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 24 : 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 265447 : 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 265447 : _pp[6] = 0;
165 265447 : _pp[5] = 0;
166 265447 : _pp[4] = 0;
167 265447 : _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 | VM_STACK_EARLY)
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 : #define VM_STACK_EARLY VM_GROWSDOWN
403 : #else
404 : #define VM_STACK VM_GROWSDOWN
405 : #define VM_STACK_EARLY 0
406 : #endif
407 :
408 : #define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
409 :
410 : /* VMA basic access permission flags */
411 : #define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC)
412 :
413 :
414 : /*
415 : * Special vmas that are non-mergable, non-mlock()able.
416 : */
417 : #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP)
418 :
419 : /* This mask prevents VMA from being scanned with khugepaged */
420 : #define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB)
421 :
422 : /* This mask defines which mm->def_flags a process can inherit its parent */
423 : #define VM_INIT_DEF_MASK VM_NOHUGEPAGE
424 :
425 : /* This mask represents all the VMA flag bits used by mlock */
426 : #define VM_LOCKED_MASK (VM_LOCKED | VM_LOCKONFAULT)
427 :
428 : /* Arch-specific flags to clear when updating VM flags on protection change */
429 : #ifndef VM_ARCH_CLEAR
430 : # define VM_ARCH_CLEAR VM_NONE
431 : #endif
432 : #define VM_FLAGS_CLEAR (ARCH_VM_PKEY_FLAGS | VM_ARCH_CLEAR)
433 :
434 : /*
435 : * mapping from the currently active vm_flags protection bits (the
436 : * low four bits) to a page protection mask..
437 : */
438 :
439 : /*
440 : * The default fault flags that should be used by most of the
441 : * arch-specific page fault handlers.
442 : */
443 : #define FAULT_FLAG_DEFAULT (FAULT_FLAG_ALLOW_RETRY | \
444 : FAULT_FLAG_KILLABLE | \
445 : FAULT_FLAG_INTERRUPTIBLE)
446 :
447 : /**
448 : * fault_flag_allow_retry_first - check ALLOW_RETRY the first time
449 : * @flags: Fault flags.
450 : *
451 : * This is mostly used for places where we want to try to avoid taking
452 : * the mmap_lock for too long a time when waiting for another condition
453 : * to change, in which case we can try to be polite to release the
454 : * mmap_lock in the first round to avoid potential starvation of other
455 : * processes that would also want the mmap_lock.
456 : *
457 : * Return: true if the page fault allows retry and this is the first
458 : * attempt of the fault handling; false otherwise.
459 : */
460 : static inline bool fault_flag_allow_retry_first(enum fault_flag flags)
461 : {
462 0 : return (flags & FAULT_FLAG_ALLOW_RETRY) &&
463 : (!(flags & FAULT_FLAG_TRIED));
464 : }
465 :
466 : #define FAULT_FLAG_TRACE \
467 : { FAULT_FLAG_WRITE, "WRITE" }, \
468 : { FAULT_FLAG_MKWRITE, "MKWRITE" }, \
469 : { FAULT_FLAG_ALLOW_RETRY, "ALLOW_RETRY" }, \
470 : { FAULT_FLAG_RETRY_NOWAIT, "RETRY_NOWAIT" }, \
471 : { FAULT_FLAG_KILLABLE, "KILLABLE" }, \
472 : { FAULT_FLAG_TRIED, "TRIED" }, \
473 : { FAULT_FLAG_USER, "USER" }, \
474 : { FAULT_FLAG_REMOTE, "REMOTE" }, \
475 : { FAULT_FLAG_INSTRUCTION, "INSTRUCTION" }, \
476 : { FAULT_FLAG_INTERRUPTIBLE, "INTERRUPTIBLE" }, \
477 : { FAULT_FLAG_VMA_LOCK, "VMA_LOCK" }
478 :
479 : /*
480 : * vm_fault is filled by the pagefault handler and passed to the vma's
481 : * ->fault function. The vma's ->fault is responsible for returning a bitmask
482 : * of VM_FAULT_xxx flags that give details about how the fault was handled.
483 : *
484 : * MM layer fills up gfp_mask for page allocations but fault handler might
485 : * alter it if its implementation requires a different allocation context.
486 : *
487 : * pgoff should be used in favour of virtual_address, if possible.
488 : */
489 : struct vm_fault {
490 : const struct {
491 : struct vm_area_struct *vma; /* Target VMA */
492 : gfp_t gfp_mask; /* gfp mask to be used for allocations */
493 : pgoff_t pgoff; /* Logical page offset based on vma */
494 : unsigned long address; /* Faulting virtual address - masked */
495 : unsigned long real_address; /* Faulting virtual address - unmasked */
496 : };
497 : enum fault_flag flags; /* FAULT_FLAG_xxx flags
498 : * XXX: should really be 'const' */
499 : pmd_t *pmd; /* Pointer to pmd entry matching
500 : * the 'address' */
501 : pud_t *pud; /* Pointer to pud entry matching
502 : * the 'address'
503 : */
504 : union {
505 : pte_t orig_pte; /* Value of PTE at the time of fault */
506 : pmd_t orig_pmd; /* Value of PMD at the time of fault,
507 : * used by PMD fault only.
508 : */
509 : };
510 :
511 : struct page *cow_page; /* Page handler may use for COW fault */
512 : struct page *page; /* ->fault handlers should return a
513 : * page here, unless VM_FAULT_NOPAGE
514 : * is set (which is also implied by
515 : * VM_FAULT_ERROR).
516 : */
517 : /* These three entries are valid only while holding ptl lock */
518 : pte_t *pte; /* Pointer to pte entry matching
519 : * the 'address'. NULL if the page
520 : * table hasn't been allocated.
521 : */
522 : spinlock_t *ptl; /* Page table lock.
523 : * Protects pte page table if 'pte'
524 : * is not NULL, otherwise pmd.
525 : */
526 : pgtable_t prealloc_pte; /* Pre-allocated pte page table.
527 : * vm_ops->map_pages() sets up a page
528 : * table from atomic context.
529 : * do_fault_around() pre-allocates
530 : * page table to avoid allocation from
531 : * atomic context.
532 : */
533 : };
534 :
535 : /* page entry size for vm->huge_fault() */
536 : enum page_entry_size {
537 : PE_SIZE_PTE = 0,
538 : PE_SIZE_PMD,
539 : PE_SIZE_PUD,
540 : };
541 :
542 : /*
543 : * These are the virtual MM functions - opening of an area, closing and
544 : * unmapping it (needed to keep files on disk up-to-date etc), pointer
545 : * to the functions called when a no-page or a wp-page exception occurs.
546 : */
547 : struct vm_operations_struct {
548 : void (*open)(struct vm_area_struct * area);
549 : /**
550 : * @close: Called when the VMA is being removed from the MM.
551 : * Context: User context. May sleep. Caller holds mmap_lock.
552 : */
553 : void (*close)(struct vm_area_struct * area);
554 : /* Called any time before splitting to check if it's allowed */
555 : int (*may_split)(struct vm_area_struct *area, unsigned long addr);
556 : int (*mremap)(struct vm_area_struct *area);
557 : /*
558 : * Called by mprotect() to make driver-specific permission
559 : * checks before mprotect() is finalised. The VMA must not
560 : * be modified. Returns 0 if mprotect() can proceed.
561 : */
562 : int (*mprotect)(struct vm_area_struct *vma, unsigned long start,
563 : unsigned long end, unsigned long newflags);
564 : vm_fault_t (*fault)(struct vm_fault *vmf);
565 : vm_fault_t (*huge_fault)(struct vm_fault *vmf,
566 : enum page_entry_size pe_size);
567 : vm_fault_t (*map_pages)(struct vm_fault *vmf,
568 : pgoff_t start_pgoff, pgoff_t end_pgoff);
569 : unsigned long (*pagesize)(struct vm_area_struct * area);
570 :
571 : /* notification that a previously read-only page is about to become
572 : * writable, if an error is returned it will cause a SIGBUS */
573 : vm_fault_t (*page_mkwrite)(struct vm_fault *vmf);
574 :
575 : /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */
576 : vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf);
577 :
578 : /* called by access_process_vm when get_user_pages() fails, typically
579 : * for use by special VMAs. See also generic_access_phys() for a generic
580 : * implementation useful for any iomem mapping.
581 : */
582 : int (*access)(struct vm_area_struct *vma, unsigned long addr,
583 : void *buf, int len, int write);
584 :
585 : /* Called by the /proc/PID/maps code to ask the vma whether it
586 : * has a special name. Returning non-NULL will also cause this
587 : * vma to be dumped unconditionally. */
588 : const char *(*name)(struct vm_area_struct *vma);
589 :
590 : #ifdef CONFIG_NUMA
591 : /*
592 : * set_policy() op must add a reference to any non-NULL @new mempolicy
593 : * to hold the policy upon return. Caller should pass NULL @new to
594 : * remove a policy and fall back to surrounding context--i.e. do not
595 : * install a MPOL_DEFAULT policy, nor the task or system default
596 : * mempolicy.
597 : */
598 : int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
599 :
600 : /*
601 : * get_policy() op must add reference [mpol_get()] to any policy at
602 : * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure
603 : * in mm/mempolicy.c will do this automatically.
604 : * get_policy() must NOT add a ref if the policy at (vma,addr) is not
605 : * marked as MPOL_SHARED. vma policies are protected by the mmap_lock.
606 : * If no [shared/vma] mempolicy exists at the addr, get_policy() op
607 : * must return NULL--i.e., do not "fallback" to task or system default
608 : * policy.
609 : */
610 : struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
611 : unsigned long addr);
612 : #endif
613 : /*
614 : * Called by vm_normal_page() for special PTEs to find the
615 : * page for @addr. This is useful if the default behavior
616 : * (using pte_page()) would not find the correct page.
617 : */
618 : struct page *(*find_special_page)(struct vm_area_struct *vma,
619 : unsigned long addr);
620 : };
621 :
622 : #ifdef CONFIG_NUMA_BALANCING
623 : static inline void vma_numab_state_init(struct vm_area_struct *vma)
624 : {
625 : vma->numab_state = NULL;
626 : }
627 : static inline void vma_numab_state_free(struct vm_area_struct *vma)
628 : {
629 : kfree(vma->numab_state);
630 : }
631 : #else
632 : static inline void vma_numab_state_init(struct vm_area_struct *vma) {}
633 : static inline void vma_numab_state_free(struct vm_area_struct *vma) {}
634 : #endif /* CONFIG_NUMA_BALANCING */
635 :
636 : #ifdef CONFIG_PER_VMA_LOCK
637 : /*
638 : * Try to read-lock a vma. The function is allowed to occasionally yield false
639 : * locked result to avoid performance overhead, in which case we fall back to
640 : * using mmap_lock. The function should never yield false unlocked result.
641 : */
642 : static inline bool vma_start_read(struct vm_area_struct *vma)
643 : {
644 : /* Check before locking. A race might cause false locked result. */
645 : if (vma->vm_lock_seq == READ_ONCE(vma->vm_mm->mm_lock_seq))
646 : return false;
647 :
648 : if (unlikely(down_read_trylock(&vma->vm_lock->lock) == 0))
649 : return false;
650 :
651 : /*
652 : * Overflow might produce false locked result.
653 : * False unlocked result is impossible because we modify and check
654 : * vma->vm_lock_seq under vma->vm_lock protection and mm->mm_lock_seq
655 : * modification invalidates all existing locks.
656 : */
657 : if (unlikely(vma->vm_lock_seq == READ_ONCE(vma->vm_mm->mm_lock_seq))) {
658 : up_read(&vma->vm_lock->lock);
659 : return false;
660 : }
661 : return true;
662 : }
663 :
664 : static inline void vma_end_read(struct vm_area_struct *vma)
665 : {
666 : rcu_read_lock(); /* keeps vma alive till the end of up_read */
667 : up_read(&vma->vm_lock->lock);
668 : rcu_read_unlock();
669 : }
670 :
671 : static bool __is_vma_write_locked(struct vm_area_struct *vma, int *mm_lock_seq)
672 : {
673 : mmap_assert_write_locked(vma->vm_mm);
674 :
675 : /*
676 : * current task is holding mmap_write_lock, both vma->vm_lock_seq and
677 : * mm->mm_lock_seq can't be concurrently modified.
678 : */
679 : *mm_lock_seq = READ_ONCE(vma->vm_mm->mm_lock_seq);
680 : return (vma->vm_lock_seq == *mm_lock_seq);
681 : }
682 :
683 : static inline void vma_start_write(struct vm_area_struct *vma)
684 : {
685 : int mm_lock_seq;
686 :
687 : if (__is_vma_write_locked(vma, &mm_lock_seq))
688 : return;
689 :
690 : down_write(&vma->vm_lock->lock);
691 : vma->vm_lock_seq = mm_lock_seq;
692 : up_write(&vma->vm_lock->lock);
693 : }
694 :
695 : static inline bool vma_try_start_write(struct vm_area_struct *vma)
696 : {
697 : int mm_lock_seq;
698 :
699 : if (__is_vma_write_locked(vma, &mm_lock_seq))
700 : return true;
701 :
702 : if (!down_write_trylock(&vma->vm_lock->lock))
703 : return false;
704 :
705 : vma->vm_lock_seq = mm_lock_seq;
706 : up_write(&vma->vm_lock->lock);
707 : return true;
708 : }
709 :
710 : static inline void vma_assert_write_locked(struct vm_area_struct *vma)
711 : {
712 : int mm_lock_seq;
713 :
714 : VM_BUG_ON_VMA(!__is_vma_write_locked(vma, &mm_lock_seq), vma);
715 : }
716 :
717 : static inline void vma_mark_detached(struct vm_area_struct *vma, bool detached)
718 : {
719 : /* When detaching vma should be write-locked */
720 : if (detached)
721 : vma_assert_write_locked(vma);
722 : vma->detached = detached;
723 : }
724 :
725 : struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm,
726 : unsigned long address);
727 :
728 : #else /* CONFIG_PER_VMA_LOCK */
729 :
730 : static inline bool vma_start_read(struct vm_area_struct *vma)
731 : { return false; }
732 : static inline void vma_end_read(struct vm_area_struct *vma) {}
733 : static inline void vma_start_write(struct vm_area_struct *vma) {}
734 : static inline bool vma_try_start_write(struct vm_area_struct *vma)
735 : { return true; }
736 : static inline void vma_assert_write_locked(struct vm_area_struct *vma) {}
737 : static inline void vma_mark_detached(struct vm_area_struct *vma,
738 : bool detached) {}
739 :
740 : #endif /* CONFIG_PER_VMA_LOCK */
741 :
742 : /*
743 : * WARNING: vma_init does not initialize vma->vm_lock.
744 : * Use vm_area_alloc()/vm_area_free() if vma needs locking.
745 : */
746 0 : static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm)
747 : {
748 : static const struct vm_operations_struct dummy_vm_ops = {};
749 :
750 0 : memset(vma, 0, sizeof(*vma));
751 0 : vma->vm_mm = mm;
752 0 : vma->vm_ops = &dummy_vm_ops;
753 0 : INIT_LIST_HEAD(&vma->anon_vma_chain);
754 0 : vma_mark_detached(vma, false);
755 0 : vma_numab_state_init(vma);
756 0 : }
757 :
758 : /* Use when VMA is not part of the VMA tree and needs no locking */
759 : static inline void vm_flags_init(struct vm_area_struct *vma,
760 : vm_flags_t flags)
761 : {
762 0 : ACCESS_PRIVATE(vma, __vm_flags) = flags;
763 : }
764 :
765 : /* Use when VMA is part of the VMA tree and modifications need coordination */
766 : static inline void vm_flags_reset(struct vm_area_struct *vma,
767 : vm_flags_t flags)
768 : {
769 0 : vma_start_write(vma);
770 0 : vm_flags_init(vma, flags);
771 : }
772 :
773 : static inline void vm_flags_reset_once(struct vm_area_struct *vma,
774 : vm_flags_t flags)
775 : {
776 0 : vma_start_write(vma);
777 0 : WRITE_ONCE(ACCESS_PRIVATE(vma, __vm_flags), flags);
778 : }
779 :
780 : static inline void vm_flags_set(struct vm_area_struct *vma,
781 : vm_flags_t flags)
782 : {
783 0 : vma_start_write(vma);
784 0 : ACCESS_PRIVATE(vma, __vm_flags) |= flags;
785 : }
786 :
787 : static inline void vm_flags_clear(struct vm_area_struct *vma,
788 : vm_flags_t flags)
789 : {
790 0 : vma_start_write(vma);
791 0 : ACCESS_PRIVATE(vma, __vm_flags) &= ~flags;
792 : }
793 :
794 : /*
795 : * Use only if VMA is not part of the VMA tree or has no other users and
796 : * therefore needs no locking.
797 : */
798 : static inline void __vm_flags_mod(struct vm_area_struct *vma,
799 : vm_flags_t set, vm_flags_t clear)
800 : {
801 : vm_flags_init(vma, (vma->vm_flags | set) & ~clear);
802 : }
803 :
804 : /*
805 : * Use only when the order of set/clear operations is unimportant, otherwise
806 : * use vm_flags_{set|clear} explicitly.
807 : */
808 : static inline void vm_flags_mod(struct vm_area_struct *vma,
809 : vm_flags_t set, vm_flags_t clear)
810 : {
811 : vma_start_write(vma);
812 : __vm_flags_mod(vma, set, clear);
813 : }
814 :
815 : static inline void vma_set_anonymous(struct vm_area_struct *vma)
816 : {
817 0 : vma->vm_ops = NULL;
818 : }
819 :
820 : static inline bool vma_is_anonymous(struct vm_area_struct *vma)
821 : {
822 0 : return !vma->vm_ops;
823 : }
824 :
825 : static inline bool vma_is_temporary_stack(struct vm_area_struct *vma)
826 : {
827 0 : int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP);
828 :
829 0 : if (!maybe_stack)
830 : return false;
831 :
832 0 : if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) ==
833 : VM_STACK_INCOMPLETE_SETUP)
834 : return true;
835 :
836 : return false;
837 : }
838 :
839 : static inline bool vma_is_foreign(struct vm_area_struct *vma)
840 : {
841 : if (!current->mm)
842 : return true;
843 :
844 : if (current->mm != vma->vm_mm)
845 : return true;
846 :
847 : return false;
848 : }
849 :
850 : static inline bool vma_is_accessible(struct vm_area_struct *vma)
851 : {
852 0 : return vma->vm_flags & VM_ACCESS_FLAGS;
853 : }
854 :
855 : static inline
856 : struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max)
857 : {
858 0 : return mas_find(&vmi->mas, max - 1);
859 : }
860 :
861 : static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi)
862 : {
863 : /*
864 : * Uses mas_find() to get the first VMA when the iterator starts.
865 : * Calling mas_next() could skip the first entry.
866 : */
867 0 : return mas_find(&vmi->mas, ULONG_MAX);
868 : }
869 :
870 : static inline
871 : struct vm_area_struct *vma_iter_next_range(struct vma_iterator *vmi)
872 : {
873 0 : return mas_next_range(&vmi->mas, ULONG_MAX);
874 : }
875 :
876 :
877 : static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi)
878 : {
879 0 : return mas_prev(&vmi->mas, 0);
880 : }
881 :
882 : static inline
883 : struct vm_area_struct *vma_iter_prev_range(struct vma_iterator *vmi)
884 : {
885 : return mas_prev_range(&vmi->mas, 0);
886 : }
887 :
888 : static inline unsigned long vma_iter_addr(struct vma_iterator *vmi)
889 : {
890 : return vmi->mas.index;
891 : }
892 :
893 : static inline unsigned long vma_iter_end(struct vma_iterator *vmi)
894 : {
895 0 : return vmi->mas.last + 1;
896 : }
897 : static inline int vma_iter_bulk_alloc(struct vma_iterator *vmi,
898 : unsigned long count)
899 : {
900 0 : return mas_expected_entries(&vmi->mas, count);
901 : }
902 :
903 : /* Free any unused preallocations */
904 : static inline void vma_iter_free(struct vma_iterator *vmi)
905 : {
906 0 : mas_destroy(&vmi->mas);
907 : }
908 :
909 0 : static inline int vma_iter_bulk_store(struct vma_iterator *vmi,
910 : struct vm_area_struct *vma)
911 : {
912 0 : vmi->mas.index = vma->vm_start;
913 0 : vmi->mas.last = vma->vm_end - 1;
914 0 : mas_store(&vmi->mas, vma);
915 0 : if (unlikely(mas_is_err(&vmi->mas)))
916 : return -ENOMEM;
917 :
918 0 : return 0;
919 : }
920 :
921 : static inline void vma_iter_invalidate(struct vma_iterator *vmi)
922 : {
923 0 : mas_pause(&vmi->mas);
924 : }
925 :
926 : static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr)
927 : {
928 0 : mas_set(&vmi->mas, addr);
929 : }
930 :
931 : #define for_each_vma(__vmi, __vma) \
932 : while (((__vma) = vma_next(&(__vmi))) != NULL)
933 :
934 : /* The MM code likes to work with exclusive end addresses */
935 : #define for_each_vma_range(__vmi, __vma, __end) \
936 : while (((__vma) = vma_find(&(__vmi), (__end))) != NULL)
937 :
938 : #ifdef CONFIG_SHMEM
939 : /*
940 : * The vma_is_shmem is not inline because it is used only by slow
941 : * paths in userfault.
942 : */
943 : bool vma_is_shmem(struct vm_area_struct *vma);
944 : bool vma_is_anon_shmem(struct vm_area_struct *vma);
945 : #else
946 : static inline bool vma_is_shmem(struct vm_area_struct *vma) { return false; }
947 : static inline bool vma_is_anon_shmem(struct vm_area_struct *vma) { return false; }
948 : #endif
949 :
950 : int vma_is_stack_for_current(struct vm_area_struct *vma);
951 :
952 : /* flush_tlb_range() takes a vma, not a mm, and can care about flags */
953 : #define TLB_FLUSH_VMA(mm,flags) { .vm_mm = (mm), .vm_flags = (flags) }
954 :
955 : struct mmu_gather;
956 : struct inode;
957 :
958 : /*
959 : * compound_order() can be called without holding a reference, which means
960 : * that niceties like page_folio() don't work. These callers should be
961 : * prepared to handle wild return values. For example, PG_head may be
962 : * set before _folio_order is initialised, or this may be a tail page.
963 : * See compaction.c for some good examples.
964 : */
965 : static inline unsigned int compound_order(struct page *page)
966 : {
967 0 : struct folio *folio = (struct folio *)page;
968 :
969 0 : if (!test_bit(PG_head, &folio->flags))
970 : return 0;
971 0 : return folio->_folio_order;
972 : }
973 :
974 : /**
975 : * folio_order - The allocation order of a folio.
976 : * @folio: The folio.
977 : *
978 : * A folio is composed of 2^order pages. See get_order() for the definition
979 : * of order.
980 : *
981 : * Return: The order of the folio.
982 : */
983 : static inline unsigned int folio_order(struct folio *folio)
984 : {
985 0 : if (!folio_test_large(folio))
986 : return 0;
987 0 : return folio->_folio_order;
988 : }
989 :
990 : #include <linux/huge_mm.h>
991 :
992 : /*
993 : * Methods to modify the page usage count.
994 : *
995 : * What counts for a page usage:
996 : * - cache mapping (page->mapping)
997 : * - private data (page->private)
998 : * - page mapped in a task's page tables, each mapping
999 : * is counted separately
1000 : *
1001 : * Also, many kernel routines increase the page count before a critical
1002 : * routine so they can be sure the page doesn't go away from under them.
1003 : */
1004 :
1005 : /*
1006 : * Drop a ref, return true if the refcount fell to zero (the page has no users)
1007 : */
1008 : static inline int put_page_testzero(struct page *page)
1009 : {
1010 : VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
1011 0 : return page_ref_dec_and_test(page);
1012 : }
1013 :
1014 : static inline int folio_put_testzero(struct folio *folio)
1015 : {
1016 0 : return put_page_testzero(&folio->page);
1017 : }
1018 :
1019 : /*
1020 : * Try to grab a ref unless the page has a refcount of zero, return false if
1021 : * that is the case.
1022 : * This can be called when MMU is off so it must not access
1023 : * any of the virtual mappings.
1024 : */
1025 : static inline bool get_page_unless_zero(struct page *page)
1026 : {
1027 0 : return page_ref_add_unless(page, 1, 0);
1028 : }
1029 :
1030 : static inline struct folio *folio_get_nontail_page(struct page *page)
1031 : {
1032 0 : if (unlikely(!get_page_unless_zero(page)))
1033 : return NULL;
1034 : return (struct folio *)page;
1035 : }
1036 :
1037 : extern int page_is_ram(unsigned long pfn);
1038 :
1039 : enum {
1040 : REGION_INTERSECTS,
1041 : REGION_DISJOINT,
1042 : REGION_MIXED,
1043 : };
1044 :
1045 : int region_intersects(resource_size_t offset, size_t size, unsigned long flags,
1046 : unsigned long desc);
1047 :
1048 : /* Support for virtually mapped pages */
1049 : struct page *vmalloc_to_page(const void *addr);
1050 : unsigned long vmalloc_to_pfn(const void *addr);
1051 :
1052 : /*
1053 : * Determine if an address is within the vmalloc range
1054 : *
1055 : * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
1056 : * is no special casing required.
1057 : */
1058 :
1059 : #ifndef is_ioremap_addr
1060 : #define is_ioremap_addr(x) is_vmalloc_addr(x)
1061 : #endif
1062 :
1063 : #ifdef CONFIG_MMU
1064 : extern bool is_vmalloc_addr(const void *x);
1065 : extern int is_vmalloc_or_module_addr(const void *x);
1066 : #else
1067 : static inline bool is_vmalloc_addr(const void *x)
1068 : {
1069 : return false;
1070 : }
1071 : static inline int is_vmalloc_or_module_addr(const void *x)
1072 : {
1073 : return 0;
1074 : }
1075 : #endif
1076 :
1077 : /*
1078 : * How many times the entire folio is mapped as a single unit (eg by a
1079 : * PMD or PUD entry). This is probably not what you want, except for
1080 : * debugging purposes - it does not include PTE-mapped sub-pages; look
1081 : * at folio_mapcount() or page_mapcount() or total_mapcount() instead.
1082 : */
1083 : static inline int folio_entire_mapcount(struct folio *folio)
1084 : {
1085 : VM_BUG_ON_FOLIO(!folio_test_large(folio), folio);
1086 0 : return atomic_read(&folio->_entire_mapcount) + 1;
1087 : }
1088 :
1089 : /*
1090 : * The atomic page->_mapcount, starts from -1: so that transitions
1091 : * both from it and to it can be tracked, using atomic_inc_and_test
1092 : * and atomic_add_negative(-1).
1093 : */
1094 : static inline void page_mapcount_reset(struct page *page)
1095 : {
1096 530894 : atomic_set(&(page)->_mapcount, -1);
1097 : }
1098 :
1099 : /**
1100 : * page_mapcount() - Number of times this precise page is mapped.
1101 : * @page: The page.
1102 : *
1103 : * The number of times this page is mapped. If this page is part of
1104 : * a large folio, it includes the number of times this page is mapped
1105 : * as part of that folio.
1106 : *
1107 : * The result is undefined for pages which cannot be mapped into userspace.
1108 : * For example SLAB or special types of pages. See function page_has_type().
1109 : * They use this field in struct page differently.
1110 : */
1111 0 : static inline int page_mapcount(struct page *page)
1112 : {
1113 0 : int mapcount = atomic_read(&page->_mapcount) + 1;
1114 :
1115 0 : if (unlikely(PageCompound(page)))
1116 0 : mapcount += folio_entire_mapcount(page_folio(page));
1117 :
1118 0 : return mapcount;
1119 : }
1120 :
1121 : int folio_total_mapcount(struct folio *folio);
1122 :
1123 : /**
1124 : * folio_mapcount() - Calculate the number of mappings of this folio.
1125 : * @folio: The folio.
1126 : *
1127 : * A large folio tracks both how many times the entire folio is mapped,
1128 : * and how many times each individual page in the folio is mapped.
1129 : * This function calculates the total number of times the folio is
1130 : * mapped.
1131 : *
1132 : * Return: The number of times this folio is mapped.
1133 : */
1134 : static inline int folio_mapcount(struct folio *folio)
1135 : {
1136 0 : if (likely(!folio_test_large(folio)))
1137 0 : return atomic_read(&folio->_mapcount) + 1;
1138 0 : return folio_total_mapcount(folio);
1139 : }
1140 :
1141 : static inline int total_mapcount(struct page *page)
1142 : {
1143 : if (likely(!PageCompound(page)))
1144 : return atomic_read(&page->_mapcount) + 1;
1145 : return folio_total_mapcount(page_folio(page));
1146 : }
1147 :
1148 : static inline bool folio_large_is_mapped(struct folio *folio)
1149 : {
1150 : /*
1151 : * Reading _entire_mapcount below could be omitted if hugetlb
1152 : * participated in incrementing nr_pages_mapped when compound mapped.
1153 : */
1154 0 : return atomic_read(&folio->_nr_pages_mapped) > 0 ||
1155 0 : atomic_read(&folio->_entire_mapcount) >= 0;
1156 : }
1157 :
1158 : /**
1159 : * folio_mapped - Is this folio mapped into userspace?
1160 : * @folio: The folio.
1161 : *
1162 : * Return: True if any page in this folio is referenced by user page tables.
1163 : */
1164 : static inline bool folio_mapped(struct folio *folio)
1165 : {
1166 0 : if (likely(!folio_test_large(folio)))
1167 0 : return atomic_read(&folio->_mapcount) >= 0;
1168 0 : return folio_large_is_mapped(folio);
1169 : }
1170 :
1171 : /*
1172 : * Return true if this page is mapped into pagetables.
1173 : * For compound page it returns true if any sub-page of compound page is mapped,
1174 : * even if this particular sub-page is not itself mapped by any PTE or PMD.
1175 : */
1176 0 : static inline bool page_mapped(struct page *page)
1177 : {
1178 0 : if (likely(!PageCompound(page)))
1179 0 : return atomic_read(&page->_mapcount) >= 0;
1180 0 : return folio_large_is_mapped(page_folio(page));
1181 : }
1182 :
1183 : static inline struct page *virt_to_head_page(const void *x)
1184 : {
1185 0 : struct page *page = virt_to_page(x);
1186 :
1187 0 : return compound_head(page);
1188 : }
1189 :
1190 : static inline struct folio *virt_to_folio(const void *x)
1191 : {
1192 15314 : struct page *page = virt_to_page(x);
1193 :
1194 7657 : return page_folio(page);
1195 : }
1196 :
1197 : void __folio_put(struct folio *folio);
1198 :
1199 : void put_pages_list(struct list_head *pages);
1200 :
1201 : void split_page(struct page *page, unsigned int order);
1202 : void folio_copy(struct folio *dst, struct folio *src);
1203 :
1204 : unsigned long nr_free_buffer_pages(void);
1205 :
1206 : /*
1207 : * Compound pages have a destructor function. Provide a
1208 : * prototype for that function and accessor functions.
1209 : * These are _only_ valid on the head of a compound page.
1210 : */
1211 : typedef void compound_page_dtor(struct page *);
1212 :
1213 : /* Keep the enum in sync with compound_page_dtors array in mm/page_alloc.c */
1214 : enum compound_dtor_id {
1215 : NULL_COMPOUND_DTOR,
1216 : COMPOUND_PAGE_DTOR,
1217 : #ifdef CONFIG_HUGETLB_PAGE
1218 : HUGETLB_PAGE_DTOR,
1219 : #endif
1220 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1221 : TRANSHUGE_PAGE_DTOR,
1222 : #endif
1223 : NR_COMPOUND_DTORS,
1224 : };
1225 :
1226 : static inline void folio_set_compound_dtor(struct folio *folio,
1227 : enum compound_dtor_id compound_dtor)
1228 : {
1229 : VM_BUG_ON_FOLIO(compound_dtor >= NR_COMPOUND_DTORS, folio);
1230 96 : folio->_folio_dtor = compound_dtor;
1231 : }
1232 :
1233 : void destroy_large_folio(struct folio *folio);
1234 :
1235 : /* Returns the number of bytes in this potentially compound page. */
1236 : static inline unsigned long page_size(struct page *page)
1237 : {
1238 0 : return PAGE_SIZE << compound_order(page);
1239 : }
1240 :
1241 : /* Returns the number of bits needed for the number of bytes in a page */
1242 : static inline unsigned int page_shift(struct page *page)
1243 : {
1244 : return PAGE_SHIFT + compound_order(page);
1245 : }
1246 :
1247 : /**
1248 : * thp_order - Order of a transparent huge page.
1249 : * @page: Head page of a transparent huge page.
1250 : */
1251 : static inline unsigned int thp_order(struct page *page)
1252 : {
1253 : VM_BUG_ON_PGFLAGS(PageTail(page), page);
1254 0 : return compound_order(page);
1255 : }
1256 :
1257 : /**
1258 : * thp_size - Size of a transparent huge page.
1259 : * @page: Head page of a transparent huge page.
1260 : *
1261 : * Return: Number of bytes in this page.
1262 : */
1263 : static inline unsigned long thp_size(struct page *page)
1264 : {
1265 0 : return PAGE_SIZE << thp_order(page);
1266 : }
1267 :
1268 : void free_compound_page(struct page *page);
1269 :
1270 : #ifdef CONFIG_MMU
1271 : /*
1272 : * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when
1273 : * servicing faults for write access. In the normal case, do always want
1274 : * pte_mkwrite. But get_user_pages can cause write faults for mappings
1275 : * that do not have writing enabled, when used by access_process_vm.
1276 : */
1277 : static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
1278 : {
1279 0 : if (likely(vma->vm_flags & VM_WRITE))
1280 : pte = pte_mkwrite(pte);
1281 : return pte;
1282 : }
1283 :
1284 : vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page);
1285 : void do_set_pte(struct vm_fault *vmf, struct page *page, unsigned long addr);
1286 :
1287 : vm_fault_t finish_fault(struct vm_fault *vmf);
1288 : vm_fault_t finish_mkwrite_fault(struct vm_fault *vmf);
1289 : #endif
1290 :
1291 : /*
1292 : * Multiple processes may "see" the same page. E.g. for untouched
1293 : * mappings of /dev/null, all processes see the same page full of
1294 : * zeroes, and text pages of executables and shared libraries have
1295 : * only one copy in memory, at most, normally.
1296 : *
1297 : * For the non-reserved pages, page_count(page) denotes a reference count.
1298 : * page_count() == 0 means the page is free. page->lru is then used for
1299 : * freelist management in the buddy allocator.
1300 : * page_count() > 0 means the page has been allocated.
1301 : *
1302 : * Pages are allocated by the slab allocator in order to provide memory
1303 : * to kmalloc and kmem_cache_alloc. In this case, the management of the
1304 : * page, and the fields in 'struct page' are the responsibility of mm/slab.c
1305 : * unless a particular usage is carefully commented. (the responsibility of
1306 : * freeing the kmalloc memory is the caller's, of course).
1307 : *
1308 : * A page may be used by anyone else who does a __get_free_page().
1309 : * In this case, page_count still tracks the references, and should only
1310 : * be used through the normal accessor functions. The top bits of page->flags
1311 : * and page->virtual store page management information, but all other fields
1312 : * are unused and could be used privately, carefully. The management of this
1313 : * page is the responsibility of the one who allocated it, and those who have
1314 : * subsequently been given references to it.
1315 : *
1316 : * The other pages (we may call them "pagecache pages") are completely
1317 : * managed by the Linux memory manager: I/O, buffers, swapping etc.
1318 : * The following discussion applies only to them.
1319 : *
1320 : * A pagecache page contains an opaque `private' member, which belongs to the
1321 : * page's address_space. Usually, this is the address of a circular list of
1322 : * the page's disk buffers. PG_private must be set to tell the VM to call
1323 : * into the filesystem to release these pages.
1324 : *
1325 : * A page may belong to an inode's memory mapping. In this case, page->mapping
1326 : * is the pointer to the inode, and page->index is the file offset of the page,
1327 : * in units of PAGE_SIZE.
1328 : *
1329 : * If pagecache pages are not associated with an inode, they are said to be
1330 : * anonymous pages. These may become associated with the swapcache, and in that
1331 : * case PG_swapcache is set, and page->private is an offset into the swapcache.
1332 : *
1333 : * In either case (swapcache or inode backed), the pagecache itself holds one
1334 : * reference to the page. Setting PG_private should also increment the
1335 : * refcount. The each user mapping also has a reference to the page.
1336 : *
1337 : * The pagecache pages are stored in a per-mapping radix tree, which is
1338 : * rooted at mapping->i_pages, and indexed by offset.
1339 : * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
1340 : * lists, we instead now tag pages as dirty/writeback in the radix tree.
1341 : *
1342 : * All pagecache pages may be subject to I/O:
1343 : * - inode pages may need to be read from disk,
1344 : * - inode pages which have been modified and are MAP_SHARED may need
1345 : * to be written back to the inode on disk,
1346 : * - anonymous pages (including MAP_PRIVATE file mappings) which have been
1347 : * modified may need to be swapped out to swap space and (later) to be read
1348 : * back into memory.
1349 : */
1350 :
1351 : #if defined(CONFIG_ZONE_DEVICE) && defined(CONFIG_FS_DAX)
1352 : DECLARE_STATIC_KEY_FALSE(devmap_managed_key);
1353 :
1354 : bool __put_devmap_managed_page_refs(struct page *page, int refs);
1355 : static inline bool put_devmap_managed_page_refs(struct page *page, int refs)
1356 : {
1357 : if (!static_branch_unlikely(&devmap_managed_key))
1358 : return false;
1359 : if (!is_zone_device_page(page))
1360 : return false;
1361 : return __put_devmap_managed_page_refs(page, refs);
1362 : }
1363 : #else /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
1364 : static inline bool put_devmap_managed_page_refs(struct page *page, int refs)
1365 : {
1366 : return false;
1367 : }
1368 : #endif /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
1369 :
1370 : static inline bool put_devmap_managed_page(struct page *page)
1371 : {
1372 0 : return put_devmap_managed_page_refs(page, 1);
1373 : }
1374 :
1375 : /* 127: arbitrary random number, small enough to assemble well */
1376 : #define folio_ref_zero_or_close_to_overflow(folio) \
1377 : ((unsigned int) folio_ref_count(folio) + 127u <= 127u)
1378 :
1379 : /**
1380 : * folio_get - Increment the reference count on a folio.
1381 : * @folio: The folio.
1382 : *
1383 : * Context: May be called in any context, as long as you know that
1384 : * you have a refcount on the folio. If you do not already have one,
1385 : * folio_try_get() may be the right interface for you to use.
1386 : */
1387 : static inline void folio_get(struct folio *folio)
1388 : {
1389 : VM_BUG_ON_FOLIO(folio_ref_zero_or_close_to_overflow(folio), folio);
1390 0 : folio_ref_inc(folio);
1391 : }
1392 :
1393 : static inline void get_page(struct page *page)
1394 : {
1395 0 : folio_get(page_folio(page));
1396 : }
1397 :
1398 0 : static inline __must_check bool try_get_page(struct page *page)
1399 : {
1400 0 : page = compound_head(page);
1401 0 : if (WARN_ON_ONCE(page_ref_count(page) <= 0))
1402 : return false;
1403 0 : page_ref_inc(page);
1404 0 : return true;
1405 : }
1406 :
1407 : /**
1408 : * folio_put - Decrement the reference count on a folio.
1409 : * @folio: The folio.
1410 : *
1411 : * If the folio's reference count reaches zero, the memory will be
1412 : * released back to the page allocator and may be used by another
1413 : * allocation immediately. Do not access the memory or the struct folio
1414 : * after calling folio_put() unless you can be sure that it wasn't the
1415 : * last reference.
1416 : *
1417 : * Context: May be called in process or interrupt context, but not in NMI
1418 : * context. May be called while holding a spinlock.
1419 : */
1420 : static inline void folio_put(struct folio *folio)
1421 : {
1422 0 : if (folio_put_testzero(folio))
1423 0 : __folio_put(folio);
1424 : }
1425 :
1426 : /**
1427 : * folio_put_refs - Reduce the reference count on a folio.
1428 : * @folio: The folio.
1429 : * @refs: The amount to subtract from the folio's reference count.
1430 : *
1431 : * If the folio's reference count reaches zero, the memory will be
1432 : * released back to the page allocator and may be used by another
1433 : * allocation immediately. Do not access the memory or the struct folio
1434 : * after calling folio_put_refs() unless you can be sure that these weren't
1435 : * the last references.
1436 : *
1437 : * Context: May be called in process or interrupt context, but not in NMI
1438 : * context. May be called while holding a spinlock.
1439 : */
1440 : static inline void folio_put_refs(struct folio *folio, int refs)
1441 : {
1442 0 : if (folio_ref_sub_and_test(folio, refs))
1443 0 : __folio_put(folio);
1444 : }
1445 :
1446 : /*
1447 : * union release_pages_arg - an array of pages or folios
1448 : *
1449 : * release_pages() releases a simple array of multiple pages, and
1450 : * accepts various different forms of said page array: either
1451 : * a regular old boring array of pages, an array of folios, or
1452 : * an array of encoded page pointers.
1453 : *
1454 : * The transparent union syntax for this kind of "any of these
1455 : * argument types" is all kinds of ugly, so look away.
1456 : */
1457 : typedef union {
1458 : struct page **pages;
1459 : struct folio **folios;
1460 : struct encoded_page **encoded_pages;
1461 : } release_pages_arg __attribute__ ((__transparent_union__));
1462 :
1463 : void release_pages(release_pages_arg, int nr);
1464 :
1465 : /**
1466 : * folios_put - Decrement the reference count on an array of folios.
1467 : * @folios: The folios.
1468 : * @nr: How many folios there are.
1469 : *
1470 : * Like folio_put(), but for an array of folios. This is more efficient
1471 : * than writing the loop yourself as it will optimise the locks which
1472 : * need to be taken if the folios are freed.
1473 : *
1474 : * Context: May be called in process or interrupt context, but not in NMI
1475 : * context. May be called while holding a spinlock.
1476 : */
1477 : static inline void folios_put(struct folio **folios, unsigned int nr)
1478 : {
1479 0 : release_pages(folios, nr);
1480 : }
1481 :
1482 0 : static inline void put_page(struct page *page)
1483 : {
1484 0 : struct folio *folio = page_folio(page);
1485 :
1486 : /*
1487 : * For some devmap managed pages we need to catch refcount transition
1488 : * from 2 to 1:
1489 : */
1490 0 : if (put_devmap_managed_page(&folio->page))
1491 : return;
1492 : folio_put(folio);
1493 : }
1494 :
1495 : /*
1496 : * GUP_PIN_COUNTING_BIAS, and the associated functions that use it, overload
1497 : * the page's refcount so that two separate items are tracked: the original page
1498 : * reference count, and also a new count of how many pin_user_pages() calls were
1499 : * made against the page. ("gup-pinned" is another term for the latter).
1500 : *
1501 : * With this scheme, pin_user_pages() becomes special: such pages are marked as
1502 : * distinct from normal pages. As such, the unpin_user_page() call (and its
1503 : * variants) must be used in order to release gup-pinned pages.
1504 : *
1505 : * Choice of value:
1506 : *
1507 : * By making GUP_PIN_COUNTING_BIAS a power of two, debugging of page reference
1508 : * counts with respect to pin_user_pages() and unpin_user_page() becomes
1509 : * simpler, due to the fact that adding an even power of two to the page
1510 : * refcount has the effect of using only the upper N bits, for the code that
1511 : * counts up using the bias value. This means that the lower bits are left for
1512 : * the exclusive use of the original code that increments and decrements by one
1513 : * (or at least, by much smaller values than the bias value).
1514 : *
1515 : * Of course, once the lower bits overflow into the upper bits (and this is
1516 : * OK, because subtraction recovers the original values), then visual inspection
1517 : * no longer suffices to directly view the separate counts. However, for normal
1518 : * applications that don't have huge page reference counts, this won't be an
1519 : * issue.
1520 : *
1521 : * Locking: the lockless algorithm described in folio_try_get_rcu()
1522 : * provides safe operation for get_user_pages(), page_mkclean() and
1523 : * other calls that race to set up page table entries.
1524 : */
1525 : #define GUP_PIN_COUNTING_BIAS (1U << 10)
1526 :
1527 : void unpin_user_page(struct page *page);
1528 : void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages,
1529 : bool make_dirty);
1530 : void unpin_user_page_range_dirty_lock(struct page *page, unsigned long npages,
1531 : bool make_dirty);
1532 : void unpin_user_pages(struct page **pages, unsigned long npages);
1533 :
1534 : static inline bool is_cow_mapping(vm_flags_t flags)
1535 : {
1536 0 : return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
1537 : }
1538 :
1539 : #ifndef CONFIG_MMU
1540 : static inline bool is_nommu_shared_mapping(vm_flags_t flags)
1541 : {
1542 : /*
1543 : * NOMMU shared mappings are ordinary MAP_SHARED mappings and selected
1544 : * R/O MAP_PRIVATE file mappings that are an effective R/O overlay of
1545 : * a file mapping. R/O MAP_PRIVATE mappings might still modify
1546 : * underlying memory if ptrace is active, so this is only possible if
1547 : * ptrace does not apply. Note that there is no mprotect() to upgrade
1548 : * write permissions later.
1549 : */
1550 : return flags & (VM_MAYSHARE | VM_MAYOVERLAY);
1551 : }
1552 : #endif
1553 :
1554 : #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
1555 : #define SECTION_IN_PAGE_FLAGS
1556 : #endif
1557 :
1558 : /*
1559 : * The identification function is mainly used by the buddy allocator for
1560 : * determining if two pages could be buddies. We are not really identifying
1561 : * the zone since we could be using the section number id if we do not have
1562 : * node id available in page flags.
1563 : * We only guarantee that it will return the same value for two combinable
1564 : * pages in a zone.
1565 : */
1566 : static inline int page_zone_id(struct page *page)
1567 : {
1568 520 : return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK;
1569 : }
1570 :
1571 : #ifdef NODE_NOT_IN_PAGE_FLAGS
1572 : extern int page_to_nid(const struct page *page);
1573 : #else
1574 : static inline int page_to_nid(const struct page *page)
1575 : {
1576 4075 : struct page *p = (struct page *)page;
1577 :
1578 : return (PF_POISONED_CHECK(p)->flags >> NODES_PGSHIFT) & NODES_MASK;
1579 : }
1580 : #endif
1581 :
1582 : static inline int folio_nid(const struct folio *folio)
1583 : {
1584 475 : return page_to_nid(&folio->page);
1585 : }
1586 :
1587 : #ifdef CONFIG_NUMA_BALANCING
1588 : /* page access time bits needs to hold at least 4 seconds */
1589 : #define PAGE_ACCESS_TIME_MIN_BITS 12
1590 : #if LAST_CPUPID_SHIFT < PAGE_ACCESS_TIME_MIN_BITS
1591 : #define PAGE_ACCESS_TIME_BUCKETS \
1592 : (PAGE_ACCESS_TIME_MIN_BITS - LAST_CPUPID_SHIFT)
1593 : #else
1594 : #define PAGE_ACCESS_TIME_BUCKETS 0
1595 : #endif
1596 :
1597 : #define PAGE_ACCESS_TIME_MASK \
1598 : (LAST_CPUPID_MASK << PAGE_ACCESS_TIME_BUCKETS)
1599 :
1600 : static inline int cpu_pid_to_cpupid(int cpu, int pid)
1601 : {
1602 : return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK);
1603 : }
1604 :
1605 : static inline int cpupid_to_pid(int cpupid)
1606 : {
1607 : return cpupid & LAST__PID_MASK;
1608 : }
1609 :
1610 : static inline int cpupid_to_cpu(int cpupid)
1611 : {
1612 : return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK;
1613 : }
1614 :
1615 : static inline int cpupid_to_nid(int cpupid)
1616 : {
1617 : return cpu_to_node(cpupid_to_cpu(cpupid));
1618 : }
1619 :
1620 : static inline bool cpupid_pid_unset(int cpupid)
1621 : {
1622 : return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK);
1623 : }
1624 :
1625 : static inline bool cpupid_cpu_unset(int cpupid)
1626 : {
1627 : return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK);
1628 : }
1629 :
1630 : static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid)
1631 : {
1632 : return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid);
1633 : }
1634 :
1635 : #define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid)
1636 : #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
1637 : static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1638 : {
1639 : return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK);
1640 : }
1641 :
1642 : static inline int page_cpupid_last(struct page *page)
1643 : {
1644 : return page->_last_cpupid;
1645 : }
1646 : static inline void page_cpupid_reset_last(struct page *page)
1647 : {
1648 : page->_last_cpupid = -1 & LAST_CPUPID_MASK;
1649 : }
1650 : #else
1651 : static inline int page_cpupid_last(struct page *page)
1652 : {
1653 : return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
1654 : }
1655 :
1656 : extern int page_cpupid_xchg_last(struct page *page, int cpupid);
1657 :
1658 : static inline void page_cpupid_reset_last(struct page *page)
1659 : {
1660 : page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT;
1661 : }
1662 : #endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
1663 :
1664 : static inline int xchg_page_access_time(struct page *page, int time)
1665 : {
1666 : int last_time;
1667 :
1668 : last_time = page_cpupid_xchg_last(page, time >> PAGE_ACCESS_TIME_BUCKETS);
1669 : return last_time << PAGE_ACCESS_TIME_BUCKETS;
1670 : }
1671 :
1672 : static inline void vma_set_access_pid_bit(struct vm_area_struct *vma)
1673 : {
1674 : unsigned int pid_bit;
1675 :
1676 : pid_bit = hash_32(current->pid, ilog2(BITS_PER_LONG));
1677 : if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->access_pids[1])) {
1678 : __set_bit(pid_bit, &vma->numab_state->access_pids[1]);
1679 : }
1680 : }
1681 : #else /* !CONFIG_NUMA_BALANCING */
1682 : static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1683 : {
1684 0 : return page_to_nid(page); /* XXX */
1685 : }
1686 :
1687 : static inline int xchg_page_access_time(struct page *page, int time)
1688 : {
1689 : return 0;
1690 : }
1691 :
1692 : static inline int page_cpupid_last(struct page *page)
1693 : {
1694 : return page_to_nid(page); /* XXX */
1695 : }
1696 :
1697 : static inline int cpupid_to_nid(int cpupid)
1698 : {
1699 : return -1;
1700 : }
1701 :
1702 : static inline int cpupid_to_pid(int cpupid)
1703 : {
1704 : return -1;
1705 : }
1706 :
1707 : static inline int cpupid_to_cpu(int cpupid)
1708 : {
1709 : return -1;
1710 : }
1711 :
1712 : static inline int cpu_pid_to_cpupid(int nid, int pid)
1713 : {
1714 : return -1;
1715 : }
1716 :
1717 : static inline bool cpupid_pid_unset(int cpupid)
1718 : {
1719 : return true;
1720 : }
1721 :
1722 : static inline void page_cpupid_reset_last(struct page *page)
1723 : {
1724 : }
1725 :
1726 : static inline bool cpupid_match_pid(struct task_struct *task, int cpupid)
1727 : {
1728 : return false;
1729 : }
1730 :
1731 : static inline void vma_set_access_pid_bit(struct vm_area_struct *vma)
1732 : {
1733 : }
1734 : #endif /* CONFIG_NUMA_BALANCING */
1735 :
1736 : #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
1737 :
1738 : /*
1739 : * KASAN per-page tags are stored xor'ed with 0xff. This allows to avoid
1740 : * setting tags for all pages to native kernel tag value 0xff, as the default
1741 : * value 0x00 maps to 0xff.
1742 : */
1743 :
1744 : static inline u8 page_kasan_tag(const struct page *page)
1745 : {
1746 : u8 tag = 0xff;
1747 :
1748 : if (kasan_enabled()) {
1749 : tag = (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK;
1750 : tag ^= 0xff;
1751 : }
1752 :
1753 : return tag;
1754 : }
1755 :
1756 : static inline void page_kasan_tag_set(struct page *page, u8 tag)
1757 : {
1758 : unsigned long old_flags, flags;
1759 :
1760 : if (!kasan_enabled())
1761 : return;
1762 :
1763 : tag ^= 0xff;
1764 : old_flags = READ_ONCE(page->flags);
1765 : do {
1766 : flags = old_flags;
1767 : flags &= ~(KASAN_TAG_MASK << KASAN_TAG_PGSHIFT);
1768 : flags |= (tag & KASAN_TAG_MASK) << KASAN_TAG_PGSHIFT;
1769 : } while (unlikely(!try_cmpxchg(&page->flags, &old_flags, flags)));
1770 : }
1771 :
1772 : static inline void page_kasan_tag_reset(struct page *page)
1773 : {
1774 : if (kasan_enabled())
1775 : page_kasan_tag_set(page, 0xff);
1776 : }
1777 :
1778 : #else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
1779 :
1780 : static inline u8 page_kasan_tag(const struct page *page)
1781 : {
1782 : return 0xff;
1783 : }
1784 :
1785 : static inline void page_kasan_tag_set(struct page *page, u8 tag) { }
1786 : static inline void page_kasan_tag_reset(struct page *page) { }
1787 :
1788 : #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
1789 :
1790 : static inline struct zone *page_zone(const struct page *page)
1791 : {
1792 4167 : return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
1793 : }
1794 :
1795 : static inline pg_data_t *page_pgdat(const struct page *page)
1796 : {
1797 1776 : return NODE_DATA(page_to_nid(page));
1798 : }
1799 :
1800 : static inline struct zone *folio_zone(const struct folio *folio)
1801 : {
1802 0 : return page_zone(&folio->page);
1803 : }
1804 :
1805 : static inline pg_data_t *folio_pgdat(const struct folio *folio)
1806 : {
1807 435 : return page_pgdat(&folio->page);
1808 : }
1809 :
1810 : #ifdef SECTION_IN_PAGE_FLAGS
1811 : static inline void set_page_section(struct page *page, unsigned long section)
1812 : {
1813 : page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
1814 : page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
1815 : }
1816 :
1817 : static inline unsigned long page_to_section(const struct page *page)
1818 : {
1819 : return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
1820 : }
1821 : #endif
1822 :
1823 : /**
1824 : * folio_pfn - Return the Page Frame Number of a folio.
1825 : * @folio: The folio.
1826 : *
1827 : * A folio may contain multiple pages. The pages have consecutive
1828 : * Page Frame Numbers.
1829 : *
1830 : * Return: The Page Frame Number of the first page in the folio.
1831 : */
1832 : static inline unsigned long folio_pfn(struct folio *folio)
1833 : {
1834 0 : return page_to_pfn(&folio->page);
1835 : }
1836 :
1837 : static inline struct folio *pfn_folio(unsigned long pfn)
1838 : {
1839 : return page_folio(pfn_to_page(pfn));
1840 : }
1841 :
1842 : /**
1843 : * folio_maybe_dma_pinned - Report if a folio may be pinned for DMA.
1844 : * @folio: The folio.
1845 : *
1846 : * This function checks if a folio has been pinned via a call to
1847 : * a function in the pin_user_pages() family.
1848 : *
1849 : * For small folios, the return value is partially fuzzy: false is not fuzzy,
1850 : * because it means "definitely not pinned for DMA", but true means "probably
1851 : * pinned for DMA, but possibly a false positive due to having at least
1852 : * GUP_PIN_COUNTING_BIAS worth of normal folio references".
1853 : *
1854 : * False positives are OK, because: a) it's unlikely for a folio to
1855 : * get that many refcounts, and b) all the callers of this routine are
1856 : * expected to be able to deal gracefully with a false positive.
1857 : *
1858 : * For large folios, the result will be exactly correct. That's because
1859 : * we have more tracking data available: the _pincount field is used
1860 : * instead of the GUP_PIN_COUNTING_BIAS scheme.
1861 : *
1862 : * For more information, please see Documentation/core-api/pin_user_pages.rst.
1863 : *
1864 : * Return: True, if it is likely that the page has been "dma-pinned".
1865 : * False, if the page is definitely not dma-pinned.
1866 : */
1867 : static inline bool folio_maybe_dma_pinned(struct folio *folio)
1868 : {
1869 0 : if (folio_test_large(folio))
1870 0 : return atomic_read(&folio->_pincount) > 0;
1871 :
1872 : /*
1873 : * folio_ref_count() is signed. If that refcount overflows, then
1874 : * folio_ref_count() returns a negative value, and callers will avoid
1875 : * further incrementing the refcount.
1876 : *
1877 : * Here, for that overflow case, use the sign bit to count a little
1878 : * bit higher via unsigned math, and thus still get an accurate result.
1879 : */
1880 0 : return ((unsigned int)folio_ref_count(folio)) >=
1881 : GUP_PIN_COUNTING_BIAS;
1882 : }
1883 :
1884 : static inline bool page_maybe_dma_pinned(struct page *page)
1885 : {
1886 0 : return folio_maybe_dma_pinned(page_folio(page));
1887 : }
1888 :
1889 : /*
1890 : * This should most likely only be called during fork() to see whether we
1891 : * should break the cow immediately for an anon page on the src mm.
1892 : *
1893 : * The caller has to hold the PT lock and the vma->vm_mm->->write_protect_seq.
1894 : */
1895 0 : static inline bool page_needs_cow_for_dma(struct vm_area_struct *vma,
1896 : struct page *page)
1897 : {
1898 : VM_BUG_ON(!(raw_read_seqcount(&vma->vm_mm->write_protect_seq) & 1));
1899 :
1900 0 : if (!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))
1901 : return false;
1902 :
1903 : return page_maybe_dma_pinned(page);
1904 : }
1905 :
1906 : /**
1907 : * is_zero_page - Query if a page is a zero page
1908 : * @page: The page to query
1909 : *
1910 : * This returns true if @page is one of the permanent zero pages.
1911 : */
1912 : static inline bool is_zero_page(const struct page *page)
1913 : {
1914 0 : return is_zero_pfn(page_to_pfn(page));
1915 : }
1916 :
1917 : /**
1918 : * is_zero_folio - Query if a folio is a zero page
1919 : * @folio: The folio to query
1920 : *
1921 : * This returns true if @folio is one of the permanent zero pages.
1922 : */
1923 : static inline bool is_zero_folio(const struct folio *folio)
1924 : {
1925 0 : return is_zero_page(&folio->page);
1926 : }
1927 :
1928 : /* MIGRATE_CMA and ZONE_MOVABLE do not allow pin folios */
1929 : #ifdef CONFIG_MIGRATION
1930 : static inline bool folio_is_longterm_pinnable(struct folio *folio)
1931 : {
1932 : #ifdef CONFIG_CMA
1933 : int mt = folio_migratetype(folio);
1934 :
1935 : if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE)
1936 : return false;
1937 : #endif
1938 : /* The zero page can be "pinned" but gets special handling. */
1939 0 : if (is_zero_folio(folio))
1940 : return true;
1941 :
1942 : /* Coherent device memory must always allow eviction. */
1943 0 : if (folio_is_device_coherent(folio))
1944 : return false;
1945 :
1946 : /* Otherwise, non-movable zone folios can be pinned. */
1947 0 : return !folio_is_zone_movable(folio);
1948 :
1949 : }
1950 : #else
1951 : static inline bool folio_is_longterm_pinnable(struct folio *folio)
1952 : {
1953 : return true;
1954 : }
1955 : #endif
1956 :
1957 : static inline void set_page_zone(struct page *page, enum zone_type zone)
1958 : {
1959 : page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
1960 265447 : page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
1961 : }
1962 :
1963 : static inline void set_page_node(struct page *page, unsigned long node)
1964 : {
1965 : page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
1966 : page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
1967 : }
1968 :
1969 : static inline void set_page_links(struct page *page, enum zone_type zone,
1970 : unsigned long node, unsigned long pfn)
1971 : {
1972 530894 : set_page_zone(page, zone);
1973 265447 : set_page_node(page, node);
1974 : #ifdef SECTION_IN_PAGE_FLAGS
1975 : set_page_section(page, pfn_to_section_nr(pfn));
1976 : #endif
1977 : }
1978 :
1979 : /**
1980 : * folio_nr_pages - The number of pages in the folio.
1981 : * @folio: The folio.
1982 : *
1983 : * Return: A positive power of two.
1984 : */
1985 : static inline long folio_nr_pages(struct folio *folio)
1986 : {
1987 0 : if (!folio_test_large(folio))
1988 : return 1;
1989 : #ifdef CONFIG_64BIT
1990 0 : return folio->_folio_nr_pages;
1991 : #else
1992 : return 1L << folio->_folio_order;
1993 : #endif
1994 : }
1995 :
1996 : /*
1997 : * compound_nr() returns the number of pages in this potentially compound
1998 : * page. compound_nr() can be called on a tail page, and is defined to
1999 : * return 1 in that case.
2000 : */
2001 : static inline unsigned long compound_nr(struct page *page)
2002 : {
2003 0 : struct folio *folio = (struct folio *)page;
2004 :
2005 0 : if (!test_bit(PG_head, &folio->flags))
2006 : return 1;
2007 : #ifdef CONFIG_64BIT
2008 0 : return folio->_folio_nr_pages;
2009 : #else
2010 : return 1L << folio->_folio_order;
2011 : #endif
2012 : }
2013 :
2014 : /**
2015 : * thp_nr_pages - The number of regular pages in this huge page.
2016 : * @page: The head page of a huge page.
2017 : */
2018 : static inline int thp_nr_pages(struct page *page)
2019 : {
2020 0 : return folio_nr_pages((struct folio *)page);
2021 : }
2022 :
2023 : /**
2024 : * folio_next - Move to the next physical folio.
2025 : * @folio: The folio we're currently operating on.
2026 : *
2027 : * If you have physically contiguous memory which may span more than
2028 : * one folio (eg a &struct bio_vec), use this function to move from one
2029 : * folio to the next. Do not use it if the memory is only virtually
2030 : * contiguous as the folios are almost certainly not adjacent to each
2031 : * other. This is the folio equivalent to writing ``page++``.
2032 : *
2033 : * Context: We assume that the folios are refcounted and/or locked at a
2034 : * higher level and do not adjust the reference counts.
2035 : * Return: The next struct folio.
2036 : */
2037 : static inline struct folio *folio_next(struct folio *folio)
2038 : {
2039 0 : return (struct folio *)folio_page(folio, folio_nr_pages(folio));
2040 : }
2041 :
2042 : /**
2043 : * folio_shift - The size of the memory described by this folio.
2044 : * @folio: The folio.
2045 : *
2046 : * A folio represents a number of bytes which is a power-of-two in size.
2047 : * This function tells you which power-of-two the folio is. See also
2048 : * folio_size() and folio_order().
2049 : *
2050 : * Context: The caller should have a reference on the folio to prevent
2051 : * it from being split. It is not necessary for the folio to be locked.
2052 : * Return: The base-2 logarithm of the size of this folio.
2053 : */
2054 : static inline unsigned int folio_shift(struct folio *folio)
2055 : {
2056 0 : return PAGE_SHIFT + folio_order(folio);
2057 : }
2058 :
2059 : /**
2060 : * folio_size - The number of bytes in a folio.
2061 : * @folio: The folio.
2062 : *
2063 : * Context: The caller should have a reference on the folio to prevent
2064 : * it from being split. It is not necessary for the folio to be locked.
2065 : * Return: The number of bytes in this folio.
2066 : */
2067 : static inline size_t folio_size(struct folio *folio)
2068 : {
2069 0 : return PAGE_SIZE << folio_order(folio);
2070 : }
2071 :
2072 : /**
2073 : * folio_estimated_sharers - Estimate the number of sharers of a folio.
2074 : * @folio: The folio.
2075 : *
2076 : * folio_estimated_sharers() aims to serve as a function to efficiently
2077 : * estimate the number of processes sharing a folio. This is done by
2078 : * looking at the precise mapcount of the first subpage in the folio, and
2079 : * assuming the other subpages are the same. This may not be true for large
2080 : * folios. If you want exact mapcounts for exact calculations, look at
2081 : * page_mapcount() or folio_total_mapcount().
2082 : *
2083 : * Return: The estimated number of processes sharing a folio.
2084 : */
2085 : static inline int folio_estimated_sharers(struct folio *folio)
2086 : {
2087 : return page_mapcount(folio_page(folio, 0));
2088 : }
2089 :
2090 : #ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE
2091 : static inline int arch_make_page_accessible(struct page *page)
2092 : {
2093 : return 0;
2094 : }
2095 : #endif
2096 :
2097 : #ifndef HAVE_ARCH_MAKE_FOLIO_ACCESSIBLE
2098 : static inline int arch_make_folio_accessible(struct folio *folio)
2099 : {
2100 : int ret;
2101 0 : long i, nr = folio_nr_pages(folio);
2102 :
2103 0 : for (i = 0; i < nr; i++) {
2104 : ret = arch_make_page_accessible(folio_page(folio, i));
2105 : if (ret)
2106 : break;
2107 : }
2108 :
2109 : return ret;
2110 : }
2111 : #endif
2112 :
2113 : /*
2114 : * Some inline functions in vmstat.h depend on page_zone()
2115 : */
2116 : #include <linux/vmstat.h>
2117 :
2118 : static __always_inline void *lowmem_page_address(const struct page *page)
2119 : {
2120 1030 : return page_to_virt(page);
2121 : }
2122 :
2123 : #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
2124 : #define HASHED_PAGE_VIRTUAL
2125 : #endif
2126 :
2127 : #if defined(WANT_PAGE_VIRTUAL)
2128 : static inline void *page_address(const struct page *page)
2129 : {
2130 : return page->virtual;
2131 : }
2132 : static inline void set_page_address(struct page *page, void *address)
2133 : {
2134 : page->virtual = address;
2135 : }
2136 : #define page_address_init() do { } while(0)
2137 : #endif
2138 :
2139 : #if defined(HASHED_PAGE_VIRTUAL)
2140 : void *page_address(const struct page *page);
2141 : void set_page_address(struct page *page, void *virtual);
2142 : void page_address_init(void);
2143 : #endif
2144 :
2145 : #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
2146 : #define page_address(page) lowmem_page_address(page)
2147 : #define set_page_address(page, address) do { } while(0)
2148 : #define page_address_init() do { } while(0)
2149 : #endif
2150 :
2151 : static inline void *folio_address(const struct folio *folio)
2152 : {
2153 870 : return page_address(&folio->page);
2154 : }
2155 :
2156 : extern void *page_rmapping(struct page *page);
2157 : extern pgoff_t __page_file_index(struct page *page);
2158 :
2159 : /*
2160 : * Return the pagecache index of the passed page. Regular pagecache pages
2161 : * use ->index whereas swapcache pages use swp_offset(->private)
2162 : */
2163 0 : static inline pgoff_t page_index(struct page *page)
2164 : {
2165 0 : if (unlikely(PageSwapCache(page)))
2166 0 : return __page_file_index(page);
2167 0 : return page->index;
2168 : }
2169 :
2170 : /*
2171 : * Return true only if the page has been allocated with
2172 : * ALLOC_NO_WATERMARKS and the low watermark was not
2173 : * met implying that the system is under some pressure.
2174 : */
2175 : static inline bool page_is_pfmemalloc(const struct page *page)
2176 : {
2177 : /*
2178 : * lru.next has bit 1 set if the page is allocated from the
2179 : * pfmemalloc reserves. Callers may simply overwrite it if
2180 : * they do not need to preserve that information.
2181 : */
2182 0 : return (uintptr_t)page->lru.next & BIT(1);
2183 : }
2184 :
2185 : /*
2186 : * Return true only if the folio has been allocated with
2187 : * ALLOC_NO_WATERMARKS and the low watermark was not
2188 : * met implying that the system is under some pressure.
2189 : */
2190 : static inline bool folio_is_pfmemalloc(const struct folio *folio)
2191 : {
2192 : /*
2193 : * lru.next has bit 1 set if the page is allocated from the
2194 : * pfmemalloc reserves. Callers may simply overwrite it if
2195 : * they do not need to preserve that information.
2196 : */
2197 435 : return (uintptr_t)folio->lru.next & BIT(1);
2198 : }
2199 :
2200 : /*
2201 : * Only to be called by the page allocator on a freshly allocated
2202 : * page.
2203 : */
2204 : static inline void set_page_pfmemalloc(struct page *page)
2205 : {
2206 0 : page->lru.next = (void *)BIT(1);
2207 : }
2208 :
2209 : static inline void clear_page_pfmemalloc(struct page *page)
2210 : {
2211 505 : page->lru.next = NULL;
2212 : }
2213 :
2214 : /*
2215 : * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
2216 : */
2217 : extern void pagefault_out_of_memory(void);
2218 :
2219 : #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
2220 : #define offset_in_thp(page, p) ((unsigned long)(p) & (thp_size(page) - 1))
2221 : #define offset_in_folio(folio, p) ((unsigned long)(p) & (folio_size(folio) - 1))
2222 :
2223 : /*
2224 : * Flags passed to show_mem() and show_free_areas() to suppress output in
2225 : * various contexts.
2226 : */
2227 : #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */
2228 :
2229 : extern void __show_free_areas(unsigned int flags, nodemask_t *nodemask, int max_zone_idx);
2230 : static void __maybe_unused show_free_areas(unsigned int flags, nodemask_t *nodemask)
2231 : {
2232 : __show_free_areas(flags, nodemask, MAX_NR_ZONES - 1);
2233 : }
2234 :
2235 : /*
2236 : * Parameter block passed down to zap_pte_range in exceptional cases.
2237 : */
2238 : struct zap_details {
2239 : struct folio *single_folio; /* Locked folio to be unmapped */
2240 : bool even_cows; /* Zap COWed private pages too? */
2241 : zap_flags_t zap_flags; /* Extra flags for zapping */
2242 : };
2243 :
2244 : /*
2245 : * Whether to drop the pte markers, for example, the uffd-wp information for
2246 : * file-backed memory. This should only be specified when we will completely
2247 : * drop the page in the mm, either by truncation or unmapping of the vma. By
2248 : * default, the flag is not set.
2249 : */
2250 : #define ZAP_FLAG_DROP_MARKER ((__force zap_flags_t) BIT(0))
2251 : /* Set in unmap_vmas() to indicate a final unmap call. Only used by hugetlb */
2252 : #define ZAP_FLAG_UNMAP ((__force zap_flags_t) BIT(1))
2253 :
2254 : #ifdef CONFIG_SCHED_MM_CID
2255 : void sched_mm_cid_before_execve(struct task_struct *t);
2256 : void sched_mm_cid_after_execve(struct task_struct *t);
2257 : void sched_mm_cid_fork(struct task_struct *t);
2258 : void sched_mm_cid_exit_signals(struct task_struct *t);
2259 : static inline int task_mm_cid(struct task_struct *t)
2260 : {
2261 : return t->mm_cid;
2262 : }
2263 : #else
2264 : static inline void sched_mm_cid_before_execve(struct task_struct *t) { }
2265 : static inline void sched_mm_cid_after_execve(struct task_struct *t) { }
2266 : static inline void sched_mm_cid_fork(struct task_struct *t) { }
2267 : static inline void sched_mm_cid_exit_signals(struct task_struct *t) { }
2268 : static inline int task_mm_cid(struct task_struct *t)
2269 : {
2270 : /*
2271 : * Use the processor id as a fall-back when the mm cid feature is
2272 : * disabled. This provides functional per-cpu data structure accesses
2273 : * in user-space, althrough it won't provide the memory usage benefits.
2274 : */
2275 : return raw_smp_processor_id();
2276 : }
2277 : #endif
2278 :
2279 : #ifdef CONFIG_MMU
2280 : extern bool can_do_mlock(void);
2281 : #else
2282 : static inline bool can_do_mlock(void) { return false; }
2283 : #endif
2284 : extern int user_shm_lock(size_t, struct ucounts *);
2285 : extern void user_shm_unlock(size_t, struct ucounts *);
2286 :
2287 : struct folio *vm_normal_folio(struct vm_area_struct *vma, unsigned long addr,
2288 : pte_t pte);
2289 : struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
2290 : pte_t pte);
2291 : struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
2292 : pmd_t pmd);
2293 :
2294 : void zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
2295 : unsigned long size);
2296 : void zap_page_range_single(struct vm_area_struct *vma, unsigned long address,
2297 : unsigned long size, struct zap_details *details);
2298 : static inline void zap_vma_pages(struct vm_area_struct *vma)
2299 : {
2300 : zap_page_range_single(vma, vma->vm_start,
2301 : vma->vm_end - vma->vm_start, NULL);
2302 : }
2303 : void unmap_vmas(struct mmu_gather *tlb, struct maple_tree *mt,
2304 : struct vm_area_struct *start_vma, unsigned long start,
2305 : unsigned long end, bool mm_wr_locked);
2306 :
2307 : struct mmu_notifier_range;
2308 :
2309 : void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
2310 : unsigned long end, unsigned long floor, unsigned long ceiling);
2311 : int
2312 : copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma);
2313 : int follow_pte(struct mm_struct *mm, unsigned long address,
2314 : pte_t **ptepp, spinlock_t **ptlp);
2315 : int follow_pfn(struct vm_area_struct *vma, unsigned long address,
2316 : unsigned long *pfn);
2317 : int follow_phys(struct vm_area_struct *vma, unsigned long address,
2318 : unsigned int flags, unsigned long *prot, resource_size_t *phys);
2319 : int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
2320 : void *buf, int len, int write);
2321 :
2322 : extern void truncate_pagecache(struct inode *inode, loff_t new);
2323 : extern void truncate_setsize(struct inode *inode, loff_t newsize);
2324 : void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
2325 : void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
2326 : int generic_error_remove_page(struct address_space *mapping, struct page *page);
2327 :
2328 : struct vm_area_struct *lock_mm_and_find_vma(struct mm_struct *mm,
2329 : unsigned long address, struct pt_regs *regs);
2330 :
2331 : #ifdef CONFIG_MMU
2332 : extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
2333 : unsigned long address, unsigned int flags,
2334 : struct pt_regs *regs);
2335 : extern int fixup_user_fault(struct mm_struct *mm,
2336 : unsigned long address, unsigned int fault_flags,
2337 : bool *unlocked);
2338 : void unmap_mapping_pages(struct address_space *mapping,
2339 : pgoff_t start, pgoff_t nr, bool even_cows);
2340 : void unmap_mapping_range(struct address_space *mapping,
2341 : loff_t const holebegin, loff_t const holelen, int even_cows);
2342 : #else
2343 : static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
2344 : unsigned long address, unsigned int flags,
2345 : struct pt_regs *regs)
2346 : {
2347 : /* should never happen if there's no MMU */
2348 : BUG();
2349 : return VM_FAULT_SIGBUS;
2350 : }
2351 : static inline int fixup_user_fault(struct mm_struct *mm, unsigned long address,
2352 : unsigned int fault_flags, bool *unlocked)
2353 : {
2354 : /* should never happen if there's no MMU */
2355 : BUG();
2356 : return -EFAULT;
2357 : }
2358 : static inline void unmap_mapping_pages(struct address_space *mapping,
2359 : pgoff_t start, pgoff_t nr, bool even_cows) { }
2360 : static inline void unmap_mapping_range(struct address_space *mapping,
2361 : loff_t const holebegin, loff_t const holelen, int even_cows) { }
2362 : #endif
2363 :
2364 : static inline void unmap_shared_mapping_range(struct address_space *mapping,
2365 : loff_t const holebegin, loff_t const holelen)
2366 : {
2367 : unmap_mapping_range(mapping, holebegin, holelen, 0);
2368 : }
2369 :
2370 : static inline struct vm_area_struct *vma_lookup(struct mm_struct *mm,
2371 : unsigned long addr);
2372 :
2373 : extern int access_process_vm(struct task_struct *tsk, unsigned long addr,
2374 : void *buf, int len, unsigned int gup_flags);
2375 : extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
2376 : void *buf, int len, unsigned int gup_flags);
2377 : extern int __access_remote_vm(struct mm_struct *mm, unsigned long addr,
2378 : void *buf, int len, unsigned int gup_flags);
2379 :
2380 : long get_user_pages_remote(struct mm_struct *mm,
2381 : unsigned long start, unsigned long nr_pages,
2382 : unsigned int gup_flags, struct page **pages,
2383 : int *locked);
2384 : long pin_user_pages_remote(struct mm_struct *mm,
2385 : unsigned long start, unsigned long nr_pages,
2386 : unsigned int gup_flags, struct page **pages,
2387 : int *locked);
2388 :
2389 0 : static inline struct page *get_user_page_vma_remote(struct mm_struct *mm,
2390 : unsigned long addr,
2391 : int gup_flags,
2392 : struct vm_area_struct **vmap)
2393 : {
2394 : struct page *page;
2395 : struct vm_area_struct *vma;
2396 0 : int got = get_user_pages_remote(mm, addr, 1, gup_flags, &page, NULL);
2397 :
2398 0 : if (got < 0)
2399 0 : return ERR_PTR(got);
2400 0 : if (got == 0)
2401 : return NULL;
2402 :
2403 0 : vma = vma_lookup(mm, addr);
2404 0 : if (WARN_ON_ONCE(!vma)) {
2405 0 : put_page(page);
2406 0 : return ERR_PTR(-EINVAL);
2407 : }
2408 :
2409 0 : *vmap = vma;
2410 0 : return page;
2411 : }
2412 :
2413 : long get_user_pages(unsigned long start, unsigned long nr_pages,
2414 : unsigned int gup_flags, struct page **pages);
2415 : long pin_user_pages(unsigned long start, unsigned long nr_pages,
2416 : unsigned int gup_flags, struct page **pages);
2417 : long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
2418 : struct page **pages, unsigned int gup_flags);
2419 : long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
2420 : struct page **pages, unsigned int gup_flags);
2421 :
2422 : int get_user_pages_fast(unsigned long start, int nr_pages,
2423 : unsigned int gup_flags, struct page **pages);
2424 : int pin_user_pages_fast(unsigned long start, int nr_pages,
2425 : unsigned int gup_flags, struct page **pages);
2426 : void folio_add_pin(struct folio *folio);
2427 :
2428 : int account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc);
2429 : int __account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc,
2430 : struct task_struct *task, bool bypass_rlim);
2431 :
2432 : struct kvec;
2433 : struct page *get_dump_page(unsigned long addr);
2434 :
2435 : bool folio_mark_dirty(struct folio *folio);
2436 : bool set_page_dirty(struct page *page);
2437 : int set_page_dirty_lock(struct page *page);
2438 :
2439 : int get_cmdline(struct task_struct *task, char *buffer, int buflen);
2440 :
2441 : extern unsigned long move_page_tables(struct vm_area_struct *vma,
2442 : unsigned long old_addr, struct vm_area_struct *new_vma,
2443 : unsigned long new_addr, unsigned long len,
2444 : bool need_rmap_locks);
2445 :
2446 : /*
2447 : * Flags used by change_protection(). For now we make it a bitmap so
2448 : * that we can pass in multiple flags just like parameters. However
2449 : * for now all the callers are only use one of the flags at the same
2450 : * time.
2451 : */
2452 : /*
2453 : * Whether we should manually check if we can map individual PTEs writable,
2454 : * because something (e.g., COW, uffd-wp) blocks that from happening for all
2455 : * PTEs automatically in a writable mapping.
2456 : */
2457 : #define MM_CP_TRY_CHANGE_WRITABLE (1UL << 0)
2458 : /* Whether this protection change is for NUMA hints */
2459 : #define MM_CP_PROT_NUMA (1UL << 1)
2460 : /* Whether this change is for write protecting */
2461 : #define MM_CP_UFFD_WP (1UL << 2) /* do wp */
2462 : #define MM_CP_UFFD_WP_RESOLVE (1UL << 3) /* Resolve wp */
2463 : #define MM_CP_UFFD_WP_ALL (MM_CP_UFFD_WP | \
2464 : MM_CP_UFFD_WP_RESOLVE)
2465 :
2466 : bool vma_needs_dirty_tracking(struct vm_area_struct *vma);
2467 : int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot);
2468 0 : static inline bool vma_wants_manual_pte_write_upgrade(struct vm_area_struct *vma)
2469 : {
2470 : /*
2471 : * We want to check manually if we can change individual PTEs writable
2472 : * if we can't do that automatically for all PTEs in a mapping. For
2473 : * private mappings, that's always the case when we have write
2474 : * permissions as we properly have to handle COW.
2475 : */
2476 0 : if (vma->vm_flags & VM_SHARED)
2477 0 : return vma_wants_writenotify(vma, vma->vm_page_prot);
2478 0 : return !!(vma->vm_flags & VM_WRITE);
2479 :
2480 : }
2481 : bool can_change_pte_writable(struct vm_area_struct *vma, unsigned long addr,
2482 : pte_t pte);
2483 : extern long change_protection(struct mmu_gather *tlb,
2484 : struct vm_area_struct *vma, unsigned long start,
2485 : unsigned long end, unsigned long cp_flags);
2486 : extern int mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb,
2487 : struct vm_area_struct *vma, struct vm_area_struct **pprev,
2488 : unsigned long start, unsigned long end, unsigned long newflags);
2489 :
2490 : /*
2491 : * doesn't attempt to fault and will return short.
2492 : */
2493 : int get_user_pages_fast_only(unsigned long start, int nr_pages,
2494 : unsigned int gup_flags, struct page **pages);
2495 :
2496 : static inline bool get_user_page_fast_only(unsigned long addr,
2497 : unsigned int gup_flags, struct page **pagep)
2498 : {
2499 : return get_user_pages_fast_only(addr, 1, gup_flags, pagep) == 1;
2500 : }
2501 : /*
2502 : * per-process(per-mm_struct) statistics.
2503 : */
2504 : static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
2505 : {
2506 0 : return percpu_counter_read_positive(&mm->rss_stat[member]);
2507 : }
2508 :
2509 : void mm_trace_rss_stat(struct mm_struct *mm, int member);
2510 :
2511 0 : static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
2512 : {
2513 0 : percpu_counter_add(&mm->rss_stat[member], value);
2514 :
2515 0 : mm_trace_rss_stat(mm, member);
2516 0 : }
2517 :
2518 : static inline void inc_mm_counter(struct mm_struct *mm, int member)
2519 : {
2520 0 : percpu_counter_inc(&mm->rss_stat[member]);
2521 :
2522 0 : mm_trace_rss_stat(mm, member);
2523 : }
2524 :
2525 : static inline void dec_mm_counter(struct mm_struct *mm, int member)
2526 : {
2527 0 : percpu_counter_dec(&mm->rss_stat[member]);
2528 :
2529 0 : mm_trace_rss_stat(mm, member);
2530 : }
2531 :
2532 : /* Optimized variant when page is already known not to be PageAnon */
2533 : static inline int mm_counter_file(struct page *page)
2534 : {
2535 0 : if (PageSwapBacked(page))
2536 : return MM_SHMEMPAGES;
2537 : return MM_FILEPAGES;
2538 : }
2539 :
2540 0 : static inline int mm_counter(struct page *page)
2541 : {
2542 0 : if (PageAnon(page))
2543 : return MM_ANONPAGES;
2544 : return mm_counter_file(page);
2545 : }
2546 :
2547 : static inline unsigned long get_mm_rss(struct mm_struct *mm)
2548 : {
2549 0 : return get_mm_counter(mm, MM_FILEPAGES) +
2550 0 : get_mm_counter(mm, MM_ANONPAGES) +
2551 0 : get_mm_counter(mm, MM_SHMEMPAGES);
2552 : }
2553 :
2554 : static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
2555 : {
2556 0 : return max(mm->hiwater_rss, get_mm_rss(mm));
2557 : }
2558 :
2559 : static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
2560 : {
2561 : return max(mm->hiwater_vm, mm->total_vm);
2562 : }
2563 :
2564 : static inline void update_hiwater_rss(struct mm_struct *mm)
2565 : {
2566 0 : unsigned long _rss = get_mm_rss(mm);
2567 :
2568 0 : if ((mm)->hiwater_rss < _rss)
2569 0 : (mm)->hiwater_rss = _rss;
2570 : }
2571 :
2572 : static inline void update_hiwater_vm(struct mm_struct *mm)
2573 : {
2574 0 : if (mm->hiwater_vm < mm->total_vm)
2575 0 : mm->hiwater_vm = mm->total_vm;
2576 : }
2577 :
2578 : static inline void reset_mm_hiwater_rss(struct mm_struct *mm)
2579 : {
2580 0 : mm->hiwater_rss = get_mm_rss(mm);
2581 : }
2582 :
2583 : static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
2584 : struct mm_struct *mm)
2585 : {
2586 0 : unsigned long hiwater_rss = get_mm_hiwater_rss(mm);
2587 :
2588 0 : if (*maxrss < hiwater_rss)
2589 0 : *maxrss = hiwater_rss;
2590 : }
2591 :
2592 : #if defined(SPLIT_RSS_COUNTING)
2593 : void sync_mm_rss(struct mm_struct *mm);
2594 : #else
2595 : static inline void sync_mm_rss(struct mm_struct *mm)
2596 : {
2597 : }
2598 : #endif
2599 :
2600 : #ifndef CONFIG_ARCH_HAS_PTE_SPECIAL
2601 : static inline int pte_special(pte_t pte)
2602 : {
2603 : return 0;
2604 : }
2605 :
2606 : static inline pte_t pte_mkspecial(pte_t pte)
2607 : {
2608 : return pte;
2609 : }
2610 : #endif
2611 :
2612 : #ifndef CONFIG_ARCH_HAS_PTE_DEVMAP
2613 : static inline int pte_devmap(pte_t pte)
2614 : {
2615 : return 0;
2616 : }
2617 : #endif
2618 :
2619 : extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
2620 : spinlock_t **ptl);
2621 : static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
2622 : spinlock_t **ptl)
2623 : {
2624 : pte_t *ptep;
2625 0 : __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl));
2626 : return ptep;
2627 : }
2628 :
2629 : #ifdef __PAGETABLE_P4D_FOLDED
2630 : static inline int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
2631 : unsigned long address)
2632 : {
2633 : return 0;
2634 : }
2635 : #else
2636 : int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
2637 : #endif
2638 :
2639 : #if defined(__PAGETABLE_PUD_FOLDED) || !defined(CONFIG_MMU)
2640 : static inline int __pud_alloc(struct mm_struct *mm, p4d_t *p4d,
2641 : unsigned long address)
2642 : {
2643 : return 0;
2644 : }
2645 : static inline void mm_inc_nr_puds(struct mm_struct *mm) {}
2646 : static inline void mm_dec_nr_puds(struct mm_struct *mm) {}
2647 :
2648 : #else
2649 : int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address);
2650 :
2651 : static inline void mm_inc_nr_puds(struct mm_struct *mm)
2652 : {
2653 : if (mm_pud_folded(mm))
2654 : return;
2655 : atomic_long_add(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
2656 : }
2657 :
2658 : static inline void mm_dec_nr_puds(struct mm_struct *mm)
2659 : {
2660 : if (mm_pud_folded(mm))
2661 : return;
2662 : atomic_long_sub(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
2663 : }
2664 : #endif
2665 :
2666 : #if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU)
2667 : static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
2668 : unsigned long address)
2669 : {
2670 : return 0;
2671 : }
2672 :
2673 : static inline void mm_inc_nr_pmds(struct mm_struct *mm) {}
2674 : static inline void mm_dec_nr_pmds(struct mm_struct *mm) {}
2675 :
2676 : #else
2677 : int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
2678 :
2679 : static inline void mm_inc_nr_pmds(struct mm_struct *mm)
2680 : {
2681 : if (mm_pmd_folded(mm))
2682 : return;
2683 2 : atomic_long_add(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2684 : }
2685 :
2686 : static inline void mm_dec_nr_pmds(struct mm_struct *mm)
2687 : {
2688 : if (mm_pmd_folded(mm))
2689 : return;
2690 0 : atomic_long_sub(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2691 : }
2692 : #endif
2693 :
2694 : #ifdef CONFIG_MMU
2695 : static inline void mm_pgtables_bytes_init(struct mm_struct *mm)
2696 : {
2697 0 : atomic_long_set(&mm->pgtables_bytes, 0);
2698 : }
2699 :
2700 : static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2701 : {
2702 0 : return atomic_long_read(&mm->pgtables_bytes);
2703 : }
2704 :
2705 : static inline void mm_inc_nr_ptes(struct mm_struct *mm)
2706 : {
2707 0 : atomic_long_add(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2708 : }
2709 :
2710 : static inline void mm_dec_nr_ptes(struct mm_struct *mm)
2711 : {
2712 0 : atomic_long_sub(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2713 : }
2714 : #else
2715 :
2716 : static inline void mm_pgtables_bytes_init(struct mm_struct *mm) {}
2717 : static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2718 : {
2719 : return 0;
2720 : }
2721 :
2722 : static inline void mm_inc_nr_ptes(struct mm_struct *mm) {}
2723 : static inline void mm_dec_nr_ptes(struct mm_struct *mm) {}
2724 : #endif
2725 :
2726 : int __pte_alloc(struct mm_struct *mm, pmd_t *pmd);
2727 : int __pte_alloc_kernel(pmd_t *pmd);
2728 :
2729 : #if defined(CONFIG_MMU)
2730 :
2731 : static inline p4d_t *p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
2732 : unsigned long address)
2733 : {
2734 0 : return (unlikely(pgd_none(*pgd)) && __p4d_alloc(mm, pgd, address)) ?
2735 0 : NULL : p4d_offset(pgd, address);
2736 : }
2737 :
2738 : static inline pud_t *pud_alloc(struct mm_struct *mm, p4d_t *p4d,
2739 : unsigned long address)
2740 : {
2741 0 : return (unlikely(p4d_none(*p4d)) && __pud_alloc(mm, p4d, address)) ?
2742 0 : NULL : pud_offset(p4d, address);
2743 : }
2744 :
2745 0 : static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
2746 : {
2747 0 : return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
2748 0 : NULL: pmd_offset(pud, address);
2749 : }
2750 : #endif /* CONFIG_MMU */
2751 :
2752 : #if USE_SPLIT_PTE_PTLOCKS
2753 : #if ALLOC_SPLIT_PTLOCKS
2754 : void __init ptlock_cache_init(void);
2755 : extern bool ptlock_alloc(struct page *page);
2756 : extern void ptlock_free(struct page *page);
2757 :
2758 : static inline spinlock_t *ptlock_ptr(struct page *page)
2759 : {
2760 : return page->ptl;
2761 : }
2762 : #else /* ALLOC_SPLIT_PTLOCKS */
2763 : static inline void ptlock_cache_init(void)
2764 : {
2765 : }
2766 :
2767 : static inline bool ptlock_alloc(struct page *page)
2768 : {
2769 : return true;
2770 : }
2771 :
2772 : static inline void ptlock_free(struct page *page)
2773 : {
2774 : }
2775 :
2776 : static inline spinlock_t *ptlock_ptr(struct page *page)
2777 : {
2778 : return &page->ptl;
2779 : }
2780 : #endif /* ALLOC_SPLIT_PTLOCKS */
2781 :
2782 : static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2783 : {
2784 : return ptlock_ptr(pmd_page(*pmd));
2785 : }
2786 :
2787 : static inline bool ptlock_init(struct page *page)
2788 : {
2789 : /*
2790 : * prep_new_page() initialize page->private (and therefore page->ptl)
2791 : * with 0. Make sure nobody took it in use in between.
2792 : *
2793 : * It can happen if arch try to use slab for page table allocation:
2794 : * slab code uses page->slab_cache, which share storage with page->ptl.
2795 : */
2796 : VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page);
2797 : if (!ptlock_alloc(page))
2798 : return false;
2799 : spin_lock_init(ptlock_ptr(page));
2800 : return true;
2801 : }
2802 :
2803 : #else /* !USE_SPLIT_PTE_PTLOCKS */
2804 : /*
2805 : * We use mm->page_table_lock to guard all pagetable pages of the mm.
2806 : */
2807 : static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2808 : {
2809 0 : return &mm->page_table_lock;
2810 : }
2811 : static inline void ptlock_cache_init(void) {}
2812 : static inline bool ptlock_init(struct page *page) { return true; }
2813 : static inline void ptlock_free(struct page *page) {}
2814 : #endif /* USE_SPLIT_PTE_PTLOCKS */
2815 :
2816 : static inline bool pgtable_pte_page_ctor(struct page *page)
2817 : {
2818 0 : if (!ptlock_init(page))
2819 : return false;
2820 0 : __SetPageTable(page);
2821 0 : inc_lruvec_page_state(page, NR_PAGETABLE);
2822 : return true;
2823 : }
2824 :
2825 : static inline void pgtable_pte_page_dtor(struct page *page)
2826 : {
2827 0 : ptlock_free(page);
2828 0 : __ClearPageTable(page);
2829 0 : dec_lruvec_page_state(page, NR_PAGETABLE);
2830 : }
2831 :
2832 : pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp);
2833 : static inline pte_t *pte_offset_map(pmd_t *pmd, unsigned long addr)
2834 : {
2835 0 : return __pte_offset_map(pmd, addr, NULL);
2836 : }
2837 :
2838 : pte_t *__pte_offset_map_lock(struct mm_struct *mm, pmd_t *pmd,
2839 : unsigned long addr, spinlock_t **ptlp);
2840 : static inline pte_t *pte_offset_map_lock(struct mm_struct *mm, pmd_t *pmd,
2841 : unsigned long addr, spinlock_t **ptlp)
2842 : {
2843 : pte_t *pte;
2844 :
2845 0 : __cond_lock(*ptlp, pte = __pte_offset_map_lock(mm, pmd, addr, ptlp));
2846 : return pte;
2847 : }
2848 :
2849 : pte_t *pte_offset_map_nolock(struct mm_struct *mm, pmd_t *pmd,
2850 : unsigned long addr, spinlock_t **ptlp);
2851 :
2852 : #define pte_unmap_unlock(pte, ptl) do { \
2853 : spin_unlock(ptl); \
2854 : pte_unmap(pte); \
2855 : } while (0)
2856 :
2857 : #define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd))
2858 :
2859 : #define pte_alloc_map(mm, pmd, address) \
2860 : (pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address))
2861 :
2862 : #define pte_alloc_map_lock(mm, pmd, address, ptlp) \
2863 : (pte_alloc(mm, pmd) ? \
2864 : NULL : pte_offset_map_lock(mm, pmd, address, ptlp))
2865 :
2866 : #define pte_alloc_kernel(pmd, address) \
2867 : ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \
2868 : NULL: pte_offset_kernel(pmd, address))
2869 :
2870 : #if USE_SPLIT_PMD_PTLOCKS
2871 :
2872 : static inline struct page *pmd_pgtable_page(pmd_t *pmd)
2873 : {
2874 : unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
2875 : return virt_to_page((void *)((unsigned long) pmd & mask));
2876 : }
2877 :
2878 : static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
2879 : {
2880 : return ptlock_ptr(pmd_pgtable_page(pmd));
2881 : }
2882 :
2883 : static inline bool pmd_ptlock_init(struct page *page)
2884 : {
2885 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2886 : page->pmd_huge_pte = NULL;
2887 : #endif
2888 : return ptlock_init(page);
2889 : }
2890 :
2891 : static inline void pmd_ptlock_free(struct page *page)
2892 : {
2893 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2894 : VM_BUG_ON_PAGE(page->pmd_huge_pte, page);
2895 : #endif
2896 : ptlock_free(page);
2897 : }
2898 :
2899 : #define pmd_huge_pte(mm, pmd) (pmd_pgtable_page(pmd)->pmd_huge_pte)
2900 :
2901 : #else
2902 :
2903 : static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
2904 : {
2905 : return &mm->page_table_lock;
2906 : }
2907 :
2908 : static inline bool pmd_ptlock_init(struct page *page) { return true; }
2909 : static inline void pmd_ptlock_free(struct page *page) {}
2910 :
2911 : #define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte)
2912 :
2913 : #endif
2914 :
2915 : static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd)
2916 : {
2917 0 : spinlock_t *ptl = pmd_lockptr(mm, pmd);
2918 0 : spin_lock(ptl);
2919 : return ptl;
2920 : }
2921 :
2922 : static inline bool pgtable_pmd_page_ctor(struct page *page)
2923 : {
2924 1 : if (!pmd_ptlock_init(page))
2925 : return false;
2926 1 : __SetPageTable(page);
2927 2 : inc_lruvec_page_state(page, NR_PAGETABLE);
2928 : return true;
2929 : }
2930 :
2931 : static inline void pgtable_pmd_page_dtor(struct page *page)
2932 : {
2933 0 : pmd_ptlock_free(page);
2934 0 : __ClearPageTable(page);
2935 0 : dec_lruvec_page_state(page, NR_PAGETABLE);
2936 : }
2937 :
2938 : /*
2939 : * No scalability reason to split PUD locks yet, but follow the same pattern
2940 : * as the PMD locks to make it easier if we decide to. The VM should not be
2941 : * considered ready to switch to split PUD locks yet; there may be places
2942 : * which need to be converted from page_table_lock.
2943 : */
2944 : static inline spinlock_t *pud_lockptr(struct mm_struct *mm, pud_t *pud)
2945 : {
2946 : return &mm->page_table_lock;
2947 : }
2948 :
2949 : static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud)
2950 : {
2951 1 : spinlock_t *ptl = pud_lockptr(mm, pud);
2952 :
2953 1 : spin_lock(ptl);
2954 : return ptl;
2955 : }
2956 :
2957 : extern void __init pagecache_init(void);
2958 : extern void free_initmem(void);
2959 :
2960 : /*
2961 : * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
2962 : * into the buddy system. The freed pages will be poisoned with pattern
2963 : * "poison" if it's within range [0, UCHAR_MAX].
2964 : * Return pages freed into the buddy system.
2965 : */
2966 : extern unsigned long free_reserved_area(void *start, void *end,
2967 : int poison, const char *s);
2968 :
2969 : extern void adjust_managed_page_count(struct page *page, long count);
2970 :
2971 : extern void reserve_bootmem_region(phys_addr_t start,
2972 : phys_addr_t end, int nid);
2973 :
2974 : /* Free the reserved page into the buddy system, so it gets managed. */
2975 : static inline void free_reserved_page(struct page *page)
2976 : {
2977 0 : ClearPageReserved(page);
2978 0 : init_page_count(page);
2979 0 : __free_page(page);
2980 0 : adjust_managed_page_count(page, 1);
2981 : }
2982 : #define free_highmem_page(page) free_reserved_page(page)
2983 :
2984 : static inline void mark_page_reserved(struct page *page)
2985 : {
2986 : SetPageReserved(page);
2987 : adjust_managed_page_count(page, -1);
2988 : }
2989 :
2990 : /*
2991 : * Default method to free all the __init memory into the buddy system.
2992 : * The freed pages will be poisoned with pattern "poison" if it's within
2993 : * range [0, UCHAR_MAX].
2994 : * Return pages freed into the buddy system.
2995 : */
2996 : static inline unsigned long free_initmem_default(int poison)
2997 : {
2998 : extern char __init_begin[], __init_end[];
2999 :
3000 0 : return free_reserved_area(&__init_begin, &__init_end,
3001 : poison, "unused kernel image (initmem)");
3002 : }
3003 :
3004 : static inline unsigned long get_num_physpages(void)
3005 : {
3006 : int nid;
3007 1 : unsigned long phys_pages = 0;
3008 :
3009 2 : for_each_online_node(nid)
3010 1 : phys_pages += node_present_pages(nid);
3011 :
3012 : return phys_pages;
3013 : }
3014 :
3015 : /*
3016 : * Using memblock node mappings, an architecture may initialise its
3017 : * zones, allocate the backing mem_map and account for memory holes in an
3018 : * architecture independent manner.
3019 : *
3020 : * An architecture is expected to register range of page frames backed by
3021 : * physical memory with memblock_add[_node]() before calling
3022 : * free_area_init() passing in the PFN each zone ends at. At a basic
3023 : * usage, an architecture is expected to do something like
3024 : *
3025 : * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
3026 : * max_highmem_pfn};
3027 : * for_each_valid_physical_page_range()
3028 : * memblock_add_node(base, size, nid, MEMBLOCK_NONE)
3029 : * free_area_init(max_zone_pfns);
3030 : */
3031 : void free_area_init(unsigned long *max_zone_pfn);
3032 : unsigned long node_map_pfn_alignment(void);
3033 : unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn,
3034 : unsigned long end_pfn);
3035 : extern unsigned long absent_pages_in_range(unsigned long start_pfn,
3036 : unsigned long end_pfn);
3037 : extern void get_pfn_range_for_nid(unsigned int nid,
3038 : unsigned long *start_pfn, unsigned long *end_pfn);
3039 :
3040 : #ifndef CONFIG_NUMA
3041 : static inline int early_pfn_to_nid(unsigned long pfn)
3042 : {
3043 : return 0;
3044 : }
3045 : #else
3046 : /* please see mm/page_alloc.c */
3047 : extern int __meminit early_pfn_to_nid(unsigned long pfn);
3048 : #endif
3049 :
3050 : extern void set_dma_reserve(unsigned long new_dma_reserve);
3051 : extern void mem_init(void);
3052 : extern void __init mmap_init(void);
3053 :
3054 : extern void __show_mem(unsigned int flags, nodemask_t *nodemask, int max_zone_idx);
3055 : static inline void show_mem(unsigned int flags, nodemask_t *nodemask)
3056 : {
3057 0 : __show_mem(flags, nodemask, MAX_NR_ZONES - 1);
3058 : }
3059 : extern long si_mem_available(void);
3060 : extern void si_meminfo(struct sysinfo * val);
3061 : extern void si_meminfo_node(struct sysinfo *val, int nid);
3062 : #ifdef __HAVE_ARCH_RESERVED_KERNEL_PAGES
3063 : extern unsigned long arch_reserved_kernel_pages(void);
3064 : #endif
3065 :
3066 : extern __printf(3, 4)
3067 : void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...);
3068 :
3069 : extern void setup_per_cpu_pageset(void);
3070 :
3071 : /* nommu.c */
3072 : extern atomic_long_t mmap_pages_allocated;
3073 : extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
3074 :
3075 : /* interval_tree.c */
3076 : void vma_interval_tree_insert(struct vm_area_struct *node,
3077 : struct rb_root_cached *root);
3078 : void vma_interval_tree_insert_after(struct vm_area_struct *node,
3079 : struct vm_area_struct *prev,
3080 : struct rb_root_cached *root);
3081 : void vma_interval_tree_remove(struct vm_area_struct *node,
3082 : struct rb_root_cached *root);
3083 : struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root_cached *root,
3084 : unsigned long start, unsigned long last);
3085 : struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
3086 : unsigned long start, unsigned long last);
3087 :
3088 : #define vma_interval_tree_foreach(vma, root, start, last) \
3089 : for (vma = vma_interval_tree_iter_first(root, start, last); \
3090 : vma; vma = vma_interval_tree_iter_next(vma, start, last))
3091 :
3092 : void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
3093 : struct rb_root_cached *root);
3094 : void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
3095 : struct rb_root_cached *root);
3096 : struct anon_vma_chain *
3097 : anon_vma_interval_tree_iter_first(struct rb_root_cached *root,
3098 : unsigned long start, unsigned long last);
3099 : struct anon_vma_chain *anon_vma_interval_tree_iter_next(
3100 : struct anon_vma_chain *node, unsigned long start, unsigned long last);
3101 : #ifdef CONFIG_DEBUG_VM_RB
3102 : void anon_vma_interval_tree_verify(struct anon_vma_chain *node);
3103 : #endif
3104 :
3105 : #define anon_vma_interval_tree_foreach(avc, root, start, last) \
3106 : for (avc = anon_vma_interval_tree_iter_first(root, start, last); \
3107 : avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))
3108 :
3109 : /* mmap.c */
3110 : extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin);
3111 : extern int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma,
3112 : unsigned long start, unsigned long end, pgoff_t pgoff,
3113 : struct vm_area_struct *next);
3114 : extern int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma,
3115 : unsigned long start, unsigned long end, pgoff_t pgoff);
3116 : extern struct vm_area_struct *vma_merge(struct vma_iterator *vmi,
3117 : struct mm_struct *, struct vm_area_struct *prev, unsigned long addr,
3118 : unsigned long end, unsigned long vm_flags, struct anon_vma *,
3119 : struct file *, pgoff_t, struct mempolicy *, struct vm_userfaultfd_ctx,
3120 : struct anon_vma_name *);
3121 : extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
3122 : extern int __split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
3123 : unsigned long addr, int new_below);
3124 : extern int split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
3125 : unsigned long addr, int new_below);
3126 : extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
3127 : extern void unlink_file_vma(struct vm_area_struct *);
3128 : extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
3129 : unsigned long addr, unsigned long len, pgoff_t pgoff,
3130 : bool *need_rmap_locks);
3131 : extern void exit_mmap(struct mm_struct *);
3132 :
3133 : static inline int check_data_rlimit(unsigned long rlim,
3134 : unsigned long new,
3135 : unsigned long start,
3136 : unsigned long end_data,
3137 : unsigned long start_data)
3138 : {
3139 0 : if (rlim < RLIM_INFINITY) {
3140 0 : if (((new - start) + (end_data - start_data)) > rlim)
3141 : return -ENOSPC;
3142 : }
3143 :
3144 : return 0;
3145 : }
3146 :
3147 : extern int mm_take_all_locks(struct mm_struct *mm);
3148 : extern void mm_drop_all_locks(struct mm_struct *mm);
3149 :
3150 : extern int set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
3151 : extern int replace_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
3152 : extern struct file *get_mm_exe_file(struct mm_struct *mm);
3153 : extern struct file *get_task_exe_file(struct task_struct *task);
3154 :
3155 : extern bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long npages);
3156 : extern void vm_stat_account(struct mm_struct *, vm_flags_t, long npages);
3157 :
3158 : extern bool vma_is_special_mapping(const struct vm_area_struct *vma,
3159 : const struct vm_special_mapping *sm);
3160 : extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm,
3161 : unsigned long addr, unsigned long len,
3162 : unsigned long flags,
3163 : const struct vm_special_mapping *spec);
3164 : /* This is an obsolete alternative to _install_special_mapping. */
3165 : extern int install_special_mapping(struct mm_struct *mm,
3166 : unsigned long addr, unsigned long len,
3167 : unsigned long flags, struct page **pages);
3168 :
3169 : unsigned long randomize_stack_top(unsigned long stack_top);
3170 : unsigned long randomize_page(unsigned long start, unsigned long range);
3171 :
3172 : extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
3173 :
3174 : extern unsigned long mmap_region(struct file *file, unsigned long addr,
3175 : unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
3176 : struct list_head *uf);
3177 : extern unsigned long do_mmap(struct file *file, unsigned long addr,
3178 : unsigned long len, unsigned long prot, unsigned long flags,
3179 : unsigned long pgoff, unsigned long *populate, struct list_head *uf);
3180 : extern int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm,
3181 : unsigned long start, size_t len, struct list_head *uf,
3182 : bool unlock);
3183 : extern int do_munmap(struct mm_struct *, unsigned long, size_t,
3184 : struct list_head *uf);
3185 : extern int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior);
3186 :
3187 : #ifdef CONFIG_MMU
3188 : extern int do_vma_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma,
3189 : unsigned long start, unsigned long end,
3190 : struct list_head *uf, bool unlock);
3191 : extern int __mm_populate(unsigned long addr, unsigned long len,
3192 : int ignore_errors);
3193 : static inline void mm_populate(unsigned long addr, unsigned long len)
3194 : {
3195 : /* Ignore errors */
3196 0 : (void) __mm_populate(addr, len, 1);
3197 : }
3198 : #else
3199 : static inline void mm_populate(unsigned long addr, unsigned long len) {}
3200 : #endif
3201 :
3202 : /* These take the mm semaphore themselves */
3203 : extern int __must_check vm_brk(unsigned long, unsigned long);
3204 : extern int __must_check vm_brk_flags(unsigned long, unsigned long, unsigned long);
3205 : extern int vm_munmap(unsigned long, size_t);
3206 : extern unsigned long __must_check vm_mmap(struct file *, unsigned long,
3207 : unsigned long, unsigned long,
3208 : unsigned long, unsigned long);
3209 :
3210 : struct vm_unmapped_area_info {
3211 : #define VM_UNMAPPED_AREA_TOPDOWN 1
3212 : unsigned long flags;
3213 : unsigned long length;
3214 : unsigned long low_limit;
3215 : unsigned long high_limit;
3216 : unsigned long align_mask;
3217 : unsigned long align_offset;
3218 : };
3219 :
3220 : extern unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info);
3221 :
3222 : /* truncate.c */
3223 : extern void truncate_inode_pages(struct address_space *, loff_t);
3224 : extern void truncate_inode_pages_range(struct address_space *,
3225 : loff_t lstart, loff_t lend);
3226 : extern void truncate_inode_pages_final(struct address_space *);
3227 :
3228 : /* generic vm_area_ops exported for stackable file systems */
3229 : extern vm_fault_t filemap_fault(struct vm_fault *vmf);
3230 : extern vm_fault_t filemap_map_pages(struct vm_fault *vmf,
3231 : pgoff_t start_pgoff, pgoff_t end_pgoff);
3232 : extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf);
3233 :
3234 : extern unsigned long stack_guard_gap;
3235 : /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
3236 : int expand_stack_locked(struct vm_area_struct *vma, unsigned long address);
3237 : struct vm_area_struct *expand_stack(struct mm_struct * mm, unsigned long addr);
3238 :
3239 : /* CONFIG_STACK_GROWSUP still needs to grow downwards at some places */
3240 : int expand_downwards(struct vm_area_struct *vma, unsigned long address);
3241 :
3242 : /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */
3243 : extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
3244 : extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
3245 : struct vm_area_struct **pprev);
3246 :
3247 : /*
3248 : * Look up the first VMA which intersects the interval [start_addr, end_addr)
3249 : * NULL if none. Assume start_addr < end_addr.
3250 : */
3251 : struct vm_area_struct *find_vma_intersection(struct mm_struct *mm,
3252 : unsigned long start_addr, unsigned long end_addr);
3253 :
3254 : /**
3255 : * vma_lookup() - Find a VMA at a specific address
3256 : * @mm: The process address space.
3257 : * @addr: The user address.
3258 : *
3259 : * Return: The vm_area_struct at the given address, %NULL otherwise.
3260 : */
3261 : static inline
3262 : struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr)
3263 : {
3264 0 : return mtree_load(&mm->mm_mt, addr);
3265 : }
3266 :
3267 : static inline unsigned long vm_start_gap(struct vm_area_struct *vma)
3268 : {
3269 0 : unsigned long vm_start = vma->vm_start;
3270 :
3271 0 : if (vma->vm_flags & VM_GROWSDOWN) {
3272 0 : vm_start -= stack_guard_gap;
3273 0 : if (vm_start > vma->vm_start)
3274 0 : vm_start = 0;
3275 : }
3276 : return vm_start;
3277 : }
3278 :
3279 : static inline unsigned long vm_end_gap(struct vm_area_struct *vma)
3280 : {
3281 0 : unsigned long vm_end = vma->vm_end;
3282 :
3283 : if (vma->vm_flags & VM_GROWSUP) {
3284 : vm_end += stack_guard_gap;
3285 : if (vm_end < vma->vm_end)
3286 : vm_end = -PAGE_SIZE;
3287 : }
3288 : return vm_end;
3289 : }
3290 :
3291 : static inline unsigned long vma_pages(struct vm_area_struct *vma)
3292 : {
3293 0 : return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
3294 : }
3295 :
3296 : /* Look up the first VMA which exactly match the interval vm_start ... vm_end */
3297 : static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
3298 : unsigned long vm_start, unsigned long vm_end)
3299 : {
3300 0 : struct vm_area_struct *vma = vma_lookup(mm, vm_start);
3301 :
3302 0 : if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
3303 0 : vma = NULL;
3304 :
3305 : return vma;
3306 : }
3307 :
3308 : static inline bool range_in_vma(struct vm_area_struct *vma,
3309 : unsigned long start, unsigned long end)
3310 : {
3311 0 : return (vma && vma->vm_start <= start && end <= vma->vm_end);
3312 : }
3313 :
3314 : #ifdef CONFIG_MMU
3315 : pgprot_t vm_get_page_prot(unsigned long vm_flags);
3316 : void vma_set_page_prot(struct vm_area_struct *vma);
3317 : #else
3318 : static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
3319 : {
3320 : return __pgprot(0);
3321 : }
3322 : static inline void vma_set_page_prot(struct vm_area_struct *vma)
3323 : {
3324 : vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
3325 : }
3326 : #endif
3327 :
3328 : void vma_set_file(struct vm_area_struct *vma, struct file *file);
3329 :
3330 : #ifdef CONFIG_NUMA_BALANCING
3331 : unsigned long change_prot_numa(struct vm_area_struct *vma,
3332 : unsigned long start, unsigned long end);
3333 : #endif
3334 :
3335 : struct vm_area_struct *find_extend_vma_locked(struct mm_struct *,
3336 : unsigned long addr);
3337 : int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
3338 : unsigned long pfn, unsigned long size, pgprot_t);
3339 : int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr,
3340 : unsigned long pfn, unsigned long size, pgprot_t prot);
3341 : int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
3342 : int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr,
3343 : struct page **pages, unsigned long *num);
3344 : int vm_map_pages(struct vm_area_struct *vma, struct page **pages,
3345 : unsigned long num);
3346 : int vm_map_pages_zero(struct vm_area_struct *vma, struct page **pages,
3347 : unsigned long num);
3348 : vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
3349 : unsigned long pfn);
3350 : vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
3351 : unsigned long pfn, pgprot_t pgprot);
3352 : vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
3353 : pfn_t pfn);
3354 : vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
3355 : unsigned long addr, pfn_t pfn);
3356 : int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
3357 :
3358 : static inline vm_fault_t vmf_insert_page(struct vm_area_struct *vma,
3359 : unsigned long addr, struct page *page)
3360 : {
3361 : int err = vm_insert_page(vma, addr, page);
3362 :
3363 : if (err == -ENOMEM)
3364 : return VM_FAULT_OOM;
3365 : if (err < 0 && err != -EBUSY)
3366 : return VM_FAULT_SIGBUS;
3367 :
3368 : return VM_FAULT_NOPAGE;
3369 : }
3370 :
3371 : #ifndef io_remap_pfn_range
3372 : static inline int io_remap_pfn_range(struct vm_area_struct *vma,
3373 : unsigned long addr, unsigned long pfn,
3374 : unsigned long size, pgprot_t prot)
3375 : {
3376 0 : return remap_pfn_range(vma, addr, pfn, size, pgprot_decrypted(prot));
3377 : }
3378 : #endif
3379 :
3380 : static inline vm_fault_t vmf_error(int err)
3381 : {
3382 0 : if (err == -ENOMEM)
3383 : return VM_FAULT_OOM;
3384 0 : else if (err == -EHWPOISON)
3385 : return VM_FAULT_HWPOISON;
3386 : return VM_FAULT_SIGBUS;
3387 : }
3388 :
3389 : struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
3390 : unsigned int foll_flags);
3391 :
3392 : static inline int vm_fault_to_errno(vm_fault_t vm_fault, int foll_flags)
3393 : {
3394 0 : if (vm_fault & VM_FAULT_OOM)
3395 : return -ENOMEM;
3396 0 : if (vm_fault & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE))
3397 0 : return (foll_flags & FOLL_HWPOISON) ? -EHWPOISON : -EFAULT;
3398 0 : if (vm_fault & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV))
3399 : return -EFAULT;
3400 : return 0;
3401 : }
3402 :
3403 : /*
3404 : * Indicates whether GUP can follow a PROT_NONE mapped page, or whether
3405 : * a (NUMA hinting) fault is required.
3406 : */
3407 : static inline bool gup_can_follow_protnone(unsigned int flags)
3408 : {
3409 : /*
3410 : * FOLL_FORCE has to be able to make progress even if the VMA is
3411 : * inaccessible. Further, FOLL_FORCE access usually does not represent
3412 : * application behaviour and we should avoid triggering NUMA hinting
3413 : * faults.
3414 : */
3415 : return flags & FOLL_FORCE;
3416 : }
3417 :
3418 : typedef int (*pte_fn_t)(pte_t *pte, unsigned long addr, void *data);
3419 : extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
3420 : unsigned long size, pte_fn_t fn, void *data);
3421 : extern int apply_to_existing_page_range(struct mm_struct *mm,
3422 : unsigned long address, unsigned long size,
3423 : pte_fn_t fn, void *data);
3424 :
3425 : #ifdef CONFIG_PAGE_POISONING
3426 : extern void __kernel_poison_pages(struct page *page, int numpages);
3427 : extern void __kernel_unpoison_pages(struct page *page, int numpages);
3428 : extern bool _page_poisoning_enabled_early;
3429 : DECLARE_STATIC_KEY_FALSE(_page_poisoning_enabled);
3430 : static inline bool page_poisoning_enabled(void)
3431 : {
3432 : return _page_poisoning_enabled_early;
3433 : }
3434 : /*
3435 : * For use in fast paths after init_mem_debugging() has run, or when a
3436 : * false negative result is not harmful when called too early.
3437 : */
3438 : static inline bool page_poisoning_enabled_static(void)
3439 : {
3440 : return static_branch_unlikely(&_page_poisoning_enabled);
3441 : }
3442 : static inline void kernel_poison_pages(struct page *page, int numpages)
3443 : {
3444 : if (page_poisoning_enabled_static())
3445 : __kernel_poison_pages(page, numpages);
3446 : }
3447 : static inline void kernel_unpoison_pages(struct page *page, int numpages)
3448 : {
3449 : if (page_poisoning_enabled_static())
3450 : __kernel_unpoison_pages(page, numpages);
3451 : }
3452 : #else
3453 : static inline bool page_poisoning_enabled(void) { return false; }
3454 : static inline bool page_poisoning_enabled_static(void) { return false; }
3455 : static inline void __kernel_poison_pages(struct page *page, int nunmpages) { }
3456 : static inline void kernel_poison_pages(struct page *page, int numpages) { }
3457 : static inline void kernel_unpoison_pages(struct page *page, int numpages) { }
3458 : #endif
3459 :
3460 : DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
3461 : static inline bool want_init_on_alloc(gfp_t flags)
3462 : {
3463 522 : if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
3464 : &init_on_alloc))
3465 : return true;
3466 505 : return flags & __GFP_ZERO;
3467 : }
3468 :
3469 : DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free);
3470 0 : static inline bool want_init_on_free(void)
3471 : {
3472 782 : return static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
3473 : &init_on_free);
3474 : }
3475 :
3476 : extern bool _debug_pagealloc_enabled_early;
3477 : DECLARE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
3478 :
3479 : static inline bool debug_pagealloc_enabled(void)
3480 : {
3481 : return IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) &&
3482 : _debug_pagealloc_enabled_early;
3483 : }
3484 :
3485 : /*
3486 : * For use in fast paths after init_debug_pagealloc() has run, or when a
3487 : * false negative result is not harmful when called too early.
3488 : */
3489 : static inline bool debug_pagealloc_enabled_static(void)
3490 : {
3491 : if (!IS_ENABLED(CONFIG_DEBUG_PAGEALLOC))
3492 : return false;
3493 :
3494 : return static_branch_unlikely(&_debug_pagealloc_enabled);
3495 : }
3496 :
3497 : /*
3498 : * To support DEBUG_PAGEALLOC architecture must ensure that
3499 : * __kernel_map_pages() never fails
3500 : */
3501 : extern void __kernel_map_pages(struct page *page, int numpages, int enable);
3502 : #ifdef CONFIG_DEBUG_PAGEALLOC
3503 : static inline void debug_pagealloc_map_pages(struct page *page, int numpages)
3504 : {
3505 : if (debug_pagealloc_enabled_static())
3506 : __kernel_map_pages(page, numpages, 1);
3507 : }
3508 :
3509 : static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages)
3510 : {
3511 : if (debug_pagealloc_enabled_static())
3512 : __kernel_map_pages(page, numpages, 0);
3513 : }
3514 :
3515 : extern unsigned int _debug_guardpage_minorder;
3516 : DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
3517 :
3518 : static inline unsigned int debug_guardpage_minorder(void)
3519 : {
3520 : return _debug_guardpage_minorder;
3521 : }
3522 :
3523 : static inline bool debug_guardpage_enabled(void)
3524 : {
3525 : return static_branch_unlikely(&_debug_guardpage_enabled);
3526 : }
3527 :
3528 : static inline bool page_is_guard(struct page *page)
3529 : {
3530 : if (!debug_guardpage_enabled())
3531 : return false;
3532 :
3533 : return PageGuard(page);
3534 : }
3535 :
3536 : bool __set_page_guard(struct zone *zone, struct page *page, unsigned int order,
3537 : int migratetype);
3538 : static inline bool set_page_guard(struct zone *zone, struct page *page,
3539 : unsigned int order, int migratetype)
3540 : {
3541 : if (!debug_guardpage_enabled())
3542 : return false;
3543 : return __set_page_guard(zone, page, order, migratetype);
3544 : }
3545 :
3546 : void __clear_page_guard(struct zone *zone, struct page *page, unsigned int order,
3547 : int migratetype);
3548 : static inline void clear_page_guard(struct zone *zone, struct page *page,
3549 : unsigned int order, int migratetype)
3550 : {
3551 : if (!debug_guardpage_enabled())
3552 : return;
3553 : __clear_page_guard(zone, page, order, migratetype);
3554 : }
3555 :
3556 : #else /* CONFIG_DEBUG_PAGEALLOC */
3557 : static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {}
3558 : static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {}
3559 : static inline unsigned int debug_guardpage_minorder(void) { return 0; }
3560 : static inline bool debug_guardpage_enabled(void) { return false; }
3561 : static inline bool page_is_guard(struct page *page) { return false; }
3562 : static inline bool set_page_guard(struct zone *zone, struct page *page,
3563 : unsigned int order, int migratetype) { return false; }
3564 : static inline void clear_page_guard(struct zone *zone, struct page *page,
3565 : unsigned int order, int migratetype) {}
3566 : #endif /* CONFIG_DEBUG_PAGEALLOC */
3567 :
3568 : #ifdef __HAVE_ARCH_GATE_AREA
3569 : extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
3570 : extern int in_gate_area_no_mm(unsigned long addr);
3571 : extern int in_gate_area(struct mm_struct *mm, unsigned long addr);
3572 : #else
3573 : static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
3574 : {
3575 : return NULL;
3576 : }
3577 : static inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
3578 : static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
3579 : {
3580 : return 0;
3581 : }
3582 : #endif /* __HAVE_ARCH_GATE_AREA */
3583 :
3584 : extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm);
3585 :
3586 : #ifdef CONFIG_SYSCTL
3587 : extern int sysctl_drop_caches;
3588 : int drop_caches_sysctl_handler(struct ctl_table *, int, void *, size_t *,
3589 : loff_t *);
3590 : #endif
3591 :
3592 : void drop_slab(void);
3593 :
3594 : #ifndef CONFIG_MMU
3595 : #define randomize_va_space 0
3596 : #else
3597 : extern int randomize_va_space;
3598 : #endif
3599 :
3600 : const char * arch_vma_name(struct vm_area_struct *vma);
3601 : #ifdef CONFIG_MMU
3602 : void print_vma_addr(char *prefix, unsigned long rip);
3603 : #else
3604 : static inline void print_vma_addr(char *prefix, unsigned long rip)
3605 : {
3606 : }
3607 : #endif
3608 :
3609 : void *sparse_buffer_alloc(unsigned long size);
3610 : struct page * __populate_section_memmap(unsigned long pfn,
3611 : unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
3612 : struct dev_pagemap *pgmap);
3613 : void pmd_init(void *addr);
3614 : void pud_init(void *addr);
3615 : pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
3616 : p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node);
3617 : pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node);
3618 : pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
3619 : pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
3620 : struct vmem_altmap *altmap, struct page *reuse);
3621 : void *vmemmap_alloc_block(unsigned long size, int node);
3622 : struct vmem_altmap;
3623 : void *vmemmap_alloc_block_buf(unsigned long size, int node,
3624 : struct vmem_altmap *altmap);
3625 : void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
3626 : void vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
3627 : unsigned long addr, unsigned long next);
3628 : int vmemmap_check_pmd(pmd_t *pmd, int node,
3629 : unsigned long addr, unsigned long next);
3630 : int vmemmap_populate_basepages(unsigned long start, unsigned long end,
3631 : int node, struct vmem_altmap *altmap);
3632 : int vmemmap_populate_hugepages(unsigned long start, unsigned long end,
3633 : int node, struct vmem_altmap *altmap);
3634 : int vmemmap_populate(unsigned long start, unsigned long end, int node,
3635 : struct vmem_altmap *altmap);
3636 : void vmemmap_populate_print_last(void);
3637 : #ifdef CONFIG_MEMORY_HOTPLUG
3638 : void vmemmap_free(unsigned long start, unsigned long end,
3639 : struct vmem_altmap *altmap);
3640 : #endif
3641 :
3642 : #ifdef CONFIG_ARCH_WANT_OPTIMIZE_VMEMMAP
3643 : static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap,
3644 : struct dev_pagemap *pgmap)
3645 : {
3646 : return is_power_of_2(sizeof(struct page)) &&
3647 : pgmap && (pgmap_vmemmap_nr(pgmap) > 1) && !altmap;
3648 : }
3649 : #else
3650 : static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap,
3651 : struct dev_pagemap *pgmap)
3652 : {
3653 : return false;
3654 : }
3655 : #endif
3656 :
3657 : void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
3658 : unsigned long nr_pages);
3659 :
3660 : enum mf_flags {
3661 : MF_COUNT_INCREASED = 1 << 0,
3662 : MF_ACTION_REQUIRED = 1 << 1,
3663 : MF_MUST_KILL = 1 << 2,
3664 : MF_SOFT_OFFLINE = 1 << 3,
3665 : MF_UNPOISON = 1 << 4,
3666 : MF_SW_SIMULATED = 1 << 5,
3667 : MF_NO_RETRY = 1 << 6,
3668 : };
3669 : int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index,
3670 : unsigned long count, int mf_flags);
3671 : extern int memory_failure(unsigned long pfn, int flags);
3672 : extern void memory_failure_queue_kick(int cpu);
3673 : extern int unpoison_memory(unsigned long pfn);
3674 : extern void shake_page(struct page *p);
3675 : extern atomic_long_t num_poisoned_pages __read_mostly;
3676 : extern int soft_offline_page(unsigned long pfn, int flags);
3677 : #ifdef CONFIG_MEMORY_FAILURE
3678 : /*
3679 : * Sysfs entries for memory failure handling statistics.
3680 : */
3681 : extern const struct attribute_group memory_failure_attr_group;
3682 : extern void memory_failure_queue(unsigned long pfn, int flags);
3683 : extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
3684 : bool *migratable_cleared);
3685 : void num_poisoned_pages_inc(unsigned long pfn);
3686 : void num_poisoned_pages_sub(unsigned long pfn, long i);
3687 : struct task_struct *task_early_kill(struct task_struct *tsk, int force_early);
3688 : #else
3689 : static inline void memory_failure_queue(unsigned long pfn, int flags)
3690 : {
3691 : }
3692 :
3693 : static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
3694 : bool *migratable_cleared)
3695 : {
3696 : return 0;
3697 : }
3698 :
3699 : static inline void num_poisoned_pages_inc(unsigned long pfn)
3700 : {
3701 : }
3702 :
3703 : static inline void num_poisoned_pages_sub(unsigned long pfn, long i)
3704 : {
3705 : }
3706 : #endif
3707 :
3708 : #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_KSM)
3709 : void add_to_kill_ksm(struct task_struct *tsk, struct page *p,
3710 : struct vm_area_struct *vma, struct list_head *to_kill,
3711 : unsigned long ksm_addr);
3712 : #endif
3713 :
3714 : #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG)
3715 : extern void memblk_nr_poison_inc(unsigned long pfn);
3716 : extern void memblk_nr_poison_sub(unsigned long pfn, long i);
3717 : #else
3718 : static inline void memblk_nr_poison_inc(unsigned long pfn)
3719 : {
3720 : }
3721 :
3722 : static inline void memblk_nr_poison_sub(unsigned long pfn, long i)
3723 : {
3724 : }
3725 : #endif
3726 :
3727 : #ifndef arch_memory_failure
3728 : static inline int arch_memory_failure(unsigned long pfn, int flags)
3729 : {
3730 : return -ENXIO;
3731 : }
3732 : #endif
3733 :
3734 : #ifndef arch_is_platform_page
3735 : static inline bool arch_is_platform_page(u64 paddr)
3736 : {
3737 : return false;
3738 : }
3739 : #endif
3740 :
3741 : /*
3742 : * Error handlers for various types of pages.
3743 : */
3744 : enum mf_result {
3745 : MF_IGNORED, /* Error: cannot be handled */
3746 : MF_FAILED, /* Error: handling failed */
3747 : MF_DELAYED, /* Will be handled later */
3748 : MF_RECOVERED, /* Successfully recovered */
3749 : };
3750 :
3751 : enum mf_action_page_type {
3752 : MF_MSG_KERNEL,
3753 : MF_MSG_KERNEL_HIGH_ORDER,
3754 : MF_MSG_SLAB,
3755 : MF_MSG_DIFFERENT_COMPOUND,
3756 : MF_MSG_HUGE,
3757 : MF_MSG_FREE_HUGE,
3758 : MF_MSG_UNMAP_FAILED,
3759 : MF_MSG_DIRTY_SWAPCACHE,
3760 : MF_MSG_CLEAN_SWAPCACHE,
3761 : MF_MSG_DIRTY_MLOCKED_LRU,
3762 : MF_MSG_CLEAN_MLOCKED_LRU,
3763 : MF_MSG_DIRTY_UNEVICTABLE_LRU,
3764 : MF_MSG_CLEAN_UNEVICTABLE_LRU,
3765 : MF_MSG_DIRTY_LRU,
3766 : MF_MSG_CLEAN_LRU,
3767 : MF_MSG_TRUNCATED_LRU,
3768 : MF_MSG_BUDDY,
3769 : MF_MSG_DAX,
3770 : MF_MSG_UNSPLIT_THP,
3771 : MF_MSG_UNKNOWN,
3772 : };
3773 :
3774 : #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
3775 : extern void clear_huge_page(struct page *page,
3776 : unsigned long addr_hint,
3777 : unsigned int pages_per_huge_page);
3778 : int copy_user_large_folio(struct folio *dst, struct folio *src,
3779 : unsigned long addr_hint,
3780 : struct vm_area_struct *vma);
3781 : long copy_folio_from_user(struct folio *dst_folio,
3782 : const void __user *usr_src,
3783 : bool allow_pagefault);
3784 :
3785 : /**
3786 : * vma_is_special_huge - Are transhuge page-table entries considered special?
3787 : * @vma: Pointer to the struct vm_area_struct to consider
3788 : *
3789 : * Whether transhuge page-table entries are considered "special" following
3790 : * the definition in vm_normal_page().
3791 : *
3792 : * Return: true if transhuge page-table entries should be considered special,
3793 : * false otherwise.
3794 : */
3795 : static inline bool vma_is_special_huge(const struct vm_area_struct *vma)
3796 : {
3797 : return vma_is_dax(vma) || (vma->vm_file &&
3798 : (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)));
3799 : }
3800 :
3801 : #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
3802 :
3803 : #if MAX_NUMNODES > 1
3804 : void __init setup_nr_node_ids(void);
3805 : #else
3806 : static inline void setup_nr_node_ids(void) {}
3807 : #endif
3808 :
3809 : extern int memcmp_pages(struct page *page1, struct page *page2);
3810 :
3811 : static inline int pages_identical(struct page *page1, struct page *page2)
3812 : {
3813 : return !memcmp_pages(page1, page2);
3814 : }
3815 :
3816 : #ifdef CONFIG_MAPPING_DIRTY_HELPERS
3817 : unsigned long clean_record_shared_mapping_range(struct address_space *mapping,
3818 : pgoff_t first_index, pgoff_t nr,
3819 : pgoff_t bitmap_pgoff,
3820 : unsigned long *bitmap,
3821 : pgoff_t *start,
3822 : pgoff_t *end);
3823 :
3824 : unsigned long wp_shared_mapping_range(struct address_space *mapping,
3825 : pgoff_t first_index, pgoff_t nr);
3826 : #endif
3827 :
3828 : extern int sysctl_nr_trim_pages;
3829 :
3830 : #ifdef CONFIG_PRINTK
3831 : void mem_dump_obj(void *object);
3832 : #else
3833 : static inline void mem_dump_obj(void *object) {}
3834 : #endif
3835 :
3836 : /**
3837 : * seal_check_future_write - Check for F_SEAL_FUTURE_WRITE flag and handle it
3838 : * @seals: the seals to check
3839 : * @vma: the vma to operate on
3840 : *
3841 : * Check whether F_SEAL_FUTURE_WRITE is set; if so, do proper check/handling on
3842 : * the vma flags. Return 0 if check pass, or <0 for errors.
3843 : */
3844 : static inline int seal_check_future_write(int seals, struct vm_area_struct *vma)
3845 : {
3846 0 : if (seals & F_SEAL_FUTURE_WRITE) {
3847 : /*
3848 : * New PROT_WRITE and MAP_SHARED mmaps are not allowed when
3849 : * "future write" seal active.
3850 : */
3851 0 : if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE))
3852 : return -EPERM;
3853 :
3854 : /*
3855 : * Since an F_SEAL_FUTURE_WRITE sealed memfd can be mapped as
3856 : * MAP_SHARED and read-only, take care to not allow mprotect to
3857 : * revert protections on such mappings. Do this only for shared
3858 : * mappings. For private mappings, don't need to mask
3859 : * VM_MAYWRITE as we still want them to be COW-writable.
3860 : */
3861 0 : if (vma->vm_flags & VM_SHARED)
3862 0 : vm_flags_clear(vma, VM_MAYWRITE);
3863 : }
3864 :
3865 : return 0;
3866 : }
3867 :
3868 : #ifdef CONFIG_ANON_VMA_NAME
3869 : int madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
3870 : unsigned long len_in,
3871 : struct anon_vma_name *anon_name);
3872 : #else
3873 : static inline int
3874 : madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
3875 : unsigned long len_in, struct anon_vma_name *anon_name) {
3876 : return 0;
3877 : }
3878 : #endif
3879 :
3880 : #ifdef CONFIG_UNACCEPTED_MEMORY
3881 :
3882 : bool range_contains_unaccepted_memory(phys_addr_t start, phys_addr_t end);
3883 : void accept_memory(phys_addr_t start, phys_addr_t end);
3884 :
3885 : #else
3886 :
3887 : static inline bool range_contains_unaccepted_memory(phys_addr_t start,
3888 : phys_addr_t end)
3889 : {
3890 : return false;
3891 : }
3892 :
3893 : static inline void accept_memory(phys_addr_t start, phys_addr_t end)
3894 : {
3895 : }
3896 :
3897 : #endif
3898 :
3899 : #endif /* _LINUX_MM_H */
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