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