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 #include <linux/resource.h> 22 #include <linux/page_ext.h> 23 24 struct mempolicy; 25 struct anon_vma; 26 struct anon_vma_chain; 27 struct file_ra_state; 28 struct user_struct; 29 struct writeback_control; 30 31 #ifndef CONFIG_NEED_MULTIPLE_NODES /* Don't use mapnrs, do it properly */ 32 extern unsigned long max_mapnr; 33 34 static inline void set_max_mapnr(unsigned long limit) 35 { 36 max_mapnr = limit; 37 } 38 #else 39 static inline void set_max_mapnr(unsigned long limit) { } 40 #endif 41 42 extern unsigned long totalram_pages; 43 extern void * high_memory; 44 extern int page_cluster; 45 46 #ifdef CONFIG_SYSCTL 47 extern int sysctl_legacy_va_layout; 48 #else 49 #define sysctl_legacy_va_layout 0 50 #endif 51 52 #include <asm/page.h> 53 #include <asm/pgtable.h> 54 #include <asm/processor.h> 55 56 #ifndef __pa_symbol 57 #define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0)) 58 #endif 59 60 /* 61 * To prevent common memory management code establishing 62 * a zero page mapping on a read fault. 63 * This macro should be defined within <asm/pgtable.h>. 64 * s390 does this to prevent multiplexing of hardware bits 65 * related to the physical page in case of virtualization. 66 */ 67 #ifndef mm_forbids_zeropage 68 #define mm_forbids_zeropage(X) (0) 69 #endif 70 71 extern unsigned long sysctl_user_reserve_kbytes; 72 extern unsigned long sysctl_admin_reserve_kbytes; 73 74 extern int sysctl_overcommit_memory; 75 extern int sysctl_overcommit_ratio; 76 extern unsigned long sysctl_overcommit_kbytes; 77 78 extern int overcommit_ratio_handler(struct ctl_table *, int, void __user *, 79 size_t *, loff_t *); 80 extern int overcommit_kbytes_handler(struct ctl_table *, int, void __user *, 81 size_t *, loff_t *); 82 83 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n)) 84 85 /* to align the pointer to the (next) page boundary */ 86 #define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE) 87 88 /* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */ 89 #define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)addr, PAGE_SIZE) 90 91 /* 92 * Linux kernel virtual memory manager primitives. 93 * The idea being to have a "virtual" mm in the same way 94 * we have a virtual fs - giving a cleaner interface to the 95 * mm details, and allowing different kinds of memory mappings 96 * (from shared memory to executable loading to arbitrary 97 * mmap() functions). 98 */ 99 100 extern struct kmem_cache *vm_area_cachep; 101 102 #ifndef CONFIG_MMU 103 extern struct rb_root nommu_region_tree; 104 extern struct rw_semaphore nommu_region_sem; 105 106 extern unsigned int kobjsize(const void *objp); 107 #endif 108 109 /* 110 * vm_flags in vm_area_struct, see mm_types.h. 111 */ 112 #define VM_NONE 0x00000000 113 114 #define VM_READ 0x00000001 /* currently active flags */ 115 #define VM_WRITE 0x00000002 116 #define VM_EXEC 0x00000004 117 #define VM_SHARED 0x00000008 118 119 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */ 120 #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */ 121 #define VM_MAYWRITE 0x00000020 122 #define VM_MAYEXEC 0x00000040 123 #define VM_MAYSHARE 0x00000080 124 125 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */ 126 #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */ 127 #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */ 128 129 #define VM_LOCKED 0x00002000 130 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */ 131 132 /* Used by sys_madvise() */ 133 #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ 134 #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */ 135 136 #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ 137 #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ 138 #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ 139 #define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */ 140 #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ 141 #define VM_ARCH_1 0x01000000 /* Architecture-specific flag */ 142 #define VM_ARCH_2 0x02000000 143 #define VM_DONTDUMP 0x04000000 /* Do not include in the core dump */ 144 145 #ifdef CONFIG_MEM_SOFT_DIRTY 146 # define VM_SOFTDIRTY 0x08000000 /* Not soft dirty clean area */ 147 #else 148 # define VM_SOFTDIRTY 0 149 #endif 150 151 #define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */ 152 #define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */ 153 #define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */ 154 #define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */ 155 156 #if defined(CONFIG_X86) 157 # define VM_PAT VM_ARCH_1 /* PAT reserves whole VMA at once (x86) */ 158 #elif defined(CONFIG_PPC) 159 # define VM_SAO VM_ARCH_1 /* Strong Access Ordering (powerpc) */ 160 #elif defined(CONFIG_PARISC) 161 # define VM_GROWSUP VM_ARCH_1 162 #elif defined(CONFIG_METAG) 163 # define VM_GROWSUP VM_ARCH_1 164 #elif defined(CONFIG_IA64) 165 # define VM_GROWSUP VM_ARCH_1 166 #elif !defined(CONFIG_MMU) 167 # define VM_MAPPED_COPY VM_ARCH_1 /* T if mapped copy of data (nommu mmap) */ 168 #endif 169 170 #if defined(CONFIG_X86) 171 /* MPX specific bounds table or bounds directory */ 172 # define VM_MPX VM_ARCH_2 173 #endif 174 175 #ifndef VM_GROWSUP 176 # define VM_GROWSUP VM_NONE 177 #endif 178 179 /* Bits set in the VMA until the stack is in its final location */ 180 #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ) 181 182 #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */ 183 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS 184 #endif 185 186 #ifdef CONFIG_STACK_GROWSUP 187 #define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 188 #else 189 #define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 190 #endif 191 192 /* 193 * Special vmas that are non-mergable, non-mlock()able. 194 * Note: mm/huge_memory.c VM_NO_THP depends on this definition. 195 */ 196 #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP) 197 198 /* This mask defines which mm->def_flags a process can inherit its parent */ 199 #define VM_INIT_DEF_MASK VM_NOHUGEPAGE 200 201 /* 202 * mapping from the currently active vm_flags protection bits (the 203 * low four bits) to a page protection mask.. 204 */ 205 extern pgprot_t protection_map[16]; 206 207 #define FAULT_FLAG_WRITE 0x01 /* Fault was a write access */ 208 #define FAULT_FLAG_MKWRITE 0x02 /* Fault was mkwrite of existing pte */ 209 #define FAULT_FLAG_ALLOW_RETRY 0x04 /* Retry fault if blocking */ 210 #define FAULT_FLAG_RETRY_NOWAIT 0x08 /* Don't drop mmap_sem and wait when retrying */ 211 #define FAULT_FLAG_KILLABLE 0x10 /* The fault task is in SIGKILL killable region */ 212 #define FAULT_FLAG_TRIED 0x20 /* Second try */ 213 #define FAULT_FLAG_USER 0x40 /* The fault originated in userspace */ 214 215 /* 216 * vm_fault is filled by the the pagefault handler and passed to the vma's 217 * ->fault function. The vma's ->fault is responsible for returning a bitmask 218 * of VM_FAULT_xxx flags that give details about how the fault was handled. 219 * 220 * pgoff should be used in favour of virtual_address, if possible. 221 */ 222 struct vm_fault { 223 unsigned int flags; /* FAULT_FLAG_xxx flags */ 224 pgoff_t pgoff; /* Logical page offset based on vma */ 225 void __user *virtual_address; /* Faulting virtual address */ 226 227 struct page *cow_page; /* Handler may choose to COW */ 228 struct page *page; /* ->fault handlers should return a 229 * page here, unless VM_FAULT_NOPAGE 230 * is set (which is also implied by 231 * VM_FAULT_ERROR). 232 */ 233 /* for ->map_pages() only */ 234 pgoff_t max_pgoff; /* map pages for offset from pgoff till 235 * max_pgoff inclusive */ 236 pte_t *pte; /* pte entry associated with ->pgoff */ 237 }; 238 239 /* 240 * These are the virtual MM functions - opening of an area, closing and 241 * unmapping it (needed to keep files on disk up-to-date etc), pointer 242 * to the functions called when a no-page or a wp-page exception occurs. 243 */ 244 struct vm_operations_struct { 245 void (*open)(struct vm_area_struct * area); 246 void (*close)(struct vm_area_struct * area); 247 int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf); 248 void (*map_pages)(struct vm_area_struct *vma, struct vm_fault *vmf); 249 250 /* notification that a previously read-only page is about to become 251 * writable, if an error is returned it will cause a SIGBUS */ 252 int (*page_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf); 253 254 /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */ 255 int (*pfn_mkwrite)(struct vm_area_struct *vma, struct vm_fault *vmf); 256 257 /* called by access_process_vm when get_user_pages() fails, typically 258 * for use by special VMAs that can switch between memory and hardware 259 */ 260 int (*access)(struct vm_area_struct *vma, unsigned long addr, 261 void *buf, int len, int write); 262 263 /* Called by the /proc/PID/maps code to ask the vma whether it 264 * has a special name. Returning non-NULL will also cause this 265 * vma to be dumped unconditionally. */ 266 const char *(*name)(struct vm_area_struct *vma); 267 268 #ifdef CONFIG_NUMA 269 /* 270 * set_policy() op must add a reference to any non-NULL @new mempolicy 271 * to hold the policy upon return. Caller should pass NULL @new to 272 * remove a policy and fall back to surrounding context--i.e. do not 273 * install a MPOL_DEFAULT policy, nor the task or system default 274 * mempolicy. 275 */ 276 int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); 277 278 /* 279 * get_policy() op must add reference [mpol_get()] to any policy at 280 * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure 281 * in mm/mempolicy.c will do this automatically. 282 * get_policy() must NOT add a ref if the policy at (vma,addr) is not 283 * marked as MPOL_SHARED. vma policies are protected by the mmap_sem. 284 * If no [shared/vma] mempolicy exists at the addr, get_policy() op 285 * must return NULL--i.e., do not "fallback" to task or system default 286 * policy. 287 */ 288 struct mempolicy *(*get_policy)(struct vm_area_struct *vma, 289 unsigned long addr); 290 #endif 291 /* 292 * Called by vm_normal_page() for special PTEs to find the 293 * page for @addr. This is useful if the default behavior 294 * (using pte_page()) would not find the correct page. 295 */ 296 struct page *(*find_special_page)(struct vm_area_struct *vma, 297 unsigned long addr); 298 }; 299 300 struct mmu_gather; 301 struct inode; 302 303 #define page_private(page) ((page)->private) 304 #define set_page_private(page, v) ((page)->private = (v)) 305 306 /* It's valid only if the page is free path or free_list */ 307 static inline void set_freepage_migratetype(struct page *page, int migratetype) 308 { 309 page->index = migratetype; 310 } 311 312 /* It's valid only if the page is free path or free_list */ 313 static inline int get_freepage_migratetype(struct page *page) 314 { 315 return page->index; 316 } 317 318 /* 319 * FIXME: take this include out, include page-flags.h in 320 * files which need it (119 of them) 321 */ 322 #include <linux/page-flags.h> 323 #include <linux/huge_mm.h> 324 325 /* 326 * Methods to modify the page usage count. 327 * 328 * What counts for a page usage: 329 * - cache mapping (page->mapping) 330 * - private data (page->private) 331 * - page mapped in a task's page tables, each mapping 332 * is counted separately 333 * 334 * Also, many kernel routines increase the page count before a critical 335 * routine so they can be sure the page doesn't go away from under them. 336 */ 337 338 /* 339 * Drop a ref, return true if the refcount fell to zero (the page has no users) 340 */ 341 static inline int put_page_testzero(struct page *page) 342 { 343 VM_BUG_ON_PAGE(atomic_read(&page->_count) == 0, page); 344 return atomic_dec_and_test(&page->_count); 345 } 346 347 /* 348 * Try to grab a ref unless the page has a refcount of zero, return false if 349 * that is the case. 350 * This can be called when MMU is off so it must not access 351 * any of the virtual mappings. 352 */ 353 static inline int get_page_unless_zero(struct page *page) 354 { 355 return atomic_inc_not_zero(&page->_count); 356 } 357 358 /* 359 * Try to drop a ref unless the page has a refcount of one, return false if 360 * that is the case. 361 * This is to make sure that the refcount won't become zero after this drop. 362 * This can be called when MMU is off so it must not access 363 * any of the virtual mappings. 364 */ 365 static inline int put_page_unless_one(struct page *page) 366 { 367 return atomic_add_unless(&page->_count, -1, 1); 368 } 369 370 extern int page_is_ram(unsigned long pfn); 371 extern int region_is_ram(resource_size_t phys_addr, unsigned long size); 372 373 /* Support for virtually mapped pages */ 374 struct page *vmalloc_to_page(const void *addr); 375 unsigned long vmalloc_to_pfn(const void *addr); 376 377 /* 378 * Determine if an address is within the vmalloc range 379 * 380 * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there 381 * is no special casing required. 382 */ 383 static inline int is_vmalloc_addr(const void *x) 384 { 385 #ifdef CONFIG_MMU 386 unsigned long addr = (unsigned long)x; 387 388 return addr >= VMALLOC_START && addr < VMALLOC_END; 389 #else 390 return 0; 391 #endif 392 } 393 #ifdef CONFIG_MMU 394 extern int is_vmalloc_or_module_addr(const void *x); 395 #else 396 static inline int is_vmalloc_or_module_addr(const void *x) 397 { 398 return 0; 399 } 400 #endif 401 402 extern void kvfree(const void *addr); 403 404 static inline void compound_lock(struct page *page) 405 { 406 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 407 VM_BUG_ON_PAGE(PageSlab(page), page); 408 bit_spin_lock(PG_compound_lock, &page->flags); 409 #endif 410 } 411 412 static inline void compound_unlock(struct page *page) 413 { 414 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 415 VM_BUG_ON_PAGE(PageSlab(page), page); 416 bit_spin_unlock(PG_compound_lock, &page->flags); 417 #endif 418 } 419 420 static inline unsigned long compound_lock_irqsave(struct page *page) 421 { 422 unsigned long uninitialized_var(flags); 423 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 424 local_irq_save(flags); 425 compound_lock(page); 426 #endif 427 return flags; 428 } 429 430 static inline void compound_unlock_irqrestore(struct page *page, 431 unsigned long flags) 432 { 433 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 434 compound_unlock(page); 435 local_irq_restore(flags); 436 #endif 437 } 438 439 static inline struct page *compound_head_by_tail(struct page *tail) 440 { 441 struct page *head = tail->first_page; 442 443 /* 444 * page->first_page may be a dangling pointer to an old 445 * compound page, so recheck that it is still a tail 446 * page before returning. 447 */ 448 smp_rmb(); 449 if (likely(PageTail(tail))) 450 return head; 451 return tail; 452 } 453 454 /* 455 * Since either compound page could be dismantled asynchronously in THP 456 * or we access asynchronously arbitrary positioned struct page, there 457 * would be tail flag race. To handle this race, we should call 458 * smp_rmb() before checking tail flag. compound_head_by_tail() did it. 459 */ 460 static inline struct page *compound_head(struct page *page) 461 { 462 if (unlikely(PageTail(page))) 463 return compound_head_by_tail(page); 464 return page; 465 } 466 467 /* 468 * If we access compound page synchronously such as access to 469 * allocated page, there is no need to handle tail flag race, so we can 470 * check tail flag directly without any synchronization primitive. 471 */ 472 static inline struct page *compound_head_fast(struct page *page) 473 { 474 if (unlikely(PageTail(page))) 475 return page->first_page; 476 return page; 477 } 478 479 /* 480 * The atomic page->_mapcount, starts from -1: so that transitions 481 * both from it and to it can be tracked, using atomic_inc_and_test 482 * and atomic_add_negative(-1). 483 */ 484 static inline void page_mapcount_reset(struct page *page) 485 { 486 atomic_set(&(page)->_mapcount, -1); 487 } 488 489 static inline int page_mapcount(struct page *page) 490 { 491 VM_BUG_ON_PAGE(PageSlab(page), page); 492 return atomic_read(&page->_mapcount) + 1; 493 } 494 495 static inline int page_count(struct page *page) 496 { 497 return atomic_read(&compound_head(page)->_count); 498 } 499 500 static inline bool __compound_tail_refcounted(struct page *page) 501 { 502 return PageAnon(page) && !PageSlab(page) && !PageHeadHuge(page); 503 } 504 505 /* 506 * This takes a head page as parameter and tells if the 507 * tail page reference counting can be skipped. 508 * 509 * For this to be safe, PageSlab and PageHeadHuge must remain true on 510 * any given page where they return true here, until all tail pins 511 * have been released. 512 */ 513 static inline bool compound_tail_refcounted(struct page *page) 514 { 515 VM_BUG_ON_PAGE(!PageHead(page), page); 516 return __compound_tail_refcounted(page); 517 } 518 519 static inline void get_huge_page_tail(struct page *page) 520 { 521 /* 522 * __split_huge_page_refcount() cannot run from under us. 523 */ 524 VM_BUG_ON_PAGE(!PageTail(page), page); 525 VM_BUG_ON_PAGE(page_mapcount(page) < 0, page); 526 VM_BUG_ON_PAGE(atomic_read(&page->_count) != 0, page); 527 if (compound_tail_refcounted(page->first_page)) 528 atomic_inc(&page->_mapcount); 529 } 530 531 extern bool __get_page_tail(struct page *page); 532 533 static inline void get_page(struct page *page) 534 { 535 if (unlikely(PageTail(page))) 536 if (likely(__get_page_tail(page))) 537 return; 538 /* 539 * Getting a normal page or the head of a compound page 540 * requires to already have an elevated page->_count. 541 */ 542 VM_BUG_ON_PAGE(atomic_read(&page->_count) <= 0, page); 543 atomic_inc(&page->_count); 544 } 545 546 static inline struct page *virt_to_head_page(const void *x) 547 { 548 struct page *page = virt_to_page(x); 549 550 /* 551 * We don't need to worry about synchronization of tail flag 552 * when we call virt_to_head_page() since it is only called for 553 * already allocated page and this page won't be freed until 554 * this virt_to_head_page() is finished. So use _fast variant. 555 */ 556 return compound_head_fast(page); 557 } 558 559 /* 560 * Setup the page count before being freed into the page allocator for 561 * the first time (boot or memory hotplug) 562 */ 563 static inline void init_page_count(struct page *page) 564 { 565 atomic_set(&page->_count, 1); 566 } 567 568 void put_page(struct page *page); 569 void put_pages_list(struct list_head *pages); 570 571 void split_page(struct page *page, unsigned int order); 572 int split_free_page(struct page *page); 573 574 /* 575 * Compound pages have a destructor function. Provide a 576 * prototype for that function and accessor functions. 577 * These are _only_ valid on the head of a PG_compound page. 578 */ 579 580 static inline void set_compound_page_dtor(struct page *page, 581 compound_page_dtor *dtor) 582 { 583 page[1].compound_dtor = dtor; 584 } 585 586 static inline compound_page_dtor *get_compound_page_dtor(struct page *page) 587 { 588 return page[1].compound_dtor; 589 } 590 591 static inline int compound_order(struct page *page) 592 { 593 if (!PageHead(page)) 594 return 0; 595 return page[1].compound_order; 596 } 597 598 static inline void set_compound_order(struct page *page, unsigned long order) 599 { 600 page[1].compound_order = order; 601 } 602 603 #ifdef CONFIG_MMU 604 /* 605 * Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when 606 * servicing faults for write access. In the normal case, do always want 607 * pte_mkwrite. But get_user_pages can cause write faults for mappings 608 * that do not have writing enabled, when used by access_process_vm. 609 */ 610 static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma) 611 { 612 if (likely(vma->vm_flags & VM_WRITE)) 613 pte = pte_mkwrite(pte); 614 return pte; 615 } 616 617 void do_set_pte(struct vm_area_struct *vma, unsigned long address, 618 struct page *page, pte_t *pte, bool write, bool anon); 619 #endif 620 621 /* 622 * Multiple processes may "see" the same page. E.g. for untouched 623 * mappings of /dev/null, all processes see the same page full of 624 * zeroes, and text pages of executables and shared libraries have 625 * only one copy in memory, at most, normally. 626 * 627 * For the non-reserved pages, page_count(page) denotes a reference count. 628 * page_count() == 0 means the page is free. page->lru is then used for 629 * freelist management in the buddy allocator. 630 * page_count() > 0 means the page has been allocated. 631 * 632 * Pages are allocated by the slab allocator in order to provide memory 633 * to kmalloc and kmem_cache_alloc. In this case, the management of the 634 * page, and the fields in 'struct page' are the responsibility of mm/slab.c 635 * unless a particular usage is carefully commented. (the responsibility of 636 * freeing the kmalloc memory is the caller's, of course). 637 * 638 * A page may be used by anyone else who does a __get_free_page(). 639 * In this case, page_count still tracks the references, and should only 640 * be used through the normal accessor functions. The top bits of page->flags 641 * and page->virtual store page management information, but all other fields 642 * are unused and could be used privately, carefully. The management of this 643 * page is the responsibility of the one who allocated it, and those who have 644 * subsequently been given references to it. 645 * 646 * The other pages (we may call them "pagecache pages") are completely 647 * managed by the Linux memory manager: I/O, buffers, swapping etc. 648 * The following discussion applies only to them. 649 * 650 * A pagecache page contains an opaque `private' member, which belongs to the 651 * page's address_space. Usually, this is the address of a circular list of 652 * the page's disk buffers. PG_private must be set to tell the VM to call 653 * into the filesystem to release these pages. 654 * 655 * A page may belong to an inode's memory mapping. In this case, page->mapping 656 * is the pointer to the inode, and page->index is the file offset of the page, 657 * in units of PAGE_CACHE_SIZE. 658 * 659 * If pagecache pages are not associated with an inode, they are said to be 660 * anonymous pages. These may become associated with the swapcache, and in that 661 * case PG_swapcache is set, and page->private is an offset into the swapcache. 662 * 663 * In either case (swapcache or inode backed), the pagecache itself holds one 664 * reference to the page. Setting PG_private should also increment the 665 * refcount. The each user mapping also has a reference to the page. 666 * 667 * The pagecache pages are stored in a per-mapping radix tree, which is 668 * rooted at mapping->page_tree, and indexed by offset. 669 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space 670 * lists, we instead now tag pages as dirty/writeback in the radix tree. 671 * 672 * All pagecache pages may be subject to I/O: 673 * - inode pages may need to be read from disk, 674 * - inode pages which have been modified and are MAP_SHARED may need 675 * to be written back to the inode on disk, 676 * - anonymous pages (including MAP_PRIVATE file mappings) which have been 677 * modified may need to be swapped out to swap space and (later) to be read 678 * back into memory. 679 */ 680 681 /* 682 * The zone field is never updated after free_area_init_core() 683 * sets it, so none of the operations on it need to be atomic. 684 */ 685 686 /* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_CPUPID] | ... | FLAGS | */ 687 #define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH) 688 #define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH) 689 #define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH) 690 #define LAST_CPUPID_PGOFF (ZONES_PGOFF - LAST_CPUPID_WIDTH) 691 692 /* 693 * Define the bit shifts to access each section. For non-existent 694 * sections we define the shift as 0; that plus a 0 mask ensures 695 * the compiler will optimise away reference to them. 696 */ 697 #define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0)) 698 #define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0)) 699 #define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0)) 700 #define LAST_CPUPID_PGSHIFT (LAST_CPUPID_PGOFF * (LAST_CPUPID_WIDTH != 0)) 701 702 /* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */ 703 #ifdef NODE_NOT_IN_PAGE_FLAGS 704 #define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT) 705 #define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \ 706 SECTIONS_PGOFF : ZONES_PGOFF) 707 #else 708 #define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT) 709 #define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \ 710 NODES_PGOFF : ZONES_PGOFF) 711 #endif 712 713 #define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0)) 714 715 #if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS 716 #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS 717 #endif 718 719 #define ZONES_MASK ((1UL << ZONES_WIDTH) - 1) 720 #define NODES_MASK ((1UL << NODES_WIDTH) - 1) 721 #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1) 722 #define LAST_CPUPID_MASK ((1UL << LAST_CPUPID_SHIFT) - 1) 723 #define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1) 724 725 static inline enum zone_type page_zonenum(const struct page *page) 726 { 727 return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; 728 } 729 730 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) 731 #define SECTION_IN_PAGE_FLAGS 732 #endif 733 734 /* 735 * The identification function is mainly used by the buddy allocator for 736 * determining if two pages could be buddies. We are not really identifying 737 * the zone since we could be using the section number id if we do not have 738 * node id available in page flags. 739 * We only guarantee that it will return the same value for two combinable 740 * pages in a zone. 741 */ 742 static inline int page_zone_id(struct page *page) 743 { 744 return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK; 745 } 746 747 static inline int zone_to_nid(struct zone *zone) 748 { 749 #ifdef CONFIG_NUMA 750 return zone->node; 751 #else 752 return 0; 753 #endif 754 } 755 756 #ifdef NODE_NOT_IN_PAGE_FLAGS 757 extern int page_to_nid(const struct page *page); 758 #else 759 static inline int page_to_nid(const struct page *page) 760 { 761 return (page->flags >> NODES_PGSHIFT) & NODES_MASK; 762 } 763 #endif 764 765 #ifdef CONFIG_NUMA_BALANCING 766 static inline int cpu_pid_to_cpupid(int cpu, int pid) 767 { 768 return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK); 769 } 770 771 static inline int cpupid_to_pid(int cpupid) 772 { 773 return cpupid & LAST__PID_MASK; 774 } 775 776 static inline int cpupid_to_cpu(int cpupid) 777 { 778 return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK; 779 } 780 781 static inline int cpupid_to_nid(int cpupid) 782 { 783 return cpu_to_node(cpupid_to_cpu(cpupid)); 784 } 785 786 static inline bool cpupid_pid_unset(int cpupid) 787 { 788 return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK); 789 } 790 791 static inline bool cpupid_cpu_unset(int cpupid) 792 { 793 return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK); 794 } 795 796 static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid) 797 { 798 return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid); 799 } 800 801 #define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid) 802 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS 803 static inline int page_cpupid_xchg_last(struct page *page, int cpupid) 804 { 805 return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK); 806 } 807 808 static inline int page_cpupid_last(struct page *page) 809 { 810 return page->_last_cpupid; 811 } 812 static inline void page_cpupid_reset_last(struct page *page) 813 { 814 page->_last_cpupid = -1 & LAST_CPUPID_MASK; 815 } 816 #else 817 static inline int page_cpupid_last(struct page *page) 818 { 819 return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK; 820 } 821 822 extern int page_cpupid_xchg_last(struct page *page, int cpupid); 823 824 static inline void page_cpupid_reset_last(struct page *page) 825 { 826 int cpupid = (1 << LAST_CPUPID_SHIFT) - 1; 827 828 page->flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT); 829 page->flags |= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT; 830 } 831 #endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */ 832 #else /* !CONFIG_NUMA_BALANCING */ 833 static inline int page_cpupid_xchg_last(struct page *page, int cpupid) 834 { 835 return page_to_nid(page); /* XXX */ 836 } 837 838 static inline int page_cpupid_last(struct page *page) 839 { 840 return page_to_nid(page); /* XXX */ 841 } 842 843 static inline int cpupid_to_nid(int cpupid) 844 { 845 return -1; 846 } 847 848 static inline int cpupid_to_pid(int cpupid) 849 { 850 return -1; 851 } 852 853 static inline int cpupid_to_cpu(int cpupid) 854 { 855 return -1; 856 } 857 858 static inline int cpu_pid_to_cpupid(int nid, int pid) 859 { 860 return -1; 861 } 862 863 static inline bool cpupid_pid_unset(int cpupid) 864 { 865 return 1; 866 } 867 868 static inline void page_cpupid_reset_last(struct page *page) 869 { 870 } 871 872 static inline bool cpupid_match_pid(struct task_struct *task, int cpupid) 873 { 874 return false; 875 } 876 #endif /* CONFIG_NUMA_BALANCING */ 877 878 static inline struct zone *page_zone(const struct page *page) 879 { 880 return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)]; 881 } 882 883 #ifdef SECTION_IN_PAGE_FLAGS 884 static inline void set_page_section(struct page *page, unsigned long section) 885 { 886 page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT); 887 page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT; 888 } 889 890 static inline unsigned long page_to_section(const struct page *page) 891 { 892 return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; 893 } 894 #endif 895 896 static inline void set_page_zone(struct page *page, enum zone_type zone) 897 { 898 page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); 899 page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; 900 } 901 902 static inline void set_page_node(struct page *page, unsigned long node) 903 { 904 page->flags &= ~(NODES_MASK << NODES_PGSHIFT); 905 page->flags |= (node & NODES_MASK) << NODES_PGSHIFT; 906 } 907 908 static inline void set_page_links(struct page *page, enum zone_type zone, 909 unsigned long node, unsigned long pfn) 910 { 911 set_page_zone(page, zone); 912 set_page_node(page, node); 913 #ifdef SECTION_IN_PAGE_FLAGS 914 set_page_section(page, pfn_to_section_nr(pfn)); 915 #endif 916 } 917 918 /* 919 * Some inline functions in vmstat.h depend on page_zone() 920 */ 921 #include <linux/vmstat.h> 922 923 static __always_inline void *lowmem_page_address(const struct page *page) 924 { 925 return __va(PFN_PHYS(page_to_pfn(page))); 926 } 927 928 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) 929 #define HASHED_PAGE_VIRTUAL 930 #endif 931 932 #if defined(WANT_PAGE_VIRTUAL) 933 static inline void *page_address(const struct page *page) 934 { 935 return page->virtual; 936 } 937 static inline void set_page_address(struct page *page, void *address) 938 { 939 page->virtual = address; 940 } 941 #define page_address_init() do { } while(0) 942 #endif 943 944 #if defined(HASHED_PAGE_VIRTUAL) 945 void *page_address(const struct page *page); 946 void set_page_address(struct page *page, void *virtual); 947 void page_address_init(void); 948 #endif 949 950 #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL) 951 #define page_address(page) lowmem_page_address(page) 952 #define set_page_address(page, address) do { } while(0) 953 #define page_address_init() do { } while(0) 954 #endif 955 956 extern void *page_rmapping(struct page *page); 957 extern struct anon_vma *page_anon_vma(struct page *page); 958 extern struct address_space *page_mapping(struct page *page); 959 960 extern struct address_space *__page_file_mapping(struct page *); 961 962 static inline 963 struct address_space *page_file_mapping(struct page *page) 964 { 965 if (unlikely(PageSwapCache(page))) 966 return __page_file_mapping(page); 967 968 return page->mapping; 969 } 970 971 /* 972 * Return the pagecache index of the passed page. Regular pagecache pages 973 * use ->index whereas swapcache pages use ->private 974 */ 975 static inline pgoff_t page_index(struct page *page) 976 { 977 if (unlikely(PageSwapCache(page))) 978 return page_private(page); 979 return page->index; 980 } 981 982 extern pgoff_t __page_file_index(struct page *page); 983 984 /* 985 * Return the file index of the page. Regular pagecache pages use ->index 986 * whereas swapcache pages use swp_offset(->private) 987 */ 988 static inline pgoff_t page_file_index(struct page *page) 989 { 990 if (unlikely(PageSwapCache(page))) 991 return __page_file_index(page); 992 993 return page->index; 994 } 995 996 /* 997 * Return true if this page is mapped into pagetables. 998 */ 999 static inline int page_mapped(struct page *page) 1000 { 1001 return atomic_read(&(page)->_mapcount) >= 0; 1002 } 1003 1004 /* 1005 * Different kinds of faults, as returned by handle_mm_fault(). 1006 * Used to decide whether a process gets delivered SIGBUS or 1007 * just gets major/minor fault counters bumped up. 1008 */ 1009 1010 #define VM_FAULT_MINOR 0 /* For backwards compat. Remove me quickly. */ 1011 1012 #define VM_FAULT_OOM 0x0001 1013 #define VM_FAULT_SIGBUS 0x0002 1014 #define VM_FAULT_MAJOR 0x0004 1015 #define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */ 1016 #define VM_FAULT_HWPOISON 0x0010 /* Hit poisoned small page */ 1017 #define VM_FAULT_HWPOISON_LARGE 0x0020 /* Hit poisoned large page. Index encoded in upper bits */ 1018 #define VM_FAULT_SIGSEGV 0x0040 1019 1020 #define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */ 1021 #define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */ 1022 #define VM_FAULT_RETRY 0x0400 /* ->fault blocked, must retry */ 1023 #define VM_FAULT_FALLBACK 0x0800 /* huge page fault failed, fall back to small */ 1024 1025 #define VM_FAULT_HWPOISON_LARGE_MASK 0xf000 /* encodes hpage index for large hwpoison */ 1026 1027 #define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | VM_FAULT_SIGSEGV | \ 1028 VM_FAULT_HWPOISON | VM_FAULT_HWPOISON_LARGE | \ 1029 VM_FAULT_FALLBACK) 1030 1031 /* Encode hstate index for a hwpoisoned large page */ 1032 #define VM_FAULT_SET_HINDEX(x) ((x) << 12) 1033 #define VM_FAULT_GET_HINDEX(x) (((x) >> 12) & 0xf) 1034 1035 /* 1036 * Can be called by the pagefault handler when it gets a VM_FAULT_OOM. 1037 */ 1038 extern void pagefault_out_of_memory(void); 1039 1040 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) 1041 1042 /* 1043 * Flags passed to show_mem() and show_free_areas() to suppress output in 1044 * various contexts. 1045 */ 1046 #define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */ 1047 1048 extern void show_free_areas(unsigned int flags); 1049 extern bool skip_free_areas_node(unsigned int flags, int nid); 1050 1051 int shmem_zero_setup(struct vm_area_struct *); 1052 #ifdef CONFIG_SHMEM 1053 bool shmem_mapping(struct address_space *mapping); 1054 #else 1055 static inline bool shmem_mapping(struct address_space *mapping) 1056 { 1057 return false; 1058 } 1059 #endif 1060 1061 extern int can_do_mlock(void); 1062 extern int user_shm_lock(size_t, struct user_struct *); 1063 extern void user_shm_unlock(size_t, struct user_struct *); 1064 1065 /* 1066 * Parameter block passed down to zap_pte_range in exceptional cases. 1067 */ 1068 struct zap_details { 1069 struct address_space *check_mapping; /* Check page->mapping if set */ 1070 pgoff_t first_index; /* Lowest page->index to unmap */ 1071 pgoff_t last_index; /* Highest page->index to unmap */ 1072 }; 1073 1074 struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, 1075 pte_t pte); 1076 1077 int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address, 1078 unsigned long size); 1079 void zap_page_range(struct vm_area_struct *vma, unsigned long address, 1080 unsigned long size, struct zap_details *); 1081 void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma, 1082 unsigned long start, unsigned long end); 1083 1084 /** 1085 * mm_walk - callbacks for walk_page_range 1086 * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry 1087 * this handler is required to be able to handle 1088 * pmd_trans_huge() pmds. They may simply choose to 1089 * split_huge_page() instead of handling it explicitly. 1090 * @pte_entry: if set, called for each non-empty PTE (4th-level) entry 1091 * @pte_hole: if set, called for each hole at all levels 1092 * @hugetlb_entry: if set, called for each hugetlb entry 1093 * @test_walk: caller specific callback function to determine whether 1094 * we walk over the current vma or not. A positive returned 1095 * value means "do page table walk over the current vma," 1096 * and a negative one means "abort current page table walk 1097 * right now." 0 means "skip the current vma." 1098 * @mm: mm_struct representing the target process of page table walk 1099 * @vma: vma currently walked (NULL if walking outside vmas) 1100 * @private: private data for callbacks' usage 1101 * 1102 * (see the comment on walk_page_range() for more details) 1103 */ 1104 struct mm_walk { 1105 int (*pmd_entry)(pmd_t *pmd, unsigned long addr, 1106 unsigned long next, struct mm_walk *walk); 1107 int (*pte_entry)(pte_t *pte, unsigned long addr, 1108 unsigned long next, struct mm_walk *walk); 1109 int (*pte_hole)(unsigned long addr, unsigned long next, 1110 struct mm_walk *walk); 1111 int (*hugetlb_entry)(pte_t *pte, unsigned long hmask, 1112 unsigned long addr, unsigned long next, 1113 struct mm_walk *walk); 1114 int (*test_walk)(unsigned long addr, unsigned long next, 1115 struct mm_walk *walk); 1116 struct mm_struct *mm; 1117 struct vm_area_struct *vma; 1118 void *private; 1119 }; 1120 1121 int walk_page_range(unsigned long addr, unsigned long end, 1122 struct mm_walk *walk); 1123 int walk_page_vma(struct vm_area_struct *vma, struct mm_walk *walk); 1124 void free_pgd_range(struct mmu_gather *tlb, unsigned long addr, 1125 unsigned long end, unsigned long floor, unsigned long ceiling); 1126 int copy_page_range(struct mm_struct *dst, struct mm_struct *src, 1127 struct vm_area_struct *vma); 1128 void unmap_mapping_range(struct address_space *mapping, 1129 loff_t const holebegin, loff_t const holelen, int even_cows); 1130 int follow_pfn(struct vm_area_struct *vma, unsigned long address, 1131 unsigned long *pfn); 1132 int follow_phys(struct vm_area_struct *vma, unsigned long address, 1133 unsigned int flags, unsigned long *prot, resource_size_t *phys); 1134 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr, 1135 void *buf, int len, int write); 1136 1137 static inline void unmap_shared_mapping_range(struct address_space *mapping, 1138 loff_t const holebegin, loff_t const holelen) 1139 { 1140 unmap_mapping_range(mapping, holebegin, holelen, 0); 1141 } 1142 1143 extern void truncate_pagecache(struct inode *inode, loff_t new); 1144 extern void truncate_setsize(struct inode *inode, loff_t newsize); 1145 void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to); 1146 void truncate_pagecache_range(struct inode *inode, loff_t offset, loff_t end); 1147 int truncate_inode_page(struct address_space *mapping, struct page *page); 1148 int generic_error_remove_page(struct address_space *mapping, struct page *page); 1149 int invalidate_inode_page(struct page *page); 1150 1151 #ifdef CONFIG_MMU 1152 extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, 1153 unsigned long address, unsigned int flags); 1154 extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm, 1155 unsigned long address, unsigned int fault_flags); 1156 #else 1157 static inline int handle_mm_fault(struct mm_struct *mm, 1158 struct vm_area_struct *vma, unsigned long address, 1159 unsigned int flags) 1160 { 1161 /* should never happen if there's no MMU */ 1162 BUG(); 1163 return VM_FAULT_SIGBUS; 1164 } 1165 static inline int fixup_user_fault(struct task_struct *tsk, 1166 struct mm_struct *mm, unsigned long address, 1167 unsigned int fault_flags) 1168 { 1169 /* should never happen if there's no MMU */ 1170 BUG(); 1171 return -EFAULT; 1172 } 1173 #endif 1174 1175 extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write); 1176 extern int access_remote_vm(struct mm_struct *mm, unsigned long addr, 1177 void *buf, int len, int write); 1178 1179 long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, 1180 unsigned long start, unsigned long nr_pages, 1181 unsigned int foll_flags, struct page **pages, 1182 struct vm_area_struct **vmas, int *nonblocking); 1183 long get_user_pages(struct task_struct *tsk, struct mm_struct *mm, 1184 unsigned long start, unsigned long nr_pages, 1185 int write, int force, struct page **pages, 1186 struct vm_area_struct **vmas); 1187 long get_user_pages_locked(struct task_struct *tsk, struct mm_struct *mm, 1188 unsigned long start, unsigned long nr_pages, 1189 int write, int force, struct page **pages, 1190 int *locked); 1191 long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, 1192 unsigned long start, unsigned long nr_pages, 1193 int write, int force, struct page **pages, 1194 unsigned int gup_flags); 1195 long get_user_pages_unlocked(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 int get_user_pages_fast(unsigned long start, int nr_pages, int write, 1199 struct page **pages); 1200 struct kvec; 1201 int get_kernel_pages(const struct kvec *iov, int nr_pages, int write, 1202 struct page **pages); 1203 int get_kernel_page(unsigned long start, int write, struct page **pages); 1204 struct page *get_dump_page(unsigned long addr); 1205 1206 extern int try_to_release_page(struct page * page, gfp_t gfp_mask); 1207 extern void do_invalidatepage(struct page *page, unsigned int offset, 1208 unsigned int length); 1209 1210 int __set_page_dirty_nobuffers(struct page *page); 1211 int __set_page_dirty_no_writeback(struct page *page); 1212 int redirty_page_for_writepage(struct writeback_control *wbc, 1213 struct page *page); 1214 void account_page_dirtied(struct page *page, struct address_space *mapping); 1215 void account_page_cleaned(struct page *page, struct address_space *mapping); 1216 int set_page_dirty(struct page *page); 1217 int set_page_dirty_lock(struct page *page); 1218 int clear_page_dirty_for_io(struct page *page); 1219 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 struct task_struct *task_of_stack(struct task_struct *task, 1251 struct vm_area_struct *vma, bool 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 reset_mm_hiwater_rss(struct mm_struct *mm) 1333 { 1334 mm->hiwater_rss = get_mm_rss(mm); 1335 } 1336 1337 static inline void setmax_mm_hiwater_rss(unsigned long *maxrss, 1338 struct mm_struct *mm) 1339 { 1340 unsigned long hiwater_rss = get_mm_hiwater_rss(mm); 1341 1342 if (*maxrss < hiwater_rss) 1343 *maxrss = hiwater_rss; 1344 } 1345 1346 #if defined(SPLIT_RSS_COUNTING) 1347 void sync_mm_rss(struct mm_struct *mm); 1348 #else 1349 static inline void sync_mm_rss(struct mm_struct *mm) 1350 { 1351 } 1352 #endif 1353 1354 int vma_wants_writenotify(struct vm_area_struct *vma); 1355 1356 extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr, 1357 spinlock_t **ptl); 1358 static inline pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, 1359 spinlock_t **ptl) 1360 { 1361 pte_t *ptep; 1362 __cond_lock(*ptl, ptep = __get_locked_pte(mm, addr, ptl)); 1363 return ptep; 1364 } 1365 1366 #ifdef __PAGETABLE_PUD_FOLDED 1367 static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, 1368 unsigned long address) 1369 { 1370 return 0; 1371 } 1372 #else 1373 int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); 1374 #endif 1375 1376 #if defined(__PAGETABLE_PMD_FOLDED) || !defined(CONFIG_MMU) 1377 static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud, 1378 unsigned long address) 1379 { 1380 return 0; 1381 } 1382 1383 static inline void mm_nr_pmds_init(struct mm_struct *mm) {} 1384 1385 static inline unsigned long mm_nr_pmds(struct mm_struct *mm) 1386 { 1387 return 0; 1388 } 1389 1390 static inline void mm_inc_nr_pmds(struct mm_struct *mm) {} 1391 static inline void mm_dec_nr_pmds(struct mm_struct *mm) {} 1392 1393 #else 1394 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); 1395 1396 static inline void mm_nr_pmds_init(struct mm_struct *mm) 1397 { 1398 atomic_long_set(&mm->nr_pmds, 0); 1399 } 1400 1401 static inline unsigned long mm_nr_pmds(struct mm_struct *mm) 1402 { 1403 return atomic_long_read(&mm->nr_pmds); 1404 } 1405 1406 static inline void mm_inc_nr_pmds(struct mm_struct *mm) 1407 { 1408 atomic_long_inc(&mm->nr_pmds); 1409 } 1410 1411 static inline void mm_dec_nr_pmds(struct mm_struct *mm) 1412 { 1413 atomic_long_dec(&mm->nr_pmds); 1414 } 1415 #endif 1416 1417 int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, 1418 pmd_t *pmd, unsigned long address); 1419 int __pte_alloc_kernel(pmd_t *pmd, unsigned long address); 1420 1421 /* 1422 * The following ifdef needed to get the 4level-fixup.h header to work. 1423 * Remove it when 4level-fixup.h has been removed. 1424 */ 1425 #if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK) 1426 static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address) 1427 { 1428 return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))? 1429 NULL: pud_offset(pgd, address); 1430 } 1431 1432 static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) 1433 { 1434 return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))? 1435 NULL: pmd_offset(pud, address); 1436 } 1437 #endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */ 1438 1439 #if USE_SPLIT_PTE_PTLOCKS 1440 #if ALLOC_SPLIT_PTLOCKS 1441 void __init ptlock_cache_init(void); 1442 extern bool ptlock_alloc(struct page *page); 1443 extern void ptlock_free(struct page *page); 1444 1445 static inline spinlock_t *ptlock_ptr(struct page *page) 1446 { 1447 return page->ptl; 1448 } 1449 #else /* ALLOC_SPLIT_PTLOCKS */ 1450 static inline void ptlock_cache_init(void) 1451 { 1452 } 1453 1454 static inline bool ptlock_alloc(struct page *page) 1455 { 1456 return true; 1457 } 1458 1459 static inline void ptlock_free(struct page *page) 1460 { 1461 } 1462 1463 static inline spinlock_t *ptlock_ptr(struct page *page) 1464 { 1465 return &page->ptl; 1466 } 1467 #endif /* ALLOC_SPLIT_PTLOCKS */ 1468 1469 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd) 1470 { 1471 return ptlock_ptr(pmd_page(*pmd)); 1472 } 1473 1474 static inline bool ptlock_init(struct page *page) 1475 { 1476 /* 1477 * prep_new_page() initialize page->private (and therefore page->ptl) 1478 * with 0. Make sure nobody took it in use in between. 1479 * 1480 * It can happen if arch try to use slab for page table allocation: 1481 * slab code uses page->slab_cache and page->first_page (for tail 1482 * pages), which share storage with page->ptl. 1483 */ 1484 VM_BUG_ON_PAGE(*(unsigned long *)&page->ptl, page); 1485 if (!ptlock_alloc(page)) 1486 return false; 1487 spin_lock_init(ptlock_ptr(page)); 1488 return true; 1489 } 1490 1491 /* Reset page->mapping so free_pages_check won't complain. */ 1492 static inline void pte_lock_deinit(struct page *page) 1493 { 1494 page->mapping = NULL; 1495 ptlock_free(page); 1496 } 1497 1498 #else /* !USE_SPLIT_PTE_PTLOCKS */ 1499 /* 1500 * We use mm->page_table_lock to guard all pagetable pages of the mm. 1501 */ 1502 static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd) 1503 { 1504 return &mm->page_table_lock; 1505 } 1506 static inline void ptlock_cache_init(void) {} 1507 static inline bool ptlock_init(struct page *page) { return true; } 1508 static inline void pte_lock_deinit(struct page *page) {} 1509 #endif /* USE_SPLIT_PTE_PTLOCKS */ 1510 1511 static inline void pgtable_init(void) 1512 { 1513 ptlock_cache_init(); 1514 pgtable_cache_init(); 1515 } 1516 1517 static inline bool pgtable_page_ctor(struct page *page) 1518 { 1519 inc_zone_page_state(page, NR_PAGETABLE); 1520 return ptlock_init(page); 1521 } 1522 1523 static inline void pgtable_page_dtor(struct page *page) 1524 { 1525 pte_lock_deinit(page); 1526 dec_zone_page_state(page, NR_PAGETABLE); 1527 } 1528 1529 #define pte_offset_map_lock(mm, pmd, address, ptlp) \ 1530 ({ \ 1531 spinlock_t *__ptl = pte_lockptr(mm, pmd); \ 1532 pte_t *__pte = pte_offset_map(pmd, address); \ 1533 *(ptlp) = __ptl; \ 1534 spin_lock(__ptl); \ 1535 __pte; \ 1536 }) 1537 1538 #define pte_unmap_unlock(pte, ptl) do { \ 1539 spin_unlock(ptl); \ 1540 pte_unmap(pte); \ 1541 } while (0) 1542 1543 #define pte_alloc_map(mm, vma, pmd, address) \ 1544 ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, vma, \ 1545 pmd, address))? \ 1546 NULL: pte_offset_map(pmd, address)) 1547 1548 #define pte_alloc_map_lock(mm, pmd, address, ptlp) \ 1549 ((unlikely(pmd_none(*(pmd))) && __pte_alloc(mm, NULL, \ 1550 pmd, address))? \ 1551 NULL: pte_offset_map_lock(mm, pmd, address, ptlp)) 1552 1553 #define pte_alloc_kernel(pmd, address) \ 1554 ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd, address))? \ 1555 NULL: pte_offset_kernel(pmd, address)) 1556 1557 #if USE_SPLIT_PMD_PTLOCKS 1558 1559 static struct page *pmd_to_page(pmd_t *pmd) 1560 { 1561 unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); 1562 return virt_to_page((void *)((unsigned long) pmd & mask)); 1563 } 1564 1565 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) 1566 { 1567 return ptlock_ptr(pmd_to_page(pmd)); 1568 } 1569 1570 static inline bool pgtable_pmd_page_ctor(struct page *page) 1571 { 1572 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1573 page->pmd_huge_pte = NULL; 1574 #endif 1575 return ptlock_init(page); 1576 } 1577 1578 static inline void pgtable_pmd_page_dtor(struct page *page) 1579 { 1580 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 1581 VM_BUG_ON_PAGE(page->pmd_huge_pte, page); 1582 #endif 1583 ptlock_free(page); 1584 } 1585 1586 #define pmd_huge_pte(mm, pmd) (pmd_to_page(pmd)->pmd_huge_pte) 1587 1588 #else 1589 1590 static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) 1591 { 1592 return &mm->page_table_lock; 1593 } 1594 1595 static inline bool pgtable_pmd_page_ctor(struct page *page) { return true; } 1596 static inline void pgtable_pmd_page_dtor(struct page *page) {} 1597 1598 #define pmd_huge_pte(mm, pmd) ((mm)->pmd_huge_pte) 1599 1600 #endif 1601 1602 static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd) 1603 { 1604 spinlock_t *ptl = pmd_lockptr(mm, pmd); 1605 spin_lock(ptl); 1606 return ptl; 1607 } 1608 1609 extern void free_area_init(unsigned long * zones_size); 1610 extern void free_area_init_node(int nid, unsigned long * zones_size, 1611 unsigned long zone_start_pfn, unsigned long *zholes_size); 1612 extern void free_initmem(void); 1613 1614 /* 1615 * Free reserved pages within range [PAGE_ALIGN(start), end & PAGE_MASK) 1616 * into the buddy system. The freed pages will be poisoned with pattern 1617 * "poison" if it's within range [0, UCHAR_MAX]. 1618 * Return pages freed into the buddy system. 1619 */ 1620 extern unsigned long free_reserved_area(void *start, void *end, 1621 int poison, char *s); 1622 1623 #ifdef CONFIG_HIGHMEM 1624 /* 1625 * Free a highmem page into the buddy system, adjusting totalhigh_pages 1626 * and totalram_pages. 1627 */ 1628 extern void free_highmem_page(struct page *page); 1629 #endif 1630 1631 extern void adjust_managed_page_count(struct page *page, long count); 1632 extern void mem_init_print_info(const char *str); 1633 1634 /* Free the reserved page into the buddy system, so it gets managed. */ 1635 static inline void __free_reserved_page(struct page *page) 1636 { 1637 ClearPageReserved(page); 1638 init_page_count(page); 1639 __free_page(page); 1640 } 1641 1642 static inline void free_reserved_page(struct page *page) 1643 { 1644 __free_reserved_page(page); 1645 adjust_managed_page_count(page, 1); 1646 } 1647 1648 static inline void mark_page_reserved(struct page *page) 1649 { 1650 SetPageReserved(page); 1651 adjust_managed_page_count(page, -1); 1652 } 1653 1654 /* 1655 * Default method to free all the __init memory into the buddy system. 1656 * The freed pages will be poisoned with pattern "poison" if it's within 1657 * range [0, UCHAR_MAX]. 1658 * Return pages freed into the buddy system. 1659 */ 1660 static inline unsigned long free_initmem_default(int poison) 1661 { 1662 extern char __init_begin[], __init_end[]; 1663 1664 return free_reserved_area(&__init_begin, &__init_end, 1665 poison, "unused kernel"); 1666 } 1667 1668 static inline unsigned long get_num_physpages(void) 1669 { 1670 int nid; 1671 unsigned long phys_pages = 0; 1672 1673 for_each_online_node(nid) 1674 phys_pages += node_present_pages(nid); 1675 1676 return phys_pages; 1677 } 1678 1679 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP 1680 /* 1681 * With CONFIG_HAVE_MEMBLOCK_NODE_MAP set, an architecture may initialise its 1682 * zones, allocate the backing mem_map and account for memory holes in a more 1683 * architecture independent manner. This is a substitute for creating the 1684 * zone_sizes[] and zholes_size[] arrays and passing them to 1685 * free_area_init_node() 1686 * 1687 * An architecture is expected to register range of page frames backed by 1688 * physical memory with memblock_add[_node]() before calling 1689 * free_area_init_nodes() passing in the PFN each zone ends at. At a basic 1690 * usage, an architecture is expected to do something like 1691 * 1692 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn, 1693 * max_highmem_pfn}; 1694 * for_each_valid_physical_page_range() 1695 * memblock_add_node(base, size, nid) 1696 * free_area_init_nodes(max_zone_pfns); 1697 * 1698 * free_bootmem_with_active_regions() calls free_bootmem_node() for each 1699 * registered physical page range. Similarly 1700 * sparse_memory_present_with_active_regions() calls memory_present() for 1701 * each range when SPARSEMEM is enabled. 1702 * 1703 * See mm/page_alloc.c for more information on each function exposed by 1704 * CONFIG_HAVE_MEMBLOCK_NODE_MAP. 1705 */ 1706 extern void free_area_init_nodes(unsigned long *max_zone_pfn); 1707 unsigned long node_map_pfn_alignment(void); 1708 unsigned long __absent_pages_in_range(int nid, unsigned long start_pfn, 1709 unsigned long end_pfn); 1710 extern unsigned long absent_pages_in_range(unsigned long start_pfn, 1711 unsigned long end_pfn); 1712 extern void get_pfn_range_for_nid(unsigned int nid, 1713 unsigned long *start_pfn, unsigned long *end_pfn); 1714 extern unsigned long find_min_pfn_with_active_regions(void); 1715 extern void free_bootmem_with_active_regions(int nid, 1716 unsigned long max_low_pfn); 1717 extern void sparse_memory_present_with_active_regions(int nid); 1718 1719 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ 1720 1721 #if !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) && \ 1722 !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) 1723 static inline int __early_pfn_to_nid(unsigned long pfn) 1724 { 1725 return 0; 1726 } 1727 #else 1728 /* please see mm/page_alloc.c */ 1729 extern int __meminit early_pfn_to_nid(unsigned long pfn); 1730 /* there is a per-arch backend function. */ 1731 extern int __meminit __early_pfn_to_nid(unsigned long pfn); 1732 #endif 1733 1734 extern void set_dma_reserve(unsigned long new_dma_reserve); 1735 extern void memmap_init_zone(unsigned long, int, unsigned long, 1736 unsigned long, enum memmap_context); 1737 extern void setup_per_zone_wmarks(void); 1738 extern int __meminit init_per_zone_wmark_min(void); 1739 extern void mem_init(void); 1740 extern void __init mmap_init(void); 1741 extern void show_mem(unsigned int flags); 1742 extern void si_meminfo(struct sysinfo * val); 1743 extern void si_meminfo_node(struct sysinfo *val, int nid); 1744 1745 extern __printf(3, 4) 1746 void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...); 1747 1748 extern void setup_per_cpu_pageset(void); 1749 1750 extern void zone_pcp_update(struct zone *zone); 1751 extern void zone_pcp_reset(struct zone *zone); 1752 1753 /* page_alloc.c */ 1754 extern int min_free_kbytes; 1755 1756 /* nommu.c */ 1757 extern atomic_long_t mmap_pages_allocated; 1758 extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t); 1759 1760 /* interval_tree.c */ 1761 void vma_interval_tree_insert(struct vm_area_struct *node, 1762 struct rb_root *root); 1763 void vma_interval_tree_insert_after(struct vm_area_struct *node, 1764 struct vm_area_struct *prev, 1765 struct rb_root *root); 1766 void vma_interval_tree_remove(struct vm_area_struct *node, 1767 struct rb_root *root); 1768 struct vm_area_struct *vma_interval_tree_iter_first(struct rb_root *root, 1769 unsigned long start, unsigned long last); 1770 struct vm_area_struct *vma_interval_tree_iter_next(struct vm_area_struct *node, 1771 unsigned long start, unsigned long last); 1772 1773 #define vma_interval_tree_foreach(vma, root, start, last) \ 1774 for (vma = vma_interval_tree_iter_first(root, start, last); \ 1775 vma; vma = vma_interval_tree_iter_next(vma, start, last)) 1776 1777 void anon_vma_interval_tree_insert(struct anon_vma_chain *node, 1778 struct rb_root *root); 1779 void anon_vma_interval_tree_remove(struct anon_vma_chain *node, 1780 struct rb_root *root); 1781 struct anon_vma_chain *anon_vma_interval_tree_iter_first( 1782 struct rb_root *root, unsigned long start, unsigned long last); 1783 struct anon_vma_chain *anon_vma_interval_tree_iter_next( 1784 struct anon_vma_chain *node, unsigned long start, unsigned long last); 1785 #ifdef CONFIG_DEBUG_VM_RB 1786 void anon_vma_interval_tree_verify(struct anon_vma_chain *node); 1787 #endif 1788 1789 #define anon_vma_interval_tree_foreach(avc, root, start, last) \ 1790 for (avc = anon_vma_interval_tree_iter_first(root, start, last); \ 1791 avc; avc = anon_vma_interval_tree_iter_next(avc, start, last)) 1792 1793 /* mmap.c */ 1794 extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin); 1795 extern int vma_adjust(struct vm_area_struct *vma, unsigned long start, 1796 unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert); 1797 extern struct vm_area_struct *vma_merge(struct mm_struct *, 1798 struct vm_area_struct *prev, unsigned long addr, unsigned long end, 1799 unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t, 1800 struct mempolicy *); 1801 extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *); 1802 extern int split_vma(struct mm_struct *, 1803 struct vm_area_struct *, unsigned long addr, int new_below); 1804 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *); 1805 extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *, 1806 struct rb_node **, struct rb_node *); 1807 extern void unlink_file_vma(struct vm_area_struct *); 1808 extern struct vm_area_struct *copy_vma(struct vm_area_struct **, 1809 unsigned long addr, unsigned long len, pgoff_t pgoff, 1810 bool *need_rmap_locks); 1811 extern void exit_mmap(struct mm_struct *); 1812 1813 static inline int check_data_rlimit(unsigned long rlim, 1814 unsigned long new, 1815 unsigned long start, 1816 unsigned long end_data, 1817 unsigned long start_data) 1818 { 1819 if (rlim < RLIM_INFINITY) { 1820 if (((new - start) + (end_data - start_data)) > rlim) 1821 return -ENOSPC; 1822 } 1823 1824 return 0; 1825 } 1826 1827 extern int mm_take_all_locks(struct mm_struct *mm); 1828 extern void mm_drop_all_locks(struct mm_struct *mm); 1829 1830 extern void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file); 1831 extern struct file *get_mm_exe_file(struct mm_struct *mm); 1832 1833 extern int may_expand_vm(struct mm_struct *mm, unsigned long npages); 1834 extern struct vm_area_struct *_install_special_mapping(struct mm_struct *mm, 1835 unsigned long addr, unsigned long len, 1836 unsigned long flags, 1837 const struct vm_special_mapping *spec); 1838 /* This is an obsolete alternative to _install_special_mapping. */ 1839 extern int install_special_mapping(struct mm_struct *mm, 1840 unsigned long addr, unsigned long len, 1841 unsigned long flags, struct page **pages); 1842 1843 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); 1844 1845 extern unsigned long mmap_region(struct file *file, unsigned long addr, 1846 unsigned long len, vm_flags_t vm_flags, unsigned long pgoff); 1847 extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, 1848 unsigned long len, unsigned long prot, unsigned long flags, 1849 unsigned long pgoff, unsigned long *populate); 1850 extern int do_munmap(struct mm_struct *, unsigned long, size_t); 1851 1852 #ifdef CONFIG_MMU 1853 extern int __mm_populate(unsigned long addr, unsigned long len, 1854 int ignore_errors); 1855 static inline void mm_populate(unsigned long addr, unsigned long len) 1856 { 1857 /* Ignore errors */ 1858 (void) __mm_populate(addr, len, 1); 1859 } 1860 #else 1861 static inline void mm_populate(unsigned long addr, unsigned long len) {} 1862 #endif 1863 1864 /* These take the mm semaphore themselves */ 1865 extern unsigned long vm_brk(unsigned long, unsigned long); 1866 extern int vm_munmap(unsigned long, size_t); 1867 extern unsigned long vm_mmap(struct file *, unsigned long, 1868 unsigned long, unsigned long, 1869 unsigned long, unsigned long); 1870 1871 struct vm_unmapped_area_info { 1872 #define VM_UNMAPPED_AREA_TOPDOWN 1 1873 unsigned long flags; 1874 unsigned long length; 1875 unsigned long low_limit; 1876 unsigned long high_limit; 1877 unsigned long align_mask; 1878 unsigned long align_offset; 1879 }; 1880 1881 extern unsigned long unmapped_area(struct vm_unmapped_area_info *info); 1882 extern unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info); 1883 1884 /* 1885 * Search for an unmapped address range. 1886 * 1887 * We are looking for a range that: 1888 * - does not intersect with any VMA; 1889 * - is contained within the [low_limit, high_limit) interval; 1890 * - is at least the desired size. 1891 * - satisfies (begin_addr & align_mask) == (align_offset & align_mask) 1892 */ 1893 static inline unsigned long 1894 vm_unmapped_area(struct vm_unmapped_area_info *info) 1895 { 1896 if (info->flags & VM_UNMAPPED_AREA_TOPDOWN) 1897 return unmapped_area_topdown(info); 1898 else 1899 return unmapped_area(info); 1900 } 1901 1902 /* truncate.c */ 1903 extern void truncate_inode_pages(struct address_space *, loff_t); 1904 extern void truncate_inode_pages_range(struct address_space *, 1905 loff_t lstart, loff_t lend); 1906 extern void truncate_inode_pages_final(struct address_space *); 1907 1908 /* generic vm_area_ops exported for stackable file systems */ 1909 extern int filemap_fault(struct vm_area_struct *, struct vm_fault *); 1910 extern void filemap_map_pages(struct vm_area_struct *vma, struct vm_fault *vmf); 1911 extern int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf); 1912 1913 /* mm/page-writeback.c */ 1914 int write_one_page(struct page *page, int wait); 1915 void task_dirty_inc(struct task_struct *tsk); 1916 1917 /* readahead.c */ 1918 #define VM_MAX_READAHEAD 128 /* kbytes */ 1919 #define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */ 1920 1921 int force_page_cache_readahead(struct address_space *mapping, struct file *filp, 1922 pgoff_t offset, unsigned long nr_to_read); 1923 1924 void page_cache_sync_readahead(struct address_space *mapping, 1925 struct file_ra_state *ra, 1926 struct file *filp, 1927 pgoff_t offset, 1928 unsigned long size); 1929 1930 void page_cache_async_readahead(struct address_space *mapping, 1931 struct file_ra_state *ra, 1932 struct file *filp, 1933 struct page *pg, 1934 pgoff_t offset, 1935 unsigned long size); 1936 1937 unsigned long max_sane_readahead(unsigned long nr); 1938 1939 /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */ 1940 extern int expand_stack(struct vm_area_struct *vma, unsigned long address); 1941 1942 /* CONFIG_STACK_GROWSUP still needs to to grow downwards at some places */ 1943 extern int expand_downwards(struct vm_area_struct *vma, 1944 unsigned long address); 1945 #if VM_GROWSUP 1946 extern int expand_upwards(struct vm_area_struct *vma, unsigned long address); 1947 #else 1948 #define expand_upwards(vma, address) (0) 1949 #endif 1950 1951 /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */ 1952 extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr); 1953 extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr, 1954 struct vm_area_struct **pprev); 1955 1956 /* Look up the first VMA which intersects the interval start_addr..end_addr-1, 1957 NULL if none. Assume start_addr < end_addr. */ 1958 static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr) 1959 { 1960 struct vm_area_struct * vma = find_vma(mm,start_addr); 1961 1962 if (vma && end_addr <= vma->vm_start) 1963 vma = NULL; 1964 return vma; 1965 } 1966 1967 static inline unsigned long vma_pages(struct vm_area_struct *vma) 1968 { 1969 return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; 1970 } 1971 1972 /* Look up the first VMA which exactly match the interval vm_start ... vm_end */ 1973 static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm, 1974 unsigned long vm_start, unsigned long vm_end) 1975 { 1976 struct vm_area_struct *vma = find_vma(mm, vm_start); 1977 1978 if (vma && (vma->vm_start != vm_start || vma->vm_end != vm_end)) 1979 vma = NULL; 1980 1981 return vma; 1982 } 1983 1984 #ifdef CONFIG_MMU 1985 pgprot_t vm_get_page_prot(unsigned long vm_flags); 1986 void vma_set_page_prot(struct vm_area_struct *vma); 1987 #else 1988 static inline pgprot_t vm_get_page_prot(unsigned long vm_flags) 1989 { 1990 return __pgprot(0); 1991 } 1992 static inline void vma_set_page_prot(struct vm_area_struct *vma) 1993 { 1994 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); 1995 } 1996 #endif 1997 1998 #ifdef CONFIG_NUMA_BALANCING 1999 unsigned long change_prot_numa(struct vm_area_struct *vma, 2000 unsigned long start, unsigned long end); 2001 #endif 2002 2003 struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr); 2004 int remap_pfn_range(struct vm_area_struct *, unsigned long addr, 2005 unsigned long pfn, unsigned long size, pgprot_t); 2006 int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *); 2007 int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr, 2008 unsigned long pfn); 2009 int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr, 2010 unsigned long pfn); 2011 int vm_iomap_memory(struct vm_area_struct *vma, phys_addr_t start, unsigned long len); 2012 2013 2014 struct page *follow_page_mask(struct vm_area_struct *vma, 2015 unsigned long address, unsigned int foll_flags, 2016 unsigned int *page_mask); 2017 2018 static inline struct page *follow_page(struct vm_area_struct *vma, 2019 unsigned long address, unsigned int foll_flags) 2020 { 2021 unsigned int unused_page_mask; 2022 return follow_page_mask(vma, address, foll_flags, &unused_page_mask); 2023 } 2024 2025 #define FOLL_WRITE 0x01 /* check pte is writable */ 2026 #define FOLL_TOUCH 0x02 /* mark page accessed */ 2027 #define FOLL_GET 0x04 /* do get_page on page */ 2028 #define FOLL_DUMP 0x08 /* give error on hole if it would be zero */ 2029 #define FOLL_FORCE 0x10 /* get_user_pages read/write w/o permission */ 2030 #define FOLL_NOWAIT 0x20 /* if a disk transfer is needed, start the IO 2031 * and return without waiting upon it */ 2032 #define FOLL_POPULATE 0x40 /* fault in page */ 2033 #define FOLL_SPLIT 0x80 /* don't return transhuge pages, split them */ 2034 #define FOLL_HWPOISON 0x100 /* check page is hwpoisoned */ 2035 #define FOLL_NUMA 0x200 /* force NUMA hinting page fault */ 2036 #define FOLL_MIGRATION 0x400 /* wait for page to replace migration entry */ 2037 #define FOLL_TRIED 0x800 /* a retry, previous pass started an IO */ 2038 2039 typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr, 2040 void *data); 2041 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address, 2042 unsigned long size, pte_fn_t fn, void *data); 2043 2044 #ifdef CONFIG_PROC_FS 2045 void vm_stat_account(struct mm_struct *, unsigned long, struct file *, long); 2046 #else 2047 static inline void vm_stat_account(struct mm_struct *mm, 2048 unsigned long flags, struct file *file, long pages) 2049 { 2050 mm->total_vm += pages; 2051 } 2052 #endif /* CONFIG_PROC_FS */ 2053 2054 #ifdef CONFIG_DEBUG_PAGEALLOC 2055 extern bool _debug_pagealloc_enabled; 2056 extern void __kernel_map_pages(struct page *page, int numpages, int enable); 2057 2058 static inline bool debug_pagealloc_enabled(void) 2059 { 2060 return _debug_pagealloc_enabled; 2061 } 2062 2063 static inline void 2064 kernel_map_pages(struct page *page, int numpages, int enable) 2065 { 2066 if (!debug_pagealloc_enabled()) 2067 return; 2068 2069 __kernel_map_pages(page, numpages, enable); 2070 } 2071 #ifdef CONFIG_HIBERNATION 2072 extern bool kernel_page_present(struct page *page); 2073 #endif /* CONFIG_HIBERNATION */ 2074 #else 2075 static inline void 2076 kernel_map_pages(struct page *page, int numpages, int enable) {} 2077 #ifdef CONFIG_HIBERNATION 2078 static inline bool kernel_page_present(struct page *page) { return true; } 2079 #endif /* CONFIG_HIBERNATION */ 2080 #endif 2081 2082 #ifdef __HAVE_ARCH_GATE_AREA 2083 extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm); 2084 extern int in_gate_area_no_mm(unsigned long addr); 2085 extern int in_gate_area(struct mm_struct *mm, unsigned long addr); 2086 #else 2087 static inline struct vm_area_struct *get_gate_vma(struct mm_struct *mm) 2088 { 2089 return NULL; 2090 } 2091 static inline int in_gate_area_no_mm(unsigned long addr) { return 0; } 2092 static inline int in_gate_area(struct mm_struct *mm, unsigned long addr) 2093 { 2094 return 0; 2095 } 2096 #endif /* __HAVE_ARCH_GATE_AREA */ 2097 2098 #ifdef CONFIG_SYSCTL 2099 extern int sysctl_drop_caches; 2100 int drop_caches_sysctl_handler(struct ctl_table *, int, 2101 void __user *, size_t *, loff_t *); 2102 #endif 2103 2104 void drop_slab(void); 2105 void drop_slab_node(int nid); 2106 2107 #ifndef CONFIG_MMU 2108 #define randomize_va_space 0 2109 #else 2110 extern int randomize_va_space; 2111 #endif 2112 2113 const char * arch_vma_name(struct vm_area_struct *vma); 2114 void print_vma_addr(char *prefix, unsigned long rip); 2115 2116 void sparse_mem_maps_populate_node(struct page **map_map, 2117 unsigned long pnum_begin, 2118 unsigned long pnum_end, 2119 unsigned long map_count, 2120 int nodeid); 2121 2122 struct page *sparse_mem_map_populate(unsigned long pnum, int nid); 2123 pgd_t *vmemmap_pgd_populate(unsigned long addr, int node); 2124 pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node); 2125 pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node); 2126 pte_t *vmemmap_pte_populate(pmd_t *pmd, unsigned long addr, int node); 2127 void *vmemmap_alloc_block(unsigned long size, int node); 2128 void *vmemmap_alloc_block_buf(unsigned long size, int node); 2129 void vmemmap_verify(pte_t *, int, unsigned long, unsigned long); 2130 int vmemmap_populate_basepages(unsigned long start, unsigned long end, 2131 int node); 2132 int vmemmap_populate(unsigned long start, unsigned long end, int node); 2133 void vmemmap_populate_print_last(void); 2134 #ifdef CONFIG_MEMORY_HOTPLUG 2135 void vmemmap_free(unsigned long start, unsigned long end); 2136 #endif 2137 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map, 2138 unsigned long size); 2139 2140 enum mf_flags { 2141 MF_COUNT_INCREASED = 1 << 0, 2142 MF_ACTION_REQUIRED = 1 << 1, 2143 MF_MUST_KILL = 1 << 2, 2144 MF_SOFT_OFFLINE = 1 << 3, 2145 }; 2146 extern int memory_failure(unsigned long pfn, int trapno, int flags); 2147 extern void memory_failure_queue(unsigned long pfn, int trapno, int flags); 2148 extern int unpoison_memory(unsigned long pfn); 2149 extern int sysctl_memory_failure_early_kill; 2150 extern int sysctl_memory_failure_recovery; 2151 extern void shake_page(struct page *p, int access); 2152 extern atomic_long_t num_poisoned_pages; 2153 extern int soft_offline_page(struct page *page, int flags); 2154 2155 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLBFS) 2156 extern void clear_huge_page(struct page *page, 2157 unsigned long addr, 2158 unsigned int pages_per_huge_page); 2159 extern void copy_user_huge_page(struct page *dst, struct page *src, 2160 unsigned long addr, struct vm_area_struct *vma, 2161 unsigned int pages_per_huge_page); 2162 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */ 2163 2164 extern struct page_ext_operations debug_guardpage_ops; 2165 extern struct page_ext_operations page_poisoning_ops; 2166 2167 #ifdef CONFIG_DEBUG_PAGEALLOC 2168 extern unsigned int _debug_guardpage_minorder; 2169 extern bool _debug_guardpage_enabled; 2170 2171 static inline unsigned int debug_guardpage_minorder(void) 2172 { 2173 return _debug_guardpage_minorder; 2174 } 2175 2176 static inline bool debug_guardpage_enabled(void) 2177 { 2178 return _debug_guardpage_enabled; 2179 } 2180 2181 static inline bool page_is_guard(struct page *page) 2182 { 2183 struct page_ext *page_ext; 2184 2185 if (!debug_guardpage_enabled()) 2186 return false; 2187 2188 page_ext = lookup_page_ext(page); 2189 return test_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags); 2190 } 2191 #else 2192 static inline unsigned int debug_guardpage_minorder(void) { return 0; } 2193 static inline bool debug_guardpage_enabled(void) { return false; } 2194 static inline bool page_is_guard(struct page *page) { return false; } 2195 #endif /* CONFIG_DEBUG_PAGEALLOC */ 2196 2197 #if MAX_NUMNODES > 1 2198 void __init setup_nr_node_ids(void); 2199 #else 2200 static inline void setup_nr_node_ids(void) {} 2201 #endif 2202 2203 #endif /* __KERNEL__ */ 2204 #endif /* _LINUX_MM_H */ 2205