1 #ifndef _LINUX_MM_H 2 #define _LINUX_MM_H 3 4 #include <linux/errno.h> 5 6 #ifdef __KERNEL__ 7 8 #include <linux/gfp.h> 9 #include <linux/list.h> 10 #include <linux/mmzone.h> 11 #include <linux/rbtree.h> 12 #include <linux/prio_tree.h> 13 #include <linux/mutex.h> 14 #include <linux/debug_locks.h> 15 #include <linux/backing-dev.h> 16 #include <linux/mm_types.h> 17 18 struct mempolicy; 19 struct anon_vma; 20 struct file_ra_state; 21 struct user_struct; 22 struct writeback_control; 23 24 #ifndef CONFIG_DISCONTIGMEM /* Don't use mapnrs, do it properly */ 25 extern unsigned long max_mapnr; 26 #endif 27 28 extern unsigned long num_physpages; 29 extern void * high_memory; 30 extern int page_cluster; 31 32 #ifdef CONFIG_SYSCTL 33 extern int sysctl_legacy_va_layout; 34 #else 35 #define sysctl_legacy_va_layout 0 36 #endif 37 38 #include <asm/page.h> 39 #include <asm/pgtable.h> 40 #include <asm/processor.h> 41 42 #define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n)) 43 44 /* 45 * Linux kernel virtual memory manager primitives. 46 * The idea being to have a "virtual" mm in the same way 47 * we have a virtual fs - giving a cleaner interface to the 48 * mm details, and allowing different kinds of memory mappings 49 * (from shared memory to executable loading to arbitrary 50 * mmap() functions). 51 */ 52 53 /* 54 * This struct defines a memory VMM memory area. There is one of these 55 * per VM-area/task. A VM area is any part of the process virtual memory 56 * space that has a special rule for the page-fault handlers (ie a shared 57 * library, the executable area etc). 58 */ 59 struct vm_area_struct { 60 struct mm_struct * vm_mm; /* The address space we belong to. */ 61 unsigned long vm_start; /* Our start address within vm_mm. */ 62 unsigned long vm_end; /* The first byte after our end address 63 within vm_mm. */ 64 65 /* linked list of VM areas per task, sorted by address */ 66 struct vm_area_struct *vm_next; 67 68 pgprot_t vm_page_prot; /* Access permissions of this VMA. */ 69 unsigned long vm_flags; /* Flags, listed below. */ 70 71 struct rb_node vm_rb; 72 73 /* 74 * For areas with an address space and backing store, 75 * linkage into the address_space->i_mmap prio tree, or 76 * linkage to the list of like vmas hanging off its node, or 77 * linkage of vma in the address_space->i_mmap_nonlinear list. 78 */ 79 union { 80 struct { 81 struct list_head list; 82 void *parent; /* aligns with prio_tree_node parent */ 83 struct vm_area_struct *head; 84 } vm_set; 85 86 struct raw_prio_tree_node prio_tree_node; 87 } shared; 88 89 /* 90 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma 91 * list, after a COW of one of the file pages. A MAP_SHARED vma 92 * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack 93 * or brk vma (with NULL file) can only be in an anon_vma list. 94 */ 95 struct list_head anon_vma_node; /* Serialized by anon_vma->lock */ 96 struct anon_vma *anon_vma; /* Serialized by page_table_lock */ 97 98 /* Function pointers to deal with this struct. */ 99 struct vm_operations_struct * vm_ops; 100 101 /* Information about our backing store: */ 102 unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE 103 units, *not* PAGE_CACHE_SIZE */ 104 struct file * vm_file; /* File we map to (can be NULL). */ 105 void * vm_private_data; /* was vm_pte (shared mem) */ 106 unsigned long vm_truncate_count;/* truncate_count or restart_addr */ 107 108 #ifndef CONFIG_MMU 109 atomic_t vm_usage; /* refcount (VMAs shared if !MMU) */ 110 #endif 111 #ifdef CONFIG_NUMA 112 struct mempolicy *vm_policy; /* NUMA policy for the VMA */ 113 #endif 114 }; 115 116 extern struct kmem_cache *vm_area_cachep; 117 118 /* 119 * This struct defines the per-mm list of VMAs for uClinux. If CONFIG_MMU is 120 * disabled, then there's a single shared list of VMAs maintained by the 121 * system, and mm's subscribe to these individually 122 */ 123 struct vm_list_struct { 124 struct vm_list_struct *next; 125 struct vm_area_struct *vma; 126 }; 127 128 #ifndef CONFIG_MMU 129 extern struct rb_root nommu_vma_tree; 130 extern struct rw_semaphore nommu_vma_sem; 131 132 extern unsigned int kobjsize(const void *objp); 133 #endif 134 135 /* 136 * vm_flags.. 137 */ 138 #define VM_READ 0x00000001 /* currently active flags */ 139 #define VM_WRITE 0x00000002 140 #define VM_EXEC 0x00000004 141 #define VM_SHARED 0x00000008 142 143 /* mprotect() hardcodes VM_MAYREAD >> 4 == VM_READ, and so for r/w/x bits. */ 144 #define VM_MAYREAD 0x00000010 /* limits for mprotect() etc */ 145 #define VM_MAYWRITE 0x00000020 146 #define VM_MAYEXEC 0x00000040 147 #define VM_MAYSHARE 0x00000080 148 149 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */ 150 #define VM_GROWSUP 0x00000200 151 #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */ 152 #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */ 153 154 #define VM_EXECUTABLE 0x00001000 155 #define VM_LOCKED 0x00002000 156 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */ 157 158 /* Used by sys_madvise() */ 159 #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ 160 #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */ 161 162 #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ 163 #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ 164 #define VM_RESERVED 0x00080000 /* Count as reserved_vm like IO */ 165 #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ 166 #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ 167 #define VM_NONLINEAR 0x00800000 /* Is non-linear (remap_file_pages) */ 168 #define VM_MAPPED_COPY 0x01000000 /* T if mapped copy of data (nommu mmap) */ 169 #define VM_INSERTPAGE 0x02000000 /* The vma has had "vm_insert_page()" done on it */ 170 #define VM_ALWAYSDUMP 0x04000000 /* Always include in core dumps */ 171 172 #define VM_CAN_NONLINEAR 0x08000000 /* Has ->fault & does nonlinear pages */ 173 174 #ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */ 175 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS 176 #endif 177 178 #ifdef CONFIG_STACK_GROWSUP 179 #define VM_STACK_FLAGS (VM_GROWSUP | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 180 #else 181 #define VM_STACK_FLAGS (VM_GROWSDOWN | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 182 #endif 183 184 #define VM_READHINTMASK (VM_SEQ_READ | VM_RAND_READ) 185 #define VM_ClearReadHint(v) (v)->vm_flags &= ~VM_READHINTMASK 186 #define VM_NormalReadHint(v) (!((v)->vm_flags & VM_READHINTMASK)) 187 #define VM_SequentialReadHint(v) ((v)->vm_flags & VM_SEQ_READ) 188 #define VM_RandomReadHint(v) ((v)->vm_flags & VM_RAND_READ) 189 190 /* 191 * mapping from the currently active vm_flags protection bits (the 192 * low four bits) to a page protection mask.. 193 */ 194 extern pgprot_t protection_map[16]; 195 196 #define FAULT_FLAG_WRITE 0x01 /* Fault was a write access */ 197 #define FAULT_FLAG_NONLINEAR 0x02 /* Fault was via a nonlinear mapping */ 198 199 200 /* 201 * vm_fault is filled by the the pagefault handler and passed to the vma's 202 * ->fault function. The vma's ->fault is responsible for returning a bitmask 203 * of VM_FAULT_xxx flags that give details about how the fault was handled. 204 * 205 * pgoff should be used in favour of virtual_address, if possible. If pgoff 206 * is used, one may set VM_CAN_NONLINEAR in the vma->vm_flags to get nonlinear 207 * mapping support. 208 */ 209 struct vm_fault { 210 unsigned int flags; /* FAULT_FLAG_xxx flags */ 211 pgoff_t pgoff; /* Logical page offset based on vma */ 212 void __user *virtual_address; /* Faulting virtual address */ 213 214 struct page *page; /* ->fault handlers should return a 215 * page here, unless VM_FAULT_NOPAGE 216 * is set (which is also implied by 217 * VM_FAULT_ERROR). 218 */ 219 }; 220 221 /* 222 * These are the virtual MM functions - opening of an area, closing and 223 * unmapping it (needed to keep files on disk up-to-date etc), pointer 224 * to the functions called when a no-page or a wp-page exception occurs. 225 */ 226 struct vm_operations_struct { 227 void (*open)(struct vm_area_struct * area); 228 void (*close)(struct vm_area_struct * area); 229 int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf); 230 struct page *(*nopage)(struct vm_area_struct *area, 231 unsigned long address, int *type); 232 unsigned long (*nopfn)(struct vm_area_struct *area, 233 unsigned long address); 234 235 /* notification that a previously read-only page is about to become 236 * writable, if an error is returned it will cause a SIGBUS */ 237 int (*page_mkwrite)(struct vm_area_struct *vma, struct page *page); 238 #ifdef CONFIG_NUMA 239 int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); 240 struct mempolicy *(*get_policy)(struct vm_area_struct *vma, 241 unsigned long addr); 242 int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from, 243 const nodemask_t *to, unsigned long flags); 244 #endif 245 }; 246 247 struct mmu_gather; 248 struct inode; 249 250 #define page_private(page) ((page)->private) 251 #define set_page_private(page, v) ((page)->private = (v)) 252 253 /* 254 * FIXME: take this include out, include page-flags.h in 255 * files which need it (119 of them) 256 */ 257 #include <linux/page-flags.h> 258 259 #ifdef CONFIG_DEBUG_VM 260 #define VM_BUG_ON(cond) BUG_ON(cond) 261 #else 262 #define VM_BUG_ON(condition) do { } while(0) 263 #endif 264 265 /* 266 * Methods to modify the page usage count. 267 * 268 * What counts for a page usage: 269 * - cache mapping (page->mapping) 270 * - private data (page->private) 271 * - page mapped in a task's page tables, each mapping 272 * is counted separately 273 * 274 * Also, many kernel routines increase the page count before a critical 275 * routine so they can be sure the page doesn't go away from under them. 276 */ 277 278 /* 279 * Drop a ref, return true if the refcount fell to zero (the page has no users) 280 */ 281 static inline int put_page_testzero(struct page *page) 282 { 283 VM_BUG_ON(atomic_read(&page->_count) == 0); 284 return atomic_dec_and_test(&page->_count); 285 } 286 287 /* 288 * Try to grab a ref unless the page has a refcount of zero, return false if 289 * that is the case. 290 */ 291 static inline int get_page_unless_zero(struct page *page) 292 { 293 VM_BUG_ON(PageCompound(page)); 294 return atomic_inc_not_zero(&page->_count); 295 } 296 297 static inline struct page *compound_head(struct page *page) 298 { 299 if (unlikely(PageTail(page))) 300 return page->first_page; 301 return page; 302 } 303 304 static inline int page_count(struct page *page) 305 { 306 return atomic_read(&compound_head(page)->_count); 307 } 308 309 static inline void get_page(struct page *page) 310 { 311 page = compound_head(page); 312 VM_BUG_ON(atomic_read(&page->_count) == 0); 313 atomic_inc(&page->_count); 314 } 315 316 static inline struct page *virt_to_head_page(const void *x) 317 { 318 struct page *page = virt_to_page(x); 319 return compound_head(page); 320 } 321 322 /* 323 * Setup the page count before being freed into the page allocator for 324 * the first time (boot or memory hotplug) 325 */ 326 static inline void init_page_count(struct page *page) 327 { 328 atomic_set(&page->_count, 1); 329 } 330 331 void put_page(struct page *page); 332 void put_pages_list(struct list_head *pages); 333 334 void split_page(struct page *page, unsigned int order); 335 336 /* 337 * Compound pages have a destructor function. Provide a 338 * prototype for that function and accessor functions. 339 * These are _only_ valid on the head of a PG_compound page. 340 */ 341 typedef void compound_page_dtor(struct page *); 342 343 static inline void set_compound_page_dtor(struct page *page, 344 compound_page_dtor *dtor) 345 { 346 page[1].lru.next = (void *)dtor; 347 } 348 349 static inline compound_page_dtor *get_compound_page_dtor(struct page *page) 350 { 351 return (compound_page_dtor *)page[1].lru.next; 352 } 353 354 static inline int compound_order(struct page *page) 355 { 356 if (!PageHead(page)) 357 return 0; 358 return (unsigned long)page[1].lru.prev; 359 } 360 361 static inline void set_compound_order(struct page *page, unsigned long order) 362 { 363 page[1].lru.prev = (void *)order; 364 } 365 366 /* 367 * Multiple processes may "see" the same page. E.g. for untouched 368 * mappings of /dev/null, all processes see the same page full of 369 * zeroes, and text pages of executables and shared libraries have 370 * only one copy in memory, at most, normally. 371 * 372 * For the non-reserved pages, page_count(page) denotes a reference count. 373 * page_count() == 0 means the page is free. page->lru is then used for 374 * freelist management in the buddy allocator. 375 * page_count() > 0 means the page has been allocated. 376 * 377 * Pages are allocated by the slab allocator in order to provide memory 378 * to kmalloc and kmem_cache_alloc. In this case, the management of the 379 * page, and the fields in 'struct page' are the responsibility of mm/slab.c 380 * unless a particular usage is carefully commented. (the responsibility of 381 * freeing the kmalloc memory is the caller's, of course). 382 * 383 * A page may be used by anyone else who does a __get_free_page(). 384 * In this case, page_count still tracks the references, and should only 385 * be used through the normal accessor functions. The top bits of page->flags 386 * and page->virtual store page management information, but all other fields 387 * are unused and could be used privately, carefully. The management of this 388 * page is the responsibility of the one who allocated it, and those who have 389 * subsequently been given references to it. 390 * 391 * The other pages (we may call them "pagecache pages") are completely 392 * managed by the Linux memory manager: I/O, buffers, swapping etc. 393 * The following discussion applies only to them. 394 * 395 * A pagecache page contains an opaque `private' member, which belongs to the 396 * page's address_space. Usually, this is the address of a circular list of 397 * the page's disk buffers. PG_private must be set to tell the VM to call 398 * into the filesystem to release these pages. 399 * 400 * A page may belong to an inode's memory mapping. In this case, page->mapping 401 * is the pointer to the inode, and page->index is the file offset of the page, 402 * in units of PAGE_CACHE_SIZE. 403 * 404 * If pagecache pages are not associated with an inode, they are said to be 405 * anonymous pages. These may become associated with the swapcache, and in that 406 * case PG_swapcache is set, and page->private is an offset into the swapcache. 407 * 408 * In either case (swapcache or inode backed), the pagecache itself holds one 409 * reference to the page. Setting PG_private should also increment the 410 * refcount. The each user mapping also has a reference to the page. 411 * 412 * The pagecache pages are stored in a per-mapping radix tree, which is 413 * rooted at mapping->page_tree, and indexed by offset. 414 * Where 2.4 and early 2.6 kernels kept dirty/clean pages in per-address_space 415 * lists, we instead now tag pages as dirty/writeback in the radix tree. 416 * 417 * All pagecache pages may be subject to I/O: 418 * - inode pages may need to be read from disk, 419 * - inode pages which have been modified and are MAP_SHARED may need 420 * to be written back to the inode on disk, 421 * - anonymous pages (including MAP_PRIVATE file mappings) which have been 422 * modified may need to be swapped out to swap space and (later) to be read 423 * back into memory. 424 */ 425 426 /* 427 * The zone field is never updated after free_area_init_core() 428 * sets it, so none of the operations on it need to be atomic. 429 */ 430 431 432 /* 433 * page->flags layout: 434 * 435 * There are three possibilities for how page->flags get 436 * laid out. The first is for the normal case, without 437 * sparsemem. The second is for sparsemem when there is 438 * plenty of space for node and section. The last is when 439 * we have run out of space and have to fall back to an 440 * alternate (slower) way of determining the node. 441 * 442 * No sparsemem: | NODE | ZONE | ... | FLAGS | 443 * with space for node: | SECTION | NODE | ZONE | ... | FLAGS | 444 * no space for node: | SECTION | ZONE | ... | FLAGS | 445 */ 446 #ifdef CONFIG_SPARSEMEM 447 #define SECTIONS_WIDTH SECTIONS_SHIFT 448 #else 449 #define SECTIONS_WIDTH 0 450 #endif 451 452 #define ZONES_WIDTH ZONES_SHIFT 453 454 #if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT <= FLAGS_RESERVED 455 #define NODES_WIDTH NODES_SHIFT 456 #else 457 #define NODES_WIDTH 0 458 #endif 459 460 /* Page flags: | [SECTION] | [NODE] | ZONE | ... | FLAGS | */ 461 #define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH) 462 #define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH) 463 #define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH) 464 465 /* 466 * We are going to use the flags for the page to node mapping if its in 467 * there. This includes the case where there is no node, so it is implicit. 468 */ 469 #if !(NODES_WIDTH > 0 || NODES_SHIFT == 0) 470 #define NODE_NOT_IN_PAGE_FLAGS 471 #endif 472 473 #ifndef PFN_SECTION_SHIFT 474 #define PFN_SECTION_SHIFT 0 475 #endif 476 477 /* 478 * Define the bit shifts to access each section. For non-existant 479 * sections we define the shift as 0; that plus a 0 mask ensures 480 * the compiler will optimise away reference to them. 481 */ 482 #define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0)) 483 #define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0)) 484 #define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0)) 485 486 /* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allcator */ 487 #ifdef NODE_NOT_IN_PAGEFLAGS 488 #define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT) 489 #define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF)? \ 490 SECTIONS_PGOFF : ZONES_PGOFF) 491 #else 492 #define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT) 493 #define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF)? \ 494 NODES_PGOFF : ZONES_PGOFF) 495 #endif 496 497 #define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0)) 498 499 #if SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED 500 #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > FLAGS_RESERVED 501 #endif 502 503 #define ZONES_MASK ((1UL << ZONES_WIDTH) - 1) 504 #define NODES_MASK ((1UL << NODES_WIDTH) - 1) 505 #define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1) 506 #define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1) 507 508 static inline enum zone_type page_zonenum(struct page *page) 509 { 510 return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK; 511 } 512 513 /* 514 * The identification function is only used by the buddy allocator for 515 * determining if two pages could be buddies. We are not really 516 * identifying a zone since we could be using a the section number 517 * id if we have not node id available in page flags. 518 * We guarantee only that it will return the same value for two 519 * combinable pages in a zone. 520 */ 521 static inline int page_zone_id(struct page *page) 522 { 523 return (page->flags >> ZONEID_PGSHIFT) & ZONEID_MASK; 524 } 525 526 static inline int zone_to_nid(struct zone *zone) 527 { 528 #ifdef CONFIG_NUMA 529 return zone->node; 530 #else 531 return 0; 532 #endif 533 } 534 535 #ifdef NODE_NOT_IN_PAGE_FLAGS 536 extern int page_to_nid(struct page *page); 537 #else 538 static inline int page_to_nid(struct page *page) 539 { 540 return (page->flags >> NODES_PGSHIFT) & NODES_MASK; 541 } 542 #endif 543 544 static inline struct zone *page_zone(struct page *page) 545 { 546 return &NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)]; 547 } 548 549 static inline unsigned long page_to_section(struct page *page) 550 { 551 return (page->flags >> SECTIONS_PGSHIFT) & SECTIONS_MASK; 552 } 553 554 static inline void set_page_zone(struct page *page, enum zone_type zone) 555 { 556 page->flags &= ~(ZONES_MASK << ZONES_PGSHIFT); 557 page->flags |= (zone & ZONES_MASK) << ZONES_PGSHIFT; 558 } 559 560 static inline void set_page_node(struct page *page, unsigned long node) 561 { 562 page->flags &= ~(NODES_MASK << NODES_PGSHIFT); 563 page->flags |= (node & NODES_MASK) << NODES_PGSHIFT; 564 } 565 566 static inline void set_page_section(struct page *page, unsigned long section) 567 { 568 page->flags &= ~(SECTIONS_MASK << SECTIONS_PGSHIFT); 569 page->flags |= (section & SECTIONS_MASK) << SECTIONS_PGSHIFT; 570 } 571 572 static inline void set_page_links(struct page *page, enum zone_type zone, 573 unsigned long node, unsigned long pfn) 574 { 575 set_page_zone(page, zone); 576 set_page_node(page, node); 577 set_page_section(page, pfn_to_section_nr(pfn)); 578 } 579 580 /* 581 * Some inline functions in vmstat.h depend on page_zone() 582 */ 583 #include <linux/vmstat.h> 584 585 static __always_inline void *lowmem_page_address(struct page *page) 586 { 587 return __va(page_to_pfn(page) << PAGE_SHIFT); 588 } 589 590 #if defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) 591 #define HASHED_PAGE_VIRTUAL 592 #endif 593 594 #if defined(WANT_PAGE_VIRTUAL) 595 #define page_address(page) ((page)->virtual) 596 #define set_page_address(page, address) \ 597 do { \ 598 (page)->virtual = (address); \ 599 } while(0) 600 #define page_address_init() do { } while(0) 601 #endif 602 603 #if defined(HASHED_PAGE_VIRTUAL) 604 void *page_address(struct page *page); 605 void set_page_address(struct page *page, void *virtual); 606 void page_address_init(void); 607 #endif 608 609 #if !defined(HASHED_PAGE_VIRTUAL) && !defined(WANT_PAGE_VIRTUAL) 610 #define page_address(page) lowmem_page_address(page) 611 #define set_page_address(page, address) do { } while(0) 612 #define page_address_init() do { } while(0) 613 #endif 614 615 /* 616 * On an anonymous page mapped into a user virtual memory area, 617 * page->mapping points to its anon_vma, not to a struct address_space; 618 * with the PAGE_MAPPING_ANON bit set to distinguish it. 619 * 620 * Please note that, confusingly, "page_mapping" refers to the inode 621 * address_space which maps the page from disk; whereas "page_mapped" 622 * refers to user virtual address space into which the page is mapped. 623 */ 624 #define PAGE_MAPPING_ANON 1 625 626 extern struct address_space swapper_space; 627 static inline struct address_space *page_mapping(struct page *page) 628 { 629 struct address_space *mapping = page->mapping; 630 631 VM_BUG_ON(PageSlab(page)); 632 if (unlikely(PageSwapCache(page))) 633 mapping = &swapper_space; 634 #ifdef CONFIG_SLUB 635 else if (unlikely(PageSlab(page))) 636 mapping = NULL; 637 #endif 638 else if (unlikely((unsigned long)mapping & PAGE_MAPPING_ANON)) 639 mapping = NULL; 640 return mapping; 641 } 642 643 static inline int PageAnon(struct page *page) 644 { 645 return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0; 646 } 647 648 /* 649 * Return the pagecache index of the passed page. Regular pagecache pages 650 * use ->index whereas swapcache pages use ->private 651 */ 652 static inline pgoff_t page_index(struct page *page) 653 { 654 if (unlikely(PageSwapCache(page))) 655 return page_private(page); 656 return page->index; 657 } 658 659 /* 660 * The atomic page->_mapcount, like _count, starts from -1: 661 * so that transitions both from it and to it can be tracked, 662 * using atomic_inc_and_test and atomic_add_negative(-1). 663 */ 664 static inline void reset_page_mapcount(struct page *page) 665 { 666 atomic_set(&(page)->_mapcount, -1); 667 } 668 669 static inline int page_mapcount(struct page *page) 670 { 671 return atomic_read(&(page)->_mapcount) + 1; 672 } 673 674 /* 675 * Return true if this page is mapped into pagetables. 676 */ 677 static inline int page_mapped(struct page *page) 678 { 679 return atomic_read(&(page)->_mapcount) >= 0; 680 } 681 682 /* 683 * Error return values for the *_nopage functions 684 */ 685 #define NOPAGE_SIGBUS (NULL) 686 #define NOPAGE_OOM ((struct page *) (-1)) 687 688 /* 689 * Error return values for the *_nopfn functions 690 */ 691 #define NOPFN_SIGBUS ((unsigned long) -1) 692 #define NOPFN_OOM ((unsigned long) -2) 693 #define NOPFN_REFAULT ((unsigned long) -3) 694 695 /* 696 * Different kinds of faults, as returned by handle_mm_fault(). 697 * Used to decide whether a process gets delivered SIGBUS or 698 * just gets major/minor fault counters bumped up. 699 */ 700 701 #define VM_FAULT_MINOR 0 /* For backwards compat. Remove me quickly. */ 702 703 #define VM_FAULT_OOM 0x0001 704 #define VM_FAULT_SIGBUS 0x0002 705 #define VM_FAULT_MAJOR 0x0004 706 #define VM_FAULT_WRITE 0x0008 /* Special case for get_user_pages */ 707 708 #define VM_FAULT_NOPAGE 0x0100 /* ->fault installed the pte, not return page */ 709 #define VM_FAULT_LOCKED 0x0200 /* ->fault locked the returned page */ 710 711 #define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS) 712 713 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) 714 715 extern void show_free_areas(void); 716 717 #ifdef CONFIG_SHMEM 718 int shmem_set_policy(struct vm_area_struct *vma, struct mempolicy *new); 719 struct mempolicy *shmem_get_policy(struct vm_area_struct *vma, 720 unsigned long addr); 721 int shmem_lock(struct file *file, int lock, struct user_struct *user); 722 #else 723 static inline int shmem_lock(struct file *file, int lock, 724 struct user_struct *user) 725 { 726 return 0; 727 } 728 729 static inline int shmem_set_policy(struct vm_area_struct *vma, 730 struct mempolicy *new) 731 { 732 return 0; 733 } 734 735 static inline struct mempolicy *shmem_get_policy(struct vm_area_struct *vma, 736 unsigned long addr) 737 { 738 return NULL; 739 } 740 #endif 741 struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags); 742 743 int shmem_zero_setup(struct vm_area_struct *); 744 745 #ifndef CONFIG_MMU 746 extern unsigned long shmem_get_unmapped_area(struct file *file, 747 unsigned long addr, 748 unsigned long len, 749 unsigned long pgoff, 750 unsigned long flags); 751 #endif 752 753 extern int can_do_mlock(void); 754 extern int user_shm_lock(size_t, struct user_struct *); 755 extern void user_shm_unlock(size_t, struct user_struct *); 756 757 /* 758 * Parameter block passed down to zap_pte_range in exceptional cases. 759 */ 760 struct zap_details { 761 struct vm_area_struct *nonlinear_vma; /* Check page->index if set */ 762 struct address_space *check_mapping; /* Check page->mapping if set */ 763 pgoff_t first_index; /* Lowest page->index to unmap */ 764 pgoff_t last_index; /* Highest page->index to unmap */ 765 spinlock_t *i_mmap_lock; /* For unmap_mapping_range: */ 766 unsigned long truncate_count; /* Compare vm_truncate_count */ 767 }; 768 769 struct page *vm_normal_page(struct vm_area_struct *, unsigned long, pte_t); 770 unsigned long zap_page_range(struct vm_area_struct *vma, unsigned long address, 771 unsigned long size, struct zap_details *); 772 unsigned long unmap_vmas(struct mmu_gather **tlb, 773 struct vm_area_struct *start_vma, unsigned long start_addr, 774 unsigned long end_addr, unsigned long *nr_accounted, 775 struct zap_details *); 776 void free_pgd_range(struct mmu_gather **tlb, unsigned long addr, 777 unsigned long end, unsigned long floor, unsigned long ceiling); 778 void free_pgtables(struct mmu_gather **tlb, struct vm_area_struct *start_vma, 779 unsigned long floor, unsigned long ceiling); 780 int copy_page_range(struct mm_struct *dst, struct mm_struct *src, 781 struct vm_area_struct *vma); 782 int zeromap_page_range(struct vm_area_struct *vma, unsigned long from, 783 unsigned long size, pgprot_t prot); 784 void unmap_mapping_range(struct address_space *mapping, 785 loff_t const holebegin, loff_t const holelen, int even_cows); 786 787 static inline void unmap_shared_mapping_range(struct address_space *mapping, 788 loff_t const holebegin, loff_t const holelen) 789 { 790 unmap_mapping_range(mapping, holebegin, holelen, 0); 791 } 792 793 extern int vmtruncate(struct inode * inode, loff_t offset); 794 extern int vmtruncate_range(struct inode * inode, loff_t offset, loff_t end); 795 796 #ifdef CONFIG_MMU 797 extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, 798 unsigned long address, int write_access); 799 #else 800 static inline int handle_mm_fault(struct mm_struct *mm, 801 struct vm_area_struct *vma, unsigned long address, 802 int write_access) 803 { 804 /* should never happen if there's no MMU */ 805 BUG(); 806 return VM_FAULT_SIGBUS; 807 } 808 #endif 809 810 extern int make_pages_present(unsigned long addr, unsigned long end); 811 extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write); 812 813 int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, 814 int len, int write, int force, struct page **pages, struct vm_area_struct **vmas); 815 void print_bad_pte(struct vm_area_struct *, pte_t, unsigned long); 816 817 extern int try_to_release_page(struct page * page, gfp_t gfp_mask); 818 extern void do_invalidatepage(struct page *page, unsigned long offset); 819 820 int __set_page_dirty_nobuffers(struct page *page); 821 int __set_page_dirty_no_writeback(struct page *page); 822 int redirty_page_for_writepage(struct writeback_control *wbc, 823 struct page *page); 824 int FASTCALL(set_page_dirty(struct page *page)); 825 int set_page_dirty_lock(struct page *page); 826 int clear_page_dirty_for_io(struct page *page); 827 828 extern unsigned long move_page_tables(struct vm_area_struct *vma, 829 unsigned long old_addr, struct vm_area_struct *new_vma, 830 unsigned long new_addr, unsigned long len); 831 extern unsigned long do_mremap(unsigned long addr, 832 unsigned long old_len, unsigned long new_len, 833 unsigned long flags, unsigned long new_addr); 834 extern int mprotect_fixup(struct vm_area_struct *vma, 835 struct vm_area_struct **pprev, unsigned long start, 836 unsigned long end, unsigned long newflags); 837 838 /* 839 * A callback you can register to apply pressure to ageable caches. 840 * 841 * 'shrink' is passed a count 'nr_to_scan' and a 'gfpmask'. It should 842 * look through the least-recently-used 'nr_to_scan' entries and 843 * attempt to free them up. It should return the number of objects 844 * which remain in the cache. If it returns -1, it means it cannot do 845 * any scanning at this time (eg. there is a risk of deadlock). 846 * 847 * The 'gfpmask' refers to the allocation we are currently trying to 848 * fulfil. 849 * 850 * Note that 'shrink' will be passed nr_to_scan == 0 when the VM is 851 * querying the cache size, so a fastpath for that case is appropriate. 852 */ 853 struct shrinker { 854 int (*shrink)(int nr_to_scan, gfp_t gfp_mask); 855 int seeks; /* seeks to recreate an obj */ 856 857 /* These are for internal use */ 858 struct list_head list; 859 long nr; /* objs pending delete */ 860 }; 861 #define DEFAULT_SEEKS 2 /* A good number if you don't know better. */ 862 extern void register_shrinker(struct shrinker *); 863 extern void unregister_shrinker(struct shrinker *); 864 865 int vma_wants_writenotify(struct vm_area_struct *vma); 866 867 extern pte_t *FASTCALL(get_locked_pte(struct mm_struct *mm, unsigned long addr, spinlock_t **ptl)); 868 869 #ifdef __PAGETABLE_PUD_FOLDED 870 static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, 871 unsigned long address) 872 { 873 return 0; 874 } 875 #else 876 int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address); 877 #endif 878 879 #ifdef __PAGETABLE_PMD_FOLDED 880 static inline int __pmd_alloc(struct mm_struct *mm, pud_t *pud, 881 unsigned long address) 882 { 883 return 0; 884 } 885 #else 886 int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address); 887 #endif 888 889 int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address); 890 int __pte_alloc_kernel(pmd_t *pmd, unsigned long address); 891 892 /* 893 * The following ifdef needed to get the 4level-fixup.h header to work. 894 * Remove it when 4level-fixup.h has been removed. 895 */ 896 #if defined(CONFIG_MMU) && !defined(__ARCH_HAS_4LEVEL_HACK) 897 static inline pud_t *pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address) 898 { 899 return (unlikely(pgd_none(*pgd)) && __pud_alloc(mm, pgd, address))? 900 NULL: pud_offset(pgd, address); 901 } 902 903 static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) 904 { 905 return (unlikely(pud_none(*pud)) && __pmd_alloc(mm, pud, address))? 906 NULL: pmd_offset(pud, address); 907 } 908 #endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */ 909 910 #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS 911 /* 912 * We tuck a spinlock to guard each pagetable page into its struct page, 913 * at page->private, with BUILD_BUG_ON to make sure that this will not 914 * overflow into the next struct page (as it might with DEBUG_SPINLOCK). 915 * When freeing, reset page->mapping so free_pages_check won't complain. 916 */ 917 #define __pte_lockptr(page) &((page)->ptl) 918 #define pte_lock_init(_page) do { \ 919 spin_lock_init(__pte_lockptr(_page)); \ 920 } while (0) 921 #define pte_lock_deinit(page) ((page)->mapping = NULL) 922 #define pte_lockptr(mm, pmd) ({(void)(mm); __pte_lockptr(pmd_page(*(pmd)));}) 923 #else 924 /* 925 * We use mm->page_table_lock to guard all pagetable pages of the mm. 926 */ 927 #define pte_lock_init(page) do {} while (0) 928 #define pte_lock_deinit(page) do {} while (0) 929 #define pte_lockptr(mm, pmd) ({(void)(pmd); &(mm)->page_table_lock;}) 930 #endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */ 931 932 #define pte_offset_map_lock(mm, pmd, address, ptlp) \ 933 ({ \ 934 spinlock_t *__ptl = pte_lockptr(mm, pmd); \ 935 pte_t *__pte = pte_offset_map(pmd, address); \ 936 *(ptlp) = __ptl; \ 937 spin_lock(__ptl); \ 938 __pte; \ 939 }) 940 941 #define pte_unmap_unlock(pte, ptl) do { \ 942 spin_unlock(ptl); \ 943 pte_unmap(pte); \ 944 } while (0) 945 946 #define pte_alloc_map(mm, pmd, address) \ 947 ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \ 948 NULL: pte_offset_map(pmd, address)) 949 950 #define pte_alloc_map_lock(mm, pmd, address, ptlp) \ 951 ((unlikely(!pmd_present(*(pmd))) && __pte_alloc(mm, pmd, address))? \ 952 NULL: pte_offset_map_lock(mm, pmd, address, ptlp)) 953 954 #define pte_alloc_kernel(pmd, address) \ 955 ((unlikely(!pmd_present(*(pmd))) && __pte_alloc_kernel(pmd, address))? \ 956 NULL: pte_offset_kernel(pmd, address)) 957 958 extern void free_area_init(unsigned long * zones_size); 959 extern void free_area_init_node(int nid, pg_data_t *pgdat, 960 unsigned long * zones_size, unsigned long zone_start_pfn, 961 unsigned long *zholes_size); 962 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP 963 /* 964 * With CONFIG_ARCH_POPULATES_NODE_MAP set, an architecture may initialise its 965 * zones, allocate the backing mem_map and account for memory holes in a more 966 * architecture independent manner. This is a substitute for creating the 967 * zone_sizes[] and zholes_size[] arrays and passing them to 968 * free_area_init_node() 969 * 970 * An architecture is expected to register range of page frames backed by 971 * physical memory with add_active_range() before calling 972 * free_area_init_nodes() passing in the PFN each zone ends at. At a basic 973 * usage, an architecture is expected to do something like 974 * 975 * unsigned long max_zone_pfns[MAX_NR_ZONES] = {max_dma, max_normal_pfn, 976 * max_highmem_pfn}; 977 * for_each_valid_physical_page_range() 978 * add_active_range(node_id, start_pfn, end_pfn) 979 * free_area_init_nodes(max_zone_pfns); 980 * 981 * If the architecture guarantees that there are no holes in the ranges 982 * registered with add_active_range(), free_bootmem_active_regions() 983 * will call free_bootmem_node() for each registered physical page range. 984 * Similarly sparse_memory_present_with_active_regions() calls 985 * memory_present() for each range when SPARSEMEM is enabled. 986 * 987 * See mm/page_alloc.c for more information on each function exposed by 988 * CONFIG_ARCH_POPULATES_NODE_MAP 989 */ 990 extern void free_area_init_nodes(unsigned long *max_zone_pfn); 991 extern void add_active_range(unsigned int nid, unsigned long start_pfn, 992 unsigned long end_pfn); 993 extern void shrink_active_range(unsigned int nid, unsigned long old_end_pfn, 994 unsigned long new_end_pfn); 995 extern void push_node_boundaries(unsigned int nid, unsigned long start_pfn, 996 unsigned long end_pfn); 997 extern void remove_all_active_ranges(void); 998 extern unsigned long absent_pages_in_range(unsigned long start_pfn, 999 unsigned long end_pfn); 1000 extern void get_pfn_range_for_nid(unsigned int nid, 1001 unsigned long *start_pfn, unsigned long *end_pfn); 1002 extern unsigned long find_min_pfn_with_active_regions(void); 1003 extern unsigned long find_max_pfn_with_active_regions(void); 1004 extern void free_bootmem_with_active_regions(int nid, 1005 unsigned long max_low_pfn); 1006 extern void sparse_memory_present_with_active_regions(int nid); 1007 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID 1008 extern int early_pfn_to_nid(unsigned long pfn); 1009 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */ 1010 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ 1011 extern void set_dma_reserve(unsigned long new_dma_reserve); 1012 extern void memmap_init_zone(unsigned long, int, unsigned long, 1013 unsigned long, enum memmap_context); 1014 extern void setup_per_zone_pages_min(void); 1015 extern void mem_init(void); 1016 extern void show_mem(void); 1017 extern void si_meminfo(struct sysinfo * val); 1018 extern void si_meminfo_node(struct sysinfo *val, int nid); 1019 1020 #ifdef CONFIG_NUMA 1021 extern void setup_per_cpu_pageset(void); 1022 #else 1023 static inline void setup_per_cpu_pageset(void) {} 1024 #endif 1025 1026 /* prio_tree.c */ 1027 void vma_prio_tree_add(struct vm_area_struct *, struct vm_area_struct *old); 1028 void vma_prio_tree_insert(struct vm_area_struct *, struct prio_tree_root *); 1029 void vma_prio_tree_remove(struct vm_area_struct *, struct prio_tree_root *); 1030 struct vm_area_struct *vma_prio_tree_next(struct vm_area_struct *vma, 1031 struct prio_tree_iter *iter); 1032 1033 #define vma_prio_tree_foreach(vma, iter, root, begin, end) \ 1034 for (prio_tree_iter_init(iter, root, begin, end), vma = NULL; \ 1035 (vma = vma_prio_tree_next(vma, iter)); ) 1036 1037 static inline void vma_nonlinear_insert(struct vm_area_struct *vma, 1038 struct list_head *list) 1039 { 1040 vma->shared.vm_set.parent = NULL; 1041 list_add_tail(&vma->shared.vm_set.list, list); 1042 } 1043 1044 /* mmap.c */ 1045 extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin); 1046 extern void vma_adjust(struct vm_area_struct *vma, unsigned long start, 1047 unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert); 1048 extern struct vm_area_struct *vma_merge(struct mm_struct *, 1049 struct vm_area_struct *prev, unsigned long addr, unsigned long end, 1050 unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t, 1051 struct mempolicy *); 1052 extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *); 1053 extern int split_vma(struct mm_struct *, 1054 struct vm_area_struct *, unsigned long addr, int new_below); 1055 extern int insert_vm_struct(struct mm_struct *, struct vm_area_struct *); 1056 extern void __vma_link_rb(struct mm_struct *, struct vm_area_struct *, 1057 struct rb_node **, struct rb_node *); 1058 extern void unlink_file_vma(struct vm_area_struct *); 1059 extern struct vm_area_struct *copy_vma(struct vm_area_struct **, 1060 unsigned long addr, unsigned long len, pgoff_t pgoff); 1061 extern void exit_mmap(struct mm_struct *); 1062 extern int may_expand_vm(struct mm_struct *mm, unsigned long npages); 1063 extern int install_special_mapping(struct mm_struct *mm, 1064 unsigned long addr, unsigned long len, 1065 unsigned long flags, struct page **pages); 1066 1067 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); 1068 1069 extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, 1070 unsigned long len, unsigned long prot, 1071 unsigned long flag, unsigned long pgoff); 1072 extern unsigned long mmap_region(struct file *file, unsigned long addr, 1073 unsigned long len, unsigned long flags, 1074 unsigned int vm_flags, unsigned long pgoff, 1075 int accountable); 1076 1077 static inline unsigned long do_mmap(struct file *file, unsigned long addr, 1078 unsigned long len, unsigned long prot, 1079 unsigned long flag, unsigned long offset) 1080 { 1081 unsigned long ret = -EINVAL; 1082 if ((offset + PAGE_ALIGN(len)) < offset) 1083 goto out; 1084 if (!(offset & ~PAGE_MASK)) 1085 ret = do_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT); 1086 out: 1087 return ret; 1088 } 1089 1090 extern int do_munmap(struct mm_struct *, unsigned long, size_t); 1091 1092 extern unsigned long do_brk(unsigned long, unsigned long); 1093 1094 /* filemap.c */ 1095 extern unsigned long page_unuse(struct page *); 1096 extern void truncate_inode_pages(struct address_space *, loff_t); 1097 extern void truncate_inode_pages_range(struct address_space *, 1098 loff_t lstart, loff_t lend); 1099 1100 /* generic vm_area_ops exported for stackable file systems */ 1101 extern int filemap_fault(struct vm_area_struct *, struct vm_fault *); 1102 1103 /* mm/page-writeback.c */ 1104 int write_one_page(struct page *page, int wait); 1105 1106 /* readahead.c */ 1107 #define VM_MAX_READAHEAD 128 /* kbytes */ 1108 #define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */ 1109 #define VM_MAX_CACHE_HIT 256 /* max pages in a row in cache before 1110 * turning readahead off */ 1111 1112 int do_page_cache_readahead(struct address_space *mapping, struct file *filp, 1113 pgoff_t offset, unsigned long nr_to_read); 1114 int force_page_cache_readahead(struct address_space *mapping, struct file *filp, 1115 pgoff_t offset, unsigned long nr_to_read); 1116 1117 void page_cache_sync_readahead(struct address_space *mapping, 1118 struct file_ra_state *ra, 1119 struct file *filp, 1120 pgoff_t offset, 1121 unsigned long size); 1122 1123 void page_cache_async_readahead(struct address_space *mapping, 1124 struct file_ra_state *ra, 1125 struct file *filp, 1126 struct page *pg, 1127 pgoff_t offset, 1128 unsigned long size); 1129 1130 unsigned long max_sane_readahead(unsigned long nr); 1131 1132 /* Do stack extension */ 1133 extern int expand_stack(struct vm_area_struct *vma, unsigned long address); 1134 #ifdef CONFIG_IA64 1135 extern int expand_upwards(struct vm_area_struct *vma, unsigned long address); 1136 #endif 1137 extern int expand_stack_downwards(struct vm_area_struct *vma, 1138 unsigned long address); 1139 1140 /* Look up the first VMA which satisfies addr < vm_end, NULL if none. */ 1141 extern struct vm_area_struct * find_vma(struct mm_struct * mm, unsigned long addr); 1142 extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr, 1143 struct vm_area_struct **pprev); 1144 1145 /* Look up the first VMA which intersects the interval start_addr..end_addr-1, 1146 NULL if none. Assume start_addr < end_addr. */ 1147 static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * mm, unsigned long start_addr, unsigned long end_addr) 1148 { 1149 struct vm_area_struct * vma = find_vma(mm,start_addr); 1150 1151 if (vma && end_addr <= vma->vm_start) 1152 vma = NULL; 1153 return vma; 1154 } 1155 1156 static inline unsigned long vma_pages(struct vm_area_struct *vma) 1157 { 1158 return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; 1159 } 1160 1161 pgprot_t vm_get_page_prot(unsigned long vm_flags); 1162 struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr); 1163 struct page *vmalloc_to_page(void *addr); 1164 unsigned long vmalloc_to_pfn(void *addr); 1165 int remap_pfn_range(struct vm_area_struct *, unsigned long addr, 1166 unsigned long pfn, unsigned long size, pgprot_t); 1167 int vm_insert_page(struct vm_area_struct *, unsigned long addr, struct page *); 1168 int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr, 1169 unsigned long pfn); 1170 1171 struct page *follow_page(struct vm_area_struct *, unsigned long address, 1172 unsigned int foll_flags); 1173 #define FOLL_WRITE 0x01 /* check pte is writable */ 1174 #define FOLL_TOUCH 0x02 /* mark page accessed */ 1175 #define FOLL_GET 0x04 /* do get_page on page */ 1176 #define FOLL_ANON 0x08 /* give ZERO_PAGE if no pgtable */ 1177 1178 typedef int (*pte_fn_t)(pte_t *pte, struct page *pmd_page, unsigned long addr, 1179 void *data); 1180 extern int apply_to_page_range(struct mm_struct *mm, unsigned long address, 1181 unsigned long size, pte_fn_t fn, void *data); 1182 1183 #ifdef CONFIG_PROC_FS 1184 void vm_stat_account(struct mm_struct *, unsigned long, struct file *, long); 1185 #else 1186 static inline void vm_stat_account(struct mm_struct *mm, 1187 unsigned long flags, struct file *file, long pages) 1188 { 1189 } 1190 #endif /* CONFIG_PROC_FS */ 1191 1192 #ifndef CONFIG_DEBUG_PAGEALLOC 1193 static inline void 1194 kernel_map_pages(struct page *page, int numpages, int enable) {} 1195 #endif 1196 1197 extern struct vm_area_struct *get_gate_vma(struct task_struct *tsk); 1198 #ifdef __HAVE_ARCH_GATE_AREA 1199 int in_gate_area_no_task(unsigned long addr); 1200 int in_gate_area(struct task_struct *task, unsigned long addr); 1201 #else 1202 int in_gate_area_no_task(unsigned long addr); 1203 #define in_gate_area(task, addr) ({(void)task; in_gate_area_no_task(addr);}) 1204 #endif /* __HAVE_ARCH_GATE_AREA */ 1205 1206 int drop_caches_sysctl_handler(struct ctl_table *, int, struct file *, 1207 void __user *, size_t *, loff_t *); 1208 unsigned long shrink_slab(unsigned long scanned, gfp_t gfp_mask, 1209 unsigned long lru_pages); 1210 void drop_pagecache(void); 1211 void drop_slab(void); 1212 1213 #ifndef CONFIG_MMU 1214 #define randomize_va_space 0 1215 #else 1216 extern int randomize_va_space; 1217 #endif 1218 1219 const char * arch_vma_name(struct vm_area_struct *vma); 1220 1221 #endif /* __KERNEL__ */ 1222 #endif /* _LINUX_MM_H */ 1223