testzero(struct folio *folio)
1001 : {
1002 0 : return put_page_testzero(&folio->page);
1003 : }
1004 :
1005 : /*
1006 : * Try to grab a ref unless the page has a refcount of zero, return false if
1007 : * that is the case.
1008 : * This can be called when MMU is off so it must not access
1009 : * any of the virtual mappings.
1010 : */
1011 : static inline bool get_page_unless_zero(struct page *page)
1012 : {
1013 0 : return page_ref_add_unless(page, 1, 0);
1014 : }
1015 :
1016 : static inline struct folio *folio_get_nontail_page(struct page *page)
1017 : {
1018 0 : if (unlikely(!get_page_unless_zero(page)))
1019 : return NULL;
1020 : return (struct folio *)page;
1021 : }
1022 :
1023 : extern int page_is_ram(unsigned long pfn);
1024 :
1025 : enum {
1026 : REGION_INTERSECTS,
1027 : REGION_DISJOINT,
1028 : REGION_MIXED,
1029 : };
1030 :
1031 : int region_intersects(resource_size_t offset, size_t size, unsigned long flags,
1032 : unsigned long desc);
1033 :
1034 : /* Support for virtually mapped pages */
1035 : struct page *vmalloc_to_page(const void *addr);
1036 : unsigned long vmalloc_to_pfn(const void *addr);
1037 :
1038 : /*
1039 : * Determine if an address is within the vmalloc range
1040 : *
1041 : * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
1042 : * is no special casing required.
1043 : */
1044 :
1045 : #ifndef is_ioremap_addr
1046 : #define is_ioremap_addr(x) is_vmalloc_addr(x)
1047 : #endif
1048 :
1049 : #ifdef CONFIG_MMU
1050 : extern bool is_vmalloc_addr(const void *x);
1051 : extern int is_vmalloc_or_module_addr(const void *x);
1052 : #else
1053 : static inline bool is_vmalloc_addr(const void *x)
1054 : {
1055 : return false;
1056 : }
1057 : static inline int is_vmalloc_or_module_addr(const void *x)
1058 : {
1059 : return 0;
1060 : }
1061 : #endif
1062 :
1063 : /*
1064 : * How many times the entire folio is mapped as a single unit (eg by a
1065 : * PMD or PUD entry). This is probably not what you want, except for
1066 : * debugging purposes - it does not include PTE-mapped sub-pages; look
1067 : * at folio_mapcount() or page_mapcount() or total_mapcount() instead.
1068 : */
1069 : static inline int folio_entire_mapcount(struct folio *folio)
1070 : {
1071 : VM_BUG_ON_FOLIO(!folio_test_large(folio), folio);
1072 0 : return atomic_read(&folio->_entire_mapcount) + 1;
1073 : }
1074 :
1075 : /*
1076 : * The atomic page->_mapcount, starts from -1: so that transitions
1077 : * both from it and to it can be tracked, using atomic_inc_and_test
1078 : * and atomic_add_negative(-1).
1079 : */
1080 : static inline void page_mapcount_reset(struct page *page)
1081 : {
1082 531880 : atomic_set(&(page)->_mapcount, -1);
1083 : }
1084 :
1085 : /**
1086 : * page_mapcount() - Number of times this precise page is mapped.
1087 : * @page: The page.
1088 : *
1089 : * The number of times this page is mapped. If this page is part of
1090 : * a large folio, it includes the number of times this page is mapped
1091 : * as part of that folio.
1092 : *
1093 : * The result is undefined for pages which cannot be mapped into userspace.
1094 : * For example SLAB or special types of pages. See function page_has_type().
1095 : * They use this field in struct page differently.
1096 : */
1097 0 : static inline int page_mapcount(struct page *page)
1098 : {
1099 0 : int mapcount = atomic_read(&page->_mapcount) + 1;
1100 :
1101 0 : if (unlikely(PageCompound(page)))
1102 0 : mapcount += folio_entire_mapcount(page_folio(page));
1103 :
1104 0 : return mapcount;
1105 : }
1106 :
1107 : int folio_total_mapcount(struct folio *folio);
1108 :
1109 : /**
1110 : * folio_mapcount() - Calculate the number of mappings of this folio.
1111 : * @folio: The folio.
1112 : *
1113 : * A large folio tracks both how many times the entire folio is mapped,
1114 : * and how many times each individual page in the folio is mapped.
1115 : * This function calculates the total number of times the folio is
1116 : * mapped.
1117 : *
1118 : * Return: The number of times this folio is mapped.
1119 : */
1120 : static inline int folio_mapcount(struct folio *folio)
1121 : {
1122 0 : if (likely(!folio_test_large(folio)))
1123 0 : return atomic_read(&folio->_mapcount) + 1;
1124 0 : return folio_total_mapcount(folio);
1125 : }
1126 :
1127 0 : static inline int total_mapcount(struct page *page)
1128 : {
1129 0 : if (likely(!PageCompound(page)))
1130 0 : return atomic_read(&page->_mapcount) + 1;
1131 0 : return folio_total_mapcount(page_folio(page));
1132 : }
1133 :
1134 : static inline bool folio_large_is_mapped(struct folio *folio)
1135 : {
1136 : /*
1137 : * Reading _entire_mapcount below could be omitted if hugetlb
1138 : * participated in incrementing nr_pages_mapped when compound mapped.
1139 : */
1140 0 : return atomic_read(&folio->_nr_pages_mapped) > 0 ||
1141 0 : atomic_read(&folio->_entire_mapcount) >= 0;
1142 : }
1143 :
1144 : /**
1145 : * folio_mapped - Is this folio mapped into userspace?
1146 : * @folio: The folio.
1147 : *
1148 : * Return: True if any page in this folio is referenced by user page tables.
1149 : */
1150 : static inline bool folio_mapped(struct folio *folio)
1151 : {
1152 0 : if (likely(!folio_test_large(folio)))
1153 0 : return atomic_read(&folio->_mapcount) >= 0;
1154 0 : return folio_large_is_mapped(folio);
1155 : }
1156 :
1157 : /*
1158 : * Return true if this page is mapped into pagetables.
1159 : * For compound page it returns true if any sub-page of compound page is mapped,
1160 : * even if this particular sub-page is not itself mapped by any PTE or PMD.
1161 : */
1162 0 : static inline bool page_mapped(struct page *page)
1163 : {
1164 0 : if (likely(!PageCompound(page)))
1165 0 : return atomic_read(&page->_mapcount) >= 0;
1166 0 : return folio_large_is_mapped(page_folio(page));
1167 : }
1168 :
1169 : static inline struct page *virt_to_head_page(const void *x)
1170 : {
1171 0 : struct page *page = virt_to_page(x);
1172 :
1173 0 : return compound_head(page);
1174 : }
1175 :
1176 : static inline struct folio *virt_to_folio(const void *x)
1177 : {
1178 185378 : struct page *page = virt_to_page(x);
1179 :
1180 92689 : return page_folio(page);
1181 : }
1182 :
1183 : void __folio_put(struct folio *folio);
1184 :
1185 : void put_pages_list(struct list_head *pages);
1186 :
1187 : void split_page(struct page *page, unsigned int order);
1188 : void folio_copy(struct folio *dst, struct folio *src);
1189 :
1190 : unsigned long nr_free_buffer_pages(void);
1191 :
1192 : /*
1193 : * Compound pages have a destructor function. Provide a
1194 : * prototype for that function and accessor functions.
1195 : * These are _only_ valid on the head of a compound page.
1196 : */
1197 : typedef void compound_page_dtor(struct page *);
1198 :
1199 : /* Keep the enum in sync with compound_page_dtors array in mm/page_alloc.c */
1200 : enum compound_dtor_id {
1201 : NULL_COMPOUND_DTOR,
1202 : COMPOUND_PAGE_DTOR,
1203 : #ifdef CONFIG_HUGETLB_PAGE
1204 : HUGETLB_PAGE_DTOR,
1205 : #endif
1206 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1207 : TRANSHUGE_PAGE_DTOR,
1208 : #endif
1209 : NR_COMPOUND_DTORS,
1210 : };
1211 : extern compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS];
1212 :
1213 : static inline void set_compound_page_dtor(struct page *page,
1214 : enum compound_dtor_id compound_dtor)
1215 : {
1216 102 : struct folio *folio = (struct folio *)page;
1217 :
1218 : VM_BUG_ON_PAGE(compound_dtor >= NR_COMPOUND_DTORS, page);
1219 : VM_BUG_ON_PAGE(!PageHead(page), page);
1220 102 : folio->_folio_dtor = compound_dtor;
1221 : }
1222 :
1223 : static inline void folio_set_compound_dtor(struct folio *folio,
1224 : enum compound_dtor_id compound_dtor)
1225 : {
1226 : VM_BUG_ON_FOLIO(compound_dtor >= NR_COMPOUND_DTORS, folio);
1227 : folio->_folio_dtor = compound_dtor;
1228 : }
1229 :
1230 : void destroy_large_folio(struct folio *folio);
1231 :
1232 : static inline void set_compound_order(struct page *page, unsigned int order)
1233 : {
1234 102 : struct folio *folio = (struct folio *)page;
1235 :
1236 102 : folio->_folio_order = order;
1237 : #ifdef CONFIG_64BIT
1238 102 : folio->_folio_nr_pages = 1U << order;
1239 : #endif
1240 : }
1241 :
1242 : /* Returns the number of bytes in this potentially compound page. */
1243 : static inline unsigned long page_size(struct page *page)
1244 : {
1245 0 : return PAGE_SIZE << compound_order(page);
1246 : }
1247 :
1248 : /* Returns the number of bits needed for the number of bytes in a page */
1249 : static inline unsigned int page_shift(struct page *page)
1250 : {
1251 : return PAGE_SHIFT + compound_order(page);
1252 : }
1253 :
1254 : /**
1255 : * thp_order - Order of a transparent huge page.
1256 : * @page: Head page of a transparent huge page.
1257 : */
1258 : static inline unsigned int thp_order(struct page *page)
1259 : {
1260 : VM_BUG_ON_PGFLAGS(PageTail(page), page);
1261 0 : return compound_order(page);
1262 : }
1263 :
1264 : /**
1265 : * thp_size - Size of a transparent huge page.
1266 : * @page: Head page of a transparent huge page.
1267 : *
1268 : * Return: Number of bytes in this page.
1269 : */
1270 : static inline unsigned long thp_size(struct page *page)
1271 : {
1272 0 : return PAGE_SIZE << thp_order(page);
1273 : }
1274 :
1275 : void free_compound_page(struct page *page);
1276 :
1277 : #ifdef CONFIG_MMU
1278 : /*
1279 : * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when
1280 : * servicing faults for write access. In the normal case, do always want
1281 : * pte_mkwrite. But get_user_pages can cause write faults for mappings
1282 : * that do not have writing enabled, when used by access_process_vm.
1283 : */
1284 : static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
1285 : {
1286 0 : if (likely(vma->vm_flags & VM_WRITE))
1287 : pte = pte_mkwrite(pte);
1288 : return pte;
1289 : }
1290 :
1291 : vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page);
1292 : void do_set_pte(struct vm_fault *vmf, struct page *page, unsigned long addr);
1293 :
1294 : vm_fault_t finish_fault(struct vm_fault *vmf);
1295 : vm_fault_t finish_mkwrite_fault(struct vm_fault *vmf);
1296 : #endif
1297 :
1298 : /*
1299 : * Multiple processes may "see" the same page. E.g. for untouched
1300 : * mappings of /dev/null, all processes see the same page full of
1301 : * zeroes, and text pages of executables and shared libraries have
1302 : * only one copy in memory, at most, normally.
1303 : *
1304 : * For the non-reserved pages, page_count(page) denotes a reference count.
1305 : * page_count() == 0 means the page is free. page->lru is then used for
1306 : * freelist management in the buddy allocator.
1307 : * page_count() > 0 means the page has been allocated.
1308 : *
1309 : * Pages are allocated by the slab allocator in order to provide memory
1310 : * to kmalloc and kmem_cache_alloc. In this case, the management of the
1311 : * page, and the fields in 'struct page' are the responsibility of mm/slab.c
1312 : * unless a particular usage is carefully commented. (the responsibility of
1313 : * freeing the kmalloc memory is the caller's, of course).
1314 : *
1315 : * A page may be used by anyone else who does a __get_free_page().
1316 : * In this case, page_count still tracks the references, and should only
1317 : * be used through the normal accessor functions. The top bits of page->flags
1318 : * and page->virtual store page management information, but all other fields
1319 : * are unused and could be used privately, carefully. The management of this
1320 : * page is the responsibility of the one who allocated it, and those who have
1321 : * subsequently been given references to it.
1322 : *
1323 : * The other pages (we may call them "pagecache pages") are completely
1324 : * managed by the Linux memory manager: I/O, buffers, swapping etc.
1325 : * The following discussion applies only to them.
1326 : *
1327 : * A pagecache page contains an opaque `private' member, which belongs to the
1328 : * page's address_space. Usually, this is the address of a circular list of
1329 : * the page's disk buffers. PG_private must be set to tell the VM to call
1330 : * into the filesystem to release these pages.
1331 : *
1332 : * A page may belong to an inode's memory mapping. In this case, page->mapping
1333 : * is the pointer to the inode, and page->index is the file offset of the page,
1334 : * in units of PAGE_SIZE.
1335 : *
1336 : * If pagecache pages are not associated with an inode, they are said to be
1337 : * anonymous pages. These may become associated with the swapcache, and in that
1338 : * case PG_swapcache is set, and page->private is an offset into the swapcache.
1339 : *
1340 : * In either case (swapcache or inode backed), the pagecache itself holds one
1341 : * reference to the page. Setting PG_private should also increment the
1342 : * refcount. The each user mapping also has a reference to the page.
1343 : *
1344 : * The pagecache pages are stored in a per-mapping radix tree, which is
1345 : * rooted at mapping->i_pages, and indexed by offset.
1346 : * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
1347 : * lists, we instead now tag pages as dirty/writeback in the radix tree.
1348 : *
1349 : * All pagecache pages may be subject to I/O:
1350 : * - inode pages may need to be read from disk,
1351 : * - inode pages which have been modified and are MAP_SHARED may need
1352 : * to be written back to the inode on disk,
1353 : * - anonymous pages (including MAP_PRIVATE file mappings) which have been
1354 : * modified may need to be swapped out to swap space and (later) to be read
1355 : * back into memory.
1356 : */
1357 :
1358 : #if defined(CONFIG_ZONE_DEVICE) && defined(CONFIG_FS_DAX)
1359 : DECLARE_STATIC_KEY_FALSE(devmap_managed_key);
1360 :
1361 : bool __put_devmap_managed_page_refs(struct page *page, int refs);
1362 : static inline bool put_devmap_managed_page_refs(struct page *page, int refs)
1363 : {
1364 : if (!static_branch_unlikely(&devmap_managed_key))
1365 : return false;
1366 : if (!is_zone_device_page(page))
1367 : return false;
1368 : return __put_devmap_managed_page_refs(page, refs);
1369 : }
1370 : #else /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
1371 : static inline bool put_devmap_managed_page_refs(struct page *page, int refs)
1372 : {
1373 : return false;
1374 : }
1375 : #endif /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
1376 :
1377 : static inline bool put_devmap_managed_page(struct page *page)
1378 : {
1379 0 : return put_devmap_managed_page_refs(page, 1);
1380 : }
1381 :
1382 : /* 127: arbitrary random number, small enough to assemble well */
1383 : #define folio_ref_zero_or_close_to_overflow(folio) \
1384 : ((unsigned int) folio_ref_count(folio) + 127u <= 127u)
1385 :
1386 : /**
1387 : * folio_get - Increment the reference count on a folio.
1388 : * @folio: The folio.
1389 : *
1390 : * Context: May be called in any context, as long as you know that
1391 : * you have a refcount on the folio. If you do not already have one,
1392 : * folio_try_get() may be the right interface for you to use.
1393 : */
1394 : static inline void folio_get(struct folio *folio)
1395 : {
1396 : VM_BUG_ON_FOLIO(folio_ref_zero_or_close_to_overflow(folio), folio);
1397 0 : folio_ref_inc(folio);
1398 : }
1399 :
1400 : static inline void get_page(struct page *page)
1401 : {
1402 0 : folio_get(page_folio(page));
1403 : }
1404 :
1405 0 : static inline __must_check bool try_get_page(struct page *page)
1406 : {
1407 0 : page = compound_head(page);
1408 0 : if (WARN_ON_ONCE(page_ref_count(page) <= 0))
1409 : return false;
1410 0 : page_ref_inc(page);
1411 0 : return true;
1412 : }
1413 :
1414 : /**
1415 : * folio_put - Decrement the reference count on a folio.
1416 : * @folio: The folio.
1417 : *
1418 : * If the folio's reference count reaches zero, the memory will be
1419 : * released back to the page allocator and may be used by another
1420 : * allocation immediately. Do not access the memory or the struct folio
1421 : * after calling folio_put() unless you can be sure that it wasn't the
1422 : * last reference.
1423 : *
1424 : * Context: May be called in process or interrupt context, but not in NMI
1425 : * context. May be called while holding a spinlock.
1426 : */
1427 : static inline void folio_put(struct folio *folio)
1428 : {
1429 0 : if (folio_put_testzero(folio))
1430 0 : __folio_put(folio);
1431 : }
1432 :
1433 : /**
1434 : * folio_put_refs - Reduce the reference count on a folio.
1435 : * @folio: The folio.
1436 : * @refs: The amount to subtract from the folio's reference count.
1437 : *
1438 : * If the folio's reference count reaches zero, the memory will be
1439 : * released back to the page allocator and may be used by another
1440 : * allocation immediately. Do not access the memory or the struct folio
1441 : * after calling folio_put_refs() unless you can be sure that these weren't
1442 : * the last references.
1443 : *
1444 : * Context: May be called in process or interrupt context, but not in NMI
1445 : * context. May be called while holding a spinlock.
1446 : */
1447 : static inline void folio_put_refs(struct folio *folio, int refs)
1448 : {
1449 0 : if (folio_ref_sub_and_test(folio, refs))
1450 0 : __folio_put(folio);
1451 : }
1452 :
1453 : /*
1454 : * union release_pages_arg - an array of pages or folios
1455 : *
1456 : * release_pages() releases a simple array of multiple pages, and
1457 : * accepts various different forms of said page array: either
1458 : * a regular old boring array of pages, an array of folios, or
1459 : * an array of encoded page pointers.
1460 : *
1461 : * The transparent union syntax for this kind of "any of these
1462 : * argument types" is all kinds of ugly, so look away.
1463 : */
1464 : typedef union {
1465 : struct page **pages;
1466 : struct folio **folios;
1467 : struct encoded_page **encoded_pages;
1468 : } release_pages_arg __attribute__ ((__transparent_union__));
1469 :
1470 : void release_pages(release_pages_arg, int nr);
1471 :
1472 : /**
1473 : * folios_put - Decrement the reference count on an array of folios.
1474 : * @folios: The folios.
1475 : * @nr: How many folios there are.
1476 : *
1477 : * Like folio_put(), but for an array of folios. This is more efficient
1478 : * than writing the loop yourself as it will optimise the locks which
1479 : * need to be taken if the folios are freed.
1480 : *
1481 : * Context: May be called in process or interrupt context, but not in NMI
1482 : * context. May be called while holding a spinlock.
1483 : */
1484 : static inline void folios_put(struct folio **folios, unsigned int nr)
1485 : {
1486 0 : release_pages(folios, nr);
1487 : }
1488 :
1489 0 : static inline void put_page(struct page *page)
1490 : {
1491 0 : struct folio *folio = page_folio(page);
1492 :
1493 : /*
1494 : * For some devmap managed pages we need to catch refcount transition
1495 : * from 2 to 1:
1496 : */
1497 0 : if (put_devmap_managed_page(&folio->page))
1498 : return;
1499 : folio_put(folio);
1500 : }
1501 :
1502 : /*
1503 : * GUP_PIN_COUNTING_BIAS, and the associated functions that use it, overload
1504 : * the page's refcount so that two separate items are tracked: the original page
1505 : * reference count, and also a new count of how many pin_user_pages() calls were
1506 : * made against the page. ("gup-pinned" is another term for the latter).
1507 : *
1508 : * With this scheme, pin_user_pages() becomes special: such pages are marked as
1509 : * distinct from normal pages. As such, the unpin_user_page() call (and its
1510 : * variants) must be used in order to release gup-pinned pages.
1511 : *
1512 : * Choice of value:
1513 : *
1514 : * By making GUP_PIN_COUNTING_BIAS a power of two, debugging of page reference
1515 : * counts with respect to pin_user_pages() and unpin_user_page() becomes
1516 : * simpler, due to the fact that adding an even power of two to the page
1517 : * refcount has the effect of using only the upper N bits, for the code that
1518 : * counts up using the bias value. This means that the lower bits are left for
1519 : * the exclusive use of the original code that increments and decrements by one
1520 : * (or at least, by much smaller values than the bias value).
1521 : *
1522 : * Of course, once the lower bits overflow into the upper bits (and this is
1523 : * OK, because subtraction recovers the original values), then visual inspection
1524 : * no longer suffices to directly view the separate counts. However, for normal
1525 : * applications that don't have huge page reference counts, this won't be an
1526 : * issue.
1527 : *
1528 : * Locking: the lockless algorithm described in folio_try_get_rcu()
1529 : * provides safe operation for get_user_pages(), page_mkclean() and
1530 : * other calls that race to set up page table entries.
1531 : */
1532 : #define GUP_PIN_COUNTING_BIAS (1U << 10)
1533 :
1534 : void unpin_user_page(struct page *page);
1535 : void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages,
1536 : bool make_dirty);
1537 : void unpin_user_page_range_dirty_lock(struct page *page, unsigned long npages,
1538 : bool make_dirty);
1539 : void unpin_user_pages(struct page **pages, unsigned long npages);
1540 :
1541 : static inline bool is_cow_mapping(vm_flags_t flags)
1542 : {
1543 0 : return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
1544 : }
1545 :
1546 : #ifndef CONFIG_MMU
1547 : static inline bool is_nommu_shared_mapping(vm_flags_t flags)
1548 : {
1549 : /*
1550 : * NOMMU shared mappings are ordinary MAP_SHARED mappings and selected
1551 : * R/O MAP_PRIVATE file mappings that are an effective R/O overlay of
1552 : * a file mapping. R/O MAP_PRIVATE mappings might still modify
1553 : * underlying memory if ptrace is active, so this is only possible if
1554 : * ptrace does not apply. Note that there is no mprotect() to upgrade
1555 : * write permissions later.
1556 : */
1557 : return flags & (VM_MAYSHARE | VM_MAYOVERLAY);
1558 : }
1559 : #endif
1560 :
1561 : #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
1562 : #define SECTION_IN_PAGE_FLAGS
1563 : #endif
1564 :
1565 : /*
1566 : * The identification function is mainly used by the buddy allocator for
1567 : * determining if two pages could be buddies. We are not really identifying
1568 : * the zone since we could be using the section number id if we do not have
1569 : * node id available in page flags.
1570 : * We only guarantee that it will return the same value for two combinable
1571 : * pages in a zone.
1572 : */
1573 : static inline int page_zone_id(struct page *page)
1574 : {
1575 3262 : return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK;
1576 : }
1577 :
1578 : #ifdef NODE_NOT_IN_PAGE_FLAGS
1579 : extern int page_to_nid(const struct page *page);
1580 : #else
1581 : static inline int page_to_nid(const struct page *page)
1582 : {
1583 149084 : struct page *p = (struct page *)page;
1584 :
1585 : return (PF_POISONED_CHECK(p)->flags >> NODES_PGSHIFT) & NODES_MASK;
1586 : }
1587 : #endif
1588 :
1589 : static inline int folio_nid(const struct folio *folio)
1590 : {
1591 7584 : return page_to_nid(&folio->page);
1592 : }
1593 :
1594 : #ifdef CONFIG_NUMA_BALANCING
1595 : /* page access time bits needs to hold at least 4 seconds */
1596 : #define PAGE_ACCESS_TIME_MIN_BITS 12
1597 : #if LAST_CPUPID_SHIFT < PAGE_ACCESS_TIME_MIN_BITS
1598 : #define PAGE_ACCESS_TIME_BUCKETS \
1599 : (PAGE_ACCESS_TIME_MIN_BITS - LAST_CPUPID_SHIFT)
1600 : #else
1601 : #define PAGE_ACCESS_TIME_BUCKETS 0
1602 : #endif
1603 :
1604 : #define PAGE_ACCESS_TIME_MASK \
1605 : (LAST_CPUPID_MASK << PAGE_ACCESS_TIME_BUCKETS)
1606 :
1607 : static inline int cpu_pid_to_cpupid(int cpu, int pid)
1608 : {
1609 : return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK);
1610 : }
1611 :
1612 : static inline int cpupid_to_pid(int cpupid)
1613 : {
1614 : return cpupid & LAST__PID_MASK;
1615 : }
1616 :
1617 : static inline int cpupid_to_cpu(int cpupid)
1618 : {
1619 : return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK;
1620 : }
1621 :
1622 : static inline int cpupid_to_nid(int cpupid)
1623 : {
1624 : return cpu_to_node(cpupid_to_cpu(cpupid));
1625 : }
1626 :
1627 : static inline bool cpupid_pid_unset(int cpupid)
1628 : {
1629 : return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK);
1630 : }
1631 :
1632 : static inline bool cpupid_cpu_unset(int cpupid)
1633 : {
1634 : return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK);
1635 : }
1636 :
1637 : static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid)
1638 : {
1639 : return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid);
1640 : }
1641 :
1642 : #define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid)
1643 : #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
1644 : static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1645 : {
1646 : return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK);
1647 : }
1648 :
1649 : static inline int page_cpupid_last(struct page *page)
1650 : {
1651 : return page->_last_cpupid;
1652 : }
1653 : static inline void page_cpupid_reset_last(struct page *page)
1654 : {
1655 : page->_last_cpupid = -1 & LAST_CPUPID_MASK;
1656 : }
1657 : #else
1658 : static inline int page_cpupid_last(struct page *page)
1659 : {
1660 : return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
1661 : }
1662 :
1663 : extern int page_cpupid_xchg_last(struct page *page, int cpupid);
1664 :
1665 : static inline void page_cpupid_reset_last(struct page *page)
1666 : {
1667 : page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT;
1668 : }
1669 : #endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
1670 :
1671 : static inline int xchg_page_access_time(struct page *page, int time)
1672 : {
1673 : int last_time;
1674 :
1675 : last_time = page_cpupid_xchg_last(page, time >> PAGE_ACCESS_TIME_BUCKETS);
1676 : return last_time << PAGE_ACCESS_TIME_BUCKETS;
1677 : }
1678 :
1679 : static inline void vma_set_access_pid_bit(struct vm_area_struct *vma)
1680 : {
1681 : unsigned int pid_bit;
1682 :
1683 : pid_bit = hash_32(current->pid, ilog2(BITS_PER_LONG));
1684 : if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->access_pids[1])) {
1685 : __set_bit(pid_bit, &vma->numab_state->access_pids[1]);
1686 : }
1687 : }
1688 : #else /* !CONFIG_NUMA_BALANCING */
1689 : static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1690 : {
1691 0 : return page_to_nid(page); /* XXX */
1692 : }
1693 :
1694 : static inline int xchg_page_access_time(struct page *page, int time)
1695 : {
1696 : return 0;
1697 : }
1698 :
1699 : static inline int page_cpupid_last(struct page *page)
1700 : {
1701 : return page_to_nid(page); /* XXX */
1702 : }
1703 :
1704 : static inline int cpupid_to_nid(int cpupid)
1705 : {
1706 : return -1;
1707 : }
1708 :
1709 : static inline int cpupid_to_pid(int cpupid)
1710 : {
1711 : return -1;
1712 : }
1713 :
1714 : static inline int cpupid_to_cpu(int cpupid)
1715 : {
1716 : return -1;
1717 : }
1718 :
1719 : static inline int cpu_pid_to_cpupid(int nid, int pid)
1720 : {
1721 : return -1;
1722 : }
1723 :
1724 : static inline bool cpupid_pid_unset(int cpupid)
1725 : {
1726 : return true;
1727 : }
1728 :
1729 : static inline void page_cpupid_reset_last(struct page *page)
1730 : {
1731 : }
1732 :
1733 : static inline bool cpupid_match_pid(struct task_struct *task, int cpupid)
1734 : {
1735 : return false;
1736 : }
1737 :
1738 : static inline void vma_set_access_pid_bit(struct vm_area_struct *vma)
1739 : {
1740 : }
1741 : #endif /* CONFIG_NUMA_BALANCING */
1742 :
1743 : #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
1744 :
1745 : /*
1746 : * KASAN per-page tags are stored xor'ed with 0xff. This allows to avoid
1747 : * setting tags for all pages to native kernel tag value 0xff, as the default
1748 : * value 0x00 maps to 0xff.
1749 : */
1750 :
1751 : static inline u8 page_kasan_tag(const struct page *page)
1752 : {
1753 : u8 tag = 0xff;
1754 :
1755 : if (kasan_enabled()) {
1756 : tag = (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK;
1757 : tag ^= 0xff;
1758 : }
1759 :
1760 : return tag;
1761 : }
1762 :
1763 : static inline void page_kasan_tag_set(struct page *page, u8 tag)
1764 : {
1765 : unsigned long old_flags, flags;
1766 :
1767 : if (!kasan_enabled())
1768 : return;
1769 :
1770 : tag ^= 0xff;
1771 : old_flags = READ_ONCE(page->flags);
1772 : do {
1773 : flags = old_flags;
1774 : flags &= ~(KASAN_TAG_MASK << KASAN_TAG_PGSHIFT);
1775 : flags |= (tag & KASAN_TAG_MASK) << KASAN_TAG_PGSHIFT;
1776 : } while (unlikely(!try_cmpxchg(&page->flags, &old_flags, flags)));
1777 : }
1778 :
1779 : static inline void page_kasan_tag_reset(struct page *page)
1780 : {
1781 : if (kasan_enabled())
1782 : page_kasan_tag_set(page, 0xff);
1783 : }
1784 :
1785 : #else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
1786 :
1787 : static inline u8 page_kasan_tag(const struct page *page)
1788 : {
1789 : return 0xff;
1790 : }
1791 :
1792 : static inline void page_kasan_tag_set(struct page *page, u8 tag) { }
1793 : static inline void page_kasan_tag_reset(struct page *page) { }
1794 :
1795 : #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
1796 :
1797 : static inline struct zone *page_zone(const struct page *page)
1798 : {
1799 313844 : return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
1800 : }
1801 :
1802 : static inline pg_data_t *page_pgdat(const struct page *page)
1803 : {
1804 6956 : return NODE_DATA(page_to_nid(page));
1805 : }
1806 :
1807 : static inline struct zone *folio_zone(const struct folio *folio)
1808 : {
1809 0 : return page_zone(&folio->page);
1810 : }
1811 :
1812 : static inline pg_data_t *folio_pgdat(const struct folio *folio)
1813 : {
1814 3947 : return page_pgdat(&folio->page);
1815 : }
1816 :
1817 : #ifdef SECTION_IN_PAGE_FLAGS
1818 : static inline void set_page_section(struct page *page, unsigned long section)
1819 : {
1820 : page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
1821 : page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
1822 : }
1823 :
1824 : static inline unsigned long page_to_section(const struct page *page)
1825 : {
1826 : return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
1827 : }
1828 : #endif
1829 :
1830 : /**
1831 : * folio_pfn - Return the Page Frame Number of a folio.
1832 : * @folio: The folio.
1833 : *
1834 : * A folio may contain multiple pages. The pages have consecutive
1835 : * Page Frame Numbers.
1836 : *
1837 : * Return: The Page Frame Number of the first page in the folio.
1838 : */
1839 : static inline unsigned long folio_pfn(struct folio *folio)
1840 : {
1841 0 : return page_to_pfn(&folio->page);
1842 : }
1843 :
1844 : static inline struct folio *pfn_folio(unsigned long pfn)
1845 : {
1846 : return page_folio(pfn_to_page(pfn));
1847 : }
1848 :
1849 : /**
1850 : * folio_maybe_dma_pinned - Report if a folio may be pinned for DMA.
1851 : * @folio: The folio.
1852 : *
1853 : * This function checks if a folio has been pinned via a call to
1854 : * a function in the pin_user_pages() family.
1855 : *
1856 : * For small folios, the return value is partially fuzzy: false is not fuzzy,
1857 : * because it means "definitely not pinned for DMA", but true means "probably
1858 : * pinned for DMA, but possibly a false positive due to having at least
1859 : * GUP_PIN_COUNTING_BIAS worth of normal folio references".
1860 : *
1861 : * False positives are OK, because: a) it's unlikely for a folio to
1862 : * get that many refcounts, and b) all the callers of this routine are
1863 : * expected to be able to deal gracefully with a false positive.
1864 : *
1865 : * For large folios, the result will be exactly correct. That's because
1866 : * we have more tracking data available: the _pincount field is used
1867 : * instead of the GUP_PIN_COUNTING_BIAS scheme.
1868 : *
1869 : * For more information, please see Documentation/core-api/pin_user_pages.rst.
1870 : *
1871 : * Return: True, if it is likely that the page has been "dma-pinned".
1872 : * False, if the page is definitely not dma-pinned.
1873 : */
1874 : static inline bool folio_maybe_dma_pinned(struct folio *folio)
1875 : {
1876 0 : if (folio_test_large(folio))
1877 0 : return atomic_read(&folio->_pincount) > 0;
1878 :
1879 : /*
1880 : * folio_ref_count() is signed. If that refcount overflows, then
1881 : * folio_ref_count() returns a negative value, and callers will avoid
1882 : * further incrementing the refcount.
1883 : *
1884 : * Here, for that overflow case, use the sign bit to count a little
1885 : * bit higher via unsigned math, and thus still get an accurate result.
1886 : */
1887 0 : return ((unsigned int)folio_ref_count(folio)) >=
1888 : GUP_PIN_COUNTING_BIAS;
1889 : }
1890 :
1891 : static inline bool page_maybe_dma_pinned(struct page *page)
1892 : {
1893 0 : return folio_maybe_dma_pinned(page_folio(page));
1894 : }
1895 :
1896 : /*
1897 : * This should most likely only be called during fork() to see whether we
1898 : * should break the cow immediately for an anon page on the src mm.
1899 : *
1900 : * The caller has to hold the PT lock and the vma->vm_mm->->write_protect_seq.
1901 : */
1902 0 : static inline bool page_needs_cow_for_dma(struct vm_area_struct *vma,
1903 : struct page *page)
1904 : {
1905 : VM_BUG_ON(!(raw_read_seqcount(&vma->vm_mm->write_protect_seq) & 1));
1906 :
1907 0 : if (!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))
1908 : return false;
1909 :
1910 : return page_maybe_dma_pinned(page);
1911 : }
1912 :
1913 : /* MIGRATE_CMA and ZONE_MOVABLE do not allow pin pages */
1914 : #ifdef CONFIG_MIGRATION
1915 : static inline bool is_longterm_pinnable_page(struct page *page)
1916 : {
1917 : #ifdef CONFIG_CMA
1918 : int mt = get_pageblock_migratetype(page);
1919 :
1920 : if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE)
1921 : return false;
1922 : #endif
1923 : /* The zero page may always be pinned */
1924 0 : if (is_zero_pfn(page_to_pfn(page)))
1925 : return true;
1926 :
1927 : /* Coherent device memory must always allow eviction. */
1928 0 : if (is_device_coherent_page(page))
1929 : return false;
1930 :
1931 : /* Otherwise, non-movable zone pages can be pinned. */
1932 0 : return !is_zone_movable_page(page);
1933 : }
1934 : #else
1935 : static inline bool is_longterm_pinnable_page(struct page *page)
1936 : {
1937 : return true;
1938 : }
1939 : #endif
1940 :
1941 : static inline bool folio_is_longterm_pinnable(struct folio *folio)
1942 : {
1943 0 : return is_longterm_pinnable_page(&folio->page);
1944 : }
1945 :
1946 : static inline void set_page_zone(struct page *page, enum zone_type zone)
1947 : {
1948 : page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
1949 265940 : page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
1950 : }
1951 :
1952 : static inline void set_page_node(struct page *page, unsigned long node)
1953 : {
1954 : page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
1955 : page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
1956 : }
1957 :
1958 : static inline void set_page_links(struct page *page, enum zone_type zone,
1959 : unsigned long node, unsigned long pfn)
1960 : {
1961 531880 : set_page_zone(page, zone);
1962 265940 : set_page_node(page, node);
1963 : #ifdef SECTION_IN_PAGE_FLAGS
1964 : set_page_section(page, pfn_to_section_nr(pfn));
1965 : #endif
1966 : }
1967 :
1968 : /**
1969 : * folio_nr_pages - The number of pages in the folio.
1970 : * @folio: The folio.
1971 : *
1972 : * Return: A positive power of two.
1973 : */
1974 : static inline long folio_nr_pages(struct folio *folio)
1975 : {
1976 0 : if (!folio_test_large(folio))
1977 : return 1;
1978 : #ifdef CONFIG_64BIT
1979 0 : return folio->_folio_nr_pages;
1980 : #else
1981 : return 1L << folio->_folio_order;
1982 : #endif
1983 : }
1984 :
1985 : /*
1986 : * compound_nr() returns the number of pages in this potentially compound
1987 : * page. compound_nr() can be called on a tail page, and is defined to
1988 : * return 1 in that case.
1989 : */
1990 : static inline unsigned long compound_nr(struct page *page)
1991 : {
1992 0 : struct folio *folio = (struct folio *)page;
1993 :
1994 0 : if (!test_bit(PG_head, &folio->flags))
1995 : return 1;
1996 : #ifdef CONFIG_64BIT
1997 0 : return folio->_folio_nr_pages;
1998 : #else
1999 : return 1L << folio->_folio_order;
2000 : #endif
2001 : }
2002 :
2003 : /**
2004 : * thp_nr_pages - The number of regular pages in this huge page.
2005 : * @page: The head page of a huge page.
2006 : */
2007 : static inline int thp_nr_pages(struct page *page)
2008 : {
2009 0 : return folio_nr_pages((struct folio *)page);
2010 : }
2011 :
2012 : /**
2013 : * folio_next - Move to the next physical folio.
2014 : * @folio: The folio we're currently operating on.
2015 : *
2016 : * If you have physically contiguous memory which may span more than
2017 : * one folio (eg a &struct bio_vec), use this function to move from one
2018 : * folio to the next. Do not use it if the memory is only virtually
2019 : * contiguous as the folios are almost certainly not adjacent to each
2020 : * other. This is the folio equivalent to writing ``page++``.
2021 : *
2022 : * Context: We assume that the folios are refcounted and/or locked at a
2023 : * higher level and do not adjust the reference counts.
2024 : * Return: The next struct folio.
2025 : */
2026 : static inline struct folio *folio_next(struct folio *folio)
2027 : {
2028 0 : return (struct folio *)folio_page(folio, folio_nr_pages(folio));
2029 : }
2030 :
2031 : /**
2032 : * folio_shift - The size of the memory described by this folio.
2033 : * @folio: The folio.
2034 : *
2035 : * A folio represents a number of bytes which is a power-of-two in size.
2036 : * This function tells you which power-of-two the folio is. See also
2037 : * folio_size() and folio_order().
2038 : *
2039 : * Context: The caller should have a reference on the folio to prevent
2040 : * it from being split. It is not necessary for the folio to be locked.
2041 : * Return: The base-2 logarithm of the size of this folio.
2042 : */
2043 : static inline unsigned int folio_shift(struct folio *folio)
2044 : {
2045 0 : return PAGE_SHIFT + folio_order(folio);
2046 : }
2047 :
2048 : /**
2049 : * folio_size - The number of bytes in a folio.
2050 : * @folio: The folio.
2051 : *
2052 : * Context: The caller should have a reference on the folio to prevent
2053 : * it from being split. It is not necessary for the folio to be locked.
2054 : * Return: The number of bytes in this folio.
2055 : */
2056 : static inline size_t folio_size(struct folio *folio)
2057 : {
2058 0 : return PAGE_SIZE << folio_order(folio);
2059 : }
2060 :
2061 : /**
2062 : * folio_estimated_sharers - Estimate the number of sharers of a folio.
2063 : * @folio: The folio.
2064 : *
2065 : * folio_estimated_sharers() aims to serve as a function to efficiently
2066 : * estimate the number of processes sharing a folio. This is done by
2067 : * looking at the precise mapcount of the first subpage in the folio, and
2068 : * assuming the other subpages are the same. This may not be true for large
2069 : * folios. If you want exact mapcounts for exact calculations, look at
2070 : * page_mapcount() or folio_total_mapcount().
2071 : *
2072 : * Return: The estimated number of processes sharing a folio.
2073 : */
2074 : static inline int folio_estimated_sharers(struct folio *folio)
2075 : {
2076 : return page_mapcount(folio_page(folio, 0));
2077 : }
2078 :
2079 : #ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE
2080 : static inline int arch_make_page_accessible(struct page *page)
2081 : {
2082 : return 0;
2083 : }
2084 : #endif
2085 :
2086 : #ifndef HAVE_ARCH_MAKE_FOLIO_ACCESSIBLE
2087 : static inline int arch_make_folio_accessible(struct folio *folio)
2088 : {
2089 : int ret;
2090 0 : long i, nr = folio_nr_pages(folio);
2091 :
2092 0 : for (i = 0; i < nr; i++) {
2093 : ret = arch_make_page_accessible(folio_page(folio, i));
2094 : if (ret)
2095 : break;
2096 : }
2097 :
2098 : return ret;
2099 : }
2100 : #endif
2101 :
2102 : /*
2103 : * Some inline functions in vmstat.h depend on page_zone()
2104 : */
2105 : #include <linux/vmstat.h>
2106 :
2107 : static __always_inline void *lowmem_page_address(const struct page *page)
2108 : {
2109 81026 : return page_to_virt(page);
2110 : }
2111 :
2112 : #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
2113 : #define HASHED_PAGE_VIRTUAL
2114 : #endif
2115 :
2116 : #if defined(WANT_PAGE_VIRTUAL)
2117 : static inline void *page_address(const struct page *page)
2118 : {
2119 : return page->virtual;
2120 : }
2121 : static inline void set_page_address(struct page *page, void *address)
2122 : {
2123 : page->virtual = address;
2124 : }
2125 : #define page_address_init() do { } while(0)
2126 : #endif
2127 :
2128 : #if defined(HASHED_PAGE_VIRTUAL)
2129 : void *page_address(const struct page *page);
2130 : void set_page_address(struct page *page, void *virtual);
2131 : void page_address_init(void);
2132 : #endif
2133 :
2134 : #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
2135 : #define page_address(page) lowmem_page_address(page)
2136 : #define set_page_address(page, address) do { } while(0)
2137 : #define page_address_init() do { } while(0)
2138 : #endif
2139 :
2140 : static inline void *folio_address(const struct folio *folio)
2141 : {
2142 4388 : return page_address(&folio->page);
2143 : }
2144 :
2145 : extern void *page_rmapping(struct page *page);
2146 : extern pgoff_t __page_file_index(struct page *page);
2147 :
2148 : /*
2149 : * Return the pagecache index of the passed page. Regular pagecache pages
2150 : * use ->index whereas swapcache pages use swp_offset(->private)
2151 : */
2152 0 : static inline pgoff_t page_index(struct page *page)
2153 : {
2154 0 : if (unlikely(PageSwapCache(page)))
2155 0 : return __page_file_index(page);
2156 0 : return page->index;
2157 : }
2158 :
2159 : /*
2160 : * Return true only if the page has been allocated with
2161 : * ALLOC_NO_WATERMARKS and the low watermark was not
2162 : * met implying that the system is under some pressure.
2163 : */
2164 : static inline bool page_is_pfmemalloc(const struct page *page)
2165 : {
2166 : /*
2167 : * lru.next has bit 1 set if the page is allocated from the
2168 : * pfmemalloc reserves. Callers may simply overwrite it if
2169 : * they do not need to preserve that information.
2170 : */
2171 0 : return (uintptr_t)page->lru.next & BIT(1);
2172 : }
2173 :
2174 : /*
2175 : * Return true only if the folio has been allocated with
2176 : * ALLOC_NO_WATERMARKS and the low watermark was not
2177 : * met implying that the system is under some pressure.
2178 : */
2179 : static inline bool folio_is_pfmemalloc(const struct folio *folio)
2180 : {
2181 : /*
2182 : * lru.next has bit 1 set if the page is allocated from the
2183 : * pfmemalloc reserves. Callers may simply overwrite it if
2184 : * they do not need to preserve that information.
2185 : */
2186 2194 : return (uintptr_t)folio->lru.next & BIT(1);
2187 : }
2188 :
2189 : /*
2190 : * Only to be called by the page allocator on a freshly allocated
2191 : * page.
2192 : */
2193 : static inline void set_page_pfmemalloc(struct page *page)
2194 : {
2195 0 : page->lru.next = (void *)BIT(1);
2196 : }
2197 :
2198 : static inline void clear_page_pfmemalloc(struct page *page)
2199 : {
2200 44763 : page->lru.next = NULL;
2201 : }
2202 :
2203 : /*
2204 : * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
2205 : */
2206 : extern void pagefault_out_of_memory(void);
2207 :
2208 : #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
2209 : #define offset_in_thp(page, p) ((unsigned long)(p) & (thp_size(page) - 1))
2210 : #define offset_in_folio(folio, p) ((unsigned long)(p) & (folio_size(folio) - 1))
2211 :
2212 : /*
2213 : * Flags passed to show_mem() and show_free_areas() to suppress output in
2214 : * various contexts.
2215 : */
2216 : #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */
2217 :
2218 : extern void __show_free_areas(unsigned int flags, nodemask_t *nodemask, int max_zone_idx);
2219 : static void __maybe_unused show_free_areas(unsigned int flags, nodemask_t *nodemask)
2220 : {
2221 : __show_free_areas(flags, nodemask, MAX_NR_ZONES - 1);
2222 : }
2223 :
2224 : /*
2225 : * Parameter block passed down to zap_pte_range in exceptional cases.
2226 : */
2227 : struct zap_details {
2228 : struct folio *single_folio; /* Locked folio to be unmapped */
2229 : bool even_cows; /* Zap COWed private pages too? */
2230 : zap_flags_t zap_flags; /* Extra flags for zapping */
2231 : };
2232 :
2233 : /*
2234 : * Whether to drop the pte markers, for example, the uffd-wp information for
2235 : * file-backed memory. This should only be specified when we will completely
2236 : * drop the page in the mm, either by truncation or unmapping of the vma. By
2237 : * default, the flag is not set.
2238 : */
2239 : #define ZAP_FLAG_DROP_MARKER ((__force zap_flags_t) BIT(0))
2240 : /* Set in unmap_vmas() to indicate a final unmap call. Only used by hugetlb */
2241 : #define ZAP_FLAG_UNMAP ((__force zap_flags_t) BIT(1))
2242 :
2243 : #ifdef CONFIG_SCHED_MM_CID
2244 : void sched_mm_cid_before_execve(struct task_struct *t);
2245 : void sched_mm_cid_after_execve(struct task_struct *t);
2246 : void sched_mm_cid_fork(struct task_struct *t);
2247 : void sched_mm_cid_exit_signals(struct task_struct *t);
2248 : static inline int task_mm_cid(struct task_struct *t)
2249 : {
2250 : return t->mm_cid;
2251 : }
2252 : #else
2253 : static inline void sched_mm_cid_before_execve(struct task_struct *t) { }
2254 : static inline void sched_mm_cid_after_execve(struct task_struct *t) { }
2255 : static inline void sched_mm_cid_fork(struct task_struct *t) { }
2256 : static inline void sched_mm_cid_exit_signals(struct task_struct *t) { }
2257 : static inline int task_mm_cid(struct task_struct *t)
2258 : {
2259 : /*
2260 : * Use the processor id as a fall-back when the mm cid feature is
2261 : * disabled. This provides functional per-cpu data structure accesses
2262 : * in user-space, althrough it won't provide the memory usage benefits.
2263 : */
2264 : return raw_smp_processor_id();
2265 : }
2266 : #endif
2267 :
2268 : #ifdef CONFIG_MMU
2269 : extern bool can_do_mlock(void);
2270 : #else
2271 : static inline bool can_do_mlock(void) { return false; }
2272 : #endif
2273 : extern int user_shm_lock(size_t, struct ucounts *);
2274 : extern void user_shm_unlock(size_t, struct ucounts *);
2275 :
2276 : struct folio *vm_normal_folio(struct vm_area_struct *vma, unsigned long addr,
2277 : pte_t pte);
2278 : struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
2279 : pte_t pte);
2280 : struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
2281 : pmd_t pmd);
2282 :
2283 : void zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
2284 : unsigned long size);
2285 : void zap_page_range_single(struct vm_area_struct *vma, unsigned long address,
2286 : unsigned long size, struct zap_details *details);
2287 : static inline void zap_vma_pages(struct vm_area_struct *vma)
2288 : {
2289 : zap_page_range_single(vma, vma->vm_start,
2290 : vma->vm_end - vma->vm_start, NULL);
2291 : }
2292 : void unmap_vmas(struct mmu_gather *tlb, struct maple_tree *mt,
2293 : struct vm_area_struct *start_vma, unsigned long start,
2294 : unsigned long end, bool mm_wr_locked);
2295 :
2296 : struct mmu_notifier_range;
2297 :
2298 : void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
2299 : unsigned long end, unsigned long floor, unsigned long ceiling);
2300 : int
2301 : copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma);
2302 : int follow_pte(struct mm_struct *mm, unsigned long address,
2303 : pte_t **ptepp, spinlock_t **ptlp);
2304 : int follow_pfn(struct vm_area_struct *vma, unsigned long address,
2305 : unsigned long *pfn);
2306 : int follow_phys(struct vm_area_struct *vma, unsigned long address,
2307 : unsigned int flags, unsigned long *prot, resource_size_t *phys);
2308 : int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
2309 : void *buf, int len, int write);
2310 :
2311 : extern void truncate_pagecache(struct inode *inode, loff_t new);
2312 : extern void truncate_setsize(struct inode *inode, loff_t newsize);
2313 : void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
2314 : void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
2315 : int generic_error_remove_page(struct address_space *mapping, struct page *page);
2316 :
2317 : #ifdef CONFIG_MMU
2318 : extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
2319 : unsigned long address, unsigned int flags,
2320 : struct pt_regs *regs);
2321 : extern int fixup_user_fault(struct mm_struct *mm,
2322 : unsigned long address, unsigned int fault_flags,
2323 : bool *unlocked);
2324 : void unmap_mapping_pages(struct address_space *mapping,
2325 : pgoff_t start, pgoff_t nr, bool even_cows);
2326 : void unmap_mapping_range(struct address_space *mapping,
2327 : loff_t const holebegin, loff_t const holelen, int even_cows);
2328 : #else
2329 : static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
2330 : unsigned long address, unsigned int flags,
2331 : struct pt_regs *regs)
2332 : {
2333 : /* should never happen if there's no MMU */
2334 : BUG();
2335 : return VM_FAULT_SIGBUS;
2336 : }
2337 : static inline int fixup_user_fault(struct mm_struct *mm, unsigned long address,
2338 : unsigned int fault_flags, bool *unlocked)
2339 : {
2340 : /* should never happen if there's no MMU */
2341 : BUG();
2342 : return -EFAULT;
2343 : }
2344 : static inline void unmap_mapping_pages(struct address_space *mapping,
2345 : pgoff_t start, pgoff_t nr, bool even_cows) { }
2346 : static inline void unmap_mapping_range(struct address_space *mapping,
2347 : loff_t const holebegin, loff_t const holelen, int even_cows) { }
2348 : #endif
2349 :
2350 : static inline void unmap_shared_mapping_range(struct address_space *mapping,
2351 : loff_t const holebegin, loff_t const holelen)
2352 : {
2353 : unmap_mapping_range(mapping, holebegin, holelen, 0);
2354 : }
2355 :
2356 : extern int access_process_vm(struct task_struct *tsk, unsigned long addr,
2357 : void *buf, int len, unsigned int gup_flags);
2358 : extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
2359 : void *buf, int len, unsigned int gup_flags);
2360 : extern int __access_remote_vm(struct mm_struct *mm, unsigned long addr,
2361 : void *buf, int len, unsigned int gup_flags);
2362 :
2363 : long get_user_pages_remote(struct mm_struct *mm,
2364 : unsigned long start, unsigned long nr_pages,
2365 : unsigned int gup_flags, struct page **pages,
2366 : struct vm_area_struct **vmas, int *locked);
2367 : long pin_user_pages_remote(struct mm_struct *mm,
2368 : unsigned long start, unsigned long nr_pages,
2369 : unsigned int gup_flags, struct page **pages,
2370 : struct vm_area_struct **vmas, int *locked);
2371 : long get_user_pages(unsigned long start, unsigned long nr_pages,
2372 : unsigned int gup_flags, struct page **pages,
2373 : struct vm_area_struct **vmas);
2374 : long pin_user_pages(unsigned long start, unsigned long nr_pages,
2375 : unsigned int gup_flags, struct page **pages,
2376 : struct vm_area_struct **vmas);
2377 : long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
2378 : struct page **pages, unsigned int gup_flags);
2379 : long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
2380 : struct page **pages, unsigned int gup_flags);
2381 :
2382 : int get_user_pages_fast(unsigned long start, int nr_pages,
2383 : unsigned int gup_flags, struct page **pages);
2384 : int pin_user_pages_fast(unsigned long start, int nr_pages,
2385 : unsigned int gup_flags, struct page **pages);
2386 :
2387 : int account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc);
2388 : int __account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc,
2389 : struct task_struct *task, bool bypass_rlim);
2390 :
2391 : struct kvec;
2392 : struct page *get_dump_page(unsigned long addr);
2393 :
2394 : bool folio_mark_dirty(struct folio *folio);
2395 : bool set_page_dirty(struct page *page);
2396 : int set_page_dirty_lock(struct page *page);
2397 :
2398 : int get_cmdline(struct task_struct *task, char *buffer, int buflen);
2399 :
2400 : extern unsigned long move_page_tables(struct vm_area_struct *vma,
2401 : unsigned long old_addr, struct vm_area_struct *new_vma,
2402 : unsigned long new_addr, unsigned long len,
2403 : bool need_rmap_locks);
2404 :
2405 : /*
2406 : * Flags used by change_protection(). For now we make it a bitmap so
2407 : * that we can pass in multiple flags just like parameters. However
2408 : * for now all the callers are only use one of the flags at the same
2409 : * time.
2410 : */
2411 : /*
2412 : * Whether we should manually check if we can map individual PTEs writable,
2413 : * because something (e.g., COW, uffd-wp) blocks that from happening for all
2414 : * PTEs automatically in a writable mapping.
2415 : */
2416 : #define MM_CP_TRY_CHANGE_WRITABLE (1UL << 0)
2417 : /* Whether this protection change is for NUMA hints */
2418 : #define MM_CP_PROT_NUMA (1UL << 1)
2419 : /* Whether this change is for write protecting */
2420 : #define MM_CP_UFFD_WP (1UL << 2) /* do wp */
2421 : #define MM_CP_UFFD_WP_RESOLVE (1UL << 3) /* Resolve wp */
2422 : #define MM_CP_UFFD_WP_ALL (MM_CP_UFFD_WP | \
2423 : MM_CP_UFFD_WP_RESOLVE)
2424 :
2425 : int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot);
2426 0 : static inline bool vma_wants_manual_pte_write_upgrade(struct vm_area_struct *vma)
2427 : {
2428 : /*
2429 : * We want to check manually if we can change individual PTEs writable
2430 : * if we can't do that automatically for all PTEs in a mapping. For
2431 : * private mappings, that's always the case when we have write
2432 : * permissions as we properly have to handle COW.
2433 : */
2434 0 : if (vma->vm_flags & VM_SHARED)
2435 0 : return vma_wants_writenotify(vma, vma->vm_page_prot);
2436 0 : return !!(vma->vm_flags & VM_WRITE);
2437 :
2438 : }
2439 : bool can_change_pte_writable(struct vm_area_struct *vma, unsigned long addr,
2440 : pte_t pte);
2441 : extern long change_protection(struct mmu_gather *tlb,
2442 : struct vm_area_struct *vma, unsigned long start,
2443 : unsigned long end, unsigned long cp_flags);
2444 : extern int mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb,
2445 : struct vm_area_struct *vma, struct vm_area_struct **pprev,
2446 : unsigned long start, unsigned long end, unsigned long newflags);
2447 :
2448 : /*
2449 : * doesn't attempt to fault and will return short.
2450 : */
2451 : int get_user_pages_fast_only(unsigned long start, int nr_pages,
2452 : unsigned int gup_flags, struct page **pages);
2453 :
2454 : static inline bool get_user_page_fast_only(unsigned long addr,
2455 : unsigned int gup_flags, struct page **pagep)
2456 : {
2457 : return get_user_pages_fast_only(addr, 1, gup_flags, pagep) == 1;
2458 : }
2459 : /*
2460 : * per-process(per-mm_struct) statistics.
2461 : */
2462 : static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
2463 : {
2464 0 : return percpu_counter_read_positive(&mm->rss_stat[member]);
2465 : }
2466 :
2467 : void mm_trace_rss_stat(struct mm_struct *mm, int member);
2468 :
2469 0 : static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
2470 : {
2471 0 : percpu_counter_add(&mm->rss_stat[member], value);
2472 :
2473 0 : mm_trace_rss_stat(mm, member);
2474 0 : }
2475 :
2476 : static inline void inc_mm_counter(struct mm_struct *mm, int member)
2477 : {
2478 0 : percpu_counter_inc(&mm->rss_stat[member]);
2479 :
2480 0 : mm_trace_rss_stat(mm, member);
2481 : }
2482 :
2483 : static inline void dec_mm_counter(struct mm_struct *mm, int member)
2484 : {
2485 0 : percpu_counter_dec(&mm->rss_stat[member]);
2486 :
2487 0 : mm_trace_rss_stat(mm, member);
2488 : }
2489 :
2490 : /* Optimized variant when page is already known not to be PageAnon */
2491 : static inline int mm_counter_file(struct page *page)
2492 : {
2493 0 : if (PageSwapBacked(page))
2494 : return MM_SHMEMPAGES;
2495 : return MM_FILEPAGES;
2496 : }
2497 :
2498 0 : static inline int mm_counter(struct page *page)
2499 : {
2500 0 : if (PageAnon(page))
2501 : return MM_ANONPAGES;
2502 : return mm_counter_file(page);
2503 : }
2504 :
2505 : static inline unsigned long get_mm_rss(struct mm_struct *mm)
2506 : {
2507 0 : return get_mm_counter(mm, MM_FILEPAGES) +
2508 0 : get_mm_counter(mm, MM_ANONPAGES) +
2509 0 : get_mm_counter(mm, MM_SHMEMPAGES);
2510 : }
2511 :
2512 : static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
2513 : {
2514 0 : return max(mm->hiwater_rss, get_mm_rss(mm));
2515 : }
2516 :
2517 : static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
2518 : {
2519 : return max(mm->hiwater_vm, mm->total_vm);
2520 : }
2521 :
2522 : static inline void update_hiwater_rss(struct mm_struct *mm)
2523 : {
2524 0 : unsigned long _rss = get_mm_rss(mm);
2525 :
2526 0 : if ((mm)->hiwater_rss < _rss)
2527 0 : (mm)->hiwater_rss = _rss;
2528 : }
2529 :
2530 : static inline void update_hiwater_vm(struct mm_struct *mm)
2531 : {
2532 0 : if (mm->hiwater_vm < mm->total_vm)
2533 0 : mm->hiwater_vm = mm->total_vm;
2534 : }
2535 :
2536 : static inline void reset_mm_hiwater_rss(struct mm_struct *mm)
2537 : {
2538 0 : mm->hiwater_rss = get_mm_rss(mm);
2539 : }
2540 :
2541 : static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
2542 : struct mm_struct *mm)
2543 : {
2544 0 : unsigned long hiwater_rss = get_mm_hiwater_rss(mm);
2545 :
2546 0 : if (*maxrss < hiwater_rss)
2547 0 : *maxrss = hiwater_rss;
2548 : }
2549 :
2550 : #if defined(SPLIT_RSS_COUNTING)
2551 : void sync_mm_rss(struct mm_struct *mm);
2552 : #else
2553 : static inline void sync_mm_rss(struct mm_struct *mm)
2554 : {
2555 : }
2556 : #endif
2557 :
2558 : #ifndef CONFIG_ARCH_HAS_PTE_SPECIAL
2559 : static inline int pte_special(pte_t pte)
2560 : {
2561 : return 0;
2562 : }
2563 :
2564 : static inline pte_t pte_mkspecial(pte_t pte)
2565 : {
2566 : return pte;
2567 : }
2568 : #endif
2569 :
2570 : #ifndef CONFIG_ARCH_HAS_PTE_DEVMAP
2571 : static inline int pte_devmap(pte_t pte)
2572 : {
2573 : return 0;
2574 : }
2575 : #endif
2576 :
2577 : extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
2578 : spinlock_t **ptl);
2579 : static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
2580 : spinlock_t **ptl)
2581 : {
2582 : pte_t *ptep;
2583 0 : __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl));
2584 : return ptep;
2585 : }
2586 :
2587 : #ifdef __PAGETABLE_P4D_FOLDED
2588 : static inline int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
2589 : unsigned long address)
2590 : {
2591 : return 0;
2592 : }
2593 : #else
2594 : int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
2595 : #endif
2596 :
2597 : #if defined(__PAGETABLE_PUD_FOLDED) || !defined(CONFIG_MMU)
2598 : static inline int __pud_alloc(struct mm_struct *mm, p4d_t *p4d,
2599 : unsigned long address)
2600 : {
2601 : return 0;
2602 : }
2603 : static inline void mm_inc_nr_puds(struct mm_struct *mm) {}
2604 : static inline void mm_dec_nr_puds(struct mm_struct *mm) {}
2605 :
2606 : #else
2607 : int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address);
2608 :
2609 : static inline void mm_inc_nr_puds(struct mm_struct *mm)
2610 : {
2611 : if (mm_pud_folded(mm))
2612 : return;
2613 : atomic_long_add(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
2614 : }
2615 :
2616 : static inline void mm_dec_nr_puds(struct mm_struct *mm)
2617 : {
2618 : if (mm_pud_folded(mm))
2619 : return;
2620 : atomic_long_sub(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
2621 : }
2622 : #endif
2623 :
2624 : #if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU)
2625 : static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
2626 : unsigned long address)
2627 : {
2628 : return 0;
2629 : }
2630 :
2631 : static inline void mm_inc_nr_pmds(struct mm_struct *mm) {}
2632 : static inline void mm_dec_nr_pmds(struct mm_struct *mm) {}
2633 :
2634 : #else
2635 : int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
2636 :
2637 : static inline void mm_inc_nr_pmds(struct mm_struct *mm)
2638 : {
2639 : if (mm_pmd_folded(mm))
2640 : return;
2641 2 : atomic_long_add(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2642 : }
2643 :
2644 : static inline void mm_dec_nr_pmds(struct mm_struct *mm)
2645 : {
2646 : if (mm_pmd_folded(mm))
2647 : return;
2648 0 : atomic_long_sub(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2649 : }
2650 : #endif
2651 :
2652 : #ifdef CONFIG_MMU
2653 : static inline void mm_pgtables_bytes_init(struct mm_struct *mm)
2654 : {
2655 0 : atomic_long_set(&mm->pgtables_bytes, 0);
2656 : }
2657 :
2658 : static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2659 : {
2660 0 : return atomic_long_read(&mm->pgtables_bytes);
2661 : }
2662 :
2663 : static inline void mm_inc_nr_ptes(struct mm_struct *mm)
2664 : {
2665 0 : atomic_long_add(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2666 : }
2667 :
2668 : static inline void mm_dec_nr_ptes(struct mm_struct *mm)
2669 : {
2670 0 : atomic_long_sub(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2671 : }
2672 : #else
2673 :
2674 : static inline void mm_pgtables_bytes_init(struct mm_struct *mm) {}
2675 : static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2676 : {
2677 : return 0;
2678 : }
2679 :
2680 : static inline void mm_inc_nr_ptes(struct mm_struct *mm) {}
2681 : static inline void mm_dec_nr_ptes(struct mm_struct *mm) {}
2682 : #endif
2683 :
2684 : int __pte_alloc(struct mm_struct *mm, pmd_t *pmd);
2685 : int __pte_alloc_kernel(pmd_t *pmd);
2686 :
2687 : #if defined(CONFIG_MMU)
2688 :
2689 : static inline p4d_t *p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
2690 : unsigned long address)
2691 : {
2692 0 : return (unlikely(pgd_none(*pgd)) && __p4d_alloc(mm, pgd, address)) ?
2693 0 : NULL : p4d_offset(pgd, address);
2694 : }
2695 :
2696 : static inline pud_t *pud_alloc(struct mm_struct *mm, p4d_t *p4d,
2697 : unsigned long address)
2698 : {
2699 0 : return (unlikely(p4d_none(*p4d)) && __pud_alloc(mm, p4d, address)) ?
2700 0 : NULL : pud_offset(p4d, address);
2701 : }
2702 :
2703 0 : static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
2704 : {
2705 0 : return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
2706 0 : NULL: pmd_offset(pud, address);
2707 : }
2708 : #endif /* CONFIG_MMU */
2709 :
2710 : #if USE_SPLIT_PTE_PTLOCKS
2711 : #if ALLOC_SPLIT_PTLOCKS
2712 : void __init ptlock_cache_init(void);
2713 : extern bool ptlock_alloc(struct page *page);
2714 : extern void ptlock_free(struct page *page);
2715 :
2716 : static inline spinlock_t *ptlock_ptr(struct page *page)
2717 : {
2718 : return page->ptl;
2719 : }
2720 : #else /* ALLOC_SPLIT_PTLOCKS */
2721 : static inline void ptlock_cache_init(void)
2722 : {
2723 : }
2724 :
2725 : static inline bool ptlock_alloc(struct page *page)
2726 : {
2727 : return true;
2728 : }
2729 :
2730 : static inline void ptlock_free(struct page *page)
2731 : {
2732 : }
2733 :
2734 : static inline spinlock_t *ptlock_ptr(struct page *page)
2735 : {
2736 : return &page->ptl;
2737 : }
2738 : #endif /* ALLOC_SPLIT_PTLOCKS */
2739 :
2740 : static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2741 : {
2742 : return ptlock_ptr(pmd_page(*pmd));
2743 : }
2744 :
2745 : static inline bool ptlock_init(struct page *page)
2746 : {
2747 : /*
2748 : * prep_new_page() initialize page->private (and therefore page->ptl)
2749 : * with 0. Make sure nobody took it in use in between.
2750 : *
2751 : * It can happen if arch try to use slab for page table allocation:
2752 : * slab code uses page->slab_cache, which share storage with page->ptl.
2753 : */
2754 : VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page);
2755 : if (!ptlock_alloc(page))
2756 : return false;
2757 : spin_lock_init(ptlock_ptr(page));
2758 : return true;
2759 : }
2760 :
2761 : #else /* !USE_SPLIT_PTE_PTLOCKS */
2762 : /*
2763 : * We use mm->page_table_lock to guard all pagetable pages of the mm.
2764 : */
2765 : static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2766 : {
2767 0 : return &mm->page_table_lock;
2768 : }
2769 : static inline void ptlock_cache_init(void) {}
2770 : static inline bool ptlock_init(struct page *page) { return true; }
2771 : static inline void ptlock_free(struct page *page) {}
2772 : #endif /* USE_SPLIT_PTE_PTLOCKS */
2773 :
2774 : static inline bool pgtable_pte_page_ctor(struct page *page)
2775 : {
2776 0 : if (!ptlock_init(page))
2777 : return false;
2778 0 : __SetPageTable(page);
2779 0 : inc_lruvec_page_state(page, NR_PAGETABLE);
2780 : return true;
2781 : }
2782 :
2783 : static inline void pgtable_pte_page_dtor(struct page *page)
2784 : {
2785 0 : ptlock_free(page);
2786 0 : __ClearPageTable(page);
2787 0 : dec_lruvec_page_state(page, NR_PAGETABLE);
2788 : }
2789 :
2790 : #define pte_offset_map_lock(mm, pmd, address, ptlp) \
2791 : ({ \
2792 : spinlock_t *__ptl = pte_lockptr(mm, pmd); \
2793 : pte_t *__pte = pte_offset_map(pmd, address); \
2794 : *(ptlp) = __ptl; \
2795 : spin_lock(__ptl); \
2796 : __pte; \
2797 : })
2798 :
2799 : #define pte_unmap_unlock(pte, ptl) do { \
2800 : spin_unlock(ptl); \
2801 : pte_unmap(pte); \
2802 : } while (0)
2803 :
2804 : #define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd))
2805 :
2806 : #define pte_alloc_map(mm, pmd, address) \
2807 : (pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address))
2808 :
2809 : #define pte_alloc_map_lock(mm, pmd, address, ptlp) \
2810 : (pte_alloc(mm, pmd) ? \
2811 : NULL : pte_offset_map_lock(mm, pmd, address, ptlp))
2812 :
2813 : #define pte_alloc_kernel(pmd, address) \
2814 : ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \
2815 : NULL: pte_offset_kernel(pmd, address))
2816 :
2817 : #if USE_SPLIT_PMD_PTLOCKS
2818 :
2819 : static inline struct page *pmd_pgtable_page(pmd_t *pmd)
2820 : {
2821 : unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
2822 : return virt_to_page((void *)((unsigned long) pmd & mask));
2823 : }
2824 :
2825 : static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
2826 : {
2827 : return ptlock_ptr(pmd_pgtable_page(pmd));
2828 : }
2829 :
2830 : static inline bool pmd_ptlock_init(struct page *page)
2831 : {
2832 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2833 : page->pmd_huge_pte = NULL;
2834 : #endif
2835 : return ptlock_init(page);
2836 : }
2837 :
2838 : static inline void pmd_ptlock_free(struct page *page)
2839 : {
2840 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2841 : VM_BUG_ON_PAGE(page->pmd_huge_pte, page);
2842 : #endif
2843 : ptlock_free(page);
2844 : }
2845 :
2846 : #define pmd_huge_pte(mm, pmd) (pmd_pgtable_page(pmd)->pmd_huge_pte)
2847 :
2848 : #else
2849 :
2850 : static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
2851 : {
2852 : return &mm->page_table_lock;
2853 : }
2854 :
2855 : static inline bool pmd_ptlock_init(struct page *page) { return true; }
2856 : static inline void pmd_ptlock_free(struct page *page) {}
2857 :
2858 : #define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte)
2859 :
2860 : #endif
2861 :
2862 : static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd)
2863 : {
2864 0 : spinlock_t *ptl = pmd_lockptr(mm, pmd);
2865 0 : spin_lock(ptl);
2866 : return ptl;
2867 : }
2868 :
2869 : static inline bool pgtable_pmd_page_ctor(struct page *page)
2870 : {
2871 1 : if (!pmd_ptlock_init(page))
2872 : return false;
2873 1 : __SetPageTable(page);
2874 2 : inc_lruvec_page_state(page, NR_PAGETABLE);
2875 : return true;
2876 : }
2877 :
2878 : static inline void pgtable_pmd_page_dtor(struct page *page)
2879 : {
2880 0 : pmd_ptlock_free(page);
2881 0 : __ClearPageTable(page);
2882 0 : dec_lruvec_page_state(page, NR_PAGETABLE);
2883 : }
2884 :
2885 : /*
2886 : * No scalability reason to split PUD locks yet, but follow the same pattern
2887 : * as the PMD locks to make it easier if we decide to. The VM should not be
2888 : * considered ready to switch to split PUD locks yet; there may be places
2889 : * which need to be converted from page_table_lock.
2890 : */
2891 : static inline spinlock_t *pud_lockptr(struct mm_struct *mm, pud_t *pud)
2892 : {
2893 : return &mm->page_table_lock;
2894 : }
2895 :
2896 : static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud)
2897 : {
2898 1 : spinlock_t *ptl = pud_lockptr(mm, pud);
2899 :
2900 1 : spin_lock(ptl);
2901 : return ptl;
2902 : }
2903 :
2904 : extern void __init pagecache_init(void);
2905 : extern void free_initmem(void);
2906 :
2907 : /*
2908 : * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
2909 : * into the buddy system. The freed pages will be poisoned with pattern
2910 : * "poison" if it's within range [0, UCHAR_MAX].
2911 : * Return pages freed into the buddy system.
2912 : */
2913 : extern unsigned long free_reserved_area(void *start, void *end,
2914 : int poison, const char *s);
2915 :
2916 : extern void adjust_managed_page_count(struct page *page, long count);
2917 :
2918 : extern void reserve_bootmem_region(phys_addr_t start, phys_addr_t end);
2919 :
2920 : /* Free the reserved page into the buddy system, so it gets managed. */
2921 : static inline void free_reserved_page(struct page *page)
2922 : {
2923 0 : ClearPageReserved(page);
2924 0 : init_page_count(page);
2925 0 : __free_page(page);
2926 0 : adjust_managed_page_count(page, 1);
2927 : }
2928 : #define free_highmem_page(page) free_reserved_page(page)
2929 :
2930 : static inline void mark_page_reserved(struct page *page)
2931 : {
2932 : SetPageReserved(page);
2933 : adjust_managed_page_count(page, -1);
2934 : }
2935 :
2936 : /*
2937 : * Default method to free all the __init memory into the buddy system.
2938 : * The freed pages will be poisoned with pattern "poison" if it's within
2939 : * range [0, UCHAR_MAX].
2940 : * Return pages freed into the buddy system.
2941 : */
2942 : static inline unsigned long free_initmem_default(int poison)
2943 : {
2944 : extern char __init_begin[], __init_end[];
2945 :
2946 0 : return free_reserved_area(&__init_begin, &__init_end,
2947 : poison, "unused kernel image (initmem)");
2948 : }
2949 :
2950 : static inline unsigned long get_num_physpages(void)
2951 : {
2952 : int nid;
2953 1 : unsigned long phys_pages = 0;
2954 :
2955 2 : for_each_online_node(nid)
2956 1 : phys_pages += node_present_pages(nid);
2957 :
2958 : return phys_pages;
2959 : }
2960 :
2961 : /*
2962 : * Using memblock node mappings, an architecture may initialise its
2963 : * zones, allocate the backing mem_map and account for memory holes in an
2964 : * architecture independent manner.
2965 : *
2966 : * An architecture is expected to register range of page frames backed by
2967 : * physical memory with memblock_add[_node]() before calling
2968 : * free_area_init() passing in the PFN each zone ends at. At a basic
2969 : * usage, an architecture is expected to do something like
2970 : *
2971 : * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
2972 : * max_highmem_pfn};
2973 : * for_each_valid_physical_page_range()
2974 : * memblock_add_node(base, size, nid, MEMBLOCK_NONE)
2975 : * free_area_init(max_zone_pfns);
2976 : */
2977 : void free_area_init(unsigned long *max_zone_pfn);
2978 : unsigned long node_map_pfn_alignment(void);
2979 : unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn,
2980 : unsigned long end_pfn);
2981 : extern unsigned long absent_pages_in_range(unsigned long start_pfn,
2982 : unsigned long end_pfn);
2983 : extern void get_pfn_range_for_nid(unsigned int nid,
2984 : unsigned long *start_pfn, unsigned long *end_pfn);
2985 :
2986 : #ifndef CONFIG_NUMA
2987 : static inline int early_pfn_to_nid(unsigned long pfn)
2988 : {
2989 : return 0;
2990 : }
2991 : #else
2992 : /* please see mm/page_alloc.c */
2993 : extern int __meminit early_pfn_to_nid(unsigned long pfn);
2994 : #endif
2995 :
2996 : extern void set_dma_reserve(unsigned long new_dma_reserve);
2997 : extern void memmap_init_range(unsigned long, int, unsigned long,
2998 : unsigned long, unsigned long, enum meminit_context,
2999 : struct vmem_altmap *, int migratetype);
3000 : extern void setup_per_zone_wmarks(void);
3001 : extern void calculate_min_free_kbytes(void);
3002 : extern int __meminit init_per_zone_wmark_min(void);
3003 : extern void mem_init(void);
3004 : extern void __init mmap_init(void);
3005 :
3006 : extern void __show_mem(unsigned int flags, nodemask_t *nodemask, int max_zone_idx);
3007 : static inline void show_mem(unsigned int flags, nodemask_t *nodemask)
3008 : {
3009 0 : __show_mem(flags, nodemask, MAX_NR_ZONES - 1);
3010 : }
3011 : extern long si_mem_available(void);
3012 : extern void si_meminfo(struct sysinfo * val);
3013 : extern void si_meminfo_node(struct sysinfo *val, int nid);
3014 : #ifdef __HAVE_ARCH_RESERVED_KERNEL_PAGES
3015 : extern unsigned long arch_reserved_kernel_pages(void);
3016 : #endif
3017 :
3018 : extern __printf(3, 4)
3019 : void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...);
3020 :
3021 : extern void setup_per_cpu_pageset(void);
3022 :
3023 : /* page_alloc.c */
3024 : extern int min_free_kbytes;
3025 : extern int watermark_boost_factor;
3026 : extern int watermark_scale_factor;
3027 :
3028 : /* nommu.c */
3029 : extern atomic_long_t mmap_pages_allocated;
3030 : extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
3031 :
3032 : /* interval_tree.c */
3033 : void vma_interval_tree_insert(struct vm_area_struct *node,
3034 : struct rb_root_cached *root);
3035 : void vma_interval_tree_insert_after(struct vm_area_struct *node,
3036 : struct vm_area_struct *prev,
3037 : struct rb_root_cached *root);
3038 : void vma_interval_tree_remove(struct vm_area_struct *node,
3039 : struct rb_root_cached *root);
3040 : struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root_cached *root,
3041 : unsigned long start, unsigned long last);
3042 : struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
3043 : unsigned long start, unsigned long last);
3044 :
3045 : #define vma_interval_tree_foreach(vma, root, start, last) \
3046 : for (vma = vma_interval_tree_iter_first(root, start, last); \
3047 : vma; vma = vma_interval_tree_iter_next(vma, start, last))
3048 :
3049 : void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
3050 : struct rb_root_cached *root);
3051 : void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
3052 : struct rb_root_cached *root);
3053 : struct anon_vma_chain *
3054 : anon_vma_interval_tree_iter_first(struct rb_root_cached *root,
3055 : unsigned long start, unsigned long last);
3056 : struct anon_vma_chain *anon_vma_interval_tree_iter_next(
3057 : struct anon_vma_chain *node, unsigned long start, unsigned long last);
3058 : #ifdef CONFIG_DEBUG_VM_RB
3059 : void anon_vma_interval_tree_verify(struct anon_vma_chain *node);
3060 : #endif
3061 :
3062 : #define anon_vma_interval_tree_foreach(avc, root, start, last) \
3063 : for (avc = anon_vma_interval_tree_iter_first(root, start, last); \
3064 : avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))
3065 :
3066 : /* mmap.c */
3067 : extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin);
3068 : extern int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma,
3069 : unsigned long start, unsigned long end, pgoff_t pgoff,
3070 : struct vm_area_struct *next);
3071 : extern int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma,
3072 : unsigned long start, unsigned long end, pgoff_t pgoff);
3073 : extern struct vm_area_struct *vma_merge(struct vma_iterator *vmi,
3074 : struct mm_struct *, struct vm_area_struct *prev, unsigned long addr,
3075 : unsigned long end, unsigned long vm_flags, struct anon_vma *,
3076 : struct file *, pgoff_t, struct mempolicy *, struct vm_userfaultfd_ctx,
3077 : struct anon_vma_name *);
3078 : extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
3079 : extern int __split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
3080 : unsigned long addr, int new_below);
3081 : extern int split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
3082 : unsigned long addr, int new_below);
3083 : extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
3084 : extern void unlink_file_vma(struct vm_area_struct *);
3085 : extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
3086 : unsigned long addr, unsigned long len, pgoff_t pgoff,
3087 : bool *need_rmap_locks);
3088 : extern void exit_mmap(struct mm_struct *);
3089 :
3090 : static inline int check_data_rlimit(unsigned long rlim,
3091 : unsigned long new,
3092 : unsigned long start,
3093 : unsigned long end_data,
3094 : unsigned long start_data)
3095 : {
3096 0 : if (rlim < RLIM_INFINITY) {
3097 0 : if (((new - start) + (end_data - start_data)) > rlim)
3098 : return -ENOSPC;
3099 : }
3100 :
3101 : return 0;
3102 : }
3103 :
3104 : extern int mm_take_all_locks(struct mm_struct *mm);
3105 : extern void mm_drop_all_locks(struct mm_struct *mm);
3106 :
3107 : extern int set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
3108 : extern int replace_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
3109 : extern struct file *get_mm_exe_file(struct mm_struct *mm);
3110 : extern struct file *get_task_exe_file(struct task_struct *task);
3111 :
3112 : extern bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long npages);
3113 : extern void vm_stat_account(struct mm_struct *, vm_flags_t, long npages);
3114 :
3115 : extern bool vma_is_special_mapping(const struct vm_area_struct *vma,
3116 : const struct vm_special_mapping *sm);
3117 : extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm,
3118 : unsigned long addr, unsigned long len,
3119 : unsigned long flags,
3120 : const struct vm_special_mapping *spec);
3121 : /* This is an obsolete alternative to _install_special_mapping. */
3122 : extern int install_special_mapping(struct mm_struct *mm,
3123 : unsigned long addr, unsigned long len,
3124 : unsigned long flags, struct page **pages);
3125 :
3126 : unsigned long randomize_stack_top(unsigned long stack_top);
3127 : unsigned long randomize_page(unsigned long start, unsigned long range);
3128 :
3129 : extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
3130 :
3131 : extern unsigned long mmap_region(struct file *file, unsigned long addr,
3132 : unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
3133 : struct list_head *uf);
3134 : extern unsigned long do_mmap(struct file *file, unsigned long addr,
3135 : unsigned long len, unsigned long prot, unsigned long flags,
3136 : unsigned long pgoff, unsigned long *populate, struct list_head *uf);
3137 : extern int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm,
3138 : unsigned long start, size_t len, struct list_head *uf,
3139 : bool downgrade);
3140 : extern int do_munmap(struct mm_struct *, unsigned long, size_t,
3141 : struct list_head *uf);
3142 : extern int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior);
3143 :
3144 : #ifdef CONFIG_MMU
3145 : extern int do_vma_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma,
3146 : unsigned long start, unsigned long end,
3147 : struct list_head *uf, bool downgrade);
3148 : extern int __mm_populate(unsigned long addr, unsigned long len,
3149 : int ignore_errors);
3150 : static inline void mm_populate(unsigned long addr, unsigned long len)
3151 : {
3152 : /* Ignore errors */
3153 0 : (void) __mm_populate(addr, len, 1);
3154 : }
3155 : #else
3156 : static inline void mm_populate(unsigned long addr, unsigned long len) {}
3157 : #endif
3158 :
3159 : /* These take the mm semaphore themselves */
3160 : extern int __must_check vm_brk(unsigned long, unsigned long);
3161 : extern int __must_check vm_brk_flags(unsigned long, unsigned long, unsigned long);
3162 : extern int vm_munmap(unsigned long, size_t);
3163 : extern unsigned long __must_check vm_mmap(struct file *, unsigned long,
3164 : unsigned long, unsigned long,
3165 : unsigned long, unsigned long);
3166 :
3167 : struct vm_unmapped_area_info {
3168 : #define VM_UNMAPPED_AREA_TOPDOWN 1
3169 : unsigned long flags;
3170 : unsigned long length;
3171 : unsigned long low_limit;
3172 : unsigned long high_limit;
3173 : unsigned long align_mask;
3174 : unsigned long align_offset;
3175 : };
3176 :
3177 : extern unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info);
3178 :
3179 : /* truncate.c */
3180 : extern void truncate_inode_pages(struct address_space *, loff_t);
3181 : extern void truncate_inode_pages_range(struct address_space *,
3182 : loff_t lstart, loff_t lend);
3183 : extern void truncate_inode_pages_final(struct address_space *);
3184 :
3185 : /* generic vm_area_ops exported for stackable file systems */
3186 : extern vm_fault_t filemap_fault(struct vm_fault *vmf);
3187 : extern vm_fault_t filemap_map_pages(struct vm_fault *vmf,
3188 : pgoff_t start_pgoff, pgoff_t end_pgoff);
3189 : extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf);
3190 :
3191 : extern unsigned long stack_guard_gap;
3192 : /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
3193 : extern int expand_stack(struct vm_area_struct *vma, unsigned long address);
3194 :
3195 : /* CONFIG_STACK_GROWSUP still needs to grow downwards at some places */
3196 : extern int expand_downwards(struct vm_area_struct *vma,
3197 : unsigned long address);
3198 : #if VM_GROWSUP
3199 : extern int expand_upwards(struct vm_area_struct *vma, unsigned long address);
3200 : #else
3201 : #define expand_upwards(vma, address) (0)
3202 : #endif
3203 :
3204 : /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */
3205 : extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
3206 : extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
3207 : struct vm_area_struct **pprev);
3208 :
3209 : /*
3210 : * Look up the first VMA which intersects the interval [start_addr, end_addr)
3211 : * NULL if none. Assume start_addr < end_addr.
3212 : */
3213 : struct vm_area_struct *find_vma_intersection(struct mm_struct *mm,
3214 : unsigned long start_addr, unsigned long end_addr);
3215 :
3216 : /**
3217 : * vma_lookup() - Find a VMA at a specific address
3218 : * @mm: The process address space.
3219 : * @addr: The user address.
3220 : *
3221 : * Return: The vm_area_struct at the given address, %NULL otherwise.
3222 : */
3223 : static inline
3224 : struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr)
3225 : {
3226 0 : return mtree_load(&mm->mm_mt, addr);
3227 : }
3228 :
3229 : static inline unsigned long vm_start_gap(struct vm_area_struct *vma)
3230 : {
3231 0 : unsigned long vm_start = vma->vm_start;
3232 :
3233 0 : if (vma->vm_flags & VM_GROWSDOWN) {
3234 0 : vm_start -= stack_guard_gap;
3235 0 : if (vm_start > vma->vm_start)
3236 0 : vm_start = 0;
3237 : }
3238 : return vm_start;
3239 : }
3240 :
3241 : static inline unsigned long vm_end_gap(struct vm_area_struct *vma)
3242 : {
3243 0 : unsigned long vm_end = vma->vm_end;
3244 :
3245 : if (vma->vm_flags & VM_GROWSUP) {
3246 : vm_end += stack_guard_gap;
3247 : if (vm_end < vma->vm_end)
3248 : vm_end = -PAGE_SIZE;
3249 : }
3250 : return vm_end;
3251 : }
3252 :
3253 : static inline unsigned long vma_pages(struct vm_area_struct *vma)
3254 : {
3255 0 : return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
3256 : }
3257 :
3258 : /* Look up the first VMA which exactly match the interval vm_start ... vm_end */
3259 : static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
3260 : unsigned long vm_start, unsigned long vm_end)
3261 : {
3262 0 : struct vm_area_struct *vma = vma_lookup(mm, vm_start);
3263 :
3264 0 : if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
3265 0 : vma = NULL;
3266 :
3267 : return vma;
3268 : }
3269 :
3270 : static inline bool range_in_vma(struct vm_area_struct *vma,
3271 : unsigned long start, unsigned long end)
3272 : {
3273 0 : return (vma && vma->vm_start <= start && end <= vma->vm_end);
3274 : }
3275 :
3276 : #ifdef CONFIG_MMU
3277 : pgprot_t vm_get_page_prot(unsigned long vm_flags);
3278 : void vma_set_page_prot(struct vm_area_struct *vma);
3279 : #else
3280 : static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
3281 : {
3282 : return __pgprot(0);
3283 : }
3284 : static inline void vma_set_page_prot(struct vm_area_struct *vma)
3285 : {
3286 : vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
3287 : }
3288 : #endif
3289 :
3290 : void vma_set_file(struct vm_area_struct *vma, struct file *file);
3291 :
3292 : #ifdef CONFIG_NUMA_BALANCING
3293 : unsigned long change_prot_numa(struct vm_area_struct *vma,
3294 : unsigned long start, unsigned long end);
3295 : #endif
3296 :
3297 : struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr);
3298 : int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
3299 : unsigned long pfn, unsigned long size, pgprot_t);
3300 : int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr,
3301 : unsigned long pfn, unsigned long size, pgprot_t prot);
3302 : int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
3303 : int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr,
3304 : struct page **pages, unsigned long *num);
3305 : int vm_map_pages(struct vm_area_struct *vma, struct page **pages,
3306 : unsigned long num);
3307 : int vm_map_pages_zero(struct vm_area_struct *vma, struct page **pages,
3308 : unsigned long num);
3309 : vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
3310 : unsigned long pfn);
3311 : vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
3312 : unsigned long pfn, pgprot_t pgprot);
3313 : vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
3314 : pfn_t pfn);
3315 : vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
3316 : unsigned long addr, pfn_t pfn);
3317 : int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
3318 :
3319 : static inline vm_fault_t vmf_insert_page(struct vm_area_struct *vma,
3320 : unsigned long addr, struct page *page)
3321 : {
3322 : int err = vm_insert_page(vma, addr, page);
3323 :
3324 : if (err == -ENOMEM)
3325 : return VM_FAULT_OOM;
3326 : if (err < 0 && err != -EBUSY)
3327 : return VM_FAULT_SIGBUS;
3328 :
3329 : return VM_FAULT_NOPAGE;
3330 : }
3331 :
3332 : #ifndef io_remap_pfn_range
3333 : static inline int io_remap_pfn_range(struct vm_area_struct *vma,
3334 : unsigned long addr, unsigned long pfn,
3335 : unsigned long size, pgprot_t prot)
3336 : {
3337 0 : return remap_pfn_range(vma, addr, pfn, size, pgprot_decrypted(prot));
3338 : }
3339 : #endif
3340 :
3341 : static inline vm_fault_t vmf_error(int err)
3342 : {
3343 0 : if (err == -ENOMEM)
3344 : return VM_FAULT_OOM;
3345 : return VM_FAULT_SIGBUS;
3346 : }
3347 :
3348 : struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
3349 : unsigned int foll_flags);
3350 :
3351 : static inline int vm_fault_to_errno(vm_fault_t vm_fault, int foll_flags)
3352 : {
3353 0 : if (vm_fault & VM_FAULT_OOM)
3354 : return -ENOMEM;
3355 0 : if (vm_fault & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE))
3356 0 : return (foll_flags & FOLL_HWPOISON) ? -EHWPOISON : -EFAULT;
3357 0 : if (vm_fault & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV))
3358 : return -EFAULT;
3359 : return 0;
3360 : }
3361 :
3362 : /*
3363 : * Indicates whether GUP can follow a PROT_NONE mapped page, or whether
3364 : * a (NUMA hinting) fault is required.
3365 : */
3366 : static inline bool gup_can_follow_protnone(unsigned int flags)
3367 : {
3368 : /*
3369 : * FOLL_FORCE has to be able to make progress even if the VMA is
3370 : * inaccessible. Further, FOLL_FORCE access usually does not represent
3371 : * application behaviour and we should avoid triggering NUMA hinting
3372 : * faults.
3373 : */
3374 : return flags & FOLL_FORCE;
3375 : }
3376 :
3377 : typedef int (*pte_fn_t)(pte_t *pte, unsigned long addr, void *data);
3378 : extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
3379 : unsigned long size, pte_fn_t fn, void *data);
3380 : extern int apply_to_existing_page_range(struct mm_struct *mm,
3381 : unsigned long address, unsigned long size,
3382 : pte_fn_t fn, void *data);
3383 :
3384 : #ifdef CONFIG_PAGE_POISONING
3385 : extern void __kernel_poison_pages(struct page *page, int numpages);
3386 : extern void __kernel_unpoison_pages(struct page *page, int numpages);
3387 : extern bool _page_poisoning_enabled_early;
3388 : DECLARE_STATIC_KEY_FALSE(_page_poisoning_enabled);
3389 : static inline bool page_poisoning_enabled(void)
3390 : {
3391 : return _page_poisoning_enabled_early;
3392 : }
3393 : /*
3394 : * For use in fast paths after init_mem_debugging() has run, or when a
3395 : * false negative result is not harmful when called too early.
3396 : */
3397 : static inline bool page_poisoning_enabled_static(void)
3398 : {
3399 : return static_branch_unlikely(&_page_poisoning_enabled);
3400 : }
3401 : static inline void kernel_poison_pages(struct page *page, int numpages)
3402 : {
3403 : if (page_poisoning_enabled_static())
3404 : __kernel_poison_pages(page, numpages);
3405 : }
3406 : static inline void kernel_unpoison_pages(struct page *page, int numpages)
3407 : {
3408 : if (page_poisoning_enabled_static())
3409 : __kernel_unpoison_pages(page, numpages);
3410 : }
3411 : #else
3412 : static inline bool page_poisoning_enabled(void) { return false; }
3413 : static inline bool page_poisoning_enabled_static(void) { return false; }
3414 : static inline void __kernel_poison_pages(struct page *page, int nunmpages) { }
3415 : static inline void kernel_poison_pages(struct page *page, int numpages) { }
3416 : static inline void kernel_unpoison_pages(struct page *page, int numpages) { }
3417 : #endif
3418 :
3419 : DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
3420 : static inline bool want_init_on_alloc(gfp_t flags)
3421 : {
3422 45038 : if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
3423 : &init_on_alloc))
3424 : return true;
3425 44763 : return flags & __GFP_ZERO;
3426 : }
3427 :
3428 : DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free);
3429 44236 : static inline bool want_init_on_free(void)
3430 : {
3431 89535 : return static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
3432 : &init_on_free);
3433 : }
3434 :
3435 : extern bool _debug_pagealloc_enabled_early;
3436 : DECLARE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
3437 :
3438 : static inline bool debug_pagealloc_enabled(void)
3439 : {
3440 : return IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) &&
3441 : _debug_pagealloc_enabled_early;
3442 : }
3443 :
3444 : /*
3445 : * For use in fast paths after init_debug_pagealloc() has run, or when a
3446 : * false negative result is not harmful when called too early.
3447 : */
3448 : static inline bool debug_pagealloc_enabled_static(void)
3449 : {
3450 : if (!IS_ENABLED(CONFIG_DEBUG_PAGEALLOC))
3451 : return false;
3452 :
3453 : return static_branch_unlikely(&_debug_pagealloc_enabled);
3454 : }
3455 :
3456 : #ifdef CONFIG_DEBUG_PAGEALLOC
3457 : /*
3458 : * To support DEBUG_PAGEALLOC architecture must ensure that
3459 : * __kernel_map_pages() never fails
3460 : */
3461 : extern void __kernel_map_pages(struct page *page, int numpages, int enable);
3462 :
3463 : static inline void debug_pagealloc_map_pages(struct page *page, int numpages)
3464 : {
3465 : if (debug_pagealloc_enabled_static())
3466 : __kernel_map_pages(page, numpages, 1);
3467 : }
3468 :
3469 : static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages)
3470 : {
3471 : if (debug_pagealloc_enabled_static())
3472 : __kernel_map_pages(page, numpages, 0);
3473 : }
3474 : #else /* CONFIG_DEBUG_PAGEALLOC */
3475 : static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {}
3476 : static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {}
3477 : #endif /* CONFIG_DEBUG_PAGEALLOC */
3478 :
3479 : #ifdef __HAVE_ARCH_GATE_AREA
3480 : extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
3481 : extern int in_gate_area_no_mm(unsigned long addr);
3482 : extern int in_gate_area(struct mm_struct *mm, unsigned long addr);
3483 : #else
3484 : static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
3485 : {
3486 : return NULL;
3487 : }
3488 : static inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
3489 : static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
3490 : {
3491 : return 0;
3492 : }
3493 : #endif /* __HAVE_ARCH_GATE_AREA */
3494 :
3495 : extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm);
3496 :
3497 : #ifdef CONFIG_SYSCTL
3498 : extern int sysctl_drop_caches;
3499 : int drop_caches_sysctl_handler(struct ctl_table *, int, void *, size_t *,
3500 : loff_t *);
3501 : #endif
3502 :
3503 : void drop_slab(void);
3504 :
3505 : #ifndef CONFIG_MMU
3506 : #define randomize_va_space 0
3507 : #else
3508 : extern int randomize_va_space;
3509 : #endif
3510 :
3511 : const char * arch_vma_name(struct vm_area_struct *vma);
3512 : #ifdef CONFIG_MMU
3513 : void print_vma_addr(char *prefix, unsigned long rip);
3514 : #else
3515 : static inline void print_vma_addr(char *prefix, unsigned long rip)
3516 : {
3517 : }
3518 : #endif
3519 :
3520 : void *sparse_buffer_alloc(unsigned long size);
3521 : struct page * __populate_section_memmap(unsigned long pfn,
3522 : unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
3523 : struct dev_pagemap *pgmap);
3524 : void pmd_init(void *addr);
3525 : void pud_init(void *addr);
3526 : pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
3527 : p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node);
3528 : pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node);
3529 : pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
3530 : pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
3531 : struct vmem_altmap *altmap, struct page *reuse);
3532 : void *vmemmap_alloc_block(unsigned long size, int node);
3533 : struct vmem_altmap;
3534 : void *vmemmap_alloc_block_buf(unsigned long size, int node,
3535 : struct vmem_altmap *altmap);
3536 : void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
3537 : void vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
3538 : unsigned long addr, unsigned long next);
3539 : int vmemmap_check_pmd(pmd_t *pmd, int node,
3540 : unsigned long addr, unsigned long next);
3541 : int vmemmap_populate_basepages(unsigned long start, unsigned long end,
3542 : int node, struct vmem_altmap *altmap);
3543 : int vmemmap_populate_hugepages(unsigned long start, unsigned long end,
3544 : int node, struct vmem_altmap *altmap);
3545 : int vmemmap_populate(unsigned long start, unsigned long end, int node,
3546 : struct vmem_altmap *altmap);
3547 : void vmemmap_populate_print_last(void);
3548 : #ifdef CONFIG_MEMORY_HOTPLUG
3549 : void vmemmap_free(unsigned long start, unsigned long end,
3550 : struct vmem_altmap *altmap);
3551 : #endif
3552 :
3553 : #ifdef CONFIG_ARCH_WANT_OPTIMIZE_VMEMMAP
3554 : static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap,
3555 : struct dev_pagemap *pgmap)
3556 : {
3557 : return is_power_of_2(sizeof(struct page)) &&
3558 : pgmap && (pgmap_vmemmap_nr(pgmap) > 1) && !altmap;
3559 : }
3560 : #else
3561 : static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap,
3562 : struct dev_pagemap *pgmap)
3563 : {
3564 : return false;
3565 : }
3566 : #endif
3567 :
3568 : void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
3569 : unsigned long nr_pages);
3570 :
3571 : enum mf_flags {
3572 : MF_COUNT_INCREASED = 1 << 0,
3573 : MF_ACTION_REQUIRED = 1 << 1,
3574 : MF_MUST_KILL = 1 << 2,
3575 : MF_SOFT_OFFLINE = 1 << 3,
3576 : MF_UNPOISON = 1 << 4,
3577 : MF_SW_SIMULATED = 1 << 5,
3578 : MF_NO_RETRY = 1 << 6,
3579 : };
3580 : int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index,
3581 : unsigned long count, int mf_flags);
3582 : extern int memory_failure(unsigned long pfn, int flags);
3583 : extern void memory_failure_queue_kick(int cpu);
3584 : extern int unpoison_memory(unsigned long pfn);
3585 : extern void shake_page(struct page *p);
3586 : extern atomic_long_t num_poisoned_pages __read_mostly;
3587 : extern int soft_offline_page(unsigned long pfn, int flags);
3588 : #ifdef CONFIG_MEMORY_FAILURE
3589 : extern void memory_failure_queue(unsigned long pfn, int flags);
3590 : extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
3591 : bool *migratable_cleared);
3592 : void num_poisoned_pages_inc(unsigned long pfn);
3593 : void num_poisoned_pages_sub(unsigned long pfn, long i);
3594 : struct task_struct *task_early_kill(struct task_struct *tsk, int force_early);
3595 : #else
3596 : static inline void memory_failure_queue(unsigned long pfn, int flags)
3597 : {
3598 : }
3599 :
3600 : static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
3601 : bool *migratable_cleared)
3602 : {
3603 : return 0;
3604 : }
3605 :
3606 : static inline void num_poisoned_pages_inc(unsigned long pfn)
3607 : {
3608 : }
3609 :
3610 : static inline void num_poisoned_pages_sub(unsigned long pfn, long i)
3611 : {
3612 : }
3613 : #endif
3614 :
3615 : #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_KSM)
3616 : void add_to_kill_ksm(struct task_struct *tsk, struct page *p,
3617 : struct vm_area_struct *vma, struct list_head *to_kill,
3618 : unsigned long ksm_addr);
3619 : #endif
3620 :
3621 : #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG)
3622 : extern void memblk_nr_poison_inc(unsigned long pfn);
3623 : extern void memblk_nr_poison_sub(unsigned long pfn, long i);
3624 : #else
3625 : static inline void memblk_nr_poison_inc(unsigned long pfn)
3626 : {
3627 : }
3628 :
3629 : static inline void memblk_nr_poison_sub(unsigned long pfn, long i)
3630 : {
3631 : }
3632 : #endif
3633 :
3634 : #ifndef arch_memory_failure
3635 : static inline int arch_memory_failure(unsigned long pfn, int flags)
3636 : {
3637 : return -ENXIO;
3638 : }
3639 : #endif
3640 :
3641 : #ifndef arch_is_platform_page
3642 : static inline bool arch_is_platform_page(u64 paddr)
3643 : {
3644 : return false;
3645 : }
3646 : #endif
3647 :
3648 : /*
3649 : * Error handlers for various types of pages.
3650 : */
3651 : enum mf_result {
3652 : MF_IGNORED, /* Error: cannot be handled */
3653 : MF_FAILED, /* Error: handling failed */
3654 : MF_DELAYED, /* Will be handled later */
3655 : MF_RECOVERED, /* Successfully recovered */
3656 : };
3657 :
3658 : enum mf_action_page_type {
3659 : MF_MSG_KERNEL,
3660 : MF_MSG_KERNEL_HIGH_ORDER,
3661 : MF_MSG_SLAB,
3662 : MF_MSG_DIFFERENT_COMPOUND,
3663 : MF_MSG_HUGE,
3664 : MF_MSG_FREE_HUGE,
3665 : MF_MSG_UNMAP_FAILED,
3666 : MF_MSG_DIRTY_SWAPCACHE,
3667 : MF_MSG_CLEAN_SWAPCACHE,
3668 : MF_MSG_DIRTY_MLOCKED_LRU,
3669 : MF_MSG_CLEAN_MLOCKED_LRU,
3670 : MF_MSG_DIRTY_UNEVICTABLE_LRU,
3671 : MF_MSG_CLEAN_UNEVICTABLE_LRU,
3672 : MF_MSG_DIRTY_LRU,
3673 : MF_MSG_CLEAN_LRU,
3674 : MF_MSG_TRUNCATED_LRU,
3675 : MF_MSG_BUDDY,
3676 : MF_MSG_DAX,
3677 : MF_MSG_UNSPLIT_THP,
3678 : MF_MSG_UNKNOWN,
3679 : };
3680 :
3681 : /*
3682 : * Sysfs entries for memory failure handling statistics.
3683 : */
3684 : extern const struct attribute_group memory_failure_attr_group;
3685 :
3686 : #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
3687 : extern void clear_huge_page(struct page *page,
3688 : unsigned long addr_hint,
3689 : unsigned int pages_per_huge_page);
3690 : int copy_user_large_folio(struct folio *dst, struct folio *src,
3691 : unsigned long addr_hint,
3692 : struct vm_area_struct *vma);
3693 : long copy_folio_from_user(struct folio *dst_folio,
3694 : const void __user *usr_src,
3695 : bool allow_pagefault);
3696 :
3697 : /**
3698 : * vma_is_special_huge - Are transhuge page-table entries considered special?
3699 : * @vma: Pointer to the struct vm_area_struct to consider
3700 : *
3701 : * Whether transhuge page-table entries are considered "special" following
3702 : * the definition in vm_normal_page().
3703 : *
3704 : * Return: true if transhuge page-table entries should be considered special,
3705 : * false otherwise.
3706 : */
3707 : static inline bool vma_is_special_huge(const struct vm_area_struct *vma)
3708 : {
3709 : return vma_is_dax(vma) || (vma->vm_file &&
3710 : (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)));
3711 : }
3712 :
3713 : #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
3714 :
3715 : #ifdef CONFIG_DEBUG_PAGEALLOC
3716 : extern unsigned int _debug_guardpage_minorder;
3717 : DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
3718 :
3719 : static inline unsigned int debug_guardpage_minorder(void)
3720 : {
3721 : return _debug_guardpage_minorder;
3722 : }
3723 :
3724 : static inline bool debug_guardpage_enabled(void)
3725 : {
3726 : return static_branch_unlikely(&_debug_guardpage_enabled);
3727 : }
3728 :
3729 : static inline bool page_is_guard(struct page *page)
3730 : {
3731 : if (!debug_guardpage_enabled())
3732 : return false;
3733 :
3734 : return PageGuard(page);
3735 : }
3736 : #else
3737 : static inline unsigned int debug_guardpage_minorder(void) { return 0; }
3738 : static inline bool debug_guardpage_enabled(void) { return false; }
3739 : static inline bool page_is_guard(struct page *page) { return false; }
3740 : #endif /* CONFIG_DEBUG_PAGEALLOC */
3741 :
3742 : #if MAX_NUMNODES > 1
3743 : void __init setup_nr_node_ids(void);
3744 : #else
3745 : static inline void setup_nr_node_ids(void) {}
3746 : #endif
3747 :
3748 : extern int memcmp_pages(struct page *page1, struct page *page2);
3749 :
3750 : static inline int pages_identical(struct page *page1, struct page *page2)
3751 : {
3752 : return !memcmp_pages(page1, page2);
3753 : }
3754 :
3755 : #ifdef CONFIG_MAPPING_DIRTY_HELPERS
3756 : unsigned long clean_record_shared_mapping_range(struct address_space *mapping,
3757 : pgoff_t first_index, pgoff_t nr,
3758 : pgoff_t bitmap_pgoff,
3759 : unsigned long *bitmap,
3760 : pgoff_t *start,
3761 : pgoff_t *end);
3762 :
3763 : unsigned long wp_shared_mapping_range(struct address_space *mapping,
3764 : pgoff_t first_index, pgoff_t nr);
3765 : #endif
3766 :
3767 : extern int sysctl_nr_trim_pages;
3768 :
3769 : #ifdef CONFIG_PRINTK
3770 : void mem_dump_obj(void *object);
3771 : #else
3772 : static inline void mem_dump_obj(void *object) {}
3773 : #endif
3774 :
3775 : /**
3776 : * seal_check_future_write - Check for F_SEAL_FUTURE_WRITE flag and handle it
3777 : * @seals: the seals to check
3778 : * @vma: the vma to operate on
3779 : *
3780 : * Check whether F_SEAL_FUTURE_WRITE is set; if so, do proper check/handling on
3781 : * the vma flags. Return 0 if check pass, or <0 for errors.
3782 : */
3783 : static inline int seal_check_future_write(int seals, struct vm_area_struct *vma)
3784 : {
3785 0 : if (seals & F_SEAL_FUTURE_WRITE) {
3786 : /*
3787 : * New PROT_WRITE and MAP_SHARED mmaps are not allowed when
3788 : * "future write" seal active.
3789 : */
3790 0 : if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE))
3791 : return -EPERM;
3792 :
3793 : /*
3794 : * Since an F_SEAL_FUTURE_WRITE sealed memfd can be mapped as
3795 : * MAP_SHARED and read-only, take care to not allow mprotect to
3796 : * revert protections on such mappings. Do this only for shared
3797 : * mappings. For private mappings, don't need to mask
3798 : * VM_MAYWRITE as we still want them to be COW-writable.
3799 : */
3800 0 : if (vma->vm_flags & VM_SHARED)
3801 0 : vm_flags_clear(vma, VM_MAYWRITE);
3802 : }
3803 :
3804 : return 0;
3805 : }
3806 :
3807 : #ifdef CONFIG_ANON_VMA_NAME
3808 : int madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
3809 : unsigned long len_in,
3810 : struct anon_vma_name *anon_name);
3811 : #else
3812 : static inline int
3813 : madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
3814 : unsigned long len_in, struct anon_vma_name *anon_name) {
3815 : return 0;
3816 : }
3817 : #endif
3818 :
3819 : #endif /* _LINUX_MM_H */
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