1 #ifndef _LINUX_MM_H 2 #define _LINUX_MM_H 3 4 #include <linux/errno.h> 5 6 #ifdef __KERNEL__ 7 8 #include <linux/mmdebug.h> 9 #include <linux/gfp.h> 10 #include <linux/bug.h> 11 #include <linux/list.h> 12 #include <linux/mmzone.h> 13 #include <linux/rbtree.h> 14 #include <linux/atomic.h> 15 #include <linux/debug_locks.h> 16 #include <linux/mm_types.h> 17 #include <linux/range.h> 18 #include <linux/pfn.h> 19 #include <linux/bit_spinlock.h> 20 #include <linux/shrinker.h> 21 22 struct mempolicy; 23 struct anon_vma; 24 struct anon_vma_chain; 25 struct file_ra_state; 26 struct user_struct; 27 struct writeback_control; 28 29 #ifndef CONFIG_NEED_MULTIPLE_NODES /* Don't use mapnrs, do it properly */ 30 extern unsigned long max_mapnr; 31 32 static inline void set_max_mapnr(unsigned long limit) 33 { 34 max_mapnr = limit; 35 } 36 #else 37 static inline void set_max_mapnr(unsigned long limit) { } 38 #endif 39 40 extern unsigned long totalram_pages; 41 extern void * high_memory; 42 extern int page_cluster; 43 44 #ifdef CONFIG_SYSCTL 45 extern int sysctl_legacy_va_layout; 46 #else 47 #define sysctl_legacy_va_layout 0 48 #endif 49 50 #include <asm/page.h> 51 #include <asm/pgtable.h> 52 #include <asm/processor.h> 53 54 #ifndef __pa_symbol 55 #define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0)) 56 #endif 57 58 extern unsigned long sysctl_user_reserve_kbytes; 59 extern unsigned long sysctl_admin_reserve_kbytes; 60 61 extern int sysctl_overcommit_memory; 62 extern int sysctl_overcommit_ratio; 63 extern unsigned long sysctl_overcommit_kbytes; 64 65 extern int overcommit_ratio_handler(struct ctl_table *, int, void __user *, 66 size_t *, loff_t *); 67 extern int overcommit_kbytes_handler(struct ctl_table *, int, void __user *, 68 size_t *, loff_t *); 69 70 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n)) 71 72 /* to align the pointer to the (next) page boundary */ 73 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE) 74 75 /* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */ 76 #define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)addr, PAGE_SIZE) 77 78 /* 79 * Linux kernel virtual memory manager primitives. 80 * The idea being to have a "virtual" mm in the same way 81 * we have a virtual fs - giving a cleaner interface to the 82 * mm details, and allowing different kinds of memory mappings 83 * (from shared memory to executable loading to arbitrary 84 * mmap() functions). 85 */ 86 87 extern struct kmem_cache *vm_area_cachep; 88 89 #ifndef CONFIG_MMU 90 extern struct rb_root nommu_region_tree; 91 extern struct rw_semaphore nommu_region_sem; 92 93 extern unsigned int kobjsize(const void *objp); 94 #endif 95 96 /* 97 * vm_flags in vm_area_struct, see mm_types.h. 98 */ 99 #define VM_NONE 0x00000000 100 101 #define VM_READ 0x00000001 /* currently active flags */ 102 #define VM_WRITE 0x00000002 103 #define VM_EXEC 0x00000004 104 #define VM_SHARED 0x00000008 105 106 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */ 107 #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */ 108 #define VM_MAYWRITE 0x00000020 109 #define VM_MAYEXEC 0x00000040 110 #define VM_MAYSHARE 0x00000080 111 112 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */ 113 #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */ 114 #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */ 115 116 #define VM_LOCKED 0x00002000 117 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */ 118 119 /* Used by sys_madvise() */ 120 #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ 121 #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */ 122 123 #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ 124 #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ 125 #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ 126 #define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */ 127 #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ 128 #define VM_NONLINEAR 0x00800000 /* Is non-linear (remap_file_pages) */ 129 #define VM_ARCH_1 0x01000000 /* Architecture-specific flag */ 130 #define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */ 131 132 #ifdef CONFIG_MEM_SOFT_DIRTY 133 # define VM_SOFTDIRTY 0x08000000 /* Not soft dirty clean area */ 134 #else 135 # define VM_SOFTDIRTY 0 136 #endif 137 138 #define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */ 139 #define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */ 140 #define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */ 141 #define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */ 142 143 #if defined(CONFIG_X86) 144 # define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */ 145 #elif defined(CONFIG_PPC) 146 # define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */ 147 #elif defined(CONFIG_PARISC) 148 # define VM_GROWSUP VM_ARCH_1 149 #elif defined(CONFIG_METAG) 150 # define VM_GROWSUP VM_ARCH_1 151 #elif defined(CONFIG_IA64) 152 # define VM_GROWSUP VM_ARCH_1 153 #elif !defined(CONFIG_MMU) 154 # define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */ 155 #endif 156 157 #ifndef VM_GROWSUP 158 # define VM_GROWSUP VM_NONE 159 #endif 160 161 /* Bits set in the VMA until the stack is in its final location */ 162 #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ) 163 164 #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */ 165 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS 166 #endif 167 168 #ifdef CONFIG_STACK_GROWSUP 169 #define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 170 #else 171 #define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 172 #endif 173 174 /* 175 * Special vmas that are non-mergable, non-mlock()able. 176 * Note: mm/huge_memory.c VM_NO_THP depends on this definition. 177 */ 178 #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP) 179 180 /* This mask defines which mm->def_flags a process can inherit its parent */ 181 #define VM_INIT_DEF_MASK VM_NOHUGEPAGE 182 183 /* 184 * mapping from the currently active vm_flags protection bits (the 185 * low four bits) to a page protection mask.. 186 */ 187 extern pgprot_t protection_map[16]; 188 189 #define FAULT_FLAG_WRITE 0x01 /* Fault was a write access */ 190 #define FAULT_FLAG_NONLINEAR 0x02 /* Fault was via a nonlinear mapping */ 191 #define FAULT_FLAG_MKWRITE 0x04 /* Fault was mkwrite of existing pte */ 192 #define FAULT_FLAG_ALLOW_RETRY 0x08 /* Retry fault if blocking */ 193 #define FAULT_FLAG_RETRY_NOWAIT 0x10 /* Don't drop mmap_sem and wait when retrying */ 194 #define FAULT_FLAG_KILLABLE 0x20 /* The fault task is in SIGKILL killable region */ 195 #define FAULT_FLAG_TRIED 0x40 /* second try */ 196 #define FAULT_FLAG_USER 0x80 /* The fault originated in userspace */ 197 198 /* 199 * vm_fault is filled by the the pagefault handler and passed to the vma's 200 * ->fault function. The vma's ->fault is responsible for returning a bitmask 201 * of VM_FAULT_xxx flags that give details about how the fault was handled. 202 * 203 * pgoff should be used in favour of virtual_address, if possible. If pgoff 204 * is used, one may implement ->remap_pages to get nonlinear mapping support. 205 */ 206 struct vm_fault { 207 unsigned int flags; /* FAULT_FLAG_xxx flags */ 208 pgoff_t pgoff; /* Logical page offset based on vma */ 209 void __user *virtual_address; /* Faulting virtual address */ 210 211 struct page *page; /* ->fault handlers should return a 212 * page here, unless VM_FAULT_NOPAGE 213 * is set (which is also implied by 214 * VM_FAULT_ERROR). 215 */ 216 /* for ->map_pages() only */ 217 pgoff_t max_pgoff; /* map pages for offset from pgoff till 218 * max_pgoff inclusive */ 219 pte_t *pte; /* pte entry associated with ->pgoff */ 220 }; 221 222 /* 223 * These are the virtual MM functions - opening of an area, closing and 224 * unmapping it (needed to keep files on disk up-to-date etc), pointer 225 * to the functions called when a no-page or a wp-page exception occurs. 226 */ 227 struct vm_operations_struct { 228 void (*open)(struct vm_area_struct * area); 229 void (*close)(struct vm_area_struct * area); 230 int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf); 231 void (*map_pages)(struct vm_area_struct *vma, struct vm_fault *vmf); 232 233 /* notification that a previously read-only page is about to become 234 * writable, if an error is returned it will cause a SIGBUS */ 235 int (*page_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf); 236 237 /* called by access_process_vm when get_user_pages() fails, typically 238 * for use by special VMAs that can switch between memory and hardware 239 */ 240 int (*access)(struct vm_area_struct *vma, unsigned long addr, 241 void *buf, int len, int write); 242 243 /* Called by the /proc/PID/maps code to ask the vma whether it 244 * has a special name. Returning non-NULL will also cause this 245 * vma to be dumped unconditionally. */ 246 const char *(*name)(struct vm_area_struct *vma); 247 248 #ifdef CONFIG_NUMA 249 /* 250 * set_policy() op must add a reference to any non-NULL @new mempolicy 251 * to hold the policy upon return. Caller should pass NULL @new to 252 * remove a policy and fall back to surrounding context--i.e. do not 253 * install a MPOL_DEFAULT policy, nor the task or system default 254 * mempolicy. 255 */ 256 int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); 257 258 /* 259 * get_policy() op must add reference [mpol_get()] to any policy at 260 * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure 261 * in mm/mempolicy.c will do this automatically. 262 * get_policy() must NOT add a ref if the policy at (vma,addr) is not 263 * marked as MPOL_SHARED. vma policies are protected by the mmap_sem. 264 * If no [shared/vma] mempolicy exists at the addr, get_policy() op 265 * must return NULL--i.e., do not "fallback" to task or system default 266 * policy. 267 */ 268 struct mempolicy *(*get_policy)(struct vm_area_struct *vma, 269 unsigned long addr); 270 int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from, 271 const nodemask_t *to, unsigned long flags); 272 #endif 273 /* called by sys_remap_file_pages() to populate non-linear mapping */ 274 int (*remap_pages)(struct vm_area_struct *vma, unsigned long addr, 275 unsigned long size, pgoff_t pgoff); 276 }; 277 278 struct mmu_gather; 279 struct inode; 280 281 #define page_private(page) ((page)->private) 282 #define set_page_private(page, v) ((page)->private = (v)) 283 284 /* It's valid only if the page is free path or free_list */ 285 static inline void set_freepage_migratetype(struct page *page, int migratetype) 286 { 287 page->index = migratetype; 288 } 289 290 /* It's valid only if the page is free path or free_list */ 291 static inline int get_freepage_migratetype(struct page *page) 292 { 293 return page->index; 294 } 295 296 /* 297 * FIXME: take this include out, include page-flags.h in 298 * files which need it (119 of them) 299 */ 300 #include <linux/page-flags.h> 301 #include <linux/huge_mm.h> 302 303 /* 304 * Methods to modify the page usage count. 305 * 306 * What counts for a page usage: 307 * - cache mapping (page->mapping) 308 * - private data (page->private) 309 * - page mapped in a task's page tables, each mapping 310 * is counted separately 311 * 312 * Also, many kernel routines increase the page count before a critical 313 * routine so they can be sure the page doesn't go away from under them. 314 */ 315 316 /* 317 * Drop a ref, return true if the refcount fell to zero (the page has no users) 318 */ 319 static inline int put_page_testzero(struct page *page) 320 { 321 VM_BUG_ON_PAGE(atomic_read(&page->_count) == 0, page); 322 return atomic_dec_and_test(&page->_count); 323 } 324 325 /* 326 * Try to grab a ref unless the page has a refcount of zero, return false if 327 * that is the case. 328 * This can be called when MMU is off so it must not access 329 * any of the virtual mappings. 330 */ 331 static inline int get_page_unless_zero(struct page *page) 332 { 333 return atomic_inc_not_zero(&page->_count); 334 } 335 336 /* 337 * Try to drop a ref unless the page has a refcount of one, return false if 338 * that is the case. 339 * This is to make sure that the refcount won't become zero after this drop. 340 * This can be called when MMU is off so it must not access 341 * any of the virtual mappings. 342 */ 343 static inline int put_page_unless_one(struct page *page) 344 { 345 return atomic_add_unless(&page->_count, -1, 1); 346 } 347 348 extern int page_is_ram(unsigned long pfn); 349 350 /* Support for virtually mapped pages */ 351 struct page *vmalloc_to_page(const void *addr); 352 unsigned long vmalloc_to_pfn(const void *addr); 353 354 /* 355 * Determine if an address is within the vmalloc range 356 * 357 * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there 358 * is no special casing required. 359 */ 360 static inline int is_vmalloc_addr(const void *x) 361 { 362 #ifdef CONFIG_MMU 363 unsigned long addr = (unsigned long)x; 364 365 return addr >= VMALLOC_START && addr < VMALLOC_END; 366 #else 367 return 0; 368 #endif 369 } 370 #ifdef CONFIG_MMU 371 extern int is_vmalloc_or_module_addr(const void *x); 372 #else 373 static inline int is_vmalloc_or_module_addr(const void *x) 374 { 375 return 0; 376 } 377 #endif 378 379 extern void kvfree(const void *addr); 380 381 static inline void compound_lock(struct page *page) 382 { 383 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 384 VM_BUG_ON_PAGE(PageSlab(page), page); 385 bit_spin_lock(PG_compound_lock, &page->flags); 386 #endif 387 } 388 389 static inline void compound_unlock(struct page *page) 390 { 391 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 392 VM_BUG_ON_PAGE(PageSlab(page), page); 393 bit_spin_unlock(PG_compound_lock, &page->flags); 394 #endif 395 } 396 397 static inline unsigned long compound_lock_irqsave(struct page *page) 398 { 399 unsigned long uninitialized_var(flags); 400 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 401 local_irq_save(flags); 402 compound_lock(page); 403 #endif 404 return flags; 405 } 406 407 static inline void compound_unlock_irqrestore(struct page *page, 408 unsigned long flags) 409 { 410 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 411 compound_unlock(page); 412 local_irq_restore(flags); 413 #endif 414 } 415 416 static inline struct page *compound_head_by_tail(struct page *tail) 417 { 418 struct page *head = tail->first_page; 419 420 /* 421 * page->first_page may be a dangling pointer to an old 422 * compound page, so recheck that it is still a tail 423 * page before returning. 424 */ 425 smp_rmb(); 426 if (likely(PageTail(tail))) 427 return head; 428 return tail; 429 } 430 431 static inline struct page *compound_head(struct page *page) 432 { 433 if (unlikely(PageTail(page))) 434 return compound_head_by_tail(page); 435 return page; 436 } 437 438 /* 439 * The atomic page->_mapcount, starts from -1: so that transitions 440 * both from it and to it can be tracked, using atomic_inc_and_test 441 * and atomic_add_negative(-1). 442 */ 443 static inline void page_mapcount_reset(struct page *page) 444 { 445 atomic_set(&(page)->_mapcount, -1); 446 } 447 448 static inline int page_mapcount(struct page *page) 449 { 450 return atomic_read(&(page)->_mapcount) + 1; 451 } 452 453 static inline int page_count(struct page *page) 454 { 455 return atomic_read(&compound_head(page)->_count); 456 } 457 458 #ifdef CONFIG_HUGETLB_PAGE 459 extern int PageHeadHuge(struct page *page_head); 460 #else /* CONFIG_HUGETLB_PAGE */ 461 static inline int PageHeadHuge(struct page *page_head) 462 { 463 return 0; 464 } 465 #endif /* CONFIG_HUGETLB_PAGE */ 466 467 static inline bool __compound_tail_refcounted(struct page *page) 468 { 469 return !PageSlab(page) && !PageHeadHuge(page); 470 } 471 472 /* 473 * This takes a head page as parameter and tells if the 474 * tail page reference counting can be skipped. 475 * 476 * For this to be safe, PageSlab and PageHeadHuge must remain true on 477 * any given page where they return true here, until all tail pins 478 * have been released. 479 */ 480 static inline bool compound_tail_refcounted(struct page *page) 481 { 482 VM_BUG_ON_PAGE(!PageHead(page), page); 483 return __compound_tail_refcounted(page); 484 } 485 486 static inline void get_huge_page_tail(struct page *page) 487 { 488 /* 489 * __split_huge_page_refcount() cannot run from under us. 490 */ 491 VM_BUG_ON_PAGE(!PageTail(page), page); 492 VM_BUG_ON_PAGE(page_mapcount(page) < 0, page); 493 VM_BUG_ON_PAGE(atomic_read(&page->_count) != 0, page); 494 if (compound_tail_refcounted(page->first_page)) 495 atomic_inc(&page->_mapcount); 496 } 497 498 extern bool __get_page_tail(struct page *page); 499 500 static inline void get_page(struct page *page) 501 { 502 if (unlikely(PageTail(page))) 503 if (likely(__get_page_tail(page))) 504 return; 505 /* 506 * Getting a normal page or the head of a compound page 507 * requires to already have an elevated page->_count. 508 */ 509 VM_BUG_ON_PAGE(atomic_read(&page->_count) <= 0, page); 510 atomic_inc(&page->_count); 511 } 512 513 static inline struct page *virt_to_head_page(const void *x) 514 { 515 struct page *page = virt_to_page(x); 516 return compound_head(page); 517 } 518 519 /* 520 * Setup the page count before being freed into the page allocator for 521 * the first time (boot or memory hotplug) 522 */ 523 static inline void init_page_count(struct page *page) 524 { 525 atomic_set(&page->_count, 1); 526 } 527 528 /* 529 * PageBuddy() indicate that the page is free and in the buddy system 530 * (see mm/page_alloc.c). 531 * 532 * PAGE_BUDDY_MAPCOUNT_VALUE must be <= -2 but better not too close to 533 * -2 so that an underflow of the page_mapcount() won't be mistaken 534 * for a genuine PAGE_BUDDY_MAPCOUNT_VALUE. -128 can be created very 535 * efficiently by most CPU architectures. 536 */ 537 #define PAGE_BUDDY_MAPCOUNT_VALUE (-128) 538 539 static inline int PageBuddy(struct page *page) 540 { 541 return atomic_read(&page->_mapcount) == PAGE_BUDDY_MAPCOUNT_VALUE; 542 } 543 544 static inline void __SetPageBuddy(struct page *page) 545 { 546 VM_BUG_ON_PAGE(atomic_read(&page->_mapcount) != -1, page); 547 atomic_set(&page->_mapcount, PAGE_BUDDY_MAPCOUNT_VALUE); 548 } 549 550 static inline void __ClearPageBuddy(struct page *page) 551 { 552 VM_BUG_ON_PAGE(!PageBuddy(page), page); 553 atomic_set(&page->_mapcount, -1); 554 } 555 556 void put_page(struct page *page); 557 void put_pages_list(struct list_head *pages); 558 559 void split_page(struct page *page, unsigned int order); 560 int split_free_page(struct page *page); 561 562 /* 563 * Compound pages have a destructor function. Provide a 564 * prototype for that function and accessor functions. 565 * These are _only_ valid on the head of a PG_compound page. 566 */ 567 typedef void compound_page_dtor(struct page *); 568 569 static inline void set_compound_page_dtor(struct page *page, 570 compound_page_dtor *dtor) 571 { 572 page[1].lru.next = (void *)dtor; 573 } 574 575 static inline compound_page_dtor *get_compound_page_dtor(struct page *page) 576 { 577 return (compound_page_dtor *)page[1].lru.next; 578 } 579 580 static inline int compound_order(struct page *page) 581 { 582 if (!PageHead(page)) 583 return 0; 584 return (unsigned long)page[1].lru.prev; 585 } 586 587 static inline void set_compound_order(struct page *page, unsigned long order) 588 { 589 page[1].lru.prev = (void *)order; 590 } 591 592 #ifdef CONFIG_MMU 593 /* 594 * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when 595 * servicing faults for write access. In the normal case, do always want 596 * pte_mkwrite. But get_user_pages can cause write faults for mappings 597 * that do not have writing enabled, when used by access_process_vm. 598 */ 599 static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma) 600 { 601 if (likely(vma->vm_flags & VM_WRITE)) 602 pte = pte_mkwrite(pte); 603 return pte; 604 } 605 606 void do_set_pte(struct vm_area_struct *vma, unsigned long address, 607 struct page *page, pte_t *pte, bool write, bool anon); 608 #endif 609 610 /* 611 * Multiple processes may "see" the same page. E.g. for untouched 612 * mappings of /dev/null, all processes see the same page full of 613 * zeroes, and text pages of executables and shared libraries have 614 * only one copy in memory, at most, normally. 615 * 616 * For the non-reserved pages, page_count(page) denotes a reference count. 617 * page_count() == 0 means the page is free. page->lru is then used for 618 * freelist management in the buddy allocator. 619 * page_count() > 0 means the page has been allocated. 620 * 621 * Pages are allocated by the slab allocator in order to provide memory 622 * to kmalloc and kmem_cache_alloc. In this case, the management of the 623 * page, and the fields in 'struct page' are the responsibility of mm/slab.c 624 * unless a particular usage is carefully commented. (the responsibility of 625 * freeing the kmalloc memory is the caller's, of course). 626 * 627 * A page may be used by anyone else who does a __get_free_page(). 628 * In this case, page_count still tracks the references, and should only 629 * be used through the normal accessor functions. The top bits of page->flags 630 * and page->virtual store page management information, but all other fields 631 * are unused and could be used privately, carefully. The management of this 632 * page is the responsibility of the one who allocated it, and those who have 633 * subsequently been given references to it. 634 * 635 * The other pages (we may call them "pagecache pages") are completely 636 * managed by the Linux memory manager: I/O, buffers, swapping etc. 637 * The following discussion applies only to them. 638 * 639 * A pagecache page contains an opaque `private' member, which belongs to the 640 * page's address_space. Usually, this is the address of a circular list of 641 * the page's disk buffers. PG_private must be set to tell the VM to call 642 * into the filesystem to release these pages. 643 * 644 * A page may belong to an inode's memory mapping. In this case, page->mapping 645 * is the pointer to the inode, and page->index is the file offset of the page, 646 * in units of PAGE_CACHE_SIZE. 647 * 648 * If pagecache pages are not associated with an inode, they are said to be 649 * anonymous pages. These may become associated with the swapcache, and in that 650 * case PG_swapcache is set, and page->private is an offset into the swapcache. 651 * 652 * In either case (swapcache or inode backed), the pagecache itself holds one 653 * reference to the page. Setting PG_private should also increment the 654 * refcount. The each user mapping also has a reference to the page. 655 * 656 * The pagecache pages are stored in a per-mapping radix tree, which is 657 * rooted at mapping->page_tree, and indexed by offset. 658 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space 659 * lists, we instead now tag pages as dirty/writeback in the radix tree. 660 * 661 * All pagecache pages may be subject to I/O: 662 * - inode pages may need to be read from disk, 663 * - inode pages which have been modified and are MAP_SHARED may need 664 * to be written back to the inode on disk, 665 * - anonymous pages (including MAP_PRIVATE file mappings) which have been 666 * modified may need to be swapped out to swap space and (later) to be read 667 * back into memory. 668 */ 669 670 /* 671 * The zone field is never updated after free_area_init_core() 672 * sets it, so none of the operations on it need to be atomic. 673 */ 674 675 /* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_CPUPID] | ... | FLAGS | */ 676 #define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH) 677 #define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH) 678 #define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH) 679 #define LAST_CPUPID_PGOFF (ZONES_PGOFF - LAST_CPUPID_WIDTH) 680 681 /* 682 * Define the bit shifts to access each section. For non-existent 683 * sections we define the shift as 0; that plus a 0 mask ensures 684 * the compiler will optimise away reference to them. 685 */ 686 #define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0)) 687 #define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0)) 688 #define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0)) 689 #define LAST_CPUPID_PGSHIFT (LAST_CPUPID_PGOFF * (LAST_CPUPID_WIDTH != 0)) 690 691 /* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */ 692 #ifdef NODE_NOT_IN_PAGE_FLAGS 693 #define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT) 694 #define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \ 695 SECTIONS_PGOFF : ZONES_PGOFF) 696 #else 697 #define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT) 698 #define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \ 699 NODES_PGOFF : ZONES_PGOFF) 700 #endif 701 702 #define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0)) 703 704 #if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS 705 #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS 706 #endif 707 708 #define ZONES_MASK ((1UL << ZONES_WIDTH) - 1) 709 #define NODES_MASK ((1UL << NODES_WIDTH) - 1) 710 #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1) 711 #define LAST_CPUPID_MASK ((1UL << LAST_CPUPID_SHIFT) - 1) 712 #define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1) 713 714 static inline enum zone_type page_zonenum(const struct page *page) 715 { 716 return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; 717 } 718 719 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) 720 #define SECTION_IN_PAGE_FLAGS 721 #endif 722 723 /* 724 * The identification function is mainly used by the buddy allocator for 725 * determining if two pages could be buddies. We are not really identifying 726 * the zone since we could be using the section number id if we do not have 727 * node id available in page flags. 728 * We only guarantee that it will return the same value for two combinable 729 * pages in a zone. 730 */ 731 static inline int page_zone_id(struct page *page) 732 { 733 return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK; 734 } 735 736 static inline int zone_to_nid(struct zone *zone) 737 { 738 #ifdef CONFIG_NUMA 739 return zone->node; 740 #else 741 return 0; 742 #endif 743 } 744 745 #ifdef NODE_NOT_IN_PAGE_FLAGS 746 extern int page_to_nid(const struct page *page); 747 #else 748 static inline int page_to_nid(const struct page *page) 749 { 750 return (page->flags >> NODES_PGSHIFT) & NODES_MASK; 751 } 752 #endif 753 754 #ifdef CONFIG_NUMA_BALANCING 755 static inline int cpu_pid_to_cpupid(int cpu, int pid) 756 { 757 return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK); 758 } 759 760 static inline int cpupid_to_pid(int cpupid) 761 { 762 return cpupid & LAST__PID_MASK; 763 } 764 765 static inline int cpupid_to_cpu(int cpupid) 766 { 767 return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK; 768 } 769 770 static inline int cpupid_to_nid(int cpupid) 771 { 772 return cpu_to_node(cpupid_to_cpu(cpupid)); 773 } 774 775 static inline bool cpupid_pid_unset(int cpupid) 776 { 777 return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK); 778 } 779 780 static inline bool cpupid_cpu_unset(int cpupid) 781 { 782 return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK); 783 } 784 785 static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid) 786 { 787 return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid); 788 } 789 790 #define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid) 791 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS 792 static inline int page_cpupid_xchg_last(struct page *page, int cpupid) 793 { 794 return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK); 795 } 796 797 static inline int page_cpupid_last(struct page *page) 798 { 799 return page->_last_cpupid; 800 } 801 static inline void page_cpupid_reset_last(struct page *page) 802 { 803 page->_last_cpupid = -1 & LAST_CPUPID_MASK; 804 } 805 #else 806 static inline int page_cpupid_last(struct page *page) 807 { 808 return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK; 809 } 810 811 extern int page_cpupid_xchg_last(struct page *page, int cpupid); 812 813 static inline void page_cpupid_reset_last(struct page *page) 814 { 815 int cpupid = (1 << LAST_CPUPID_SHIFT) - 1; 816 817 page->flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT); 818 page->flags |= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT; 819 } 820 #endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */ 821 #else /* !CONFIG_NUMA_BALANCING */ 822 static inline int page_cpupid_xchg_last(struct page *page, int cpupid) 823 { 824 return page_to_nid(page); /* XXX */ 825 } 826 827 static inline int page_cpupid_last(struct page *page) 828 { 829 return page_to_nid(page); /* XXX */ 830 } 831 832 static inline int cpupid_to_nid(int cpupid) 833 { 834 return -1; 835 } 836 837 static inline int cpupid_to_pid(int cpupid) 838 { 839 return -1; 840 } 841 842 static inline int cpupid_to_cpu(int cpupid) 843 { 844 return -1; 845 } 846 847 static inline int cpu_pid_to_cpupid(int nid, int pid) 848 { 849 return -1; 850 } 851 852 static inline bool cpupid_pid_unset(int cpupid) 853 { 854 return 1; 855 } 856 857 static inline void page_cpupid_reset_last(struct page *page) 858 { 859 } 860 861 static inline bool cpupid_match_pid(struct task_struct *task, int cpupid) 862 { 863 return false; 864 } 865 #endif /* CONFIG_NUMA_BALANCING */ 866 867 static inline struct zone *page_zone(const struct page *page) 868 { 869 return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)]; 870 } 871 872 #ifdef SECTION_IN_PAGE_FLAGS 873 static inline void set_page_section(struct page *page, unsigned long section) 874 { 875 page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT); 876 page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT; 877 } 878 879 static inline unsigned long page_to_section(const struct page *page) 880 { 881 return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; 882 } 883 #endif 884 885 static inline void set_page_zone(struct page *page, enum zone_type zone) 886 { 887 page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); 888 page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; 889 } 890 891 static inline void set_page_node(struct page *page, unsigned long node) 892 { 893 page->flags &= ~(NODES_MASK << NODES_PGSHIFT); 894 page->flags |= (node & NODES_MASK) << NODES_PGSHIFT; 895 } 896 897 static inline void set_page_links(struct page *page, enum zone_type zone, 898 unsigned long node, unsigned long pfn) 899 { 900 set_page_zone(page, zone); 901 set_page_node(page, node); 902 #ifdef SECTION_IN_PAGE_FLAGS 903 set_page_section(page, pfn_to_section_nr(pfn)); 904 #endif 905 } 906 907 /* 908 * Some inline functions in vmstat.h depend on page_zone() 909 */ 910 #include <linux/vmstat.h> 911 912 static __always_inline void *lowmem_page_address(const struct page *page) 913 { 914 return __va(PFN_PHYS(page_to_pfn(page))); 915 } 916 917 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) 918 #define HASHED_PAGE_VIRTUAL 919 #endif 920 921 #if defined(WANT_PAGE_VIRTUAL) 922 static inline void *page_address(const struct page *page) 923 { 924 return page->virtual; 925 } 926 static inline void set_page_address(struct page *page, void *address) 927 { 928 page->virtual = address; 929 } 930 #define page_address_init() do { } while(0) 931 #endif 932 933 #if defined(HASHED_PAGE_VIRTUAL) 934 void *page_address(const struct page *page); 935 void set_page_address(struct page *page, void *virtual); 936 void page_address_init(void); 937 #endif 938 939 #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL) 940 #define page_address(page) lowmem_page_address(page) 941 #define set_page_address(page, address) do { } while(0) 942 #define page_address_init() do { } while(0) 943 #endif 944 945 /* 946 * On an anonymous page mapped into a user virtual memory area, 947 * page->mapping points to its anon_vma, not to a struct address_space; 948 * with the PAGE_MAPPING_ANON bit set to distinguish it. See rmap.h. 949 * 950 * On an anonymous page in a VM_MERGEABLE area, if CONFIG_KSM is enabled, 951 * the PAGE_MAPPING_KSM bit may be set along with the PAGE_MAPPING_ANON bit; 952 * and then page->mapping points, not to an anon_vma, but to a private 953 * structure which KSM associates with that merged page. See ksm.h. 954 * 955 * PAGE_MAPPING_KSM without PAGE_MAPPING_ANON is currently never used. 956 * 957 * Please note that, confusingly, "page_mapping" refers to the inode 958 * address_space which maps the page from disk; whereas "page_mapped" 959 * refers to user virtual address space into which the page is mapped. 960 */ 961 #define PAGE_MAPPING_ANON 1 962 #define PAGE_MAPPING_KSM 2 963 #define PAGE_MAPPING_FLAGS (PAGE_MAPPING_ANON | PAGE_MAPPING_KSM) 964 965 extern struct address_space *page_mapping(struct page *page); 966 967 /* Neutral page->mapping pointer to address_space or anon_vma or other */ 968 static inline void *page_rmapping(struct page *page) 969 { 970 return (void *)((unsigned long)page->mapping & ~PAGE_MAPPING_FLAGS); 971 } 972 973 extern struct address_space *__page_file_mapping(struct page *); 974 975 static inline 976 struct address_space *page_file_mapping(struct page *page) 977 { 978 if (unlikely(PageSwapCache(page))) 979 return __page_file_mapping(page); 980 981 return page->mapping; 982 } 983 984 static inline int PageAnon(struct page *page) 985 { 986 return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0; 987 } 988 989 /* 990 * Return the pagecache index of the passed page. Regular pagecache pages 991 * use ->index whereas swapcache pages use ->private 992 */ 993 static inline pgoff_t page_index(struct page *page) 994 { 995 if (unlikely(PageSwapCache(page))) 996 return page_private(page); 997 return page->index; 998 } 999 1000 extern pgoff_t __page_file_index(struct page *page); 1001 1002 /* 1003 * Return the file index of the page. Regular pagecache pages use ->index 1004 * whereas swapcache pages use swp_offset(->private) 1005 */ 1006 static inline pgoff_t page_file_index(struct page *page) 1007 { 1008 if (unlikely(PageSwapCache(page))) 1009 return __page_file_index(page); 1010 1011 return page->index; 1012 } 1013 1014 /* 1015 * Return true if this page is mapped into pagetables. 1016 */ 1017 static inline int page_mapped(struct page *page) 1018 { 1019 return atomic_read(&(page)->_mapcount) >= 0; 1020 } 1021 1022 /* 1023 * Different kinds of faults, as returned by handle_mm_fault(). 1024 * Used to decide whether a process gets delivered SIGBUS or 1025 * just gets major/minor fault counters bumped up. 1026 */ 1027 1028 #define VM_FAULT_MINOR 0 /* For backwards compat. Remove me quickly. */ 1029 1030 #define VM_FAULT_OOM 0x0001 1031 #define VM_FAULT_SIGBUS 0x0002 1032 #define VM_FAULT_MAJOR 0x0004 1033 #define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */ 1034 #define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */ 1035 #define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index encoded in upper bits */ 1036 1037 #define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */ 1038 #define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */ 1039 #define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */ 1040 #define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back to small */ 1041 1042 #define VM_FAULT_HWPOISON_LARGE_MASK 0xf000 /* encodes hpage index for large hwpoison */ 1043 1044 #define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_HWPOISON | \ 1045 VM_FAULT_FALLBACK | VM_FAULT_HWPOISON_LARGE) 1046 1047 /* Encode hstate index for a hwpoisoned large page */ 1048 #define VM_FAULT_SET_HINDEX(x) ((x) << 12) 1049 #define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf) 1050 1051 /* 1052 * Can be called by the pagefault handler when it gets a VM_FAULT_OOM. 1053 */ 1054 extern void pagefault_out_of_memory(void); 1055 1056 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) 1057 1058 /* 1059 * Flags passed to show_mem() and show_free_areas() to suppress output in 1060 * various contexts. 1061 */ 1062 #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */ 1063 1064 extern void show_free_areas(unsigned int flags); 1065 extern bool skip_free_areas_node(unsigned int flags, int nid); 1066 1067 int shmem_zero_setup(struct vm_area_struct *); 1068 #ifdef CONFIG_SHMEM 1069 bool shmem_mapping(struct address_space *mapping); 1070 #else 1071 static inline bool shmem_mapping(struct address_space *mapping) 1072 { 1073 return false; 1074 } 1075 #endif 1076 1077 extern int can_do_mlock(void); 1078 extern int user_shm_lock(size_t, struct user_struct *); 1079 extern void user_shm_unlock(size_t, struct user_struct *); 1080 1081 /* 1082 * Parameter block passed down to zap_pte_range in exceptional cases. 1083 */ 1084 struct zap_details { 1085 struct vm_area_struct *nonlinear_vma; /* Check page->index if set */ 1086 struct address_space *check_mapping; /* Check page->mapping if set */ 1087 pgoff_t first_index; /* Lowest page->index to unmap */ 1088 pgoff_t last_index; /* Highest page->index to unmap */ 1089 }; 1090 1091 struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, 1092 pte_t pte); 1093 1094 int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address, 1095 unsigned long size); 1096 void zap_page_range(struct vm_area_struct *vma, unsigned long address, 1097 unsigned long size, struct zap_details *); 1098 void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma, 1099 unsigned long start, unsigned long end); 1100 1101 /** 1102 * mm_walk - callbacks for walk_page_range 1103 * @pgd_entry: if set, called for each non-empty PGD (top-level) entry 1104 * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry 1105 * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry 1106 * this handler is required to be able to handle 1107 * pmd_trans_huge() pmds. They may simply choose to 1108 * split_huge_page() instead of handling it explicitly. 1109 * @pte_entry: if set, called for each non-empty PTE (4th-level) entry 1110 * @pte_hole: if set, called for each hole at all levels 1111 * @hugetlb_entry: if set, called for each hugetlb entry 1112 * *Caution*: The caller must hold mmap_sem() if @hugetlb_entry 1113 * is used. 1114 * 1115 * (see walk_page_range for more details) 1116 */ 1117 struct mm_walk { 1118 int (*pgd_entry)(pgd_t *pgd, unsigned long addr, 1119 unsigned long next, struct mm_walk *walk); 1120 int (*pud_entry)(pud_t *pud, unsigned long addr, 1121 unsigned long next, struct mm_walk *walk); 1122 int (*pmd_entry)(pmd_t *pmd, unsigned long addr, 1123 unsigned long next, struct mm_walk *walk); 1124 int (*pte_entry)(pte_t *pte, unsigned long addr, 1125 unsigned long next, struct mm_walk *walk); 1126 int (*pte_hole)(unsigned long addr, unsigned long next, 1127 struct mm_walk *walk); 1128 int (*hugetlb_entry)(pte_t *pte, unsigned long hmask, 1129 unsigned long addr, unsigned long next, 1130 struct mm_walk *walk); 1131 struct mm_struct *mm; 1132 void *private; 1133 }; 1134 1135 int walk_page_range(unsigned long addr, unsigned long end, 1136 struct mm_walk *walk); 1137 void free_pgd_range(struct mmu_gather *tlb, unsigned long addr, 1138 unsigned long end, unsigned long floor, unsigned long ceiling); 1139 int copy_page_range(struct mm_struct *dst, struct mm_struct *src, 1140 struct vm_area_struct *vma); 1141 void unmap_mapping_range(struct address_space *mapping, 1142 loff_t const holebegin, loff_t const holelen, int even_cows); 1143 int follow_pfn(struct vm_area_struct *vma, unsigned long address, 1144 unsigned long *pfn); 1145 int follow_phys(struct vm_area_struct *vma, unsigned long address, 1146 unsigned int flags, unsigned long *prot, resource_size_t *phys); 1147 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr, 1148 void *buf, int len, int write); 1149 1150 static inline void unmap_shared_mapping_range(struct address_space *mapping, 1151 loff_t const holebegin, loff_t const holelen) 1152 { 1153 unmap_mapping_range(mapping, holebegin, holelen, 0); 1154 } 1155 1156 extern void truncate_pagecache(struct inode *inode, loff_t new); 1157 extern void truncate_setsize(struct inode *inode, loff_t newsize); 1158 void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end); 1159 int truncate_inode_page(struct address_space *mapping, struct page *page); 1160 int generic_error_remove_page(struct address_space *mapping, struct page *page); 1161 int invalidate_inode_page(struct page *page); 1162 1163 #ifdef CONFIG_MMU 1164 extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, 1165 unsigned long address, unsigned int flags); 1166 extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm, 1167 unsigned long address, unsigned int fault_flags); 1168 #else 1169 static inline int handle_mm_fault(struct mm_struct *mm, 1170 struct vm_area_struct *vma, unsigned long address, 1171 unsigned int flags) 1172 { 1173 /* should never happen if there's no MMU */ 1174 BUG(); 1175 return VM_FAULT_SIGBUS; 1176 } 1177 static inline int fixup_user_fault(struct task_struct *tsk, 1178 struct mm_struct *mm, unsigned long address, 1179 unsigned int fault_flags) 1180 { 1181 /* should never happen if there's no MMU */ 1182 BUG(); 1183 return -EFAULT; 1184 } 1185 #endif 1186 1187 extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write); 1188 extern int access_remote_vm(struct mm_struct *mm, unsigned long addr, 1189 void *buf, int len, int write); 1190 1191 long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, 1192 unsigned long start, unsigned long nr_pages, 1193 unsigned int foll_flags, struct page **pages, 1194 struct vm_area_struct **vmas, int *nonblocking); 1195 long get_user_pages(struct task_struct *tsk, struct mm_struct *mm, 1196 unsigned long start, unsigned long nr_pages, 1197 int write, int force, struct page **pages, 1198 struct vm_area_struct **vmas); 1199 int get_user_pages_fast(unsigned long start, int nr_pages, int write, 1200 struct page **pages); 1201 struct kvec; 1202 int get_kernel_pages(const struct kvec *iov, int nr_pages, int write, 1203 struct page **pages); 1204 int get_kernel_page(unsigned long start, int write, struct page **pages); 1205 struct page *get_dump_page(unsigned long addr); 1206 1207 extern int try_to_release_page(struct page * page, gfp_t gfp_mask); 1208 extern void do_invalidatepage(struct page *page, unsigned int offset, 1209 unsigned int length); 1210 1211 int __set_page_dirty_nobuffers(struct page *page); 1212 int __set_page_dirty_no_writeback(struct page *page); 1213 int redirty_page_for_writepage(struct writeback_control *wbc, 1214 struct page *page); 1215 void account_page_dirtied(struct page *page, struct address_space *mapping); 1216 void account_page_writeback(struct page *page); 1217 int set_page_dirty(struct page *page); 1218 int set_page_dirty_lock(struct page *page); 1219 int clear_page_dirty_for_io(struct page *page); 1220 int get_cmdline(struct task_struct *task, char *buffer, int buflen); 1221 1222 /* Is the vma a continuation of the stack vma above it? */ 1223 static inline int vma_growsdown(struct vm_area_struct *vma, unsigned long addr) 1224 { 1225 return vma && (vma->vm_end == addr) && (vma->vm_flags & VM_GROWSDOWN); 1226 } 1227 1228 static inline int stack_guard_page_start(struct vm_area_struct *vma, 1229 unsigned long addr) 1230 { 1231 return (vma->vm_flags & VM_GROWSDOWN) && 1232 (vma->vm_start == addr) && 1233 !vma_growsdown(vma->vm_prev, addr); 1234 } 1235 1236 /* Is the vma a continuation of the stack vma below it? */ 1237 static inline int vma_growsup(struct vm_area_struct *vma, unsigned long addr) 1238 { 1239 return vma && (vma->vm_start == addr) && (vma->vm_flags & VM_GROWSUP); 1240 } 1241 1242 static inline int stack_guard_page_end(struct vm_area_struct *vma, 1243 unsigned long addr) 1244 { 1245 return (vma->vm_flags & VM_GROWSUP) && 1246 (vma->vm_end == addr) && 1247 !vma_growsup(vma->vm_next, addr); 1248 } 1249 1250 extern pid_t 1251 vm_is_stack(struct task_struct *task, struct vm_area_struct *vma, int in_group); 1252 1253 extern unsigned long move_page_tables(struct vm_area_struct *vma, 1254 unsigned long old_addr, struct vm_area_struct *new_vma, 1255 unsigned long new_addr, unsigned long len, 1256 bool need_rmap_locks); 1257 extern unsigned long change_protection(struct vm_area_struct *vma, unsigned long start, 1258 unsigned long end, pgprot_t newprot, 1259 int dirty_accountable, int prot_numa); 1260 extern int mprotect_fixup(struct vm_area_struct *vma, 1261 struct vm_area_struct **pprev, unsigned long start, 1262 unsigned long end, unsigned long newflags); 1263 1264 /* 1265 * doesn't attempt to fault and will return short. 1266 */ 1267 int __get_user_pages_fast(unsigned long start, int nr_pages, int write, 1268 struct page **pages); 1269 /* 1270 * per-process(per-mm_struct) statistics. 1271 */ 1272 static inline unsigned long get_mm_counter(struct mm_struct *mm, int member) 1273 { 1274 long val = atomic_long_read(&mm->rss_stat.count[member]); 1275 1276 #ifdef SPLIT_RSS_COUNTING 1277 /* 1278 * counter is updated in asynchronous manner and may go to minus. 1279 * But it's never be expected number for users. 1280 */ 1281 if (val < 0) 1282 val = 0; 1283 #endif 1284 return (unsigned long)val; 1285 } 1286 1287 static inline void add_mm_counter(struct mm_struct *mm, int member, long value) 1288 { 1289 atomic_long_add(value, &mm->rss_stat.count[member]); 1290 } 1291 1292 static inline void inc_mm_counter(struct mm_struct *mm, int member) 1293 { 1294 atomic_long_inc(&mm->rss_stat.count[member]); 1295 } 1296 1297 static inline void dec_mm_counter(struct mm_struct *mm, int member) 1298 { 1299 atomic_long_dec(&mm->rss_stat.count[member]); 1300 } 1301 1302 static inline unsigned long get_mm_rss(struct mm_struct *mm) 1303 { 1304 return get_mm_counter(mm, MM_FILEPAGES) + 1305 get_mm_counter(mm, MM_ANONPAGES); 1306 } 1307 1308 static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm) 1309 { 1310 return max(mm->hiwater_rss, get_mm_rss(mm)); 1311 } 1312 1313 static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm) 1314 { 1315 return max(mm->hiwater_vm, mm->total_vm); 1316 } 1317 1318 static inline void update_hiwater_rss(struct mm_struct *mm) 1319 { 1320 unsigned long _rss = get_mm_rss(mm); 1321 1322 if ((mm)->hiwater_rss < _rss) 1323 (mm)->hiwater_rss = _rss; 1324 } 1325 1326 static inline void update_hiwater_vm(struct mm_struct *mm) 1327 { 1328 if (mm->hiwater_vm < mm->total_vm) 1329 mm->hiwater_vm = mm->total_vm; 1330 } 1331 1332 static inline void setmax_mm_hiwater_rss(unsigned long *maxrss, 1333 struct mm_struct *mm) 1334 { 1335 unsigned long hiwater_rss = get_mm_hiwater_rss(mm); 1336 1337 if (*maxrss < hiwater_rss) 1338 *maxrss = hiwater_rss; 1339 } 1340 1341 #if defined(SPLIT_RSS_COUNTING) 1342 void sync_mm_rss(struct mm_struct *mm); 1343 #else 1344 static inline void sync_mm_rss(struct mm_struct *mm) 1345 { 1346 } 1347 #endif 1348 1349 int vma_wants_writenotify(struct vm_area_struct *vma); 1350 1351 extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr, 1352 spinlock_t **ptl); 1353 static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, 1354 spinlock_t **ptl) 1355 { 1356 pte_t *ptep; 1357 __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl)); 1358 return ptep; 1359 } 1360 1361 #ifdef __PAGETABLE_PUD_FOLDED 1362 static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, 1363 unsigned long address) 1364 { 1365 return 0; 1366 } 1367 #else 1368 int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); 1369 #endif 1370 1371 #ifdef __PAGETABLE_PMD_FOLDED 1372 static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud, 1373 unsigned long address) 1374 { 1375 return 0; 1376 } 1377 #else 1378 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); 1379 #endif 1380 1381 int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, 1382 pmd_t *pmd, unsigned long address); 1383 int __pte_alloc_kernel(pmd_t *pmd, unsigned long address); 1384 1385 /* 1386 * The following ifdef needed to get the 4level-fixup.h header to work. 1387 * Remove it when 4level-fixup.h has been removed. 1388 */ 1389 #if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK) 1390 static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address) 1391 { 1392 return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))? 1393 NULL: pud_offset(pgd, address); 1394 } 1395 1396 static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) 1397 { 1398 return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))? 1399 NULL: pmd_offset(pud, address); 1400 } 1401 #endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */ 1402 1403 #if USE_SPLIT_PTE_PTLOCKS 1404 #if ALLOC_SPLIT_PTLOCKS 1405 void __init ptlock_cache_init(void); 1406 extern bool ptlock_alloc(struct page *page); 1407 extern void ptlock_free(struct page *page); 1408 1409 static inline spinlock_t *ptlock_ptr(struct page *page) 1410 { 1411 return page->ptl; 1412 } 1413 #else /* ALLOC_SPLIT_PTLOCKS */ 1414 static inline void ptlock_cache_init(void) 1415 { 1416 } 1417 1418 static inline bool ptlock_alloc(struct page *page) 1419 { 1420 return true; 1421 } 1422 1423 static inline void ptlock_free(struct page *page) 1424 { 1425 } 1426 1427 static inline spinlock_t *ptlock_ptr(struct page *page) 1428 { 1429 return &page->ptl; 1430 } 1431 #endif /* ALLOC_SPLIT_PTLOCKS */ 1432 1433 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd) 1434 { 1435 return ptlock_ptr(pmd_page(*pmd)); 1436 } 1437 1438 static inline bool ptlock_init(struct page *page) 1439 { 1440 /* 1441 * prep_new_page() initialize page->private (and therefore page->ptl) 1442 * with 0. Make sure nobody took it in use in between. 1443 * 1444 * It can happen if arch try to use slab for page table allocation: 1445 * slab code uses page->slab_cache and page->first_page (for tail 1446 * pages), which share storage with page->ptl. 1447 */ 1448 VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page); 1449 if (!ptlock_alloc(page)) 1450 return false; 1451 spin_lock_init(ptlock_ptr(page)); 1452 return true; 1453 } 1454 1455 /* Reset page->mapping so free_pages_check won't complain. */ 1456 static inline void pte_lock_deinit(struct page *page) 1457 { 1458 page->mapping = NULL; 1459 ptlock_free(page); 1460 } 1461 1462 #else /* !USE_SPLIT_PTE_PTLOCKS */ 1463 /* 1464 * We use mm->page_table_lock to guard all pagetable pages of the mm. 1465 */ 1466 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd) 1467 { 1468 return &mm->page_table_lock; 1469 } 1470 static inline void ptlock_cache_init(void) {} 1471 static inline bool ptlock_init(struct page *page) { return true; } 1472 static inline void pte_lock_deinit(struct page *page) {} 1473 #endif /* USE_SPLIT_PTE_PTLOCKS */ 1474 1475 static inline void pgtable_init(void) 1476 { 1477 ptlock_cache_init(); 1478 pgtable_cache_init(); 1479 } 1480 1481 static inline bool pgtable_page_ctor(struct page *page) 1482 { 1483 inc_zone_page_state(page, NR_PAGETABLE); 1484 return ptlock_init(page); 1485 } 1486 1487 static inline void pgtable_page_dtor(struct page *page) 1488 { 1489 pte_lock_deinit(page); 1490 dec_zone_page_state(page, NR_PAGETABLE); 1491 } 1492 1493 #define pte_offset_map_lock(mm, pmd, address, ptlp) \ 1494 ({ \ 1495 spinlock_t *__ptl = pte_lockptr(mm, pmd); \ 1496 pte_t *__pte = pte_offset_map(pmd, address); \ 1497 *(ptlp) = __ptl; \ 1498 spin_lock(__ptl); \ 1499 __pte; \ 1500 }) 1501 1502 #define pte_unmap_unlock(pte, ptl) do { \ 1503 spin_unlock(ptl); \ 1504 pte_unmap(pte); \ 1505 } while (0) 1506 1507 #define pte_alloc_map(mm, vma, pmd, address) \ 1508 ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, vma, \ 1509 pmd, address))? \ 1510 NULL: pte_offset_map(pmd, address)) 1511 1512 #define pte_alloc_map_lock(mm, pmd, address, ptlp) \ 1513 ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, NULL, \ 1514 pmd, address))? \ 1515 NULL: pte_offset_map_lock(mm, pmd, address, ptlp)) 1516 1517 #define pte_alloc_kernel(pmd, address) \ 1518 ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd, address))? \ 1519 NULL: pte_offset_kernel(pmd, address)) 1520 1521 #if USE_SPLIT_PMD_PTLOCKS 1522 1523 static struct page *pmd_to_page(pmd_t *pmd) 1524 { 1525 unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); 1526 return virt_to_page((void *)((unsigned long) pmd & mask)); 1527 } 1528 1529 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) 1530 { 1531 return ptlock_ptr(pmd_to_page(pmd)); 1532 } 1533 1534 static inline bool pgtable_pmd_page_ctor(struct page *page) 1535 { 1536 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1537 page->pmd_huge_pte = NULL; 1538 #endif 1539 return ptlock_init(page); 1540 } 1541 1542 static inline void pgtable_pmd_page_dtor(struct page *page) 1543 { 1544 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1545 VM_BUG_ON_PAGE(page->pmd_huge_pte, page); 1546 #endif 1547 ptlock_free(page); 1548 } 1549 1550 #define pmd_huge_pte(mm, pmd) (pmd_to_page(pmd)->pmd_huge_pte) 1551 1552 #else 1553 1554 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) 1555 { 1556 return &mm->page_table_lock; 1557 } 1558 1559 static inline bool pgtable_pmd_page_ctor(struct page *page) { return true; } 1560 static inline void pgtable_pmd_page_dtor(struct page *page) {} 1561 1562 #define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte) 1563 1564 #endif 1565 1566 static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd) 1567 { 1568 spinlock_t *ptl = pmd_lockptr(mm, pmd); 1569 spin_lock(ptl); 1570 return ptl; 1571 } 1572 1573 extern void free_area_init(unsigned long * zones_size); 1574 extern void free_area_init_node(int nid, unsigned long * zones_size, 1575 unsigned long zone_start_pfn, unsigned long *zholes_size); 1576 extern void free_initmem(void); 1577 1578 /* 1579 * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK) 1580 * into the buddy system. The freed pages will be poisoned with pattern 1581 * "poison" if it's within range [0, UCHAR_MAX]. 1582 * Return pages freed into the buddy system. 1583 */ 1584 extern unsigned long free_reserved_area(void *start, void *end, 1585 int poison, char *s); 1586 1587 #ifdef CONFIG_HIGHMEM 1588 /* 1589 * Free a highmem page into the buddy system, adjusting totalhigh_pages 1590 * and totalram_pages. 1591 */ 1592 extern void free_highmem_page(struct page *page); 1593 #endif 1594 1595 extern void adjust_managed_page_count(struct page *page, long count); 1596 extern void mem_init_print_info(const char *str); 1597 1598 /* Free the reserved page into the buddy system, so it gets managed. */ 1599 static inline void __free_reserved_page(struct page *page) 1600 { 1601 ClearPageReserved(page); 1602 init_page_count(page); 1603 __free_page(page); 1604 } 1605 1606 static inline void free_reserved_page(struct page *page) 1607 { 1608 __free_reserved_page(page); 1609 adjust_managed_page_count(page, 1); 1610 } 1611 1612 static inline void mark_page_reserved(struct page *page) 1613 { 1614 SetPageReserved(page); 1615 adjust_managed_page_count(page, -1); 1616 } 1617 1618 /* 1619 * Default method to free all the __init memory into the buddy system. 1620 * The freed pages will be poisoned with pattern "poison" if it's within 1621 * range [0, UCHAR_MAX]. 1622 * Return pages freed into the buddy system. 1623 */ 1624 static inline unsigned long free_initmem_default(int poison) 1625 { 1626 extern char __init_begin[], __init_end[]; 1627 1628 return free_reserved_area(&__init_begin, &__init_end, 1629 poison, "unused kernel"); 1630 } 1631 1632 static inline unsigned long get_num_physpages(void) 1633 { 1634 int nid; 1635 unsigned long phys_pages = 0; 1636 1637 for_each_online_node(nid) 1638 phys_pages += node_present_pages(nid); 1639 1640 return phys_pages; 1641 } 1642 1643 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP 1644 /* 1645 * With CONFIG_HAVE_MEMBLOCK_NODE_MAP set, an architecture may initialise its 1646 * zones, allocate the backing mem_map and account for memory holes in a more 1647 * architecture independent manner. This is a substitute for creating the 1648 * zone_sizes[] and zholes_size[] arrays and passing them to 1649 * free_area_init_node() 1650 * 1651 * An architecture is expected to register range of page frames backed by 1652 * physical memory with memblock_add[_node]() before calling 1653 * free_area_init_nodes() passing in the PFN each zone ends at. At a basic 1654 * usage, an architecture is expected to do something like 1655 * 1656 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn, 1657 * max_highmem_pfn}; 1658 * for_each_valid_physical_page_range() 1659 * memblock_add_node(base, size, nid) 1660 * free_area_init_nodes(max_zone_pfns); 1661 * 1662 * free_bootmem_with_active_regions() calls free_bootmem_node() for each 1663 * registered physical page range. Similarly 1664 * sparse_memory_present_with_active_regions() calls memory_present() for 1665 * each range when SPARSEMEM is enabled. 1666 * 1667 * See mm/page_alloc.c for more information on each function exposed by 1668 * CONFIG_HAVE_MEMBLOCK_NODE_MAP. 1669 */ 1670 extern void free_area_init_nodes(unsigned long *max_zone_pfn); 1671 unsigned long node_map_pfn_alignment(void); 1672 unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn, 1673 unsigned long end_pfn); 1674 extern unsigned long absent_pages_in_range(unsigned long start_pfn, 1675 unsigned long end_pfn); 1676 extern void get_pfn_range_for_nid(unsigned int nid, 1677 unsigned long *start_pfn, unsigned long *end_pfn); 1678 extern unsigned long find_min_pfn_with_active_regions(void); 1679 extern void free_bootmem_with_active_regions(int nid, 1680 unsigned long max_low_pfn); 1681 extern void sparse_memory_present_with_active_regions(int nid); 1682 1683 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ 1684 1685 #if !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) && \ 1686 !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) 1687 static inline int __early_pfn_to_nid(unsigned long pfn) 1688 { 1689 return 0; 1690 } 1691 #else 1692 /* please see mm/page_alloc.c */ 1693 extern int __meminit early_pfn_to_nid(unsigned long pfn); 1694 /* there is a per-arch backend function. */ 1695 extern int __meminit __early_pfn_to_nid(unsigned long pfn); 1696 #endif 1697 1698 extern void set_dma_reserve(unsigned long new_dma_reserve); 1699 extern void memmap_init_zone(unsigned long, int, unsigned long, 1700 unsigned long, enum memmap_context); 1701 extern void setup_per_zone_wmarks(void); 1702 extern int __meminit init_per_zone_wmark_min(void); 1703 extern void mem_init(void); 1704 extern void __init mmap_init(void); 1705 extern void show_mem(unsigned int flags); 1706 extern void si_meminfo(struct sysinfo * val); 1707 extern void si_meminfo_node(struct sysinfo *val, int nid); 1708 1709 extern __printf(3, 4) 1710 void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...); 1711 1712 extern void setup_per_cpu_pageset(void); 1713 1714 extern void zone_pcp_update(struct zone *zone); 1715 extern void zone_pcp_reset(struct zone *zone); 1716 1717 /* page_alloc.c */ 1718 extern int min_free_kbytes; 1719 1720 /* nommu.c */ 1721 extern atomic_long_t mmap_pages_allocated; 1722 extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t); 1723 1724 /* interval_tree.c */ 1725 void vma_interval_tree_insert(struct vm_area_struct *node, 1726 struct rb_root *root); 1727 void vma_interval_tree_insert_after(struct vm_area_struct *node, 1728 struct vm_area_struct *prev, 1729 struct rb_root *root); 1730 void vma_interval_tree_remove(struct vm_area_struct *node, 1731 struct rb_root *root); 1732 struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root *root, 1733 unsigned long start, unsigned long last); 1734 struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node, 1735 unsigned long start, unsigned long last); 1736 1737 #define vma_interval_tree_foreach(vma, root, start, last) \ 1738 for (vma = vma_interval_tree_iter_first(root, start, last); \ 1739 vma; vma = vma_interval_tree_iter_next(vma, start, last)) 1740 1741 static inline void vma_nonlinear_insert(struct vm_area_struct *vma, 1742 struct list_head *list) 1743 { 1744 list_add_tail(&vma->shared.nonlinear, list); 1745 } 1746 1747 void anon_vma_interval_tree_insert(struct anon_vma_chain *node, 1748 struct rb_root *root); 1749 void anon_vma_interval_tree_remove(struct anon_vma_chain *node, 1750 struct rb_root *root); 1751 struct anon_vma_chain *anon_vma_interval_tree_iter_first( 1752 struct rb_root *root, unsigned long start, unsigned long last); 1753 struct anon_vma_chain *anon_vma_interval_tree_iter_next( 1754 struct anon_vma_chain *node, unsigned long start, unsigned long last); 1755 #ifdef CONFIG_DEBUG_VM_RB 1756 void anon_vma_interval_tree_verify(struct anon_vma_chain *node); 1757 #endif 1758 1759 #define anon_vma_interval_tree_foreach(avc, root, start, last) \ 1760 for (avc = anon_vma_interval_tree_iter_first(root, start, last); \ 1761 avc; avc = anon_vma_interval_tree_iter_next(avc, start, last)) 1762 1763 /* mmap.c */ 1764 extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin); 1765 extern int vma_adjust(struct vm_area_struct *vma, unsigned long start, 1766 unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert); 1767 extern struct vm_area_struct *vma_merge(struct mm_struct *, 1768 struct vm_area_struct *prev, unsigned long addr, unsigned long end, 1769 unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t, 1770 struct mempolicy *); 1771 extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *); 1772 extern int split_vma(struct mm_struct *, 1773 struct vm_area_struct *, unsigned long addr, int new_below); 1774 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *); 1775 extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *, 1776 struct rb_node **, struct rb_node *); 1777 extern void unlink_file_vma(struct vm_area_struct *); 1778 extern struct vm_area_struct *copy_vma(struct vm_area_struct **, 1779 unsigned long addr, unsigned long len, pgoff_t pgoff, 1780 bool *need_rmap_locks); 1781 extern void exit_mmap(struct mm_struct *); 1782 1783 extern int mm_take_all_locks(struct mm_struct *mm); 1784 extern void mm_drop_all_locks(struct mm_struct *mm); 1785 1786 extern void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file); 1787 extern struct file *get_mm_exe_file(struct mm_struct *mm); 1788 1789 extern int may_expand_vm(struct mm_struct *mm, unsigned long npages); 1790 extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm, 1791 unsigned long addr, unsigned long len, 1792 unsigned long flags, 1793 const struct vm_special_mapping *spec); 1794 /* This is an obsolete alternative to _install_special_mapping. */ 1795 extern int install_special_mapping(struct mm_struct *mm, 1796 unsigned long addr, unsigned long len, 1797 unsigned long flags, struct page **pages); 1798 1799 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); 1800 1801 extern unsigned long mmap_region(struct file *file, unsigned long addr, 1802 unsigned long len, vm_flags_t vm_flags, unsigned long pgoff); 1803 extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, 1804 unsigned long len, unsigned long prot, unsigned long flags, 1805 unsigned long pgoff, unsigned long *populate); 1806 extern int do_munmap(struct mm_struct *, unsigned long, size_t); 1807 1808 #ifdef CONFIG_MMU 1809 extern int __mm_populate(unsigned long addr, unsigned long len, 1810 int ignore_errors); 1811 static inline void mm_populate(unsigned long addr, unsigned long len) 1812 { 1813 /* Ignore errors */ 1814 (void) __mm_populate(addr, len, 1); 1815 } 1816 #else 1817 static inline void mm_populate(unsigned long addr, unsigned long len) {} 1818 #endif 1819 1820 /* These take the mm semaphore themselves */ 1821 extern unsigned long vm_brk(unsigned long, unsigned long); 1822 extern int vm_munmap(unsigned long, size_t); 1823 extern unsigned long vm_mmap(struct file *, unsigned long, 1824 unsigned long, unsigned long, 1825 unsigned long, unsigned long); 1826 1827 struct vm_unmapped_area_info { 1828 #define VM_UNMAPPED_AREA_TOPDOWN 1 1829 unsigned long flags; 1830 unsigned long length; 1831 unsigned long low_limit; 1832 unsigned long high_limit; 1833 unsigned long align_mask; 1834 unsigned long align_offset; 1835 }; 1836 1837 extern unsigned long unmapped_area(struct vm_unmapped_area_info *info); 1838 extern unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info); 1839 1840 /* 1841 * Search for an unmapped address range. 1842 * 1843 * We are looking for a range that: 1844 * - does not intersect with any VMA; 1845 * - is contained within the [low_limit, high_limit) interval; 1846 * - is at least the desired size. 1847 * - satisfies (begin_addr & align_mask) == (align_offset & align_mask) 1848 */ 1849 static inline unsigned long 1850 vm_unmapped_area(struct vm_unmapped_area_info *info) 1851 { 1852 if (!(info->flags & VM_UNMAPPED_AREA_TOPDOWN)) 1853 return unmapped_area(info); 1854 else 1855 return unmapped_area_topdown(info); 1856 } 1857 1858 /* truncate.c */ 1859 extern void truncate_inode_pages(struct address_space *, loff_t); 1860 extern void truncate_inode_pages_range(struct address_space *, 1861 loff_t lstart, loff_t lend); 1862 extern void truncate_inode_pages_final(struct address_space *); 1863 1864 /* generic vm_area_ops exported for stackable file systems */ 1865 extern int filemap_fault(struct vm_area_struct *, struct vm_fault *); 1866 extern void filemap_map_pages(struct vm_area_struct *vma, struct vm_fault *vmf); 1867 extern int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf); 1868 1869 /* mm/page-writeback.c */ 1870 int write_one_page(struct page *page, int wait); 1871 void task_dirty_inc(struct task_struct *tsk); 1872 1873 /* readahead.c */ 1874 #define VM_MAX_READAHEAD 128 /* kbytes */ 1875 #define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */ 1876 1877 int force_page_cache_readahead(struct address_space *mapping, struct file *filp, 1878 pgoff_t offset, unsigned long nr_to_read); 1879 1880 void page_cache_sync_readahead(struct address_space *mapping, 1881 struct file_ra_state *ra, 1882 struct file *filp, 1883 pgoff_t offset, 1884 unsigned long size); 1885 1886 void page_cache_async_readahead(struct address_space *mapping, 1887 struct file_ra_state *ra, 1888 struct file *filp, 1889 struct page *pg, 1890 pgoff_t offset, 1891 unsigned long size); 1892 1893 unsigned long max_sane_readahead(unsigned long nr); 1894 1895 /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */ 1896 extern int expand_stack(struct vm_area_struct *vma, unsigned long address); 1897 1898 /* CONFIG_STACK_GROWSUP still needs to to grow downwards at some places */ 1899 extern int expand_downwards(struct vm_area_struct *vma, 1900 unsigned long address); 1901 #if VM_GROWSUP 1902 extern int expand_upwards(struct vm_area_struct *vma, unsigned long address); 1903 #else 1904 #define expand_upwards(vma, address) do { } while (0) 1905 #endif 1906 1907 /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */ 1908 extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr); 1909 extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr, 1910 struct vm_area_struct **pprev); 1911 1912 /* Look up the first VMA which intersects the interval start_addr..end_addr-1, 1913 NULL if none. Assume start_addr < end_addr. */ 1914 static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr) 1915 { 1916 struct vm_area_struct * vma = find_vma(mm,start_addr); 1917 1918 if (vma && end_addr <= vma->vm_start) 1919 vma = NULL; 1920 return vma; 1921 } 1922 1923 static inline unsigned long vma_pages(struct vm_area_struct *vma) 1924 { 1925 return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; 1926 } 1927 1928 /* Look up the first VMA which exactly match the interval vm_start ... vm_end */ 1929 static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm, 1930 unsigned long vm_start, unsigned long vm_end) 1931 { 1932 struct vm_area_struct *vma = find_vma(mm, vm_start); 1933 1934 if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end)) 1935 vma = NULL; 1936 1937 return vma; 1938 } 1939 1940 #ifdef CONFIG_MMU 1941 pgprot_t vm_get_page_prot(unsigned long vm_flags); 1942 #else 1943 static inline pgprot_t vm_get_page_prot(unsigned long vm_flags) 1944 { 1945 return __pgprot(0); 1946 } 1947 #endif 1948 1949 #ifdef CONFIG_NUMA_BALANCING 1950 unsigned long change_prot_numa(struct vm_area_struct *vma, 1951 unsigned long start, unsigned long end); 1952 #endif 1953 1954 struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr); 1955 int remap_pfn_range(struct vm_area_struct *, unsigned long addr, 1956 unsigned long pfn, unsigned long size, pgprot_t); 1957 int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *); 1958 int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr, 1959 unsigned long pfn); 1960 int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr, 1961 unsigned long pfn); 1962 int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len); 1963 1964 1965 struct page *follow_page_mask(struct vm_area_struct *vma, 1966 unsigned long address, unsigned int foll_flags, 1967 unsigned int *page_mask); 1968 1969 static inline struct page *follow_page(struct vm_area_struct *vma, 1970 unsigned long address, unsigned int foll_flags) 1971 { 1972 unsigned int unused_page_mask; 1973 return follow_page_mask(vma, address, foll_flags, &unused_page_mask); 1974 } 1975 1976 #define FOLL_WRITE 0x01 /* check pte is writable */ 1977 #define FOLL_TOUCH 0x02 /* mark page accessed */ 1978 #define FOLL_GET 0x04 /* do get_page on page */ 1979 #define FOLL_DUMP 0x08 /* give error on hole if it would be zero */ 1980 #define FOLL_FORCE 0x10 /* get_user_pages read/write w/o permission */ 1981 #define FOLL_NOWAIT 0x20 /* if a disk transfer is needed, start the IO 1982 * and return without waiting upon it */ 1983 #define FOLL_MLOCK 0x40 /* mark page as mlocked */ 1984 #define FOLL_SPLIT 0x80 /* don't return transhuge pages, split them */ 1985 #define FOLL_HWPOISON 0x100 /* check page is hwpoisoned */ 1986 #define FOLL_NUMA 0x200 /* force NUMA hinting page fault */ 1987 #define FOLL_MIGRATION 0x400 /* wait for page to replace migration entry */ 1988 1989 typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr, 1990 void *data); 1991 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address, 1992 unsigned long size, pte_fn_t fn, void *data); 1993 1994 #ifdef CONFIG_PROC_FS 1995 void vm_stat_account(struct mm_struct *, unsigned long, struct file *, long); 1996 #else 1997 static inline void vm_stat_account(struct mm_struct *mm, 1998 unsigned long flags, struct file *file, long pages) 1999 { 2000 mm->total_vm += pages; 2001 } 2002 #endif /* CONFIG_PROC_FS */ 2003 2004 #ifdef CONFIG_DEBUG_PAGEALLOC 2005 extern void kernel_map_pages(struct page *page, int numpages, int enable); 2006 #ifdef CONFIG_HIBERNATION 2007 extern bool kernel_page_present(struct page *page); 2008 #endif /* CONFIG_HIBERNATION */ 2009 #else 2010 static inline void 2011 kernel_map_pages(struct page *page, int numpages, int enable) {} 2012 #ifdef CONFIG_HIBERNATION 2013 static inline bool kernel_page_present(struct page *page) { return true; } 2014 #endif /* CONFIG_HIBERNATION */ 2015 #endif 2016 2017 extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm); 2018 #ifdef __HAVE_ARCH_GATE_AREA 2019 int in_gate_area_no_mm(unsigned long addr); 2020 int in_gate_area(struct mm_struct *mm, unsigned long addr); 2021 #else 2022 int in_gate_area_no_mm(unsigned long addr); 2023 #define in_gate_area(mm, addr) ({(void)mm; in_gate_area_no_mm(addr);}) 2024 #endif /* __HAVE_ARCH_GATE_AREA */ 2025 2026 #ifdef CONFIG_SYSCTL 2027 extern int sysctl_drop_caches; 2028 int drop_caches_sysctl_handler(struct ctl_table *, int, 2029 void __user *, size_t *, loff_t *); 2030 #endif 2031 2032 unsigned long shrink_slab(struct shrink_control *shrink, 2033 unsigned long nr_pages_scanned, 2034 unsigned long lru_pages); 2035 2036 #ifndef CONFIG_MMU 2037 #define randomize_va_space 0 2038 #else 2039 extern int randomize_va_space; 2040 #endif 2041 2042 const char * arch_vma_name(struct vm_area_struct *vma); 2043 void print_vma_addr(char *prefix, unsigned long rip); 2044 2045 void sparse_mem_maps_populate_node(struct page **map_map, 2046 unsigned long pnum_begin, 2047 unsigned long pnum_end, 2048 unsigned long map_count, 2049 int nodeid); 2050 2051 struct page *sparse_mem_map_populate(unsigned long pnum, int nid); 2052 pgd_t *vmemmap_pgd_populate(unsigned long addr, int node); 2053 pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node); 2054 pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node); 2055 pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node); 2056 void *vmemmap_alloc_block(unsigned long size, int node); 2057 void *vmemmap_alloc_block_buf(unsigned long size, int node); 2058 void vmemmap_verify(pte_t *, int, unsigned long, unsigned long); 2059 int vmemmap_populate_basepages(unsigned long start, unsigned long end, 2060 int node); 2061 int vmemmap_populate(unsigned long start, unsigned long end, int node); 2062 void vmemmap_populate_print_last(void); 2063 #ifdef CONFIG_MEMORY_HOTPLUG 2064 void vmemmap_free(unsigned long start, unsigned long end); 2065 #endif 2066 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map, 2067 unsigned long size); 2068 2069 enum mf_flags { 2070 MF_COUNT_INCREASED = 1 << 0, 2071 MF_ACTION_REQUIRED = 1 << 1, 2072 MF_MUST_KILL = 1 << 2, 2073 MF_SOFT_OFFLINE = 1 << 3, 2074 }; 2075 extern int memory_failure(unsigned long pfn, int trapno, int flags); 2076 extern void memory_failure_queue(unsigned long pfn, int trapno, int flags); 2077 extern int unpoison_memory(unsigned long pfn); 2078 extern int sysctl_memory_failure_early_kill; 2079 extern int sysctl_memory_failure_recovery; 2080 extern void shake_page(struct page *p, int access); 2081 extern atomic_long_t num_poisoned_pages; 2082 extern int soft_offline_page(struct page *page, int flags); 2083 2084 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS) 2085 extern void clear_huge_page(struct page *page, 2086 unsigned long addr, 2087 unsigned int pages_per_huge_page); 2088 extern void copy_user_huge_page(struct page *dst, struct page *src, 2089 unsigned long addr, struct vm_area_struct *vma, 2090 unsigned int pages_per_huge_page); 2091 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */ 2092 2093 #ifdef CONFIG_DEBUG_PAGEALLOC 2094 extern unsigned int _debug_guardpage_minorder; 2095 2096 static inline unsigned int debug_guardpage_minorder(void) 2097 { 2098 return _debug_guardpage_minorder; 2099 } 2100 2101 static inline bool page_is_guard(struct page *page) 2102 { 2103 return test_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags); 2104 } 2105 #else 2106 static inline unsigned int debug_guardpage_minorder(void) { return 0; } 2107 static inline bool page_is_guard(struct page *page) { return false; } 2108 #endif /* CONFIG_DEBUG_PAGEALLOC */ 2109 2110 #if MAX_NUMNODES > 1 2111 void __init setup_nr_node_ids(void); 2112 #else 2113 static inline void setup_nr_node_ids(void) {} 2114 #endif 2115 2116 #endif /* __KERNEL__ */ 2117 #endif /* _LINUX_MM_H */ 2118