1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_MM_H
3 #define _LINUX_MM_H
4 
5 #include <linux/errno.h>
6 #include <linux/mmdebug.h>
7 #include <linux/gfp.h>
8 #include <linux/bug.h>
9 #include <linux/list.h>
10 #include <linux/mmzone.h>
11 #include <linux/rbtree.h>
12 #include <linux/atomic.h>
13 #include <linux/debug_locks.h>
14 #include <linux/mm_types.h>
15 #include <linux/mmap_lock.h>
16 #include <linux/range.h>
17 #include <linux/pfn.h>
18 #include <linux/percpu-refcount.h>
19 #include <linux/bit_spinlock.h>
20 #include <linux/shrinker.h>
21 #include <linux/resource.h>
22 #include <linux/page_ext.h>
23 #include <linux/err.h>
24 #include <linux/page-flags.h>
25 #include <linux/page_ref.h>
26 #include <linux/overflow.h>
27 #include <linux/sizes.h>
28 #include <linux/sched.h>
29 #include <linux/pgtable.h>
30 #include <linux/kasan.h>
31 #include <linux/memremap.h>
32 #include <linux/slab.h>
33 
34 struct mempolicy;
35 struct anon_vma;
36 struct anon_vma_chain;
37 struct user_struct;
38 struct pt_regs;
39 
40 extern int sysctl_page_lock_unfairness;
41 
42 void mm_core_init(void);
43 void init_mm_internals(void);
44 
45 #ifndef CONFIG_NUMA		/* Don't use mapnrs, do it properly */
46 extern unsigned long max_mapnr;
47 
set_max_mapnr(unsigned long limit)48 static inline void set_max_mapnr(unsigned long limit)
49 {
50 	max_mapnr = limit;
51 }
52 #else
set_max_mapnr(unsigned long limit)53 static inline void set_max_mapnr(unsigned long limit) { }
54 #endif
55 
56 extern atomic_long_t _totalram_pages;
totalram_pages(void)57 static inline unsigned long totalram_pages(void)
58 {
59 	return (unsigned long)atomic_long_read(&_totalram_pages);
60 }
61 
totalram_pages_inc(void)62 static inline void totalram_pages_inc(void)
63 {
64 	atomic_long_inc(&_totalram_pages);
65 }
66 
totalram_pages_dec(void)67 static inline void totalram_pages_dec(void)
68 {
69 	atomic_long_dec(&_totalram_pages);
70 }
71 
totalram_pages_add(long count)72 static inline void totalram_pages_add(long count)
73 {
74 	atomic_long_add(count, &_totalram_pages);
75 }
76 
77 extern void * high_memory;
78 extern int page_cluster;
79 extern const int page_cluster_max;
80 
81 #ifdef CONFIG_SYSCTL
82 extern int sysctl_legacy_va_layout;
83 #else
84 #define sysctl_legacy_va_layout 0
85 #endif
86 
87 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
88 extern const int mmap_rnd_bits_min;
89 extern const int mmap_rnd_bits_max;
90 extern int mmap_rnd_bits __read_mostly;
91 #endif
92 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
93 extern const int mmap_rnd_compat_bits_min;
94 extern const int mmap_rnd_compat_bits_max;
95 extern int mmap_rnd_compat_bits __read_mostly;
96 #endif
97 
98 #include <asm/page.h>
99 #include <asm/processor.h>
100 
101 #ifndef __pa_symbol
102 #define __pa_symbol(x)  __pa(RELOC_HIDE((unsigned long)(x), 0))
103 #endif
104 
105 #ifndef page_to_virt
106 #define page_to_virt(x)	__va(PFN_PHYS(page_to_pfn(x)))
107 #endif
108 
109 #ifndef lm_alias
110 #define lm_alias(x)	__va(__pa_symbol(x))
111 #endif
112 
113 /*
114  * To prevent common memory management code establishing
115  * a zero page mapping on a read fault.
116  * This macro should be defined within <asm/pgtable.h>.
117  * s390 does this to prevent multiplexing of hardware bits
118  * related to the physical page in case of virtualization.
119  */
120 #ifndef mm_forbids_zeropage
121 #define mm_forbids_zeropage(X)	(0)
122 #endif
123 
124 /*
125  * On some architectures it is expensive to call memset() for small sizes.
126  * If an architecture decides to implement their own version of
127  * mm_zero_struct_page they should wrap the defines below in a #ifndef and
128  * define their own version of this macro in <asm/pgtable.h>
129  */
130 #if BITS_PER_LONG == 64
131 /* This function must be updated when the size of struct page grows above 96
132  * or reduces below 56. The idea that compiler optimizes out switch()
133  * statement, and only leaves move/store instructions. Also the compiler can
134  * combine write statements if they are both assignments and can be reordered,
135  * this can result in several of the writes here being dropped.
136  */
137 #define	mm_zero_struct_page(pp) __mm_zero_struct_page(pp)
__mm_zero_struct_page(struct page * page)138 static inline void __mm_zero_struct_page(struct page *page)
139 {
140 	unsigned long *_pp = (void *)page;
141 
142 	 /* Check that struct page is either 56, 64, 72, 80, 88 or 96 bytes */
143 	BUILD_BUG_ON(sizeof(struct page) & 7);
144 	BUILD_BUG_ON(sizeof(struct page) < 56);
145 	BUILD_BUG_ON(sizeof(struct page) > 96);
146 
147 	switch (sizeof(struct page)) {
148 	case 96:
149 		_pp[11] = 0;
150 		fallthrough;
151 	case 88:
152 		_pp[10] = 0;
153 		fallthrough;
154 	case 80:
155 		_pp[9] = 0;
156 		fallthrough;
157 	case 72:
158 		_pp[8] = 0;
159 		fallthrough;
160 	case 64:
161 		_pp[7] = 0;
162 		fallthrough;
163 	case 56:
164 		_pp[6] = 0;
165 		_pp[5] = 0;
166 		_pp[4] = 0;
167 		_pp[3] = 0;
168 		_pp[2] = 0;
169 		_pp[1] = 0;
170 		_pp[0] = 0;
171 	}
172 }
173 #else
174 #define mm_zero_struct_page(pp)  ((void)memset((pp), 0, sizeof(struct page)))
175 #endif
176 
177 /*
178  * Default maximum number of active map areas, this limits the number of vmas
179  * per mm struct. Users can overwrite this number by sysctl but there is a
180  * problem.
181  *
182  * When a program's coredump is generated as ELF format, a section is created
183  * per a vma. In ELF, the number of sections is represented in unsigned short.
184  * This means the number of sections should be smaller than 65535 at coredump.
185  * Because the kernel adds some informative sections to a image of program at
186  * generating coredump, we need some margin. The number of extra sections is
187  * 1-3 now and depends on arch. We use "5" as safe margin, here.
188  *
189  * ELF extended numbering allows more than 65535 sections, so 16-bit bound is
190  * not a hard limit any more. Although some userspace tools can be surprised by
191  * that.
192  */
193 #define MAPCOUNT_ELF_CORE_MARGIN	(5)
194 #define DEFAULT_MAX_MAP_COUNT	(USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
195 
196 extern int sysctl_max_map_count;
197 
198 extern unsigned long sysctl_user_reserve_kbytes;
199 extern unsigned long sysctl_admin_reserve_kbytes;
200 
201 extern int sysctl_overcommit_memory;
202 extern int sysctl_overcommit_ratio;
203 extern unsigned long sysctl_overcommit_kbytes;
204 
205 int overcommit_ratio_handler(struct ctl_table *, int, void *, size_t *,
206 		loff_t *);
207 int overcommit_kbytes_handler(struct ctl_table *, int, void *, size_t *,
208 		loff_t *);
209 int overcommit_policy_handler(struct ctl_table *, int, void *, size_t *,
210 		loff_t *);
211 
212 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
213 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
214 #define folio_page_idx(folio, p)	(page_to_pfn(p) - folio_pfn(folio))
215 #else
216 #define nth_page(page,n) ((page) + (n))
217 #define folio_page_idx(folio, p)	((p) - &(folio)->page)
218 #endif
219 
220 /* to align the pointer to the (next) page boundary */
221 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
222 
223 /* to align the pointer to the (prev) page boundary */
224 #define PAGE_ALIGN_DOWN(addr) ALIGN_DOWN(addr, PAGE_SIZE)
225 
226 /* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
227 #define PAGE_ALIGNED(addr)	IS_ALIGNED((unsigned long)(addr), PAGE_SIZE)
228 
229 #define lru_to_page(head) (list_entry((head)->prev, struct page, lru))
lru_to_folio(struct list_head * head)230 static inline struct folio *lru_to_folio(struct list_head *head)
231 {
232 	return list_entry((head)->prev, struct folio, lru);
233 }
234 
235 void setup_initial_init_mm(void *start_code, void *end_code,
236 			   void *end_data, void *brk);
237 
238 /*
239  * Linux kernel virtual memory manager primitives.
240  * The idea being to have a "virtual" mm in the same way
241  * we have a virtual fs - giving a cleaner interface to the
242  * mm details, and allowing different kinds of memory mappings
243  * (from shared memory to executable loading to arbitrary
244  * mmap() functions).
245  */
246 
247 struct vm_area_struct *vm_area_alloc(struct mm_struct *);
248 struct vm_area_struct *vm_area_dup(struct vm_area_struct *);
249 void vm_area_free(struct vm_area_struct *);
250 /* Use only if VMA has no other users */
251 void __vm_area_free(struct vm_area_struct *vma);
252 
253 #ifndef CONFIG_MMU
254 extern struct rb_root nommu_region_tree;
255 extern struct rw_semaphore nommu_region_sem;
256 
257 extern unsigned int kobjsize(const void *objp);
258 #endif
259 
260 /*
261  * vm_flags in vm_area_struct, see mm_types.h.
262  * When changing, update also include/trace/events/mmflags.h
263  */
264 #define VM_NONE		0x00000000
265 
266 #define VM_READ		0x00000001	/* currently active flags */
267 #define VM_WRITE	0x00000002
268 #define VM_EXEC		0x00000004
269 #define VM_SHARED	0x00000008
270 
271 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */
272 #define VM_MAYREAD	0x00000010	/* limits for mprotect() etc */
273 #define VM_MAYWRITE	0x00000020
274 #define VM_MAYEXEC	0x00000040
275 #define VM_MAYSHARE	0x00000080
276 
277 #define VM_GROWSDOWN	0x00000100	/* general info on the segment */
278 #ifdef CONFIG_MMU
279 #define VM_UFFD_MISSING	0x00000200	/* missing pages tracking */
280 #else /* CONFIG_MMU */
281 #define VM_MAYOVERLAY	0x00000200	/* nommu: R/O MAP_PRIVATE mapping that might overlay a file mapping */
282 #define VM_UFFD_MISSING	0
283 #endif /* CONFIG_MMU */
284 #define VM_PFNMAP	0x00000400	/* Page-ranges managed without "struct page", just pure PFN */
285 #define VM_UFFD_WP	0x00001000	/* wrprotect pages tracking */
286 
287 #define VM_LOCKED	0x00002000
288 #define VM_IO           0x00004000	/* Memory mapped I/O or similar */
289 
290 					/* Used by sys_madvise() */
291 #define VM_SEQ_READ	0x00008000	/* App will access data sequentially */
292 #define VM_RAND_READ	0x00010000	/* App will not benefit from clustered reads */
293 
294 #define VM_DONTCOPY	0x00020000      /* Do not copy this vma on fork */
295 #define VM_DONTEXPAND	0x00040000	/* Cannot expand with mremap() */
296 #define VM_LOCKONFAULT	0x00080000	/* Lock the pages covered when they are faulted in */
297 #define VM_ACCOUNT	0x00100000	/* Is a VM accounted object */
298 #define VM_NORESERVE	0x00200000	/* should the VM suppress accounting */
299 #define VM_HUGETLB	0x00400000	/* Huge TLB Page VM */
300 #define VM_SYNC		0x00800000	/* Synchronous page faults */
301 #define VM_ARCH_1	0x01000000	/* Architecture-specific flag */
302 #define VM_WIPEONFORK	0x02000000	/* Wipe VMA contents in child. */
303 #define VM_DONTDUMP	0x04000000	/* Do not include in the core dump */
304 
305 #ifdef CONFIG_MEM_SOFT_DIRTY
306 # define VM_SOFTDIRTY	0x08000000	/* Not soft dirty clean area */
307 #else
308 # define VM_SOFTDIRTY	0
309 #endif
310 
311 #define VM_MIXEDMAP	0x10000000	/* Can contain "struct page" and pure PFN pages */
312 #define VM_HUGEPAGE	0x20000000	/* MADV_HUGEPAGE marked this vma */
313 #define VM_NOHUGEPAGE	0x40000000	/* MADV_NOHUGEPAGE marked this vma */
314 #define VM_MERGEABLE	0x80000000	/* KSM may merge identical pages */
315 
316 #ifdef CONFIG_ARCH_USES_HIGH_VMA_FLAGS
317 #define VM_HIGH_ARCH_BIT_0	32	/* bit only usable on 64-bit architectures */
318 #define VM_HIGH_ARCH_BIT_1	33	/* bit only usable on 64-bit architectures */
319 #define VM_HIGH_ARCH_BIT_2	34	/* bit only usable on 64-bit architectures */
320 #define VM_HIGH_ARCH_BIT_3	35	/* bit only usable on 64-bit architectures */
321 #define VM_HIGH_ARCH_BIT_4	36	/* bit only usable on 64-bit architectures */
322 #define VM_HIGH_ARCH_BIT_5	37	/* bit only usable on 64-bit architectures */
323 #define VM_HIGH_ARCH_0	BIT(VM_HIGH_ARCH_BIT_0)
324 #define VM_HIGH_ARCH_1	BIT(VM_HIGH_ARCH_BIT_1)
325 #define VM_HIGH_ARCH_2	BIT(VM_HIGH_ARCH_BIT_2)
326 #define VM_HIGH_ARCH_3	BIT(VM_HIGH_ARCH_BIT_3)
327 #define VM_HIGH_ARCH_4	BIT(VM_HIGH_ARCH_BIT_4)
328 #define VM_HIGH_ARCH_5	BIT(VM_HIGH_ARCH_BIT_5)
329 #endif /* CONFIG_ARCH_USES_HIGH_VMA_FLAGS */
330 
331 #ifdef CONFIG_ARCH_HAS_PKEYS
332 # define VM_PKEY_SHIFT	VM_HIGH_ARCH_BIT_0
333 # define VM_PKEY_BIT0	VM_HIGH_ARCH_0	/* A protection key is a 4-bit value */
334 # define VM_PKEY_BIT1	VM_HIGH_ARCH_1	/* on x86 and 5-bit value on ppc64   */
335 # define VM_PKEY_BIT2	VM_HIGH_ARCH_2
336 # define VM_PKEY_BIT3	VM_HIGH_ARCH_3
337 #ifdef CONFIG_PPC
338 # define VM_PKEY_BIT4  VM_HIGH_ARCH_4
339 #else
340 # define VM_PKEY_BIT4  0
341 #endif
342 #endif /* CONFIG_ARCH_HAS_PKEYS */
343 
344 #ifdef CONFIG_X86_USER_SHADOW_STACK
345 /*
346  * VM_SHADOW_STACK should not be set with VM_SHARED because of lack of
347  * support core mm.
348  *
349  * These VMAs will get a single end guard page. This helps userspace protect
350  * itself from attacks. A single page is enough for current shadow stack archs
351  * (x86). See the comments near alloc_shstk() in arch/x86/kernel/shstk.c
352  * for more details on the guard size.
353  */
354 # define VM_SHADOW_STACK	VM_HIGH_ARCH_5
355 #else
356 # define VM_SHADOW_STACK	VM_NONE
357 #endif
358 
359 #if defined(CONFIG_X86)
360 # define VM_PAT		VM_ARCH_1	/* PAT reserves whole VMA at once (x86) */
361 #elif defined(CONFIG_PPC)
362 # define VM_SAO		VM_ARCH_1	/* Strong Access Ordering (powerpc) */
363 #elif defined(CONFIG_PARISC)
364 # define VM_GROWSUP	VM_ARCH_1
365 #elif defined(CONFIG_IA64)
366 # define VM_GROWSUP	VM_ARCH_1
367 #elif defined(CONFIG_SPARC64)
368 # define VM_SPARC_ADI	VM_ARCH_1	/* Uses ADI tag for access control */
369 # define VM_ARCH_CLEAR	VM_SPARC_ADI
370 #elif defined(CONFIG_ARM64)
371 # define VM_ARM64_BTI	VM_ARCH_1	/* BTI guarded page, a.k.a. GP bit */
372 # define VM_ARCH_CLEAR	VM_ARM64_BTI
373 #elif !defined(CONFIG_MMU)
374 # define VM_MAPPED_COPY	VM_ARCH_1	/* T if mapped copy of data (nommu mmap) */
375 #endif
376 
377 #if defined(CONFIG_ARM64_MTE)
378 # define VM_MTE		VM_HIGH_ARCH_0	/* Use Tagged memory for access control */
379 # define VM_MTE_ALLOWED	VM_HIGH_ARCH_1	/* Tagged memory permitted */
380 #else
381 # define VM_MTE		VM_NONE
382 # define VM_MTE_ALLOWED	VM_NONE
383 #endif
384 
385 #ifndef VM_GROWSUP
386 # define VM_GROWSUP	VM_NONE
387 #endif
388 
389 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR
390 # define VM_UFFD_MINOR_BIT	38
391 # define VM_UFFD_MINOR		BIT(VM_UFFD_MINOR_BIT)	/* UFFD minor faults */
392 #else /* !CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
393 # define VM_UFFD_MINOR		VM_NONE
394 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
395 
396 /* Bits set in the VMA until the stack is in its final location */
397 #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ | VM_STACK_EARLY)
398 
399 #define TASK_EXEC ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0)
400 
401 /* Common data flag combinations */
402 #define VM_DATA_FLAGS_TSK_EXEC	(VM_READ | VM_WRITE | TASK_EXEC | \
403 				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
404 #define VM_DATA_FLAGS_NON_EXEC	(VM_READ | VM_WRITE | VM_MAYREAD | \
405 				 VM_MAYWRITE | VM_MAYEXEC)
406 #define VM_DATA_FLAGS_EXEC	(VM_READ | VM_WRITE | VM_EXEC | \
407 				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
408 
409 #ifndef VM_DATA_DEFAULT_FLAGS		/* arch can override this */
410 #define VM_DATA_DEFAULT_FLAGS  VM_DATA_FLAGS_EXEC
411 #endif
412 
413 #ifndef VM_STACK_DEFAULT_FLAGS		/* arch can override this */
414 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
415 #endif
416 
417 #define VM_STARTGAP_FLAGS (VM_GROWSDOWN | VM_SHADOW_STACK)
418 
419 #ifdef CONFIG_STACK_GROWSUP
420 #define VM_STACK	VM_GROWSUP
421 #define VM_STACK_EARLY	VM_GROWSDOWN
422 #else
423 #define VM_STACK	VM_GROWSDOWN
424 #define VM_STACK_EARLY	0
425 #endif
426 
427 #define VM_STACK_FLAGS	(VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT)
428 
429 /* VMA basic access permission flags */
430 #define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC)
431 
432 
433 /*
434  * Special vmas that are non-mergable, non-mlock()able.
435  */
436 #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP)
437 
438 /* This mask prevents VMA from being scanned with khugepaged */
439 #define VM_NO_KHUGEPAGED (VM_SPECIAL | VM_HUGETLB)
440 
441 /* This mask defines which mm->def_flags a process can inherit its parent */
442 #define VM_INIT_DEF_MASK	VM_NOHUGEPAGE
443 
444 /* This mask represents all the VMA flag bits used by mlock */
445 #define VM_LOCKED_MASK	(VM_LOCKED | VM_LOCKONFAULT)
446 
447 /* Arch-specific flags to clear when updating VM flags on protection change */
448 #ifndef VM_ARCH_CLEAR
449 # define VM_ARCH_CLEAR	VM_NONE
450 #endif
451 #define VM_FLAGS_CLEAR	(ARCH_VM_PKEY_FLAGS | VM_ARCH_CLEAR)
452 
453 /*
454  * mapping from the currently active vm_flags protection bits (the
455  * low four bits) to a page protection mask..
456  */
457 
458 /*
459  * The default fault flags that should be used by most of the
460  * arch-specific page fault handlers.
461  */
462 #define FAULT_FLAG_DEFAULT  (FAULT_FLAG_ALLOW_RETRY | \
463 			     FAULT_FLAG_KILLABLE | \
464 			     FAULT_FLAG_INTERRUPTIBLE)
465 
466 /**
467  * fault_flag_allow_retry_first - check ALLOW_RETRY the first time
468  * @flags: Fault flags.
469  *
470  * This is mostly used for places where we want to try to avoid taking
471  * the mmap_lock for too long a time when waiting for another condition
472  * to change, in which case we can try to be polite to release the
473  * mmap_lock in the first round to avoid potential starvation of other
474  * processes that would also want the mmap_lock.
475  *
476  * Return: true if the page fault allows retry and this is the first
477  * attempt of the fault handling; false otherwise.
478  */
fault_flag_allow_retry_first(enum fault_flag flags)479 static inline bool fault_flag_allow_retry_first(enum fault_flag flags)
480 {
481 	return (flags & FAULT_FLAG_ALLOW_RETRY) &&
482 	    (!(flags & FAULT_FLAG_TRIED));
483 }
484 
485 #define FAULT_FLAG_TRACE \
486 	{ FAULT_FLAG_WRITE,		"WRITE" }, \
487 	{ FAULT_FLAG_MKWRITE,		"MKWRITE" }, \
488 	{ FAULT_FLAG_ALLOW_RETRY,	"ALLOW_RETRY" }, \
489 	{ FAULT_FLAG_RETRY_NOWAIT,	"RETRY_NOWAIT" }, \
490 	{ FAULT_FLAG_KILLABLE,		"KILLABLE" }, \
491 	{ FAULT_FLAG_TRIED,		"TRIED" }, \
492 	{ FAULT_FLAG_USER,		"USER" }, \
493 	{ FAULT_FLAG_REMOTE,		"REMOTE" }, \
494 	{ FAULT_FLAG_INSTRUCTION,	"INSTRUCTION" }, \
495 	{ FAULT_FLAG_INTERRUPTIBLE,	"INTERRUPTIBLE" }, \
496 	{ FAULT_FLAG_VMA_LOCK,		"VMA_LOCK" }
497 
498 /*
499  * vm_fault is filled by the pagefault handler and passed to the vma's
500  * ->fault function. The vma's ->fault is responsible for returning a bitmask
501  * of VM_FAULT_xxx flags that give details about how the fault was handled.
502  *
503  * MM layer fills up gfp_mask for page allocations but fault handler might
504  * alter it if its implementation requires a different allocation context.
505  *
506  * pgoff should be used in favour of virtual_address, if possible.
507  */
508 struct vm_fault {
509 	const struct {
510 		struct vm_area_struct *vma;	/* Target VMA */
511 		gfp_t gfp_mask;			/* gfp mask to be used for allocations */
512 		pgoff_t pgoff;			/* Logical page offset based on vma */
513 		unsigned long address;		/* Faulting virtual address - masked */
514 		unsigned long real_address;	/* Faulting virtual address - unmasked */
515 	};
516 	enum fault_flag flags;		/* FAULT_FLAG_xxx flags
517 					 * XXX: should really be 'const' */
518 	pmd_t *pmd;			/* Pointer to pmd entry matching
519 					 * the 'address' */
520 	pud_t *pud;			/* Pointer to pud entry matching
521 					 * the 'address'
522 					 */
523 	union {
524 		pte_t orig_pte;		/* Value of PTE at the time of fault */
525 		pmd_t orig_pmd;		/* Value of PMD at the time of fault,
526 					 * used by PMD fault only.
527 					 */
528 	};
529 
530 	struct page *cow_page;		/* Page handler may use for COW fault */
531 	struct page *page;		/* ->fault handlers should return a
532 					 * page here, unless VM_FAULT_NOPAGE
533 					 * is set (which is also implied by
534 					 * VM_FAULT_ERROR).
535 					 */
536 	/* These three entries are valid only while holding ptl lock */
537 	pte_t *pte;			/* Pointer to pte entry matching
538 					 * the 'address'. NULL if the page
539 					 * table hasn't been allocated.
540 					 */
541 	spinlock_t *ptl;		/* Page table lock.
542 					 * Protects pte page table if 'pte'
543 					 * is not NULL, otherwise pmd.
544 					 */
545 	pgtable_t prealloc_pte;		/* Pre-allocated pte page table.
546 					 * vm_ops->map_pages() sets up a page
547 					 * table from atomic context.
548 					 * do_fault_around() pre-allocates
549 					 * page table to avoid allocation from
550 					 * atomic context.
551 					 */
552 };
553 
554 /*
555  * These are the virtual MM functions - opening of an area, closing and
556  * unmapping it (needed to keep files on disk up-to-date etc), pointer
557  * to the functions called when a no-page or a wp-page exception occurs.
558  */
559 struct vm_operations_struct {
560 	void (*open)(struct vm_area_struct * area);
561 	/**
562 	 * @close: Called when the VMA is being removed from the MM.
563 	 * Context: User context.  May sleep.  Caller holds mmap_lock.
564 	 */
565 	void (*close)(struct vm_area_struct * area);
566 	/* Called any time before splitting to check if it's allowed */
567 	int (*may_split)(struct vm_area_struct *area, unsigned long addr);
568 	int (*mremap)(struct vm_area_struct *area);
569 	/*
570 	 * Called by mprotect() to make driver-specific permission
571 	 * checks before mprotect() is finalised.   The VMA must not
572 	 * be modified.  Returns 0 if mprotect() can proceed.
573 	 */
574 	int (*mprotect)(struct vm_area_struct *vma, unsigned long start,
575 			unsigned long end, unsigned long newflags);
576 	vm_fault_t (*fault)(struct vm_fault *vmf);
577 	vm_fault_t (*huge_fault)(struct vm_fault *vmf, unsigned int order);
578 	vm_fault_t (*map_pages)(struct vm_fault *vmf,
579 			pgoff_t start_pgoff, pgoff_t end_pgoff);
580 	unsigned long (*pagesize)(struct vm_area_struct * area);
581 
582 	/* notification that a previously read-only page is about to become
583 	 * writable, if an error is returned it will cause a SIGBUS */
584 	vm_fault_t (*page_mkwrite)(struct vm_fault *vmf);
585 
586 	/* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */
587 	vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf);
588 
589 	/* called by access_process_vm when get_user_pages() fails, typically
590 	 * for use by special VMAs. See also generic_access_phys() for a generic
591 	 * implementation useful for any iomem mapping.
592 	 */
593 	int (*access)(struct vm_area_struct *vma, unsigned long addr,
594 		      void *buf, int len, int write);
595 
596 	/* Called by the /proc/PID/maps code to ask the vma whether it
597 	 * has a special name.  Returning non-NULL will also cause this
598 	 * vma to be dumped unconditionally. */
599 	const char *(*name)(struct vm_area_struct *vma);
600 
601 #ifdef CONFIG_NUMA
602 	/*
603 	 * set_policy() op must add a reference to any non-NULL @new mempolicy
604 	 * to hold the policy upon return.  Caller should pass NULL @new to
605 	 * remove a policy and fall back to surrounding context--i.e. do not
606 	 * install a MPOL_DEFAULT policy, nor the task or system default
607 	 * mempolicy.
608 	 */
609 	int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
610 
611 	/*
612 	 * get_policy() op must add reference [mpol_get()] to any policy at
613 	 * (vma,addr) marked as MPOL_SHARED.  The shared policy infrastructure
614 	 * in mm/mempolicy.c will do this automatically.
615 	 * get_policy() must NOT add a ref if the policy at (vma,addr) is not
616 	 * marked as MPOL_SHARED. vma policies are protected by the mmap_lock.
617 	 * If no [shared/vma] mempolicy exists at the addr, get_policy() op
618 	 * must return NULL--i.e., do not "fallback" to task or system default
619 	 * policy.
620 	 */
621 	struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
622 					unsigned long addr);
623 #endif
624 	/*
625 	 * Called by vm_normal_page() for special PTEs to find the
626 	 * page for @addr.  This is useful if the default behavior
627 	 * (using pte_page()) would not find the correct page.
628 	 */
629 	struct page *(*find_special_page)(struct vm_area_struct *vma,
630 					  unsigned long addr);
631 };
632 
633 #ifdef CONFIG_NUMA_BALANCING
vma_numab_state_init(struct vm_area_struct * vma)634 static inline void vma_numab_state_init(struct vm_area_struct *vma)
635 {
636 	vma->numab_state = NULL;
637 }
vma_numab_state_free(struct vm_area_struct * vma)638 static inline void vma_numab_state_free(struct vm_area_struct *vma)
639 {
640 	kfree(vma->numab_state);
641 }
642 #else
vma_numab_state_init(struct vm_area_struct * vma)643 static inline void vma_numab_state_init(struct vm_area_struct *vma) {}
vma_numab_state_free(struct vm_area_struct * vma)644 static inline void vma_numab_state_free(struct vm_area_struct *vma) {}
645 #endif /* CONFIG_NUMA_BALANCING */
646 
647 #ifdef CONFIG_PER_VMA_LOCK
648 /*
649  * Try to read-lock a vma. The function is allowed to occasionally yield false
650  * locked result to avoid performance overhead, in which case we fall back to
651  * using mmap_lock. The function should never yield false unlocked result.
652  */
vma_start_read(struct vm_area_struct * vma)653 static inline bool vma_start_read(struct vm_area_struct *vma)
654 {
655 	/*
656 	 * Check before locking. A race might cause false locked result.
657 	 * We can use READ_ONCE() for the mm_lock_seq here, and don't need
658 	 * ACQUIRE semantics, because this is just a lockless check whose result
659 	 * we don't rely on for anything - the mm_lock_seq read against which we
660 	 * need ordering is below.
661 	 */
662 	if (READ_ONCE(vma->vm_lock_seq) == READ_ONCE(vma->vm_mm->mm_lock_seq))
663 		return false;
664 
665 	if (unlikely(down_read_trylock(&vma->vm_lock->lock) == 0))
666 		return false;
667 
668 	/*
669 	 * Overflow might produce false locked result.
670 	 * False unlocked result is impossible because we modify and check
671 	 * vma->vm_lock_seq under vma->vm_lock protection and mm->mm_lock_seq
672 	 * modification invalidates all existing locks.
673 	 *
674 	 * We must use ACQUIRE semantics for the mm_lock_seq so that if we are
675 	 * racing with vma_end_write_all(), we only start reading from the VMA
676 	 * after it has been unlocked.
677 	 * This pairs with RELEASE semantics in vma_end_write_all().
678 	 */
679 	if (unlikely(vma->vm_lock_seq == smp_load_acquire(&vma->vm_mm->mm_lock_seq))) {
680 		up_read(&vma->vm_lock->lock);
681 		return false;
682 	}
683 	return true;
684 }
685 
vma_end_read(struct vm_area_struct * vma)686 static inline void vma_end_read(struct vm_area_struct *vma)
687 {
688 	rcu_read_lock(); /* keeps vma alive till the end of up_read */
689 	up_read(&vma->vm_lock->lock);
690 	rcu_read_unlock();
691 }
692 
693 /* WARNING! Can only be used if mmap_lock is expected to be write-locked */
__is_vma_write_locked(struct vm_area_struct * vma,int * mm_lock_seq)694 static bool __is_vma_write_locked(struct vm_area_struct *vma, int *mm_lock_seq)
695 {
696 	mmap_assert_write_locked(vma->vm_mm);
697 
698 	/*
699 	 * current task is holding mmap_write_lock, both vma->vm_lock_seq and
700 	 * mm->mm_lock_seq can't be concurrently modified.
701 	 */
702 	*mm_lock_seq = vma->vm_mm->mm_lock_seq;
703 	return (vma->vm_lock_seq == *mm_lock_seq);
704 }
705 
706 /*
707  * Begin writing to a VMA.
708  * Exclude concurrent readers under the per-VMA lock until the currently
709  * write-locked mmap_lock is dropped or downgraded.
710  */
vma_start_write(struct vm_area_struct * vma)711 static inline void vma_start_write(struct vm_area_struct *vma)
712 {
713 	int mm_lock_seq;
714 
715 	if (__is_vma_write_locked(vma, &mm_lock_seq))
716 		return;
717 
718 	down_write(&vma->vm_lock->lock);
719 	/*
720 	 * We should use WRITE_ONCE() here because we can have concurrent reads
721 	 * from the early lockless pessimistic check in vma_start_read().
722 	 * We don't really care about the correctness of that early check, but
723 	 * we should use WRITE_ONCE() for cleanliness and to keep KCSAN happy.
724 	 */
725 	WRITE_ONCE(vma->vm_lock_seq, mm_lock_seq);
726 	up_write(&vma->vm_lock->lock);
727 }
728 
vma_assert_write_locked(struct vm_area_struct * vma)729 static inline void vma_assert_write_locked(struct vm_area_struct *vma)
730 {
731 	int mm_lock_seq;
732 
733 	VM_BUG_ON_VMA(!__is_vma_write_locked(vma, &mm_lock_seq), vma);
734 }
735 
vma_assert_locked(struct vm_area_struct * vma)736 static inline void vma_assert_locked(struct vm_area_struct *vma)
737 {
738 	if (!rwsem_is_locked(&vma->vm_lock->lock))
739 		vma_assert_write_locked(vma);
740 }
741 
vma_mark_detached(struct vm_area_struct * vma,bool detached)742 static inline void vma_mark_detached(struct vm_area_struct *vma, bool detached)
743 {
744 	/* When detaching vma should be write-locked */
745 	if (detached)
746 		vma_assert_write_locked(vma);
747 	vma->detached = detached;
748 }
749 
release_fault_lock(struct vm_fault * vmf)750 static inline void release_fault_lock(struct vm_fault *vmf)
751 {
752 	if (vmf->flags & FAULT_FLAG_VMA_LOCK)
753 		vma_end_read(vmf->vma);
754 	else
755 		mmap_read_unlock(vmf->vma->vm_mm);
756 }
757 
assert_fault_locked(struct vm_fault * vmf)758 static inline void assert_fault_locked(struct vm_fault *vmf)
759 {
760 	if (vmf->flags & FAULT_FLAG_VMA_LOCK)
761 		vma_assert_locked(vmf->vma);
762 	else
763 		mmap_assert_locked(vmf->vma->vm_mm);
764 }
765 
766 struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm,
767 					  unsigned long address);
768 
769 #else /* CONFIG_PER_VMA_LOCK */
770 
vma_start_read(struct vm_area_struct * vma)771 static inline bool vma_start_read(struct vm_area_struct *vma)
772 		{ return false; }
vma_end_read(struct vm_area_struct * vma)773 static inline void vma_end_read(struct vm_area_struct *vma) {}
vma_start_write(struct vm_area_struct * vma)774 static inline void vma_start_write(struct vm_area_struct *vma) {}
vma_assert_write_locked(struct vm_area_struct * vma)775 static inline void vma_assert_write_locked(struct vm_area_struct *vma)
776 		{ mmap_assert_write_locked(vma->vm_mm); }
vma_mark_detached(struct vm_area_struct * vma,bool detached)777 static inline void vma_mark_detached(struct vm_area_struct *vma,
778 				     bool detached) {}
779 
lock_vma_under_rcu(struct mm_struct * mm,unsigned long address)780 static inline struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm,
781 		unsigned long address)
782 {
783 	return NULL;
784 }
785 
release_fault_lock(struct vm_fault * vmf)786 static inline void release_fault_lock(struct vm_fault *vmf)
787 {
788 	mmap_read_unlock(vmf->vma->vm_mm);
789 }
790 
assert_fault_locked(struct vm_fault * vmf)791 static inline void assert_fault_locked(struct vm_fault *vmf)
792 {
793 	mmap_assert_locked(vmf->vma->vm_mm);
794 }
795 
796 #endif /* CONFIG_PER_VMA_LOCK */
797 
798 extern const struct vm_operations_struct vma_dummy_vm_ops;
799 
800 /*
801  * WARNING: vma_init does not initialize vma->vm_lock.
802  * Use vm_area_alloc()/vm_area_free() if vma needs locking.
803  */
vma_init(struct vm_area_struct * vma,struct mm_struct * mm)804 static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm)
805 {
806 	memset(vma, 0, sizeof(*vma));
807 	vma->vm_mm = mm;
808 	vma->vm_ops = &vma_dummy_vm_ops;
809 	INIT_LIST_HEAD(&vma->anon_vma_chain);
810 	vma_mark_detached(vma, false);
811 	vma_numab_state_init(vma);
812 }
813 
814 /* Use when VMA is not part of the VMA tree and needs no locking */
vm_flags_init(struct vm_area_struct * vma,vm_flags_t flags)815 static inline void vm_flags_init(struct vm_area_struct *vma,
816 				 vm_flags_t flags)
817 {
818 	ACCESS_PRIVATE(vma, __vm_flags) = flags;
819 }
820 
821 /*
822  * Use when VMA is part of the VMA tree and modifications need coordination
823  * Note: vm_flags_reset and vm_flags_reset_once do not lock the vma and
824  * it should be locked explicitly beforehand.
825  */
vm_flags_reset(struct vm_area_struct * vma,vm_flags_t flags)826 static inline void vm_flags_reset(struct vm_area_struct *vma,
827 				  vm_flags_t flags)
828 {
829 	vma_assert_write_locked(vma);
830 	vm_flags_init(vma, flags);
831 }
832 
vm_flags_reset_once(struct vm_area_struct * vma,vm_flags_t flags)833 static inline void vm_flags_reset_once(struct vm_area_struct *vma,
834 				       vm_flags_t flags)
835 {
836 	vma_assert_write_locked(vma);
837 	WRITE_ONCE(ACCESS_PRIVATE(vma, __vm_flags), flags);
838 }
839 
vm_flags_set(struct vm_area_struct * vma,vm_flags_t flags)840 static inline void vm_flags_set(struct vm_area_struct *vma,
841 				vm_flags_t flags)
842 {
843 	vma_start_write(vma);
844 	ACCESS_PRIVATE(vma, __vm_flags) |= flags;
845 }
846 
vm_flags_clear(struct vm_area_struct * vma,vm_flags_t flags)847 static inline void vm_flags_clear(struct vm_area_struct *vma,
848 				  vm_flags_t flags)
849 {
850 	vma_start_write(vma);
851 	ACCESS_PRIVATE(vma, __vm_flags) &= ~flags;
852 }
853 
854 /*
855  * Use only if VMA is not part of the VMA tree or has no other users and
856  * therefore needs no locking.
857  */
__vm_flags_mod(struct vm_area_struct * vma,vm_flags_t set,vm_flags_t clear)858 static inline void __vm_flags_mod(struct vm_area_struct *vma,
859 				  vm_flags_t set, vm_flags_t clear)
860 {
861 	vm_flags_init(vma, (vma->vm_flags | set) & ~clear);
862 }
863 
864 /*
865  * Use only when the order of set/clear operations is unimportant, otherwise
866  * use vm_flags_{set|clear} explicitly.
867  */
vm_flags_mod(struct vm_area_struct * vma,vm_flags_t set,vm_flags_t clear)868 static inline void vm_flags_mod(struct vm_area_struct *vma,
869 				vm_flags_t set, vm_flags_t clear)
870 {
871 	vma_start_write(vma);
872 	__vm_flags_mod(vma, set, clear);
873 }
874 
vma_set_anonymous(struct vm_area_struct * vma)875 static inline void vma_set_anonymous(struct vm_area_struct *vma)
876 {
877 	vma->vm_ops = NULL;
878 }
879 
vma_is_anonymous(struct vm_area_struct * vma)880 static inline bool vma_is_anonymous(struct vm_area_struct *vma)
881 {
882 	return !vma->vm_ops;
883 }
884 
885 /*
886  * Indicate if the VMA is a heap for the given task; for
887  * /proc/PID/maps that is the heap of the main task.
888  */
vma_is_initial_heap(const struct vm_area_struct * vma)889 static inline bool vma_is_initial_heap(const struct vm_area_struct *vma)
890 {
891        return vma->vm_start <= vma->vm_mm->brk &&
892 		vma->vm_end >= vma->vm_mm->start_brk;
893 }
894 
895 /*
896  * Indicate if the VMA is a stack for the given task; for
897  * /proc/PID/maps that is the stack of the main task.
898  */
vma_is_initial_stack(const struct vm_area_struct * vma)899 static inline bool vma_is_initial_stack(const struct vm_area_struct *vma)
900 {
901 	/*
902 	 * We make no effort to guess what a given thread considers to be
903 	 * its "stack".  It's not even well-defined for programs written
904 	 * languages like Go.
905 	 */
906        return vma->vm_start <= vma->vm_mm->start_stack &&
907 	       vma->vm_end >= vma->vm_mm->start_stack;
908 }
909 
vma_is_temporary_stack(struct vm_area_struct * vma)910 static inline bool vma_is_temporary_stack(struct vm_area_struct *vma)
911 {
912 	int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP);
913 
914 	if (!maybe_stack)
915 		return false;
916 
917 	if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) ==
918 						VM_STACK_INCOMPLETE_SETUP)
919 		return true;
920 
921 	return false;
922 }
923 
vma_is_foreign(struct vm_area_struct * vma)924 static inline bool vma_is_foreign(struct vm_area_struct *vma)
925 {
926 	if (!current->mm)
927 		return true;
928 
929 	if (current->mm != vma->vm_mm)
930 		return true;
931 
932 	return false;
933 }
934 
vma_is_accessible(struct vm_area_struct * vma)935 static inline bool vma_is_accessible(struct vm_area_struct *vma)
936 {
937 	return vma->vm_flags & VM_ACCESS_FLAGS;
938 }
939 
940 static inline
vma_find(struct vma_iterator * vmi,unsigned long max)941 struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max)
942 {
943 	return mas_find(&vmi->mas, max - 1);
944 }
945 
vma_next(struct vma_iterator * vmi)946 static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi)
947 {
948 	/*
949 	 * Uses mas_find() to get the first VMA when the iterator starts.
950 	 * Calling mas_next() could skip the first entry.
951 	 */
952 	return mas_find(&vmi->mas, ULONG_MAX);
953 }
954 
955 static inline
vma_iter_next_range(struct vma_iterator * vmi)956 struct vm_area_struct *vma_iter_next_range(struct vma_iterator *vmi)
957 {
958 	return mas_next_range(&vmi->mas, ULONG_MAX);
959 }
960 
961 
vma_prev(struct vma_iterator * vmi)962 static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi)
963 {
964 	return mas_prev(&vmi->mas, 0);
965 }
966 
967 static inline
vma_iter_prev_range(struct vma_iterator * vmi)968 struct vm_area_struct *vma_iter_prev_range(struct vma_iterator *vmi)
969 {
970 	return mas_prev_range(&vmi->mas, 0);
971 }
972 
vma_iter_addr(struct vma_iterator * vmi)973 static inline unsigned long vma_iter_addr(struct vma_iterator *vmi)
974 {
975 	return vmi->mas.index;
976 }
977 
vma_iter_end(struct vma_iterator * vmi)978 static inline unsigned long vma_iter_end(struct vma_iterator *vmi)
979 {
980 	return vmi->mas.last + 1;
981 }
vma_iter_bulk_alloc(struct vma_iterator * vmi,unsigned long count)982 static inline int vma_iter_bulk_alloc(struct vma_iterator *vmi,
983 				      unsigned long count)
984 {
985 	return mas_expected_entries(&vmi->mas, count);
986 }
987 
988 /* Free any unused preallocations */
vma_iter_free(struct vma_iterator * vmi)989 static inline void vma_iter_free(struct vma_iterator *vmi)
990 {
991 	mas_destroy(&vmi->mas);
992 }
993 
vma_iter_bulk_store(struct vma_iterator * vmi,struct vm_area_struct * vma)994 static inline int vma_iter_bulk_store(struct vma_iterator *vmi,
995 				      struct vm_area_struct *vma)
996 {
997 	vmi->mas.index = vma->vm_start;
998 	vmi->mas.last = vma->vm_end - 1;
999 	mas_store(&vmi->mas, vma);
1000 	if (unlikely(mas_is_err(&vmi->mas)))
1001 		return -ENOMEM;
1002 
1003 	return 0;
1004 }
1005 
vma_iter_invalidate(struct vma_iterator * vmi)1006 static inline void vma_iter_invalidate(struct vma_iterator *vmi)
1007 {
1008 	mas_pause(&vmi->mas);
1009 }
1010 
vma_iter_set(struct vma_iterator * vmi,unsigned long addr)1011 static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr)
1012 {
1013 	mas_set(&vmi->mas, addr);
1014 }
1015 
1016 #define for_each_vma(__vmi, __vma)					\
1017 	while (((__vma) = vma_next(&(__vmi))) != NULL)
1018 
1019 /* The MM code likes to work with exclusive end addresses */
1020 #define for_each_vma_range(__vmi, __vma, __end)				\
1021 	while (((__vma) = vma_find(&(__vmi), (__end))) != NULL)
1022 
1023 #ifdef CONFIG_SHMEM
1024 /*
1025  * The vma_is_shmem is not inline because it is used only by slow
1026  * paths in userfault.
1027  */
1028 bool vma_is_shmem(struct vm_area_struct *vma);
1029 bool vma_is_anon_shmem(struct vm_area_struct *vma);
1030 #else
vma_is_shmem(struct vm_area_struct * vma)1031 static inline bool vma_is_shmem(struct vm_area_struct *vma) { return false; }
vma_is_anon_shmem(struct vm_area_struct * vma)1032 static inline bool vma_is_anon_shmem(struct vm_area_struct *vma) { return false; }
1033 #endif
1034 
1035 int vma_is_stack_for_current(struct vm_area_struct *vma);
1036 
1037 /* flush_tlb_range() takes a vma, not a mm, and can care about flags */
1038 #define TLB_FLUSH_VMA(mm,flags) { .vm_mm = (mm), .vm_flags = (flags) }
1039 
1040 struct mmu_gather;
1041 struct inode;
1042 
1043 /*
1044  * compound_order() can be called without holding a reference, which means
1045  * that niceties like page_folio() don't work.  These callers should be
1046  * prepared to handle wild return values.  For example, PG_head may be
1047  * set before the order is initialised, or this may be a tail page.
1048  * See compaction.c for some good examples.
1049  */
compound_order(struct page * page)1050 static inline unsigned int compound_order(struct page *page)
1051 {
1052 	struct folio *folio = (struct folio *)page;
1053 
1054 	if (!test_bit(PG_head, &folio->flags))
1055 		return 0;
1056 	return folio->_flags_1 & 0xff;
1057 }
1058 
1059 /**
1060  * folio_order - The allocation order of a folio.
1061  * @folio: The folio.
1062  *
1063  * A folio is composed of 2^order pages.  See get_order() for the definition
1064  * of order.
1065  *
1066  * Return: The order of the folio.
1067  */
folio_order(struct folio * folio)1068 static inline unsigned int folio_order(struct folio *folio)
1069 {
1070 	if (!folio_test_large(folio))
1071 		return 0;
1072 	return folio->_flags_1 & 0xff;
1073 }
1074 
1075 #include <linux/huge_mm.h>
1076 
1077 /*
1078  * Methods to modify the page usage count.
1079  *
1080  * What counts for a page usage:
1081  * - cache mapping   (page->mapping)
1082  * - private data    (page->private)
1083  * - page mapped in a task's page tables, each mapping
1084  *   is counted separately
1085  *
1086  * Also, many kernel routines increase the page count before a critical
1087  * routine so they can be sure the page doesn't go away from under them.
1088  */
1089 
1090 /*
1091  * Drop a ref, return true if the refcount fell to zero (the page has no users)
1092  */
put_page_testzero(struct page * page)1093 static inline int put_page_testzero(struct page *page)
1094 {
1095 	VM_BUG_ON_PAGE(page_ref_count(page) == 0, page);
1096 	return page_ref_dec_and_test(page);
1097 }
1098 
folio_put_testzero(struct folio * folio)1099 static inline int folio_put_testzero(struct folio *folio)
1100 {
1101 	return put_page_testzero(&folio->page);
1102 }
1103 
1104 /*
1105  * Try to grab a ref unless the page has a refcount of zero, return false if
1106  * that is the case.
1107  * This can be called when MMU is off so it must not access
1108  * any of the virtual mappings.
1109  */
get_page_unless_zero(struct page * page)1110 static inline bool get_page_unless_zero(struct page *page)
1111 {
1112 	return page_ref_add_unless(page, 1, 0);
1113 }
1114 
folio_get_nontail_page(struct page * page)1115 static inline struct folio *folio_get_nontail_page(struct page *page)
1116 {
1117 	if (unlikely(!get_page_unless_zero(page)))
1118 		return NULL;
1119 	return (struct folio *)page;
1120 }
1121 
1122 extern int page_is_ram(unsigned long pfn);
1123 
1124 enum {
1125 	REGION_INTERSECTS,
1126 	REGION_DISJOINT,
1127 	REGION_MIXED,
1128 };
1129 
1130 int region_intersects(resource_size_t offset, size_t size, unsigned long flags,
1131 		      unsigned long desc);
1132 
1133 /* Support for virtually mapped pages */
1134 struct page *vmalloc_to_page(const void *addr);
1135 unsigned long vmalloc_to_pfn(const void *addr);
1136 
1137 /*
1138  * Determine if an address is within the vmalloc range
1139  *
1140  * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
1141  * is no special casing required.
1142  */
1143 #ifdef CONFIG_MMU
1144 extern bool is_vmalloc_addr(const void *x);
1145 extern int is_vmalloc_or_module_addr(const void *x);
1146 #else
is_vmalloc_addr(const void * x)1147 static inline bool is_vmalloc_addr(const void *x)
1148 {
1149 	return false;
1150 }
is_vmalloc_or_module_addr(const void * x)1151 static inline int is_vmalloc_or_module_addr(const void *x)
1152 {
1153 	return 0;
1154 }
1155 #endif
1156 
1157 /*
1158  * How many times the entire folio is mapped as a single unit (eg by a
1159  * PMD or PUD entry).  This is probably not what you want, except for
1160  * debugging purposes - it does not include PTE-mapped sub-pages; look
1161  * at folio_mapcount() or page_mapcount() or total_mapcount() instead.
1162  */
folio_entire_mapcount(struct folio * folio)1163 static inline int folio_entire_mapcount(struct folio *folio)
1164 {
1165 	VM_BUG_ON_FOLIO(!folio_test_large(folio), folio);
1166 	return atomic_read(&folio->_entire_mapcount) + 1;
1167 }
1168 
1169 /*
1170  * The atomic page->_mapcount, starts from -1: so that transitions
1171  * both from it and to it can be tracked, using atomic_inc_and_test
1172  * and atomic_add_negative(-1).
1173  */
page_mapcount_reset(struct page * page)1174 static inline void page_mapcount_reset(struct page *page)
1175 {
1176 	atomic_set(&(page)->_mapcount, -1);
1177 }
1178 
1179 /**
1180  * page_mapcount() - Number of times this precise page is mapped.
1181  * @page: The page.
1182  *
1183  * The number of times this page is mapped.  If this page is part of
1184  * a large folio, it includes the number of times this page is mapped
1185  * as part of that folio.
1186  *
1187  * The result is undefined for pages which cannot be mapped into userspace.
1188  * For example SLAB or special types of pages. See function page_has_type().
1189  * They use this field in struct page differently.
1190  */
page_mapcount(struct page * page)1191 static inline int page_mapcount(struct page *page)
1192 {
1193 	int mapcount = atomic_read(&page->_mapcount) + 1;
1194 
1195 	if (unlikely(PageCompound(page)))
1196 		mapcount += folio_entire_mapcount(page_folio(page));
1197 
1198 	return mapcount;
1199 }
1200 
1201 int folio_total_mapcount(struct folio *folio);
1202 
1203 /**
1204  * folio_mapcount() - Calculate the number of mappings of this folio.
1205  * @folio: The folio.
1206  *
1207  * A large folio tracks both how many times the entire folio is mapped,
1208  * and how many times each individual page in the folio is mapped.
1209  * This function calculates the total number of times the folio is
1210  * mapped.
1211  *
1212  * Return: The number of times this folio is mapped.
1213  */
folio_mapcount(struct folio * folio)1214 static inline int folio_mapcount(struct folio *folio)
1215 {
1216 	if (likely(!folio_test_large(folio)))
1217 		return atomic_read(&folio->_mapcount) + 1;
1218 	return folio_total_mapcount(folio);
1219 }
1220 
total_mapcount(struct page * page)1221 static inline int total_mapcount(struct page *page)
1222 {
1223 	if (likely(!PageCompound(page)))
1224 		return atomic_read(&page->_mapcount) + 1;
1225 	return folio_total_mapcount(page_folio(page));
1226 }
1227 
folio_large_is_mapped(struct folio * folio)1228 static inline bool folio_large_is_mapped(struct folio *folio)
1229 {
1230 	/*
1231 	 * Reading _entire_mapcount below could be omitted if hugetlb
1232 	 * participated in incrementing nr_pages_mapped when compound mapped.
1233 	 */
1234 	return atomic_read(&folio->_nr_pages_mapped) > 0 ||
1235 		atomic_read(&folio->_entire_mapcount) >= 0;
1236 }
1237 
1238 /**
1239  * folio_mapped - Is this folio mapped into userspace?
1240  * @folio: The folio.
1241  *
1242  * Return: True if any page in this folio is referenced by user page tables.
1243  */
folio_mapped(struct folio * folio)1244 static inline bool folio_mapped(struct folio *folio)
1245 {
1246 	if (likely(!folio_test_large(folio)))
1247 		return atomic_read(&folio->_mapcount) >= 0;
1248 	return folio_large_is_mapped(folio);
1249 }
1250 
1251 /*
1252  * Return true if this page is mapped into pagetables.
1253  * For compound page it returns true if any sub-page of compound page is mapped,
1254  * even if this particular sub-page is not itself mapped by any PTE or PMD.
1255  */
page_mapped(struct page * page)1256 static inline bool page_mapped(struct page *page)
1257 {
1258 	if (likely(!PageCompound(page)))
1259 		return atomic_read(&page->_mapcount) >= 0;
1260 	return folio_large_is_mapped(page_folio(page));
1261 }
1262 
virt_to_head_page(const void * x)1263 static inline struct page *virt_to_head_page(const void *x)
1264 {
1265 	struct page *page = virt_to_page(x);
1266 
1267 	return compound_head(page);
1268 }
1269 
virt_to_folio(const void * x)1270 static inline struct folio *virt_to_folio(const void *x)
1271 {
1272 	struct page *page = virt_to_page(x);
1273 
1274 	return page_folio(page);
1275 }
1276 
1277 void __folio_put(struct folio *folio);
1278 
1279 void put_pages_list(struct list_head *pages);
1280 
1281 void split_page(struct page *page, unsigned int order);
1282 void folio_copy(struct folio *dst, struct folio *src);
1283 
1284 unsigned long nr_free_buffer_pages(void);
1285 
1286 void destroy_large_folio(struct folio *folio);
1287 
1288 /* Returns the number of bytes in this potentially compound page. */
page_size(struct page * page)1289 static inline unsigned long page_size(struct page *page)
1290 {
1291 	return PAGE_SIZE << compound_order(page);
1292 }
1293 
1294 /* Returns the number of bits needed for the number of bytes in a page */
page_shift(struct page * page)1295 static inline unsigned int page_shift(struct page *page)
1296 {
1297 	return PAGE_SHIFT + compound_order(page);
1298 }
1299 
1300 /**
1301  * thp_order - Order of a transparent huge page.
1302  * @page: Head page of a transparent huge page.
1303  */
thp_order(struct page * page)1304 static inline unsigned int thp_order(struct page *page)
1305 {
1306 	VM_BUG_ON_PGFLAGS(PageTail(page), page);
1307 	return compound_order(page);
1308 }
1309 
1310 /**
1311  * thp_size - Size of a transparent huge page.
1312  * @page: Head page of a transparent huge page.
1313  *
1314  * Return: Number of bytes in this page.
1315  */
thp_size(struct page * page)1316 static inline unsigned long thp_size(struct page *page)
1317 {
1318 	return PAGE_SIZE << thp_order(page);
1319 }
1320 
1321 #ifdef CONFIG_MMU
1322 /*
1323  * Do pte_mkwrite, but only if the vma says VM_WRITE.  We do this when
1324  * servicing faults for write access.  In the normal case, do always want
1325  * pte_mkwrite.  But get_user_pages can cause write faults for mappings
1326  * that do not have writing enabled, when used by access_process_vm.
1327  */
maybe_mkwrite(pte_t pte,struct vm_area_struct * vma)1328 static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
1329 {
1330 	if (likely(vma->vm_flags & VM_WRITE))
1331 		pte = pte_mkwrite(pte, vma);
1332 	return pte;
1333 }
1334 
1335 vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page);
1336 void set_pte_range(struct vm_fault *vmf, struct folio *folio,
1337 		struct page *page, unsigned int nr, unsigned long addr);
1338 
1339 vm_fault_t finish_fault(struct vm_fault *vmf);
1340 vm_fault_t finish_mkwrite_fault(struct vm_fault *vmf);
1341 #endif
1342 
1343 /*
1344  * Multiple processes may "see" the same page. E.g. for untouched
1345  * mappings of /dev/null, all processes see the same page full of
1346  * zeroes, and text pages of executables and shared libraries have
1347  * only one copy in memory, at most, normally.
1348  *
1349  * For the non-reserved pages, page_count(page) denotes a reference count.
1350  *   page_count() == 0 means the page is free. page->lru is then used for
1351  *   freelist management in the buddy allocator.
1352  *   page_count() > 0  means the page has been allocated.
1353  *
1354  * Pages are allocated by the slab allocator in order to provide memory
1355  * to kmalloc and kmem_cache_alloc. In this case, the management of the
1356  * page, and the fields in 'struct page' are the responsibility of mm/slab.c
1357  * unless a particular usage is carefully commented. (the responsibility of
1358  * freeing the kmalloc memory is the caller's, of course).
1359  *
1360  * A page may be used by anyone else who does a __get_free_page().
1361  * In this case, page_count still tracks the references, and should only
1362  * be used through the normal accessor functions. The top bits of page->flags
1363  * and page->virtual store page management information, but all other fields
1364  * are unused and could be used privately, carefully. The management of this
1365  * page is the responsibility of the one who allocated it, and those who have
1366  * subsequently been given references to it.
1367  *
1368  * The other pages (we may call them "pagecache pages") are completely
1369  * managed by the Linux memory manager: I/O, buffers, swapping etc.
1370  * The following discussion applies only to them.
1371  *
1372  * A pagecache page contains an opaque `private' member, which belongs to the
1373  * page's address_space. Usually, this is the address of a circular list of
1374  * the page's disk buffers. PG_private must be set to tell the VM to call
1375  * into the filesystem to release these pages.
1376  *
1377  * A page may belong to an inode's memory mapping. In this case, page->mapping
1378  * is the pointer to the inode, and page->index is the file offset of the page,
1379  * in units of PAGE_SIZE.
1380  *
1381  * If pagecache pages are not associated with an inode, they are said to be
1382  * anonymous pages. These may become associated with the swapcache, and in that
1383  * case PG_swapcache is set, and page->private is an offset into the swapcache.
1384  *
1385  * In either case (swapcache or inode backed), the pagecache itself holds one
1386  * reference to the page. Setting PG_private should also increment the
1387  * refcount. The each user mapping also has a reference to the page.
1388  *
1389  * The pagecache pages are stored in a per-mapping radix tree, which is
1390  * rooted at mapping->i_pages, and indexed by offset.
1391  * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space
1392  * lists, we instead now tag pages as dirty/writeback in the radix tree.
1393  *
1394  * All pagecache pages may be subject to I/O:
1395  * - inode pages may need to be read from disk,
1396  * - inode pages which have been modified and are MAP_SHARED may need
1397  *   to be written back to the inode on disk,
1398  * - anonymous pages (including MAP_PRIVATE file mappings) which have been
1399  *   modified may need to be swapped out to swap space and (later) to be read
1400  *   back into memory.
1401  */
1402 
1403 #if defined(CONFIG_ZONE_DEVICE) && defined(CONFIG_FS_DAX)
1404 DECLARE_STATIC_KEY_FALSE(devmap_managed_key);
1405 
1406 bool __put_devmap_managed_page_refs(struct page *page, int refs);
put_devmap_managed_page_refs(struct page * page,int refs)1407 static inline bool put_devmap_managed_page_refs(struct page *page, int refs)
1408 {
1409 	if (!static_branch_unlikely(&devmap_managed_key))
1410 		return false;
1411 	if (!is_zone_device_page(page))
1412 		return false;
1413 	return __put_devmap_managed_page_refs(page, refs);
1414 }
1415 #else /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
put_devmap_managed_page_refs(struct page * page,int refs)1416 static inline bool put_devmap_managed_page_refs(struct page *page, int refs)
1417 {
1418 	return false;
1419 }
1420 #endif /* CONFIG_ZONE_DEVICE && CONFIG_FS_DAX */
1421 
put_devmap_managed_page(struct page * page)1422 static inline bool put_devmap_managed_page(struct page *page)
1423 {
1424 	return put_devmap_managed_page_refs(page, 1);
1425 }
1426 
1427 /* 127: arbitrary random number, small enough to assemble well */
1428 #define folio_ref_zero_or_close_to_overflow(folio) \
1429 	((unsigned int) folio_ref_count(folio) + 127u <= 127u)
1430 
1431 /**
1432  * folio_get - Increment the reference count on a folio.
1433  * @folio: The folio.
1434  *
1435  * Context: May be called in any context, as long as you know that
1436  * you have a refcount on the folio.  If you do not already have one,
1437  * folio_try_get() may be the right interface for you to use.
1438  */
folio_get(struct folio * folio)1439 static inline void folio_get(struct folio *folio)
1440 {
1441 	VM_BUG_ON_FOLIO(folio_ref_zero_or_close_to_overflow(folio), folio);
1442 	folio_ref_inc(folio);
1443 }
1444 
get_page(struct page * page)1445 static inline void get_page(struct page *page)
1446 {
1447 	folio_get(page_folio(page));
1448 }
1449 
try_get_page(struct page * page)1450 static inline __must_check bool try_get_page(struct page *page)
1451 {
1452 	page = compound_head(page);
1453 	if (WARN_ON_ONCE(page_ref_count(page) <= 0))
1454 		return false;
1455 	page_ref_inc(page);
1456 	return true;
1457 }
1458 
1459 /**
1460  * folio_put - Decrement the reference count on a folio.
1461  * @folio: The folio.
1462  *
1463  * If the folio's reference count reaches zero, the memory will be
1464  * released back to the page allocator and may be used by another
1465  * allocation immediately.  Do not access the memory or the struct folio
1466  * after calling folio_put() unless you can be sure that it wasn't the
1467  * last reference.
1468  *
1469  * Context: May be called in process or interrupt context, but not in NMI
1470  * context.  May be called while holding a spinlock.
1471  */
folio_put(struct folio * folio)1472 static inline void folio_put(struct folio *folio)
1473 {
1474 	if (folio_put_testzero(folio))
1475 		__folio_put(folio);
1476 }
1477 
1478 /**
1479  * folio_put_refs - Reduce the reference count on a folio.
1480  * @folio: The folio.
1481  * @refs: The amount to subtract from the folio's reference count.
1482  *
1483  * If the folio's reference count reaches zero, the memory will be
1484  * released back to the page allocator and may be used by another
1485  * allocation immediately.  Do not access the memory or the struct folio
1486  * after calling folio_put_refs() unless you can be sure that these weren't
1487  * the last references.
1488  *
1489  * Context: May be called in process or interrupt context, but not in NMI
1490  * context.  May be called while holding a spinlock.
1491  */
folio_put_refs(struct folio * folio,int refs)1492 static inline void folio_put_refs(struct folio *folio, int refs)
1493 {
1494 	if (folio_ref_sub_and_test(folio, refs))
1495 		__folio_put(folio);
1496 }
1497 
1498 /*
1499  * union release_pages_arg - an array of pages or folios
1500  *
1501  * release_pages() releases a simple array of multiple pages, and
1502  * accepts various different forms of said page array: either
1503  * a regular old boring array of pages, an array of folios, or
1504  * an array of encoded page pointers.
1505  *
1506  * The transparent union syntax for this kind of "any of these
1507  * argument types" is all kinds of ugly, so look away.
1508  */
1509 typedef union {
1510 	struct page **pages;
1511 	struct folio **folios;
1512 	struct encoded_page **encoded_pages;
1513 } release_pages_arg __attribute__ ((__transparent_union__));
1514 
1515 void release_pages(release_pages_arg, int nr);
1516 
1517 /**
1518  * folios_put - Decrement the reference count on an array of folios.
1519  * @folios: The folios.
1520  * @nr: How many folios there are.
1521  *
1522  * Like folio_put(), but for an array of folios.  This is more efficient
1523  * than writing the loop yourself as it will optimise the locks which
1524  * need to be taken if the folios are freed.
1525  *
1526  * Context: May be called in process or interrupt context, but not in NMI
1527  * context.  May be called while holding a spinlock.
1528  */
folios_put(struct folio ** folios,unsigned int nr)1529 static inline void folios_put(struct folio **folios, unsigned int nr)
1530 {
1531 	release_pages(folios, nr);
1532 }
1533 
put_page(struct page * page)1534 static inline void put_page(struct page *page)
1535 {
1536 	struct folio *folio = page_folio(page);
1537 
1538 	/*
1539 	 * For some devmap managed pages we need to catch refcount transition
1540 	 * from 2 to 1:
1541 	 */
1542 	if (put_devmap_managed_page(&folio->page))
1543 		return;
1544 	folio_put(folio);
1545 }
1546 
1547 /*
1548  * GUP_PIN_COUNTING_BIAS, and the associated functions that use it, overload
1549  * the page's refcount so that two separate items are tracked: the original page
1550  * reference count, and also a new count of how many pin_user_pages() calls were
1551  * made against the page. ("gup-pinned" is another term for the latter).
1552  *
1553  * With this scheme, pin_user_pages() becomes special: such pages are marked as
1554  * distinct from normal pages. As such, the unpin_user_page() call (and its
1555  * variants) must be used in order to release gup-pinned pages.
1556  *
1557  * Choice of value:
1558  *
1559  * By making GUP_PIN_COUNTING_BIAS a power of two, debugging of page reference
1560  * counts with respect to pin_user_pages() and unpin_user_page() becomes
1561  * simpler, due to the fact that adding an even power of two to the page
1562  * refcount has the effect of using only the upper N bits, for the code that
1563  * counts up using the bias value. This means that the lower bits are left for
1564  * the exclusive use of the original code that increments and decrements by one
1565  * (or at least, by much smaller values than the bias value).
1566  *
1567  * Of course, once the lower bits overflow into the upper bits (and this is
1568  * OK, because subtraction recovers the original values), then visual inspection
1569  * no longer suffices to directly view the separate counts. However, for normal
1570  * applications that don't have huge page reference counts, this won't be an
1571  * issue.
1572  *
1573  * Locking: the lockless algorithm described in folio_try_get_rcu()
1574  * provides safe operation for get_user_pages(), page_mkclean() and
1575  * other calls that race to set up page table entries.
1576  */
1577 #define GUP_PIN_COUNTING_BIAS (1U << 10)
1578 
1579 void unpin_user_page(struct page *page);
1580 void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages,
1581 				 bool make_dirty);
1582 void unpin_user_page_range_dirty_lock(struct page *page, unsigned long npages,
1583 				      bool make_dirty);
1584 void unpin_user_pages(struct page **pages, unsigned long npages);
1585 
is_cow_mapping(vm_flags_t flags)1586 static inline bool is_cow_mapping(vm_flags_t flags)
1587 {
1588 	return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
1589 }
1590 
1591 #ifndef CONFIG_MMU
is_nommu_shared_mapping(vm_flags_t flags)1592 static inline bool is_nommu_shared_mapping(vm_flags_t flags)
1593 {
1594 	/*
1595 	 * NOMMU shared mappings are ordinary MAP_SHARED mappings and selected
1596 	 * R/O MAP_PRIVATE file mappings that are an effective R/O overlay of
1597 	 * a file mapping. R/O MAP_PRIVATE mappings might still modify
1598 	 * underlying memory if ptrace is active, so this is only possible if
1599 	 * ptrace does not apply. Note that there is no mprotect() to upgrade
1600 	 * write permissions later.
1601 	 */
1602 	return flags & (VM_MAYSHARE | VM_MAYOVERLAY);
1603 }
1604 #endif
1605 
1606 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
1607 #define SECTION_IN_PAGE_FLAGS
1608 #endif
1609 
1610 /*
1611  * The identification function is mainly used by the buddy allocator for
1612  * determining if two pages could be buddies. We are not really identifying
1613  * the zone since we could be using the section number id if we do not have
1614  * node id available in page flags.
1615  * We only guarantee that it will return the same value for two combinable
1616  * pages in a zone.
1617  */
page_zone_id(struct page * page)1618 static inline int page_zone_id(struct page *page)
1619 {
1620 	return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK;
1621 }
1622 
1623 #ifdef NODE_NOT_IN_PAGE_FLAGS
1624 extern int page_to_nid(const struct page *page);
1625 #else
page_to_nid(const struct page * page)1626 static inline int page_to_nid(const struct page *page)
1627 {
1628 	struct page *p = (struct page *)page;
1629 
1630 	return (PF_POISONED_CHECK(p)->flags >> NODES_PGSHIFT) & NODES_MASK;
1631 }
1632 #endif
1633 
folio_nid(const struct folio * folio)1634 static inline int folio_nid(const struct folio *folio)
1635 {
1636 	return page_to_nid(&folio->page);
1637 }
1638 
1639 #ifdef CONFIG_NUMA_BALANCING
1640 /* page access time bits needs to hold at least 4 seconds */
1641 #define PAGE_ACCESS_TIME_MIN_BITS	12
1642 #if LAST_CPUPID_SHIFT < PAGE_ACCESS_TIME_MIN_BITS
1643 #define PAGE_ACCESS_TIME_BUCKETS				\
1644 	(PAGE_ACCESS_TIME_MIN_BITS - LAST_CPUPID_SHIFT)
1645 #else
1646 #define PAGE_ACCESS_TIME_BUCKETS	0
1647 #endif
1648 
1649 #define PAGE_ACCESS_TIME_MASK				\
1650 	(LAST_CPUPID_MASK << PAGE_ACCESS_TIME_BUCKETS)
1651 
cpu_pid_to_cpupid(int cpu,int pid)1652 static inline int cpu_pid_to_cpupid(int cpu, int pid)
1653 {
1654 	return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK);
1655 }
1656 
cpupid_to_pid(int cpupid)1657 static inline int cpupid_to_pid(int cpupid)
1658 {
1659 	return cpupid & LAST__PID_MASK;
1660 }
1661 
cpupid_to_cpu(int cpupid)1662 static inline int cpupid_to_cpu(int cpupid)
1663 {
1664 	return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK;
1665 }
1666 
cpupid_to_nid(int cpupid)1667 static inline int cpupid_to_nid(int cpupid)
1668 {
1669 	return cpu_to_node(cpupid_to_cpu(cpupid));
1670 }
1671 
cpupid_pid_unset(int cpupid)1672 static inline bool cpupid_pid_unset(int cpupid)
1673 {
1674 	return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK);
1675 }
1676 
cpupid_cpu_unset(int cpupid)1677 static inline bool cpupid_cpu_unset(int cpupid)
1678 {
1679 	return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK);
1680 }
1681 
__cpupid_match_pid(pid_t task_pid,int cpupid)1682 static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid)
1683 {
1684 	return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid);
1685 }
1686 
1687 #define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid)
1688 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
page_cpupid_xchg_last(struct page * page,int cpupid)1689 static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1690 {
1691 	return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK);
1692 }
1693 
page_cpupid_last(struct page * page)1694 static inline int page_cpupid_last(struct page *page)
1695 {
1696 	return page->_last_cpupid;
1697 }
page_cpupid_reset_last(struct page * page)1698 static inline void page_cpupid_reset_last(struct page *page)
1699 {
1700 	page->_last_cpupid = -1 & LAST_CPUPID_MASK;
1701 }
1702 #else
page_cpupid_last(struct page * page)1703 static inline int page_cpupid_last(struct page *page)
1704 {
1705 	return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
1706 }
1707 
1708 extern int page_cpupid_xchg_last(struct page *page, int cpupid);
1709 
page_cpupid_reset_last(struct page * page)1710 static inline void page_cpupid_reset_last(struct page *page)
1711 {
1712 	page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT;
1713 }
1714 #endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
1715 
xchg_page_access_time(struct page * page,int time)1716 static inline int xchg_page_access_time(struct page *page, int time)
1717 {
1718 	int last_time;
1719 
1720 	last_time = page_cpupid_xchg_last(page, time >> PAGE_ACCESS_TIME_BUCKETS);
1721 	return last_time << PAGE_ACCESS_TIME_BUCKETS;
1722 }
1723 
vma_set_access_pid_bit(struct vm_area_struct * vma)1724 static inline void vma_set_access_pid_bit(struct vm_area_struct *vma)
1725 {
1726 	unsigned int pid_bit;
1727 
1728 	pid_bit = hash_32(current->pid, ilog2(BITS_PER_LONG));
1729 	if (vma->numab_state && !test_bit(pid_bit, &vma->numab_state->access_pids[1])) {
1730 		__set_bit(pid_bit, &vma->numab_state->access_pids[1]);
1731 	}
1732 }
1733 #else /* !CONFIG_NUMA_BALANCING */
page_cpupid_xchg_last(struct page * page,int cpupid)1734 static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
1735 {
1736 	return page_to_nid(page); /* XXX */
1737 }
1738 
xchg_page_access_time(struct page * page,int time)1739 static inline int xchg_page_access_time(struct page *page, int time)
1740 {
1741 	return 0;
1742 }
1743 
page_cpupid_last(struct page * page)1744 static inline int page_cpupid_last(struct page *page)
1745 {
1746 	return page_to_nid(page); /* XXX */
1747 }
1748 
cpupid_to_nid(int cpupid)1749 static inline int cpupid_to_nid(int cpupid)
1750 {
1751 	return -1;
1752 }
1753 
cpupid_to_pid(int cpupid)1754 static inline int cpupid_to_pid(int cpupid)
1755 {
1756 	return -1;
1757 }
1758 
cpupid_to_cpu(int cpupid)1759 static inline int cpupid_to_cpu(int cpupid)
1760 {
1761 	return -1;
1762 }
1763 
cpu_pid_to_cpupid(int nid,int pid)1764 static inline int cpu_pid_to_cpupid(int nid, int pid)
1765 {
1766 	return -1;
1767 }
1768 
cpupid_pid_unset(int cpupid)1769 static inline bool cpupid_pid_unset(int cpupid)
1770 {
1771 	return true;
1772 }
1773 
page_cpupid_reset_last(struct page * page)1774 static inline void page_cpupid_reset_last(struct page *page)
1775 {
1776 }
1777 
cpupid_match_pid(struct task_struct * task,int cpupid)1778 static inline bool cpupid_match_pid(struct task_struct *task, int cpupid)
1779 {
1780 	return false;
1781 }
1782 
vma_set_access_pid_bit(struct vm_area_struct * vma)1783 static inline void vma_set_access_pid_bit(struct vm_area_struct *vma)
1784 {
1785 }
1786 #endif /* CONFIG_NUMA_BALANCING */
1787 
1788 #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
1789 
1790 /*
1791  * KASAN per-page tags are stored xor'ed with 0xff. This allows to avoid
1792  * setting tags for all pages to native kernel tag value 0xff, as the default
1793  * value 0x00 maps to 0xff.
1794  */
1795 
page_kasan_tag(const struct page * page)1796 static inline u8 page_kasan_tag(const struct page *page)
1797 {
1798 	u8 tag = 0xff;
1799 
1800 	if (kasan_enabled()) {
1801 		tag = (page->flags >> KASAN_TAG_PGSHIFT) & KASAN_TAG_MASK;
1802 		tag ^= 0xff;
1803 	}
1804 
1805 	return tag;
1806 }
1807 
page_kasan_tag_set(struct page * page,u8 tag)1808 static inline void page_kasan_tag_set(struct page *page, u8 tag)
1809 {
1810 	unsigned long old_flags, flags;
1811 
1812 	if (!kasan_enabled())
1813 		return;
1814 
1815 	tag ^= 0xff;
1816 	old_flags = READ_ONCE(page->flags);
1817 	do {
1818 		flags = old_flags;
1819 		flags &= ~(KASAN_TAG_MASK << KASAN_TAG_PGSHIFT);
1820 		flags |= (tag & KASAN_TAG_MASK) << KASAN_TAG_PGSHIFT;
1821 	} while (unlikely(!try_cmpxchg(&page->flags, &old_flags, flags)));
1822 }
1823 
page_kasan_tag_reset(struct page * page)1824 static inline void page_kasan_tag_reset(struct page *page)
1825 {
1826 	if (kasan_enabled())
1827 		page_kasan_tag_set(page, 0xff);
1828 }
1829 
1830 #else /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
1831 
page_kasan_tag(const struct page * page)1832 static inline u8 page_kasan_tag(const struct page *page)
1833 {
1834 	return 0xff;
1835 }
1836 
page_kasan_tag_set(struct page * page,u8 tag)1837 static inline void page_kasan_tag_set(struct page *page, u8 tag) { }
page_kasan_tag_reset(struct page * page)1838 static inline void page_kasan_tag_reset(struct page *page) { }
1839 
1840 #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
1841 
page_zone(const struct page * page)1842 static inline struct zone *page_zone(const struct page *page)
1843 {
1844 	return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)];
1845 }
1846 
page_pgdat(const struct page * page)1847 static inline pg_data_t *page_pgdat(const struct page *page)
1848 {
1849 	return NODE_DATA(page_to_nid(page));
1850 }
1851 
folio_zone(const struct folio * folio)1852 static inline struct zone *folio_zone(const struct folio *folio)
1853 {
1854 	return page_zone(&folio->page);
1855 }
1856 
folio_pgdat(const struct folio * folio)1857 static inline pg_data_t *folio_pgdat(const struct folio *folio)
1858 {
1859 	return page_pgdat(&folio->page);
1860 }
1861 
1862 #ifdef SECTION_IN_PAGE_FLAGS
set_page_section(struct page * page,unsigned long section)1863 static inline void set_page_section(struct page *page, unsigned long section)
1864 {
1865 	page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT);
1866 	page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT;
1867 }
1868 
page_to_section(const struct page * page)1869 static inline unsigned long page_to_section(const struct page *page)
1870 {
1871 	return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK;
1872 }
1873 #endif
1874 
1875 /**
1876  * folio_pfn - Return the Page Frame Number of a folio.
1877  * @folio: The folio.
1878  *
1879  * A folio may contain multiple pages.  The pages have consecutive
1880  * Page Frame Numbers.
1881  *
1882  * Return: The Page Frame Number of the first page in the folio.
1883  */
folio_pfn(struct folio * folio)1884 static inline unsigned long folio_pfn(struct folio *folio)
1885 {
1886 	return page_to_pfn(&folio->page);
1887 }
1888 
pfn_folio(unsigned long pfn)1889 static inline struct folio *pfn_folio(unsigned long pfn)
1890 {
1891 	return page_folio(pfn_to_page(pfn));
1892 }
1893 
1894 /**
1895  * folio_maybe_dma_pinned - Report if a folio may be pinned for DMA.
1896  * @folio: The folio.
1897  *
1898  * This function checks if a folio has been pinned via a call to
1899  * a function in the pin_user_pages() family.
1900  *
1901  * For small folios, the return value is partially fuzzy: false is not fuzzy,
1902  * because it means "definitely not pinned for DMA", but true means "probably
1903  * pinned for DMA, but possibly a false positive due to having at least
1904  * GUP_PIN_COUNTING_BIAS worth of normal folio references".
1905  *
1906  * False positives are OK, because: a) it's unlikely for a folio to
1907  * get that many refcounts, and b) all the callers of this routine are
1908  * expected to be able to deal gracefully with a false positive.
1909  *
1910  * For large folios, the result will be exactly correct. That's because
1911  * we have more tracking data available: the _pincount field is used
1912  * instead of the GUP_PIN_COUNTING_BIAS scheme.
1913  *
1914  * For more information, please see Documentation/core-api/pin_user_pages.rst.
1915  *
1916  * Return: True, if it is likely that the page has been "dma-pinned".
1917  * False, if the page is definitely not dma-pinned.
1918  */
folio_maybe_dma_pinned(struct folio * folio)1919 static inline bool folio_maybe_dma_pinned(struct folio *folio)
1920 {
1921 	if (folio_test_large(folio))
1922 		return atomic_read(&folio->_pincount) > 0;
1923 
1924 	/*
1925 	 * folio_ref_count() is signed. If that refcount overflows, then
1926 	 * folio_ref_count() returns a negative value, and callers will avoid
1927 	 * further incrementing the refcount.
1928 	 *
1929 	 * Here, for that overflow case, use the sign bit to count a little
1930 	 * bit higher via unsigned math, and thus still get an accurate result.
1931 	 */
1932 	return ((unsigned int)folio_ref_count(folio)) >=
1933 		GUP_PIN_COUNTING_BIAS;
1934 }
1935 
page_maybe_dma_pinned(struct page * page)1936 static inline bool page_maybe_dma_pinned(struct page *page)
1937 {
1938 	return folio_maybe_dma_pinned(page_folio(page));
1939 }
1940 
1941 /*
1942  * This should most likely only be called during fork() to see whether we
1943  * should break the cow immediately for an anon page on the src mm.
1944  *
1945  * The caller has to hold the PT lock and the vma->vm_mm->->write_protect_seq.
1946  */
page_needs_cow_for_dma(struct vm_area_struct * vma,struct page * page)1947 static inline bool page_needs_cow_for_dma(struct vm_area_struct *vma,
1948 					  struct page *page)
1949 {
1950 	VM_BUG_ON(!(raw_read_seqcount(&vma->vm_mm->write_protect_seq) & 1));
1951 
1952 	if (!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))
1953 		return false;
1954 
1955 	return page_maybe_dma_pinned(page);
1956 }
1957 
1958 /**
1959  * is_zero_page - Query if a page is a zero page
1960  * @page: The page to query
1961  *
1962  * This returns true if @page is one of the permanent zero pages.
1963  */
is_zero_page(const struct page * page)1964 static inline bool is_zero_page(const struct page *page)
1965 {
1966 	return is_zero_pfn(page_to_pfn(page));
1967 }
1968 
1969 /**
1970  * is_zero_folio - Query if a folio is a zero page
1971  * @folio: The folio to query
1972  *
1973  * This returns true if @folio is one of the permanent zero pages.
1974  */
is_zero_folio(const struct folio * folio)1975 static inline bool is_zero_folio(const struct folio *folio)
1976 {
1977 	return is_zero_page(&folio->page);
1978 }
1979 
1980 /* MIGRATE_CMA and ZONE_MOVABLE do not allow pin folios */
1981 #ifdef CONFIG_MIGRATION
folio_is_longterm_pinnable(struct folio * folio)1982 static inline bool folio_is_longterm_pinnable(struct folio *folio)
1983 {
1984 #ifdef CONFIG_CMA
1985 	int mt = folio_migratetype(folio);
1986 
1987 	if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE)
1988 		return false;
1989 #endif
1990 	/* The zero page can be "pinned" but gets special handling. */
1991 	if (is_zero_folio(folio))
1992 		return true;
1993 
1994 	/* Coherent device memory must always allow eviction. */
1995 	if (folio_is_device_coherent(folio))
1996 		return false;
1997 
1998 	/* Otherwise, non-movable zone folios can be pinned. */
1999 	return !folio_is_zone_movable(folio);
2000 
2001 }
2002 #else
folio_is_longterm_pinnable(struct folio * folio)2003 static inline bool folio_is_longterm_pinnable(struct folio *folio)
2004 {
2005 	return true;
2006 }
2007 #endif
2008 
set_page_zone(struct page * page,enum zone_type zone)2009 static inline void set_page_zone(struct page *page, enum zone_type zone)
2010 {
2011 	page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT);
2012 	page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT;
2013 }
2014 
set_page_node(struct page * page,unsigned long node)2015 static inline void set_page_node(struct page *page, unsigned long node)
2016 {
2017 	page->flags &= ~(NODES_MASK << NODES_PGSHIFT);
2018 	page->flags |= (node & NODES_MASK) << NODES_PGSHIFT;
2019 }
2020 
set_page_links(struct page * page,enum zone_type zone,unsigned long node,unsigned long pfn)2021 static inline void set_page_links(struct page *page, enum zone_type zone,
2022 	unsigned long node, unsigned long pfn)
2023 {
2024 	set_page_zone(page, zone);
2025 	set_page_node(page, node);
2026 #ifdef SECTION_IN_PAGE_FLAGS
2027 	set_page_section(page, pfn_to_section_nr(pfn));
2028 #endif
2029 }
2030 
2031 /**
2032  * folio_nr_pages - The number of pages in the folio.
2033  * @folio: The folio.
2034  *
2035  * Return: A positive power of two.
2036  */
folio_nr_pages(struct folio * folio)2037 static inline long folio_nr_pages(struct folio *folio)
2038 {
2039 	if (!folio_test_large(folio))
2040 		return 1;
2041 #ifdef CONFIG_64BIT
2042 	return folio->_folio_nr_pages;
2043 #else
2044 	return 1L << (folio->_flags_1 & 0xff);
2045 #endif
2046 }
2047 
2048 /*
2049  * compound_nr() returns the number of pages in this potentially compound
2050  * page.  compound_nr() can be called on a tail page, and is defined to
2051  * return 1 in that case.
2052  */
compound_nr(struct page * page)2053 static inline unsigned long compound_nr(struct page *page)
2054 {
2055 	struct folio *folio = (struct folio *)page;
2056 
2057 	if (!test_bit(PG_head, &folio->flags))
2058 		return 1;
2059 #ifdef CONFIG_64BIT
2060 	return folio->_folio_nr_pages;
2061 #else
2062 	return 1L << (folio->_flags_1 & 0xff);
2063 #endif
2064 }
2065 
2066 /**
2067  * thp_nr_pages - The number of regular pages in this huge page.
2068  * @page: The head page of a huge page.
2069  */
thp_nr_pages(struct page * page)2070 static inline int thp_nr_pages(struct page *page)
2071 {
2072 	return folio_nr_pages((struct folio *)page);
2073 }
2074 
2075 /**
2076  * folio_next - Move to the next physical folio.
2077  * @folio: The folio we're currently operating on.
2078  *
2079  * If you have physically contiguous memory which may span more than
2080  * one folio (eg a &struct bio_vec), use this function to move from one
2081  * folio to the next.  Do not use it if the memory is only virtually
2082  * contiguous as the folios are almost certainly not adjacent to each
2083  * other.  This is the folio equivalent to writing ``page++``.
2084  *
2085  * Context: We assume that the folios are refcounted and/or locked at a
2086  * higher level and do not adjust the reference counts.
2087  * Return: The next struct folio.
2088  */
folio_next(struct folio * folio)2089 static inline struct folio *folio_next(struct folio *folio)
2090 {
2091 	return (struct folio *)folio_page(folio, folio_nr_pages(folio));
2092 }
2093 
2094 /**
2095  * folio_shift - The size of the memory described by this folio.
2096  * @folio: The folio.
2097  *
2098  * A folio represents a number of bytes which is a power-of-two in size.
2099  * This function tells you which power-of-two the folio is.  See also
2100  * folio_size() and folio_order().
2101  *
2102  * Context: The caller should have a reference on the folio to prevent
2103  * it from being split.  It is not necessary for the folio to be locked.
2104  * Return: The base-2 logarithm of the size of this folio.
2105  */
folio_shift(struct folio * folio)2106 static inline unsigned int folio_shift(struct folio *folio)
2107 {
2108 	return PAGE_SHIFT + folio_order(folio);
2109 }
2110 
2111 /**
2112  * folio_size - The number of bytes in a folio.
2113  * @folio: The folio.
2114  *
2115  * Context: The caller should have a reference on the folio to prevent
2116  * it from being split.  It is not necessary for the folio to be locked.
2117  * Return: The number of bytes in this folio.
2118  */
folio_size(struct folio * folio)2119 static inline size_t folio_size(struct folio *folio)
2120 {
2121 	return PAGE_SIZE << folio_order(folio);
2122 }
2123 
2124 /**
2125  * folio_estimated_sharers - Estimate the number of sharers of a folio.
2126  * @folio: The folio.
2127  *
2128  * folio_estimated_sharers() aims to serve as a function to efficiently
2129  * estimate the number of processes sharing a folio. This is done by
2130  * looking at the precise mapcount of the first subpage in the folio, and
2131  * assuming the other subpages are the same. This may not be true for large
2132  * folios. If you want exact mapcounts for exact calculations, look at
2133  * page_mapcount() or folio_total_mapcount().
2134  *
2135  * Return: The estimated number of processes sharing a folio.
2136  */
folio_estimated_sharers(struct folio * folio)2137 static inline int folio_estimated_sharers(struct folio *folio)
2138 {
2139 	return page_mapcount(folio_page(folio, 0));
2140 }
2141 
2142 #ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE
arch_make_page_accessible(struct page * page)2143 static inline int arch_make_page_accessible(struct page *page)
2144 {
2145 	return 0;
2146 }
2147 #endif
2148 
2149 #ifndef HAVE_ARCH_MAKE_FOLIO_ACCESSIBLE
arch_make_folio_accessible(struct folio * folio)2150 static inline int arch_make_folio_accessible(struct folio *folio)
2151 {
2152 	int ret;
2153 	long i, nr = folio_nr_pages(folio);
2154 
2155 	for (i = 0; i < nr; i++) {
2156 		ret = arch_make_page_accessible(folio_page(folio, i));
2157 		if (ret)
2158 			break;
2159 	}
2160 
2161 	return ret;
2162 }
2163 #endif
2164 
2165 /*
2166  * Some inline functions in vmstat.h depend on page_zone()
2167  */
2168 #include <linux/vmstat.h>
2169 
lowmem_page_address(const struct page * page)2170 static __always_inline void *lowmem_page_address(const struct page *page)
2171 {
2172 	return page_to_virt(page);
2173 }
2174 
2175 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL)
2176 #define HASHED_PAGE_VIRTUAL
2177 #endif
2178 
2179 #if defined(WANT_PAGE_VIRTUAL)
page_address(const struct page * page)2180 static inline void *page_address(const struct page *page)
2181 {
2182 	return page->virtual;
2183 }
set_page_address(struct page * page,void * address)2184 static inline void set_page_address(struct page *page, void *address)
2185 {
2186 	page->virtual = address;
2187 }
2188 #define page_address_init()  do { } while(0)
2189 #endif
2190 
2191 #if defined(HASHED_PAGE_VIRTUAL)
2192 void *page_address(const struct page *page);
2193 void set_page_address(struct page *page, void *virtual);
2194 void page_address_init(void);
2195 #endif
2196 
2197 #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL)
2198 #define page_address(page) lowmem_page_address(page)
2199 #define set_page_address(page, address)  do { } while(0)
2200 #define page_address_init()  do { } while(0)
2201 #endif
2202 
folio_address(const struct folio * folio)2203 static inline void *folio_address(const struct folio *folio)
2204 {
2205 	return page_address(&folio->page);
2206 }
2207 
2208 extern pgoff_t __page_file_index(struct page *page);
2209 
2210 /*
2211  * Return the pagecache index of the passed page.  Regular pagecache pages
2212  * use ->index whereas swapcache pages use swp_offset(->private)
2213  */
page_index(struct page * page)2214 static inline pgoff_t page_index(struct page *page)
2215 {
2216 	if (unlikely(PageSwapCache(page)))
2217 		return __page_file_index(page);
2218 	return page->index;
2219 }
2220 
2221 /*
2222  * Return true only if the page has been allocated with
2223  * ALLOC_NO_WATERMARKS and the low watermark was not
2224  * met implying that the system is under some pressure.
2225  */
page_is_pfmemalloc(const struct page * page)2226 static inline bool page_is_pfmemalloc(const struct page *page)
2227 {
2228 	/*
2229 	 * lru.next has bit 1 set if the page is allocated from the
2230 	 * pfmemalloc reserves.  Callers may simply overwrite it if
2231 	 * they do not need to preserve that information.
2232 	 */
2233 	return (uintptr_t)page->lru.next & BIT(1);
2234 }
2235 
2236 /*
2237  * Return true only if the folio has been allocated with
2238  * ALLOC_NO_WATERMARKS and the low watermark was not
2239  * met implying that the system is under some pressure.
2240  */
folio_is_pfmemalloc(const struct folio * folio)2241 static inline bool folio_is_pfmemalloc(const struct folio *folio)
2242 {
2243 	/*
2244 	 * lru.next has bit 1 set if the page is allocated from the
2245 	 * pfmemalloc reserves.  Callers may simply overwrite it if
2246 	 * they do not need to preserve that information.
2247 	 */
2248 	return (uintptr_t)folio->lru.next & BIT(1);
2249 }
2250 
2251 /*
2252  * Only to be called by the page allocator on a freshly allocated
2253  * page.
2254  */
set_page_pfmemalloc(struct page * page)2255 static inline void set_page_pfmemalloc(struct page *page)
2256 {
2257 	page->lru.next = (void *)BIT(1);
2258 }
2259 
clear_page_pfmemalloc(struct page * page)2260 static inline void clear_page_pfmemalloc(struct page *page)
2261 {
2262 	page->lru.next = NULL;
2263 }
2264 
2265 /*
2266  * Can be called by the pagefault handler when it gets a VM_FAULT_OOM.
2267  */
2268 extern void pagefault_out_of_memory(void);
2269 
2270 #define offset_in_page(p)	((unsigned long)(p) & ~PAGE_MASK)
2271 #define offset_in_thp(page, p)	((unsigned long)(p) & (thp_size(page) - 1))
2272 #define offset_in_folio(folio, p) ((unsigned long)(p) & (folio_size(folio) - 1))
2273 
2274 /*
2275  * Parameter block passed down to zap_pte_range in exceptional cases.
2276  */
2277 struct zap_details {
2278 	struct folio *single_folio;	/* Locked folio to be unmapped */
2279 	bool even_cows;			/* Zap COWed private pages too? */
2280 	zap_flags_t zap_flags;		/* Extra flags for zapping */
2281 };
2282 
2283 /*
2284  * Whether to drop the pte markers, for example, the uffd-wp information for
2285  * file-backed memory.  This should only be specified when we will completely
2286  * drop the page in the mm, either by truncation or unmapping of the vma.  By
2287  * default, the flag is not set.
2288  */
2289 #define  ZAP_FLAG_DROP_MARKER        ((__force zap_flags_t) BIT(0))
2290 /* Set in unmap_vmas() to indicate a final unmap call.  Only used by hugetlb */
2291 #define  ZAP_FLAG_UNMAP              ((__force zap_flags_t) BIT(1))
2292 
2293 #ifdef CONFIG_SCHED_MM_CID
2294 void sched_mm_cid_before_execve(struct task_struct *t);
2295 void sched_mm_cid_after_execve(struct task_struct *t);
2296 void sched_mm_cid_fork(struct task_struct *t);
2297 void sched_mm_cid_exit_signals(struct task_struct *t);
task_mm_cid(struct task_struct * t)2298 static inline int task_mm_cid(struct task_struct *t)
2299 {
2300 	return t->mm_cid;
2301 }
2302 #else
sched_mm_cid_before_execve(struct task_struct * t)2303 static inline void sched_mm_cid_before_execve(struct task_struct *t) { }
sched_mm_cid_after_execve(struct task_struct * t)2304 static inline void sched_mm_cid_after_execve(struct task_struct *t) { }
sched_mm_cid_fork(struct task_struct * t)2305 static inline void sched_mm_cid_fork(struct task_struct *t) { }
sched_mm_cid_exit_signals(struct task_struct * t)2306 static inline void sched_mm_cid_exit_signals(struct task_struct *t) { }
task_mm_cid(struct task_struct * t)2307 static inline int task_mm_cid(struct task_struct *t)
2308 {
2309 	/*
2310 	 * Use the processor id as a fall-back when the mm cid feature is
2311 	 * disabled. This provides functional per-cpu data structure accesses
2312 	 * in user-space, althrough it won't provide the memory usage benefits.
2313 	 */
2314 	return raw_smp_processor_id();
2315 }
2316 #endif
2317 
2318 #ifdef CONFIG_MMU
2319 extern bool can_do_mlock(void);
2320 #else
can_do_mlock(void)2321 static inline bool can_do_mlock(void) { return false; }
2322 #endif
2323 extern int user_shm_lock(size_t, struct ucounts *);
2324 extern void user_shm_unlock(size_t, struct ucounts *);
2325 
2326 struct folio *vm_normal_folio(struct vm_area_struct *vma, unsigned long addr,
2327 			     pte_t pte);
2328 struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
2329 			     pte_t pte);
2330 struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
2331 				pmd_t pmd);
2332 
2333 void zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
2334 		  unsigned long size);
2335 void zap_page_range_single(struct vm_area_struct *vma, unsigned long address,
2336 			   unsigned long size, struct zap_details *details);
zap_vma_pages(struct vm_area_struct * vma)2337 static inline void zap_vma_pages(struct vm_area_struct *vma)
2338 {
2339 	zap_page_range_single(vma, vma->vm_start,
2340 			      vma->vm_end - vma->vm_start, NULL);
2341 }
2342 void unmap_vmas(struct mmu_gather *tlb, struct ma_state *mas,
2343 		struct vm_area_struct *start_vma, unsigned long start,
2344 		unsigned long end, unsigned long tree_end, bool mm_wr_locked);
2345 
2346 struct mmu_notifier_range;
2347 
2348 void free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
2349 		unsigned long end, unsigned long floor, unsigned long ceiling);
2350 int
2351 copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma);
2352 int follow_pte(struct mm_struct *mm, unsigned long address,
2353 	       pte_t **ptepp, spinlock_t **ptlp);
2354 int follow_pfn(struct vm_area_struct *vma, unsigned long address,
2355 	unsigned long *pfn);
2356 int follow_phys(struct vm_area_struct *vma, unsigned long address,
2357 		unsigned int flags, unsigned long *prot, resource_size_t *phys);
2358 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
2359 			void *buf, int len, int write);
2360 
2361 extern void truncate_pagecache(struct inode *inode, loff_t new);
2362 extern void truncate_setsize(struct inode *inode, loff_t newsize);
2363 void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);
2364 void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end);
2365 int generic_error_remove_page(struct address_space *mapping, struct page *page);
2366 
2367 struct vm_area_struct *lock_mm_and_find_vma(struct mm_struct *mm,
2368 		unsigned long address, struct pt_regs *regs);
2369 
2370 #ifdef CONFIG_MMU
2371 extern vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
2372 				  unsigned long address, unsigned int flags,
2373 				  struct pt_regs *regs);
2374 extern int fixup_user_fault(struct mm_struct *mm,
2375 			    unsigned long address, unsigned int fault_flags,
2376 			    bool *unlocked);
2377 void unmap_mapping_pages(struct address_space *mapping,
2378 		pgoff_t start, pgoff_t nr, bool even_cows);
2379 void unmap_mapping_range(struct address_space *mapping,
2380 		loff_t const holebegin, loff_t const holelen, int even_cows);
2381 #else
handle_mm_fault(struct vm_area_struct * vma,unsigned long address,unsigned int flags,struct pt_regs * regs)2382 static inline vm_fault_t handle_mm_fault(struct vm_area_struct *vma,
2383 					 unsigned long address, unsigned int flags,
2384 					 struct pt_regs *regs)
2385 {
2386 	/* should never happen if there's no MMU */
2387 	BUG();
2388 	return VM_FAULT_SIGBUS;
2389 }
fixup_user_fault(struct mm_struct * mm,unsigned long address,unsigned int fault_flags,bool * unlocked)2390 static inline int fixup_user_fault(struct mm_struct *mm, unsigned long address,
2391 		unsigned int fault_flags, bool *unlocked)
2392 {
2393 	/* should never happen if there's no MMU */
2394 	BUG();
2395 	return -EFAULT;
2396 }
unmap_mapping_pages(struct address_space * mapping,pgoff_t start,pgoff_t nr,bool even_cows)2397 static inline void unmap_mapping_pages(struct address_space *mapping,
2398 		pgoff_t start, pgoff_t nr, bool even_cows) { }
unmap_mapping_range(struct address_space * mapping,loff_t const holebegin,loff_t const holelen,int even_cows)2399 static inline void unmap_mapping_range(struct address_space *mapping,
2400 		loff_t const holebegin, loff_t const holelen, int even_cows) { }
2401 #endif
2402 
unmap_shared_mapping_range(struct address_space * mapping,loff_t const holebegin,loff_t const holelen)2403 static inline void unmap_shared_mapping_range(struct address_space *mapping,
2404 		loff_t const holebegin, loff_t const holelen)
2405 {
2406 	unmap_mapping_range(mapping, holebegin, holelen, 0);
2407 }
2408 
2409 static inline struct vm_area_struct *vma_lookup(struct mm_struct *mm,
2410 						unsigned long addr);
2411 
2412 extern int access_process_vm(struct task_struct *tsk, unsigned long addr,
2413 		void *buf, int len, unsigned int gup_flags);
2414 extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
2415 		void *buf, int len, unsigned int gup_flags);
2416 extern int __access_remote_vm(struct mm_struct *mm, unsigned long addr,
2417 			      void *buf, int len, unsigned int gup_flags);
2418 
2419 long get_user_pages_remote(struct mm_struct *mm,
2420 			   unsigned long start, unsigned long nr_pages,
2421 			   unsigned int gup_flags, struct page **pages,
2422 			   int *locked);
2423 long pin_user_pages_remote(struct mm_struct *mm,
2424 			   unsigned long start, unsigned long nr_pages,
2425 			   unsigned int gup_flags, struct page **pages,
2426 			   int *locked);
2427 
get_user_page_vma_remote(struct mm_struct * mm,unsigned long addr,int gup_flags,struct vm_area_struct ** vmap)2428 static inline struct page *get_user_page_vma_remote(struct mm_struct *mm,
2429 						    unsigned long addr,
2430 						    int gup_flags,
2431 						    struct vm_area_struct **vmap)
2432 {
2433 	struct page *page;
2434 	struct vm_area_struct *vma;
2435 	int got = get_user_pages_remote(mm, addr, 1, gup_flags, &page, NULL);
2436 
2437 	if (got < 0)
2438 		return ERR_PTR(got);
2439 	if (got == 0)
2440 		return NULL;
2441 
2442 	vma = vma_lookup(mm, addr);
2443 	if (WARN_ON_ONCE(!vma)) {
2444 		put_page(page);
2445 		return ERR_PTR(-EINVAL);
2446 	}
2447 
2448 	*vmap = vma;
2449 	return page;
2450 }
2451 
2452 long get_user_pages(unsigned long start, unsigned long nr_pages,
2453 		    unsigned int gup_flags, struct page **pages);
2454 long pin_user_pages(unsigned long start, unsigned long nr_pages,
2455 		    unsigned int gup_flags, struct page **pages);
2456 long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
2457 		    struct page **pages, unsigned int gup_flags);
2458 long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
2459 		    struct page **pages, unsigned int gup_flags);
2460 
2461 int get_user_pages_fast(unsigned long start, int nr_pages,
2462 			unsigned int gup_flags, struct page **pages);
2463 int pin_user_pages_fast(unsigned long start, int nr_pages,
2464 			unsigned int gup_flags, struct page **pages);
2465 void folio_add_pin(struct folio *folio);
2466 
2467 int account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc);
2468 int __account_locked_vm(struct mm_struct *mm, unsigned long pages, bool inc,
2469 			struct task_struct *task, bool bypass_rlim);
2470 
2471 struct kvec;
2472 struct page *get_dump_page(unsigned long addr);
2473 
2474 bool folio_mark_dirty(struct folio *folio);
2475 bool set_page_dirty(struct page *page);
2476 int set_page_dirty_lock(struct page *page);
2477 
2478 int get_cmdline(struct task_struct *task, char *buffer, int buflen);
2479 
2480 extern unsigned long move_page_tables(struct vm_area_struct *vma,
2481 		unsigned long old_addr, struct vm_area_struct *new_vma,
2482 		unsigned long new_addr, unsigned long len,
2483 		bool need_rmap_locks);
2484 
2485 /*
2486  * Flags used by change_protection().  For now we make it a bitmap so
2487  * that we can pass in multiple flags just like parameters.  However
2488  * for now all the callers are only use one of the flags at the same
2489  * time.
2490  */
2491 /*
2492  * Whether we should manually check if we can map individual PTEs writable,
2493  * because something (e.g., COW, uffd-wp) blocks that from happening for all
2494  * PTEs automatically in a writable mapping.
2495  */
2496 #define  MM_CP_TRY_CHANGE_WRITABLE	   (1UL << 0)
2497 /* Whether this protection change is for NUMA hints */
2498 #define  MM_CP_PROT_NUMA                   (1UL << 1)
2499 /* Whether this change is for write protecting */
2500 #define  MM_CP_UFFD_WP                     (1UL << 2) /* do wp */
2501 #define  MM_CP_UFFD_WP_RESOLVE             (1UL << 3) /* Resolve wp */
2502 #define  MM_CP_UFFD_WP_ALL                 (MM_CP_UFFD_WP | \
2503 					    MM_CP_UFFD_WP_RESOLVE)
2504 
2505 bool vma_needs_dirty_tracking(struct vm_area_struct *vma);
2506 int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot);
vma_wants_manual_pte_write_upgrade(struct vm_area_struct * vma)2507 static inline bool vma_wants_manual_pte_write_upgrade(struct vm_area_struct *vma)
2508 {
2509 	/*
2510 	 * We want to check manually if we can change individual PTEs writable
2511 	 * if we can't do that automatically for all PTEs in a mapping. For
2512 	 * private mappings, that's always the case when we have write
2513 	 * permissions as we properly have to handle COW.
2514 	 */
2515 	if (vma->vm_flags & VM_SHARED)
2516 		return vma_wants_writenotify(vma, vma->vm_page_prot);
2517 	return !!(vma->vm_flags & VM_WRITE);
2518 
2519 }
2520 bool can_change_pte_writable(struct vm_area_struct *vma, unsigned long addr,
2521 			     pte_t pte);
2522 extern long change_protection(struct mmu_gather *tlb,
2523 			      struct vm_area_struct *vma, unsigned long start,
2524 			      unsigned long end, unsigned long cp_flags);
2525 extern int mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb,
2526 	  struct vm_area_struct *vma, struct vm_area_struct **pprev,
2527 	  unsigned long start, unsigned long end, unsigned long newflags);
2528 
2529 /*
2530  * doesn't attempt to fault and will return short.
2531  */
2532 int get_user_pages_fast_only(unsigned long start, int nr_pages,
2533 			     unsigned int gup_flags, struct page **pages);
2534 
get_user_page_fast_only(unsigned long addr,unsigned int gup_flags,struct page ** pagep)2535 static inline bool get_user_page_fast_only(unsigned long addr,
2536 			unsigned int gup_flags, struct page **pagep)
2537 {
2538 	return get_user_pages_fast_only(addr, 1, gup_flags, pagep) == 1;
2539 }
2540 /*
2541  * per-process(per-mm_struct) statistics.
2542  */
get_mm_counter(struct mm_struct * mm,int member)2543 static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
2544 {
2545 	return percpu_counter_read_positive(&mm->rss_stat[member]);
2546 }
2547 
2548 void mm_trace_rss_stat(struct mm_struct *mm, int member);
2549 
add_mm_counter(struct mm_struct * mm,int member,long value)2550 static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
2551 {
2552 	percpu_counter_add(&mm->rss_stat[member], value);
2553 
2554 	mm_trace_rss_stat(mm, member);
2555 }
2556 
inc_mm_counter(struct mm_struct * mm,int member)2557 static inline void inc_mm_counter(struct mm_struct *mm, int member)
2558 {
2559 	percpu_counter_inc(&mm->rss_stat[member]);
2560 
2561 	mm_trace_rss_stat(mm, member);
2562 }
2563 
dec_mm_counter(struct mm_struct * mm,int member)2564 static inline void dec_mm_counter(struct mm_struct *mm, int member)
2565 {
2566 	percpu_counter_dec(&mm->rss_stat[member]);
2567 
2568 	mm_trace_rss_stat(mm, member);
2569 }
2570 
2571 /* Optimized variant when page is already known not to be PageAnon */
mm_counter_file(struct page * page)2572 static inline int mm_counter_file(struct page *page)
2573 {
2574 	if (PageSwapBacked(page))
2575 		return MM_SHMEMPAGES;
2576 	return MM_FILEPAGES;
2577 }
2578 
mm_counter(struct page * page)2579 static inline int mm_counter(struct page *page)
2580 {
2581 	if (PageAnon(page))
2582 		return MM_ANONPAGES;
2583 	return mm_counter_file(page);
2584 }
2585 
get_mm_rss(struct mm_struct * mm)2586 static inline unsigned long get_mm_rss(struct mm_struct *mm)
2587 {
2588 	return get_mm_counter(mm, MM_FILEPAGES) +
2589 		get_mm_counter(mm, MM_ANONPAGES) +
2590 		get_mm_counter(mm, MM_SHMEMPAGES);
2591 }
2592 
get_mm_hiwater_rss(struct mm_struct * mm)2593 static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
2594 {
2595 	return max(mm->hiwater_rss, get_mm_rss(mm));
2596 }
2597 
get_mm_hiwater_vm(struct mm_struct * mm)2598 static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
2599 {
2600 	return max(mm->hiwater_vm, mm->total_vm);
2601 }
2602 
update_hiwater_rss(struct mm_struct * mm)2603 static inline void update_hiwater_rss(struct mm_struct *mm)
2604 {
2605 	unsigned long _rss = get_mm_rss(mm);
2606 
2607 	if ((mm)->hiwater_rss < _rss)
2608 		(mm)->hiwater_rss = _rss;
2609 }
2610 
update_hiwater_vm(struct mm_struct * mm)2611 static inline void update_hiwater_vm(struct mm_struct *mm)
2612 {
2613 	if (mm->hiwater_vm < mm->total_vm)
2614 		mm->hiwater_vm = mm->total_vm;
2615 }
2616 
reset_mm_hiwater_rss(struct mm_struct * mm)2617 static inline void reset_mm_hiwater_rss(struct mm_struct *mm)
2618 {
2619 	mm->hiwater_rss = get_mm_rss(mm);
2620 }
2621 
setmax_mm_hiwater_rss(unsigned long * maxrss,struct mm_struct * mm)2622 static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
2623 					 struct mm_struct *mm)
2624 {
2625 	unsigned long hiwater_rss = get_mm_hiwater_rss(mm);
2626 
2627 	if (*maxrss < hiwater_rss)
2628 		*maxrss = hiwater_rss;
2629 }
2630 
2631 #if defined(SPLIT_RSS_COUNTING)
2632 void sync_mm_rss(struct mm_struct *mm);
2633 #else
sync_mm_rss(struct mm_struct * mm)2634 static inline void sync_mm_rss(struct mm_struct *mm)
2635 {
2636 }
2637 #endif
2638 
2639 #ifndef CONFIG_ARCH_HAS_PTE_SPECIAL
pte_special(pte_t pte)2640 static inline int pte_special(pte_t pte)
2641 {
2642 	return 0;
2643 }
2644 
pte_mkspecial(pte_t pte)2645 static inline pte_t pte_mkspecial(pte_t pte)
2646 {
2647 	return pte;
2648 }
2649 #endif
2650 
2651 #ifndef CONFIG_ARCH_HAS_PTE_DEVMAP
pte_devmap(pte_t pte)2652 static inline int pte_devmap(pte_t pte)
2653 {
2654 	return 0;
2655 }
2656 #endif
2657 
2658 extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr,
2659 			       spinlock_t **ptl);
get_locked_pte(struct mm_struct * mm,unsigned long addr,spinlock_t ** ptl)2660 static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr,
2661 				    spinlock_t **ptl)
2662 {
2663 	pte_t *ptep;
2664 	__cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl));
2665 	return ptep;
2666 }
2667 
2668 #ifdef __PAGETABLE_P4D_FOLDED
__p4d_alloc(struct mm_struct * mm,pgd_t * pgd,unsigned long address)2669 static inline int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
2670 						unsigned long address)
2671 {
2672 	return 0;
2673 }
2674 #else
2675 int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address);
2676 #endif
2677 
2678 #if defined(__PAGETABLE_PUD_FOLDED) || !defined(CONFIG_MMU)
__pud_alloc(struct mm_struct * mm,p4d_t * p4d,unsigned long address)2679 static inline int __pud_alloc(struct mm_struct *mm, p4d_t *p4d,
2680 						unsigned long address)
2681 {
2682 	return 0;
2683 }
mm_inc_nr_puds(struct mm_struct * mm)2684 static inline void mm_inc_nr_puds(struct mm_struct *mm) {}
mm_dec_nr_puds(struct mm_struct * mm)2685 static inline void mm_dec_nr_puds(struct mm_struct *mm) {}
2686 
2687 #else
2688 int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address);
2689 
mm_inc_nr_puds(struct mm_struct * mm)2690 static inline void mm_inc_nr_puds(struct mm_struct *mm)
2691 {
2692 	if (mm_pud_folded(mm))
2693 		return;
2694 	atomic_long_add(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
2695 }
2696 
mm_dec_nr_puds(struct mm_struct * mm)2697 static inline void mm_dec_nr_puds(struct mm_struct *mm)
2698 {
2699 	if (mm_pud_folded(mm))
2700 		return;
2701 	atomic_long_sub(PTRS_PER_PUD * sizeof(pud_t), &mm->pgtables_bytes);
2702 }
2703 #endif
2704 
2705 #if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU)
__pmd_alloc(struct mm_struct * mm,pud_t * pud,unsigned long address)2706 static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud,
2707 						unsigned long address)
2708 {
2709 	return 0;
2710 }
2711 
mm_inc_nr_pmds(struct mm_struct * mm)2712 static inline void mm_inc_nr_pmds(struct mm_struct *mm) {}
mm_dec_nr_pmds(struct mm_struct * mm)2713 static inline void mm_dec_nr_pmds(struct mm_struct *mm) {}
2714 
2715 #else
2716 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address);
2717 
mm_inc_nr_pmds(struct mm_struct * mm)2718 static inline void mm_inc_nr_pmds(struct mm_struct *mm)
2719 {
2720 	if (mm_pmd_folded(mm))
2721 		return;
2722 	atomic_long_add(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2723 }
2724 
mm_dec_nr_pmds(struct mm_struct * mm)2725 static inline void mm_dec_nr_pmds(struct mm_struct *mm)
2726 {
2727 	if (mm_pmd_folded(mm))
2728 		return;
2729 	atomic_long_sub(PTRS_PER_PMD * sizeof(pmd_t), &mm->pgtables_bytes);
2730 }
2731 #endif
2732 
2733 #ifdef CONFIG_MMU
mm_pgtables_bytes_init(struct mm_struct * mm)2734 static inline void mm_pgtables_bytes_init(struct mm_struct *mm)
2735 {
2736 	atomic_long_set(&mm->pgtables_bytes, 0);
2737 }
2738 
mm_pgtables_bytes(const struct mm_struct * mm)2739 static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2740 {
2741 	return atomic_long_read(&mm->pgtables_bytes);
2742 }
2743 
mm_inc_nr_ptes(struct mm_struct * mm)2744 static inline void mm_inc_nr_ptes(struct mm_struct *mm)
2745 {
2746 	atomic_long_add(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2747 }
2748 
mm_dec_nr_ptes(struct mm_struct * mm)2749 static inline void mm_dec_nr_ptes(struct mm_struct *mm)
2750 {
2751 	atomic_long_sub(PTRS_PER_PTE * sizeof(pte_t), &mm->pgtables_bytes);
2752 }
2753 #else
2754 
mm_pgtables_bytes_init(struct mm_struct * mm)2755 static inline void mm_pgtables_bytes_init(struct mm_struct *mm) {}
mm_pgtables_bytes(const struct mm_struct * mm)2756 static inline unsigned long mm_pgtables_bytes(const struct mm_struct *mm)
2757 {
2758 	return 0;
2759 }
2760 
mm_inc_nr_ptes(struct mm_struct * mm)2761 static inline void mm_inc_nr_ptes(struct mm_struct *mm) {}
mm_dec_nr_ptes(struct mm_struct * mm)2762 static inline void mm_dec_nr_ptes(struct mm_struct *mm) {}
2763 #endif
2764 
2765 int __pte_alloc(struct mm_struct *mm, pmd_t *pmd);
2766 int __pte_alloc_kernel(pmd_t *pmd);
2767 
2768 #if defined(CONFIG_MMU)
2769 
p4d_alloc(struct mm_struct * mm,pgd_t * pgd,unsigned long address)2770 static inline p4d_t *p4d_alloc(struct mm_struct *mm, pgd_t *pgd,
2771 		unsigned long address)
2772 {
2773 	return (unlikely(pgd_none(*pgd)) && __p4d_alloc(mm, pgd, address)) ?
2774 		NULL : p4d_offset(pgd, address);
2775 }
2776 
pud_alloc(struct mm_struct * mm,p4d_t * p4d,unsigned long address)2777 static inline pud_t *pud_alloc(struct mm_struct *mm, p4d_t *p4d,
2778 		unsigned long address)
2779 {
2780 	return (unlikely(p4d_none(*p4d)) && __pud_alloc(mm, p4d, address)) ?
2781 		NULL : pud_offset(p4d, address);
2782 }
2783 
pmd_alloc(struct mm_struct * mm,pud_t * pud,unsigned long address)2784 static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
2785 {
2786 	return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))?
2787 		NULL: pmd_offset(pud, address);
2788 }
2789 #endif /* CONFIG_MMU */
2790 
virt_to_ptdesc(const void * x)2791 static inline struct ptdesc *virt_to_ptdesc(const void *x)
2792 {
2793 	return page_ptdesc(virt_to_page(x));
2794 }
2795 
ptdesc_to_virt(const struct ptdesc * pt)2796 static inline void *ptdesc_to_virt(const struct ptdesc *pt)
2797 {
2798 	return page_to_virt(ptdesc_page(pt));
2799 }
2800 
ptdesc_address(const struct ptdesc * pt)2801 static inline void *ptdesc_address(const struct ptdesc *pt)
2802 {
2803 	return folio_address(ptdesc_folio(pt));
2804 }
2805 
pagetable_is_reserved(struct ptdesc * pt)2806 static inline bool pagetable_is_reserved(struct ptdesc *pt)
2807 {
2808 	return folio_test_reserved(ptdesc_folio(pt));
2809 }
2810 
2811 /**
2812  * pagetable_alloc - Allocate pagetables
2813  * @gfp:    GFP flags
2814  * @order:  desired pagetable order
2815  *
2816  * pagetable_alloc allocates memory for page tables as well as a page table
2817  * descriptor to describe that memory.
2818  *
2819  * Return: The ptdesc describing the allocated page tables.
2820  */
pagetable_alloc(gfp_t gfp,unsigned int order)2821 static inline struct ptdesc *pagetable_alloc(gfp_t gfp, unsigned int order)
2822 {
2823 	struct page *page = alloc_pages(gfp | __GFP_COMP, order);
2824 
2825 	return page_ptdesc(page);
2826 }
2827 
2828 /**
2829  * pagetable_free - Free pagetables
2830  * @pt:	The page table descriptor
2831  *
2832  * pagetable_free frees the memory of all page tables described by a page
2833  * table descriptor and the memory for the descriptor itself.
2834  */
pagetable_free(struct ptdesc * pt)2835 static inline void pagetable_free(struct ptdesc *pt)
2836 {
2837 	struct page *page = ptdesc_page(pt);
2838 
2839 	__free_pages(page, compound_order(page));
2840 }
2841 
2842 #if USE_SPLIT_PTE_PTLOCKS
2843 #if ALLOC_SPLIT_PTLOCKS
2844 void __init ptlock_cache_init(void);
2845 bool ptlock_alloc(struct ptdesc *ptdesc);
2846 void ptlock_free(struct ptdesc *ptdesc);
2847 
ptlock_ptr(struct ptdesc * ptdesc)2848 static inline spinlock_t *ptlock_ptr(struct ptdesc *ptdesc)
2849 {
2850 	return ptdesc->ptl;
2851 }
2852 #else /* ALLOC_SPLIT_PTLOCKS */
ptlock_cache_init(void)2853 static inline void ptlock_cache_init(void)
2854 {
2855 }
2856 
ptlock_alloc(struct ptdesc * ptdesc)2857 static inline bool ptlock_alloc(struct ptdesc *ptdesc)
2858 {
2859 	return true;
2860 }
2861 
ptlock_free(struct ptdesc * ptdesc)2862 static inline void ptlock_free(struct ptdesc *ptdesc)
2863 {
2864 }
2865 
ptlock_ptr(struct ptdesc * ptdesc)2866 static inline spinlock_t *ptlock_ptr(struct ptdesc *ptdesc)
2867 {
2868 	return &ptdesc->ptl;
2869 }
2870 #endif /* ALLOC_SPLIT_PTLOCKS */
2871 
pte_lockptr(struct mm_struct * mm,pmd_t * pmd)2872 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2873 {
2874 	return ptlock_ptr(page_ptdesc(pmd_page(*pmd)));
2875 }
2876 
ptlock_init(struct ptdesc * ptdesc)2877 static inline bool ptlock_init(struct ptdesc *ptdesc)
2878 {
2879 	/*
2880 	 * prep_new_page() initialize page->private (and therefore page->ptl)
2881 	 * with 0. Make sure nobody took it in use in between.
2882 	 *
2883 	 * It can happen if arch try to use slab for page table allocation:
2884 	 * slab code uses page->slab_cache, which share storage with page->ptl.
2885 	 */
2886 	VM_BUG_ON_PAGE(*(unsigned long *)&ptdesc->ptl, ptdesc_page(ptdesc));
2887 	if (!ptlock_alloc(ptdesc))
2888 		return false;
2889 	spin_lock_init(ptlock_ptr(ptdesc));
2890 	return true;
2891 }
2892 
2893 #else	/* !USE_SPLIT_PTE_PTLOCKS */
2894 /*
2895  * We use mm->page_table_lock to guard all pagetable pages of the mm.
2896  */
pte_lockptr(struct mm_struct * mm,pmd_t * pmd)2897 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
2898 {
2899 	return &mm->page_table_lock;
2900 }
ptlock_cache_init(void)2901 static inline void ptlock_cache_init(void) {}
ptlock_init(struct ptdesc * ptdesc)2902 static inline bool ptlock_init(struct ptdesc *ptdesc) { return true; }
ptlock_free(struct ptdesc * ptdesc)2903 static inline void ptlock_free(struct ptdesc *ptdesc) {}
2904 #endif /* USE_SPLIT_PTE_PTLOCKS */
2905 
pagetable_pte_ctor(struct ptdesc * ptdesc)2906 static inline bool pagetable_pte_ctor(struct ptdesc *ptdesc)
2907 {
2908 	struct folio *folio = ptdesc_folio(ptdesc);
2909 
2910 	if (!ptlock_init(ptdesc))
2911 		return false;
2912 	__folio_set_pgtable(folio);
2913 	lruvec_stat_add_folio(folio, NR_PAGETABLE);
2914 	return true;
2915 }
2916 
pagetable_pte_dtor(struct ptdesc * ptdesc)2917 static inline void pagetable_pte_dtor(struct ptdesc *ptdesc)
2918 {
2919 	struct folio *folio = ptdesc_folio(ptdesc);
2920 
2921 	ptlock_free(ptdesc);
2922 	__folio_clear_pgtable(folio);
2923 	lruvec_stat_sub_folio(folio, NR_PAGETABLE);
2924 }
2925 
2926 pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp);
pte_offset_map(pmd_t * pmd,unsigned long addr)2927 static inline pte_t *pte_offset_map(pmd_t *pmd, unsigned long addr)
2928 {
2929 	return __pte_offset_map(pmd, addr, NULL);
2930 }
2931 
2932 pte_t *__pte_offset_map_lock(struct mm_struct *mm, pmd_t *pmd,
2933 			unsigned long addr, spinlock_t **ptlp);
pte_offset_map_lock(struct mm_struct * mm,pmd_t * pmd,unsigned long addr,spinlock_t ** ptlp)2934 static inline pte_t *pte_offset_map_lock(struct mm_struct *mm, pmd_t *pmd,
2935 			unsigned long addr, spinlock_t **ptlp)
2936 {
2937 	pte_t *pte;
2938 
2939 	__cond_lock(*ptlp, pte = __pte_offset_map_lock(mm, pmd, addr, ptlp));
2940 	return pte;
2941 }
2942 
2943 pte_t *pte_offset_map_nolock(struct mm_struct *mm, pmd_t *pmd,
2944 			unsigned long addr, spinlock_t **ptlp);
2945 
2946 #define pte_unmap_unlock(pte, ptl)	do {		\
2947 	spin_unlock(ptl);				\
2948 	pte_unmap(pte);					\
2949 } while (0)
2950 
2951 #define pte_alloc(mm, pmd) (unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, pmd))
2952 
2953 #define pte_alloc_map(mm, pmd, address)			\
2954 	(pte_alloc(mm, pmd) ? NULL : pte_offset_map(pmd, address))
2955 
2956 #define pte_alloc_map_lock(mm, pmd, address, ptlp)	\
2957 	(pte_alloc(mm, pmd) ?			\
2958 		 NULL : pte_offset_map_lock(mm, pmd, address, ptlp))
2959 
2960 #define pte_alloc_kernel(pmd, address)			\
2961 	((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \
2962 		NULL: pte_offset_kernel(pmd, address))
2963 
2964 #if USE_SPLIT_PMD_PTLOCKS
2965 
pmd_pgtable_page(pmd_t * pmd)2966 static inline struct page *pmd_pgtable_page(pmd_t *pmd)
2967 {
2968 	unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
2969 	return virt_to_page((void *)((unsigned long) pmd & mask));
2970 }
2971 
pmd_ptdesc(pmd_t * pmd)2972 static inline struct ptdesc *pmd_ptdesc(pmd_t *pmd)
2973 {
2974 	return page_ptdesc(pmd_pgtable_page(pmd));
2975 }
2976 
pmd_lockptr(struct mm_struct * mm,pmd_t * pmd)2977 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
2978 {
2979 	return ptlock_ptr(pmd_ptdesc(pmd));
2980 }
2981 
pmd_ptlock_init(struct ptdesc * ptdesc)2982 static inline bool pmd_ptlock_init(struct ptdesc *ptdesc)
2983 {
2984 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2985 	ptdesc->pmd_huge_pte = NULL;
2986 #endif
2987 	return ptlock_init(ptdesc);
2988 }
2989 
pmd_ptlock_free(struct ptdesc * ptdesc)2990 static inline void pmd_ptlock_free(struct ptdesc *ptdesc)
2991 {
2992 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
2993 	VM_BUG_ON_PAGE(ptdesc->pmd_huge_pte, ptdesc_page(ptdesc));
2994 #endif
2995 	ptlock_free(ptdesc);
2996 }
2997 
2998 #define pmd_huge_pte(mm, pmd) (pmd_ptdesc(pmd)->pmd_huge_pte)
2999 
3000 #else
3001 
pmd_lockptr(struct mm_struct * mm,pmd_t * pmd)3002 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd)
3003 {
3004 	return &mm->page_table_lock;
3005 }
3006 
pmd_ptlock_init(struct ptdesc * ptdesc)3007 static inline bool pmd_ptlock_init(struct ptdesc *ptdesc) { return true; }
pmd_ptlock_free(struct ptdesc * ptdesc)3008 static inline void pmd_ptlock_free(struct ptdesc *ptdesc) {}
3009 
3010 #define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte)
3011 
3012 #endif
3013 
pmd_lock(struct mm_struct * mm,pmd_t * pmd)3014 static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd)
3015 {
3016 	spinlock_t *ptl = pmd_lockptr(mm, pmd);
3017 	spin_lock(ptl);
3018 	return ptl;
3019 }
3020 
pagetable_pmd_ctor(struct ptdesc * ptdesc)3021 static inline bool pagetable_pmd_ctor(struct ptdesc *ptdesc)
3022 {
3023 	struct folio *folio = ptdesc_folio(ptdesc);
3024 
3025 	if (!pmd_ptlock_init(ptdesc))
3026 		return false;
3027 	__folio_set_pgtable(folio);
3028 	lruvec_stat_add_folio(folio, NR_PAGETABLE);
3029 	return true;
3030 }
3031 
pagetable_pmd_dtor(struct ptdesc * ptdesc)3032 static inline void pagetable_pmd_dtor(struct ptdesc *ptdesc)
3033 {
3034 	struct folio *folio = ptdesc_folio(ptdesc);
3035 
3036 	pmd_ptlock_free(ptdesc);
3037 	__folio_clear_pgtable(folio);
3038 	lruvec_stat_sub_folio(folio, NR_PAGETABLE);
3039 }
3040 
3041 /*
3042  * No scalability reason to split PUD locks yet, but follow the same pattern
3043  * as the PMD locks to make it easier if we decide to.  The VM should not be
3044  * considered ready to switch to split PUD locks yet; there may be places
3045  * which need to be converted from page_table_lock.
3046  */
pud_lockptr(struct mm_struct * mm,pud_t * pud)3047 static inline spinlock_t *pud_lockptr(struct mm_struct *mm, pud_t *pud)
3048 {
3049 	return &mm->page_table_lock;
3050 }
3051 
pud_lock(struct mm_struct * mm,pud_t * pud)3052 static inline spinlock_t *pud_lock(struct mm_struct *mm, pud_t *pud)
3053 {
3054 	spinlock_t *ptl = pud_lockptr(mm, pud);
3055 
3056 	spin_lock(ptl);
3057 	return ptl;
3058 }
3059 
3060 extern void __init pagecache_init(void);
3061 extern void free_initmem(void);
3062 
3063 /*
3064  * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK)
3065  * into the buddy system. The freed pages will be poisoned with pattern
3066  * "poison" if it's within range [0, UCHAR_MAX].
3067  * Return pages freed into the buddy system.
3068  */
3069 extern unsigned long free_reserved_area(void *start, void *end,
3070 					int poison, const char *s);
3071 
3072 extern void adjust_managed_page_count(struct page *page, long count);
3073 
3074 extern void reserve_bootmem_region(phys_addr_t start,
3075 				   phys_addr_t end, int nid);
3076 
3077 /* Free the reserved page into the buddy system, so it gets managed. */
free_reserved_page(struct page * page)3078 static inline void free_reserved_page(struct page *page)
3079 {
3080 	ClearPageReserved(page);
3081 	init_page_count(page);
3082 	__free_page(page);
3083 	adjust_managed_page_count(page, 1);
3084 }
3085 #define free_highmem_page(page) free_reserved_page(page)
3086 
mark_page_reserved(struct page * page)3087 static inline void mark_page_reserved(struct page *page)
3088 {
3089 	SetPageReserved(page);
3090 	adjust_managed_page_count(page, -1);
3091 }
3092 
free_reserved_ptdesc(struct ptdesc * pt)3093 static inline void free_reserved_ptdesc(struct ptdesc *pt)
3094 {
3095 	free_reserved_page(ptdesc_page(pt));
3096 }
3097 
3098 /*
3099  * Default method to free all the __init memory into the buddy system.
3100  * The freed pages will be poisoned with pattern "poison" if it's within
3101  * range [0, UCHAR_MAX].
3102  * Return pages freed into the buddy system.
3103  */
free_initmem_default(int poison)3104 static inline unsigned long free_initmem_default(int poison)
3105 {
3106 	extern char __init_begin[], __init_end[];
3107 
3108 	return free_reserved_area(&__init_begin, &__init_end,
3109 				  poison, "unused kernel image (initmem)");
3110 }
3111 
get_num_physpages(void)3112 static inline unsigned long get_num_physpages(void)
3113 {
3114 	int nid;
3115 	unsigned long phys_pages = 0;
3116 
3117 	for_each_online_node(nid)
3118 		phys_pages += node_present_pages(nid);
3119 
3120 	return phys_pages;
3121 }
3122 
3123 /*
3124  * Using memblock node mappings, an architecture may initialise its
3125  * zones, allocate the backing mem_map and account for memory holes in an
3126  * architecture independent manner.
3127  *
3128  * An architecture is expected to register range of page frames backed by
3129  * physical memory with memblock_add[_node]() before calling
3130  * free_area_init() passing in the PFN each zone ends at. At a basic
3131  * usage, an architecture is expected to do something like
3132  *
3133  * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn,
3134  * 							 max_highmem_pfn};
3135  * for_each_valid_physical_page_range()
3136  *	memblock_add_node(base, size, nid, MEMBLOCK_NONE)
3137  * free_area_init(max_zone_pfns);
3138  */
3139 void free_area_init(unsigned long *max_zone_pfn);
3140 unsigned long node_map_pfn_alignment(void);
3141 unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn,
3142 						unsigned long end_pfn);
3143 extern unsigned long absent_pages_in_range(unsigned long start_pfn,
3144 						unsigned long end_pfn);
3145 extern void get_pfn_range_for_nid(unsigned int nid,
3146 			unsigned long *start_pfn, unsigned long *end_pfn);
3147 
3148 #ifndef CONFIG_NUMA
early_pfn_to_nid(unsigned long pfn)3149 static inline int early_pfn_to_nid(unsigned long pfn)
3150 {
3151 	return 0;
3152 }
3153 #else
3154 /* please see mm/page_alloc.c */
3155 extern int __meminit early_pfn_to_nid(unsigned long pfn);
3156 #endif
3157 
3158 extern void set_dma_reserve(unsigned long new_dma_reserve);
3159 extern void mem_init(void);
3160 extern void __init mmap_init(void);
3161 
3162 extern void __show_mem(unsigned int flags, nodemask_t *nodemask, int max_zone_idx);
show_mem(void)3163 static inline void show_mem(void)
3164 {
3165 	__show_mem(0, NULL, MAX_NR_ZONES - 1);
3166 }
3167 extern long si_mem_available(void);
3168 extern void si_meminfo(struct sysinfo * val);
3169 extern void si_meminfo_node(struct sysinfo *val, int nid);
3170 #ifdef __HAVE_ARCH_RESERVED_KERNEL_PAGES
3171 extern unsigned long arch_reserved_kernel_pages(void);
3172 #endif
3173 
3174 extern __printf(3, 4)
3175 void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...);
3176 
3177 extern void setup_per_cpu_pageset(void);
3178 
3179 /* nommu.c */
3180 extern atomic_long_t mmap_pages_allocated;
3181 extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);
3182 
3183 /* interval_tree.c */
3184 void vma_interval_tree_insert(struct vm_area_struct *node,
3185 			      struct rb_root_cached *root);
3186 void vma_interval_tree_insert_after(struct vm_area_struct *node,
3187 				    struct vm_area_struct *prev,
3188 				    struct rb_root_cached *root);
3189 void vma_interval_tree_remove(struct vm_area_struct *node,
3190 			      struct rb_root_cached *root);
3191 struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root_cached *root,
3192 				unsigned long start, unsigned long last);
3193 struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node,
3194 				unsigned long start, unsigned long last);
3195 
3196 #define vma_interval_tree_foreach(vma, root, start, last)		\
3197 	for (vma = vma_interval_tree_iter_first(root, start, last);	\
3198 	     vma; vma = vma_interval_tree_iter_next(vma, start, last))
3199 
3200 void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
3201 				   struct rb_root_cached *root);
3202 void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
3203 				   struct rb_root_cached *root);
3204 struct anon_vma_chain *
3205 anon_vma_interval_tree_iter_first(struct rb_root_cached *root,
3206 				  unsigned long start, unsigned long last);
3207 struct anon_vma_chain *anon_vma_interval_tree_iter_next(
3208 	struct anon_vma_chain *node, unsigned long start, unsigned long last);
3209 #ifdef CONFIG_DEBUG_VM_RB
3210 void anon_vma_interval_tree_verify(struct anon_vma_chain *node);
3211 #endif
3212 
3213 #define anon_vma_interval_tree_foreach(avc, root, start, last)		 \
3214 	for (avc = anon_vma_interval_tree_iter_first(root, start, last); \
3215 	     avc; avc = anon_vma_interval_tree_iter_next(avc, start, last))
3216 
3217 /* mmap.c */
3218 extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin);
3219 extern int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma,
3220 		      unsigned long start, unsigned long end, pgoff_t pgoff,
3221 		      struct vm_area_struct *next);
3222 extern int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma,
3223 		       unsigned long start, unsigned long end, pgoff_t pgoff);
3224 extern struct vm_area_struct *vma_merge(struct vma_iterator *vmi,
3225 	struct mm_struct *, struct vm_area_struct *prev, unsigned long addr,
3226 	unsigned long end, unsigned long vm_flags, struct anon_vma *,
3227 	struct file *, pgoff_t, struct mempolicy *, struct vm_userfaultfd_ctx,
3228 	struct anon_vma_name *);
3229 extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *);
3230 extern int __split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
3231 		       unsigned long addr, int new_below);
3232 extern int split_vma(struct vma_iterator *vmi, struct vm_area_struct *,
3233 			 unsigned long addr, int new_below);
3234 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *);
3235 extern void unlink_file_vma(struct vm_area_struct *);
3236 extern struct vm_area_struct *copy_vma(struct vm_area_struct **,
3237 	unsigned long addr, unsigned long len, pgoff_t pgoff,
3238 	bool *need_rmap_locks);
3239 extern void exit_mmap(struct mm_struct *);
3240 
check_data_rlimit(unsigned long rlim,unsigned long new,unsigned long start,unsigned long end_data,unsigned long start_data)3241 static inline int check_data_rlimit(unsigned long rlim,
3242 				    unsigned long new,
3243 				    unsigned long start,
3244 				    unsigned long end_data,
3245 				    unsigned long start_data)
3246 {
3247 	if (rlim < RLIM_INFINITY) {
3248 		if (((new - start) + (end_data - start_data)) > rlim)
3249 			return -ENOSPC;
3250 	}
3251 
3252 	return 0;
3253 }
3254 
3255 extern int mm_take_all_locks(struct mm_struct *mm);
3256 extern void mm_drop_all_locks(struct mm_struct *mm);
3257 
3258 extern int set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
3259 extern int replace_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file);
3260 extern struct file *get_mm_exe_file(struct mm_struct *mm);
3261 extern struct file *get_task_exe_file(struct task_struct *task);
3262 
3263 extern bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long npages);
3264 extern void vm_stat_account(struct mm_struct *, vm_flags_t, long npages);
3265 
3266 extern bool vma_is_special_mapping(const struct vm_area_struct *vma,
3267 				   const struct vm_special_mapping *sm);
3268 extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm,
3269 				   unsigned long addr, unsigned long len,
3270 				   unsigned long flags,
3271 				   const struct vm_special_mapping *spec);
3272 /* This is an obsolete alternative to _install_special_mapping. */
3273 extern int install_special_mapping(struct mm_struct *mm,
3274 				   unsigned long addr, unsigned long len,
3275 				   unsigned long flags, struct page **pages);
3276 
3277 unsigned long randomize_stack_top(unsigned long stack_top);
3278 unsigned long randomize_page(unsigned long start, unsigned long range);
3279 
3280 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
3281 
3282 extern unsigned long mmap_region(struct file *file, unsigned long addr,
3283 	unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
3284 	struct list_head *uf);
3285 extern unsigned long do_mmap(struct file *file, unsigned long addr,
3286 	unsigned long len, unsigned long prot, unsigned long flags,
3287 	vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate,
3288 	struct list_head *uf);
3289 extern int do_vmi_munmap(struct vma_iterator *vmi, struct mm_struct *mm,
3290 			 unsigned long start, size_t len, struct list_head *uf,
3291 			 bool unlock);
3292 extern int do_munmap(struct mm_struct *, unsigned long, size_t,
3293 		     struct list_head *uf);
3294 extern int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior);
3295 
3296 #ifdef CONFIG_MMU
3297 extern int do_vma_munmap(struct vma_iterator *vmi, struct vm_area_struct *vma,
3298 			 unsigned long start, unsigned long end,
3299 			 struct list_head *uf, bool unlock);
3300 extern int __mm_populate(unsigned long addr, unsigned long len,
3301 			 int ignore_errors);
mm_populate(unsigned long addr,unsigned long len)3302 static inline void mm_populate(unsigned long addr, unsigned long len)
3303 {
3304 	/* Ignore errors */
3305 	(void) __mm_populate(addr, len, 1);
3306 }
3307 #else
mm_populate(unsigned long addr,unsigned long len)3308 static inline void mm_populate(unsigned long addr, unsigned long len) {}
3309 #endif
3310 
3311 /* These take the mm semaphore themselves */
3312 extern int __must_check vm_brk(unsigned long, unsigned long);
3313 extern int __must_check vm_brk_flags(unsigned long, unsigned long, unsigned long);
3314 extern int vm_munmap(unsigned long, size_t);
3315 extern unsigned long __must_check vm_mmap(struct file *, unsigned long,
3316         unsigned long, unsigned long,
3317         unsigned long, unsigned long);
3318 
3319 struct vm_unmapped_area_info {
3320 #define VM_UNMAPPED_AREA_TOPDOWN 1
3321 	unsigned long flags;
3322 	unsigned long length;
3323 	unsigned long low_limit;
3324 	unsigned long high_limit;
3325 	unsigned long align_mask;
3326 	unsigned long align_offset;
3327 };
3328 
3329 extern unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info);
3330 
3331 /* truncate.c */
3332 extern void truncate_inode_pages(struct address_space *, loff_t);
3333 extern void truncate_inode_pages_range(struct address_space *,
3334 				       loff_t lstart, loff_t lend);
3335 extern void truncate_inode_pages_final(struct address_space *);
3336 
3337 /* generic vm_area_ops exported for stackable file systems */
3338 extern vm_fault_t filemap_fault(struct vm_fault *vmf);
3339 extern vm_fault_t filemap_map_pages(struct vm_fault *vmf,
3340 		pgoff_t start_pgoff, pgoff_t end_pgoff);
3341 extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf);
3342 
3343 extern unsigned long stack_guard_gap;
3344 /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
3345 int expand_stack_locked(struct vm_area_struct *vma, unsigned long address);
3346 struct vm_area_struct *expand_stack(struct mm_struct * mm, unsigned long addr);
3347 
3348 /* CONFIG_STACK_GROWSUP still needs to grow downwards at some places */
3349 int expand_downwards(struct vm_area_struct *vma, unsigned long address);
3350 
3351 /* Look up the first VMA which satisfies  addr < vm_end,  NULL if none. */
3352 extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr);
3353 extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
3354 					     struct vm_area_struct **pprev);
3355 
3356 /*
3357  * Look up the first VMA which intersects the interval [start_addr, end_addr)
3358  * NULL if none.  Assume start_addr < end_addr.
3359  */
3360 struct vm_area_struct *find_vma_intersection(struct mm_struct *mm,
3361 			unsigned long start_addr, unsigned long end_addr);
3362 
3363 /**
3364  * vma_lookup() - Find a VMA at a specific address
3365  * @mm: The process address space.
3366  * @addr: The user address.
3367  *
3368  * Return: The vm_area_struct at the given address, %NULL otherwise.
3369  */
3370 static inline
vma_lookup(struct mm_struct * mm,unsigned long addr)3371 struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr)
3372 {
3373 	return mtree_load(&mm->mm_mt, addr);
3374 }
3375 
stack_guard_start_gap(struct vm_area_struct * vma)3376 static inline unsigned long stack_guard_start_gap(struct vm_area_struct *vma)
3377 {
3378 	if (vma->vm_flags & VM_GROWSDOWN)
3379 		return stack_guard_gap;
3380 
3381 	/* See reasoning around the VM_SHADOW_STACK definition */
3382 	if (vma->vm_flags & VM_SHADOW_STACK)
3383 		return PAGE_SIZE;
3384 
3385 	return 0;
3386 }
3387 
vm_start_gap(struct vm_area_struct * vma)3388 static inline unsigned long vm_start_gap(struct vm_area_struct *vma)
3389 {
3390 	unsigned long gap = stack_guard_start_gap(vma);
3391 	unsigned long vm_start = vma->vm_start;
3392 
3393 	vm_start -= gap;
3394 	if (vm_start > vma->vm_start)
3395 		vm_start = 0;
3396 	return vm_start;
3397 }
3398 
vm_end_gap(struct vm_area_struct * vma)3399 static inline unsigned long vm_end_gap(struct vm_area_struct *vma)
3400 {
3401 	unsigned long vm_end = vma->vm_end;
3402 
3403 	if (vma->vm_flags & VM_GROWSUP) {
3404 		vm_end += stack_guard_gap;
3405 		if (vm_end < vma->vm_end)
3406 			vm_end = -PAGE_SIZE;
3407 	}
3408 	return vm_end;
3409 }
3410 
vma_pages(struct vm_area_struct * vma)3411 static inline unsigned long vma_pages(struct vm_area_struct *vma)
3412 {
3413 	return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
3414 }
3415 
3416 /* Look up the first VMA which exactly match the interval vm_start ... vm_end */
find_exact_vma(struct mm_struct * mm,unsigned long vm_start,unsigned long vm_end)3417 static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm,
3418 				unsigned long vm_start, unsigned long vm_end)
3419 {
3420 	struct vm_area_struct *vma = vma_lookup(mm, vm_start);
3421 
3422 	if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end))
3423 		vma = NULL;
3424 
3425 	return vma;
3426 }
3427 
range_in_vma(struct vm_area_struct * vma,unsigned long start,unsigned long end)3428 static inline bool range_in_vma(struct vm_area_struct *vma,
3429 				unsigned long start, unsigned long end)
3430 {
3431 	return (vma && vma->vm_start <= start && end <= vma->vm_end);
3432 }
3433 
3434 #ifdef CONFIG_MMU
3435 pgprot_t vm_get_page_prot(unsigned long vm_flags);
3436 void vma_set_page_prot(struct vm_area_struct *vma);
3437 #else
vm_get_page_prot(unsigned long vm_flags)3438 static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
3439 {
3440 	return __pgprot(0);
3441 }
vma_set_page_prot(struct vm_area_struct * vma)3442 static inline void vma_set_page_prot(struct vm_area_struct *vma)
3443 {
3444 	vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
3445 }
3446 #endif
3447 
3448 void vma_set_file(struct vm_area_struct *vma, struct file *file);
3449 
3450 #ifdef CONFIG_NUMA_BALANCING
3451 unsigned long change_prot_numa(struct vm_area_struct *vma,
3452 			unsigned long start, unsigned long end);
3453 #endif
3454 
3455 struct vm_area_struct *find_extend_vma_locked(struct mm_struct *,
3456 		unsigned long addr);
3457 int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
3458 			unsigned long pfn, unsigned long size, pgprot_t);
3459 int remap_pfn_range_notrack(struct vm_area_struct *vma, unsigned long addr,
3460 		unsigned long pfn, unsigned long size, pgprot_t prot);
3461 int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *);
3462 int vm_insert_pages(struct vm_area_struct *vma, unsigned long addr,
3463 			struct page **pages, unsigned long *num);
3464 int vm_map_pages(struct vm_area_struct *vma, struct page **pages,
3465 				unsigned long num);
3466 int vm_map_pages_zero(struct vm_area_struct *vma, struct page **pages,
3467 				unsigned long num);
3468 vm_fault_t vmf_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
3469 			unsigned long pfn);
3470 vm_fault_t vmf_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
3471 			unsigned long pfn, pgprot_t pgprot);
3472 vm_fault_t vmf_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
3473 			pfn_t pfn);
3474 vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
3475 		unsigned long addr, pfn_t pfn);
3476 int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len);
3477 
vmf_insert_page(struct vm_area_struct * vma,unsigned long addr,struct page * page)3478 static inline vm_fault_t vmf_insert_page(struct vm_area_struct *vma,
3479 				unsigned long addr, struct page *page)
3480 {
3481 	int err = vm_insert_page(vma, addr, page);
3482 
3483 	if (err == -ENOMEM)
3484 		return VM_FAULT_OOM;
3485 	if (err < 0 && err != -EBUSY)
3486 		return VM_FAULT_SIGBUS;
3487 
3488 	return VM_FAULT_NOPAGE;
3489 }
3490 
3491 #ifndef io_remap_pfn_range
io_remap_pfn_range(struct vm_area_struct * vma,unsigned long addr,unsigned long pfn,unsigned long size,pgprot_t prot)3492 static inline int io_remap_pfn_range(struct vm_area_struct *vma,
3493 				     unsigned long addr, unsigned long pfn,
3494 				     unsigned long size, pgprot_t prot)
3495 {
3496 	return remap_pfn_range(vma, addr, pfn, size, pgprot_decrypted(prot));
3497 }
3498 #endif
3499 
vmf_error(int err)3500 static inline vm_fault_t vmf_error(int err)
3501 {
3502 	if (err == -ENOMEM)
3503 		return VM_FAULT_OOM;
3504 	else if (err == -EHWPOISON)
3505 		return VM_FAULT_HWPOISON;
3506 	return VM_FAULT_SIGBUS;
3507 }
3508 
3509 /*
3510  * Convert errno to return value for ->page_mkwrite() calls.
3511  *
3512  * This should eventually be merged with vmf_error() above, but will need a
3513  * careful audit of all vmf_error() callers.
3514  */
vmf_fs_error(int err)3515 static inline vm_fault_t vmf_fs_error(int err)
3516 {
3517 	if (err == 0)
3518 		return VM_FAULT_LOCKED;
3519 	if (err == -EFAULT || err == -EAGAIN)
3520 		return VM_FAULT_NOPAGE;
3521 	if (err == -ENOMEM)
3522 		return VM_FAULT_OOM;
3523 	/* -ENOSPC, -EDQUOT, -EIO ... */
3524 	return VM_FAULT_SIGBUS;
3525 }
3526 
3527 struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
3528 			 unsigned int foll_flags);
3529 
vm_fault_to_errno(vm_fault_t vm_fault,int foll_flags)3530 static inline int vm_fault_to_errno(vm_fault_t vm_fault, int foll_flags)
3531 {
3532 	if (vm_fault & VM_FAULT_OOM)
3533 		return -ENOMEM;
3534 	if (vm_fault & (VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE))
3535 		return (foll_flags & FOLL_HWPOISON) ? -EHWPOISON : -EFAULT;
3536 	if (vm_fault & (VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV))
3537 		return -EFAULT;
3538 	return 0;
3539 }
3540 
3541 /*
3542  * Indicates whether GUP can follow a PROT_NONE mapped page, or whether
3543  * a (NUMA hinting) fault is required.
3544  */
gup_can_follow_protnone(struct vm_area_struct * vma,unsigned int flags)3545 static inline bool gup_can_follow_protnone(struct vm_area_struct *vma,
3546 					   unsigned int flags)
3547 {
3548 	/*
3549 	 * If callers don't want to honor NUMA hinting faults, no need to
3550 	 * determine if we would actually have to trigger a NUMA hinting fault.
3551 	 */
3552 	if (!(flags & FOLL_HONOR_NUMA_FAULT))
3553 		return true;
3554 
3555 	/*
3556 	 * NUMA hinting faults don't apply in inaccessible (PROT_NONE) VMAs.
3557 	 *
3558 	 * Requiring a fault here even for inaccessible VMAs would mean that
3559 	 * FOLL_FORCE cannot make any progress, because handle_mm_fault()
3560 	 * refuses to process NUMA hinting faults in inaccessible VMAs.
3561 	 */
3562 	return !vma_is_accessible(vma);
3563 }
3564 
3565 typedef int (*pte_fn_t)(pte_t *pte, unsigned long addr, void *data);
3566 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address,
3567 			       unsigned long size, pte_fn_t fn, void *data);
3568 extern int apply_to_existing_page_range(struct mm_struct *mm,
3569 				   unsigned long address, unsigned long size,
3570 				   pte_fn_t fn, void *data);
3571 
3572 #ifdef CONFIG_PAGE_POISONING
3573 extern void __kernel_poison_pages(struct page *page, int numpages);
3574 extern void __kernel_unpoison_pages(struct page *page, int numpages);
3575 extern bool _page_poisoning_enabled_early;
3576 DECLARE_STATIC_KEY_FALSE(_page_poisoning_enabled);
page_poisoning_enabled(void)3577 static inline bool page_poisoning_enabled(void)
3578 {
3579 	return _page_poisoning_enabled_early;
3580 }
3581 /*
3582  * For use in fast paths after init_mem_debugging() has run, or when a
3583  * false negative result is not harmful when called too early.
3584  */
page_poisoning_enabled_static(void)3585 static inline bool page_poisoning_enabled_static(void)
3586 {
3587 	return static_branch_unlikely(&_page_poisoning_enabled);
3588 }
kernel_poison_pages(struct page * page,int numpages)3589 static inline void kernel_poison_pages(struct page *page, int numpages)
3590 {
3591 	if (page_poisoning_enabled_static())
3592 		__kernel_poison_pages(page, numpages);
3593 }
kernel_unpoison_pages(struct page * page,int numpages)3594 static inline void kernel_unpoison_pages(struct page *page, int numpages)
3595 {
3596 	if (page_poisoning_enabled_static())
3597 		__kernel_unpoison_pages(page, numpages);
3598 }
3599 #else
page_poisoning_enabled(void)3600 static inline bool page_poisoning_enabled(void) { return false; }
page_poisoning_enabled_static(void)3601 static inline bool page_poisoning_enabled_static(void) { return false; }
__kernel_poison_pages(struct page * page,int nunmpages)3602 static inline void __kernel_poison_pages(struct page *page, int nunmpages) { }
kernel_poison_pages(struct page * page,int numpages)3603 static inline void kernel_poison_pages(struct page *page, int numpages) { }
kernel_unpoison_pages(struct page * page,int numpages)3604 static inline void kernel_unpoison_pages(struct page *page, int numpages) { }
3605 #endif
3606 
3607 DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc);
want_init_on_alloc(gfp_t flags)3608 static inline bool want_init_on_alloc(gfp_t flags)
3609 {
3610 	if (static_branch_maybe(CONFIG_INIT_ON_ALLOC_DEFAULT_ON,
3611 				&init_on_alloc))
3612 		return true;
3613 	return flags & __GFP_ZERO;
3614 }
3615 
3616 DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free);
want_init_on_free(void)3617 static inline bool want_init_on_free(void)
3618 {
3619 	return static_branch_maybe(CONFIG_INIT_ON_FREE_DEFAULT_ON,
3620 				   &init_on_free);
3621 }
3622 
3623 extern bool _debug_pagealloc_enabled_early;
3624 DECLARE_STATIC_KEY_FALSE(_debug_pagealloc_enabled);
3625 
debug_pagealloc_enabled(void)3626 static inline bool debug_pagealloc_enabled(void)
3627 {
3628 	return IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) &&
3629 		_debug_pagealloc_enabled_early;
3630 }
3631 
3632 /*
3633  * For use in fast paths after mem_debugging_and_hardening_init() has run,
3634  * or when a false negative result is not harmful when called too early.
3635  */
debug_pagealloc_enabled_static(void)3636 static inline bool debug_pagealloc_enabled_static(void)
3637 {
3638 	if (!IS_ENABLED(CONFIG_DEBUG_PAGEALLOC))
3639 		return false;
3640 
3641 	return static_branch_unlikely(&_debug_pagealloc_enabled);
3642 }
3643 
3644 /*
3645  * To support DEBUG_PAGEALLOC architecture must ensure that
3646  * __kernel_map_pages() never fails
3647  */
3648 extern void __kernel_map_pages(struct page *page, int numpages, int enable);
3649 #ifdef CONFIG_DEBUG_PAGEALLOC
debug_pagealloc_map_pages(struct page * page,int numpages)3650 static inline void debug_pagealloc_map_pages(struct page *page, int numpages)
3651 {
3652 	if (debug_pagealloc_enabled_static())
3653 		__kernel_map_pages(page, numpages, 1);
3654 }
3655 
debug_pagealloc_unmap_pages(struct page * page,int numpages)3656 static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages)
3657 {
3658 	if (debug_pagealloc_enabled_static())
3659 		__kernel_map_pages(page, numpages, 0);
3660 }
3661 
3662 extern unsigned int _debug_guardpage_minorder;
3663 DECLARE_STATIC_KEY_FALSE(_debug_guardpage_enabled);
3664 
debug_guardpage_minorder(void)3665 static inline unsigned int debug_guardpage_minorder(void)
3666 {
3667 	return _debug_guardpage_minorder;
3668 }
3669 
debug_guardpage_enabled(void)3670 static inline bool debug_guardpage_enabled(void)
3671 {
3672 	return static_branch_unlikely(&_debug_guardpage_enabled);
3673 }
3674 
page_is_guard(struct page * page)3675 static inline bool page_is_guard(struct page *page)
3676 {
3677 	if (!debug_guardpage_enabled())
3678 		return false;
3679 
3680 	return PageGuard(page);
3681 }
3682 
3683 bool __set_page_guard(struct zone *zone, struct page *page, unsigned int order,
3684 		      int migratetype);
set_page_guard(struct zone * zone,struct page * page,unsigned int order,int migratetype)3685 static inline bool set_page_guard(struct zone *zone, struct page *page,
3686 				  unsigned int order, int migratetype)
3687 {
3688 	if (!debug_guardpage_enabled())
3689 		return false;
3690 	return __set_page_guard(zone, page, order, migratetype);
3691 }
3692 
3693 void __clear_page_guard(struct zone *zone, struct page *page, unsigned int order,
3694 			int migratetype);
clear_page_guard(struct zone * zone,struct page * page,unsigned int order,int migratetype)3695 static inline void clear_page_guard(struct zone *zone, struct page *page,
3696 				    unsigned int order, int migratetype)
3697 {
3698 	if (!debug_guardpage_enabled())
3699 		return;
3700 	__clear_page_guard(zone, page, order, migratetype);
3701 }
3702 
3703 #else	/* CONFIG_DEBUG_PAGEALLOC */
debug_pagealloc_map_pages(struct page * page,int numpages)3704 static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {}
debug_pagealloc_unmap_pages(struct page * page,int numpages)3705 static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {}
debug_guardpage_minorder(void)3706 static inline unsigned int debug_guardpage_minorder(void) { return 0; }
debug_guardpage_enabled(void)3707 static inline bool debug_guardpage_enabled(void) { return false; }
page_is_guard(struct page * page)3708 static inline bool page_is_guard(struct page *page) { return false; }
set_page_guard(struct zone * zone,struct page * page,unsigned int order,int migratetype)3709 static inline bool set_page_guard(struct zone *zone, struct page *page,
3710 			unsigned int order, int migratetype) { return false; }
clear_page_guard(struct zone * zone,struct page * page,unsigned int order,int migratetype)3711 static inline void clear_page_guard(struct zone *zone, struct page *page,
3712 				unsigned int order, int migratetype) {}
3713 #endif	/* CONFIG_DEBUG_PAGEALLOC */
3714 
3715 #ifdef __HAVE_ARCH_GATE_AREA
3716 extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
3717 extern int in_gate_area_no_mm(unsigned long addr);
3718 extern int in_gate_area(struct mm_struct *mm, unsigned long addr);
3719 #else
get_gate_vma(struct mm_struct * mm)3720 static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
3721 {
3722 	return NULL;
3723 }
in_gate_area_no_mm(unsigned long addr)3724 static inline int in_gate_area_no_mm(unsigned long addr) { return 0; }
in_gate_area(struct mm_struct * mm,unsigned long addr)3725 static inline int in_gate_area(struct mm_struct *mm, unsigned long addr)
3726 {
3727 	return 0;
3728 }
3729 #endif	/* __HAVE_ARCH_GATE_AREA */
3730 
3731 extern bool process_shares_mm(struct task_struct *p, struct mm_struct *mm);
3732 
3733 #ifdef CONFIG_SYSCTL
3734 extern int sysctl_drop_caches;
3735 int drop_caches_sysctl_handler(struct ctl_table *, int, void *, size_t *,
3736 		loff_t *);
3737 #endif
3738 
3739 void drop_slab(void);
3740 
3741 #ifndef CONFIG_MMU
3742 #define randomize_va_space 0
3743 #else
3744 extern int randomize_va_space;
3745 #endif
3746 
3747 const char * arch_vma_name(struct vm_area_struct *vma);
3748 #ifdef CONFIG_MMU
3749 void print_vma_addr(char *prefix, unsigned long rip);
3750 #else
print_vma_addr(char * prefix,unsigned long rip)3751 static inline void print_vma_addr(char *prefix, unsigned long rip)
3752 {
3753 }
3754 #endif
3755 
3756 void *sparse_buffer_alloc(unsigned long size);
3757 struct page * __populate_section_memmap(unsigned long pfn,
3758 		unsigned long nr_pages, int nid, struct vmem_altmap *altmap,
3759 		struct dev_pagemap *pgmap);
3760 void pmd_init(void *addr);
3761 void pud_init(void *addr);
3762 pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);
3763 p4d_t *vmemmap_p4d_populate(pgd_t *pgd, unsigned long addr, int node);
3764 pud_t *vmemmap_pud_populate(p4d_t *p4d, unsigned long addr, int node);
3765 pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);
3766 pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node,
3767 			    struct vmem_altmap *altmap, struct page *reuse);
3768 void *vmemmap_alloc_block(unsigned long size, int node);
3769 struct vmem_altmap;
3770 void *vmemmap_alloc_block_buf(unsigned long size, int node,
3771 			      struct vmem_altmap *altmap);
3772 void vmemmap_verify(pte_t *, int, unsigned long, unsigned long);
3773 void vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
3774 		     unsigned long addr, unsigned long next);
3775 int vmemmap_check_pmd(pmd_t *pmd, int node,
3776 		      unsigned long addr, unsigned long next);
3777 int vmemmap_populate_basepages(unsigned long start, unsigned long end,
3778 			       int node, struct vmem_altmap *altmap);
3779 int vmemmap_populate_hugepages(unsigned long start, unsigned long end,
3780 			       int node, struct vmem_altmap *altmap);
3781 int vmemmap_populate(unsigned long start, unsigned long end, int node,
3782 		struct vmem_altmap *altmap);
3783 void vmemmap_populate_print_last(void);
3784 #ifdef CONFIG_MEMORY_HOTPLUG
3785 void vmemmap_free(unsigned long start, unsigned long end,
3786 		struct vmem_altmap *altmap);
3787 #endif
3788 
3789 #define VMEMMAP_RESERVE_NR	2
3790 #ifdef CONFIG_ARCH_WANT_OPTIMIZE_DAX_VMEMMAP
__vmemmap_can_optimize(struct vmem_altmap * altmap,struct dev_pagemap * pgmap)3791 static inline bool __vmemmap_can_optimize(struct vmem_altmap *altmap,
3792 					  struct dev_pagemap *pgmap)
3793 {
3794 	unsigned long nr_pages;
3795 	unsigned long nr_vmemmap_pages;
3796 
3797 	if (!pgmap || !is_power_of_2(sizeof(struct page)))
3798 		return false;
3799 
3800 	nr_pages = pgmap_vmemmap_nr(pgmap);
3801 	nr_vmemmap_pages = ((nr_pages * sizeof(struct page)) >> PAGE_SHIFT);
3802 	/*
3803 	 * For vmemmap optimization with DAX we need minimum 2 vmemmap
3804 	 * pages. See layout diagram in Documentation/mm/vmemmap_dedup.rst
3805 	 */
3806 	return !altmap && (nr_vmemmap_pages > VMEMMAP_RESERVE_NR);
3807 }
3808 /*
3809  * If we don't have an architecture override, use the generic rule
3810  */
3811 #ifndef vmemmap_can_optimize
3812 #define vmemmap_can_optimize __vmemmap_can_optimize
3813 #endif
3814 
3815 #else
vmemmap_can_optimize(struct vmem_altmap * altmap,struct dev_pagemap * pgmap)3816 static inline bool vmemmap_can_optimize(struct vmem_altmap *altmap,
3817 					   struct dev_pagemap *pgmap)
3818 {
3819 	return false;
3820 }
3821 #endif
3822 
3823 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
3824 				  unsigned long nr_pages);
3825 
3826 enum mf_flags {
3827 	MF_COUNT_INCREASED = 1 << 0,
3828 	MF_ACTION_REQUIRED = 1 << 1,
3829 	MF_MUST_KILL = 1 << 2,
3830 	MF_SOFT_OFFLINE = 1 << 3,
3831 	MF_UNPOISON = 1 << 4,
3832 	MF_SW_SIMULATED = 1 << 5,
3833 	MF_NO_RETRY = 1 << 6,
3834 };
3835 int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index,
3836 		      unsigned long count, int mf_flags);
3837 extern int memory_failure(unsigned long pfn, int flags);
3838 extern void memory_failure_queue_kick(int cpu);
3839 extern int unpoison_memory(unsigned long pfn);
3840 extern void shake_page(struct page *p);
3841 extern atomic_long_t num_poisoned_pages __read_mostly;
3842 extern int soft_offline_page(unsigned long pfn, int flags);
3843 #ifdef CONFIG_MEMORY_FAILURE
3844 /*
3845  * Sysfs entries for memory failure handling statistics.
3846  */
3847 extern const struct attribute_group memory_failure_attr_group;
3848 extern void memory_failure_queue(unsigned long pfn, int flags);
3849 extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
3850 					bool *migratable_cleared);
3851 void num_poisoned_pages_inc(unsigned long pfn);
3852 void num_poisoned_pages_sub(unsigned long pfn, long i);
3853 struct task_struct *task_early_kill(struct task_struct *tsk, int force_early);
3854 #else
memory_failure_queue(unsigned long pfn,int flags)3855 static inline void memory_failure_queue(unsigned long pfn, int flags)
3856 {
3857 }
3858 
__get_huge_page_for_hwpoison(unsigned long pfn,int flags,bool * migratable_cleared)3859 static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
3860 					bool *migratable_cleared)
3861 {
3862 	return 0;
3863 }
3864 
num_poisoned_pages_inc(unsigned long pfn)3865 static inline void num_poisoned_pages_inc(unsigned long pfn)
3866 {
3867 }
3868 
num_poisoned_pages_sub(unsigned long pfn,long i)3869 static inline void num_poisoned_pages_sub(unsigned long pfn, long i)
3870 {
3871 }
3872 #endif
3873 
3874 #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_KSM)
3875 void add_to_kill_ksm(struct task_struct *tsk, struct page *p,
3876 		     struct vm_area_struct *vma, struct list_head *to_kill,
3877 		     unsigned long ksm_addr);
3878 #endif
3879 
3880 #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG)
3881 extern void memblk_nr_poison_inc(unsigned long pfn);
3882 extern void memblk_nr_poison_sub(unsigned long pfn, long i);
3883 #else
memblk_nr_poison_inc(unsigned long pfn)3884 static inline void memblk_nr_poison_inc(unsigned long pfn)
3885 {
3886 }
3887 
memblk_nr_poison_sub(unsigned long pfn,long i)3888 static inline void memblk_nr_poison_sub(unsigned long pfn, long i)
3889 {
3890 }
3891 #endif
3892 
3893 #ifndef arch_memory_failure
arch_memory_failure(unsigned long pfn,int flags)3894 static inline int arch_memory_failure(unsigned long pfn, int flags)
3895 {
3896 	return -ENXIO;
3897 }
3898 #endif
3899 
3900 #ifndef arch_is_platform_page
arch_is_platform_page(u64 paddr)3901 static inline bool arch_is_platform_page(u64 paddr)
3902 {
3903 	return false;
3904 }
3905 #endif
3906 
3907 /*
3908  * Error handlers for various types of pages.
3909  */
3910 enum mf_result {
3911 	MF_IGNORED,	/* Error: cannot be handled */
3912 	MF_FAILED,	/* Error: handling failed */
3913 	MF_DELAYED,	/* Will be handled later */
3914 	MF_RECOVERED,	/* Successfully recovered */
3915 };
3916 
3917 enum mf_action_page_type {
3918 	MF_MSG_KERNEL,
3919 	MF_MSG_KERNEL_HIGH_ORDER,
3920 	MF_MSG_SLAB,
3921 	MF_MSG_DIFFERENT_COMPOUND,
3922 	MF_MSG_HUGE,
3923 	MF_MSG_FREE_HUGE,
3924 	MF_MSG_UNMAP_FAILED,
3925 	MF_MSG_DIRTY_SWAPCACHE,
3926 	MF_MSG_CLEAN_SWAPCACHE,
3927 	MF_MSG_DIRTY_MLOCKED_LRU,
3928 	MF_MSG_CLEAN_MLOCKED_LRU,
3929 	MF_MSG_DIRTY_UNEVICTABLE_LRU,
3930 	MF_MSG_CLEAN_UNEVICTABLE_LRU,
3931 	MF_MSG_DIRTY_LRU,
3932 	MF_MSG_CLEAN_LRU,
3933 	MF_MSG_TRUNCATED_LRU,
3934 	MF_MSG_BUDDY,
3935 	MF_MSG_DAX,
3936 	MF_MSG_UNSPLIT_THP,
3937 	MF_MSG_UNKNOWN,
3938 };
3939 
3940 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS)
3941 extern void clear_huge_page(struct page *page,
3942 			    unsigned long addr_hint,
3943 			    unsigned int pages_per_huge_page);
3944 int copy_user_large_folio(struct folio *dst, struct folio *src,
3945 			  unsigned long addr_hint,
3946 			  struct vm_area_struct *vma);
3947 long copy_folio_from_user(struct folio *dst_folio,
3948 			   const void __user *usr_src,
3949 			   bool allow_pagefault);
3950 
3951 /**
3952  * vma_is_special_huge - Are transhuge page-table entries considered special?
3953  * @vma: Pointer to the struct vm_area_struct to consider
3954  *
3955  * Whether transhuge page-table entries are considered "special" following
3956  * the definition in vm_normal_page().
3957  *
3958  * Return: true if transhuge page-table entries should be considered special,
3959  * false otherwise.
3960  */
vma_is_special_huge(const struct vm_area_struct * vma)3961 static inline bool vma_is_special_huge(const struct vm_area_struct *vma)
3962 {
3963 	return vma_is_dax(vma) || (vma->vm_file &&
3964 				   (vma->vm_flags & (VM_PFNMAP | VM_MIXEDMAP)));
3965 }
3966 
3967 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
3968 
3969 #if MAX_NUMNODES > 1
3970 void __init setup_nr_node_ids(void);
3971 #else
setup_nr_node_ids(void)3972 static inline void setup_nr_node_ids(void) {}
3973 #endif
3974 
3975 extern int memcmp_pages(struct page *page1, struct page *page2);
3976 
pages_identical(struct page * page1,struct page * page2)3977 static inline int pages_identical(struct page *page1, struct page *page2)
3978 {
3979 	return !memcmp_pages(page1, page2);
3980 }
3981 
3982 #ifdef CONFIG_MAPPING_DIRTY_HELPERS
3983 unsigned long clean_record_shared_mapping_range(struct address_space *mapping,
3984 						pgoff_t first_index, pgoff_t nr,
3985 						pgoff_t bitmap_pgoff,
3986 						unsigned long *bitmap,
3987 						pgoff_t *start,
3988 						pgoff_t *end);
3989 
3990 unsigned long wp_shared_mapping_range(struct address_space *mapping,
3991 				      pgoff_t first_index, pgoff_t nr);
3992 #endif
3993 
3994 extern int sysctl_nr_trim_pages;
3995 
3996 #ifdef CONFIG_PRINTK
3997 void mem_dump_obj(void *object);
3998 #else
mem_dump_obj(void * object)3999 static inline void mem_dump_obj(void *object) {}
4000 #endif
4001 
4002 /**
4003  * seal_check_future_write - Check for F_SEAL_FUTURE_WRITE flag and handle it
4004  * @seals: the seals to check
4005  * @vma: the vma to operate on
4006  *
4007  * Check whether F_SEAL_FUTURE_WRITE is set; if so, do proper check/handling on
4008  * the vma flags.  Return 0 if check pass, or <0 for errors.
4009  */
seal_check_future_write(int seals,struct vm_area_struct * vma)4010 static inline int seal_check_future_write(int seals, struct vm_area_struct *vma)
4011 {
4012 	if (seals & F_SEAL_FUTURE_WRITE) {
4013 		/*
4014 		 * New PROT_WRITE and MAP_SHARED mmaps are not allowed when
4015 		 * "future write" seal active.
4016 		 */
4017 		if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE))
4018 			return -EPERM;
4019 
4020 		/*
4021 		 * Since an F_SEAL_FUTURE_WRITE sealed memfd can be mapped as
4022 		 * MAP_SHARED and read-only, take care to not allow mprotect to
4023 		 * revert protections on such mappings. Do this only for shared
4024 		 * mappings. For private mappings, don't need to mask
4025 		 * VM_MAYWRITE as we still want them to be COW-writable.
4026 		 */
4027 		if (vma->vm_flags & VM_SHARED)
4028 			vm_flags_clear(vma, VM_MAYWRITE);
4029 	}
4030 
4031 	return 0;
4032 }
4033 
4034 #ifdef CONFIG_ANON_VMA_NAME
4035 int madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
4036 			  unsigned long len_in,
4037 			  struct anon_vma_name *anon_name);
4038 #else
4039 static inline int
madvise_set_anon_name(struct mm_struct * mm,unsigned long start,unsigned long len_in,struct anon_vma_name * anon_name)4040 madvise_set_anon_name(struct mm_struct *mm, unsigned long start,
4041 		      unsigned long len_in, struct anon_vma_name *anon_name) {
4042 	return 0;
4043 }
4044 #endif
4045 
4046 #ifdef CONFIG_UNACCEPTED_MEMORY
4047 
4048 bool range_contains_unaccepted_memory(phys_addr_t start, phys_addr_t end);
4049 void accept_memory(phys_addr_t start, phys_addr_t end);
4050 
4051 #else
4052 
range_contains_unaccepted_memory(phys_addr_t start,phys_addr_t end)4053 static inline bool range_contains_unaccepted_memory(phys_addr_t start,
4054 						    phys_addr_t end)
4055 {
4056 	return false;
4057 }
4058 
accept_memory(phys_addr_t start,phys_addr_t end)4059 static inline void accept_memory(phys_addr_t start, phys_addr_t end)
4060 {
4061 }
4062 
4063 #endif
4064 
4065 #endif /* _LINUX_MM_H */
4066