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 :
33 : struct mempolicy;
34 : struct anon_vma;
35 : struct anon_vma_chain;
36 : struct user_struct;
37 : struct pt_regs;
38 :
39 : extern int sysctl_page_lock_unfairness;
40 :
41 : void init_mm_internals(void);
42 :
43 : #ifndef CONFIG_NUMA /* Don't use mapnrs, do it properly */
44 : extern unsigned long max_mapnr;
45 :
46 : static inline void set_max_mapnr(unsigned long limit)
47 : {
48 : max_mapnr = limit;
49 : }
50 : #else
51 : static inline void set_max_mapnr(unsigned long limit) { }
52 : #endif
53 :
54 : extern atomic_long_t _totalram_pages;
55 : static inline unsigned long totalram_pages(void)
56 : {
57 282 : return (unsigned long)atomic_long_read(&_totalram_pages);
58 : }
59 :
60 : static inline void totalram_pages_inc(void)
61 : {
62 0 : atomic_long_inc(&_totalram_pages);
63 : }
64 :
65 : static inline void totalram_pages_dec(void)
66 : {
67 : atomic_long_dec(&_totalram_pages);
68 : }
69 :
70 : static inline void totalram_pages_add(long count)
71 : {
72 1 : atomic_long_add(count, &_totalram_pages);
73 : }
74 :
75 : extern void * high_memory;
76 : extern int page_cluster;
77 : extern const int page_cluster_max;
78 :
79 : #ifdef CONFIG_SYSCTL
80 : extern int sysctl_legacy_va_layout;
81 : #else
82 : #define sysctl_legacy_va_layout 0
83 : #endif
84 :
85 : #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
86 : extern const int mmap_rnd_bits_min;
87 : extern const int mmap_rnd_bits_max;
88 : extern int mmap_rnd_bits __read_mostly;
89 : #endif
90 : #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
91 : extern const int mmap_rnd_compat_bits_min;
92 : extern const int mmap_rnd_compat_bits_max;
93 : extern int mmap_rnd_compat_bits __read_mostly;
94 : #endif
95 :
96 : #include <asm/page.h>
97 : #include <asm/processor.h>
98 :
99 : /*
100 : * Architectures that support memory tagging (assigning tags to memory regions,
101 : * embedding these tags into addresses that point to these memory regions, and
102 : * checking that the memory and the pointer tags match on memory accesses)
103 : * redefine this macro to strip tags from pointers.
104 : * It's defined as noop for architectures that don't support memory tagging.
105 : */
106 : #ifndef untagged_addr
107 : #define untagged_addr(addr) (addr)
108 : #endif
109 :
110 : #ifndef __pa_symbol
111 : #define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0))
112 : #endif
113 :
114 : #ifndef page_to_virt
115 : #define page_to_virt(x) __va(PFN_PHYS(page_to_pfn(x)))
116 : #endif
117 :
118 : #ifndef lm_alias
119 : #define lm_alias(x) __va(__pa_symbol(x))
120 : #endif
121 :
122 : /*
123 : * To prevent common memory management code establishing
124 : * a zero page mapping on a read fault.
125 : * This macro should be defined within <asm/pgtable.h>.
126 : * s390 does this to prevent multiplexing of hardware bits
127 : * related to the physical page in case of virtualization.
128 : */
129 : #ifndef mm_forbids_zeropage
130 : #define mm_forbids_zeropage(X) (0)
131 : #endif
132 :
133 : /*
134 : * On some architectures it is expensive to call memset() for small sizes.
135 : * If an architecture decides to implement their own version of
136 : * mm_zero_struct_page they should wrap the defines below in a #ifndef and
137 : * define their own version of this macro in <asm/pgtable.h>
138 : */
139 : #if BITS_PER_LONG == 64
140 : /* This function must be updated when the size of struct page grows above 96
141 : * or reduces below 56. The idea that compiler optimizes out switch()
142 : * statement, and only leaves move/store instructions. Also the compiler can
143 : * combine write statements if they are both assignments and can be reordered,
144 : * this can result in several of the writes here being dropped.
145 : */
146 : #define mm_zero_struct_page(pp) __mm_zero_struct_page(pp)
147 : static inline void __mm_zero_struct_page(struct page *page)
148 : {
149 262670 : unsigned long *_pp = (void *)page;
150 :
151 : /* Check that struct page is either 56, 64, 72, 80, 88 or 96 bytes */
152 : BUILD_BUG_ON(sizeof(struct page) & 7);
153 : BUILD_BUG_ON(sizeof(struct page) < 56);
154 : BUILD_BUG_ON(sizeof(struct page) > 96);
155 :
156 : switch (sizeof(struct page)) {
157 : case 96:
158 : _pp[11] = 0;
159 : fallthrough;
160 : case 88:
161 : _pp[10] = 0;
162 : fallthrough;
163 : case 80:
164 : _pp[9] = 0;
165 : fallthrough;
166 : case 72:
167 : _pp[8] = 0;
168 : fallthrough;
169 : case 64:
170 : _pp[7] = 0;
171 : fallthrough;
172 : case 56:
173 262670 : _pp[6] = 0;
174 262670 : _pp[5] = 0;
175 262670 : _pp[4] = 0;
176 262670 : _pp[3] = 0;
177 : _pp[2] = 0;
178 : _pp[1] = 0;
179 : _pp[0] = 0;
180 : }
181 : }
182 : #else
183 : #define mm_zero_struct_page(pp) ((void)memset((pp), 0, sizeof(struct page)))
184 : #endif
185 :
186 : /*
187 : * Default maximum number of active map areas, this limits the number of vmas
188 : * per mm struct. Users can overwrite this number by sysctl but there is a
189 : * problem.
190 : *
191 : * When a program's coredump is generated as ELF format, a section is created
192 : * per a vma. In ELF, the number of sections is represented in unsigned short.
193 : * This means the number of sections should be smaller than 65535 at coredump.
194 : * Because the kernel adds some informative sections to a image of program at
195 : * generating coredump, we need some margin. The number of extra sections is
196 : * 1-3 now and depends on arch. We use "5" as safe margin, here.
197 : *
198 : * ELF extended numbering allows more than 65535 sections, so 16-bit bound is
199 : * not a hard limit any more. Although some userspace tools can be surprised by
200 : * that.
201 : */
202 : #define MAPCOUNT_ELF_CORE_MARGIN (5)
203 : #define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
204 :
205 : extern int sysctl_max_map_count;
206 :
207 : extern unsigned long sysctl_user_reserve_kbytes;
208 : extern unsigned long sysctl_admin_reserve_kbytes;
209 :
210 : extern int sysctl_overcommit_memory;
211 : extern int sysctl_overcommit_ratio;
212 : extern unsigned long sysctl_overcommit_kbytes;
213 :
214 : int overcommit_ratio_handler(struct ctl_table *, int, void *, size_t *,
215 : loff_t *);
216 : int overcommit_kbytes_handler(struct ctl_table *, int, void *, size_t *,
217 : loff_t *);
218 : int overcommit_policy_handler(struct ctl_table *, int, void *, size_t *,
219 : loff_t *);
220 :
221 : #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
222 : #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
223 : #define folio_page_idx(folio, p) (page_to_pfn(p) - folio_pfn(folio))
224 : #else
225 : #define nth_page(page,n) ((page) + (n))
226 : #define folio_page_idx(folio, p) ((p) - &(folio)->page)
227 : #endif
228 :
229 : /* to align the pointer to the (next) page boundary */
230 : #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
231 :
232 : /* to align the pointer to the (prev) page boundary */
233 : #define PAGE_ALIGN_DOWN(addr) ALIGN_DOWN(addr, PAGE_SIZE)
234 :
235 : /* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
236 : #define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)(addr), PAGE_SIZE)
237 :
238 : #define lru_to_page(head) (list_entry((head)->prev, struct page, lru))
239 : static inline struct folio *lru_to_folio(struct list_head *head)
240 : {
241 0 : return list_entry((head)->prev, struct folio, lru);
242 : }
243 :
244 : void setup_initial_init_mm(void *start_code, void *end_code,
245 : void *end_data, void *brk);
246 :
247 : /*
248 : * Linux kernel virtual memory manager primitives.
249 : * The idea being to have a "virtual" mm in the same way
250 : * we have a virtual fs - giving a cleaner interface to the
251 : * mm details, and allowing different kinds of memory mappings
252 : * (from shared memory to executable loading to arbitrary
253 : * mmap() functions).
254 : */
255 :
256 : struct vm_area_struct *vm_area_alloc(struct mm_struct *);
257 : struct vm_area_struct *vm_area_dup(struct vm_area_struct *);
258 : void vm_area_free(struct vm_area_struct *);
259 :
260 : #ifndef CONFIG_MMU
261 : extern struct rb_root nommu_region_tree;
262 : extern struct rw_semaphore nommu_region_sem;
263 :
264 : extern unsigned int kobjsize(const void *objp);
265 : #endif
266 :
267 : /*
268 : * vm_flags in vm_area_struct, see mm_types.h.
269 : * When changing, update also include/trace/events/mmflags.h
270 : */
271 : #define VM_NONE 0x00000000
272 :
273 : #define VM_READ 0x00000001 /* currently active flags */
274 : #define VM_WRITE 0x00000002
275 : #define VM_EXEC 0x00000004
276 : #define VM_SHARED 0x00000008
277 :
278 : /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
279 : #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */
280 : #define VM_MAYWRITE 0x00000020
281 : #define VM_MAYEXEC 0x00000040
282 : #define VM_MAYSHARE 0x00000080
283 :
284 : #define VM_GROWSDOWN 0x00000100 /* general info on the segment */
285 : #ifdef CONFIG_MMU
286 : #define VM_UFFD_MISSING 0x00000200 /* missing pages tracking */
287 : #else /* CONFIG_MMU */
288 : #define VM_MAYOVERLAY 0x00000200 /* nommu: R/O MAP_PRIVATE mapping that might overlay a file mapping */
289 : #define VM_UFFD_MISSING 0
290 : #endif /* CONFIG_MMU */
291 : #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */
292 : #define VM_UFFD_WP 0x00001000 /* wrprotect pages tracking */
293 :
294 : #define VM_LOCKED 0x00002000
295 : #define VM_IO 0x00004000 /* Memory mapped I/O or similar */
296 :
297 : /* Used by sys_madvise() */
298 : #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */
299 : #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */
300 :
301 : #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */
302 : #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */
303 : #define VM_LOCKONFAULT 0x00080000 /* Lock the pages covered when they are faulted in */
304 : #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */
305 : #define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */
306 : #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */
307 : #define VM_SYNC 0x00800000 /* Synchronous page faults */
308 : #define VM_ARCH_1 0x01000000 /* Architecture-specific flag */
309 : #define VM_WIPEONFORK 0x02000000 /* Wipe VMA contents in child. */
310 : #define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */
311 :
312 : #ifdef CONFIG_MEM_SOFT_DIRTY
313 : # define VM_SOFTDIRTY 0x08000000 /* Not soft dirty clean area */
314 : #else
315 : # define VM_SOFTDIRTY 0
316 : #endif
317 :
318 : #define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */
319 : #define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */
320 : #define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */
321 : #define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */
322 :
323 : #ifdef CONFIG_ARCH_USES_HIGH_VMA_FLAGS
324 : #define VM_HIGH_ARCH_BIT_0 32 /* bit only usable on 64-bit architectures */
325 : #define VM_HIGH_ARCH_BIT_1 33 /* bit only usable on 64-bit architectures */
326 : #define VM_HIGH_ARCH_BIT_2 34 /* bit only usable on 64-bit architectures */
327 : #define VM_HIGH_ARCH_BIT_3 35 /* bit only usable on 64-bit architectures */
328 : #define VM_HIGH_ARCH_BIT_4 36 /* bit only usable on 64-bit architectures */
329 : #define VM_HIGH_ARCH_0 BIT(VM_HIGH_ARCH_BIT_0)
330 : #define VM_HIGH_ARCH_1 BIT(VM_HIGH_ARCH_BIT_1)
331 : #define VM_HIGH_ARCH_2 BIT(VM_HIGH_ARCH_BIT_2)
332 : #define VM_HIGH_ARCH_3 BIT(VM_HIGH_ARCH_BIT_3)
333 : #define VM_HIGH_ARCH_4 BIT(VM_HIGH_ARCH_BIT_4)
334 : #endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */
335 :
336 : #ifdef CONFIG_ARCH_HAS_PKEYS
337 : # define VM_PKEY_SHIFT VM_HIGH_ARCH_BIT_0
338 : # define VM_PKEY_BIT0 VM_HIGH_ARCH_0 /* A protection key is a 4-bit value */
339 : # define VM_PKEY_BIT1 VM_HIGH_ARCH_1 /* on x86 and 5-bit value on ppc64 */
340 : # define VM_PKEY_BIT2 VM_HIGH_ARCH_2
341 : # define VM_PKEY_BIT3 VM_HIGH_ARCH_3
342 : #ifdef CONFIG_PPC
343 : # define VM_PKEY_BIT4 VM_HIGH_ARCH_4
344 : #else
345 : # define VM_PKEY_BIT4 0
346 : #endif
347 : #endif /* CONFIG_ARCH_HAS_PKEYS */
348 :
349 : #if defined(CONFIG_X86)
350 : # define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */
351 : #elif defined(CONFIG_PPC)
352 : # define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */
353 : #elif defined(CONFIG_PARISC)
354 : # define VM_GROWSUP VM_ARCH_1
355 : #elif defined(CONFIG_IA64)
356 : # define VM_GROWSUP VM_ARCH_1
357 : #elif defined(CONFIG_SPARC64)
358 : # define VM_SPARC_ADI VM_ARCH_1 /* Uses ADI tag for access control */
359 : # define VM_ARCH_CLEAR VM_SPARC_ADI
360 : #elif defined(CONFIG_ARM64)
361 : # define VM_ARM64_BTI VM_ARCH_1 /* BTI guarded page, a.k.a. GP bit */
362 : # define VM_ARCH_CLEAR VM_ARM64_BTI
363 : #elif !defined(CONFIG_MMU)
364 : # define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */
365 : #endif
366 :
367 : #if defined(CONFIG_ARM64_MTE)
368 : # define VM_MTE VM_HIGH_ARCH_0 /* Use Tagged memory for access control */
369 : # define VM_MTE_ALLOWED VM_HIGH_ARCH_1 /* Tagged memory permitted */
370 : #else
371 : # define VM_MTE VM_NONE
372 : # define VM_MTE_ALLOWED VM_NONE
373 : #endif
374 :
375 : #ifndef VM_GROWSUP
376 : # define VM_GROWSUP VM_NONE
377 : #endif
378 :
379 : #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
380 : # define VM_UFFD_MINOR_BIT 37
381 : # define VM_UFFD_MINOR BIT(VM_UFFD_MINOR_BIT) /* UFFD minor faults */
382 : #else /* !CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
383 : # define VM_UFFD_MINOR VM_NONE
384 : #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
385 :
386 : /* Bits set in the VMA until the stack is in its final location */
387 : #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ)
388 :
389 : #define TASK_EXEC ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0)
390 :
391 : /* Common data flag combinations */
392 : #define VM_DATA_FLAGS_TSK_EXEC (VM_READ | VM_WRITE | TASK_EXEC | \
393 : VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
394 : #define VM_DATA_FLAGS_NON_EXEC (VM_READ | VM_WRITE | VM_MAYREAD | \
395 : VM_MAYWRITE | VM_MAYEXEC)
396 : #define VM_DATA_FLAGS_EXEC (VM_READ | VM_WRITE | VM_EXEC | \
397 : VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
398 :
399 : #ifndef VM_DATA_DEFAULT_FLAGS /* arch can override this */
400 : #define VM_DATA_DEFAULT_FLAGS VM_DATA_FLAGS_EXEC
401 : #endif
402 :
403 : #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */
404 : #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
405 : #endif
406 :
407 : #ifdef CONFIG_STACK_GROWSUP
408 : #define VM_STACK VM_GROWSUP
409 : #else
410 : #define VM_STACK VM_GROWSDOWN
411 : #endif
412 :
413 : #define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
414 :
415 : /* VMA basic access permission flags */
416 : #define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC)
417 :
418 :
419 : /*
420 : * Special vmas that are non-mergable, non-mlock()able.
421 : */
422 : #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP)
423 :
424 : /* This mask prevents VMA from being scanned with khugepaged */
425 : #define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB)
426 :
427 : /* This mask defines which mm->def_flags a process can inherit its parent */
428 : #define VM_INIT_DEF_MASK VM_NOHUGEPAGE
429 :
430 : /* This mask represents all the VMA flag bits used by mlock */
431 : #define VM_LOCKED_MASK (VM_LOCKED | VM_LOCKONFAULT)
432 :
433 : /* Arch-specific flags to clear when updating VM flags on protection change */
434 : #ifndef VM_ARCH_CLEAR
435 : # define VM_ARCH_CLEAR VM_NONE
436 : #endif
437 : #define VM_FLAGS_CLEAR (ARCH_VM_PKEY_FLAGS | VM_ARCH_CLEAR)
438 :
439 : /*
440 : * mapping from the currently active vm_flags protection bits (the
441 : * low four bits) to a page protection mask..
442 : */
443 :
444 : /*
445 : * The default fault flags that should be used by most of the
446 : * arch-specific page fault handlers.
447 : */
448 : #define FAULT_FLAG_DEFAULT (FAULT_FLAG_ALLOW_RETRY | \
449 : FAULT_FLAG_KILLABLE | \
450 : FAULT_FLAG_INTERRUPTIBLE)
451 :
452 : /**
453 : * fault_flag_allow_retry_first - check ALLOW_RETRY the first time
454 : * @flags: Fault flags.
455 : *
456 : * This is mostly used for places where we want to try to avoid taking
457 : * the mmap_lock for too long a time when waiting for another condition
458 : * to change, in which case we can try to be polite to release the
459 : * mmap_lock in the first round to avoid potential starvation of other
460 : * processes that would also want the mmap_lock.
461 : *
462 : * Return: true if the page fault allows retry and this is the first
463 : * attempt of the fault handling; false otherwise.
464 : */
465 : static inline bool fault_flag_allow_retry_first(enum fault_flag flags)
466 : {
467 0 : return (flags & FAULT_FLAG_ALLOW_RETRY) &&
468 : (!(flags & FAULT_FLAG_TRIED));
469 : }
470 :
471 : #define FAULT_FLAG_TRACE \
472 : { FAULT_FLAG_WRITE, "WRITE" }, \
473 : { FAULT_FLAG_MKWRITE, "MKWRITE" }, \
474 : { FAULT_FLAG_ALLOW_RETRY, "ALLOW_RETRY" }, \
475 : { FAULT_FLAG_RETRY_NOWAIT, "RETRY_NOWAIT" }, \
476 : { FAULT_FLAG_KILLABLE, "KILLABLE" }, \
477 : { FAULT_FLAG_TRIED, "TRIED" }, \
478 : { FAULT_FLAG_USER, "USER" }, \
479 : { FAULT_FLAG_REMOTE, "REMOTE" }, \
480 : { FAULT_FLAG_INSTRUCTION, "INSTRUCTION" }, \
481 : { FAULT_FLAG_INTERRUPTIBLE, "INTERRUPTIBLE" }
482 :
483 : /*
484 : * vm_fault is filled by the pagefault handler and passed to the vma's
485 : * ->fault function. The vma's ->fault is responsible for returning a bitmask
486 : * of VM_FAULT_xxx flags that give details about how the fault was handled.
487 : *
488 : * MM layer fills up gfp_mask for page allocations but fault handler might
489 : * alter it if its implementation requires a different allocation context.
490 : *
491 : * pgoff should be used in favour of virtual_address, if possible.
492 : */
493 : struct vm_fault {
494 : const struct {
495 : struct vm_area_struct *vma; /* Target VMA */
496 : gfp_t gfp_mask; /* gfp mask to be used for allocations */
497 : pgoff_t pgoff; /* Logical page offset based on vma */
498 : unsigned long address; /* Faulting virtual address - masked */
499 : unsigned long real_address; /* Faulting virtual address - unmasked */
500 : };
501 : enum fault_flag flags; /* FAULT_FLAG_xxx flags
502 : * XXX: should really be 'const' */
503 : pmd_t *pmd; /* Pointer to pmd entry matching
504 : * the 'address' */
505 : pud_t *pud; /* Pointer to pud entry matching
506 : * the 'address'
507 : */
508 : union {
509 : pte_t orig_pte; /* Value of PTE at the time of fault */
510 : pmd_t orig_pmd; /* Value of PMD at the time of fault,
511 : * used by PMD fault only.
512 : */
513 : };
514 :
515 : struct page *cow_page; /* Page handler may use for COW fault */
516 : struct page *page; /* ->fault handlers should return a
517 : * page here, unless VM_FAULT_NOPAGE
518 : * is set (which is also implied by
519 : * VM_FAULT_ERROR).
520 : */
521 : /* These three entries are valid only while holding ptl lock */
522 : pte_t *pte; /* Pointer to pte entry matching
523 : * the 'address'. NULL if the page
524 : * table hasn't been allocated.
525 : */
526 : spinlock_t *ptl; /* Page table lock.
527 : * Protects pte page table if 'pte'
528 : * is not NULL, otherwise pmd.
529 : */
530 : pgtable_t prealloc_pte; /* Pre-allocated pte page table.
531 : * vm_ops->map_pages() sets up a page
532 : * table from atomic context.
533 : * do_fault_around() pre-allocates
534 : * page table to avoid allocation from
535 : * atomic context.
536 : */
537 : };
538 :
539 : /* page entry size for vm->huge_fault() */
540 : enum page_entry_size {
541 : PE_SIZE_PTE = 0,
542 : PE_SIZE_PMD,
543 : PE_SIZE_PUD,
544 : };
545 :
546 : /*
547 : * These are the virtual MM functions - opening of an area, closing and
548 : * unmapping it (needed to keep files on disk up-to-date etc), pointer
549 : * to the functions called when a no-page or a wp-page exception occurs.
550 : */
551 : struct vm_operations_struct {
552 : void (*open)(struct vm_area_struct * area);
553 : /**
554 : * @close: Called when the VMA is being removed from the MM.
555 : * Context: User context. May sleep. Caller holds mmap_lock.
556 : */
557 : void (*close)(struct vm_area_struct * area);
558 : /* Called any time before splitting to check if it's allowed */
559 : int (*may_split)(struct vm_area_struct *area, unsigned long addr);
560 : int (*mremap)(struct vm_area_struct *area);
561 : /*
562 : * Called by mprotect() to make driver-specific permission
563 : * checks before mprotect() is finalised. The VMA must not
564 : * be modified. Returns 0 if mprotect() can proceed.
565 : */
566 : int (*mprotect)(struct vm_area_struct *vma, unsigned long start,
567 : unsigned long end, unsigned long newflags);
568 : vm_fault_t (*fault)(struct vm_fault *vmf);
569 : vm_fault_t (*huge_fault)(struct vm_fault *vmf,
570 : enum page_entry_size pe_size);
571 : vm_fault_t (*map_pages)(struct vm_fault *vmf,
572 : pgoff_t start_pgoff, pgoff_t end_pgoff);
573 : unsigned long (*pagesize)(struct vm_area_struct * area);
574 :
575 : /* notification that a previously read-only page is about to become
576 : * writable, if an error is returned it will cause a SIGBUS */
577 : vm_fault_t (*page_mkwrite)(struct vm_fault *vmf);
578 :
579 : /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */
580 : vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf);
581 :
582 : /* called by access_process_vm when get_user_pages() fails, typically
583 : * for use by special VMAs. See also generic_access_phys() for a generic
584 : * implementation useful for any iomem mapping.
585 : */
586 : int (*access)(struct vm_area_struct *vma, unsigned long addr,
587 : void *buf, int len, int write);
588 :
589 : /* Called by the /proc/PID/maps code to ask the vma whether it
590 : * has a special name. Returning non-NULL will also cause this
591 : * vma to be dumped unconditionally. */
592 : const char *(*name)(struct vm_area_struct *vma);
593 :
594 : #ifdef CONFIG_NUMA
595 : /*
596 : * set_policy() op must add a reference to any non-NULL @new mempolicy
597 : * to hold the policy upon return. Caller should pass NULL @new to
598 : * remove a policy and fall back to surrounding context--i.e. do not
599 : * install a MPOL_DEFAULT policy, nor the task or system default
600 : * mempolicy.
601 : */
602 : int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
603 :
604 : /*
605 : * get_policy() op must add reference [mpol_get()] to any policy at
606 : * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure
607 : * in mm/mempolicy.c will do this automatically.
608 : * get_policy() must NOT add a ref if the policy at (vma,addr) is not
609 : * marked as MPOL_SHARED. vma policies are protected by the mmap_lock.
610 : * If no [shared/vma] mempolicy exists at the addr, get_policy() op
611 : * must return NULL--i.e., do not "fallback" to task or system default
612 : * policy.
613 : */
614 : struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
615 : unsigned long addr);
616 : #endif
617 : /*
618 : * Called by vm_normal_page() for special PTEs to find the
619 : * page for @addr. This is useful if the default behavior
620 : * (using pte_page()) would not find the correct page.
621 : */
622 : struct page *(*find_special_page)(struct vm_area_struct *vma,
623 : unsigned long addr);
624 : };
625 :
626 : static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm)
627 : {
628 : static const struct vm_operations_struct dummy_vm_ops = {};
629 :
630 0 : memset(vma, 0, sizeof(*vma));
631 0 : vma->vm_mm = mm;
632 0 : vma->vm_ops = &dummy_vm_ops;
633 0 : INIT_LIST_HEAD(&vma->anon_vma_chain);
634 : }
635 :
636 : /* Use when VMA is not part of the VMA tree and needs no locking */
637 : static inline void vm_flags_init(struct vm_area_struct *vma,
638 : vm_flags_t flags)
639 : {
640 0 : ACCESS_PRIVATE(vma, __vm_flags) = flags;
641 : }
642 :
643 : /* Use when VMA is part of the VMA tree and modifications need coordination */
644 : static inline void vm_flags_reset(struct vm_area_struct *vma,
645 : vm_flags_t flags)
646 : {
647 0 : mmap_assert_write_locked(vma->vm_mm);
648 0 : vm_flags_init(vma, flags);
649 : }
650 :
651 : static inline void vm_flags_reset_once(struct vm_area_struct *vma,
652 : vm_flags_t flags)
653 : {
654 0 : mmap_assert_write_locked(vma->vm_mm);
655 0 : WRITE_ONCE(ACCESS_PRIVATE(vma, __vm_flags), flags);
656 : }
657 :
658 : static inline void vm_flags_set(struct vm_area_struct *vma,
659 : vm_flags_t flags)
660 : {
661 0 : mmap_assert_write_locked(vma->vm_mm);
662 0 : ACCESS_PRIVATE(vma, __vm_flags) |= flags;
663 : }
664 :
665 : static inline void vm_flags_clear(struct vm_area_struct *vma,
666 : vm_flags_t flags)
667 : {
668 0 : mmap_assert_write_locked(vma->vm_mm);
669 0 : ACCESS_PRIVATE(vma, __vm_flags) &= ~flags;
670 : }
671 :
672 : /*
673 : * Use only if VMA is not part of the VMA tree or has no other users and
674 : * therefore needs no locking.
675 : */
676 : static inline void __vm_flags_mod(struct vm_area_struct *vma,
677 : vm_flags_t set, vm_flags_t clear)
678 : {
679 : vm_flags_init(vma, (vma->vm_flags | set) & ~clear);
680 : }
681 :
682 : /*
683 : * Use only when the order of set/clear operations is unimportant, otherwise
684 : * use vm_flags_{set|clear} explicitly.
685 : */
686 : static inline void vm_flags_mod(struct vm_area_struct *vma,
687 : vm_flags_t set, vm_flags_t clear)
688 : {
689 : mmap_assert_write_locked(vma->vm_mm);
690 : __vm_flags_mod(vma, set, clear);
691 : }
692 :
693 : static inline void vma_set_anonymous(struct vm_area_struct *vma)
694 : {
695 0 : vma->vm_ops = NULL;
696 : }
697 :
698 : static inline bool vma_is_anonymous(struct vm_area_struct *vma)
699 : {
700 0 : return !vma->vm_ops;
701 : }
702 :
703 : static inline bool vma_is_temporary_stack(struct vm_area_struct *vma)
704 : {
705 0 : int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP);
706 :
707 0 : if (!maybe_stack)
708 : return false;
709 :
710 0 : if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) ==
711 : VM_STACK_INCOMPLETE_SETUP)
712 : return true;
713 :
714 : return false;
715 : }
716 :
717 : static inline bool vma_is_foreign(struct vm_area_struct *vma)
718 : {
719 : if (!current->mm)
720 : return true;
721 :
722 : if (current->mm != vma->vm_mm)
723 : return true;
724 :
725 : return false;
726 : }
727 :
728 : static inline bool vma_is_accessible(struct vm_area_struct *vma)
729 : {
730 0 : return vma->vm_flags & VM_ACCESS_FLAGS;
731 : }
732 :
733 : static inline
734 : struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max)
735 : {
736 0 : return mas_find(&vmi->mas, max - 1);
737 : }
738 :
739 : static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi)
740 : {
741 : /*
742 : * Uses mas_find() to get the first VMA when the iterator starts.
743 : * Calling mas_next() could skip the first entry.
744 : */
745 0 : return mas_find(&vmi->mas, ULONG_MAX);
746 : }
747 :
748 : static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi)
749 : {
750 0 : return mas_prev(&vmi->mas, 0);
751 : }
752 :
753 : static inline unsigned long vma_iter_addr(struct vma_iterator *vmi)
754 : {
755 : return vmi->mas.index;
756 : }
757 :
758 : static inline unsigned long vma_iter_end(struct vma_iterator *vmi)
759 : {
760 0 : return vmi->mas.last + 1;
761 : }
762 : static inline int vma_iter_bulk_alloc(struct vma_iterator *vmi,
763 : unsigned long count)
764 : {
765 0 : return mas_expected_entries(&vmi->mas, count);
766 : }
767 :
768 : /* Free any unused preallocations */
769 : static inline void vma_iter_free(struct vma_iterator *vmi)
770 : {
771 0 : mas_destroy(&vmi->mas);
772 : }
773 :
774 0 : static inline int vma_iter_bulk_store(struct vma_iterator *vmi,
775 : struct vm_area_struct *vma)
776 : {
777 0 : vmi->mas.index = vma->vm_start;
778 0 : vmi->mas.last = vma->vm_end - 1;
779 0 : mas_store(&vmi->mas, vma);
780 0 : if (unlikely(mas_is_err(&vmi->mas)))
781 : return -ENOMEM;
782 :
783 0 : return 0;
784 : }
785 :
786 : static inline void vma_iter_invalidate(struct vma_iterator *vmi)
787 : {
788 0 : mas_pause(&vmi->mas);
789 : }
790 :
791 : static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr)
792 : {
793 0 : mas_set(&vmi->mas, addr);
794 : }
795 :
796 : #define for_each_vma(__vmi, __vma) \
797 : while (((__vma) = vma_next(&(__vmi))) != NULL)
798 :
799 : /* The MM code likes to work with exclusive end addresses */
800 : #define for_each_vma_range(__vmi, __vma, __end) \
801 : while (((__vma) = vma_find(&(__vmi), (__end))) != NULL)
802 :
803 : #ifdef CONFIG_SHMEM
804 : /*
805 : * The vma_is_shmem is not inline because it is used only by slow
806 : * paths in userfault.
807 : */
808 : bool vma_is_shmem(struct vm_area_struct *vma);
809 : bool vma_is_anon_shmem(struct vm_area_struct *vma);
810 : #else
811 : static inline bool vma_is_shmem(struct vm_area_struct *vma) { return false; }
812 : static inline bool vma_is_anon_shmem(struct vm_area_struct *vma) { return false; }
813 : #endif
814 :
815 : int vma_is_stack_for_current(struct vm_area_struct *vma);
816 :
817 : /* flush_tlb_range() takes a vma, not a mm, and can care about flags */
818 : #define TLB_FLUSH_VMA(mm,flags) { .vm_mm = (mm), .vm_flags = (flags) }
819 :
820 : struct mmu_gather;
821 : struct inode;
822 :
823 : /*
824 : * compound_order() can be called without holding a reference, which means
825 : * that niceties like page_folio() don't work. These callers should be
826 : * prepared to handle wild return values. For example, PG_head may be
827 : * set before _folio_order is initialised, or this may be a tail page.
828 : * See compaction.c for some good examples.
829 : */
830 : static inline unsigned int compound_order(struct page *page)
831 : {
832 0 : struct folio *folio = (struct folio *)page;
833 :
834 0 : if (!test_bit(PG_head, &folio->flags))
835 : return 0;
836 0 : return folio->_folio_order;
837 : }
838 :
839 : /**
840 : * folio_order - The allocation order of a folio.
841 : * @folio: The folio.
842 : *
843 : * A folio is composed of 2^order pages. See get_order() for the definition
844 : * of order.
845 : *
846 : * Return: The order of the folio.
847 : */
848 : static inline unsigned int folio_order(struct folio *folio)
849 : {
850 8166 : if (!folio_test_large(folio))
851 : return 0;
852 6 : return folio->_folio_order;
853 : }
854 :
855 : #include <linux/huge_mm.h>
856 :
857 : /*
858 : * Methods to modify the page usage count.
859 : *
860 : * What counts for a page usage:
861 : * - cache mapping (page->mapping)
862 : * - private data (page->private)
863 : * - page mapped in a task's page tables, each mapping
864 : * is counted separately
865 : *
866 : * Also, many kernel routines increase the page count before a critical
867 : * routine so they can be sure the page doesn't go away from under them.
868 : */
869 :
870 : /*
871 : * Drop a ref, return true if the refcount fell to zero (the page has no users)
872 : */
873 : static inline int put_page_testzero(struct page *page)
874 : {
875 : VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
876 50643 : return page_ref_dec_and_test(page);
877 : }
878 :
879 : static inline int folio_put_testzero(struct folio *folio)
880 : {
881 0 : return put_page_testzero(&folio->page);
882 : }
883 :
884 : /*
885 : * Try to grab a ref unless the page has a refcount of zero, return false if
886 : * that is the case.
887 : * This can be called when MMU is off so it must not access
888 : * any of the virtual mappings.
889 : */
890 : static inline bool get_page_unless_zero(struct page *page)
891 : {
892 0 : return page_ref_add_unless(page, 1, 0);
893 : }
894 :
895 : static inline struct folio *folio_get_nontail_page(struct page *page)
896 : {
897 0 : if (unlikely(!get_page_unless_zero(page)))
898 : return NULL;
899 : return (struct folio *)page;
900 : }
901 :
902 : extern int page_is_ram(unsigned long pfn);
903 :
904 : enum {
905 : REGION_INTERSECTS,
906 : REGION_DISJOINT,
907 : REGION_MIXED,
908 : };
909 :
910 : int region_intersects(resource_size_t offset, size_t size, unsigned long flags,
911 : unsigned long desc);
912 :
913 : /* Support for virtually mapped pages */
914 : struct page *vmalloc_to_page(const void *addr);
915 : unsigned long vmalloc_to_pfn(const void *addr);
916 :
917 : /*
918 : * Determine if an address is within the vmalloc range
919 : *
920 : * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
921 : * is no special casing required.
922 : */
923 :
924 : #ifndef is_ioremap_addr
925 : #define is_ioremap_addr(x) is_vmalloc_addr(x)
926 : #endif
927 :
928 : #ifdef CONFIG_MMU
929 : extern bool is_vmalloc_addr(const void *x);
930 : extern int is_vmalloc_or_module_addr(const void *x);
931 : #else
932 : static inline bool is_vmalloc_addr(const void *x)
933 : {
934 : return false;
935 : }
936 : static inline int is_vmalloc_or_module_addr(const void *x)
937 : {
938 : return 0;
939 : }
940 : #endif
941 :
942 : /*
943 : * How many times the entire folio is mapped as a single unit (eg by a
944 : * PMD or PUD entry). This is probably not what you want, except for
945 : * debugging purposes - it does not include PTE-mapped sub-pages; look
946 : * at folio_mapcount() or page_mapcount() or total_mapcount() instead.
947 : */
948 : static inline int folio_entire_mapcount(struct folio *folio)
949 : {
950 : VM_BUG_ON_FOLIO(!folio_test_large(folio), folio);
951 0 : return atomic_read(&folio->_entire_mapcount) + 1;
952 : }
953 :
954 : /*
955 : * The atomic page->_mapcount, starts from -1: so that transitions
956 : * both from it and to it can be tracked, using atomic_inc_and_test
957 : * and atomic_add_negative(-1).
958 : */
959 : static inline void page_mapcount_reset(struct page *page)
960 : {
961 525340 : atomic_set(&(page)->_mapcount, -1);
962 : }
963 :
964 : /**
965 : * page_mapcount() - Number of times this precise page is mapped.
966 : * @page: The page.
967 : *
968 : * The number of times this page is mapped. If this page is part of
969 : * a large folio, it includes the number of times this page is mapped
970 : * as part of that folio.
971 : *
972 : * The result is undefined for pages which cannot be mapped into userspace.
973 : * For example SLAB or special types of pages. See function page_has_type().
974 : * They use this field in struct page differently.
975 : */
976 0 : static inline int page_mapcount(struct page *page)
977 : {
978 0 : int mapcount = atomic_read(&page->_mapcount) + 1;
979 :
980 0 : if (unlikely(PageCompound(page)))
981 0 : mapcount += folio_entire_mapcount(page_folio(page));
982 :
983 0 : return mapcount;
984 : }
985 :
986 : int folio_total_mapcount(struct folio *folio);
987 :
988 : /**
989 : * folio_mapcount() - Calculate the number of mappings of this folio.
990 : * @folio: The folio.
991 : *
992 : * A large folio tracks both how many times the entire folio is mapped,
993 : * and how many times each individual page in the folio is mapped.
994 : * This function calculates the total number of times the folio is
995 : * mapped.
996 : *
997 : * Return: The number of times this folio is mapped.
998 : */
999 : static inline int folio_mapcount(struct folio *folio)
1000 : {
1001 0 : if (likely(!folio_test_large(folio)))
1002 0 : return atomic_read(&folio->_mapcount) + 1;
1003 0 : return folio_total_mapcount(folio);
1004 : }
1005 :
1006 0 : static inline int total_mapcount(struct page *page)
1007 : {
1008 0 : if (likely(!PageCompound(page)))
1009 0 : return atomic_read(&page->_mapcount) + 1;
1010 0 : return folio_total_mapcount(page_folio(page));
1011 : }
1012 :
1013 : static inline bool folio_large_is_mapped(struct folio *folio)
1014 : {
1015 : /*
1016 : * Reading _entire_mapcount below could be omitted if hugetlb
1017 : * participated in incrementing nr_pages_mapped when compound mapped.
1018 : */
1019 0 : return atomic_read(&folio->_nr_pages_mapped) > 0 ||
1020 0 : atomic_read(&folio->_entire_mapcount) >= 0;
1021 : }
1022 :
1023 : /**
1024 : * folio_mapped - Is this folio mapped into userspace?
1025 : * @folio: The folio.
1026 : *
1027 : * Return: True if any page in this folio is referenced by user page tables.
1028 : */
1029 : static inline bool folio_mapped(struct folio *folio)
1030 : {
1031 0 : if (likely(!folio_test_large(folio)))
1032 0 : return atomic_read(&folio->_mapcount) >= 0;
1033 0 : return folio_large_is_mapped(folio);
1034 : }
1035 :
1036 : /*
1037 : * Return true if this page is mapped into pagetables.
1038 : * For compound page it returns true if any sub-page of compound page is mapped,
1039 : * even if this particular sub-page is not itself mapped by any PTE or PMD.
1040 : */
1041 0 : static inline bool page_mapped(struct page *page)
1042 : {
1043 0 : if (likely(!PageCompound(page)))
1044 0 : return atomic_read(&page->_mapcount) >= 0;
1045 0 : return folio_large_is_mapped(page_folio(page));
1046 : }
1047 :
1048 : static inline struct page *virt_to_head_page(const void *x)
1049 : {
1050 0 : struct page *page = virt_to_page(x);
1051 :
1052 0 : return compound_head(page);
1053 : }
1054 :
1055 : static inline struct folio *virt_to_folio(const void *x)
1056 : {
1057 902618 : struct page *page = virt_to_page(x);
1058 :
1059 451309 : return page_folio(page);
1060 : }
1061 :
1062 : void __folio_put(struct folio *folio);
1063 :
1064 : void put_pages_list(struct list_head *pages);
1065 :
1066 : void split_page(struct page *page, unsigned int order);
1067 : void folio_copy(struct folio *dst, struct folio *src);
1068 :
1069 : unsigned long nr_free_buffer_pages(void);
1070 :
1071 : /*
1072 : * Compound pages have a destructor function. Provide a
1073 : * prototype for that function and accessor functions.
1074 : * These are _only_ valid on the head of a compound page.
1075 : */
1076 : typedef void compound_page_dtor(struct page *);
1077 :
1078 : /* Keep the enum in sync with compound_page_dtors array in mm/page_alloc.c */
1079 : enum compound_dtor_id {
1080 : NULL_COMPOUND_DTOR,
1081 : COMPOUND_PAGE_DTOR,
1082 : #ifdef CONFIG_HUGETLB_PAGE
1083 : HUGETLB_PAGE_DTOR,
1084 : #endif
1085 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1086 : TRANSHUGE_PAGE_DTOR,
1087 : #endif
1088 : NR_COMPOUND_DTORS,
1089 : };
1090 : extern compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS];
1091 :
1092 : static inline void set_compound_page_dtor(struct page *page,
1093 : enum compound_dtor_id compound_dtor)
1094 : {
1095 102 : struct folio *folio = (struct folio *)page;
1096 :
1097 : VM_BUG_ON_PAGE(compound_dtor >= NR_COMPOUND_DTORS, page);
1098 : VM_BUG_ON_PAGE(!PageHead(page), page);
1099 102 : folio->_folio_dtor = compound_dtor;
1100 : }
1101 :
1102 : static inline void folio_set_compound_dtor(struct folio *folio,
1103 : enum compound_dtor_id compound_dtor)
1104 : {
1105 : VM_BUG_ON_FOLIO(compound_dtor >= NR_COMPOUND_DTORS, folio);
1106 : folio->_folio_dtor = compound_dtor;
1107 : }
1108 :
1109 : void destroy_large_folio(struct folio *folio);
1110 :
1111 : static inline void set_compound_order(struct page *page, unsigned int order)
1112 : {
1113 102 : struct folio *folio = (struct folio *)page;
1114 :
1115 102 : folio->_folio_order = order;
1116 : #ifdef CONFIG_64BIT
1117 102 : folio->_folio_nr_pages = 1U << order;
1118 : #endif
1119 : }
1120 :
1121 : /* Returns the number of bytes in this potentially compound page. */
1122 : static inline unsigned long page_size(struct page *page)
1123 : {
1124 0 : return PAGE_SIZE << compound_order(page);
1125 : }
1126 :
1127 : /* Returns the number of bits needed for the number of bytes in a page */
1128 : static inline unsigned int page_shift(struct page *page)
1129 : {
1130 : return PAGE_SHIFT + compound_order(page);
1131 : }
1132 :
1133 : /**
1134 : * thp_order - Order of a transparent huge page.
1135 : * @page: Head page of a transparent huge page.
1136 : */
1137 : static inline unsigned int thp_order(struct page *page)
1138 : {
1139 : VM_BUG_ON_PGFLAGS(PageTail(page), page);
1140 0 : return compound_order(page);
1141 : }
1142 :
1143 : /**
1144 : * thp_size - Size of a transparent huge page.
1145 : * @page: Head page of a transparent huge page.
1146 : *
1147 : * Return: Number of bytes in this page.
1148 : */
1149 : static inline unsigned long thp_size(struct page *page)
1150 : {
1151 0 : return PAGE_SIZE << thp_order(page);
1152 : }
1153 :
1154 : void free_compound_page(struct page *page);
1155 :
1156 : #ifdef CONFIG_MMU
1157 : /*
1158 : * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when
1159 : * servicing faults for write access. In the normal case, do always want
1160 : * pte_mkwrite. But get_user_pages can cause write faults for mappings
1161 : * that do not have writing enabled, when used by access_process_vm.
1162 : */
1163 : static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
1164 : {
1165 0 : if (likely(vma->vm_flags & VM_WRITE))
1166 : pte = pte_mkwrite(pte);
1167 : return pte;
1168 : }
1169 :
1170 : vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page);
1171 : void do_set_pte(struct vm_fault *vmf, struct page *page, unsigned long addr);
1172 :
1173 : vm_fault_t finish_fault(struct vm_fault *vmf);
1174 : vm_fault_t finish_mkwrite_fault(struct vm_fault *vmf);
1175 : #endif
1176 :
1177 : /*
1178 : * Multiple processes may "see" the same page. E.g. for untouched
1179 : * mappings of /dev/null, all processes see the same page full of
1180 : * zeroes, and text pages of executables and shared libraries have
1181 : * only one copy in memory, at most, normally.
1182 : *
1183 : * For the non-reserved pages, page_count(page) denotes a reference count.
1184 : * page_count() == 0 means the page is free. page->lru is then used for
1185 : * freelist management in the buddy allocator.
1186 : * page_count() > 0 means the page has been allocated.
1187 : *
1188 : * Pages are allocated by the slab allocator in order to provide memory
1189 : * to kmalloc and kmem_cache_alloc. In this case, the management of the
1190 : * page, and the fields in 'struct page' are the responsibility of mm/slab.c
1191 : * unless a particular usage is carefully commented. (the responsibility of
1192 : * freeing the kmalloc memory is the caller's, of course).
1193 : *
1194 : * A page may be used by anyone else who does a __get_free_page().
1195 : * In this case, page_count still tracks the references, and should only
1196 : * be used through the normal accessor functions. The top bits of page->flags
1197 : * and page->virtual store page management information, but all other fields
1198 : * are unused and could be used privately, carefully. The management of this
1199 : * page is the responsibility of the one who allocated it, and those who have
1200 : * subsequently been given references to it.
1201 : *
1202 : * The other pages (we may call them "pagecache pages") are completely
1203 : * managed by the Linux memory manager: I/O, buffers, swapping etc.
1204 : * The following discussion applies only to them.
1205 : *
1206 : * A pagecache page contains an opaque `private' member, which belongs to the
1207 : * page's address_space. Usually, this is the address of a circular list of
1208 : * the page's disk buffers. PG_private must be set to tell the VM to call
1209 : * into the filesystem to release these pages.
1210 : *
1211 : * A page may belong to an inode's memory mapping. In this case, page->mapping
1212 : * is the pointer to the inode, and page->index is the file offset of the page,
1213 : * in units of PAGE_SIZE.
1214 : *
1215 : * If pagecache pages are not associated with an inode, they are said to be
1216 : * anonymous pages. These may become associated with the swapcache, and in that
1217 : * case PG_swapcache is set, and page->private is an offset into the swapcache.
1218 : *
1219 : * In either case (swapcache or inode backed), the pagecache itself holds one
1220 : * reference to the page. Setting PG_private should also increment the
1221 : * refcount. The each user mapping also has a reference to the page.
1222 : *
1223 : * The pagecache pages are stored in a per-mapping radix tree, which is
1224 : * rooted at mapping->i_pages, and indexed by offset.
1225 : * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
1226 : * lists, we instead now tag pages as dirty/writeback in the radix tree.
1227 : *
1228 : * All pagecache pages may be subject to I/O:
1229 : * - inode pages may need to be read from disk,
1230 : * - inode pages which have been modified and are MAP_SHARED may need
1231 : * to be written back to the inode on disk,
1232 : * - anonymous pages (including MAP_PRIVATE file mappings) which have been
1233 : * modified may need to be swapped out to swap space and (later) to be read
1234 : * back into memory.
1235 : */
1236 :
1237 : #if defined(CONFIG_ZONE_DEVICE) && defined(CONFIG_FS_DAX)
1238 : DECLARE_STATIC_KEY_FALSE(devmap_managed_key);
1239 :
1240 : bool __put_devmap_managed_page_refs(struct page *page, int refs);
1241 : static inline bool put_devmap_managed_page_refs(struct page *page, int refs)
1242 : {
1243 : if (!static_branch_unlikely(&devmap_managed_key))
1244 : return false;
1245 : if (!is_zone_device_page(page))
1246 : return false;
1247 : return __put_devmap_managed_page_refs(page, refs);
1248 : }
1249 : #else /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
1250 : static inline bool put_devmap_managed_page_refs(struct page *page, int refs)
1251 : {
1252 : return false;
1253 : }
1254 : #endif /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
1255 :
1256 : static inline bool put_devmap_managed_page(struct page *page)
1257 : {
1258 0 : return put_devmap_managed_page_refs(page, 1);
1259 : }
1260 :
1261 : /* 127: arbitrary random number, small enough to assemble well */
1262 : #define folio_ref_zero_or_close_to_overflow(folio) \
1263 : ((unsigned int) folio_ref_count(folio) + 127u <= 127u)
1264 :
1265 : /**
1266 : * folio_get - Increment the reference count on a folio.
1267 : * @folio: The folio.
1268 : *
1269 : * Context: May be called in any context, as long as you know that
1270 : * you have a refcount on the folio. If you do not already have one,
1271 : * folio_try_get() may be the right interface for you to use.
1272 : */
1273 : static inline void folio_get(struct folio *folio)
1274 : {
1275 : VM_BUG_ON_FOLIO(folio_ref_zero_or_close_to_overflow(folio), folio);
1276 0 : folio_ref_inc(folio);
1277 : }
1278 :
1279 : static inline void get_page(struct page *page)
1280 : {
1281 0 : folio_get(page_folio(page));
1282 : }
1283 :
1284 0 : static inline __must_check bool try_get_page(struct page *page)
1285 : {
1286 0 : page = compound_head(page);
1287 0 : if (WARN_ON_ONCE(page_ref_count(page) <= 0))
1288 : return false;
1289 0 : page_ref_inc(page);
1290 0 : return true;
1291 : }
1292 :
1293 : /**
1294 : * folio_put - Decrement the reference count on a folio.
1295 : * @folio: The folio.
1296 : *
1297 : * If the folio's reference count reaches zero, the memory will be
1298 : * released back to the page allocator and may be used by another
1299 : * allocation immediately. Do not access the memory or the struct folio
1300 : * after calling folio_put() unless you can be sure that it wasn't the
1301 : * last reference.
1302 : *
1303 : * Context: May be called in process or interrupt context, but not in NMI
1304 : * context. May be called while holding a spinlock.
1305 : */
1306 : static inline void folio_put(struct folio *folio)
1307 : {
1308 0 : if (folio_put_testzero(folio))
1309 0 : __folio_put(folio);
1310 : }
1311 :
1312 : /**
1313 : * folio_put_refs - Reduce the reference count on a folio.
1314 : * @folio: The folio.
1315 : * @refs: The amount to subtract from the folio's reference count.
1316 : *
1317 : * If the folio's reference count reaches zero, the memory will be
1318 : * released back to the page allocator and may be used by another
1319 : * allocation immediately. Do not access the memory or the struct folio
1320 : * after calling folio_put_refs() unless you can be sure that these weren't
1321 : * the last references.
1322 : *
1323 : * Context: May be called in process or interrupt context, but not in NMI
1324 : * context. May be called while holding a spinlock.
1325 : */
1326 : static inline void folio_put_refs(struct folio *folio, int refs)
1327 : {
1328 0 : if (folio_ref_sub_and_test(folio, refs))
1329 0 : __folio_put(folio);
1330 : }
1331 :
1332 : /*
1333 : * union release_pages_arg - an array of pages or folios
1334 : *
1335 : * release_pages() releases a simple array of multiple pages, and
1336 : * accepts various different forms of said page array: either
1337 : * a regular old boring array of pages, an array of folios, or
1338 : * an array of encoded page pointers.
1339 : *
1340 : * The transparent union syntax for this kind of "any of these
1341 : * argument types" is all kinds of ugly, so look away.
1342 : */
1343 : typedef union {
1344 : struct page **pages;
1345 : struct folio **folios;
1346 : struct encoded_page **encoded_pages;
1347 : } release_pages_arg __attribute__ ((__transparent_union__));
1348 :
1349 : void release_pages(release_pages_arg, int nr);
1350 :
1351 : /**
1352 : * folios_put - Decrement the reference count on an array of folios.
1353 : * @folios: The folios.
1354 : * @nr: How many folios there are.
1355 : *
1356 : * Like folio_put(), but for an array of folios. This is more efficient
1357 : * than writing the loop yourself as it will optimise the locks which
1358 : * need to be taken if the folios are freed.
1359 : *
1360 : * Context: May be called in process or interrupt context, but not in NMI
1361 : * context. May be called while holding a spinlock.
1362 : */
1363 : static inline void folios_put(struct folio **folios, unsigned int nr)
1364 : {
1365 0 : release_pages(folios, nr);
1366 : }
1367 :
1368 0 : static inline void put_page(struct page *page)
1369 : {
1370 0 : struct folio *folio = page_folio(page);
1371 :
1372 : /*
1373 : * For some devmap managed pages we need to catch refcount transition
1374 : * from 2 to 1:
1375 : */
1376 0 : if (put_devmap_managed_page(&folio->page))
1377 : return;
1378 : folio_put(folio);
1379 : }
1380 :
1381 : /*
1382 : * GUP_PIN_COUNTING_BIAS, and the associated functions that use it, overload
1383 : * the page's refcount so that two separate items are tracked: the original page
1384 : * reference count, and also a new count of how many pin_user_pages() calls were
1385 : * made against the page. ("gup-pinned" is another term for the latter).
1386 : *
1387 : * With this scheme, pin_user_pages() becomes special: such pages are marked as
1388 : * distinct from normal pages. As such, the unpin_user_page() call (and its
1389 : * variants) must be used in order to release gup-pinned pages.
1390 : *
1391 : * Choice of value:
1392 : *
1393 : * By making GUP_PIN_COUNTING_BIAS a power of two, debugging of page reference
1394 : * counts with respect to pin_user_pages() and unpin_user_page() becomes
1395 : * simpler, due to the fact that adding an even power of two to the page
1396 : * refcount has the effect of using only the upper N bits, for the code that
1397 : * counts up using the bias value. This means that the lower bits are left for
1398 : * the exclusive use of the original code that increments and decrements by one
1399 : * (or at least, by much smaller values than the bias value).
1400 : *
1401 : * Of course, once the lower bits overflow into the upper bits (and this is
1402 : * OK, because subtraction recovers the original values), then visual inspection
1403 : * no longer suffices to directly view the separate counts. However, for normal
1404 : * applications that don't have huge page reference counts, this won't be an
1405 : * issue.
1406 : *
1407 : * Locking: the lockless algorithm described in folio_try_get_rcu()
1408 : * provides safe operation for get_user_pages(), page_mkclean() and
1409 : * other calls that race to set up page table entries.
1410 : */
1411 : #define GUP_PIN_COUNTING_BIAS (1U << 10)
1412 :
1413 : void unpin_user_page(struct page *page);
1414 : void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages,
1415 : bool make_dirty);
1416 : void unpin_user_page_range_dirty_lock(struct page *page, unsigned long npages,
1417 : bool make_dirty);
1418 : void unpin_user_pages(struct page **pages, unsigned long npages);
1419 :
1420 : static inline bool is_cow_mapping(vm_flags_t flags)
1421 : {
1422 0 : return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
1423 : }
1424 :
1425 : #ifndef CONFIG_MMU
1426 : static inline bool is_nommu_shared_mapping(vm_flags_t flags)
1427 : {
1428 : /*
1429 : * NOMMU shared mappings are ordinary MAP_SHARED mappings and selected
1430 : * R/O MAP_PRIVATE file mappings that are an effective R/O overlay of
1431 : * a file mapping. R/O MAP_PRIVATE mappings might still modify
1432 : * underlying memory if ptrace is active, so this is only possible if
1433 : * ptrace does not apply. Note that there is no mprotect() to upgrade
1434 : * write permissions later.
1435 : */
1436 : return flags & (VM_MAYSHARE | VM_MAYOVERLAY);
1437 : }
1438 : #endif
1439 :
1440 : #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
1441 : #define SECTION_IN_PAGE_FLAGS
1442 : #endif
1443 :
1444 : /*
1445 : * The identification function is mainly used by the buddy allocator for
1446 : * determining if two pages could be buddies. We are not really identifying
1447 : * the zone since we could be using the section number id if we do not have
1448 : * node id available in page flags.
1449 : * We only guarantee that it will return the same value for two combinable
1450 : * pages in a zone.
1451 : */
1452 : static inline int page_zone_id(struct page *page)
1453 : {
1454 12418 : return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK;
1455 : }
1456 :
1457 : #ifdef NODE_NOT_IN_PAGE_FLAGS
1458 : extern int page_to_nid(const struct page *page);
1459 : #else
1460 : static inline int page_to_nid(const struct page *page)
1461 : {
1462 206506 : struct page *p = (struct page *)page;
1463 :
1464 : return (PF_POISONED_CHECK(p)->flags >> NODES_PGSHIFT) & NODES_MASK;
1465 : }
1466 : #endif
1467 :
1468 : static inline int folio_nid(const struct folio *folio)
1469 : {
1470 33257 : return page_to_nid(&folio->page);
1471 : }
1472 :
1473 : #ifdef CONFIG_NUMA_BALANCING
1474 : /* page access time bits needs to hold at least 4 seconds */
1475 : #define PAGE_ACCESS_TIME_MIN_BITS 12
1476 : #if LAST_CPUPID_SHIFT < PAGE_ACCESS_TIME_MIN_BITS
1477 : #define PAGE_ACCESS_TIME_BUCKETS \
1478 : (PAGE_ACCESS_TIME_MIN_BITS - LAST_CPUPID_SHIFT)
1479 : #else
1480 : #define PAGE_ACCESS_TIME_BUCKETS 0
1481 : #endif
1482 :
1483 : #define PAGE_ACCESS_TIME_MASK \
1484 : (LAST_CPUPID_MASK << PAGE_ACCESS_TIME_BUCKETS)
1485 :
1486 : static inline int cpu_pid_to_cpupid(int cpu, int pid)
1487 : {
1488 : return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK);
1489 : }
1490 :
1491 : static inline int cpupid_to_pid(int cpupid)
1492 : {
1493 : return cpupid & LAST__PID_MASK;
1494 : }
1495 :
1496 : static inline int cpupid_to_cpu(int cpupid)
1497 : {
1498 : return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK;
1499 : }
1500 :
1501 : static inline int cpupid_to_nid(int cpupid)
1502 : {
1503 : return cpu_to_node(cpupid_to_cpu(cpupid));
1504 : }
1505 :
1506 : static inline bool cpupid_pid_unset(int cpupid)
1507 : {
1508 : return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK);
1509 : }
1510 :
1511 : static inline bool cpupid_cpu_unset(int cpupid)
1512 : {
1513 : return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK);
1514 : }
1515 :
1516 : static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid)
1517 : {
1518 : return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid);
1519 : }
1520 :
1521 : #define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid)
1522 : #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
1523 : static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1524 : {
1525 : return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK);
1526 : }
1527 :
1528 : static inline int page_cpupid_last(struct page *page)
1529 : {
1530 : return page->_last_cpupid;
1531 : }
1532 : static inline void page_cpupid_reset_last(struct page *page)
1533 : {
1534 : page->_last_cpupid = -1 & LAST_CPUPID_MASK;
1535 : }
1536 : #else
1537 : static inline int page_cpupid_last(struct page *page)
1538 : {
1539 : return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
1540 : }
1541 :
1542 : extern int page_cpupid_xchg_last(struct page *page, int cpupid);
1543 :
1544 : static inline void page_cpupid_reset_last(struct page *page)
1545 : {
1546 : page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT;
1547 : }
1548 : #endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
1549 :
1550 : static inline int xchg_page_access_time(struct page *page, int time)
1551 : {
1552 : int last_time;
1553 :
1554 : last_time = page_cpupid_xchg_last(page, time >> PAGE_ACCESS_TIME_BUCKETS);
1555 : return last_time << PAGE_ACCESS_TIME_BUCKETS;
1556 : }
1557 : #else /* !CONFIG_NUMA_BALANCING */
1558 : static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1559 : {
1560 0 : return page_to_nid(page); /* XXX */
1561 : }
1562 :
1563 : static inline int xchg_page_access_time(struct page *page, int time)
1564 : {
1565 : return 0;
1566 : }
1567 :
1568 : static inline int page_cpupid_last(struct page *page)
1569 : {
1570 : return page_to_nid(page); /* XXX */
1571 : }
1572 :
1573 : static inline int cpupid_to_nid(int cpupid)
1574 : {
1575 : return -1;
1576 : }
1577 :
1578 : static inline int cpupid_to_pid(int cpupid)
1579 : {
1580 : return -1;
1581 : }
1582 :
1583 : static inline int cpupid_to_cpu(int cpupid)
1584 : {
1585 : return -1;
1586 : }
1587 :
1588 : static inline int cpu_pid_to_cpupid(int nid, int pid)
1589 : {
1590 : return -1;
1591 : }
1592 :
1593 : static inline bool cpupid_pid_unset(int cpupid)
1594 : {
1595 : return true;
1596 : }
1597 :
1598 : static inline void page_cpupid_reset_last(struct page *page)
1599 : {
1600 : }
1601 :
1602 : static inline bool cpupid_match_pid(struct task_struct *task, int cpupid)
1603 : {
1604 : return false;
1605 : }
1606 : #endif /* CONFIG_NUMA_BALANCING */
1607 :
1608 : #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
1609 :
1610 : /*
1611 : * KASAN per-page tags are stored xor'ed with 0xff. This allows to avoid
1612 : * setting tags for all pages to native kernel tag value 0xff, as the default
1613 : * value 0x00 maps to 0xff.
1614 : */
1615 :
1616 : static inline u8 page_kasan_tag(const struct page *page)
1617 : {
1618 : u8 tag = 0xff;
1619 :
1620 : if (kasan_enabled()) {
1621 : tag = (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK;
1622 : tag ^= 0xff;
1623 : }
1624 :
1625 : return tag;
1626 : }
1627 :
1628 : static inline void page_kasan_tag_set(struct page *page, u8 tag)
1629 : {
1630 : unsigned long old_flags, flags;
1631 :
1632 : if (!kasan_enabled())
1633 : return;
1634 :
1635 : tag ^= 0xff;
1636 : old_flags = READ_ONCE(page->flags);
1637 : do {
1638 : flags = old_flags;
1639 : flags &= ~(KASAN_TAG_MASK << KASAN_TAG_PGSHIFT);
1640 : flags |= (tag & KASAN_TAG_MASK) << KASAN_TAG_PGSHIFT;
1641 : } while (unlikely(!try_cmpxchg(&page->flags, &old_flags, flags)));
1642 : }
1643 :
1644 : static inline void page_kasan_tag_reset(struct page *page)
1645 : {
1646 : if (kasan_enabled())
1647 : page_kasan_tag_set(page, 0xff);
1648 : }
1649 :
1650 : #else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
1651 :
1652 : static inline u8 page_kasan_tag(const struct page *page)
1653 : {
1654 : return 0xff;
1655 : }
1656 :
1657 : static inline void page_kasan_tag_set(struct page *page, u8 tag) { }
1658 : static inline void page_kasan_tag_reset(struct page *page) { }
1659 :
1660 : #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
1661 :
1662 : static inline struct zone *page_zone(const struct page *page)
1663 : {
1664 358662 : return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
1665 : }
1666 :
1667 : static inline pg_data_t *page_pgdat(const struct page *page)
1668 : {
1669 19497 : return NODE_DATA(page_to_nid(page));
1670 : }
1671 :
1672 : static inline struct zone *folio_zone(const struct folio *folio)
1673 : {
1674 0 : return page_zone(&folio->page);
1675 : }
1676 :
1677 : static inline pg_data_t *folio_pgdat(const struct folio *folio)
1678 : {
1679 16760 : return page_pgdat(&folio->page);
1680 : }
1681 :
1682 : #ifdef SECTION_IN_PAGE_FLAGS
1683 : static inline void set_page_section(struct page *page, unsigned long section)
1684 : {
1685 : page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
1686 : page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
1687 : }
1688 :
1689 : static inline unsigned long page_to_section(const struct page *page)
1690 : {
1691 : return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
1692 : }
1693 : #endif
1694 :
1695 : /**
1696 : * folio_pfn - Return the Page Frame Number of a folio.
1697 : * @folio: The folio.
1698 : *
1699 : * A folio may contain multiple pages. The pages have consecutive
1700 : * Page Frame Numbers.
1701 : *
1702 : * Return: The Page Frame Number of the first page in the folio.
1703 : */
1704 : static inline unsigned long folio_pfn(struct folio *folio)
1705 : {
1706 0 : return page_to_pfn(&folio->page);
1707 : }
1708 :
1709 : static inline struct folio *pfn_folio(unsigned long pfn)
1710 : {
1711 : return page_folio(pfn_to_page(pfn));
1712 : }
1713 :
1714 : /**
1715 : * folio_maybe_dma_pinned - Report if a folio may be pinned for DMA.
1716 : * @folio: The folio.
1717 : *
1718 : * This function checks if a folio has been pinned via a call to
1719 : * a function in the pin_user_pages() family.
1720 : *
1721 : * For small folios, the return value is partially fuzzy: false is not fuzzy,
1722 : * because it means "definitely not pinned for DMA", but true means "probably
1723 : * pinned for DMA, but possibly a false positive due to having at least
1724 : * GUP_PIN_COUNTING_BIAS worth of normal folio references".
1725 : *
1726 : * False positives are OK, because: a) it's unlikely for a folio to
1727 : * get that many refcounts, and b) all the callers of this routine are
1728 : * expected to be able to deal gracefully with a false positive.
1729 : *
1730 : * For large folios, the result will be exactly correct. That's because
1731 : * we have more tracking data available: the _pincount field is used
1732 : * instead of the GUP_PIN_COUNTING_BIAS scheme.
1733 : *
1734 : * For more information, please see Documentation/core-api/pin_user_pages.rst.
1735 : *
1736 : * Return: True, if it is likely that the page has been "dma-pinned".
1737 : * False, if the page is definitely not dma-pinned.
1738 : */
1739 : static inline bool folio_maybe_dma_pinned(struct folio *folio)
1740 : {
1741 0 : if (folio_test_large(folio))
1742 0 : return atomic_read(&folio->_pincount) > 0;
1743 :
1744 : /*
1745 : * folio_ref_count() is signed. If that refcount overflows, then
1746 : * folio_ref_count() returns a negative value, and callers will avoid
1747 : * further incrementing the refcount.
1748 : *
1749 : * Here, for that overflow case, use the sign bit to count a little
1750 : * bit higher via unsigned math, and thus still get an accurate result.
1751 : */
1752 0 : return ((unsigned int)folio_ref_count(folio)) >=
1753 : GUP_PIN_COUNTING_BIAS;
1754 : }
1755 :
1756 : static inline bool page_maybe_dma_pinned(struct page *page)
1757 : {
1758 0 : return folio_maybe_dma_pinned(page_folio(page));
1759 : }
1760 :
1761 : /*
1762 : * This should most likely only be called during fork() to see whether we
1763 : * should break the cow immediately for an anon page on the src mm.
1764 : *
1765 : * The caller has to hold the PT lock and the vma->vm_mm->->write_protect_seq.
1766 : */
1767 0 : static inline bool page_needs_cow_for_dma(struct vm_area_struct *vma,
1768 : struct page *page)
1769 : {
1770 : VM_BUG_ON(!(raw_read_seqcount(&vma->vm_mm->write_protect_seq) & 1));
1771 :
1772 0 : if (!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))
1773 : return false;
1774 :
1775 : return page_maybe_dma_pinned(page);
1776 : }
1777 :
1778 : /* MIGRATE_CMA and ZONE_MOVABLE do not allow pin pages */
1779 : #ifdef CONFIG_MIGRATION
1780 : static inline bool is_longterm_pinnable_page(struct page *page)
1781 : {
1782 : #ifdef CONFIG_CMA
1783 : int mt = get_pageblock_migratetype(page);
1784 :
1785 : if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE)
1786 : return false;
1787 : #endif
1788 : /* The zero page may always be pinned */
1789 0 : if (is_zero_pfn(page_to_pfn(page)))
1790 : return true;
1791 :
1792 : /* Coherent device memory must always allow eviction. */
1793 0 : if (is_device_coherent_page(page))
1794 : return false;
1795 :
1796 : /* Otherwise, non-movable zone pages can be pinned. */
1797 0 : return !is_zone_movable_page(page);
1798 : }
1799 : #else
1800 : static inline bool is_longterm_pinnable_page(struct page *page)
1801 : {
1802 : return true;
1803 : }
1804 : #endif
1805 :
1806 : static inline bool folio_is_longterm_pinnable(struct folio *folio)
1807 : {
1808 0 : return is_longterm_pinnable_page(&folio->page);
1809 : }
1810 :
1811 : static inline void set_page_zone(struct page *page, enum zone_type zone)
1812 : {
1813 : page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
1814 262670 : page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
1815 : }
1816 :
1817 : static inline void set_page_node(struct page *page, unsigned long node)
1818 : {
1819 : page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
1820 : page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
1821 : }
1822 :
1823 : static inline void set_page_links(struct page *page, enum zone_type zone,
1824 : unsigned long node, unsigned long pfn)
1825 : {
1826 525340 : set_page_zone(page, zone);
1827 262670 : set_page_node(page, node);
1828 : #ifdef SECTION_IN_PAGE_FLAGS
1829 : set_page_section(page, pfn_to_section_nr(pfn));
1830 : #endif
1831 : }
1832 :
1833 : /**
1834 : * folio_nr_pages - The number of pages in the folio.
1835 : * @folio: The folio.
1836 : *
1837 : * Return: A positive power of two.
1838 : */
1839 : static inline long folio_nr_pages(struct folio *folio)
1840 : {
1841 0 : if (!folio_test_large(folio))
1842 : return 1;
1843 : #ifdef CONFIG_64BIT
1844 0 : return folio->_folio_nr_pages;
1845 : #else
1846 : return 1L << folio->_folio_order;
1847 : #endif
1848 : }
1849 :
1850 : /*
1851 : * compound_nr() returns the number of pages in this potentially compound
1852 : * page. compound_nr() can be called on a tail page, and is defined to
1853 : * return 1 in that case.
1854 : */
1855 : static inline unsigned long compound_nr(struct page *page)
1856 : {
1857 0 : struct folio *folio = (struct folio *)page;
1858 :
1859 0 : if (!test_bit(PG_head, &folio->flags))
1860 : return 1;
1861 : #ifdef CONFIG_64BIT
1862 0 : return folio->_folio_nr_pages;
1863 : #else
1864 : return 1L << folio->_folio_order;
1865 : #endif
1866 : }
1867 :
1868 : /**
1869 : * thp_nr_pages - The number of regular pages in this huge page.
1870 : * @page: The head page of a huge page.
1871 : */
1872 : static inline int thp_nr_pages(struct page *page)
1873 : {
1874 0 : return folio_nr_pages((struct folio *)page);
1875 : }
1876 :
1877 : /**
1878 : * folio_next - Move to the next physical folio.
1879 : * @folio: The folio we're currently operating on.
1880 : *
1881 : * If you have physically contiguous memory which may span more than
1882 : * one folio (eg a &struct bio_vec), use this function to move from one
1883 : * folio to the next. Do not use it if the memory is only virtually
1884 : * contiguous as the folios are almost certainly not adjacent to each
1885 : * other. This is the folio equivalent to writing ``page++``.
1886 : *
1887 : * Context: We assume that the folios are refcounted and/or locked at a
1888 : * higher level and do not adjust the reference counts.
1889 : * Return: The next struct folio.
1890 : */
1891 : static inline struct folio *folio_next(struct folio *folio)
1892 : {
1893 : return (struct folio *)folio_page(folio, folio_nr_pages(folio));
1894 : }
1895 :
1896 : /**
1897 : * folio_shift - The size of the memory described by this folio.
1898 : * @folio: The folio.
1899 : *
1900 : * A folio represents a number of bytes which is a power-of-two in size.
1901 : * This function tells you which power-of-two the folio is. See also
1902 : * folio_size() and folio_order().
1903 : *
1904 : * Context: The caller should have a reference on the folio to prevent
1905 : * it from being split. It is not necessary for the folio to be locked.
1906 : * Return: The base-2 logarithm of the size of this folio.
1907 : */
1908 : static inline unsigned int folio_shift(struct folio *folio)
1909 : {
1910 0 : return PAGE_SHIFT + folio_order(folio);
1911 : }
1912 :
1913 : /**
1914 : * folio_size - The number of bytes in a folio.
1915 : * @folio: The folio.
1916 : *
1917 : * Context: The caller should have a reference on the folio to prevent
1918 : * it from being split. It is not necessary for the folio to be locked.
1919 : * Return: The number of bytes in this folio.
1920 : */
1921 : static inline size_t folio_size(struct folio *folio)
1922 : {
1923 0 : return PAGE_SIZE << folio_order(folio);
1924 : }
1925 :
1926 : /**
1927 : * folio_estimated_sharers - Estimate the number of sharers of a folio.
1928 : * @folio: The folio.
1929 : *
1930 : * folio_estimated_sharers() aims to serve as a function to efficiently
1931 : * estimate the number of processes sharing a folio. This is done by
1932 : * looking at the precise mapcount of the first subpage in the folio, and
1933 : * assuming the other subpages are the same. This may not be true for large
1934 : * folios. If you want exact mapcounts for exact calculations, look at
1935 : * page_mapcount() or folio_total_mapcount().
1936 : *
1937 : * Return: The estimated number of processes sharing a folio.
1938 : */
1939 : static inline int folio_estimated_sharers(struct folio *folio)
1940 : {
1941 : return page_mapcount(folio_page(folio, 0));
1942 : }
1943 :
1944 : #ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE
1945 : static inline int arch_make_page_accessible(struct page *page)
1946 : {
1947 : return 0;
1948 : }
1949 : #endif
1950 :
1951 : #ifndef HAVE_ARCH_MAKE_FOLIO_ACCESSIBLE
1952 : static inline int arch_make_folio_accessible(struct folio *folio)
1953 : {
1954 : int ret;
1955 0 : long i, nr = folio_nr_pages(folio);
1956 :
1957 0 : for (i = 0; i < nr; i++) {
1958 : ret = arch_make_page_accessible(folio_page(folio, i));
1959 : if (ret)
1960 : break;
1961 : }
1962 :
1963 : return ret;
1964 : }
1965 : #endif
1966 :
1967 : /*
1968 : * Some inline functions in vmstat.h depend on page_zone()
1969 : */
1970 : #include <linux/vmstat.h>
1971 :
1972 : static __always_inline void *lowmem_page_address(const struct page *page)
1973 : {
1974 93822 : return page_to_virt(page);
1975 : }
1976 :
1977 : #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
1978 : #define HASHED_PAGE_VIRTUAL
1979 : #endif
1980 :
1981 : #if defined(WANT_PAGE_VIRTUAL)
1982 : static inline void *page_address(const struct page *page)
1983 : {
1984 : return page->virtual;
1985 : }
1986 : static inline void set_page_address(struct page *page, void *address)
1987 : {
1988 : page->virtual = address;
1989 : }
1990 : #define page_address_init() do { } while(0)
1991 : #endif
1992 :
1993 : #if defined(HASHED_PAGE_VIRTUAL)
1994 : void *page_address(const struct page *page);
1995 : void set_page_address(struct page *page, void *virtual);
1996 : void page_address_init(void);
1997 : #endif
1998 :
1999 : #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
2000 : #define page_address(page) lowmem_page_address(page)
2001 : #define set_page_address(page, address) do { } while(0)
2002 : #define page_address_init() do { } while(0)
2003 : #endif
2004 :
2005 : static inline void *folio_address(const struct folio *folio)
2006 : {
2007 17200 : return page_address(&folio->page);
2008 : }
2009 :
2010 : extern void *page_rmapping(struct page *page);
2011 : extern pgoff_t __page_file_index(struct page *page);
2012 :
2013 : /*
2014 : * Return the pagecache index of the passed page. Regular pagecache pages
2015 : * use ->index whereas swapcache pages use swp_offset(->private)
2016 : */
2017 0 : static inline pgoff_t page_index(struct page *page)
2018 : {
2019 0 : if (unlikely(PageSwapCache(page)))
2020 0 : return __page_file_index(page);
2021 0 : return page->index;
2022 : }
2023 :
2024 : /*
2025 : * Return true only if the page has been allocated with
2026 : * ALLOC_NO_WATERMARKS and the low watermark was not
2027 : * met implying that the system is under some pressure.
2028 : */
2029 : static inline bool page_is_pfmemalloc(const struct page *page)
2030 : {
2031 : /*
2032 : * lru.next has bit 1 set if the page is allocated from the
2033 : * pfmemalloc reserves. Callers may simply overwrite it if
2034 : * they do not need to preserve that information.
2035 : */
2036 0 : return (uintptr_t)page->lru.next & BIT(1);
2037 : }
2038 :
2039 : /*
2040 : * Return true only if the folio has been allocated with
2041 : * ALLOC_NO_WATERMARKS and the low watermark was not
2042 : * met implying that the system is under some pressure.
2043 : */
2044 : static inline bool folio_is_pfmemalloc(const struct folio *folio)
2045 : {
2046 : /*
2047 : * lru.next has bit 1 set if the page is allocated from the
2048 : * pfmemalloc reserves. Callers may simply overwrite it if
2049 : * they do not need to preserve that information.
2050 : */
2051 8600 : return (uintptr_t)folio->lru.next & BIT(1);
2052 : }
2053 :
2054 : /*
2055 : * Only to be called by the page allocator on a freshly allocated
2056 : * page.
2057 : */
2058 : static inline void set_page_pfmemalloc(struct page *page)
2059 : {
2060 0 : page->lru.next = (void *)BIT(1);
2061 : }
2062 :
2063 : static inline void clear_page_pfmemalloc(struct page *page)
2064 : {
2065 51169 : page->lru.next = NULL;
2066 : }
2067 :
2068 : /*
2069 : * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
2070 : */
2071 : extern void pagefault_out_of_memory(void);
2072 :
2073 : #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
2074 : #define offset_in_thp(page, p) ((unsigned long)(p) & (thp_size(page) - 1))
2075 : #define offset_in_folio(folio, p) ((unsigned long)(p) & (folio_size(folio) - 1))
2076 :
2077 : /*
2078 : * Flags passed to show_mem() and show_free_areas() to suppress output in
2079 : * various contexts.
2080 : */
2081 : #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */
2082 :
2083 : extern void __show_free_areas(unsigned int flags, nodemask_t *nodemask, int max_zone_idx);
2084 : static void __maybe_unused show_free_areas(unsigned int flags, nodemask_t *nodemask)
2085 : {
2086 : __show_free_areas(flags, nodemask, MAX_NR_ZONES - 1);
2087 : }
2088 :
2089 : /*
2090 : * Parameter block passed down to zap_pte_range in exceptional cases.
2091 : */
2092 : struct zap_details {
2093 : struct folio *single_folio; /* Locked folio to be unmapped */
2094 : bool even_cows; /* Zap COWed private pages too? */
2095 : zap_flags_t zap_flags; /* Extra flags for zapping */
2096 : };
2097 :
2098 : /*
2099 : * Whether to drop the pte markers, for example, the uffd-wp information for
2100 : * file-backed memory. This should only be specified when we will completely
2101 : * drop the page in the mm, either by truncation or unmapping of the vma. By
2102 : * default, the flag is not set.
2103 : */
2104 : #define ZAP_FLAG_DROP_MARKER ((__force zap_flags_t) BIT(0))
2105 : /* Set in unmap_vmas() to indicate a final unmap call. Only used by hugetlb */
2106 : #define ZAP_FLAG_UNMAP ((__force zap_flags_t) BIT(1))
2107 :
2108 : #ifdef CONFIG_SCHED_MM_CID
2109 : void sched_mm_cid_before_execve(struct task_struct *t);
2110 : void sched_mm_cid_after_execve(struct task_struct *t);
2111 : void sched_mm_cid_fork(struct task_struct *t);
2112 : void sched_mm_cid_exit_signals(struct task_struct *t);
2113 : static inline int task_mm_cid(struct task_struct *t)
2114 : {
2115 : return t->mm_cid;
2116 : }
2117 : #else
2118 : static inline void sched_mm_cid_before_execve(struct task_struct *t) { }
2119 : static inline void sched_mm_cid_after_execve(struct task_struct *t) { }
2120 : static inline void sched_mm_cid_fork(struct task_struct *t) { }
2121 : static inline void sched_mm_cid_exit_signals(struct task_struct *t) { }
2122 : static inline int task_mm_cid(struct task_struct *t)
2123 : {
2124 : /*
2125 : * Use the processor id as a fall-back when the mm cid feature is
2126 : * disabled. This provides functional per-cpu data structure accesses
2127 : * in user-space, althrough it won't provide the memory usage benefits.
2128 : */
2129 : return raw_smp_processor_id();
2130 : }
2131 : #endif
2132 :
2133 : #ifdef CONFIG_MMU
2134 : extern bool can_do_mlock(void);
2135 : #else
2136 : static inline bool can_do_mlock(void) { return false; }
2137 : #endif
2138 : extern int user_shm_lock(size_t, struct ucounts *);
2139 : extern void user_shm_unlock(size_t, struct ucounts *);
2140 :
2141 : struct folio *vm_normal_folio(struct vm_area_struct *vma, unsigned long addr,
2142 : pte_t pte);
2143 : struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
2144 : pte_t pte);
2145 : struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
2146 : pmd_t pmd);
2147 :
2148 : void zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
2149 : unsigned long size);
2150 : void zap_page_range_single(struct vm_area_struct *vma, unsigned long address,
2151 : unsigned long size, struct zap_details *details);
2152 : static inline void zap_vma_pages(struct vm_area_struct *vma)
2153 : {
2154 : zap_page_range_single(vma, vma->vm_start,
2155 : vma->vm_end - vma->vm_start, NULL);
2156 : }
2157 : void unmap_vmas(struct mmu_gather *tlb, struct maple_tree *mt,
2158 : struct vm_area_struct *start_vma, unsigned long start,
2159 : unsigned long end, bool mm_wr_locked);
2160 :
2161 : struct mmu_notifier_range;
2162 :
2163 : void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
2164 : unsigned long end, unsigned long floor, unsigned long ceiling);
2165 : int
2166 : copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma);
2167 : int follow_pte(struct mm_struct *mm, unsigned long address,
2168 : pte_t **ptepp, spinlock_t **ptlp);
2169 : int follow_pfn(struct vm_area_struct *vma, unsigned long address,
2170 : unsigned long *pfn);
2171 : int follow_phys(struct vm_area_struct *vma, unsigned long address,
2172 : unsigned int flags, unsigned long *prot, resource_size_t *phys);
2173 : int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
2174 : void *buf, int len, int write);
2175 :
2176 : extern void truncate_pagecache(struct inode *inode, loff_t new);
2177 : extern void truncate_setsize(struct inode *inode, loff_t newsize);
2178 : void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
2179 : void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
2180 : int generic_error_remove_page(struct address_space *mapping, struct page *page);
2181 :
2182 : #ifdef CONFIG_MMU
2183 : extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
2184 : unsigned long address, unsigned int flags,
2185 : struct pt_regs *regs);
2186 : extern int fixup_user_fault(struct mm_struct *mm,
2187 : unsigned long address, unsigned int fault_flags,
2188 : bool *unlocked);
2189 : void unmap_mapping_pages(struct address_space *mapping,
2190 : pgoff_t start, pgoff_t nr, bool even_cows);
2191 : void unmap_mapping_range(struct address_space *mapping,
2192 : loff_t const holebegin, loff_t const holelen, int even_cows);
2193 : #else
2194 : static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
2195 : unsigned long address, unsigned int flags,
2196 : struct pt_regs *regs)
2197 : {
2198 : /* should never happen if there's no MMU */
2199 : BUG();
2200 : return VM_FAULT_SIGBUS;
2201 : }
2202 : static inline int fixup_user_fault(struct mm_struct *mm, unsigned long address,
2203 : unsigned int fault_flags, bool *unlocked)
2204 : {
2205 : /* should never happen if there's no MMU */
2206 : BUG();
2207 : return -EFAULT;
2208 : }
2209 : static inline void unmap_mapping_pages(struct address_space *mapping,
2210 : pgoff_t start, pgoff_t nr, bool even_cows) { }
2211 : static inline void unmap_mapping_range(struct address_space *mapping,
2212 : loff_t const holebegin, loff_t const holelen, int even_cows) { }
2213 : #endif
2214 :
2215 : static inline void unmap_shared_mapping_range(struct address_space *mapping,
2216 : loff_t const holebegin, loff_t const holelen)
2217 : {
2218 : unmap_mapping_range(mapping, holebegin, holelen, 0);
2219 : }
2220 :
2221 : extern int access_process_vm(struct task_struct *tsk, unsigned long addr,
2222 : void *buf, int len, unsigned int gup_flags);
2223 : extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
2224 : void *buf, int len, unsigned int gup_flags);
2225 : extern int __access_remote_vm(struct mm_struct *mm, unsigned long addr,
2226 : void *buf, int len, unsigned int gup_flags);
2227 :
2228 : long get_user_pages_remote(struct mm_struct *mm,
2229 : unsigned long start, unsigned long nr_pages,
2230 : unsigned int gup_flags, struct page **pages,
2231 : struct vm_area_struct **vmas, int *locked);
2232 : long pin_user_pages_remote(struct mm_struct *mm,
2233 : unsigned long start, unsigned long nr_pages,
2234 : unsigned int gup_flags, struct page **pages,
2235 : struct vm_area_struct **vmas, int *locked);
2236 : long get_user_pages(unsigned long start, unsigned long nr_pages,
2237 : unsigned int gup_flags, struct page **pages,
2238 : struct vm_area_struct **vmas);
2239 : long pin_user_pages(unsigned long start, unsigned long nr_pages,
2240 : unsigned int gup_flags, struct page **pages,
2241 : struct vm_area_struct **vmas);
2242 : long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
2243 : struct page **pages, unsigned int gup_flags);
2244 : long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
2245 : struct page **pages, unsigned int gup_flags);
2246 :
2247 : int get_user_pages_fast(unsigned long start, int nr_pages,
2248 : unsigned int gup_flags, struct page **pages);
2249 : int pin_user_pages_fast(unsigned long start, int nr_pages,
2250 : unsigned int gup_flags, struct page **pages);
2251 :
2252 : int account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc);
2253 : int __account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc,
2254 : struct task_struct *task, bool bypass_rlim);
2255 :
2256 : struct kvec;
2257 : struct page *get_dump_page(unsigned long addr);
2258 :
2259 : bool folio_mark_dirty(struct folio *folio);
2260 : bool set_page_dirty(struct page *page);
2261 : int set_page_dirty_lock(struct page *page);
2262 :
2263 : int get_cmdline(struct task_struct *task, char *buffer, int buflen);
2264 :
2265 : extern unsigned long move_page_tables(struct vm_area_struct *vma,
2266 : unsigned long old_addr, struct vm_area_struct *new_vma,
2267 : unsigned long new_addr, unsigned long len,
2268 : bool need_rmap_locks);
2269 :
2270 : /*
2271 : * Flags used by change_protection(). For now we make it a bitmap so
2272 : * that we can pass in multiple flags just like parameters. However
2273 : * for now all the callers are only use one of the flags at the same
2274 : * time.
2275 : */
2276 : /*
2277 : * Whether we should manually check if we can map individual PTEs writable,
2278 : * because something (e.g., COW, uffd-wp) blocks that from happening for all
2279 : * PTEs automatically in a writable mapping.
2280 : */
2281 : #define MM_CP_TRY_CHANGE_WRITABLE (1UL << 0)
2282 : /* Whether this protection change is for NUMA hints */
2283 : #define MM_CP_PROT_NUMA (1UL << 1)
2284 : /* Whether this change is for write protecting */
2285 : #define MM_CP_UFFD_WP (1UL << 2) /* do wp */
2286 : #define MM_CP_UFFD_WP_RESOLVE (1UL << 3) /* Resolve wp */
2287 : #define MM_CP_UFFD_WP_ALL (MM_CP_UFFD_WP | \
2288 : MM_CP_UFFD_WP_RESOLVE)
2289 :
2290 : int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot);
2291 0 : static inline bool vma_wants_manual_pte_write_upgrade(struct vm_area_struct *vma)
2292 : {
2293 : /*
2294 : * We want to check manually if we can change individual PTEs writable
2295 : * if we can't do that automatically for all PTEs in a mapping. For
2296 : * private mappings, that's always the case when we have write
2297 : * permissions as we properly have to handle COW.
2298 : */
2299 0 : if (vma->vm_flags & VM_SHARED)
2300 0 : return vma_wants_writenotify(vma, vma->vm_page_prot);
2301 0 : return !!(vma->vm_flags & VM_WRITE);
2302 :
2303 : }
2304 : bool can_change_pte_writable(struct vm_area_struct *vma, unsigned long addr,
2305 : pte_t pte);
2306 : extern long change_protection(struct mmu_gather *tlb,
2307 : struct vm_area_struct *vma, unsigned long start,
2308 : unsigned long end, unsigned long cp_flags);
2309 : extern int mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb,
2310 : struct vm_area_struct *vma, struct vm_area_struct **pprev,
2311 : unsigned long start, unsigned long end, unsigned long newflags);
2312 :
2313 : /*
2314 : * doesn't attempt to fault and will return short.
2315 : */
2316 : int get_user_pages_fast_only(unsigned long start, int nr_pages,
2317 : unsigned int gup_flags, struct page **pages);
2318 :
2319 : static inline bool get_user_page_fast_only(unsigned long addr,
2320 : unsigned int gup_flags, struct page **pagep)
2321 : {
2322 : return get_user_pages_fast_only(addr, 1, gup_flags, pagep) == 1;
2323 : }
2324 : /*
2325 : * per-process(per-mm_struct) statistics.
2326 : */
2327 : static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
2328 : {
2329 0 : return percpu_counter_read_positive(&mm->rss_stat[member]);
2330 : }
2331 :
2332 : void mm_trace_rss_stat(struct mm_struct *mm, int member);
2333 :
2334 0 : static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
2335 : {
2336 0 : percpu_counter_add(&mm->rss_stat[member], value);
2337 :
2338 0 : mm_trace_rss_stat(mm, member);
2339 0 : }
2340 :
2341 : static inline void inc_mm_counter(struct mm_struct *mm, int member)
2342 : {
2343 0 : percpu_counter_inc(&mm->rss_stat[member]);
2344 :
2345 0 : mm_trace_rss_stat(mm, member);
2346 : }
2347 :
2348 : static inline void dec_mm_counter(struct mm_struct *mm, int member)
2349 : {
2350 0 : percpu_counter_dec(&mm->rss_stat[member]);
2351 :
2352 0 : mm_trace_rss_stat(mm, member);
2353 : }
2354 :
2355 : /* Optimized variant when page is already known not to be PageAnon */
2356 : static inline int mm_counter_file(struct page *page)
2357 : {
2358 0 : if (PageSwapBacked(page))
2359 : return MM_SHMEMPAGES;
2360 : return MM_FILEPAGES;
2361 : }
2362 :
2363 0 : static inline int mm_counter(struct page *page)
2364 : {
2365 0 : if (PageAnon(page))
2366 : return MM_ANONPAGES;
2367 : return mm_counter_file(page);
2368 : }
2369 :
2370 : static inline unsigned long get_mm_rss(struct mm_struct *mm)
2371 : {
2372 0 : return get_mm_counter(mm, MM_FILEPAGES) +
2373 0 : get_mm_counter(mm, MM_ANONPAGES) +
2374 0 : get_mm_counter(mm, MM_SHMEMPAGES);
2375 : }
2376 :
2377 : static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
2378 : {
2379 0 : return max(mm->hiwater_rss, get_mm_rss(mm));
2380 : }
2381 :
2382 : static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
2383 : {
2384 : return max(mm->hiwater_vm, mm->total_vm);
2385 : }
2386 :
2387 : static inline void update_hiwater_rss(struct mm_struct *mm)
2388 : {
2389 0 : unsigned long _rss = get_mm_rss(mm);
2390 :
2391 0 : if ((mm)->hiwater_rss < _rss)
2392 0 : (mm)->hiwater_rss = _rss;
2393 : }
2394 :
2395 : static inline void update_hiwater_vm(struct mm_struct *mm)
2396 : {
2397 0 : if (mm->hiwater_vm < mm->total_vm)
2398 0 : mm->hiwater_vm = mm->total_vm;
2399 : }
2400 :
2401 : static inline void reset_mm_hiwater_rss(struct mm_struct *mm)
2402 : {
2403 0 : mm->hiwater_rss = get_mm_rss(mm);
2404 : }
2405 :
2406 : static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
2407 : struct mm_struct *mm)
2408 : {
2409 0 : unsigned long hiwater_rss = get_mm_hiwater_rss(mm);
2410 :
2411 0 : if (*maxrss < hiwater_rss)
2412 0 : *maxrss = hiwater_rss;
2413 : }
2414 :
2415 : #if defined(SPLIT_RSS_COUNTING)
2416 : void sync_mm_rss(struct mm_struct *mm);
2417 : #else
2418 : static inline void sync_mm_rss(struct mm_struct *mm)
2419 : {
2420 : }
2421 : #endif
2422 :
2423 : #ifndef CONFIG_ARCH_HAS_PTE_SPECIAL
2424 : static inline int pte_special(pte_t pte)
2425 : {
2426 : return 0;
2427 : }
2428 :
2429 : static inline pte_t pte_mkspecial(pte_t pte)
2430 : {
2431 : return pte;
2432 : }
2433 : #endif
2434 :
2435 : #ifndef CONFIG_ARCH_HAS_PTE_DEVMAP
2436 : static inline int pte_devmap(pte_t pte)
2437 : {
2438 : return 0;
2439 : }
2440 : #endif
2441 :
2442 : extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
2443 : spinlock_t **ptl);
2444 : static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
2445 : spinlock_t **ptl)
2446 : {
2447 : pte_t *ptep;
2448 0 : __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl));
2449 : return ptep;
2450 : }
2451 :
2452 : #ifdef __PAGETABLE_P4D_FOLDED
2453 : static inline int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
2454 : unsigned long address)
2455 : {
2456 : return 0;
2457 : }
2458 : #else
2459 : int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
2460 : #endif
2461 :
2462 : #if defined(__PAGETABLE_PUD_FOLDED) || !defined(CONFIG_MMU)
2463 : static inline int __pud_alloc(struct mm_struct *mm, p4d_t *p4d,
2464 : unsigned long address)
2465 : {
2466 : return 0;
2467 : }
2468 : static inline void mm_inc_nr_puds(struct mm_struct *mm) {}
2469 : static inline void mm_dec_nr_puds(struct mm_struct *mm) {}
2470 :
2471 : #else
2472 : int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address);
2473 :
2474 : static inline void mm_inc_nr_puds(struct mm_struct *mm)
2475 : {
2476 : if (mm_pud_folded(mm))
2477 : return;
2478 : atomic_long_add(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
2479 : }
2480 :
2481 : static inline void mm_dec_nr_puds(struct mm_struct *mm)
2482 : {
2483 : if (mm_pud_folded(mm))
2484 : return;
2485 : atomic_long_sub(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
2486 : }
2487 : #endif
2488 :
2489 : #if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU)
2490 : static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
2491 : unsigned long address)
2492 : {
2493 : return 0;
2494 : }
2495 :
2496 : static inline void mm_inc_nr_pmds(struct mm_struct *mm) {}
2497 : static inline void mm_dec_nr_pmds(struct mm_struct *mm) {}
2498 :
2499 : #else
2500 : int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
2501 :
2502 : static inline void mm_inc_nr_pmds(struct mm_struct *mm)
2503 : {
2504 : if (mm_pmd_folded(mm))
2505 : return;
2506 2 : atomic_long_add(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2507 : }
2508 :
2509 : static inline void mm_dec_nr_pmds(struct mm_struct *mm)
2510 : {
2511 : if (mm_pmd_folded(mm))
2512 : return;
2513 0 : atomic_long_sub(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2514 : }
2515 : #endif
2516 :
2517 : #ifdef CONFIG_MMU
2518 : static inline void mm_pgtables_bytes_init(struct mm_struct *mm)
2519 : {
2520 0 : atomic_long_set(&mm->pgtables_bytes, 0);
2521 : }
2522 :
2523 : static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2524 : {
2525 0 : return atomic_long_read(&mm->pgtables_bytes);
2526 : }
2527 :
2528 : static inline void mm_inc_nr_ptes(struct mm_struct *mm)
2529 : {
2530 0 : atomic_long_add(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2531 : }
2532 :
2533 : static inline void mm_dec_nr_ptes(struct mm_struct *mm)
2534 : {
2535 0 : atomic_long_sub(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2536 : }
2537 : #else
2538 :
2539 : static inline void mm_pgtables_bytes_init(struct mm_struct *mm) {}
2540 : static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2541 : {
2542 : return 0;
2543 : }
2544 :
2545 : static inline void mm_inc_nr_ptes(struct mm_struct *mm) {}
2546 : static inline void mm_dec_nr_ptes(struct mm_struct *mm) {}
2547 : #endif
2548 :
2549 : int __pte_alloc(struct mm_struct *mm, pmd_t *pmd);
2550 : int __pte_alloc_kernel(pmd_t *pmd);
2551 :
2552 : #if defined(CONFIG_MMU)
2553 :
2554 : static inline p4d_t *p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
2555 : unsigned long address)
2556 : {
2557 0 : return (unlikely(pgd_none(*pgd)) && __p4d_alloc(mm, pgd, address)) ?
2558 0 : NULL : p4d_offset(pgd, address);
2559 : }
2560 :
2561 : static inline pud_t *pud_alloc(struct mm_struct *mm, p4d_t *p4d,
2562 : unsigned long address)
2563 : {
2564 0 : return (unlikely(p4d_none(*p4d)) && __pud_alloc(mm, p4d, address)) ?
2565 0 : NULL : pud_offset(p4d, address);
2566 : }
2567 :
2568 0 : static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
2569 : {
2570 0 : return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
2571 0 : NULL: pmd_offset(pud, address);
2572 : }
2573 : #endif /* CONFIG_MMU */
2574 :
2575 : #if USE_SPLIT_PTE_PTLOCKS
2576 : #if ALLOC_SPLIT_PTLOCKS
2577 : void __init ptlock_cache_init(void);
2578 : extern bool ptlock_alloc(struct page *page);
2579 : extern void ptlock_free(struct page *page);
2580 :
2581 : static inline spinlock_t *ptlock_ptr(struct page *page)
2582 : {
2583 : return page->ptl;
2584 : }
2585 : #else /* ALLOC_SPLIT_PTLOCKS */
2586 : static inline void ptlock_cache_init(void)
2587 : {
2588 : }
2589 :
2590 : static inline bool ptlock_alloc(struct page *page)
2591 : {
2592 : return true;
2593 : }
2594 :
2595 : static inline void ptlock_free(struct page *page)
2596 : {
2597 : }
2598 :
2599 : static inline spinlock_t *ptlock_ptr(struct page *page)
2600 : {
2601 : return &page->ptl;
2602 : }
2603 : #endif /* ALLOC_SPLIT_PTLOCKS */
2604 :
2605 : static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2606 : {
2607 : return ptlock_ptr(pmd_page(*pmd));
2608 : }
2609 :
2610 : static inline bool ptlock_init(struct page *page)
2611 : {
2612 : /*
2613 : * prep_new_page() initialize page->private (and therefore page->ptl)
2614 : * with 0. Make sure nobody took it in use in between.
2615 : *
2616 : * It can happen if arch try to use slab for page table allocation:
2617 : * slab code uses page->slab_cache, which share storage with page->ptl.
2618 : */
2619 : VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page);
2620 : if (!ptlock_alloc(page))
2621 : return false;
2622 : spin_lock_init(ptlock_ptr(page));
2623 : return true;
2624 : }
2625 :
2626 : #else /* !USE_SPLIT_PTE_PTLOCKS */
2627 : /*
2628 : * We use mm->page_table_lock to guard all pagetable pages of the mm.
2629 : */
2630 : static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2631 : {
2632 0 : return &mm->page_table_lock;
2633 : }
2634 : static inline void ptlock_cache_init(void) {}
2635 : static inline bool ptlock_init(struct page *page) { return true; }
2636 : static inline void ptlock_free(struct page *page) {}
2637 : #endif /* USE_SPLIT_PTE_PTLOCKS */
2638 :
2639 : static inline void pgtable_init(void)
2640 : {
2641 : ptlock_cache_init();
2642 1 : pgtable_cache_init();
2643 : }
2644 :
2645 : static inline bool pgtable_pte_page_ctor(struct page *page)
2646 : {
2647 0 : if (!ptlock_init(page))
2648 : return false;
2649 0 : __SetPageTable(page);
2650 0 : inc_lruvec_page_state(page, NR_PAGETABLE);
2651 : return true;
2652 : }
2653 :
2654 : static inline void pgtable_pte_page_dtor(struct page *page)
2655 : {
2656 0 : ptlock_free(page);
2657 0 : __ClearPageTable(page);
2658 0 : dec_lruvec_page_state(page, NR_PAGETABLE);
2659 : }
2660 :
2661 : #define pte_offset_map_lock(mm, pmd, address, ptlp) \
2662 : ({ \
2663 : spinlock_t *__ptl = pte_lockptr(mm, pmd); \
2664 : pte_t *__pte = pte_offset_map(pmd, address); \
2665 : *(ptlp) = __ptl; \
2666 : spin_lock(__ptl); \
2667 : __pte; \
2668 : })
2669 :
2670 : #define pte_unmap_unlock(pte, ptl) do { \
2671 : spin_unlock(ptl); \
2672 : pte_unmap(pte); \
2673 : } while (0)
2674 :
2675 : #define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd))
2676 :
2677 : #define pte_alloc_map(mm, pmd, address) \
2678 : (pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address))
2679 :
2680 : #define pte_alloc_map_lock(mm, pmd, address, ptlp) \
2681 : (pte_alloc(mm, pmd) ? \
2682 : NULL : pte_offset_map_lock(mm, pmd, address, ptlp))
2683 :
2684 : #define pte_alloc_kernel(pmd, address) \
2685 : ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \
2686 : NULL: pte_offset_kernel(pmd, address))
2687 :
2688 : #if USE_SPLIT_PMD_PTLOCKS
2689 :
2690 : static inline struct page *pmd_pgtable_page(pmd_t *pmd)
2691 : {
2692 : unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
2693 : return virt_to_page((void *)((unsigned long) pmd & mask));
2694 : }
2695 :
2696 : static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
2697 : {
2698 : return ptlock_ptr(pmd_pgtable_page(pmd));
2699 : }
2700 :
2701 : static inline bool pmd_ptlock_init(struct page *page)
2702 : {
2703 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2704 : page->pmd_huge_pte = NULL;
2705 : #endif
2706 : return ptlock_init(page);
2707 : }
2708 :
2709 : static inline void pmd_ptlock_free(struct page *page)
2710 : {
2711 : #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2712 : VM_BUG_ON_PAGE(page->pmd_huge_pte, page);
2713 : #endif
2714 : ptlock_free(page);
2715 : }
2716 :
2717 : #define pmd_huge_pte(mm, pmd) (pmd_pgtable_page(pmd)->pmd_huge_pte)
2718 :
2719 : #else
2720 :
2721 : static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
2722 : {
2723 : return &mm->page_table_lock;
2724 : }
2725 :
2726 : static inline bool pmd_ptlock_init(struct page *page) { return true; }
2727 : static inline void pmd_ptlock_free(struct page *page) {}
2728 :
2729 : #define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte)
2730 :
2731 : #endif
2732 :
2733 : static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd)
2734 : {
2735 0 : spinlock_t *ptl = pmd_lockptr(mm, pmd);
2736 0 : spin_lock(ptl);
2737 : return ptl;
2738 : }
2739 :
2740 : static inline bool pgtable_pmd_page_ctor(struct page *page)
2741 : {
2742 1 : if (!pmd_ptlock_init(page))
2743 : return false;
2744 1 : __SetPageTable(page);
2745 2 : inc_lruvec_page_state(page, NR_PAGETABLE);
2746 : return true;
2747 : }
2748 :
2749 : static inline void pgtable_pmd_page_dtor(struct page *page)
2750 : {
2751 0 : pmd_ptlock_free(page);
2752 0 : __ClearPageTable(page);
2753 0 : dec_lruvec_page_state(page, NR_PAGETABLE);
2754 : }
2755 :
2756 : /*
2757 : * No scalability reason to split PUD locks yet, but follow the same pattern
2758 : * as the PMD locks to make it easier if we decide to. The VM should not be
2759 : * considered ready to switch to split PUD locks yet; there may be places
2760 : * which need to be converted from page_table_lock.
2761 : */
2762 : static inline spinlock_t *pud_lockptr(struct mm_struct *mm, pud_t *pud)
2763 : {
2764 : return &mm->page_table_lock;
2765 : }
2766 :
2767 : static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud)
2768 : {
2769 1 : spinlock_t *ptl = pud_lockptr(mm, pud);
2770 :
2771 1 : spin_lock(ptl);
2772 : return ptl;
2773 : }
2774 :
2775 : extern void __init pagecache_init(void);
2776 : extern void free_initmem(void);
2777 :
2778 : /*
2779 : * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
2780 : * into the buddy system. The freed pages will be poisoned with pattern
2781 : * "poison" if it's within range [0, UCHAR_MAX].
2782 : * Return pages freed into the buddy system.
2783 : */
2784 : extern unsigned long free_reserved_area(void *start, void *end,
2785 : int poison, const char *s);
2786 :
2787 : extern void adjust_managed_page_count(struct page *page, long count);
2788 : extern void mem_init_print_info(void);
2789 :
2790 : extern void reserve_bootmem_region(phys_addr_t start, phys_addr_t end);
2791 :
2792 : /* Free the reserved page into the buddy system, so it gets managed. */
2793 : static inline void free_reserved_page(struct page *page)
2794 : {
2795 0 : ClearPageReserved(page);
2796 0 : init_page_count(page);
2797 0 : __free_page(page);
2798 0 : adjust_managed_page_count(page, 1);
2799 : }
2800 : #define free_highmem_page(page) free_reserved_page(page)
2801 :
2802 : static inline void mark_page_reserved(struct page *page)
2803 : {
2804 : SetPageReserved(page);
2805 : adjust_managed_page_count(page, -1);
2806 : }
2807 :
2808 : /*
2809 : * Default method to free all the __init memory into the buddy system.
2810 : * The freed pages will be poisoned with pattern "poison" if it's within
2811 : * range [0, UCHAR_MAX].
2812 : * Return pages freed into the buddy system.
2813 : */
2814 : static inline unsigned long free_initmem_default(int poison)
2815 : {
2816 : extern char __init_begin[], __init_end[];
2817 :
2818 0 : return free_reserved_area(&__init_begin, &__init_end,
2819 : poison, "unused kernel image (initmem)");
2820 : }
2821 :
2822 : static inline unsigned long get_num_physpages(void)
2823 : {
2824 : int nid;
2825 1 : unsigned long phys_pages = 0;
2826 :
2827 2 : for_each_online_node(nid)
2828 1 : phys_pages += node_present_pages(nid);
2829 :
2830 : return phys_pages;
2831 : }
2832 :
2833 : /*
2834 : * Using memblock node mappings, an architecture may initialise its
2835 : * zones, allocate the backing mem_map and account for memory holes in an
2836 : * architecture independent manner.
2837 : *
2838 : * An architecture is expected to register range of page frames backed by
2839 : * physical memory with memblock_add[_node]() before calling
2840 : * free_area_init() passing in the PFN each zone ends at. At a basic
2841 : * usage, an architecture is expected to do something like
2842 : *
2843 : * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
2844 : * max_highmem_pfn};
2845 : * for_each_valid_physical_page_range()
2846 : * memblock_add_node(base, size, nid, MEMBLOCK_NONE)
2847 : * free_area_init(max_zone_pfns);
2848 : */
2849 : void free_area_init(unsigned long *max_zone_pfn);
2850 : unsigned long node_map_pfn_alignment(void);
2851 : unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn,
2852 : unsigned long end_pfn);
2853 : extern unsigned long absent_pages_in_range(unsigned long start_pfn,
2854 : unsigned long end_pfn);
2855 : extern void get_pfn_range_for_nid(unsigned int nid,
2856 : unsigned long *start_pfn, unsigned long *end_pfn);
2857 :
2858 : #ifndef CONFIG_NUMA
2859 : static inline int early_pfn_to_nid(unsigned long pfn)
2860 : {
2861 : return 0;
2862 : }
2863 : #else
2864 : /* please see mm/page_alloc.c */
2865 : extern int __meminit early_pfn_to_nid(unsigned long pfn);
2866 : #endif
2867 :
2868 : extern void set_dma_reserve(unsigned long new_dma_reserve);
2869 : extern void memmap_init_range(unsigned long, int, unsigned long,
2870 : unsigned long, unsigned long, enum meminit_context,
2871 : struct vmem_altmap *, int migratetype);
2872 : extern void setup_per_zone_wmarks(void);
2873 : extern void calculate_min_free_kbytes(void);
2874 : extern int __meminit init_per_zone_wmark_min(void);
2875 : extern void mem_init(void);
2876 : extern void __init mmap_init(void);
2877 :
2878 : extern void __show_mem(unsigned int flags, nodemask_t *nodemask, int max_zone_idx);
2879 : static inline void show_mem(unsigned int flags, nodemask_t *nodemask)
2880 : {
2881 0 : __show_mem(flags, nodemask, MAX_NR_ZONES - 1);
2882 : }
2883 : extern long si_mem_available(void);
2884 : extern void si_meminfo(struct sysinfo * val);
2885 : extern void si_meminfo_node(struct sysinfo *val, int nid);
2886 : #ifdef __HAVE_ARCH_RESERVED_KERNEL_PAGES
2887 : extern unsigned long arch_reserved_kernel_pages(void);
2888 : #endif
2889 :
2890 : extern __printf(3, 4)
2891 : void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...);
2892 :
2893 : extern void setup_per_cpu_pageset(void);
2894 :
2895 : /* page_alloc.c */
2896 : extern int min_free_kbytes;
2897 : extern int watermark_boost_factor;
2898 : extern int watermark_scale_factor;
2899 : extern bool arch_has_descending_max_zone_pfns(void);
2900 :
2901 : /* nommu.c */
2902 : extern atomic_long_t mmap_pages_allocated;
2903 : extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
2904 :
2905 : /* interval_tree.c */
2906 : void vma_interval_tree_insert(struct vm_area_struct *node,
2907 : struct rb_root_cached *root);
2908 : void vma_interval_tree_insert_after(struct vm_area_struct *node,
2909 : struct vm_area_struct *prev,
2910 : struct rb_root_cached *root);
2911 : void vma_interval_tree_remove(struct vm_area_struct *node,
2912 : struct rb_root_cached *root);
2913 : struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root_cached *root,
2914 : unsigned long start, unsigned long last);
2915 : struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
2916 : unsigned long start, unsigned long last);
2917 :
2918 : #define vma_interval_tree_foreach(vma, root, start, last) \
2919 : for (vma = vma_interval_tree_iter_first(root, start, last); \
2920 : vma; vma = vma_interval_tree_iter_next(vma, start, last))
2921 :
2922 : void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
2923 : struct rb_root_cached *root);
2924 : void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
2925 : struct rb_root_cached *root);
2926 : struct anon_vma_chain *
2927 : anon_vma_interval_tree_iter_first(struct rb_root_cached *root,
2928 : unsigned long start, unsigned long last);
2929 : struct anon_vma_chain *anon_vma_interval_tree_iter_next(
2930 : struct anon_vma_chain *node, unsigned long start, unsigned long last);
2931 : #ifdef CONFIG_DEBUG_VM_RB
2932 : void anon_vma_interval_tree_verify(struct anon_vma_chain *node);
2933 : #endif
2934 :
2935 : #define anon_vma_interval_tree_foreach(avc, root, start, last) \
2936 : for (avc = anon_vma_interval_tree_iter_first(root, start, last); \
2937 : avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))
2938 :
2939 : /* mmap.c */
2940 : extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin);
2941 : extern int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma,
2942 : unsigned long start, unsigned long end, pgoff_t pgoff,
2943 : struct vm_area_struct *next);
2944 : extern int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma,
2945 : unsigned long start, unsigned long end, pgoff_t pgoff);
2946 : extern struct vm_area_struct *vma_merge(struct vma_iterator *vmi,
2947 : struct mm_struct *, struct vm_area_struct *prev, unsigned long addr,
2948 : unsigned long end, unsigned long vm_flags, struct anon_vma *,
2949 : struct file *, pgoff_t, struct mempolicy *, struct vm_userfaultfd_ctx,
2950 : struct anon_vma_name *);
2951 : extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
2952 : extern int __split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
2953 : unsigned long addr, int new_below);
2954 : extern int split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
2955 : unsigned long addr, int new_below);
2956 : extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
2957 : extern void unlink_file_vma(struct vm_area_struct *);
2958 : extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
2959 : unsigned long addr, unsigned long len, pgoff_t pgoff,
2960 : bool *need_rmap_locks);
2961 : extern void exit_mmap(struct mm_struct *);
2962 :
2963 : static inline int check_data_rlimit(unsigned long rlim,
2964 : unsigned long new,
2965 : unsigned long start,
2966 : unsigned long end_data,
2967 : unsigned long start_data)
2968 : {
2969 0 : if (rlim < RLIM_INFINITY) {
2970 0 : if (((new - start) + (end_data - start_data)) > rlim)
2971 : return -ENOSPC;
2972 : }
2973 :
2974 : return 0;
2975 : }
2976 :
2977 : extern int mm_take_all_locks(struct mm_struct *mm);
2978 : extern void mm_drop_all_locks(struct mm_struct *mm);
2979 :
2980 : extern int set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
2981 : extern int replace_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
2982 : extern struct file *get_mm_exe_file(struct mm_struct *mm);
2983 : extern struct file *get_task_exe_file(struct task_struct *task);
2984 :
2985 : extern bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long npages);
2986 : extern void vm_stat_account(struct mm_struct *, vm_flags_t, long npages);
2987 :
2988 : extern bool vma_is_special_mapping(const struct vm_area_struct *vma,
2989 : const struct vm_special_mapping *sm);
2990 : extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm,
2991 : unsigned long addr, unsigned long len,
2992 : unsigned long flags,
2993 : const struct vm_special_mapping *spec);
2994 : /* This is an obsolete alternative to _install_special_mapping. */
2995 : extern int install_special_mapping(struct mm_struct *mm,
2996 : unsigned long addr, unsigned long len,
2997 : unsigned long flags, struct page **pages);
2998 :
2999 : unsigned long randomize_stack_top(unsigned long stack_top);
3000 : unsigned long randomize_page(unsigned long start, unsigned long range);
3001 :
3002 : extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
3003 :
3004 : extern unsigned long mmap_region(struct file *file, unsigned long addr,
3005 : unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
3006 : struct list_head *uf);
3007 : extern unsigned long do_mmap(struct file *file, unsigned long addr,
3008 : unsigned long len, unsigned long prot, unsigned long flags,
3009 : unsigned long pgoff, unsigned long *populate, struct list_head *uf);
3010 : extern int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm,
3011 : unsigned long start, size_t len, struct list_head *uf,
3012 : bool downgrade);
3013 : extern int do_munmap(struct mm_struct *, unsigned long, size_t,
3014 : struct list_head *uf);
3015 : extern int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior);
3016 :
3017 : #ifdef CONFIG_MMU
3018 : extern int do_vma_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma,
3019 : unsigned long start, unsigned long end,
3020 : struct list_head *uf, bool downgrade);
3021 : extern int __mm_populate(unsigned long addr, unsigned long len,
3022 : int ignore_errors);
3023 : static inline void mm_populate(unsigned long addr, unsigned long len)
3024 : {
3025 : /* Ignore errors */
3026 0 : (void) __mm_populate(addr, len, 1);
3027 : }
3028 : #else
3029 : static inline void mm_populate(unsigned long addr, unsigned long len) {}
3030 : #endif
3031 :
3032 : /* These take the mm semaphore themselves */
3033 : extern int __must_check vm_brk(unsigned long, unsigned long);
3034 : extern int __must_check vm_brk_flags(unsigned long, unsigned long, unsigned long);
3035 : extern int vm_munmap(unsigned long, size_t);
3036 : extern unsigned long __must_check vm_mmap(struct file *, unsigned long,
3037 : unsigned long, unsigned long,
3038 : unsigned long, unsigned long);
3039 :
3040 : struct vm_unmapped_area_info {
3041 : #define VM_UNMAPPED_AREA_TOPDOWN 1
3042 : unsigned long flags;
3043 : unsigned long length;
3044 : unsigned long low_limit;
3045 : unsigned long high_limit;
3046 : unsigned long align_mask;
3047 : unsigned long align_offset;
3048 : };
3049 :
3050 : extern unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info);
3051 :
3052 : /* truncate.c */
3053 : extern void truncate_inode_pages(struct address_space *, loff_t);
3054 : extern void truncate_inode_pages_range(struct address_space *,
3055 : loff_t lstart, loff_t lend);
3056 : extern void truncate_inode_pages_final(struct address_space *);
3057 :
3058 : /* generic vm_area_ops exported for stackable file systems */
3059 : extern vm_fault_t filemap_fault(struct vm_fault *vmf);
3060 : extern vm_fault_t filemap_map_pages(struct vm_fault *vmf,
3061 : pgoff_t start_pgoff, pgoff_t end_pgoff);
3062 : extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf);
3063 :
3064 : extern unsigned long stack_guard_gap;
3065 : /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
3066 : extern int expand_stack(struct vm_area_struct *vma, unsigned long address);
3067 :
3068 : /* CONFIG_STACK_GROWSUP still needs to grow downwards at some places */
3069 : extern int expand_downwards(struct vm_area_struct *vma,
3070 : unsigned long address);
3071 : #if VM_GROWSUP
3072 : extern int expand_upwards(struct vm_area_struct *vma, unsigned long address);
3073 : #else
3074 : #define expand_upwards(vma, address) (0)
3075 : #endif
3076 :
3077 : /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */
3078 : extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
3079 : extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
3080 : struct vm_area_struct **pprev);
3081 :
3082 : /*
3083 : * Look up the first VMA which intersects the interval [start_addr, end_addr)
3084 : * NULL if none. Assume start_addr < end_addr.
3085 : */
3086 : struct vm_area_struct *find_vma_intersection(struct mm_struct *mm,
3087 : unsigned long start_addr, unsigned long end_addr);
3088 :
3089 : /**
3090 : * vma_lookup() - Find a VMA at a specific address
3091 : * @mm: The process address space.
3092 : * @addr: The user address.
3093 : *
3094 : * Return: The vm_area_struct at the given address, %NULL otherwise.
3095 : */
3096 : static inline
3097 : struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr)
3098 : {
3099 0 : return mtree_load(&mm->mm_mt, addr);
3100 : }
3101 :
3102 : static inline unsigned long vm_start_gap(struct vm_area_struct *vma)
3103 : {
3104 0 : unsigned long vm_start = vma->vm_start;
3105 :
3106 0 : if (vma->vm_flags & VM_GROWSDOWN) {
3107 0 : vm_start -= stack_guard_gap;
3108 0 : if (vm_start > vma->vm_start)
3109 0 : vm_start = 0;
3110 : }
3111 : return vm_start;
3112 : }
3113 :
3114 : static inline unsigned long vm_end_gap(struct vm_area_struct *vma)
3115 : {
3116 0 : unsigned long vm_end = vma->vm_end;
3117 :
3118 : if (vma->vm_flags & VM_GROWSUP) {
3119 : vm_end += stack_guard_gap;
3120 : if (vm_end < vma->vm_end)
3121 : vm_end = -PAGE_SIZE;
3122 : }
3123 : return vm_end;
3124 : }
3125 :
3126 : static inline unsigned long vma_pages(struct vm_area_struct *vma)
3127 : {
3128 0 : return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
3129 : }
3130 :
3131 : /* Look up the first VMA which exactly match the interval vm_start ... vm_end */
3132 : static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
3133 : unsigned long vm_start, unsigned long vm_end)
3134 : {
3135 0 : struct vm_area_struct *vma = vma_lookup(mm, vm_start);
3136 :
3137 0 : if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
3138 0 : vma = NULL;
3139 :
3140 : return vma;
3141 : }
3142 :
3143 : static inline bool range_in_vma(struct vm_area_struct *vma,
3144 : unsigned long start, unsigned long end)
3145 : {
3146 0 : return (vma && vma->vm_start <= start && end <= vma->vm_end);
3147 : }
3148 :
3149 : #ifdef CONFIG_MMU
3150 : pgprot_t vm_get_page_prot(unsigned long vm_flags);
3151 : void vma_set_page_prot(struct vm_area_struct *vma);
3152 : #else
3153 : static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
3154 : {
3155 : return __pgprot(0);
3156 : }
3157 : static inline void vma_set_page_prot(struct vm_area_struct *vma)
3158 : {
3159 : vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
3160 : }
3161 : #endif
3162 :
3163 : void vma_set_file(struct vm_area_struct *vma, struct file *file);
3164 :
3165 : #ifdef CONFIG_NUMA_BALANCING
3166 : unsigned long change_prot_numa(struct vm_area_struct *vma,
3167 : unsigned long start, unsigned long end);
3168 : #endif
3169 :
3170 : struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr);
3171 : int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
3172 : unsigned long pfn, unsigned long size, pgprot_t);
3173 : int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr,
3174 : unsigned long pfn, unsigned long size, pgprot_t prot);
3175 : int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
3176 : int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr,
3177 : struct page **pages, unsigned long *num);
3178 : int vm_map_pages(struct vm_area_struct *vma, struct page **pages,
3179 : unsigned long num);
3180 : int vm_map_pages_zero(struct vm_area_struct *vma, struct page **pages,
3181 : unsigned long num);
3182 : vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
3183 : unsigned long pfn);
3184 : vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
3185 : unsigned long pfn, pgprot_t pgprot);
3186 : vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
3187 : pfn_t pfn);
3188 : vm_fault_t vmf_insert_mixed_prot(struct vm_area_struct *vma, unsigned long addr,
3189 : pfn_t pfn, pgprot_t pgprot);
3190 : vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
3191 : unsigned long addr, pfn_t pfn);
3192 : int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
3193 :
3194 : static inline vm_fault_t vmf_insert_page(struct vm_area_struct *vma,
3195 : unsigned long addr, struct page *page)
3196 : {
3197 : int err = vm_insert_page(vma, addr, page);
3198 :
3199 : if (err == -ENOMEM)
3200 : return VM_FAULT_OOM;
3201 : if (err < 0 && err != -EBUSY)
3202 : return VM_FAULT_SIGBUS;
3203 :
3204 : return VM_FAULT_NOPAGE;
3205 : }
3206 :
3207 : #ifndef io_remap_pfn_range
3208 : static inline int io_remap_pfn_range(struct vm_area_struct *vma,
3209 : unsigned long addr, unsigned long pfn,
3210 : unsigned long size, pgprot_t prot)
3211 : {
3212 0 : return remap_pfn_range(vma, addr, pfn, size, pgprot_decrypted(prot));
3213 : }
3214 : #endif
3215 :
3216 : static inline vm_fault_t vmf_error(int err)
3217 : {
3218 0 : if (err == -ENOMEM)
3219 : return VM_FAULT_OOM;
3220 : return VM_FAULT_SIGBUS;
3221 : }
3222 :
3223 : struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
3224 : unsigned int foll_flags);
3225 :
3226 : static inline int vm_fault_to_errno(vm_fault_t vm_fault, int foll_flags)
3227 : {
3228 0 : if (vm_fault & VM_FAULT_OOM)
3229 : return -ENOMEM;
3230 0 : if (vm_fault & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE))
3231 0 : return (foll_flags & FOLL_HWPOISON) ? -EHWPOISON : -EFAULT;
3232 0 : if (vm_fault & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV))
3233 : return -EFAULT;
3234 : return 0;
3235 : }
3236 :
3237 : /*
3238 : * Indicates whether GUP can follow a PROT_NONE mapped page, or whether
3239 : * a (NUMA hinting) fault is required.
3240 : */
3241 : static inline bool gup_can_follow_protnone(unsigned int flags)
3242 : {
3243 : /*
3244 : * FOLL_FORCE has to be able to make progress even if the VMA is
3245 : * inaccessible. Further, FOLL_FORCE access usually does not represent
3246 : * application behaviour and we should avoid triggering NUMA hinting
3247 : * faults.
3248 : */
3249 : return flags & FOLL_FORCE;
3250 : }
3251 :
3252 : typedef int (*pte_fn_t)(pte_t *pte, unsigned long addr, void *data);
3253 : extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
3254 : unsigned long size, pte_fn_t fn, void *data);
3255 : extern int apply_to_existing_page_range(struct mm_struct *mm,
3256 : unsigned long address, unsigned long size,
3257 : pte_fn_t fn, void *data);
3258 :
3259 : extern void __init init_mem_debugging_and_hardening(void);
3260 : #ifdef CONFIG_PAGE_POISONING
3261 : extern void __kernel_poison_pages(struct page *page, int numpages);
3262 : extern void __kernel_unpoison_pages(struct page *page, int numpages);
3263 : extern bool _page_poisoning_enabled_early;
3264 : DECLARE_STATIC_KEY_FALSE(_page_poisoning_enabled);
3265 : static inline bool page_poisoning_enabled(void)
3266 : {
3267 : return _page_poisoning_enabled_early;
3268 : }
3269 : /*
3270 : * For use in fast paths after init_mem_debugging() has run, or when a
3271 : * false negative result is not harmful when called too early.
3272 : */
3273 : static inline bool page_poisoning_enabled_static(void)
3274 : {
3275 : return static_branch_unlikely(&_page_poisoning_enabled);
3276 : }
3277 : static inline void kernel_poison_pages(struct page *page, int numpages)
3278 : {
3279 : if (page_poisoning_enabled_static())
3280 : __kernel_poison_pages(page, numpages);
3281 : }
3282 : static inline void kernel_unpoison_pages(struct page *page, int numpages)
3283 : {
3284 : if (page_poisoning_enabled_static())
3285 : __kernel_unpoison_pages(page, numpages);
3286 : }
3287 : #else
3288 : static inline bool page_poisoning_enabled(void) { return false; }
3289 : static inline bool page_poisoning_enabled_static(void) { return false; }
3290 : static inline void __kernel_poison_pages(struct page *page, int nunmpages) { }
3291 : static inline void kernel_poison_pages(struct page *page, int numpages) { }
3292 : static inline void kernel_unpoison_pages(struct page *page, int numpages) { }
3293 : #endif
3294 :
3295 : DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
3296 : static inline bool want_init_on_alloc(gfp_t flags)
3297 : {
3298 51444 : if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
3299 : &init_on_alloc))
3300 : return true;
3301 51169 : return flags & __GFP_ZERO;
3302 : }
3303 :
3304 : DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free);
3305 50643 : static inline bool want_init_on_free(void)
3306 : {
3307 102346 : return static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
3308 : &init_on_free);
3309 : }
3310 :
3311 : extern bool _debug_pagealloc_enabled_early;
3312 : DECLARE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
3313 :
3314 : static inline bool debug_pagealloc_enabled(void)
3315 : {
3316 : return IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) &&
3317 : _debug_pagealloc_enabled_early;
3318 : }
3319 :
3320 : /*
3321 : * For use in fast paths after init_debug_pagealloc() has run, or when a
3322 : * false negative result is not harmful when called too early.
3323 : */
3324 : static inline bool debug_pagealloc_enabled_static(void)
3325 : {
3326 : if (!IS_ENABLED(CONFIG_DEBUG_PAGEALLOC))
3327 : return false;
3328 :
3329 : return static_branch_unlikely(&_debug_pagealloc_enabled);
3330 : }
3331 :
3332 : #ifdef CONFIG_DEBUG_PAGEALLOC
3333 : /*
3334 : * To support DEBUG_PAGEALLOC architecture must ensure that
3335 : * __kernel_map_pages() never fails
3336 : */
3337 : extern void __kernel_map_pages(struct page *page, int numpages, int enable);
3338 :
3339 : static inline void debug_pagealloc_map_pages(struct page *page, int numpages)
3340 : {
3341 : if (debug_pagealloc_enabled_static())
3342 : __kernel_map_pages(page, numpages, 1);
3343 : }
3344 :
3345 : static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages)
3346 : {
3347 : if (debug_pagealloc_enabled_static())
3348 : __kernel_map_pages(page, numpages, 0);
3349 : }
3350 : #else /* CONFIG_DEBUG_PAGEALLOC */
3351 : static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {}
3352 : static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {}
3353 : #endif /* CONFIG_DEBUG_PAGEALLOC */
3354 :
3355 : #ifdef __HAVE_ARCH_GATE_AREA
3356 : extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
3357 : extern int in_gate_area_no_mm(unsigned long addr);
3358 : extern int in_gate_area(struct mm_struct *mm, unsigned long addr);
3359 : #else
3360 : static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
3361 : {
3362 : return NULL;
3363 : }
3364 : static inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
3365 : static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
3366 : {
3367 : return 0;
3368 : }
3369 : #endif /* __HAVE_ARCH_GATE_AREA */
3370 :
3371 : extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm);
3372 :
3373 : #ifdef CONFIG_SYSCTL
3374 : extern int sysctl_drop_caches;
3375 : int drop_caches_sysctl_handler(struct ctl_table *, int, void *, size_t *,
3376 : loff_t *);
3377 : #endif
3378 :
3379 : void drop_slab(void);
3380 :
3381 : #ifndef CONFIG_MMU
3382 : #define randomize_va_space 0
3383 : #else
3384 : extern int randomize_va_space;
3385 : #endif
3386 :
3387 : const char * arch_vma_name(struct vm_area_struct *vma);
3388 : #ifdef CONFIG_MMU
3389 : void print_vma_addr(char *prefix, unsigned long rip);
3390 : #else
3391 : static inline void print_vma_addr(char *prefix, unsigned long rip)
3392 : {
3393 : }
3394 : #endif
3395 :
3396 : void *sparse_buffer_alloc(unsigned long size);
3397 : struct page * __populate_section_memmap(unsigned long pfn,
3398 : unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
3399 : struct dev_pagemap *pgmap);
3400 : void pmd_init(void *addr);
3401 : void pud_init(void *addr);
3402 : pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
3403 : p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node);
3404 : pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node);
3405 : pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
3406 : pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
3407 : struct vmem_altmap *altmap, struct page *reuse);
3408 : void *vmemmap_alloc_block(unsigned long size, int node);
3409 : struct vmem_altmap;
3410 : void *vmemmap_alloc_block_buf(unsigned long size, int node,
3411 : struct vmem_altmap *altmap);
3412 : void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
3413 : void vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
3414 : unsigned long addr, unsigned long next);
3415 : int vmemmap_check_pmd(pmd_t *pmd, int node,
3416 : unsigned long addr, unsigned long next);
3417 : int vmemmap_populate_basepages(unsigned long start, unsigned long end,
3418 : int node, struct vmem_altmap *altmap);
3419 : int vmemmap_populate_hugepages(unsigned long start, unsigned long end,
3420 : int node, struct vmem_altmap *altmap);
3421 : int vmemmap_populate(unsigned long start, unsigned long end, int node,
3422 : struct vmem_altmap *altmap);
3423 : void vmemmap_populate_print_last(void);
3424 : #ifdef CONFIG_MEMORY_HOTPLUG
3425 : void vmemmap_free(unsigned long start, unsigned long end,
3426 : struct vmem_altmap *altmap);
3427 : #endif
3428 : void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
3429 : unsigned long nr_pages);
3430 :
3431 : enum mf_flags {
3432 : MF_COUNT_INCREASED = 1 << 0,
3433 : MF_ACTION_REQUIRED = 1 << 1,
3434 : MF_MUST_KILL = 1 << 2,
3435 : MF_SOFT_OFFLINE = 1 << 3,
3436 : MF_UNPOISON = 1 << 4,
3437 : MF_SW_SIMULATED = 1 << 5,
3438 : MF_NO_RETRY = 1 << 6,
3439 : };
3440 : int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index,
3441 : unsigned long count, int mf_flags);
3442 : extern int memory_failure(unsigned long pfn, int flags);
3443 : extern void memory_failure_queue_kick(int cpu);
3444 : extern int unpoison_memory(unsigned long pfn);
3445 : extern int sysctl_memory_failure_early_kill;
3446 : extern int sysctl_memory_failure_recovery;
3447 : extern void shake_page(struct page *p);
3448 : extern atomic_long_t num_poisoned_pages __read_mostly;
3449 : extern int soft_offline_page(unsigned long pfn, int flags);
3450 : #ifdef CONFIG_MEMORY_FAILURE
3451 : extern void memory_failure_queue(unsigned long pfn, int flags);
3452 : extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
3453 : bool *migratable_cleared);
3454 : void num_poisoned_pages_inc(unsigned long pfn);
3455 : void num_poisoned_pages_sub(unsigned long pfn, long i);
3456 : #else
3457 : static inline void memory_failure_queue(unsigned long pfn, int flags)
3458 : {
3459 : }
3460 :
3461 : static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
3462 : bool *migratable_cleared)
3463 : {
3464 : return 0;
3465 : }
3466 :
3467 : static inline void num_poisoned_pages_inc(unsigned long pfn)
3468 : {
3469 : }
3470 :
3471 : static inline void num_poisoned_pages_sub(unsigned long pfn, long i)
3472 : {
3473 : }
3474 : #endif
3475 :
3476 : #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG)
3477 : extern void memblk_nr_poison_inc(unsigned long pfn);
3478 : extern void memblk_nr_poison_sub(unsigned long pfn, long i);
3479 : #else
3480 : static inline void memblk_nr_poison_inc(unsigned long pfn)
3481 : {
3482 : }
3483 :
3484 : static inline void memblk_nr_poison_sub(unsigned long pfn, long i)
3485 : {
3486 : }
3487 : #endif
3488 :
3489 : #ifndef arch_memory_failure
3490 : static inline int arch_memory_failure(unsigned long pfn, int flags)
3491 : {
3492 : return -ENXIO;
3493 : }
3494 : #endif
3495 :
3496 : #ifndef arch_is_platform_page
3497 : static inline bool arch_is_platform_page(u64 paddr)
3498 : {
3499 : return false;
3500 : }
3501 : #endif
3502 :
3503 : /*
3504 : * Error handlers for various types of pages.
3505 : */
3506 : enum mf_result {
3507 : MF_IGNORED, /* Error: cannot be handled */
3508 : MF_FAILED, /* Error: handling failed */
3509 : MF_DELAYED, /* Will be handled later */
3510 : MF_RECOVERED, /* Successfully recovered */
3511 : };
3512 :
3513 : enum mf_action_page_type {
3514 : MF_MSG_KERNEL,
3515 : MF_MSG_KERNEL_HIGH_ORDER,
3516 : MF_MSG_SLAB,
3517 : MF_MSG_DIFFERENT_COMPOUND,
3518 : MF_MSG_HUGE,
3519 : MF_MSG_FREE_HUGE,
3520 : MF_MSG_UNMAP_FAILED,
3521 : MF_MSG_DIRTY_SWAPCACHE,
3522 : MF_MSG_CLEAN_SWAPCACHE,
3523 : MF_MSG_DIRTY_MLOCKED_LRU,
3524 : MF_MSG_CLEAN_MLOCKED_LRU,
3525 : MF_MSG_DIRTY_UNEVICTABLE_LRU,
3526 : MF_MSG_CLEAN_UNEVICTABLE_LRU,
3527 : MF_MSG_DIRTY_LRU,
3528 : MF_MSG_CLEAN_LRU,
3529 : MF_MSG_TRUNCATED_LRU,
3530 : MF_MSG_BUDDY,
3531 : MF_MSG_DAX,
3532 : MF_MSG_UNSPLIT_THP,
3533 : MF_MSG_UNKNOWN,
3534 : };
3535 :
3536 : /*
3537 : * Sysfs entries for memory failure handling statistics.
3538 : */
3539 : extern const struct attribute_group memory_failure_attr_group;
3540 :
3541 : #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
3542 : extern void clear_huge_page(struct page *page,
3543 : unsigned long addr_hint,
3544 : unsigned int pages_per_huge_page);
3545 : extern void copy_user_huge_page(struct page *dst, struct page *src,
3546 : unsigned long addr_hint,
3547 : struct vm_area_struct *vma,
3548 : unsigned int pages_per_huge_page);
3549 : extern long copy_huge_page_from_user(struct page *dst_page,
3550 : const void __user *usr_src,
3551 : unsigned int pages_per_huge_page,
3552 : bool allow_pagefault);
3553 :
3554 : /**
3555 : * vma_is_special_huge - Are transhuge page-table entries considered special?
3556 : * @vma: Pointer to the struct vm_area_struct to consider
3557 : *
3558 : * Whether transhuge page-table entries are considered "special" following
3559 : * the definition in vm_normal_page().
3560 : *
3561 : * Return: true if transhuge page-table entries should be considered special,
3562 : * false otherwise.
3563 : */
3564 : static inline bool vma_is_special_huge(const struct vm_area_struct *vma)
3565 : {
3566 : return vma_is_dax(vma) || (vma->vm_file &&
3567 : (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)));
3568 : }
3569 :
3570 : #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
3571 :
3572 : #ifdef CONFIG_DEBUG_PAGEALLOC
3573 : extern unsigned int _debug_guardpage_minorder;
3574 : DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
3575 :
3576 : static inline unsigned int debug_guardpage_minorder(void)
3577 : {
3578 : return _debug_guardpage_minorder;
3579 : }
3580 :
3581 : static inline bool debug_guardpage_enabled(void)
3582 : {
3583 : return static_branch_unlikely(&_debug_guardpage_enabled);
3584 : }
3585 :
3586 : static inline bool page_is_guard(struct page *page)
3587 : {
3588 : if (!debug_guardpage_enabled())
3589 : return false;
3590 :
3591 : return PageGuard(page);
3592 : }
3593 : #else
3594 : static inline unsigned int debug_guardpage_minorder(void) { return 0; }
3595 : static inline bool debug_guardpage_enabled(void) { return false; }
3596 : static inline bool page_is_guard(struct page *page) { return false; }
3597 : #endif /* CONFIG_DEBUG_PAGEALLOC */
3598 :
3599 : #if MAX_NUMNODES > 1
3600 : void __init setup_nr_node_ids(void);
3601 : #else
3602 : static inline void setup_nr_node_ids(void) {}
3603 : #endif
3604 :
3605 : extern int memcmp_pages(struct page *page1, struct page *page2);
3606 :
3607 : static inline int pages_identical(struct page *page1, struct page *page2)
3608 : {
3609 : return !memcmp_pages(page1, page2);
3610 : }
3611 :
3612 : #ifdef CONFIG_MAPPING_DIRTY_HELPERS
3613 : unsigned long clean_record_shared_mapping_range(struct address_space *mapping,
3614 : pgoff_t first_index, pgoff_t nr,
3615 : pgoff_t bitmap_pgoff,
3616 : unsigned long *bitmap,
3617 : pgoff_t *start,
3618 : pgoff_t *end);
3619 :
3620 : unsigned long wp_shared_mapping_range(struct address_space *mapping,
3621 : pgoff_t first_index, pgoff_t nr);
3622 : #endif
3623 :
3624 : extern int sysctl_nr_trim_pages;
3625 :
3626 : #ifdef CONFIG_PRINTK
3627 : void mem_dump_obj(void *object);
3628 : #else
3629 : static inline void mem_dump_obj(void *object) {}
3630 : #endif
3631 :
3632 : /**
3633 : * seal_check_future_write - Check for F_SEAL_FUTURE_WRITE flag and handle it
3634 : * @seals: the seals to check
3635 : * @vma: the vma to operate on
3636 : *
3637 : * Check whether F_SEAL_FUTURE_WRITE is set; if so, do proper check/handling on
3638 : * the vma flags. Return 0 if check pass, or <0 for errors.
3639 : */
3640 : static inline int seal_check_future_write(int seals, struct vm_area_struct *vma)
3641 : {
3642 0 : if (seals & F_SEAL_FUTURE_WRITE) {
3643 : /*
3644 : * New PROT_WRITE and MAP_SHARED mmaps are not allowed when
3645 : * "future write" seal active.
3646 : */
3647 0 : if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE))
3648 : return -EPERM;
3649 :
3650 : /*
3651 : * Since an F_SEAL_FUTURE_WRITE sealed memfd can be mapped as
3652 : * MAP_SHARED and read-only, take care to not allow mprotect to
3653 : * revert protections on such mappings. Do this only for shared
3654 : * mappings. For private mappings, don't need to mask
3655 : * VM_MAYWRITE as we still want them to be COW-writable.
3656 : */
3657 0 : if (vma->vm_flags & VM_SHARED)
3658 0 : vm_flags_clear(vma, VM_MAYWRITE);
3659 : }
3660 :
3661 : return 0;
3662 : }
3663 :
3664 : #ifdef CONFIG_ANON_VMA_NAME
3665 : int madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
3666 : unsigned long len_in,
3667 : struct anon_vma_name *anon_name);
3668 : #else
3669 : static inline int
3670 : madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
3671 : unsigned long len_in, struct anon_vma_name *anon_name) {
3672 : return 0;
3673 : }
3674 : #endif
3675 :
3676 : #endif /* _LINUX_MM_H */
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